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Biomedical subjects

K Abe

Publications and source records attributed to K Abe.

At least 469 records · Page 26Linked to original sources

Production of LLU-alpha following an oral administration of gamma-tocotrienol or gamma-tocopherol to rats.

An oral administration of gamma-tocotrienol (gamma-T3) or gamma-tocopherol (gamma-Toc) to male rats caused an increase of the concentration of 2,7,8-trimethyl-2-(beta-carboxyethyl)-6-hydroxy chroman (LLU-alpha, gamma-CEHC), a natriuretic compound, in plasma with a T(max) of 9 h. The configuration at C-2 of LLU-alpha produced from gamma-T3 or gamma-Toc was assigned as S-form by an HPLC equipped with a chiral column. These data indicated that LLU-alpha was produced not only from gamma-Toc but also gamma-T3, without racemization at C-2 in rats.

Animals↗

Evaluation of L-glutamate clearance capacity of cultured rat cortical astrocytes.

Astrocytes have a function in the uptake of excitatory neurotransmitter L-glutamate via the glutamate transporter. To evaluate the L-glutamate clearance capacity of astrocytes, we developed a colorimetric method for the determination of L-glutamate concentration and measured changes in extracellular L-glutamate concentration in rat cortical astrocyte cultures. When L-glutamate (50-200 microM) was added to astrocyte cultures and incubated for 1-8 h, the extracellular L-glutamate concentration declined with time. When L-glutamate was mixed with astrocyte culture supernatants only, no significant change in L-glutamate concentration was observed, ruling out the possibility that L-glutamate is spontaneously or enzymatically degraded in the extracellular space. Alternatively, the time-dependent decline of extracellular L-glutamate concentration was blocked by the presence of glutamate uptake inhibitors, indicating that the glutamate uptake system of astrocytes plays a major role in the clearance of extracellular L-glutamate.

Animals↗

The scopolamine-induced impairment of spatial cognition parallels the acetylcholine release in the ventral hippocampus in rats.

We investigated the relationship between the induction of spatial cognition impairment in the 8-arm radial maze task and regional changes (ventral hippocampus (VH), dorsal hippocampus, frontal cortex, and basolateral amygdala nucleus) in brain acetylcholine (ACh) release using microdialysis in rats treated with muscarinic (M) receptor antagonists. In a behavioral study, two M1 antagonists, scopolamine (0.5 mg/kg, i.p. and 20 microg, i.c.v.) and pirenzepine (80 microg, i.c.v.), but not an M2 antagonist, AF-DX116 (40-80 microg, i.c.v.), disrupted spatial cognition in the 8-arm radial maze task. In brain microdialysis with Ringer's solution containing 0.1 mM eserine sulfate, scopolamine and AF-DX116, but not pirenzepine, increased ACh release in the VH. Moreover, in the bilateral injection of scopolamine (2 microg/side), the VH and dorsomedial thalamus nucleus were important regions for scopolamine-induced impairment of spatial cognition. A simultaneous determination of the behavioral changes revealed that scopolamine (0.5 mg/kg, i.p.) markedly decreased the ACh contents and also increased the ACh release in all regions tested. Especially, the changes in the ACh release of the VH closely paralleled the induction of the scopolamine-induced impairment of spatial cognition. These results suggest that the blocking balance between M1 and M2 muscarinic receptor in the VH therefore plays a major role in the spatial cognition impairment induced by scopolamine in the 8-arm radial maze task.

Acetylcholine↗

Addition of signal leader sequences to the N-termini of olfactory receptor proteins enhances their expression in Xenopus oocytet.

Several recent papers have reported the difficulties in expressing olfactory receptor proteins (ORs) in heterologous systems, and proposed that some sequences in ORs have negative effects on their efficient expression. To obtain an efficient expression system of ORs, we modified N-terminal sequences of ORs through the addition of exogenous sequences. Three kinds of sequences, designated as 5HT, V, and VL, were used. 5HT and V corresponded to the signal leader (SL) sequences of 5HT 3R and VIPR, respectively. VL corresponded to the first extracellular region of VIPR containing the SL sequence and three potential asparagine- (Asn-) linked glycosylation sites. The myc epitope was also added to the C-termini of the sequences. Several ORs including 17 of rat, GUST43 of rat, Y1 of medaka, FOR1-3 of pufferfish, 47E of carp, and ODR-10 of nematode were subjected to the modifications, and the RNAs encoding modified ORs were injected into Xenopus oocytes. The membrane fraction of the oocytes were analyzed by Western blotting to examine the expression of the proteins. In the cases of ORs modified with 5HT and V, only ODR-10 and 47E, both of which have more than two Asn-linked glycosylation sites in their extracellular regions, were detected as the bands of predicted molecular weights. On the other hand, most of the ORs modified with VL showed the bands of predicted molecular weights. These results suggest that SL sequences together with potential Asn-linked glycosylation sites have positive effects on the expression of ORs in heterologous systems.

