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1.
Sci Rep ; 14(1): 16194, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003320

RESUMO

In the area of "returning farmland to forest" on the Loess Plateau in China, it is difficult to cultivate artificially planted trees into forests. In the current study, abandoned cultivated land after 10 years of natural restoration served as controls (CK), while the treatments included afforestation periods of 2, 4, 6, 8, and 10 years. Soil samples were collected from various depths: 0-20, 20-40, 40-60, 60-80, to 80-100 cm. The findings revealed that with increasing years of artificial afforestation, soil pH gradually increased, and soil moisture content rose in the 0-20 cm layer while declining in deeper layers (20-100 cm) in the Maxian Mountain region of the Loess Plateau. Moreover, the total carbon, nitrogen, phosphorus, and potassium content initially increased and then decreased with the duration of artificial afforestation, reaching peak values after 8 years. Contents of organic matter, ammonium nitrogen, nitrate nitrogen, available phosphorus, and available potassium in the same soil layer increased with each year of afforestation. However, upon reaching 10 years of artificial afforestation, the effective nutrient content in the 60-80 and 80-100 cm soil layers exhibited a decrease. The values of Integrated Fertility Index (IFI) in different afforestation years were ranked as follows: 8 years > 6 years > 10 years > 4 years > 2 year, but all of them were significantly smaller than those of natural restoration plot CK (P < 0.05). Overall, soil fertility in the Maxian Mountain area of the Loess Plateau increases with each additional year of artificial afforestation. However, when the artificial afforestation period is 10 years, soil fertility decreases and marking a shift from enhancement to decline beyond this duration.

2.
J Ovarian Res ; 17(1): 126, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890751

RESUMO

Ovarian cancer is a common malignant tumor in women, with a high mortality rate ranking first among gynecological tumors. Currently, there is insufficient understanding of the causes, pathogenesis, recurrence and metastasis of ovarian cancer, and early diagnosis and treatment still face great challenges. The sensitivity and specificity of existing ovarian cancer screening methods are still unsatisfactory. Centromere protein O (CENP-O) is a recently discovered structural centromere protein that is involved in cell death and is essential for spindle assembly, chromosome separation, and checkpoint signaling during mitosis. The abnormal high expression of CENP-O was detected in various tumors such as bladder cancer and gastric cancer, and it participates in the regulation of tumor cell proliferation. In this study, we detect the expression abundance of CENP-O mRNA in different ovarian cancer cells ( ES-2, A2780, Caov-3, OVCAR-3 and SK-OV-3). The biological function changes of cell proliferation and apoptosis were detected and the role of CENP-O in ovarian cancer cell proliferation and apoptosis was explored by knocking down the expression of CENP-O gene. The results showed that CENP-O gene was significantly expressed in 5 types of ovarian cancer cell lines. After knocking down the CENP-O gene, the proliferation and cloning ability of ovarian cancer cells decreased, and the apoptosis increased. This study indicates that CENP-O has the potential to be a molecular therapeutic target, and downregulating the expression of CENP-O gene can break the unlimited proliferation ability of cancer cells and promote their apoptosis, providing a foundation and new ideas for subsequent molecular mechanism research and targeted therapy.


Assuntos
Apoptose , Proliferação de Células , Proteínas Cromossômicas não Histona , Neoplasias Ovarianas , Feminino , Humanos , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia
3.
Reprod Domest Anim ; 59(6): e14598, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38881434

RESUMO

Our previous research has shown that melatonin (MLT) can reduce cryopreserved ovarian damage in mice. Yet, the molecular mechanism of MLT protection is still unclear. Some studies have shown that melatonin receptor 1 (MT1) is very important for animal reproductive system. To evaluate whether MLT exerts its protective effect on cryopreserved mice ovarian tissue via MT1, we added antagonist of MT1/MT2 (Luzindor) or antagonist of MT2 (4P-PDOT) to the freezing solution, followed by cryopreservation and thawing of ovarian tissue. The levels of total superoxide dismutase (T-SOD), catalase (CAT), nitric oxide (NO) and malondialdehyde (MDA) were detected. Besides, by using RT-PCR and Western blotting, the expression of Bcl-2, Bax and Nrf2/HO-1 signalling pathway-related proteins was detected. These findings demonstrated that compared with the melatonin group, the addition of Luzindor increased apoptosis, NO and MDA activities, decreased CAT and T-SOD activities and inhibited Nrf2/HO-1 signalling pathway. In conclusion, melatonin can play a protective role in cryopreserved ovarian tissue of mice through MT1 receptor.


