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C Chen

Publications and source records attributed to C Chen.

At least 469 records · Page 26Linked to original sources
PubMed1999

Identification, purification and properties of a beta-1,3-glucan-specific lectin from the serum of the cockroach, Blaberus discoidalis which is implicated in immune defence reactions.

A lectin specific for laminarin, a beta-1,3-glucan, agglutinating baker's yeast and enhancing prophenoloxidase activation by laminarin, has been purified from the cockroach, Blaberus discoidalis, serum. Purification involved gel filtration with Bio-gel P300 and affinity chromatography on blue Sepharose CL-6B and laminarin-Sepharose 4B. The purified lectin has a molecular mass estimate of 520 kDa determined by gel filtration, and approximately 80 and 82 kDa by SDS-PAGE, under non-reducing and reducing conditions, respectively. After isoelectric focusing the lectin focused as a single band at pH 4.9. The purified lectin was stained by the periodic acid/Schiff's reagent showing that it is a glycoprotein, and was deglycosylated by endo-beta-N-acetylglu-cosaminidase F. Amino acid composition analysis showed the protein is similar to previously purified beta-1,3-glucan binding proteins from other invertebrates. In electron micrographs by negative staining, the protein formed large aggregates with 'Y'-shaped 'structural units' ca. 79 x 65 nm. Immunological tests confirmed that this lectin is not related to any other lectins previously purified from the same insect. This protein appears to be part of the hexamerin family of proteins. This is one of the first reports of a hexamerin-like molecule with lectin activity.

Agglutination Tests↗
PubMed1999

Synaptic and plasticity-associated proteins in anterior frontal cortex in severe mental illness.

Abnormalities of proteins involved in neurotransmission and neural plasticity at synapses are reported in schizophrenia, and may be markers of dysregulated neural connectivity in this illness. Studies of brain development and neural regeneration indicate a dynamic interplay between neural and oligodendroglial mechanisms in regulating synaptic plasticity and axonal sprouting. In the present study, markers of synapses (synaptophysin), plasticity (growth-associated protein-43) and oligodendrocytes (myelin basic protein) were investigated in anterior frontal cortex homogenates from individuals with schizophrenia and depression. Synaptophysin immunoreactivity was reduced in schizophrenics who died of natural causes relative to controls. Myelin basic protein immunoreactivity was decreased in both schizophrenics and depressed individuals who died by suicide. Overall, no changes were observed in growth-associated protein-43 immunoreactivity. However, a slight increase in immunoreactivity in depressed suicides relative to control was observed. These findings support the hypothesis that synaptic abnormalities are a substrate for disordered connectivity in severe mental illness, and suggest that synaptic-oligodendroglial interactions may contribute to the mechanism of dysregulation in certain cases.

Adult↗
PubMed1999

Blood pressure and the T174M and M235T polymorphisms of the angiotensinogen gene.

PURPOSE: The angiotensinogen gene (AGT), which encodes the precursor of the vasoactive hormone angiotensin II, has been reported to be associated with hypertension in Caucasian and Japanese populations. We examined the relationship between two common molecular variants of AGT, T174M and M235T and blood pressure in two cohorts from the Anqing region of China. Cohort I (N = 794) consisted of families ascertained by either hypertensive or hypotensive siblings; and Cohort II (N = 761) represented a collection of randomly selected families. METHODS: Blood pressure was measured according to standard protocols, and information on age, sex, body mass index, alcohol consumption, and cigarette smoking was collected by trained interviewers using standardized questionnaires. The association of AGT genotypes and blood pressure was examined in multivariate linear regression models, with adjustment for potential intrafamilial correlations. The respective T and M allele frequencies for T174M were 0.93 and 0.07, and 0.80 and 0.20 for M235T among the parents for randomly selected families. All the analyses were conducted after exclusion of individuals currently under antihypertensive medication. RESULTS: In the pooled analysis of the two cohorts, neither the T174M nor the M235T polymorphism was significantly associated with variations of blood pressure assuming a recessive (T174M: p = 0.73 and 0.61; M235T: p = 0.99 and 0.24; for SBP and DBP), dominant (T174M: p = 0.54 and 0.72; M235T: p = 0.79 and 0.12; for SBP and DBP), or additive (T174M: p = 0.52 and 0.67, M235T: p = 0.91 and 0.11; for SBP and DBP) model. Likewise, no statistically significant association was detected when the two cohorts were analyzed separately. The logistic regression analysis of hypertension also failed to reveal any association with these markers. CONCLUSIONS: In summary, our analyses suggest that the molecular variants of AGT may not be associated with variations of blood pressure in this rural Chinese population.

