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1.
In. The University of the West Indies, Faculty of Medical Sciences. Faculty of Medical Sciences, Research Day. St. Augustine, Caribbean Medical Journal, March 21, 2019. .
Não convencional em Inglês | MedCarib | ID: biblio-1006401

RESUMO

Objective: To ascertain the knowledge levels, attitudes and beliefs towards organ donation by relatives of patients in the Intensive Care Unit at two tertiary care hospitals in Trinidad. Design and Methodology: A descriptive study in which researchers'-designed and pretested self-administered questionnaire was used on a sample of 133 randomly selected patients' relatives from two main intensive care hospital units in Trinidad. The respondents were requested to give their consent after necessary ethical approval was received. Data entry was done manually but the analysis was done with the SPSS version 12 programme. Results were presented as frequencies. Results: Demographic characteristics indicated that most were females, of African ethnicity, and Christianity as their main religion. The majority of participants had a high level of knowledge (69.2%) while 57.9% of them had unfavourable attitude towards organ donation. Most (86.5%) had positive belief. It also showed that the respondents' knowledge towards organ donation is significantly related to their age and religion, (P≤, 0.05) while their attitudes are significantly related to their gender and ethnicity (p≤0.05). Their belief was only significantly associated with their marital status. Conclusion: The study has shown that although patients' relatives in Trinidad have general knowledge of organ donation, as well positive belief towards the practice, their attitudes are mostly unfavourable. We believe that their attitude more than their knowledge and beliefs account more for their actions towards organ donation.


Assuntos
Humanos , Masculino , Feminino , Obtenção de Tecidos e Órgãos , Trinidad e Tobago
2.
Rev Sci Instrum ; 87(2): 02A727, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26931945

RESUMO

Ion species ratio of high current positive hydrogen/deuterium ion beams extracted from an electron-cyclotron-resonance ion source for International Fusion Materials Irradiation Facility accelerator was measured by the Doppler shift Balmer-α line spectroscopy. The proton (H(+)) ratio at the middle of the low energy beam transport reached 80% at the hydrogen ion beam extraction of 100 keV/160 mA and the deuteron (D(+)) ratio reached 75% at the deuterium ion beam extraction of 100 keV/113 mA. It is found that the H(+) ratio measured by the spectroscopy gives lower than that derived from the phase-space diagram measured by an Allison scanner type emittance monitor. The H(+)/D(+) ratio estimated by the emittance monitor was more than 90% at those extraction currents.

3.
Rev Sci Instrum ; 87(2): 02A739, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26931957

RESUMO

The objective of linear IFMIF prototype accelerator is to demonstrate 125 mA/CW deuterium ion beam acceleration up to 9 MeV. The injector has been developed in CEA Saclay and already demonstrated 140 mA/100 keV deuterium beam [R. Gobin et al., Rev. Sci. Instrum. 85, 02A918 (2014)]. The injector was disassembled and delivered to the International Fusion Energy Research Center in Rokkasho, Japan. After reassembling the injector, commissioning has started in 2014. Up to now, 100 keV/120 mA/CW hydrogen and 100 keV/90 mA/CW deuterium ion beams have been produced stably from a 10 mm diameter extraction aperture with a low beam emittance of 0.21 π mm mrad (rms, normalized). Neutron production by D-D reaction up to 2.4 × 10(9) n/s has been observed in the deuterium operation.

4.
Rev Sci Instrum ; 85(2): 02A713, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593447

RESUMO

To avoid saturation, beam current transformers must be shielded from solenoid, quad, and RFQ high stray fields. Good understanding of field distribution, shielding materials, and techniques is required. Space availability imposes compact shields along the beam pipe. This paper describes compact effective concatenated magnetic shields for IFMIF-EVEDA LIPAc LEBT and MEBT and for FAIR Proton Linac injector. They protect the ACCT Current Transformers beyond 37 mT radial external fields. Measurements made at Saclay on the SILHI source are presented.

