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1.
Biol Open ; 13(10)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39373150

RESUMO

Maternal inheritance of mitochondrial DNA (mtDNA) is a widespread phenomenon in eukaryotes. Our earlier research indicated that sperm mtDNA is removed prior to fertilization in mice, and Endonuclease G (ENDOG) orchestrates the degradation of sperm mitochondria in Caenorhabditis elegans. However, the mechanisms underlying sperm mtDNA disposal in mammals remain poorly understood. To investigate the potential role of ENDOG in sperm mtDNA elimination, we created Endog knockout (Endog-/-) mice. Our findings revealed that Endog-/- mice maintained normal spermatogenesis and fertility. Most strikingly, we detected no substantial discrepancy in sperm mtDNA copy number between Endog-/- and control mice. Furthermore, we noted that sperm mtDNA copy numbers were unchanged in both less motile and motile sperm isolated by Percoll gradient centrifugation from Endog-/- and control mice. Taken together, our results indicate that ENDOG is not essential for spermatogenesis or the elimination of sperm mtDNA in mice.


Assuntos
DNA Mitocondrial , Endodesoxirribonucleases , Camundongos Knockout , Espermatogênese , Espermatozoides , Animais , Masculino , Espermatogênese/genética , DNA Mitocondrial/genética , Espermatozoides/metabolismo , Camundongos , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/genética , Fertilidade/genética
2.
Complement Ther Med ; : 103103, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39454736

RESUMO

BACKGROUND: Transcutaneous electrical acupoint stimulation (TEAS) may contribute to blood pressure (BP) control, but the evidence remains insufficient. Our objectives were to evaluate the impact of TEAS on hypertension and determine the optimal frequency. METHODS: A total of 120 hypertensive patients were randomly allocated to the TEAS-2Hz group, TEAS-10Hz group, or usual care control group in a 1:1:1 ratio. All patients were advised to continue their usual antihypertensive regimen. Additionally, patients in the TEAS groups received TEAS therapy 3 times per week for 4 weeks, with a 4-week follow-up. RESULTS: The primary outcome was the change in systolic BP (SBP) from baseline to week 4. Secondary outcomes included changes in diastolic BP (DBP), mean arterial pressure (MAP), heart rate (HR), heart rate variability (HRV), and 12-item health survey (SF-12) at different time points. Both TEAS groups showed reductions in SBP relative to control (TEAS-2Hz group vs. control, -4.70mmHg [95% CI, -7.00 to -2.40mmHg]; P < 0.001; TEAS-10Hz group vs. control, -8.66mmHg [95% CI, -10.97 to -6.36mmHg]; P < 0.001). TEAS-10Hz provided a significant decrease in SBP than TEAS-2Hz (-3.96mmHg [95% CI, -1.66 to -6.26mmHg]; P < 0.001). TEAS groups also exhibited reductions in DBP, MAP, HR, LF/HF ratio(LF/HF), very low frequency (VLF), and normalized low frequency (LF norm), and an increase in normalized high frequency (HF norm) than control. No differences were observed among groups in low frequency (LF), high frequency (HF), total power (TP), very low frequency (VLF), and SF-12. CONCLUSION: TEAS might be a promising adjunctive therapy for hypertension, and the recommended frequency is 10Hz, which should be confirmed in larger trials.

