Biomedical subjects

R R Martin

Publications and source records attributed to R R Martin.

At least 91 records · Page 5Linked to original sources

PubMed1986

Chemiluminescence of lung macrophages and blood leukocytes in sarcoidosis.

A luminol-enhanced chemiluminescence assay was used to measure light elaborated by peripheral blood polymorphonuclear leukocytes (PMNs) and by pulmonary alveolar macrophages (PAMs) from 14 healthy, normal subjects and 16 patients with sarcoidosis. Resting peripheral blood PMNs (incubated only in medium) from patients with sarcoidosis generated substantially more chemiluminescence than PMNs from normal control subjects (p = 0.002). With zymosan stimulation, greater chemiluminescence was produced by PMNs from untreated patients with sarcoidosis than from normal subjects (p less than 0.05), whereas no differences were noted with latex stimulation. Chemiluminescence for resting PAMs was not different between normal subjects and patients with sarcoidosis. However, PAMs from untreated patients with sarcoidosis had higher chemiluminescence with latex particle ingestion than PAMs from normal subjects (p less than 0.05), but no differences in PAM chemiluminescence were found when zymosan was the phagocytic particle. Increased chemiluminescence by PMNs and PAMs from patients with sarcoidosis may reflect phagocyte activation in the disease process.

Adult↗

PubMed1986

Cold air inhalation has a cumulative bronchospastic effect when inhaled in consecutive doses for progressively increasing degrees of ventilation.

In 12 asthmatic subjects, we compared the bronchoconstriction obtained with 3 methods of isocapnic inhalation of cold dry air (IICDA) on 6 visits, two visits for each method: Dose-response curves (DRC), which were obtained by asking the subjects to inhale at progressively increasing degrees of ventilation (7.5, 15, 30, 60 L/min and maximal voluntary ventilation [MVV] at a fixed breathing rate); free MVV, i.e., breathing frequency not set; same degree of ventilation as the last required for DRC (VEeq). Degrees of ventilation were significantly greater with the free MVV method. The percentage fall in FEV1 obtained by VEeq method was significantly lower than the changes recorded with the DRC and the MVV methods, the 2 latter being not significantly different. We conclude that IICDA induces a cumulative bronchoconstriction by the DRC method. However, the bronchoconstriction obtained with the latter method is not significantly different from the one obtained with the free MVV method.

Asthma↗

PubMed1985

Auditory stimulation, rhythm, and stuttering.

In a previous experiment, Martin, Siegel, Johnson, and Haroldson (1984) found that stutterers reduced their stuttering under amplified sidetone, but only if the amplified sidetone condition had been preceded by a condition of speaking in noise. The authors speculated that when stutterers were exposed initially to loud noise and its attendant reduction in stuttering, they became "sensitized" to reduced stuttering in any subsequent condition where their auditory feedback was modified. The current experiment tested that hypothesis with 24 adult stutterers divided evenly into three groups. One group of stutterers spoke with no auditory stimulation (quiet), then while receiving 100 dB SPL white noise, and then while receiving amplified sidetone (0, +10, +20 dB SPL). A second group spoke in quiet, then while receiving amplified sidetone, and then while receiving amplified sidetone again. A third group spoke in quiet, then while receiving rhythmic stimulation, and then while receiving amplified sidetone. Relative to vocal intensity in quiet, stutterers spoke with increased vocal intensity during noise, with decreased vocal intensity during amplified sidetone, and with no significant change in vocal intensity during rhythmic stimulation. Relative to stuttering frequency in quiet, subjects spoke with decreased stuttering frequency during loud noise and during amplified sidetone, but only when the amplified sidetone was preceded by the loud noise condition. These results are discussed in terms of the "sensitization" hypothesis.

Acoustic Stimulation↗

PubMed1985

Modification of listener-judged naturalness in the speech of stutterers.

