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H E Smith

Publications and source records attributed to H E Smith.

At least 55 records · Page 3Linked to original sources
PubMed1995

Tissue-specific pharmacology of testosterone and 5 alpha-dihydrotestosterone analogues: characterization of a novel canine liver androgen-binding protein.

The mechanism by which the hormones 5 alpha-dihydrotestosterone and testosterone differentially regulate such diverse functions as development of male internal and external genitalia and maintenance of prostatic growth via a single androgen receptor (AR) is not well understood. To search for potential AR isoforms, an extensive pharmacological survey of the binding of [3H]mibolerone (7 alpha,17 alpha-[3H]dimethyl-19-nortestosterone) in dog prostate, adrenal gland, testis, liver, kidney, brain, muscle, and spleen cytosolic extracts was carried out. The antagonist androst-4-en-3,17-dione (ATD), as well as a series of unsaturated analogues of testosterone, exhibited marked tissue specificity for binding to mibolerone-binding proteins (MBPs), with ATD having a 10-fold higher affinity for the MBPs present in liver than for those in prostate and testis. The difference in affinity was not due to tissue-specific metabolism of ATD. Competition binding profiles for ATD with mixtures of prostate and liver extracts were consistent with two distinct populations of binding sites. Both wild-type human AR-B and the recently discovered human AR-A isoform were expressed in COS cells and were found to exhibit pharmacology similar to that of the prostatic MBPs in dogs. Analogues of ATD or testosterone could prove to be useful probes for delineating the differential effects of 5 alpha-dihydrotestosterone and testosterone on the biological actions of the AR and related proteins.

Androgen-Binding Protein↗
PubMed1995

Use of Multiscreen plates for the preparation of bacterial DNA suitable for PCR.

A rapid and inexpensive method for isolating bacterial DNA for use in PCR is described. The method is based on the guanidinium thiocyanate (GuSCN)-lysis method of Boom et al. (J. Clin. Microbiol. 28:495-503, 1990) and enables a multiple of 96 samples to be prepared in only one hour. We use Multiscreen plates and a vacuum manifold from Millipore. Clinical samples are lysed and washed in the wells of a Multiscreen plate, and DNA is eluted in a standard microplate. Purified DNA was recovered with high yields (over 25%). The method allows multichannel or robotic pipetting for both the sample preparation as well as for the PCR step. The method has been applied successfully to detect pathogenic Streptococcus suis type 2 in nasal and tonsil swab specimens of pigs.

Animals↗
PubMed1994

Binding of 5H-dibenzo[b,e][1,4]diazepine and chiral 5H-dibenzo[a,d]cycloheptene analogues of clozapine to dopamine and serotonin receptors.

5H-Dibenzo[b,e][1,4]diazepine, dibenz[b,f]oxepin, and 5H-dibenzo[a,d]cycloheptene analogues of clozapine [8-chloro-11-(4-methylpiperazino)-5H- dibenzo[b,e][1,4]diazepine] were evaluated for their binding affinity to dopamine D-1, D-2, and D-4 and serotonin S-2A (5-HT2A), S-2C (5-HT2C) and S-3 (5-HT3) receptors. The diazepine analogues display selective binding to the dopamine D-4 and serotonin S-2A receptors similar to that of clozapine, but none has a dopamine D-4 selectivity (Ki for the dopamine D-2A receptor/Ki for the dopamine D-4 receptor) greater than that of clozapine. All of the oxepin analogues also show substantial binding to the dopamine D-4 and serotonin S-2A receptors with 10-(4-methylpiperazino)dibenz[b,f]oxepin having a dopamine D-4 selectivity greater than that of clozapine. Some of the 5H-dibenzo-[a,d]cycloheptene analogues also show strong binding to both the dopamine D-4 and serotonin S-2A receptors, 5-methyl-10-(4-methylpiperazino)-5H-dibenzo[a,d]cycloheptene having a dopamine D-4 selectivity of 7.8 as compared to 10 for clozapine but a serotonin S-2A selectivity (Ki for the dopamine D-2 receptor/Ki for the serotonin S-2A receptor) of 2.0 as compared to 28 for clozapine. The serotonin S-2A selectivity of 2-chloro-10-(4-methylpiperazino)-5H-dibenzo[a,d]-cycloheptene++ + is 200. As an extension of these studies, chiral 5-substitute 10-(1,2,3,6-tetrahydro-1-methyl-4-pyridinyl)-5H-dibenzo[a,d]cyclohept ene analogues show a substantial enantiospecificity toward dopamine and serotonin receptor subtypes, (R)-(-)-5-methyl compound having a 2-fold higher dopamine D-4 selectivity than its (S)-(+) enantiomer as the result of enhanced binding to the dopamine D-4 receptor rather than diminished binding to the dopamine D-2 receptor. (pRa,pSb)-(+)-5-(2-Propylidene)-10-(1,2,3,6-tetrahydro-1-met hyl- 4-pyridinyl)-5H-dibenzo[a,d]cycloheptene is 17 times more active in binding to the dopamine D-4 receptor than is its pSa,pRb enantiomer while being only 1.5 times more active in binding to the dopamine D-2 receptor.

