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Biomedical subjects

S E Martin

Publications and source records attributed to S E Martin.

At least 127 records · Page 7Linked to original sources
PubMed1985

Catalase and superoxide dismutase activities in virulent and nonvirulent Staphylococcus aureus isolates.

Catalase and superoxide dismutase (SOD) activities of virulent and nonvirulent isolates of Staphylococcus aureus were compared. The mean value of catalase activity for intact cell suspensions was 2,773 +/- 1,049 Kat f units (Kat f is defined as the ratio of the velocity constant of catalase at 0 min to the protein content in grams per milliliter); that of nonvirulent isolates was 154 +/- 92 Kat f units. The mean value of the catalase activities for lysates of virulent isolates was 260 +/- 120 Kat f units, and that of nonvirulent isolates was 31 +/- 19 Kat f units. Catalase levels in intact cells as well as in cell lysates were significantly different for virulent than for nonvirulent S. aureus isolates (P less than 0.001). The mean value of SOD activities was 20.85 +/- 11.48 U (1 U is defined as the amount of SOD required to inhibit the rate of reduction of cytochrome c by 50%) for virulent cell lysates, compared with a mean of 5.39 +/- 2.89 U for nonvirulent cell lysates. The SOD levels in virulent and nonvirulent isolates were significantly different (P less than 0.001). The virulence of the S. aureus isolates was determined by comparing weight gains of neonatal mice injected with virulent or nonvirulent strains. The percent weight gain of neonatal mice injected with virulent isolates was significantly lower than that of those injected with nonvirulent isolates.

Animals↗
PubMed1984

Atypical herpes simplex (HSV) infection in a patient with Hodgkin's disease.

An atypical presentation of herpes simplex virus type 1 (HSV-I) in the form of nodular tongue lesions was documented by histologic and immunohistochemical studies in a patient with advanced Hodgkin's disease. This represents yet another manifestation of HSV-I in the immunocompromised host and further emphasizes awareness of the oral complications of cancer chemotherapy.

Adult↗
PubMed1984

Effect of dietary protein concentration on rat-liver S9 bioactivation of 7,12-dimethylbenz[a]anthracene in the Salmonella/microsome assay.

These studies describe the influence of dietary protein concentration on the ability of rat-liver postmitochondrial fraction (S9) to mediate 7,12-dimethylbenz[a]anthracene (DMBA) mutagenicity in the Ames Salmonella/microsome assay. A negative correlation was observed between dietary protein content and DMBA mutagenicity. The effect of protein was not dependent on the quantity of Aroclor used for induction. Dietary protein did not influence the mutagenicity of DMBA when isolated microsomes were used in place of S9.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1984

Immunologic methods in cytology: definitive diagnosis of non-Hodgkin's lymphomas using immunologic markers for T- and B-cells.

The cytologic diagnosis of malignant lymphoma can be extremely difficult because the cytologic features of the malignant cells in small cell and mixed small and large cell lymphomas may be indistinguishable from those of reactive lymphoid cells. In addition, large cell lymphoma can be difficult to distinguish from undifferentiated carcinoma in cytologic specimens. Using the avidin-biotin immunoperoxidase technic and antibodies to the B-cell markers alpha, gamma, and mu heavy chains and kappa and lambda light chains, to the T-cell markers Leu-1, Leu-2a, and Leu-3a, to the lymphoid marker T200, to TdT, and to Leu-M3, the authors studied 35 cytologic specimens including pleural, cerebrospinal, and ascites fluids and fine-needle aspirations. Immunologic staining allowed them to make a definitive diagnosis of lymphoma or reactive effusion in every case studied and resulted in a significant modification of the morphologic diagnosis in over 50% of cases. In 16 cases the lymphoid cells were monoclonal B-cells: ten expressing IgM kappa; four expressing IgM lambda; one expressing IgA kappa; and one expressing kappa without demonstrable heavy chain expression. Although there are no good markers of monoclonality for T-cells, the authors were able to make a positive diagnosis in two cases of T-cell lymphoid malignancies by the expression of an aberrant phenotype on the malignant cells. The expression of TdT confirmed the diagnosis in one case of common ALL and one lymphoblastic lymphoma. In a patient with a "null cell" large cell lymphoma, the expression of T200 on the malignant cells ruled out the possibility of carcinoma. In 15 cases the marker studies indicated a reactive lymphoid proliferation. The authors conclude that immunologic markers are very useful in the cytologic diagnosis of lymphoma.

