Evaluation of Organic Hydride/Acid Pairs as a Type of Thermodynamic-Potential-Regulated Multisite Proton-Coupled Electron Transfer Reagents.

Organic hydride/acid pairs have been reported as multisite proton-coupled electron transfer (MS-PCET) reagents in reductive MS-PCET reactions recently. Since the key step for an organic hydride/acid pair acting as an MS-PCET reagent is a chemical process of the organic hydride/acid pair releasing a formal hydrogen atom, the bond dissociation free energy of the organic hydride/acid pair releasing a formal hydrogen atom is a valuable thermodynamic parameter for objectively evaluating the thermodynamic potential for an organic hydride/acid pair to act as an MS-PCET reagent. Now, organic hydride/acid pairs of 216 organic hydrides have been demonstrated to be a potential type of thermodynamically potential-regulated MS-PCET reagent. Without a doubt, organic hydride/acid pairs reflect the change of N-substituted organic hydrides from simple hydride reductants to thermodynamically-regulated MS-PCET reagents, which could significantly expand the availability of novel MS-PCET reagents.

Discovering and Evaluating the Reducing Abilities of Polar Alkanes and Related Family Members as Organic Reductants Using Thermodynamics.

In this work, the pKa values of 69 polar alkanes (YH2) in acetonitrile were computed using the method developed by Luo and Zhang in 2020, and representative 69 thermodynamic network cards on 22 elementary steps of YH2 and related polar alkenes (Y) releasing or accepting H2 were naturally established. Potential electron reductants (YH-), hydride reductants (YH-), antioxidants (YH2 and YH-), and hydrogen molecule reductants (YH2) are unexpectedly discovered according to thermodynamic network cards. It is also found that there are great differences between YH2 and common hydrogen molecule reductants (XH2), such as Hantzsch ester (HEH2), benzothiazoline (BTH2), and dihydro-phenanthridine (PH2), releasing two hydrogen ions to unsaturated compounds. During the hydrogenation process, XH2 release hydrides first, then the oxidation state XH+ release protons. However, in the case of YH2, YH2 release protons first, then YH- release hydrides. It is the differences on acidic properties of YH2 and XH2 that result in the behavioral and thermodynamic differences on YH2 and XH2 releasing two hydrogen ions (H--H+). The redox mechanisms and behaviors of Y, YH-, and YH2 as electron, hydrogen atom, hydride, and hydrogen molecule donors or acceptors in the chemical reaction are reasonably investigated and discussed in this paper using thermodynamics.

Influence of dietary protein on serum phosphorous levels in peritoneal dialysis patients with different initial transport function.

INTRODUCTION: This cross-sectional study investigated the influence of dietary protein intake (DPI) on serum phosphate levels in peritoneal dialysis (PD) patients and determined the DPI cutoff required to prevent hyperphosphatemia. METHODS: A total of 504 PD patients were categorized into fast (4 h dialysate/plasma [D/P] creatinine clearance ≥0.65) or slow (<0.65) peritoneal transporters. Serum phosphorus and peritoneal solute clearance were compared between the groups with different DPI. RESULTS: The fast peritoneal transporters (n = 233) were older, had lower serum albumin and phosphorus levels, and had higher peritoneal phosphorus clearance (all p < 0.001). Among the slow transporters (n = 271), serum phosphorus levels were significantly higher among patients with DPI > 1.0 g/kg/d (p < 0.001). High DPI only increased the hyperphosphatemia risk in slow transporters (not in high transporters). DPI ≥1.026 g increased the hyperphosphatemia risk in those patients (area under the curve: 0.66, p = 0.001). CONCLUSION: High DPI increases the hyperphosphatemia risk in PD patients with slower peritoneal transport function.

Characterizing the impact of Three Gorges Dam on the Changjiang (Yangtze River): A story of nitrogen biogeochemical cycling through the lens of nitrogen stable isotopes.

