ABSTRACT
The plasma membrane is crucial to the survival of animal cells, and damage to it can be lethal, often resulting in necrosis. However, cells possess multiple mechanisms for repairing the membrane, which allows them to maintain their integrity to some extent, and sometimes even survive. Interestingly, cells that survive a near-necrosis experience can recognize sub-lethal membrane damage and use it as a signal to secrete chemokines and cytokines, which activate the immune response. This review will present evidence of necrotic cell survival in both in vitro and in vivo systems, including in C. elegans, mouse models, and humans. We will also summarize the various membrane repair mechanisms cells use to maintain membrane integrity. Finally, we will propose a mathematical model to illustrate how near-death experiences can transform dying cells into innate immune modulators for their microenvironment. By utilizing their membrane repair activity, the biological effects of cell death can extend beyond the mere elimination of the cells.
Subject(s)
Caenorhabditis elegans , Immunity, Innate , Humans , Animals , Mice , Necrosis/metabolism , Cell Death , Cell Membrane/metabolismABSTRACT
Systemic administration of adeno-associated virus (AAV) vectors for spinal cord gene therapy has challenges including toxicity at high doses and pre-existing immunity that reduces efficacy. Intrathecal (IT) delivery of AAV vectors into cerebral spinal fluid can avoid many issues, although distribution of the vector throughout the spinal cord is limited, and vector entry to the periphery sometimes initiates hepatotoxicity. Here we performed biopanning in non-human primates (NHPs) with an IT injected AAV9 peptide display library. We identified top candidates by sequencing inserts of AAV DNA isolated from whole tissue, nuclei, or nuclei from transgene-expressing cells. These barcoded candidates were pooled with AAV9 and compared for biodistribution and transgene expression in spinal cord and liver of IT injected NHPs. Most candidates displayed increased retention in spinal cord compared with AAV9. Greater spread from the lumbar to the thoracic and cervical regions was observed for several capsids. Furthermore, several capsids displayed decreased biodistribution to the liver compared with AAV9, providing a high on-target/low off-target biodistribution. Finally, we tested top candidates in human spinal cord organoids and found them to outperform AAV9 in efficiency of transgene expression in neurons and astrocytes. These capsids have potential to serve as leading-edge delivery vehicles for spinal cord-directed gene therapies.
Subject(s)
Dependovirus , Genetic Therapy , Genetic Vectors , Spinal Cord , Dependovirus/genetics , Animals , Spinal Cord/metabolism , Genetic Vectors/administration & dosage , Genetic Vectors/genetics , Humans , Genetic Therapy/methods , Transgenes , Gene Transfer Techniques , Capsid/metabolism , Tissue Distribution , Injections, Spinal , Transduction, Genetic , Macaca mulatta , Capsid Proteins/genetics , Capsid Proteins/metabolismABSTRACT
BACKGROUND: Fibrogenesis within ovarian endometrioma (endometrioma), mainly induced by transforming growth factor-ß (TGF-ß), is characterized by myofibroblast over-activation and excessive extracellular matrix (ECM) deposition, contributing to endometrioma-associated symptoms such as infertility by impairing ovarian reserve and oocyte quality. However, the precise molecular mechanisms that underpin the endometrioma- associated fibrosis progression induced by TGF-ß remain poorly understood. METHODS: The expression level of lysine acetyltransferase 14 (KAT14) was validated in endometrium biopsies from patients with endometrioma and healthy controls, and the transcription level of KAT14 was further confirmed by analyzing a published single-cell transcriptome (scRNA-seq) dataset of endometriosis. We used overexpression, knockout, and knockdown approaches in immortalized human endometrial stromal cells (HESCs) or human primary ectopic endometrial stromal cells (EcESCs) to determine the role of KAT14 in TGF-ß-induced fibrosis. Furthermore, an adeno-associated virus (AAV) carrying KAT14-shRNA was used in an endometriosis mice model to assess the role of KAT14 in vivo. RESULTS: KAT14 was upregulated in ectopic lesions from endometrioma patients and predominantly expressed in activated fibroblasts. In vitro studies showed that KAT14 overexpression significantly promoted a TGF-ß-induced profibrotic response in endometrial stromal cells, while KAT14 silencing showed adverse effects that could be rescued by KAT14 re-enhancement. In vivo, Kat14 knockdown ameliorated fibrosis in the ectopic lesions of the endometriosis mouse model. Mechanistically, we showed that KAT14 directly interacted with serum response factor (SRF) to promote the expression of α-smooth muscle actin (α-SMA) by increasing histone H4 acetylation at promoter regions; this is necessary for TGF-ß-induced ECM production and myofibroblast differentiation. In addition, the knockdown or pharmacological inhibition of SRF significantly attenuated KAT14-mediating profibrotic effects under TGF-ß treatment. Notably, the KAT14/SRF complex was abundant in endometrioma samples and positively correlated with α-SMA expression, further supporting the key role of KAT14/SRF complex in the progression of endometrioma-associated fibrogenesis. CONCLUSION: Our results shed light on KAT14 as a key effector of TGF-ß-induced ECM production and myofibroblast differentiation in EcESCs by promoting histone H4 acetylation via co-operating with SRF, representing a potential therapeutic target for endometrioma-associated fibrosis.
