Biomedical subjects

Kenji Suzuki

Publications and source records attributed to Kenji Suzuki.

At least 37 records · Page 2Linked to original sources

PubMed2006

[A case of systemic lupus erythematosus associated with thrombotic thrombocytopenic purpura and hemophagocytic syndrome].

THE CASE: A 44-year-old female. Developed polyarthralgia in August 2002. The patient was diagnosed with systemic lupus erythematosus (SLE) in November, due to polyarthralgia, leukopenia, anti ds-DNA antibody positive, antinuclear antibody positive, and false positive serologic test for syphilis. Hypocomplementemia continued even after the steroid treatment was conducted with insufficient control. In November 2003, ran fever and observed polyarthralgia. In December, gross hematuria and purpura appeared. The patient was hospitalized on December 25. Thrombotic thrombocytopenic purpura (TTP) was suspected from the emergence of fragmented red cells, hemolysis, thrombocytopenic purpura, headache, renal dysfunction and fever. As hemophagocytic syndrome (HPS) was suspected from hyper-ferritinemia, bone marrow aspiration was conducted. Macrophage confirmed hemophagocytic image and the patient was diagnosed with HPS complication. Methylprednisolone pulse therapy was conducted for three days, followed by the administration of prednisolone 60 mg. Plasma exchange therapy was also conducted from the first day of hospitalization. Recurrence of TTP after plasma exchange therapy, but it improved by additional plasma exchange. Low vWF-CP (ADAMTS-13) activity was observed in this case, and anti-vWF-CP antibody was positive. TTP and HPS are both critical intractable complications of SLE. Bearing in mind the possibility of simultaneous complication of both symptoms, prompt diagnosis is crucial for life-saving.

Adult↗

PubMed2006

[Case of traumatically bleeding shock patient rescued by using an aortic occlusion balloon catheter during surgery].

A 55-year-old (163 cm, 70 kg) man with traumatic intra-abdominal bleeding underwent emergency operation. The patient was in a state of hemorrhagic shock with 82 mmHg of systolic blood pressure (SBP) at hospital arrival. His condition became severer within about 1 hr, and tracheal intubation and mechanical ventilation were consequently started in the ambulatory emergency room. SBP decreased to 60 mmHg when he was transferred to the operating room. Anesthesia was induced with intravenous fentanyl and vecuronium, and was maintained with inhalation of sevoflurane in 50% oxygen. After laparotomy, it was impossible to detect the bleeding source because of a large quantity of hemorrhage. To reduce the blood loss, aortic occlusion balloon catheter (AOBC) was inserted into the upper abdominal aorta via the right femoral artery. Aortic occlusion was performed twice each for twenty minutes. The evelation of SBP and decrease of bleeding dose were secured by aortic occlusion. Thereby the source of bleeding could be detected and surgical procedure could be finished with survival of the patient. The insertion of AOBC for the surgical patient with intra-abdominal hemorrhagic shock may be advantageous for uncontrollable bleeding.

Abdominal Injuries↗

PubMed2006

[Intensive psychiatric treatment system for bulimic patients by group therapy].

Concurrent bulimia nervosa/purging type and anorexia nervosa/binge-purging type including binge eating and purging behaviors are considered chronic types of eating disorders. The bulimic patients in this study had both these disorders. Psychiatric treatment for patients with eating disorders must focus on therapy of these bulimic patients, because bulimic patients are more prevalent in the psychiatric hospital and clinic, and they have more comorbid psychiatric disorders and more other addictive behaviors than other patients with eating disorders. We have devised an intensive psychiatric treatment system for bulimic patients by group therapy that consists of inpatient treatment, group therapy for parents and group rehabilitation. Inpatient treatment, called the Eating Disorders Education Program (EDEP), consists of group psychological education, group cognitive-behavioral therapy, group nutrition education, and group exercise. Group therapy for parents consists of psychological education and group meetings. Group rehabilitation consists of many group activities in a house named "Mimoza". Bulimic patients come to understand their own disorders and symptoms objectively and understand recovery from their disorders by the intensive treatment system. Bulimic patients generally recover very slowly from eating disorders, but our intensive psychiatric treatment system promotes rapid recovery.