The alterations of nitrogen sources and cycling within the Three Gorges Reservoir (TGR) and downstream the Changjiang were investigated to understand the impacts of the construction of the Three Gorges Dam (TGD) and anthropogenic inputs from the associated watershed. Water samples collected in October 2016 were analyzed for hydrologic parameters, nutrient concentrations, and stable isotopes of nitrate (NO3-), ammonium (NH4+) and particulate matter. Nitrate dual stable isotope values ranged from +5.8‰ to +7.1‰ and -1.9‰ to +0.4‰ for δ15N and δ18O, respectively. δ15N values in particulate nitrogen (PN) ranged from +0.5‰ to +8.5‰, with slightly lower values before the dam. δ15N-NH4+ values ranged between +10.5‰ and +19.4‰, likely reflecting the presence of ammonium assimilation throughout the TGR. The contribution of different nitrogen sources was calculated using a Bayesian mixing model. These sources, including soil organic nitrogen, ammonium fertilizer, and sewage effluent, contributed to elevated DIN concentrations within the TGR (83.2 µM-178.5 µM). The construction of the dam has also likely induced changes in the river environment such as ammonium assimilation in the surface waters and nitrification and/or remineralization within the deep waters of the TGR. Overall, during this investigation period, the TGR acted as a sink of PN (retaining 29%), yet negligibly influenced levels of TDN with ~96.5% of TDN exported to the downstream Changjiang and estuary. It is important to understand the long-term impacts of the TGD on the ecological environment of the Changjiang. This study highlights the influence that anthropogenic nitrogen sources have on the natural biogeochemical cycling within the TGR, showing the urgent need to reduce anthropogenic nitrogen pollution.

New Insights into Sediment Transport in Interconnected River-Lake Systems Through Tracing Microorganisms.

A growing awareness of the wider environmental significance of diffuse sediment pollution in interconnected river-lake systems has generated the need for reliable provenance information. Owing to their insufficient ability to distinguish between multiple sources, common sediment source apportionment methods would rarely be a practical solution. On the basis of the inseparable relationships between sediment and adsorbed microorganisms, community-based microbial source tracking may be a novel method of identifying dominant sediment sources in the era of high-throughput sequencing. Dongting Lake was selected as a study area as it receives considerable sediment import from its inflowing rivers during the flood season. This study was conducted to characterize the bacterial community composition of sediment samples from the inflow-river estuaries and quantify their sediment microbe contributions to the central lake. Metagenomic analysis revealed that the community compositions of source sediment samples were significantly different, allowing specific sources to be identified with the machine learning classification program SourceTracker. A modified analysis using SourceTracker found that the major contributors to three major lake districts were the Songzi, Zishui, and Xinqiang Rivers. The impacts of hydrodynamic conditions on source apportionment were further verified and suggested the practicability of this method to offer a systematic and comprehensive understanding of sediment sources, pathways, and transport dynamics. Finally, a novel framework for sediment source-tracking was established to develop effective sediment management and control strategies in river-lake systems.

An environmental flow assessment of a river's blocking effect on a lake in a river-lake system: application in the Yangtze-Poyang system.

Hydrologic regimes are essential to riverine, lacustrine, and wetland ecosystems, and every component of a hydrologic regime has a specific ecological environmental function. In an outflow lake-river system, water levels are reduced by a reservoir constructed at the river, which interferes with the river-lake interrelationships by impairing the river's blocking effect. This increases the lake-river hydraulic gradient and accelerates the lake's drainage to the river, resulting in shrinkage of the lake and damaging environmental issues. To respond to these issues, we propose an environmental flow assessment that considers the river's blocking effect on the lake. This novel methodology consists of four steps: data preparation, assessment of the lake's environmental water level, assessment of the river's environmental water level, and environmental flow assessment. We estimated the river's environmental water level through a hydraulic correlation between the lake and the river, and found that the river's blocking effect could be sustained. The Yangtze-Poyang system was selected as a case study to illustrate the methodology's procedures and applicability. The impoundment of the Three Gorges Reservoir, during the fall retreating season, decreased the Yangtze's water level and weakened the Yangtze's blocking effect on Poyang Lake. Poyang Lake's environmental water level, which ranges from 11.71 to 15.81 m in the month of October, was used to estimate the Yangtze's environmental water level as falling in a range of 11.95 to 16.17 m, which corresponds to an environmental flow range of 16,822 to 32,371 m3/s. This study offers a solution for reservoir-induced accelerated lake drainage, which may be helpful in mitigating the negative impacts of reservoirs and sustaining natural rive-lake interactions.

