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PubMed2026

Effects of a programmed reflexology therapy on sleep quality, insomnia, and fatigue among individuals with poor sleep quality: evidence for autonomic nervous system modulation.

Poor sleep quality is closely associated with autonomic dysregulation and increased risks of cardiovascular, metabolic, and mental disorders. Foot reflexology is a widely used complementary therapy; however, its physiological mechanisms and comparative efficacy remain insufficiently explored. This study aimed to compare the effects of manual reflexology treatment (MRT) and foot massage equipment (FEM) on autonomic nervous system function, sleep quality, insomnia severity, and fatigue in adults with poor sleep quality. Using a randomized crossover design, 32 participants with poor sleep quality received MRT and FEM interventions for 6 weeks each (once weekly, 30-40 min/session). Heart rate (HR), blood pressure, and heart rate variability (HRV; time- and frequency-domain indices) were assessed at weeks 1 and 6 before and after each intervention. Subjective outcomes included the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and Fatigue Assessment Scale (FAS). Following MRT, participants demonstrated significantly greater reductions in global PSQI scores and all PSQI components compared with FEM. MRT also resulted in larger improvements in insomnia severity and both mental and physical fatigue. In contrast, FEM primarily improved physical fatigue. Physiologically, MRT induced an immediate decrease in HR and significant increases in HRV time-domain indices (SDNN, RMSSD, pNN50), which were sustained after 6 weeks. Frequency-domain analysis further revealed reduced LF, increased HF, and a lower LF/HF ratio, indicating enhanced parasympathetic activity and cumulative autonomic modulation. In conclusion, programmed manual reflexology, delivered according to the TIDieR framework, is more effective than mechanical foot massage in improving autonomic balance, sleep quality, insomnia severity, and fatigue in individuals with poor sleep quality. These findings support MRT as a feasible and evidence-based non-pharmacological complementary intervention for sleep health promotion. TRIAL REGISTRATION: clinicaltrials.gov; NCT Number: NCT07402460; Registered 3 February 2026.

Adult↗
PubMed2000

Use of percutaneous electrical nerve stimulation (PENS) in the short-term management of headache.

OBJECTIVE: To evaluate the short-term effects of percutaneous electrical nerve stimulation (PENS) in the management of three types of chronic headache. BACKGROUND: Traditional electroanalgesic therapies have been reported to be effective in the management of acute headache symptoms. However, no controlled studies have been performed in patients with chronic headache. METHODS: Thirty patients with either tension headache, migraine, or posttraumatic headache symptoms of at least 6 months' duration were randomized to receive PENS (needles with electricity) or "needles alone" according to a crossover study design. All treatments were administered for 30 minutes, three times a week for 2 consecutive weeks with 1 week off between the two different treatments. For the PENS treatments, an alternating electrical stimulation frequency of 15 and 30 Hz was used. Pain, activity, and sleep scores were assessed using a 10-cm visual analog scale, with 0 corresponding to the best and 10 to the worst, during the 48-hour period prior to the beginning of the two treatments, immediately before and after each treatment session, and 48 hours after completing each treatment modality. RESULTS: Compared with the needles alone, PENS therapy was significantly more effective in decreasing the overall VAS pain scores for tension-type headache, migraine and posttraumatic headache (58%, 59%, and 52% versus 20%, 15%, and 20%, respectively). Similarly, PENS therapy produced greater improvement in the patients' physical activity (41% to 58% for PENS versus 11% to 21% for needles only) and quality of sleep (41% to 48% for PENS versus 12% to 20% for needles only). However, there were no differences in the pattern of the response to PENS therapy among the three headache groups. CONCLUSIONS: Percutaneous electrical nerve stimulation appears to be a useful complementary therapy to analgesic and antimigraine drugs for the short-term management of headache. Interestingly, the analgesic response to PENS therapy appears to be independent of the origin of the headache symptoms.

Adult↗
PubMed1980

Inherited structural polymorphism of the fourth component of human complement.

Human fourth component of complement (C4) was found to be highly polymorphic by agarose gel electrophoresis of neuraminidase-treated plasma. The system allows clear-cut separation of the products of the two C4 genetic loci, C4A (acidic or Rodgers) and C4B (basic or Chido). There are at least six structural variants and a deletion allele at the C4A locus and two structural variants and a deletion allele at the C4B locus. Close linkage with no crossovers was found between the two C4 loci, allowing the definition of C4AB haplotypes, and between C4 haplotypes and the C2 and BF loci of the human histocompatibility complex. Nine C4 haplotypes, each with a frequency of 0.005 or more in Caucasians, were found. These studies provide direct evidence for two distinct but closely linked genetic loci for human C4 in the major histocompatibility complex on the short arm of chromosome 6.

