The aims of this study were to identify, assess, and summarise available evidence about the effectiveness of static air mattress overlays to prevent pressure ulcers. The primary outcome was the incidence of pressure ulcers. Secondary outcomes included costs and patient comfort. This study was a systematic review. Six electronic databases were consulted: Cochrane Library, EMBASE, PubMed (Medline), CINAHL (EBSCOhost interface), Science direct, and Web of Science. In addition, a hand search through reviews, conference proceedings, and the reference lists of the included studies was performed to identify additional studies. Potential studies were reviewed and assessed by 2 independent authors based on the title and abstract. Decisions regarding inclusion or exclusion of the studies were based on a consensus between the authors. Studies were included if the following criteria were met: reporting an original study; the outcome was the incidence of pressure ulcer categories I to IV when using a static air mattress overlay and/or in comparison with other pressure-redistribution device(s); and studies published in English, French, and Dutch. No limitation was set on study setting, design, and date of publication. The methodological quality assessment was evaluated using the Critical Appraisal Skills Program Tool. Results were reported in a descriptive way to reflect the exploratory nature of the review. The searches included 13 studies: randomised controlled trials (n = 11) and cohort studies (n = 2). The mean pressure ulcer incidence figures found in the different settings were, respectively, 7.8% pressure ulcers of categories II to IV in nursing homes, 9.06% pressure ulcers of categories I to IV in intensive care settings, and 12% pressure ulcers of categories I to IV in orthopaedic wards. Seven comparative studies reported a lower incidence in the groups of patients on a static air mattress overlay. Three studies reported a statistical (P < .1) lower incidence compared with a standard hospital mattress (10 cm thick, density 35 kg/m3), a foam mattress (15 cm thick), and a viscoelastic foam mattress (15 cm thick). No significant difference in incidence, purchase costs, and patient comfort was found compared with dynamic air mattresses. This review focused on the effectiveness of static air mattress overlays to prevent pressure ulcers. There are indications that these mattress overlays are more effective in preventing pressure ulcers compared with the use of a standard mattress or a pressure-reducing foam mattress in nursing homes and intensive care settings. However, interpretation of the evidence should be performed with caution due to the wide variety of methodological and/or reporting quality levels of the included studies.
Δευτέρα 12 Μαρτίου 2018
Functional characterisation of bioactive peptide derived from terrestrial snail Cryptozona bistrialis and its wound-healing property in normal and diabetic-induced Wistar albino rats
Abstract
A peptide might be an exciting biomaterial or template for the development of novel wound-healing agents. In this report, it was isolated from the terrestrial snail Cryptozona bistrialis by enzymatic digestion and was evaluated for its in vitro wound-healing activity in NIH/3T3 mouse fibroblasts cell line and in vivo wound-healing activity in normal and diabetic-induced Wistar albino rats. The C. bistrialis protein was digested by the papain enzyme, and 21.79 kDa peptide (Cb-peptide) was purified by reversed-phase high-performance liquid chromatography and identified by MALDI (matrix-assisted laser desorption/ionization)-TOF analysis. The isolated Cb-peptide was characterised by various analytical methods. The peptide demonstrated a capacity to prevent the development of pathogenic bacterial and fungal cultures and proved that it promotes significant wound-healing activity in the wound scratch assay method by rapid cell migration and closure of wound. Isolated Cb-peptide was lyophilised and formulated to ointment and analysed for in vivo wound-healing activity in normal and diabetic (alloxan monohydrate)-induced Wistar albino rats. Cb-peptide ointment-treated groups showed a greater degree of wound healing and early and complete period of epithelialisation in normal and diabetic-induced Wistar albino rats. Cb-peptide ointment-treated groups showed significant excision and incision wound-healing activity. A conclusion was reached that the peptide isolated from C. bistrialis showed greater wound-healing activity compared with vehicle control and standard control.
Growth hormone-releasing peptide 6 prevents cutaneous hypertrophic scarring: early mechanistic data from a proteome study
Hypertrophic scars (HTS) and keloids are forms of aberrant cutaneous healing with excessive extracellular matrix (ECM) deposition. Current therapies still fall short and cause undesired effects. We aimed to thoroughly evaluate the ability of growth hormone releasing peptide 6 (GHRP6) to both prevent and reverse cutaneous fibrosis and to acquire the earliest proteome data supporting GHRP6's acute impact on aesthetic wound healing. Two independent sets of experiments addressing prevention and reversion effects were conducted on the classic HTS model in rabbits. In the prevention approach, the wounds were assigned to topically receive GHRP6, triamcinolone acetonide (TA), or vehicle (1% sodium carboxy methylcellulose [CMC]) from day 1 to day 30 post-wounding. The reversion scheme was based on the infiltration of either GHRP6 or sterile saline in mature HTS for 4 consecutive weeks. The incidence and appearance of HTS were systematically monitored. The sub-epidermal fibrotic core area of HTS was ultrasonographically determined, and the scar elevation index was calculated on haematoxylin/eosin-stained, microscopic digitised images. Tissue samples were collected for proteomics after 1 hour of HTS induction and treatment with either GHRP6 or vehicle. GHRP6 prevented the onset of HTS without the untoward reactions induced by the first-line treatment triamcinolone acetonide (TA); however, it failed to significantly reverse mature HTS. The preliminary proteomic study suggests that the anti-fibrotic preventing effect exerted by GHRP6 depends on different pathways involved in lipid metabolism, cytoskeleton arrangements, epidermal cells' differentiation, and ECM dynamics. These results enlighten the potential success of GHRP6 as one of the incoming alternatives for HTS prevention.
Prevalence of skin tears in the extremities in inpatients at a hospital in Denmark
Abstract
The aims of the study were to determine the prevalence of skin tears in the extremities and to explore factors associated with development of skin tears in inpatients at a Danish hospital. The study was designed as a point prevalence survey and included 202 patients in the age range 19–99 (mean: 70·7, SD: 16·5). The patients were assessed for presence of skin tears, numbers, locations and previous skin tears. Data were collected using a data collection sheet developed for a previous study. The survey team consisted of four specialist nurses. Data were collected over a period of 24 hours spread over 3 days. Of the 202 patients, 23 had skin tears, yielding a prevalence of 11·4%. In total, 40 skin tears were observed. Multiple logistic regression analysis showed that previous skin tears (odds ratio (OR): 9·3, 95% confidence interval (CI): 2·6–33·4, P < 0·001), ecchymosis (OR: 5·6, CI: 1·4-23·2, P < 0·017) and risk of falling (OR: 3·8, CI: 1·2-12·0, P < 0·021) were significantly associated with development of skin tears. The prevalence of skin tears in this study (11·4%) matches other international observations. The following risk factors were recognised: previous skin tear, ecchymosis and risk of falling. These factors could be used to identify patients requiring prevention of skin tears.
