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Biomedical subjects

H Honma

Publications and source records attributed to H Honma.

At least 19 recordsLinked to original sources
PubMed1992

Effect of serum components on syncytium formation and virus production by cells infected with human immunodeficiency virus in vitro.

Previously it has been reported that cocultivation of human immunodeficiency virus type 1 (HIV-1)-infected cells with uninfected cells results in formation of multinuclear giant cells, generated via an interaction of gp120 on the surface of infected cells with CD4 on the uninfected cells. Formation of multinuclear giant cells as occurring in the presence of normal fetal calf serum was not observed when HIV-infected MOLT-4 or MOLT-3 cells (chronically infected with HTLV-IIIB) and uninfected cells were cocultured in both serum-free medium and fibrinogen-depleted serum. Addition of sera (human and rabbit) as well as of fibrinogen (human and bovine), fibronectin (human), and alpha-globulin (human), but not of albumin, transferrin or gamma-globulin to serum-free medium caused formation of multinuclear giant cells. In contrast, HIV production from MOLT-3 cells proceeds also in the absence of serum. In control experiments it was established that the cells maintained at reduced serum concentration, or in serum-free medium without or with fibrinogen are viable even though displaying a lower metabolic rate (ATP formation and DNA synthesis). From these findings we conclude that serum components (e.g., fibrinogen, fibronectin, and alpha-globulin) are absolutely required for syncytium formation but are not essential for virus release.

Adenosine Triphosphate↗
PubMed1992

Efficacy of manidipine on circadian blood pressure in essential hypertension.

The 24-h blood pressure (BP) response to once-daily manidipine monotherapy was examined in an open, nonrandomized study of 17 patients with untreated essential hypertension. Manidipine (10-30 mg) was administered once daily for a minimum of 2 weeks. BP and heart rate (HR) were monitored every 30 min for 48 h by an ambulatory BP monitoring device (ABPM-630, Nippon Colin) before and after therapy. Manidipine significantly (p < 0.005) decreased mean systolic and diastolic BP during the entire 24 h, day-active and night-resting periods. The reduction in both systolic and diastolic BP was consistent throughout the whole day. Manidipine also significantly reduced the fractionated pressure-time indices of both systolic and diastolic BP consistently throughout the 24-h period. The circadian amplitude of BP in hypertensive patients, which was higher than that in normal reference subjects, was reduced by manidipine into the reference range. The acrophase of BP in hypertensive patients, which was similar to the reference value, was not altered by manidipine treatment. Manidipine did not change the mean HR during 24-h, day-active or night-resting periods. Therefore, once-daily manidipine monotherapy showed a consistent antihypertensive effect over 24 h and optimized the circadian amplitude of BP without an increase in HR.

Adult↗
PubMed1992

[Application of video endoscope system (EVIS200) in endourology].

We began clinical studies in April, 1989 for the purpose of utilizing the video endoscope system in the field of urology, termed the Urological Video Information System (UVIS). The UVIS is made up of an image assembling and recording system and an image filling system. Since we started using the first generation video endoscope system (EVIS-1, Olympus Optical Co.) as an image assembling system, we have encountered several major obstacles such as 1) the absolute insufficiency for the amount of light, and 2) the unclearness of frozen images. As we have been able to use as second generation video endoscope system (EVIS200, Olympus Optical Co.) since September 1990, the major components of the UVIS have been modified. In this report, we describe our clinical experience with the re-designed UVIS; EVIS200, which we have used, is composed of a video-processor (CL-200, Olympus Co.), a video converter and rigid urological scopes. The EVIS200 has been evaluated not only for the endoscopic examination but also for transurethral surgery. No problems were noticed in manipulating the EVIS200. Marked improvements were achieved in image quality. Images both on the television monitor and hard copies from the color video printer had optical quality in good agreement with the gross findings. The UVIS was a great contribution to both the authors and the patients; the findings both of the examination and the surgery could be explained to the patient and family during and/or immediately after the procedure. We believe that the UVIS may replace conventional urologic endoscopy and become an excellent date-base for endourology.

Endoscopes↗
PubMed1991

Detection of porcine rotavirus in stools by a latex agglutination test.

We developed a simple agglutination test for the detection of porcine rotavirus in stools from pigs with diarrhea. The virus was detected with high sensitivity and specificity by a slide agglutination test using latex particles coated with antibody against the porcine rotavirus strain OSU (LA-antiOSU). The agglutination of LA-antiOSU with OSU on a glass slide was evident macroscopically within 2 min. The sensitivity of this latex agglutination (LA) test was four times higher than that of the electron microscope method. The LA test is available for the rapid diagnosis of porcine rotavirus infections.

