RESUMO
PURPOSE OF THE REVIEW: The aim of this review is to discuss recent data pointing at an involvement of human endogenous retroviruses (HERVs) in type 1 diabetes (T1D) onset and progression. RECENT FINDINGS: The envelope protein of HERV-W family, named HERV-W-Env, was detected in pancreata from T1D patients and was shown to display pro-inflammatory properties and direct toxicity toward pancreatic beta cells. The etiopathogenesis of T1D remains elusive, even if conventional environmental viral infections have been recurrently involved. Nonetheless, a new category of pathogens may provide the missing link between genetic susceptibility and environmental factors long thought to contribute to T1D onset. A number of studies have now shown that HERV sequences, which are normally inactivated or repressed in the human genome, could be activated by environmental viruses. Thus, if similarly activated by viruses associated with T1D, disregarded HERV genes may underlie T1D genetic susceptibility. Moreover, once expressed, HERV elements may display broad pathogenic properties, which identify them as potential new therapeutic targets.
Assuntos
Diabetes Mellitus Tipo 1/etiologia , Retrovirus Endógenos/fisiologia , Produtos do Gene env/isolamento & purificação , Células Secretoras de Insulina/virologia , Ativação Viral/fisiologia , Animais , Doenças Autoimunes/etiologia , Doenças Autoimunes/fisiopatologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/virologia , Modelos Animais de Doenças , Progressão da Doença , Retrovirus Endógenos/isolamento & purificação , Retrovirus Endógenos/patogenicidade , Epigênese Genética , Interação Gene-Ambiente , Humanos , CamundongosRESUMO
Feces-based population genetic studies have become increasingly popular. However, polymerase chain reaction (PCR) amplification rates from fecal material vary depending on the species, populations, loci, and extraction protocols. Here, we assessed the PCR amplification success of three microsatellite markers and a segment of the mitochondrial control region of DNA extracted from field-collected feces of guanaco (Lama guanicoe) using two protocols - Qiagen DNA Stool Kit and 2 cetyltrimethylammonium bromide/phenol:chloroform:isoamyl alcohol (2CTAB/PCI) method. Chelex resin treatment to remove inhibitors was also tested. Our results show that the mitochondrial locus was the most difficult to amplify. PCR success rates improved for all markers after Chelex treatment of extracted DNA, and 2CTAB/PCI method (95.83%) appeared to perform slightly better than stool kit (91.67%) for the nuclear markers. Amplification success was significantly influenced by the extraction method, Chelex treatment, and locus (P < 0.001) but not by the freshness of the feces (fresh vs old, P = 0.17). The repeatability levels were high without Chelex treatment (> 0.89), but they decreased slightly after treatment for amplification of nuclear markers and markedly after treatment for amplification of the mitochondrial control region. Thus, we showed that Chelex treatment gives high PCR success, especially for nuclear markers, and adequate DNA extraction rates can be achieved from L. guanicoe feces even from non-fresh fecal material. Although not significant, 2CTAB/PCI method tended to provide higher successful amplification rates on a whole set of samples, suggesting that the method could be particularly useful when using small sample sizes.
Assuntos
Camelídeos Americanos/genética , DNA/isolamento & purificação , Fezes/química , Animais , DNA/genética , Loci Gênicos , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos TestesRESUMO
We present temperature-dependent single-crystal diffraction results on seven antifluorite-typeA2MeX6compounds withMe= Os or Ir: K2OsCl6,A2OsBr6withA= K, Rb, Cs and NH4, and K2IrX6withX= Cl and Br. The structural transitions in this family arise fromMeX6octahedron rotations that generate a rich variety of symmetries depending on the rotation axis and stacking schemes. In order to search for local distortions in the high-symmetry phase we perform refinements of anharmonic atomic displacement parameters with comprehensive data sets. Even at temperatures close to the onset of structural distortions, these refinements only yield a small improvement indicating only small anharmonic effects. The phase transitions in these antifluorites are essentially of displacive character. However, some harmonic displacement parameters are very large reflecting soft phonon modes with the softening covering large parts of the Brillouin zone. The occurrence of the rotational transitions in the antifluorite-type family can be remarkably well analyzed in terms of a tolerance factor of ionic radii.