Amino Acid Sequence↗

Characterization of a vitamin B12 compound in the edible purple laver, Porphyra yezoensis.

The edible purple laver, Porphyra yezoensis, contained 51.49+/-1.51 microg of vitamin B12 compounds per 100 g dry weight of the laver (mean +/- SEM, n = 4). A vitamin B12 compound was purified from the lyophilized purple laver and partially characterized. The silica gel 60 TLC and reversed-phase HPLC patterns of the purified pink-colored compound were identical to those of authentic vitamin B12, but not to those of vitamin B12 analogues inactive for humans.

Biological Availability↗

Control of blood pressure and lifestyle-related risk factors in elderly Japanese hypertensive subjects.

The aim of this study was to analyze the treatment of elderly hypertensive patients by Japanese physicians specializing in hypertension. We enrolled 939 patients with hypertension who were treated in the outpatient clinics of 11 hospitals in 1995; 793 of these patients (388 men and 405 women; mean age, 66.6+/-9.0 years) received follow-up examinations in 1996, and the data on these patients was used for the present analysis. Blood pressure (BP), body mass index, lifestyle, and laboratory data were analyzed in all patients. The average BP was 143+/-16/81+/-10 mmHg in 1995 and 142+/-15/80+/-10 mmHg in 1996. The patients whose baseline BP was at the level of Grade 2 or 3 in the WHO-ISH classification (n=117) were characterized by a higher women-to-men ratio, higher age, a higher serum total cholesterol concentration, and higher QRS voltage. In these patients, from 1995 to 1996, the average BP significantly decreased, whereas fasting plasma glucose, serum total cholesterol and serum creatinine concentrations showed only negligible changes. In 220 patients (28%), BP was <140/<90 mmHg at both the initial and the follow-up examinations, whereas 351 patients (44%) were hypertensive in both 1995 and 1996. Thirty-three percent of the patients were smokers. More smokers than nonsmokers had had prior cardiovascular events, diabetes mellitus, or overt proteinuria. In conclusion, the average BP level among the patients treated by Japanese physicians specializing in hypertension was somewhat higher than that recommended by WHO-ISH Guidelines (1999). Patient education to control lifestyle-related risk factors, particularly to stop smoking, should be emphasized.

Aged↗

Myositis as a manifestation of chronic graft-versus-host disease.

We report a 22-year-old man who had myositis in the course of chronic graft-versus-host disease after bone marrow transplantation for acute monocytic leukemia. The distribution of muscular involvement was different from idiopathic polymyositis. Muscular atrophy and weakness were noted in the distal muscles as well as in the proximal muscles of the upper extremities but there was little weakness in the proximal muscles of the lower extremities. However, histological and immunohistochemical study of the biceps brachii muscle showed findings similar to those of idiopathic polymyositis. It was suggested that myositis can be a manifestation of chronic GVHD caused by a cellular immune reaction by donor T cells.

Adult↗

Tentorial meningioma associated with pathological laughter--case report.

A 33-year-old male presented with involuntary and inappropriate laughter. Neuroimaging revealed a meningioma ventrolateral to the pons and midbrain, attached to the medial middle tentorium on the left side. The pathological laughter ceased immediately after subtotal removal of the tumor. Pathological laughter may be an early focal sign of a mass compressing ventrolateral brainstem.

Adult↗

Immunoreactivity to various human cytochrome P450 proteins of sera from patients with autoimmune hepatitis, chronic hepatitis B, and chronic hepatitis C.

