Psychrotolerant Anaerobes from Lake Podprudnoe, Antarctica and Penguin Spheniscus demersus Colony, South Africa

The study of a sample collected from a wind-made ice sculpture near Lake Podprudnoe, Antarctica led to the isolation of the psychrotolerant strain ISLP-3. Cells of the new isolate are vibrio-shaped that measure 0.5 x 1.0-3.0 micron in size. Growth occurs within the temperature range 5-35 C with the optimum at 22 C. Salinity range for growth is 0-2 % NaCl with the optimum at 0.25 %. The new isolate grows within a pH range from 6.0 to 9.5 with the optimum at 7.5. Strain ISLP-3 is saccharolytic, growing on the following substrates: D-glucose, D-ribose, D-fructose, D-arabinose, maltose, sucrose, D-trehalose, D-mannose, D-cellobiose, lactose, starch, chitin, triethylamine, N-acetylglucosamine, and urea. The best growth occurred on D-cellobiose. An environmental sample of pond water near a colony of the endemic species of African penguins, Spheniscus demersus, was collected in February 2008 and delivered directly to the Astrobiology laboratory at NSSTC. The microbiological study of this sample led to the isolation of two psychrotolerant strains ARHSd-7G and ARHSd-9G. Both strains are strictly anaerobic bacteria and are able to grow at high pH and low temperatures. The cells of strain ARHSd-7G are motile, vibrio-shaped, spore-forming cells. Optimal growth of this strain occurs at 30 C, 3 % NaCl, and pH 8.9. The isolate ARHSd-7G combines sugarlytic and proteolytic metabolisms, growing on some proteolysis products including peptone and yeast extract and a number of sugars. The second isolate, ARHSd-9G, exhibits thin, elongated rods that measure 0.4 x 3-5 micron. The cells are motile and spore-forming. Optimal growth of strain ARHSd-9G occurs at 30 C, 1.75 % NaCl, and pH 8.5. The strain ARHSd-9G is sugarlytic, growing well on substrates such as D-glucose, sucrose, D-cellobiose, maltose, fructose, D-mannose, and trehalose (the only exception is positive growth on yeast extract). In this report, the physiological and morphological characteristics of the novel psychrotolerant, alkaliphilic, and neutrophilic isolates from the Antarctica 2008 expedition will be discussed

Anaerobic Psychrophiles from Lake Zub and Lake Untersee, Antarctica

The study of samples from Antarctica 2008 and 2009 expeditions organized and successfully conducted by Richard Hoover led to the isolation of diverse anaerobic strains with psychrotolerant and psychrophilic physiology. Due to the fact that Lake Untersee has never been subject to microbiological study, this work with the samples has significant and pioneering impact to the knowledge about the biology of this unique ecosystem. Also, the astrobiological significance for the study of these ecosystems is based on new findings of ice covered water systems on other bodies of our solar system. Anaerobic psychrotolerant strain LZ-22 was isolated from a frozen sample of green moss with soils around the rhizosphere collected near Lake Zub in Antarctica. Morphology of strain LZ-22 was observed to be motile, rod shaped and spore-forming cells with sizes 1 x 5-10 micron. This new isolate is a mesophile with the maximum temperature of growth at 40C. Strain LZ-22 is able to live on media without NaCl and in media with up to 7% (w/v) NaCl. It is catalase negative and grows only on sugars with the best growth rate being on lactose. The strain is a neutrophile and grows between pH 5 and 9.0 with the optimum at 7.8. Another two strains UL7-96mG and LU-96m7P were isolated from deep water samples of Lake Untersee. Proteolytic strain LU-96m7P had a truly psychrophilic nature and refused to grow at room temperature. Sugarlytic strain UL7-96mG was found to be psychrotolerant, but its rate of growth at 3C was very high compared with other mesophiles. Two homoacetogenic psychrophilic strains A7AC-96m and AC-DS7 were isolated and purified from samples of Lake Untersee; both of them are able to grow chemolithotrophically on H2+CO2. In the presence of lactate, these strains are able to grow only at 0-18C, and growth at 22C was observed only with yeast extract stimulation. In this paper, physiological and morphological characteristics of novel psychrophilic and psychrotolerant isolates from Antarctica 2008 and 2009 expeditions will be discussed

