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SUMMARY: The successful interaction between pollen and stigma is a critical process for plant sexual reproduction, involving a series of intricate molecular and physiological events. After self‐compatible pollination, a significant reduction in reactive oxygen species (ROS) production has been observed in stigmas, which is essential for pollen grain rehydration and subsequent pollen tube growth. Several scavenging enzymes tightly regulate ROS homeostasis. However, the potential role of these ROS‐scavenging enzymes in the pollen‐stigma interaction in Brassica napus remains unclear. Here, we showed that the activity of ascorbate peroxidase (APX), an enzyme that plays a crucial role in the detoxification of hydrogen peroxide (H2O2), was modulated depending on the compatibility of pollination in B. napus. We then identified stigma‐expressed APX1s and generated pentuple mutants of APX1s using CRISPR/Cas9 technology. After compatible pollination, the BnaAPX1 pentuple mutants accumulated higher levels of H2O2 in the stigma, while the overexpression of BnaA09.APX1 resulted in lower levels of H2O2. Furthermore, the knockout of BnaAPX1 delayed the compatible response‐mediated pollen rehydration and germination, which was consistent with the effects of a specific APX inhibitor, ρ‐Aminophenol, on compatible pollination. In contrast, the overexpression of BnaA09.APX1 accelerated pollen rehydration and germination after both compatible and incompatible pollinations. However, delaying and promoting pollen rehydration and germination did not affect the seed set after compatible and incompatible pollination in APX1 pentuple mutants and overexpression lines, respectively. Our results demonstrate the fundamental role of BnaAPX1 in pollen rehydration and germination by regulating ROS homeostasis during the pollen‐stigma interaction in B. napus. Significance Statement: Our research found that self‐incompatibility in Brassica napus requires the accumulation of reactive oxygen species (ROS) levels in the stigma. We identified the importance of BnaAPX1 in regulating ROS homeostasis, which is critical for pollen rehydration and germination in B. napus. [ABSTRACT FROM AUTHOR]

Persistent human papillomavirus (HPV) infection is associated with multiple malignancies. Developing therapeutic vaccines to eliminate HPV‐infected and malignant cells holds significant value. In this study, we introduced a lipid nanoparticle encapsulated mRNA vaccine expressing tHA‐mE7‐mE6. Mutations were introduced into E6 and E7 of HPV to eliminate their tumourigenicity. A truncated influenza haemagglutinin protein (tHA), which binds to the CD209 receptor on the surface of dendritic cells (DCs), was fused with mE7‐mE6 in order to allow efficient uptake of antigen by antigen presenting cells. The tHA‐mE7‐mE6 (mRNA) showed higher therapeutic efficacy than mE7‐mE6 (mRNA) in an E6 and E7+ tumour model. The treatment resulted in complete tumour regression and prevented tumour formation. Strong CD8+ T‐cell immune response was induced, contributing to preventing and curing of E6 and E7+ tumour. Antigen‐specific CD8+ T were found in spleens, peripheral blood and in tumours. In addition, the tumour infiltration of DC and NK cells were increased post therapy. In conclusion, this study described a therapeutic mRNA vaccine inducing strong anti‐tumour immunity in peripheral and in tumour microenvironment, holding promising potential to treat HPV‐induced cancer and to prevent cancer recurrence. [ABSTRACT FROM AUTHOR]

