Ts2O Promoted Deoxygenative C-H Dithiocarbonation of Quinoline N-Oxides with Potassium O-Alkyl Xanthates.

A simple, efficient, and practical method for the synthesis of S-quinolyl xanthates was developed via Ts2O-promoted deoxygenative C-H dithiocarbonation of quinoline N-oxides with various potassium O-alkyl xanthates. The reaction performed well under transition-metal-free, base-free, and room-temperature conditions with wide substrate tolerance. Employing potassium O-tert-butyl xanthate (tBuOCS2K) as a nucleophile, some valuable quinoline-2-thiones were unexpectedly obtained in a one-pot reaction without any additional base.

Persulfate-Promoted Carbamoylation/Cyclization of Alkenes: Synthesis of Amide-Containing Quinazolinones.

The incorporation of amide groups into biologically active molecules has been proven to be an efficient strategy for drug design and discovery. In this study, we present a simple and practical method for the synthesis of amide-containing quinazolin-4(3H)-ones under transition-metal-free conditions. This is achieved through a carbamoyl-radical-triggered cascade cyclization of N3-alkenyl-tethered quinazolinones. Notably, the carbamoyl radical is generated in situ from the oxidative decarboxylative process of oxamic acids in the presence of (NH4)2S2O8.

Ball milling synthesis of S-quinolyl xanthates via coupling of haloquinolines with potassium O-alkyl xanthates.

An environmentally benign protocol that provides various S-quinolyl xanthates via a ball milling enabled cross coupling reaction of haloquinolines and readily available potassium O-alkyl xanthates is first reported. The reaction proceeded well under mild, transition metal- and solvent-free conditions, making it an attractive method for the introduction of xanthates into the quinoline scaffold.

Theoretical study on ferroelectric nitrides with super-wurtzite structures for solar energy conversion applications.

Polarized structured nitride semiconductors are attractive due to their unique and environment-friendly electronic properties. The stability, ferroelectricity and photocatalytic and photovoltaic properties of super-wurtzite Mg2XN3 (X = Bi, Mo, Nb, Sb, Ta, Tc and W) were determined based on first principles calculations in this study. The calculated results indicate that Mg2XN3 (X = Sb, Ta, Bi and Nb) are stable polar nitrides by phonon frequencies, elastic coefficients and ferroelectric analysis. Mg2XN3 (X = Sb, Ta and Nb) with large ferroelectric polarization strength could absorb ultraviolet light to promote photocatalytic water splitting for hydrogen production. Mg2BiN3 is a new excellent photovoltaic candidate due to its ideal energy band, high electron mobility, high absorption coefficient and large ferroelectric polarization strength.

Prevalence and prognosis of hard-to-heal wounds with comorbidities in China.

OBJECTIVE: Regular retrospective analysis is necessary for potential improvement in clinical practice for the treatment of hard-to-heal wounds. Comorbidities and outcomes have demonstrated spatial and temporal diversity, emphasising the importance of updates in epidemiology. The complexity of healing hard-to-heal wounds has long been known, and so we sought evidence-based improvement on the current principles of treatment. METHOD: Demographic and clinical information of patients from the WoundCareLog database was collected. Patients who met the inclusion criteria and completed follow-up after treatment were included. Comorbidities were diagnosed and classified into eight categories based on ICD-10. We compared the demographic and aetiological characteristics between patients with and without comorbidities by t-test and Chi-squared test. The impact of comorbidities on wound healing were evaluated with a multivariate Cox model. RESULTS: A total of 2163 patients met the inclusion criteria and were enrolled, of whom 37.0% were aged 61-80 years, 36.0% were aged 41-60 years and 60.8% were male. The lower extremities and buttocks were the most commonly affected areas with hard-to-heal wounds. Non-traumatic wounds accounted for 66.6% of cases, and infection, pressure and diabetes were the most common causes. Paralysis and diabetes were the most important factors which led to a prolonged healing process and inferior clinical outcomes. CONCLUSION: Comorbidities of hard-to-heal wounds were treated as separate contributors and their weighted effect on outcome was calculated through correlation analysis. Paralysis and diabetes were the most unfavourable comorbidities affecting the treatment of non-traumatic hard-to-heal wounds. Our study highlighted the priority of comorbidity treatment through data-driven approaches. It provides potential value in developing better public health strategies and preventive medicine.