RESUMO
The ease of prescribing radiological examinations has prompted an expansion in radiological procedures and, consequently, an increase of occupational dose to medical imaging workers. However, little is known about radiation exposure in the workplace of medical radiology professionals in many countries, and in Benin particularly. The purpose of this study was to assess ambient radiation doses in diagnostic X-ray medical facilities in Benin and to observe whether exposure levels are below reference levels. A total of 72 public and private medical imaging centres participated in a cross-sectional study carried out from June 2019 to February 2020 in Benin. These centres had 59 X-ray, four chest and six computed tomography (CT) scan rooms. A calibrated radiameter able to measure short, pulsed or continuous X fields and gamma/beta (50 nSv to 10 Sv) was used to measure exposure levels in these functional rooms. Scattered X-ray doses and exposure time from radiological examinations both behind the lead glass of the control area to assess the levels of exposure of professionals and outside of the examination room to evaluate the level of exposure of the public (including non-exposed workers) have been provided. Equivalent doses estimated per hour were compared with the reference levels of 7.50 and 0.05 µSv per hour for workers and the public, respectively. At the control area, the mean/median (min-max) equivalent doses were 0.09/0.07 (0.00-0.21), 2.39/0.13 (0.00-75.67), and 228.39/28.65 (0.39-869.75) µSv per hour for the chest, X-ray, and CT-scan rooms, respectively. Among 69 examination rooms, 13.04% of the equivalent dose estimated in the workplace behind the lead glass was greater than 7.50 µSv per hour; 65 out of 69 examination rooms showed that 40.00% of the equivalent dose estimated behind the doors was greater than 0.05 µSv per hour. These results demonstrated that current controls, including leaded glass separating the control panel and leaded doors between the examination room and the corridor, are inadequate to limit radiation exposures. The controls must be upgraded and a dosimetry program should be implemented to monitor exposures of employees, patients, and visitors.
Assuntos
Exposição Ocupacional , Exposição à Radiação , Benin , Estudos Transversais , Humanos , Exposição Ocupacional/análise , Doses de Radiação , Radiografia , Local de TrabalhoRESUMO
The present study examined in lambs whether exposure to flavors derived from pregnant mother's diet and transferred to amniotic fluid (AF) could induce a preference for artificial milk containing one of these flavors. To test this hypothesis, cumin was added to the maternal diet in the last month of gestation. Preference for artificial milk containing p-cymene, one of the chemosensory compounds of cumin, was tested within the first two days after birth in maternally deprived lambs born from mothers fed a cumin-flavored diet (Cumin group), or an unflavored diet (Control group). Aromatic profile of AF from cumin-fed mothers was analyzed by GC-MS/MS to determine whether p-cymene could be detected. While the control group avoided the flavored artificial milk on day 1, the Cumin group did not and showed a preference for the cumin-scented formula on day 2. GC-MS/MS profile of AF revealed that four of the main volatile cumin compounds, p-cymene, p-cymenene, ß-pinene and γ-terpinene were present in variable amounts in all samples, p-cymene being the most frequently detected. These findings indicate that newborn lambs can memorize flavors from the mother's diet present in AF and that prenatal experience influences their preference for an artificial milk containing one specific flavor.
Assuntos
Preferências Alimentares , Leite , Líquido Amniótico , Animais , Animais Recém-Nascidos , Dieta , Feminino , Gravidez , Ovinos , Espectrometria de Massas em TandemRESUMO
Temperature is an important climate factor that has a direct influence on insect biology and consequently a crucial role in forecasting and integrated pest management. The mealybug Dysmicoccus brevipes (Cockerell) (Hemiptera: Pseudococcidae) is one of the most common species in Brazilian vineyards. Here, development and survival of D. brevipes on leaves of table grapes (Vitis vinifera cv. Itália) were studied at five constant temperatures (15, 20, 25, 28, and 30 ± 1°C) under laboratory conditions. We investigated the developmental time and nymphal survival, temperature thresholds, and the degree-day requirements for each life stage of D. brevipes. The developmental time for the nymphal stage ranged from 32 to 130 days with decreasing the temperature, with the temperatures of 28 and 30°C providing the shorter developmental time. Survival of the entire nymphal stage was affected by the temperature, ranging from 81% at 20°C to 1% at 15°C. The predicted upper lethal temperature was 34.5°C, while the optimal temperature was 28.6°C. The minimum threshold for total development of D. brevipes occurred at 8.2°C. Dysmicoccus brevipes required 678.4 degree-days to complete development from first-instar nymph to adult. The temperature of 30°C was the most suitable for the development of D. brevipes. The thermal thresholds estimated for D. brevipes life cycle suggest that this species can develop in different table grape-producing regions of Brazil, in a temperature range between 8 and 35°C.
