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971.

Objective

The present study explored the three-dimensional spatial arrangements of the neurons and glial cells within the medial prefrontal cortex (mPFC) of rats.

Methods

It evaluated the arrangement for differences after stress with or without treatment with curcumin and sertraline using second-order stereology. Orientator method was applied to obtain isotropic uniform random sections of mPFC. The pair correlation g(r) and cross-correlation functions were estimated by counting dipole probes superimposed on histological sections of mPFC.

Results

The mean total volume of neurons and glial cells was 0.80 (0.05) and 0.40 (0.07), respectively in the control group. The corresponding values decreased by 50% in the stressed group. The curve of g(r) for the neurons and glial cells showed a wider gap between the stressed rats'' mPFC. Theses indicate a negative correlation (repulsion) between the neurons and glial cells in the stressed rats. Evaluation of the cross-correlation function of the neurons and glial cells also showed a negative correlation in the stressed group. The estimated values of the global degree of order in the spatial point pattern for neurons and glial cells were 0.62 and 0.20 in control and stressed animals, respectively. Curcumin and sertraline protected the spatial arrangements of the cells after stress induction in rats. In addition, the volume of the neurons and glial cells remained unchanged after stress.

Conclusion

Dissociation of the neurons and glial cells can is seen at some places in the stressed rats'' cortex. However, the spatial arrangement of the cells was remained unchanged in curcumin+stress and sertraline+stress rats.  相似文献   
972.
973.
Exercise testing induces fatal thromboembolism from mechanical mitral valve   总被引:1,自引:0,他引:1  
Thromboembolism is still one of the most important complications of prosthetic heart valves. Embolism to a major coronary branch is rare, but acute proximal occlusions can be fatal, even when the coronary arteries are otherwise normal and intervention is rapid. We report a fatal complication of an exercise test in a patient who had a St. Jude bileaflet mitral valve. After an exercise test, a 42-year-old woman with a mechanical prosthetic valve had a severe hemodynamic collapse with acute ST segment changes. Coronary angiography showed a totally occluded left main coronary artery with TIMI grade 0 to 1 flow. Rapid injection of contrast material and the passage of a floppy guidewire through the thrombus restored a TIMI grade 3 flow. Angiography showed no coronary atherosclerostic involvement. Despite successful coronary reperfusion, intra-aortic balloon counterpulsation, and intensive medication, the patient died. This case demonstrates that exercise testing should be applied with great caution in patients with prosthetic valves, and only after a careful evaluation of valve function. We recommend transesophageal echocardiography prior to exercise testing in these patients.  相似文献   
974.
Impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) are two risk groups for type 2 diabetes. Type 2 diabetes is characterized by both impaired insulin secretion and insulin resistance but their relative contribution to the development of hyperglycemia may differ due to heterogeneity of the disease. Combined glucose intolerance (CGI), on the other hand, seems to represent a more advanced stage of prediabetes that bears a distinctly higher risk of progression to diabetes and its comorbidities. This study has the aim to compare isolated IFG and CGI categories with respect to the degree of early phase insulin secretion abnormalities and insulin resistance. Subjects who had IFG (fasting glucose: 110-126 mg/dl) were included in the study. A 75-g oral glucose tolerance test (OGTT) with insulin response was done and subjects were classified according to the WHO criteria. Six subjects were excluded because they had diabetic glucose tolerance. A total of 66 patients (53.4 +/- 11.1 years, female/male: 48/18) were divided into two groups according to their glucose tolerance in OGGT (Group 1: isolated IFG and group 2: CGI). Early phase insulin secretion was measured by intravenous glucose tolerance test (IVGTT) and OGTT. Insulin resistance was assessed by the R value of the homeostasis model assessment (HOMA). We did not find any statistically significant difference between groups according to age, gender, body mass index (BMI), fasting glucose, fasting insulin, insulin-AUC (0-180 min) and HOMA-R values. In OGGT there was no statistically significant difference between 0', 30', 60' and 90' insulin levels of the groups; only 120' and 180' insulin levels were higher in CGI than in IFG group (p<0.05). In IVGTT, there was no statistically significant difference between glucose levels of the groups. Furthermore, insulin response to intravenous glucose was higher in IFG than in CGI (p<0.05). Our data demonstrate that isolated IFG and CGI are similar with respect to the degree of insulin resistance, and that subjects with CGI had a more prominent deficit in early phases of insulin secretion.  