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PubMed2004

Outcome of pregnancies in patients with anti-SSA/Ro antibodies: a study of 165 pregnancies, with special focus on electrocardiographic variations in the children and comparison with a control group.

OBJECTIVE: Aside from congenital heart block (CHB), sinus bradycardia and prolongation of the corrected QT (QTc) interval have been reported in infants born to mothers with anti-SSA antibodies. To assess the pathologic nature of these manifestations, this study focused on electrocardiographic (EKG) variations in these children, comparing them with findings in a control group. METHODS: We studied 165 consecutive pregnancies in 106 anti-SSA-positive women with connective tissue diseases (CTDs). EKGs obtained on 58 children of this group were compared with those obtained on 85 infants born to mothers with CTD who were negative for both anti-SSA and anti-SSB. RESULTS: No statistically significant difference was seen between the 2 study groups with regard to gestational age, prematurity, birth weight, age of the children at the time of EKG, age of the mothers, or treatments received by the mothers during their pregnancies. Seven of 137 children developed cutaneous neonatal lupus syndrome; 1 child developed CHB (CHB risk of 1 in 99 [1%] if only the first prospectively observed pregnancy in women without a history of CHB is included in the analysis). For EKGs recorded during the first 2 months of life, the mean +/- SD PR interval was 96 +/- 16 msec in the anti-SSA-positive group and 96 +/- 13 msec in the anti-SSA-negative group (P = 0.84), with mean QTc values of 397 +/- 27 and 395 +/- 25 msec (P = 0.57) and mean heart rates of 141 +/- 23 and 137 +/- 21 beats per minute (P = 0.20), respectively. No difference in the PR interval, QTc interval, or heart rate was observed for EKGs obtained between 2 and 4 months of life. When EKGs obtained at 0-2 months were compared with those obtained at 2-4 months, a physiologic prolongation of the QTc interval was observed in both study groups. No sudden infant death or symptomatic arrhythmia occurred during the first year of life. CONCLUSION: The EKG findings in children of anti-SSA-positive and anti-SSA-negative mothers were not significantly different. Our results suggest that the prolongation of the QTc interval and sinus bradycardia that have recently been reported in children of mothers with anti-SSA antibodies occur independently of the anti-SSA antibodies. The pathologic nature of these EKG variations was not confirmed by our controlled study.

Adult↗

PubMed1985

Z-transformed EEG power spectra of children with Down syndrome vs a control group.

Standardized EEG records of eighty-eight children with Down syndrome aged between six months and five years were analysed. The EEGs were digitalized, evaluated by spectral analysis, and subjected to z-transformation, a method which allows a direct comparison of the Down syndrome children with a normal control group (Munich Developmental Longitudinal Study). The results show a significant increase in absolute power, especially theta power; the absolute alpha power is less markedly increased or even decreased. The most significant differences, however, are observed when calculating the relative alpha power. Children with Down syndrome show a reduced relative alpha power already at the age of six months, and this reduction becomes even more prominent with growing age.

Child↗

PubMed2006

A novel erythrocyte-based immunoassay for simultaneous detection of both antimycobacterial antibody response and mycobacterial antigen in human serum samples of pulmonary tuberculosis and a control group of patients using 'a single probe'.

A modified passive hemagglutination using double aldehyde stabilized cells (tanned sheep erythrocytes treated with glutaraldehyde and pyruvic aldehyde) was evaluated for detection of both antimycobacterial antibodies and circulating mycobacterial antigens simultaneously in human serum samples from patients with pulmonary tuberculosis (n=40) and a control group (n=44). Double aldehyde stabilized cells sensitized with an optimum dose of 200 microg mL(-1) of sonicate extract of Mycobacterium tuberculosis antigens was used as single probe to detect both antibodies and antigen, respectively, by passive hemagglutination and passive hemagglutination inhibition. The sensitivity limit of passive hemagglutination inhibition was determined to be 280 ng mL(-1) using a dose-response curve. Sensitivity of passive hemagglutination and passive hemagglutination inhibition, respectively, was 90% and 52.5%, and specificity was 91% and 100%. Although passive hemagglutination and passive hemagglutination inhibition need further evaluation, these erythrocyte-based immunoassays are potentially advantageous, especially as double aldehyde stabilized sensitized cells could be used as a single probe for detection of both antibodies and antigen. In addition, erythrocyte-based immunoassays are rapid, simple and cost-effective with a high degree of sensitivity.