Summary: Self‐incompatibility plays a vital role in angiosperms, by preventing inbreeding depression and maintaining genetic diversity within populations. Following polyploidization, many angiosperm species transition from self‐incompatibility to self‐compatibility.Here, we investigated the S‐locus in Brassicaceae and identified distinct origins for the sRNA loci, SMI and SMI2 (SCR Methylation Inducer 1 and 2), within the S‐locus. The SMI loci were found to be widespread in Cruciferae, whereas the SMI2 loci were exclusive to Brassica species.Additionally, we discovered four major S‐haplotypes (BnS‐1, BnS‐6, BnS‐7, and BnS‐1300) in rapeseed. Overexpression of BnSMI‐1 in self‐incompatible Brassica napus ('S‐70S1300S6') resulted in a significant increase in DNA methylation in the promoter regions of BnSCR‐6 and BnSCR‐1300, leading to self‐compatibility. Conversely, by overexpressing a point mutation of BnSmi‐1 in the 'S‐70S1300S6' line, we observed lower levels of DNA methylation in BnSCR‐6 and BnSCR‐1300 promoters. Furthermore, the overexpression of BnSMI2‐1300 in the 'SI‐326S7S6' line inhibited the expression of BnSCR‐7 through transcriptional repression of the Smi2 sRNA from the BnS‐1300 haplotype.Our study demonstrates that the self‐compatibility of rapeseed is determined by S‐locus sRNA‐mediated silencing of SCR after polyploidization, which helps to further breed self‐incompatible or self‐compatible rapeseed lines, thereby facilitating the utilization of heterosis. [ABSTRACT FROM AUTHOR]

To identify the process of tourism place making by using intangible cultural heritage (ICH) as the resource, this study conducts a qualitative meta‐analysis based on 23 European and 16 Chinese cases. The results conclude and replenish the main considerations in creating tourist destinations with ICH, including planner, ICH type, specific place making scope, purpose, design focus, types of placemaking, and sense of place. Findings reveal differentiated patterns and similar methods in the decision‐making process in the two regions. This article provides a new perspective on taking ICH as place making tool and sheds light on ICH resource development. [ABSTRACT FROM AUTHOR]

Multidrug resistance remains a great challenge for cancer chemotherapy. Herein, a biomimetic drug delivery system based on lemon‐derived extracellular vesicles (EVs) nanodrugs (marked with heparin‐cRGD‐EVs‐doxorubicin (HRED)) is demonstrated, achieving highly efficient overcoming cancer multidrug resistance. The HRED is fabricated by modifying functional heparin‐cRGD (HR) onto the surface of EVs and then by loading with doxorubicin (DOX). The obtained HRED enable to effectively enter DOX‐resistant cancer cells by caveolin‐mediated endocytosis (main), macropinocytosis (secondary), and clathrin‐mediated endocytosis (last), exhibiting excellent cellular uptake capacity. The diversified endocytosis capacity of HRED can efficiently dissipate intracellular energy and meanwhile trigger downstream production reduction of adenosine triphosphate (ATP), leading to a significant reduction of drug efflux. Consequently, they show excellent anti‐proliferation capacities to DOX‐resistant ovarian cancer, ensuring the efficiently overcoming ovarian cancer multidrug resistance in vivo. The authors believe this strategy provides a new strategy by endocytosis triggered‐energy dissipation and ATP production reduction to design drug delivery system for overcoming cancer multidrug resistance. [ABSTRACT FROM AUTHOR]

The development of alcoholic fatty liver is associated with reduced adipocyte-derived adiponectin levels, decreased hepatic adiponectin receptors, and deranged hepatic adiponectin signaling in animals. Peroxisomal proliferator-activated receptor-[gamma] (PPAR-[gamma]) plays a key role in the regulation of adiponectin in adipose tissue. The aim of the present study was to test the ability of rosiglitazone, a known PPAR-[gamma] agonist, to reverse the inhibitory effects of ethanol on adiponectin expression and its hepatic signaling, and to attenuate alcoholic liver steatosis in mice. Mice were fed modified Lieber-DeCarli ethanol-containing liquid diets for 4 wk or pair-fed control diets. Four groups of mice were given a dose of either 3 or l0 mg x kg body [w.sup.-1] x [day.sup.-1] of rosiglitazone with or without ethanol in their diets for the last 2 wk of the feeding study. Coadministration of rosiglitazone and ethanol increased the expression and circulating levels of adiponectin and enhanced the expression of hepatic adiponectin receptors (AdipoRs) in mice. These increases correlated closely with the activation of a hepatic sirtuin 1 (SIRT1)-AMP-activated kinase (AMPK) signaling system. In concordance with stimulated SIRT1-AMPK signaling, rosiglitazone administration enhanced expression of fatty acid oxidation enzymes, normalized lipin 1 expression, and blocked elevated expression of genes encoding lipogenic enzymes which, in turn, led to increased fatty acid oxidation, reduced lipogenesis, and alleviation of steatosis in the livers of ethanol-fed mice. Enhanced hepatic adiponectin-SIRT1-AMPK signaling contributes, at least in part, to the protective action of rosiglitazone against alcoholic fatty liver in mice. lipid metabolism; signal transduction; transcriptional regulators; acetylation doi:10.1152/ajpgi.00456.2009.

