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Observation of WZγ Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2024; 132:021802. [PMID: 38277610 DOI: 10.1103/physrevlett.132.021802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 09/30/2023] [Accepted: 11/08/2023] [Indexed: 01/28/2024]
Abstract
This Letter reports the observation of WZγ production and a measurement of its cross section using 140.1±1.2 fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The WZγ production cross section, with both the W and Z bosons decaying leptonically, pp→WZγ→ℓ^{'}^{±}νℓ^{+}ℓ^{-}γ (ℓ^{(^{'})}=e, μ), is measured in a fiducial phase-space region defined such that the leptons and the photon have high transverse momentum and the photon is isolated. The cross section is found to be 2.01±0.30(stat)±0.16(syst) fb. The corresponding standard model predicted cross section calculated at next-to-leading order in perturbative quantum chromodynamics and at leading order in the electroweak coupling constant is 1.50±0.06 fb. The observed significance of the WZγ signal is 6.3σ, compared with an expected significance of 5.0σ.
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Search for Dark Photons in Rare Z Boson Decays with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2023; 131:251801. [PMID: 38181367 DOI: 10.1103/physrevlett.131.251801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 10/11/2023] [Indexed: 01/07/2024]
Abstract
A search for events with a dark photon produced in association with a dark Higgs boson via rare decays of the standard model Z boson is presented, using 139 fb^{-1} of sqrt[s]=13 TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider. The dark boson decays into a pair of dark photons, and at least two of the three dark photons must each decay into a pair of electrons or muons, resulting in at least two same-flavor opposite-charge lepton pairs in the final state. The data are found to be consistent with the background prediction, and upper limits are set on the dark photon's coupling to the dark Higgs boson times the kinetic mixing between the standard model photon and the dark photon, α_{D}ϵ^{2}, in the dark photon mass range of [5, 40] GeV except for the ϒ mass window [8.8, 11.1] GeV. This search explores new parameter space not previously excluded by other experiments.
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Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at sqrt[s_{NN}]=5.02 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2023; 131:172301. [PMID: 37955510 DOI: 10.1103/physrevlett.131.172301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 05/11/2023] [Accepted: 09/18/2023] [Indexed: 11/14/2023]
Abstract
This letter presents a measurement of the nuclear modification factor of large-radius jets in sqrt[s_{NN}]=5.02 TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72 nb^{-1} and 257 pb^{-1} of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-k_{t} algorithm using a radius parameter of R=1.0, by reclustering anti-k_{t} R=0.2 jets, and are measured over the transverse momentum (p_{T}) kinematic range of 158
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Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings. PHYSICAL REVIEW LETTERS 2023; 131:162301. [PMID: 37925689 DOI: 10.1103/physrevlett.131.162301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/18/2023] [Accepted: 08/09/2023] [Indexed: 11/07/2023]
Abstract
A key open question in the study of multiparticle production in high-energy pp collisions is the relationship between the "ridge"-i.e., the observed azimuthal correlations between particles in the underlying event that extend over all rapidities-and hard or semihard scattering processes. In particular, it is not known whether jets or their soft fragments are correlated with particles in the underlying event. To address this question, two-particle correlations are measured in pp collisions at sqrt[s]=13 TeV using data collected by the ATLAS experiment at the LHC, with an integrated luminosity of 15.8 pb^{-1}, in two different configurations. In the first case, charged particles associated with jets are excluded from the correlation analysis, while in the second case, correlations are measured between particles within jets and charged particles from the underlying event. Second-order flow coefficients, v_{2}, are presented as a function of event multiplicity and transverse momentum. These measurements show that excluding particles associated with jets does not affect the measured correlations. Moreover, particles associated with jets do not exhibit any significant azimuthal correlations with the underlying event, ruling out hard processes contributing to the ridge.
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Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2023; 131:151902. [PMID: 37897770 DOI: 10.1103/physrevlett.131.151902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/31/2023] [Accepted: 08/11/2023] [Indexed: 10/30/2023]
Abstract
A search is made for potential ccc[over ¯]c[over ¯] tetraquarks decaying into a pair of charmonium states in the four muon final state using proton-proton collision data at sqrt[s]=13 TeV, corresponding to an integrated luminosity of 140 fb^{-1} recorded by the ATLAS experiment at LHC. Two decay channels, J/ψ+J/ψ→4μ and J/ψ+ψ(2S)→4μ, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J/ψ channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J/ψ+ψ(2S) channel. The fitted masses and decay widths of the structures are reported.
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Test of CP Invariance in Higgs Boson Vector-Boson-Fusion Production Using the H→γγ Channel with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2023; 131:061802. [PMID: 37625052 DOI: 10.1103/physrevlett.131.061802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 02/03/2023] [Indexed: 08/27/2023]
Abstract
A test of CP invariance in Higgs boson production via vector-boson fusion has been performed in the H→γγ channel using 139 fb^{-1} of proton-proton collision data at sqrt[s]=13 TeV collected by the ATLAS detector at the LHC. The optimal observable method is used to probe the CP structure of interactions between the Higgs boson and electroweak gauge bosons, as described by an effective field theory. No sign of CP violation is observed in the data. Constraints are set on the parameters describing the strength of the CP-odd component in the coupling between the Higgs boson and the electroweak gauge bosons in two effective field theory bases: d[over ˜] in the HISZ basis and c_{HW[over ˜]} in the Warsaw basis. The results presented are the most stringent constraints on CP violation in the coupling between Higgs and weak bosons. The 95% C.L. constraint on d[over ˜] is derived for the first time and the 95% C.L. constraint on c_{HW[over ˜]} has been improved by a factor of 5 compared to the previous measurement.
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Effects of General Anesthesia on Ocular Refraction. J Binocul Vis Ocul Motil 2022; 72:176-182. [PMID: 35763264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
PURPOSE General anesthesia alters the autonomic nervous system. This study aimed to investigate the effects of general anesthesia on objective ocular refraction. METHODS A total of 57 patients (112 eyes) under 15 years of age who underwent strabismus surgery under general anesthesia were included in this study. Objective refraction values, corneal refraction values, and pupil diameter were measured using a HandyRef-K, a hand-held refractive keratometer, in the operating room before and during general anesthesia before strabismus surgery. RESULTS The spherical power of the myopic eye increased from -0.75 D to -2.29 D (diopter); the cylindrical power increased from -0.90 D to -1.39 D (p < .01 for all). The corneal refractive power decreased by an average of 0.25 D (p < .01). The spherical refractive power was negatively correlated with the age and the amount of change between cycloplegia before general anesthesia and during general anesthesia (r = -0.32, p < .05). CONCLUSIONS General anesthesia resulted in manifestation of myopia as noted by the objective refraction values. Corneal refractive values flatten under the same conditions, suggesting that the contraction of the ciliary muscles was the main cause of myopia. We speculate that this change was due to parasympathetic dominance and contraction of the ciliary muscles during general anesthesia.
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NI-19 A case of Leber’s hereditary optic neuropathy with diffuse white matter changes mimicking gliomatosis cerebri. Neurooncol Adv 2021. [PMCID: PMC8648173 DOI: 10.1093/noajnl/vdab159.080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND: Leber’s hereditary optic neuropathy (LHON) is a mitochondrial disease characterized by bilateral severe subacute central vision loss and a mutation in the mitochondrial DNA (mtDNA). The cranial magnetic resonance imaging (MRI) of LHON patients varies from subtle to multiple white matter changes. However, they rarely present with diffuse infiltrative white matter changes. CASE REPORT: We report a case with diffuse white matter changes mimicking gliomatosis cerebri (GC). The histological findings included only mild glial hyperplasia without immunohistochemical positivity supporting the diagnosis of glial tumors. Analysis of mtDNA obtained from the blood and brain tissue revealed mutation of m.11778G>A in the NADH dehydrogenase 4 gene, which confirmed the case as LHON. Immunohistochemistry of the brain tissue revealed 8-hydroxy-2’-deoxyguanosine positivity, suggesting the presence of oxidative stress. CONCLUSION: LHON is extremely difficult to diagnose unless we suspect or know the disease. The present case brings attention not only to LHON but other mtDNA mutated diseases that need to be considered with diffuse white matter changes or GC.
