Identification of embryonic lethal genes in humans by autozygosity mapping and exome sequencing in consanguineous families

BackgroundIdentifying genetic variants that lead to discernible phenotypes is the core of Mendelian genetics. An approach that considers embryonic lethality as a bona fide Mendelian phenotype has the potential to reveal novel genetic causes, which will further our understanding of early human development at a molecular level. Consanguineous families in which embryonic lethality segregates as a recessive Mendelian phenotype offer a unique opportunity for high throughput novel gene discovery as has been established for other recessive postnatal phenotypes.ResultsWe have studied 24 eligible families using autozygosity mapping and whole-exome sequencing. In addition to revealing mutations in genes previously linked to embryonic lethality in severe cases, our approach revealed seven novel candidate genes (THSD1, PIGC, UBN1, MYOM1, DNAH14, GALNT14, and FZD6). A founder mutation in one of these genes, THSD1, which has been linked to vascular permeability, accounted for embryonic lethality in three of the study families. Unlike the other six candidate genes, we were able to identify a second mutation in THSD1 in a family with a less severe phenotype consisting of hydrops fetalis and persistent postnatal edema, which provides further support for the proposed link between this gene and embryonic lethality.ConclusionsOur study represents an important step towards the systematic analysis of “embryonic lethal genes” in humans.

Electronic supplementary material

The online version of this article (doi:10.1186/s13059-015-0681-6) contains supplementary material, which is available to authorized users.     

Moringa peregrina leaf extracts produce anti-obesity,hypoglycemic, anti-hyperlipidemic,and hepatoprotective effects on high-fat diet fed rats

This present research investigated the anti-obesity and hepatoprotective effects of ethanolic Moringa peregrina leaf (MPLE) and bark extracts (MPBE), in the rats fed with a high-fat diet (HFD). Healthy male rats (n = 48) were randomly distributed to six groups (n = 8): control AIN-93 diet; HFD; HFD + MPBE bark extracts ((300 mg/kg); HFD + MPBE (600 mg/kg); HFD + MPLE (300 mg/kg); HFD + MPLE (600 mg/kg). HFD-fed rats in the Moringa peregrina (MP) treatment groups received orally administered MP leaf or bark extract daily for eight weeks. The results revealed that both doses of MP leaf extract significantly reduced HFD-induced increases in their food intake and the gained body weight, fat pad weights (visceral, subcutaneous, and epididymal), glucose and insulin plasma levels, and leptin and resistin serum levels in HFD-fed rats. Concomitantly, MP leaf extract improved glucose levels after oral or intraperitoneal glucose tolerance tests, reduced serum cholesterol, triglycerides, and the low-density lipoprotein LDL concentration, reduced hepatic triglycerides and cholesterol levels, and increased serum high-density lipoproteins HDL levels and triglycerides and cholesterol levels in fecal. Moreover, the administration of MPLE to HFD-fed rats improved liver architecture, reduced fat accumulation, reduced hepatic malondialdehyde, tumor necrosis factor-α, and interleukin-6 levels. Hepatic glutathione peroxidase, superoxide dismutase, and catalase activities were significantly increased. All observed effects were more pronounced in HFD-fed rats treated with a 600 mg/kg MP dose. However, neither dose of MPBE altered the measured markers in the HFD-fed rats. In conclusion, MPLE showed potential anti-obesity and hepatoprotective activity in HFD-induced obese rats, mediated by reduced lipid absorption, anti-hyperlipidemic effects, and hepatic antioxidant effects.     

Seasonal variation in nitrous oxide and methane emissions from subtropical estuary and coastal mangrove sediments, Australia

