Search PubMed⌕ Search

Biomedical subjects

B A Phillips

Publications and source records attributed to B A Phillips.

At least 55 records · Page 3Linked to original sources
PubMed1990

16S rRNA sequence determination for members of the genus Carnobacterium and related lactic acid bacteria and description of Vagococcus salmoninarum sp. nov.

The phylogenetic interrelationships of members of the genus Carnobacterium and some atypical lactobacilli isolated from diseased salmonid fish were investigated by using reverse transcriptase sequencing of 16S rRNA. The four species Carnobacterium piscicola, Carnobacterium divergens, Carnobacterium gallinarum, and Carnobacterium mobile exhibited a high degree of sequence similarity with each other (ca. 96 to 98%) and formed a phylogenetically coherent group that was quite distinct from all other lactic acid bacteria. The sequence data clearly demonstrated that carnobacteria are phylogenetically closer to the genera Enterococcus and Vagococcus than to members of the genus Lactobacillus. The strains from fish were found to be phylogenetically related to the genus Vagococcus and represent a new species, Vagococcus salmoninarum. The type strain of Vagococcus salmoninarum is strain NCFB 2777.

Animals↗
PubMed1990

Nocturnal bruxing events in healthy geriatric subjects.

Thirty healthy geriatric subjects were studied during a single night of sleep in a sleep laboratory. Unilateral masseter muscle activity was recorded in addition to the standard polysomnographic study. The geriatric subjects in this study exhibited fewer bruxing events than other subjects reported in the literature. Certain conditions that have not been previously investigated, such as sleep position, type of bruxing event, and relationship to the state of the dentition, are reported.

Aged↗
PubMed1990

Treatment of obstructive sleep apnea. A preliminary report comparing nasal CPAP to nasal oxygen in patients with mild OSA.

Nasal CPAP is presently accepted as first-line therapy for obstructive sleep apnea, but a significant minority of patients do not tolerate nasal CPAP. The purpose of this study was to compare the benefits of nasal CPAP, nasal oxygen (O2), and placebo (air) using patients as their own controls. We studied eight men, aged 33 to 72 (mean 57 years), who had mild obstructive sleep apnea. To be eligible for study, patients had to have an apnea plus hypopnea index greater than or equal to 5, plus one or more of the following: blood pressure greater than 150/95 mm Hg, multiple sleep latency test mean score less than or equal to 10 minutes, or significant nocturnal cardiac ectopy. After a baseline study, patients received a month each of nocturnal O2 at 4 LPM and air at 4 LPM, presented in random order. The third month of treatment consisted of nasal CPAP (range 2.5 to 12.5 cm H2O). Patients underwent evaluation at baseline and after each month of treatment. It was concluded that oxygen was more effective in improving oxygenation and hypopneas than is nasal CPAP. However, oxygen did not reduce apneas or improve daytime hypersomnolence as well as nasal CPAP in patients with mild OSA. Oxygen might be considered as an alternate form of treatment for patients who are not hypersomnolent, or as an adjunct to nasal CPAP.

Adult↗
PubMed1990

The 1989 Kentucky Hospital Smoking Policy Survey.

Kentucky leads the nation in percentage of smokers (32.5%), years of potential life lost due to smoking-related illness, and burley tobacco production. In view of this, we sought to determine current practice regarding smoking policies in Kentucky hospitals. Acute care and psychiatric hospitals were identified through the 1988 Kentucky Hospital Association Directory and the Paired Community Laboratory System. One hundred seven institutions were sent standardized questionnaires. An additional 16 hospitals were contacted by phone only. All mail and telephone surveys were directed towards the institution's president, administrative director, or CEO. Eighty-one (75.7%) of those contacted by mail responded to the survey. The 26 non-responding institutions were then contacted through a telephone survey. Thus, 100% of acute care hospitals in Kentucky participated in the survey. Of the 123 institutions surveyed, 110 (89.4%) have some type of smoking policy. Of those 110 hospitals with smoking policies, only 6 totally prohibited smoking on the premises. The 13 hospitals without any form of policy were queried about future plans for smoking policies. Of these, only 4 had no plans to work on a hospital smoking policy. Of the 123 hospitals surveyed, 100 do not sell tobacco products. There were no statistically significant differences between the numbers of beds, average length of stay, occupancy rate, or county populations in Kentucky hospitals that do not sell tobacco versus those hospitals that do sell tobacco.(ABSTRACT TRUNCATED AT 250 WORDS)

Data Collection↗
PubMed1990

Home monitoring of theophylline levels: a novel therapeutic approach.

