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Biomedical subjects

T Kitagawa

Publications and source records attributed to T Kitagawa.

At least 181 records · Page 10Linked to original sources

A novel clonality assay for the mouse: application to hepatocellular carcinomas induced with diethylnitrosamine.

A polymerase chain reaction-based clonality assay was developed for mouse tumors and cellular proliferations of the mouse. This assay was based on a polymorphism of the phosphoglucokinase-1 (Pgk-1) gene on the X chromosome between two different mouse subspecies and the different methylation patterns of active and inactive X chromosomes. All 15 tumor cell lines examined showed one of the two allelic bands on gel electrophoresis, which is consistent with the theory that tumor cell lines are monoclonally derived. This suggests that the Pgk-1 system is useful for clonality studies that will give insight into cancer development. With this method, nine hepatocellular carcinomas were examined, and eight showed monoallelic patterns. The remaining tumor exhibited a biallelic pattern, which is suggestive of polyclonal origin; however, other possibilities are discussed.

Animals↗

Pharmacokinetics of intravenous adriamycin for anhepatic chemotherapy during liver transplantation.

Frequent recurrence of hepatocellular carcinoma after liver transplantation indicates the necessity to eliminate patients with advanced disease and combine transplantation with some form of perioperative adjuvant chemotherapy. This study was undertaken to elucidate adriamycin pharmacokinetics for anhepatic chemotherapy during liver transplantation. beagles of both sexes were allocated into two groups, controls (n = 4) and anhepatic animals with total hepatectomy under venovenous bypass (n = 5). In both groups, adriamycin was administered in 1 min at a dose of 1 mg/kg through the left antecubital vein and peripheral blood was obtained at intervals for up to 2 h to determine the plasma adriamycin levels. The animals were then sacrificed to determine tissue adriamycin levels in the liver, kidney, heart, lung, and skeletal muscle. Plasma adriamycin levels in anhepatic animals were significantly higher than those in controls at all measured time points after 10 min, resulting in a 50% reduction of the mean total body clearance of adriamycin compared with controls (P < 0.01). However, there was no statistically significant difference in adriamycin levels between the two groups for all measured tissues except for the liver. Despite the complete lack of hepatic function, anhepatic animals showed only a 50% reduction in total body clearance of adriamycin compared with normal controls, probably due to compensatory excretion from other organs such as the kidney. These results suggest that systemic chemotherapy with the standard dose of adriamycin may be tolerable during the anhepatic period of liver transplantation with enhanced tumoricidal effects on micrometastases.

Animals↗

Percutaneous hepatic venous isolation and extracorporeal charcoal hemoperfusion for high-dose intraarterial chemotherapy in patients with colorectal hepatic metastases.

The results of treating 12 consecutive patients with unresectable colorectal hepatic metastases with a hepatic arterial infusion of high-dose Adriamycin, 100-120 mg/m2, using hepatic venous isolation (HVI) and charcoal hemoperfusion (CHP) are reported herein. Adriamycin was administered over 5-15 min under extracorporeal drug elimination by HVI-CHP. HVI was percutaneously accomplished by either the double-balloon technique using a Fogarty occlusion catheter (8/22F) or a balloon-tipped catheter (16F). During the infusion, isolated hepatic venous blood was filtered by CHP and pumped into the left axillary vein. There were no lethal complications, and good hemodynamic tolerance to HVI-CHP was confirmed. Tumor liquefaction accompanied by a sharp decrease in serum carcinoembryonic antigen levels by more than 50% of pretreatment levels was observed in 6 of the 12 patients 1 month after treatment. Apart from chemical hepatitis, which developed in 11 (92%) of the patients, the Adriamycin toxicities were well controlled following the development of nausea and vomiting in 2 patients (17%), leukopenia < 2,000/mm3 in 3 (25%), and gastric ulcer in 1 (8%). These results indicate that this method is a safe and useful procedure for otherwise hazardous high-dose intra-arterial chemotherapy in patients with unresectable hepatic tumors.

Adult↗

Absence of the inferior vena cava in a patient with omphalocele: two-dimensional echocardiographic and cineangiographic findings.

