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PubMed1982

Lactose malabsorption and tolerance of lactose-hydrolyzed milk. A double-blind controlled crossover study.

Eleven lactose-intolerant patients were investigated in a double-blind crossover controlled study. In random sequence they received 500 ml of either ordinary cow milk (lactose content, 25 g) or the same amount of low-lactose milk (85% of the lactose hydrolyzed), which had been processed by Lactozym 3000 L for 24 h at 4 degrees C. A significantly increased blood glucose rise from fasting levels was demonstrated in the low-lactose tests. Similarly, a significant reduction of liquid stool frequency, abdominal colics, distention, borborrhygmia, and flatulence was demonstrated. It was concluded that further studies, including long-term treatment of lactose-intolerant children, are indicated.

Adult↗
PubMed1989

Comparison of high-frequency oscillatory ventilation and high-frequency jet ventilation in cats with normal lungs.

Four adult cats received alternating high-frequency oscillatory ventilation (HFOV) and high-frequency jet ventilation (HFJV) at equivalent proximal airway pressures. Physiologic measurements were made before and after each ventilator change. Proximal airway pressures were then adjusted as necessary to reestablish normal pH and PaCO2 values. Aortic, pulmonary artery, and central venous pressures were monitored. Cardiac outputs were measured. Pulmonary and systemic vascular resistance, intrapulmonary shunt, and alveolar-arterial oxygen gradient were determined. Following the change from HFOV to HFJV at similar proximal airway pressures, HFJV always produced higher pH values (P less than 0.0001), higher PaO2 values (P less than 0.05), lower PaCO2 values (P less than 0.0001), as well as higher cardiac outputs (P less than 0.01), lower pulmonary artery pressures (P less than 0.001), and lower pulmonary vascular resistances (P less than 0.001). Following the reciprocal crossover, from HFJV to HFOV, HFJV pH values were again higher (P less than 0.001), and PaCO2 values were again lower (P less than 0.001). A comparison of HFOV and HFJV at similar pH and PaCO2 values showed that HFOV consistently required higher peak inspiratory pressures (P less than 0.001), higher mean airway pressure (P less than 0.001), and higher pressure wave amplitudes (P less than 0.001). Under the circumstances of this study, HFJV produced better gas exchange at lower proximal airway pressures.

Airway Resistance↗
PubMed1995

Nifedipine in migraine and tension headache: a randomised double blind crossover study.

Nifedipine was evaluated in the prophylaxis of 28 patients each of migraine and tension headache using a double blind cross over design with random allocation to drug or placebo group. The duration of the trial was 3 months with a 2 week run-in period and 2 week wash-oat period separating two treatment periods of 4 weeks each. A satisfactory response was obtained in 71.4% of migraineurs (p < 0.001) and 28.6% of patients with tension headache (p = N.S). Minor side effects were observed in 5 patients. Nifedipine is a useful agent for the management of migraine as it reduces frequency and severity of pain but the drug cannot be recommended for tension headache.

Adult↗
PubMed1995

Influence of human serum albumin content in formulations on the bioequivalency of interferon alfa-2a given by subcutaneous injection in healthy male volunteers.

To determine the influence of human serum albumin (HSA) content in formulations on the bioequivalency of recombinant interferon alfa-2a, a double-blind, randomized, two-way crossover study was conducted in 24 healthy male volunteers. Subjects received a single subcutaneous injection of 18 million IU of Roferon-A reconstituted with either the diluent containing 10 mg of HSA or the HSA-free diluent; final HSA contents in the 2 formulations were 15 mg and 5 mg, respectively. Administration of the 2 formulations resulted in similar 48-hour Roferon-A serum concentration-time profiles and comparable frequency and intensity of adverse events. The statistical analysis using the two one-sided tests procedure showed that both formulations were bioequivalent for pharmacokinetic parameters such as Cmax, tmax, AUC48, and AUC. We conclude that a threefold change in HSA content in formulations does not alter the bioequivalency of Roferon-A.

Adult↗
PubMed1991

Effects of pinacidil on detrusor instability in men with bladder outlet obstruction.

