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Biomedical subjects

M Alexander

Publications and source records attributed to M Alexander.

At least 127 records · Page 7Linked to original sources
PubMed1993

Evaluation of fluticasone propionate (500 micrograms day-1) administered either as dry powder via a Diskhaler inhaler or pressurized inhaler and compared with beclomethasone dipropionate (1000 micrograms day-1) administered by pressurized inhaler.

Five hundred and eighty-five patients with moderate asthma, currently receiving 400-1000 micrograms day-1 of an inhaled corticosteroid, were treated for 6 weeks in a double-blind, randomized, parallel group study with either 500 micrograms day-1 fluticasone propionate as a dry powder via a Diskhaler inhaler, 500 micrograms day-1 fluticasone propionate via a pressurized inhaler or 1000 micrograms day-1 beclomethasone dipropionate via a pressurized inhaler. For all three treatment groups, mean morning and evening peak expiratory flow rates (PEFRs) increased within 1 week of the start of treatment. There were also improvements in clinic lung function, daytime and night-time asthma symptoms and a reduction in daytime and night-time rescue bronchodilator medication in all three groups. There were no statistically significant differences between the two formulations of fluticasone propionate in any of the efficacy parameters. Fluticasone propionate via the Diskhaler was significantly more effective than beclomethasone dipropionate over the 6 week study period in reducing diurnal variation (mean difference--4 l min-1, 95% CI--8 to 0 l min-1: P = 0.03). Fluticasone propionate via the Diskhaler produced a statistically significant improvement in night-time symptoms when compared to beclomethasone dipropionate whereas, beclomethasone dipropionate 1000 micrograms day-1 was statistically significantly more effective than both formulations of fluticasone propionate in improving daytime symptoms (P < 0.05). However, these statistical differences must be viewed together with the fact that very few patients recorded a score of 2 or more for both daytime or night-time symptoms. There was a similarly low incidence of adverse events with all three treatments with no evidence of hypothalamic pituitary adrenal (HPA)-axis suppression. The results of the 6-week comparative study showed that 500 micrograms day-1 fluticasone propionate whether administered via pressurized inhaler or Diskhaler is as effective and as safe as 1000 micrograms day-1 beclomethasone dipropionate administered via a pressurized inhaler in the treatment of moderate asthma. Over 12 months fluticasone propionate 500 micrograms day-1 via a pressurized inhaler was at least as effective and as well tolerated as beclomethasone dipropionate 1000 micrograms day-1.

Adolescent↗
PubMed1993

[Hemoglobin C (alpha 2 beta 2 6Glu-->lys). Study of 19 heterozygote AC carriers and of 5 cases of double hemoglobinopathy SC].

This paper describes clinical findings in subjects heterozygous for hemoglobin C and in compound heterozygotes SC. Most of our patients were coming from lands bordering the Guinea Gulf, on the inside of the loop made by the river Niger and from Haiti, which was populated by African slaves coming mainly from the Golden Coast (actually Ghana). Heterozygotes are asymptomatic and do not suffer from anemia. Age at diagnosis is higher than for SCA, although one of our cases was diagnosed at age one. Overwhelming infections or major anemia were not observed. Basal hemolysis remained moderate. HbF levels were not increased as they may be in sickle cell anemia. Splenomegaly was observed in 2/5 patients. Among severe complications we encountered, we must mention one case of foetal death, one tibial infarct, one case of pure red cell aplasia caused by parvovirus B19 infection, and one case of proliferative retinopathy.

Adult↗
PubMed1993

A multidisciplinary approach to pediatric pain: an empirical analysis.

A comprehensive assessment and multidimensional approach are critical for optimal outcomes in pediatric pain management. The purpose of this article is to describe the structure, function, and results of a multidisciplinary pain team composed of individuals from nursing, pediatric medicine, and pharmacology. The team's activities, including individual consultation on a school age/adolescent unit, are described.

Adolescent↗
PubMed1993

A placebo-controlled dose-finding study with bambuterol in elderly patients with asthma.

