Prevalence of the virulence genes and their correlation with carbapenem resistance amongst the Pseudomonas aeruginosa strains isolated from a tertiary hospital in China.

Pseudomonas aeruginosa is one of the top-listed pathogens in nosocomial infection. It is notorious for its complicated virulence system and rapid adaptability to drugs or antimicrobials. In this study, we aimed to evaluate the prevalence of sixteen virulence genes in four groups including type III secretion system, biofilm formation, extracellular toxin biosynthesis and enzymes amongst 209 clinical Pseudomonas aeruginosa strains. We investigated the different distribution patterns of virulence genotypes based on carbapenem-resistant phenotype or the carriage of carbapenemase genes. The detection rate of each virulence gene varied greatly. phzM and plcN were detected in all collected strains, while pilB and exoU were only carried by a small portion of isolates (6.7% and 16.3%). Additionally, the number of genotypes observed in each group of examined virulence genes ranged from 4 to 8. Only the distribution of genotypes of type III secretion system showed statistical difference between carbapenem-mediated or carbapenem-resistant and carbapenem-sensitive strains. The virulence genotype of Pseudomonas aeruginosa was possibly interrelated to its resistance mechanism. Further research suggested that one particular TTSS genotype exhibited higher ratio in carbapenemase-producing strains and exoS was less frequently detected in CRPA strains carrying carbapenemase gene. Generally, the significant genetic diversity of virulence genes amongst Pseudomonas aeruginosa strains was highlighted in this study. Specific TTSS genotypes were associated with carbapenem-resistance. In particular, certain incompatibility might exist between exoS and carbapenemase genes, which provided valuable information for further understanding the relationship between carbapenem resistance and virulence.

Inverse Mixed-Mode Chromatography for the Evaluation of Multivalency and Cooperativity of Host-Guest Complexation in Porous Materials.

A new separation-based analytical method was developed to evaluate the multivalency and cooperativity of supramolecular host-guest complexation in porous materials. The method is based on inverse mixed-mode chromatography in which a porous material with a multivalent functional group is packed into a column and bound with a complementary guest molecule to form a multivalent complex. The bound guest molecules are eluted in the mobile phase and detected by appropriate methods such as UV absorption. The retention factor of the guest molecule is determined and broken down into the contributions of noncovalent interactions between binding sites (e.g., hydrophobic and ionic components), thereby calculating the effective molarity and cooperativity factor of the complexation. Two model systems denoted as RP/SCX and RP/SAX were analyzed by the established method. On average, the RP/SCX system has an effective molarity (EM) of 0.14 M and a cooperativity factor (ß) of 0.86, while the RP/SAX system has an EM value of 0.18 M and a ß value of 2.3. Interestingly, experiments have shown that these values do not change with changes in the intrinsic binding strength of the constituent sites. In summary, the developed method allows for quantitative assessment of multivalency and cooperativity effects in porous materials, providing a valuable complement to the analytical toolbox for supramolecular chemists and materials scientists.

Age at Menarche and Incidence of Diabetes: A Prospective Study of 300,000 Women in China.

Previous studies of predominantly Western populations have reported inconsistent associations between age at menarche and risk of diabetes. We examined this relationship among Chinese women, who generally experience menarche at a later age than Western women. In 2004-2008, China Kadoorie Biobank recruited 302,632 women aged 30-79 years from 10 areas across China, and recorded 5,391 incident cases of diabetes during 7 years of follow-up among 270,345 women without baseline diabetes, cardiovascular disease or cancer. Cox regression models yielded adjusted hazard ratios for incident diabetes associated with age at menarche. Overall, the mean age at menarche was 15.4 years, and decreased across successive generations. Age at menarche was linearly and inversely associated with incident diabetes, with adjusted hazard ratio of 0.96 (95% confidence interval (CI): 0.94, 0.97) per year delay. Hazard ratios were greater in younger generations (for women born in the 1960s-1970s, hazard ratio (HR) = 0.93, 95% CI: 0.90, 0.97; for women born in the 1950s, HR = 0.95, 95% CI: 0.93, 0.98; and for women born in the 1920s-1940s, HR = 0.97, 95% CI: 0.95, 0.99). Further adjustment for adulthood body mass index significantly attenuated the association (HR = 0.99, 95% CI: 0.97, 1.00), especially among those born before 1950 (HR = 1.00, 95% CI: 0.97, 1.02). Much of the inverse association between age at menarche and incident diabetes was mediated through increased adiposity associated with early menarche, especially in older generations.

