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51.
BACKGROUND: Glomerular hyperfiltration is considered as one of the pathophysiological mechanisms for the development of diabetic nephropathy. Oxidative stress is enhanced in patients with diabetes mellitus. Reportedly, nitric oxide (NO) might be involved in the pathogenesis of hyperfiltration. We investigated the relationship between hyperfiltration and NO system, and malondialdehyde (MDA) levels in Type 2 diabetics with/without microalbuminuria. METHODS: In 39 microalbuminuric, 29 normoalbuminuric Type 2 diabetic patients and 32 healthy controls, serum creatinine, nitrite, nitrate, urinary microalbumin, nitrite, nitrate, plasma MDA and estimated glomerular filtration rate (EGFR) values, calculated according to the Cockcroft and Gault formula, were recorded. RESULTS: Serum and urine NO levels were higher in both microalbuminurics and normoalbuminurics than controls. There were no significant differences in EGFR between groups. However, hyperfiltration was determined in 31% of normoalbuminurics and 20% of microalbuminurics. Serum and urine NO levels were higher in patients with hyperfiltration. Plasma MDA levels were significantly elevated in both microalbuminurics and normoalbuminurics when compared with controls. Serum glucose and microalbuminuria were positively correlated in microalbuminuric diabetics. Serum NO levels were also positively correlated with EGFR in both normoalbuminurics and microalbuminurics. HbA1c levels were positively correlated with both urinary albumin excretion and plasma MDA levels in normoalbuminuric diabetics. CONCLUSIONS: Hyperglycemia is associated with an increased NO biosynthesis and lipid peroxidation. Increased oxidative stress may contribute to the high NO levels in Type 2 diabetes. Furthermore, the high NO levels may lead to hyperfiltration and hyperperfusion, which in turn leads to an increase in urinary albumin excretion and thus causes progression of nephropathy in early Type 2 diabetes.  相似文献   
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OBJECTIVES: Obesity is a major public health problem with an increasing prevalence. Although coronary artery bypass grafting (CABG) operations are now performed with low morbidity and mortality rates, obesity is still assumed to be an important risk factor for morbidity and mortality at these operations but there is no precise approach to define it as a risk factor. The aim of this study is to evaluate the effects of obesity on the clinical outcome of the CABG operations. METHODS: A total of 1206 patients, who underwent isolated CABG operation under cardiopulmonary bypass were evaluated retrospectively. The patients were divided into three groups. Group I was normal weight, with body mass index (BMI) of 18-24.9 kg/m(2), group II was overweight, with a BMI of 25-29.9 kg/m(2), and group III was obese, with a BMI of >30 kg/m(2). The clinical data of three groups were evaluated in aspects of postoperative morbidity and mortality. RESULTS: Except for the superficial wound infections, there were no differences in postoperative mortality and morbidity rates between the three groups. Obesity was not found to be an important risk factor for postoperative morbidity and mortality. CONCLUSIONS: Despite the perception that obesity increases the risk of mortality and morbidity in CABG operations, the clinical outcome of these patients are not so different from other patients. We may say that obese patients can be safely operated.  相似文献   
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Background: Biopsy and electrical activity recordings of the corpus cavernosum are 2 new diagnostic methods for the evaluation of impotent men. We evaluated the corpus cavernosum ultrastructure and electromyography (EMG) recordings from patients with erectile dysfunction.
Methods: Twenty erectile dysfunction patients with veno-occlusive dysfunction underwent a detailed history, physical examination, biochemical tests, hormonal analysis, injection of an intracavernous vasoactive agent (60 mg papaverine-HCI), color penile Doppler ultrasonography, cavernosometry/ cavernosography and corpus cavernosum electromyography (CC-EMG). Thirteen patients underwent total vein ligation and 7 had penile prosthesis implantations. Tissue samples were obtained during surgery from both corpora cavernosa and examined by transmission electron microscopy. Control corporal tissue samples were taken from 3 cadavers.
Results: In 15 patients, CC-EMG recordings were 15.6 ± 0.65 μV in the flaccid state, which decreased in 13 patients after papaverine (5.61 ± 0.25 μV; P < 0.001). Five patients with diabetes mellitus had low amplitudes in the flaccid state (5.26 ± 0.45 μV), which did not vary significantly after a papaverine injection (4.99 |pL 0.75 μV). The pathology of the corpus cavernosum biopsy specimens revealed a smooth muscle cell thickened basal membrane, dilated rough endoplasmic reticulum, and increased numbers of fibroblasts, but ultrastructurally normal endothelial cells lining the and sinusoids. There was no difference between samples from diabetic or nondiabetic patients, or from either side of the corpora cavernosa. The only pathologic change observed in the controls was mitochondrial swelling.
Conclusion: CC-EMG is less invasive and a valuable method in patients with erectile dysfunction, whereas no specific findings were observed from penile biopsy specimens.  相似文献   
55.
