Antibacterial activity and clinical efficacy of sparfloxacin in Mycobacterium avium-intracellulare complex infection.

In Japan the incidence of atypical mycobacteriosis has steadily increased, with Mycobacterium avium-intracellulare complex (MAC) the most common infecting organism. A standard chemotherapy regimen for MAC infection has not been established because of significant resistance to anti-mycobacterial drugs. Sparfloxacin has good antimicrobial activity against several acid-fast bacteria and is expected to be an effective drug for treating mycobacteriosis. We examined the effects of adding sparfloxacin to anti-tuberculotic combination therapy in six patients with MAC pulmonary disease. Drug susceptibility was also assessed using the agar dilution method. The minimum inhibitory concentrations (MICs) for sparfloxacin, levofloxacin, isoniazid, rifampicin, streptomycin, ethambutol and clarithromycin was measured in clinical isolates from all patients; sparfloxacin showed the lowest MIC. Bacteriological and clinical improvements were observed in the four patients who completed the study. Dosing was discontinued in two patients because of pruritic skin eruptions. Sparfloxacin shows promise as an anti-mycobacterial agent for treating MAC pulmonary disease.

[Clinical utility and safety of diagnostic thoracoscopy].

The increasing use of thoracoscopy performed under local anesthesia has made contributions to the diagnosis of pleural disease with effusion. During the past 7 years, we have performed 100 such thoracoscopy procedures using a flexible fiberoptic bronchoscope. On the basis of our clinical findings, we are able to discuss the utility and safety of this procedure. The causes of pleural effusion were carcinomatous pleurisy in 72 cases, tuberculosis pleurisy in 15 cases, infection without tuberculosis in 4 cases, malignant pleural mesothelioma in 8 cases and one case of asbestosis. The success rate of thoracoscopic pleural biopsies were 97% for carcinomatous pleurisy, 100% for malignant pleural mesothelioma and 86% for tuberculosis pleurisy. This procedure was performed with no serious effect on blood pressure, oxygen saturation, monitored ECG or BGA data, and with no serious complications. Therefore, we concluded that this method is very useful for the diagnosis of pleural effusions and has few complications.

Suppression of the Saccharomyces cerevisiae hac1/ire15 mutation by yeast genes and human cDNAs.

We previously reported that the Saccharomyces cerevisiae ire15 mutation results in an inositol-auxotrophic phenotype, and that human cDNAs can suppress the ire15 mutation (Nikawa, J., 1994. A cDNA encoding the human transforming growth factor beta receptor suppresses the growth defect of a yeast mutant. Gene 149, 367 372; Nikawa, J., Nakano, H., Ohi, N., 1996b. Structural and functional conservation of human and yeast HAC1 genes which can suppress the growth defect of the Saccharomyces cerevisiae ire15 mutant. Gene 171, 107-111). Herein, we present evidence that the gene responsible for the ire15 mutation is HAC1, which encodes a transcription factor for KAR2, obtained by isolating a yeast single-copy supressor gene and by performing complementation analysis. Sequencing analysis revealed that the mutant HAC1 gene obtained from the ire15 mutant contained an AAA codon at position 50 instead of the AGA codon observed in the wild-type gene, resulting in the alteration of the aa from Arg to Lys. All human cDNAs and yeast multicopy suppressors, which had been isolated as suppressors for the ire15 mutation, were able to suppress the inositol-auxotrophic phenotype but not the defect in KAR2 induction of the hac1-disrupted strain.

Bleomycin-induced beta-lactamase overexpression in Escherichia coli carrying a bleomycin-resistance gene from Streptomyces verticillus and its application to screen bleomycin analogues.

A bleomycin-resistance gene, designated blmA, has been cloned from bleomycin-producing Streptomyces verticillus by Sugiyama et al. (Gene 151 (1994) 11-16). The present study shows that Escherichia coli harboring the blmA-carrying pUC plasmid overproduced beta-lactamase, encoded by an ampicillin-resistance gene on the plasmid, when cultured in the presence of bleomycin, which suggests that bleomycin may act as an inducer (or an activator) for the expression of the specific gene in the presence of blmA. We constructed a vector, designated pMAB50, which senses bleomycin and produces a pigment, using blmA and a Streptomyces tyrosinase gene located under the control of beta-lactamase promoter: E. coli harboring pMAB50 produced the melanin pigment in the presence of bleomycin-type antibiotics, suggesting that the transformed E. coli can be employed as a reporter organism to screen bleomycin analogues.

