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1.
BMC Infect Dis ; 16: 275, 2016 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-27287441

RESUMO

BACKGROUND: We investigated the molecular mechanism of ß-lactam resistance in extended-spectrum ß-lactamase (ESBL)-producing Enterobacterial strains isolated in neonatal units of different hospitals in Anatnanarivo, Madagascar. METHODS: Bacteria were identified by standard biochemical methods, disc diffusion antibiograms and Etest. Resistance genes were sought by PCR. Strains were characterized by Rep-PCR (Diversilab), plasmid analysis and rep-typing. RESULTS: From April 2012 to March 2013, 29 ESBL-producing E. cloacae and 15 K. pneumoniae were isolated from blood culture (n = 32) or gastric samples (n = 12) performed at day 0 or 2 from 39/303 newborns suspected of early neonatal infection. These infants were treated with expanded spectrum cephalosporins, due to lack of carbapenems, leading to a high mortality rate (45 %). Isolates recovered were all, but 4, multidrug resistant, particularly to fluoroquinolones (FQ) except for 21 E. cloacae isolates. Isolates produced TEM-1 and CTX-M-15 ß-lactamases and their genes were located on several self-transferable plasmids of variable sizes sizes that could not be linked to a major plasmid incompatibility group. E. cloacae isolates belonged to 6 Rep-types among which two counted for 11 isolates each. The FQ resistant E. cloacae isolates belonged to one clone, whereas the FQ susceptible E. cloacae isolates belonged to four clones. The K. pneumoniae isolates belonged to 9 Rep-types among which one included five isolates. CONCLUSION: This study is the first molecular characterization of ESBL-producing isolates from neonatology units in Madagascar, a country with limited epidemiological data. It revealed an important multi-clonal dissemination of CTX-M-15-producing isolates reflecting both the high community carriage and the very early nosocomial contamination of the neonates.


Assuntos
Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Enterobacter cloacae/genética , Infecções por Enterobacteriaceae/microbiologia , Doenças do Recém-Nascido/microbiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , beta-Lactamases/genética , Antibacterianos/uso terapêutico , DNA Bacteriano/genética , Eletroforese em Gel de Campo Pulsado , Enterobacter , Enterobacter cloacae/isolamento & purificação , Enterobacter cloacae/metabolismo , Infecções por Enterobacteriaceae/tratamento farmacológico , Feminino , Humanos , Lactente Extremamente Prematuro , Recém-Nascido , Doenças do Recém-Nascido/tratamento farmacológico , Criança Pós-Termo , Recém-Nascido Prematuro , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/metabolismo , Madagáscar , Masculino , Testes de Sensibilidade Microbiana , Plasmídeos , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , beta-Lactamases/metabolismo
2.
J Dairy Sci ; 98(8): 5726-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26026760

RESUMO

The objective of this study was to compare the effect of 4 antiseptic compounds on the healing rate and incidence of infection of umbilical cords in newborn calves (n=60). Late gestation Jersey cows were monitored at a commercial farm (Sioux Jersey, Salix, IA) and newborn purebred (n=30) and crossbred (n=30) calves were obtained within 30min after birth. Calves were alternately assigned by birth order to 4 treatment groups: 7% tincture of iodine, 0.1% chlorine created using a novel chlorine disinfectant technology, chlorohexidine gluconate 4.0% wt/vol, and 10% trisodium citrate. Prior to dipping (within 30min of birth), diameter of the umbilical cords (as an indicator of cord drying and healing) were determined using digital calipers. In addition, as an indicator of umbilical infections, surface temperature of the umbilical stump (along with a reference point at the midpoint of the sternum) was determined using a dual-laser infrared thermometer. These measurements were all repeated at 24±1 h of age. All data were analyzed using mixed model methods. All models included fixed effects of breed (Jersey or Jersey cross), sex (bull or heifer), and treatment. Fixed effect interactions were not included in the statistical model due to the relatively small sample size. No treatment differences were noted for healing rate of umbilical cords. Initially, mean umbilical cord diameter was 22.84±3.89mm and cords healed to a mean diameter of 7.64±4.12mm at 24 h of age. No umbilical infections were noted for calves on any treatment during the course of this study. Mean surface temperature of the umbilical stump was 33.1±2.2°C at birth (1.5±1.6°C higher than the sternal reference temperature), and at 24±1 h of age the mean temperature of the umbilical stump was 33.0±4.3°C (0.5±1.8°C lower than the sternal reference temperature). These data suggest that these antiseptic compounds are equally effective for preventing infections and permitting healing of the umbilical cord when used within 30min of birth.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Bactérias/efeitos dos fármacos , Infecções Bacterianas/veterinária , Doenças dos Bovinos/prevenção & controle , Cordão Umbilical/efeitos dos fármacos , Cordão Umbilical/microbiologia , Animais , Infecções Bacterianas/etiologia , Infecções Bacterianas/microbiologia , Infecções Bacterianas/prevenção & controle , Bovinos , Doenças dos Bovinos/etiologia , Doenças dos Bovinos/microbiologia , Clorexidina/administração & dosagem , Citratos/administração & dosagem , Feminino , Iodo/administração & dosagem , Masculino
3.
J Dairy Sci ; 98(1): 595-601, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25465569