Dysregulation of proinflammatory cytokines such as tumor necrosis factor-[alpha] (TNF-[alpha]) has been implicated in the pathogenesis of alcoholic liver injury. Sirtuin 1 (SIRT1) is an [NAD.sup.+]-dependent class III protein deacetylase that is known to be involved in regulating production of proinflammatory cytokines including TNF-[alpha]. In the present study, we examined the role of SIRT1 signaling in TNF-[alpha] generation stimulated by either lipopolysaccharide (LPS), acetaldehyde (AcH), or acetate (two major metabolites of ethanol) in two cultured macrophage cell lines. In both rat Kupffer cell line 1 (RKC1) and murine RAW 264.7 macrophages, treatment with either LPS, AcH, or acetate caused significant decreases in SIRT1 transcription, translation, and activation, which essentially demonstrated an inverse relationship with TNF-[alpha] levels. LPS, AcH, and acetate each provoked the release of TNF-[alpha] from RKC1 cells, whereas coincubation with resveratrol (a potent SIRT1 agonist) inhibited this effect. Conversely, addition of sirtinol (a known SIRT1 inhibitor) or knocking down SIRT1 by the small silencing SIRT1 plasmid (SIRT1shRNA) augmented TNF-[alpha] release, suggesting that impairment of SIRT1 may contribute to TNF-[alpha] secretion. Further mechanistic studies revealed that inhibition of SIRT1 by LPS, AcH, or acetate was associated with a marked increase in the acetylation of the RelA/p65 subunit of nuclear transcription factor (NF-[kappa]B) and promotion of NF-[kappa]B transcriptional activity. Taken together, our findings suggest that SIRT1-NF-[kappa]B signaling is involved in regulating LPS- and metabolites-of-ethanol-mediated TNF-[alpha] production in rat Kupffer cells and in murine macrophages. Our study provides new insights into understanding the molecular mechanisms underlying the development of alcoholic steatohepatitis. inflammation; adiponectin; signal transduction

Alcoholic fatty liver is associated with inhibition of sirtuin 1 (SIRT1) and AMP-activated kinase (AMPK), two critical signaling molecules regulating the pathways of hepatic lipid metabolism in animals. Resveratrol, a dietary polyphenol, has been identified as a potent activator for both SIRT1 and AMPK. In the present study, we have carried out in vivo animal experiments that test the ability of resveratrol to reverse the inhibitory effects of chronic ethanol feeding on hepatic SIRT1-AMPK signaling system and to prevent the development of alcoholic liver steatosis. Resveratrol treatment increased SIRT1 expression levels and stimulated AMPK activity in livers of ethanol-fed mice. The resveratrol-mediated increase in activities of SIRT1 and AMPK was associated with suppression of sterol regulatory element binding protein 1 (SREBP-) and activation of peroxisome proliferator-activated receptor [gamma] coactivator a (PGC-1[alpha]). In parallel, in ethanol-fed mice, resveratrol administration markedly increased circulating adiponectin levels and enhanced mRNA expression of hepatic adiponectin receptors (AdipoR1/R2). In conclusion, resveratrol treatment led to reduced lipid synthesis and increased rates of fatty acid oxidation and prevented alcoholic liver steatosis. The protective action of resveratrol is in whole or in part mediated through the upregulation of a SIRT1-AMPK signaling system in the livers of ethanol-fed mice. Our study suggests that resveratrol may serve as a promising agent for preventing or treating human alcoholic fatty liver disease. alcoholic liver steatosis; lipid metabolism; sirtuin 1; AMP-activated kinase; acetylation; sterol regulatory element-binding protein 1c; peroxisome proliferator-activated receptor [gamma] coactivator [alpha]

