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Biomedical subjects

K Kawabata

Publications and source records attributed to K Kawabata.

At least 73 records · Page 4Linked to original sources
PubMed2000

[Treatment strategy for cervical node metastasis from squamous cell carcinoma of the oropharynx].

The purpose of this study is to ascertain the role of neck surgery and radiation therapy for cervical lymph node metastasis in oropharyngeal cancer patients. We reviewed 217 previously untreated patients with squamous cell carcinoma of the oropharynx who were treated at the Cancer Institute Hospital in Tokyo between 1971 and 1995. The N stage distribution was; N0: 83(38.2%), N1: 42(19.4%), N2a: 23(10.6%), N2b: 27(12.4%), N2c: 33(15.2%), and N3: 9(4.2%). A predominance of cervical node metastases in level II and III was revealed and there were no skip metastases outside of level II and III. The control rate of cervical metastasis for each N stage was; N0: 96.9%, N1: 90.0%, N2a: 76.5%, N2b: 62.5%, N2c: 50.0%, and N3: 0%. Definitive irradiation provided sufficient treatment for small nodes, when the primary tumor growth was well controlled by radiation therapy. Neck dissection was necessary for more advanced neck metastases. Selective limited neck dissection (level II and III) is recommended for N0 and N1 patients, and modified or classical RND is considered to be better for most cases with N2 and N3.

Adult↗
PubMed2000

[Ultrasonographic evaluation of metastatic cervical lymph nodes in head and neck cancers].

This study evaluates the use of ultrasonography (USG) to diagnose metastatic cervical lymph nodes. Three-hundred and one lymph nodes were removed from 58 patients with squamous cell carcinomas of the head and neck. None of the patients had received any preoperative treatments for cancer. The lymph nodes were then histopathologically examined: 139 metastatic lymph nodes and 162 non-metastatic nodes were found. USG was then used to evaluate the size, internal echo, and margin of each lymph node. Size was found to be the best criteria for distinguishing metastatic lymph nodes from non-metastatic lymph nodes in all cervical regions (78% accuracy). Superior internal jugular lymph nodes and submandibular lymph nodes larger than 7 mm and mid and inferior internal jugular lymph nodes larger than 6 mm were regarded as metastatic. Internal echoes were classified into five patterns: homogeneous hypoechoic, homogeneous hyperechoic, heterogeneous, eccentric hyperechoic, and centric hyperechoic. Homogeneous hyperechoic and heterogeneous patterns were characteristic of metastatic nodes, while eccentric hyperechoic patterns were characteristic of non-metastatic nodes. Homogeneous hypoechoic patterns were observed in both metastatic and non-metastatic nodes. Regular margins were found in 81% of the metastatic nodes. Of the 22 lymph nodes with irregular margins, however, 91% were metastatic. Evaluations using a combination of USG and clinical feature criteria were compared with evaluations using only thickness as a criterium. Although thickness is the single most important factor in diagnosing metastatic nodes, the combination of USG and clinical feature criteria improved the accuracy of diagnosis to 83%. Thus, diagnostic methods involving a combination of several criteria are more accurate than methods involving only a single criterium.

Carcinoma, Squamous Cell↗
PubMed2000

Suppression of N-nitrosomethylbenzylamine-induced rat esophageal tumorigenesis by dietary feeding of auraptene.

The modifying effects of auraptene on N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumorigenesis were investigated in male F344 rats. At 5 weeks of age, all animals, except those with the test chemical alone and control rats, received s.c. injections of NMBA (0.5 mg/kg body weight/injection, three times per week) for 5 weeks. At the end of the study (20 weeks), 75% of the rats treated with NMBA alone had esophageal neoplasms (papillomas). However, the groups who received a dose of 500 ppm auraptene during the initiation phase developed significantly reduced incidence of tumors (39%; P<0.05). Exposure to auraptene (500 ppm) during the post-initiation phase also decreased the frequency of the tumors (29%; P<0.01). The reduction of the incidence of severe dysplasia was obtained when auraptene was administered in the post-initiation phase (P<0.05). Cell proliferation in the esophageal epithelium determined by proliferating cell nuclear antigen (PCNA) was lowered by auraptene (P<0.01). Blood polyamine contents in rats who received NMBA and the test compound were also smaller than those of rats that received the carcinogen (P<0.05). These findings suggest that dietary auraptene is effective in inhibiting the development of esophageal tumors by NMBA when given during the initiation as well as post-initiation phases, and such inhibition is related to suppression of cell proliferation in the esophageal epithelium.

