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The purpose of the present investigation was to evaluate the hydrolysis of adenine nucleotides on synaptosomes and platelets obtained from rats exposed to cadmium (Cd) and treated with N-acetylcysteine (NAC). Rats received Cd (2 mg/kg) and NAC (150 mg/kg) by gavage every other day for 30 days. Animals were divided into four groups (n = 4–6): control/saline, NAC, Cd, and Cd/NAC. The results of this study demonstrated that NTPDase and 5′-nucleotidase activities were increased in the cerebral cortex synaptosomes of Cd-poisoned rats, and NAC co-treatment reversed these activities to the control levels. In relation to hippocampus synaptosomes, no differences on the NTPDase and 5′-nucleotidase activities of Cd-poisoned rats were observed and only the 5′-nucleotidase activity was increased by the administration of NAC per se. In platelets, Cd-intoxicated rats showed a decreased NTPDase activity and no difference in the 5′-nucleotidase activity; NAC co-treatment was inefficient in counteracting this undesirable effect. Our findings reveal that adenine nucleotide hydrolysis in synaptosomes and platelets of rats were altered after Cd exposure leading to a compensatory response in the central nervous system and acting as a modulator of the platelet activity. NAC was able to modulate the purinergic system which is interesting since the regulation of these enzymes could have potential therapeutic importance. Thus, our results reinforce the importance of the study of the ecto-nucleotidases pathway in poisoning conditions and highlight the possibility of using antioxidants such as NAC as adjuvant against toxicological conditions.  相似文献   
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Purpose

To compare the learning curves for mastering OP and LP surgical techniques, in terms of effects on completion times and postoperative outcomes/complications.

Methods

A retrospective analysis was performed for 198 patients with hypertrophic pyloric stenosis. The learning curves were in regard to two groups of surgeons: three of whom performed 106 OPs while three others performed 92 LPs. Treatment-related complications were divided into two categories: specific complications relating to the pyloromyotomy and non-specific complications. A logistic regression model with repeated data was used to explore the occurrence of complications.

Results

The overall postoperative complication rates were not significantly different between the OP (15.1 %) and the LP (11.8 %) groups. Specific complications were more frequent in the LP group (6.4 versus 2.8 %), while non-specific complications were more frequent in the OP group (12.1 versus 5.3 %). The occurrence of complications exhibited a statistically decreasing risk with each supplementary procedure that was performed (p = 0.0067) in the LP group, but not in the OP group (p = 0.9665).

Conclusion

From a learning process perspective, laparoscopy is mainly associated with a significantly higher risk of specific complications. This risk decreases in line with the surgeon’s level of experience, whereas non-specific complications remain stable in open procedures.
  相似文献   
106.

Background

Type 1 diabetes patients, although typically lean, experience an increased prevalence of obesity, and bariatric surgery is considered in severe cases. Bariatric surgery in such patients leads to significant weight loss and decreased insulin requirements; however, effects on glycemic control remain discussed. We assessed, in obese patients with type 1 diabetes, the effects of bariatric surgery upon body weight, body composition, and glycemic control, including the occurrence of hypoglycemic events.

Methods

Thirteen obese patients with type 1 diabetes who underwent bariatric surgery (Roux-en-Y gastric bypass n?=?6, sleeve gastrectomy n?=?7) were matched with obese patients without diabetes and with type 2 diabetes patients during 12 months of follow-up. Outcomes included body weight, DXA-assessed body composition, HbA1c, and incidence of hypoglycemia.

Results

At 12 months, median surgery-induced weight loss was 27.9 % (21.1–33.3), 26.1 % (24.8–29.7), and 27.5 % (21.8–32.1) in patients with type 1 diabetes, type 2 diabetes, and without diabetes, respectively, with no significant differences across the groups. Similar findings were observed for body fat changes. At 12 months, median HbA1c decreased from 8.3 to 7.6 % in type 1 diabetes patients versus 8.0 to 5.9 % in type 2 diabetes patients (P?=?0.04 between the groups). In type 1 diabetes patients, the number of reported minor hypoglycemia increased transiently only at 6 months. Two patients reported severe hypoglycemia (one episode each).

Conclusions

Type 1 diabetes patients benefit from bariatric surgery in terms of weight loss and glycemic control. Close monitoring of insulin therapy appears warranted to prevent minor hypoglycemia in the first months post-surgery.
  相似文献   
107.
Tan LP  Ng BK  Balraj P  Lim PK  Peh SC 《Pathology》2007,39(2):228-234
BACKGROUND AND AIMS: Colorectal cancers of different subtypes involve different pathogenic pathways like the Wnt and the mutator pathways. In this study, we screened 73 colorectal cancer cases from a multi-racial group for genetic and expression profile defects with the aim of correlating these with patients' clinicopathological characteristics. METHODS: Mutation screening of the entire coding region of APC and exon 3 of CTNNB1, loss of heterozygosity (LOH) of APC, and microsatellite instability (MSI) status were assessed for 44 patients with available paired frozen normal and tumour tissues. In addition, 29 cases with available paraffin embedded tumour blocks were screened for mutation in exon 3 of CTNNB1, the APC mutation cluster region (codon 1286-1513), and hMLH1, hMSH2, hMSH6 protein expressions by immunohistochemistry method. RESULTS: In our study, 15/73 cases showed APC mutations (20.5%), 1/73 cases had CTNNB1 mutation (1.4%), 5/32 cases had APC LOH (15.6%), and 16/70 (22.9%) cases revealed at least some form of mismatch repair (MMR) defect. Tumour grade (poor differentiation) was found to correlate significantly with right-sided tumour and mucinous histology (p = 0.01879 and 0.00320, respectively). Patients of younger age (below 45 years) more often had tumours of mucinous histology (p = 0.00014), while patients of older age (above 75 years) more often had tumours on the right side of the colon (p = 0.02448). Tumours of the mucinous histology subtype often had MMR defects (p = 0.02686). There was no difference in the occurrence of APC and CTNNB1 mutations and MMR defects found within our multi-racial colorectal cancer patient cohort. CONCLUSION: Our findings support the notion that racial factor may not be related to the occurrence of MMR defects and APC and CTNNB1 mutations in our multi-racial patient cohort.  相似文献   
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AIMS: To examine differences in temporal summation of mechanically evoked pain between women and men suffering from chronic pain associated with temporomandibular disorders (TMD), as well as between male TMD patients and healthy controls. METHODS: Series of 10 repetitive, mildly noxious mechanical stimuli were applied to the fingers of 27 female TMD patients, 16 male TMD patients, and 20 healthy men. The subjects rated the pain intensity caused by the 1st, 5th, and 10th stimulus in the series. Pain ratings were analyzed by 3-way repeated-measures analysis of variance. RESULTS: Pain ratings increased significantly with stimulus repetition for the female TMD patients (P < .001). Women with TMD exhibited significantly greater temporal summation of pain than TMD men (P < .001). Neither the healthy men nor the male TMD patients exhibited significant increases in pain perception with repetitive stimulation. In the female TMD patient group, perceptual pain magnitudes were higher with an interstimulus interval of 2 seconds rather than 10 seconds (P < .005). CONCLUSION: These findings suggest that central nociceptive processing upregulation is likely to contribute to TMD pain for women but is not a factor for  相似文献   
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