Adolescent↗
PubMed1999

Strain differences in bone density and calcium metabolism between C3H/HeJ and C57BL/6J mice.

Previous reports indicate that peak bone density is significantly higher in C3H/HeJ (C3H) than in C57BL/6J (C57BL) mice, making these two inbred strains useful models for studying the genetic basis for peak bone density. The following study was undertaken to examine whether strain differences in the bone density of C3H and C57BL mice are associated with differences in intestinal calcium (Ca) absorption. Calcium absorption was measured by the balance technique and animals received two injections of fluorochromes 5 days apart before killing. Subsequently, the femurs were removed and, following measurement of volumetric density, the left femur was divided into three equal parts and the middle third served as the femoral cortical diaphysis. Femur diaphyseal volumetric bone density, ash, and Ca content were 10%, 29%, and 29% higher in C3H than in C57BL mice (p < 0.001), respectively. Bone length, periosteal mineral apposition rate, and periosteal bone formation rate of femoral diaphyseal cortical bone were not significantly different between the two strains of mice, but the marrow area of C57BL mice was almost twofold that of C3H mice (p < 0.0001). Intestinal Ca absorption and 1,25-dihydroxyvitamin D [1,25(OH)2D]-stimulated Ca2+ uptake by intestinal mucosal cells were 38% and 51% higher in C3H than in C57BL mice p < 0.001), respectively. Serum Ca and 1,25(OH)2D levels were 6% and 32% higher in C3H than in C57BL mice (p < 0.001), respectively, and the number of intestinal-occupied vitamin D receptors was 51% higher in C3H than in C57BL mice (p < 0.01). In a second experiment, three groups of C3H mice and three groups of C57BL mice were fed diets that contained 0.4%, 0.1%, or 0.02% Ca, and serum Ca, 1,25(OH)2D, parathyroid hormone (PTH), and intestinal Ca absorption measured. At all dietary Ca levels, C3H mice maintained positive Ca absorption and absorbed significantly more Ca than C57BL mice. In contrast, at low dietary Ca levels (0.1% and 0.02% Ca), C57BL mice maintained negative Ca absorption. Low dietary Ca increased serum PTH significantly in C57BL but not in C3H mice, and decreased serum 1,25(OH)2D and Ca levels in both strains of mice. Our findings indicate that the C57BL mice relied more on the mobilization of Ca from bone to maintain extracellular Ca homeostasis than the C3H mice. We conclude that strain differences in bone mass and density between C3H and C57BL mice is expressed, in part, through the vitamin D and PTH endocrine systems and their effects on the maintenance of extracellular Ca homeostasis.

Animals↗
PubMed1999

Sequence requirement for hand-in-hand interaction in formation of RNA dimers and hexamers to gear phi29 DNA translocation motor.