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Leber’s hereditary optic neuropathy with diffuse white matter changes mimicking gliomatosis cerebri: illustrative case. JOURNAL OF NEUROSURGERY: CASE LESSONS 2021; 1:CASE21161. [PMID: 35854899 PMCID: PMC9245756 DOI: 10.3171/case21161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 05/12/2021] [Indexed: 11/06/2022]
Abstract
BACKGROUIND
Leber’s hereditary optic neuropathy (LHON) is a mitochondrial disease characterized by bilateral severe subacute central vision loss and a mutation in the mitochondrial DNA (mtDNA). The findings on cranial magnetic resonance imaging of patients with LHON vary from subtle to multiple white matter changes. However, they rarely present with diffuse infiltrative white matter changes.
OBSERVATIONS
The authors reported a case with diffuse white matter changes mimicking gliomatosis cerebri (GC). The histological findings included only mild glial hyperplasia without immunohistochemical positivity, supporting the diagnosis of glial tumors. Analysis of mtDNA obtained from the blood and brain tissue revealed mutation of m.11778G>A in the NADH dehydrogenase 4 gene, which confirmed the case as LHON. Immunohistochemistry of the brain tissue revealed 8-hydroxy-2′-deoxyguanosine positivity, suggesting the presence of oxidative stress.
LESSONS
LHON is extremely difficult to diagnose unless one suspects or knows the disease. The present case brings attention not only to LHON but also to other mtDNA-mutated diseases that need to be considered with diffuse white matter changes or GC.
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Interlaboratory Evaluation of Two Enzyme-Linked Immunosorbent Assay Kits for the Determination of Crustacean Protein in Processed Foods. J AOAC Int 2019. [DOI: 10.1093/jaoac/91.1.123] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
The labeling of foods containing material derived from crustaceans such as shrimp and crab is to become mandatory in Japan because of increases in the number of allergy patients. To ensure proper labeling, 2 novel sandwich enzyme-linked immunosorbent assay (ELISA) kits for the determination of crustacean protein in processed foods, the N kit (Nissui Pharmaceutical Co., Ltd, Ibaraki, Japan) and the M kit (Maruha Nichiro Holdings, Inc., Ibaraki, Japan), have been developed. Five types of model processed foods containing 10 and/or 11.9 g/g crustacean soluble protein were prepared for interlaboratory evaluation of the performance of these kits. The N kit displayed a relatively high level of reproducibility relative standard deviation (interlaboratory precision; 4.08.4 RSDR) and sufficient recovery (6586) for all the model processed foods. The M kit displayed sufficient reproducibility (17.620.5 RSDR) and a reasonably high level of recovery (82103). The repeatability relative standard deviation (RSDr) values regarding the detection of crustacean proteins in the 5 model foods were mostly <5.1 RSDr for the N kit and 9.9 RSDr for the M kit. In conclusion, the results of this interlaboratory evaluation suggest that both these ELISA kits would be very useful for detecting crustacean protein in processed foods.
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Childhood dietary intake: Comparison between anorexia nervosa and healthy leanness. Pediatr Int 2019; 61:73-79. [PMID: 30402965 DOI: 10.1111/ped.13730] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 07/23/2018] [Accepted: 10/01/2018] [Indexed: 11/30/2022]
Abstract
BACKGROUND The number of adolescent patients with anorexia nervosa is increasing. In addition, an increase in pre-adolescent patients with premenarchal onset has also been recognized. Detection of the disease in childhood and adolescence, however, is not always easy because the symptoms are not characteristic during this period. This study was performed to investigate detection of anorexia nervosa in children/adolescents by comparing energy and nutrient intake between patients with anorexia nervosa and healthy thin persons. METHODS The subjects consisted of 13 girls aged 14.4 ± 3.5 years with anorexia nervosa and 320 healthy girls aged 12.4 ± 1.3 years. Dietary intake was evaluated using a validated diet history questionnaire designed for children/adolescents. Daily energy and nutrient intake were expressed as a percentage of the age- and sex-matched reference amount. RESULTS Healthy lean (body mass index [BMI], <50th percentile) girls with an above-average score for desiring thinness had higher fat and lower cereal intake, and a trend of lower carbohydrate intake. In contrast, patients with anorexia nervosa, compared with thin (BMI <5th percentile) girls, characteristically had significantly lower energy, fat, zinc, vitamin C, and confectionery intake. CONCLUSIONS Lean girls with an above-average desire for thinness appear to restrict their energy intake by reducing their intake of carbohydrates such as cereals while maintaining a relatively high fat intake. In contrast, girls with anorexia nervosa avoided fat and had a preference for vegetables. This characteristic eating pattern could be a useful clue for detection of anorexia nervosa in thin children and adolescents.
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Qualitative Analysis of the Psychosocial Adaptation Process in Children with Chronic Kidney Disease: Toward Effective Support During Transition from Childhood to Adulthood. Yonago Acta Med 2018. [PMID: 30275747 DOI: 10.33160/yam.2018.09.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Background Pediatric chronic renal disease only shows abnormal values in a urinalysis in the initial stage, and subjective signs and symptoms are rare. If adolescents with chronic renal disease face a disease crisis combined with the usual developmental crisis, this may cause psychosocial maladaptation. We analyzed psychosocial adaptation in Japanese children with chronic renal disease in order to identify factors influencing healthy adaptation. Methods Ten children and adult patients with chronic kidney disease attending Tottori University Hospital, Japan in 2016 participated in a semi-structured interview (a modified version of the grounded theory approach) comprising questions about episodes since disease onset and thoughts/feelings at onset. Results Twenty-four concepts extracted from the data were sorted into 5 categories. These concepts and categories were expanded on an orthogonal axis with time and self-esteem in order to establish an adaptation model for children with chronic kidney disease. Category names are as follows. (Cat. 1: Emotional impact on being informed of disease, Cat. 2: Social challenges of treatment and resulting identity diffusion, Cat. 3: Emotional conflict on school return, Cat. 4: Resilience and related factors, Cat. 5: Re-establishment of identity). Conclusion Since pediatric chronic renal disease has few manifestations, it is difficult for patients to accept. Children facing a chronic disease crisis plus adolescent developmental crisis may show identity diffusion. In order for children to re-establish their identity and adapt to society, factors supporting resilience are important. Key factors include school life, interactions with friends, counseling by adult mentors and family acceptance. Healthcare professionals need to provide age-appropriate information on renal disease and support patients.