Animals↗
PubMed1994

Recombinant activated factor VII (rFVIIa) therapy for intracranial hemorrhage in hemophilia A patients with inhibitors.

We report the use of recombinant VIIa (rFVIIa) in the treatment of five ICHs in two factor VIII-deficient patients with inhibitors. In four of five ICHs, rFVIIa was the only factor replacement used at doses of 60-135 micrograms/kg every 2-4 hr for 12-14 days. Hemostasis at the primary site of bleeding was achieved in all cases, and all patients survived with no permanent neurologic deficits. However, the patient who received the highest dose of rFVIIa during the first 4 days of therapy developed clinical symptoms consistent with a cerebral vascular accident of the brainstem characterized by acute onset of truncal ataxia and upward-gaze nystagmus on day 8 of rFVIIa therapy. While receiving rFVIIa therapy for treatment of these five ICHs, four treatment courses were complicated by bleeding at sites other than the primary site, including two episodes of localized oozing at central line insertion sites, two episodes of hemarthrosis, and two episodes of epistaxis. Antifibrinolytic therapy with tranexamic acid was effective in two of these episodes. Laboratory evaluation revealed shortening of the PT, variable shortening without normalization of the APTT, peak factor VII activity levels 7-30-fold higher than normal baseline values, and normal antithrombin III (ATIII) and alpha 2-antiplasmin levels. In four of five ICHs, there was a 20-40% decrease in fibrinogen levels from baseline. The decrease in fibrinogen was accompanied by an increase in fibrin degradation products in 3/5 episodes and a 15-35% decrease in plasminogen activity levels in 2/5 episodes. Tissue factor pathway inhibitor (TFPI) levels remained stable and in the normal range. Although rFVIIa is an effective new therapy for the treatment of ICH in hemophilia patients with inhibitors, its optimal use with respect to safety and efficacy requires further clinical study.

Cerebral Hemorrhage↗
PubMed1994

Haematological and lymphocyte subset analyses in sheep inoculated with bovine immunodeficiency-like virus.

Bovine immunodeficiency-like virus (BIV) was passaged in vivo by intraperitoneal transfusion of ovine whole blood. Prior to transfusion, the recipient sheep were given sodium thioglycolate intraperitoneally to induce mild non-suppurative inflammation. The anti-BIV antibody response, haematology, and peripheral blood lymphocyte subsets (B, gamma delta, CD2+, CD4+ and CD8+) of recipient sheep were assessed for one year following transfusion. Passaging was successful since serum anti-BIV antibody responses were detected in 5 of the 6 recipient sheep; 1 of the 5 remained seropositive throughout the study. Lentivirus was not isolated from the recipient sheep, but provirus was detected by the polymerase chain reaction in DNA from peripheral blood leukocytes in 3 of the 5 sheep that seroconverted. In the BIV-inoculated sheep, neutrophils and eosinophils were significantly increased (p < or = 0.05) at 3 months and between 6 and 8 months postinoculation, respectively. B, CD2+ and CD4+ cells and the CD4+/CD8+ ratios were significantly increased (p < or = 0.05) 2 months postinoculation. Mild, transient haematological changes occurred in BIV-exposed sheep, but illness was not detected in the year.

Animals↗
PubMed1994

Cell-mediated and humoral immunity in sheep exposed to bovine immunodeficiency-like virus.

