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Biomedical subjects

K Baba

Publications and source records attributed to K Baba.

At least 109 records · Page 6Linked to original sources
PubMed1993

Expression of Sialyl-Tn antigens in normal squamous epithelium, dysplasia, and squamous cell carcinoma in the esophagus.

Two monoclonal antibodies, TKH2 and B72.3, directed toward the Sialyl-Tn antigen (SA 2, 6GalNAc alpha-O-Ser/Thr), were examined immunohistochemically to analyze the expression of these antigens in 20 areas of normal squamous epithelium, 12 lesions of dysplasia, and 86 cases of squamous cell carcinoma including 32 with superficial carcinoma in the esophagus. No expression of TKH2 or B72.3 was found in the normal squamous epithelium. Among the 12 lesions of dysplasia only one expressed TKH2. In carcinoma the expression of TKH2 and B72.3 was found in 40 (47%) and 21 (24%) of the 86 carcinomas, respectively; however, the number of positive malignant cells with TKH2 and B72.3 totaled less than half that in the tissue, and no relationship was found between either prognosis or lymph node metastasis and the expression of Sialyl-Tn antigen. These results indicate that Sialyl-Tn antigen appears in the process of malignant transformation or tumor progression in esophageal squamous cell carcinoma; however, the positive expression of Sialyl-Tn antigen was not directly connected to either prognosis or lymph node metastasis.

Antibodies, Monoclonal↗
PubMed1993

Surgical treatment of esophageal carcinoma in patients eighty years of age and older.

Before 1979, no patient 80 years of age or older had been operated on at our institution for esophageal cancer, while in the middle period (1980-1984), three patients were operated on, and postoperative pulmonary complications and operative death occurred in 66.7 and 33.3%, respectively. However, in the recent period (1985-1990), there was no postoperative morbidity or mortality in the five cases over age 80. On the other hand, there were 12 patients over age 80 who did not undergo operation, of whom all died of cancer. In the eight operated patients over age 80, two cases are still alive 17 and 34 months after operation. According to the above findings, when the patient's general condition is evaluated to be sufficient to tolerate the operation and the cancer is judged to be resectable, esophageal resection is thought to be indicative in all patients over eighty.

Aged↗
PubMed1993

Calcium control of actin-myosin-based contraction in Triton-treated murine bladder tumor cells.

Using mouse bladder tumor cells (MBT-2 cells) and epithelial cells, the present study evaluated the functional characteristics of the actomyosin system in bladder cancer cells. An immunofluorescence study demonstrated the presence of contractile proteins (actin and myosin) in MBT-2 cells as well as bladder epithelial cells. Triton-treated MBT-2 cells and epithelial cells showed a Ca(2+)-dependent contraction. This was inhibited by N-ethylmaleimide-modified myosin subfragment 1 (NEM-S1), demonstrating that the interaction between actin and myosin is responsible for the contraction of Triton-treated cells. The extent of Ca(2+)-dependent contraction was much greater in MBT-2 cells than in epithelial cells. These results suggest that MBT-2 cells possess a locomotive apparatus consisting of actin and myosin, and that Ca2+ can activate this actomyosin system, leading to the contraction or active locomotory movement of tumor cells.

Actins↗
PubMed1993

Vibrio parahaemolyticus has a homolog of the Vibrio cholerae toxRS operon that mediates environmentally induced regulation of the thermostable direct hemolysin gene.

