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61.
BACKGROUND: Cystinosis is an autosomal recessive disorder, caused by mutations of the lysosomal cystine carrier cystinosin, encoded by the CTNS gene (17p13). The concomitant intralysosomal cystine accumulation leads to multi-organ damage, with kidneys being the first affected. Altered mitochondrial oxidative phosphorylation has been demonstrated in animal proximal tubules loaded with cystine dimethyl ester, mimicking cystine accumulation in cystinosis, but has not been confirmed in cells of patients with cystinosis. Furthermore, the link between cystine accumulation and mitochondrial damage is also missing. We hypothesized that cytosolic cysteine deficiency resulting in intracellular glutathione (GSH) shortage might be involved in cellular dysfunction in cystinosis. METHODS: Components of the gamma-glutamyl cycle were measured in cultured skin fibroblasts (n = 9) and polymorphonuclear (PMN) leukocytes (n = 15) derived from patients with cystinosis and compared with the values in cultured fibroblasts (n = 9) and PMN cells (n = 18) of healthy controls. RESULTS: Cystine content in cystinotic fibroblasts and PMN cells was significantly elevated compared with the controls, consistent with the lysosomal cystine accumulation in these cells. Although no reduction of total intracellular GSH content was found in cystinotic cells, it inversely correlated with cystine levels. Furthermore, GSH disulfide (GSSG) was elevated in cystinotic cells, resulting in an increased GSSG/total GSH (%) ratio. No relationship between intracellular cystine and GSH was found in control fibroblasts and PMN cells. CONCLUSION: An elevated GSSG/total GSH (%) ratio might indicate increased oxidative stress present in cystinotic cells. Inverse correlation between cystine accumulation and intracellular GSH content indicates that under stress conditions such as intensive energy demand or increased oxidative insult, cystinotic cells may be more prone to GSH depletion.  相似文献   
62.
BACKGROUND: The use of suctioned fat grafts for correction of soft tissue defects is a widespread procedure in esthetic and reconstructive surgery. The main disadvantage of this simple and sensible procedure is the unpredictable absorption rate of the fat graft. A lot of research has been performed aiming for enhancement of the take of the fat grafts. OBJECTIVE: Our study was performed to find if there is any favorable donor site for fat harvesting. METHODS: This in vivo experiment using the nude mice model enables the study of the long-term survival of human fat in an animal model. The fat was harvested from three donor areas: the thigh, abdomen, and breast of a 48-year-old woman who came for an elective esthetic procedure. After centrifugation, 1 cc of fat was injected subcutaneously into the scalp of the nude mouse. There were 15 mice in each of the three groups, according to the selected donor sites. The animals were sacrificed 16 weeks after the procedure. The extracted fat was evaluated in terms of weight, volume, and six histologic parameters: integrity, vascularization, cyst formation, fibrosis, necrosis, and inflammation. RESULTS: This study could not find any statistically significant differences between the three investigated donor sites in the evaluated parameters. CONCLUSION: On the basis of this study, there is no favorable area for harvesting fat grafts. The donor site can be chosen according to the preference of the surgeon and the patient.  相似文献   
63.
Background Scleroderma is characterized by abnormal growth of connective tissue, often manifested with hard and tight skin. The viscous properties of the skin are impaired, and the main histologic changes include a thicker dermis, absence of pilosebaceous units, and a decreased space between collagen bundles. Often these patients have wound healing problems.
Objective The objective was to demonstrate a case of scleroderma that had deep phenol perioral peeling and fat injection into the lips. According to our bibliographic search, this is the first report in the English literature of using these modalities in scleroderma patients.
Methods A 64-year-old woman suffering from scleroderma for more than 20 years came for improvement of her perioral appearance. We decided to manage her deep perioral wrinkles by deep peeling using the Baker formula and concomitantly to use autologous fat injection to augment her thin lips.
Results The healing of our patient after these two interventions was uneventful, and satisfactory results have been obtained.
Conclusion Based on our experience, this intervention may be suggested for patients suffering from scleroderma after a detailed explanation of the possible wound healing difficulties is provided to the patients.  相似文献   
64.
