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91.
We analyzed the postoperative short- and mid-term outcomes of a series of patients with annuloaortic ectasia who underwent a modified Bentall operation in our clinic from September 2000 through March 2006. The study included 44 patients. Their average age was 53.4 +/- 14.1 years. The underlying disease was degenerative aortic aneurysm in 42 patients (95.5%) and acute aortic dissection in 2 patients (4.5%). Six patients (13.6%) had Marfan phenotype. Aortic insufficiency was moderate in 30 patients (68.2%) and severe in 14 patients (31.8%). In our modification of the Bentall technique, we completed the resection of the aortic root while leaving 5 to 10 mm of native aortic wall tissue to support the anastomosis. A long piece of Teflon felt (width, 0.5-1 cm) was laid on the annulus, and nonpledgeted 2-0 polyester sutures were passed in turn through the Teflon felt, the preserved aortic tissue, and the aortic annulus. A thin piece of Teflon felt was also used in the coronary artery reimplantation sites. Fibrin glue was routinely applied to all anastomoses. There were no intraoperative deaths. One patient died in the hospital after surgery for acute type I aortic dissection. Another patient died 1 year after the operation from prosthetic-valve endocarditis. No patient required surgical correction of excessive postoperative bleeding. Kaplan-Meier curves showed overall survival of 0.94 (95% confidence intervals, 0.9-0.99). We consider our approach an easy, effective way to minimize bleeding from the anastomoses and at the aortic root--a common challenge in aortic surgery.  相似文献   
92.
Aim: To determine the prevalence of vitamin D hypovitaminosis among obese and overweight schoolchildren.Design: A cross−sectional population based sample.Methods: In a cross−sectional study, 301 students (177 girls and 124 boys) aged 11−19 years were selected by multistage stratified sampling design. Subjects were classified according to their body mass index as obese, overweight and normal. Serum 25−hydroxyvitamin D (25−OHD), intact parathyroid hormone (iPTH) and alkaline phosphatase (ALP) were measured in late winter months. Vitamin D deficiency was defined as a 25−OHD 20 ng/ml.Results: The prevalence of hypovitaminosis D was found as 65% in all students. Vitamin D deficiency was found in 12% and insufficiency in 53% of all students. Vitamin D deficiency in female students was about two times more common than in males. In obese and overweight schoolchildren with hypovitaminosis D, serum 25−OHD levels decreased as BMI increased. There were no correlations between serum 25−OHD and ALP and iPTH levels.Conclusion: Vitamin D deficiency and insufficiency are common in obese and overweight schoolchildren, especially in girls. Obesity could be a risk factor in terms of hypovitaminosis D in adolescents. Vitamin D supplementation should be administered particularly to adolescent girls.Conflict of interest:None declared.  相似文献   
93.
94.
The term frontotemporal lobar degeneration (FTLD) refers to a group of neurodegenerative disorders that target the frontal and temporal lobes. It accounts for approximately 10 % of pathologically confirmed dementias but has been demonstrated to be as prevalent as Alzheimer’s disease in patients below the age of 65. The 3 major clinical syndromes associated with FTLD include behavioral variant frontotemporal dementia, semantic and nonfluent variants of primary progressive aphasia. The more recently introduced term logopenic variant appears to represent an atypical form of Alzheimer’s disease in the majority of cases. The neuropathology underlying these clinical syndromes is very heterogeneous and does not correlate well with the clinical phenotype. This causes great difficulties in early and reliable diagnosis and treatment of FTLD. However, significant advances have been made in recent years via the application of magnetic resonance imaging and positron emission tomography imaging methods as biomarkers. The current review aims to provide a synopsis on the value of magnetic resonance imaging-based and molecular imaging procedures in FTLD.  相似文献   
95.
96.
Hemophagocytic lymphohistiocytosis (HLH) is a clinical condition which result in cytotoxic Tcell and antigen presenting cell overproduction and also their cytokines. Hepatitis A Virus associated HLH is very rare condition among other viruses. This condition is often difficult to diagnose, so treatment is often delayed. Here we present a case of adolescent boy with secondary virus associated HLH diagnosis with Hepatitis A infection and successfull treatment by short course of intravenous immunoglobulin and steroid.  相似文献   
97.
