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1.
Phys Rev Lett ; 123(17): 171101, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31702251

RESUMO

Superradiance can trigger the formation of an ultralight boson cloud around a spinning black hole. Once formed, the boson cloud is expected to emit a nearly periodic, long-duration, gravitational-wave signal. For boson masses in the range (10^{-13}-10^{-11}) eV, and stellar mass black holes, such signals are potentially detectable by gravitational-wave detectors, like Advanced LIGO and Virgo. In this Letter, we present full band upper limits for a generic all-sky search for periodic gravitational waves in LIGO O2 data, and use them to derive-for the first time-direct constraints on the ultralight scalar boson field mass.

2.
Appetite ; 142: 104347, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31278956

RESUMO

Few children in the United States meet national fruit and vegetable intake recommendations, highlighting a need for interventions. Children's food preferences act as a barrier to fruit and vegetable consumption, but prior research has demonstrated that repeated taste exposures can increase children's acceptance of these foods. Prior research in this area has typically utilized controlled procedures in which children sample small tastes of target foods over repeated occasions. The primary aim of the present pilot study was to test whether children's preferences for target fruits and vegetables increased following repeated taste exposures to them through hands-on cooking in a community setting. Seventeen 6-to-8-year-old children participated in biweekly study sessions during six weeks of a summer camp serving lower-income families. Liking of (yummy, just OK, yucky) and rank-ordered preferences for nine fruits and vegetables were measured before and after exposure sessions (pre-test and post-test). Based on pre-test assessments, four relatively less liked foods (two fruits, two vegetables) were chosen to become target foods. Children were then exposed to target foods during nine hands-on cooking sessions; liking of target foods was also measured at a midpoint assessment. At each exposure session, children assisted with preparation of a different snack using a recipe involving target foods and then ate the prepared snack together. Preferences for target foods increased from pre-test (Median = 5.8) to post-test (Median = 5.5; p < 0.05). On average, the majority of children rated the prepared snacks favorably. Results from this pilot study demonstrate the potential of applying repeated exposure techniques via hands-on cooking in a community setting.


Assuntos
Culinária/métodos , Preferências Alimentares/psicologia , Frutas , Educação em Saúde/métodos , Promoção da Saúde/métodos , Verduras , Criança , Feminino , Assistência Alimentar , Humanos , Masculino , New York , Projetos Piloto , Pobreza , Recomendações Nutricionais , Lanches
3.
Obes Rev ; 19(4): 576-604, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29266778

RESUMO

The palatable, energy-dense foods that characterize modern environments can promote unhealthy eating habits, along with humans' predispositions to accept sweet tastes and reject those that are sour or bitter. Yet food preferences are malleable, and examining food preference learning during early life can highlight ways to promote acceptance of healthier foods. This narrative review describes research from the past 10 years focused on food preference learning from the prenatal period through early childhood (ages 2-5 years). Exposure to a variety of healthy foods from the start, including during the prenatal period, early milk-feeding and the introduction to complementary foods and beverages, can support subsequent acceptance of those foods. Yet development is plastic, and healthier food preferences can still be promoted after infancy. In early childhood, research supports starting with the simplest strategies, such as repeated exposure and modelling, reserving other strategies for use when needed to motivate the initial tasting necessary for repeated exposure effects to begin. This review can help caregivers and practitioners to promote the development of healthy food preferences early in life. Specific implementation recommendations, the role of individual differences and next steps for research in this area are also discussed.