This pilot clinical investigation was conducted to compare a home therapeutic drug-monitoring (TDM) method for theophylline blood levels and a traditional TDM method with respect to various patient outcome factors. Outpatients with chronic obstructive pulmonary diseases (COPD) or asthma who were receiving long-term theophylline therapy were randomized to one of two groups: home TDM or traditional TDM (controls). Patients in the former group monitored their serum theophylline levels at home over 6 months. Patients in both groups completed survey instruments, including questionnaires, visual analog scales, and other psychosocial measures, at designated times throughout the study period. Pulmonary function tests and dyspnea index scores were evaluated at each clinic visit. Results indicated a significantly lower (p less than 0.05) number of changes in concomitant drug therapy in the home TDM group compared with controls. Other indicators that showed a trend toward more favorable outcomes in the home TDM group included symptomology, percentage of levels within the therapeutic range, patient attitudes regarding participation in health care management, and pulmonary function test results. Home monitoring prevented unnecessary clinic visits in several instances when theophylline dosage adjustments were based on telephone reports from patients. The utility of a home TDM method for theophylline has not been reported previously despite potential for broad applications. Findings from this preliminary study may support the use and feasibility of state-of-the-art methodologies in carefully selected subpopulations outside the confines of the hospital or clinic setting.

Ambulatory Care↗
PubMed1989

Isocapnic hypoxemia and neuropsychological functioning.

We evaluated the cognitive effects of hypoxemia independent of hypocapnia in 20 right-handed male subjects using a battery of brief neuropsychological tests. Results of a profile analysis indicated that performance during hypoxia was reliably different for Digit Symbol and Finger Tapping tests. Trend analysis demonstrated a significant linear pattern for Finger Tapping results, such that lower levels of oxygen were associated with slower rates of tapping. No significant trends were observed for Digit Symbol results. The observation of hypoxic effects on Digit Symbol and Finger Tapping tests is consistent with previous findings of neuropsychological changes secondary to hypoxia. The negative results observed for the remaining tests are inconsistent with past literature. It is likely that methodological differences contributed to these discrepancies, including previous reliance on inspired air to index hypoxemia rather than monitoring arterial oxygen saturation directly and failure to control for differences in CO2 levels during induced hypoxia. These variables should be controlled in future research.

Adult↗
PubMed1989

Sleep-disordered breathing in healthy aged persons: one-year follow-up of daytime sequelae.

We studied the waking medical, sleep, and psychological status of 28 healthy older persons who had undergone nocturnal polysomnography and daytime assessment approximately 1-year earlier. In a previous report based on this sample, we found that sleep-disordered breathing (SDB) indices were not related to concurrent measurements of daytime functioning. However, in the present study, we observed relationships between the original SDB indices and several measures of cardiopulmonary functioning obtained 1 year later. At follow-up, subjects with originally high levels of SDB had significantly higher systolic blood pressure and poorer pulmonary function test results, were more likely to report irregular heartbeats in the previous year, and had experienced more disruptive snoring than the remaining subjects. When combined with other recent data, these results raise the possibility that SDB exerts an insidious pathological influence on the health and daytime functioning of otherwise healthy older persons.

Aged↗
PubMed1988

The effects of hypoxemia on cardiac output. A dose-response curve.

To establish a dose-response curve for the effects of isocapnic hypoxemia on cardiac output (CO), we studied 20 healthy men, aged 20 to 34 years, using a tight-fitting face mask and an isocapnic partial rebreathing system (a modified anesthesia machine). We blended oxygen and hypoxic gas to achieve arterial oxygen saturations (SaO2) of 80, 85, and 90 percent; subjects also breathed 100 percent oxygen and room air (RA). Target SaO2 and end-tidal carbon dioxide were continuously monitored using an ear oximeter and CO2 gas analyzer. Subjects experienced the five SaO2 measurements in random order. CO was measured noninvasively at approximately two-minute intervals, using continuous-wave Doppler echocardiography. Mean cardiac output increased with increasing hypoxemia from 6.84 L/min at FIo2 1.0 to 8.44 L/min at SaO2 80 percent (p less than 0.0005); the increase was entirely due to increased heart rate. We concluded that cardiac output increases significantly in a dose-response manner in response to acute isocapnic hypoxemia in normal persons.

Acute Disease↗
PubMed1987

The acute effects of the enkephalin analogue BW 942C in humans.

