Tubular ectasia of the rete testis associated with azoospermia: a case report

A research article on a rare form of benign condition of the testis due to dilatation of the tubules of the male reproductive organ.Tubular ectasia of the rete testis (TERT) is a rare benign condition of the testis due to dilatation of the tubules of the rete testis. It must be differentiated from neoplastic disease of the testis clinically by patient's age, mode of presentation, tumour marker status and characteristic Ultrasound and Colour Doppler findings.1 Awareness and diagnosis of TERT should prevent unnecessary surgical intervention such as orchidectomy or biopsy. We report a case of severe bilateral tubular ectasia of the rete testis associated with azoospermia and review the relevant literature. This association has not been reported before in the literature to the best of our knowledge

Treatment Effects and Integrated Morbidity Control of Schistosomiasis

Schistosomiasis is caused by the blood fl uke and leads to signifi cant ill-health and economic burden. The disease is common in the tropics and subtropics and acquired through contact with freshwater bodies infested with the infective cercariae shed from the intermediate host snail. From a public health perspective, the three most important species are Schistosoma mansoni and S. japonicum (causing intestinal schistosomiasis) and S. haematobium (causing urinary schistosomiasis). Schistosomiasis is endemic in 76 countries and territories worldwide (Engels et al. 2002; Steinmann et al. 2006) with around 85% of the infections confi ned to sub- Saharan Africa (Savioli et al. 1997; Chitsulo et al. 2000). Schistosomiasis is largely confi ned to rural dwellings and exacerbates poverty (Hotez et al. 2008; Wang et al. 2008). In some areas of sub-Saharan Africa there is an overlap in distribution of S. mansoni and S. haematobium resulting in mixed infections (WHO 2002). This thesis focuses on urinary schistosomiasis due to S. haematobium and intestinal schistosomiasis due to S. mansoni. Schistosomiasis is largely related to poverty, and efforts to alleviate poverty through development of water-related projects tend to increase transmission of the infection (Poda et al. 2004; Steinmann et al. 2006). Mostly children, women and farmers in poor rural areas who depend on water contact for recreational, domestic or occupational activities are affected. Peri-urban schistosomiasis is on the increase (Kloetzel et al. 1994; Chimbari & Chirundu 2003; Njiokou et al. 2004), and movement of displaced people from confl ict zones has contributed to the spread of the disease to previously non-endemic areas (Chitsulo et al. 2000)

Teaching mathematics in an inclusive basic school: A case study of the experiences of non-special education teachers

There is a general notion that the teaching and learning of mathematics to all students is quite a daunting task. However, there is a general perception that the move towards inclusive education [IE] may present unique challenges to regular teachers who teach mathematics in inclusive schools. In this study, we explored the experiences of a group of professionally-trained mathematics teachers who teach in a school designated as an inclusive school located in the southern part of Ghana. This was done with the aim of uncovering the challenges these teachers face considering that they do not have extended preparation in teaching students with special educational needs (SEN). An illustrative case study design was employed. Data was collected through the use of a semi-structured interview guide containing both closed-and-open-ended items. It was revealed that the participating teachers faced a number of challenges including inadequate knowledge and skills in teaching students with SEN. Another challenge unearthed has to do with assessing students who are blind due to difficulties faced by some of the teachers and students in using Braille to facilitate teaching and learning. The implications of the findings to teaching and learning are discussed

Investigation of yeast genes possibly involved in mtDNA stability using the nematode Caenorhabditis elegans

Screening of Caenorhabditis elegans genes possibly involved in the mitochondrial genome maintenance was performed using our previous validated method of RNAi combined with ethidium bromide. This was to knock down C. elegans genes homologous to yeast genes known to be involved in mtDNA stability but of unknown molecular function or to identify transient components that could play important role on the stability of mtDNA in a temporal and/or spatial manner. C. elegans homologs for 11 genes among 27 yeast genes for which deletion leads to a rho0 state were found, however, only 5 genes were present in the RNAi library. Out of these 5 genes, 1 gene (homolog of GEM1) gave a clear L3 arrest on RNAi and ethidium bromide indicating its involvement on mtDNA stability. Four other genes homologs of MTG2, YER087W, AVL9 and RRG3 did not lead to L3 arrest even though their deletion in Saccharomyces cerevisiae leads to rho0 state. Although MTG2 has been reported to be important in the function and structure on mtDNA stability in yeast, our results did not support those findings in C. elegans. The human homolog of this gene (MIRO1) can be considered as a candidate gene involved in mtDNA stability and sequenced in patients with mtDNA depletion diseases.Keywords: mtDNA, Caenorhabditis elegans, nucleoid, RNAi, candidate genes, homolog, MIRO