Assuntos
Criopreservação , Melatonina , Fator 2 Relacionado a NF-E2 , Ovário , Estresse Oxidativo , Receptor MT1 de Melatonina , Transdução de Sinais , Animais , Feminino , Melatonina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ovário/efeitos dos fármacos , Receptor MT1 de Melatonina/metabolismo , Receptor MT1 de Melatonina/genética , Transdução de Sinais/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Camundongos , Criopreservação/veterinária , Triptaminas/farmacologia , Apoptose/efeitos dos fármacos , Heme Oxigenase (Desciclizante)/metabolismo , Heme Oxigenase (Desciclizante)/genética , Óxido Nítrico/metabolismo , Malondialdeído/metabolismo , Proteínas de Membrana , Heme Oxigenase-1
4.
BMC Oral Health ; 24(1): 540, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720327

RESUMO

OBJECTIVE: To investigate the effect of concentrated growth factor (CGF) combined with sodium hyaluronate (SH) on temporomandibular joint osteoarthritis (TMJOA). METHODS: Sixty patients with TMJOA who were diagnosed by cone-beam computed tomography (CBCT) between March 2020 and March 2023 at the Stomatological Hospital of Xi'an Jiaotong University were randomly divided into a control group (n = 30) and an experimental group (n = 30). The patients in the experimental group were treated with CGF + SH, and those in the control group were treated with SH only. The visual analogue scale (VAS) score indicating pain in the temporomandibular joint (TMJ) area; the Helkimo Clinical Dysfunction Index (Di); and changes in condylar CBCT at the first visit and 2 weeks, 3 months and 6 months after treatment were recorded. The CBCT data of the patients in the experimental and control groups were collected, and the three-dimensional CBCT image sequences were imported into Mimics Medical 19.0 software in DICOM format for condylar reconstruction. RESULTS: The VAS scores at 2 weeks, 3 months and 6 months after treatment were significantly lower in the experimental group than in the control group (P < 0.05), and the pain in the experimental group was significantly relieved. The Di was significantly lower in the experimental group than in the control group (P < 0.05), and the clinical function of the TMJ improved. After treatment, the CBCT score was significantly lower in the experimental group than in the control group (P < 0.05), and the condylar bone cortex was obviously repaired. Observation of the condylar bone cortex by three-dimensional reconstruction showed the same results as those obtained by CBCT. CONCLUSION: CGF combined with SH is effective in the treatment of TMJOA and can improve muscle pain, TMJ pain, Impaired TMJ function, Impaired range of movement, Pain on movement of the mandible and promote bone repair. THE REGISTRATION NUMBER (TRN): ChiCTR2400082712. THE DATE OF REGISTRATION: April 5, 2024.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Ácido Hialurônico , Osteoartrite , Transtornos da Articulação Temporomandibular , Humanos , Ácido Hialurônico/uso terapêutico , Ácido Hialurônico/administração & dosagem , Feminino , Masculino , Osteoartrite/tratamento farmacológico , Osteoartrite/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/tratamento farmacológico , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Adulto , Pessoa de Meia-Idade , Medição da Dor , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Resultado do Tratamento
5.
Huan Jing Ke Xue ; 45(2): 854-861, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471924

