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1.
Molecules ; 27(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35566234

RESUMO

The spodium-π bonding between MX2 (M = Zn, Cd, and Hg; X = Cl, Br, and I) acting as a Lewis acid, and C2H2/C2H4 acting as a Lewis base was studied by ab initio calculations. Two types of structures of cross (T) and parallel (P) forms are obtained. For the T form, the X-M-X axis adopts a cross configuration with the molecular axis of C≡C or C=C, but both of them are parallel in the P form. NCI, AIM, and electron density shifts analyses further, indicating that the spodium-π bonding exists in the binary complexes. Spodium-π bonding exhibits a partially covalent nature characterized with a negative energy density and large interaction energy. With the increase of electronegativity of the substituents on the Lewis acid or its decrease in the Lewis base, the interaction energies increase and vice versa. The spodium-π interaction is dominated by electrostatic interaction in most complexes, whereas dispersion and electrostatic energies are responsible for the stability of the MX2⋯C2F2 complexes. The spodium-π bonding further complements the concept of the spodium bond and provides a wider range of research on the adjustment of the strength of spodium bond.

2.
3 Biotech ; 12(6): 126, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35573802

RESUMO

Salmonella enteritidis is an important food-borne pathogen. The use of antibiotics is a serious threat to animal and human health, owing to the existence of resistant strains and drug residues. Lactic acid bacteria, as a new alternative to antibiotics, has attracted much attention. In this study, we investigated the antibacterial potential and underlying mechanism of Lactobacillus rhamnosus SQ511 against S. enteritidis ATCC13076. The results revealed that L. rhamnosus SQ511 significantly inhibited S. enteritidis ATCC13076 growth or even caused death. Laser confocal microscopic imaging revealed that the cell-free supernatant (CFS) of L. rhamnosus SQ511 elevated the reactive oxygen species level and bacterial membrane depolarization in S. enteritidis ATCC13076, leading to cell death. Furthermore, L. rhamnosus SQ511 CFS had severely deleterious effects on S. enteritidis ATCC13076, causing membrane destruction and the release of cellular materials. In addition, L. rhamnosus SQ511 CFS significantly reduced the expression of virulence, motility, adhesion, and invasion genes in S. enteritidis ATCC13076 (P < 0.05), and considerably inhibited motility and biofilm formation capacity (P < 0.05). Thus, antimicrobial compounds produced by L. rhamnosus SQ511 strongly inhibited S. enteritidis growth, mobility, biofilm formation, membrane disruption, and reactive oxygen species generation, and regulated virulence-related gene expressions, presenting promising applications as a probiotic agent.

3.
Cancer Med ; 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35546443

RESUMO

BACKGROUND: The prognostic significance of insulin-like growth factor binding protein 2 (IGFBP2) expression has been explored in plenty of studies in human cancers. Because of the controversial results, the meta-analysis was carried out to evaluate the relevance of IGFBP2 expression with the prognosis in various tumors. METHODS: The data searched from four databases (Pubmed, Embase, Cochrane library, and Web of science) was used to calculate pooled hazard ratios (HRs) in this meta-analysis. Subgroup analyses were stratified by ethnicity, cancer type, publication year, Newcastle-Ottawa Scale score, treatments, and populations. RESULTS: Twenty-one studies containing 5560 patients finally met inclusion criteria. IGFBP2 expression was associated with lower overall survival (HR = 1.57, 95% CI = 1.31-1.88) and progression-free survival (HR = 1.18, 95% CI = 1.04-1.34) in cancer patients, but not with disease-free survival (HR = 1.50, 95% CI = 0.91-2.46) or recurrence-free survival (HR = 1.50, 95% CI = 0.93-2.40). The subgroup analyses indicated IGFBP2 overexpression was significantly correlated with overall survival in Asian patients (HR = 1.42, 95% CI = 1.18-1.72), Caucasian patients (HR = 2.20, 95% CI = 1.31-3.70), glioma (HR = 1.36, 95% CI = 1.03-1.79), and colorectal cancer (HR = 2.52, 95% CI = 1.43-4.44) and surgery subgroups (HR = 1.97, 95% CI = 1.50-2.58). CONCLUSION: The meta-analysis showed that IGFBP2 expression was associated with worse prognosis in several tumors, and may serve as a potential prognostic biomarker in cancer patients.