In an effort to identify the regulatory gene controlling the expression of the tdh gene, encoding the thermostable direct hemolysin of Vibrio parahaemolyticus, we examined total DNA of AQ3815 (a Kanagawa phenomenon-positive strain) for sequences homologous to that of the toxR gene of Vibrio cholerae. The extracted DNA gave a weak hybridization signal under reduced-stringency conditions with a toxR-specific DNA probe. Cloning and sequence analysis of the probe-positive sequence revealed an operon (Vp-toxRS) which was highly similar to the toxRS operon of V. cholerae (Vc-toxRS) (52 and 62% similarities in the two genes, respectively). The deduced amino acid sequences of the Vp-toxRS gene products (Vp-ToxRS) contained regions similar to the proposed transmembrane and activity domains of the Vc-toxRS gene products (Vc-ToxRS). All clinical and environmental strains of V. parahaemolyticus examined possessed the Vp-toxRS genes. In the presence of Vp-ToxS, Vp-ToxR promoted expression of the tdh2 gene, one of two tdh genes (tdh1 and tdh2) carried by Kanagawa phenomenon-positive strains. The DNA sequence located 144 bp upstream of the tdh2 coding region was shown to be important for the Vp-ToxR-stimulated expression of the tdh2 gene in an Escherichia coli background. Comparative analysis of AQ3815 and its isogenic Vp-toxR null mutant gave the following results: (i) Vp-ToxR promoted, in an AQ3815 background, expression of the tdh gene to different degrees in various culture media, with KP broth (2% peptone, 0.5% NaCl, 0.03 M KH2PO4, pH 6.2) being most effective (12-fold); (ii) the promotion of tdh gene expression in KP broth was at the level of transcription; and (iii) Vp-ToxR was essential for demonstration of enterotoxic activity of AQ3815 in the rabbit ileal loop, a model previously used to demonstrate thermostable direct hemolysin-mediated enterotoxic activity of AQ3815. These results demonstrate that Vp-ToxR and Vc-ToxR share a strikingly similar function, i.e., direct stimulation at the transcriptional level of the gene encoding a major virulence determinant (enterotoxin) of a Vibrio species.

Amino Acid Sequence↗
PubMed1993

[Effects of testosterone on smooth muscle in the isolated rabbit corpus cavernosum penis].

It has been reported that there is no relationship between serum testosterone level and erectile function and that testosterone mainly acts on the brain and not on the penis. However, we have found that erectile dysfunction in some patients with low serum testosterone improved after androgen replacement therapy. We therefore studied the effects of testosterone on the contraction and relaxation of the corpus cavernosum penis. Four groups of rabbits were studied over a similar time span. The testosterone group were non-operated and received testosterone propionate 10 mg/day for 14 days before sacrifice. Two groups (castration+testosterone group and castration group) were castrated 28 days before sacrifice. The castration group received sesame oil for 14 days, and the castration+testosterone group received testosterone 10 mg/day for 14 days. Entire penis were removed immediately after death by desanguination and dissected to obtain corpus cavernosum strips. These strips were suspended under 1 g tension in a 20 ml organ bath containing Tyrode's solution. After equilibration for 2 hours, the addition of drugs was started. Changes in tension were monitored with an isometric transducer and recorded. The vasoactive drugs used were norepinephrine bitartrate, 1-phenylephrine hydrochloride, clonidine hydrochloride, acetylcholine chloride and vasoactive intestinal polypeptide. The contractility of the corpus cavernosum strips increased significantly in the testosterone group and the castration + testosterone group, but decreased significantly in the castration group as compared with the control after adding norepinephrine, phenylephrine and clonidine.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Hyperthermo-chemo-radiotherapy for patients with early carcinoma of the esophagus.

Hyperthermia combined with irradiation and chemotherapy (hyperthermo-chemo-radiotherapy) was prescribed pre-operatively for 21 patients with submucosal carcinoma of the esophagus, and its effectiveness was evaluated by a comparison with patients who also had massive submucosal carcinoma, but received no pre-operative treatment (n = 12). There was no difference in the survival rates of these groups (hyperthermo-chemo-radiotherapy group: 3-year survival in 56.6%), but the patients who responded well to the HCR therapy (n = 6) demonstrated better survival rates (3-year survival in 83.3%) than did the patients without any pre-operative treatment (3-year survival in 33.9%). An HCR sensitivity test using the succinate dehydrogenase inhibition test was devised and showed good correlation with the clinical remedial values (the diagnostic specificity was 0.89). An accurate diagnosis of the esophageal lesion and appropriate selection of potentially treatable cases are considered essential for the optimal use of HCR therapy in patients with submucosal carcinoma.

Adult↗
PubMed1993

Endoscopic ultrasonography in the diagnosis of an early esophageal carcinoma.