In a double-blind, crossover study the effect of the potassium channel opener pinacidil (N''-cyano-N'4-pyridyl-N-1,2,2-trimethylpropylguanidine monohydrate) at 25 mg. per day was evaluated in 10 patients with detrusor instability and bladder outlet obstruction. Nine patients completed the study: in 7 pinacidil was without significant effect on urodynamic variables and in 2 detrusor instability was not found at the end of the pinacidil period. Maximum urinary flow, frequency and nocturia were unchanged during pinacidil treatment, compared to the initial test and the placebo period. There was a significant decrease in standing blood pressure but heart rate was stable throughout the study. No patient experienced distinct symptomatic improvement or side effects during pinacidil treatment. The results suggest that pinacidil at the dosage given is not effective for treatment of unstable detrusor contractions associated with bladder outflow obstruction.

Administration, Oral↗
PubMed1993

Pharmaco-EEG mapping of diazepam effects using different references and absolute and relative power.

The effects of diazepam on the EEG were studied by means of EEG topographic mapping, using recordings with four different references. Subjects were ten healthy, right-handed, male volunteers aged 21-25 years. Double-blind crossover trials with a single oral dose of 10 mg diazepam and placebo controls were conducted in random sequence at intervals of one week. Four referential derivations--ipsilateral earlobe (A1A2), average reference (AV), source derivation (SD), and balanced noncephalic electrode (BNE)--were used. One-minute vigilance-controlled EEGs before drug administration and two hours after drug administration were analyzed using Fourier transformation; absolute power and relative power were calculated for four frequency bands. Diazepam caused a widespread increase of beta-frequency relative power, and a widespread decrease of theta-frequency absolute power when A1A2 and SD were taken as references. From the comparison of different reference electrodes we conclude that the selection of the reference and of spectral parameters (absolute power or relative power) play an important role in pharmaco-EEG studies.

Adult↗
PubMed2001

Antiarrhythmic drug use in the implantable defibrillator arm of the Antiarrhythmics Versus Implantable Defibrillators (AVID) Study.

BACKGROUND: Previous retrospective or observational series suggest that many patients with an implantable cardioverter-defibrillator (ICD) will be treated with antiarrhythmic drugs (AADs) to modify the frequency or manifestation of recurrent ventricular arrhythmias. The relative clinical benefit, however, is uncertain, and deleterious interactions can occur. The objective of this clinical investigation was to study the need for, and effects of, concomitant AAD use with the ICD in a prospectively defined cohort. METHODS: All patients randomly assigned to the ICD arm of the Antiarrhythmics Versus Implantable Defibrillators (AVID) study were followed for the addition of class I or III AADs ("crossover") after hospital discharge. Addition of AADs was strictly regulated by AVID protocol. The timing and reasons for crossover and the effects on ventricular arrhythmia recurrence were analyzed. Patients were excluded if they required AADs before hospital discharge after index arrhythmias or if they had no ventricular arrhythmia before initiation of AADs. RESULTS: After a median follow-up of 135 days, 81 (18%) of the 461 eligible patients required AADs and formed the crossover group. The primary reason for crossover was frequent ICD shocks in 64% of patients. The most common AAD selected was amiodarone (in 42%). Independent predictors of crossover were lower ejection fraction, absence of ventricular fibrillation, or presence of nonsyncopal ventricular tachycardia at presentation, prior unexplained syncope, female sex, and history of cigarette smoking. Before AAD use, the 1-year arrhythmia event rate was 90%; after AAD, the event rate was only 64% (P =.0001). The time to first event was extended from 3.9 +/- 0.7 months to 11.2 +/- 1.8 months. There were 1.4 +/- 3.7 fewer ICD therapy events (P =.005) after crossover, predominantly accounted for by reduction in shocks rather than antitachycardia pacing therapies. CONCLUSIONS: The majority of patients who receive ICDs for sustained ventricular tachycardia or ventricular fibrillation can be treated without AADs. Most commonly, AADs are added to combat frequent ICD shocks, which are successfully reduced by AAD therapy.

Aged↗
PubMed2003

Efficacy and tolerability of Boswellia serrata extract in treatment of osteoarthritis of knee--a randomized double blind placebo controlled trial.

