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41.

Introduction

In Tunisia, asymptomatic carriage of Leishmania is poorly documented.

Objective

The aim of the present study was to estimate the frequency of asymptomatic infection among the family members of patients with patent visceral leishmaniasis by using the Western blotting kit based on 14 and 16 kDa bands.

Material and methods

We tested 94 sera collected from 24 patients with patent visceral leishmaniasis and 70 from their families’ members.

Results

The rate of seropositivity was 100% in the group of patients and 54.3% in the group of families’ members. The analysis of the Western blotting patterns showed that the 33 kDa, 24 kDa and to a lesser extent the 22 kDa band were very indicative of patent visceral leishmaniasis in contrast to asymptomatic infection where these bands were very rarely detected.

Conclusion

The results reported herein showed the high frequency of asymptomatic carriers of Leishmania among the families’ members of visceral leishmaniasis cases and the usefulness of the Western blotting as a screening technique and in distinguishing between patent visceral leishmaniasis and the asymptomatic carriage of Leishmania.  相似文献   
42.
Objective and design: We previously described the visceral antinociceptive property of α, β-amyrin in a mouse model of cystitis induced by cyclophosphamide (CPM). This study examined the contribution of vanilloid-1 (TRPV1), peripheral NK1 receptors to CPM-evoked nociceptive behaviors and bladder edema, and its possible modulation by α, β-amyrin. Methods: The effect of α, β-amyrin (10, 30, and 100 mg/kg, p. o.) and N-acetylcysteine (NAC) on CPM (400 mg/kg, i. p.)-induced cystitis was studied in mice. Sensory deafferentation was done by a high dose capsaicin. The parameters analysed were: CPM-evoked noxious behaviors, bladder edema, vascular permeability, and NK1 immunoreactivity. To assess the role of K+ ATP channels in α, β-amyrin effect, animals were pretreated with glibenclamide. Results: α, β-amyrin (30 and 100 mg/kg) and NAC significantly (p < 0.01) suppressed the visceral pain-related behaviors and NK1 immunoreactivity, but bladder edema was reduced weakly. Glibenclamide reversed the effects of α, β-amyrin. Sensory deafferentation by capsaicin significantly reduced the nociceptive responses and the NK1 immunoreactivity to noxious stimulation by CPM. Conclusions: α, β-amyrin attenuates CPM-induced visceral pain and bladder edema by mechanisms that involve, at least in part, a block either of Substance P release or its receptor function, and partly by opening K+ ATP channels. Received 13 February 2007; returned for revision 13 April 2007; accepted by G. Geisslinger 14 May 2007  相似文献   
43.
Complex vascular anatomy often affects endovascular procedural outcome. Accurate quantitative assessment of three-dimensional (3D) in-vivo arterial morphology is therefore vital for endovascular device design, and preoperative planning of percutaneous interventions. The aim of this work was to establish geometric parameters describing arterial branch origin, trajectory, and vessel curvature in 3D space that eliminate the errors implicit in planar measurements. 