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Blood glucose control and glomerular capillary basement membrane thickening in experimental diabetes.

Glomerular capillary basement membrane thickness (BMT) was measured in 23 rats which had had streptozocin-induced diabetes for 14 months and in 12 age-matched controls. Diabetic rats were randomly allocated to different groups, either receiving no treatment or treated with a low carbohydrate diet or insulin, or both. Control rats were randomly allocated to a normal or low carbohydrate diet. Among the diabetic rats mean plasma glucose concentrations for the groups ranged from 27-4 mmol/l (494 mg/100 ml) in the untreated rats to 9-8 mmol/l (177 mg/100 ml) in those receiving both a low carbohydrate diet and insulin. A highly significant positive relation was found between BMT and plasma glucose concentration for individual rats. When BMT was corrected for body weight a similar relation was observed.

Animals

Moderate alcohol intake and heart rate variability adaptations to high-intensity interval training in healthy young adults: the BEER-HIIT study.

BACKGROUND: It is unknown whether daily alcohol consumption influences training effects on heart rate variability (HRV). This study investigated: (i) the effects of a 10-week high-intensity interval training (HIIT) on HRV in healthy young adults; and (ii) the effects of daily alcohol consumption on HRV responses to exercise. METHODS: 71 healthy young adults (18-40 years old; 52.1% women) participated in the BEER-HIIT study. We conducted a 10-week (2 days/week) controlled trial (ClinicalTrials.gov ID: NCT03660579). Participants were allocated to 5 groups: a non-training group (N-T) and four HIIT groups. Participants in the training groups chose whether to consume alcohol. Those choosing alcohol were randomly allocated to receive beer (5.4%; T-Beer) or an equivalent amount of alcohol (vodka; T-Ethanol) in sparkling water. Those choosing no alcohol were randomly allocated to receive alcohol-free beer (0.0%; T-Zero) or sparkling water (T-Water). Training comprised eight weight-bearing exercises performed in circuit form. HRV was measured before and after the intervention. RESULTS: No statistically significant between-group differences in HRV outcomes were detected after the intervention (all p > 0.05). CONCLUSIONS: Our findings indicate that: (i) no statistically significant differences in HRV responses were detected following a 10-week HIIT program using weight-bearing exercises performed twice per week; and (ii) no statistically significant differences in HRV responses were observed among the assigned beverage intervention groups. These findings should be interpreted cautiously because HRV was a secondary outcome and the study was not specifically powered to detect differences in these parameters.

alcohol

Effects of skirting on processing characteristics of Targhee wool.

Ninety mature Targhee ewes were randomly allocated to nine lots. Lots were randomly assigned to three fleece preparation treatments: 1) nonskirted (control); 2) bellies removed, in which bellies and topknots were removed on the shearing floor; and 3) skirted, in which bellies and topknots were removed and remaining fleece was thrown on a table and lightly skirted. Bellies and topknots composed about 6 to 7% of the fleece weight. An additional 6.6% was removed when fleeces were skirted. Top fiber diameters were not affected (P greater than .10) by skirting. Although not significant (P greater than .10), percentage yield, vegetable content, percentage of noilage, top fiber length, and yellowness indexes tended to be most desirable for skirted lots and least desirable for unskirted lots. Lots with bellies removed were intermediate. Removal of bellies reduced vegetable contamination by 8.4%, with an additional reduction of about .5% by further skirting. Skirting reduced the number of fibers less than 25.4 mm (P less than .10) by 42%. Minimal colored fiber contamination of top was observed. One colored fiber per 15 g of top was detected in two lots of the treatment with bellies removed. All other lots contained no colored fibers. All wools evaluated were well below industry limits set for use in high-quality white or pastel fabrics. All skirted lots of wool evaluated in this study had improved processing characteristics for all processing traits evaluated.

Animal Husbandry

Combined luteinizing hormone releasing hormone analogue and exogenous gonadotrophins for the treatment of infertility associated with polycystic ovaries.

