Clock-dependent chromatin accessibility rhythms regulate circadian transcription.

Chromatin organization plays a crucial role in gene regulation by controlling the accessibility of DNA to transcription machinery. While significant progress has been made in understanding the regulatory role of clock proteins in circadian rhythms, how chromatin organization affects circadian rhythms remains poorly understood. Here, we employed ATAC-seq (Assay for Transposase-Accessible Chromatin with Sequencing) on FAC-sorted Drosophila clock neurons to assess genome-wide chromatin accessibility at dawn and dusk over the circadian cycle. We observed significant oscillations in chromatin accessibility at promoter and enhancer regions of hundreds of genes, with enhanced accessibility either at dusk or dawn, which correlated with their peak transcriptional activity. Notably, genes with enhanced accessibility at dusk were enriched with E-box motifs, while those more accessible at dawn were enriched with VRI/PDP1-box motifs, indicating that they are regulated by the core circadian feedback loops, PER/CLK and VRI/PDP1, respectively. Further, we observed a complete loss of chromatin accessibility rhythms in per01 null mutants, with chromatin consistently accessible at both dawn and dusk, underscoring the critical role of Period protein in driving chromatin compaction during the repression phase at dawn. Together, this study demonstrates the significant role of chromatin organization in circadian regulation, revealing how the interplay between clock proteins and chromatin structure orchestrates the precise timing of biological processes throughout the day. This work further implies that variations in chromatin accessibility might play a central role in the generation of diverse circadian gene expression patterns in clock neurons.

FOSL1 modulates Schwann cell responses in the wound microenvironment and regulates peripheral nerve regeneration.

Peripheral glial Schwann cells switch to a repair state after nerve injury, proliferate to supply lost cell population, migrate to form regeneration tracks, and contribute to the generation of a permissive microenvironment for nerve regeneration. Exploring essential regulators of the repair responses of Schwann cells may benefit the clinical treatment for peripheral nerve injury. In the present study, we find that FOSL1, a AP-1 member that encodes transcription factor FOS Like 1, is highly expressed at the injured sites following peripheral nerve crush. Interfering FOSL1 decreases the proliferation rate and migration ability of Schwann cells, leading to impaired nerve regeneration. Mechanism investigations demonstrate that FOSL1 regulates Schwann cell proliferation and migration by directly binding to the promoter of EPH Receptor B2 (EPHB2) and promoting EPHB2 transcription. Collectively, our findings reveal the essential roles of FOSL1 in regulating the activation of Schwann cells and indicate that FOSL1 can be targeted as a novel therapeutic approach to orchestrate the regeneration and functional recovery of injured peripheral nerves.

Downregulation of tRF-Cys-GCA-029 by hyperglycemia promotes tumorigenesis and glycolysis of diabetic breast cancer through upregulating PRKCG translation.

BACKGROUND: Diabetes mellitus (DM) affects up to one-third of breast cancer (BC) patients. Patients with co-existing BC and DM (BC-DM) have worsened BC prognosis. Nevertheless, the molecular mechanisms orchestrating BC-DM prognosis remain poorly understood. tRNA-derived fragments (tRFs) have been shown to regulate cancer progression. However, the biological role of tRFs in BC-DM has not been explored. METHODS: tRF levels in tumor tissues and cells were detected by tRF sequencing and qRT-PCR. The effects of tRF on BC cell malignancy were assessed under euglycemic and hyperglycemic conditions in vitro. Metabolic changes were assessed by lactate, pyruvate, and extracellular acidification rate (ECAR) assays. Diabetic animal model was used to evaluate the impacts of tRF on BC tumor growth. RNA-sequencing (RNA-seq), qRT-PCR, Western blot, polysome profiling, luciferase reporter assay, and rescue experiments were performed to explore the regulatory mechanisms of tRF in BC-DM. RESULTS: We identified that tRF-Cys-GCA-029 was downregulated in BC-DM tissues and under hyperglycemia conditions in BC cells. Functionally, downregulation of tRF-Cys-GCA-029 promoted BC cell proliferation and migration in a glucose level-dependent manner. tRF-Cys-GCA-029 knockdown also enhanced glycolysis metabolism in BC cells, indicated by increasing lactate/pyruvate production and ECAR levels. Notably, injection of tRF-Cys-GCA-029 mimic significantly suppressed BC tumor growth in diabetic-mice. Mechanistically, tRF-Cys-GCA-029 regulated BC cell malignancy and glycolysis via interacting with PRKCG in two ways: binding to the coding sequence (CDS) of PRKCG mRNA to regulate its transcription and altering polysomal PRKCG mRNA expression to modify its translation. CONCLUSIONS: Hyperglycemia-downregulated tRF-Cys-GCA-029 enhances the malignancy and glycolysis of BC cells. tRF-Cys-GCA-029-PRKCG-glycolysis axis may be a potential therapeutic target against BC-DM.