3D branching parameters at visceral and aortic bifurcation sites, as well as arterial tortuosity were determined from vessel centerlines derived from magnetic resonance angiography data for three subjects. Errors in coronal measurements of 3D branching angles for the right and left renal arteries were 3.1 ± 3.4° and 7.5 ± 3.7°, respectively. Distortion of the anterior visceral branching angles from sagittal measurements was less pronounced. Asymmetry in branching and planarity of the common iliac arteries was observed at aortic bifurcations. The renal arteries possessed considerably greater 3D curvature than the abdominal aorta and common iliac vessels with mean average values of 0.114 ± 0.015 and 0.070 ± 0.019 mm−1 for the left and right, respectively. In conclusion, planar projections misrepresented branch trajectory, vessel length, and tortuosity proving the importance of 3D geometric characterization for possible applications in planning of endovascular interventional procedures and providing parameters for endovascular device design.  相似文献   
44.
Abdominal fat accumulation is known to be strongly implicated in development of metabolic syndrome (MetS). We examined diagnostic values of obesity-related parameters in 95 men and 185 women, and we determined optimal cutoff values of visceral fat area (VFA) and waist circumference (WC) for predicting the presence of multiple non-adipose components of MetS. Receiver operating characteristic (ROC) curve analysis revealed that VFA was the best indicator of MetS. WC and VFA exhibited similar diagnostic values for men and postmenopausal women, whereas WC was inferior to VFA for premenopausal women (area under ROC curve of VFA and WC was 0.76 and 0.52, respectively; P < 0.001). Optimal cutoff points of VFA and WC for predicting MetS were 136 cm(2) and 89 cm in men and 95 cm(2) and 82 cm in women, respectively. Subjects with VFA and WC above these cutoff values exhibited increased insulin resistance and increased carotid intima-media thickness. In conclusion, WC has a diagnostic value similar to VFA for predicting MetS in men and postmenopausal women, but not in premenopausal women. Further studies are necessary to develop a simple clinical parameter that reflects visceral fat in premenopausal women.  相似文献   
45.
Stress may induce eating in the absence of hunger, possibly involving changes in food reward, i.e. ‘liking’ and ‘wanting’. The objective of this study was to assess the effects of acute psychological stress on food reward, and on energy intake, in visceral overweight (VO) vs. normal weight (NW) subjects. Subjects (27 NW, age = 26 ± 9 yrs, BMI = 22 ± 2 kg/m2; 15 VO, age = 36 ± 12 yrs, BMI = 28 ± 1 kg/m2) came to the university twice, fasted, for either a rest or stress condition (randomized cross-over design). Per test-session ‘liking’ and ‘wanting’ for 72 items divided in six categories (bread, filling, drinks, dessert, snacks, and stationery (control)) were measured twice, each time followed by a wanted meal. Appetite profile (visual analogue scales, VAS), heart rate, mood state and level of anxiety (POMS/STAI questionnaires) were measured.High hunger and low satiety (64 ± 19, 22 ± 20 mmVAS) confirmed the fasted state. Elevated heart rate, anger and confusion scores (p ≤ 0.03) confirmed the stress vs. rest condition. Consumption of the first meal decreased hunger, increased satiety, and decreased ranking of ‘liking’ of bread vs. increased ranking of ‘liking’ of the control (p < 0.001). ‘Wanting’ for dessert and snacks, energy intake, carbohydrate and fat intake for the second meal stress vs. rest relatively increased in VO vs. decreased in NW (p < 0.02). During stress vs. rest VO showed a 6 ± 9% increase in percentage of daily energy requirements consumed over the two meals (p = 0.01).To conclude, visceral overweight subjects showed stress-induced food intake in the absence of hunger, resulting in an increased energy intake.  相似文献   