Alleles↗
PubMed2003

Reciprocal crossovers and a positional preference for strand exchange in recombination events resulting in deletion or duplication of chromosome 17p11.2.

Smith-Magenis syndrome (SMS) is caused by an approximately 4-Mb heterozygous interstitial deletion on chromosome 17p11.2 in approximately 80%-90% of affected patients. Three large ( approximately 200 kb), complex, and highly homologous ( approximately 98%) low-copy repeats (LCRs) are located inside or flanking the SMS common deletion. These repeats, also known as "SMS-REPs," are termed "distal," "middle," and "proximal." The directly oriented distal and proximal copies act as substrates for nonallelic homologous recombination resulting in both the deletion associated with SMS and the reciprocal duplication: dup(17)(p11.2p11.2). Using restriction enzyme cis-morphism analyses and direct sequencing, we mapped the regions of strand exchange in 16 somatic-cell hybrids that harbor only the recombinant SMS-REP. Our studies showed that the sites of crossovers were distributed throughout the region of homology between the distal and proximal SMS-REPs. However, despite approximately 170 kb of high homology, 50% of the recombinant junctions occurred in a 12.0-kb region within the KER gene clusters. DNA sequencing of this hotspot (positional preference for strand exchange) in seven recombinant SMS-REPs narrowed the crossovers to an approximately 8-kb interval. Four of them occurred in a 1,655-bp region rich in polymorphic nucleotides that could potentially reflect frequent gene conversion. For further evaluation of the strand exchange frequency in patients with SMS, novel junction fragments from the recombinant SMS-REPs were identified. As predicted by the reciprocal-recombination model, junction fragments were also identified from this hotspot region in patients with dup(17)(p11.2p11.2), documenting reciprocity of the positional preference for strand exchange. Several potential cis-acting recombination-promoting sequences were identified within the hotspot. It is interesting that we found 2.1-kb AT-rich inverted repeats flanking the proximal and middle KER gene clusters but not the distal one. The role of any or all of these in stimulating double-strand breaks around this positional recombination hotspot remains to be explored.

Abnormalities, Multiple↗
PubMed1973

Gene conversion and transfer of genetic information within the inverted region of inversion heterozygotes.

Prior studies of recombination which monitor exchange events in exceedingly short intervals (i.e., separable sites within a cistron) reveal that the basic event in recombination involves a non-reciprocal transfer of information, termed conversion. As a logical consequence of the model suggested by the work in Drosophila, the present investigation examined recombination between rosy mutant alleles (ry:3-52.0) in Drosophila melanogaster in a paracentric inversion (In(3R)P(18)) heterozygote, which placed the rosy region approximately at the center of the inverted region. Comparison of the results of this study with experiments carried out in standard chromosome homozygotes reveals a dramatic suppression of classical crossovers between the rosy mutant alleles in the inversion heterozygote. However, conversions continue to occur for all rosy mutant alleles in all heterozygous combinations in the inversion heterozygote. Moreover, the order of magnitude of conversion frequencies seen in the inversion heterozygote does not change from that seen in the standard chromosome homozygote study. The significance of these observations with reference to the role of rearrangements as barriers of information transfer is discussed. Particular attention is directed to the elaborate inversion polymorphisms seen in natural populations, and to notions concerning their role in the evolution of adaptive gene complexes.

Animals↗
PubMed1995

Unequal homologous recombination of human DNA on a yeast artificial chromosome.

We examined unequal homologous DNA recombination between human repetitive DNA elements located on a yeast artificial chromosome (YAC) and transforming plasmid molecules. A plasmid vector containing an Alu element, as well as a sequence identical to a unique site on a YAC, was introduced into yeast and double recombinant clones analyzed. Recombination occurs between vector and YAC Alu elements sharing as little as 74% identity. The physical proximity of an Alu element to the unique DNA segment appears to play a significant role in determining the frequency with which that element serves as a recombination substrate. In addition, cross-over points of the recombination reaction are largely confined to the ends of the repetitive element. Since a similar distribution of crossover sites occurs during unequal homologous recombination in human germ and somatic tissue, we propose that similar enzymatic processes may be responsible for the events observed in our system and in human cells. This suggests that further examination of the enzymology of unequal homologous recombination of human DNA within yeast may yield a greater understanding of the molecular events which control this process in higher eukaryotes.

Base Sequence↗
PubMedDate not supplied

Bekesy-tracked aural harmonic distortion thresholds and uncomfortable loudness levels.

