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Exact Test (exact + test)
Kinds of Exact Test Terms modified by Exact Test Selected AbstractsAN EXACT TEST FOR HAZARD SIMILARITYAUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS, Issue 2 2009Kais Hamza Summary An exact test is developed for hazard similarity and in particular for exponentiality. This test is distinct from more common goodness-of-fit tests such as the Kolmogorov,Smirnov goodness-of-fit test, as it does not require full specification of the null distribution. This test is obtained through a characterization of hazard-similar distributions and a generalization of Fisher's test for association. [source] Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 81JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2003S Lori Symptomatic neuropathy in young patients with type 1 Diabetes Mellitus (t1DM) is rare but subclinical peripheral alterations can be assessed by electroclinical evaluation. This study aimed to assess prevalence of clinical and subclinical peripheral neuropathy in patients with t1DM. Motor and/or sensory nerve conduction studies of both median, ulnar, peroneal, tibial and sural nerves and standard clinical examination of peripheral nervous system were performed in 83 patients (27 females and 56 males) with diabetes onset since five years. The mean age of patients was 19.89 (range 9,28.3) years, the mean disease duration was 9.61(range 4.4,19.3) and the mean age at the onset of diabetes was 9.02 (range 0.8,23.5). Five patients (6.02 %) had both symptomatic (light clinical abnormalities as paresthesias and mild reduction of vibratory sensibility) and electrophysiologic neuropathy and six (7.2 %) with mild abnormal nerve conduction studies were totally asymptomatic (subclinical neuropathy). The majority of symptoms and electrophysiological alterations were found on the lower limbs. Only two patients had a minimal distal neuropathy of median nerve. No patients showed laboratory evidence of early renal complications or systemic hypertension; 5 (6.02 %) had early diabetic retinal abnormalities as microaneurisms, seen by fundus examination. Analysis of sex, age of onset, duration of diabetes, age at the date of electrophysiologic examination, Hemoglobin A1c (mean level of the last two years), association with retinal abnormalities and clinical assessment was performed (Fisher Exact Test, ANOVA). No correlation was found with the age at the onset, retinal abnormalities and glycaemic control index. Peripheral neuropathy was significantly related with patient age at the date of electrophysiological study and duration of t1DM. [source] Glut3 Expression in Biopsy Specimens of Laryngeal Carcinoma Is Associated With Poor Survival,THE LARYNGOSCOPE, Issue 2 2002Susan Baer MD Abstract Objectives/Hypothesis The aim of the study was to determine the clinical significance of the expression of Glut1 and Glut3 proteins in biopsy specimens of squamous cell carcinoma (SCC) of the larynx. Study Design A retrospective study. Methods Using immunohistochemistry, we immunostained sections of formalin-fixed, paraffin-embedded tissues from 48 biopsies of invasive SCC of the larynx for Glut1 and Glut3. The percentages of positive cells were recorded, then correlated with overall patient survival using the Kaplan-Meier method and the Breslow-Gehan-Wilcoxon test for statistical significance. Results All cases were positive for Glut1, and Glut1 expression was not associated with survival difference at any cut-off value. Eighteen (38%) of the cases were Glut3-negative and 30 (62%) were Glut3-positive. Glut3-positive cases were associated with poorer survival than Glut3-negative cases (P = .0336). No significant difference was found between Glut3-negative and Glut3-positive groups in respect to sex, tumor site (glottic vs. supraglottic), nodal or distant metastasis, or treatment modality. However, there were significantly more poorly differentiated tumors in the Glut3-positive group than in the Glut3-negative group (27% vs. 0%, respectively;P = .0182, Fisher's Exact Test). After poorly differentiated tumors were excluded from the survival analysis, Glut3 immunoreactivity remained a significant marker of poor prognosis (P = .0385). Conclusion Immunohistochemical detection of Glut3 in biopsy specimens of SCC of the larynx is a marker of poorer prognosis. [source] An Exact Test for the Association Between the Disease and Alleles at Highly Polymorphic Loci with Particular Interest in the Haplotype AnalysisBIOMETRICS, Issue 3 2001Chihiro Hirotsu Summary. The association analysis between the disease and genetic alleles is one of the simple methods for localizing the susceptibility locus in the genes. For revealing the association, several statistical tests have been proposed without discussing explicitly the alternative hypotheses. We therefore specify two types of alternative hypotheses (i.e., there is only one susceptibility allele in the locus, and there is an extension or shortening of alleles associated with the disease) and derive exact tests for the respective hypotheses. We also propose to combine these two tests when the prior knowledge is not sufficient enough to specify one of these two hypotheses. In particular, these ideas are extended to the haplotype analysis of three-way association between the disease and bivariate allele frequencies at two closely linked loci. As a by-product, a factorization of the probability distribution of the three-way cell frequencies under the null hypothesis of no three-way interaction is obtained. [source] Exact Tests using Two Correlated Binomial Variables in Contemporary Cancer Clinical TrialsBIOMETRICAL JOURNAL, Issue 6 2009Jihnhee Yu Abstract New therapy strategies for the treatment of cancer are rapidly emerging because of recent technology advances in genetics and molecular biology. Although newer targeted therapies can improve survival without measurable changes in tumor size, clinical trial conduct has remained nearly unchanged. When potentially efficacious therapies are tested, current clinical trial design and analysis methods may not be suitable for detecting therapeutic effects. We propose an exact method with respect to testing cytostatic cancer treatment using correlated bivariate binomial random variables to simultaneously assess two primary outcomes. The method is easy to implement. It does not increase the sample size over that of the univariate exact test and in most cases reduces the sample size required. Sample size calculations are provided for selected designs. [source] A Comparison of the Three Conditional Exact Tests in Two-way Contingency Tables Using the Unconditional Exact PowerBIOMETRICAL JOURNAL, Issue 3 2004Seung-Ho Kang Abstract The conditional exact tests of homogeneity of two binomial proportions are often used in small samples, because the exact tests guarantee to keep the size under the nominal level. The Fisher's exact test, the exact chi-squared test and the exact likelihood ratio test are popular and can be implemented in software StatXact. In this paper we investigate which test is the best in small samples in terms of the unconditional exact power. In equal sample cases it is proved that the three tests produce the same unconditional exact power. A symmetry of the unconditional exact power is also found. In unequal sample cases the unconditional exact powers of the three tests are computed and compared. In most cases the Fisher's exact test turns out to be best, but we characterize some cases in which the exact likelihood ratio test has the highest unconditional exact power. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Preemptive Low-frequency Stimulation Decreases the Incidence of Amygdala-kindled SeizuresEPILEPSIA, Issue 1 2005Jeffrey H. Goodman Summary:,Purpose: The use of electrical stimulation as a therapy for epilepsy is currently being studied in experimental animals and in patients with epilepsy. This study examined the effect of preemptive, low-frequency, 1-Hz sine wave stimulation (LFS) on the incidence of amygdala-kindled seizures in the rat. Methods: Electrodes were implanted into the basolateral amygdalae of adult male rats. All animals received a kindling stimulus of 60-Hz, 400-,A, sine wave for 1 s twice a day. Experimental animals received an additional LFS consisting of 1 Hz, 50 ,A for 30 s immediately before the kindling stimulus. Afterdischarge (AD) duration, behavioral seizure score, the number of stimulations required to elicit the first stage five seizure and to become fully kindled were measured. After 20 stimulations, a crossover procedure was performed. Fully kindled rats from each group were switched, so that the original controls received LFS plus the kindling stimulus, and the original experimental rats received only the kindling stimulus. Results: During kindling acquisition, LFS induced a significant decrease in AD duration. A significant increase in the number of times the kindling stimulus failed to elicit an AD was noted. Control rats exhibited an AD 99% of the time compared with 70% in experimental rats (p < 0.0001; Fisher's Exact test). In fully kindled animals, the incidence of stage five seizures in the original controls significantly decreased from 98% to 42% (p < 0.0001) when the LFS was added to the kindling paradigm. Conclusions: The dramatic decrease in the incidence of stage 5 seizures in fully kindled animals after preemptive LFS strongly suggests that LFS may be an effective therapy for the prevention of seizures in patients with epilepsy. [source] Outcome of intensive care of homozygous alpha-thalassaemia without prior intra-uterine therapyJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 7-8 2007Shing YR Lee Aim: To review the outcome of homozygous alpha-thalassaemia without prior intra-uterine therapy treated in neonatal intensive care unit and identify the factors associated with survival. Methods: The hospital records of all patients with homozygous alpha-thalassaemia treated in our neonatal intensive care unit in the last 15 years were reviewed. A literature search beginning in the year 1980 was done to identify homozygous alpha-thalassaemia actively treated in neonatal intensive care units. Those receiving prior intra-uterine therapy were excluded. The following information was collected: the severity of hydrops, sizes of liver and spleen, haemoglobin level, Apgar score at 5 min, ventilator settings, timing and forms of red blood cell transfusion and presence of persistent hypoxaemia. The survivors and the non-survivors were compared. Results: In our centre, in the last 15 years there were six infants born with homozygous alpha-thalassaemia who did not receive intra-uterine therapy; one survived and five succumbed despite aggressive respiratory therapy. In our literature search there were more reports of survivors (10) than non-survivors (six) for these infants, suggesting a reporting bias towards selection of rare cases of survival. Apgar score of four or above occurred in seven of the eight survivors with data available in the reports, whereas this occurred in four of the 11 non-survivors (P = 0.035, Fisher Exact test). Five of the 11 survivors had abnormal neurological outcome including developmental delay and spastic quadriplegia. Conclusion: Without prior intra-uterine therapy, homozygous alpha-thalassaemia has grave outlook in terms of mortality and morbidity despite aggressive respiratory therapy. [source] Microbiological analysis of infected root canals from symptomatic and asymptomatic teeth with periapical periodontitis and the antimicrobial susceptibility of some isolated anaerobic bacteriaMOLECULAR ORAL MICROBIOLOGY, Issue 5 2003R. C. Jacinto The purpose of the present study was to investigate the correlation between the composition of the bacterial flora isolated from infected root canals of teeth with apical periodontitis with the presence of clinical signs and symptoms, and to test the antibiotic susceptibility of five anaerobic bacteria mostly commonly found in the root canals of symptomatic teeth against various substances using the E-test. Microbial samples were taken from 48 root canals, 29 symptomatic and 19 asymptomatic, using adequate techniques. A total of 218 cultivable isolates were recovered from 48 different microbial species and 19 different genera. Root canals from symptomatic teeth harbored more obligate anaerobes and a bigger number of bacterial species than the asymptomatic teeth. More than 70% of the bacterial isolates were strict anaerobes. Statistical analysis used a Pearson Chi-squared test or a one-sided Fisher's Exact test as appropriate. Suggested relationships were found between specific microorganisms, especially gram-negative anaerobes, and the presence of spontaneous or previous pain, tenderness to percussion, pain on palpation and swelling amoxicillin, amoxicillin + clavulanate and cephaclor were effective against all the strains tested. The lowest susceptibility rate was presented by Prevotella intermedia/nigrescens against Penicillin G. Our results suggested that specific bacteria are associated with endodontic symptoms of infected teeth with periapical periodontitis and the majority of the anaerobic bacterial species tested were susceptible to all antibiotics studied. [source] ORIGINAL ARTICLE: How Should Data on Murine Spontaneous Abortion Rates be Expressed and Analyzed?AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2008David A. Clark Problem, Spontaneous abortions in the CBA × DBA/2 model are normally reported as number of resorptions/total number of implantations (R/T), pooling data from individual mice. The significance of differences between groups has been determined using non-parametric statistics (e.g. chi-square or Fisher's Exact test) based on a priori predictions. Recently, it has been argued that medians with box plots should replace the accepted standard, but this deprives readers of data needed to verify P -values, and leads to inferences incompatible with biological and statistical reality. Method of study, Raw data on 173 individual CBA × DBA/2 matings were analyzed by median and mean, along with R/T data from 18 independent experiments containing 5,10 mice per group. Raw data from 19 CBA × BALB/c matings were similarly analyzed. Results, Individual CBA × DBA/2 mouse resorption rates showed a non-Gaussian distribution, but the mean and median differed by <0.5%. Resorption data from 6 and 12 independent pools of mice were normally distributed. Only the mean enabled a between-group