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PubMed1994

The Y Alu polymorphism in southern African populations and its relationship to other Y-specific polymorphisms.

Y-linked polymorphisms were studied in a number of African populations. The frequency of the alleles of a Y-specific Alu insertion polymorphism, termed the "Y Alu polymorphism," was determined in 889 individuals from 23 different African population groups. A trend in frequency was observed, with the insert largely absent in Caucasoid populations, at intermediate frequency in the Khoisan, and at high frequency in Negroids. The insert predates diversification of Homo sapiens, since it occurs in all groups. The Alu insertion is believed to result from a unique mutation event, and comparisons between this and several other Y-linked polymorphisms were carried out in an attempt to validate their usefulness in population and evolutionary studies. The p21A1/TaqI and pDP31/EcoRI polymorphisms and 49a/TaqI alleles were all shown to have arisen on more than one occasion, and evidence exists for a preraciation crossover event between the Y-linked pseudoautosomal XY275 locus and the Y chromosome pseudoautosomal boundary.

Africa, Southern↗
PubMed2005

Frequency and predictors of inappropriate management of recurrent gout attacks in a longitudinal study.

OBJECTIVE: To evaluate the patterns and determinants of medication use during recurrent gout attacks. METHODS: We followed participants with documented gout in an online prospective case-crossover study. During an attack, subjects were asked if they had consulted a physician for the attack and what medications they were using. Definitely inappropriate therapy was defined as use of allopurinol or a uricosuric agent acutely without having used it as a prophylactic. Potentially inappropriate therapy was defined as use of analgesics alone, alternative remedies, or no medications. We estimated the risk of having >or= 1 attack in 1 year using life table methods. We examined the relation of various risk factors to the risk of inappropriate therapy using Poisson regression. RESULTS: Among 232 participants (mean age 52 yrs, 81% male) with documented gout, the risk of having >or= 1 attack in a year was 69%. One hundred ten participants consulted a physician for each attack, 49 did so for only some attacks, while 43 never consulted a physician for any attack. Fifty-three participants had definitely (n = 10) or potentially (n = 43) inappropriate therapy for their recurrent attacks. Physician consultation for an attack was associated with increased risk of inappropriate therapy (risk ratio, RR, 2.5, p = 0.006), whereas an increasing number of gout attacks was associated with lower risk of inappropriate therapy (RR 0.8, p = 0.01). CONCLUSION: Given the high risk of recurrent attacks and the substantial number of persons whose attacks are not appropriately managed, further education about management of gout attacks for both patients and physicians may be warranted.

Adult↗
PubMed1977

Intra-HLA recombinations in juvenile diabetes mellitus.

Complete HLA and Bf typing of 18 families with juvenile diabetes mellitus (J.D.M.) showed that of 68 children, 9 bore recombinant haplotypes (13%). This frequency is significantly higher than the currently accepted 1.6% for intra-HLA recombinations with a p of 1.3 X 10(6) (binomial expansion) and may be related to the J.D.M. gene itself. Five of the nine crossovers were between HLA-A and B, and four between HLA-B and D. In one informative A/B recombination, Bf segregated with the HLA-B-D segment while in another two, it segregated in cis with HLA-A. This suggests the existence of two genetic sequences within the HLA region, one with Bf on the A site and a second one with Bf on the D site.

Adult↗
PubMed1982

Symptomatic treatment of benign prostatic obstruction with nicergoline: a placebo controlled clinical study and urodynamic evaluation.

A double-blind crossover study of the alpha-blocker Nicergoline was carried out in sixteen patients affected by benign prostatic bladder outflow obstruction. The "irritative" symptoms of prostatic hypertrophy, including nocturnal frequency and dysuria, were improved after Nicergoline significantly more than after placebo. In 10 further patients with prostatic hypertrophy, peak and mean flow rates increased by 50% and 77% respectively after the acute administration of Nicergoline. No side effects were detected. In conclusion Nicergoline seems to be active and well tolerated in the treatment of benign prostatic obstruction.

Adult↗
PubMed1978

Bacterial protoplast fusion: recombination in fused protoplasts of Streptomyces coelicolor.