Systematic review of the use of Statistical Process Control methods to measure the success of pressure ulcer prevention
Successful prevention of pressure ulcers is the end product of a complex series of care processes including, but not limited to, the assessment of vulnerability to pressure damage; skin assessment and care; nutritional support; repositioning; and the use of beds, mattresses, and cushions to manage mechanical loads on the skin and soft tissues. The purpose of this review was to examine where and how Statistical Process Control (SPC) measures have been used to assess the success of quality improvement initiatives intended to improve pressure ulcer prevention. A search of 7 electronic bibliographic databases was performed on May 17th, 2017, for studies that met the inclusion criteria. SPC methods have been reported in 9 publications since 2010 to interpret changes in the incidence of pressure ulcers over time. While these methods offer rapid interpretation of changes in incidence than is gained from a comparison of 2 arbitrarily selected time points pre- and post-implementation of change, more work is required to ensure that the clinical and scientific communities adopt the most appropriate SPC methods.
What is the effect of exercise on wound healing in patients with venous leg ulcers? A systematic review
Standard best practice for the treatment of venous leg ulcers (VLUs) is compression bandaging of the lower leg to reduce hydrostatic pressure. There is considerable variation in reported healing rates when using this gold-standard approach; therefore, a systematic and robust evaluation of other interventions is required. Exercise interventions, in addition to standard compression therapy, could improve wound-healing time and prevent their recurrence. We have conducted a systematic review to examine the effects of exercise on wound characteristics, including time to heal, size and recurrence, pain, quality of life, adverse events, and economic outcomes. This review was registered with PROSPERO 2016:CRD42016046407. A systematic search of Ovid Medline, Ovid EMBASE, Ovid CINAHL, The Cochrane Library, PsycINFO, Web of Science, and PEDro was conducted on January 30, 2017, for randomised control trials to examine the effects of exercise on time to heal, size and recurrence, pain, quality of life, adverse events, and economic outcomes. Six studies met the inclusion criteria, but all had design flaws leading to biases, most commonly performance and selective reporting bias. Three studies compared a progressive resistance exercise programme (PREG) plus compression with compression alone for a period of 12 weeks. Low-quality evidence indicates the following: possibly no difference in the proportion of ulcers healed (risk ratio [RR] 1.14, 95% CI 0.71 to 1.84, I2 36%; 3 trials, 116 participants); probably no difference in quality of life (mean difference [MD] 3 points better on 100 point scale with exercise, 95% CI −1.89 to 7.89, 1 trial, 59 participants); possible increase in the risk of adverse events with exercise (OR 1.32, 95% CI 0.95 to 1.85, 1 RCT, 40 participants); and no difference in ankle range of motion and calf muscle pump. Evidence was downgraded due to susceptibility to bias and imprecision. Recurrence, pain, and economic outcomes were not measured in these trials, and time to healing was measured but not fully reported in 1 trial. We are uncertain of the effects of other interventions (community-based exercise and behaviour modification, ten thousand steps, supervised vs unsupervised exercise) due to the availability of low- or very low-quality evidence only from single trials. The review highlights the need for further research, with larger sample sizes, to properly address the significance of the effect of exercise on VLU wound characteristics.
Slow to heel: a literature review on the management of diabetic calcaneal ulceration
Abstract
The diabetic heel ulcer (DHU) represents a reconstructive challenge to clinicians and the multidisciplinary team alike. It is traditionally viewed as a condition that is inherently difficult to treat due to the intrinsic anatomical vulnerabilities of the heel. In addition to this, several factors are associated with poorer end outcomes – namely, that of major amputation. These include peripheral vascular disease, infection/osteomyelitis and the size of the ulcer itself. In light of the significant morbidity, economic burden and mortality seen in this cohort of patients, this review aims to explore current treatment modalities that have been undertaken. Literature in this field has mostly been confined to a handful of small case studies, some of which reflect novel, multimodal approaches, and promising results. Management with osteotomy, flap reconstruction and acellular dermal matrices, amongst other options, is covered within this review.
The ‘Two Bridges Technique’ for sternal wound closure. The use of vacuum-assisted closure for the treatment of deep sternal wound defects: a centre-specific technique
Abstract
The objective is to describe the 'Two Bridges Technique' (TBT), which has proven to be successful and has been the standard technique at our centre for vacuum-assisted closure (VAC) of post-sternotomy mediastinitis. An extensive literature search was performed in four databases to identify all published articles concerning VAC for post-sternotomy mediastinitis. Several VAC methods have been used; however, no article has described our specific technique. TBT consists of a two-bridges construction using two types of foam with different pore sizes, which ensures an equally divided negative pressure over the wound bed and stabilisation of the chest. This guarantees a continuous treatment of the sternal defect and prevents foam displacement. It maintains an airtight seal that prevents skin maceration and provides enough protection to avoid right ventricular rupture. The main advantage of TBT is the prevention of shifting or tilting of the foam during chest movements such as breathing or couching. Along with targeted antibiotic treatment, this alternative VAC technique can be an asset in the sometimes cumbersome treatment of post-sternotomy mediastinitis.
Physical Activity, Body Mass Index, and Clustered Metabolic Risk in U.S. Adolescents: 2007–2012 Nhanes
Metabolic Syndrome and Related Disorders, Volume 16, Issue 2, Page 97-103, March 2018.
Relationship Between Paraoxonase-1 and Butyrylcholinesterase Activities and Nutritional Status in Mexican Children
Metabolic Syndrome and Related Disorders, Volume 16, Issue 2, Page 90-96, March 2018.
Vaspin and Omentin-1 in Obese Children with Metabolic Syndrome: Two New Kids on the Block?
Metabolic Syndrome and Related Disorders, Volume 16, Issue 2, Page 73-75, March 2018.
Dietary Fiber, C-Reactive Protein, and Leisure-Time Physical Activity Among U.S. Adults
Metabolic Syndrome and Related Disorders, Volume 16, Issue 2, Page 104-109, March 2018.
Risk and Age of Cardiovascular Event in Women with Metabolic Syndrome: Menopause Age in Focus
Metabolic Syndrome and Related Disorders, Ahead of Print.
Association Between Carotid Intima Media Thickness, Age, and Cardiovascular Risk Factors in Children and Adolescents
Metabolic Syndrome and Related Disorders, Ahead of Print.