Disease status assessment of neuroblastoma patients requires computed tomography (or magnetic resonance imaging), bone scan, metaiodobenzylguanidine (MIBG) scan, bone marrow tests, and urine catecholamine measurements. There is no clinical experience concerning the evaluation of these patients by means of technetium-99m (99mTc)-somatostatin analog scintigraphy. Furthermore, these radiopharmaceuticals are promising imaging agents owing to their lower cost, availability, dosimetry, and ease of preparation. An 8-year-old boy already diagnosed with stage-IV neuroblastoma received chemotherapy. In the follow-up, after obtaining the parents’ informed consent, iodin 131 (131I)-MIBG and 99mTc-6-hydrazinopyridine-3-carboxylic acid (HYNIC)-octreotide scans were done on separate days to evaluate tumor extension. Even as the 131I-IBG scan showed mild diffuse uptake in the projection of both lung hili, the 99mTc-HYNIC-octreotide scan showed multiple axial and appendicular bone uptakes and paravertebral, abdominal, mediastinal, and supraclavicular ganglionar uptakes. The 99mTc-HYNIC-octreotide showed much more lesion extension than the 131I-MIBG. Therefore, 99mTc-HYNIC-octreotide may be a promising radiopharmaceutical for the evaluation of neuroblastoma patients. This finding justifies the pre liminary evaluation of this tracer in the context of a clinical trial.  相似文献   
65.
BACKGROUND: In chronic renal failure (CRF), hyperphosphatemia and an elevated calcium-phosphate product are associated with vascular calcification and increased cardiovascular morbidity and mortality. Previous data have demonstrated that 3-month treatment of uremic rats with sevelamer was associated with less nephrocalcinosis compared to calcium carbonate (CaCO3), despite similar control of serum phosphorus, calcium-phosphorus product (Ca x P product), and secondary hyperparathyroidism. There was no evidence of aortic calcification after 3 months of uremia (J Am Soc Nephrol 13:2299-2308, 2002). The present studies explore the influence of sevelamer and CaCO3 on cardiovascular and kidney calcifications in long-term experimental uremia over 6 months. METHODS: Normal and 5/6 nephrectomized rats (U) were fed a high phosphorus (HP) diet for 6 months. Two phosphate binders, CaCO3 and sevelamer, were administered and their influence on hyperphosphatemia, secondary hyperparathyroidism, kidney/myocardial/aortic calcification, and renal function was compared. RESULTS: All uremic rats began the study with the same degree of renal failure. Sevelamer was as effective as CaCO3 in reducing serum phosphorus, Ca x P product, and attenuating secondary hyperparathyroidism. Despite similar serum cholesterol levels, rats in the U-HP + sevelamer group had markedly lower calcium deposition in the myocardium and aorta (myocardium, 72 +/- 4 microg/g wet tissue; aorta, 736 +/- 156 microg/g wet tissue) compared to rats in either the U-HP + CaCO3 group (myocardium, 179 +/- 48, P < 0.05; aorta, 1308 +/- 343, P < 0.05) or the U-HP group (myocardium, 98 +/- 10, NS; aorta, 2150 +/- 447, P < 0.05). Dual immunohistochemical analysis for calcium and endothelial cell markers demonstrated that myocardial calcium deposition was intravascular within capillaries. Furthermore, calcium deposition in the kidney of uremic rats treated with sevelamer (582 +/- 111 microg/g wet tissue) was lower than that found in uremic rats treated with CaCO3 (1196 +/- 180 microg/g wet tissue). Sevelamer-treated rats had less deterioration in renal function with an associated lower serum creatinine, higher creatinine clearance, and less proteinuria. There was no difference in overall mortality between the three experimental groups. CONCLUSION: In long-term experimental CRF, in addition to controlling serum phosphorus and secondary hyperparathyroidism as efficiently as CaCO3, treatment with the phosphate-binder sevelamer attenuates vascular and kidney calcification.  相似文献   
66.