Mangrove sediments can act as sources of the greenhouse trace gases, nitrous oxide (N(2) O) and methane (CH(4) ). Confident reporting of trace gas emissions from mangrove sediments at local levels is important for regional emissions inventories, since small changes in N(2) O and CH(4) fluxes greatly influence greenhouse gas budgets due to their high global warming potentials. It is also important to identify the drivers of trace gas emission, to prioritize management for minimising emissions. We measured N(2) O and CH(4) fluxes and abiotic sediment parameters at midday low tide in winter and summer seasons, at four sites (27°33'S, 152°59'E) ranging from estuary to ocean sub-tropical mangrove sediments, having varied anthropogenic impacts. At all sites, sediment N(2) O and CH(4) emissions were significantly lower during winter (7-26 μg N(2) O m(-2) · h(-1); 47-466 μg CH(4) m(-2) · h(-1)) compared to summer (28-202 μg N(2) Om(-2) · h(-1); 247-1570 μg CH(4) m(-2) · h(-1)). Sediment temperature, ranging from 18 to 33°C, strongly influenced N(2) O and CH(4) emissions. Highest emissions (202 μg N(2) O m(-2) · h(-1), 1570 μg CH(4) m(-2) · h(-1) ) were detected at human-impacted estuary sites, which generally had higher total carbon (<8%) and total nitrogen (<0.4%) in sediments and reduced salinity (<16 dS · m(-1)). Large between-site variation highlights the need for regular monitoring of sub-tropical mangroves to capture short-lived, episodic N(2) O and CH(4) flux events that are affected by sediment biophysico-chemical conditions at site level. This is important, particularly at sites receiving anthropogenic nutrients, and that have variable freshwater inputs and tidal hydrology.     

Effects of Crude and Bioremediated Thermal Power Plant Effluents in Brassica Juncea

Crude phenol and cyanides are the major components of the effluents discharged by industries involved in the manufacture of many synthetic inorganic and organic compounds, pharmaceuticals, electroplating units, and thermal power plants.

In this study, an effort was made to use effluents as manure. The effect of various amendments (10, 40, 70, and 100%) of bioremediated and crude effluents was checked on plants of Brassica juncea. Roots, shoot lengths, and the mean dry weights were maximum in the plants irrigated with 10% treated and 10% crude effluent as compared to the control plants. Total plant phenolics increased with an increase in the amendment of the effluents in the plants irrigated with bioremediated as well as crude effluents. Applications of lower amendments of treated and untreated effluents in Brassica juncea improved the chlorophyll levels in the experimental plants and the values obtained were similar to the control plants. Effect of bioremediated and crude effluents on antioxidant enzymes of Brassica juncea showed a differential effect. The activity of antioxidant enzymes peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD) was observed to increase with an increase in the effluent concentration.

Here we demonstrate that the industrial effluents, when bioremediated of their harmful components, can also serve as a nourishment for plants, which can further help in the rehabilitation of wastelands.     

Provider-initiated HIV testing and counseling: increased uptake in two public community health centers in South Africa and implications for scale-up

Background

International guidance recommends the scale up of routinely recommended, offered, and delivered health care provider-initiated HIV testing and counseling (PITC) to increase the proportion of persons who know their HIV status. We compared HIV test uptake under PITC to provider-referral to voluntary counseling and testing (VCT referral) in two primary health centers in South Africa.

Methods

Prior to introducing PITC, clinical providers were instructed to refer systematically selected study participants to VCT. After PITC and HIV rapid test training, providers were asked to recommend, offer and provide HIV testing to study participants during the clinical consultation. Participants were interviewed before and after their consultation to assess their HIV testing experiences.

Results

HIV test uptake increased under PITC (OR 2.85, 95% CI 1.71, 4.76), and more patients felt providers answered their questions on HIV (104/141 [74%] versus 73/118 [62%] for VCT referral; p 0.04). After three months, only 4/106 (3.8%) HIV-positive patients had registered for onsite HIV treatment. Providers found PITC useful, but tested very few patients (range 0–15).

Conclusion

PITC increased the uptake of HIV testing compared with referral to onsite VCT, and patients reported a positive response to PITC. However, providing universal PITC will require strong leadership to train and motivate providers, and interventions to link HIV-positive persons to HIV treatment centers.     

Histological Changes in Kidney and Liver of Rats Due to Gold (III) Compound [Au(en)Cl2]Cl

Introduction

Development of novel metallodrugs with enhanced anti-proliferative potential and reduced toxicity has become the prime focus of the evolving medicinal chemistry. In this regards, gold (III) complexes with various ligands are being extensively investigated. In the current study renal and hepatic toxicity of a newly developed gold (III) compound [Au(en)Cl₂]Cl was assessed by histopathological evaluation of liver and kidney specimens of rats exposed to the compound.