Six sheep were transfused intraperitoneally with whole blood from two sheep chronically infected with the bovine immunodeficiency-like virus (BIV). Five sheep were transfused intraperitoneally (i.p.) with normal ovine whole blood and served as controls. Five of six BIV-inoculated sheep seroconverted; four were transiently seropositive while one remained seropositive for the duration of the experiment. Tests for nonspecific lymphocyte reactivity to mitogens were performed monthly for one year. At approximately 10 months postinoculation, all sheep were immunized with chicken ovalbumin, canine red blood cells, and tuberculin. There were no significant associations between BIV exposure and deficits in antibody production to chicken ovalbumin and canine red blood cells; nonspecific lymphoproliferative responses to concanavalin-A, lipopolysaccharide, and pokeweed mitogen; specific lymphoproliferative responses to ovalbumin and tuberculin purified protein derivative; or cutaneous delayed type hypersensitivity to tuberculin purified protein derivative. Exposure to BIV did not alter the humoral or cell mediated immune responses of sheep in the first year of exposure.

Animals↗
PubMed1994

Flow cytometric analysis of ovine peripheral blood lymphocytes.

Leukocyte suspensions were prepared from the peripheral blood of 12 sheep three times at two month intervals beginning at 12 months of age. Monoclonal antibodies and flow cytometric analysis were used to characterize the cells. There were no significant differences over time therefore the data from the three time intervals were pooled. The mean percentages and ranges (minimum to maximum) of the major lymphocyte subtypes were: B-cells (29.6%, 11-50), gamma delta T-cells (36.6%, 22-68), CD4+ T-cells (14.1%, 8-22) and CD8+ T-cells (12.0%, 4-22). Lymphocyte subtype percentages appeared less variable within than between individuals. Two populations of B-cells were noted; one population had more cytoplasm and light scatter characteristics similar to monocytes while a second population of B-cells was more typical of small lymphocytes. The nature of the large B-cells requires further study.

Animals↗
PubMed1994

A serological survey for bovine immunodeficiency-like virus in Ontario dairy cattle and associations between test results, production records and management practices.

A chemiluminescence Western blot analysis (WBA) for detecting antibovine immunodeficiency-like virus (BIV) antibodies, had good repeatability. The test was subsequently applied to a bank of serum samples from 928 adult cows from 265 herds in Ontario; the number of cows sampled within each herd ranged from 1 to 13. The overall prevalence of anti-BIV antibodies among cows was 5.5% with a 95% confidence interval of 4.2% to 7.2%. In contrast, 18.1% of herds had at least one reactor among cows tested, resulting in a herd-prevalence confidence interval of 13.8% to 23.4%. These estimates of prevalence were in the same range as previous reports from the US and Europe. Bovine immunodeficiency-like virus may have a worldwide distribution. Unfortunately, BIV test sensitivity and specificity are difficult to estimate because virus isolation is inefficient. Therefore, the apparent prevalences could not be adjusted for test sensitivity and specificity, to estimate the true prevalence of infection. The serum samples had previously been tested for antibodies to bovine leukemia virus (BLV). There were no significant associations between BIV and BLV test results. Least squares regression was used to investigate potential associations between BIV test results and selected production indices.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Husbandry↗
PubMed1993

Preventive practice among primary care physicians in British Columbia: relation to recommendations of the Canadian Task Force on the Periodic Health Examination.

OBJECTIVES: To compare the current practice of preventive medicine in British Columbia with the recommendations of the Canadian Task Force on the Periodic Health Examination. Four common, preventable forms of cancer (cervical, breast, lung and colorectal) were used as sentinel conditions. DESIGN: Random sample mailed survey. SETTING: Private primary care practices in British Columbia. PARTICIPANTS: A sample of 300 primary care physicians in 1991; of 285 eligible physicians 185 (65%) responded. OUTCOME MEASURE: Compliance with preventive practices recommended by the task force. RESULTS: Preventive practice complied with the task force's recommendations for breast examinations, mammography, cervical smears and initial counselling against smoking; over 90% of the physicians performed these manoeuvres in all or most cases. However, less than half performed two recommended manoeuvres for all or most patients who smoke: advice to follow a diet high in beta-carotene (reported by 10%) and scheduling of follow-up visits to reinforce antismoking counselling (by 46%). Most of the physicians stated that they perform preventive manoeuvres in the context of an annual general physical examination rather than integrating them into routine patient care. CONCLUSIONS: The task force's carefully constructed recommendations are incompletely followed. Overall, there appears to be a high level of compliance with traditional and recommended manoeuvres but also widespread persistence in performing traditional manoeuvres no longer recommended and failure to adopt new recommendations.

