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Biomedical subjects

P Miller

Publications and source records attributed to P Miller.

At least 19 recordsLinked to original sources
PubMed1992

Irradiation of the bovine mitochondrial F1-ATPase previously inactivated with 5'-p-fluorosulfonylbenzoyl-8-azido-[3H]adenosine cross-links His-beta 427 to Tyr-beta 345 within the same beta subunit.

The bovine heart mitochondrial F1-ATPase (MF1) is inactivated by 5'-p'-fluorosulfonylbenzoyl-8-azidoadenosine (8-N3-FSBA) with an apparent Kd of 0.47 mM at pH 8.0 and 23 degrees C in the absence of light. Irradiation of dark-inactivated enzyme with long-wavelength UV light produced cross-linked dimers and, to a lesser extent, trimers made up of alpha and beta subunits. Two major radioactive peptides were resolved by high-performance liquid chromatography from tryptic digests of MF1 which had been inactivated with 8-N3-FSB[3H]A at pH 8.0 in the dark. Sequence analysis revealed that one contained Tyr-beta 368 and the other contained His-beta 427 which were labeled in the ratio of 18:15. Sequence analysis of radioactive tryptic peptides isolated from digests of irradiated MF1 derivatized with 8-N3-FSB[3H]A showed that photolysis induced cross-linking of His-427 to Tyr-345 within the same beta subunit in high yield. When MF1 derivatized with 8-N3-FSB[3H]A was irradiated in the presence of beta-mercaptoethanol, alpha-beta cross-links were eliminated, whereas those between His-beta 427 and Tyr-beta 345 were unaffected. Analysis of radioactive peptides in tryptic digests of MF1 derivatized with 8-N3-FSB[3H]A and then irradiated in the presence or absence of beta-mercaptoethanol showed that the nitrene generated from reagent attached to Tyr-beta 368 participates in formation of alpha-beta cross-links in the absence of beta-mercaptoethanol. Therefore, the nitrene generated from reagent tethered to His-beta 427 is shielded from solvent and reacts with the side chain of Tyr-beta 345. In contrast, the nitrene generated from reagent attached to Tyr-beta 368 is exposed to solvent, but in the absence of scavengers reacts with side chains present in the alpha subunit. Irradiation of MF1, partially inactivated with 8-N3-FSBA, led to loss of residual ATPase activity without affecting residual ITPase activity. The amount of photoinactivation was greater when partial dark inactivation was performed at pH 6.9, where modification of His-beta 427 predominates, than when performed at pH 8.0, where modification of Tyr-beta 368 predominates. This suggests that cross-linking of His-beta 427 to Tyr-beta 345, and not cross-linking of alpha and beta subunits, is responsible for the augmented inactivation induced by irradiation.

Adenosine↗
PubMed1992

Use of the ASI titanium stent in the management of bladder outflow obstruction due to benign prostatic hyperplasia.

An expandable titanium intraprostatic stent was inserted into 30 patients with infravesical obstruction due to benign prostatic hyperplasia (BPH). All of the men were considered unsuitable for transurethral resection of the prostate as a result of comorbid conditions. In 25 patients effective micturition was reestablished with this technique. In 21 of these men, who have been followed for longer than 1 year, the mean maximum flow rate at 1 year was 10.8 ml. per second and the mean residual urine was 56 ml. Although urinary tract infections occurred subsequent to stent insertion in 10 individuals, these resolved after appropriate antibiotic treatment and no stents have had to be removed for this reason. Followup cystoscopy or examination by electron microscopy of those stents that have been removed has shown partial epithelialization of the stent surface in a proportion of patients, and a minor degree of incrustation occurred in 1 case. We conclude that an expandable intraprostatic titanium stent is an acceptable alternative to transurethral resection of the prostate or long-term catheterization in this particular group of high risk patients.

Aged↗
PubMed1992

Post-lumbar puncture headaches: experience in 501 consecutive procedures.

To ascertain the frequency and risk factors for post-lumbar puncture headache, we studied all adults who had an ambulatory lumbar puncture (LP) in a 1-year period. Patients filled out a questionnaire detailing their headache experience on the day of, and the 6 days following, LP. Those who did not return the questionnaire were telephoned. We systematically collected and analyzed many items, including the lumbar puncturist's experience, the degree of difficulty of the LP, CSF findings, final diagnosis, and the patient's demographic characteristics. Patients reporting headache before LP were more likely to report post-LP headaches. In addition to this, younger female patients with a lower body mass index have the highest risk of developing post-LP headaches. CSF opening pressure, cells, and protein, patient's position during LP, the duration of recumbency following LP, and the amount of CSF removed at the time of LP did not influence the occurrence of headache.

