Biomedical subjects

M L Andrews

Publications and source records attributed to M L Andrews.

At least 19 recordsLinked to original sources

PubMed2000

Clinical and genetic variables associated with acute arousal and nonarousal-related cardiac events among subjects with long QT syndrome.

In patients with the long QT syndrome (LQTS), the occurrence of cardiac events (syncope or cardiac arrest) is frequently associated with acute arousal caused by exercise, swimming, emotion, or noise. However, cardiac events may also occur during sleep or with ordinary daily activities. The purpose of this study was to determine whether there are differential clinical, electrocardiographic, and genetic features among LQTS patients who experienced cardiac events with and without acute arousal. We identified 1,325 patients with cardiac events from the International LQTS Registry. Based on the precipitating conditions of the first event, 427 patients were classified as arousal, 345 as nonarousal, and the remaining 553 were unknown (not classifiable). Gene linkage was known in 78 of the 772 patients with classifiable first events. The age at first cardiac event was significantly younger in the arousal than the nonarousal group (11.7 vs. 15.5 years, respectively; p<0.001). The arousal-type patients had a higher rate of subsequent cardiac events during follow-up after the index event than the nonarousal-type patients (p = 0.02). Arousal-related cardiac events occurred in 85% of LQT1, 67% of LQT2, and 33% of LQT3 patients (p = 0.008). This study provides evidence that the genotype is an important determinant of the LQTS phenotype in terms of arousal and nonarousal-related cardiac events.

Acute Disease↗

PubMed2000

Effectiveness and limitations of beta-blocker therapy in congenital long-QT syndrome.

BACKGROUND: beta-blockers are routinely prescribed in congenital long-QT syndrome (LQTS), but the effectiveness and limitations of beta-blockers in this disorder have not been evaluated. METHODS AND RESULTS: The study population comprised 869 LQTS patients treated with beta-blockers. Effectiveness of beta-blockers was analyzed during matched periods before and after starting beta-blocker therapy, and by survivorship methods to determine factors associated with cardiac events while on prescribed beta-blockers. After initiation of beta-blockers, there was a significant (P<0.001) reduction in the rate of cardiac events in probands (0.97+/-1.42 to 0.31+/-0.86 events per year) and in affected family members (0. 26+/-0.84 to 0.15+/-0.69 events per year) during 5-year matched periods. On-therapy survivorship analyses revealed that patients with cardiac symptoms before beta-blockers (n=598) had a hazard ratio of 5.8 (95% CI, 3.7 to 9.1) for recurrent cardiac events (syncope, aborted cardiac arrest, or death) during beta-blocker therapy compared with asymptomatic patients; 32% of these symptomatic patients will have another cardiac event within 5 years while on prescribed beta-blockers. Patients with a history of aborted cardiac arrest before starting beta-blockers (n=113) had a hazard ratio of 12.9 (95% CI, 4.7 to 35.5) for aborted cardiac arrest or death while on prescribed beta-blockers compared with asymptomatic patients; 14% of these patients will have another arrest (aborted or fatal) within 5 years on beta-blockers. CONCLUSIONS: beta-blockers are associated with a significant reduction in cardiac events in LQTS patients. However, syncope, aborted cardiac arrest, and LQTS-related death continue to occur while patients are on prescribed beta-blockers, particularly in those who were symptomatic before starting this therapy.

Adolescent↗

PubMed1999

Asthma and the risk of cardiac events in the Long QT syndrome. Long QT Syndrome Investigative Group.

