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71.
Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that is produced mainly by tubular epithelial cells in kidney and contributes to renal interstitial inflammation and fibrosis. More recently, we have demonstrated that urinary MCP-1 excretion is increased in proportion to the degree of albuminuria (proteinuria) and positively correlated with urinary N-acetylglucosaminidase (NAG) levels in type 2 diabetic patients. Based on these findings, we have suggested that heavy proteinuria, itself, probably aggravates renal tubular damage and accelerates the disease progression in diabetic nephropathy by increasing the MCP-1 expression in renal tubuli. In the present study, to evaluate whether urinary MCP-1 excretion is increased in the proteinuric states not only in diabetic nephropathy but also in other renal diseases, we examined urinary MCP-1 levels in IgA nephropathy patients with macroalbuminuria (IgAN group; n = 6), and compared the results with the data obtained from type 2 diabetic patients with overt diabetic nephropathy (DN group; n = 23) and those without diabetic nephropathy (non-DN group; n = 27). Urinary MCP-1 excretion levels in non-DN, DN, IgAN groups were 157.2 (52.8-378.5), 346.1 (147.0-1276.7), and 274.4 (162.2-994.5) ng/g creatinine, median (range), respectively. Expectedly, urinary MCP-1 and NAG excretion levels in DN and IgAN groups were significantly elevated as compared with non-DN group. Therefore, we suggest that MCP-1 expression in renal tubuli is enhanced in proteinuric states,irrespective of the types of renal disease, and that increased MCP-1 expression probably contributes to renal tubular damage in proteinuric states.  相似文献   
72.
Background/Purpose: Recent studies have found that anomalous pancreaticobiliary ductal union (APBDU) is a substantial risk factor for biliary tract cancer at a younger age. DPC-4 (Smad-4) is a new tumor suppressor gene frequently inactivated in pancreatic and bile duct adenocarcinoma. To clarify carcinogenesis in APBDU, the authors investigated possible DPC-4 and K-ras mutations in 35 pediatric patients. Methods: DNA was extracted from biliary tract epithelial cells, which were resected surgically and histologically purified using microdissection. Polymerase chain reaction (PCR) primers were designed specifically for exons 8-11 of DPC-4 (18q21.1) and exons 1-2 of the K-ras oncogene (12p12.1). DNA sequences were determined using the direct DyeDeoxy Terminator Cycle method. Results: Of 35 children, 30 had wild-type DPC-4 and K-ras genes. K-ras mutations were detected in 5 patients, 4 of whom showed epithelial hyperplasia or metaplasia. In a 12-year-old girl with adenocarcinoma arising from a choledochal cyst, K-ras and DPC-4 (homozygous deletion) mutations were identified simultaneously. Conclusions: These results suggest that carcinogenesis in the biliary tract epithelium in APBDU is accompanied by multistep genetic mutational events; K-ras gene mutation occurs early in epithelial hyperplasia or metaplasia, whereas inactivation of the DPC-4 gene accumulates late in the progression of biliary tract adenocarcinoma. J pediatr Surg 38:694-697. [copy ] 2003 Elsevier Inc. All rights reserved.  相似文献   
73.
Yamada K  Miura M  Miyayama H  Sakashita N  Kochi M  Ushio Y 《Surgical neurology》2002,58(5):332-6; discussion 336-7
BACKGROUND: Brain metastasis from pancreatic cancer is extremely rare. Because pancreatic cancer usually has a rapidly progressive nature, the majority of affected patients die from primary lesions before exhibiting clinical signs suggestive of brain metastases. CASE DESCRIPTION: The patient was a 62-year-old man who developed generalized convulsion followed by right hemiparesis accompanied by decreased consciousness level. Computed tomography (CT) scan revealed multiple brain tumors with ring-like contrast enhancement. Stereotactic biopsy disclosed mucinous adenocarcinoma. A marked increase in the serum CA19-9 level was noted, but the patient did not exhibit any other signs of pancreatic disease. Repeated whole body CT scan and ultrasonography demonstrated no primary lesions. The patient died of multi-organ failure during chemotherapy combined with radiation for metastatic brain tumors. Autopsy revealed well-differentiated papillary adenocarcinoma in the pancreatic head and systemic metastases associated with tumor emboli were widely distributed in various organs. CONCLUSION: This patient initially presented only with symptoms of neurologic disorder and no pancreatic symptoms. Moreover, repeated radiologic examinations did not reveal the primary lesion. We considered that the unusual clinical course in our patient may be partly explained by the autopsy findings: diffuse sclerotic changes of the pancreas without swelling. The present report suggests that undetected pancreatic cancer may have been the primary lesion classified as "unknown origin" in some cases of metastatic brain tumors.  相似文献   
74.

