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71.
Insulin induces vasodilatation in human subjects and increases l-arginine transport and NO synthesis in human umbilical vein endothelial cells (HUVEC). Cell signalling events associated with insulin effects on activity and mRNA expression of the human cationic amino acid transporters 1 (hCAT-1) and 2B (hCAT-2B) are unknown. l-Arginine transport and eNOS activity were determined in HUVEC exposed to insulin. mRNA levels for hCAT-1, hCAT-2B and eNOS were quantitated by real time RT-PCR and endothelial NO synthase (eNOS) protein was identified by Western blot analysis. Intracellular Ca2+, l-arginine and l-citrulline levels, l-[3H]citrulline formation from l-[3H]arginine, cGMP formation, nitrite level, ATP release and membrane potential were determined. Insulin increased l-arginine transport and the mRNA levels for hCAT-1 and hCAT-2B and eNOS expression and activity. Insulin also induced membrane hyperpolarization and increased intracellular Ca2+, l-[3H]citrulline, cGMP and nitrite formation. Insulin-mediated stimulation of the l-arginine/NO pathway is thus associated with increased hCAT-1 and hCAT-2B mRNA, and eNOS expression, via mechanisms involving membrane hyperpolarization, mitogen-activated protein kinases p42 and p44, phosphatidylinositol 3-kinase, NO and protein kinase C. We have characterized a cell signalling pathway by which hyperinsulinaemia could lead to vasodilatation in human subjects, and which could have implications in patients in whom plasma insulin levels are altered, such as in diabetes mellitus.  相似文献   
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The binary polymeric systems formed by some poly(mono-n-alkyl itaconates) and poly(2-vinylpyridine) or poly(4-vinylpyridine) are studied. Depending on the solvent, two different types of material have been synthesized. On the one hand, using methanol as common solvent, we have obtained solid polymer-polymer complexes the composition of which is determined by the initial mixing conditions. On the other hand, pyridine avoids the complexation process, allowing to obtain a true solution of both polymers and, therefore, a solid polymer blend of known composition by solvent casting. Yields of the complexation and stoichiometries of the polymer-polymer complexes have been analysed. In this way, a favoured composition in the range from 3:2 to 1:1 for the mole ratio (referring to repeating units) ratio poly(mono-n-alkyl itaconate):poly(vinylpyridine) was observed depending on the poly-(mono-n-alkyl itaconate used). Differential Scanning Calorimetry and thermogravimetry have been employed to study the thermal behaviour of complexes and blends. Viscometry measurements have been performed to analyse the interactions in solution. One of the aims of this work has been to analyse the effect of the side group of the poly-(mono-n-alkyl itaconate) in the mixing process as well as in the characteristics of the final products. In this way, higher complexation yields have been obtained using poly-(mono-n-alkyl itoconates) with longer n-alkyl side groups due to the additional stabilisation by solvophobic interactions. On the other hand, the poly(mono-n-alkyl itaconates) with longer n-alkyl groups form polymer-polymer complexes with a higher proportion of poly(4-vinylpyridine), presumably due to their slower kinetics of complexation.  相似文献   
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PurposePediatric gastrostomy tubes (G-tubes) are associated with considerable utilization of healthcare resources. G-tube dislodgement can result in tract disruption and abdominal sepsis. We aimed to reduce early G-tube dislodgement by 25%.MethodsAn interdisciplinary team convened to identify key drivers of G-tube dislodgement and implement initiatives to reduce this complication. A G-tube care bundle was implemented in 2018. Rates of early G-tube dislodgement (within 90 days of insertion) were tracked. 15 months of cases after bundle implementation were compared to 20 months of cases before implementation. Length of stay (LOS, balancing measure) and bundle compliance (process measure) were tracked.ResultsG-tube dislodgements decreased 47% after bundle implementation. Overall, dislodgements after G-tube insertion decreased from 43% to 19% dislodgements per tube inserted, p = 0.004. Reductions were observed for dislodgements occurring in both the inpatient (14% vs. 1.5%) and outpatient (29% vs. 18%) settings. Median LOS was reduced from 15.3 to 7.1 days following implementation, p = 0.004. Process measures demonstrated 75% or greater compliance one year after implementation.ConclusionAn interdisciplinary team using quality improvement science methodology can significantly reduce G-tube dislodgement and improve value after pediatric gastrostomy tube insertion.Type of studyLongitudinal cohort study.Level of evidenceIII.  相似文献   
