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Objective: To study the hypoglycemic effect and mechanism of guar gum manno-oligosaccharides (GMOS) on streptozotocin-induced diabetic mice. Methods: GMOS was administered to diabetic mice for 6 weeks, and the changes in body mass and insulin resistance were monitored. Furthermore, indicators of glucose and lipid metabolism such as glucose (GLU), insulin (INS), high density lipoprotein cholesterol (HDL-C), and low density lipoprotein cholesterol (LDL-C) were determined. Hepatic histopathological changes were observed, and the expression of proteins involved in the adenosine monophosphate-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) signaling pathway and the activity of antioxidant enzymes in the liver were detected. Results: GMOS effectively relieved the body mass loss of diabetic mice, significantly alleviated glucose tolerance (30.3%) and enhanced insulin sensitivity (34.6%). Compared with the model group, GMOS decreased the levels of GLU, glycosylated serum protein (GSP) and LDL-C by 38.6%, 29.5%, and 27.3%, respectively, and increased the levels of insulin and HDL-C significantly. Moreover, GMOS reduced oxidative damage, activated the AMPK/PGC-1α signaling pathway, and improved the activities of superoxide dismutase (SOD) and catalase (CAT) in the liver. Conclusion: GMOS could reduce blood glucose and mitigate glucose and lipid metabolism disorder and oxidative stress caused by diabetes mellitus, indicating its potential as a functional food ingredient against diabetes.

Objective: To analyze the clinical features and genetic changes of 3 children in short stature with ACAN gene mutation. Methods: The clinical data, laboratory examinations, and genetic testing results of 3 children with ACAN gene mutations diagnosed with short stature at our pediatric endocrine disease clinic from 2018 to 2020 were collected, and the literature was reviewed for analysis and summary. Results: All the three children had a short family history, and their clinical manifestations were short stature. One patient had a slight limitation of the flexion activity of the thoracolumbar spine, and no other system abnormalities were found. Among them, the oldest of the 3 children was 5 years and 1 month, and the bone age was roughly consistent with or slightly advanced than the actual age, and the peak growth hormone challenge in 2 cases was less than 10 μg/L. The variations in the ACAN gene are c.G1877A and c.7360, respectively_ 7361del and c.7038_ 7039insCGGTGT, case 1 and case 2 are novel mutations that have not been reported in major databases. After the application of recombinant human growth hormone, the height of all three children improved. Reviewing the literature at home and abroad, we found that there were 120 children and 216 relatives reported at present. Among them, there were 80 ACAN gene variants related to short stature registered in HGMD, of which short stature was the most important clinical manifestation, followed by skeletal dysplasia. Conclusions: Mutations of ACAN gene mainly lead to short stature and skeletal dysplasia in children, and their clinical bone phenotypes are diverse, which can also only be manifested as short stature. For children with short stature, especially those with short stature family history, no matter whether they have skeletal abnormalities, they should be alert to this gene mutation.

In this study, beef was marinated with different low-sodium salt substitutes and heated and aged by employing superheated steam roasting and traditional roasting to investigate the effects of the various substitutes on the physicochemical properties, texture profile, sensory properties, volatile compounds, microstructural characteristics, and safety of cured and aged beef. Twenty kilograms of beef were arbitrarily divided into five treatments and pickled with different low-sodium salt substitutes. The results revealed no significant differences in saltiness, physicochemical characteristics, texture profile, or volatile compounds between the T2 and T3 and T1 (100% NaCl, T1; 75% KCl + 25% NaCl, T2; 50% KCl + 50% NaCl, T3) samples. Furthermore, the T4 and T5 (50% NaCl + 25% KCl + 20% MgCl2 + 5% CaCl2, T4; 100% yeast extract, T5) samples had lower saltiness than the T1 sample. The plasmolysis percentage and osmotic pressure of the T2 and T3 samples were lower than those of the T1 sample. Therefore, reducing sodium by substituting NaCl with 50% KCl or 75% KCl maintained an acceptable sensory and safety profile for beef consumption.