RESUMO

The aggregation and sedimentation of micro/nano-plastics significantly affect their migration and distribution in the environment. This study investigated the effects of Na+ and natural organic matter (NOM) on the aggregation and sedimentation of polystyrene nano-plastics (PS-NPs) in the aqueous phase. Six types of water, such as seawater, lake water, and domestic sewage, were used to evaluate the above effects and other potential influencing factors. The results indicated that Na+ could facilitate the sedimentation of PS-NPs when it was less than 80 mmol·L-1, whereas it could promote the aggregation and suspension of PS-NPs when the concentration was greater than 80 mmol·L-1. NOM molecules affected the aggregation and sedimentation of PS-NPs by changing the ζ potential and relative density of particles via forming a multilayer adsorption structure with Na+ on the particle surface. It was observed that NOM greater than 10 mg·L-1 enhanced the dispersion and suspension of PS-NPs, which might have been attributed to the decrease in relative density of the particles as a large amount of NOM was absorbed onto the surface. Compared with synthetic waters, environmental waters enhanced the aggregation of PS-NPs, which may have been related to the amino acid, protein, and other organic macro-molecules in the water.

7.
ACS Appl Mater Interfaces ; 16(13): 16132-16144, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38511296

RESUMO

The main impediment to the development of zinc-air batteries is the sluggish kinetics of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). Transition metal N-doped carbon catalysts offer a promising alternative to noble metal catalysts, with metal-organic framework (MOF)-derived carbon material catalysts being particularly noteworthy. Here, we synthesized MxP-Z-C carbon catalysts by combining two-dimensional (2D) metal porphyrin-based MOFs (MxPMFs, x = Fe, Co, Ni, Mn) and three-dimensional zeolitic imidazole framework-8 (ZIF-8) through electrostatic interaction, followed by carbonization. ZIF-8 was inserted between the layers of MxPMFs to prevent its Π-Π stacking, allowing the active sites to become fully exposed. MxP-Z-C demonstrated an impressive catalytic activity for both the ORR and the OER reactions. Among them, FeP-Z-C showed the best catalytic activity. The half-wave potential for ORR was 0.92 V (vs the reversible hydrogen electrode (RHE)), while the overpotential for the OER was 290 mV. In addition, the zinc-air battery assembled by FeP-Z-C exhibited high power density (133.14 mW cm-2) and significant specific capacity (816 mAh gZn-1), indicating considerable potential as a bifunctional catalyst for electronic devices.

8.
J Pediatr Nurs ; 75: e81-e92, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38195374

RESUMO

OBJECTIVES: To examine the effectiveness of near-infrared light devices (NIR) on procedure time of successful cannulation, success rate at the first attempt, and pain scores among pediatric patients and explore potential covariates on the intervention effect. BACKGROUND: Pediatric patients have encountered a high failure rate as compared with adult patients using traditional cannulation. NIR devices might help to access veins with an optimum viewing area and eliminate the number of attempts. However, methodological limitations and inconsistent results from previous reviews were found. METHODS: A three-step comprehensive search was performed in nine databases. Meta-analysis, subgroup, and meta-regression analyses were conducted. Individual quality assessment and certainty of evidence were assessed using the Cochrane risk of bias tool and the Grading of Recommendations, Assessments, Development, and Evaluation criteria, respectively. RESULTS: We included 18 randomized controlled trials (RCTs) with 5298 children and adolescents across nine countries. NIR light devices significantly reduce -29.43 s of procedure time and -0.47 attempts of peripheral intravenous cannulation compared with traditional methods. Subgroup analysis observed a significantly large effect size on procedure time using AccuVein with pre-procedure training at the clinics. However, NIR light devices do not significantly decrease the procedure time, first attempt success rate, and pain scores. Meta-regression identified sample size as a significant covariate that had an impact on the success rate at the first attempt. CONCLUSIONS: The near-infrared light device can statistically significantly reduce the procedure time and the number of attempts. Given the low or very low certainty of the evidence, future well-designed RCTs are necessary.