Chronic ethanol feeding causes liver steatosis in animal models by upregulating the sterol regulatory element-binding protein 1 (SREBP-1), which subsequently increases the synthesis of hepatic lipid. SREBP-1 activity is regulated by reversible acetylation at specific lysine residues. The present study tests the hypothesis that activation of SREBP-1 by ethanol may be mediated by mammalian sirtuin 1 (SIRT1), a [NAD.sup.+]-dependent class III protein deacetylase. The effects of ethanol on SIRT1 were determined in cultured rat hepatoma cells and in the livers of ethanol-fed mice. In rat H4IIEC3 cells, we observed that ethanol exposure induced SREBP-1c lysine acetylation and SREBP-1c transcriptional activity. The effect of ethanol was abolished by expression of wild-type SIRT1 or by treatment with resveratrol, a known potent SIRT1 agonist. Conversely, knocking down SIRT1 by the small silencing SIRT1 plasmid SIRT1shRNA or expression of a SIRT1 mutant, SIRTl(H363Y), did not negate the ethanol effect. These findings suggest that the effect of ethanol on SREBP-1 is mediated, at least in part, through SIRT1 inhibition. Consistent with the in vitro findings, chronic ethanol feeding substantially downregulated hepatic SIRT1 in mice. Inhibition of hepatic SIRT 1 activity was associated with an increase in the acetylated active nuclear form of SREBP-Ic in the livers of ethanol-fed mice. Our results indicate an essential role for SIRT1 in mediating the effects of ethanol on SREBP-1 and hepatic lipid metabolism, as well as the development of alcoholic fatty liver. Hence, SIRT1 may represent a novel therapeutic target for treatment of human alcoholic fatty liver disease. alcoholic liver steatosis; lipid metabolism; acetylation; sterol regulatory element-binding protein-1c; peroxisome proliferator-activated receptor-[gamma] coactivator-1 [alpha]

This study was undertaken to elucidate the mechanism underling the protective effect of a high saturated fat (HSF) diet against the development of alcoholic fatty liver in mice. We tested the effects of a HSF diet on the ethanol-mediated increase in hepatic sterol regulatory element binding protein 1 (SREBP-1) activity. Thirty-two male mice were divided into 4 groups and fed liquid diets consisting of either a high polyunsaturated fat (40% of energy from corn oil) or a HSF (40% of energy from cocoa butter) diet with or without ethanol for 4 wk. In the ethanol-containing diets, ethanol was substituted for an equivalent amount of carbohydrate to provide 27.5% of the total energy. Control mice were pair-fed the same volume of liquid diets as the ethanol-fed mice. The HSF diet suppressed the increase in mature SREBP-1 protein and prevented increased mRNA of the SREBP-l-regulated lipogenic enzymes in the ethanol-fed mice (P < 0.05). Sirtuins 1 (SIRT1), a [NAD.sup.+]-dependent class III histone deacetylase, was upregulated by ethanol administration in mice fed the HSF diet (P < 0.05). The HSF diet blocked histone H3 at lysine 9 (lys9) hyperacetylation and attenuated association of acetylated histone H3-Lys9 with the promoters of mitochondrial glycerol-3-phosphate acyltransferase and stearoyl-CoA desaturase 1 in the livers of the ethanol-fed mice. These results suggest that the protective effects of HSF diet against the development of alcoholic liver steatosis may occur via regulation of the hepatic SIRT1-SREBP-l-histone H3 axis, suppressing the expression of genes encoding lipogenic enzymes and slowing the synthesis of hepatic fatty acids.

