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PubMed1998

Direct evidence for suppression of recombination within two pericentric inversions in humans: a new sperm-FISH technique.

Crossover within a pericentric inversion produces reciprocal recombinant chromosomes that are duplicated/deficient for all chromatin distal to the breakpoints. In view of this fact, a new technique is presented for estimating the frequency of recombination within pericentric inversions. YAC probes were selected from within the q- and p-arm flanking regions of two human inversions, and two-color FISH analysis was performed on sperm from heterozygous inversion carriers. A total of 6,006 sperm were analyzed for chromosome 1 inversion (p31q12), and 3,168 were analyzed for chromosome 8 inversion (p23q22). Both inversions displayed suppression of crossing-over, although the amount of suppression differed between the two inversions. The recombination frequency of 13.1% recorded for chromosome 8 inversion was similar to the frequency of 11.4% previously estimated by the human/hamster-fusion method. For chromosome 1 inversion, the recombination frequency of 0. 4% reported here was below the limits of detection of the fusion technique. The simplicity of the FISH technique and the ease of scoring facilitate analysis of a sample-population size much larger than previously had been possible.

Animals↗
PubMed2006

Efficient in vitro system of homologous recombination in brome mosaic bromovirus.

Recent in vivo studies have revealed that the subgenomic promoter (sgp) in brome mosaic bromovirus (BMV) RNA3 supports frequent homologous recombination events (R. Wierzchoslawski, A. Dzianott, and J. Bujarski, J. Virol. 78:8552-8564, 2004). In this paper, we describe an sgp-driven in vitro system that supports efficient RNA3 crossovers. A 1:1 mixture of two (-)-sense RNA3 templates was copied with either a BMV replicase (RdRp) preparation or recombinant BMV protein 2a. The BMV replicase enzyme supported a lower recombination frequency than 2a, demonstrating a role of other viral and/or host factors. The described in vitro system will allow us to study the mechanism of homologous RNA recombination.

Bromovirus↗
PubMed1986

Meiotic recombination between two polymorphic restriction sites within the beta globin gene cluster.

Analysis of beta globin gene haplotypes for prenatal diagnosis of beta thalassaemia has revealed a recombination event within the beta globin gene cluster. Both a change in the AvaII polymorphic site within the beta globin gene and a change in the phenotype of the beta globin gene were observed. Paternity was established by the pedigree analysis of hypervariable 'minisatellite' DNA polymorphisms and the most probable explanation of the recombination event is a crossover between the psi beta globin gene and the beta globin gene. The data provide direct evidence in support of a DNA region 3' to the beta globin gene with a recombination frequency much higher than expected, and have important implications for the prenatal diagnosis of beta thalassaemia by linked restriction fragment length polymorphisms.

Alleles↗
PubMed1987

Nicardipine in the treatment of Raynaud's phenomenon: a randomized double-blind trial.

The efficacy of the calcium-channel blocker nicardipine in the treatment of Raynaud's phenomenon was assessed in a prospective, double-blind, randomized, crossover trial in 20 patients. Each patient received nicardipine 20 mg or placebo three times a day for two weeks and then was crossed over for two weeks. Nicardipine significantly decreased the frequency and severity of Raynaud's phenomenon as compared with placebo. The authors conclude that nicardipine is effective in the treatment of Raynaud's phenomenon.

Adolescent↗
PubMed1983

Dextromethorphan and codeine: objective assessment of antitussive activity in patients with chronic cough.

Dextromethorphan, the most widely used cough suppressant in the U.S.A., was compared with codeine, the traditional European antitussive, in a double-blind, crossover trial using both an objective and subjective assessment of efficacy in sixteen patients with chronic, stable cough. Both preparations, at a dose of 20 mg, were similarly effective in reducing cough frequency. Dextromethorphan lowered cough intensity to a greater degree than codeine (p less than 0.0008) and was considered the better antitussive by the majority of patients (p less than 0.001). In view of its lack of side-effects, its safety even in overdose and its non-narcotic status, the increasing trend in Europe to use dextromethorphan as a substitute for codeine in the treatment of cough is to be welcomed.