5.
Rev Sci Instrum ; 85(2): 02A918, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593497

RESUMO

In the framework of the ITER broader approach, the International Fusion Materials Irradiation Facility (IFMIF) deuteron accelerator (2 × 125 mA at 40 MeV) is an irradiation tool dedicated to high neutron flux production for future nuclear plant material studies. During the validation phase, the Linear IFMIF Prototype Accelerator (LIPAc) machine will be tested on the Rokkasho site in Japan. This demonstrator aims to produce 125 mA/9 MeV deuteron beam. Involved in the LIPAc project for several years, specialists from CEA/Saclay designed the injector based on a SILHI type ECR source operating at 2.45 GHz and a 2 solenoid low energy beam line to produce such high intensity beam. The whole injector, equipped with its dedicated diagnostics, has been then installed and tested on the Saclay site. Before shipment from Europe to Japan, acceptance tests have been performed in November 2012 with 100 keV deuteron beam and intensity as high as 140 mA in continuous and pulsed mode. In this paper, the emittance measurements done for different duty cycles and different beam intensities will be presented as well as beam species fraction analysis. Then the reinstallation in Japan and commissioning plan on site will be reported.

6.
Rev Sci Instrum ; 85(2): 02A939, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593518

RESUMO

During the past two years, a new ECR 2.45 GHz type ion source has been developed especially dedicated to intense light ion injector project like IPHI (Injecteur Proton Haute Intensité), IFMIF (International Fusion Materials Irradiation Facility), to reduce beam emittance at RFQ entrance by shortening the length of the LEBT. This new ALISES concept (Advanced Light Ion Source Extraction System) is based on the use of an additional LEBT short length solenoid very close to the extraction aperture. The fringe field of this new solenoid produces the needed magnetic field to create the ECR resonance in the plasma chamber. Such geometry allows first putting the solenoid at ground potential, while saving space in front of the extraction to move the first LEBT solenoid closer and focus earlier the intense extracted beam. During the commissioning of the source in 2011-2012, ALISES has produced about 20 mA extracted from a 6 mm diameter plasma extraction hole at 23 kV. But the magnetic configuration combined to the new extraction system geometry led to important Penning discharge conditions in the accelerator column. Lots of them have been eliminated by inserting glass pieces between electrodes to modify equipotential lines with unfavorable ExB vacuum zones where particles were produced and trapped. To study Penning discharge location, several 3D calculations have been performed with OPERA-3D/TOSCA code to simulate the possible production and trapping of electrons in the extraction system. The results obtained on different sources already built have shown very good agreement with sparks location observed experimentally on electrodes. The simulations results as well as experimental measurements are presented and solutions to prevent possible Penning discharge in future source geometries are established.

7.
Rev Sci Instrum ; 83(5): 056109, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22667673

RESUMO

The high intensity ion source (SILHI), in operation at CEA-Saclay, has been used to produce a 90 mA pulsed proton beam with pulse length and repetition rates suitable for the European Spallation Source (ESS) linac. Typical r-r(') rms normalized emittance values smaller than 0.2π mm mrad have been measured for operation in pulsed mode (0.01 < duty cycle < 0.15 and 1 ms < pulse duration < 10 ms) that are relevant for the design update of the Linac to be used at the ESS in Lund.

8.
Rev Sci Instrum ; 83(2): 02A307, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22380154

RESUMO

One of the main goal of intense light ion injector projects such as IPHI, IFMIF, or SPIRAL2, is to produce high current beams while keeping transverse emittance as low as possible. To prevent emittance growth induced in a dual solenoid low energy transfer line, its length has to be minimized. This can be performed with the advanced light ion source extraction system concept that we are developing: a new ECR 2.45 GHz type ion source based on the use of an additional low energy beam transport (LEBT) short length solenoid close to the extraction aperture to create the resonance in the plasma chamber. The geometry of the source has been considerably modified to allow easy maintenance of each component and to save space in front of the extraction. The source aims to be very flexible and to be able to extract high current ion beams at energy up to 100 kV. A specific experimental setup for this source is under installation on the BETSI test bench, to compare its performances with sources developed up to now in the laboratory, such as SILHI, IFMIF, or SPIRAL2 ECR sources. This original extraction source concept is presented, as well as electromagnetic simulations with OPERA-2D code. Ion beam extraction in space charge compensation regime with AXCEL, and beam dynamics simulation with SOLMAXP codes show the beam quality improvement at the end of the LEBT.

