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Combined antihypertensive therapy has obvious advantages over single drug therapy. Hypertension guidelines fully affirm the efficacy of dual combination in initial antihypertensive therapy. Recent studies have also pointed out that the quadruple combination of very low-dose antihypertensive drugs is superior to single drugs. However, whether low-dose quadruple therapy is better than dual combination is unknown. To evaluate and compare the efficacy and safety of half-dose quadruple therapy vs standard-dose dual therapy in the initial treatment of hypertensive patients with systolic/diastolic blood pressure 140-179/90-109 mm Hg. A randomized double-blind crossover clinical trial will be conducted to compare the efficacy and safety of low-dose quadruple antihypertensives (irbesartan 75 mg + metoprolol 23.75 mg + amlodipine 2.5 mg + indapamide 1.25 mg) with standard-dose dual antihypertensives (irbesartan 150 mg + amlodipine 5 mg) in the initial treatment of patients with mild to moderate hypertension (140-179/90-109 mm Hg). Ninety patients are required and will be recruited and randomly assigned in a 1:1 ratio to 2 crossover groups. Two groups will receive a different combination therapy for 4 weeks, then switch to the other combination therapy for 4 weeks, with a 2-week wash-out. The patients will be followed up for 4 weeks to compare the antihypertensive effects and related adverse effects of the 2 antihypertensive combination treatments. We present the rationale for the design of the QUADUAL trial. The trial started in July 2022 and is expected to be completed by August 2023. The study aims to evaluate if an initial treatment regimen of quadruple combination of half-dose blood pressure medications will result in greater reduction in blood pressure and fewer side effects compared to standard dose dual therapy. www.clinicaltrials.gov (NCT05377203). [ABSTRACT FROM AUTHOR]

An updated understanding of global prevalence of primary aldosteronism (PA) is essential for the development of primary prevention and management strategies for PA. We aimed to provide update global and regional prevalence of PA and to evaluate cardiovascular risk of PA compared to essential hypertension (EH). We systematically searched PubMed, Web of Science, and Embase for studies on the prevalence of PA or cardiovascular risk of PA published up to July 31, 2022 for this meta-analysis. Global prevalence of PA was calculated using random-effects inverse-variance models and cardiovascular risk of PA was estimated using random-effects models. We identified 39 articles for meta-analysis of PA prevalence, and 13 articles were included in the meta-analysis of cardiovascular risk. Global prevalence of PA was 9.4% (95% CI: 8.3-10.5), with a higher prevalence in males than in females. Prevalence of PA was higher in the South-East Asia than in other regions, and higher in lower middle-income countries than in other economic levels, with greater country-specific differences. Compared with EH, PA had an increased risk of coronary artery disease (OR=1.88, 95% CI: 1.41-2.50), stroke (OR=2.50, 95% CI: 2.08-3.02), heart failure (OR=2.06, 95% CI: 1.33-3.19), and atrial fibrillation (OR=3.17, 95% CI: 2.09-4.80). The management of the increasing number of patients with PA and its associated burden of cardiovascular disease is likely to place increasing pressure on health systems. Early detection of PA is essential to reduce the associated burden, especially in areas where the assessment of PA has not received sufficient attention. [ABSTRACT FROM AUTHOR]