Single-cell transcriptomics analysis of cellular heterogeneity and immune mechanisms in neurodegenerative diseases.

Single-cell transcriptomics analysis is an advanced technology that can describe the intracellular transcriptome in complex tissues. It profiles and analyses datasets by single-cell RNA sequencing. Neurodegenerative diseases are identified by the abnormal apoptosis of neurons in the brain with few or no effective therapy strategies at present, which has been a growing healthcare concern and brought a great burden to society. The transcriptome of individual cells provides deep insights into previously unforeseen cellular heterogeneity and gene expression differences in neurodegenerative disorders. It detects multiple cell subsets and functional changes during pathological progression, which deepens the understanding of the molecular underpinnings and cellular basis of neurodegenerative diseases. Furthermore, the transcriptome analysis of immune cells shows the regulation of immune response. Different subtypes of immune cells and their interaction are found to contribute to disease progression. This finding enables the discovery of novel targets and biomarkers for early diagnosis. In this review, we emphasize the principles of the technology, and its recent progress in the study of cellular heterogeneity and immune mechanisms in neurodegenerative diseases. The application of single-cell transcriptomics analysis in neurodegenerative disorders would help explore the pathogenesis of these diseases and develop novel therapeutic methods.

Bioinspired Dual Hemin-Bonded G-Quadruplex and Histidine-Functionalized Metal-Organic Framework for Sensitive Biosensing.

Biomimetic enzymes have emerged as ideal alternatives to natural enzymes, and there is considerable interest in designing biomimetic enzymes with enhanced catalytic performance to address the low activity of the current biomimetic enzymes. In this study, we proposed a meaningful strategy for constructing an efficient peroxidase-mimicking catalyst, called HhG-MOF, by anchoring histidine (H) and dual hemin-G-quadruplex DNAzyme (double hemin covalently linked to 3' and 5' terminals of G-quadruplex DNA, short as hG) to a mesoporous metal-organic framework (MOF). This design aims to mimic the microenvironment of natural peroxidase. Remarkably, taking a terbium MOF as a typical model, the initial rate of the resulting catalyst was found to be 21.1 and 4.3 times higher than that of Hh-MOF and hG-MOF, respectively. The exceptional catalytic properties of HhG-MOF can be attributed to its strong affinity for substrates. Based on the inhibitory effect of thiocholine (TCh) produced by the reaction between acetylcholinesterase (AChE) and acetylthiocholine, a facile, cost-effective, and sensitive colorimetric method was designed based on HhG-MOF for the measurement of AChE, a marker of several neurological diseases, and its inhibitor. This allowed a linear response in the 0.002 to 1 U L-1 range, with a detection limit of 0.001 U L-1. Furthermore, the prepared sensor demonstrated great selectivity and performed well in real blood samples, suggesting that it holds promise for applications in the clinical field.

Systemic loss of CD36 aggravates NAFLD-related HCC through MEK1/2-ERK1/2 signaling pathway.

