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51.

Background

Platelets with high hemostatic activity play an important role in the pathophysiology of coronary artery disease(CAD) and mean platelet volume(MPV) has been proposed as an indicator of platelet reactivity. Thus, MPV may emerge as a potential marker of CAD risk. The aim of this study was to conduct a systematic review and meta-analysis comparing mean difference in MPV between patients with CAD and controls and pooling the odds ratio of CAD in those with high versus low MPV.

Methods

Medline and Scopus databases were searched up to 12 March 2013. All observational studies that considered MPV as a study's factor and measured CAD as an outcome were included. Two reviewers independently selected the studies and extracted the data.

Results

Forty studies were included in this meta-analysis. The MPV was significantly larger in patients with CAD than controls with the unstandardized mean difference of 0.70 fL (95% CI: 0.55, 0.85). The unstandardized mean difference of MPV in patients with acute coronary event and in patients with chronic stable angina was 0.84 fL (95% CI: 0.63, 1.04) and 0.46 fL (95% CI: 0.11, 0.81) respectively. Patients with larger MPV (≥ 7.3 fL) also had a greater odds of having CAD than patients with smaller MPV with a pooled odds ratio of 2.28 (95% CI: 1.46, 3.58).

Conclusion

Larger MPV was associated with CAD. Thus, it might be helpful in risk stratification, or improvement of risk prediction if combining it with other risk factors in risk prediction models.  相似文献   
52.
The PET tracer [11C]5-hydroxytryptophan ([11C]5-HTP), which is converted to [11C]5-hydroxytryptamine ([11C]5-HT) by aromatic amino acid decarboxylase (AADC), is thought to measure 5-HT synthesis rates. But can we measure these synthesis rates by kinetic modeling of [11C]5-HTP in rat? Male rats were scanned with [11C]5-HTP (60 minutes) after different treatments. Scans included arterial blood sampling and metabolite analysis. 5-HT synthesis rates were calculated by a two-tissue compartment model (2TCM) with irreversible tracer trapping or Patlak analysis. Carbidopa (inhibitor peripheral AADC) dose-dependently increased [11C]5-HTP brain uptake, but did not influence 2TCM parameters. Therefore, 10 mg/kg carbidopa was applied in all subsequent study groups. These groups included treatment with NSD 1015 (general AADC inhibitor) or p-chlorophenylalanine (PCPA, inhibitor of tryptophan hydroxylase, TPH). In addition, the effect of a low-tryptophan (Trp) diet was investigated. NSD 1015 or Trp depletion did not affect any model parameters, but PCPA reduced [11C]5-HTP uptake, and the k3. This was unexpected as NSD 1015 directly inhibits the enzyme converting [11C]5-HTP to [11C]5-HT, suggesting that trapping of radioactivity does not distinguish between parent tracer and its metabolites. As different results have been acquired in monkeys and humans, [11C]5-HTP-PET may be suitable for measuring 5-HT synthesis in primates, but not in rodents.  相似文献   
53.
Structural alterations of NUTM1 were originally thought to be restricted to poorly differentiated carcinomas with variable squamous differentiation originating in the midline organs of children and adolescents. Termed NUT carcinomas (NCs), they were defined by a t(15;19) chromosomal rearrangement that was found to result in a BRD4‐NUTM1 gene fusion. However, the use of DNA and RNA‐based next‐generation sequencing has recently revealed a multitude of new NUTM1 fusion partners in a diverse array of neoplasms including sarcoma‐like tumors, poromas, and acute lymphoblastic leukemias (ALLs) that we propose to call NUTM1‐rearranged neoplasms (NRNs). Intriguingly, the nosology of NRNs often correlates with the functional classification of the fusion partner, suggesting different oncogenic mechanisms within each NRN division. Indeed, whereas NCs are characterized by their aggressiveness and intransigence to standard therapeutic measures, the more positive clinical outcomes seen in some sarcoma and ALL NRNs may reflect these mechanistic differences. Here we provide a broad overview of the molecular, nosological, and clinical features in these newly discovered neoplastic entities. We describe how aberrant expression of NUTM1 due to fusion with an N‐terminal DNA/chromatin‐binding protein can generate a potentially powerful chromatin modifier that can give rise to oncogenic transformation in numerous cellular contexts. We also conclude that classification, clinical behavior, and therapeutic options may be best defined by the NUTM1 fusion partner rather than by tumor morphology or immunohistochemical profile.  相似文献   
54.
55.
Background The validity of circulating tumour DNA (ctDNA) as an indicator of disease progression compared to medical imaging in patients with metastatic melanoma requires detailed evaluation.Methods Here, we carried out a retrospective ctDNA analysis of 108 plasma samples collected at the time of disease progression. We also analysed a validation cohort of 66 metastatic melanoma patients monitored prospectively after response to systemic therapy.Results ctDNA was detected in 62% of patients at the time of disease progression. For 67 patients that responded to treatment, the mean ctDNA level at progressive disease was significantly higher than at the time of response (P < 0.0001). However, only 30 of these 67 (45%) patients had a statistically significant increase in ctDNA by Poisson test. A validation cohort of 66 metastatic melanoma patients monitored prospectively indicated a 56% detection rate of ctDNA at progression, with only two cases showing increased ctDNA prior to radiological progression. Finally, a correlation between ctDNA levels and metabolic tumour burden was only observed in treatment naïve patients but not at the time of progression in a subgroup of patients failing BRAF inhibition (N = 15).Conclusions These results highlight the low efficacy of ctDNA to detect disease progression in melanoma when compared mainly to standard positron emission tomography imaging.Subject terms: Tumour biomarkers, Biomarkers  相似文献   
56.
ObjectiveBody mass index (BMI), uric acid, diabetes mellitus, and hypertension are risk factors for reduced kidney function and are associated with fetuin-A levels, but their causal pathways remain unclear. The objective of this study was to investigate this knowledge gap.MethodsA repeated cross-sectional design was used to assess causal pathway effects of fetuin-A on the estimated glomerular filtration rate (eGFR), which is mediated through BMI, uric acid, diabetes mellitus, and hypertension.ResultsAmong 2305 participants, the mean eGFR at baseline decreased from 98.7 ± 23.6 mL/minute/1.73 m2 in 2009 to 92.4 ± 22.9 mL/minute/1.73 m2 in 2014. Fetuin-A was significantly associated with eGFR , suggesting that increasing fetuin-A levels predict a decrease in eGFR. Additionally, the indirect effect of fetuin-A on eGFR, as assessed through BMI, was also significant. The effects of fetuin-A on eGFR through other mediation pathways showed variable results.ConclusionsOur study revealed a possible role of fetuin-A in the etiology of declining renal function through mediating body mass index, uric acid, diabetes mellitus, and hypertension via complex causal pathways. Further studies to clarify these mediated effects are recommended.  相似文献   
57.
R C McEvoy  P E Leung 《Diabetes》1983,32(9):852-857
Syngeneic fetal rat islets were isolated and transplanted into alloxan-diabetic inbred male Lewis rats. The effect of transplantation of islets into the cerebral ventricles on the diabetic state of the recipients was compared with that of the conventional transplantation of islets homeotypically into the liver via the portal vein. Fourteen of fourteen rats surviving after stereotaxic implantation of islets into the ventricles returned to normoglycemia; normoglycemia has been maintained for up to 34 wk. Glucose tolerance tests revealed an improved, although not completely normalized, pattern. Histologic examination of the brains of these recipients revealed clusters of intact islets in the ventricle. These data provided a physiologic basis for further investigation of the immunologically privileged nature of the intraventricular space as a site for implantation of allogeneic pancreatic islets. Islets from Wistar-Furth rats (major histocompatibility difference) or Fischer 344 rats (minor histocompatibility difference) were transplanted into the ventricles of alloxan-diabetic Lewis rats. There were only small and unsustained changes in body weight and blood and urine glucose of any of the rats receiving the allogeneic islets. Histologic examination of the ventricles of these rats 3 wk after transplantation revealed only glial scar tissue. These data suggest that the cerebral ventricles cannot serve as a privileged site for islet transplantation, at least using the type of islet preparation employed in these experiments.  相似文献   
58.
COUNT ME IN:     
Many students with mental handicaps fail to master basic counting and number skills, even after 10 years' schooling. It is suggested that making numbers meaningful, simplifying tasks, and making learning fun is essential. The use of number games, introduced in a planned way ensuring success at every stage, can aid the learning process.  相似文献   
59.
Immature avulsed teeth are not usually treated with pulp revascularization because of the possibility of complications. However, this therapy has shown success in the treatment of immature teeth with periapical lesions. This report describes the case of an immature replanted tooth that was successfully treated by pulp revascularization. An 8‐year‐old boy suffered avulsion on his maxillary left lateral incisor. The tooth showed incomplete root development and was replanted after 30 minutes. After diagnosis, revascularization therapy was performed by irrigating the root canal and applying a calcium hydroxide paste and 2% chlorhexidine gel for 21 days. In the second session, the intracanal dressing was removed and a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate was placed as a cervical barrier at the entrance of the root canal and the crown was restored. During the follow‐up period, periapical repair, apical closure and calcification in the apical 4 mm of the root canal was observed. An avulsed immature tooth replanted after a brief extra‐alveolar period and maintained in a viable storage medium may be treated with revascularization.  相似文献   
60.