Assuntos
Comportamento Alimentar/psicologia , Preferências Alimentares/psicologia , Promoção da Saúde , Poder Familiar , Desenvolvimento Infantil , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Ingestão de Alimentos , Comportamento Alimentar/fisiologia , Feminino , Humanos , Lactente , Recém-Nascido , Relações Pais-Filho , Gravidez
4.
Pediatr Obes ; 11(5): 333-48, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26842913

RESUMO

BACKGROUND: Breakfast consumption has been associated with reduced risk of overweight and obesity among children, but previous evidence reviews fail to confirm a causal relationship. OBJECTIVES: To review recent literature on breakfast consumption and adiposity among children and discuss potential underlying mechanisms. METHODS: A comprehensive literature search of studies published since the 2010 US National Evidence Library review (January 2010-January 2015) was conducted. RESULTS: Twelve studies met inclusion criteria. All were conducted in industrialized countries: six in Europe, four in the USA, one in China and one in Australia. Ten of the studies used observational longitudinal designs, with follow-up periods ranging from 1 to 27 years (median: 3, mean: 7.4); of these, eight reported inverse associations between breakfast consumption and excess adiposity, while two found no association. The other studies (1 case-control, 1 experimental) each reported a protective effect of breakfast consumption on overweight and obesity among children. CONCLUSIONS: Findings corroborate results from previous reviews, adding support for a possible, protective role for breakfast consumption in preventing excess adiposity during childhood and adolescence. However, drawing a causal conclusion from the collective evidence is curtailed by methodological limitations and inconsistencies, including study design, follow-up duration and frequency, exposure and outcome assessment, as well as limited consideration of confounding, mediating and effect-modifying variables. More rigorous study designs employing valid and standardized measurement of relevant variables are needed.


Assuntos
Adiposidade/fisiologia , Desjejum/fisiologia , Sobrepeso/prevenção & controle , Obesidade Infantil/prevenção & controle , Adolescente , Austrália , Índice de Massa Corporal , Criança , China , Europa (Continente) , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Estados Unidos
5.
Artigo em Inglês | MEDLINE | ID: mdl-25573031

RESUMO

In this study, we develop a two-dimensional finite element model, which is derived from an animal experiment and allows simulating osteogenesis within a porous titanium scaffold implanted in ewe's hemi-mandible during 12 weeks. The cell activity is described through diffusion equations and regulated by the stress state of the structure. We compare our model to (i) histological observations and (ii) experimental data obtained from a mechanical test done on sacrificed animal. We show that our mechano-biological approach provides consistent numerical results and constitutes a useful tool to predict osteogenesis pattern.


Assuntos
Modelos Biológicos , Osteogênese/efeitos dos fármacos , Alicerces Teciduais/química , Titânio/farmacologia , Animais , Difusão , Feminino , Análise de Elementos Finitos , Mandíbula/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Porosidade , Próteses e Implantes , Ovinos
6.
J Fish Dis ; 39(3): 353-66, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25939872

RESUMO

Lake trout Salvelinus namaycush (Walbaum) raised for stocking experienced yearly (2011-13) winter epizootics of epitheliocystis. Affected fish were dispersed on the bottom of the tank, had decreased feed and fright response, and mortality often reached 40%. Peak mortality occurred within 3 weeks of the appearance of clinical signs, and outbreaks typically lasted 6 weeks. Affected fish had no gross lesions but histologically had branchial epithelial necrosis and lamellar hyperplasia, with small to large numbers of scattered epithelial cells containing 10- to 20-µm inclusions. A longitudinal study was undertaken of one annual outbreak, and lamellar hyperplasia was most closely associated with mortality. The number of inclusions was statistically greater (P < 0.05) before and during peak mortality, but inclusions were present in low numbers before clinical signs occurred. Results of histochemical staining, immunohistochemistry and transmission electron microscopy supported the presence of a ß-proteobacteria rather than a Chlamydiales bacterium within inclusions. PCR primers to identify Chlamydiales did not give consistent results. However, the use of universal 16S rDNA bacterial primers in conjunction with laser capture microdissection of inclusions demonstrated that a ß-proteobacteria was consistently associated with affected gills and is more likely the cause of the disease in lake trout.


