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11.
Scott L Kominsky Michele Doucet Kelly Brady Kristy L Weber 《Journal of bone and mineral research》2007,22(1):37-44
Bone metastases develop in approximately 30% of patients with RCC, and the mechanisms responsible for this phenomenon are unknown. We found that TGF-beta1 stimulation of RCC bone metastasis cells promotes tumor growth and bone destruction possibly by stimulating paracrine interactions between tumor cells and the bone. INTRODUCTION: Bone metastasis is a frequent complication and causes marked morbidity in patients with renal cell carcinoma (RCC). Surprisingly, the specific mechanisms of RCC interaction with bone have been scarcely studied despite the inability to prevent or effectively treat bone metastasis. Bone is a reservoir for various growth factors including the pleiotropic cytokine TGF-beta1. TGF-beta1 has been shown to have tumor-supportive effects on advanced cancers and evidence suggests its involvement in promoting the development of breast cancer bone metastasis. Here, we studied the potential role of TGF-beta1 in the growth of RCC bone metastasis (RBM). MATERIALS AND METHODS: To inhibit TGF-beta1 signaling, RBM cells stably expressing a dominant-negative (DN) TGF-betaRII cDNA were generated. The in vivo effect of TGF-beta1 on RBM tumor growth and osteolysis was determined by histological and radiographic analysis, respectively, of athymic nude mice after intratibial injection of parental, empty vector, or DN RBM cells. The in vitro effect of TGF-beta1 on RBM cell growth was determined after TGF-beta1 treatment by MTT assay. RESULTS: TGF-beta1 and the TGF-beta receptors I and II (TGF-betaRI/II) were consistently expressed in both RBM tissues and cell lines. Inhibition of TGF-beta1 signaling in RBM cells significantly reduced tumor establishment and osteolysis observed in vivo after injection into the murine tibia, although no effect on tumor establishment was observed after injection of RBM cells subcutaneously or into the renal subcapsule. Treatment of five RBM cell lines with TGF-beta1 in vitro either had no effect (2/5) or resulted in a significant inhibition (3/5) of cell growth, suggesting that TGF-beta1 may promote RBM tumor growth indirectly in vivo. CONCLUSIONS: TGF-beta1 stimulation of RBM cells plays a role in promoting tumor growth and subsequent osteolysis in vivo, likely through the initiation of tumor-promoting paracrine interactions between tumor cells and the bone microenvironment. These data suggest that inhibition of TGF-beta1 signaling may be useful in the treatment of RBM. 相似文献
12.
Kim Mudd Mary Elizabeth Bollinger Van Doren Hsu Michele Donithan Arlene Butz 《The Journal of asthma》2006,43(8):597-600
Background. Medication adherence impacts healthcare utilization. Pharmacy records are useful to establish fill patterns. Objective. Use pharmacy records to establish medication patterns fill patterns for comparison to healthcare utilization. Methods. Pharmacy records of 175 children with persistent asthma were collected and compared to healthcare utilization. Results. Majority of subjects had significant healthcare utilization, low numbers of rescue medications, and poor controller medication fill rates. Those with more rescue medications had more healthcare utilization and more controller medications. Conclusions. Pharmacy fill patterns demonstrate few rescue and/or controller medication fills. Those with more rescue medications reported increased healthcare utilization despite controller medications. 相似文献
13.
14.
Pietro Rubegni MD Sara Poggiali MD Aldo Cuccia MD Maurizio Biagioli MD Michele Fimiani MD 《Dermatologic surgery》2004,30(12P2):1539-1542
Background. Striated palmoplantar keratoderma or Brunauer-Fohs-Siemens syndrome is a very rare, focal, nonepidermolytic palmoplantar keratoderma with autosomal inheritance. Unlike other palmoplantar keratodermas, no association with visceral or skin cancer has ever been reported.
Objective. We report a case of malignant melanoma arising in the hyperkeratotic lesions on the right heel of a patient with striated palmoplantar keratoderma. The lesion was completely excised; our patient also underwent sentinel lymph node biopsy and then was treated with high-dose interferon adjuvant therapy.
Methods. Sentinel lymph node biopsy incision was made in elliptical fashion, long enough to harvest a full-thickness skin graft to cover the wide local excision defect. The skin graft was defatted by sharp dissection. Several perforations were made in graft and it was secured in place with sutures and bolster dressing.
Results. At follow-up, the grafted skin showed hyperkeratotic changes but no local or systemic signs of the disease was observed.
Conclusion. The association between striated palmoplantar keratoderma and acral melanoma is discussed. 相似文献
Objective. We report a case of malignant melanoma arising in the hyperkeratotic lesions on the right heel of a patient with striated palmoplantar keratoderma. The lesion was completely excised; our patient also underwent sentinel lymph node biopsy and then was treated with high-dose interferon adjuvant therapy.
Methods. Sentinel lymph node biopsy incision was made in elliptical fashion, long enough to harvest a full-thickness skin graft to cover the wide local excision defect. The skin graft was defatted by sharp dissection. Several perforations were made in graft and it was secured in place with sutures and bolster dressing.