Sweep-frequency Bekesy audiometry was used to determine the uncomfortable loudness and threshold levels for the perception of an aurally generated harmonic distortion phenomenon in normal and sensorineural hearing impaired listeners. A continuous-interrupted tone crossover uncomfortable loudness level tracking pattern is described which appears to vary with the tracked aural harmonic distortion levels. Hearing impairment was seen to elevate the intensity required to achieve overload and distortion while reducing the range from audiometric threshold to the onset of aural harmonic distortion. Consideration of these findings to suprathreshold audiometric evaluation is discussed.

Adult↗
PubMed2005

Thermal conductivity and bulk viscosity in quartic oscillator chains.

We propose a relation which predicts the low-frequency thermal conductivity of a one-dimensional (1D) system from the thermal conductivity and bulk viscosity at higher frequency. Our theory is based on the assumption that "ballistic" transport by sound waves dominates the heat transport. For a system with equal heat capacities (c(p) = c(v)) this relation is particularly simple. We test the prediction by simulating a chain of particles with quartic interparticle potentials under zero pressure conditions. As the frequency omega --> 0 the theory predicts that the energy current power spectrum diverges as omega(-1/2), not seen in previous simulations. Because we simulate very long chains to long times we do observe the crossover into this regime. The bulk viscosity of a 1D chain has been determined via simulation. It is found to be finite for our system, in contrast to the thermal conductivity which is infinite.

Journal Article↗
PubMed1982

Tiaramide--a new oral drug for the treatment of asthma.

1 TIaramide, an anti-inflammatory drug, inhibits the action of mediators released from mast cells and has direct smooth muscle relaxant properties. It may therefore have a beneficial effect in asthma. 2 A double-blind crossover trial comparing the bronchodilator activity of tiaramide and placebo over 16 days was undertaken in 13 patients with asthma. 3 Peak expiratory flow rate (PEFR) was recorded on three separate occasions every day and frequency of salbutamol aerosol usage was noted on a diary card. 4 During treatment with tiaramide the mean mid-morning PEFR (362 1/min) was higher than mean PEFR on placebo (328) (P less than 0.001) as was the evening PEFR (378) compared with placebo (388) (P less than 0.001). 5 There was a significant reduction in daily use of the salbutamol inhaler whilst on tiaramide (1.8) compared with placebo (2.3) (P less than 0.05). 6. Tiaramide may be a useful addition to existing prophylactic treatment for asthma.

Adolescent↗
PubMed1983

Double-blind crossover trial of progabide versus placebo in severe epilepsies.

In this double-blind, two-period, crossover trial with randomized treatment assignment, progabide (+/- 30 mg/kg/day) and placebo were compared as add-on to standard therapy in 20 "therapy-resistant" epileptic patients (11 males, nine females; age range, 7-47 years). The duration of each treatment period was 6 weeks. Crossover was performed gradually over 3-4 days. Twenty-four patients entered the study: three dropped out for reasons unrelated to progabide effects; one dropped out during the placebo period because of increased seizure frequency. Of the 20 patients who completed the study, 14 had partial, two partial plus secondary generalized, and four generalized seizures. Preexisting antiepileptic treatment consisted of one antiepileptic drug (AED) in three, two AEDs in eight, three AEDs in five, and four AEDs in four patients (mean, 2.5 AEDs/patient). The following parameters were recorded at biweekly intervals: (a) efficacy parameters--total seizure count, counts of each seizure type, and global clinical judgment; (b) safety parameters--adverse drug effects, brief clinical and neurological examinations, and laboratory tests; and (c) plasma concentrations of progabide and of the associated AEDs. Twelve patients were considered to be improved (p less than 0.01) with progabide by global clinical judgment compared with two patients improved with placebo. Nine patients of 20 had a 48-100% reduction of total seizure count in the verum period, leading to a significant reduction of total seizure number and of complex partial seizures in the verum period as compared with the placebo period (p less than 0.05). Adverse effects were reported or observed in 10 patients during the progabide period and in five patients in the placebo period. The side effects were generally mild and consisted of somnolence in four cases and of tremors, dry mouth, troubles of equilibrium, anorexia, euphoria, depression, and anxiety in individual patients; a 15-20% reduction of the progabide dose was required in two cases only. No treatment-related alterations in results of laboratory tests were observed.

Adolescent↗
PubMed2005

Nonlinear analysis of heart rate variability during Qi therapy (external Qigong).

