Biomedical subjects

Y Sakurai

Publications and source records attributed to Y Sakurai.

At least 91 records · Page 5Linked to original sources

PubMed2000

Performance of bent-crystal monochromators for high-energy synchrotron radiation.

Two monochromators for high-energy synchrotron radiation have been studied at the elliptical multipole wiggler beamline BL08W of SPring-8. Both monochromator crystals are bent and indirectly water-cooled. In the 100 keV monochromator an efficient cooling scheme is employed. A monochromatic beam is successfully focused using new benders for the 100 keV and 300 keV monochromators. Measured radii of curvature of the bent crystal agree qualitatively with calculation.

Journal Article↗

PubMed2000

Doxorubicin-loaded poly(ethylene glycol)-poly(beta-benzyl-L-aspartate) copolymer micelles: their pharmaceutical characteristics and biological significance.

Doxorubicin (DOX) was physically loaded into micelles prepared from poly(ethylene glycol)-poly(beta-benzyl-L-aspartate) block copolymer (PEG-PBLA) by an o/w emulsion method with a substantial drug loading level (15 to 20 w/w%). DOX-loaded micelles were narrowly distributed in size with diameters of approximately 50-70 nm. Dimer derivatives of DOX as well as DOX itself were revealed to be entrapped in the micelle, the former seems to improve micelle stability due to its low water solubility and possible interaction with benzyl residues of PBLA segments through pi-pi stacking. Release of DOX compounds from the micelles proceeded in two stages: an initial rapid release was followed by a stage of slow and long-lasting release of DOX. Acceleration of DOX release can be obtained by lowering the surrounding pH from 7.4 to 5.0, suggesting a pH-sensitive release of DOX from the micelles. A remarkable improvement in blood circulation of DOX was achieved by use of PEG-PBLA micelle as a carrier presumably due to the reduced reticuloendothelial system uptake of the micelles through a steric stabilization mechanism. Finally, DOX loaded in the micelle showed a considerably higher antitumor activity compared to free DOX against mouse C26 tumor by i.v. injection, indicating a promising feature for PEG-PBLA micelle as a long-circulating carrier system useful in modulated drug delivery.

Adenosarcoma↗

PubMed2000

Alteration of sensitivity of intratumor quiescent and total cells to gamma-rays following thermal neutron irradiation with or without 10B-compound.

PURPOSE: Changes in the sensitivity of intratumor quiescent (Q) and total cells to gamma-rays following thermal neutron irradiation with or without 10B-compound were examined. METHODS AND MATERIALS: 5-Bromo-2'-deoxyuridine (BrdU) was injected to SCC VII tumor-bearing mice intraperitoneally 10 times to label all the proliferating (P) tumor cells. As priming irradiation, thermal neutrons alone or thermal neutrons with 10B-labeled sodium borocaptate (BSH) or dl-p-boronophenylalanine (BPA) were administered. The tumor-bearing mice then received a series of gamma-ray radiation doses, 0 through 24 h after the priming irradiation. During this period, no BrdU was administered. Immediately after the second irradiation, the tumors were excised, minced, and trypsinized. Following incubation of tumor cells with cytokinesis blocker, the micronucleus (MN) frequency in cells without BrdU labeling (= Q cells at the time of priming irradiation) was determined using immunofluorescence staining for BrdU. The MN frequency in the total (P + Q) tumor cells was determined from the tumors that were not pretreated with BrdU before the priming irradiation. To determine the BrdU-labeled cell ratios in the tumors at the time of the second irradiation, each group also included mice that were continuously administered BrdU until just before the second irradiation using mini-osmotic pumps which had been implanted subcutaneously 5 days before the priming irradiation. RESULTS: In total cells, during the interval between the two irradiations, the tumor sensitivity to gamma-rays relative to that immediately after priming irradiation decreased with the priming irradiation ranking in the following order: thermal neutrons only > thermal neutrons with BSH > thermal neutrons with BPA. In contrast, in Q cells, during that time the sensitivity increased in the following order: thermal neutrons only < thermal neutrons with BSH < thermal neutrons with BPA. The longer the interval between the two irradiations, the higher was the BrdU-labeled cell ratio at the second irradiation. The labeled cell ratio at the same time point after each priming irradiation increased in the following order: thermal neutrons only < thermal neutrons with BSH < thermal neutrons with BPA. CONCLUSION: These findings indicated that the use of 10B-compound, especially BPA, in thermal neutron irradiation causes the recruitment from the Q to P population.

