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81.
Amniotic membrane (AM), the most internal placental membrane, has unique properties including antiadhesive effects, bacteriostatic, wound protection and pain-reduction properties, as well as epithelialization initialization capacities. Furthermore, AM is widely available and less costly than other bioengineered skin substitutes. In a prospective pilot study, we evaluated the safety, feasibility, and the effects on healing of AM graft in 15 patients with chronic venous leg ulcers. AM grafts were prepared from placentas harvested during cesarean section. All grafted AM had adhered to the wound bed 7 days after being applied with a 100% engraftment rate. The percentage of granulation tissue increased significantly (from 17% on day 0 to 69% on day 14, p<0.0001), along with a significant decrease of fibrinous slough (from 36% at day 0 to 16% at day 14, p<0.001). A significant clinical response occurred in 12 patients (80%) including complete healing (20%) in three during the 3-month follow-up period. The ulcer surface area decreased significantly from a mean value (+/- standard deviation) of 4.59 +/- 2.49 cm(2) at baseline to 2.91+/-2.01 cm(2) on day 30 (p<0.001). All patients experienced a significant reduction of ulcer-related pain rapidly after AM transplantation. No adverse events were recorded. AM transplantation seems to function as a safe substrate, promoting proper epithelialization while suppressing excessive fibrosis. Further advantages of biotherapy with AM are its easy and low-cost production, and that it can be applied as an ambulatory treatment without immobilization. AM transplantation may thus be considered to be an alternative method for treating chronic leg ulcers.  相似文献   
82.
BACKGROUND: The present retrospective study aims to provide additional evidence supporting the fact that waist circumference, in severe obesity, is not a good clinical marker to identify individuals with the metabolic syndrome or an altered metabolic profile. METHODS: Relationships between waist circumference and metabolic profile of pre- (n=165) and postmenopausal (n=43) severely obese women were compared to associations observed in pre- (n=52) and postmenopausal (n=35) moderately obese women. RESULTS: Results showed that abdominal obesity assessed by waist circumference was more highly correlated with fasting glycemia, HDL-cholesterol and the cholesterol/HDL-cholesterol ratio in moderately than in severely obese women, before menopause. After menopause, waist circumference was not a valuable predictor of metabolic abnormalities in both groups. Moreover, when waist circumference was included as a criterion of the metabolic syndrome (as defined by the NCEP ATP III guidelines) in severely obese women, the prevalence of this metabolic condition was over-estimated by 72%. CONCLUSION: These results emphasize the uselessness of waist circumference to assess the prevalence of the metabolic syndrome or an altered metabolic profile in severely obese women.  相似文献   
83.
BACKGROUND: Mucinous, medullary, and tubular carcinomas are uncommon types of breast cancer whose rarity does not permit large single-institution studies or randomized trials to define optimal treatments. In this study, we evaluated the long-term outcomes of breast-conserving therapy (BCT) for these subtypes of breast cancer and compared them with those for invasive ductal carcinoma. METHODS: In our institutional database of patients who received BCT from 1965 to 1999, 1,643 patients with stage I to II mucinous (61), medullary (37), tubular (60), and invasive ductal (1,485) histologies were identified. The clinical and pathologic features of the 4 groups were evaluated and compared with respect to local-regional recurrence rates, disease-free survival, and overall survival (OS). RESULTS: No statistically significant differences were found in the local-regional failure rate among the 4 groups (10.6-year median follow-up). Only patients with tubular carcinoma had better 5- and 10-year OS rates (P = .013). In multivariable analysis, factors associated with improved OS included age at or below 50 years, negative nodal status, use of chemotherapy or hormonal therapy, and tubular histology. CONCLUSIONS: BCT for mucinous, medullary, or tubular carcinoma resulted in similar local-regional failure rates to that for invasive ductal carcinoma. Tubular carcinoma patients had the most favorable OS. BCT is an appropriate treatment strategy for early-stage mucinous, medullary, and tubular carcinomas.  相似文献   
84.
Atypical lipomatous tumor/well-differentiated liposarcomas and dedifferentiated liposarcomas are characterized by the amplification of MDM2 and CDK4 genes. To evaluate the accuracy of fluorescence in situ hybridization (FISH) analysis in the differential diagnosis of adipose tissue tumors, we investigated MDM2-CDK4 status by FISH, real-time polymerase chain reaction (PCR) [quantitative PCR (Q-PCR)] and immunohistochemistry (IHC) in a series of 200 adipose tumors. First, we evaluated MDM2-CDK4 amplification and expression in a series of 94 well-defined adipose tissue tumors. Results showed that FISH was interpretable in 45 of 50 cases (90%), and was more specific and sensitive than Q-PCR and IHC. We then used the same techniques as complementary diagnostic tools in a series of 106 adipose and soft tissue tumors of unclear diagnosis to distinguish between (i) lipomas and atypical lipomatous tumor/well-differentiated liposarcomas, (ii) malignant undifferentiated tumors and dedifferentiated liposarcomas, and (iii) a variety of benign tumors and liposarcomas. Our results indicate that although helpful, IHC alone is often insufficient to solve diagnostic problems. FISH and Q-PCR methods gave concordant results and were equally informative in most cases. However, the proportion of noninterpretable cases was slightly higher with FISH than with Q-PCR. When tumor cells represented a minor component of the tumor tissue, such as with inflammatory tumors, FISH was more powerful than Q-PCR by allowing visualization of individual cells. In conclusion, we recommend that the evaluation of MDM2-CDK4 amplification using FISH or Q-PCR be used to supplement IHC analysis when diagnosis of adipose tissue tumors is not possible based on clinical and histologic information alone.  相似文献   
85.
Sir, We report the occurrence of thrombotic microangiopathy (TMA)that may be directly related to vascular endothelial growthfactor (VEGF) Trap treatment, a fully humanized recombinantfusion protein containing extracellular portions of the extracellulardomains of two different VEGF receptors, VEGFR-1 and VEGFR-2.VEGF Trap is currently under evaluation in combination withLV5FU2-CPT11 in a  相似文献   
86.
This study investigated the impact of catalase (Cat) overexpression in renal proximal tubule cells (RPTCs) on nuclear factor erythroid 2–related factor 2 (Nrf2) stimulation of angiotensinogen (Agt) gene expression and the development of hypertension and renal injury in diabetic Akita transgenic mice. Additionally, adult male mice were treated with the Nrf2 activator oltipraz with or without the inhibitor trigonelline. Rat RPTCs, stably transfected with plasmid containing either rat Agt or Nrf2 gene promoter, were also studied. Cat overexpression normalized systolic BP, attenuated renal injury, and inhibited RPTC Nrf2, Agt, and heme oxygenase-1 (HO-1) gene expression in Akita Cat transgenic mice compared with Akita mice. In vitro, high glucose level, hydrogen peroxide, and oltipraz stimulated Nrf2 and Agt gene expression; these changes were blocked by trigonelline, small interfering RNAs of Nrf2, antioxidants, or pharmacological inhibitors of nuclear factor-κB and p38 mitogen-activated protein kinase. The deletion of Nrf2-responsive elements in the rat Agt gene promoter abolished the stimulatory effect of oltipraz. Oltipraz administration also augmented Agt, HO-1, and Nrf2 gene expression in mouse RPTCs and was reversed by trigonelline. These data identify a novel mechanism, Nrf2-mediated stimulation of intrarenal Agt gene expression and activation of the renin-angiotensin system, by which hyperglycemia induces hypertension and renal injury in diabetic mice.  相似文献   
87.