We report an unusual form of absence of the inferior vena cava (IVC) in a patient with a repaired omphalocele. Two sets of bilateral paravertebral veins served as the channels of systemic venous return from the lower half of the body. These veins were narrower than typical azygos or hemiazygos continuation in the absence of the IVC, with the result that a catheter from the femoral vein could not reach the right atrium (RA). Other associated venous-side anomalies were present, including a chamber between the hepatic vein (HV) and RA, narrowing and angulation at the junction between the HV and the chamber, and a subaortic innominate vein. All these anomalies were demonstrated by two-dimensional and color Doppler echocardiography. The recognition of these venous anomalies is important for cardiac catheterization or IVC cannulation for cardiopulmonary bypass in patients with omphalocele.

Adult↗

A controlled ovarian hyperstimulation regimen involving intermittent gonadotropin administration with a "short" protocol of gonadotropin releasing hormone agonist for in vitro fertilization.

PURPOSE: To examine the effects of an intermittent injection regimen of exogenous gonadotropin for controlled ovarian hyperstimulation on follicular development and on in vitro fertilization (IVF) outcome, 120 women who were candidates for IVF received intermittent injection (II) or consecutive injection (CI) regimens with a "short" protocol (SP) or a "long" protocol (LP) of gonadotropin releasing hormone agonist (GnRHa). Pure follicle stimulating hormone (pFSH) was injected to the women in the II groups on the first, second, and fifth days of the stimulation cycle and every other day thereafter. The women in the CI groups received a daily injection of pFSH. An additional 16 patients who were treated with both II-SP and CI-LP were also analyzed. RESULTS: Although the cancellation rate in the II-LP group was higher than those in the other groups, follicular development and IVF outcomes in the II-SP group were similar to those in the CI groups. The number of injections in the II-SP group was about half that in the CI groups. CONCLUSIONS: These results indicate that an intermittent pFSH injection regimen with a "short" protocol of GnRHa may be beneficial for patients in terms not only of being a less painful treatment but also causing less physical and mental stress than daily injections.

Adult↗

Immunocytochemical localization of polyamines in the gastrointestinal tracts of rats and mice.

An immunocytochemical method using a recently produced monoclonal antibody (ASPM-29) with an antibody specificity to spermine (Spm) and spermidine (Spd) fixed in situ, was used to demonstrate an immunocytochemical localization of polyamine (PA) pools in the gastrointestinal tracts of rats and mice. High PA immunoreactivity was always found in the cytoplasm of cells not only at the cell proliferative zone or the precursor cell zone but also at the neighboring non-proliferative premature cell zone of the epithelium, and a gradient of decreasing PA levels was noticed from these cells to the fully mature differentiated gastric surface mucous cells and absorptive cells of the small and large intestines. Also, strong staining for PAs was seen in the cytoplasm of fully differentiated gastric chief cells and neurons of both the myenteric and submucous plexuses, whereas the nuclei of the cells remained virtually unstained. These results may suggest that PAs are closely associated with the high biosynthetic activity in the cells of the gastrointestinal mucosa of normal rats and mice. This seems to be consistent with the PA immunocytochemical results previously obtained for neoplastic cells and active protein- or peptide-secreting cells, including exocrine or endocrine cell types.

Animals↗

Intra-articular calcifying synovial sarcoma mimicking synovial chondromatosis.

A case of intra-articular calcifying synovial sarcoma of the right knee joint in a 27-year-old man is reported. Prior to admission the patient had been suffering pain in the right knee for 5 years. Plain radiographs showed multiple calcified densities in the anterior aspect of the right knee closely mimicking synovial chondromatosis. Histological examination revealed that the lesion was a synovial sarcoma with extensive calcification subjacent to the synovial surface. Although intra-articular calcifying synovial sarcoma is very rare, it is important to be aware of the fact that synovial sarcoma, as well as synovial chondromatosis, can be present as a calcified lesion in the joint cavity.

Adult↗

Effect of extracellular adenosine 5'-triphosphate on Ca2+ efflux from freshly isolated adult rat cardiomyocytes.