Anaerobic digestion of liquid products following hydrothermal carbonisation of faecal sludge at different reaction conditions

The hydrothermal carbonisation (HTC) conversion of wet wastes, such as sewage sludge, generates a carbon-rich material (called ‘hydrochar’), and an aqueous fraction with a small release of gas. The liquid fraction is high in soluble chemical oxygen demand, from 10 to 50 g/L, and could not be discharged to the natural environment without treatment. This study investigates the anaerobic digestibility of this HTC liquid stream from different HTC temperatures and retention times (140°C–200°C for 30–240 min). It is focused on biogas production in order to improve the energy input of the HTC process and to improve process sustainability. The results demonstrated that liquid products from the lower HTC temperatures gave better biogas production. The biogas yield from the 140°C HTC filtrate digestion was 0.45–0.86 L/L reactor/d, while 0.33 L/L reactor/d was obtained from 170°C and 0.31–0.45 L/L reactor/d from 180°C HTC filtrates. The lowest anaerobic digestion (AD) efficiency was recorded for the treatment from 200°C with biogas yield of 0.07 L/L reactor/d. The data also show that low AD hydraulic retention time (HRT), typical of high rate fixed biomass digesters can be used to treat the HTC filtrate. Halving the AD HRT to 0.9 d resulted in 1.8–6.8 times greater biogas yield

Restoration of degraded forest reserves in Ghana

Deforestation in Ghana has led to a forest loss of almost 20% from 9,924,000 ha in 1990 to 7,986,000 ha today. To restore degraded lands, Forest Landscape Restoration has become a critical approach globally. This study was conducted in Ghana focusing on the examples of two forest landscape restoration projects in the Pamu Berekum Forest Reserve: 10-year-old mixed-stands of two to four native tree species and an exotic species stands, including Triplochiton scleroxylon, Terminalia ivorensis, Ceiba pentandra, Nauclea diderrichii and Cedrela odorata at Pamu Berekum 1 and 4-year-old Tectona grandis and 2-year-old Gmelina arborea monoculture stands at Pamu Berekum 2. Estimates of productivity in the restored forests are described, as well as the effects of the restoration on provision of ecosystem service and benefits obtained by local communities. Stand productivity was assessed as mean annual increment of diameter and height, biomass production, and standing volume. For ecosystem services, carbon stocks were calculated for the restored forests; other ecological benefits, as well as financial benefits, were obtained through interviews with fringe communities. The results indicate that FLR can be implemented successfully using different models provided that local communities are involved during the planning and implementation of interventions. When all stands were projected to 10 years, results show higher productivity in T. grandis (331.77 m3 ha-1) and G. arborea stands (1,785.99 m3ha-1) compared to mixed stand (160.41 m3 ha-1). The Gmelina arborea stand was more productive and had higher carbon stocks (1,350.10 Mg ha-1) relative to the T. grandis stand (159.89 Mg ha-1). Both restoration projects were found to deliver important benefits and ecosystem services at the local and national levels, including direct and indirect benefits. The results provide an example for forest/environmental managers on how FLR might be implemented to create multiple benefits at different levels from local communities to the national level. Thus, these results may be useful for guiding successful restoration activities within the context of the ongoing global Forest Landscape Restoration efforts