Animals↗

PubMed1990

[The stimulation of the rotation of the mandible with Angle Class II/1 and II/2 malocclusion with functional regulators and activators as compared to the control group].

In a teleradiological longitudinal study 86 patients with a Angle class II malocclusion were followed over a period of 4 years to examine the rotation of the mandible. 43 of these patients were treated with a functional regulator according to Fränkel, 22 with an activator and 21 children remained untreated (control group). As compared to the children in the activator group, the patients treated with the functional regulator (FR 1) showed that existing clockwise rotation was stimulated to the forward rotation and with the functional regulator (FR 2) a forward rotation was stopped.

Activator Appliances↗

PubMed1989

Using administrative data from Manitoba, Canada to study treatment outcomes: developing control groups and adjusting for case severity.

Administrative data are becoming increasingly available to health care researchers across North America and Europe. Such data sources are generally thought to be useful for documenting health care utilization. In this report, data from the provincial health insurance system in Manitoba, Canada are used to develop control groups and adjust for case severity. These are necessary prerequisites for using administrative data to study health care outcomes.

Data Collection↗

PubMed2003

Elevated risk for neonatal outcome following denial of pregnancy: results of a one-year prospective study compared with control groups.

AIMS: Newborns following denied pregnancies are delivered after either late onset or total absence of antenatal care, with a presumed subsequently increased risk for neonatal outcome. For this specific group, several characteristic outcome parameters are investigated. METHODS: During the period July 1, 1995 to June 30, 1996, a prospective case sampling was performed for denied pregnancies in Berlin. Besides determination of the parameters' frequency, comparison with two control groups is performed: a normal group (BBR, all Berlin deliveries in 1995) and a high risk group (VIR, all deliveries at a perinatal center in 1996). RESULTS: Altogether 69 neonates occurred. For gestational age < 37 weeks, birth weight < 2500 g, small for gestational age, transferal rate of newborns to neonatal unit and surgical delivery, a statistically significant worse outcome is demonstrated for denied pregnancies versus BBR and VIR (p-level < 0.05). Neonatal mortality is 5.8% in all cases, the corrected rate is 1.5% (excluding three non-viable cases of 21st and 23rd week of gestation). CONCLUSIONS: The data underline the elevated fetal outcome risk for newborns after denial of pregnancy. In this group, total absence or late onset of antenatal care results in a manifestation of pregnancy dependent risks. Preterm births and small for gestational age newborns, together with deaths, may be classified as at least potentially avoidable.

Adolescent↗

PubMed2005

Impact of a nurses' protocol-directed weaning procedure on outcomes in patients undergoing mechanical ventilation for longer than 48 hours: a prospective cohort study with a matched historical control group.

INTRODUCTION: The aim of the study was to determine whether the use of a nurses' protocol-directed weaning procedure, based on the French intensive care society (SRLF) consensus recommendations, was associated with reductions in the duration of mechanical ventilation and intensive care unit (ICU) length of stay in patients requiring more than 48 hours of mechanical ventilation. METHODS: This prospective study was conducted in a university hospital ICU from January 2002 through to February 2003. A total of 104 patients who had been ventilated for more than 48 hours and were weaned from mechanical ventilation using a nurses' protocol-directed procedure (cases) were compared with a 1:1 matched historical control group who underwent conventional physician-directed weaning (between 1999 and 2001). Duration of ventilation and length of ICU stay, rate of unsuccessful extubation and rate of ventilator-associated pneumonia were compared between cases and controls. RESULTS: The duration of mechanical ventilation (16.6 +/- 13 days versus 22.5 +/- 21 days; P = 0.02) and ICU length of stay (21.6 +/- 14.3 days versus 27.6 +/- 21.7 days; P = 0.02) were lower among patients who underwent the nurses' protocol-directed weaning than among control individuals. Ventilator-associated pneumonia, ventilator discontinuation failure rates and ICU mortality were similar between the two groups. DISCUSSION: Application of the nurses' protocol-directed weaning procedure described here is safe and promotes significant outcome benefits in patients who require more than 48 hours of mechanical ventilation.

