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At least 127 records · Page 7Linked to original sources
PubMed2006

Predicting respiratory syncytial virus hospitalisation in Australian children.

BACKGROUND: There is limited information on respiratory syncytial virus infections among Australians, particularly those of Indigenous descent. AIM: This study identifies groups of infants at risk of hospitalisation with respiratory syncytial virus-positive lower respiratory tract infection who may be targeted for prevention with palivizumab. METHODS: Case control study: the case notes of 271 children with cases of respiratory syncytial virus-positive lower respiratory tract infection admitted to The Townsville Hospital were studied for risk factors. Controls were chosen randomly from babies born in The Townsville Hospital during that period. Multiple logistic regression analysis and classification and regression tree analysis were used to identify risk factors. RESULTS: Multiple logistic regression analysis identified birthweight <2500 g, maternal parity and marital status to be independent predictors of hospitalisation with respiratory syncytial virus-positive lower respiratory tract infection. Classification and regression tree analysis identified babies born weighing <2500 g who possessed older siblings to be at highest risk. Single mothers and smoking were additional risk factors. Indigenous babies were significantly more likely to be exposed to all of the identified risk factors. CONCLUSION: Babies born weighing <2500 g (especially with siblings) could be targeted for prevention. All Indigenous babies should be considered at high risk because of their exposure to multiple risk factors.

Adult↗
PubMed2005

Generalization of a prototype intelligent hybrid system for hard gelatin capsule formulation development.

The aim of this project was to expand a previously developed prototype expert network for use in the analysis of multiple biopharmaceutics classification system (BCS) class II drugs. The model drugs used were carbamazepine, chlorpropamide, diazepam, ibuprofen, ketoprofen, naproxen, and piroxicam. Recommended formulations were manufactured and tested for dissolution performance. A comprehensive training data set for the model drugs was developed and used to retrain the artificial neural network. The training and the system were validated based on the comparison of predicted and observed performance of the recommended formulations. The initial test of the system resulted in high error values, indicating poor prediction capabilities for drugs other than piroxicam. A new data set, containing 182 batches, was used for retraining. Ten percent of the test batches were used for cross-validation, resulting in models with R2 > or = 70%. The comparison of observed performance to the predicted performance found that the system predicted successfully. The hybrid network was generally able to predict the amount of drug dissolved within 5% for the model drugs. Through validation, the system was proven to be capable of designing formulations that met specific drug performance criteria. By including parameters to address wettability and the intrinsic dissolution characteristics of the drugs, the hybrid system was shown to be suitable for analysis of multiple BCS class II drugs.

Artificial Intelligence↗
PubMed2004

Effects of urbanization, economic development, and migration of workers on suicide mortality in Japan.

The relationships between male or female age-adjusted suicide mortality and social life factors for all 47 Japanese prefectures in 1980, 1985 and 1990 were investigated by stepwise multiple regression analysis after classification of 20 social life indicators by factor analysis. During this period, Japan experienced the second economic crisis (the so-called secondary oil crisis) in 1980-1983 and economic prosperity (bubble economy) in 1986-1990. In all the three years, male suicide mortality was significantly related inversely to the urbanization and economic development factor, the result of which was consistent with the data in our previous study for the years 1970 and 1975. Similarly, the male mortality was positively related to the factor of migration of workers in the three years. No factor significantly related to female mortality for all the three years was found. It is suggested that (1) urbanization was a major determinant which prevented male suicide mortality during the past 20 years (1970-1990) in Japan; (2) migration of workers became an important factor for male suicide mortality during these 10 years; and (3) female suicide mortality was less vulnerable to social life factors for these 20 years than the male mortality.

Adolescent↗
PubMed1997

The influence of socioeconomic status on health service utilisation by patients with AIDS in north Italy. The North-East Italian Group for Planning of AIDS Health Care.