P -value calculation. CBA × BALB/c matings gave a median of 0 and mean of 5.1%; the data were not normally distributed, but that was because of a bimodal distribution. One group of mice had 0 abortions, and the second a mean of 13.9% abortions, and the data from the latter group were normally distributed. Conclusion, Although it is possible to compare individual mice, and even individual implantation sites, in resorption (abortion) studies, as the relevant question is the significance of differences between treatment groups of mice, and reproducibility, the established classical method of reporting R/T should continue to be provided. In CBA × BALB/c matings, where abortion rates are low, using the median is misleading and may obscure the existence of two distinct populations. [source] Shoulder Disability After Different Selective Neck Dissections (Levels II,IV Versus Levels II,V): A Comparative StudyTHE LARYNGOSCOPE, Issue 2 2005Johnny Cappiello MD Abstract Objectives/Hypothesis: The objective was to compare the results of clinical and electrophysiological investigations of shoulder function in patients affected by head and neck carcinoma treated with concomitant surgery on the primary and the neck with different selective neck dissections. Study Design: Retrospective study of 40 patients managed at the Department of Otolaryngology, University of Brescia (Brescia, Italy) between January 1999 and December 2001. Methods: Two groups of 20 patients each matched for gender and age were selected according to the type of neck dissection received: patients in group A had selective neck dissection involving clearance of levels II,IV, and patients in group B had clearance of levels II,V. The inclusion criteria were as follows: no preoperative signs of myopathy or neuropathy, no postoperative radiotherapy, and absence of locoregional recurrence. At least 1 year after surgery, patients underwent evaluation of shoulder function by means of a questionnaire, clinical inspection, strength and motion tests, electromyography of the upper trapezius and sternocleidomastoid muscles, and electroneurography of the spinal accessory nerve. Statistical comparisons of the clinical data were obtained using the contingency tables with Fisher's Exact test. Electrophysiological data were analyzed by means of Fisher's Exact test, and electromyography results by Kruskal-Wallis test. Results: A slight strength impairment of the upper limb, slight motor deficit of the shoulder, and shoulder pain were observed in 0%, 5%, and 15% of patients in group A and in 20%, 15%, and 15% of patients in group B, respectively. On inspection, in group B, shoulder droop, shoulder protraction, and scapular flaring were present in 30%, 15%, and 5% of patients, respectively. One patient (5%) in group A showed shoulder droop as the only significant finding. In group B, muscle strength and arm movement impairment were found in 25% of patients, 25% showed limited shoulder flexion, and 50% had abnormalities of shoulder abduction with contralateral head rotation. In contrast, only one patient (5%) in group A presented slight arm abduction impairment. Electromyographic abnormalities were less frequently found in group A than in group B (40% vs. 85% [P = .003]), and the distribution of abnormalities recorded in the upper trapezius muscle and sternocleidomastoid muscle was quite different: 20% and 40% in group A versus 85% and 45% in group B, respectively. Only one case of total upper trapezius muscle denervation was observed in group B. In both groups, electroneurographic data from the side of the neck treated showed a statistically significant increase in latency (P = .001) and decrease in amplitude (P = .008) compared with the contralateral side. There was no significant difference in electroneurographic data from the side with and the side without dissection in either group. Even though a high number of abnormalities was found on electrophysiological testing, only a limited number of patients, mostly in group B, displayed shoulder function disability affecting daily activities. Conclusion: The study data confirm that clearance of the posterior triangle of the neck increases shoulder morbidity. However, subclinical nerve impairment can be observed even after selective neck dissection (levels II,IV) if the submuscular recess is routinely dissected. [source] Quality of Life, Functional Outcome, and Costs of Early Glottic Cancer,THE LARYNGOSCOPE, Issue 1 2003Jonathan C. Smith MD Abstract Objective To analyze quality of life, functional outcome, and hidden costs by primary treatment with surgery or radiation therapy in patients with early glottic cancer. Study Design Retrospective study in a tertiary care facility. Methods A group of 101 patients with carcinoma in situ and T1 invasive squamous cell carcinoma treated primarily with either surgery or radiation, between January 1990 and December 2000, were identified from searching our tumor registry. Patients completed two previously validated questionnaires and one local questionnaire. Statistical significance was assessed with the rank sum test, ,2 test, or Fisher's Exact test. Results Questionnaires were completed in 59% (44 of 74) of the surgical cohort and 41% (11 of 27) of the radiation therapy cohort. The primary surgical treatments were endoscopic excision (86%), hemilaryngectomy (12%), and total laryngectomy (1%). Patient-reported problems with swallowing, chewing, speech, taste, saliva, pain, activity, recreation, and appearance showed no difference between the endoscopic excision or radiation therapy cohorts. Comparing endoscopic excision versus radiation therapy, respectively, median number of treatments (2 vs. 35), total median travel distance (150 vs. 660 miles), total median travel time (180 vs. 1440 min), and total median number of hours of work missed (76 vs. 24) all differed significantly (P <.01). Conclusions Almost all patients with early glottic cancer, whether treated with surgery or radiation therapy, reported excellent quality of life outcomes and functional results. In addition to actual costs, the hidden costs for radiation therapy versus endoscopic excision were all greater in terms of total number of hours of work missed, total travel time, and total travel distance. [source] Verapamil augmentation of lithium treatment improves outcome in mania unresponsive to lithium alone: preliminary findings and a discussion of therapeutic mechanismsBIPOLAR DISORDERS, Issue 8 2008Alan G Mallinger Objectives:, Attenuation of protein kinase C (PKC) is a mechanism common to both established (lithium, valproate) and some novel (tamoxifen) antimanic agents. Verapamil, although primarily known as a calcium channel blocker, also has PKC inhibitory activity. Verapamil has shown antimanic activity in some but not all studies. Therefore, we investigated verapamil, used alone or as an adjunctive treatment, in manic patients who did not respond to an initial adequate trial of lithium. Methods:, Each study phase lasted three weeks. Subjects were treated openly with lithium in Phase 1 (n = 45). Those who failed to respond were randomly assigned to double-blind treatment in Phase 2 with either verapamil (n = 10) or continued-lithium (n = 8). Phase 2 nonresponders (n = 10) were