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1.
Inorg Chem ; 63(12): 5709-5717, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38484381

RESUMO

The electron transport layer (ETL) plays an important role in determining the conversion efficiency and stability of perovskite solar cells (PSCs). Here, TiO2 thin film was prepared by irradiating diisopropoxy diacetylacetone titanium precursor thin film with 172 nm vacuum ultraviolet (VUV) at a low temperature. The prepared TiO2 thin film has higher electron mobility and conductivity. As it is used as an ETL for MAPbI3 PSCs, its band structure is better matched with the perovskite, and at the same time, due to the good interface contact, more uniform perovskite crystals are formed. Most importantly, a large number of hydroxyl radicals were formed during VUV irradiation of the precursor film, which made up for the oxygen defect present on the surface of the TiO2 thin film, and were adsorbed to the film surface. These hydroxyl groups form hydrogen bonds with methylammonium (MA) components on the MAPbI3 buried surface, thus promoting the transfer of photogenerated electrons at the MAPbI3/ETL interface. The power conversion efficiency of PSCs fabricated in air with the ETL prepared by VUV irradiation is 20.46%, which is higher than that of the contrast solar cell based on the sintered ETL (17.96%).

2.
BMC Pediatr ; 24(1): 348, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769486

RESUMO

BACKGROUND: Acute complete gastric volvulus is a rare and life-threatening disease, which is prone to gastric wall ischemia, perforation, and necrosis. If it is not treated by surgery in time, the mortality rate can range from 30 to 50%. Clinical presentations of acute gastric volvulus are atypical and often mimic other abdominal conditions such as gastritis, gastroesophageal reflux, gastric dilation, and pancreatitis. Imaging studies are crucial for diagnosis, with barium meal fluoroscopy being the primary modality for diagnosing gastric volvulus. Cases of acute gastric volvulus diagnosed by ultrasound are rarely reported. CASE PRESENTATION: We reported a rare case of acute gastric volvulus in a 4-year-old Chinese girl who presented with vomiting and abdominal pain. Ultrasound examination revealed the "whirlpool sign" in the cardia region, raising suspicion of gastric volvulus. Diagnosis was confirmed by X-ray barium meal fluoroscopy, which indicated left-sided diaphragmatic hernia and obstruction at the cardia region. Surgical intervention confirmed our suspicion of acute complete gastric volvulus combined with diaphragmatic hernia. CONCLUSION: In this case, we reported an instance of acute complete gastric volvulus. Ultrasound revealed a "whirlpool sign" in the cardia, which is likely to be a key sign for the diagnosis of complete gastric volvulus.


Assuntos
Hérnias Diafragmáticas Congênitas , Volvo Gástrico , Humanos , Volvo Gástrico/complicações , Volvo Gástrico/diagnóstico por imagem , Volvo Gástrico/cirurgia , Volvo Gástrico/diagnóstico , Feminino , Pré-Escolar , Doença Aguda , Hérnias Diafragmáticas Congênitas/complicações , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/cirurgia , Ultrassonografia , Fluoroscopia
3.
Hereditas ; 161(1): 9, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38374144

RESUMO

Congenital fibrinogen disorders are a group of coagulation deficiencies caused by fibrinogen defects and are divided into four types, including afibrinogenemia, hypofibrinogenemia, dysfibrinogenemia, and hypodysfibrinogenemia. In this study, we collected a family with hypofibrinogenemia, and genetics analysis identify a novel pathogenic variants (c.668G > C, p.Arg223Thr) in the FGG gene. And electron microscope observation revealed significant changes in the ultrastructure of fibrin of the proband. Our research expands the phenotypic and genetic spectrum associated with the FGG gene, which would facilitate in genetic counselling and prenatal genetic diagnosis.


Assuntos
Afibrinogenemia , Povo Asiático , Fibrinogênio , Humanos , Afibrinogenemia/genética , Afibrinogenemia/congênito , Afibrinogenemia/diagnóstico , Povo Asiático/genética , China , Fibrinogênio/genética , Fibrinogênio/química , Mutação
4.
Phys Chem Chem Phys ; 25(44): 30627-30635, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37933177