BACKGROUND & AIMS: CD36, a membrane protein widely present in various tissues, is crucial role in regulating energy metabolism. The rise of HCC as a notable outcome of NAFLD is becoming more apparent. Patients with hereditary CD36 deficiency are at increased risk of NAFLD. However, the impact of CD36 deficiency on NAFLD-HCC remains unclear. METHODS: Global CD36 knockout mice (CD36KO) and wild type mice (WT) were induced to establish NAFLD-HCC model by N-nitrosodiethylamine (DEN) plus high fat diet (HFD). Transcriptomics was employed to examine genes that were expressed differentially. RESULTS: Compared to WT mice, CD36KO mice showed more severe HFD-induced liver issues and increased tumor malignancy. The MEK1/2-ERK1/2 pathway activation was detected in the liver tissues of CD36KO mice using RNA sequencing and Western blot analysis. CONCLUSION: Systemic loss of CD36 leaded to the advancement of NAFLD to HCC by causing lipid disorders and metabolic inflammation, a process that involves the activation of MAPK signaling pathway. We found that CD36 contributes significantly to the maintenance of metabolic homeostasis in NAFLD-HCC.

The role of the cytochrome P450 superfamily in the skin.

In mammals, the skin acts as a barrier to prevent harmful environmental stimuli from entering the circulation. CYP450s are involved in drug biotransformation, exogenous and endogenous substrate metabolism, and maintaining the normal physiological function of the skin, as well as facilitating homeostasis of the internal environment. The expression pattern of CYP450s in the skin is tissue-specific and thus differs from the liver and other organs. The development of skin topical medications, and knowledge of the toxicity and side effects of these medications require a detailed understanding of the expression and function of skin-specific CYP450s. Thus, we summarized the expression of CYP450s in the skin, their function in endogenous metabolic physiology, aberrant CYP450 expression in skin diseases and the influence of environmental variables and medications. This information will serve as a crucial foundation for future studies on the skin, as well as for the design and development of new drugs for skin diseases including topical medications.

Largely Improving the Output Performance of Stretchable Triboelectric Nanogenerators via Thermo-Compressive Technology.

Stretchable triboelectric nanogenerators (TENGs) are widely applied in wearable and implantable electronics, smart medical devices, and soft robots. However, it is still a challenge to produce stretchable TENGs with both exceptional elasticity and output performance, which limits their application scope. In this work, high-performance stretchable TENGs are developed through a thermo-compression (TC) fabrication process. In particular, a poly(vinylidene fluoride) film is compactly bound to the elastic thermoplastic polyurethane substrate, which inherits excellent stretchability with a strain of up to 815%. Furthermore, owing to the large surface area, tight contact, and effective vertical transport of tribo-induced charges between the coupled fibrous tribo-layer and soft substrate, the TC composite film-based TENGs exhibit a greater output (2-4 times) than unlaminated film-based TENGs. Additionally, the broad universality of this method is proven using various tribo- and substrate materials. The proposed technology provides a novel and effective approach to conjointly boost the output and stretchability of TENGs, showing encouraging application prospects in self-powered wearable and flexible electronics.

Bacillus suppresses nitrogen efficiency of soybean-rhizobium symbiosis through regulation of nitrogen-related transcriptional and microbial patterns.

The regulation of legume-rhizobia symbiosis by microorganisms has obtained considerable interest in recent research, particularly in the common rhizobacteria Bacillus. However, few studies have provided detailed explanations regarding the regulatory mechanisms involved. Here, we investigated the effects of Bacillus (Bac.B) on Bradyrhizobium-soybean (Glycine max) symbiosis and elucidated the underlying ecological mechanisms. We found that two Bradyrhizobium strains (i.e. Bra.Q2 and Bra.D) isolated from nodules significantly promoted nitrogen (N) efficiency of soybean via facilitating nodule formation, thereby enhanced plant growth and yield. However, the intrusion of Bac.B caused a reverse shift in the synergistic efficiency of N2 fixation in the soybean-Bradyrhizobium symbiosis. Biofilm formation and naringenin may be importantin suppression of Bra.Q2 growth regulated by Bac.B. In addition, transcriptome and microbiome analyses revealed that Bra.Q2 and Bac.B might interact to regulateN transport and assimilation, thus influence the bacterial composition related to plant N nutrition in nodules. Also, the metabolisms of secondary metabolites and hormones associated with plant-microbe interaction and growth regulation were modulated by Bra.Q2 and Bac.B coinoculation. Collectively, we demonstrate that Bacillus negatively affects Bradyrhizobium-soybean symbiosis and modulate microbial interactions in the nodule. Our findings highlight a novel Bacillus-based regulation to improve N efficiency and sustainable agricultural development.