Osteoarthritis is a common, chronic, progressive, skeletal, degenerative disorder, which commonly affects the knee joint. Boswellia serrata tree is commonly found in India. The therapeutic value of its gum (guggulu) has been known. It posses good anti-inflammatory, anti-arthritic and analgesic activity. A randomized double blind placebo controlled crossover study was conducted to assess the efficacy, safety and tolerability of Boswellia serrata Extract (BSE) in 30 patients of osteoarthritis of knee, 15 each receiving active drug or placebo for eight weeks. After the first intervention, washout was given and then the groups were crossed over to receive the opposite intervention for eight weeks. All patients receiving drug treatment reported decrease in knee pain, increased knee flexion and increased walking distance. The frequency of swelling in the knee joint was decreased. Radiologically there was no change. The observed differences between drug treated and placebo being statistically significant, are clinically relevant. BSE was well tolerated by the subjects except for minor gastrointestinal ADRs. BSE is recommended in the patients of osteoarthritis of the knee with possible therapeutic use in other arthritis.

Administration, Oral↗
PubMed2004

A systematic review of the effects of estrogens for symptoms suggestive of overactive bladder.

OBJECTIVE: To perform a systematic review of the effects of estrogen therapy on symptoms suggestive of overactive bladder (OAB) in postmenopausal women. MATERIALS AND METHODS: This analysis involved a literature review of Medline, Excerpta Medica, and the Science Citation Index and a manual search of popular urology, gynecology, gerontology, and primary care medicine journals from January 1969 to December 1999. Articles had to include estrogen and placebo treatment groups, published or original data presented at a scientific meeting and report symptoms suggestive of OAB. This search identified 11 randomized trials and included a total of 430 subjects. Thirty-six subjects who participated in two crossover studies received both estrogen and placebo and thus are counted twice, therefore 236 received estrogen therapy and 230 were placebo controls. Estrogen was administered systemically or locally as estriol, estradiol, conjugated estrogen, or estradiol and estriol. A meta-analysis of these studies was performed for all estrogen therapies and then separately for systemic and local therapies. RESULTS: Overall, estrogen therapies were associated with statistically significant improvements in all outcome variables: diurnal frequency (P = 0.0011), nocturnal frequency (P = 0.0371), urgency (P = 0.0425), number of incontinence episodes (P = 0.0002), first sensation to void (P = 0.0001), and bladder capacity (P = 0.0018). Local therapies had statistically significant beneficial effects on all outcome variables. However, systemic therapies were only associated with significant improvements in incontinence episodes and first sensation to void while nocturnal frequency actually worsened. CONCLUSION: Estrogen therapy may be effective in alleviating the symptoms suggestive of OAB. Local administration may be the most beneficial route of administration.

Cross-Over Studies↗
PubMed1995

Mechanisms of constipation in older persons and effects of fiber compared with placebo.

OBJECTIVE: To investigate the mechanisms of constipation and the effect of fiber supplementation on physiology, mechanisms, stool parameters, and colonic transit times in a group of constipated older patients. DESIGN: Single-blind, randomized, placebo-controlled fiber intervention with crossover. SETTING: A university-based outpatient center. PATIENTS: Ten community-living older men and women, healthy except for chronic constipation. INTERVENTIONS: Patients were given either 24 g psyllium fiber or placebo fiber daily for 1 month, then crossed over to the other arm for an additional month. Structured testing, including total gut transit time and rectal and colonic manometry, was performed at the end of each intervention month. Patients recorded stool frequency, consistency, and weights daily. RESULTS: The predominant mechanism for constipation in these patients was outlet delay caused by pelvic dyssynergia. Fiber decreased total gut transit time from 53.9 hours (placebo condition) to 30.0 hours (P < .05). Stool weights and consistency were not significantly improved by fiber, though there was a trend toward an increase in stool frequency (1.3 vs 0.8 bowel movements per day.) Pelvic floor dyssynergia was not remedied by fiber, even when constipation was clinically improved. CONCLUSIONS: Fiber supplementation appeared to benefit constipated older patients clinically, and it improved colonic transit time, but it did not rectify the most frequent underlying abnormality, pelvic floor dyssynergia.

