Protein kinase C increases the activity of the polyoma virus middle T antigen-associated phosphatidylinositol kinase

Exposure of polyoma virus-transformed fibroblasts to the protein kinase C-stimulating phorbol ester 12-O-tetradecanoyl phorbol-13-acetate (TPA) is known to increase the transforming potential of the virus's middle T antigen. Here it is shown that this TPA treatment also stimulates an 85 kDa phosphatidylinositol kinase associated with the middle T antigen. Since activation of this kinase is known to be necessary, although not by itself sufficient for the transformation of cells by polyoma virus, bursts of protein kinase C activity, triggered by TPA or various cellular receptors, might enhance the oncogenicity of polyoma virus by stimulating this middle T antigen-associated phosphatidylinositol kinase.     

Evidence for two waves of induction of DNA enzymes in stimulated human lymphocytes

The stimulation of human lymphocytes with phytohaemoagglutinin induces the appearance or increase of several enzymes of DNA metabolism [Pedrini etal., Biochem. Biophys. Res. Comm., 47:1221(1972)]. With long times of stimulation, two phenomena are observed; an increase in the levels of DNA polymerase, of a DNase acting on single-stranded DNA, and of an endonuclease, occurring between the third and fourth day, in parallel with a wave of DNA synthesis;a second wave of increase of the same enzymes and of DNA ligase,occurring between the fifth and eight day when the DNA replication rate, as measured by thymidine-pulses, has decreased to values close to the background.     

Polyomavirus transforms rat F111 and mouse NIH 3T3 cells by different mechanisms.

Polyomavirus middle tumor antigen (mT) was expressed in a line of mouse NIH 3T3 cells under control of the dexamethasone-regulatable mouse mammary tumor virus promotor. Contrary to rat F111 cells which were rendered anchorage independent by mT expression alone (L. Raptis, H. Lamfrom, and T.L. Benjamin, Mol. Cell. Biol. 5:2476-2487, 1985), mT-producing NIH 3T3 cells were unable to grow in agar even after full mT induction. The mT:pp60c-src-associated phosphatidylinositol kinase was activated in these cells to a degree similar to that in fully transformed cells expressing the small and large T antigens, in addition to mT. We therefore propose that the stimulation of this phosphatidylinositol kinase, although apparently necessary, is not sufficient for transformation of NIH 3T3 cells by polyomavirus.     

Purification and characterization of the high molecular weight microtubule associated proteins from neonatal rat brain

The changes in the levels of microtubule-associated proteins (MAPs) during advanced embryonic stages, neonatal and adult organisms reflect the importance of these cytoskeletal proteins in relation to the morphogenesis of the central nervous system. MAP-1B is found in prenatal brains and it appears to have the highests levels in neonatal rat brains, being a developmentally-regulated protein. In this research, a fast procedure to isolate MAP-1B, as well as MAP-2 and MAP-3 from neonatal rat brains was designed, based on the differential capacity of poly L-aspartic acid to release MAPs during temperature-dependent cycles of microtubule assembly in the absence of taxol. The high molecular weight MAP-1B was recovered in the warm supernatants after microtubular protein polymerization in the presence of low concentrations of polyaspartic acid. Instead, MAP-2 and a 180 kDa protein with characteristics of MAP-3 remained associated to the polymer after the assembly. Further purification of MAP-1B was attained after phosphocellulose chromatography. Isolation of MAP-2 isoforms together with MAP-3 was achieved on the basis of their selective interactions with calmodulin-agarose affinity columns. In addition, MAP-2 and MAP-3 were also purified on the basis of their capacities to interact with the tubulin peptide -II (422–434) derivatized on an Affigel matrix. However, MAP-1B did not interact with the -II tubulin fragment, but it showed interaction with the Affigel-conjugated -I (431–444) tubulin peptide. The different MAPs componentes were characterized by western blots using specific monoclonal antibodies. A salient feature of neonatal rat brain MAP-3 was its interactions with site-directed antibodies that recognize binding epitopes on the repetitive sequences of tau and MAP-2. However, these site-specific antibodies did not interact with MAP-1B from the neonatal rat brain tissue.Abbreviations PAA poly (L-aspartic acid) - HMW-MAPs high molecular weight microtubule associated proteins     

Characterization of Inorganic Biocarriers That Moderate System Upsets during Fixed-Film Biotreatment Processes

