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Biomedical subjects

H Yago

Publications and source records attributed to H Yago.

29 records · Page 2Linked to original sources
PubMed1992

Stress and murine NK cell function: the role of blood loss.

It has been previously reported that NK cell function decreases following surgery in mice. To explore the basis of this observation, we compared the relative influence of anesthesia, surgical amputation and bleeding on NK cell cytotoxicity in C57BL/6 mice. After hind limb amputation, including with blood loss, there was a statistically significant decrease in NK cell cytotoxicity and the appearance of splenomegaly on the 4th day postoperative day. The increase in spleen size appeared to be due to either the surgical stress-induced expansion of splenic erythroblasts or erythroblast generation following blood loss. In contrast, if blood loss was minimal there was no suppression of NK cell cytotoxicity following hind limb amputation. Moreover, there was a statistically significant correlation of NK cell activity and the quantitation of total blood loss. Interestingly, the decrement in NK cell activity was not observed if blood transfusion was made, even in the presence of surgical amputation. These observations are important for defining the immune suppression reported following surgery and suggest that in human, chronic blood loss may also be associated with immune suppression.

Anesthesia↗
PubMed1992

Characterization of monoclonal IgG antibodies produced by hybridomas derived from rheumatoid synovial cells.

IgM rheumatoid factors (RF) are the predominant autoantibody found in rheumatoid arthritis. They are polyclonal, fix complement, and are directed against epitopes in the Fc portion of IgG. One hypothesis regarding the induction and persistence of RF production in rheumatoid arthritis is that the Fc of IgG is somehow altered, rendering it antigenic. In this study, to better understand the derivation and pathogenicity of RF in rheumatoid arthritis, monoclonal IgG (mIgG) constitutively secreting hybridomas were established by fusing rheumatoid synovial mononuclear cells (RSC) from patients with a mouse/human heteromyeloma cell line, F3B6. To clarify the primary structure of IgG Fc constant regions produced locally by RSC, we amplified the cDNA corresponding to the CH2 and CH3 domains of an IgG1-, IgG2-, and an IgG3-producing hybridoma derived from RSC. The amplified DNA segments were cloned in M13 vectors and sequenced. Interestingly, very few differences in the nucleotide sequences were observed, and the deduced amino acid sequences were identical, except for the allotype, with those encoded by the human germline genes GEA and CL. Thus, the primary structure of the IgG1, IgG2, and IgG3 Fc regions produced by RSC were not altered when compared with those encoded by the unmutated human germline gene. These results suggest that factors other than altered IgG induce and sustain high avidity RF production in rheumatoid arthritis.

Amino Acid Sequence↗
PubMed1991

The sources of chemical substances in allergic nasal fluid.

The sources of different chemical substances in the NF of allergic patient, such as albumin, secretory IgA, histamine, leukotriene, kinin and substance P were investigated. To accomplish this, we challenged the inferior turbinate on one side, but separately collected NF from both sides in patients with nasal allergy to house-dust. Provocation was done with paper disc containing dried allergen extract. Collection was done by suction for the first five minutes immediately after the onset of a positive response to nasal provocation. The total amount of the chemical substances on each side was analyzed separately and compared. Significant differences were seen between both sides only for histamine and leukotriene. In consideration with the previous reports, it is suggested that in nasal allergen challenge the major sources are glandular secretion for secretory IgA, and albumin, and secretion for migrating cells for histamine and leukotriene. The major sources responsible for kinin and substance P, however, are not defined.

Adolescent↗
PubMed1990

Study on pruritus in hemodialysis patients and the antipruritic effect of neurotropin: plasma levels of substance P, somatostatin, IgE, PTH and histamine.

It has been reported that Neurotropin can markedly improve pruritus in patients undergoing hemodialysis (HD). In order to elucidate the probable causes of pruritus and the antipruritic effect of Neurotropin, various biochemical parameters in the plasma of patients before and during HD were investigated. Forty-three patients undergoing HD were divided into three groups. Eighteen patients had suffered no episode of pruritus (group A), 17 patients had on-going pruritus (group B) and the remaining 8 patients had experienced improvement of pruritus following Neurotropin treatment (group C). The mean concentration of substance P was in only B group significantly increased with HD only in B group, indicating that substance P could be one of the causes of pruritus in patients undergoing HD. Neurotropin appears to exert its antipruritic effect by lowering the level of substance P. The change in parathyroid hormone (PTH) level during HD was not significant in any of the groups, but the mean concentration of PTH in group B was higher than that of group A, indicating that PTH may also be one of the causes of pruritus.

Adjuvants, Immunologic↗
PubMed1989

Study on the in vitro assay method for evaluating the inhibitory effect of various substances on the production of plasma kallikrein.

The assay method based on the principle of kallikrein-kinin cascade was established for evaluating the inhibitory effects of various substances on the production of plasma kallikrein. In this in vitro assay, it was found that indomethacin, ketoprofen, ibuprofen and an extract obtained from inflamed rabbit skin inoculated with vaccinia virus (NSP) had the inhibitory effect on the production of plasma kallikrein. Kinins generated in the reaction mixture were measured by RIA. It was shown that the generation of kinins was also inhibited by these substances. From these results, it is hoped that this assay method may be useful for screening the substances which inhibited the production of kinin.

