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Microplastics (MPs) ingested and accumulated by organisms would ultimately pose a threat to humans via food chain. A balanced gut microbiota contributes to many health benefits, which is readily to be influenced by environmental chemicals such as MPs. Cyanidin-3-glucoside (C3G), a bioactive compound of anthocyanin family, possesses a variety of functional effects including anti-oxidant and anti-inflammatory, as well as gut microbiota modulation. C3G has been demonstrated to prevent polystyrene (PS) induced toxicities in Caco2 cells and Caenorhabditis elegans (C. elegans) via activating autophagy and promoting discharge. In the present study, we aimed to explore the alleviation effect of C3G on PS induced toxicities in C57BL/6 mice. Our results show that the supplementation of C3G effectively reduced tissue accumulation and promoted fecal PS discharge, leading to alleviated PS-caused oxidative stress and inflammatory response. Meanwhile, C3G modulated PS-associated gut microbiome perturbations and regulated functional bacteria in inflammation such as Desulfovibrio, Helicobacter, Oscillospiraceae and Lachnoclostridium. Also, C3G administration initiated alterations in functional pathways in response to xenobiotic PS, and reduced bacterial functional genes related to inflammation and human diseases. These findings may offer evidence on the protective role of C3G for the intervention of PS-induced toxicity and gut dysbiosis.

Effective nutrient transport and appropriate mechanical stimulation play important roles in production of tissue-engineered bone grafts. In this study, an experimental set-up for magnetic-driven dynamic culture of cells was designed to mimic the microenvironment of the bone tissue. Here, its ability to contribute to osteogenic differentiation was investigated by inoculating human umbilical cord mesenchymal stem cells (HUMSCs) on magnetic scaffolds. The cytocompatibility of the developed magnetic scaffolds was verified for HUMSCs. Magnetic scaffolds seeded with HUMSCs were exposed to magnetic fields. The results showed that magnetic fields did not affect cell activity and promoted HUMSCs osteogenic differentiation. The magnetic scaffolds were magnetically driven for dynamic culture in the experimental set-up to evaluate the influence of HUMSCs osteoblast differentiation. The results indicated that magnetic-driven dynamic culture increased cell alkaline phosphatase (ALP) activity (p p

Type 2 diabetes mellitus is a disease associated with an oxidative milieu that often leads to adverse health outcomes. Multiple anthocyanins have been reported to possess outstanding antioxidant activity, however, their effects on hyperglycemia-related oxidative stress remain elusive. In the present study, cyanidin-3-O-glucoside (C3G), a typical anthocyanin with various widely accepted health benefits, was applied to alleviate oxidative stress in pancreas islets under the conditions of hyperglycemia. Firstly, significantly decreased mitochondrial membrane potential (MMP) and antioxidant enzymes, as well as increased reactive oxygen species (ROS) and O2- levels, were detected after exposure to a series of concentrations of high glucose (HG) and palmitic acid (PA), which manifested oxidative stress triggered by mitochondrial damage. To evaluate the antioxidant effect of C3G in vitro, the islet cell line NIT-1 was used, and results proved that C3G could effectively relieve cellular oxidative stress induced by HG and PA. Furthermore, we found that the antioxidant effect of C3G was achieved by activating mitophagy via the PINK1-PARKIN signaling pathway. More importantly, an autophagy inhibitor chloroquine (CQ) was added to verify our findings at the protein level, and we observed the co-localization of mitochondria and lysosomes, which may form autophagolysosomes to clean damaged mitochondria. Immediately afterwards, more studies were conducted on pancreatic islets of diabetic db/db mice to verify the antioxidant effect of C3G discovered in islet cells. Along with the decline in fasting blood glucose, the oxidative stress in pancreas islets was successfully alleviated in diabetic db/db mice after supplementation with C3G. This was demonstrated by increased levels of ROS, and the impaired activities of anti-oxidative enzymes superoxide dismutase (SOD) and catalase (CAT) were partly reversed by C3G intervention. Our study has provided evidence for the alleviation effect of C3G against oxidative stress in pancreas islets, which may provide enlightenment for improving the health situation of diabetic patients in the future.

