Medicine by Alexandros G. Sfakianakis: 04/02/18

Δευτέρα 2 Απριλίου 2018

Age Differences in Perceptions of and Motivations for Voluntary Medical Male Circumcision Among Adolescents in South Africa, Tanzania, and Zimbabwe

Abstract

Background

The World Health Organization (WHO) and the Joint United Nations Programme on HIV/AIDS (UNAIDS) have set a Fast-Track goal to achieve 90% coverage of voluntary medical male circumcision (VMMC) among boys and men aged 10–29 years in priority settings by 2021. We aimed to identify age-specific facilitators of VMMC uptake among adolescents.

Methods

Younger (aged 10–14 years; n = 967) and older (aged 15–19 years; n = 559) male adolescents completed structured interviews about perceptions of and motivations for VMMC before receiving VMMC counseling at 14 service provision sites across South Africa, Tanzania, and Zimbabwe. Adjusted prevalence ratios (aPRs) were estimated using multivariable modified Poisson regression models with generalized estimating equations and robust standard errors.

Results

The majority of adolescents reported a strong desire for VMMC. Compared with older adolescents, younger adolescents were less likely to cite protection against human immunodeficiency virus (HIV) or other sexually transmitted infections (aPR, 0.77; 95% confidence interval [CI], .66–.91) and hygienic reasons (aPR, 0.55; 95% CI, .39–.77) as their motivation to undergo VMMC but were more likely to report being motivated by advice from others (aPR, 1.88; 95% CI, 1.54–2.29). Although most adolescents believed that undergoing VMMC was a normative behavior, younger adolescents were less likely to perceive higher descriptive norms (aPR, 0.79; .71–.89), injunctive norms (aPR, 0.86; 95% CI, .73–1.00), or anticipated stigma for being uncircumcised (aPR, 0.79; 95% CI, .68–.90). Younger adolescents were also less likely than older adolescents to correctly cite that VMMC offers men and boys partial HIV protection (aPR, 0.73; 95% CI, .65–.82). Irrespective of age, adolescents' main concern about undergoing VMMC was pain (aPR, 0.95; 95% CI, .87–1.04). Among younger adolescents, fear of pain was negatively associated with desire for VMMC (aPR, 0.89; 95% CI, .83–.96).

Conclusions

Age-specific strategies are important to consider to generate sustainable demand for VMMC. Programmatic efforts should consider building on the social norms surrounding VMMC and aim to alleviate fears about pain.

Perceived Quality of In-Service Communication and Counseling Among Adolescents Undergoing Voluntary Medical Male Circumcision

Abstract

Background

Experience with providers shapes the quality of adolescent health services, including voluntary medical male circumcision (VMMC). This study examined the perceived quality of in-service communication and counseling during adolescent VMMC services.

Methods

A postprocedure quantitative survey measuring overall satisfaction, comfort, perceived quality of in-service communication and counseling, and perceived quality of facility-level factors was administered across 14 VMMC sites in South Africa, Tanzania, and Zimbabwe. Participants were adolescent male clients aged 10–14 years (n = 836) and 15–19 years (n = 457) and completed the survey 7 to 10 days following VMMC. Adjusted prevalence ratios (aPRs) were estimated by multivariable modified Poisson regression with generalized estimating equations and robust variance estimation to account for site-level clustering.

Results

Of 10- to 14-year-olds and 15- to 19-year-olds, 97.7% and 98.7%, respectively, reported they were either satisfied or very satisfied with their VMMC counseling experience. Most were also very likely or somewhat likely (93.6% of 10- to 14-year olds and 94.7% of 15- to 19-year olds) to recommend VMMC to their peers. On a 9-point scale, the median perceived quality of in-service (counselor) communication was 9 (interquartile range [IQR], 8–9) among 15- to 19-year-olds and 8 (IQR, 7–9) among 10- to 14-year-olds. The 10- to 14-year-olds were more likely than 15- to 19-year-olds to perceive a lower quality of in-service (counselor) communication (score <7; 21.5% vs. 8.2%; aPR, 1.61 [95% confidence interval, 1.33–1.95]). Most adolescents were more comfortable with a male rather than female counselor and provider. Adolescents of all ages wanted more discussion about pain, wound care, and healing time.

Conclusions

Adolescents perceive the quality of in-service communication as high and recommend VMMC to their peers; however, many adolescents desire more discussion about key topics outlined in World Health Organization guidance.

