Deciphering the Puzzle of Hypobaric Hypoxia Proteomics Prophylaxis and Modelling Approach

Hypoxia, particularly hypobaric hypoxia, is a multifaceted entity which includes certain molecular, patho-physiological and biochemical aspects. Any single aspect in itself cannot help us elucidate hypobaric hypoxia in its entirety. We observed three crucial lacunae within the existing literature. These include a lack of high-throughput investigations into redox PTMs, particularly NO-based PTMs; a prophylactic supplement with proven efficacy and safety which doesn’t involve medical supervision and is not contraindicated in hepatic, renal and cardiac insufficiencies; and a clinically validated rodent model of HAPE without any genetic/pharmacological manipulations. In the present study, we present an antagonistic interplay between nitrosylation and carbonylation which shows an additional NO-based network that is active in acclimatised individuals. Then we present a micronised aqueous suspension of silymarin which is efficacious at low doses in providing antioxidant, anti-inflammatory and hypoxia-adaptive vascular responses in addition to being a free radical quencher itself. Silymarin has an excellent safety and efficacy profile in humans. Finally, we create a SD rat model of HAPE which was used to reverse-translate a previously known HAPE marker in humans (SULT1A1) and elucidate the synergistic occurrence of HAPE and inflammation cascades. This is the first radiologically validated rodent HAPE model. In conclusion, we were able to elucidate the molecular, biochemical and patho-physiological aspects of hypobaric hypoxia which were left out by previous studies

Bacterial pathogens in wound infection and their antimicrobial susceptibility pattern in a medical college hospital, in Dhaka, Bangladesh

Background: Wound infection is a major health problem that results in prolong hospital stay, increased treatment cost and are responsible for significant mortality and morbidity worldwide. The aim of the present study was to isolate and identify the bacterial pathogens causing wound infection and to determine their antimicrobial susceptibility profile.Methods: This cross sectional study was conducted at the Department of Microbiology, Sir Salimullah Medical College, Dhaka from January 2016 to December 2016. Wound swab samples were collected and inoculated into appropriate media. The bacterial pathogens were identified by using standard microbiological methods. Antimicrobial susceptibility test were performed using disc diffusion technique following Kirby-Bauer method.Results: Out of 239 wound swab samples analyzed 173 (72.4%) were culture positive. Majority (35.3%) of culture positive cases were in age group 16-30 years and 60.1% were male. Staphylococcus aureus (36.9%) was the predominant isolate, followed by Escherichia coli (35.8%), Pseudomonas spp. (17.3%) and Proteus spp. (5.8%). Bacterial isolates were highly resistant Amoxicillin (89-100%), Cephalosporin (60-100%), Ciprofloxacin (53-71%), while they were least resistant to Imipenem (0-14%) and Amikacin (17-30%).  Conclusions: In the present study most of the isolates showed high rate of resistance to commonly used antibiotics. Therefore regular monitoring and rational use of antibiotic should be practiced

MOLECULAR CHARACTERIZATION OF ENTEROPATHOGENIC E. COLI (EPEC) AND SHIGA-TOXIN PRODUCING E. COLI (STEC) FROM DOMESTIC ANIMALS: PREVALENCE, VIRULENCE, COLONIZATION FACTORS AND THEIR ANTIMICROBIAL RESISTANCE

To ascertain the presence and molecular characterization of enteropathogenic and Shiga toxin E. coli, 200 fecal samples were collected from rabbits (24), slaughtered pigs (22), calves (39), poultry (41), dogs (38), sheep and goats (36). All the 200 isolates were screened using m-PCR for the presence of the eae, stx1, and stx2 genes. Additionally, the confirmed EPEC isolates were screened concerning their virulence factors (bfpA, astA and ecpA genes) and serogroup by PCR and antibiotic resistance. Of the 200 samples, 38 (19.00%) and 28 (14.0%) were found to be STEC and EPEC, respectively. It was discovered that 11 (30.55%), 12 (33.33%) isolates from sheep and 17 (43.58%), 5 (12.82%), isolates from calves, respectively, were STEC and EPEC 6 (25.0%), 10 (45.45%), and 5 (13.15%) isolates were found to be EPEC in rabbits, pigs, and dogs, respectively. The two most common EPEC serogroups were O118 (18.41%) and O88 (36.84%). Of the 38 EPEC isolates, 100% carried the ecpA gene, while 18 isolates (47.36%) took the astA gene. Among 38 EPEC isolates, only 5 (13.15%) dogs were found to have the bfpA gene, making them typical EPEC, while 33 (86.84%) isolates were classified as atypical EPEC. Thirtyeight EPEC isolates were tested for antibiotic sensitivity, and the results indicated that they were resistant to ciprofloxacin (13.15%), kanamycin (42.10%), streptomycin (42.10%), doxycycline hydrochloride (28.94%), and nalidixic acid (55.26%)

