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Biomedical subjects

S Davis

Publications and source records attributed to S Davis.

At least 415 records · Page 23Linked to original sources
PubMed1984

A distinct beta-hexosaminidase isoenzyme separated from human leukemic lymphocytes and myelocytes.

The beta-hexosaminidase (EC 3.2.1.30) isoenzymes were separated on the basis of their carbohydrate moieties by an affinity chromatography using immobilized phenylboronate. Normal lymphocytes and granulocytes contain two major forms of beta-hexosaminidase, acute lymphoblastic, acute myeloblastic, chronic lymphocytic and chronic myelocytic leukemic cells contain an extra, distinct isoenzyme of beta-hexosaminidase. This extra isoenzyme may be a marker for the leukemic conversion of hematopoietic tissue.

Bone Marrow↗
PubMed1984

Monoclonal antibody-defined T-cell phenotypes and phytohemagglutinin reactivity of E-rosette-forming circulating lymphocytes from untreated chronic myelocytic leukemia patients.

T-cell phenotypes, as defined by murine monoclonal antibodies, (OKT3, OKT4, OKT8, OKIa1), and phytohemagglutinin (PHA) reactivity, were evaluated in E-rosette forming cells (T-cells) from 10 untreated chronic myelocytic leukemia patients. The proportion of T4+ cells was lower in patients than in controls (41.6 versus 61.7%, P less than 0.02); whereas the proportion of T8+ cells was similar in patients and controls. The decrease in T4+ cells in CML resulted in a decrease in circulating T4+/T8+ ratio (P less than 0.02). The Ia1+ T-cells were increased in most CML (8 of 9) patients, while control subjects never displayed Ia1+ T-lymphocytes (P less than 0.01). The PHA reactivity of E-rosette forming lymphocytes was significantly impaired in CML patients with respect to controls (P less than 0.02). The presence of Ia antigen on T-cells was positively correlated with the T8+ cell phenotype (P less than 0.001) and inversely correlated with the T4+ (helper) cell phenotype (P less than 0.05). Furthermore, there was a trend towards an inverse correlation between the PHA response and the level of Ia1+ or T8+ cells, there is no correlation between PHA reactivity and T4+ phenotype. The results suggest that the T-lymphocyte population from untreated CML patients is intrinsically abnormal.

Adult↗
PubMed1984

A mature thymocyte-like phenotypic pattern on human cord circulating T-lymphoid cells.

Cord blood samples from healthy full-term newborns were tested with antimature and antiimmature lymphoid-cell monoclonal antibodies, as well as more traditional markers, in order to identify the phenotype of circulating precursor cells. The results demonstrated that human cord blood contains a lower number of OKT3+, E-rosetting mature T cells than adult blood, very high levels of OKT10+ cells, and few OKT9+, OKT8+ OKT3-, and OKT4+ OKT3- cells. Although the finding of OKT9+ and OKT10+ cord circulating cells could be indicative of cell activation, double marker studies in newborn blood pointed to phenotypically immature lymphoid subsets at different stages of maturation, according to Reinherz's hypothesis. In addition, the absence of nuclear Tdt-positive and hot-rosetting cells, together with the fact that most of these are OKT3+, OKT10+, OKT4+, or OKT8+ cells, suggests that the surface phenotype of newborn lymphocytes is similar to that of mature thymocytes.

Antibodies, Monoclonal↗
PubMed1984

CT patterns of splenic infarction: a clinical and experimental study.

