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At least 1,135 records · Page 63Linked to original sources
PubMed2004

Polymorphic changes in the KAL1 gene: not all of them should be classified as polymorphisms.

The KAL1 gene has a closely related nonfunctional pseudogene on the Y chromosome; a high degree of X-Y sequence similarity is observed. Some individuals present a T to C substitution at position 1833 (exon 12). Because this nucleotide differs in the X (thymine) and in the Y (cytosine) chromosome, we investigated if this was truly a polymorphism, or if in some cases the Y sequence had been amplified. The complete sequence of exon 12 of KAL1 was analyzed in 11 Kallmann Syndrome (KS) males, in 50 normal males, in 50 normal females, and in 16 patients with Ullrich-Turner Syndrome (UTS). Nucleotide 1833 was found in a heterozygous or a homozygous state in KS, normal males and normal females; UTS patients were always homozygous. Of the 61 males, 17 were heterozygous, while 11 were TT and 33 were CC. With these observations we can not assure whether these patients present a "real" polymorphism. Besides, all males were heterozygous in nucleotides 1678, 1694, 1699, 1708 and 1825, whilst females were homozygous; and in these positions, KAL1 also differs from its pseudogene. These results indicate that we are identifying the X and the Y nucleotide and these variants are not polymorphisms. Sequence variations may be pseudogene products rather than true polymorphisms, so we should always determine if the position where the variation is located differs between KAL1 and its pseudogene, because it has been suggested that the presence of various polymorphisms in affected individuals could be the cause of KS.

Adult↗
PubMedDate not supplied

Relations between serum levels of TSH, TBG, T4, T3, rT3 and various histologically classified chronic liver diseases.

Serum levels of TSH, thyroxine-binding globulin (TBG), T4, T3 and reverse T3 (rT3) were measured in 36 patients with fatty liver disease, 11 patients wih chronic persistent hepatitis, 17 patients with chronic active hepatitis, and 29 patients with liver cirrhosis. TBG was significantly above normal levels in both groups of chronic hepatitis, the slight concomitant T4 and T3 increase was significant only for T4 in chronic persistent hepatitis. A significant decrease in T4 and T3 concentration was found in fatty liver disease and in hepatic cirrhosis. A shift in T4 conversion to rT3 could exclusively be demonstrated for the group of hepatic cirrhosis, reflected by a significant increase in rT3. As our findings indicate normal TSH levels and a lack of clinical signs of hypothyroidism in chronic liver disease, the possibility of diverse regulating changes must be considered.

Alpha-Globulins↗
PubMed2002

Dimensional measures of psychopathology. The probability of being classified with a psychiatric disorder using empirically derived symptom scales.

OBJECTIVES: We sought to develop a ranking scheme that assigns a probability of having one of four psychiatric disorders to children based on their scores on a symptom scale. We then estimated the impact of each scale symptom on the prevalence of the disorder in the population. METHOD: Logistic regressions were specified for ADHD, ODD, depressive, and conduct disorders using all the individual symptoms in the pertinent scale as predictors. Individual fitted values from the regression function then served as a probability scale measure. We combined the prevalence and influence of each scale symptom to calculate its overall impact on the prevalence of the disorder. RESULTS: Probability distributions had a wide range of values and discriminated between cases and non-cases. Those having a disorder were consistently associated with higher probabilities in the scale. The estimated probability corresponds to the empiric prevalence of the diagnosis in a group of persons sharing the same estimated probabilities. Symptoms varied on their impact on the prevalence of the disorder. CONCLUSIONS: We recommend the estimated probability of the disorder based on the empirically defined scales as dimensional measures that complement prevalence of the disorder. Different symptoms are identified as targets for screening when selection is based on their impact on the prevalence of the disorder than when selection is based on the strength of the association with the disorder. We recommend using a common nosology with different classification schemes; the categorical definition of the disorder, the probability of having the disorder, and the impact of each symptom in the prevalence. Different measures serve different purposes.

Adolescent↗
PubMed2006

A statistical approach for classifying change in cognitive function in individuals following pharmacologic challenge: an example with alprazolam.

