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The optimal training load for the development of dynamic athletic performance.

This study was performed to determine which of three theoretically optimal resistance training modalities resulted in the greatest enhancement in the performance of a series of dynamic athletic activities. The three training modalities included 1) traditional weight training, 2) plyometric training, and 3) explosive weight training at the load that maximized mechanical power output. Sixty-four previously trained subjects were randomly allocated to four groups that included the above three training modalities and a control group. The experimental groups trained for 10 wk performing either heavy squat lifts, depth jumps, or weighted squat jumps. All subjects were tested prior to training, after 5 wk of training and at the completion of the training period. The test items included 1) 30-m sprint, 2) vertical jumps performed with and without a countermovement, 3) maximal cycle test, 4) isokinetic leg extension test, and 5) a maximal isometric test. The experimental group which trained with the load that maximized mechanical power achieved the best overall results in enhancing dynamic athletic performance recording statistically significant (P < 0.05) improvements on most test items and producing statistically superior results to the two other training modalities on the jumping and isokinetic tests.

Adult↗

[Treatment of duodenal ulcer with famotidine].

In a prospective double blind study the efficacy and safety of the new H2-receptor antagonist famotidine was compared with ranitidine. 48 patients with endoscopically proven duodenal ulcer were randomly allocated to receive famotidine 40 mg once at night, 20 mg bid, 40 mg bid or ranitidine 150 mg bid. After 4 weeks of treatment the ulcers of 7/12, 10/12, 9/12 and 6/12 patients were healed; the corresponding rates after 8 weeks were 9/12, 12/12, 11/12 and 10/12. Statistically there was no significant difference between the various groups. Adverse events of any clinical importance were not observed. These data indicate, that famotidine is as effective and as safe as ranitidine for the treatment of acute duodenal ulcer.

Anti-Ulcer Agents↗

Comparative studies of cefoxitin and cephalothin: an overview.

A comparative study of the efficacy and safety of cefoxitin and cephalothin in the treatment of serious infections was carried out by 21 investigators. A total of 320 patients were treated with cefoxitin, and 276 patients were treated with cephalothin. In each group 50% of patients could be evaluated. Patients were randomly allocated to groups in open fashion, and final analysis showed that the groups were comparable in terms of sex, age, severity of illness, and duration of therapy. The majority of pathogens isolated were susceptible to both agents, although 13% of gram-negative bacilli and anaerobes were susceptible to cefoxitin alone. The overall percentage of patients cured or improved by cephalothin was 93%; for cefoxitin the proportion was 91%. No statistical differences in response by type of organism or site of infection were shown. Cefoxitin was effective in treating infections and in eradicating the pathogenic bacteria. Cefoxitin was as well tolerated as cephalothin and produced no more adverse reactions or abnormal laboratory findings than did cephalothin. The results of this study demonstrate that cefoxitin is as effective in achieving bacteriologic and clinical cures as is cephalothin and also is effective in treatment of infections due to cephalothin-resistant bacteria.

Bacterial Infections↗

A controlled, prospective study to evaluate the effectiveness of a back school in the relief of chronic low back pain.

Ninety-two chronic low back pain patients were randomly allocated to two groups to evaluate the effectiveness of a back school compared with an exercise-only regimen according to specified outcome variables. The data from 78 patients with 7 years mean duration of symptoms was analyzed. Three assessments were made: before treatment and 6 and 16 weeks after treatment. Changes in patients' levels of pain, functional disability, and other related variables were compared in the two groups. Almost all variables showed an improvement at 6 weeks. At 16 weeks, functional disability and pain levels showed a significant difference. Back school patients continued to make an improvement. This method of managing low back pain makes maximal use of limited resources and appears to be effective, especially in the longer term.

Adolescent↗

Maintenance therapy of duodenal ulcer with famotidine. A multicenter United States study.