Proteome profiling reveals tissue-specific protein expression in male and female accessory glands of the silkworm, Bombyx mori.

Male accessory gland (MAG) and female accessory gland (FAG) of the reproductive system are, respectively, responsible for producing seminal proteins and adhesive proteins during copulation and ovulation. Seminal proteins are ejaculated to female along with sperms, whereas adhesive proteins are excreted along with eggs. Proteins from the male and female reproductive organs are usually indicative of rapid adaptive evolution. Understanding the reproductive isolation and species divergence requires identifying reproduction-related proteins from many different species. Here, we present our proteomic analyses of male and female accessory glands of the silkworm, Bombyx mori. Using LC/MS-MS, we identified 2133 MAG proteins and 1872 FAG proteins. In total, 652 proteins were significant more abundant in the MAG than in the FAG, including growth factors, odorant-binding proteins, enzymes, and proteins of unknown function. Growth factors and odorant-binding proteins are potential signaling molecules, whereas most of proteins of unknown function were found to be Lepidoptera-specific proteins with high evolutionary rates. Microarray experiments and semi-quantitative RT-PCR validated that MAG-specific proteins were expressed exclusively in male moths. Totally, 192 proteins were considered as FAG-specific proteins, including protease inhibitors, enzymes, and other proteins. Protease inhibitors were found to be the most abundant FAG-specific proteins, which may protect eggs from infection by inhibiting pathogen-derived proteases. These results provide comprehensive insights into copulation and oviposition. Moreover, the newly identified Lepidoptera-specific MAG proteins provide useful data for future research on the evolution of reproductive proteins in insects.

Optimized hydrolysis and analysis of Radix Asparagi polysaccharide monosaccharide composition by capillary zone electrophoresis.

Using orthogonal design, optimized conditions for the hydrolysis of the polysaccharide from Radix Asparagi were determined, as well as its monosaccharide composition. Optimized hydrolysis conditions were a temperature of 100°C in 1.5 M sulfuric acid solution for 5 h. The resulting monosaccharides were derivatized with 1-phenyl-3-methyl-5-pyrazolone, then separated by capillary zone electrophoresis in 40 mM sodium tetraborate buffer (pH 10.1), and detected by ultraviolet absorption at 245 nm. Results indicate that the polysaccharide from Radix Asparagi is composed of xylose, arabinose, glucose, rhamnose, mannose, galactose, glucuronic acid, and galacturonic acid, which differs from published findings. Moreover, xylose, glucuronic acid, and galacturonic acid have not been previously reported in Radix Asparagi polysaccharide. This method is simple, fast, and yields a highly efficient separation. As well, these findings can be applied to quality control of Radix Asparagi and for in-depth study of the biological activity of Radix Asparagi polysaccharide.

Transcriptome analysis reveals novel genes potentially involved in photoperiodic tuberization in potato.

Potato microtuber produced in vitro provides a model system to investigate photoperiod-dependent tuberization. However, the genes associated with potato tuberization remain to be elucidated. The present research involved three potato clones with distinct tuberization response to changes of photoperiod. Digital Gene Expression (DGE) Tag Profiling analysis of the short-day-sensitive clone identified 2218 genes that were regulated by day length. Both GO and KEGG pathway analysis provided insights into predominant biological processes and pathways, and enabled the selection of 56 genes associated with circadian rhythmicity, signal transduction, and development. Quantitative transcriptional analysis in the selected clones revealed 5 genes potentially associated with photoperiodic tuberization, which were predicted to encode a DOF protein, a blue light receptor, a lectin, a syntaxin-like protein, and a protein with unknown function. Our results strongly suggest that potato tuberization may be largely controlled by the homologs of genes shown to regulate flowering time in other plants.

Identification and molecular characterization of a chitin deacetylase from Bombyx mori peritrophic membrane.

