Can adiponectin have an additional effect on the regulation of food intake by inducing gastric motor changes?

The regulation of food intake is a complex mechanism, and the hypothalamus is the main central structure implicated. In particular, the arcuate nucleus appears to be the most critical area in the integration of multiple peripheral signals.Among these signals, those originating from the white adipose tissue and the gastrointestinal tract are known to be involved in the regulation of food intake.The present paper focuses on adiponectin, an adipokine secreted by white adipose tissue, which is reported to have a role in the control of feeding by acting centrally. The recent observation that adiponectin is also able to influence gastric motility raises the question of whether this action represents an additional peripheral mechanism that concurs with the central effects of the hormone on food intake. This possibility, which represents an emerging aspect correlating the central and peripheral effects of adiponectin in the hunger-satiety cycle, is discussed in the present paper.     

Plasma levels of neuropeptides in Alzheimer's disease.

BACKGROUND: In the central nervous system, several neuropeptides are believed to be involved in the pathophysiology of Alzheimer's disease (AD). Indeed, previous studies have documented that glucagon-like peptide 1 (GLP-1) possesses neurotropic properties and can reduce amyloid-beta peptide levels in the brain in vivo. Moreover, the concentrations of neuropeptide Y (NPY) seem to be altered in the cerebrospinal fluid of patients with AD and in subjects with major depression. Finally, among the modifications induced by aging, a dysregulation of the ghrelin-growth hormone (GH) system has been reported. METHODS: We investigated the plasma concentrations of these neuropeptides in 14 subjects with AD. Data obtained from these patients were compared with data from an age- and weight-matched healthy group. RESULTS: No significant differences were found between the two groups in relation to plasma levels of GLP-1, NPY, ghrelin and GH. Peripheral NPY concentrations were positively correlated with ghrelin levels in both groups, and with plasma GLP-1 concentration only in controls. CONCLUSION: On the basis of our results, peripheral levels of these neuropeptides seem not to serve as biochemical markers of AD.     

Post-biopsy arteriovenous fistulas of the native kidneys diagnosed by Doppler US

Two patients with arteriovenous fistulas of the native kidney occurring after needle biopsy were evaluated using duplex and color Doppler ultrasonography. The first patient had a fistula with associated pseudoaneurysm: color Doppler showed the lesion as a small rounded area with whirling flow; spectral analysis allowed recognition of both the afferent artery with low impedance flow and the draining vein with pulsatile, arterialized flow. The second patient had a normal color Doppler study; however, spectral analysis demonstrated signals with low vascular impedance from an intra-parenchymal artery at the lower pole, and a jet of turbulent flow. Following disappearance of clinical findings, such Doppler abnormalities were no longer detectable. When a iatrogenic arteriovenous fistula is considered on clinical grounds, both color and Doppler spectral analysis of waveforms from intra-parenchymal vessels should be performed. Possibly, further advances in color Doppler technology will permit the use of this examination as the first imaging procedure in these clinical situations.Correspondence to: L. E. Derchi     

奥利司他对肥胖青少年体重和机体组分的影响——随机对照试验

背景：儿童和青少年超重和肥胖正迅速增加。在该人群，单纯行为疗法减肥及维持体重下降的效果有限，但是对药物治疗尚未进行广泛的研究。 目的：确定奥利州他（Orlistat）在青少年体重治疗方面的效果及其安个性。 设计、地点和病例：于美国和加拿大32个中心、539例肥胖青少年（12—16岁；体重指数[body mass index，BMI]在第95百分化之上≥2单位）进行的多ln0、54剧（2000年8月至2002年10月）随机双盲研究。 干预：给予奥利司他（n=357）或安慰剂（n=182）120mg，每口3次，持续1年；加适度低热卡饮食（脂肪占30％）、运动和行为治疗。 主要观察指标：BMI变化；二级指标包括腰围和髋用、体重下降、脂质测量以及机体对口服葡萄糖的血糖和胰岛素反心。 结果：至12周时，两组BMI均有下降；此后，奥利司他组体重维持稳定而安慰剂组则超过基线。研究结束时，奥利司他组BMI下降0．55。而安慰剂组则增加0．31（P=0．001）。与安慰剂组的15．7％相比，奥利司他组26．5％的病例BMI下降≥5％（P=0．005）；BMI下降≥10％者分别为4．5％和13．3％（P=0．002）。在研究结束时，奥利司他组体重增加0．53kg，安慰剂组增加3．14kg（P〈0．001）。双能X线吸收测量娃示，这种差异可用脂肪体再的变化解释。奥利司他组腰围下降，安慰剂组腰围上升（-1．33cm比＋0．12cm；P〈0．05）。奥利司他组发生轻至中度胃肠道不良事件者为9％-50％，安慰剂组为1％～13％。 结论：与安慰剂比较，奥利司他与饮食、运动和行为改善联合可显著改善肥胖青少年体重的治疗。在这个青少年人群，连续使用奥利司他1年并无重要安全问题，尽管奥利司他组胃肠道不良事件较为常见。     

Diffusion-weighted imaging study of patients with essential tremor.

The pathophysiology of essential tremor (ET) is unknown. PET and fMRI studies have revealed bilateral activation and (1)H-MRS studies metabolic abnormalities in the cerebellum and other functionally related brain structures in ET. Diffusion-weighted imaging (DWI) was used to search for evidence of tissue integrity abnormalities in these areas in ET patients and 10 matched controls by calculating water apparent diffusion coefficients (ADCs). Regions of interest included the left and right cerebellum, red nucleus, thalamus, caudate, putamen, pallidum, and frontal white matter. Histograms of ADCs were generated for all pixels in the infratentorial compartment and manually segmented areas corresponding to brainstem, vermis, and cerebellar hemispheres. ADC values were similar in all brain areas in patients and controls. Our study did not detect changes affecting the investigated brain regions in ET patients. These findings argue against major structural damage in the ET brain, although more subtle neurodegenerative changes cannot be ruled out.