Repellent plants provide affordable natural screening to prevent mosquito house entry in tropical rural settings--results from a pilot efficacy study

Sustained malaria control is underway using a combination of vector control, prompt diagnosis and treatment of malaria cases. Progress is excellent, but for long-term control, low-cost, sustainable tools that supplement existing control programs are needed. Conventional vector control tools such as indoor residual spraying and house screening are highly effective, but difficult to deliver in rural areas. Therefore, an additional means of reducing mosquito house entry was evaluated: the screening of mosquito house entry points by planting the tall and densely foliated repellent plant Lantana camara L. around houses. A pilot efficacy study was performed in Kagera Region, Tanzania in an area of high seasonal malaria transmission, where consenting families within the study village planted L. camara (Lantana) around their homes and were responsible for maintaining the plants. Questionnaire data on house design, socioeconomic status, malaria prevention knowledge, attitude and practices was collected from 231 houses with Lantana planted around them 90 houses without repellent plants. Mosquitoes were collected using CDC Light Traps between September 2008 and July 2009. Data were analysed with generalised negative binomial regression, controlling for the effect of sampling period. Indoor catches of mosquitoes in houses with Lantana were compared using the Incidence Rate Ratio (IRR) relative to houses without plants in an adjusted analysis. There were 56% fewer Anopheles gambiae s.s. (IRR 0.44, 95% CI 0.28-0.68, p<0.0001); 83% fewer Anopheles funestus s.s. (IRR 0.17, 95% CI 0.09-0.32, p<0.0001), and 50% fewer mosquitoes of any kind (IRR 0.50, 95% CI 0.38-0.67, p<0.0001) in houses with Lantana relative to controls. House screening using Lantana reduced indoor densities of malaria vectors and nuisance mosquitoes with broad community acceptance. Providing sufficient plants for one home costs US $1.50 including maintenance and labour costs, (30 cents per person). L. camara mode of action and suitability for mosquito control is discussed.     

In vitro investigation of <Emphasis Type="Italic">Debaryomyces hansenii</Emphasis> strains for potential probiotic properties

In this study, 23 Debaryomyces hansenii strains, isolated from cheese and fish gut, were investigated in vitro for potential probiotic properties i.e. (1) survival under in vitro GI (gastrointestinal) conditions with different oxygen levels, (2) adhesion to Caco-2 intestinal epithelial cells and mucin, and (3) modulation of pro- and anti-inflammatory cytokine secretion by human monocyte-derived dendritic cells. As references two commercially available probiotic Saccharomyces cerevisiae var. boulardii (S. boulardii) strains were included in the study. Our results demonstrate that the different D. hansenii yeast strains had very diverse properties which could potentially lead to different probiotic effects. One strain of D. hansenii (DI 09) was capable of surviving GI stress conditions, although not to the same degree as the S. boulardii strains. This DI 09 strain, however, adhered more strongly to Caco-2 cells and mucin than the S. boulardii strains. Additionally, two D. hansenii strains (DI 10 and DI 15) elicited a higher IL-10/IL-12 ratio than the S. boulardii strains, indicating a higher anti-inflammatory effects on human dendritic cells. Finally, one strain of D. hansenii (DI 02) was evaluated as the best probiotic candidate because of its outstanding ability to survive the GI stresses, to adhere to Caco-2 cells and mucin and to induce a high IL-10/IL-12 ratio. In conclusion, this study shows that strains of D. hansenii may offer promising probiotic traits relevant for further study.     

Harvesting for food versus feed: a review of Peruvian fisheries in a global context

Peru is the top exporter of fishmeal and fish oil (FMFO) worldwide and is responsible for half and a third of global production, respectively. Landings of “anchoveta” (Engraulis ringens) are used nearly exclusively for FMFO production, despite a proactive national food policy aimed at favoring the direct human consumption of this inexpensive species. It may be surprising that in a country where malnutrition and caloric deficit constitute major issues, a low-priced and highly nutritious fish such as anchovy does not have stronger domestic demand as a food fish. Here, we review and assess eight potential politico-socio-economic processes that can explain this situation. The main explanation are dietary habits, the preference for broiler and the higher profit from anchovy sold as feed fish compared to its use as a food fish due to historically high FMFO prices, boosted by an increasing demand for aquaculture in a context of finite forage and trash fish resources. In addition, the recent introduction of an individual quota system has shifted bargaining power from processors to fishers, thereby increasing competition for the raw material. This competition results in an increase in anchovy prices offered by the feed fish industry due to its onshore processing overcapacity, which is detrimental to the food fish industry. In the end, although the dominant use of anchovy for fish feed is largely explained by integrating these market mechanisms and other minor ones, this use raises other issues, such as rent redistribution through public policies, employment, equitability and utility (low social costs), and resource management (threats to ecosystems or global change). Different policy scenarios are proposed in relation to these issues.     

