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Biomedical subjects

S Davis

Publications and source records attributed to S Davis.

At least 577 records · Page 32Linked to original sources
PubMedDate not supplied

Distinct alpha-L-fucosidase isoenzyme profiles in human leukemic cells.

alpha-L-Fucosidase (EC 3.2.1.51; FUS) activity and isoenzyme characteristics were analyzed in normal lymphocytes, normal granulocytes (PMNs) and myeloid and lymphoid leukemic cells, (AML, AMMoL, ALL, CLL and CML). CLL lymphocytes had a lower mean specific activity than normal lymphocytes (2.5 v 4.0, p less than 0.05). ALL blasts had a higher mean specific activity compared to normal lymphocytes (9.7 v 4.0; p less than 0.001), CLL lymphocytes (9.7 v 2.5; p less than 0.001) and AML blasts (9.7 v 7.6 p = NS). Normal PMNs had a higher mean specific activity than normal lymphocytes (7.0 v 4.0 p less than 0.05) but similar activity when compared to CML cells or AML blasts. Blasts from AMMoL patients had higher activity than normal PMNs (9.0 v 7.0; p less than 0.05). The isoenzyme patterns of normal and leukemic granulocytes and lymphocytes were obtained by automated chromatofocusing on PBE-94 microcolumns with normal and leukemic lymphocyte lysates. With normal and leukemic lymphoid lysates two major isoenzyme components (B and A) were isolated. The isoenzyme pattern of PMN, AML, CML and AMMoL revealed 3 major peaks (B, A, I), totally different from that seen in lymphoid cells. The patterns of AML, CML and PMN appeared to be similar to each other; however, the isoenzyme pattern obtained from AMMoL cells could be distinguished from the others by a prominent I peak. Thus the FUS isoenzyme profile distinguishes the blasts of AMMoL from AML, and AMMoL and AML from ALL.

Humans↗
PubMedDate not supplied

Neonatal status: an objective scoring method for identifying infants at risk for poor outcome.

The likelihood of sustaining neurological, sensory or cognitive deficits is considerably greater for very low birthweight (VLBW) infants who require intensive care in early postnatal life than those without major neonatal illness. Identifying which, if any, medical events are responsible for an adverse outcome is most difficult in the face of multiple concurrent complications. In this research, a principal components analysis was performed in order to arrive at a set of orthogonal variables which succinctly described clinical involvement in the nursery. With this procedure, a single hypothetical factor depicting neonatal status (NS) was computed. Principal component scores were then generated for NS and assigned to 252 VLBW (less than 1500 g) infants. These subjects were followed prospectively from birth to 4 years of age. Standardized measures of neurological, sensory and intellectual function were regularly administered. Neonatal status was shown to be significantly correlated with the various test results and predictive of long-term development. When subjects were divided into quartiles with respect to NS, a specific subgroup was identified as "at high risk" for poor outcome. Those subjects falling into the lower quartile incurred more neurological abnormalities persisting beyond the first year. They also suffered a higher incidence of intracranial hemorrhage and sensori-neural hearing loss. In addition, the lower 25%, as a group, scored well below all others on traditional tests of mental ability. These differences were sustained throughout infancy and early childhood and could not be attributed to a number of demographic variables including sex, gestational age, birthweight, Apgar scores or parental educational level.

Child Development↗
PubMedDate not supplied

Metastatic spindle cell carcinoma: a complete response induced by cisplatin and 5-fluorouracil.

A patient with biopsy-proven spindle cell carcinoma, of unknown primary site, metastatic to the neck and to the lung, was treated with chemotherapy consisting of cisplatin (20 mg/m2/day) on days 1-5 and 5-fluorouracil (1000 mg/m2/day) on days 1-5. The regimen was repeated every 28 days. The patient had a complete response confirmed by computerized tomography. The patient is in a disease-free status 12 months after diagnosis. Toxicity was mild. To our knowledge, this case represents the first chemotherapy induced complete response documented in this rare entity.

Adult↗
PubMedDate not supplied

Chemotherapeutic trials with hamster mesothelioma 10-24: responses to azacitidine, aziridinylbenzoquinone, cisplatin, and PCNU.

Asbestos-induced peritoneal mesothelioma 10-24 serially transplanted in Syrian golden hamsters was used to test responses to seven drugs as single agents. Compared to saline-treated controls, the average survival time increased 51%-85% with azactitidine, 42%-60% with aziridinylbenzoquinone, 43% with cisplatin, and 35%-45% with PCNU. No cures were achieved. Therapeutic responses were not observed with dactinomycin, dianhydroxyanthracenedione, or DTIC.