Numerous human Cytochrome P450 enzymes (CYPs) associated with 'phase I' drug metabolism have been identified. Among them, CYP2D6 is thought to be the major target autoantigen to anti-liver kidney microsome (LKM)-1 autoantibody, a characteristic feature of autoimmune hepatitis (AIH) type II. In this study, we were able to clone CYP2D6 cDNA from a human liver cDNA library and express the CYP2D6 recombinant protein, and also to prepare four other representative human CYP proteins (CYP1A2, 2C9, 2E1, and 3A4). These preparations were used to assay the immunoreactivity of patients with AIH type I (n=35) and type II (n=9). As comparison groups, sera from patients with chronic hepatitis B (n=15), chronic hepatitis C (n=55; 24 anti-LKM-1-positive, 31 anti-LKM-1-negative), and from normal controls (n=30) were included. The five CYP proteins did not react with sera from normal controls nor from patients with chronic hepatitis B. CYP2D6 reacted with sera from 100% (9/9) of AIH type II patients, 79% (19/24) of patients with anti-LKM-1-positive chronic hepatitis C, and 6.5% (2/31) of patients with anti-LKM-1-negative chronic hepatitis C. In contrast, CYP1A2 reacted with serum from one patient with AIH type I, CYP2E1 reacted with sera from two patients with AIH type I, one patient with anti-LKM-1-positive chronic hepatitis C, and two patients with anti-LKM-1-negative chronic hepatitis C, and CYP3A4 reacted with sera from one patient with AIH type II and one patient with anti-LKM-1-positive chronic hepatitis C. CYP2C9 did not react with any of the sera included in this study. From these results, it is suggested that CYPs other than CYP2D6 can function as immunotargets in certain disease conditions.

Adult↗

Use of real-time PCR to monitor human herpesvirus 6 reactivation after allogeneic bone marrow transplantation.

Reactivation of human herpesvirus 6 (HHV-6) is common following allogeneic marrow transplantation, however, little is known about the immune control and pathogenic potential of HHV-6 infection after transplantation. In order to determine whether reactivation of HHV-6 plays an important role in the development of complications in patients undergoing allogeneic bone marrow transplantation or not, we developed a very rapid quantification of viral DNA using a LightCycler. The amount of viral DNA was determined using a supernatant of a chronically infected cell line [TaY(OK)] which contains a known amount of viral DNA. Peripheral blood cells were collected from 5 patients undergoing allogeneic bone marrow transplantation once before transplant and once per week after transplant for 8-24 weeks. The real-time PCR system revealed that there was a linear correlation in the range of 101 to 105 molecules of reference. Using this system, we have found the presence of non-diagnosed HHV-6 reactivation as well as symptomatic infection, indicating the potential for routine implementation of this technology for laboratory diagnosis of HHV-6 infection. Our study shows that this method of rapid quantification of HHV-6 genomes by the real-time PCR using a LightCycler may be useful not only to understand the reconstitution of the immune system following marrow transplantation but also to manage the care of patients.

Adolescent↗

[Chemotherapy for unresectable recurrent or metastatic squamous cell carcinomas of the head and neck].

The efficacy of chemotherapy for unresectable recurrent or metastatic squamous cell carcinomas of the head and neck can not be proved by survival periods. However, the efficacy of chemotherapy has been observed in some select patients. We investigated the effect of chemotherapy for unresectable recurrent squamous cell carcinomas of the head and neck. Four patients with a good performance status (PS) were treated with high-doses of leucovorin (LV), cisplatin (CDDP), and 5-fluorouracil (5-FU). The regimen consisted of 25 mg/m2 of CDDP on days 1-5; 600 mg/m2 of 5-FU of days 2-6; and 200 mg/m2 of LV on days 1-6. Patients received 3 cycles of this regimen at 28-day intervals. Ten patients with a poor PS were treated with low-doses of CDDP and tegafur.uracil upon admission. The regimen of seven poor PS patients consisted of 8 mg/m2 of CDDP on days 1-5 and 8-12, and 400 mg/body of tegafur.uracil administered orally on days 1-14. The other three patients received chemotherapy on an outpatient basis for ten weeks. The weekly regimen consisted of 7.5 mg/m2 of CDDP on days 3 and 6 and 400 mg/body of tegafur.uracil administered orally on days 1-7. With respect to the LV + CDDP and 5-FU treatment, complete remission was obtained in one patient. Two patients showed no change (NC), while one patient developed a progressive disease (PD). This regimen is highly toxic, has severe side effects including myelosuppression, oral mucositis, and diarrhea, and has a survival period of between 16 and 32 weeks. The low-dose CDDP + tegafur.uracil treatment produced a partial response in three patients, NC in three patients, and four patients developed a PD. This regimen doses not have any severe side effects and has a survival period of between 4 and 67 weeks.