Subject(s)
Endometriosis , Fibrosis , Serum Response Factor , Transforming Growth Factor beta , Adult , Animals , Female , Humans , Mice , Endometriosis/pathology , Endometriosis/metabolism , Endometrium/metabolism , Endometrium/pathology , Histone Acetyltransferases/metabolism , Myofibroblasts/metabolism , Myofibroblasts/pathology , Serum Response Factor/metabolism , Stromal Cells/metabolism , Stromal Cells/pathology , Transforming Growth Factor beta/metabolism , Up-Regulation/drug effects , Adaptor Proteins, Signal Transducing/metabolismABSTRACT
Oligotrophic deep-water lakes are unique and sensitive ecosystems with limited nutrient availability. Understanding bacterial communities within these lakes is crucial for assessing ecosystem health, biogeochemical cycling, and responses to environmental changes. In this study, we investigated the seasonal and vertical dynamics of both free-living (FL) and particle-attached (PA) bacteria in Lake Fuxian, a typical oligotrophic deep freshwater lake in southeast China. Our findings revealed distinct seasonal and vertical dynamics of FL and PA bacterial communities, driven by similar physiochemical environmental factors. PA bacteria exhibited higher α- and ß-diversity and were enriched with Proteobacteria, Cyanobacteria, Firmicutes, Patescibacteria, Planctomycetota, and Verrucomicrobiota, while FL bacteria were enriched with Actinobacteria and Bacteroidota. FL bacteria showed enrichment in putative functions related to chemoheterotrophy and aerobic anoxygenic photosynthesis, whereas the PA fraction was enriched with intracellular parasites (mainly contributed by Rickettsiales, Chlamydiales, and Legionellales) and nitrogen metabolism functions. Deterministic processes predominantly shaped the assembly of both FL and PA bacterial communities, with stochastic processes playing a greater role in the FL fraction. Network analysis revealed extensive species interactions, with a higher proportion of positively correlated edges in the PA network, indicating mutualistic or cooperative interactions. Cyanobium, Comamonadaceae, and Roseomonas were identified as keystone taxa in the PA network, underscoring potential cooperation between autotrophic and heterotrophic bacteria in organic particle microhabitats. Overall, the disparities in bacterial diversity, community composition, putative function, and network characteristics between FL and PA fractions highlight their adaptation to distinct ecological niches within these unique lake ecosystems.IMPORTANCEUnderstanding the diversity of microbial communities, their assembly mechanisms, and their responses to environmental changes is fundamental to the study of aquatic microbial ecology. Oligotrophic deep-water lakes are fragile ecosystems with limited nutrient resources, rendering them highly susceptible to environmental fluctuations. Examining different bacterial types within these lakes offers valuable insights into the intricate mechanisms governing community dynamics and adaptation strategies across various scales. In our investigation of oligotrophic deep freshwater Lake Fuxian in China, we explored the seasonal and vertical dynamics of two bacterial types: free-living (FL) and particle-attached (PA). Our findings unveiled distinct patterns in the diversity, composition, and putative functions of these bacteria, all shaped by environmental factors. Understanding these subtleties provides insight into bacterial interactions, thereby influencing the overall ecosystem functioning. Ultimately, our research illuminates the adaptation and roles of FL and PA bacteria within these unique lake environments, contributing significantly to our broader comprehension of ecosystem stability and health.