9.
Rev Sci Instrum ; 83(2): 02A316, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22380163

RESUMO

The production of rare radioactive ion beam (RIB) far from the valley of stability is one of the final purposes of the Spiral2 facility in Caen. The RIB will be produced by impinging a deuteron beam onto a carbon sample to produce a high neutron flux, which will interact with a uranium target. The primary deuteron beam is produced by an ion source based on ECR plasma generation. The deuteron source and the low energy beam transport (LEBT) has been assembled and tested at CEA Saclay. Diagnostics from other laboratories were implemented on the LEBT in order to characterize the deuteron beam produced and compare it to the initial simulations. The ion source has been based on a SILHI-type source, which has demonstrated good performances in pulsed and continuous mode, and also a very good reliability on long term operation. The 5 mA of deuteron beam required at the RFQ entrance is extracted from the plasma source at the energy of 40 kV. After a brief description of the experimental set-up, this article reports on the first beam characterization experiments.

10.
Rev Sci Instrum ; 83(2): 02A345, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22380192

RESUMO

In the framework of the IFMIF-EVEDA project (International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities), CEA∕IRFU is in charge of the design, construction, and characterization of the 140 mA continuous deuteron injector, including the source and the low energy beam line. The electron cyclotron resonance ion source which operates at 2.45 GHz is associated with a 4-electrode extraction system in order to minimize beam divergence at the source exit. Krypton gas injection is foreseen in the 2-solenoid low energy beam line. Such Kr injection will allow reaching a high level of space charge compensation in order to improve the beam matching at the radio frequency quadrupole (RFQ) entrance. The injector construction is now completed on the Saclay site and the first plasma and beam production has been produced in May 2011. This installation will be tested with proton and deuteron beams either in pulsed or continuous mode at Saclay before shipping to Japan. In this paper, after a brief description of the installation, the preliminary results obtained with hydrogen gas injection into the plasma chamber will be reported.

11.
Rev Sci Instrum ; 83(2): 02B320, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22380299

RESUMO

Over the last few years, the interest of the international scientific community for high power accelerators in the megawatt range has been increasing. For such machines, the ion source has to deliver a beam intensity that ranges from several tens up to a hundred of mA. One of the major challenges is to extract and transport the beam while minimizing the emittance growth and optimizing its injection into the radio frequency quadrupole. Consequently, it is crucial to perform precise simulations and cautious design of the low energy beam transport (LEBT) line. In particular, the beam dynamics calculations have to take into account not only the space charge effects but also the space charge compensation of the beam induced by ionization of the residual gas. The physical phenomena occurring in a high intensity LEBT and their possible effects on the beam are presented, with a particular emphasis on space charge compensation. Then, beam transport issues in different kind of LEBTs are briefly reviewed. The SOLMAXP particle-in-cell code dedicated to the modeling of the transport of charge particles under a space charge compensation regime is described. Finally, beam dynamics simulations results obtained with SOLMAXP are presented in the case of international fusion materials irradiation facility injector.

