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1.
Open Vet J ; 14(6): 1313-1329, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39055762

RESUMO

Salmonellosis, caused by Salmonella species, is one of the most common foodborne illnesses worldwide with an estimated 93.8 million cases and about 155,00 fatalities. In both industrialized and developing nations, Salmonellosis has been reported to be one of the most prevalent foodborne zoonoses and is linked with arrays of illness syndromes such as acute and chronic enteritis, and septicaemia. The two major and most common Salmonella species implicated in both warm-blooded and cold-blooded animals are Salmonella bongori and Salmonella enterica. To date, more than 2400 S. enterica serovars which affect both humans and animals have been identified. Salmonella is further classified into serotypes based on three primary antigenic determinants: somatic (O), flagella (H), and capsular (K). The capacity of nearly all Salmonella species to infect, multiply, and survive in human host cells with the aid of their pathogenic and virulence arsenals makes them deadly and important public health pathogens. Primarily, food-producing animals such as poultry, swine, cattle, and their products have been identified as important sources of salmonellosis. Additionally, raw fruits and vegetables are among other food types that have been linked to the spread of Salmonella spp. Based on the clinical manifestation of human salmonellosis, Salmonella strains can be categorized as either non-typhoidal Salmonella (NTS) and typhoidal Salmonella. The detection of aseptically collected Salmonella in necropsies, environmental samples, feedstuffs, rectal swabs, and food products serves as the basis for diagnosis. In developing nations, typhoid fever due to Salmonella Typhi typically results in the death of 5%-30% of those affected. The World Health Organization (WHO) calculated that there are between 16 and 17 million typhoid cases worldwide each year, with scaring 600,000 deaths as a result. The contagiousness of a Salmonella outbreak depends on the bacterial strain, serovar, growth environment, and host susceptibility. Risk factors for Salmonella infection include a variety of foods; for example, contaminated chicken, beef, and pork. Globally, there is a growing incidence and emergence of life-threatening clinical cases, especially due to multidrug-resistant (MDR) Salmonella spp, including strains exhibiting resistance to important antimicrobials such as beta-lactams, fluoroquinolones, and third-generation cephalosporins. In extreme cases, especially in situations involving very difficult-to-treat strains, death usually results. The severity of the infections resulting from Salmonella pathogens is dependent on the serovar type, host susceptibility, the type of bacterial strains, and growth environment. This review therefore aims to detail the nomenclature, etiology, history, pathogenesis, reservoir, clinical manifestations, diagnosis, epidemiology, transmission, risk factors, antimicrobial resistance, public health importance, economic impact, treatment, and control of salmonellosis.


Assuntos
Infecções por Salmonella , Animais , Humanos , Fatores de Risco , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/microbiologia , Salmonelose Animal/microbiologia , Salmonelose Animal/epidemiologia , Salmonella/classificação , Salmonella/fisiologia , Salmonella/isolamento & purificação , Zoonoses
2.
Mol Biol Evol ; 39(9)2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36124912

RESUMO

Quantifying the magnitude of the global extinction crisis is important but remains challenging, as many extinction events pass unnoticed owing to our limited taxonomic knowledge of the world's organisms. The increasing rarity of many taxa renders comprehensive sampling difficult, further compounding the problem. Vertebrate lineages such as birds, which are thought to be taxonomically well understood, are therefore used as indicator groups for mapping and quantifying global extinction. To test whether extinction patterns are adequately gauged in well-studied groups, we implemented ancient-DNA protocols and retrieved whole genomes from the historic DNA of museum specimens in a widely known songbird radiation of shamas (genus Copsychus) that is assumed to be of least conservation concern. We uncovered cryptic diversity and an unexpected degree of hidden extinction and terminal endangerment. Our analyses reveal that >40% of the phylogenetic diversity of this radiation is already either extinct in the wild or nearly so, including the two genomically most distinct members of this group (omissus and nigricauda), which have so far flown under the conservation radar as they have previously been considered subspecies. Comparing the genomes of modern samples with those from roughly a century ago, we also found a significant decrease in genetic diversity and a concomitant increase in homozygosity affecting various taxa, including small-island endemics that are extinct in the wild as well as subspecies that remain widespread across the continental scale. Our application of modern genomic approaches demonstrates elevated levels of allelic and taxonomic diversity loss in a songbird clade that has not been listed as globally threatened, highlighting the importance of ongoing reassessments of extinction incidence even across well-studied animal groups. Key words: extinction, introgression, white-rumped shama, conservation.


Assuntos
Aves Canoras , Animais , DNA/genética , Extinção Biológica , Genoma , Filogenia , Aves Canoras/genética
3.
Elife ; 92020 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-33350381

RESUMO

Archipelagoes serve as important 'natural laboratories' which facilitate the study of island radiations and contribute to the understanding of evolutionary processes. The white-eye genus Zosterops is a classical example of a 'great speciator', comprising c. 100 species from across the Old World, most of them insular. We achieved an extensive geographic DNA sampling of Zosterops by using historical specimens and recently collected samples. Using over 700 genome-wide loci in conjunction with coalescent species tree methods and gene flow detection approaches, we untangled the reticulated evolutionary history of Zosterops, which comprises three main clades centered in Indo-Africa, Asia, and Australasia, respectively. Genetic introgression between species permeates the Zosterops phylogeny, regardless of how distantly related species are. Crucially, we identified the Indonesian archipelago, and specifically Borneo, as the major center of diversity and the only area where all three main clades overlap, attesting to the evolutionary importance of this region.


Assuntos
Especiação Genética , Filogenia , Aves Canoras/genética , Animais , Fluxo Gênico/genética , Indonésia
4.
Vet World ; 12(10): 1540-1545, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31849414

RESUMO

AIM: This research aimed to identify Staphylococcus species isolated from preputial swabs of healthy Aceh cattle, based on 16S ribosomal RNA gene analysis. MATERIALS AND METHODS: The bacterium was isolated from preputial swabs of healthy Aceh cattle. The total DNA from the isolated bacteria was extracted using the Genomic DNA Mini Kit followed by polymerase chain reaction (PCR) amplification of the 16S rRNA gene. The product of PCR amplification was then sequenced and aligned to the known sequences in the GenBank database by multiple alignments and was also analyzed by bioinformatics software to construct a phylogenetic tree. RESULTS: The results revealed that the bacterial isolate 3A had genetically closed relation to Staphylococcus pasteuri with <97% maximum identity. Data derived from the phylogenetic tree revealed that the bacterial isolate 3A was also related to Staphylococcus warneri, yet, it shows a different evolutionary distance with the ancestors (S. pasteuri). CONCLUSION: The results of this research suggested that the bacterium 3A, isolated from preputial swabs of healthy Aceh cattle, is a Staphylococcus species.

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