Persistence of TBT and copper in excess on leisure boat hulls around the Baltic Sea
Abstract
A handheld XRF-analyzer specially calibrated for measurements of metals on plastic boat hulls has been used on leisure boats in Denmark (DK), Finland (FI), and Germany (DE). The results on tin and copper are presented as μg metal/cm2. Tin is a proxy for the occurrence of organotin compounds on the boat. Two or three sites were visited in each country and between 25 and 90 boats were measured at each site. Every boat was measured at six to eight places, and the results are presented both as mean and median values. Linear regression of mean to median values of the 377 data pairs shows high relationship with R2 = 0.9566 for tin and R2 of 0.9724 for copper and thus both ways of calculation may be used. However, for regulative use, it is suggested that all individual measurements on each boat should be presented and used for decisions of removal or sealing of boat hulls. The results are compared with published data from different parts of Sweden, i.e., boats in fresh water, brackish water, and salt water. The results show that tin with mean values > 50 μg Sn/cm2 is still found on 42, 24, and 23% of the boats in DK, FI, and DE, respectively. The corresponding percentages based on median values are 38, 22, and 18% for DK, FI, and DE, respectively. The variation among boats is high with a maximum mean value of 2000 μg Sn/cm2. As comparison, one layer of an old TBT antifouling paint Hempels Hard racing superior, corresponds to 300 μg Sn/cm2. The percentage of boats with tin > 400 μg Sn/cm2 content based on mean values was 10% in DK, 5% in FI, and 1% in DE. The corresponding median values were 9, 6, and 1% for DK, FI, and DE. Copper, > 100 μg Cu/cm2, was detected on all measured boats in DK and in DE and on all but 3% of the FI boats. One layer of Hempels MilleXtra corresponds to ̴ 4000 μg Cu/cm2. The recommendation on the can is to apply two layers. The proportion of boats with higher mean copper values than 8000 μg Cu/cm2 was 51, 56, and 61 for boats in DK, FI, and DE, respectively. The proportion based on median values > 8000 μg Cu/cm2 was 50, 54, and 61% for DK, FI, and DE. The conclusion is that many leisure boats around the Baltic Sea still display or possess antifouling paints containing organotin compounds and that more than half of the boats have more copper than needed for one boat season according to the paint producers. Much of these known toxic compounds will probably be released into the environment and harm the biota. The calibrated XRF-method, intended for area measurements on boat hulls, is an easy and cheap way to detect boats with organotin compounds and high copper content. We recommend environmental authorities to use this method for identification of such boats and to use the results for requesting measures to minimize further leakage to the environment.
Potential harmful elements in coal dust and human health risk assessment near the mining areas in Cherat, Pakistan
Abstract
This study was aimed to investigate the potential harmful element (PHE) concentrations in coal dust and evaluate the human risk assessment and health effects near coal mining areas. For this purpose, dust samples were collected near various coal mines in Cherat, Pakistan, and analyzed for the PHE concentrations. Determined PHE concentrations were evaluated for the health risk assessment. Results revealed that ingestion was the major pathway as compared to others for PHE exposure. Individual chronic daily intake (CDI) of PHEs was higher than their respective permissible exposure limits set for oral exposure routes by the Agency for Toxic Substances and Disease Registry (ATSDR). Chronic risk or health index (HI) values were observed < 1 for all PHEs and in the order of Pb > Cr > Cd > Ni > Cu > Co > Zn. Higher HI values of Pb, Cr, and Cd could attribute to various chronic health problems as observed during the medical examination survey of this study. Cancer risk (CR) values for this study were observed within the US Environmental Protection Agency (EPA) limits. However, if current practices continued, the PHEs will cross these limits in a near future. Therefore, this study strongly recommends the provision of safety measures, rules, and regulation to avoid health hazards in the future.
Effect of dietary phytogenics (herbal mixture) supplementation on growth performance, nutrient utilization, antioxidative properties, and immune response in broilers
Abstract
This experiment was conducted to study that effect of a phytogenics (herbal mixture) supplementation as alternative to antibiotics on the growth performance and immune response in broilers. Three thousand broiler male chicks at 1 day of age were housed in floor pens and divided into five experimental groups with five replicates of 120 birds each. The first group was fed the basal diet without any additive in feed or water; the second group was fed the basal diet, and the drinking water was supplemented with mixture of antibiotics (Doxycycline 1 g/5 L + Colistine sulfate 1 g/5 L) for the first 10 days of life. The other three treatments of chickens were fed the control diet supplemented with herbal mixture at a level of 0.5, 1.0, and 1.5 kg/ton, respectively. Dietary herb mixture supplementation improved growth performance significantly in comparison with control group. In addition, herb mixture supplementation reduced plasma total cholesterol and triglycerides concentrations, whereas, high density lipoprotein HDL-cholesterol and glutathione peroxidase (GPX) were increased significantly. Furthermore, herb mixture supplementation increased plasma levels of total protein and antibodies titers for Newcastle disease virus before and after the infection. It could be concluded that dietary herb mixture supplementation had positive effects on growth performance, antioxidative properties, and humoral immunity in broiler chickens.
Comparison of nickel adsorption on biochars produced from mixed softwood and Miscanthus straw
Abstract
In order to understand the influence of feedstock type on biochar adsorption of heavy metals, the adsorption characteristics of nickel (Ni2+), copper (Cu2+) and lead (Pb2+) onto biochars derived from mixed softwood and Miscanthus straw were compared. The biochars were produced from mixed softwood pellets (SWP) and Miscanthus straw pellets (MSP), at both 550 and 700 °C for each material, using a standardised production procedure recommended by the UK Biochar Research Centre. Kinetics analyses show that the adsorption of Ni2+ to all four biochars reached equilibrium within 5 min. The degree of Ni2+ removal for all four biochars remained nearly constant within initial pH values of 3–8, because the equilibrium pH values within this range were similar due to the buffering effect of the biochars. A sharp increase of Ni2+ removal percentage for all biochars at initial solution pH 8–10 was observed as the equilibrium pH also increased. MSP derived biochars generally had higher maximum adsorption capacities (Qmax) for the three tested metals as compared with those from SWP, which was likely due to their higher degree of carbonisation during production. This study shows that feedstock type is a primary factor affecting the adsorption capacities of the tested biochars for heavy metals.
Effect of composition and microstructure of humic acid on 3,3′,4,4′-tetrachlorobiphenyl sorption
Abstract
The fate and transport of polychlorinated biphenyls (PCBs), a class of persistent organic compounds, in soils was markedly affected by their sorption/desorption on soil organic matters (SOM) due to high hydrophobicity of PCBs. Humic acid (HA), an important fraction of SOM, has no steady composition and microstructure from different origins, resulting in their diverse sorption capacity. Therefore, the effect of composition and microstructure of HA on sorption of 3,3′,4,4′-tetrachlorobiphenyl (PCB77) was investigated in this study. The primary sorption mechanism of PCB77 on HAs was also demonstrated by using Fourier transform infrared (FTIR) and solid-state carbon-13 nuclear magnetic resonance (13C-NMR) spectroscopy analysis. Elemental content analysis of three HAs showed that the content of unsaturated C (the total of aromatic, carboxylic, and carbonyl carbon) followed an order of YHA>SHA>AHA. Furthermore, YHA and SHA had remarkably rough and complicated particle surfaces but AHA had relatively smooth surface and the well-proportioned and interspersed particle sizes. The results of the sorption experiment showed that the sorption capacity of PCB77 on HAs followed a similar order of YHA>SHA>AHA, indicating the content of unsaturated C of HAs controlled the sorption of PCB77 on HAs. Sorption of PCB77 on either AHA or SHA did not change with increasing ionic strength of background solution, implying that there was no H-bond or electrostatic interaction between PCB77 and HAs. The result of FTIR and 13C-NMR spectra showed the primarily possible mechanism was π-π conjugative interaction and hydrophobic binding between PCB77 and HAs.