RESUMO

The objectives of this study were to (1) validate a method using refractometry to rapidly and accurately determine immunoglobulin (IgG) concentration in Jersey colostrum, (2) determine whether there should be different refractive index (nD) and %Brix cut points for Jersey colostrum, and (3) evaluate the effect of multiple freeze-thaw (FT) cycles on radial immunodiffusion (RID) and a digital refractometer to determine IgG concentration in Jersey colostrum. Samples (n=58; 3L) of colostrum were collected from a dairy in northwestern Iowa. Samples were analyzed within 2h of collection for IgG concentration by RID, %Brix, and nD by refractometer and an estimate of IgG by colostrometer. Samples were frozen, placed on dry ice, and transported to the laboratory at Iowa State University (Ames). Samples arrived frozen and were placed in a -20°C manual-defrost freezer until further analysis. On d 7 (1FT), d 14 (2FT), and 1yr (3FT) all samples were thawed, analyzed for IgG by RID, %Brix, nD by refractometer, and IgG estimate by colostrometer, and frozen until reanalysis at the next time point. Fresh colostrum had a mean (±SD) IgG concentration of 72.91 (±33.53) mg/mL, 21.24% (±4.43) Brix, and nD 1.3669 (±0.0074). Multiple FT cycles did affect IgG as determined by RID and colostrometer reading. The IgG concentrations were greater in fresh and 1FT samples as compared with 2FT and 3FT samples (72.91, 75.38, 67.20, and 67.31mg of IgG/mL, respectively). The colostrometer reading was lower in 1FT samples compared with fresh and 2FT samples. Multiple FT cycles had no effect on nD or %Brix reading. In fresh samples, IgG concentration was moderately correlated with nD (r=0.79), %Brix (r=0.79), and colostrometer reading (r=0.79). Diagnostic test characteristics using the recommended cut point of 1.35966 nD resulted in similar sensitivities for 1FT and 2 FT samples (94.87 and 94.74%, respectively). Cut points of 18 and 19% Brix resulted in the greatest sensitivities (92.31 and 84.62%) and specificity (94.74 and 94.74%, respectively). The 18% Brix cut point resulted in 94.83% of the samples being correctly classified based on IgG concentration. These data support the use of digital refractometer to accurately and rapidly determine IgG concentration in fresh Jersey colostrum. Additionally, these data suggest that IgG concentration determined by RID is affected by multiple FT cycles, whereas estimates obtained by refractometer are not affected by multiple FT cycles.


Assuntos
Bovinos/metabolismo , Colostro/química , Congelamento , Imunodifusão/veterinária , Imunoglobulina G/análise , Refratometria/veterinária , Animais , Feminino , Refratometria/instrumentação
4.
J Prev Alzheimers Dis ; 7(1): 37-42, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32010924

RESUMO

In 358 participants of the Tasmanian Healthy Brain Project, we quantified the cognitive consequences of engaging in varying loads of university-level education in later life, and investigated whether or not BDNF Val66Met affected outcomes. Assessment of neuropsychological, health, and psychosocial function was undertaken at baseline, 12-month, and 24-month follow-up. Education load was positively associated with change in language processing performance, but this effect did not reach statistical significance (P = 0.064). The BDNF Val66Met polymorphism significantly moderated the extent to which education load was associated with improved language processing (P = 0.026), with education load having a significant positive relationship with cognitive change in BDNF Met carriers but not in BDNF Val homozygotes. In older adults who carry BDNF Met, engaging in university-level education improves language processing performance in a load-dependent manner.