The decision to treat a patient with duodenal ulcer should be based upon the following: severity of disease; effectiveness of treatment; and risk and cost of treatment. A number of drugs are effective for this condition. When administration of the drug is discontinued, a recurrence of the ulcer occurs most often within three months, with the rate approaching 90 percent at one year. Maintenance therapy has evolved as a method of preventing recurrence. A double-blind, randomized, multicenter study was done to compare 40 mg of famotidine at bedtime, 20 mg of famotidine at bedtime, and placebo in the maintenance treatment of patients with recently healed duodenal ulcer. In 37 centers in the United States, 303 patients received randomly allocated treatment with 40 mg of famotidine at bedtime (107 patients), 20 mg of famotidine at bedtime (97 patients), or placebo (99 patients). The treatment groups were comparable as to the risk factors and other characteristics. Esophagogastroduodenoscopies were scheduled at three, six, and 12 months of treatment. Additional endoscopies could be done at any time if symptoms suggested a relapse. Cumulative relapse rates were significantly lower in the famotidine groups than in the placebo group at all time points (p less than 0.01). The cumulative life-table relapse rates at three, six, and 12 months were 9.2, 20.9, and 24.8 percent for the 40-mg famotidine group; 13.5, 16.1, and 23.3 percent for the 20-mg famotidine group; and 39.3, 51.5, and 56.8 percent for the placebo group. No significant difference between the two famotidine groups was observed. Within each period, the relapse rate was lower with famotidine than with placebo. Famotidine is more effective than placebo as maintenance therapy. It is generally well tolerated for periods of up to one year. A dose of 20 mg at bedtime is proposed as the maintenance dose. Fewer relapses occurred in non-smokers, in females, and in patients in whom healing occurred with placebo. More relapses occurred in patients under 40 years of age, patients with a long ulcer history, or patients who were younger than 40 years of age at onset of ulcer disease.

Adult↗

Cholesterol reduction following health screening in general practice.

OBJECTIVES: To evaluate changes in plasma cholesterol following health screening and health discussions in general practice. DESIGN: Randomised prospective population-based study conducted over a period of 5 years. SETTING: Primary care, all general practitioners (GPs) in a well-defined area. SUBJECTS: A random sample of inhabitants aged 30-49 years in January 1991, registered with a local GP was invited to participate. The participants (1507 persons, or 75.4% of the 2000 invited) were randomly allocated to two intervention groups and a control group. MAIN OUTCOME MEASURES: Plasma cholesterol, percentage of subjects with plasma cholesterol higher than 7 mmol/l. RESULTS: After 5 years of intervention, plasma cholesterol in the whole population was significantly lower in the intervention groups compared to the control group. The decrease was most pronounced (0.5 mmol/l) in subjects at high cardiovascular risk. The percentage of high-risk individuals with a cholesterol level higher than 7 mmol/l was significantly lower in the intervention groups compared to the control group (9.8% vs 6.2%, p = 0.04), corresponding to a 37% reduction. CONCLUSIONS: The study shows that the health checks had a measurable impact on plasma cholesterol levels, the most pronounced effect is seen among individuals at high cardiovascular risk.

Adult↗

Comparison of diflunisal and acetaminophen with codeine in the management of grade 2 ankle sprain.

The emergency physician treats many patients with mild to moderate pain due to musculoskeletal injury. The physician must consider the extent of injury, the patient's medication history, and the potential for abuse when prescribing an oral analgesic. A study was designed to compare the efficacy of two oral analgesics, one containing a narcotic and one nonnarcotic, in relieving mild to moderate pain associated with grade 2 ankle sprain. Forty patients were enrolled--all with moderate pain--and were randomly allocated to treatment with either diflunisal or acetaminophen with codeine. Both analgesic agents were equally effective in relieving the pain. Side effects were experienced by six patients, all of whom were receiving acetaminophen with codeine; none of the patients given diflunisal noted side effects. Global assessments of the efficacy and tolerability of the study drugs showed that 89% of 19 patients given diflunisal and 43% of 21 patients given acetaminophen with codeine considered their respective analgesics excellent or very good.

Acetaminophen↗

Temazepam as premedication in elderly patients.

One hundred and forty-five men were randomly allocated on a double-blind basis to receive either temazepam 20 mg, diazepam 10 mg or placebo as premedication. Temazepam produced more sedation than either diazepam or placebo. Postoperative recovery was assessed by a simple visuo-motor co-ordination test and was best in the placebo group. Two hours into recovery, temazepam patients could almost match their baseline performance whereas the performance of the diazepam patients was still significantly worse than pre-operatively. Temazepam is suggested as a suitable premedicant for elderly patients undergoing minor surgery.

