Association of serum progesterone levels on the transfer day with pregnancy outcomes in hormone replacement frozen-thawed cycles with oral dydrogesterone for strengthened luteal phase support.

OBJECTIVE: To investigate the relationship between serum progesterone (P) levels on the day of blastocyst transfer and pregnancy outcomes in frozen-thawed embryo transfer (FET) cycles using hormone replacement therapy (HRT) with oral dydrogesterone for strengthened luteal phase support (LPS). MATERIALS AND METHODS: This was a retrospective study including 1176 FET cycles. All patients received 40 mg of intramuscular (IM) P daily for endometrium transformation plus oral dydrogesterone 10 mg BID from transfer day for strengthened LPS. Pregnancy outcomes were compared between serum P levels on the transfer day ≥10 ng/ml and <10 ng/ml. Furthermore, cycles were divided into 10 groups by deciles of P and ongoing pregnancy rate (OPR) was calculated in each group. Analyses using deciles of serum P were completed to see if these could create further prognostic power. RESULTS: No differences were observed in clinical pregnancy rates (CPRs), OPRs and live birth rates (LBRs) between serum P levels ≥10 ng/ml and <10 ng/ml. Patients with serum P levels <5.65 ng/ml (10th percentile) had a significantly lower OPR (48.31% vs. 58.98%, p = 0.03) and LBR (43.22% vs. 57.75%, p = 0.003) than the rest of the patients. Multivariate logistic regression analysis showed serum P levels on the transfer day were not associated with pregnancy outcomes. CONCLUSION: Measuring serum P levels on the day of HRT-FET is of clinical importance. Lower serum P levels impact the success of HRT-FET cycles, suggesting that there may be a threshold below which it is difficult to improve pregnancy outcomes via oral dydrogesterone to strengthen LPS.

Identifying Umami Peptides Specific to the T1R1/T1R3 Receptor via Phage Display.

Umami peptides are small molecular weight oligopeptides that play a role in umami taste attributes. However, the identification of umami peptides is easily limited by environmental conditions, and the abundant source and high chromatographic separation efficiency remain difficult. Herein, we report a robust strategy based on a phage random linear heptapeptide library that targets the T1R1-Venus flytrap domain (T1R1-VFT). Two candidate peptides (MTLERPW and MNLHLSF) were readily identified with high affinity for T1R1-VFT binding (KD of MW-7 and MF-7 were 790 and 630 nM, respectively). The two peptides exhibited umami taste and significantly enhanced the umami intensity when added to the monosodium glutamate solution. Overall, this strategy shows that umami peptides could be developed via phage display technology for the first time. The phage display platform has a promising application to discover other taste peptides with affinity for taste receptors of interest and has more room for improvement in the future.

H2O2 and Phosphorylated Peptide Dual-Responsive Nanochannel Device.

Oxidation and protein phosphorylation are critical mechanisms involved in regulating various cellular activities. Increasing research has suggested that oxidative stress could affect the activities of specific kinases or phosphatases, leading to alterations in the phosphorylation status of certain proteins. Ultimately, these alterations can affect cellular signaling pathways and gene expression patterns. However, the relationship between oxidation and protein phosphorylation remains complex and not yet fully understood. Therefore, the development of effective sensors capable of detecting both oxidation and protein phosphorylation simultaneously presents an ongoing challenge. To address this need, we introduce a proof-of-concept nanochannel device that is dual-responsive to both H2O2 and phosphorylated peptide (PP). Specifically, we design a peptide GGGCEG(GPGGA)4CEGRRRR, which contains an H2O2-sensitive unit CEG, an elastic peptide fragment (GPGGA)4, and a phosphorylation site recognition fragment RRRR. When the peptides are immobilized on the inner walls of conical nanochannels in a polyethylene terephthalate membrane, this peptide-modified nanochannel device exhibits a sensitive response to both H2O2 and PPs. The peptide chains undergo a random coil-to-α-helix transition in response to H2O2, which leads to a close-to-open transition of the nanochannel, accompanied with a remarkable increase in the transmembrane ionic current. In contrast, binding of the peptides with PPs shields the positive charge of the RRRR fragments, causing a decrease of the transmembrane ionic current. These unique features enable the sensitive detection of reactive oxygen species released by 3T3-L1 cells stimulated by platelet-derived growth factor (PDGF) as well as PDGF-induced change in the PP level. Real-time kinase activity monitoring further confirms the device's potential utility for kinase inhibitor screening.