Assuntos
Cateterismo Periférico , Adolescente , Criança , Humanos , Cateterismo Periférico/métodos , Dor/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Acta Pharmacol Sin ; 45(5): 914-925, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38253637

RESUMO

Metrnl is a secreted protein involved in neurite outgrowth, insulin sensitivity, immunoinflammatory responses, blood lipids and endothelial protection. In this study, we investigated the role of Metrnl in ischemic stroke. Fifty-eight ischemic stroke patients (28 inpatient patients within 2 weeks of onset and 30 emergency patients within 24 h of onset) and 20 healthy controls were enrolled. Serum Metrnl was measured by enzyme-linked immunosorbent assay. We showed that serum Metrnl levels were significantly reduced in both inpatient and emergency patient groups compared with the controls. Different pathological causes for ischemic stroke such as large artery atherosclerosis and small artery occlusion exhibited similar reduced serum Metrnl levels. Transient ischemic attack caused by large artery atherosclerosis without brain infarction also had lower serum Metrnl levels. Metrnl was correlated with some metabolic, inflammatory and clotting parameters. Reduced serum Metrnl was associated with the severity of intracranial arterial stenosis and the presence of ischemic stroke. In order to elucidate the mechanisms underlying the reduced serum Metrnl levels, we established animal models of ischemic stroke in normal mice, atherosclerotic apolipoprotein E-knockout mice and Metrnl-knockout mice by middle cerebral artery occlusion (MCAO) using intraluminal filament or electrocoagulation. We demonstrated that serum Metrnl levels were significantly lower in atherosclerosis mice than normal mice, whereas acute ischemic stroke injury in normal mice and atherosclerosis mice did not alter serum Metrnl levels. Metrnl knockout did not affect acute ischemic stroke injury and death. We conclude that reduced serum Metrnl levels are attributed to the chronic vascular pathogenesis before the onset of ischemic stroke. Metrnl is a potential target for prevention of ischemic stroke.


Assuntos
Adipocinas , AVC Isquêmico , Humanos , Animais , Masculino , AVC Isquêmico/sangue , AVC Isquêmico/genética , Feminino , Pessoa de Meia-Idade , Idoso , Camundongos Endogâmicos C57BL , Camundongos , Infarto da Artéria Cerebral Média/sangue , Camundongos Knockout para ApoE
10.
Stroke Vasc Neurol ; 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38286483

RESUMO

The use of biologics in various diseases has dramatically increased in recent years. Stroke, a cerebrovascular disease, is the second most common cause of death, and the leading cause of disability with high morbidity worldwide. For biologics applied in the treatment of acute ischaemic stroke, alteplase is the only thrombolytic agent. Meanwhile, current clinical trials show that two recombinant proteins, tenecteplase and non-immunogenic staphylokinase, are most promising as new thrombolytic agents for acute ischaemic stroke therapy. In addition, stem cell-based therapy, which uses stem cells or organoids for stroke treatment, has shown promising results in preclinical and early clinical studies. These strategies for acute ischaemic stroke mainly rely on the unique properties of undifferentiated cells to facilitate tissue repair and regeneration. However, there is a still considerable journey ahead before these approaches become routine clinical use. This includes optimising cell delivery methods, determining the ideal cell type and dosage, and addressing long-term safety concerns. This review introduces the current or promising recombinant proteins for thrombolysis therapy in ischaemic stroke and highlights the promise and challenges of stem cells and cerebral organoids in stroke therapy.

11.
Nat Chem ; 16(3): 408-416, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38062248

RESUMO

The umpolung functionalization of imines bears vast synthetic potential, but polarity inversion is less efficient compared with the carbonyl counterparts. Strong nucleophiles are often required to react with the N-electrophiles without catalytic and stereochemical control. Here we show an effective strategy to realize umpolung of imines promoted by organocatalytic aromatization. The attachment of strongly electron-withdrawing groups to imines could enhance the umpolung reactivity by both electronegativity and aromatic character, enabling the direct amination of (hetero)arenes with good efficiencies and stereoselectivities. Additionally, the application of chiral Brønsted acid catalyst furnishes (hetero)aryl C-N atropisomers or enantioenriched aliphatic amines via dearomative amination from N-electrophilic aromatic precursors. Control experiments and density functional theory calculations suggest an ionic mechanism for the umpolung reaction of imines. This disconnection expands the options to forge C-N bonds stereoselectively on (hetero)arenes, which represents an important synthetic pursuit, especially in medicinal chemistry.

