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Neuropsychological stability and prognosis of subgroups of children with learning disabilities.

A sample of 74 Finnish children with mild learning disabilities (LD) and 57 controls was followed from the third grade (Study 1) to the sixth grade (Study 2). In the initial study, the sample had been grouped into five valid subgroups (Normal, General Language, Visuo-Motor, General Deficiency, Naming) utilizing a cluster analysis. In both studies a battery of 12 neuropsychological, reading, and writing tests was administered, and teacher ratings were obtained. The results indicated that the general neuropsychological profiles of the subgroups were maintained, but some changes, consistent with the progress in reading, were noted. The developmental rate of some neuropsychological functions from Study 1 to Study 2 in the subgroups of children with learning disabilities more closely approached that of the Normal subgroup. At follow-up, 64% of the original LD sample continued to have marked reading and/or writing problems. The Naming subgroup had a more unfavorable prognosis than the other subgroups, especially in reading, and the General Deficiency subgroup in writing (spelling), respectively. Some possibilities for using the results to improve remedial teaching are discussed.

Child↗

Neurometric subgroups in attentional and affective disorders and their association with pharmacotherapeutic outcome.

To determine if quantitative electrophysiologic measures correlate with pharmacotherapeutic response, we conducted a retrospective analysis of treatment outcomes in sequential patients with attention deficit disorder and affective disorders. One hundred medication-free patients meeting DSM-III-R criteria for attentional and affective disorders underwent pretreatment EEG, quantitative Neurometric EEG, and physical/laboratory examinations. Attention-disordered patients were first treated with a stimulant, secondarily with an antidepressant, and tertially with an anticonvulsant. Affectively disordered patients were treated initially with antidepressant, and secondarily augmented with anticonvulsant or lithium. Tertiary treatment was a stimulant. Patients were assessed up to 6 months. A Clinical Global Improvement score was assigned. Similar Neurometric subgroups were identified within both the attentional and the affectively disordered patients. Subgroups were relative alpha frequency excess, relative theta frequency excess, and/or inter-hemispheric hypercoherence. Without regard to DSM-III-R diagnosis, there were robust correlations between Neurometric subgroup membership, responsivity to selected pharmacologic agent class(es), and clinical outcome. The frontal alpha excess subgroup was 87% responsive to antidepressants. The frontal theta excess subgroup was 100% responsive to stimulants. The frontal alpha excess/hypercoherent subgroup was 85% or more responsive to anticonvulsants/lithium. The frontal theta excess/hypercoherent subgroup was 80% responsive to anticonvulsants. Patients with similar Neurometric features responded to the same class(es) of psychopharmacologic agent(s) despite their DSM-III-R classification.

Adolescent↗

Subgroups of patients with cancer with different symptom experiences and quality-of-life outcomes: a cluster analysis.

PURPOSE/OBJECTIVES: To identify subgroups of outpatients with cancer based on their experiences with the symptoms of fatigue, sleep disturbance, depression, and pain; to explore whether patients in the subgroups differed on selected demographic, disease, and treatment characteristics; and to determine whether patients in the subgroups differed on two important patient outcomes: functional status and quality of life (QOL). DESIGN: Descriptive, correlational study. SETTING: Four outpatient oncology practices in northern California. SAMPLE: 191 outpatients with cancer receiving active treatment. METHODS: Patients completed a demographic questionnaire, Karnofsky Performance Status scale, Lee Fatigue Scale, General Sleep Disturbance Scale, Center for Epidemiological Studies Depression Scale, Multidimensional Quality-of-Life Scale Cancer, and a numeric rating scale of worst pain intensity. Medical records were reviewed for disease and treatment information. Cluster analysis was used to identify patient subgroups based on patients symptom experiences. Differences in demographic, disease, and treatment characteristics as well as in outcomes were evaluated using analysis of variance and chi square analysis. MAIN RESEARCH VARIABLES: Subgroup membership, fatigue, sleep disturbance, depression, pain, functional status, and QOL. FINDINGS: Four relatively distinct patient subgroups were identified based on patients experiences with four highly prevalent and related symptoms. CONCLUSIONS: The subgroup of patients who reported low levels of all four symptoms reported the best functional status and QOL. IMPLICATIONS FOR NURSING: The findings from this study need to be replicated before definitive clinical practice recommendations can be made. Until that time, clinicians need to assess patients for the occurrence of multiple symptoms that may place them at increased risk for poorer outcomes.

