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41.
Ana L Sanchez Carrie M Langdon Mahmood Akhtar Jun Lu Carl D Richards Premysl Bercik Derek M McKay 《Journal of interferon & cytokine research》2003,23(4):193-201
The use of biologics has promising potential in the treatment of inflammation. Studies with cultured cells and mouse models of disease have ascribed proinflammatory and anti-inflammatory functions to oncostatin M (OSM) and the related cytokine, interleukin-6 (IL-6). Here, we examined the effect of systemic administration of adenoviral (Ad) vectors encoding either murine OSM (AdMuOSM) or murine IL-6 (AdMuIL-6) in a mouse model of colitis. BALB/c mice were treated with a 5-day course of 4% dextran-sodium sulfate (DSS) water with or without administration of adenoviral vectors (i.p. or i.m. at 10(7) plaque-forming units [pfu]) given as a cotreatment or therapy. The deletion variant of the adenovirus served as a control for adenoviral infection. Colitis was assessed by (1) morphology (damage score, macrophage infiltration, apoptosis) and (2) function (myeloperoxidase activity and Ussing chamber analysis of epithelial ion transport). Infection with adenovirus alone did not affect colonic form or function. AdMuOSM (either i.p. or i.m.) significantly reduced the severity of the DSS-induced colitis. There was less damage, reduced macrophage infiltration, fewer apoptotic bodies, and a significant improvement in stimulated ion transport in colonic tissues from the treated mice. No benefit of AdMuIL-6 treatment was observed in this model system. Thus, systemic administration of AdMuOSM given as a cotreatment and to a lesser extent as a therapy was found to be of benefit in DSS-induced colitis, a murine model of inflammatory bowel disease (IBD). 相似文献
42.
Differential pattern of DNA-aneuploidy in human malignancies 总被引:5,自引:0,他引:5
Th Büchner W Hiddemann B Wörmann B Kleinemeier J Schumann W Göhde J Ritter K.-M Müller DB von Bassewitz A Roessner E Grundmann 《Pathology, research and practice》1985,179(3):310-317
The differential pattern of DNA-aneuploidy, detected by flow cytometry (FCM) regarding its frequency, grade and multiclonality, was investigated and correlated to tumor type, malignancy grade, tumor stage and prognosis in a multi-institutional study at the University of Münster. High resolution measurements using admixed normal blood reference cells were undertaken in 2413 cases of 13 different malignant diseases and in 776 benign lesions or samples. The incidence of DNA-aneuploidy was highest in melanomas, carcinomas, testicular tumors, sarcomas (75%-95%) and myelomas (65%). Acute leukemias showed an intermediate DNA-aneuploidy rate of 40% with special subgroups represented by common ALL (44%), p less than 0.05) and myelomonocytic/monocytic AML (47%, p less than 0.01). The lowest DNA-aneuploidy-rate was found in basal cell skin carcinomas (19%) and congenital melanocytic nevi (9%). No case of DNA-aneuploidy was observed in the 776 benign lesions or samples.--DNA-indices giving the grade of DNA-aneuploidy with 1.0 for normal diploid G1/0 cells were found distributed predominantly between 1.0 and 2.0 in the solid tumors, except testicular tumors, clustering around a triploid maximum at 1.5. DNA-indices of myelomas and acute leukemias generally ranged below 1.25 with lower DNA-aneuploidy grades in AML than in ALL (p less than 0.01).--In melanomas the aneuploidy rate was higher (86%) in metastases than in the primary tumors (54%, p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
43.
D. M. McKay D. W. Halton C. F. Johnston I. Fairweather C. Shaw 《Parasitology research》1990,76(6):509-517
The localistion and distribution of the cholinergic, serotoninergic and peptidergic components of the nervous system of the frog-lung flukeHaplometra cylindracea have been determined by the application of standard enzyme cytochemical and immunocytochemical techniques to cryostat sections and whole-mount preparations. Cholinesterase activity (ChE), as indicative of acetylcholine, has been demonstrated cytochemically in the CNS and PNS; however, the anterior ganglia were notably unreactive. The occurrence of serotonin was examined by an indirect immunofluorescence technique, and immunoreactivity (IR) was demonstrable in small, paired anterior ganglia and in fine nerve fibres associated with the somatic muscle, cirrus and gonopore. The peptidergic protion of the nervous system was investigated using antisera to 17 mammalian regulatory peptides and the invertebrate peptide FMRFamide, and was visualised by both indirect immunofluorescence and confocal scanning laser microscopy. Positive immunostaining occurred with antisera raised against pancreatic polypeptide (PP), peptide tyrosine tyrosine (PYY), substance P (SP), peptide histidine isoleucine (PHI) and FMRFamide. Immunoreactivity to PP, PYY and FMRFamide was widespread throughout the nervous system and was evident in large, paired anterior ganglia, the dorsal commissure, main nerve tracts and the extensive array of small fibres that constitute the PNS. In contrast, the distribution of nerves immunoreactive to SP and PHI was less apparent, with PHI-IR occurring exclusively within the fibrous neuropile of the ganglia and in fibres of the ventral nerve cord. Results are discussed with respect to the distribution of the various neurochemical elements and their roles as putative neurotransmitters and/or regulatory molecules. 相似文献
44.