Translocation of DNA or RNA is a ubiquitous phenomenon. One intricate translocation process is viral DNA packaging. During maturation, the lengthy genome of dsDNA viruses is translocated with remarkable velocity into a limited space within the procapsid. We have revealed that phi29 DNA packaging is accomplished by a mechanism similar to driving a bolt with a hex nut, which consists of six DNA-packaging pRNAs. Four bases in each of the two pRNA loops are involved in RNA/RNA interactions to form a hexagonal complex that gears the DNA translocating machine. Without considering the tertiary interaction, in some cases only two G/C pairs between the interacting loops could provide certain pRNAs with activity. When all four bases were paired, at least one G/C pair was required for DNA packaging. The maximum number of base pairings between the two loops to allow pRNA to retain wild-type activity was five, whereas the minimum number was five for one loop and three for the other. The findings were supported by phylogenetic analysis of seven pRNAs from different phages. A 75-base RNA segment, bases 23-97, was able to form dimer, to interlock into the hexamer, to compete with full-length pRNA for procapsid binding, and therefore to inhibit phi29 assembly in vitro. Our result suggests that segment 23-97 is a self-folded, independent domain involved in procapsid binding and RNA/RNA interaction in dimer and hexamer formation, whereas bases 1-22 and 98-120 are involved in DNA translocation but dispensable for RNA/RNA interaction. Therefore, this 75-base RNA could be a model for structural studies in RNA dimerization.

Bacillus Phages↗
PubMed1999

Expression of tobacco class II catalase gene activates the endogenous homologous gene and is associated with disease resistance in transgenic potato plants.

We have previously shown that healthy potato plants respond poorly to salicylic acid (SA) for activating disease resistance against the late blight fungal pathogen Phytophthora infestans. However, SA is essential for the establishment of potato systemic acquired resistance (SAR) against P. infestans after treatment with the fungal elicitor arachidonic acid (AA). To understand the molecular mechanisms through which AA induces SA-dependent SAR in potato, we have recently studied the expression of potato class II catalase (Cat2St) in comparison with its tobacco homologue, Cat2Nt, which has previously been shown to bind SA. In the present study, we show that tobacco Cat2Nt is expressed at high levels and accounts for almost half of total SA-binding activity detected in tobacco leaves. In contrast, potato Cat2St is not expressed in healthy leaves, which is associated with the low SA responsiveness of potato plants for activation of disease resistance mechanisms. Upon treatment with AA, expression of potato Cat2St is induced not only in AA-treated leaves, but also in the upper untreated parts of the plants, concomitant with the establishment of SA-dependent SAR to P. infestans. Moreover, expression of the tobacco Cat2Nt gene in transgenic potato plants leads to constitutive expression of the endogenous potato Cat2St gene and is associated with enhanced resistance to P. infestans. These results collectively indicate that plant SA-binding class II catalases may play an important role in the development of disease resistance, possibly by serving as biological targets of SA.

Catalase↗
PubMed1999

Anaerobic transformation of 1,1,1-trichloroethane by municipal digester sludge.

Anaerobic transformations of 1,1,1-trichloroethane (TCA), 1,1-dichloroethane (DCA), and chloroethane (CA) were studied with sludge from a lab-scale, municipal wastewater sludge digester. TCA was biologically transformed to DCA and CA and further to ethane by reductive dechlorination. TCA was also converted to acetic acid and 1,1-dichloroethene (11DCE) by cell-free extract. 11DCE was further biologically converted to ethene. This pathway was confirmed by transformation tests of TCA, DCA and CA, by tests with cell-free extract, and by chloride release during TCA degradation. With cell-free extract, acetic acid accounted for approximately 90% of the TCA transformed; tests with live cells indicate that the fraction of TCA transformed by this pathway decreased with lower biomass. The dechlorination of DCA to CA and CA to ethane was not stoichiometric. A high rate of TCA removal was observed under the experimental conditions. The results indicate that removal of TCA in anaerobic digestion should be complete, but DCA and CA could persist in a normally operating digester.

Anaerobiosis↗
PubMed1999

Enhanced antinociception of the model opioid peptide [D-penicillamine] enkephalin by P-glycoprotein modulation.

