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Biomedical subjects

N Ohta

Publications and source records attributed to N Ohta.

At least 163 records · Page 9Linked to original sources
PubMed1993

Risk of internal mammary lymph node metastases and its prognostic value in breast cancer patients.

The risk of an internal mammary lymph node (IMN) metastasis and its prognostic value for patients with invasive breast cancer were assessed by evaluating 142 patients who had either a mastectomy with lymph node dissection or a biopsy of the IMN. By univariate analysis, overall survival significantly correlated with the patient's age, clinical axillary node status, tumor size, and DNA ploidy, as well as histologically confirmed axillary and IMN metastases. By multivariate analysis, however, only the presence of axillary and IMN metastases appeared to be an important independent factor affecting survival. However, the incidence of IMN metastases was associated significantly with age, clinical tumor and axillary node status, tumor size, axillary lymph node metastases, and DNA ploidy. Accordingly, the patient's age, tumor size, DNA ploidy, and axillary lymph node metastases proved to be effective variable for discrimination. Consequently, in predicting the presence of IMN metastases, a diagnostic accuracy of 82%, a sensitivity of 84%, and a specificity of 82% can be achieved by a discriminant function. We conclude that the discriminant function with these four variables is effective in assessing the risk of IMN metastases.

Aneuploidy↗
PubMed1993

A comparison of breast cancers detected by mass screening and those found in out-patient clinics.

We evaluated the results of a mass screening study on breast cancer detection by physical examination alone conducted in Ishikawa Prefecture from 1978 to 1990. The number of cases of breast cancer detected by mass screening was then compared with that found in out-patient clinics during the same period. Breast cancer was detected in 88 of 152,969 women by mass screening, the detection rate being 0.06% for the total study: 0.08% at the initial screening and 0.04% at periodic screenings. Early stage breast cancer was more frequently detected during periodic screenings than at the initial screening or in out-patient clinics. Moreover, although the initial screenings may have identified patients with breast cancer at more advanced stages, the survival was not significantly different. The results of this series led us to conclude that mass screening by physical examination alone may have no impact on the mortality rate of breast cancer.

Adult↗
PubMed1993

A retrospective study on the clinical and biological prediction of axillary lymph node metastasis in breast cancer.

If axillary lymph node metastases were able to be accurately predicted, dissection could be avoided in some patients with breast cancer whose axillary nodes are clinically negative. In this study, we assessed the relationships between histological axillary lymph node metastases and clinical axillary nodal status, tumor size, DNA-ploidy, c-erbB-2 expression, and the score of the argyrophilic nucleolar organizer region. We then attempted to evaluate their predictive values for axillary lymph node metastasis in 173 patients with invasive breast cancer, retrospectively. The clinical and biological variables were significantly correlated with the presence and degree of axillary lymph node metastases. A metastatic index, calculated from the clinical and biological variables, proved especially useful for predicting axillary lymph node metastases in patients whose axillary nodes were clinically negative. However, the predictive abilities were still limited and thus it was concluded that as yet, only axillary dissection can provide accurate information on axillary lymph node metastases.

Adult↗
PubMed1993

The psychological and cosmetic aspects of breast conserving therapy compared with radical mastectomy.

An evaluation of the psychological and cosmetic morbidity of 31 patients who had undergone breast conserving treatment (BCT group) and 71 patients who had undergone radical mastectomy (RM group) revealed that 85% and 73%, respectively, were satisfied with their operative results. BCT appeared superior to RM in relation to body image, with 93% of the BCT group indicating BCT as a future choice of treatment, whereas only 35% of the RM group indicated RM as a future choice of treatment. For 59% of the BCT patients, the results were considered excellent or good by a physician, but fear of recurrence was frequently expressed by both groups even though an early stage of breast cancer had been significantly more common in the BCT group than the RM group. Sexual adjustment was the same in both groups. Body image was thus concluded to have been improved by BCT rather than RM, but psychological morbidity was essentially the same in both groups.

Adaptation, Psychological↗
PubMed1993

Influence of hormones on tumor growth, cell kinetics, estrogen receptor and insulin-like growth factor-I-related protein of human breast cancer (MCF-7) cells transplanted in nude mice.