BW 942C hydrochloride is an enkephalin analogue that has exhibited a wide separation between antidiarrheal dosages and dosages inducing adverse effects in animals. This has likewise been the case in humans when administered orally. In this study, the safety and tolerance of single 0.5-mg doses of intravenous BW 942C compared with placebo were assessed in humans. Four healthy male volunteers received BW 942C, and two received placebo. The effects of BW 942C on serum growth hormone (GH), luteinizing hormone (LH), prolactin (PR), and follicle-stimulating hormone (FSH) were assessed in three of these volunteers. No significant changes were apparent in vital signs, in clinical chemistry, hematologic and urine studies following BW 942C administration. BW 942C did not appear to alter mood as assessed by two psychologic mood scales. Prolactin levels tended to increase in volunteers receiving BW 942C two hours postinfusion. Luteinizing hormone concentrations decreased slightly at two and six hours. No trends in FSH or GH could be identified. Pulmonary function testing did not reveal any significant changes in oximetry, spirometry, or plethysmography in any of the subjects. A marked decrease in CO2 responsiveness in two subjects may indicate that BW 942C has mild ventilatory depressant effects. Untoward effects experienced in volunteers receiving BW 942C included heaviness in the limbs, nasal stuffiness, mouth dryness, facial flushing, skin rash, and prickling sensations. These effects bear a striking similarity to those experienced after parenteral administration of other enkephalin analogues. Intravenous administration of BW 942C up to 0.5 mg appears safe from a laboratory, physiologic, and clinical perspective with unusual untoward effects that may preclude rational use of the drug by the parenteral route.

Adult↗
PubMed1987

A novel method for obtaining poliovirus 14 S pentamers from procapsids and their self-assembly into virus-like shells.

Poliovirus procapsids, isolated and partially purified from infected HeLa cells, were found to dissociate into 14 S pentamers following freezing at -20 degrees overnight. Unlike pentameric subunits isolated directly from virus-infected cells or those obtained by alkaline treatment of procapsids, the "freeze-dissociated" subunits self-assembled at room temperature into two kinds of empty capsids, one of which was similar to the shell of poliovirions as shown by its neutral pl, resistance to alkaline dissociation, and the presence of neutralization-related (N) epitopes. The other empty shell resembled that which was previously described as a self-assembled empty capsid (SAEC), as indicated by its acidic pl and absence of N antigenic determinants. At 37 degrees, the assembly reaction was significantly faster but only SAEC were formed. By following the assembly reaction by electron microscopy, intermediate structures were visualized; their relatively low amount at any given time was consistent with the previous hypothesis (J.R. Putnak and B.A. Phillips (1981), J. Virol. 40, 173-183) that initiation is the rate-limiting step in the morphogenesis of empty shells. The relevance of these findings to the morphogenesis of picornaviruses, and polioviruses in particular, is discussed.

Capsid↗
PubMed1987

Sleep-disordered breathing in healthy aged persons: possible daytime sequelae.

We assessed the overnight sleep and breathing as well as daytime medical, sleep, and psychological status of a group of 34 healthy older persons. Analyses indicated that sleep-disordered breathing (SDB) was not related to any aspects of daytime functioning as measured in this study and that persons with an apnea + hypopnea index (AHI) greater than or equal to 5 (M AHI = 14.6) were not significantly impaired relative to those with lower levels of SDB (M AHI = 1.0) on any aspect of daytime performance. We conclude that SDB occurring in healthy aged persons is probably not of immediate concern and that the use of a cutting score of AHI greater than or equal to 5 for diagnosis of sleep apnea syndrome is not indicative in healthy aged persons. However, these results may not be applicable to older persons who are not in the excellent state of health that was required for participants in our study.

Aged↗
PubMed1987

The effect of sleep loss on breathing in chronic obstructive pulmonary disease.