Assuntos
Hemípteros/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Temperatura , Vitis , Animais , Brasil , Feminino , Frutas , Controle de PragasRESUMO
INTRODUCTION: Myeloid sarcomas are uncommon proliferations of immature myeloid cells occurring in any extramedullary organ. We report here two cases of myeloid sarcomas in patients with, respectively, a polycythemia vera and a myelodysplastic syndrome. CASE REPORTS: The first is an 81-year-old woman who presented with osteolytic lesions. Diagnosis has been highlighted using anatomopathological study after bone marrow biopsy, but it was delayed because of a very localized basin lesion and few positive myeloid markers. The second patient is an 86-year-old man who presented with pancytopenia and several lymph nodes. Lymph node cytology failed because of the rarity of blast cells. Diagnosis was done after anatomopathological study on lymph node biopsy which revealed a localized form of myeloid sarcoma. CONCLUSION: The diagnosis of myeloid sarcoma must be considered when unusual tumors occur in patients with a chronic myeloid disease. In that case, therapeutic options are those of an acute myeloid leukemia.
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Sarcoma Mieloide/diagnóstico , Idoso de 80 Anos ou mais , Biópsia , Medula Óssea/patologia , Diagnóstico Diferencial , Feminino , Humanos , Leucemia Mieloide Aguda/diagnóstico , Masculino , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/diagnóstico , Sarcoma Mieloide/etiologiaRESUMO
In beet distilleries, condensates arising from stillage concentration could be recycled as dilution water for the fermentation step, thus preserving groundwater resources and ensuring a quality-controlled water supply. However, the recycling of condensates has been found to cause a significant reduction in fermentation activity. This study aimed to verify that condensates are toxic to alcoholic fermentation. Ten compounds found in condensates (formic, acetic, propionic, butyric, valeric, and hexanoic acids; 2,3-butanediol, furfuryl alcohol, furfural, and 2-phenyl-ethyl-alcohol) were tested. With the exception of 2,3-butanediol, they all proved to be inhibitors. At the same molar concentration, the longer the carbonaceous chain, the stronger the inhibition by fatty acids. An experimental design was used to study the inhibitory characteristics of the 10 compounds at the concentrations found in condensates. Synergistic effects were also confirmed. In real effluents, acetic acid was so highly concentrated that it became the strongest inhibitor. It is therefore necessary to eliminate it before recycling, as well as less concentrated compounds that may accumulate, as illustrated by the simulation.
Assuntos
Álcoois/metabolismo , Conservação dos Recursos Naturais , Fermentação , Microbiologia de Alimentos , Ácidos Acíclicos/farmacologia , Butileno Glicóis/farmacologia , Ácidos Graxos/farmacologia , Furaldeído/farmacologia , Furanos/farmacologia , Álcool Feniletílico/farmacologia , Fatores de TempoRESUMO
OBJECTIVE: To assess the awareness and attitude towards AIDS and PLHA in slum dwellers of Chennai, an Indian metropolis by KAP (Knowledge, Attitude, Practice) study. METHODS: A cross sectional study was conducted in a representative sample of 650 subjects (400 females and 250 females), aged 15-45 years, by means of a questionnaire in the local dialect Tamil. RESULTS: The overall literacy rate was 64%, with males being 70% and females being 60% literate. 20% of males and 11% of females do not know about a disease called AIDS. Only 67% of males and 55% of females are aware of the sexual mode of transmission. 34% of males and 50% females opine that AIDS is also a hereditary disease. Also 45% of males and 62% of females feel that AIDS also spreads by air, fomites, or mosquito-bite. Only 30% of males and 22% females know about the possible symptoms of AIDS. 30% of males and 45% of females never ask for a new syringe if not provided, as they are totally unaware of its significance. 43% of males and 78% of females do not know about the risk of a barber's blade. 56% of males and 71% of females feel that AIDS can be treated at least by a traditional medicine. Lastly, 48% of males and 60% females prefer outcasting an AIDS patient from the slum. CONCLUSIONS: AIDS awareness in the slum dwellers of Chennai is very poor. Corresponding awareness in suburbs and rural areas will be much worse. Conventional IEC methods targeting general population via mass media are not reaching the slum dwellers, even in a metropolitan city. A specially designed targeted intervention is needed.