Assuntos
Epitélio/microbiologia , Doenças dos Peixes/microbiologia , Brânquias/microbiologia , Necrose/veterinária , Proteobactérias/fisiologia , Truta/microbiologia , Animais , Doenças dos Peixes/mortalidade , Doenças dos Peixes/patologia , Brânquias/patologia , Brânquias/ultraestrutura , Hiperplasia/microbiologia , Hiperplasia/mortalidade , Hiperplasia/patologia , Hiperplasia/veterinária , Imuno-Histoquímica , Estudos Longitudinais , Microscopia Eletrônica de Transmissão , Necrose/microbiologia , Necrose/mortalidade , Necrose/patologia , Proteobactérias/genética , RNA Ribossômico 16S/genética
7.
Med Mycol Case Rep ; 6: 42-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25379399

RESUMO

Purpureocillium lilacinum and Beauveria bassiana were isolated from lung sampled at necropsy of a 12 year-old female loggerhead sea turtle (Caretta caretta) that had displayed abnormal buoyancy. Histopathologic evaluation revealed pleuritis and pneumonia with non-melanized, septate hyphae and fruiting structures identical to those of P. lilacinum. This case emphasizes the importance of a histological correlate to fungal culture when environmental fungi are isolated and demonstrates the infrequent phenomenon of fruiting or conidial production in tissue.

8.
Vet Pathol ; 50(3): 368-76, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23528940

RESUMO

A retrospective study of the pathologic findings in weedy (Phyllopteryx taeniolatus) and leafy (Phycodurus eques) seadragons was performed on specimens submitted to 2 reference laboratories from 1994 to 2012 to determine the range and occurrence of diseases affecting aquarium-held populations. One hundred two and 94 total diagnoses were recorded in weedy and leafy seadragons, respectively. Two of the more common etiologic diagnoses in both species were mycobacteriosis and scuticociliatosis, whereas myxozoanosis was common in weedy seadragons. Metazoan parasite infections were less common etiologic diagnoses. There were no correlations between mycobacteriosis and ciliate protozoan infections in either species. Myxozoanosis was usually found in combination with other diseases and, except for 1 case, was restricted to weedy seadragons. Phaeohyphomycosis, nonmycobacterial bacterial infections, and trauma were also important but less frequent diagnoses. Intestinal coccidiosis was found in weedy but not leafy seadragons. Mineralization of the swim bladder was detected in 26 of 197 leafy seadragons and only 2 of 257 weedy seadragons. Although weedy and leafy seadragons share certain diseases of significance to exhibit populations, there are diseases unique to each species about which the veterinary pathologist, clinician, or diagnostician should be aware.


Assuntos
Infecções Bacterianas/veterinária , Doenças dos Peixes/patologia , Doenças Parasitárias em Animais/patologia , Feoifomicose/veterinária , Smegmamorpha , Sacos Aéreos/patologia , Animais , Infecções Bacterianas/patologia , Infecções por Cilióforos/patologia , Infecções por Cilióforos/veterinária , Coccidiose/patologia , Coccidiose/veterinária , Doenças dos Peixes/microbiologia , Doenças dos Peixes/parasitologia , Brânquias/patologia , Infecções por Mycobacterium não Tuberculosas/patologia , Infecções por Mycobacterium não Tuberculosas/veterinária , Oligoimenóforos/isolamento & purificação , Feoifomicose/patologia , Estudos Retrospectivos , Pele/patologia , Smegmamorpha/microbiologia , Smegmamorpha/parasitologia , Especificidade da Espécie
10.
Infect Immun ; 78(8): 3475-83, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20515935