The computed tomographic (CT) appearance of splenic infarction has classically been described as peripheral, wedge-shaped, and low in density. Two investigations were designed to determine the appearance of splenic infarcts: (a) a clinical study of 12 patients and (b) a canine experimental model. In the clinical study, two previously undescribed patterns of splenic infarction were found. The classic peripheral, wedge-shaped defects were seen in four patients; multiple, heterogeneous lesions were seen in five; and massive hypodense lesions were noted in three. In three of the nine patients who had both precontrast and postcontrast CT scans, the unenhanced images alone would not have permitted the diagnosis. Contrast enhancement markedly improved infarct visualization in the remaining six. The experimental study of splenic infarction in dogs indicated that CT images can accurately depict the various phases of an infarct as it evolves through stages of congestion, hemorrhage, inflammation, organization, and fibrosis. In addition, a new contrast material--liposome-encapsulated diatrizoate--was used in one of the dogs and was found to produce greater and more sustained differences between normal and abnormal tissue than did conventional contrast material.

Adolescent↗
PubMed1984

Intrapericardial tetracycline sclerosis in the treatment of malignant pericardial effusion: an analysis of thirty-three cases.

Thirty-three unselected patients with cardiac tamponade secondary to malignant pericardial effusion were treated by intrapericardial instillation of tetracycline hydrochloride. Complete control of the initial signs and symptoms of tamponade was obtained in 30 patients without concomitant chemotherapy or radiotherapy. The procedure did not result in clinically significant complications. Failure of the technique was related to premature removal of the catheter by the patient (one patient) or the inability to totally remove hemorrhagic, clot-filled pericardial fluid (two patients). Survival ranged between 28-704 days and extended survival was related to the performance status and/or chemoradiosensitivity of the primary cancer. No patient successfully treated subsequently developed recurrent cardiac tamponade or alternatively, constrictive pericarditis. Tetracycline pericardial instillation remains a safe, simple, and efficacious treatment of tamponade secondary to malignant disease.

Adult↗
PubMed1983

The in vivo effect of thymic factor (thymostimulin) administration on circulating immune complexes and serum lysozyme levels in untreated Hodgkin's disease patients.

The in vivo effect of a calf thymus extract, thymostimulin, on the levels of circulating immune complexes (CIC) and serum lysozyme was evaluated in 32 patients with untreated Hodgkin's disease. Using the platelet aggregation test for detecting CICs, 12 patients (37%) had positive titers before thymostimulin treatment; 3 patients (10%) remained positive following therapy. Serum levels of Clq-binding immune complexes were evaluated (greater than 24.5 micrograms/ml) in 8 patients prior to thymostimulin therapy (mean value: 42.3 micrograms/ml); 3 patients continued to have elevated levels after treatment. Serum lysozyme levels for Hodgkin's patients was similar to control values (10.6 vs. 8.3 micrograms/ml); however, the Hodgkin's patients with initially elevated CICs had a lower serum lysozyme level than patients with initially normal CICs (12.9 vs. 7.3, p less than 0.02). Thymostimulin increased serum lysozyme levels in the Hodgkin's patients in whom the CICs were initially elevated (7.3 vs. 10.4 micrograms/ml, p less than 0.05). These data suggest that thymostimulin exerts an effect on the nonspecific immune system of Hodgkin's disease patients.

Animals↗
PubMed1983

Immunohistochemistry of a gross cystic disease fluid protein (GCDFP-15) of the breast. A marker of apocrine epithelium and breast carcinomas with apocrine features.

Gross cystic disease fluid is a pathologic secretion from breast composed of several glycoproteins, including a unique 15,000-dalton monomer protein, GCDFP-15. By the immunoperoxidase technique, GCDFP-15 was localized in the apocrine metaplastic epithelium lining breast cysts and in apocrine glands in the axilla, vulva, eyelid, and ear canal. In normal breast tissue, a few individual epithelial cells within lobules and small ducts were focally positive for GCDFP-15. Fourteen of 30 breast carcinomas stained positively for GCDFP-15. Of 16 carcinomas with apocrine features, 12 stained positively. Benign and malignant lesions from other tissues, including lung, colon, ovary, endometrium, stomach, prostate, liver, esophagus, and kidney, revealed no immunoreactivity. The only cells of "non-apocrine" tissues that contained GCDFP-15 were serous cells of the submandibular salivary gland, submucosal glands of the bronchi, and accessory lacrimal glands. Phylogenetically, these tissues have biologic features in common with apocrine glands. This report is the first to characterize GCDFP-15 as a specific tissue marker of apocrine epithelium.

