Arginine deiminase pathway provides ATP and boosts growth of the gas-fermenting acetogen Clostridium autoethanogenum.

Acetogens are attractive organisms for the production of chemicals and fuels from inexpensive and non-food feedstocks such as syngas (CO, CO2 and H2). Expanding their product spectrum beyond native compounds is dictated by energetics, particularly ATP availability. Acetogens have evolved sophisticated strategies to conserve energy from reduction potential differences between major redox couples, however, this coupling is sensitive to small changes in thermodynamic equilibria. To accelerate the development of strains for energy-intensive products from gases, we used a genome-scale metabolic model (GEM) to explore alternative ATP-generating pathways in the gas-fermenting acetogen Clostridium autoethanogenum. Shadow price analysis revealed a preference of C. autoethanogenum for nine amino acids. This prediction was experimentally confirmed under heterotrophic conditions. Subsequent in silico simulations identified arginine (ARG) as a key enhancer for growth. Predictions were experimentally validated, and faster growth was measured in media containing ARG (tD~4h) compared to growth on yeast extract (tD~9h). The growth-boosting effect of ARG was confirmed during autotrophic growth. Metabolic modelling and experiments showed that acetate production is nearly abolished and fast growth is realised by a three-fold increase in ATP production through the arginine deiminase (ADI) pathway. The involvement of the ADI pathway was confirmed by metabolomics and RNA-sequencing which revealed a ~500-fold up-regulation of the ADI pathway with an unexpected down-regulation of the Wood-Ljungdahl pathway. The data presented here offer a potential route for supplying cells with ATP, while demonstrating the usefulness of metabolic modelling for the discovery of native pathways for stimulating growth or enhancing energy availability.

Exercise Training on Anginal Threshold Does Not Improve Endothelial Function in Refractory Angina Patients.

Refractory angina (RA) is a chronic condition of coronary artery disease (CAD). Endothelial function (EF) measured by flow-mediated dilation (FMD) is an important prognostic marker in CAD. Exercise training is a stimulus that improves EF in CAD. However, exercise training effects on EF in RA are unknown. Therefore, we aimed to verify the effects of exercise training on EF in RA. This was a longitudinal, non-randomized clinical study, involving patients with patients limited by angina, aged 45 to 75 years. Patients were prospectively allocated by convenience to either exercise trained (ET) or control group (C). Laboratory analysis, cardiopulmonary exercise test (CPET), and FMD were implemented at inclusion and after 12 weeks of exercise training or clinical treatment period. Exercise training included 60 minutes per session, 3 times a week, including 40 minutes of aerobic exercise on anginal threshold heart rate obtained on the CPET, 15 minutes of resistance training, and 5 minutes of stretching. A total of 38 patients were included (mean age 60 ± 9 years, 22 men); 21 were allocated to the ET and 17 to the C group. Baseline measures showed no differences between groups. After 12 weeks glycated hemoglobin and systolic blood pressure were lower in ET before than ET after (p = 0.004, and p = 0.05, respectively), and exercise time of the CPET was lower in ET before than ET after (p = 0.002). Exercise training did not change FMD. In conclusion, exercise training performed on anginal threshold increases exercise tolerance but causes no changes in EF in patients with RA.

Cardiopulmonary exercise test in patients with refractory angina: functional and ischemic evaluation.

OBJECTIVES: Refractory angina (RA) is a chronic condition clinically characterized by low effort tolerance; therefore, physical stress testing is not usually requested for these patients. Cardiopulmonary exercise testing (CPET) is considered a gold standard examination for functional capacity evaluation, even in submaximal tests, and it has gained great prominence in detecting ischemia. The authors aimed to determine cardiorespiratory capacity by using the oxygen consumption efficiency slope (OUES) in patients with refractory angina. The authors also studied the O2 pulse response by CPET and the association of ischemic changes with contractile modifications by exercise stress echocardiography (ESE). METHODS: Thirty-one patients of both sexes, aged 45 to 75 years, with symptomatic (Canadian Cardiovascular Society class II to IV) angina who underwent CPET on a treadmill and exercise stress echocardiography on a lower limb cycle ergometer were studied. ClinicalTrials.gov: NCT03218891. RESULTS: The patients had low cardiorespiratory capacity (OUES of 1.74 ± 0.4 L/min; 63.9±14.7% of predicted), and 77% of patients had a flattening or drop in O2 pulse response. There was a direct association between Heart Rate (HR) at the onset of myocardial ischemia detected by ESE and HR at the onset of flattening or drop in oxygen pulse response detected by CPET (R = 0.48; p = 0.019). CONCLUSION: Patients with refractory angina demonstrate low cardiorespiratory capacity. CPET shows good sensitivity for detecting abnormal cardiovascular response in these patients with a significant relationship between flattening O2 pulse response during CEPT and contractile alterations detected by exercise stress echocardiography.

