Selectively superior production of docosahexaenoic acid in Schizochytrium sp. through engineering the fatty acid biosynthetic pathways.

BACKGROUND: Schizochytrium sp. is commercially used for production of docosahexaenoic acid (DHA). Schizochytrium sp. utilizes the polyketide synthase complex (PKS) and a single type I fatty acid synthase (FAS) to synthesize polyunsaturated fatty acids and saturated fatty acids, respectively. The acyl carrier protein (ACP) domains of FAS or PKS are used to load acyl groups during fatty acids biosynthesis. Phosphopantetheinyl transferase (PPTase) transfers the pantetheine moiety from Coenzyme A to the conserved serine residue of an inactive ACP domain to produce its active form. RESULTS: In this study, in order to improve production and content of DHA, we decreased the expression of fas, strengthened the expression of the PKS pathway, and enhanced the supply of active ACP in Schizochytrium sp. ATCC20888. Weakening the expression of fas or disruption of orfA both led to growth defect and reduction of lipid yields in the resulting strains WFAS and DPKSA, indicating that both FAS and PKS were indispensable for growth and lipid accumulation. Although WFAS had a higher DHA content in total fatty acids than the wild-type strain (WT), its growth defect and low DHA yield hinders its use for DHA production. Overexpression of the orfAB, orfC, orfC-DH (truncated orfC), or ppt promoted DHA and lipid production, respectively. The yields and contents of DHA were further increased by combined overexpression of these genes. Highest values of DHA yield (7.2 g/L) and DHA content (40.6%) were achieved in a recombinant OPKSABC-PPT, ⁓56.5% and 15.3% higher than the WT values, respectively. CONCLUSIONS: This study demonstrates that genetic engineering of the fatty acid biosynthetic pathways provides a new strategy to enhance DHA production in Schizochytrium.

Identifying the Potential Apoptotic Metabolites in Postmortem Beef Muscle by Targeted Metabolomics.

Apoptotic cells may release specific metabolites to act as messengers during the apoptotic process. This study represents the first attempt to identify potential apoptotic metabolites in postmortem muscle. Ninety potential apoptotic metabolites in beef were selected and analyzed through targeted metabolomics, with 84 of them exhibiting significant differences over the postmortem time. Following the addition of the mitochondria-targeted antiapoptotic agent mitoquinone to postmortem muscle, metabolomic analysis revealed that 73 apoptotic metabolites still underwent significant changes, even against the backdrop of altered apoptosis. Of these 73 apoptotic metabolites, 54 exhibited similar trends at various treatment times with adding mitoquinone, including lipids (6), amino acids (27), nucleosides (11), and carbohydrate and energy metabolism (10). Mitoquinone significantly reduced the levels of most apoptotic metabolites, and inhibition of apoptosis resulted in a significant decrease in the levels of numerous apoptotic metabolites. Consequently, these apoptotic metabolites are considered complementary to apoptosis in postmortem muscle, with their increased levels potentially promoting apoptosis. Noteworthy apoptotic metabolites, such as glycerol 3-phosphate, serine, AMP, ATP, GMP, and creatine, were identified as active signaling molecules that attract and recruit phagocytes during apoptosis, assisting in recognizing apoptotic cells by phagocytes. This study provides, for the first time, insights into potential apoptotic metabolites in postmortem muscle, contributing to a better understanding of meat biochemistry.

Association between hypertensive disorders and Bell's palsy in pregnancy: protocol for a systematic review and meta-analysis.