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A Rare Case of Huge Ovarian Teratoma Mimicking Omental Cyst Treated with Laparoscopic Surgery. J Minim Invasive Gynecol 2009. [DOI: 10.1016/j.jmig.2009.08.311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Analysis of soluble vascular endothelial growth factor receptor-1 secreted from cultured corneal and oral mucosal epithelial cell sheets in vitro. Br J Ophthalmol 2009; 93:263-7. [PMID: 19174402 DOI: 10.1136/bjo.2008.141580] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND In clinical trials, eyes transplanted with cultured oral mucosal epithelial cell sheets have shown increased neovascularisation compared with eyes treated with cultured corneal epithelial cell sheets. As reported recently, soluble vascular endothelial growth factor receptor-1 (soluble VEGFr-1) is a main factor to maintain a corneal avascularity. AIM To investigate soluble VEGFr-1 of cultured corneal epithelial cells (CCE) and cultured oral mucosal epithelial cells (COE) in vitro. METHODS Rabbit corneal and oral mucosal epithelial cells were co-cultured with mitomycin C-treated NIH/3T3 cells on culture plates. After CCE and COE were multilayered, culture medium was replaced by basal medium and incubated. Protein secretion of soluble VEGFr-1 was assessed in conditioned medium from CCE and COE by ELISA. Angiogenic potential was examined by invasion, migration assays with human umbilical vein endothelial cells (HUVECs) in addition to recombinant soluble VEGFr-1. RESULTS CCE secreted a significantly higher amount of soluble VEGFr-1 than did COE. Recombinant soluble VEGFr-1 significantly suppressed HUVEC migration induced by COE, without suppression in CCE. In conclusion, these findings suggest that low protein levels of soluble VEGFr-1 may lead to corneal neovascularisation after COE sheet transplantation.
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Serum CA125 level before the development of ovarian cancer. Int J Gynaecol Obstet 2007; 99:95-9. [PMID: 17643440 DOI: 10.1016/j.ijgo.2007.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Revised: 05/31/2007] [Accepted: 06/04/2007] [Indexed: 10/23/2022]
Abstract
BACKGROUND Little is known about the natural history of ovarian cancer with respect to the change of serum CA125 level. METHODS The Shizuoka Cohort Study on Ovarian Cancer Screening (SCSOCS) Trial contains approximately 100,000 data on serum tumor marker CA125 prospectively obtained from more than 70,000 women. We reviewed the clinical charts and collected serum samples 2 months to 9.4 years prior to the surgery were available. RESULTS In 396 (95%) of the 419 patients with ovarian cancer, one serum sample was present before the diagnosis (mean, 4.1 years). The change of CA125 level before the diagnosis of ovarian cancer could be clearly separated into two groups according to the length of the following intervals: 47% (107/228) of patients with non-serous-type ovarian cancers develop secondarily from slightly elevated CA125 level (35 <CA125 <65 U/ml), with a mean interval of 3.8 years. On the other hand, 75% (126/168) of patients with serous-type ovarian cancer seem to develop suddenly from a normal CA125 level (CA125 <35 U/ml), with a mean interval of 1.4 years (p=0.011). CONCLUSIONS The slightly elevated CA125 level is typically present many years before the diagnosis especially in patients with non-serous-type ovarian cancer. However, serous-type ovarian cancer may exhibit a rapid progression possibly through de novo carcinogenesis.
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Abstract
The purpose of this study was to determine whether Akt and mammalian target of rapamycin (mTOR), downstream targets of phosphatidylinositol 3-kinase, are activated in endometriosis and ovarian cancer specimens. We measured total and phosphorylated levels of Akt and mTOR from 17 frozen ovarian cancers and 15 benign endometriosis specimens (nine from premenopausal women and six from postmenopausal women) by quantitation of signals from western blots using antibodies against these proteins. Elevated phospho-Akt was detected in ovarian cancer versus endometriosis specimens from premenopausal women and endometriosis specimens from postmenopausal women (2.3 +/- 0.45 versus 0.10 +/- 0.06 and 0.17 +/- 0.11; P < 0.05) when the western blot signal of activated kinase was normalized to total kinase levels. Elevated phospho-mTOR was detected in ovarian cancer and postmenopausal endometriosis versus premenopausal endometriosis (0.52 +/- 0.19 and 0.46 +/- 0.29 versus 0.13 +/- 0.08; P < 0.05). Expression of total kinases (normalized to beta-actin) was higher in carcinoma versus endometriosis specimens. Elevation of the active mTOR was specifically detected in postmenopausal endometriosis.
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Analysis of gene expression in apoptosis of human lymphoma U937 cells induced by heat shock and the effects of α-phenyl N-tert-butylnitrone (PBN) and its derivatives. Apoptosis 2005; 10:331-40. [PMID: 15843894 DOI: 10.1007/s10495-005-0807-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Hyperthermia, a modality of cancer therapy, has been known as a stress to induce apoptosis. However, the molecular mechanism of heat shock-induced apoptosis, especially on roles of intracellular oxidative stress, is not fully understood. First, when human lymphoma U937 cells were treated with heat shock (44 degrees C, 30 min), the fraction of apoptosis, revealed by phosphatidylserine externalization, increased gradually and peaked at 6 hr after the treatment. In contrast, intracellular superoxide formation increased early during the heat shock treatment and peaked at 30 min after the treatment. When the cells were treated with heat shock in the presence of alpha -phenyl-N-tert-butylnitrone (PBN) and its derivatives, which are potent antioxidants, the DNA fragmentation was inhibited in an order according to the agents' hydrophobicity. PBN showing the highest inhibitory effects suppressed not only intracellular superoxide formation but also various apoptosis indicators. cDNA microarray was employed to analyze gene expression associated with heat shock-induced apoptosis, and the time-course microarray analysis revealed 5 groups showing changes in their pattern of gene expression. Among these genes, c-jun mRNA expression showed more than 40 fold increase 2 hr after heat treatment. The expression level of c-jun mRNA verified by quantitative real-time PCR was about 20 fold increase, and c-jun expression was similarly suppressed by PBN and its derivatives. These results suggest that the change of c-jun expression is an excellent molecular marker for apoptosis mediated by intracellular oxidative stress induced by heat shock.
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Dissipative structures formed in the course of drying the aqueous solution of n -dodecyltrimethylammonium chloride on a cover glass. Colloid Polym Sci 2004. [DOI: 10.1007/s00396-003-0972-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Electrostatic force theory for a molecule and interacting molecules. 7. Ab initio verification of the force concepts based on the flotating wave functions of ammonia, methyl(1+) ion, and ammonia(1+) ion. J Am Chem Soc 2002. [DOI: 10.1021/ja00492a015] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Phantom studies for estimation of defect size on cardiac (18)F SPECT and PET: implications for myocardial viability assessment. J Nucl Med 2001; 42:1579-85. [PMID: 11585876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
UNLABELLED SPECT with (18)F-FDG has emerged as an alternative to dedicated PET for the assessment of myocardial viability. However, whether FDG SPECT can reliably quantify the extent of viable and scarred myocardium is uncertain. The aim of this study was to investigate whether SPECT with an (18)F-labeled agent would provide information on defect size similar to that provided by dedicated PET. METHODS Imaging was performed using an elliptic cylinder chest phantom with simulated bone, lung, mediastinum, liver, and heart. (18)F was administered into the myocardium, mediastinum, right and left ventricular cavities, and liver. Plastic inserts (n = 11) ranging in size from 2% to 60% of the myocardium were used to simulate transmural myocardial infarctions. The chest phantom was imaged with a dedicated PET camera and with a double-head SPECT camera equipped with ultra-high-energy collimators. Both SPECT and PET data were analyzed using a semiquantitative polar map approach. Defects were quantified using various cutoff thresholds ranging from 30% to 80% of peak activity and were expressed as a percentage of the left ventricular myocardium. Defect size as measured by SPECT or PET was compared with true defect size. RESULTS The measured SPECT defect size was highly variable depending on the cutoff used, whereas PET defect size was relatively constant over the range of cutoffs tested. The mean absolute difference between measured and true defect sizes was minimal at a cutoff of 50% of peak activity for both SPECT (3.3% +/- 3.3%) and PET (2.7% +/- 2.5%). For this threshold, both SPECT and PET measurements showed an excellent correlation with true defect size (r = 0.98 for SPECT and 0.99 for PET). The correlation between SPECT and PET measurements was also excellent (r = 0.99; P < 0.01). CONCLUSION If an appropriate threshold is used to define a defect, SPECT with an (18)F-labeled agent can accurately measure defect size similarly to the manner of PET.