The insect midgut epithelium is generally lined with a unique chitin and protein structure, the peritrophic membrane (PM), which facilitates food digestion and protects the gut epithelium. PM proteins are important determinants for PM structure and formation. In this study, the silkworm Bombyx mori midgut PM protein BmCDA7 was identified by proteomic tools. The full-length BmCDA7 cDNA is 1357 bp; the deduced protein is composed of 379 amino acid residues and includes a 16 amino acid residue signal peptide, a putative polysaccharide deacetylase-like domain and 15 cysteine residues present in three clusters. The heterologously expressed proteins of the BmCDA7 gene in yeast displayed chitin deacetylase activity. Expression of B. mori BmCDA7 was detected in the midgut at both the transcriptional and translational levels. The BmCDA7 gene was expressed by the newly hatched silkworm larvae until day seven of the fifth instar and was expressed at a high level in the newly exuviated larvae of different instars. The functions and regulatory mechanism of BmCDA7, however, need further investigation.

Simultaneous mitigation of heterocyclic aromatic amines and advanced glycation end products in roasted beef patties by plasma-activated water: Effects and mechanisms.

Heterocyclic aromatic amines (HAAs) and advanced glycation end products (AGEs) are hazardous substances produced when food is heated. In this study, the ability of plasma-activated water (PAW) to simultaneously mitigate production of HAAs and AGEs in roasted beef patties was investigated. Assays of free radicals, lipid peroxidation, and active carbonyls were used to analyze the mechanisms. PAW treatment decreased the contents of free HAAs, free AGEs, bound HAAs, and bound AGEs to 12.65 ng/g, 0.10 µg/g, 297.74 ng/g, and 4.32 µg/g, with the inhibition rates of 23.88%, 23.08%, 11.02%, and 8.47%, respectively. PAW treatment decreased HAAs and AGEs and mitigated their increase during storage. The decrease of HAAs and AGEs in PAW-treated samples was correlated with the enhancement of antioxidant capacity. The increase of free radical scavenging ability by PAW treatment led to the decrease of lipid peroxidation and the decrease of active carbonyls, HAAs, and AGEs in meat products.

Sub-Nanogram Resolution Measurement of Inertial Mass and Density Using Magnetic-Field-Guided Bubble Microthruster.

Artificial micro/nanomotors using active particles hold vast potential in applications such as drug delivery and microfabrication. However, upgrading them to micro/nanorobots capable of performing precise tasks with sophisticated functions remains challenging. Bubble microthruster (BMT) is introduced, a variation of the bubble-driven microrobot, which focuses the energy from a collapsing microbubble to create an inertial impact on nearby target microparticles. Utilizing ultra-high-speed imaging, the microparticle mass and density is determined with sub-nanogram resolution based on the relaxation time characterizing the microparticle's transient response. Master curves of the BMT method are shown to be dependent on the viscosity of the solution. The BMT, controlled by a gamepad with magnetic-field guidance, precisely manipulates target microparticles, including bioparticles. Validation involves measuring the polystyrene microparticle mass and hollow glass microsphere density, and assessing the mouse embryo mass densities. The BMT technique presents a promising chip-free, real-time, highly maneuverable strategy that integrates bubble microrobot-based manipulation with precise bioparticle mass and density detection, which can facilitate microscale bioparticle characterizations such as embryo growth monitoring.

Phototransformation determines the fate of 5-fluorouracil and cyclophosphamide in natural surface waters.

The use of cytotoxic substances, such as 5-fluorouracil and cyclophosphamide, is carefully controlled; however, these medications may still enter bodies of water through wastewater discharge. These substances may pose risks to stream and river life, as well as to humans via drinking water. In this study, the photochemical fate of 5-fluorouracil and cyclophosphamide was investigated in synthetic waters and four river waters and was found to be the most important attenuation process for each entity in natural surface waters. Bicarbonate alone was found to react with the excited states of 5-fluorouracil, thus enhancing direct photolysis rates. In the presence of nitrate and significant amounts of bicarbonate (close to 2 mM), 5-fluorouracil was rapidly removed (within 1 day) through indirect photolysis. In contrast, natural attenuation was of low importance for cyclophosphamide in most surface waters studied. A long, shallow river or lake with a long residence time (>7 days), very low alkalinity, and significant nitrate levels (>5 mg-N L(-1)) may be an exception. The phototransformation product of 5-fluorouracil was also identified. However, the total organic carbon experiments yielded important results: photolysis resulted in quick transformation of 5-fluorouracil but minimal mineralization. Additional studies of the toxicity of photobyproducts of 5-fluorouracil are needed to determine the true risk to human health of 5-fluorouracil contamination of surface water, given its near-total photodegradation and resultant, deceptively low detection rate in surface waters.