BACKGROUND: Bell's palsy is an idiopathic peripheral nerve palsy involving the facial nerve. Pregnancy, diabetes mellitus and hypertension are the risk factors for Bell's palsy. However, the association between hypertensive disorders and Bell's palsy during pregnancy or the puerperium remains unclear. This systematic review will comprehensively summarise the literature and evaluate the association between Bell's palsy and hypertensive disorders during pregnancy or the puerperium. METHODS AND ANALYSIS: Systematic searches of PubMed, MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials will be undertaken using prespecified search strategies. Observational studies (cross-sectional studies, cohort studies, case reports and series case reports) written in English that investigate the association between hypertensive disorders of late pregnancy and Bell's palsy during pregnancy or the puerperium will be included. Different authors will independently conduct the eligible study selection, perform data extraction and appraise the quality of included studies. Subgroup analysis will be carried out based on the age of pregnant women (≤35 years old, >35 years old), parity (primipara, multipara) and fetus number (singleton or multiple-gestation pregnancy). ETHICS AND DISSEMINATION: This review will be based on published literature, and thus there is no requirement for ethics approval. The results of this study will aid in the knowledge of the relationship between Bell's palsy during pregnancy or the puerperium and hypertensive disorders of late pregnancy. The results of this systematic review will be shared through publication in a peer-reviewed journal with good visibility for the field of obstetrics and presentations at academic conferences. PROSPERO REGISTRATION NUMBER: CRD42023422902.

Boosting Reactive Oxygen Species Formation Over Pd and VOδ Co-Modified TiO2 for Methane Oxidation into Valuable Oxygenates.

Direct photocatalytic methane oxidation into value-added products provides a promising strategy for methane utilization. However, the inefficient generation of reactive oxygen species (ROS) partly limits the activation of CH4 . Herein, it is reported that Pd and VOδ co-modified TiO2 enables direct and selective methane oxidation into liquid oxygenates in the presence of O2 and H2 . Due to the extra ROS production from the in situ formed H2 O2 , a highly improved yield rate of 5014 µmol g-1  h-1 for liquid oxygenates with a selectivity of 89.3% is achieved over the optimized Pd0.5 V0.2 -TiO2 catalyst at ambient temperature, which is much better than those (2682 µmol g-1  h-1 , 77.8%) without H2 . Detailed investigations also demonstrate the synergistic effect between Pd and VOδ species for enhancing the charge carrier separation and transfer, as well as improving the catalytic activity for O2 reduction and H2 O2 production.

Is robotic-assisted vaginectomy a better choice in vaginal high-grade squamous intraepithelial lesions than conventional laparoscopic surgery?

BACKGROUND: Vaginectomy has been shown to be effective for select patients with vaginal high-grade squamous intraepithelial lesions (HSIL) and is favored by gynecologists, while there are few reports on the robotic-assisted laparoscopic vaginectomy (RALV). The aim of this study was to evaluate the safety and treatment outcomes between RALV and the conventional laparoscopic vaginectomy (CLV) for patients with vaginal HSIL. METHODS: This retrospective cohort study was conducted in 109 patients with vaginal HSIL who underwent either RALV (RALV group) or CLV (CLV group) from December 2013 to May 2022. The operative data, homogeneous HPV infection regression rate and vaginal HSIL regression rate were compared between the two groups. Student's t-test, the Mann-Whitney U test, Pearson χ2 test or the Fisher exact test, Kaplan-Meier survival analysis and Cox proportional-hazards models were used for data analysis. RESULTS: There were 32 patients in the RALV group and 77 patients in the CLV group. Compared with the CLV group, patients in the RALV group demonstrated less estimated blood loss (41.6 ± 40.3 mL vs. 68.1 ± 56.4 mL, P = 0.017), lower intraoperative complications rate (6.3% vs. 24.7%, P = 0.026), and shorter flatus passing time (2.0 (1.0-2.0) vs. 2.0 (2.0-2.0), P < 0.001), postoperative catheterization time (2.0 (2.0-3.0) vs. 4.0 (2.0-6.0), P = 0.001) and postoperative hospitalization time (4.0 (4.0-5.0) vs. 5.0 (4.0-6.0), P = 0.020). In addition, the treatment outcomes showed that both RALV group and CLV group had high homogeneous HPV infection regression rate (90.0% vs. 92.0%, P > 0.999) and vaginal HSIL regression rate (96.7% vs. 94.7%, P = 0.805) after vaginectomy. However, the RALV group had significantly higher hospital costs than that in the CLV group (53035.1 ± 9539.0 yuan vs. 32706.8 ± 6659.2 yuan, P < 0.001). CONCLUSIONS: Both RALV and CLV can achieve satisfactory treatment outcomes, while RALV has the advantages of less intraoperative blood loss, fewer intraoperative complications rate and faster postoperative recovery. Robotic-assisted surgery has the potential to become a better choice for vaginectomy in patients with vaginal HSIL without regard to the burden of hospital costs.