Background

Bone mineral density (BMD) loss around femoral implants, particularly in the proximal femur, is a common outcome after total hip arthroplasty. Previous studies reported the prevention of postsurgical decrease in BMD with the use of osteoporosis drug therapy. This randomized study evaluated the efficacy of alendronate and alfacalcidol for preserving BMD over a long-term follow-up.

Methods

Sixty consecutive patients with hip osteoarthritis who had undergone primary cementless total hip arthroplasty were randomly assigned to an alendronate (n = 20), alfacalcidol (n = 18), or control (n = 22) group. Periprosthetic BMD was measured using dual-energy X-ray absorptiometry at 1 week, 1 year, and the current follow-up (minimum 9 years after surgery). Changes in BMD are reported as mean percentages relative to the values at 1 week (baseline reference).

Results

All groups showed a significant decrease in the BMD of the calcar at the current follow-up compared to the values at both 1 week and 1 year postoperatively (P < .001). The BMD values were significantly higher in the alendronate group than in the alfacalcidol and control groups (P < .05). The BMD values at the current follow-up were 76% ± 30% (alendronate group), 64% ± 22% (alfacalcidol group), and 59% ± 22% (control group) of the baseline values.

Conclusion

Our findings demonstrate the efficacy of early administration of alendronate for the prevention of bone loss in the calcar region.  相似文献   
75.
Higher levels of albumin excretion within the normal range are associated with cardiovascular disease in high-risk individuals. Whether incremental increases in urinary albumin excretion, even within the normal range, are associated with the development of hypertension in low-risk individuals is unknown. This study included 1065 postmenopausal women from the first Nurses' Health Study and 1114 premenopausal women from the second Nurses' Health Study who had an albumin/creatinine ratio <25 mg/g and who did not have diabetes or hypertension. Among the older women, 271 incident cases of hypertension occurred during 4 yr of follow-up, and among the younger women, 296 incident cases of hypertension occurred during 8 yr of follow-up. Cox proportional hazards regression was used to examine prospectively the association between the albumin/creatinine ratio and incident hypertension after adjustment for age, body mass index, estimated GFR, baseline BP, physical activity, smoking, and family history of hypertension. Participants who had an albumin/creatinine ratio in the highest quartile (4.34 to 24.17 mg/g for older women and 3.68 to 23.84 mg/g for younger women) were more likely to develop hypertension than those who had an albumin/creatinine ratio in the lowest quartile (hazard ratio 1.76 [95% confidence interval 1.21 to 2.56] and hazard ratio 1.35 [95% confidence interval 0.97 to 1.91] for older and younger women, respectively). Higher albumin/creatinine ratios, even within the normal range, are independently associated with increased risk for development of hypertension among women without diabetes. The definition of normal albumin excretion should be reevaluated.  相似文献   
76.
OBJECTIVE: To compare the health-related quality of life (HRQOL) of persons with a permanent colostomy to that of the general Japanese population and explore the factors influencing HRQOL. DESIGN: A cross-sectional survey. SETTING AND SUBJECTS: A total of 255 persons with an ostomy who attended a meeting of the Japan Ostomy Association in the Kanto region of Japan. INSTRUMENTS: The HRQOL was assessed using Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), Japanese version 1.2. Factors potentially influencing the HRQOL were age, sex, marital status, employment status, number of people in the household, time since colostomy, and diagnosis. METHODS: Questionnaires were distributed to the subjects and SF-36 scores were determined and compared with the corresponding national-norm data by Wilcoxon signed rank sum test. A logistic regression analysis was used to explore the influencing factors. RESULTS: The questionnaire response rate was 66.7%. Subjects with a urostomy or an ileostomy and those with missing data were excluded. Data from 102 subjects with a permanent colostomy were analyzed. The subjects' scores were significantly lower than the national-norm scores in the role-physical and social functioning scales. Being employed was associated with significantly lower scores or associated with a tendency toward lower scores. CONCLUSIONS: Scores in two scales in these subjects were lower than those of national-norm scores. Being employed had a negative impact on the HRQOL of subjects with a permanent colostomy. The results of this study provide reference data for future research and underscore the importance of support for persons with a colostomy.  相似文献   