This study investigated the effect of regular feedback of listener-judged speech naturalness ratings on the speech of stutterers. Six adult stutterers each participated in a time-series ABA experiment. During the treatment phase the stutterer was instructed to improve a clinician's rating, on a 9-point scale, of the naturalness of each 30-s interval of the stutterer's spontaneous speech. The results indicate that the naturalness ratings and stuttering for 5 of the subjects made favorable changes during the treatment phase. Analyses of the findings show that only some of the naturalness judgments were influenced by stuttering frequency and speech rate. A perceptual analysis of the speech of 2 subjects suggested that the speech naturalness ratings were also probably influenced by other less obvious variables.

Adolescent↗

PubMed1985

Inhibition of Chlamydia trachomatis growth in McCoy, HeLa, and human prostate cells by zinc.

Zinc salts (10(-4) and 10(-5) M) inhibited the number of Chlamydia trachomatis inclusions in McCoy, HeLa, and primary human prostate epithelial cell cultures. Addition of zinc salts 1 h before or 24 h after inoculation with C. trachomatis was found to inhibit growth. Both C. trachomatis serotype D and a lymphogranuloma venereum strain were inhibited by the zinc salts. Although the mechanism of inhibition is not known, the continued presence of the zinc appeared necessary for maximal effect. At the concentrations tested, zinc was not directly toxic to the McCoy cells. These results suggest that the levels of zinc in prostatic secretions may be sufficient to preclude the recovery of chlamydia in the diagnostic laboratory or to inhibit chlamydia from infecting the prostate in vivo.

Cell Line↗

PubMed1985

Slope of the dose-response curve to inhaled histamine and methacholine and PC20 in subjects with symptoms of airway hyperexcitability and in normal subjects.

Slopes of the dose-response curves to inhaled histamine or methacholine and PC20 were compared in 14 subjects with symptoms of bronchial hyperexcitability and in 10 normal subjects. Slopes were obtained by analyzing curves with 3 to 6 points by the least squares method. Only curves with satisfactory correlation coefficients corresponding to p values less than 0.05 were kept for analysis. Twelve of the 14 subjects with symptoms of bronchial hyperexcitability and 1 of the 10 normal subjects had slopes greater than 20 (percent change in FEV1/log histamine or methacholine concentration) (chi-square = 13.5, p less than 0.001). Eleven of the 14 subjects with symptoms of bronchial hyperexcitability and 1 of the 10 normal subjects had PC20 results less than or equal to 16 mg/ml (chi-square = 11.0, p less than 0.001). It is concluded that, using the method described in our study, slopes of the dose-response curve to inhaled histamine or methacholine are different in subjects with and without symptoms of bronchial hyperexcitability.

Adult↗

PubMed1985

Kinetics of the recovery of airway response caused by inhaled histamine.

The time course of recovery from airway response induced by the inhalation of progressively doubling doses of histamine phosphate (3 to 4 depending on the subject) was studied in 8 asthmatic subjects by serial measurements of lung resistance (RL). For every subject, the time required for functional recovery became longer with increasing histamine doses and/or degrees of airway response. The slopes of the curves obtained from a single exponential fit relating time on the abscissa and functional recovery on the ordinate were significantly (F = 4.9 to 50.0, p less than 0.01) and progressively lower in 7 of 8 instances. This suggested a multiple compartment model, which was confirmed (r2 greater than or equal to 0.95) in 5 subjects by applying a double exponential regression that provided the most satisfactory fit. We conclude that the recovery from airway response caused by inhaled histamine is longer with increasing doses of histamine and/or degrees of airway response. A double-compartment model, a fast one followed by a slow one, fit this pattern of recovery in 5 of the 8 subjects.

Adult↗

PubMed1984

Effect of sodium cromoglycate on histamine inhalation tests.

