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T Taguchi

Publications and source records attributed to T Taguchi.

At least 505 records · Page 28Linked 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↗

Enteric nervous system and endocrine cells demonstrated in the gut in teratomas.

A case of retroperitoneal teratoma, showing considerable morphological development presented as an encapsulated and pedunculated tumour with a seemingly mature intestinal loop. Markedly complex intramural nerve plexuses and numerous epithelial endocrine cells were revealed immunohistochemically in the gut tissue. Ten other mature teratomas containing gastrointestinal tissues were examined for comparison, but neither intramural ganglia nor nervous networks were found in the gut components, despite the presence of amine- and/or peptide-containing endocrine cells in all intestinal mucosa linings. Enteric endocrine cells were found to occur irrespective of the differentiation of intestinal layers or the occurrence of neural elements. These findings suggest that the epithelial endocrine cells of intestinal mucosa do not have the same origin as enteric neurons, but are rather of endodermal origin. This invertebrate well-formed teratoma, containing a highly organized enteric nervous system, suggests that teratoma and fetus in fetus are related entities distinguished by the presence of a vertebral axis.

Choristoma↗

Conversion of xanthine dehydrogenase to xanthine oxidase during ischemia of the rat small intestine and the effect of trifluoperazine on the conversion.

The conversion from xanthine dehydrogenase (XD) to xanthine oxidase (XO) and the effect of trifluoperazine (TFP), a calmodulin inhibitor, on the conversion were examined during the normothermic ischemia of the rat small intestine. Rat jejunums were stored in lactated Ringer's solution (LR) at 37 degrees C for various hours after intravascular flushing with LR. The extents of the conversion from XD to XO (%XO) constituted 21.1% +/- 3.0%, 36.2% +/- 7.0%, 63.2% +/- 8.1%, and 88.2% +/- 8.6% after 0, 2, 4, and 6 hours of the preservation, respectively (control group). The preservation without the intravascular flushing showed significant increase in the %XO (99.5% +/- 6.0%) only after 6 hours compared with those in the control group (P < .05). When the intestines were stored in LR containing 50 mg/L of TFP at 37 degrees C, or stored in LR at 37 degrees C after the intraperitoneal pretreatment with 10 mg/kg of TFP 1 hour before laparotomy showed significant decrease in the extents of the conversion after 4 hours (P < .005) and 6 hours (P < .025) of the preservation, compared with those in the control group. When the dose of TFP for the pretreatment was increased to 50 mg/kg, the suppressive effect on the conversion was found even after 2 hours (P < .025) as well as after 4 hours (P < .005) and 6 hours (P < .025) of the preservation. These results suggest that TFP could be effective on reducing the XO-mediated postischemic reperfusion injury by means of inhibiting the conversion during ischemia of the rat small intestine.

Animals↗

Characterization of 9q;15q whole-arm translocation derivatives in non-small cell lung carcinomas by fluorescence in situ hybridization.

We report derivative chromosomes, originally interpreted as 9q;15q whole-arm translocations, in tumor cells from two patients with non-small cell lung cancer (NSCLC). One of the tumors was diagnosed as an adenocarcinoma and the other as an adenosquamous carcinoma. In each case, there was no normal chromosome 9. Because of the pericentromeric location of the breakpoints, classical cytogenetic banding techniques did not permit determination of the centromeric origin of these derivative chromosomes. Fluorescence in situ hybridization (FISH) with satellite (alpha, beta, classical), ribosomal DNA, alpha-interferon (alpha-IFN), and whole chromosome painting probes indicated that the 9;15 rearrangement is dicentric in both tumors. In one of these cases, the derivative chromosome is interpreted as a dic(9;15) (p11;p11.2); the other case has a more complicated rearrangement involving reorientation of pericentromeric sequences. A 9q;15q whole-arm derivative chromosome was reported previously in another lung adenocarcinoma, suggesting that this abnormality may represent a recurrent change in lung carcinomas, particularly those displaying adenomatous features.

Aged↗

New markers, D16FC1 and Tp12, differentiate between rat chromosomes 16 and 17.