12.
Work ; 77(4): 1153-1163, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38007633

RESUMO

BACKGROUND: Occupational therapists (OT) assess and prescribe assistive devices to older adults with limitations in performing daily living activities. Timely prescription of assistive devices to accommodate the rising demand has been affected by the COVID-19 pandemic. Tele-assessment allows for continuity of care, but its success depends on therapists' acceptance. OBJECTIVE: This study examined OTs' perceptions of the feasibility of conducting tele-assessment and developing a clinical practice guideline for remote prescription of assistive devices for older adults in Singapore. METHODS: Eligible OTs were recruited from purposive sampling. Semi-structured interviews were conducted via a virtual platform (Zoom). Audio recordings were transcribed verbatim. Inductive thematic analysis using a line-by-line coding method was used to identify common trends. RESULTS: Interviews with 10 participants revealed three main themes: (1) therapists' perceptions of the feasibility of tele-assessment, (2) criteria for safe and appropriate prescription of assistive devices via tele-assessment, and (3) practical considerations for the implementation of tele-assessment. Participants felt that tele-assessment increases efficiency with more older adults being more receptive towards technology. They also raised suggestions to address OTs' concerns regarding the safety and accuracy prescription of assistive devices following tele-assessment. This included establishing the client's suitability for assistive device prescription, characteristics of assistive devices, resources required, and considering the preferences of stakeholders involved. CONCLUSION: Tele-assessment for assistive device prescription by OTs appears feasible in Singapore. OTs should consider collaborating with other stakeholders to develop a tele-assessment clinical practice guideline for assistive device prescription. Further studies testing its clinical effectiveness during and/or post-pandemic are warranted.


Assuntos
Terapeutas Ocupacionais , Tecnologia Assistiva , Humanos , Idoso , Singapura , Estudos de Viabilidade , Pandemias
13.
Inflamm Res ; 73(5): 693-705, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38150024

RESUMO

BACKGROUND: The aim of this study was to investigate the impact of Porphyromonas gingivalis (P. gingivalis) on the progression of oral squamous cell carcinoma (OSCC) through neutrophil extracellular traps (NETs) in the tumor immune microenvironment. METHODS: The expression of NETs-related markers was identified through immunohistochemistry, immunofluorescence, and Western blotting in different clinical stages of OSCC samples. The relationship between NETs-related markers and clinicopathological characteristics in 180 samples was analyzed using immunohistochemistry data. Furthermore, the ability to predict the prognosis of OSCC patients was determined by ROC curve analysis and survival analysis. The effect of P. gingivalis on the release of NETs was identified through immunofluorescence and immunohistochemistry, both in vitro and in vivo. CAL27 and SCC25 cell lines were subjected to NETs stimulation to elucidate the influence of NETs on various cellular processes, including cell proliferation, migration, invasion, and metastasis in vitro. Furthermore, the impact of NETs on the growth and metastatic potential of OSCC was assessed using in vivo models involving tumor-bearing mice and tumor metastasis mouse models. RESULTS: Immunochemistry analysis revealed a significant correlation between the NETs-related markers and clinical stage, living status as well as TN stage. P. gingivalis has demonstrated its ability to effectively induce the release of NETs both in vivo and in vitro. NETs have the potential to facilitate cell migration, invasion, and colony formation. Moreover, in vivo experiments have demonstrated that NETs play a pivotal role in promoting tumor metastasis. CONCLUSION: High expression of NETs-related markers demonstrates a strong correlation with the progression of OSCC. Inhibition of the NETs release process stimulated by P. gingivalis and targeted NETs could potentially open up a novel avenue in the field of immunotherapy for patients afflicted with OSCC.