The Src kinase family comprises nine homologous members whose distinct expression patterns and cellular distributions indicate that they have unique roles. These roles have not been determined because genetic manipulation has not produced clearly distinct phenotypes, and the kinases’ homology complicates generation of specific inhibitors. Through insertion of a modified FK506 binding protein (insertable FKBP12, iFKBP) into the protein kinase isoforms Fyn, Src, Lyn, and Yes, we engineered kinase analogs that can be activated within minutes in living cells (RapR analogs). Combining our RapR analogs with computational tools for quantifying and characterizing cellular dynamics, we demonstrate that Src family isoforms produce very different phenotypes, encompassing cell spreading, polarized motility, and production of long, thin cell extensions. Activation of Src and Fyn led to patterns of kinase translocation that correlated with morphological changes in temporally distinct stages. Phenotypes were dependent on N-terminal acylation, not on Src homology 3 (SH3) and Src homology 2 (SH2) domains, and correlated with movement between a perinuclear compartment, adhesions, and the plasma membrane.Since its discovery, c-Src (1) has been subject to intensive research into its cellular functions and regulation. Whereas c-Src is the best-studied protooncogene, less is known about the other, closely related Src family kinase (SFK) members. Their high degree of similarity in structure and regulation suggests that SFKs can partially compensate for each other in vivo. Indeed, knockout studies have shown that only mice deficient in all three genes (src, yes, and fyn) show embryonic lethality (2). Early studies demonstrated that disruption of Src or Fyn genes individually resulted only in subtle changes in function of a few cell types (e.g., osteoclasts for src−/−, and T cells for fyn−/−) (3, 4). Roche et al. provided strong evidence that Src, Yes, and Fyn substitute for each other during cell cycle progression (5). These studies suggested that there is a high degree of functional redundancy among Src family kinases.Nonetheless, emerging evidence indicates that Src and Fyn regulate distinct processes in the same cell. Down-regulation of Fyn expression enhances VEGF-stimulated migration of endothelial cells, whereas down-regulation of Src does not (6). Differences in the transforming capacity of SFKs are thought to depend on their affinity for cholesterol-enriched membrane microdomains, which is determined in part by their N-terminal lipid modifications (7, 8). Src has higher tumorigenic potential than Fyn in prostate epithelium, and this is differently affected by alterations in N-terminal palmitoylation (9). Previous studies have shown that Src localizes to perinuclear endosomal compartments and translocates to the plasma membrane upon activation (1012), whereas Fyn localizes to the plasma membrane regardless of its activity (13, 14). Although these studies suggest that localization is important in differentiating the actions of the two kinases, they do not identify specific roles associated with particular subcellular locations.Various techniques have been applied to elucidate the differences in signaling specificity of SFKs. Kinase–substrate interactions have been examined using purified substrates (15). Mutated kinases with selectivity for radiolabeled ATP analogs have identified directly phosphorylated substrates of Src (16). These methods were restricted to cell lysates or purified proteins, and so were unable to address the role of cellular localization in substrate specificity.To dissect the unique role of different SFK isoforms (24, 17, 18) in living cells, we engineered regulatable analogs of Fyn, Yes, and LynA kinases using our rapamycin-regulated activation (RapR) strategy, which has been developed using Src as a prototype (19, 20). Insertable FKBP12 (iFKBP, a truncated form of FKBP) was inserted into the catalytic domain of each SFK, which abolished their kinase activity. Activity was rescued by treating cells with rapamycin in the presence of the FKBP12-rapamycin binding domain (FRB) (Fig. 1A). Molecular dynamics studies have indicated that heterodimerization of the inserted iFKBP with FRB likely reduces the conformational mobility of the kinase G loop, restoring ATP binding (3, 21).Open in a separate windowFig. 1.Design of RapR kinases. (A) Schematic representation of the approach used to regulate catalytic activity of SFKs. The insertion of iFKBP at a highly conserved site in the catalytic domain of each kinase resulted in loss of kinase activity. Catalytic activity was restored by rapamycin, which induced binding of iFKBP and coexpressed FRB. (B) Sequence alignment of SFKs shows that there is a well-defined loop where iFKBP is inserted (blue). It is linked to the G loop (red) through a β-sheet in each SFK.These analogs enabled activation of each isoform specifically, within minutes, resulting in clear phenotypic differences. Unlike genetic modifications of cell populations, there was little time for the cell to compensate for kinase activation before observation. The induced cell behaviors occurred in a succession of stages, associated with changes in the subcellular distribution of each kinase. We focused on Src and Fyn, developing quantitative tools to carefully characterize the kinetics of induced behaviors and associated localization dynamics. Our results indicated that Src’s unique ability to induce polarized movement shortly after kinase activation results from its localization in a perinuclear compartment, where it phosphorylates substrates that traffic on microtubules to the cell perimeter. Both the localization dynamics and phenotype differences between Src and Fyn were dependent on N-terminal lipid modifications, and not on SH2 and SH3 domain interactions.  相似文献   
98.
European Journal of Nuclear Medicine and Molecular Imaging - Immunotherapy has improved outcomes for patients with non-small cell lung cancer (NSCLC), yet durable clinical benefit (DCB) is...  相似文献   
99.

