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31.
Primary glioblastoma multiforme (GBM) commonly overexpresses the epidermal growth factor receptor (EGFR) gene and its ligand-independent mutant, EGFRvIII. Amplification of the EGFR gene has been implicated in the pathogenesis of primary GBM, in particular the small cell phenotype, and this finding may contribute to its aggressive clinical behavior. Anti-EGFR clinical trials for GBM are being conducted, and it would be useful to identify a rapid technique to determine whether EGFR expression and the small cell phenotype are associated with a response to therapy. In the present study we examined 56 cases of GBM using chromogenic in situ hybridization (CISH). CISH analysis and morphology identified 22 small cell (SCGBM) and 22 non-small cell glioblastoma (NSCGBM), and 12 cases of a mixed phenotype. Fourteen cases of SCGBM (14/22) showed EGFR amplification, while only 5 NSCGBM (5/22) cases showed amplification. We have therefore used CISH as an efficient, economic and reliable means for routinely assessing EGFR amplification in GBM, including the small cell variant.  相似文献   
32.
In infants, the tip of a cannula is sometimes used as introducer during peripherally inserted central catheters placement. We report a rare complication of this procedure, characterized by intravascular migration of the cannula tip during peripheral insertion of a central venous catheter. We review this unlikely complication and treatment options.  相似文献   
33.
Corticosteroids have long represented the drugs of choice for intra-articular treatment of osteoarthritis (OA), but their use has drawbacks, indicating the need for alternatives devoid of these effects. This comparative study examined the clinical efficacy and the structural effects of intra-articular injections of sodium hyaluronate (HA) of molecular weight (MW) 500–730 kDa (one injection weekly for 5 weeks) versus methylprednisolone acetate (MP) (one injection weekly for 3 weeks) in the treatment knee OA. We studied 99 patients with knee OA, primary or secondary to a traumatic event, classified according to criteria of the American College of Rheumatology. Pain assessments by VAS and arthroscopic examinations of synovial membrane and cartilage were performed at baseline and 180 days after the start of the treatment. Arthroscopic features were evaluated under blind conditions. Initially, MP showed a more immediate beneficial clinical effect in reducing pain than HA, but after 180 days the symptomatic effect of HA was more long lasting than that of MP. Arthroscopic findings at day 180, in comparison with baseline conditions, showed that both drugs were decreased synovial membrane inflammation but HA was superior to MP in reducing the grade and extent of cartilage damage. HA of 500–730 kDa represents a valid alternative to corticosteroids in the intra-articular treatment of OA with a beneficial effect on the structural alterations. This study supports previous data on a potential structure-modifying activity of HA in OA of the knee. Received: 10 May 2002, Accepted: 20 May 2002  相似文献   
34.
Colonic anastomoses made both by a new Compression Anastomotic Device (CAD) and by a traditional stapler (Autosuture CDEEA) were evaluated in impaired anastomotic healing induced by systemic cortisone in the dog. Twenty dogs were given daily i.m. hydrocortisone (25 mg/kg) starting one month before surgery and then until sacrifice. Eight untreated dogs served as controls. Surgery consisted of colonic transection and anastomosis done with CAD-25 in half the cases and with CDEEA-25 in the remaining half. The dogs were sacrificed six and 13 days after surgery. Macroscopic assessment, bursting pressure test, and histology were performed on the anastomosis. One dog died from peritonitis due to anastomotic dehiscence. No other clinical complications were observed. Although the number of observations was too small to attain statistical significance, CAD anastomoses appeared better than stapled ones as regards peri-anastomotic adhesions, anastomotic index, and histology. This preliminary study suggests that compression is as reliable as the stapler in the construction of colon anastomosis even in such situations of delayed anastomotic healing. Further experience is required to substantiate this conclusion.  相似文献   
35.
The development of cancer prevention strategies depends on the elucidation of molecular pathways underlying oncogenesis. In a previous proteomic study of matched normal breast ducts and Ductal Carcinoma in Situ (DCIS), we identified overexpression of Rab11a in DCIS. Rab11a is not well studied in cancer, but is known to regulate the recycling of internalized cell surface proteins and receptors from the early endosome through the trans-Golgi network. Using immunohistochemistry, we confirmed our observation, noting increased Rab11a expression in 19 of 22 (86%) DCIS cases compared to matched normal breast epithelium. To study the function of Rab11a, immortal, nontumorigenic MCF10A breast cells were stimulated with ligands to the EGF receptor (EGFR) after transfection with empty vector (control), Rab11a, or a S25N dominant-negative (DN) Rab11a. Using an iodinated ligand:receptor recycling assay, transfection of Rab11a accelerated, while DN-Rab11a postponed EGFR recycling in vitro. The signaling and in vitro phenotypic consequences of Rab11a expression and function were studied. Transfection of DN-Rab11a increased Erk1/2 activation downstream of EGF, but exerted no effect on the Akt pathway. Expression of DN-Rab11a inhibited MCF10A proliferation by 50–60%, and also inhibited anchorage-dependent colonization. Notably, DN-Rab11a transfection increased motility toward EGFR ligands. The data provide a first demonstration that Rab11a modulates EGFR recycling, and promotes the proliferation but inhibits the motility of an immortal breast line, consistent with the DCIS phenotype.Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   
36.