McKay JD Thompson D Lesueur F Stankov K Pastore A Watfah C Strolz S Riccabona G Moncayo R Romeo G Goldgar DE 《Journal of medical genetics》2004,41(6):407-412
Background: Familial non-medullary thyroid cancer (fNMTC) is a complex genetic disorder that is more aggressive than its sporadic counterpart. Thus far, three genetic loci have been implicated in susceptibility to fNMTC by linkage analysis. Methods: We used linkage analysis to test the significance of two of the known susceptibility loci for fNMTC, TCO on 19p13 and NMTC1 on 2q21 in 10 fNMTC families, nine of which present with cell oxyphilia, a rare histological phenotype associated with TCO. Furthermore, we used two-locus linkage analysis to examine the possibility that the TCO and NMTC1 loci interact to increase the risk of NMTC. Results: The 10 families provided evidence for linkage at both TCO and NMTC, with LOD scores of 1.56 and 2.85, respectively. Two-locus linkage analysis, using a multiplicative risk model for the development of NMTC, achieved a maximum LOD of 3.92, with an LOD of 4.51 when assuming 70% of families were linked, indicating that the segregation in these families is consistent with an interaction model. Most of this evidence came from a large Tyrolean family that singularly achieved a two-locus LOD of 3.21. Conclusions: These results provide further evidence that susceptibility genes for fNMTC exist at 19p13 and 2q21, and furthermore, raise the possibility that in a subset of fNMTC pedigrees, these loci interact resulting in significantly increased risk of NMTC for patients that carry both susceptibility loci. 相似文献
45.
Monoclonal antibodies to a rat nestin fusion protein recognize a 220-kDa polypeptide in subsets of fetal and adult human central nervous system neurons and in primitive neuroectodermal tumor cells. 总被引:3,自引:1,他引:3 下载免费PDF全文
T. Tohyama V. M. Lee L. B. Rorke M. Marvin R. D. McKay J. Q. Trojanowski 《The American journal of pathology》1993,143(1):258-268
Nestin is the major intermediate filament protein of embryonic central nervous system (CNS) progenitor cells. To identify proteins involved in early stages of lineage commitment in the developing human CNS we generated monoclonal antibodies to a TrpE-rat nestin fusion protein. This resulted in a monoclonal antibody (designated NST11) that did not recognize authentic human nestin, but did recognize a novel neuron-specific human polypeptide expressed in a subset of embryonic and adult CNS neurons as well as in medulloblastomas. NST11 immunoreactivity was abundant in developing spinal cord motor neurons, but was extinguished in these neurons by 17 weeks gestation. NST11 also labeled Purkinje cells at 17 weeks gestation, but Purkinje cells continued to express the NST11 antigen throughout gestation as well as in the adult cerebellum, and NST11 immunoreactivity was more abundant in Purkinje cells than in any other human CNS neurons. No NST11 immunoreactivity was detected in cells of the adult human peripheral nervous system or in a variety of adult non-neural human tissues. Further, NST11 almost exclusively stained cerebellar medulloblastomas. In Western blots of immature and mature human cerebral and cerebellar extracts, NST11 did not bind human nestin, but did detect an immunoband with a molecular weight of 220 kd. A similar immunoband was detected in medulloblastoma-derived cell lines with a neuron-like phenotype. These findings suggest that the NST11 monoclonal antibody recognizes a novel protein expressed by a subpopulation of immature and mature human CNS neurons, medulloblastomas, and medulloblastoma-derived cell lines. 相似文献
46.
D. S. Stokic´ W. Barry McKay Lillian Scott Arthur M. Sherwood Milan R. Dimitrijevic´ 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,117(3):437-443
The aim of the present study was to determine the characteristics of intracortical inhibition in the motor cortex areas representing
lower limb muscles using paired transcranial magnetic (TMS) and transcranial electrical stimulation (TES) in healthy subjects.