Comparison of clinical outcomes and second-look hysteroscopy of the complete and incomplete septate uterus after hysteroscopic septoplasty.

PURPOSE: Septate uterus is the most common congenital uterine malformation. This retrospective cohort study compared clinical outcomes and second-look hysteroscopy findings in patients with complete and incomplete septate uteri after septoplasty. METHODS: We reviewed the medical records of patients with a septate uterus who underwent hysteroscopic septoplasty and second-look hysteroscopy at the West China Second University Hospital between September 2013 and September 2021. Information regarding pregnancy outcomes was collected through telephone interviews. The independent samples t-test, Mann-Whitney U test, Pearson's chi-square test, and Fisher's exact test were used to explore the differences between the complete and incomplete septate uterus groups. RESULTS: A total of 64 patients were enrolled in this study. There was no significant difference in intrauterine adhesion (IUA) rates (16.7% and 32.1%), pregnancy rates (44.1% and 42.9%), term delivery rates (35.3% and 32.1%), premature delivery rates (2.9% and 0), placenta previa rates (2.9% and 3.6%), placenta implantation/adhesion rates (5.9% and 3.6%), and premature rupture of membranes rates (2.9% and 0) between the complete and the incomplete group after hysteroscopic septoplasty (P > 0.05). Endometrial polyps in the septate uterus were common, with an incidence of 33.3% and 25% in the complete and incomplete groups, respectively (P > 0.05). CONCLUSION: The pregnancy outcomes of complete and incomplete septate uteri after hysteroscopic septoplasty were similar. There was no statistical difference in IUAs after surgery. Different treatment strategies may not be required for complete or incomplete septate uteri.

Effects of ohmic heating with different voltages on the quality and microbial diversity of cow milk during thermal treatment and subsequent cold storage.

Ohmic heating (OH), an innovative heating technology, presents potential applications in the pasteurization of liquid foods. Therefore, the study was conducted to evaluate the effect of OH at various voltage gradients (10 V/cm, 12.5 V/cm, and 15 V/cm) and water bath (WB) on microbial inactivation, physicochemical and sensory properties and microbial flora of pasteurized milk. Results indicated that OH with higher voltage could effectively inactivate microorganisms in milk, requiring less heating time and energy. Moreover, OH treatment at higher voltages could decelerate lipid oxidation and better maintain the sensory quality and essential amino acids content of milk. Additionally, all treatments significantly altered the microbial community, and during storage, the microbial community in milk treated with 10 V/cm and 12.5 V/cm OH remained relatively stable. OH treatments with voltage gradients exceeding 12.5 V/cm could effectively inactive microorganisms and maintain the quality attributes of milk.

bZIP transcription factor FabR: Redox-dependent mechanism controlling docosahexaenoic acid biosynthesis and H2O2 stress response in Schizochytrium sp.

Schizochytrium sp. is an important industrial strain for commercial production of docosahexaenoic acid (DHA), which plays essential physiological roles in infant development and human health. The regulatory network for DHA biosynthesis and lipid accumulation in Schizochytrium remains poorly understood. FabR (fatty acid biosynthesis repressor), a basic leucine zipper (bZIP) transcription factor, was transcriptionally downregulated under low-nitrogen condition. Deletion of fabR gene (mutant ΔfabR) increased production of total lipids and DHA by 30.1% and 46.5%, respectively. ΔfabR displayed H2O2 stress resistance higher than that of parental strain or complementation strain CfabR. FabR bound specifically to 7-bp pseudo-palindromic sequence 5'-ATTSAAT-3' in upstream regions and repressed transcription of fatty acid biosynthesis genes (acl, fas, pfa) and antioxidant defense genes (cat, sod1, sod2, gpx). DNA binding activity of FabR was regulated in a redox-dependent manner. Under oxidative condition, FabR forms intermolecular disulfide bonds between two Cys46 residues of dimers; its DNA binding activity is thereby lost, and the transcription of its target genes is enhanced through derepression. Our findings clarify the redox-dependent mechanism that modulates FabR activity governing lipid and DHA biosynthesis and H2O2 stress response in Schizochytrium.