Development and validation of a bacteria-based index of biotic integrity for assessing the ecological status of urban rivers: A case study of Qinhuai River basin in Nanjing, China.

With the increasing human disturbance to urban rivers, the extinction and biodiversity losses of some macroorganism species decreased the accuracy of bioassessment. In this study, a novel index of biotic integrity based on bacteria (Ba-IBI) was first developed for Qinhuai River in Nanjing city, China. Thirty-two biofilm samples were collected along the river bank and the bacterial communities were identified by high-throughput sequencing. By the range, responsive, and redundancy tests, four core metrics were selected from the dataset of 78 candidate metrics, including Pielou's evenness index, proportion of Paenibacillus, proportion of OTUs tolerant to organic pollution and proportion of Nitrosomonas. The results showed that the Ba-IBI was able to effectively discriminate different impaired site groups, and had a good correlation with the index of water quality (r = 0.79, p < 0.01) and the qualitative habitat evaluation index (r = 0.51, p < 0.01). Moreover, the Ba-IBI was negatively correlated with the number of population within a 1 km buffer (r = -0.71, p < 0.01). Application of the index showed that most of the sites were in the poor or bad class in the river. Our study revealed that the Ba-IBI is an effective and reliable approach for assessing the ecological status of Qinhuai River basin, which can complement the existing ecological assessment approaches for urban rivers. Meanwhile, repeted surveys and field validations are still needed to further improve the applicability of the index in future studies.

Epimerization of C5 of an N-hydroxypyrrolidine in the synthesis of swainsonine related iminosugars.

Epimerization of C5 of an N-hydroxypyrrolidine ring by regioselective oxidation to a nitrone followed by diastereoselective reduction provides a new approach to the synthesis of swainsonine and related compounds. The only protection in the synthesis of the potent mannosidase inhibitor DIM (1,4-dideoxy-1,4-imino-d-mannitol) was the acetonation of d-mannose.

Impacts of reservoirs on the streamflow and sediment load of the Hanjiang River, China.

The Hanjiang River is an important tributary of the Yangtze River in China. Long-term observed streamflow and sediment load data that spanned 1951-2014 was collected from the Huangzhuang hydrometric station, which is located at the middle reaches. The data was analyzed to reveal the impacts of reservoirs on streamflow and sediment load of the Hanjiang River. The coefficient of variation (C v) and concentration degree (C d) were applied to describe the intra-annual distribution characteristics. Abrupt changes in the time series of the streamflow and sediment load were detected by the heuristic segmentation algorithm. The annual streamflow significantly decreased from 1561 to 1263 m3/s after 1991, which was mainly caused by climate change. Two significant change points in the annual sediment load series occurred at 1966 and 1985, and the average values of the sub-series were 3198, 952, and 251 kg/s, respectively. Significant change points in the C v and C d series of the streamflow and sediment load occurred around 1967. The C v and C d series decreased dramatically after the change points. Abrupt changes in the time series of the streamflow and sediment load mainly occurred around 1967 when the Danjiangkou reservoir began to impound water, indicating that the Danjiangkou reservoir was an important factor that caused hydrological changes. The reservoir trapped sediment, reduced sediment concentration, mitigated the monthly streamflow and sediment load fluctuations, and reduced the intra-annual variation and concentration. Assessed by the range of variability approaches, the overall alteration degrees of the streamflow and sediment regimes were 36 and 60 %, respectively, which qualified as a moderate degree. The reservoir exerted greater influence on the sediment regime than on the streamflow regime.

