Search PubMed⌕ Search

Biomedical subjects

S Koike

Publications and source records attributed to S Koike.

At least 199 records · Page 11Linked to original sources

Fundamental tumor perfusion analysis with nuclear magnetic resonance imaging using gadolinium-diethylene triamine pentaacetic acid.

The measurement of blood perfusion is an important factor for both the diagnosis and follow-up of tumor lesions. However, noninvasive detection of this local blood flow factor is very difficult. To accomplish this, we tried to calculate tissue blood perfusion indexes with nuclear magnetic resonance imaging using gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA). We experimentally applied this method to C3H mouse's tumor NFSa (fibrosarcoma) and its recurrence tumor R1137, whose experimental hypoxic cell fraction is different; that is, R1137 is more oxic than NFSa. Imaging pulse sequence was T1 (TR = 1,000 ms, TI = 300 ms), and longitudinal relaxation rate (R1 = 1/T1) values were calculated. Injected dose of Gd-DTPA was 0.1 mmol/kg. The T1 images produced are from both the preinjection period from every 5 min postinjection for 30 min. Using two-exponential analysis and compartment analysis we calculated two fundamental parameters: uptake index and flow index as blood perfusion factors. We found that this method has the possibility of differentiating the tissue's hypoxic cell fraction and is effective both for follow-up study after radiation therapy and for tissue characterization.

Animals↗

The steroid binding domain of porcine estrogen receptor.

For the purpose of characterizing the estrogen binding domain of porcine estrogen receptor (ER), we have made use of affinity labeling of partially purified ER with [3H]tamoxifen aziridine. The labeling is very efficient and selective particularly after partial purification of ER. A 65,000-dalton (65-kDa) band was detected on the fluorogram of a sodium dodecyl sulfate-polyacrylamide gel, together with a 50-kDa band and a few more smaller bands. The 50-kDa protein appears to be a degradation product of the 65-kDa protein in view of the similar peptide map. ER was affinity labeled before or after controlled limited proteolysis with either trypsin, papain, or alpha-chymotrypsin. The labeling patterns of limited digests indicate that a fragment of about 30 kDa is relatively resistant to proteases and has a full and specific binding activity to estrogen, whereas smaller fragments have lost much of the binding activity. This fragment is very hydrophobic and probably corresponds to the carboxy half of ER.

Animals↗

Molecular cloning and characterization of rat estrogen receptor cDNA.

A cDNA clone of rat uterus estrogen receptor (ER) has been isolated and sequenced. This clone contains a complete open reading frame encoding 600 amino acid residues which is 5 and 11 amino acids larger than the corresponding molecules of human and chicken, respectively. The molecular weight of this protein is calculated to be 67,029. When this clone was ligated to the pSV2 vector and transfected into COS7 cells, a protein was produced that had the same affinity to estrogen as rat uterus ER. This sequence shows 88% homology with human ER; 528 amino acids are identical and 14 amino acids are conservative substitutions. The comparison of rat, human and chicken ER sequences indicate the presence of three highly conserved regions suggesting that these regions play important roles in ER function. The putative DNA-binding domain is completely identical in rat, human and chicken. The C-terminal half region which is thought to be the estrogen binding domain is also highly conserved and is rich in hydrophobic amino acid residues. Southern blot analysis of genomic DNA with ER cDNA as a probe has shown that related sequences are present in the genome.

Amino Acid Sequence↗

The presence of an aberrant type of human chorionic gonadotropin in patients with gastric or colorectal cancer.

Beta subunits of human chorionic gonadotropin (beta-hCG) and human chorionic gonadotropin-like substance (hCGLS) were measured radioimmunologically in the serum and malignant tissue from patients with gastrointestinal cancer. Since serum beta-hCG and hCGLS correlate closely to those in cancer tissues, it is assumed that these two gonadotropins originate from cancer tissues. The serum hCGLS levels in 54 patients with gastrointestinal cancer were significantly higher, when compared with the findings in 19 healthy volunteers and 10 peptic ulcer patients. The frequency of high levels of serum hCGLS accounted for 71 per cent of those with operable gastric cancer, 44 per cent of those with inoperable gastric cancer, 100 per cent of those with operable colorectal cancer, and 67 per cent of those with inoperable colorectal cancer. On the contrary, serum beta-hCG levels did not differ between the volunteers and the cancer patients. In the 17 sera and 15 cancer tissues assayed, beta-hCG did not correlate to hCGLS. Moreover, the high levels of beta-hCG in cancer patients occurred in only 1/14 (7.1 per cent) of the assayed serum, and in 5/14 (35.7 per cent) of the cancer tissue. The increased production of these two hCGs may result from neoplastic transformation of an unrestrained fetal genome responsible for hCG production during gestation. It is assumed that the increased producibility of a defective hCG, i.e., an aberrant hCG such as hCGLS, is characteristic of malignant tumors.