A low-background and wash-free signal amplification F-CRISPR biosensor for sensitive quantitative and visible qualitative detection of Salmonella Typhimurium.

In traditional CRISPR-based biosensors, the cleavage-induced signal generation is insufficient because only a signals is generated at a CRISPR-induced cleavage. Herein, we developed an improved CRISPR/Cas12a-based biosensor with an enlarged signal generation which integrated the hybridization chain reaction (HCR) and low-background Förster Resonance Energy Transfer (FRET) signal output mode. The HCR with nucleic acid self-assembly capability was used as a signal carrier to load more signaling molecules. To get the best signal amplification, three different fluorescence signal output modes (fluorescence recovery, FRET and low-background FRET) generated by two fluoresceins, FAM and Cy5, were fully investigated and compared. The results indicated that the low-background FRET signal output mode with the strictest signal generation conditions yielded the highest signal-to-noise ratio (S/N) (19.17) and the most obvious fluorescence color change (from red to yellow). In optimal conditions, the proposed biosensor was successfully applied for Salmonella Typhimurium (S. Typhimurium) detection with 6 h (including 4 h for sample pre-treatment) from the initial target processing to the final detection result. The qualitative sensitivity, reliant on color changes, was 103 CFU/mL. The quantitative sensitivity, calculated by the fluorescence value, were 1.62 × 101 CFU/mL, 3.72 × 102 CFU/mL, and 8.71 × 102 CFU/mL in buffer solution, S. Typhimurium-spiked milk samples, and S.Typhimurium-spiked chicken samples, respectively. The excellent detection performance of the proposed biosensor endowed its great application potential in food and environment safety monitoring.

DNA Origami-Based Letterpress Printing of Gold Nanostructures with Predesigned Morphologies.

Creating customizable metallic nanostructures in a simple and controllable manner has been a long-standing goal in nanoscience. In this study, we use DNA origami as a letterpress printing plate and gold nanoparticles as ink to produce predesigned gold nanostructures. The letterpress plate is reusable, enabling the repetitive production of predesigned gold nanostructures. Furthermore, by modifying the DNA origami letterpress plate on magnetic beads, we can simplify the printing processes. We have successfully printed gold nanoparticle dimers, trimers, straight and quadrilateral tetramers, and other nanostructures. Our approach improves the flexibility and stability of metallic nanostructures, simplifying both their design and their operation. It promises universal applicability in the fabrication of metamaterials, biosensors, and surface plasma nanooptics.

Bactericidal efficacy difference between air and nitrogen cold atmospheric plasma on Bacillus cereus: Inactivation mechanism of Gram-positive bacteria at the cellular and molecular level.

As an emerging food processing technology, cold atmospheric plasma (CAP) has attracted great attention in the field of microbial inactivation. Although CAP has been proven to effectively inactivate a variety of foodborne pathogens, there is less research on the inactivation of Bacillus cereus, and the exact inactivation mechanism is still unclear. Elucidating the inactivation mechanism will help to develop and optimize this sterilization method, with the prospective application in industrialized food production. This study aims to explore the bactericidal efficacy difference between air and nitrogen CAP on B. cereus, a typical Gram-positive bacterium, and reveals the inactivation mechanism of CAP at the cellular and molecular level, by observing the change of the cell membrane, cell morphological damage, intracellular antioxidant enzyme activity and cellular biomacromolecules changes. The results showed that both air CAP and nitrogen CAP could effectively inactivate B. cereus, which was due to the reactive oxygen and nitrogen species (RONS) generated by the plasma causing bacterial death. The damage pathways of CAP on Gram-positive bacteria could be explained by disrupting the bacterial cell membrane and cell morphology, disturbing the intracellular redox homeostasis, and destroying biomacromolecules in the cells. The differences in active species generated by the plasma were the main reason for the different bactericidal efficiencies of air CAP and nitrogen CAP, where air CAP producing RONS with stronger oxidative capacity in a shorter time. This study indicates that air CAP is an effective, inexpensive and green technology for B. cereus inactivation, providing a basis for industrial application in food processing.