While acquiring data for the International Long QT Syndrome Registry, we noticed that a number of patients referred for long QT syndrome (LQTS) were affected by asthma. The effect of asthma comorbidity on clinical course of LQTS has not been studied. This study aimed to evaluate the prevalence of asthma in patients with LQTS, determine the influence of asthma comorbidity on outcome of LQTS patients, and to investigate the confounding effects of beta mimetics and beta blockers on the occurrence of cardiac events in asthmatic patients. The influence of asthma on risk of cardiac events (syncope, aborted cardiac arrest, or LQTS death) was evaluated after accounting for age, gender, QTc, and RR interval duration, beta-blocker and beta-mimetic use. Asthma was identified in 226 (5.2%) of 4,310 studied LQTS family members. Longer QTc duration was associated with higher incidence of asthma (p <0.001). Asthma was independently associated with significantly increased risk of cardiac events in affected LQTS patients (hazard ratio 1.32; p = 0.048) and in borderline-affected family members (hazard ratio 2.08; p = 0.004) after adjustment for QTc, RR interval, and gender. An increased risk of cardiac events in asthmatic patients observed before beta-blocker therapy was reduced after initiation of treatment with beta blockers. In conclusion, the occurrence of asthma in LQTS patients increases with QTc duration. Asthma comorbidity in LQTS patients is associated with an increased risk of cardiac events. The asthma-associated increase in the risk of LQTS-related cardiac events is diminished after initiation of beta-blocker therapy, suggesting a possible role of beta-receptor modulation underlying asthma-LQTS association.

Adrenergic beta-Agonists↗

PubMed1999

Comparison of clinical and genetic variables of cardiac events associated with loud noise versus swimming among subjects with the long QT syndrome.

Acute auditory stimuli and swimming activities are frequently associated with syncope, aborted cardiac arrest, and death in the long QT syndrome (LQTS). We investigated the clinical and genetic findings associated with cardiac events precipitated by these arousal factors. The study population involved 195 patients with an index cardiac event associated with a loud noise (n = 77) or swimming activity (n = 118). Patients with events associated with loud auditory stimuli were older at their index event and were more likely to be women than patients who experienced events during swimming-related activities. Patients with an index event associated with loud noise were likely to have subsequent events related to auditory stimuli; patients with an index event associated with swimming were likely to have recurrent events related to swimming or physical activities. Family patterning of auditory and swimming and/or physical activity-related events was evident. Genotype analyses in 25 patients revealed a significant difference in the distribution of index cardiac events by genotype (p <0.001), with all 19 patients with swimming-related episodes associated with LQT1 genotype and 5 of 6 patients with auditory-related events associated with LQT2 genotype. The clinical profile and genotype findings of patients with LQTS who experience cardiac events related to acute auditory stimuli are quite different from those who experience events accompanying swimming activities.

Acoustic Stimulation↗

PubMed1999

Reliability of student evaluations of voice therapy implications for theory and training.

This study examines reliability and the focus of attention of evaluations of voice therapy sessions. Therapy sessions were provided by 8 clinician-client pairs. For each pair, two 20-minute therapy sessions were evaluated by 50 undergraduate student raters and by 3 experienced clinicians. The goal of all therapy sessions was the modification of the frequency and type of voice onset. Raters evaluated each session using 12 behavioral and interpersonal criteria. Results indicated that (1) interrater reliability coefficients for each of the 12 criteria were moderately high to high, (2) the highest coefficients were found for ratings of the client, and (3) ratings of the client were found to be the most consistent across 2 sessions. Intrarater reliability was highest in ratings of quality, use of counseling, clarity and use of feedback, and amount of explanation by the clinician.

Adult↗

PubMed1998

An acoustical and perceptual analysis of the vocal behavior of classroom teachers.

This study examined perceptual evaluations of classroom teachers, acoustic measures of their voices ( fundamental frequency [F0], frequency range [F0SD], % jitter, and % shimmer), and behavioral measures (rate, dysfluencies, and episodes of vocal fry). This preliminary study attempted to identify perceptual and acoustic measures that discriminate between effective and less effective classroom teachers. Seven teachers were recorded on audiotape while presenting a 10-12 minute lecture. Voice samples (N > 200) for each teacher were subjected to acoustic analysis. Audiotapes were evaluated by listeners (N = 180), who scale-rated and used an adjective checklist to determine teachers' overall effectiveness. A three-member team evaluated global aspects of voice (e.g., use of pauses, inflections, contours, and phrasing). Results indicated that frequency range, frequency variability, rate, and number of dysfluencies appeared to correlate with perceptual judgments of teaching effectiveness and specific adjective descriptors. F0, % jitter, and % shimmer did not appear to be linked to perceptual judgments. Individual case profiles were established and recommendations were made for future empirical research involving larger samples of teachers.