Tetrastigma hemsleyanum is traditionally used as a folk medicine and functional food in China. Its extracts have been confirmed to have many bioactivities. However, the effect of extracting temperature on its bioactivity has not been reported. In this research, the total flavonoids content (TFC), total polyphenol content (TPC), antiproliferative, antioxidant, and anti‐inflammatory activities of ethanol extracts and water extracts (extracted at 55, 70, 85, and 100°C) were observed. The results indicated that ethanol extracts showed better antioxidant activity with DPPH EC50 of 504.1 ± 3.8 μg/ml and ABTS EC50 of 851.4 ± 3.9 μg/ml. A better antiproliferative activity on HepG2, PC12, Caco‐2, and Hela cells was observed on ethanol extracts. The results of anti‐inflammatory activities also indicated that all of the extracts can reduce the NO production of LPS‐stimulated macrophage with dose‐independent manner. In summary, the results showed that the antiproliferative, antioxidant, and anti‐inflammatory activities of water extracts decreased with the increasing temperature to some extent.

The brown planthopper (BPH), Nilaparvata lugens (Homoptera: Delphacidae), is a kind of seriously pest of rice crops throughout Asia and effective control is essential for economical crop production. Insecticides Abamectin, Imidacloprid, Chlorantraniliprole, Phoxim and Chlorpyrifos have been broadly used to control the brown planthopper for recent years. To investigate the resistance development of the BPH in Guizhou Province, we collected BPH from 5 sites (Panxian, Jinping, Sandu, Daozhen and Huaxi) in Guizhou Province June–August 2014. Their responses to two diagnostic doses of 5 insecticides (LD50 and detoxification enzyme activity) were examined. The results showed that LD50 value for Chlorantraniliprole in Jinping and Huaxi BPH population were 199.810 and 282.082 μg/g higher than imidacloprid, phoxim and chlorpyrifos. LD50 value for Imidacloprid in Jinping population was 3.957 μg/g lower than other BPH populations for 4 insecticides. The GSTs activity is significantly higher with Abamectin, Chlorpyrifos and Phoxim treatments. AchE activity is higher with Chlorantraniliprole and Imidacloprid, but lowest among three enzymes with Phoxim and Chlorpyrifos. The data demonstrate the development and spread of multiple resistance in N. lugens in Guizhou Province and support reports of reduced field efficacy of imidacloprid.

Since flavonoids are antioxidant compounds, they could beneficially affect neurodegenerative diseases where reactive oxygen species are involved. In this study, we firstly isolated and identified fourteen compounds from the flowers of Apios americana Medik. Then, we tested whether Apios americana Medik flowers water extract (AFWE) exerts a protective effect on H2O2 induced PC12 cells injure. As expected, pretreatment with AFWE inhibited cytotoxicity and DNA condensation in H2O2induced PC12 cells. Exposure of PC12 cells to H2O2 resulted in reactive oxygen species accumulation and mitochondrial dysfunction, while AFWE alleviated these damages. AFWE obviously reversed the alternations as H2O2 increased Caspase-3 and decreased the ratio of Bcl-2/Bax expressions. Furthermore, autophagy in PC12 cells was further activated by AFWE, which was beneficial to resisting adversity. These results manifest that AFWE prevents H2O2 induced damage via regulating autophagy.

