Dysregulated RNA editing of EIF2AK2 in polycystic ovary syndrome: clinical relevance and functional implications.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder affecting women of reproductive ages. Our previous study has implicated a possible link between RNA editing and PCOS, yet the actual role of RNA editing, its association with clinical features, and the underlying mechanisms remain unclear. METHODS: Ten RNA-Seq datasets containing 269 samples of multiple tissue types, including granulosa cells, T helper cells, placenta, oocyte, endometrial stromal cells, endometrium, and adipose tissues, were retrieved from public databases. Peripheral blood samples were collected from twelve PCOS and ten controls and subjected to RNA-Seq. Transcriptome-wide RNA-Seq data analysis was conducted to identify differential RNA editing (DRE) between PCOS and controls. The functional significance of DRE was evaluated by luciferase reporter assays and overexpression in human HEK293T cells. Dehydroepiandrosterone and lipopolysaccharide were used to stimulate human KGN granulosa cells to evaluate gene expression. RESULTS: RNA editing dysregulations across multiple tissues were found to be associated with PCOS in public datasets. Peripheral blood transcriptome analysis revealed 798 DRE events associated with PCOS. Through weighted gene co-expression network analysis, our results revealed a set of hub DRE events in PCOS blood. A DRE event in the eukaryotic translation initiation factor 2-alpha kinase 2 (EIF2AK2:chr2:37,100,559) was associated with PCOS clinical features such as luteinizing hormone (LH) and the ratio of LH over follicle-stimulating hormone. Luciferase assays, overexpression, and knockout of RNA editing enzyme adenosine deaminase RNA specific (ADAR) showed that the ADAR-mediated editing cis-regulated EIF2AK2 expression. EIAF2AK2 showed a higher expression after dehydroepiandrosterone and lipopolysaccharide stimulation, triggering changes in the downstrean MAPK pathway. CONCLUSIONS: Our study presented the first evidence of cross-tissue RNA editing dysregulation in PCOS and its clinical associations. The dysregulation of RNA editing mediated by ADAR and the disrupted target EIF2AK2 may contribute to PCOS development via the MPAK pathway, underlining such epigenetic mechanisms in the disease.

Monolayer Borophene Formation on Cu(111) Surface Triggered by ⟨ 1 1 ¯ 0 ⟩ $\langle {1\bar{1}0} \rangle $ Step Edge.

Borophene, a promising material with potential applications in electronics, energy storage, and sensors, is successfully grown as a monolayer on Ag(111), Cu(111), and Au(111) surfaces using molecular beam epitaxy. The growth of two-dimensional borophene on Ag(111) and Au(111) is proposed to occur via surface adsorption and boron segregation, respectively. However, the growth mode of borophene on Cu(111) remains unclear. To elucidate this, scanning tunneling microscopy in conjunction with theoretical calculations is used to study the phase transformation of boron nanostructures under post-annealing treatments. Results show that by elevating the substrate temperature, boron nanostructures undergo an evolution from amorphous boron to striped-phase borophene (η = 1/6) adhering to the Cu ⟨ 1 1 ¯ 0 ⟩ $\langle {1\bar{1}0} \rangle $ step edge, and finally to irregularly shaped ß-type borophene (η = 5/36) either on the substrate surface or embedded in the topmost Cu layer. dI/dV spectra recorded near the borophene/Cu lateral interfaces indicate that the striped-phase borophene is a metastable phase, requiring more buckling and electron transfer to stabilize the crystal structure. These findings offer not only an in-depth comprehension of the ß-type borophene formation on Cu(111), but also hold potential for enabling borophene synthesis on weakly-binding semiconducting or insulating substrates with 1D active defects.

An international relations quantitative evaluation model (IRQEM) based on an integrated method.