Acute Consumption of Flavan-3-ol-Enriched Dark Chocolate Affects Human Endogenous Metabolism

Flavan-3-ols and methylxanthines have potential beneficial effects on human health including reducing cardiovascular risk. We performed a randomized controlled crossover intervention trial to assess the acute effects of consumption of flavan-3-ol-enriched dark chocolate, compared with standard dark chocolate and white chocolate, on the human metabolome. We assessed the metabolome in urine and blood plasma samples collected before and at 2 and 6 h after consumption of chocolates in 42 healthy volunteers using a nontargeted metabolomics approach. Plasma samples were assessed and showed differentiation between time points with no further separation among the three chocolate treatments. Multivariate statistics applied to urine samples could readily separate the postprandial time points and distinguish between the treatments. Most of the markers responsible for the multivariate discrimination between the chocolates were of dietary origin. Interestingly, small but significant level changes were also observed for a subset of endogenous metabolites. H-1 NMR revealed that flavan-3-ol-enriched dark chocolate and standard dark chocolate reduced urinary levels of creatinine, lactate, some amino acids, and related degradation products and increased the levels of pyruvate and 4-hydroxyphenylacetate, a phenolic compound of bacterial origin. This study demonstrates that an acute chocolate intervention can significantly affect human metabolism

Comparative bio-accessibility, bioavailability and bioequivalence of quercetin, apigenin, glucoraphanin and carotenoids from freeze-dried vegetables incorporated into a baked snack versus minimally processed vegetables:Evidence from in vitro models and a human bioavailability study

The aim was to incorporate vegetables containing the phytochemicals quercetin, apigenin, glucoraphanin and carotenoids into a processed potato-based snack and assess their bioaccessibility and bioavailability. Three different processing routes were tested for incorporation and retention of phytochemicals in snacks using individually quick frozen or freeze-dried vegetables. No significant differences in the uptake or transport of quercetin or apigenin between a vegetable mix or snacks were observed using the CaCo-2 transwell model. Simulated in vitro digestions predicted a substantial release of quercetin and apigenin, some release of glucoraphanin but none for carotenes from either the snack or equivalent steamed vegetables. In humans, there were no significant differences in the bioavailability of quercetin, apigenin or glucoraphanin from the snack or equivalent steamed vegetables. We have shown that significant quantities of freeze-dried vegetables can be incorporated into snacks with good retention of phytochemicals and with similar bioavailability to equivalent steamed vegetables

Accumulation of Dietary S-Methyl Cysteine Sulfoxide in Human Prostate Tissue

Scope: Observational studies have associated consumption of cruciferous vegetables with reduced risk of prostate cancer. This effect has been associated with the degradation products of glucosinolates—thioglycosides that accumulate within crucifers. The possible role of S-methyl cysteine sulfoxide, a metabolite that also accumulates in cruciferous vegetables, and its derivatives, in cancer prevention is relatively unexplored compared to glucosinolate derivatives. The hypothesis that consuming a broccoli soup results in the accumulation of sulfate (a SMCSO derivative) and other broccoli-derived metabolites in prostate tissue is tested. Methods and results: Eighteen men scheduled for transperineal prostate biopsy were recruited into a 4-week parallel single blinded diet supplementation study (NCT02821728). Nine men supplemented their diet with three 300 mL portions of a broccoli soup each week for four weeks prior to surgery. Analyses of prostate biopsy tissues reveal no detectable levels of glucosinolates and derivatives. In contrast, SMCSO is detected in prostate tissues of the participants, with significantly higher levels in tissue of men in the supplementation arm. SMCSO was also found in blood and urine samples from a previous intervention study with the identical broccoli soup. Conclusion: The consequences of SMCSO accumulation in prostate tissues and its potential role in prevention of prostate cancer remains to be investigated

Nitrification and urease inhibitors reduce gaseous N losses and improve nitrogen use efficiency in wheat exposed to elevated CO2 and temperature