Vessel Reactivity and Blood Flow in Rats Exposed to Neonatal Supplemental Oxygen

Premature babies make up 12.8% of live births per year. Because their lungs are poorly developed, supplemental oxygen is a necessary treatment. Recent studies in our laboratory, in a rat model of prematurity, show that aortic pulse wave velocities were higher in rats exposed to neonatal supplemental oxygen. This is an indicator of significant aortic stiffening. This study aims to determine if supplemental oxygen also affects the downstream vasculature reactivity. We hypothesized that exposure to supplemental oxygen during the neonatal period will decrease vessel reactivity and we will observe smaller changes in blood flow with hypoxic and carbon dioxide challenges. Twelve month old rats exposed to 80% and 21% oxygen for eight days during the neonatal period were ventilated with hypoxic (12% O2), hypercapnic (5% CO2), and room air conditions. Each exposure lasted 10 minutes and followed with different 10 µm neutron-activated BioPAL microspheres injections into the left ventricle. The microspheres were allowed to circulate for 300-400 cardiac cycles. Microspheres lodged in the tissues were used to quantify changes in visceral blood flow. 80% O2 exposed rats showed a decreased baseline cardiac output to tissues compared to controls. In hypoxic and carbon dioxide conditions, 80% O2 exposed rats showed decreased changes in blood flow to tissues compared to controls, but results were not significant. Some tissues showed decreased blood flows when the rats were exposed to hypoxia and carbon dioxide challenges suggesting some vasoconstrictive effects had also occurred

Effects of Neonatal Supplemental Oxygen and High Fat Diet on Weight Gain, Ventricular Hypertrophy and Contractility

Premature birth represents about 13% of live births each year. Since lungs of these infants are underdeveloped, they receive supplemental oxygen right after birth, but little is known about its effects on the development of normal physiological responses and whether it impacts long-term cardio-metabolic function. Based on previous studies from our lab that showed increased pulse wave velocity in 12 month old rats exposed to neonatal supplemental oxygen, we hypothesized that neonatal exposure to supplemental oxygen causes cardiac hypertrophy and decreased left ventricular contractility. We also hypothesized that these effects to supplemental oxygen would be enhanced by 10 weeks on a high fat diet. To test the hypothesis, we used our rat model of 80% and 21% O2 exposed rats to FlO2=0.80 and 0.21 respectively, for 8 days post-birth. Two months after birth, these 80% and 21% rats were randomly assigned to either a high fat diet (60% of calories from animal fat) or low fat diet (CON) for 10 weeks during which their weights and caloric consumption were monitored. After 10 weeks, a Miller conductance catheter was inserted into the left ventricle to obtain pressure-volume loops and end-systolic pressure volume relationship, which was used to evaluate contractility. 80% rats exposed to CON diet showed higher cumulative weight gain than 21% rats on the same diet. No significant difference was observed between the weights of the left ventricles due to exposure to supplemental oxygen or high fat diet. Neonatal supplemental oxygen exposure decreased contractility whereas the combination of high fat diet and supplemental oxygen exposure reversed this effect. These data suggest that neonatal exposure to supplemental oxygen promotes weight gain and decreased ventricular contractility

Neonatal Supplemental Oxygen Exposure Promotes the Development of Metabolic Disease in Adult Rats

Premature infants frequently require supplemental oxygen to sustain life, but little is known about how supplemental oxygen administered during the critical developmental window after birth increases the risk of age-related disease, including obesity and diabetes. We hypothesized that neonatal rats exposed to supplemental oxygen (OXY) would have impaired glucose tolerance and that they would develop a diabetes phenotype earlier than controls (CON), when offered a high fat diet. We used an established rat model of neonatal oxygen exposure (80% O2 for 8-14 days) and glucose tolerance was evaluated 14 days and 12 months post-natally. To evaluate glucose tolerance, baseline blood glucose was measured after an overnight fast, followed by an intraperitoneal injection of concentrated glucose. Blood glucose was then measured 15, 30, 60 and 120 minutes post-injection. In a second experiment, two month old OXY and CON rats were randomly assigned to an animal-based fat diet (60% of calories from fat), or standard, low fat diet for ten weeks. At the beginning of the study and each subsequent week, glucose tolerance was measured. At 14 days and 12 months, OXY rats had higher blood glucose at 15 and 30 minutes compared to CON rats. OXY rats fed a high fat diet developed frank glucose intolerance after 4 weeks. Ten weeks of high fat diet had minimal effect on glucose tolerance in CON rats. Taken together, these data suggest that supplemental oxygen during the neonatal period may predispose the premature infant to the development of metabolic disease later in life