Adolescent↗

PubMed2006

[Sudden death due to pulmonary tumor embolism from testicular tumor: a case report].

A 40-year-old man undergoing treatment for testicular tumor with para-aortic lymph node metastasis was transferred to our department because of pulmonary embolism. Thrombolysis therapy improved his respiratory state and deep venous thrombi disappeared. However, cardiopulmonary arrest occurred suddenly. Autopsy showed tumor cell invasion into the intima of the pulmonary artery and dissection with thrombosis. Thrombi had fresh components above organizing components. Sudden death due to pulmonary tumor embolism from testicular tumor is rare. In this case, the sudden death resulted from thrombosis in the pulmonary artery, not from emboli from the deep vein.

Adult↗

PubMed2005

IFN-inducible protein-10 plays a pivotal role in maintaining slit-diaphragm function by regulating podocyte cell-cycle balance.

IFN-inducible protein-10 (IP-10/CXCL10) is a potent chemoattractant for activated T lymphocytes and was reported recently to have several additional biologic activities. In this study, the pathophysiologic role of IP-10 in the glomerular visceral epithelial cell (podocyte) was investigated. In cultured podocytes subjected to recombinant IP-10 treatment, the expression of slit-diaphragm (SD) components nephrin and podocin clearly was heightened. Rats that had puromycin aminonucleoside nephropathy and anti-nephrin antibody-induced nephropathy and were subjected to anti-IP-10 function-blocking antibody (anti-IP-10 mAb) treatment displayed a decrease in the protein level of SD components, as well as exacerbated proteinuria. For exploration of the mechanisms of this process, the interaction between IP-10 and the cell-cycle regulatory proteins was investigated. Cultured podocytes subjected to recombinant IP-10 treatment displayed an increase in the protein level of p27(Kip1), whereas the levels of cyclins E and A decreased. The expression of IP-10 and SD components was heightened by the treatment of siRNA of cyclin A, whereas these expressions were lowered by the treatment of siRNA of p27(Kip1). Proteinuric rats subjected to anti-IP-10 mAb treatment displayed a heightened expression of cyclin A from the early phase of the disease, which indicates that the anti-IP-10 mAb treatment exacerbates podocyte injury by disturbing the cell-cycle balance. These results raise the possibility that IP-10 could become a novel therapeutic target in nephrotic syndrome and several diseases with altered cell-cycle balance.

Animals↗

PubMed2005

Groove-spanning behavior of lipid membranes on microfabricated silicon substrates.

We report on a spreading behavior of phospholipid membranes that arise from a lump of phospholipid (a lipid source) on topographically patterned substrates immersed in an aqueous solution. Microgrooves with well-defined shapes were prepared on Si111 surfaces by anisotropic etching in an alkaline solution. A spreading front that consists of membrane lobes and a single lipid bilayer was observed on the patterned silicon substrates by utilizing fluorescence interference contrast (FLIC) microscopy. FLIC images indicate that the membrane lobes span the microgrooves, while the underlying single lipid bilayer spread along the surface of the microgrooves. In fact, fluorescent polystyrene nanoparticles could be encapsulated in the microgrooves that were completely covered with the membrane lobes. The groove-spanning behavior of membrane lobes is discussed in terms of a balance between adhesion and bending energies of lipid bilayers.

Fluorescence↗

PubMed2005

Napthalimidobenzamide DB-51630: a novel DNA binding agent inducing p300 gene expression and exerting a potent anti-cancer activity.