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[Dissecting aneurysm of the middle cerebral artery (M1-2 portion) with subarachnoid hemorrhage: a case report]. NO SHINKEI GEKA. NEUROLOGICAL SURGERY 2001; 29:347-52. [PMID: 11344915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
We report a SAH case of a ruptured dissecting aneurysm of the middle cerebral artery following parietooccipital subcortical hemorrhage. A 68-year-old woman was admitted to our hospital, complaining of headache. On admission she was alert with left homonymous hemianopsia. A CT scan disclosed subcortical hemorrhage in the right parieto-occipital lobe. An angiogram revealed no abnormal vessels. Seven days after admission, she suddenly lapsed into unconsciousness with left hemiparesis. A CT scan demonstrated subarachnoid hemorrhage with a right sylvian hematoma. A second angiogram revealed fusiform dilatation of the M2 branches and aneurysmal dilatation at the M1-M2 bifurcation. Following conservative therapy, she died 21 days after admission. The relationship between subcortical hemorrhage and the subsequent subarachnoid hemorrhage was not certain. We discuss and review the treatment of a dissecting aneurysm of the middle cerebral artery.
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Abstract
The met proto-oncogene is the tyrosine kinase growth factor receptor for hepatocyte growth factor. In the present study, we investigated the role of met expression on the modulation of apoptosis in colorectal tumours. The gene expressions of c-met and the anti-apoptotic bcl-2 family, including bcl-2, bcl-x(L)and bcl-w, were analysed in human colorectal adenomas and adenocarcinomas by using a quantitative polymerase chain-reaction combined with reverse transcription. In seven of 12 adenomas and seven of 11 carcinomas, the c-met gene was overexpressed. The bcl-w, bcl-2 and bcl-x(L)genes were over-expressed in nine, five and six of 12 adenomas and in five, two and seven of 11 carcinomas, respectively. The c-met mRNA level in human colorectal adenomas and carcinomas was correlated with bcl-w but not with bcl-2 or with bcl-x(L)mRNA level. The administration of c-met-antisense oligonucleotides decreased Met protein levels in the LoVo human colon cancer cell line. In the case of c- met -antisense-treated cells, apoptotic cell death induced by serum deprivation was more prominent, compared to control or c-met -nonsense-treated cells. Treatment with c-met-antisense oligonucleotides inhibits the gene expression of bcl-w in LoVo cells. On the other hand, the gene expression of bcl-2 or bcl-x(L)was not affected by treatment with c-met-antisense oligonucleotides. These findings suggest that Met expression modulates apoptosis through bcl -w expression in colorectal tumours.
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Mutations of the bak gene in human gastric and colorectal cancers. Cancer Res 2000; 60:4328-30. [PMID: 10969770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The Bcl-2 homologue Bak is a potent inducer of apoptosis. We performed PCR-based single-strand conformational polymorphism and sequencing analysis of the entire coding region of the bak gene (exons 2-6) in 24 primary gastric cancers (6 early-stage and 18 advanced-stage cancers) and 20 primary colorectal cancers (6 early-stage and 14 advanced-stage cancers). The data herein demonstrate, for the first time, the mutation of the bak gene in gastric and colorectal cancers. Missense bak gene mutations were observed in 3 of 24 (12.5%) gastric cancers and 2 of 20 (10.0%) colorectal cancers. Sequence alterations without amino acid alteration were observed 1 of 24 (4.2%) gastric cancers and 2 of 20 (10.0%) colorectal cancers. Mutations in the bak gene were observed only in advanced-stage gastrointestinal cancers but not in early-stage cancers. Our observations suggest that mutations in this gene predispose bearers to the development of gastrointestinal malignancies in at least a subset of the cases.
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Abstract
OBJECTIVE AND DESIGN This study was designed to determine if the hepatocyte growth factor (HGF)-Met system is involved in the repair process of inflamed mucosa of ulcerative colitis (UC) and in the development of UC-associated colorectal cancer. MATERIALS AND METHODS HGF and c-met gene expressions were quantified in colonic mucosal specimens from healthy control subjects, patients with UC and patients with UC-associated colorectal cancer, using the competitive reverse transcription-polymerase chain reaction. Expression of HGF protein was determined by immunoblot analysis. Expression of c-Met protein was analyzed immunohistochemically. RESULTS HGF and c-met gene expressions were increased in inflamed mucosa of UC, compared with control subjects. Gene expression of HGF was also increased in the surrounding inflamed mucosa of UC-associated cancers. In cases in which the HGF gene expression was increased, an apparent increase in protein levels of HGF in inflamed mucosa of UC were observed by immunoblot analysis. The c-met gene was overexpressed in UC-associated cancers and a high level of immunoreactivity of the c-Met protein was immunohistochemically detected within the cancer cells. CONCLUSION We showed that HGF and c-met expression is increased in the inflamed mucosa of UC and that c-met is overexpressed in UC-associated colorectal cancers. These observations suggest HGF-Met system is involved in the repair process of the inflamed mucosa of UC and provide further support for the view that the inappropriate expressions of both HGF and c-met genes predispose to the development of colorectal cancer in patients with UC.
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Abstract
OBJECTIVE CD40-CD40 ligand (CD40L) interaction is essential for the T-lymphocyte-dependent immune response. This interaction may be operational in the pathogenesis of inflammatory bowel diseases (IBD). The present study examined the expression of CD40 in peripheral blood mononuclear cells (PBMNCs) and tissue specimens, and CD40-stimulated interleukin (IL)-12 release from PBMNCs in IBD. METHODS The expression of CD40 in PBMNCs and tissue inflammatory cells was examined by flowcytometry and immunohistochemistry, respectively. IL-12 release was measured in cultured media of PBMNCs by an enzyme-linked immunosorbent assay. RESULTS Most peripheral blood B-lymphocytes expressed CD40 in all subjects. However, in ulcerative colitis (UC) patients, a significantly increased mean fluorescence intensity (MFI) of CD40 on B-lymphocytes was detected, compared with control subjects and patients with Crohn's disease (CD). In contrast, both the percentage positivity and MFI of CD40 on monocytes of active CD subjects were significantly increased, compared with the other groups. In active CD patients, a high level of IL-12 release from PBMNCs was observed by CD40 stimulation, compared with those of the other groups. When primed with IFN-gamma, PBMNCs from inactive CD patients released a significantly high level of IL-12, probably via stimulation by the CD40 monoclonal antibody. In the affected mucosa of CD, numerous CD40-positive cells were demonstrated, and they were also CD68-positive, suggesting these double CD40/ CD68-positive cells are tissue macrophages. CONCLUSIONS These results suggest that the examination of CD40 expression in PBMNCs might enable the differentiation of CD from UC. CD40-high monocytes in CD patients may play a role in the pathogenesis of CD.