The synergistic risk effect of apolipoprotein ε4 and DNA (cytosine-5-)-methyltransferase 3 beta (<Emphasis Type="Italic">DNMT3B</Emphasis>) haplotype for Alzheimer’s disease

Alzheimer’s disease (AD) is a complex and multifactorial disease with the contribution of several genes and polymorphisms to its development. Among these genes, the APOEε4 is the best known risk factor for AD. Methylation is associated with APOE expression and AD development. Recently, we found an association of the TGG haplotype in the DNMT3B gene, one of the catalyst enzyme for methylation, with AD. Therefore, the objective of the study was to investigate whether APOEε4 and TGG haplotype have an synergistic effect on AD. The sample was composed of 212 Caucasian individuals (108 healthy controls and 104 with AD by NINCDS-ADRDA and DSM-IV-TR criteria) from southern Brazil. The genetic analyses were performed by real time PCR for TaqMan^® assay. Multivariate logistic regression was performed categorizing groups according to presence of APOEε4 and/or TGG haplotype as an independent variable for outcome AD. The presence of TGG haplotype plus the allele APOEε4 were strongly associated with AD [OR 11.13; 95 % CI (4.25–29.16); P < 0.001]. This association had a higher risk than each risk factor alone. We found a strong association of the interaction of DNMT3B gene with the APOEε4 in this sample of AD patients. The presence of TGG haplotype and APOEε4 significantly increased the risk of developing the disease, showing an synergistic effect.     

Alveolar Gradient of Pentane in Normal Human Breath

Previous studies have raised the question of whether pentane is a normal constituent of human breath, since its concentrations in inspired room air and expired breath are often similar. Using a highly sensitive assay for volatile organic compounds, we studied 37 normal subjects in order to determine the alveolar gradient of pentane in their breath (i.e. concentration in alveolar breath minus concentration in the inspired air). The chemical identity of pentane was confirmed by mass spectroscopy. The alveolar gradient of pentane was zero ± 0.175 nmol/1 in 54.1 % of subjects, and distributed in an approximately bell-shaped curve. Determination of the alveolar gradient divided the normal subjects into three groups: the “passive equilibrators” who did not appear to excrete pentane in the breath (the majority), “metabolizers” who actively catabolized inhaled pentane, and “manufacturers” who excreted more pentane than they inhaled.     

Response to treatment in Brazilian patients with chronic hepatitis C is associated with a single-nucleotide polymorphism near the interleukin-28B gene

A single-nucleotide polymorphism (SNP) upstream of interleukin (IL)28B was recently identified as an important predictor of the outcome of chronic hepatitis C patients treated with pegylated interferon plus ribavirin (PEG-IFN/RBV). The aim of this study was to investigate the association between the IL28B gene polymorphism (rs12979860) and virological response in chronic hepatitis C patients. Brazilian patients (n = 263) who were infected with hepatitis C virus (HCV) genotype 1 and were receiving PEG-IFN/RBV were genotyped. Early virological response (EVR) (12 weeks), end-of-treatment response (EOTR) (48 weeks), sustained virological response (SVR) (72 weeks) and relapse were evaluated using conventional and quantitative polymerase chain reaction (PCR) assays. The frequency of the C allele in the population was 39%. Overall, 43% of patients experienced SVR. The IL28B CC genotype was significantly associated with higher treatment response rates and a lower relapse rate compared to the other genotypes [84% vs. 58% EVR, 92% vs. 63% EOTR, 76% vs. 38% SVR and 17% vs. 40% relapse rate in CC vs. other genotypes (CT and TT), respectively]. Thus, the IL28B genotype appears to be a strong predictor of SVR following PEG-IFN/RBV therapy in treatment-naïve Brazilian patients infected with HCV genotype 1. This study, together with similar research examining other SNPs, should help to define adequate protocols for the treatment of patients infected with HCV genotype 1, especially those with a poor prognosis.     

