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M J Wolin

Publications and source records attributed to M J Wolin.

97 records · Page 6Linked to original sources
PubMed1966

Effect of pH on population and fermentation in a continuously cultured rumen ecosystem.

The effect of pH on rumen fermentation and microbial population was studied in a continuously cultured rumen ecosystem. A marked decrease in the production of volatile fatty acids and methane from alfalfa hay occurred when the cultures were maintained at pH values below 6.0. The decrease in acetate and methane production was greater than that of propionate production. The culture maintained at pH 6.7 contained the types of bacteria often found in high concentration in the rumen, whereas the culture maintained at pH 5.0 had a high percentage of bacteria which could not be identified with the major rumen bacteria found in rumens of animals fed alfalfa hay. Replacement of the bicarbonate-phosphate buffer used to maintain fermentor pH at 6.7 with phosphate alone did not greatly alter the fermentation products produced from a hay-concentrate substrate.

Acetates↗
PubMed1966

Lysis of Vibrio succinogenes by ethylenediamine-tetraacetic acid or lysozyme.

Wolin, M. J. (University of Illinois, Urbana). Lysis of Vibrio succinogenes by ethylenediaminetetraacetic acid or lysozyme. J. Bacteriol. 91:1781-1786. 1966.-Cell suspensions of Vibrio succinogenes are lysed by ethylenediaminetetraacetic acid (EDTA) or lysozyme. Lysis occurs at alkaline pH and is prevented by 0.15 m NaCl or KCl or 0.3 m sucrose. The addition of 10(-3)m Mg(++), 10(-3)m spermine, or 10(-2)m Ca(++) prevents lysozyme lysis, and 10(-4)m spermine prevents EDTA lysis. EDTA lysis leads to the formation of a cell ghost, and lysozyme lysis leads to the formation of an empty round body. Freezing and thawing of cells permits lysozyme attack which is not prevented by the protective agents mentioned above. Much of the cell protein, and almost all of the nucleic acids, are released from the cells during EDTA lysis. Treatment of frozen-thawed cells with lysozyme at neutral pH does not cause release of more than 50% of the cell protein and 60% of the nucleic acids of the cells.

Bacterial Proteins↗
PubMed1965

Basis for the exclusion of Escherichia coli from the rumen ecosystem.

The possible causes for the exclusion of Escherichia coli from the rumen ecosystem were investigated. Evidence presented indicates that oxidation-reduction potential, temperature, pH, CO(2), volatile fatty acids, traces of heavy metals, and bacteriophage are not environmental factors which select against E. coli in the rumen ecosystem. The feeding of nutrients utilizable by E. coli to an artificially inoculated continuous-culture rumen ecosystem did not prevent the washout of the E. coli from the continuous cultures. The presence of an inhibitor of E. coli growth was demonstrated. High concentrations of rumen fluid (50 to 100%) were necessary to inhibit growth in Antibiotic Medium 3. The inhibitor may operate to control the growth of E. coli in the rumen ecosystem. Because of the presence of an inhibitor, the possibility that rumen fluid is deficient in nutrients to support the growth of E. coli cannot be eliminated.

Animals↗
PubMed1964

Viologen dye inhibition of methane formation by Methanobacillus omelianskii.

Wolin, E. A. (University of Illinois, Urbana), R. S. Wolfe, and M. J. Wolin. Viologen dye inhibition of methane formation by Methanobacillus omelianskii. J. Bacteriol. 87:993-998. 1964.-Low concentrations of methyl or benzyl viologen inhibit the formation of CH(4) from ethanol and CO(2) by washed cells of Methanobacillus omelianskii. Hydrogen, which is normally formed from ethanol, accumulates in greater quantities when CH(4) formation is inhibited by viologens. The viologens do not stimulate H(2) formation from ethanol in the absence of CO(2). Inhibition of CH(4) formation by the viologens is not reversed by H(2). A variety of other dyes and possible electron acceptors were tested for inhibition, and none was inhibitory in the same low-concentration range at which the viologens were effective.

Carbon Dioxide↗
PubMedDate not supplied

Disk edema in an overweight woman.

A 46-year-old extremely obese black woman presented with headaches, blurred vision, and visual obscurations. Her exam was notable for bilateral severe papilledema, retinal hemorrhages, and lethargy. Her CAT scan was normal, and a spinal tap revealed a very high opening pressure. Although this patient's presentation mimicked pseudotumor cerebri, the lethargy and retinal hemorrhages were atypical. Her hospital evaluation was notable for elevation of the serum bicarbonate level, and she was subsequently found to have hypoxia and hypercapnia on a blood gas. The patient was diagnosed as Pickwickian syndrome, with obstructive sleep apnea. Treatment of the pulmonary problem resulted in dramatic improvement in her eye findings and her lethargy, and optic nerve sheath fenestration was not necessary.

Female↗
PubMedDate not supplied

Low-dose daily subcutaneous interleukin-2 in combination with highly active antiretroviral therapy in HIV+ patients: a randomized controlled trial.

PURPOSE: Previous studies with intermittent interleukin-2 (IL-2) therapy using intermediate and high levels of IL-2 have demonstrated significant increases in the CD4 + T cell count in HIV-infected patients. Intermittent regimens are amenable to outpatient use, but severe adverse events are frequently experienced with intermediate- and high-dose levels of IL-2. Therefore in this study, the effect of daily, subcutaneous low-dose IL-2 therapy on safety and immunological endpoints was investigated to determine whether immunological benefit could be achieved without toxicity in HIV-infected patients also receiving highly active antiretroviral therapy (HAART). METHOD: A total of 115 patients were enrolled in the trial. Fifty-six asymptomatic HIV-infected patients who had CD4 + T cell counts less than 300 cells/microL at screening and a stable HIV viral load received low-dose IL-2 (1.2 million IU [MIU]/m 2 beginning dose) once daily in conjunction with HAART (IL-2 group). Fifty-nine patients received HAART alone (control group). RESULTS: A dramatic effect of IL-2 on the natural killer (NK) cell population was observed with mean increases of 156 cells/microL in the IL-2 group compared to 19.93 cells/microL in the control group (p <.001). Additionally, IL-2-treated patients experienced a statistically significant increase in the mean percentage of CD4 + T cells (3.52% increase) when compared to control patients (1.33% increase) (p <.001). The expanded CD4 + T cell population was primarily of the naive phenotype, with mean increases of 4.53% for the IL-2 group and 0.31% for the control group (p <.001 for between-group difference). In addition, a higher proportion of IL-2-treated patients (67%) compared to control patients (33%) achieved increases of greater than 50% in the CD4+ T cell count (p =.08). Adverse events of grade 3 or grade 4 toxicity were infrequent in the current study and were substantially lower by comparison to those in studies of intermittent dose IL-2 therapy. Also, negligible changes in the HIV viral load from baseline to final measurement were observed in both groups. A trend toward a reduced number of modifications of antiretroviral therapy was apparent in the IL-2 group when compared to control patients. CONCLUSION: Daily, low-dose subcutaneous IL-2 therapy in conjunction with HAART is safe and well tolerated and is effective in expanding lymphocyte cell types including NK cells and naive T cells in individuals who have <300 CD4+ T cells.

Adult↗