The suitability of EBC-Pb as a new biomarker to assess occupational exposure to lead

Occupational exposure to lead (Pb) requires continuous surveillance to assure, as much as possible, safe and healthful working conditions. This study addresses the suitability of assessing Pb exposure in relevant workers using their exhaled breath condensate (EBC). This study enrolled workers of two different Pb processing industries characterized by moderate and high Pb exposure levels in the work environment, and a group of non-exposed individuals working in offices who served as baseline for Pb exposure. The EBC-Pb of workers reflected the Pb levels in the work environment of all three settings, although the relationship with B-Pb was not clear. The lack of correlation between EBC-Pb and B-Pb most probably indicates the time lag for Pb to enter in the two body pools. The EBC-Pb seems to reflect immediate exposure, providing a prompt signature of Pb in the environmental that may interact directly with the organ. By delivering short-term evaluation of exposure, EBC-Pb represents a clear advantage in biomonitoring and may become an interesting tool for estimating organ burden.     

Risk factors for nosocomial rotavirus infection in a paediatric hospital: The potential role for rotavirus vaccine use

To analyze the incidence and risk factors (RF) of nosocomial infection (NI) in a paediatric teaching hospital, a retrospective cohort study was conducted in Salvador, Brazil. The Centres for Disease Control and Prevention definitions were used. The detection of the rotavirus antigen in stool was performed using a rapid latex agglutination test. The study group comprised 2978 admissions that accounted for 32,924 patient-days. The incidence of NI was 8.3/1000 patient-days and 9.2/100 admissions. Of the 274 NI episodes, the most common illness and causative agent were gastroenteritis (125; 45.6%) and rotavirus (59; 21.5%), respectively. The RF for rotavirus NI was young age (10 ± 8 months vs. 27 ± 33 months; mean difference 17 months, 95% CI 15–20 months, p < 0.001). The temporal distribution of community-acquired and NI rotavirus showed similar trends. The universal use of rotavirus vaccine is a potential tool to control NI among children.     

Long-term administration with levonorgestrel decreases allopregnanolone levels and alters GABA(A) receptor subunit expression and anxiety-like behavior

Fluctuations in the concentrations of the neuroactive steroid allopregnanolone are thought to influence γ-amino-butyric acid type A (GABA_A) receptor gene expression and function. Long-term treatment with ethinyl estradiol (EE) plus levonorgestrel (LNG), two of the most widely used steroids in the hormonal contraceptive pill, decreases allopregnanolone levels in rat cerebral cortex and plasma, alters GABA_A receptor expression and induces anxiety-like behavior. We evaluated which component of the hormonal contraceptive pill is responsible for the aforementioned changes. Female rats were injected subcutaneously (s.c.) with EE (0.030 mg) or LNG (0.125 mg) once a day for 4 weeks. Compared to the respective vehicle-treated control groups, EE decreased cerebral cortical levels of allopregnanolone, progesterone and pregnenolone by 76, 72 and 33%, respectively and hippocampal levels by 52, 56 and 50%, respectively. Likewise, LNG decreased cerebral cortical levels of allopregnanolone, progesterone and pregnenolone by 75, 68 and 33%, respectively, and hippocampal levels by 55, 65 and 60%, respectively. Administration of LNG, but not EE, increased the abundance of the γ2 subunit peptide in cerebral cortex and hippocampus by 38 and 59%, respectively. Further, LNG, but not EE, decreased the time spent and the number of entries into the open arms of the elevated plus maze by 56 and 43%, respectively, an index of anxiety-like behavior. These results suggest that alterations in GABA_A receptor subunit expression and anxiety-like behavior induced by long-term treatment with combined EE/LNG appear to be caused by LNG. Given that both EE and LNG decrease allopregnanolone levels in a similar manner, these results further suggest that changes in allopregnanolone levels are not associated with GABA_A receptor expression.     

An update on antimicrobial options for childhood community-acquired pneumonia: a critical appraisal of available evidence

Introduction: Community-acquired pneumonia (CAP) is a leading cause of death and a major cause of morbidity in children under the age of 5. Appropriate antimicrobial use is one crucial tool in controlling childhood CAP mortality and suffering.

Areas covered: Structured search of current literature. PubMed was consulted for published trials conducted in children with CAP. We aimed to provide a comprehensive evaluation of antimicrobials used to treat childhood CAP, including a critical appraisal of the methodological aspects of these clinical trials.

Expert opinion: Amoxicillin is the preferred option to treat non-severe non-complicated CAP among children aged ≥2 months. Amoxicillin may be used to treat children in this age group with severe CAP if they do not require hospital assistance. If the patient warrants hospitalization, intravenous penicillin is the chosen option. Heterogeneity was high in the included trials, in regard to clinical inclusion criteria, use of radiological inclusion criteria, placebo use and masking. Higher quality evidence was found in the studies which included amoxicillin. There is a clear dearth of randomized, placebo-controlled, well-performed clinical trials evaluating children with CAP aged under 2 months, or aged 2 months and above with very severe or complicated CAP, or in specific age groups like teenagers.     

