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51.
Information about the prevalence of malarial anemia in areas of low-malaria transmission intensity, like Latin America, is scarce. To characterize the malaria-related anemia, we evaluated 929 malaria patients from three sites in Colombia during 2011–2013. Plasmodium vivax was found to be the most prevalent species in Tierralta (92%), whereas P. falciparum was predominant in Tumaco (84%) and Quibdó (70%). Although severe anemia (hemoglobin < 7 g/dL) was almost absent (0.3%), variable degrees of non-severe anemia were observed in 36.9% of patients. In Tierralta, hemoglobin levels were negatively associated with days of illness. Moreover, in Tierralta and Quibdó, the number of previous malaria episodes and hemoglobin levels were positively associated. Both Plasmodium species seem to have similar potential to induce malarial anemia with distinct cofactors at each endemic setting. The target age in these low-transmission settings seems shifting toward adolescents and young adults. In addition, previous malaria experience seems to induce protection against anemia development. Altogether, these data suggest that early diagnosis and prompt treatment are likely preventing more frequent and serious malaria-related anemia in Colombia.  相似文献   
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Dystrophin gene deletions account for up to 68% of all Duchenne (DMD) and Becker (BMD) muscular dystrophy mutations. In affected males, these deletions can be detected easily using multiplex PCR tests which monitor for exon presence. In addition, quantitative dosage screening can discriminate female carriers. We previously analyzed multiplex PCR products by gel electrophoresis and quantitation of fluorescently labeled primers with the Gene Scanner? in order to test carrier status. These multiplex PCR protocols detect DMD gene deletions adequately, but require up to 18 pairs of fluorochrome-labeled primers. We previously described two alternative fluorescent labeling strategies, each with approximately 1,000-fold greater sensitivity than ethidium bromide staining, which can be used to quantify the products of multiplex PCR. The first method uses the DNA intercalating thiazole orange dye TOTO-1 to stain PCR products after 20 cycles. In the second method, fluorescein-12,2′-dUTP is incorporated into products during PCR as a fluorescent tag for subsequent quantitative dosage studies. Both methods label all multiplexed exons including the 506 bp exon 48 fragment that is difficult to detect and quantify by standard ethidium bromide staining. Using this approach, we determined DMD/BMD carrier status in 24 unrelated families using a fluorescent fragment analyzer. Analysis of fluorochrome-labeled PCR products facilitates quantitative multiplex PCR for gene-dosage analysis. © 1993 Wiley-Liss, Inc.  相似文献   
53.
Cancer is a major adverse outcome of solid organ transplantation, and risks are especially high for malignancies caused by viral infections. HHV‐8 is the etiologic agent of Kaposi´s sarcoma (KS). We report a case of visceral KS occurring in a 15‐year‐old patient after lung transplantation. The evolution was dramatically fast and interestingly, KS lesions were diffusely observed, but not in the skin. The autopsy showed the presence of numerous tumoral lesions in many organs. Microscopically, they all had very similar features, regardless of the organ affected. KS presented without cutaneous involvement. The girl was not tested for HHV‐8 prior to transplantation as it was not part of our protocol. The donor was negative. The aim of the report is to alert other teams, especially those working in pediatrics, about this rare but potential complication in the setting of solid organ transplantation.  相似文献   
54.