RESUMO

Many lipoproteins are expressed on the surfaces of mycoplasmas, and some have been implicated as playing roles in pathogenesis. Family 2 lipoproteins of Mycoplasma pneumoniae have a conserved "mycoplasma lipoprotein X" central domain and a "mycoplasma lipoprotein 10" C-terminal domain and are differentially expressed in response to environmental conditions. Homologues of family 2 lipoproteins are Mycoplasma specific and include the lipoprotein of Mycoplasma gallisepticum, encoded by the MGA0674 gene. Comparative transcriptomic analysis of the M. gallisepticum live attenuated vaccine strain F and the virulent strain R(low), reported in this study, indicated that MGA0674 is one of several differentially expressed genes. The MGA0674-encoded lipoprotein is a proteolytically processed, immunogenic, TX-114 detergent-phase protein which appears to have antigenic divergence between field strains R(low) and S6. We examined the virulence of an R(low) Delta MGA0674 mutant (P1H9) in vivo and observed reduced recovery and attenuated virulence in the tracheas of experimentally infected chickens. The virulence of two additional R(low) Delta MGA0674 mutants, 2162 and 2204, was assessed in a second in vivo virulence experiment. These mutants exhibited partial to complete attenuation in vivo, but recovery was observed more frequently. Since only Mycoplasma species harbor homologues of MGA0674, the gene product has been renamed "Mycoplasma-specific lipoprotein A" (MslA). Collectively, these data indicate that MslA is an immunogenic lipoprotein exhibiting reduced expression in an attenuated strain and plays a role in M. gallisepticum virulence.


Assuntos
Proteínas de Bactérias/fisiologia , Lipoproteínas/fisiologia , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/patogenicidade , Doenças das Aves Domésticas/microbiologia , Fatores de Virulência/fisiologia , Animais , Proteínas de Bactérias/genética , Galinhas , Feminino , Deleção de Genes , Perfilação da Expressão Gênica , Lipoproteínas/deficiência , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/patologia , Doenças das Aves Domésticas/patologia , Traqueia/microbiologia , Traqueia/patologia , Virulência , Fatores de Virulência/deficiência
11.
Infect Immun ; 78(4): 1760-71, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20123709

RESUMO

Mycoplasma gallisepticum is a significant respiratory and reproductive pathogen of domestic poultry. While the complete genomic sequence of the virulent, low-passage M. gallisepticum strain R (R(low)) has been reported, genomic determinants responsible for differences in virulence and host range remain to be completely identified. Here, we utilize genome sequencing and microarray-based comparative genomic data to identify these genomic determinants of virulence and to elucidate genomic variability among strains of M. gallisepticum. Analysis of the high-passage, attenuated derivative of R(low), R(high), indicated that relatively few total genomic changes (64 loci) occurred, yet they are potentially responsible for the observed attenuation of this strain. In addition to previously characterized mutations in cytadherence-related proteins, changes included those in coding sequences of genes involved in sugar metabolism. Analyses of the genome of the M. gallisepticum vaccine strain F revealed numerous differences relative to strain R, including a highly divergent complement of vlhA surface lipoprotein genes, and at least 16 genes absent or significantly fragmented relative to strain R. Notably, an R(low) isogenic mutant in one of these genes (MGA_1107) caused significantly fewer severe tracheal lesions in the natural host compared to virulent M. gallisepticum R(low). Comparative genomic hybridizations indicated few genetic loci commonly affected in F and vaccine strains ts-11 and 6/85, which would correlate with proteins affecting strain R virulence. Together, these data provide novel insights into inter- and intrastrain M. gallisepticum genomic variability and the genetic basis of M. gallisepticum virulence.


Assuntos
DNA Bacteriano/genética , Genoma Bacteriano , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/genética , Mycoplasma gallisepticum/patogenicidade , Doenças das Aves Domésticas/microbiologia , Fatores de Virulência/genética , Animais , Galinhas , Hibridização Genômica Comparativa , DNA Bacteriano/química , Feminino , Dados de Sequência Molecular , Análise de Sequência de DNA
12.
Int J Pharm ; 380(1-2): 142-6, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19635538

RESUMO

In this study, we show that detoxifying W/O/W multiple emulsions, prepared with an appropriate extractant/trapping couple, represent a promising technology for quick and safe poisoning treatments, with application to the highly toxic herbicide Paraquat, responsible of poisonings from low-dose exposure leading to several deaths every year. In vitro tests led to the choice of an appropriate extractant/trapping couple system with significant detoxication performance. In vivo tests showed (i) that rats receiving high doses of Paraquat, then a detoxifying emulsion, presented an increase from 50% to 100% of the MST (median survival time) and (ii) that no mortality was observed during 30 days with rats dosed with emulsions initially loaded with Paraquat at a concentration much higher than the lethal dose, proving the stability and the inocuity of the detoxifying multiple emulsion in the gastrointestinal tract.