Purpose

To compare the healthcare costs of women with unilateral breast cancer who underwent contralateral prophylactic mastectomy (CPM) with those of women who did not.

Methods

We conducted a retrospective study of 904 women treated for stage I–III breast cancer with or without CPM. Women were matched according to age, year at diagnosis, stage, and receipt of chemotherapy. We included healthcare costs starting from the date of surgery to 24 months. We identified whether care was immediate or delayed (CPM within 6 months or 6–24 months after initial surgery, respectively). Costs were converted to approximate Medicare reimbursement values and adjusted for inflation. Multivariable regression analysis was performed to evaluate the effect of CPM on total breast cancer care costs adjusting for patient characteristics and accounting for matched pairs.

Results

The mean difference between the CPM and no-CPM matched groups was $3,573 (standard error [SE] $455) for professional costs, $4,176 (SE $1,724) for technical costs, and $7,749 (SE $2,069) for total costs. For immediate and delayed CPM, the mean difference for total costs was $6,528 (SE $2,243) and $16,744 (SE $5,017), respectively. In multivariable analysis, the CPM group had a statistically significant increase of 16.9 % in mean total costs compared with the no-CPM group (p < 0.0001). Human epidermal growth factor receptor 2/neu-positive status, receipt of radiation, and reconstruction were associated with increases in total costs.