4.
Surg Today ; 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35546641

RESUMO

PURPOSE: We introduced a novel colorectal anastomotic technique, double-angle anastomosis combined with the double stapling technique (DAA-DST), to simplify the anastomosis step during natural orifice specimen extraction surgery (NOSES) and compared its safety and effectiveness with purse string anastomosis combined with the double stapling technique (PSA-DST). METHODS: Between January 2018 and March 2021, 63 patients with colorectal cancer underwent NOSES with DAA-DST or PSA-DST. We compared the perioperative and oncological outcomes between the groups. RESULTS: There were no significant differences in the operation time, blood loss, time to first passage of flatus and excrement or hospital stay duration between PSA-DST and DAA-DST groups. The overall postoperative complication rates were similar (DAA-DST vs PSA-DST, 21.2% vs 26.7%, p = 0.78), including the rate of anastomotic leakage (6.1% vs 10%, p = 0.91). The rate of successful DAA-DST was higher than that of PSA-DST (100% vs 93.3%). The DAA-DST group had a lower rate of positive drain fluid culture than the PSA-DST group (18.2% vs 26.7% p = 0.61). Recurrence (3.01% vs 6.67%, p = 0.93) and metastasis rates (6.06% vs 6.67%, p = 0.98) were similar between the groups. CONCLUSION: DAA-DST is a safe and effective procedure and can simplify the procedure of NOSES.

5.
Cell Biol Toxicol ; 2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35567596

RESUMO

Circular RNAs (circRNAs) have been extensively studied in tumor development and treatment. CircZNF609 (hsa_circ_0000615) has been shown to serve as an oncogene in all kinds of solid tumors and may act as the novel biomarker in tumor diagnosis and therapy in tumor early diagnosis and therapy. However, the underlying character and mechanism of circZNF609 in cisplatin chemosensitivity and bladder cancer (BCa) development were unknown. The expression level of cell division cycle 25B (CDC25B), microRNA 1200 (miR-1200), and circZNF609 in BCa cells and tissues depended on quantitative real-time PCR (qRT-PCR). CDC25B protein level was assayed with Western blot. Functional assays in vitro and in vivo had been conducted to inspect the important role of circZNF609 on BCa progression and cisplatin chemosensitivity in BCa. RNA sequencing and online databases were used to predict the interactions among circZNF609, miR-1200, and CDC25B. Mechanistic exploration was confirmed by RNA pull-down assay, RNA fluorescence in situ hybridization (FISH) and Dual luciferase reporter assay. CircZNF609 expression was increased significantly in BCa cell lines and tissues. For BCa patients, increased expression of circZNF609 was correlated with a worse survival. In vitro and in vivo, enforced expression of circZNF609 enhanced BCa cells proliferation, migration, and cisplatin chemoresistance. Mechanistically, circZNF609 alleviated the inhibition effect on target CDC25B expression by sponging miR-1200. CircZNF609 promoted tumor growth through novel circZNF609/miR-1200/CDC25B axis, implying that circZNF609 has significant potential to act as a new diagnostic biomarker and therapeutic target in BCa. Enhancing cisplatin sensitivity is an important direction for bladder cancer management. 1. This research reveals that circZNF609 improves bladder cancer progression and inhibits cisplatin sensitivity by inducing G1/S cell cycle arrest via a novel miR-1200/CDC25B cascades. 2. CircZNF609 was confirmed associated with worse survival of bladder cancer patients. 3. CircZNF609 act as a prognostic biomarker for bladder cancer treatment.