Adolescent↗
PubMed1992

Medical students' knowledge of and exposure to cleft palate.

To compare the knowledge and experience of medical students in 1989 with that of those surveyed in 1973, a questionnaire about the various aspects of cleft palate was completed by 209 medical students from West Virginia University and the Louisiana State University Medical Center at Shreveport and New Orleans. Results revealed that 1989 students were more familiar with the embryology of cleft palate, racial and gender differences, and intellectual and psychologic issues (p less than .05). In contrast, the 1973 students were more able to define cleft palate, submucous cleft palate, and pharyngeal flap. There was no difference between the two groups of students in the amount of clinical exposure to cleft palate. These findings support the need for greater emphasis on cleft palate at the pre- and postdoctoral levels, as well as within continuing education programs. As part of current programs, the standard of practice of multidisciplinary team management for an individual with cleft palate should be underscored.

Cleft Palate↗
PubMed1992

[Vocals in silence and noise. A simple test of resistance of intelligibility in noisy environment].

We have all noticed that there was no coincidence between the conventional audiometric tests--tonal, vocal, Metz tests--and the degree of impairment of understandability in noisy environments that the patients report. Some of them handle this problem better than these conventional tests suggest, others less well. The aim of this study is to take account of this dominating functional complaint: impairment in noisy conditions, and to assess it in order to follow up its evolution after medical, surgical and prosthetic treatments. The aim of the authors has been to describe an easy examination to be implemented in any ENT surgery fitted with a free-field vocal testing equipment. The results show that this test cas differentiate between "noise-resistant" subjects and those that do not "resist" well. The discussion defines the limitations of this test, which are due to its deliberate simplicity, and the caution required for its psychoacoustic and physiological interpretation. The conclusion confirms its merits, since it can discriminate and help choose more accurate tests--temporal tests, frequency selectiveness charts, twin-ear tests, cognitive AEP.

Audiometry, Speech↗
PubMed1991

Sensitization in vitro of human peripheral blood mononuclear cells to phenolic glycolipid 1 of Mycobacterium leprae in liposomes.

Study of primary immune responses in leprosy has been limited, since disease becomes manifest long after infection or is not detectable. To study primary immune responses, we immunized in vitro human peripheral blood mononuclear cells from unexposed individuals using phenolic glycolipid 1 (PGL-1), an important water-insoluble antigenic constituent of Mycobacterium leprae. PGL-1, encapsulated in liposomes, induced lymphoproliferation or, less frequently, suppression of lymphoproliferation in 11-day lymphocyte cultures. The primary lymphocyte responses resembled those elicited with keyhole limpet hemocyanin (KLH). HLA-DR2 expression, associated with tuberculoid leprosy, did not influence the outcome of in vitro sensitization. The association of HLA-DR2 and tuberculoid leprosy is not explained by differential ability to generate primary lymphoproliferative responses to PGL-1 or KLH. We have extended in vitro sensitization methodology to include a water-insoluble antigen in antigen-bearing liposomes. This methodology is potentially useful for studies of immunogenetics and immunopathology, and for vaccine research.

Antigens, Bacterial↗
PubMed1991

Myocardial ischemia during daily activities: the importance of increased myocardial oxygen demand.

The role of increased myocardial oxygen demand in the pathophysiology of myocardial ischemia occurring during daily activities was evaluated in 50 patients with coronary artery disease and exercise-induced ST segment depression. Each patient underwent ambulatory electrocardiographic (ECG) monitoring for ST segment shifts during normal daily activities and symptom-limited bicycle exercise testing with continuous ECG monitoring. All 50 patients had ST depression greater than or equal to 0.1 mV during exercise. A total of 241 episodes of ST depression were noted in the ambulatory setting in 31 patients; only 6% of these were accompanied by angina pectoris. Significant (0.1 mV) ST depression during ambulatory monitoring was preceded by a mean increase in heart rate of 27 +/- 12 beats/min. Patients with ischemia during daily activities developed ST depression earlier during exercise (7.9 +/- 4.4 vs. 14.2 +/- 6.4 min, p less than 0.001) and tended to have significant ECG changes at a lower exercise heart rate and rate-pressure product than did those without ST depression during ambulatory monitoring. In the 31 patients with ischemia during daily activities, the mean heart rate associated with ST depression in the ambulatory setting was closely correlated with the heart rate precipitating ECG changes during exercise testing (r = 0.74, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗
PubMed1991