This study was designed to compare the results of treatment with, firstly, exogenous gonadotrophins, with (57 cycles) and without (65 cycles) pretreatment with a superactive analogue of luteinizing hormone releasing hormone (LHRH) and, secondly, pure follicle stimulating hormone (FSH) (50 cycles) with those of human menopausal gonadotrophin (HMG) (72 cycles) in 46 women with clomiphene-citrate-resistant anovulation associated with polycystic ovaries. Patients randomly allocated to the analogue group received buserelin (Suprefact, Hoechst, UK, Ltd, Hounslow, Middlesex), 800 micrograms/day by nasal insufflation and when hypogonadism was achieved, patients were again randomly allocated for ovarian stimulation with either FSH or HMG. Controls received FSH or HMG alone. Patients pretreated with the analogue had similar pregnancy and ovulation rates, needed larger doses and more days of gonadotrophin therapy and had more ovarian overstimulation than those receiving no pretreatment. The role of superactive LHRH analogues for induction of a single ovulation for in-vivo fertilization is thus uncertain. Pure FSH had no advantages over HMG, the LH content of HMG having no deleterious effect on the ovary.

Adult

A headache protocol for nurses: effectiveness and efficiency.

To test the effectiveness and efficiency of a nurse-administered protocol for headache in the primary care setting, we conducted a prospective controlled trial. Two hundred three randomly allocated patients were evaluated by nurses using the protocol who managed independently 55.2% of the patients and received physician consultation on the others. A total of 193 patients were randomly allocated to the physician-control group. Nurse-protocol group patients experienced equivalent symptomatic relief and expressed significantly greater satisfaction with the care they had received than did patients in the physician-control group. A retrospective study of the presenting findings in patients with serious diseases of the CNS provided evidence supporting the safety of the protocol logic. We conclude that nurse-protocol management of headache in this primary care practice was effective and efficient.

Ambulatory Care

Randomised controlled trial of day and in-patient psychiatric treatment. 2: Comparison of two hospitals.

Acutely ill patients presenting for admission in two district psychiatric services were randomly allocated to day-hospital or in-patient care. In both services a quarter of all admissions could not be allocated because they were too ill (half of these were compulsory admissions); these patients were predominantly manic and schizophrenic patients with pronounced psychotic symptoms and disturbed behaviour. In one service 80% (41/51) of patients randomly allocated to day-hospital treatment were successfully engaged in treatment compared with 54% (19/35) in the other service. This difference arose because only patients with mildly disturbed behaviour could be treated at the second day hospital. For patients who were successfully allocated, the outcome of treatment was similar in terms of psychiatric symptoms and social functioning. The results of a treatment trial for acutely ill patients in one district service cannot be generalised to other district services without due attention to the factors, such as staffing levels, which determine the degree of disturbed behaviour that can be tolerated in the day hospital.

Acute Disease

UK Prospective Diabetes Study (UKPDS). VIII. Study design, progress and performance.

The UK Prospective Diabetes Study (UKPDS) is a multi-centre, prospective, randomised, intervention trial of 5100 newly-diagnosed patients with Type 2 (non-insulin-dependent) diabetes mellitus which aims to determine whether improved blood glucose control will prevent complications and reduce the associated morbidity and mortality. Newly presenting Type 2 diabetic patients aged 25-65 years inclusive, median age 53 years, median body mass index 28 kg/m2 and median fasting plasma glucose 11.3 mmol/l, were recruited and treated initially by diet. Ninety five percent remained hyperglycaemic (fasting plasma glucose greater than 6 mmol/l) and were randomly allocated to different therapies. In the main randomisation, those who were asymptomatic and had fasting plasma glucose under 15 mmol/l were allocated either to diet policy, or to active policy with either insulin or sulphonylurea aiming to reduce the fasting plasma glucose to under 6 mmol/l. Over 3 years, the median fasting plasma glucose in those allocated to diet policy was 8.9 mmol/l compared with 7.0 mmol/l in those allocated to active policy. The Hypertension in Diabetes Study has been included in a factorial design to assess whether improved blood pressure control will be advantageous. Patients with blood pressure greater than or equal to 160/90 mm Hg were randomly allocated to tight control aiming for less than 150/85 mm Hg with either an angiotensin-converting enzyme inhibitor or a Beta-blocker or to less tight control aiming for less than 200/105 mm Hg. The endpoints of the studies are major clinical events which affect the life and well-being of patients, such as heart attacks, angina, strokes, amputations, blindness and renal failure. To date, 728 patients have had at least one clinical endpoint. Surrogate endpoints include indices of macrovascular and microvascular disease detected by ECG with Minnesota Coding, retinal colour photography and microalbuminuria. The studies also aim to evaluate potential risk factors for the development of diabetic complications such as smoking, obesity, central adiposity, plasma LDL- and HDL-cholesterol, triglyceride, insulin, urate and other biochemical variables. The studies are planned to terminate in 1994, with a median follow-up of 9 years (range 3-16 years) for the glucose study and 5 years (range 2-6 years) for the hypertension study.