Adult↗

PubMed1997

Gender presentation: perceptual and acoustical analyses of voice.

This study investigated the perceptual and acoustical characteristics of vocal presentation in both the masculine and the feminine modes by the same group of male subjects. Listeners (N = 88) evaluated 22 voice samples by using 18 semantic differential scales and 57 adjectives. The 22 voice samples were provided by 11 biologically male speakers, who described themselves as heterosexual crossdressers. Each speaker read a standard passage under controlled conditions. In one reading, they demonstrated their typical masculine voice and in the other they spoke in their feminine voice. Acoustical analyses included mean fundamental frequency, frequency range, overall passage duration, and duration of a sample of stressed vowels. Results indicated that listeners heard significant differences between masculine and feminine presentations across the 11 speakers and the 18 semantic differential scales. Masculine-feminine and high-low pitch were the most salient scales in the perceptual judgments. Acoustical analyses indicated wide variation according to speaker and condition. Clinical applications are provided.

Adult↗

PubMed1997

The singing/acting child: a speech-language pathologist's perspective.

Performance-oriented children who encounter voice problems benefit from a team approach to intervention. Developmental and psychosocial issues in addition to the acquisition of information and vocal skills must be addressed. This article presents information from a speech-language pathologist's perspective and includes some examples of clinical approaches and strategies. The importance of building motivation to change vocal habits and the need for the child to develop insight and self-evaluation strategies is emphasized.

Child↗

PubMed1997

Cutaneous manifestations of chronic graft-versus-host disease.

Graft-versus-host disease (GVHD) occurs in a number of clinical settings. It is well recognized after bone marrow transplantation, an increasingly used therapeutic option for haematological disorders. Chronic GVHD, occurring at an interval greater than 100 days post-transplant, has many systemic manifestations, but it is the cutaneous manifestations which are most frequent and often most troubling to the patients. In this review article, the wide spectrum of cutaneous chronic GVHD (including involvement of hair, nails and mucosae), and its complications and associations are discussed. The clinical and histological features and management guidelines are presented to assist the dermatologist with diagnosis and treatment of this condition.

Bone Marrow Transplantation↗

PubMed1996

Documenting laryngeal change following prolonged loud reading. A videostroboscopic study.

This study investigated the effects of prolonged loud reading on trained and untrained subjects. Subjects were eight young women singers, and eight young women with limited musical experience. Each subject underwent videostroboscopic examination prior to and following 1 h of prolonged loud reading. The pretest and posttest videotaped samples were randomized and presented to three experienced judges, who evaluated various aspects of laryngeal appearance and vibratory characteristics. Analyses of group data revealed that untrained subjects showed a small but significant increase in amplitude of vocal fold excursion following the experimental task. No significant differences were noted in the trained singer group. When individual variation was analyzed, it was found that most subjects did not show many changes from pretest to posttest. It was concluded that a l-h loud-reading task was not sufficient to induce notable laryngeal alterations.

Adult↗

PubMed1995

Risk of cardiac events in family members of patients with long QT syndrome.

OBJECTIVES: This study sought to identify risk factors for cardiac events (syncope, aborted cardiac arrest or sudden cardiac death) in family members of patients with the long QT syndrome. BACKGROUND: Patients with the long QT syndrome are known to be at high risk for cardiac events. Whenever the first member of a family is identified as having the long QT syndrome (proband), there is concern regarding the likelihood of cardiac events in other family members. METHODS: A multivariate logistic regression model was used to evaluate the risk of cardiac events in 637 family members who were first- and second-degree relatives of 151 probands with the long QT syndrome and in a subset of 513 family members who were not receiving beta-adrenergic blocking agents. There were 293 first-degree (46%) and 344 second-degree relatives (54%) (293 men [46%], 344 women [54%]). Fifteen percent of the family members had a corrected QT interval (QTc) > 0.44 s, and relative tachycardia and bradycardia were observed in 12% and 25%, respectively. RESULTS: The risk of cardiac events occurring before age 40 in family members not taking beta-blockers was influenced by the QTc interval (odds ratio [OR] 1.18/0.01 increase in QTc value; 95% confidence interval [CI] 1.12 to 1.24), relative tachycardia (OR 2.21, 95% CI 0.97 to 5.02) or bradycardia (OR 2.24, 95% CI 1.10 to 4.56) and an interaction term combining gender and closeness of the relationship to the proband (OR for female first-degree relative 3.23 vs. all second-degree relatives, 95% CI 1.67-6.22). CONCLUSIONS: Female first-degree relatives of patients with the long QT syndrome have a higher risk of cardiac events than male first- or second-degree relatives, independent of recorded electrocardiographic findings. Not only bradycardia, but also tachycardia increases risk of cardiac events in family members of patients with the long QT syndrome.