Control of gene expression by small molecule compounds is a novel therapeutic strategy for cancer and usually it requires the presence of specific molecular recognition. The development of the compounds preferentially binding to the specific DNA sequence is one of the potential but very difficult approaches in this strategy. We designed and synthesized novel napthalimidobenzamide derivatives and analyzed their binding preferences to oligonucleotides by EtBr-displacement assay with DNA sequences, being essential fragments of the genes. To test whether these compounds modify the expression of specific genes, we analyzed the effect on the gene expression in AZ521 cells by differential display analysis using the compounds showing different characteristics in the recognition of specific DNA sequence. Among them, DB-51630, which showed approximately 350 times higher preferential binding to GC-repeats than to the AT and AA-repeating oligomers, caused the induction of a specific mRNA. The genetic sequence was identified to be the p300 gene by sequencing of the cloned cDNA. The p300 is a transcriptional co-activator protein that acts with other nuclear proteins in various cell differentiation and signal transduction pathways. This protein has intrinsic histone acetyltransferase activity and may act on chromatin directly to facilitate transcription. The increase of the amount of p300 mRNA increased after DB-51630 treatment by real time RT-PCR and Northern blot analysis. DB-51630 inhibited cell growth in various cancer cell lines at nanomolar range of concentrations, whereas p300 mRNA induction was observed at sub-nanomolar concentrations and the maximal induction occurred 8h after DB-51630 treatment. In contrast, anti-cancer drugs such as doxorubicin, vincristine, cisplatin, etoposide, and actinomycin D did not increase p300 transcription. DB-51630 revealed potent anti-cancer activity against human solid tumor xenografts. Thus, we demonstrated the anti-cancer activity of DB-51630, which interacts with a specific DNA sequence, thereby inducing p300 gene expression and exhibited significant anti-cancer activity in human tumor xenografts. Furthermore, such compounds that bind to specific DNA sequences may not only control the expression of specific genes but also exert other mechanisms in the anti-cancer effect than those of classical DNA binding drugs.

Antineoplastic Agents↗

PubMed2005

Novel and orally bioavailable inducible nitric oxide synthase inhibitors: synthesis and evaluation of optically active 4,5-dialkyl-2-iminoselenazolidine derivatives.

We have previously reported that (4R,5R)-5-ethyl-2-imino-4-methylthiazolidine (3) strongly inhibits inducible nitric oxide synthase (iNOS). In a successive search for strong and selective iNOS inhibitors, we, herein, describe the synthesis of the selenium analogue of 3 (4: ES-2133) and its related optically active compounds and examine their in vitro and in vivo inhibitory activity against iNOS. In addition, an alternative synthetic method to the selected compound 4 and its pharmacokinetic profile is also reported.

Arginine↗

PubMed2005

Syntheses and properties of the major hydroxy metabolites in humans of blonanserin AD-5423, a novel antipsychotic agent.

Two major metabolites in humans of blonanserin, 2-(4-ethyl-1-piperazinyl)-4-(4-fluorophenyl)-5,6,7,8,9,10-hexahydrocycloocta-[b]pyridine (code name AD-5423), were synthesized. The first, 7-hydroxylated AD-5423, was synthesized through a four-step process starting from 4-fluorobenzoylacetonitrile (1), and the second, 8-hydroxylated AD-5423, a nine-step process also from 1. The optical resolution, structures, and receptor binding properties of the metabolites were documented.

Antipsychotic Agents↗

PubMed2005

Characterization of the Arabidopsis thaliana mutant pcb2 which accumulates divinyl chlorophylls.

We characterized the pcb2 (pale-green and chlorophyll b reduced 2) mutant. We found through electron microscopic observation that chloroplasts of pcb2 mesophyll cells lacked distinctive grana stacks. High-performance liquid chromatography (HPLC) analysis showed that the pcb2 mutant accumulated divinyl chlorophylls, and the relative amount of divinyl chlorophyll b was remarkably less than that of divinyl chlorophyll a. The responsible gene was mapped in an area of 190 kb length at the upper arm of the 5th chromosome, and comparison of DNA sequences revealed a single nucleotide substitution causing a nonsense mutation in At5g18660. Complementation analysis confirmed that the wild-type of this gene suppressed the phenotypes of the mutation. Antisense transformants of the gene also accumulated divinyl chlorophylls. The genes homologous to At5g18660 are conserved in a broad range of species in the plant kingdom, and have similarity to reductases. Our results suggest that the PCB2 product is divinyl protochlorophyllide 8-vinyl reductase.

