Cloning and Sequence Analysis of the Structural Gene for the bc 1 - Type Rieske Iron-Sulfur Protein from Thermus thermophilus HB8

The structural gene encoding the Rieske iron-sulfur protein from Thermus thermophilus HB8 has been cloned and sequenced. The gene encodes a protein of 209 amino acids that begins with a hydrophilic N-terminus followed by a stretch of 21 hydrophobic amino acids that could serve as a transmembrane helix. The remainder of the protein has a hydrophobicity pattern typical of a water-soluble protein. A phylogenetic analysis of 26 Rieske proteins that are part of bc 1 or b 6 f complexes shows that they fall into three major groups: eubacterial and mitochondrial, cyanobacterial and plastid, and five highly divergent outliers, including that of Thermus . Although the overall homology with other Rieske proteins is very low, the C-terminal half of the Thermus protein contains the signature sequence CTHLGC-(13X)-CPCH that most likely provides the ligands of the [2Fe-2S] cluster. It is proposed that this region of the protein represents a small domain that folds independently and that the encoding DNA sequence may have been transferred during evolution to several unrelated genes to provide the cluster attachment site to proteins of different origin. The role of individual residues in this domain of the Thermus protein is discussed vis-a-vis the three-dimensional structure of the bovine protein (Iwata et al ., 1996 Structure 4 , 567–579).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44801/1/10863_2004_Article_409077.pd

Sensory, microbiological and chemical changes in vacuum-packaged Blue Spotted Emperor (Lethrinus sp), Saddletail Snapper (Lutjanus malabaricus), Crimson Snapper (Lutjanus erythropterus), Barramundi (Lates calcarifer) and Atlantic Salmon (Salmo salar) fillets stored at 4°C

Quality assessment of finfish fillets during storage is important to be able to predict the shelf life of the fresh product during distribution. Microbial, chemical (pH, TMA, and TVB‐N), and sensory (Quality index assessment QIA, Torry scheme) changes in vacuum‐packaged blue‐spotted emperor (Lethrinus sp), saddletail (Lutjanus malabaricus), crimson snapper (Lutjanus erythropterus), barramundi (Lates calcarifer), and Atlantic salmon (Salmo salar) fillets stored at 4°C were evaluated for 5 days. Microbiological study included evaluation of TVC (total viable counts), total psychrotrophic organisms, and H2S‐producing bacteria. Numbers increased during storage time and reached an average of 8.5, 8.5, and 9.2 log10 cfu/g, respectively, for the five different fish species. These levels were above accepted microbiological limits for fish fillets. Although the sensory analyses showed a decrease in quality, none of the finfish fillets were considered unacceptable at the end of the storage trial. Chemically, there was a slight pH increase, but trimethylamine (TMA) levels remained low. However, total volatile basic nitrogen (TVB‐N) levels increased over time, reaching levels above 35 mg/100 g for blue spotted emperor, saddletail snapper, and crimson snapper by the end of the storage period. Results show that the deterioration of finfish fillet quality is a complex event of biochemical, sensory, and microbial factors, and multiple analyses may be required to define acceptability

Intestinal dysbiosis in preterm infants preceding necrotizing enterocolitis: a systematic review and meta-analysis

Background Necrotizing enterocolitis (NEC) is a catastrophic disease of preterm infants, and microbial dysbiosis has been implicated in its pathogenesis. Studies evaluating the microbiome in NEC and preterm infants lack power and have reported inconsistent results. Methods and results Our objectives were to perform a systematic review and meta-analyses of stool microbiome profiles in preterm infants to discern and describe microbial dysbiosis prior to the onset of NEC and to explore heterogeneity among studies. We searched MEDLINE, PubMed, CINAHL, and conference abstracts from the proceedings of Pediatric Academic Societies and reference lists of relevant identified articles in April 2016. Studies comparing the intestinal microbiome in preterm infants who developed NEC to those of controls, using culture-independent molecular techniques and reported α and β-diversity metrics, and microbial profiles were included. In addition, 16S ribosomal ribonucleic acid (rRNA) sequence data with clinical meta-data were requested from the authors of included studies or searched in public data repositories. We reprocessed the 16S rRNA sequence data through a uniform analysis pipeline, which were then synthesized by meta-analysis. We included 14 studies in this review, and data from eight studies were available for quantitative synthesis (106 NEC cases, 278 controls, 2944 samples). The age of NEC onset was at a mean ± SD of 30.1 ± 2.4 weeks post-conception (n = 61). Fecal microbiome from preterm infants with NEC had increased relative abundances of Proteobacteria and decreased relative abundances of Firmicutes and Bacteroidetes prior to NEC onset. Alpha- or beta-diversity indices in preterm infants with NEC were not consistently different from controls, but we found differences in taxonomic profiles related to antibiotic exposure, formula feeding, and mode of delivery. Exploring heterogeneity revealed differences in microbial profiles by study and the target region of the 16S rRNA gene (V1-V3 or V3-V5). Conclusions Microbial dysbiosis preceding NEC in preterm infants is characterized by increased relative abundances of Proteobacteria and decreased relative abundances of Firmicutes and Bacteroidetes. Microbiome optimization may provide a novel strategy for preventing NEC