Adult

Nurse-protocol management of low back pain. Outcomes, patient satisfaction and efficiency of primary care.

To test the validity of a nurse-administered protocol for low back pain, a prospective trial of 419 patients was undertaken in a walk-in clinic. In all, 222 patients were randomly allocated to a "nurse-protocol group" in which they were evaluated by one of five nurses using the protocol; the nurses independently managed 53 percent of the patients and referred to a physician patients with potentially complex conditions. In addition, 197 patients in a randomly allocated control group were managed by one of 32 physicians. Care in the experimental and control groups was compared by follow-up telephone contact and by a four-month chart review. There was no significant difference in symptomatic relief or the development of serious disease in the two groups. Nurse-protocol patients expressed greater satisfaction with the care they had received; patient satisfaction correlated positively with symptom relief. In over 95 percent of the patients, there were noncomplex, nonserious, nonchronic conditions as the cause of back pain. We conclude that nurse-protocol management of this generally benign condition in a primary care setting is both effective and efficient.

Adolescent

Effect of suture technique on early healing of intestinal anastomoses in rats.

OBJECTIVE: To see if the site and tension of sutures had any influence on early breaking strength in intestinal anastomoses. MATERIAL: 161 Male Wistar rats. INTERVENTIONS: First experiment: after laparotomy and division of the ileum an inverted end to end anastomosis was made in a single layer with 14 interrupted sutures of 7/0 polypropylene. All sutures were inserted 3 mm from the cut edges. The rats were randomly allocated to one of four groups according to the size of the loop of suture used: tight (n = 38), 0.4 mm (n = 22), 0.9 mm (n = 35), or 2.0 mm (n = 24). Second experiment: the method used was the same except that sutures were placed 1.5 mm from the cut edges and the rats were randomly allocated to one of two groups according to the size of loop of suture--tight (n = 20), or 0.9 mm (n = 22). MAIN OUTCOME MEASURES: Breaking strength measured in a tensiometer (both experiments); and myeloperoxidase activity/g tissue, hydroxyproline content and solubility/biopsy specimen (first experiment only). RESULTS: Breaking strength decreased proportionally the tighter the sutures were tied, and the differences were significantly greater when the sutures were placed closer to the cut edges. Anastomotic myeloperoxidase activity, hydroxyproline content, and soluble: total hydroxyproline ratio were similar in all groups. CONCLUSION: Tight sutures may promote proteolytic tissue degradation by reducing the local availability of circulating proteinase inhibitors.

Anastomosis, Surgical

Pilonidal sinus: a claim for simple track incision.

Ninety-six patients treated surgically for pilonidal sinus were examined in a two-part study. In the first part, 36 patients were randomly allocated according to the surgical techniques employed: marsupialization, incision, and excision without primary closure. Healing times and recurrences a year after operation were studied. The healing times of patients treated by excision were longer in comparison with those treated by incision or marsupialization. The recurrence rates were similar for all techniques used. In the second part of the study 60 patients were randomly allocated according to times of returning to work. Twenty-nine of these patients returned to work before their wound healed; 31 resumed work a week after epithelization of the wound. The wounds healed more quickly in patients who started working before they were closed. Incision of the sinus track, carried out using local anesthesia in the outpatient clinic, allowed the patient to return to work without pain sooner.

Anesthesia, Local

Treatment of atopic dermatitis with antihistamines: lessons from a single-patient, randomized clinical trial.

BACKGROUND: Single-patient randomized clinical trials (RCTs) can be utilized to maintain methodologic precision in the analysis of treatment effect in individual patients. We describe the results of a single-patient RCT in a patient with atopic dermatitis and review practical considerations regarding the use of antihistamines. METHODS: Using double-blind, crossover techniques, the patient was randomly allocated to four 2-week treatment periods with the following regimens: chlorpheniramine, 8 mg twice daily; chlorpheniramine, 12 mg twice daily; terfenadine, 120 mg twice daily; and placebo (phase 1). The drug that produced superior results from phase 1 (chlorpheniramine, 8 mg) was subsequently compared with astemizole, 10 mg/d, during phase 2, consisting of four 4-week, double-blind, crossover trial periods with random allocation of study drugs. Daily symptom scores, as well as end of treatment period summary impressions by patient and investigator, were analyzed. RESULTS: In both phases, chlorpheniramine produced the most noticeable positive therapeutic effect on the patient's mild but most disturbing symptoms (pruritus and eye irritation) associated with atopic dermatitis. Drowsiness was reported with chlorpheniramine. Tolerance to this side effect, however, developed quickly. CONCLUSIONS: A single-patient RCT with different antihistamines in a patient with chronic atopic dermatitis was a useful tool in achieving a favorable balance among efficacy, toxicity, and cost of therapy.