Sixteen adult asthmatic subjects in a clinical steady state were included in the study. On day 1, after baseline assessment of spirometry (FEV1, FEV1/FVC, FEF25-75), they underwent three to four consecutive inhalation tests using twofold increasing doses of histamine to measure the provocative concentration causing a fall in FEV1 of 20% (PC20). Baseline FEV1 was back to +/- 5% of the initial assessment before each histamine inhalation test (HIT). On days 2, 3, and 4, after baseline spirometry which confirmed that FEV1 was within 10% of initial day 1 assessment, placebo-lactose (P) or 40 mg of sodium cromoglycate (SCG) were nebulized in a double-blind randomized 4.3.1. two-treatment crossover study design. Ten minutes later, spirometry was repeated and followed by an HIT. Baseline spirometry was not significantly different on each day or after P and SCG. There was no statistical difference between the geometric means of the three or four PC20's done on day 1, indicating that there is no tachyphylaxis induced by repeated HIT. There was no statistical difference between mean PC20 after P (0.52 +/- 3.3 (SD) mg/ml), after SCG (0.50 +/- 3.2), and of the three to four HIT done on day 1 (0.40 +/- 3.6). We conclude that in asthmatic subjects SCG has no acute bronchodilator effect and does not alter the response to inhaled histamine.

Adult↗

PubMed1984

Stuttering and speech naturalness.

The present study was concerned with the development and evaluation of a scale of speech naturalness. Speech samples were recorded of the typical speech of 10 stutterers, 10 stutterers speaking without stuttering under 250-ms delayed auditory feedback (DAF), and 10 nonstutterers speaking normally. Using a 9-point scale, 30 unsophisticated listeners judged how natural the speech sounded in each sample. Results indicated that the stutterer samples were judged as sounding significantly more unnatural than the nonstutterer samples, and the DAF stutter-free samples were judged as sounding significantly more unnatural than the nonstutterer samples. The stutterer and DAF stutter-free samples were not judged as sounding significantly different in terms of speech naturalness. Interrater reliability, interrater agreement, and rater consistency for judging speech naturalness were all satisfactory.

Adult↗

PubMed1984

Sidetone amplification, noise, and stuttering.

In the present study, 24 stutterers and 24 matched nonstutterers spoke spontaneously under conditions of quiet, noise (60, 80, 100 dB SPL re .0002 dynes/cm2), and amplified sidetone (0, +10, +20 dB SPL re .0002 dynes/cm2). All 24 stutterers and 23 of the 24 nonstutterers experienced a decrease in vocal intensity from quiet to 20 dB amplified sidetone. All the nonstutterers and 23 of the stutterers experienced an increase in vocal intensity from quiet to 100 dB noise. As a group, the stutterers experienced a significant decrease in stuttering in the noise conditions; however, with regard to the amplified sidetone conditions, only those stutterers who experienced noise first showed a significant reduction in stuttering during amplified sidetone.

Acoustic Stimulation↗

PubMed1984

Histamine phosphate has a cumulative effect when inhaled at five minute intervals.

As the duration of bronchoconstriction induced by inhaled histamine phosphate is greater than five minutes, a study was carried out to determine whether this leads to a cumulative effect when histamine is inhaled at five minute intervals as in standardised procedures. Fourteen clinically stable adult asthmatic subjects were studied. In the first part of the study (the noncumulative stage) they inhaled doubling concentrations of histamine until appreciable bronchoconstriction occurred (changes close to 50% in lung resistance for seven subjects and 15% in forced expiratory volume in one second for seven others). After functional recovery the last concentration of histamine was nebulised on two more occasions, allowing for functional recovery after each nebulisation. In the second part of the study (the cumulative stage) subjects inhaled, depending on their responsiveness, three to eight consecutive doses of the histamine concentration last administered in the non-cumulative stage, these doses being administered at five minute intervals, without recovery. The cumulative effect was assessed by linear regression analysis of the changes in the specific functional indices, all the values obtained during the non-cumulative stage being given the score 0 and those obtained during the cumulative step scores of 1, 2, etc. In all but one instance significant (p less than 0.01) correlations were obtained and the slopes were positive, thus showing a cumulative effect. It is concluded that histamine has a cumulative bronchoconstrictor effect if inhaled at five minute intervals once appreciable bronchoconstriction has been reached.