Sensorial analysis of expressed human milk and its microbial load.

OBJECTIVE: To verify the existence of a relationship between presence of off-flavor and microorganism load in quality control rejected samples of expressed human milk from a donor milk bank. METHODS: A total of 30 samples of expressed human milk with off-flavor were tested for the occurrence of the following microorganisms: aerobic mesophilic, psycrotrophic, proteolytic, psycrotrophic proteolytic, thermoduric, psycrotrophic thermoduric, lactate and lipolytic bacteria, molds and yeasts and Staphylococcus aureus, total coliforms and thermophilic coliforms, in accordance with official methods. RESULTS: Percentage occurrence of microorganisms was as follows: aerobic mesophilic = 80%; psycrotrophic = 36.7%; proteolytic = 46.7%; psycrotrophic proteolytic = 16.7%; thermoduric = 6.7%; psycrotrophic thermoduric = 0%; lactate bacteria = 50%; lipolytic = 10%; molds and yeasts = 6.7%; S. aureus = 30%; total coliforms = 53.3%; and thermophilic coliforms = 16.7%. CONCLUSION: A consistent relationship between presence of off-flavor and elevated microorganism counting was observed in the analyzed samples. This correlation highlights the importance of off-flavor research during selection and quality control processes in human milk banks.

Cardiopulmonary exercise test in patients with refractory angina: functional and ischemic evaluation

Abstract Objectives Refractory angina (RA) is a chronic condition clinically characterized by low effort tolerance; therefore, physical stress testing is not usually requested for these patients. Cardiopulmonary exercise testing (CPET) is considered a gold standard examination for functional capacity evaluation, even in submaximal tests, and it has gained great prominence in detecting ischemia. The authors aimed to determine cardiorespiratory capacity by using the oxygen consumption efficiency slope (OUES) in patients with refractory angina. The authors also studied the O2 pulse response by CPET and the association of ischemic changes with contractile modifications by exercise stress echocardiography (ESE). Methods Thirty-one patients of both sexes, aged 45 to 75 years, with symptomatic (Canadian Cardiovascular Society class II to IV) angina who underwent CPET on a treadmill and exercise stress echocardiography on a lower limb cycle ergometer were studied. ClinicalTrials.gov: NCT03218891. Results The patients had low cardiorespiratory capacity (OUES of 1.74 ± 0.4 L/min; 63.9±14.7% of predicted), and 77% of patients had a flattening or drop in O2 pulse response. There was a direct association between Heart Rate (HR) at the onset of myocardial ischemia detected by ESE and HR at the onset of flattening or drop in oxygen pulse response detected by CPET (R = 0.48; p = 0.019). Conclusion Patients with refractory angina demonstrate low cardiorespiratory capacity. CPET shows good sensitivity for detecting abnormal cardiovascular response in these patients with a significant relationship between flattening O2 pulse response during CEPT and contractile alterations detected by exercise stress echocardiography. Highlights OUES analysis is useful for assessing functional capacity in refractory angina. O2 pulse curve is correlated with contractile alterations in exercise echocardiogram. Cardiopulmonary exercise test is useful toll in patients with refractory angina.

Smoking status and its relationship with exercise capacity, physical activity in daily life and quality of life in physically independent, elderly individuals.