Assuntos
Síndrome da Imunodeficiência Adquirida/psicologia , Atitude Frente a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Áreas de Pobreza , População Urbana , Síndrome da Imunodeficiência Adquirida/transmissão , Adolescente , Adulto , Barbearia , Estudos Transversais , Escolaridade , Feminino , Educação em Saúde , Medicina Herbária , Humanos , Índia , Masculino , Medicina Tradicional , Pessoa de Meia-Idade , Fatores de Risco , SeringasRESUMO
Septins are highly conserved and essential eukaryotic cytoskeletal proteins that interact with the inner plasma membrane. They are involved in essential functions requiring cell membrane remodeling and compartmentalization, such as cell division and dendrite morphogenesis, and have been implicated in numerous diseases. Depending on the organisms and on the type of tissue, a specific set of septins genes are expressed, ranging from 2 to 13. Septins self-assemble into linear, symmetric rods that can further organize into linear filaments several microns in length. Only a subset of human septins has been described at high resolution by X-ray crystallography (Sirajuddin et al., 2007). Electron microscopy (EM) has proven to be a method of choice for analyzing the molecular organization of septins. It is possible to localize each septin subunit within the rod complex using genetic tags, such as maltose-binding protein or green fluorescent protein, to generate a visible label of a specific septin subunit in EM images that are processed using single-particle EM methodology. In this chapter we present, in detail, the methods that we have used to analyze the molecular organization of budding yeast septins (Bertin et al., 2008). These methods include purification of septin complexes, sample preparation for EM, and image processing procedures. Such methods can be generalized to analyze the organization of septins from any organism.
Assuntos
Citoesqueleto/ultraestrutura , Microscopia Eletrônica/métodos , Complexos Multiproteicos/isolamento & purificação , Proteínas Recombinantes/isolamento & purificação , Septinas/isolamento & purificação , Cristalografia por Raios X , Citoesqueleto/química , Proteínas de Fluorescência Verde , Complexos Multiproteicos/química , Complexos Multiproteicos/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/ultraestrutura , Septinas/química , Septinas/genéticaRESUMO
OBJECTIVE: This study has been carried out to assess the effect of tobacco smoking and of betel quid chewing with tobacco on buccal mucosa by cytomorphometry, in a south Indian population. STUDY DESIGN: Cellular diameter (CD) and nuclear diameter (ND) of exfoliated buccal squames obtained from clinically normal appearing buccal mucosa of tobacco smokers, betel quid with tobacco chewers, and those with a combined habit, stained by the Papanicolaou method, were measured. Non-users served as negative controls and oral squamous cell carcinomas in tobacco users served as positive controls. One way ANOVA test of the values obtained followed by multiple range comparison with Tukey-HSD procedure (at p=0.05) was carried out. RESULTS: A statistically significant reduction in CD and increase in ND in smokers and those with a combined habit were observed. CONCLUSION: The use of tobacco in the form of smoking influences the cytomorphology of buccal mucosa.