Animals↗
PubMedDate not supplied

Single-agent and combination chemotherapy for extensive non-small cell carcinomas of the lung.

One hundred and twenty-four patients with extensive bronchogenic carcinoma were randomized to one of three chemotherapeutic regimens. Forty-one patients received cyclophosphamide (600 mg/m2 every 3 weeks) (group 1); 47 patients received cyclophosphamide (600 mg/m2 every 3 weeks) and CCNU (70 mg/m2 every 6 weeks) (group 2); and 36 patients received cyclophosphamide (600 mg/m2 every 3 weeks), CCNU (70 mg/m2 every 6 weeks), and doxorubicin (40 mg/m2 every 3 weeks) (group 3). The objective response rates were 5%, 8%, and 6% in groups 1, 2, and 3, respectively (P greater than or equal to 0.3). Median survival times were 20.5 months (group 1), 17.8 months (group 2), and 18.8 months (group 3). There was no significant difference in median survival between groups (P greater than or equal to 0.4). Responders in each group survived longer than nonresponders. Hematologic toxic effects were severe in group 3 and moderate in group 2. Since combination chemotherapy with cyclophosphamide and doxorubicin or cyclophosphamide, doxorubicin, and CCNU is not superior to cyclophosphamide as a single agent and is associated with greater toxicity, these combinations are not recommended as therapy for extensive bronchogenic carcinoma.

Adenocarcinoma↗
PubMedDate not supplied

alpha-L-Fucosidase activity and isoenzyme characteristics analyzed by chromatofocusing in normal and leukemic lymphocytes.

alpha-L-Fucosidase (EC 3.2.1.51) activity and isoenzyme characteristics were analyzed in normal lymphocyte subpopulations, chronic lymphocytic leukemia subpopulations, and acute lymphoblastic leukemia blasts. Similar pH activity profiles revealed that pH 5.0 was optimal in normal and leukemic cells. Unfractionated CLL lymphocytes had a lower specific activity than normal unfractionated lymphocytes (2.5 +/- 1.0 u/10(6) cells v. 4.0 +/- 1.1). CLL B cells and T-cells had lower specific activity than their respective normal counterparts (1.8 +/- 0.2 v. 5.9 +/- 2.0) (B-cells); (2.2 +/- 0.5 v. 3.7 +/- 1.0) (T-cells) suggesting T and B cells in CLL are abnormal. ALL blasts had a higher specific activity compared to unfractionated normal lymphocytes (9.7 +/- 3.0 v. 4.0 +/- 1.1; p less than 0.001). The isoenzyme pattern of normal, CLL and ALL lymphocytes were obtained by automated chromatofocusing on PBE 94 microcolumns using 0.025 M histidine and polybuffer 74. Two major isoenzyme components (B and A) were isolated. The activity ratio of B/A was different in normal, ALL, and CLL cells.

B-Lymphocytes↗
PubMedDate not supplied

Polyvinyl alcohol foam-Gelfoam for therapeutic embolization: a synergistic mixture.

Gelfoam and polyvinyl alcohol foam particles each have advantages and disadvantages for therapeutic embolization. It was theorized and confirmed that a mixture of the two retains the advantages and eliminates the disadvantages of each. Two mixtures were prepared, tested in animals, and used successfully in 14 patients. It was found that the mixtures of Gelfoam and polyvinyl alcohol foam particles fulfilled the expectations and needs for particulate embolic materials.

Adrenal Gland Neoplasms↗
PubMedDate not supplied

Adenosine deaminase, nucleoside phosphorylase and hypoxanthine-guanine phosphoribosyltransferase activity in normal lymphocyte subpopulations.

Adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), and hypoxanthine-guanine phosphoribosyltransferase (HGPRT) activities were measured in normal human B lymphocytes, T lymphocytes, and T gamma and T mu lymphocyte subsets. Total ADA activity in T cells was 5.5U, activity in T gamma and T mu cells was 3.7U and 5.3U, respectively; B cell ADA levels were 3.3U. PNP activity in T cells was 119U, activity in T gamma and T mu cells was 75U and 155U, respectively. B cell PNP activity was 88U. HGPRT activity in T cells was 20.9U; T gamma and T mu HGPRT levels were 13.0U and 52U respectively. B cell HGPRT levels were 46.8U. These data provides further evidence for the biochemical heterogeneity of normal human lymphocytes.

Adenosine Deaminase↗
PubMedDate not supplied

Combination cyclophosphamide, doxorubicin, and cisplatin (CAP) chemotherapy for extensive non-small cell carcinomas of the lung.