Adult↗

PubMed1984

Bronchial responsiveness to methacholine and effects of respiratory maneuvers.

Eight asthmatic and six normal subjects had methacholine chloride inhalation tests on two visits. On first assessment the provocative concentration causing a 20% fall in forced expiratory volume in 1 s (PC20FEV1) was measured. On the second visit the provocative concentration causing a 35% fall in specific lung conductance (PC35sGL) was obtained in addition to the PC20FEV1. Lung resistance was continuously monitored to evaluate the bronchomotor effect of FEV1 maneuver. Results of PC20FEV1 were within one single twofold concentration on the two visits. In all subjects but one PC35sGL was lower than PC20FEV1, and in 10 instances this difference was superior to a single twofold concentration. The bronchodilator effect of FEV1 maneuver was significantly although loosely related to base-line airway caliber and excitability. However, we were unable to show a significant relationship between the differences between PC20FEV1 and PC35sGL and this bronchodilator effect. This suggests that other factors may explain the greater sensitivity of PC35sGL compared with PC20FEV1.

Asthma↗

PubMed1984

Functional effects of pneumonectomy and bilobectomy for lung cancer.

28 patients with lung cancer had pulmonary function studies before and 3 months to 3 years after pneumonectomy or bilobectomy. Preoperative profiles showed a slight obstructive pattern with air trapping and perturbated gas exchange. The obstructive pattern was not related to endoscopy findings, but the alveoloarterial gradient oxygen gradient was smaller in those with complete lobar occlusion. After surgery, the volume loss was related to the amount resected, being greater after right pneumonectomy than after left pneumonectomy and least after bilobectomy. The obstructive pattern remained unchanged. Diffusion of carbon monoxide decreased significantly less than volumes after pneumonectomy but proportionally after bilobectomy. Those with increased alveoloarterial oxygen gradient or increased physiologic dead space experienced a significant improvement of their gas exchange after surgery.

Adult↗

PubMed1983

Immune responses in serum and respiratory secretions following vaccination with a live cold-recombinant (CR35) and inactivated A/USSR/77 (H1N1) influenza virus vaccine.

One hundred adult volunteers were administered inactivated vaccine (20 micrograms/0.5 cc) intramuscularly (IM) or intranasally (IN), or 10(4.7) TCID50 of a live cold-adapted vaccine (CR35) IN. Microneutralization (Nt) and radioimmunoprecipitation methods were employed to measure hemagglutinin antibody responses in sera, nasal washes, and in bronchopulmonary lavage fluids. In unprimed recipients, the relative frequency of serum antibody response and magnitude of rise was highest following the IM-inactivated vaccine (100%) and lowest after IN-live vaccine (29%). However, in individuals with pre-existing antibody, the three vaccines given were comparably immunogenic. Occurrences of secretory IgA hemagglutinin antibody in nasal washings were more frequently associated with topical administration of live or inactivated vaccine, whereas, IgG hemagglutinin antibody responses occurred with equal frequency in nasal washings in all three vaccine groups. Analysis of the hemagglutinin antibody responses in the lower respiratory tract showed that the IN-live vaccine favored the induction of secretory IgA hemagglutinin antibody and the IM-inactivated vaccine stimulated a more frequent IgG hemagglutinin antibody response.

Administration, Intranasal↗

PubMed1983

Histamine dose-response curves in asthma: reproducibility and sensitivity of different indices to assess response.