A new long-acting bronchodilator prodrug, bambuterol hydrochloride, was tested in a randomized, crossover, and double-blind study in elderly asthmatic patients (aged 64 to 82 years). They received placebo and 5-mg, 10-mg, and 20-mg tablets once daily for a week at each dose. The plasma concentration of the active metabolite, terbutaline, increased linearly with the dose of drug (p < 0.001). Peak expiratory flow rate increased with dose in the morning (p < 0.001 for 10-mg and 20-mg doses) and afternoon (p < 0.05 for 10 mg; p < 0.001 for 20 mg) and was different from placebo for the 10-mg/d and 20-mg/d regimens. The use of supplemental inhaled beta 2-adrenergic agonist therapy was reduced during the night for the 10-mg (p < 0.05) and 20-mg (p < 0.01) doses in comparison to placebo. No significant effects of treatment on blood pressure and pulse were demonstrated. Tremor and palpitations were mild and related to the dose. These data suggest that treatment once daily with bambuterol hydrochloride in a dose of 10 or 20 mg improves pulmonary function and is well tolerated as bronchodilator therapy in elderly patients with asthma.

Aged↗
PubMed1993

Measurement of oxygen consumption after uncomplicated acute myocardial infarction.

BACKGROUND: Oxygen consumption (VO2) has been shown to be decreased after acute myocardial infarction (AMI) complicated by cardiogenic shock. STUDY OBJECTIVE: To evaluate early measurement of VO2 by indirect calorimetry after an uncomplicated AMI (UAMI). STUDY DESIGN: Prospective nonrandomized case study. SETTING: Emergency department of a large urban hospital. PARTICIPANTS AND INTERVENTIONS: Twenty-six consecutive patients presenting with confirmed UAMI. VO2 was measured by indirect calorimetry (Deletrac, Datex Ins,) which is noninvasive. All patients received buccal or intravenous nitroglycerin and thrombolytic therapy, and none received opiates before VO2 measurement. RESULTS: Two groups of patients were identified by subsequent development of cardiogenic shock. Group 1 did not develop cardiogenic shock, and group 2 developed shock within 24 h of admission. Group 1 (n = 22) had a significantly higher VO2 compared to group 2 (n = 4), mean 154(SD 25) vs mean 100(SD 13) ml/min.m2, p < 0.002. Group 1 had a significantly higher increase in basal metabolic rate than group 2, mean 30 percent (SD 11) vs mean 10(SD 15) percent, p < 0.007. There was no significant difference in age, heart rate (HR), shock index (SI), or rate-pressure product (RPP) between groups 1 and 2. All patients in group 2 developed cardiogenic shock despite thrombolytic therapy, and two died within 24 h of admission. CONCLUSION: VO2 is increased in UAMI and represents increased metabolic demands of peripheral tissues and not cardiac oxygen uptake. A reduction in VO2 (< 100 ml/min.m2) after AMI may be an early predictor of subsequent development of cardiogenic shock. Measurement of VO2 in UAMI by indirect calorimetry in the emergency department may be of value to identify patients at high risk and could influence their management.

Aged↗
PubMed1993

Visual evoked potential changes in patients with tropical pancreatic diabetes.

Visual impairment is an important complication of diabetes. There are conflicting reports on Visual Evoked Potential (VEP) changes in diabetes. P100 latency of VEP was evaluated in twenty patients with Tropical Pancreatic Diabetes (TPD) and compared with that of age and sex matched controls. There was no statistically significant difference in the P100 latency between the two groups. There was no correlation between the P100 latency and the severity of diabetes or presence of defective vision or retinopathy. The defective vision in diabetes is likely to be due to ocular causes rather than due to a defect in the central visual pathways.

Adult↗
PubMed1993

Characteristics of epidemic hepatitis A in Baltimore City: implications for control measures.

In 1988, a hepatitis A epidemic began in Baltimore, Maryland. A total of 607 cases were reported to the Baltimore City Health Department between the period November 1, 1988, and December 31, 1989. The health department conducted case investigations to identify factors important to the development of control measures. Immunoglobulin was given to appropriate contacts, and an educational campaign was initiated. Of the 607 reported cases, 63% were white and 57% were male. Cases were geographically clustered within 5 of Baltimore's 23 zip codes. Among the 242 adults interviewed, 43% self-reported drug use and 44% were unemployed. Twenty-one percent of the adults and 56% of the children reported contact with either a suspected or confirmed case of hepatitis. Despite control efforts, the epidemic continued through 1990. Barriers to implementing traditional control measures resulted in continuing transmission of hepatitis A in the community.