Adenofibroma↗
PubMed1982

Alcohol and drowning in Cape Town. A preliminary report.

The literature on alcohol and drowning is reviewed, and the possible mechanisms of action of alcohol in drowning discussed. A 3-year enquiry into the role of alcohol in drowning in greater Cape Town shows that a large percentage of adult victims of drowning were under the influence of alcohol at the time. Recommendations are made to increase public awareness of the hazards related to the consumption of alcohol while engaging in aquatic activity.

Adolescent↗
PubMed1982

Levamisole as an adjuvant to chemotherapy in extensive bronchogenic carcinoma: a Veterans Administration Lung Cancer Group Study.

A randomized trial of 381 patients with extensive lung cancer compared immunochemotherapy with levamisole (150 mg/m2 orally three times a week), cyclophosphamide (700 mg/m2 IV every three weeks) and CCNU (70 mg/m2 orally every six weeks) with the same chemotherapy without levamisole. When disease progressed, doxorubicin hydrochloride or doxorubicin hydrochloride plus levamisole was used. Hematologic toxicity required reduction of the levamisole dosage to 2.5 mg/kg (100 mg/m2) three times a week, every other week. When corrections are made for all variables, levamisole itself had a negative influence on survival. Patients given 150 mg/m2 had a shorter median time to treatment failure (P = 0.02), lower response rate (P = 0.02) more toxicity (P = 0.08), and shorter median survival (P = 0.08). Patients with 10% or greater weight loss had significantly shorter survival (P = 0.006). The regimen with the reduced dosage of levamisole also was more toxic (P = 0.05) but otherwise did not differ from the control regimen. The cause of the adverse effect of levamisole is unknown. It did not occur because of an excess of toxic deaths or because smaller doses of cytotoxic drugs were given to patients treated with levamisole. Neither the initial lymphocyte count nor the Candida skin test reactions had a significant effect on the study endpoints when correction was made for dominant prognostic factors such as the initial performance status and weight loss.

Carcinoma, Bronchogenic↗
PubMed1982

The in vivo effect of a thymic factor (thymostimulin) on immunologic parameters of patients with untreated Hodgkin's disease.

The in vivo effect of a calf thymus extract (thymostimulin, TS) on the E-rosetting capacity, PHA blastogenic response, serum migration inhibitory activity (LIF) and skin reactivity to recall antigens was evaluated in 19 untreated patients with Hodgkin's disease. In patients the mean percentage of peripheral blood lymphocytes forming E-rosettes increased from 47 to 55.7% (P less than or equal to 0.001; normal: 58.9). The mean PHA stimulation index rose with all three concentrations tested but did not reach normal values. Serum LIF was positive in only one patient prior to treatment with a mean LIF for all patients of 0.75 (P less than or equal to 0.005). Skin tests were positive in ten patients (52.6%) prior to therapy and 18 patients following therapy (94.7%; P less than or equal to 0.05). Thymostimulin, in vivo, appears to return immunologic competency to a population of untreated patients with Hodgkin's disease.

Adult↗
PubMed1982

Cell membrane markers and phytohemagglutinin reactivity of circulating lymphocytes from chronic myelocytic leukemia patients.

Lymphocytes from 22 patients with chronic myeloid leukemia (CML), 13 treated with polychemotherapy, eight by monochemotherapy, and one untreated, were analyzed for the presence of classic T and B cell surface markers (E-rosette, EAC-rosette, surface immunoglobulins) and for their ability to respond to phytohemagglutinin (PHA). The absolute number and percentage of E-rosetting cells (T-cells), EAC-rosetting cells and cells staining for surface immunoglobulins (B cells) were all significantly lower than controls (P less than or equal to 0.025). The response to PHA was also significantly lower in patients than in controls at the smaller concentrations of the mitogen (3.75 micrograms/ml, 30 micrograms/ml) tested (P less than or equal to 0.01); at a higher PHA concentration (120 micrograms/ml) the decrease in PHA stimulation approached significance (P = 0.07). These lymphocyte abnormalities support the concept that CML lymphocytes may be derived from the leukemic clone.