Numerous recombinants arose when protoplasts of S. coelicolor were treated with polyethylene glycol and regenerated on non-selective solid medium. In six-factor crosses, recombination frequencies of more than 10% (up to 17%) were routinely observed. This recombination did not require either of the known sex factors, SCPI and SCP2. The proportion of multiple crossover classes was much higher than amongst recombinants produced by conjugated between mycelia. Analysis of the spatial distribution of crossovers in double and quadruple crossover recombinants showed only a slight tendency for crossovers to occur closer together than randomly on the complete linkage group. This suggests that genomes brought together by protoplast fusion are complete, or nearly so (in conjugation, in contrast, one genome is represented by a comparatively short fragment). Individual colonies arising from fused protoplasts did not contain different parental genomes without recombinants, but recombinants often occurred without parentals. Several recombinant genotypes often occurred in the same colony, showing a segregation of some, only, of the parental alleles. Complementary genotypes, parental or recombinant, did not occur in the same colony. It is postulated that complete genomes of fused protoplasts usually become fragmented and that crossing-over, often repeated, occurs between the fragments, to generate haploid recombinants. Analysis of fusions between propoplasts of four different genotypes indicated that the average number of protoplasts fusing together was low, but nevertheless appreciable numbers of fusions involved three or four genomes. Crossing-over between them produced recombinants inheriting markers from three or four parents. The generation of nearly random populations of recombinants between two or more parent strains by propoplast fusion under the conditions described appears to have simple applications in industrial and academic strain construction.

Chromosomes, Bacterial↗
PubMed1993

Effects of antihypertensive drugs atenolol and nifedipine on sexual function in older men: a placebo-controlled, crossover study.

Investigated the adverse sexual effects of two antihypertensive drugs, atenolol and slow-release nifedipine, in a placebo-controlled, randomized, crossover study. Subjects were 16 older men (mean age = 66.6 years, SEM = 1.4) with mild to moderate hypertension. Subjects completed daily self-reports on 13 measures of sexuality: frequency of desire, coitus, noncoital partner sex, masturbation, morning erections, spontaneous erections, orgasms in coitus and masturbation, firmness of morning, masturbatory and coital erections, and subjective pleasure in coitus and masturbation. Except for a significant decrease in masturbatory erectile firmness with nifedipine therapy, variables did not differ between the two drug treatments or between either drug and placebo. Although the sample was relatively small, small differences between treatment means suggest that these antihypertensive agents are fairly benign relative to sexual function in men.

Aged↗
PubMed2004

Efficacy and safety performance of the Innovo insulin doser.

Innovo (Novo Nordisk A/S, Hillerød, Denmark) is a new insulin injection system that offers built-in memory and a large, clear display to provide patients with more control during insulin injections. The aim of this trial was to compare the efficacy and safety of Innovo and NovoPen 3 (Novo Nordisk A/S) in patients experienced in using insulin injection devices. Participants included 217 adults who had used NovoPen 3 or other durable pen systems for at least 6 months. This multinational, multicenter, open, randomized crossover trial comprised two treatment periods of equal duration (6 or 12 weeks). Efficacy was determined using hemoglobin A1c (HbA1c) and blood glucose concentrations, and safety parameters were the frequency and severity of hypoglycemic events. Daily insulin dose was also recorded. The effect of device type on change in HbA1c was not significant. The adjusted treatment differences between Innovo and NovoPen 3 were 0.088% [confidence interval (CI), -0.031 to 0.208%] and 0.005% (CI, -0.086 to 0.096%) for the German and Dutch/Austrian sites, respectively. Blood glucose profiles were not affected significantly by device type. Treatment differences were 0.04 mmol/L (CI, -0.57 to 0.48 mmol/L) and 0.21 mmol/L (CI, -0.13 to 0.55 mmol/L) for the German and Dutch/Austrian sites, respectively. Innovo and NovoPen 3 did not differ with regard to safety: There were no differences in numbers of various types of adverse events, or in percentage of patients experiencing one or more hypoglycemic event. This study demonstrates that the Innovo insulin doser is as safe and efficacious as NovoPen 3.

Adult↗
PubMed2000

Saturation mapping of a gene-rich recombination hot spot region in wheat.

Physical mapping of wheat chromosomes has revealed small chromosome segments of high gene density and frequent recombination interspersed with relatively large regions of low gene density and infrequent recombination. We constructed a detailed genetic and physical map of one highly recombinant region on the long arm of chromosome 5B. This distally located region accounts for 4% of the physical size of the long arm and at least 30% of the recombination along the entire chromosome. Multiple crossovers occurred within this region, and the degree of recombination is at least 11-fold greater than the genomic average. Characteristics of the region such as gene order and frequency of recombination appear to be conserved throughout the evolution of the Triticeae. The region is more prone to chromosome breakage by gametocidal gene action than gene-poor regions, and evidence for genomic instability was implied by loss of gene collinearity for six loci among the homeologous regions. These data suggest that a unique level of chromatin organization exists within gene-rich recombination hot spots. The many agronomically important genes in this region should be accessible by positional cloning.