Cysteine-modified orange peel for removal of Cu(II) from aqueous solutions.

In the present work, cysteine-modified orange peel (COP) for the removal of Cu(II) from aqueous solutions has been developed and comparatively studied with diethylenetriamine-modified orange peel (DOP). Both COP and DOP were systematically evaluated via their capabilities for adsorbing Cu(II), including the key influential parameters such as initial pH, contact time and initial Cu(II) concentration. Further studies suggest that the sorption of Cu(II) onto both COP and DOP fits well with the pseudo-second-order equation, and the corresponding sorption isotherm can be classified to a Langmuir isotherm model. COP appears more advantageous over DOP and far better than that of unmodified OP in removal of Cu(II) from aqueous system. The maximum capacities of COP and DOP for adsorbing Cu(II) are 95.23 and 83.68 mg/g, respectively, about three times higher than that of unmodified OP. The sorption efficiency of COP drops by merely about 3% after five cycles, implying a promising usage in the removal of Cu(II) from wastewater in practice.

Two-dimensional measurements of receptor-ligand interactions.

Gaining insight into the two-dimensional receptor-ligand interactions, which play a significant role in various pivotal biological processes such as immune response and cancer metastasis, will deepen our understanding of numerous physiological and pathological mechanisms and contribute to biomedical applications and drug design. A central issue involved is how to measure the in situ receptor-ligand binding kinetics. Here, we review several representative mechanical-based and fluorescence-based methods, and briefly discuss the strengths and weaknesses for each method. In addition, we emphasize the great importance of the combination of experimental and computational methods in studying the receptor-ligand interactions, and further studies should focus on the synergistic development of experimental and computational methods.

Biochemical, histopathological and untargeted metabolomic analyses reveal hepatotoxic mechanism of acetamiprid to Xenopus laevis.

Acetamiprid, a commonly detected neonicotinoid in aquatic ecosystems, poses a threat to aquatic non-target organisms. However, limited information is available on the toxic effects of acetamiprid on nontarget aquatic organisms. This study assessed the toxic effects of acetamiprid on Xenopus laevis, a typical model organism. The acute toxicity for 96 h revealed that acetamiprid had detrimental effects with a median lethal concentration (LC50) value of 64.48 mg/L. Toxicity assays, including oxidative stress, histopathology and untargeted metabolomics of acetamiprid to X. laevis, were performed for 28 d at 1/10 and 1/100 LC50 by studying the liver, which is the most antioxidant and major metabolic organ. The results demonstrated that acetamiprid exposure significantly changed the oxidant status of and caused histological damage to the liver. Furthermore, the untargeted metabolomic analysis based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) identified the endogenous metabolites that were significantly altered. There were 89 differential metabolites compared to the controls: 64 in the 1/10 LC50 group, 47 in the 1/100 LC50 group, and 23 metabolites in the 1/10 LC50 group were the same as those in the 1/100 LC50 group. Sixteen pathways that were mainly associated with amino acid metabolism and lipid metabolism, such as sphingolipid metabolism, glycerophospholipid metabolism and histidine metabolism, were disrupted, revealing the hepatotoxic effects of acetamiprid on X. laevis at the molecular level. These findings provide crucial information for evaluating the aquatic risks of neonicotinoids.

Insight into adsorption process and mechanisms of Cr(III) using carboxymethyl cellulose-g-poly(acrylic acid-co-acrylamide)/attapulgite composite hydrogel.