The functional links of specific retinoid receptors to early developmental events in the avian embryo are not known. Before such studies are undertaken, knowledge is required of the spatiotemporal expression patterns of the receptor genes and their regulation by endogenous retinoic acid levels during the early stages of development. Here, we report the expression patterns of mRNAs for RAR[alpha], RAR[alpha], RAR[beta]2, RAR[gamma], RAR[gamma]2, RXR[alpha], and RAR[gamma] from neurulation to HH10 in the normal and vitamin A-deficient (VAD) quail embryo. The transcripts for all retinoid receptors are detectable at HH5, except for RXR[gamma], which is detected at the beginning of HH6. At the 4/5 somite stage of HH8, when retinoid signaling is initiated in the avian embryo, mRNAs of all receptors are present, with very strong and ubiquitous expression patterns for RAR[alpha], RAR[alpha]2, RAR[gamma], RAR[gamma]2, and RXR[alpha], a persistent expression of RAR[gamma] in the neural tissues, a strong expression of RAR[beta]2 in lateral plate mesoderm and somites, and an anterior expression of RXR[gamma]. All retinoid receptors are expressed in the heart primordia. In the VAD quail embryo, the general pattern of retinoid receptor transcript localization is similar to that of the normal, except that the expression of RAR[alpha]2 and RAR[beta]2 is severely diminished. Administration of retinol or retinoic acid to VAD embryos at or before the 4/5 somite stage rescues the expression of RAR[alpha]2 and RAR[beta]2 within approximately 45 min and restores normal development. RAR[beta]2 expression requires the expression of RAR[alpha]2. After neurulation, the expression of all retinoid receptors in the VAD quail embryo becomes independent of vitamin A status and is similar to that of the normal. The mRNA levels and sites of expression of the key enzyme for retinoic acid biosynthesis, Raldh-2, are not affected by vitamin A status; the expression pattern is restricted and does not correspond to that of retinoid receptors at all sites. The general patterns and intensity of retinoid receptor gene expression during early quail development are comparable to those of the mammalian and thus validate the application of results from retinoid-regulated avian development studies to those of the mammalian. Keywords: Vitamin A requirement; Quail embryo; Early development; Retinoid receptor transcripts; Induction by retinoids; In ovo rescue

Hypertensive disorders in pregnancy (HDP) constitute a worldwide health problem for pregnant women and their infants. This study provided HDP burden over 1990 to 2019 by region and age distribution, and predicted changes in related values for the next 25 years. We then conducted an econometric analysis of the author distribution, collaborative networks, keyword burst clustering, and spatio-temporal analysis of HDP-related publications from 2012 to 2022 to access current scientific developments and hotspots. The number of pregnant women with HDP has been increasing over the past 30 years, with regional and age-stratified differences in the burden of disease. Additionally, projections suggest an increase of deaths due to maternal HDP among adolescents younger than 20 years. Current research is mostly centered on pre-eclampsia, with hot keywords including trophoblast, immune tolerance, frozen-thawed embryo transfer, aspirin, gestational diabetes association, and biomarkers. Researches on the pathological mechanism, classification, and subtypes of HDP need to be further advanced. [ABSTRACT FROM AUTHOR]

Vitamin A-deficient (VAD) quail embryos have severe abnormalities, including a high incidence of reversed cardiac situs. Using this model we examined in vivo the physiological function of vitamin A in the left/right (L/R) cardiac asymmetry pathway. Molecular analysis reveals the expression of early asymmetry genes activin receptor IIa, sonic hedgehog, Caronte, Lefty-1, and Fgf8 to be unaffected by the lack of retinoids, while expression of the downstream genes nodal-related, snail, related (cSnR), and Pitx2 is altered. In VAD embryos nodal expression in left lateral plate mesoderm (LPM) is severely downregulated and the expression domain altered during neurulation. Similarly, the expression of cSnR in the right LPM and of Pitx2 in the left side posterior heart-forming region (HFR) is downregulated in the VAD embryos. The lack of retinoids does not cause randomization or ectopic expression of nodal, cSnR, or Pitx2. At the six- to eight-somite stage nodal is expressed transiently in the left posterior HFR of normal quail embryos; this expression is missing in VAD embryos and may be linked to the loss of Pitx2 expression in this region of VAD quail embryos. Administration of retinoids to VAD embryos prior to the six-somite stage rescues the expression of nodal, cSnR, and Pitx2 as well as the randomized VAD cardiac phenotype. There is an absolute requirement for retinoids at the four- to five-somite developmental window for cardiogenesis and cardiac L/R specification to proceed normally. We conclude that retinoids do not regulate the left/right-specific sidedness assignments for expression of genes on the vertebrate cardiac asymmetry pathway, but are required during neurulation for the maintenance of adequate levels of their expression and for the development of the posterior heart tube and a loopable heart. Cardiac asymmetry may be but one of several critical events regulated by retinoid signaling in the retinoid-sensitive developmental window. [C] 2000 Academic Press Key Words: retinoid deficiency; quail embryo; cardiac asymmetry; Car; Lefty-1; nodal; cSnR; Pitx2; Fgf8.

