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Biomedical subjects

M Welch

Publications and source records attributed to M Welch.

At least 109 records · Page 6Linked to original sources
PubMed1991

Once daily triamcinolone acetonide nasal spray is effective for the treatment of perennial allergic rhinitis.

A randomized, double-blind, placebo-controlled, parallel group study was conducted in 11 centers to evaluate the safety and efficacy of a once-a-day regimen of 110 micrograms, 220 micrograms; and 440 micrograms of triamcinolone acetonide intranasal aerosol versus placebo in relieving the symptoms of rhinitis in 305 adult and older pediatric patients with perennial allergic rhinitis. Nasal stuffiness, nasal discharge, sneezing, nasal itching and the nasal index (the sum of the mean scores of the first three symptoms) averaged over the first 6 weeks and second 6 weeks of the study were significantly reduced in patients who received the 220 micrograms/day and the 440 micrograms/day dosages. The 110 micrograms/day group had a reduction in these nasal symptoms, but only the sneezing and nasal index were significantly (P less than .05) better than placebo. During the last 6 weeks of the study, patients were allowed to take oral back-up medication for their nasal symptoms; all three groups receiving triamcinolone nasal aerosol took less back-up medication than did the placebo group. There were no significant adverse effects or laboratory abnormalities noted during this study. Intranasal triamcinolone acetonide 220 micrograms and 440 micrograms, used once-a-day for 12 weeks is clinically and statistically superior to placebo for the treatment of perennial allergic rhinitis.

Administration, Intranasal↗
PubMed1990

Pausing, switching and speed fluctuation of the bacterial flagellar motor and their relation to motility and chemotaxis.

Wild-type Escherichia coli and Salmonella typhimurium cells, tethered to glass by their flagella, rotate with brief intermittent pauses, the prevalence of which is decreased by attractants and increased by repellents. By attaching latex beads to filaments of a S. typhimurium mutant having straight rather than helical flagella, it was established that the flagella on free cells also pause intermittently. Pausing is therefore an intrinsic feature of the motor and not an artifact associated with tethering. In tethered cells of wild-type strains and non-chemotactic mutants defective in transducers, chemotaxis proteins, or the flagellar switch, both the classical response to chemotactic stimuli (change in direction of rotation from counterclockwise to clockwise or vice versa), and the pausing response to such stimuli, were linked together. No separate signal for pausing was found. In comparing different strains under different stimulation conditions, it was found that cells that never reversed seldom if ever paused, while cells that reversed frequently paused frequently. It is suggested that pausing is the result of futile switching events. A modified description of tumbling and chemotaxis is provided in which pausing, as well as reversal, has a role. Suppression of reversals and pauses by attractant stimuli commonly resulted in an increase in the speed of counterclockwise rotation; this may be because of suppression of pauses or reversals that are too brief to be detected. The clockwise rotation rate of unstimulated cells, which commonly was faster than their counterclockwise rate, was not further increased by repellent stimuli. The rotation rate of any given cell under any given condition was found to fluctuate on all time-scales measured. The study also revealed that some of the common repellents of E. coli and S. typhimurium slow down or stop the motor; these effects are not mediated by the chemotaxis machinery or intracellular pH.

Cell-Free System↗
PubMed1990

Microdochectomy for discharge from a single lactiferous duct.

Microdochectomy for persistent discharge from a single lactiferous duct was performed in 162 women. Invasive or in situ ductal carcinoma was diagnosed in 16 patients (10 per cent), none of whom had a palpable lump. The discharge was blood-stained in 14 of these women and in two it was clear. Mammography was performed in 15 of these 16 patients and was abnormal in only five. Three patients had atypical ductal hyperplasia, one of whom subsequently developed an invasive ductal carcinoma. Microdochectomy for persistent discharge from a single lactiferous duct is curative and gives a diagnosis of the cause. It remains the treatment of choice whether the discharge is blood-stained or clear.

Adolescent↗
PubMed1990

Comparison of brachial and radial arterial pressure monitoring in patients undergoing coronary artery bypass surgery.