Problems in differentiating rat chromosomes 16 and 17 cytogenetically can be resolved with unique probes mapped to these chromosomes. Using somatic cell hybridization and nonisotopic in situ hybridization, probes D16FC1 and Tp12 were localized to 16p16-->p15 and 17q12.1-->q12.2, respectively. The locations of these probes can serve as reference points to facilitate mapping of future probes to rat chromosomes 16 and 17.

Animals↗

Chromosomal localization of the Ox-44 (CD53) leukocyte antigen gene in man and rodents.

The Ox-44 (CD53) leukocyte antigen contributes to the transduction of CD2-generated signals in T cells and natural killer (NK) cells and has been suggested to play a role in growth regulation. The gene encoding this protein was assigned to the midportion of mouse chromosome 3 by interspecific backcross mapping and to human chromosome region 1p21-->p13.3 and rat chromosome region 2q34-->q41 by fluorescence in situ hybridization. Comparative mapping data presented in this report demonstrate conservation of synteny within the region encompassing this gene in mouse (Cd53), human (CD53), and rat (CD53).

Animals↗

Phase II study of CPT-11, a new camptothecin derivative, in metastatic colorectal cancer. CPT-11 Gastrointestinal Cancer Study Group.

PURPOSE: A phase II study was conducted to evaluate the antitumor effect and toxicity of CPT-11 in patients with metastatic colorectal cancer. PATIENTS AND METHODS: From December 1989 to March 1991, 67 patients with metastatic colorectal cancer were enrolled in this study. Sixty-three patients were assessable for toxicity and response. Their median age was 57 years (range, 24 to 72). Forty-six patients (73%) had a good performance status of 0 or 1. Fifty-one patients (81%) had received prior chemotherapy. The major sites of metastasis were liver (63%) and lung (44%). CPT-11 was administered as a 100 mg/m2 weekly intravenous infusion, or as 150 mg/m2 every 2 weeks. The dose was reduced based on the grade of leukopenia and diarrhea, if necessary. RESULTS: A partial response was obtained in 17 of 63 assessable patients (27%; 95% confidence interval, 16% to 38%). The response rate in patients with prior radiotherapy or chemotherapy was 25% (13 of 52). Liver metastases showed a 15% (six of 40) response and lung metastases showed a 39% (11 of 28) response. The median duration of partial response was 127 days (range, 49 to 353) and the median overall duration of response was 208 days (range, 99 to 381). The major toxicities (> or = grade 3) were leukopenia (16%), diarrhea (13%), nausea and vomiting (13%), and alopecia (11%). Adverse effects were generally well tolerated and reversible. Treatment could be continued on an outpatient basis for patients without severe toxicity. Hemorrhagic cystitis was not encountered in this study. CONCLUSION: CPT-11 showed promising antitumor activity against metastatic colorectal cancer that was resistant to prior therapy. Further clinical trials of combination chemotherapy using CPT-11 are justified.

Adult↗

Dual-tracer autoradiography with thallium-201 and iodine-125 MIBG in BIO 14.6 cardiomyopathic Syrian hamsters.

Dual-tracer imaging of the heart with 125I-metaiodobenzylguanicline (MIBG) and 201Tl can simultaneously demonstrate the distribution of sympathetic nerve endings and the underlying myocardial perfusion. A quantitative dual-tracer autoradiographic study with 201Tl and 125I-MIBG was performed to investigate changes in the distribution of cardiac sympathetic innervation with the progression of cardiomyopathy in BIO 14.6 hamsters. The distribution of 201Tl was uniform in control hamsters and BIO 14.6 hamsters at all stages of cardiomyopathy. In contrast, a reduction in MIBG accumulation occurred in the endocardial region of the left ventricular free wall and the left ventricular aspect of the interventricular septum in BIO 14.6 hamsters at 3 and 8 months of age. Thus, there was an uncoupling of the left ventricular distribution of 201Tl and 125I-MIBG in BIO 14.6 hamsters. In addition, interstitial fibrosis was increased in the interventricular septum, the subendocardial region of the left ventricular free wall, and the right ventricular wall, which were the sites of reduced MIBG accumulation. This study shows that dual myocardial imaging with MIBG and 201Tl may be useful for investigating patients with cardiomyopathy.

3-Iodobenzylguanidine↗

Sustained changes in acetylcholine and amino acid contents of brain regions following microsphere embolism in rats.

