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91.
Nur Hazirah Hisamuddin Najat Hashim Sharmeen Nellisa Soffian Mohd Hishammfariz Mohd Amin Ridhwan Abdul Wahab Mardhiah Mohammad Muhammad Lokman Md Isa Afzan Mat Yusof 《The Korean journal of parasitology》2016,54(2):197-200
Cryptosporidium, a protozoan parasite, can cause cryptosporidiosis which is a gastrointestinal disease that can infect humans and livestock. Cattle are the most common livestock that can be infected with this protozoan. This study was carried out to determine the prevalence of Cryptosporidium infection in cattle in Kuantan, Pahang, Malaysia and to find out the association between the occurrence of infection and 3 different ages of cattle (calves less than 1 year, yearling, and adult cattle). The samples were processed by using formol-ether concentration technique and stained by modified Ziehl Neelsen. The results showed that 15.9% (24/151) of cattle were positive for Cryptosporidium oocysts. The occurrence of Cryptosporidium in calves less than 1 year was the highest with the percentage of 20.0% (11/55) followed by yearling and adult cattle, with the percentage occurrence of 15.6 % (7/45) and 11.8% (6/51), respectively. There was no significant association between the occurrence and age of cattle and presence of diarrhea. Good management practices and proper hygiene management must be taken in order to reduce the infection. It is highly important to control the infection since infected cattle may serve as potential reservoirs of the infection to other animals and humans, especially animal handlers. 相似文献
92.
?ukasz J. Sznajder Micha? Michalak Katarzyna Taylor Piotr Cywoniuk Micha? Kabza Agnieszka Wojtkowiak-Szlachcic Magdalena Mat?oka Patryk Konieczny Krzysztof Sobczak 《Nucleic acids research》2016,44(21):10326-10342
Muscleblind-like (MBNL) proteins are critical RNA processing factors in development. MBNL activity is disrupted in the neuromuscular disease myotonic dystrophy type 1 (DM1), due to the instability of a non-coding microsatellite in the DMPK gene and the expression of CUG expansion (CUGexp) RNAs. Pathogenic interactions between MBNL and CUGexp RNA lead to the formation of nuclear complexes termed foci and prevent MBNL function in pre-mRNA processing. The existence of multiple MBNL genes, as well as multiple protein isoforms, raises the question of whether different MBNL proteins possess unique or redundant functions. To address this question, we coexpressed three MBNL paralogs in cells at equivalent levels and characterized both specific and redundant roles of these proteins in alternative splicing and RNA foci dynamics. When coexpressed in the same cells, MBNL1, MBNL2 and MBNL3 bind the same RNA motifs with different affinities. While MBNL1 demonstrated the highest splicing activity, MBNL3 showed the lowest. When forming RNA foci, MBNL1 is the most mobile paralog, while MBNL3 is rather static and the most densely packed on CUGexp RNA. Therefore, our results demonstrate that MBNL paralogs and gene-specific isoforms possess inherent functional differences, an outcome that could be enlisted to improve therapeutic strategies for DM1. 相似文献
93.
94.
The spider tree of life: phylogeny of Araneae based on target‐gene analyses from an extensive taxon sampling 下载免费PDF全文
Ward C. Wheeler Jonathan A. Coddington Louise M. Crowley Dimitar Dimitrov Pablo A. Goloboff Charles E. Griswold Gustavo Hormiga Lorenzo Prendini Martín J. Ramírez Petra Sierwald Lina Almeida‐Silva Fernando Alvarez‐Padilla Miquel A. Arnedo Ligia R. Benavides Silva Suresh P. Benjamin Jason E. Bond Cristian J. Grismado Emile Hasan Marshal Hedin Matías A. Izquierdo Facundo M. Labarque Joel Ledford Lara Lopardo Wayne P. Maddison Jeremy A. Miller Luis N. Piacentini Norman I. Platnick Daniele Polotow Diana Silva‐Dávila Nikolaj Scharff Tamás Szűts Darrell Ubick Cor J. Vink Hannah M. Wood Junxia Zhang 《Cladistics : the international journal of the Willi Hennig Society》2017,33(6):574-616
95.