Biological Evolution↗
PubMed2003

Transpecific polymorphisms in an inversion linked esterase locus in Drosophila buzzatii.

Nucleotide variation was studied in a 1.1 kb section of the coding region of an Esterase gene (Est-A) that maps in the center of the segments rearranged by polymorphic inversions in the cactophilic Drosophila buzzatii. We examine 30 homozygous second-chromosome lines differing in gene arrangement and three D. koepferae isofemale lines as outgroups. Our data show that Est-A is a highly polymorphic gene at both synonymous and replacement sites. Significant departures from homogeneity in the distribution of the ratio of silent polymorphism to divergence predicted by the neutral theory reveals a local excess of silent polymorphism. This is consistent with the presence of two apparent narrow peaks of elevated silent polymorphism surrounding nonconservative amino acid substitutions. These polymorphisms as well as others at synonymous and nonsynonymous sites are shared with D. koepferae. We suggest that the presence of shared nucleotide polymorphisms is probably due to interspecific gene flow and/or balancing selection acting on replacement variants and/or to a decreased probability of loss of ancestral polymorphisms caused by linkage to an adaptive inversion polymorphism. Recurrent mutation and persistence of neutral ancestral polymorphisms cannot, however, be ruled out. The analysis of the distribution of nucleotide variation among the three chromosomal arrangements sampled reveals that derived arrangements (J and JZ(3)) are less polymorphic than the ancestral ST, and that the widely distributed ST and J arrangements are genetically differentiated. However, a significant number of polymorphisms are shared between arrangements, suggesting frequent exchange either from gene conversion or from double crossovers in heterokaryotypes. Finally, our present results in combination with data of sequence variation at the breakpoints of inversion J suggest that this old gene arrangement has risen in frequency in relatively recent times.

Animals↗
PubMed1996

Comparison of volume control and pressure control ventilation: is flow waveform the difference?

OBJECTIVE: To examine the hypothesis that a decelerating inspiratory flow waveform is responsible for improvements in gas exchange during pressure control ventilation for acute lung injury. DESIGN: Prospective, controlled, crossover study. MEASUREMENTS AND MAIN RESULTS: Twenty-five patients with acute lung injury requiring mechanical ventilation with a positive-end expiratory pressure > or = 10 cm H2O, ventilator frequency of > or = 8 bpm, inspired oxygen concentration of > or = 0.50, peak inspiratory pressure > or = 40 cm H2O, and requiring sedation and paralysis were studied. Patients were ventilated at a tidal volume of 10 mliters/kg, respiratory frequency was set to maintain a pH > 7.30 and PaCO2 < 50 mm Hg, and positive end-expiratory pressure (PEEP) set to maintain Pao2 > 70 mm Hg or Sao2 > 93% with an Fio2 < or = 0.50. In random sequence, ventilator mode was changed from volume control with a square flow waveform, pressure control ventilation with a decelerating flow waveform, or volume control ventilation with a decelerating flow waveform. Tidal volume, minute ventilation, and airway pressures were continuously measured at the proximal airway. After 2 hours of ventilation in each mode, arterial and mixed venous blood gases were drawn and cardiac output determined by thermodilution. Dead space to tidal volume ratio was determined from mixed expired gas concentrations and Paco2. During volume control ventilation with a square flow waveform, Pao2 was decreased (75 +/- 11 mm Hg vs. 85 +/- 9 mm Hg and 89 +/- 12 mm Hg), p < 0.05, and peak inspiratory pressure was increased (50 +/- 9 cm H2O vs. 42 +/- 7 cm H2O and 39 +/- 9 cm H2O) p < 0.05 compared to volume control with a decelerating flow waveform and pressure control ventilation. Mean airway pressure was also lower with volume control with a square flow waveform (17 +/- 4 cm H2O vs. 20 +/- 4 cm H2O and 21 +/- 3 cm H2O) compared to volume control with a decelerating flow waveform and pressure control ventilation. There were no differences in hemodynamic parameters. CONCLUSIONS: Both pressure control ventilation and volume control ventilation with a decelerating flow waveform provided better oxygenation at a lower peak inspiratory pressure and higher mean airway pressure compared to volume control ventilation with a square flow waveform. The results of our study suggest that the reported advantages of pressure control ventilation over volume control ventilation with a square flow waveform can be accomplished with volume control ventilation with a decelerating flow waveform.

Adult↗
PubMed2004

Melatonin pharmacotherapy for nocturia in men with benign prostatic enlargement.

