Search PubMed⌕ Search

Biomedical subjects

J J Perry

Publications and source records attributed to J J Perry.

At least 37 records · Page 2Linked to original sources
PubMed1994

Dehalogenation by Mycobacterium vaccae JOB-5: role of the propane monooxygenase.

Mycobacterium vaccae JOB-5 has an inducible propane monooxygenase that has been implicated in the catabolism of most major groundwater pollutants including trichloroethylene. Propane-grown cells are also induced for the dehalogenation of 1-chlorobutane and other chloroalkanes. 1-Chlorobutane is oxidized to 2-butanol, indicating that subterminal oxidation of 1-chlorobutane resulted in a concomitant release of the chloride. Nonproliferating suspensions of M. vaccae induced for the propane monooxygenase can dehalogenate a variety of chlorinated hydrocarbons including monochlorinated alcohols, dichlorinated short chain alkanes, and several multiple-substituted compounds including trichloroethylene. The results indicate that M. vaccae JOB-5 has a monooxygenase of broad specificity that can dehalogenate an array of halogenated hydrocarbons.

Biodegradation, Environmental↗
PubMed1994

Management of disseminated disease in the patient with bladder cancer.

Advanced transitional cell carcinoma of the bladder is a chemotherapy-sensitive neoplasm. Several single agents demonstrate substantial activity, and combination chemotherapy produces responses in the majority of patients treated. The benefits and toxicities associated with the most widely used combination regimens are discussed. Other topics reviewed include the use of colony-stimulating factor support for chemotherapy, adjunctive surgical therapy, and newer cytotoxic regimens.

Antineoplastic Agents↗
PubMed1993

Coincidental polycythemia vera and multiple myeloma: case report and review.

Polycythemia vera (PCV) and multiple myeloma are both clonal disorders of hematopoietic stem cells. The simultaneous occurrence of these diseases in an individual patient is rare. A case of synchronous PCV and smoldering myeloma is presented and the literature is reviewed. The issues of clinical importance in this unusual case include the mechanisms of anemia in multiple myeloma, the difficulty in using anemia as a parameter on which to base the initiation of therapy for myeloma, and the risks of treatment-induced leukemia and myelodysplasia.

Aged↗
PubMed1993

Biodegradation and biotransformation of groundwater pollutant mixtures by Mycobacterium vaccae.

Mycobacterium vaccae can catabolize a number of major groundwater pollutants. When added singly, acetone, cyclohexane, styrene, benzene, ethylbenzene, propylbenzene, dioxane, and 1,2-dichloroethylene can be catabolized by M. vaccae. Catabolism of a number of these chemicals was monitored by gas-chromatographic analysis. Gas-chromatographic analysis indicated that the products of benzene degradation are phenol and hydroquinone. The products of chlorobenzene and ethylbenzene degradation are 4-chlorophenol and 4-ethylphenol. The extent that some compounds were catabolized when present as mixtures was also investigated. When toluene and benzene were present concomitantly, toluene was catabolized and benzene oxidation was delayed. Although toluene promoted the degradation of styrene, a lower rate of toluene degradation occurred when styrene was present. Both 4-chlorophenol and 4-ethylphenol had an antagonistic effect on the ability of M. vaccae to degrade other aromatic compounds. Studies with [14C]benzene indicated that M. vaccae can mineralize small amounts of this compound. These results suggest that components in mixtures may have a positive or a negative effect on the rates of biodegradation of other pollutants.

Acetone↗
PubMed1992

Isolated central nervous system relapse of testicular cancer.

Central nervous system involvement with testicular cancer usually occurs with advanced systemic disease. Isolated CNS disease at relapse is rare. We report a patient who developed a solitary brain metastasis with no other systemic disease after having achieved a complete response to frontline therapy. After combined modality therapy for the CNS disease, the patient has remained disease-free for more than 3 years. The literature regarding brain metastases in relapsed testicular cancer is reviewed, including nine cases of isolated brain metastases. The CNS can be a "sanctuary" site for testicular cancer, and in the unusual subset of patients with isolated brain relapse, long-term remission is possible with aggressive therapy.

Adult↗
PubMed1992

Characterization of bacteriocins from two strains of Bacillus thermoleovorans, a thermophilic hydrocarbon-utilizing species.

Bacillus thermoleovorans S-II and B. thermoleovorans NR-9 produce bacteriocins, and these bacteriocins are designated thermoleovorin-S2 and thermoleovorin-N9, respectively. The bacteriocins are effective against all but the producing strain of B. thermoleovorans, as well as being effective against Salmonella typhimurium, Branhamella catarrhalis, Streptococcus faecalis, and Thermus aquaticus. Thermoleovorins are produced during log-phase growth and are inhibitory to actively growing cells. The bacteriocins are proteinaceous in nature, being sensitive to selected proteases (protease type XI and pepsin). They are stable at pHs of 3 to 10. Thermoleovorin-S2 was more thermostable than thermoleovorin-N9 at 70 and 80 degrees C. Thermoleovorins-S2 and -N9 apparently act by binding to the susceptible organisms, resulting in lysis of the cell. Thermoleovorins-S2 has an estimated M(r) of 42,000, while thermoleovorin-N9 has a M(r) of 36,000.

