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PubMed2006

Linear and nonlinear hearing aid fittings--2. Patterns of candidature.

We studied candidature for linear, slow-acting AVC hearing aids, and fast-acting WDRC hearing aids in a within-subject within-device crossover design of 50 listeners with SNHL. Candidature dimensions include HTLs, ULLs, spectro-temporal and masking abnormalities, cognitive capacity, and self-reports and acoustic measures of auditory ecology. Better performance with linear fittings is associated with flatter audiograms, wider dynamic range, and smaller differences in dynamic range between low and high frequencies, and also with more restricted auditory lifestyles. Better performance with all nonlinear fittings is associated with more sloping audiograms, more restricted dynamic ranges, greater differences in dynamic range between low and high frequencies, and more varied auditory lifestyles. Differential performance between WDRC and AVC fittings is associated with patterns of variation in auditory ecology (rapid versus slow changes) and cognitive (high versus low) capacity. Differential performance between WDRC in two channels, and a hybrid with WDRC in a low-frequency and AVC in a high-frequency channel is associated with psychoacoustic tests of cochlear function (high susceptibility to spectral and temporal smearing, and high susceptibility to upward spread of masking respectively). Patterns of candidature include measures beyond auditory function in the domains of cognitive capacity and auditory ecology.

Aged↗
PubMed2000

Topography of clonidine-induced electroencephalographic changes evaluated by principal component analysis.

BACKGROUND: Principal component analysis is a multivariate statistical technique to facilitate the evaluation of complex data dimensions. In this study, principle component analysis was used to reduce the large number of variables from multichannel electroencephalographic recordings to a few components describing changes of spatial brain electric activity after intravenous clonidine. METHODS: Seven healthy volunteers (age, 26 +/- 3 [SD] yr) were included in a double-blind crossover study with intravenous clonidine (1.5 and 3.0 microg/kg). A spontaneous electroencephalogram was recorded by 26 leads and quantified by standard fast Fourier transformation in the delta, theta, alpha, and beta bands. Principle component analysis derived from a correlation matrix calculated between all electroencephalographic leads (26 x 26 leads) separately within each classic frequency band. The basic application level of principle component analysis resulted in components representing clusters of electrodes positions that were differently affected by clonidine. Subjective criteria of drowsiness and anxiety were rated by visual analog scales. RESULTS: Topography of clonidine-induced electroencephalographic changes could be attributed to two independent spatial components in each classic frequency band, explaining at least 85% of total variance. The most prominent effects of clonidine were increases in the delta band over centroparietooiccipital areas and decreases in the alpha band over parietooccipital regions. Clonidine administration resulted in subjective drowsiness. CONCLUSIONS: Data from the current study supported the fact that spatial principle component analysis is a useful multivariate statistical procedure to evaluate significant signal changes from multichannel electroencephalographic recordings and to describe the topography of the effects. The clonidine-related changes seen here were most probably results of its sedative effects.

Adult↗
PubMed1991

Acute tolerance from benzodiazepine night sedation.

The hypothesis that benzodiazepine night sedation causes acute tolerance to benzodiazepine sedation given the following morning was examined in six volunteers in a double blind, randomised, crossover study. Before each of three study days, subjects received midazolam 15 mg or flunitrazepam 2 mg or placebo as oral night sedation. They were then given intravenous midazolam 5 mg the following morning and the resulting sedative effects examined, using an observers sedation scale and a psychomotor test battery (critical flicker fusion frequency, digit-symbol substitution, reflex time, tapping test and a visual analogue sedation scale). Although a consistent pattern emerged with the greatest degree of sedation following the placebo night sedation and the least degree of sedation following the midazolam, with flunitrazepam intermediate, no statistically significant differences were present between the three treatment groups. The results indicate that single use of benzodiazepine night sedation is not an important influence on benzodiazepine requirements for intravenous sedation.

Adult↗
PubMed1975

Isolation and characterization of mutator strains of Escherichia coli K-12.