Increased miR-155 expression in peripheral blood mononuclear cells of primary immune thrombocytopenia patients was correlated with serum cytokine profiles.

We investigated the possible pathogenic role of a microRNA (miR-155) in primary immune thrombocytopenia (ITP). We used quantitative real-time PCR to determine the relative expression of miR-155 and SOCS1 (suppressor of cytokine signaling) mRNA in peripheral blood mononuclear cells (PBMCs) from 28 ITP patients and 28 healthy controls. Cytokine plasma levels were determined by ELISA. Possible associations between miR-155 levels and serum cytokine concentrations were assessed using Spearman or Pearson correlation analysis. Seven naive ITP patients were followed and the effects of medical treatment on miR-155 levels were assessed. Compared to healthy controls, ITP patients had increased miR-155 and decreased SOCS1 mRNA levels. ITP patients also had increased plasma IL-17A and decreased IL-4, IL-10 and TGF-ß1 levels. miR-155 levels were negatively correlated with platelet counts, SOCS1 mRNA levels, and the plasma levels of IL-4, IL-10 and TGF-ß1, but positively correlated with plasma IL-17A levels. Medical treatment for ITP decreased miR-155 levels. Thus, our results suggest that miR-155 might be involved in the pathogenesis of ITP by regulating cytokine profiles, which may be mediated by miR-155 targeting SOCS1.

Stimuli-triggered growth and removal of a bioreducible nanoshell on nanoparticles.

A new and easy method of stimuli-triggered growth and removal of a bioreducible nanoshell on nanoparticles is reported. The results show that pH or temperature could induce the aggregation of disulfide-contained branched polymers at the surface of nanoparticles; subsequently, the aggregated polymers could undergo intermolecular disulfide exchange to cross-link the aggregated polymers, forming a bioreducible polymer shell around nanoparticles. When these nanoparticles with a polymer shell are treated with glutathione (GSH) or d,l-dithiothreitol (DTT), the polymer shell could be easily removed from the nanoparticles. The potential application of this method is demonstrated by easily growing and removing a bioreducible shell from liposomes, and improvement of in vivo gene transfection activity of liposomes with a bioreducible PEG shell.

Identification of subgroups and development of prognostic risk models along the glycolysis-cholesterol synthesis axis in lung adenocarcinoma.

Lung cancer is one of the most dangerous malignant tumors affecting human health. Lung adenocarcinoma (LUAD) is the most common subtype of lung cancer. Both glycolytic and cholesterogenic pathways play critical roles in metabolic adaptation to cancer. A dataset of 585 LUAD samples was downloaded from The Cancer Genome Atlas database. We obtained co-expressed glycolysis and cholesterogenesis genes by selecting and clustering genes from Molecular Signatures Database v7.5. We compared the prognosis of different subtypes and identified differentially expressed genes between subtypes. Predictive outcome events were modeled using machine learning, and the top 9 most important prognostic genes were selected by Shapley additive explanation analysis. A risk score model was built based on multivariate Cox analysis. LUAD patients were categorized into four metabolic subgroups: cholesterogenic, glycolytic, quiescent, and mixed. The worst prognosis was the mixed subtype. The prognostic model had great predictive performance in the test set. Patients with LUAD were effectively typed by glycolytic and cholesterogenic genes and were identified as having the worst prognosis in the glycolytic and cholesterogenic enriched gene groups. The prognostic model can provide an essential basis for clinicians to predict clinical outcomes for patients. The model was robust on the training and test datasets and had a great predictive performance.

Thermodynamic H-Abstraction Abilities of Nitrogen Centered Radical Cations as Potential Hydrogen Atom Transfer Catalysts in Y-H Bond Functionalization.