Arabidopsis↗

PubMed2005

Daily life activity and the risk of developing hypertension in middle-aged Japanese men.

BACKGROUND: Although previous studies suggest that physical activity may reduce the risk of hypertension, the role of daily life activity in the development of hypertension remains unclear. METHODS: The study population included 2548 Japanese male office workers aged 35 to 59 years, who were without hypertension (systolic blood pressure [SBP] <140 mm Hg, diastolic blood pressure [DBP] <90 mm Hg, and no medication for hypertension) and had no history of cardiovascular disease. Daily life energy expenditure was estimated by a 1-day activity record during an ordinary weekday at study entry. Blood pressures were measured at periodic annual health examinations over 7 successive years. RESULTS: After controlling for potential predictors of hypertension (age, family history of hypertension, alcohol consumption, cigarette smoking, regular physical exercise at entry, and change in body mass index during the follow-up period), mean SBP and DBP in each follow-up year decreased as daily life energy expenditure increased. With additional adjustment for SBP at entry, the relative risk of hypertension (SBP > or =140 mm Hg and/or DBP > or =90 mm Hg or medication for hypertension) across quartiles of daily life energy expenditure (lowest to highest) were 1.00, 0.84, 0.75, and 0.54 (P<.001 for trend). Analyses by presence or absence of a risk factor demonstrated that the risk of hypertension was inversely related to daily life energy expenditure in men at either low or high risk of hypertension. Daily life energy expenditure was also associated with reduced risk of hypertension for subjects in all 3 categories of normotension: low normal, normal, and high normal. CONCLUSIONS: Increased daily life activity is effective for the prevention of hypertension, and this benefit applies to men at either low or high risk of hypertension.

Adult↗

PubMed2005

Growth of giant membrane lobes mechanically driven by wetting fronts of phospholipid membranes at water-solid interfaces.

We report on the growth of giant membrane lobes that is mechanically driven by wetting fronts of phospholipid membranes at water-solid interfaces and a strategy to control the two-dimensional structure of the membrane lobes on a solid surface. The growth of giant membrane lobes was observed on a single-lipid bilayer which spread from a lump of phospholipid deposited on a silica-glass substrate or an oxidized silicon wafer in aqueous solutions of NaCl, KCl, MgCl2, or CaCl2 at relatively high salt concentrations. Most of the membrane lobes were very flat unilamellar tubes elongating from the lump of phospholipid, and their length reached 1 mm in 5 h. Experimental findings clearly indicate that the membrane lobes are adherent to the surface of the single-lipid bilayer and are mechanically elongated from the lump of phospholipid by the sliding motion of the single-lipid bilayer. We could control the two-dimensional structure of the membrane lobes on the substrate by controlling the spreading direction of the single-lipid bilayer using Pt micropatterns that were deposited on the smooth surface of the oxidized silicon wafer.

Lipid Bilayers↗

PubMed2005

Periodic measurement of serum carcinoembryonic antigen and carbohydrate antigen 15-3 levels as postoperative surveillance after breast cancer surgery.

