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81.
Background The aim of this study was to search for mutations in the humanmutS homolog 2 (hMSH2) and humanmutL homolog 1 (hMLH1) genes in 25 unrelated Brazilian kindreds with suspected hereditary nonpolyposis colorectal cancer (HNPCC). Methods The families were grouped according to the following clinical criteria: Amsterdam I or II; familial colorectal cancer (CRC); an early age of onset of CRC in the proband only; or with at least one or two relatives who had HNPCC-related cancers; CRC in the proband only. All patients were studied with direct sequencing. Results Ten mutations were detected (10 of 25 [40%]); of nine different mutations, seven were novel. ThehMLH1 gene had a higher mutation detection rate thanhMSH2 (8 of 25 [32%] vs. 2 of 25 [8%]). Only 3 of these 10 families fulfilled the Amsterdam criteria. Two different polymorphisms were detected in thehMLH1 gene and four in thehMSH2 gene. Conclusions ThehMLH1 gene had a higher mutation detection rate thanhMSH2. The physician who deals with CRC must take into consideration the heredity issue with patients who present with an early age of onset or a familial history of CRC- or HNPCC-related cancers, including gastric cancer, even if they do not fulfill the former Amsterdam criteria.  相似文献   
82.
Mesenchymal stem cells (MSCs) from bone marrow (BM) and sub-cutaneous fat are known to differentiate into neural cells under appropriate stimuli. We describe here the neural-like differentiation of human MSCs obtained from spleen and thymus, induced either with chemical factors or with co-culture with human Schwann cells (Sc). Under the effect of neural differentiation medium, most MSCs from BM, fat, spleen and thymus acquired morphological changes suggestive of cells of astrocytic/neuronal and oligodendroglial lineages with general up-regulation of neural molecules not correlated with morphological changes. The process was transient and reversible, as MSCs recovered basal morphology and phenotype, as well as their multilineage differentiation potential. Thus, we hypothesized that chemical factors may prime MSCs for neural differentiation, by inducing initial and poorly specific changes. By contrast, co-cultures of MSCs of different origin with Sc induced long-lasting and Sc differentiation, i.e., the expression of Sc myelin proteins for up to 12 days. Our results show that a MSC reservoir is present in tissues other than BM and fat, and that MSCs of different origin have similar neural differentiation potential. This evidence provides new insights into BM-like tissue plasticity and may have important implications for future therapeutic interventions in chronic neuropathies.  相似文献   
83.
The endogenous cannabinoid system is involved in the regulation of a number of physiologic effects in both the central and peripheral nervous systems. Its role in the control of neuronal cell proliferation has attracted major attention because of its potential implications for new therapeutic strategies. In the present study, we demonstrated that treatment of cultured cerebellar granule cells with the synthetic cannabinoid WIN55,212-2, causes cell-body and nuclear shrinkage, which are hallmarks of neuronal apoptosis, as well as concentration-dependent decrease in cell viability. Staining with the fluorescent nuclear dye, Hoechst 33258, revealed apoptosis in 27.1% and 58.5% of cells exposed to 1 and 10 microM of WIN55,212-2, respectively (P < 0.01 and P < 0.001 vs. control respectively) after 36 hr. After 24 hr of exposure to WIN55,212-2, mRNA levels for the anti-apoptotic gene bcl-xL were reduced to 45.6% of those found in control (P < 0.01). These effects were completely reverted when cells were exposed to the synthetic cannabinoid in the presence of the specific CB1-receptor antagonist, SR141716A (1 microM). Moreover, the pro-apoptotic effect of 10 microM WIN55,212-2 could be reduced by the addition to the incubation medium of a cell-permeant inhibitor of caspase-1 (50 nM). Finally, WIN55,212-2 significantly increased caspase-1 activity after 24 hr. These findings show that the activation of CB1 receptors on cerebellar granule cells induces apoptotic cell death, which is associated with downregulation of the anti-apoptotic gene, bcl-xL, and at least in part, activation of caspase-1.  相似文献   
84.
85.
Study Type – Diagnosis (RCT) Level of Evidence 1b What’s known on the subject? and What does the study add? Transrectal gray‐scale ultrasonography guided prostate biopsy sampling is the method for diagnosing prostate cancer (PC) in patients with an increased prostate specific antigen level and/or abnormal digital rectal examination. Several imaging strategies have been proposed to optimize the diagnostic value of biopsy sampling, although at the first biopsy nearly 10–30% of PC still remains undiagnosed. This study compares the PC detection rate when employing Colour Doppler ultransongraphy with or without the injection of SonoVueTM microbubble contrast agent, versus the transrectal ultrasongraphy‐guided systematic biopsy sampling. The limited accuracy, sensitivity, specificity and the additional cost of using the contrast agent do not justify its routine application in PC detection.

