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991.
The effect of treatment on relapses of Trypanosoma brucei (T. b.) brucei infections in mice in relation to passage of the parasites across the blood-brain barrier (BBB) as visualized by immunohistochemistry was studied. Three daily intraperitoneal injections of 20mg/kg suramin starting at 15 days post-infection (p.i.), when trypanosomes had begun to traverse the BBB, were curative, but not when starting at 21 days p.i. when parasite brain invasion was more pronounced. Relapses occurred in all mice after one or two daily injections of suramin starting at 15 days p.i., but they were delayed when treatment was supplemented with minocycline, which impedes penetration of T. b. brucei into the brain. This study supports the notion that suramin may be effective even when minor parasite neuroinvasion has appeared in African trypanosomiasis and it shows that minocyline can affect relapses of the disease.  相似文献   
992.
To assess the efficacy of ileal transposition with sleeve gastrectomy (SGIT) surgery in remission of Type 2 Diabetes Mellitus (T2DM) in patients with 23–35 BMI. Diabetes is considered a life style disease. Despite medications and lifestyle changes, (HbA1c) - remains > 7 in 56 % of diabetics, predisposing them to high risk of diabetes related complications. Bariatric surgery results in remission of diabetes in over 84% patients with BMI?>?35 m2s/m2. Based on hindgut hypothesis suggesting role of incretins like GLP-1, early trials of ileal interposition surgery have displayed consistent HbA1c levels below 7 in over 80% patients with BMI?>?30 m2/m2. In developing countries majority of T2DM patients are not morbidly obese and surgical procedures are to be evaluated for their efficacy in this group. In this study we have assessed the efficacy of ileal transposition with sleeve gastrectomy (SGIT) in 23–35 BMI T2DM patients. Selected T2DM patients [HbA1c?>?7, C Peptide?>?-1 ng/ml] underwent Lap SGIT by a single surgeon. Data of first five patients with minimum 6 months follow up was analyzed for glycemic control and altered need for medications. Data were analyzed using SPSS (SPSS release 16; SPSS Inc. Chicago). The study target (HbA1c?<?7) was achieved in 60% of patients within 1 month and in 100% of patients within 6 months. Requirement of medications reduced significantly within 6 months and their HbA1c levels reduced from 9.65% to 6.22%. Laparoscopic SGIT may represent a new paradigm for the treatment of T2DM even in non morbidly obese patients.  相似文献   
993.
Acinar cell carcinoma (ACC) of the pancreas is a rare tumor with an extremely low incidence rate. While the number of reported patients with ACC is relatively small, a long-term survival rate has been noted in patients with neuroendocrine differentiation. A 39-year-old woman visited our emergency department for upper gastrointestinal bleeding. Endoscopy indicated extrinsic compression of the posterior body of the stomach, together with a large, 10-cm, central ulcer covered with necrotic tissue. Abdominal computed tomography (CT) indicated a lesion that involved the whole of the pancreas, with a fistula in the stomach, which was suspected of being a degenerative intraductal papillary mucinous tumor of the pancreas. Magnetic resonance imaging (MRI) of the pancreas was performed, and the results further strengthened our suspicions by demonstrating the presence of cystic lesions and tumor buds. A total duodenopancreatectomy, including total splenectomy and gastrectomy, was performed, along with two independent Roux-en-Y anastomoses (one esojejunal and one hepaticojejunal). The tumor also had a wide opening in the stomach. The patient's postoperative course was marked by partial thrombosis of the portal vein, which was treated medically. Histopathological examination provided evidence of pancreatic ACC. The diagnosis of ACC should be considered in the presence of cutaneous lesions, which were absent in the case of our patient, and colonoscopy is also highly desirable because of the various forms associated with familial adenomatous polyposis. The prognosis, which includes a 5-year survival rate of 45%, in the population with an R0 resection is better than that for ductular adenocarcinoma, thus prompting the more aggressive management of this type of tumor.  相似文献   
994.
Beh?et's disease (BD) is an idiopathic multisystem disorder. Involvement of CNS occurs in 4-48% of cases. This study was designed to evaluate the prevalence of subclinical neuropsychiatric affection in asymptomatic Egyptian BD patients using psychometric tests and brain imaging with single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI), also to assess possibly associated clinical predictive variables. Twenty-five BD patients without overt CNS involvement and ten healthy controls matched for age, education, and sex completed a comprehensive neuropsychological battery including Hamilton scales for anxiety and depression and Wechsler memory scale-revised. Disease activity was assessed using Beh?et's Disease Current Activity Form (BDCAF). SPECT was done for all subjects, and 12 patients underwent brain MRI. Compared to controls, 23 (92%) and 24 (96%) patients had anxiety and depression scores respectively above normal range; also, BD patients had significantly lower memory quotient (MQ). SPECT revealed abnormalities in 16/25 (64%), while in 3/12 patients (25%), MRI was abnormal. Subjects with abnormal SPECT had significantly higher ages than those with normal SPECT (P?=?0.02) and were more frequently males (P?=?0.03). No statistically significant differences between cases with normal or abnormal SPECT were found regarding disease duration, frequency of headache, BDCAF, frequency of active eye disease, major vascular involvement, mean Hamilton anxiety and depression scores, and mean MQ. Early diagnosis of neurological involvement in BD is important in reducing or preventing complications. Neuropsychiatric evaluation and HMPAO brain SPECT were found to be useful for detecting subclinical neurological abnormalities in BD patients.  相似文献   