Comparative safety assessment of nasogastric versus nasojejunal feeding initiated within 48 hours post-admission versus unrestricted timing in moderate or severe acute pancreatitis: a systematic review and meta-analysis.

BACKGROUND: The primary objective of this study is to comparatively assess the safety of nasogastric (NG) feeding versus nasojejunal (NJ) feeding in patients with acute pancreatitis (AP), with a special focus on the initiation of these feeding methods within the first 48 h of hospital admission. METHODS: Studies were identified through a systematic search in PubMed, EMbase, Cochrane Central Register of Controlled Trials, and Web of Science. Four studies involving 217 patients were included. This systematic review assesses the safety and efficacy of nasogastric versus nasojejunal feeding initiated within 48 h post-admission in moderate/severe acute pancreatitis, with a specific focus on the timing of initiation and patient age as influential factors. RESULTS: The results showed that the mortality rates were similar between NG and NJ feeding groups (RR 0.86, 95% CI 0.42 to 1.77, P = 0.68). Significant differences were observed in the incidence of diarrhea (RR 2.75, 95% CI 1.21 to 6.25, P = 0.02) and pain (RR 2.91, 95% CI 1.50 to 5.64, P = 0.002) in the NG group. The NG group also showed a higher probability of infection (6.67% vs. 3.33%, P = 0.027) and a higher frequency of multiple organ failures. Subgroup analysis for early intervention (within 48 h) showed a higher risk of diarrhea in the NG group (RR 2.80, P = 0.02). No significant differences were found in the need for surgical intervention, parenteral nutrition, or success rates of feeding procedures. CONCLUSION: This meta-analysis highlights the importance of considering the method and timing of nutritional support in acute pancreatitis. While NG feeding within 48 h of admission increases the risk of certain complications such as diarrhea and infection, it does not significantly impact mortality or the need for surgical intervention.

Understanding the mechanistic roles of microplastics combined with heavy metals in regulating ferroptosis: Adding new paradigms regarding the links with diseases.

As a new type of pollutant, microplastics (MPs) commonly exist in today's ecosystems, causing damage to the ecological environment and the health of biological organisms, including human beings. MPs can function as carriers of heavy metals (HMs) to aggravate the enrichment of HMs in important organs of organisms, posing a great threat to health. Ferroptosis, a novel process for the regulation of nonapoptotic cell death, has been shown to be closely related to the occurrence and processes of MPs and HMs in diseases. In recent years, some HMs, such as cadmium (Cd), iron (Fe), arsenic (As) and copper (Cu), have been proven to induce ferroptosis. MPs can function as carriers of HMs to aggravate damage to the body. This damage involves oxidative stress, mitochondrial dysfunction, lipid peroxidation (LPO), inflammation, endoplasmic reticulum stress (ERS) and so on. Therefore, ferroptosis has great potential as a therapeutic target for diseases induced by MPs combined with HMs. This paper systematically reviews the potential effects and regulatory mechanisms of MPs and HMs in the process of ferroptosis, focusing on the mitochondrial damage, Fe accumulation, LPO, ERS and inflammation caused by MPs and HMs that affect the regulatory mechanism of ferroptosis, providing new insights for research on regulating drugs and for the development of ferroptosis-targeting therapy for Alzheimer's disease, Parkinson's disease, cancer and cardiovascular disease.

Spatio-Temporal Feature Transformation Based Polyp Recognition for Automatic Detection: Higher Accuracy than Novice Endoscopists in Colorectal Polyp Detection and Diagnosis.