PURPOSE: This study was conducted to examine the influence of P-glycoprotein (P-gp) modulation on the pharmacodynamics of the model opioid peptide DPDPE. METHODS: Mice (n = 5-7/group) were pretreated with a single oral dose of the P-gp inhibitor GF120918 (25 or 250 mg/kg) or vehicle. 3H-DPDPE (10 mg/kg) or saline was administered 2.5 hr after pretreatment. Antinociception was determined, and blood and brain tissue were obtained, 10 min after DPDPE administration. RESULTS: A significant difference (p < 0.001) in DPDPE-associated antinociception was observed among mice pretreated with a 25- (83 +/- 16% MPR) or 250- (95 +/- 5% MPR) mg/kg dose of GF120918 in comparison to mice pretreated with vehicle (24 +/- 14% MPR) or mice receiving GF120918 without DPDPE (12 +/- 8% MPR). A significant difference (p < 0.01) in brain tissue DPDPE concentration also was observed among treatment groups [25 +/- 6 ng/g (vehicle), 37 +/- 11 ng/g (25 mg/kg GF120918), 70 +/- 8 ng/g (250 mg/kg GF120918)]. In contrast, blood DPDPE concentrations were not statistically different between groups (678 +/- 66, 677 +/- 130, and 818 +/- 236 ng/ml for vehicle, GF120918 [25 mg/kg], and GF120918 [250 mg/kg], respectively). A single 100-mg/kg i.p. dose of (+)verapamil increased the brain:blood DPDPE concentration ratio by approximately 70% relative to saline-treated control mice (0.139 +/- 0.021 vs. 0.0814 +/- 0.0130, p < 0.01), a change in partitioning similar to that observed with the low dose of GF120918. These data provide further support for a P-gp-based mechanism of brain:blood DPDPE distribution. CONCLUSIONS: The present study demonstrates that GF120918 modulates blood-brain disposition and antinociception of DPDPE. Coadministration of a P-gp inhibitor with DPDPE may improve the pharmacologic activity of this opioid peptide.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1999

Gross chromosomal rearrangements in Saccharomyces cerevisiae replication and recombination defective mutants.

Cancer progression is often associated with the accumulation of gross chromosomal rearrangements (GCRs), such as translocations, deletion of a chromosome arm, interstitial deletions or inversions. In many instances, GCRs inactivate tumour-suppressor genes or generate novel fusion proteins that initiate carcinogenesis. The mechanism underlying GCR formation appears to involve interactions between DNA sequences of little or no homology. We previously demonstrated that mutations in the gene encoding the largest subunit of the Saccharomyces cerevisiae single-stranded DNA binding protein (RFA1) increase microhomology-mediated GCR formation. To further our understanding of GCR formation, we have developed a novel mutator assay in S. cerevisiae that allows specific detection of such events. In this assay, the rate of GCR formation was increased 600-5, 000-fold by mutations in RFA1, RAD27, MRE11, XRS2 and RAD50, but was minimally affected by mutations in RAD51, RAD54, RAD57, YKU70, YKU80, LIG4 and POL30. Genetic analysis of these mutants suggested that at least three distinct pathways can suppress GCRs: two that suppress microhomology-mediated GCRs (RFA1 and RAD27) and one that suppresses non-homology-mediated GCRs (RAD50/MRE11/XRS2).

Alleles↗
PubMed1999

Intensification of the stem cell transplant induction regimen results in increased treatment-related mortality without improved outcome in multiple myeloma.