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A quantitative index of intracranial cerebrospinal fluid distribution in normal pressure hydrocephalus using an MRI-based processing technique. Neuroradiology 2000; 42:424-9. [PMID: 10929302 DOI: 10.1007/s002349900241] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Our purpose was to quantify the intracranial cerebrospinal fluid (CSF) volume components using an original MRI-based segmentation technique and to investigate whether a CSF volume index is useful for diagnosis of normal pressure hydrocephalus (NPH). We studied 59 subjects: 16 patients with NPH, 14 young and 13 elderly normal volunteers, and 16 patients with cerebrovascular disease. Images were acquired on a 1.5-T system, using a 3D-fast asymmetrical spin-echo (FASE) method. A region-growing method (RGM) was used to extract the CSF spaces from the FASE images. Ventricular volume (VV) and intracranial CSF volume (ICV) were measured, and a VV/ICV ratio was calculated. Mean VV and VV/ICV ratio were higher in the NPH group than in the other groups, and the differences were statistically significant, whereas the mean ICV value in the NPH group was not significantly increased. Of the 16 patients in the NPH group, 13 had VV/ICV ratios above 30%. In contrast, no subject in the other groups had a VV/ICV ratios higher than 30%. We conclude that these CSF volume parameters, especially the VV/ICV ratio, are useful for the diagnosis of NPH.
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Morphological and functional restoration of parietal cells in helicobacter pylori associated enlarged fold gastritis after eradication. Gut 1999; 45:653-61. [PMID: 10517899 PMCID: PMC1727706 DOI: 10.1136/gut.45.5.653] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND/AIM Helicobacter pylori infections are associated with hypochlorhydria in patients with pangastritis. It has previously been shown that eradication of H pylori leads to an increase in acid secretion in H pylori associated enlarged fold gastritis, suggesting that H pylori infection affects parietal cell function in the gastric body. The aim of this study was to evaluate the effects of H pylori infection on parietal cell morphology and function in hypochlorhydric patients. PATIENTS/METHODS The presence of H pylori infection, mucosal length, and inflammatory infiltration were investigated in six patients with enlarged fold gastritis and 12 patients without enlarged folds. Parietal cell morphology was examined by immunohistochemistry using an antibody against the alpha subunit of H(+),K(+)-ATPase and electron microscopy. In addition, gastric acid secretion and fasting serum gastrin concentration were determined before and after the eradication of H pylori. RESULTS In the H pylori positive patients with enlarged fold gastritis, fold width, foveolar length, and inflammatory infiltration were increased. In addition, the immunostaining pattern of H(+), K(+)-ATPase was less uniform, and the percentage of altered parietal cells showing dilated canaliculi with vacuole-like structures and few short microvilli was greatly increased compared with that in H pylori positive patients without enlarged folds. After eradication, fold width, foveolar length, and inflammatory infiltrates decreased and nearly all parietal cells were restored to normal morphology. On the other hand, altered parietal cells were negligible in H pylori negative patients. In addition, the basal acid output and tetragastrin stimulated maximal acid output increased significantly from 0.5 (0.5) to 4.1 (1.5) mmol/h and from 2.5 (1.2) to 13.8 (0.7) mmol/h (p<0.01), and fasting serum gastrin concentrations decreased significantly from 213.5 (31.6) to 70.2 (7.5) pg/ml (p<0.01) after eradication in patients with enlarged fold gastritis. CONCLUSION The morphological changes in parietal cells associated with H pylori infection may be functionally associated with the inhibition of acid secretion seen in patients with enlarged fold gastritis.
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[A rare case of trapped fourth ventricle: an unique symptom appeared after fourth ventriculo-peritoneal shunting]. NO TO SHINKEI = BRAIN AND NERVE 1999; 51:247-51. [PMID: 10226289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
We experienced a unique case of trapped fourth ventricle after shunting for post-meningitic hydrocephalus. A five-year-old infant was diagnosed as meningitis shortly after his birth, and secondarily suffered from hydrocephalus. He underwent lateral-ventriculo-peritoneal shunting, fourth-ventriculo-cisterna-magna shunting and so on, but bilateral abducens palsy appeared. The following head CT and MRI revealed "trapped fourth ventricle". Though there are several case reports of trapped fourth ventricle with abducens palsy, most of them followed enlargement of the fourth ventricle; nevertheless in our case, abducens palsy appeared when the fourth ventricle reduced in size and the symptom vanished when it enlarged. We thought that a traction force to the abducens nerve had occurred also in the condition of reduced fourth ventricle size, because there would have been a dense adhesion after meningitis in his subarachnoidal space. We tried to improve his symptom in one way or another by keeping the fourth ventricle in appropriate volume. His abducens palsy was controlled by switching the on-off valve between forth ventricle and peritoneum. We expect that a higher-pressure programmable shunt valve or a lower-flow-regulating shunt system be invented in order to cope with the cases like ours.
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[Multiple aneurysms of the PICA communicating artery: a case report]. NO SHINKEI GEKA. NEUROLOGICAL SURGERY 1999; 27:177-82. [PMID: 10065451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
A case with unusual type of aneurysms in the distal posterior inferior cerebellar artery (PICA) is reported here. Though only two cases with a single aneurysm of the PICA communicating artery have been reported previously, the present case is the first one with multiple aneurysms in the PICA communicating artery. A 61-year-old woman with a sudden onset of severe headache, vomiting and unconsciousness was transferred to our hospital. CT scan revealed a hematoma in the fourth, third, and lateral ventricles, and a mild subarachnoid hemorrhage at the posterior fossa. Cerebral angiogram showed the right PICA supplying the hypoplastic left PICA territory through an anastomotic vessel. Two small aneurysms were seen at the tips of hairpin curves of an anastomotic vessel, "the PICA communicating artery". Suboccipital craniotomy was performed, and the ruptured aneurysm was clipped and the unruptured one was wrapped with cotton-sheet. After the operation, her clinical recovery went well and she was discharged on foot.
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Peroxisome proliferator-activated receptor gamma induces growth arrest and differentiation markers of human colon cancer cells. Jpn J Cancer Res 1999; 90:75-80. [PMID: 10076568 PMCID: PMC5925976 DOI: 10.1111/j.1349-7006.1999.tb00668.x] [Citation(s) in RCA: 195] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Peroxisome proliferator-activated receptor gamma (PPAR gamma), one of the nuclear receptors expressed in adipose tissue, plays an important role in adipocyte differentiation. In this study, we investigated the expression of PPAR gamma and its role in cellular growth and differentiation in six colon cancer cell lines: HT-29, CaCo-2, SW-480, DLD-1, LoVo, and T-84. All six expressed PPAR gamma mRNA and protein, shown respectively on northern and western blot analyses. Luciferase assay in HT-29 cells, which strongly express PPAR gamma, showed that troglitazone, a selective ligand for PPAR gamma, transactivated the transcription of a peroxisome proliferator response element (PPRE)-driven promoter. Furthermore, troglitazone caused a marked decrease in [3H]thymidine incorporation and G1 cell-cycle arrest determined by flow cytometry. Finally, troglitazone induced expression of mRNAs for villin and intestinal alkaline phosphatase, markers for enterocyte differentiation. In conclusion, human colon cancer cells express PPAR gamma, the ligands of which inhibit cell growth and induce differentiation markers.
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Determination of nucleotide sequence related to the plasmid replication region in Enterococcus faecalis and its application to a new shuttle vector. J Biosci Bioeng 1999; 87:566-71. [PMID: 16232519 DOI: 10.1016/s1389-1723(99)80115-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/1998] [Accepted: 01/19/1999] [Indexed: 11/21/2022]
Abstract
The 5.1-kb plasmid pAMalpha1delta2, a derivative of the 9.6-kb plasmid pAMalpha1 which is harbored by Enterococcus faecalis ATCC 14508, has a region necessary for replication in E. faecalis. The nucleotide sequence related to the replication region in pAMalpha1delta2 was determined and found to contain an open reading frame of 720-bp encoding a replication protein. The sequence showed 54.5 and 48.5% homology to those encoding the RepAs of plasmids pLA103 from Lactobacillus acidophilus and pFA3 from Neisseria gonorrhoeae, respectively. A recombinant 5.8-kb plasmid, pEFX6, which can be used as a shuttle vector between Escherichia coli and some strains of E. faecalis, was constructed by combining the tetracycline resistance gene of pAMalpha1delta2 and the replication regions of pAMalpha1delta2 and pUC18 for E. faecalis and E. coli, respectively. This shuttle vector was successfully used to clone and express the gelatinase gene from E. faecalis subsp. zymogenes IFO 3989 in E. faecalis C57, a strain showing no gelatinase activity.