Elastin-proteoglycans association revealed by cytochemical methods   总被引:4,自引:0,他引:4  
By using various cytochemical stains, proteoglycans are shown to be present inside elastic fibers in aortas of beta-aminopropionitrile-induced lathyritic chicks. Depending on the characteristics of the dyes, the shape, size and distribution of the proteoglycan-revealing precipitates are described. The monocationic dye toluidine blue O and the tetracationic dye Alcian blue in the presence of 0.3 M MgCl2 give the most detailed results. With these stains the proteoglycans inside lathyritic elastin appear to be lateral branches of matrix proteoglycans, lying on the external surface of the elastic fibers. A possible general biological significance of elastin-proteoglycan association is briefly discussed.  相似文献   
37.
A high percentage of regulatory T cells (Tregs) among tumor-infiltrating lymphocytes weakens the immune response against tumors. The anergy of effector T cells (Teff) can be reversed by immune checkpoint treatment, which inhibits Tregs and boosts the activation of Teff. Both effects can be obtained by triggering the glucocorticoid-induced TNF receptor-related (GITR), a costimulatory molecule expressed by Teff and Tregs, and by inhibiting the programmed cell death (PD)-1 receptor, an inhibitory molecule expressed by Teff. Patent W02015026684A1 provides a method of treating human tumors using a combination of a molecule triggering GITR and another inhibiting PD-1. The treatment approach was tested on three murine models of cancer, and the synergic effect of antihuman antibodies (Abs) in combination was tested in mixed lymphocyte reactions. Immune checkpoint treatment can break tolerance toward tumors and promote tumor rejection. The patented approach is very interesting and might be successful. The combined use of PD-1 antagonists and GITR agonists is synergic and tumor-centered, and adverse events might be less problematic than expected. A crucial point in translating the murine studies to humans is the differences between murine and human GITR and the evidence that some antihuman GITR Abs are not agonists.  相似文献   
38.
The aim of the present study was to compare cellular and noncellular components of bronchoalveolar lavage fluid (BAL) in a group of children with a diagnosis of chronic diffuse parenchymal lung disease (cDPLD) and a group of children without parenchymal lung disease undergoing BAL for various clinical indications (control group). We evaluated cellular and non-cellular components (total proteins, albumin, hyaluronic acid, and fibronectin) in BAL fluid from 14 children (7 boys and 7 girls; mean age 9.2 years, range 5 months to 18.4 years) fulfilling the clinical and radiological diagnosis of chronic cDPLD, and in 19 controls without evidence of lung disease. The 14 patients were assigned to two study groups: early-stage cDPLD (6 patients; age range 5 months to 5.2 years; duration of illness, 5-7 months) and long-standing cDPLD (8 patients; age range 9.6-18.4 years; duration of illness, 1.2-17.6 years). Ninety-three percent of the patients with cDPLD had at least two BAL constituents outside normal limits, with high numbers of cells, including all types of alveolar cells, but especially lymphocytes and foamy macrophages. These findings indicate a mixed, predominantly lymphocytic alveolitis. Our patients also had a significant increase in two noncellular BAL components, namely fibronectin and hyaluronic acid. BAL samples from children with long-standing cDPLD contained increased numbers of lymphocytes, whereas samples from children with early-stage cDPLD contained increased percentages and numbers of foamy macrophages and increased concentrations of fibronectin, hyaluronic acid, and albumin. In conclusion, we clearly identified an abnormal BAL profile in our group of cDPLD patients. Moreover, BAL findings differentiated younger cDPLD patients in the early stages of their illness from old patients with long-standing disease.  相似文献   
39.
A case characterized by a rare synchronous occurrence of transitional cell carcinoma of the renal pelvis and renal cell carcinoma in the contralateral kidney is presented. The simultaneous occurrence of renal adenocarcinoma and transitional cell carcinoma of the renal pelvis in the opposite kidney is unusual.  相似文献   
40.
A 4-month-old baby girl, after a period of apparent good health, began to have aphonia, dyspnea, difficulties with swallowing, cyanosis, apnea, and hypopnea during sleep that resulted in admission to an intensive care unit for intubation and mechanical ventilation. At the age of 9 months she was admitted to our hospital with a possible diagnosis of central hypoventilation syndrome. A polysomnographic study showed apnea and hypopnea (apnea + hypopnea index = 47.1), hypercapnia (mean end-tidal P 89 ± 15.0 mmHg), and arterial desaturation (mean Sa 91 ± 1.7%; lowest Sa < 50%; 68% of total sleep time at Sa below 93%); the study also showed an absent ventilatory response to CO2, absent cardiac responses to apnea during sleep, and right ventricular hypertrophy. Nocturnal nasal bi-level positive airway pressure (BiPAP), applied initially at 6 cmH2O and gradually increased to 16 cmH2O, caused the sleep-related abnormal respiratory events to disappear. End-tidal Pco2 decreased to 39 mmHg, and Sao2 increased to 94%. After 6 months of nocturnal BiPAP ventricular right hypertrophy reversed and arrested growth and hypotonia normalized. The child has tolerated and has remained on BiPAP support up to her current age of 3 years and continues to use this form of ventilatory assistance without difficulties. Pediatr. Pulmonol. 1997;24:66–69. © 1997 Wiley-Liss, Inc.  相似文献   
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