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61.
Jyotindu Debnath Rajesh Kumar Ankit Mathur Pawan Sharma Nikhilesh Kumar Nagaraj Shridhar Ashwani Shukla Shiv Pankaj Khanna 《The Indian journal of surgery》2015,77(2):221-226
The purposes of this study were to revisit the utility of ultrasonography (USG) as a primary imaging modality in acute appendicitis (AA) and to establish the role of CT scan as a second-line/problem-solving modality. All cases of suspected AA were referred for urgent USG. USG was done with standard protocol for appendicitis. Limited computed tomographic (CT) scan [NCCT ± CECT (IV contrast only)] was done for the lower abdomen and pelvis where sonographic findings were equivocal. One hundred and twenty-one patients were referred for USG for suspected appendicitis. Eight-four patients underwent surgery for AA based on clinical as well as imaging findings, of whom 76 had appendicitis confirmed at histopathology. Three patients were misdiagnosed (3.6 %) on USG as appendicitis. Of 76 patients of appendicitis confirmed histopathologically, 63 (82.8 %) had features of appendicitis on USG and did not require any additional imaging modality. Of 121 patients, 12 (10 %) needed CT scan because of atypical features on USG. Of these 12 patients, seven had retrocecal appendicitis, and three high-up paracolic appendicitis. USG alone had sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of 81, 88, 92.6, 71.6, and 83 %, respectively. When combined with CT scan in select cases, the sensitivity, specificity, PPV, NPV, and accuracy of combined USG + CT scan were 96 % (P?=?0.0014), 89 %, 93 %, 93.5 % (P?=?0.0001), and 93 % (P?=?0.0484), respectively. Twenty-eight (23 %) patients were given alternative diagnosis on USG. Dedicated appendiceal USG should be used as a primary imaging modality in diagnosing or excluding AA. Appendiceal CT can serve as a problem-solving modality. 相似文献
62.
P Kulshrestha B Das K S Iyer A Sampathkumar M L Sharma I M Rao U Kaul S Srivastava M L Bhatia P Venugopal 《International journal of cardiology》1989,23(1):19-26
Seventy-eight patients undergoing mitral valve surgery with or without replacement of the aortic valve also underwent procedures on the tricuspid valve over a period of 10 years. All patients were in functional class III or IV preoperatively. The procedures were performed in all patients with organic disease of the tricuspid valve (N = 44) and in those with moderate or severe functional tricuspid valvar regurgitation (N = 34). Seventy-one patients underwent DeVega's annuloplasty with or without commissurotomy. The overall mortality was 11.5%. 65 long-term survivors were followed up for a period of 6 months to 10 years (mean 5.3 years). Sixty-three patients were in functional class I or II at the last follow-up. Six patients had clinical evidence of mild to moderate tricuspid regurgitation. Regression of cardiomegaly (as judged by the chest radiograph and right ventricular hypertrophy seen in the electrocardiogram) was evident in most cases. Fifty-one of 54 patients evaluated by cross-sectional echocardiography were reported to have a functionally normal tricuspid valve. Doppler echocardiography in 28 patients showed no significant tricuspid regurgitation or stenosis in 26 patients. Eleven consecutive patients undergoing DeVega's annuloplasty were studied prospectively with pre- and postoperative Doppler echocardiography. Good correlation existed between right ventricular systolic pressures predicted by Doppler with those obtained preoperatively at cardiac catheterization. Postoperative Doppler echocardiography in these 11 patients showed complete restoration of competence of the tricuspid valve as well as normalisation of the right ventricular systolic pressure in 10 patients. 相似文献
63.
64.
Arunaloke Chakrabarti Prashant Sood Shivaprakash M. Rudramurthy Sharon Chen Harsimran Kaur Malini Capoor Deepinder Chhina Ratna Rao Vandana Kalwaje Eshwara Immaculata Xess Anupama J. Kindo P. Umabala Jayanthi Savio Atul Patel Ujjwayini Ray Sangeetha Mohan Ranganathan Iyer Jagdish Chander Anita Arora Raman Sardana Indranil Roy B. Appalaraju Ajanta Sharma Anjali Shetty Neelam Khanna Rungmei Marak Sanjay Biswas Shukla Das B. N. Harish Sangeeta Joshi Deepak Mendiratta 《Intensive care medicine》2015,41(2):285-295
65.