Aged↗

Evidence for distinct pathomechanisms in genetic subgroups of chronic lymphocytic leukemia revealed by quantitative expression analysis of cell cycle, activation, and apoptosis-associated genes.

PURPOSE: In patients with chronic lymphocytic leukemia (CLL), the VH mutation status and genomic aberrations (13q-, +12q, 11q-, 17p-) identify distinct prognostic subgroups. The aim was to elucidate biologic mechanisms through which these genetic markers may exert their pathogenic influence. PATIENTS AND METHODS: Twenty-four genes involved in apoptosis, cell cycle, B-cell activation, and B-cell receptor (BCR) signaling were analyzed by real-time quantitative reverse transcription polymerase chain reaction (RQ-PCR) in 82 CLL cases constituting prototypic genetic CLL subgroups as defined by the VH mutation status and the genomic aberrations 13q-, +12, 11q-, and 17p-. RESULTS: The VH mutation subgroups were characterized by a differential expression of the BCR associated genes ZAP70 and PI3K. Among the subgroups defined by genomic aberrations, there was a deregulation of candidate genes from the affected critical genomic regions such as CDK4 (up), ATM (down), and TP53 (down) in the groups +12, 11q-, and 17p-, respectively. Additionally, the genomic subgroups were characterized by a significant deregulation of cell cycle and apoptosis regulators: AKT (up) in 13q, E2F1 (up) in +12, MYC (up) and BCL-2 (down) in 17p-, and CCND3 (down) in 11q- as well as 17p-. The 17p- subgroup showed an additional down-regulation of BCR-associated genes such as SYK and PI3K. CONCLUSION: The characteristic gene expression patterns observed implicate a differential regulation of cell cycle, apoptosis, and BCR signaling in the genetic subgroups illustrating distinct pathomechanisms and are evidence for a gene dosage effect being operative in CLL. These findings link the biologic diversity and clinical heterogeneity of CLL.

Apoptosis↗

Genomics identifies medulloblastoma subgroups that are enriched for specific genetic alterations.

PURPOSE: Traditional genetic approaches to identify gene mutations in cancer are expensive and laborious. Nonetheless, if we are to avoid rejecting effective molecular targeted therapies, we must test these drugs in patients whose tumors harbor mutations in the drug target. We hypothesized that gene expression profiling might be a more rapid and cost-effective method of identifying tumors that contain specific genetic abnormalities. MATERIALS AND METHODS: Gene expression profiles of 46 samples of medulloblastoma were generated using the U133av2 Affymetrix oligonucleotide array and validated using real-time reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry. Genetic abnormalities were confirmed using fluorescence in situ hybridization (FISH) and direct sequencing. RESULTS: Unsupervised analysis of gene expression profiles partitioned medulloblastomas into five distinct subgroups (subgroups A to E). Gene expression signatures that distinguished these subgroups predicted the presence of key molecular alterations that we subsequently confirmed by gene sequence analysis and FISH. Subgroup-specific abnormalities included mutations in the Wingless (WNT) pathway and deletion of chromosome 6 (subgroup B) and mutations in the Sonic Hedgehog (SHH) pathway (subgroup D). Real-time RT-PCR analysis of gene expression profiles was then used to predict accurately the presence of mutations in the WNT and SHH pathways in a separate group of 31 medulloblastomas. CONCLUSION: Genome-wide expression profiles can partition large tumor cohorts into subgroups that are enriched for specific genetic alterations. This approach may assist ultimately in the selection of patients for future clinical trials of molecular targeted therapies.

Adolescent↗

Psychiatric symptoms and HIV risk in MMPI-2 cluster subgroups of polysubstance abusers in treatment.