OBJECTIVE

? To compare prostate cancer (PC) detection rate employing colour Doppler ultrasonography with or without SonoVueTM contrast agent with transrectal ultrasonography‐guided systematic biopsy sampling.

PATIENTS AND METHODS

? A total of 300 patients with negative digital rectal examination and transrectal grey‐scale ultrasonography, with PSA values ranging between 2.5 and 9.9 ng/mL, were randomized into three groups: 100 patients (group A) underwent transrectal ultrasonography‐guided systematic bioptic sampling; 100 patients (group B) underwent colour Doppler ultrasonography, and 100 patients (group C) underwent colour Doppler ultrasonography before and during the injection of SonoVueTM. ? Contrast‐enhanced targeted biopsies were sampled into hypervascularized areas of peripheral, transitional, apical or anterior prostate zones. ? All the patients included in Groups B and C underwent a further 13 systematic prostate biopsies. The cancer detection rate was calculated for each group.

RESULTS

? In 88 (29.3%) patients a histological diagnosis of PC was made, whereas 22 (7.4%) patients were diagnosed with high‐grade prostatic intraepithelial neoplasia or atypical small acinar proliferation. ? No significant differences were found among the three groups for cancer detection rate (P= 0.329). ? Additionally, low sensitivity, specificity and accuracy of colour Doppler with or without SonoVueTM contrast agent were found.