Assuntos
Carcinoma de Células Escamosas , Armadilhas Extracelulares , Neoplasias Bucais , Porphyromonas gingivalis , Microambiente Tumoral , Porphyromonas gingivalis/imunologia , Humanos , Armadilhas Extracelulares/imunologia , Armadilhas Extracelulares/metabolismo , Microambiente Tumoral/imunologia , Animais , Neoplasias Bucais/imunologia , Neoplasias Bucais/patologia , Neoplasias Bucais/microbiologia , Linhagem Celular Tumoral , Feminino , Masculino , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Pessoa de Meia-Idade , Camundongos , Progressão da Doença , Camundongos Endogâmicos BALB C , Proliferação de Células , Movimento Celular , Camundongos Nus , Infecções por Bacteroidaceae/imunologia , Infecções por Bacteroidaceae/microbiologia , Neutrófilos/imunologia , Idoso
14.
Zhongguo Zhong Yao Za Zhi ; 48(21): 5915-5931, 2023 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-38114188

RESUMO

This study used UPLC-TQ-MS technology to replicate a Henoch-Schonlein purpura(HSP) model in rats by administering warm drugs by gavage and injecting ovalbumin with Freund's complete adjuvant emulsion. The distribution differences and characteristics of eight major components(ferulic acid, caffeic acid, neochlorogenic acid, cryptochlorogenic acid, benzoyl oxypaeoniflorin, tracheloside, loganin, and paeoniflorin) in rat liver, lung, heart, spleen, and kidney tissues were determined after oral administration of the Liangxue Tuizi Mixture at a dose of 42 g·kg~(-1) in both normal physiological and HSP states at 0.5, 1, 2, 6, and 12 hours. The results showed that the distribution patterns of the eight components of Liangxue Tuizi Mixture in the tissues of normal and HSP model rats were different. The main component, paeoniflorin, in Moutan Cortex and Paeoniae Radix Alba had higher content in all tissues. The eight components were predominantly distributed in the liver, lung, and kidney tissues, followed by spleen and heart tissues.


Assuntos
Vasculite por IgA , Ratos , Animais , Vasculite por IgA/tratamento farmacológico , Monoterpenos , Administração Oral , Espectrometria de Massa com Cromatografia Líquida
15.
Phys Chem Chem Phys ; 25(40): 27756-27765, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37814579

RESUMO

The substitution of oxygen with chalcogen in carbonyl group(s) of canonical nucleobases gives an impressive triplet generation, enabling their promising applications in medicine and other emerging techniques. The excited-state relaxation S2(ππ*) → S1(nπ*) → T1(ππ*) has been considered the preferred path for triplet generation in these nucleobase derivatives. Here, we demonstrate enhanced quantum efficiency of direct intersystem crossing from S2 to triplet manifold upon substitution with heavier chalcogen elements. The excited-state relaxation dynamics of sulfur/selenium substituted guanines in a vacuum is investigated using a combination of static quantum chemical calculations and on-the-fly excited-state molecular dynamics simulations. We find that in sulfur-substitution the S2 state predominantly decays to the S1 state, while upon selenium-substitution the S2 state deactivation leads to simultaneous population of the S1 and T2,3 states in the same time scale and multi-state quasi-degeneracy region S2/S1/T2,3. Interestingly, the ultrafast deactivation of the spectroscopic S3 state of both studied molecules to the S1 state occurs through a successive S3 → S2 → S1 path involving a multi-state quasi-degeneracy S3/S2/S1. The populated S1 and T2 states will cross the lowest triplet state, and the S1 → T intersystem crossing happens in a multi-state quasi-degeneracy region S1/T2,3/T1 and is accelerated by selenium-substitution. The present study reveals the influence of both the chalcogen substitution element and initial spectroscopic state on the excited-state relaxation mechanism of nucleobase photosensitizers and also highlights the important role of multi-state quasi-degeneracy in mediating the complex relaxation process. These theoretical results provide additional insights into the intrinsic photophysics of nucleobase-based photosensitizers and are helpful for designing novel photo-sensitizers for real applications.