6.
Inorg Chem ; 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35588277

RESUMO

A rare 3D Indium-containing polyoxoniobate framework {H9[Cu(en)2(H2O)2][Cu(en)2]12[In(en)]5[Nb23-O65(OH)3(H2O)2]{Nb24O67(OH)2(H2O)3]2}·68H2O(1), based on the In-containing polyoxoniobate cluster, {[In(en)]5[Nb23O65(OH)3(H2O)2][Nb24O67(OH)2(H2O)3]2}35- ({In5Nb71}) and [Cu(en)2]2+ linkers has been successfully synthesized. The nest-like cluster {In5Nb71} is constructed from one brand-new V-shaped {Nb23O70}, two triangle-shaped {Nb24O72} and five [In(en)]3+. The [In(en)] fragments link {Nb24O72} and {Nb23O70} units into unique {In5Nb71}n helical pillars. The copper-amine complexes connect the {In5Nb71}n helical pillars into a three-dimensional (3D) inorganic-organic hybrid In-Cu-containing framework. This material also exhibits good ionic conductivity and vapor adsorption capacity properties.

7.
Zhongguo Gu Shang ; 35(5): 423-9, 2022 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-35535529

RESUMO

OBJECTIVE: To investigate the effects of different bone cement morphology distribution on the clinical efficacy of unilateral percutaneous vertebroplasty(PVP) for spinal osteoporotic fractures. METHODS: The clinical data of 66 patients with osteoporotic vertebral compression fractures received unilateral PVP treatment from January 2019 to April 2020 were retrospectively analyzed. There were 16 males and 50 females, including 83 vertebral bodies, 45 thoracic vertebrae and 38 lumbar vertebrae, and 55 patients with single-segment, 6 double-segment, 4 three-segment and 1 four-segment. The age ranged from 60 to 93 years with an average of (76.83±8.65) years. The included patients were admitted to hospital 1 to 10 days after onset, and were diagnosed by anteroposterior and lateral X-rays, MRI and bone density examination before surgery. According to the shape of bone cement in postoperative X-ray, the patients were divided into O-shaped group (28 cases) and H-shaped group (38 cases). In O-shaped group, the bone cement presented agglomeration mass distribution in the affected vertebra in postoperative X-ray while the bone cement presented disseminated honeycomb distribution in the affected vertebrae in H-shaped group. Bone cement injection volume was collected in two groups. The intraoperative bone cement leakage and postoperative adjacent vertebral fractures were observed. The VAS of the two groups before operation and 1 day, 1 month, 6 months and 1 year after operation were compared;and ODI of the two groups 1 day, 6 months and 1 year after operation were compared. The kyphosis angle and anterior height of the affected vertebrae were measured before operation and 1 week, 1 year after operation. RESULTS: All 66 patients completed 1-year follow-up, and all patients healed well at the puncture site after surgery. There were 1 case and 8 cases of bone cement leakage in O-shaped group and H-shaped group during surgery respectively (P<0.05), but no serious complications occurred. One case occurred adjacent vertebral fracture in both groups during one-year follow-up (P>0.05). There was no statistical significance in injection amount of bone cement between the two groups (P>0.05). The VAS scores of O-shaped group and H-shaped group were 7.89±0.79, 2.75±1.08, 0.46±0.58, 0.36±0.49 and 8.00±1.04, 2.58±1.15, 0.53±0.56, 0.42±0.50 before operation, 1 day, 6 months, 1 year after operation respectively, and there was no statistical significance(P>0.05), and the VAS scores were 0.96±0.58 and 1.18±0.83 at 1 month after operation respectively, with statistical significance(P<0.05). The ODI scores of O-shaped group and H-shaped group were 12.43±3.78, 10.00±2.46, 8.43±1.50 and 12.11±3.68, 9.53±2.35, 8.32±1.51 at 1 day, 6 months and 1 year after surgery respectively, and there was no statistical significance between the two groups(P>0.05). There were no statistical significance in kyphotic angles and anterior height before surgery and 1 week, 1 year after surgery between two groups (P>0.05). CONCLUSION: No matter the distribution of bone cement is O-shape or H-shape, it can achieve good clinical effect, and the prognosis effect is equivalent. Therefore, when performing unilateral puncture PVP surgery, it is not necessary to deliberately increase the puncture angle of the puncture needle in order to achieve the full diffusion of the affected vertebrae, so as to reduce the risk of damaging important structures and bone cement leakage.