This paper presents a multistable variable cross-section laminate (MVCL), which is designed by applying the displacement constraint at the two opposing ends of the laminate. A theoretical model describing the MVCL as rigid bars connected with compliant hinges is built to predict the equilibrium configurations and snap-through loads of the MVCL. The snap-through process of the multistable structure is investigated via experiment and finite element analysis (FEA). Subsequently, the theoretical model is improved by simplifying the middle segment of the MVCL as an elastic beam. Good agreement is obtained between the experimental test, FEA, and improved theoretical model results. It is shown that the current approach can be successfully applied to predict the equilibrium configurations and snap-through loads of an MVCL. The snap-through loads can be adjusted by changing the middle segment length of an MVCL. [ABSTRACT FROM AUTHOR]

With the 3:1 internal resonance, the primary and secondary resonances of an axially moving thin circular cylindrical panel are investigated in the present work. The governing equation and the compatibility equation are established based on the Donnell's nonlinear shell theory and solved to obtain the nonlinear steady-state responses by combining the Galerkin method and the method of multiple scales. The analytical solutions are verified by numerical solutions based on the Runge-Kutta Method. The governing equation includes both the quadratic nonlinearity and the cubic nonlinearity, so the perturbation solutions need to consider three time scales. The quadratic nonlinearity causes the softening behavior of the system. Natural frequencies and the 3:1 internal resonance condition are obtained by the linear analysis. Under the primary resonance, the internal resonance causes the coupling of the first two modes to complicate the nonlinear dynamic response. The response for the second mode possesses an extra bulge or peak due to the internal resonance. The quadratic nonlinearity results in the zero frequency drift and the second-order harmonic. Under the secondary resonance, the exciting force only arouses the second mode. Results are shown to examine the effects of the internal resonance, the exciting force and viscous damping coefficients on the nonlinear dynamic response of an axially moving thin circular cylindrical panel. • Axially moving circular cylindrical panels is non-linearly modeled. • Both primary and secondary resonances under 3:1 internal resonance are investigated. • Energy transfer among first two modes，zero frequency drift and second-order harmonic is found. [ABSTRACT FROM AUTHOR]

This paper lays stress on the equilibrium configurations analysis of a bi-stable unit composed of two cantilever beams with lateral post-buckling deformations. Two equilibrium configurations of the unit are described by deformations of the cantilever beam which is subjected to a shear force and has a boundary condition of zero-twist at the cantilever end. An analytical model based on the perturbation method was established for accurate post-buckling analysis of the beams. Experiments and numerical studies validate the analytical solutions on slender beams. Geometric parameters analysis on beam deformations demonstrates the application and limitation of the theoretical model. Finally, a multi-stable structure assembled by such bi-stable unit is illustrated, whose shapes are predicated by the analytical method. These results can be used to guide the design of shape reconfigurable structures with adjustable mechanical properties. [ABSTRACT FROM AUTHOR]

In this paper, a concave-shaped unit composed of two thin-walled beams with cantilever boundary conditions is designed and fabricated. Forces are introduced through the two cantilever ends of the beams whose constraints are hinged joints to get a bi-stable axial or lateral buckled unit. Initial buckling deformations of the concave-shaped units are analyzed theoretically and numerically. Experimental and numerical methods are used to investigate the post-buckling deformations and snap-through behaviors, when the concave-shaped units are axial buckled or lateral buckled. In the case of completing downwards and upwards snapping processes, there is a hysteresis loop in the force–displacement curve for the bi-stable lateral buckled unit, while is not for the bi-stable axial buckled unit. Finally, the influence of transverse displacements and dimension parameters on the snap-through behaviors of the bi-stable lateral buckled units is studied by the simulation method. • A bi-stable lateral buckled unit is designed and fabricated. • There are two symmetric modes for the initial buckled concave-shaped unit. • Post-buckling and snap-through behaviors of the bi-stable units are investigated. • The energy dissipation capacities are influenced by beams parameters. • The assembly bi-stable units are good candidates for energy-related applications. [ABSTRACT FROM AUTHOR]

