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排序方式: 共有8098条查询结果,搜索用时 15 毫秒
1.
Zhao  Xiu-Juan  Zhang  Yi-Ran  Bai  Wen-Fei  Sun  Tong-Yan  Yang  Yu-Fen  Wang  Tong-Xin  Bai  Cui-Gai 《Inflammopharmacology》2022,30(5):1717-1728
Inflammopharmacology - The efficacy of the sulforaphane derivative JY4 was evaluated in acute and chronic mouse models of ulcerative colitis induced by dextran sodium sulfate. Oral administration...  相似文献   
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《Vaccine》2022,40(32):4440-4452
Coronavirus disease 2019 (COVID-19) is an acute respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The prevention of SARS-CoV-2 transmission has become a global priority. Previously, we showed that a protein subunit vaccine that was developed based on the fusion of the SARS-CoV-2 receptor-binding domain (RBD) to the Fc portion of human IgG1 (RBD-Fc), produced in Nicotiana benthamiana, and adjuvanted with alum, namely, Baiya SARS-CoV-2 Vax 1, induced potent immunological responses in both mice and cynomolgus monkeys. Hence, this study evaluated the protective efficacy, safety, and toxicity of Baiya SARS-CoV-2 Vax 1 in K18-hACE2 mice, monkeys and Wistar rats. Two doses of vaccine were administered three weeks apart on Days 0 and 21. The administration of the vaccine to K18-hACE2 mice reduced viral loads in the lungs and brains of the vaccinated animals and protected the mice against challenge with SARS-CoV-2. In monkeys, the results of safety pharmacology tests, general clinical observations, and a core battery of studies of three vital systems, namely, the central nervous, cardiovascular, and respiratory systems, did not reveal any safety concerns. The toxicology study of the vaccine in rats showed no vaccine-related pathological changes, and all the animals remained healthy under the conditions of this study. Furthermore, the vaccine did not cause any abnormal toxicity in rats and was clinically tolerated even at the highest tested concentration. In addition, general health status, body temperature, local toxicity at the administration site, hematology, and blood chemistry parameters were also monitored. Overall, this work presents the results of the first systematic study of the safety profile of a plant-derived vaccine, Baiya SARS-CoV-2 Vax 1; this approach can be considered a viable strategy for the development of vaccines against COVID-19.  相似文献   
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《Vaccine》2022,40(16):2370-2378
Porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (M. hyopneumoniae, Mhp) are two of the most common pathogens involved in the porcine respiratory disease complex (PRDC) resulting in significant economic losses worldwide. Vaccination is the most effective approach to disease prevention. Since PRRSV and Mhp co-infections are very common, an efficient dual vaccine against these pathogens is required for the global swine industry. Compared with traditional vaccines, multi-epitope vaccines have several advantages, they are comparatively easy to produce and construct, are chemically stable, and do not have an infectious potential. In this study, to develop a safe and effective vaccine, B cell and T cell epitopes of PRRSV-GP5, PRRSV-M, Mhp-P46, and Mhp-P65 protein had been screened to construct a recombinant epitope protein rEP-PM that has good hydrophilicity, strong antigenicity, and high surface accessibility, and each epitope is independent and complete. After immunization in mice, rEP-PM could induce the production of high levels of antibodies, and it had good immunoreactivity with anti-rEP-PM, anti-PRRSV, and anti-Mhp antibodies. The anti-rEP-PM antibody specifically recognizes proteins from PRRSV and Mhp. Moreover, rEP-PM induced a Th1-dominant cellular immune response in mice. Our results showed that the rEP-PM protein could be a potential candidate for the development of a safe and effective multi-epitope peptide combined vaccine to control PRRSV and Mhp infections.  相似文献   
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《Ticks and Tick》2022,13(3):101934
Anaplasmosis is a tick-transmitted disease due to several species of the genus Anaplasma. In 2019, we demonstrated the presence of Anaplasma capra in two deer species at a zoological park in mainland France. As we suspected its presence in Corsica, we surveyed 11 geographically distant sheep or goat farms. Using molecular tools such as nested PCR targeting 16S ribosomal RNA (rRNA), citrate synthase (gltA) and heat-shock protein (groEL) genes, we detected the presence of A. capra on 5/11 farms, in 26/108 blood samples (24%), in sheep as well as in goats. Genotyping and phylogenetic analysis of A. capra revealed that isolates from Corsica island grouped closely with A. capra isolates reported in red deer and swamp deer from a zoological reserve in mainland France, as well as in roe deer from Spain, in a separate and well supported clade within A. capra clade II. This third report of the tick-borne bacterium A. capra in Europe suggests a potentially larger presence of this pathogen on the European continent, on domestic, native as well as wild ruminants, a broad host range already described in Asian countries for this species.  相似文献   
7.
