Biomedical subjects

Y Arisawa

Publications and source records attributed to Y Arisawa.

At least 19 recordsLinked to original sources

PubMed2000

[Surgery using master-slave manipulators and telementoring].

Master-slave manipulators enhance surgeons' dexterity and improve the precision of surgical techniques by filtering out surgeons' tremors and scaling the movements of surgical instruments. Among clinically available master-slave manipulators, the epoch-making system called "da Vinci" developed by Intuitive Surgical Inc. (Mountain View, CA, USA), equipped with 2 articulated joints at the tip of the surgical instruments allowing 7 degrees of freedom, mimics the movements of surgeons' wrists and fingers in the abdominal or thoracic cavity. Today advanced telecommunications technology provides us excellent motion images using only 3-ISDN telephone lines. Experienced surgeons at primary surgical sites have been able to perform complex procedures successfully by consulting specialists at remote sites. Because telecommunications costs have become lower each year, telementoring will be come a routine surgical practice in the near future. The usefulness of surgical telementoring has been greatly enhanced by the development of a technique to illustrate on video images from two directions. Moreover, remote advisory surgeons will be able to provide the optimal operative field to operating surgeons using robotic camera holders with voice-recognition systems. In the near future, when master-slave manipulators will also be coupled with telementoring systems, remote experts could actually perform complex surgical procedures.

Humans↗

PubMed2000

Scarless endoscopic thyroidectomy: breast approach for better cosmesis.

An original technique for performing endoscopic thyroidectomy using a breast approach to avoid an operative scar in the neck was developed. The subcutaneous space in the breast area and the subplatysmal space in the neck were bluntly dissected through a 15-mm incision between the nipples, and CO2 was insufflated at 6 mm Hg to create the operative space. Three trocars were inserted at the breast, and dissection of the thyroid and division of the thyroid vessels and parenchyma were performed endoscopically using an ultrasonically activated scalpel. Four hemithyroidectomies and one partial resection of the thyroid for five female patients with thyroid adenomas 5 to 7 cm in diameter were successfully performed using this procedure. There were no conversions to open surgery or complications. No scars were apparent in the neck, and all patients were fully satisfied with the cosmetic results. Endoscopic thyroidectomy using a breast approach and low-pressure subcutaneous CO2 insufflation is a feasible and safe procedure, which results in satisfactory cosmetic results.

Adenoma↗

PubMed1998

Production of donor-derived offspring by transfer of primordial germ cells in Japanese quail.

We transfused concentrated primordial germ cells (PGCs) of the black strain (D: homozygous for the autosomal incomplete dominant gene, D) of quail into the embryos of the wild-type plumage strain (WP: d+/d+) of quail. The recipient quail were raised until sexual maturity and a progeny test of the putative germline chimeras was performed to examine the donor gamete-derived offspring (D/d+). Thirty-one percent (36/115) of the transfused quail hatched and 21 (13 females and 8 males) of them reached maturity. Five females and 2 males were germline chimeras producing donor gamete-derived offspring. Transmission rates of the donor derived gametes in the chimeric females and males were 1.8-8.3% and 2.6-63.0%, respectively. Germline chimeric and the other putative chimeric males were also test-mated with females from the sex-linked imperfect albino strain (AL: d+/d+, al/W, where al indicates the sex-linked imperfect albino gene on the Z chromosome, and W indicates the W chromosome) for autosexing of W-bearing spermatozoa: No albino offspring were born.

Animals↗

PubMed1997

[A case of inoperable advanced gastric cancer remarkably responding to combined chemotherapy with UFT-E, MMC and PSK].

A 55-year-old male consulted a local doctor with the complaint of epigastralgia. Examination of the upper gastrointestinal tract revealed gastric cancer (Borrmann Type II) and he was referred to our hospital for operation. A few lymph nodes were palpable in the left supraclavicular fossa, and the biopsy of those lymph nodes revealed metastatic adenocarcinoma. The CT scan of the abdomen showed enlargement of paraaortic lymph nodes. Then, the patient was determined inoperable (T3, N4, H02 P01, M1 stage IVb). He was treated as an outpatient with UFT-E (300 mg/day, orally), Krestin (PSK 3.0 g/day, orally) and Mitomycin C (MMC 6 or 8 mg once a week, intravenously repeated interval of 4 weeks). The total dose of UFT-E, PSK and MMC was 219 g, 1,095 g and 136 mg, respectively. One month later, lymph nodes in the supraclavicular fossa disappeared, and the lesion in the stomach completely responded. We have followed the patient for more than one year. He visits our the outpatient department and has kept working until now.

