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101.
Rodríguez-Mulero S Errasti-Murugarren E Ballarín J Felipe A Doucet A Casado FJ Pastor-Anglada M 《Kidney international》2005,68(2):665-672
BACKGROUND: The renal reabsorption of natural nucleosides and a variety of nucleoside-derived drugs relies on the function of the apically located, Na(+)-dependent, concentrative nucleoside transporters CNT1, CNT2, and CNT3 (SLC28A1, SLC28A2, and SLC28A3). The aims of this study were to determine the segmental localization of the three SLC28 family members and to establish whether streptozotocin-induced diabetes alters their expression. METHODS: SLC28 expression was measured by real-time polymerase chain reaction (PCR) on microdissected sections of rat nephrons. Diabetes was induced by streptozotocin treatment and the biochemical profiles of control, diabetic, and insulin-treated rats were established. The effect of diabetes on SLC28 expression was assessed in those segments that significantly express SLC28 genes. RESULTS: CNT1-3 mRNAs were expressed in the proximal tubule and glomerulus. In addition, CNT2 and CNT3 mRNAs were expressed in the outer medullary and cortical collecting duct, respectively. Diabetes reduced expression of the three CNTs in almost all nephron segments, and this effect was not prevented by an insulin treatment that normalized all blood and urine parameters. Diabetes increased CNT1 and CNT3 expression in the glomerulus and insulin treatment decreased it. CONCLUSION: The relative distribution of SLC28 gene expression suggests a role for the proximal tubule in renal nucleoside clearance and an accessory role for CNT2 and CNT3, in adenosine-mediated regulation of collecting duct functions. Diabetes probably may impair nucleoside clearance independently of insulin. 相似文献
102.
Calligaro KD Toursarkissian B Clagett GP Towne J Hodgson K Moneta G Sidawy AN Cronenwett JL;Clinical Practice Council Society for Vascular Surgery 《Journal of vascular surgery》2008,47(1):1-5
The Clinical Practice Council of the Society for Vascular Surgery (SVS) was charged with providing an updated consensus on guidelines for hospital privileges in vascular and endovascular surgery. One compelling reason to update these recommendations is that vascular surgery as a specialty has continued to evolve with a significant shift towards endovascular therapies. The Society for Vascular Surgery is making the following four recommendations concerning guidelines for hospital privileges for vascular and endovascular surgery. First, anyone applying for new hospital privileges to perform vascular surgery should have completed an Accreditation Council for Graduate Medical-accredited vascular surgery residency and should obtain American Board of Surgery certification in vascular surgery within 3 years of completion of their training. Second, we reaffirm and provide updated recommendations concerning previous established guidelines for peripheral endovascular procedures, thoracic and abdominal aortic endograft replacements, and carotid artery balloon angioplasty and stenting for trainees and already credentialed physicians who are adding these new procedures to their hospital credentials. Third, we endorse the Residency Review Committee for Surgery recommendations regarding open and endovascular cases during vascular residency training. Fourth, we endorse the Inter-societal Commission for Accreditation of Vascular Laboratories (ICAVL) recommendations for noninvasive vascular laboratory interpretations and examinations to become a registered physician in vascular interpretation (RPVI) or a registered vascular technologist (RVT). 相似文献
103.
Karla Sofía Snchez-Zambrano Marina Hernndez-Resndiz Cristian Gmez-Rodríguez Linda Viviana García-Quionez Josu Amilcar Aguilar-Martínez Edn Amaral Rodríguez-Castellanos Luis Felipe Verdeja Daniel Fernndez-Gonzlez Guadalupe Alan Castillo-Rodríguez 《Materials》2022,15(9)
In this work, we studied the phases in a Mg-Ti-O system using a 1:1 formulation of MgO:TiO2, mixing synthetic brucite of Mexican origin with TiO2 microparticles of high purity, with a heat treatment at 1100 °C for 1 h. Due to its valence electrons, TiO2 can contribute to the sintering process to improve density in MgO products. The raw materials and formulation by XPS and X-RD techniques were characterized. The results demonstrate the presence of different oxidation states in titania and the formation of different oxides in the Mg-Ti-O system when mixed and calcined at 1100 °C; additionally, we estimated the formation of vacancies in the crystal lattice during the transformation from hexagonal brucite to magnesia with a cubic structure centered on the faces. Its thermal behavior is indicated by the MgO-TiO2 phase diagram. 相似文献
104.
