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G Suzuki

Publications and source records attributed to G Suzuki.

159 records · Page 9Linked to original sources
PubMed1966

Effect of spermine on lysis and reproduction by bacteriophages phi-X174, lambda, and f2.

Groman, Neal B. (University of Washington, Seattle), and Grace Suzuki. Effect of spermine on lysis and reproduction by bacteriophages phiX174, lambda, and f(2). J. Bacteriol. 92:1735-1740. 1966.-A test was made of the hypothesis that lysis by all bacteriophages shares as a common and critical step an alteration in the osmotic stability of the infected cell. This was done by examining the effect of spermine on lysis. Spermine is one of a number of compounds which can stabilize spheroplasts and protoplasts to lysis in distilled water. Spermine stabilized both phiX174- and f(2)-infected cells at concentrations ranging from 2 x 10(-3) to 4 x 10(-2)m, but failed to stabilize lambda-infected cells at concentrations up to 8 x 10(-2)m. Stabilization was reflected both in optical density measurements and in the retention of mature phage in structures sedimentable at low speeds. At optimal concentration, over 90% of the phage was retained in these structures. These data suggest that the mechanism of lysis by phiX174 and f(2) differs sharply from that caused by lambda, and other observations suggest that there are differences in the lytic process of phiX174 and f(2) as well. Spermine also displayed a differential effect on phage reproduction. The reproduction of lambda and f(2) was inhibited by spermine, though the data do indicate that maturation occurs in its presence. The reproduction of phiX174 was enhanced by spermine.

Bacteriolysis↗
PubMed1965

Effect of ribonucleic acid phage superinfection on lysis-inhibited Escherichia coli.

Groman, Neal B. (University of Washington, Seattle), and Grace Suzuki. Effect of ribonucleic acid phage superinfection on lysis-inhibited Escherichia coli. J. Bacteriol. 90:1007-1012. 1965.-Induced culturesof Escherichia coli K-12(lambda112)F(+) were superinfected with ribonucleic acid phage f2 at various times to test for the specificity of lysis inhibition and the concurrent inhibition of growth. When f2 superinfection occurred within 90 min after induction, lysis was observed in normally lysis-inhibited cultures. Later superinfections produced very little lysis. Following early superinfection, both lambda112 and f2 phages were produced in induced cells. When superinfection occurred during the period in which growth was inhibited, f2 production was totally inhibited. The inhibition of f2 was not due to its inability to adsorb, nor was it due to damage inflicted on cells by ultraviolet irradiation or to exhaustion of the medium. The data suggest that inhibition of lysis of induced K-12(lambda112)F(+) is phage-specific, whereas the accompanying inhibition of growth is nonspecific.

Coliphages↗
PubMedDate not supplied

Acute ventricular reduction with the acorn cardiac support device: effect on progressive left ventricular dysfunction and dilation in dogs with chronic heart failure.

BACKGROUND AND AIM: Surgical resection of myocardium that acutely reduces left ventricular (LV) volume in patients with advanced heart failure (HF), the so-called "Batista Operation," remains controversial. We examined the effects of acute LV reduction with the Acorn Cardiac Support Device (CSD) in dogs with HF (LV ejection fraction < 30%). METHODS: HF was produced in 15 dogs by intracoronary microembolization. In nine dogs, intravenous dobutamine was administered to reduce LV end-diastolic dimension (LVEDD) by 10%-25%. While on dobutamine infusion, the CSD, a preformed knitted polyester device, was surgically placed around the ventricles, anchored to the arteriovenous (AV) groove, and tailored anteriorly to fit snugly over the ventricles. Dogs were then weaned off dobutamine. RESULTS: On average, the procedure reduced LVEDD by 7 +/- 1 mm (range 5-12 mm). Of the nine dogs, two died before completion of the study and seven survived for the entire period. Six dogs did not undergo device placement and served as controls. All were followed for 3 months prior to sacrifice. In controls, LV end-diastolic volume increased after 3 months (66 +/- 5 mL vs 77 +/- 6 mL; p = 0.007), while in CSD-treated dogs (n = 7), it decreased (80 +/- 5 mL vs 60 +/- 3 mL; p = 0.002). In controls, LV ejection fraction (EF) decreased after 3 months (27 +/- 1% vs 23 +/- 1%; p = 0.001) but was unchanged in CSD-treated dogs (25 +/- 1% vs 26 +/- 1%; p = 0.66). Compared to controls, CSD-treated dogs showed improved LV diastolic dysfunction and chamber sphericity, decreased wall stress, and no functional mitral regurgitation (MR). CONCLUSION: In dogs with advanced HF, acute LV reduction with the Acorn CSD prevents progressive global LV dilatation and ameliorates functional MR.

Acute Disease↗