Assuntos
Emulsões/uso terapêutico , Paraquat/intoxicação , Desintoxicação por Sorção/métodos , Animais , Estabilidade de Medicamentos , Emulsões/síntese química , Herbicidas/intoxicação , Concentração de Íons de Hidrogênio , Masculino , Ratos , Ratos Wistar , Tensoativos , Taxa de Sobrevida
13.
Vet Pathol ; 46(2): 299-308, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19261643

RESUMO

Nocardia spp. infections in mammals cause pyogranulomatous lesions in a variety of organs, most typically the lung. Members of the Nocardia asteroides complex are the most frequently recognized pathogens. Nine cases of nocardiosis in free-ranging pinnipeds and 10 cases of nocardiosis in cetaceans were evaluated. Host species included the hooded seal (Cystophora cristata, n = 8), leopard seal (Hydrurga leptonyx, n = 1), Atlantic bottlenose dolphin (Tursiops truncatus, n = 4), beluga whale (Delphinapterus leucas, n = 4), and killer whale (Orcinus orca, n = 2). The most common presentation of nocardiosis in both pinnipeds and cetaceans was the systemic form, involving 2 or more organs. Organs most frequently affected were lung and thoracic lymph nodes in 7 of 9 cases in pinnipeds and 8 of 10 cases in cetaceans. Molecular identification and bacterial isolation demonstrated a variety of pathogenic species. N. asteroides, N. farcinica, N. brasiliensis, and N. otitisdiscaviarum are pathogenic for pinnipeds. In cetaceans N. asteroides, N. farcinica, N. brasiliensis, N. cyriacigeorgica, and N. levis are pathogenic. Hematoxylin and eosin and acid fast staining failed to reveal bacteria in every case, whereas modified acid fast and Grocott's methenamine silver consistently demonstrated the characteristic organisms. In both pinnipeds and cetaceans, juvenile animals were affected more often than adults. Hooded seals demonstrated more cases of nocardiosis than other pinnipeds.


Assuntos
Caniformia , Cetáceos , Nocardiose/veterinária , Nocardia/classificação , Nocardia/isolamento & purificação , Glândulas Suprarrenais/microbiologia , Glândulas Suprarrenais/patologia , Animais , Cerebelo/microbiologia , Cerebelo/patologia , Feminino , Pulmão/microbiologia , Pulmão/patologia , Linfonodos/microbiologia , Linfonodos/patologia , Masculino , Nocardiose/patologia , Pele/microbiologia , Pele/patologia , Vértebras Torácicas/microbiologia , Vértebras Torácicas/patologia
14.
Vaccine ; 26(16): 2010-9, 2008 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-18342996

RESUMO

In a previous study, signature sequence mutagenesis (SSM) was used to identify a mutant with a disruption of the gene encoding the metabolic factor, dihydrolipoamide dehydrogenase, and that mutant was designated Mg 7. The current study assessed the safety, immunogenicity and efficacy of Mg 7 in comparison to two commercially available vaccines (ts-11 and F) as well as a laboratory vaccine strain, GT5. Intratracheal vaccination of chickens with all four attenuated mutants induced varying levels of protection against intratracheal challenge with virulent Mycoplasma gallisepticum strain R(low). Mg 7 vaccinated chickens rapidly cleared the challenge strain, had lower histopathologic tracheal lesion scores when compared to unvaccinated chickens, and mounted a strong humoral anti-M. gallisepticum-specific IgG response. The IgG levels increased 2- to 3-fold upon R(low) challenge. Mg 7 induced a greater level of protection against intratracheal R(low) challenge than that observed with the other three attenuated strains, as evidenced by a lower recovery of R(low) from tracheas and lower histopathologic lesion scores in tracheas and air sacs. Based on these findings, Mg 7 appears to have good potential as a safe and effective vaccine for the prevention of avian mycoplasmosis.