12.
Lancet ; 375(9733): 2215-22, 2010 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-20609967

RESUMO

BACKGROUND: Uncertainties persist about the magnitude of associations of diabetes mellitus and fasting glucose concentration with risk of coronary heart disease and major stroke subtypes. We aimed to quantify these associations for a wide range of circumstances. METHODS: We undertook a meta-analysis of individual records of diabetes, fasting blood glucose concentration, and other risk factors in people without initial vascular disease from studies in the Emerging Risk Factors Collaboration. We combined within-study regressions that were adjusted for age, sex, smoking, systolic blood pressure, and body-mass index to calculate hazard ratios (HRs) for vascular disease. FINDINGS: Analyses included data for 698 782 people (52 765 non-fatal or fatal vascular outcomes; 8.49 million person-years at risk) from 102 prospective studies. Adjusted HRs with diabetes were: 2.00 (95% CI 1.83-2.19) for coronary heart disease; 2.27 (1.95-2.65) for ischaemic stroke; 1.56 (1.19-2.05) for haemorrhagic stroke; 1.84 (1.59-2.13) for unclassified stroke; and 1.73 (1.51-1.98) for the aggregate of other vascular deaths. HRs did not change appreciably after further adjustment for lipid, inflammatory, or renal markers. HRs for coronary heart disease were higher in women than in men, at 40-59 years than at 70 years and older, and with fatal than with non-fatal disease. At an adult population-wide prevalence of 10%, diabetes was estimated to account for 11% (10-12%) of vascular deaths. Fasting blood glucose concentration was non-linearly related to vascular risk, with no significant associations between 3.90 mmol/L and 5.59 mmol/L. Compared with fasting blood glucose concentrations of 3.90-5.59 mmol/L, HRs for coronary heart disease were: 1.07 (0.97-1.18) for lower than 3.90 mmol/L; 1.11 (1.04-1.18) for 5.60-6.09 mmol/L; and 1.17 (1.08-1.26) for 6.10-6.99 mmol/L. In people without a history of diabetes, information about fasting blood glucose concentration or impaired fasting glucose status did not significantly improve metrics of vascular disease prediction when added to information about several conventional risk factors. INTERPRETATION: Diabetes confers about a two-fold excess risk for a wide range of vascular diseases, independently from other conventional risk factors. In people without diabetes, fasting blood glucose concentration is modestly and non-linearly associated with risk of vascular disease. FUNDING: British Heart Foundation, UK Medical Research Council, and Pfizer.


Assuntos
Glicemia/análise , Doença das Coronárias/etiologia , Complicações do Diabetes , Diabetes Mellitus/sangue , Acidente Vascular Cerebral/etiologia , Adulto , Idoso , Complicações do Diabetes/sangue , Jejum , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
13.
Rev Sci Instrum ; 81(2): 02B301, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20192424

RESUMO

In the framework of the International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities (IFMIF-EVEDA) project, CEA/IRFU is in charge of the design and realization of the 140 mA cw deuteron Injector. The electron cyclotron resonance ion source operates at 2.45 GHz and a 4 electrode extraction system has been chosen. A 2 solenoid beam line, together with a high space charge compensation have been optimized for a proper beam injection in the 175 MHz radio frequency quadrupole. The injector will be tested with proton and deuteron beam production either in pulsed mode or in cw mode on the CEA-Saclay site before to be shipped to Japan. Special attention was paid to neutron emission due to (d,D) reaction. In this paper, the general IFMIF Injector design is reported, pointing out beam dynamics, radioprotection, diagnostics, and mechanical aspects.

14.
Rev Sci Instrum ; 79(2 Pt 2): 02B303, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18315169

RESUMO

In the framework of the IFMIF-EVEDA phase (International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities), the CEA-Saclay is in charged of the design and realization of the 140 mA cw deuteron source. The IFMIF EVEDA demonstrator will be installed in Japan in the next six years and will have to accelerate the deuteron beam up to 9 MeV. CEA will build the source and the low energy beam line (LEBT) and will test the cw high intensity deuteron production at Saclay. The SILHI source is an electron cyclotron resonance (ECR) source, operating at 2.45 GHz. In 2001, it produced more than 130 mA of deuteron beam in pulsed mode to minimize neutron production. Such a result pushes to develop a new ECR source based on the SILHI design and equipped with a specific extraction system. Several options of the accelerator column will be implemented in order to improve the reliability and the efficiency of the source. The IFMIF source and LEBT design will be reported.