Bacillus↗
PubMed1990

Small cell lung cancer: staging with MR imaging.

Small cell lung cancer is an aggressive neoplasm; metastases are detected in two-thirds of patients at diagnosis with use of conventional staging, which includes bilateral bone marrow biopsy, bone scintigraphy, and computed tomography (CT) of the head and abdomen. In 25 patients, small cell lung cancer was staged prospectively with both conventional staging and a magnetic resonance (MR) imaging protocol that included 1.5-T MR imaging of the pelvis, abdomen, spine, and brain. According to conventional staging, 14 patients had extensive disease and 11 patients had limited disease; according to staging with MR, 19 patients had extensive disease and six had limited disease. All metastatic disease sites seen with conventional staging were identified on MR images. MR images showed additional metastatic involvement in bone (four patients) and liver (three patients) not detected at conventional staging. A low-attenuation hepatic lesion on a CT scan was identified as a hemangioma on MR images. These preliminary data suggest that small cell lung cancer may be accurately staged with use of a single MR imaging study.

Adrenal Glands↗
PubMed1990

von Willebrand's disease.

Patients with a history of epistaxis, menorrhagia or excessive bleeding after dental or surgical procedures may have von Willebrand's disease. Although screening coagulation tests may be normal, many patients with this disease will have excessive bleeding after surgical procedures if the disorder has not been recognized and appropriately treated. Patients with von Willebrand's disease may be treated with a medication that stimulates an increase in von Willebrand's factor, allowing them to avoid the need for blood product support.

Adolescent↗
PubMed1987

Chlorinated fatty acid distribution in Mycobacterium convolutum phospholipids after growth on 1-chlorohexadecane.

The composition of phospholipids from Mycobacterium convolutum R22 was determined after growth at two temperatures (20 and 30 degrees C) with 1-chlorohexadecane as the substrate. Comparisons were made with the phospholipids of cells grown on n-hexadecane. Phosphatidylinositolmannosides and phosphatidylethanolamine (PE) were the major phospholipids in n-hexadecane-grown cells. In 1-chlorohexadecane-grown cells, phosphatidylinositolmannosides were approximately half of the total phospholipids, with lesser amounts of PE and cardiolipin (CL). The relative level of PE was greater at 20 degrees C (versus that at 30 degrees C) after growth on either substrate. A determination was made of structure and positional distribution of constituent fatty acid in both CL and PE. The relative amount of unsaturated fatty acid was higher at 20 degrees C. There were two C16:1 fatty acids (C16:1 delta 9 and C16:1 delta 11), and these had positional preferences in both CL and PE. The positional sites of chlorinated fatty acids differed in both CL and PE at the two temperatures. The results confirm that microorganisms can specifically distribute chlorinated fatty acids into cellular phospholipids.

Alkanes↗
PubMed1986

Effect of methyl viologen and oxygen concentration on thermophilic bacteria.

The level of superoxide dismutase, catalase, and peroxidase was determined in obligately thermophilic bacteria after growth either in the presence of methyl viologen (paraquat) or exposed to an increased atmospheric oxygen concentration. In general, the superoxide dismutase level in these organisms was not altered by paraquat addition and had a varied response to oxygenation. Incorporation of paraquat in the growth medium resulted in minimally three-fold higher levels of catalase. The peroxidase level varied as a response to oxygen stress whereas cellular catalase levels were generally higher.

Bacteria↗
PubMed1986

Characterization of a manganese-containing catalase from the obligate thermophile Thermoleophilum album.

A manganese-containing catalase has been characterized from Thermoleophilum album NM, a gram-negative aerobic bacterium obligate for thermophily and n-alkane substrates. The level of catalase in cells was increased about ninefold by growth in the presence of paraquat (2.5 microM), a superoxide-generating toxicant. Superoxide dismutase levels were unaffected by this compound. The enzyme was purified from cultures grown in the presence of paraquat to greater than 95% homogeneity and had an Mr of 141,000. The enzyme was composed of four subunits, and each had an Mr of 34,000. There were 1.4 +/- 0.4 atoms of manganese present per subunit. The catalase had a Km for hydrogen peroxide of 15 mM and a Vmax of 11 mM/mg. Peroxidase activity, as measured with p-phenylenediamine, copurified with the catalase. Inhibitors of heme-catalase were weak inhibitors of the T. album enzyme. The optimum pH for catalase activity was 8 to 9. The enzyme was stable from pH 6.5 to 11 and retained activity at assay temperatures from 25 to 80 degrees C. The catalase was stable for 24 h of incubation at 60 degrees C.

Catalase↗
PubMed1985

Paraquat toxicity and effect of hydrogen peroxide on thermophilic bacteria.