Assuntos
Vacinas Bacterianas/administração & dosagem , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/imunologia , Doenças das Aves Domésticas/prevenção & controle , Infecções Respiratórias/veterinária , Vacinação , Sacos Aéreos/patologia , Animais , Anticorpos Antibacterianos/sangue , Galinhas , Di-Hidrolipoamida Desidrogenase/genética , Feminino , Mutação , Infecções por Mycoplasma/patologia , Infecções por Mycoplasma/prevenção & controle , Mycoplasma gallisepticum/enzimologia , Mycoplasma gallisepticum/genética , Doenças das Aves Domésticas/patologia , Mucosa Respiratória/patologia , Infecções Respiratórias/patologia , Infecções Respiratórias/prevenção & controle , Traqueia/patologia , Vacinas Atenuadas/administração & dosagem
15.
Infect Immun ; 74(2): 931-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16428737

RESUMO

To effectively analyze Mycoplasma gallisepticum for virulence-associated determinants, the ability to create stable genetic mutations is essential. Global M. gallisepticum mutagenesis is currently limited to the use of transposons. Using the gram-positive transposon Tn4001mod, a mutant library of 110 transformants was constructed and all insertion sites were mapped. To identify transposon insertion points, a unique primer directed outward from the end of Tn4001mod was used to sequence flanking genomic regions. By comparing sequences obtained in this manner to the annotated M. gallisepticum genome, the precise locations of transposon insertions were discerned. After determining the transposon insertion site for each mutant, unique reverse primers were synthesized based on the specific sequences, and PCR was performed. The resultant amplicons were used as unique Tn4001mod mutant identifiers. This procedure is referred to as signature sequence mutagenesis (SSM). SSM permits the comprehensive screening of the M. gallisepticum genome for the identification of novel virulence-associated determinants from a mixed mutant population. To this end, chickens were challenged with a pool of 27 unique Tn4001mod mutants. Two weeks postinfection, the birds were sacrificed, and organisms were recovered from respiratory tract tissues and screened for the presence or absence of various mutants. SSM is a negative-selection screening technique whereby those mutants possessing transposon insertions in genes essential for in vivo survival are not recovered from the host. We have identified a virulence-associated gene encoding dihydrolipoamide dehydrogenase (lpd). A transposon insertion in the middle of the coding sequence resulted in diminished biologic function and reduced virulence of the mutant designated Mg 7.


Assuntos
Elementos de DNA Transponíveis , Di-Hidrolipoamida Desidrogenase/genética , Mutagênese Insercional , Mycoplasma gallisepticum/patogenicidade , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/patologia , Animais , Proteínas de Bactérias , Galinhas/microbiologia , Di-Hidrolipoamida Desidrogenase/metabolismo , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/patologia , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/genética , Mycoplasma gallisepticum/metabolismo , Análise de Sequência de DNA , Organismos Livres de Patógenos Específicos , Virulência
16.
Infect Immun ; 70(12): 6839-45, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12438360

RESUMO

It was previously demonstrated that avirulent Mycoplasma gallisepticum strain R(high) (passage 164) is lacking three proteins that are expressed in its virulent progenitor, strain R(low) (passage 15). These proteins were identified as the cytadhesin molecule GapA, the putative cytadhesin-related molecule CrmA, and a component of a high-affinity transporter system, HatA. Complementation of R(high) with wild-type gapA restored expression in the transformant (GT5) but did not restore the cytadherence phenotype and maintained avirulence in chickens. These results suggested that CrmA might play an essential role in the M. gallisepticum cytadherence process. CrmA is encoded by the second gene in the gapA operon and shares significant sequence homology to the ORF6 gene of Mycoplasma pneumoniae, which has been shown to play an accessory role in the cytadherence process. Complementation of R(high) with wild-type crmA resulted in the transformant (SDCA) that lacked the cytadherence and virulence phenotype comparable to that found in R(high) and GT5. In contrast, complementation of R(high) with the entire wild-type gapA operon resulted in the transformant (GCA1) that restored cytadherence to the level found in wild-type R(low). In vivo pathogenesis trials revealed that GCA1 had regained virulence, causing airsacculitis in chickens. These results demonstrate that both GapA and CrmA are required for M. gallisepticum cytadherence and pathogenesis.


