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M Kita

Publications and source records attributed to M Kita.

At least 145 records · Page 8Linked to original sources

[Detection of the deletion of interferon-alpha and beta genes in lymphoblastoid cells by PCR].

The HuIFN-alpha and beta genes were examined by the PCR method in the 11 human lymphoblastoid cell lines. The results showed that the homozygous deletion of HuIFN-alpha and beta genes was detected in 5 of 11 cell lines and in 5 of 11 cell lines, respectively. The deletions of both the HuIFN-alpha and beta genes were observed in 4 of 11 cell lines. One T cell leukemia cell line deleted only HuIFN-alpha gene, while the other T cell leukemia line deleted only HuIFN-beta gene. This suggests that the deletions of HuIFN-alpha and beta genes may be related the development of leukemia or lymphoma.

Burkitt Lymphoma↗

Retinal adhesive force in living rabbit, cat, and monkey eyes. Normative data and enhancement by mannitol and acetazolamide.

Small retinal detachments (blebs) were made in living eyes by injecting balanced salt solution into the subretinal space with a micropipette. A second micropipette, inserted into the same bleb, measured subretinal pressure using a resistance servonulling system. The adhesive force was calculated from the pressure difference across the retina according to Laplace's law. The retinal adhesive force in rabbit, cat, and monkey eyes averaged 1.0, 1.8, and 1.4 x 10(2) dyne/cm, respectively. In rabbit eyes, 2 hr after intravenous administration of 15 mg/kg acetazolamide, the retinal adhesive force was increased to 133%. In monkeys, this dose of acetazolamide increased retinal adhesion to 144% of control values. Mannitol (2 g/kg) increased retinal adhesion in the monkey to 153% of control values 90 min after intravenous injection (compared with an increase of 145% in previous experiments in the rabbit). Because both mannitol and acetazolamide enhance retinal adhesiveness in living primate eyes, it seems likely that they will have a similar effect in humans that they may be clinically useful.

Acetazolamide↗

Effects on retinal adhesive force in vivo of metabolically active agents in the subretinal space.

The in vivo effects on the retinal adhesive force of injecting metabolically active agents into the subretinal space of rabbits were studied. Small retinal detachments (blebs) were made in living Dutch rabbit eyes by injecting experimental solutions into the subretinal space with a micropipette. A second micropipette, inserted into the same bleb, measured fluid pressure using a resistance servonulling system. The adhesive force was calculated according to Laplace's law. Blebs containing dibutyryl cyclic adenosine monophosphate, furosemide, and amiloride showed retinal adhesiveness to be decreased to 69%, 86%, and 81% of control values, respectively. Dibutyryl cyclic guanosine monophosphate and acetazolamide had no significant effect. Ouabain increased retinal adhesiveness to 119% of normal. The nonspecific metabolic toxin, dinitrophenol, reduced adhesiveness to an unmeasurable level. For some agents, the rate at which subretinal fluid was absorbed also was measured. Furosemide and amiloride in the subretinal space caused slight slowing of subretinal fluid absorption; acetazolamide had no effect. These data support the concept that metabolic factors contribute to retinal adhesion in vivo.

Adhesiveness↗

Lowering the calcium concentration in the subretinal space in vivo loosens retinal adhesion.

Retinal adhesiveness in vitro is reduced by lowering the external calcium (Ca2+) concentration. The effects of lowering subretinal Ca2+ concentration in living rabbit eyes was investigated by making experimental retinal detachments (blebs) filled with Ca(2+)-free disodium edetate solution. Unlike blebs made with Hanks' solution, these low-Ca2+ blebs enlarged progressively after they were formed, and they were surrounded by a wide whitish halo. This halo region had weak adhesion (shown by the rapid spread of fluorescein solution into the halo and by the measurement of local adhesiveness after enucleation). The retinal pigment epithelial microvilli in the halo appeared stretched toward the center of the blebs as if there had been retinal traction or movement. Measurements of retinal adhesiveness in vivo showed it to be decreased to about 30% of normal by use of this solution.

Adhesiveness↗

Systemic mannitol increases the retinal adhesive force in vivo.

The effect of systemic mannitol administration on retinal adhesive force in the rabbit was investigated in vivo. The retinal adhesive force, 1 hour after intravenous mannitol injection (2.5 g/kg), was 45% greater than that in control eyes. When adhesiveness had been weakened by injecting Ca(2+)-free edetic acid (EDTA) solution into the subretinal space, intravenous mannitol still enhanced adhesion. Mannitol administration seems to be effective in enhancing retinal adhesion, even under the conditions where it has been weakened by other mechanisms.

Adhesiveness↗

Production of human alpha- and gamma-interferon is dependent on age and sex and is decreased in rheumatoid arthritis: a simple method for a large-scale assay.

We examined host ability to produce alpha- and gamma-interferon on a large scale by culturing 2 ml of peripheral blood for 20 hr with Sendai virus or concanavalin A as inducer of alpha- or gamma-interferon, respectively. Production of gamma- but not alpha-interferon was lower in females (n = 351) than in males (n = 531) (P less than 0.001). Both alpha- and gamma-interferon production declined gradually with ageing. The production of alpha-interferon (3,233 +/- 1,773 IU/ml) and gamma-interferon (19 +/- 20 IU/ml) in rheumatoid arthritis patients was significantly lower than the values found in total and age-matched healthy donors (P less than 0.01). These results suggest that interferon production is dependent on age and sex and is significantly lower in patients with rheumatoid arthritis.