• 3D DVH lattices with multi-materials were designed and fabricated. • Poisson's ratios and thermal expansion coefficients of the structure are tuned. • Coupled negative Poisson's ratio and CTE are simultaneously achieved. Natural materials have achieved excellent comprehensive mechanical properties and fascinating synergistic functionalities through composite architectures and optimum materials distribution within a single tissue during natural selection/adaptation. Producing three-dimensional (3D) architectures with multi-materials has been a major challenge in artificial materials. Herein, 3D double-V hierarchical (DVH) lattices with multi-materials were designed and fabricated using interlocking assembly strategy. Theoretical analysis, numerical simulation and experimental verification were conducted to investigate the mechanical response of the multi-material metastructures, especially effective Poisson's ratio and coefficient of thermal expansion (CTE). The results revealed that the equivalent Poisson's ratio of the 3D DVH lattices can be tuned by changing not only the geometric parameters but also the relative stiffness of the two V segments. Poisson's ratio of the multi-material metamaterials has the minimum/maximum value at transition point and tends to zero with the increase or decrease of the relative stiffness. The equivalent CTE of concave 3D DVH lattices can be tuned by changing not only the geometric parameters but also the relative CTE and relative stiffness of the two V segments from magnified positive to near zero or large negative. Coupled negative Poisson's ratio and CTE, which are hardly found in natural materials, are easily achieved by the architected DVH composite lattices. This work provides an innovative approach for the design, fabrication and characterization of 3D architected cellular materials with simultaneously tailorable auxetic behavior and thermal expansion, which are promising in advanced engineering applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The resulting oscillation of bi-stable hybrid symmetric laminate could enable broadband energy harvesting via piezoelectric transduction. The aim of this work is to investigate its dynamic behaviors to provide the basis for designing broadband energy harvester. This paper proposes the dynamic analysis of this bi-stable laminate, focusing on the intra-well dynamics around its stable states and the inter-well dynamics between two stable states. Two types of stacking sequence are performed for this bi-stable laminate, and experimental testing with different harmonic excitations is carried out for each type of this bi-stable laminate. The strain responses at three positions are monitored to investigate the dynamic responses. A finite element model is also developed to analyze the static strain distribution and capture the dynamics. The results show that the laminates exhibit intra-well response under low-level excitation, and the inter-well response at a particular range frequency appears when excitation level increases. Different types of inter-well response mode involving the snap-through behavior are obtained in experiments, such as intermittent inter-well vibration and chaotic vibration. The presented results essentially highlight the need for considering the stacking sequence associated with the dynamics while designing the hybrid bi-stable symmetric laminate to obtain the desirable nonlinear response. [ABSTRACT FROM AUTHOR]

n-Butanol is an important bulk chemical. Commercial fermentative production of n-butanol has been applied more than 100 years ago but is currently more costly than production from propylene and syngas. Renewed interest in biobutanol as a biofuel has spurred technological advances to the fermentation process. This article reviewed the recent status including the commercialization, pilot production and R&D activities of n-butanol fermentation in China. Long-term bio-production of n-butanol as a next generation biofuel and biochemical from biomass waste and steel mill off-gas needs technology breakthroughs and more environmental concerns from policymakers. [ABSTRACT FROM AUTHOR]

Clostridium ljungdahlii is a representative autotrophic gas-fermenting acetogen capable of converting CO 2 and CO into biomass and multiple metabolites. The carbon fixation and conversion based on C. ljungdahlii have great potential for the sustainable production of bulk biochemicals and biofuels using industrial syngas and waste gases. With substantial recent advances in genetic manipulation tools, it has become possible to study and improve the metabolic capability of C. ljungdahlii in gas fermentation. The product scope of C. ljungdahlii has been expanded through the introduction of heterologous production pathways followed by the modification of native metabolic networks. In addition, progress has been made in understanding the physiological and metabolic mechanisms of this anaerobe, contributing to strain designs for expected phenotypes. In this review, we highlight the latest research progresses regarding C. ljungdahlii and discuss the next steps to comprehensively understand and engineer this bacterium for an improved bacterial gas bioconversion platform. [ABSTRACT FROM AUTHOR]

