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Complete Restoration (complete + restoration)
Selected AbstractsCPU-86017 improves the compromised blood,brain barrier permeability mediated by impaired endothelial no system and oxidative stress caused by L -thyroxineDRUG DEVELOPMENT RESEARCH, Issue 3 2005Rong-Hui Du Abstract Impaired endothelial cell (EC) function leads to alterations in the permeability of the blood,brain barrier (BBB). There are two aspects of the transport through the BBB: from the blood to the brain (influx) and from the brain to the blood (efflux). An impaired EC model induced by L -thyroxine that compromises the influx and efflux properties of the BBB was used to assess responses to the intervention of CPU-86017 (an antioxidant and calcium channel blocker) and propranolol. CPU-86017 (t1/2=1.5 h) was also used as a target drug, leaving no traces in the brain and blood 24 h after administration. The permeability of the BBB was evaluated by using CPU-86017 after iv and icv injection and concentrations in the blood and brain being measured by high-performance liquid chromatography. The bidirectional permeability of CPU-86017 was impaired and associated with a reduced NO bioavailability assessed functionally by the vasoactivity in the model. Partial relief of NO bioavailability and oxidative stress induced by propranolol was consistent with a recovery of BBB efflux alone. Complete recovery in the efflux and influx of the BBB by CPU-86017 was a result of the complete restoration of NO bioavailability and reduction in oxidative stress. Normal BBB influx is dependent on an intact endothelial NO system, and efflux could be restored easily by partial improvement of NO bioavailability. CPU-86017 is thus more effective than propranolol in protecting the endothelium from damage produced by L -thyroxine through oxidative stress. Drug Dev. Res. 64:145,156, 2005. © 2005 Wiley-Liss, Inc. [source] O2 -sensing after carotid chemodenervation: hypoxic ventilatory responsiveness and upregulation of tyrosine hydroxylase mRNA in brainstem catecholaminergic cellsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2000Jean-Christophe Roux Abstract Ventilatory responses to acute and long-term hypoxia are classically triggered by carotid chemoreceptors. The chemosensory inputs are carried within the carotid sinus nerve to the nucleus tractus solitarius and the brainstem respiratory centres. To investigate whether hypoxia acts directly on brainstem neurons or secondarily via carotid body inputs, we tested the ventilatory responses to acute and long-term hypoxia in rats with bilaterally transected carotid sinus nerves and in sham-operated rats. Because brainstem catecholaminergic neurons are part of the chemoreflex pathway, the ventilatory response to hypoxia was studied in association with the expression of tyrosine hydroxylase (TH). TH mRNA levels were assessed in the brainstem by in situ hybridization and hypoxic ventilatory responses were measured in vivo by plethysmography. After long-term hypoxia, TH mRNA levels in the nucleus tractus solitarius and ventrolateral medulla increased similarly in chemodenervated and sham-operated rats. Ventilatory acclimatization to hypoxia developed in chemodenervated rats, but to a lesser extent than in sham-operated rats. Ventilatory response to acute hypoxia, which was initially low in chemodenervated rats, was fully restored within 21 days in long-term hypoxic rats, as well as in normoxic animals which do not overexpress TH. Therefore, activation of brainstem catecholaminergic neurons and ventilatory adjustments to hypoxia occurred independently of carotid chemosensory inputs. O2 -sensing mechanisms unmasked by carotid chemodenervation triggered two ventilatory adjustments: (i) a partial acclimatization to long-term hypoxia associated with TH upregulation; (ii) a complete restoration of acute hypoxic responsivity independent of TH upregulation. [source] Complementation of NADPH oxidase in p67-phox-deficient CGD patientsFEBS JOURNAL, Issue 4 2000p67-phox/p40-phox interaction Chronic granulomatous disease (CGD) is due to a functional defect of the O2, generating NADPH oxidase of phagocytes. Epstein,Barr-virus-immortalized B lymphocytes express all the constituents of oxidase with activity 100 times less than that of neutrophils. As in neutrophils, oxidase activity of Epstein,Barr-virus-immortalized B lymphocytes was shown to be defective in the different forms of CGD; these cells were used as a model for the complementation studies of two p67-phox-deficient CGD patients. Reconstitution of oxidase activity was performed in vitro by using a heterologous cell-free assay consisting of membrane-suspended or solubilized and purified cytochrome b558 that was associated with cytosol or with the isolated cytosolic-activating factors (p67-phox, p47-phox, p40-phox) from healthy or CGD patients. In p67-phox-deficient CGD patients, two cytosolic factors are deficient or missing: p67-phox and p40-phox. Not more than 20% of oxidase activity was recovered by complementing the cytosol of p67-phox-deficient patients with recombinant p67-phox. On the contrary, a complete restoration of oxidase activity was observed when, instead of cytosol, the cytosolic factors were added in the cell-free assay after isolation in combination with cytochrome b558 purified from neutrophil membrane. Moreover, the simultaneous addition of recombinant p67-phox and recombinant p40-phox reversed the previous complementation