Breast Neoplasms↗
PubMed1993

Absolute configuration of (+)-cis-2,3-dihydro-2-[(methylamino)methyl]-1- [4-(trifluoromethyl)phenoxy]-1H-indene hydrochloride, a chiral serotonin uptake inhibitor.

The absolute configuration of (+)-cis-2,3-dihydro-2[(methylamino)methyl]- 1-[4-(trifluoromethyl)phenoxy]-1H-indene hydrochloride, the more active enantiomer of a new serotonin inhibitor, was established as 1S,2S. This assignment was based on the application of the benzene sector and chirality rules to the interpretation of the inhibitor's circular dichroism spectrum and the spectra of other related chiral 1-substituted 2,3-dihydro-1H-indenes.

Circular Dichroism↗
PubMed1993

Discrimination between virulent and nonvirulent Streptococcus suis type 2 strains by enzyme-linked immunosorbent assay.

Discrimination between virulent and nonvirulent strains of Streptococcus suis type 2 will allow proper diagnosis of diseased pigs and the identification of carrier pigs. To discriminate between virulent and nonvirulent strains, we developed two double antibody sandwich (DAS) enzyme-linked immunosorbent assays (ELISA) using specific monoclonal antibodies directed against two virulence markers of S. suis type 2. One mAb was directed against the 136-kilodalton (kDa) cell-wall-associated protein, designated muramidase-released-protein (MRP). The other mAb was directed against a 110-kDa extracellular protein, provisionally called extracellular factor (EF). We examined 179 strains of S. suis serotype 2, 22 strains of S. suis serotypes 1 to 22, 22 other streptococci, 20 other bacterial strains, and one yeast. The ELISA results were almost identical with western blot analysis of these strains. Visual readings of the two DAS-ELISAs were enough to discriminate accurately between the three phenotypes of S. suis type 2. We concluded that the two DAS-ELISAs are reliable, rapid, and simple assays to identify virulent strains of S. suis type 2.

Animals↗
PubMed1993

Genetic evidence for transcriptional activation by the yeast IME1 gene product.

IME1 is required in yeast for meiosis and for expression of IME2 and other early meiotic genes. IME1 is a 360-amino acid polypeptide with central and C-terminal tyrosine-rich regions. We report here that a fusion protein composed of the lexA DNA-binding domain and IME1 activates transcription in vivo of a reporter gene containing upstream lexA binding sites. Activation by the fusion protein shares several features with natural IME1 activity: both are dependent on the RIM11 gene product; both are impaired by the same ime1 missense mutations; both are restored by intragenic suppressors. The central tyrosine-rich region is sufficient to activate transcription when fused to lexA. Deletion of this putative activation domain results in a defective IME1 derivative. Function of the deletion derivative is restored by fusion to the acidic Herpesvirus VP16 activation domain. The C-terminal tyrosine-rich region is dispensable for transcriptional activation; rather it renders activation dependent upon starvation and RIM11. Immunofluorescence studies indicate that an IME1-lacZ fusion protein is concentrated in the nucleus. These observations are consistent with a model in which IME1 normally stimulates IME2 expression by providing a transcriptional activation domain at the IME2 5' regulatory region.

Bacterial Proteins↗
PubMed1993

Repeats in an extracellular protein of weakly pathogenic strains of Streptococcus suis type 2 are absent in pathogenic strains.

Streptococcus suis type 2 strains that are pathogenic for pigs produce a 110-kDa extracellular protein factor (EF). Nonpathogenic and weakly pathogenic strains do not produce EF or produce a protein (EF*) that is immunologically related to EF. To study the pathogenesis of S. suis type 2 in pigs and to develop tools and methods for the control of S. suis type 2 infections, we cloned and characterized the genes encoding EF and various EF* proteins. Analysis of the deduced amino acid sequences showed that the first 833 amino acids at the N terminus of the EF and EF* proteins were nearly identical. The proteins differed, however, at their C termini. Unlike the 110-kDa EF protein, the EF* proteins contained several repeated units of 76 amino acids. The number and arrangement of the repeats in the EF* proteins varied. The data suggest that the gene encoding EF could have evolved from an epf* gene by a specific deletion event. The lack of repeated amino acid units in the EF protein may be related to virulence.