We have previously shown that one night of sleep deprivation results in significant deterioration of spirometric performance and ventilatory responsiveness to inhaled carbon dioxide in normal people. Since even a small decrease in pulmonary function may be clinically important in patients with chronic limitation of airflow, we undertook the present study to assess the effects of sleep loss on breathing in patients with chronic obstructive pulmonary disease (COPD). Criteria for inclusion in this study were a ratio of the forced expiratory volume in one second over the forced vital capacity (FEV1/FVC) of less than 60 percent, no hospital admission for pulmonary disease within two weeks of testing, stable (less than 30 percent variation) in tests of pulmonary function on two occasions within three months of testing, and no history of asthma. We studied 15 men (mean age, 57 +/- 3 years) on two consecutive mornings. Patients were studied with and without sleep deprivation in a randomized fashion. Patients were hospitalized for the study so that sleep deprivation, medications, smoking, and diet could be monitored and enforced. We found small but statistically significant falls in FEV1 (1.06 +/- 0.11 to 1.00 +/- 0.09 L; p less than 0.05) and in FVC (2.56 +/- 0.20 to 2.43 +/- 0.17 L; p less than 0.05) following sleep deprivation. Changes of similar magnitude which were not statistically significant occurred in maximal voluntary ventilation (MVV) and response to carbon dioxide. The arterial oxygen (PaO2) and carbon dioxide (PaCO2) tensions were not affected. Maximal expiratory pressure at the mouth increased slightly, but there was a fall in maximal inspiratory pressure (MIP) at the mouth. We conclude that sleep loss is associated with small but significant falls in FEV1 and FVC, as well as changes of similar magnitude in MVV, minute ventilation, and MIP in patients with severe COPD. Although the sleep loss which frequently accompanies exacerbations of COPD may be a slight additional stress of pulmonary reserve, a single night's loss of sleep in the patient with stable chronic airflow obstruction does not have major clinical consequences.

Aged↗
PubMed1987

Systemic cardiovascular and metabolic effects associated with the inhalation of an increased dose of albuterol. Influence of mouth rinsing and gargling.

We designed this investigation to assess the occurrence of systemic beta adrenergic side effects associated with the inhalation of an increased dose of the beta2 receptor agonist albuterol. Since therapeutic aerosols delivered by metered dose inhaler (MDI) are preferentially deposited in the mouth and pharynx, we wished to determine whether mouth rinsing and gargling with water might reduce the magnitude of such side effects by partially removing oral and pharyngeal drug residues. Serum glucose, insulin and potassium concentrations, forced expiratory volume in one second (FEV1), heart rate (HR), and blood pressure (BP) were measured as parameters of beta-adrenergic stimulation. Each of eight nonmedicated mild asthmatic patients was studied on two separate days after an overnight fast. Measurements were obtained twice before and then repeatedly at various times up to three hours after inhalation of ten albuterol doses (total dose approximately 1 mg) delivered by MDI. On either day the patient did, or did not, rinse the mouth and gargle after drug inhalation. Aerosol-administered albuterol significantly increased HR, FEV1, systolic BP and serum concentrations of glucose and insulin and lowered diastolic BP as early as five min after inhalation, indicating early systemic drug absorption. Peak changes in all measured parameters were observed within 30 min after treatment. Mouth rinsing and gargling removed 24 +/- 11 percent of the total albuterol dose delivered, but did not lower the magnitude or shift the time course of these side effects or bronchodilation. Our data suggest that cardiovascular and metabolic side effects are associated with the inhalation of an increased dose of albuterol and that mouth rinsing and gargling are not effective in reducing the magnitude of these systemic effects.

Adult↗
PubMed1986

Modulation of the expression of poliovirus proteins in reticulocyte lysates.

The translation of poliovirus RNA into specific viral proteins in mRNA-dependent reticulocyte lysates (MDLs) was found to be highly dependent on individual lysate preparations. Under optimal conditions, the first polypeptide detected was always P3-1b (formerly NCVP 1b), the product of the 3' portion of the poliovirus genome; the formation of P1-1a (formerly NCVP 1a) followed as shown by time-course and pulse-chase experiments. However, some lysates synthesized little or no P1-1a despite their ability to synthesize P3-1b and to translate normally other cellular and viral mRNAs. When an MDL competent in synthesizing P1-1a was diluted ca. twofold, while maintaining optimal concentrations of salts, tRNA, DTT, creatine phosphate, and amino acids, P1-1a formation was virtually eliminated, while the synthesis of P3-1b, presumably as a consequence of a more downstream initiation, was maintained. The synthesis of P1-1a in a diluted MDL was restored, and P3-1b synthesis suppressed, by the addition of a S10 fraction prepared from uninfected or virus-infected HeLa cells. Nuclease treatment and dialysis of the S10 fraction did not inhibit its activity. These findings indicate that individual MDLs either possess limiting quantities of, or occasionally are deficient in, a factor(s) that promotes the utilization of the presumed 5' proximal initiation site (the AUG at nucleotide position 781-783) and that a homologous factor(s) exists in HeLa cells. The implication of these findings for the strategy of poliovirus replication is discussed.

