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Diameter Decreased (diameter + decreased)
Selected AbstractsNeuronal activity-related coupling in cortical arterioles: involvement of astrocyte-derived factorsEXPERIMENTAL PHYSIOLOGY, Issue 1 2005T. A. Lovick Neuronal activity-evoked dilatation was investigated in cortical arterioles in brain slices from mature rats maintained in vitro at 31,33°C. In the presence of the thromboxane A2 agonist U46619 (75 nm) to preconstrict vessels, internal diameter decreased by 14.2% and rhythmic contractile activity (vasomotion) developed. Addition of the epoxygenase inhibitor miconazole (20 ,m) produced a further decrease in diameter and increase in the frequency of vasomotion, suggesting that tonic release of epoxygenase products maintains a level of cerebrovascular dilator tone. Addition of 1 ,m AMPA for 5 min evoked a 15.4 ± 3.7% increase in diameter and the frequency of vasomotion decreased by ,6.7 ± 1.4 contractions min,1. The response persisted in the presence of 1 ,m TTX, indicating that it was independent of neuronal activity and thus likely to have been evoked by activation of AMPA receptors on astrocytes rather than neurones. The response to the brief (5 min) application of AMPA remained unchanged in the presence of miconazole (20 ,m). Prolonged (30 min) application of AMPA produced a +12.1 ± 1.5% increase in internal diameter and reduction in vasomotion (,8.4 ± 1.7 contractions min,1) that were sustained throughout the stimulation period. However, when AMPA was applied in the presence of miconazole (20 ,m) it evoked only a transient increase in diameter (+9.8 ± 3.1%) and decrease in vasomotion (,6.6 ± 1.5 contractions min,1) that lasted for less than 10 min despite continued application of AMPA. The results suggest that products of epoxygenase activity, probably epoxyeicosatrienoic acids (EETs) are involved in activity-related dilatation in cortical arterioles. Whilst epoxygenase activity is not required to initiate dilatation, it appears to be involved in sustaining the response. Thus EETs released from membrane stores could contribute to the initial stages, but once these have been depleted de novo synthesis of EETs is required to maintain the effect. [source] Percutaneous drainage of hydatid cyst of the liver: long-term resultsHPB, Issue 4 2002KY Polat Background Previously surgical operation was the only accepted treatment for hydatid liver cysts. Recently percutaneous management has become more preferable because of its low morbidity rate and lower cost. Patients and methods In all, 101 patients harbouring 120 hydatid cysts of the liver were treated by percutaneous drainage between October 1994 and December 1997. Of these cysts, 89 were in the right liver and 31 in the left liver. Thirty-one patients had had previous operations for hydatid disease. All cysts had an anechoic or hypoechoic unilocular appearance on ultrasound scan. The mean dimension of the cysts was 7.5 ± 2.9 cm (range 3,10.4 cm). All patients received oral albendazole 10 mg/kg perioperatively. After aspiration under sonographic guidance, cysts were irrigated with 95% ethanol. Results The amount of cyst fluid aspirated was 220 ± 75 ml and the amount of irrigation solution used was 175 ± 42 ml. Four patients developed mild fever and three had urticaria. Mean length of hospital stay was 2.1 ± 0.7 (range 1,4) days, and patients were followed up for 43,62 months (mean 54 ± 5.4 months). Maximal cyst diameter decreased from 7.5 ± 2.9 cm to 3.2 ± 15 cm (p<0.001). Sonographic examinations revealed high-level heterogeneous echoes in the cyst cavity (heterogeneous echo pattern), while the cyst cavity was completely obliterated by echogenic material (pseudotumour echo pattern). Discussion Most hydatid cysts of the liver can be managed successfully by acombinationof drugtherapyand percutaneous drainage. [source] Equilibrium studies of protein aggregates and homogeneous nucleation in protein formulationJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 2 2010Sylvia Kiese Abstract Shaking or heat stress may induce protein aggregates. Aggregation behavior of an IgG1 stressed by shaking or heat following static storage at 5 and 25°C was investigated to determine whether protein aggregates exist in equilibrium. Aggregates were detected using different analytical methods including visual inspection, turbidity, light obscuration, size exclusion chromatography, and dynamic light scattering. Significant differences were evident between shaken and heated samples upon