OBJECTIVE: To investigate the relationship between smoking status and exercise capacity, physical activity in daily life and health-related quality of life in physically independent, elderly (≥60 years) individuals. DESIGN: Cross-sectional, observational study. SETTING: Community-dwelling, elderly individuals. PARTICIPANTS: One hundred and fifty-four elderly individuals were categorised into four groups according to their smoking status: never smokers (n=57), passive smokers (n=30), ex-smokers (n=45) and current smokers (n=22). MAIN OUTCOME MEASURES: Exercise capacity [6-minute walk test (6MWT)], physical activity in daily life (step counting) and health-related quality of life [36-Item Short Form Health Survey (SF-36) questionnaire] were assessed. RESULTS: Current and ex-smokers had lower mean exercise capacity compared with never smokers: 90 [standard deviation (SD) 10] % predicted, 91 (SD 12) % predicted and 100 (SD 13) % predicted distance on 6MWT, respectively [mean differences -9.8%, 95% confidence intervals (CI) -17.8 to -1.8 and -9.1%, 95% CI -15.4 to -2.7, respectively; P<0.05 for both]. The level of physical activity did not differ between the groups, but was found to correlate negatively with the level of nicotine dependence in current smokers (r=-0.47, P=0.03). The median score for the mental health dimension of SF-36 was worse in passive {72 [interquartile range (IQR) 56 to 96] points} and current [76 (IQR 55 to 80) points] smokers compared with ex-smokers [88 (IQR 70 to 100) points] (median differences -16 points, 95% CI -22.2 to -3.0 and -12 points, 95% CI -22.8 to -2.4, respectively; P<0.05 for both). CONCLUSIONS: Among elderly individuals, current smokers had lower exercise capacity than never smokers. Although the level of physical activity did not differ between the groups, an association was found with smoking. Tobacco exposure was associated with worse scores for the mental health dimension of SF-36 in physically independent, elderly individuals.

Occurrence and significance of Cryptosporidium infection in Calcutta.

During a 2-year study, Cryptosporidium oocysts were detected in 32 (5.6%) of 566 hospitalized paediatric diarrhoea cases and 2 (1.2%) of 167 non-diarrhoeic individuals. Cryptosporidium was the sole pathogen detected in 17 (3.0%) of the 32 positive cases; in the other 15 it occurred in combination with one or more other established enteropathogen(s). The frequency of detection of the parasite was highest in the 0-6 months age group; no sex-specific difference was discernible. The detection rate of the parasite was highest during the monsoon and post-monsoon months. Most of the patients had watery stools with a mild to moderate degree of dehydration, with the diarrhoea lasting for less than 7 d.

Aetiological studies on hospital in-patients with acute diarrhoea in Calcutta.

Bacterial enteropathogens and rotavirus were sought in 356 cases with acute diarrhoea admitted to the Infectious Diseases Hospital, Calcutta. One or more pathogens were isolated from 74.7% of the cases. Single enteropathogens could be detected from 66% and multiple enteropathogens from 8.7% of the patients. Vibrio cholerae biotype El Tor, rotavirus, V. parahaemolyticus, and enteropathogenic and enterotoxigenic Escherichia coli were the major pathogens detected. Rotavirus was detected from 7.6% of the cases. A higher rate of detection of rotavirus was seen in children younger than two years. Campylobacter jejuni could be isolated from the faeces of six (15%) of 40 cases either as a single pathogen or in association with V. cholerae biotype El Tor.

Kanagawa phenomenon and serotypic pattern of Vibrio parahaemolyticus strains isolated from various sources in Calcutta.

A total of 135 strains of Vibrio parahaemolyticus isolated during the period 1976-77 from human gastroenteritis cases and various categories of environmental sources, e.g., crustaceans, fish and different water samples (pond, stored, open well and tap water) were tested for their Kanagawa phenomenon and serotypic pattern. Amongst the 80 human isolates tested, 69 strains (86.3%) were Kanagawa phenomenon positive, and 60 strains (75.0%) were serologically typable--the dominant serotype being 05:K15. Of the 25 isolates from various water sources 10(40.0%) were Kanagawa phenomenon positive, and 17(68.0%) were serologically typable and 4 (23.5%) of them belonged to serotype 05:K15. All the 30 strains isolated from crustaceans and fish were Kanagawa phenomenon negative and 22 (73.3%) of them were serologically typable, belonging to heterogeneous serotypes. The results of this study also indicate the possible role of water in the transmission of V. parahaemolyticus infection in Calcutta slums.

Epidemiological and clinical profiles of acute invasive diarrhoea with special reference to mucoid episodes: a rural community-based longitudinal study.