Assuntos
Fraturas por Compressão , Cifose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Vertebroplastia , Idoso , Idoso de 80 Anos ou mais , Cimentos Ósseos/uso terapêutico , Feminino , Fraturas por Compressão/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/cirurgia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Punção Espinal , Resultado do Tratamento
8.
Plant Commun ; : 100309, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35605201

RESUMO

Green petals pose a challenge for pollinators to distinguish flowers from leaves, but they are valuable as a specialty flower trait. However, little is understood about the molecular mechanisms that underlie the development of green petals. Here, we report that CINCINNATA (CIN)-like TEOSINTE BRANCHED 1/CYCLOIDEA/PCF (TCP) proteins play key roles in the control of petal color. The septuple tcp2/3/4/5/10/13/17 mutant produced flowers with green petals due to chlorophyll accumulation. Expression of TCP4 complemented the petal phenotype of tcp2/3/4/5/10/13/17. We found that chloroplasts were converted into leucoplasts in the distal parts of wild-type petals but not in the proximal parts during flower development, whereas plastid conversion was compromised in the distal parts of tcp2/3/4/5/10/13/17 petals. TCP4 and most CIN-like TCPs were predominantly expressed in distal petal regions, consistent with the green-white pattern in wild-type petals and the petal greening observed in the distal parts of tcp2/3/4/5/10/13/17 petals. RNA-sequencing data revealed that most chlorophyll biosynthesis genes were downregulated in the white distal parts of wild-type petals, but these genes had elevated expression in the distal green parts of tcp2/3/4/5/10/13/17 petals and the green proximal parts of wild-type petals. We revealed that TCP4 repressed chlorophyll biosynthesis by directly binding to the promoters of PROTOCHLOROPHYLLIDE REDUCTASE (PORB), DIVINYL REDUCTASE (DVR), and SUPPRESSOR OF OVEREXPRESSION OF CO 1 (SOC1), which are known to promote petal greening. We found that the conversion of chloroplasts to leucoplasts and the green coloration in the proximal parts of petals appeared to be conserved among plant species. Our findings uncover a major molecular mechanism that underpins the formation of petal color patterns and provide a foundation for the breeding of plants with green flowers.

9.
Exp Cell Res ; : 113216, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35605648

RESUMO

Missed abortion (MA) is a special form of spontaneous abortion that is increasing in incidence. However, the precise molecular mechanisms underlying MA, especially regarding the decidua, are poorly understood. Herein, we identified molecular signaling pathways related to MA by comparing the decidua of women experiencing normal pregnancy and MA using a quantitative proteomics approach based on HPLC-MS/MS and iTRAQ labeling. Integrated bioinformatics analysis of villi and decidua was performed to reveal potential crosstalk signals in closely related tissues. We identified 2277 proteins with high confidence in decidua, of which 232 were differentially expressed in MA samples. Specifically, we reported that integrated quantitative proteomic and bioinformatic analysis revealed altered proteins in MA and the mechanisms underpinning MA involved numerous pathways, especially ribosome and cellular metabolism signaling. Moreover, Importin 9, Cullin 1 and COX6C are critical for MA, and their altered expression might contribute to the pathophysiology of MA. In particular, COX6C was dramatically down-regulated in both decidua and villi of MA. COX6C was also found to be highly expressed in syncytiotrophoblastic and cytotrophoblastic cells in villi and widely expressed in decidua of the control group, but dramatically decreased in the MA group. Functional analysis showed that knockdown of COX6C inhibited apoptosis process in both HTR-8 and SiHa cells, suggesting that COX6C may play protective effects in MA. Thus, this study could help to map the regulatory protein network related to MA and contribute to the pathophysiological mechanisms of MA.