Y-H bond functionalization has always been the focus of research interest in the area of organic synthesis. Direct hydrogen atom transfer (HAT) from the Y-H bond is one of the most efficient and practical methods to activate the Y-H bond. Recently, nitrogen centered radical cations were broadly utilized as H-abstraction catalysts to activate Y-H bonds via the HAT process. As a type of HAT catalyst, the H-affinity of nitrogen centered radical cations is a significant thermodynamic parameter to quantitatively evaluate the thermodynamic H-abstraction potentials of nitrogen centered radical cations. In this work, the pK a values of 120 protonated N-containing compounds in acetonitrile (AN) are predicted, and the H-affinities of 120 nitrogen centered radical cations in AN are derived from the reduction potentials of nitrogen centered radical cations and pK a of protonated N-containing compounds using Hess' law. This work focuses on the H-abstraction abilities of 120 nitrogen centered radical cations in AN to enrich the molecule library of novel HAT catalysts or H-abstractors and provides valuable thermodynamic guidelines for the application of nitrogen centered radical cations in Y-H bond functionalization.

Geochemical characteristics and environmental implication of rare earth elements in sediments from the Three Gorges Reservoir, China.

The construction and operation of the Three Gorges Dam occluded sediment transportation in the Yangtze River. However, the sources, transport processes, and environmental impacts of these sediments on the Three Gorges Reservoir (TGR) remain unclear. Here, we used rare earth elements (REEs) to trace the transport pathways of sediments in the TGR, China. Geochemical characteristics including the chemical composition and fractionation, temporal and spatial distribution, and potential sources of REEs were also evaluated in this study. The individual REEs concentration in the TGR sediments followed the Oddo-Harkins rule, with the mean REEs value of 207.33 µg/g. REEs concentrations in the midstream were higher than those in the upstream and downstream of the TGR. Statistical analysis showed that water impoundment phase had no significant influence on the distribution of REEs. TGR sediments are mainly derived from terrigenous detrital particulates, characterized by a distinctive enrichment in light REEs, with its percentage higher than 90 % of the total REEs. The significant positive correlation among the REEs confirmed that they are co-existed and shared the similar sources. Multiple provenance analysis approaches using discriminant function analyses, provenance indices, and La/Yb-La/Sm-Gd/Yb ternary diagrams further indicated that the REEs in sediments originated from the weathering of mudstone in the basin of TGR. After periodic water level fluctuation for more than six years, the chemical compositions of REEs in TGR sediments slightly differed from those of the Yangtze River sediments before TGR construction, but were similar to those of the downstream of the Yangtze River. Therefore, this study indicated that the construction and operation of the TGR changed the chemical compositions and the origin of the sediments in the Yangtze River, which can provide useful insights into the transport pathways of TGR sediments and their impacts on the fluvial environment.

Thermodynamic evaluations of the acceptorless dehydrogenation and hydrogenation of pre-aromatic and aromatic N-heterocycles in acetonitrile.

N-heterocycles are important chemical hydrogen-storage materials, and the acceptorless dehydrogenation and hydrogenation of N-heterocycles as organic hydrogen carriers have been widely studied, with the main focus on the catalyst synthesis and design, investigation of the redox mechanisms, and extension of substrate scope. In this work, the Gibbs free energies of the dehydrogenation of pre-aromatic N-heterocycles (YH2) and the hydrogenation of aromatic N-heterocycles (Y), i.e., ΔGH2R(YH2) and ΔGH2A(Y), were derived by constructing thermodynamic cycles using Hess' law. The thermodynamic abilities for the acceptorless dehydrogenation and hydrogenation of 78 pre-aromatic N-heterocycles (YH2) and related 78 aromatic N-heterocycles (Y) were well evaluated and discussed in acetonitrile. Moreover, the applications of the two thermodynamic parameters in identifying pre-aromatic N-heterocycles possessing reversible dehydrogenation and hydrogenation properties and the selection of the pre-aromatic N-heterocyclic hydrogen reductants in catalytic hydrogenation were considered and are discussed in detail. Undoubtedly, this work focuses on two new thermodynamic parameters of pre-aromatic and aromatic N-heterocycles, namely ΔGH2R(YH2) and ΔGH2A(Y), which are important supplements to our previous work to offer precise insights into the chemical hydrogen storage and hydrogenation reactions of pre-aromatic and aromatic N-heterocycles.

