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Biomedical subjects

D Shen

Publications and source records attributed to D Shen.

At least 127 records · Page 7Linked to original sources
PubMed1989

[Saliva phenobarbital concentration in epileptics].

The concentrations of phenobarbital were measured in saliva-serum pairs obtained simultaneously from 33 epileptics by RIA. The mean concentration of phenobarbital in saliva was 3.2 +/- 1.78 micrograms/ml, in serum was 11.75 +/- 7.4 micrograms/ml, the mean saliva-to-serum ratio for phenobarbital was 0.27 +/- 0.08. The results suggested that saliva concentration of phenobarbital was found to be correlated closely with the total serum level (R = 0.7922, P less than 0.01). The high correlation between saliva and serum concentrations supports the use of saliva measurement in epileptics. The simplicity and convenience of saliva collection and its noninvasiveness make it represent serum concentration of phenobarbital as an efficient monitoring method.

Adolescent↗
PubMed1988

Nasal pharmacodynamics of brompheniramine in perennial rhinitis.

This study evaluated the relationship between brompheniramine maleate and changes in nasal reactivity. Ten subjects with moderate-to-severe perennial rhinitis took brompheniramine for seven days using either a standard formulation or sustained-release preparation. Nasal aerodynamics and response to histamine were assessed at the end of the week. Despite varying doses of brompheniramine maleate (12 to 32 mg/d), there was no significant difference in nasal reactivity to histamine or in changes of nasal airflow, indicating that low doses of brompheniramine are highly effective in blocking histamine, receptors in the nasal mucosa.

Adolescent↗
PubMed1988

Levobunolol compared with timolol: a four-year study.

Fifty-one patients with raised intraocular pressure (IOP) were treated for up to four years with one of three ophthalmic solutions: 0.5% levobunolol, 1% levobunolol, or 0.5% timolol. The study was conducted as a double-masked, randomised trial in which medications were administered twice daily to both eyes. Levobunolol and timolol were equally effective in reducing overall mean IOP; reductions were greater than 8.8 mmHg in all three treatment groups. The study showed levobunolol to be as safe and effective as timolol in the long-term control of raised IOP.

Aged↗
PubMed1987

Specificity of sensitive assays of thyrotropin (TSH) used to screen for thyroid disease in hospitalized patients.

Thyrotropin (TSH) concentrations were measured in 1580 hospitalized patients and 109 normal persons. Using the mean +/- 3 SD limits of the log values for the controls (0.35-6.7 milli-int. units/L), the proportion of abnormal TSH results in the hospitalized patients was 17.2%. TSH was undetectable (less than 0.1 milli-int. unit/L) in 3.1% of patients, suggesting hyperthyroidism, and high (greater than 20 milli-int. units/L) in 1.6%, suggesting hypothyroidism. On follow-up of 329 patients, 62% with abnormal TSH (less than 0.35 or greater than 6.7 milli-int. units/L) and 38% with normal TSH concentrations, only 24% of those with undetectable TSH had thyroid disease: 36% of them were being treated with glucocorticoids and 40% had nonthyroidal illness (NTI). Although half the patients with TSH greater than 20 milli-int. units/L had thyroid disease, 45% of patients had high TSH values associated with NTI. TSH concentrations usually returned towards normal when patients' therapy with glucocorticoids was discontinued or they recovered from NTI. TSH test sensitivity appeared good when the mean +/- 3 SD limits of the reference population were used, i.e., no cases of hyper- or hypothyroidism, as identified by free thyroxin index (FT4I), were missed. However, TSH test specificity was inferior to that of the FT4I test (90.7% vs 92.3%), although specificity could be improved to 97.0% if the wider TSH reference limits of 0.1 to 20 milli-int. units/L were used--limits considered pathological if applied to outpatients. Evidently, different reference intervals for TSH are needed for hospitalized and nonhospitalized patients. We conclude that a "sensitive TSH assay" is not a cost-effective thyroid screening test for hospitalized patients as compared with the FT4I.

Adult↗
PubMed1986

The role of transferrin in natural killer cell and IL-2-induced cytotoxic cell function.