Induction of chronic human immunodeficiency virus infection is blocked in vitro by a methylphosphonate oligodeoxynucleoside targeted to a U3 enhancer element.

Oligodeoxynucleosides with internucleoside methylphosphonate linkages complementary to regions within U3 of human immunodeficiency virus type 1 were evaluated for their ability to block phorbol myristate acetate upregulation of virus in chronically infected promonocytic and T-lymphoblastoid cell lines. One such oligomer, targeted to an NF-kappa B enhancer element, inhibited phorbol myristate acetate induction of viral replication and tat-mediated trans activation of the human immunodeficiency virus long terminal repeat. The effect of this construct is contrasted with classical antisense methylphosphonate-derivatized oligomers complementary to initiation codon and splice acceptor sites of human immunodeficiency virus structural and regulatory genes. Its activity suggests a novel application of the modified oligonucleotide strategy in the blockade of viral induction from latently infected cells.

Antiviral Agents↗
PubMed1991

Dental students' knowledge of an exposure to cleft palate.

A questionnaire was administered to 108 dental students from West Virginia University to assess their knowledge of cleft palate. Results revealed areas of deficiency in basic knowledge and exposure to clefting. When these data were compared to those from an earlier study (Lass et al., 1973) differences were found of varying type. A comparison between dental and medical students revealed that the basic knowledge of cleft palate and associated problems were not different between the two groups. However, the dental students had done more reading than the medical students and had the topic of cleft palate included in their coursework.

Cleft Palate↗
PubMed1991

The development of ethical thought in long-term care.

1. Pervasive medical technology influences treatment decisions in long-term care. Clinical decision-making is enhanced by the development of an ethical thought process among staff. 2. Disagreements among staff about the appropriateness of clinical decisions can lower staff morale and negatively affect the work environment. 3. Staff education about ethical principles and how they influence decision-making helps to define the patient's rights and the caregiver's responsibilities. 4. The use of staff experiences in teaching ethical principles is successful in educating all levels of staff about everyday ethics in long-term care.

Attitude of Health Personnel↗
PubMed1991

Report on seminar: 'designing care'.

The seminar was held under the auspices of the National Demonstration Project, which is a combined effort of the Juran Institute and the Harvard Community Health Plan (HCHP). About 60 delegates attended the conference. Most were from the United States, the rest were from Canada, the Netherlands, the United Kingdom and Australia. The seminar was aimed at introducing those attending to the topic of clinical algorithms. The algorithms were presented as part of a total quality management process concerned with clinical decisions. Algorithms are designed as a pattern, or a map, of a clinical process. It is the aim of an algorithm to ensure stability in a clinical process and to enhance the quality of care given by the process. The seminar was a combination of general sessions and workshop sessions. The general sessions were managed by presenters who had considerable experience in the development of algorithms, and the same presenters then chaired the separate workshop sessions on a group basis. The workshop sessions concentrated on the simulation of algorithm development at the institutions of the attendees.

Algorithms↗
PubMed1991

Personality and socialization correlates of vicarious emotional responding.

The relations of personality and family characteristics to adults' negative vicarious emotional responses to sympathy and distress films were examined. Ss reported more sympathy and less personal distress and exhibited less skin conductance as well as heart rate deceleration when viewing a sympathy-evoking film. Dispositional emotional intensity and fantasy empathy were associated with greater self-reported emotional responding and higher skin conductance. Dispositional perspective taking and personal distress were positively and negatively correlated, respectively, with reported vicarious responding to the sympathy film when Ss were administered instructions to imagine the emotions of those in the films. Family cohesiveness was associated with reported sympathy and sadness in reaction to the sympathy film, whereas the expression of negative subordinate and positive emotional states in the home of origin was associated with women's reported responsivity.