Cover

Scaling Up Voluntary Medical Male Circumcision for Human Immunodeficiency Virus Prevention for Adolescents and Young Adult Men: A Modeling Analysis of Implementation and Impact in Selected Countries

Abstract

Background

The new World Health Organization and Joint United Nations Programme on HIV/AIDS strategic framework for voluntary medical male circumcision (VMMC) aims to increase VMMC coverage among males aged 10–29 years in priority settings to 90% by 2021. We use mathematical modeling to assess the likelihood that selected countries will achieve this objective, given their historical VMMC progress and current implementation options.

Methods

We use the Decision Makers' Program Planning Toolkit, version 2, to examine 4 ambitious but feasible scenarios for scaling up VMMC coverage from 2017 through 2021, inclusive in Lesotho, Malawi, Mozambique, Namibia, South Africa, Swaziland, Tanzania, Uganda, and Zimbabwe.

Results

Tanzania is the only country that would reach the goal of 90% VMMC coverage in 10- to 29-year-olds by the end of 2021 in the scenarios assessed, and this was true in 3 of the scenarios studied. Mozambique, South Africa, and Lesotho would come close to reaching the objective only in the most ambitious scenario examined.

Conclusions

Major changes in VMMC implementation in most countries will be required to increase the proportion of circumcised 10- to 29-year-olds to 90% by the end of 2021. Scaling up VMMC coverage in males aged 10–29 years will require significantly increasing the number of circumcisions provided to 10- to 14-year-olds and 15- to 29-year-olds.

Impact of Counseling Received by Adolescents Undergoing Voluntary Medical Male Circumcision on Knowledge and Sexual Intentions

Abstract

Background

Little is known regarding the impact of counseling delivered during voluntary medical male circumcision (VMMC) services on adolescents' human immunodeficiency virus (HIV) knowledge, VMMC knowledge, or post-VMMC preventive sexual intentions. This study assessed the effect of counseling on knowledge and intentions.

Methods

Surveys were conducted with 1293 adolescent clients in 3 countries (South Africa, n = 299; Tanzania, n = 498; Zimbabwe, n = 496). Adolescents were assessed on HIV and VMMC knowledge-based items before receiving VMMC preprocedure counseling and at a follow-up survey approximately 10 days postprocedure. Sexually active adolescents were asked about their sexual intentions in the follow-up survey. Prevalence ratios (PRs) and 95% confidence intervals (CIs) were calculated by modified Poisson regression models with generalized estimating equations and robust variance estimators.

Results

Regarding post-VMMC HIV prevention knowledge, older adolescents were significantly more likely than younger adolescents to know that a male should use condoms (age 10–14 years, 41.1%; 15–19 years, 84.2%; aPR, 1.38 [95% CI, 1.19–1.60]), have fewer sex partners (age 10–14 years, 8.1%; age 15–19 years, 24.5%; aPR, 2.10 [95% CI, 1.30–3.39]), and be faithful to one partner (age 10–14 years, 5.7%; age 15–19 years, 23.2%; aPR, 2.79 [95% CI, 1.97–3.97]) to further protect himself from HIV. Older adolescents demonstrated greater improvement in knowledge in most categories, differences that were significant for questions regarding number of sex partners (aPR, 2.01 [95% CI, 1.18–3.44]) and faithfulness to one partner post-VMMC (aPR, 3.28 [95% CI, 2.22–4.86]). However, prevention knowledge levels overall and HIV risk reduction sexual intentions among sexually active adolescents were notably low, especially given that adolescents had been counseled only 7–10 days prior.

Conclusions

Adolescent VMMC counseling needs to be improved to increase knowledge and postprocedure preventive sexual intentions.

Adolescent Male Circumcision for HIV Prevention in High Priority Countries: Opportunities for Improvement

Abstract

Global experts recognize the need to transform conventional models of healthcare to create adolescent responsive health systems. As countries near 80% coverage of voluntary medical male circumcision (VMMC) for those aged 15–49 years, prioritization of younger men becomes critical to VMMC sustainability. This special supplement reporting 9 studies focusing on adolescent VMMC programming and services comes at a critical time. Eight articles report how well adolescents are reached with the World Health Organization's minimum package for comprehensive human immunodeficiency virus (HIV) prevention in South Africa, Zimbabwe, and Tanzania, analyzing motivation, counseling, wound healing, parental involvement, female peer support, quality of in-service communication, and providers' perceptions, and one presents models for achieving high VMMC coverage by 2021. One important finding is that adolescent boys, especially the youngest, experience gaps in their comprehension of key elements in the World Health Organization's minimum package. Although parents, counselors, and providers are involved and supportive, they are inadequately prepared to counsel youth, partly owing to discomfort with adolescent sexuality. At the country level, deliberately prioritizing young adolescents (aged 10–14 years) is likely to achieve national coverage targets more quickly and cost-effectively than continuing to focus on older, harder-to-reach men. The studies in this supplement point to areas where VMMC programs are achieving successes and they reveal areas for improvement. Given that prioritizing adolescents will be the best means of achieving sustainable VMMC for HIV prevention for the foreseeable future, applying the lessons learned here will increase the effectiveness of VMMC programs.