Objective We aimed to identify key susceptibility gene targets in multiple datasets generated from postmortem brains and blood of Parkinson's disease (PD) patients and healthy controls (HC). Methods We performed a multitiered analysis to integrate the gene expression data using multiple-gene chips from 244 human postmortem tissues. We identified hub node genes in the highly PD-related consensus module by constructing protein–protein interaction (PPI) networks. Next, we validated the top four interacting genes in 238 subjects (90 sporadic PD, 125 HC and 23 Parkinson's Plus Syndrome (PPS)). Utilizing multinomial logistic regression analysis (MLRA) and receiver operating characteristic (ROC), we analyzed the risk factors and diagnostic power for discriminating PD from HC and PPS. Results We identified 1333 genes that were significantly different between PD and HCs based on seven microarray datasets. The identified MEturquoise module is related to synaptic vesicle trafficking (SVT) dysfunction in PD (P  < 0.05), and PPI analysis revealed that SVT genes PPP2CA, SYNJ1, NSF and PPP3CB were the top four hub node genes in MEturquoise (P  < 0.001). The levels of these four genes in PD postmortem brains were lower than those in HC brains. We found lower blood levels of PPP2CA, SYNJ1 and NSF in PD compared with HC, and lower SYNJ1 in PD compared with PPS (P  < 0.05). SYNJ1, negatively correlated to PD severity, displayed an excellent power to discriminating PD from HC and PPS. Conclusions This study highlights that SVT genes, especially SYNJ1, may be promising markers in discriminating PD from HCs and PPS. [ABSTRACT FROM AUTHOR]

Abstract Background Enzymatic biodiesel production by transesterification in solvent media has been investigated intensively, but glycerol, as a by-product, could block the immobilized enzyme and excess n-hexane, as a solution aid, would reduce the productivity of the enzyme. Esterification, a solvent-free and no-glycerol-release system for biodiesel production, has been developed, and two-step catalysis of soybean oil, hydrolysis followed by esterification, with Yarrowia lipolytica lipase is reported in this paper. Results First, soybean oil was hydrolyzed at 40°C by 100 U of lipase broth per 1 g of oil with approximately 30% to 60% (vol/vol) water. The free fatty acid (FFA) distilled from this hydrolysis mixture was used for the esterification of FFA to fatty acid ethyl ester by immobilized lipase. A mixture of 2.82 g of FFA and equimolar ethanol (addition in three steps) were shaken at 30°C with 18 U of lipase per 1 gram of FFA. The degree of esterification reached 85% after 3 hours. The lipase membranes were taken out, dehydrated and subjected to fresh esterification so that over 82% of esterification was maintained, even though the esterification was repeated every 3 hours for 25 batches. Conclusion The two-step enzymatic process without glycerol released and solvent-free demonstrated higher efficiency and safety than enzymatic transesterification, which seems very promising for lipase-catalyzed, large-scale production of biodiesel, especially from high acid value waste oil.

Thymoquinone, a natural occurring quinone and the main bioactive component of plant Nigella sativa, undergoes intracellular redox cycling and re-oxidizes NADH to NAD+. TQ administration (20 mg/kg/bw/day) to the Diet-Induced Obesity (DIO) mice reduced their diabetic phenotype by decreasing fasting blood glucose and fasting insulin levels, and improved glucose tolerance and insulin sensitivity as evaluated by oral glucose and insulin tolerance tests (OGTT and ITT). Furthermore, TQ decreased serum cholesterol levels and liver triglycerides, increased protein expression of phosphorylated Akt, decreased serum levels of inflammatory markers resistin and MCP-1, and decreased NADH/NAD+ ratio. These changes were paralleled by an increase in phosphorylated SIRT-1 and AMPKα in liver and phosphorylated SIRT-1 in skeletal muscle. TQ also increased insulin sensitivity in insulin-resistant HepG2 cells via a SIRT-1-dependent mechanism. These findings are consistent with the TQ-dependent re-oxidation of NADH to NAD+, which stimulates glucose and fatty acid oxidation and activation of SIRT-1-dependent pathways. Taken together, these results demonstrate that TQ ameliorates the diabetic phenotype in the DIO mouse model of type 2 diabetes. [ABSTRACT FROM AUTHOR]