Adenocarcinoma↗

PubMed1996

Regional chemotherapy for colorectal hepatic metastases: evidence for improved survival with new drug combinations.

BACKGROUND: In patients with colorectal hepatic metastases, response rates with hepatic arterial infusion (HAI) FUdR (5-Fluoro-2-deoxyuridine) are significantly higher than with systemic fluoropyrimidines. We report a novel animal model of intrahepatic therapy for hepatic metastasis for the study of methods to increase response rates and improve survival. METHODS. BD-IX rats are injected intrasplenically with K12/TRb cells. When hepatic metastases are established, animals are treated with hepatic or systemic chemotherapy, and the response to treatment, survival, and cause of death is determined. RESULTS: Significant responses were observed with low- and high-dose HAI FUdR (p = 0.03 and 0.001, respectively). Only high-dose FUdR controlled hepatic disease. HAI FUdR alone did not prolong survival compared with control, but combination systemic FUdR and HAI FUdR did (p = 0.04). Continuous HAI of either 5-fluorouridine or mitomycin C has not previously been reported. There was no significant difference in response to FUdR, 5-fluorouridine, or mitomycin C. However, combination HA bolus mitomycin C plus either HAI 5-fluorouridine or HAI mitomycin C showed synergy with improved survival compared with all treatment groups (p < 0.0001). CONCLUSIONS: The combination of bolus hepatic artery mitomycin C with either HAI mitomycin C or HAI 5-fluorouridine yields significant response rates, and survival is improved by this novel combination therapy.

Animals↗

PubMed1996

[Adjuvant chemotherapy with cyclophosphamide, adriamycin, and CDDP (CAP) for high risk endometrial cancer after complete surgery].

One hundred and six patients with endometrial cancer were treated at Tsukuba University Hospital between 1983 and 1992. Sixteen patients who underwent complete resection were at high risk for recurrence and were given adjuvant platinum-based, multiagent chemotherapy instead of adjuvant radiotherapy. Eligibility criteria included outer-third myometrial invasion (group 1; n = 5), pelvic lymph node metastasis (group 2; n = 3) or both myometrial invasion and lymph node metastasis (group 3; n = 8). Of these three groups at high risk for recurrence, each patient in groups 1 and 2 developed recurrence and died. In group 3 two patients developed recurrence and one patient has died. There was one treatment death due to neutropenic sepsis in group 3. The recurrence sites in all four patients were local and no distant recurrence was noted. In other words, of 15 patients (excluding one treatment death) at high risk for recurrence, three of 12 patients (25%) with deep myometrial invasion and three of 10 patients (30%) with positive pelvic lymph nodes developed recurrence and died. The other 12 patients (include one patient with recurrence; 100 months) have survived for a long interval (range, 45-131 months). The survival rates for stage I, II, III, and IV are 92.6, 89.5, 60.0%, respectively. Patients with stage I in this study had a better survival than those with stage I in the 1984 annual report of the Japan Society of Obstetrics and Gynecology (p < 0.05). The findings of this prospective clinical trial supported those of the randomized trial comparing adjuvant CAP with radiation therapy.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1995

Hepatic artery dexamethasone infusion inhibits colorectal hepatic metastases: a regional antiangiogenic therapy.

BACKGROUND: A randomized trial treating colorectal hepatic metastases demonstrated that hepatic arterial floxuridine (FUdR) with dexamethasone increased tumor response compared with hepatic arterial FUdR alone (Cancer 1992;69:327-34). The mechanism of this improvement is unclear. METHODS: We investigated the effect of hepatic arterial dexamethasone with or without FUdR on the growth of colorectal hepatic metastases in an animal model. BD-IX rats were inoculated intrasplenically with 10(7) K12/TRb colon cancer cells on day 0. On day 14, the hepatic metastases were counted and hepatic arterial catheters placed for chemotherapy. Forty-eight animals were randomized to 4 groups for 14 days of infusion with heparinized saline alone (group A), heparinized saline with dexamethasone 0.03 mg/kg/d (group B), heparinized saline with FUdR 2 mg/kg/d (group C), or heparinized saline with dexamethasone 0.03 mg/kg/d plus FUdR 2 mg/kg/d (group D). The hepatic metastases were recounted by laparotomy on day 28. Response in each rat was expressed in terms of percentage change in number of hepatic nodules between the number of hepatic nodules seen on days 14 and 28. In vitro chemosensitivity of K12/TRb to dexamethasone with or without FUdR was examined using an MTT (3-(4,5-dimethylthiazole-2-yl-2,5-diphenyltetrazolium bromide; Sigma, St. Louis, MO, U.S.A.) assay. The effect of dexamethasone on tumor-induced angiogenesis was tested using an in vivo assay. RESULTS: The mean percentage change in tumor nodules was +129% in group A, +17% in group B, -4% in group C, and -29% in group D (p = 0.002 A vs. B, p = 0.04 C vs. D). The MTT assay showed that dexamethasone had no direct effect on K12/TRb growth or on tumor FUdR sensitivity. Dexamethasone inhibited K12/TRb-induced angiogenesis in vivo. CONCLUSIONS: Hepatic arterial dexamethasone is effective in treating colorectal hepatic metastases and is more effective when combined with hepatic arterial FUdR. The antiangiogenic activity of dexamethasone may partially contribute to its efficacy.