A selection procedure was devised to select for mutants of Escherichia coli K-12 with enhanced rates of spontaneous frameshift mutation. Three types of mutants were isolated. Two of the mutations apparently represent alleles of previously isolated mutL13 and mutS3. The third type of mutation, represented by two alleles, lies between lysA and thyA, and has been designated mutR. mutR increases the rate of spontaneous frameshift mutation and also the rate of base substitution mutations. The mutator phenotype is recessive. Reversion of a lac amber mutation located on an episome is increased in the presence of the mutator, indicating that mutR can act in trans. No change in sensitivity to ultraviolet irradiation or mitomycin C could be found when mutR34 was compared to the isogenic mutR+ strain. The mutator's activity was little affected by the type of medium in which the strain was grown. Deoxyribonucleoside triphosphate pools were normal in mutR34. Intergenic recombination frequencies were the same in mutR and mutR and mutR+ strains, but a two- to threefold increase in intragenic recombination was observed in Hfr times Fminus crosses when the recipeint was mutR34 as compared with mutR+. This increase appeared independent of the distance between the two markers within the gene in which the crossover took place.

Alleles↗
PubMed1991

Replacement recombination in Lactococcus lactis.

In the pUC18-derived integration plasmid pML336 there is a 5.3-kb chromosomal DNA fragment that carries the X-prolyl dipeptidyl aminopeptidase gene (pepXP). The gene was inactivated by the insertion of an erythromycin resistance determinant into its coding sequence. Covalently closed circular DNA of pML336 was used for the electrotransformation of Lactococcus lactis. In 2% of the erythromycin-resistant transformants the pepXP gene was inactivated by a double-crossover event (replacement recombination) between pML336 and the L. lactis chromosome. The other transformants in which the pepXP gene had not been inactivated carried a Campbell-type integrated copy of the plasmid. Loss of part of the Campbell-type integrated plasmid via recombination between 1.6-kb nontandem repeats occurred with low frequencies that varied between less than 2.8 x 10(-6) and 8.5 x 10(-6), producing cells with a chromosomal structure like that of cells in which replacement recombination had taken place.

Chromosomes, Bacterial↗
PubMed2003

Humidified nasal continuous positive airway pressure in obstructive sleep apnoea.

Heated humidification of nasal continuous positive airway pressure (nCPAP) reduces upper airway symptoms and improves initial use in obstructive sleep apnoea syndrome (OSAS). The present study aimed to assess the effect of heated humidification of nCPAP on upper airway symptoms and initial use in obstructive sleep apnoea. This study was of a randomised, crossover design. Subjects with polysomnographically confirmed OSAS were randomised to 3 weeks nCPAP treatment with heated humidification (nCPAP-humid) or placebo humidification (nCPAP pl-humid). Objective and subjective nCPAP use, upper airway symptoms, and treatment satisfaction were compared. Thirty seven of 42 patients completed the protocol. nCPAP-humid reduced the frequency of adverse upper airway symptoms. nCPAP use over 3 weeks was greater with nCPAP-humid compared with nCPAP pl-humid. No difference was found between the treatment arms in terms of subjective treatment satisfaction or alertness. Heated humidification of nasal continuous positive airway pressure reduces upper airway symptoms and is associated with a small increase in initial use but not subjective sleepiness or treatment satisfaction. The results support the use of heated humidification as a strategy to reduce side-effects related to continuous positive airway pressure but not routine initial use.

Adult↗
PubMed2004

Comparative effect of repeated ingestion of difructose anhydride III and palatinose on the induction of gastrointestinal symptoms in humans.