INTRODUCTION: The effects of any drug treatment on cognitive function are typically studied in groups of subjects. Observations made about the behavior of the drug, in the study sample, are then generalized to the population from which the sample was drawn. However, the magnitude and pharmacodynamic qualities of the response to many central nervous system-active drugs are known to vary in the population. Therefore, it is useful to consider statistical models for the detection of cognitive change in response to a drug treatment in individual subjects. MATERIALS AND METHODS: In this report, we first outline the statistical assumptions and requirements for the reliable estimation of clinically relevant individual change in cognition. We then used the sedative benzodiazepine, alprazolam, as a pharmacologic challenge in healthy volunteer subjects to test our statistical model, using a parallel groups placebo-controlled study design. After treatment, the nature and severity of alprazolam-induced cognitive change was determined for each individual. RESULTS: Our proposed method and analysis showed an excellent sensitivity and specificity for alprazolam-related cognitive deterioration in individuals. DISCUSSION AND CONCLUSIONS: These findings, although preliminary, suggest that statistically reliable decisions about the effects of sedative drugs on cognition can be made for individuals.

Adult↗
PubMed2005

Classifying wine according to geographical origin via quadrupole-based ICP-mass spectrometry measurements of boron isotope ratios.

The potential of quadrupole-based ICP-MS as a tool for B-isotopic analysis of wines and its usefulness in provenance determinations were assessed. A precision of 0.1-0.25% RSD (corresponding to a relative standard deviation of the mean of three replicate measurements of 0.06-0.12%) was sufficient to establish small differences in the B isotope ratios in wines from different geographical origins. Each sample measurement was bracketed by measurements of a standard and mass bias drift correction made by interpolation. Sample preparation was kept to a minimum to avoid possible fractionation. Dilution of the wine samples by a factor of 100 with 0.65% HNO3 was found to reduce matrix-induced mass discrimination substantially. Wines from three wine-producing regions, Stellenbosch, Robertson, and Swartland, in the Western Cape Province of South Africa, and wines from specific regions in France (Bergerac) and Italy (Valpolicella) were analyzed by ICP-QMS for their B-isotopic compositions. It was concluded that the 11B/10B ratios can be used to characterize wines from different geographical origins. Average 11B/10B ratios in red wines from South Africa (Stellenbosch), France (Bergerac), and Italy (Valpolicella) were found to differ by between 0.5 and 1.5%.

Boron↗
PubMed2000

Primary gastric B cell lymphoma: audit of 82 cases treated with surgery and classified according to the concept of mucosa-associated lymphoid tissue lymphoma.

There has been a trend toward stomach conservation during treatment for primary gastric lymphoma, but surgery ensures accurate pathologic diagnosis through the examination of resected specimens. A histopathologic classification for primary gastric lymphoma had been established with the knowledge that the low grade and high grade components occasionally coexist in a single lesion. Efficacy of this classification as an indicator of biologic behavior and prognosis was evaluated. The classification was performed by reexamining surgically resected specimens from 82 patients with stage IE and IIE gastric lymphoma. Clinical characteristics of the low grade and high grade lymphomas were then evaluated and the survival data analyzed. Despite the larger tumor diameter, the depth of invasion for the low grade type was mostly submucosal, and none had serosal invasion. In contrast, 50% of the high grade type had serosal involvement and were also found to have a higher incidence of node metastasis. Prognosis of the low grade type, a 10-year survival rate exceeding 90%, was significantly better than that of the high grade type. Multivariate analysis revealed that curability of the operation followed by the histopathologic grade were significant independent prognostic factors. Some characteristics of the low grade lymphoma were not consistent with what has been reported in the studies involving stomach-conserving strategies. Investigators are advised to note that the histopathologic grade determined with biopsy specimens alone could be misleading.

Adult↗
PubMed2000

Electrical impedance scanning for classifying suspicious breast lesions: first results.