16.
Nanotechnology ; 34(49)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37673043

RESUMO

Exploring highly active oxygen reduction electrocatalysts with low precious metals content is imperative but remains a considerable challenge. Herein, a series of heterobimetallic multi-walled carbon nanotubes (MWCNTs) electrocatalysts based on metal complexes are presented. These electrocatalysts feature diverse transition metals (M=Mn, Fe, Co, Ni) 5,15-bromophenyl-10, 20-methoxyphenyl porphyrin (MBMP) and tetrakis(triphenylphosphine)palladium (0) (Pd[P(Ph3)4]) anchored non-covalently on its surface. The resulting NiBMP-based MWCNTs with Pd[P(Ph3)4] (PdNiN4/MWCNTs) display outstanding electrocatalytic oxygen reduction activity (onset potential, 0.941 V; half wave potential, 0.830 V) and robust long-term durability in alkaline electrolyte. While in neutral condition, the MnBMP-based MWCNTs with Pd[P(Ph3)4] (PdMnN4/MWCNTs) are the most active heterobimetallic ORR catalyst and produce ultra-low concentration hydrogen peroxide (H2O2yield, 1.2%-1.3%). Synergistically tuning the ORR electrocatalytic activity and electron transfer pathway is achieved by the formation of NiBMP/MnBMP-Pd[P(Ph3)4] active sites. This work indicates such metalloporphyrin-Pd[P(Ph3)4] active sites on MWCNTs have significantly positive influence on electrocatalytic ORR systems and provides facile and mild strategy for designing highly efficient ORR electrocatalysts with ultra-low loading precious metal.

17.
Curr Probl Cancer ; 47(6): 101014, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37718231

RESUMO

Advanced-stage ovarian cancer is usually associated with peritoneal carcinomatosis. This study evaluates the prognostic role of the Peritoneal Cancer Index (PCI) in predicting the survival of patients with ovarian cancer. A literature search was conducted in electronic databases (Google Scholar, PubMed, Ovid, and Science Direct) and study selection was based on precise eligibility criteria. Random-effects meta-analyses were performed to estimate survival with low and high PCI scores and to pool hazard ratios (HR) of survival between lower and higher PCI scores. A total of 20 studies (2588 patients) were included. Median follow-up was 39 months [95%CI: 25, 54]. Complete cytoreduction rate was 80% [95% CI: 73, 87]. The median PCI score was 11.3 [95% CI: 9.9, 12.7]. Median survival was 56.7 months [95% CI: 45.2, 68.2] with below and 28.8 months [95% CI: 23.0, 34.6] with above any PCI cutoff. Most studies used PCI cutoffs between 10 and 20. The median progression-free survival was 23.7 months [95% CI: 16.5, 30.8] with below and 11.9 months [95% CI: 5.9, 17.9] with above any PCI cutoff. 5-year survival rates were 61.3% [95% CI: 49.9, 72.8] with PCI<10 cutoffs, 21.7% [95% CI: 11.6, 31.8] with PCI>10 cutoffs, 50.1% [95% CI: 39.0, 61.2] with PCI<20 cutoffs, and 21.7% [95% CI: 16.2, 27.1] with PCI>20 cutoffs. Pooled analysis of HRs showed that a higher PCI score was associated with worse survival in both univariate (HR 2.14 [95%CI: 1.63, 2.66]) and multivariate (HR 1.10 [95% CI: 1.02, 1.18]) analyses. In a set of studies that used varying PCI cutoffs, the PCI has been found to have a significant inverse association with the survival of patients with advanced ovarian cancer who underwent cytoreductive surgery.


Assuntos
Procedimentos Cirúrgicos de Citorredução , Neoplasias Ovarianas , Humanos , Feminino , Prognóstico , Estudos Retrospectivos , Neoplasias Ovarianas/cirurgia , Carcinoma Epitelial do Ovário , Taxa de Sobrevida
18.
J Am Chem Soc ; 145(39): 21152-21158, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37732875

RESUMO

Chiral cyclobutene units are commonly found in natural products and biologically active molecules. Transition-metal-catalysis has been extensively used in asymmetric synthesis of such structures, while organocatalytic approaches remain elusive. In this study, bicyclo[1.1.0]butanes are involved in enantioselective transformation for the first time to offer a highly efficient route toward cyclobutenes with good regio- and enantiocontrol. The utilization of N-triflyl phosphoramide as a chiral Brønsted acid promoter enables this isomerization process to proceed under mild conditions with low catalyst loading as well as good functional group compatibility. The resulting chiral cyclobutenes could serve as platform molecules for downstream manipulations with excellent reservation of stereochemical integrity, demonstrating the synthetic practicality of the developed method. Control experiments have also been performed to verify the formation of a key carbocation intermediate at the benzylic position.