We evaluated the safety and change in fermentability from repeated ingestion of difructose anhydride III (DFAIII) in humans. A randomized controlled single-blind crossover study with thirteen subjects was conducted. Each subject ingested 5 g of DFAIII or palatinose daily for 12 days, before and after which the subject was loaded with 10 g of DFAIII and had breath hydrogen measured from 0 to 9 h (DL test) to evaluate the fermentability of DFAIII. The defecation frequency and abdominal symptom score were the same between each ingestion period. Moreover, DFAIII ingestion had no influence on blood test results. Only the breath hydrogen excretion in post-DFAIII ingestion was slightly higher at h 8 than the pre-ingestion. Consequently, repeated ingestion of DFAIII for 12 days was as safe as palatinose ingestion, especially with respect to abdominal symptoms and blood test results, and its high resistance to enterobacterial fermentation in humans was not impaired.

Abdominal Pain↗
PubMed1997

Effect of nursing in the head elevated tilt position (15 degrees) on the incidence of bradycardic and hypoxemic episodes in preterm infants.

OBJECTIVE: We investigated whether nursing in the head elevated tilt position (HETP), compared with the horizontal position, has any effect on the incidence of bradycardic and hypoxemic episodes in preterm infants. METHODS: Twelve spontaneously breathing preterm infants with idiopathic recurrent apnea were studied in a randomized controlled crossover trial. Nine infants were treated with aminophylline. Each spent a total of 24 hours in the horizontal prone position and a total of 24 hours in HETP (prone, 15 degrees). The position was changed in random order every 6 hours. Thoracic impedance, heart rate, and arterial oxygen saturation were recorded continuously. The frequency of isolated hypoxemia (arterial saturation <80%), of isolated bradycardia (heart rate <90 beats per minute), and of mixed events was analyzed and compared without knowledge of the allocated position. RESULTS: In total, there were significantly fewer bradycardic and/or hypoxemic episodes (28.2%) in HETP compared with the horizontal position (mean difference, 13.35 episodes/24 hours; 95% confidence interval [CI]: 5.9- 20.8). The decrease was largest for isolated hypoxemic episodes (48.5%; mean difference, 11.74 episodes/24 hours; 95% CI: 6.1-17.4). Isolated bradycardic episodes (mean difference, 2.27 episodes/24 hours; 95% CI: -0.78-5.31) and mixed events were not decreased significantly in HETP. CONCLUSIONS: Nursing in a moderately tilted position (15 degrees) reduces hypoxemic events in preterm infants. This intervention is easy to apply, quickly reversible, and can be combined with drugs such as aminophylline.

Apnea↗
PubMed1991

Pharmacokinetics and EEG effects of flumazenil in volunteers.

The effect of intravenous flumazenil 10 mg on the electroencephalogram (EEG) was investigated in 7 volunteers in a placebo-controlled, randomised, double-blind, crossover study. The EEG was recorded between Fp1-M1 and Fp2-M2 and analysed using an aperiodic analysis technique. Two volunteers were excluded from the study because of significant asymmetry between baseline EEG recordings of the left and right hemisphere, in the remainder there were no changes in the beta-frequency range (12 to 30 Hz) or in other ranges of the EEG during or after flumazenil or placebo administration, with regard to the parameters total number of waves per second or total amplitude per second. There were no changes in heart rate, respiratory rate or blood pressure after administration of flumazenil or placebo. Three volunteers reported feelings of 'pressure to move' during the initial 2 min of the flumazenil infusion. The pharmacokinetics of flumazenil were investigated in the same volunteers. Flumazenil 10 mg was administered intravenously over 10 min; the data from 1 volunteer were excluded from this analysis because of blood sampling problems. The plasma concentration-time data of the remaining 6 volunteers were characterised by a biexponential function. The pharmacokinetic parameters were (mean +/- SD): initial volume of distribution, 16 +/- 5.7L; volume of distribution at steady-state, 64.8 +/- 12.5L; total body clearance, 53.8 +/- 1.2 L/h; distribution half-life, 4.1 +/- 1.3 min; and elimination half-life, 70.2 +/- 9.9 min. The authors conclude that flumazenil has no significant EEG effects. The rapid distribution and elimination of flumazenil may explain its previously reported short duration of action after intravenous anaesthesia with high doses of midazolam.