The effect of extracellular adenosine 5'-triphosphate (ATP) on Ca2+ efflux from freshly isolated adult rat cardiomyocytes was examined. ATP stimulated the efflux of 45Ca2+ from the cells in a concentration-dependent manner (0.01-1 mM). The 45Ca2+ efflux from the cells was also stimulated by adenosine-5'-O-(3-thiotriphosphate)(ATP-gammas) and alpha,beta-methylene-ATP and adenosine 5'-diphosphate, but not by adenosine 5'-monophosphate and adenosine. The ATP-stimulated 45Ca2+ efflux was not affected by deprivation of the extracellular Ca2+, but was dependent on the presence of extracellular Na+. These results indicate that ATP stimulates extracellular Na+-dependent 45Ca2+ efflux from freshly isolated adult rat cardiomyocytes, probably through its stimulatory effect on the plasma membrane P2 purinoceptors which may couple to Na+/Ca2+ exchange.

Adenosine↗

Physiological significance of plasma sulfoconjugated dopamine in patients with hypertension--clinical and experimental studies.

Sulfoconjugated catecholamines, especially dopamine sulfate, have recently attracted much attention because of the possibility of their conversion to active free dopamine by tissue arylsulfatase. In the present study, we have measured the plasma levels of free and sulfoconjugated dopamine in patients with hypertension and have investigated the physiological significance of sulfoconjugation. Results showed that the plasma level of dopamine sulfate in patients with essential hypertension was higher than the level in control subjects, and was highest in patients with renal hypertension. However, the plasma level of free dopamine showed no significant difference between patients with hypertension and normal subjects. Moreover, after normalization of blood pressure in hypertensive patients with medication, the plasma levels of conjugated dopamine decreased to almost the control value. In the experimental study, dopamine sulfate inhibited angiotensin II-induced aldosterone release from bovine adrenal cortical cells to a similar extent as produced by free dopamine. From these results, we have concluded that plasma sulfoconjugated dopamine may regulate free dopamine in the plasma of patients with hypertension, and it may have some physiological effects on blood pressure regulation.

Adrenal Cortex↗

Isolation and characterization of a TATA-less promoter for the human RAG-1 gene.

Human recombination activating gene-1 (RAG-1) genomic DNA clones containing the first exon coding for the 5' untranslated region and the second exon coding for the remaining 5' untranslated region, coding region, and 3' untranslated region were cloned. Primer extension analysis and RNase protection analysis demonstrated the multiple RAG-1 transcription start sites, clustered in a 31 nucleotide (nt) region. Sequence analysis showed that the RAG-1 promoter lacked a TATA box as well as an initiator sequence. Transient expression assays using a luciferase reporter gene with truncated promoter fragments and substitution mutants, showed that the 5' promoter region containing the CCAAT box between -110 and -86, is indispensable for its basal promoter activity in RAG-1 expressing Nalm 6 cell line. Comparative transient expression assays in various cell lines revealed that the 854 nt upstream promoter region was active, not only in RAG-1 expressing cell lines but also in RAG-1 non-expressing cell lines. These data indicate that the 854 nt upstream region of RAG-1 gene confer basal promoter activity, and that the tissue- and stage-specific expression of RAG-1 is controlled by elements present outside of the promoter region and/or differential chromatin structure(s) of the individual cells.

Base Sequence↗

Development of a competitive enzyme-linked immunosorbent assay for diethylcarbamazine.

A sensitive and reproducible competitive enzyme-linked immunosorbent assay (ELISA) for the determination of the concentration of diethylcarbamazine (DEC) in biological fluids was developed. Since DEC has no functional group to conjugate with bovine serum albumin (BSA), N-(2-aminoethyl)-N-ethyl-4-methyl-1-piperazinecarboxamide (DEC-NH2) was first synthesized. This compound was then converted to carboxyl DEC (DEC-COOH) and conjugated to BSA and to poly-L-lysine for use as immunogen and solid-phase marker, respectively. The competitive ELISA was conducted by simultaneously incubating DEC with mouse anti-DEC antiserum over DEC-poly-L-lysine solid phase. Subsequently, the binding of anti-DEC antibody was detected by using sheep anti-mouse IgG peroxidase conjugate as a tracer. The reliability, determined by the coefficient of variation for inter and intra-assay, was satisfactory. The cross-reactivities of anti-DEC antibodies with DEC metabolites, related compounds and ivermectin were negligible. Using this assay, DEC levels were easily determined in serum of Mongolian jirds (Meriones unguiculatus) up to 4 hours following a single dose of DEC citrate base (100 mg/kg of body weight) via intraperitoneal route.

