Search PubMed⌕ Search

Biomedical subjects

K Kondo

Publications and source records attributed to K Kondo.

At least 469 records · Page 26Linked to original sources

Molecular cloning and characterization of avian N-methyl-D-aspartate receptor type 1 (NMDA-R1) gene.

Birds have several advantages in the study of memory formation, as imprinting and passive avoidance behaviors in chick are often used as model systems. However, the primary structure of the bird N-methyl-D-aspartate (NMDA) responsive glutamate receptor, which is assumed to play a critical role in memory formation, has not been determined. In this report we describe the cDNA cloning of a subunit of NMDA receptors (NMDA-R1) from duck and analysis of its structure and distribution in the brain. The N-terminal 898 amino acids of the NMDA-R1 were well conserved between duck and mammals, but the homology was completely lost in the C-terminus. In situ hybridization showed that the duck NMDA-R1 gene was expressed throughout the brain as it is in mammals.

Amino Acid Sequence↗

Experimental study on chemotherapy using adsorbent charcoal with CDDP administered directly into the mediastinum following esophagectomy.

In this study, 1500AA, an activated charcoal with a strong affinity for the lymphatic system, was examined for its ability to deliver chemotherapy to metastatic lymph nodes. First, the anticancer effect on metastatic lymph nodes was assessed in an experiment using the mouse mammary tumor, MM48. Pathological examination of the inguinal lymph nodes revealed a metastatic rate of 50% in the group given cisplatin (CDDP)-saline, but 20% in the group given CDDP-charcoal. Next, in a canine model, CDDP dissolved in normal saline was administered directly into the mediastinum, and CDDP was given with fine particles of activated charcoal in the same manner in the other group. The concentration of CDDP in the lymph nodes and the plasma rapidly increased to peak in 10 min in the CDDP-saline group, whereas it increased slowly to peak in 20-30 min in the CDDP-charcoal group. Moreover, the CDDP-charcoal group was found to have a much higher concentration of CDDP in the lymph nodes than the CDDP-saline group.

Adenocarcinoma↗

The effect of the neurokinin antagonist FK-224 on the cough response to inhaled capsaicin in a new model of guinea-pig eosinophilic bronchitis induced by intranasal polymyxin B.

Eosinophilic bronchitis without asthma can cause a persistent non-productive cough which is resistant to bronchodilator therapy. To understand the mechanism of the cough in this disorder, an animal model of eosinophilic bronchitis was developed. Guinea-pigs were treated with transnasal administration of polymyxin B or saline twice a week for 3 weeks. The number of eosinophils in bronchoalveolar lavage fluid increased in polymyxin B-treated animals when compared with those treated with saline. In addition, histological examination showed that the number of eosinophils infiltrated into the tracheal epithelium increased; injury to the tracheal epithelium was greater in polymyxin B-treated animals. The numbers of coughs induced by saline and each concentration of capsaicin (10(-18), 10(-16), 10(-14) M) were greater in the polymyxin B-treated animals. FK-224 (a neurokinin receptor antagonist) decreased the heightened cough reflex in this animal model of eosinophilic bronchitis. These findings suggest that neuropeptides, and particularly neurokinins, are involved in the heightened cough receptor sensitivity in eosinophilic bronchitis without asthma. This has implications for better understanding of this disorder and its treatment.

Administration, Inhalation↗

Pelvic actinomycosis presenting with a rectal stricture: report of a case.

We present herein the case of a patient with actinomycosis involving the pelvic cavity, who presented with a rectal stricture. It is rare for this type of actinomycosis to be accurately diagnosed preoperatively, but a precise diagnosis, made using needle biopsy guided by computed tomography allowed for successful treatment by resection of the granulation tissue surrounding the rectal stricture through a transsacral approach.

Actinomycosis↗

Effects of alcohol on lipoprotein lipase, hepatic lipase, cholesteryl ester transfer protein, and lecithin:cholesterol acyltransferase in high-density lipoprotein cholesterol elevation.