Novel assay system favorable for the study of cell-to-cell transmission of HIV-1 and its application to the evaluation of anti-HIV drugs.

The cell-to-cell transmission of human immunodeficiency virus type 1 (HIV-1) was studied using MOLT-4 cells chronically infected with a variant strain of HIV-1SF-2 (MOLT-4/HIV-1SF-2H) and CD4+ human lymphoid MT-4 cells. MOLT-4/HIV-1SF-2H cells produced less than 1 TCID50 infectious particles per day as determined by the cytopathogenicity in MT-4 cells. However, the expression of envelope glycoproteins gp120 and gp41 on the MOLT-4/HIV-1SF-2H cell membrane was satisfactory for syncytium formation with the uninfected MOLT-4 cells. When MOLT-4/HIV-1SF-2H and MT-4 cells were co-cultured, severe cytopathogenicity was observed in MT-4 cells without being accompanied by the formation of multi-nucleated cells. Thus, the system consisting of MOLT-4/HIV-1SF-2H and MT-4 cells is convenient for exclusive study of the mechanism of cell-to-cell transmission of HIV-1. Using various compounds, it was confirmed that cell-to-cell transmission required both gp120/gp41-CD4 binding and de novo DNA synthesis.

Cloning and characterization of polyphenol oxidase cDNAs of Phytolacca americana.

Two cDNA clones encoding polyphenol oxidases were isolated from a cDNA library constructed from a log-phase suspension culture of Phytolacca americana (pokeweed) producing betalains. The clones exhibit 93 and 86% sequence identity at the nucleotide and deduced amino acid levels, respectively. Both clones contain two copper-binding domains characterized by histidine-rich regions, which are found ubiquitously in all polyphenol oxidases/tyrosinases, and a putative third histidine-rich, copper-binding region, which is common to all plant polyphenol oxidases. One of the Phytolacca cDNA deduced amino acid sequences contains the ubiquitous transit peptide for all proteins targeted to the internal lumen of thylakoid membranes of plastids and is considered to be 98 residues in length based on a proposed sequence cleavage site motif. This would produce a processed peptide of approximately 54 kD. In addition to common features of transit peptides, it was found that an additional conserved region for polyphenol oxidases was located between the hydroxy amino acid-rich region and the thylakoid transfer domain. Spatial and temporal expression was investigated by northern blot analysis of total RNA from various organs of Phytolacca plants. Transcripts of the two clones were found to be 2.1 and 2.3 kb, respectively. Both transcripts were present only at substantial levels in ripening, betalain-containing fruit.

Ileocecal resection in neonates and infants: a follow-up study.

From 1977 to 1983 ileocecal resection was done in five neonates and three infants who were admitted to our pediatric surgical units. Their growth, hematology, and serum biochemistry were examined and compared with that of an ileal resection group without ileocecal resection. The body weight and height of all patients of the ileocecal resection group were within normal ranges. All patients undergoing ileocecal resection in neonates had moderate diarrhea but condition of fecal evacuation improved after age 6. None of the control ileal resection group had diarrhea since age 2. No significant differences were noted in hematology and serum biochemistry (protein metabolism, lipid metabolism, bile acid, and vitamin B12) data between the ileocecal resection groups and the control group. Our findings show that after ileocecal resection without extensive ileal resection in neonates and infants, adequate nutritional status can be maintained.

Hepatocellular carcinoma: treatment with percutaneous ethanol injection and transcatheter arterial embolization.

The therapeutic effectiveness of a new combination therapy--pretreatment with transcatheter arterial embolization (TAE) and subsequent percutaneous ethanol injection (PEI)--for solitary large (> 3.0 cm in diameter) primary hepatocellular carcinoma lesions was compared with that of TAE alone. With TAE alone, a partial response of the tumor was seen in only 10% of the patients, and the 1-, 2-, and 3-year survival rates were calculated to be 68%, 37%, and 0%, respectively. Histologic examination of specimens obtained at hepatectomy showed that TAE alone caused complete necrosis in only 20% of the tumors. In contrast, PEI combined with TAE significantly (P < .05) increased the partial response rate (45%) and significantly (P < .01) prolonged the 1-, 2-, and 3-year survival rates (100%, 85%, and 85%, respectively). Combination therapy caused complete histologic necrosis in 83% of the tumors. It also was significantly (P < .05) better than TAE alone in terms of rate of primary tumor recurrence during follow-up.

Synergistic effects of irradiation and hyperthermia on established cell lines derived from maxillary carcinoma. Report II.