Adult

A double blind, randomised, multicentre comparison of two doses of intravenous iloprost in the treatment of Raynaud's phenomenon secondary to connective tissue diseases.

OBJECTIVE: To compare low (0.5 ng/kg/min) and standard dose (2 ng/kg/min) iloprost (a stable carbacyclin analogue of prostacyclin) in patients with Raynaud's phenomenon secondary to connective tissue disorders. DESIGN: Double blind, random allocation, three six hour infusions on consecutive days. Follow up period eight weeks. SETTING: Rheumatology units, five teaching hospitals. PATIENTS: 55 Patients with Raynaud's phenomenon (greater than seven attacks per week), 32 secondary to well documented classical progressive systemic sclerosis (American Rheumatism Association criteria), 11 CREST syndrome, 5 mixed connective tissue disease, 1 rheumatoid arthritis, 1 Sjögren's syndrome, 1 childhood dermatomyositis, and 4 abnormal nailfold capillaroscopy and antibody profiles but no definite diagnosis. INTERVENTIONS: All other treatment for Raynaud's phenomenon was discontinued two weeks before entry. 28 Patients were randomly allocated to receive the low dose, 27 the standard dose. Differing dilutions allowed infusion rates to be started at 10 ml/h with increments of 10 ml/h every 15 minutes until infusion rates reached 0.5 ng/kg/min and 2 ng/kg/min respectively. MAIN OUTCOME MEASURE(s)--Reduction in frequency, duration, and severity of attacks of Raynaud's phenomenon. Assessment of ulcer and ischaemic lesion healing. RESULTS: Both dosage regimens were equally effective in reducing severity, frequency, and duration of Raynaud's attacks. Ulcer healing occurred to similar degree in both treatment groups (standard dose 44%, low dose 39%). Low dose was associated with significantly fewer side effects. CONCLUSIONS: Both dosage regimens reduce severity of Raynaud's phenomenon and encourage ulcer healing. Low dose was associated with fewer side effects and was better tolerated by the patients.

Adult

Effects of lorazepam on psychomotor performance: a comparison of independent-groups and repeated-measures designs.

The purpose of this study was to compare the sensitivity to the effects of lorazepam (2.5 mg) of a design using independent groups (random allocation of subjects to either a placebo or a lorazepam treatment) with a repeated-measures design (subjects tested both before and after lorazepam treatment). With both designs, it was possible to demonstrate significant and equal effects of lorazepam in tests based upon speed of responding: Lorazepam significantly increased simple reaction time and significantly decreased performance in number cancellation and symbol copying tasks. The independent-groups design was more sensitive (i.e., showed effects at a higher level of significance) to the lorazepam-induced impairment in episodic memory, as assessed in a picture recognition task, and to the lorazepam-induced impairment in a word completion task. Comparisons between the two control condition scores indicated that there were unlikely to be significant group differences with random allocation of a relative homogeneous group of volunteers, such as medical students. While either design would be appropriate for homogeneous populations, for a heterogeneous clinical population where groups cannot be matched the repeated-measures design would be preferable.

Adult

Alternatives to randomization in surgical studies.

The purpose of randomization is to provide unbiased estimates of treatment effects and valid probability statements for hypothesis tests in comparative studies. Difficulties with randomized allocation of patients in surgical studies include: patient selection--due to protocol limitations, possible changes in referral patterns, the need for patient consent, and physician co-operation; disruption of the patient-physician relationship; static protocol not responsive to changes as surgical skill evolves and experience regarding patient selection is acquired; the larger number of patients required causes a longer study and more patients receiving what may be a worse therapy. Moreover, for evaluating a new heart valve, the primary purpose should be estimation rather than comparison with a current device. This can be accomplished faster, in a more generalizable way and with more concern for patient care by using non-randomized comparison groups.

Ethics, Medical

Relationship between the onset of oestrus, the preovulatory surge in luteinizing hormone and ovulation following oestrous synchronization and superovulation of farmed red deer (Cervus elaphus).