The development of hypertension involves extensive arterial wall remodeling, in which cysteine proteases play an essential role. Cathepsin L/V has been reported to be a cysteine protease that is closely intertwined with the tissue inflammatory response and extracellular matrix accumulation, allowing it to regulate arterial remodeling. The aim of this study was to determine the role of cathepsin L/V and its regulatory pathway in vascular remodeling in hypertension. We showed that cathepsin L/V and its endogenous inhibitor cystatin C, as well as mitogen-activated protein kinase (MEK) phosphorylation, were upregulated in the mesenteric arteries and serum of hypertensive patients. Using a model of angiotensin II-induced hypertension, we observed an increase in aortic artery media thickness, cathepsin L activity, blood pressure and MEK phosphorylation. Treatment with the cathepsin L inhibitor Z-FF-FMK or the genetic deletion of cathepsin L significantly attenuated angiotensin II-induced hypertension, arterial remodeling, cathepsin L activation and MEK phosphorylation. In addition, siRNA-cathepsin V significantly blocked angiotensin II-induced MEK and extracellular signal–regulated kinase (ERK) phosphorylation but not cell proliferation in human aortic smooth muscle cells (HASMCs). Further treatment with the ERK phosphorylation inhibitor U0126 also blocked angiotensin II-induced HASMCs proliferation. The results indicate that the inhibition of cathepsin L prevents arterial remodeling and hypertension, in part by inhibiting the MEK-ERK signaling-mediated regulation of smooth muscle cell proliferation in the vessel wall. • Blocking cathepsin L/V significantly attenuates angiotensin II- induced hypertension and arterial remodeling. • The mechanism relies on inhibiting MEK-ERK signaling in regulating of SMC proliferation in the vessel wall. • Cathepsin L/V as a novel target in regulating the arterial remodeling and hypertension is proposed. [ABSTRACT FROM AUTHOR]

Industrial biotechnology is reliant on native pathway engineering or foreign pathway introduction for efficient biosynthesis of target products. Chromosomal integration, with intrinsic genetic stability, is an indispensable step for reliable expression of homologous or heterologous genes and pathways in large-scale and long-term fermentation. With advances in synthetic biology and CRISPR-based genome editing approaches, a wide variety of novel enabling technologies have been developed for single-step, markerless, multi-locus genomic integration of large biochemical pathways, which significantly facilitate microbial overproduction of chemicals, pharmaceuticals and other value-added biomolecules. Notably, the newly discovered homology-mediated end joining strategy could be widely applicable for high-efficiency genomic integration in a number of homologous recombination-deficient microbes. In this review, we explore the fundamental principles and characteristics of genomic integration, and highlight the development and applications of targeted integration approaches in the three representative industrial microbial systems, including Escherichia coli , actinomycetes and yeasts. [ABSTRACT FROM AUTHOR]

Solventogenic clostridia, a group of important industrial microorganisms, have exceptional substrate and product diversity, capable of producing a series of two-carbon and even long-chain chemicals and fuels by using various substrates, including sugars, cellulose and hemicellulose, and C1 gases. For the sake of in-depth understanding and engineering these anaerobic microorganisms for broader applications, studies on metabolic regulation of solventogenic clostridia had been extensively carried out during the past ten years, based on the rapid development of various genetic tools. To date, a number of regulators that are essential for cell physiological and metabolic processes have been identified in clostridia, and the relevant mechanisms have also been dissected, providing a wealth of valuable information for metabolic engineering. Here, we reviewed the latest research progresses on the metabolic regulation for chemical production and substrate utilization in solventogenic clostridia, by focusing on three typical Clostridium species, the saccharolytic C. acetobutylicum and C. beijerinckii , as well as the gas-fermenting C. ljungdahlii . On this basis, future directions in the study and remodeling of clostridial regulation systems, were proposed for effective modification of these industrially important anaerobes. [ABSTRACT FROM AUTHOR]

Bioconversion of C1 gases to produce chemicals has good application prospects. Here, the combination of trace metals optimization using a statistical method with variable-temperature cultivation was used to enhance alcohol synthesis during CO-rich off-gas fermentation by Clostridium carboxidivorans P7. Based on ATCC medium 1754, the optimum concentration of the trace metals was found to be 5-fold Ni 2+ , Co 2+ , SeO 4 2+ , and WO 4 2+ ; 3.48-fold Cu 2+ ; 0.55-fold MoO 4 2+ ; 0.5-fold Zn 2+ and (NH 4 ) 2 SO 4 ·FeSO 4 ·6H 2 O; and additional 44.32 μM FeCl 3 ·6H 2 O. The production of alcohol and organic acid changed to 4.40 g/L and 0.50 g/L from 2.16 g/L and 2.37 g/L, respectively, yielding an increase of alcohol-to-product ratio from 47.7% to 89.8%. By fermenting with the optimized medium and timed control of the incubation temperature (37 °C [0–24 h]–25 °C [24–144 h]), the alcohol titre further increased to 6.97 g/L with 1.67 g/L butanol and 1.33 g/L hexanol, exceeding those previously reported for strain P7. [ABSTRACT FROM AUTHOR]