Animals↗
PubMed1991

Human immunodeficiency virus infection in cells of myeloid-monocytic lineage.

We established persistent infection with a strain of human immunodeficiency virus type 1, HTLV-IIIB, in a promyelomonocytic cell line, ML-1 (CD4 antigen nearly negative and CD4 mRNA negative), and a promonocytic cell line, THP-1 (CD4 antigen positive). Different reaction of giant cell formation was found after co-cultivation of infected and uninfected cells of ML-1, HL-60, THP-1 and U-937 cell lines with uninfected and infected MOLT4 (a T-lymphoma cell line).

CD4 Antigens↗
PubMed1991

Sensitive detection of viral antigens with a new method, "laser magnet immunoassay".

A new method, "laser magnet immunoassay" (LMIA), has been developed for sensitive detection of viral antigens. Target viruses captured on microbeads were made to react with antibodies labeled with magnetite particles. In a magnetic field, magnetically labeled antigens dispersed in water were attracted to and concentrated at one point on the surface, resulting in the lifting up of a small surface area. A laser beam which was incident on the point reflected, making an interference fringe. The intensity of the fringe indicates the amount of the magnetite conjugated with antigen. A very low concentration of antigens, such as 5 particles of influenza virus and 0.1 pg/ml of human immunodeficiency virus (HIV) p24 antigen in human serum, could be detected by this method. Application of this method to diagnoses of viral diseases in early stages is discussed.

Antigens, Viral↗
PubMed1990

Virus-like particle formation of Drosophila copia through autocatalytic processing.

Northern blot and nucleotide sequence analyses of copia RNA from a transfectant made by introducing a genomic copia into copia-free cells showed that the 2 kb RNA, one of the major transcripts of copia, is generated through splicing. Using the polymerase chain reaction (PCR), we have also found that the position of the splice sites used in Drosophila larvae and cultured cells originally containing copia is the same as that used in the transfectant. To investigate the function of the 2 kb RNA, we constructed mutant copias which harboured a single point mutation at the splice site or approximately 3 kb deletion of the internal region corresponding to the spliced out sequence. Analyses of transfectants made by introducing these mutant copias into copia-free cells demonstrated that the spliced 2 kb RNA contains sufficient information to make copia virus-like particles (VLPs). Furthermore, when copia RNA corresponding to the spliced RNA was translated in vitro, the major VLP protein was found to be released autocatalytically from its own precursor. A single amino acid substitution at the putative protease active site in the precursor prevented the processing, and resulted in accumulation of the mutant precursor in vitro. From these results, we conclude that copia VLPs are produced through autocatalytic processing of the precursor polyprotein encoded by the spliced copia RNA.

Amino Acid Sequence↗
PubMed1978

Toxicity of heavy metals and insecticides on slime mold Physarum polycephalum.

Toxicity of heavy metals and insecticides on the slime mold Physarum polycephalum was investigated in order to examine and estimate with ease the toxicity of environmental and occupational contaminants and also to study the effects of various agents on the cell membrane. Changes in survival time and in membrane potential of the slime mold were measured using a double chamber method. The results obtained suggest that their toxicity for the slime mold is accompanied by some change in the cell membrane, and that studies on toxicity for various chemical substances in the slime mold can be used as a screening method.

Animals↗
PubMed1978

[Aging properties of indium added gold alloys for metal-ceramic system (author's transl)].

Aging properties is studied on Au-10 wt% Pt and Au-10 wt% Pt-0.5 wt% Fe alloys containing 0.2, 0.4 and 2.0 wt% Indium. The results obtained are as follows: 1) In added Au-Pt alloys. From the electrical resistances in the isochronal aging curves, 0.2 and 0.4 wt% Indium added alloys are age-hardenable between 350 degrees and 640 degrees C. Heterogeneous phase in founded in 2.0 wt% Indium added alloy by meanes optical microstructures. This phase is identified fcc Pt3In by meanes X-ray diffraction. 2) In added Au-Pt-Fe alloys 0.2, 0.4 and 2.0 wt% Indium added alloys are age-hardenable between 250 degrees and 620 degrees C. Grain boundary reaction accelerated in 2.0 wt% Indium added alloy, and hardness decreased by overaging. Precipitation of nodule is inhibited in 0.2 wt% Indium added alloy, and aging properties also increase.

Ceramics↗