Background Circulating cell-free DNA (cfDNA) detection for non-invasive diagnosis requires higher sensitivity and accuracy due to the low circulating tumor DNA (ctDNA) content. Many methods have been developed to improve detection of ctDNA, including ultra-deep sequencing or enrichment of shorter cfDNA fragments, such as those in the range of 90-150 bp. Methods Here, we developed a method for single-stranded DNA (ssDNA) library preparation with a large proportion of magnetic beads to enrich the shorter cfDNA fragments. We aimed to determine if this could increase the ctDNA content and thus improve the sensitivity of ctDNA detection by testing the method in blood samples from patients with advanced cancers (non-small cell lung cancers, esophageal squamous cell carcinoma, cholangiocarcinoma, colorectal cancer and liver cancer). Results This method was able to obtain shorter cfDNA both in commercial cfDNA references and real world clinical cfDNA samples. Plasmid simulation experiments showed that using a large proportion of magnetic beads to construct the library could obtain more ctDNA derived from shorter-fragment plasmids, which could significantly improve the detection of ctDNA especially in the low-variant allele frequency sample. In real-world clinical samples, this method may be able to increase the opportunity to obtain alteration reads from short fragments, which was important to low frequency detection. Conclusions The ssDNA library preparation with large proportion of magnetic beads could increase the opportunity to obtain alteration reads from short fragments, which is crucial for low variant allele frequency detection.

Increasing attention has been brought to microplastics pollution recently, while emerging evidences indicate that nano-plastics degraded from microplastics are more of research significance owing to stronger toxicity. However, there is little study focused on the prevention of nano-plastics induced toxicity until now. Canidin-3-glucoside (C3G), a natural anthocyanin proved to possess multiple functions like antioxidant and intestinal tissue protection. Thus, we proposed whether C3G could act as a molecular weapon against nano-plastics induced toxicity. In Caco2 cell and Caenorhabditis elegans (C. elegans) models, we found that polystyrene (PS) nano-plastics exposure resulted in physiological toxicity and oxidative damage, which could be restored by C3G. More significantly in Caco2 cells, we observed that autophagy was activated via Sirt1-Foxo1 signaling pathway to attenuate PS induced toxicity after C3G intervention and further verified by adding autophagy inhibitor 3-Methyladenine (3-MA). Meanwhile, PS co-localization with lysosomes was observed, indicating the encapsulation and degradation of PS. In C. elegans, by detecting LGG-1/LC3 expression in GFP-targeted LGG-1 report gene (LGG-1:GFP) labeled transgenic DA2123 strain, the co-localization of LGG-1:GFP with PS was found as well, means that autophagy is involved in C3G’s beneficial effects. Furthermore, we were surprised to find that C3G could promote the discharge of PS from N2 nematodes, which reduces PS toxicity more directly.

Industrialization of perovskite solar cells is constrained by adverse stability in the air. Herein, we report effective strontium chloride (SrCl2) passivation upon HC(NH2)2–CH3NH3 (FA–MA)-based perovskite thin films for the suppression of nonradiative recombination. Moreover, the recombination dynamics, crystallinity, carrier transport, morphology, and the elemental stoichiometry of this film were systematically studied. By optimizing the concentration of SrCl2, the corresponding devices exhibited an increased open-circuit voltage (1.00 V vs 1.09 V), consistent with the enhanced photoluminescence lifetime. The champion passivated device showed an ascendant power conversion efficiency (PCE) about 21.11%, with over 90% retention of the primal PCE in dry air after 1000 h of aging with 20–30% humidity. A superior stability and an accelerated electron/hole-extraction ability were further observed by time-resolved photoluminescence spectroscopy.