相似文献   
975.
Increased deposition of the extracellular matrix components, particularly collagen, is a central phenomenon in liver fibrosis. Stellate cells, the central mediators in the pathogenesis of fibrosis are activated by free radicals, and synthesize collagen. Melatonin is a potent physiological scavenger of hydroxyl radicals. Melatonin has also been shown to be involved in the inhibitory regulation of collagen content in tissues. At present, no effective treatment of liver fibrosis is available for clinical use. We aimed to test the effects of melatonin on dimethylnitrosamine (DMN)-induced liver damage in rats. Wistar albino rats were injected with DMN intraperitoneally. Following a single dose of 40 mg/kg DMN, either saline (DMN) or 100 mg/kg daily melatonin was administered for 14 days. In other rats, physiologic saline or melatonin were injected for 14 days, following a single injection of saline as control. Hepatic fibrotic changes were evaluated biochemically by measuring tissue hydroxyproline levels and histopathogical examination. Malondialdehyde (MDA), an end product of lipid peroxidation, and glutathione (GSH) and superoxide dismutase (SOD) levels were evaluated in blood and tissue homogenates. DMN caused hepatic fibrotic changes, whereas melatonin suppressed these changes in five of 14 rats (P < 0.05). DMN administration resulted in increased hydroxyproline and MDA levels, and decreased GSH and SOD levels, whereas melatonin reversed these effects. When melatonin was administered alone, no significant changes in biochemical parameters were noted. In conclusion, the present study suggests that melatonin functions as a potent fibrosuppressant and antioxidant, and may be a therapeutic choice.  相似文献   
976.
BACKGROUND: Over 50% of patients with chronic heart failure (CHF) have sleep-disordered breathing (SDB). Any variation in the type of SDB in CHF will have implications for patient management. Currently there is good evidence for treatment of obstructive sleep apnea (OSA) in CHF with continuous positive airway pressure; however, for central sleep apnea (CSA) the treatment is less clear. AIMS: The aim of this study was to investigate the variation in the severity and type of SDB (OSA vs. CSA) throughout 4 consecutive nights in CHF patients with SDB. METHODS: Nineteen male CHF patients (mean+/-sd: age 61+/-9 years; left ventricular ejection fraction: 34+/-10% and percent predicted peak VO2: 67+/-19%) underwent cardiorespiratory monitoring in their own home throughout 4 consecutive nights. RESULTS: There was minimal variation in apnea-hypopnea index (AHI) throughout 4 nights in CHF patients with SDB [intraclass correlation coefficient (95% confidence interval (CI)): 0.97 (95% CI 0.76 and 0.97)]. Eight patients [42% (95% CI 20% and 64%)] demonstrated a shift in the type of their SDB, from CSA to OSA or vice versa; these patients had significantly smaller neck circumference (group mean+/-sd) 42+/-2 vs. 44+/-2 cm; p=0.04), and had significant variation in the central AHI [intraclass correlation coefficient: 0.51 (95% CI 0.16 and 0.85)]. CONCLUSIONS: A single night of cardiorespiratory monitoring is representative of moderate-to-severe SDB in patients with CHF. However, a high proportion of patients shift their type of SDB over 4 nights. These findings may have implications for the management of SDB in CHF.  相似文献   
977.

Background:

Pediatric neck mass is a frequent cause for surgical consultation. Neck masses can be simply classified into congenital, inflammatory, and neoplastic. Although most of the cases are due to benign processes, malignant causes must not be overlooked. The aim of this study is to assess the paediatric neck masses in Iraqi patients highlighting the distribution of cases according to their demographic characteristics and etiology.

