Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Sci Rep ; 14(1): 3756, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355905

RESUMO

The anthropogenic impact on wildlife is ever increasing. With shrinking habitats, wild populations are being pushed to co-exist in proximity to humans leading to an increased threat of infectious diseases. Therefore, understanding the immune system of a species is key to assess its resilience in a changing environment. The innate immune system (IIS) is the body's first line of defense against pathogens. High variability in IIS genes, like toll-like receptor (TLR) genes, appears to be associated with resistance to infectious diseases. However, few studies have investigated diversity in TLR genes in vulnerable species for conservation. Large predators are threatened globally including leopards and cheetahs, both listed as 'vulnerable' by IUCN. To examine IIS diversity in these sympatric species, we used next-generation-sequencing to compare selected TLR genes in African leopards and cheetahs. Despite differences, both species show some TLR haplotype similarity. Historic cheetahs from all subspecies exhibit greater genetic diversity than modern Southern African cheetahs. The diversity in investigated TLR genes is lower in modern Southern African cheetahs than in African leopards. Compared to historic cheetah data and other subspecies, a more recent population decline might explain the observed genetic impoverishment of TLR genes in modern Southern African cheetahs. However, this may not yet impact the health of this cheetah subspecies.


Assuntos
Acinonyx , Doenças Transmissíveis , Panthera , Humanos , Animais , Acinonyx/genética , Panthera/genética , Animais Selvagens/genética , Ecossistema
2.
J Hered ; 114(3): 271-278, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-36869783

RESUMO

The cheetah (Acinonyx jubatus, SCHREBER 1775) is a large felid and is considered the fastest land animal. Historically, it inhabited open grassland across Africa, the Arabian Peninsula, and southwestern Asia; however, only small and fragmented populations remain today. Here, we present a de novo genome assembly of the cheetah based on PacBio continuous long reads and Hi-C proximity ligation data. The final assembly (VMU_Ajub_asm_v1.0) has a total length of 2.38 Gb, of which 99.7% are anchored into the expected 19 chromosome-scale scaffolds. The contig and scaffold N50 values of 96.8 Mb and 144.4 Mb, respectively, a BUSCO completeness of 95.4% and a k-mer completeness of 98.4%, emphasize the high quality of the assembly. Furthermore, annotation of the assembly identified 23,622 genes and a repeat content of 40.4%. This new highly contiguous and chromosome-scale assembly will greatly benefit conservation and evolutionary genomic analyses and will be a valuable resource, e.g., to gain a detailed understanding of the function and diversity of immune response genes in felids.


Assuntos
Acinonyx , Animais , Acinonyx/genética , Cromossomos/genética , Genoma , Genômica , Filogenia , Anotação de Sequência Molecular
3.
Conserv Genet ; 24(1): 125-136, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36694805

RESUMO

There are only about 7,100 adolescent and adult cheetahs (Acinonyx jubatus) remaining in the wild. With the majority occurring outside protected areas, their numbers are rapidly declining. Evidence-based conservation measures are essential for the survival of this species. Genetic data is routinely used to inform conservation strategies, e.g., by establishing conservation units (CU). A commonly used marker in conservation genetics is mitochondrial DNA (mtDNA). Here, we investigated the cheetah's phylogeography using a large-scale mtDNA data set to refine subspecies distributions and better assign individuals to CUs. Our dataset mostly consisted of historic samples to cover the cheetah's whole range as the species has been extinct in most of its former distribution. While our genetic data largely agree with geography-based subspecies assignments, several geographic regions show conflicting mtDNA signals. Our analyses support previous findings that evolutionary forces such as incomplete lineage sorting or mitochondrial capture likely confound the mitochondrial phylogeography of this species, especially in East and, to some extent, in Northeast Africa. We caution that subspecies assignments solely based on mtDNA should be treated carefully and argue for an additional standardized nuclear single nucleotide polymorphism (SNP) marker set for subspecies identification and monitoring. However, the detection of the A. j. soemmeringii specific haplogroup by a newly designed Amplification-Refractory Mutation System (ARMS) can already provide support for conservation measures. Supplementary Information: The online version contains supplementary material available at 10.1007/s10592-022-01483-1.