Acrylamide (ACR), as a raw material of polyacrylamide that used in water purification, was verified to possess various toxicity. Tetrastigma hemsleyanum (TH) is a medicinal plant widely used to anti-inflammation and anti-tumor in Chinese folks. However, more researches focused on the biological activities in tubers and the leaves were ignored. Thus, the protective effect of Tetrastigma hemsleyanum leaves extract (THLE) against ACR-induced toxicity in HepG2 cells and Caenorhabditis elegans (C. elegans) was explored in this study. In vitro, we observed that THLE attenuated ACR-induced toxicity in HepG2 cell via regulating Akt/mTOR/FOXO1/MAPK signaling pathway. Further research proved that 5-caffeoylquinic acid (5-CA) plays a major role in THLE's amelioration effect of ACR toxicity. In vivo, it was found that THLE possesses the same protective effect in ACR-treated wild-type N2 C. elegans and daf-2 (-) (deficit in DAF-2) mutants. However, the anti-ACR toxicity effect of THLE in daf-16 (-) mutants (deficit in DAF-16 that homologous to FOXO family in human) was weakened. Our results indicated that THLE exhibited protective effects against ACR-induced toxicity both in HepG2 cells and C. elegans, while DAF-16/FOXO gene is involved in THLE' protective effect via regulating the expression levels of downstream antioxidant genes.

In this work, we report a novel two-dimensional (2D) (SrBr)2PbI4perovskite layered architecture, which were formed by the reaction of strontium bromide (SrBr2), strontium iodide (SrI2) and lead iodide (PbI2). Formation of 2D (SrBr)2PbI4was verified by small angle XRD peak at 6.4°, which corresponds to the layer distance of 13.78 A. The best one of solar cells fabricated with Quasi-3D perovskite, (SrBr)2FA59Pb60I181(n= 60), showed a power conversion efficiency (PCE) of 18.46% and retained 95% of the initial PCE at 1000 h in the dry air. Further, the 2D (SrBr)2PbI4as the surface passivation layer on the 3D FAPbI3perovskite greatly reduced the defects at the perovskite/Spiro-OMeTAD interface, and the corresponding solar cells with FAPbI3/(SrBr)2PbI43D/2D structure achieved a PCE of 22.14% and over 90% retention of the original PCE at 1000 h. In short, this work provides an example of inorganic complex cations that can form 2D perovskites and achieve perovskite solar cells with high PCE and stabilization at the same time.

The structures of microsolvated (LiI) 2 − (H 2 O) n (n = 0–6) clusters and their corresponding neutrals were determined using ab initio calculations. One Li-I distance in (LiI) 2 − (H 2 O) n abruptly increases at n = 5, thus a I atom is firstly seperated out from the (LiI) 2 − unit. For the neutrals, the notable elongation of Li-I distances occurs at n = 4, and a I atom prefer to leave the (LiI) 2 unit. The charge analyses show that the excess electrons mainly localizes on the terminal Li atom for (LiI) 2 − (H 2 O) 0-1 , whereas charge transfer to water occurs when the number of water reaches 2. The RDG analyses show that Li + -water interactions are dominant, and with the increase of water molecules, the I − -water and water-water interactions are considerably enhanced. The comparison of (LiI) 2 − (H 2 O) n and (MI) 2 − (H 2 O) n (M = Na, K) indicates that (LiI) 2 − is more difficult to be pried apart than (MI) 2 − .

Tetrastigma hemsleyanum Diels et Gilg, a rare herbal plant native to China, possesses high medicinal value. More researches have focused on the flavones in the tubers of Tetrastigma hemsleyanum whereas polysaccharides attract few attentions. In this study, a purified polysaccharide (TTP-1) with the average molecular weights of 478.33 kDa was extracted from Tetrastigma hemsleyanum and conducted multiple analysis to identify its structural information. In vitro, TTP-1 could suppress the inflammation, cytotoxicity, genotoxicity, mitochondrial dysfunction and oxidative damage induced by LPS in RAW264.7 cells. Meanwhile, TTP-1 could attenuate inflammation via COX-2, iNOS, MAPKs pathways and ameliorate oxidative damage through Nrf2-Keap1, Sirt1-FoxO1 pathways in RAW264.7 cells. In vivo, the inflammation induced by LPS triggered the suppression of survival ratio and growing development, as well as the restrain of athletic ability in Caenorhabditis elegans. The treatment of TTP-1 reversed the situation induced by LPS. In a word, TTP-1 could ameliorate LPS-induced inflammation both in vitro and in vivo.

