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41.
Tyler M. Sharp Brenda Rivera García Janice Pérez-Padilla Renee L. Galloway Marta Guerra Kyle R. Ryff Dana Haberling Sharada Ramakrishnan Sean Shadomy Dianna Blau Kay M. Tomashek William A. Bower 《PLoS neglected tropical diseases》2016,10(2)
Background
Leptospirosis is a potentially fatal bacterial zoonosis that is endemic throughout the tropics and may be misdiagnosed as dengue. Delayed hospital admission of leptospirosis patients is associated with increased mortality.Methodology/Principal Findings
During a concurrent dengue/leptospirosis epidemic in Puerto Rico in 2010, suspected dengue patients that tested dengue-negative were tested for leptospirosis. Fatal and non-fatal hospitalized leptospirosis patients were matched 1:1–3 by age. Records from all medical visits were evaluated for factors associated with fatal outcome. Among 175 leptospirosis patients identified (4.7 per 100,000 residents), 26 (15%) were fatal. Most patients were older males and had illness onset during the rainy season. Fatal case patients first sought medical care earlier than non-fatal control patients (2.5 vs. 5 days post-illness onset [DPO], p < 0.01), but less frequently first sought care at a hospital (52.4% vs. 92.2%, p < 0.01). Although fatal cases were more often diagnosed with leptospirosis at first medical visit (43.9% vs. 9.6%, p = 0.01), they were admitted to the hospital no earlier than non-fatal controls (4.5 vs. 6 DPO, p = 0.31). Cases less often developed fever (p = 0.03), but more often developed jaundice, edema, leg pain, hemoptysis, and had a seizure (p ≤ 0.03). Multivariable analysis of laboratory values from first medical visit associated with fatal outcome included increased white blood cell (WBC) count with increased creatinine (p = 0.001), and decreased bicarbonate with either increased WBC count, increased creatinine, or decreased platelet count (p < 0.001).Conclusions/Significance
Patients with fatal leptospirosis sought care earlier, but were not admitted for care any earlier than non-fatal patients. Combinations of routine laboratory values predictive of fatal outcome should be considered in admission decision-making for patients with suspected leptospirosis. 相似文献42.
Henrique Roman Ramos Inácio de Loiola M. Junqueira-de-Azevedo Juliana Branco Novo Karen Castro Clara Guerra Duarte Ricardo A. Machado-de-ávila Carlos Chavez-Olortegui Paulo Lee Ho 《PLoS neglected tropical diseases》2016,10(3)
BackgroundEnvenoming by coral snakes (Elapidae: Micrurus), although not abundant, represent a serious health threat in the Americas, especially because antivenoms are scarce. The development of adequate amounts of antielapidic serum for the treatment of accidents caused by snakes like Micrurus corallinus is a challenging task due to characteristics such as low venom yield, fossorial habit, relatively small sizes and ophiophagous diet. These features make it difficult to capture and keep these snakes in captivity for venom collection. Furthermore, there are reports of antivenom scarcity in USA, leading to an increase in morbidity and mortality, with patients needing to be intubated and ventilated while the toxin wears off. The development of an alternative method for the production of an antielapidic serum, with no need for snake collection and maintenance in captivity, would be a plausible solution for the antielapidic serum shortage.ConclusionHere we describe that the genetic immunisation with a synthetic multiepitope gene followed by booster doses with recombinant protein is a promising approach to develop an alternative antielapidic serum against M. corallinus venom without the need of collection and the very challenging maintenance of these snakes in captivity. 相似文献
43.
Development and validation of a new dynamic computer‐controlled model of the human stomach and small intestine 下载免费PDF全文
44.
45.
Intense Chiral Optical Phenomena in Racemic Polymers by Cocrystallization With Chiral Guest Molecules: A Brief Overview 下载免费PDF全文
This review is devoted to the chiral optical behavior of films of racemic polymers whose chirality is induced by cocrystallization with nonracemic (also temporary) guest molecules. We provide examples of macromolecular amplification of chirality, produced by molecular and supramolecular mechanisms, on industrially relevant polymers like poly(2,6‐dimethyl‐1,4‐phenylene)oxide (PPO) and syndiotactic polystyrene (s‐PS). Chirality 28:29–38, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
46.
47.