International relations (IR) have great uncertainty and instability. Bad IR or conflicts will bring about heavy economic losses and widespread social unrest domestically and internationally. The accurate prediction for bilateral relations can support decision making for timely responses, which will be used to find ways to maintain development in the complex international situation. An international relations quantitative evaluation model (IRQEM) is proposed by integrating a variety of research models and methods like the interpretative structural modeling method (ISM), Bayesian network (BN) model, the Bayesian search (BS), and the expectation-maximization (EM) algorithm, which is novel for IR research. Factors from several different fields are identified as BN nodes. Each node is assigned different state values. The hierarchical structure of these BN nodes is obtained by ISM. The data collection of 192 cases is used to construct the BN model by GeNIe 4.0. The IRQEM can be used to evaluate the influence of emergencies on IR. The critical factors of IR also can be explored through our proposed model. Results show that the prediction of bilateral relations under emergencies can be realized by updating the indicator set when emergencies occur. The capability to anticipate threats of IR changes is advanced by optimizing the reporting information of IR forecasting through a combination of qualitative and quantitative methods, charts, and texts. Relevant analysis results can provide support for national security decision making.

Transcriptome analysis reveals the fruit color variation in Ailanthus altissima.

Anthocyanins are responsible for the intensity of color in plants; however, the systematic mechanisms underlying the color differences in the fruit of Ailanthus altissima remain unknown. Therefore, this study aims to analyze the transcriptomes of the white and red fruit of A. altissima by screening and validating the key genes involved in flavonoid and anthocyanin biosynthesis. Samples of A. altissima fruit were collected 30, 45, and 60 days after flowering, and their pigment and sugar content were determined. The anthocyanin content was significantly higher in red than in white fruits. Transcriptome analysis was also performed on the fruit samples, 73,807 unigenes were assembled and annotated to seven databases. Twenty-one co-expressed modules were identified via weighted gene co-expression network analysis, of which two were associated with flavonoids and anthocyanins. Furthermore, in three growth stages, 126, 30, and 124 differentially expressed genes were screened between white and red fruit. Genes involved in flavonoid and anthocyanin metabolism were identified. AaDFR (A. altissima bifunctional dihydroflavonol 4-reductase/flavanone 4-reductase) and AaANS (A. altissima anthocyanidin synthase) were associated with flavonoid and anthocyanin metabolism. Members of the AaDFR and AaANS families were also identified, and their basic physicochemical characteristics, conserved domains, motif compositions, phylogenetics, and expression levels were analyzed. The overexpression of AaDFR and AaANS in transgenic Arabidopsis significantly increased the content of seed and foliar flavonoids and anthocyanins. The study elucidated the different mechanisms underlying fruit color development and provided insight into A. altissima plants breeding with commercially desirable properties.

Impacts of Ship Emissions on Air Quality in Southern China: Opportunistic Insights from the Abrupt Emission Changes in Early 2020.

In early 2020, two unique events perturbed ship emissions of pollutants around Southern China, proffering insights into the impacts of ship emissions on regional air quality: the decline of ship activities due to COVID-19 and the global enforcement of low-sulfur (<0.5%) fuel oil for ships. In January and February 2020, estimated ship emissions of NOx, SO2, and primary PM2.5 over Southern China dropped by 19, 71, and 58%, respectively, relative to the same period in 2019. The decline of ship NOx emissions was mostly over the coastal waters and inland waterways of Southern China due to reduced ship activities. The decline of ship SO2 and primary PM2.5 emissions was most pronounced outside the Chinese Domestic Emission Control Area due to the switch to low-sulfur fuel oil there. Ship emission reductions in early 2020 drove 16 to 18% decreases in surface NO2 levels but 3.8 to 4.9% increases in surface ozone over Southern China. We estimated that ship emissions contributed 40% of surface NO2 concentrations over Guangdong in winter. Our results indicated that future abatements of ship emissions should be implemented synergistically with reductions of land-borne anthropogenic emissions of nonmethane volatile organic compounds to effectively alleviate regional ozone pollution.

Human Umbilical Vein Endothelial Cells Survive on the Ischemic TCA Cycle under Lethal Ischemic Conditions.