Assuntos
Adesinas Bacterianas/metabolismo , Aderência Bacteriana , Proteínas de Bactérias/metabolismo , Infecções por Mycoplasma/veterinária , Mycoplasma/patogenicidade , Doenças das Aves Domésticas/microbiologia , Animais , Proteínas de Bactérias/genética , Galinhas/microbiologia , Mycoplasma/fisiologia , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/fisiopatologia , Doenças das Aves Domésticas/fisiopatologia , Análise de Sequência de DNA , Transformação Bacteriana , Virulência
17.
Vaccine ; 20(31-32): 3709-19, 2002 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-12399199

RESUMO

The aim of this study was to assess the efficacy of a modified live Mycoplasma gallisepticum vaccine (GT5) for the protection of chickens against infection and respiratory disease. GT5 was constructed by the reconstitution of the avirulent high passage R (R(high)) strain with the gene encoding the major cytadhesin GapA. GT5 expressed GapA on its surface yet retained the phenotypic characteristics of the parental R(high) strain. Birds vaccinated with GT5 were protected upon challenge with the virulent low passage R (R(low)) strain as evidenced by a complete absence of tracheal lesions 2 and 4 weeks post-challenge, in contrast to sham immunized/challenged control birds. Modest amounts of IgG, and little, if any secretory IgA or IgM anti-M. gallisepticum were found in tracheal washings following vaccination. However, copious amounts of specific IgA were found following challenge, especially in sham immunized birds. This suggests that the tracheal IgG elicited by GT5 vaccination may have been responsible for blocking the initial colonization of R(low), thereby resulting in protection.


Assuntos
Vacinas Bacterianas/uso terapêutico , Infecções por Mycoplasma/prevenção & controle , Infecções por Mycoplasma/veterinária , Mycoplasma/imunologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Infecções Respiratórias/prevenção & controle , Infecções Respiratórias/veterinária , Vacinação/veterinária , Animais , Vacinas Bacterianas/administração & dosagem , Galinhas , Vias de Administração de Medicamentos/veterinária , Imunidade nas Mucosas , Imunoglobulina A Secretora/biossíntese , Imunoglobulina A Secretora/sangue , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Isotipos de Imunoglobulinas/biossíntese , Isotipos de Imunoglobulinas/sangue , Imunoglobulina M/biossíntese , Imunoglobulina M/sangue , Mycoplasma/isolamento & purificação , Infecções Respiratórias/microbiologia , Traqueia/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/uso terapêutico
18.
J Vet Diagn Invest ; 13(6): 524-30, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11724146

RESUMO

A 16-year-old female white whale, Delphinapterus leucas, died after nearly 18 months of chronic lymphopenia and pyogranulomatous dermatitis. Necropsy revealed rupture of the aorta with hemorrhage into the cranial mediastinum and between fascial planes of the ventral neck musculature. Multiple foci of ulcerative dermatitis and panniculitis were present across the thorax and abdomen and surrounded the genital folds. In addition, there was a chronic proliferative pleuritis with over 20 liters of histiocytic exudate in the thoracic cavity. Acid-fast bacteria consistent with Mycobacterium sp. were identified in sections of skin lesions and in cytospins of pleural exudate. Cultures of pleura and 1 skin lesion collected at necropsy yielded sparse growth of an acid-fast bacillus with colony characteristics and morphology consistent with Mycobacterium marinum. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis confirmed the presence of M. marinum DNA in samples of skin. This is the first documented occurrence of mycobacteriosis in a white whale and is a unique presentation of mycobacterial dermatitis and panniculitis with chronic pleuritis in a cetacean. The improved PCR-RFLP protocol utilized in this case unifies techniques from several protocols to differentiate between species of Nocardia and rapidly growing mycobacteria clinically relevant to aquatic animals.