WoundCareLog APP - A new application to record wound diagnosis and healing.

The incidence of chronic wounds has been increasing over the past 20 years. However, the standardized diagnosis and treatment practice of chronic refractory wounds have not been established. In addition, the properties of the wound are characterized by morphology and thus correct description of the wound in medical history collection plays a vital role, which directly affects the definitive diagnosis. To develop more accurate format of clinical history record which can correctly reflect a patient's course and treatment progress, and to standardize the medical history record of chronic refractory wounds, at the national or regional level, we designed the WoundCareLog APP. It acts as a recording and communication tool for wound healing specialists at all levels of medical institutions in China. The WoundCareLog APP is fully compatible to meet the criteria and requirements of conventional medical records by embedding 9 modules. In addition, the demands for morphological description of wounds in wound healing diagnosis and treatment have been fulfilled by enroll of digital imaging technology to overcome the inadequacies of traditional medical history records.

Tenuigenin promotes the osteogenic differentiation of bone mesenchymal stem cells in vitro and in vivo.

Osteoporosis, which is a systemic skeletal disease characterized by low bone mineral density and microarchitectural deterioration of bone quality, is a global and increasing public health problem. Recent studies have suggested that Tenuigenin (TEN), a class of native compounds with numerous biological activities such as anti-resorptive properties, exerts protective effects against postmenopausal bone loss. The present study aims to investigate the osteogenic effects of TEN on bone mesenchymal stem cells (BMSCs) in vitro and in vivo. Alkaline phosphatase (ALP) activity/staining, Alizarin red staining and the expression of osteogenic markers, including runt-related transcription factor 2, osterix, osteocalcin, collagen Iα1, ß-catenin and glycogen synthase kinase-3ß were investigated in primary femoral BMSCs from C57/BL6 mice cultured under osteogenic conditions for 2 weeks to examine the effects of TEN. An ovariectomized (OVX) mouse model was used to investigate the effect of TEN treatment for 3 months in vivo. We found that ALP activity, mineralized nodules and the expression of osteogenic markers were increased and WNT/ß-catenin signaling was enhanced in vitro and in vivo. Bone parameters, including trabecular thickness, trabecular number and bone mineral density were higher in the OVX+TEN group than in control OVX mice. Our results suggest the therapeutic potential of TEN for the treatment of patients with postmenopausal osteoporosis.

High-coverage stable structures of 3d transition metal intercalated bilayer graphene.

Alkali-metal intercalated graphite and graphene have been intensively studied for decades, where alkali-metal atoms are found to form ordered structures at the hollow sites of hexagonal carbon rings. Using first-principles calculations, we have predicted various stable structures of high-coverage 3d transition metal (TM) intercalated bilayer graphene (BLG) stabilized by the strain. Specifically, with reference to the bulk metal, Sc and Ti can form stable TM-intercalated BLG without strain, while the stabilization of Fe, Co, and Ni intercalated BLG requires the biaxial strain of over 7%. Under the biaxial strain ranging from 0% to 10%, there are four ordered sandwich structures for Sc with the coverage of 0.25, 0.571, 0.684, and 0.75, in which the Sc atoms are all distributed homogenously instead of locating at the hollow sites. According to the phase diagram, a homogenous configuration of C8Ti3C8 with the coverage of 0.75 and another inhomogeneous structure with the coverage of 0.692 were found. The electronic and magnetic properties as a function of strain were also analyzed to indicate that the strain was important for the stabilities of the high-coverage TM-intercalated BLG.

