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101.
Gastrointestinal stromal tumors are rare neoplasms arising from mesenchymal precursor cells of the gastrointestinal tract that may differentiate towards the interstitial cells of Cajal, pacemaker cells regulating autonomous motility of G.I. tract. Grading of GIST has been proven to be as difficult as their classification. Two thirds of GISTs are located in the stomach, 20-50% in the small bowel (one third in the duodenum), and 5-15% in colon and rectum; GISTs, however, may rarely be found also in the oesophagus, omentum, mesentery or the retroperitoneum. The distribuition of these tumors in the stomach is: pars media, 40%; antrum, 25%; pylorus, 20%; in less than 15%, GISTs location is next to the EGJ, in the cardia and in the iundus. The upper gastric third location of GISTs is not common, so their surgical management has been not yet well investigated. Total gastrectomy is considered the therapy of choice for the GIST located next to the EGJ, but wedge resection could be considered a surgical option in selected cases. The Authors describe 2 cases of GIST located just under the upper portion of the stomach and discuss about the different surgical options for GISTs of this region.  相似文献   
102.
BACKGROUND: This study assessed the endovascular embolization of splenic artery aneurysms and false aneurysms with special consideration given to postoperative complications. METHODS: Fifteen patients (11 women; mean age, 56 y; range, 39-80 y) with splenic artery aneurysm (n = 13) or false aneurysm (n = 2) were treated with coil embolization. The lesion was asymptomatic in 9 patients, symptomatic in 5 patients, and ruptured in 1 patient. The mean aneurysm diameter was 33 +/- 23 mm (range, 15-80 mm). Postoperative follow-up evaluation included a clinical visit and spiral computed tomography at 1, 4, and 12 months, and yearly thereafter. RESULTS: Endovascular treatment was possible in 14 patients (93%) (1 failure: neck cannulation). Perioperative mortality was not observed. Morbidity included postembolization syndrome in 5 patients (30%). Neither pancreatitis nor spleen abscess occurred. The mean follow-up period was 36 months (range, 3-60 mo). During follow-up evaluation we detected 1 sac reperfusion that was sealed successfully with additional coils. Surgical conversion or open repair were never required. CONCLUSIONS: At our institute, endovascular treatment represents the first-line treatment for splenic artery aneurysms. Postembolization syndrome and infarcts are common events but generally resolve without sequelae.  相似文献   
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In bicuspid aortic valve (BAV) disease, the role of genetic and hemodynamic factors influencing ascending aortic pathology is controversial. To test the effect of BAV geometry on ascending aortic flow, a finite element analysis was undertaken. A surface model of aortic root and ascending aorta was obtained from magnetic resonance images of patients with BAV and tricuspid aortic valve using segmentation facilities of the image processing code Vascular Modeling Toolkit (developed at the Mario Negri Institute). Analytical models of bicuspid (antero‐posterior [AP], type 1 and latero‐lateral, type 2 commissures) and tricuspid orifices were mathematically defined and turned into a volumetric mesh of linear tetrahedra for computational fluid dynamics simulations. Numerical simulations were performed with the finite element code LifeV. Flow velocity fields were assessed for four levels: aortic annulus, sinus of Valsalva, sinotubular junction, and ascending aorta. Comparison of finite element analysis of bicuspid and tricuspid aortic valve showed different blood flow velocity pattern. Flow in bicuspid configurations showed asymmetrical distribution of velocity field toward the convexity of mid‐ascending aorta returning symmetrical in distal ascending aorta. On the contrary, tricuspid flow was symmetrical in each aortic segment. Comparing type 1 BAV with type 2 BAV, more pronounced recirculation zones were noticed in the latter. Finally, we found that in both BAV configurations, maximum wall shear stress is highly localized at the convex portion of the mid‐ascending aorta level. Comparison between models showed asymmetrical and higher flow velocity in bicuspid models, in particular in the AP configuration. Asymmetry was more pronounced at the aortic level known to be more exposed to aneurysm formation in bicuspid patients. This supports the hypothesis that hemodynamic factors may contribute to ascending aortic pathology in this subset of patients.  相似文献   
106.
Left ventricular hypertrophy (LVH) is a strong cardiovascular risk marker in end‐stage renal disease (ESRD) patients. Vitamin D deficiency and/or disturbed vitamin D signaling has been implicated in LVH in experimental models. Because the BsmI vitamin D receptor VDR gene polymorphism may alter VDR function, we performed a cross‐sectional and longitudinal study in a cohort of 182 dialysis patients to investigate (1) the relationship between BsmI VDR gene polymorphism and left ventricular mass index (LVMI) measured by echocardiography and (2) the predictive power of this polymorphism for progression in LVH over a 18 ± 2 months of follow‐up. As a reference group, we used 175 healthy subjects matched to the study population as for age and sex. The distribution of BsmI genotypes did not significantly deviate from Hardy‐Weinberg equilibrium either in patients or in the control group of healthy subjects. The frequency of the B allele of BsmI polymorphism (40.4%) in dialysis patients was similar to that of healthy control subjects (38.6%), and the number of B alleles was directly related to LVMI (r = 0.20, P = .007). This relationship remained robust (β = 0.19, P = .006) in multivariate analysis adjusting for traditional and nontraditional risk factors and antihypertensive and calcitriol treatment. In the longitudinal study, LVMI rose from 60.1 ± 17.9 to 64.2 ± 19.3 g/m2.7 (P < .001), and again, the number of B alleles was associated with LVMI changes both in crude and in fully adjusted analyses. These cross‐sectional and longitudinal observations coherently support the hypothesis that altered vitamin D signaling is implicated in LVH in ESRD patients. © 2010 American Society for Bone and Mineral Research  相似文献   
107.
The incidence of invasive fungal infection is increasing especially in the field of transplantation, affecting as many as 50% of bone marrow transplant (BMT) patients with neutropenia and 5-20% of solid-organ transplant (SOT) recipients. Fusarium species are soil saprophytes and plant pathogens. They may cause superficial mycoses or important opportunistic infections in patients with bone marrow suppression and neutropenia, they have been rarely described in solid organ recipients, and up to now there have been no reports of such infection in isolated liver transplanted patients. We describe a case of disseminated Fusarium solani infection with hepatic localization in a liver transplanted patient that resolved with the administration of amphotericin B. Our observation confirms that Fusarium spp. are emerging pathogens that may most frequently affect not only BMT patients and patients with hematological malignancies, but also SOT patients. They may cause both localized and disseminated infection. In conclusion, Fusarium spp. etiology should be considered in the context of infectious diseases following liver transplantation.  相似文献   
108.