Specific Clearance of Lipopolysaccharide from Blood Based on Peptide Bottlebrush Polymer for Sepsis Therapy.

Lipopolysaccharide (LPS) is the primary bacterial toxin that is vital to the pathogenesis and progression of sepsis associated with extremely high morbidity and mortality worldwide. However, specific clearance of LPS from circulating blood is highly challenging because of the structural complexity and its variation between/within bacterial species. Herein, a robust strategy based on phage display screening and hemocompatible peptide bottlebrush polymer design for specific clearance of targeted LPS from circulating blood is proposed. Using LPS extracted from Escherichia coli as an example, a novel peptide (HWKAVNWLKPWT) with high affinity (KD < 1.0 nм), specificity, and neutralization activity (95.9 ± 0.1%) against the targeted LPS is discovered via iterative affinity selection coupled with endotoxin detoxification screening. A hemocompatible bottlebrush polymer bearing the short peptide [poly(PEGMEA-co-PEP-1)] exhibits high LPS selectivity to reduce circulating LPS level from 2.63 ± 0.01 to 0.78 ± 0.05 EU mL-1 in sepsis rabbits via extracorporeal hemoperfusion (LPS clearance ratio > 70%), reversing the LPS-induced leukocytopenia and multiple organ damages significantly. This work provides a universal paradigm for developing a highly selective hemoadsorbent library fully covering the LPS family, which is promising to create a new era of precision medicine in sepsis therapy.

CT-guided microcoil localization of pulmonary nodules: the effect of the position of microcoil proximal end on the incidence of microcoil dislocation.

OBJECTIVES: To evaluate the effect of the position of microcoil proximal end on the incidence of microcoil dislocation during CT-guided microcoil localization of pulmonary nodules (PNs). METHODS: This retrospective study included all patients with PNs who received CT-guided microcoil localization before video-assisted thoracoscopic urgery (VATS) resection from June 2016 to December 2019 in our institution. The microcoil distal end was less than 1 cm away from the nodule, and the microcoil proximal end was in the pleural cavity (the pleural cavity group) or chest wall (the chest wall group). The length of microcoil outside the pleura was measured and divided into less than 0.5 cm (group A), 0.5 to 2 cm (group B) and more than 2 cm (group C). Microcoil dislocation was defined as complete retraction into the lung (type I) or complete withdrawal from the lung (type II). The rate of microcoil dislocation between different groups was compared. RESULTS: A total of 519 consecutive patients with 571 PNs were included in this study. According to the position of microcoils proximal end on post-marking CT, there were 95 microcoils in the pleural cavity group and 476 in the chest wall group. The number of microcoils in group A, B, and C were 67, 448 and 56, respectively. VATS showed dislocation of 42 microcoils, of which 30 were type II and 12 were type I. There was no statistical difference in the rate of microcoil dislocation between the pleural cavity group and the chest wall group (6.3% vs 7.6%, x2 = 0.18, p = 0.433). The difference in the rate of microcoil dislocation among group A, B, and C was statistically significant (11.9%, 5.8%, and 14.3% for group A, B, and C, respectively, x2 = 7.60, p = 0.008). In group A, 75% (6/8) of dislocations were type I, while all eight dislocations were type II in group C. CONCLUSIONS: During CT-guided microcoil localization of PNs, placing the microcoil proximal end in the pleura cavity or chest wall had no significant effect on the incidence of microcoil dislocation. The length of microcoil outside the pleura should be 0.5 to 2 cm to reduce the rate of microcoil dislocation. ADVANCES IN KNOWLEDGE:: CT-guided microcoil localization can effectively guide VATS to resect invisible and impalpable PNs. Microcoil dislocation is the main cause of localization failure. The length of microcoil outside the pleura is significantly correlated with the rate and type of microcoil dislocation. Placing the microcoil proximal end in the pleura cavity or chest wall has no significant effect on the rate of microcoil dislocation.