Chorionic Gonadotropin↗

Enhanced antitumor efficacy with a combination of hyperthermochemotherapy and thermosensitization with polyamine antimetabolites in nude mice.

In an attempt to enhance the antitumor effects of hyperthermochemotherapy, methylglyoxal-bis-guanylhydrazone (MGBG) and alpha-difluoromethylornithine (DFMO) were used in combination with hyperthermochemotherapy of 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)-3-nitrosoure a (ACNU) against human gastric cancer (ST-2) xenotransplanted into nude mice. After priming with DFMO and MGBG, ACNU was given ip and subsequently, a 23 minute-hyperthermia was carried out by placing the leg with the tumor into a water bath of a temperature of 43.5 +/- 0.1 degrees C. The second hyperthermic treatment was given in the same manner after 48 hours. MGBG and DFMO were administered for 4 successive days from the previous day of the first hyperthermia. In mice treated with DFMO plus MGBG, either tumor growth or tumor tripling time was much the same as in the control, while in mice given MGBG, DFMO plus heat, there was a diminution in tumor growth. Hyperthermia together with MGBG, DFMO plus ACNU brought about remarkable antiproliferative effects on ST-2 tumor growth, compared to three regimens with MGBG, DFMO plus heat, MGBG, DFMO plus ACNU, as well as ACNU plus heat. These data suggest that a combination of MGBG with DFMO leads to a favorable thermosensitization to the antitumor efficacy of ACNU.

Animals↗

Familial dilated cardiomyopathy and human leucocyte antigen. A report of two family cases.

Two familial cases of dilated cardiomyopathy were evaluated by HL-A typing. In the case of the first family, the mode of inheritance is likely to be an autosomal dominant trait. Only the affected individuals carried the identical HL-A haplotype (A2, Bw54, Cw1, DR4, DQw3), while the unaffected members do not share this pattern. In the second family case, the disease is probably inherited by autosomal recessive traits. All of the family members examined shared the identical HL-A haplotype (A24, Bw52, DR2, DQw1), but only the affected individuals were homozygous for this haplotype.

Adult↗

[A case of non-Hodgkin's lymphoma manifesting an eyelid tumor as a major symptom].

It is well known that a majority of non-Hodgkin's lymphoma (NHL) in the head and neck region arises from the Waldeyer's ring and neck lymph nodes. This report covers a rare case of a 69 year-old male with a symptom like the Mikulicz syndrome, who was diagnosed as having the NHL of B-cell type. This patient has been in complete remission following local radiotherapy for the tumor of the eyelid.

Aged↗

[Semi-quantitative evaluation of the intrapartum variable deceleration of the FHR pattern and its association with umbilical cord blood gas analysis].

Variable daceleration of FHR combined with no other abnormal pattern was semi-quantitatively evaluated to establish the diagnostic value of variable deceleration for fetal distress. FHR charts of 55 low risk vaginal deliveries by direct monitoring were analysed and the SDA (Sum of Dip Area) was calculated using the following equation: SDA = sigma Duration of dip (sec.) X Amplitude of dip (bpm.) X 10(-2) and correlation between SDA and umbilical cord blood gas analysis was obtained. A significant correlation was observed between SDA during labor (from 5 cm cervical dilation to delivery) and cord blood gas data. pHuv:r = -0.445 (p less than 0.005), PO2uv:r = -0.358 (p less than 0.01), BEuv:r = -0.538 (p less than 0.001), pHua:r = -0.441 (p less than 0.005), BEua:r = -0.463 (p less than 0.001). In 14 cases which showed prolonged deceleration (PD:more than 120 sec. in duration and below 100 bpm. in dip), excellent correlation was observed between the SDA of PD and pHuv:pHuv = 7.425-7.74 X 10(-4) SDA of PD (r = -0.756, p less than 0.005), whereas in 21 cases with severe variable deceleration (SVD:more than 60 sec. and recovered within 120 sec. in duration or below 60 bpm. in dip) no significant correlation was seen between the SDA of SVD and pHuv. These results suggest that the SDA value is helpful in evaluating variable deceleration during labor.

Female↗