Objective: To explore the genotype and clinical phenotype of congenital generalized lipodystrophy type 1(CGL1), and to improve awareness of the disease. Methods: A patient with severe acanthosis nigricans was diagnosed as having CGL1, and the clinical information and results of laboratory and gene tests were analyzed. Five Chinese cases with CGL1 in the database were literaturally reviewed. Results: The patient was a girl(10 years and 11 months), who had significantly acanthosis nigricans and body subcutaneous fat loss. The examination of the girl showed hyperinsulinemia, impaired glucose tolerance, advanced bone age, low adiponectin and polycystic ovary. The compound heterozygous mutations were identified, which was c.646A>T:p.K216*(PVS1_Strong+ PM2+PM3 ( inherited from her father) and c.406G>A:p.G136R(PM3_Strong+PM1+PM2+PP3 (inherited from her mother) in AGPAT2 gene. The mutation of two gene loci could be pathogenic, which had not been reported in CNKI database. All 5 Chinese cases in CNKI database were reported before (including 2 males and 3 females, and age was between 66 days and 26 years old) showed the absence of adipose tissue, in which two patients presented severe acanthosis nigricans. Conclusions: The CGL1 is rare in Chinese population, and it should be considered as the patients present the acanthosis nigricans and absence of adipose tissue, and its diagnosis depends gene detection.

BACKGROUND: Apolygus lucorum, a major cotton pest, has undergone a significant expansion of the FMRFaR gene within the GPCR superfamily, resulting in two classes of GPCR, namely FMRFaR (A54‐55) and newly duplicated FMRFaR‐like (A56‐62). Notably, FMRFaR‐like genes, particularly A62, show enhanced expression in the legs and wings of adults, indicating their potential role in locomotion. Employing A62 as a representative of FMRFaR‐like, our study investigates the influence of FMRFa, FMRFaR, and FMRFaR‐like on locomotion and development of A. lucorum. RESULTS: FMRFaR and FMRFa exhibit comparable temporal and tissue expression patterns, whereas the FMRFaR‐like genes within A. lucorum exhibit completely distinct evolutionary and expression patterns compared to classical FMRFaR. RNA interference (RNAi) experiments revealed that suppressing FMRFa expression results in complete lethality in A. lucorum, but neither FMRFaR nor A62 exhibit the same effect after RNAi. Suppressing the expression of FMRFa only decreases the expression of the A54 gene simultaneously, suggesting that A54 may function as a classical FMRFaR activated by FMRFa. RNAi of A62 leads to wing malformation and a significant reduction in spontaneous movement behavior in A. lucorum. Further transcriptomic analysis revealed that A62 affects the A. lucorum's movement behavior through energy metabolism pathways and motor protein pathways. CONCLUSION: Our study unveils the unique and complex roles of FMRFa and its receptor in A. lucorum. These findings provide valuable insights into potential targets for pest control strategies aimed at managing A. lucorum populations in cotton fields. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Laminaripentaose (L5)‐producing β‐1,3‐glucanases can preferentially cleave the triple‐helix curdlan into β‐1,3‐glucooligosaccharides, especially L5. In this study, a newly identified member of the glycoside hydrolase family 64, β‐1,3‐glucanase from Streptomyces pratensis (SpGlu64A), was functionally and structurally characterized. SpGlu64A shared highest identity (30%) with a β‐1,3‐glucanase from Streptomyces matensis. The purified SpGlu64A showed maximal activity at pH 7.5 and 50 °C, and exhibited strict substrate specificity toward curdlan (83.1 U·mg−1). It efficiently hydrolyzed curdlan to produce L5 as the end product. The overall structure of SpGlu64A consisted of a barrel domain and a mixed (α/β) domain, which formed an unusually wide groove with a crescent‐like structure. In the two complex structures (SpGlu64A–L3 and SpGlu64A–L4), two oligosaccharide chains were captured and the triple‐helical structure was relatively compatible with the wide groove, which suggested the possibility of binding to the triple‐helical β‐1,3‐glucan. A catalytic framework (β6–β9–β10) and the steric hindrance formed by the side chains of residues Y161, N163, and H393 in the catalytic groove were predicted to complete the exotype‐like cleavage manner. On the basis of the structure, a fusion protein with the CBM56 domain (SpGlu64A–CBM) and a mutant (Y161F; by site‐directed mutation) were obtained, with 1.2‐ and 1.7‐fold increases in specific activity, respectively. Moreover, the combined expression of SpGlu64A–CBM and ‐Y161F improved the enzyme activity by 2.63‐fold. The study will not only be helpful in understanding the reaction mechanism of β‐1,3‐glucanases but will also provide a basis for further enzyme engineering. [ABSTRACT FROM AUTHOR]