105.
G.N. Stradling S.A. Gray J.C. Moody A. Hodgson K.N. Raymond P.W. Durbin 《International journal of radiation biology》2013,89(5):1269-1277
SummaryA hydroxypridinone derivative of desferrioxamine (Na-DFO-HOPO), a dihydroxamic derivative of diethylenetriaminepenta-acetic acid (ZnNa-DTPA-DX), and DTPA (CaNa3- and ZnNa3-DTPA) were tested at dosages of 30 μmol kg?1 for their ability to remove 238Pu or 241Am from rats after their intravenous injection as citrate or inhalation as nitrate. The most effective treatment regimen for injected Pu was the repeated administration of DFO-HOPO; by 7 days the body content was reduced to 8% of that in untreated animals. Repeated dosages of 3 μmol kg?1 DFO-HOPO were as effective as those of 30 μmol kg?1 DTPA. After inhalation of Pu nitrate, repeated treatment with DTPA, DTPA-DX or DFO-HOPO reduced the body content by 7 days to, respectively, 10, 15 and 31% of those in untreated animals. After inhalation of Am, DTPA-DX and DTPA were equally effective, the body contents being reduced to 7% of control values with repeated treatment. Injection of DFO-HOPO was ineffective for enhancing the elimination of inhaled or injected Am. The results confirm the strategy of examining the use of siderophore analogues for the decorporation of Pu or Am. However, at present DTPA should remain the agent of choice, particularly after inhalation. 相似文献
106.
107.
Maureen P. Davey Karni Kissil Laura Lynch La-Rhonda Harmon Nancy Hodgson 《Journal of cancer education》2012,27(4):744-751
Prior clinical research supports the effectiveness of cancer support groups for cancer patients and their families, yet African-American families continue to be underrepresented in cancer support groups and in cancer clinical research studies. In order to fill this gap, we developed and evaluated a culturally adapted family support group for African-American families coping with parental cancer. We encountered unexpected challenges in overcoming barriers to recruitment, partnering with oncology providers, and building trust with the African-American community and African-American families coping with parental cancer. We describe actions taken during the two phases of this study and lessons learned along the way about recruiting and engaging African-American families in cancer support group studies, partnering with oncology providers, networking with the African-American community, and the importance of demonstrating cultural sensitivity to overcome the understandable historical legacy of mistrust. 相似文献
108.
109.
110.
Luiz Alberto Forgiarini Gustavo Grün Nélson Alexandre Kretzmann Gustavo Alfredo Ochs de Muñoz Antonino de Almeida Luiz Felipe Forgiarini Cristiano Feijó Andrade 《The Journal of surgical research》2013,179(1):168-174
ObjectiveTo verify the impact of ischemic time on lung cell viability in an experimental model of lung ischemia–reperfusion (IR) injury and its repercussion on lung performance after reperfusion.MethodsTwenty-four animals were subjected to selective clamping of the left pulmonary artery and divided into four groups (n = 6) according to ischemic time: 15 (IR15), 30 (IR30), 45 (IR45), and 60 min (IR60). All animals were observed for 120 min after reperfusion. The hemodynamics, arterial blood gases measurements, and histologic changes were analyzed. Immunofluorescence assays for caspase 3 and annexin V were performed. Lipid peroxidation was assessed by thiobarbituric acid–reactive substances, and caspase 3 activity was assessed by colorimetric extract.ResultsThe partial pressure of arterial oxygen significantly decreased at the end of the observation period in the IR30, IR45, and IR60 groups (P < 0.05). The final mean arterial pressure significantly decreased in the IR60 group (P < 0.05). We observed a significant increase in caspase 3 activity and caspase 3–positive cells by immunofluorescence in the IR45 group compared with the other groups (P < 0.05). Additionally, there was an increase in necrotic cells assessed by annexin V in the IR60 group. The histologic score did not show differences among the different groups.ConclusionsThe degree of cell damage had a negative impact on lung performance. Sixty minutes of lung ischemia and posterior reperfusion resulted in an increased number of necrotic cells, suggesting that these cells may not be able to reverse the effects of the IR injury because of the lack of viable cells. 相似文献