995.
Skeletal relapse is a major concern after correction of retrognathism with surgical mandibular advancement. It was hypothesized that the stimulation from a direct electric current can accelerate the osseous repair through the enhancement of the maturation of fibrocartilage. Furthermore, this stimulation may enhance the mechanical properties of the facial osteotomy site and reduce the skeletal relapse. The purpose of the present study was to examine the osteotomy site histologically and determine the effect of post‐surgical electrical stimulation on the healing of a facial osteotomy site in a rat model. Three groups of adult male Sprague–Dawley rats, 15 in each group (direct electric current, electric sham, and control), were used to generate data. Electrodes were placed in both the direct electric current and the electric sham groups. A 20‐μA direct current was delivered to the osteotomy site only in the direct electric current group.
Histological slides of the osteotomy site for each animal were prepared and interpreted to characterize the healing process of the osteotomy site for each animal. The results showed no statistically significant difference among the three groups of animals (p>0.005). An examination with histology earlier in the healing process and the utilization of an experimental animal with a larger jaw are suggested for any further investigation that involves electrical stimulation and osseous healing in a facial osteotomy site.  相似文献   
996.
Background: The intragastric (IG) ethanol infusion model results in fatty liver, necrosis, inflammation and fibrosis. This model was utilized to study the pathogenesis of alcoholic liver disease (ALD). Disadvantages of the IG model include maintenance of the animals and equipment expense. To develop a voluntary feeding model for ALD, we took advantage of two important observations in the IG model: (i) female rats demonstrate greater severity of alcohol‐induced liver injury than males and (ii) rats fed fish oil as a source of fatty acids develop more severe alcoholic liver injury than rats fed other fatty acids with ethanol. Methods: Female Wistar rats (205 to 220 g) were fed for 8 weeks a diet containing 8% ethanol, fish oil (30% of calories), protein, and dextrose. Pair‐fed controls (FD) received dextrose in amounts isocaloric to ethanol. The following measurements were made: liver pathology [fatty liver (0 to 4), necrosis, inflammation and fibrosis by Sirius Red], endotoxin and alanine aminotransferase (ALT) in plasma, urine ethanol, lipid peroxidation, nuclear factor kappa‐B (NF‐κB) and mRNA levels for tumor necrosis factor‐alpha (TNF‐α), cyclooxygenase‐2 (COX‐2), and inducible nitric oxide synthase (iNOS). Protein levels for iNOS and nitrotyrosine were evaluated by immunohistochemistry and Western Blot analysis. Liver proteasome and cytochrome P450 2E1 activity and protein levels of asialoglycoprotein receptor (ASGPR) were also evaluated. In addition, mRNA levels of fibrogenic markers were assessed. Results: All animals lost weight for the initial 2 to 3 weeks but then gained weight until killing at 8 weeks. There was, however, a significant difference (p < 0.05) in weight between the ethanol‐fed (Etoh) and (FD) groups at the end of the experiment. The mean urine ethanol levels ranged between 190 and 240 mg/dl. The severity of pathological changes was greater (p < 0.01) in Etoh vs. FD: fatty liver, 3.0 ± 1.2 vs. 1.2 ± 0.4; necrosis (foci/mm2), 3.9 ± 2.3 vs. 0.4 ± 0.3; inflammation (cells/mm2), 19.0 ± 6.3 vs. 1.8 ± 0.6. Centrilobular collagen deposition (% area), assessed by Sirius Red staining, was greater in Etoh vs. FD. Levels of endotoxin, ALT, CYP2E1 and lipid peroxidation markers were also higher (p < 0.01) in Etoh vs. FD. Levels of NF‐κB and mRNA of pro‐inflammatory mediators (TNF‐α, COX‐2, iNOS) and procollagen‐I were increased (p < 0.05) in ethanol‐fed rats. Immunohistochemical analysis showed more intense staining for both iNOS and nitrotyrosine in the centrilobular areas in the Etoh vs. FD groups. The greater area of positive staining for iNOS and nitrotyrosine in Etoh vs. FD was confirmed by Western Blot analysis. An increase in the expression of mRNA for profibrogenic genes (p < 0.05) was seen in ethanol‐fed rats. Conclusions: A voluntary feeding regimen consisting of fish oil and ethanol in female rats is technically less demanding yet produces pathological and biochemical changes similar to those observed with the IG model. Pathological changes include fatty liver, necrosis and inflammation. Increased NF‐κB and mRNA and protein levels of the pro‐inflammatory mediators TNF‐α, COX‐2 and iNOS, coincided with the presence of necroinflammatory changes. The voluntary feeding regimen is proposed as an alternative to the IG model in the study of alcoholic liver injury.  相似文献   
997.