77.
78.
The prognosis for children with malignant solid tumors has improved dramatically in Japan. During the last two decades, various groups have conducted sequential studies of the treatment of children with neuroblastoma, Wilms' tumor, and hepatoblastoma. Most institutes participated in nonrandomized trials designed to evaluate the safety and efficacy of combination chemotherapy, surgery, and radiotherapy in each group study and treated children with these tumors The results are reviewed and areas for future investigation are identified.  相似文献   
79.
BACKGROUND AND OBJECTIVE: Gold nanoshells are a new class of nanoparticles that can be designed to strongly absorb light in the near infrared (NIR). These particles provide much larger absorption cross-sections and efficiency than can be achieved with currently used chemical chromophores without photobleaching. In these studies, we have investigated the use of gold nanoshells as exogenous NIR absorbers to facilitate NIR laser-tissue welding. STUDY DESIGN/MATERIALS AND METHODS: Gold nanoshells with peak extinction matching the NIR wavelength of the laser being used were manufactured and suspended in an albumin solder. Optimization work was performed on ex vivo muscle samples and then translated into testing in an in vivo rat skin wound-healing model. Mechanical testing of the muscle samples was immediately performed and compared to intact tissue mechanical properties. In the in vivo study, full thickness incisions in the dorsal skin of rats were welded, and samples of skin were excised at 0, 5, 10, 21, and 32 days for analysis of strength and wound healing response. RESULTS: Mechanical testing of nanoshell-solder welds in muscle revealed successful fusion of tissues with tensile strengths of the weld site equal to the uncut tissue. No welding was accomplished with this light source when using solder formulations without nanoshells. Mechanical testing of the skin wounds showed sufficient strength for closure and strength increased over time. Histological examination showed good wound-healing response in the soldered skin. CONCLUSIONS: The use of nanoshells as an exogenous absorber allows the usage of light sources that are minimally absorbed by tissue components, thereby, minimizing damage to surrounding tissue and allowing welding of thicker tissues.  相似文献   
80.

Background/Purpose

Recent biological studies have elucidated the molecular mechanism of muscle development, in which various regulatory factors (myogenic regulatory factors [MRFs]) play key roles during embryogenesis. To investigate the development of anorectal malformations (ARMs), we studied MRF expressions in myogenic cells in the pelvic floor using murine embryos affected with ARM.

Methods

Anorectal malformation embryos were obtained from the 10.5th embryonal day (E10.5) to the 7.0th postnatal day (D7.0) in a natural mutant strain (Sd/+, RSV/Le). Serial frozen sections were prepared for immunohistochemistry using specific antibodies to M-cadherin, myoD, Myogenin, myosin heavy chain, and alfa-actin molecule.

Results

In normal mice, embryonal caudal somites differentiated into myogenic stem cells and migrated to the pelvic floor between E11.0 and E14.0. In the ARM mice, however, caudal somites were irregularly arranged and MRF expressions in myogenic cells were markedly decreased in the dorsocaudal region at E11.5 to E13.0, leading to hypoplastic pelvic floor muscles.

Conclusions

The maldevelopment of pelvic floor muscles in ARM is derived from a deficient supply of myogenic stem cells, with impaired MRF expression. These results suggest that myogenic stem cells, available from bone marrow contents, may be used for postnatal muscle regeneration to reinforce the pelvic floor muscle function in children with ARM.  相似文献   
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