Adolescent↗
PubMed1993

[Transient aplasia of the red progenitor cells manifest in a child with double heterozygote Hb SC carriership: the role of human parvovirus B19 (HPV-B19)].

Severe pure red cell anaemia due to B19 parvovirus infection is reported in a child with haemoglobin SC disease. B19 parvovirus infection was demonstrated by specific IgM. Although hypoplastic crisis occurring in SC children is usually less frequent and more benign than in sickle- cell anaemia, it necessitated several blood transfusions in our patient. The child recovered rapidly and was discharged after 12 days. This case again illustrates the role of HPV-B19 in the development of transient red cell aplasia occurring in patients with haemolytic anaemia. However, it is unusual since in the few reported children with HbSC disease and HPV-B19 infection, aregenerative anaemia remained moderate and did not generally require blood transfusions.

Anemia, Aplastic↗
PubMed1992

Epidemiology of the post-polio syndrome.

A late-onset syndrome, consisting of muscle weakness, muscle pain, and unaccustomed fatigue, has been reported with increasing frequency among former poliomyelitis patients. A population-based cohort of poliomyelitis patients from Allegheny County, Pennsylvania, was traced and surveyed to estimate the prevalence and incidence and to identify determinants of the post-polio syndrome. A questionnaire validated in clinical examinations of 40 cohort members was used in the survey. The prevalence of the post-polio syndrome was 28.5% of all paralytic cases (95% confidence interval 24.4-32.6). The risk of post-polio syndrome was significantly higher among patients who sustained substantial permanent impairment after polio and among females. The incidence did not vary with age at acute onset, acute severity, or level of physical activity after recovery. The strongest determinant of post-polio syndrome onset was the length of the interval following the acute illness, with incidence peaking at 30-34 years. Of all cases of post-polio syndrome, 79% reported no major change in impairment status since onset. This study demonstrates that poliomyelitis patients are not equally susceptible to post-polio syndrome within the interval of 30-40 years after the original illness. For syndrome cases, the onset was associated with new neuromuscular symptoms and functional changes but not with major new impairment.

Acute Disease↗
PubMed1992

Effect of chymotrypsin on human cholecystokinin release: use of clostripain in the validation of a new radioimmunoassay.

We have developed and validated a new radioimmunoassay for cholecystokinin. In order to establish that the antiserum binds large and small forms of CCK to an equal extent, we used the microbial enzyme clostripain, which cleaves large forms of CCK yielding CCK 8. Cleavage by clostripain of synthetic and purified forms of CCK, and CCK extracted at from human jejunum and CCK in human plasma was found not to affect immunoactivity, indicating that the antiserum reacts similarly with all forms of CCK. There is controversy over whether intraduodenal trypsin inhibits release of CCK in man. We used our radioimmunoassay to investigate whether chymotrypsin, rather than trypsin, could be the major mediator of negative feedback control of CCK release. Six normal subjects received an intraduodenal infusion of L-phenylalanine and L-tryptophan on two occasions, with the addition of either 1 g/l bovine chymotrypsin or 1 g/l albumin. Plasma CCK concentrations rose in response to the amino acid infusion, but were not affected by the addition of chymotrypsin, indicating that this enzyme is not a mediator of CCK feedback regulation in man.

Antibody Specificity↗
PubMed1992

Hospital records as a data source for occupational disease surveillance: a feasibility study.