Heart rate variability (HRV) was compared in 30 subjects receiving external Qi therapy (EQT) or placebo control therapy, in a crossover design experiment. Subjects who received the EQT reported more pleasant and calm emotions than did the placebo group. Qi therapy reduced the heart rate and increased HRV as indicated by a reduced low frequency/high frequency power ratio of HRV. With nonlinear analysis, the Poincaré plot index of HRV and approximate entropy was greater in the EQT group than in the control group. These findings suggest that EQT stabilizes the sympathovagal function and cardiac autonomic nervous system by inducing more positive emotions than the placebo therapy. In conclusion, EQT may act by stabilizing both the autonomic nervous system and the emotional state.

Adult↗
PubMed2006

A link between meiotic prophase progression and crossover control.

During meiosis, most organisms ensure that homologous chromosomes undergo at least one exchange of DNA, or crossover, to link chromosomes together and accomplish proper segregation. How each chromosome receives a minimum of one crossover is unknown. During early meiosis in Caenorhabditis elegans and many other species, chromosomes adopt a polarized organization within the nucleus, which normally disappears upon completion of homolog synapsis. Mutations that impair synapsis even between a single pair of chromosomes in C. elegans delay this nuclear reorganization. We quantified this delay by developing a classification scheme for discrete stages of meiosis. Immunofluorescence localization of RAD-51 protein revealed that delayed meiotic cells also contained persistent recombination intermediates. Through genetic analysis, we found that this cytological delay in meiotic progression requires double-strand breaks and the function of the crossover-promoting heteroduplex HIM-14 (Msh4) and MSH-5. Failure of X chromosome synapsis also resulted in impaired crossover control on autosomes, which may result from greater numbers and persistence of recombination intermediates in the delayed nuclei. We conclude that maturation of recombination events on chromosomes promotes meiotic progression, and is coupled to the regulation of crossover number and placement. Our results have broad implications for the interpretation of meiotic mutants, as we have shown that asynapsis of a single chromosome pair can exert global effects on meiotic progression and recombination frequency.

Animals↗
PubMed1993

Induction of estrus after thyroidectomy in nonlactating Holstein cows.

Hypothyroidism reportedly decreased sexual behavior in several species. To confirm the role of hypothyroidism in the expression of estrus in cattle, our objective was to determine whether estrus could be induced in ovariectomized cows without intact thyroid glands using estradiol benzoate and progesterone. Eight nonlactating, nonpregnant Holstein cows were thyroidectomized and ovariectomized, and another four cows were ovariectomized only. All cows were given either estradiol benzoate in a crossover design with two replicates during 4 consecutive wk. Cows were observed continuously for estrus from 9 to 45 h after treatment with gonadal steroids. Intensity of estrus was assessed by quantitative measurement of the frequencies of mounting activity and standing behavior. The percentage of cows showing estrus was influenced by thyroidectomy-ovariectomy (78.1%) compared with ovariectomy (31.1%) but was unaffected by hormonal treatment. In contrast, other measures of estrous behavior (duration of standing estrus and frequencies of mounting and standing activities) were unaffected by thyroid status or by hormonal treatments. We concluded that ovariectomized cows without intact thyroid glands exhibit estrus and that the exhibited behavior is similar in intensity and duration to that in ovariectomized cows treated with gonadal steroids. Hypothyroidism may not cause failure to express estrus.

Animals↗
PubMed1979

A comparison of controlled-release aminophylline (Phyllocontin Continus tablets) and sympathomimetic bronchodilators.

In a crossover trial on twenty-four patients with reversible airways obstruction the rise in FEV1 on Phyllocontin Continus tablets (15%) was comparable to that achieved with Alupent tablets (14%). The usage of inhaled salbutamol and frequency of attacks of wheeziness were both greater when the patients were taking Alupent tablets. In a second study the effect of Phyllocontin tablets and Ventolin tablets both in combination with inhaled Ventolin and alone were examined. It was found that on Phyllocontin tablets alone patients showed a similar improvement (22%) in FEV1 to Ventolin tablets alone (19%). When inhaled Ventolin was added to Phyllocontin tablets a further rise in FEV1 was seen but not when inhaled Ventolin was added to Ventolin tablets.

Albuterol↗
PubMed1983

Bromocriptine improves reduced libido and potency in men receiving maintenance hemodialysis.

Twenty-five men on maintenance hemodialysis commenced a placebo-controlled, double-blind, crossover trial of bromocriptine for erectile impotence. Eight patients on bromocriptine and one on placebo failed to complete the trial due to side-effects and 2 were withdrawn following renal transplantation. Libido or the frequency and/or quality of erections or both improved in 11 of the remaining 14 patients during bromocriptine treatment. A significant (P less than 0.01) improvement in patients' perception of sexual performance occurred on bromocriptine compared with placebo. The 3 patients in whom potency failed to improve had the lowest serum testosterone concentrations. Bromocriptine is usually effective in the management of impotence in males receiving maintenance hemodialysis provided pretreatment serum testosterone is above the lower end of the normal range, but side-effects are relatively common.