Paraquat (PQ++) increased cyanide-resistant univalent respiration in cell suspensions of five strains of obligately thermophilic bacteria. PQ++ was reduced by an NADH: or NADPH:paraquat diaphorase and selectivity for NADH, NADPH, or both electron donors varied among the thermophiles. Superoxide anion production that was dependent on the presence of PQ++ was shown by following the superoxide dismutase-inhibitable reduction of cytochrome c. In addition, the PQ++-dependent formation of hydrogen peroxide from superoxide anion was evident in two of the thermophilic strains. Catalase synthesis was induced by adding hydrogen peroxide to the growth medium of the thermophiles. The induction of catalase to eliminate hydrogen peroxide appears to be an important response of these thermophilic bacteria to oxygen toxicity.

Catalase↗
PubMed1985

Purification and characterization of the secondary alcohol dehydrogenase from propane-utilizing Mycobacterium vaccae strain JOB-5.

Mycobacterium vaccae strain JOB-5 cultured in the presence of propane contained an inducible secondary alcohol dehydrogenase. The enzyme was purified 198-fold using DEAE-cellulose, omega-aminopentyl agarose and NAD-agarose chromatography. The Mr of the enzyme was approximately 136000, with subunits of Mr 37000. The pH optimum for the reaction oxidizing propan-2-ol to propanone was 10-10.5 while the optimum for the reverse reaction was 7.5-8.5. The isoelectric point was 4.9. NAD but not NADP could serve as electron acceptor. The apparent Km values for propan-2-ol and NAD were 4.9 X 10(-5)M and 2.8 X 10(-4)M, respectively. The enzyme was inhibited by thiol reagents and metal chelators. It appears to play an essential role in the metabolism of propane by this bacterium.

Alcohol Oxidoreductases↗
PubMed1985

Oxygen defense systems in obligately thermophilic bacteria.

Ten strains of Gram-negative, aerobic, obligately thermophilic bacteria were examined for their response to oxygen toxicity by comparing static with shaken cultures. All of the organisms tested had measurable levels of superoxide dismutase, catalase, and peroxidase. Aeration generally did not result in an increased level of superoxide dismutase in any of the thermophiles. Aeration of organisms obligate for n-alkane substrate caused an increase in cellular peroxidase levels and a corresponding decrease in catalase. The thermophiles that grew on either n-alkanes or complex media did not grow on the hydrocarbon in aerated culture but on a complex medium, aeration effected an increased level of catalase. With the exception of a pink-pigmented thermophile which, when aerated, did not have an increased level of the three oxygen defense enzymes, most of the thermophiles surveyed had an increased level of catalase or peroxidase when exposed to increased oxygen tension. The activity of the enzymes was determined at temperatures from 25 to 65 degrees C and the former temperature was satisfactory for these experiments.

Alkanes↗
PubMed1984

Assimilation of chlorinated alkanes by hydrocarbon-utilizing fungi.

The fatty acid compositions of two filamentous fungi (Cunninghamella elegans and Penicillium zonatum) and a yeast (Candida lipolytica) were determined after the organisms were grown on 1-chlorohexadecane or 1-chlorooctadecane. These organisms utilized the chlorinated alkanes as sole sources of carbon and energy. Analyses of the fatty acids present after growth on the chlorinated alkanes indicated that 60 to 70% of the total fatty acids in C. elegans were chlorinated. Approximately 50% of the fatty acids in C. lipolytica were also chlorinated. P. zonatum contained 20% 1-chlorohexadecanoic acid after growth on either substrate but did not incorporate C18 chlorinated fatty acids.

Alkanes↗
PubMed1984

Purification and characterization of the amine dehydrogenase from a facultative methylotroph.

Strain RA-6 is a pink-pigmented organism which can grow on a variety of substrates including methylamine. It can utilize methylamine as sole source of carbon via an isocitrate lyase negative serine pathway. Methylamine grown cells contain an inducible primary amine dehydrogenase [primary amine: (acceptor) oxidoreductase (deaminating)] which is not present in succinate grown cells. The amine dehydrogenase was purified to over 90% homogeneity. It is an acidic protein (isoelectric point of 5.37) with a molecular weight of 118,000 containing subunits with approximate molecular weights of 16,500 and 46,000. It is active on an array of primary terminal amines and is strongly inhibited by carbonyl reagents. Cytochrome c or artificial electron acceptors are required for activity; neither NAD nor NADP can serve as primary electron acceptor.

Methylamines↗
PubMed1983

Rectal syphilis mimicking histiocytic lymphoma.

Homosexuality is being recognized with increasing frequency in the United States, and the physician must be knowledgeable of the presentations of venereal infection in this population. A 23-year-old man who denied homosexuality presented with a rectal mass and diffuse adenopathy. Biopsy of the mass was interpreted as histiocytic lymphoma. Subsequent serology had positive results for syphilis. Further questioning revealed a history of anorectal intercourse, and special stains of the mass revealed spirochetes. Syphilis must be considered in any young patient presenting with a rectal mass, regardless of the biopsy histologic characteristics or sexual history.

Adult↗