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K Ijichi

Publications and source records attributed to K Ijichi.

28 records · Page 2Linked to original sources

Topical treatment with BV-araU of immunosuppressed and immunocompetent shaved mice cutaneously infected with herpes simplex virus type 1.

Effect of topical treatments with BV-araU was tested in cutaneous infections of shaved Balb/c mice with herpes simplex virus type 1. Evolution of zosteriform skin lesions associated with infection with a low virulent KOS(S) strain was almost completely suppressed by treatments with 5% BV-araU cream given 4 times daily for 5 days starting 1 day after inoculation. This effect was equivalent to that of Zovirax Cream including 5% acyclovir. One percent BV-araU cream was also effective in inhibiting progression of symptoms, while 0.2% cream was not effective. Five percent BV-araU cream significantly suppressed progression of skin lesion even if initiation of treatment was delayed to 2 days after infection. However, the efficacy was diminished by further delay in starting treatment. The effect of BV-araU cream was also evident during infection of immunosuppressed mice. Virus titers in the skin tissue encompassing the inoculation site of mice decreased the day after the first treatment. In the lower flank site, virus replication was almost completely suppressed by the treatment beginning 1 day postinfection. Topical application of BV-araU may be useful therapy for HSV-1 infections in humans, including immunocompromised patients.

Administration, Topical↗

Efficacy of oral treatment with BV-araU against cutaneous infection with herpes simplex type 1 in shaved mice.

The effect of oral BV-araU was tested in cutaneous model infections of shaved Balb/c mice with herpes simplex virus type 1 (HSV-1). Progression of cutaneous symptoms associated with cutaneous infection with HSV-1 F strain was inhibited by BV-araU at doses of 20 and 50 mg/kg twice daily, beginning one day post-infection, resulting in significant increase in the survival rate. Onset of disease was suppressed in most animals receiving 100 mg of BV-araU per kg. BV-araU (20 mg/kg or more) also significantly increased the survival rate of mice infected with HSV-1 WT-51 strain. The efficacy of BV-araU was not affected by gender or age (6-9 weeks) of the mice. BV-araU was effective even when the treatment was started 2.5 days post-infection. The efficacy of BV-araU against F strain infection was comparable to that of acyclovir, but acyclovir showed therapeutic effects at lower doses compared with BV-araU against WT-51 strain infection. Against infection of cyclophosphamide-treated immunosuppressed mice with HSV-1 KOS(S) strain, BV-araU decreased the morbidity rate and severity of symptoms at doses of 200 and 100 mg/kg, respectively, and all mice given 50 mg of BV-araU or more per kg survived, suggesting oral efficacy can be achieved against HSV-1 infections in immunosuppressed individuals.

Acyclovir↗

Antiviral potencies of BV-araU and related nucleoside analogues against varicella-zoster virus in different cell lines.

1-beta-D-Arabinofuranosyl-E-5-(2-bromovinyl)uracil (BV-araU) and nine other antiherpesviral nucleoside analogues were compared for their potencies against four strains of varicella-zoster virus (VZV) on three different cell lines: HEL cells, Vero cells, and MS cells established from a human malignant schwannoma. In contrast to the activity against herpes simplex virus type 1 previously reported, BV-araU showed extremely marked antiviral activity against VZV even on Vero cells. ED50, 50% plaque reduction dose, of BV-araU for VZV was 0.20-3.1 and 0.14-0.63 ng/ml on Vero cells and on HEL cells, respectively. Potency of BV-araU on MS cells was similar to that on these cell lines. There was not significant variation in anti-VZV activities of other nucleoside analogues on these three different cell lines except a few combinations of VZV strain and test compound.

Animals↗

Effect of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil against herpes simplex virus type 1 infection in immunosuppressed mice.

1-beta-D-Arabinofuranosyl-E-5-(2-bromovinyl)uracil (BV-araU) reduced the mortality rates of (i) 7-week-old, cyclophosphamide-treated, immunosuppressed mice (CYP mice) intraperitoneally infected with a moderately virulent strain of herpes simplex virus type 1 and (ii) 4-week-old CYP mice infected with a less virulent strain at doses of 20 and 50 mg/kg of body weight twice daily and 5 mg/kg, respectively. The degree of efficacy of BV-araU was equivalent to that of acyclovir in 4-week-old CYP mice infected with the less virulent strain. BV-araU (20 mg/kg) suppressed viral growth in various organs of CYP mice.

Acyclovir↗

Pasteurization of salted whole egg inoculated with Arizona or Salmonella.