Evidence for an association between socioeconomic status (SES) and health service utilisation (HSU) by patients with AIDS is examined using data for an Italian AIDS study population. A composite measure of SES which takes into account several key variables was developed using Multiple Correspondence Analysis. A classification of SES categories (high, medium-high, medium-low, low) was constructed and resource utilisation across the categories compared. The study population were patients with AIDS referred to 10 AIDS clinics in the study area in North-East Italy. A questionnaire survey was undertaken over the period January to June 1994, and was completed by 555 patients. Statistical analysis was conducted, using log-linear modelling, of health service utilisation (covering inpatient and day care) by SES categories, illness severity and HIV transmission route group. The analysis demonstrated that SES has a statistically significant association with variation in HSU, secondary in importance to severity of illness. This finding has important implications for future care planning for HIV/ AIDS in Italy, and potentially to other countries. Further research is needed to examine the relationship between SES and health service utilisation and costs in Italy and in other European countries.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Social life factors affecting suicide in Japanese men and women.

To clarify the social life factors affecting suicide mortality in Japanese men and women, the relationship between a wide variety of social and demographic indicators and age-adjusted suicide mortality was assessed in 46 prefectures in Japan by stepwise multiple-regression analysis after classification of the indicators by factor analysis. The findings indicated that rural residence was the major factor for male mortality in both 1970 and 1975; over the interval between these years, a serious economic crisis (the oil crisis) took place, and the mortality significantly increased. In addition, in 1970 (a time of high economic growth), home help for the elderly (a possible indicator of social isolation in old people), depopulation by social mobility, and urban residence were positively associated with male mortality. In women, on the other hand, both the 5-year increase in suicide mortality and the effects of the social life factors were less significant. The unique position of Japan in comparison with Western countries regarding social risk factors for suicide is discussed in the light of these findings.

Adolescent↗
PubMed2006

Does smoking influence the type of age related macular degeneration causing visual impairment?

AIMS: To assess the influence of smoking on the type of age related macular degeneration (AMD) lesion causing visual impairment in a large cohort of patients with AMD at a tertiary referral UK centre. METHODS: Prospective, observational, cross sectional study to analyse smoking data on 711 subjects, of western European origin, in relation to the type of AMD lesion present. Colour fundus photographs were graded according to a modified version of the international classification. Multiple logistic regression analysis was performed, adjusting for age and sex using the statistical package SPSS ver 9.0 for Windows. chi(2) tests were also used to assess pack year and ex-smoker data. RESULTS: 578 subjects were graded with neovascular AMD and 133 with non-neovascular AMD. There was no statistically significant association found between smoking status or increasing number of pack years and type of AMD lesion. The odds of "current smokers" compared to "non-smokers" developing neovascular rather than non-neovascular AMD when adjusted for age and sex was 1.88 (95% CI: 0.91 to 3.89; p = 0.09). CONCLUSIONS: Smoking is known to be a risk factor for AMD and this study suggests that smokers are at no more risk of developing neovascular than atrophic lesions.

Age Distribution↗
PubMed2004

Identifying spatial relationships in neural processing using a multiple classification approach.

The application of statistical classification methods to in vivo functional neuroimaging data makes it possible to explore spatial patterns in task-related changes in neural processing. Cluster analysis is one group of descriptive statistical procedures that can assist in identifying classes of brain regions that exhibit similar task-related functionality. In practice, a limitation of cluster analysis is that the performances of clustering algorithms rely on unknown characteristics of the data, making it difficult to determine which procedure best suits a particular analysis. We present a multiple classification approach that incorporates numerous algorithms, evaluates the associated classifications, and either selects a plausible partition relative to the others considered or pools the results from the numerous methods. The multiple classification approach utilizes a new performance criterion, called the relative information (RI) measure, to evaluate the quality of the candidate partitions and as the basis for producing a composite classification image. Employing multiple classifications, rather than a single algorithm, our methodology increases the chance of detecting the functional relationships within the data and, therefore, produces more reliable results. We apply our methodology to a PET study to explore spatial relationships in measured brain function associated with increasing blood alcohol concentration levels, and we perform a simulation study to evaluate the performance of RI.