Females’ Peer Influence and Support for Adolescent Males Receiving Voluntary Medical Male Circumcision Services

Abstract

Background

While female involvement in voluntary medical male circumcision (VMMC) has been studied among adults, little is known about the influence of adolescent females on their male counterparts. This study explored adolescent females' involvement in VMMC decision making and the postoperative wound healing process in South Africa, Tanzania, and Zimbabwe.

Methods

Across 3 countries, 12 focus group discussions were conducted with a total of 90 adolescent females (aged 16–19 years). Individual in-depth interviews were conducted 6–10 weeks post-VMMC with 92 adolescent males (aged 10–19 years). Transcribed and translated qualitative data were coded into categories and subcategories by 2 independent coders.

Results

Adolescent female participants reported being supportive of male peers' decisions to seek VMMC, with the caveat that some thought VMMC gives males a chance to be promiscuous. Regardless, females from all countries expressed preference for circumcised over uncircumcised sexual partners. Adolescent females believed VMMC to be beneficial for the sexual health of both partners, viewed males with a circumcised penis as more attractive than uncircumcised males, used their romantic relationships with males or the potential for sex as leveraging points to convince males to become circumcised, and demonstrated supportive attitudes in the wound-healing period. Interviews with males confirmed that encouragement from females was a motivating factor in seeking VMMC.

Conclusions

Adolescent female participants played a role in convincing young males to seek VMMC and remained supportive of the decision postprocedure. Programs aiming to increase uptake of VMMC and other health-related initiatives for adolescent males should consider the perspective and influence of adolescent females.

Counseling Received by Adolescents Undergoing Voluntary Medical Male Circumcision: Moving Toward Age-Equitable Comprehensive Human Immunodeficiency Virus Prevention Measures

Abstract

Background

The minimum package of voluntary medical male circumcision (VMMC) services, as defined by the World Health Organization, includes human immunodeficiency virus (HIV) testing, HIV prevention counseling, screening/treatment for sexually transmitted infections, condom promotion, and the VMMC procedure. The current study aimed to assess whether adolescents received these key elements.

Methods

Quantitative surveys were conducted among male adolescents aged 10–19 years (n = 1293) seeking VMMC in South Africa, Tanzania, and Zimbabwe. We used a summative index score of 8 self-reported binary items to measure receipt of important elements of the World Health Organization–recommended HIV minimum package and the US President's Emergency Plan for AIDS Relief VMMC recommendations. Counseling sessions were observed for a subset of adolescents (n = 44). To evaluate factors associated with counseling content, we used Poisson regression models with generalized estimating equations and robust variance estimation.

Results

Although counseling included VMMC benefits, little attention was paid to risks, including how to identify complications, what to do if they arise, and why avoiding sex and masturbation could prevent complications. Overall, older adolescents (aged 15–19 years) reported receiving more items in the recommended minimum package than younger adolescents (aged 10–14 years; adjusted β, 0.17; 95% confidence interval [CI], .12–.21; P < .001). Older adolescents were also more likely to report receiving HIV test education and promotion (42.7% vs 29.5%; adjusted prevalence ratio [aPR], 1.53; 95% CI, 1.16–2.02) and a condom demonstration with condoms to take home (16.8% vs 4.4%; aPR, 2.44; 95% CI, 1.30–4.58). No significant age differences appeared in reports of explanations of VMMC risks and benefits or uptake of HIV testing. These self-reported findings were confirmed during counseling observations.

Conclusions

Moving toward age-equitable HIV prevention services during adolescent VMMC likely requires standardizing counseling content, as there are significant age differences in HIV prevention content received by adolescents.

Parental Communication, Engagement, and Support During the Adolescent Voluntary Medical Male Circumcision Experience

Abstract

Background

Voluntary medical male circumcision (VMMC) is one of few opportunities in sub-Saharan Africa to engage male adolescents in the healthcare system. Limited data are available on the level of parental communication, engagement, and support adolescents receive during the VMMC experience.

Methods

We conducted 24 focus group discussions with parents/guardians of adolescents (N = 192) who agreed to be circumcised or were recently circumcised in South Africa, Tanzania, and Zimbabwe. In addition, male adolescents (N = 1293) in South Africa (n = 299), Tanzania (n = 498), and Zimbabwe (n = 496) were interviewed about their VMMC experience within 7–10 days postprocedure. We estimated adjusted prevalence ratios (aPRs) using multivariable Poisson regression with generalized estimating equations and robust standard errors.