storage. Visible and subvisible particles (insoluble aggregates), turbidity and z -average diameter decreased whilst soluble aggregate content increased in shaken samples over time. Insoluble aggregates were considered to be reversible and dissociate into soluble aggregates and both aggregate types existed in equilibrium. Heat-induced aggregates had a denatured protein structure and upon static storage, no significant change in insoluble aggregates content was shown, whilst changes in soluble aggregates content occurred. This suggested that heat-induced insoluble aggregates were irreversible and not in equilibrium with soluble aggregates. Additionally, the aggregation behavior of unstressed IgG1 after spiking with heavily aggregated material (shaken or heat stressed) was studied. The aggregation behavior was not significantly altered, independent of the spiking concentration over time. Thus, neither mechanically stressed native nor temperature-induced denatured aggregates were involved in nucleating or propagating aggregation. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:632,644, 2010 [source] Alkylated poly(styrene-divinylbenzene) monolithic columns for ,-HPLC and CEC separation of phenolic acidsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 17 2007Zdenka Ku, erová Abstract Macroporous poly(styrene-divinylbenzene) monolithic columns were prepared in fused silica capillaries of 100 ,m id by in-situ copolymerization of styrene with divinylbenzene in the presence of propan-1-ol and formamide as the porogen system. The monoliths were subsequently alkylated with linear alkyl C-18 groups via Friedel-Crafts reaction to improve the retention and chromatographic resolution of strongly polar phenolic acids. A new thermally initiated grafting procedure was developed in order to shorten the time of the alkylation process. The grafting procedure was optimized with respect to the reaction temperature, time, the grafting reactant concentration, and the solvent used. The type of solvent and the grafting temperature are the most significant factors affecting the hydrodynamic properties, porosity, and efficiency of the columns. While the equivalent particle diameter of the grafted column increased, the capillary-like flow-through pore diameter decreased in comparison to non-alkylated monoliths. The hydrodynamic permeability of the monolith decreased, but the monolithic column still permitted fast ,-HPLC separations. [source] Crown development in a pioneer tree, Rhus trichocarpa, in relation to the structure and growth of individual branchesNEW PHYTOLOGIST, Issue 4 2006Noriyuki Osada Summary ,,Based on an allometric reconstruction, the structure and biomass-allocation patterns of branches and current-year shoots were investigated in branches of various heights in the pioneer tree Rhus trichocarpa, to evaluate how crown development is achieved and limited in association with height. Path analysis was conducted to explore the effects of light availability, basal height and size of individual branches on branch structure and growth. ,,Branch angle was affected by basal height, whereas branch mass was influenced primarily by light availability. This result suggests that branch structure is strongly constrained by basal height, and that trees mediate such constraints under different light environments. ,,Previous-year leaf area and light availability showed positive effects on current-year stem mass. In contrast, branch basal height and mass negatively affected current-year stem mass. Moreover, the length of stems of a given diameter decreased with increasing branch height. Therefore the cost of biomass investment for a unit growth in length is greater for branches of larger size and at upper positions. ,,Vertical growth rate in length decreased with increasing height. Height-dependent changes in stem allometry and angle influenced the reduction in vertical growth rate to a similar degree. [source] Comparison of the Effect of the Aromatase Inhibitor, Anastrazole, to the Antioestrogen, Tamoxifen Citrate, on Canine Prostate and SemenREPRODUCTION IN DOMESTIC ANIMALS, Issue 2009G Gonzalez Contents This study compared the efficiency of the aromatase inhibitor, anastrazole, with the antioestrogenic receptor blocker, tamoxifen, on normal (NRL) and hyperplastic prostate glands. Forty healthy dogs were classified as NRL (n = 18) or abnormal (ABN) with benign prostate hyperplasia (n = 22). The dogs were randomly assigned to one of the following six groups, treated for 60 days; oral placebo