Clinical efficacy and mechanism study of mid-frequency anti-snoring device in treating moderate obstructive sleep apnea-hypopnea syndrome.

BACKGROUND: Obstructive sleep apnea-hypopnea syndrome (OSAHS) is primarily caused by airway obstruction due to narrowing and blockage in the nasal and nasopharyngeal, oropharyngeal, soft palate, and tongue base areas. The mid-frequency anti-snoring device is a new technology based on sublingual nerve stimulation. Its principle is to improve the degree of oropharyngeal airway stenosis in OSAHS patients under mid-frequency wave stimulation. Nevertheless, there is a lack of clinical application and imaging evidence. AIM: To investigate the clinical efficacy and mechanisms of a mid-frequency anti-snoring device in treating moderate OSAHS. METHODS: We selected 50 patients diagnosed with moderate OSAHS in our hospital between July 2022 and August 2023. They underwent a 4-wk treatment regimen involving the mid-frequency anti-snoring device during nighttime sleep. Following the treatment, we monitored and assessed the sleep apnea quality of life index and Epworth Sleepiness Scale scores. Additionally, we performed computed tomography scans of the oropharynx in the awake state, during snoring, and while using the mid-frequency anti-snoring device. Cross-sectional area measurements in different states were taken at the narrowest airway point in the soft palate posterior and retrolingual areas. RESULTS: Compared to pretreatment measurements, patients exhibited a significant reduction in the apnea-hypopnea index, the percentage of time with oxygen saturation below 90%, snoring frequency, and the duration of the most prolonged apnea event. The lowest oxygen saturation showed a notable increase, and both sleep apnea quality of life index and Epworth Sleepiness Scale scores improved. Oropharyngeal computed tomography scans revealed that in OSAHS patients cross-sectional areas of the oropharyngeal airway in the soft palate posterior area and retrolingual area decreased during snoring compared to the awake state. Conversely, during mid-frequency anti-snoring device treatment, these areas increased compared to snoring. CONCLUSION: The mid-frequency anti-snoring device demonstrates the potential to enhance various sleep parameters in patients with moderate OSAHS, thereby improving their quality of life and reducing daytime sleepiness. These therapeutic effects are attributed to the device's ability to ameliorate the narrowing of the oropharynx in OSAHS patients.

High arsenic pollution of the eutrophic Lake Taihu and its relationship with iron, manganese, and dissolved organic matter: High-resolution synchronous analysis.

Arsenic (As) is a metalloid that can accumulate in eutrophic lakes and cause adverse health effects to people worldwide. However, the seasonal process and dynamic mechanism for As mobilization in eutrophic lake remains effectively unknown. Here we innovatively used the planar optodes (PO), high-resolution dialysis (HR-Peeper) combined with fluorescence excitation-emission matrix coupled with parallel factor (EEM-PARAFAC) analysis technologies. We synchronously investigate monthly O2, As, iron (Fe), manganese (Mn), and naturally occurring dissolved organic matter (DOM) changes in sediments of Lake Taihu at high resolution in field conditions. We find high As contamination from sediments with 61.88-327.07 µg m-2 d-1 release As fluxes during the algal bloom seasons from May to October 2021. Our results show that an increase in DOM, mainly for humic-like components, resulting in high electron transfer capacity (ETC), promoted the reductive dissolution of Fe and Mn oxides to release As. Partial least square-path modeling (PLS-PM) and random forest modeling analysis identified that Mn oxide reductive dissolution directly accelerated sediments As contamination, which is the crucial factor. Understanding crucial factor controlling As release is especially essential in areas of eutrophic lakes developing effective strategies to manage As-rich eutrophic lake sediments worldwide.

Characterization of the CMS genetic regulation through comparative complete mitochondrial genome sequencing in Nicotiana tabacum.