RESUMO

Functionalizing single-walled carbon nanotubes (SWNTs) with light-harvesting molecules is a facile way to construct donor-acceptor nanoarchitectures with intriguing optoelectronic properties. Magnesium-centered bacteriochlorin (MgBC), chlorin (MgC), and porphyrin (MgP) are a series of tetrapyrrole macrocycles comprising a central metal and four coordinated aromatic or antiaromatic five-membered rings linked by methine units, which show excellent visible light absorption. To delineate the effects of the aromaticity of coordinated rings on the optoelectronic properties of the nanocomposites, the photoinduced energy and charge transfer dynamics between Mg-centered tetrapyrroles and SWNTs are explored. The results show that excited energy transfer (EET) can occur within MgP@SWNT ascribed to the stabilization of the highest occupied molecular orbital (HOMO) in MgP with the increase of aromatic coordinated rings, while only electron transfer can take place in MgBC@SWNT and MgC@SWNT. Non-adiabatic dynamics simulations demonstrate that electron and hole transfer from MgP to SWNT is asynchronous. The electron transfer is ultrafast with a timescale of ca. 50 fs. By contrast, the hole transfer is significantly suppressed, although it can be accelerated to some extent when using a lower excitation energy of 2.2 eV as opposed to 3.1 eV. Further analysis reveals that the large energy gaps between charge-donor and charge-acceptor states play a crucial role in regulating photoexcited state relaxation dynamics. Our theoretical insights elucidate the structure-functionality interrelations between Mg-centered tetrapyrroles and SWNTs and provide a comprehensive understanding of the underlying charge transfer mechanism within MgP@SWNT nanocomposites, which paves the way for the forthcoming development of SWNT-based photo-related functional materials with targeted applications.

5.
BMC Womens Health ; 23(1): 271, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-37198658

RESUMO

BACKGROUND: We aimed to compare the clinical efficacy of three surgical methods in the treatment of various types of cesarean scar pregnancy (CSP). METHODS: Herein, 314 cases of CSP were treated in the department of Obstetrics and Gynecology of the First Affiliated Hospital of Gannan Medical University between June 2017 and June 2020. The patients were divided into three groups based on the treatment received: group A (n = 146; curettage by pituitrin combined with ultrasonic monitoring and hysteroscopy-guided surgery), group B [n = 90; curettage after methotrexate (MTX) injection into the local gestational sac], and group C (n = 78; laparoscopic, transvaginal, and transabdominal cesarean scar resection). These groups were divided into three subgroups (type I, type II, and type III) according to the CSP type of the patients. RESULTS: The intraoperative blood loss, length of hospital stay, hospitalization cost, menstrual recovery time, and serum ß-HCG normalization time were lower in groups A than in groups B or C with type I, II and III CSP (P < 0.05). Operative efficiency and Successful second pregnancy rate were higher in groups A than in groups B or C with type I and II CSP (P < 0.05). But in type III CSP, the complications were more serious in group A than group C. CONCLUSIONS: Curettage by pituitrin combined with ultrasonic monitoring and hysteroscopy-guided surgery is an effective and relatively safe treatment for patients with type I and II CSP. Laparoscopic surgery is more suitable for type III CSP.


Assuntos
Gravidez Ectópica , Embolização da Artéria Uterina , Gravidez , Feminino , Humanos , Cicatriz/etiologia , Cicatriz/cirurgia , Cesárea/efeitos adversos , Estudos Retrospectivos , Gravidez Ectópica/cirurgia , Gravidez Ectópica/etiologia , Metotrexato/uso terapêutico , Resultado do Tratamento
6.
Planta ; 256(3): 54, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927530

RESUMO

MAIN CONCLUSION: For the first time it is reported that members of the nsLTP protein family could promote viral infection by inhibiting virus-induced RNA silencing. Non-specific lipid transfer proteins (nsLTPs) are a class of soluble proteins with low relative molecular weight and widely present in higher plants. The role of nsLTPs in biotic and abiotic stresses has been studied, but no report has shown that nsLTPs play a role in the process of viral infection. We report the function and mechanism of the classical nsLTP protein StLTP6 in viral infection. We found that StLTP6 expression was remarkably upregulated in potato infected with potato virus Y and potato virus S. The infection efficiency and virus content of StLTP6-overexpressed potato and Nicotiana benthamiana were remarkable increased. Further study found that the overexpression of StLTP6 inhibited the expression of multiple genes in the RNA silencing pathway, thereby inhibiting virus-induced RNA silencing. This result indicated that StLTP6 expression was induced during viral infection to inhibit the resistance of virus-induced RNA silencing and promote viral infection. In summary, we reported the role of StLTP6 in viral infection, broadening the biological function range of the nsLTP family and providing valuable information for the study of viral infection mechanism.