The mechanism whereby alcohol increases high-density lipoprotein cholesterol (HDL-C) levels is unclear. Lipoprotein lipase (LPL), hepatic lipase (HL), cholesteryl ester transfer protein (CETP) and lecithin:cholesterol acyltransferase (LCAT) act on lipoprotein metabolism. The purpose of the present study is to determine which one or what combination of these factors is responsible for the rise in HDL-C levels following alcohol ingestion. After 3 weeks of abstinence, 12 men consumed 0.5 g/kg bw of alcohol per day for 4 weeks; 13 abstaining men served as controls. Mean plasma total cholesterol (TC) levels were unchanged in either group throughout the study. Among the alcohol consumers, plasma triglycerides (TG), HDL-C, apolipoprotein (apo) A-I and A-II levels increased significantly after 3 weeks of alcohol loading but were unchanged in the control group. High-density lipoprotein3 cholesterol (HDL3-C) levels increased significantly in the alcohol consumers after 4 weeks of alcohol loading whereas high-density lipoprotein2 cholesterol (HDL2-C) levels were unaffected. In the controls, neither HDL2-C nor HDL3-C changed significantly. Post-heparin plasma (PHP) LPL activity and mass increased significantly (P < 0.01) after the alcohol ingestion (controls remained unchanged) without changing LPL specific activity. HL, CETP and LCAT activities were unaffected in both groups. We conclude that of the factors considered, LPL contributed the most to the alcohol-induced rise in HDL-C.

Adult↗

Expression of pi-glutathione S-transferase gene (GSTP1) in gastric cancer: lack of correlation with resistance against cis-diamminedichloroplatinum (II).

Class pi-glutathione S-transferase (GSTP-1) is one of several factors proposed to affect drug sensitivity to cisdiamminedichloroplatinum (II) (CDDP). It has also been investigated as a potential marker for the serodiagnosis of various types of cancers. In this study, attempts were made to quantify mRNA levels of the enzyme in healthy and cancerous gastric mucosa specimens, and to evaluate their significance in inherent drug resistance to CDDP. Thirty gastric cancer specimens were analysed by northern blotting with radiolabelled GSTP1 cDNA. Of these, the chemosensitivities of 22 specimens were evaluated by the succinic dehydrogenase inhibition (SDI) test. GSTP-1 mRNA was detected in all the specimens, with slightly increased, but non-significant expression in the neoplasms. Comparison of these drug sensitivities with results of northern blotting analysis showed no inverse correlation, as was expected from the widely investigated role of the enzyme in drug resistance.

Blotting, Northern↗

Epstein-Barr virus-associated large granular lymphocyte leukemia with cutaneous infiltration.

A 36-year-old man had a high titer of antibody to Epstein-Barr virus (EBV) and recurrent necrotizing papules and nodules on his face and oral mucosa. The disease was diagnosed as CD3+4- 8+ large granular lymphocyte leukemia of T-cell origin. Southern blot analysis demonstrated that EBV DNA was present in CD8+ lymphocytes; EBV antigens were also observed in these lymphocytes. These findings demonstrated that EBV latently infected the leukemic cells and may have played a role in the pathogenesis of this disease. This is the first report of an association between EBV and large granular lymphocyte leukemia of T-cell origin.

Adult↗

Isolation, characterization and epistasis of fluoride-resistant mutants of Caenorhabditis elegans.