Introduction

Septic shock is a major cause of morbidity and mortality throughout the world. Unfortunately, the optimal fluid management of septic shock is unknown and currently is empirical.

Methods

A retrospective analysis was performed at Barnes-Jewish Hospital (St. Louis, Missouri). Consecutive patients (n = 325) hospitalized with septic shock who had echocardiographic examinations performed within 24 hours of shock onset were enrolled.

Results

A total of 163 (50.2%) patients with septic shock died during hospitalization. Non-survivors had a significantly larger positive net fluid balance within the 24 hour window of septic shock onset (median (IQR): 4,374 ml (1,637 ml, 7,260 ml) vs. 2,959 ml (1,639.5 ml, 4,769.5 ml), P = 0.004). The greatest quartile of positive net fluid balance at 24 hours and eight days post-shock onset respectively were found to predict hospital mortality, and the greatest quartile of positive net fluid balance at eight days post-shock onset was an independent predictor of hospital mortality (adjusted odds ratio (AOR), 1.66; 95% CI, 1.39 to 1.98; P = 0.004). Survivors were significantly more likely to have mild left ventricular dysfunction as evaluated by bedside echocardiography and non-survivors had slightly elevated left ventricular ejection fraction, which was also found to be an independent predictor of outcome.

Conclusions

Our data confirms the importance of fluid balance and cardiac function as outcome predictors in patients with septic shock. A clinical trial to determine the optimal administration of intravenous fluids to patients with septic shock is needed.  相似文献   
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