Self-assembly gel-based dynamic response system for specific recognition of N-acetylneuraminic acid.

Sialic acids located at the terminal end of glycans are densely attached to cell surfaces and play crucial and distinctive roles in a variety of physiological and pathological processes, such as neural development, cell-cell interactions, autoimmunity and cancers. However, due to the subtle structural differences of sialic acid species and the complicated composition of glycans, the precise recognition of sialylated glycans is difficult. Here, a fluorescent dynamic response system based on a pyrene-conjugated histidine (PyHis) supramolecular gel is proposed. Driven by π-π stacking and intermolecular hydrogen bonds, PyHis exhibits a strong self-assembly ability and forms stable gels. It is found that introduction of N-acetylneuraminic acid (a typical sialic acid) can prevent this self-assembly process, whereas other monosaccharides or sialic acid analogs have no significant effect on it. Interestingly, a sialylated glycan also has a remarkable inhibitory effect on the gel formation, which highlights the high selectivity of the gel dynamic response system. Analysis of the mechanism reveals that the sialic acid or sialylated glycan can interact closely with two PyHis molecules stacked together in the assemblies via hydrogen bonding interactions, thereby preventing the ordered accumulation of the gelators. It is worth noting that the high-efficiency sialic acid recognition effect is not observed at the single molecule level but at the supramolecular level, indicating the unique superiority of the supramolecular self-assembly system in biomolecular recognition and response. This work shows the promising prospects of using supramolecular gels in assembly engineering, regenerative medicine, tumour cell sorting and cancer diagnosis.

CT-guided transthoracic needle biopsy of pulmonary lesions: comparison between the cutting needle and aspiration needle.

OBJECTIVES: To compare CT-guided transthoracic cutting needle biopsy (TCNB) with transthoracic aspiration needle biopsy (TANB) for pulmonary lesions with respect to the diagnostic accuracy and complication rate. METHODS: Of the 859 cases that underwent consecutive CT-guided biopsy of pulmonary lesions, 713 cases confirmed by surgical pathology or clinical follow-up were enrolled. Of these, the first consecutive 275 cases underwent TANB, and the remaining 438 received TCNB. The final diagnosis determined the accuracy of biopsy. Based on the post-biopsy CT and clinical medical records, the presence or absence of biopsy-related complications was determined. The χ2 test was used to compare the differences between TCNB and TANB in terms of diagnostic accuracy and complication rate. RESULTS: Among the 713 biopsy lesions, the final diagnosis was malignant in 411 cases and benign in 302 cases. As compared to TANB, the diagnostic accuracy of TCNB (98.9% vs 93.8%, χ2 = 14.35, p < 0.01), sensitivity to malignant lesions (97.8% vs 90.6%, χ2 = 10.58, p < 0.01), negative predictive value (97.6% vs 84.8%, χ2 = 19.03, p < 0.01), and specific diagnostic rate for benign lesions (73.4% vs 57.9%, χ2 = 7.29, p < 0.01) were improved. On the other hand, a statistical difference was detected between TCNB and TANB with respect to the incidence of pneumothorax (20.6% vs 13.1%, χ2 = 6.46, p = 0.01), hemorrhage (32.2% vs 13.1%, χ2 = 33.03, p < 0.01), and hemoptysis (8.2% vs 3.3%, χ2 = 6.87, p < 0.01). One patient died just several minutes after TCNB due to severe hemorrhage with hemoptysis. CONCLUSIONS: Compared to TANB, CT-guided TCNB improves the diagnostic accuracy of pulmonary lesions, but complication rate increases significantly. ADVANCES IN KNOWLEDGE: In general, TCNB should be recommended, especially for highly suspicious benign lesions. For patients with small lesions adjacent to vessels or vessels within the lesion, TANB should be considered.

A methylation-inspired mesoporous coordination polymer for identification and removal of organic pollutants in aqueous solutions.

