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101.
Quichimbo Pablo Jiménez Leticia Veintimilla Darío Potthast Karin Tischer Alexander Günter Sven Mosandl Reinhard Hamer Ute 《New Forests》2020,51(2):313-334
New Forests - Information about nutrient dynamics is of upmost importance in order to contribute to the restoration of degraded forest environments in the Andes of southern Ecuador. This study aims... 相似文献
102.
Amanda S. Hirata James J. La Clair Paula C. Jimenez Leticia Veras Costa-Lotufo William Fenical 《Marine drugs》2022,20(5)
The bioactive natural product seriniquinone was discovered as a potential melanoma drug, which was produced by the as-yet-undescribed marine bacterium of the rare genus Serinicoccus. As part of a long-term research program aimed at the discovery of new agents for the treatment of cancer, seriniquinone revealed remarkable in vitro activity against a diversity of cancer cell lines in the US National Cancer Institute 60-cell line screening. Target deconvolution studies defined the seriniquinones as a new class of melanoma-selective agents that act in part by targeting dermcidin (DCD). The targeted DCD peptide has been recently examined and defined as a “pro-survival peptide” in cancer cells. While DCD was first isolated from human skin and thought to be only an antimicrobial peptide, currently DCD has been also identified as a peptide associated with the survival of cancer cells, through what is believed to be a disulfide-based conjugation with proteins that would normally induce apoptosis. However, the significantly enhanced potency of seriniquinone was of particular interest against the melanoma cell lines assessed in the NCI 60-cell line panel. This observed selectivity provided a driving force that resulted in a multidimensional program for the discovery of a usable drug with a new anticancer target and, therefore, a novel mode of action. Here, we provided an overview of the discovery and development efforts to date. 相似文献
103.
Leticia B. Oliveira Brittany J. McHale Guilherme G. Verocai Daniel R. Rissi 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(8):854
Canine subcutaneous dirofilariasis is rare and typically caused by Dirofilaria repens. An adult male, intact, mixed breed dog from South Carolina, USA, was examined because of physical trauma to the right maxilla. The dog died during hospitalization and was submitted for necropsy. Gross post-mortem changes included approximately 150 adult nematodes morphologically consistent with Dirofilaria spp. in the pulmonary artery, right atrium, and right ventricle. Histologically there was widespread proliferative pulmonary endarteritis with intraluminal nematodes morphologically consistent with Dirofilaria spp. Four similar nematodes were present in the subcutaneous tissue of the left medial thigh and tibial area. These nematodes were located within the fascia and skeletal muscles. They were surrounded by epithelioid macrophages and multinucleated giant cells, with some lymphocytes and plasma cells, and areas of mineralization (interpreted as mineralized cross sections of nematodes). Nematodes were morphologically identified as D. immitis. Subcutaneous dirofilariasis caused by D. immitis occurs when migrating nematode larvae develop into adults in the subcutaneous and skeletal muscle tissues.Key clinical message:Subcutaneous dirofilariasis in dogs is rare and most often associated with Dirofilaria repens. This case highlights the pathology findings of subcutaneous D. immitis in a dog. 相似文献
104.
Aldcejam Martins da Fonseca Junior Vincenzo Gaita Daniel Ricardo Argumedo Leticia Signori de Castro João Diego de Agostini Losano Roberta Ferreira Leite Marcilio Nichi Mayra Elena Ortiz d’Ávila Assumpção Daniele Ribeiro de Araújo Antonio Alvaro Ranha Neves Marcella Pecora Milazzotto 《Reproduction in domestic animals》2020,55(8):974-983
The female reproductive tract, in particular the composition of the uterine and oviduct fluids, is responsible, at least in part, for triggering sperm cell modifications, essential for the acquisition of fertilization ability. Hyaluronic acid (HA) is a glycosaminoglycan present in these fluids, and its role in the fertilization process and sperm functionality is still barely understood. This work was designed to (a) determine the rheological characteristics of the fertilization medium by the addition of HA and (b) determine the HA influence on sperm motility and functional status. To that end, the in vitro fertilization medium was supplemented with 4 doses of HA (6, 60, 600 and 6,000 µg/ml) and analysed for viscosity and adhesion strength characteristics. Then, thawed semen from 6 bulls were incubated in these media and assessed at 4 different moments for morphological and functional parameters (plasma and acrosomal membrane integrities, mitochondrial membrane potential, capacitation, acrosomal reaction, and motility). The rheological evaluation showed that the addition of HA was able to increase both the viscosity and the adhesion strength of the fertilization medium, especially in the 6,000 µg/ml group in which the effect was more pronounced. No influence of HA could be observed on mitochondrial potential, and acrosomal and plasma membrane integrities. However, HA supplementation, at lower doses, led to an increase in the number of reacted sperm, as well as changes in motility parameters, with increase in the number of motile, rapid and progressive spermatozoa. In conclusion, the addition of HA alters the rheological properties of the fertilization medium and leads to the improvement of the properties related to sperm motility and capacitation, without compromising other functional aspects of the cell. 相似文献
105.
