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11.
Summary Uridine 5-triphosphate- (UTP-) and adenosine 5-triphosphate-(ATP) induced vasoconstriction was studied in the rabbit basilar artery. The arteries were incubated and perfused at a constant rate of flow. Vasoconstriction was measured as an increase in perfusion pressure.Serotonin, histamine and noradrenaline caused concentration-dependent vasoconstriction, with potency decreasing in that order. Of the nucleotides tested, UTP, UDP, UMP, CTP, ATP, ADP, adenosine 5-O-(3-thio)triphosphate (ATPS), and ,-imido adenosine 5-triphosphate (AMP-PNP) elicited concentration-dependent vasoconstriction, whereas AMP, 2-methylthio-ATP, , -methylene-ATP and ,-methylene-ATP up to 10–3 mol/l caused no or only a very small increase in perfusion pressure. The order of potency of the pyrimidine nucleotides was: UTP = UDP UMP = CTP; that of the purine nucleotides was: ATPS > AMP-PNP > ATP > ADP > 2-methylthio-ATP = , -methylene-ATP = ,-methylene-ATP. The vasoconstrictor effects of UTP and ATP were not or only to a minor degree influenced by: phentolamine; a mixture of atropine, diphenhydramine and methysergide; indometacin; nordihydroguaiaretic acid; denervation by 6-hydroxydopamine; or mechanical removal of endothelium. Prolonged exposure to ,-methylene-ATP elicited only a very small vasoconstriction and did not change the constrictor effects of UTP or ATP. Prolonged exposure to ATPS elicited marked vasoconstriction; subsequently, responses to ATP were reduced whereas those to UTP were, if anything, slightly enhanced. Reactive blue 2 reduced neither the UTP- nor the ATP-induced vasoconstriction. ATP 10–3 mol/l elicited marked additional vasoconstriction after precontraction with UTP 10–3 mol/l, whereas UTP elicited only a very small additional vasoconstriction when its concentration was doubled from 10–3 to 2 × 10–3 mol/l.It is concluded that, in the rabbit basilar artery, the vasoconstrictor response to UTP is mediated by a pyrimidine nucleotide receptor which is distinct from the P2-purinoceptor, and that the vasoconstrictor response to ATP is mediated by a P2-receptor which is distinct from the known P2-subtypes.Send offprint requests to I. v. Kügelgen at the above address 相似文献
12.
Clemens Allgaier Henning Wellmann Angelika Schobert Gerhart Kurz Ivar von Kügelgen 《Naunyn-Schmiedeberg's archives of pharmacology》1995,352(1):25-30
The ATP-induced increase in tritium outflow from cultured chick sympathetic neurons prelabelled with [3H]-noradrenaline was investigated.Seven days-old dissociated cell cultures of embryonic paravertebral ganglia, loaded with [3H]-noradrenaline (0.05 M), were superfused in the presence of (+)-oxaprotiline and exposed to ATP, ATP-analogues, or 1,1-dimethyl-4-piperazinium (DMPP) for 2 min. ATP (3 LM-3 mM), 2-methylthio-ATP (3–100 M), as well as DMPP (10 and 100 M) induced a significant overflow of tritium. The EC50-value of ATP was 20 M. Both the ATP-induced and the DMPP-induced tritium overflow was Ca2+-dependent and sensitive to tetrodotoxin (0.3 M) and -conotoxin (0.1 M); in addition, it was inhibited by the 2-adrenoceptor agonist 5-bromo-6-(2-imidazoline-2-ylamino)-quinoxaline (UK-14,304; 1 M). The effects of ATP and DMPP were not additive. The ATP-induced as well as the DMPP-induced overflow of tritium was diminished by the P2-purinoceptor antagonists suramin (300 M) and reactive blue 2 (3 M); in all 4 cases, the inhibition amouted to approximately 40%. The tritium overflow induced by ATP or DMPP was almost abolished by the nicotinic receptor antagonist mecamylamine (10 M) and markedly inhibited by hexamethonium (100 M). Neither ATP nor electrical stimulation caused an overflow of tritium from cultures loaded with [3H]-choline.The results suggest that ATP at molar concentrations induces noradrenaline release from cultured chick sympathetic neurons via an action on a subclass of the nicotinic cholinoceptor. 相似文献
13.
78 rats weighing 180–200 g were used to assess the bone tissue responses to three periodontal dressings (Coe-pak, Peripac and Ward's Wondrpak). The dressings were implanted subscutaneously on periosteal covered and denuded bone. Sham operated animals served as controls and a comparison btween the responses produced by the three dressngs were made.