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Gastrin induces heparin-binding epidermal growth factor-like growth factor in rat gastric epithelial cells transfected with gastrin receptor. Gastroenterology 1999; 116:78-89. [PMID: 9869605 DOI: 10.1016/s0016-5085(99)70231-3] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND & AIMS Parietal cells express heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF). However, it is unknown whether HB-EGF mediates the trophic action of gastrin. The purpose of this study was to determine whether gastrin modulates the expression of HB-EGF, which mediates the proliferative effects of gastrin on gastric epithelial cells. METHODS RGM1 cells, a rat gastric epithelial cell line, were transfected with a human gastrin receptor complementary DNA. Gastrin induction of messenger RNAs (mRNAs) for EGF-related polypeptides was assayed by Northern blotting. Processing of cell surface-associated proHB-EGF and secretion of HB-EGF were determined by flow cytometry and Western blotting, respectively. Tyrosine phosphorylation of the EGF receptor was assayed by immunoprecipitation and Western blotting with an antiphosphotyrosine antibody. Cell growth was evaluated by [3H]thymidine incorporation. RESULTS Gastrin induced expression of HB-EGF mRNA, processing of proHB-EGF, release of HB-EGF into the medium, and tyrosine phosphorylation of the EGF receptor. The growth-stimulatory effects of gastrin were partly inhibited by anti-rat HB-EGF serum and completely blocked by AG1478, an EGF receptor-specific tyrphostin. CONCLUSIONS The findings suggest that HB-EGF at least partially mediates the proliferative effects of gastrin on gastric epithelial cells.
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[Proton-pump inhibitors versus H2-receptor antagonists in triple therapy for Helicobacter pylori eradication]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 1999; 57:153-6. [PMID: 10036954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Triple therapy with two antibiotics and acid-suppressing drugs is widely accepted for H. pylori eradication. Both H2-receptor antagonist and proton-pump inhibitor are reported to enhance the eradication rate when antibiotics are administered together. Comparative studies using H2-receptor antagonist or proton-pump inhibitor in triple therapy were reviewed. The efficacy of H. pylori eradication regimens with H2-receptor antagonist or proton-pump inhibitor with two antibiotics is not significantly different.
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Abstract
This study was designed to clarify the role of endogenous Bcl-xL expression in modulating apoptosis of malignant cells. Administration of bcl-x-antisense oligonucleotides decreased Bcl-xL protein levels in the MKN-45 human gastric cancer cell line. The decrease in Bcl-xL protein content resulted in increased cell death induced by serum deprivation or Fas-antibody administration. Flow cytometric analysis revealed that the increased apoptotic cell death was more prominent in bcl-x-antisense-treated cells as compared to control cells, bcl-x-sense-treated cells, or bcl-x-nonsense-treated cells. To inhibit the effect of intrinsic Bcl-xL protein, we overexpressed Bak, which binds Bcl-xL and inhibits the anti-apoptotic effect of Bcl-xL, by transfection into MKN-45 cells. Bak-overexpressing cells showed increased apoptotic cell death induced by Fas-antibody when compared to parent cells and MKN-neo-transfected cells. Bak-overexpressing cells also showed greater sensitization to 5-fluorouracil and cisplatin than parent cells and MKN-neo-transfected cells. In conclusion, we demonstrated that administration of bcl-x-antisense oligonucleotides or overexpression of Bak protein induces sensitization to apoptosis in MKN-45 gastric cancer cells, suggesting that endogenous Bcl-xL expression in cancer cells is an important modulator of apoptosis.
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Abstract
BACKGROUND & AIMS The c-kit gene encodes a receptor tyrosine kinase (KIT). Recently, we found gain-of-function mutations of the c-kit gene in gastrointestinal stromal tumors (GISTs). All mutations were confined within the 11 amino acids (Lys-550 to Val-560) in the juxtamembrane domain, but one GIST showed a novel deletion-type mutation at codon 579 (Asp) in the juxtamembrane domain. The aim of this study was to clarify whether the mutation is activating. METHODS Mutant c-kit cDNA was transfected into an interleukin 3 (IL-3)-dependent Ba/F3 murine lymphoid cell line, and the magnitude of autophosphorylation of the mutant KIT was examined with or without stem cell factor (SCF), a ligand of KIT. An in vitro kinase assay was also performed. The biological behavior of the transfectant was estimated by both an in vitro proliferation assay and in vivo transplantation to nude mice. RESULTS The mutant KIT exhibited constitutive phosphorylation and strong kinase activity without SCF. The transfectant grew autonomously without IL-3 and SCF, and it formed tumors in nude mice. CONCLUSIONS Deletion at codon 579 (Asp) in the juxtamembrane domain of the c-kit gene is a novel gain-of-function mutation other than the region between Lys-550 and Val-560.
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Abstract
The oncogenic ras mutation is a common and critical step in gastrointestinal carcinogenesis. In a previous study, we demonstrated that oncogenic ras activated the EGF-related peptide autocrine loop and that the apoptosis resistance observed in the oncogenic ras-stimulated cell (IEC-ras cell) was dependent on this activated EGF-related peptide autocrine loop. STATs (signal transducers and activators of transcription), first identified as intracellular signal transducers stimulated by cytokines, are known to also be activated by EGF. However, the role of STATs in the survival signal of IEC-ras cells is not clear. In the present study, we demonstrate that STAT3 is constitutively activated in ras-stimulated cells and that STAT3 activation is considerably suppressed by the EGF-specific receptor kinase inhibitor AG 1478. We also show that disruption of the STAT3 pathway by introduction of a dominant-negative STAT3 mutant abolishes the apoptosis resistance against UVC and MMC treatment observed in IEC-ras cells without affecting proliferation. Moreover, the expression of Bcl-2 and Bcl-xL, apoptosis-suppressive proteins, is reduced in dominant-negative STAT3-transfected cells. Thus, STAT3 appears to be an important mediator of the antiapoptotic signal in IEC-ras cells.
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Differential diagnosis of NPH and brain atrophy assessed by measurement of intracranial and ventricular CSF volume with 3D FASE MRI. ACTA NEUROCHIRURGICA. SUPPLEMENT 1998; 71:371-4. [PMID: 9779233 DOI: 10.1007/978-3-7091-6475-4_107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Differential diagnosis of NPH and brain atrophy is sometimes difficult. Recently, a new method using MRI was introduced as a noninvasive, direct technique for the measurement of intracranial CSF volume. Using this new technique, we measured the intracranial and ventricle CSF volume in patients with enlarged ventricles in order to differentiate between NPH and brain atrophy. Ten healthy volunteers (control group) and 21 patients with enlarged ventricles were enrolled in this study. Eleven out of 21 patients were clinically diagnosed as having NPH (shunted group) and the remaining 10 patients were considered to have cerebral atrophy (non-shunted group). Intracranial and ventricular CSF volume in each case were measured by 3D FASE (Fast Asymmetric Spine-Echo) MR imaging sequence with region growing method. Ventricular/intracranial CSF volume ratio was also calculated. Ten out of 11 patients showed improvement in clinical symptoms and/or dementia scale after shunting. Our results clearly indicate that the ventricular volume in the shunted group was enlarged and that the ventricular/intracranial CSF ratio was significantly high. Thus we concluded that enlarged ventricle with high ventricular/intracranial CSF volume ratio strongly suggests NPH.