Patients with epithelial or mucosal carcinoma of the esophagus are considered to have a much better prognosis than those with submucosal carcinoma, although both lesions are classified as superficial carcinomas of the esophagus. With this in mind, we evaluated the usefulness of endoscopic ultrasonography for pre-operatively distinguishing either epithelial or mucosal carcinoma from submucosal carcinoma by comparing the results of endoscopic ultrasonography with the histological findings established in resected specimens. Between 1987 and 1991, 26 patients with no pre-operative treatment were confirmed histologically to have epithelial (2 cases), mucosal (11 cases) or submucosal (13 cases) carcinomas of the esophagus. In 13 patients with epithelial or mucosal carcinoma, 10 were correctly diagnosed with endoscopic ultrasonography (76.9%), while the remaining 3 were overdiagnosed as being submucosal. In 13 patients with submucosal carcinoma, 12 were correctly diagnosed by endoscopic ultrasonography (92.3%), although another case was overestimated. Including one patient with an advanced carcinoma who was underdiagnosed by endoscopic ultrasonography as having a submucosal lesion, the overall accuracy of endoscopic ultrasonography was 81.5% for diagnosing the depth of invasion of a superficial esophageal carcinoma. The above results show that endoscopic ultrasonography can provide surgeons with important information in the pre-operative assessment of a superficial esophageal carcinoma.

Adult↗
PubMed1993

Histopathology of early esophageal carcinoma and squamous epithelial dysplasia.

To examine the histogenesis of esophageal cancer and the pathological relationship between dysplasia and carcinoma of the esophagus, 44 cases of superficial esophageal carcinoma (restricted to within the submucosal layer) who received no pre-operative treatment were reviewed retrospectively. There were 40 dysplastic lesions in 17 cases (38.6%) and epithelial dysplastic lesions were classified into 6 with mild, 17 with moderate and 17 with severe, degrees of dysplasia. Although the continuity of dysplastic lesions with the carcinomatous areas was not frequent (35.0%), it was more often encountered in severe dysplasia than in moderate or mild dysplasia, suggesting some relationship between the severity of dysplasia and carcinoma. In the cases with a dysplastic lesion, multiplicity of squamous cell carcinoma was more frequently seen (p < 0.01), suggesting a multicentric occurrence of dysplastic lesions and carcinomas.

Adult↗
PubMed1993

Carcinomatous invasion and lymphocyte infiltration in early esophageal carcinoma with special regard to the basement membrane. An immunohistochemical study.

We examined 24 cases of superficial esophageal carcinoma and evaluated 94 areas, including 43 intra-epithelial (ep), 36 mucosal (m) and 15 submucosal (sm) areas, using the immunohistochemical staining of laminin to detect the basement membrane. The staining pattern was divisible into three patterns, i.e., continuous, fragmentary and defective. Defective patterns were observed in 14%, 53%, and 73% of the ep, m, and sm lesions, respectively (p < 0.01). With regard to the degree of lymphocyte infiltration, 77% of the continuous areas were accompanied by a low lymphocyte infiltration, while 56% of the defective areas were accompanied by dense infiltrations with follicle formation. Lymphocyte infiltration was thus statistically significantly (p < 0.01) more closely associated with the defective areas than with the continuous areas. Furthermore, urokinase-type plasminogen activator was detected immunohistochemically in 11.1% of the defective areas, and in none of the continuous areas. These findings suggested 1) that superficial esophageal carcinoma might progress while destroying the basement membrane, and 2) that as host immune reactions lymphocytes might infiltrate the lesions where the basement membranes were destroyed and cancer cells exposed to the underlying layer. The findings also suggested the possibility that the degradation of the basement membrane might be caused by proteolytic enzymes produced by cancer cells.

Adult↗
PubMed1993

DNA ploidy as a prognostic factor in early esophageal carcinoma.

Cell nuclear DNA content was cytophotometrically determined in biopsy specimens obtained from thirty-five patients with superficial esophageal carcinoma. The relationship between the DNA distribution pattern and histopathological features, prognosis and postoperative survival time was then investigated. Patients with a low ploidy pattern had a more favorable postoperative course, with 62% attaining a 5-year survival rate, than those with high ploidy, of whom 34% attained a 5-year survival rate (p < 0.01). The recurrence rate was higher for the high ploidy pattern (64.3%) than for the low ploidy pattern (35.3%). Moreover, the rate of recurrence within 2 years was 50% in high ploidy, which was higher than the 5.9% rate in the case of low ploidy (p < 0.05). Although there was no clearly established relationship between the DNA distribution pattern and clinicopathological features, a multivariate analysis revealed that the DNA distribution pattern was one of the independent and significant prognostic factors of superficial esophageal carcinoma. These results thus suggest the usefulness of a preoperative DNA analysis of biopsy specimens in predicting the prognosis and determining perioperative therapeutic strategy for both superficial esophageal carcinoma and for advanced cases.