for normal (NRL-PLC; n = 6) and abnormal (ABN-PLC; n = 6), oral anastrazole 0.25,1 mg/day, for normal (NRL-ANZ, n = 6) and abnormal (ABN-ANZ, n = 8) and oral tamoxifen citrate 2.5,10 mg/day for normal (NRL-TMX; n = 6) and abnormal (ABN-TMX; n = 8) dogs. The dogs were evaluated before treatment and then monthly for 4 months. At the end of the treatment, the prostatic volume decreased by 28.5 ± 4.3%, 21.6 ± 6.3% and 0.7 ± 1.0% in the ABN-TMX, ABN-ANZ and ABN-PLC (p < 0.01), respectively. From then on, prostatic volume began to increase without reaching pre-treatment values at the end of the study. In the ABN animals, there were no differences for this parameter between ANZ and TMX treatment (p > 0.1), whereas in the NRL animals ANZ produced a less pronounced decrease (p < 0.05), libido, testicular consistency and scrotal diameter decreased during treatment in the TMX group (p > 0.05). These parameters and sperm volume, count, motility and morphological abnormalities remained unaltered throughout the study in the ANZ and PLC groups (p > 0.05). There were no haematological nor biochemical side effects. Anastrazole might offer a safe and effective alternative for the medical management of dogs with benign prostatic hyperplasia. [source] Ultrastructural changes induced in cutaneous collagen by ultraviolet-A1 and psoralen plus ultraviolet A therapy in systemic sclerosisTHE JOURNAL OF DERMATOLOGY, Issue 2 2008Noriyuki SAKAKIBARA ABSTRACT In the present study, we examined the ultrastructural alterations in collagen fibrils clinically softened by ultraviolet-A1 (UVA1, 340,400 nm) therapy and psoralen plus long-wave ultraviolet (PUVA) therapy and compared collagen fibril diameters in four patients with systemic sclerosis (SSc). In skin sclerosis, the dermis is compacted from the epidermal layer to the sweat glands, and the collagen bundles are thicker with decreased space between them. We obtained skin specimens before and after UVA1 or PUVA therapy, and compared cutaneous alterations in one diffuse-type patient and one limited-type patient following UVA1 therapy, and in two diffuse-type patients following PUVA treatment. Ultramicroscopic analysis revealed that UVA1 treatment decreased the diameter of the broad collagen fibrils, mainly in the upper reticular layer. PUVA induced similar alterations in the collagen fibrils, extending to the upper and middle reticular layers. PUVA therapy induced alterations in collagen fibril diameter in deeper layers than did UVA1 therapy, which might be related to the direct action of UV light and the depth of the light penetration. In three of four patients, collagen fibril diameter decreased, collagen fibril thickness equalized, and new, thin fibrils developed among the collagen fibrils, suggesting that collagen degradation and synthesis underlie the alterations induced by UVA1 and PUVA phototherapies. [source] Vascular and Biology 04BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue S1 2002A.J. Hayes Background: Angiopoietin-1 (Ang-1) functions physiologically to promote angiogenesis by inducing vascular branching and smooth muscle recruitment. However, we have previously reported to this Society that in an experimental breast cancer model, over-expression of Ang-1 led to tumour inhibition and that expression of Ang-1 in clinical breast cancer specimens was infrequent. We now report a morphological analysis of the tumour microvessels in this model in an attempt to ascertain a mechanism for tumour inhibition. Methods: Ang-1 over-expressing and vector-transfected xenograft tumours used in previous tumourigenicity assays were fixed routinely and sectioned. Endothelial cells and smooth muscle cells were immuno-stained with monoclonal antibodies to CD-31 and smooth muscle actin, visualized with confocal fluorescence microscopy and quantitated with image analysis. Tumours were also immuno-stained for markers of proliferation and apoptosis. Results: Ang-1 expressing tumours displayed striking differences in microvascular morphology at the leading edge of the tumour when compared with controls. Although the number of microvessels was not altered, the peripheral vessels in the Ang-1 tumours were much less ectatic than the dilated immature tumour vessels seen in controls. They were surrounded by a closely adherent continuous layer of smooth muscle cells, absent in controls. In these vessels the ratio of smooth muscle cells to endothelial cells was increased threefold (P < 0.01) and luminal diameter decreased twofold (P < 0.05) compared with