Mitochondrial genomes (mitogenomes) of flowering plants vary greatly in structure and size, which can lead to frequent gene mutation, rearrangement, or recombination, then result in the cytoplasmic male sterile (CMS) mutants. In tobacco (Nicotiana tabacum), suaCMS lines are widely used in heterosis breeding; however, the related genetic regulations are not very clear. In this study, the cytological observation indicated that the pollen abortion of tobacco suaCMS(HD) occurred at the very early stage of the stamen primordia differentiation. In this study, the complete mitochondrial genomes of suaCMS(HD) and its maintainer HD were sequenced using the PacBio and Illumina Hiseq technology. The total length of the assembled mitogenomes of suaCMS(HD) and HD was 494,317 bp and 430,694 bp, respectively. Comparative analysis indicated that the expanded 64 K bases in suaCMS(HD) were mainly located in noncoding regions, and 23 and 21 big syntenic blocks (>5000 bp) were found in suaCMS(HD) and HD with a series of repeats. Electron transport chain-related genes were highly conserved in two mitogenomes, except five genes (ATP4, ATP6, COX2, CcmFC, and SDH3) with substantial substitutions. Three suaCMS(HD)-specific genes, orf261, orf291, and orf433, were screened. Sequence analysis and RT-PCR verification showed that they were unique to suaCMS(HD). Further gene location analysis and protein property prediction indicated that all the three genes were likely candidates for suaCMS(HD). This study provides new insight into understanding the suaCMS mechanism and is useful for improving tobacco breeding.

Newly developed TGF-ß2 knock down transgenic mouse lines express TGF-ß2 differently and its distribution in multiple tissues varies.

BACKGROUND: Transforming growth factor-betas (TGF-ßs), including beta2 (TGF-ß2), constitute a superfamily of multifunctional cytokines with important implications in morphogenesis, cell differentiation and tissue remodeling. TGF-ß2 is thought to play important roles in multiple developmental processes and neuron survival. However, before we carried out these investigations, a TGF-ß2 gene down-regulated transgenic animal model was needed. In the present study, expressional silencing TGF-ß2 was achieved by select predesigning interference short hairpin RNAs (shRNAs) targeting mouse TGF-ß2 genes. RESULTS: Four homozygous transgenic offspring were generated by genetic manipulation and the protein expressions of TGF-ß2 were detected in different tissues of these mice. The transgenic mice were designated as Founder 66, Founder 16, Founder 53 and Founder 41. The rates of TGF-ß2 down-expression in different transgenic mice were evaluated. The present study showed that different TGF-ß2 expressions were detected in multiple tissues and protein levels of TGF-ß2 decreased at different rates relative to that of wild type mice. The expressions of TGF-ß2 proteins in transgenic mice (Founder 66) reduced most by 52%. CONCLUSIONS: The present study generated transgenic mice with TGF-ß2 down-regulated, which established mice model for systemic exploring the possible roles of TGF-ß2 in vivo in different pathology conditions.

Thermodynamic Evaluations of Amines as Hydrides or Two Hydrogen Ions Reductants and Imines as Protons or Two Hydrogen Ions Acceptors, as Well as Their Application in Hydrogenation Reactions.

Since the hydrogenation of imines (X) and the dehydrogenation of amines (XH2) generally involve the two hydrogen ions (H- + H+) transfer, the thermodynamic abilities of various amines releasing hydrides or two hydrogen ions as well as various imines accepting protons or two hydrogen ions are important and characteristic physical parameters. In this work, the pKa values of 84 protonated imines (XH+) in acetonitrile were predicted. Combining Gibbs free energy changes of amines releasing hydrides in acetonitrile from our previous work with the pKa(XH+) values, the Gibbs free energy changes of amines releasing two hydrogen ions and imines accepting two hydrogen ions were derived using Hess's law by constructing thermochemical cycles, and the thermodynamic evaluations of amines as hydrides or two hydrogen ions reductants and imines as protons or two hydrogen ions acceptors are well compared and discussed. Eventually, the practical application of thermodynamic data for amines and imines on hydrogenation feasibility, mechanism, and possible elementary steps was shown and discussed in this paper from the point of thermodynamics.