Animals↗

PubMed2000

3,4-dihydro-2(1H)-quinolinone as a novel antidepressant drug: synthesis and pharmacology of 1-[3-[4-(3-chlorophenyl)-1-piperazinyl]propyl]-3,4- dihydro-5-methoxy-2(1H)-quinolinone and its derivatives.

To develop a novel antidepressant drug with central nervous system-stimulating activity, we prepared a series of 1-[omega-(4-substituted phenyl-1-piperazinyl)alkyl]-3, 4-dihydro-2(1H)-quinolinone derivatives and examined their activities by their effects at 30 and 100 mg/kg po on the sleeping time of mice anesthetized with halothane and on the time required for recovery from coma induced in mice by cerebral concussion. We examined their binding affinities for sigma receptors by evaluating their ability to inhibit [(3)H]-1,3-di(o-tolyl)guanidine ([(3)H]DTG) binding to the rat whole brain membrane in comparison with three putative sigma receptor agonists: 1,3-di(o-tolyl)guanidine (DTG, 66), (+)-1,2,3,4,5,6-hexahydro-6,11-dimethyl-3-(2-propenyl)-2, 6-methano-3-benzazecin-8-ol (SKF10,047, 67), and (+)-1,2,3,4,5, 6-hexahydro-6,11-dimethyl-3-(3-methyl-2-butenyl)-2, 6-methano-3-benzazecin-8-ol (pentazocine, 68). Among the series of derivatives, 1-[3-[4-(3-chlorophenyl)-1-piperazinyl]propyl]-3, 4-dihydro-5-methoxy-2(1H)-quinolinone hydrochloride (34b) and its mesylate (34c), at a dose of 30 mg/kg po, reduced the sleeping time and the time for recovery from coma and they inhibited [(3)H]DTG binding for sigma receptors. The putative sigma receptor agonists reduced the sleeping time and the time for recovery from coma whereas two sigma receptor antagonists, alpha-(4-fluorophenyl)-4-(5-fluoro-2-pyrimidinyl)-1-piperazinebutanol hydrochloride (BMY14802, 69) and cis-9-[3-(3, 5-dimethyl-1-piperazinyl)propyl]carbazole dihydrochloride (rimcazole, 70), were inactive in the two tests. Preadministration of the putative sigma receptor antagonists 69 (3 mg/kg po) and 70 (30 mg/kg po) completely antagonized the actions of 34b and the sigma receptor agonists in the test for recovery from coma. These results suggested that 34b and 34c are sigma receptor agonists. Furthermore, a single administration of 1 and 10 mg/kg po 34b and 34c showed antidepressant-like activity by reducing the immobility time in the forced-swimming test with mice, while a tricyclic antidepressant, 10, 11-dihydro-N,N-dimethyl-5H-dibenz[b,f]azepine-5-propanamine hydrochloride (imipramine, 1) (10 and 30 mg/kg po), did not reduce the time after a single administration. 1 reduced the time after repeated administration of 30 mg/kg po once a day for 4 days. The structure-activity relationship of the series of compounds is also discussed.

Animals↗

PubMed2000

Rapid cell sheet detachment from poly(N-isopropylacrylamide)-grafted porous cell culture membranes.

Fabrication of functional tissue constructs using sandwiched layers of cultured cells could prove to be an attractive approach to tissue engineering. Rapid detachment of cultured cell sheets is a very important recovery method that permits facile manipulation of the sheet and prevents functional damage. To accelerate the required culture substrate hydrophilic and hydrophobic structural changes in response to culture temperature alteration, poly(N-isopropylacrylamide) (PIPAAm) was grafted onto porous culture membranes by electron beam irradiation. Analyses by attenuated total reflection-Fourier transform IR and electron spectroscopy for chemical analysis revealed that PIPAAm was successfully grafted to surfaces of porous membranes. Atomic force microscopy (AFM) results showed that PIPAAm-grafted membranes had smoother surfaces than ungrafted controls while retaining their porous structure. The mean roughness of PIPAAm-grafted and -ungrafted porous membrane surfaces determined by digital AFM autocalculation was 4.40 +/- 0.4 and 5.9 +/- 0.4 nm, respectively. Tissue culture polystyrene (TCPS) dishes grafted with PIPAAm were compared with PIPAAm-grafted porous membranes in cell sheet detachment experiments. Approximately 75 min was required to completely detach cell sheets from PIPAAm-grafted TCPS surfaces compared to only 30 min to detach cell sheets from PIPAAm-grafted porous membranes. With porous membranes, the water accesses the PIPAAm-grafted surface from underneath and peripheral to the attached cell sheet, resulting in rapid hydration of grafted PIPAAm molecules and detachment of the cell sheet. With TCPS PIPAAm-grafted surfaces the water is supplied from only the periphery of a cell sheet, slowing detachment.