Ethyl Carbamate (EC), as a carcinogen widely found in fermented foods, was verified that its cytotoxicity was associated with oxidative stress. Polysaccharides from natural sources due to their antioxidative capacity have attracted great attention in the past time. In this study, purified polysaccharide from Tetrastigma hemsleyanum vines (TVP) with 64.89 kDA was extracted and conducted multiple analysis to identify its structural information. It could be discovered that TVP was composed of mannose, rhamnose, glucuronic acid, glucose, galactose, and arabinose. In vitro, TVP could inhibit cytotoxicity and genotoxicity, attenuate oxidative damage and mitochondrial dysfunction induced by EC in Caco-2 cells. Meanwhile, TVP could suppress apoptosis by mTOR and Bcl-2 signaling pathways, ameliorate oxidative via Sirt1-FoxO1 and Nrf2-Keap1 signaling pathways. In vivo, EC as well triggered the decline of survival and athletic ability in Caenorhabditis elegans (C. elegans) and TVP could reverse the decline. In the meantime, TVP could ameliorate oxidative damage in N2 and daf-2 (-) mutant but fail in daf-16 (-) mutant, which suggested that DAF-16 (FOXO) might affect the antioxidative protection of TVP in C. elegans. In brief, our results manifested that TVP could attenuate EC-induced cytotoxicity both in vitro and in vivo.

The main flavonoid components of Radix Tetrastigma (RTF) were extracted and identified by UPLC-TOF/MS. In vitro, RTF prevented inflammation in RAW 264.7 cells by suppressing morphological (both cell and nucleus) changes, and decreasing nitric oxide (NO), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) contents. Exposure to LPS also leads to oxidant damage, and RTF alleviated damage to mitochondria, decreased O2- accumulation, and restored the glutathione level. RTF intervention decreased the expression of c-Jun N-terminal kinase (JNK) and p38 phosphorylation, accompanied by downregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and forkhead box protein O1 (FoxO1). In vivo, aging of Caenorhabditis elegans (C. elegans) by paraquat (PQ) was observed through lifespan, lipofuscin, and enzyme analysis. RTF protected against damage in N2 worms but not in daf-16 mutants. Gene expression was further assessed, and p38/PMK-1 and Nrf2/SKN-1 expression in worms was suppressed by PQ, which was reversed by RTF treatment. Together, these results suggested that RTF could help ameliorate inflammation-induced damage through JNK, p38 and Nrf2 pathways.

The tubers of Apios americana Medikus possess high nutritional value and have been used as food in many countries for a long time. However, few researches have focused on the tuber polysaccharides. In the present study, a purified polysaccharide (ATP-1) was isolated with the average molecular weights of 12.16 kDa. ATP-1 significantly suppressed the release of nitric oxide (NO) and inflammatory cytokines from LPS-induced RAW 264.7 cells, as well as oxidative stress and mitochondrial dysfunction. Meanwhile, ATP-1 reduced oxidative damage via the NF-κB, MAPKs and Nrf2-Keap1 signaling pathways in RAW264.7 macrophages. Furthermore, autophagy was activated by HMGB1-Beclin1, Sirt1-FoxO1 and Akt-mTOR signaling pathways, leading to a relief of oxidative stress, mitochondrial dysfunction, inflammation and an expression enhancement of autophagy-related proteins, such as LC3, Beclin1, Atg4, Atg5, and Atg7. In summary, our results suggested that ATP-1 might help to activate the anti-inflammation system，resulting in prevention of LPS-induced damage in RAW264.7 cells.

