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At least 361 records · Page 20Linked to original sources
PubMed1992

Intermediate-term outcome after pulmonary balloon valvuloplasty: comparison with a matched surgical control group.

To assess late (4 to 5 years) gradient reduction after pulmonary balloon valvuloplasty in childhood, and to compare the effectiveness of valvuloplasty with that of surgical valvotomy, 20 valvuloplasty-treated children and their age- and gradient-matched surgical control patients underwent prospective, noninvasive evaluation. The average age at intervention was 4.3 +/- 1 years for the valvuloplasty group versus 4.7 +/- 0.8 years for the surgical control group (p = NS). Before intervention the peak systolic pulmonary stenosis gradient was 76 +/- 5 and 74 +/- 4.4 mm Hg for the valvuloplasty and surgery groups, respectively (p = NS). Late evaluation consisted of clinical examination, two-dimensional echocardiogram and Doppler study, 24-hour Holter monitoring, 12-lead electrocardiogram, exercise treadmill study and chest radiograph performed an average of 5.3 +/- 0.3 years after valvuloplasty and 11.7 +/- 0.5 years after surgery (p less than 0.01). The patients treated with balloon valvuloplasty had no evidence of restenosis; the residual pulmonary stenosis gradient at follow-up was 24 +/- 2.7 mm Hg (range 8 to 48) versus 35 +/- 3.6 mm Hg (range 19 to 70) immediately after valvuloplasty (p = NS). Comparison of the late residual gradients between treatment groups showed no hemodynamically significant difference (24 +/- 2.7 versus 16 +/- 1.5 mm Hg, balloon versus surgery; p less than 0.01). However, there was, a significant difference in the degree and severity of pulmonary valve insufficiency and ventricular ectopic activity between groups. In the balloon valvuloplasty group 11 patients had no pulmonary insufficiency, and the remaining 9 had mild insufficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed2005

Subjective quality of life of community living Sudanese psychiatric patients: comparison with family caregivers' impressions and control group.

BACKGROUND: Researchers have paid scant attention to comparative studies of quality of life (QOL) issues among psychiatric diagnostic groups; the studies of patient-caregiver concordance ratings had small sample sizes; and the reports are rare from the African and Arab worlds. OBJECTIVES: to assess the subjective QOL of stable Sudanese outpatients, using the WHOQOL-Bref, compared with a general population sample; examine the caregiver-patient concordance; and assess the variables that impact on domains of QOL. METHOD: The responses of outpatients with schizophrenia (99), major affective disorders (120) and neuroses (81) (mean age 33.8) were compared with 211 controls and the impression of their family caregivers. RESULTS: Patients were dissatisfied with life circumstances; the schizophrenia group and those with co-morbidity had significantly lower QOL scores; while the control group had higher QOL scores. There was no significant impact on QOL domains, of socio-demographic factors, duration of illness and treatment side effects. The schizophrenia group had least concordance with caregivers, but eight items were judged to be satisfactorily concordant for all groups. CONCLUSIONS: Psychiatric patients in stable condition can make reliable judgments of QOL, with relatives providing additional information. Differences in QOL and concordance of ratings reflect disease severity.

Caregivers↗
PubMed1978

Choosing control groups in the study of schizophrenic subtypes.

The choice of comparison groups in the study of schizophrenic subtypes is discussed. Current research rests upon the comparison of schizophrenic subtypes and controls unselected for the subtype characteristics used to divide the schizophrenics. One cannot infer, on the basis of this type of group comparison, whether subtype differences are specific to schizophrenia or reflect general personality and behavioral characteristics. It is suggested, therefore, that control groups be selected for their comparability to the schizophrenics on subtype characteristics.

Attention↗
PubMed1999

Assignment of Centers for Disease Control group IVc-2 to the genus Ralstonia as Ralstonia paucula sp. nov.

An integrated genotypic and phenotypic analysis of 12 Centers for Disease Control (CDC) group IVc-2 strains revealed that this taxon represents a novel species belonging to the genus Ralstonia. Comparative 16S rDNA sequence analysis allocated a representative CDC group IVc-2 strain to the Ralstonia branch of the beta subclass of the Proteobacteria. DNA-DNA hybridizations did not detect significant binding levels towards any presently known Ralstonia species, including Ralstonia pickettii. Its DNA base ratio is between 65 and 67 mol%. The name Ralstonia paucula sp. nov. is proposed, with strain LMG 3244 (= CDC E6793), isolated from a human respiratory tract, as the type strain. R. paucula can be differentiated from other Ralstonia species by whole-cell protein analysis, amplified rDNA restriction analysis and a variety of classical biochemical tests. Strains have been isolated from various human clinical and environmental sources.