Assuntos
Solanum tuberosum , Viroses , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Doenças das Plantas/genética , Interferência de RNA , Solanum tuberosum/metabolismo , Viroses/genética
7.
Phys Chem Chem Phys ; 24(24): 15015-15024, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35695162

RESUMO

The possibility that the intramolecular Tr⋯S triel bond is strengthened by resonance is examined by quantum chemical calculations within the planar five-membered ring of TrH2-CRCR-CRS (Tr = Al, Ga, In; R = NO2, CH3). This internal bond is found to be rather short (2.4-2.7 Å) with a large bond energy between 12 and 21 kcal mol-1. The pattern of bond length alternation and atomic charges within the ring is consistent with resonance involving the conjugated double bonds. This resonance enhances the triel bond strength by some 25%. The electron-withdrawing NO2 group weakens the bond, but it is strengthened by the electron-donating CH3 substituent. NICS analysis suggests the presence of a certain degree of aromaticity within the ring.

8.
Phys Chem Chem Phys ; 24(42): 25895-25903, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36259982

RESUMO

When attached to a tetrazole, a TtR3 group (Tt = C, Si; R = H, F) engages in a Tt⋯N tetrel bond (TtB) with the Lewis base NCM (M = Li, Na). MP2/aug-cc-pVTZ calculations find that the Si⋯N TtB is rather strong, more than 20 kcal mol-1 for SiH3, and between 46 and 53 kcal mol-1 for SiF3. The C⋯N TtBs are relatively weaker, less than 8 kcal mol-1. All of these bonds are intensified when a BH3 or BF3 molecule forms a triel bond to a N atom of the tetrazole ring, particularly for the C⋯N TtB, up to 11 kcal mol-1. In these triads, the SiR3 group displaces far enough along the line toward the base that it may be thought of as half transferred.

9.
Medicina (Kaunas) ; 58(10)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36295504

RESUMO

Background and Objectives: To assess the efficacy and safety of hepatic arterial infusion chemotherapy (HAIC) with oxaliplatin plus raltitrexed (HAICROX) as an alternative treatment option for advanced hepatocellular carcinoma (HCC) patients who are ineligible for, or failed, the transarterial chemoembolization (TACE) treatment. Materials and Methods: From July 2020 to November 2021, a total of 35 HCC patients were enrolled and received HAIC with oxaliplatin plus raltitrexed. The overall survival (OS) and time to progression (TTP) were primary and secondary endpoints, respectively. The tumor response was assessed by the modified response evaluation criteria in solid tumors (mRECIST), and the adverse events were investigated using the common terminology criteria for adverse events version 5.0 (CTCAE 5.0). Results: The median OS and TTP were 10 months (95% confidence interval (CI): 5.5-14.6) and 3.5 months (95% CI: 2.3-4.7), respectively. By means of multivariate analysis, anti-programmed cell death protein 1 (anti-PD-1) immunotherapy was found to be an independent prognostic factor for better survival. No patients experienced toxicity-related death. Thrombocytopenia, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) elevation were the most common toxicities. No grade 3 or higher adverse events related to HAICROX were observed. Conclusion: HAICROX showed valuable efficacy and tolerable toxicity in advanced HCC patients who progressed on TACE or were ineligible for TACE. HAICROX is a promising treatment for advanced-stage HCC patients with TACE failure or ineligibility.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Oxaliplatina/uso terapêutico , Quimioembolização Terapêutica/efeitos adversos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Alanina Transaminase , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aspartato Aminotransferases , Resultado do Tratamento
10.
Medicina (Kaunas) ; 58(8)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-36013483

RESUMO

Background and Objectives: The recurrence outcome in patients who underwent microwave ablation (MWA) with or without transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) within Milan criteria remains unclear. The aim of this retrospective study was to identify the predictive factors of recurrence in these patients. Materials and Methods: From May 2018 to April 2021, 66 patients with HCC within Milan criteria were enrolled. Local tumor progression (LTP) and recurrence-free survival (RFS) were evaluated. Univariate and multivariate analyses were used to evaluate the risk factors of recurrence. The propensity score analysis was conducted to reduce potential confounding bias. Results: During the median follow-up of 25.07 months (95% confidence interval [CI], 21.85, 28.28), the median time to LTP and RFS were 20.10 (95%CI, 14.67, 25.53) and 13.03 (95%CI, 6.36, 19.70) months. No group difference (MWA vs. MWA + TACE) was found in 1-year cumulative LTP (p = 0.575) and RFS (p = 0.515), but meaningful significant differences were found in two-year recurrence (LTP, p = 0.007 and RFS, p = 0.037). Univariate and multivariate analyses revealed that treatment received before ablation was an independent risk factor of LTP (hazard ratio [HR] 4.37, 95%CI, 1.44, 13.32) and RFS (HR 3.41, 95%CI, 1.49, 7.81). Conclusions: The LTP and RFS in the MWA group were similar to that in the MWA combined with TACE. For HCC within Milan criteria, both groups preferentially selected MWA. More endeavor and rigorous surveillance should be taken to relapse prevention, in patients who have received previous treatment.