The pressure in either the radial (n = 88) or proximal brachial artery (n = 82) was compared with aortic pressure before and after cardiopulmonary bypass (CPB) in patients receiving coronary artery bypass grafts. Radial artery pressures were measured via 20-G 5-cm long catheters, brachial artery pressures via 20-G 12.7-cm catheters, and aortic pressures were measured via a luer port in the aortic perfusion cannula. Transducers were connected via 122-cm long tubing. For the various systems, mean natural frequencies were 16.1 to 17.7 Hz and damping coefficients were 0.16 to 0.27. Before CPB the brachial systolic, diastolic, and mean pressures were 108.2 +/- 5.2%, 100.9 +/- 2.8%, and 99.6 +/- 2.3% of aortic; respective radial pressures were 113.9 +/- 9.6%, 99.5 +/- 2.8%, and 98.4 +/- 2.8% of aortic. Immediately after CPB the brachial pressures were 99.5 +/- 7.5%, 98.9 +/- 3.5%, and 97.4 +/- 2.9% of aortic, whereas respective radial pressures were 92.1 +/- 14.6%, 94.7 +/- 5.6%, and 90.8 +/- 7.4%. All brachial and radial as a per cent of aortic pressure medians were significantly different, and except for prebypass diastolic and mean, the variance for brachial pressures was significantly less than that for pressures in the radial artery. The prebypass brachial correlation (r) with aortic for systolic, diastolic, and mean were 0.90, 0.98, and 0.98; respective radial correlations with aortic were 0.78, 0.97, and 0.95. Postbypass brachial systolic, diastolic, and mean correlations were 0.91, 0.97, and 0.98; radial were 0.50, 0.93, and 0.83. Brachial artery pressures were more accurate and reliable than radial artery pressures.

Aged↗
PubMed1990

Metabolic and cardiorespiratory parameters during three consecutive days of exhaustive running.

The purpose of this study was to examine serum metabolites, cardiorespiratory parameters and creatine kinase during running on 3 consecutive days. Thirteen trained marathon runners exercised to exhaustion on a treadmill at 85 +/- 3% VO2max on each day. Expired gases and blood samples were obtained at rest, after 10 and 30 min of exercise and at exhaustion. There were no significant differences over days for glucose, insulin, lactate, free fatty acids, creatine kinase, oxygen uptake, minute ventilation, heart rate, rating of perceived exertion, respiratory exchange ratio or run times. Serum glycerol was elevated (p less than 0.05) both at rest and during exercise on each successive day. The findings suggested that, except for serum glycerol, acute metabolic and cardiorespiratory responses to exhaustive aerobic exercise are not altered by 3 days daily repetition by endurance trained individuals.

Cardiovascular System↗
PubMed1990

Multicenter evaluation of triamcinolone acetonide nasal aerosol in the treatment of adult patients with seasonal allergic rhinitis.

Triamcinolone acetonide aerosol inhalation therapy is effective for the prophylactic treatment of asthma. Recently, the delivery system for this preparation has been modified for use in allergic rhinitis. A total of 180 adult patients with symptomatic seasonal allergic rhinitis participated in this double-blind, placebo-controlled, multicenter trial. Patients received either placebo or approximately 25 mg per actuation of triamcinolone acetonide aerosol per nostril, qid, for 4 weeks. Each patient kept a daily diary rating rhinitis symptoms. Both the patient and the physician also gave global evaluations of drug efficacy. Of 168 evaluable patients, significant reductions were seen at week 1, week 2, and in the overall study evaluation of ratings for intensity (P less than .001) and duration (P less than .05) of various rhinitis symptoms such as nasal stuffiness, discharge, and sneezing in the group given triamcinolone acetonide. Superiority to placebo group was evident as early as day 1 and maintained throughout the study. Both patients and physicians rated triamcinolone acetonide as significantly more effective than placebo for the duration of the study (P less than .001). There was a marked reduction in nasal smear eosinophils in the triamcinolone acetonide group. There was no difference between groups in safety evaluations including no evidence of suppression of the adrenal axis and no evidence of fungal infection. This study demonstrates that triamcinolone acetonide in a dose of 25 micrograms per nostril, qid, is effective, well tolerated, and safe in reducing symptoms in adult patients with seasonal allergic rhinitis.

Administration, Intranasal↗
PubMed1989

Anesthetic management for surgical removal of renal carcinoma with caval or atrial tumor thrombus using deep hypothermic circulatory arrest.