Cr(III) as one of the most concerned potentially toxic elements, is discharged from relevant industries and Cr(VI) reduction. Hydrogel-based adsorption could be one of the promising approaches for Cr(III) removal. Featured with environmental friendliness and low cost, carboxymethyl cellulose (CMC) was employed for the hydrogel synthesis, and attapulgite (APT) could be used to strengthen its stability. However, the adsorption performance and mechanisms need to be examined. In the present study, carboxymethyl cellulose-g-poly(acrylic acid-co-acrylamide)/ attapulgite (CMC-g-p(AA-co-AM)/APT) was synthesised via in situ copolymerisation. Its efficacy for removing Cr(III) from an aqueous solution was investigated using batch adsorption experiments. Results showed that the introduction of APT enhanced the thermal stability but decreased the swelling performance of the hydrogel. The prepared hydrogel could strongly adsorb Cr(III) at a wide pH range of 3.0-7.0. Cr(III) can be efficiently removed by the composite hydrogel within 1-2 h. At low concentration, CMC-g-p(AA-co-AM)/APT could slightly adsorbed more Cr(III) than CMC-g-p(AA-co-AM). The maximum absorption of CMC-g-p(AA-co-AM) and CMC-g-p(AA-co-AM)/APT were 74.8 and 47.7 mg/g at 298 K, respectively. The negative value of ΔHo and ΔGo indicated the adsorption of Cr(III) onto the two studied hydrogels is an exothermic and spontaneous process. Ion exchange and complexation, as implied by EDS, FT-IR and XPS, combining with electrostatic attraction are the possible adsorption mechanisms for Cr(III) onto the prepared hydrogels. All the results above suggests that the composite hydrogel CMC-g-p(AA-co-AM)/APT can be a promising candidate for the removal of Cr(III) from waste water.

Cross-reactive antibodies against monkeypox virus exist in the population immunized with vaccinia Tian Tan strain in China.

Monkeypox virus (MPXV) belongs to the Orthopoxvirus genus. The worldwide outbreak of MPXV in 2022 has caused widespread concerns. Cross-reactive antibodies induced by vaccinia-inoculation can provide protection against reinfection by MPXV. The vaccinia Tian Tan (VTT) strain, which was widely inoculated in the Chinese population before the 1980s, has genomic differences from other vaccinia strains, although they all belong to the orthopoxviruses family. The current seroprevalence of VTT-vaccinated populations remains unclear more than four decades after the termination of vaccination campaigns in China. Our results showed that cross-reactive IgG antibodies against MPXV were present in 31.8% (75/236) of vaccinees four decades after VTT-vaccination, suggesting that vaccination with VTT may provide long-term protection against MPXV infection in some individuals.

Phototransformation of cephalosporin antibiotics in an aqueous environment results in higher toxicity.

Photodegradation may be the most important elimination process for cephalosporin antibiotics in surface water. Cefazolin (CFZ) and cephapirin (CFP) underwent mainly direct photolysis (t(1/2) = 0.7, 3.9 h), while cephalexin (CFX) and cephradine (CFD) were mainly transformed by indirect photolysis, which during the process a bicarbonate-enhanced nitrate system contributed most to the loss rate of CFX, CFD, and cefotaxime (CTX) (t(1/2) = 4.5, 5.3, and 1.3 h, respectively). Laboratory data suggested that bicarbonate enhanced the phototransformation of CFD and CFX in natural water environments. When used together, NO(3)(-), HCO(3)(-), and DOM closely simulated the photolysis behavior in the Jingmei River and were the strongest determinants in the fate of cephalosporins. TOC and byproducts were investigated and identified. Direct photolysis led to decarboxylation of CFD, CFX, and CFP. Transformation only (no mineralization) of all cephalosporins was observed through direct photolysis; byproducts were found to be even less photolabile and more toxic (via the Microtox test). CFZ exhibited the strongest acute toxicity after just a few hours, which may be largely attributed to its 5-methyl-1,3,4-thiadiazole-2-thiol moiety. Many pharmaceuticals were previously known to undergo direct sunlight photolysis and transformation in surface waters; however, the synergistic increase in toxicity caused by this cocktail (via pharmaceutical photobyproducts) cannot be ignored and warrants future research attention.

[Measuring the density of wood and bamboo using computed tomography].

