Impact of different carbapenemase-producing Enterobacterales screening strategies in a hospital setting.

BACKGROUND: The spread of carbapenemase-producing Enterobacterales (CPE) is a global health problem. Gastrointestinal tract carriage makes faeces or rectal swabs the recommended screening methods. AIM: To assess the impact of three laboratory screening strategies for CPE on positivity rates and infection prevention and control in a hospital setting in North West England from 2015 to 2017. METHODS: In a retrospective study, time to CPE-positive and -negative results, number of new CPE-positive patients identified, and number of hospital bed-days lost/wards affected were measured for each of three CPE screening strategies; culture plus phenotypic tests, culture plus polymerase chain reaction (PCR), and PCR only (phases 1, 2 and 3, respectively). FINDINGS: The fastest time to CPE results was PCR only (median: 4.0 h), then culture plus PCR (median: 47.6 h), then culture plus phenotypic tests (median: 49.8 h) (P < 0.001). The mean numbers of hospital bed-days lost per month decreased between phases 2 and 3 (P = 0.01). The mean number of wards/units affected by CPE increased from phase 1 (2.57) to phase 2 (7.71), then decreased in phase 3 (3.86). The percentage positivity rate for phases 1, 2, and 3 were 2.01, 1.38, and 1.55 respectively. From May to October, the number of new CPE-positive patients was lower for phases 1 and 3 than for phase 2. During all three phases there was a peak in the number of newly identified CPE carriers in August. CONCLUSION: This study provides evidence that using a rapid PCR to screen rectal or faeces swabs enables more timely infection prevention and control measures when compared with culture-based methods. A reduction in bed-days lost due to CPE was observed when rapid molecular screening was introduced.

23Na(α,p)26Mg Reaction Rate at Astrophysically Relevant Energies.

The production of 26Al in massive stars is sensitive to the 23Na(α,p)26Mg cross section. Recent experimental data suggest the currently recommended cross sections are underestimated by a factor of ∼40. We present here differential cross sections for the 23Na(α,p)26Mg reaction measured in the energy range E(c.m.)=1.7-2.5 MeV. Concurrent measurements of Rutherford scattering provide absolute normalizations that are independent of variations in target properties. Angular distributions are measured for both p0 and p1 permitting the determination of total cross sections. The results show no significant deviation from the statistical model calculations upon which the recommended rates are based. We therefore retain the previous recommendation without the increase in cross section and resulting stellar reaction rates by a factor of 40, impacting the 26Al yield from massive stars by more than a factor of 3.

Test of sum rules in nucleon transfer reactions.

The quantitative consistency of nucleon transfer reactions as a probe of the occupancy of valence orbits in nuclei is tested. Neutron-adding, neutron-removal, and proton-adding transfer reactions were measured on the four stable even Ni isotopes, with particular attention to the cross section determinations. The data were analyzed consistently in terms of the distorted wave Born approximation to yield spectroscopic factors. Valence-orbit occupancies were extracted, utilizing the Macfarlane-French sum rules. The deduced occupancies are consistent with the changing number of valence neutrons, as are the vacancies for protons, both at the level of <5%. While there has been some debate regarding the true "observability" of spectroscopic factors, the present results indicate that empirically they yield self-consistent results.

Comparison of rectal and tympanic core body temperature measurement in adult Guyanese squirrel monkeys (Saimiri sciureus sciureus).

BACKGROUND: Measuring core body temperature in a manner that is safe for animals and veterinary personnel is an important part of a physical examination. For nonhuman primates, this can involve increased restraint, additional stress, as well as the use of anesthetics and their deleterious effects on body temperature measurements. The purpose of this study was to compare two non-invasive methods of infrared tympanic thermometry to standard rectal thermometry in adult squirrel monkeys. METHODS: Tympanic temperatures were collected from 37 squirrel monkeys and compared to rectal temperatures using a human and veterinary infrared tympanic thermometer. RESULTS: Compared with rectal temperature measurements, the human tympanic thermometer readings were not significantly different, while the veterinary tympanic thermometer measurements were significantly higher (P<0.05). There were no differences between sexes. CONCLUSIONS: The tympanic thermometer designed for use in humans can be used in adult squirrel monkeys as an alternative to rectal thermometry for assessing core body temperature.