Arsenic trioxide (As2O3, ATO), a FDA approved drug for hematologic malignancies, was proved of efficient growth inhibition of cancer cell in vitro or solid tumor in vivo. However, its effect on solid tumor in vivo was hampered by its poor pharmacokinetics and dose-limited toxicity. In this study, a polyacrylic acid capped pH-triggered mesoporous silica nanoparticles was conducted to improve the pharmacokinetics and enhance the antitumor effect of arsenic trioxide. The mesoporous silica nanoparticles loaded with arsenic trioxide was grafted with polyacrylic acid (PAA-ATO-MSN) as a pH-responsive biomaterial on the surface to achieve the release of drug in acidic microenvironment of tumor, instead of burst release action in circulation. The nanoparticles were characterized with uniform grain size (particle sizes of 158.6 ± 1.3 nm and pore sizes of 3.71 nm, respectively), historically comparable drug loading efficiency (11.42 ± 1.75%), pH-responsive and strengthened sustained release features. The cell toxicity of amino groups modified mesoporous silica nanoparticles (NH2-MSN) was significantly reduced by capping of polyacrylic acid. In pharmacokinetic studies, the half time (t1/2β) was prolonged by 1.3 times, and the area under curve) was increased by 2.6 times in PAA-ATO-MSN group compared with free arsenic trioxide group. Subsequently, the antitumor efficacy in vitro (SMMC-7721 cell line) and in vivo (H22 xenografts) was remarkably enhanced indicated that PAA-ATO-MSN improved the antitumor effect of the drug. These results suggest that the polyacrylic acid capped mesoporous silica nanoparticles (PAA-MSN) will be a promising nanocarrier for improving pharmacokinetic features and enhancing the anti-tumor efficacy of arsenic trioxide.

The main flavonoid components of Radix Tetrastigma (RTF) were extracted and characterized by high performance liquid chromatography. In vitro, RTF suppressed the viability of A549 cells, and inhibited the invasion and migration of A549 by damaging the lamellipodium and the structure of F-actin. In vivo, compared to the model group, RTF inhibited the growth of tumor volumes in nude mice, and decreased the weight of tumor. To uncover the inner mechanism, the proliferation-related proteins: PCNA, Ki67 and the apoptosis-related proteins: caspase-3, caspase-9, Bax and Bcl-2 were examined by immunohistochemical and western blot analysis. Compared to the model group, the production levels of PCNA, Ki67 and Bcl-2 were significantly down-regulated by RTF, and the expression levels of caspase-3, caspase-9 and Bax were markedly up-regulated. Comprehensively, RTF could suppress the proliferation of A549 and promote the apoptosis of A549, suggesting RTF as a potential resource to fight against non-small cell lung cancer (NSCLC).

Non-toxigenic Bacteroides fragilis is regarded as a potential candidate for probiotic owing to its various advantages. We previously isolated a new strain of B. fragilis (ZY-312) and verified its biosafety and capability of inhibiting the growth of pathogens in vivo. However, the colonization of ZY-312 in gastrointestinal (GI) tract remains to be determined. To track the colonization of ZY-312, mice were gavaged with ZY-312 labeled by means of metabolic oligosaccharide engineering and bioorthogonal click chemistry or given AF647-dibenzocyclooctyne (DIBO) directly. Then the fluorescence was detected in GI tract, spleen and kidneys. Results showed that ZY-312 could be labeled by metabolic oligosaccharide engineering, and the optimal incubation time with AF647-DIBO was 5 h in vitro. Following oral gavage with AF647-DIBO labeled ZY-312 or AF647-DIBO alone, mice were subjected to in vivo imaging and the fluorescence intensity was similar in both groups 3 h, 6 h, and 12 h post the gavage. The fluorescence of AF647-DIBO group disappeared 24 h post gavage which was probably due to the excretion via GI tract. While the fluorescence of AF647-DIBO labeled ZY-312 retained in the cecum for as long as 48 h. Immunofluorescence assay further confirmed that labeled ZY-312 transiently colonized not only in cecum but also in stomach, ileum and colon of mice 48 h post-gavage and that no massive accumulation of ZY-312 was detected in other organs such as kidneys and spleen. In conclusion, ZY-312 could transiently colonize in GI tract, mainly in cecum, for at least 48 h, and it hardly disseminate to other organs, which shed new light on the future development of B. fragilis as a probiotic product.