Subject(s)
Bacteria , Lakes , Microbiota , Lakes/microbiology , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , China , Ecosystem , SeasonsABSTRACT
We report an H-bond donor controlled diastereoselective switchable intramolecular aza-Henry reaction of ketimines derived from α-ketoesters and 2-(2-nitroethyl)anilines, allowing facile access to chiral tetrahydroquinolines bearing an aza-quaternary carbon stereocenter, which are privileged scaffold for medicinal researches. While newly developed cinchona alkaloid derived phosphoramide-bearing quaternary ammonium salt C2 selectively give cis-adducts in up to 20:1 dr and 99% ee, the corresponding urea-bearing analogue C8 preferentially give trans-adducts in up to 20:1 dr and 99% ee.
ABSTRACT
In this paper, we introduced a novel phase-transfer strategy tailored for the efficient batch detection of ascorbic acid in vitamin C tablets. This method entailed the reaction between ascorbic acid and an excess of potassium permanganate. Subsequent reaction of the residual potassium permanganate with sodium oxalate in an acidic medium led to the generation of carbon dioxide. The quantification of the produced carbon dioxide was achieved using headspace GC, enabling the indirect measurement of ascorbic acid. The obtained findings revealed that the headspace method exhibited satisfied precision with a relative standard deviation of less than 2.11% and high sensitivity with a limit of quantitation of 0.27 µmol. These results firmly establish the reliability of this innovative approach for determining ascorbic acid. In addition, the highly automated feature of headspace method significantly enhances the efficiency of batch sample detection and reduces the errors caused by human operation. Thus, the adoption of the transformed phase strategy has demonstrated its effectiveness in assessing ascorbic acid, especially for large-scale sample analysis in industrial applications, owing to its efficiency, precision, and sensitivity.
ABSTRACT
The global plastic waste problem is pushing for the development of sustainable alternatives, encouraged by stringent regulations combined with increased environmental consciousness. In response, this study presents an industrial-scale proof of concept to produce self-standing, transparent, and flexible bioplastic films, offering a possible solution to plastic pollution and resource valorization. We achieve this by combining amyloid fibrils self-assembled from food waste with methylcellulose and glycerol. Specifically, soy whey and okara, two pivotal protein-rich byproducts of tofu manufacturing, emerge as sustainable and versatile precursors for amyloid fibril formation and bioplastic development. An exhaustive industrial-scale feasibility study involving the transformation of 500 L of soy whey into â¼1 km (27 kg) of bioplastic films underscores the potential of this technology. To extend the practicality of our approach, we further processed a running kilometer of film at the industrial scale into transparent windows for paper-based packaging. The mechanical properties and the water interactions of the novel film are tested and compared with those of commercially used plastic films. By pioneering the large-scale production of biodegradable bioplastics sourced from food byproducts, this work not only simultaneously addresses the dual challenges of plastic pollution and food waste but also practically demonstrates the feasibility of biopolymeric building block valorization for the development of sustainable materials in real-world scenarios.
Subject(s)
Food , Refuse Disposal , Biopolymers , Product Packaging , PlasticsABSTRACT
In aquatic ecosystems with low nutrient levels, organic aggregates (OAs) act as nutrient hotspots, hosting a diverse range of microbial species compared to those in the water column. Lake eutrophication, marked by intensified and prolonged cyanobacterial blooms, significantly impacts material and energy cycling processes, potentially altering the ecological traits of both free-living (FL) and particle-attached (PA) bacteria. However, the extent to which observed patterns of FL and PA bacterial diversity, community assembly, and stability extend to hypereutrophic lakes remains understudied. To address this gap, we investigated bacterial diversity, composition, assembly processes, and stability within hypereutrophic Lake Xingyun. Our results revealed that FL bacterial communities exhibited higher α-diversity than PA counterparts, coupled with discernible taxonomic compositions. Both bacterial communities showed distinct seasonality, influenced by cyanobacterial bloom intensity. Environmental factors accounted for 71.1% and 54.2% of the variation among FL and PA bacteria, respectively. The assembly of the PA bacterial community was predominantly stochastic, while FL assembly was more deterministic. The FL network demonstrated greater stability, complexity, and negative interactions, indicative of competitive relationships, while the PA network showed a prevalence of positive correlations, suggesting mutualistic interactions. Importantly, these findings differ from observations in oligotrophic, mesotrophic, and eutrophic lakes. Overall, this research provides valuable insights into the interplay among bacterial fractions, enhancing our understanding of nutrient status and cyanobacterial blooms in shaping bacterial communities.