PURPOSE: Nocturia is a common condition often attributed in aging men to benign prostatic enlargement. Older adults are prone to nocturnal sleep disturbance, of which disturbed circadian rhythm may be a component since it improves with nighttime administration of melatonin. This study was designed to investigate melatonin as a potential treatment for nocturia associated with bladder outflow obstruction in older men. MATERIALS AND METHODS: A total of 20 men with urodynamically confirmed bladder outflow obstruction and nocturia were entered into a randomized, double blind, placebo controlled crossover study assessing the effect of 2 mg controlled release melatonin at night on nocturia. Symptoms were assessed at baseline and after each 4-week treatment period using a frequency volume chart, the International Prostate Symptom Score and symptom problem index. Maximum urinary flow rate and post-void residual urine volume were also assessed. RESULTS: Baseline frequency of nocturia was 3.1 episodes per night. There were 7 men (35%) with detrusor overactivity and 10 (50%) had nocturnal polyuria. Melatonin and placebo caused a decrease in nocturia of 0.32 and 0.05 episodes per night (p = 0.07) and a decrease in the nocturia bother score of 0.51 and 0.05, respectively (p = 0.008). Nocturia responder rates (a reduction from baseline of at least -0.5 episodes per night) differed between the active medication and placebo groups (p = 0.04). Daytime urinary frequency, International Prostate Symptom Score, relative nocturnal urine volume, maximum urinary flow rate and post-void residual were unaffected by melatonin treatment. CONCLUSIONS: Melatonin treatment is associated with a significant nocturia response rate, improvement in nocturia related bother and a good adverse effect profile. However, it is uncertain whether the observed changes in this study are clinically significant.

Aged↗
PubMed2005

Effect of low-intensity acenocoumarol on frequency and severity of migraine attacks.

OBJECTIVE: To investigate the effect of low-intensity acenocoumarol treatment (target INR 1.5 to 2.0) on the frequency and severity of migraine attacks. BACKGROUND: The positive effect of anticoagulation on migraine has been described in case reports and observational studies. METHODS: We conducted a randomized, open, crossover study in migraine patients. After a run-in period of 8 weeks, all patients received acenocoumarol or propranolol during a period of 12 weeks and, after a washout period of 2 weeks, propranolol or acenocoumarol during a second period of 12 weeks. RESULTS: Nineteen patients fulfilling the criteria were included. In 12 patients with complete data collection, only one good responder could be noted. In the other patients, treatment with low-intensity acenocoumarol did not show improvement of migraine symptoms compared with the run-in period. Treatment with propranolol showed a trend towards improvement compared with the run-in period. No serious adverse events were observed. CONCLUSIONS: Overall, low-intensity acenocoumarol treatment has no prophylactic effect in migraine patients.

Acenocoumarol↗
PubMed1996

Effects of fenoterol on inspiratory effort sensation and fatigue during inspiratory threshold loading.

We studied the effects of a single dose of fenoterol on the relationship between inspiratory effort sensation (IES) and inspiratory muscle fatigue induced by inspiratory threshold loading in healthy subjects. The magnitude of the threshold was 60% of maximal static inspiratory mouth pressure (PI,mmax) at functional residual capacity, and the duty cycle was 0.5. Subjects continued the threshold loaded breathing until the target mouth pressure could no longer be maintained (endurance time). The intensity of the IES was scored with a modified Borg scale. Either fenoterol (5 mg) or a placebo was given orally 2 h before loading in a randomized double-blind crossover protocol. The endurance time with fenoterol (34.4 +/- 8.6 min) was longer than that with the placebo (22.2 +/- 7.1 min; P < 0.05). The ratio of high- to low-frequency power of the diaphragmatic electromyogram (EMGdi) decreased during loading; the decrease was less with fenoterol (P < 0.05). The EMGdi also decreased with loading; the decrease was greater on fenoterol treatment (P < 0.01). The PI,mmax and maximal transdiaphragmatic pressure (Pdi) were similarly decreased after loading on either treatment. The intensity of the IES rose with time during loading in both groups but was lower with fenoterol than with the placebo (P < 0.05). The ratio of Pdi to integrated activity of the EMGdi increased with fenoterol (P < 0.05). Fenoterol treatment increased both superimposed Pdi twitch and Pdi twitch of relaxed diaphragm and decreased the value of (1-superimposed Pdi twitch/Pdi twitch of relaxed diaphragm). Thus we conclude that in normal subjects fenoterol reduces diaphragmatic fatigue and decreases the motor command to the diaphragm, resulting in a decrease in IES during inspiratory threshold loading and a prolongation of endurance.

Adult↗
PubMed1989

Comparative efficacy of ketanserin and pentoxiphylline in treatment of Raynaud's phenomenon.