controls. The rates of tumour cell proliferation and apoptosis were decreased twofold (P < 0.001) compared with controls. Conclusions: Ang-1 over-expression induced stabilization of microvessels at the tumour periphery, which resulted in a decreased rate of tumour growth. [source] Transcatheter closure of perimembranous ventricular septal defects using the amplatzer membranous VSD occluder: Immediate and midterm results of an international registryCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2006Ralf Holzer MD Abstract Objective: To report the immediate and midterm results of transcatheter closure of perimembranous ventricular septal defect (PmVSD) using the Amplatzer membranous VSD occluder (AMVSD). Methods: Between April 2002 and August 2004, 100 patients underwent an attempt of percutaneous device closure of PmVSD using the AMVSD in 24 international centers. The median age was 9.0 years (0.7,58 years) and the median weight was 27.5 kg (7,121 kg). Results: A device was successfully deployed in 93/100 (93%) patients. Reasons for procedural failure were an increased gradient across the left ventricle outflow tract in one patient, aortic regurgitation in 2 patients, and inability to securely position the device in 4 patients. The median VSD size by TEE was 7.0 mm (1.5,13 mm), median device size 10 mm (4,16 mm) and median fluoroscopy time 22.1 min (8.9,96.0 min). Weight below 10 kg (P = 0.0392), inlet extension of the VSD (P = 0.0139) and aortic cusp prolapse into the VSD (P = 0.0084) were significantly associated with a lower procedural success. Patients have been followed up for a median of 182 days (1,763 days). There were no procedure-related deaths. Complications were encountered in 29/100 (29%) patients, including rhythm or conduction anomalies in 13 patients (two with complete heart block requiring permanent pacemaker implantation), new or increased aortic (9 patients) or tricuspid (9 patients) regurgitation, most of which were classified as trivial or mild. Patients with a weight below 10 kg had a significantly higher incidence of adverse events than patients with a weight above 10 kg (58.3% versus 25.0%, P = 0.0285). Immediately after device release complete closure of the defect was present in 54/93 (58.1%) patients, increasing to 46/55 (83.6%) patients at 6-months follow-up (P = 0.0012). Left ventricle end-diastolic diameter decreased from a median of 44 mm prior to device closure to a median of 39 mm at 6-months postprocedure (P = 0.0015). Conclusion: Closure of PmVSDs using the AMVSD occluder is safe and effective. However, longer follow-up period is warranted prior to the wide spread use of this device. © 2006 Wiley-Liss, Inc. [source] Effect of acute postural variation on diabetic macular oedemaACTA OPHTHALMOLOGICA, Issue 2 2010Martin Vinten Abstract. Purpose:, This study aimed to study the pathophysiology of diabetic macular oedema (DMO) by analysis of concomitant changes in macular volume (MV), mean arterial blood pressure (MABP), intraocular pressure (IOP), and retinal artery and vein diameters in response to acute postural changes in patients with DMO and healthy subjects. Methods:, Thirteen patients with DMO (13 eyes) and five healthy subjects (five eyes) were examined after resting in a chair for 15 mins using optical coherence tomography to measure MV and fundus photography to assess retinal vessel diameters. The patients then lay down for 60 mins, during which they were examined repeatedly before they were reseated and examined again. Intraocular pressure was measured using pulse-air tonometry, arterial blood pressure by sphygomanometry and fluid columns using rulers and a spirit level. Results:, In healthy subjects, retinal artery (p = 0.02) and vein (p = 0.001) diameters decreased when subjects lay down, whereas MV remained stable. In patients with DMO, no orthostatic variation in retinal vessel diameters could be demonstrated, whereas MV had increased by 2.4 ± 0.6% (mean ± standard error of the mean; p = 0.006) 50 mins after assuming a recumbent position. In both healthy subjects and DMO patients, MABP decreased and IOP increased in a recumbent position, with no significant difference between the groups. Conclusions: The increase in MV that occurs in DMO when changing from a seated to a recumbent position is associated with a failure of retinal artery contraction, a response seen in healthy subjects that appears to counter-regulate the increase in ocular perfusion pressure caused by assuming a recumbent position. [source] | ||||||||||||||||