Subject(s)
Bacteria , Biodiversity , Cyanobacteria , Eutrophication , Lakes , Microbiota , Lakes/microbiology , Cyanobacteria/genetics , Cyanobacteria/classification , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , RNA, Ribosomal, 16S/genetics , Seasons , Ecosystem , ChinaABSTRACT
It is necessary to predict the critical transition of lake ecosystems due to their abrupt, non-linear effects on social-economic systems. Given the promising application of paleolimnological archives to tracking the historical changes of lake ecosystems, it is speculated that they can also record the lake's critical transition. We studied Lake Dali-Nor in the arid region of Inner Mongolia because of the profound shrinking the lake experienced between the 1300 s and the 1600 s. We reconstructed the succession of bacterial communities from a 140-cm-long sediment core at 4-cm intervals and detected the critical transition. Our results showed that the historical trajectory of bacterial communities from the 1200 s to the 2010s was divided into two alternative states: state1 from 1200 to 1300 s and state2 from 1400 to 2010s. Furthermore, in the late 1300 s, the appearance of a tipping point and critical slowing down implied the existence of a critical transition. By using a multi-decadal time series from the sedimentary core, with general Lotka-Volterra model simulations, local stability analysis found that bacterial communities were the most unstable as they approached the critical transition, suggesting that the collapse of stability triggers the community shift from an equilibrium state to another state. Furthermore, the most unstable community harbored the strongest antagonistic and mutualistic interactions, which may imply the detrimental role of interaction strength on community stability. Collectively, our study showed that sediment DNA can be used to detect the critical transition of lake ecosystems.
Subject(s)
Bacteria , DNA, Bacterial , Geologic Sediments , Lakes , Lakes/microbiology , Lakes/chemistry , Geologic Sediments/microbiology , Bacteria/genetics , Bacteria/classification , Bacteria/isolation & purification , China , DNA, Bacterial/genetics , Ecosystem , RNA, Ribosomal, 16S/genetics , MicrobiotaABSTRACT
BACKGROUND: Hepatocellular carcinoma (HCC) is experiencing a concerning rise in both incidence and mortality rates. Current therapeutic strategies are limited in their effectiveness, largely due to the complex causes of the disease and significant levels of drug resistance. Given the latest developments in human umbilical cord mesenchymal stem cells (hUC-MSCs) research, there is a debate over the continued use of stem cell transplantation for treating tumors. Consequently, this study seeks to explore the role of hUC-MSCs in the management of HCC. METHODS AND RESULTS: HUC-MSCs increased the number (10.75 ± 1.50) in the DEN/TCPOBOP-induced mice hepatoma model, compared with DMSO group (7.25 ± 1.71). Moreover, the liver index in hUC-MSCs group (0.21 ± 0.06) was greater than that in DMSO group (0.09 ± 0.01). Immunohistochemical (IHC) analysis revealed that while hUC-MSCs did not alter Foxp3 expression, they significantly stimulated Ki67 expression, indicative of increased tumor cellular proliferation. Additionally, immunofluorescence (IF) studies showed that hUC-MSCs increased CD8+ T cell counts without affecting macrophage numbers. Notably, granzyme B expression remained nearly undetectable. We observed that serum IL-18 levels were higher in the hUC-MSCs group (109.66 ± 0.38 pg/ml) compared to the DMSO group (91.14 ± 4.37 pg/ml). Conversely, IL-1ß levels decreased in the hUC-MSCs group (63.00 ± 0.53 pg/ml) relative to the DMSO group (97.38 ± 9.08 pg/ml). CONCLUSIONS: According to this study, hUC-MSCs promoted the growth of liver tumors. Therefore, we proposed that hUC-MSCs are not suitable for treating HCC, as they exhibit clinically prohibited abnormalities.