To assess the feasibility of using hospital records for occupational disease surveillance and to evaluate the quality of the industry/occupation (I/O) information available in these records, the computer file of all discharge diagnoses from a large health maintenance organization during 1985 was reviewed. The frequencies of discharge diagnoses previously listed as Sentinel Health Events (Occupational), or SHE (O), were calculated and three possible SHE(O) diagnoses--lung cancer, bladder cancer, and toxic hepatitis--were selected for further review. Outpatient charts of patients discharged for each diagnosis were abstracted with regard to I/O information and the discharged patients were interviewed by telephone to obtain a lifetime occupational history. The accuracy of the I/O information obtained from the hospital chart was compared to that obtained by patient interview by number of digits matched on standard classification codes. The frequencies of matches for occupation and industry were greater for "usual" than for "last" categories with both cancer diagnoses, but were similar for "usual" and "last" categories with toxic hepatitis. To assess the proportion of each possible SHE(O) diagnosis that was related to workplace exposures, the I/O information obtained by interview was rated in a blinded fashion by an experienced occupational medicine physician. The highest probability ratings for work-relatedness were noted for lung cancer, primarily due to asbestos exposure. The results of this study suggest that hospital records can be used to identify possible SHE(O); if adequate I/O information is available, then work-relatedness can be assessed. However, the accuracy of I/O obtained from hospital charts is relatively low. The efficient and accurate collection of I/O information from hospital records will require the use of a simple, easily coded instrument to be routinely administered on admission.

Asbestos↗
PubMed1992

Malaria therapy in 452 patients, with special reference to the use of quinine.

We investigated the efficacy and toxic potential of antimalarial therapy regimens in 452 malaria patients treated between 1980 and 1990. Drug regimens in 330 non-immune travellers were compared with those of 122 semi-immunes with acute malaria; 71% patients acquired their infection in tropical Africa, and the 288 Plasmodium falciparum infections were the most prevalent species. Because of increasing drug resistance or toxicity of chloroquine, pyrimethamine-sulfadoxine and even mefloquine, quinine proved to be the most effective antimalarial against P. falciparum and the only one which did not lead to recrudescences. These occurred in 10% patients after chloroquine and 6% after mefloquine. Cinchonism occurred in 25% of those treated with quinine, but it was fully reversible and never necessitated withdrawal of the drug. We conclude that quinine is highly effective in the treatment of P. falciparum infection and is mandatory if the clinical condition requires a fast-acting blood schizonticide, in cases of hyper-parasitaemia and if multi-drug resistance occurs; its use should not be restricted by reversible side-effects such as cinchonism.

Adolescent↗
PubMed1992

Benzodiazepines for acute pain in children.

When pediatric pain is refractory and unresponsive to appropriate use of analgesic agents, there might be additional physical or psychologic dimensions of the pain that are not addressed by the analgesics. In addition to appropriate analgesic therapy, the psychologic needs of the child should be directly addressed and appropriate adjunctive physical modalities employed. Although benzodiazepines lack direct analgesic effects, they can reduce the distress associated with acute pain states by decreasing anxiety, insomnia, and muscle spasms that can be associated with acute pain. Intermediate or long-acting benzodiazepines in modest doses can be useful adjunctive agents when used short term for the treatment of selected acute pain complaints. In the highly distressed school-age child or adolescent with pain complaints relatively unresponsive to appropriate care, judicious use of benzodiazepines is worthy of consideration.

Acute Disease↗
PubMed1992

Bringing parents into school clinics: parent attitudes toward school clinics and contraception.

Prior to implementing a change in school clinic policy to allow dispensing of contraceptives, parents of school-based clinic (SBC) enrollees were surveyed regarding attitudes toward clinic quality of care, desired services, and contraceptive distribution. Telephone interviews were conducted with a systematic sample of 262 parents who normally are in charge of the adolescent's health care. Parental opinion was felt to be crucial in shaping Baltimore SBC contraception policy. Parents overwhelmingly endorsed current clinic services including family planning for sexually active teens, annual physicals, and drug and alcohol counseling. Most parents rated the SBC as excellent (25%) or very good (36%), although a substantial minority found it difficult to rate the clinics (27%, "don't know"). Parents with prior verbal contact (45%) were more likely to rate the clinic as excellent (35% versus 16%) and less likely to respond "don't know" (13% versus 38%, p less than 0.001). Parent attitudes toward contraception was context specific: 63% endorsed and 27-30% opposed prescribing and dispensing. If a boy (or girl) was already having sex, 76% (or 75%) of parents supported and 14% (or 17%) opposed providing birth control pills or condoms. With parental permission, 93% supported contraception and only 3% were opposed. No differences were found by age, race, gender, or grade of student. Prior verbal communication with the clinic did not affect parent attitudes toward contraception. Consideration of parent attitudes was critical to changing SBC contraceptive dispensing policy in Baltimore. Contraceptive distribution, after counseling and necessary medical care, was initiated in September 1990. The parent and community response has been very supportive.