Adolescent↗

PubMed1995

Congruence in personality between clinician and client: relationship to ratings of voice treatment.

This study examined relationships between ratings of voice therapy sessions and clinician and client personality characteristics as measured by the Myers-Briggs Type Indicator. Nineteen clinician-client pairs were rated on behaviors demonstrated in two therapy sessions. Results indicated that client variables of thinking-feeling and judgment-perception were related to amount of clinician feedback, client eye contact, ratio of clinician-client eye contact and amount of clinician explanation, clarity of explanation, clinician's initiative, and client eye contact, respectively. Clinicians' sensing-intuition was related to the amount of feedback to client and quality of the task sequence. Clinician's judgment-perception was related to amount of explanation and client's attention to clinician. Similarity in clinician-client sensing-intuition was related with task involvement of the client, clinician's attention to client, and clinician eye contact. Similarity in judgment-perception was related to greater use of counseling. Similarity in thinking-feeling was related to low amounts of clinician eye contact.

Humans↗

PubMed1993

Consistency in clinicians' and clients' behavior in voice therapy: an exploratory study.

The primary purpose of this study was to investigate consistency in clinicians' behaviors during two voice therapy sessions. The secondary purpose was to examine relationships between ratings of clinicians' and clients' behaviors. Each clinician (n = 7) was observed working with two different clients. Two experienced evaluators, using the Adjective Checklist and five-point semantic differential scales, rated clinicians and clients. Results indicated that 6 of 10 aspects of therapy studied were found to be relatively inconsistent, with the pace of therapy being the least stable. Ratings of individual clinician traits (e.g., favorable, unfavorable, intraception) were the most stable.

Adult↗

PubMed1993

Intervention with young voice users: a clinical perspective.

This diverse group is described in relation to life stage, short- and long-range performance objectives, and lifestyle factors pertinent to vocal health. Physical, behavioral, cognitive, and psychosocial issues relevant to assessment and intervention will be addressed. The possible dissonance between a clinician's developmental perspective and a client's immediate pragmatic concerns is discussed. In addition, the specific challenges of dealing with adolescents (e.g., the influence of the peer group, the emergence of autonomy, the redefinition of relationships with significant adults, and the vulnerability of the mechanism) are related to clinical problem solving.

Child↗

PubMed1992

Subclinical mastitis in ewes and its effect on lamb performance.

Two studies were conducted to 1) assess the effectiveness of the California mastitis test (CMT) relative to direct microscopic somatic cell count (DMSCC) and(or) somatic cell count (SCC) procedures for detecting subclinical mastitis in ewes, 2) determine the incidence of subclinical mastitis based on repeated or single sample measures and organisms associated with the inflammation, and 3) assess the relationship between milk quality measures and lamb performance. The relationship between DMSCC and SCC scores was significant (P less than .01); 90% of the variation in DMSCC scores was accounted for by SCC scores. In contrast, CMT scores accounted for only 26% of the variation in DMSCC and 30 to 34% of the variation in SCC scores. Incidence of inflammation varied from 17 to 50% of ewes tested, depending on the study and the method of assessment. Staphylococcus species were cultured from 14/41 samples tested, with cultures of Streptococcus species (3/41) and Micrococcus species (1/41) also present. The effect of subclinical mastitis in ewes on lamb performance was minimal when assessed by regressing lamb weights on subclinical mastitis and milk quality scores. In conclusion, growth performance of lambs in a management system where they had access to supplemental feed was not influenced by the quality of milk produced by ewes, or by the degree of subclinical mastitic inflammation present when they suckled.