Malignant mesothelioma of the peritoneum is a rare neoplasm with a rapidly fatal course. The median survival range is from 5 to 12 months in untreated cases with little improvement seen in patients receiving multimodality therapy. Although most cases occur in the fifth and sixth decades, peritoneal mesothelioma can be seen in any age group. Approximately 30% of all mesotheliomas arise solely from the peritoneum. Asbestos exposure, primarily of the crocidolite variety, has been implicated in the pathogenesis of this malignancy, as was established in South Africa in the 1960s. Half of reported cases have a history of asbestos exposure. The diagnosis of peritoneal mesothelioma is often delayed, in part because of the usually long latent period (peaking at 40-45 years from the time of initial exposure to asbestos) and because the common presenting symptoms of weight loss, usually with a full abdomen, malaise, and abdominal discomfort, are mild and nonspecific. This paper aim is to present a case report regarding a patient diagnosed with malignant peritoneal mesothelioma with an unpredictable evolution.  相似文献   
67.
BACKGROUND: Bone loss is a frequent and well-known complication in the first months after renal transplantation, but there are no data considering body composition variables (bone, fat, and lean mass) together in transplant recipients. This prospective study investigated total body bone density, fat mass, and lean mass before and 1, 2, 3, 4, and 6 months after renal transplantation in male patients who underwent hemodialysis. METHODS: Twenty consecutive renal transplant male patients aged 23-64 years (mean, 40 years; median, 41 years) received one of two immunosuppressive therapies (cyclosporine+methylprednisolone, or cyclosporine+methylprednisolone+azathioprine). The bone, fat, and lean mass of the total body and its related subregions were assessed by means of dual X-ray photon absorptiometry. Mixed factorial analysis of variance for repeated measurements was used for the statistical analysis. RESULTS: During the 6 months after transplantation, there was a reduction in trabecular bone mass in the spine, ribs, and pelvis total body subregions; the reduction was statistically significant in the last two subregions. There was no statistically significant difference in the lean mass of the total body or its subregions over time, but there was a statistically significant increase in the fat mass of the total body and all of its subregions; the increase in total and trunk fat mass seemed to be greater in the patients not receiving azathioprine. CONCLUSIONS: Up to 6 months after renal transplantation in male patients who underwent hemodialysis, there is a marked increase in fat mass, a significant loss of trabecular bone mass, and no change in cortical bone and lean mass.  相似文献   
68.
The objective of this study was to explore whether the items from a specific outcome measure, that is, Disabilities of the Arm, Shoulder, and Hand (DASH), for quantifying limb symptoms and functions in musculoskeletal disorders fit into the framework of the International Classification of Functioning, Disability and Health (ICF). All DASH items were compared to the ICF according to eight linking rules. Two groups of researchers performed the linking independently, and the results were compared by correlation. The 30 DASH items and four items from the optional modules were linked to 63 ICF categories and 11 chapters: 15 categories belong to the ICF body functions component and 48 to the activities and participation component. There were no items coded under the components body structure or environmental factors. Kappa index showed an agreement of 0.73 (p<0.001). The results showed that the content of the DASH does link well with the ICF framework. Clinicians and researchers must attend to the fact that certain domains and categories from the ICF are not covered by the DASH. Limitations of the instrument may be overcome by simultaneously using other instruments that address the intended content.  相似文献   
69.
70.
The extended brow lift: the toucan technique   总被引:1,自引:0,他引:1  
Brow ptosis is the main consequence of aging in the upper third of the face. Many methods have been described to correct it: skin excisions of the brow hairline, skin excisions of the forehead natural creases, skin trimmings of the temporal, coronal, or forehead hairline flaps, and endoscopic methods [1,15,17,18,24,26,27]. The authors created a procedure which is based on a forehead-temporal subcutaneous flap and a muscular relocation. It treats the brow ptosis and its surrounding area—temporal ptosis, upper and lower lateral eyelid ptosis, crow's feet—and at the same time improves the sclera show or ectropion. The method preserves the sideburn and the temporal hairline and can reduce the width between the temporal hairline and the lateral end of the eyebrow. The method produces maximum improvement, with high-quality scars and minimal evidence of surgery. The procedure is called "The Toucan Technique," due to the shape of the skin resection which looks like a toucan bird [11,13,14].  相似文献   
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