Adult↗
PubMed2002

A crossover, add-on trial of talampanel in patients with refractory partial seizures.

The authors report a double-blind, placebo-controlled, crossover study of talampanel in 49 patients with refractory partial seizures. Three doses of talampanel were investigated based on differences in patients' concomitant antiepileptic drug usage. Talampanel showed efficacy in reducing seizure frequency (p = 0.001) with a median seizure reduction of 21%. Eighty percent of patients had fewer seizures on talampanel than on placebo. Dizziness (52%) and ataxia (26%) were the only significant adverse events.

Adult↗
PubMed1999

Intranasal metoclopramide.

Intranasal metoclopramide is a new formulation of an established and effective antiemetic drug. Absorption after intranasal administration was lower than after oral or intravenous administration; otherwise the pharmacodynamic and pharmacokinetic profiles of the intranasal and parenteral formulations were similar. Intranasal and intramuscular metoclopramide showed similar efficacy in the control of acute emesis induced by moderately emetogenic chemotherapy in 12 patients. Intranasal metoclopramide 80mg significantly reduced the frequency of acute vomiting in 43 patients receiving highly emetogenic chemotherapy. A pilot study suggested that intranasal metoclopramide, with or without dexamethasone, may reduce cisplatin-induced delayed emesis. In a randomised crossover trial in 40 patients, intranasal metoclopramide or oral metoclopramide, both with dexamethasone, were equally effective in the control of delayed emesis induced by moderately-emetogenic chemotherapy. One 30 patient study suggests that intranasal metoclopramide has similar efficacy to oral metoclopramide in the treatment of functional dyspepsia. A non-significant trend to reducing postoperative nausea and vomiting has been seen in two trials of intranasal metoclopramide. Intranasal metoclopramide caused minor irritation of the nasal membrane and unpleasant taste in some patients, but was otherwise well tolerated. None of the more serious extrapyramidal effects sometimes associated with metoclopramide were reported.

Administration, Intranasal↗
PubMed1975

The treatment of cluster headaches with prednisone.

Nineteen patients obstinate with cluster headaches whose pain was not mitigated by standard treatment (Methysergide, caffeine, ergotamine preparation, phenobarbital and analgesics) underwent a double blind control study with single crossover for the evaluation of prednisone therapy. Compared to placebo, a single oral dose of prednisone in 17 cases produced sustained improvement. Maintenance administration of prednisone was also effective in decreasing the frequency of attacks; however a single dose of the steroid when headaches began was effective.

Adult↗
PubMed1987

Dog interaction with persons receiving institutional geriatric care.

A prospective study of 66 geriatric residents in 2 facilities was conducted to quantitate people-dog interactions. Residents were assigned randomly to sessions with dog activity and to sessions with other activity in a crossover design. This study involved a 12-week prestudy activity period and two 12-week activity periods, one before crossover and one after crossover. Systolic and diastolic blood pressures, psychologic evaluation of case histories, and other health and social variables were measured on all residents for dog activity and other combinations of programmed activity sessions. Frequence of attendance in both facilities was higher at dog activity sessions than at other activity sessions (P less than 0.01). Resident systolic blood pressures were lower in one facility during dog activity (P less than 0.02). Combined pre- and postactivity systolic and diastolic blood pressures at the same facility were lower when residents had 12 weeks of dog activity before 12 weeks of other activity (P less than 0.04). There were no significant differences in residents' blood pressures between measurements before and after dog activity (treatment mode) or between measurements before and after other activity. Psychologic scores of residents in both facilities were not significantly different between periods of the study. Of the 9 types of interaction between the residents and the dog, grooming and touching were the 2 most commonly used by residents.