Animals↗
PubMed1999

Chemopreventive effect of dietary flavonoid morin on chemically induced rat tongue carcinogenesis.

The modifying effects of dietary exposure of the flavonoid morin on 4-nitroquinoline 1-oxide (4-NQO)-induced tongue tumorigenesis, the activities of phase II detoxifying enzymes glutathione S-transferase (GST) and quinone reductase (QR) in liver and tongue, and cell proliferation activity in tongue were investigated in male F344 rats. At 7 weeks of age, all animals except those treated with morin alone and control group were given 4-NQO (20 ppm) in drinking water for 8 weeks to induce oral neoplasms. Starting 7 days before 4-NQO exposure, experimental groups were fed experimental diets containing morin (100 and 500 ppm) for 10 weeks ("initiation feeding"). Starting 1 week after the cessation of exposure to 4-NQO, other experimental groups given 4-NQO and a basal diet were given experimental diets for 22 weeks ("post-initiation feeding"). At week 32 week, "initiation feeding" of morin caused a significant reduction in the incidence of tongue carcinoma (by 44-100%). "Post-initiation feeding" with morin also significantly decreased the frequency of tongue carcinoma (by 44%). Morin feeding elevated liver GST and QR activities and GST activity in the anterior portion of tongue. Feeding with morin significantly lowered QR activity of the posterior part of the tongue. Dietary exposure to morin significantly decreased the proliferating cell nuclear antigen-positive index in the posterior portion. Also, morin feeding lowered tongue polyamine levels, especially in the "post-initiation feeding" group. Our results indicate that morin acts as a chemopreventive agent against tongue carcinogenesis induced by 4-NQO through modification of detoxifying enzyme activities and/or cell proliferation activities.

4-Nitroquinoline-1-oxide↗
PubMed1999

Corneomandibular reflex in ALS.

To clarify the diagnostic value of corneomandibular reflex (CMR) in ALS, the authors examined the prevalence of CMR and other pathologic reflexes in 42 patients with ALS and 110 patients with stroke. A total of 30 of 42 ALS patients had positive CMR. Compared with the patients with hemiparesis or pseudobulbar palsy after stroke, the ALS patients showed a significantly higher frequency of CMR but no other pathologic reflexes. CMR is a sensitive indicator of upper motor neuron involvement in ALS.

Aged↗
PubMed1999

A cell-autonomous requirement for CXCR4 in long-term lymphoid and myeloid reconstitution.

Mice lacking the chemokine stromal cell-derived factor/pre-B cell growth stimulating factor or its primary physiological receptor CXCR4 revealed defects in B lymphopoiesis and bone marrow myelopoiesis during embryogenesis. We show here that adoptive transfer experiments reveal a deficiency in long-term lymphoid and myeloid repopulation in adult bone marrow by CXCR4-/- fetal liver cells, although stromal cell-derived factor/pre-B cell growth stimulating factor-/- fetal liver cells yield normal multilineage reconstitution. These findings indicate that CXCR4 is required cell autonomously for lymphoid and myeloid repopulation in bone marrow. In addition, CXCR4-/- fetal liver cells generated much more severely reduced numbers of B cells relative to other lineages in bone marrow. Furthermore, the repopulation of c-kit+ Sca-1(+) linlow/- cells by CXCR4-/- fetal liver cells was less affected compared with c-kit+ Sca-1(-) linlow/- cells. By previous studies, it has been shown that c-kit+ Sca-1(+) linlow/- cells are highly purified primitive hematopoietic progenitors and that c-kit+ Sca-1(-) linlow/- cells are more committed hematopoietic progenitors in mice. Thus, CXCR4 may play an essential role in generation and/or expansion of early hematopoietic progenitors within bone marrow.

Animals↗
PubMed1999

Involvement of cysteinyl leukotrienes in biphasic increase of nasal airway resistance of antigen-induced rhinitis in guinea pigs.