Anaerobic biodegradation of BTEX using Mn(IV) and Fe(III) as alternative electron acceptors.

Anaerobic BTEX biodegradation was tested in batch experiments using an anaerobic sediment as inoculum under Fe(III) and Mn(IV) reducing conditions. All BTEX were degraded under the conditions tested, specially under Mn(IV) reducing conditions, where benzene was degraded at a rate of 0.8 micromol l(-1) d(-1), significantly much faster than Fe(III) reducing conditions. Under Fe(III) reducing conditions, ethylbenzene was the compound that degraded at the faster rate of 0.19 micromol l(-1) d(-1). Mn(IV) reducing conditions are energetically more favourable than Fe(III), therefore, BTEX were more rapidly degraded under Mn(IV) reducing conditions. These results represent the first report of the degradation of benzene with Mn(IV) as the final electron acceptor. Amorphous manganese oxide is a natural widely distributed metal in groundwater, where it can be microbiologically reduced, leading to the degradation of monoaromatic compounds.

Removal of phenanthrene from soil by co-cultures of bacteria and fungi pregrown on sugarcane bagasse pith.

Sixteen co-cultures composed of four bacteria and four fungi grown on sugarcane bagasse pith were tested for phenanthrene degradation in soil. The four bacteria were identified as Pseudomonas aeruginose, Ralstonia pickettii, Pseudomonas sp. and Pseudomonas cepacea. The four fungi were identified as: Penicillium sp., Trichoderma viride, Alternaria tenuis and Aspergillus terrus that were previously isolated from different hydrocarbon-contaminated soils. Fungi had a statistically significant positive (0.0001

Respiratory tract toxicity in rats exposed to Mexico City air.

The rat has been used extensively as a health sentinel, indicator, or monitor of environmental health hazards, but this model has not been directly validated against human exposures. Humans in Mexico City show upper respiratory tract lesions and evidence of pulmonary damage related to their environmental inhalation exposure. In this study, male and female F344 rats were exposed (23 hr/day) in Mexico City to local Mexico City air (MCA)* for up to seven weeks. Controls were maintained at the same location under filtered air. Prior to these exposures, several steps were taken. First, the nasal passages of normal male rats shipped from the United States and housed in Mexico City were examined for mycoplasma infection; no evidence of infection was found. In addition, a mobile exposure and monitoring system was assembled and, with an ozone (O3) exposure atmosphere, was tested along with supporting histopathology techniques and analysis of rat nasal and lung tissues. Last, the entire exposure model (equipment and animals) was transported to Mexico City and validated for a three-week period. During the seven-week study there were 18 one-hour intervals during which the average O3 concentration of MCA in the exposure chamber exceeded the US National Ambient Air Quality Standard (NAAQS) of 0.120 ppm 03 (hourly average, not to be exceeded more than once per year). This prolonged exposure of healthy F344 rats to MCA containing episodically low to moderate concentrations of 03 (as well as other urban air pollutants) did not induce inflammatory or epithelial lesions in the nasal airways or lung as measured by qualitative histologic techniques or quantitative morphometric techniques. These findings agree with those of previous controlled O3 inhalation studies, but they are in contrast to reports indicating that O3-polluted MCA causes significant nasal mucosal injury in adults and children living in southwestern Mexico City. Taken together, these findings may suggest that human airways are markedly more susceptible to the toxic effects of MCA than are the airways of the F344 rat.

Petroleum asphaltenes: generated problematic and possible biodegradation mechanisms.

Petroleum asphaltenes are hydrocarbons that present an extremely complex molecular structure. They are conformed by different proportions of nitrogen, sulfur and oxygen. These compounds cause diverse problems like the blockage of crude oil extraction and transport pipes, the reduction of their economic use and the pollution of ecosystems. Biodegradation of asphaltenes is an important process that can eliminate these compounds and reduce the problems they cause. However, it is a process that occurs naturally in very reduced proportions. The purpose of this revision is to show the chemical structure of these compounds, the problems they cause and to represent their possible biodegradation mechanisms, based on the processes known for other hydrocarbons of complex structure. Elimination of the micelar structure, through the application of non-polar solvents, and fragmentation of the asphaltenes through photooxidation are the initial processes necessary to be able to degrade these compounds. The produced structures, such as the heteropolyaromatic and aromatic, lineal and ramified hydrocarbons, could be degraded in this order through biochemical reactions, such as omega oxidations, beta oxidations and aromatic oxidations respectively. These processes are distributed in an important variety of microorganisms. The elimination period's length can vary from one week, for the simplest structures, to 990 days for those with several condensed aromatic rings.

