Mann-Whitney U Test (mann-whitney + u_test)

Distribution by Scientific Domains


Selected Abstracts


Follicular variant of papillary carcinoma: Cytologic findings on FNAB samples,experience with 16 cases

DIAGNOSTIC CYTOPATHOLOGY, Issue 2 2001
Franco Fulciniti M.D.
Abstract Between January 1, 1992 and December 31, 1997, a cytopathological diagnosis of follicular variant of papillary thyroid carcinoma (FVPC) was made on a series of 16 out of 18 patients with palpable nodules who underwent fine-needle aspiration biopsy (FNAB) in our Department. The results of aspiration biopsy were followed by histopathological examination of the surgically excised tissues. There were three false-negative aspirations (16.6%), of which two were probably bound to fine-needle sampling and one due to a mixture of benign and malignant cells which had originally gone unrecognized. The accuracy of the cytopathologic diagnosis in this variant was 88.8%. An analysis of the diagnostic cytopathological criteria was performed, which demonstrated the importance of both architectural features (monolayered and branching sheets, microacinar structures, and their combinations) and nuclear features (presence of nuclear grooves). Background -bound features were mainly represented by dense, nonfilamentous colloid. The cytopathologic findings in FVPC were compared to those found in a series of 10 usual papillary carcinomas (UPC) and 10 follicular neoplasms (FN). These latter had originally been diagnosed by FNAB and were subsequently classified histologically as follicular adenoma (n = 6), follicular carcinoma (n = 3), or adenomatoid colloid nodule (n = 1). Statistical evaluation was performed on the cytopathological findings in the three classes of lesions (FVPC, UPC, and FN) as to their presence and relative frequency or absence by using a nonparametric one-way ANOVA (Kruskall-Wallis) and, where necessary, a Mann-Whitney U test. Papillary cellular fragments and multinucleated giant cells (P < 0.005), nonfilamentous dense colloid, squamoid cells, and syncytia were significantly more represented in UPC than in FVPC (P < 0.05), while histiocytes were significantly more frequent in FVPC (P < 0.005). Other nuclear and/or background features were significant only in the distinction between papillary carcinomas as a group and FN. The cytological differential diagnosis of the FVPC is briefly discussed with relevance to the possible pitfalls caused by its peculiar cyto- and histomorphology. Diagn. Cytopathol. 2001;25:86,93. © 2001 Wiley-Liss, Inc. [source]


IL-10 promoter haplotype influence on interferon treatment response in multiple sclerosis

EUROPEAN JOURNAL OF NEUROLOGY, Issue 3 2005
S. Wergeland
The level of interleukin-10 (IL-10) expression is related to polymorphisms -1082 (G/A), -819 (T/C) and -592 (A/C) in the promoter region of the IL-10 gene, which constitute three haplotypes, GCC, ATA, and ACC. The ATA (a non-GCC) haplotype, which is associated with low IL-10 expression, has been shown to improve interferon (IFN) treatment response in hepatitis C. We analysed the distribution of IL-10 promoter haplotype combinations to determine whether they could influence initial IFN treatment response in 63 patients with relapsing-remitting multiple sclerosis (MS). The patients were grouped into non-GCC or GCC haplotypes, and the clinical and magnetic resonance imaging (MRI) disease activity was compared in the two groups. During the first 6 months of treatment, MS patients with non-GCC haplotypes experienced fewer new MRI T1-contrast enhancing lesions [0.77 ± 0.36 (SEM)] than patients with the GCC haplotype (2.45 ± 0.57) (P = 0.05, Mann-Whitney U test). No differences were detected on clinical disease activity. The results suggest an influence of IL-10 promoter polymorphisms on IFN treatment response in MS. [source]


The role of Doppler sonography in predicting severity of acute pancreatitis

JOURNAL OF CLINICAL ULTRASOUND, Issue 3 2008
Naile Bolca Topal MD
Abstract Purpose To investigate the role of Doppler sonography (DUS) examination of major abdominal arteries in predicting severity of acute pancreatitis (AP). Methods Twenty-nine patients diagnosed with AP and 14 controls were blindly and prospectively evaluated with Doppler sonography. Disease severity was defined clinically according to acute physiology and chronic health evaluation (APACHE II) score and was classified as severe for APACHE II score ,8. DUS examination included the measurement of peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI), and resistance index (RI) of the celiac artery (CA) and superior mesenteric artery (SMA). Statistical analysis included Mann-Whitney U test, Student t test, and receiver operating characteristic curve analysis. Results Twelve patients had severe AP and 17 had mild AP. PSV, EDV, and PI of the CA and RI of the SMA were higher in the severe AP group than in the mild AP and control groups (p < 0.001 and p < 0.0001, respectively). The sensitivity and specificity were 100% and 94%, respectively, for a 87 cm/second CA PSV cutoff value, 75% and 100%, respectively, for a 22 cm/second CA EDV cutoff value, 92% and 82%, respectively, for a 1.29 CA PI cutoff value, and 100% and 100%, respectively, for a 0.86 SMA RI cutoff value. Conclusion DUS can be useful in predicting the severity of AP in the early period of admission phase of the disease. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2008 [source]