Methods

Male rats (n = 42) weighing 200–250 gram were injected single, varying doses of gold (III) compound [(dichlorido(ethylenediamine)aurate((III)]chloride [Au(en)Cl₂]Cl in the acute toxicity component of the study. In the sub-acute toxicity part, a dose of 32.2 mg/kg (equivalent to 1/10 of LD50) was administered intraperitoneally for 14 consecutive days before sacrificing the animals. After autopsy, the renal and hepatic tissues were preserved in buffered formalin. Processing of the samples was followed by histopathological evaluation. The results were compared with the normal controls (n = 11).

Results

A dose of 32.2 mg/kg (1/10 of LD₅₀) revealed no renal tubular necrosis. The predominant histopathological finding was mild pyelitis, a prominence of eosinophils and mild congestion. The hepatic lesions comprised varying extents of ballooning degeneration with accompanying congestion and focal portal inflammation.

Conclusion

Gold (III) compound [Au(en)Cl₂]Cl causes minimal histological changes in kidney and liver of rats, reflecting its relative safety as compared to other clinically established antineoplastic drugs.     

Isoprostanes and isofurans as non-traditional risk factors for cardiovascular disease among Canadian Inuit

Abstract Objectives: The aim of the present study was to investigate the potential importance of oxidative stress, measured by isoprostanes-related compounds, as non-traditional risk factor for cardiovascular disease. We planned to examine the relationship between concentrations of plasma F(2)-isoprostanes (F(2)-IsoPs), isofurans (IsoFs), measures of obesity and various cardiometabolic risk factors. Materials and methods: Cross-sectional study using a sub-sample from the population of a survey conducted in the summer and fall 2007 and 2008 by Canadian Coastguard Ship Amundsen in 36 Canadian Arctic Inuit communities. Subjects included a subset (n =?233) of a total study population (n =?2595) with a mean age 42.56 ± 15.39 years and body mass index 27.78 ± 5.65 kg/m(2). Plasma levels of F(2)-IsoPs and IsoFs was determined by gas chromatography/negative ion chemical ionization/mass spectrometry (GC/NICI/MS) method; and their relationships to waist circumference (WC), blood pressure C reactive proteins (CRP), blood lipids and fasting glucose were assessed by multivariate analyses. Results: Plasma F(2)-IsoPs correlated positively with CRP (r =.132, P =.048) and systolic blood pressure (SBP) (r =.157, P =.024) after adjustment for age, sex and body mass index. IsoFs correlated with WC (r =.190, P =.005) and SBP (r =.137, P =.048). F2-IsoPs were not found elevated in smokers (P =.034), whereas IsoFs were decreased in smokers (P =.001). WC, SBP and sex were found to be major correlates of oxidative stress in Canadian Inuit. Conclusions: Plasma measures of F(2)-IsoPs and IsoFs increase with increased obesity and associated cardiometabolic risk factors, including CRP and blood pressure. Simultaneous measurement of IsoFs provides an advantageous mechanistic insight into oxidative stress not captured by F(2)-IsoPs alone.     

Interchangeability of Themis1 and Themis2 in thymocyte development reveals two related proteins with conserved molecular function

Themis1, a recently identified T cell protein, has a critical function in the generation of mature CD4(+)CD8(-) and CD4(-)CD8(+) (CD4 and CD8 single-positive [SP]) thymocytes and T cells. Although Themis1 has been shown to bind to the adaptor proteins LAT and Grb2, previous studies have yielded conflicting results regarding whether thymocytes from Themis1(-/-) mice exhibit TCR-mediated signaling defects. In this study, we demonstrate that, in the absence of Themis1, TCR-mediated signaling is selectively impaired in CD4 SP and CD8 SP thymocytes but is not affected in CD4(+)CD8(+) double-positive thymocytes despite high expression of Themis1 in double-positive thymocytes. Like Themis1, Themis2, a related member of the Themis family, which is expressed in B cells and macrophages, contains two conserved cysteine-based domains, a proline-rich region, and a nuclear localization signal. To determine whether Themis1 and Themis2 can perform similar functions in vivo, we analyzed T cell development and TCR-mediated signaling in Themis1(-/-) mice reconstituted with either Themis1 or Themis2 transgenes. Notably, Themis1 and Themis2 exhibited the same potential to restore T cell development and TCR-mediated signaling in Themis1(-/-) mice. Both proteins were tyrosine phosphorylated and were recruited within Grb2 signaling complexes to LAT following TCR engagement. These results suggest that conserved molecular features of the Themis1 and Themis2 proteins are important for their biological activity and predict that Themis1 and Themis2 may perform similar functions in T and B cells, respectively.