Assuntos
Carcinoma Hepatocelular , Ablação por Cateter , Quimioembolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento
11.
Eur J Immunol ; 50(8): 1174-1186, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32250445

RESUMO

Staphylococcus aureus, a pathogen most frequently found in diabetic foot ulcer infection, was recently suggested as an intracellular pathogen. Autophagy in professional phagocytes like macrophages allows selective destruction of intracellular pathogens, and its dysfunction can increase the survival of internalized pathogens, causing infections to worsen and spread. Previous works have shown that S. aureus infections in diabetes appeared more severe and invasive, and coincided with the suppressed autophagy in dermal tissues of diabetic rat, but the exact mechanisms are unclear. Here, we demonstrated that accumulation of advanced glycation end products (AGEs) contributed to the diminished autophagy-mediated clearance of S. aureus in the macrophages differentiated from PMA-treated human monocytic cell line THP-1. Importantly, infected macrophages showed increased S. aureus containing autophagosome, but the subsequent fusion of S. aureus containing autophagosome and lysosome was suppressed in AGEs-pretreated cells, suggesting AGEs blocked the autophagic flux and enabled S. aureus survival and escape. At the molecular level, elevated lysosomal ARL8 expression in AGEs-treated macrophages was required for AGEs-mediated inhibition of autophagosome-lysosome fusion. Silencing ARL8 in AGEs-treated macrophages restored autophagic flux and increased S. aureus clearance. Our results therefore demonstrate a new mechanism, in which AGEs accelerate S. aureus immune evasion in macrophages by ARL8-dependent suppression of autophagosome-lysosome fusion and bactericidal capability.


Assuntos
Fatores de Ribosilação do ADP/fisiologia , Produtos Finais de Glicação Avançada/fisiologia , Lisossomos/fisiologia , Macrófagos/imunologia , Fagocitose , Staphylococcus aureus/imunologia , Autofagossomos/fisiologia , Humanos , Evasão da Resposta Imune , Células THP-1 , Regulação para Cima
12.
Chemphyschem ; 22(22): 2305-2312, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34436816

RESUMO

The T⋅⋅⋅N tetrel bond (TB) formed between TX3 OH (T=C, Si, Ge; X=H, F) and the Lewis base N≡CM (M=H, Li, Na) is studied by ab initio calculations at the MP2/aug-cc-pVTZ level. Complexes involving TH3 OH contain a conventional TB with interaction energy less than 10 kcal/mol. This bond is substantially strengthened, approaching 35 kcal/mol and covalent character, when fluorosubstituted TF3 OH is combined with NCLi or NCNa. Along with this enhanced binding comes a near equalization of the TB T⋅⋅⋅N and the internal T-O bond lengths, and the associated structure acquires a trigonal bipyramidal shape, despite a high internal deformation energy. This structural transformation becomes more complete, and the TB is further strengthened upon adding an electron acceptor BeCl2 to the Lewis acid and a base to the NCM unit. This same TB strengthening can be accomplished also by imposition of an external electric field.

13.
Phys Chem Chem Phys ; 23(24): 13503-13511, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34120157

RESUMO

Carbon nanomaterials play important roles in modern scientific research. Integrating different carbon-based building blocks into nano-hybrid architectures not only takes full advantage of each component, but also brings in novel interfacial properties. Herein, we have employed density functional theory (DFT) calculations to investigate the effects of polymerization degree of coronene molecules encapsulated in single-walled carbon nanotubes (SWNTs) (19,0) on their interfacial properties. The present results reveal that the interfacial properties of the formed heterojunctions are remarkably regulated by the polymerization degree. For example, monomer- and dimer-encapsulated SWNTs are type-I heterojunctions in which interfacial excitation energy transfer is preferred, whereas interfacial charge carrier transfer is favorable in trimer- and polymer-encapsulated SWNTs because they are type-II heterojunctions. On the other hand, we have employed the time-domain nonadiabatic dynamics simulation approach to explore the interfacial carrier dynamics in type-II polymer-encapsulated SWNT heterojunctions. It is found that the electron and hole transfer processes are asymmetric and occur in opposite directions and at different rates. The former takes place from polymers to SWNTs in an ultrafast way (ca. 370 fs), whereas the latter occurs slowly from SWNTs to polymers (ca. 24 ps). A closer analysis uncovers the fact that the different carrier transfer rates mainly originate from the different densities of the acceptor states, energy differences and inter-state couplings between the donor and acceptor states. Finally, the present work demonstrates that the polymerization degree could act as a new regulating strategy to tune the interfacial properties of molecule-encapsulated SWNT heterojunctions.