CONCLUSIONS

? Prostate cancer detection rate does not significantly improve with the use of colour Doppler ultrasonography with or without SonoVueTM. ? Although no collateral effects have been highlighted, the combined use of colour Doppler ultrasonography and SonoVueTM determines adjunctive costs and increases the mean time for taking a single prostate biopsy.  相似文献   
86.
BACKGROUND: Different techniques have been proposed to measure the correct length of artificial chordae. We herein describe a new simple method to measure the chordal length in complex chordal replacement. METHOD: Chordal replacement was used by us for two different purposes: (1) to maintain the correct chordal length for the anterior leaflet (AL) and (2) to eliminate any movement of the posterior leaflet (PL) to fix it. To reach this goal, the AL is pulled up to the maximum extent and the new chordae are tied 5 mm higher than the related border. On the contrary, in the PL the new chordae are tied at the level of the related border. RESULTS: From March 2006 to March 2007, at the University of Catania, this technique was used in 32 patients (16 for correction of PL prolapse, 6 patients for correction of AL prolapse, and in 10 patients for correction of both leaflets prolapse). The number of chordae per patients was 8.6 for the PL and 6.8 for the AL. No patient died or had major complications. After a mean follow-up of 5 +/- 2 months, two-dimensional echocardiography showed that all the patients had no or trivial mitral regurgitation (MR). The echocardiogram showed a correct movement of the new chordae. CONCLUSIONS: This technique allows to easily establish the length of the new chordae of the AL and, if necessary, of the PL in complex mitral valve repair.  相似文献   
87.
88.
Background ACTH-independent macronodular adrenal hyperplasia (AIMAH) is a rare cause of Cushing’s syndrome. Bilateral adrenalectomy is considered the treatment of choice, with subsequent lifetime steroid replacement, but unilateral adrenalectomy has been recently proposed to reduce the secreting tissue. This prospective study was designed to evaluate the long-term results of unilateral adrenalectomy in AIMAH concerning the main laboratory and clinical abnormalities and the patient’s quality of life. Methods Seven consecutive patients with confirmed AIMAH underwent unilateral adrenalectomy of the largest gland. ACTH and cortisol levels, arterial blood pressure (BP), glycometabolic parameters, and patient’s subjective perception of health-related quality of life (by the SF-36 questionnaire) were measured preoperatively and postoperatively. Results No surgery-related morbidity occurred. One patient with a large contralateral adrenal enlargement required a completion adrenalectomy after 7 months because of persistent hypercortisolism. At a median follow-up of 53 (range, 27–68) months, the remaining six patients were cured, because serum and urinary free cortisol levels significantly decreased and ACTH increased, thus regaining the normal range. Both systolic and diastolic BP levels significantly reduced: 50% of patients definitively became normotensive, and the remaining patients reduced the need for antihypertensive treatment; 40% of patients suffering from preoperative diabetes were cured, whereas 40% reduced the need for hypoglycemizing drug. SF-36 evaluation of the health-related quality of life confirmed a significant amelioration. Conclusions Unilateral adrenalectomy of the largest gland can be an effective and safe treatment for AIMAH in case of asymmetric involvement. It may achieve long-term remission of Cushing’s syndrome and improve BP values, glycemic control, and patient’s quality of life.  相似文献   
89.
This study was aimed at identifying predictive variables for recurrence of mitral regurgitation (MR) in patients with dilated cardiomyopathy (DCM) undergoing mitral valve (MV) repair. From January 1997 to December 2005, 142 patients with DCM, 105 (73.9%) ischemic and 37 (26.1%) non-ischemic, underwent MV repair. Mean age was 66+/-10 years and mean MR grade was 3.2+/-0.7 (scale 1+ to 4+). Ninety-seven (71% ischemic, 29% non-ischemic), out of 98 still alive at follow-up, were included in this retrospective analysis. In all cases MV posterior annuloplasty was performed; all patients were followed-up by echocardiography (mean time interval of 44+/-28 months) to evaluate MR recurrence (>or=2+/4+). Thirty-day mortality was 9.2% (13 patients). Mean MR grade at follow-up was 0.9+/-0.9. Four-year freedom from MR recurrence was 65.5%+/-8.3. Cox analysis showed left ventricular end-diastolic volume index (LVEDVi, OR=1.03, P=0.016, AUC=0.72), left ventricular end-systolic volume index (LVESVi, OR=1.03, P=0.033, AUC=0.71), left ventricular ejection fraction (LVEF, OR=0.82, P=0.001, AUC=0.72), mitral valve coaptation depth (MVCD, OR=1.6, P=0.017, AUC=0.72) to be predictive variables for MR recurrence. Preoperative left ventricular dilatation and function along with degree of papillary muscle displacement can be helpful in identifying patients with higher probability to undergo a durable MV repair.  相似文献   
90.
OBJECTIVE: To evaluate the peri-operative results of Anaconda endograft in the first 49 cases treated in a single centre. METHODS: The study was carried out prospectively on cases of infrarenal abdominal aortic aneurysm (AAA) treated with Anaconda endograft. The characteristics of the proximal aortic neck and of the iliac access vessels were considered. The following operative results were assessed: the main body oversizing, the need to correct the positioning of the main body, the use of iliac extensions, the use of ballooning, the covering of patent hypogastric arteries, the presence of endoleaks and the need for conversion. Peri-operative (30 days) mortality and morbidity were also considered. RESULTS: Of the 49 cases treated, 44 were males with a mean age of 73 years (range: 55-89 yrs; SD+/-7 yrs). The mean diameter of the AAA was 56 mm (range 45-91 mm; SD+/-11); 4 cases had common iliac aneurysms with a diameter >3 cm. The mean neck diameter and length were 23 mm (range 19-28 mm; SD+/-3) and 25 mm (range 15-50 mm; SD+/-10) respectively. An aortic neck angle between 40 degrees and 70 degrees was present in 10 cases (20%) (mean 58 degrees; SD+/-15 degrees), and 20 cases (41%) had iliac tortuosity with an angle greater than 60 degrees (mean 85 degrees; SD+/-25 degrees). There were no cases of conversion or intra-operative death. One (2%) peri-operative death occurred, for reasons not related to the endograft. There were two cases of iliac limb thrombosis. CT at one month showed 12 cases (25%) of type II endoleak. There were no cases of type I or type III endoleaks. CONCLUSIONS: The preliminary data of this series demonstrates that the Anaconda endograft has good peri-operative results in the treatment of infrarenal AAAs with a neck length not less than 15 mm.  相似文献   
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