in a p40-phox dose-dependent process. These results suggest that in the reconstitution of oxidase activity, p67-phox is the limiting factor; the efficiency of complementation depends on the membrane tissue and the cytosolic environment. In vitro, the transition from the resting to the activated state of oxidase, which results from assembling, requires the dissociation of p40-phox from p67-phox for efficient oxidase activity. In the process, p40-phox could function as a negative regulatory factor and stabilize the resting state. [source] Phototunable Azobenzene Cholesteric Liquid Crystals with 2000 nm RangeADVANCED FUNCTIONAL MATERIALS, Issue 21 2009Timothy J. White Abstract Phototuning of more than 2000,nm is demonstrated in an azobenzene-based cholesteric liquid crystal (azo-CLC) consisting of a high-helical-twisting-power, axially chiral bis(azo) molecule (QL76). Phototuning range and rate are compared as a function of chiral dopant concentration, light intensity, and thickness. CLCs composed of QL76 maintain the CLC phase regardless of intensity or duration of exposure. The time necessary for the complete restoration of the original spectral properties (position, bandwidth, baseline transmission, and reflectivity) of QL76-based CLC is dramatically reduced from days to a few minutes by polymer stabilization of the CLC helix. [source] The legal construction of the social security system of the Republic of KosovoINTERNATIONAL SOCIAL SECURITY REVIEW, Issue 1 2009Ma Lourdes Arastey Sahún Abstract Following the international community's unsuccessful attempts to broker an agreement between Serbia and Kosovo, the territory of Kosovo controversially declared independence on 17 February 2008. This article provides a description and analysis of the social protection system immediately after the declaration of independence. In the aftermath of conflict, and faced by enormous economic difficulties, Kosovo's society could not expect a complete restoration of the social security system. To date, the United Nations Mission has committed itself to building a minimum legal framework, seeking to give answers to main and essential challenges. But the core structure of the social security system is yet to be laid. Nonetheless, in a complex situation such as that of Kosovo, the realization of a social protection framework must be seen as an essential mechanism for reconstruction and peacekeeping. [source] An Overview of Complete Artificial Fixed Dentition Supported by Endosseous ImplantsARTIFICIAL ORGANS, Issue 1 2005Dennis Flanagan Abstract:, The construction of a complete restoration of the dentition by the surgical placement of endosseous titanium implants that support a fixed prosthesis in each jaw is possible. The positionings of the implants and teeth in the prostheses are important factors for a successful long-term result. Distribution of the occlusal biting forces over as many implants as possible is important. Off-axial occlusal biting forces should be diverted to the anterior jaws where the forces are not as great. The posterior teeth should be designed with flat occlusal surfaces that separate during excursionary mandibular chewing movements. Medial mandibular flexure caused by the contraction of the medial pterygoid muscle can be addressed by constructing the prosthesis in segments, so as not to have a rigid entity encased in flexing bone that may induce stress in the bone, potentially leading to loss of implant integration and failure. Segmenting also ensures an appropriate fit of the prosthesis with respect to casting and porcelain firing distortion. Lip support by means of a flange in the prosthesis may be necessary when there has been a large amount of bone loss from edentulous resorption. Cleaning and routine maintenance of the prostheses every 3,6 months is essential. [source] Rectal washout with cytotoxic solution can be extended to the whole colonBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 12 2002P. P. Mariani Background: Rectal irrigation with a cytotoxic agent does not kill viable intraluminal cancer cells proximal to the primary tumour. To prevent implantation of these cells at the time of restorative proctectomy, the feasibility of retrograde whole-colon irrigation just before surgery was explored. Methods: The cytotoxic efficacy of different combinations of povidone,iodine (PVPI) and Gastrografin was tested with the trypan blue exclusion test on a human colon carcinoma cell line (SW620) in vitro. Subsequently, a retrograde whole-colon lavage with PVPI 5 per cent and Gastrografin 12 per cent was performed in 14 euthyroid, non-allergic patients with colorectal cancer using a colostomy irrigation set. Thyroid function and mucosal damage were assessed. Results: It took 2 min and approximately 1 litre of infused solution to reach the caecum in all patients. The solution was 100 per cent tumoricidal in vitro and remained so after colonic irrigation. Total serum tri-iodothyronine (T3) levels decreased and those of reverse T3 increased, but normalized after 1 week. Superficial epithelial desquamation was observed shortly after irrigation; however, complete restoration occurred within 7 days. Conclusion: A rectal washout can easily be extended to a retrograde irrigation of the whole colon in elective colorectal cancer surgery. This may help to prevent anastomotic and local recurrence due to implantation of viable exfoliated tumour cells. © 2002 British Journal of Surgery Society Ltd [source] | ||||||||||