10.
Front Public Health ; 10: 881074, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35602144

RESUMO

Background: Smartphone-based online education gained popularity during and after the COVID-19 pandemic. Although recent studies have highlighted the association between problematic smartphone use (PSU) and mental health symptoms, the potential role of online learning in this relationship remains unclear. This study aimed to analyze the relationships between higher education modes, PSU, and related psychological symptoms in university students. Methods: A total of 1,629 Chinese university students from five provinces completed a web-based questionnaire survey between March 2020 and October 2021. Demographic characteristics and learning conditions were recorded. All participants completed the Smartphone Addiction Scale-Short Version, Patient Health Questionnaire, Generalized Anxiety Disorder Scale, and Athens Insomnia Scale. Multiple regressions models and stratified analyses were used to examine the association between online education mode, PSU, and symptoms of depression, anxiety, and insomnia. Results: The prevalence of PSU was 58.5%. Students who relied primarily on online learning had a higher prevalence of depressive symptoms (29.95% vs. 22.24%), anxiety symptoms (25.13% vs. 18.91%), and insomnia symptoms (75.89% vs. 70.27%) than those who relied on traditional face-to-face learning (Ps < 0.05). After adjusting for covariates, subjects with PSU were more likely to report depressive symptoms (AdjOR = 3.14, 95% CI = 2.26-4.37), anxiety symptoms (AdjOR = 3.73, 95% CI = 2.13-4.59), and insomnia symptoms (AdjOR = 2.96, 95% CI = 2.23-3.92) than those without PSU. Furthermore, the associations of PSU with depressive symptoms (OR = 4.66 vs. 2.33, P for interaction = 0.015) and anxiety symptoms (OR = 6.05 vs. 2.94, P for interaction = 0.021) were more pronounced in the online learning group. Conclusion: Our study provides preliminary evidence that Chinese university students have serious smartphone addiction problems, which are associated with depressive, anxiety, and insomnia symptoms. Online learning is found to exacerbate PSU and mental health problems. Our findings provide valuable information for targeted psychological interventions in the post-COVID-19 era.


Assuntos
COVID-19 , Educação à Distância , Distúrbios do Início e da Manutenção do Sono , COVID-19/epidemiologia , China/epidemiologia , Humanos , Transtorno de Adição à Internet/epidemiologia , Pandemias , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Estudantes/psicologia
11.
Stem Cell Res ; 62: 102808, 2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35569347

RESUMO

To achieve efficient, reproducible differentiation of human pluripotent stem cells (hPSCs) towards specific hematopoietic cell-types, a comprehensive understanding of the necessary cell signaling and developmental trajectories involved is required. Previous studies have identified the mesodermal progenitors of extra-embryonic-like and intra-embryonic-like hemogenic endothelium (HE), via stage-specific WNT and ACTIVIN/NODAL, with GYPA/GYPB (CD235a/b) expression serving as a positive selection marker for mesoderm harboring exclusively extra-embryonic-like hemogenic potential. However, a positive mesodermal cell-surface marker with exclusively intra-embryonic-like hemogenic potential has not been identified. Recently, we reported that early mesodermal expression of CDX4 critically regulates definitive HE specification, suggesting that CDX4 may act in a cell-autonomous manner during hematopoietic development. To identify CDX4+ mesoderm, we performed single cell (sc)RNAseq on hPSC-derived mesodermal cultures, revealing CDX4hi expressing mesodermal populations were uniquely enriched in the non-classical MHC-Class-1 receptor CD1D. Flow cytometry demonstrated approximately 60% of KDR+CD34-CD235a- mesoderm was CD1d+, and CDX4 was robustly enriched within CD1d+ mesoderm. Critically, only CD1d+ mesoderm harbored CD34+ HOXA+ HE with multilineage erythroid-myeloid-lymphoid potential. Thus, CDX4+CD1d+ expression within early mesoderm demarcates an early progenitor of HE. These insights may be used for further study of human hematopoietic development and improve hematopoietic differentiation conditions for regenerative medicine applications.