The present study was undertaken to explore changes in neurotransmitters and neuromodulators of brain regions impaired by microsphere embolism-induced, sustained ischemia. Nine hundred microspheres (48 microns) were injected into the right internal carotid artery of rats, and the time course of changes in the triphenyltetrazolium chloride (TTC)-stained areas of their brain slices and acetylcholine and amino acid contents in the cerebral cortex, striatum and hippocampus of both hemispheres were determined. The TTC-unstained area, a measure of infarction, was developed in the right hemisphere by the 3rd day after the embolism, which was similar to that on the 28th day. A marked decline in acetylcholine content of these three regions of the right hemisphere was detected throughout the experiment (28 days). The glutamate, aspartate, GABA, and taurine levels were markedly decreased following microsphere-embolism. Most of these decreases were significantly attenuated during the first 5 days following the embolism, and they then partially recovered with time after the operation. Minor metabolic changes were observed in the left hemisphere. The results suggest that microsphere-embolism induces cerebral infarction and/or sustained damage to acetylcholine and neurotransmitter amino acid synthesis and/or catabolism of the brain regions. This model may provide information concerning the pathophysiological alterations in long-term cerebral ischemia and infarction.

Acetylcholine↗

The insulo-acinar portal and insulo-venous drainage systems in the pancreas of the mouse, dog, monkey and certain other animals: a scanning electron microscopic study of corrosion casts.

Scanning electron microscopy of vascular casts of the pancreas from monkies, cattle, pigs, dogs, cats, rabbits, guinea pigs and mice showed certain species differences in the occurrence of intralobular and interlobular islets and in the microcirculatory pattern of these islets. Interlobularly located islets were frequently found in the mouse and guinea pig, as has been previously established in the rat (Murakami and Fujita, 1992); they emitted insulo-venous efferent vessels directly draining into veins. In contrast, the intralobular islets in the guinea pig usually issued insulo-acinar portal vessels continuous with the lobular capillary network. In the mouse, they usually emitted both the insulo-acinar portal and insulo-venous efferent vessels. The insulo-venous efferent vessels, including those of the interlobular islets, could partly be portal in nature since they occasionally issued portal branches directed to the lobular capillary network. In rabbits, cats, dogs, pigs, cattle and monkies, as in men (Murakami et al., 1992), essentially all islets in the pancreas were intralobular in location and usually emitted the portal vessels only. In the mouse and rabbit, as in the rat (Murakami and Fujita, 1992), the islet received afferent vessels in its superficial aspect and issued efferent vessels from its deep aspect. In the Formosan monkey, as previously reported in the rhesus monkey (Fujita and murakami, 1973), the afferent vessels usually ran deep into the islet which emitted vessels from its superficial aspect. In other animals examined in this study, as in humans (Murakami et al., 1992), no consistent rule concerning the microcirculatory pattern within the islet could be determined.

Animals↗

Neurons with strongly negative-charged surface-coats in adult rat brain as detected by staining with cationic iron colloid.

Light microscopy of tissue sections stained either with cationic iron colloid (pH 1.0-2.0) and nuclear fast red or with this colloid and thionin showed that the adult rat brain contains a considerable number of neurons which are strongly negative-charged by being coated with sulfated proteoglycans such as chondroitin sulfates. These neurons are distributed mainly in the cerebral cortex, hippocampus, zona incerta, medial and lateral cerebellar nuclei, ventral pontine nuclei and certain other areas. In the hippocampal formation, the strongly negative-charged cells seem identical with the GABAergic inhibitory interneurons reactive to the lectin Vicia villosa agglutinin. Neurons, including the GABAergic Purkinje's cells, of the cerebellar cortex showed no reaction to our cationic iron colloid at pH values of 1.0-2.0. Many non-GABAergic pyramidal cells in the lamina ganglionalis of cerebral cortex and many non-GABAergic large neurons of the ventral pontine nuclei were highly reactive to our colloid at pH values of 1.0-2.0. This suggests that our cationic iron colloid at pH values of 1.0-2.0 mainly stains certain subtypes of GABAergic neurons as well as some non-GABAergic neurons projecting long associational or commissural fibers.

Animals↗

The occurrence in the human brain of neurons with strongly negative-charged proteoglycans.