It is generally believed that vascular endothelial cells (VECs) rely on glycolysis instead of the tricarboxylic acid (TCA) cycle under both normoxic and hypoxic conditions. However, the metabolic pattern of human umbilical vein endothelial cells (HUVECs) under extreme ischemia (hypoxia and nutrient deprivation) needs to be elucidated. We initiated a lethal ischemic model of HUVECs, performed proteomics and bioinformatics, and verified the metabolic pattern shift of HUVECs. Ischemic HUVECs displayed extensive aerobic respiration, including upregulation of the TCA cycle and mitochondrial respiratory chain in mitochondria and downregulation of glycolysis in cytoplasm. The TCA cycle was enhanced while the cell viability was decreased through the citrate synthase pathway when substrates of the TCA cycle (acetate and/or pyruvate) were added and vice versa when inhibitors of the TCA cycle (palmitoyl-CoA and/or avidin) were applied. The inconsistency of the TCA cycle level and cell viability suggested that the extensive TCA cycle can keep cells alive yet generate toxic substances that reduce cell viability. The data revealed that HUVECs depend on "ischemic TCA cycle" instead of glycolysis to keep cells alive under lethal ischemic conditions, but consideration must be given to relieve cell injury.

Genome-wide identification of BAM (ß-amylase) gene family in jujube (Ziziphus jujuba Mill.) and expression in response to abiotic stress.

BACKGROUND: Elevated temperature and drought stress have substantial impacts on fruit quality, especially in terms of sugar metabolism and content. ß-Amylase (BAM) plays a critical role in regulating jujube fruit sugar levels and abiotic stress response. Nevertheless, little is known about the regulatory functions of the BAM genes in jujube fruit. RESULTS: Nine jujube BAM genes were identified, clustered into four groups, and characterized to elucidate their structure, function, and distribution. Multiple sequence alignment and gene structure analysis showed that all ZjBAM genes contain Glu-186 and Glu-380 residues and are highly conserved. Phylogenetic and synteny analysis further indicated that the ZjBAM gene family is evolutionarily conserved and formed collinear pairs with the BAM genes of peach, apple, poplar, Arabidopsis thaliana, and cucumber. A single tandem gene pair was found within the ZjBAM gene family and is indicative of putative gene duplication events. We also explored the physicochemical properties, conserved motifs, and chromosomal and subcellular localization of ZjBAM genes as well as the interaction networks and 3D structures of ZjBAM proteins. A promoter cis-acting element analysis suggested that ZjBAM promoters comprise elements related to growth, development, phytohormones, and stress response. Furthermore, a metabolic pathways annotation analysis showed that ZjBAMs are significantly upregulated in the starch and sucrose metabolism, thereby controlling starch-maltose interconversion and hydrolyzing starch to maltose. Transcriptome and qRT-PCR analyses revealed that ZjBAMs respond positively to elevated temperature and drought stress. Specifically, ZjBAM1, ZjBAM2, ZjBAM5, and ZjBAM6 are significantly upregulated in response to severe drought. Bimolecular fluorescence complementation analysis demonstrated ZjBAM1-ZjAMY3, ZjBAM8-ZjDPE1, and ZjBAM7-ZjDPE1 protein interactions that were mainly present in the plasma membrane and nucleus. CONCLUSION: The jujube BAM gene family exhibits high evolutionary conservation. The various expression patterns of ZjBAM gene family members indicate that they play key roles in jujube growth, development, and abiotic stress response. Additionally, ZjBAMs interact with α-amylase and glucanotransferase. Collectively, the present study provides novel insights into the structure, evolution, and functions of the jujube BAM gene family, thus laying a foundation for further exploration of ZjBAM functional mechanisms in response to elevated temperature and drought stress, while opening up avenues for the development of economic forests in arid areas.

Urine Gonadotropin Measurement in Laboratory for Evaluating the Function of HPGA in Girls.