Solid-solution MAX phase TiVAlC assisted with impurity for enhancing hydrogen storage performance of magnesium hydride.

Although MXene catalysts etched from precursor MAX have greatly improved the hydrogen storage performance of magnesium hydride (MgH2), the use of dangerous and polluting etchers (such as hydrofluoric acid) and the direct removal of potentially catalytically active A-layer substances (such as Al) present certain limitations. Here, solid-solution MAX phase TiVAlC catalyst without etching treatment has been directly introduced into MgH2 system to improve the hydrogen storage performance. The optimal MgH2-10 wt% TiVAlC can release about 6.00 wt% hydrogen at 300 °C within 378 s and absorb about 4.82 wt% hydrogen at 175 °C within 900 s. After 50 isothermal hydrogen ab/desorption cycles, the excellent cyclic stability and capacity retention (6.4 wt%, 99.6%) can be found for MgH2-10 wt% TiVAlC. The superb catalytic activity of TiVAlC catalyst can be explained by abundant electron transfer at external interfaces with MgH2/Mg, which can be further enhanced by impurity phase Ti3AlC2 due to strong H affinity brought from abundant electron transfer at internal interfaces (Ti3AlC2/TiVAlC). The influence of impurity phase which is common in MAX phase on the overall activity of catalysts has been firstly studied here, providing a unique method for designing composite catalyst to improve hydrogen storage performance of MgH2.

Morphology Engineering of VS4 Microspheres as High-Performance Cathodes for Hybrid Mg2+/Li+ Batteries.

V-based sulfides are considered as potential cathode materials for Mg2+/Li+ hybrid ion batteries (MLIBs) due to their high theoretical specific capacities, unique crystal structure, and flexible valence adjustability. However, the formation of irreversible polysulfides, poor cycling performance, and severe structural collapse at high current densities impede their further development. Herein, VS4 microspheres with various controllable nanoarchitectures were successfully constructed via a facile solvothermal method by adjusting the amount of hydrochloric acid and were used as cathode materials for MLIBs. The VS4 microsphere self-assembled by bundles of paralleled-nanorods and some intersected-nanorods (VS4@NC-5) exhibits an outstanding initial discharge capacity of 805.4 mAh g-1 at 50 mA g-1 that is maintained at 259.1 mAh g-1 after 70 cycles. Moreover, the VS4@NC-5 cathode can deliver a superior rate capability (146.1 mAh g-1 at 2000 mA g-1) and ultralong cycling life (134.5 mAh g-1 at 2000 mA g-1 after 2000 cycles). The extraordinary electrochemical performance of VS4@NC-5 could be attributed to its special multi-hierarchical microsphere structure and the formation of N-doped carbon layers and V-C bonds, resulting in unobstructed ion diffusion channels, multidimensional electron transfer pathways, and enhancements of electrical conductivity and structure stability. Furthermore, the electrochemical reaction mechanism and phase conversion behavior of the VS4@NC-5 cathode at various states are investigated by a series of ex situ characterization methods. The VS4 well-designed through morphological engineering in this work can pave a way to explore more sulfides with high-rate performance and long cycling stability for energy storage devices.

Ruthenium-Manganese Solid Solution Oxide with Enhanced Performance for Acidic and Alkaline Oxygen Evolution Reaction.

Proton exchange membrane water electrolysers and alkaline exchange membrane water electrolysers for hydrogen production suffer from sluggish kinetics and the limited durability of the electrocatalyst toward oxygen evolution reaction (OER). Herein, a rutile Ru0.75 Mn0.25 O2-δ solid solution oxide featured with a hierarchical porous structure has been developed as an efficient OER electrocatalyst in both acidic and alkaline electrolyte. Specifically, compared with commercial RuO2 , the catalyst displays a superior reaction kinetics with small Tafel slope of 54.6 mV dec-1 in 0.5 M H2 SO4 , thus allowing a low overpotential of 237 and 327 mV to achieve the current density of 10 and 100 mA cm-2 , respectively, which is attributed to the enhanced electrochemically active surface area from the porous structure and the increased intrinsic activity owing to the regulated Ru>4+ proportion with Mn incorporation. Additionally, the sacrificial dissolution of Mn relieves the leaching of active Ru species, leading to the extended OER durability. Besides, the Ru0.75 Mn0.25 O2-δ catalyst also shows a highly improved OER performance in alkaline electrolyte, rendering it a versatile catalyst for water splitting.