The influence of estrogens and tamoxifen on estrogen receptor (ER)-positive human breast cancer (MCF-7) cells transplanted into athymic nude mice was investigated. The mice were divided into the following three groups: (1) an E2 group with mice receiving 17 beta-estradiol dipropionate; (2) a TAM group with mice receiving tamoxifen; (3) a control group with mice given no hormone. (1) Tumor growth was significantly increased in the E2 group, but significantly decreased in the TAM group compared to control; (2) the tumor contents of insulin-like growth factor-I (IGF-I) and the rate of IGF-I-positive cells were significantly lower in the E2 group, but significantly higher in the TAM groups compared to control; (3) the IGF-I-positive cell rates were in significant inverse correlation with the [3H]thymidine-labeled cell rates in the E2, TAM and control groups. Thus, the tumor contents of IGF-I and the rate of IGF-I-positive cells were inversely correlated to the tumor growth and the [3H]thymidine-labeled cell rate in this in vivo study, although IGF-I is known to be a mitogen for breast cancer cells in vitro. Further studies are necessary to answer the questions as to the in vivo roles of immunoreactive IGF-I in ER-positive breast cancer.

Animals↗
PubMed1993

Clinical and biological prediction of axillary and internal mammary lymph node metastases in breast cancer.

We assessed the relationships among histological axillary (AX) or internal mammary (IM) metastases and clinical and biological variables, and then attempted to evaluate their predictive values for AX and IM metastases in 128 patients with invasive breast cancer. As the results, these clinical and biological variables were significantly correlated with AX and IM metastases. However, a metastatic index calculated from clinical and biological variables was not much better in prediction of the AX metastases than axillary nodal status, whereas it was useful to predict the IM metastases. Thus, the predictive ability was still limited. Since accurate prediction of AX and IM metastases is critical to therapeutic choice, however, further study would be required.

Adult↗
PubMed1993

Mastectomy with and without immediate breast reconstruction using a musculocutaneous flap.

We compared surgical cosmetic results in 83 patients who underwent mastectomy with immediate breast reconstruction (MIBR) using a myocutaneous flap with those of 153 patients with breast cancer who underwent mastectomy without breast reconstruction. Cosmetic results were significantly better in patients who underwent MIBR than radical mastectomy or extended MIBR, although no intergroup difference existed in the reconstructive technique. Neither did any difference exist in the incidence of complications between patients undergoing MIBR and mastectomy without breast reconstruction, or between patients undergoing modified mastectomy and radical or extended mastectomy. Finally, MIBR did not appear to adversely effect recurrence or overall survival. We conclude that MIBR using a myocutaneous flap is an acceptable treatment option for patients with breast cancer.

Adult↗
PubMed1993

Further analysis of predictive value of Helix pomatia lectin binding to primary breast cancer for axillary and internal mammary lymph node metastases.

We investigated the relation between Helix pomatia (HPA) staining of primary breast cancer and the presence of axillary (AX) or internal mammary (IM) metastases, and evaluated its predictive value for AX or IM metastases in comparison with the use of clinical variables. There was a significant association between the HPA staining and AX or IM metastases. When HPA staining was regarded as an indicator of AX metastases, a diagnostic accuracy of 72%, a sensitivity of 69% and a specificity of 75% were achieved. As an indicator of IM metastases, these values were 64%, 76% and 62%, respectively. In predicting the presence of AX metastases using a discriminant function with clinical AX status, location of tumour and tumour size, diagnostic accuracy, sensitivity and specificity were 79%, 69% and 87%, respectively. In predicting the presence of IM metastases using the discriminant function with clinical AX status and tumour size, these values were 74%, 71% and 75%, respectively. Therefore, it was concluded that the HPA staining may be useful, but it was equivalent with the discriminant function with clinical variables in prediction of AX or IM metastases.

Analysis of Variance↗
PubMed1993

Clonal analysis of human T-cell responses to fractionated house dust mite antigens (Dermatophagoides pteronyssinus).

In the present study, we investigated the cellular basis of house dust mite-driven immune responsiveness in an atopic individual with perennial rhinitis. We established 40 human T-cell clones (CD3+, 4+, 8-) reactive to Dermatophagoides pteronyssinus (Dp) antigen under the restriction of HLA-DR. By using the crude Dp antigen and its 14 molecular weight (MW) fractions, we analyzed the distribution of T-cell-recognizing sites in the whole Dp extract. We tested T-cell-mediated immunity through two parameters; the identification of Dp fractions inducing T-cell proliferation, and the ability of T-cell clones to secrete IL-2, IL-4, and IFN-gamma. According to a prominent peak among fraction-driven T-cell proliferation, we observed that T-cell clones that recognized 45,000- to 95,000-MW fractions were common, while clones reactive to 15,000- to 25,000-MW fractions were less frequent. Several clones were also reactive to antigens of Dermatophagoides farinae or other insects. Based on the responses of cloned T cells, we observed at least 9 distinct T epitopes in crude Dp antigen. These T-cell clones had a heterogenous secretory pattern of cytokines. T-cell clones showed no association between their ability to produce regulatory cytokine and their recognition of particular Dp fractions.