A study was carried out in 3 villages near Calcutta, India, having a population of 5464, between August 1992 and December 1994. A cohort of rural children below 4 years of age was prospectively observed to determine the clinico-epidemiological aspects of mucoid diarrhoea and examine propensity to invasiveness. Overall, the incidence of diarrhoea was 1.7 episodes/child/year, and that of mucoid and bloody dysentery was 0.8 and 0.2 episodes/child/year, respectively. Children aged 6-11 months had a higher incidence of mucoid diarrhoea (1.3 episodes/child/year) and the peak season occurred in June and July. Multivariate analysis using logistic regression showed that mucoid diarrhoea and bloody dysentery were closely similar in both clinical and laboratory findings, including raised faecal leucocyte count (> 10/high power microscope field [hpf]). However, abdominal pain occurred more frequently in bloody dysentery than in mucoid diarrhoea. Faecal leucocyte count (> 10/hpf) can therefore be used as an indicator for invasiveness of mucoid diarrhoea at the community level.

In vitro antimicrobial activity of potash alum.

This study reports the bactericidal activity of potash alum when added to water, against various epidemic causing enteric pathogens like Vibrio cholerae 01, V. cholerae 0139 and Shigella dysenteriae 1 by lowering the pH of water (from 6.0 to 4.0). Growth of the enteric pathogens was monitored in vitro by inoculating broth cultures of the different organisms in distilled water containing increasing concentrations of potash alum and quantitatively determining the concentration of viable organisms over a 48 h period by the standard plate count method. Controls constituted cultures of each organism grown in the absence of potash alum. The pH of alum administered water was measured in each test tube before inoculation of organisms. Potash alum was found to inhibit growth (10(5) viable count per ml) of most of the organisms examined, particularly V. cholerae 01 and V. cholerae 0139 in a dose dependent fashion. Reduction of colony forming units was observed in presence of 0.25 g/dl of alum after 5 h and no growth was noticed after 24 h.

Validity of new phage typing scheme against Vibrio cholerae 01 biotype ElTor strains.

A total of 538 strains of V. cholerae 01 biotype ElTor were phage typed by the conventional Basu and Mukerjee and also the new typing scheme developed at the National Institute of Cholera and Enteric Diseases, Calcutta. The strains could be clustered into seven types by the new scheme as against only two by the conventional method. The results provide conclusive evidence on the validity of the new scheme for phage typing of V. cholerae strains.

Biological activity & interaction of Vibrio cholerae bacteriophages in rabbit ileal loop.

A set of ten V. cholerae EITor phages is in routine use for phage typing of V. cholerae O1 biotype EITor strains. These phages were used in rabbit ileal loop experiment to investigate whether these phages have any prophylactic value as regards their lytic capability on V. cholerae strains. The phages were found to have no prophylactic use as they were unable to lyse the standard bacterial strain V. cholerae MAK 757.

An outbreak of acute diarrhoeal disease amongst tribal population in Tripura.

A massive outbreak of acute diarrhoeal diseases occurred during March-April, 1992 in the north district of Tripura. Investigation of the outbreak revealed Vibrio cholerae 01 biotype ElT or as the main etiologic agent in 50 per cent of patients. The outbreak which started amongst the tribal population might have spread due to prevailing illiteracy, poverty, low personal and domestic hygiene and vulnerable water sources (chhara water).

A longitudinal study of diarrhoea among children in Calcutta communities.

PIP: A longitudinal study was conducted to determine the profile of diarrheal diseases in a group of 383 children below 5 years of age in 2 typical slums of Calcutta (India). The overall annual incidence of diarrheal illness in these children during the 1st year of the study was found to be 1.1/child. However, the incidence was higher (1.9/child) in children below 2 years of age and declined progressively with advancing age. Most (99.5%) of the diarrheal episodes were mild in nature and not a single child required hospitalization; about 53.4% children had no diarrheal symptoms. Enteropathogens identified in diarrheal stool samples from 13.7% of children included enteropathogenic Escherichia coli (5.8%), rotaviruses (5.6%), shigellae (3.5%), Salmonella spp, (1.0%), Entamoebae histolytica (0.9%), Giardia lamblia (0.4%), Vibrio cholerae (0.6%), and V. parahemolyticus (0.3%).^ieng

Acute diarrhoea caused by Vibrio mimicus in Calcutta.

