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101.
PURPOSE: Extracorporeal shockwave lithotripsy (SWL) is one of the most common treatments for urinary stones. Despite technological improvements, it may cause side effects varying from minor reversible microscopic damage to severe large renal hematomas. The aim of our experimental study is to assess the efficacy of inosine in avoidance of acute renal damage after SWL. MATERIALS AND METHODS: We used 25 Wistar rats that had previously had left nephrectomy. The rats were divided into three groups: group A consisted of 10 rats undergoing renal SWL; group B consisted of 10 rats that received adjunctive treatment with IP injection of inosine 40 minutes before SWL; and group C consisted of 5 rats that served as controls. N-acetylglucosaminidase (NAG) and lactate dehydrogenase (LDH) concentrations were evaluated 24 hours before and 24 hours after SWL. All the rats were subsequently sacrificed (4 rats in group A and 4 in group B at 48 hours post-SWL, and the remaining rats were sacrificed 30 days post-SWL). Renal tissue was submitted to histologic and electron microscopic examination to assess early and late alterations. RESULTS: NAG and LDH values were significantly increased after SWL in group A (P<0.001), while no significant NAG and LDH differences were detected in group B (P<0.16). Early histologic examination revealed a considerable amount of cellular degeneration in group A with ultrastructural vacuolization and disruption of lysosomal membranes; the tubular features and cellular structures appeared to be well preserved in group B. No late histologic alterations were evident in any of the specimens. CONCLUSIONS: Inosine is helpful and protective in the prevention of early microscopic damage to renal parenchyma due to SWL.  相似文献   
102.
A number of condensed azines, mostly belonging to the families of indeno-fused pyridazines (1), pyrimidines (2, 3), and 1,2,4-triazines (4, 5), were synthesized and evaluated in vitro as monoamine oxidase (MAO) A and B inhibitors. Most of them showed higher inhibition potency toward MAO-B, the most effective one being 3-(3-nitrophenyl)-9H-indeno[1,2-e] [1,2,4]triazin-9-one (4c), which displayed an IC50 value of 80 nM and proved to be 10-fold more potent than its [2,1-e] fusion isomer 5. Replacing the 3-phenyl group of the known indeno[1,2-c]pyridazin-5-one MAO-B inhibitors with a flexible phenoxymethyl group enhanced the inhibitory potency. The inhibition data highlighted the importance of the aza-heterocyclic scaffold in affecting the MAO isoform selectivity. The 3-phenyl derivatives with type 1, 4, and 5 scaffolds were inhibitors of MAO-B with little or no MAO-A effect, whereas 2- or 3-phenyl derivatives of type 2 and 3 pyrimidine-containing fusion isomers inhibited both isoenzymes with a structure-dependent preference toward MAO-A.  相似文献   
103.
Abstract: Idiopathic facial aseptic granuloma (IFAG), or pyodermite froide du visage, is a skin disease reported only in children and characterized by painless red nodules usually located on the cheeks. Its etiology is still unclear, but some authors considered the possibility that IFAG might be included in the spectrum of granulomatous rosacea (GR). The histopathological features of IFAG and GR are quite similar, showing perifolliculitis, granulomas, folliculitis, and lymphocytes and plasmacells around epithelioid histiocytes. In the present article, we discuss three cases in which an association between a facial nodule, compatible with both IFAG and GR, and recurrent chalazia make us support the hypothesis that IFAG should be considered as GR.  相似文献   
104.
Vitrimers are a class of polymers that combine the chemical and mechanical properties of traditional thermosets with the reshaping and reprocessing features of thermoplastics. Their reshaping ability is given by the presence of reversible bonds within their structure. While the nature of bonds that can ensure a dynamic behavior to the crosslinked network is well established, the challenge remains open to assess and control the reactivity of the system to rationally develop materials with desirable features in terms of processability and recyclability. In this work, a “free-model” analysis of the curing reaction of an epoxy/anhydride resin in presence of zinc acetylacetonate as catalyst for both the curing reaction and transesterification is performed. Isothermal and non-isothermal tests are conducted, and the data obtained are analyzed by means of isoconversional methods. The goal is to get an in-depth insight into the reaction mechanism and the structure deriving from the crosslinked network formation, which can ultimately determine the material properties and eventually its actual reprocessability.  相似文献   
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Type 1 diabetes mellitus (T1DM) and other chronic diseases in children are well known to adversely affect linear growth and pubertal development. In the years immediately following the introduction of insulin therapy, short stature was consistently reported in children with T1DM. However, over the past 50 years significant improvement in the prognosis for growth and final height in children with diabetes has been achieved. Although pre-pubertal and post-pubertal growth are important phases in growth, puberty and its related hormonal changes represent a critical phase for growth gain and final height particularly in patients with T1DM. Growth impairment reported in diabetic patients is dependent on abnormalities in physiological bone growth and corresponds to abnormalities of the growth hormone-insulin-like growth-I (GH-IGF-I) axis. These alterations seem to be related to appropriate insulin levels and thereby to glycaemic control as judged by haemoglobin levels. Modern diabetes care, particularly intensified insulin regimens, might improve metabolic control in patients with T1DM, therefore preventing abnormalities of the GH-IGF-I axis and leading to normal growth and final height similar to that of their unaffected peers.  相似文献   
108.
AIM: To investigate the serum erythropoietin (Epo) levels in patients with chronic liver diseases and to compare to subjects with iron-deficiency anaemia and healthy controls. METHODS: We examined 31 anaemic (ALC) and 22 non-anaemic (NALC) cirrhotic patients, 21 non- anaemic subjects with chronic active hepatitis (CAH), 24 patients with iron-deficiency anaemia (ID) and 15 healthy controls. Circulating Epo levels (ELISA; R and D Systems, Europe Ltd, Abingdon, UK) and haemoglobin (Hb) concentration were determined in all subjects. RESULTS: Mean+/-SD of Epo values was 26.9+/-10.8 mU/mL in ALC patients, 12.5+/-8.0 mU/mL in NALC subjects, 11.6+/-6.3 mU/mL in CAH patients, 56.4+/-12.7 mU/mL in the cases of ID and 9.3+/-2.6 mU/mL in controls. No significant difference (P>0.05) was found in Epo levels between controls, CAH and NALC patients. ALC individuals had higher Epo levels (P<0.01) than these groups whereas ID subjects had even higher levels (P<0.001) than patients suffering from ALC. CONCLUSION: Increased Epo values in cirrhotics, are only detectable when haemoglobin was lesser than 12 g/dL. Nevertheless, this rise in value is lower than that observed in anaemic patients with iron-deficiency and appears blunted and inadequate in comparison to the degree of anaemia.  相似文献   
109.
110.

