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71.
Lung development is a highly orchestrated process characterized by timed expression and activation of growth factor and protease/antiprotease systems. This interplay is essential in regulating vasculogenesis, alveolarization, and epithelial to mesenchymal transition during lung development. Alterations in the proteolytic/antiproteolytic balance of the lung have been associated with several respiratory diseases characterized by changes in the lung extracellular matrix (ECM). Here, we characterized the expression pattern of matrix metalloproteases (MMP) and their inhibitors, the tissue inhibitors of metalloproteases (TIMP), in human and mouse lung development. Using MMP/TIMP expression arrays, RT-PCR, Western Blotting, and ELISA analyses, we demonstrate that fetal human lung is characterized by a dominant proteolytic profile with high MMP-2 and little TIMP-3 expression. Adult human lung, in contrast, exhibits a more anti-proteolytic profile with decreased MMP-2 and increased TIMP-3 expression. MMP-14, MMP-20, TIMP-1, and TIMP-2 were constitutively expressed, irrespective of the developmental stage. Similar results were obtained using mouse lungs of different developmental stages, with the addition that in mouse lung, TIMP-2 and TIMP-3 were upregulated as lung development progressed. Exposure of neonatal mice to chronic hypoxia (10% O2), a stimulus that leads to an arrest of lung development, resulted in upregulation of MMP-2 with a concomitant downregulation of TIMP-2. These results provide a comprehensive analysis of MMP and TIMP expression during human and mouse lung development. MMP-2, TIMP-2, and TIMP-3 may be key regulatory enzymes during lung development, possibly through their complex action on ECM components, membrane receptor ectodomain shedding, and growth factor bioactivity.  相似文献   
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73.

Purpose

Bladder cancers are frequently treated with combination chemotherapy that includes methotrexate (MTX). The development of drug resistance is a common problem in treatment of bladder cancers. We tested if the status of p53 and/or pRb affects the development of MTX resistance in bladder epithelial cell lines.

Materials and Methods

We used two isogeneic sets of cell lines in which we manipulated the status of p53 and/or pRb by transformation with Human Papillomavirus (HPV) E6 and/or E7 or with a transdominant TP53 mutant (TP53 sup 143). One series of isogeneic origin was derived from normal human uroepithelial cells (HUC), and the other was derived from a human transitional cell carcinoma (TCC). Cell lines with p53 and/or pRb alterations were cultured for six months while increasing the MTX concentration in each line, as resistance developed.

Results

Two cell lines with both pRb and p53 alterations, alpha E6/E7-HUC and alpha E7-HUCp53mu, acquired the greatest resistance (750 nM) to MTX. One line with p53 loss, E6-TCC#10, acquired intermediate resistance (500 nM), while two lines, alpha E7-HUC and E7-TCC#10, with altered pRb but wildtype p53, showed low levels of MTX resistance (125 nM and 80 nM, respectively). Two clear mechanisms of MTX resistance were identified. All five MTX resistant cell lines showed altered uptake of MTX. In addition, two of five MTX resistant cell lines, both with altered p53, showed dihydrofolate reductase (DHFR) amplification.

Conclusions

p53 alteration increases the risk for development of drug resistance by both DHFR amplification and altered MTX transport in transformed human bladder epithelial cell lines.  相似文献   
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75.

INTRODUCTION

Loin pain haematuria syndrome is a common problem with complications including opiate dependence. Morbidity treatments include intra-ureteric capsaicin infusion, nephrectomy, autotransplantation and nephrolysis. We explored the use of flexible cystoscopic infusion of intra-ureteric bupivicaine.

PATIENTS AND METHODS

Patients presenting with chronic loin pain underwent urological and nephrological evaluation. Bupivicaine (0.5%, 20 ml) was infused via an intra-ureteric catheter under flexible cystoscopic guidance. Repeat infusions were offered if indicated.

RESULTS

Sixteen of 17 patients with 1-year follow-up responded and were satisfied. Twelve of these required repeat infusions (mean, 2.9 infusions). The procedures were well tolerated by all patients without adverse effects.

CONCLUSIONS

Intra-ureteric bupivicaine infusion has a place in the management of patients with chronic renal pain. It offers a minimally invasive alternative to other treatments. This procedure warrants further investigation within a randomised, controlled trial setting.  相似文献   
76.
77.
The purpose of the study described in this article was to evaluate the extent to which selected behavioral, social, and affective factors contribute to self-reported epilepsy self-efficacy. Participants completed three assessments 3 months apart, with only those completing both the first and second assessments included in this analysis. Self-efficacy scores at the second assessment were regressed on the behavioral, social, and affective characteristics ascertained at the first assessment. The analysis revealed that self-management, depressive symptoms, and seizure severity explain the most variance in self-efficacy; patient satisfaction and stigma are less important predictors; and social support and regimen-specific support are not significant predictors. The results provide direction for identifying people with low levels of self-efficacy and highlighting areas that might help enhance self-efficacy in persons with epilepsy.  相似文献   
78.
79.
The scientific knowledge base that supports clinical decisions about perioperative fluid management continues to evolve. However, despite these advancements in the understanding of the physiology of fluid replacement, the definition of 'optimal' perioperative fluid management remains a matter of clinical judgment. With an appreciation of the many factors, both sensible and insensible, that contribute to changes in blood and extracellular fluid volume during surgery, clinicians have tried to create reproducible and generally applicable formulas for replacement of fluid during surgery. These formulas have been challenged recently by the introduction of new tools for monitoring cardiopulmonary function, by the implementation of monitor-guided protocols for fluid management, and, more recently, by clinical data suggesting that fluid restriction may improve surgical outcomes in some clinical settings. The relative ease of pre-identified fluid replacement protocols is being slowly replaced by data-guided interventions that take into account a variety of factors. Clinicians are therefore required to tailor their fluid replacement strategies based on preoperative patient characteristics, the type of surgery and even the type of anesthetic that is utilized. Some of the benefits of this new approach range from relatively 'minor' outcomes such as diminished nausea after surgery to preventing postoperative complications such as wound breakdown and cardiopulmonary failure.  相似文献   
80.
Adolescents with malignancy represent a unique population in oncology that traditionally has received care at a variety of institutions. Recent data have shown that clinical trial involvement and patient outcomes in this age group may be influenced by the type of hospital at which they are treated. This article examines factors influencing the location of treatment of patients aged 15 to 19 years from selected areas in Ohio. Patients 15 to 19 years of age with malignancy from the selected 45 counties between 1996 and 1999 were identified from the Ohio Cancer Incidence and Surveillance System database. Factors analyzed included specific diagnosis, age, race, and treating institution. A total of 169 patients were identified, with 46.7% treated at pediatric institutions, 24.8% at adult academic centers, and 28.5% at community hospitals. Diagnosis influenced treatment location: leukemias, central nervous system tumors, and sarcomas were treated more often at pediatric hospitals, whereas melanoma was more often treated at adult academic centers. Patient age and distance from an academic center were also found to affect the location of treatment. Specific diagnosis, age, and geographic location influence the site of treatment of adolescent patients. Efforts to improve survival and increase enrollment in clinical trials must take these factors into account.  相似文献   
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