In the first paradigm (n=8), paired magnetic stimuli were delivered through a double cone coil and motor evoked potentials (MEPs) were recorded from
quadriceps (Q) and tibialis anterior (TA) muscles during relaxation. The conditioning stimulus strength was 5% of the maximum
stimulator output below the threshold MEP evoked during weak voluntary contraction of TA (33±5%). The test stimulus (67±2%)
was 10% of the stimulator output above the MEP threshold in the relaxed TA. Interstimulus intervals (ISIs) from 1–15 ms were
examined. Conditioned TA MEPs were significantly suppressed (P<0.01) at ISIs of less than 5 ms (relative amplitude from 20–50% of the control). TA MEPs tended to be only slightly facilitated
at 9-ms and 10-ms ISIs. The degree of MEP suppression was not different between right and left TA muscles despite the significant
difference in size of the control responses (P<0.001). Also, conditioned MEPs were not significantly different between Q and TA. The time course of TA MEP suppression,
using electrical test stimuli, was similar to that found using TMS. In the second paradigm (n=2), the suppression of TA MEPs at 2, 3, and 4 ms ISIs was examined at three conditioning intensities with the test stimulation
kept constant. For the pooled 2- to 4-ms ISI data, relative amplitudes were 34±6%, 61±5%, and 98±9% for conditioning intensities
of 0.95, 0.90, and 0.85× active threshold, respectively (P<0.01). In conclusion, the suppression of lower limb MEPs following paired TMS showed similar characteristics to the intracortical
inhibition previously described for the hand motor area.
Received: 21 June 1996 / Accepted: 23 May 1997 相似文献
47.
48.
The antiflammatory drug indomethacin, an inhibitor of prostaglandin synthesis, prevents the generalized Shwartzman reaction produced in rabbits by two intravenous injections of bacterial endotoxin. Indomethacin has this effect if given before the first but not the second injection of endotoxin. Measurements of circulating white blood cells, platelets, partial thromboplastin time, prothrombin time, fibrinogen, plasminogen, and soluble fibrin were made at several times after either the first or second injection of endotoxin treated and nontreated rabbits. Four hours after the first injection of endotoxin, leukopenia and thrombocytopenia were somewhat greater in treated rabbits and the prolongation of the activated partial thromboplastin time was shortened. Twenty-one hours after injection of endotoxin, leukocytosis and elevation of plasma fibrinogen were not as great in treated animals. Four hours following the second injection of endotoxin a decrease in fibrinogen, prolongation of the prothrombin time, and the elaboration of soluble fibrin were consistently found in rabbits with the generalized Shwartzman reaction. In treated rabbits, none of these changes occurred. Indomethacin prevents the generalized Shwartzman reaction by preventing the development of the prepared state in this endotoxin model. 相似文献
49.
We evaluated a simple, specific method for measuring plasma creatinine concentration, involving enzymatic degradation of creatinine before analysis by a kinetic Jaffé reaction. The enzymes--prepared in a dry, stable form--are convenient to use and eliminate the need to correct for sample dilution. As little as 50 microL of plasma is required, making the procedure ideal for use with samples from children. Between-day precision studies for determination of plasma creatinine at concentrations of 70 and 470 mumol/L yielded CVs of 7.8 and 4.3%, respectively. Analytical recovery of creatinine added to plasma samples ranged from 94 to 113%. Linear regression analysis demonstrated excellent agreement between results by this method and those by a "high performance" liquid-chromatographic technique. 相似文献
50.
Siobhan C. McKay Hanns Lembach Angus Hann Kelvin Okoth Joy Anderton Krishnarajah Nirantharakumar Laura Magill Barbara Torlinska Matthew Armstrong Jorge Mascaro Nicholas Inston Thomas Pinkney Aaron Ranasinghe Richard Borrows James Ferguson John Isaac Melanie Calvert M. Thamara P. R. Perera Hermien Hartog 《Transplant international》2021,34(11):2122-2137
Strict isolation of vulnerable individuals has been a strategy implemented by authorities to protect people from COVID-19. Our objective was to investigate health-related quality of life (HRQoL), uncertainty and coping behaviours in solid organ transplant (SOT) recipients during the COVID-19 pandemic. A cross-sectional survey of adult SOT recipients undergoing follow-up at our institution was performed. Perceived health status, uncertainty and coping strategies were assessed using the EQ-5D-5L, Short-form Mishel Uncertainty in Illness Scale (SF-MUIS) and Brief Cope, respectively. Interactions with COVID-19 risk perception, access to health care, demographic and clinical variables were assessed. The survey was completed by 826 of 3839 (21.5%) invited participants. Overall, low levels of uncertainty in illness were reported, and acceptance was the major coping strategy (92%). Coping by acceptance, feeling protected, self-perceived susceptibility to COVID-19 were associated with lower levels of uncertainty. Health status index scores were significantly lower for those with mental health illness, compromised access to health care, a perceived high risk of severe COVID-19 infection and higher levels of uncertainty. A history of mental health illness, risk perceptions, restricted healthcare access, uncertainty and coping strategies was associated with poorer HRQoL in SOT recipients during strict isolation. These findings may allow identification of strategies to improve HRQoL in SOT recipients during the pandemic. 相似文献