Assuntos
Mucosa Bucal/patologia , Fumar/patologia , Areca/efeitos adversos , Carcinoma de Células Escamosas/patologia , Núcleo Celular/ultraestrutura , Tamanho Celular , Corantes , Técnicas Citológicas , Células Epiteliais/patologia , Feminino , Humanos , Masculino , Neoplasias Bucais/patologia , Fumar/efeitos adversos , Tabaco sem Fumaça/efeitos adversosRESUMO
Enterotoxigenic Escherichia coli (ETEC) strain P2200 of porcine origin possessed eight possibly plasmid-determined characters (K88+ Raf+ Hly+ Col+ Smr Tcr Su(r) STa+) and six plasmid DNA bands of 4.2-93 kb. Analysis of the spontaneous loss of characters and the results of matings with other E. coli strains revealed that the K88, Raf, Hly, Smr, Tcr and Su(r) characters could be transferred, and that the presence of the K88 and Raf characters was associated with an 83-kb plasmid. The presence and location of the STaI gene was investigated in several ETEC strains of bovine or porcine origin. Hybridisation with a non-radioactive polynucleotide probe associated the STaI gene with a plasmid in each strain; these plasmids were of 32-142 kb. In contrast, plasmids from a P2200 STa- variant and plasmids from two STa- variants of the bovine ETEC strain B41* (strain B41 obtained from a different source) did not hybridise with the probe. One of the B41*STa- variants had lost the STa plasmid, whereas the second variant retained a plasmid of the same size which did not hybridise. In contrast, a third B41*STa- variant retained a plasmid of the same size that still hybridised with the STaI probe. Plasmid DNA restriction fragment analysis, followed by hybridisation with the STaI probe, showed that the STaI gene was associated with 8.3-, 6.8- and 3.5-kb plasmid fragments in strain B41, and with 4.9-, 6.8- and 3.5-kb plasmid fragments in strain B41*, following digestion with EcoRI, BamHI, or EcoRI + BamHI, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Toxinas Bacterianas/genética , Escherichia coli/genética , Genes Bacterianos/genética , Plasmídeos/genética , Animais , Southern Blotting , Sondas de DNA , DNA Bacteriano/análise , Enterotoxinas/genética , Hibridização de Ácido Nucleico , Mapeamento por Restrição , SuínosRESUMO
Infant mice from outbred Swiss OF1 and from inbred DBA/2, C57BL/6, BALB/cBy and CBA strains were screened for usefulness in the diarrhoea model with enterotoxigenic Escherichia coli (ETEC) strains of bovine, porcine and human origin. Mouse strains were either weakly susceptible or not susceptible to ETEC strains of porcine or human origin bearing antigen K88, 987P, CFA/I or CFA/II. In contrast, some mouse strains were highly susceptible to bovine and porcine ETEC strains bearing K99 or F41 or both antigens. Swiss OF1 and CBA infant mice were highly susceptible to one bovine ETEC strain bearing antigen K99, whereas DBA/2, BALB/cBy and C57BL/6 mice exhibited nearly complete resistance to the same ETEC strain. Except DBA/2, all mouse strains were highly susceptible to bovine and porcine ETEC strains bearing antigen F41 alone or in combination with antigen K99. Challenge ETEC strains colonised intestines of all infant mice, but they reached very high levels soon after inoculation in the diarrhoeic ones only.
Assuntos
Escherichia coli/patogenicidade , Intestinos/microbiologia , Animais , Bovinos , Enterotoxinas , Escherichia coli/imunologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Endogâmicos DBA , Especificidade da Espécie , Suínos , VirulênciaRESUMO
Rats and mice when forced to swim in a restricted space will rapidly cease attempts to escape and become immobile. Previous experiments have shown that immobility was selectively reduced by antidepressant agents. The present experiments show that important differences exist between strains in both the amount of immobility observed and the effects of imipramine. Strain differences should therefore be taken into account in attempts to replicate results from one laboratory to another.
Assuntos
Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Imipramina/farmacologia , Animais , Depressão/psicologia , Humanos , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Ratos , Especificidade da Espécie , NataçãoRESUMO
Rats were forced to swim in a restricted space will rapidly cease apparent attempts to escape and adopt a characteristic posture which we have termed "immobility". We show in previous experiments that immobility was reduced by a variety of antidepressant agents and thus suggested that the method could serve as a screening model for antidepressants. The present experiments showed that immobility was reduced by drugs which increase central dopaminergic and alpha-adrenergic activity but was less affected by drugs which act mainly on central serotonin. Conversely, immobility could be increased by drugs which diminish central catecholamine activity but not by drugs which inhibit central serotonin. It was concluded that immobility depended primarily on the activity of central catecholamines but that caution was required before ascribing immobility exclusively to activity within a single system.