We have isolated 13 fluoride-resistant mutants of the nematode Caenorhabditis elegans. All the mutations are recessive and mapped to five genes. Mutants in three of the genes (class 1 genes: flr-1 X, flr-3 IV, and flr-4 X) are resistant to 400 micrograms/ml NaF. Furthermore, they grow twice as slowly as and have smaller brood size than wild-type worms even in the absence of fluoride ion. In contrast, mutants in the other two genes (class 2 genes: flr-2 V and flr-5 V) are only partially resistant to 400 micrograms/ml NaF, and they have almost normal growth rates and brood sizes in the absence of fluoride ion. Studies on the phenotypes of double mutants showed that class 2 mutations are epistatic to class 1 mutations concerning growth rate and brood size but hypostatic with respect to fluoride resistance. We propose two models that can explain the epistasis. Since fluoride ion depletes calcium ion, inhibits some protein phosphatases and activates trimeric G-proteins, studies on these mutants may lead to discovery of a new signal transduction system that controls the growth of C. elegans.

Animals↗

Telemedicine using mobile satellite communication.

With a view to providing paramedical care within moving vehicles, a telemedicine technique using mobile satellite communication was proposed. With this technique, the diagnosis from a specialist and the emergency care under his/her instructions would be available on the spot without unnecessary delay. The characteristic problems of this technique were identified as: channel capacity, size of the system, reliability of vital sign transmission, real-time operation and electromagnetic interference. Measures against these problems were devised, and their effectiveness was analyzed. A data format was designed and an experimental system was developed. The system can simultaneously transmit a color image, an audio signal, 3 channels ECG and blood pressures from a mobile station to a ground station. It can transmit an audio signal and error control signals from a ground station to a mobile station in a full duplex mode. Fundamental transmission characteristics were measured in a fixed station. Finally, experiments of medical data transmission were conducted with a navigating ship and an aircraft flying an international route. The measured threshold values of C/N(o) to guarantee satisfactory data reception were well below the lower boundary of C/N(o) of the communication link. Consequently, the feasibility of this technique was verified.

Aircraft↗

Variation of DNA sequence in immediate-early gene of human herpesvirus 6 and variant identification by PCR.

The complete nucleotide sequence of one of the immediate-early genes of human herpesvirus 6 variant B was determined and compared with that of variant A reported by Martin et al. (M.D. Martin, J. Nicholas, B. J. Thomson, C. Newman, and R. W. Honess, J. Virol. 65:5381-5390, 1991). While it was reported that two open reading frames exist in this region of variant A, only one open reading frame was found in variant B and the putative coding region of variant B was 2,679 nucleotides long. Furthermore, two additive regions of 108 and 228 bp were found in variant B. Primers covering one of these regions deleted in variant A were synthesized and used for PCR amplification. Twelve isolates from patients were clearly classified into variants A and B by PCR amplification with these primers. All isolates from patients with exanthem subitum were variant B.

Amino Acid Sequence↗

Microwave ablation of the atrioventricular junction in vivo and ventricular myocardium in vitro and in vivo. Effects of varying power and duration on lesion volume.

Catheter ablation in ventricular tachycardia has achieved only limited success using direct current (DC) and radiofrequency (RF) energy, due to either high complication rates or a limited lesion size. Microwave energy represents a possible alternative source of energy for percutaneous ablation of the ventricular myocardium. However, an optimal method for titration of the dose of microwave energy to achieve the desired lesion volume has not yet been established. The safety and efficacy of microwave ablation of the atrioventricular (AV) junction were studied in 11 dogs in vivo. The relationship between lesion size following microwave ablation and the power output of or exposure duration to microwave energy was also examined at disparate sites in each superfused left ventricular epicardium in vitro. To observe the pathologic changes in the myocardium after microwave ablation, microwave ablation of the endocardium of the left ventricle was carried out in 9 dogs in vivo. Complete AV block was achieved in 10 of the above 11 dogs with a mean of 5 applications of microwave energy. The lesion volume in vitro demonstrated a parallel increase with power (r = 0.76) and duration (r = 0.81). The mean lesion volume at 30 sec was: at 10W, 0.8 +/- 1.6; 20 W, 34.7 +/- 10.3; 30 W, 34.7 +/- 22.4: 40 W, 64.7 +/- 64.4; 50 W, 87.2 +/- 42.3; 60 W, 85.8 +/- 38.1; 70 W, 124.7 +/- 36.5; 80 W, 134.2 +/- 49.0 mm3. The mean lesion volume at 80 W was: at 15 sec, 32.6 +/- 37.8; 30 sec, 101.2 +/- 46.4; 60 sec, 180.6 +/- 80.1; 120 sec, 291.8 +/- 122.7; and 180 sec, 459.3 +/- 204.6 mm3. The ablated lesions showed discrete, homogeneous coagulation necrosis with sharp margins from the adjacent normal myocardium. Microwave energy may thus be more effective than RF energy, and have a lower risk of complications and arrhythmogenesis than DC energy when used for ablation in ventricular tachycardia.