《Ticks and Tick》2022,13(5):101974
Rodents are generally recognized to be the reservoir hosts of a great many zoonotic pathogens. In some areas of China, rodent-borne pathogens, as well as the role of rodents in the natural cycle of these pathogens, are still poorly investigated. To increase our knowledge on the distribution and epidemiology of rodent-borne bacterial pathogens, 81 rodent liver samples were collected in three locations of Guizhou province located in Southwest China, and screened for the presence of Ehrlichia, Coxiella, and Bartonella in them. A putative novel Ehrlichia species was identified in 5 Berylmys bowersi samples (100%, 5/5). Its 16S rRNA, gltA, and groEL genes have highest 99.84%, 89.11%, and 98.02% identities to those from known Ehrlichia species, and form distinct clades in the phylogenetic trees. Herein we name it “Candidatus Ehrlichia zunyiensis”. Bartonella was tested positive in 8 A. agrarius (striped field mouse), 2 A. chevrieri (Chevrier's field mouse), 1 R. norvegicus (Norway rat), 1 N. confucianus, and 1 N. lotipes, with a total positive rate of 16.05% (13/81). Sequence analysis indicated high genetic diversity in these Bartonella strains. Unexpectedly, two Coxiella strains were identified from the rodents (1 Niviventer confucianus and 1 Mus pahari). Genetic and phylogenetic analysis indicated that both of them are closely related to the Coxiella endosymbiont of ticks. This result supported previous conjectures that vertebrate hosts such as rodents may play a role in the preservation and transmission of Coxiella endosymbiont of ticks.  相似文献   
8.
BackgroundCryptococcus neoformans infections occur in immunocompromised patients, especially those with HIV infection, chemoradiotherapy after cancer, and organ transplantation. Infection can cause pneumonia and meningoencephalitis in severe cases with a high mortality rate if not treated. Although fluconazole and amphotericin B are the first-line treatments for cryptococcosis, the rate of fluconazole resistance has increased significantly due to long-term use. Minocycline is a derivative of tetracycline that exerts its antibacterial effect through inhibition of bacterial protein synthesis. It is also able to pass the blood-brain barrier to act on the central nervous system. The present study investigates the effects of minocycline in combination with antifungals in treating C. neoformans.ObjectiveTo determine in vitro interactions of minocycline combined with itraconazole, voriconazole, posaconazole, fluconazole and amphotericin B against C. neoformans.MethodsThe minimum inhibitory concentrations (MIC) of the antifungals were determined by the CLSI Clinical and Laboratory Standards Institute M27-A3 microdilution method. The in vitro synergistic effects of minocycline combined with itraconazole, voriconazole, posaconazole, fluconazole, and amphotericin B on C. neoformans were detected by the broth microdilution checkerboard technique and disk diffusion testing.Results and ConclusionThe working concentration ranges were 0.125–4 µg/mL for itraconazole, 0.03–0.125 µg/ml for voriconazole, 0.03–1 µg/ml for posaconazole, 0.25–16 µg/ml for fluconazole, and 0.125–2 µg/ml for amphotericin B. The synergistic rates of minocycline combinations against C. neoformans were 55% with itraconazole, 10% with voriconazole, 85% with posaconazole, 20% with fluconazole, and 70% with amphotericin B. The effective MIC value of minocycline in the synergistic combination decreased to 2–32 µg/ml, while the MIC of itraconazole decreased to 0.03–0.125 µg/ml, voriconazole 0.03–0.125 µg/ml, posaconazole 0.03–0.125 µg/ml, 0.125–4 µg/ml fluconazole, and 0.06–0.50 µg/ml amphotericin B. The disk diffusion assay showed that the plates containing minocycline and antifungal drugs produced inhibition zones with diameters larger than the single drug plates. Minocycline showed no antagonistic effect in the combinations. In conclusion, the combination of minocycline and azoles or amphotericin B has synergistic effects against C. neoformans in vitro.  相似文献   
9.
Wang  Liang  Yang  Huibin  Qiao  Liang  Liu  Jiani  Liao  Xiaoxiao  Huang  Huan  Dong  Jianyi  Chen  Jun  Chen  Dapeng  Wang  Jingyu 《Inflammation》2022,45(4):1720-1731
Inflammation - The sustained activation of the nuclear factor κB (NF-κB) signaling pathway has been observed in human inflammatory bowel disease (IBD). Ophiopogonin D (OP-D) is a small...  相似文献   
10.
《Ticks and Tick》2022,13(3):101912
Accelerated frequency of recreational travel, globalization of business, and legal and illegal plant and animal trades have contributed to enduring introductions of exotic ticks into the United States. We herein report a new incursion of a female Rhipicephalus capensis on a human traveler returning to Connecticut from South Africa. Natural distribution of R. capensis is restricted to the Western Cape Province and southwestern portion of the Northern Cape Province of South Africa, an area called the Fynbos Biome, and adults of this species primarily parasitize large, wild ungulate hosts. Only one previous international introduction of this tick is documented on imported South African plant material into the United States in 1985. The specimen described here was identified initially by morphological means and subsequently, a partial DNA sequence for the mitochondrial ribosomal RNA gene was generated in a PCR assay, which showed 94.86% identity to an R. capensis sequence in GenBank. We also provide information on several other previously unreported or under-reported incursions by South African ticks into the United States in association with imported Fynbos floricultural materials and speckled Cape tortoises, Chersobius signatus. Documentation of these additional exotic tick species incursions highlights ongoing challenges of the international movement of humans, animals, and other goods carrying ticks of human and veterinary importance.  相似文献   
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