The use of probiotics as eco-friendly alternatives for antibiotics in poultry nutrition
Abstract
Antibiotics as growth promoters in poultry have been used for long time for improving feed efficiency and performance. Due to their various side-effects such as antibiotic resistance, destruction of beneficial bacteria in the gut, and dysbiosis, it is required to think about some alternatives. Probiotics are one of the options in this regard for improving poultry production. Probiotics are defined as "live microorganisms that, when administered in adequate amounts, confer a health benefit on the host." They are available in various forms for use as feed additives. Probiotics as feed additives aid in proper digestion of feed hence make the nutrients available for faster growth. Immunity can also be improved by addition of probiotics to poultry diets. Moreover, probiotics aid in improving meat and egg quality traits. Various infectious diseases of poultry can be countered by use of probiotics in their feed. A proper selection of probiotic strains is required for gaining optimal effects. This review focuses on the mechanisms of action of probiotics and their importance in poultry feed supplementation for enhancing production and safeguarding health of poultry.
Comparative study on the toxic effects of some heavy metals on the Nile Tilapia, Oreochromis niloticus , in the Middle Delta, Egypt
Abstract
Heavy metals are the most dangerous hazards affecting aquatic biota in Egypt specially the Nile Tilapia, Oreochromis niloticus, which is an important species in commercial fisheries. Some areas were not fully studied to screen the hazards that may affect this economic fish. Therefore, the present study aimed to evaluate the potential hazards of heavy metals on O. niloticus in Al-Gharbiya Governorate in the Middle delta of Egypt. Water and fish samples were collected from Al-Qased canal, Kafr El-Zayaat Nile, El-Maash canal in Al-Gharbiya Governorate plus a reference site which is a fish farm at the Faculty of Agriculture, Damietta University, Damitta Governorate, Egypt. The results showed a significant increase (p < 0.05) in the lead, zinc, magnesium, manganese, and copper levels while showed a significant decrease (p < 0.05) in the iron level in the water from all the investigated areas. Cadmium level was significantly high (p < 0.05) in Kafr El-Zayaat Nile and EL-Maash canal only. These metals were also accumulated in the fish livers and gills. Consequently, ALT and AST activities and creatinine level were significantly (p < 0.05) high in all the investigated areas. Histopathological examination revealed cytoplasmic and nuclear degeneration in the hepatocytes in all the investigated areas. Renal glomeruli and Bowman's capsule were not completely intact in Al-Qased and El-Maash canals while conspicuous shrinkage of the glomeruli was determined in Kafr El-Zayaat Nile. Furthermore, slight damage in the secondary lamellae was detected in the gill from Al-Qased canal while in the other areas appeared vacuolated or destructed. Finally, spleen sections of fish from different sites showed the absence of melanin pigments and some vacuoles. In conclusion, the Nile Tilapia, Oreochromis niloticus, is affected by the toxic effects of the heavy metals in Al-Gharbiya Governorate in Egypt and this gives an alarm and should be taken into consideration.
A dual-permeability hydro-biodegradation model for leachate recirculation and settlement in bioreactor landfills
Abstract
A dual-permeability hydro-biodegradation model is developed to describe the leachate flow in municipal solid waste (MSW) and predict the long-term settlement induced by biodegradation in bioreactor landfills. The model is verified against Hydrus-1D and a recirculation experiment conducted in a full-scale landfill. Preferential flow and mass transfer between fissure and matrix can be reasonably modeled by the proposed model. A higher recirculation flow rate can speed up the stabilization process of landfill. However, too much recirculation leachate is not economical and environmental friendly. A stabilization speed index and a leachate utilization index are adopted to evaluate the stabilization speed of bioreactor landfill and utilization rate of leachate, respectively, and the optimal recirculation flow rate is estimated. A flow rate of q = 5 × 10−5–5 × 10−4 m/h (equivalent to recirculation intensity of Q = 15–150 L/tonwaste/year) is recommended for recirculation, which has been verified by the field data in numerous bioreactor landfills.
Performance and efficiency of removal of pharmaceutical compounds from hospital wastewater by lab-scale biological treatment system
Abstract
The fate of pharmaceuticals after discharged from hospital into wastewater was clarified experimentally by using a new lab-scale conventional activated sludge (CAS) treatment reactor. The 43 target compounds belong to nine therapeutic classes (antivirals, antibacterials, anticancer drugs, psychotropics, antihypertensives, analgesic–antipyretics, contrast media, herbal medicines, and phytoestrogens) were selected with inclusion of 16 newly estimated compounds. The efficiency of the present reactor was estimated by comparing the reaction rate constant of the solid-water partition coefficients (log Kd) between liquid and solid samples and half-life during 48-h experiment obtained by using hospital effluents with those obtained by using STP wastewater. The results that no significant difference in removal efficiency was observed between both water samples (P > 0.05) indicate high reliability of the present lab-scale reactor. The actual rates of removal when hospital effluent was applied varied widely (mean, 59 ± 40%) independent of type of the pharmaceuticals. More than 90% of 17 compounds were removed after 8 h of treatment. However, the values for psychotropics (mean, 19 ± 26%) and contrast media (mean, 24 ± 17%) were generally low, indicating high stability. The log Kd values ranged from 1.3 to 4.8. Notably, clarithromycin, acridine, and glycitein could be removed in both liquid and solid phases. The dominant removal mechanisms were found to be different for individual pharmaceutical. These results suggest the effectiveness of introduction of the lab-scale biological treatment system for development of a new solution for discharge of pharmaceuticals from hospital.
Effect of compression ratio, nozzle opening pressure, engine load, and butanol addition on nanoparticle emissions from a non-road diesel engine
Abstract
Currently, diesel engines are more preferred over gasoline engines due to their higher torque output and fuel economy. However, diesel engines confront major challenge of meeting the future stringent emission norms (especially soot particle emissions) while maintaining the same fuel economy. In this study, nanosize range soot particle emission characteristics of a stationary (non-road) diesel engine have been experimentally investigated. Experiments are conducted at a constant speed of 1500 rpm for three compression ratios and nozzle opening pressures at different engine loads. In-cylinder pressure history for 2000 consecutive engine cycles is recorded and averaged data is used for analysis of combustion characteristics. An electrical mobility-based fast particle sizer is used for analyzing particle size and mass distributions of engine exhaust particles at different test conditions. Soot particle distribution from 5 to 1000 nm was recorded. Results show that total particle concentration decreases with an increase in engine operating loads. Moreover, the addition of butanol in the diesel fuel leads to the reduction in soot particle concentration. Regression analysis was also conducted to derive a correlation between combustion parameters and particle number emissions for different compression ratios. Regression analysis shows a strong correlation between cylinder pressure-based combustion parameters and particle number emission.