Solventogenic clostridia are native producers of ethanol and many higher alcohols employing a broad range of cheap renewable substrates, such as lignocellulosic materials and C1 gases (CO and CO 2 ). These characteristics enable solventogenic clostridia to act as flexible microbial platforms for the production of liquid biofuels. With the rapid development of genetic tools in recent years, the intrinsic intractability of clostridia has been largely overcome, thus, engineering clostridia for production of chemicals and fuels has attracted increasing interests. Here, we provide an overview of recent progress in the production of alcohols based on solventogenic clostridia. Saccharolytic, cellulolytic and gas-fermenting clostridia are discussed, with a special focus on strategies for metabolic engineering to enable and to improve clostridia for the production of higher alcohols. [ABSTRACT FROM AUTHOR]

The article presents case report of a patient who suffered hemangioendothelioma of the cervical spine. The female patient was presented with a 12-year history of chronic, progressive cervical pain and limitation of motion localized to the cervical spine, associated with progressive quadriplegia and sensory disturbance over the previous year.

Adenoid cystic carcinoma (ACC) is a rare malignant tumor derived mainly from the salivary glands, representing approximately 1% of all headandneck carcinomasand 10% of all salivary gland neoplasms. ACC displays a paradoxical behavioral combination of an indolent growth pattern but an aggressive progression, with local recurrence and distant metastasis. The propensity of ACC of the head and neck (ACCHN) for perineural invasion and its anatomical location, especially if it extends to the nasal cavity and paranasal sinuses, facilitates tumor involvement in the surrounding structures, such as the orbit, pterygopalatine fossa, Meckel'scave, and cavernous sinus, which can lead to skull base involvement and intracranial extension. Despite advances in molecular mechanisms and diagnostic imaging, ACC treatment remainschallenging due to the lack ofconsensuson treatment patterns. In this review, we aimed toprovideanupdatedinsight intothe understanding of ACCHN by focusing on clinical behavior, imaging diagnosis, pathological features, and therapeutic strategies. We reviewed the molecular mechanisms, especially in ACCHN with perineural invasion, and elaborated on treatment options, including chemotherapy, targeted therapies, and immunotherapy, to establish a comprehensive understanding of ACC to arrive at a policy for proper diagnosis, preoperative evaluation, and therapeutic strategies. [ABSTRACT FROM AUTHOR]

Although gene disruption in Clostridium spp. with the TargeTron technology is much more effective than single-crossover integration, it cannot achieve gene modification via allelic exchange. Here, we developed a targeted, nonpolar, scarless gene modification system based on the I-SceI endonuclease. First, a replicative plasmid containing homology arms on either side of the target sequence and I-SceI recognition sites was integrated into the Clostridium chromosome, resulting in single-crossover integrants containing a mutant allele. Second, the cells were transformed with plasmids containing the synthetic gene ( sceC ) encoding the I-SceI enzyme, resulting in double-stranded breaks at the I-SceI recognition sites, which stimulated homologous recombination and yielded double-crossover mutants. Application of the method was demonstrated by deleting two genes ( adc and glcG ) from C. acetobutylicum ATCC 824 and one gene ( adc ) from C. beijerinckii NCIMB 8052, and by introducing point mutations into xylR of C. beijerinckii NCIMB 8052. The double-crossover mutants displayed similar fermentation phenotypes to those constructed with the TargeTron technology. [ABSTRACT FROM AUTHOR]

Solventogenic clostridia can produce acetone, butanol and ethanol (ABE) by using different carbohydrates. For economical reasons, the utilization of cheap and renewable biomass in clostridia-based ABE fermentation has recently attracted increasing interests. With the study of molecular microbiology and development of genetic tools, the understanding of carbohydrate metabolism in clostridia has increased in recent years. Here, we review the pioneering work in this field, with a focus on dissecting the pathways and describing the regulation of the metabolism of economical substrate-derived carbohydrates by clostridia. Recent progress in the metabolic engineering of carbohydrate utilization pathways is also described. [ABSTRACT FROM AUTHOR]