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Abstract
BACKGROUND The pathogenesis of ulcerative colitis is unclear, but cytotoxic T lymphocytes infiltrating the mucosa have been implicated in mucosal damage. The Fas ligand (FasL), expressed on cytotoxic T lymphocytes, induces apoptosis in cells expressing Fas. AIM To analyse FasL expression in affected colonic mucosa to ascertain Fas-FasL interaction in ulcerative colitis. METHODS FasL mRNA was quantified in colonic mucosal specimens from healthy subjects and patients with ulcerative colitis or Crohn's disease, using the competitive reverse transcription polymerase chain reaction. FasL mRNA localisation was determined by in situ hybridisation. Expression of Fas in colonic mucosa was analysed immunohistochemically. Phenotypes of lamina propria lymphocytes that expressed FasL were analysed by flow cytometry. RESULTS FasL mRNA was strongly expressed in active ulcerative colitis lesions, but not in those associated with active Crohn's disease or active proctitis-type ulcerative colitis. In situ hybridisation showed that FasL mRNA expression occurred in mononuclear cells infiltrating lesions. Fas was expressed in epithelial cells in ulcerative colitis and Crohn's disease, and in normal subjects. Cytometry showed that FasL was expressed in CD3 lymphocytes infiltrating the lamina propria in active lesions. CONCLUSIONS FasL is expressed in CD3 lymphocytes infiltrating into ulcerative colitis but not Crohn's disease lesions, suggesting that Fas-FasL induced apoptosis participates in the mucosal damage of ulcerative colitis.
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Role of heparin-binding EGF-related peptides in proliferation and apoptosis of activated ras-stimulated intestinal epithelial cells. Int J Cancer 1998. [PMID: 9399676 DOI: 10.1002/(sici)1097-0215(19971210)73:6<917::aid-ijc26>3.0.co;2-#] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The ras mutation is a common and critical step in carcinogenesis. Autocrine growth factors are also known to play an important role in cancer cell growth and transformation. However, the contribution of autocrine growth factors in regulation of proliferation and apoptosis of activated ras-stimulated intestinal epithelium is not fully understood. Therefore, we constructed activated ras-transfected intestinal epithelial cell clones (IEC-ras) to examine the role of epidermal growth factor (EGF)-related peptides in the behavior of IEC-ras. Overexpression of EGF family growth factors (transforming growth factor alpha, heparin-binding EGF-like growth factor, amphiregulin and betacellulin) and stronger phosphorylation of the EGF receptor was observed in IEC-ras compared with control cells. IEC-ras proliferated more rapidly than control cells, and a specific EGF receptor kinase inhibitor, AG 1478, abolished the increased proliferation of IEC-ras. Heparitinase and chlorate also prevented increased proliferation of IEC-ras. Additionally, IEC-ras expressed more bcl-2 and was more resistant to apoptosis induction by UV radiation and mitomycin C. AG 1478 suppressed bcl-2 expression and inhibited resistance to apoptosis of IEC-ras. Heparitinase and chlorate had effects similar to those of AG 1478. Our data indicate that heparin-binding EGF family growth factors play an important role in both increased proliferation and resistance to apoptosis of ras-stimulated intestinal epithelial cells.
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Role of heparin-binding EGF-related peptides in proliferation and apoptosis of activated ras-stimulated intestinal epithelial cells. Int J Cancer 1997; 73:917-23. [PMID: 9399676 DOI: 10.1002/(sici)1097-0215(19971210)73:6<917::aid-ijc26>3.0.co;2-#] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The ras mutation is a common and critical step in carcinogenesis. Autocrine growth factors are also known to play an important role in cancer cell growth and transformation. However, the contribution of autocrine growth factors in regulation of proliferation and apoptosis of activated ras-stimulated intestinal epithelium is not fully understood. Therefore, we constructed activated ras-transfected intestinal epithelial cell clones (IEC-ras) to examine the role of epidermal growth factor (EGF)-related peptides in the behavior of IEC-ras. Overexpression of EGF family growth factors (transforming growth factor alpha, heparin-binding EGF-like growth factor, amphiregulin and betacellulin) and stronger phosphorylation of the EGF receptor was observed in IEC-ras compared with control cells. IEC-ras proliferated more rapidly than control cells, and a specific EGF receptor kinase inhibitor, AG 1478, abolished the increased proliferation of IEC-ras. Heparitinase and chlorate also prevented increased proliferation of IEC-ras. Additionally, IEC-ras expressed more bcl-2 and was more resistant to apoptosis induction by UV radiation and mitomycin C. AG 1478 suppressed bcl-2 expression and inhibited resistance to apoptosis of IEC-ras. Heparitinase and chlorate had effects similar to those of AG 1478. Our data indicate that heparin-binding EGF family growth factors play an important role in both increased proliferation and resistance to apoptosis of ras-stimulated intestinal epithelial cells.
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Abstract
BACKGROUND We have previously shown that eradication of Helicobacter pylori increases acid secretion in H. pylori-associated enlarged fold gastritis. AIM To investigate whether locally produced interleukin-1 beta is possibly involved in the inhibition of acid secretion in H. pylori gastritis. METHODS IL-1 beta release from the gastric body mucosa was determined by short-term culture of biopsy specimens in 13 patients with enlarged fold gastritis (all H. pylori-positive), five H. pylori-positive and 10 H. pylori-negative patients without enlarged folds. The acid-inhibitory effect of locally produced IL-1 beta was examined by [14C]-aminopyrine uptake assay using isolated rabbit gastric glands. RESULTS IL-1 beta release was significantly greater in patients with enlarged fold gastritis, significantly correlated with both basal and tetragastrin-stimulated acid outputs in the H. pylori-positive patients (r = -0.591 and r = -0.641, respectively; P < 0.01), and significantly decreased with concomitant increases in acid secretions after eradication of H. pylori. [14C]-aminopyrine uptake was inhibited by IL-1 beta in a dose-dependent manner. CONCLUSIONS Increased production of IL-1 beta caused by H. pylori infection is possibly involved in the inhibition of acid secretion in enlarged fold gastritis.
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High prevalence of serum immunoglobulin G antibody to Helicobacter pylori and raised serum gastrin and pepsinogen levels in enlarged fold gastritis. CANADIAN JOURNAL OF GASTROENTEROLOGY = JOURNAL CANADIEN DE GASTROENTEROLOGIE 1997; 11:433-6. [PMID: 9286479 DOI: 10.1155/1997/437467] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To clarify the prevalence of Helicobacter pylori infection in enlarged fold gastritis, serum immunoglobulin (Ig) G antibody to H pylori was determined in 19 patients with severely enlarged gastric body folds (the widest fold greater than 10 mm on the radiograph), 55 patients with moderately enlarged folds (6 to 10 mm) and 44 control subjects (5 mm or less). The prevalence of serum IgG antibody to H pylori in the severe (100%) and moderate groups (100%) was significantly higher than that in controls (34.1%) (P < 0.01). There were significant differences among the three groups in serum gastrin, pepsinogen I and pepsinogen II levels (severe had the highest levels, followed by moderate and then controls, P < 0.001). H pylori colonization in the gastric mucosa was confirmed by culture, urease test or both, and inflammation by hematoxylin and eosin stain in the 25 H pylori seropositive patients who underwent endoscopy and biopsy. Results suggest that H pylori infection is highly prevalent in enlarged fold gastritis. Further studies on enlarged fold gastritis and H pylori infection are needed.