Adenocarcinoma↗

PubMed1995

[Analysis of familial aggregation of ovarian and breast cancer in patients with ovarian cancer].

In 118 patients with common epithelial ovarian tumors (carcinomas and tumors of borderline malignancy) treated at Tsukuba University Hospital and Tsukuba-Gakuen Hospital, family histories of ovarian and breast cancer were obtained from medical records or in interviews, and familial aggregation of these cancers was examined. 1. A positive family history was found in 10 patients (8.5%). The high incidences of familial ovarian cancer and ovarian cancer in patients who were previously affected with breast cancer were statistically significant. 2. Patients with serous adenocarcinoma showed a significantly greater rate of positive family history than those with mucinous adenocarcinoma. 3. No significant correlation was seen between the clinical stage and a positive family history. 4. Every patient except one with a positive family history had onset of ovarian cancer after menopause. The age at onset for familial ovarian cancer cases was younger than that for the patients' relatives who were affected previously. 5. There were 14 healthy women considered to be at high risk for ovarian cancer among 5 familial ovarian and 2 familial ovarian and breast cancer aggregations. These preliminary findings suggest that screening for early ovarian cancer should be conducted in high risk relatives of familial cancer patients and women affected with breast cancer previously. More detailed studies are needed to define the occurrence of familial or hereditary ovarian and breast cancers in Japan.

Adenocarcinoma, Mucinous↗

PubMed1995

[An immunohistological study on expression of glutathione S-transferase pi (form) in human ovarian carcinoma].

Specimens from 102 cases of ovarian cancer were stained immunohistochemically with a rabbit polyclonal antibody prepared against the placental form of the enzyme glutathione S-transferase (GST-pi). All 28 cases of mucinous adenocarcinoma, 19 of clear cell carcinoma and 4 of malignant transformed dermoid cysts were stained positively with the GST-pi antibody. These tumors are considered to be resistant to chemotherapeutic agents as compared with other epithelial tumors. With regard to the histological grade, the degree of staining was reduced according to the loss of differentiation. An investigation of the relationship between GST-pi stain and the prognosis of the 50 patients with stage 2,3 or 4, according to the Kaplan-Meier method, revealed that the prognosis improved as the staining decreased. In conclusion, results suggested that immunohistochemical staining of GST-pi is correlated with the chemoresistance of the tumor, and may predict the outcome in patients with ovarian cancer.

Adenocarcinoma, Clear Cell↗

PubMed1994

Short-term intrahepatic FUdR infusion combined with bolus mitomycin C: reduced risk for developing drug resistance.

This study evaluates tumor response, survival, and development of resistance to HAI chemotherapy, comparing a combination of bolus MMC and short duration FUdR to short duration FUdR alone or to long duration FUdR alone, using a rat hepatic metastases model. After intrasplenic injection of 10(7) K12/TRb colon cancer cells in BD-IX rats on day 0, hepatic metastases were evaluated and HA catheters were placed on day 14. The response was determined on day 28. Chemosensitivity of the hepatic metastases after HAI treatments was determined using the MTT assay. Bolus MMC with short duration FUdR as well as long-term FUdR alone provided better hepatic tumor response and survival than short-term FUdR alone. However, bolus MMC with short duration FUdR decreased the acquired resistance to FUdR, compared to long-term FUdR, without causing resistance to MMC. These results provide a rationale for using short duration of FUdR in combination with other drugs.

Animals↗

PubMed1994

[Treatment of stage Ia ovarian cancer].