• Serum MIF levels were elevated in CRSwNP patients, especially in eCRSwNP patients. • Serum MIF was a specific biomarker for distinguishing CRSwNP endotypes. • Serum MIF levels were closely associated with mucosal eosinophil infiltration. Chronic rhinosinusitis with nasal polyps (CRSwNP) is a highly heterogeneous disease and can be categorized into eosinophilic CRSwNP (eCRSwNP) and non-eosinophilic CRSwNP (neCRSwNP). Exploring effective biomarkers to distinguish endotypes is important for personalized therapies. The present study aims to evaluate the predictive value of serum MIF in CRSwNP endotypes. One hundred and twenty CRSwNP patients, including 51 eCRSwNP and 69 neCRSwNP, 40 chronic rhinosinusitis without nasal polyps (CRSsNP) patients and 40 healthy controls (HC) were enrolled. Serum MIF levels were determined by enzyme-linked immunosorbent assay (ELISA). The patients' clinical variables were analyzed for correlations with serum MIF. Receiver operating characteristic (ROC) curve and multivariate analysis were utilized to assess the predictive value of serum MIF in CRSwNP endotypes. The serum MIF levels were significantly higher in CRSwNP group than CRSsNP group and HC group (P < 0.001), and the serum MIF levels were increased in eCRSwNP compared to neCRSwNP group (P = 0.006). Elevated serum MIF levels were significantly correlated with blood eosinophil (B-EOS) count (r = 0.411, P < 0.001), B-EOS percentage (r = 0.377, P < 0.001), visual analog scale score (r = 0.204, P = 0.025), tissue eosinophil (T-EOS) count (r = 0.705, P < 0.001) and T-EOS percentage (r = 0.671, P < 0.001) in CRSwNP patients. ROC curve demonstrated that serum MIF exhibited good preoperative prediction in CRSwNP endotypes (area under the curve = 0.925, P < 0.001). Multivariate regression analysis showed that serum MIF was an independent factor associated with CRSwNP endotypes. This was the first study identifying serum MIF as a possible specific biomarker for preoperatively distinguishing CRSwNP endotypes. Furthermore, the serum MIF levels were found to be closely associated with the degree of mucosal eosinophil infiltration. [ABSTRACT FROM AUTHOR]

Abstract: GL-7-ACA acylase (GLA) is an enzyme that converts GL-7-ACA to 7-ACA, a starting material for semi-synthetic cephalosporin antibiotics. Four his-tagged GLAs were constructed in this work different in their N-terminal amino acid residues. Among them the highest activity of GLA reached 3800U/l in 19h for the recombinant strain BL21 (DE3)/pET28GA01. The immobilized GLA on TALON affinity support, agar-EPI-IDA-Co2+ and FP-IDA-Ni2+ was evaluated by one-step purification and immobilization, and the highest immobilized activity was 163U/g for TALON affinity support. But more robust matrix made FP-IDA-Ni2+ suitable for the industrial application. The activities of four immobilized GLAs on FP-IDA-Ni2+ ranged from 66.7 to 80U/g. Immobilized GLA showed good stability at pH value below 11.0 and at temperature up to 30°C. To the consecutive conversion of GL-7-ACA, immobilized GLA was recycled 21 times without significant loss of activity, and the average yield rate of 7-ACA reached 90%. These results indicated that intracellular production of his-tagged GLA in E. coli, followed by one-step affinity purification and immobilization on FP-IDA-Ni2+ resins, might serve as an effective process for the industrial application. [Copyright &y& Elsevier]

Medically useful semisynthetic cephalosporin antibiotics are made from precursor 7-aminocephalosporanic acid (7-ACA). Cephalosporin acylase (CA), which catalyzes hydrolysis of both glutaryl-7-aminocephalosporanic acid (GL-7ACA) and cephalosporin C (CPC) to 7-ACA, is thus a very important enzyme for producing semisynthetic beta-lactam antibiotics. To facilitate the attempts of obtaining the microorganisms with higher CA activity from natural environments, a new and specific method for screening environmental microorganisms with cephalosporin acylase activity was developed. The core part of cephalosporin was replaced by 6-amino penicillinic acid (6-APA) to generate new substrates glutaryl-6-APA and adipoyl-6-APA for screening. Serratia marcescens that is sensitive to 6-APA and resistant to penicillin G, glutaryl-6-APA and adipoyl-6-APA was used as an indicator strain in an overlaid-agar screening system. A strain capable of producing cephalosporin acylase was selected from thousands of candidates by this method. Because of its specificity, simplicity and sensitivity, the method could be easily installed into a high-throughout system. [Copyright &y& Elsevier]