Patients and Methods:

A cross-sectional observed study is conducted in the Department of Pediatric Surgery, at the Central Teaching Hospital of Pediatrics in Baghdad from April 2008 to March 2009. Sixty four patients with neck masses aged 14 years and below were examined and managed. The underlying causes of the neck masses were addressed and categorized.

Results:

Among the 64 patients, 42 (65.6%) were male. The inflammatory group represents 57% of the cases, while the malignant neoplasm accounts for approximately 10% of the conditions mainly due to lymphoma 5 (7.8%). Sixteen patients (25%) fall in the congenital group, in which the thyroglossal duct cyst was the commonest type. Wound infection developed in two patients, while one patient with cystic hygroma showed recurrence.

Conclusion:

Pediatrics neck masses are distributed in categories that similar in pattern and distribution in the world except the infectious/inflammatory category that shows variation in distribution in respect to the socioeconomic status. The surgical intervention and procedures are related to the facility as well as to the experience.Key words: Inflammatory, neoplastic, pediatrics neck masses, reactive lymphadenitis  相似文献   
978.
Visceral basidiobolomycosis is an unusual fungal infection of viscera caused by saprophyte Basidiobolus ranarum. It is very rare in healthy children and poses a diagnostic challenge due to the non-specific clinical presentation and the absence of predisposing factors. We report a case of gastrointestinal basidiobolomycosis in a 4-year-old healthy girl who presented with a short history of abdominal pain, bleeding per rectum, fever, and weight loss. The diagnosis was based on high eosinophilic count, classical histopathology findings of fungal hyphae (the Splendore-Hoeppli phenomenon), and positive fungal culture from a tissue biopsy. Fungal infection was successfully eradicated with a combined approach of surgical resection of the infected tissue and a well-monitored course of antifungal therapy. The atypical clinical presentation, diagnostic techniques, and the role of surgery in the management of a rare and lethal fungal disease in an immunocompetent child are discussed.Key words: Basidiobolomycosis, child, fungal infection, gastrointestinal, immunocompetent  相似文献   
979.
OBJECTIVE: To determine the frequency and clinical characteristics of osteoarticular complications of brucellosis in an endemic region in Iran. METHODS: In a prospective study we evaluated 245 patients with brucellosis diagnosed between January 2004 and December 2005. Patients included were those older than 8 years of age and who had clinical features suggestive of brucellosis and specific antibodies at significant titers, and/or positive blood or body fluid culture for Brucella species. A bone scan was performed in those with a clinical suspicion of osteoarticular involvement. RESULTS: Seventy patients (28.6%) had osteoarticular complications. Sacroiliitis was the most common complication (75.7%), followed by spondylitis (21.4%) and peripheral arthritis (8.6%). Spondylitis was the most common osteoarticular complication in the elderly. Relapses occurred in five (2%) patients, three of them with spondylitis. CONCLUSIONS: Osteoarticular disease is the most common complication of brucellosis in Western Iran. Sacroiliitis is the most common form of osteoarticular complication. With the use of a proper treatment regimen, the prospect for recovery is good.  相似文献   
980.
BM remains an important source of stem cells. The BM characteristics change with age but the estimation of CD34 calculation of one CD34+ cell per 100 nucleated cells is used for all donors including pediatric donors in the operating room before getting the actual CD34 count. In order to see whether this formula is applicable for pediatric donors, we designed a retrospective study to see the affect of the age and sex on the BM NCC, CD34 count, and CD34/NCC ratios. Ninety‐eight BM collections from 91 related donors were evaluated retrospectively (median age: nine yr [1.5–54 yr]; M/F: 41/50). A significant negative correlation was found between the donor age and NCC (r = −0.229, p < 0.05), CD34 count (r = −0.563, p < 0.01), and CD34/NCC (r = −0.664, p < 0.01). The negative correlation for CD34 count and CD34/NCC persisted in female and male donor groups. When donors younger than 16 yr of age were compared with the older donor group, the median NCC, median CD34 count, and CD34/NCC were significantly lower in the older group (p < 0.01). Age and sex have to be taken into consideration to avoid unnecessary high‐volume collections and increased operating room time in the younger donors.  相似文献   
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