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Biomedical subjects

H Saeki

Publications and source records attributed to H Saeki.

At least 199 records · Page 11Linked to original sources
PubMed1975

Synthesis of aminotrideoxybutirosin A, a chemically modified antibiotic active against butirosin-resistant bacteria.

5"-Amino-3',4'5"-trideoxybutirosin A (4) was synthesized by two routes starting from the known tri-O-acetyl-tetra-N-benzyloxycarbonyl-3",5"-O-cyclohexylidene-3',4'-di-O-mesylbutirosin A (5). Introduction of amino function at C-5" was carried out by displacement of 5"-tosyloxy group with sodium azide either before or after 3',4'-deoxygenation. Compound 4 shows outstanding activities against strains including Pseudomonas aeruginosa and Escherichia coli which are highly resistant to butirosin and 5"-amino-5"-deoxybutirosin A (2).

Anti-Bacterial Agents↗
PubMedDate not supplied

A new and efficient method to generate human IgG monoclonal antibodies reactive to cancer cells using SCID-hu mice.

Human monoclonal antibodies (mAbs) are very useful for treatment of cancer, but they are difficult to obtain since immunization of humans is not a practical proposition at present. As an approach to circumvent this problem, we have simultaneously inoculated cancer tissues and regional lymph node cells obtained from lung cancer patients into SCID mice to allow in vivo stimulation of human lymphocytes against autologous cancer tissues. Human immunoglobulins, especially IgG, were observed in the SCID-hu sera, and some showed high reactivity to lung cancer cell lines. Testing of human B-lymphoblastoid cell lines obtained from SCID-hu spleen and thymus for antibody activity revealed 16-45% of them to be reactive to lung cancer cells. These percentages are high as compared with previous reports. Furthermore, we could establish 4 human IgG mAbs reactive to lung cancer cell lines. These results indicate successful stimulation of specific human lymphocytes in vivo, which thereby enables efficient generation of human monoclonal antibodies using SCID-hu mice.

Adenocarcinoma↗
PubMedDate not supplied

Clinicopathologic features of patients with oesophageal cancer obtaining a histological complete response for preoperative hyperthermo-chemo-radiotherapy.

From 1979 to 1993, 151 patients with resectable oesophageal cancer underwent preoperative hyperthermo-chemo-radiotherapy (HCR) followed by a subtotal esophagectomy. All resected specimens were histopathologically evaluated, and then were classified into two groups according to the efficacy of the preoperative HCR. Group A included 33 patients whose resected oesophagus was free of any cancer cells (grade 3). Group B included 118 patients, in which viable cancer cells remained in the resected specimens to various degrees (grade 1,2). The incidence of patients with well differentiated squamous cell carcinoma, node negative cases, or TNM stage I/II was significantly higher in group A than in group B (27.3% versus 9.3%, 72.7% versus 50.8%, 72.7% versus 50.8%, respectively). The recurrence rate was 33.3% (11/33) in group A, while it was 65.3% (77/118) in group B (p < 0.005). There was no case with any local recurrence in the former, while it was 8.5% (10/118) in the latter. The 1-, 3- and 5-year survival rates were 87.2%, 65.9% and 46.1% in group A, while they were 54.8%, 26.7% and 18.8% in group B (p < 0.005), respectively. Preoperative HCR may be expected of decreasing in the recurrence rate, including regional relapse when a grade 3 is obtained. Complete local control would further positively influence the prognosis.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Relationship between the expression of HLA-DR antigen and the effectiveness of preoperative hyperthermo-chemo-radiotherapy in oesophageal cancer.

Based on the hypothesis that tumour cells expressing HLA-DR antigen would easily be damaged by the local immune response during preoperative treatments, the relationship was investigated between the expression of HLA-DR antigen in the oesophageal cancer and the effectiveness of the preoperative treatment. Immunohistochemical staining for the detection of HLA-DR antigen in cancer cells from biopsy specimens obtained before undergoing preoperative hyperthermo-chemo-radiotherapy (HCR therapy) in patients with oesophageal squamous cell carcinoma was performed, and the relationship between the expression of HLA-DR antigen and the effectiveness of HCR therapy was evaluated according to a histopathologic examination of resected specimen. A total of 35 cases were examined in which 14 showed strongly positive staining (+2), 14 weakly positive staining (+) and seven negative staining (-). No significant differences in the clinicopathologic factors between the groups were observed. In the 14 strongly positive HLA-DR antigen cases, nine were markedly effective (grade 3) (64.3%), four were moderately effective (grade 2) (28.6%) and one was slightly effective or ineffective (grade 1, 0) (7.1%). In the 14 weakly positive HLA-DR antigen cases, the markedly, moderately and slightly or ineffective cases numbered four (28.6%), eight (57.1%) and two (14.3%), respectively. On the other hand, in the seven patients showing no HLA-DR expression, the markedly, moderately and slightly effective cases numbered one (14.3%), two (28.6%) and four (57.1%), respectively. A statistical difference was observed between the cases of strongly positive and negative staining for HLA-DR antigen (p < 0.05). The expression of HLA-DR antigen in oesophageal cancer cells is thus considered to potentially be a valuable factor for predicting the effectiveness of preoperative treatment.

Aged↗
PubMedDate not supplied

Preoperative therapy with insufficient effectiveness is related to unfavorable prognosis of patients with esophageal squamous cell carcinoma.

The disadvantage brought by the preoperative therapy with insufficient effectiveness for the patients with esophageal carcinoma has not been previously investigated. The aim of the current study was to show that the prognosis of patients with advanced esophageal carcinoma treated with preoperative therapy with insufficient effectiveness may be rather more unfavorable than that of patients without preoperative therapy. The subjects were 406 patients with esophageal squamous cell carcinomas of depth reaching to muscularis propria or adventitia but not to neighboring structures, who had been treated with esophagectomy and reconstruction. Although the proportions of lymphatic invasion and venous invasion in patients treated with preoperative therapy of insufficient effect were lower than those of patients without preoperative therapy, the 1-, 3- and 5-year survival rates in the former (62.2%, 32.0% and 23.1%, respectively) was significantly lower than in the latter (78.5%, 57.3% and 39.7%, respectively, p=0.01). A preoperative therapy with insufficient effectiveness may bring a more unfavorable prognosis of patients with esophageal squamous cell carcinoma.

Carcinoma, Squamous Cell↗