Taxol is an anticancer drug that triggers apoptosis in a wide spectrum of cancers such as ovarian, breast, lung, head and neck, and bladder carcinoma by both caspase-dependent and -independent apoptosis mechanisms. However, the exact signaling pathways involved in taxol-induced apoptosis strongly depend on the cellular background and they are not completely established yet. In this study we demonstrate that taxol induces caspase-3-independent apoptosis in NIH3T3 cells by a calpain-mediated mechanism. Taxol treatment produced changes in the mitochondrial membrane potential (Delta Psi m) which could be responsible of Ca(2+) release from the mitochondria and the consequent calpain activation. Interestingly, we show that calpain produced proteolysis of caspase-3 and demonstrate that, accordingly, calpain inhibition increased taxol-induced apoptosis. In addition, we reveal that poly (ADP-ribose) polymerase (PARP) was processed by calpain in taxol-treated cells and by caspase-3 after calpain inhibition. In conclusion, these results demonstrate for the first time that calpain could play an important role modulating taxol-induced apoptosis. Further studies are needed to address the potentiality of inducing apoptosis by a combined use of taxol and calpain inhibitors in cells with increased calpain activity. 相似文献
48.
Several chromosome types have been recognized in Citrus and related genera by chromomycin A3 (CMA) banding patterns and fluorescent in situ hybridization (FISH). They can be used to characterize cultivars and species
or as markers in hybridization and backcrossing experiments. In the present work, characterization of six cultivars of P. trifoliata (“Barnes”, “Fawcett”, “Flying Dragon”, “Pomeroy”, “Rubidoux”, “USDA”) and one P. trifoliata × C. limonia hybrid was performed by sequential analyses of CMA banding and FISH using 5S and 45S rDNA as probes. All six cultivars showed
a similar CMA+ banding pattern with the karyotype formula 4B + 8D + 6F. The capital letters indicate chromosomal types: B, a chromosome
with one telomeric and one proximal band; D, with only one telomeric band; F, without bands. In situ hybridization labeling
was also similar among cultivars. Three chromosome pairs displayed a closely linked set of 5S and 45S rDNA sites, two of them
co-located with the proximal band of the B type chromosomes (B/5S-45S) and the third one co-located with the terminal band
of a D pair (D/5S-45S). The B/5S-45S chromosome has never been found in any citrus accessions investigated so far. Therefore,
this B chromosome can be used as a marker to recognize the intergeneric Poncirus × Citrus hybrids. The intergeneric hybrid analyzed here displayed the karyotype formula 4B + 8D + 6F, with two chromosome types B/5S-45S
and two D/5S-45S. The karyotype formula and the presence of two B/5S-45S chromosomes clearly indicate that the plant investigated
is a symmetric hybrid. It also demonstrates the suitability of karyotype analyses to differentiate zygotic embryos or somatic
cell fusions involving trifoliate orange germplasm.
During the submission of this paper, we analyzed 25 other citrus cultivars with the same methodology and we found that the
chromosome marker reported here can indeed distinguish Poncirus trifoliata from grapefruits, pummelos, and one variegated access of Citrus, besides the previously reported access of limes, limons, citrons, and sweet-oranges. However, among 14 mandarin cultivars,
two of them displayed a single B/5S-45S chromosome, whereas in Citrus hystrix D.C., a far related species belonging to the Papeda subgenus, this chromosome type was found in homozygosis. Since these two mandarin cultivars are probably of hybrid origin,
we assume that for almost all commercial cultivars and species of the subgenus Citrus this B type chromosome is a useful genetic marker. 相似文献
49.
Bush CR Havens JM Necela BM Su W Chen L Yanagisawa M Anastasiadis PZ Guerra R Luxon BA Thompson EA 《The Journal of biological chemistry》2007,282(32):23387-23401
50.
Maria Raffaella Greco Emeline Bon Rosa Rubino Lorenzo Guerra Manuel Bernabe-Garcia Stefania Cannone Maria-Luisa Cayuela Loredana Ciaccia Séverine Marionneau-Lambot Thibauld Oullier Gaëlle Fromont Roseline Guibon Sébastien Roger Stephan Joel Reshkin Rosa Angela Cardone 《生物化学与生物物理学报:疾病的分子基础》2019,1865(1):26-37
Metastatic cancer cells are highly plastic for the expression of different tumor phenotype hallmarks and organotropism. This plasticity is highly regulated but the dynamics of the signaling processes orchestrating the shift from one cell phenotype and metastatic organ pattern to another are still largely unknown. The scaffolding protein NHERF1 has been shown to regulate the expression of different neoplastic phenotypes through its PDZ domains, which forms the mechanistic basis for metastatic organotropism. This reprogramming activity was postulated to be dependent on its differential phosphorylation patterns. Here, we show that NHERF1 phosphorylation on S279/S301 dictates several tumor phenotypes such as in vivo invasion, NHE1-mediated matrix digestion, growth and vasculogenic mimicry. Remarkably, injecting mice with cells having differential NHERF1 expression and phosphorylation drove a shift from the predominantly lung colonization (WT NHERF1) to predominately bone colonization (double S279A/S301A mutant), indicating that NHERF1 phosphorylation also acts as a signaling switch in metastatic organotropism. 相似文献