3.
JAMA Intern Med ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39401008

RESUMO

Importance: Sciatica is commonly caused by herniated lumbar disc and contributes to severe pain and prolonged disability. Although acupuncture is widely used by patients with chronic sciatica, the evidence of its efficacy is scarce. Objective: To investigate the efficacy and safety of acupuncture compared with sham acupuncture in patients with chronic sciatica from herniated disk. Design, Settings, and Participants: This was a multicenter 2-arm randomized clinical trial conducted in 6 tertiary-level hospitals in China of patients with chronic sciatica from herniated disk. Participants were recruited from March 25, 2021, to September 23, 2021, with a final follow-up through September 22, 2022. Data analyses were performed from December 2022 to March 2023. Interventions: Participants were randomly assigned to receive 10 sessions of acupuncture (n = 110) or sham acupuncture (n = 110) over 4 weeks. Participants, outcome assessors, and statisticians were blinded. Main Outcomes and Measures: The 2 coprimary outcomes were changes in visual analog scale (VAS) for leg pain and Oswestry Disability Index (ODI) from baseline to week 4. Secondary outcomes were adverse events. Results: A total of 216 patients (mean [SD] age, 51.3 [15.2] years; 147 females [68.1%] and 69 males [31.9%]) were included in the analyses. The VAS for leg pain decreased 30.8 mm in the acupuncture group and 14.9 mm in the sham acupuncture group at week 4 (mean difference, -16.0; 95% CI, -21.3 to -10.6; P < .001). The ODI decreased 13.0 points in the acupuncture group and 4.9 points in the sham acupuncture group at week 4 (mean difference, -8.1; 95% CI, -11.1 to -5.1; P < .001). For both VAS and ODI, the between-group difference became apparent starting in week 2 (mean difference, -7.8; 95% CI, -13.0 to -2.5; P = .004 and -5.3; 95% CI, -8.4 to -2.3; P = .001, respectively) and persisted through week 52 (mean difference, -10.8; [95% CI, -16.3 to -5.2; P < .001; and -4.8; 95% CI, -7.8 to -1.7; P = .003, respectively). No serious adverse events occurred. Conclusions and Relevance: This randomized clinical trial found that in patients with chronic sciatica from herniated disk, acupuncture resulted in less pain and better function compared with sham acupuncture at week 4, and these benefits persisted through week 52. Acupuncture should be considered as a potential treatment option for patients with chronic sciatica from a herniated disk. Trial Registration: Chictr.org Identifier: ChiCTR2100044585.

4.
World J Hepatol ; 16(10): 1188-1198, 2024 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-39474574

RESUMO

BACKGROUND: Complement activation is recognized as an important factor in the progression of liver damage caused by acetaminophen (APAP). However, the role of the complement inhibitor C2-FH in APAP-induced liver injury remains unclear. AIM: To explore C2-FH in protecting against APAP-induced liver injury by inhibiting complement activation. METHODS: A model of APAP-induced liver injury was used to study the protective effect of C2-FH on liver injury. C2-FH was administered through intraperitoneal injection 30 minutes after APAP treatment. We detected the effects of C2-FH on liver function, inflammatory response and complement activation. Additionally, RNA-sequencing (RNA-Seq) analysis was conducted to understand the mechanism through which C2-FH provides protection against APAP-induced liver injury. RESULTS: C2-FH inhibited the increase in serum alanine aminotransferase activity, aspartate aminotransferase activity and lactate dehydrogenase, and reduced liver tissue necrosis caused by APAP. Moreover, it attenuated the inflammatory response and inhibited complement activation in APAP-induced liver injury. RNA-Seq analysis provided additional explanations for the protective role of C2-FH against APAP-induced liver injury. CONCLUSION: C2-FH attenuates APAP-induced liver injury by inhibiting complement activation.