We studied in vitro the capability of radiation, hyperthermia, and their combination to inhibit growth of cell strains isolated from maxillary carcinoma and their radiation tolerant strains. Synergic effects of the combination were studied by investigating effects of hyperthermia and radiation on cell cycles with BrdU pulse labelling to establish optimal conditions for the combination. Growth of cell strains from maxillary carcinoma was remarkably inhibited by thermal treatment because of retarded cellular cycles. Cells at the S-phase were so sensitive to heat that their intake of BrdU was debilitated. Radiation increased the proportion of cells at the S-phase that poorly synthesized DNA. When combining radiation with hyperthermia, the heat killed cells at the S-phase, which was prolonged by radiation, and survivors showed retarded cellular cycles; that is, synergism was found.

Synergistic effect of irradiation and hyperthermia on established cell lines derived from maxillary carcinoma. Report I.

Cultured tumor cells of an established cell line derived from cancer of the head and neck (maxillary and lingual cancer) were irradiated with X-rays (5 or 10 Gy). This treatment inhibited cell proliferation in a dose-dependent way. Cell cycle analysis showed that the ratio of cells in the S phase to the population of viable cells was higher than that in a non-irradiated control group. Thus, the S phase was prolonged by exposure to X-rays. Cell proliferation was also inhibited by 1 h of heat treatment at 43 degrees C. However, movement through the cell cycle was slowed down overall and no cell aggregation in any phase of the cell cycle was found. Proliferation of not only radioresistant but also radiosensitive cells was inhibited by this treatment. Hyperthermia at 43 degrees C for 1 h did not affect cell proliferation, nor did it influence the pattern of cell cycle distribution. However, it caused a decrease in intracellular polyamine amount. The combination of irradiation and hyperthermia caused a stronger inhibition than either treatment alone. The synergistic effect of the two treatments probably arose from the S-phase cells being heat-labile although radioresistant.

[Constituents of Berchemia racemosa Sieb. et Zucc].

Mearnsitrin-3-O-alpha-L-rhamnoside, myricitrin, narcissin and other flavones were isolated together with phenolic carboxylic acids from the leaves of Berchemia racemosa Sieb, et Zucc. From the wood of this plant, flavanones, flavanonols, phenolic carboxylic acids, (-)-catechin and other were isolated, and identified.

Effects of vitamin E, vitamin B2 and selenite on DNA single strand breaks induced by sodium chromate (VI).

The effects of vitamin E, vitamin B2 and selenite on DNA single strand breaks induced by Na2CrO4 were examined by alkaline elution. Incubation of Chinese hamster V-79 cells with alpha-tocopherol succinate (vitamin E) for 24 h prior to exposure to Na2CrO4 resulted in a decrease of DNA breaks produced by this compound. However, similar pretreatment with riboflavin (vitamin B2) or Na2SeO3 resulted in an enhanced formation of breaks induced by Na2CrO4. Pretreatment with Na2SeO3 resulted in increased levels of glutathione in these cells while levels of glutathione remained the same with vitamin E or vitamin B2. These results suggest that Na2CrO4 induced DNA breaks appear to be mediated by the formation of free radicals and/or cellular reductive metabolism.

Effect of arginine on gramicidin S biosynthesis by Bacillus brevis.

Effects of arginine on gramicidin S (GS) biosynthesis were investigated by growing Bacillus brevis ATCC 9999 in a synthetic medium consisting of 10 g fructose, 0.15 g l-proline, 1.3 g l-histidine, 1.3 g l-glutamine, 0.5 g L-methionine, 1 g L-phenylalanine and six mineral salts per liter. Supplement of 3 g/liter L-arginine to the medium, especially at the logarithmic phase of growth, enhanced the cell growth and GS production. Twice supplement of 3 g/liter arginine at the beginning and middle logarithmic phase of growth gave much more GS production than any once supplement, but the soluble GS synthetase extractable by lysozyme digestion was remarkably decreased. However, the decrease of enzyme by arginine seemed to be merely an apparent phenomenon, because GS-synthesizing ability of the cell was strongly enhanced by arginine and the enzyme which was not extracted by lysozyme digestion could efficiently be solubilized by ultrasonic homogenization. In the soluble fraction of cells grown in an arginine-added synthetic medium, no arginine was detected, but a large amount of ornithine was accumulated. When L-ornithine, instead of L-arginine, was added to the synthetic medium, cell growth and GS production was stimulated with increase of its concentration without decrease in the soluble enzyme activity.