Randomized trials conducted by the Intergroupe Française du Myelome (IFM) demonstrate that the use of high-dose chemotherapy (HDCT) and stem cell transplantation (SCT) improves event-free (EFS) and overall survival (OS) in younger patients with multiple myeloma (MM). Nevertheless, current HDCT regimens remain inadequate as all patients ultimately relapse following SCT. In an attempt to improve the OS of MM patients post-SCT we used an escalated HDCT regimen incorporating both intensified melphalan (160 mg/m2) and fractionated total body irradiation (12 Gy) to maximize the dose response of myeloma cells to these agents and included infusional etoposide 60 mg/kg in an attempt to eradicate clonal B cells potentially contributing to the myeloma clone. One hundred patients with MM received this intensified SCT regimen. The 100-day treatment-related mortality was 12% predominantly reflecting the development of interstitial pneumonitis (IP) in 28% of patients of whom 7/28 (25%) died. The predicted 5-year OS and EFS following the diagnosis of MM were 60% and 35%, respectively. The median OS from the time of transplant is 41 months and the median EFS is 28 months. More than two prior chemotherapy regimens, previous radiation therapy (RT) and the presence of an abnormal karyotype involving chromosomes 11 or 13 were significantly predictive of poor outcome. Interferon maintenance was not associated with improved outcome. Intensification of the HDCT regimen utilizing etoposide together with escalated melphalan and TBI increases morbidity and mortality without increasing OS beyond that reported with less toxic regimens.

Adult↗
PubMed1999

Involvement of p38 mitogen-activated protein kinase in lipopolysaccharide-induced iNOS and COX-2 expression in J774 macrophages.

Both the nitrite and prostaglandin E2 (PGE2) release caused by lipopolysaccharide (LPS) in J774 macrophages are inhibited by SB 203580, a specific p38 mitogen-activated protein kinase (MAPK) inhibitor, in a concentration-dependent manner. The 50% inhibitory concentration (IC50) for nitrite and PGE2 responses was 1 microm and 0.5 microm, respectively. Inhibition was marked following simultaneous treatment with SB 203580 and LPS, and was much reduced when SB 203580 was added 6 hr after LPS treatment. In parallel, LPS induction of inducible NO synthase (iNOS) and cyclo-oxygenase-2 (COX-2) proteins and their steady-state levels of mRNA were reduced by SB 203580. LPS activation of nuclear factor-kappa B (NF-kappaB), activator protein-1 (AP-1) and p38 MAPK was also inhibited by SB 203580. These results suggest a crucial role of p38 MAPK in regulation of the transcriptional level of endotoxin LPS-induced iNOS and COX-2 protein expression.

Animals↗
PubMed1999

Detection and characterization of a mannan-binding lectin from the mosquito, Anopheles stephensi (Liston).

Two lectins from the serum of the mosquito, Anopheles stephensi (Liston), with distinct characteristics, were detected by agglutination of various animal erythrocytes. The lectins were developmental stage-specific and/or sex-related. One adult female-specific lectin was identified as mannan-specific, and named mosquito mannan-binding lectin (MBL). MBL cross-reacted immunologically with antibodies against a previously characterized cockroach lectin, Blaberus discoidalis lectin (BDL1), and its activity was almost completely blocked by the antibodies. Mosquito MBL agglutinated erythrocytes from human, sheep, goat and rabbit, but not chicken or mouse, and agglutination was inhibited by mannan and nitrophenol-modified sugar derivatives, but not by simple sugars. Using affinity chromatography with immobilized mannan on Sepharose 6B, the mosquito MBL was partially purified. Purified mosquito MBL shared biochemical properties with BDL1, containing two subunits of molecular mass of 28 and 30 kDa under reducing conditions in SDS/PAGE. Its activity is dependent on Ca(2+), and it is stable at pH 7-9 and at temperatures less than 30 degrees C.

Age Factors↗
PubMed1999

Hyaluronan decreases peritoneal fluid absorption: effect of molecular weight and concentration of hyaluronan.