Objective: We perform this meta-analysis was to evaluate the efficacy of neoadjuvant chemotherapy followed by radiation in the treatment of locally advanced nasopharyngeal carcinoma.Materials and Methods: We searched the database of Medline and Wanfang to screen and included the prospective, randomized controlled trials of neoadjuvant chemotherapy plus radiation versus radiotherapy in the treatment of locally advanced nasopharyngeal carcinoma. The pooled 5-year overall survival, 5 years disease free survival, recurrence rate, and metastasis rate were calculated by Stata version 11.0 statistical software.Results: Five prospective clinical studies were included in this meta-analysis. The total number of cases included in this study was 1277. The pooled 5 years overall survival and 5 years disease free survival were not statistical different between the neoadjuvant chemotherapy plus radiation group and radiotherapy group, respectively (P > 0.05). But the recurrence rate (odds ratio [OR] = 0.65, P < 0.05) and metastasis rate (OR = 0.61, P < 0.05) were significantly lower in the neoadjuvant chemotherapy plus radiation group compared to radiotherapy group.Conclusion: Neoadjuvant chemotherapy followed by radiation can decrease the risk of recurrence and metastasis but not improve the 5 years overall survival and 5 years disease free survival compared to radiotherapy alone in the patients with locally advanced nasopharyngeal carcinoma. [ABSTRACT FROM AUTHOR]

Background & Aims: Sirtuin (SIRT1) is a nicotinamide adenine dinucleotide−dependent protein deacetylase that regulates hepatic lipid metabolism by modifying histones and transcription factors. Ethanol exposure disrupts SIRT1 activity and contributes to alcoholic liver disease in rodents, but the exact pathogenic mechanism is not clear. We compared mice with liver-specific deletion of Sirt1 (Sirt1LKO) mice with their LOX littermates (controls). Methods: We induced alcoholic liver injury in male Sirt1LKO and control mice, placing them on Lieber-DeCarli ethanol-containing diets for 10 days and then administering a single dose of ethanol (5 g/kg body weight) via gavage. Liver and serum samples were collected. We also measured messenger RNA levels of SIRT1, SFRS10, and lipin-1β and lipin-1α in liver samples from patients with alcoholic hepatitis and individuals without alcoholic hepatitis (controls). Results: On the ethanol-containing diet, livers of Sirt1LKO mice accumulated larger amounts of hepatic lipid and expressed higher levels of inflammatory cytokines than control mice; serum of Sirt1LKO mice had increased levels of alanine aminotransferase and aspartate aminotransferase. Hepatic deletion of SIRT1 exacerbated ethanol-mediated defects in lipid metabolism, mainly by altering the function of lipin-1, a transcriptional regulator of lipid metabolism. In cultured mouse AML-12 hepatocytes, transgenic expression of SIRT1 prevented fat accumulation in response to ethanol exposure, largely by reversing the aberrations in lipin-1 signaling induced by ethanol. Liver samples from patients with alcoholic hepatitis had reduced levels of SIRT1 and a higher ratio of Lpin1β/α messenger RNAs than controls. Conclusions: In mice, hepatic deletion of Sirt1 promotes steatosis, inflammation, and fibrosis in response to ethanol challenge. Ethanol-mediated impairment of hepatic SIRT1 signaling via lipin-1 contributes to development of alcoholic steatosis and inflammation. Reagents designed to increase SIRT1 regulation of lipin-1 can be developed to treat patients with alcoholic fatty liver disease. [Copyright &y& Elsevier]