In a randomized, placebo-controlled, crossover study, 15 ambulatory patients with Raynaud's phenomenon, treated for three weeks with ketanserin 80 mg/day and pentoxiphylline 1,200 mg/day, were evaluated by subjective symptom scores, daily frequency and duration of attacks, and photoplethysmography, at room temperature and after cold test. Reduced subjective symptoms and duration of attacks, together with improved cold test plethysmography, were significant only after ketanserin. All subjective symptom scores also improved after ketanserin but only for cyanosis and paresthesia after pentoxiphylline. Excellent results were obtained in 4 cases after ketanserin and in 1 case with pentoxiphylline. The authors discuss the greater importance of antivasospastic action over antiaggregating and hemorheologic effects in Raynaud's phenomenon therapy, as well as the pathogenetic role of serotonin.

Adult↗
PubMed1989

Repeated application of EMLA cream 5% for the alleviation of cannulation pain in haemodialysis.

The analgesic effect and the occurrence of local reactions after repeated application of a lidocaine/prilocaine cream (EMLA 5%) were investigated in 31 haemodialysis patients. The cream was used for alleviation of cannulation pain prior to the haemodialysis (HD) for a period of 1-1.5 years. In each patient 300 to 312 applications of the cream were made during the period. Local skin reactions were recorded after the cream applications and the analgesic effect was evaluated with double-blind, crossover placebo controls at regular intervals. Seventeen patients completed the study. EMLA gave considerable pain relief and was significantly better than placebo at all effect evaluations but one. The frequency of local reactions was low and not correlated to the number of applications of EMLA. Two patients, however, interrupted their treatment due to local irritation.

Aged↗
PubMed2001

Evaluation of some properties of individual bioequivalence (IBE) from replicate-design studies.

BACKGROUND: One of the claimed benefits of the individual bioequivalence (IBE) approach has been that the aggregate regulatory model rewards a test formulation when it has a within-subject variation smaller than the reference product. Hauck et al. [1996] demonstrated that, in the absence of random variations, this property of IBE was due to the tradeoff between the difference of the means and the deviation between the intrasubject variances of the two formulations. The tradeoff was a consequence of the aggregate regulatory model. However, calculations of Endrenyi and Hao [1998] showed that, in the presence of random variations, not only rewards but also penalties can arise due to chance alone. METHODS: A data set of 55 investigations made public by the FDA in 1999 and containing replicate crossover designs was analyzed. Two parameters, AUC and Cmax, were determined in each investigation. RESULTS: The analyses of the FDA data indicate that: rewards and penalties occur at similar frequencies, large rewards and penalties are recorded quite often, and the aggregate IBE model is rather insensitive to the difference between the estimated means and is compatible with the frequent occurrence of large deviations. CONCLUSION: Rewards and penalties, apparently arising from random variations, can affect regulatory decisions on the acceptance of IBE and can lead to incorrect conclusions.

Area Under Curve↗
PubMed1991

[Usefulness of alprazolam in controlling cisplatin-induced emesis].

Usefulness of alprazolam for control of chemotherapy-induced emesis including 5-day continuous intravenous infusion of cisplatin for advanced lung cancer was evaluated by a randomized crossover design. Of 22 cases evaluated, 8 in the alprazolam group and 1 in the untreated group were free from nausea and vomiting (p less than 0.01). The mean frequency of vomiting in the alprazolam group was 1.18 times, which is significantly smaller than 2.25 times in the untreated group (p less than 0.05). The mean duration of vomiting and nausea was significantly shorter in the alprazolam group (p less than 0.01, p less than 0.05). It is thus concluded that concomitant therapy with the minor tranquilizer alprazolam is useful in treating cisplatin-induced acute or delayed emesis in which psychological and psychiatric factors are involved.

Adult↗
PubMed1981

The effects of weekly versus monthly ragweed allergen injections on immunological parameters.

The practice of administering injections of allergen extract at weekly intervals until maintenance levels are achieved is well established. However, no objective data exist to determine the optimal frequency of immunotherapy during the first few years after reaching maintenance therapy. Nine patients who had reached maintenance immunotherapy within the preceding year participated in a double-blind, crossover study to compare the effects of weekly versus monthly injections of ragweed antigen. The results were assessed by measurements of skin, nasal and conjunctival sensitivity to ragweed and serum levels of IgG and IgE antibodies specific for ragweed--all obtained at monthly intervals. There was a significant increase (P less than .05) in serum ragweed IgG levels when the subjects were receiving weekly injections as compared to monthly injections. There was also a definite trend toward decreased skin and conjunctival sensitivity to ragweed while receiving weekly injections. These data lend immunologic support to the practice of administering weekly injections during the pollen season in the first few years of allergy immunotherapy.

Adult↗