Acrylic Resins↗

PubMed2000

Temperature-responsive culture dishes allow nonenzymatic harvest of differentiated Madin-Darby canine kidney (MDCK) cell sheets.

We have developed a temperature-responsive culture dish grafted with a poly(N-isopropylacrylamide) (PIPAAm). Various types of cells adhere, spread, and proliferate on the grafted dishes in the presence of serum at 37 degrees C. By reducing only temperature, these cells can be harvested noninvasively from the dishes according to rapid hydration of the grafted polymer. Because the harvest does not need enzymatic digestion, differentiated cell phenotypes are retained. In the present study, a renal epithelial cell line, Madin-Darby canine kidney (MDCK) cell, was cultured on the dishes, and cell behavior was examined. MDCK cells showed differentiated phenotypes such as dome formation during long-term culture, similar to on ungrafted dishes. After 1-week culture at 37 degrees C, trypsin digestion disrupted cell-cell junctions but failed to liberate cells from both ungrafted and grafted dishes. However, short-term incubation at 20 degrees C released confluent MDCK cells as a single contiguous cell sheet only from the polymer-grafted dishes because of selective disruption of the cell-surface binding. Immunocytochemistry with anti-beta-catenin antibody revealed that functional cell-cell junctions were organized even in the recovered cell sheets. Intriguingly, incubation time at 20 degrees C required for cell sheet detachment gradually shortened during long-term culture before reducing temperature. The acceleration of cell detachment was correlated to the decrease of a single cell area by means of cell contractile force. These findings suggest that cell sheet detachment from PIPAAm-grafted dishes should be accomplished by both PIPAAm hydration and cellular metabolic activity such as cell contraction.

Acrylic Resins↗

PubMed2000

Comparison of radiation effects of gadolinium and boron neutron capture reactions.

PURPOSE: Cell survival assays were performed to evaluate the effects of radiations released during neutron capture reactions by gadolinium-157, boron-10 and by the combination of both. MATERIALS AND METHODS: Single cell suspensions with or without Gd-157 and/or B-10 were exposed to thermal neutrons produced by the Kyoto University reactor, and standard cell survival curves were obtained. RESULTS: Under the same molarity, cytocidal effects were 1.5 times greater for Gd-157 than for boron when compared at 10% survival levels. The presence of B-10 enhanced the radiation effect of Gd-157 neutron capture by 1.2-fold, suggesting that cells were not sufficiently irradiated as a result of neutron fluency attenuation by the presence of excess neutron capture agents in the medium. CONCLUSIONS: When an equal number of atoms were present, Gd-157 was effective as B-10 when exposed to an equal number of thermal neutrons. However, there was no benefit observed in the combination of Gd-157 and B-10 for neutron capture therapy. Further studies are needed to determine optimal Gd-157 and B-10 concentrations as a function of tumor dimension.

Animals↗

PubMed2000

Assessment of in vivo glucose kinetics using stable isotope tracers to determine their alteration in humans during critical illness.

Glucose plays a central role in energy metabolism, and alterations in its utilization have been reported under a variety of physiological and pathological conditions. The extent and direction of its changes provide useful information to promote the understanding of pathophysiology. The regulation of in vivo glucose kinetics is important because it is closely linked to energy production and the control of amino acid and protein metabolism. Although alterations in glucose kinetics have been demonstrated in critically ill patients, the mechanisms responsible are not well understood. The measurement of glucose kinetics in humans using stable isotopic glucose tracers provides a better understanding of the responses to nutritional support in these patients. While tracer methods have been used to quantitatively measure in vivo kinetics in patients with a variety of critical illnesses as well as in normal volunteers during fasting and exercise in European countries and the United States, they have not received the same attention in Japan. Stable isotopic glucose tracers can be safely given to humans since they are themselves naturally occurring substances, accounting for a small percentage of the total, depending on the isotopic species. The intravenous administration of a glucose tracer allows quantitative assessment of in vivo glucose kinetics under a variety of conditions. This method has wide potential for obtaining kinetic data on all aspects of in vivo glucose metabolism, with major advantages for conducting metabolic studies in humans.