Aged↗

Dietary fat and blood pressure: an intervention study on the effects of a low-fat diet with two levels of polyunsaturated fat.

The role of dietary fat in human blood pressure control was studied among 84 middle-aged subjects (mainly couples) in two semirural communities in North Karelia, Finland. The families were randomly allocated into two groups that, after a baseline period of 2 weeks, changed their diet for a 12-week intervention period so that the proportion of energy derived from fats was similarly reduced in both groups, from 38 to 24%, but the polyunsaturated/saturated fatty acid (P/S) ratio was increased--from 0.2 to 0.9 in group I and to 0.4 in group II. After the intervention period, both groups switched back to their usual diet for a period of 5 weeks. During the intervention period, total serum cholesterol was reduced by 16% in group I and 14% in group II. Mean body weight and urinary sodium, potassium, calcium, and magnesium excretion changes were small or nonexistent. Mean systolic blood pressure decreased 4 mm Hg in group I (P less than 0.01) and 3 mm Hg in group II (P less than 0.01), and mean diastolic blood pressure decreased 5 mm Hg (P less than 0.001) and 4 mm Hg (P less than 0.01), respectively. The reductions were reversed during the switch-back period (P less than 0.01). These results confirm previous findings of the blood-pressure-reducing effect of a low-fat/high-P/S diet. Although a number of possible confounding factors can be ruled out, the dietary constituent accounting for the blood pressure change cannot be ascertained definitely. The results showed no significant further blood pressure reduction with more than a moderately increased P/S ratio when the saturated fat intake was markedly reduced.

Adult↗

Pulsed magnetic field therapy for tibial non-union. Interim results of a double-blind trial.

Patients with tibial fractures which had remained un-united for at least 52 weeks were randomly allocated to either active or dummy pulsed magnetic field stimulators and treated in full leg plasters for 24 weeks with a non-weightbearing conservative regimen, as is usual with such techniques. Fractures in 5 of the 9 patients with working machines united and fractures in 5 of the 7 patients with dummy machines also united. These early results of this double-blind trial are compatible with a difference in success rate at 24 weeks on active treatment of + 33% to -61% (95% confidence limits) compared with the success rate on the dummy stimulators. The high proportion of fractures uniting in the control group suggests that conservative management of non-union is effective and this may explain much of the success attributed to pulsed magnetic field therapy.

Adult↗

Efficacy and tolerability of a new controlled-release formulation of metoprolol: a comparison with conventional metoprolol tablets in mild to moderate hypertension.

In a double-blind study with parallel groups 195 hypertensive patients were randomly allocated to treatment with either conventional tablets of metoprolol, 100 mg once daily, or a new controlled-release (CR) formulation of metoprolol, 100 mg once daily. The dose was doubled if the patient's diastolic blood pressure remained greater than or equal to 95 mmHg after six weeks on 100 mg, whereas well-controlled patients continued on 100 mg once daily for a further six-week period. In the metoprolol tablet group the 200 mg dose was administered in the form of Durules. There was a significant reduction from the placebo baseline in systolic and diastolic blood pressure and heart rate at 24 h after both six weeks and 12 weeks of active treatment; no significant difference in the mean reduction from baseline between the two groups was demonstrated. However, significantly more patients responded to treatment with metoprolol CR when compared with those patients taking metoprolol tablets. After six weeks of active treatment 61% of the metoprolol CR group and 56% of the conventional metoprolol tablet group had a diastolic blood pressure less than 95 mmHg. After another six weeks the corresponding figures were 83% and 69% respectively. Between week 6 and 12, 36% of patients in the metoprolol CR group and 42% of patients in the conventional metoprolol tablet group were receiving a 200 mg dose. All formulations of metoprolol were well-tolerated. Fewer subjective symptoms were reported during active treatment than during the placebo phase. There were no differences between the groups with regard to changes in laboratory variables from baseline, changes in all combined symptoms, or changes in any one symptom.

Blood Pressure↗

Controlled release salbutamol tablets versus aminophylline in the control of reversible airways obstruction.

