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131.
Francisco F. Laranjeira Suely X. B. Silva Rachel E. Murray-Watson Ana C. F. Soares Hermes P. Santos-Filho Nik J. Cunniffe 《Plant pathology》2020,69(3):467-483
Citrus greasy spot (CGS), caused by Zasmidium citri, induces premature defoliation and yield loss in Citrus spp. The epidemiology of CGS is well understood in high humidity areas, but remains unaddressed in Brazil, despite differing climatic conditions and disease management practices. The spatiotemporal dynamics of CGS were characterized in the Recôncavo of Bahia (Brazil) at four hierarchical levels (quadrant, plant, grove, and region). A survey conducted in 19 municipalities found the disease to be present throughout the region with an incidence of 100% in groves and plants, and higher than 70% on leaves. Index of dispersion (D) values suggest the spatial pattern of units with symptoms lies between random and regular. This was confirmed by the parameters of the binary power law for plants and their quadrants (log[A] < 0 and b < 1). No consistent differences were observed in the disease incidence at different plant heights. We introduce a compartmental model synthesizing CGS epidemiology. The collected data allow such a model to be parameterized, albeit with some ambiguity over the proportion of new infections that result from inoculum produced within the grove versus external sources of infection. By extending the model to include two populations of growers—those who control and those who do not—coupled by airborne inoculum, we investigate likely performance of cultural controls accessible to citrus growers in northeastern Brazil. The results show that control via removal of fallen leaves can be very effective. However, successful control is likely to require area-wide strategies in which a large proportion of growers actively manage disease. 相似文献
132.
Neuroprotection in glaucoma using epoetin beta (EPOβ) has yielded promising results. Our team has developed chitosan-hyaluronic acid nanoparticles (CS/HA) designed to carry EPOβ into the ocular globe, improving the drug’s mucoadhesion and retention time on the ocular surface to increase its bioavailability. In the present in vivo study, we explored the possibility of delivering EPOβ to the eye through subconjunctival administration of chitosan-hyaluronic acid-EPOβ (CS/HA-EPOβ) nanoparticles. Healthy Wistar Hannover rats (n = 21) were split into 7 groups and underwent complete ophthalmological examinations, including electroretinography and microhematocrit evaluations before and after the subconjunctival administrations. CS/HA-EPOβ nanoparticles were administered to the right eye (OD), and the contralateral eye (OS) served as control. At selected timepoints, animals from each group (n = 3) were euthanized, and both eyes were enucleated for histological evaluation (immunofluorescence and HE). No adverse ocular signs, no changes in the microhematocrits (≈45%), and no deviations in the electroretinographies in both photopic and scotopic exams were observed after the administrations (p < 0.05). Intraocular pressure remained in the physiological range during the assays (11–22 mmHg). EPOβ was detected in the retina by immunofluorescence 12 h after the subconjunctival administration and remained detectable until day 21. We concluded that CS/HA nanoparticles could efficiently deliver EPOβ into the retina, and this alternative was considered biologically safe. This nanoformulation could be a promising tool for treating retinopathies, namely optic nerve degeneration associated with glaucoma. 相似文献
133.
José Francisco Nieto-Cabrales Beatriz Salceda-Sánchez Héctor M. Zazueta-Islas Marlene Solís-Cortés Magaly Guadalupe Landa-Flores Juan Carlos del Mazo-López Laura Valtierra-Alzaga Juan J. Soto-Gutiérrez Heron Huerta-Jimenez Ingeborg Becker Jorge J. Rodríguez-Rojas Sokani Sánchez-Montes 《Zoonoses and public health》2024,71(2):217-224
134.
The furcation region morphology was evaluated in 103 mature feline carnassial teeth (54 maxillary fourth premolar and 49 mandibular first molar teeth). Patent furcation canals were present in 27.2% of teeth. No significant difference (p = 0.88) in distribution of this anatomical variation was found between maxillary fourth premolar and mandibular first molar teeth. The mean width of these furcation canals was 104.0 microns with two-thirds of the canals having a buccal orientation. The presence of furcation canals could be a factor in the etiopathogenesis of feline dental resorptive lesions, as well as a characteristic to be considered in the diagnosis, prognosis, and treatment of endodontic or periodontic-endodontic lesions in cat teeth. 相似文献
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137.
The enrichment of live fences with native tree species has been proposed as a conservation strategy in agricultural landscapes; however, little research has explored ways to do this in tropical areas. This study examines selection of native tree species, effects of damage caused by mammals (mainly cattle) in performance (survival and growth) of transplanted seedlings, and cost-benefit balances as critical steps to enrich tropical live fences. Seven native tree species, with ecological and socio-economic importance, were selected in a Mexican agricultural landscape to grow as seedlings, and six of them were transplanted into live fences of cattle ranches with different levels of cattle activity (none/moderate/high). Costs associated with propagation and seedling protection in the field were calculated, and performance and damage in seedlings were measured over 2 years. We developed an index to identify species with the best performance and lowest costs in sites with cattle activity. Our results showed that damage, caused mainly by cattle, reduced the performance of transplanted seedlings. The effect of this damage varied depending on its severity (level and frequency) and the identity and life history of species. All selected species performed well in the site without cattle access. Dendropanax arboreus was the best species at site with moderate cattle activity, and Trema micrantha and Saurauia scabrida at site with high cattle activity. These species are recommended for enriching live fences because of good cost-benefit balance. This approach could be an important quantitative method to select species useful not only in agroforestry but also in restoration projects, which normally remain under the pressure of domestic and wild animals. 相似文献
138.