Adult↗

PubMed1995

Comparison of Lp(a) concentrations and some potential effects in hemodialysis, CAPD, transplantation, and control groups, and review of the literature.

Apolipoprotein (a)-Lp(a)-is reported to be an independent risk factor for coronary artery disease and for hemodialysis (HD) access occlusion. Homology with plasminogen may predispose to thrombosis. High concentrations usually have been reported in patients on HD and on continuous ambulatory peritoneal dialysis (CAPD), but near-normal values in many kidney transplants (TP). We used Pharmacia immunoradiometric assay in 52 patients on HD, 58 on CAPD, 94 after TP, and 56 controls. The Lp(a) mean levels for CAPD, HD, TP, and control groups were 738, 647, 348, and 368 U/l and the medians were 542, 537, 96 and 143 U/l, respectively. The means and medians for CAPD and HD were significantly greater than those for TP and controls (p < 0.003 for means and < 0.005 for medians). We found no significant difference between: (1) Lp(a) means or medians comparing HD and CAPD or TP and controls; (2) Lp(a) means for the 33 patients with insulin-dependent diabetes mellitus and the 171 without; (3) number of occlusions of HD fistulae or grafts in patients with high Lp(a) values and without; (4) mean Lp(a) for CAPD patients on gemfibrozil and also for TP patients on 3-hydroxy-methylglutaryl coenzyme 1 reductase inhibitors, or diet alone, before and after treatment, and (5) mean Lp(a) values for HD and CAPD patients with and without myocardial infarction. Lp(a) did not correlate significantly with fractional shortening or left ventricular end systolic or diastolic diameter by echocardiogram or with ejection fraction. For TP patients, Lp(a) and serum creatinine correlated (p = 0.004), and mean Lp(a) for 71 TP on ciclosporin A exceeded that for the other 23 patients (p < 0.03). Lp(a) fell in 13 of 14 patients after TP (mean fall 77%). The dominant Apo(a) isoform in 10 of 13 patients on CAPD or HD with high Lp(a) values was the equivalent of S2 (Utermann). Lp(a) in HD or CAPD is often elevated and regulated by both genetic and renal failure factors, but falls after TP with return of renal function and mainly genetic regulation. Lp(a) was not a risk factor for coronary artery disease in HD or CAPD patients and did not fall significantly with two drugs or diet.

Adolescent↗

PubMed1990

[The possibility of stimulating mandibular growth in mandibular retrognathism with functional regulators and activators compared to a control group--a 6-year cephalometric longitudinal study].

In a teleradiological longitudinal study 86 patients with an Angle class II malocclusion were followed over a period of six years the development within the range of their facial skeleton. 43 of these patients were treated with a functional regulator according to Fränkel, 22 with an activator and 21 children remained untreated (control group). Compared with the activator-treated group, the group treated by regulators of function offered an improved development of the lower jaw.

Activator Appliances↗

PubMed1975

[Influence of efferent biliary ducts on the composition of bile acids. Studies on subjects with cholesterol gall stones and a stone-free control group].

Cadaveric livers and their gall bladders were used in order to determine the bile acids following separation by thin layer chromatography; spectrophotofluorimetry was employed. In the hepatic tissue of the lithiasis patients the bile acid concentrations and the ratio of the trihydroxycholanic acid (cholic acid) to the dihydroxycholanic acids (desoxycholic acid and chenodesoxycholic acid) are lower than in the control group. In the B-bile only cholic acid and the quotient cholic acid to chenodesoxycholic acid reveal any significant differences. Also, there exists an established positive correlation between the bile acid concentration in the hepatic tissue and in the B-bile of the alcoholic test persons but not in the cholelithiasis patients. From this we may infer that the concomitant inflammation of the gall bladder has an influence on the composition of the bile acids.

Autopsy↗

PubMed1993

Characterization of Centers for Disease Control group NO-1, a fastidious, nonoxidative, gram-negative organism associated with dog and cat bites.