BACKGROUND: Artificial intelligence represents an emerging area with promising potential for improving colonoscopy quality. AIMS: To develop a colon polyp detection model using STFT and evaluate its performance through a randomized sample experiment. METHODS: Colonoscopy videos from the Digestive Endoscopy Center of the First Affiliated Hospital of Anhui Medical University, recorded between January 2018 and November 2022, were selected and divided into two datasets. To verify the model's practical application in clinical settings, 1500 colonoscopy images and 1200 polyp images of various sizes were randomly selected from the test set and compared with the STFT model's and endoscopists' recognition results with different years of experience. RESULTS: In the randomized sample trial involving 1500 colonoscopy images, the STFT model demonstrated significantly higher accuracy and specificity compared to endoscopists with low years of experience (0.902 vs. 0.809, 0.898 vs. 0.826, respectively). Moreover, the model's sensitivity was 0.904, which was higher than that of endoscopists with low, medium, or high years of experience (0.80, 0.896, 0.895, respectively), with statistical significance (P < 0.05). In the randomized sample experiment of 1200 polyp images of different sizes, the accuracy of the STFT model was significantly higher than that of endoscopists with low years of experience when the polyp size was ≤ 0.5 cm and 0.6-1.0 cm (0.902 vs. 0.70, 0.953 vs. 0.865, respectively). CONCLUSIONS: The STFT-based colon polyp detection model exhibits high accuracy in detecting polyps in colonoscopy videos, with a particular efficiency in detecting small polyps (≤ 0.5 cm)(0.902 vs. 0.70, P < 0.001).

Bowel function, quality of life, and mental health of patients with high-grade intraepithelial neoplasia or T1 colorectal cancer after organ-preserving versus organ-resection surgeries: a cross-sectional study at a Chinese tertiary care center.

BACKGROUND: This study aimed to determine the postoperative intestinal functioning, quality of life (QoL), and psychological well-being of patients treated either with organ-preserving surgery (OPS) or organ-resection surgery (ORS) for high-grade intraepithelial neoplasia (HIN) or T1 colorectal cancer (CRC). METHODS: This cross-sectional study was conducted at a single tertiary care center. In total, 175 eligible individuals with T1 CRC or HIN were divided into the OPS (n = 103) or ORS (n = 72) group based on whether the relevant segment of the intestine was preserved or resected. Intestinal function was evaluated using low anterior resection syndrome (LARS) scores. QoL was evaluated using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC-QLQ)-C30 and EORTC-QLQ-CR29. Psychological status was evaluated using the Fear of Progression Questionnaire-Short Form and the Self-rating Anxiety and Depression scales. Propensity score matching (PSM) was used to minimize the influence of potential confounders. RESULTS: Overall, 130 of 175 patients (74.29%) responded to the questionnaires; 56 and 74 were in the ORS and OPS groups, respectively. Thirty-five patient pairs were successfully matched through PSM. The mild and severe LARS rates were significantly higher in the ORS group than in the OPS group (P < 0.001). The EORTC-QLQ-C30 and EORTC-QLQ-CR29 scores revealed significantly better physical, role, and emotional functioning and an overall improved state of health (with multiple reduced symptom scores) in the OPS group than in the ORS group (P < 0.05). Significantly more patients were depressed in the ORS group than in the OPS group (P = 0.034), whereas anxiety or fear of disease progression did not differ significantly between the groups. CONCLUSIONS: OPS for the treatment of HIN or T1 CRC was found to be more advantageous for patients in terms of improved intestinal function, QoL, and psychological status than was ORS.

Analysis of Caregiver Burden and Influencing Factors in Autologous Hematopoietic Stem Cell Transplantation Patients with Bendamustine Preconditioning.

This paper comprehensively analyzes the caregiver burden and its influencing factors on primary caregivers in autologous hematopoietic stem cell transplantation (Auto-HSCT) with bendamustine preconditioning. Auto-HSCT refers to the transplantation of cells back to the patient, aiming to eliminate tumor cells and prolong the patient's life. Bendamustine, while enhancing the success rate of transplantation, has drawn considerable attention to the primary caregivers of patients. Due to the complex nature of the transplantation process, patients have diverse caregiving needs, which caregivers must address to support the entire treatment journey. The caregiver burden of primary caregivers is influenced by various factors, including the patient's disease condition, various aspects of the caregiver as an individual, and psychological factors. The article emphasizes the need for personalized care plans and psychological support to minimize caregiver burden and improve overall quality of life. This study has positive implications for optimizing the implementation of Auto-HSCT therapy.

Association of prenatal exposure to perfluorinated and polyfluoroalkyl substances with childhood neurodevelopment: A systematic review and meta-analysis.