4.
Mol Ecol ; 31(16): 4208-4223, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35748392

RESUMO

We live in a world characterized by biodiversity loss and global environmental change. The extinction of large carnivores can have ramifying effects on ecosystems like an uncontrolled increase in wild herbivores, which in turn can have knock-on impacts on vegetation regeneration and communities. Cheetahs (Acinonyx jubatus) serve important ecosystem functions as apex predators; yet, they are quickly heading towards an uncertain future. Threatened by habitat loss, human-wildlife conflict and illegal trafficking, there are only approximately 7100 individuals remaining in nature. We present the most comprehensive genome-wide analysis of cheetah phylogeography and conservation genomics to date, assembling samples from nearly the entire current and past species' range. We show that their phylogeography is more complex than previously thought, and that East African cheetahs (A. j. raineyi) are genetically distinct from Southern African individuals (A. j. jubatus), warranting their recognition as a distinct subspecies. We found strong genetic differentiation between all classically recognized subspecies, thus refuting earlier findings that cheetahs show only little differentiation. The strongest differentiation was observed between the Asiatic and all the African subspecies. We detected high inbreeding in the Critically Endangered Iranian (A. j. venaticus) and North-western (A. j. hecki) subspecies, and show that overall cheetahs, along with snow leopards, have the lowest genome-wide heterozygosity of all the big cats. This further emphasizes the cheetah's perilous conservation status. Our results provide novel and important information on cheetah phylogeography that can support evidence-based conservation policy decisions to help protect this species. This is especially relevant in light of ongoing and proposed translocations across subspecies boundaries, and the increasing threats of illegal trafficking.


Assuntos
Acinonyx , Acinonyx/genética , Animais , Ecossistema , Genoma , Genômica , Humanos , Irã (Geográfico)
5.
Clin Nephrol ; 84(5): 280-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26396097

RESUMO

BACKGROUND: Epoetin-zeta (epoetin-ζ) (sold as Retacrit™/Silapo™) is a biologic product that was approved by the European Medicines Agency in 2007 after demonstrating biosimilarity to its reference product epoetin-α (Eprex™), based on a comprehensive comparability exercise including extensive biophysical characterization and three double-blind randomized controlled trials. Since 2008, epoetin-ζ has been prescribed by physicians across Europe to treat anemia of renal disease in many thousands of patients. METHODS: Provided here are results of the PASCO I study (post-authorization safety cohort observation of silapo/retacrit (epoetin-ζ) administered intravenously for the treatment of renal anemia). The primary study endpoint was the frequency of adverse events of special interest (AESI) occurring in patients receiving epoetin-ζ over a 1-year study observation period. RESULTS: The safety set included 1,634 patients who received at least 1 dose of epoetin-ζ during the study period. These patients experienced AESI at these frequencies: clotting of artificial kidney 9.8%, lack of efficacy 2.3%, cerebrovascular events (including cerebrovascular accident, cerebral infarction, cerebral hemorrhage, and transient ischemic attack) 1.8%, myocardial infarction 1.7%, acute myocardial infarction 1.2%, clinically relevant hyperkalemia 0.4%, deep vein thrombosis 0.2%, convulsion 0.2%, hypertensive encephalopathy 0.1%, and pulmonary embolism 0.1%. No patients were reported as having anaphylactoid reactions, angioedema, erythropoietinneutralizing antibodies, or pure red cell aplasia. The median weekly follow-up dose of epoetin-ζ was 158.6 IU/kg. Mean hemoglobin concentration ranged between 11.3 and 11.7 g/dL. From the safety set, 228 patients died (14.0%), while 1,135 patients (74.9%; excluding 119 with data missing) continued treatment with epoetin-ζ following the 12-month observation. CONCLUSION: The PASCO I study contributes significantly to current knowledge about the frequency of adverse events associated with the use of epoetin-ζ for the treatment of renal anemia and demonstrates a pattern of adverse events comparable with data for other existing epoetin products in Europe.


Assuntos
Anemia/tratamento farmacológico , Medicamentos Biossimilares/efeitos adversos , Eritropoetina/efeitos adversos , Falência Renal Crônica/complicações , Idoso , Anemia/etiologia , Eritropoetina/uso terapêutico , Feminino , Hemoglobinas/análise , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Diálise Renal/efeitos adversos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA