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21.

BACKGROUND

Malignant fibrous histiocytoma, a subtype of primary lung sarcoma is a very rare disease. It usually presents as a lung nodules and the final diagnosis is made by immunohistochemical studies.

METHODS

A 45-year-old patient presented with progressive dyspnea, dry cough and right shoulder pain. Chest X-ray revealed complete opacification of the right hemithorax. Chest computed tomography confirmed the presence of a heterogeneous lesion occupying the whole right hemithorax causing a mass effect on the trachea. Ultrasound guided biopsy was done and final pathology was suggestive of malignant fibrous histiocytoma.

CONCLUSION

Progressive dyspnea in young otherwise healthy patients should be investigated early on. In our case the presence of right shoulder pain indicates advance disease illustrated by the singular imaging findings.  相似文献   
22.
Right ventricular (RV) function immediately after left ventricular assist device (LVAD) implantation is a crucial prognostic factor. RV failure is linked to increased mortality and worse outcome. A phosphodiesterase 5 inhibitor, sildenafil, was shown to decrease pulmonary vascular resistance and pulmonary artery pressure post‐LVAD. We report on a series of heart failure patients, and the effect of sildenafil on the incidence of RV failure after LVAD implantation. We retrospectively analyzed the data of end‐stage heart failure patients who underwent LVAD implantation with pulmonary hypertension and RV dysfunction prior to surgery. Patients were divided into two groups; group 1: patients who received sildenafil perioperatively, and group 2: patients who did not receive sildenafil. Hemodynamic and echographic data were collected before and after surgery. Fourteen patients were included, 8 patients in group 1 and 6 in group 2. Sildenafil was administered with a mean dose of 56.2 ± 9.4 mg in group 1 and was able to significantly reduce right heart failure incidence, and to demonstrate a significant reduction in pulmonary vascular resistance, pulmonary artery pressure, transpulmonary gradient, and a significant increase in cardiac output. In conclusion, sildenafil seems to have a promising role perioperatively in preventing acute RV failure postsurgery in patients with RV dysfunction and pulmonary hypertension, requiring LVAD therapy.  相似文献   
23.
24.
Dysregulated transforming growth factor beta (TGF‐β) signaling is associated with a spectrum of osseous defects as seen in Loeys‐Dietz syndrome, Marfan syndrome, and Camurati‐Engelmann disease. Intriguingly, neurofibromatosis type 1 (NF1) patients exhibit many of these characteristic skeletal features, including kyphoscoliosis, osteoporosis, tibial dysplasia, and pseudarthrosis; however, the molecular mechanisms mediating these phenotypes remain unclear. Here, we provide genetic and pharmacologic evidence that hyperactive TGF‐β1 signaling pivotally underpins osseous defects in Nf1flox/?;Col2.3Cre mice, a model which closely recapitulates the skeletal abnormalities found in the human disease. Compared to controls, we show that serum TGF‐β1 levels are fivefold to sixfold increased both in Nf1flox/?;Col2.3Cre mice and in a cohort of NF1 patients. Nf1‐deficient osteoblasts, the principal source of TGF‐β1 in bone, overexpress TGF‐β1 in a gene dosage–dependent fashion. Moreover, Nf1‐deficient osteoblasts and osteoclasts are hyperresponsive to TGF‐β1 stimulation, potentiating osteoclast bone resorptive activity while inhibiting osteoblast differentiation. These cellular phenotypes are further accompanied by p21‐Ras–dependent hyperactivation of the canonical TGF‐β1–Smad pathway. Reexpression of the human, full‐length neurofibromin guanosine triphosphatase (GTPase)‐activating protein (GAP)‐related domain (NF1 GRD) in primary Nf1‐deficient osteoblast progenitors, attenuated TGF‐β1 expression levels and reduced Smad phosphorylation in response to TGF‐β1 stimulation. As an in vivo proof of principle, we demonstrate that administration of the TGF‐β receptor 1 (TβRI) kinase inhibitor, SD‐208, can rescue bone mass deficits and prevent tibial fracture nonunion in Nf1flox/?;Col2.3Cre mice. In sum, these data demonstrate a pivotal role for hyperactive TGF‐β1 signaling in the pathogenesis of NF1‐associated osteoporosis and pseudarthrosis, thus implicating the TGF‐β signaling pathway as a potential therapeutic target in the treatment of NF1 osseous defects that are refractory to current therapies. © 2013 American Society for Bone and Mineral Research.  相似文献   
25.
We report a rare case of a secondary aortoesophageal fistula discovered incidentally during elective upper endoscopy. The patient had previously undergone repair of a descending thoracic aortic aneurysm with a Dacron interposition graft. Esophagoscopy 2 months after the aneurysm repair demonstrated a large mid-esophageal erosion with visualization of the aortic graft at the base. The aortoesophageal fistula had been clinically silent to this point. During preparation for surgery the patient developed large-volume esophageal hemorrhage and died following attempted endovascular repair of the fistula. A review of the literature on the diagnosis and surgical management of aortoesophageal fistula is presented.Presented at the 30th Annual Meeting of the Military Society for Vascular Surgery, Bethesda, MD, December 5, 2002.  相似文献   
26.
IntroductionGeriatric Nutritional Risk Index (GNRI) is a simple and quantitative method (based on three objective measurements: weight, height, albumin) for screening patients at risk for malnutrition. However no data are available regarding its relation with mortality in Caucasian hemodialysis patients. We tested the predictive value of GNRI on mortality in a hemodialysis population followed up prospectively for 18 months.MethodsA total of 46 stable prevalent (mean age: 76 ± 11 years, range: 42–95) hemodialysis patients from one center were included in the study. GNRI with other nutritional parameters were evaluated for all patients.ResultsSixteen patients (35%) died during the 18 months of follow-up. Multiple logistic model showed that GNRI and Charlson co-morbidity score were significant predictors of mortality. Age and gender were not significant.ConclusionOur preliminary study carried out on a series of prevalent hemodialysis patients suggests that GNRI is predictor of mortality. To recommend the use of this index for the screening of hemodialysis patients with malnutrition at risk of mortality, our results should be confirmed by a large cohort study.  相似文献   
27.
We report our experience and the midterm results of a modern technique for endovascular management of isolated iliac artery aneurysms (IAAs) with unfavorable neck anatomy, which involves the inversion of an iliac leg of a Zenith stent graft. Patients who underwent endovascular IAA repair from 2002 to 2010 were reviewed. A total of 12 patients, with a mean age of 77.6 years, underwent endovascular repair of 13 IAAs. Mean size of the aneurysms was 54.6 mm (range 34-133 mm). Mean proximal neck diameter was 18 mm (range 15-22 mm). In 7 patients, the length of the proximal neck was <15 mm (10-14 mm). Only 1 patient developed thrombosis of the stent graft immediately after the operation. Patients were followed up for a mean of 31.5 months (range 18-72 months). Our midterm results demonstrate the durability of this technique in the management of iliac aneurysms with unfavorable anatomy.  相似文献   
28.