Adolescent↗

Impaired interferon-alpha production in whole-blood cultures from bladder cancer patients.

Interferon-alpha (IFN-alpha) production was investigated in whole-blood cultures of 66 bladder cancer patients and 65 control subjects. IFN synthesis was induced with Sendai virus, and IFN activity was assayed in FL cells challenged with vesicular stomatitis virus (VSV). The mean levels of the IFN-alpha produced were 5,724 +/- 2,288 IU/ml in the control subjects and 4,800 +/- 2,353 IU/ml in the bladder cancer patients. IFN-alpha production was significantly suppressed in the bladder cancer patients compared with that in the control subjects (P less than 0.05). The impairment in IFN-alpha production correlated with the tumor grade, and it was shown that the tendency toward decreased IFN-alpha production was closely associated with the advancement of the tumor stage. Our results suggested that the decreased IFN-alpha production may contribute to the disordered immunoregulation in bladder cancer patients.

Aged↗

Photothermal, cryogenic, and diathermic effects of retinal adhesive force in vivo.

Argon laser photocoagulation, cryoretinopexy, and diathermy of moderate intensity is applied to 140 rabbit eyes. Retinal adhesive force is measured from 1 day to 6 months following the treatment, using the authors' new in vivo method. A small retinal detachment is induced within the area surrounded by the burns. At the moment when the detachment starts to expand beyond the burns, subretinal pressure is measured using a resistance servo-nulling method. Retinal adhesive force is then calculated according to Laplace's law and compared with that of untreated eyes. Both photocoagulation and diathermy enhanced adhesiveness within 24 hours to 128% and 122%, respectively, of normal levels. Cryoretinopexy reduced the retinal adhesiveness during the first week, but afterwards generated as much adhesiveness as the other two methods. Beyond 6 months, under the conditions described here by the authors, the adhesive force was stronger after diathermy (279%) than after cryoretinopexy (214%) or laser photocoagulation (220%).

Animals↗

[Establishment of double grafted tumor model in mice and role of "tumor necrosis factor" (TNF)].

A double grafted tumor model (colon 26 and Meth-A) was established in BALB/c mice. The primary colon 26 tumor growth was inhibited by the secondary transplantation of Meth-A tumor cells into the same host, and the prolongation of mean survival time was also observed. To investigate the mechanism of the prolongation of survival, the role of tumor necrosis factor (TNF) was examined. The intraperitoneal inoculation of human TNF-alpha (1 x 10(4) units) for 5 days, as well as the secondary Meth-A tumor cell transplantation, resulted in the prolongation of survival. Moreover, the prolongation of survival disappeared by the inoculation of rabbit anti-TNF-alpha antibodies. These results suggest that TNF-alpha play an important role in the mechanism of a prolongation of survival by the secondary transplantation of the tumor cells.

Animals↗

Lamellar scleral resection enhances subretinal fluid absorption in eyes with choroidal congestion.

The effects of choroidal congestion and lamellar scleral resection on the absorption of subretinal fluid were studied in rabbit eyes. Small retinal detachments were induced and choroidal congestion was produced by ligating two vortex veins. Absorption time was prolonged in these eyes to roughly 138% of that in the control eyes. The choroidal congestion could be alleviated by partial thickness scleral resection, after which the absorption time was only 115% of that in untreated eyes. Our data suggest that lamellar scleral resection relieves elevated choroidal tissue pressure and helps to absorb the subretinal fluid.

Absorption↗

Evaluation of polyvinyl alcohol hydrogel as a soft contact lens material.

We prepared a transparent polyvinyl alcohol (PVA) hydrogel from a PVA solution in a mixed solvent consisting of water and a water-miscible organic solvent by cooling. The physical properties of the hydrogel were evaluated in various mixed solvents and compared with those of commercially available soft contact lens materials, such as polyhydroxyethyl methacrylate (PHEMA) and copolymers of methylmethycrylate (MMA) and N-vinyl pyrrolidone (N-VP). The PVA hydrogel showed higher tensile strength and elongation before breaking than did the other materials. Also, the PVA hydrogel was comparable in its high water content and its oxygen permeability with the MMA/VP copolymers. The protein adsorption of the PVA hydrogel was much lower than that of the other materials. Soft contact lenses of PVA hydrogel were applied to rabbit eyes for 12 weeks. The effects of the lenses on the cornea were studied by biomicroscopy, ultrasonic pachymetry, and histopathologic examination. No abnormal findings were noted, suggesting that the PVA hydrogel may be promising as a new material for use in soft contact lenses.

Animals↗

Plasma dehydroepiandrosterone-to-cortisol ratios as an indicator of stress in gynecologic patients.