Results. At follow-up, the grafted skin showed hyperkeratotic changes but no local or systemic signs of the disease was observed.
Conclusion. The association between striated palmoplantar keratoderma and acral melanoma is discussed. 相似文献
15.
Salvatore Serra Giuliana Brunetti Giovanni Vacca Carla Lobina Mauro A M Carai Gian Luigi Gessa Giancarlo Colombo 《Alcohol》2003,29(2):101-108
Results of a recent study have demonstrated that exposure to multiple ethanol concentrations and repeated ethanol deprivation periods in Indiana ethanol-preferring (P) rats resulted in the development of an alcohol deprivation effect (ADE; the temporary increase in voluntary ethanol intake after a period of deprivation from ethanol) characterized by consumption of intoxicating amounts of ethanol. The current study was designed to possibly extend these results to Sardinian alcohol-preferring (sP) rats, generated with the same selective program previously used for P rats. To this aim, ethanol-naive sP rats were exposed initially to the home cage four-bottle choice [10%, 20%, and 30% (vol./vol.) ethanol solutions and water] for eight consecutive weeks. Subsequently, rats were divided into two groups: The first group had continuous access to the four-bottle regimen (nondeprived rats), and the second group was exposed to five cycles of 14-day periods of deprivation from ethanol and 14-day periods of reexposure to the four-bottle regimen. An ADE developed after each deprivation period. However, the extra intake of ethanol was limited to the first hour of each reaccess period. Magnitude of ADE did not change with repeated periods of deprivation. However, a shift in preference toward the two highest concentrations of ethanol solutions was evident from the first reexposure to ethanol and was maintained throughout the study. These results provide further evidence on the heterogeneity of ethanol-drinking behavior among rat lines selectively bred for high ethanol preference and consumption. 相似文献
16.
17.
Angelo Cagnacci Gian Benedetto Melis Renza Soldani Anna Maria Paoletti Marco Gambacciani Adriana Spinetti Piero Fioretti 《Maturitas》1991,13(4):283-296
The neuroendocrine and clinical effects of transdermal 17β-estradiol (rated at 50 μg/day; TTS 50) were studied in 40 postmenopausal women; ten additional postmenopausal women did not receive any drugs. The changes in LH and rectal temperature induced by the infusion of the opioid antagonist naloxone (10 mg i.v. bolus plus 10 mg/h for 4 h) were used to evaluate the central activity of endogenous opioid peptides. TTS 50 increased opioid activity, as evidenced by the restoration of the LH response (P < 0.01) and the enhancement of the hypothermic effect (P < 0.05) of naloxone. A greater reduction in hot flushes was observed in TTS 50-treated subjects than in untreated women, with the maximal effect of TTS 50 achieved after 3 months of therapy. TTS 50 did not modify the concentrations of circulating lipids, glucose or liver enzymes but reduced the biochemical parameters indicative of bone reabsorption. Bone density of the distal radius significantly increased during TTS 50 (P < 0.02), reaching its maximum value after 6 months of therapy. Thereafter bone density declined, but more slowly than in untreated women.
Our data suggest that TTS 50 has marked neuroendocrine effects, that it diminishes the incidence of hot flushes and reduces bone demineralization. By contrast, it has a very little, if any, metabolic impact on the liver or on glucose and lipid metabolism. 相似文献
18.
Marie-Francoise Dresse Michele David Heather Hume Herve Blanchard Pierre Russo Nicolas Van Doesberg Georges E. Rivard 《Pediatric hematology and oncology》1991,8(4):329-334
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA. 相似文献
19.
This paper reports a method of acquiring and codifying branching profiles of axonal arborizations. Using a microcomputer interfaced with a motor driven microscope scanning stage, an acquisition strategy was developed. This strategy allows large profiles (covering up to 1250 mm2) to be measured with an accuracy of a few microns. Each histological section is associated with a specific coordinate system. This system was found to locate the profiles with high precision and reliability in the x-y microscope stage. The overall tracing accuracy of the system is fully discussed. 相似文献
20.
L Santoro A Perretti A Filla G De Michele B Lanzillo F Barbieri C Crisci P G Rippa G Caruso 《Journal of the neurological sciences》1992,113(1):43-49
An electrophysiologic and histologic study was performed on 18 patients affected by early onset cerebellar ataxia with retained tendon reflexes (EOCA). Sensory and motor conduction velocity (SCV, MCV) was measured along peripheral nerves in all patients, somatosensory (SSEP) and brainstem auditory evoked potentials (BAEP) were recorded in 13; cortical stimulation (CS) in 12, and sural nerve biopsy in 4 patients were also performed. The results as a whole allow a division of EOCA patients into 2 groups: with (7 patients) and without (11 patients) peripheral neuropathy. Among EOCA patients with neuropathy a differential diagnosis with Friedreich's disease patients was not possible according to BAEPs and CS, while SSEPs could differentiate 2 out 5 patients in whom they were performed. 相似文献