Subject(s)
Carcinoma, Hepatocellular , Cell Proliferation , Interleukin-18 , Liver Neoplasms , Mesenchymal Stem Cells , Umbilical Cord , Mesenchymal Stem Cells/metabolism , Humans , Animals , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/therapy , Carcinoma, Hepatocellular/metabolism , Umbilical Cord/cytology , Interleukin-18/metabolism , Liver Neoplasms/pathology , Liver Neoplasms/metabolism , Liver Neoplasms/therapy , Mice , Mesenchymal Stem Cell Transplantation/methods , Male , Cell Line, Tumor , CD8-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/immunologyABSTRACT
BACKGROUND: About 25% of pregnant women experience bleeding in the early stage, and half of them eventually progress to pregnancy loss. Progesterone serves as a useful biomarker to predict miscarriage in threatened miscarriage, yet its performance is still debated. AIM: To evaluate the performance of single serum progesterone predicting miscarriage in early pregnant patients with threatened miscarriage. METHOD: The online database was searched to yield the literature using the terms of 'Abortion', 'Miscarriage', and 'serum Progesterone', including PubMed, Scopus, Embase, Cochrane library, and China national knowledge infrastructure. Receiver operating characteristic (ROC) curve, likelihood ratio (LLR) and diagnostic odds ratio (DOR) and 95% confidence interval (CI) were computed. Publication bias was assessed by the deeks funnel plot asymmetry test. Subgroup analyses were conducted according to the progesterone level (< 12 ng/mL), recruited location and region, progesterone measurement method, exogenous progesterone supplement and follow up. RESULTS: In total, 12 studies were eligible to be included in this study, with sample sizes ranging from 76 to 1087. The included patients' gestational age was between 4 and 12 weeks. No significant publication bias was detected from all included studies. The threshold of progesterone reported ranged from 8 to 30 ng/ml. The synthesized area under the ROC curve (0.85, 95% CI 0.81 to 0.88), positive LLR (6.2, 4.0 to 9.7) and DOR (18, 12 to 27) of single progesterone measurement distinguishing miscarriage were relatively good in early pregnant patients with threatened miscarriage. When the threshold of < 12 ng/mL was adapted, the progesterone provided a higher area under the ROC curve (0.90 vs. 0.78), positive LLR (8.3 vs. 3.8) and DOR (22 vs.12) than its counterpart (12 to 30 ng/mL). CONCLUSION: Single progesterone measurement can act as a biomarker of miscarriage in early pregnant patients with threatened miscarriage, and it has a better performance when the concentration is <12 ng/mL. TRIAL REGISTRATION: PROSPERO (CRD42021255382).
Subject(s)
Abortion, Threatened , Biomarkers , Progesterone , Humans , Progesterone/blood , Pregnancy , Female , Abortion, Threatened/blood , Abortion, Threatened/diagnosis , Biomarkers/blood , Abortion, Spontaneous/blood , Predictive Value of Tests , Pregnancy Trimester, First/bloodABSTRACT
PURPOSE: To evaluate macular sensitivity using microperimetry in patients with proliferate diabetic retinopathy following vitrectomy and to investigate the relationship between the sensitivity and foveal microstructures with optical coherence tomography/angiography. METHODS: Eighty-four eyes of 84 patients with proliferative diabetic retinopathy, who were indicated for vitrectomy, had no intraocular surgery history 3 months preoperatively, and were able to ensure fundus examination after the vitrectomy, were included. A logMAR best-corrected visual acuity, macular sensitivity of microperimetry, macular retinal thickness, and macular vessel perfusion using optical coherence tomography/angiography were examined at 1 week, 1 month, and 3 months postoperatively. RESULTS: The logMAR best-corrected visual acuity and mean macular sensitivity of patients with proliferative diabetic retinopathy improved postoperatively (P < 0.05). There was a significant correlation between best-corrected visual acuity and mean sensitivity (P < 0.05). Postoperative mean macular sensitivity was significantly correlated with outer retinal thickness in the 0 to 6 mm macular area (P < 0.05) and also significantly correlated with deep capillary plexus perfusion (P < 0.05). Fixation stability and mean macular sensitivity did not show any correlation with glycated hemoglobin, triglyceride, serum total cholesterol, carbamide, and creatinine and duration of diabetes mellitus (P > 0.05). CONCLUSION: Postoperative mean macular sensitivity was significantly correlated with outer retinal thickness and deep capillary plexus perfusion for patients with proliferative diabetic retinopathy. The authors found that the visual performance of patients can be evaluated by the outer retinal thickness and deep capillary plexus perfusion, so optical coherence tomography/angiography examination can be an important prognostic factor for visual performance in patients.Clinical Trial Registration: This trial is registered with the Chinese Clinical Trial Registry (http://www.chictr.org.cn; Registration No.: ChiCTR2100043399).