Recently, Arizona bacteria, close relatives of Salmonella, were recovered from salted whole egg that had been pasteurized by the presently recommended process of 63.3 degrees C (146 degrees F) for 3.5 min. Because of this and the fact that the heat resistance of Arizona in salted whole egg had not been determined, the present study was undertaken. Arizona or Salmonella, grown in Trypticase soy broth supplemented with 2% yeast extract in Fernbach flasks covered with aluminum foil over cotton and guaze at 35 degrees C with shaking at 176 rpm for about 96 h, were found to have the greatest degree of heat resistance. As expected, these cells, when inoculated into salted whole egg at 10(7) cells per ml, survived heating at 63.3 degrees C (146 degrees F) for 3.5 min in a two-phase slug flow heat exchanger. To consistently achieve a 7-log kill of typical Salmonella or Arizona, a treatment of 67 degrees C (152.6 degrees F) for 3.5 min was required. However, if a 7-log kill is mandatory, it remains to be determined whether this process affect the functional properties of this product.

Eggs↗

Heat resistance of Salmonella in various egg products.

The heat-resistance characteristics of Salmonella typhimurium Tm-1, a reference strain in the stationary phase of growth, were determined at several temperatures in the major types of products produced by the egg industry. The time required to kill 90% of the population (D value) at a given temperature in specific egg products was as follows: at 60 C (140 F), D = 0.27 min for whole egg; D = 0.60 min for whole egg plus 10% sucrose; D = 1.0 min for fortified whole egg; D = 0.20 min for egg white (pH 7.3), stabilized with aluminum; D = 0.40 min for egg yolk; D = 4.0 min for egg yolk plus 10% sucrose; D = 5.1 min for egg yolk plus 10% NaCl; D = 1.0 min for scrambled egg mix; at 55 C (131 F), D = 0.55 min for egg white (pH 9.2); D = 1.2 min for egg white (pH 9.2) plus 10% sucrose. The average Z value (number of degrees, either centigrade or fahrenheit, for a thermal destruction time curve to traverse one logarithmic cycle) was 4.6 C (8.3 F) with a range from 4.2 to 5.3 C. Supplementation with 10% sucrose appeared to have a severalfold greater effect on the heat stabilization of egg white proteins than on S. typhimurium Tm-1. This information should be of value in the formulation of heat treatments to insure that all egg products be free of viable salmonellae.

Egg White↗

Effect of pH and chelating agents on the heat resistance and viability of Salmonella typhimurium Tm-1 and Salmonella senftenberg 775W in egg white.

Supplementation of egg white at pH 8.9 with 5 mg of disodium ethylenediaminetetraacetic acid (EDTA) per ml resulted in a kill of Salmonella typhimurium Tm-1 of greater than 10(6) per ml after 28 days at 2 C. While at 28 C, supplementation with 7 mg of EDTA per ml resulted in approximately a 10(6) kill in less than 24 hr. Kena supplementation at 40 mg/ml of egg white resulted in a kill of S. typhimurium Tm-1 of greater than 10(6) after approximately 60 hr of storage at 28 C. This is in contrast to no reduction in viable count in unsupplemented egg white stored at 2 C and a 100-fold increase in viable count in that stored at 28 C. Supplementation of egg white with EDTA at 7 mg/ml or with Kena at 10 mg/ml also affected the heat resistant characteristics of the two organisms at 52.5 C, reducing the time required to kill 90% of the population (D value) at any pH by a factor of 2 to 6. There was a synergistic effect between EDTA and lactic acid when lactic acid was used to adjust EDTA-supplemented egg white to an acidic pH (5.3) which greatly decreased the heat resistance of Salmonella senftenberg 775W (from 100D to D).

Chelating Agents↗

Synthesis and antiviral activities of 5-substituted 1-(2-deoxy-2-C-methylene-4-thio-beta-D-ertythro-pentofuranosyl)uracils.

Various 5-substituted 1-(2-deoxy-2-C-methylene-4-thio-beta-D-erythro-pentofuranosyl)uracils (4'-thioDMDUs) were synthesized from D-glucose via sila-Pummerer-type glycosylation. All of the beta-anomers of 5-substituted 4'-thioDMDU, except the 5-hydroxyethyl derivative, showed potent anti-HSV-1 activity (ED50 = 0.016-0.096 microgram/mL). 5-Ethyl- and 5-iodo-4'-thioDMDUs were also active against HSV-2 (ED50 = 0.17 and 0.86 microgram/mL, respectively). 5-Bromovinyl-4'-thioDMDU was particularly active against VZV (ED50 = 0.013 microgram/mL).

Antineoplastic Agents↗