Adolescent↗
PubMed1998

[Vesicoureteral reflux and urinary incontinence in myelodysplastic patients: a comparison between those who had anti-reflux surgery alone and those who were treated by anti-reflux surgery combined with bladder augmentation with or without sling operation].

BACKGROUND: Vesicoureteral reflux and urinary incontinence are frequently observed among myelodysplastic patients. Since the conservative therapy is not always effective to improve these pathologies, surgical intervention is necessary for some of the patients. METHODS: Thirty-eight myelodysplastic patients were divided into 2 groups: Group A comprised 17 patients who had been operated by anti-reflux surgery (crossover method) alone and Group B 21 patients who had undergone anti-reflux surgery (Orikasa's method) and augmentation enterocystoplasty with or without sling operation. Cessation rate of reflux, bladder capacity, bladder compliance and operative complications were analyzed in the 2 groups. A questionnaire was sent to the patient asking to answer frequency of clean intermittent catheterization (CIC), severity of urinary incontinence, satisfaction rate for operation and so on. Mean followed-up periods were 11.7 (5.3-13.6) years for Group A and 3.7 (0.6-6.9) years for Group B, respectively. RESULTS: Reflux was successfully eradicated in 19 of 24 ureters (79%) of Group A and in 25 of 29 ureters (86%) of Group B, which was not significantly different. In Group A, bladder capacity and compliance slightly improved. The latter, however, remained less than 10 ml/cmH2 O. Bladder capacity and compliance of Group B increased more than twice the original value with statistical significance. Operative complication in Group A was ureteral obstruction in 1 patient, which eventually necessitated peritoneal dialysis. In Group B revision of ventriculoperitoneal shunt was necessary in 4 patients, incomplete ileus was conservatively treated in 3, and a bladder stone was formed in 1. The patients assessed that frequency of pyelonephritis was less in Group B compared to Group A. Other subjective parameters, however, such as frequency of CIC, severity of urinary incontinence, postoperative changes in the amount of urinary incontinence, and satisfaction rate for operation, were not different between the 2 groups. COMMENTS: Though operation-related complications occurred more frequently in those of Group B, these patients enjoyed significant improvement in bladder capacity and bladder compliance. We conclude when the conservative therapy fails to cure and improve vesicoureteral reflux and urinary incontinence, surgical interventions including anti-reflux surgery and augmentation cystoplasty with or without sling operation are recommended as a treatment option.

Adolescent↗
PubMed2004

[Diagnostics of larval toxocariasis].

PURPOSE OF THE STUDY: The paper, conceived as a retrospective study, resumes the results of our own investigations of the presence of serum IgG antibodies against Toxocara canis (as a crossover also against T. cati) in the sera of patients suspected of presenting larval toxocariasis in the region of Eastern Bohemia of the Czech Republic in the years 1997-2002. Our aim was to determine the immunity rate of IgG, its relationship to age and sex, further the whole range of diagnoses, the frequency of demands for such an examination by physicians and the evaluation of our experience with the detection of low avidity IgG. MATERIAL AND METHODS: With a commercial diagnostic kit the ELISA method was used to detect the presence of IgG antibodies against T. canis in 2 994 sera. IgG avidity was determined in 92 positive samples with an avidity solution, which is included in the diagnostic kit and has been used in our laboratory since 2001. RESULTS: The immunity rate of larval toxocariasis in our set was 20.4 % (612 samples). With age this rate increases (in individual decades of life - 11.9; 8.3; 11.4; 17.9; 26.1; 29.8 and 34.2%). Up to adolescence positive findings predominate among boys (males 0-10 years 84.2 %; 11-20 years 76 %). In the third decade we see a dramatic change in favour of women (women 21-30 years - 74.6 %). In absolute figures the number of positive findings stagnates in men after the age of 30 years, while among women positive findings continue to grow - yet expressed in percentages there is signifinct change in the male-female ratio (beginning with the 4th decade we find among the women 61.2; 69.7; 72.6 and 64.8 %). Physicians' interest in the diagnosis of toxocariasis in the years 1997-2002 is confirmed by the significantly higher number of investigated samples (135; 446; 617; 422; 558; 816). This, however, does not go hand in hand with a higher proportion of IgG positivity. IgG avidity was investigated in 92 positive samples - low avidity was confirmed in six of them (6.5 %); the appropriate case histories are not a part of the study. CONCLUSIONS: Our results tally with the data published by other departments in the Czech Republic. They confirm that the methods used have, as before, their place in the diagnostic range of microbiological laboratories.