Animals↗

Establishment of new inbred strains derived from Japanese wild rats (Rattus norvegicus).

Inbreeding of Japanese wild rats (Rattus norvegicus) resulted in five new strains. The conception rates of wild rat strains were lower than those of inbred laboratory strains, and maternal aggressiveness was observed in some wild strains. The body size of domesticated animals was larger than that of captured ancestors. Two strains have been established as inbred strains; the MITA strain has been tamed to the level of laboratory rats, while the nature of the MITD strain is wild. The MITB strain was derived from the MITA strain as a coat color variant. The MITC and MITE strains have been bred to the F15 and F11 generations, respectively. The new strains can provide new genetic variations against a wild type background and might be useful for physiological and psychological experiments.

Animals↗

[Adrenal cyst with an immunohistochemical evidence of mesothelial origin. Report of a case].

A case of adrenal cyst with an immunohistochemical evidence of mesothelial origin is presented. A 73-year-old Japanese woman was referred to our hospital with a complaint of left flank pain. The diagnosis of left adrenal cyst was made based on the radiographic and hormonal examinations. The adrenal cyst was removed surgically. Histological examination revealed that the cyst was lined with either a single layer of squamous or cuboidal cells. In immunohistochemistry testing, the cells were positive for keratin and carbohydrate antigen 125, while they were negative for epithelial membrane antigen, vimentin, desmin, and factor VIII related antigen. Thus, the present case was classified as epithelial cyst of mesothelial origin.

Adrenal Gland Diseases↗

C-peptide response to glucagon in type 2 diabetes mellitus: a comparison with oral glucose tolerance test.

C-peptide immunoreactivity (CPR) response during glucagon test (intravenous injection of 1 mg glucagon) was compared with CPR response during 75 g oral glucose tolerance test (oGTT) in 58 patients with newly-diagnosed, untreated type 2 (non-insulin-dependent) diabetes mellitus. Both tests were also repeated after blood glucose was well controlled with sulfonylurea or insulin in 17 patients. CPR secretory response was estimated by delta CPR, i.e. the difference between maximal and basal levels of CPR during each test. In the 58 untreated patients, the mean fasting plasma glucose (FPG) level was 12.8 +/- 0.6 mmol/L (M +/- SE), and there was no significant correlation between delta CPR during glucagon test and delta CPR during oGTT. The therapy for diabetes mellitus in 17 patients resulted in a fall in FPG (from 15.1 +/- 0.5 to 6.7 +/- 0.3 mmol/L) and a marked increase in delta CPR during oGTT (from 0.28 +/- 0.06 to 1.18 +/- 0.17 nmol/L, P < 0.01), but did not influence delta CPR during glucagon test (from 0.39 +/- 0.06 to 0.42 +/- 0.06 nmol/L, N.S.). In these patients, delta CPR during glucagon test before therapy correlated significantly with delta CPR during oGTT after therapy. Of the 13 patients who showed impaired CPR response during oGTT (delta CPR < 0.5 nmol/L) but substantial response during glucagon test (delta CPR > or = 0.5 nmol/L), 12 were successfully controlled without insulin therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