We examined the effect of a specific cysteinyl leukotriene (LT) receptor antagonist, 4-oxo-8-[4-(4-phenylbutoxy)benzoylamino]-2-(tetrazol-5-yl)-4 H-1-benzopyran hemihydrate (pranlukast), on a novel model of allergic rhinitis induced by repeated intranasal ovalbumin challenge in actively sensitized guinea pigs. Repeated intranasal ovalbumin challenge caused a biphasic increase of nasal airway resistance, peaking 0.5 and 4 h after the final challenge. The early-phase response was accompanied by an increase in sneezing and nasal secretion, while that in the late phase was associated with edema and eosinophil infiltration of the nasal mucosa. Analysis of nasal lavage fluid showed that cysteinyl LTs increased in both phases. Pranlukast, when administered 1 h before every ovalbumin challenge, dose-dependently suppressed the increase of nasal airway resistance in the early- and late phase with evidence of histopathological improvements in the late phase. Pranlukast, however, failed to suppress sneezing and nasal secretion. We suggest that cysteinyl LTs play an important role in allergic rhinitis especially in the nasal obstruction due to edema of the nasal mucosa membrane.

Airway Resistance↗
PubMed1999

Effects of protocatechuic acid, S-methylmethanethiosulfonate or 5-hydroxy-4-(2-phenyl-(E)ethenyl)-2(5H)-furanone(KYN-54) on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced pulmonary carcinogenesis in mice.

Modifying effects of dietary exposure of protocatechuic acid (PCA), a natural monophenolic compound, S-methylmethanethiosulfonate (MMTS), an organosulfur compound newly isolated from cauliflower, and 5-hydroxy-4-(2-phenyl-(E)ethenyl)-2(5H)-furanone (KYN-54), a novel retinoidal butenolide compound, on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) (10 micromol, [corrected] single i.p. injection)-induced pulmonary carcinogenesis were examined in female A/J mice. Each of the test chemicals was given in diets during initiation or post-initiation phases (PCA, 1000 ppm; MMTS, 100 ppm; KYN-54, 200 ppm). All of these which had been proved to be chemopreventive mainly in digestive-organs carcinogenesis did not exert any preventive effect in this model when the incidence or multiplicity of pulmonary tumors (adenomas) of mice given NNK and the test chemical at the termination of the experiment (4 months) was compared to that of mice exposed to the carcinogen alone. In contrast, the multiplicity of lung tumors of mice receiving KYN-54 during the post-initiation phase was significantly larger than of the animals with NNK alone (P < 0.05), showing that KYN-54 has a promoting effect on pulmonary carcinogenesis in mice. These data indicate an organotropic activity of these compounds and suggest that candidate compounds for cancer chemoprevention need to be carefully examined for effectiveness in multiple organs by different models.

4-Butyrolactone↗
PubMed1999

Exposure with the environmental estrogen bisphenol A disrupts the male reproductive tract in young mice.

Environmental estrogens (endocrine disruptive chemicals) have been shown to affect reproduction in wild life and it has been reported that maternal exposure with those chemicals have adverse effects on the male reproductive tract. However, little is known about the potential effects of prepubertal or pubertal exposure with environmental estrogens on the male reproductive tract. Here we examine plasma hormone levels and histology in the testis of mice following either 4- or 8-week oral administration of bisphenol A. Plasma free testosterone levels were dramatically decreased following 8 weeks of bisphenol A treatment compared with control group and morphologically multinucleated giant cells having greater than three nuclei were found in seminiferous tubules in the testis following the 8-week bisphenol A treatment. No differences in plasma corticosterone and luteinizing hormone levels were seen between bisphenol A and control groups. Thus, exposure with bisphenol A around pubertal period may directly disrupt the male reproductive tract. These facts suggest that more detailed studies will warrant the assessment of the risk to the developing human testis from exposure to bisphenol A and other environmental estrogens in prepubertal and pubertal period.

Administration, Oral↗
PubMed1999

Paraganglia of the gallbladder: a report of two cases with an immunohistochemical study.

Paraganglionic tissues incidentally observed in the gallbladder are presented. The patients, a 51- and a 55-year-old woman, underwent gallbladder resection for chronic cholecystitis with gallstones. Two and one paraganglionic tissues were observed in the subserosal connective tissue of the two gallbladders, respectively. Immunohistochemically, the chief cells were positive for chromogranin A, and the sustentacular cells were positive for S100 protein. Tyrosine hydroxylase (in two of three), dopamine beta-hydroxylase (in one of three), methionine-enkephalin (in two of three), and leucine-enkephalin (in two of three) were also positive in a small amount of the chief cells. These structures, which slightly resembled adrenal medulla or retroperitoneal paraganglia, might be misunderstood as an infiltration of primary or metastatic carcinoma into the subserosal connective tissue.