Thermosensitive poly(N-isopropylacrylamide) (PNIPAM)-based substrates have presented great promise in cell sheet engineering. However, non-functionalized PNIPAM cannot be well applied for cell cultivation, due to the low cell adhesion. Herein, to enhance PNIPAM-based substrates and to promote cell proliferation and detachment, a polyhedral oligomeric silsesquioxane (POSS) nanoscale inorganic enhanced agent has been introduced into PNIPAM matrices to construct POSS-containing hybrid hydrogels. The hydrogels were facilely prepared using POSS as a cross-linker via one-pot crosslinking reaction under UV irradiation. The swelling behavior, thermal stability and the mechanical properties of POSS–PNIPAM hybrid hydrogels have been evaluated and they are all dependent on the content of POSS. The in vitro experiment confirms that human amniotic mesenchymal stem cells (hAMSCs) exhibit clearly enhanced adhesion and proliferation on the substrates of POSS–PNIPAM hybrid hydrogels in comparison to the pure PNIPAM hydrogel without POSS. Based on the thermal-responsiveness of PNIPAM, the proliferated cells are easily released without damage from the surface of hybrid hydrogels. Therefore, POSS-enhanced PNIPAM hybrid hydrogels provide a unique approach for harvesting anchorage dependent stem cells.

Structure and structural changes in 3-tetradecyloxy-2-hydroxypropyl trimethyl ammonium bromide (R14HTAB)/H2O mixtures have been studied by steady and dynamic shear rheology. The results showed that the self-aggregate undergo two transitions in shape from spherical to rod-like micelles to viscoelastic wormlike micelles and to the hexagonal lytropic liquid crystal in the investigated concentration range. The transition of spherical micelles into rod-like micelles takes place above 300 mmol kg−1. The overlap threshold micelle concentration is about 500 mmol kg−1, and the η0 and R14HTAB concentrations give relationship of the power law, i.e. . The microstructure of the formed micelles has been further ascertained by FF-transmission electronic microscopy. The deviations from Cox–Merz rule for the complex dynamic viscosity and the shear viscosity at above the critical shear rate mainly come from the formation of hydrogen bond.

2,2-Dioxides of 1-R-1H-2,1-benzothiazin-4(3H)-ones easily undergo a three-component condensation with N-substituted isatins and malononitrile in the presence of triethylamine giving 6'-R-1-R1-2'-amino-2-oxo-1,2-dihydro-6'H-spiro[indole-3,4'-pyrano[3,2-c][2,1]benzothiazine]-3'-carbonitrile 5',5'-dioxides in good yields. The reaction with 1-unsubstituted 1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide follows an analogous route, but the products are triethylammonium salts of the corresponding spiro compounds.

Hydrolysis of 1-R-4-hydroxy-2,2-dioxo-1Н-2λ6,1-benzothiazine-3-carboxylate esters in HCl–AcOH–H2O mixture at 60°С was accompanied by decarboxylation and led to 1-R-4-oxo-3,4-dihydro-1H-2λ6,1-benzo-thiazine-2,2-diones. In the alkaline medium, regardless of the type of the substituent at position 1, analogous structural transformations occurred at first, but the thiazine ring was also destroyed along with the ester fragment when performing the reaction for a longer time.

An improved method has been proposed for the reaction of the methyl ester of 4-hydroxy-1-methyl-2,2-di-oxo-1H-2λ6,1-benzothiazine-3-carboxylic acid with hetarylamines to give 4-hydroxy-1-methyl-2,2-di-oxo-N-(pyridin-2-yl)-1H-2λ6,1-benzothiazine-3-carboxamides and analogs with the similar structure in good yield and purity. X-ray diffraction structural analysis has indicated that these products exist as internal salts. A mass spectral study of these compounds has shown that they have a characteristically enhanced tendency to extrude SO2. The pharmacological testing has revealed promising compounds with better analgesic properties than those of the known oxicam drugs.