This-investigation identified personality subgroups based upon cluster analysis of MMPI-2 records of polysubstance abusers. Subgroups were compared on lifetime and current psychiatric symptoms and on attitudes and behaviors linked with HIV infection risk. High psychopathology, mild psychopathology, and subclinical MMPI-2 cluster types were identified which resemble those that have been identified in earlier studies with the original version of the MMPI. The High Psychopathology Subgroup had significantly higher proportions with all lifetime psychiatric problems (ASI), higher levels of all current psychiatric symptoms (SCL-90), and lower levels of confidence in ability to enact safer sexual practices than the Subclinical Cluster Subgroup. Fewer differences in lifetime and concurrent psychiatric symptoms were found in comparisons involving High Pathology and Mild Pathology cluster subgroups and Mild Psychopathology and Subclinical cluster subgroups. Those in the High Psychopathology Subgroup likely need treatment programs that address their more chronic and serious mental health problems and interventions that target their judgment and problem solving limitations that may increase HIV infection risk.

Adult↗

The effects of status on subgroup relations.

Two experiments were conducted to assess the impact of status differentials on subgroup attitudes and behaviours. In Experiment 1, 73 math-science students were led to believe they had higher or lower status than humanities students. They then performed a non-interactive decision-making task during which they were categorized exclusively as a university student (superordinate condition), or as a university student and math-science student simultaneously (subgroups condition). Experiment 2 (N = 98) differed from Experiment 1 in that perceptions of relative subgroup status were measured rather than manipulated. Consistent with social identity theory, subgroup members tended to categorize themselves more at the superordinate (university) level the lower status they considered their subgroup to be. In Experiment 2, a series of interactions also emerged, showing that status and inter-subgroup bias were positively related when the participants had been categorized exclusively at the superordinate level. When superordinate and subgroup identities were activated simultaneously, perceptions of status had no effect on levels of bias. The results were interpreted in terms of participants' needs for identity enhancement and identity distinctiveness.

Adolescent↗

Abnormal peripheral blood T-lymphocyte subsets in a subgroup of patients with COPD.

BACKGROUND: Smoking may induce changes in T-lymphocyte subsets in peripheral blood. Abnormalities of T-lymphocyte subsets in peripheral blood and in BAL fluid, and increased CD8+ T lymphocytes in the airways have been reported in patients with COPD. These findings suggest that T-lymphocyte abnormalities might be involved in the pathogenesis of airflow limitation in people who smoke. DESIGN: Cross-sectional study. SETTING: Outpatient pulmonary department of a university hospital. METHODS: To investigate this hypothesis, peripheral blood T-lymphocyte subsets were measured by flow cytometry using specific monoclonal antibodies in 20 healthy nonsmokers, 20 healthy smokers, and 20 smokers with stable COPD. No significant differences in the peripheral blood T-lymphocyte subsets were observed among the three groups. Because a previous study showed peripheral blood T-lymphocyte abnormalities in the subgroup of nonsmoking patients with COPD, we wanted to investigate what factors determine the subgroup of COPD with abnormal T-lymphocyte subsets. We tried to measure the relationship between T-lymphocyte subsets and physiologic indexes of pulmonary function tests in patients with COPD. The proportion of CD8+ T lymphocytes significantly correlated with diffusing capacity of the lung for carbon monoxide (DLCO) and DLCO per unit of alveolar volume (DLCO/VA), and CD4+/CD8+ ratio correlated with DLCO/VA. Therefore, we attempted to classify the patients with COPD into two subgroups on the basis of DLCO/VA: 10 COPD patients with low DLCO/VA (< 80% predicted) and 10 patients with normal DLCO/VA (> or = 80% predicted). RESULTS: The normal DLCO/VA subgroup had a significantly higher proportion of CD8+ T lymphocytes and a lower CD4+/CD8+ ratio than the healthy smokers or the low DLCO/VA subgroup. Moreover, FEV1/FVC significantly correlated with the CD4+/CD8+ ratio only in the normal DLCO/VA subgroup. CONCLUSION: These findings suggest that T-lymphocyte abnormalities might be involved in the pathogenesis of airflow limitation in a subgroup of patients with COPD, presumably with small airways disease, but not in all cases of COPD.

Aged↗

Asthma prevalence in Hispanic and Asian American ethnic subgroups: results from the California Healthy Kids Survey.