Inorganic matrices were developed for fixed-film bioreactors affording protection to microorganisms and preventing loss of bioreactor productivity during system upsets. These biocarriers, designated Type-Z, contain ion-exchange properties and possess high porosity and a high level of surface area, which provide a suitable medium for microbial colonization. Viable cell populations of 10⁹/g were attainable, and scanning electron micrographs revealed extensive external colonization and moderate internal colonization with aerobic microorganisms. Laboratory-scale bioreactors were established with various biocarriers and colonized with Pseudomonas aeruginosa, and comparative studies were performed. The data indicated that bioreactors containing the Type-Z biocarriers were more proficient at removing phenol (1,000 ppm) than bioreactors established with Flexirings (plastic) and Celite R635 (diatomaceous earth) biocarriers. More significantly, these biocarriers were shown to moderate system upsets that affect operation of full-scale biotreatment processes. For example, subjecting the Type-Z bioreactor to an influent phenol feed at pH 2 for periods of 24 h did not decrease the effluent pH or reactor performance. In contrast, bioreactors containing either Celite or Flexirings demonstrated an effluent pH drop to ~2.5 and a reduction in reactor performance by 75 to 82%. The Celite reactor recovered after 5 days, whereas the bioreactors containing Flexirings did not recover. Similar advantages were noted during either nutrient or oxygen deprivation experiments as well as alkali and organic system shocks. The available data suggest that Type-Z biocarriers represent an immobilization medium that provides an amenable environment for microbial growth and has the potential for improving the reliability of fixed-film biotreatment processes.     

Yeasts from Marine and Estuarine Waters with Different Levels of Pollution in the State of Rio de Janeiro, Brazil

Yeast counts were made at 24 marine and estuarine sites in the vicinity of Rio de Janeiro, Brazil. Mean salinities of estuarine sites ranged from 14.2 to 27.4‰, and mean temperatures ranged from 25 to 28°C. Total coliform counts varied from 80% above 100,000 colony-forming units (CFU)/100 ml at heavily polluted sites to 100% below 100 CFU/100 ml at unpolluted sites. Total yeast counts above 100 CFU/100 ml were typical of heavily and moderately polluted water but atypical of lightly polluted and unpolluted water. Mean total yeast counts were 2,880 CFU/100 ml for heavily polluted sites, 202 CFU/100 ml for moderately polluted sites, and 3 CFU/100 ml for lightly polluted and unpolluted sites. Total yeast counts had a positive response to increased pollution levels, and Candida krusei and phenotypically similar yeasts as a group were prevalent in polluted estuarine water but rare in unpolluted seawater. The 549 strains of yeasts and yeast-like organisms isolated were grouped into 67 species, of which the 21 most prevalent made up 86% of the total yeast population. The prevalent genera in the polluted estuary were Candida, Rhodotorula, Torulopsis, Hanseniaspora, Debaryomyces, and Trichosporon.     

Extended somatostatin treatment of a patient with bleeding ulcer.

The results of a 67 hour cyclic somatostatin continuous infusion in a patient with a bleeding ulcer are reported. The subject was a 65 year old male with very heavy gastrointestinal bleeding on the 9th postoperative day following a high BI-resection. Endoscopy revealed the bleeding to be caused by two residual ulcers in the area of the anastomosis. Somatostatin treatment led to an immediate cessation of the bleeding after 1 hour. Gastric secretion as well as gastrin, insulin and growth hormone levels were significantly inhibited by somatostatin. Endoscopy at the end of the treatment period showed two ulcers in the process of healing. The raised blood glucose levels caused by somatostatin were easily controlled with max. 14 IU cristalline insulin daily. Except for dryness in the mouth, no adverse side effects were apparent. There was no evidence from laboratory investigations of hemostatic defects or bleeding tendency in the patient.     

Increased kynurenine-to-tryptophan ratio in the serum of patients infected with SARS-CoV2: An observational cohort study.

Immune dysregulation is a hallmark of patients infected by SARS-CoV2 and the balance between immune reactivity and tolerance is a key determinant of all stages of infection, including the excessive inflammatory state causing the acute respiratory distress syndrome. The kynurenine pathway (KP) of tryptophan (Trp) metabolism is activated by pro-inflammatory cytokines and drives mechanisms of immune tolerance. We examined the state of activation of the KP by measuring the Kyn:Trp ratio in the serum of healthy subjects (n = 239), and SARS-CoV2-negative (n = 305) and -positive patients (n = 89). Patients were recruited at the Emergency Room of St. Andrea Hospital (Rome, Italy). Kyn and Trp serum levels were assessed by HPLC/MS-MS. Compared to healthy controls, both SARS-CoV2-negative and -positive patients showed an increase in the Kyn:Trp ratio. The increase was larger in SARS-CoV2-positive patients, with a significant difference between SARS-CoV2-positive and -negative patients. In addition, the increase was more prominent in males, and positively correlated with age and severity of SARS-CoV2 infection, categorized as follows: 1 = no need for intensive care unit (ICU); 2 ≤ 3 weeks spent in ICU; 3 ≥ 3 weeks spent in ICU; and 4 = death. The highest Kyn:Trp values were found in SARS-CoV2-positive patients with severe lymphopenia. These findings suggest that the Kyn:Trp ratio reflects the level of inflammation associated with SARS-CoV2 infection, and, therefore, might represent a valuable biomarker for therapeutic intervention.