GPR40 and GPR120 are G-protein-coupled receptors that can be activated by medium- and long-chain fatty acids. GPR40 is expressed in several breast cancer cell lines and its stimulation with oleic acid (OA) induces cell proliferation. However, the signal transduction pathways activated by OA have not been studied in detail. Our results demonstrate that both GPR40 and GPR120 are expressed in MCF-7 cells. Stimulation of MCF-7 and MDA-MB-231 cells with OA promoted the phosphorylation of ERK1/2 at Thr-202 and Tyr-204 and the formation of AP-1-DNA complex in a fashion dependent of Src kinase activity and EGFR transactivation. Furthermore, proliferation induced by OA is restricted to breast cancer cells in a fashion dependent of ERK1/2 activation and matrix metalloproteinases. In summary, our data indicate that proliferation induced by OA is restricted to breast cancer cells, and that ERK1/2 activation and AP-1-DNA complex formation are mediated by Src family kinases and transactivation of EGFR.  相似文献   
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Human Norovirus is currently the main viral cause of acute gastroenteritis (AGEs) in most countries worldwide. Nearly 50 years after the discovery of the “Norwalk virus” by Kapikian and colleagues, the scientific and medical community continue to generate new knowledge on the full biological and disease spectrum of Norovirus infection. Nevertheless, several areas remain incompletely understood due to the serious constraints to effectively replicate and propagate the virus. Here, we present a narrated historic perspective and summarize our current knowledge, including insights and reflections on current points of interest for a broad medical community, including clinical and molecular epidemiology, viral–host–microbiota interactions, antivirals, and vaccine prototypes. We also include a reflection on the present and future impacts of the COVID-19 pandemic on Norovirus infection and disease.  相似文献   
57.
Mitochondria are highly integrated organelles that are crucial to cell adaptation and mitigating adverse physiology. Recent studies demonstrate that fundamental signal transduction pathways incorporate mitochondrial substrates into their biological programs. Reversible phosphorylation is emerging as a useful mechanism to modulate mitochondrial function in accordance with cellular changes. Critical serine/threonine protein kinases, such as the c‐Jun N‐terminal kinase (JNK), protein kinase A (PKA), PTEN‐induced kinase‐1 (PINK1), and AMP‐dependent protein kinase (AMPK), readily translocate to the outer mitochondrial membrane (OMM), the interface of mitochondria‐cell communication. OMM protein kinases phosphorylate diverse mitochondrial substrates that have discrete effects on organelle dynamics, protein import, respiratory complex activity, antioxidant capacity, and apoptosis. OMM phosphorylation events can be tempered through the actions of local protein phosphatases, such as mitogen‐activated protein kinase phosphatase‐1 (MKP‐1) and protein phosphatase 2A (PP2A), to regulate the extent and duration of signaling. The central mediators of OMM signal transduction are the scaffold proteins because the relative abundance of these accessory proteins determines the magnitude and duration of a signaling event on the mitochondrial surface, which dictates the biological outcome of a local signal transduction pathway. The concentrations of scaffold proteins, such as A‐kinase anchoring proteins (AKAPs) and Sab (or SH3 binding protein 5—SH3BP5), have been shown to influence neuronal survival and vulnerability, respectively, in models of Parkinson's disease (PD), highlighting the importance of OMM signaling to health and disease. Despite recent progress, much remains to be discovered concerning the mechanisms of OMM signaling. Nonetheless, enhancing beneficial OMM signaling events and inhibiting detrimental protein‐protein interactions on the mitochondrial surface may represent highly selective approaches to restore mitochondrial health and homeostasis and mitigate organelle dysfunction in conditions such as PD.  相似文献   
58.
Surgical site infections (SSIs) impact significantly on patient mortality, morbidity and quality of life. They also incur financial costs on the healthcare system, although the total cost may vary depending on the severity of the infection. Antisepsis, aseptic technique and skin preparation are important concepts in the preventative strategies to reduce the risks of SSIs. This article reviews these concepts and the role they play in the patient's perioperative journey.  相似文献   
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The present work describes the abrupt emergence of Klebsiella pneumoniae carbapenemase (KPC) and characterizes the first 79 KPC-producing enterobacteria from Argentina (isolated from 2006 to 2010). The emergence of blaKPC-2 was characterized by two patterns of dispersion: the first was the sporadic occurrence in diverse enterobacteria from distant geographical regions, harbouring plasmids of different incompatibility groups and blaKPC-2 in an unusual genetic environment flanked by ISKpn8blaTEM-1 and ISKpn6-like. blaKPC-2 was associated with IncL/M transferable plasmids; the second was the abrupt clonal spread of K. pneumoniae ST258 harbouring blaKPC-2 in Tn4401a.  相似文献   
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