Specific Reaction Path Hamiltonian for Proton Transfer in Water: Reparameterized Semiempirical Models

The semiempirical MNDO-based AM1 and PM3 methods and the orthogonalization-corrected OM1, OM2, and OM3 models were reparameterized to improve their description of bulk water and of proton transfer in water. Reference data included the gas-phase geometries and energies of the water molecule, small water clusters, the hydronium ion, and small hydronium ion–water clusters, as well as the gas-phase potential energy surface for proton transfer between the two water molecules in a Zundel ion, all calculated at the MP2/aug-cc-pVTZ level of theory. Combined QM/MM molecular dynamics simulations were carried out for bulk water and for a proton solvated in water using large cluster models. Both the authentic and reparameterized semiempirical models were employed in the simulations. The reparameterization led to significantly better results in all cases. The new set of OM3 parameters gave the best overall results for the structural and dynamic properties of water and the hydrated proton, with a small but finite barrier of 0.1–0.2 kcal/mol in the potential of mean force for proton transfer, in agreement with ab initio path-integral molecular dynamics simulations. The reparameterized OM3 model is expected to be useful for efficient modeling of proton transfer in aqueous solution

Hawaii energy strategy project 2: Fossil energy review. Task 3 -- Greenfield options: Prospects for LNG use

This paper begins with an overview of the Asia-Pacific LNG market, its major players, and the likely availability of LNG supplies in the region. The discussion then examines the possibilities for the economic supply of LNG to Hawaii, the potential Hawaiian market, and the viability of an LNG project on Oahu. This survey is far from a complete technical assessment or an actual engineering/feasibility study. The economics alone cannot justify LNG`s introduction. The debate may continue as to whether fuel diversification and environmental reasons can outweigh the higher costs. Several points are made. LNG is not a spot commodity. Switching to LNG in Hawaii would require a massive, long-term commitment and substantial investments. LNG supplies are growing very tight in the Asia-Pacific region. Some of the environmental benefits of LNG are not entirely relevant in Hawaii because Hawaii`s air quality is generally excellent. Any air quality benefits may be more than counterbalanced by the environmental hazards connected with large-scale coastal zone construction, and by the safety hazards of LNG carriers, pipelines, etc. Lastly, LNG is not suitable for all energy uses, and is likely to be entirely unsuitable for neighbor island energy needs

Enhanced chondrogenic differentiation of bone marrow mesenchymal stem cells on gelatin/glycosaminoglycan electrospun nanofibers with different amount of glycosaminoglycan

Tissue engineering is a new technique to help damaged cartilage treatment using cells and scaffolds. In this study we tried to evaluate electrospun scaffolds composed of gelatin/glycosaminoglycan (G/GAG) blend nanofibers in chondrogenesis of bone marrow-derived mesenchymal stem cells (BMMSCs). Scaffolds were fabricated by electrospinning technique with different concentration of glycosaminoglycan (0, 5, 10, and 15) in gelatin matrix. BMMSCs were cultured on the scaffolds for chondrogenesis process. MTT assay was done for scaffold's biocompatibility and cells viability evaluation. Alcian blue staining was carried out to determine the release of GAG and reverse transcription polymerase chain reaction (RT-PCR) was done for expression of COL2A1 and also immunocytochemistry assay were used to confirm expression of type II collagen. Scaffold with 15 GAG showed better result for biocompatibility (p =0.02). Scanning electron microscopy (SEM) micrographs showed that MSCs have good attachment to the scaffolds. Alcian blue staining result confirmed that cells produce GAG during differentiation time different from GAG in the scaffolds. Also the results for RT-PCR showed the expression of COL2A1 marker. Immunocytochemistry assay for type II collagen confirm that this protein expressed. Scaffold comprising 15 GAG is better results for chondrogenesis and it can be a good applicant for cartilage tissue engineering. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 38�48, 2019. © 2018 Wiley Periodicals, Inc

Posttransplant malignancies and their relationship with human leukocyte antigens in kidney allograft recipients.