Adult↗
PubMed1988

The effects of translocations on recombination frequency in Caenorhabditis elegans.

In the nematode Caenorhabditis elegans, recombination suppression in translocation heterozygotes is severe and extensive. We have examined the meiotic properties of two translocations involving chromosome I, szT1(I;X) and hT1(I;V). No recombination was observed in either of these translocation heterozygotes along the left (let-362-unc-13) 17 map units of chromosome I. Using half-translocations as free duplications, we mapped the breakpoints of szT1 and hT1. The boundaries of crossover suppression coincided with the physical breakpoints. We propose that DNA sequences at the right end of chromosome I facilitate pairing and recombination. We use the data from translocations of other chromosomes to map the location of pairing sites on four other chromosomes. hT1 and szT1 differed markedly in their effect on recombination adjacent to the crossover suppressed region. hT1 had no effect on recombination in the adjacent interval. In contrast, the 0.8 map unit interval immediately adjacent to the szT1(I;X) breakpoint on chromosome I increased to 2.5 map units in translocation heterozygotes. This increase occurs in a chromosomal interval which can be expanded by treatment with radiation. These results are consistent with the suggestion that the szT1(I) breakpoint is in a region of DNA in which meiotic recombination is suppressed relative to the genomic average. We propose that DNA sequences disrupted by the szT1 translocation are responsible for determining the frequency of meiotic recombination in the vicinity of the breakpoint.

Animals↗
PubMed1986

Prevention of postmetrizamide myelographic seizures in dogs, using 5% dextrose solution.

Diuresis by IV administration of 5% dextrose in a balanced electrolyte solution (BES) reduced the frequency of occurrence of postmyelographic seizures in dogs. In the first study, a single myelogram was obtained in 8 dogs without dextrose diuresis. Two of these dogs weighed greater than 15 kg and both had seizures after metrizamide myelography. The remaining 6 dogs weighed less than 15 kg and only 2 had seizures. Greater body weight may have increased the risk of postmyelographic convulsions. In a crossover study, myelograms were obtained in 12 dogs weighing 20 to 31 kg. Six dogs were given 5% dextrose in BES (20 ml/kg of body weight/hr [diuresed]) and 6 were given BES alone (10 ml/kg/hr [not diuresed]). When myelography was repeated 10 days later, the 6 dogs that had been given 5% dextrose in BES were given BES only and the 6 dogs that had been given BES alone were given 5% dextrose in BES. The frequency of convulsions after metrizamide myelography was lower when dogs were given dextrose (33%) than when they were not (100%).

Animals↗
PubMed2000

Anomalies on capture nets of Hydropsyche slossonae larvae (Trichoptera; Hydropsychidae) following a sublethal chronic exposure to cadmium.

A laboratory study on the sublethal effects of cadmium (Cd) on the net-spinning process of the larvae of Hydropsyche slossonae was conducted in order to assess the potential of net anomalies as an indicator of chronic exposure to Cd. Two major anomalies with different frequency levels were identified after chronic exposure to 0.37, 1.2, 11.6, 21.4 and 43.3 microg l(-1) of Cd. The first was a distortion of the midline meshes where the diamond-shape structure is disrupted and the meshes are separated by extra strands (called 'midline' anomaly). The second aberration consisted of a distortion of the rectilinear structure of net opening by strands being fused or added over the meshes (called 'crossover' anomaly). The midline distortion may be linked to a physiological stress caused by Cd, which can affect the control of the net-spinning process. It was not possible to relate the crossover aberrations to a specific toxic action of Cd, but data indicated that both anomalies are independent from each other and that two modes of action could be implicated. Protein analyses of capture nets have revealed silk polypeptide modifications at the highest Cd concentration tested, indicating a possible effect of Cd interaction with silk proteins. However, neither a gradient-concentration nor a time-dependent response could be established with both aberration frequencies. Silk protein modifications would rather play a secondary role in the appearance of both net anomalies, and mostly at a high concentration level. Finally, the toxicity curves (EC(50)) show that the sensitivity threshold for both types of aberration ranged from 1 to 5 microg l(-1) which is highly sensitive compared with other sublethal effects of Cd on other macroinvertebrate species. Hence, the use of capture-net anomalies of hydropsychid larvae would represent a valuable indicator of sublethal toxicity induced by Cd and possibly by other metals in running waters.

Journal Article↗