Subject(s)
Diabetic Retinopathy , Fluorescein Angiography , Macula Lutea , Tomography, Optical Coherence , Visual Acuity , Visual Field Tests , Vitrectomy , Humans , Diabetic Retinopathy/physiopathology , Diabetic Retinopathy/surgery , Diabetic Retinopathy/diagnosis , Vitrectomy/methods , Male , Female , Tomography, Optical Coherence/methods , Visual Acuity/physiology , Middle Aged , Visual Field Tests/methods , Fluorescein Angiography/methods , Macula Lutea/blood supply , Macula Lutea/diagnostic imaging , Aged , Adult , Visual Fields/physiology , Retinal Vessels/physiopathology , Retinal Vessels/diagnostic imaging , Postoperative PeriodABSTRACT
BACKGROUND: We aimed to investigate the anatomical features of optical coherence tomography (OCT) and vitreous cytokine levels as predictors of outcomes of combined phacovitrectomy with intravitreal dexamethasone (DEX) implants for idiopathic epiretinal membrane (iERM) treatment. METHODS: A prospective, single-masked, randomized, controlled clinical trial included 48 eyes. They were randomly assigned in a 1:1 ratio to undergo the DEX group (combined phacovitrectomy with ERM peeling and Ozurdex implantation) and control group (phacovitrectomy only). Best-corrected visual acuity (BCVA) and central macular thickness (CMT) were assessed at 1 d, 1 week, 1 month, and 3 months. The structural features of OCT before surgery were analysed for stratified analysis. Baseline soluble CD14 (sCD14) and sCD163 levels in the vitreous fluid were measured using ELISA. RESULTS: BCVA and CMT were not significantly different in the DEX and control groups. Eyes with hyperreflective foci (HRF) at baseline achieved better BCVA (Ptime*group=0.746; Pgroup=0.043, Wald χ²=7.869) and lower CMT (Ptime*group = 0.079; Pgroup = 0.001, Wald χ²=6.774) responses to DEX during follow-up. In all patients, the mean vitreous level of sCD163 in eyes with HRF was significantly higher than that in eyes without HRF (P = 0.036, Z=-2.093) at baseline. In the DEX group, higher sCD163 predicted greater reduction in CMT from baseline to 1 month (r = 0.470, P = 0.049). CONCLUSIONS: We found that intraoperative DEX implantation did not have beneficial effects on BCVA and CMT over a 3-month period in all patients with iERM, implying that the use of DEX for all iERM is not recommended. In contrast, for those with HRF on OCT responded better to DEX implants at the 3-month follow-up and thier vitreous fluid expressed higher levels of sCD163 at baseline. These data support the hypothesis that DEX implants may be particularly effective in treating cases where ERM is secondary to inflammation. TRIAL REGISTRATION: The trail has been registered at Chinese Clinical Trail Registry( https://www.chictr.org.cn ) on 2021/03/12 (ChiCTR2100044228). And all patients in the article were enrolled after registration.
Subject(s)
Biomarkers , Dexamethasone , Aged , Female , Humans , Male , Middle Aged , Biomarkers/metabolism , Dexamethasone/administration & dosage , Dexamethasone/therapeutic use , Drug Implants , Epiretinal Membrane/surgery , Epiretinal Membrane/metabolism , Glucocorticoids/administration & dosage , Glucocorticoids/therapeutic use , Intravitreal Injections , Phacoemulsification , Prospective Studies , Single-Blind Method , Tomography, Optical Coherence/methods , Visual Acuity , Vitrectomy/methods , Vitreous Body/metabolism , Vitreous Body/diagnostic imagingABSTRACT
Chiral epichlorohydrin (ECH) is an attractive intermediate for chiral pharmaceuticals and chemicals preparation. The asymmetric synthesis of chiral ECH using 1,3-dicholoro-2-propanol (1,3-DCP) catalyzed by a haloalcohol dehalogenase (HHDH) was considered as a feasible approach. However, the reverse ring opening reaction caused low optical purity of chiral ECH, thus severely restricts the industrial application of HHDHs. In the present study, a novel selective conformation adjustment strategy was developed with an engineered HheCPS to regulate the kinetic parameters of the forward and reverse reactions, based on site saturation mutation and molecular simulation analysis. The HheCPS mutant E85P was constructed with a markable change in the conformation of (S)-ECH in the substrate pocket and a slight impact on the interaction between 1,3-DCP and the enzyme, which resulted in the kinetic deceleration of the reverse reactions. Compared with HheCPS, the catalytic efficiency (kcat(S)-ECH/Km(S)-ECH) of the reversed reaction dropped to 0.23-fold (from 0.13 to 0.03 mM-1 s-1), while the catalytic efficiency (kcat(1,3-DCP)/Km(1,3-DCP)) of the forward reaction only reduced from 0.83 to 0.71 mM-1 s-1. With 40 mM 1,3-DCP as substrate, HheCPS E85P catalyzed the synthesis of (S)-ECH with the yield up to 55.35% and the e.e. increased from 92.54 to >99%. Our work provided an effective approach for understanding the stereoselective catalytic mechanism as well as the green manufacturing of chiral epoxides.