Assuntos
Envelhecimento/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Cognição , Polimorfismo Genético/genética , Desempenho Acadêmico , Idoso , Envelhecimento/fisiologia , Estudos de Casos e Controles , Disfunção Cognitiva/prevenção & controle , Humanos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tasmânia , Universidades
5.
Science ; 237(4812): 248-50, 1987 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-17772050

RESUMO

Although making liquid nitrogen-temperature superconductors is easy enough that high school science projects already feature them, researchers still have little idea how the new ceramic oxides work and therefore little guidance for improving them. At the International Workshop on Novel Mechanisms of Superconductivity, held from 22 to 26 June in Berkeley, California, theorists reviewed a host of competing explanations of how these materials come by their remarkable properties, but they could not, get far in sifting through the candidates for the best one. One cause of the unsettled situation is that theorists have not yet pushed their models far enough to make many specific predictions about physical properties and therefore to provide a reason to choose one theory over another. But experimental data for comparison with theory are lacking, too. For example, experimentalists are just now succeeding in being able to grow single crystals and thin films of the ceramic oxide superconductors, whose properties were shown at the workshop to be highly anisotropic. Measurements already made on the polycrystalline sintered material available up to now are difficult to interpret and therefore need to be repeated on good-quality crystals and films, where the variation of properties with crystallographic orientation can be mapped out. Given the high level of Japanese activity in the field, it was surprising that no researchers from industrial laboratories in Japan presented their findings at the workshop. In the light of a budding international competition in commercializing superconductors, some American scientists interpreted the absence as an attempt to protect proprietary advances. A more pleasant surprise was the attendance of a delegation of six Soviet scientists, although one of the fathers of superconductivity theory, Vitaly Ginzburg of the P.N.Lebedev Institute of Physics in Moscow, who was expected, did not come.

6.
Science ; 236(4798): 150-1, 1987 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-17789779

RESUMO

Last month in Washington, D.C., the National Academy of Sciences held the first of what it hopes will be a series of seminars in forefront fields of science, technology, and medicine. The idea is to bring the academy closer to the frontlines of research and to help spread the word to federal science policy-makers. The subject of the 23 and 24 March seminar was interfaces and thin films, and the talks, though tutorial in nature, contained a pleasantly large number of still unpublished results. Interfaces, such as the surface of a solid exposed to a liquid or gas, and thin films, whose properties are heavily influenced by interfaces, have long been of considerable technological importance and have always been so in biological processes, but researchers are now getting access to the experimental and theoretical tools needed to explore these complex physical systems that are neither ideally two-dimensional nor fully three-dimensional. The briefings that follow give a peek at three ways to probe interfaces involving liquids.

7.
Science ; 204(4400): 1396-8, 1979 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-17814188

RESUMO

The din in the packed arena had hardly subsided to a mild roar, when suddenly the fans exploded once again. "What a move!" screamed one nearby spectator. "How did he ever find a way through that defense?" wondered another, overcome with admiration.

8.
Med Trop (Mars) ; 68(2): 173-5, 2008 Apr.
Artigo em Francês | MEDLINE | ID: mdl-18630051

RESUMO

Cutaneous manifestation of tuberculosis is still observed in countries with high endemicity of tuberculosis such as Madagascar. The purpose of this report is to describe a case of nodular type cutaneous tuberculosis located in the subclavian region of a 5-month-old child living in Antananarivo, Madagascar. In absence of bacteriological evidence, diagnosis was based on epidemiological, clinical and histological findings. Treatment was successful using standard antituberculosis therapy. This case illustrates the diagnostic pitfalls associated with this type of tuberculosis.