STS Research Agenda Task Force: Survey Results

As part of our charge to provide STS members with recommended areas for exploration in science and technology library research, we sent out a survey in the Fall of 2014. The 258 responses helped create a snapshot of what areas are currently being researched and what could be important areas of future research.Poster presented at the ACRL 2015 Conference in Portland, OR.UT Librarie

Healthcare outcomes in undocumented immigrants undergoing two emergency dialysis approaches

BACKGROUND: Current estimates suggest 6,500 undocumented end-stage renal disease (ESRD) patients in the United States are ineligible for scheduled hemodialysis and require emergent dialysis. In order to remain in compliance with Emergency Medicaid, an academic health center altered its emergency dialysis criteria from those emphasizing interdialytic interval to a set emphasizing numerical thresholds. We report the impact of this administrative change on the biochemical parameters, utilization, and adverse outcomes in an undocumented patient cohort. METHODS: This retrospective case series examines 19 undocumented ESRD patients during a 6-month transition divided into three 2-month periods (P1, P2, P3). In P1, patients received emergent dialysis based on interdialytic interval and clinical judgment. In P2 (early transition) and P3 (equilibrium), patients were dialyzed according to strict numerical criteria coupled with clinical judgment. RESULTS: Emergent criteria-based dialysis (P2 and P3) was associated with increased potassium, blood urea nitrogen (BUN), and acidosis as compared to P1 (p < 0.05). Overnight hospitalizations were more common in P2 and P3 (p < 0.05). More frequent adverse events were noted in P2 as compared to P1 and P3, with an odds ratio (OR) for the composite endpoint (intubation, bacteremia, myocardial infarction, intensive care unit admission) of 48 (5.9 - 391.2) and 16.5 (2.5 - 108.6), respectively. Per-patient reimbursement-to-cost ratios increased during criteria-based dialysis periods (P1: 1.49, P2: 2.3, P3: 2.49). DISCUSSION: Strict adherence to criteria-based dialysis models increases biochemical abnormalities while improving Medicaid reimbursement for undocumented immigrants. Alternatives to emergent dialysis are required which minimize cost, while maintaining dignity, safety, and quality of life.

Hispanic Ethnicity and Post-traumatic Stress Disorder after a Disaster: Evidence from a General Population Survey after September 11,2001

PURPOSE: To assess ethnic differences in the risk of post-traumatic stress disorder (PTSD) after a disaster, and to assess the factors that may explain these differences. METHODS: We used data from a representative survey of the New York City metropolitan area (n = 2616) conducted 6 months after September 11, 2001. Linear models were fit to assess differences in the prevalence of PTSD between different groups of Hispanics and non-Hispanics and to evaluate potential explanatory variables. RESULTS: Hispanics of Dominican or Puerto Rican origin (14.3% and 13.2%, respectively) were more likely than other Hispanics (6.1%) and non-Hispanics (5.2%) to report symptoms consistent with probable PTSD after the September 11 terrorist attacks. Dominicans and Puerto Ricans were more likely than persons of other races/ethnicities to have lower incomes, be younger, have lower social support, have had greater exposure to the September 11 attacks, and to have experienced a peri-event panic attack upon hearing of the September 11 attacks; these variables accounted for 60% to 74% of the observed higher prevalence of probable PTSD in these groups. CONCLUSION: Socio-economic position, event exposures, social support, and peri-event emotional reactions may help explain differences in PTSD risk after disaster between Hispanic subgroups and non-HispanicsPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/40349/2/Galea_Hispanic Ethnicity and Post-Traumatic Stress Disorder_2004.PD

Multicenter observational study on factors and outcomes associated with various methicillin-resistant Staphylococcus aureus types in children with cystic fibrosis