5.
Front Pain Res (Lausanne) ; 5: 1370704, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39385756

RESUMO

Background: There is an urgent need to confirm biomarkers reflecting the pathogenesis and targeted drugs of lower back pain or/and sciatica in clinical practice. This study aimed to conduct a two sample bidirectional Mendelian randomization (MR) analysis to explore the causal link between 486 serum metabolites and lower back pain or/and sciatica. Methods: All data come from two public shared databases of European ancestry and single nucleotide polymorphisms (SNPs) for lower back pain or/and sciatica acted as instrumental variables. The traditional inverse variance weighting (IVW) method, weighted-median method, MR-Egger methodand other methods were used to estimate causality. The horizontal pleiotropy, heterogeneities were also verified through the MR-Egger intercept test, Cochran's Q test, MR-PRESSO test and the leave-one-out sensitivity analysis. Reverse MR analysis was employed to evaluate the direct impact of metabolites on lower back pain or/and sciatica. Additionally, we conducted the colocalization analysis to reflect the causality deeply. Furthermore, metabolic pathway analysis was performed. Results: 28 metabolites (18 known metabolites, 1 identified metabolites and 9 unknown metabolites) relevant to the risk of sciatica or/and lower back pain after using genetic variants as probes at PIVW < 0.05 were identifed. Among them, 8 serum metabolites decreased risk of sciatica or/and lower back pain significantly (P < 0.05), and 14 serum metabolites increased risk of sciatica or/and lower back pain significantly (P < 0.05). No reverse causal association was found between 28 metabolites and sciatica or/and lower back pain. Colocalization analysis results showed that the associations between sciatica or/and lower back pain and the 28 identified metabolites were not due to shared causal variant sites. Moreover, pathway enrichment analysis identifed 11 signifcant metabolic pathways, which are mainly involved in the pathological mechanism of sciatica or/and lower back pain (P < 0.05). There was no horizontal pleiotropy or heterogeneity in the other analyses. Conclusion: Our analyses provided robust evidence of causal associations between blood metabolites on sciatica or/and lower back pain. However, the underlying mechanisms remain to be further investigated.

6.
Nano Lett ; 24(40): 12568-12575, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39315654

RESUMO

The introduction of nitrogen vacancies has been shown to be an effective way to tune the plasmonic properties of refractory titanium nitrides. However, its underlying mechanism remains debated due to the lack of high-quality single-crystalline samples and a deep understanding of electronic properties. Here, a series of epitaxial titanium nitride films with varying nitrogen vacancy concentrations (TiNx) were synthesized. Spectroscopic ellipsometry measurements revealed that the plasmon energy could be tuned from 2.64 eV in stoichiometric TiN to 3.38 eV in substoichiometric TiNx. Our comprehensive analysis of electrical and plasmonic properties showed that both the increased electronic states around the Fermi level and the decreased carrier effective mass due to the modified electronic band structures are responsible for tuning the plasmonic properties of TiNx. Our findings offer a deeper understanding of the tunable plasmonic properties in epitaxial TiNx films and are beneficial for the development of nitride plasmonic devices.

7.
Org Biomol Chem ; 22(40): 8189-8197, 2024 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-39292510

RESUMO

Recently, several studies on the chemical synthesis of brevianamide A (BA) were reported. In particular, a highly efficient and remarkably selective synthetic strategy was reported by Lawrence's group. However, a unified mechanistic understanding of these results is still lacking. We have carried out a DFT study and proposed a unified mechanism to understand these experimental results. Starting from intermediate 2, the most favorable reaction sequence is a fast tautomerization, followed by a σ-migration of the base moiety, and a final inverse-electron demanding Diels-Alder reaction, resulting in the formation of the BA product stereoselectively. This reaction mechanism can also be applied to understand the biosynthesis of BA that involves enzymatic catalysis.


Assuntos
Teoria da Densidade Funcional , Estereoisomerismo , Estrutura Molecular , Biomimética , Materiais Biomiméticos/química , Materiais Biomiméticos/síntese química , Reação de Cicloadição
8.
Org Biomol Chem ; 22(41): 8317-8322, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39311636

RESUMO

Facilitated by an electron donor-acceptor (EDA) complex, an efficient ß-trifluoromethylation and perfluoroalkylation of enamides with Togni reagent or perfluoroalkyl iodides is presented under transition-metal-free, photocatalyst-free and mild reaction conditions. Notably, using this photocatalyst-free strategy, direct trifluoromethylation and perfluoroalkylation of quinoxalin-2(1H)-one derivatives was also achieved via a photoactive electron donor-acceptor complex.