AN ECOSYSTEM APPROACH TO FISHERIES IN THE SOUTHERN BENGUELA CONTEXT

The 2001 Reykjavík Declaration on Responsible Fisheries in the Marine Ecosystem and the Plan of Implementation of the 2002 World Summit on Sustainable Development highlighted the need in fisheries to look beyond considering only the target species and to consider in fisheries management the impacts of fishing on the ecosystem as a whole, as well as the impacts of the ecosystem on fisheries. This paper examines the practical implications of progressing towards ecosystem approaches by reference, in particular, to the FAO technical guidelines on the topic. It goes on to examine the major fishery types in South Africa and the southern Benguela, and to consider the probable impacts of those fisheries on target species, bycatch species and the ecosystem, as well as the indirect impacts on other ffected species. The review reveals that all fisheries have impacts beyond the target species and that an ecosystem approach is required in order to ensure the long-term sustainability of the living marine resources of the southern Benguela and the ecosystem as a whole. Finally, the likely obstacles to successful implementation of an ecosystem approach to fisheries in the southern Benguela are discussed.Afr. J. mar. Sci. 26: 9–3

A systematic review on the effects of group singing on persistent pain in people with long‐term health conditions

Singing can have a range of health benefits; this paper reviews the evidence of the effects of group singing for chronic pain in people with long‐term health conditions. We searched for published peer‐reviewed singing studies reporting pain measures (intensity, interference and depression) using major electronic databases (last search date 31 July 2018). After screening 123 full texts, 13 studies met the inclusion criteria: five randomized controlled trials (RCTs), seven non‐RCTs and one qualitative study. Included studies were appraised using Downs and Black and the Critical Appraisals Skills Programme quality assessments. Included studies reported differences in the type of singing intervention, long‐term condition and pain measures. Due to the high heterogeneity, we conducted a narrative review. Singing interventions were found to reduce pain intensity in most studies, but there was more equivocal support for reducing pain interference and depression. Additionally, qualitative data synthesis identified three key linked and complementary themes: physical, psychological and social benefits. Group singing appears to have the potential to reduce pain intensity, pain interference and depression; however, we conclude that there is only partial support for singing on some pain outcomes based on the limited available evidence of varied quality. Given the positive findings of qualitative studies, this review recommends that practitioners are encouraged to continue this work. More studies of better quality are needed. Future studies should adopt more robust methodology and report their singing intervention in details. Group singing may be an effective and safe approach for reducing persistent pain and depression in people with long‐term health conditions.Health and Social Care Research Centr

Hepatitis C virus cell-cell transmission and resistance to direct-acting antiviral agents

