Biomedical subjects

T Dohi

Publications and source records attributed to T Dohi.

183 records · Page 11Linked to original sources

PubMedDate not supplied

Different binding properties of three monoclonal antibodies to sialyl Le(x) glycolipids in a gastric cancer cell line and normal stomach tissue.

We established a mouse monoclonal antibody (Mab) KM93 which recognized sialyl Le(x)-carbohydrate epitope determined by solid phase radioimmunoassay using a panel of authentic glycolipids. The specificity of KM93 was similar to another anti-sialyl Le(x) Mab CSLEX-1 established previously, and different from that of Mab FH6 which recognized sialyl Le(x)-i (sialyl dimeric Le(x)). In a further study, however, we found that KM93 reacted with some glycolipids much more strongly than CSLEX-1 did on thin-layer chromatography (TLC) plates. We purified two gangliosides named K-1 and K-2 from gastric cancer cell line KATOIII, and three gangliosides named H-1, H-2, and H-3 from human stomach. KM93 reacted with all of these glycolipids. CSLEX-1 reacted with K-1 and K-2 with less intensity than KM93 did, and faintly reacted with H-1, but not at all with H-2 or H-3. FH6 did not react with K-1, K-2 or H-1, while it stained H-2 and H-3. In spite of this different reactivity with Mabs, analysis by proton nuclear magnetic resonance (1H NMR) proved that carbohydrate structure of K-1 and H-2 were the same: NeuAc alpha 2-->3Ga1 beta 1-->4 [Fuc alpha 1-->3] G1cNAc beta 1-->3 Ga1 beta 1-->4G1c beta 1-->1Cer. The H1 NMR spectrum of H-3 also indicated that H-3 consisted of the same sugars as K-1. These results indicated that KM93 had wider reactivity than CSLEX-1, and that the distinct reactivity of KM93 from CSLEX-1 was not caused by sugar moiety. It was also shown that the interaction of sialyl Le(x) sugar determinant with MAb depended on the tissue origin of molecules carrying carbohydrate.

Amino Acid Sequence↗

PubMedDate not supplied

Comparison of the closing dynamics of mechanical prosthetic heart valves.

To compare the closing dynamics of mechanical tilting disk prosthetic heart valves (OmniScience 25 [OS25], Medtronic-Hall 25 [MH25], Bjork-Shiley Monostrut 29 [BS29]) and bileaflet valves (CarboMedics 29 [CM29]) in the mitral position, an x-ray high speed video camera (XHVC) and a mechanical mock circulator were used. From the continuous images taken with the XHVC, the starting point of closing and the period during closing (PDC) were measured. Pressures and flow rate were recorded at 500 Hz synchronously with the XHVC. A pressure difference across the valves at the onset of closing (dpc) was newly introduced to compare the closing response. Using 60 and 100 bpm, the following results were obtained: 1) the CM29 had less PDC and maximum backflow rate than the BS29; 2) the dpc and the PDC at 100 bpm were larger than those at 60 bpm; 3) the dpc of the MH25 was the lowest; and 4) the PDC of the CM29 was the shortest. With regard to the effect of valve design on closing dynamics, it was shown that: 1) less momentum of inertia of the occluder and disk traveling angle resulted in lower dpc and shorter PDC, and 2) the higher the dpc and the PDC became, the larger the maximum backflow rate that was generated, and 3) low final closing speed will be achieved for small disk travelling angle.

Biomechanical Phenomena↗

PubMedDate not supplied

Management of the pancreatic metastases from renal cell carcinoma: report of four resected cases.

The pancreas is an uncommon site for metastasis from renal cell carcinoma. In most cases, pancreatic metastases occur as part of widespread nodal and visceral involvement, and there is thus evidence of metastatic disease elsewhere in the body. We present 4 cases with resectable pancreatic metastases arising from renal cell tumors without involvement of the regional lymph nodes at the operation. Three cases out of 4 were asymptomatic and the pancreatic metastases were detected by routine follow-up examination of renal cell carcinoma. Aggressive surgical treatment for the solitary metastatic lesion is advocated. Spread of renal cell carcinoma to the pancreas is, however, via the hematogenous route, and even solitary pancreatic metastasis may be one of the manifestations of the systemic metastasis of renal cell carcinoma. No pancreatic regional lymph nodes metastases were noted. Pancreatectomy should be undertaken to remove the tumor with adequate resection margins while preserving as much of the gland as possible. The prognosis of pancreatic metastases arising from a renal cell carcinoma is discussed with a review of the literature. Adjuvant chemo- and endocrine therapy should also be considered in these cases.

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