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71.
The chemical composition of the chromatography 63 subfraction (63SF) from the ethyl acetate soluble fraction of the crude extract of Croton celtidifolius bark presented a high content of total proanthocyanidins (75.0+/-2.3%). HPLC analysis of 63SF revealed a dimeric profile (e.g.catechin-(4alpha-->8)-catechin and gallocatechin-(4alpha-->8)-catechin) and polymeric proanthocyanidins. In pharmacological investigations, 63SF administered intraperitoneally exhibited dose-dependent antinociceptive activity against several chemical stimuli, including the intraperitoneal injection of acetic acid (ID50 (the dose of 63SF which was able to reduce the nociceptive response by 50% relative to the control value)=0.9 (0.5-1.6)) and the intraplantar injection of capsaicin (ID50=13.0 (10.0-17.0)), glutamate (ID50=4.0 (2.0-7.0)) and formalin (ID50 first phase=36.0 (24.0-53.0) and late phase=11.0 (8.0-14.0)). 63SF administered orally exhibited an antinociceptive effect in the formalin test (ID50 first phase=125.0 (89.0-177.0) and late phase=65.0 (33.0-95.0)). In the same test, 63SF was effective when given soon after the first phase, as well as exhibiting therapeutic activity. Furthermore, 63SF was effective in models of thermal nociception including tail-flick and hot-plate tests. When the mice were treated in the neonatal period with capsaicin, the antinociceptive effect of 63SF in the first phase of the formalin test was abolished, but pretreatment with naltrexone did not change the antinociceptive effect of 63SF. Together, these results provide evidence that 63SF exerted a pronounced systemic antinociception against chemical (acetic acid, formalin, glutamate and capsaicin tests) and thermal (hot-plate and tail-flick tests) nociceptive models of pain in mice at a dose that did not interfere with the locomotor activity. The mechanism by which this sub-fraction produced antinociception remains unclear, but it is unlikely to involve the activation of the opioid system. However, unmyelinated C-fibres sensitive to treatment with capsaicin are likely to participate in antinociception caused by 63SF.  相似文献   
72.
The mechanisms involved in the association between air pollution and increased cardiovascular morbidity are not fully understood. The objective of this study was to test the hypothesis that fine particulate matter (PM(2.5)) induces systemic inflammation and vasoconstriction of small arteries in the lung and heart of rats. Thirty-eight healthy Wistar rats were anesthetized, intubated, and submitted to the instillation of 1 ml of distilled water diluted in the following solution: blank filter, 100 microg and 500 microg of PM(2.5). PM(2.5) was collected in glass fiber filters with a high-volume sampler. The animals were sacrificed 24 h after instillation when blood, heart, and lung samples were collected for morphological and wet-to-dry weight ratio analysis. PM(2.5) consisted of the following elements: sulphur, arsenic, bromine, chlorine, cobalt, iron, lanthanum, manganese, antimony, scandium, and thorium. Total reticulocytes significantly increased at both PM(2.5) doses (p < 0.05) while hematocrit levels increased in the 500 microg group (p < 0.05). Quantification of segmented neutrophils and fibrinogen levels showed a significant decrease, while lymphocytes counting increased with 100 microg of PM(2.5) (p < 0.05). A significant dose-dependent decrease of intra-acinar pulmonary arteriole lumen/wall ratio (L/W) was observed in PM groups (p < 0.001). Peribronchiolar arterioles L/W showed a significant decrease in the 500 microg group (p < 0.001). A significant increase in heart wet-to-dry weight ratio was observed in the 500 microg group (p < 0.001). In conclusion, fine environment particles in the city of S?o Paulo promote pulmonary and cardiac histological alterations. Pulmonary vasculature was markedly affected by particle instillation, resulting in significant vasoconstriction in healthy rats.  相似文献   
73.
Cannabinoid receptor agonists significantly inhibit nociceptive responses in a large number of animal models. The present study examined whether mice displaying different basal levels of anxiety in the plus-maze test of anxiety might differ in terms of responsiveness to the antinociceptive effects of Delta(9)-tetrahydrocannabinol (Delta(9)-THC). Further, the involvement of the cannabinoid and/or opioid receptors in Delta(9)-THC-induced antinociception was investigated by using SR 141716A and naloxone, respectively, cannabinoid and opioid receptor antagonists. Delta(9)-THC-induced antinociception was evaluated in the formalin test that involves a biphasic response with an early and a late phase of high paw-licking activity. This characteristic biphasic response was observed in all control animals selected as "anxious" and "nonanxious." Delta(9)-THC (0.5-5 mg/kg i.p.) caused a dose-dependent antinociceptive effect in both groups of mice during the early and late phases. This response was fully reversed by SR 141716A (1 mg/kg i.p.) and partially reversed by naloxone (2 mg/kg i.p.). These findings suggest that mice selected for differences in anxiety-related behavior show similar responses to the antinociceptive action of Delta(9)-THC and that this action involves predominantly cannabinoid mechanisms.  相似文献   
74.
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76.
This work was designed to evaluate the toxicity of inhalable particles [less than/equal to] 10 microm in aerodynamic diameter (PM(10)) collected from the urban air in São Paulo, Brazil, to the mucociliary apparatus using the frog palate preparation. Seven groups of frog palates were immersed in different concentrations of PM(10) diluted in Ringer''s solution during 120 min: 0 (control, n = 31); 50 (n = 10); 100 (n = 9); 500 (n = 28); 1,000 (n = 10); 5,000 (n = 11); and 10,000 microg/m(3) (n = 10). Mucociliary transport and transepithelial potential difference were determined at 0, 30, 60, and 120 min exposure. Additional groups (control and 500 microg/m(3)) were studied by means of morphometric analyses (quantification of the amount of intraepithelial and surface mucins), measurement of cilia beat frequency, and quantification of total glutathione. Mucociliary transport and transepithelial potential difference were significantly decreased at higher concentrations of PM(10) (p = 0.03 and p = 0.02, respectively). Exposure to PM(10) also elicited a significant decrease of total glutathione (p = 0. 003) and depletion of neutral intraepithelial mucins (p = 0.0461). These results show that PM(10) can promote significant alterations in ciliated epithelium in vitro.  相似文献   
77.