BACKGROUND: The evaluation of hypothalamic-pituitary-gonadal axis function is essential for girls with pubertal disorders. The laboratory gold standard for evaluating the axis is blood gonadotropin level during gonadotropin-releasing hormone stimulation test. However, these tests need venipuncture and repeated blood collection, which affect the compliance of children and parents. METHODS: Studies were conducted on the basis of a computer-assisted search of the literature published in English using the National Library of Medicine, PubMed, Google Scholar, and Google databases, and published in Chinese core journals. RESULTS: According to this review, urine collection is non-invasive and convenient. Urine gonadotropin can reflect the average level of blood, which can reflect the HPGA function of girls with pubertal disorders. However, because of the limited sensitivity of LH detection, urine Gn during the GnRH stimulation test cannot replace that of the blood. CONCLUSIONS: It is worth improving the sensitivity of LH detection kits. In the future, perhaps most exciting is replacing blood for evaluating HPGA function in girls with the urine Gn determination in the lab during the GnRH stimulation test.

A single blood sample for stimulated LH assayed by ICMA is useful for monitoring the treatment efficacy of triptorelin depot in girls.

BACKGROUND: There is still no consensus on the optimal monitoring method to evaluate the hypothalamic-pituitary-gonadal axis (HPGA) inhibition. METHODS: There were 124 girls treated with triptorelin depot due to puberty disorders, including 77 central precocious puberty and 47 early puberty. After treatment, triptorelin stimulation tests were performed, and blood samples were collected at 0, 20, 40 and 60 min. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured by immunochemiluminometric assay (ICMA). RESULTS: Peak LH (PLH), peak FSH and estradiol in 124 girls were significantly decreased after treatment, while 2 cases had inadequate treatment efficacy. Areas under the receiver operating characteristic curves (AUC) of PLH and peak FSH after stimulation for the diagnosis of HPGA suppression were 0.984 and 0.121. When the cut-off value of PLH was ≤ 2.25 IU/L, the sensitivity was 96.7% and specificity was 100.0%. There was no difference in AUC between PLH and a single LH at 20, 40, or 60 min (p > 0.05). When LH were ≤ 2.34 IU/L, ≤ 2.21 IU/L and ≤ 2.00 IU/L at 20, 40 and 60 min, respectively, the sensitivity were 99.1%, 96.7% and 98.4%, and the specificity were all 100.0%. The correlation coefficients between PLH and LH at 20, 40 or 60 min were 0.947, 0.975 and 0.961. CONCLUSION: A single blood sample for stimulated LH at 20 min, 40 min, or 60 min assayed by ICMA during triptorelin stimulation test is useful for monitoring the treatment efficacy of triptorelin depot in girls with puberty disorders.

Adult height in pubertal boys with short stature treated with GH/letrozole: a hospital record-based retrospective study.

BACKGROUND: The growth potential in pubertal boys with short stature is limited by the effect of estrogen on epiphyseal fusion. This study aims to identify the efficacy and safety of the combination of growth hormone (GH) and letrozole on adult height (AH) in pubertal boys with short stature. METHODS: This is a retrospective record based study. Pubertal boys with short stature who were treated with GH and letrozole were followed up at outpatient clinics in our hospital. Twenty subjects who reached AH are reported here. RESULTS: Baseline chronological age was 12.12 ± 1.14 yr and bone age was 13.00 ± 0.93 yr. The period of GH/letrozole treatment was 1.94 ± 0.67 yr. Height standard deviation score for bone age was increased from -1.46 ± 0.51 before treatment to -0.12 ± 0.57 after treatment (P < 0.001). The predicted AH before treatment, predicted AH after treatment, AH, and genetic target height were 161.02 ± 4.12 cm, 172.11 ± 4.20 cm, 172.67 ± 2.72 cm, and 167.67 ± 3.56 cm, respectively. There was a significant predicted AH difference before and after treatment (P < 0.001). There was a significant difference between predicted AH before treatment and genetic target height (P < 0.001). Predicted AH after therapy was higher than that of gene target height (P < 0.001), as well as AH and genetic target height (P < 0.001). There was no significant side effect. CONCLUSIONS: GH and letrozole combination can enhance AH in pubertal boys with short stature.