Adolescent↗
PubMed1991

Dose proportionality of pharmacokinetics with a cr-verapamil formulation.

The relatively short half life of verapamil necessitates divided daily dosing in the treatment of angina, hypertension and arrhythmia. To reduce dosing frequency and increase patient compliance and therapeutic efficacy, a controlled-release once-daily verapamil formulation (Verelan) has been developed in three dosage strengths, 120 mg, 240 mg and 360 mg. In order to investigate the dose linearity of this formulation in the 120 mg and 360 mg dose range, un unblinded, crossover, comparative evaluation of the three dosage strengths was performed in a population of 27 male volunteers. Each treatment period lasted nine days with a minimum of 7 days between periods. On Days 1 and 2 of each treatment period, the single dose phase was evaluated following administration of medication on Day 1 only with regular blood sampling over the 48 hour period. On Days 3 and 7 inclusive, the five-day steady phase was evaluated. Mean plasma profiles following administration of each dose demonstrated extended verapamil absorption up to 24 hours after dosing. In both the single dose and steady state phases a linear relationship was observed between increasing dose and pharmacokinetic response over the dose range of 120 mg and 360 mg. This linearity in response with increasing dose is in contrast to the non-linearity of verapamil's pharmacokinetics with conventional verapamil formulations previously described by an number of workers and may be due to a saturation of verapamil's hepatic first pass metabolic pathway.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1996

The UCUAAAC promoter motif is not required for high-frequency leader recombination in bovine coronavirus defective interfering RNA.

The 65-nucleotide leader on the cloned bovine coronavirus defective interfering (DI) RNA, when marked by mutations, has been shown to rapidly convert to the wild-type leader of the helper virus following DI RNA transfection into helper virus-infected cells. A model of leader-primed transcription in which free leader supplied in trans by the helper virus interacts by way of its flanking 5'UCUAAAC3' sequence element with the 3'-proximal 3'AGAUUUG5' promoter on the DI RNA minus strand to prime RNA replication has been used to explain this phenomenon. To test this model, the UCUAAAC element which occurs only once in the BCV 5' untranslated region was either deleted or completely substituted in input DI RNA template, and evidence of leader conversion was sought. In both cases, leader conversion occurred rapidly, indicating that this element is not required on input RNA for the conversion event. Substitution mutations mapped the crossover region to a 24-nucleotide segment that begins within the UCUAAAC sequence and extends downstream. Although structure probing of the bovine coronavirus 5' untranslated region indicated that the UCUAAAC element is in the loop of a prominent stem and thus theoretically available for base pair-directed priming, no evidence of an unattached leader early in infection that might have served as a primer for transcription was found by RNase protection studies. These results together suggest that leader conversion on the DI RNA 5' terminus is not guided by the UCUAAAC element and might arise instead from a high-frequency, region-specific, homologous recombination event perhaps during minus-strand synthesis rather than by leader priming during plus-strand synthesis.

Animals↗
PubMed1994

Effect of beta-blockade on heart rate variability in patients with coronary artery disease.