As(V) and Sb(V) co-adsorption onto ferrihydrite: synergistic effect of Sb(V) on As(V) under competitive conditions
Abstract
Competitive adsorption of As(V) and Sb(V) at environmentally relevant concentrations onto ferrihydrite was investigated. Batch experiments and XPS analyses confirmed that in a binary system, the presence of Sb(V) exhibited a slight synergistic effect on As(V) adsorption. XPS analyses showed that As(V) and Sb(V) adsorption led to obvious diminishment of Fe–O–Fe and Fe–O–H bonds respectively. At pH of 9, a more significant decrease of Fe–O–Fe was observed in the binary system than that in a single system, indicating that As(V) displayed an even stronger interaction with lattice oxygen atoms under competitive conditions. Basically, ionic strength demonstrated a negligible or positive influence on As(V) and Sb(V) adsorption in binary system. Study of adsorption sequence also indicated that the presence of Sb(V) showed a promotion effect on As(V) adsorption at neutral pHs. Considering that co-contamination of As and Sb in waters has been of great concern throughout the world, our findings contributed to a better understanding of their distribution, mobility, and fate in environment.
A Note on G-Estimation of Causal Risk Ratios
Applying Multiple Statistical Methods to Derive an Index of Dietary Behaviors Most Related to Obesity
Silver Oxysalts Promote Cutaneous Wound Healing Independent of Infection
Abstract
Chronic wounds often exist in a heightened state of inflammation whereby excessive inflammatory cells release high levels of proteases and reactive oxygen species (ROS). While low levels of ROS play a fundamental role in the regulation of normal wound healing, their levels need to be tightly regulated to prevent a hostile wound environment resulting from excessive levels of ROS. Infection amplifies the inflammatory response, augmenting levels of ROS which creates additional tissue damage that supports microbial growth. Antimicrobial dressings are used to combat infection; however, the effects of these dressing on the wound environment and healing independent of infection are rarely assessed. Cytotoxic or adverse effects on healing may exacerbate the hostile wound environment and prolong healing. Here we assessed the effect on healing independent of infection of silver oxysalts which produce higher oxidative states of silver (Ag2+/Ag3+). Silver oxysalts had no adverse effect on fibroblast scratch wound closure whilst significantly promoting closure of keratinocyte scratch wounds (34% increase compared to control). Furthermore, dressings containing silver oxysalts accelerated healing of full-thickness incisional wounds in wild-type mice, reducing wound area, promoting re-epithelialisation and dampening inflammation. We explored the mechanisms by which silver oxysalts promote healing and found that unlike other silver dressings tested, silver oxysalt dressings catalyse the breakdown of hydrogen peroxide to water and oxygen. In addition, we found that silver oxysalts directly released oxygen when exposed to water. Collectively, these data provide the first indication that silver oxysalts promote healing independent of infection and may regulate oxidative stress within a wound through catalysis of hydrogen peroxide. This article is protected by copyright. All rights reserved.
Bacterial community changes in response to oil contamination and perennial crop cultivation
Abstract
We investigated bacterial community dynamics in response to used motor oil contamination and perennial crop cultivation by 16S rRNA gene amplicon sequencing in a 4-year field study. Actinobacteria, Proteobacteria, Chloroflexi, Acidobacteria, and Gemmatimonadetes were the major bacterial phyla, and Rhodococcus was the most abundant genus. Initially, oil contamination decreased the overall bacterial diversity. Actinobacteria, Betaproteobacteria, and Gammaproteobacteria were sensitive to oil contamination, exhibiting clear succession with time. However, bacterial communities changed over time, regardless of oil contamination and crop cultivation. The abundance difference of most OTUs between oil-contaminated and non-contaminated plots remained the same in later sampling years after the initial abundance difference induced by oil spike. The abundances of three oil-favored actinobacteria (Lysinimonas, Microbacteriaceae, and Marmoricola) and one betaproteobacterium (Aquabacterium) changed in different manner over time in oil-contaminated and non-contaminated soil. We propose that these taxa are potential bio-indicators for monitoring recovery from motor oil contamination in boreal soil. The effect of crop cultivation on bacterial communities became significant only after the crops achieved stable growth, likely associated with plant material decomposition by Bacteroidetes, Armatimonadetes and Fibrobacteres.
Control Banding Tools for Engineered Nanoparticles: What the Practitioner Needs to Know
Annals of Work Exposures and Health Performance, 2017
Exposure to hexavalent chromium in welders: Results of the WELDOX II field study
Characterization of the Selective Recording of Workplace Exposure Measurements into OSHA’s IMIS Databank
Evaluating the Risk of Noise-Induced Hearing Loss Using Different Noise Measurement Criteria
The Effect of Workforce Mobility on Intervention Effectiveness Estimates
Effects of Personal Protective Equipment Use and Good Workplace Hygiene on Symptoms of Neurotoxicity in Solvent-Exposed Vehicle Spray Painters
Optimal Cut-Off Points for the Short-Negative Act Questionnaire and Their Association with Depressive Symptoms and Diagnosis of Depression
Combining Environmental Investigation and a Dual-Analytical Strategy to Isolate the Legionella longbeachae Strain Linked to Two Occupational Cases of Legionellosis
Evaluation of 1-Nitropyrene as a Surrogate Measure for Diesel Exhaust
Improving the UNC Passive Aerosol Sampler Model Based on Comparison with Commonly Used Aerosol Sampling Methods
Teaching & Learning Tips 6: The flipped classroom
Abstract
Challenge: The "flipped classroom" is a pedagogical model in which instructional materials are delivered to learners outside of class, reserving class time for application of new principles with peers and instructors. Active learning has forever been an elusive ideal in medical education, but the flipped class model is relatively new to medical education. What is the evidence for the "flipped classroom," and how can these techniques be applied to the teaching of dermatology to trainees at all stages of their medical careers?
Κυριακή 11 Μαρτίου 2018
Successful therapy of ocular rosacea with topical ivermectin
Approximately 75% of cutaneous rosacea patients also suffer from an ocular involvement with blepharitis and meibomian gland dysfunction often presented as chalazia. Clinical symptoms are foreign body sensation, light sensitivity, burning and tearing.