Can habitat characteristics shape vertebral morphology in dolphins? An example of two phylogenetically related species from southern South America 下载免费PDF全文
María Constanza Marchesi Matías Sebastián Mora Lida Elena Pimper Enrique Alberto Crespo Rae Natalie Prosser Goodall 《Marine Mammal Science》2017,33(4):1126-1148
Fast swimming pelagic cetacean species have osteological characteristics that promote a more stable spine in comparison to that of coastal species. The Peale's dolphin (Lagenorhynchus australis) and the hourglass dolphin (Lagenorhynchus cruciger) have a close phylogenetic relationship and are found in coastal and pelagic waters in the Southern Hemisphere, respectively. The aim of this work was to study the relationship between the vertebral column's morphology and its flexibility, across these species of contrasting habitats. Vertebral counts and multiple measurements of each vertebra were used to infer intervertebral flexibility. Bivariate plots and discriminant multivariate analyses were employed to compare each functional region along the vertebral column. Both species displayed a regionalization of the column into three stable regions and two flexible areas, which statistically differ in the proportion of the skeleton occupied in each species. While the Peale's dolphin has rounder vertebrae, associated with higher flexibility, the hourglass dolphin has disk‐shaped vertebrae and strongly inclined processes related to high stability. Although the species are closely related phylogenetically, vertebral morphology is influenced by a diverse set of ecological and behavioral factors, reflecting a high degree of vertebral plasticity within the genus. 相似文献
96.
Jesús Reolid Matías Reolid Christian Betzler Sebastian Lindhorst Martin G. Wiesner Niko Lahajnar 《Facies》2017,63(2):8
Cold-water corals of the Late Pleistocene (21,400–22,500 BP) are recorded from the sea-bottom of two inter-atoll channels (Kardiva Channel at 457-m depth and Malé Vaadhoo Channel at 443-m depth) of the eastern row of the Maldives archipelago. Coral assemblages are composed mainly by Lophelia pertusa and secondarily by Madrepora oculata and Enallopsammia rostrata. These cold-water coral patches are places where the benthic life, mainly sessile, is concentrated, which is clearly absent off-rubble patches. The main epibionts are tube-dwelling polychaetes (mainly Spirorbis and Serpula), bryozoans, siliceous sponges, barnacles, gorgonids, solitary corals, encrusting foraminifera, and microbial mats. The analysis of epibionts assemblages shows different biocoenoses between both studied sites as well as a dependency of the epibiont coverage with regard to the coral genus. Some living benthic organisms such as brachiopods, bivalves, gastropods, barnacles, and ophiuroids find refuge among coral branches. The common record of juvenile specimens of vagile organisms such as small ophiuroids, is probably related to the nursery function of the cold-water corals in spite they are fossils. Environmental requirements of Recent cold-water corals (Lophelia, Madrepora and Enallopsammia) differ of conditions at both sampling sites with sensibly lower oxygenation degree and density of waters than needed for cold-water corals. Therefore, it is proposed that the present-day oxygen and density conditions are the factors which inhibit modern cold-water coral growth in the inter-atoll channels. 相似文献
97.
S. Sakinah Sivan Padma Priya Sharmilah Kumari Fatin Amira Poorani K. Hiba Alsaeedy Mok Pooi Ling Hui-Yee Chee Akon Higuchi Abdullah A. Alarfaj Murugan A. Munusamy Kadarkarai Murugan Che Norma Mat Taib Palanisamy Arulselvan Mariappan Rajan Vasantha Kumari Neela Rukman Awang Hamat Giovanni Benelli S. Suresh Kumar 《Tissue & cell》2017,49(1):86-94
In this research, we characterized the histopathological impact of dengue virus (serotype DENV-2) infection in livers of BALB/c mice. The mice were infected with different doses of DENV-2 via intraperitoneal injection and liver tissues were processed for histological analyses and variation was documented. In the BALB/c mouse model, typical liver tissues showed regular hepatocyte architecture, with normal endothelial cells surrounding sinusoid capillary. Based on histopathological observations, the liver sections of BALB/c mice infected by DENV-2 exhibited a loss of cell integrity, with a widening of the sinusoidal spaces. There were marked increases in the infiltration of mononuclear cells. The areas of hemorrhage and micro- and macrovesicular steatosis were noted. Necrosis and apoptosis were abundantly present. The hallmark of viral infection, i.e., cytopathic effects, included intracellular edema and vacuole formation, cumulatively led to sinusoidal and lobular collapse in the liver. The histopathological studies on autopsy specimens of fatal human DENV cases are important to shed light on tissue damage for preventive and treatment modalities, in order to manage future DENV infections. In this framework, the method present here on BALB/c mouse model may be used to study not only the effects of infections by other DENV serotypes, but also to investigate the effects of novel drugs, such as recently developed nano-formulations, and the relative recovery ability with intact immune functions of host. 相似文献
98.