In one series the dressings remained in situ for 3, 7, 14, 30 and 90 days. Osteocyte damage of varying extent was recorded for all materials. Remodelling of the bone surface adjacent to the dressing was observed. Bone resorption was never foud in the gournd defect produced to denude the bone tissue, but repair of the defect by bone formation was observed after long observation periods. This repair was retarded in some animals were Ward's Wondrpak had been implanted.
In another seiries Ward's Waondrpak was implanted against bone for three days, then re-operated to remove the dressing and the defect allowed to heal for 30 days. The test group exhibited empty bone lacunae and the repair of the defect was retarded or lacking. 相似文献
In one series the dressings remained in situ for 3, 7, 14, 30 and 90 days. Osteocyte damage of varying extent was recorded for all materials. Remodelling of the bone surface adjacent to the dressing was observed. Bone resorption was never foud in the gournd defect produced to denude the bone tissue, but repair of the defect by bone formation was observed after long observation periods. This repair was retarded in some animals were Ward's Wondrpak had been implanted.
In another seiries Ward's Waondrpak was implanted against bone for three days, then re-operated to remove the dressing and the defect allowed to heal for 30 days. The test group exhibited empty bone lacunae and the repair of the defect was retarded or lacking. 相似文献
14.
Christoffer Bugge Erik Magnus Sæther Odd Terje Brustugun Ivar Sønbø Kristiansen 《Health policy (Amsterdam, Netherlands)》2021,125(8):1100-1107
BackgroundThe broader cost consequences of diseases may be of interest for a wide range of stakeholders. We aimed to estimate all relevant societal costs of cancer and to provide insight into the relative magnitude of the different cost categories.MethodWe used data from eight different health and work-related registries in Norway. Direct, indirect, and intangible costs (value of lost life years) were estimated over a period of one year with a combination of a top-down and a bottom-up costing approach.ResultsThe indirect costs (EUR 1,997 million per year) are almost as high as direct costs (EUR 2,154 million), and the value of lost life years and quality of life represents the greatest cost related to cancer (EUR 18,200 million). In addition, cancer is associated with other costs which are commonly omitted from cost-of-illness analyses, including informal nursing (EUR 306 million), patient time costs (EUR 85 million), and excess costs of using public funds (EUR 439 million). Breast and cervical cancer had relatively high work absenteeism costs, while pancreatic and lung cancer had relatively high production costs due to premature deaths.DiscussionDirect health care costs represent small proportions of the total societal costs of cancer. Costs commonly omitted in cost-of-illness analyses represent a significant cost and should be measured and valued in these analyses. 相似文献
15.
Höök H Ekegren MB Ericsson H Vågsholm I Danielsson-Tham ML 《Scandinavian journal of infectious diseases》2004,36(6-7):435-442
84 Campylobacter jejuni isolates from Swedish patients with domestic infection were characterized with pulsed-field gel electrophoresis (PFGE), and the subtype information considered in relation to epidemiological data. Based on pattern combinations from restriction cleavage with SmaI and SalI, 52 different PFGE types were identified. Types with an average pattern similarity of at least 82% and 63% were assembled in groups and clusters, respectively. The 2 largest clusters included 71% of the isolates. The distribution in time varied between different groups and clusters, where some were isolated sporadically during the whole period and others appeared more concentrated in time. Types in 1 cluster were significantly more often isolated in summer than other types in the study. Isolates from children showed lower pattern similarity to other isolates than isolates from adults. Sets of type and time related cases, possibly representing small outbreaks, were identified when indistinguishable PFGE patterns were found in isolates from temporally related cases. Our results indicate that although a large number of genotypes may be found among C. jejuni strains infecting humans, a large proportion of these may be genetically related, and that different genotypes may appear during different seasons and infect individuals of different ages. 相似文献
16.
Omdal R Waterloo K Koldingsnes W Husby G Mellgren SI 《The Journal of rheumatology》2003,30(2):283-287
OBJECTIVE: Studies to prove a relationship between fatigue and immunological, inflammatory, or other disease characteristics of systemic lupus erythematosus (SLE) have shown no consistent findings. To further elucidate the basis for fatigue in SLE, we examined the affective states, personality traits, and mental health status in an unselected group of patients with SLE. METHODS: Fifty-seven Caucasian patients with SLE were examined. Fatigue was measured by the Fatigue Severity Scale. Personality traits and psychological function were evaluated by the Minnesota Multiphasic Personality Inventory-2 (MMPI-2), the affective states by Beck Depression Inventory, and mental health status by the General Health Questionnaire version 30 (GHQ-30). RESULTS: Fatigue was closely associated with high scores on subscales Depression (D-2) and Hysteria (Hy-3) on MMPI-2 (R2 = 0.31; p = 0.0002), as well as with high scores on BDI (R2 = 0.22; p = 0.0006) and GHQ (R2 = 0.33; p < 0.0001). CONCLUSION: Fatigue does not seem to be caused by any easily recognizable single or multiple factor(s) of an inflammatory or immunological state. Our results point to fatigue being a multifaceted phenomenon where several psychosocial factors are strongly related, and indicate that fatigue is part of a complex response to chronic disease. 相似文献
17.