Recent Advances in Surface Modifications of Elemental Two-Dimensional Materials: Structures, Properties, and Applications.

The advent of graphene opens up the research into two-dimensional (2D) materials, which are considered revolutionary materials. Due to its unique geometric structure, graphene exhibits a series of exotic physical and chemical properties. In addition, single-element-based 2D materials (Xenes) have garnered tremendous interest. At present, 16 kinds of Xenes (silicene, borophene, germanene, phosphorene, tellurene, etc.) have been explored, mainly distributed in the third, fourth, fifth, and sixth main groups. The current methods to prepare monolayers or few-layer 2D materials include epitaxy growth, mechanical exfoliation, and liquid phase exfoliation. Although two Xenes (aluminene and indiene) have not been synthesized due to the limitations of synthetic methods and the stability of Xenes, other Xenes have been successfully created via elaborate artificial design and synthesis. Focusing on elemental 2D materials, this review mainly summarizes the recently reported work about tuning the electronic, optical, mechanical, and chemical properties of Xenes via surface modifications, achieved using controllable approaches (doping, adsorption, strain, intercalation, phase transition, etc.) to broaden their applications in various fields, including spintronics, electronics, optoelectronics, superconducting, photovoltaics, sensors, catalysis, and biomedicines. These advances in the surface modification of Xenes have laid a theoretical and experimental foundation for the development of 2D materials and their practical applications in diverse fields.

Novel compound heterozygous mutations of PCNT gene in MOPD type II with central precocious puberty.

We report on a 6-year and 11-month old girl with short stature, microcephaly, proboscis nose, small teeth, left breast Tanner stage II, and nasopharynx adenoid hypertrophy. Her gestational age was 37 weeks and birth weight was 800 g. Her growth hormone peak was higher than 35.2 ng/ml, luteinizing hormone peak 8.97 IU/l, and blood glucose of 120 min 7.82 mmol/l in oral glucose tolerance test. Genetic testing revealed two novel heterozygous mutations in the PCNT gene, an insertion mutation at c.1828dupT (p.S610Ffs*32), and a splice site mutation at c.1207 + 1G>A, which were inherited from healthy carrier patients. This case shows that MOPDII can be associated with central precocious puberty and impaired glucose tolerance in addition to intrauterine growth restriction, postpartum growth defect, and microcephaly.

Significant Changes in Chemistry of Fine Particles in Wintertime Beijing from 2007 to 2017: Impact of Clean Air Actions.

The Beijing government implemented a number of clean air action plans to improve air quality in the last 10 years, which contributed to changes in the concentration of fine particles and their compositions. However, quantifying the impacts of these interventions is challenging as meteorology masks the real changes in observed concentrations. Here, we applied a machine learning technique to decouple the effect of meteorology and evaluate the changes in the chemistry of nonrefractory PM1 (particulate matter less than 1 µm) in winter 2007, 2016, and 2017 as a result of the clean air actions. The observed mass concentrations of PM1 were 74.6, 90.2, and 36.1 µg m-3 in the three winters, while the deweathered concentrations were 74.2, 78.7, and 46.3 µg m-3, respectively. The deweathered concentrations of PM1, organics, sulfate, ammonium, chloride, SO2, NO2, and CO decreased by -38, -46, -59, -24, -51, -89, -16, and -52% in 2017 in comparison to 2007. On the contrary, the deweathered concentration of nitrates increased by 4%. Our results indicate that the clean air actions implemented in 2017 were highly effective in reducing ambient concentrations of SO2, CO, and PM1 organics, sulfate, ammonium, and chloride, but the control of nitrate and PM1 organics remains a major challenge.

Whole-Genome Sequencing of African Dogs Provides Insights into Adaptations against Tropical Parasites.