Background

Bicalutamide monotherapy is a valuable option for prostate cancer (PCa) patients who wish to avoid the consequences of androgen deprivation; however, this treatment induces gynaecomastia and mastalgia in most patients. Tamoxifen is safe and effective in preventing breast events induced by bicalutamide monotherapy without affecting antitumor activity, but possible interference between bicalutamide and tamoxifen remains a matter of concern. To reduce the exposure to tamoxifen, we considered the putative advantages of weekly administration.

Objective

To compare the efficacy of two different schedules of tamoxifen in preventing breast events. Toxicity, prostate-specific antigen behaviour, and sexual-functioning scores were also evaluated.

Design, setting, and participants

This was a noninferiority trial. From December 2003 to February 2006, 80 patients with localised/locally advanced or biochemically recurrent PCa who were also candidates for bicalutamide single therapy were randomised to receive two different schedules of tamoxifen: daily (n = 41) and weekly (n = 39). Median follow-up was 24.2 mo.

Intervention

Daily bicalutamide (150 mg) plus daily tamoxifen 20 mg continuously (daily group) or the same but with tamoxifen at 20 mg weekly after the first 8 wk of daily treatment (weekly group). Three patients in the weekly group and one in the daily group were discontinued for adverse events.

Measurements

For gynaecomastia, we used ultrasonography. For mastalgia and sexual functioning, we used questionnaires.

Results and limitations

Gynaecomastia developed in 31.7% of patients in the daily group and in 74.4% of patients in the weekly group (p < 0.0001), and it was more severe in patients who switched to weekly tamoxifen (p = 0.001). Mastalgia occurred in 12.2% and 46.1% of patients, respectively (p = 0.001). There were no major differences among treatment schedules relative to sexual functioning scores and incidence and severity of adverse events. No differences between groups in PSA behaviour and disease progression have been detected so far.

Conclusions

This study demonstrated that tamoxifen 20 mg/wk is inferior to tamoxifen 20 mg/d in preventing the incidence and severity of bicalutamide-induced breast events. The safety and efficacy of tamoxifen at the common daily dose of 20 mg for the prophylaxis of bicalutamide-induced breast events were confirmed.  相似文献   
109.
Few molecular prognostic and predictive biomarkers have been identified so far in genitourinary tumors. We started from a literature search to explore the status of the art of molecular pathology tests as diagnostic, prognostic, predictive biomarkers in genitourinary cancers. Next generation sequencing approaches now provide mind-changing information in the fields of kidney cancer diagnosis, predictive oncology of urothelial cancer, understanding the causes of testicular and penile cancer, and the comprehension of the drivers of prostate cancer progression beyond androgen regulation. The classification of kidney cancer will be based soon on molecular changes. The causes of non-HPV related penile cancer are largely unknown. The emerging high incidence of testicular cancer could be explained only on the basis of molecular changes. The response to novel therapeutic agents in prostatic and urothelial cancer will require thorough molecular tumor characterization. The hereditary risk of patients with early onset prostate cancer and their potential treatment with targeted therapy requires germline and somatic genetic assays. The implementation of effective biomarkers for the response to immune check-point inhibitors in genitourinary cancer is based on the assessment of inflammatory expression profiles and the tumor mutational burden. This review deals with the current tests and provides a tentative foresee of the future molecular biomarkers of genitourinary cancer.  相似文献   
110.
Aim: To study the immune-modulating and anti-oxidant effects of beta-glucan, papaya, lactoferrin, and vitamins C and E on sperm characteristics of patients with asthenoteratozoospermia associated with leucocytosis. Methods: Fifty-one patients referred to our Sterility Center for semen analysis were selected. Sperm parameters were assessed before and after patient's treatment with beta-glucan, lactoferrin, papaya, and vitamins C and E. DNA damage was assessed by the acridine orange test and sperm structural characteristics were evaluated by transmission electron microscopy. Results: After 90 days of treatment, an increase in the percentage of morphologically normal sperm (17.0 ± 5.2 vs. 29.8 ± 6.5) and total progressive motility (19.0± 7.8 vs. 34.8 ± 6.8) were detected. Structural sperm characteristics as well as chromatin integrity were also improved after treatment. In terms of leukocyte concentration in seminal fluid, a significant reduction was recorded (2.2 ± 0.9 vs. 0.9± 0.2). Conclusion: The treatment of an inflammatory process by the synergic action of immune modulators and anti-oxidants could protect sperm during maturation and migration, leading to improved sperm function. (Asian JAndrol 2008 Mar;. 10: 201-206)  相似文献   
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