9.
Ying Yong Sheng Tai Xue Bao ; 35(6): 1716-1724, 2024 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-39235031

RESUMO

To investigate the differences on morphological growth patterns of statolith of Todarodes pacificus in the East China Sea during La Niña and normal years, we analyzed the samples of T. pacificus collected in the East China Sea by Chinese light purse seine fishery fleets from February to April in 2020 (a normal year) and 2021 (a La Niña year). The results showed that total statolith length (TSL), lateral dome length (LDL), wing length (WL), and maximum width (MW) could be used as characterization parameters to representing the morphological growth of statolith. The characterization parameters of statolith in T. pacificus differed significantly between different climate years and between different genders. The values of those characterization parameters of statolith were greater in normal year than those in La Niña year, which in both years were larger in females, except for TSL in males in La Niña year. The statolith growth of males were faster than that of females in different climate years. TSL, LDL, and WL increased faster in normal year, while MW increased faster in La Niña year. The relative size of statolith gradually slowed down with the growth of individuals.


Assuntos
Oceanos e Mares , China , Animais , Masculino , Feminino , Clima
10.
Adv Sci (Weinh) ; : e2406305, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39319609

RESUMO

Antimicrobial peptides (AMPs) are a promising solution for treating antibiotic-resistant pathogens. However, efficient generation of diverse AMPs without prior knowledge of peptide structures or sequence alignments remains a challenge. Here, ProT-Diff is introduced, a modularized deep generative approach that combines a pretrained protein language model with a diffusion model for the de novo generation of AMPs sequences. ProT-Diff generates thousands of AMPs with diverse lengths and structures within a few hours. After silico physicochemical screening, 45 peptides are selected for experimental validation. Forty-four peptides showed antimicrobial activity against both gram-positive or gram-negative bacteria. Among broad-spectrum peptides, AMP_2 exhibited potent antimicrobial activity, low hemolysis, and minimal cytotoxicity. An in vivo assessment demonstrated its effectiveness against a drug-resistant E. coli strain in acute peritonitis. This study not only introduces a viable and user-friendly strategy for de novo generation of antimicrobial peptides, but also provides potential antimicrobial drug candidates with excellent activity. It is believed that this study will facilitate the development of other peptide-based drug candidates in the future, as well as proteins with tailored characteristics.

11.
Huan Jing Ke Xue ; 45(8): 4600-4609, 2024 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-39168679

RESUMO

Microplastics pose a serious ecological threat to rivers in China, and the construction of a large number of dams has complicated this problem. Ten dams of the Shaying River were chosen to investigate the abundance and composition of microplastics in surface water and sediments of the reservoir and upstream river. Ecological risk was evaluated using species sensitive distribution (SSD) and pollution load index (PLI). The results showed that the Shaying River was exposed to a severe risk of microplastics from upstream to downstream. The construction of dams did not significantly affect the distribution of microplastics in the river. River sediments became a sink for microplastics in the surface water; however, the ecological risk posed by microplastics in the surface water was greater, and the comparison of the two assessment methods showed that the species sensitivity distribution assessment better reflected the accumulation and feeding behavior of organisms to pollutants compared to the pollution load index.


Assuntos
Monitoramento Ambiental , Microplásticos , Rios , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , China , Medição de Risco , Microplásticos/análise , Sedimentos Geológicos/química
12.
Orthop Surg ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39077885