12.
Int J Pharm ; 620: 121738, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35427744

RESUMO

The purpose of this study was to investigate the self-sensitization of photosensitizer without an external light source to produce a photodynamic therapy (PDT) effect based on the principle of bioluminescence resonance energy transfer (PDT-BRET). First, we demonstrated that HeLa cells could efficiently express firefly luciferase (FLase) after the firefly luciferase gene was transfected with the FLase-gene plasmid (FLase-GP), and proved that FLase could act on the substrate firefly D-luciferin (FLuc) to produce photons. The generated photons activate the photosensitizer hypericin (Hyp) and induce cytotoxicity. Then, we successfully prepared carboxymethyl chitosan-modified poly(lactic-co-glycolic acid) nanoparticles (CPNPs) loaded with FLuc (FLuc-CPNPs) and with loaded Hyp (Hyp-CPNPs). Their physicochemical and pharmaceutical characteristics indicated that they were an excellent drug delivery system. Characterization of the biological effects showed that they could be located in the mitochondrial, had higher ROS generation and stronger cytotoxicity. In vivo results also showed that PDT-BRET was as effective as classic PDT. PDT-BRET and the related drug delivery system are expected to become a new platform for anticancer therapy.

13.
Zootaxa ; 5094(4): 587-594, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35391434

RESUMO

A new species belonging to the kinabaluensis group of the trachelid genus Utivarachna Kishida, 1940, U. fanjing sp. nov., is described from southwestern China. Detailed description, diagnosis, photographs and distribution map of the new species are given. DNA barcodes (a partial fragment of the mitochondrial cytochrome oxidase subunit I gene, COI) of the species were obtained to confirm matching of the sexes and for future use in molecular studies.


Assuntos
Aranhas , Animais , Tamanho Corporal , China , Genes Mitocondriais , Tamanho do Órgão , Aranhas/genética
14.
Front Immunol ; 13: 847263, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371059

RESUMO

Several studies have demonstrated that the T-cell receptor (TCR) repertoire is associated with prognosis and immune therapy response in several types of cancer. However, the comprehensive features of TCR repertoire in tumor-infiltrating and circulating T cells, as well as its clinical significance of diagnosis in hepatocellular carcinoma (HCC) patients, are still unknown. In this study, we perform paired tumor/peritumoral tissues and peripheral blood samples from 58 patients with HCC and sequenced them with high-throughput TCR to comprehensively analyze the characteristics of TCR and the clinical significance of peripheral TCR sequence. By exploring the abundance and diversity of TCR repertoires, we observe that there was a significantly higher TCR diversity in peripheral blood than in tumoral and peritumoral tissues, while tumoral and peritumoral tissues showed similar TCR diversity. A substantial difference in the usage frequencies of several Vß, Jß genes, and TCRß VJ pairings was found among three types of tissues. Moreover, we reveal that HCC patients have a unique profile of TCR repertoire in peripheral blood in contrast to healthy individuals. We further establish an HCC diagnostic model based on TCRß VJ pairing usage in peripheral blood, which yields a best-fit area under the curve (AUC) of 0.9746 ± 0.0481 (sensitivity = 0.9675 ± 0.0603, specificity = 0.9998 ± 0.0007, average of 100 repeats) in the test set. Our study describes the characteristics of tissue infiltration and circulating T-cell bank in patients with HCC and shows the potential of using circulating TCR sequence as a biomarker for the non-invasive diagnosis of patients with HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/genética , Humanos , Neoplasias Hepáticas/genética , Prognóstico , Receptores de Antígenos de Linfócitos T , Linfócitos T
15.
J Nat Prod ; 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35427111