Amino Acids↗

PubMed2000

The development of an elevated lesion associated with colitis cystica profunda in the transverse colonic mucosa during the course of ulcerative colitis: report of a case.

We report the case of a 53-year-old man with a long history of ulcerative colitis in whom an elevated lesion in the epithelium of the affected transverse colon was initially diagnosed as a benign inflammatory polyp by endoscopic biopsies. After 4 years of follow-up, because the tumor had enlarged and villous components were endoscopically observed on the surface, a colonic resection was performed. The tumor was found to consist of hyperplastic colonic epithelium associated with multiple mucinous cysts lined with dysplastic colonic epithelial cells. Moreover, the mucinous cysts were primarily located beneath the submucosal layer and appeared to intrude into the muscularis propria of the colonic wall. This lesion had a unique pathological feature, presumably indicating neither benign inflammatory epithelium nor a neoplastic lesion of the colonic epithelium. Mucinous cysts lined with colonic epithelial components in the muscularis propria suggest a loss of normal integrity of the colonic wall. Areas of the epithelial cell lining of the mucinous cysts showed apparent structural and nuclear atypia and positive expression for p53, suggesting that this portion of the specimen was dysplastic epithelium. These pathological findings may indicate one longitudinal aspect of tumor development which could provide evidence of premalignant change or initial pathological features during the long-standing course of ulcerative colitis.

Colitis↗

PubMed2000

Hyperplastic polyp of the gallbladder in a child.

We report a case of hyperplastic polyp of the gallbladder in a 6-year-old girl, successfully treated by laparoscopic cholecyctectomy after a 2-year follow-up from the original diagnosis. On her first admission, serum amylase level was very high, so that congenital pancreaticobiliary maljunction (PBM) was suspected. Although it became clear afterwards that the high serum amylase level was derived from a mumps infection, the diagnosis of PBM was not excluded until intraoperative cholangiography was conducted. The tumor in the gallbladder had doubled in size in 2 years. It was not possible to obtain biopsy specimens for histological diagnosis, so the risk of the tumor being malignant could not be completely excluded until surgical resection had been carried out. In spite of the rapid tumor growth, no neoplastic features were seen in the tumor by histopathological examination of the resected specimen; thus, a diagnosis of a hyperplastic polyp of the gallbladder was made.

Child↗

PubMed2000

Submucosal dermoid cyst of the rectum: report of a case.

Despite the relatively common incidence of sacrococcygeal dermoids, rectal cysts are uncommon. We report the case of a submucosal dermoid cyst occurring in the rectum. A 30-year-old woman visited the Gynecology Department because of pregnancy. A pelvic tumor was accidentally found during the checkup after miscarriage. A barium enema showed an anterior shift of the rectum by the presence of the tumor. Computed tomography and magnetic resonance imaging revealed a tumor located posterior to the rectum occupying almost the entire pelvic cavity, and the tumor was resected. The tumor was located in the submucosal layer of the posterior rectal wall and was well circumscribed. The resected tumor was a cyst entirely covered with a fibrous and firm capsule, which was filled with an amorphous white creamy substance. The histological findings showed the cyst consisting of a keratinizing stratified squamous epithelium with sebaceous gland and hair follicles, which was compatible with benign cystic teratoma. Primary rectal teratoma is very rare and only 36 cases have been reported in the literature worldwide. Furthermore, while the majority of cases were polypoid-shaped dermoid cysts protruding into the rectal lumen, only 3 cases were submucosal dermoid cysts. Therefore, such cases are considered to be extremely rare.

Adult↗

PubMed2000

Metastasis to the forearm skeletal muscle from an adenocarcinoma of the colon: report of a case.