It has long been established that cancer cells exhibit altered local dielectric properties compared with normal cells. Consequently, different electrical conductivity and capacitance are measurable in malignant vs normal tissues. In this study we evaluated the reliability of electrical impedance scanning (EIS), a new technology, for the classification of suspicious lesions: differentiating benign from malignant, and as a primary means of detection of breast cancer. Fifty-two women with 58 sonographically and/or mammographically suspicious findings were examined using electrical impedance scanning. Two different examination modes of TransScan TS2000 (Siemens, Erlangen, Germany), the standard-resolution mode for a routine overview examination, and the targeted high-resolution mode for a local examination of the suspicious lesion were used. All patients were additionally imaged by MR mammography (MRM) and underwent core-biopsy and/or surgical treatment after the EIS examination. With respect to the histopathological findings (29 malignant and 29 benign lesions) 27 of 29 (93.1%) malignant lesions were correctly identified using the high-resolution mode of EIS, whereas 19 of 29 (65.5%) benign lesions were correctly identified as benign (10 of 29 benign lesions showed as false-positive findings). Negative and positive predictive values of 90.5 and 73.0% were observed, respectively. Using the standard-resolution mode 22 of 29 malignancies were correctly detected (sensitivity 75.9%), whereas 22 of 29 were correctly identified as benign (specificity 72.4%). Electrical impedance scanning appears to be a promising new technology providing a relatively high sensitivity for the verification of suspicious mammographic and/or sonographic lesions especially using the high-resolution mode for local examinations. Artifacts, such as signals from superficial skin lesions, poor contact, and air bubbles, are currently a limitation.

Breast Neoplasms↗
PubMed2002

Classifying psychotic disorders: issues regarding categorial vs. dimensional approaches and time frame to assess symptoms.

The study's aims were to empirically derive classes of disorders and dimensional syndromes within psychotic disorders on the basis of the three time frames of symptom assessment and to comparatively examine their external validity. The level of concordance among classes and among dimensions across the time frames was generally low. The external correlates of psychopathological syndromes differed as a function of both type of assessment and the dimensional or categorical approach used. The dimensional approach was more effective than the categorical approach in predicting a set of clinical variables, irrespective of the time frame used to assess the symptoms. It is concluded that classification of psychotic disorders is highly dependent upon the time frame considered to assess symptoms and that dimensional classifications do have higher predictive power than categorical ones.

Adult↗
PubMed2004

A proposal for diagnostically meaningful criteria to classify increased epidermal growth factor receptor and c-erbB-2 gene copy numbers in gastric carcinoma, based on correlation of fluorescence in situ hybridization and immunohistochemical measurements.

Amplification of the epidermal growth factor receptor (EGFR) and/or c-erbB-2 oncogenes and overexpression of their proteins are detected in 30% of gastric carcinomas, but there are few reports regarding the correlation between gene amplification and protein overexpression. We examined the correlation between amplification of the EGFR and c-erbB-2 genes, detected using fluorescence in situ hybridization, and overexpression of their proteins, detected using immunohistochemistry, in formalin-fixed tissue sections of 54 surgically resected gastric carcinomas. A mean EGFR copy number per nucleus of four or more and an EGFR/chromosome 7 centromere (CEP7) ratio of 1.7 or more were each detected in 4 specimens (7%). The sensitivity and specificity of both criteria for EGFR protein overexpression were 75% and 92%, respectively. A mean c-erbB-2 copy number per nucleus of 7.0 or more and a c-erbB-2/chromosome 17 centromere (CEP17) ratio of 2.0 or more were detected in six (11%) and eight (15%) specimens, respectively. The sensitivity and specificity of the former criterion to c-erbB-2 overexpression were 83% and 98%, respectively, while those of the latter were 63% and 98%. A mean EGFR gene copy number of 4.0 or more and/or an EGFR/CEP7 ratio of 1.7 and a mean c-erbB-2 gene copy number of 7.0 or more and/or a c-erbB-2/CEP17 ratio of 2.0 or more would be useful in defining increased EGFR and c-erbB-2 gene copy numbers, respectively, in gastric carcinomas.