Vascular endothelial growth factor 121 and 165 in the subacromial bursa are involved in shoulder joint contracture in type II diabetics with rotator cuff disease

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2003
Akiyoshi Handa
Vascular endothelial growth factor (VEGF) is a glycoprotein that plays an important role in neovascularization and increases vascular permeability. We reported that VEGF is involved in motion pain of patients with rotator cuff disease by causing synovial proliferation in the subacromial bursa (SAB). The present study investigates whether VEGF is also involved in the development of shoulder contracture in diabetics with rotator cuff disease. We examined 67 patients with rotator cuff disease, including 36 with complete cuff tears, 20 with incomplete tears, and 11 without apparent tears (subacromial bursitis). The patients were into groups according to the presence or absence of diabetes (14 type II diabetics and 53 non-diabetics). Specimens of the synovium of the SAB were obtained from all patients during surgery. Expression of the VEGF gene in the synovium of the subacromial bursa was evaluated by using the reverse transcriptase polymerase chain reaction. The VEGF protein was localized by immunohistochemistry, and the number of vessels was evaluated based on CD34 immunoreactivity. The results showed that VEGF mRNA was expressed in significantly more diabetics (100%, 14/14) than in non-diabetics (70%, 37/53) (P = 0.0159, Fisher's test). Investigation of VEGF isoform expression revealed VEGF121 in all 14 diabetics and in 37 of the 53 non-diabetics, VEGF 165 in 12 of the 14 diabetics and in 21 of the 53 non-diabetics, and VEGF 189 in 1 of the 14 diabetics and in 2 of the 53 non-diabetics. No VEGF206 was expressed in either group. VEGF protein was localized in both vascular endothelial cells and synovial lining cells. The mean number of VEGF-positive vessels and the vessel area were also significantly greater in the diabetics (p < 0.015, Mann-Whitney U test). Synovial proliferation and shoulder joint contracture were more common in the diabetics (P = 0.0329 and P = 0.073, respectively; Fisher's test). The mean preoperative range of shoulder motion significantly differed in terms of elevation between two groups: 103.8° in diabetics and 124.9° in no diabetics (p = 0.0039 Mann,Whitney U test). In contrast, external rotation did not significantly differ: 44° in diabetics and 49° in non-diabetics (p ° 0.4957, Mann,Whitney U test). These results suggest that VEGF121 and VEGF165 expression in the SAB is responsible for the development of shoulder joint contracture, especially in elevation, among type II diabetic patients with rotator cuff disease. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source]


Cigarette smoking is associated with an increased incidence of vascular complications after liver transplantation

LIVER TRANSPLANTATION, Issue 7 2002
Surakit Pungpapong
Hepatic artery thrombosis (HAT) and other vascular complications are significant causes of morbidity after liver transplantation. Although cigarette smoking increases the risk of vascular complications after renal transplantation, its impact after liver transplantation remains unknown. Between May 1995 and April 2001, 288 liver transplantations were performed in 263 patients. Vascular complications developed in 39 patients (13.5%) (arterial complications, 28 patients [9.7%]; venous complications, 11 patients [3.8%]). Patient demographics, comorbid illnesses, and risk factors were analyzed using the Mann-Whitney U test, Chi-squared test, and Fisher's exact test. In patients with a history of cigarette smoking, incidence of vascular complications was higher than in those without history of cigarette smoking (17.8% v 8%, P = .02). Having quit cigarette smoking 2 years before liver transplantation reduced the incidence of vascular complications by 58.6% (24.4% v 11.8%, P = .04). The incidence of arterial complications was also higher in patients with a history of cigarette smoking compared with those without such history (13.5% v 4.8%, P = .015). Cigarette smoking cessation for 2 years also reduced the risk of arterial complications by 77.6% (21.8% v 5.9%, P =.005). However, the incidence of venous complications was not associated with cigarette smoking. Furthermore, there was no significant association between development of vascular complications and all other characteristics studied. Cigarette smoking is associated with a higher risk for developing vascular complications, especially arterial complications after liver transplantation. Cigarette smoking cessation at least 2 years before liver transplantation can significantly reduce the risk for vascular complications. Cigarette smoking cessation should be an essential requirement for liver transplantation candidates to decrease the morbidity arising from vascular complication after liver transplantation. [source]