BACKGROUND: Although previous studies have shown an association between prenatal exposure to perfluorinated and polyfluoroalkyl substances (PFAS) and neurodevelopmental disorders in children, the results have been inconsistent. We summarize studies on the association between prenatal PFAS exposure and neurodevelopment in children in order to better understand the relationship. OBJECTIVE: We conducted a meta-analysis of prenatal PFAS exposure and developmental outcomes associated with intellectual, executive function and behavioral difficulty in children to explore the relationship between prenatal exposure to perfluorinated and polyfluoroalkyl substances (PFAS) and neurodevelopmental disorders in children. METHODS: We searched for articles published up to August 3, 2023, included and quantified original studies on PFAS and child Intelligence Quotient (IQ), executive function and behavioral difficulty during pregnancy, and systematically summarized articles that could not be quantified. CONCLUSION: There is evidence of sex-specific relationship between PFAS exposure and children's PIQ. We found that PFOS [ß = -1.56, 95% CI = -2.96, - 0.07; exposure = per 1 ln (ng/ml) increase], PFOA [ß = -1.87, 95% CI = -3.29, - 0.46; exposure = per 1 ln (ng/ml) increase], PFHxS [ß = -2.02, 95% CI = -3.23, - 0.81; exposure = per 1 ln (ng/ml) increase] decreased performance IQ in boys, but PFOS [ß = 1.56, 95% CI = 0.06, 3.06; exposure = per 1 ln (ng/ml) increase] increased performance IQ in girls. PFAS are associated with executive function impairments in children, but not related to behavioral difficulty in children.

[Research progress of KCNJ5 gene in aldosterone-producing adenoma].

Aldosterone-producing adenoma is a subtype of primary aldosteronism. Recent advancements in multi-omics research have led to significant progress in understanding primary aldosteronism at the genetic level. Among the various genes associated with the development of aldosterone-producing adenomas, the KCNJ5 (potassium inwardly rectifying channel, subfamily J, member 5) gene has received considerable attention due to its prevalence as the most common somatic mutation gene in primary aldosteronism. This paper aims to integrate the existing evidence on the involvement of KCNJ5 gene in the pathogenesis of aldosterone-producing adenomas, to enhance the understanding of the underlying mechanisms of aldosterone-producing adenomas from the perspective of genetics, and to provide novel insights for the clinical diagnosis and treatment of aldosterone-producing adenomas.

Benefit from luteal phase progestin primed ovarian stimulation with clomiphene citrate supplementation in young women with diminished ovarian reserve: a retrospective study. / å¹´è½»åµå·¢å‚¨å¤‡åŠŸèƒ½å‡é€€æ‚£è€ åµæ³¡æœŸä¸Žé»„ä½“æœŸåº”ç”¨é«˜å­•æ¿€ç´ çŠ¶æ€è¶ ä¿ƒæŽ’åµæ–¹æ¡ˆæ•ˆæžœæ¯”è¾ƒ.

OBJECTIVES: To compare the pregnancy outcomes of luteal phase and follicular phase progestin-primed ovarian stimulation protocol with clomiphene citrate supplementation (LPPOS+CC and FPPOS+CC) in young women with diminished ovarian reserve (DOR). METHODS: A total of 483 women aged ≤35 years with DOR, who underwent in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI)/embryo transfer (ET) with controlled ovarian stimulation using LPPOS+CC (n=257) or FPPOS+CC (n=226) protocols during June 2018 and December 2021 at the First Affiliated Hospital of Wenzhou Medical University, were included in this retrospective study. The baseline characteristics, superovulation results, laboratory related indicators between the two groups, and the pregnancy outcomes of women who achieved at least one high-quality cleavage-stage embryo or good-morphology blastocyst were compared between the two groups. RESULTS: No statistically significant differences were identified between the groups with respect to age, duration of infertility, proportion of secondary infertility, previous failed cycles, body mass index, anti-Müllerian hormone, antral follicle count, basal luteinizing hormone level, basal progesterone level, number of oocytes retrieved, oocyte maturation rate, high-quality cleavage-stage embryo cycle rate, the percentage of women with profound pituitary suppression, live birth rate and preterm birth rate (all P>0.05). The LH levels on the day of trigger [4.0 (2.7, 5.3) vs. 5.1 (3.2, 7.2) IU/L], the percentage of women with LH levels of >10 IU/L on the trigger day (3.13% vs. 10.67%), and the two pronucleus (2PN) rate of ICSI oocytes (72.16% vs. 79.56%) were significantly lower in the LPPOS+CC group than those in the FPPOS+CC group (P<0.05 or P<0.01). The duration of stimulation [11 (9, 12) vs. 9 (8, 11) d], the consumption of total gonadotropin [2213 (1650, 2700) vs. 2000 (1575, 2325) IU], the progesterone levels on the day of trigger [1.3 (0.8, 2.9) vs. 0.9 (0.6, 1.2) ng/mL], the clinical pregnancy rate [61.88% vs. 46.84%], and implantation rate [42.20% vs. 31.07%] in the LPPOS+CC group were significantly higher than those in the FPPOS+CC group (all P<0.01). CONCLUSIONS: Compared to FPPOS+CC, the LPPOS+CC protocol appears to have better pregnancy outcomes for young women with DOR undergoing IVF/ICSI-ET.