Assuntos
Química Encefálica/efeitos dos fármacos , Catecolaminas/fisiologia , Atividade Motora/efeitos dos fármacos , Serotonina/fisiologia , Natação , Animais , Dopamina/fisiologia , Masculino , Inibidores da Monoaminoxidase/farmacologia , Norepinefrina/fisiologia , Ratos , Receptores Adrenérgicos/efeitos dos fármacos , Receptores Dopaminérgicos/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacosRESUMO
F41-positive and F41-negative derivatives of bovine enterotoxigenic Escherichia coli strain B41 carrying K88 or K88 and K99 plasmids were investigated for stability and expression of genes for their fimbrial antigens. Either K88 plasmid alone or both K88 and K99 plasmids could be maintained in these strains though stability could depend on culture medium. K99 antigen could be detected in each strain bearing K99 plasmid. Clones that produced K88 antigen or clones that did not produce this antigen could be isolated from each strain, except from the strain that possessed K99 plasmid in the strain that did not possess the ability to produce F41 antigen. Strains possessing K88 plasmid in the strain able to produce F41 antigen produced clones expressing either both K88 and F41 antigens, (also F41 appeared strongly expressed in some clones) or clones that produced only F41 antigen or no antigen at all. Clones that produced only K88 antigen or others that did not produce this antigen could be produced from a strain bearing only K88 plasmid and that did not possess the ability to produce F41 antigen. None of these strains bearing K88 plasmid alone or additionally K99 plasmid produced mannose-resistant hemagglutination of horse or sheep erythrocytes at 20 degrees C as found for K99 and F41 ETEC natural strains, respectively. These results suggested that the structures of pili when several genetic determinants were present simultaneously may not be identical to those of original strains. In this study, clones expressing either one, two or three adhesin bearing antigens could be obtained from the strain B41.
Assuntos
Adesinas de Escherichia coli/biossíntese , Antígenos de Bactérias , Antígenos de Superfície/biossíntese , Proteínas da Membrana Bacteriana Externa/biossíntese , Toxinas Bacterianas , Proteínas de Escherichia coli , Escherichia coli/imunologia , Proteínas de Fímbrias , Adesinas de Escherichia coli/genética , Animais , Especificidade de Anticorpos , Antígenos de Superfície/genética , Proteínas da Membrana Bacteriana Externa/genética , Bovinos , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Genótipo , Cobaias , Testes de Hemaglutinação/veterinária , Cavalos , Immunoblotting/veterinária , Fenótipo , Plasmídeos , Ovinos , SuínosRESUMO
In vitro adherence to intestinal epithelial cells by enterotoxigenic Escherichia coli strains bearing K88, K99, F41, or 987P adhesins and of their variants not bearing adhesins (K88-, K99-, or F41-) was investigated in European Large White and Chinese Meishan pigs. Possible relationship between adherence and virulence was also examined. The K88-positive (K88+) strain strongly adhered to intestinal epithelial cells from 26 of 28 Large White pigs. This strain had previously been found to be highly virulent for Large White pigs. The only surviving pig was of nonadherent phenotype, and cells from 4 dehydrated moribund pigs had strong adherence. By contrast, the same K88+ strain found previously to have little pathogenicity for Meishan pigs adhered with variable intensity to cells from 17 of 23 Meishan pigs; correlation was not evident between adherence and virulence. The K99+ F41+ strain of porcine origin and the F41+ strain generally adhered strongly to cells from 24 and 23 Meishan pigs, respectively, and to cells from 25 of 26 Large White pigs. Correlation was not found between adherence and virulence for the 2 strains. A K99+ F41+ strain of bovine origin adhered to cells from 20 of 22 Meishan and 22 of 23 Large White pigs, and a K99- F41+ variant adhered to cells from 19 of 23 Meishan and 23 of 24 Large White pigs. The adhesin-negative variants never adhered to intestinal epithelial cells. Strain 987 known not to readily produce 987P adhesin after in vitro growth never adhered to cells during the test.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Aderência Bacteriana , Escherichia coli/patogenicidade , Intestinos/microbiologia , Suínos , Animais , Epitélio/microbiologia , Escherichia coli/classificação , Especificidade da Espécie , Virulência/fisiologiaRESUMO