Aged↗
PubMed2001

Insertion-duplication mutagenesis of neisseria: use in characterization of DNA transfer genes in the gonococcal genetic island.

We created plasmids for use in insertion-duplication mutagenesis (IDM) of Neisseria gonorrhoeae. This mutagenesis method has the advantage that it requires only a single cloning step prior to transformation into gonococci. Chromosomal DNA cloned into the plasmid directs insertion into the chromosome at the site of homology by a single-crossover (Campbell-type) recombination event. Two of the vectors contain an erythromycin resistance gene, ermC, with a strong promoter and in an orientation such that transcription will proceed into the cloned insert. Thus, these plasmids can be used to create insertions that are effectively nonpolar on the transcription of downstream genes. In addition to the improved ermC, the vector contains two copies of the neisserial DNA uptake sequence to facilitate high-frequency DNA uptake during transformation. Using various chromosomal DNA insert sizes, we have determined that even small inserts can target insertion mutation by this method and that the insertions are stably maintained in the gonococcal chromosome. We have used IDM to create knockouts in two genes in the gonococcal genetic island (GGI) and to clone additional regions of the GGI by a chromosome-walking procedure. Phenotypic characterization of traG and traH mutants suggests a role for the encoded proteins in DNA secretion by a novel type IV secretion system.

Chromosomes, Bacterial↗
PubMed1985

Effect of bepridil in patients with chronic stable angina: results of a multicenter trial.

The effects of bepridil, a calcium antagonist with a half-life of approximately 42 hr, were assessed in a double-blind, randomized, placebo-controlled crossover trial. Forty-four patients (39 men, five women) with exercise-induced angina pectoris and ST segment depression with exercise testing (modified Bruce protocol) were studied. Compared with placebo bepridil (400 mg daily) increased total exercise time, time to onset of angina, time to 1 mm of ST segment depression, time to 2 mm of ST segment depression, and total work achieved (all p less than or equal to .001). Both frequency of angina and nitroglycerin consumption decreased during the bepridil compared with the placebo period (p = .02 and .03, respectively). Minor side effects were noted during both the bepridil and placebo phases. Four patients experienced side effects that limited therapy (dizziness in three and abnormal results of liver function tests in one) and one patient died during the bepridil phase. This study suggests that bepridil, 400 mg daily, is effective for the treatment of exercise-induced myocardial ischemia and angina pectoris.

Angina Pectoris↗
PubMed1992

The paraphilias: a multiplicity of deviant behaviours.

The DSM-II and DSM-III both allow for multiple diagnoses. The DSM-III acknowledges that a patient may have multiple paraphilias but the true nature and extent of the multiplicity has only been documented recently. In order to study the degree of crossover between the various paraphiliac acts, a study of men who admitted to at least one paraphilia was conducted. A proportional index of multiple deviation was obtained. In addition, the mean number of admitted sexually deviant incidents per paraphilic category was computed as an estimate of the extent of deviant acts committed by this population. The results indicated that paraphiliacs tend to have multiple types of sexual aberrations as well as a high frequency of deviant acts per individual.

Adult↗
PubMed1993

Essential fatty acids in the treatment of premenstrual syndrome.

OBJECTIVE: To determine whether essential fatty acids are effective in the treatment of premenstrual syndrome (PMS). METHODS: In a randomized, double-blind, crossover trial, we studied 27 women diagnosed with PMS over ten menstrual cycles and 22 symptom-free controls over one cycle. The first cycle was used for diagnostic assessment. For the women with PMS, placebos were administered during the second cycle. This was followed by randomization to four cycles of active treatment with essential fatty acids and four cycles of placebo, with a crossover after completion of the fourth cycle. Assessment of symptoms and diagnosis of PMS were based on daily self-ratings made by the women throughout the study. RESULTS: Treatment with essential fatty acids did not reduce premenstrual symptoms or symptom cyclicity. However, time had a significant effect on a number of symptoms, indicating either a placebo effect or an effect from participation in the study. Women with PMS had a significantly higher frequency of dysmenorrhea and familial PMS than did the symptom-free controls. CONCLUSION: Treatment with essential fatty acids is ineffective therapy for PMS. The improvement we observed over time can be ascribed to either a placebo effect or participation in the study.