Adult↗
PubMed1993

Alteration of fibrinogen secondary structure by cis-diamminedichloroplatinum(II) and calcium protection.

The structural alteration of human fibrinogen (Fbg) by cis-diamminedichloroplatinum(II) (cis-DDP) was investigated using intrinsic fluorescence and circular dichroism (CD) spectra. In a preceding report, incubation of Fbg with cis-DDP under physiological conditions resulted in the cleavage of disulfide (S-S) bonds (N. Ohta, T. Yotsuyanagi and K. Ikeda, J. Pharmacobio-Dyn., 15, 611 (1992)). The intensity of fluorescence for cis-DDP-treated Fbg, in which 6.7 S-S bonds per mol of protein were cleaved, was reduced to 42% relative to native Fbg. CD studies suggested that the alpha-helix content decreased from 42% in its natural state to 29% in the cis-DDP-treated form. The extent of the fluorescence quenching and the decrease in helix correlated with the number of cleaved S-S bonds. The results indicate that cis-DDP leads to a secondary conformational alteration of Fbg involving a structural perturbation of nearby tryptophan residue(s) through S-S bond cleavage. In a buffer containing calcium, however, the smaller fluorescence quenching and the smaller helix decline were observed in cis-DDP-treated-Fbg, even though the same level of S-S cleavage occurred. Calcium binding would protect Fbg in terms of structural alteration as well as S-S cleavage by both dithiothreitol (DTT) and cis-DDP.

Binding Sites↗
PubMed1993

[Clinical experience of simultaneous fiber-urethrocystoscopy and cystometry recording].

We performed fiber-urethroscopy and cystometry recording simultaneously in 15 male patients. Fifteen patients were consisted of 12 complaining of micturition difficulty (such as BPH, NB, BNS) and 3 normal control. Fiberscope, Olympus CYF-1 and BF3C10, and cystometry were connected the DISA system. Firstly, we insert fiberscope from the urethra to bladder careful, and then cystometry recording using carbon dioxide gas started under direct vision of fiberscope. We compared cystometrical parameters based on our original method to these on conventional one. There were slight statistical significances in the pressure at the first desire to void and the maximum desire to void. But these differences as well as the frequently and the size of uninhibited contraction were not induced by the caliber of the urethroscopy. In conclusion, cystometric recording and urethroscopic observation using fiberscope are simultaneously carried out safely without reducing their diagnostic accuracy.

Cystoscopy↗
PubMed1992

A histidine protein kinase homologue required for regulation of bacterial cell division and differentiation.

Differentiation in the dimorphic bacterium Caulobacter crescentus results from a sequence of discontinuous, stage-specific events that leads to the production of a stalked cell and a new motile swarmer cell after each asymmetric cell division. As reported previously, pseudoreversion analysis of mutations in the pleiotropic developmental gene pleC identified three cell division genes: divJ, divK, and divL. We show here that one of these genes, divJ, encodes a predicted protein of 596 residues with an extensive hydrophobic N-terminal region and a C-terminal domain containing all of the invariant residues found in the family of bacterial histidine protein kinases. Our results also show that divJ is discontinuously transcribed early in the swarmer cell cycle during a period that coincides with the G1 to S transition. We propose that the DivJ protein is one member of a signal transduction pathway regulating the cell cycle and differentiation in Caulobacter and that protein modification by phosphorylation may play a central role in coupling developmental events to progress through the cell division cycle.

Amino Acid Sequence↗
PubMed1992

C-erbB-2 oncoprotein expression versus internal mammary lymph node metastases as additional prognostic factors in patients with axillary lymph node-positive breast cancer.