BACKGROUND: We have recently shown that the addition of hyaluronan to peritoneal dialysis solution could decrease the peritoneal fluid absorption rate, possibly through decreasing peritoneal tissue hydraulic conductivity. The physical-chemical properties of hyaluronan were found to be both molecular weight and concentration dependent. In this study, we investigated the effects of different molecular weight as well as different concentrations of hyaluronan on the peritoneal fluid kinetics. METHODS: A four-hour dwell study was performed in 48 male Sprague-Dawley rats (6 rats in each group) with 131I albumin (RISA) as an intraperitoneal volume marker. Each rat was intraperitoneally injected with 25 ml of 1.36% glucose dialysate alone (control) or with 0.01% hyaluronan (HA) with different molecular weights [85,000 (HA85K group), 280,000 (HA280K group), 500,000 (HA500K group), and 4,000,000 (HA4M group) molecular wt] or with a different concentrations of hyaluronan [(molecular wt 500,000); 0.01% (0.01% HA group), 0.05% (0.05% HA group), 0.1% (0.1% HA group), and 0.5% (0.5% HA group) hyaluronan]. RESULTS: The peritoneal fluid absorption rate (as assessed by the RISA elimination rate, KE) was significantly decreased in the HA500K and H4M groups as well as in all the different concentration groups (with molecular wt 500,000) as compared with the control group, resulting in significantly higher net fluid removal in these groups (except for the H4M group) as compared with the control group. In the 0.5% HA group (but not in the other hyaluronan groups), the direct lymphatic absorption (KEB) was also significantly decreased. The transcapillary ultrafiltration rate (Qu) was significantly lower in the HA4M group as compared with the control group but significantly higher in the 0.05% HA (and tended to be higher in the 0.1% HA group) as compared with the other groups. No difference in Qu was found between the 0.5% HA group as compared with the control group, despite a more marked decrease in KE in this group as compared with the H4M group. There were no significant differences in KE, Qu, and net fluid removal between the HA85K and HA280K groups and the control group. CONCLUSIONS: Our results suggest that (a) the addition of hyaluronan to dialysate could decrease peritoneal fluid absorption and thus increase the net ultrafiltration; this effect appears to be both size dependent and concentration dependent. (b) High molecular weight fraction of hyaluronan may also decrease the transcapillary Qu by decreasing tissue hydraulic conductivity. (c) A higher concentration of hyaluronan in dialysate resulted in a more marked decrease in peritoneal fluid absorption (absorption to peritoneal tissues as well as direct lymphatic absorption), possibly through both decreasing tissue hydraulic conductivity and increasing fluid viscosity. (d) Decreasing tissue hydraulic conductivity by adding a high concentration of hyaluronan to dialysate does not decrease the transcapillary ultrafiltration, possibly because the osmotic effect of hyaluronan may counterbalance the decrease in transcapillary ultrafiltration because of the decrease in tissue hydraulic conductivity.

Absorption↗
PubMed1999

Studies of mesenchymal cells from 1st trimester human placenta: expression of cytokeratin outside the trophoblast lineage.

A fibroblast cell strain that expressed cytokeratins 8 and 18 was isolated from explanted first trimester placenta. Its properties were consistent with an origin in the villous fibroblast-myofibroblast lineage, including expression of vimentin, smooth muscle alpha-actin and fibroblast surface protein. The cells grew rapidly in vitro, and exhibited tightly aligned bipolar morphology at confluence, absence of multi-nucleated cells, lack of secreted chorionic gonadotrophin, and absence of HLA G, placental alkaline phosphatase and pregnancy-specific beta-1 glycoprotein (SP1). On these criteria it was concluded they were not trophoblasts. On the basis of their morphology, cytokeratin expression and absence of CD34 and endoglin it was concluded they were not endothelial cells. They lacked desmin and smooth muscle myosin and so were not vascular smooth muscle cells. Further mesenchymal cell isolates were studied to determine the generality of these findings. Phenotypic heterogeneity was a consistent characteristic, but cytokeratin-positive cells were always present both in first trimester and term strains. Desmin was absent from almost all the cells isolated using the protocols employed, despite its occurrence in a significant subpopulation of cells in the villous stroma. Cytokeratins 8 and 18 can be observed in the stromal compartment of both first trimester and term placental villi. Cytokeratin has hitherto been regarded as a highly reliable marker for cells of the trophoblast lineage in vitro. These observations suggest that care should be taken in characterization of placental cell isolates; trophoblasts should be identified by the presence of cytokeratin 7 in preference to cytokeratin 8/18. The functional significance of cytokeratin expression in placental mesenchymal cells remains to be established.