Animals↗

Successful pregnancy after intracytoplasmic injection of a single testicular spermatozoon into a human oocyte: a case report.

Testicular sperm was retrieved from a man with an epididymal obstruction, and an intracytoplasmic sperm injection was made into his wife's oocytes. In 4 mature oocytes treated, 2 fertilized eggs were obtained, and a clinical pregnancy was established with embryo transfers. Our experience demonstrated the possibility of fertilization and conception with testicular sperm.

Adult↗

Specificities of five kinds of antisera produced against crude drugs, pinella tuber, hoelen, glycyrrhizae radix, trichosanthes root and panax ginseng.

Five kinds of rabbit antisera produced against five kinds of crude drugs, Pinella Tuber, Glycyrrhizae Radix (GR), Trichosanthes Root, Hoelen, and Panax Ginseng, and five kinds of extracts of the same crude drugs were prepared. Specificity of each antiserum was demonstrated by two immunological methods for analyses, the selected antibody enzyme immunoassay (SAEIA) and western blotting, and five crude drug extracts as specimens. Each crude drug extract contained characteristic antigen specific to the corresponding antiserum. Characteristic antigens were suggested as protein components. Characteristic antigen of the crude drug GR was separated from GR extract by three chromatographic procedures and a protein component was separated. The separated protein was successfully applied to develop a SAEIA method applicable for specific assays of both the separated protein and GR extract.

Animals↗

Allelotype analysis in mouse hepatocellular carcinomas; frequent homozygous deletion of mouse homolog of p16/CDKN2 gene on chromosome 4 in culture.

Because allelotype analysis of many tumors has been important in the identification of new tumor suppressor genes, here we have analyzed hepatocellular carcinomas (HCCs) derived from F1 hybrid mice between C3H and MSM in detail. The analysis showed no allelic loss in primary HCCs, while the loss was detected in tumor cell lines established from HCCs. Recently, a candidate tumor suppressor gene termed p16/CDKN2, which was located near the interferon gene cluster on human chromosome 9p21, was identified by virtue of its frequent homozygous deletion in cell lines derived from many different tumor types. Since frequent allelic imbalances in the D4MIT9 locus and loss of heterozygosity in the alpha-interferon gene which was located near the mouse homolog of p16/CDKN2 (mouse p16) gene were detected in tumor cell lines, we investigated homozygous deletion of the mouse p16 gene by the comparative multiplex PCR method. The analysis revealed frequent homozygous deletion of the gene in thirteen of the tumor cell lines (13/25, 52%), but not in primary HCCs (0/25, 0%). These data indicate that gene deletions including the mouse p16 gene on chromosome 4 in tumor cell lines occur during the culture and that allelic imbalances are uncommon in mouse primary HCCs. Our results suggest that mouse p16 plays an important role in mouse hepatocarcinogenesis in vivo in progression or immortalization in vitro.

Alleles↗

A new method for the detection and quantitative measurement of the contents of trichosanthes root component composing Chinese traditional medicines.

A new method was developed to estimate the content of Trichosanthes root (TR) component in two Chinese traditional medicines. Characteristic antigens of TR were separated from TR extract using rabbit antiserum specific for TR, a dried root tuber of Trichosanthes kirilowii. Two selected antibody enzyme immunoassay (SAEIA) methods, the SAEIA A for assay of TR extract and the SAEIA B for assay of karasurin A were used as detection methods for the separation of TR antigens. Using several column chromatographies, two kinds of TR antigens, a protein component and a glycan component, were separated from TR extract. A SAEIA C method for assay of TR glycan component was developed using biotinylated second antibody and peroxidase-labeled avidin as the detection method. The SAEIA C was also found applicable for specific assay of TR extract as well as for the contents of TR component present in two Chinese traditional medicines, prescriptions of which contained TR. Content of trichosantin, an abortifacient protein component of T. kirilowii, in both the medicines were also measured by applying the SAEIA B for assay of karasurin A. Little trichosantin was found in either medicine and the reason for this was determined.