PPARA, RXRA, NR1I2 and NR1I3 gene polymorphisms and lipid and lipoprotein levels in a Southern Brazilian population

Cardiovascular disease is the main cause of death worldwide, and dyslipidemia is an important multifactorial risk factor. Considering the involvement of nuclear receptors in metabolic pathways, and that some of the receptors act in lipid metabolism and homeostasis, the aim of the present study was to investigate the influence of genetic variations in RXRA, PPARA, NR1I2, and NR1I3 on lipid and lipoprotein levels. Five polymorphisms in the aforementioned genes were genotyped in 622 Brazilians of European descent by PCR-RFLP or TaqMan genotyping assays. In general, carriers of the A insertion of RXRA rs11381416 polymorphism showed higher levels of triglyceride (TG; 1.80 ± 1.20 vs. 1.52 ± 1.20 mmol/L; P = 0.020). Moreover, sexual dimorphic association was found (gender*NR1I3 rs2501873 genotype interaction P < 0.001), males with NR1I3 rs2501873 G/G genotype had lower TG levels (ANCOVA, P = 0.009). Our results suggest that polymorphisms in the RXRA and NR1I3 genes influence lipid profile in a Southern Brazilian population. However, these general and gender association require confirmation in subsequent studies.     

In vitro culture supplementation of EGF for improving the survival of equine preantral follicles

Folliculogenesis is a process of development and maturation of the ovarian follicles, being essential for the maintenance of fertility. In in vivo conditions, 99.9% of the follicles of an ovary do not ovulate and undergo atresia. In order to minimize this loss and to clarify the existing mechanisms, a technique was developed that allows for the in vitro follicular development. The objective of this study was to evaluate the effects of different epidermal growth factor (EGF) concentrations on the in vitro culturing of equine preantral follicles. Ovaries (n?=?10) were collected from a local slaughterhouse of mares in seasonal anestrus, washed with 70% alcohol and PBS, and transported. The inner portion of the ovary was divided into 11 fragments of approximately 3?×?3?×?1 mm. A fragment of each ovary was immediately fixed in Bouin (control group). The remaining 10 fragments were individually cultured for 2 and 6 d. The medium was supplemented with different concentrations of EGF (0, 10, 50, 100, and 200 ng/mL). After cultivation, the fragments were processed and classified according to the developmental stage and morphology. In total, 1065 slides containing 6105 tissue sections were evaluated. Within 2 d of culture, there was a higher proportion of intact follicles at the EGF concentrations of 0 and 100 ng/mL (p?>?0.05). After 6 d of culture, only the EGF concentration of 100 ng/mL demonstrated a difference when compared to the other treatments (0, 10, 50 and 200 ng/mL of EGF, p?>?0.05). There was follicular development after 2 d at all EGF concentrations. Thus, we suggest that EGF promotes follicular survival in equines at a concentration of 100 ng/mL in in vitro cultures of ovarian fragments for 2 d. In addition, we suggest that EGF promotes follicular survival in equines at a concentration of 100 ng/mL in situ cultivation.     

The Rabl chromosome configuration masks a kinetochore reassembly mechanism in yeast mitosis

During cell cycle progression in metazoans, the kinetochore is assembled at mitotic onset and disassembled during mitotic exit. Once assembled, the kinetochore complex attached to centromeres interacts directly with the spindle microtubules, the vehicle of chromosome segregation. This reassembly program is assumed to be absent in budding and fission yeast, because most kinetochore proteins are stably maintained at the centromeres throughout the entire cell cycle. Here, we show that the reassembly program of the outer kinetochore at mitotic onset is unexpectedly conserved in the fission yeast Schizosaccharomyces pombe. We identified this behavior by removing the Rabl chromosome configuration, in which centromeres are permanently associated with the nuclear envelope beneath the spindle pole body during interphase. In addition to having evolutionary implications for kinetochore reassembly, our results aid the understanding of the molecular processes responsible for kinetochore disassembly and assembly during mitotic entry.