15.
Rev Sci Instrum ; 79(2 Pt 2): 02B710, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18315201

RESUMO

In the framework of several International HPPA projects (such as IFMIF, IPHI, and Spiral2) the CEA handles the design and the developments of several electron cyclotron resonance (ECR) ion sources. For the IFMIF EVEDA demonstrator, a 140 mA cw extracted deuteron beam will be required for high yield of neutron production. For radioactive ion production in the Spiral2 project, several milliamperes of deuterons will be delivered with a permanent magnet source. The optimization of the beam quality at the entrance of the radio frequency quadropole (RFQ) accelerator system triggered the need of a new test bench for ion source optimization and beam qualification. The BETSI ion source test bench will operate up to 50 kV and ignite cw or pulsed hydrogen plasma with a 2.45 GHz magnetron. Great care has already been taken to design electrostatic optics of the extraction system to minimize the emittance growth. Plasma diagnostics will be inserted in the source chamber and several beam diagnostics (emittance and current measurements, beam species analysis) will also be implemented on the low energy beam line transport (LEBT). These diagnostics allow the simultaneous analysis of the beam quality with the plasma parameters of the source. Regional funding request will also be needed to improve the LEBT for space charge compensation measurements. The design of the present and upgraded test bench will be reported as well as the first extracted beam analysis.

16.
Rev Sci Instrum ; 79(2 Pt 2): 02B723, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18315214

RESUMO

Based on the experience of the SILHI electron cyclotron resonance (ECR) ion source for the IPHI accelerator, which produces routinely 100-120 mA H(+) beam, the CEA-Saclay is in charge of the design and realization of the 140 mA cw deuteron source for the IFMIF project (International Fusion Materials Irradiation Facility). IFMIF is an accelerator-based neutron irradiation facility consisting of two accelerators of 125 mA D(+) beam at 40 MeV that hit in parallel a lithium target. IFMIF utilizes the deuteron-lithium (d-Li) neutron, producing a reaction to simulate the 14 MeV neutron environment in deuterium-tritium (D-T) fusion reactors. In the framework of the IFMIF EVEDA phase (Engineering Validation and Engineering Design Activities), we are studying a cw ECR ion source with a new extraction system to allow high current extraction while keeping a low divergence as well as a small emittance. Starting from SILHI five-electrode system with H(+) ions, the extracted beam characteristics as well as electric field conditions are compared with the cases of four- and three-electrode extraction systems. Experimental results made on the SILHI source with H(+) ions are briefly discussed. Extensive experimental results on the new source test bench BETSI are expected as soon as the design and fabrication of a dedicated extraction system with a new set of electrodes will be finished.

17.
Am J Physiol Renal Physiol ; 294(6): F1408-14, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18367658

RESUMO

Aging kidney is associated in humans and rodents with polyuria and reduced urine concentrating ability. In senescent female WAG/Rij rats, this defect is independent of arginine-vasopressin (AVP)/V(2) receptor/cAMP pathway. It has been attributed to underexpression and mistargeting of aquaporin-2 (AQP2) water channel in the inner medullary collecting duct (IMCD). We showed previously that dDAVP administration could partially correct this defect. Since AQP2 can also be regulated by AVP-independent pathways in water deprivation (WD), we investigated AQP2 and phosphorylated AQP2 (p-AQP2) regulation in thirsted adult (10 mo old) and senescent (30 mo old) female WAG/Rij rats. Following 2-day WD, urine flow rate decreased and urine osmolality increased in both groups. However, in agreement with significantly lower cortico-papillary osmotic gradient with aging, urine osmolality remained lower in senescent animals. WD induced sixfold increase of plasma AVP in all animals which, interestingly, did not result in higher papillary cAMP level. Following WD, AQP2 and p-AQP2 expression increased hugely in 10- and 30-mo-old rats and their mistargeting in old animals was corrected. Moreover, the age-related difference in AQP2 regulation was abolished after WD. To further investigate the mechanism of AQP2 underexpression with aging, AQP2 mRNA was quantified by real-time RT-PCR. In the outer medulla, preservation of AQP2 protein expression was achieved through increased AQP2 mRNA level in senescent rats. In the IMCD, no change in AQP2 mRNA was detected with aging but AQP2 protein expression was markedly lower in 30-mo-old animals. In conclusion, there is a posttranscriptional downregulation of AQP2 with aging, which is abolished by WD.