Seventeen strains of fastidious, nonoxidative, gram-negative rods, isolated from human wounds resulting primarily from dog or cat bites, formed a distinct group, which was designated Centers for Disease Control (CDC) group nonoxidizer 1 (NO-1). The phenotypic characteristics of CDC group NO-1 were most similar to non-acid-producing Acinetobacter species, with the major difference being a negative reaction in the transformation assay test for Acinetobacter spp. The cellular fatty acid composition of CDC group NO-1 was different from those of Acinetobacter species and all other bacteria tested to date. The isolates were susceptible to a variety of antimicrobial agents including the aminoglycosides, beta-lactam antibiotics, tetracyclines, quinolones, and sulfonamides. Fifty percent of the isolates were resistant to trimethoprim. Ubiquinone-8 was present as the major isoprenoid quinone in CDC group NO-1.

Acinetobacter↗

PubMed1990

[8-MOP serum level profile following administration of Geroxalen to patients with psoriasis and a control group].

UNLABELLED: After 8-MOP application (Geroxalen) the mean serum levels with 11 single values over 8 hours from 21 psoriatics with squamous infiltrative plaques do not differ from serum level curves of 46 healthy volunteers (Psoriatics: maximum plasma level cmax 189 nm 8 MOP/ml serum at the time tmax 1,2h; area under the curve AUC0-8 284 ng.ml-1.h. CONTROL GROUP: cmax 193 ng 8 MOP/ml serum; tmax 0.9h; AUC0-8 290 ng.ml-1.h). A malabsorption of 8-MOP in psoriatic patients could not be found in our study, although this is described for fat among other.

Adult↗

PubMed1993

A multicentre comparative study of serum lipids and apolipoproteins in long-term users of DMPA and a control group of IUD users. World Health Organization. Task Force on Long-Acting Systemic Agents for Fertility Regulation Special Programme of Research, Development and Research Training in Human Reproduction.

A clinical trial was conducted in three centres to assess the effects of long-term use of the injectable contraceptive depot-medroxyprogesterone acetate (DMPA) on lipid metabolism. Fifty women who had used DMPA at a dose of 150 mg every three months for 3 to 9 years were recruited in Bangkok, Christchurch and Mexico City. They were compared to a control group of 120 IUD users. Total cholesterol, LDL-cholesterol, HDL-cholesterol, total triglycerides, apolipoproteins AI, AII and B were measured throughout one injection interval. Significant findings differed between centres. Compared to their own centre controls, DMPA users in Bangkok had higher LDL-cholesterol levels; those in Christchurch had lower HDL-cholesterol, apolipoprotein (apo) AI and apo AI/B ratio and higher apo B levels; those in Mexico City had a lower apo AI/B ratio. Further changes were observed during the injection interval, some of which were correlated to changes in serum MPA levels. It is concluded that long-term use of DMPA induces moderate changes in lipid metabolism which are unfavourable in terms of risk for atherosclerosis. This should be borne in mind when weighing the overall risks and benefits of this contraceptive method for a potential user.

Adult↗

PubMed1989

Spectrum of prostanoid release after bronchoalveolar allergen challenge in atopic asthmatics and in control groups. An alteration in the ratio of bronchoconstrictive to bronchoprotective mediators.