Ninety-six patients with primary ovarian cancer were treated at Tsukuba University Hospital between 1984 and 1992. For all of these patients except stage IV, surgical treatment including pelvic and paraaortic lymphadenectomy was employed to confirm the clinical stage exactly. Re-staging laparotomy was performed in cases with an incomplete initial operation. In thirty cases the primary tumors were truly confined to the unilateral ovary (stage Ia). In six patients, though the tumor appeared to be confined to the unilateral ovary macroscopically at the time of the operation, the stage changed to Ic in one case, IIa in one case and IIIc in 4 cases as found by postoperative confirmation. The most common tumor in stage Ia was mucinous cystadenocarcinoma. In 23 patients with stage Ia, histological grading could be obtained. Twenty-one cases were low potential malignancy or grade 1, whereas grade 3 was found in only one case. None, except one case diagnosed as stage Ia, has had a recurrence in spite of the absence of adjunct therapy, but one patient with grade 3 endometrioid carcinoma died of the disease 10 months after staging laparotomy. In conclusion, even though the tumor appears to be confined to one ovary, a staging laparotomy should be conducted in all patients. When the tumor is proved to be limited to only one ovary and is also histologically confirmed to be less than grade 3, it is considered that no further treatment is necessary.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1993

Carbohydrate antigens and liver metastasis in colorectal cancer.

A comparative immunohistochemical study was performed to analyse the expression of cancer-associated carbohydrate antigens by primary and metastatic lesions of colon cancer. We used monoclonal antibodies which reacted with Lea, Lex and Tn as well as their sialylated derivatives. Twenty-one primary lesions in patients without metastasis and 26 primary and metastatic lesions in patients with liver metastasis were studied. Sialyl Lea was expressed by 57% of the primary lesions of patients without metastasis, 65% of the primary lesions of patients with metastasis and 73% of their liver metastases. Sialyl Lex was expressed by 60% of the primary lesions of patients with and without metastasis as well as by approximately 80% of the liver metastases. Sialyl Lea and sialyl Lex showed strong expressions in the liver metastases, significantly greater than in the primary lesions. The findings indicate the increased expressions of sialyl Lea and sialyl Lex to be correlated with liver metastasis of colorectal cancer.

Adenocarcinoma↗

PubMed1992

[Studies on the efficacy and safety of panipenem/betamipron in infections in surgical domain and the safety when mixed with lactate containing infusion].

Studies were done on the effectiveness and safety of panipenem/betamipron, a new carbapenem antibiotic, in infections in the surgical domain and its safety when dissolved in infusions containing lactate. The obtained results are summarized as follows. The preparation, 0.5 g/0.5 g or 1.0 g/1.0 g, was administered by intravenous drip infusion 2 to 3 times a day to 31 cases of patients with infections in the surgical domain. A physiological saline solution was used as the solvent in 21 cases (group A) of them and Solita T3, an infusion containing lactate, was used as the solvent in the 10 remaining cases (group B). As for its clinical effects, results were rated as "excellent" in 20, "good" in 7, "fair" in 3 and "no response" in 1 out of the 31 cases, and the efficacy rate was 87.1%. Regarding its bacteriological effects, results were rated as "disappeared" in 22, "decreased" in 2, "unchanged" in 1 and "unknown" in 1 out of 26 cases from which bacteria were isolated, hence the bacteria-clearance rate was 88.0%. As for side effects, skin rash was seen in 1 case and slight increases of GOT and GPT were noted as abnormal changes in laboratory data in 2 cases. These side effects were all observed among the cases in group A but not at all in group B where a lactate containing infusion was used as the solvent.

Adolescent↗

PubMed1991

Antitumor activity of fluoropyrimidines and thymidylate synthetase inhibition.

Experimental chemotherapy with 5-fluorouracil (5-FU; 60 mg/kg), 1-hexylcarbamoyl-5-fluorouracil (HCFU; 70 mg/kg), 3-(3-(6-benzoyloxy-3-cyano-2-pyridyloxycarbonyl)benzoyl)-1-ethoxym ethyl-5- fluorouracil (BOF-A2; 30 mg/kg) and UFT (20 mg/kg as tegafur with uracil at a molar ratio of 1:4) was performed using human gastric (H-111) and colon (Co-4) carcinoma strains in nude mice. 5-FU was administered ip with a q4d x 3 schedule and the other agents were given po daily for three weeks. Concentrations of 5-FU in the serum and the tumor were assessed by gas chromatography-mass fragmentography, two hours or 12 days (5-FU) after the last treatment, and thymidylate synthetase (TS) was assayed according to the method of Spears et al. using the same schedule. The antitumor activity of the agents was assessed in terms of the actual tumor weight at the end of the experiment. HCFU was effective against both strains and 5-FU was effective against Co-4, although the other agents were ineffective against either strain. Statistically significant correlations were found between the serum and tumor concentrations of 5-FU and antitumor activity. Statistically significant correlations were also observed between the antitumor activity and TS inhibition rate (TSIR) and the activity of free thymidylate synthetase (TSfree), with higher TSIR and lower TSfree resulting in higher antitumor activity. Therefore, TSIR and TSfree were thought to be promising indicators for predicting the antitumor activity of fluoropyrimidines.