Short branched-chain acyl-CoAs are important building blocks for a wide variety of pharmaceutically valuable natural products. Escherichia coli has been used as a heterologous host for the production of a variety of natural compounds for many years. In the current study, we engineered synthesis of isobutyryl-CoA and isovaleryl-CoA from glucose in E. coli by integration of the branched-chain α-keto acid dehydrogenase complex from Streptomyces avermitilis. In the presence of the chloramphenicol acetyltransferase ( cat) gene, chloramphenicol was converted to both chloramphenicol-3-isobutyrate and chloramphenicol-3-isovalerate by the recombinant E. coli strains, which suggested successful synthesis of isobutyryl-CoA and isovaleryl-CoA. Furthermore, we improved the α-keto acid precursor supply by overexpressing the alsS gene from Bacillus subtilis and the ilvC and ilvD genes from E. coli and thus enhanced the synthesis of short branched-chain acyl-CoAs. By feeding 25 mg/L chloramphenicol, 2.96 ± 0.06 mg/L chloramphenicol-3-isobutyrate and 3.94 ± 0.06 mg/L chloramphenicol-3-isovalerate were generated by the engineered E. coli strain, which indicated efficient biosynthesis of short branched-chain acyl-CoAs. HPLC analysis showed that the most efficient E. coli strain produced 80.77 ± 3.83 nmol/g wet weight isovaleryl-CoA. To our knowledge, this is the first report of production of short branched-chain acyl-CoAs in E. coli and opens a way to biosynthesize various valuable natural compounds based on these special building blocks from renewable carbon sources. [ABSTRACT FROM AUTHOR]

Most flowering plants have evolved a self-incompatibility (SI) system to maintain genetic diversity by preventing self-pollination. The Brassica species possesses sporophytic self-incompatibility (SSI), which is controlled by the pollen- and stigma-determinant factors SP11/SCR and SRK. However, the mysterious molecular mechanism of SI remains largely unknown. Here, a new class II S haplotype, named BrS-325, was identified in a pak choi line '325', which was responsible for the completely self-compatible phenotype. To obtain the entire S locus sequences, a complete pak choi genome was gained through Nanopore sequencing and de novo assembly, which provided a good reference genome for breeding and molecular research in B. rapa. S locus comparative analysis showed that the closest relatives to BrS-325 was BrS-60, and high sequence polymorphism existed in the S locus. Meanwhile, two duplicated SRKs (BrSRK-325a and BrSRK-325b) were distributed in the BrS-325 locus with opposite transcription directions. BrSRK-325b and BrSCR-325 were expressed normally at the transcriptional level. The multiple sequence alignment of SCRs and SRKs in class II S haplotypes showed that a number of amino acid variations were present in the contact regions (CR II and CR III) of BrSCR-325 and the hypervariable regions (HV I and HV II) of BrSRK-325s, which may influence the binding and interaction between the ligand and the receptor. Thus, these results suggested that amino acid variations in contact sites may lead to the SI destruction of a new class II S haplotype BrS-325 in B. rapa. The complete SC phenotype of '325' showed the potential for practical breeding application value in B. rapa. [ABSTRACT FROM AUTHOR]