Results

Parents/guardians noted challenges and gaps in communicating with their sons about VMMC, especially when they did not accompany them to the clinic. Adolescents aged 10–14 years were significantly more likely than 15- to 19-year-olds to report that their parent accompanied them to a preprocedure counseling session (56.5% vs 12.5%; P < .001). Among adolescents, younger age (aPR, 0.86; 95% confidence interval [CI], .76–.99) and rural setting (aPR, 0.34; 95% CI, .13–.89) were less likely to be associated with parental–adolescent communication barriers, while lower socioeconomic status (aPR, 1.37; 95% CI, 1.00–1.87), being agnostic (or of a nondominant religion; aPR, 2.87; 95% CI, 2.21–3.72), and living in South Africa (aPR, 2.63; 95% CI, 1.29–4.73) were associated with greater perceived barriers to parental–adolescent communication about VMMC. Parents/guardians found it more difficult to be involved in wound care for older adolescents than for adolescents <15 years of age.

Conclusions

Parents play a vital role in the VMMC experience, especially for younger male adolescents. Strategies are needed to inform parents completely throughout the VMMC adolescent experience, whether or not they accompany their sons to clinics.

Adolescent Wound-Care Self-Efficacy and Practices After Voluntary Medical Male Circumcision—A Multicountry Assessment

Abstract

Background

Adolescent boys (aged 10–19 years) constitute the majority of voluntary medical male circumcision (VMMC) clients in sub-Saharan Africa. They are at higher risk of postoperative infections compared to adults. We explored adolescents' wound-care knowledge, self-efficacy, and practices after VMMC to inform strategies for reducing the risks of infectious complications postoperatively.

Methods

Quantitative and qualitative data were collected in South Africa, Tanzania, and Zimbabwe between June 2015 to September 2016. A postprocedure survey was conducted approximately 7–10 days after VMMC among male adolescents (n = 1293) who had completed a preprocedure survey; the postprocedure survey assessed knowledge of proper wound care and wound-care self-efficacy. We also conducted in-depth interviews (n = 92) with male adolescents 6–10 weeks after the VMMC procedure to further explore comprehension of providers' wound-care instructions as well as wound-care practices, and we held 24 focus group discussions with randomly selected parents/guardians of the adolescents.

Results

Adolescent VMMC clients face multiple challenges with postcircumcision wound care owing to factors such as forgetting, misinterpreting, and disregarding provider instructions. Although younger adolescents stated that parental intervention helped them overcome potential hindrances to wound care, parents and guardians lacked crucial information on wound care because most had not attended counseling sessions. Some older adolescents reported ignoring symptoms of infection and not returning to the clinic for review when an adverse event had occurred.

Conclusions

Increased involvement of parents/guardians in wound-care counseling for younger adolescents and in wound-care supervision, alongside the development of age-appropriate materials on wound care, are needed to minimize postoperative complications after VMMC.

Providers’ Perceptions and Training Needs for Counseling Adolescents Undergoing Voluntary Medical Male Circumcision

Abstract

Background

The majority of individuals who seek voluntary medical male circumcision (VMMC) services in sub-Saharan Africa are adolescents (ages 10–19 years). However, adolescents who obtain VMMC services report receiving little information on human immunodeficiency virus (HIV) prevention and care. In this study, we assessed the perceptions of VMMC facility managers and providers about current training content and their perspectives on age-appropriate adolescent counseling.

Methods

Semistructured in-depth interviews were conducted with 33 VMMC providers in Tanzania (n = 12), South Africa (n = 9), and Zimbabwe (n = 12) and with 4 key informant facility managers in each country (total 12). Two coders independently coded the data thematically using a 2-step process and Atlas.ti qualitative coding software.

Results

Providers and facility managers discussed limitations with current VMMC training, noting the need for adolescent-specific guidelines and counseling skills. Providers expressed hesitation in communicating complete sexual health information—including HIV testing, HIV prevention, proper condom usage, the importance of knowing a partner's HIV status, and abstinence from sex or masturbation during wound healing—with younger males (aged <15 years) and/or those assumed to be sexually inexperienced. Many providers revealed that they did not assess adolescent clients' sexual experience and deemed sexual topics to be irrelevant or inappropriate. Providers preferred counseling younger adolescents with their parents or guardians present, typically focusing primarily on wound care and procedural information.

Conclusions

Lack of training for working with adolescents influences the type of information communicated. Preconceptions hinder counseling that supports comprehensive HIV preventive behaviors and complete wound care information, particularly for younger adolescents.

