Search PubMed⌕ Search

Biomedical subjects

K Yang

Publications and source records attributed to K Yang.

At least 343 records · Page 19Linked to original sources
PubMed1983

Hairy cell leukemia: a B cell neoplasm with a unique antigenic phenotype.

A panel of B, T, and monocyte antibodies was used to study the phenotype of hairy cell leukemia. It was found that the neoplastic cells had monoclonal surface immunoglobulins and, in addition, reacted with B1, HLA-DR, Leu 10, and Tac. Most of the above markers are features of B cell lymphocytes. However, Tac is a monoclonal antibody normally reactive with activated T lymphocytes. All other antibodies reactive with T cells were negative. An additional unexpected finding was intranuclear reactivity in 4/5 cases with an antibody to TdT. TdT enzymatic activity was not demonstrable by biochemical assay. All five cases were nonreactive with monocyte antibodies. The findings support the concept that hairy cell leukemia is of B cell lineage but demonstrates an unusual phenotype not seen in other normal or neoplastic B lymphocytes.

Adult↗
PubMed1982

Acid phosphatase and alpha-naphthyl acetate esterase in neoplastic and non-neoplastic lymphocytes. A statistical analysis.

Acid phosphatase and alpha-naphthyl acetate esterase reaction patterns were evaluated in lymphocytes from patients with a variety of neoplastic and non-neoplastic conditions: leukemia, 59; NHL, 53; and reactive follicular hyperplasia, 23. Fifteen individuals with normal peripheral blood were also studied. For both enzymes, statistical analysis showed a strong correlation between a globular reaction pattern and T lymphocytic origin in both non-neoplastic lymph nodes and normal peripheral blood specimens (P less than 0.0001). A similarly strong correlation was found between a granular acid phosphatase pattern and T lymphocytic origin in cell isolated from non-neoplastic lymph nodes (P less than 0.0001) but not in those obtained from normal peripheral blood where this pattern was observed with equal frequency in B, T, and "null" lymphocytes (P = 0.415). A granular alpha-naphthyl acetate esterase pattern was correlated with non-T lymphocytes from normal peripheral blood (P less than 0.0001), but was observed with equal frequency in B, T, and "null" lymphocytes fron non-neoplastic lymph nodes (P = 0.76). In the eight T cell neoplasias studied, a globular pattern was evident in the majority of cells for both enzymes. In the majority of the B cell neoplasias, however, a granular pattern was observed for both enzymes.

Acid Phosphatase↗
PubMed1982

Physiochemical properties of aminophylline-dextrose injection admixtures.

The compatibility and stability of aminophylline-dextrose injection admixtures were investigated. Aliquots of 5% dextrose injection, 0.9% sodium chloride injection, and 5% dextrose and 0.9% sodium chloride injection were studied for these physiochemical properties: pH, color, clarity, absorbance in a spectrophotometer at 400 nm, and hydroxymethylfurfural (HMF) content. Aminophylline injection was added to the solutions, and aliquots were withdrawn after 0, 6, 24, and 48 hours of storage at 5, 25, 35, and 55 degrees C for testing of the physiochemical properties and aminophylline content. An aminophylline admixture in 5% dextrose injection was passed through an in-line filter (IVEX-2), and eluents were collected for aminophylline assay and for testing the above physiochemical properties. HMF and theophylline were assayed to high-pressure liquid chromatography (HPLC). The aminophylline concentration remained constant in all admixtures studied. A yellow color developed in dextrose-containing aminophylline admixtures stored at 25, 35, and 55 degrees C for 48, 24, and 6 hours, respectively. HMF concentration, pH, and clarity remained within compendial limits. The in-line filter did not retain active ingredients or alter the physiochemical properties of the admixture. Solutions that were yellow showed additional peaks on HPLC. HMF seemed to be a precursor for this yellow color, inasmuch as HMF concentration increased with increasing color intensity. It is concluded that aminophylline-dextrose admixtures are visually and chemically stable for 48 hours when stored under refrigeration or at room temperature.

Aminophylline↗
PubMed1981

Interferons, double-stranded RNA, and RNA degradation. Isolation and characterization of homogeneous human (2'-5')(a)n synthetase.