Natural selection in domestic dogs is of great interest in evolutionary biology since dogs have migrated to every inhabited continent of the world alongside humans, and adapted to diverse environments. Here, we explored their demographic history and genetic basis of adaptation to the tropical African environment using whole genome analyses of 19 African indigenous dogs from Nigeria. Demographic analysis suggests that the ancestors of these dogs migrated into Africa from Eurasia 14,000 years ago and underwent a severe founder effect before population expansion. Admixture analysis further reveals that African dog genomes contain about 1.88-3.50% introgression from African golden wolves (Canis anthus). Population genetic analysis identifies 50 positively selected genes linked with immunity, angiogenesis, ultraviolet protection, as well as insulin secretion and sensitivity that may contribute to adaptation to tropical conditions. One of the positively selected genes, adhesion G protein-coupled receptor E1 (ADGRE1), has also been found to be association with severe malaria resistance in African human populations. Functional assessments showed that ADGRE1 provides protective host defense against Plasmodium infections. This result, together with the fact that the inflammatory response to canine babesiosis is similar to complicated falciparum malaria in humans, support the dogs as a model for the study of malaria control and treatment.

Effects of Storage Conditions on Urinary LH and FSH Measurement Using Immunochemiluminometric Assay.

BACKGROUND: Urine is a good alternative body fluid for gonadotropin studies. There was limited information about the effects of different storage conditions on urinary gonadotropin measurement by using immunochemiluminometric assay (ICMA). METHODS: ICMA was used to determine gonadotropin in urine stored under different conditions, such as different pH, storage time, and cycles of freeze-thaw. RESULTS: Luteinizing hormone (LH) level was not significantly affected at pH 2.5 to 10.5 or being stored at 4°C for 3 days. Follicular stimulating hormone (FSH) level was not significantly changed at pH 3.5 to 10.5 or throughout 49-day storage at 4°C in the absence of glycerol. LH was significantly decreased after freeze-thawing twice, while FSH was resistant to freeze-thaw procedures. CONCLUSIONS: LH and FSH can be determined by ICMA in normal urine pH range (4.6 ~ 8.0). Urine LH is more sensitive to long-term storage and multiple freeze-thaw procedures than FSH.

The Dynamic Trends of Urinary LH and FSH Assayed by ICMA During Triptorelin Stimulation Tests in Girls - a Pilot Study.

BACKGROUND: Gonadotropin-releasing hormone stimulation test is a gold standard for evaluating the function of the hypothalamic-pituitary-gonadal axis (HPGA) in children. These tests are usually uncomfortable because of multi-venipunctures. A urine specimen is a good alternative because it is noninvasive and convenient. More studies have shown the correlation between sera and urine LH and FSH levels under different physiological and pathological conditions. METHODS: The study investigated the dynamic trends of urine LH (uLH) and FSH (uFSH) assayed by immunochemiluminometric assays (ICMA) during triptorelin stimulation tests in girls. The triptorelin stimulation tests were performed in 52 girls with disorders of puberty. The time 0 hour was regarded as the start time of the test (8:30 am). The day before the tests, urine samples were collected at 12 hours diurnal (-24 hours ~ -12 hours) and nocturnal (-12 hours ~ 0 hour) time points. On the day of the testing, the first 12 hours (0 hour ~ 12 hours), the second 12 hours (12 hours ~ 24 hours), the third 12 hours (24 hours ~ 36 hours), the fourth 12 hours (36 hours ~ 48 hours), the third and fourth overnight urine samples were also collected. The LH and FSH levels were assayed by ICMA, and uLH and uFSH were corrected for creatinine (Cr). RESULTS: The HPGA in 41 girls was activated but it was nonactivated in 11 girls. In girls with HPGA activated, uLH/Cr or uFSH/Cr was significantly elevated within 24 hours, and gradually dropped to baseline after 48 hours. When HPGA was nonactivated in girls, there were the same dynamic trends but much lower amplitude of uLH/Cr or uFSH/Cr, which dropped to baseline after 24 hours. CONCLUSIONS: The stimulated uLH and uFSH assayed by ICMA are valuable for evaluating the function of HPGA in girls, and the valuable time window is within 24 hours.