Adolescent↗
PubMed1984

Sedimentation analysis of von Willebrand and factor VIIIC protein using partition cells in the analytical ultracentrifuge.

Sedimentation analysis of factor VIII complex was performed in the analytical ultracentrifuge using partition cells. This method allowed for the calculation of three different sedimentation coefficients from each run: one based on ristocetin agglutination activity for von Willebrand protein, SWF; one based on coagulant activity for factor VIIIC, SVIIIC; and one based on the schlieren or adsorption data for protein concentration, Sconc. In most cases, there was no agreement between the three values calculated from the same run, indicating a heterogeneous system. The calculated functional sedimentation coefficients give values that require the molecules to be highly asymmetric to be consistent with a glycoprotein of high molecular weight, which is in agreement with results observed in electron microscope studies. The dissociation of VIIIC into a smaller form can be demonstrated by this method. Determination of the three sedimentation coefficients in a series of fractions from gel filtration indicates a uniform size for the VIIIC activity but not for the WF activity. These observations are in agreement with the concept of a copolymer between WF and VIIIC and also with the concept of separate polymers for the two activities.

Antigens↗
PubMed1983

"Low grade" mucoepidermoid carcinoma of the bronchus with "high grade" biological behavior.

A case of mucoepidermoid carcinoma of the bronchus with low grade histologic features exhibited an aggressive biological behavior. All gross, microscopic, and ultrastructural features were those of a morphologically low grade mucoepidermoid carcinoma. Grossly, the lesion was an exophytic endobronchial mass; microscopically, it contained sheets of monomorphic cells with well-formed mucus glands, no mitoses, and no necrosis; and ultrastructurally, it consisted of numerous goblet cells and mitochondria- and glycogen-rich cells with well-formed microvilli. However, the patient developed widespread metastases to skin, subcutaneous tissue, femur, vertebral column, and pericardium and died two months after the primary endobronchial tumor was excised. The metastases, like the primary tumor, had the appearance of "low grade" mucoepidermoid carcinoma. Explants of the original tumor grown in nude mice for three months showed persistence of the low-grade morphologic pattern. Although metastases are known to occur frequently from high-grade lesions, widespread metastases from histologically low-grade lesions have not previously been reported. Low-grade histologic features of mucoepidermoid carcinoma are not necessarily then indicative of low-grade biological behavior.

Adult↗
PubMed1983

Alveolar bone necrosis and tooth loss. a rare complication associated with herpes zoster infection of the fifth cranial nerve.

Eleven case reports involving herpes zoster infection associated with alveolar bone necrosis and tooth loss were reviewed in order to develop a patient profile for this rare combination of physical findings. The clinical course of a 56-year-old white woman with herpes zoster infection of the fifth cranial nerve and related alveolar bone necrosis, tooth loss, and oroantral fistula development is reported. The etiology and management of herpes zoster infection associated with destructive oral sequelae are discussed.

Alveolar Process↗
PubMed1982

Small-cell osteosarcoma.

Six cases of small-cell osteosarcoma, a tumor that resembles Ewing's sarcoma but produces osteoid matrix, are presented. The patients were young (6-31 years of age) and presented with symptoms of pain and/or swelling of 1-10 months duration. The lesions demonstrated a wide variation in radiographic appearance. Histologically, the tumors were composed of small, round cells that produced variable amounts of osteoid. In three cases chondroid was also present. Two of the six patients were treated with surgery alone and four received radiation and either single- or multiple-agent adjuvant chemotherapy. The two patients who received radiation and multiple-agent adjuvant chemotherapy have no evidence of disease at four and ten years after diagnosis. Recognition of this tumor as distinct from Ewing's sarcoma and from other forms of osteosarcoma is important to determine the incidence, clinical features, and optimal therapy for this tumor.

