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1.
BACKGROUND AND PURPOSE: Although indomethacin has been demonstrated to prevent germinal matrix and intraventricular hemorrhage in clinical and animal studies, the mechanism of action of this agent to prevent hemorrhage remains unclear. Previous studies have demonstrated both that the microvessels in the germinal matrix of newborn beagle pups undergo basement membrane maturation during the first 4 postnatal days and that indomethacin may promote laminin deposition in tumor cell culture systems. METHODS: We employed the newborn beagle pup model to test the hypothesis that indomethacin may stimulate laminin deposition in germinal matrix microvessels. Newborn pups were randomized to receive either 0.1 mg/kg/dose i.p. indomethacin or an equal volume of saline diluent. Pups received doses of study medication once a day for 1, 2, or 3 days and were studied on postnatal days 1, 2, 3, or 4. Pups were anesthetized and systemically perfused with buffered formalin; the brains were removed and prepared for immunohistochemical study. RESULTS: Sections stained with Bandeiraea lectin demonstrated that there was no difference in germinal matrix vessel density among the postnatal ages studied; similarly, there were no differences in vessel density between saline- and indomethacin-treated animals at any postnatal age. Quantification of germinal matrix stained intensity by confocal microscopy demonstrated significant increases in indomethacin-treated pups for both laminin staining at postnatal days 2 (p = 0.05) and 3 (p = 0.0009) and type V collagen staining at postnatal day 2 (p = 0.011). Although staining for beta 1 integrins increased across postnatal ages, there were no differences between saline- and indomethacin-treated animals. CONCLUSIONS: These data suggest that indomethacin may stimulate basement membrane deposition in the germinal matrix microvessels of newborn beagle pups to prevent germinal matrix and/or intraventricular hemorrhage.  相似文献   
2.
Cystic lesions of the thyroid are common findings. Although many thyroid cysts are of benign, some cases of hemorrhagic degenerative changes occur in neoplastic nodules, mostly follicular neoplasms and papillary carcinomas. The occurrence of hemorrhagic changes in medullary carcinomas has never been documented with aspirative cytological and histological pictures to the best of our knowledge. A case of medullary thyroid carcinoma with a large central hemorrhagic cyst is described, and the literature regarding the pathogenesis of this regression and the occurrence of cystic neoplasms in the thyroid is reviewed.  相似文献   
3.
We evaluated the efficacy of a PCR-reverse cross-blot hybridization assay, a test which permits identification of mycobacteria by means of species-specific probes and a Mycobacterium-specific probe, for early detection of negative BACTEC MGIT 960 mycobacterial cultures. Aliquots of 549 cultures were collected 7 days after the culture media were inoculated with various clinical specimens and tested with the molecular assay. PCR results were compared to those obtained at the end times with the BACTEC MGIT 960 system. Of the 549 specimens analyzed, 484 were found to be negative and 64 were found positive by both methods; one specimen, found to be positive by the BACTEC MGIT 960 system, was identified as negative by the molecular assay. In view of its high negative predictive value (99.8%), the PCR-reverse cross-blot hybridization assay appears to be a valid tool for early detection of negative BACTEC MGIT 960 cultures.  相似文献   
4.
This study was carried out to evaluate the rate of recovery and time required for detection of mycobacteria from pulmonary and extrapulmonary human clinical samples, by using a fluorescence-quenching-based oxygen sensor (BACTEC 9000 MB; Becton Dickinson Microbiology Systems, Sparks, Md.). The results were compared with those obtained by microscopy, conventional culture in Lowenstein-Jensen (LJ) medium, and a BACTEC radiometric system (BACTEC 460 TB; Becton Dickinson). Of the 779 clinical samples processed, 364 from pulmonary sites and 415 from extrapulmonary sites, 62 (7.9%) were positive for mycobacterial isolates; of the positive samples, 59 (95.1%) were detected with the fluorescent BACTEC 9000 MB system, 57 (91.9%) were detected with the radiometric system (BACTEC 460 TB), and 43 (69.3%) were detected with LJ conventional culture. The mean times to detection of all mycobacteria with BACTEC 9000 MB and BACTEC 460 TB were similar (10.3 and 10.0 days, respectively). The results obtained indicate that the nonradiometric BACTEC (BACTEC 9000 MB) system is as efficient as Bactec 460 TB and significantly more efficient than LJ for the rapid recovery of mycobacteria from both pulmonary and extrapulmonary clinical specimens. Though the BACTEC 9000 MB system is recommended for respiratory specimens, we demonstrated that it can be successfully used also for recovery of mycobacteria from clinical specimens from various extrapulmonary sites.  相似文献   
5.
Annals of Surgical Oncology - The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to...  相似文献   
6.
7.
A molecular analysis of drug-resistant isolates of Mycobacterium tuberculosis was done in a population with a high prevalence of human immunodeficiency virus infection. Seventy-one consecutive isolates were tested for genotypic resistance to isoniazid, rifampicin, streptomycin, and ethambutol by polymerase chain reaction-single strand conformation polymorphism analysis and automated sequencing of target regions. Phenotypic and genotypic resistance to isoniazid, rifampicin, streptomycin, and ethambutol were detected in 23.4%, 11.2%, 7%, and 5.6% of isolates and in 87%, 88%, 40%, and 100% of resistant isolates, respectively. Specificity was 100% for all target regions. When rpoB, katG, and ahpC mutation analysis were combined, 86% of resistant isolates to any drug were identified. No mutations in inhA were found in isoniazid-resistant isolates. Molecular detection of drug resistance, particularly for isoniazid and rifampicin, may represent a sensitive and very specific technique. The strategy of selecting rpoB, katG, and ahpC to quickly identify most resistant isolates, with a relevant saving of resources, is warranted.  相似文献   
8.
9.