Process energetics for the hydrothermal carbonisation of human faecal wastes

Hydrothermal carbonisation (HTC) has the capability to convert wet biomass such as sewage sludge to a lignite-like renewable solid fuel of high calorific value. However, to date assessment of the energy efficiency of the HTC process has not been fully investigated. In this work, mass and energy balances of semi-continuous HTC of faecal waste conducted at 200 °C and at a reaction time of 30 min are presented. This analysis is based on recovering steam from the process as well as energy from the solid fuel (hydrochar) and methane from digestion of the liquid product. The effect of the feedstock solids content and the quantity of feed on the mass and energy balance were investigated. The heat of reaction was measured at 200 °C for 4 h using wet faecal sludge, and the higher heating value was determined for the hydrochar. The results indicated that preheating the feed to 100 °C using heat recovered from the process would significantly reduce the energy input to the reactor by about 59%, and decreased the heat loss from the reactor by between 50% and 60%. For feedstocks containing 15–25% solids (for all feed rates), after the process is in operation, energy recycled from the flashing off of steam and combustion of the hydrochar and would be sufficient for preheating the feed, operating the reactor and drying the wet hydrochar without the need for any external sources of energy. Alternatively, for a feedstock containing 25% solids for all feed rates, energy recycled from the flashing off of steam and combustion of the methane provides sufficient energy to operate the entire process with an excess energy of about 19–21% which could be used for other purposes

Low-cost biomass as adsorbents for the removal of heavy metal ions from industrial wastewater used for crop irrigation in developing countries

Freshwater scarcity has prompted farmers in developing countries to rely on wastewater for agriculture. However, the concentrations of heavy metals in the wastewaters are found to be above the WHO/FAO recommended thresholds. This inherently presents concern particularly as it relates human health. Although, several conventional wastewater treatment technologies exist; their applications are limited by high procurement, operation and maintenance costs. Currently, studies on biomass wastes as low cost adsorbents are gaining momentum. In this study, coco-peat was considered for heavy metals removal. In this context, batch experiments were carried out in triplicates at 3 different contact times and pH. After 2hr of contact time at pH9, the coco-peat was proven to have Cr removal efficiency of 91.6% against 73.2% using an activated bone char; and 95.0% for Pb(II) against 91.2% for the bone char. This suggests that the use of coco-peat can provide cost effective means for metal removal from industrial wastewaters

Anemia Offers Stronger Protection Than Sickle Cell Trait Against the Erythrocytic Stage of Falciparum Malaria and This Protection Is Reversed by Iron Supplementation.

BACKGROUND: Iron deficiency causes long-term adverse consequences for children and is the most common nutritional deficiency worldwide. Observational studies suggest that iron deficiency anemia protects against Plasmodium falciparum malaria and several intervention trials have indicated that iron supplementation increases malaria risk through unknown mechanism(s). This poses a major challenge for health policy. We investigated how anemia inhibits blood stage malaria infection and how iron supplementation abrogates this protection. METHODS: This observational cohort study occurred in a malaria-endemic region where sickle-cell trait is also common. We studied fresh RBCs from anemic children (135 children; age 6-24months; hemoglobin <11g/dl) participating in an iron supplementation trial (ISRCTN registry, number ISRCTN07210906) in which they received iron (12mg/day) as part of a micronutrient powder for 84days. Children donated RBCs at baseline, Day 49, and Day 84 for use in flow cytometry-based in vitro growth and invasion assays with P. falciparum laboratory and field strains. In vitro parasite growth in subject RBCs was the primary endpoint. FINDINGS: Anemia substantially reduced the invasion and growth of both laboratory and field strains of P. falciparum in vitro (~10% growth reduction per standard deviation shift in hemoglobin). The population level impact against erythrocytic stage malaria was 15.9% from anemia compared to 3.5% for sickle-cell trait. Parasite growth was 2.4 fold higher after 49days of iron supplementation relative to baseline (p<0.001), paralleling increases in erythropoiesis. INTERPRETATION: These results confirm and quantify a plausible mechanism by which anemia protects African children against falciparum malaria, an effect that is substantially greater than the protection offered by sickle-cell trait. Iron supplementation completely reversed the observed protection and hence should be accompanied by malaria prophylaxis. Lower hemoglobin levels typically seen in populations of African descent may reflect past genetic selection by malaria. FUNDING: National Institute of Child Health and Development, Bill and Melinda Gates Foundation, UK Medical Research Council (MRC) and Department for International Development (DFID) under the MRC/DFID Concordat