OBJECTIVES: Asthma prevalence for different ethnic groups in the United States, beyond white, black and Hispanic, is seldom reported. We compared the prevalence of asthma diagnosis among various Hispanic and Asian American ethnic subgroups using data collected from the school-based California Healthy Kids Survey. METHODS: The California Healthy Kids Survey was administered to 462 147 public school students in the seventh, ninth, and 11th grades throughout California during the 2001-2002 and 2002-2003 school years. Prevalence of lifetime asthma diagnosis was calculated for 11 Asian American Pacific Islander subgroups and 8 Hispanic subgroups. RESULTS: Asthma prevalence among Hispanic subgroups ranged from 13.2% for Mexican American students to 22.8% for Puerto Rican students and 23.0% among Cuban American students. Lifetime asthma diagnosis among the 11 Asian American Pacific Islander subgroups ranged from 10.9% among Korean American students to 23.8% among Filipino American students. CONCLUSIONS: The survey revealed substantial variation in asthma prevalence between the different Hispanic and Asian American Pacific Islander subgroups and that Pacific Islanders, Filipinos, Cubans, and Puerto Ricans are at elevated risk for asthma. Differences in the distributions of characteristics related to country of birth, residential history, generational status, and/or degree of acculturation might account for much of the observed differences in asthma prevalence between ethnic subgroups. Previous asthma prevalence estimates for Asians or Hispanics are in part a function of the particular ethnic composition of the population under investigation. We suggest that asthma studies that include a substantial number of Asian Pacific Islander and Hispanic persons use a more detailed categorization of race/ethnicity.

Adolescent↗

Functional dyspepsia: relationship between clinical subgroups and Helicobacter pylori status in Western Turkey.

The etiology of functional dyspepsia is not known. The objective of the present study was to determine the characteristics of functional dyspepsia in Western Turkey. We divided 900 patients with functional dyspepsia into three subgroups according to symptoms: ulcer-like (UL), 321 (35.6%), motility disorder-like (ML), 281 (31.2%), and the combination (C) of these symptoms, 298 (33.1%). All patients were submitted to endoscopic evaluation, with two biopsies taken from the cardia and corpus, and four from the antrum of the stomach. All biopsy samples were studied for Helicobacter pylori (Hp) density, chronic inflammation, activity, intestinal metaplasia, atrophy, and the presence of lymphoid aggregates by histological examination. One antral biopsy was used for the rapid urease test. Tissue cagA status was determined by PCR from an antral biopsy specimen by a random sampling method. We also determined the serum levels of tumor necrosis factor-alpha (TNF-alpha) and gastrin by the same method. Data were analyzed statistically by the Kolmogorov-Smirnov test and by analysis of variance. Hp and cagA positivity was significantly higher in the UL subgroup than in the others. The patients in the ML subgroup had the lowest Hp and cagA positivity and Hp density. The ML subgroup also showed the lowest level of Hp-induced inflammation among all subgroups. The serum levels of TNF-alpha and gastrin did not reveal any difference between groups. Our findings show a poor association of Hp with the ML subgroup of functional dyspepsia, but a stronger association with the UL and C subgroups.

Adult↗

Renin subgroups in essential hypertension.

A nomogram based on the relationship between plasma renin activity and urinary sodium excretion in normal subjects has been used to classify 956 patients with essential hypertension into low, medium and high renin subgroups. Patients with low renin hypertension (27 percent of all patients) were older (P less than 0.001) than patients with medium or normal renin hypertension. They also contained more women (P less than 0.01) and had higher systolic blood pressures than patients with medium renin hypertension. Creatinine clearance, albumin concentration and hematocrit were lower in low renin patients than in patients with medium renin activity. Serum potassium levels were lower, but urinary potassium excretion was higher in low renin patients. Most of the differences in clinical and biochemical parameters could be explained by the differences in age and male:female ratio between the subgroups. Despite lower renin values, aldosterone excretions were similar between the subgroups. Differences in renin activity and differences in aldosterone-renin ratio could not be explained by differences in age, duration of hypertension and sex ratios. Patients with low renin hypertension showed evidence of increased adrenal sensitivity to angiotensin II-induced aldosterone secretion. Patients with high renin hypertension (11 percent of all patients) were younger than patients with medium or normal renin hypertension. Other differences in biochemical characteristics between these renin subgroups included a slightly higher albumin concentration and hematocrit in patients with high renin levels. These differences and the difference in renin activity between patients with high and patients with medium renin essential hypertension could not be explained by differences in age and/or sex ratio between the two subgroups. Despite the higher renin activity, aldosterone excretion was similar between the high and medium renin subgroups. Therefore, patients in the high renin subgroup are characterized by signs of volume contraction and by a relative unresponsiveness of the adrenal gland to angiotensin II-induced aldosterone secretion. The possible role of these differences in the sensitivity of the adrenal gland in sustaining hypertension has yet to be defined.