The origin of chow chows in the light of the East Asian breeds.

BACKGROUND: East Asian dog breeds are one of the most ancient groups of dogs that radiated after the domestication of the dog and represent the most basal lineages of dog evolution. Among these, the Chow Chow is an ancient breed that embodies very distinct morphological and physiological features, such as sturdy build, dense coat, and blue/purple tongue. RESULTS: Using a Restricted site Associated DNA (RAD) sequencing approach, we sequenced the genomes of nine Chow Chows from China. Combined with a dataset of 37 canid whole genome sequencing (WGS) from several published works, we found that the Chow Chow is one of the most basal lineages, which originated together with other East Asian breeds, such as the Shar-Pei and Akita. Demographic analysis found that Chow Chows originated from the Chinese indigenous dog about 8300 years ago. The bottleneck leading to Chow Chows was not strong and genetic migration between Chow Chows and other populations is low. Two classes of genes show strong evidence of positive selection along the Chow Chow lineage, namely genes related to metabolism and digestion as well as muscle/heart development and differentiation. CONCLUSIONS: Dog breeds from East Asia, including the Chow Chow, originated from Chinese indigenous dogs very early in time. The genetic bottleneck leading to Chow Chows and migrations with other populations are found to be quite mild. Our current study represents an early endeavor to characterize the origin of East Asian dog breeds and establishes an important reference point for understanding the origin of ancient breeds in Asia.

Effect of High-Pressure Treatment on Catalytic and Physicochemical Properties of Pepsin.

For a long time, high-pressure treatment has been used to destroy the compact structures of natural proteins in order to promote subsequent enzymatic hydrolysis. However, there are few reports evaluating the feasibility of directly improving the catalytic capability of proteases by using high-pressure treatments. In this study, the effects of high-pressure treatment on the catalytic capacity and structure of pepsin were investigated, and the relationship between its catalytic properties and changes in its physicochemical properties was explored. It was found that high-pressure treatment could lead to changes of the sulfhydryl group/disulfide bond content, hydrophobicity, hydrodynamic radius, intrinsic viscosity, and subunit composition of pepsin, and the conformational change of pepsin resulted in improvement to its enzymatic activity and hydrolysis efficiency, which had an obvious relationship with the high-pressure treatment conditions.

[Effects of intragastric administration of formaldehyde on superoxide dismutase activities and malondialdehyde contents in liver of mice].

OBJECTIVE: To study the effects of intragastric administration of formaldehyde on lipid peroxidation in mice. METHODS: Thirty ICR mice were randomly divided into 3 groups: one control group and two experimental groups. The mice were given formaldehyde (the dose is 0, 5 and 20 mg/kg body weight respectively) through intragastric administration once a day for 5 days , and then they were killed. The activities of SOD and the contents of MDA in liver were measured. RESULTS: The activities of SOD in the 20 mg/kg body weight group were significantly lower than the control group (P < 0.05), and the contents of MDA in the 20 mg/kg body weight group were significantly higher than the control group (P < 0.05), and the liver organ coefficient in the 20 mg/kg body weight group is higher than the control group (P < 0.05). CONCLUSION: A certain dose of formaldehyde can destroy the balance of lipid peroxidation in mice, the ability of antioxidation is reduced obviously, and the liver become compensatory hypertrophy.

Correction: Development of bioactive and ultrasound-responsive microdroplets for preventing ovariectomy (OVX)-induced osteoporosis.

Correction for 'Development of bioactive and ultrasound-responsive microdroplets for preventing ovariectomy (OVX)-induced osteoporosis' by Yi Zhang et al., J. Mater. Chem. B, 2023, 11, 11344-11356, https://doi.org/10.1039/D3TB01726E.