In 18 clinically stable asthmatic patients histamine inhalation challenges were performed with a Wright's nebuliser and tidal volume breathing for two minutes on two to four occasions for each subject at a maximum interval of two weeks. The response was measured in terms of specific lung conductance (sGL) by the subtraction technique, maximum partial and maximum complete expiratory flow at 40% and 50% of vital capacity respectively (Vmax40p and Vmax50c), and FEV1 from the maximum flow-volume curve. Dose-response curves were analysed for (1) provocative concentration (PC) of histamine causing a 20% fall in FEV1 and a 40% change in the other measurements; (2) threshold concentration (TC)--the concentration at which changes in the measurement exceed 2 SD from control values; (3) reactivity (R)--the slope of the dose-response curve beyond TC. We found that PC20-FEV1 was the most reproducible index, the 95% confidence intervals based on a single determination being +/- 1.6 single two-fold concentration difference. PC20-FEV1 was more reproducible than PC values for other measurements and more reproducible than any of the TC values. The 95% confidence intervals based on a single determination of R varied from +/- 52% to +/- 74% change/log histamine concentration. Both sGL and Vmax40p detected the bronchoconstrictor response assessed by PC and TC at a significantly lower histamine concentration than FEV1 (p less than 0.01 and p less than 0.05 respectively). PC and TC results showed a significant correlation, but neither were correlated with R.

Adult↗

PubMed1983

Time course of the bronchoconstriction induced by inhaled histamine and methacholine.

Eleven asthmatic subjects inhaled doubling concentrations of histamine until a near sixfold increase in total pulmonary flow resistance had been reached. This last concentration (C6) of histamine and methacholine was administered on two subsequent separate visits. Specific lung conductance (sGL) dropped to 18.6 +/- 7.9 (SD) and 19.1 +/- 10.3% of initial value after histamine and methacholine, respectively (NS). Whereas the peak action occurred in a similar interval (1-4 min), the mean duration of the subsequent plateau, defined as values of sGL within 20% of the maximum fall was 16.8 +/- 9.8 min for histamine and 74.6 +/- 53.7 min for methacholine (P less than 0.01). The recovery phase from the end of the plateau to base line lasted 25.5 +/- 14.4 min for histamine and 56.7 +/- 38.3 min for methacholine (P less than 0.01). The duration of plateau and recovery phases were not linked with base-line sGL, maximum fall in sGL, or C6. We conclude that for the same induced bronchoconstriction methacholine has a more prolonged action than histamine.

Adolescent↗

PubMed1983

Reference values of the provocative concentrations of methacholine that cause 6% and 20% changes in forced expiratory volume in one second in a normal population.

The provocative concentrations of inhaled methacholine that cause 6% (PC6) and 20% (PC20) falls in forced expiratory volume in one second (FEV1) were assessed in a population of 100 nonsmoking persons, equally distributed for sex, who ranged uniformly from 20 to 60 yr of age. These subjects had no respiratory symptoms, rhinitis, atopic history, or familial history of asthma. Single twofold dilutions of methacholine from 2 to 128 mg/ml were used; 81 and 34 subjects, respectively, showed PC6 and PC20 values less than 128 mg/ml. Eight subjects had PC20 values less than 16 mg/ml. In these subjects, the test had a good reproducibility (r = 0.92) when we repeated it, and serial measurements of peak expiratory flow rates did not suggest asthma. The fact that PC6 was related, although loosely, to baseline FEV, FEV/FVC, and forced expiratory flow during the middle half of the FVC (FEF) and that 4 of the 8 subjects with PC20 values less than 16 mg/ml had lower values of FEF might suggest that responsiveness to methacholine is partially linked with baseline airway caliber.

Adult↗

PubMed1983

Kinetics of platelet adhesion and thrombus growth.

Epifluorescent microscopy was used to monitor the adhesion of platelets and the growth of platelet aggregates on collagen-coated glass tubes perfused with whole blood. The maximum basal length and width of the aggregate size increased linearly with time, growing symmetrically transverse to the direction of flow and asymmetrically in the plane longitudinal to the direction of flow. Aggregates had elliptical bases, with the major axis parallel to the direction of blood flow. These studies provide an experimental approach to studies of the kinetics of platelet interaction with artificial surfaces and give further support to the concept that blood flow has a major effect on the development of platelet thrombi.

Collagen↗