Aged↗
PubMed1997

[Comparison of the place of origin of the referral of patients to hospital emergency service].

OBJECTIVES: To find the clinical and epidemiological differences in the place of origin (rural or urban) of patients attending a hospital Casualty Department (HCD) referred by a doctor. To detect problems in urgent non-hospital medical care, especially in rural areas. DESIGN: A descriptive crossover study. SETTING: "Centro" Health District, Sevilla. PARTICIPANTS: Patients referred to HCDs during 1995: Rural (R) = 3,521; Urban (U) = 13,203. MEASUREMENTS: The variables recorded for both groups were: age, sex, frequency of attendance, referral, diagnosis and destination of the patient. RESULTS: The urban population had a higher rate of attendance (131.8 visits per 1,000 inhabitants) than the rural (67.5). The percentage of referrals was greater from R (p < 0.001), although the proportion of population covered was similar. Age was similar, with more males from R. Abdominal and precordial pain and foreign bodies were the symptoms with most referrals from R; ear-ache, dizzy spells, minor surgery and fainting were from U. CONCLUSIONS: HCD is used to the same extent by R and U. More and better selected referred patients came from R. The rural doctor is the first to attend both serious and trivial pathology, whereas in the urban milieu the seriously ill patient goes straight to hospital.

Adolescent↗
PubMed2003

Low-frequency spin dynamics in the CeMIn5 materials.

We measure the spin lattice relaxation of the planar In(1) nuclei in the CeMIn5 materials, extract quantitative information about the low energy spin dynamics of the lattice of Ce moments in both CeRhIn5 and CeCoIn5, and identify a crossover in the normal state. Above a temperature T(*) the Ce lattice exhibits "Kondo gas" behavior characterized by local fluctuations of independently screened moments; below T(*) both systems exhibit a "Kondo liquid" regime in which interactions between the local moments contribute to the spin dynamics. Both the antiferromagnetic and superconducting ground states in these systems emerge from the Kondo liquid regime. Our analysis provides strong evidence for quantum criticality in CeCoIn5.

Journal Article↗
PubMed1989

Indices of severity of obstructive sleep apnea syndrome do not change during medroxyprogesterone acetate therapy.

Medroxyprogesterone acetate (MPA) could change the frequency and/or duration of disordered breathing events (DBEs) in patients with the obstructive sleep apnea (OSA) syndrome by altering pharyngeal muscle function relative to diaphragm and external intercostal function. Ten male patients with OSA syndrome underwent an initial polysomnogram with monitoring of EEG, EOG, myohyoid EMG, oral and nasal airflow, abdominal and thoracic movement, and SaO2. The patients were then entered into a randomized, double-blind crossover study using MPA, 150 mg/day, and MPA placebo. Each patient took tablets for one week and then had a second polysomnogram. After a three week washout, the patient again took tablets for a week prior to the third and final sleep study. There was no significant difference between drug and placebo for DBE time (expressed as a percentage of sleep time), DBE frequency, DBE mean duration or mean fall in O2 saturation during DBEs. We conclude that treatment with MPA does not alter indices of severity of the OSA syndrome.

Double-Blind Method↗
PubMed2005

Frequency of emergency room visits for childhood asthma in Ottawa, Canada: the role of weather.

The aim of this study was to evaluate associations between meteorological conditions and the number of emergency department visits for asthma in a children's hospital in Ottawa, Canada. A case-crossover study design was used. Hospital emergency department visits for asthma between 1992 and 2000 were identified based on patients' presenting complaints. We obtained hourly measures for the following meteorological variables: wind speed, temperature, atmospheric pressure, relative humidity, and visibility. Particular emphasis was placed on exploring the association between asthma visits and fog, thunderstorms, snow, and liquid and freezing forms of precipitation. In total, there were 18,970 asthma visits among children between 2 and 15 years of age. The number of visits and weather characteristics were grouped into 6 h case and control intervals. The occurrence of fog or liquid precipitation was associated with an increased number of asthma visits, while snow was associated with a reduced number (P<0.05). Stratified analyses by season found no association in any of the four calendar intervals between the number of asthma visits and visibility, change in relative humidity and change in temperature. In contrast, summertime thunderstorm activity was associated with an odds ratio of 1.35 (95% CI=1.02-1.77) relative to summer periods with no activity. Models that incorporate calendar and meteorological data may help emergency departments to more efficiently allocate resources needed to treat children presenting with respiratory distress.

