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Biomedical subjects

M Kitano

Publications and source records attributed to M Kitano.

At least 145 records · Page 8Linked to original sources

A standardized method of using nude mice for the in vivo screening of antitumor drugs for human tumors.

Human tumors transplanted into nude mice have long been used to assess the effectiveness of antitumor drugs and yet there is still no established standard method in preclinical practice for screening new antitumor drugs in vivo using nude mice. Thus, a cooperative study on the feasibility of a human tumor/nude mouse system for the in vivo screening of drugs was conducted by the Japanese Research Society for Chemosensitivity of Cancer. Two human stomach cancers, H-111 and SC-6-JCK, and one human colon cancer, Co-4, were transplanted serially into nude mice and used as gastrointestinal tract tumors with stable tumor growth. The appropriate dosage of six well-known antitumor drugs [mitomycin C (MMC), cyclophosphamide (CPA), nimustine hydrochloride 1-(4-amino-2-methyl-5-pyrimidinyl) methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU), cis-platinum (II) diaminodichloride (CDDP), adriamycin (ADM) and 5-fluorouracil (5-FU)] in human tumor-bearing nude mice was determined based on the maximum tolerance dose of the drug. The respective dosages were 6 mg/kg of MMC x 1 (i.p.), 120 mg/kg of CPA x 1 (i.p.), 30 mg/kg of ACNU x 1 (i.p.), 8 mg/kg of CDDP x 1 (i.p.), 8 mg/kg of ADM x 1 (i.v.), and 50 mg/kg of 5-FU q4d x 3 (i.p.). Three weeks after treatment, drug effectiveness was judged by the tumor growth inhibition rate. Treatment with these appropriate doses appeared to show the maximum effect of the respective drugs on the tumor-bearing nude mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Functional integrity of hepatocyte canalicular membrane transport of taurocholate and bilirubin diglucuronide in Eisai hyperbilirubinuria rats.

Eisai hyperbilirubinuria rats (EHBR) are characterized by conjugated hyperbilirubinemia, and impaired or defective excretion of bilirubin, reduced glutathione and other organic anions from hepatocytes. Hepatocyte canalicular membrane vesicles (CMV) from EHBR and normal SD rats were studied with regard to taurocholate (TC) transport driven by ATP or a membrane potential and bicarbonate-stimulated bilirubin diglucuronide (BDG) transport. ATP-dependent uptake or association of BDG with CMV was also studied in both strains of rats. No significant differences in the uptake of TC and BDG by CMV were observed. This indicates the functional integrity of the canalicular transporters for both organic anions in EHBR. Biliary excretion of taurolithocholic acid sulfate (TLCS) is defective in EHBR. However, TLCS inhibited ATP-dependent TC uptake by SD rat CMV competitively, which may be against the hypothesis that a common organic anion carrier is defective in canalicular membranes of jaundiced rats.

Animals↗

Suppression of plasma endothelin-1 level by alpha-human atrial natriuretic peptide and angiotensin converting enzyme inhibition in normal men.

The effect of synthetic alpha-human atrial natriuretic peptide (alpha-hANP) on plasma endothelin-1 (ET-1) level was examined in 6 healthy subjects. Intravenous infusion of alpha-ANP (0.1 micrograms/kg/min) resulted in significant falls in plasma renin activity and aldosterone, but without effect on ET-1 level. An angiotensin converting enzyme inhibitor, captopril, increased plasma renin activity and decreased aldosterone, respectively. However, plasma ET-1 levels were not modified by captopril. In cases with alpha-hANP infusion after captopril (25 mg, p.o.,), the renin-angiotensin-aldosterone system was further inhibited compared with the first group, and ET-1 at 60 min was significantly suppressed from the baseline. These data suggest that alpha-hANP when combined with captopril brings about the suppression of plasma ET-1 concentrations in men.

Adult↗

Gingival leiomyomatous hamartoma: immunohistochemical and ultrastructural observations.

A rare case of leiomyomatous hamartoma of the gingiva is reported and the immunohistochemical and ultrastructural features described. A polypoid mass which presented with the appearance of a congenital epulis was located in the midline of the maxillary alveolar ridge of a two-year-old boy. Histologically, the mass was without a capsule and was composed mainly of irregularly arranged fasciculi of large spindle cells resembling smooth muscle cells. The immunohistochemical staining for desmin was strongly positive in these cells. Many nerve fibers were intermingled with them. Ultrastructurally, the cytoplasm was filled with thin filaments associated with dense patches. Numerous pinocytotic vesicles were present on the cytoplasmic membrane. These findings indicated that the mass consisted mainly of mature smooth muscle cells. The clinical and histological features suggest that the smooth muscle cells in the lesion are of hamartomatous or choristomatous origin, in contrast to true leiomyoma or granular cell congenital epulis.