RESUMO

OBJECTIVE: As the population ages and technology advances, lateral lumbar intervertebral fusion (LLIF) is gaining popularity for the treatment of degenerative lumbar scoliosis (DLS). This study investigated the feasibility, minimally invasive concept, and benefits of LLIF for the treatment of DLS by observing and assessing the clinical efficacy, imaging changes, and complications following the procedure. METHODS: A retrospective analysis was performed for 52 DLS patients (12 men and 40 women, aged 65.84 ± 9.873 years) who underwent LLIF from January 2019 to January 2023. The operation time, blood loss, complications, clinical efficacy indicators (visual analogue scale [VAS], Oswestry disability index [ODI], and 36-Item Short Form Survey), and imaging indicators (coronal position: Cobb angle and center sacral vertical line-C7 plumbline [CSVL-C7PL]; and sagittal position: sagittal vertical axis [SVA], lumbar lordosis [LL], pelvic incidence angle [PI], and thoracic kyphosis angle [TK] were measured). All patients were followed up. The above clinical evaluation indexes and imaging outcomes of patients postoperatively and at last follow-up were compared to their preoperative results. RESULTS: Compared to the preoperative values, the Cobb angle and LL angle were significantly improved after surgery (p < 0.001). Meanwhile, CSVL-C7PL, SVA, and TK did not change much after surgery (p > 0.05) but improved significantly at follow-up (p < 0.001). There was no significant change in PI at either the postoperative or follow-up timepoint. The operation took 283.90 ± 81.62 min and resulted in a total blood loss of 257.27 ± 213.44 mL. No significant complications occurred. Patients were followed up for to 21.7 ± 9.8 months. VAS, ODI, and SF-36 scores improved considerably at postoperative and final follow-up compared to preoperative levels (p < 0.001). After surgery, the Cobb angle and LL angle had improved significantly compared to preoperative values (p < 0.001). CSVL-C7PL, SVA, and TK were stable after surgery (p > 0.05) but considerably improved during follow-up (p < 0.001). PI showed no significant change at either the postoperative or follow-up timepoints. CONCLUSION: Lateral lumbar intervertebral fusion treatment of DLS significantly improved sagittal and coronal balance of the lumbar spine, as well as compensatory thoracic scoliosis, with good clinical and radiological findings. Furthermore, there was less blood, less trauma, and quicker recovery from surgery.

13.
J Agric Food Chem ; 72(32): 18201-18213, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39082219

RESUMO

The drive to enhance enzyme performance in industrial applications frequently clashes with the practical limitations of exhaustive experimental screening, underscoring the urgency for more refined and strategic methodologies in enzyme engineering. In this study, xylanase Xyl-1 was used as the model, coupling evolutionary insights with energy functions to obtain theoretical potential mutants, which were subsequently validated experimentally. We observed that mutations in the nonloop region primarily aimed at enhancing stability and also encountered selective pressure for activity. Notably, mutations in this region simultaneously boosted the Xyl-1 stability and activity, achieving a 65% success rate. Using a greedy strategy, mutant M4 was developed, achieving a 12 °C higher melting temperature and doubled activity. By integration of spectroscopy, crystallography, and quantum mechanics/molecular mechanics molecular dynamics, the mechanism behind the enhanced thermal stability of M4 was elucidated. It was determined that the activity differences between M4 and the wild type were primarily driven by dynamic factors influenced by distal mutations. In conclusion, the study emphasizes the pivotal role of evolution-based approaches in augmenting the stability and activity of the enzymes. It sheds light on the unique adaptive mechanisms employed by various structural regions of proteins and expands our understanding of the intricate relationship between distant mutations and enzyme dynamics.


Assuntos
Endo-1,4-beta-Xilanases , Estabilidade Enzimática , Mutação , Engenharia de Proteínas , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/metabolismo , Simulação de Dinâmica Molecular , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Cinética , Evolução Molecular Direcionada
14.
J Org Chem ; 89(16): 11173-11182, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39072554

RESUMO

Although the concerted [3 + 2] mechanism of osmium-catalyzed asymmetric dihydroxylation has been generally accepted, the unusual nonlinear Hammett relationship induced by amine-type ligands remains unexplained. To understand this, we carried out a density functional theory (DFT) study for the osmylation of substituted styrenes by the following: OsO4, OsO4-pyridine, OsO4-4-cyanopyridine, OsO4-4-pyrrolidinopyridine, and OsO4-quinuclidine. Calculations using the M06 functional successfully reproduce the experimentally observed nonlinear relationships. The transition states exhibit considerable singlet-diradical character, which causes the nonlinear Hammett relationship. Regardless of the presence or absence of an amine-type ligand, an electron donation from styrene to OsO4 is observed, indicating no mechanistic change. Calculations indicate that the electronic interaction between the amine-type ligand and styrene also influences the reaction rate.