The relationship was assessed between c-erbB-2 oncoprotein expression and other prognostic factors in breast cancer, such as axillary and internal mammary node metastases. The value of these indicators was analyzed in estimating prognosis, especially in patients with axillary node-positive breast cancer. These results showed that c-erbB-2 is significantly related to clinical stage and axillary node metastases. A univariate study revealed that disease-free and overall survival were correlated significantly with clinical stage, tumor size, axillary and internal mammary node metastases, and 21N status. Among the patients with axillary node involvement, however, 21N status did not appear to be a significant additional prognostic factor. Internal mammary node metastases were significant. In a multivariate study, only axillary and internal mammary node metastases were significant prognostic factors for either the entire group of patients or those with positive axillary nodes. Therefore, axillary node dissection and biopsy of the internal mammary nodes may provide important prognostic information for patients with breast cancer.

Adult↗
PubMed1992

Papillary thyroid cancer and its surgical management.

The surgical management in papillary thyroid cancer has been highly controversial. In the Department of Surgery (II), Kanazawa University Hospital, the surgical management especially for cervical lymph node metastases has changed since 1973 from a conservative approach to an aggressive one. In order to determine whether an aggressive approach is warranted, a retrospective multivariate analysis was carried out on 106 cases of papillary thyroid cancer. The patients have been followed for 10-28 years. Multivariate analysis was conducted following Cox's model. By this analysis, aggressive management appeared to have no impact on survival or relapse-free survival. However, age, sex, tumor size, and cervical lymphadenopathy were confirmed to be important prognostic factors in survival and/or relapse-free survival.

Adult↗
PubMed1992

Oncological aspect of immediate breast reconstruction in mastectomy patients.

In this study, we compared the relapse-free and overall survival of 83 patients who underwent mastectomy with immediate reconstruction (MIBR) using a musculocutaneous flap with or without silicone implant with those of 153 patients with breast cancer who underwent mastectomy without immediate reconstruction. In univariate analysis, the overall and/or relapse-free survival of reconstructed patients with four or more positive axillary lymph nodes or those with menopausal status were significantly inferior compared with those of nonreconstructed patients. In multivariate analysis, however, the immediate breast reconstruction did not appear to have a significant adverse influence on all patients, and on the subgroups stratified by menopausal status or axillary lymph node metastases. Therefore, it was concluded that MIBR using a musculocutaneous flap did not compromise the survival of patients with breast cancer.

Adult↗
PubMed1992

Transfection and expression of a gene coding for a human melanoma antigen recognized by autologous cytolytic T lymphocytes.

Human melanoma line MZ2-MEL expresses several antigens recognized by autologous cytolytic T lymphocytes (CTL). As a first step towards the cloning of the gene coding for one of these antigens, we tried to obtain transfectants expressing the antigen. The DNA recipient cell was a variant of MZ2-MEL which had been selected with a CTL clone for the loss of antigen E. It was cotransfected with genomic DNA of the original melanoma line and with selective plasmid pSVtkneo beta. Geneticin-resistant transfectants were obtained at a frequency of 2 x 10(-4). These transfectants were then screened for their ability to stimulate the production of tumor necrosis factor by the anti-E CTL clone. One transfectant expressing antigen E was identified among 70,000 drug-resistant transfectants. Its sensitivity to lysis by the anti-E CTL was equal to that of the original melanoma cell line. When this transfectant was submitted to immunoselection with the anti-E CTL clone, the resulting antigen-loss variants were found to have lost several of the transfected pSVtkneo beta sequences. This indicated that the gene coding for the antigen had been integrated in the vicinity of pSVtkneo beta sequences, as expected for cotransfected DNA.

Antigens, Neoplasm↗
PubMed1992

The relationship between lymph node metastases and DNA-ploidy status as prognostic factors in invasive breast cancer.

We evaluated the relationship between the regional lymph node metastases and the DNA ploidy status in 207 patients with invasive breast cancer, as well as their prognostic values in estimating the prognosis of breast cancer. A significantly higher incidence of aneuploidy was found in patients with a large T3 or T4 tumor, a positive axillary lymph node status, more than 4 positive axillary lymph nodes or positive internal mammary lymph nodes. In a univariate study, the overall survival was significantly correlated with tumor size, axillary lymph node status, axillary and internal mammary lymph node metastases, and DNA ploidy status. In the multivariate analysis, however, only axillary and internal mammary lymph node metastases were recognized as important independent prognostic factors on survival. In this series, the DNA ploidy status did not appear to be an independent prognostic factor either in the entire series or in negative axillary node patients, since it was closely correlated with the axillary or internal mammary lymph node metastases, and the axillary node negative patients had an extremely favorable prognosis.

Adult↗