Aldosterone↗

Response to wing-web challenge of Rous sarcoma virus subgroups in some chicken breeds.

Response to wing-web challenge (WWC) of Rous sarcoma virus (RSV) subgroups was studied in 4-8 weeks old chicks of a light breed, a heavy breed and a cross between an indigenous black plumage Bantam fowl and Australorp breed. Wing-web tumor (WWT) began to develop within one week in response to virus subgroups A (BS-RSV) and C [RSV (RAV-49)] challenge. In chicks challenged with subgroup D [RSV (RAV-50)] virus it took a minimum of 4 weeks for development of WWT. Positive response to WWC by subgroups A, C and D virus was 84%, 100% and 52%, respectively. The duration of exhibition of positive response was maximum for subgroup A virus, followed by subgroup D and minimum for subgroup C virus.

Animals↗

Clinical and epidemiological features of acute gastroenteritis caused by human rotavirus subgroups.

Rotavirus was detected in 44 (15.28%) of 288 hospitalised children suffering from gastroenteritis in Delhi over a period of one year. Of these 44 children, subgroup I and II rotaviruses were detected in 13 (29.55%) and 25 (56.82%) children respectively. Samples from 5 (11.36%) children did not react with either subgroup I or II monoclonal antibodies, indicating the presence of a third subgroup. Both subgroups I and II were detected in one (2.27%) case. The median ages of the children infected by subgroup I and II rotavirus were 7 and 12 months respectively. Rotavirus was more prevalent in boys than in girls. The peak of rotavirus infection was seen in the early winter months. The difference of maximum and minimum monthly temperatures correlated significantly (p less than 0.05) with the incidence of rotavirus infection. Subgroup II was the predominant group throughout the period of study and caused a significantly higher incidence of severe diarrhoea than did subgroup I.

Acute Disease↗

Dyspepsia and dyspepsia subgroups: a population-based study.

It has been proposed that patients with dyspepsia can be classified into symptom groupings that may represent different pathophysiological entities; however, it remains to be shown that distinct symptom subgroups exist. To estimate the prevalence of dyspepsia (defined as upper abdominal pain) and dyspepsia subgroups, an age- and sex-stratified random sample of Olmsted County, Minnesota, residents, aged 30-64 years, were mailed a valid self-report questionnaire; 82% responded (n = 835). Subgroups were as follows: those with symptoms suggestive of peptic ulceration (ulcerlike dyspepsia), those with gastric stasis (dysmotilitylike dyspepsia), those with gastroesophageal reflux (refluxlike dyspepsia), and the remainder (unspecified dyspepsia). Ulcerlike dyspepsia was the commonest subgroup (prevalence, 16.0/100; 95% confidence interval, 13.4-18.5), but 43% of subjects with dyspepsia could be classified into more than one subgroup. Nearly one third of dyspeptics also had irritable bowel symptoms, but these were not confined to any particular dyspepsia subgroup. Although dyspepsia is very common in the community and the majority have ulcerlike symptoms, there is such overlap among the dyspepsia subgroups that a classification based on symptoms alone in uninvestigated patients may not be useful.

Adolescent↗

[Different circulation patterns of subgroups A and B of human respiratory syncytial virus in some provinces of Cuba].

The nucleotide sequencing of the protein G C-terminal region of 37 samples taken from nasopharyngeal washings of under one-year old children from some Cuban provinces was made for 5 epidemic periods (1995-2000) to find out the circulation patterns of strains of human respiratory syncytial virus that is classified in two antigenic subgroups known as A and B; each of them contains multiple variants. Subgroup A has circulated during all these years but subgroup B was detected only in the year 2000. The presence of strains with two different sizes of protein G (297 aa and 298 aa) was observed whereas subgroup B showed only one size (295 aa). Phylogenetic analysis allowed identifying 5 and 2 genotypes within subgroups A and B respectively. Viruses present in Cuba were phylogenetically related to the strains of other parts of the world. Subgroup A comprised two strains very similar to Long prototype strain. Almost all the strains of both subgroups in the year 2000 phylogenetically related with strains that circulated in South Africa during the same period.