15.
Cell Biol Int ; 48(9): 1240-1253, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38946126

RESUMO

Diabetic nephropathy (DN) is the predominant secondary nephropathy resulting in global end-stage renal disease. It is attracting significant attention in both domestic and international research due to its widespread occurrence, fast advancement, and limited choices for prevention and treatment. The pathophysiology of this condition is intricate and involves multiple molecular and cellular pathways at various levels. This article provides a concise overview of the molecular processes involved in the development of DN. It discusses various factors, such as signaling pathways, cytokines, inflammatory responses, oxidative stress, cellular damage, autophagy, and epigenetics. The aim is to offer clinicians a valuable reference for DN's diagnosis, treatment, and intervention.


Assuntos
Autofagia , Nefropatias Diabéticas , Estresse Oxidativo , Transdução de Sinais , Nefropatias Diabéticas/metabolismo , Humanos , Epigênese Genética , Citocinas/metabolismo , Animais , Inflamação/metabolismo
16.
Chemosphere ; 361: 142493, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38823426

RESUMO

Lignin-based carbon material can be utilized as carbonaceous adsorbents for the removal of toxic gaseous organic pollutants, while the poor heat-resistance limited its widely application. Here in, B-N co-doped lignin carbon (BN-C) with high thermal stability was synthesized, and the optimized BN-C (1:2) exhibited notably improved heat resistance with the decomposition temperature up to 505 °C, and excellent adsorption capacity for o-dichlorobenzene (o-DCB) (1510.0 mg/g) and toluene (947.3 mg/g), together with good cyclic stability over 10 cycles for o-dichlorobenzene. The existence of abundant hexagonal boron nitride (h-BN) with good thermal conductivity contributed to the superior heat-resistance of BN-C (1:2), and the high specific surface area (1764.5 m2/g), enriched hydroxyl functional groups and improved graphitization degree contributed to its enhanced adsorption performance. More importantly, BN-C (1:2) supported Ru could effectively remove o-DCB and toluene at wide temperature range (50-300 °C). The present work guided the development of heat-resistant lignin-derived adsorbent-catalyst for gaseous aromatic pollutants removal, which benefits both environmental protection and resource utilization.


Assuntos
Poluentes Atmosféricos , Lignina , Nitrogênio , Adsorção , Lignina/química , Catálise , Nitrogênio/química , Poluentes Atmosféricos/química , Temperatura Alta , Boro/química , Tolueno/química , Compostos de Boro/química , Carbono/química
17.
Nature ; 632(8024): 313-319, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38885695

RESUMO

Oligosaccharides have myriad functions throughout biological processes1,2. Chemical synthesis of these structurally complex molecules facilitates investigation of their functions. With a dense concentration of stereocentres and hydroxyl groups, oligosaccharide assembly through O-glycosylation requires simultaneous control of site, stereo- and chemoselectivities3,4. Chemists have traditionally relied on protecting group manipulations for this purpose5-8, adding considerable synthetic work. Here we report a glycosylation platform that enables selective coupling between unprotected or minimally protected donor and acceptor sugars, producing 1,2-cis-O-glycosides in a catalyst-controlled, site-selective manner. Radical-based activation9 of allyl glycosyl sulfones forms glycosyl bromides. A designed aminoboronic acid catalyst brings this reactive intermediate close to an acceptor through a network of non-covalent hydrogen bonding and reversible covalent B-O bonding interactions, allowing precise glycosyl transfer. The site of glycosylation can be switched with different aminoboronic acid catalysts by affecting their interaction modes with substrates. The method accommodates a wide range of sugar types, amenable to the preparation of naturally occurring sugar chains and pentasaccharides containing 11 free hydroxyls. Experimental and computational studies provide insights into the origin of selectivity outcomes.