assigned to combined verapamil/lithium in Phase 3. Results:, Response in Phase 2 did not differ significantly between verapamil and continued-lithium. During Phase 3, response to combined treatment was significantly better than overall response to monotherapy in Phase 2 (Fisher's Exact test, p = 0.043). Mania ratings improved during combined treatment in Phase 3 by 88.2% (linear mixed model analysis, F = 4.34, p = 0.013), compared with 10.5% improvement during Phase 2. Conclusions:, In this preliminary investigation, verapamil monotherapy did not demonstrate antimanic efficacy. By contrast, the combination of verapamil plus lithium was highly efficacious. Our findings thus suggest that verapamil may have potential utility as an adjunct to lithium. This effect may be mediated by additive actions on PKC inhibition, which may be an important mechanism for antimanic agents in general. [source] Evaluation of knowledge and anxiety level of patients visiting the colorectal pelvic floor clinicCOLORECTAL DISEASE, Issue 3 2006J. C. G. Coolen Abstract Objective, Discussing defaecating disorders is difficult for patients and many view anal physiology investigations (ultrasound, manometry, electromyography and pudendal nerve studies) as distasteful. This pilot study sought to assess whether present information sheets supplied to patients and the visit to the colorectal Pelvic Floor Clinic itself influenced patients' knowledge and anxiety. Patients and methods, Thirty Pelvic Floor Clinic patients from Auckland City Hospital were included. Each patient filled in a questionnaire before and after the clinic. This included objective questions about their knowledge of the structure and function of the pelvic floor and satisfaction with and understanding of the information sheet. Both visual analogue scale (VAS) and multiple choice questions (MCQ) were used. Their subjective and objective knowledge were compared. Anxiety was assessed on a visual analogue anxiety scale (VAAS). Results were expressed as VAS scores or percentage correct and relationships were tested using Fisher's Exact test and paired T -test. Results, Subjective knowledge increased in 93% of the patients. The doctor's explanation led to a greater increase in subjective knowledge than the information sheet (35/100 mm, P < 0.001 and 10/100 mm, P = 0.01, respectively). Subjective improvement in knowledge did not however, translate into an increase in objective knowledge (P = 0.63). The information sheet was read by 87% of the patients. The information sheet had reduced anxiety only in 23% of the patients and increased in 10%. Anxiety levels were not significantly influenced by the information sheet, but reduced significantly by the clinic visit in 87% of patients (P < 0.001). The mean anxiety level reduced from 44/100 to 12/100 after the clinic visit. Conclusion, Anxiety levels are high in those visiting the Pelvic Floor Clinic. It appears that it is the interaction with the doctor that has a profound influence on anxiety levels and subjective knowledge rather than written information. [source] Caterers' experiences and perceptions of implementing the 2006 school meal standardsJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 5 2008C.J. Weir Background:, School meal standards were introduced in 2006 (Department for Education and Skills) and caterers are expected to comply with these standards. No research has been conducted looking at the caterer's experiences and perceptions of implementing these standards. This area has 32 school meal provider organisations for 103 schools. Half the schools are with one provider and the others are, mostly, single-handed in-house operations, often managed by a local community member. The aim of the current study was to explore caterers' understanding of the school meal standards, the barriers to implementation, and proposed solutions, to inform local practice. Methods:, A combined quantitative and qualitative design was used. A questionnaire was used to assess understanding and implementation of the standards and distributed to all the catering provider organisations (n = 32), with a good response rate of 78% (n = 25). For each question about achievement of the ten food-based standards the responses were scored 0,4 where: 0 = ,Do not intend to achieve this standard'; to 4 = ,Fully achieved'. This gave a total standards achievement score for each catering provider organisation, where the minimum score that could be achieved was zero which indicated the minimum level of achievement and the maximum score which could be achieved was forty which indicated all ten standards fully achieved. Four focus group were undertaken involving 40 people who considered themselves to be in a management role within a catering provider organisation. Semi structured interviews were undertaken with 11 people (until saturation), using purposive sampling, to explore barriers and solutions to implementation of the standards in detail. Descriptive and appropriate inferential statistics (Fisher's Exact tests and independent samples t- tests) were performedon the datausingStatistical Package for Social Sciences (SPSS). The process undertaken for the qualitative analysis was thematic analysis, and used analytic hierarchy (Richie & Lewis, 2003). Approval for this study was obtained from Leeds Metropolitan University ethics committee. Results:, The qualitative discussions led to caterers' identifying two main themes. These were: support from various groups, and the roles and responsibilities caterers believed these groups had and should be performing in order to achieve successful implementation of the standards ,Think it's good someone's shaken up school meals but who is doing the actually work , it's us isn't it'.(Semi structured interview respondent medium primary provider) ,I've found it really difficult as I'm on my own at the school, totally on my own without anyone to help'. (Focus group participant primary school group). The groups that caterers identified as those who had roles and responsibilities and who should be providing support were the ,whole school'; catering provider organisations; parents; the local authority; and, the broader environment/whole population. Caterers felt the standards had ,gone too far too soon' and did not allow choice. Caterers felt finances were a barrier, and that training was required across all sectors to achieve success. The standards implementation achievement score were statistically higher for caterers who had received formal training compared with those with only food and hygiene (P = 0.001); and, between caterers who provided to a secondary school as opposed to a primary school only (P = 0.034). There was a statistically significant relationship between providers and qualifications with those providing to secondary schools more likely to have had formal qualifications (P = 0.015). Discussion:, Caterers felt all those involved in schools and school meals needed to undertake their roles and responsibilities, to provide support, and, to implement the ethos of a whole school approach. The caterers in this study identified many barriers and practical obstacles either experienced or perceived to implementing the new school meals standards. Conclusions:, The results will be used to