Aminopyrine↗
PubMed1989

Study on pruritus in hemodialysis patients and the antipruritic effect of neurotropin: plasma levels of C3a, C5a, bradykinin and lipid peroxides.

The causes of pruritus in patients undergoing hemodialysis and the mechanism of the antipruritic effect of Neurotropin, an extract isolated from the inflamed dermis of rabbits inoculated with vaccinia virus and clinically used in Japan as an analgesic and antiallergic drug, were investigated by measuring the levels of C3a, C5a, bradykinin and lipid peroxides in venous blood collected before dialysis, and at 15 min and 4 hr after starting hemodialysis. C3a increased considerably in pruritic patients compared to non-pruritic patients at 15 min after starting hemodialysis. Neurotropin significantly suppressed the C3a level and improved the condition of pruritic patients. There was no significant difference in the level of bradykinin between pruritic patients and non-pruritic patients. Therefore, bradykinin was not thought to be related to the incidence of pruritus in such patients. A tendency towards lowering of the levels of lipid peroxides in the patients' plasma by Neurotropin was also observed. It seems possible that elevation of C3a may be one of the underlying causes for the appearance of pruritus, and that Neurotropin may exert its antipruritic effect through suppression of the activation of C3 in patients undergoing hemodialysis.

Bradykinin↗
PubMed1988

Release of inflammatory mediators by noxious stimuli; effect of neurotropin on the release.

Anesthetized rats were perfused with saline in the subcutaneous space of the hind paw and the release of inflammatory mediators induced by noxious stimuli was studied. Not only immunoreactive bradykinin (BK) but also histamine, serotonin (5-HT) and immunoreactive prostaglandin E2 (PGE2) were found to be released into the perfusate when the paw was pinched. Neurotropin, used clinically as an analgesic and anti-allergic drug in Japan, inhibited the release of BK in dose-dependent manner without altering the release of histamine, 5-HT and PGE2. The maximal inhibition of BK release was observed 60 min after p.o. administration of neurotropin. Indomethacin failed to inhibit the release of BK.

Animals↗
PubMed1988

[Multivariate statistical analysis of the postoperative recurrence factors in uterine cervical carcinoma].

In 211 patients with postoperative cervical carcinoma, we studied the relationship between the recurrence and various factors, and the interrelation among the factors. 1) Lymph node metastasis, clinical stage, number of complaints, adenocarcinoma and adenosquamous carcinoma, and number of pregnancies were associated with recurrence. Signs of myelic injury and large cell non-keratinizing carcinoma were associated with less recurrence. Maintenance chemotherapy markedly improved the prognosis. 2) Lymph node metastasis was frequently associated with an advanced stage, adenocarcinoma or increased erythrocyte sedimentation. Increased sedimentation was rarely associated with greater numbers of pregnancy or keratinizing carcinoma. Signs of myelic injury were rare in cases of advanced stage or large cell carcinoma and frequent in cases of long periods of illness. 3) Intrapelvic recurrence was related to early recurrence and maintenance chemotherapy, and extrapelvic recurrence to increased sedimentation, late recurrence, adenocarcinoma and no chemotherapy. 4) Early recurrence was associated with shorter periods of illness, lymph node metastasis and no chemotherapy, but late recurrence was associated with longer periods of illness, no lymph node metastasis, maintenance chemotherapy and adenocarcinoma. 5) The prognosis and the required periods of maintenance chemotherapy could be determined by Z = 4.3817.X1 + 1.2366.X2-0.0916.X3 + 2.3257.X4-1.9606.X5 + 1.6477.X6-0.1967.X7- 7.3047, with rates of inaccuracy of 13.9% for cases of no recurrence and 15.1% for recurrent cases.

Analysis of Variance↗
PubMed1986

[Colposcopy in dysplasia, carcinoma in situ and microinvasive cancer of the cervix--systematic diagnosis].

Recently colposcopy has come to be increasing used in the diagnosis of the early cervical cancer. We studied colposcopic findings (epithelial, vascular and glandular findings) of dysplasia, carcinoma in situ and microinvasive cancer of the uterine cervix. The results were as follows. We could classify the cases without white epithelium into microinvasive cancer and carcinoma in situ according to elevation or hollowness and roughness and the cases with I grade white epithelium (thin white epithelium) into severe dysplasia and mild or moderate dysplasia according to the existence of elevation, roughness, II type vessels and elevation of gland opening. Among the cases with II grade white epithelium (thick white epithelium) those without roughness, II type vessels and increased gland opening were mild or moderate dysplasia and most case with III or IV type vessels were microinvasive cancer. We concluded that more than half of the cases without III or IV type vessels spread to transverse pollution of white epithelium and lack or indefiniteness of gland opening, severe dysplasia with 0 finding, carcinoma in situ with 1 or 2 finding and microinvasive cancer with 3 findings. With these criteria, we were able to obtain high (93.4% with mean) correct diagnostic ratios.

Carcinoma in Situ↗