Antibodies↗

Synthesis and release of glycosylated prolactin in transfected cells with human prolactin complementary deoxyribonucleic acid.

To analyze how the synthesis and release of glycosylated PRL (G-PRL) is regulated, we transfected human PRL complementary deoxyribonucleic acid (cDNA) into three different cell lines consisting of GH3 cells that originated in rat pituitary tissue, Chinese hamster ovary cells, and COS-1 cells generated from monkey renal tissue. 35S-labeled PRLs produced by the cells were immunoprecipitated with anti-human PRL antiserum, and the ratios of G-PRL to total PRL were compared. PRLs of 23 kDa and 25 kDa were detected in the cell lysate and medium. The 25-kDa PRL was confirmed to be a glycosylated form by endoglycosidase treatments. The ratios of G-PRL/total PRL were 0.17-0.33, which were similar in lysates and media and among different cell lines. Pulse-chase experiments revealed that the autonomaous secretion rates of G-PRL and non-glycosylated PRL were almost identical. These results indicate that synthesis and secretion kinetics of human PRL may not be affected by its glycosylation in the cells transfected with PRL cDNA.

Animals↗

Simple and sensitive enzyme-linked immunosorbent assay for ivermectin.

A sensitive and reproducible enzyme-linked immunosorbent assay (ELISA) for the determination of the concentration of ivermectin (IVM) in biological fluids was developed. A conjugate of IVM on bovine serum albumin and poly-L-lysine was used to produce antibodies in rabbits and served as a solid-phase marker for titration of antibodies, respectively. The competitive ELISA was conducted by simultaneously incubating IVM and IVM-biotin conjugate with anti-IVM antiserum over goat anti-rabbit IgG (Fc) and then determining the amount of bound IVM-biotin with avidin-peroxidase conjugate as a tracer. The coefficient of variation for the assay was less than 10% in the range of 0.3-10 ng/ml. The limit of detection was 0.1 ng/ml. The cross-reactivities of anti-IVM antiserum with some anthelmintic drugs were negligible. Using this ELISA, serum levels of IVM were easily determined in Mongolian jirds (Meriones unguiculatus) up to 72 hr following a single oral dose of 500 microgram/kg of body weight.

Animals↗

Does epididymal length in men with congenital bilateral absence of the vas deferens have a correlation with the fertilization rate of epididymal sperm retrieved by micropuncture technique?

To investigate whether the variable length of the epididymis in men with congenital bilateral absence of the vas deferens (CBAVD) might have a correlation with fertilization and pregnancy rates in in vitro fertilization (IVF) treatment, we conducted a retrospective study involving a total of 60 CBAVD patients. All patients in this study had epididymal micropuncture in conjunction with perivascular nerve stimulation as part of the IVF program at the Nagoya University Hospital Reproduction Center. The patients were classified into 3 groups: group I consisted of patients having only a proximal portion of the caput epididymidis with a length of between 0.5 and 1.9 cm, group II consisted of patients with the caput and a portion of the corpus epididymidis with a length of between 2.0 and 4.0 cm, and group III consisted of patients with the caput, corpus and cauda of the epididymis measuring more than 4.0 cm. There were no differences in the sperm count, progression and normal morphology among the 3 groups; however, the motility was progressively higher in patients with a longer epididymis (12% in group 1, 18% in group II and 31% in group III). It was evident that group III showed the highest fertilization and pregnancy rate per patient (23% and 28%, respectively) among the 3 groups. This study shows that epididymal sperm from CBAVD patients with a longer epididymis have a higher IVF rate than CBAVD patients with a shorter epididymis.

Epididymis↗