Animals↗

PubMed1988

Occurrence, characteristics and prognostic significance of early postacute myocardial infarction angina pectoris.

To determine the incidence, clinical characteristics and prognostic significance of early spontaneous angina after acute myocardial infarction (AMI), the database involving the 867 participants of the Multicenter Post-AMI Program, who were followed for 1 to 4 years after AMI, was analyzed. Two hundred eighty-six patients (33%) had in-hospital postinfarction angina. During a mean follow-up of 31 months, patients with postinfarction angina were more frequently (p less than 0.001) hospitalized for cardiac causes and underwent coronary artery bypass graft surgery; however, their cardiac mortality rates at 1 year (8.4%) and at 4 years (14.3%) were not significantly different from those among patients without postinfarction angina (7.1 and 12.9%, respectively). The only anginal characteristic found to be associated with increased subsequent cardiac mortality (17.9% at 1 year, 39.2% at total follow-up) was high frequency angina (greater than or equal to 1 daily episodes). High frequency angina occurred in a small subset of 28 patients (3.2% of the study population, 9.8% of patients with postinfarction angina). Clinical variables representing higher grades of mechanical dysfunction and electrical instability after infarction were significantly more common among patients with high frequency angina than among those with low frequency angina. Cox survivorship analysis revealed that high frequency angina made a significant contribution to the risk of post-AMI cardiac death (hazard ratio 2.5, p = 0.01), which was independent of the effect of predischarge reduced radionuclide ejection fraction and Holter-recorded frequent or repetitive ventricular premature complexes.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1985

Acceptability and intelligibility of tracheoesophageal speech.

The original Blom-Singer voice prosthesis, introduced in 1979, has been recently modified to provide lower airway resistance. A tracheostoma breathing valve, introduced in 1982, permits unrestricted two-way breathing, yet eliminates the need for manual occlusion of the stoma. To date, the acceptability and intelligibility of tracheoesophageal (TE) speakers, using these prostheses, has not been extensively studied. Forty-six naive listeners rated the acceptability and intelligibility of 15 TE speakers, all of whom were wearing the tracheostoma breathing valve and a prototype low-pressure prosthesis. Acceptability was judged on an equal-appearing interval scale. Intelligibility judgments were based on randomized word lists of 50 items. Results suggest a high level of acceptability and intelligibility among both male and female TE speakers.

Evaluation Studies as Topic↗

PubMed1984

Localization of calmodulin in differentiating pulmonary type II epithelial cells.

Pulmonary surfactant is synthesized by alveolar type II pneumonocytes and stored in inclusions called lamellar bodies. In the present study we have investigated the role of the calcium-binding protein, calmodulin, in regulating surfactant secretion in differentiating rat fetal type II pneumonocytes. Lamellar body secretion is stimulated in differentiating type II cells in vitro by the calcium ionophore, A23187. A23187-induced secretion is blocked by the phenothiazine drugs, trifluoperazine and chlorpromazine, but is unaffected by the inactive analogs, trifluoperazine sulfoxide and chlorpromazine sulfoxide. Immunofluorescence studies on cultured type II pneumonocytes show that the percentage of Nomarski-dense intracellular granules, which stain positively with anticalmodulin antibody, increases when the cells are stimulated with the calcium ionophore, A23187. Since these Nomarski-dense granules are positively stained by phosphine-3R, these results indicate that increased amounts of immunoreactive calmodulin appear associated with lamellar body surfaces when the cells are stimulated for secretion. In addition, ultrastructural localization of calmodulin on isolated lamellar bodies using protein A-colloidal gold indicates that calmodulin is present on their outer surfaces. The endogenous calmodulin present on the isolated lamellar bodies is not removed by treatment of the lamellar bodies with ethylene glycol bis(beta-aminoethyl ether)-N,N'-tetraacetic acid. Using the same localization technique, we found that isolated lamellar bodies are capable of binding exogenously added calmodulin in the presence of calcium. Taken together, these results implicate calmodulin in pulmonary surfactant secretion.

Animals↗