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Ana Lopez Alonso 《Platelets》2015,26(4):317-323
Abstract

While the interactions between Gram-positive bacteria and platelets have been well characterized, there is a paucity of data on the interaction between other pathogens and platelets. However, thrombocytopenia is a common feature with many infections especially viral hemorrhagic fever. The little available data on these interactions indicate a similarity with bacteria-platelet interactions with receptors such as FcγRIIa and Toll-Like Receptors (TLR) playing key roles with many pathogens. This review summarizes the known interactions between platelets and pathogens such as viruses, fungi and parasites.  相似文献   
3.
Alterations in autophagy are increasingly being recognized in the pathogenesis of proteinopathies like Alzheimer's disease (AD). This study was conducted to evaluate whether melatonin treatment could provide beneficial effects in an Alzheimer model related to tauopathy by improving the autophagic flux and, thereby, prevent cognitive decline. The injection of AAV‐hTauP301L viral vectors and treatment/injection with okadaic acid were used to achieve mouse and human ex vivo, and in vivo tau‐related models. Melatonin (10 μmol/L) impeded oxidative stress, tau hyperphosphorylation, and cell death by restoring autophagy flux in the ex vivo models. In the in vivo studies, intracerebroventricular injection of AAV‐hTauP301L increased oxidative stress, neuroinflammation, and tau hyperphosphorylation in the hippocampus 7 days after the injection, without inducing cognitive impairment; however, when animals were maintained for 28 days, cognitive decline was apparent. Interestingly, late melatonin treatment (10 mg/kg), starting once the alterations mentioned above were established (from day 7 to day 28), reduced oxidative stress, neuroinflammation, tau hyperphosphorylation, and caspase‐3 activation; these observations correlated with restoration of the autophagy flux and memory improvement. This study highlights the importance of autophagic dysregulation in tauopathy and how administration of pharmacological doses of melatonin, once tauopathy is initiated, can restore the autophagy flux, reduce proteinopathy, and prevent cognitive decline. We therefore propose exogenous melatonin supplementation or the development of melatonin derivatives to improve autophagy flux for the treatment of proteinopathies like AD.  相似文献   
4.

Objectives

To determine the incidence of incisional hernia (IH) in the extraction incision (EI) in colorectal resection for cancer. To analyze whether the location of the incision has any relationship with the incidence of hernias and whether mesh could be useful for prevention in high-risk patients.

Methods

Retrospective review of the colon and rectal surgery database from January 2015 to December 2016. Data were classified into 2 groups, transverse (TI) and midline incision (MI), and the latter was divided into 2 subgroups (mesh [MIM] and suture [MIS]). Patients were classified using the HERNIAscore. Hernias were diagnosed by clinical and/or CT examination.

Results

A total of 182 out of 210 surgical patients were included. After a median follow-up of 13.0 months, 39 IH (21.9%) were detected, 23 of which (13.4%) were in the EI; their frequency was lower in the TI group (3.4%) and in the MIM group (5.9%) than in the MIS group (29.5%; p = 0.007). The probability of developing IH in the MIS group showed an OR = 11.7 (95%CI: 3.3-42.0) compared to the TI group and 4.3 (IC 95%: 1.1-16.3) versus the MIM group.

Conclusions

The location of the incision is relevant to avoid incisional hernias. Transverse incisions should be used as the first option. When a midline incision is needed, a prophylactic mesh could be considered in high risk patients because it is safe and associated with low morbidity.  相似文献   
5.
This study was designed to characterize a collection of 60 enteropathogenic Escherichia coli (EPEC) isolates from diarrheic feces of patients in the Ribeirão Preto metropolitan area regarding different phenotypic and molecular features. We examined antibiotic resistance profiles, occurrence of virulence factors‐encoding genes, intimin subtypes and the correlation of serotypes among typical (tEPEC) and atypical (aEPEC) EPEC isolates. The results demonstrated that atypical EPEC was more heterogeneous than typical EPEC concerning the characteristics investigated and 45.2% do not belong to classical EPEC serogroups. Intimin subtype β was the most frequent among the EPEC isolates (46.7%), being detected in both tEPEC and aEPEC. The majority of aEPEC isolates presented localized adherence‐like (LAL) pattern to HEp‐2 cells, although aEPEC isolates displaying diffuse adherence (DA) or non‐adherent were also detected. High prevalence of antimicrobial resistance was found for ampicillin, cephalothin, sulfonamide and tetracycline. In general, tEPEC isolates were more resistant to the antimicrobials tested than aEPEC isolates.  相似文献   
6.
Enterococcus faecalis (E. faecalis) is a common cause of nosocomial infection in immunocompromised patients. The presence and dissemination of high‐risk clonal complexes, such as CC2, is an ongoing problem in hospitals. The aim of this work was to characterize 24 E. faecalis isolates from ICU patients undergoing selective decontamination of the digestive tract (SDD) by phenotypical (antimicrobial susceptibility) and genotypical (presence of virulence genes, RAPD‐PCR and MLST) methods. Our results showed high prevalence of the ST6 E. faecalis clone (91.6%), especially adapted to the hospital environment, with a multidrug resistance pattern and a multitude of putative virulence genes. In addition, ST179 (4.2%) and ST191 (4.2%) were detected. By RAPD–PCR analysis, the 22 isolates identified as ST6 showed six different DNA patterns, while the two remaining isolates, ST179 and ST191, showed two additional profiles. CC2 is a known clonal complex with high adaptability to hospital environment and worldwide distribution. The high prevalence of the ST6 clone in the studied population could be related to the presence of gentamicin in the SDD mixture since most strains were gentamicin resistant. Consequently, strict surveillance should be applied for rapid detection and control of this clone to prevent future spread outside the ICU.  相似文献   
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8.
IntroductionPeople with Down syndrome (DS) have high respiratory morbidity, evaluating their respiratory health with standardized, objective tests is desirable. Thus, the objective of this study was to evaluate the technical quality of Pulmonary Function Tests (PFTs) to determine which ones are most suitable for this population.MethodsParticipants included children, teenagers and adults with DS, 5 years of age or older (n = 302). The technical quality of the impulse oscillometry system (IOS), forced spirometry, lung-diffusing capacity for carbon monoxide (DLCO), and 6-min walk test (6MWT) were analyzed by age group. Capnography and pulse oximetry were included in the study. Technical quality was determined on the basis of current international PFTs standards.ResultsFifty-one percent of participants were males. A total of 184 participants (71%) who completed the IOS fulfilled the quality criteria, while 210 (70%) completed the 6MWT. Performance on forced spirometry and DLCO was poor. All pulse oximetries and 96% percent heart rates obtained had good quality, but exhaled carbon dioxide (PetCO2) and respiratory rate (RR) showed deficient repeatability.ConclusionsIOS appears to be the most reliable instrument for evaluating lung mechanics in individuals with DS.  相似文献   
9.
正The emerging role of gut microbiota as a key player in the development of neurodegenerative disorders:Mammals have evolved togetherwithcommensalmicrobiotatoestablishasymbioticrelationship in which they regulate reciprocally by synthesizing and responding to several common chemical substances. In this regard, gut microbiota  相似文献   
10.
We report on 3 patients with pseudoathetosis, which are involuntary, slow, writhing movements due to loss of proprioception.  相似文献   
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