In order to study the relation of Abscisic Acid (ABA) with other biochemistry factors during hardy kiwifruit softening process. The changing trend of ABA under the fruits storage conditions of 20 and 0°C was analyzed. A conclusion is drawn as below: During storage under 20°C, it shows the highest content of ABA in 4 days to 222.19 µg/L, which reaches the almost same content in 3 and 5 days. The value keeps inclining since 5 days and decline rate is lower in 7 and 8 days. The lowest value is reached to 20.88 µg/L in 10 days. During storage under 0°C, ABA content is at a relatively high level but shows the slow down trend. ABA content falls greatly from 9 to 11 days. After this period, ABA content still follows up-trend and declining then. The peak appears in 15 days to 90.49 µg/L, but it is lower than that in the first nine days. Moreover, peak during storage in environment under 0°C is lower than that during the storage in environment at normal temperature, accordingly delaying fruit softening. As the ABA content rises to the highest level, the fruit hardness drops drastically. When ABA content slightly changes, the hardness decreases gently. ABA content is featured that same changing trend of ethylene content, respiratory intensity, pectase content and amylase content. Moreover, ABA has the same peak appearance time as amylase but it is later than appearance of both pectase and ethylene, they basically match each other. The rule of peak appearance time is not obvious for ABA and amylase. Mutual inhibition exists between peak appearance time of ABA and respiratory intensity. Quick ABA rise is accompanied with slow amylase rise and vice versa.

NMR spectroscopy showed that treatment of 1-allyl-3-[(arylamino)methylene]quinoline-2,4-(1H,3H)-diones with an equivalent amount of dry bromine in anhydrous acetic acid leads to the formation of 4-aryliminomethyl-2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo[3,2-a]quinolinium bromides.

Alkylidenehydrazides have been synthesized by the reaction of 1-R-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid hydrazides with lower dialkyl ketones in order to reveal a structureantitubercular activity relationship. It was shown by 1 H NMR spectroscopy that hydrazones obtained from the unsymmetrical ketone – methyl ethyl ketone – exist primarily in the E-isomer form. It was found that the presence of two aliphatic substituents in the alkylidene fragment of the compounds investigated leads to a marked lowering of antimic obacterial properties. r

Bromination of 1-allyl-substituted 3-(arylaminomethylene)quinoline-2,4-(1H,3H)-diones with one equivalent of molecular bromine in glacial acetic acid and subsequent dilution of the reaction mixture with water is accompanied by halocyclization and hydrolysis to form 2-bromomethyl-5-oxo-1,2 dihydro-5H-oxazolo[3,2-a]quinoline-4-carbaldehyde.

Condensation of 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carbaldehydes, thioglycolic acid (or methyl thioglycolate), and anilines does not lead to the synthesis of the corresponding thiazolidinylquinolones because the Schiff bases so formed exist exclusively in a form inert to enamine thioglycolates. 1 H NMR spectroscopy showed that the main components of the isolated 3-arylaminomethylenequinoline-2,4-(1H,3H)-diones are E-isomers. The results of a study of the antitubercular properties of the compounds obtained are presented.

Two variants are discussed of the synthesis of 1-R-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid β-N-tosylhydrazides which undergo a McFayden-Stevens reaction to give 1-R-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carbaldehydes in high yields. It was shown that the thiosemicarbazones prepared from them exist in the solid state exclusively in the syn-form while in solution a hydrazone ↔ enhydrazine tautomerism is observed. The results of a study of the antitubercular activity of the synthesized compounds are reported.

Hydrolysis of the title benzothiazinecarboxylates (I) is accompanied by decarboxylation both in acidic and alkaline medium.