The growth factor transferrin (Tf) enhanced natural killer (NK) cell cytotoxicity. This enhancement was due to direct effects on NK cell function, and Tf treatment of the K562 target cell had no effect on their sensitivity. NK cells were highly enriched in the low-density large granular lymphocyte population (LGL) by Percoll gradient centrifugation. Despite the direct effect of Tf on NK cells, the number of cells expressing receptors for Tf (TfR) in NK-enriched LGL was the same as the NK-cell-depleted high-density small lymphocyte population (SL). All populations, tested without stimulation, had very few TfR+ cells. Interleukin 2 (IL-2) could induce very high NK-like activity in the LGL but not in SL. Similarly, only LGL could be induced by IL-2 to express TfR. In serum-free cultures, only limited NK-like activity could be developed which was greatly enhanced by supplementing with Tf in the cultures. The importance of Tf in NK-like development was confirmed by modulating the expression of TfR in IL-2 containing cultures with mouse monoclonal antibody OKT9 specific for TfR. OKT9 totally abrogated the induction of cytotoxic activity by IL-2 against K562 and NK-resistant target. OKT9 inhibited the induction of cytotoxicity in both lymphocytes containing active NK cells and in those predepleted of active NK cells, indicating that the development of NK-like activity from both precursor populations requires Tf. The inhibition by OKT9 was only during the induction phase. The same antibody had no effect on the cytotoxicity of fresh NK cells or the mature IL-2-induced NK-like cells. Our data therefore do not support the hypothesis of TfR as the NK recognition structure. Instead, these results indicate that Tf is important for the development of NK and NK-like activities.

Antibodies, Monoclonal↗
PubMed1986

An enzyme-linked immunosorbent assay for the detection of bovine antibodies to vesicular stomatitis virus.

An indirect enzyme-linked immunosorbent assay (ELISA) was developed to detect bovine antibody to vesicular stomatitis virus (VSV). Serum samples from cows experimentally infected with the New Jersey serotype of VSV (VSV-NJ) were assayed by the ELISA and serum-neutralization (SN) assay. The ELISA was as sensitive as the SN assay in detecting bovine antibody to VSV. The correlation between SN titers and ELISA values at absorbance at 405 nm was statistically significant. The ELISA was not specific for VSV-NJ, however, and could detect serum samples positive to the Indiana serotype of VSV that had SN titers of greater than or equal to 480. Nonspecific reactions were due to cross-reactive group-specific viral proteins that are shared by both serotypes. The cross-reactivity allows the use of a single rapid test in identifying both serotypes of VSV from the other exotic vesicular diseases, especially foot-and-mouth disease. The ELISA titers of serum samples positive for VSV-NJ were comparable with the corresponding SN titers of each sample. The sensitivity, rapidity, and ease of the ELISA system and the use of a single test in identifying both serotypes of VSV from the other exotic vesicular diseases make this ELISA suitable as a rapid diagnostic assay for VS.

Animals↗
PubMed1986

Ophthalmic rods. New ocular drug delivery devices.

Ophthalmic Rods, new drug delivery devices for ophthalmic medications, are 2-inch-long plastic rods coated with an ocular diagnostic or therapeutic agent. When the drug-coated tip of the rod is brought into contact with the conjunctiva, the medication dissolves into the tear film. We evaluated the safety, comfort, and ease of use of Ophthalmic Rods coated with fluorescein (30 micrograms) in 28 volunteers. Seventy-nine percent (22 of 28) of the patients rated the device as superior to eyedrops, citing cleanliness, comfort, and ease of application as the primary advantages. Ophthalmic Rods effectively delivered fluorescein to the eye and were found to be safe in patients with various refractive conditions, including those with compromised near vision and accommodation.

Conjunctiva↗
PubMed1985

Multiply drug-resistant human KB carcinoma cells have decreased amounts of a 75-kDa and a 72-kDa glycoprotein.

Human KB carcinoma cells were selected in sequential steps for resistance to colchicine and found to be cross-resistant to multiple drugs, including vinblastine, adriamycin, and actinomycin D. Compared with the parental line, the multiply resistant cells have decreased amounts of two [35S]methionine-labeled proteins with apparent molecular masses of 75 and 72 kDa. These proteins reappear in a revertant, drug-sensitive cell line. Both proteins are labeled with [14C]glucosamine and are retained on a wheat germ agglutinin-agarose column, indicating that they are glycoproteins. These data suggest that in this human cell line, these two glycoproteins can serve as a marker of the multiple drug-resistance phenotype and may play a role in its etiology.

Antineoplastic Agents↗
PubMed1981

Rapid identification of Enterobacteriaceae with microbial enzyme activity profiles.

A total of 539 clinical isolates belonging to 10 species of the Enterobacteriaceae family were identified by enzyme activity profiles within 30 min of test inoculation. Each isolate was grown at 37 degrees C for 18 h on Mueller-Hinton agar and suspended to an optical density of 200 Klett units on 0.85% saline. Enzyme activity profiles were obtained by inoculating 18 fluorogenic substrates with the standardized bacterial suspension and monitoring initial rates of hydrolysis over the first 30 min of analysis. Individual enzyme activity profiles were entered into a coded data bank, and identifications were based on the Bayesian theory of probabilities. At a confidence level of 95%, five species were identified with a greater than 90% efficiency, three species were identified between 83 and 88% efficiency, and two species demonstrated a 72 and 75% efficiency of identification. The enzyme activity profile method of bacterial identification is rapid, easily automated, and reproducible.

Aminopeptidases↗