Assuntos
Ruptura Aórtica/veterinária , Dermatite/veterinária , Infecções por Mycobacterium não Tuberculosas/veterinária , Mycobacterium marinum/isolamento & purificação , Paniculite/veterinária , Doenças Pleurais/veterinária , Baleias/microbiologia , Animais , Doença Crônica , DNA Bacteriano/análise , Dermatite/microbiologia , Evolução Fatal , Feminino , Infecções por Mycobacterium não Tuberculosas/complicações , Mycobacterium marinum/patogenicidade , Paniculite/microbiologia , Doenças Pleurais/microbiologia , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição
19.
J Parasitol ; 87(5): 972-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11695418

RESUMO

Gill lesions associated with infections of Erpocotyle tiburonis (Brooks, 1934) (Monogenea: Hexabothriidae) on wild bonnethead sharks (Sphyrna tiburo (L., 1758) (Carcharhiniformes: Sphyrinidae)) were compared with those on aquarium-held ones using light and scanning electron microscopy. Uninfected gill filaments had slender, triangular, smooth-surfaced lamellae and interlamellar water channels that were approximately equal in size. Four wild sharks were each infected by 3-11 widely separated adult E. tiburonis, and 1 of these sharks hosted a juvenile specimen. Lamellae flanking or touching adult E. tiburonis were pushed aside or bent, but were otherwise identical to those of uninfected filaments. Two aquarium-held sharks were each infected by hundreds of juvenile and adult E. tiburonis. In these sharks, lamellae near juveniles were pushed apart or bent, but were otherwise normal, whereas a thick, ragged-surfaced layer of hyperplastic epithelium both filled interlamellar water channels and partially or completely covered lamellae near adults. Results of this study suggest that the intense infections of E. tiburonis were facilitated by captivity and caused severe hyperplastic lesions that ultimately led to the death of the sharks by reducing or blocking the respiratory water flow over lamellae and thus reducing the exchange of gases and ions across the lamellar epithelium. In contrast, the wild sharks were infected by fewer worms and exhibited relatively minor lesions.


Assuntos
Doenças dos Peixes/parasitologia , Brânquias/parasitologia , Tubarões , Infecções por Trematódeos/veterinária , Animais , Feminino , Brânquias/ultraestrutura , Microscopia Eletrônica de Varredura , Trematódeos/anatomia & histologia , Trematódeos/ultraestrutura , Infecções por Trematódeos/parasitologia
20.
Neurol Sci ; 22(1): 89-91, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11487216

RESUMO

We report that the area under the curve of L-dopa plasma concentration, following the administration of a single 250 mg L-dopa dose, is augmented after Helicobacter pylori (HP) eradication in six Parkinson's disease (PD) patients showing high IgG antibody titer against HP. A prolongation of L-dopa clinical benefit was also observed. We suggest that HP infection-activated gastric alterations may be responsible, at least in part, for the reported erratic efficacy of oral L-dopa therapy in some advanced PD patients. Given the high percentage of HP-positivity in the age cohorts including the largest prevalence of PD patients, we propose that HP eradication be recommended in all PD patients under L-dopa therapy.


Assuntos
Antiparkinsonianos/sangue , Infecções por Helicobacter/fisiopatologia , Helicobacter pylori/patogenicidade , Levodopa/sangue , Síndromes de Malabsorção/fisiopatologia , Doença de Parkinson/tratamento farmacológico , Idoso , Antiparkinsonianos/uso terapêutico , Área Sob a Curva , Humanos , Levodopa/uso terapêutico , Síndromes de Malabsorção/microbiologia , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia
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