Hepatitis C virus (HCV) is transmitted between hepatocytes via classical cell entry but also uses direct cell-cell transfer to infect neighboring hepatocytes. Viral cell-cell transmission has been shown to play an important role in viral persistence allowing evasion from neutralizing antibodies. In contrast, the role of HCV cell-cell transmission for antiviral resistance is unknown. Aiming to address this question we investigated the phenotype of HCV strains exhibiting resistance to direct-acting antivirals (DAAs) in state-of-the-art model systems for cell-cell transmission and spread. Using HCV genotype 2 as a model virus, we show that cell-cell transmission is the main route of viral spread of DAA-resistant HCV. Cell-cell transmission of DAA-resistant viruses results in viral persistence and thus hampers viral eradication. We also show that blocking cell-cell transmission using host-targeting entry inhibitors (HTEIs) was highly effective in inhibiting viral dissemination of resistant genotype 2 viruses. Combining HTEIs with DAAs prevented antiviral resistance and led to rapid elimination of the virus in cell culture model. In conclusion, our work provides evidence that cell-cell transmission plays an important role in dissemination and maintenance of resistant variants in cell culture models. Blocking virus cell-cell transmission prevents emergence of drug resistance in persistent viral infection including resistance to HCV DAAs

Minimally invasive postmortem intestinal tissue sampling in malnourished and acutely ill children is feasible and informative

BACKGROUND: Intestinal disorders such as environmental enteric dysfunction (EED) are prevalent in low- and middle-income countries (LMICs) and important contributors to childhood undernutrition and mortality. Autopsies are rarely performed in LMICs but minimally invasive tissue sampling is increasingly deployed as a more feasible and acceptable procedure, although protocols have been devoid of intestinal sampling to date. We sought to determine (1) the feasibility of postmortem intestinal sampling, (2) whether autolysis precludes enteric biopsies\u27 utility, and (3) histopathologic features among children who died during hospitalization with acute illness or undernutrition. METHODS: Transabdominal needle and endoscopic forceps upper and lower intestinal sampling were conducted among children aged 1 week to 59 months who died while hospitalized in Blantyre, Malawi. Autolysis ratings were determined for each hematoxylin and eosin slide, and upper and lower intestinal scoring systems were adapted to assess histopathologic features and their severity. RESULTS: Endoscopic and transabdominal sampling procedures were attempted in 28 and 14 cases, respectively, with \u3e90% success obtaining targeted tissue. Varying degrees of autolysis were present in all samples and precluded histopathologic scoring of 6% of 122 biopsies. Greater autolysis in duodenal samples was seen with longer postmortem interval (Beta = 0.06, 95% confidence interval, 0.02-0.11). Histopathologic features identified included duodenal Paneth and goblet cell depletion. Acute inflammation was absent but chronic inflammation was prevalent in both upper and lower enteric samples. Severe chronic rectal inflammation was identified in children as young as 5.5 weeks. CONCLUSIONS: Minimally invasive postmortem intestinal sampling is feasible and identifies histopathology that can inform mortality contributors

Minimally invasive postmortem intestinal tissue sampling in malnourished and acutely ill children is feasible and informative

BACKGROUND: Intestinal disorders such as environmental enteric dysfunction (EED) are prevalent in low- and middle-income countries (LMICs) and important contributors to childhood undernutrition and mortality. Autopsies are rarely performed in LMICs but minimally invasive tissue sampling is increasingly deployed as a more feasible and acceptable procedure, although protocols have been devoid of intestinal sampling to date. We sought to determine (1) the feasibility of postmortem intestinal sampling, (2) whether autolysis precludes enteric biopsies\u27 utility, and (3) histopathologic features among children who died during hospitalization with acute illness or undernutrition. METHODS: Transabdominal needle and endoscopic forceps upper and lower intestinal sampling were conducted among children aged 1 week to 59 months who died while hospitalized in Blantyre, Malawi. Autolysis ratings were determined for each hematoxylin and eosin slide, and upper and lower intestinal scoring systems were adapted to assess histopathologic features and their severity. RESULTS: Endoscopic and transabdominal sampling procedures were attempted in 28 and 14 cases, respectively, with \u3e90% success obtaining targeted tissue. Varying degrees of autolysis were present in all samples and precluded histopathologic scoring of 6% of 122 biopsies. Greater autolysis in duodenal samples was seen with longer postmortem interval (Beta = 0.06, 95% confidence interval, 0.02-0.11). Histopathologic features identified included duodenal Paneth and goblet cell depletion. Acute inflammation was absent but chronic inflammation was prevalent in both upper and lower enteric samples. Severe chronic rectal inflammation was identified in children as young as 5.5 weeks. CONCLUSIONS: Minimally invasive postmortem intestinal sampling is feasible and identifies histopathology that can inform mortality contributors