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Kentaro Kojima

Publications and source records attributed to Kentaro Kojima.

11 recordsLinked to original sources
PubMed2007

Polyclonality of Staphylococcus epidermidis residing on the healthy ocular surface.

Staphylococcus epidermidis is part of the normal bacterial flora on the ocular surface. The chromosomal DNA of bacterial isolates obtained from the conjunctival sac, upper and lower lid margins, and upper and lower Meibomian glands of healthy volunteers was subjected to SmaI digestion and PFGE to study the genetic diversity of the organisms. Multiple colonies were also examined of S. epidermidis derived from the conjunctival sac of the same subjects. Lastly, commensal bacteria were harvested from the ocular surfaces of four healthy subjects once a month for 6 months, and the genetic background of the S. epidermidis isolates was analysed. It was found that bacterial strains not only from different subjects but also from multiple ocular surface sites of the same subject exhibited different PFGE patterns. In five of 42 subjects multiple colonies of S. epidermidis were isolated from the conjunctival sac; three harboured multiple colonies with different PFGE patterns, and two manifested multiple colonies with identical PFGE patterns. S. epidermidis isolated from the conjunctival sac of the same subjects over a 6-month period exhibited varying PFGE patterns. The data demonstrate the polyclonality of S. epidermidis on the healthy ocular surface.

Conjunctiva↗
PubMed2006

Human corneal epithelial cells respond to ocular-pathogenic, but not to nonpathogenic-flagellin.

In this study, we investigated the expression of TLR5 in human corneal epithelial cells (CEC), and the functional outcome of TLR5 triggering by flagellins of pathogenic- and nonpathogenic bacteria. Flagellins derived from Pseudomonas aeruginosa, Salmonella typhimurium, Serratia marcescense or Bacillus subtilis were used. The TLR5 protein and TLR5 specific mRNA expression was evident on human CEC. In human corneal epithelium tissues, TLR5 protein was detected at the basal and wing cells of the tissues. Ocular pathogenic bacteria, namely P. aeruginosa and S. marcescense, derived flagellin induced the significantly increased level of gene activation and IL-6 and IL-8 production. In contrast, ocular nonpathogenic S. typhimurium- and B. subtilis-derived flagellin induced neither the gene activation nor the increased production of IL-6 and IL-8 in human CEC. Human CEC would respond only to flagellin derived of ocular pathogenic bacteria, but not to those derived of ocular nonpathogenic bacteria, to generate pro-inflammatory cytokines.

Bacterial Proteins↗
PubMed2005

Platelet-activating factor in human normal tears.

PURPOSE: To measure the concentrations of platelet-activating factor (PAF) and lyso-PAF in tears of human eyes. METHODS: Unilateral tear samples were collected from the conjunctival cul-de-sac of 12 healthy volunteers without any past histories of ocular surface diseases and 10 patients with allergic conjunctivitis (AC) by graduated disposable microcapillaries. C18:0-PAF, C18:0-lyso-PAF, C16:0-PAF, and C16:0-lyso-PAF levels were determined by liquid chromatography-tandem mass spectrometry (LC/MS/MS). RESULTS: The concentrations of C18:0-PAF, C18:0-lyso-PAF, C16:0-PAF, and C16:0-lyso-PAF in tears from healthy volunteers were 0.44 +/- 0.39, 51.7 +/- 63.4, 61.9 +/- 75.9, and 10.7 +/- 14.7 ng/ml, respectively. Higher, but not significantly different, concentrations of all the four kinds of PAF molecules were detected in tears from AC patients. Significant correlations were demonstrated between the concentrations of C18:0-PAF and C18:0-lyso-PAF (r = 0.906; p < 0.01 in normal healthy volunteers and r = 0.939; p < 0.01 in AC patients), and between those of C16:0-PAF and C16:0-lyso-PAF (r = 0.944; p < 0.01 in normal healthy volunteers and r = 0.806; p = 0.015 in AC patients). Moreover, C18:0-PAF concentrations correlated significantly with those of C16:0-PAF (r = 0.885; p < 0.01 in normal healthy volunteers and r = 0.927; p < 0.01 in AC patients), while C18:0-lyso-PAF concentrations correlated significantly with those of C16:0-lyso-PAF (r = 0.972; p < 0.01 in normal healthy volunteers and r = 0.891; p < 0.01 in AC patients). CONCLUSIONS: To our knowledge, this is the first report of the concentrations of different species of PAF (C18:0-PAF, C18:0-lyso-PAF, C16:0-PAF, and C16:0-lyso-PAF) in human tears.

Adult↗
PubMed2004

[Airway obstruction during one-lung ventilation using a bronchial blocker and a tracheostomy tube].

We describe our experience with a 60-year-old man who had severe airway obstruction during one-lung ventilation with the tracheostomy tube using a bronchial blocker. The blocker, deriving from Univent tube, was passed through the tracheostomy tube and placed in the right main bronchus. We checked that the blocker was in appropriate place with a bronchofiberscope and obtained good one-lung ventilation with the patient in the left lateral position. However, just after the start of operation, when the skin was incised, sever hypoxia and resultant bradycardia and hypotension occurred, probably because of not only malposition of blocker but also atelectasis in the upper lobe of the dependent lung by secretion.

