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11.

Introduction

There is growing acceptance that the detrusor muscle is not silent during the filling phase of the micturition cycle but displays low-amplitude phasic contractions that have been associated with urinary urgency. Unfortunately, there is currently no standardized methodology to quantify detrusor rhythm during the filling phase. Therefore, the purpose of this study was to develop an automated computer algorithm to analyze rat detrusor rhythm in a quick, accurate, and reproducible manner.

Materials and methods

Strips of detrusor smooth muscle from rats (n = 17) were placed on force transducers and subjected to escalating doses of PGE2 to generate contractile rhythm tracings. An automated computer algorithm was developed to analyze contractile frequency, amplitude, and tone on the generated rhythm tracings. Results of the automated computerized analysis were compared to human (n = 3) interpretations. Human interpreters manually counted contractions and then recounted the same data two weeks later. Intra-observer, inter-observer, and human-to-computer comparisons were performed.

Results

The computer algorithm quantified concentration-dependent changes in contractile frequency, amplitude, and tone after administration of PGE2 (10?9–10?6M). Concentration–response curves were similar for all contractile components with increases in frequency identified mainly at physiologic concentrations of PGE2 and increases in amplitude at supra-physiologic concentrations. The computer algorithm consistently over-counted the human interpreters, but with less variability. Differences in inter-observer consistency were statistically significant.

Conclusions

Our computerized algorithm accurately and consistently identified changes in detrusor muscle contractile frequency, amplitude, and tone with varying doses of PGE2. Frequency counts were consistently higher than those obtained by human interpreters but without variability or bias. Refinements of this method may allow for more standardized approach in the study of pharmacologic agents on filling phase rhythmic activity.  相似文献   
12.
In this work, nickel–cobalt alloy nanoparticles were electrodeposited on/in an electrochemically reduced nitrogen-doped graphene oxide (ErN-GO)/carbon-ceramic electrode (CCE) and the resulting nanocomposite (NiCo/ErN-GO/CCE) was evaluated as a low cost electrocatalyst for methanol and ethanol electrooxidation. Field-emission scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy were used for the physical characterization of the electrocatalyst. To study the electrochemical behavior and electrocatalytic activity of the prepared electrocatalyst towards the oxidation of methanol and ethanol in alkaline media, cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy were utilized. Electrochemical investigation of the introduced electrocatalysts (NiCo alloy and Ni nanoparticles alone electrodeposited on/in different substrates) indicated that NiCo/ErN-GO/CCE has highest activity and stability towards methanol (Jp = 88.04 mA cm−2) and ethanol (Jp = 64.23 mA cm−2) electrooxidation, which highlights its potential use as an anodic material in direct alcohol fuel cells.

NiCo alloy nanoparticles on the electrochemically reduced nitrogen-doped graphene oxide/carbon-ceramic electrode: a low cost electrocatalyst towards methanol and ethanol oxidation.  相似文献   
13.
Production of activated nano-carbon from agricultural wastes was studied in this work. To obtain the optimum production conditions by a physical activation method, influence of temperature (850, 900, 950 and 1000 °C), activation residence time (30, 60 and 90 min), and mill rotation (200, 300 and 400 rpm) were investigated using three different raw materials including walnut, almond and pistachio shells. To prepare activated nano-carbon, all the samples were heated up to the final activation temperature under a continuous steam flow of 130 cm3 min−1, and at a heating rate of 3 °C min−1, and were held at the different activation temperatures for 30, 60 and 90 minutes. BET surface area of the obtained activated carbons was measured from nitrogen adsorption data in the relative pressure range between 0 to 1. Activated nano-carbon standard indexes were evaluated according to the ASTM standard and the samples were compared. First, the cellulose raw material was heated in the carbonization furnace at 600 °C and then activated in the advanced activation furnace at a temperature between 850 to 1000 °C for 30, 60 and 90 minutes with water vapor. Ash percentage, iodine content, moisture content, specific area, elemental analysis, and FESEM were used for product characterization. The results of the analysis showed that by using the water vapor physical activation method and optimizing the parameters of this process including time and rotation of the mill up to 10 min and 400 rpm, resulted in a significant increase in specific surface area, cavity volume and the iodine number of the final product.