Benjamin T. Bjerke Zoe B. Cheung Grant D. Shifflett Sravisht Iyer Peter B. Derman Matthew E. Cunningham 《HSS journal》2015,11(3):216-222
Background
Shoulder balance for adolescent idiopathic scoliosis (AIS) patients is associated with patient satisfaction and self-image. However, few validated systems exist for selecting the upper instrumented vertebra (UIV) post-surgical shoulder balance.Questions/Purposes
The purpose is to examine the existing UIV selection criteria and correlate with post-surgical shoulder balance in AIS patients.Methods
Patients who underwent spinal fusion at age 10–18 years for AIS over a 6-year period were reviewed. All patients with a minimum of 1-year radiographic follow-up were included. Imbalance was determined to be radiographic shoulder height |RSH| ≥ 15 mm at latest follow-up. Three UIV selection methods were considered: Lenke, Ilharreborde, and Trobisch. A recommended UIV was determined using each method from pre-surgical radiographs. The recommended UIV for each method was compared to the actual UIV instrumented for all three methods; concordance between these levels was defined as “Correct” UIV selection, and discordance was defined as “Incorrect” selection.Results
One hundred seventy-one patients were included with 2.3 ± 1.1 year follow-up. For all methods, “Correct” UIV selection resulted in more shoulder imbalance than “Incorrect” UIV selection. Overall shoulder imbalance incidence was improved from 31.0% (53/171) to 15.2% (26/171). New shoulder imbalance incidence for patients with previously level shoulders was 8.8%.Conclusions
We could not identify a set of UIV selection criteria that accurately predicted post-surgical shoulder balance. Further validated measures are needed in this area. The complexity of proximal thoracic curve correction is underscored in a case example, where shoulder imbalance occurred despite “Correct” UIV selection by all methods.Electronic supplementary material
The online version of this article (doi:10.1007/s11420-015-9451-y) contains supplementary material, which is available to authorized users. 相似文献66.
Ma X Helgason E Phung QT Quan CL Iyer RS Lee MW Bowman KK Starovasnik MA Dueber EC 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(24):9378-9383
Tank-binding kinase (TBK)1 plays a central role in innate immunity: it serves as an integrator of multiple signals induced by receptor-mediated pathogen detection and as a modulator of IFN levels. Efforts to better understand the biology of this key immunological factor have intensified recently as growing evidence implicates aberrant TBK1 activity in a variety of autoimmune diseases and cancers. Nevertheless, key molecular details of TBK1 regulation and substrate selection remain unanswered. Here, structures of phosphorylated and unphosphorylated human TBK1 kinase and ubiquitin-like domains, combined with biochemical studies, indicate a molecular mechanism of activation via transautophosphorylation. These TBK1 structures are consistent with the tripartite architecture observed recently for the related kinase IKKβ, but domain contributions toward target recognition appear to differ for the two enzymes. In particular, both TBK1 autoactivation and substrate specificity are likely driven by signal-dependent colocalization events. 相似文献
67.
Styles L Wager CG Labotka RJ Smith-Whitley K Thompson AA Lane PA McMahon LE Miller R Roseff SD Iyer RV Hsu LL Castro OL Ataga KI Onyekwere O Okam M Bellevue R Miller ST;Sickle Cell Disease Clinical Research Network 《British journal of haematology》2012,157(5):627-636
Acute chest syndrome (ACS) is defined as fever, respiratory symptoms and a new pulmonary infiltrate in an individual with sickle cell disease (SCD). Nearly half of ACS episodes occur in SCD patients already hospitalized, potentially permitting pre-emptive therapy in high-risk patients. Simple transfusion of red blood cells may abort ACS if given to patients hospitalized for pain who develop fever and elevated levels of secretory phospholipase A2 (sPLA2). In a feasibility study (PROACTIVE; ClinicalTrials.gov NCT00951808), patients hospitalized for pain who developed fever and elevated sPLA2 were eligible for randomization to transfusion or observation; all others were enrolled in an observational arm. Of 237 enrolled, only 10 were randomized; one of the four to receive transfusion had delayed treatment. Of 233 subjects receiving standard care, 22 developed ACS. A threshold level of sPLA2 ≥ 48 ng/ml gave optimal sensitivity (73%), specificity (71%) and accuracy (71%), but a positive predictive value of only 24%. The predictive value of sPLA2 was improved in adults and patients with chest or back pain, lower haemoglobin concentration and higher white blood cell counts, and in those receiving less than two-thirds maintenance fluids. The hurdles identified in PROACTIVE should facilitate design of a larger, definitive, phase 3 randomized controlled trial. 相似文献
68.