Airway Obstruction↗
PubMed2003

Xenogeneic direct hemoperfusion using whole swine liver for liver failure in dogs.

BACKGROUND: We developed a new method of xenogeneic direct hemoperfusion of a bioartificial liver support system consisting of a leukocyte-adsorbent column, an immunoglobulin-adsorbent column, and the substitute unit for hepatic function. By this method, we performed xenogeneic direct hemoperfusion experiment using resected whole swine liver for treatment of a canine liver failure model, and compared the contribution of each adsorbent column both by blood analysis and from the histological point of view. MATERIALS AND METHODS: Canine liver failure model was produced by portocaval shunting and ligating the entire hepatoduodenal ligament. The xenogeneic direct hemoperfusion system was constructed using a roller pump, a leukocyte-adsorbent column, an immunoglobulin-adsorbent column, a combined device of oxygenator and warmer, the resected whole swine liver accommodated in a chamber, and a dissolved oxygen meter through which canine whole blood leaving the external jugular vein circulated in this order. RESULTS: Xenogeneic direct hemoperfusion was successfully performed for 3 h without hyperacute rejection occurring. Adequate ammonia detoxification and bile juice secretion were exhibited, and no findings of hepatocyte destruction by immunological cells and proteins were detected. Blood data showed that the immunoglobulin adsorbent were more effective than the leukocyte adsorbent in avoiding hyperacute rejection. This result indicates that hyperacute rejection has a closer relation to humoral immune responses, especially regarding removal of complements than to cellular immune responses. CONCLUSIONS: We successfully performed xenogeneic direct hemoperfusion of the whole swine liver without hyperacute rejection using our method.

Adsorption↗
PubMed2003

Development of a new extracorporeal whole-liver perfusion system.

We have developed a new extracorporeal whole-liver accommodation device in which a whole swine liver is placed in a physiological state by modeling the intraabdominal arrangement in the pig body, with the liver supported by a special inferior vena cava tube. Furthermore, we employed a diaphragm-type artificial heart in our system to produce pulsatile blood flow through the hepatic artery, which is considered to be indispensable to dilate peripheral vessels and supply oxygenated whole blood to the peripheral liver tissue. Beneficial effects were demonstrated in visual findings and bile juice secretion. The color of the liver surface in our system remained bright red, indicating that the liver vessels were well drained and free from congestion, and bile juice secretion was maintained at more than 10 ml/h throughout the perfusion period. Our system exhibited excellent ammonia removal and urea nitrogen synthesis, and serum aspartate aminotransferase levels showed no increase, indicating the absence of hepatocyte destruction. Histological findings showed that the liver could expand appropriately and was free from compression caused by its own weight. In conclusion, our original liver accommodation device enabled appropriate expansion of the whole liver and supplied adequate oxygenated blood to peripheral areas by means of a pulsatile pump.

Adsorption↗
PubMed2003

Treatment of uncomplicated gonococcal urethritis by double-dosing of 200 mg cefixime at a 6-h interval.

The efficacy of antimicrobial regimens for the treatment of uncomplicated gonococcal urethritis depends partially upon the period of time (therapeutic time) during which the drug concentration in the blood after the concentration peak is greater than four times the minimum inhibitory concentration for 90% of clinical isolates of Neisseria gonorrhoeae (MIC(90)). A therapeutic time of at least 10 h is suggested as an important determinant for elimination of 95% or more of the infection. In this study, therapeutic times for a single 400-mg dose of cefixime at various MIC(90)s were calculated, and pharmacokinetic profiles of double-dosing of 200 mg cefixime at various intervals were simulated. Subsequently, a dosing interval of 6 h was tested in 6 healthy Japanese men, and then 93 Japanese men with gonococcal urethritis were treated with a regimen of two 200-mg doses of cefixime given at a 6-h interval. For a single dose of 400 mg cefixime, therapeutic times were calculated to be 12.8, 9.1, 5.4, and 1.7 h for MIC(90)s of 0.06, 0.125, 0.25, and 0.5 microg/ml, respectively. In the simulation study of double-dosing of 200 mg cefixime at a 6-h interval, the therapeutic times for the MIC(90)s of < or =0.125 microg/ml were longer than 10 h. Of the 93 patients, 68 were evaluated for microbiological outcome, and N. gonorrhoeae was eradicated in 60 (88.2%). The MIC(90) of cefixime for the 61 isolates tested was 0.125 microg/ml. All strains with MICs of < or =0.06 microg/ml were eradicated, whereas 8 of 16 strains with MICs of > or =0.125 microg/ml persisted after treatment. This regimen would not be effective against infection by strains exhibiting cefixime MIC(90)s of > or =0.125 microg/ml. For such strains, a different regimen with a higher dose of cefixime would be required.

Anti-Bacterial Agents↗
PubMed2003

[Comparison of extrusion rate for two different design of punctal plugs].