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FOSB immunoreactivity in endothelia of epithelioid hemangioma (angiolymphoid hyperplasia with eosinophilia)
Background
Accurate distinction of epithelioid hemangioma (EH) from its malignant mimics is paramount but it remains challenging due to its wide morphological spectrum and lack of objective molecular markers. FOSB oncogenic activation was recently identified as a key event in endothelial proliferation. We sought to investigate the FOSB staining pattern in EH with angiolymphoid hyperplasia with eosinophilia morphology (EH-AHLE) and to evaluate its value in differential diagnosis of epithelioid vascular tumors.
Methods
From the authors' files, 15 representative cases of EH-ALHE were selected and evaluated for their FOSB immunostaining pattern. Other vascular proliferations which can be morphological mimics were also tested: epithelioid hemangioendothelioma (EHE) (5 cases) and epithelioid angiosarcoma (EAS) (5 cases).
Results
All 15 cases of EH-ALHE showed strong and homogeneous FOSB nuclear positivity in endothelial cells with ample cytoplasm and intracytoplasmic vacuoles. All cases of EHE and EAS lacked FOSB immunoreactivity or showed only incidental weak FOSB immunoreactivity in less than 5 nuclei per lesion.
Conclusions
FOSB immunohistochemistry is sensitive in the diagnosis of EH-ALHE, and allows differentiation from its histological mimics. An immunohistochemical panel including not only pan-cytokeratin AE1/AE3 and endothelial markers, but also FOSB, helps in the diagnosis of epithelioid vascular tumors.
Botulinum Toxin Type A: Assessing The Effects on The Brain Stem
Abstract
Background
In this study, our aim is to investigate the possible effects of Botulinum toxin type A administrations in the early and late periods on the brain stem.
Methods
Eighteen white New Zealand rabbits were used in this study with the subjects being divided into three groups. Group I received 0.05 mL sterile saline to the left anterior auricular muscles. Group II and III were injected with Botulinum toxin type A (Botox, Allergan) to the left anterior auricular muscles. Group II was sacrificed 5 days after application and Group III was sacrificed 12 weeks after application; brain stem tissues were then taken. The samples were examined with Caspase 3, 8, and 9 immunohistochemical stainings.
Results
In the control group with Caspase-3 immune staining, moderate-to-strong immune reactivity was seen in a small number of neurons. In the Caspase-8 and 9 immune stainings, the immune reactive neurons were seen in greater numbers when compared with the Caspase-3 immune reactive neurons. In the early and late period, groups with Caspase-8 and 9 immune stainings, the immune reactive neurons were seen in greater numbers and in the wider area when compared with the Caspase-3 immune reactive neurons. No significant differences were recognized in the Caspase immune stainings between the early and late period groups. The results were statistically supported.
Conclusion
It was concluded that Botulinum toxin type A application did not trigger apoptosis in stem cell tissues.
No Level Assigned
This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
Nanofat Increases Dermis Thickness and Neovascularization in Photoaged Nude Mouse Skin
Abstract
Object
To investigate the effects of nanofat injection into photoaged nude mouse skin on dermis thickness, neovascularization, and cell proliferation.
Methods
Adipose-derived stem cells (ADSCs) and nanofat were prepared from human liposuction aspirates. The photoaged skin model was created using ultraviolet B (UVB) radiation onto BALB/c nude mice. A total of 24 mice were used in this study; 6 mice without treatment (natural aging) served as controls, while 18 mice were irradiated under the UVB lamp and treated with PBS (200 μl per injection area), ADSCs (1 × 106/200 μl ADSCs per injection area), or nanofat (200 μl per injection area) on the dorsal skin. Four weeks after injection, skin specimens were collected. The skin texture of each group was evaluated by general observation. Histological analyses were performed to analyze skin structure, dermis thickness, collagen fiber arrangement, capillary density, and cell proliferation.
Results
Four weeks after injection, no obvious differences were observed between the PBS group, ADSCs group, and nanofat group by skin gross observation. From the histological analyses, the ADSCs group and the nanofat group showed obviously thicker dermis than the PBS group (P < 0.05). More capillaries were observed in skin using anti-CD31 staining in the ADSCs and Nanofat groups than was observed in the PBS group (P < 0.05). No significant differences in the average dermis proliferation index were observed between groups by anti-Ki-67 staining. However, an increased epidermal proliferation index was observed in the ADSCs and Nanofat groups, compared to that in the PBS group (P < 0.05).
Conclusions
Nanofat increased dermis thickness and neovascularization in photoaged skin.
No Level Assigned
This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
Clinical Application of Platelet-Rich Fibrin in Plastic and Reconstructive Surgery: A Systematic Review
Abstract
Background
Platelet-rich fibrin (PRF) has been applied in the clinical field for more than a decade, but largely in oral surgery and implant dentistry. Its utilization in plastic and reconstructive surgery is limited and lacking a comprehensive review. Hence, this article focuses on the various clinical applications of PRF pertaining to the plastic and reconstructive field through a systematic review.
Methods
In this review, articles describing the clinical application of PRF in plastic and reconstructive surgery were screened using predetermined inclusion and exclusion criteria. The articles were summarized and divided into groups based on the utilization of PRF. The effects and complications of PRF were analyzed and concluded.
Results
Among the 634 articles searched, 7 articles describing 151 cases are eligible. PRF was applied on 116 (76.8%) wounds to facilitate tissue healing, and the complete wound closure rate was 91.4% (106/116). Otherwise, PRF was applied in 10 (6.6%) cases of zygomaticomaxillary fracture to reconstruct orbital floor defects and in 25 (16.6%) cases of facial autologous fat grafts to increase the fat retention rate successfully. There is no report of PRF-related complications.
Conclusions
PRF could facilitate wound healing, including the healing of soft tissues and bony tissues, and facilitate fat survival rate. Further studies are needed to test the mechanism of PRF and expand its scope of application in plastic and reconstructive surgery.
Level of Evidence III
This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
Commentary on: Dorsal Preservation: The Push Down Technique Reassessed
Dorsal Preservation: The Push Down Technique Reassessed
The Preservation Rhinoplasty: A New Rhinoplasty Revolution
Comments on “Double-Blind Comparison of Ultrasonic and Conventional Osteotomy in Terms of Early Postoperative Edema and Ecchymosis”
Response to “Does Stromal Vascular Fraction Supplementation Improve Facial Lipotransfer?”
Response to “Comments on ‘Double-Blind Comparison of Ultrasonic and Conventional Osteotomy in Terms of Early Postoperative Edema and Ecchymosis’”
Response to “The Micromort Concept and its Applicability to Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL) Risk Assessment”
Response to “Comments on ‘Nonsurgical Medical Penile Girth Augmentation: Experience-Based Recommendations’”
The Micromort Concept and its Applicability to Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL) Risk Assessment
Comments on “Nonsurgical Medical Penile Girth Augmentation: Experience-Based Recommendations”
ASJ’s Position on Publishing Papers That Discuss Off-Label Product Usage
Does Stromal Vascular Fraction Supplementation Improve Facial Lipotransfer?