19.
Poult Sci ; 102(12): 103066, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37769490

RESUMO

As an important respiratory organ, the lung is susceptible to damage during heat stress due to the accelerated breathing frequency caused by an increase in environmental temperature. This can affect the growth performance of animals and endanger their health. This study aimed to explore the mechanism of lung tissue damage caused by heat stress. Broilers were randomly divided into a control group (Control) and a heat stress group (HS). The HS group was exposed to 35°C heat stress for 12 h per d from 21-days old, and samples were taken from selected broilers at 28, 35, and 42-days old. The results showed a significant increase in lactate dehydrogenase (LDH) activity in the serum and myeloperoxidase (MPO) activity in the lungs of broiler chickens across all 3 age groups after heat stress (P < 0.01), while the total antioxidant capacity (T-AOC) was significantly enhanced at 35-days old (P < 0.01). Heat stress also led to significant increases in various proinflammatory factors in serum and expression levels of HSP60 and HSP70 in lung tissue. Histopathological results showed congestion and bleeding in lung blood vessels, shedding of pulmonary epithelial cells, and a large amount of inflammatory infiltration in the lungs after heat stress. The mRNA expression of TLRs/NF-κB-related genes showed an upward trend (P < 0.05) after heat stress, while the mRNA expression of MLCK, a gene related to pulmonary blood-air barrier, significantly increased after heat stress, and the expression levels of MLC, ZO-1, and occludin decreased in contrast. This change was also confirmed by Western blotting, indicating that the pulmonary blood-air barrier is damaged after heat stress. Heat stress can cause damage to the lung tissue of broiler chickens by disrupting the integrity of the blood-air barrier and increasing permeability. This effect is further augmented by the activation of TLRs/NF-κB signaling pathways leading to an intensified inflammatory response. As heat stress duration progresses, broiler chickens develop thermotolerance, which gradually mitigates the damaging effects induced by heat stress.


Assuntos
Suplementos Nutricionais , Lesão Pulmonar , Animais , Suplementos Nutricionais/análise , NF-kappa B/genética , NF-kappa B/metabolismo , Galinhas/fisiologia , Lesão Pulmonar/veterinária , Barreira Alveolocapilar/metabolismo , Resposta ao Choque Térmico , Transdução de Sinais , RNA Mensageiro/metabolismo , Temperatura Alta
20.
J Cancer ; 14(9): 1660-1672, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37325056

RESUMO

Objectives: Head and neck squamous cell carcinoma (HNSCC) is the most common malignancy of the head and neck. However, the molecular mechanisms governing the development of HNSCC have not been fully elucidated. Materials and Methods: Differentially expressed genes (DEGs) were screened out from The Cancer Genome Atlas (TCGA) and GSE23036 datasets. Weighted gene coexpression network analysis (WGCNA) was used to reveal the correlations among genes and to search for significantly correlated gene modules. The expression levels of genes in HNSCC and normal samples according to antibody-based detected methods was assessed by utilizing the Human Protein Atlas (HPA). The impact of the selected hub genes on the prognosis of HNSCC patients was assessed by analysing immunohistochemistry (IHC) and immunofluorescence (IF) expression levels and clinical data. Results: Twenty-four genes positively correlated with tumour status and 15 genes negatively correlated with tumour status were screened out by WGCNA. PLAU and LAMC2 were associated with a poor prognosis in patients with HNSCC and were finally screened out and verified by GEPIA and HPA database analysis. Immunohistochemistry of samples collected from 175 patients with HNSCC and subsequent statistical analysis also showed that PLAU and LAMC2 were associated with a poor prognosis in patients with HNSCC, and the levels of these two factors were positively correlated. The expression and co-localization of PLAU and LAMC2 in HNSCC tissues were confirmed by double immunofluorescence labeling. Conclusions: There was a positive correlation between PLAU and LAMC2 expression in HNSCC samples, and PLAU and LAMC2 might be independent prognostic biomarkers for HNSCC.

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