Aged↗

Genetic potential of interfacial guided osteogenesis in implant devices.

The purpose of this review is to summarise recent advances in the design and composition of bioactive surface layers of implantabile biomaterials, and thus the genetic potential of osteoprogenitor cells to recognize and respond to these diverse implanted biomaterials. Changes applied to a biomaterial's surface, in general, could improve its biocompatibility, osseointegration and durability properties, which are required for long-term implantation in the living body. In this review, the implant-bone interface was evaluated and interpreted on the basis of osteoblast cell cultures, i.e., on the genetic potential of osteoblasts to express different phenotype markers depending on the type of biomaterials used. The interface formed by in vitro-grown osteoblasts may be used to identify components of the in vivo implant-bone interface. Over the years, a large number of implant systems consisting of many different biomaterials have been introduced in dentistry and orthopaedics. This paper discusses the performance of currently used metals and other biomaterials, by focusing on the events which occur immediately after implantation and on their impact on the bone-implant interface. The review demonstrates that continuous improvements in composition, surface modality and design of implants may benefit osseointegration and clinical longevity of such implants. No load-bearing conditions or clinical status are discussed. Titanium (Ti) and calcium phosphate ceramics are regarded as the most biocompatible synthetic substances known to be used in hard tissue implantation. These biomaterials are osteoconductive, and do not induce ectopic bone formation. Nonetheless, they provide a physical matrix which is suitable for the deposition of new bone and may guide both the growth and extension of the bone. Comparative investigation evaluated that Ti implant systems appear to be apposed by more bone than ceramic systems, although alternatives concerning the type of Ti alloy and bioactive surface layer engineering, generate extremely diverse osseointegration results. Manufacturers have created an extensive range of inorganic or ceramic coatings on Ti implants in order to achieve better bone healing and osteoconduction. Biologically active molecules, added to the implant surface, represent breakthroughs in guided interfacial osteogenesis. This methodology offers an enormous potential of genetic controlling and promoting osteogenesis. The bone growth factors are not fully understood, but most researchers agree that the contact between the bioactive surface layer of the implant and bone is not static but dynamic and that the above factors may maximise the implant osseointegration.

Animals↗

Effect of intrathecal nocistatin on the formalin-induced pain in mice versus that of nociceptin/orphanin FQ.

The effect of intrathecal nocistatin on formalin-induced pain in mice was investigated and compared with that of nociceptin/orphanin FQ (Noc/OFQ) to get information on the functional relationship between nocistatin and Noc/OFQ in the spinal cord. Subcutaneous injection of formalin into the hindpaw induced biphasic pain behaviors. Nocistatin, 1 pg, given intrathecally 1 min before 2% formalin injection, significantly attenuated the first phase of the formalin-induced pain. Also, 10 to 1000 pg of nocistatin, given 10 min after formalin injection, significantly inhibited the second phase of the formalin test. Naloxone, 5 mg/kg i.p., failed to antagonize inhibitory effects of nocistatin on either phase of the formalin-induced pain, indicating that analgesic effects of nocistatin were unrelated to the classic opioid system. At 1 to 100 pg, Noc/OFQ exerted no influence on either phase of the 2% formalin-induced pain. However, at 1% formalin, Noc/OFQ significantly aggravated the second phase at 10 pg but not the first phase at 1 to 1000 pg. This aggravating effect of Noc/OFQ was completely reversed by 10 pg of nocistatin. At 0.3 and 1 microg, Noc/OFQ, but not nocistatin, significantly inhibited both phases of the 2% formalin-induced pain. Suppressive effects of 1 microg of Noc/OFQ on the formalin-induced pain were not affected by 1 microg of nocistatin. These results suggest that Noc/OFQ might be involved in the second phase of the mouse formalin test and that, under such pathophysiological conditions, nocistatin could exhibit antagonism against Noc/OFQ at the spinal level.

Animals↗

[Prediction of the clinical efficacy of hepatic arterial chemotherapy for metastatic hepatic cancer by intraarterial infusion of 99mTc-MIBI].