Eudes Esteves do Nascimento Ana Sue SammiJoeleni Rosa Dos Santos Beatriz de Souza Lima NinoAlexey Leon Gomel Bogado Alessandra TarodaOdilon Vidotto João Luis Garcia 《Comparative immunology, microbiology and infectious diseases》2014
The aim of the present study was to evaluate anti-Neospora caninum antibodies and the vertical transmission rate in naturally infected pregnant zebu beef cows (Bos indicus) reared on pasture. The present study began with 200 cows from four farms (50 cows from each farm), and these animals were submitted to timed artificial insemination (TAI). After ultrasonography, 76 pregnant cows were selected, 22, 15, 22, and 17, respectively, from farms 1, 2, 3, and 4. Blood samples were taken from cows thrice during the first, second, and third trimester of gestation, and a blood sample was collected from 31 calves before colostrum milking. From 76 cows 23 (30.3%) had anti-N. caninum antibodies detected by indirect ELISA (Idexx), and 53 (69.7%) did not. Sixty-four cows that initiated the experiment were negative to N. caninum and 11 became positive either during the second or third trimester of gestation, this mean an infection incidence of 17.2% (11/64). OD for ELISA was higher (OD = 2.08) during the second and third (OD = 2.10) trimesters of pregnancy when compared with the first (OD = 1.81), however, there were no statistical differences (P = 0.45). The vertical transmission was calculated to be 29.0% (9/31), and the risk of vertical transmission of N. caninum in seropositive dams was 26.25 times higher than seronegative animals (OR = 26.25, 2.38 < OR < 289, P = 0.007). In conclusion, the rate of vertical transmission of N. caninum in pregnant zebu beef cows was 29%, and the risk was 26.25 higher in seropositive dams relative to than seronegative animals. 相似文献
139.
Beatriz Vida?a Jorge Martínez Pamela Martínez-Orellana Lourdes García Migura María Montoya Jaime Martorell Natàlia Majó 《Veterinary research》2014,45(1)
The swine-origin pandemic (p) H1N1 influenza A virus causes mild upper-respiratory tract disease in most human patients. However, some patients developed severe lower-respiratory tract infections with fatal consequences, and the cause of these infections remain unknown. Recently, it has been suggested that different populations have different degrees of susceptibility to pH1N1 strains due to host genetic variations that are associated with inappropriate immune responses against viral genetic characteristics. Here, we tested whether the pathologic patterns of influenza strains that produce different disease outcomes in humans could be reproduced in a ferret model. Our results revealed that the severities of infection did not correspond to particular viral isolate and were not associated with the clinical phenotypes of the corresponding patients. Severe pathological outcomes were associated with higher viral replication, especially in alveolar areas, and with an exacerbated innate cellular immune response that was characterised by substantial phagocytic and cytotoxic cell migration into the lungs. Moreover, detrimental innate cellular responses were linked to the up-regulation of several proinflammatory cytokines and chemokines and the down-regulation of IFNα in the lungs. Additionally, severe lung lesions were associated with greater up-regulations of pro-apoptotic markers and higher levels of apoptotic neutrophils and macrophages. In conclusion, this study confirmed that the clinicopathological outcomes of pH1N1 infection in ferrets were not only due to viral replication abilities but also depended on the hosts’ capacities to mount efficient immune responses to control viral infection of the lung.
Electronic supplementary material
The online version of this article (doi:10.1186/s13567-014-0085-8) contains supplementary material, which is available to authorized users. 相似文献140.
Daniela Vallejo Irene Crespo Beatriz San-Miguel Marcelino álvarez Jesús Prieto María Jesús Tu?ón Javier González-Gallego 《Veterinary research》2014,45(1):15
The Rabbit Hemorrhagic Disease Virus (RHDV) induces a severe disease that fulfils many requirements of an animal model of fulminant hepatic failure. However, a better knowledge of molecular mechanisms contributing to liver damage is required, and it is unknown whether the RHDV induces liver autophagy and how it relates to apoptosis. In this study, we attempted to explore which signalling pathways were involved in the autophagic response induced by the RHDV and to characterize their role in the context of RHDV pathogenesis. Rabbits were infected with 2 × 104 hemmaglutination units of a RHDV isolate. The autophagic response was measured as presence of autophagic vesicles, LC3 staining, conversion of LC3-I to autophagosome-associated LC3-II and changes in expression of beclin-1, UVRAG, Atg5, Atg12, Atg16L1 and p62/SQSTM1. RHDV-triggered autophagy reached a maximum at 24 hours post-infection (hpi) and declined at 30 and 36 hpi. Phosphorylation of mTOR also augmented in early periods of infection and there was an increase in the expression of the endoplasmic reticulum chaperones BiP/GRP78, CHOP and GRP94. Apoptosis, measured as caspase-3 activity and expression of PARP-1, increased significantly at 30 and 36 hpi in parallel to the maximal expression of the RHDV capsid protein VP60. These data indicate that RHDV infection initiates a rapid autophagic response, perhaps in an attempt to protect liver, which associates to ER stress development and is independent from downregulation of the major autophagy suppressor mTOR. As the infection continues and the autophagic response declines, cells begin to exhibit apoptosis. 相似文献