Conventionally raised Chinese Meishan and European Large White pigs were intragastrically challenge exposed with 2.1 x 10(10) enterotoxigenic Escherichia coli strains bearing colonization factor K88, 987P, F41, or F41 plus K99. In response to challenge exposure with the K88-positive (K88+) organisms, 96% of Large White pigs died within 48 hours, whereas none of the Meishan pigs died. Both breeds of pigs had similar susceptibility to strains bearing 987P or F41. Lastly, Meishan pigs were found to be more susceptible than Large White pigs to a strain expressing K99 and F41. In pigs with diarrhea, challenge-exposure strains intensively colonized the jejunum (10(8) to 10(10) bacteria/g of tissue) and, to less extent, the duodenum (except K88+ strain, which comprised 10(8)/g). In most cases, jejunal concentrations of the challenge-exposure strains were substantially lower in pigs that did not have diarrhea. Half the resistant Meishan pigs eliminated the K88+ strain from the intestines. Colostral antibody titer that agglutinated challenge-exposure strains did not differ between Meishan and Large White gilts. Results indicate that resistance of pigs to the K88+ strain did not extend to enterotoxigenic strains bearing other well-known factors. They indicate, in addition, that genetic resistance to K88+ strains described in pigs in Europe may exist in pigs in China.
Assuntos
Diarreia/veterinária , Infecções por Escherichia coli/veterinária , Escherichia coli/patogenicidade , Proteínas de Fímbrias , Suínos , Animais , Antígenos de Bactérias/imunologia , Aderência Bacteriana/fisiologia , Proteínas de Bactérias/imunologia , Diarreia/etiologia , Suscetibilidade a Doenças , Escherichia coli/classificação , Infecções por Escherichia coli/etiologia , Feminino , Gravidez , Especificidade da Espécie , VirulênciaRESUMO
The goal of this randomized, double blind and multicentric study was to compare the effects of midazolam (M) and placebo (P) administered by titration before puncture for spinal anaesthesia on the comfort of 211 patients scheduled for elective surgery after oral premedication with hydroxyzine. The administered dose of midazolam was 3.4 +/- 1.3 mg (mean +/- SD). Anxiety was nil in 92% of the patients of the M group and in 64% of the patients of the P group (p < 0.001) and memorization of the pain of the puncture was reported in 34% of the patients of the M group and in 66% of the patients of the P group (p < 0.001). However cooperation of the patient and easiness of the puncture were similar in both groups. In conclusion titrated sedation with midazolam before puncture for spinal anaesthesia increases the comfort of the patient.
Assuntos
Adjuvantes Anestésicos , Raquianestesia , Hipnóticos e Sedativos , Midazolam , Adulto , Idoso , Ansiedade/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , PlacebosRESUMO
This study tested whether lines of Japanese quails divergently selected for a fear response, the tonic immobility, might constitute a reliable bird model for studying anxiety. Previous studies demonstrated that the selection modifies the general underlying emotionality of the birds rather than exerting its effect only on tonic immobility. The behavioural effects of intraperitoneal injections of diazepam, an anxiolytic drug, were assessed in two lines of quail selected either for their short (STI) or long (LTI) duration of tonic immobility. Effects of diazepam were examined in two tests used for measuring emotionality in birds, the open field and the tonic immobility tests. After being placed in the centre of the open field, birds with a high emotionality (LTI quails) stayed longer in the centre of the apparatus than STI quail. Diazepam had anxiolytic effect in LTI birds as it increased the time spent in the outer area. This effect of diazepam appears to be selective because the drug has no effect on other behaviours such as distress calls or escape attempts. The drug has also no effect on the tonic immobility response in any of the two lines. These findings reveal an "anxiogenic" trait of LTI birds in the open field test that can be modulated by the administration of an anxiolytic drug. Therefore quails selected for LTI and STI represent a valuable model to study the mechanisms underlying anxiety in birds.