Shock Coordinated with High Power of Morphology Electrogram Improves Defibrillation Success in Patients with Implantable Cardioverter Defibrillators

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2002
ALEXANDER BERKOWITSCH
BERKOWITSCH, A., et al.: Shock Coordinated with High Power of Morphology Electrogram Improves Defibrillation Success in Patients with Implantable Cardioverter Defibrillators. Animal studies have suggested that the success of defibrillation may depend on the properties of VF waveform obtained from the morphology electrogram (ME) at the time of the shock. The reliable identification of depolarization events in the fibrillatory signal can be achieved using adaptive estimation of the instantaneous signal power (P). The aim of this study was to investigate if a high P of the ME (PME) was related to ventricular DFT and if the upslope in ME can be associated with the depolarization event. A total of 575 VF (mean duration 10 s) episodes recorded and stored during ICD implantation in 77 patients with ventricular arrhythmias were used for analysis. The DFT was defined using a double step-down test. The values of PME immediately before pulse delivery (Pshock) and shock outcomes were registered. The differences between Pshock of successful and failed defibrillation were tested with the Mann-Whitney U test. The relationship between individual medians of Pshock (Pmed) and DFT was analyzed using the Kruskall-Wallis H-test. The coincidence between identified depolarization and upslope in ME was tested using the chi-square test. A P value of 0.05 was set for an error probability. The Pshock in case of failed defibrillation was significantly lower than Pshock in successful cases by the pulses of any strength (P < 0.001). The test revealed a significant inverse correlation between Pmed and DFT with P < 0.001. The depolarization corresponded to the upslope of ME in 85% of cases. This study demonstrated that a high value of instantaneous power of ME indicates the optimal time for shock delivery. The implementation of this algorithm in ICDs may improve the defibrillation efficacy. [source]


Prognostic value of bone marrow angiogenesis in multiple myeloma: Use of light microscopy as well as computerized image analyzer in the assessment of microvessel density and total vascular area in multiple myeloma and its correlation with various clinical, histological, and laboratory parameters

AMERICAN JOURNAL OF HEMATOLOGY, Issue 9 2006
Sahibinder Singh Bhatti
Abstract We studied the prognostic value of parameters of angiogenesis on bone marrow biopsies in newly diagnosed multiple myeloma (MM) patients. Angiogenesis parameters studied were the microvessel count done manually on light microscopy (MVD-A), microvessel count done by using computerized image analyzer (MVD-B), and total vascular area (TVA) measured by computerized image analyzer. One hundred ten newly diagnosed cases of MM treated at Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, were analyzed with respect to clinical features, laboratory findings, histological features, angiogenesis parameters, and responses to the treatment on follow-up. Twenty age- and sex-matched controls were studied for comparing with angiogenesis of the test cases. Bone marrow microvessels were examined using immunohistochemical staining for CD34. MVD-A (range 4.9,85.2; mean 28.2; SD 19.4), MVD-B (range 2.0,26.9; mean 11.7; SD 5.9), and TVA measured in percentage (range 0.1,17.1; mean 2.4; SD 2.5) were measured for test cases (n = 110). Grading of angiogenesis parameters of the test cases were done; such that angiogenesis parameters of controls (taken as baseline) were grade I. There was a statistically highly significant correlation between (MVD-A vs MVD-B, pcc = 0.92; MVD-A vs TVA, pcc = 0.78; MVD-B vs TVA, pcc = 0.76). The myeloma cases had significantly higher angiogenesis parameters when compared with controls (Kruskall-Wallis test, P < 0.001). "Complete responders" (n = 38/110) had significant lower angiogenesis (Mann-Whitney U test, P < 0.001) than "nonresponders" (n = 72/110). On treatment follow-up "rapid disease progressors" had the highest levels of angiogenesis (mean rank for MVD-A = 84.7, MVD-B = 82.1, and TVA = 81.1). On multivariate (logistic regression) analysis, factors found to have independent prognostic significance in complete responders (adjusted odd ratio (95% CI, P value)] were: (a) MVD-B grade I [0.134 (0.10,0.16, P < 0.001)], (b) clinical substage A [0.163 (0.12,0.19, P = 0.008)], (c) Bartl's histological stage II & I [0.262 (0.2,0.32, P = 0.021)], (d) MVD-A grade I [0.28 (0.22,0.36, P = 0.03)], (e) ,2 microglobulin levels less than 3,400 ng/dl [0.31 (0.23,0.42, P = 0.04)]. Kaplan-Meier survival analysis for myeloma-related death (n = 16) shows a mean survival time (in months) of 24.75; SE = 3; 95% CI = 21,28. We conclude that MVD (particularly MVD-B) is a very good predictor for the complete response in patients of MM and should be done routinely on bone marrow biopsies. Am. J. Hematol., 2006. © 2006 Wiley-Liss, Inc. [source]