Cost-effectiveness of maternal pertussis immunization: Implications of a dynamic transmission model for low- and middle-income countries

ObjectiveThis study evaluates the cost-effectiveness of maternal acellular pertussis (aP) immunization in low- and middle-income countries using a dynamic transmission model.MethodsWe developed a dynamic transmission model to simulate the impact of infant vaccination with whole-cell pertussis (wP) vaccine with and without maternal aP immunization. The model was calibrated to Brazilian surveillance data and then used to project health outcomes and costs under alternative strategies in Brazil, and, after adjusting model parameter values to reflect their conditions, in Nigeria and Bangladesh. The primary measure of cost-effectiveness is incremental cost (2014 USD) per disability-adjusted life-year (DALY).ResultsThe dynamic model shows that maternal aP immunization would be cost-effective in Brazil, a middle-income country, under the base-case assumptions, but would be very expensive at infant vaccination coverage in and above the threshold range necessary to eliminate the disease (90–95%). At 2007 infant coverage (DTP1 90%, DTP3 61% at 1 year of age), maternal immunization would cost < $4,000 per DALY averted. At high infant coverage, such as Brazil in 1996 (DTP1 94%, DTP3 74% at 1 year), cost/DALY increases to $1.27 million. When the model’s time horizon was extended from 2030 to 2100, cost/DALY increased under both infant coverage levels, but more steeply with high coverage. The results were moderately sensitive to discount rate, maternal vaccine price, and maternal aP coverage and were robust using the 100 best-fitting parameter sets. Scenarios representing low-income countries showed that maternal aP immunization could be cost-saving in countries with low infant coverage, such as Nigeria, but very expensive in countries, such as Bangladesh, with high infant coverage.ConclusionA dynamic model, which captures the herd immunity benefits of pertussis vaccination, shows that, in low- and middle-income countries, maternal aP immunization is cost-effective when infant vaccination coverage is moderate, even cost-saving when it is low, but not cost-effective when coverage levels pass 90–95%.     

Obesity and Circulating Levels of Vitamin D before and after Weight Loss Induced by a Very Low-Calorie Ketogenic Diet

Background: Vitamin D plays a pivotal role in calcium and phosphorus metabolism, also influencing bone tissue. Several studies have reported that vitamin D blood levels were significantly lower in people with obesity, probably due to its uptake by the adipose tissue. Clinical studies that investigated the changes of circulating levels of vitamin D following weight loss reported controversial data. A very low-calorie ketogenic diet is acknowledged as a reliable treatment to achieve a rapid weight loss. Therefore, we investigated the effect of weight loss, consequent to a very low-calorie ketogenic diet, on vitamin D blood concentrations. Methods: A cohort of 31 people with obesity underwent a very low-calorie ketogenic diet for 10–12 weeks. The serum concentrations of vitamin D, parathormone, calcium and phosphorous were measured before and after weight loss; they were compared to a control group of 20 non-obese, non-diabetic, age- and gender-matched persons. Results: Patients with obesity had a higher habitual intake of vitamin D than the control group (p < 0.05). However, the vitamin D blood levels of the obese group were significantly lower than those of the control group (p < 0.005) and they increased after weight loss (p < 0.001). At baseline, vitamin D blood concentrations of the persons with obesity were significantly correlated with both fat mass–kg (r = −0.40; p < 0.05) and body mass index (r = −0.47; p < 0.01). Following very low-calorie ketogenic diet, the change in vitamin D serum concentrations was correlated only with the change in fat mass–kg (r = −0.43; p < 0.01). Conclusion: This study confirmed that patients with obesity have lower vitamin D levels that normalize after significant weight loss, supporting the hypothesis that vitamin D is stored in the adipose tissue and released following weight loss.     

Influence of the surface coating on the cytotoxicity,genotoxicity and uptake of gold nanoparticles in human HepG2 cells