Assuntos
Glicosídeos , Oligossacarídeos , Ácidos Borônicos/química , Brometos/química , Catálise , Glicosídeos/química , Glicosídeos/síntese química , Glicosilação , Ligação de Hidrogênio , Oligossacarídeos/química , Oligossacarídeos/síntese química , Sulfonas/química
18.
Front Med (Lausanne) ; 11: 1399744, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38933104

RESUMO

Intestinal ischemia/reperfusion is a prevalent pathological process that can result in intestinal dysfunction, bacterial translocation, energy metabolism disturbances, and subsequent harm to distal tissues and organs via the circulatory system. Acute lung injury frequently arises as a complication of intestinal ischemia/reperfusion, exhibiting early onset and a grim prognosis. Without appropriate preventative measures and efficacious interventions, this condition may progress to acute respiratory distress syndrome and elevate mortality rates. Nonetheless, the precise mechanisms and efficacious treatments remain elusive. This paper synthesizes recent research models and pertinent injury evaluation criteria within the realm of acute lung injury induced by intestinal ischemia/reperfusion. The objective is to investigate the roles of pathophysiological mechanisms like oxidative stress, inflammatory response, apoptosis, ferroptosis, and pyroptosis; and to assess the strengths and limitations of current therapeutic approaches for acute lung injury stemming from intestinal ischemia/reperfusion. The goal is to elucidate potential targets for enhancing recovery rates, identify suitable treatment modalities, and offer insights for translating fundamental research into clinical applications.

19.
Angew Chem Int Ed Engl ; 63(38): e202409332, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-38887822

RESUMO

Described herein is a dirhodium(II)-catalyzed silylation of propargyl esters with hydrosilanes, using tertiary amines as axial ligands. By adopting this strategy, a range of versatile and useful allenylsilanes can be achieved with good yields. This reaction not only represents a SN2'-type silylation of the propargyl derivatives bearing a terminal alkyne moiety to synthesize allenylsilanes from simple hydrosilanes, but also represents a new application of dirhodium(II) complexes in catalytic transformation of carbon-carbon triple bond. The highly functionalized allenylsilanes that are produced can be transformed into a series of synthetically useful organic molecules. In this reaction, an intriguing ON-OFF effect of the amine ligand was observed. The reaction almost did not occur (OFF) without addition of Lewis base amine ligand. However, the reaction took place smoothly (ON) after addition of only catalytic amount of amine ligand. Detailed mechanistic studies and density functional theory (DFT) calculations indicate that the reactivity can be delicately improved by the use of tertiary amine. The fine-tuning effect of the tertiary amine is crucial in the formation of the Rh-Si species via a concerted metalation deprotonation (CMD) mechanism and facilitating ß-oxygen elimination.

20.
Zhongguo Zhong Yao Za Zhi ; 49(9): 2461-2467, 2024 May.
Artigo em Chinês | MEDLINE | ID: mdl-38812145

RESUMO

In this study, the chemical components of ethanol extract from the aromatic parts of Syringa oblata were systematically separated and purified by silica gel column chromatography, thin layer plate preparation and liquid phase preparation. Combined with ultraviolet analyzer(UV), infrared analyzer(IR), nuclear magnetic resonance analyzer(NMR), high resolution mass spectrometer(HR-ESI-MS), X-ray diffraction and other spectrum technology as well as literature physicochemical data comparison methods for structural identification, a total of 10 compounds were identified. They were identified as oblatanoid D(1),(-)-T-muurolol(2), oblatanoid E-G(3-5), 14-noreudesma-3-hydroxy-3-en-2,9-dione(6), 1-isopropyl-2,7-dimethylnaphthalene(7), isocoradiol(8), α-calacorene(9), cadin-4-en-1-ß-ol(10). Compound 1 is a new sesquiterpene compound that has not been reported, and the other 9 compounds are isolated from S. oblata for the first time. The compound 1 has a significant protective effect on the LPS-induced inflammatory injury model of RAW264.7 cells.


Assuntos
Sesquiterpenos , Syringa , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Animais , Camundongos , Syringa/química , Células RAW 264.7 , Estrutura Molecular , Medicamentos de Ervas Chinesas/química , Espectroscopia de Ressonância Magnética , Difração de Raios X
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