Adolescent↗
PubMed1992

Sleep and cardiorespiratory characteristics of infant victims of sudden death: a prospective case-control study.

We studied the polygraphic sleep recordings of 30 infants who eventually died of sudden infant death syndrome (SIDS) and those of 60 matched control infants. All records were extracted from 20,750 sleep studies collected prospectively in 10 sleep laboratories. Of the 30 future SIDS victims, 5 were siblings of SIDS victims and 9 were studied after an apparent life-threatening event. For each SIDS victim, two normal control infants were matched for sex, gestational age, postnatal age and weight at birth. The future SIDS infants were reported to have more frequent episodes of regurgitations after feeding (p = 0.01) and profuse sweating during sleep (p = 0.01) than the control subjects. Only two polysomnographic variables characterized the future SIDS infants. Compared to control subjects, the SIDS infants moved less during sleep (p = 0.04) and had significantly more frequent obstructed breathing events. Obstructive and mixed apneas were seen in 23 of 30 future SIDS victims, but in only 9 of 60 control subjects (p = 0.01). The obstructed and mixed apneas lasted longer in the SIDS than in the control infants (p = 0.01) but did not exceed 15 seconds. The obstructed breaths occurred mainly in rapid eye movement sleep (78% of the events) and were accompanied by drops in heart rates to 68 beats per minute and in SaO2 levels to 75%. The present report adds further indirect evidence for a possible sleep-related impairment of respiratory control in some infants who eventually died of SIDS.

Case-Control Studies↗
PubMed1992

Normal uptake in a gravid uterus on Tc-99m DTPA imaging.

A 17-year-old female kidney transplant patient was admitted to the hospital with a fever and right lower quadrant pain. Although she was 14 weeks' pregnant, renal DTPA imaging was performed because graft rejection was suspected. The study revealed fetal uptake of DTPA medial to the transplanted kidney. This has not been previously reported. Uptake in a normal uterus has been described using Tc-99m pertechnetate, Tc-99m glucoheptonate, and Tc-99m MDP. It is essential to recognize uptake in the gravid uterus and to differentiate it from uptake secondary to a pathologic entity.

Adolescent↗
PubMed1992

Influence of Calcium, Iron, and pH on Phosphate Availability for Microbial Mineralization of Organic Chemicals.

A study was conducted to determine some of the factors affecting the P requirement for the biodegradation of p-nitrophenol, phenol, and glucose by Pseudomonas and Corynebacterium strains. Mineralization of glucose was rapid and the Pseudomonas sp. grew extensively in solutions with 5 and 10 mM phosphate, but the rate and extent of degradation were low and the bacterial population never became abundant in media with 0.2 mM phosphate. Similar results were obtained with the Corynebacterium sp. growing in media containing p-nitrophenol or phenol and in solutions with a purified phosphate salt. The extent of growth of the Corynebacterium sp. was reduced with 2 or 10 mM phosphate in media containing high Fe concentrations. Ca at 5 mM but not 0.5 mM inhibited p-nitrophenol mineralization by the Corynebacterium sp. with phosphate concentrations from 0.2 to 5.0 mM. Phenol mineralization by the Pseudomonas sp. in medium with 0.2 mM phosphate was rapid at pH 5.2, but the bacteria had little or no activity at pH 8.0. In contrast, the activity was greater at pH 8.0 than at pH 5.2 when the culture contained 10 mM phosphate. These effects of pH were similar in media with 5 mM Ca or no added Ca. We conclude that the effect of P on bacterial degradation can be influenced by the pH and the concentrations of Fe and Ca.

Journal Article↗