Role of non­coding RNA intertwined with the Wnt/ß­catenin signaling pathway in endometrial cancer (Review).

Endometrial cancer (EC) ranks as the sixth most common malignancy in women around the world. Although low­grade and early­stage EC commonly have an excellent prognosis, ~20% of EC patients experience an unfavorable prognosis. Identifying the pathogenesis and novel therapeutic targets may help address this group of patients. Non­coding (nc)RNAs, such as long non­coding RNAs (lncRNAs), microRNAs and circular RNAs (circRNAs), have been associated with EC occurrence and development. In addition, the aberrant activation of the Wnt/ß­catenin signaling pathway can promote the proliferation, invasion, migration and epithelial­to­mesenchymal transition (EMT) of EC cells. The network of ncRNAs has also been demonstrated to inhibit or activate the Wnt/ß­catenin signaling pathway. In the present review, ncRNAs, the Wnt/ß­catenin signaling pathway, and their crosstalk in EC were summarized and highlighted. This information is expected to provide novel insights into improving the management of EC using RNA as therapeutics.

Inactivation mechanisms of atmospheric pressure plasma jet on Bacillus cereus spores and its application on low-water activity foods.

Bacillus cereus spore is one of the most easily contaminated bacterial spores in low-water activity foods such as black pepper. Atmospheric-pressure plasma jet (APPJ) has emerged as an emerging and promising method for microbial inactivation in food processing. This study aimed to investigate the efficacy of APPJ in inactivating spores under various treatment parameters and to examine the resulting alterations in spore structures and internal membrane properties. Meanwhile, the practical application of APPJ for spore inactivation in black pepper was also evaluated. The results indicated that air-APPJ had superior spore inactivation capability compared to N2 and O2-APPJ. After 20 min of APPJ treatment (50 L/min, 800 W, and 10 cm), the reduction in spore count (>2 log CFU/g) was significantly greater than that achieved by heat treatment (80℃). The damage of inner membranes was considered as the major reason of the dried spore inactivation by APPJ treatment. Moreover, it achieved a reduction in spore count of > 1 log CFU/g on inoculated black pepper without significantly affecting its color and flavor. Although the antioxidant activity of black pepper was slightly reduced, the overall quality of the product was not considerably affected by plasma treatment. This study concluded that APPJ is an effective technique for spore inactivation, offering promising potential for application in the decontamination of low-water activity foods.

Construction of TiO2/TiOF2 heterojunction as a cathode material for high-performance Mg2+/Li+ hybrid-ion batteries.

Anatase TiO2 has attracted significant interest as a cathode material for Mg-ion batteries or Mg2+/Li+ hybrid-ion batteries. However, owing to the semiconductor property and slower Mg2+ diffusion kinetics it still suffers from poor electrochemical performance. Herein, a TiO2/TiOF2 heterojunction consisting of in situ formed TiO2 sheets and TiOF2 rods, was prepared by adjusting the amount of HF in the hydrothermal process, and used as cathode of Mg2+/Li+ hybrid-ion battery. The TiO2/TiOF2 heterojunction prepared by adding 2 mL HF (TiO2/TiOF2-2) exhibits high electrochemical performance, with a high initial discharge capacity (378 mAh/g at 50 mA/g), an outstanding rate performance (128.8 mAh/g at 2000 mA/g), and good cycle stability (capacity retention of 54 % after 500 cycles), which is much superior to that of Pure TiO2 and Pure TiOF2. The reactions of Li+ intercalation/detercalation in the TiO2/TiOF2 heterojunction are revealed by investigating the evolution of the hybrids during different electrochemical states. Moreover, theoretical calculations prove that the Li+ formation energy in the TiO2/TiOF2 heterostructure is much lower than that of TiO2 and TiOF2, demonstrating that the heterostructure plays a crucial role in the enhanced electrochemical performance. This work provides a novel method to design cathode materials with high performance by constructing heterostructure.