(2'-5')(A)n synthetase is one of the mediators of interferon action. If activated by double-stranded RNA it converts ATP into pyrophosphate and (2'-5')(A)n. In turn, (2'-5')(A)n activates a latent endoribonuclease (RNase L) which cleaves single-stranded RNA. We report here the isolation and characterization of a homogeneous human (2'-5')(A)n synthetase. The enzyme was purified from interferon-treated HeLA S3 cells by chromatography of a ribosomal salt wash fraction on DEAE-cellulose, poly(I) . poly(C) agarose, and CM-cellulose. The purified (2'-5')(A)n synthetase can convert over 90% of ATP into (2'-5')(A)n. The enzyme is unstable but can be stabilized by certain nonionic detergents (e.g. Triton X-100). Its apparent Mr = 100,000, as determined by gel electrophoresis in sodium dodecyl sulfate, and about 80,000, as determined by centrifugation through a glycerol gradient. The human (2'-5')(A)n synthetase is similar to the corresponding enzyme from mouse Ehrlich ascites tumor cells, but differs from the latter in size (100,000 versus 105,000 daltons) and in ionic conditions required for maximal activity.

2',5'-Oligoadenylate Synthetase↗
PubMed1981

Intravenous solution compatibility and filter-retention characteristics of trace-element preparations.

The compatibility of recently published AMA formulations of the four trace-element injections (zinc, copper, chromium, and manganese) with a representative total parenteral nutrition (TPN) formulation and commonly used intravenous solutions was evaluated in glass and plastic containers. The effect of in-line filtration on trace-element concentration was also studied. Individual metal-ion concentrations, pH, color, and clarity were measured at 0-, 12-, 24-, and 48-hour intervals following mixture in TPN, 5% dextrose injection, 0.9% sodium chloride injection, and 8.5% amino acid injection (Travasol, Travenol Laboratories). Multiple trace elements were studied in one-liter glass bottles of 5% dextrose and 0.9% sodium chloride injection. Trace-element contaminants were measured in the intravenous solutions and trace-element injections. The four trace-element preparations were added individually and in combination to the solutions in plastic or glass containers. The trace-element admixtures were passed through in-line i.v. filters (IVEX-2, Abbott Laboratories) during a three-hour period at controlled-flow rates. Concentrations of trace elements remained within 99% confidence limits in all i.v. solutions, with both individual trace elements and combinations of the four trace elements. Trace-element concentrations did not change when the admixtures were passed through the in-line filter unit. It is concluded that there are no obvious compatibility problems associated with admixture nor any detectable retention by the i.v. filter of trace elements.

Drug Incompatibility↗
PubMedDate not supplied

Modulation of abnormal colonic epithelial cell proliferation and differentiation by low-fat dairy foods: a randomized controlled trial.

CONTEXT: Before the development of human colonic neoplasms, colonic epithelial cells showed altered growth and differentiation. These alterations characterized mucosa at risk for cancer formation and were termed intermediate biomarkers of risk. Modifications of the mucosa toward more normal features by nutrients or drugs are putative approaches to chemoprevention of colon cancer. OBJECTIVE: To determine whether increasing calcium intake via dairy products alters colonic biomarkers toward normal. DESIGN: Randomized, single-blind, controlled study. SETTING: Outpatient clinic. PARTICIPANTS: Seventy subjects with a history of polypectomy for colonic adenomatous polyps. INTERVENTION: Low-fat dairy products containing up to 1200 mg/d of calcium. Subjects were randomized to 4 strata by diet (control vs higher calcium) and age (<60 vs > or = 60 years). MAIN OUTCOME MEASURES: Changes in total colonic epithelial cells and number and position of thymidine-labeled epithelial cells and changes in the ratio of sulfomucins (predominantly secreted by distal colorectal epithelial cells) to sialomucins and expression of cytokeratin AE1, 2 markers of colonic cell differentiation. RESULTS: During 6 and 12 months of treatment, reduction of colonic epithelial cell proliferative activity (P<.05), reduction in size of the proliferative compartment (P<.05), and restoration of acidic mucin (P<.02), cytokeratin AE1 distribution (P<.05), and nuclear size (P<.05) toward that of normal cells occurred. Control subjects showed no differences from baseline proliferative values at 6 and 12 months (P>.05). CONCLUSION: Increasing the daily intake of calcium by up to 1200 mg via low-fat dairy food in subjects at risk for colonic neoplasia reduces proliferative activity of colonic epithelial cells and restores markers of normal cellular differentiation.

Adenomatous Polyposis Coli↗