Aesthetic Refinements in C-V Flap: Raising a Perfect Cylinder
Commentary on: Incidence and Predictors of Venous Thromboembolism in Abdominoplasty
Facial Plastic Surgery Clinics of North America: Functional Rhinoplasty
Commentary on: Adipose-Derived Stem Cells in Aesthetic Surgery: A Mixed Methods Evaluation of the Current Clinical Trial, Intellectual Property, and Regulatory Landscape
Incidence and Predictors of Venous Thromboembolism in Abdominoplasty
Scarless Breast Reconstruction: Indications and Techniques for Optimizing Aesthetic Outcomes in Autologous Breast Reconstruction
Summary: Breast reconstruction that leaves no visible scars on the breast is possible for a subset of patients. This article reviews a cohort of 10 patients who underwent 14 autologous breast reconstructions. To achieve a reconstruction without visible breast scars, the mastectomy and autologous reconstruction are carried out through a periareolar incision. At the completion of the reconstruction, a small skin paddle is externalized through the mastectomy incision and in a subsequent stage entirely incorporated into a nipple areola reconstruction. Following completion of the breast and nipple areola reconstruction, a tattoo is performed that extends beyond the perimeter of the reconstructed areola and conceals all scars on the breast mound. The ideal candidate for this technique has a small or medium size breast, which is non- or minimally ptotic, and a donor site that can yield a flap larger than the volume of the native breast. In properly selected patients, this technique consistently yields high-quality results, which match or even surpass the aesthetics of the original breast.Reexploring the Anatomy of the Distal Humerus for its Role in Providing Vascularized Bone
Background: The lateral arm flap is used for composite defects in need of vascularized soft tissue, skin, and bone. From its original description, the distal humeral metaphysis can be included with the flap, supplied by the periosteal extensions of the posterior branch of the radial collateral artery. We sought to reexplore the anatomy of the lateral arm to determine its utility as a donor site for vascularized bone. Methods: Twelve fresh, silicone-injected cadaver dissections were performed. Arteriovenous anatomy, pedicle length and diameter, and anatomic variability as well as photo documentation was recorded. Results: The distal extent of the deltoid, lateral intermuscular septum and lateral humeral epicondyle were identified before the dissection. A septocutaneous perforator was consistently located 10 cm proximal to the lateral humeral epicondyle, which could be used for a skin paddle to monitor. Harvest of a 1.5 cm × 2 cm corticocancellous bone graft was performed. Average pedicle length was 9.1 ± 1.1 cm, and average pedicle diameter was 1.74 ± 0.52 mm. The inferior lateral cutaneous nerve of the arm and the posterior cutaneous nerve of the forearm were consistently identified and preserved. Conclusion: The predictable anatomy of the lateral distal humerus make it an ideal donor site for small segments of vascularized bone.Novel compound heterozygous mutations in KREMEN1 confirm it as a disease gene for ectodermal dysplasia
Abstract
Ectodermal dysplasia (ED) is a heterogeneous group of disorders caused by mutations in at least thirteen genes. Recently, a study reported Palestinian patients with ED from consanguineous families with a homozygous mutation in KREMEN1 (Kringle-containing transmembrane protein 1) and proposed it to be a causative gene for the autosomal recessive ED 13, hair/tooth type (ECTD13; OMIM #617392). A Thai family, parents and two children affected with ED, was recruited. The study was exempted from review by the Institutional Review Board, Faculty of Medicine, Chulalongkorn University (IRB584/60). Written informed consents of each participant were obtained according to the Declaration of Helsinki. Mutation analyses were performed as described previously.
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Pulmonary function in subjects with psoriasis: A cross-sectional population study
Abstract
Psoriasis is a prevalent chronic inflammatory disease associated with comorbidities, e.g. cardiometabolic diseases, inflammatory bowel disease, and depression that may share an inflammatory origin. Smoking increases the risk of psoriasis and the disease has also been linked to chronic obstructive pulmonary disease (COPD) and asthma, with evidence of shared inflammatory cytokine-mediated mechanisms. Moreover, subjects with psoriasis display increased risk of infections, especially respiratory infections including pneumonia. However, only a small single-center study of pulmonary function in subjects with psoriasis is available.
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Recurrent erysipelas of the face with hyperimmune reaction to group C streptococcus
Abstract
We present the case of a 73-year-old-woman, admitted in 2014 for n erysipelas of the face (figure 1a) beginning 3 days before, with red oedematous papules of the left temple, hyperthermia and chills the day after. Clinical examination did not find lymphadenopathy or skin lesion especially at her left ear. Blood samples showed a raised C reactive protein (CRP) to 120 mg/L without leukocytosis. Antinuclear antibodies were negative. Viral serologies (HIV, hepatitis C and B, EBV, parvovirus B19, VZV, mumps), viral PCR assay (EBV, parvovirus B19, CMV, VZV) and bacterial blood cultures were all negative Histopathological findings revealed a reactive infiltrate without vasculitis and necrosis.
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Differential blood cellular profile in patients with moderate to severe psoriasis treated with classical systemic therapies: A step forward in personalised medicine
Abstract
patients with moderate to severe psoriasis are difficult to treat with topical therapy only and they usually require additional systemic therapy. Despite this, a significant percentage of patients on these therapies shows an inadequate response to these drugs. Treatment decisions are often difficult as they usually rely on subjective terms. Therefore, finding indicators that predict efectiveness or failure to classical systemic therapy is an urgent need. The objective of this study was to analyse whether the phenotype of peripheral blood mononuclear cells (PBMC) would be different in responder or non-responder patients to classical systemic therapy, and thus could be used as a efectiveness predictor of this therapy effectiveness. These predictor markers could help physicians to choose the best individualised treatment for psoriasis patients.
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Cutaneous squamous cell carcinomas are associated with basal proliferating actinic keratoses
Abstract
Background
In addition to the extent of atypical keratinocytes throughout the epidermis, actinic keratoses (AKs) are histologically characterized by downward directed basal layer expansion. It is not known if this growth pattern correlates with the risk of developing invasive squamous cell carcinoma (iSCC).
Objective
To characterize the prevalence of downward directed basal layer expansion of AKs adjacent to iSCC.
Methods
The epidermis overlying and adjacent to iSCCs was assessed histologically. We determined the histological grade (AKI-III), basal growth pattern (PROI-III) and accompanying parameters such as adnexal involvement.