Rationale: Methicillin-resistant Staphylococcus aureus (MRSA) prevalence continues to increase in patients with cystic fibrosis (CF) in the United States, reaching 26.5% in 2012. Approximately 30% of strains are SCCmec (staphylococcal cassette chromosome mec) IV type, frequently USA300, which in the general population have different genotypic and phenotypic features than SCCmec II type. Objectives: We hypothesized that risk factors for acquisition and outcomes in patients with CF differed for "health care-associated" (SCCmec II) versus "community-associated" (SCCmec IV)MRSAstrains. Methods: To determine the role of SCCmec type and Panton-Valentine leukocidin (PVL), MRSA isolates from patients not more than 18 years old at seven CF centers were typed and the association of potential risk factors and subsequent clinical course was assessed, using data provided by the CF Patient Registry. Measurements and Main Results: Participants with chronic MRSA (295) had typeable isolates and clinical data; 205 (69.5%) had SCCmec II PVL(-), 39 (13.2%) had SCCmec IV PVL(-), and 51 (17.3%) had SCCmec IVPVL(1) strains.SCCmec IV, comparedwith SCCmec II, increased during the study period, 1996-2010 (P = 0.03). SCCmec II was associated with Pseudomonas aeruginosa-positive cultures and three or more clinic visits in the 6 months preceding the first positive MRSA culture (adjusted odds ratio, 2.05; 95% confidence interval, 1.13-3.74; P = 0.019). Lung function and anthropometrics remained unchanged in the 6 months after initial MRSA detection compared with the 6 months prior. Although CF care increased for participants in both groups in the 6 months after MRSA detection, inhaled antibiotics were prescribed more frequently in those with SCCmec II strains and increased hospitalizations occurred in those with SCCmec IV PVL(-) strains compared with those with PVL(1) strains (adjusted difference, 34.10%; 95% confidence interval, 7.58-60.61; P = 0.012). Participants in both groups had an increase in CF care in the 2 years after MRSA detection compared with the 2 years prior. Conclusions: Increased exposure to CF clinics and P. aeruginosa may constitute risk factors for acquisition of SCCmec II MRSA strains. Clinical interventions increased 6 months and 2 years after initial MRSA detection regardless of SCCmec type

Microbiological efficacy of early MRSA treatment in cystic fibrosis in a randomised controlled trial

OBJECTIVE: To evaluate microbiological effectiveness, that is, culture negativity of a non-blinded eradication protocol (Rx) compared with observation (Obs) in clinically stable cystic fibrosis participants with newly positive methicillin resistant Staphylococcusaureus (MRSA) cultures. DESIGN: This non-blinded trial randomised participants ages 4-45 years with first or early (≤2 positive cultures within 3 years) MRSA-positive culture without MRSA-active antibiotics within 4 weeks 1:1 to Rx or Obs. The Rx protocol was: oral trimethoprim-sulfamethoxazole or if sulfa-allergic, minocycline plus oral rifampin; chlorhexidine mouthwash for 2 weeks; nasal mupirocin and chlorhexidine body wipes for 5 days and environmental decontamination for 21 days. The primary end point was MRSA culture status at day 28. RESULTS: Between 1 April 2011 to September 2014, 45 participants (44% female, mean age 11.5 years) were randomised (24 Rx, 21 Obs). At day 28, 82% (n=18/22) of participants in the Rx arm compared with 26% (n=5/19) in the Obs arm were MRSA-negative. Adjusted for interim monitoring, this difference was 52% (95% CI 23% to 80%, p<0.001). Limiting analyses to participants who were MRSA-positive at the screening visit, 67% (8/12) in the Rx arm and 13% (2/15) in the Obs arm were MRSA-negative at day 28, adjusted difference: 49% (95% CI 22% to 71%, p<0.001). Fifty-four per cent in the Rx arm compared with 10% participants in the Obs arm remained MRSA-negative through day 84. Mild gastrointestinal side effects were higher in the Rx arm. CONCLUSIONS: This MRSA eradication protocol for newly acquired MRSA demonstrated microbiological efficacy with a large treatment effect. TRIAL REGISTRATION NUMBER: NCT01349192