Adolescent↗
PubMed1982

The effects of dietary selenium on the biotransformation of 7,21-dimethylbenz[a]anthracene.

The influence of dietary selenium on the mutagenic activation of 7,12-dimethylbenz[a]anthracene (DMBA) by rat liver S9 was studied using the Ames test. Rats received supplemental selenium, as sodium selenite, in the drinking water or in the diet. All rats additionally received 0, 20, 50, 100, or 500 mg Aroclor 1254 per kg body weight. Revertant counts decreased 72 and 31% at the 20- and 100-mg/kg induction levels, respectively, with S9 preparations from rats given selenium supplementation, compared to controls. No significant effects of selenium on S9 preparations was observed in rats treated with 500 mg/kg Aroclor. Preparations of S9 from rats receiving 2.5 ppm Se in their diet produced 46, 84 and 70% less revertants than controls at the 20-, 50- and 100-mg/kg induction levels. Increasing the selenium concentration in the diet to 5 ppm reduced the revertant counts by 71, 68 and 65%, at the 20-, 50- and 100-mg/kg induction level of Aroclor, respectively. Dietary selenium supplementation was shown to decrease the mutagenic activation of DMBA by liver microsomes. These studies indicate that in vivo selenium supplementation may reduce susceptibility to the action of various carcinogens.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1982

Effect of free-radical scavengers on enumeration of thermally stressed cells of Staphylococcus aureus MF-31.

Exposure of crude cell lysates of Staphylococcus aureus MF-31 to 5 or 10 mM hydrogen peroxide resulted in a linear decrease in superoxide dismutase activity. Approximately 13% of the superoxide dismutase activity was lost after 16 min. Thermally stressed and nonstressed cells were exposed to a photochemically generated exogenous flux of superoxide radicals (O2.-). The death of thermally stressed cells was linear with time. Addition of superoxide dismutase or catalase to the O2.- generating system resulted in protection of thermally stressed and nonstressed cells, with the protective effect being greater for thermally stressed cells. Incorporation of O2-, hydroxyl radical, or singlet oxygen scavengers or antioxidants to tryptic soy agar containing 7.5% NaCl did not increase the enumeration of thermally stressed cells.

Catalase↗
PubMed1982

Interstitial pulmonary infiltrate following combined therapy for esophageal carcinoma.

Seven patients with squamous cell carcinoma of the esophagus received radiation therapy in twice weekly 400 rad fractions over five weeks followed by esophagectomy. Four of these patients developed severe interstitial pulmonary infiltrates and died of pulmonary insufficiency 18-50 days after surgery. In three of these patients the infiltrates were detected within 24 hours of surgery while the infiltrate was not present until the eighth postoperative day in the fourth patient. Postmortem examination revealed widespread dilatation of interstitial and subpleural lymphatics. It is postulated that the combination of large fraction radiation therapy followed by extensive surgery resulted in lymphatic obstruction.

Aged↗
PubMed1981

Antimutagenic effect of selenium on acridine orange and 7,12-dimethylbenz[alpha]anthracene in the Ames Salmonella/microsomal system.

The antimutagenic effects of selenium as sodium selenite were investigated using the Ames Salmonella/microsome mutagenicity test. The compounds examined were acridine orange and 7,12-dimethylbenz[alpha]anthracene. Selenium (22 ppm) reduced the number of histidine revertants caused by 20 microgram acridine orange and 20 microgram 7,12-dimethylbenz[alpha]anthracene by 52 and 74%, respectively. Increasing the quantity of selenium added to the plates further suppressed the mutagenicity of the test compounds. The antimutagenic effects of selenium cannot be explained by lethality of Salmonella typhimurium.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1981

Superoxide dismutase activity in thermally stressed Staphylococcus aureus.

