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Biomedical subjects

B Smith

Publications and source records attributed to B Smith.

At least 289 records · Page 16Linked to original sources
PubMed1991

Root substance removal by scaling and root planing.

The amount of root substance removed by scaling and root planing is largely unknown. The present study evaluated in vitro the root substance loss caused by a defined number of working strokes at known forces. Forty extracted teeth with loss of connective tissue attachment into the middle third of the roots were washed and embedded in plaster, leaving one entire corono-apical tooth aspect exposed. The teeth were reproducibly repositioned in a bench-vise, where a profilometer repeatedly measured root surface levels at the same location. In a standard area of the roots a total of 40 working strokes were applied. Low forces were used in 30 teeth and high forces in 10 teeth. The forces were recorded using a piezo-electric receiver built into the upper shank of the curet. Root substance loss was measured after 5, 10, 20, and 40 working strokes. The results showed that the mean low force used per working stroke across all 40 strokes was 3.04 Newtons for the low forces, and 8.48 Newtons for the high forces. Mean cumulative loss of root substance across 40 strokes was 148.7 microns at low forces, and 343.3 microns at high forces. The mean force per stroke increased slightly across the 40 strokes, while substance removal per stroke decreased. Substance removal per stroke during strokes 1 to 5 was 6.8 microns using low forces and 20.6 microns using high forces. During strokes 21 to 40 mean removal per stroke was 2.3 microns at low forces, and 5.6 microns at high forces. These results suggest that high forces remove more root substance, and loss per stroke becomes less with increasing numbers of strokes.

Dental Scaling↗
PubMed1991

Induction of differentiation of avian erythroblastosis virus-transformed erythroblasts by the protein kinase inhibitor H7: analysis of the transcription factor EF1.

The protein kinase inhibitor H7 [1-5(isoquinolinesulfonyl-2-methylpiperazine)] together with a temperature shift to 42 degrees C was found to reproducibly and efficiently induce differentiation of avian erythroblasts transformed with the avian erythroblastosis virus containing v-erbA and a temperature-sensitive v-erbB oncogene. Although a temperature shift to 42 degrees C without H7 results in some elevation of globin transcripts, much higher levels of transcripts accrue when cells are incubated at 42 degrees C with H7; under such conditions, 50-70% of the cells become benzidine positive. In order to investigate the mechanism by which the differentiation occurs, we have characterized and analyzed the levels of the erythroid transcription factor EF1, originally described as a factor binding to the beta H-globin promoter. Protein sequencing of EF1 shows that it is identical to the factor Eryf1. Using a peptide antibody and DNA-binding assays, we demonstrate that EF1 is present at high levels in the nucleus of undifferentiated HD3 cells, and, although there may be a small change when the cells are shifted to 42 degrees C, incubation of the cells with H7 at 42 degrees C does not result in a further elevation commensurate with the high levels of globin transcripts. It is concluded that v-erbA and v-erbB do not repress differentiation by limiting the levels of EF1.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1991

The patient with noncardiogenic pulmonary edema.

Based on the content of this article, the reader should be able to (1) identify the differences between cardiogenic and noncardiogenic pulmonary edema (NCPE); (2) identify the most common causes of airway obstruction leading to pulmonary edema; (3) state the mechanism of action for the development of NCPE following laryngospasm; (4) state the signs and symptoms of NCPE; (5) identify the treatment for NCPE; and (6) state three nursing actions that are indicated in the care of the patient with NCPE.

Adult↗
PubMed1990

Physical maps of 4p16.3, the area expected to contain the Huntington disease mutation.

The gene for Huntington disease, a neurodegenerative disorder with autosomal dominant inheritance, has been localized to the terminal portion of the short arm of human chromosome 4 (4p16.3) by linkage analysis. Since eventual isolation of the gene requires the application of high-resolution genetic analysis coupled with long-range DNA mapping and cloning techniques, we have constructed a physical map of the chromosomal region 4p16.3 using more than 20 independently derived probes. We have grouped these markers into three clusters which have been ordered and oriented by genetic and somatic cell genetic mapping information. The mapped region extends from D4S10 (G8) toward the telomere and covers minimally 5 Mb.