Out of 539 acute diarrhoea cases studied, Vibrio mimicus was isolated as a sole pathogen in the faeces of 7 (1.3%) cases. The chief clinical presentations of the seven cases were watery diarrhoea and vomiting. Bloody diarrhoea was observed in 2 (28.5%), abdominal pain in 2 (28.57%) and fever in one (14.29) cases. All cases could be effectively treated with ORS except 3 (42.85%) cases who required IV Ringer's lactate. All V. mimicus strains isolated in the study were uniformly susceptible to tetracycline, chloramphenicol, norfloxacin and ciprofloxacin.

Prospective study of nosocomial enteric infections in a pediatric hospital, Calcutta.

Hospital acquired enteric infections were investigated by studying 3138 children under 5 years of age who were admitted without diarrhea in nine medical words of a pediatric hospital, Calcutta during the period between March and September 1987. Three hundred and twenty (10.2%) children developed nosocomial diarrhea during their hospital stay. Fecal samples from 178 nosocomial diarrhea, 345 hospitalized diarrhea cases, 178 hospital controls and 200 outpatient controls were collected for detection of established enteropathogens. There were no statistically significant differences in the detection of most of the enteropathogens from fecal samples of nosocomial diarrhea, hospitalized diarrhea and hospital controls. Enteric pathogens were detected at a higher frequency (statistically significant) from fecal samples of nosocomial diarrhea cases as compared to outpatient controls. This study highlights the importance of most of the enteropathogens like Shigella, Salmonella, rotavirus, enteropathogenic E. coli as the cause of hospital cross infection. This study reinforces the importance of developing preventive measures in order to reduce the frequency of illness.

Possibility of public health hazards by contamination of toxin producing Vibrio cholerae through fishes reared in sewage fed fishery.

This study was undertaken to explore the possibility of contamination of Vibrio cholerae serogroups 01 and 0139, the most important causative organisms for life threatening acute secretory diarrhoea and also potential public health importance, by isolating these organisms from body surface, gill and intestine of common table fishes like Labeo rhoita, Catla Catla, Cirrhinus mirgala and Tilapia mosambica which were reared in sewage and raw human excrita enriched fishery ponds. Vibrio Cholerae 01 or 0139 were not isolated from body surface swabs, gills and intestine of these common table fishes. Water samples of sewage enriched fishery ponds and sewage of Calcutta municipal corporation were also processed for isolation of these organisms, however, these samples were also negative for V. Cholerae 01, 0139 and non 01-0139 serogroups. Present study indicated that there was less chance of contamination of toxigenic and disease producing strains of V. cholerae by common table fishes which were reared in sewage and raw faecal matter enriched fishery ponds.

Enteropathogens associated with acute diarrhoeal diseases.

PIP: Five types of Escherichia coli are responsible for as much as 25% of all diarrheal diseases in developing countries. They tend to be transmitted via contaminated foods, particularly weaning foods, and water. They include enterotoxigenic, enteropathogenic, enteroadherent, enteroinvasive, and enterohemorrhagic E. coli. Shigella species are responsible for 10-15% of acute diarrheas in children less than 5 years old and the most common etiologic agents of childhood dysentery. Shigellosis is common in the warm season. An outbreak of shigella dysentery in West Bengal, India, had a high attack rate in children less than 5 years old and was resistant to many drugs. Nontyphoid Salmonella species cause watery diarrhea with nausea, cramps, and fever. Worldwide, various Salmonella strains exhibit resistance to ampicillin, chloramphenicol, and co-trimoxazole. Campylobacter jejuni produces watery diarrhea which, in 33% of cases and 1-2 days after onset, contains blood and mucus. Many normal healthy children in developing countries are carriers of C. jejuni. Vibrio cholerae O1 is endemic in parts of Africa and Asia (e.g., 5-10% of hospitalized diarrhea patients). The ElTor cholera biotype is responsible for the 7th pandemic. Other bacterial enteropathogens are Aeromonas species, Bacteroides fragilis, and Providencia alcalifaciens. Rotavirus is a major cause of sporadic and epidemic diarrhea among 6-23 month olds. Its incidence peaks in cold or dry seasons. Other viral enteropathogens are Norwalk virus, adenoviruses, astroviruses, and coronaviruses. In India, the prevalence of Entamoeba histolytica varies from 3.6% to 47.4%. It occurs equally in high and low socioeconomic classes. Giardia lamblia usually infects 1-5 year old children. Its transmission routes are food, water, and the fecal-oral route. Cryptosporidia produce acute watery diarrhea, especially in children less than 2 years old. Cryptosporidia diarrhea is common among AIDS patients. Oral rehydration therapy and proper feeding during and after diarrhea reduces deaths from diarrhea.^ieng