inform the Local Authority and Primary Care Trust to ensure the effective implementation of the school meal standards. There may be opportunity to transfer these results to other school caterers, and to develop support and training to assist implementation. [source] Conservation genetics of the rare and endangered Leucopogon obtectus (Ericaceae)MOLECULAR ECOLOGY, Issue 10 2001G. Zawko Abstract Leucopogon obtectus Benth. is a declared rare species found in the kwongan vegetation in Western Australia. Plants on a mineral sand mine and the rehabilitation area are subject to disturbance. Genetic diversity was examined within and among all known populations using random amplified polymorphic DNA (RAPD) and amplified fragment length polymorphisms (AFLPs) for conservation. Both molecular markers revealed a high percentage (> 89%) of polymorphic markers and a high mean genetic distance among individuals (D = 0.3). Analysis of molecular variance showed that 86.7% (RAPD) and 89.7% (AFLP) of variability was partitioned among individuals within populations. Exact tests showed no significant population differentiation. The analyses indicated that L. obtectus exhibits high levels of genetic diversity despite small population sizes. The high levels of variability among individuals and the lack of clear population differentiation suggest that this species comprises a single, genetically diverse group. Conservation and management of L. obtectus should concentrate on maintaining the high levels of genetic variability through mixing genotypes and promoting outcrossing. [source] Comparison of bone marrow and peripheral blood ZAP-70 status examined by flow cytometric immunophenotyping in patients with chronic lymphocytic leukemiaCYTOMETRY, Issue 4 2006Rachel Sheridan Abstract Background: The mutational status of the immunoglobulin heavy chain variable gene in patients with chronic lymphocytic leukemia correlates with prognosis. Patients with mutated IgVH genes fare better than those with unmutated genes. Gene expression profiling studies identified the tyrosine kinase ZAP-70 to be expressed in unmutated CLL samples. Flow cytometric examination of ZAP-70 expression in tumor cells has been proposed to be a convenient surrogate marker for IgVH mutational status. However, a few studies have shown a small number of discordant results between ZAP-70 positivity, IgVH mutational status, and clinical outcome. There have been no reported studies comparing bone marrow samples with peripheral blood for ZAP-70 expression in CLL patients. Methods: We searched our flow cytometry files from October 2004 through April 2006 and identified CLL in 311 bone marrow and peripheral blood specimens from 256 patients. We defined ZAP-70 positivity as greater than 30% of the CD19+ B-cells above the isotype control value that coexpress ZAP-70. Statistical analyses were performed using the Fisher exact test and student t -test. Results: A significantly greater number of bone marrow specimens were positive for ZAP-70 when compared with the number of peripheral blood specimens. Of all the ZAP-70 negative specimens, CLL cells from bone marrow had a greater mean percentage of ZAP-70 positive cells when compared with the CLL cells from peripheral blood. Finally, six patients were identified who were ZAP-70 positive in the bone marrow but ZAP-70 negative in the peripheral blood. Conclusions: These results may be due to either an increase in the false positive rate in bone marrow specimens or to an intrinsic feature of CLL cells in the compartment that is biologically distinct from peripheral tumor cells. As prognosis and treatment decisions may be based on ZAP-70 results from either specimen type, it is prudent to further examine this observation. © 2006 International Society for Analytical Cytology [source] Efficacy of laser Doppler flowmetry for the diagnosis of revascularization of reimplanted immature dog teethDENTAL TRAUMATOLOGY, Issue 2 2001Kallaya Yanpiset Abstract , This study was performed to assess if laser Doppler flowmetry (LDF) is an improved method for the detection of revascularization of replanted teeth. Teeth were extracted and reimplanted under different experimental conditions. LDF readings were taken before extraction and weekly for 3 months. In control teeth, LDF baseline readings were taken and then repeated after the apical blood vessels were cut surgically. At the end of 3 months it was determined radiographically and histologically whether revascularization had occurred, i.e. vitality had returned. Results: LDF readings correctly predicted the pulp status (vital vs. non-vital) in 83.7% of the readings. 73.9% (17 of 23) were correct for the vital teeth and 95% (19 of 20) were correct for the non-vital teeth. Fisher's exact test (2-tail) indicated that there was no significant association between the efficacy of LDF and tooth type (P=0.166), although P2 was the least accurate tooth tested. Wilcoxon's matched-pair signed rank test demonstrated that in the revascularized (vital) teeth, the flux value between the baseline and week 2 dropped significantly (P=0.0001), increased significantly from week 2 to week 4 (P=0.0001) and then decreased steadily until week 12. However, at week 12 the flux was still significantly higher than at week 2 (P=0.010). In the teeth that failed to revascularize, the flux value dropped significantly by weeks 1 and 2 (P=0.004 and P=0.0001, respectively). Flux values did not increase from week 2. A Fast Fourier Transform (FFT) analysis confirmed a pulse of dominant frequency of 2 Hz in the teeth that returned to vitality and the lack thereof in those that stayed non-vital. One tooth in which the flux value evaluation indicated a non-vital tooth but the radiographic/histologic findings showed vital (false negative) possessed a pulse of dominant frequency and proved by this method to have successfully revascularized. [source] The Probability of Pulmonary Embolism Is a Function of the Diagnoses Considered Most Likely Before TestingACADEMIC EMERGENCY MEDICINE, Issue 4 2006Christopher Kabrhel MD Abstract Objectives: To determine the frequency of pulmonary embolism (PE) diagnosis when different alternative diagnoses were considered most likely before testing, because the relationship between specific alternative diagnoses and the diagnosis of PE has not been explored. Methods: This study was a preplanned secondary analysis of a prospective study of the diagnosis of pulmonary embolism conducted in the emergency department (ED) of an urban university hospital. Physicians were queried as to their most likely pretest diagnosis when they ordered any of the following tests to evaluate possible PE: D-dimer, contrast-enhanced computed tomography of the chest, ventilation,perfusion lung scan, or pulmonary angiogram. To compare the frequency of PE diagnosis across alternative diagnoses, risk ratios, 95% confidence intervals (CI), and p-values using Fisher's exact test were calculated. Results: Six hundred seven patients were enrolled, and 61 had PE. Physicians thought PE was the most likely pretest diagnosis in 162 (26.7%) patients, and 20.4% (95% CI = 14.4% to 27.4%) of these patients had PE. For four alternative diagnoses, PE was diagnosed less frequently than when PE was considered most likely: musculoskeletal pain (2.2%, 95% CI = 0.4% to 6.2%), anxiety (1.7%, 95% CI = 0.0 to 9.2%), asthma or chronic obstructive pulmonary disease (0, 95% CI = 0.0 to 10.9%), and viral syndrome (0, 95% CI = 0.0 to 14.3%). Conclusions: The frequency of PE is related to the most likely pretest alternative diagnosis. PE is diagnosed infrequently when anxiety, asthma or chronic obstructive pulmonary disease, musculoskeletal pain, or viral syndrome is the most likely alternative diagnosis. [source] Immunohistochemical expression of E-cadherin in sclerosing adenosis, ductal carcinoma in situ and invasive ductal carcinoma of the breastDIAGNOSTIC CYTOPATHOLOGY, Issue 4 2010Gil Facina M.D., Ph.D. Abstract E-cadherin (EC) is an important glycoprotein cell-adhesion molecule that appears to play a significant role in the progression of breast lesions. The objective of this study was to evaluate EC expression in sclerosing adenosis, ductal carcinoma in situ and invasive ductal carcinoma. Samples of breast lesions from 44 women were used in this study, comprising cases of sclerosing adenosis (n = 11), ductal carcinoma in situ (DCIS) (n = 10) and invasive ductal carcinoma (n = 23). Immunohistochemical evaluation of EC expression was assessed semiquantitatively and considered negative (<10% of cells with stained cytoplasmic membranes), positive+ (10,50% of cells stained) or positive++ (> 50% of cells stained). Fisher's exact test was used to compare the distribution of staining intensity in the lesions (P< 0.05). There was a progressive loss of EC expression from benign to malignant lesions. This difference was statistically significant when sclerosing adenosis was compared with DCIS (P < 0.0002), when sclerosing adenosis was compared with invasive ductal carcinoma (P < 0.008) and when DCIS was compared with invasive ductal carcinoma (P < 0.007). The present findings point to a significant association between reduced EC expression and the progression and aggressivity of breast lesions. Diagn. Cytopathol. 2010. © 2009 Wiley-Liss, Inc. [source] An increased proportion of inflammatory cells express tumor necrosis factor alpha in idiopathic achalasia of the esophagusDISEASES OF THE ESOPHAGUS, Issue 5 2009A. Kilic SUMMARY Achalasia is a motility disorder characterized by the absence of coordinated peristalsis and incomplete relaxation of the lower esophageal sphincter. The etiology remains unclear although dense inflammatory infiltrates within the myenteric plexus have been described. The nature of these infiltrating cells is unknown. The aim of this study was to evaluate the expression of proinflammatory cytokines , namely, tumor necrosis factor alpha and interleukin-2 , in the distal esophageal muscle in patients with achalasia. Lower esophageal sphincter muscle from eight patients undergoing myotomy or esophagectomy for achalasia of the esophagus were obtained at the time of surgery. Control specimens consisted of similar muscle taken from eight patients undergoing operation for cancer or Barrett's esophagus. The expression of tumor necrosis factor alpha and interleukin-2 were assessed by immunohistochemistry. The total number of inflammatory cells within the myenteric plexus were counted in five high power fields. The percentage of infiltrating cells expressing tumor necrosis factor alpha or interleukin-2 was calculated. Clinical data including demographics, preoperative lower esophageal sphincter pressure, duration of symptoms, and dysphagia score (1 = no dysphagia to 5 = dysphagia to saliva) were obtained through electronic medical records. Statistical comparisons between the groups were made using the unpaired t -test, Fisher's exact test, or Mann,Whitney U test, with a two-tailed P -value less than 0.05 being considered significant. The total number of inflammatory cells was found to be similar between the groups. A significantly higher proportion of inflammatory cells expressed tumor necrosis factor alpha in achalasia as compared with controls (22 vs. 11%; P= 0.02). A similar percentage of infiltrating cells expressed interleukin-2 (40 vs. 41%; P= 0.87). Age, gender, preoperative lower esophageal sphincter pressure, or dysphagia score were not correlated to expression of these cytokines. There was, however, a significant inverse correlation between duration of symptoms and the proportion of inflammatory cells expressing tumor necrosis factor alpha in achalasia (P= 0.007). In conclusion, a higher proportion of infiltrating inflammatory cells expressed tumor necrosis factor alpha in achalasia. Furthermore, this proportion appears to be highest early in the disease process. Further studies are required to more clearly delineate the role of tumor necrosis factor alpha in the pathogenesis of this idiopathic disease. [source] Critical reappraisal of current surveillance strategies for Barrett's esophagus: analysis of a large German Barrett's databaseDISEASES OF THE ESOPHAGUS, Issue 8 2008B. H. A. Von Rahden SUMMARY Endoscopic surveillance is recommended for patients with Barrett's esophagus (BE). Based on a large database, gathered from predominantly community-based practices in Germany, we aimed to investigate the time-course of malignant progression and apply these findings to current clinical practice. Data of 1438 patients with BE from a large German BE database were analyzed. Patients with at least one follow-up endoscopy/biopsy were included. Detection of ,malignant Barrett' (either high-grade intra-epithelial neoplasia or invasive adenocarcinoma) was considered as study end-point. Of 1438 patients with BE, 57 patients had low-grade intra-epithelial neoplasia (LG-IN) on initial biopsy and 1381 exhibited non-neoplastic BE. ,Malignant Barrett' was detected in 28 cases (1.9%) during a median follow-up period of 24 months (1,255), accounting for an incidence of 0.95% per patient year of follow-up. The frequency of ,malignant Barrett' was significantly higher (P < 0.001, ,2 -test) in the LG-IN group (n = 11, 19.3%) compared with the non-neoplastic BE group (n = 17, 1.2%). In the non-neoplastic BE group, ,malignant Barrett' was predominantly found during re-endoscopy within the first year of follow-up (12 of 17; 70.6%), in contrast to the LG-IN group, in which ,malignant Barrett' was observed predominantly after a time exceeding 12 months (8 of 11, 72.7%; P = 0.05, Fisher's exact test). Initial endoscopic evaluations seem to play the most crucial role in managing BE. After 1 year of follow-up, endoscopic surveillance should be focused on patients with LG-IN. In patients with repeatedly proven non-neoplastic BE, elongation of the follow-up intervals to the upper limit of current guidelines, that is, 5 years, might be justified. [source] Echocardiographic Features of Patients With Heart Failure Who May Benefit From Biventricular PacingECHOCARDIOGRAPHY, Issue 3 2003Amgad N. Makaryus Background: Recent studies suggest that cardiac resynchronization therapy through biventricular pacing (BVP) may be a promising new treatment for patients with advanced congestive heart failure (CHF). This method involves implantation of pacer leads into the right atrium (RA), right ventricle (RV), and coronary sinus (CS) in patients with ventricular dyssynchrony as evidenced by a bundle branch block pattern on electrocardiogram (ECG). Clinical trials are enrolling stable patients with ejection fractions (EF) , 35%, left ventricular end-diastolic diameters (LVIDd) , 54 mm, and QRS duration ,140 msec. We compared echocardiography features of these patients (group 1) with other patients with EF , 35%, LVIDd , 54 mm, and QRS < 140 msec (group 2 = presumably no dyssynchrony). Methods: Nine hundred fifty-one patients with CHF, LVID 54 mm, EF 35% by echocardiography were retrospectively evaluated. One hundred forty-five patients remained after those with primary valvular disease, prior pacing systems, or chronic atrial arrhythmias were excluded. From this group of 145 patients, a subset of 50 randomly selected patients were further studied (25 patients [7 females, 18 males] from group 1, and 25 patients [7 females, 18 males] from group 2). Mean age group 1 = 75 years old, mean age group 2 = 67 years old. Mean QRS group 1 = 161 msec, mean QRS group 2 = 110 msec. Each group was compared for presence of paradoxical septal motion, atrial and ventricular chamber sizes, LV mass, LVEF, and RV systolic function. Results: Of the initial group of 951 patients, 145 (15%) met inclusion criteria. In the substudy, 20/25 (80%) of group l and 7/25 (28%) of group 2 subjects had paradoxical septal motion on echo (Fisher's exact test, P = 0.0005). The t-tests performed on the other echocardiography variables demonstrated no differences in chamber size, function, or LV mass. Conclusions: Cardiac resynchronization therapy with BVP appears to target a relatively small population of our advanced CHF patients (15% or less). Although increasing QRS duration on ECG is associated with more frequent paradoxical septal motion on echo, it is not entirely predictive. Paradoxical septal motion on echo may therefore be more sensitive at identifying patients who respond to BVP. Further prospective studies are needed. (ECHOCARDIOGRAPHY, Volume 20, April 2003) [source] Therapeutic Yield and Outcomes of a Community Teaching Hospital Code Stroke ProtocolACADEMIC EMERGENCY MEDICINE, Issue 4 2004Andrew W. Asimos MD Objectives: To describe the experience of a community teaching hospital emergency department (ED) Code Stroke Protocol (CSP) for identifying acute ischemic stroke (AIS) patients and treating them with tissue plasminogen activator (tPA) and to compare outcome measures with those achieved in the National Institute of Neurological Disorders and Stroke (NINDS) trial. Methods: This study was a retrospective review from a hospital CSP registry. Results: Over a 56-month period, CSP activation occurred 255 times, with 24% (n= 60) of patients treated with intravenous (IV) tPA. The most common reasons for thrombolytic therapy exclusion were mild or rapidly improving symptoms in 37% (n= 64), intracerebral hemorrhage (ICH) in 23% (n= 39), and unconfirmed symptom onset time for 14% (n= 24) of patients. Within 36 hours of IV tPA treatment, 10% (NINDS = 6%) of patients (n= 6) sustained a symptomatic ICH (SICH). Three months after IV tPA treatment, 60% of patients had achieved an excellent neurologic outcome, based on a Barthel Index of ,95 (NINDS = 52%), while mortality measured 12% (NINDS = 17%). Among IV tPA-treated patients, those developing SICH were significantly older and had a significantly higher mean initial glucose value. Treatment protocol violations occurred in 32% of IV tPA-treated patients but were not significantly associated with SICH (Fisher's exact test). Conclusions: Over the study period, the CSP yielded approximately one IV tPA-treated patient for every four screened and, despite prevalent protocol violations, attained three-month functional outcomes equal to those achieved in the NINDS trial. For community teaching hospitals, ED-directed CSPs are a feasible and effective means to screen AIS patients for treatment with thrombolysis. [source] Comparing retention in treatment and mortality in people after initial entry to methadone and buprenorphine treatmentADDICTION, Issue 7 2009James Bell ABSTRACT Aim To compare retention in treatment and mortality among people entering methadone and buprenorphine treatment for opioid dependence. Data sources The Pharmaceutical Drugs of Abuse System (PHDAS) database records start- and end-dates of all episodes of methadone and buprenorphine treatment in New South Wales, and the National Death Index (NDI) records all reported deaths. Methods Data linkage study. First entrants to treatment between June 2002 and June 2006 were identified from the PHDAS database. Retention in treatment was compared between methadone and buprenorphine. Names were linked to the NDI database, and ,good matches' were identified. Deaths were classified as occurring during induction, maintenance and either post-methadone or post-buprenorphine, depending on the latest episode of treatment prior to death. The numbers of inductions into treatment, of total person-years spent in each treatment, and person-years post-methadone or buprenorphine, were calculated. Risk of death in different periods, and different treatments, was analysed using Poisson regression. Results A total of 5992 people entered their first episode of treatment,3349 (56%) on buprenorphine, 2643 on methadone. Median retention was significantly longer in methadone (271 days) than buprenorphine (40 days). During induction, the risk of death was lower for buprenorphine (relative risk = 0.114, 95% confidence interval = 0.002,0.938, P = 0.02, Fisher's exact test). Risk of death was lowest during treatment, significantly higher in the first 12 months after leaving both methadone and buprenorphine. Beyond 12 months after leaving treatment, risk of death was non-significantly higher than during treatment. Conclusions Buprenorphine was safer during induction. Despite shorter retention in treatment, buprenorphine maintenance was not associated with higher risk of death. [source] An analysis of cocaine powder in the Netherlands: content and health hazards due to adulterantsADDICTION, Issue 5 2009Tibor M. Brunt ABSTRACT Aims To report on trends in the content and adulterants present in street cocaine (powder) in the Netherlands and to describe the associated health hazards. Design and participants Drug consumers handed in samples of cocaine powder from 1999 to 2007 for analysis. Reports were compiled of users' experiences with the samples received. Measurements and analysis Linear regression analysis was used to assess the trend in adulterated cocaine powder across the study period, and comparison of reported adverse effects of adulterated with those of unadulterated cocaine by Fisher's exact test. Findings There has been a statistically significant upward trend in the occurrence of adulterated cocaine powder over the years. Adulterated cocaine was associated more frequently with reported adverse effects than unadulterated cocaine. Phenacetin, hydroxyzine and diltiazem appeared to be three adulterants contributing to these adverse effects. Conclusions An increase in adulterants was detected in the analysed cocaine powder between 1999 and 2007. This increase is associated with relatively more adverse effects with cocaine use. The cardiac and hallucinatory effects that were reported more frequently are not understood clearly. Adverse effects are likely to be