Adenocarcinoma↗

PubMed1990

Nude mouse resists hepatic metastasis of the allogeneic tumor, colon-26.

The ability of the host-immune defense mechanism of nude mice and their immunocompetent littermates to prevent liver metastases from the murine colon carcinoma, colon-26, was assessed. Give thousand tumor cells suspended in 0.05 ml of Hank's balanced salt solution were inoculated into the spleens of BALB/c nu/+ and BALB/c nu/nu mice. On the 21st day after inoculation, all the mice were sacrificed, and the liver metastases counted and the livers weighed. All the BALB/c nu/+ mice were found to have developed hepatic metastases with a mean of 10 nodules, whereas no hepatic metastases were observed in any of the 10 BALB/c nude mice. On the other hand, 4 of 6 nude mice developed hepatic metastases after treatment with anti-asialo GM1 antibody. These results indicate that the BALB/c nude mouse has an excellent host-immune defense mechanism for preventing liver metastasis, with NK cells in the liver and/or blood circulation perhaps playing an important role.

Animals↗

PubMed1990

[Enhancement of antitumor activity of mitomycin C against human breast carcinoma xenografts by pretreatment with KM 2210].

Three human breast carcinoma xenografts, MCF-7, R-27 and T-61 serially transplanted into nude mice were treated with mitomycin C (MMC) alone, KM2210 (estra-1, 3, 5(10)-triene-3, 17 beta-diol, 3 benzoate 17-[4-(4-bis(2-chloroethyl)amino)phenyl)-1-oxobutoxy)acetate) alone and KM2210 followed by MMC. One hundred or 300 mg of KM2210 per kg were administered orally daily from Day 1 to 4 and MMC at the dose of 3 mg/kg was given ip on Day 5. The antitumor activity of MMC on these xenografts was enhanced by pretreatment with KM2210, suggesting a new combination chemo- and endocrine therapy of hormone-dependent human breast carcinomas.

Animals↗

PubMed1989

Human breast carcinoma (ZR-75-1) serially transplanted into nude mice--with reference to estradiol dependency and sensitivity to tamoxifen.

Tumor cells of the ZR-75-1 line (1 X 10(7) in 0.5 ml) were inoculated into the right thigh muscles of BALB/c female nude mice which were, at the same time given 1.0 mg of estradiol subcutaneously. After the transferable strain had been established, the tumors were then transplanted into female and male nude mice either with or without estradiol treatment. Although no exponential tumor growth was observed in the untreated male and female nude mice, no complete rejection was found during the experiments. The estrogen receptor of this strain was positive and the growth of ZR-75-1 was dependent on exogenous estradiol. ZR-75-1 in the nude mouse was insensitive to tamoxifen treatment, given as 5 mg/kg intramuscularly twice a week, suggesting that dependency on estradiol is not necessarily correlated with endocrine sensitivity to tamoxifen.

Animals↗

PubMed1989

Antitumor activity of 7-N-(2-((2-(gamma-L-glutamylamino) ethyl) dithio) ethyl) mitomycin C (KW2149) against human tumor xenografts serially transplanted into nude mice.

The antitumor activity and toxicity of 7-N-(2-((2-(gamma-L-glutamylamino) ethyl) dithio) ethyl) mitomycin C (KW2149) were evaluated using a human tumor xenograft--nude mouse system, and compared with those of the maternal compound, mitomycin C. The maximum tolerated dose of KW2149 was estimated to be 15 mg/kg by bolus intraperitoneal or intravenous injection, at which a remarkable reduction of spleen weight was observed, suggesting bone marrow suppression by this agent. A bolus injection of KW2149 seemed to be more effective than a divided injection schedule, when a total of 15 mg KW2149/kg was administered to mice bearing breast (MX-1) and colon (Co-4) carcinomas. The antitumor activity of KW2149 was dose-dependent, and the difference in antitumor effect according to route of administration was minimal. The antitumor spectrum of KW2149 was essentially identical to that of mitomycin C administered intraperiotoneally as a bolus at a dose of 6 mg/kg.

Adenocarcinoma↗