Twenty cases of renal carcinoma with tumor thrombus extending into the vena cava or atrium, in which cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA) were used, are reviewed. Arterial, central venous (n = 9), or pulmonary artery catheters (n = 11), ECG, and rectal or bladder and pharyngeal temperatures were used for monitoring. The anesthetic was a high-dose narcotic supplemented with a nondepolarizing relaxant and a volatile agent. The surgery consisted of mobilization of the kidney followed by CPB via atrial and aortic cannulae, cooling via CPB, exsanguination, and removal of thrombus during DHCA. Duration of cooling was 21 +/- 7 minutes to a pharyngeal temperature of 15.8 degrees +/- 2.6 degrees C with alpha-stat pH management; DHCA lasted 26 +/- 10 minutes, and rewarming was continued to a mean pelvic temperature of 36.2 degrees C. Duration of surgery was 8.1 +/- 1.6 hours. The mean initial hematocrit was 33.5%, mean lowest Hct during CPB was 16.9%, and mean Hct at the end of surgery was 30%. Intraoperatively, 9.0 +/- 6.4 units of blood were used, and most patients received component therapy. Average crystalloid use was 7 L, and albumin or hetastarch (1.3 +/- 0.9 L) was used in 13 patients. One patient with severe cardiac disease could not be weaned from CPB. In the 19 operative survivors, there were no neurological deficits. There was one late death from pulmonary complications. The use of thiopental (n = 13), dexamethasone (n = 11), or mannitol (n = 19) was not clearly related to outcome. Hypothermia, hemodilution, alpha-stat pH management, and normoglycemia are believed to be important aspects of perioperative care.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

A cultural perspective and the second wave of educational reform.

A prerequisite call for understanding the culture of the school as well as the processes of change that are associated with the innovations brought by the new wave of educational reform is presented in this article. The school as a culture, variables of receptivity to change within the school culture, and the change process and its implications are examined.

Culture↗
PubMed1988

Pausing of flagellar rotation is a component of bacterial motility and chemotaxis.

When bacterial cells are tethered to glass by their flagella, many of them spin. On the basis of experiments with tethered cells it has generally been thought that the motor which drives the flagellum is a two-state device, existing in either a counterclockwise or a clockwise state. Here we show that a third state of the motor is that of pausing, the duration and frequency of which are affected by chemotactic stimuli. We have recorded on video tape the rotation of tethered Escherichia coli and Salmonella typhimurium cells and analyzed the recordings frame by frame and in slow motion. Most wild-type cells paused intermittently. The addition of repellents caused an increase in the frequency and duration of the pauses. The addition of attractants sharply reduced the number of pauses. A chemotaxis mutant which lacks a large part of the chemotaxis machinery owing to a deletion of the genes from cheA to cheZ did not pause at all and did not respond to repellents by pausing. A tumbly mutant of S. typhimurium responded to repellents by smooth swimming and to attractants by tumbling. When tethered, these cells exhibited a normal rotational response but an inverse pausing response to chemotactic stimuli: the frequency of pauses decreased in response to repellents and increased in response to attractants. It is suggested that (i) pausing is an integral part of bacterial motility and chemotaxis, (ii) pausing is independent of the direction of flagellar rotation, and (iii) pausing may be one of the causes of tumbling.

Cell Movement↗
PubMed1985

A study of a Self-Care Rehabilitation Program in pediatric asthma.

The Self-Care Rehabilitation in Pediatric Asthma (SCRPA) project was designed to ascertain the level to which children with asthma are able to acquire the asthma knowledge and skills presented in a self-management training program conducted by the American Lung Association of Utah and the effect of such training on the asthma experience. The preschool SCRPA Curriculum (ages 2-5) consisted of six 1-hour classes scheduled twice a week for 3 weeks. The first and last classes were for one or both parents only, and the middle four sessions were for the child and parent(s). The school-age SCRPA curriculum (ages 6-14) consisted of eight 90-minute classes for both child and parent(s) scheduled twice a week for 4 weeks. Private physicians referred 21 preschool children and 38 school-age children into the program. The school-age children were randomly assigned to a study or control group, and the preschool children served as their own controls. A comparison of asthma episodes during the 3 months before and after training showed a statistically significant decrease in the number of episodes but no change in severity in the preschool, school study, and school control groups. The decrease in episodes for the control groups suggest that the family record keeping required of all subjects may have a beneficial effect, a phenomenon worth further investigation. Also, the school-age group, in pre- and posttesting, demonstrated that the SCRPA curriculum increased knowledge and skills in the study group, changes not found in the control group.

Asthma↗