Chromosome Mapping↗
PubMed1990

Doppler echocardiographic measurement of pulmonary artery pressure from ductal Doppler velocities in the newborn.

The ductal flow velocities in 37 newborns (group 1: persistent pulmonary hypertension [n = 16], transient tachypnea [n = 3], other [n = 2]; group 2: respiratory distress syndrome [n = 16]) were prospectively evaluated by Doppler ultrasound for the purpose of deriving systolic pulmonary artery pressures. Maximal tricuspid regurgitant Doppler velocity in 21 of these patients was used to validate the pulmonary artery pressures derived from ductal flow velocities. There was a significant linear correlation between tricuspid regurgitant Doppler velocity and pulmonary artery systolic pressure derived from ductal Doppler velocities in patients with unidirectional (pure left to right or pure right to left) ductal shunting (p less than 0.001, r = 0.95, SEE 8) and in those with bidirectional shunting (p less than 0.001, r = 0.95, SEE 4.5). Systolic pulmonary artery pressure in group 1 (67 +/- 13 mm Hg) was significantly higher than that in group 2 (39 +/- 10 mm Hg) (p less than 0.001). In those with bidirectional shunting, duration of right to left shunting less than 60% of systole was found when pulmonary artery pressure was systemic or less, whereas duration greater than or equal to 60% was associated with suprasystemic pulmonary artery pressures. Serial changes in pulmonary artery systolic pressure, reflected by changes in ductal Doppler velocities, correlated with clinical status in persistent pulmonary hypertension of the newborn. Persistently suprasystemic pulmonary artery pressure was associated with death in five group 1 patients. It is concluded that ductal Doppler velocities can be reliably utilized to monitor the course of pulmonary artery systolic pressures in newborns.

Blood Flow Velocity↗
PubMed1990

Gamete intra-fallopian transfer in non-endometriotic pelvic adhesions.

This report presents our experience with gamete intra-Fallopian transfer (GIFT) in cases with non-endometriotic pelvic adhesions. Two-hundred-and-eight GIFT attempts, where pelvic adhesions were identified laparoscopically in patients with no previous history of endometriosis, were subdivided into two groups: (i) post-surgical (n = 134) and (ii) non-surgical (n = 74). The extent of the adhesions was further classified according to the American Fertility Society (AFS) classification system. The overall clinical pregnancy rate was 39.4% (82 out of 208 attempts). There was no significant difference in the clinical pregnancy rate per attempt between the surgical (38.8%) and the non-surgical (40.5%) groups. A gradual, but not significant decline in the pregnancy rate was noticed from adhesion Stages I to III, but Stage IV had a significantly lower pregnancy rate (22.7%) than Stage I (47.4%). The intra-uterine pregnancy rate was observed to be higher, but not significantly, in the non-surgical (37.8%) than in the surgical (29.1%) cases. The overall ectopic pregnancy rate was 7.2% per attempt and 18.3% per clinical pregnancy. In the post-surgical group, the ectopic pregnancy rate per pregnancy was 3.5 times that in the non-surgical (23.2% versus 6.5%, respectively), and it was significantly higher in Stage IV (40%; two out of five pregnancies) than in Stage I adhesions (11.1%; three out of 27 pregnancies). In cases with a history of tubal surgery, the ectopic pregnancy rate was 33.3% (10 out of 30 pregnancies). Our results indicate that GIFT can offer a successful treatment option for selected cases with non-endometriotic pelvic adhesions.

Adult↗
PubMed1990

Regional localization of polymorphic markers on chromosome 10 by physical and genetic mapping.

The human vimentin gene and a random DNA segment (D10S39) were mapped to the short arm of human chromosome 10 by linkage analysis. A panel of somatic cell hybrids and monosomy cell-lines, which divide chromosome 10 into seven regions, was used to localize 10 polymorphic markers on this chromosome. The physical map locations obtained correlate well with linkage maps of chromosome 10. Two markers which have been shown to be closely linked to the gene for multiple endocrine neoplasia type 2A map distal to a translocation breakpoint in band 10q11.2.