Prostanoids have been implicated in the pathogenesis of asthma because of their potential role in the modulation of airway tone. In the present study, the bronchoconstrictors prostaglandin D2 (PGD2) and thromboxane (TX), and those prostanoids able to protect against bronchoconstriction, prostaglandin E2 (PGE2), and the stable metabolite of prostacyclin, 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), were measured in bronchoalveolar lavage fluid (BALF) before and 5 min after endobronchial allergen challenge in four subject groups: nonatopic nonasthmatics (n = 6), nonatopic asthmatics (n = 3), atopic nonasthmatics (n = 9), and atopic asthmatics (n = 8). There were no significant differences in prechallenge prostanoid levels between the four groups, with the potentially bronchoprotective mediators present in highest concentration. Allergen challenge in atopic asthmatics resulted in significant increases (p less than 0.05) in PGD2 (97.4 +/- 19.4 to 1,053.2 +/- 338.6 pg/ml, mean +/- SEM) and TX (45.5 +/- 7.5 to 150.7 +/- 37.8 pg/ml) over prechallenge levels and control groups. Similarly, histamine increased in the atopic asthmatics after challenge (0.36 +/- 0.22 to 6.84 +/- 1.86 ng/ml; p less than 0.05). Atopic nonasthmatics had slight increases in PGD2 (96.9 +/- 25.4 to 219.7 +/- 47.5 pg/ml; p greater than 0.1) after challenge, whereas PGD2 and TX did not change in nonatopic subjects. A significant positive correlation was found between histamine, PGD2, and TX levels after challenge among all groups (p less than 0.001). There were no significant changes among the four groups after allergen challenge in 6-keto-PGF1 alpha or PGE2.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1990

Prophylactic effects of psychoanalysis on cancer-prone and coronary heart disease-prone probands, as compared with control groups and behaviour therapy groups.

It has been shown repeatedly that behaviour therapy fulfils a useful prophylactic function in the prevention of cancer and coronary heart disease. The present study investigates the effects of orthodox psychoanalytic treatment on the eventual probability of death from cancer and coronary heart disease in probands treated by psychoanalysis for over two years, probands who broke off psychoanalytic treatment after less than two years, and various control groups. Psychoanalysis is shown to have a significantly negative effect on survival after seven years follow-up.

Behavior Therapy↗

PubMed2004

Polymorphism of trinucleotide repeats in non-translated regions of SCA8 and SCA12 genes: allele distribution in a Polish control group.

Spinocerebellar ataxias are a group of neurodegenerative disorders caused by dynamic mutations of microsatellite repeats. Two novel forms of SCAs have been described recently: SCA8, with expansions of CTA/CTG repeats in 3'UTR of the SCA8 gene, and SCA12, caused by expansion of the CAG tract in 5'UTR of the SCA12/PP2R2B gene. Analysis of CTA/CTG and CAG polymorphism in those two genes was performed in a Polish control group consisting of 100 individuals without any neurological signs. The distribution and ranges of the number of non-pathogenic repeats were similar to those observed in other populations described previously. Expansion of CTA/CTG repeats in the SCA8 locus was found in 2 of 100 controls and in 5 probands among 150 pedigrees affected with unidentified ataxias. As such expanded alleles were also observed in their healthy relatives, the pathogenic role of expansions in the SCA8 gene remains uncertain.

3' Untranslated Regions↗

PubMed1997

Clinical trials: specific problems associated with the use of a placebo control group.

The topic of placebos in clinical research has been recently addressed in general medical journals, and is relevant to a clinical pharmacologists' readership as well. In this article we try to give an overview of the benefits as well as problems of this methodology. Although the use of placebos in drug development is frequently absolutely essential, important ethical and technical problems are generally involved. We conclude that the placebo-controlled trial although methodologically pure may sometimes cause too many difficulties in the clinical setting.

Control Groups↗

PubMed2001

Untreated short-term course of major depression: a meta-analysis of outcomes from studies using wait-list control groups.

INTRODUCTION: While the short-term response rates to antidepressant medication and placebo are well established, very little is known about the short-term course of untreated depression. Knowledge of the course of untreated depression can serve as a benchmark for assessing the true benefits of active treatment. METHOD: A meta-analysis was performed analyzing the outcomes of all psychotherapy studies that randomized adult outpatients with major depressive disorder to a wait-list control group. RESULTS: Nineteen studies involving 221 subjects were reviewed. The mean decrease in Hamilton Rating Scale for Depression scores over 2-20 weeks was 11.9%, while the mean decrease in Beck Depression Inventory scores was 15.7%. Using a subsample of studies that reported individual outcomes, we estimated that 15 of 76 subjects (19.7%) improved to a degree comparable to what would be considered a positive response in antidepressant trials. CONCLUSIONS: In the short-term, depressive symptomatology can be expected to decrease by about 10-15% on average without treatment. As many as 20% of subjects who participate in a short-term antidepressant trial may experience a spontaneous remission.

Adult↗