While the liver and lung are primary targets for distant metastasis from colorectal carcinoma, metastasis in other distant sites is rarely found. We report herein an unusual case of metastasis to the skeletal muscle of the right forearm from an adenocarcinoma of the transverse colon. A 60-year-old man was originally admitted to our hospital for surgical treatment of an intestinal obstruction caused by a transverse colon carcinoma. Transverse colon resection along with lymph node dissection was performed and no evidence of distant metastatic foci was found. Angiography-enhanced computed tomography scanning done 14 months after the first operation revealed multiple hepatic metastases which were resected. A metastasis was subsequently detected in the right extensor carpi ulnaris muscle 2 years after the primary resection, and a major part of the right extensor carpi ulnaris and the extensor digiti minimi muscle were resected, warranting a sufficient margin of 5 cm of normal tissue from the tumor. Reattachment of the residual muscles into the ulna was performed. Metastases to bone and/or soft tissues from colorectal carcinomas are extremely rare and to our knowledge, only eight other cases have been reported in the world literature. This low incidence may be related to the anatomical characteristics and/or the biochemical environment of the skeletal muscle, but it is also possible that the true incidence is underestimated. Recent improvements in interventional radiological procedures may facilitate a diagnosis of skeletal muscle metastasis being made more frequently.

Adenocarcinoma↗

PubMed2000

Duration of obesity and risk of non-insulin-dependent diabetes mellitus.

Although obesity is one of the major risk factors for diabetes mellitus, the association of the duration of obesity with glucose intolerance or insulin dysregulation has not yet been clarified. Thirteen articles were picked up from the MEDLINE database by using the four key-word phrases, "duration of obesity," "duration of overweight," "prolonged obesity," and "prolonged overweight." Although the definition of overweight was similar among the children-based studies (> = 20% or 2 SD over ideal weight), the cutoff point for adults ranged from 25.0 to 30.0 kg/m2 of body mass index. With regard to the definition of the duration of obesity, the articles were roughly divided into two groups, with some researchers bearing the definition on the number of years from the onset of overweight and some calculating using the person-years method. The prevalence or incidence of non-insulin-dependent diabetes mellitus (NIDDM) or impaired glucose tolerance (IGT) are probably associated with the duration of obesity. The effect of prolonged obesity on insulin dysregulation is still unclear.

Adult↗

PubMed2000

Treatment of murine angiosarcoma with etoposide, TNP-470 and prednisolone.

To develop effective therapies for angiosarcoma, we investigated the anti-tumor effects of etoposide (ETO), TNP-470 and prednisolone (PSL) using an established murine angiosarcoma cell line (ISOS-1). We examined the direct anti-tumor and anti-angiogenic effects of these drugs on ISOS-1 cells and normal murine microvascular endothelial cells (mECs) in vitro. Cell growth of ISOS-1 was inhibited significantly by ETO, moderately by TNP-470, and not at all by PSL (IC(50): 0.25 microg/ml, 10 microg/ml, >8000 microg/ml, respectively). One the other hand, cell growth of mECs was inhibited significantly by TNP-470, slightly by PSL, and negligibly by ETO (IC(50): 0.85 ng/ml, 0.7 microg/ml, 10 microg/ml, respectively). In an in vivo assay, tumor growth of ISOS-1 was significantly inhibited by more than 2.5 mg/kg of ETO dose-dependently, and by more than 30 mg/kg of TNP-470, and 100 mg/kg of PSL individually. Combination treatments of ETO+TNP-470 and TNP-470+PSL showed synergistic enhancement of inhibition (% control inhibition: ETO vs. TNP-470 vs. ETO+TNP-470: 55 versus 55 vs. 16%) (% control inhibition: TNP-470 vs. PSL vs. TNP-470+PSL: 41 vs. 86 vs. 21%). ETO+PSL combination treatment, however, failed to show significant enhancement of anti-tumor effects. In conclusion, our results indicated that TNP-470 may be a very effective drug for angiosarcoma treatment, especially in combination with ETO or PSL. We eagerly anticipate the use of TNP-470 in clinical treatment of angiosarcoma.

Angiogenesis Inhibitors↗

PubMed2000

Different cortical activity in reading of Kanji words, Kana words and Kana nonwords.

We report a positron emission tomography study on reading of Japanese Kanji (morphograms) words, Kana (phonograms) words and Kana nonwords using statistical parametric mapping. Activity was more pronounced in the lateral fusiform gyrus (Area 37) in Kanji, in contrast to the greater activation in the middle and inferior occipital gyri (Areas 18 and 19) and the deep perisylvian temporo-parietal area (Areas 40/22 and 22/21) in Kana, suggesting that Kanji and Kana are processed differently.

Adolescent↗

PubMed2000

Inhibitory effect of low-level laser irradiation on LPS-stimulated prostaglandin E2 production and cyclooxygenase-2 in human gingival fibroblasts.