Fifty consecutive patients with extensive non-small cell carcinoma of the lung were randomized to one of two chemotherapeutic regimens. Twenty-three patients (group 1) received cyclophosphamide (600 mg/mg(2)), doxorubicin (40 mg/m(2)), and cisplatin (50 mg/m(2)) every 3 weeks; 27 patients (group 2) received cyclophosphamide (600 mg/m(2)), doxorubicin (40 mg/m(2)), and cisplatin (100 mg/m(2)) every 3 weeks. The objective response rates were 4% and 7% in groups 1 and 2, respectively. Median survival duration was 15.2 weeks (group 1) and 21.7 weeks (group 2; P greater than or equal to 0.3). Hematologic toxicity was minimal in group 1 and moderate in group 2. Renal toxicity was moderate in group 2 only. Combination chemotherapy with cyclophosphamide, doxorubicin, and cisplatin as used in this study is not superior to previous studies in this institution using cyclophosphamide as a single agent.

Aged↗
PubMedDate not supplied

cis-Dichlorodiammineplatinum(II) in the treatment of esophageal carcinoma.

Seventeen consecutive patients with untreated squamous cell carcinoma of the esophagus were treated with cis-dichlorodiammineplatinum(II) (DDP) by infusion at a dose of 3 mg/kg with mannitol diuresis. One patient had a partial response and six additional patients had subjective improvement in dysphagia and associated weight gain; however, no complete responses were noted. Toxic effects were mainly renal. There were no drug-related deaths. We conclude that DDP alone is not effective in squamous cell carcinoma of the esophagus.

Aged↗
PubMedDate not supplied

Immunosuppressive properties and circulating life of Achromobacter glutaminase-asparaginase covalently attached to polyethylene glycol in man.

The immunosuppressive effects and circulating life of Achromobacter glutaminase-asparaginase (GA) covalently attached to polyethylene glycol (PEG) were examined in human subjects following a single iv dose of 1000 IU/m2. Plasma half-life of PEG-GA was 72 hours. Skin test reactivity to recall antigens (mumps and tuberculin) was lost in all four patients tested. In vitro phytohemagglutinin-induced blastogenesis, "natural killing," and phytohemagglutinin-induced cell cytotoxicity was diminished as long as enzyme levels were detectable. In vivo and in vitro activities returned to normal following total plasma clearance of enzyme.

Aged↗
PubMedDate not supplied

Developing a competency-based preventive medicine curriculum for medical schools.

Trends in patient morbidity and mortality, cost-effectiveness, and national recommendations mandate that we practice more preventive medicine. To address this need, we set out to develop a comprehensive curriculum in preventive medicine for medical schools. We constructed a competency-based (i.e., performance-based) curriculum with specific educational objectives defined by outcomes. Subject areas were subdivided by life stages, and learning objectives were created separately for epidemiology, assessment, and intervention. We hope that adoption of such an educational blueprint by medical schools will measurably enhance the attitudes, knowledge, and skills necessary for the incorporation of preventive principles into all aspects of clinical medicine.

Clinical Competence↗
PubMedDate not supplied

Consumption of nitrate, nitrite, and nitrosodimethylamine and the risk of upper aerodigestive tract cancer.

Evidence from animal studies indicates that various N-nitroso compounds are carcinogenic. We investigated whether consumption of foods and beverages containing nitrosodimethylamine, nitrites, and nitrates affected the risk of laryngeal, esophageal, and oral cancer. In a population-based case-control study in western Washington state, dietary consumption of these substances was measured in 645 cases (169 laryngeal, 125 esophageal, and 351 oral) and 458 controls. After adjustment for tobacco, alcohol, and other known risk factors, there was a 52% reduction in the risk of upper aerodigestive tract cancer for individuals who consumed higher amounts of nitrate (upper tertile) compared with the lowest tertile (P < 0.001 for trend). Nitrate intake was associated with a reduction in cancer risk at all three sites. The reduction in the risk of esophageal cancer with increasing nitrate consumption was more evident in frequent tea drinkers than in other subjects. There was no significant association between nitrite consumption and the risk of laryngeal or oral cancer. However, for individuals with a history of canker sores (an indicator of possible endogenous nitrosation), the risk of esophageal cancer was seven times greater in those with high versus low nitrite intake. Consumption of foods high in nitrosodimethylamine was associated with a 79% increased risk of upper aerodigestive tract cancer (P = 0.037 for trend). Cases consumed smoked fish more frequently than did controls [odds ratio (OR) = 3.03]. Daily intake of beer and of nitrite-containing meats were associated with an increased esophageal cancer risk (OR = 2.48 and 1.82, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Alcohol Drinking↗