Alcoholic Intoxication↗
PubMed1984

Comparative genetical analysis: a new tool for validating the schizophrenia subtypes.

350 carefully selected schizophrenic probands and their parents and siblings were diagnosed according to three different clinical classifications, and a multiple-threshold analysis was carried out within the framework of the multifactoral model of inheritance. The results suggest that of the three classification systems, Leonhard's and Sneshnevsky's nosological system delineates relatively homogeneous subtypes from the clinical and genetic point of view, pointing to the promise these nosological systems have for the planning of future research in psychiatric genetics.

Genetics, Behavioral↗
PubMed1999

[Profiles of 939 patients with obstructive sleep apnea syndrome treated with continuous positive pressure].

The aim of this study was to analyze the characteristics of patients on long-term continuous positive pressure therapy for obstructive sleep apnea in order to determine the efficacy, observance, tolerance, degree of patient satisfaction and patient quality of life using the Nottingham scale. A questionnaire was sent to 939 patients treated for at least six months in 11 centers. Factorial analysis of multiple correspondences and two classification analyses were used to establish patient profiles. Factorial analysis evidenced a relationship between patient satisfaction, reduced symptoms, observance and tolerance. The classification analyses distinguished three groups. Group A (n = 596) included primarily men (93%) who were satisfied with the treatment (99%) and showed good observance. Group B (n = 284) was characterized by patient satisfaction, observance, improved symptoms and lower quality of life than group A. Group C was composed of older patients who were satisfied with their treatment and showed good observance but who had no notable improvement in their symptoms. In conclusion, this study pointed out the difficulty in defining which patients with obstructive sleep apnea would benefit most from continuous positive pressure therapy. Good observance is not a sufficient criterion for therapeutic efficacy.

Adult↗
PubMed2006

Analysis of magnetic source localization of P300 using the multiple signal classification algorithm.

The authors studied the localization of P300 magnetic sources using the multiple signal classification (MUSIC) algorithm. Six healthy subjects (aged 24-34 years old) were investigated with 148-channel whole-head type magnetencephalography using an auditory oddball paradigm in passive mode. The authors also compared six stimulus combinations in order to find the optimal stimulus parameters for P300 magnetic field (P300m) in passive mode. Bilateral MUSIC peaks were located on the mesial temporal, superior temporal and parietal lobes. Interestingly, all MUSIC peaks in these regions emerged earlier in the right hemisphere than in the left hemisphere, suggesting that the right hemisphere has predominance over the left in the processing activity associated with P300m. There were no significant differences among the six stimulus combinations in evoking those P300m sources. The results of the present study suggest that the MUSIC algorithm could be a useful tool for analysis of the time-course of P300m.

Adult↗
PubMed2001

Are responses to therapy of metastasized malignant melanoma reflected by decreasing serum values of S100beta or melanoma inhibitory activity (MIA)?

In metastatic melanoma S100beta as well as melanoma inhibitory activity (MIA) are elevated in the serum in the majority of patients. Elevation has been found to correlate with shorter survival, and changes in these parameters in the serum during therapy were recently reported to predict therapeutic outcome in advanced disease. However, the value of these markers with respect to other possible markers by multivariate analysis has not yet been proven for individual patients. In this prospective study, S100beta and MIA were measured in the serum of 67 consecutive patients before and following treatment. Analysing both the sensitivity and the specificity of the serum parameters by the areas under the receiver operating characteristics (ROC) curves, decreases in S100beta and MIA during therapy were associated with response to therapy, while increases indicated progressive disease. Unexpectedly, the individual diagnostic value of changes in tumour markers during therapy was not superior to one-point measurements at restaging. Moreover, S100beta and MIA were not superior to the conventional parameters lactate dehydrogenase and C-reactive protein (CRP) on multiple logistic regression analysis. Applying classification and regression trees (CARTs), one-point measurements of CRP was shown to be the most relevant overall parameter.

Adult↗
PubMedDate not supplied

Ethical conflicts experienced by certified pediatric nurse practitioners in ambulatory settings.