Adult↗
PubMed1993

[A case of successful surgical treatment for bilateral pulmonary arteriovenous fistulas].

A 55-year-old man was admitted to our hospital with chief complaints of exertional dyspnea and chest x-ray abnormalities. On physical examinations, clubbing and systolic murmur were detected. The patient's hemoglobin rose to a level of 19.0 g/dl, with a rise in hematocrit to 58.8%. While the patient was breathing room air, the PaO2 was 52.8 mmHg, the PaCO2 33.3 mmHg and the pH 7.43. In chest x-ray film, oval well-margined 38 x 30 mm density with enlarged afferent and efferent vessels in the left upper lobe (lts4) and 15 x 13 mm "coin lesion" in the right lower lobe (rts7) were observed. Pulmonary angiography demonstrated that these lesions were arteriovenous fistulas. In cardiac catheterization, an estimated right to left shunt of 31.1% was calculated. Because of the exertional dyspnea and the large shunt, a segmentectomy of the lingula and a wedge resection of the rts7 were simultaneously performed. After the treatment, exertional dyspnea, hypoxia and polycythemia disappeared. As far as we know, this patient is one of the most elderly patients in Japan to be successfully treated surgically for bilateral pulmonary arteriovenous fistulas.

Age Factors↗
PubMed1993

Mediastinal drainage prevents fatal pyothorax from anastomotic leakage after intrathoracic anastomosis in reconstruction for carcinoma of the esophagus.

In our experience, anastomotic leakage occurred in five of 69 patients with intrathoracic anastomosis after resection of carcinoma of the esophagus. In the early period, only an ordinary right thoracic drain was put in place, and when leakage occurred, two patients died because of pyothorax, while one patient was saved by surgical drainage. However, in the recent period, in addition to the ordinary right thoracic drain, another drain has also been placed just distal to the anastomosis through the esophageal hiatus through the abdominal cavity, exiting the abdominal wall. After such procedure, drainage has been adequate without any occurrence of pyothorax, even when anastomotic leakage occurred, as in the two most recent instances. Therefore, unless drainage is inadequate and surgical drainage is indicated, as in instances of necrosis of substitutes, mediastinoabdominal drainage seems to be effective in the treatment of intrathoracic anastomotic leakage.

Aged↗
PubMed1993

[A case of chondrosarcoma of the thoracic vertebra].

A case of chondrosarcoma of the thoracic vertebra in a 47-year-old female is described. Chest X-ray, CT and MRI disclosed an abnormal mass lesion in the posterior mediastinum. The lesion was surgically removed through right thoracotomy. The operative findings revealed that the lesion, hard and measuring 6.5 x 4.5 x 4.5 cm in diameter, was originated from the 7th and 8th thoracic vertebra. The lesion was histopathologically diagnosed chondrosarcoma. The chondrosarcoma arising from the thoracic vertebra is very rare, and only 10 cases have hitherto been reported in the Japanese literature.

Chondrosarcoma↗
PubMed1993

[Intracavernous injection of lipo prostaglandin E1 for the diagnosis of impotence: a comparative study with prostaglandin E1-CD].

Intracavernous injection of 20 micrograms prostaglandin E1-CD (PGE1-CD, 8 cases), 5 micrograms lipo prostaglandin E1 (Lipo PG-E1, 8 cases) or 10 micrograms Lipo PGE1 (9 cases) was performed in patients with functional impotence in order to comparatively analyze the diagnostic efficacy of these drugs. Full erection was observed in all patients who received intracavernous injection of 20 micrograms PGE1-CD or 10 micrograms Lipo PGE1. However, full erection was observed in 4 out of 8 patients administered 5 micrograms Lipo PGE1. RigiScan was used on all patients, and latency until erection (achievement of maximum rigidity of the base) after injection, maximum rigidity of the penile tip and base and circumferential expansion rate of the penile tip and base were measured. With regard to these RigiScan data and duration of erection, there were no significant differences among the 3 groups. There were no severe side effects in any of the patients. These findings indicate that 10 micrograms Lipo PGE1 and 20 micrograms PGE1-CD have similar effects and that Lipo PGE1 may be an effective drug for the diagnosis and treatment of impotence.