Title Page

Recognition of early melanoma: a monocentric dermoscopy follow‐up study comparing de novo melanoma with nevus‐associated melanoma

International Journal of Dermatology, EarlyView.

Long-term trends in Swiss rivers sampled continuously over 39 years reflect changes in geochemical processes and pollution

Abstract

Long-term changes of 14 water constituents measured in continuously and water discharge proportionally collected samples of four Swiss rivers over a period of 39 years are analyzed using several statistical techniques. Possible drivers and causes for the identified trends and shifts are explained by consideration of catchment characteristics and anthropogenic activities. Water temperatures increased by 0.8–1.3 °C, whereas water discharges remained largely unchanged. Concentrations of alkalinity, total hardness, Ca, and Mg regulated by dominant carbonate lithologies in catchments increased by up to 10%. We attribute this change to an increase in the partial pressure of CO₂ in the subsurface, provoked by increasing temperatures. Re-oligotrophication processes in lakes also influence the behavior of alkalinity and silicic acid. In contrast to concentrations, most loads did not change significantly, due to their large variances. Therefore, no changes in overall weathering rates of carbonate rocks can be detected. The outgassing of CO₂ in rivers from the place of carbonate dissolution to measurement stations amounts up to 6% (mean) of CO₂ sequestered (mean 1.1 mol m⁻² a⁻¹) by the weathering of rock minerals. Changes in alkalinity/Ca/Mg ratios indicate an increase in calcite precipitation over time. Total nitrogen concentrations and loads peaked at the end of the 1980s and then decreased up to 50%, while NO₃ concentrations showed almost no changes. This dynamic matches the changes in the agricultural N balance. Concentrations and loads of Na and Cl increased up to 60% due to an increase in the various uses of rock salt.

In This Issue

The levels of polycyclic aromatic hydrocarbons (PAHs) in human milk and exposure risk to breastfed infants in petrochemical industrialized Lanzhou Valley, Northwest China

Abstract

We investigated in this paper the presence of PAHs in human milk from lactating women residing in Lanzhou, a petrochemical industrialized valley city in Northwest China. The PAH concentration levels in human milk samples from 98 healthy women were determined by gas chromatography/mass spectrometry (GC/MS). The associations between the lifestyle factors and the PAHs levels of human milk were analyzed. Moreover, we applied principal component analysis (PCA) method to gain a better insight into the similarities or dissimilarities of the human milk PAH loads and different pathways of source exposure. In addition, the exposure risks of breastfed infants due to PAH ingestion via breast milk were assessed and the relative breast-feeding risk to the total intake dose of infants was addressed. The results showed that the average fat-normalized human milk ∑₁₅PAHs concentrations for the lactating women residing in four districts of Lanzhou, namely, Xigu, Anning, Qilihe, and Chengguan were 320.40, 270.36, 374.04, and 259.84 ng/g of fat, respectively. The ∑₁₅PAHs of human milk from the lactating women of Qilihe District exhibited the highest concentration level, while the concentration level for women from Xigu District is the second highest for the observed human milk ∑₁₅PAHs. And the corresponding BaPeq concentrations for women in Xigu, Anning, Qilihe, and Chengguan districts were 58.29, 47.95, 65.13, and 45.60 ng/g of fat, respectively. A significant correlation was only found between human milk and living district environment (p < 0.05). Although the Spearman correlation analysis showed that there were no significant correlation existing between other lifestyle and human milk PAHs, we confirmed that consuming barbecue food could elevate PAHs levels in human milk: the barbecue intake frequency caused 10% fluctuation of ∑₁₅PAHs concentration between high frequency and low frequency group in our study. Furthermore, the exposure to second-hand smoke can also increase the ∑₁₅PAHs levels in human milk by 4 to 11% here. Ingestion doses of PAHs by infants (19.37–77.75 ng kg⁻¹ day⁻¹) were much higher than the inhalation doses (2.83–16.48 ng kg⁻¹ day⁻¹), which indicated that the ingestion is the main exposure risk pathway for infants. Since there are limited guidelines and standards for PAHs ingestion dose in human milk by infant, we compared the ingestion dose of BaP with the upper bound estimates of BaP dietary exposure of 108 ng kg⁻¹ day⁻¹ for toddlers of ages between 1.5 and 2.5 years of age in the UK reported by Committee on Toxicity of Chemicals in Food (COT) and the data we obtained were lower than this upper bound. However, the estimated margin of exposure (MOE) values of BaP-MOE, PAH2-MOE, PAH4-MOE, and PAH8-MOE were smaller than 10,000 which indicated that there are potential hazard for breastfed infants consuming these human milk samples.

Does the application of silicon and Moringa seed extract reduce heavy metals toxicity in potato tubers treated with phosphate fertilizers?