Cell Nucleus↗

[Clinical application of the thoracic balloon for postpneumonectomy patients].

Pneumonectomy may result in complications such as continuous intrathoracic bleeding and mediastinal shift. We used a thoracic balloon made of silicone rubber in 15 postpneumonectomy patients in an attempt to prevent such complications. Two types of thoracic balloons were used in our series. Type 1 thoracic balloon is a simple balloon requiring cooperation with a drainage tube, and Type 2 is a combination balloon and drainage tube. During surgery, air was injected into the thoracic balloon through an air filter. After removal of the thoracic balloon, infusion of sulfur hexafluoride, SF 6, into the thoracic cavity was performed on the 7th to 10th postoperative days. Placement of thoracic balloons in the pleural space after pneumonectomy is a simple, safe and useful method of preventing both intrathoracic bleeding and mediastinal shift.

Aged↗

[Postoperative lung function in patients with funnel chest].

We evaluated the postoperative lung function determined by spirometry in 54 patients with funnel chest (48 males and 6 females: age range, 4-18 years). Thirty-one patients had sternal turnover as corrective surgery, while 23 had sternal elevation with absorbable PLA (polylactic acid) strut. The mean value of vital capacity as a percentage of predicted (%VC) was 97.3% before operation. %VC was decreased at 3 months (80.5%), 6 months (87.4%), 12 months (82.8%), 24 months (85.9%), and 36 months (77.7%) after the operation (p < 0.01). In patients who had sternal elevation, %VC was decreased at 3 months but not at 6 months, 12 months, 24 months, or 36 months after the operation, while %VC was decreased at any point after the operation in patients who had sternal turnover. No significant changes were seen in forced expiratory volume in one second as a percentage of predicted (FEV1.0%), nor in the ratio of residual volume to total lung capacity (RV/TLC). In conclusion, sternal elevation with PLA strut is a better corrective surgery for funnel chest than sternal turnover, because of its less lung function loss after the operation.

Adolescent↗

Plasma levels of superoxide dismutase and its isomers in patients with chronic renal disease.

To evaluate the significance of Cu,Zn-superoxide dismutase (SOD) in chronic renal disease, we evaluated the plasma SOD activity and analyzed the plasma Cu,Zn-SOD isomers employing gel column chromatography. The plasma SOD activity was determined as the biological activity using the nitrite method and the Cu,Zn-SOD concentration was assayed from the immunological activity using enzyme-linked immunosorbent assay (ELISA). The subjects comprised 185 patients with chronic glomerular disease and 20 hemodialysis patients. Plasma from 170 healthy persons was employed as a control. Both the plasma biological activity and plasma level of Cu,Zn-SOD determined by ELISA were elevated in patients with chronic glomerular disease. In hemodialysis patients, a marked increase in Cu,Zn-SOD level (ELISA) was noted in comparison with the increase in SOD biological activities. Gel column chromatography demonstrated a marked increase in Cu,Zn-SOD monomer which was enzymatically inactive. From these results, we conclude that a marked elevation of the plasma level of Cu,Zn-SOD in hemodialysis patients was caused by an increase in the enzymatically inactive Cu,Zn-SOD monomer.

Adult↗

[Hemodynamic changes in acute pancreatitis].

Hemodynamics studies were carried out from days 1-5 following the onset of illness in 7 patients with severe pancreatitis (group A) and in 7 patients with moderate pancreatitis (group B). Patients in both groups had a higher cardiac index (CI) and a lower systemic vascular resistance (SVR) than normal patients during 5 days of illness, and patients in group A had a higher CI of 5.38 +/- 0.841 x min/m2 and lower SVR of 889 +/- 234dyn.sec/cm5 than those in group B on day 4. Patients in group A had a lower pulmonary vascular resistance than normal patients on days 1, 3, and 4, but those in group B did not show this hemodynamic change. Group A patients had a higher pulmonary wedge pressure of 11.9 +/- 8.4mmHg and depressed left ventricular stroke work index of 59.8 +/- 17.8g.m/m2 as compared with group B (5.6 +/- 3.4mmHg, 77.7 +/- 23.6g./m2, respectively). These findings indicate that a hyperdynamic hemodynamic state may exist in the early stages of moderate and severe pancreatitis and myocardial depression may be evident in severe pancreatitis.

Acute Disease↗

[Bullectomy utilizing EndoGIA under thoracoscopic guidance].

We report 5 cases of pneumothorax successfully treated with an endoscopic GIA stapling device (EndoGIA) under thoracoscopic guidance. There were no complications such as air leak or bleeding, and patients were discharged 2 to 7 days after operation. Surgical procedure utilizing EndoGIA has been proved to have advantages such as less pain, early return to normal activity and more cosmetic incision.

Adolescent↗

[Surgical treatment of metastatic lung tumors].