Purpose

Exposure of sclera below the iris in natural head positions is aesthetically undesirable. Studies on post-surgical changes in inferior scleral exposure following orthognathic surgery are scarce and mostly retrospective. The aim of this clinical trial is to examine the effect of Le Fort I osteotomy, a procedure for correction of malocclusion and maxillo-mandibular deformities, on the inferior scleral exposure and overall scleral surface area in skeletal class III patients.

Materials and methods

This trial was performed on 40 eyes of 20 skeletal class III patients undergoing Le Fort I osteotomy without impaction (n = 20 eyes) and with impaction (n = 20 eyes). Standard true-size frontal photography was performed pre-operatively and post-operatively at 6 months. After measuring the overall eye height and the height of visible inferior sclera, the ratio of inferior sclera to overall eye height (S:E) was calculated three times. Also, overall surface area of the sclera was measured three times. The average of three attempts was considered the main measurement. Changes in the sclera after the surgery and between both methods were compared.

Results

The average age of patients (9 men, 11 women) was 24.5 years. Age and gender were balanced between the two groups (P > 0.05). S:E ratios decreased in both groups after surgery (P < 0.05, Wilcoxon test). The decrease was greater in the impaction group (P < 0.05, Mann–Whitney test). Similar results were observed for overall sclera surface areas.

Conclusion

Maxillary advancement, with or without impaction, reduced the inferior scleral exposure and overall scleral surface area. The effect was more pronounced in the impaction group.  相似文献   
998.

Statement of problem

To the authors’ knowledge, while accuracy outcomes of the TRIOS scanner have been compared with conventional impressions, no available data are available regarding the accuracy of digital scans with the Omnicam and True Definition scanners versus conventional impressions for partially edentulous arches.

Purpose

The purpose of this in vitro study was to compare the accuracy of digital implant scans using 2 different intraoral scanners (IOSs) with that of conventional impressions for partially edentulous arches.

Material and methods

Two partially edentulous mandibular casts with 2 implant analogs with a 30-degree angulation from 2 different implant systems (Replace Select RP; Nobel Biocare and Tissue level RN; Straumann) were used as controls. Sixty digital models were made from these 2 definitive casts in 6 different groups (n=10). Splinted implant-level impression procedures followed by digitization were used to produce the first 2 groups. The next 2 groups were produced by digital scanning with Omnicam. The last 2 groups were produced by digital scanning with the True Definition scanner. Accuracy was evaluated by superimposing the digital files of each test group onto the digital file of the controls with inspection software.

Results

The difference in 3-dimensional (3D) deviations (median ±interquartile range) among the 3 impression groups for Nobel Biocare was statistically significant among all groups (P<.001), except for the Omnicam (20 ±4 μm) and True Definition (15 ±6 μm) groups; the median ±interquartile range for the conventional group was 39 ±18 μm. The difference in 3D deviations among the 3 impression groups for Straumann was statistically significant among all groups (P=.003), except for the conventional impression (22 ±5 μm) and True Definition (17 ±5 μm) groups; the median ±interquartile range for the Omnicam group was 26 ±15 μm. The difference in 3D deviations between the 2 implant systems was significant for the Omnicam (P=.011) and conventional (P<.001) impression techniques but not for the True Definition technique (P=.247).

Conclusions

Within the limitations of this study, both the impression technique and the implant system affected accuracy. The True Definition technique had the fewest 3D deviations compared with the other 2 techniques; however, the accuracy of all impression techniques was within clinically acceptable levels, and not all differences were statistically significant.  相似文献   
999.
1000.
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