Assuntos
Envelhecimento/fisiologia , Aquaporina 2/genética , Aquaporina 2/metabolismo , Medula Renal/fisiologia , Privação de Água/fisiologia , Animais , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Regulação para Baixo/fisiologia , Feminino , Capacidade de Concentração Renal/fisiologia , Concentração Osmolar , Fosforilação , Processamento Pós-Transcricional do RNA/fisiologia , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Equilíbrio Hidroeletrolítico/fisiologia
18.
J Invest Dermatol ; 118(4): 678-85, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11918716

RESUMO

The purpose of this study was to examine the presence of aquaporin water channels in human skin and to assess their functional role. On western blots of human epidermis obtained from plastic surgery, a strong signal was obtained with polyclonal anti-aquaporin-3 antibodies. By indirect immunofluorescence on 5 microm cryosections, anti-aquaporin-3 antibodies strongly stained keratinocyte plasma membranes in human epidermis, whereas no staining was observed in the dermis or the stratum corneum or when anti-aquaporin-3 antibodies were preabsorbed with the peptide used for immunization. Similarly, a strong signal with anti-aquaporin-3 antibodies was observed in keratinocyte plasma membranes of reconstructed human epidermis in culture at the air-liquid interface for up to 3 wk. The keratinocyte plasma membrane localization of aquaporin-3 was confirmed at the electron microscope level in prickle cells. In addition an intracellular localization of aquaporin-3 was also detected in epidermis basal cells. Osmotically induced transepidermal water permeability was measured on stripped human skin and on reconstructed epidermis. Water transport across both stripped human skin and 2-3 wk reconstructed epidermis was comparable, inhibited by > 50% by 1 mM HgCl2 and fully inhibited by acid pH. By stopped-flow light scattering, keratinocyte plasma membranes, where aquaporin-3 is localized, exhibited a high, pH-sensitive, water permeability. Although human skin is highly impermeable to water, this is primarily accounted for by the stratum corneum, where a steep water content gradient was demonstrated. In contrast, the water content of viable strata of the epidermis is remarkably constant. Our results suggest that the human epidermis, below the stratum corneum, exhibits a high, aquaporin-3-mediated, water permeability. We propose that the role of aquaporin-3 is to water-clamp viable layers of the epidermis in order to improve the hydration of the epidermis below the stratum corneum.


Assuntos
Aquaporinas/metabolismo , Epiderme/metabolismo , Anticorpos , Aquaporina 3 , Aquaporinas/análise , Aquaporinas/imunologia , Western Blotting , Células Epidérmicas , Epiderme/química , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Queratinócitos/química , Queratinócitos/metabolismo , Queratinócitos/ultraestrutura , Microscopia Eletrônica , Osmose/fisiologia , Água/metabolismo
19.
J Craniofac Surg ; 12(6): 547-54, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11711821