Adenocarcinoma↗
PubMed2006

Methods to classify familial relationships in the presence of laboratory errors, without parental data.

We consider the problem of accurate classification of family relationship in the presence of laboratory error without parental data. We first propose an adjusted version of the test statistic proposed by Ehm and Wagner based on the summation over a large number of genetics markers. We then propose use of the Bayes factor as a classification rule. We prove theoretically that the Bayes factor is the optimal classification rule in that the total classification error is minimized. We show via simulations that both the adjusted Ehm and Wagner method and Bayes factor classification rule reduce misclassification errors, and that the Bayes factor classification rule is robust against under-estimation or over-estimation of laboratory errors. For monozygotic twins versus dizygotic twins, the correct classification rate of the Bayes rule is over 99%. For full-siblings versus half-siblings, the Bayes factor classification rule generally outperforms Ehm and Wagner's method (in Am J Hum Genet 62:181-188, 1998), especially when full-sibling proportion is high.

Diagnostic Errors↗
PubMed2001

Computed tomography and magnetic resonance imaging of mild head injury--is it appropriate to classify patients with Glasgow Coma Scale score of 13 to 15 as "mild injury"?

OBJECTIVE: The purpose of this study is to examine the relation between Glasgow Coma Scale (GCS) score and findings on computed tomography (CT) and magnetic resonance (MR) imaging of patients with mild head injury presenting GCS scores between 13 and 15. METHODS: Data were collected from all consecutive patients with mild head injury who were referred to our hospital between July 1 and October 31, 1999. All patients were recommended to undergo CT and MR imaging examinations. Patients younger than 14 years of age were excluded. RESULTS: Ninety patients were recruited into this study. CT scans were obtained in 88 patients and MR imaging were obtained in 65 patients. Of these 90 patients, 2 patients scored 13 points, 5 scored 14 points and 83 (92.2%) 15 points. Patients with GCS score of 13 points demonstrated parenchymal lesions on both CT and MR imaging. Those with 14 points revealed absence of parenchymal abnormality on CT, but presence of parenchymal lesions on MR imaging. Patients in advanced age (chi square test, p<0.0001), and those with amnesia (p=0005, not significant), although scoring 15 points, revealed a tendency to abnormal intracranial lesions on CT scans. CONCLUSION: It is doubtful whether patients with GCS score 13 should be included in the mild head injury category, due to obvious brain damage on CT scans. MR imaging should be performed on patients with GCS score 14, since the parenchymal lesions are not clearly demonstrated on CT scans. Even if patients scored GCS 15, patients with amnesia or of advanced age should undergo CT scans at minimum, and MR imaging when available.

Adolescent↗
PubMed2026

A python based automated computational framework to classify and comparative genomics analysis of the global diversity of chili leaf curl virus (ChiLCV) strains to understand virus host interactions.

Chili leaf curl virus (ChiLCV) is a Begomovirus chillicapsici that is one of the most devastating viruses impacted on the production of chili in the world, especially in South Asia. In the present study, we combined high-throughput computational genomics with experimental analysis of global diversity. A workflow was created using automated Python scripts to download, curate and process ChiLCV genomes from public database. About 410 complete ChiLCV genomes download from public databases. Using a phylogenetic approach, these isolates were subdivided into 34 strains, belonging to 10 major clades, showing significant genetic diversity. Geographic analysis revealed that Pakistan (207 isolates) and India (148 isolates) were the main sources of ChiLCV diversity and the remainder of the isolates were from Oman, Bangladesh, Iran, Saudi Arabia and Sri Lanka. Recombination was observed as a major evolutionary force as more than twenty recombination events were detected. Analysis of cis-regulatory elements showed a complex structure of the viral promoter, including multiple binding sites for transcription factors, hormone-response elements, light-responsive elements, and stress-responsive elements, indicating a high number of interactions between viral regulatory elements and host signaling pathways. Pangenome analysis showed the presence of a highly dynamic open pangenome made up of strain-specific orthologous groups (species-specific orthogroups). Experimental inoculation of chili plants was also carried out to assess the biological effects of infection, along with phytochemical, FTIR, HPLC, and qPCR analyses.