Flavin-N5OOH Functions as both a Powerful Nucleophile and a Base in the Superfamily of Flavoenzymes.

Flavoenzymes can mediate a large variety of oxidation reactions through the activation of oxygen. However, the O2 activation chemistry of flavin enzymes is not yet fully exploited. Normally, the O2 activation occurs at the C4a site of the flavin cofactor, yielding the flavin C4a-(hydro)hydroperoxyl species in monooxygenases or oxidases. Using extensive MD simulations, QM/MM calculations and QM calculations, our studies reveal the formation of the common nucleophilic species, Flavin-N5OOH, in two distinct flavoenzymes (RutA and EncM). Our studies show that Flavin-N5OOH acts as a powerful nucleophile that promotes C-N cleavage of uracil in RutA, and a powerful base in the deprotonation of substrates in EncM. We reason that Flavin-N5OOH can be a common reactive species in the superfamily of flavoenzymes, which accomplish generally selective general base catalysis and C-X (X=N, S, Cl, O) cleavage reactions that are otherwise challenging with solvated hydroxide ion base. These results expand our understanding of the chemistry and catalysis of flavoenzymes.

miR-140 and miR-200 regulate the migratory heterogeneity of location-specific Schwann cell population.

Schwann cells are functional cells in nerve regeneration and are commonly used as seed cells in tissue engineering. Enhanced Schwann cell migration capacity improves recovery effects, and thus, the identification of Schwann cells with greater migration ability is of great importance. In the present study, we examined the biological activities of Schwann cells collected from rat sciatic nerves (SN) and dorsal root ganglia (DRG). Observations from transwell migration assay and wound healing assay demonstrate that DRG Schwann cells migrate at a faster speed as compared with SN Schwann cells. Sequencing and bioinformatics suggest that differentially expressed genes between SN and DRG Schwann cells are associated with cell motility and migration. miR-140 and miR-200, two microRNAs (miRNAs) that are highly expressed in SN Schwann cells negatively influence Schwann cell migration and thus may be key regulators of Schwann cell phenotype. Igsf10, Plxna2, and Lcp1 are screened as candidate downstream targets of miR-140 and miR-200 based on bioinformatic analysis and their expression correlation with miRNAs. Our comparative analysis displays the unique characteristics of Schwann cells in different anatomical localizations and demonstrates that DRG Schwann cells are suitable seed cells for tissue engineering and regenerative medicine.

Schwann cell-derived amphiregulin enhances nerve regeneration via supporting the proliferation and migration of Schwann cells and the elongation of axons.

Peripheral nerves have limited regeneration ability following nerve injury. Applying growth factors with neurotrophic roles is beneficial for accelerating peripheral nerve regeneration. Here we show that after rat sciatic nerve injury, growth factor amphiregulin (AREG) is upregulated in Schwann cells of sciatic nerves. Elevated AREG stimulates the proliferation and migration of Schwann cells by activating ERK1/2 cascade. Schwann cell-secreted AREG further facilitates the outgrowth of neurites and the elongation of injured axons. Administration of AREG to injured sciatic nerves stimulates the proliferation of Schwann cells to replace lost cell population, encourages the migration of Schwann cells to form cell cords, and facilitates the regrowth of axons. Overall, our results identify AREG as an important neurotrophic factor and thus provide a promising therapeutic avenue towards peripheral nerve injury.