From January 1970 to March 1991, 72 operations in 55 patients (31 males and 24 females) with metastatic lung tumors were performed in our department. Their cumulative survival rates was 25.5% at five years. With analysis of the various prognostic factors, patients both with solitary metastases and without lymph node metastases had a good prognoses. However, even in patients with recurrent lung metastatic tumors, long time survival was achieved with reoperation in two patients. We concluded that reoperation with or without effective chemotherapies was effective in selected patients.

Adolescent↗

Studies on pyridonecarboxylic acids. 1. Synthesis and antibacterial evaluation of 7-substituted-6-halo-4-oxo-4H-[1,3]thiazeto[3,2-a]quinoline-3- carboxylic acids.

A series of [1,3]thiazeto[3,2-a]quinoline-3-carboxylic acids and their esters were prepared and evaluated for antibacterial activity. The derivatives with a hydrogen or methyl group at C-1, fluorine at C-6, and piperazinyl or 4-methyl-1-piperazinyl group at C-7 showed superior in vitro antibacterial activity, and the derivatives with 4-methyl-1-piperazinyl group at C-7 had potent in vivo activity. Compound 29a (NM394) showed excellent in vitro antibacterial activity and low toxicity but poor absorption from the gastrointestinal tract. Compound 29ee (NM441), an N-[(5-methyl-2-oxo-1,3-dioxol-4-yl)methyl] derivative of 29a, was found to possess a favorable pharmacokinetic profile and oral activity superior to that of ciprofloxacin in experimental animals.

Administration, Oral↗

Meningioma of the mandible.

This is the first case report to the authors' knowledge of a primary extracranial meningioma located in the mandible. Ultrastructurally, the tumor cells had intricate cellular membranes and desmosome-like attachment structures. Using immunohistochemical analysis, the tumor expressed both epithelial membrane antigen and vimentin. Although the origin of extracranial meningiomas has been attributed to proliferation of ectopic embryonal nests of arachnoidal cells, the proliferation of perineural cells of peripheral nerves also is possible as a result of the structural and functional similarities of perineural cell and arachnoid cells. The authors suggest that extracranial meningiomas may be more common than published reports indicate because of certain histologic similarities between these tumors, neurilemomas, and solitary neurofibromas.

Biomarkers↗

Paraganglioma of the posterior mediastinum: value of magnetic resonance imaging.

A case of paraganglioma arising in the posterior mediastinum in a 29-year-old man diagnosed by magnetic resonance imaging is reported. Excision of mediastinal paraganglioma is often hazardous because of its rich vascular supply and tendency to involve surrounding structures. Magnetic resonance imaging is valuable for the preoperative diagnosis of this vascular tumor as well as for determination of its resectability and appropriate surgical procedure.

Adult↗

Juvenile angiofibroma of the maxillary sinus. A case report.

The clinicopathological features of a rare case of juvenile angiofibroma originating from the maxillary sinus of a 13-year-old boy are reported. This tumor was composed of angiomatous and fibrous structures. The analysis of nucleolar organizer regions (NOR) of the various components of this tumor indicated that the fundamental elements were the fibroblastic cells, rather than the vascular endothelial cells.

Adolescent↗

Strain difference of susceptibility to 4-nitroquinoline 1-oxide-induced tongue carcinoma in rats.

Strain difference of susceptibility to 4-nitroquinoline 1-oxide (4NQO)-induced squamous cell carcinomas of the tongue among Dark-Agouti, Long-Evans, Sprague-Dawley, ACI/Ms, Fischer 344, Donryu and Wistar/Furth rats was surveyed by evaluating the survival times, incidences and sizes of developed tumors as markers of susceptibility. Administration of 4NQO dissolved in drinking water induced squamous cell carcinomas in various sites of the upper digestive tract mucosa of all the experimental male and female rats of the seven strains. Regarding the mean survival times, Wistar/Furth rats survived much longer than any other strain of rats, and Dark-Agouti showed the shortest survival. The incidence of large, mass-type carcinomas of the tongue of Dark-Agouti rats was higher than in any other strain of rats, while that of Wistar/Furth rats was the lowest. Subsequently the mitotic activity and bromodeoxyuridine incorporation in the tongue epithelium of Dark-Agouti and Wistar/Furth rats were estimated after a short-term administration of 4NQO. There was a pronounced difference between the two strains of rats, because the proliferative responses of the tongue epithelium of Dark-Agouti rats to the 4NQO stimulation were much higher than those of Wistar/Furth rats. These results indicated that there are marked differences in the susceptibility to 4NQO-induced tongue carcinoma among the seven strains of rats, and that Dark-Agouti and Wistar/Furth rats could be useful as models of highly and poorly susceptible strains, respectively, for further genetic analysis.

4-Nitroquinoline-1-oxide↗