Abstract

Two field trials were carried out in two successive agricultural seasons to study the possibility of using silicon (Si) and Moringa seed extract (MSE) for reducing heavy metal contamination resulting from phosphate fertilizers addition to potato tubers. A randomized complete block design experiment was performed using three replicates. Various sources of phosphate fertilizers as ordinary super phosphate and rock phosphate were added at rate of 100 kg P ha⁻¹ prior sowing. Silicon was added as potassium silicate (20% SiO₂) at rate of 6 L ha⁻¹, and MSE was also added at rate of 150 L ha⁻¹ in three equal doses with the 2nd, 4th, and 6th irrigations during the last 10 min of drip irrigation. Results indicated that the addition of phosphate fertilizers increased fresh tuber yield, dry weight yield, NPK uptake, catalase, peroxidase, superoxide dismutase, and glutathione reductase of potato either alone or combined with silicon and MSE. The accumulation rate of Cu, Cd, and Ni in potato was higher with the single addition of rock phosphate fertilizer compared with single addition of super phosphate fertilizer. The highest reduction (P < 0.05) in heavy metal accumulation in potato leaves and tubers as well as soil was found with MSE treatment plus super phosphate fertilizer. It is recommended to add MSE at a rate of 150 L ha⁻¹ along with fertilizing the potato crop with ordinary super phosphate fertilizer.

Identification and quantitation of semi-crystalline microplastics using image analysis and differential scanning calorimetry

Abstract

There are several techniques used to analyze microplastics. These are often based on a combination of visual and spectroscopic techniques. Here we introduce an alternative workflow for identification and mass quantitation through a combination of optical microscopy with image analysis (IA) and differential scanning calorimetry (DSC). We studied four synthetic polymers with environmental concern: low and high density polyethylene (LDPE and HDPE, respectively), polypropylene (PP), and polyethylene terephthalate (PET). Selected experiments were conducted to investigate (i) particle characterization and counting procedures based on image analysis with open-source software, (ii) chemical identification of microplastics based on DSC signal processing, (iii) dependence of particle size on DSC signal, and (iv) quantitation of microplastics mass based on DSC signal. We describe the potential and limitations of these techniques to increase reliability for microplastic analysis. Particle size demonstrated to have particular incidence in the qualitative and quantitative performance of DSC signals. Both, identification (based on characteristic onset temperature) and mass quantitation (based on heat flow) showed to be affected by particle size. As a result, a proper sample treatment which includes sieving of suspended particles is particularly required for this analytical approach.

Mode of action of nanoparticles against insects

Abstract

The employment of nanoparticles obtained through various synthesis routes as novel pesticides recently attracted high research attention. An impressive number of studies have been conducted to test their toxic potential against a wide number of arthropod pests and vectors, with major emphasis on mosquitoes and ticks. However, precise information on the mechanisms of action of nanoparticles against insects and mites are limited, with the noteworthy exception of silica, alumina, silver, and graphene oxide nanoparticles on insects, while no information is available for mites. Here, I summarize current knowledge about the mechanisms of action of nanoparticles against insects. Both silver and graphene oxide nanoparticles have a significant impact on insect antioxidant and detoxifying enzymes, leading to oxidative stress and cell death. Ag nanoparticles also reduced acetylcholinesterase activity, while polystyrene nanoparticles inhibited CYP450 isoenzymes. Au nanoparticles can act as trypsin inhibitors and disrupt development and reproduction. Metal nanoparticles can bind to S and P in proteins and nucleic acids, respectively, leading to a decrease in membrane permeability, therefore to organelle and enzyme denaturation, followed by cell death. Besides, Ag nanoparticles up- and downregulate key insect genes, reducing protein synthesis and gonadotrophin release, leading to developmental damages and reproductive failure. The toxicity of SiO₂ and Al₂O₃ nanoparticles is due to their binding to the insect cuticle, followed by physico-sorption of waxes and lipids, leading to insect dehydration. In the final section, insect nanotoxicology research trends are critically discussed, outlining major challenges to predict the ecotoxicological consequences arising from the real-world use of nanoparticles as pesticides.