A crossover study was carried out to compare the acceptability and efficacy of 8 mg twice daily controlled release salbutamol with 525 or 700 mg twice daily aminophylline in patients with reversible obstructive airways disease. Patients were randomly allocated into two groups to determine the treatment order. A 2-week run-in period was used to titrate the aminophylline dosage, followed by a crossover phase of two 4-week treatments. A total of 68 patients, aged 20-75 years, entered the study and 39 (57%) completed it. The two drugs differed in the pattern and severity of their side-effects. Of the 15 patients withdrawn because of severe adverse events, 12 were unable to tolerate treatment with aminophylline. There were no statistically significant differences between the treatments for lung function tests measured at the clinic, peak expiratory flow rate recorded by the patients, frequency (or severity) of asthma symptoms or the use of relief medication. Patients completing the study expressed a preference for controlled release salbutamol in 17/25 (68%) cases.

Albuterol↗

Epidemiologic methods in clinical trials.

Epidemiologic methods developed to control confounding in non-experimental studies are equally applicable for experiments. In experiments, most confounding is usually controlled by random allocation of subjects to treatment groups, but randomization does not preclude confounding except for extremely large studies, the degree of confounding expected being inversely related to the size of the treatment groups. In experiments, as in non-experimental studies, the extent of confounding for each risk indicator should be assessed, and if sufficiently large, controlled. Confounding is properly assessed by comparing the unconfounded effect estimate to the crude effect estimate; a common error is to assess confounding by statistical tests of significance. Assessment of confounding involves its control as a prerequisite. Control is most readily and cogently achieved by stratification of the data, though with many factors to control simultaneously, multivariate analysis or a combination of multivariate analysis and stratification might be necessary.

Clinical Trials as Topic↗

Percutaneous coronary intervention versus coronary bypass graft surgery for patients with medically refractory myocardial ischemia and risk factors for adverse outcomes with bypass: The VA AWESOME multicenter registry: comparison with the randomized clinical trial.

OBJECTIVES: This study was designed to compare the three-year survival after percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG) in physician-directed and patient-choice registries with the Angina With Extremely Serious Operative Mortality Evaluation (AWESOME) randomized trial results. BACKGROUND: The AWESOME multicenter randomized trial and registry compared the long-term survival after PCI and CABG for the treatment of patients with medically refractory myocardial ischemia and at least one additional risk factor for adverse outcome with CABG. The randomized trial demonstrated comparable three-year survival. METHODS: Over a five-year period (1995 to 2000), 2,431 patients with medically refractory myocardial ischemia and at least one of five risk factors (prior heart surgery, myocardial infarction within seven days, left ventricular ejection fraction <0.35, age >70 years, intra-aortic balloon required to stabilize) were identified. By physician consensus, 1,650 patients formed a physician-directed registry assigned to CABG (692), PCI (651) or further medical therapy (307), and 781 were angiographically eligible for random allocation; 454 of these patients constitute the randomized trial, and the remaining 327 constitute a patient choice registry. Survival for CABG and PCI was compared using Kaplan-Meier curves and log-rank tests. RESULTS: The CABG and PCI 36-month survival rates for randomized patients were 79% and 80%, respectively. The CABG and PCI 36-month survival rates were both 76% for the physician-directed subgroup; comparable survival rates for the patient-choice subgroup were 80% and 89%, respectively. None of the global log-rank tests for survival demonstrated significant differences. CONCLUSIONS: Both registries support the randomized trial conclusion: PCI is an alternative to CABG for some medically refractory high-risk patients.

Aged↗

Performance of West African dwarf goats fed Guinea grass-Verano stylo mixture, N-fertilized and unfertilized Guinea grass.