INTRODUCTION: The purpose of this descriptive study was to (a) identify the types of ethical conflicts and their resolutions reported by a group of certified pediatric nurse practitioners (CPNPs) in their ambulatory practice and (b) to examine demographic, educational, and practice-setting factors associated with these conflicts. METHOD: Five hundred fifty-nine CPNPs, identified by the National Association of Pediatric Nurse Associates and Practitioners, received survey questionnaires in the mail and were asked to participate by describing an ethical conflict in their practice. Questionnaires were completed by 118 CPNPs. Each ethical conflict was analyzed according to a four content analysis classification system to capture multiple relevant meanings. The relationship between types of ethical conflicts and demographic, educational, and practice-setting variables was examined. RESULTS: One third (34%) of the perceived ethical conflicts fell in the child/parent/practitioner relationship category. Most conflicts (31%) were experienced as a moral dilemma where 2 or more clear moral principles apply but they support mutually inconsistent courses of action. Most ethical conflicts (22%) were unresolved. DISCUSSION: Understanding the nature of ethical conflicts that CPNPs are experiencing in ambulatory settings is important. Professional and institutions/agencies need to collaborate on how to initiate appropriate ethics education and consultation for professional staff to recognize, discuss, and resolve ethical conflicts in the workplace.

Adult↗
PubMed2003

Pseudomonas fluorescens mannitol 2-dehydrogenase and the family of polyol-specific long-chain dehydrogenases/reductases: sequence-based classification and analysis of structure-function relationships.

Multiple sequence alignment and analysis of evolutionary relationships have been used to characterize a family of polyol-specific long-chain dehydrogenases/reductases (PSLDRs). At the present time, 66 known and putative NAD(P)H-dependent oxidoreductases of mainly prokaryotic origin and between 357 and 544 amino acids in length constitute this family. The family is shown to include D-mannitol 2-dehydrogenase, D-mannonate 5-oxidoreductase, D-altronate 5-oxidoreductase, D-arabinitol 4-dehydrogenase, and D-mannitol-1-phosphate 5-dehydrogenase which form individual sub-families (defined by internal sequence identity of >/=30%) having distant origin and divergent substrate specificity but clearly displaying entire-chain relationship. When all forms are aligned, only three residues, Gly-33, Asp-230, and Lys-295 (in the numbering of Pseudomonas fluorescens D-mannitol 2-dehydrogenase (PsM2DH)) are strictly conserved. By combining sequence alignment with the known structure of PsM2DH and results from site-directed mutagenesis, we have developed a structure/function analysis for the family. Gly-33 is in the N-terminal coenzyme-binding domain and part of a nucleotide fingerprint region for the family, and Asp-230 and Lys-295 are at an interdomain segment contributing to the active site in which the lysine likely functions as the catalytic general acid/base. PSLDRs do not require a metal cofactor for activity and are specific for transferring the 4-pro-S hydrogen from NAD(P)H. Comparisons reveal that the core part of the two-domain fold has been conserved throughout all family members, perhaps reflecting the recruitment of a stable oxidoreductase structure and extensive trimming thereof to acquire functional properties specific to each sub-family. They also identify interactions that define the chemical mechanism of oxidoreduction and likely contribute to substrate and co-substrate specificities and are thus relevant for protein engineering.

Amino Acid Sequence↗
PubMed2006

Medial profrontal cortex and anterior cingulate cortex in the generation of alpha activity induced by transcendental meditation: a magnetoencephalographic study.

Previous EEG studies have shown that transcendental meditation (TM) increases frontal and central alpha activity. The present study was aimed at identifying the source of this alpha activity using magnetoencephalography (MEG) and electroencephalography (EEG) simultaneously on eight TM practitioners before, during, and after TM. The magnetic field potentials corresponding to TM-induced alpha activities on EEG recordings were extracted, and we attempted to localize the dipole sources using the multiple signal classification (MUSIC) algorithm, equivalent current dipole source analysis, and the multiple spatio-temporal dipole model. Since the dipoles were mapped to both the medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC), it is suggested that the mPFC and ACC play an important role in brain activity induced by TM.