PURPOSE: Breast cancer surveillance guidelines do not recommend routine tumor marker testing after surgery, despite which it is still widely performed in Japan. We investigated the clinical utility of postoperative tumor marker testing in a series of Japanese patients, in view of the fact that all the studies to date have been non-Japanese. METHODS: We retrospectively analyzed the lead time by periodic measurements of serum carcinoembryonic antigen (CEA) and carbohydrate antigen 15-3 (CA15-3) in 233 patients who underwent breast cancer surgery. Both tumor marker levels were measured every 3 months for the first 5 years, every 6 months for the next 5 years, then annually. Physical examination and chest X-ray were routinely done at the same time, and bone or computed tomographic scans were done if the tumor marker levels were elevated or clinical symptoms appeared. RESULTS: In patients with recurrent disease, the mean lead times were -333.9 days for CEA and -210.6 days for CA15-3, respectively. Elevated tumor marker levels were found much later than recurrence. CONCLUSION: Our results support the American Society of Clinical Oncology guidelines. Thus, the serial testing of tumor marker levels after breast cancer surgery may not be as beneficial as thought in Japan.

Adult↗

PubMed2005

Long-term survival after report resection of pulmonary metastases from hepatocellular carcinoma: report of two cases.

Hepatocellular carcinoma (HCC) is often treated most effectively by resection. Although improved surgical procedures and perioperative care have made hepatic resection safe, the prognosis of patients with HCC is still poor because of the high incidence of postoperative recurrence. The most common site of extrahepatic recurrence is the lung. However, because of its multiplicity and concurrent recurrence in the liver remnant, resection of pulmonary metastases form HCC is rarely beneficial. We report two cases of long-term survival after repeated pulmonary resection of metastasis from HCC. At the time of this report the two patients were free of disease, 110 months and 107 months, respectively, after their initial hepatectomy. These case reports show that pulmonary metastases from HCC can be successfully resected in selected patients.

Adult↗

PubMed2005

Antimicrobial activities of tosufloxacin against Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella branhamella catarrhalis isolated from otolaryngological infectious diseases.

In 2003, the Japan Society for Infectious Diseases in Otolaryngology conducted its third nationwide survey of clinical isolates from otolaryngological infectious diseases. We selected three primary causative organisms of otolaryngological infectious diseases, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella Branhamella catarrhalis, and evaluated their sensitivities to tosufloxacin (TFLX), a new oral quinolone, because the survey revealed a rise in drug-resistant strains, suggesting potential problems with the antibiotics commonly used against these organisms. The minimum inhibitory concentration (MIC)(90) values of TFLX against S. pneumoniae, H. influenzae, and M. catarrhalis were 0.25 microg/ml, <or=0.06 microg/ml, and <or=0.06 microg/ml respectively, and TFLX was shown to be as effective as or superior to other new quinolones. In addition, TFLX showed sufficient antimicrobial effects against frequently detected drug-resistant bacteria such as penicillin-resistant S. pneumoniae (PRSP) and beta-lactamase-negative, ampicillin-resistant strains of H. influenzae (BLNAR). Furthermore, only a few strains of bacteria showed resistance to TFLX.

Adolescent↗

PubMed2005

Rebamipide reduces indomethacin-induced gastric injury in mice via down-regulation of ICAM-1 expression.

Non-steroidal anti-inflammatory drugs (NSAIDs) induced gastric mucosal injury occurs through subsequent events following free radical production derived from activated neutrophils. In this study, we hypothesized that rebamipide, a novel anti-ulcer agent, exerts a protective effect on NSAID-induced gastric injury through its antioxidant properties. The protective effect of rebamipide in a mouse model of indomethacin-induced gastric injury and mechanisms for this effect were investigated. Pre-treatment with rebamipide significantly inhibited indomethacin-induced gastric mucosal injury in mice. Gastric thiobarbituric acid reactive substances (TBARS) levels and myeloperoxidase (MPO) activity substantially increased 3 hr after indomethacin administration. These increases were significantly inhibited by pre-treatment with rebamipide. Furthermore, rebamipide pre-treatment notably decreased intercellular adhesion molecule-1 (ICAM-1) expression that was up-regulated in gastric tissue treated with indomethacin. Therefore, rebamipide may reduce indomethacin-induced gastric mucosal injuries through its antioxidant effect, which inhibits the neutrophil activation step following up-regulation of ICAM-1 expression on endothelial cells.