Cholecystitis↗
PubMed1999

New classification of stage IV squamous cell carcinoma of the oropharynx.

OBJECTIVE: The recent progress in reconstructive surgery for the treatment of head and neck carcinomas has made it possible to radically resect cancers. However. the choice of treatment for oropharyngeal carcinoma is rather difficult. Radical treatment sometimes results in severe complications, suggesting that some modes of treatment might reduce the quality of life. The 5-year survival rate of patients with stage IV oropharyngeal carcinoma is still very poor. It is necessary to re-classify stage IV squamous cell carcinoma of the oropharynx in relation to the prognosis. Foote et al. (Base of tongue carcinoma: patterns of failure and predictors of recurrence after surgery alone. Head Neck 1993:15:300-307) demonstrated the two subgroups of stage IV oropharyngeal squamous cell carcinoma, as favorable stage IV and unfavorable stage IV. In this study, we have re-examined the validity of these subsets and we have demonstrated the new subsets of stage IV squamous cell carcinoma of the oropharynx. METHODS: We have examined 221 cases of oropharyngeal squamous cell carcinoma at the Cancer Institute Hospital in Tokyo between 1971 and 1994. A total of 107 cases of stage IV were included. We analyzed these cases retrospectively. RESULTS: Based on the subsets demonstrated by Foote et al., there were no significant differences between the two groups in our cases, suggesting that these subsets were not useful for the choice of the treatment. In order to make a new classification in view of better choice of treatment, either radical treatment or palliative therapy, these cases were divided into two new groups of stage IV. one group with relatively good results (T1-3 N2 M0 and T4 NO-1 M0; new favorable stage IV), and the other with very poor results (any-T any-N M1 and any-T N3 M0 and T4 N2 M0; new unfavorable stage IV). Patients with the new favorable stage IV have a 5-year survival rate of 30.4%, and those with the new unfavorable stage IV had a survival rate of 0%. CONCLUSION: These new subsets of stage IV can be directly related to the prognosis, and are therefore useful in the choice of treatment.

Carcinoma, Squamous Cell↗
PubMed1999

Multi-institutional randomized clinical study on the comparative effects of intracavital chemotherapy alone versus immunotherapy alone versus immunochemotherapy for malignant effusion.

The current prospective randomized study was designed to compare the effects of intracavitary (i.c.) chemotherapy vs immunotherapy vs immunochemotherapy for malignant effusion. Between 1992 and 1995, a total of 42 patients with malignant effusion were registered, and 41 patients were eligible for statistical analysis. The primary diseases of the eligible patients included 27 gastric, four colorectal, four pancreatic, three lung, two liver and one oesophageal cancers. The patients with malignant effusion were randomly assigned into one of three i.c. therapeutic regimens: chemotherapy alone with weekly injection of anticancer agents (ACAs: cisplatin, mitomycin-C, adriamycin, etc.) (Group A, n = 13); immunotherapy alone with weekly injection of streptococcal preparation OK-432 (Group B, n = 14); or immunochemotherapy with ACAs and OK-432 (Group C, n = 14). The response of the effusion, patient survival and the kinetics of cytokines in the effusion were compared. There were no differences in the patients' backgrounds. The side-effects of the regimens included pain, anorexia, fever, leucopenia and anaemia and there were no differences in their incidence among the three groups. One patient died after cisplatin (CDDP) administration in Group A. Cytologic examination revealed that tumour cells in the effusion disappeared in 23% of Group A cases, 36% of Group B cases and 36% of Group C cases. The malignant effusion did not disappear in any of the Group A cases; however, the effusion disappeared in 29% of Group B cases and 43% of Group C cases (P = 0.03, Group A vs Group C). Furthermore, the 50% survival period was 1.6 months for Group A, 2.4 months for Group B and 3.5 months for Group C. The 6-month survival rate was 7% for Group A, 6% for Group B and 34% for Group C, and the 1-year survival rate was 0%, 0% and 17% respectively (P = 0.048, Group A vs Group C by the log-rank test). The analysis of the cytokine kinetics revealed a prominent increase in the level of interleukin-6 in the effusion in Group C. These results suggest that i.c. immunochemotherapy with OK-432 and ACAs may be more beneficial than i.c. chemotherapy alone or immunotherapy alone.

Adjuvants, Immunologic↗