Conclusions

CPM significantly increases short-term healthcare costs for women with unilateral breast cancer. These patient-level cost results can be used for future studies that evaluate the influence of costs of CPM on decision making.  相似文献   
88.
BackgroundThe prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in cystic fibrosis (CF) patients has increased and MRSA seems to be associated with a poorer prognosis. The aim of this study was to assess the prevalence and clinical consequences of MRSA and methicillin-susceptible Staphylococcus aureus (MSSA), associated or not associated with Pseudomonas aeruginosa (PA).MethodsIn a retrospective study on 419 sputum producer patients (293 adults and 126 children > 7 years of age), we recorded patient characteristics, lung function, nutritional status, IV antibiotics and hospitalisations, the presence of SA and/or PA and FEV1 decline over 2 years.ResultsSA was found in 72% of the patients: MSSA in 68.2% of children and 48.8% of adults; MRSA in 17.5% of children and 17.8% of adults. Sixty percent of MRSA patients and 60.4% of MSSA patients also harboured PA. The rate of deterioration of clinical status of the various groups, as assessed from respiratory function, IV antibiotic courses and hospitalisations, increased in the order: no SA/no PA, MSSA alone, MRSA alone, MSSA/PA, MRSA/PA, and PA alone. Nutritional status did not differ between groups. Results were roughly similar for children and adults. The yearly FEV1 decline was significantly higher only for MRSA/PA patients (p = 0.03) compared to no SA/no PA patients.ConclusionClinical condition of CF patients with MSSA only or MRSA only appeared similar, whereas MRSA/PA patients had more severe respiratory function than MSSA/PA patients. In CF patients, MRSA might be more deleterious than MSSA only when associated with PA.  相似文献   
89.
HYPOTHESIS: Resection of the nipple-areolar complex (NAC) for central breast cancers that involve the nipple or areola, with postoperative radiation therapy, adheres to the oncologic principles established for breast conservation surgery of other breast cancers. Good or excellent cosmetic results can be achieved. The rate of ipsilateral breast recurrence will be similar to that seen with peripheral breast cancers. The indications for breast conservation surgery can be safely extended to include patients with breast cancers that involve the NAC. DESIGN: Retrospective medical record review; follow-up patient questionnaire. SETTING: Community teaching hospital. PATIENTS: Fifteen patients, aged 46 to 88 years, whose central breast cancers involved the NAC precluding preservation of the NAC. INTERVENTIONS: Nipple-areolar complex resection, postoperative radiation therapy. MAIN OUTCOME MEASURES: Ipsilateral breast recurrence, survival, cosmesis. RESULTS: Ten patients had subareolar cancers that directly involved the nipple or areola; 5 patients had Paget disease of the nipple. Average tumor size was 1.6 cm (range, 0.2-3.5 cm). With a mean follow-up of 32 months (range, 4-109 months), there has been only 1 recurrence (7%), which was treated successfully by modified radical mastectomy. All 15 patients are alive and free of disease. Cosmetic results are satisfactory to excellent, as judged by both the patients and the surgeons. CONCLUSIONS: Nipple-areolar complex resection for central subareolar cancers that directly involve the NAC, as well as for Paget disease of the nipple, extends the indications for breast conservation in other areas of the breast, and with acceptable cosmesis.  相似文献   
90.
The Department of Defense Familial Breast/Ovarian Cancer Research Project has offered genetic counseling and testing for BRCA1 and BRCA2 on a research basis to patients meeting specific diagnostic criteria, with risk for BRCA1 and BRCA2 mutations calculated based on the Couch model. In 2.5 years, 250 patients were evaluated and 101 patients met criteria requirements, including 33 who met criteria in more than one category. Ninety patients elected to undergo DNA testing. In this group of 90 patients, 14 mutations (15.5%) and 16 unclassified variants (17.7%) were identified. The most common inclusion criteria were onset of breast/ovarian cancer before age 45 years (n = 32) and onset of breast/ovarian cancer before age 45 years with strong family history (n = 21). However, when number of mutations and unclassified variants found were compared separately across all diagnostic criteria (including those of more than one capacity) using the chi 2 statistic, no significant differences were seen among the categories to suggest that one criterion was more predictive of mutations or variants than another. Couch risk values for patients with mutations showed a mean of 14% and ranged from 3.2 to 43.5% (range for all patients, 1.2-69.7%). These findings emphasize the importance of using multiple diagnostic criteria and suggest that a Couch risk value of > 3% may be useful in selecting patients for testing. The data also underscore the necessity of genetic counseling in the testing process, particularly given the large number of unclassified variants diagnosed and their uncertain status for disease predisposition.  相似文献   
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