Adult↗
PubMed2001

Analysis of MTR histograms in multiple sclerosis using principal components and multiple discriminant analysis.

Magnetization transfer ratio (MTR) histograms have the potential to characterize subtle diffuse changes in multiple sclerosis (MS) and other white matter disease. A new method is described which gives improved correlation with the Expanded Disability Status Scale (EDSS). Classification of individual subjects into normal and MS subgroups is shown. Principal component analysis (PCA) and multiple discriminant analysis (MDA) are shown to give results superior to methods of MTR histogram analysis using traditional features such as peak height and peak location. Scatterplots confirm the improved separation between groups achieved using the MDA score. The histogram analysis provides a comparison of two classification approaches, based on PCA and MDA, to recognize differences between normal controls and the four different subgroups of MS disease (and all MS patients). Multiple linear regression of these PCs vs. EDSS established an MR-based measure of disease. Using a central 60-mm slab of brain tissue, the success rate of binary classification between control and MS subgroups using MDA was 75-95%, depending on which two groups were being compared. Multiple regression analysis of EDSS with the first three PCs as independent variables was significant (r = 0.83 for secondary progressive MS, and r = 0.80 for all MS patients).

Brain↗
PubMedDate not supplied

[Pediatric cancer: analysis of hospital records].

OBJECTIVE: To analyze pediatric cancer hospital records regarding the occurrence of new cases; to verify the relation between sex, age, race, origin and the disease clinical extension; to describe the mortality of children with cancer; to explore the association of new cases with proposed demographic variables, disease clinical extension and vital status. METHODS: Observational, descriptive, longitudinal study in children up to 14 years old, from Santa Catarina. Three hundred and seventy-one new cases of cancer were treated in a regional reference outpatient clinic (1994-98) and recorded according to the International Classification of Childhood Cancer. Multiple Correspondence Analysis was applied to evaluate the categorical variables. RESULTS: Three-hundred and seventy-one new cases of cancer were recorded with constant distribution in each year. Cancer affected preschoolers (41.5%) and males (55.8%). Leukemia was observed in 36.6% of the cases. Non-localized stage on the diagnosis occurred in 55.7%. The death occurred in 55.7% of the cases with non-localized disease and 16.3% with localized disease. At the end of the study 58.8% of the children were alive. CONCLUSIONS: We observed more cases of cancer at pre-school age and among male subjects. Leukemia is the most frequent type of cancer. Non-localized disease predominates on the diagnosis. The death frequency is higher in the group with non-localized disease. There is direct association with non-localized disease, living vital status, school age, adolescent age, female, and for non-localized disease with death vital status, infant age, pre-school age and male.

English Abstract↗
PubMed1997

Attempt to establish a classification of patients suffering from coma and admitted to a hospital structure for short or medium term treatment: medical aspects and costs of hospital care.

We dispose of a database, constituted between 1987 and 1993, containing medical and cost information concerning 515 patients suffering from coma and admitted, after a period of resuscitation, to a French hospital establishment--Etablissement Hélio-Marin of Berck-sur-Mer (EHMB)--for short and medium term treatment, between 1974 and 1986. From this base, which contains demographic and clinical data (age, sex, condition upon admission, duration of consciousness disorders, Glasgow Outcome Scale (GOS) upon discharge) we devised a hierarchical classification analysis following a factorial analysis of multiple correspondences, on 2 sets: a sample of 515 patients (all causes of coma being merged) and a sample of 266 patients suffering from brain injuries. Four groups were determined for each typology. These groups were first described on the basis of the variables used for their construction, and later by considering other available variables: origin of coma, duration of stay at EHMB, future evolution of patients and cost of treatment (cost of specific care, average daily cost, total cost of hospitalization). Thus, typical clinical situations were identified in each classification, depending on age of patient, origin of coma and condition upon admission. These situations led to extremely different treatment costs (ratio from 1 to 5 in the general typology and 1 to 2.85 in the classification of brain injuries.

Adult↗