RNA extraction from antibiotic-producing actinomycetes can be a difficult and time-consuming process due to their special peptidoglycans cell wall composition and the short life of RNA. Hence, the rapidity of cellular lysis and complete inhibition of RNase are of particular importance for isolating intact RNA of high quality. The genus of Amycolatopsis mediterranei produces many clinically important antibiotics, such as rifamycin and vancomycin; however, the available methods for bacterial RNA isolation did not work very well with this genus. In this report, we described a new method for RNA isolation using the combination of LiCl, urea and guanidinium thiocyanate to disrupt the cell wall of Amycolatopsis. Compared with earlier published RNA isolation methods, the method gave higher yields of pure and intact RNA. About 1 μg total RNA free of DNA contamination can be obtained from 1 mg wet weight of A. mediterranei. The integrity of the RNA was demonstrated by formaldehyde agarose gel electrophoresis and Northern blot analyses. [Copyright &y& Elsevier]

• Serum activated leukocyte cell adhesion molecule levels were elevated in the allergic rhinitis patients. • Serum activated leukocyte cell adhesion molecule levels were correlated with disease severity of allergic rhinitis. • Serum activated leukocyte cell adhesion molecule can predict efficacy of SLIT in allergic rhinitis. Activated leukocyte cell adhesion molecule (ALCAM) plays an important role in T cell activation and immune response, but the role of ALCAM in allergic rhinitis (AR) remains unclear. The objective of the current study was to validate serum ALCAM as a biomarker in assessing disease severity and predicting the efficacy of sublingual immunotherapy (SLIT) in AR patients. We recruited 40 healthy controls (HC group), 38 mild AR patients (MAR group) and 80 moderate-severe AR patients (MSAR group) in this study. Serum levels of ALCAM were determined by ELISA, and the association between ALCAM levels and disease severity was evaluated. In the MSAR group, 68 patients underwent and finished 3-years of SLIT, and were divided into effective group and ineffective group, the relationship between ALCAM levels and efficacy of SLIT was exampled. ALCAM levels were elevated in the serum of AR patients in comparison with HC. Moreover, serum ALCAM concentrations were higher in MSAR group than in MAR group and HC group, and levels of ALCAM significantly correlated with AR total nasal symptom score (TNSS) (r = 0.330, P < 0.001), visual analogue scale (VAS) (r = 0.387, P < 0.001) and serum total IgE levels (r = 0.442, P < 0.001). In the effective group, the ALCAM levels were significantly lower than in the ineffective group. Receiver operating characteristic (ROC) curve exhibited good accuracy for predicting clinical efficacy of SLIT (area under the curve = 0.805, P < 0.001). The serum ALCAM maybe a novel biomarker for assessing disease severity and predicting clinical efficacy of SLIT in AR patients. [ABSTRACT FROM AUTHOR]

In Streptomyces pristinaespiralis , the orphan histidine kinase (HK) PdtaS-p (encoded by SSDG_02492), which belongs to proteins of two-component systems (TCSs), plays an important role in both morphological differentiation and antibiotic biosynthesis. Owing to the isolated genetic organization of pdtaS-p , it is a challenge to identify its cognate response regulator (RR) and hampers the efforts to elucidate the regulation mechanism of PdtaS-p. In this study, based on bioinformatics analysis, we identify the cognate RR PdtaR-p (encoded by SSDG_04087) of PdtaS-p by phenotype similarity of gene deletion mutants as well as in vitro phosphor-transfer assay. We show that the mutants (Δ pdtaR-p and Δ pdtaS-p) exhibit almost the same phenotypical changes, showing a bald phenotype on MS agar and reduced pristinamycin biosynthesis. Further phosphor-transfer assay indicates that the phosphoryl group of HK PdtaS-p can be specifically transferred to RR PdtaR-p. Compared with the majority of RRs that harbor DNA-binding domains, PdtaR-p contains a putative ANTAR RNA-binding domain involved in controlling gene expression at the post-transcription level. Finally, we demonstrate that their ortholog from the model strain Streptomyces coelicolor , PdtaS-c/PdtaR-c, also regulates both morphological differentiation and antibiotics biosynthesis, suggesting that PdtaS-p/PdtaR-p-mediated molecular regulation may be conserved in the genus Streptomyces. To our knowledge, this is the first report describing the functional identification of ANTAR RNA-binding regulators in Streptomyces. [ABSTRACT FROM AUTHOR]