The effects of heat and NaCl on the activity of superoxide dismutase from Staphylococcus aureus were examined. A linear decrease in superoxide dismutase activity occurred when S. aureus MF-31 cells were thermally stressed for 90 min at 52% C in 100 mM potassium phosphate buffer (pH 7.2). After 20 min of heating, only 5% of the superoxide dismutase activity was lost. Heating for 60, 90 and 120 min resulted in decreases of approximately 10, 22, and 68%, respectively. The rates of thermal inactivation of superoxide dismutase from S. aureus strains 196E and 210 were similar and slightly greater than those of strains MF-31, S-6, and 181. The addition of NaCl before or after heating resulted in increased losses of superoxide dismutase activity.

Hot Temperature↗
PubMed1981

Superoxide dismutase activity during recovery of thermally stressed Staphylococcus aureus MF-31.

Superoxide dismutase (SOD) activity was determined during the growth cycle of unheated and heat-injured cells of Staphylococcus aureus MF-31. SOd activity levels dropped in unheated cells during the lag phase, increased during logarithmic phase, and became constant in the stationary phase. Cells which were sublethally heated (52 degrees c, 20 min) in 100 mM phosphate buffer and subsequently allowed to recover in tryptic soy broth demonstrated an 85% decrease in SOD activity upon inoculation into recovery medium. As the injured cells repaired the heat-induced lesions and entered logarithmic growth, SOD levels rapidly increased. Heat-injured cells allowed to recover in tryptic soy broth plus 10% NaCl showed similar decreases in SOD activity levels. However, no subsequent increase was observed when specific activity was calculated based on milligrams of protein.

Culture Media↗
PubMed1981

Combined effect of acetate and reduced water activity in survival of Salmonella typhimurium 7136.

Whereas Salmonella typhimurium 7136 will not grow at reduced water activity (aw), it was survival in such items as intermediate-moisture foods is of interest. Initial studies demonstrated that the addition of 0.3 M acetate (pH 4.7) to glycerol-Trypticase soy broth (BBL Microbiology Systems) solutions (aw 0.86) reduced the viability of S. typhimurium cells. The extent of death of cells exposed to reduced aw was increased by decreasing the pH or increasing the concentration of acetate. Acidification of glycerol-Trypticase soy broth reduced the D40 degrees C value exhibited by cells exposed to a range of aw solutions (0.65 to 0.92). Acetate appeared to affect survival more dramatically as aw values approached the minimum growth limit. Acidification with acetate also reduced cell survival in a variety of humectant solutions with an aw of 0.86 (glycerol, dextrose, and NaCl).

Acetates↗
PubMed1980

Demonstration of a large molecular weight variant of the gamma chain of normal human plasma fibrinogen.

A previously undescribed gamma chain variant of human fibrinogen has been identified by application of a sensitive sodium dodecyl sulfate-polyacrylamide gradient gel electrophoretic technique to separate the polypeptide chains. This variant, called gamma B, clots and cross-links as well as the major species (gamma A), is similarly degraded by plasmin, and has a molecular weight of 53,100 as compared to 50,100 for gamma A. Cross-linked dimers of Mr = 100,100 and 108,500 are identified after action of thrombin and Factor XIIIa, suggesting the formation of gamma A-gamma A and gamma B-gamma B dimers rather than gamma A-gamma B hybrid species. The gamma B chain dimers represent 16% of the total cross-linked gamma chain forms. Two early plasmic derivatives of gamma A and gamma B chains have been demonstrated to have lost fragments of Mr = approximately 4,000 and 5,000 without loss of 5-dimethylaminonaphthalene-1-sulfonyl cadaverine fluorescence. Since the difference in molecular weight of gamma A and gamma B chains is maintained during plasmic degradation of both monomer and dimeric fluorescent forms, this suggests that the additional sequence of amino acids in gamma B is located at or near the COOH-terminal end of this polypeptide chain.

Electrophoresis, Polyacrylamide Gel↗