RESUMO

SkullWiz is a computer-aided design program that transforms computer tomographic data of the neurocranium into a mathematical model that can be interactively manipulated to plan craniosynostosis surgery. Proper planning of this type of surgery involves reference to the underlying viscerocranium and to normal neurocranial dimensions, simulation of all basic surgical actions (closed and open osteotomy, translation, rotation, bending, removal, burring), and reference to the mechanical properties of calvarial bone at a given age. With SkullWiz, infinite trials are possible to develop a surgical plan that combines minimal action with maximum morphologic result. In contrast, physical models, e.g., foam milled or stereolitographic, provide just a single (or double, after gluing) opportunity to visualize three-dimensional morphology and simulate a treatment plan, without reference support. Validation of SkullWiz is difficult due to parameter variability. Its assets are therefore graphically exemplified in two common types of nonsyndromatic single-suture craniosynostosis-trigonocephaly and anterior plagiocephaly. SkullWiz is one of the most accurate planning tools currently available for craniosynostosis surgery. Accurate transfer of the planning by aluminium templates results in efficient and precise surgery by avoiding per-operative "chipping and fitting."


Assuntos
Desenho Assistido por Computador , Craniossinostoses/cirurgia , Planejamento de Assistência ao Paciente , Fatores Etários , Fenômenos Biomecânicos , Placas Ósseas , Parafusos Ósseos , Simulação por Computador , Nervos Cranianos/cirurgia , Suturas Cranianas/anormalidades , Suturas Cranianas/cirurgia , Craniotomia/métodos , Elasticidade , Feminino , Osso Frontal/anormalidades , Osso Frontal/cirurgia , Cabeça/cirurgia , Humanos , Lactente , Masculino , Modelos Anatômicos , Osteotomia/métodos , Osso Parietal/anormalidades , Osso Parietal/cirurgia , Rotação , Crânio/cirurgia , Software , Validação de Programas de Computador , Tomografia Computadorizada por Raios X
20.
Am J Physiol Renal Physiol ; 281(6): F1123-31, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11704564

RESUMO

The mechanisms underlying the prevention of age-related polyuria by chronic food restriction were investigated in female WAG/Rij rats. The decreased osmolality of renal papilla observed in senescent rats was not corrected by food restriction. A reduced urea content in the inner medulla of senescent rats, fed ad libitum or food-restricted, was suggested by the marked decrease in expression of UT-A1 and UT-B1 urea transporters. Aquaporin-2 (AQP2) downregulation in the inner medulla of senescent rats was partially prevented by food restriction. Both AQP2 and the phosphorylated form of AQP2 (p-AQP2), the presence of which was diffuse within the cytoplasm of collecting duct principal cells in normally fed senescent rats, were preferentially targeted at the apical region of the cells in food-restricted senescent animals. Plasma vasopressin (AVP) was similar in 10- and 30-mo-old rats fed ad libitum, but was doubled in food-restricted 30-mo-old rats. This study indicates that 1) kidney aging is associated with a marked decrease in AQP2, UT-A1, and UT-B1 expression in the inner medulla and a reduced papillary osmolality; and 2) the prevention of age-related polyuria by chronic food restriction occurs through an improved recruitment of AQP2 and p-AQP2 to the apical membrane in inner medulla principal cells, permitted by increased plasma AVP concentration.


Assuntos
Envelhecimento , Aquaporinas/metabolismo , Ingestão de Alimentos , Rim/metabolismo , Proteínas de Membrana Transportadoras , Poliúria/prevenção & controle , Vasopressinas/fisiologia , Animais , Aquaporina 2 , Aquaporina 6 , Proteínas de Transporte/metabolismo , Polaridade Celular , Feminino , Medula Renal/química , Medula Renal/metabolismo , Medula Renal/ultraestrutura , Túbulos Renais/metabolismo , Túbulos Renais/ultraestrutura , Glicoproteínas de Membrana/metabolismo , Concentração Osmolar , Fosforilação , Poliúria/etiologia , Poliúria/metabolismo , Transporte Proteico , Ratos , Urina/química , Vasopressinas/sangue , Desequilíbrio Hidroeletrolítico/etiologia , Desequilíbrio Hidroeletrolítico/metabolismo , Transportadores de Ureia
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