•Introduction: Climate change significantly impacts food production by influencing crop growth and soil processes. Rising atmospheric CO2 levels and temperatures may affect reactive nitrogen losses from cultivated soils. This study aimed to quantify the effects of nitrification and urease inhibitors on reactive nitrogen losses from wheat soils in the context of elevated CO2 and temperature interactions. •Methods: An experiment was conducted in open top chambers for two consecutive years to quantify the effect of nitrification and urease inhibitors on ammonia (NH3), and nitrous oxide (N2O) emissions in wheat under elevated carbon dioxide (EC), elevated temperature (ET) and their interaction (ECT). The carbon dioxide (CO2) concentration ranged from 552 to 568 ppm in the EC treatment, while the average temperature was 2.1–2.5°C higher in ET treatment than ambient (AMB). •Results and discussion: The N2O–N emission increased under ECT than ambient. Use of neem oil coated urea (NOCU) reduced the N2O–N emission by 10.3%, whereas, Limus coated urea reduced N2O–N emission by 14% as compared to prilled urea treatment under ECT. NH3–N emission from wheat soil also increased under ECT treatment as compared to AMB. Application of N through Limus, reduced NH3–N emission from wheat by 35.7–36.8% when compared with NH3–N emission from prilled urea ECT condition. Elevated temperature reduced grain weight by 7.6%. The grain N content reduced by 10.9% with prilled urea under ECT. The application of NOCU and Limus increased grain N by 6 and 9%, respectively, as compared to urea under ECT interaction. The application of nitrification and urease inhibitors may reduce reactive nitrogen losses and enhance nitrogen use efficiency under future climatic conditions

The use of an in-vitro batch fermentation (human colon) model for investigating mechanisms of TMA production from choline, L-carnitine and related precursors by the human gut microbiota

Purpose: Plasma trimethylamine-N-oxide (TMAO) levels have been shown to correlate with increased risk of metabolic diseases including cardiovascular diseases. TMAO exposure predominantly occurs as a consequence of gut microbiota-dependent trimethylamine (TMA) production from dietary substrates including choline, carnitine and betaine, which is then converted to TMAO in the liver. Reducing microbial TMA production is likely to be the most effective and sustainable approach to overcoming TMAO burden in humans. Current models for studying microbial TMA production have numerous weaknesses including the cost and length of human studies, differences in TMA(O) metabolism in animal models and the risk of failing to replicate multi-enzyme/multi-strain pathways when using isolated bacterial strains. The purpose of this research was to investigate TMA production from dietary precursors in an in-vitro model of the human colon. Methods: TMA production from choline, l-carnitine, betaine and γ-butyrobetaine was studied over 24–48 h using an in-vitro human colon model with metabolite quantification performed using LC–MS. Results: Choline was metabolised via the direct choline TMA-lyase route but not the indirect choline–betaine-TMA route, conversion of l-carnitine to TMA was slower than that of choline and involves the formation of the intermediate γ-BB, whereas the Rieske-type monooxygenase/reductase pathway for l-carnitine metabolism to TMA was negligible. The rate of TMA production from precursors was choline > carnitine > betaine > γ-BB. 3,3-Dimethyl-1-butanol (DMB) had no effect on the conversion of choline to TMA. Conclusion: The metabolic routes for microbial TMA production in the colon model are consistent with observations from human studies. Thus, this model is suitable for studying gut microbiota metabolism of TMA and for screening potential therapeutic targets that aim to attenuate TMA production by the gut microbiota. Trial registration number: NCT02653001 (http://www.clinicaltrials.gov), registered 12 Jan 2016

Transcriptional changes in prostate of men on active surveillance after a 12-mo glucoraphanin-rich broccoli intervention—results from the Effect of Sulforaphane on prostate CAncer PrEvention (ESCAPE) randomized controlled trial

Background Epidemiological evidence suggests that consumption of cruciferous vegetables is associated with reduced risk of prostate cancer progression, largely attributed to the biological activity of glucosinolate degradation products, such as sulforaphane derived from glucoraphanin. Because there are few therapeutic interventions for men on active surveillance for prostate cancer to reduce the risk of cancer progression, dietary approaches are an appealing option for patients. Objective We evaluated whether consumption of a glucoraphanin-rich broccoli soup for 1 y leads to changes in gene expression in prostate tissue of men with localized prostate cancer. Methods Forty-nine men on active surveillance completed a 3-arm parallel randomized double-blinded intervention study for 12 mo and underwent transperineal template biopsy procedures and dietary assessment at the start and end of the study. Patients received a weekly 300 mL portion of soup made from a standard broccoli (control) or from 1 of 2 experimental broccoli genotypes with enhanced concentrations of glucoraphanin, delivering 3 and 7 times that of the control, respectively. Gene expression in tissues from each patient obtained before and after the dietary intervention was quantified by RNA sequencing followed by gene set enrichment analyses. Results In the control arm, there were several hundred changes in gene expression in nonneoplastic tissue during the 12 mo. These were associated with an increase in expression of potentially oncogenic pathways including inflammation processes and epithelial–mesenchymal transition. Changes in gene expression and associated oncogenic pathways were attenuated in men on the glucoraphanin-rich broccoli soup in a dose-dependent manner. Although the study was not powered to assess clinical progression, an inverse association between consumption of cruciferous vegetables and cancer progression was observed. Conclusion Consuming glucoraphanin-rich broccoli soup affected gene expression in the prostate of men on active surveillance, consistent with a reduction in the risk of cancer progression. This trial was registered at clinicaltrials.gov as NCT01950143