RESUMO

As a plant used in both food and medicine, Sauropus spatulifolius is consumed widely as a natural herbal tea, food source, and Chinese medicine. Inspired by its extensive applications, we conducted a systematic phytochemical study of the leaves of S. spatulifolius. Thirteen new diterpenoids, sauspatulifols A-M (1-13), including four ent-cleistanthane-type diterpenoids (1-4), eight 15,16-di-nor-ent-cleistanthane-type diterpenoids (5-12), and one 17-nor-ent-pimarane-type diterpenoid (13) as well as one known diterpenoid, cleistanthol (14), were isolated. All of these diterpenoids feature a 2α,3α-dihydroxy unit within the A ring, and their structures were elucidated by spectroscopic data analysis, electronic circular dichroism calculations, and single-crystal X-ray diffraction analysis. Compound 14 displayed moderate inhibitory activity against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, and Shigella flexneri with the same minimum inhibitory concentration value of 12 µg/mL as well as activity against vesicular stomatitis virus and influenza A virus.

16.
Plant Cell ; 2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35435232

RESUMO

Glycogen synthase kinase 3 (GSK3) family members serve as signaling hubs for plant development and stress responses, yet the underlying mechanism of their transcriptional regulation remains a long-standing mystery. Here we show that the transcription of SHAGGY-like kinase 11/12 (SK11/12), two members of the GSK3 gene family, is promoted by the splicing factor SmD1b, which is essential for distributing carbon sources into storage and protective components in Arabidopsis seeds. The chromatin recruitment of SmD1b at the SK11/12 loci promotes their transcription associated with co-transcriptional splicing of the first introns in the 5' untranslated region of SK11/12. The loss of SmD1b function generates transcripts with unspliced introns that create disruptive R-loops to hamper the transcriptional elongation of SK11/12, in addition to compromising the recruitment of RNA polymerase II to the SK11/12 genomic regions. These effects imposed by SmD1b determine the transcription of SK11/12 to confer a key switch of carbon flow among metabolic pathways in zygotic and maternal tissues in seeds.

17.
Curr Med Sci ; 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35451808

RESUMO

OBJECTIVE: This study aimed to identify microRNAs (miRNAs) involved in the development of perioperative neurocognitive disorders (PND). METHODS: Plasma exosomal miRNA expression was examined in patients before and after cardiopulmonary bypass (CPB) using microarray and qRT-PCR and these patients were diagnosed as PND later. Elderly rats were subjected to CPB, and the cognitive functions were examined. Bioinformatics analysis was conducted to predict the targets of miR-214-3p. Rats were administered rno-miR-214-3p agomir before or after CPB to investigate the role of miR-214-3p in PND development. RESULTS: We identified 76 differentially expressed plasma exosomal miRNAs in PND patients after surgery (P<0.05, ∣log2FC∣>0.58), including the upregulated hsa-miR-214-3p (P=0.002399392). Prostaglandin-endoperoxide synthase 2 (PTGS2) was predicted as a miR-214-3p target. In rats, CPB reduced the platform crossing numbers and target quadrant stay time, accompanied with hippocampal neuronal necrosis. The rno-miR-214-3p level was significantly increased in plasma exosomes but decreased in rat hippocampus after surgery, exhibiting a negative correlation (P<0.001, r=-0.762). A negative correlation between miR-214-3p and PTGS2 protein expression was also observed in the hippocampus after surgery. Importantly, rno-miR-214-3p agomir treatment, before or after surgery, significantly increased the platform crossing numbers (P=0.035) and target quadrant stay time (P=0.029) compared with negative control. Hippocampal PTGS2 protein level was increased in the untreated surgery group and decreased in response to rno-miR-214-3p agomir treatment before or after surgery (both P<0.05 vs. negative control). CONCLUSION: These data suggest that miR-214-3p/PTGS2 signaling contributes to the development of PND, serving as a potential therapeutic target for PND.