The supplementary values of Verano stylo in a mixed Guinea grass (Panicum maximum cv. Ntchisi)-Verano stylo (Stylosanthes hamata cv. Verano) diet from a sown grass-legume mixture and N fertilized grass were compared in West African dwarf (WAD) goats. Liveweight (LW) gain, feed intake, digestibility and N utilization were determined using 15 goats in two trials lasting for 98 days. Goats were fed Guinea grass-Verano stylo mixture (GSM), N-fertilized (NFG) and unfertilized grass (UFG). The goats were divided into three groups of five animals each and randomly allocated to the dietary treatments in a randomized complete block design. Total DM and OM intakes of the goats did not vary significantly among the forage diets and averaged 55.1 and 50.4gkg(-1)W(0.75) per day, respectively. CP intake (gkg(-1)W(0.75) per day) was highest with NFG (5.6) followed by GSM (4.8) and the UFG (3.5). Total N excreted followed the same trend as the CP intake. There was no significant difference between N-retention of GSM and NFG (28.5 and 26.7%), but goats on UFG had a negative N balance (-9.16%). Animals on GSM had significantly higher liveweight gain (31.9g per day) than those of NFG (25.1g per day) and UFG (21.9g per day) which also differed significantly. The digestibilities of total DM, OM, CP, NDF were higher with GSM than NFG or UFG. It is concluded that growing Verano stylo in mixture with Guinea grass is a better option for improving the feed quality of forage diets for goats than direct application of inorganic fertilizer at 200kgNha(-1) to the pure grass.

Journal Article↗

Combinatorial entropy and phase diagram of partially ordered ice phases.

A close analytical estimate for the combinatorial entropy of partially ordered ice phases is presented. The expression obtained is very general, as it can be used for any ice phase obeying the Bernal-Fowler rules. The only input required is a number of crystallographic parameters, and the experimentally observed proton site occupancies. For fully disordered phases such as hexagonal ice, it recovers the result deduced by Pauling, while for fully ordered ice it is found to vanish. Although the space groups determined for ice I, VI, and VII require random proton site occupancies, it is found that such random allocation of protons does not necessarily imply random orientational disorder. The theoretical estimate for the combinatorial entropy is employed together with free energy calculations in order to obtain the phase diagram of ice from 0 to 10 GPa. Overall qualitative agreement with experiment is found for the TIP4P model of water. An accurate estimate of the combinatorial entropy is found to play an important role in determining the stability of partially ordered ice phases, such as ice III and ice V.

Journal Article↗

Influence of timing on the effect of continuous extradural analgesia with bupivacaine and morphine after major abdominal surgery.

We have studied the effect of continuous extradural analgesia with bupivacaine and morphine, initiated before or after colonic surgery, in a double-blind, randomized study. Thirty-two patients were allocated randomly to receive an identical extradural block initiated 40 min before surgical incision (n = 16) or at closure of the surgical wound (n = 16). The extradural regimen consisted of a bolus of 7 ml of plain bupivacaine 7.5 mg ml-1 plus morphine 2 mg and continuous extradural infusion of a mixture of bupivacaine 7.5 mg ml-1 plus morphine 0.05 mg ml-1, 4 ml h-1 for 2 h, followed by a continuous extradural infusion of a mixture of bupivacaine 2.5 mg ml-1 plus morphine 0.05 mg ml-1, 4 ml h-1, continued for 72 h after operation. In addition, all patients received similar general anaesthesia. There was no significant difference in request for additional morphine and no significant differences between the groups in pain scores (visual analogue scale or verbal) during rest or ambulation at any time of measurement. These results do not suggest that timing of analgesia with a conventional extradural regimen is of major clinical importance in patients undergoing colonic surgery.

Aged↗

Effect of preoperative extradural bupivacaine and morphine on stump sensation in lower limb amputees.

We have examined the effect of preoperative extradural bupivacaine and morphine on postoperative stump sensation in 31 patients undergoing amputation of the lower limb in a prospective, randomized, double-blind study. Patients were allocated randomly to one of two groups: group 1 received extradural 0.25% bupivacaine 4-7 ml h-1 and morphine 0.16-0.28 ml h-1 before and during operation; group 2 received extradural saline before and during amputation and conventional analgesics for pain treatment. All patients received general anaesthesia for the amputation and extradural bupivacaine and morphine after operation. Sensory examination of the limb/stump was carried out before amputation, and after 1 week and 6 months. The following were measured: pressure pain thresholds (pressure algometry), touch and pain detection thresholds (von Frey hairs), thermal sensibility (thermal rolls), and allodynia and wind-up-like pain. There were no differences between the two groups at any of the postoperative assessments for mechanical and thermal sensibility or rate of allodynia and wind-up-like pain. Our study suggests that preoperative and intraoperative extradural block had no long-term prophylactic effect on hyperalgesia, allodynia or wind-up-like pain.

Adult↗