Long-interval T2-weighted subtraction magnetic resonance imaging: A powerful new outcome measure in multiple sclerosis trials

ANNALS OF NEUROLOGY, Issue 5 2010
Bastiaan Moraal MD
Objective To compare long-interval T2-weighted subtraction (T2w-Sub) imaging with monthly gadolinium-enhanced T1-weighted (Gd-T1w) imaging for (1) detection of active lesions, (2) assessment of treatment efficacy, and (3) statistical power, in a multiple sclerosis (MS), phase 2, clinical trial setting. Methods Magnetic resonance imaging (MRI) data over 9 months from 120 patients (61 treatment, 59 placebo) from the oral temsirolimus trial were used. T2w-Sub images were scored for active lesions, independent of the original reading of the monthly Gd-T1w images. Treatment efficacy was evaluated using the nonparametric Mann-Whitney U test, and parametric negative binomial (NB)-regression and power calculations were conducted. Results Datasets from 116 patients (58 treatment, 58 placebo) were evaluated. The mean number of T2w-Sub lesions in the treatment group was 3.0 (±4.6) versus 5.9 (±8.8) for placebo; the mean cumulative number of new Gd-T1w lesions in the treatment group was 5.5(±9.1) versus 9.1(±17.2) for placebo. T2w-Sub imaging showed increased power to assess treatment efficacy compared with Gd-T1w imaging, when evaluated by Mann-Whitney U test (p = 0.017 vs p = 0.177), or NB-regression without (p = 0.011 vs p = 0.092) or with baseline adjustment (p < 0.001 vs p = 0.002). Depending on the magnitude of the simulated treatment effect, sample size calculations showed reductions of 22 to 34% in the number of patients (translating into reductions of 81,83% in the number of MRI scans) needed to detect a significant treatment effect in favor of T2w-Sub imaging. Interpretation Compared with monthly Gd-T1w imaging, long-interval T2w-Sub MRI exhibited increased power to assess treatment efficacy, and could greatly increase the cost-effectiveness of phase 2 MS trials by limiting the number of patients, contrast injections, and MRI scans needed. ANN NEUROL 2010;67:667,675 [source]


Lesional and nonlesional skin from patients with untreated juvenile dermatomyositis displays increased numbers of mast cells and mature plasmacytoid dendritic cells

ARTHRITIS & RHEUMATISM, Issue 9 2010
Sheela Shrestha
Objective To investigate the distribution of mast cells and dendritic cell (DC) subsets in paired muscle and skin (lesional/nonlesional) from untreated children with juvenile dermatomyositis (DM). Methods Muscle and skin biopsy samples (4 skin biopsy samples with active rash) from 7 patients with probable/definite juvenile DM were compared with muscle and skin samples from 10 healthy pediatric controls. Mast cell distribution and number were assessed by toluidine blue staining and analyzed by Student's t -test. Immunohistochemical analysis was performed to identify mature DCs, myeloid DCs (MDCs), and plasmacytoid DCs (PDCs) by using antibodies against DC-LAMP, blood dendritic cell antigen 1 (BDCA-1), and BDCA-2, respectively. Myxovirus resistance protein A (MxA) staining indicated active type I interferon (IFN) signaling; positive staining was scored semiquantitatively and analyzed using the Mann-Whitney U test. Results Both inflamed and nonlesional skin from patients with juvenile DM contained more mast cells than did skin from pediatric controls (P = 0.029), and comparable numbers of mast cells were present in lesional and nonlesional skin. Interestingly, mast cell numbers were greater in skin than in paired muscle tissue from patients with juvenile DM (P = 0.014) and were not increased in muscle from patients with juvenile DM compared with control muscle. Both muscle and skin from patients with juvenile DM showed more mature PDCs and MxA staining than did their corresponding control tissues (P < 0.05). In both muscle and skin from patients with juvenile DM and in pediatric control muscle, there were fewer MDCs than PDCs, and the distributions of MDCs and PDCs were similar in pediatric control skin samples. Conclusion The identification of mast cells in skin (irrespective of rash) from patients with juvenile DM, but not in paired muscle tissue, suggests that they have a specific role in juvenile DM skin pathophysiology. In skin from patients with juvenile DM, increased numbers of PDCs and increased expression of type I IFN,induced protein suggest a selective influence on T cell differentiation and subsequent effector function. [source]