Base Sequence↗

Differential prognosis and utilization patterns among clinical subgroups of hospitalized geriatric patients.

While screening elderly inpatients on acute Veterans Administration (VA) hospital wards for a special geriatric program, we prospectively classified all patients age 65 and over, who had been hospitalized at least a week, into five clinical subgroups using specific diagnostic, prognostic, and functional criteria. These five subgroups were "geriatric evaluation unit (GEU) candidate", "severely demented", "medical", "terminal", and "independent". Medical record data from the initial admission and a full year of follow-up were collected from random samples of each subgroup and of nonscreened patients who had been hospitalized for less than a week. Analysis revealed that each subgroup had a distinctive pattern of survival, living location, and use of institutional services during the follow-up period. For one major subgroup ("GEU candidate"), a specific intervention (the GEU) has proved very effective in reducing mortality, increasing patient functioning, improving placement, and decreasing use of institutional services. Moreover, there are specific treatment and intervention strategies appropriate for each of the other subgroups (e.g., hospital-based home care, hospice, respite, and day treatment programs), although these services are not universally available nor clearly proved effective. The process of identifying patient subgroups illustrated in this study may be useful in needs assessment, in planning new intervention programs for frail elderly patients, and for identifying appropriate patients for these programs.

Aged↗

[The primary structure of a monoclonic immunoglobulin-L-chain of subgroup IV of the kappa type (Bence-Jones protein Len.)].

The complete amino acid sequence of Bence-Jones protein Len. was established by sequential analysis of tryptic and chymotryptic peptides. The result of these experiments and the comparative sequence analysis with the other 17 completely determined kappa-proteins is incompatible with the serological typisation of protein Len. as a member of subgroup II: There are 18 positions in protein Len. than cannot be associated with any one of the subgroups kappaI, kappaII or kappaIII. Also the average amino acid exchange rate between protein Len. and these subgroups is in the same range as the average amino acid exchange rate between these subgroups. Therefore Bence-Jones protein Len. is the first completely determined representative of a new IV. kappa-type subgroup. The variability of immunoglobulins follows a structural principle in which the single point mutations responsible for the variability are linked. The present paper contains the exact analysis of the linked point mutations within the so far best-investigated subgroup, kappaI (12 completely sequenced proteins). These linked exchanges allow the arrangement of the kappaI proteins in 4 subgroups and their further subdivision. The regularity of this amino acid sequence pattern can only be explained by an evolutionary origin of antibody variability. On the basis of this evolutionary mechanism the relationship of immunoglobulins can be depicted in a phylogenetic tree. Such a tree was therefore constructed for the 18 completely determined Bence-Jones proteins of kappa-type, for the first time taking into account Bence-Jones protein Len. Its topology is in complete agreement with the results of the comparative sequence analysis.

Amino Acid Sequence↗

Studies on group A (phage tail) bacteriocins of Serratia marcescens. V. Serological characterization of subgroup I and II bacteriocins.

Neutralization tests with rabbit hyperimmune sera revealed a close, if not identical, serological relationship among 7 group A (phage tail) bacteriocins of Serratia marcescens of subgroup I, and among 3 phage tail bacteriocins of subgroup II, respectively. On the other hand, subgroup I and II phage tail bacteriocins were found to be serologically unrelated, as determined with neutralization tests and Ouchterlony immunodiffusion experiments. Immunoelectrophoretic tests, employing a representive phage tail bacteriocin of each of the two subgroups, disclosed the electrophoretic mobility of bacteriocin no. 5 (subgroup I), whereas bacteriocin no. 16 (subgroup II) remained stationary. Thus, two additional differential criteria, i.e., differences in antigenicity and electrophoretic mobility, were obtained for the characterization of subgroup I and II group A (phage tail) bacteriocins of S. marcescens.

Animals↗