Introduction

Testicular seminoma affects relatively young men with excellent survival outcomes. There has been increasing concern that radiotherapy (RT) leads to secondary malignant neoplasms (SMNs) and subsequent mortality. We evaluated the effect of RT on incidence of SMNs and quantified cancer-related mortality and other causes of death for patients with stage I and II testicular seminoma.

Material and methods

A national sample of men (1988–2013) diagnosed with stage IA/IB/IS/IIA/IIB/IIC testicular seminomas from Surveillance, Epidemiology, and End Results were evaluated. Use of RT over time and survival curves (5/10/15-year) was stratified by stage. Log-binomial regression determined relative risk of developing SMNs. Incidence rate ratios (IRR) and age-adjusted Cox proportional hazards models compared overall, cancer-specific survival (CSS), and other cancer-specific survival. Competing-risks regression generated cumulative incidence functions. Prevalence ratios explored excess deaths owing to specific causes.

Results

A total of 16,463 men were included with 9,126 (55.4%) undergoing RT with markedly decreased use for stage I seminoma in recent years (<20%) and ~50% for stage IIA. RT increased risk of SMNs (relative risk = 1.84 [95% CI: 1.61–2.10, P<0.01]). Survival rates were excellent (15-year CSS for stage I [≥99%], stage IIA [98.1%], stage IIB-C [96%–97%]). RT was associated with improved CSS for stage IB and IIA, but demonstrated less benefit for stage IA (IRR = 0.63 [95% CI: 0.35–1.14, P = 0.10]) with worse other cancer-specific survival (IRR = 1.80 [95% CI: 0.97–3.59, P = 0.05]). Gastrointestinal, respiratory, urinary, and hematologic malignances accounted for 84% of SMN deaths.

Conclusions

RT offers excellent CSS for men with stage I/II seminoma and an increased risk of SMN later in life. Future studies should better evaluate risk-stratification for stage IB patients.  相似文献   
29.
High-energy tibial plateau fractures associated with severe soft tissue injury are difficult to manage. The risk of wound complications following open reduction and internal fixation is notably high owing to extensive soft tissue dissection. Alternatively, application of hybrid external fixator minimizes soft tissue dissection and provides adequate fracture stabilization to allow early range of motion and correction of any mal-alignment. With this technique, soft tissue complications particularly surgical site infections are expected to be significantly reduced. This prospective study aims to determine the effectiveness of a modified hybrid external fixator in the management of high-energy tibial plateau fractures. Thirty-three patients with high-energy Schatzker V and VI tibial plateau fracture with severe soft tissue injury precluding formal open reduction were enrolled into the study. The fixator was a construct combining the Ilizarov ring with a monolateral external fixator. The results—bony union, range of motion, and associated complications of the treatment—were assessed. All fractures united within an average time of 14 weeks. Neither loss of reduction nor surgical site wound breakdown/osteomyelitis was noted. Eight patients developed superficial pin track infection and one septic arthritis of the knee joint. Hybrid external fixation is a safe option for complex high-energy tibial plateau fractures by simultaneously providing adequate fracture stabilization and protection of soft tissue healing to achieve bony union. The complication is mainly related to pin tract infection.  相似文献   
30.
A case of negative pressure bilateral pulmonary edema in a 28 years old healthy female patient, scheduled for diagnostic pelvic laparoscopy for infertility. Following extubation and apparent recovery from anesthesia, she had strong inspiratory efforts due to airway obstruction caused by coughing and laryngeal spasm, that lead to negative pressure bilateral pulmonary edema. The pulmonary edema disappeared within few hours. She was breathing spontaneously through CPAP system (mask-bag-expiratory valve). Diuretics and lungs physiotherapy helped in controlling patient's complication.  相似文献   
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