Theoretical study on the stability, ferroelectricity and photocatalytic properties of CaBiO3.

Materials with high ferroelectric polarization strength and sufficient absorption of visible light have unique advantages in photocatalysis. Based on the results of structure search, phonon frequency, and elasticity coefficient calculations, CaBiO3 has a stable R3 polar structure. First-principles calculations indicate that R3-CaBiO3 is a potentially efficient ferroelectric visible-light photocatalytic material for hydrogen production. CaBiO3 under slight strain can maintain high ferroelectric polarization strength, strong visible light absorption capacity and small effective mass. CaBiO3 under tensile strain has potentially ferroelectric photogeneration of hydrogen with a band edge position that crosses the redox potential of water. These results can expand the application of Bi-based materials in photocatalytic hydrogen production.

Theoretical study on the ferroelectric and light absorption properties of Li2SbBiO6 for harvesting visible light.

Ferroelectric oxides with large bandgaps have restricted applications in photovoltaic and photocatalytic fields. Based on recent experiments with the ferroelectric compound, LiSbO3, the stability and optoelectronic properties of a new ferroelectric compound, namely Li2SbBiO6, are investigated in this study. The calculated results demonstrate that Li2SbBiO6 satisfies the stability conditions of the elastic coefficients and phonon dynamics. Li2SbBiO6 maintains the ferroelectric polarization strength of LiSbO3 and significantly reduces the bandgap, and thus has been explored for applications in photovoltaic and photocatalytic fields. Li2SbBiO6 is a new potential ferroelectric oxide for harvesting visible light owing to its suitable bandgap and a large hole-electron effective mass ratio.

[Pollution Characteristics and Ecological Risk Assessment of Organochlorine Pesticides in Water Source Areas of Guangdong and Guangxi].

The concentrations of 16 organochlorine pesticides (OCPs) in 7 water samples collected from different sites of water source areas of Guangdong and Guangxi were detected by SPE-GC-MS, and then the pollution characteristics were analyzed. This study established species sensitivity distribution(SSD) curves with BurrⅢ distribution model. In the meantime, HC5 values were calculated by BurrliOZ software, which were used to evaluate the toxicity effects of OCPs towards aquatic organisms. Finally, margin of safety concentration values were calculated to assess the ecological risk. The results showed that the concentration of OCPs varied from 6.64 to 34.19 ng·L-1, with a mean value of 16.76 ng·L-1, while HCHs and DDTs contributed a lot. HCHs were predominately originated from lindane, which is a component in household insecticide, while DDTs were from dicofol contamination or historical residues. Vertebrates could stand severer toxicity in comparison with invertebrates. α-endosulfan showed a greater toxicity towards aquatic plants and microorganisms than others, while p, p'-DDT turned out to be the most hazardous pollutant to vertebrates and invertebrates among the 16 OCPs studied. Generally speaking, OCPs in study areas didn't show conspicuous ecological risks towards aquatic organisms, DDTs and α-endosulfan, however, are still worth paying close attention due to their high potential risks.

Regulation of bone formation by baicalein via the mTORC1 pathway.

Osteoporosis is a systemic skeletal disease that is characterized by low bone density and microarchitectural deterioration of bone tissue. The increasing prevalence of osteoporosis has attracted much attention. In this study, MC3T3-E1 pre-osteoblasts were treated with the natural compound, baicalein (0.1 µmol/L, 1 µmol/L, 10 µmol/L), to stimulate differentiation over a 14-day period. In addition, a canonical ovariectomized (OVX) mouse model was used to investigate the effect of 3-month baicalein treatment (10 mg/kg per day) in preventing postmenopausal osteoporosis. In vitro, we found that baicalein induced activation of alkaline phosphatase, stimulated the mammalian target of rapamycin complex 1 (mTORC1) signaling pathway, and induced expression of osteoblast differentiation markers, ie, osteocalcin, osterix, collagen Iα1, and runt-related transcription factor 2 (RUNX2), in osteoblasts. In vivo, several bone parameters, including trabecular thickness, trabecular bone mineral density, and trabecular number, in the distal femoral metaphysis were significantly increased in OVX mice treated intragastrically with baicalein for 3 months compared with OVX mice that were not treated with baicalein. We also found that expression of osteocalcin and RUNX2 was decreased in primary ossified tissue from the OVX group, and baicalein increased the levels of osteocalcin and RUNX2 in OVX mice. These data suggest that baicalein can stimulate MC3T3-E1 cells to differentiate into osteoblasts via activation of the mTORC1 signaling pathway, which includes protein kinases and transcription factors such as P-4E/BP1 and P-S6K1.