Damiano Coppolecchia Sotirios Vasileiadis Nicoleta Suciu Rebecca Hamon Gian Maria Beone Marco Trevisan 《Soil biology & biochemistry》2011,43(9):1798-1807
This study investigated the responses to Zn of selected enzymatic activities, potential nitrification and microbial activity in a soil contaminated with Zn at concentrations ranging from 74 to 3490 mg kg−1. The main aims of the study were to evaluate different models for EC50 estimation and to compare the relative sensitivity to Zn of the different biological properties studied. The EC50 for each property was calculated using three different models, namely a logistic dose response model, and a full and a partial inhibition model based on Michaelis-Menten kinetics. Both total (aqua regia extractable) and labile (CaCl2 extractable) Zn content were assessed and employed for application of the models. A response to increasing Zn concentrations was observed for most of the biological properties except for fluorescein diacetate hydrolysis activity (FDA) and acid phosphatase activity. Among the three models tested, the logistic model had the widest applicability and generally gave the best results in terms of EC50 estimation and R2 fit. Among the two kinetics models tested, the partial inhibition model was applicable only in a few cases, but in these cases results are generally better than for the full inhibition model. The utilization of either total or labile Zn data did not significantly affect the outcomes of the models. The sensitivity of the biological properties to Zn was ranked according to the models as follows: nitrate reductase > potential nitrification > β-galactosidase > dehydrogenase > phenol oxidase = urease = arylsulphatase. These ranking results were generally in accordance with evidence provided by other researchers, thus showing that the relative sensitivity of these properties, especially the most sensitive ones, is generally constant among different soil types. The relevance of this finding for soil ecological risk assessment is discussed. 相似文献
106.
107.
Orsolya Kutasi Leticia Moravszki Sara Sardi Zsofia Bohak Imre Biksi Ferenc Baska Otto Szenci 《Journal of Equine Veterinary Science》2014
An 8-year-old Hungarian warmblood gelding used for show jumping was evaluated because of poor performance and chronic weight loss. On admission, oral and gastroesophageal ulcerations and malabsorption were detected. Results of thoracic radiography, ultrasonography, bronchoalveolar lavage cytology, and positive polymerase chain reaction for equine herpesvirus 5 raised the possible diagnosis of equine multinodular pulmonary fibrosis. However, abdominal ultrasonography revealed inhomogeneous spleen with many different sized well-demarcated hypoechoic areas, which suggested further differential diagnoses such as tuberculosis, neoplasias, immune mediated diseases, systemic granulomatous disease (SGD), or toxicoses. The horse was euthanized at the owner's request because of the poor condition and possible grave prognosis. Histopathology findings were characteristic of SGD, which is a rare disorder of horses characterized by skin lesions, weight loss, and granulomatous inflammation of multiple organ systems. The lack of skin lesions in this case is an unusual finding. Systemic granulomatous disease is hypothesized to be induced by multiple conventional antigens that are not cleared from affected tissues. Equine herpesvirus 5 might have triggered the granulomatous reactions in this particular case. 相似文献
108.
Molina-Botero Isabel Cristina Mazabel Johanna Arceo-Castillo Jeyder Urrea-Benítez José Luis Olivera-Castillo Leticia Barahona-Rosales Rolando Chirinda Ngonidzashe Ku-Vera Juan Arango Jacobo 《Tropical animal health and production》2020,52(6):2787-2798
Tropical Animal Health and Production - The purpose of this study was to determine the in vitro fermentation and methane (CH4) production in the grass Brachiaria brizantha (B) alone or when mixed... 相似文献
109.
Seasonal and environmentally induced variation in the type and frequency of leaf trichomes of Wigandia urens (Ruiz & Pavón) Kunth (Hydrophyllaceae) was studied. Depending on the microsite, W. urens plants had smooth leaves with glandular trichomes or bristly leaves with both glandular trichomes and urticant trichomes (stinging hairs). Trichome density (number of urticant trichomes per unit leaf area) was higher in the dry season than in the wet season, and was significantly correlated with both temperature (r = 0.353, P < 0.05) and photosynthetic active radiation (r = 0.313, P < 0.05). Plants established in sun-exposed areas had trichome densities three times higher than those of plants established in shaded areas during the dry season, and 28 times higher during the wet season. At both exposed and shaded sites, trichome densities of the youngest leaves of young plants were higher than those of the youngest leaves of mature plants. In smooth and bristly leaves, transpiration rates decreased with increasing temperature during the day. However, smooth leaves had higher transpiration rates than bristly leaves at both exposed and shaded sites. In laboratory studies, trichome density was significantly (P < 0.01) reduced when small sun-grown plants (0.20-0.30 m tall) were either shaded or irrigated. In larger plants, also, irrigation significantly (P < 0.01) reduced trichome density relative to that of unirrigated controls. 相似文献
110.
Leticia M. Mesa Cecilia Maldini Gisela Mayora Miguel Saigo Mercedes Marchese Federico Giri 《Journal of Soils and Sediments》2016,16(9):2316-2325