INTRODUCTION

Giant cervical and mediastinal goiter may lead to acute respiratory failure caused by laryngotracheal compression and airway obstruction. Here, we present a case admitted to the emergency service with a giant goiter along with respiratory failure and poor general health status, which required urgent surgical intervention.

PRESENTATION OF CASE

A 71-year-old female admitted to the emergency room with shortness of breath and poor general health status resulting from a giant cervical swelling progressively increased during the last 7 years and constituted severe respiratory failure which has become severe in the last one month. A giant nodular goiter of the left thyroid lobe extending retrosternally, causing tracheal compression, limiting the neck movements was detected with clinical examination and bedside ultrasound. Emergency thyroidectomy was planned. Fiberoptic-assisted awake nasal intubation was performed in the operating room. Emergency total thyroidectomy was performed for the life-threatening respiratory failure. Postoperative period was uneventful. She was transferred from intensive care unit to the ward on postoperative day 3 and was discharged from the hospital on the postoperative 7th day. Benign multinodular hyperplasia was reported on the histopathological report. Patient was included in routine follow-up.

DISCUSSION

In the present case tracheal destruction due to compression of the giant goiter was found in agreement with previous reports. Emergency thyroidectomy was performed after awake intubation since it is a common surgical option for the treatment of giant goiter causing severe airway obstruction.

CONCLUSION

Respiratory failure due to giant nodular goiter is a life-threatening situation and should be treated immediately by performing awake endotracheal intubation following emergency total thyroidectomy.  相似文献   
100.

INTRODUCTION

Synovial chondromatosis is characterized by the presence of metaplastic cartilage nodules originating from the synovia, bursa and tendon sheaths. Although it is extremely rare in the ankle joint, malignant transformation is possible. The choice of treatment is usually open surgery for excision of loose bodies and synovectomy. Limited data is available concerning arthroscopic approaches.

PRESENTATION OF CASE

A 28-year-old male patient was evaluated for pain and swelling of the right ankle joint. Based on the findings of physical examination and radiographic investigations, arthroscopic surgery was performed due to ankle impingement syndrome. A diagnosis of synovial osteochondromatosis was made following the pathological survey.

DISCUSSION

Synovial chondromatosis is slowly progressive and is considered to be a self-limiting situation. Treatment strategies are decided on according to the patient''s complaints, age and disease stage. Open or arthroscopic surgery. can be performed. Some advantages of arthroscopic surgery are wide visualization areas, easy access to areas difficult to reach, lower morbidity, no necessity for casting and immobilization, early rehabilitation and quick recovery period.

CONCLUSION

In conclusion, arthroscopic management can be successful in selected patients with synovial osteochondromatosis localized to the ankle joint.  相似文献   
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