Production of activated nano-carbon from agricultural wastes was studied in this work.  相似文献   
14.
Angiogenesis as a novel component of inflammatory bowel disease pathogenesis   总被引:14,自引:0,他引:14  
BACKGROUND & AIMS: Angiogenesis is a critical component of neoplastic and chronic inflammatory disorders, but whether angiogenesis also occurs in inflammatory bowel disease (IBD) has yet to be established. We assessed mucosal vascularization, expression of endothelial alphaVbeta3 integrin, angiogenic factors, and their bioactivity in Crohn's disease (CD) and ulcerative colitis (UC) mucosa. METHODS: Mucosal endothelium was immunostained for CD31 and factor VIII and quantified by digital morphometry. alphaVbeta3 expression was studied in vivo by confocal microscopy and in vitro by flow cytometric analysis of human intestinal microvascular endothelial cells (HIMECs). Vascular endothelial growth factor (VEGF), interleukin (IL)-8, and bFGF levels were measured in mucosal extracts and cells and angiogenic bioactivity shown by induction of HIMEC migration and the corneal and chorioallantoic membrane angiogenesis assays. RESULTS: Microvessel density was increased in IBD mucosa. Endothelial alphaVbeta3 was strongly expressed in IBD but only sporadically in normal mucosa and was up-regulated in HIMECs by VEGF, tumor necrosis factor alpha, and bFGF. IBD mucosal extracts induced a significantly higher degree of HIMEC migration than control mucosa, and this response was mostly dependent on IL-8 and less on basic fibroblast growth factor or vascular endothelial growth factor. Compared with normal mucosa, IBD mucosal extracts induced a potent angiogenic response in both the corneal and chorioallantoic membrane assays. CONCLUSIONS: These results provide morphological, phenotypic and functional evidence of potent angiogenic activity in both CD and UC mucosa, indicating that the local microvasculature undergoes an intense process of inflammation-dependent angiogenesis. Thus, angiogenesis appears to be an integral component of IBD pathogenesis, providing the practical and conceptual framework for anti-angiogenic therapies in IBD.  相似文献   
15.
16.
17.

Introduction

Thrombosis is frequently observed in Galen malformation, but propagation of thrombosis resulting in the disappearance of the aneurysmal malformation is a very rare clinical condition.

Case report

A rare case of spontaneous regression and disappearance of the vein of Galen aneurysmal malformation (VoGAM) in a pediatric patient with repeated generalized seizure, increased head circumference, and congestive heart failure is recorded. The course of regression from infancy to 8 years of age has been depicted. Radiological studies initially demonstrated VoGAM complicated by an intra-cerebral hemorrhage and hydrocephalus, which later underwent spontaneous regression. Long-term clinical and radiological follow-up is presented.