Subject(s)
Epichlorohydrin , Hydrolases , Epichlorohydrin/chemistry , Epichlorohydrin/metabolism , Hydrolases/genetics , Hydrolases/metabolism , Hydrolases/chemistry , Kinetics , Stereoisomerism , Escherichia coli/genetics , Escherichia coli/enzymology , Protein Engineering/methods , alpha-Chlorohydrin/analogs & derivativesABSTRACT
Objective: The objective of this study was to evaluate the effects of comfort care on perioperative outcomes and postoperative recovery of breast cancer patients. Evaluating comfort care is important in the context of breast cancer surgery because it can potentially alleviate pain, improve patient comfort, enhance postoperative recovery, and reduce complications, ultimately leading to better patient outcomes. Methods: Between March 2020 and December 2021, 78 patients undergoing breast cancer surgery at our hospital were randomly assigned to receive either routine nursing (routine group) or comfort care (experimental group). The comfort care intervention included various components such as health education, preoperative care, intraoperative care, postoperative care, pain care, and psychological care. The routine group received standard nursing care following medical advice. Results: The patient characteristics between the two groups were comparable. Comfort care resulted in significantly higher visual analog scale (VAS) scores, indicating reduced pain, and better improvement in functional recovery of the upper limb compared to routine nursing. Comfort care was also associated with better postoperative recovery, as evidenced by lower self-rating depression scale (SDS) and self-rating anxiety scale (SAS) scores. The experimental group had a significantly lower incidence of complications compared to the routine group. Additionally, the experimental group reported better 24-hour comfort and higher nursing satisfaction. Conclusion: In conclusion, comfort care effectively reduces postoperative pain, promotes postoperative recovery, improves patient emotions, lowers the incidence of complications, and enhances comfort and care satisfaction in breast cancer patients undergoing radical surgery. These findings highlight the importance of incorporating comfort care interventions in the perioperative management of breast cancer patients. Further research and implementation of comfort care strategies may have implications for improving clinical practice and patient outcomes in the future.
ABSTRACT
The Astragalus mongholicus Bunge and Panax notoginseng formula (A&P) has been clinically shown to effectively slow down the progression of chronic kidney disease (CKD) and has demonstrated significant anti-fibrosis effects in experimental CKD model. However, the specific active ingredients and underlying mechanism are still unclear. The active ingredients of A&P were analyzed by Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-HR-MS). A mouse model of CKD was constructed by 5/6 nephrectomy. Renal function was assessed by creatinine and urea nitrogen. Real-time PCR and Western Blot were performed to detect the mRNA and protein changes in kidney and cells. An in vitro fibrotic cell model was constructed by TGF-ß induction in TCMK-1 cells. The results showed that thirteen active ingredients of A&P were identified by UPLC-HR-MS, nine of which were identified by analysis with standards, among which the relative percentage of NOB was high. We found that NOB treatment significantly improved renal function, pathological damage and reduced the expression level of fibrotic factors in CKD mice. The results also demonstrated that Lgals1 was overexpressed in the interstitial kidney of CKD mice, and NOB treatment significantly reduced its expression level, while inhibiting PI3K and AKT phosphorylation. Interestingly, overexpression of Lgals1 significantly increased fibrosis in TCMK1 cells and upregulated the activity of PI3K and AKT, which were strongly inhibited by NOB treatment. NOB is one of the main active components of A&P. The molecular mechanism by which NOB ameliorates renal fibrosis in CKD may be through the inhibition of Lgals1/PI3K/AKT signaling pathway.