due to several factors, including interactions of adulterants with cocaine and the route of administration. [source] Investigating moderate to severe paediatric trauma in the Auckland regionEMERGENCY MEDICINE AUSTRALASIA, Issue 2 2010Louise Couch Abstract Objective: To investigate differences between paediatric patients with moderate to severe trauma admitted from two paediatric ED, with respect to: demographics, patterns of presentation, mechanism of injury, injury severity scores (ISS), interventions and outcome. Method: Retrospective cohort study. Moderate to severe trauma was defined as ISS >9. Paediatric patients admitted to hospital via Starship Children's Emergency or KidzFirst ED, with trauma from 1 May 2003 to 30 April 2004, with ISS >9 were identified using multiple databases. The charts were reviewed and data collected included: demographics, hospital of first presentation, diagnoses, ISS, Paediatric trauma score (PTS), Glasgow coma score (GCS), ventilator hours, length of admission, survival and discharge destination. Descriptive statistics with 95% confidence intervals, Mann,Whitney U -test, ,2 -test and Fisher's exact test were used as appropriate. Results: A total of 393 children with moderate to severe trauma were identified using initial search strategies. Of these, 82 children met the inclusion and exclusion criteria for the study; 42 children were admitted via KidzFirst ED and 40 via Starship Children's ED. There was no statistically significant difference in ISS (P= 0.86), PTS (P= 0.11), GCS (P= 0.62), hours on a ventilator (P= 0.28) and length of stay (P= 0.87) between children admitted from Starship or KidzFirst ED. Conclusion: This study suggests that there are no differences in the numbers or severity of paediatric trauma patients admitted from the Starship and KidzFirst ED. This indicates triage is to the closest ED despite having a tertiary referral centre for paediatric trauma available in Auckland City. [source] Experience in adverse events detection in an emergency department: Nature of eventsEMERGENCY MEDICINE AUSTRALASIA, Issue 1 2007James Hendrie Abstract Objective:, The study was performed to determine the nature of adverse events in an ED. Methods:, The methodology has been described in the accompanying paper. Two by two tables were analysed using the two-tailed Fisher's exact test. A P -value of ,0.05 was considered significant. Statistical analysis was performed using MINITAB. Results:, One hundred and ninety-four events were detected, from a sample of 3222 patients. Except where specified, events with management causation ,3 were excluded. This excluded 24 events (12.4%) leaving 170 for analysis. Errors of commission occurred in 55% and omission in 45%. Errors of commission were significantly associated with prior events, errors of omission with ED events (P , 0.0001, respectively). The most common cause of events was drug reactions. 1.35% had a Naranjo score , 1, 0.54% , 4. Prior events were significantly associated with adverse drug reactions (P , 0.0001). Drug reactions were associated with a lower preventability score (P , 0.0001). Diagnostic issues were present in 1.2%. All three categories, that is diagnosis not considered, diagnosis within the differential and seriousness not appreciated were associated preventability ,4 (P , 0.0001, P , 0.02 and P , 0.004, respectively). Diagnostic problems were significantly associated with ED events (P , 0.0001). Conclusion:, In conclusion, the data demonstrate that events fall into two sets: prior events which are associated with errors of commission, drug reactions and lower preventability; and ED events which are associated with errors of omission, diagnostic issues and high preventability. [source] The structure of a local population of phytopathogenic Pseudomonas brassicacearum from agricultural soil indicates development under purifying selection pressureENVIRONMENTAL MICROBIOLOGY, Issue 3 2001Johannes Sikorski Among the isolates of a bacterial community from a soil sample taken from an agricultural plot in northern Germany, a population consisting of 119 strains was obtained that was identified by 16S rDNA sequencing and genomic fingerprinting as belonging to the recently described species Pseudomonas brassicacearum. Analysis of the population structure by allozyme electrophoresis (11 loci) and random amplified polymorphic DNA,polymerase chain reaction (RAPD,PCR; four primers) showed higher resolution with the latter method. Both methods indicated the presence of three lineages, one of which dominated strongly. Stochastic tests derived from the neutral theory of evolution (including Slatkin's exact test, Watterson's homozygosity test and the Tajima test) indicated that the population had developed under strong purifying selection pressure. The presence of strains clearly divergent from the majority of the population can be explained by in situ evolution or by influx of strains as a result of migration or both. Phytopathogenicity of a P. brassicacearum strain determined with tomato plants reached the level obtained with the type strain of the known pathogen Pseudomonas corrugata. The results show that a selective sweep was identified in a local population. Previously, a local selective sweep had not been seen in several populations of different bacterial species from a variety of environmental habitats. [source] Lag screw fixation of dorsal cortical stress fractures of the third metacarpal bone in 116 racehorsesEQUINE VETERINARY JOURNAL, Issue 7 2010S. L. JALIM Summary Reasons for performing study: The effectiveness and best method to manage dorsal cortical stress fractures is not clear. This study was performed to evaluate the success of lag screw fixation of such fractures in a population of Thoroughbred racehorses. Hypothesis: Lag screw fixation of dorsal cortical stress fractures is an effective surgical procedure allowing racehorses to return to their preoperative level of performance. Methods: The records of 116 racehorses (103 Thoroughbreds) admitted to Equine Medical Centre, California between 1986 and 2008 were assessed. Information obtained from medical records included subject details, limb(s) affected, fracture configuration, length of screw used in repair and presence of concurrent surgical procedures performed. Racing performance was evaluated relative to these factors using Fisher's exact test and nonparametric methods with a level of significance of P<0.05. Results: Of 92 Thoroughbred horses, 83% raced preoperatively and 83% raced post operatively, with 63% having ,5 starts. There was no statistically significant association between age, gender, limb affected, fracture configuration or presence of concurrent surgery and likelihood of racing post operatively or of having 5 or more starts. The mean earnings per start and the performance index for the 3 races following surgery were lower compared to the 3 races prior to surgery; however, 29 and 45% of horses either improved or did not change their earnings per start and performance index, respectively. Conclusions and potential relevance: Data show that lag screw fixation is successful at restoring ability to race in horses suffering from dorsal cortical stress fractures. [source] | ||||||||||||||||||||||||||||||||||||||||