Adult↗
PubMed2000

Antifibrinolytics for heavy menstrual bleeding.

BACKGROUND: Heavy menstrual bleeding (HMB) is an important cause of ill health in women. Medical therapy, with the avoidance of possibly unnecessary surgery, is an attractive treatment option. A wide variety of medications are available to reduce heavy menstrual bleeding but there is considerable variation in practice and uncertainty about the most appropriate therapy. Plasminogen activators are a group of enzymes that cause fibrinolysis (the dissolution of clots). An increase in the levels of plasminogen activators has been found in the endometrium of women with heavy menstrual bleeding compared to those with normal menstrual loss. Plasminogen activator inhibitors (antifibrinolytic agents) have therefore been promoted as a treatment for heavy menstrual bleeding. There has been a reluctance to prescribe tranexamic acid due to possible side effects of the drugs such as an increased risk of thrombogenic disease (deep venous thrombosis). Long term studies in Sweden, however, have shown that the rate of incidence of thrombosis in women treated with tranexamic acid is comparable with the spontaneous frequency of thrombosis in women. OBJECTIVES: To determine the effectiveness of antifibrinolytics in achieving a reduction in heavy menstrual bleeding. SEARCH STRATEGY: All studies which might describe randomised controlled trials of antifibrinolytic therapy for the treatment of heavy menstrual bleeding were obtained by electronic searches of the MEDLINE 1966-1997, EMBASE 1980-1997 and the Cochrane Library. Companies producing antifibrinolytics and experts within the field were contacted for reference lists and information on unpublished trials. SELECTION CRITERIA: Randomised controlled trials in women of reproductive age treated with antifibrinolytic agents versus placebo, no treatment or any other medical (non-surgical) therapy for regular heavy menstrual bleeding within either the primary, family planning or specialist clinic settings. Women with post menopausal bleeding, intermenstrual bleeding, iatrogenic or pathological causes of heavy menstrual bleeding were excluded. DATA COLLECTION AND ANALYSIS: Fifteen eligible trials were assessed by three reviewers and eight of these did not meet with the inclusion criteria. Of the seven remaining trials, four of these could be included within the meta-analysis. The remaining three trials had a crossover design and despite contacting the authors and appropriate companies, we were unable to extract the results in a format suitable to include these within the meta-analysis. However the results are included within the text of the review for discussion. MAIN RESULTS: Antifibrinolytic therapy compared to placebo showed a significant reduction in mean blood loss (WMD -94.0 [-151.4, -36.5]) and significant change in mean reduction of blood loss (WMD -110.2 [-146. 5, -73.8]). This objective improvement was not mirrored by a patient perceived improvement in monthly menstrual blood loss (RR 2.5 [0.9, 7.3]) in the one study which recorded this outcome ( approximately approximately Edlund 1995 approximately approximately ). Antifibrinolytic agents were compared to only three other medical (non-surgical) therapies: mefenamic acid, norethisterone administered in the luteal phase and ethamsylate. In all instances, there was a significant reduction in mean blood loss (WMD -73.0 [-123.4, -22.6], WMD -111.0 [-178.5, -43.5] and (WMD -100 [-143.9, -56.1] respectively) and a strong, although non-significant trend in favour of tranexamic acid in the participants' perception of an improvement in menstrual blood loss. There were no significant differences in the frequency of reported gastrointestinal side effects with tranexamic acid when compared to either NSAIDs (RR 0.9 [0.4, 2.1], oral luteal phase progestagens (RR 0.4 [0.1, 1.2]) or ethamsylate (RR 0.88 [0.3, 2.9]) when these treatments were used for heavy menstrual bleeding. (ABSTRACT TRUNCATED)

Antifibrinolytic Agents↗
PubMed1982

[Effect of a long-acting analgesic, buprenorphine on cancer pain--a single-blind crossover comparison with pentazocine].