Discussion

Different conditions including hemodynamic alteration, compression of adjacent hematoma, and narrowing of related vascular structures have been described to cause thrombosis of VoGAM. The relevant literature to address possible mechanism is reviewed.
  相似文献   
18.
19.
Production of abnormal hemoglobin (HbS) in sickle‐cell disease (SCD) results in its polymerization in deoxygenated conditions and in sickled‐RBC formation. Dense RBCs (DRBCs), defined as density >1.11 and characterized by increased rigidity are absent in normal AA subjects, but present at percentages that vary of a patient to another remaining stable throughout adulthood for each patient. Polymerized HbS has reduced affinity for oxygen, demonstrated by the rightward shift of the oxygen‐dissociation curve, leading to disturbances in oxygen transport. Ninety‐two SCD patients' total RBCs were separated into LightDRBC (LRBC) (d < 1.11 g/mL) and DRBC fractions. Venous blood partial oxygen pressure and RBC‐fraction–deoxygenation and –reoxygenation Hb–oxygen‐equilibrium curves were determined. All patients took a 6‐minute walking test (6MWT); 10 had results before and after >6 months on hydroxyurea. 6MWT time with SpO2 < 88% (TSpO2 < 88) assessed the physiological impact of exertion. Elevated mean corpuscular hemoglobin (Hb) concentrations, decreased %HbF, and 2,3‐bisphosphoglycerates in DRBCs modulated Hb–oxygen affinity. Deoxygenation and reoxygenation Hb–oxygen equilibrium curves differed between normal Hb AA and SS RBCs and between LRBCs and DRBCs, with rightward shifts confirming HbS‐polymerization's role in affinity loss. In bivariate analyses, 50% Hb saturation correlated positively with %DRBCs (P < 0.0001, r2 = 0.34) and negatively with %HbF (P < 0.0001, r2 = 0.25). The higher the %DRBCs, the longer the TSpO288 (P = 0.04). Hydroxyurea was associated with significantly shorter TSpO2 < 88 (P = 0.01). We report that the %DRBCs directly affects SCD patients' SpO2 during exertion; hydroxyurea improves oxygen affinity and lowers the %DRBCs. Am. J. Hematol. 91:1008–1013, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
20.
BACKGROUND: It has been suggested that health professionals may discard measurement of hip circumference from public health screening efforts. Before discarding the hip circumference in epidemiological surveys, it is important to consider whether any important information is likely to be lost. OBJECTIVE: To evaluate the relationship between hip circumference and metabolic risk factors in an urban adult population of Tehranian women. DESIGN: In this population-based cross-sectional study, a representative sample of 5720 women aged 18-74 years, were included. Demographic data was collected; anthropometric indices and blood pressure were measured according to standard protocol. Hypertension was defined based on Joint National Committee VI (JNC VI). Biochemical analysis was conducted on fasting blood samples. Diabetes was defined as fasting plasma glucose (FPG) > or =126 mg/dl or 2-h plasma glucose (2hPG) > or =200 mg/dl. Lipid disorders and components of metabolic syndrome were considered based on Adult Treatment Panel III (ATP III). RESULTS: Mean age of women was 39.9+/-14.6 years. Mean body mass index, waist-to-hip ratio, waist and hip circumferences for subjects were 27.1+/-5.1 kg/m2, 0.83+/-0.08, 86.5+/-13.1 cm and 103.5+/-9.8 cm, respectively. Higher hip circumference was associated with lower levels of serum total- and LDL-cholesterol, serum triglyceride, fasting plasma glucose, 2-h plasma glucose, systolic and diastolic blood pressure. Subjects in the top quintile of hip circumference had higher values of serum HDL-cholesterol concentration compared to those in the lower category. After adjustment for potential confounding variables and anthropometric measures associated with higher hip circumference, a significant decreasing trend was observed for odds of having high LDL-cholesterol (odds ratios among quintiles: 1.00, 0.98, 0.97, 0.95, 0.84, respectively, P for trend=0.04), diabetes (1.00, 0.68, 0.58, 0.45, 0.42, P for trend=0.01), hypertension (1.00, 0.96, 0.82, 0.78, 0.70, P for trend 0.02), low serum HDL-cholesterol (1.00, 1.03, 0.86, 0.82, 0.56, P for trend=0.04), elevated blood pressure (1.00, 0.99, 0.82, 0.70, 0.61, P for trend=0.01) and abnormal glucose homeostasis (1.00, 0.69, 0.66, 0.54, 0.48, P for trend=0.01) among hip circumference quintile categories. Individuals in the upper category of hip circumference had lower odds of having hypercholestrolemia (0.86 vs. 1.00) and high serum triglyceride levels (0.74 vs. 1.00) compared to those in the lowest category. CONCLUSION: Hip circumference is independently and inversely associated with metabolic risk factors. This study underscores the importance of continuing to measure hip circumference in epidemiologic surveys in Tehranian adult women.  相似文献   
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