To evaluate the usefulness of the plasma dehydroepiandrosterone (DHEA)-to-cortisol ratio (D/C) and the plasma aldosterone-to-plasma renin activity ratio (ALDO/PRA) as indicators of stress, we first monitored changes in these ratios associated with surgery in 13 patients who were healthy except for their localized gynecologic diseases. D/C and ALDO/PRA ratios were reduced by 37 and 42%, respectively, 4-5 days postsurgery compared to those 3-4 days before surgery (P less than 0.05 and P less than 0.01, respectively) and returned to preoperative levels 11-13 days after surgery. In contrast, individual hormone levels showed no significant changes associated with surgery. Having documented that these ratios may serve as indicators of stress, we then sequentially measured D/C ratios in patients with gynecologic malignancy subjected to cytotoxic chemotherapy or radiation therapy and in patients in the terminal stage. Although such therapies did not affect D/C ratios to a measurable extent, patients in the terminal stage gave consistently low D/C ratios in spite of normal vital signs (a D/C ratio below 6 was deemed low). Such low ratios occurred only sporadically in other patients and, again, individual values for DHEA and cortisol showed no consistent pattern. We believe that use of D/C ratios as an indicator of stress warrants further investigation.

Aldosterone↗

[Effects of age and gender on serum levels of apolipoprotein A-I, A-II, B, C-II, C-III and E, measured by turbidimetric immunoassay, in normolipidemic Japanese elderly].

Accumulating evidence has suggested significant roles of apolipoproteins in lipoprotein metabolism. Therefore it is important to measure serum levels of apolipoproteins to understand the pathophysiology of lipid metabolism. The newly developed turbidimetric immunoassay (TIA) method for the determination of serum apolipoprotein concentration is the first method which can be employed with autoanalyzer, and is expected to be used widely. The standard values of serum concentrations of apolipoproteins measured by the TIA method for Japanese adults and children have been reported recently, but not yet for the elderly. Therefore, we investigated serum concentrations of apolipoproteins (A-I, A-II, B, C-II, C-III and E) in healthy normolipidemic elderly, aged 65-99 years, in order to obtain the standard values of apolipoproteins for the elderly. The subjects consisted of 84 males and 91 females. They had normal serum values for total cholesterol (TC) (120-220 mg/dl) and triglyceride (TG) (50-150 mg/dl). No one demonstrated clinical, biochemical or haematological evidence of cardiovascular, peripheral-vascular, cerebrovascular, hepatic, renal or endocrine disorders. Between-assay and intra-assay coefficient variations were approximately 5% and approximately 1.5%, respectively, in all apolipoproteins examined.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

[Interferon-alpha producing capacities in prostatic cancer patients].

Interferon-alpha (IFN-alpha) producing capacity was measured in 47 patients with prostatic cancer by whole blood assay. The mean IFN-alpha producing capacity of prostatic cancer patients was 3657 IU/ml, which indicated a significantly (p less than 0.005) lower value than that in healthy male aged 50 years or more. IFN-alpha producing capacity in patients with Stage D disease was lower than that with Stage A, B or C. The higher the grade of the disease, the lower tended to be the capacity. A certain relationship was suspected between IFN-alpha producing capacity and the prognosis of each patient. In particular, in patients with prostatic cancer in Stage D, the prognosis was worse in low IFN-alpha producing capacity group (less than 3000 IU/ml) than in normal or high IFN-alpha producing capacity group (greater than or equal to 3000 IU/ml). It was considered that IFN-alpha producing capacity might be useful in developing the prognosis of patients with prostatic cancer.

Humans↗

[Radiotherapy on the basis of quality of life].

Considering the relationship between tumor lethal dose and normal tissue tolerance: the therapeutic ratio, radiation oncologists have been performed the radiotherapy for cancer patient. The basic principle of radiotherapy is to have a good result (curability), to be tolerable in side effects and to have a comfortable life after radiation. Radiotherapy is the important strategy for an early stage of cancer with conserving the function and structure, and for an advanced or a recurrent stage of cancer with contributing to improve the quality of life. Recently, advantage of radiation tools and supportive care of cancer treatment, have been able to decrease the incidence of late injuries and complications. Radiotherapy must be planned on basis of considering therapeutic ratio and should be performed with optimum radiation in the multimodal treatment for cancer.

Humans↗

[Interferon-producing capacity in patients with prostate cancer: prognosis value].

The interferon (IFN)-alpha and -gamma producing capacities were measured in 47 patients with prostatic cancer by the whole blood method. The mean IFN-alpha producing capacity in prostatic cancer patients was 3,657 IU/ml, which indicated a significantly (P less than 0.005) lower value than that in healthy male control aged 50 years or more (mean value, 4,988 IU/ml), while the IFN-gamma producing capacity was almost normal. The IFN-alpha and -gamma producing capacities in patients with stage D disease was decreased as compared with that in patients with stage A, B or C. The higher the grade of the diseases, the lower the IFN producing capacity tended to be. In patients with prostatic cancer, the prognosis was worse in low IFN producing capacity group than in normal or high IFN producing capacity group. These results suggest that the measurement of IFN producing capacity is useful for the estimation of the prognosis of patients with prostatic cancer, and that the IFN producing capacity may be a factor which decides the prognosis.

Aged↗