It has been reported that lipopolysaccharide (LPS) from periodontal pathogens can penetrate gingival tissues and stimulate the production of prostaglandin E2 (PGE2), which is known as a potent stimulator of inflammation and bone resorption. Although biostimulatory effects of low-level laser irradiation such as anti-inflammatory results have been reported, the physiological mechanism is not yet clarified. The purpose of the present study was to determine the effect of laser irradiation on PGE2 production and cyclooxygenase (COX)-1 and COX-2 gene expression in LPS-challenged human gingival fibroblast (hGF) cells in vitro. hGF cells were prepared from healthy gingival tissues and challenged with LPS, and Ga-Al-As diode laser was irradiated to the hGF cells. The amount of PGE2 released in the culture medium was measured by radioimmunoassay, and mRNA levels were analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR). Irradiation with Ga-Al-As diode low-level laser significantly inhibited PGE2 production in a dose-dependent manner, which led to a reduction of COX-2 mRNA levels. In conclusion, low-level laser irradiation inhibited PGE2 by LPS in hGF cells through a reduction of COX-2 mRNA level. The findings suggest that low-level laser irradiation may be of therapeutic benefit against the aggravation of gingivitis and periodontitis by bacterial infection.

Analysis of Variance↗

PubMed2000

Health risks among Japanese men with moderate body mass index.

BACKGROUND: Despite the westernized lifestyle, most Japanese are not prominently obese. As their obesity may be obscured, we want to further explore central fat distribution and health risks among this population. METHODS: 2668 men (body mass index (BMI) 20- < 26.4 kg/m2) were identified from 3343 men (BMI 14.0-37.7, median of waist-to-height ratio (W/Ht) 0.50) who underwent routine health examinations. They were divided into four groups: (1) BMI 20- < 24, W/Ht < 0.50; (2) BMI 20- < 24, W/Ht > or = 0.50; (3) BMI 24- < 26.4, W/Ht < 0.50; and (4) BMI 24- < 26.4, W/Ht > or = 0.50. The metabolic risks and physical activities were compared. RESULTS: W/Ht > or = 0.50 comprised 35% of the subjects of BMI 20- < 24, 91% of BMI 24- < 26.4, only 1% of BMI < 20 and up to 99% of BMI > or = 26.4. After adjusting for age and smoking and with group 1 as the reference group, odds ratios (ORs) were significantly higher in both groups 2 and 4 for the risk of hypertension (1.42, 1.98), hyperglycaemia (1.49, 1.78), hypertriglyceridaemia (1.95, 2.56), low HDL cholesterol (1.87, 2.20), hyperuricaemia (2.00, 2.51) and fatty liver (2.57, 5.64) and additionally in group 4 for hypercholesterolaemia (1.35). ORs in group 3 were only significantly higher for risk of hypertension (1.86) and fatty liver (1.89). Significantly lower frequencies of regular physical activity were noted in the higher W/Ht groups (0.75, 0.47, 1.10, 0.52 days per week, from groups 1-4, respectively). CONCLUSIONS: Measurement of waist circumference may be a preliminary method for the survey of people at higher risk of lifestyle-related disorders in Japanese men, especially among those with moderate BMI.

Abdomen↗

PubMed2000

Matrix metalloproteinase expression in cultured human gastric wall fibroblasts--interactions with Helicobacter pylori isolated from patients with ulcers.

BACKGROUND: Matrix metalloproteinases (MMPs), enzymes capable of degrading collagens and other extracellular matrix components, have been implicated in gastric ulcer formation. However, the effect on MMP expression of Helicobacter pylori, also implicated in these lesions, has not been studied to our knowledge. AIM: To seek links between H. pylori and MMP expression likely to affect gastric ulcer formation. After fibroblasts from human gastric wall were cocultured with H. pylori. concentrations of MMP-1 and -2 in the medium were determined by enzyme-linked immunosorbent assays. RESULTS: Whereas MMP-1 was not detected in media from fibroblasts or H. pylori culture alone, MMP-1 was detected in cocultures (P<0.01). Similar amounts of MMP-2 were detected in medium from fibroblasts cultured alone and with H. pylori. No MMP-2 production by H. pylori cultured alone was detected. CONCLUSIONS: MMP-1 appears to be important in gastric ulcer pathogenesis, and MMP-1 induction by H. pylori may impede gastric ulcer healing.

Cells, Cultured↗