Mann-Whitney U test and Kruskal-Wallis test should be used for comparisons of differences in medians, not means: Comment on the article by van der Helm-van Mil et al

ARTHRITIS & RHEUMATISM, Issue 5 2009
Bin Zhang ScD
No abstract is available for this article. [source]


End-tidal Carbon Dioxide Measurements in Children with Acute Asthma

ACADEMIC EMERGENCY MEDICINE, Issue 12 2007
Bridgette D. Guthrie MD
Objectives A noninvasive method to assess ventilation may aid in management of children with acute asthma. The purpose of this study was to evaluate the association between end-tidal carbon dioxide (EtCO2) values and disease severity among children with acute asthma. Methods This was a prospective, blinded, observational study of children 3,17 years old treated for acute asthma in a pediatric emergency department (ED). EtCO2 measurements were taken before the initiation of therapy and after each nebulization treatment (maximum of three). Peak expiratory flow rate (PEFR), Pediatric Asthma Severity Score (PASS), oxygen saturation, and disposition were recorded. Treating physicians, unaware of the EtCO2 results, made all treatment decisions, including disposition. Results One hundred children were enrolled. The mean initial EtCO2 value was 35 mm Hg (95% confidence interval = 34.3 to 36.1 mm Hg). The mean disposition EtCO2 value was 33.3 mm Hg (95% confidence interval = 32.6 to 34.4 mm Hg). PEFR measures were completed on 43 patients and PASS recorded on 100 patients. There was an overall trend toward lower EtCO2 values during treatment (p < 0.01). Sixteen patients were admitted. Initial EtCO2 values were lower among children admitted to the hospital (35.6 mm Hg vs. 32.9 mm Hg; Mann-Whitney U test; p < 0.02). EtCO2 values at disposition did not differ between groups based on PEFR, PASS, or hospital admission. Conclusions Noninvasive bedside measurement of EtCO2 values among children with acute asthma is feasible. EtCO2 values did not distinguish children with mild disease from those with more severe disease. Further data are needed to clarify the association between EtCO2 values and other indicators of disease severity, particularly in children with more severe disease. [source]


Endothelial Microparticle Levels Are Similar in Acute Ischemic Stroke and Stroke Mimics Due to Activation and Not Apoptosis/Necrosis

ACADEMIC EMERGENCY MEDICINE, Issue 8 2007
Justin B. Williams MD
BackgroundEndothelial microparticles (EMPs) are <2-,m membranous blebs from endothelial cell membranes that have been demonstrated to be elevated in vasculopathic conditions. One study has demonstrated elevated EMPs in acute ischemic stroke (AIS) versus age- and comorbidity-matched controls. ObjectivesTo determine the level of EMPs in stroke mimics and AIS and determine if EMPs are released as a result of activation or apoptosis/necrosis in AIS. MethodsEMP levels in plasma of patients with AIS and stroke mimic patients were quantified by flow cytometry. Stroke status was verified in all patients by magnetic resonance imaging. Patients were matched for age and comorbidities. Markers for apoptosis/necrosis (platelet/endothelial cell adhesion molecule-1 [PECAM-1]/CD31 antigen) and activation (E-selectin/CD62e antigen) were compared. A PECAM-1/E-selectin ratio of >4.0 was used to determine whether EMPs were generated via activation or apoptosis/necrosis. Data were compared between groups using the Mann-Whitney U test. ResultsEMP levels were similar in stroke mimic patients when compared with AIS; there was no difference between groups (PECAM-1, p = 0.393; E-selectin, p = 0.579). The PECAM-1/E-selectin ratio was also similar for AIS and stroke mimics, and all were >4.0. ConclusionsEMP levels were similar in patients with AIS and stroke mimic patients. The PECAM-1/E-selectin ratio demonstrated that EMPs were generated via activation and not apoptosis/necrosis. This suggests that EMPs may not be a good marker for AIS, given the inability to discriminate between stroke mimics and AIS. [source]