Adolescent↗
PubMed1995

Improving fundamental frequency modulation in head trauma patients: a preliminary comparison of speech-language therapy conducted with and without IBM's Speech Viewer.

This study involves a preliminary comparison of traditional speech therapy for head trauma patients with therapy assisted by computer. Two subjects were treated in a 'crossover' design to compare the effects of each treatment. While both subjects improved, there was no obvious difference in treatment effectiveness. However, the computer support provided the measures of treatment efficacy which made this comparison possible.

Adult↗
PubMed1995

Effect of wheat bran in treatment of chronic nonorganic constipation. A double-blind controlled trial.

After a two-week basal period, 24 patients were randomly allocated to receive, with a crossover double-blind design, for two consecutive four-week periods, bran (20 g/24 hr) or placebo. The daily intake of water and dietary fibers was standardized. Symptomatology, oroanal transit time, bowel frequency, and stool weight were assessed in basal conditions and at week 4 and 8 of the treatment. Oroanal transit time decreased and bowel frequency and stool weight increased significantly during both bran and placebo administration in comparison with basal period. Bran treatment was more effective than placebo in improving bowel frequency and oroanal transit. During bran treatment oroanal transit time became normal only in patients with slow colonic transit and not in those with slow rectal transit. Neither the occurrence nor the severity of the most frequent accompanying symptoms of chronic constipation differed significantly between placebo and bran treatments.

Adolescent↗
PubMed1984

Treatment of resting tremor by beta-adrenergic blockade.

The effect of nadolol, a peripherally acting beta-adrenergic blocker, on resting tremor was examined in eight patients with idiopathic Parkinson's disease. With the use of a double-blind, placebo-controlled study of crossover design, patients received 80 to 320 mg of nadolol for 6 weeks while continuing their previous treatment regimen. Accelerometer readings showed a progressive reduction in tremor amplitude, but no change in tremor frequency, with increasing nadolol dosage. Maximum benefit was achieved at 240 mg, when resting tremor improved 50% (p less than 0.01). Physician ratings confirmed these findings. The results suggest that response to beta-adrenergic blockade may not be limited to postural or intention tremor and that such agents may not reliably differentiate between the tremor of Parkinson's disease and essential tremor.

Adrenergic beta-Antagonists↗
PubMed1986

Controlled double-blind trial of the clinical effect of nifedipine in the treatment of idiopathic Raynaud's phenomenon.

Twenty-six patients with idiopathic Raynaud's phenomenon participated in a double-blind, crossover clinical trial comparing the clinical effect of nifedipine with that of placebo. Four patients discontinued the study because of side effects and one patient defaulted at the return visit. Nifedipine significantly reduced frequency and severity of attacks (p less than 0.01). In an overall evaluation of drug effectiveness, 19 of 21 patients preferred nifedipine to placebo (p less than 0.01). Nifedipine proved to be effective in the treatment of idiopathic Raynaud's phenomenon, but side effects should be expected in some 30%.

Adult↗
PubMed1984

Parenteral penicillin epilepsy: tolerance to subsequent treatments.

We recorded spike activity induced by i.p. penicillin injections in eight rats, repeating the experiment five times per each rat, at 48-h intervals. Spike frequency was significantly reduced in all sessions subsequent to the first, without changes in penicillin blood concentrations. The penicillin model of epilepsy is therefore not advisable in studies on antiepileptic drugs with a crossover design.

Animals↗