Cutis laxa associated monoclonal gammopathy: 14 new cases and review of the literature

UVΑ pre-irradiation to P25 titanium dioxide nanoparticles enhanced its toxicity towards freshwater algae Scenedesmus obliquus

Abstract

There has recently been an increase in the usage of TiO₂ nanoparticles (NPs). P25 TiO₂ NPs, a mixture of anatase and rutile phase in 3:1 ratio, are generally used for photocatalytic applications because both phases exhibit a synergistic effect on the photocatalytic activity of the TiO₂ NPs. In the present study, increased toxicity of UVA-pre-irradiated P25 TiO₂ NPs on freshwater algae Scenedesmus obliquus was assessed under visible light and dark exposure conditions at actual low concentrations (0.3, 3 and 35 μM of Ti). Photocatalytic property of P25 TiO₂ NPs caused disaggregation of UVA-pre-irradiated NPs, thus significantly decreasing the mean hydrodynamic diameter (MHD) (188.74 ± 0.54 nm) than that of non-irradiated NPs (232.26 ± 0.44). This decrease in diameter of UVA-pre-irradiated NPs may increase its biological activity towards algal samples. All concentrations of pre-irradiated NPs, under both light and dark conditions, showed a significantly lesser cell viability (p < 0.001) when compared with non-irradiated NPs. Increased production of ROS, antioxidant enzymes and lipid peroxidation supported the viability data. Higher exopolysaccharide production and more nuclear damage were observed for pre-irradiated NPs. NP uptake was also more for the pre-irradiated NPs on treated samples when compared with non-irradiated NPs on treated samples, which, in turn, established the higher toxic potential of UVA-pre-irradiated TiO₂ NPs. This study improves our understanding of the toxic effects of UVA-pre-irradiated TiO₂ NPs on freshwater algae, thereby emphasising the need for ecological risk assessments of metal oxide nanoparticles in a natural experimental medium.

Immunocompetence analysis of the aquatic snail Lymnaea stagnalis exposed to urban wastewaters

Abstract

Wastewater treatment plant effluents from urban area are a well-known source of chronic multiple micropollution to the downstream living organisms. In this study, ecologically relevant laboratory-bred freshwater gastropods, Lymnaea stagnalis, were exposed for 29 days to raw effluents of a wastewater treatment plant in Lyon area (France). A time-course analysis of individual markers of immunocompetence (hemocyte density and viability, hemocyte NADPH activity, phenol oxidase activity, and capacity of phagocytosis) has shown slight trends of inflammatory-like responses induced by the 100% effluents. So far, no short-term hazard for L. stagnalis can be revealed. However, over the long term, such environmental stress-stimulating immune responses could provoke deleterious life history trade-offs because the immune system is known to be highly energy-consuming.

Experimental assessment and validation of quantification methods for cellulose content in municipal wastewater and sludge

Abstract

Cellulose, mostly in the form of toilet paper, forms a major component of the particulates in raw municipal wastewater, which could lead to significant consequences due to the potential accumulation of cellulosic fibers and slow biodegradability. Despite the sparse reports on cellulose content and degradation in wastewater and sludge, an accurate and validated method for its quantification in such matrices does not exist. In this paper, four different methods were compared including dilute acid hydrolysis, concentrated acid hydrolysis, enzymatic hydrolysis, and the Schweitzer reagent method. The Schweitzer reagent method, applied to municipal wastewater and sludge, was found to be a very robust and reliable quantification method in light of its reproducibility, accuracy, and ideal (100%) recovery. The determination of cellulose content is critical to understand its fate in wastewater treatment plants as well as improve sludge management and enhance resource recovery.

Morphological and functional responses of a metal-tolerant sunflower mutant line to a copper-contaminated soil series

Abstract

The potential use of a metal-tolerant sunflower mutant line for biomonitoring Cu phytoavailability, Cu-induced soil phytotoxicity, and Cu phytoextraction was assessed on a Cu-contaminated soil series (13–1020 mg Cu kg⁻¹) obtained by fading a sandy topsoil from a wood preservation site with a similar uncontaminated soil. Morphological and functional plant responses as well as shoot, leaf, and root ionomes were measured after a 1-month pot experiment. Hypocotyl length, shoot and root dry weight (DW) yields, and leaf area gradually decreased as soil Cu exposure rose. Their dose-response curves (DRC) plotted against indicators of Cu exposure were generally well fitted by sigmoidal curves. The half-maximal effective concentration (EC₅₀) of morphological parameters ranged between 203 and 333 mg Cu kg⁻¹ soil, corresponding to 290–430 μg Cu L⁻¹ in the soil pore water, and 20 ± 5 mg Cu kg⁻¹ DW in the shoots. The EC₁₀ for shoot Cu concentration (13–15 mg Cu kg⁻¹ DW) coincided to 166 mg Cu kg⁻¹ soil. Total chlorophyll content and total antioxidant capacity (TAC) were early biomarkers (EC₁₀: 23 and 51 mg Cu kg⁻¹ soil). Their DRC displayed a biphasic response. Photosynthetic pigment contents, e.g., carotenoids, correlated with TAC. Ionome was changed in Cu-stressed roots, shoots, and leaves. Shoot Cu removal peaked roughly at 280 μg Cu L⁻¹ in the soil pore water.