Animals↗
PubMed1990

Comparison of ofloxacin and ceftriaxone in the treatment of uncomplicated gonorrhea caused by penicillinase-producing and non-penicillinase-producing strains.

Eighty-nine patients with uncomplicated gonorrhea, including 31 patients (34.8%) infected with penicillinase-producing strains of Neisseria gonorrhoeae, were treated with oral ofloxacin (single 400-mg dose) or intramuscular ceftriaxone (250-mg dose). All 47 patients who received ofloxacin and 41 of 42 patients who received ceftriaxone were cured.

Adult↗
PubMed1990

Gender weighting of DSM-III-R personality disorder criteria.

This study explored the gender weighting of the diagnostic criteria for personality disorders. Gender weighting was defined in terms of how 33 female and 17 male nonclinicians ranked the diagnostic criteria along a male-female dimension. Although the a priori expectation was that antisocial would be the prototypically masculine personality disorder and histrionic the feminine, the subjects ranked criteria from the sadistic category as the most masculine and those from the dependent category as the most feminine. These results and the subjects' gender weighting of criteria for borderline, obsessive-compulsive, and self-defeating personality disorders are analyzed in detail.

Adolescent↗
PubMed1990

Reviewing the unicystic ameloblastoma: report of two cases.

Classification of ameloblastoma into solid, multicystic, unicystic, and peripheral types based on clinical appearance and effects has gained recent recognition. The unicystic ameloblastoma is a less encountered variant of the ameloblastoma. It appears more frequently in the second or third decade with no sexual or racial predilection. It is almost exclusively encountered asymptomatically in the posterior mandible. The following report of two cases discusses the pathophysiology, demographics, histology, and prognosis of the unicystic ameloblastoma.

Adult↗
PubMed1990

Carpal tunnel syndrome. Evaluation of a quantitative provocational diagnostic test.

A diagnostic test combining the sensitivity of the Semmes-Weinstein monofilament measurement and the specificity of the wrist flexion provocational test has been evaluated in a group of 21 patients (33 hands) with electrodiagnostically verified carpal tunnel syndrome and 30 asymptomatic hands (controls). Semmes-Weinstein monofilament testing consisted of several sensory threshold measurements obtained by the application of force-calibrated Semmes-Weinstein monofilaments to each digit in the hand with the wrist in neutral position. The quantitative provocational diagnostic test employed Semmes-Weinstein measurements obtained with the wrist both in the neutral and flexed positions. The sensitivity (82%) and specificity (86%) of the combined test were calculated. It was more sensitive and specific than the wrist flexion test alone and more specific than the Semmes-Weinstein sensibility test. The combined test is recommended as the most accurate and sensitive quantitative clinical test for median nerve compression evaluated by the authors to date.

Adult↗
PubMed1990

Behavior modification in pediatric hemodialysis.

This article reports the results of a behavior modification approach for managing disruptive and noncompliant behaviors in four male hemodialysis patients ranging in age from 10 to 16 years. Each patient demonstrated some improvement in either behavior or health status during the intervention and 76.7% of available token reinforcers were earned. The intervention was inexpensive and well-accepted by the patients, families, and staff. Guidelines for the planning, implementation, and evaluation of such interventions are presented.

Adolescent↗
PubMed1989

Yeast mutants conferring resistance to toxic effects of cloned human insulin-like growth factor I.

The production of extracellular human insulin-like growth factor I (IGF-I) in yeast is deleterious to the growth of the host organism. Mutants resistant to the toxic effects of IGF-I production were isolated. A subset of these mutants produced levels of IGF-I greater than the parent strain and were due to chromosomal recessive mutations at a single locus, hpx1. The overproduction of IGF-I was independent of the original promoter and vector expression system. The mutant strains also displayed enhanced extracellular production of other heterologous proteins.

Carboxypeptidases↗