Assuntos
Tuberculose Cutânea/diagnóstico , Antituberculosos/uso terapêutico , Quimioterapia Combinada , Granuloma de Células Gigantes/diagnóstico , Humanos , Lactente , Leucocitose/etiologia , Masculino , Tuberculose Cutânea/tratamento farmacológico
9.
Vaccine ; 36(47): 7198-7204, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-28958809

RESUMO

BACKGROUND: Rotavirus vaccine was introduced into the Extended Program on Immunization in Madagascar in May 2014. We analyzed trends in prevalence of all cause diarrhea and rotavirus hospitalization in children <5years of age before and after vaccine introduction and assessed trend of circulating rotavirus genotypes at Centre Hospitalier Universitaire Mère Enfant Tsaralalàna (CHU MET). METHODS: From January 2010 to December 2016, we reviewed the admission logbook to observe the rate of hospitalization caused by gastroenteritis among 19619 children <5years of age admitted at the hospital. In June 2013-December 2016, active rotavirus surveillance was also conducted at CHUMET with support from WHO. Rotavirus antigen was detected by EIA from stool specimen of children who are eligible for rotavirus gastroenteritis surveillance at sentinel site laboratory and rotavirus positive specimens were further genotyped at Regional Reference Laboratory by RT-PCR. RESULTS: Diarrhea hospitalizations decreased after rotavirus vaccine introduction. The median proportion of annual hospitalizations due to diarrhea was 26% (range: 31-22%) before vaccine introduction; the proportion was 25% the year of vaccine introduction, 17% in 2015 and 16% in 2016. Rotavirus positivity paralleled patterns observed in diarrhea. Before vaccine introduction, 56% of stool specimens tested positive for rotavirus; the percent positive was 13% in 2015, 12% in 2016. Diverse genotypes were detected in the pre-vaccine period; the most common were G3P[8] (n=53; 66%), G2P[4] (n=12; 15%), and G1P[8] (n=11; 14%). 6 distinct genotypes were found in 2015; the most common genotype was G2P[4] (n=10; 67%), the remaining, 5, G12[P8], G3[P8], G1G3[P4], G3G12[P4][P8] and G1G3[NT] had one positive specimen each. CONCLUSIONS: Following rotavirus vaccine introduction all-cause diarrhea and rotavirus-specific hospitalizations declined dramatically. The most common genotypes detected in the pre-vaccine period were G3P[8] and G2P[4] in 2015, the post vaccine period.


Assuntos
Diarreia/prevenção & controle , Gastroenterite/prevenção & controle , Hospitalização/estatística & dados numéricos , Programas de Imunização , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/uso terapêutico , Antígenos Virais/imunologia , Pré-Escolar , Diarreia/epidemiologia , Diarreia/virologia , Fezes/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Genótipo , Registros Hospitalares , Humanos , Lactente , Madagáscar/epidemiologia , Prevalência , Rotavirus/genética , Infecções por Rotavirus/epidemiologia , Vigilância de Evento Sentinela , Vacinação , Vacinas Atenuadas/uso terapêutico
10.
Sci Rep ; 7(1): 4926, 2017 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-28706240

RESUMO

Carbonaceous particulate matter (PM), comprising black carbon (BC), primary organic aerosol (POA) and secondary organic aerosol (SOA, from atmospheric aging of precursors), is a highly toxic vehicle exhaust component. Therefore, understanding vehicle pollution requires knowledge of both primary emissions, and how these emissions age in the atmosphere. We provide a systematic examination of carbonaceous PM emissions and parameterisation of SOA formation from modern diesel and gasoline cars at different temperatures (22, -7 °C) during controlled laboratory experiments. Carbonaceous PM emission and SOA formation is markedly higher from gasoline than diesel particle filter (DPF) and catalyst-equipped diesel cars, more so at -7 °C, contrasting with nitrogen oxides (NOX). Higher SOA formation from gasoline cars and primary emission reductions for diesels implies gasoline cars will increasingly dominate vehicular total carbonaceous PM, though older non-DPF-equipped diesels will continue to dominate the primary fraction for some time. Supported by state-of-the-art source apportionment of ambient fossil fuel derived PM, our results show that whether gasoline or diesel cars are more polluting depends on the pollutant in question, i.e. that diesel cars are not necessarily worse polluters than gasoline cars.

13.
Science ; 236(4802): 664, 1987 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-17748301
16.
Science ; 237(4815): 592, 1987 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-17758550
18.
Science ; 236(4797): 28, 1987 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-17759201
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