The development of environment‐friendly bacteriostats in humid atmosphere is designated as a crucial step pointing to sustainable antibiotic‐free alterative. Thanks to the excellent biosafety and intrinsic bacteriostatic attributes, bioactive phytochemical formulations become a fascinating substitute for traditional antibiotics; yet, it remains a challenge to deliver them toward moisture‐activated bacteriostatic application due to the unclear release mechanism and bacteriostatic behavior. Benefitting from "green" metal–organic frameworks (MOFs) evolved from natural γ‐cyclodextrin (γ‐CD) and potassium ion (K+), an intelligent moisture‐activated phytochemical formulation is developed, which is featured by grafting bacteriostatic vanillin (a specific phytochemical extracted from Rutaceae vanilla bean) into microporous structure of MOFs via ligand implantation mechanism. According to the molecular simulation docking, the dominant pattern of host–guest structure is characteristic for H‐bond with a length of 1.9 Å, beneficial for the sterling adsorption capacity. Nevertheless, under moisture exposure, the intermolecular H‐bond is disrupted for vanillin release to destroy bacterial membrane structure, accelerate protein decomposition, and especially inhibit virulence gene transcription of cfa gene in Escherichia coli and sea gene in Staphylococcus aureus, directing to upgrade the insights into the bacteriostatic potency of phytochemicals in high‐humidity circumstance. [ABSTRACT FROM AUTHOR]

As the field of low‐dimensional materials (1D or 2D) grows and more complex and intriguing structures are continuing to be found, there is an emerging need for techniques to characterize the nanoscale mechanical properties of all kinds of 1D/2D materials, in particular in their most practical state: sitting on an underlying substrate. While traditional nanoindentation techniques cannot accurately determine the transverse Young's modulus at the necessary scale without large indentations depths and effects to and from the substrate, herein an atomic‐force‐microscopy‐based modulated nanomechanical measurement technique with Angstrom‐level resolution (MoNI/ÅI) is presented. This technique enables non‐destructive measurements of the out‐of‐plane elasticity of ultra‐thin materials with resolution sufficient to eliminate any contributions from the substrate. This method is used to elucidate the multi‐layer stiffness dependence of graphene deposited via chemical vapor deposition and discover a peak transverse modulus in two‐layer graphene. While MoNI/ÅI has been used toward great findings in the recent past, here all aspects of the implementation of the technique as well as the unique challenges in performing measurements at such small resolutions are encompassed. [ABSTRACT FROM AUTHOR]

The rapidly expanding severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and its variants demand a continuous monitoring method through portable and wearable devices. Utilizing the rich surface chemistry and high chemical‐to‐electrical signal conversion of 2D MXene‐graphene heterostructure thin films, a field‐effect‐transistor (FET) sensor, which has a flexible substrate to be assembled onto the mask and combines with a Bluetooth system for wireless transmission is developed, to detect the influenza and SARS‐CoV‐2 viruses in air and breath. At first, the developed sensors are examined in the laboratory through direct contact with sensing targets in solution form. The results show a low limit of detection (LOD) of 1 fg mL−1 for recombinant SARS‐CoV‐2 spike protein and 125 copies mL−1 for inactivated influenza A (H1N1) virus with high specificity in differing recombinant SARS‐CoV‐2 spike protein and inactivated H1N1 virus. Then the sensors are tested under various simulated human breathing modes through controlled exposure to atomizer‐generated aerosols in an enclosed chamber and mask coverage. The results show the high sensitivity of the developed sensors under varying distances to the source, viral load, flow rate, and enclosed conditions. At last, clinical tests are carried out to demonstrate the robustness and potential field applications of the sensors. [ABSTRACT FROM AUTHOR]

Alpha‐ketoglutarate‐dependent dioxygenase ALKB homologue 4 (ALKBH4) is a member of the Fe (II) and 2‐oxoglutarate‐dependent ALKB homologue family that plays important roles in epigenetic regulation by alkyl lesions removal in mammals. However, the roles of ALKBH4 in insects are not clear. Here, TcALKBH4 was cloned and functionally characterised in Tribolium castaneum. Temporal expression revealed that TcALKBH4 was highly expressed in early embryos and early pupae. Spatial expression showed that TcALKBH4 was highly expressed in the adult testis, and followed by the ovary. RNA interference targeting TcALKBH4 at different developmental stages in T. castaneum led to apparent phenotypes including the failure of development in larvae, the reduction of food intake and the deficiency of fertility in adult. However, further dot blot analyses showed that TcALKBH4 RNAi does not seem to influence 6 mA levels in vivo. qRT‐PCR was used to further explore the underlying molecular mechanisms; the result showed that TcALKBH4 mediates the development of larvae possibly through 20E signalling pathway, and the fertility of female and male adult might be regulated by the expression of vitellogenesis and JH signalling pathway, respectively. Altogether, these findings will provide new insights into the potential function of ALKBH4 in insects. [ABSTRACT FROM AUTHOR]