Adult↗
PubMed1992

Effect of stilbene derivatives on gastric H+, K(+)-ATPase.

The effect of naturally occurring hydroxystilbene, 3,3',4,5-tetrahydroxystilbene (piceatanol), and its derivatives on gastric H+, K(+)-ATPase was studied. Piceatanol inhibited H+, K(+)-ATPase in a dose-dependent manner. The 50% inhibition value was 4.3 x 10(-6) M. It was found from the kinetic study that the inhibition of the enzyme by piceatanol was competitive with respect to ATP and was noncompetitive with respect to K+. Piceatanol also effectively inhibited gastric acid secretion. However, methylation of phenolic hydroxy groups of piceatanol resulted in a complete loss of inhibition of the enzyme and acid secretion, suggesting the role of phenolic hydroxy groups in the inhibition. The study on hydroxystilbene derivatives also showed that phenolic hydroxy groups are important in the interaction with H+, K(+)-ATPase and that stilbenes with neighbouring hydroxy groups are the most effective inhibitors.

Adenosine Triphosphate↗
PubMed1992

Detection of human papillomavirus DNA in esophageal carcinoma in Japan by polymerase chain reaction.

BACKGROUND: Human papillomaviruses (HPV) have been implicated strongly in the pathogenesis of human squamous cell carcinomas, especially of anogenital carcinomas. Some pathologic changes of the esophagus may be one of the candidates for HPV etiology, but the role of HPV infections in the carcinogenesis of the esophagus remains to be clarified. METHODS: To elucidate the association of HPV with carcinogenesis of the esophagus, 45 biopsy samples of esophageal squamous cell carcinomas were examined for the presence of HPV DNA by polymerase chain reaction (PCR). Primers for PCR were (1) consensus primers (CP) for the simultaneous amplification of the E6-E7 regions of cancer-associated HPV types (HPV 16, 18, 31, 33, 52b, and 58), which have been shown to have transforming activities; (2) type-specific primers (SP16, SP18) for the E7 regions of HPV 16 and HPV 18, respectively; and (3) general primers (GP) for the simultaneous amplification of the L1 regions of HPV 6, 11, 16, 18, 31, and 33. RESULTS: PCR using CP first was done for screening and showed that 3 (6.7%) of 45 specimens contained HPV 16 or HPV 18 DNA, the oncogenic high-risk HPV types. This was confirmed by SP16 and SP18 PCR. However, no HPV DNA was detected by PCR using GP. These results suggested that the HPV DNA detected might be integrated into the cell genome with their transforming genes retained and their late regions deleted. CONCLUSIONS: Most oncogenic types of HPV (HPV 16 and HPV 18) were detected by PCR in carcinomas of the esophagus. Thus, HPV might play a role, although at a low frequency, in carcinogenesis of the esophagus.

Base Sequence↗
PubMed1992

Inhibition of gastric H+,K(+)-ATPase and acid secretion by cassigarol A, a polyphenol from Cassia garrettiana Craib.

The effects of cassigarol A, a naturally occurring polyphenol, on gastric H+,K(+)-ATPase and gastric acid secretion were studied. Cassigarol A inhibited H+,K(+)-ATPase and K-stimulated p-nitrophenyl phosphatase from hog gastric mucosa with 50% inhibition of 1.2 x 10(-6) and 6.3 x 10(-6) M, respectively. The kinetic study showed that the inhibition of H+,K(+)-ATPase by cassigarol A was competitive with respect to ATP and non-competitive with respect to K+. Cassigarol A inhibited both H+,K(+)-ATPase-mediated proton transport and 2-deoxy-D-glucose-induced acid secretion. On the other hand, cassigarol A acetate, in which phenolic hydroxy groups are acetylated, was not effective in the inhibition of enzyme activity and acid secretion. These results indicate that cassigarol A is a potent inhibitor of gastric H+,K(+)-ATPase, that the anti-secretory activity of cassigarol A is related to the inhibition of H+,K(+)-ATPase and that an important moiety of cassigarol A in the interaction with the enzyme is the phenolic hydroxy groups.

Adenosine Triphosphatases↗