The toxicological profile of gold nanoparticles (AuNPs) remains controversial. Significant efforts to develop surface coatings to improve biocompatibility have been carried out. In vivo biodistribution studies have shown that the liver is a target for AuNPs accumulation. Therefore, we investigated the effects induced by ~20 nm spherical AuNPs (0–200 μM Au) with two surface coatings, citrate (Cit) compared with 11‐mercaptoundecanoic acid (11‐MUA), in human liver HepG2 cells. Cytotoxicity was evaluated using the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) reduction and lactate dehydrogenase (LDH) release assays after 24 to 72 h of incubation. DNA damage was assessed by the comet assay, 24 h after incubation with the capped AuNPs. Uptake and subcellular distribution of the tested AuNPs was evaluated by quantifying the gold intracellular content by graphite furnace atomic absorption spectrometry (GFAAS) and transmission electron microscopy (TEM), respectively. The obtained results indicate that both differently coated AuNPs did not induce significant cytotoxicity. An inverse concentration‐dependent increase in comet tail intensity and tail moment was observed in Cit‐AuNPs‐ but not in MUA‐AuNPs‐exposed cells. Both AuNPs were internalized in a concentration‐dependent manner. However, no differences were found in the extent of the internalization between the two types of NPs. Electron‐dense deposits of agglomerates of Cit‐ and MUA‐AuNPs were observed either inside endosomes or in the intercellular spaces. In spite of the absence of cytotoxicity, DNA damage was observed after exposure to the lower concentrations of Cit‐ but not to MUA‐AuNPs. Thus, our data supports the importance of the surface properties to increase the biocompatibility and safety of AuNPs. Copyright © 2013 John Wiley & Sons, Ltd.     

Comparison of α-tocopherol microparticles produced with different wall materials: pea protein a new interesting alternative

α-Tocopherol is a radical chain breaking antioxidant that can protect the integrity of tissues and play an important role in life process. Microparticles containing α-tocopherol were produced by spray drying technique using pea protein (PP), carboxymethylcellulose(CMC) and mixtures of these materials with maltodextrin (PP-M and CMC-M) as wall materials. The microparticles produced were characterised as regards the core retention (high performance liquid chromatography), the morphology (scanning electron microscopy) and size distribution (laser diffraction). The retention of α-tocopherol within all microparticles was above 77%. They showed a spherical shape and roughness at varied degrees. Their mean particles size remained below 7?µm, and the smallest sizes were found in PP and CMC-M microparticles. The results obtained in this work show that the pea protein use for α-tocopherol microencapsulation is a promising system for further application in food.     

Asthma-like symptoms assessment through ECRHS screening questionnaire scoring

The definition of asthma has always been a matter of discussion. The European Community Respiratory Health Survey (ECRHS) is a multinational survey designed to compare the prevalence of asthma in subjects aged 20 to 44 years throughout European countries. In each center a representative sample completed a self-administered screening questionnaire composed of nine dichotomous items. We propose a method for constructing a score for the ECRHS screening questionnaire and we validate the method with reference to the clinical diagnosis available for the Italian centers. Clinical diagnosis was made by a group of medical experts after examining the responses to a standardized clinical interview, respiratory function tests, and allergy tests. Before constructing a summary score, the number of latent factors/dimensions explaining correlations among the observed items was recognized. We identified only one factor/dimension underlying the screening questionnaire, so a summary score was determined by the Homogeneity Analysis by Alternating Least Square (HOMALS). Using best Receiver Operating Characteristic (ROC) threshold the diagnostic test of the score had sensitivity and specificity of 75.1 and 80.1%, respectively. The method of scoring is easily reproducible, and has the advantage of optimizing information recoded by the questionnaire.     

Relationship between repetitive work and the prevalence of carpal tunnel syndrome in part-time and full-time female supermarket cashiers: a <Emphasis Type="Italic">quasi</Emphasis>-experimental study

Objectives To investigate the prevalence of Carpal Tunnel Syndrome (CTS) in full-time and part-time supermarket cashiers exposed to a different weekly duration of biomechanical load. Methods All the 269 cashiers and 127 office workers were asked to participate. The protocol included ergonomic risk assessment, collection of personal and clinical data and bilateral electrodiagnostic study of the median nerve. CTS symptoms were defined as past and/or current nocturnal and/or diurnal numbness, tingling, burning or pain involving at least one of the first three fingers. Results were evaluated according to two case definitions based on current symptoms and on the combination of current symptoms and slowing of sensory conduction velocity from wrist to palm, respectively. Difference in proportions of CTS symptoms and cases was evaluated by the Pearson’s chi-square (χ²) test, univariate and multivariate logistic regression analyses were performed to determine the impact of weekly exposure. Results The final female study population included 71 full-time cashiers, 155 part-time cashiers and 98 office workers. Ergonomic risk level was rated 5 for hand activity level and 4 for peak of force according to ACGIH. The intersection of the two values fell on the threshold limit value line, confirming the possible exposure to biomechanical risk factors for CTS. The prevalence of current CTS symptoms was higher among full-time (31.0%) than in part-time cashiers (19.3%) or controls (16.3%) (p = 0.055). A similar pattern was found for CTS past symptoms and cases. Univariate analysis showed that full-time cashiers had a 2.3 fold increased risk for CTS specific current symptoms than control subjects. A similar trend also emerged for CTS cases but was not significant (Odds ratios 1.23). Multivariate logistic regression analysis confirmed the increased risk for CTS current symptoms in full-time cashiers. Conclusions Intensive manual work associated with inadequate recovery time might have generated an impairment of the median nerve at the wrist level proportionally increasing with duration of hand use. Our study can provide useful information both for ergonomic risk assessment and work organization.