Objectives

Systemic sclerosis (SSc) causes functional and structural microcirculatory dysfunction, affecting also distal extremities. Optical Near-InfraRed Spectroscopy (NIRS) of blood HbO2 saturation (stO2) is able to evaluate O2 delivery/consumption balance in the explored tissue. The NIRS-sensitive camera non-invasively detects stO2 values in superficial tissues, automatically generating 2D-imaging maps in real time. We aimed at testing whether NIRS hand imaging may evaluate peripheral microcirculatory dysfunction and its spatial heterogeneity in SSc patients compared to controls.

Methods

Forty SSc patients (aged 55.1?±?15.6 years) and twenty-one healthy controls (aged 54.3?±?14.5years, p?=?0.89) were studied by palmar hand NIRS-2D imaging. A blood pressure cuff was applied to the forearm and 3 min ischemia was induced. Images were acquired at basal conditions and every 10 seconds during 3 minutes of ischemia and 5 minutes of reperfusion. Five regions of interest were positioned on each fingertip, from the second to the fifth finger and one on the thenar eminence.

Results

A significant difference was found between controls and SSc patients in basal stO2 (84.3?±?7.5?vs. 75.4?±?10.9%, p?<?0.001), minimum stO2 (65.2?±?8.0?vs. 53.4?±?10.1%, p?<?0.001) and time to maximum stO2 during hyperemia (63?±?38?vs. 85?±?49?s, p?<?0.05). Among clinical characteristics, anti-Scl70 antibody positivity, digital ulcers history and smoke exposure affected NIRS parameters, as well as sildenafil and statins therapy. Conversely, no significant differences were found in NIRS-2D values between different nailfold-videocapillaroscopy patterns.

Conclusion

NIRS-2D imaging is a simple, automated tool to non-invasively detect regional microcirculatory impairment in SSc, which seems to add significant functional information to the morphological picture of nailfold-videocapillaroscopy.  相似文献   
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