SPECT was performed in 11 patients with metastatic hepatic cancer by intraarterial infusion of 99mTc-MIBI before hepatic arterial chemotherapy was started, and the degree of accumulation and clinical efficacy were compared. Early and delayed SPECT images were obtained and various parameters were calculated, including early ratio (ER), delayed ratio (DR), washout rate (WR), and retention index (RI). Judgement of clinical efficacy was made by CT before and after hepatic arterial chemotherapy and was classified as effective, unchanged, and progressive groups. The mean values of ER and DR in the effective group were higher than those in the progressive group. No relationships were noted among the WR and RI values of the groups. The assessment of ER and DR using 99mTc-MIBI intraarterial SPECT is considered to be useful for prediction of the clinical efficacy of hepatic arterial chemotherapy for metastatic hepatic cancer.

Adult↗

Indirect evidence of TTV replication in bone marrow cells, but not in hepatocytes, of a subacute hepatitis/aplastic anemia patient.

The presence of a new DNA virus (TTV) has been reported in sera from patients with posttransfusion hepatitis of unknown etiology. The precise replication site of TTV, however, has not been established. In this study, the presence of TTV in liver autopsy material, and in bone marrow biopsy and autopsy samples taken from a subacute hepatitis/aplastic anemia patient was determined by PCR and Southern blot analyses. Liver cells were found to contain only TTV DNA and not mRNA. Bone marrow material, especially that taken at biopsy, contained high levels of TTV DNA. It is suggested that the TTV replication site was in the bone marrow rather than in the liver, and that TTV infection was the cause of this patient's aplastic anemia. The precise etiological association of TTV with hepatitis remains to be established.

Adult↗

[Cancer therapy and processing information].

The National Cancer Center Japan started to provide free, computer-based cancer information, through a service called the National Cancer Center--Cancer Information Service (NCC-CIS), to patients and their families, physicians and other health professionals via fax (telephone) and the Internet in 1996. NCC-CIS in Japanese is modeled on the Physician Data Query service produced by the National Cancer Institute in the United States and is produced from an independent standpoint adopted to the medical and social environment in Japan. NCC-CIS provides up-to-date cancer treatment information (staging, prognosis and state-of-the-art treatment by stage of disease), supportive care for each type of cancer, an image reference database, and a directory of organizations and lecture meeting reports in Japan in order to facilitate better understanding of cancer among people and support the decision-making process for physicians in order to achieve a reduction in cancer deaths.

Humans↗

[Acute myocardial infarction in elderly patients: medical and social problems].

The number of elderly patients with acute myocardial infarction has been increasing. However, the choice of treatment remains controversial. Medical records of 310 consecutive patients with acute myocardial infarction were reviewed. Two retrospective analyses were performed. 1) Patients were divided into the elderly group(70 years or more) and the younger group(under 70 years). In-hospital course and outcome were compared. 2) Pre-hospital performance status and living status were reviewed in the elderly group. Acute phase reperfusion therapy was performed in fewer patients in the elderly group(60.8% vs 71.9%, p < 0.01). The difference was most pronounced in cases of direct coronary angioplasty(28.6% vs 54.7%, p < 0.05). As a result, the rate of reperfusion success(74.8% vs 86.8%, p < 0.01) was lower in the elderly group. Moreover, the rates of in-hospital death(23.6% vs 6.8%, p < 0.005), pulmonary edema(20.3% vs 10.8%, p < 0.05), cardiogenic shock(11.9% vs 6.0%, p < 0.005), pneumonia(17.3% vs 3.0%, p < 0.005), and delirium(29.4% vs 12.0%, p < 0.001) were higher in the elderly group. Five patients in the elderly group and 3 patients in the younger group required rehabilitation because of worsened performance status. Six of them were non-reperfused patients. Elderly patients considered likely to become bed-ridden because of pre-existing physical disability at admission accounted for 28.9% of the total. Moreover, many elderly patients had poor support systems (8.4% were living alone, 21.0% were living only with their spouse or a child, 30.1% were widows or widowers). These results show that a lower acute phase reperfusion rate(especially angioplasty) resulted in a poor prognosis and worse performance status in elderly patients. Also 30% of patients were not good candidates for conventional treatment because of delirium, and that self-help in daily life is a fundamental goal for most elderly patients. Rapid and simple acute phase reperfusion, subsequent immediate mobilization, and early discharge are recommended for elderly patients with acute myocardial infarction.

Activities of Daily Living↗