Doi H Iyer TK Carpenter E Li H Chang KM Vonderheide RH Kaplan DE 《Hepatology (Baltimore, Md.)》2012,55(3):709-719
Chronic hepatitis C virus (HCV) infection is a leading cause of cirrhosis and hepatocellular carcinoma (HCC). Both advanced solid tumors and HCV have previously been associated with memory B-cell dysfunction. In this study, we sought to dissect the effect of viral infection, cirrhosis, and liver cancer on memory B-cell frequency and function in the spectrum of HCV disease. Peripheral blood from healthy donors, HCV-infected patients with F1-F2 liver fibrosis, HCV-infected patients with cirrhosis, patients with HCV-related HCC, and non-HCV-infected cirrhotics were assessed for B-cell phenotype by flow cytometry. Isolated B cells were stimulated with anti-cluster of differentiation (CD)40 antibodies and Toll-like receptor (TLR)9 agonist for assessment of costimulation marker expression, cytokine production, immunoglobulin (Ig) production, and CD4(+) T-cell allostimulatory capacity. CD27(+) memory B cells and, more specifically, CD27(+) IgM(+) B cells were markedly less frequent in cirrhotic patients independent of HCV infection. Circulating B cells in cirrhotics were hyporesponsive to CD40/TLR9 activation, as characterized by CD70 up-regulation, tumor necrosis factor beta secretion, IgG production, and T-cell allostimulation. Last, blockade of TLR4 and TLR9 signaling abrogated the activation of healthy donor B cells by cirrhotic plasma, suggesting a role for bacterial translocation in driving B-cell changes in cirrhosis. CONCLUSION: Profound abnormalities in B-cell phenotype and function occur in cirrhosis independent of HCV infection. These B-cell defects may explain, in part, the vaccine hyporesponsiveness and susceptibility to bacterial infection in this population. 相似文献
69.
El-Galaly TC Mylam KJ Brown P Specht L Christiansen I Munksgaard L Johnsen HE Loft A Bukh A Iyer V Nielsen AL Hutchings M 《Haematologica》2012,97(6):931-936
Background
The value of performing post-therapy routine surveillance imaging in patients with Hodgkin lymphoma is controversial. This study evaluates the utility of positron emission tomography/computed tomography using 2-[18F]fluoro-2-deoxyglucose for this purpose and in situations with suspected lymphoma relapse.Design and Methods
We conducted a multicenter retrospective study. Patients with newly diagnosed Hodgkin lymphoma achieving at least a partial remission on first-line therapy were eligible if they received positron emission tomography/computed tomography surveillance during follow-up. Two types of imaging surveillance were analyzed: “routine” when patients showed no signs of relapse at referral to positron emission tomography/computed tomography, and “clinically indicated” when recurrence was suspected.Results
A total of 211 routine and 88 clinically indicated positron emission tomography/computed tomography studies were performed in 161 patients. In ten of 22 patients with recurrence of Hodgkin lymphoma, routine imaging surveillance was the primary tool for the diagnosis of the relapse. Extranodal disease, interim positron emission tomography-positive lesions and positron emission tomography activity at response evaluation were all associated with a positron emission tomography/computed tomography-diagnosed preclinical relapse. The true positive rates of routine and clinically indicated imaging were 5% and 13%, respectively (P=0.02). The overall positive predictive value and negative predictive value of positron emission tomography/computed tomography were 28% and 100%, respectively. The estimated cost per routine imaging diagnosed relapse was US$ 50,778.Conclusions
Negative positron emission tomography/computed tomography reliably rules out a relapse. The high false positive rate is, however, an important limitation and a confirmatory biopsy is mandatory for the diagnosis of a relapse. With no proven survival benefit for patients with a pre-clinically diagnosed relapse, the high costs and low positive predictive value make positron emission tomography/computed tomography unsuitable for routine surveillance of patients with Hodgkin lymphoma. 相似文献70.
The STOP‐BANG questionnaire screens for obstructive sleep apnoea. We retrospectively analysed the independent association of pre‐operative variables with postoperative critical care admission using multivariable logistic regression for patients undergoing elective surgery from January to December 2011. Of 5432 patients, 338 (6.2%) were admitted postoperatively to the critical care unit. In multivariate analysis, the odds ratios (95% CI) for critical care admission were: 2.2 (1.1–4.6), p = 0.037; 3.2 (1.2–8.1), p = 0.017; and 5.1 (1.8–14.9), p = 0.002, for STOP‐BANG scores of 4, 5 and ≥ 6, respectively. The odds ratio was also independently increased for: each year of age, 1.015 (1.004–1.026), p = 0.019; asthma, 1.6 (1.1–2.4), p = 0.016; obstructive sleep apnoea, 3.2 (1.9–5.6), p < 0.001; and for ASA physical status 2, 3 and ≥ 4, 2.1 (1.4–3.3), 6.5 (3.9–11.0), 6.3 (2.9–13.8), respectively, p < 0.001 for all. 相似文献