PURPOSE: Punctal occlusion using a silicone plug is an effective treatment for severe tear-deficient dry eye. At present, plugs from two companies are available in Japan [Eagle plug(EP); Eagle Vision, Punctal plug(PP); FCI]. We compared the extrusion rate between EP and PP in our dry eye clinic. SUBJECTS AND METHODS: Subjects were 20 eyes of 18 patients for EP [5 eyes from 5 males, 15 eyes from 13 females, age: 58.1 +/- 17.5(mean +/- standard deviation)] and 76 eyes of 51 patients for PP (6 eyes from 5 males, 70 eyes from 46 females, age: 58.6 +/- 13.4), 62 eyes from 44 patients with Sjögren syndrome, 34 eyes from 25 patients with non-Sjögren syndrome with severe tear-deficient dry eye treated for the period of November 1996 to February 2002 in our dry eye clinic. We compared the extrusion rate for each plug and necessity of reinsertion of the plug. RESULTS: In the examination for EP, 72.2% plugs were extruded during the follow-up periods, and the average period(59 days) until the extrusion was significantly shorter than for PP(p < 0.0001). In the examination for PP, 55.9% were extruded, and the average period until the extrusion was 287 days. Significant improvement of corneal epithelial damage was seen with PP after insertion of the plug. For the PP, reinsertion of plugs was sometimes impossible, probably because of the granulation formed inside the canaliculus, while for EP, reinsertion of the plugs was possible for all cases. DISCUSSION: EP becomes extruded more easily than PP, and PP is seems for to form granulation more easily.

Dry Eye Syndromes↗
PubMed2002

Effects of medetomidine-midazolam, acepromazine-butorphanol, and midazolam-butorphanol on induction dose of thiopental and propofol and on cardiopulmonary changes in dogs.

OBJECTIVE: To evaluate dose-sparing effects of medetomidine-midazolam (MM), acepromazine-butorphanol (AB), and midazolam-butorphanol (MB) on the induction dose of thiopental and propofol and to examine cardiopulmonary changes in dogs. ANIMALS: 23 healthy Beagles. PROCEDURE: Dogs were administered MM, AB, MB, or physiologic saline (0.9% NaCI) solution (PS) IM, and anesthesia was induced with thiopental or propofol. Cardiopulmonary measurements were obtained before and after administration of medication and 0, 5, 10, and 15 minutes after endotracheal intubation. RESULTS: Induction doses were reduced significantly by preanesthetic administration of MM, AB, and MB (thiopental, 20, 45, and 46% after administration of PS; propofol, 42, 58, and 74% after administration of PS, respectively). Recovery time in dogs administered MM-thiopental or MM-propofol and AB-propofol were significantly prolonged, compared with recovery time in dogs administered PS-thiopental or PS-propofol. Relatively large cardiovascular changes were induced by administration of MM, which were sustained even after the induction of anesthesia. Administration of AB and MB induced cardiovascular changes during and immediately after endotracheal intubation that were significantly decreased by induction with thiopental or propofol. However, mild hypotension developed with AB-propofol. Apnea was observed in dogs administered MM during induction of anesthesia, but most respiratory variables did not change significantly. CONCLUSIONS AND CLINICAL RELEVANCE: Preanesthetic medication with MM greatly reduced the anesthesia induction dose of thiopental and propofol but caused noticeable cardiopulmonary changes. Preanesthetic medication with AB and MB moderately reduced the induction dose of thiopental and propofol and amelio rated cardiovascular changes induced by these anesthetics, although AB caused mild hypotension.

Acepromazine↗
PubMed2002

[Outcome of punctal plug occlusion therapy for severe dry eye syndrome].

PURPOSE: Punctal occlusion using a silicone plug is one way of treating tear-deficient dry eye and it has been reported to be effective. We studied the outcome of punctal plug occlusion therapy for severe dry eye syndrome at our dry eye clinic. SUBJECTS AND METHODS: Subjects were 76 eyes of 51 patients [6 eyes of 5 males, 70 eyes of 46 females, mean age: 58.6 +/- 13.4 (mean +/- standard deviation), 49 eyes of 30 patients with Sjögren's syndrome, 27 eyes of 21 patients without Sjögren's syndrome] with severe tear-deficient dry eye who underwent punctal occlusion using a silicone plug (Punctal plug, FCI Co. Ltd, France) during the period of Nov. 1996 to Mar. 2000 at our dry eye clinic. They were under observation for 632 +/- 405 days (mean +/- standard deviation). We studied if there is difference in tolerance between the sizes of punctal plug, compared epithelial damage before and after plug insertion, and studied relief in symptoms using self-assessment. RESULTS: In tolerance of punctal plugs, 55.9% of all plugs were lost during our follow up, but there was no difference in time to loss between the sizes. Epithelial damage was reduced (p < 0.001). Dryness was the most reduced symptom: 26 patients (79%) got better, and only epiphora was increased, with 12 patients (36%) complaining slightly. CONCLUSION: Punctal plug occlusion therapy for tear-deficient dry eye is conclusively very effective.

Dry Eye Syndromes↗