Results
Of 307 lesions, 52.4% of AKs were histologically classified as AKI, 38.1% as AKII, and 6.8% as AKIII (chi-squared; P<0.0001). 2.6% of adjacent epidermis did not show any atypical keratinocytes. The epidermis adjacent to iSCCs was classified as having a PROI basal growth pattern in 25.7%, PROII in 31.9%, and PROIII in 39.4% cases. 2.9% of AKs showed no basal growth (chi-squared; P<0.0001).118 (48.8%) AKs showed extension into adnexal structures. These AKs were graded as PROI in 18.6%, PROII in 30.5%, and PROIII in 50.8%. The epidermis above iSCCs could only be assessed for upwards directed growth and showed no significant differences in the three AK grades (P=0.4211).
Conclusions
Basal proliferative AKs as well as atypical keratinocytes restricted to the lower third of the epidermis are most commonly seen adjacent to iSCC with less evidence for full thickness epidermal dysplasia. Our study supports the important role of dysplastic keratinocytes in the epidermal basal layer and their potential association with iSCC.
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Population-based prevalence of Eosinophilic (Shulman's) Fasciitis: a capture-recapture study
Abstract
Our knowledge of Eosinophilic fasciitis (EF), also known as Shulman's syndrome, is limited, and its prevalence has not been estimated so far. We conducted a regional survey which aimed at estimating the prevalence of EF in Alsace, a Region in the North-East of France. We retrospectively collected EF cases from the first of January 1983 to the 30th of March 2015 among Alsace residents aged >18 years, then performed a capture-recapture analysis with the prevalent cases in 2015.
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On the Mechanism of Photodehydrogenation of Aryl(hetaryl)pyrazolines in the Presence of Perchloroalkanes
Abstract
New (1,5-diaryl-3-pyrazolinyl)coumarins have been synthesized. In opposite to (1,5-diaryl-3-pyrazolinyl)-4-hydroxycoumarins these compounds are not able to keto-enol tautomeric transformations with changes of the solvent. (1,5-Diaryl-3-pyrazolinyl)coumarins provide dehydrogenation reaction under irradiation in the presence of perchloroalkanes and manifest themselves as effective photogenerators of acidity. Several aspects of photodehydrogenation mechanism have been studied. Oxygen is shown not be involved in the reaction. Polar solvents increase rate of the reaction. The measured rate constants of the photodehydrogenation reactions vary in a significant range according to the structure of pyrazoline. The data correlate with ionization potentials of pyrazolines available from DFT quantum chemical calculations. These results are discussed in terms of proposed scheme of mechanism of pyrazolines photodehydrogenation assuming formation of ion-radical and ion intermediates.
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Σάββατο 10 Μαρτίου 2018
Sorption of selected pharmaceuticals by a river sediment: role and mechanisms of sediment or Aldrich humic substances
Abstract
Sorption of pharmaceuticals onto sediments is frequently related to organic matter content. Thus, the present work aimed to compare the effect of humic substances (HS) extracted from a river sediment versus Aldrich (HS) on the sorption of selected pharmaceuticals onto this river sediment. The results exhibited no "unique" effect of the presence of HS from the same origin. Thus, the sediment HS increased the sorption of sulfamethoxazole (SMX), diclofenac (DCF), and trimethoprim (TMP), but reduced the sorption of atenolol (ATN). The presence of Aldrich HS increased the sorption of TMP and ATN and decreased the sorption of SMX and DCF. Fluorescence quenching measurements revealed that these effects cannot be explained only by the presence of pharmaceutical HS associations. The use of several sorption models suggested that the sorption of SMX, DCF, and ATN involves multilayer mechanisms. Furthermore, it was pointed out that the presence of HS does not change the sorption mechanisms although it was observed interaction between HS and the sediment. Indeed, the sediment HS sorbs onto the sediment whereas the Aldrich HS tends to mobilize organic compounds from the sediment to the solution.
Modes of selenium occurrence and LCD modeling of selenite desorption/adsorption in soils around the selenium-rich core, Ziyang County, China
Abstract
Studying the modes of selenium occurrence in high-Se soils and its behaviors can improve understanding and evaluating its cycling, flux, and balance in geo-ecosystems and its influence on health. In this paper, using a modified sequential chemical extraction technique, seven operationally defined selenium fractions and Se valence distribution were determined about five soils in which paddy was planted (W1, W2, W3, W4, W5) and five soils in which maize was planted (H1, H2, H3, H4, H5) around the selenium-rich core, Ziyang County, Shaanxi Province, China. The results show that selenium fractions in the soils mainly include sulfide/selenide and base-soluble Se, and ligand-exchangeable Se is also high for five soils in which paddy was planted. For water-soluble Se, Se (IV) is main Se valence and almost no Se (VI) was determined about five soils in which paddy was planted, while almost 1:1 of Se (IV) and Se (VI) coexist about five soils in which maize was planted. For exchangeable Se, similar results were found. For the first time, two typical high-Se soils (W1 soil and H1 soil) were chosen to measure the pH-dependent solid-solution distribution of selenite in the pH range 3–9, and the results were explained using LCD (ligand and charge distribution) adsorption modeling. The desorbed selenite concentrations from the two soils are in general underestimated by the model due to a comparable binding affinity of phosphate and selenite on goethite and much lower amount of total selenite than total reactively adsorbed phosphate. The pH dependency of adsorption of selenite added to the soil can be successfully described with the LCD model for W1 soil. Whereas considering the influence of Al-oxides, by lowering selenite adsorption affinity constant K of Se adsorption on goethite by 16 times, the LCD model can describe the adsorption much better. The results can help to understand selenium cycling, flux, and balance in typical high-Se soils.
Distillers’ grains anaerobic digestion residue biochar used for ammonium sorption and its effect on ammonium leaching from an Ultisol
Abstract
The aim of this work was to explore the potential application of biochar from distillers' grains anaerobic digestion residue pyrolyzed at 700 °C (ADR-DG700) to ammonium (NH4+) adsorption from aqueous solution, as well as its effect on NH4+ leaching from an Ultisol. The adsorption kinetic of NH4+ on the ADR-DG700 could be described by an Elovich model (R2 = 0.995), and the combined Langmuir-Freundlich model (R2 = 0.997) fitted the isotherm data better than the Langmuir, Freundlich, Redlich-Peterson, and Temkin models with a maximum adsorption of 11.41 mg N g−1. The NH4+ adsorption on ADR-DG700 was mainly controlled by the cation exchange, the surface complexation with oxygen-containing functional groups of carboxyl C〓O (C▬O) and carbohydrate C▬OH, as well as the electrostatic interactions with Si▬O▬Si functional group. In addition, the ADR-DG700 soil application reduced 2.48–20.67% of NH4+-N leaching loss after nitrogen fertilizer application in an Ultisol. These results suggested that the ADR-DG700 could be a sorbent for NH4+-contaminated water as well as an inhibitor for soil NH4+ leaching.
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A Case of Diprosopus Tetraophthalmos: Ocular Findings and Surgical Treatment of Exposure KeratopathyDiprosopus is a rare variation of conjoined twinning. In this report, ophthalmic findings in an infant with diprosopus tetraophthalmos are p...