Natural history and malignant potential of simple ovarian cysts in postmenopausal women: a systematic review and meta-analysis.

IMPORTANCE: Postmenopausal ovarian masses are not uncommon, and the incidence of ovarian cancer rises sharply after menopause. OBJECTIVE: We conducted a systematic review and meta-analysis to investigate the natural history and malignant potential of postmenopausal simple ovarian cysts. EVIDENCE REVIEW: PubMed, MEDLINE, EMBASE, CENTRAL (Cochrane Central Register of Controlled Trials), ClinicalTrials.gov , and ISRCTN (International Standard Randomized Controlled Trial Number Register) were searched from inception to January 31, 2022. Meta-analyses were conducted using R software. FINDINGS: Twelve cohort studies with 1,672 participants and 1,513 ovarian cysts were included. The rates of simple cysts remaining unchanged (38.90%; 95% CI, 19.79%-59.85%; P < 0.01) or disappearing (34.17%; 95% CI, 19.13%-50.93%; P < 0.01) were the highest during conservative observation. The surgery rate for the simple cyst was 19.04% (95% CI, 8.19%-32.92%; P < 0.01). The malignancy rate (including borderline tumors) was very low, approximately 1/10,000 (95% CI, 0% to 0.23%; P = 0.79). CONCLUSIONS: Simple ovarian cysts in postmenopausal women were most likely to remain unchanged or disappear during follow-up. The malignancy rate was approximately 1 in 10,000. Personal preference is the most common reason for surgery.

Muscle fiber characteristics and apoptotic factor differences in beef Longissimus lumborum and Psoas major during early postmortem.

This study was conducted to study muscle fiber characteristics and apoptotic factor differences within 24 h postmortem of bovine longissimus lumborum (LL) and psoas major (PM). Compared to LL, PM had a higher proportion of type I fibers and lower proportion of type II fibers. PM also had higher ROS levels. For bcl-2 family proteins, anti-apoptotic BCL-2 level was lower and pro-apoptotic BAX level was higher in PM. For caspases, at 1 h postmortem, gene and protein expression level of caspase-3 and caspase-9 was higher in PM than that of LL. The levels of DNA damage apoptotic factors ABL1, AIF and ENDOG was higher in PM than in LL. The results suggested that apoptotic gene and protein expression were different in muscles with different fiber type composition. These findings provided insights into muscle fiber and apoptotic factor differences during early postmortem in bovine PM and LL.

A CRISPR/Cas12a-mediated, DNA extraction and amplification-free, highly direct and rapid biosensor for Salmonella Typhimurium.

CRISPR/Cas-based biosensors were typically used for nucleic-acid targets detection and complex DNA extraction and amplification procedures were usually inevitable. Here, we report a CRISPR/Cas12a-mediated, DNA extraction and amplification-free, highly direct and rapid biosensor (abbreviated as "CATCHER") for Salmonella Typhimurium (S. Typhimurium) with a simple (3 steps) and fast (∼2 h) sensing workflow. Magnetic nanoparticle immobilized anti-S. Typhimurium antibody was worked as capture probe to capture the target and provide movable reaction interface. Colloidal gold labeled with anti-S. Typhimurium antibody and DNase I was used as detection probe to bridge the input target and output signal. First, in the presence of S. Typhimurium, an immuno-sandwich structure was formed. Second, DNase I in sandwich structure degraded the valid, complete activator DNA to invalid DNA fragments which can't trigger the trans-cleavage activity of Cas12a. Finally, the integrity of reporter DNA was preserved presenting a low fluorescence signal. Conversely, in the absence of S. Typhimurium, strong fluorescence recovery appeared owing to the cutting of reporter by activated Cas12a. Significantly, the proposed "CATCHER" showed satisfactory detection performance for S. Typhimurium with the limit of detection (LOD) of 7.9 × 101 CFU/mL in 0.01 M PBS and 6.31 × 103 CFU/mL in spiked chicken samples, providing a general platform for non-nucleic acid targets.