Adult↗
PubMed1990

Effect of diarrhoeal disease control on infant and childhood mortality in Egypt. Report from the National Control of Diarrheal Diseases Project.

The effect of the National Control of Diarrheal Diseases Project, started in 1983, on infant and childhood mortality in Egypt was assessed by means of national civil registration data, nationwide cluster sample surveys of households, and local area studies. Packets of oral rehydration salts are now widely accessible; oral rehydration therapy is used correctly in most episodes of diarrhoea; most mothers continue to feed infants and children during the child's illness; and most physicians prescribe oral rehydration therapy. These changes in the management of acute diarrhoea are associated with a sharp decrease in mortality from diarrhoea, while death from other causes remains nearly constant.

Cause of Death↗
PubMed1990

Adverse drug effects attributed to phenylpropanolamine: a review of 142 case reports.

Phenylpropanolamine (PPA) is contained in about 106 products, over half of which are available over-the-counter (OTC). Most are cough/cold remedies; nine are OTC diet aids. More than nine million Americans were using OTC diet aids in 1981, making PPA the fifth most used drug in the United States, responsible for over $200 million in revenues. The safety of PPA remains controversial. Although most controlled studies indicate minimal pressor effects with recommended doses, adverse drug reactions (ADRs) continue to be documented. Since 1965, 142 ADRs have been reported in 85 studies, 69% of these in North America. Many such cases may go unrecognized. About two thirds of all ADRs occurred in females and in patients under 30. Of ADRs attributed to legitimately sold PPA products, 85% occurred after consumption of OTC products versus only 15% after prescription drugs. The PPA product often contained combination ingredients, or PPA was consumed along with additional drugs. An overdose of PPA was taken in about a third of the cases. After ingestion of non-overdose amounts, 82% of the ADRs were severe. The most frequent side effects involved symptoms compatible with acute hypertension, with severe headache the most common complaint. Twenty-four intracranial hemorrhages, eight seizures, and eight deaths (most due to stroke) were associated with PPA ingestion. We have summarized these data in an effort to alert clinicians to the prevalence of usage of PPA products and the potential for adverse effects. In patients who present with elevated blood pressure or signs of acute hypertension, especially hypertensive encephalopathy of undetermined origin, we recommend inquiry about recent ingestion of PPA-containing diet aids and cough/cold products and suggest having such patients remain upright rather than supine.

Drug Combinations↗
PubMed1990

Pituitary-adrenal and adrenomedullary responses to noise in awake dogs.

Experiments characterized the dynamics of the pituitary and adrenocortical response to noise in awake dogs to determine if a dissociation exists between changes in plasma bioactive (bio) adrenocorticotropic hormone (ACTH) and immunoreactive (ir) ACTH. In addition, experiments determined the temporal relationship between cardiovascular, adrenomedullary, and adrenocortical responses induced by the acute presentation of noise. Trained dogs were prepared chronically with adrenal venous and femoral arterial cannulas. Experiments were done 48-96 h postsurgery and consisted of presentation of noise (75 dB; 0.25-8 kHz) for 3 min (n = 6) or of blood sampling alone (n = 5). In response to noise, mean arterial pressure and heart rate increased at 30 s and returned to base line at 4 min. Adrenal secretion of epinephrine and norepinephrine increased at 1 min and remained elevated until 4 min. Adrenal blood flow increased from 2 to 4 min as the result of a parallel increase in adrenal vascular conductance. Plasma bioACTH increased from 6 to 15 min in parallel with that of plasma irACTH. Before noise, the ratio of bioACTH to irACTH was 0.2-0.3, but the absolute change in bioACTH and irACTH after noise was not different. The increase in plasma ACTH occurred concomitant with or preceded an increase in cortisol secretion. Blood sampling alone caused no change in any variable. These data show that unexpected noise evokes a sequence of responses with rapid onset that includes tachycardia, hypertension, and increases in adrenomedullary secretion and adrenal vascular conductance.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Medulla↗
PubMed1990

Sensorineural hearing loss: a reversible effect of valproic acid.

We report 2 patients over the age of 70 who, while on valproate (VPA) for complex partial seizures, developed sensorineural hearing loss. Following discontinuation of VPA for nonaudiologic reasons, the patients reported improved hearing which was confirmed by audiometry. These findings represent VPA-induced sensorineural hearing loss, possibly in preexisting presbycusis.

Aged↗