Introduction and hypothesis

The pelvic floor muscles (PFM) play an important part in the urinary continence mechanism. Changes in their structure and functionality may lead to a predisposition to pelvic floor dysfunction such as urinary incontinence (UI), which is the involuntary loss of urine. Some techniques for conservative treatment of UI are already well documented. However, new approaches have been found that require scientific proof of their effectiveness, such as vibratory stimulation (VS). Thus, we performed a systematic review of studies that investigated the use of perineal VS (PVS) for the treatment of stress UI.

Materials and methods

This study followed the recommendations of the Cochrane Collaboration for systematic reviews. Studies that used PVS for the treatment of female UI were eligible.

Results

A total of 56 studies were found, of which ten were duplicates and were excluded. Analysis of the titles and abstracts led to the exclusion of 30 studies, leaving 16 for detailed analysis. Of these, only three were included as they fulfilled all the eligibility criteria previously established for the present study. In spite of the heterogeneity of the protocols, all the studies had the goal of assessing the effects of vibration on the PFM, and the stimulation was found to be effective in reducing urinary leakage, improving muscle strength and consequently the patients’ quality of life.

Conclusions

Because of the heterogeneity and the small number of studies, it is not possible to draw a conclusion as to the effectiveness of PVS for the treatment of stress UI, and further studies are needed to provide scientific support for its use.
  相似文献   
78.
BACKGROUND: Severe traumatic brain injury (TBI) is associated with a 30%-70% mortality rate. S100B has been proposed as a biomarker for indicating outcome after TBI. Nevertheless, controversy has arisen concerning the predictive value of S100B for severe TBI in the context of multitrauma. Therefore, our aim was to determine whether S100B serum levels correlate with primary outcome following isolated severe TBI or multitrauma in males. METHODS: Twenty-three consecutive male patients (age 18-65 years), victims of severe TBI [Glasgow Coma Scale (GCS) 3-8] (10 isolated TBI and 13 multitrauma with TBI) and a control group consisting of eight healthy volunteers were enrolled in this prospective study. Clinical outcome variables of severe TBI comprised: survival, time to intensive care unit (ICU) discharge, and neurological assessment [Glasgow Outcome Scale (GOS) at ICU discharge]. Venous blood samples were taken at admission in the ICU (study entry), 24 h later, and 7 days later. Serum S100B concentration was measured by an immunoluminometric assay. RESULTS: At study entry (mean time 10.9 h after injury), mean S100B concentrations were significantly increased in the patient with TBI (1.448 microg/L) compared with the control group (0.037 microg/L) and patients with fatal outcome had higher mean S100B (2.10 microg/L) concentrations when compared with survivors (0.85 microg/L). In fact, there was a significant correlation between higher initial S100B concentrations and fatal outcome (Spearman's =0.485, p=0.019). However, there was no correlation between higher S100B concentrations and the presence of multitrauma. The specificity of S100B in predicting mortality according to the cut-off of 0.79 microg/L was 73% at study entry. Conclusions: Increased serum S100B levels constitute a valid predictor of unfavourable outcome in severe TBI, regardless of the presence of associated multitrauma.  相似文献   
79.
Four topical drugs were studied with regard to their ability to promote healing of open wounds in 60 Wistar rats. Five study groups were defined. Four of the five groups received one of the following substances: papain, sugar, minoxidil, or glucan. The fifth group or control group received saline solution (NaCl, 0.9%). An experimental model with wound standardization (6 × 3.5 cm) was used. The raw area and new epithelium were quantified in each rat by taking photographs from which planimetry was performed. The closure of the first lesion occurred on the 49th postoperative day. Quantitative assessment of collagen deposition was performed using image analyzing software on slides stained with picrosirius and observed under polarized light. Epithelium formation was greatest in the minoxidil group, followed (in decreasing order) by the sugar, papain, control, and glucan groups. Significant differences in collagen deposition were observed among all the groups. The greatest amount of collagen was quantified in the glucan group, followed (in decreasing order) by the sugar, minoxidil, papain, and control groups. This data and possible mechanisms for the interference of each substance in wound healing are considered.  相似文献   
80.
PURPOSE: Our objective was to establish thyroid volume by sonography in Brazilian schoolchildren and to correlate thyroid volume with anthropometric characteristics. METHODS: Sonographic studies of thyroid volume were conducted in 1,977 schoolchildren (6-14 years old) from 21 villages and towns in Central Brazil. Iodine concentration was analyzed in urine specimens and in salt samples obtained from the children's homes. Thyroid volumes were also compared with volumes reported for other countries. RESULTS: Age, height, and weight correlated with thyroid volume. Thyroid volumes for boys and girls were generally lower than those obtained in Europe and comparable to those obtained in Malaysia and Iran. Urinary iodine excretion was considered elevated in about half of the Brazilian schoolchildren, and the iodine content of salt samples was more than 50 ppm in 58%. CONCLUSIONS: We observed relatively smaller thyroid gland volumes in Brazilian schoolchildren as compared with those reported in Europe. This was apparently due to a higher iodine intake in our population.  相似文献   
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