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Induction of heparin binding epidermal growth factor-like growth factor and amphiregulin mRNAs by gastrin in the rat stomach. Biochem Biophys Res Commun 1997; 235:520-3. [PMID: 9207188 DOI: 10.1006/bbrc.1997.6824] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The present study was designed to investigate whether heparin-binding epidermal growth factor-like growth factor and its related peptides are expressed in response to gastrin in rat stomach. Rat gastrin-17I (2.5 nmol/kg/hour) or gastrin-17I plus gastrin receptor antagonist, L-740,093 (2.0 mg/kg/hour), was injected intravenously into male Sprague-Dawley rats. RNA was extracted from oxyntic mucosa, and heparin-binding epidermal growth factor-like growth factor and related peptide gene expression was estimated using a ribonuclease protection assay. The level of transforming growth factor-alpha mRNA did not change at any time point during the experiment. In contrast, the levels of heparin-binding epidermal growth factor-like growth factor and amphiregulin mRNA were significantly increased within 3 hours following gastrin infusion and reached maximum levels 6 and 12 hours later, respectively. Continuous infusion of gastrin significantly increased oxyntic mucosal proliferation. Gastrin receptor antagonist significantly inhibited gastrin-induced heparin-binding epidermal growth factor-like growth factor and amphiregulin gene expression and gastrin-induced oxyntic mucosal proliferation. These findings indicate that heparin-binding epidermal growth factor-like growth factor and amphiregulin genes are induced by gastrin and that they play a role in the trophic action of gastrin on oxyntic mucosa.
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Delayed gastric emptying during interferon-alpha therapy in patients with chronic hepatitis C: relief by cisapride. Scand J Gastroenterol 1997; 32:547-51. [PMID: 9200285 DOI: 10.3109/00365529709025097] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Patients receiving interferon-alpha often experience symptoms such as upper abdominal discomfort, anorexia, and nausea, which suggest a delay in gastric emptying. Reduction of the dosages of interferon-alpha or even interruption of the treatment is sometimes required because of these symptoms. The present study was designed to investigate the effect of interferon-alpha on gastric emptying and to evaluate the effects of cisapride on gastric emptying and upper abdominal symptoms during interferon-alpha therapy. METHODS Gastric emptying in 14 patients with chronic hepatitis C was estimated by the sulfamethizole capsule method before and 1 and 2 weeks after the beginning of interferon-alpha (6 million U/day) therapy. RESULTS Before therapy none of the patients complained of upper abdominal symptoms, and all had normal gastric emptying. Interferon treatment delayed gastric emptying in 12 of the patients and induced discomfort and anorexia in 9 of the patients. The administration of cisapride reversed the delayed gastric emptying in six of seven patients and relieved abdominal discomfort and anorexia. CONCLUSIONS These findings indicate that interferon-alpha delays gastric emptying and suggest that cisapride administration corrects the delayed gastric emptying and relieves the abdominal symptoms associated with interferon-alpha therapy.
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Abstract
The present study was designed to clarify whether bcl-xL is involved in the development of carcinoma in the stomach. Levels of bcl-xL and bcl-2 mRNA were determined by a reverse-transcription/polymerase-chain reaction in endoscopic gastric biopsy specimens from 10 control subjects, 11 patients with adenomas and 14 patients with carcinomas. In 6 of 11 adenomas, 5 of 8 early carcinomas and 3 of 6 advanced carcinomas, the bcl-xL gene was over-expressed. In carcinomas, over-expression of the bcl-xL gene was observed in 6 of 9 intestinal-type carcinomas and 2 of 5 diffuse-type carcinomas. No correlation was observed between bcl-xL and bcl-2 gene expression. In cases in which the bcl-xL gene was over-expressed, an apparent increase in the protein level of Bcl-xL was observed by immunoblot analysis and intense Bcl-x immunoreactivity was detected immunohistochemically within the tumor cells. In conclusion, we showed that bcl-xL is over-expressed in gastric carcinomas at both the RNA and protein levels, suggesting that over-expression of bcl-xL may play a role in gastric carcinogenesis.
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Abstract
The present study was designed to clarify whether bcl-xL is involved in the development of carcinoma in the stomach. Levels of bcl-xL and bcl-2 mRNA were determined by a reverse-transcription/polymerase-chain reaction in endoscopic gastric biopsy specimens from 10 control subjects, 11 patients with adenomas and 14 patients with carcinomas. In 6 of 11 adenomas, 5 of 8 early carcinomas and 3 of 6 advanced carcinomas, the bcl-xL gene was over-expressed. In carcinomas, over-expression of the bcl-xL gene was observed in 6 of 9 intestinal-type carcinomas and 2 of 5 diffuse-type carcinomas. No correlation was observed between bcl-xL and bcl-2 gene expression. In cases in which the bcl-xL gene was over-expressed, an apparent increase in the protein level of Bcl-xL was observed by immunoblot analysis and intense Bcl-x immunoreactivity was detected immunohistochemically within the tumor cells. In conclusion, we showed that bcl-xL is over-expressed in gastric carcinomas at both the RNA and protein levels, suggesting that over-expression of bcl-xL may play a role in gastric carcinogenesis.
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Increased production of interleukin 1 beta and hepatocyte growth factor may contribute to foveolar hyperplasia in enlarged fold gastritis. Gut 1996; 39:787-94. [PMID: 9038658 PMCID: PMC1383448 DOI: 10.1136/gut.39.6.787] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND AND AIMS It has been reported that eradication of Helicobacter pylori improves fold width in H pylori associated enlarged fold gastritis. The aim of this study was to clarify the mechanism of fold thickening in this condition. PATIENTS AND METHODS In eight patients with enlarged fold gastritis and 13 patients without enlarged folds, the presence of H pylori infection, inflammatory infiltrates, mucosal plasia, and epithelial cell proliferation in the body mucosa were investigated, and production of transforming growth factor alpha (TGF alpha), hepatocyte growth factor (HGF), and interleukin 1 beta (IL 1 beta) was determined by a competitive reverse transcription/polymerase chain reaction method and in vitro short-term culture of biopsy specimens. RESULTS In the patients with enlarged fold gastritis, inflammatory infiltrates including macrophages increased with H pylori colonisation in the body. Foveolar thickness and proliferating cell nuclear antigen (PCNA) labelling index were increased. Messenger RNA levels of HGF, but not TGF alpha, were increased, and release of HGF and IL 1 beta was increased. HGF release, which was positively correlated with IL 1 beta release and foveolar thickness, decreased in the presence of IL 1 receptor antagonist. After eradication of H pylori, inflammatory infiltrates, IL 1 beta and HGF release decreased with concomitant decreases in PCNA labelling index, foveolar thickness and fold width. CONCLUSIONS Increased IL 1 beta and HGF production caused by H pylori infection may contribute to fold thickening of the stomach by stimulating epithelial cell proliferation and foveolar hyperplasia in patients with enlarged fold gastritis.
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In vivo rapid magnetic field measurement and shimming using single scan differential phase mapping. Magn Reson Med 1996; 36:637-42. [PMID: 8892219 DOI: 10.1002/mrm.1910360421] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In vivo shimming is a powerful tool for alleviating subject-dependent magnetic field distortions in MRI, although the usually lengthy procedure has limited its use. A magnetic field measurement method called single scan differential phase mapping that can reduce the measurement time of conventional methods by more than half when used with multiple gradient-recalled echo imaging was developed. An automatic high-order shimming using the present method was implemented in a commercial MRI system. In vivo field inhomogeneity features and the shimming performances were investigated. The method was found to be useful for improving the quality of echo-planar images.
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