Qualitative analysis of contamination events and rapid removal of hazardous substances from water are in urgent need for a sustainable environment and human health. Porous coordination polymers (PCPs) bridged by organic ligands through metal nodes in an extendable and periodic manner have emerged as competitive candidates for the detection and removal of hazardous substances. However, the majority of them suffer from high production costs, poor structural stability and environmental problems, which has become a bottleneck for commercial translation. Here, we report a class of phenylalanine-based metal-biomolecule complexes and discuss the impact of subtle sequence variations in modular ligands on their assembly behaviors and structural properties. The phenomenon in which the bioligands dominate the structure formation and surface wettability has been revealed. A Cu(ii)-aspartame coordination polymer, Cu(mDF), with satisfactory chemical stability was selected for removal of organic pollutants in aqueous solution. The mesoporous structure, surface charge and high specific surface area (233.71 m2 g-1, Dmean = 5.65 nm) promote its rapid equilibrium of anionic adsorption within 10 min. In addition, Cu(mDF) possessing an adsorption-induced color-shifting feature provides an ideal platform for organic pollutant detection. Furthermore, Cu(mDF) with biocompatibility and low cost fabrication exhibits antimicrobial properties against C. albicans, E. coli and S. aureus, and may be a potential purifier in wastewater treatment.

Highly Efficient Separation of Methylated Peptides Utilizing Selective Complexation between Lysine and 18-Crown-6.

Protein methylation is one of the most common and important post-translational modifications, and it plays vital roles in epigenetic regulation, signal transduction, and chromatin metabolism. However, due to the diversity of methylation forms, slight difference between methylated sites and nonmodified ones, and ultralow abundance, it is extraordinarily challenging to capture and separate methylated peptides from biological samples. Here, we introduce a simple and highly efficient method to separate methylated and nonmethylated peptides using 18-crown-6 as a mobile phase additive in high-performance liquid chromatography. Selective complexation between lysine and 18-crown-6 remarkably increases the retention of the peptides on a C18 stationary phase, leading to an excellent baseline separation between the lysine methylated and nonmethylated peptides. A possible binding mechanism is verified by nuclear magnetic resonance titration, biolayer interferometry technology, and quantum chemistry calculation. Through establishment of a simple enrichment methodology, a good selectivity is achieved and four methylated peptides with greatly improved signal-to-noise (S/N) ratios are successfully separated from a complex peptide sample containing 10-fold bovine serum albumin tryptic digests. By selecting rLys N as an enzyme to digest histone, methylation information in the histone could be well identified based on our enrichment method. This study will open an avenue and provide a novel insight for selective enrichment of lysine methylated peptides in post-translational modification proteomics.

Extracellular Vesicles Derived from Mesenchymal Stem Cells Recover Fertility of Premature Ovarian Insufficiency Mice and the Effects on their Offspring.

It has been reported that extracellular vesicles (EVs) derived from human umbilical cord mesenchymal stem cells (HUCMSCs) can promote the proliferative and secretive functions of granulosa cells. In vivo study further demonstrated that EVs derived from HUCMSCs can not only promote the angiogenesis of ovarian tissue but also restore the function of an ovary of chemically induced premature ovarian insufficiency (POI) mice. However, no study investigates the effects of HUCMSCs derived EVs on fertility recovery of POI mice and evaluating their offspring. This study investigates the effects of HUCMSCs derived EVs on fertility recovery and the cognitive function of their offspring. A POI model was established by intraperitoneal injection of cyclophosphamide (CTX) and busulfan (BUS), and randomly divided into EVs-transplantation group (a single injection of 150 µg EVs proteins which suspended in 0.1 ml phosphate buffer saline [PBS] via tail vein), POI group (a single injection of 0.1 ml PBS via tail vein), and normal control group (a single injection of 0.1 ml PBS via tail vein without intraperitoneal injection of CTX and BUS). After EVs treatment, not only the ovarian function of POI mice recovered but also the fertility increased with less time to get pregnant, evaluating by in vitro fertilization and mating test. Cognitive behaviors of the offspring were similar among the three groups through the Y-maze test and novel object recognition task. An anti-apoptotic effect was identified through immunohistochemistry, real-time polymerase chain reaction and western blot. These findings indicate that HUCMSCs derived EVs can improve the fertility of POI mice without adverse effects on the cognitive behavior of their offspring, highlighting the potential value of EVs to be a cell-free therapy for patients suffering from POI.

cAMP sensitive nanochannels driven by conformational transition of a tripeptide-based smart polymer.