Issue Information

Dermatologic Therapy, Volume 31, Issue 2, March/April 2018.

Controls on the spatial distribution of iodine in groundwater in the Hebei Plain, China

Abstract

In the Hebei Plain of North China, 70% of the inhabitants depend on groundwater for drinking water. Little is known regarding high-iodine concentrations in groundwater because there have been few systematic studies on high levels of iodine in groundwater in this region. To help identify the mechanisms that control the spatial distribution of iodine in groundwater, 61 samples of shallow groundwater and 161 samples of deep groundwater were collected along a sample section from Taihang Mountain to the Bo Sea. There were four pockets of high-iodine concentrations along the sample section. As the groundwater depth increased, the ratio of undetected iodine decreased, and the ratio of high-iodine concentrations increased. The high-iodine concentrations in the groundwater reflect the geological and sedimentary settings, and were mainly controlled by pH and Eh. Iodine concentrations were particularly high when the pH was between 7.3 and 8.5, and there was an inflection point at 150 μg/L in the curve of the relationship between iodine concentrations and Eh.

A comprehensive air quality investigation at an aquatic centre: Indoor/outdoor comparisons

Abstract

Air quality and comfort parameters in a naturally ventilated aquatic centre were studied in relation to the outdoor pollution levels. Simultaneous measurements of PM 2.5, as well as of volatile organic compounds, were carried out for the indoor and outdoor environment of the aquatic centre. The chemical analysis of ionic species and trace elements associated with particulate matter was also performed. In addition, automated analyzer for NO₂ and O₃ was used in order to record the indoor and outdoor levels of these pollutants. Analysis of diurnal variation of the pollutants' concentration was applied to the collected data, allowing the identification of potential variation on the sources affecting the indoor air quality. PM 2.5 concentration was almost two times higher indoors than outdoors with average values of 13.96 and 6.78 μg/m³, respectively. Concerning the ion fraction of PM 2.5, SO₄²⁻ and Ca²⁺ were the ions with higher concentration indoors with values of 1.06 and 0.93 μg/m³, respectively, while the percentage of Cl⁻ to the PM 2.5 fraction of the indoor atmosphere (9%) was too high than outdoor ones (1%). These results showed that indoor air of swimming pool concerning PM 2.5 and ionic species is mainly affected by the chlorination process along with the comfort conditions (high relative humidity) created during the operation of the facility. The common volatile organic compound concentrations at indoor air are generally in higher levels, compared to the outdoor air with p,m-xylene and toluene to be the substances with the higher concentration for indoor and outdoor area, respectively (7.80 and 1.57 μg/m³); nevertheless, values were rather low compared with the findings of other studies. Also, they clearly demonstrate a diurnal variation as a result of poor ventilation during night. As it was expected, chloroform showed the highest concentration compared to the other volatile organic compounds with values ranging from 3.35 to 135.89 μg/m³, with an average of 54.50 μg/m³. Concerning the NO₂ concentration, indoor levels showed an increased pattern when the swimming pool was fully occupied, a fact that reveals a possible correlation. As an overall conclusion, the natural ventilation and the disinfection process seem to play a key role to the air quality of the indoor air of the aquatic centre.

Characteristics of menstrual versus non-menstrual migraine during pregnancy: a longitudinal population-based study

Migraine is a common headache disorder that affects mostly women. In half of these, migraine is menstrually associated, and ranges from completely asymptomatic to frequent pain throughout pregnancy.

Current and Emerging Therapeutic Targets for Metastatic Renal Cell Carcinoma

Abstract

Purpose of review

The treatment of advanced renal cell carcinoma has evolved dramatically over recent years. In this review, we will summarize current and emerging therapies based on molecular targets and provide insight into treatment strategy for metastatic renal cell carcinoma.

Recent findings

We have witnessed a paradigm shift in the therapeutic landscape as treatment was formerly reliant on cytokine-based agents which have now been replaced with therapies targeting angiogenesis, mammalian target of rapamycin pathways, and immune responses. These dramatic changes are primarily due to our improved understanding of the underlying mutations and molecular mechanisms leading to tumorigenesis and progression.

Summary

We now have targeted agents in the form of small-molecule tyrosine kinase inhibitors, monoclonal antibodies, and mTOR inhibitors. Moreover, immunotherapy-targeting checkpoints of T-lymphocyte activity has provided increased overall survival and a new class of agents with potential to radically change the treatment options. With these agents and their combination, durable responses are increasingly seen even though treatment resistance remains a huge challenge. New treatment strategies are rapidly developing and the therapeutic landscape is expected for further evolution.