Amino Acid Sequence↗
PubMed1993

Serological evidence of bovine immunodeficiency-like virus infection in a sheep.

A six month-old sheep was entered into a control group in an experiment designed to study the effects of exposure to the bovine immunodeficiency-like virus (BIV). Anti-BIV antibodies were detected in the serum of this sheep prior to the start of the study; these antibodies persisted for 12 months at which time the animal was destroyed. The sheep was normal clinically and was grossly normal at postmortem examination. Blood from this sheep was inoculated into a recipient sheep which subsequently showed a transient anti-BIV antibody response beginning two months postinoculation. Sheep have been previously shown to produce anti-BIV antibodies after experimental inoculation with infected cell culture material or infected bovine blood and BIV infection was found in a sheep pastured with BIV-infected cattle. In the present case there was no contact with cattle; the source of the infection was not identified.

Animals↗
PubMed1993

Assessing the utilization of in-patient facilities in a Canadian pediatric hospital.

STUDY OBJECTIVE: To validate the pediatric appropriateness evaluation protocol (P-AEP) for use in the Canadian health care system and then to use it to assess the extent of inappropriate utilization in a Canadian tertiary care pediatric facility. METHOD: The P-AEP was applied to a 10% random sample of all general pediatric admissions during 1990 and to a sample of 547 subsequent days of care. The reliability of the P-AEP was assessed using a subsample of 72 admissions and 72 days of care. Validity was tested by comparing the P-AEP judgment on a sample of 50 admissions and 50 days of care with the subjective opinion of panels of three pediatric staff physicians. RESULTS: In the reliability test, there was a high level of agreement between the two independent observers applying the P-AEP. In validity testing, the physicians found a slightly lower rate of inappropriateness relative to the P-AEP, but the validity was good overall. In the main study, 136 of 477 admissions (29%) were found to be inappropriate. Factors associated with inappropriate admission included nonurgent or emergent admission, surgical (versus medical) cases, residence outside the Greater Vancouver area, and admission on Sundays or Mondays. Fifty-five percent of inappropriate admissions were judged necessary but premature, whereas 45% were judged medically unnecessary. Of 547 subsequent days of care, 121 (22%) were found to be medically inappropriate. Inappropriate days of care were associated with girls, Mondays, and patients older than 14 years of age. CONCLUSIONS: The P-AEP seems to be a valid and useful instrument for assessing the utilization of pediatric beds in a Canadian health care setting. Using the P-AEP made it possible to identify several service and policy developments which would help improve the efficiency of utilization at the hospital.

Adolescent↗
PubMed1992

Preparation of 17 alpha-iodoethynylandrosta- and 17 alpha-(2-iodoethenyl)androsta-4,6-dien-17 beta-ol-3-ones as active site-directed photoaffinity ligands for androgen-binding proteins.

Unsaturated analogues of androst-4-en-17 beta-ol-3-one, each with a 17 alpha-iodoethynyl or 17 alpha-(2-iodoethenyl) substituent, were prepared, and their relative binding affinities (RBAs) for androgen-binding protein (ABP) were compared with those of 5 alpha-androstan-17 beta-ol-3-one, androst-4-en-17 beta-ol-3-one, androsta-4,6-dien-17 beta-ol-3-one, and androsta-1,4,6-trien-17 beta-ol-3-one. These binding studies indicate that the iodine[125I] analogues of 17 alpha-iodoethynyl and 17 alpha-[(E)-2-iodoethenyl] derivatives of androsta-4,6-dien-17 beta-ol-3-one and androsta-1,4,6-trien-17 beta-ol-3-one will have RBAs at least twice as great as that of 5 alpha-androstan-17 beta-ol-3-one. They can be prepared from 17 alpha-ethynylandrosta-4-en-17 beta-ol-3-one, the final synthetic step using N-[125I]iodosuccinimide, and are potential radioiodinated, active site-directed photoaffinity ligands for ABP and testosterone-binding globulin.

Affinity Labels↗