Bacterial Proteins↗
PubMed1980

Comparison of lung cancer risks for dust workers, asbestos-cement workers and control groups.

In a prospective study, 1630 men exposed to dust for long periods (foundry workers and workers in metal, ceramics, glass, stone and other industries) and 1630 controls not exposed to dust were registered between the years 1950 and 1960; the population comprised workmen living in Vienna and born in 1910 or before. Controls were matched according to age and smoking habits. Causes of deaths were followed up to 1976 from official death certificates, mainly issued by hospitals with routine autopsy. General mortality was higher in the dust-exposed group, and there was a significant excess of deaths from lung cancer: 1.5 times higher than that for controls, 1.6 times higher than that for other Viennese men of the same age and 2.1 times higher than that for Austrian men. There were no excess deaths from lung cancer up to the age of 60. It is evident that only long exposure times raise the lung cancer risk for dust-exposed workers. In a historical prospective study of asbestos-cement workers and control groups, using the same criteria of sex, age and exposure time, the preliminary data show an age-standardized relative risk of 1.5 for asbestos-cement workers compared with cement workers, but no excess risk in comparison with the local and general population.

Age Factors↗
PubMed1989

Toward comprehensive management tailored to prognostic factors of patients with clinical stages I and II in Hodgkin's disease. The EORTC Lymphoma Group controlled clinical trials: 1964-1987.

From 1964 to 1987, the EORTC Lymphoma Group conducted four consecutive controlled clinical trials on clinical stages I and II Hodgkin's disease in which 1,579 patients were entered. From the onset the main aim of these trials was to identify the subsets of patients who could be treated safely by regional radiotherapy (RT). Therefore, several prognostic indicators were prospectively registered and progressively used in the trial protocols for the delineation of the favorable and unfavorable subgroups as soon as they were recognized of high predictive value. In the H2 trial (1972 to 1976), the histologic subtype was the only variable taken into account for the therapeutic strategy and the staging laparotomy findings were found to be of prognostic value only in patients with favorable prognostic indicators. In the H5 trial (1977 to 1982), patients were subdivided into two subgroups according to six prognostic indicators. Patients with favorable features were submitted to a staging laparotomy (lap); lap negative patients were randomized between mantle field RT and mantle field plus paraaortic RT. Disease free survival (DFS) and total survival (S) were similar in the two arms. Among patients with unfavorable features, DFS and S were significantly higher in the arm treated by combination of mechlorethamine, vincristine, procarbazine, prednisone (MOPP) chemotherapy (CT) and RT than in the arm treated by total nodal irradiation. Nevertheless, in patients below the age of 40, the overall survival rates were equivalent in the two arms. In the H6 trial, the delineation of the favorable subgroup was based on (a) absence of systemic symptoms and elevated ESR, (b) no more than one or two lymph node areas involved. The aim of the study was to assess the impact on survival of a therapeutic strategy including staging laparotomy. At a 4-year follow-up, no difference in survival was evidenced. In patients with unfavorable prognostic indicators, 3 MOPP-RT-3 MOPP were compared with 3 ABVD-RT-3 ABVD. From H1 to H5 trials, the proportion of patients having received CT during the course of the disease gradually decreased; the data suggest that a further reduction in the proportion of patients aggressively treated is conceptually possible. On the basis of the prognostic factors identified, one can delineate three subsets of patients and modulate toxic cost of the initial treatment according to the characteristics of these subsets. In the most favorable subgroup, RT alone produces high survival and CT is not justified.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1996

Polyphasic analysis of strains of the genus Capnocytophaga and Centers for Disease Control group DF-3.