OBJECTIVES: This study assessed the effects of beta-blockade on heart rate variability in patients with coronary artery disease and determined whether the effects of metoprolol in a controlled-release formulation and atenolol differ with regard to electrocardiographic measures of cardiac autonomic control. BACKGROUND: Low heart rate variability is common in coronary artery disease and is associated with increased mortality. Beta-adrenergic blocking drugs may increase heart rate variability in healthy subjects, but there is limited knowledge of whether they are able to modify heart rate variability in patients with uncomplicated coronary artery disease. METHODS: In a randomly allocated, double-blind crossover study with three 2-week treatment periods, 200 mg of controlled-release metoprolol once a day, 100 mg of atenolol once a day or placebo once a day were administered in 18 male patients with stable coronary artery disease. The 24-h heart rate variability was measured in both the time and frequency domains. RESULTS: Beta-blockade induced a significant increase in heart rate variability, but no significant differences were found between atenolol and metoprolol. The average 24-h high frequency power increased by 64% after atenolol and by 62% after metoprolol. The root-mean-square successive difference of normal RR intervals increased by 70% after atenolol and by 62% after metoprolol, and the standard deviations of RR intervals increased by 20% and 16%, respectively. Beta-blockade had no significant effects on the amplitude of the circadian rhythm of heart rate variability, although both metoprolol and atenolol blunted the abrupt decrease of high frequency power after arousal. CONCLUSIONS: Beta-blockade by metoprolol and atenolol enhance the heart rate variability in patients with coronary artery disease. This may contribute to the protective effects of beta-blockade in ischemic heart disease.

Adolescent↗
PubMedDate not supplied

A comparison of insulin lispro and buffered regular human insulin administered via continuous subcutaneous insulin infusion pump.

This study compared glycemic control achieved with insulin lispro or buffered regular human insulin in patients with Type 1 diabetes treated with continuous subcutaneous insulin infusion (CSII) using an external insulin pump. In this 24-week multicenter, randomized, two-way crossover, open-label trial, 58 patients on CSII with adequate glycemic control received either insulin lispro or buffered regular human insulin for 12 weeks, followed by the alternate treatment for another 12 weeks. Efficacy and safety measures included hemoglobin A(1c) (HbA(1c)) at baseline and endpoint, home blood glucose monitoring, hypoglycemia, and frequency of pump catheter occlusion. Patients consumed a standard test meal on three occasions, with determinations of fasting, 1- and 2-h postprandial glucose values. Insulin lispro use was associated with a significantly lower HbA(1c) than was buffered regular human insulin (7.41+/-0.97 vs. 7.65+/-0.85 mmol/l; P=.004). Fasting serum glucose values before the test meal were similar between the two therapies. The 1-h (11.16+/-4.29 vs. 13.20+/-4.68 mmol/l; P=.012) and 2-h (9.64+/-4.10 vs. 12.53+/-4.64 mmol/l; P=.001) postprandial glucose concentrations were significantly lower during treatment with insulin lispro. No differences between treatments were observed in basal or bolus insulin doses, weight gain, or the incidence and rate of hypoglycemia, hyperglycemia, or pump occlusions. When used in external pumps, insulin lispro provides better glycemic control than buffered regular human insulin with a similar adverse event profile.

Adult↗
PubMed1999

The properties of chimeric picornavirus IRESes show that discrimination between internal translation initiation sites is influenced by the identity of the IRES and not just the context of the AUG codon.