INTRODUCTION: Kidney transplant recipients are at increased risk of cancers, most frequently skin cancers, and in some regions, Kaposi sarcoma and non-Hodgkin lymphoma. We sought to investigate the associate of the most frequent malignancies among our patients with human leukocyte antigens (HLAs). MATERIALS AND METHODS: We performed a retrospective study on 44 kidney allograft recipients who had posttransplant malignancy and 44 kidney allograft recipients without malignant lesions (control group). All of the patients had been treated by immunosuppressive regimens including cyclosporine plus prednisolone or cyclosporine, prednisolone, and mycophenolate mofetil. Data on HLA typing were achieved from their transplant records. RESULTS: There were 15 patients (34.1) with Kaposi sarcoma; 13 (29.6) with non-Hodgkin lymphoma, 6 (13.6) with skin cancer, 2 (4.5) with ovary cyst adenocarcinoma, and 8 (18.2) with other tumors. The mean interval from transplantation to diagnosis of malignancy was 15.3 month. Twelve patients died of cancer during the follow-up (mean, 12.3 years). No significant difference was noted in the age, sex, and time of transplantation between these patients and those in the control group. Kaposi sarcoma was associated with HLA-CW4 (P = .03) with an odds ratio of 4.96 (95 confidence interval, 2.90 to 8.12). CONCLUSIONS: We found HLA-CW4 as a risk factor of Kaposi sarcoma in kidney allograft recipients. Screening for malignancies after kidney transplantation sounds very important with special attention to the specific environmental and genetic factors in each population

Posttransplant malignancies and their relationship with human leukocyte antigens in kidney allograft recipients.

INTRODUCTION: Kidney transplant recipients are at increased risk of cancers, most frequently skin cancers, and in some regions, Kaposi sarcoma and non-Hodgkin lymphoma. We sought to investigate the associate of the most frequent malignancies among our patients with human leukocyte antigens (HLAs). MATERIALS AND METHODS: We performed a retrospective study on 44 kidney allograft recipients who had posttransplant malignancy and 44 kidney allograft recipients without malignant lesions (control group). All of the patients had been treated by immunosuppressive regimens including cyclosporine plus prednisolone or cyclosporine, prednisolone, and mycophenolate mofetil. Data on HLA typing were achieved from their transplant records. RESULTS: There were 15 patients (34.1) with Kaposi sarcoma; 13 (29.6) with non-Hodgkin lymphoma, 6 (13.6) with skin cancer, 2 (4.5) with ovary cyst adenocarcinoma, and 8 (18.2) with other tumors. The mean interval from transplantation to diagnosis of malignancy was 15.3 month. Twelve patients died of cancer during the follow-up (mean, 12.3 years). No significant difference was noted in the age, sex, and time of transplantation between these patients and those in the control group. Kaposi sarcoma was associated with HLA-CW4 (P = .03) with an odds ratio of 4.96 (95 confidence interval, 2.90 to 8.12). CONCLUSIONS: We found HLA-CW4 as a risk factor of Kaposi sarcoma in kidney allograft recipients. Screening for malignancies after kidney transplantation sounds very important with special attention to the specific environmental and genetic factors in each population

Risk factors for delayed graft function in deceased donor kidney transplantation; A potential preventive role for intraoperative thymoglobulin

Introduction: Delayed graft function (DGF) is associated with significant adverse outcomes in deceased donor kidney transplantation (KT) including lower graft survival. However, risk factors and potential preventive strategies like intraoperative rabbit antithymocyte globulin (rATG; thymoglobulin) have not yet been fully evaluated. Objectives: The aim of this study was to investigate DGF risk factors and determine the association of intraoperative rATG with the risk of DGF in deceased donor kidney recipients. Patients and Methods: We retrospectively examined medical records of 163 first time deceased donor kidney transplant recipients at two major kidney transplant centers from 2014 to 2016. All the donors were standard heart-beating, brain death donors. Risk factors for DGF in recipients were evaluated using multivariate logistic regression analysis. Results: The mean recipients' age was 43±13 years and the majority of participants were male (64). The overall rate of DGF was 27. Intraoperative rATG was significantly associated with a lower rate of DGF (adjusted odds ratio AOR, 0.33, 95% CI, 0.11-0.95). Intraoperative transfusion (AOR, 3.7, 95% CI, 1.4-9.9) and diabetes mellitus (AOR, 3.7, 95% CI, 1.5-8.9) were significantly associated with higher risk of DGF. Conclusion: This study showed that intraoperative blood transfusion and diabetes mellitus were associated with increased risk of DGF. Meanwhile, administration of intraoperative rATG was associated with reduced odds ratio of DGF. Future studies are needed to evaluate the potential role of rATG in DGF-related renal outcomes. © 2019 The Author(s)