Inspired by biological nanochannels, a novel cyclic 3',5'-adenosine monophosphate (cAMP)-regulated artificial nanochannel based on a tripeptide Arg-Thr-Ala (RTA) design is developed. Highly specific binding between the tripeptide and cAMP triggers an obvious conformational transition of a smart polymer chain from a contracted state to a swollen one, which leads to a dynamic modulation of the gating behaviours of the nanochannels.

Molecular chirality mediated amyloid formation on phospholipid surfaces.

One of the neuropathological features of Alzheimer's disease (AD) is the misfolding of amyloid-ß to form amyloid aggregates, a process highly associated with biological membranes. However, how molecular chirality affects the amyloid formation on phospholipid surfaces has seldom been reported. Here, l- and d-aspartic acid-modified 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (l-/d-Asp-DPPE) is synthesized to construct chiral phospholipid bilayers. We discover that the l-Asp-DPPE liposomes slightly inhibit the Aß(1-40) nucleation process but cannot affect the oligomer elongation process. By contrast, the d-Asp-DPPE liposomes strongly inhibit both nucleation and elongation of the peptide. Notably, l- and d-Asp-DPPE liposomes not only have good biocompatibility but can also rescue Aß(1-40)-aggregation induced cytotoxicity with significant chiral discrimination, in which the cell viability is higher in the presence of d-Asp-DPPE liposomes. Mechanism analysis and molecular dynamics simulation clearly demonstrate that differential electrostatic interactions of Lys16 in Aß(1-40) with l- or d-Asp on the phospholipid contribute to the remarkable chiral discrimination. This study provides a deeper understanding of the crucial amyloidosis process from the perspective of the chiral interface and reveals that the convergence of d-amino acids with the liposomes might be a feasible route for AD prevention.

Therapeutic effects of human umbilical cord mesenchymal stem cell-derived microvesicles on premature ovarian insufficiency in mice.

BACKGROUND: Premature ovarian insufficiency (POI) is one of the leading causes of female infertility, which is caused by an abnormal ovarian reserve. Currently, there is no effective treatment to restore the fertility of POI patients. Recent studies suggested that microvesicles (MVs) released from mesenchymal stem cells (MSCs) exert therapeutic effects in various degenerative diseases. In this study, the effect of human umbilical cord MSC-derived MVs (HUCMSC-MVs) on the restoration of ovarian function in a chemotherapy-induced POI mouse model is investigated. METHODS: MVs were obtained from the supernatant of cultured HUCMSCs. The localization of PKH26-labeled HUCMSC-MVs in ovarian tissues was observed by confocal laser scanning microscopy. Histomorphometric analysis was performed to count the number of ovarian follicles and vessels. The ovarian sections were stained with anti-CD34 to evaluate angiogenesis. The levels of estradiol (E2) and follicle-stimulating hormone (FSH) were measured by enzyme-linked immunosorbent serologic assay. The mRNA expression of angiogenesis-related cytokines and the protein expression of AKT in mouse ovaries were measured by quantitative RT-PCR and western blot analysis. The parametric variables were compared by Student's t test and analysis of variance. The non-parametric variables were compared by the Mann-Whitney U test. Categorical variables were compared by χ2 test. P < 0.05 was considered statistically significant. RESULTS: PKH26-labeled HUCMSC-MVs were detectable within the ovaries and migrated to the ovarian follicles 24 h after transplantation. The transplantation of HUCMSC-MVs could increase the body weight and number of ovarian follicles (primordial, developing, and preovulatory follicles), induce ovarian angiogenesis, and recover the disturbed estrous cycle of POI mice. The expression levels of total AKT, p-AKT, and angiogenic cytokines (including VEGF, IGF, and angiogenin) in the ovaries of POI mice were markedly upregulated after HUCMSC-MVs transplantation, suggesting that HUCMSC-MVs transplantation might recover ovarian function by inducing angiogenesis via the PI3K/AKT signaling pathway. CONCLUSIONS: This study provides valuable insight into the effects of HUCMSC-MVs on ovarian tissue angiogenesis and on the restoration of ovarian function in POI mice, which may be helpful to develop a treatment strategy for POI patients.