The timing of ovulation relative to the onset of oestrus and the preovulatory surge in luteinizing hormone (LH) was studied in red deer following treatments to synchronize oestrus and induce either a monovulatory or superovulatory response. Mature hinds (n = 36) were allocated randomly to two mating groups (n = 16 + 20), with respective treatments staggered by 4 weeks during the 1990 rut (March-April). Each hind was treated with an intravaginal controlled internal drug releasing (CIDR)-type S device for 14 days. Treatments to induce a monovulatory response included CIDR device alone (treatment A; n = 4 + 8) and additional injection of 200 iu pregnant mares' serum gonadotrophin (PMSG) at device removal (treatment B; n = 4 + 4). Treatments to induce a superovulatory response included injections of 200 iu PMSG and 0.5 units ovine follicle-stimulating hormone (FSH) at about time of removal of CIDR devices (treatment C; n = 4 + 4) and further treatment with gonadotrophin-releasing hormone (GnRH) analogue 18 h after removal of CIDR devices (treatment D; n = 4 + 4). The hinds were run with crayon-harnessed stags from insertion of CIDR devices (12 March or 9 April) and blood samples were taken every second day to determine plasma progesterone. Further blood samples were collected for determination of plasma LH and progesterone via indwelling jugular cannulae every 2 h for 72 h from removal of CIDR devices. Hinds were allocated randomly to an initial ovarian examination by laparoscopy at either 16 or 20 h (A and B), or 12 or 16 h (C and D) after the onset of oestrus, with laparoscopy repeated at intervals of 8 h until either ovulation was recorded (A and B), or for four successive occasions (C and D). All hinds received cloprostenol injections 15 days after device removal. A total of 28 hinds (78%) exhibited oestrus and a preovulatory LH surge, with mean (+/- SEM) times to onset of oestrus of 44.6 +/- 1.0 h (A; n = 7), 37.4 +/- 2.0 h (B; n = 7), 16.3 +/- 1.7 h (C; n = 6) or 14.0 +/- 1.7 h (D; n = 8). Failure to exhibit oestrus or LH surge was most prevalent among hinds in treatment A early in the rut.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals

Practice randomization and clinical research. The Indiana experience.

Thoughtful preparation of a research laboratory is an early step in designing a program for scientific investigation. The Division of General Internal Medicine at Indiana University has maintained a "laboratory" for outpatient clinical investigation for more than 15 years. In this report, we describe the structure and function of the General Medicine Practice in the Regenstrief Health Center on the campus of the Indiana University School of Medicine in Indianapolis. Specifically, we discuss the ongoing random allocation of subjects, the local resources for data management and tracking of patients' use of clinical services, and how combining this information system into a randomized primary care system has fostered successful ventures in clinical investigation.

Health Services Research

Efficacy of milbemycin oxime against experimentally induced Ancylostoma caninum and Uncinaria stenocephala infections in dogs.

Twenty-eight helminth-naive Beagles, 16 to 26 weeks old, were inoculated with 200 third-stage larvae each of Ancylostoma caninum and Uncinaria stenocephala 5 times at weekly intervals. Dogs were randomly allocated to 4 groups of 7 on the basis of fecal egg counts, and treatments were randomly assigned. Groups 1 and 3 were given milbemycin oxime at a dosage of 500 micrograms/kg of body weight, PO, on day 0 and on days 0 and 30, respectively; groups 2 and 4 were nontreated controls. Fecal egg counts were evaluated before and after treatments. Feces were collected daily for 7 days after the final treatment for recovery of worms passed, and all dogs were euthanatized 7 days after the final treatment for recovery of worms retained. A 65.7% reduction from the pretreatment value for geometric mean hookworm egg count was found 7 days after the first treatment, and a 97.1% reduction 7 days after the second treatment. Although milbemycin oxime had 96.5% and 99.5% controlled efficacy against A caninum after 1 or 2 treatments, respectively, it lacked efficacy against U stenocephala. The geometric mean number of U stenocephala and the total number of hookworms retained after 1 or 2 treatments were not significantly different from the numbers retained by the corresponding control groups.

Ancylostoma

[Therapeutic progress. Critical analysis of controled and non-controled clinical studies].

Methods used in the evaluation of therapeutic results in clinical oncology are criticized on the basis of recent examples of studies including the most-used antitumor agents. The need for random allocation of patients in comparative studies is underlined and the practical, statistical, and ethical limitations on randomization procedures are reviewed.

Ethics, Medical