Biomarkers↗
PubMed1999

Activation of heat shock transcription factor 1 to a DNA binding form during the G(1)phase of the cell cycle.

The heat shock transcription factor (HSF) genes encode proteins that bind to the heat shock elements (HSE) of stress-inducible genes. We have observed the induction of HSF1, the ubiquitous member of the HSF family from a latent cytoplasmic state to a form competent to bind HSE during early G(1)in HeLa cells in the absence of stress. The induction of DNA-binding HSF1 coincided with a burst in cellular protein synthesis in early G(1)and inhibition of this translational peak prevented the formation of DNA binding-activated HSF1. A potential role for HSF1 in cell cycle regulation was suggested by the finding that cell lines stably overexpressing HSF1 showed an increased proportion of G(1)cells relative to other cell cycle phases. However, in contrast to the effects of heat shock, entry into G(1)did not lead to HSF1 hyperphosphorylation or increased activity of a heat shock promoter-reporter gene and did not cause the induction of heat shock protein 70 expression. Thus HSF1, previously implicated in the heat shock response is activated to a DNA binding from in G(1)under non-stress conditions and may play a role in G(1)regulation that does not involve the transcription of heat shock genes.

Cycloheximide↗
PubMed1999

Effect of trypsin inhibitor on reflux oesophagitis after total gastrectomy in rats.

OBJECTIVE: To characterise alkaline reflux oesophagitis after total gastrectomy in rats from the standpoints of cell proliferation and apoptosis and from its macroscopic and microscopic findings, and to evaluate the preventive and curative effects of camostat mesilate, a trypsin inhibitor. DESIGN: Open laboratory study. SETTING: University hospital, Japan. ANIMALS: 70 male Wistar rats. INTERVENTIONS: Total gastrectomy with Billroth II anastomosis (n = 30) and with Roux-en-Y anastomosis (n = 30) were used to establish reflux oesophagitis. Camostat mesilate was given for prevention and cure. The remaining 10 animals had a sham operation. MAIN OUTCOME MEASURES: Trypsin activity of the oesophagus, macroscopic and microscopic findings, bromodeoxyuridine (BrdU) and apoptotic cell labelling indices. RESULTS: Reflux oesophagitis was more common and extensive after Billroth II than Roux-en Y anastomosis. The BrdU labelling index was increased in oesophagitis, while the apoptotic index did not change. Camostat mesilate was effective in both preventing and treating oesophagitis. CONCLUSION: Trypsin has an important role in the development of reflux oesophagitis after total gastrectomy.

Animals↗
PubMed1999

Different effects of the constituents of EGb761 on apoptosis in rat cerebellar granule cells induced by hydroxyl radicals.

The present study was conducted to evaluate the different effects of the constituents of EGb761 (Ginkgo biloba Extract) on apoptosis in cerebellar granule cells induced by hydroxyl radicals. The total flavonoid component of EGb761, two pure EGb761 components (rutin and quercetin), and a mixture of flavonoids and terpenes protected cerebellar granule cells from oxidative damage and apoptosis induced by hydroxyl radicals. ESR(electron spin resonance) results showed that the IC50 of the flavonoids for scavenging hydroxyl radicals was almost the same as that of EGb761, even though flavonoids make up only 24% of EGb761, implying that other constituents of EGb761 besides flavonoids can scavenge hydroxyl radicals. Total terpenes of EGb761 did not protect against apoptosis. Flavonoids and terpenes did not show a synergistic effect in this regard. Terpenes did not scavenge hydroxyl radicals directly, which might be related to their "cage-like" structures.

Animals↗