Background

The efficacy and safety of self-expandable metallic stent (SEMS) placement as a bridge to elective surgery or definitive palliation versus emergency operation to treat colorectal obstruction is debated. This study aimed to evaluate the outcomes of patients with colorectal obstruction treated using different strategies.

Methods

Subjects admitted to the authors’ department with colorectal obstruction (n = 134) were studied prospectively. They underwent endoscopic stenting as a bridge to elective surgery (SEMS group: n = 49) or for definitive palliation (n = 34). A total of 51 patients underwent immediate surgery without stenting (NO-SEMS). Treatment was decided by the senior on-call surgeon.

Results

Placement of SEMS was technically successful in 95.3 % and clinically successful in 98.7 % of cases. The short-term complications in the SEMS group were perforation (n = 1, 1.2 %), migration (n = 4, 4.9 %), occlusion (n = 4, 4.9 %), colon bleeding (n = 3, 3.7 %), and abdominal pain (n = 6, 7.4 %). The postoperative complication rate was 32.7 % in the SEMS group versus 60.8 % in the NO-SEMS group (P = 0.005), with a significant reduction in wound infections (26.5 vs 54.9 %; P = 0.004), abdominal abscess (14.3 vs 39.2 %; P = 0.006), respiratory morbidity (10.2 vs 37.3 %; P = 0.002), and intensive care treatment (10.2 vs 33.3 %; P = 0.007). The median postoperative hospital stay was 10 versus 15 days (P = 0.001). The in-hospital mortality rate in both groups was 2 %. Long-term follow-up evaluation showed less incisional hernia (6.3 vs 22.0 %; P = 0.04) and definitive stoma formation (6.3 vs 26.0 %; P = 0.01) in the SEMS group than in the NO-SEMS group, respectively. Kaplan–Meier survival curves showed a benefit for the SEMS group (log-rank test, 0.004). The long-term SEMS-related complication rate for the palliative patients was 43.8 %. The hospital readmission rate for SEMS complications was 34.4 %. Overall clinical success was 81.2 %.

Conclusions

In case of colorectal obstruction, endoscopic colon stenting as a bridge to elective operation should be considered as the treatment of choice for resectable patients given the significant advantages for short- and long-term outcomes. Palliative stenting is effective but associated with a high rate of long-term complications.  相似文献   
10.

Introduction

The Y-box binding protein-1 (YB-1) is a multifunctional oncoprotein involved in the proliferation and aggressiveness of cancer cells. The aim of this study was to determine whether strong YB-1 expression in neoplastic cells of colorectal liver metastases (CRLM) may have an impact on liver disease-free survival following liver resection.

Materials and Methods

Immunohistochemistry was performed to evaluate YB-1 in 66 patients who underwent liver resection for CRLM. YB-1 expression was classified as weak (low-staining intensity) and strong (high-staining intensity).

Results

YB-1 expression was observed in the cytoplasm of all CRLM. YB-1 expression was weak in 17 patients (25.8 %) and strong in 49 patients (74.2 %). Liver recurrence rate was significantly higher in the strong than in the weak expression group: 55.1 vs. 23.5 % (p?=?0.023). Multivariable logistic regression analysis showed that YB-1 strong expression was the only independent risk factor for liver recurrence. The 5-year specific liver disease-free survival rate was 76.0 % in the weak expression group and 41.5 % in the strong expression group (p?=?0.034). These results were not influenced by clinical prognostic factors of tumor recurrence.

Conclusions

This is the first study showing that the degree of YB-1 expression in tissue specimens of CRLM predicts liver recurrence following liver resection.  相似文献   
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