46.
目的 探查间质核 (INV)内内脏传入终末与向臂旁核 (PBN)投射的NOS阳性神经元之间的联系。 方法 逆行、跨神经节追踪以及免疫荧光组织化学方法 ,结合激光共聚焦扫描显微镜观察。 结果 PBN内注射四甲基罗丹明 (TMR)后 ,逆行标记细胞主要位于注射侧的INV ,大多属 2 0 μm以下的中、小型细胞。NOS阳性细胞与TMR逆行标记细胞分布区域重叠。NOS TMR双标记细胞分别占NOS阳性细胞总数的 5 4 8% (17 31)和TMR逆行标记细胞总数的 34% (17 4 9)。舌咽和迷走神经内注射生物素化葡聚糖胺 (BDA)跨神经节标记的内脏神经初级传入终末点状膨体贴近双标记细胞胞体 ,呈紧密接触状。 结论 可能存在经INV向PBN投射的内脏伤害性信息传导通路 ,作为神经递质和神经信息分子的NO可能参与其内脏伤害性信息的传递和调控  相似文献   
47.
48.
目的 探讨纳西族各项肥胖指标与体脂率的关系。 方法 选取云南省丽江市玉龙县687名18~90岁成年纳西族人,运用人体测量法和生物电阻抗法测量其体重、身高、胸围、腰围、臀围、肱二头肌皮褶、肱三头肌皮褶、肩胛下皮褶、髂嵴上皮褶、髂前上棘皮褶、体质量指数(BMI)、内脏脂肪等级和体脂率等指标,并将各项指标分别与体脂率进行统计分析。 结果 纳西族成人的平均体脂率男性为正常水平,女性属于肥胖。按照内脏脂肪等级为标准,纳西族男性和女性均在正常范围内。根据腰围的判断标准,纳西族男性腰围在正常范围内,而女性腰围属于腹型肥胖。相关分析表明,纳西族成人的体重、胸围、腰围、臀围、肱二头肌皮褶、肱三头肌皮褶、肩胛下皮褶、髂嵴上皮褶、髂前上棘皮褶、BMI、内脏脂肪等级与体脂率均成正相关。纳西族男性内脏脂肪等级与体脂率相关性最强,其次是BMI;纳西族女性胸围与体脂率相关性最强,其次是腰围。 结论 纳西族成人各项肥胖指标均与体脂率成正相关,相关程度存在性别、地区和民族差异。  相似文献   
49.
目的 探讨大鼠三叉神经脊束间质核(INV)内接受内脏伤害性信息的含calbindin D-28K(CB)神经元与孤束核(NTS)的投射联系。方法 用福尔马林刺激上消化道,应用荧光金(FG)逆行束路追踪结合Fos和CB的免疫荧光组织化学三重标记法。结果 INV的背侧边缘旁核(PaMd)和三叉旁核(PaV)内可见到大量FG逆标细胞,以注射FG的同侧为主。大部分FG逆标细胞(约71.2%)为CB免疫反应阳性。部分FG和CB双标记神经元(约31.5%)同时呈Fos免疫反应阳性的三重标记。结论 INV内部分接受内脏伤害性刺激的CB神经元可直接投射至NTS,含CB的神经元在内脏伤害性信息经INV向NTS的传导通路中,可能发挥重要作用.  相似文献   
50.
The effects of K+ depolarization and of the muscarinic agonist carbachol on [Ca2+]i and force were investigated in smooth muscle sheets of the longitudinal layer of the ileum loaded with Fura-2. K+ -rich solutions increased [Ca2+]i and force to an initial peak value, which was determined by the concentration of [K+]o. Thereafter, [Ca2+]i and force declined to a lower maintained level. The Ca2+/force relationship observed during this contraction-relaxation cycle is represented by a clockwise hysteresis loop. At 140 mM [K+]o, this loop consisted of three components while at lower [K+]o a two-component loop was observed. The stimulation with 0.1 mM carbachol resulted in a transient increase of [Ca2+]i and force followed by a continuous decline of these parameters despite the presence of the drug. Its EC50 of relaxation was around 270 nM [Ca2+]i. The Ca2+/force relationship proceeded along a counterclockwise hysteresis loop during the contraction-relaxation cycle. The extent of this loop decreased but remained unaltered in its direction during repeated stimulation with carbachol. These results suggest that (a) both agonists increase force and [Ca2+]i during stimulation; (b) during depolarization with K+, desensitization to Ca2+ occurs resulting in a clockwise hysteresis loop; (c) during carbachol stimulation, a counterclockwise hysteresis is observed. This could be due to an increased sensitivity to Ca2+ mainly in tonic smooth muscle. These observations might be explained by a modulation of the Ca2+ sensitivity by sensitizing and desensitizing mechanisms. These modulations during different stimuli could be due to different myosin light-chain kinase/myosin light-chain phosphatase ratios.  相似文献   
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