Adult↗
PubMed1982

The in vitro effect of a calf thymus extract (thymostimulin) on the immunologic parameters of patients with untreated Hodgkin's disease.

The in vitro effect of a calf thymus extract, thymostimulin (TP--1), on the E-rosette-forming capacity and on the PHA blastogenic response of peripheral blood lymphocytes was evaluated in 20 patients with untreated Hodgkin's disease. The mean percentage of lymphocytes forming E rosettes increased in patients from 44.2% to 57.5% (P less than 0.005). The mean PHA stimulation index rose with all three concentrations tested, but returned to the normal range only with the highest PHA concentration (60 mu/ml). An increase in the immune parameters was greatest in those patients who presented with decreased E-rosetting cells of total lymphocyte counts or whose disease was Stage III or IV or of mixed cellular histology.

Adolescent↗
PubMed1982

Cognitive processes in depression.

Tested hypotheses derived from Beck's cognitive theory of depression using 60 depressed and nondepressed males and females. Ss rated performance before and after they received feedback on a social interaction task. Ss then attempted to recall feedback and explain their post-feedback self-rating. Results showed that depressed males and females had more negative evaluation of present circumstances and poorer memory for feedback. Further, depressed males lowered their self-evaluation after feedback significantly more than did nondepressed males. Results with regard to differential response to neutral and positive feedback were not found because Ss apparently perceived all levels of feedback as somewhat negative. Data were partially supportive of Beck's cognitive theory of depression, especially with regard to males.

Adult↗
PubMed1982

Surface immunoglobulins on hairy cells of 55 patients with hairy cell leukemia.

Surface immunoglobulins (SIg) were determined on peripheral blood samples from 55 patients with hairy cell leukemia (HCL) and on hairy cells from spleen preparations of 14 of these 55 patients. The patterns of SIg for HCL was compared to the patterns on peripheral blood leukemic cells from 39 patients with chronic lymphocytic leukemia (CLL) and 15 patients with poorly differentiated lymphocytic (PDL) lymphoma. Of the 55 HCL patients, 42 could be scored for individual heavy and light chains; 16 had only IgG, 14 had two or three heavy chains, 7 had only IgD, and 5 cases had no SIg and were E-rosette negative. This pattern was different from the B-cell pattern in CLL and PDL where there were few cases of IgG alone (5%) and many cases of IgM alone (50%). Surface marker profile did not correlate with survival in any of the sub-groups tested. HCL appears to be a B-cell lymphoproliferative disease in greater than 90% of cases; many combinations of heavy chains with only a single light chain can be demonstrated.

Cell Transformation, Neoplastic↗
PubMed1982

Adjuvant treatment of node-positive breast cancer with adriamycin-cyclophosphamide with or without radiation therapy: interim results of an ongoing clinical trial.

During 1974-1980, 138 women with node-positive stage II breast cancer were treated with either eight courses of adriamycin-cyclophosphamide (AC) chemotherapy (82 patients) or AC chemotherapy plus comprehensive regional radiotherapy (56 patients). The overall relapse-free survival of the treated patients was significantly superior (P less than 0.001) to a comparable group of women who underwent surgery alone. This effect of adjuvant therapy was clearly manifest in all groups of patients irrespective of nodal involvement or menopausal status. To date, relapse-free survival for patients receiving AC compared to AC plus radiotherapy is not different (P = 0.7). In summary, wer have demonstrated that a brief 6-month course of adjuvant chemotherapy with AC can significantly reduce the recurrence rate in women with stage II breast cancer.

Adult↗