Animals↗
PubMed1986

Learning effect of repeated hypercapneic ventilatory response testing.

To determine whether hypercapneic ventilatory response (HCVR) is affected by repeated testing, the HCVR of 22 healthy subjects was determined daily for 4 consecutive days. The slope (S) of the HCVR increased to a maximum on Day 3, which was 14% greater than S on Day 1 (p less than 0.05). The increase in airway occlusion pressure during progressive hypercapnea (delta P0.1/delta PCO2) showed no significant change, indicating that although S and delta P0.1/delta PCO2 are both good measurements of ventilatory response, they are not totally interchangeable in normal subjects. A subgroup of 12 subjects (termed "increasers") was responsible for the overall increase in S. For this subgroup, S was significantly smaller on Day 1 than on each subsequent day. Increasers also had a significantly greater value of S on each day of the study than subjects who did not increase ("decreasers"). On Day 1, increasers' S was 3.77 +/- 1.31 L min-1 mm Hg-1, while decreasers' S was 2.46 +/- 1.00 (p less than 0.001). Some normal subjects demonstrate a learning effect during repeated daily testing of HCVR by the rebreathing technique, and those subjects whose S increases are those with large initial values of S.

Adult↗
PubMed1986

Biological activity and electron microscopy of poliovirus 14S particles obtained from alkali-dissociated procapsids.

Highly purified 14S subunit particles were obtained from alkali-dissociated poliovirus type 1 procapsids (naturally occurring empty capsids in poliovirus-infected cells) to compare their morphological and biophysical properties with those of naturally occurring 14S particles. Procapsid-derived 14S particles (PC-14S), like naturally occurring 14S particles, were capable of self-assembly into an empty shell in buffer or extracts from uninfected cells. These empty capsids always exhibited pIs more acidic than those of procapsids but were themselves distinguishable by their respective pIs. Nevertheless, if PC-14S or naturally occurring 14S particles were incubated with extracts made from poliovirus-infected cells, procapsidlike empty shells were formed. This clearly showed that the 14S particle, however obtained, possesses the information to form an empty shell of correct dimensions but of improper conformation, unless a factor present in poliovirus-infected cells is present. With the electron microscope, the PC-14S subunit frequently was seen as a pentagonal structure with a diameter of 20.4 +/- 1.4 nm, a size somewhat larger than expected for a subunit composing 1/12th of the poliovirus surface. Upon self-assembly in vitro, the empty shell formed exhibited a diameter of 29 +/- 1 nm and a wall thickness of ca. 6 to 7 nm. It was necessary to avoid CsCl banding of procapsids in their preparation as this treatment altered both their pI and their sensitivity to alkali dissociation into 14S subunits. The relevance of these findings to the nature and role of procapsids and the requirement for a morphopoietic factor in poliovirus morphogenesis is discussed.

Capsid↗
PubMed1986

Effect of sleep position on sleep apnea and parafunctional activity.

Parafunctional activity (toothgrinding, toothclenching and bruxism) is a common problem which may lead to masticatory muscle and temporomandibular joint pain, and may result from sleep arousal or disturbances. Sleep apnea is another common sleep disorder which results in disrupted sleep architecture and frequent arousals. Because sleep apnea leads to sleep arousals, and because sleep arousals are thought to result in increased parafunctional activity, we undertook the present study to determine the relationship between sleep apnea and parafunctional activity. We were also interested in assessing the effects of sleep posture on sleep disordered breathing and parafunctional activity. We prospectively studied 24 patients who were referred to the clinical sleep apnea laboratory for study. They underwent standard nocturnal polysomnographic examination; in addition, masticatory activity was measured with a masseter electromyogram. Patients slept in the supine and lateral decubitus positions. Nocturnal clenching was slightly higher in patients with sleep apnea than those without (12.2 vs 7.6 clenches/hr, p = 0.18), and there was a correlation between the clench index (CI) and apnea plus hypopnea index (A + HI) by linear regression (r = 0.49, p less than 0.05). There were significant falls in both the A + HI (64.4 +/- 28.8 vs 36.5 +/- 36.7, p = 0.02) and CI (12.5 +/- 12.1 vs 7.0 +/- 8.6, p = 0.04) in the lateral decubitus vs supine sleeping positions. We conclude that there is an association between obstructive sleep apnea and parafunctional activity, that sleep position affects the incidence of both sleep disordered breathing and parafunctional activity, and that analysis of apneas and hypopneas in both supine and lateral decubitus sleeping positions may be helpful.

Adolescent↗