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21.
Robin Hutchinson 《Macromolecular chemistry and physics.》2006,207(15):1414-1415
Conference Reports: This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de. 相似文献
22.
J E Fildes A H Walker C G Densem A K Deiraniya I V Hutchinson C T Leonard N Yonan 《The Journal of heart and lung transplantation》2005,24(4):406-410
BACKGROUND: The angiotensin converting enzyme insertion deletion polymorphism (ACE I/D) has been associated with much cardiovascular pathology, including posttransplantation hypertension. Hypertension is a significant cause of morbidity and mortality after cardiac transplantation. We investigated the influence of the ACE I/D polymorphism on posttransplantation hypertension. METHODS: A total of 211 heart transplant recipients and 154 corresponding donors were genotyped for the ACE I/D polymorphism by polymerase chain reaction. ACE enzymatic activity was measured by spectrophotometric kinetic analysis. Sitting systolic and diastolic blood pressures were recorded at 3 consecutive visits, and the mean was calculated. Clinical data, including demographics and medication, were collected for all recipients. Results were analyzed by the chi-square test and analysis of variance, taking a p value of <0.05 to be significant. RESULTS: A total of 41.7% of the subjects were hypertensive (diastolic blood pressure >90 mm Hg) at the time of the study, with 79.6% taking at least one antihypertensive agent. We found no difference between the number of antihypertensive agents, cyclosporin dose and level, renal function, or systolic blood pressure for the different recipient or donor genotypes. We also found no significant correlation between ACE enzymatic activity and systolic or diastolic blood pressure. CONCLUSIONS: Our study of 211 recipients and 154 corresponding donors is the largest investigation of this polymorphism in a cardiac transplantation population. We found no apparent relationship between the ACE genotype (of either donor or recipient) and systemic hypertension (absolute measurements and the number or dose of antihypertensive agents used). 相似文献
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Hyung Bin Park Mihee Koh Se Hyun Cho Brian Hutchinson Bonghee Lee 《Journal of orthopaedic research》2005,23(6):1419-1424
The anterior cruciate ligament (ACL) serves as the primary restraint to anterior tibial translation. In addition to this biomechanical function, the ACL appears to have a function in neuromuscular control. This hypothesis was formulated after the discovery of mechanoreceptors within the ACL. The full somatosensory pathway from the ACL to the cerebrum has yet to be elucidated. In order to map this sensory pathway, we conducted a viral trans-synaptic tracing experiment using the neurotropic pseudorabies virus (PRV). The pseudorabies virus was injected into the ACL of rats and allowed to replicate and spread trans-synaptically for 6-7 days. The brain and spinal cord of each sacrificed rat was then removed and processed immunohistochemically to detect the presence of PRV. PRV-immunoreactive neurons were found to be localized in several different regions from the spinal cord to the cerebrum. Four nuclei in the reticular formation of the brain stem demonstrated strong positive labeling: the mesencephalic reticular nucleus, magnocellular reticular nucleus, paragigantocellular reticular nucleus, and gigantocellular reticular nucleus. This finding suggests that the nerve endings of the rat ACL project into the cerebrum and that the reticular formation may play an important role in the afferent pathway of those nerve endings. 相似文献
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Picotamide inhibition of excess in vitro thromboxane B2 release by colorectal mucosa in inflammatory bowel disease. 总被引:1,自引:0,他引:1
Collins CE Benson MJ Burnham WR Rampton DS 《Alimentary pharmacology & therapeutics》1996,10(3):315-320
BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease. 相似文献
28.
Anderson RA; Evans LW; Irvine DS; McIntyre MA; Groome NP; Riley SC 《Human reproduction (Oxford, England)》1998,13(12):3319-3325
Follistatin is a binding protein for the activin and inhibin family of
hormones, regulating their biological activity. In the male reproductive
tract, the interaction of these factors is likely to be involved in the
regulation of the proliferation of several cell types. We have investigated
the presence of follistatin and activin A in seminal plasma using specific
immunoassays and have localized follistatin and activin/inhibin subunits in
the adult human testis, prostate and seminal vesicle to establish their
likely sources. High concentrations of immunoreactive follistatin were
present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in
peripheral plasma) and were similar in men with oligo/azoospermia and
following vasectomy. Follistatin immunoreactivity was localized to both
Leydig and Sertoli cells of the testis, and to epithelial cells of the
prostate gland and seminal vesicle, which are likely to be the predominant
sources of the hormone in seminal plasma. Activin A was also present in
seminal plasma in normal men but was undetectable following vasectomy, thus
deriving from the testis. Consistent with this finding, the betaA-subunit
was immunolocalized in Sertoli and Leydig cells but was not present in
seminal vesicle or prostate gland. The functional significance of the high
concentrations of follistatin secreted into seminal plasma by the prostate
gland and/or seminal vesicle is uncertain, but they may regulate the
biological activity of testis-derived activin A and inhibin B.
相似文献
29.
M P de Caestecker B A Telfer I V Hutchinson F W Ballardie 《Journal of immunological methods》1992,154(1):11-20
Two colour flow cytometry was used to analyse in situ cytokine expression by human monocytes. Whole blood was cultured in siliconised glass bottles, with or without E. coli lipopolysaccharide (LPS), for various times, and the mononuclear cells (MNCs) then exposed to a variety of permeabilisation procedures prior to flow cytometric analysis. Paraformaldehyde (PF)/saponin fixation preserved cellular morphology, and caused a reproducible degree of permeabilisation (estimated by propidium iodide inclusion: mean 94%, range 86-99% (n = 33)). After fixation with 4% PF and permeabilisation with 1% saponin at 0 degrees C in PBS containing 20% human serum, MNCs were incubated with phycoerythrin(PE)-conjugated mouse anti-CD14 (monocyte phenotype) and polyclonal rabbit anti-human interleukin-1 alpha (IL-1 alpha), IL-1 beta, tumour necrosis factor alpha (TNF-alpha), or control rabbit IgG. Binding of rabbit antibodies was detected using goat anti-rabbit IgG fluorescein isothiocyanate (FITC). FITC fluorescence was increased in CD14 PE positive cells with the three anti-cytokine antibodies following LPS stimulation, compared with controls. There was a reproducible dose related response in monocyte IL-1 beta and TNF-alpha expression following LPS stimulation, with early peaks in TNF-alpha (2 h), compared with IL-1 beta (4 h), and IL-1 alpha (12 h). Specificity of this cytokine detection system was confirmed by inhibition studies using the corresponding recombinant human cytokines, by an absence of staining in CD14 negative or unpermeabilised MNCs, and by the characteristic cytoplasmic localisation of the different cytokines visualised with UV immunochemistry. Hence, the methods described here provide a reproducible, semiquantitative and specific assay for the detection of cell associated monokines. The technique may be applicable to the analysis of a variety of different cytokines in other phenotypically defined cell populations. 相似文献
30.
The role of major and minor histocompatibility antigens in active enhancement of rat kidney allograft survival by blood transfusion 总被引:1,自引:0,他引:1
Rats given a blood transfusion do not reject a subsequent kidney allograft from the same donor strain. This effect is strain-specific so that pretransplant blood transfusion from a LEW (RT1l) rat will protect a LEW kidney in a DA (RT1a) recipient but not a PVG/c (RT1c) kidney. The same is true in other combinations. Using DA or PVG.RT1a congenic recipients we have shown that sharing of all or part of the MHC or of minor alloantigens by the blood transfusion and kidney transplant donors is sufficient to prolong allograft survival. Activation of suppression against minor alloantigens appears to require two signals: one is the minor alloantigen and the other may be a major histocompatibility complex alloantigen. 相似文献