Justo Sánchez-Gil Emilio Guirao-Arrabal Ginés David Parra-García María del Pilar Luzón-García Maria Fe Bautista-Marín Matías Barayobre-Barayobre Andrés Fontalba-Navas 《Mycopathologia》2017,182(9-10):933-935
Mucormycosis is an unusual fungal infection that usually affects immunosuppressed patients. Small outbreaks of mucormycosis have been previously reported. We present two clinical cases of fatal rhinocerebral mucormycosis with a close temporal relationship between them and a possible nosocomial transmission: case 1 was a 75-year-old male with diabetes and COPD, treated with antibiotics and systemic corticosteroids, who developed rhinocerebral mucormycosis. Case 2 was an 88-year-old woman who was treated with systemic antibiotics and corticosteroids and developed the same infection after insertion of a nasogastric tube. Both patients concurred at the same time in our hospital, and healthcare staff was common to both of them. These cases, along with previously reported cases, highlight that, although infrequent, transmission of the fungus in the hospital environment is a real possibility that should be taken into account in order to initiate contact and air isolation precautions that could avoid nosocomial transmission of this infection. 相似文献
99.
Matías Reolid Christian Gaillard Federico Olóriz Francisco J. Rodríguez-Tovar 《Facies》2005,50(3-4):529-543
Two main types of microbial encrustation were identified in Middle Oxfordian to lowermost Kimmeridgian deposits in the Prebetic Zone (southern Spain), showing existing relationships between skeletal content, fabric and morphology of these organosedimentary structures. Laminated planar and concentric encrustations relate to peloidal fabrics (mainly constituted of microbes = microbial laminated fabrics s. str. and microbial oncoids s. str.), as well as to dense microbial fabrics periodically colonized by encrusting foraminifera (microbial laminated fabrics with nubeculariids and microbial oncoids with nubeculariids). Sedimentation rates, substrate stability and grain size, as well as illumination, influenced microbial growth pattern as major controlling factors in low-energy conditions, and forced palaeogeographic and stratigraphic patterns of distribution. Significant encrustation was identified in terrigenous-poor lithofacies from the middle (Transversarium-Bifurcatus zones) to the outer (Transversarium-Bimammatum zones) shelf in the Prebetic Zone. Rare-to-absent encrustation characterized terrigenous-rich deposits (Bimammatum and Planula zones) in the area. 相似文献
100.
Sue Mian Then Musalmah Mazlan Gapor Mat Top Wan Zurinah Wan Ngah 《Cellular and molecular neurobiology》2009,29(4):485-496
Besides acting as potent free radical scavengers, tocopherols and tocotrienols have been known to have non-antioxidant properties
such as the involvement of α-tocopherol (αT) in PKC pathway and the anti-cancer properties of γ-tocotrienol (γT3). This study
aims to elucidate whether protective effects shown by αT and γT3 in H2O2-induced neuron cultures have anti-apoptotic or pro-apoptotic tendency toward the initiation of neuronal apoptosis. H2O2 is used to induce apoptosis in primary cerebellar neuron cultures which is attenuated by pretreatment of αT or γT3 at concentrations
≤10 μM. Similar to our previous work, γT3 was found to be neurotoxic at concentrations ≥100 μM, whereas αT showed no neurotoxicity.
Cellular uptake of γT3 was higher than that of αT. Treating cells simultaneously with either γT3 or αT and with then H2O2 led to higher expression of Bax and Bcl-2 than in neurons exposed to H2O2 alone. Analysis of Bcl-2/Bax ratio as ‘survival index’ showed that both pretreatment of γT3 and αT followed by H2O2 increase the ‘survival index’ of Bcl-2/Bax ratio compared to H2O2-treated cells, while treatment of γT3 alone decrease the ratio compared to unchanged Bcl2/Bax ratio of similar treatment
with αT alone. Similar treatment of γT3 decreased p53 expression and activates p38 MAPK phosphorylation, whereas αT did not
alter its expression compared to H2O2-treated cells. Treating neurons with only γT3 or αT increased the expression of Bax, Bcl-2, p53, and p38 MAPK compared to
control with γT3 exerting stronger expression for proteins involved than αT. In conclusion, low doses of γT3 and αT confer
neuroprotection to H2O2-treated neurons via their antioxidant mechanism but γT3 has stronger pro-apoptosis tendency than αT by activating molecules
involved in the neuronal apoptotic pathway in the absence of H2O2. 相似文献