The therapeutic value of buprenorphine was investigated in 31 patients suffering from moderate to severe cancer pain by intramuscular administration at the single doses of 0.2 mg and 0.3 mg in comparison with pentazocine 30 mg. Analgesic effect of buprenorphine 0.3 mg was significantly superior to buprenorphine 0.2 mg and pentazocine 30 mg. The duration of analgesia with buprenorphine was 9 hours at 0.2 mg and 11 hours at 0.3 mg, which were markedly longer than pentazocine's 6 hours. Side effects most commonly observed in the three groups were nausea, vertigo, oral dryness, urinary retention, vomiting, sweating, and headache. The frequency of side effects was 54.8% for buprenorphine 0.2 mg, 50.0% for buprenorphine 0.3 mg and 58.3% for pentazocine 30 mg respectively, indicating no significant difference between the three groups. Blood pressure, heart rate and respiratory rate did not change appreciably, thereby suggesting a little effect of buprenorphine on the respiratory and cardiovascular systems. Buprenorphine was found a useful or extremely useful in 58% at 0.2 mg and 87.5% at 0.3 mg. As the result it was concluded that buprenorphine could be valuable as an analgesic for cancer pain.

Adolescent↗
PubMed1982

Mexiletine, a new antiarrhythmic agent, for treatment of premature ventricular complexes.

This double-blind crossover study was designed to compare the safety and efficacy or mexiletine, a new class I antiarrhythmic agent, with those of a placebo in reducing premature ventricular complexes. Twelve patients who had a median of 294 such complexes/hour were admitted to the study. Eleven completed 4 weeks of trial with mexiletine and placebo with ambulatory electrocardiographic (Holter) recordings taken at the end of each treatment period. The doses given were designed to reduce the frequency of premature ventricular complexes by 50 percent or more from the baseline value. Mexiletine significantly reduced the rate of premature ventricular complexes by comparison with placebo (-66 percent versus 3 percent, p = 0.032). In addition, mexiletine reduced the median number/hour of ventricular couplets observed. After 4 weeks of therapy, 2, 2, 1 and 6 patients, respectively, were taking 100, 200, 300 and 400 mg of mexiletine every 8 hours. Mexiletine produced no significant change in baseline values including electrocardiographic intervals, blood pressure or heart rate. The most frequently observed adverse effects were digestive difficulties (eight patients taking mexiletine, four taking placebo) and central nervous system effects (seven taking mexiletine, five taking placebo). These data show the efficacy and safety of mexiletine in the treatment of premature ventricular complexes in a majority of patients.

Aged↗
PubMed2000

Effects of diltiazem retard on ambulatory blood pressure and heart rate variability in patients with essential hypertension.

BACKGROUND: Dihydropyridine calcium antagonists increase heart rate due to reflex activation of the sympathetic nervous system, although these effects are less obvious for long-acting agents. OBJECTIVE: To study the effects of diltiazem retard, a long-acting nondihydropyridine calcium antagonist, on 24h blood pressure, heart rate and autonomic nerve activity in patients with essential hypertension. DESIGN: Randomized crossover design. METHODS: Thirteen patients [five men and eight women, aged 64+/-2 years (mean+/-SEM)] were administered placebo or diltiazem retard (100-200mg once daily) for 4 weeks each. Ambulatory monitoring of blood pressure and heart rate, and electrocardiography were carried out at the end of each period using a multibiomedical recorder (TM-2425). Autonomic nerve activity was evaluated by power spectral analysis of variability of heart rate using the high-frequency component as an index of parasympathetic nerve activity and the ratio of the low-frequency component and the high-frequency component as an index of sympathovagal balance. RESULTS: Treatment with diltiazem retard significantly decreased 24h average blood pressure and heart rate by 11.6+/-3.6/5.7+/-1.8mmHg and 5.0+/-1.1 beats/min, respectively. The changes in daytime and night-time values were comparable. Diltiazem retard also significantly decreased daytime and 24h low:high-frequency-component ratio (2.0+/-0.2 versus 1.7+/-0.2 and 1. 8+/-0.2 versus 1.6+/-0.2, respectively). CONCLUSIONS: These results indicate that diltiazem retard is effective as a once-daily antihypertensive agent and has favorable effects on heart rate and the autonomic nervous system.

Aged↗