CT is widespread non-destructive detection technique for wood materials, and the density measurement is a key role during this application. In the present report, the use of CT for air-dry density measurement of wood and bamboo is described. The authors found that there were marked linear correlations between air-dry density (0.303-1.061 g x cm(-3)) of 24 kinds of woods and their respective CT value, as well as 25 kinds of lignin materials (including 24 kinds of woods and 1 kind of bamboo) and the CT value, both with correlation coefficient of 0.99, which belonged to the CT technological breakthrough for wood quantitative detection These research results show that CT is an appropriate way to measure density for wood and bamboo, and would provide technical support for CT used in the field of wood science research and wood processing.

Montelukast Inhibits HCoV-OC43 Infection as a Viral Inactivator.

Coronaviruses (CoVs) consist of a large group of RNA viruses causing various diseases in humans and in lots of animals. Human coronavirus (HCoV) OC43, the prototype of beta-coronavirus discovered in the 1960s, has been circulating in humans for long time, and infection with other emerging strains of beta-coronavirus (SARS-CoV, SARS-CoV-2, and MERS-CoV) can lead to severe illness and death. In this study, we found that montelukast, a leukotriene receptor antagonist, potently inhibited the infection of HCoV-OC43 in distinct cells in a dose- and time- dependent manner. Additionally, the results showed that montelukast induced release of HCoV-OC43 genomic RNA by disrupting the integrity of the viral lipid membrane, and irreversibly inhibited viral infection. Considering the similarity among HCoV-OC43, MERS-CoV, and SARS-CoV-2, it suggests that montelukast may be a potential candidate for the treatment of human beta-coronavirus infection.

Erythromycin Estolate Is a Potent Inhibitor Against HCoV-OC43 by Directly Inactivating the Virus Particle.

In addition to antibacterial effects, macrolide antibiotics exhibit other extensive pharmacological effects, such as anti-inflammatory and antiviral activities. Erythromycin estolate, one of the macrolide antibiotics, was previously investigated to effectively inhibit infections of various flaviviruses including Zika virus, dengue virus, and yellow fever virus, but its antiviral effect against human coronavirus remains unknown. Thus, the current study was designed to evaluate the antiviral efficacy of erythromycin estolate against human coronavirus strain OC43 (HCoV-OC43) and to illustrate the underlying mechanisms. Erythromycin estolate effectively inhibited HCoV-OC43 infection in different cell types and significantly reduced virus titers at safe concentration without cell cytotoxicity. Furthermore, erythromycin estolate was identified to inhibit HCoV-OC43 infection at the early stage and to irreversibly inactivate virus by disrupting the integrity of the viral membrane whose lipid component might be the target of action. Together, it was demonstrated that erythromycin estolate could be a potential therapeutic drug for HCoV-OC43 infection.

The Effect of Non-Cognitive Ability on Farmer's Ecological Protection of Farmland: Evidence from Major Tea Producing Areas in China.

Ecological protection of farmland is an important means to reduce agricultural non-point source pollution and improve the quality of agricultural products. As the main body of current agricultural production and operation, the aging labor force has insufficient cognitive ability and low ability to learn actively, which is not conducive to transforming the green output. However, non-cognitive abilities closely related to the acquired environment can promote the elderly farmers' farmland ecological protection behavior by improving life satisfaction and social adaptability. Based on the above background, using the survey data of 964 farmers in China, the bivariate Probit model was used to empirically test the influence mechanism of non-cognitive ability on the ecological protection behavior of farmland. The study found that non-cognitive ability significantly promoted farmer's ecological protection of farmland in China. Specifically, the variables of non-cognitive ability, social communication ability, active learning ability, self-efficacy, stress resistance, altruistic tendency and individual resilience were found to significantly promote ecological protection of farmland. Mechanism analysis showed that non-cognitive ability promoted the ecological protection behavior of farmland by expanding social capital, information channels and improving technical value perception. A heterogeneity analysis revealed that non-cognitive ability had a greater impact on ecological protection behavior of farmland in the elderly and low-income groups. Therefore, government should attach importance to improving farmers' non-cognitive abilities, further increase technical publicity, and build a communication platform for farmers in order to promote the ecological protection of farmland.