Prevalência dos indicadores de risco para perda auditiva nos resultados 'falha' da triagem auditiva neonatal / Prevalence of risk indices for hearing loss in 'failure' results of newborn hearing screening

OBJETIVO: estabelecer qual indicador de risco para perda auditiva apresenta maior prevalência de resultados 'falha' da Triagem Auditiva Neonatal. MÉTODOS: a partir de análise retrospectiva de 702 prontuários de lactentes submetidos à triagem auditiva neonatal no Ambulatório de Audiologia da Universidade Federal da Bahia no período de 2007 a 2011, foi realizado o teste do qui-quadrado para a hipótese de ausência de associação entre os indicadores de risco e a 'falha' da Triagem Auditiva Neonatal. RESULTADOS: dos lactentes pesquisados, 352 (50,29%) foram do sexo masculino e 348 (49,71%) do sexo feminino, dois não tinham referências quanto ao gênero. A maioria dos bebês tinha idade entre um a três meses de vida e 45,40% dos bebês nasceram prematuros. Verificou-se que os bebês apresentaram os seguintes indicadores de risco: 28,83% tinham hiperbilirrubinemia; 22,54% tinham história de infecção congênita; 15,06% nasceram com peso inferior a 1.500g; 8,21% tiveram boletim Apgar de 0 a 4 no 1º minuto; 5,07% apresentaram boletim Apgar de 0 a 6 no 5º minuto; 9,09% receberam ventilação mecânica; 4,09% tinham síndromes associadas à perda auditiva e apenas 1 (0,84%) lactente teve meningite bacteriana. Entre esses lactentes, 92,45% não tinham histórico familiar de deficiência auditiva e 97,09% não apresentavam malformação craniofacial. CONCLUSÃO: houve associações entre cinco indicadores de risco e 'falha' na triagem auditiva neonatal. Os indicadores de risco apresentaram a seguinte ordem decrescente de prevalência: boletim de Apgar de 0 a 4 no 1º minuto; malformações craniofaciais; síndrome associadas a perdas auditivas; boletim de Apgar de 0 a 6 no 5º minuto; ventilação mecânica. .

PURPOSE: to establish which risk index for hearing loss shows the highest prevalence of 'failure' in newborn hearing screening. METHODS: using a retrospective analysis of medical records involving 702 infants undergoing neonatal hearing screening in the Audiology Clinic of the Federal University of Bahia in the period 2007-2011, the chi-square test was carried out for the hypothesis of no association between the risk indices and 'failure' of the newborn hearing screening. RESULTS: in relation to the infants studied, 352 (50.29%) were male and 348 patients (49.71%) were females, two had no references as to their gender. Most babies were between one to three months of age and 45.40% of babies were born prematurely. It was found that infants showed the following risk indices: 28.83% had hyperbilirubinemia; 22.54% had a history of congenital infection; 15.06% were born weighing less than 1,500 grams; 8.21% had Apgar scores of 0-4 in the 1st minute; 5.07% had Apgar scores 0-6 in the 5th minute; 9.09% received artificial respiration; 4.09% had syndromes associated with hearing loss and only 1 (0.84%) infant had bacterial meningitis. Among these infants, 92.45% had no family history of hearing impairment and 97.09% had no craniofacial malformation. CONCLUSION: there were associations between five risk indices and 'failure' in neonatal hearing screening. Risk indices showed the following decreasing order of prevalence: Apgar score 0-4 in the 1st minute; craniofacial malformations; syndromes associated with hearing loss; Apgar score 0-6 in the 5th minutes; artificial respiration. .