Analysis of metastatic ovarian tumors from extragenital primary sites   总被引:2,自引:0,他引:2  
Turan T  Aykan B  Koc S  Boran N  Tulunay G  Karacay O  Erdogan Z  Kose F 《Tumori》2006,92(6):491-495
AIMS AND BACKGROUND: The aim of this study was to evaluate patients with metastatic ovarian tumors from extragenital primary sites. METHODS: The medical records of 75 patients were reviewed retrospectively for age at diagnosis, presenting symptoms, preoperative tumor marker levels, preoperative diagnostic workup, operative technique, intraoperative evaluation, frozen-section and pathology results, laterality of metastasis, and primary tumor site. The specific impact of metastasis from colorectal and gastric primary sites on laterality, gross features and dimensions of ovarian mass, volume of ascites and tumor marker levels was investigated. RESULTS: Primary sites were stomach (37.3%), colorectal region (28%), lymphoma (12%), breast (6.7%), biliary system (2.7%), appendix (1.3%) and small intestine (1.3%). It was not possible to identify the primary tumor site in 8 (10.7%) patients. Bilateral metastasis was found in 86.4% patients; 42.7% of the metastatic ovarian tumors were Krukenberg tumors; 50.7% of the ovarian masses were solid. Frozen section was confirmed by postoperative pathological results in 98% of the patients. The mean preoperative serum levels of tumor markers were 298.7 U/mL, 178 U/mL and 113.3 U/mL for CA 125, CA 19-9 and CA 15-3, respectively. CA 125 levels were above 35 U/mL in 81.3% of the patients. The presence of ascites was more frequent in ovarian tumors originating from colorectal and gastric primaries. CONCLUSIONS: Surgery is essential for the diagnosis of the primary tumor and necessary for relief of symptoms. The identification of the primary site is required to plan adequate treatment.  相似文献   
56.
Background: Omental adipose tissue specimens of female rats that were fed a high fat (HF) diet were evaluated stereologically and histopathologically. To our knowledge, there is no stereological study on numerical density, nuclear height and volume of adipocytes in omental adipose tissue in the female rat fed a HF diet in the literature. Method: 20 female Spraque Dawley rats were used in the study. 10 of the animals were fed HF diet consisting of 30% of calories from fat for 3 months. The remaining 10 rats, the control group, were fed a normal diet. After the experimental procedure, all animals were anesthetized and omental adipose tissues in the same area were dissected and fixed for the histochemical process using a mixture of 3% glutaraldehyde and 1% osmium tetraoxide in 0.1 M phosphate buffer. After embedding of tissues in araldite CY 212, semi-thin and thin sections were cut. The semi-thin sections were stained with toluidine blue. The physical dissector counting method was used for estimation of numerical density and nuclear height of adipocytes. Cavalieri principle was used for the estimation of adipocyte volume; volume fraction approach was applied to find the volume fraction of adipose tissue components. Results: The mean numerical density of adipocytes in the HF diet group was significantly higher than the control. The mean nuclear height of adipocytes was also very high in the HF diet group. The volume fraction of adipose mass was increased whereas the extracellular matrix volume fraction was reduced in the HF diet group compared to the controls. The mean volume of adipocytes in the HF diet group was also significantly higher than in the control group. At the light microscopy level, it was found that adipocytes were enlarged and gaining irregular shape in the HF diet group. Thicker basal lamina and electron dense lipid content were also found in this group at the electron microscopy level. Conclusion: Lipid content and number of adipocytes in the adipose tissue of HF diet rats were higher than in the controls. Thus, HF diet induces increase in body weight via both hypertrophy and hyperplasia of adipocytes.  相似文献   
57.
Breast cancer is the most common cancer and the second leading cause of cancer deaths among women in developed countries. Bone is a frequent site of metastatic disease with a stage-dependent incidence. Most women with breast cancer are at risk of osteoporosis due to their age or their breast cancer treatment. Scintigraphy enables imaging of the entire skeleton with high sensitivity but limited specificity. The false positive rate varies from 1.6% to as high as 22%, while the false negative rate varies from 0.96% to 13%. We observed a 70-year-old woman with a diagnosis of breast cancer and a false negative bone scan despite extensive bone metastases. She was under alendronate treatment for osteoporosis at the time. The false negative finding might be due to a transient phenomenon of alendronate, a bisphosphonate cleared from the plasma by uptake into bone and by renal excretion. 99mTc-MDP is eliminated via the same pathways, and therefore competition may occur between the two substances. Another possible explanation for the false negative bone scan could be that bone metastases, indicating hematogenous tumor spread, are detected earlier by CT scan or MRI than by bone scan. Breast cancer patients under bisphosphonate treatment for osteoporosis must be carefully evaluated for bone metastasis during radionuclide studies with 99mTc-MDP.  相似文献   
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Background: The aim of this study is to evaluate the levels of serum lipoprotein‐associated phospholipase A2 (Lp‐PLA2) and high‐sensitivity C‐reactive protein (hsCRP) in association with periodontal disease and hyperlipidemia. Methods: A total of 123 subjects with hyperlipidemia and 68 systemically healthy controls were included in the study. Subjects with hyperlipidemia were divided into two groups: the suggested‐diet (HD) and prescribed‐statin (HS) groups and then into three subgroups: the healthy (HDh and HSh), gingivitis (HDg and HSg), and periodontitis (HDp and HSp) groups. Periodontal parameters were recorded and included the plaque index, gingival index (GI), probing depth (PD), clinical attachment level (CAL), and percentage of sites with bleeding on probing (BOP). Fasting venous blood samples were obtained, and serum lipid, Lp‐PLA2, and hsCRP levels were evaluated. Results: Median values for the GI, PD, BOP(%), and CAL in the HSg group were statistically significantly higher than those in the HDg and systemically healthy with gingivitis (Cg) groups. The HSp group had higher percentages of BOP compared to those of the chronic periodontitis and HDp groups. The HDg group had higher serum Lp‐PLA2 and hsCRP levels compared to those of the Cg and HSg groups. The ratio of total cholesterol to high‐density lipoprotein cholesterol (TC/HDL) was significantly associated with the GI, PD, and BOP(%) in both groups with hyperlipidemia. Serum Lp‐PLA2 and hsCRP levels were significantly correlated with TC/HDL, the GI, PD, and BOP(%) in the HD group. Conclusions: Serum Lp‐PLA2 and hsCRP levels may play an important role in the association between periodontal disease and hyperlipidemia, and the control of these mediators may affect the inflammatory control of patients with hyperlipidemia and periodontal disease.  相似文献   
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