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ContextThymoglobulin is used effectively as induction agent in kidney transplantation but the optimal dose is not well established.ObjectiveDemonstrate that low-dose thymoglobulin (3 mg/kg) has similar efficacy and safety compared to basiliximab induction in low-risk kidney transplantation under standard maintenance immunosuppressionDesign, Setting, ParticipantsProspective randomized study in kidney transplant patients (12/2016-05/2018). Inclusion criteria: Recipients > 18 years, first living donor transplant. Exclusion criteria: Second and multiorgan transplant, ABO incompatibility, positive cross-match, panel reactive antibodies (PRA) > 30%, positive donor-specific antibody, human immunodeficiency virus, hepatitis B surface antigen, hepatitis C virus positive, white blood cells < 2000 cells/mm3, platelets < 75,000 cells/mm3 and malignancy.InterventionGroup A: basiliximab (20 mg D0 and D4). Group B: thymoglobulin (3 mg/kg total). Maintenance immunosuppression: tacrolimus, mycophenolate mofetil, and steroids.Main Outcome MeasuresBiopsy-proven acute rejection (BPAR), delayed graft function, slow graft function, leukopenia, infections, adverse events, graft loss, estimated glomerular filtration rate, and death within 12 months.Results100 patients (basiliximab, n = 53) (thymoglobulin, n = 47) were included. Donor and recipient characteristics were similar except for longer dialysis (basiliximab), PRA class I (1.2% basiliximab, 4.5% thymoglobulin), HLA match (basiliximab 2.8, thymoglobulin 2.2), and cytomegalovirus status. BPAR rate was basiliximab 3.8% and thymoglobulin 6.4% (P = ns). Delayed graft function (basiliximab 3.8%; thymoglobulin 4.3%), slow graft function, and 12-month leukopenia (basiliximab 11.3%, thymoglobulin 21.3%) were similar between groups (P = ns). There was no difference in infections and adverse events between groups. Patient and graft survival were as follows: basiliximab 98.1% and 92.5%, thymoglobulin 100% and 93.6% (P = ns).ConclusionLow-dose thymoglobulin induction (3 mg/kg) can be used effectively and safely in low-risk kidney transplantation with good results during the first year post-transplant.  相似文献   
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Transplantation of any organ has some inherent risk of disease transmission, such as infection and malignancy. The present study aims to describe 2 cases of choriocarcinoma transmission after kidney and liver transplantation originating from the same patient. The donor was a 17-year-old woman who died of cerebral hemorrhage. Both organ recipients died of metastatic choriocarcinoma few months after the transplantation, within days after starting chemotherapy. Retrospective hCG (human chorionic gonadotropin hormone) analysis in donor's blood stored at the time of donation had a result of 9324 mIU/mL. Despite its rarity, clinicians should be aware of the risk of transplant-related choriocarcinoma from female donors in childbearing age. In some cases, hCG dosage should be performed before donation.  相似文献   
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During the peri-coronavirus disease 2019 pandemic, the need of special care has raised, not only for our patients but also for health care workers. These needs are different regarding the procedure and the approach performed. This is a dynamic review in the use of robotics and transanal approaches for colorectal diseases. We searched PubMed and KSREvidence.com for studies related to coronavirus disease and robotic surgery/transanal mesorectal excision/transanal surgery(primary and systematic reviews). From 147 results in PubMed, 11 were selected for full text screening, and 11 were included in this paper. From 3 results in KSREvidence, no relevant systematic reviews were identified. We also checked the references in identified papers for further relevant studies. European Society of Coloproctology guidelines were including as part of the recommendations available. Robotic and transanal MIS can be performed safely during the pandemic, but particular characteristics of these procedure need to be taken into consideration.  相似文献   
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