The internal ribosome entry segment (IRES) of picornaviruses consists of approximately 450 nt of 5'-untranslated region, terminating at the 3' end with an approximately 25 nt element consisting of an absolutely conserved UUUC motif followed by a more variable pyrimidine-rich tract and G-poor spacer, and finally an AUG triplet, which is considered to be the actual ribosome entry site. Events following entry at this site differ among picornaviruses: in encephalomyocarditis virus (EMCV) virtually all ribosomes initiate translation at this site (AUG-11); in foot-and-mouth-disease virus (FMDV), one-third of the ribosomes initiate at this AUG (the Lab site), and the rest at the next AUG 84 nt downstream (Lb site); and in poliovirus (PV), the AUG at the 3' end of the IRES (at nt 586 in PV type 1) is considered to be a silent entry site, with all ribosomes initiating translation at the next AUG downstream (nt 743). To investigate what determines this different behavior, chimeras were constructed with a crossover at the conserved UUUC motif: the body of the IRES, the sequences upstream of this UUUC motif, was derived from one species, and the downstream sequences from another. When the body of the FMDV or PV IRESes was replaced by that of EMCV, there was a marked increase in the absolute and relative frequency of initiation at the upstream AUG, the Lab site of FMDV and 586AUG of PV, respectively. In contrast, when the body of the EMCV IRES was replaced by that of PV, initiation occurred with no preference at three AUGs: the normal site (AUG-11), AUG-10 situated 8 nt upstream, and AUG-12, which is 12 nt downstream. Thus although the context of the AUG at the 3' end of the IRES may influence initiation frequency at this site, as was shown by improving the context of 586AUG of PV, the behavior of the ribosome is also highly dependent on the nature of the upstream IRES. Delivery of the ribosome to this AUG in an initiation-competent manner is particularly efficient and accurate with the EMCV IRES.

5' Untranslated Regions↗
PubMed1992

Effects of mutagen-sensitive mus mutations on spontaneous mitotic recombination in Aspergillus.

Methyl methane-sulfonate (MMS)-sensitive, radiation-induced mutants of Aspergillus were shown to define nine new DNA repair genes, musK to musS. To test mus mutations for effects on mitotic recombination, intergenic crossing over was assayed between color markers and their centromeres, and intragenic recombination between two distinguishable adE alleles. Of eight mutants analyzed, four showed significant deviations from mus+ controls in both tests. Two mutations, musK and musL, reduced recombination, while musN and musQ caused increases. In contrast, musO diploids produced significantly higher levels only for intragenic recombination. Effects were relatively small, but averages between hypo- and hyperrec mus differed 15-20-fold. In musL diploids, most of the rare color segregants resulted from mitotic malsegregation rather than intergenic crossing over. This indicates that the musL gene product is required for recombination and that DNA lesions lead to chromosome loss when it is deficient. In addition, analysis of the genotypes of intragenic (ad+) recombinants showed that the musL mutation specifically reduced single allele conversion but increased complex conversion types (especially recombinants homozygous for ad+). Similar analysis revealed differences between the effects of two hyperrec mutations; musN apparently caused high levels solely of mitotic crossing over, while musQ increased various conversion types but not reciprocal crossovers. These results suggest that mitotic gene conversion and crossing over, while generally associated, are affected differentially in some of the mus strains of Aspergillus nidulans.

Aspergillus nidulans↗
PubMed2001

Effect of topical heat on electromyographic power density spectrum in subjects with myofascial pain and normal controls: a pilot study.

OBJECTIVE: To investigate the influence of superficial heat on the fatigue cascade of the upper trapezius muscle in subjects with myofascial pain and matched normal controls. DESIGN: In a prospective randomized block crossover pilot study, eight female subjects, ages 20-35 yr, with upper trapezius muscle trigger points and eight matched female control subjects without pain were studied. Subjects performed six 100-sec shoulder shrug contractions to fatigue, with subjects randomly chosen to receive heat during the first three or last three trials. The initial median frequency and the slope of the median frequency decline were calculated from the data. RESULTS: In the subjects with pain, the slope of the median frequency was elevated in ambient room temperature as compared with controls. There was no difference in slope of the median frequency under heated conditions. Heat application in controls before fatiguing exercise caused an increase in initial median frequency, whereas exercise before heat treatment resulted in a significantly lower initial median frequency. Subjects with myofascial pain had no significant change in initial median frequency. CONCLUSIONS: Heat seems to have a positive effect on muscle function in normal individuals when applied before exercise. Subjects with myofascial pain respond differently to exercise and heat challenge, which suggests a difference in their muscle physiology.

Adult↗