Framework for analyzing health care models serving adults with mental retardation and other developmental disabilities.

A conceptual framework was presented for describing, comparing, and analyzing the structure of health care models serving adults with mental retardation/developmental disabilities (MR/DD). This framework, which was drawn from Donabedian's (1980) work on the components of quality of health care-structure, process, and outcome-provides a basis for comparing health service models according to three key domains: measures of access, comprehensiveness, and cost. We used this framework to describe three existing programs that use different models to serve this population.

[Biological flow tracers: growth and survival of Bacillus subtilis 65-8 under environmental stress]. / Trazadores biológicos de flujos: crecimiento y sobrevivencia de Bacillus subtilis 65-8 bajo estrés ambiental.

Microbial flow tracers are presently limited to a strain of Bacillus globigii and a few highly specific bacteriophages. Bacillus subtilis 65-8 produces a black pigment as part of the primary metabolism under minimal nutritional conditions, with glucose as the sole carbon and energy source. This work shows that Bacillus subtilis 65-8 spores are thermostable (55 degrees C during 150 días), halotolerant (they germinate and grow in an enriched medium with up to 12% NaCl), persistent in a system of sand-soil and sewage, even in the presence of added commercial oil derivatives (kerosene, leaded gasoline and unleaded diesel), they are capable to move through porous systems even as the liquids, viscous as they may be, move through. Moreover, spores were resistant to the presence of autochtonous microorganisms in sewage, where we did not detect any other organism with differential characteristics like our strain (black pigment production in minimal medium) which could interfere with the identification of our biological flow tracer. The characteristics of Bacillus subtilis 65-8 make it a suitable biological flow tracer.

[Classification of Klebsiella strains with lectins]. / Clasificación de cepas de Klebsiella con lectinas.

Fourteen different plant seeds were used to obtain lectins which in turn were used to agglutinate 72 different serological strains of Klebsiella. The results were used to design a scheme which distinguishes 62 serotypes (91.6%) with a unique agglutination pattern with lectins. Two pairs of strains as well as two sets of three strains gave the same patterns. This procedure is useful as an alternative in the identification of strains for epidemiological purposes.

A hepatitis B vaccination program in a community teaching hospital.

Prior to offering the hepatitis B (HB) vaccine, a prescreen for hepatitis B virus (HBV) antibodies was conducted in a 565 bed hospital in Pasadena, California. Antibodies to the hepatitis B virus were detected in 14.5% of 1,745 employees tested. There was a significantly higher prevalence in those with a previous history of hepatitis, blood transfusions, exposure to needlesticks, number of years in the same occupation, and in the same hospital work area. Employees of Asian extraction (33.3%) and blacks (23.1%) had a higher prevalence of antibodies to the hepatitis B virus than Hispanics (13.7%) and whites (10.2%). Anti-HBs was detected in 92.6% of 865 employees who received three doses of the hepatitis B vaccine. Only 28.6% of nonresponders receiving a fourth dose of hepatitis B vaccine produced anti-HBs. The nonresponders to the HB vaccine were older (average age 64.9 years) when compared to the responders (average age 37.5 years), and more males failed to produce anti-HBs after vaccination than females. Hepatitis B vaccination of the majority of individuals with either "low level" anti-HBs alone or anti-HBc alone did not elicit an anamnestic response after one dose of vaccine, implying that these "low level" antibodies are nonspecific and do not represent antiviral antibodies. Adverse reactions to the hepatitis B vaccine were minor and included a flu-like syndrome, sore arm, and rash and swelling at the injection site. The reasons for nonparticipation were obtained from 179 individuals, and the main issue was concern about safety of the hepatitis B vaccine.