Alanine↗

PubMed2005

False-positive reduction in computer-aided diagnostic scheme for detecting nodules in chest radiographs by means of massive training artificial neural network.

RATIONALE AND OBJECTIVE: We developed a technique that uses a multiple massive-training artificial neural network (multi-MTANN) to reduce the number of false-positive results in a computer-aided diagnostic (CAD) scheme for detecting nodules in chest radiographs. MATERIALS AND METHODS: Our database consisted of 91 solitary pulmonary nodules, including 64 malignant nodules and 27 benign nodules, in 91 chest radiographs. With our current CAD scheme based on a difference-image technique and linear discriminant analysis, we achieved a sensitivity of 82.4%, with 4.5 false positives per image. We developed the multi-MTANN for further reduction of the false positive rate. An MTANN is a highly nonlinear filter that can be trained with input images and corresponding teaching images. To reduce the effects of background levels in chest radiographs, we applied a background-trend-correction technique, followed by contrast normalization, to the input images for the MTANN. For enhancement of nodules, the teaching image was designed to contain the distribution for a "likelihood of being a nodule." Six MTANNs in the multi-MTANN were trained by using typical nodules and six different types of non-nodules (false positives). RESULTS: Use of the trained multi-MTANN eliminated 68.3% of false-positive findings with a reduction of one true-positive result. The false-positive rate of our original CAD scheme was improved from 4.5 to 1.4 false positives per image, at an overall sensitivity of 81.3%. CONCLUSION: Use of a multi-MTANN substantially reduced the false-positive rate of our CAD scheme for lung nodule detection on chest radiographs, while maintaining a level of sensitivity.

False Positive Reactions↗

PubMed2005

How can a massive training artificial neural network (MTANN) be trained with a small number of cases in the distinction between nodules and vessels in thoracic CT?

RATIONALE AND OBJECTIVES: To demonstrate that a massive training artificial neural network (MTANN) can be adequately trained with a small number of cases in the distinction between nodules and vessels (non-nodules) in thoracic computed tomography (CT) images. MATERIALS AND METHODS: An MTANN is a trainable, highly nonlinear filter consisting of a linear-output multilayer artificial neural network model. For enhancement of nodules and suppression of vessels, we used 10 nodules and 10 non-nodule images as training cases for MTANNs. The MTANN is trained with a large number of input subregions selected from the training cases and the corresponding pixels in teaching images that contain Gaussian distributions for nodules and zero for non-nodules. We trained three MTANNs with different numbers (1, 9, and 361) of training samples (pairs of the subregion and the teaching pixel) selected from the training cases. In order to investigate the basic characteristics of the trained MTANNs, we applied the MTANNs to simulated CT images containing various-sized model nodules (spheres) with different contrasts and various-sized model vessels (cylinders) with different orientations. In addition, we applied the trained MTANNs to nontraining actual clinical cases with 59 nodules and 1,726 non-nodules. RESULTS: In the output images for the simulated CT images by use of the MTANNs trained with small numbers (one and nine) of subregions, model vessels were clearly visible and were not removed; thus, the MTANNs were not trained properly. However, in the output image of the MTANN trained with a large number of subregions, various-sized model nodules with different contrasts were represented by light nodular distributions, whereas various-sized model vessels with different orientations were dark and thus were almost removed. This result indicates that the MTANN was able to learn, from a very small number of actual nodule and non-nodule cases, the distinction between nodules (spherelike objects) and vessels (cylinder-like objects). In nontraining clinical cases, the MTANN was able to distinguish actual nodules from actual vessels in CT images. For 59 actual nodules and 1,726 non-nodules, the performance of the MTANN decreased as the number of training samples (subregions) in each case decreased. CONCLUSIONS: The MTANN can be trained with a very small number of training cases (10 nodules and 10 non-nodules) in the distinction between nodules and non-nodules (vessels) in CT images. Massive training by scanning of training cases to produce a large number of training samples (input subregions and teaching pixels) would contributed to a high generalization ability of the MTANN.

Algorithms↗