[Drug-resistance Acinetobacter baumannii infection in burn patients: current situation and countermeasure].

Infections caused by Acinetobacter baumannii (AB) have emerged as a knotty clinical problem in the burn wards due to its omni-resistance to antibiotics and high prevalence. Although our knowledge in regard to the pathogenesis and the resistance mechanisms of AB is increasing, the available treatment remains much limited. Measures to effectively control nosocomial infection are warranted. Meanwhile, development of novel therapeutic agents or combination of antibiotics should be considered.

[Effect of different immunomodulation on inflammatory response in burn rats with sepsis].

OBJECTIVE: To investigate the effect of Thymosin and growth hormone(GH) on inflammatory response in burn rats or burn rats with sepsis. METHODS: Sixty-four SD rats were randomly divided into normal control group (NC, without treatment), sepsis group (S, with injection of LPS), sepsis + Thymosin group (ST, with successive injection of Thymosin and LPS), sepsis + GH group [SGH, with successive injection of recombinant human GH (rhGH) and LPS], burn group, burn + sepsis group (BS, with injection of LPS after burn), burn + sepsis + Thymosin group (BST, with successive injection of Thymosin and LPS after burn), burn + sepsis + GH (BSGH, with successive injection of rhGH and LPS after burn), with 8 rats in each group. Specimens of spleen tissues were harvested to determine HLA-DR in lymphocyte and evaluate inflammatory cell infiltration (score). Specimens of peripheral blood were collected to determine Toll-like receptor 4 (TLR4) level in monocyte and serum level of TNF-alpha, IL-4, IL-6, IL-10. RESULTS: Compared with those in NC group, serum level of IL-10 in S group decreased obviously, while other indices increased obviously (P < 0.01). The levels of HLA-DR and TLR4 and serum level of TNF-alpha were similar between SGH and ST groups (P > 0.05). Compared with those in SGH group [(2.87 +/- 0.04) score, and IL-6 (0.0083 +/- 0.0018) microg/mg, IL-4 (0.0102 +/- 0.0021) microg/mg, IL-10 (0.0310 +/- 0.0027) microg/mg, respectively], degree of inflammatory cell infiltration (1.50 +/- 0.76) score and serum levels of IL-6, IL-4, IL-10 of rats in ST group decreased obviously (0.0064 +/- 0.0012, 0.0058 +/- 0.0024, 0.0230 +/- 0.0021 microg/mg, respectively, P < 0.01). The levels of HLA-DR, TLR4 and inflammatory cell infiltration degree of spleen in B group were respectively higher than those in NC group and lower than those in BS group. Compared with those in NC group, serum levels of TNF-alpha, IL-6 in B group increased significantly, while IL-4, IL-10 showed an opposite tendency. There was no obvious difference between BST and BSGH groups in serum levels of HLA-DR and IL-6 (P > 0.05). Compared with those in BST group, inflammatory cell infiltration degree in spleen and the levels of TLR, TNF-alpha obviously decreased (P < 0.01), while IL-4 and IL-10 levels increased in BSGH group (P < 0.01). CONCLUSIONS: Inhibitive effects between Thymosin and GH on extensive inflammatory reaction were similar with or without trauma, and GH has better effect as compared with Thymosin when with trauma.