A polyphasic approach was used to determine the relationships between well-characterized reference strains representing all seven Capnocytophaga species. One Centers for Disease Control (CDC) group DF-3 strain, a presumed relative of the genus Capnocytophaga, and 15 field isolates were included as well. Fourteen isolates were assigned to named Capnocytophaga species, all of which could be differentiated by means of whole-organism protein electrophoresis. A separate position was occupied by the CDC group DF-3 strain and by one field isolate representing a novel Capnocytophaga species. The phylogenetic position of each taxon was determined by means of 16S rRNA sequence analysis. A considerable genotypic heterogeneity within the genus Capnocytophaga was detected in spite of the minimal phenotypic differences. Comparative 16S rRNA sequence analysis revealed that CDC group DF-3 is not a close relative of the capnocytophagas but constitutes a separate genus that clusters together with Bacteroides forsythus and Bacteroides distasonis, two generically misclassified Bacteroides species. The degree of protein similarity correlated with our and published DNA-DNA binding values. Percentage 16S rRNA similarity values of greater than 97% did not guarantee conspecificity. All Capnocytophaga strains had very similar fatty acid contents characterized by significant amounts of 14:0, 15:0 iso (greater than 55%), 16:0, 16:0 3OH, and 17:0 iso 3OH. PCR-mediated DNA fingerprinting allowed discrimination of most species, although some strains could not be classified efficiently because of DNA polymorphisms.

Animals↗
PubMed1997

Occupational exposure to machining fluids and laryngeal cancer risk: contrasting results using two separate control groups.

This death certificate-based case-control study linked Connecticut Tumor Registry and Connecticut Division of Vital Statistics death data to determine whether machining fluid exposure is associated with laryngeal cancer risk. Laryngeal cancer cases were compared with oral cancer controls and general population controls. Level of exposure to machining fluids was imputed from the usual occupation and industry on the death certificate. Because exposure was infrequent among females, analysis was limited to males. When cases were compared to oral cancer controls, high exposure to machining fluids was associated with laryngeal cancer (odds ratio = 1.48; 95% confidence interval = 1.01-2.16), with a p-value for trend of 0.08. When cases were compared to population controls, no association between machining fluid exposure and laryngeal cancer was observed. A possible reason for the contrasting results, other than chance, is that exposure data quality for the cases and oral cancer controls may have differed from that of the population controls.

Case-Control Studies↗
PubMed1990

Age-related effects of placebo and active treatment in patients beyond the age of 60 years: the need for a proper control group.

The age-related response to placebo and active antihypertensive treatment was evaluated in 742 elderly hypertensive patients who were followed in the double-blind placebo-controlled trial conducted by the European Working Party on High blood pressure in the Elderly (EWPHE). In the two treatment groups, the fall in systolic and diastolic blood pressures after 3 months was negatively correlated with age (P less than 0.02), indicating that the hypotensive effect of placebo and active treatment was more pronounced in older patients. Further comparison of the two treatment groups failed to demonstrate any statistical differences in the slopes of the hypotensive effect on age. These conclusions were not altered by cumulative adjustments for baseline blood pressure, pulse rate, serum creatinine and the presence of cardiovascular complications at entry. In conclusion, in the present study, a similar blood-pressure-lowering action which increased with age was observed on active and placebo treatment; thus, proof that an observed age-related hypotensive effect is caused by a particular drug requires comparison with a control group on placebo.

Aged↗
PubMed1988

[The effect of posterior chamber lenses or YAG laser capsulotomy on sensitivity to glare and twilight vision in comparison to phakic control groups (corrected)].

Patients who had undergone extracapsular cataract extraction with implantation of a posterior chamber intraocular lens, and normal subjects of corresponding age and vision were examined with the mesoptometer and nyktometer to compare their twilight vision and glare sensitivity. All the results were poorer in patients with intraocular lenses. Statistically, some of the differences in the results of examinations performed in the two groups were highly significant. As the controls were strictly matched in age and visual acuity, these results confirm other studies with similar objectives. Additionally, some patients with posterior chamber lenses were examined who had also undergone YAG laser capsulotomy for secondary cataract. Although the number of cases was too small for statistical evaluation, it appeared that in this group twilight vision and glare sensitivity could not be improved in the same way as daylight visual acuity by means of this treatment. These findings indicate that since intraocular lenses are increasingly being implanted in younger patients, special attention should also be paid to scotopic vision and glare sensitivity during examinations for drivers' licenses, particularly in cases of good daylight vision. Special examinations, e.g., with the mesoptometer or nyktometer, should be carried out in all such cases. Increased glare sensitivity in eyes with lens implants should also be taken into consideration with regard to the increasing importance of computer and TV screens.

Adaptation, Ocular↗