Subject(s)
Disease Models, Animal , Drugs, Chinese Herbal , Fibrosis , Flavones , Kidney , Panax notoginseng , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Renal Insufficiency, Chronic , Signal Transduction , Animals , Mice , Renal Insufficiency, Chronic/drug therapy , Renal Insufficiency, Chronic/metabolism , Signal Transduction/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Male , Panax notoginseng/chemistry , Flavones/pharmacology , Flavones/therapeutic use , Kidney/pathology , Kidney/drug effects , Astragalus Plant/chemistry , Mice, Inbred C57BL , Tandem Mass Spectrometry , Chromatography, High Pressure LiquidABSTRACT
Eutrophication is a growing environmental concern in lake ecosystems globally, significantly impacting the structures and ecological functions of bacterioplankton communities and posing a substantial threat to the stability of lake ecosystems. However, the patterns of functional dissimilarity, network complexity, and stability within bacterioplankton communities across different trophic states, along with the underlying mechanisms through which eutrophication influences these aspects, are not well-understood. To bridge this knowledge gap, we collected 88 samples from 34 lakes spanning trophic gradients and investigated bacterioplankton communities using network analysis and multiple statistical methods. Our results reveal that eutrophication, progressing from mesotrophic to hyper-eutrophic states, reduces the putative functional dissimilarity of bacterioplankton, particularly affecting the relative proportions of functional groups such as oxygenic photoautotrophy, phototrophy, and photoautotrophy. Network complexity exhibited a unimodal pattern across increasing trophic states, peaking at mesotrophic states and then decreasing towards hyper-eutrophic conditions, while stability exhibited the opposite pattern (U-shaped), indicating a variation in response to trophic state changes. In essence, eutrophication diminishes network complexity but enhances network stability. Collectively, these findings shed light on the ecological impact of eutrophication on bacterioplankton communities and elucidate the potential mechanisms by which eutrophication drives functional dissimilarity, network complexity and stability within bacterioplankton communities. These insights carry significant implications for the ecological management of eutrophic lakes.
Subject(s)
Ecosystem , Lakes , Lakes/chemistry , Eutrophication , Aquatic Organisms , ChinaABSTRACT
Alzheimer's disease (AD) is a severe threat to human health and one of the three major causes of human death.Double-stranded RNA-dependent protein kinase (PKR) is an interferon-induced protein kinase involved in innate immunity.In the occurrence and development of AD,PKR is upregulated and continuously activated.On the one hand,the activation of PKR triggers an integrated stress response in brain cells.On the other hand,it indirectly upregulates the expression of ß-site amyloid precursor protein cleaving enzyme 1 and facilitates the accumulation of amyloid-ß protein (Aß),which could activate PKR activator to further activate PKR,thus forming a sustained accumulation cycle of Aß.In addition,PKR can promote Tau phosphorylation,thereby reducing microtubule stability in nerve cells.Inflammation in brain tissue,neurotoxicity resulted from Aß accumulation,and disruption of microtubule stability led to the progression of AD and the declines of memory and cognitive function.Therefore,PKR is a key molecule in the development and progression of AD.Effective PKR detection can aid in the diagnosis and prediction of AD progression and provide opportunities for clinical treatment.The inhibitors targeting PKR are expected to control the activity of PKR,thereby controlling the progression of AD.Therefore,PKR could be a target for the development of therapeutic drugs for AD.
Subject(s)
Alzheimer Disease , eIF-2 Kinase , Alzheimer Disease/metabolism , Humans , eIF-2 Kinase/metabolism , Amyloid beta-Peptides/metabolism , tau Proteins/metabolism , Phosphorylation , Brain/metabolism , Amyloid beta-Protein Precursor/metabolismABSTRACT
InGaN quantum dots (QDs) are regarded as a compelling candidate material for the fabrication of high-quality GaN-based micro-LEDs. In this work, to study the impact of a substrate structure on InGaN QDs and QD-based micro-LEDs, GaN-on-sapphire substrates with off-cut angles toward the a-axis of 0.2°, 0.4°, and 0.7° were utilized as templates for the fabrication of InGaN QDs and InGaN QDs-based micro-LEDs. Experimental results show that GaN template with 0.4° off-cut angle exhibits the narrowest terrace width and enables InGaN QDs to be higher and more uniform. The InGaN QD sample grown on 0.4° substrate has a very small wavelength shift of 2.5â nm with temperature increasing and owns the longest photoluminescence peak wavelength implying the highest In content. Furthermore, electroluminescence (EL) spectra demonstrate that QD-based micro-LED array has excellent wavelength stability under various injection currents, and the stability can be improved further on a GaN template with narrower terraces. The results indicate that altering the terrace width of GaN template is a feasible scheme for improving the properties of GaN-based micro-LEDs.