18.
Clin Oral Investig ; 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35441898

RESUMO

OBJECTIVES: This study was designed to explore the effects of mechanical force on the proliferation, apoptosis, and morphology of stem cells from human exfoliated deciduous tooth pulp (SHEDs). MATERIALS AND METHODS: Caries-free stranded deciduous teeth were extracted, and SHEDs were isolated through enzymatic digestion. The cultured SHEDs were subjected to different levels of mechanical stimuli (0, 100, 200, and 300 g) for 7 days (30 min/day) using external centrifugal force. Cell proliferation was evaluated with the CCK-8 assay, and the cell cycle and apoptosis were assessed by flow cytometry. The cell morphology was examined using transmission electron microscopy. RESULTS: Cell proliferation assay showed no differences between the three stimulation groups and the control group in day 1 to day 3. From the 4th day, cell proliferation was significantly lower in the mechanical force groups than in the control group, but no significant difference was observed among the three mechanical force groups. Besides, there was no significant difference in cell apoptosis among the four groups for 7 days. On day 7 after stimulation, the SHEDs were shrunken, with significantly increased isochromosome in the nucleus and an increase in lysosomes. CONCLUSIONS: Mechanical force can inhibit the proliferation and affect morphology of SHEDs, but it has no effect on cell apoptosis. CLINICAL RELEVANCE: Mechanical force stimulation significantly inhibited cell proliferation of SHEDs. Mechanical force stimulation had no significant effect on cell apoptosis of SHEDs. The morphology and ultrastructure of SHEDs changed after mechanical force stimulation.

19.
Artigo em Inglês | MEDLINE | ID: mdl-35460485

RESUMO

In this study, cationic polyacrylamide (CPAM)-modified diatomite and cetyl trimethyl ammonium bromide (CTAB)-modified diatomite were synthesized and used as conditioners for sewage sludge dewatering. The effects of these two types of modified diatomite on the dewaterability and settling performance of the activated sludge were studied. The mechanisms of the two modified diatomite types in the activated sludge system were elucidated. The efficiency of the CPAM-modified diatomite was better than that of the CTAB-modified diatomite in improving the settleability and dewaterability of sludge. The results indicated that specific resistance to filtration (SRF) was decreased from 8.52 × 1012 to 0.92 × 1012 m/Kg, and the water content in the remaining sludge cake after pumping filtration was decreased from 92.2 to 68.1% by adding 0.4% of CPAM-modified diatomite and pH = 3.5, which resulted in excellent sludge settling of activated sludge. Further studies showed that the polymer/surfactant adsorbed in diatomite increased sludge dewaterability and improved the sedimentation rate owing to stripping extracellular polymeric substances (EPS) and damaging the internal structure of the sludge, leading to sludge conduce bound water release. According to scanning electron microscope (SEM) images, the two types of modified diatomite powder maintained the porous structure and showed a more complete and uniform structure compared to natural diatomite.

20.
Nat Commun ; 13(1): 2102, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440635

RESUMO

The development of next-generation organic electronic materials critically relies on understanding structure-function relationships in conjugated polymers. However, unlocking the full potential of organic materials requires access to their vast chemical space while efficiently managing the large synthetic workload to survey new materials. In this work, we use automated synthesis to prepare a library of conjugated oligomers with systematically varied side chain composition followed by single-molecule characterization of charge transport. Our results show that molecular junctions with long alkyl side chains exhibit a concentration-dependent bimodal conductance with an unexpectedly high conductance state that arises due to surface adsorption and backbone planarization, which is supported by a series of control experiments using asymmetric, planarized, and sterically hindered molecules. Density functional theory simulations and experiments using different anchors and alkoxy side chains highlight the role of side chain chemistry on charge transport. Overall, this work opens new avenues for using automated synthesis for the development and understanding of organic electronic materials.


Assuntos
Polímeros , Adsorção , Polímeros/química
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