Begomovirus↗
PubMed2002

Kappa statistics in the assessment of observer variation: the significance of multiple observers classifying ankle fractures.

Studies using kappa statistics have been conducted with a varied but limited number of observers. The aim of this study was to evaluate the significance of multiple observers on kappa as a measure of observer variation. One hundred orthopedic specialists were asked to assess a random sample of ten sets of standard radiographs of 94 consecutive patients with ankle fractures. The observers were randomly allocated into four groups, which again were divided into subgroups with an increasing number of observers. Random subgroups of three observers revealed kappa values from 0.20 to 0.64 in the Lauge-Hansen and 0.27 to 0.90 in the Weber classification system. With an increasing number of observers in the subgroups, kappa stabilizes around a mean value, indicating that the sampling variation and standard error decrease. The standard error found in this study makes kappa questionable as a measure for agreement among a small number of observers. Thus, kappa values obtained for a given diagnostic tool at one department are not directly comparable with results from other departments. We conclude that kappa cannot stand alone as a simple measure of observer variation.

Ankle Injuries↗
PubMed2005

The ratio between anterior abdominal wall surface/wall defect surface: a new parameter to classify abdominal incisional hernias.

Current classifications of incisional hernias are often not suitable. The aim of our study was to demonstrate that it is important to consider not only the wall defect surface (WDS) but also the total surface of the anterior abdominal wall (SAW) and the ratio between SAW/WDS). Twenty-three patients affected by > 10 cm size incisional hernias were examined for anthropometric analyses. The SAW, the WDS and the ratio SAW/WDS were calculated. All of the 23 patients were operated on 13 patients were treated with the Rives technique using a polypropylene mesh while the remaning ten patients had an intraperitoneal Parietex Composite mesh (PC). The two groups were compared for post-operative pain (with VAS) and intra-abdominal pressure (IAP) 48 h after the operation: bladder pressure, length of the procedure, average hospital stay and return to work were calculated. In the Rives group, WDS being equal, the higher IAP values were, the lower was the ratio SAW/WDS; furthermore, SAW/WDS ratio being equal, IAP values were low in cases where intraperitoneal mesh was used. Post-operative pain, measured with VAS, was critical when there was a low SAW/WDS ratio and a high IAP. In our experience, it is possible to predict a strong abdominal wall tension if the SAW/WDA ratio is below 15 mmHg. In these cases it is advisable to use a technique requiring the use of an intraperitoneal mesh. Our experience with PC was so positive that it is used in our department for all cases where an intraperitoneal mesh is required. At present, our proposal is that the SAW/WDS ratio is to be considered as a new parameter in current classifications of incisional hernias.

Abdominal Wall↗
PubMed2000

The predictive value of attributes of pain to classify rheumatoid arthritis.

Out of 2300 patients with rheumatic diseases 1627 were analysed to develop a classification of rheumatoid arthritis based on clinical attributes of pain. Of these, 641 patients had the disease and 986 were controls with other rheumatic conditions. For traditional format classification, six of eight variables were selected: pain at a fixed joint; symmetrical pain; continuous pain; pain mainly present at night or in the morning; pain following joint pressure; and pain decreased by load/movement. The occurrence of four or more of these features was associated with a 72.1% sensitivity and a 79.1% specificity. A classification tree constructed on four features that showed the greatest diagnostic power (symmetrical pain, pain mainly present at night or in the morning, pain at joint pressure, continuous pain), was associated with a 75.8% sensitivity and a 77.0% specificity.

Adult↗
PubMed2004

Defining and classifying syncope.

There is no widely adopted definition or classification of syncope and related disorders. This lack of uniformity harms patient care, research, and medical education. In this article, syncope is defined as a form of transient loss of consciousness (TLOC) due to cerebral hypoperfusion. Differences between syncope and other causes of TLOC such as epilepsy, and disorders mimicking TLOC are described. A pathophysiological classification of syncope is proposed.

Diagnosis, Differential↗