The occurrence of neurons with strongly negative-charged surface-coats was confirmed in the human brain. Cerebral cortical tissue pieces (Area 19 of Brodmann), which had been removed in surgery from a 45-year-old Japanese man with meningioma were fixed with formalin. These specimens were cut into sections, stained with fine cationic iron colloid at pH value 1.0-2.0, treated for Prussian blue reaction, counter stained with carbolthionin, and observed with a light microscope. The observations indicated that some large-sized pyramidal cells in the ganglionic lamina were strongly negative-charged or coated with sulfated proteoglycans, though where these cells projected to could not be determined.

Brain Chemistry↗

Microcirculatory patterns in adult rat cerebral hypophysis: a scanning electron microscope study of replicated specimens.

The blood vascular bed of the cerebral hypophysis in the adult rat was replicated completely or incompletely by arterial injection of different amounts of methacrylate resin, to be observed with a scanning electron microscope. Complete replication confirmed our previous findings (Murakami et al., 1987) on the distribution and structure of the vascular beds in and around the hypophysis of the rat. One long major and several minor portal routes (vide infra) were reproduced sufficiently together with the systemic veins of the posterior lobe. Incomplete replication demonstrated that resin flows: 1) via the long portal vessels from the median eminence and neural stalk to the anterior lobe; 2) via the accessory long portal vessels from the subependyma to the anterior lobe; 3) via the short portal vessels from the posterior lobe to the anterior lobe; 4) via the neuro-intermedial portal vessels from the posterior lobe to the intermediate lobe; 5) via the intermedio-distal portal vessels from the intermediate lobe to the anterior lobe; and 6) via the tuberal portal vessels from the tuberal lobe to the anterior lobe. Incomplete replication also demonstrated that resin in the median eminence and neural stalk is drained preferentially into the anterior lobe via the long portal vessels, and that resin in the posterior lobe is drained mainly into the systemic veins. We were unable to demonstrate a retrograde resin flow from the anterior lobe to the median eminence, subependyma, neural stalk, intermediate lobe and posterior lobe, nor an ascending resin flow from the posterior lobe to the median eminence and subependyma. Also failing to be noted were an ascending resin flow from the hypophysis to the hypothalamus and a descending resin flow from hypothalamus to the hypophysis.

Animals↗

A hydrophilic resin-embedding method for light and electron microscopic detection of tissue anionic sites with cationic colloidal iron: as applied to mouse Paneth cells.

A cationic colloidal iron method was introduced for electron microscopic detection of anionic sites in hydrophilic resin-embedded specimens, and the method was applied to Paneth cells of the mouse jejunum. Mouse jejunal blocks were embedded in hydrophilic acrylic resin (LR White), cut into ultrathin sections, stained with the diluted cationic colloidal iron, and exposed to osmium vapor. The jejunal tissues, including the Paneth cells, embedded in hydrophilic resin were reactive to the fine cationic colloidal iron. At pH value 1.5, fine electron dense colloidal iron deposited along the rims of the secretory granules and the Golgi apparatus of the Paneth cell. Colloidal particles distributed on the osmiophilic reticular structures in the rim and in dot-like fashion lined the border between the granular core and rim. At pH value 4.0, ribosomes reacted to cationic colloidal iron particles in addition to the granular rims and Golgi apparatus. At pH 7.0, even the cores of the secretory granules were stained. Semi-thin sections prepared from the LR White-embedded specimens and stained at pH 1.5 with the diluted (1:3 in volume) cationic colloidal iron showed sufficient Prussian blue reaction for light microscopy in the rims of Paneth granules and mucus of goblet cells. This method is therefore useful for correlative light and electron microscopic detection of tissue anionic sites, including sulfate, carboxyl and phosphate groups, at various pH values.

Animals↗

The occurrence of rat spinal cord neurons with strongly negative-charged surface coats.

Light microscopy of tissue sections stained with cationic iron colloid (pH 1.0-1.5) showed that the adult rat spinal cord contains some neurons which are provided with strongly negative-charged surface coats. These neurons are distributed preferentially in the posterior and intermediomedial columns of the grey matter. The present study thus supplements our previous study of the rat brain (MURAKAMI et al., 1993b), and proves that the neurons with strongly negative-charged surface coats occur widely in the central nervous system of the adult rat.

Animals↗