Synthesis of two isomeric tetrasaccharides, β-D-Glup-(1→2)-α-L-Rhap-(1→3)-α-L- Rhap-(1→2)-α-L-Rhap (I) and β-D-Glup-(1→3)-α-L-Rhap-(1→3)-α-L-Rhap-(1→3)-α-L-Rhap (II), the repeating units from the lipopolysaccharides of the nitrogen-fixing bacterium Azospirillum brasilense S17 and Azospirillum lipoferum SR65, was achieved via assembly of the building blocks 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl trichloroacetimidate (2), p-methoxyphenyl 3,4-di-O-benzoyl-α-L-rhamnopyranoside (3), 3-O-allyloxycarbonyl-2,4-di-O-benzoyl-α-L-rhamnopyranosyl trichloroacetimidate (6), 2,3,4,6-tetra-O-benzoyl-β-D-glucopyranosyl trichloroacetimidate (8), and p-methoxy phenyl 2,4-di-O-benzoyl-α-L-rhamnopyranoside (14). Condensation of 3 with 6 or 8 provided the disaccharides 9 or 11, respectively. Deallyloxycarbonylation of 11 gave the disaccharide aceptor 12, while removal of the p-methoxyphenyl group in 9 followed by trichloroacetimidation of the anomeric hydroxyl group afforded the disaccharide donor 10. Meanwhile, disaccharide donor 16 and acceptor 18 were prepared from 6, 8, and 14 similarly. Finally, condensation of 10 with 12 or 16 with 18, followed by deprotection, gave the target tetrasaccharides I or II, respectively. [ABSTRACT FROM AUTHOR]

Four novel 5-acyloxyimino-5-deoxyavermectin B1 compounds have been synthesized from avermectin B1 by selective oxidization of the hydroxy group at C-5, followed by oximation and convenient esterification. Their structures were confirmed by IR, 1H NMR, 13C NMR and MS. Insecticidal activities of the intermediate oxime and the four new acyl derivatives were evaluated against Helicoverpa armigera, Spodoptera exigua and Musca domestica. [ABSTRACT FROM AUTHOR]

Brassicaceae species employ both self-compatibility and self-incompatibility systems to regulate post-pollination events. Arabidopsis halleri is strictly self-incompatible, while the closely related Arabidopsis thaliana has transitioned to self-compatibility with the loss of functional S-locus genes during evolution. The downstream signaling protein, ARC1, is also required for the self-incompatibility response in some Arabidopsis and Brassica species, and its gene is deleted in the A. thaliana genome. In this study, we attempted to reconstitute the SCR-SRK-ARC1 signaling pathway to restore self-incompatibility in A. thaliana using genes from A. halleri and B. napus, respectively. Several of the transgenic A. thaliana lines expressing the A. halleriSCR13-SRK13-ARC1 transgenes displayed self-incompatibility, while all the transgenic A. thaliana lines expressing the B. napusSCR1-SRK1-ARC1 transgenes failed to show any self-pollen rejection. Furthermore, our results showed that the intensity of the self-incompatibility response in transgenic A. thaliana plants was not associated with the expression levels of the transgenes. Thus, this suggests that there are differences between the Arabidopsis and Brassica self-incompatibility signaling pathways, which perhaps points to the existence of other factors downstream of B. napusSRK that are absent in Arabidopsis species. [ABSTRACT FROM AUTHOR]

Background: The results of the esophageal body motility differences between liquid and solid swallows from high‐resolution manometry (HRM) studies are not consistent. The information of the frequency of ineffective liquid and solid bolus swallows in healthy individuals during HRM procedure is limited. The normative values of the HRM parameters of both liquid and solid swallows for Chinese population are lacking. Methods: The esophageal HRM data of 101 healthy volunteers from multicenters in China were analyzed. The values of the HRM parameters were summarized and compared between liquid and solid swallows. The frequencies of ineffective liquid and solid swallows were summarized. Results: Esophagus contracted stronger and slower in solid bolus swallows than water swallows with HREM. Ineffective water swallow (DCI < 450 mm Hg.s.cm) and ineffective bread swallow (DCI < 800 mm Hg.s.cm) were frequently seen in asymptomatic individuals. The adding of bread swallows to the HREM procedure might cause diagnostic change in about 15.8% (16/101) of the asymptomatic individuals. Conclusions: The vigor and velocity of the esophageal peristalsis between liquid and solid bolus swallows are different. Ineffective water and solid bolus swallows are not rare. Adding solid bolus swallows brings diagnostic change, and it may be needed routinely for the HRM procedure. [ABSTRACT FROM AUTHOR]