Elisabeth Iversen Erik J. S. Packer Synne M. Sandberg Øyvind Bleie Per Ivar Hoff Peter Schuster 《Journal of interventional cardiac electrophysiology》2018,53(3):309-315
Purpose
Symptomatic severe pulmonary vein stenosis (PVS) after catheter ablation of atrial fibrillation (AF) is a rare but well-recognized complication. Treatment options include pulmonary vein angioplasty with or without drug eluting balloons or angioplasty with stent implantation. The treatment of choice is unclear. In our center, pulmonary vein stenting is the treatment of choice for significantly stenotic veins. We present the long-term clinical outcome of 9 patients treated with stent implantation.Methods
Between 2001 and 2015, 3048 patients with AF were treated with catheter ablation at our institution, of which 9 developed symptomatic PVS. A total of 11 PVS were treated. Pre-procedural imaging (CT, MR, transesophageal echocardiography, angiography) was performed in all patients.Results
Mean time from ablation to stenting was 18 months. Three patients had recurrent pneumonia and the remaining reduced functional capacity (NYHA 2). All patients were in functional capacity NYHA 1 (p?<?0.05) after a mean follow-up of 64 (18–132) months. Three patients still had paroxysmal AF, of which two have undergone repeated ablation.Conclusions
Symptomatic PVS after AF ablation can be successfully treated by stent implantation with durable results and good clinical outcome. AF ablation is still a feasible option after stent deployment.18.
Øystein Sørdal Gunnar Qvigstad Ivar Skjåk Nordrum Arne K. Sandvik Bjørn I. Gustafsson Helge Waldum 《Experimental and molecular pathology》2014
Purpose
The purpose of this study is to assess the exocrine and neuroendocrine properties of tumour cells in diffuse gastric cancer with signet ring cell differentiation.Material and methods
Mucin mRNA and protein expressions (MUC1, 2, 3, 4, 5AC, 6 and MUC13) were assessed by immunohistochemistry and in situ hybridization. The neuroendocrine properties were evaluated by protein and mRNA expression of the general neuroendocrine markers chromogranin A and synaptophysin.Results
No MUC expression was observed in signet ring tumour cells including the amorphous substance in any of the nine cases. All cases showed immunoreactivity to synaptophysin, and seven out of nine cases immunoreactivity to chromogranin A in signet ring and non-signet ring tumour cells. Chromogranin A mRNA expression was observed in tumour cells in all samples with retained mRNA.Conclusions
The lack of MUC protein and mRNA in signet ring tumour cells suggests the amorphous substance is not mucin. The lack of MUC mRNA expression in non-signet ring tumour cells questions exocrine differentiation in this tumour group. The abundant protein expression of the general neuroendocrine markers CgA and synaptophysin, and mRNA expression in tumour cells strengthens the hypothesis that this tumour group may be of neuroendocrine origin. 相似文献19.
Hans Sundberg Ingegerd Mejàre Ivar Espelid Anne Björg Tveit 《Acta odontologica Scandinavica》2013,71(3):135-141
This study aimed at mapping the preparation techniques and restorative materials that Swedish dentists are using for primary approximal and occlusal carious lesions. It involved sending a pre-coded questionnaire to a random sample of 923 dentists, with eight items concerning approximal and occlusal restorative preparation techniques and dental materials. Responses were received from 651 (70.5%) dentists. To restore a primary approximal carious lesion in an adolescent with low caries activity and good oral hygiene, the tunnel preparation was chosen by 48% of the dentists, the saucer-shaped preparation by 32%, and the traditional Class II preparation by 20%. The most common preparation technique for restoring an occlusal carious lesion was removal of the carious part only, which was chosen by 74% of the dentists. For a lower second molar with a minor occlusal caries lesion combined with a suspected dentin lesion as judged radiographically, about half of the dentists chose to restore the carious part only and 27% would seal the rest of the fissure system in addition. For a similar lesion with no obvious radiolucency in the dentin, about 1/3 chose the 'no treatment' alternative, 1/3 fluoride treatment, and the rest fissure sealing or other techniques. Composite was used most often and amalgam least often for both approximal and occlusal carious lesions. 相似文献
20.
Sven-Petter Haugvik Irina Pavlik Marangos Bård Ingvald Røsok Ewa Pomianowska Ivar Prydz Gladhaug Øystein Mathisen Bjørn Edwin 《World journal of surgery》2013,37(3):582-590