14.
Molecules ; 26(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34770852

RESUMO

Carbonate MCO3 (M = Zn, Cd) can act as both Lewis acid and base to engage in a spodium bond with nitrogen-containing bases (HCN, NHCH2, and NH3) and a chalcogen bond with SeHX (X = F, Cl, OH, OCH3, NH2, and NHCH3), respectively. There is also a weak hydrogen bond in the chalcogen-bonded dyads. Both chalcogen and hydrogen bonds become stronger in the order of F > Cl > OH > OCH3 > NH2 > NHCH3. The chalcogen-bonded dyads are stabilized by a combination of electrostatic and charge transfer interactions. The interaction energy of chalcogen-bonded dyad is less than -10 kcal/mol at most cases. Furthermore, the chalcogen bond can be strengthened through coexistence with a spodium bond in N-base-MCO3-SeHX. The enhancement of chalcogen bond is primarily attributed to the charge transfer interaction. Additionally, the spodium bond is also enhanced by the chalcogen bond although the corresponding enhancing effect is small.

15.
Angew Chem Int Ed Engl ; 60(46): 24612-24619, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34523207

RESUMO

NiFe-layered double hydroxides (NiFe-LDH) are among the most active catalysts developed to date for the oxygen evolution reaction (OER) in alkaline media, though their long-term OER stability remains unsatisfactory. Herein, we reveal that the stability degradation of NiFe-LDH catalysts during alkaline OER results from a decreased number of active sites and undesirable phase segregation to form NiOOH and FeOOH, with metal dissolution underpinning both of these deactivation mechanisms. Further, we demonstrate that the introduction of cation-vacancies in the basal plane of NiFe LDH is an effective approach for achieving both high catalyst activity and stability during OER. The strengthened binding energy between the metals and oxygen in the LDH sheets, together with reduced lattice distortions, both realized by the rational introduction of cation vacancies, drastically mitigate metal dissolution from NiFe-LDH under high oxidation potentials, resulting in the improved long-term OER stability. In addition, the cation vacancies (especially M3+ vacancies) accelerate the evolution of surface γ-(NiFe)OOH phases, thereby boosting the OER activity. The present study highlights that tailoring atomic cation-vacancies is an important strategy for the development of active and stable OER electrocatalysts.

16.
Cytokine ; 126: 154868, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31629110

RESUMO

Lung cancer is a common malignant disease, nearly 2.09 million new patients occurred last year. Approximately 85% of the patients are classified as non-small-cell lung cancer (NSCLC). It is therefore important to identify new diagnostic and prognostic biomarkers for the early detection of this disease. The presented study identifies biomarkers in the serum of NSCLC patients. The expression of 274 cytokines was measured by a novel antibody array methodology and ELISA was applied to validate the array results. The levels of MIP-1 α, IL-8, MIP-1 ß, Resistin, GDF-15, HGF, CA125, FLRG, VCAM-1, DKK-3, sTNF-R1, CTACK, Acrp30, CXCL-16 and LYVE-1 were significantly higher in serum from NSCLC patients, while the level of TIMP-2 and IGFBP-6 were lower. More importantly, the validation supported the result of the antibody array. The result of the antibody array indicates that these cytokines might be novel auxiliary biomarkers in the diagnosis and prognosis of NSCLC.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Citocinas/sangue , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico , Adulto , Anticorpos , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Quimiocina CCL3/sangue , Quimiocina CCL3/genética , Citocinas/genética , Regulação para Baixo , Feminino , Humanos , Imuno-Histoquímica , Proteína 6 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 6 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise Serial de Proteínas , Reação em Cadeia da Polimerase em Tempo Real , Inibidor Tecidual de Metaloproteinase-2/sangue , Inibidor Tecidual de Metaloproteinase-2/genética , Regulação para Cima
17.
J Asian Nat Prod Res ; 22(7): 647-654, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31120358

RESUMO

One new epoxydon ester (1) and a new benzolactone derivative (2), along with four known compounds (3-6), were isolated from the insect-associated fungus Phoma sp. Their structures were confirmed by extensive MS and NMR spectroscopic analysis and their absolute configurations were determined by a combination of modified Mosher method and Mo2(OCOCH3)4-induced electronic circular dichroism (ECD) experiments. Compounds 1 and 5 were revealed to have potent antioxidant activities, which were approximate to the potency of the positive control trolox. In addition, 1 also exhibited moderate cytotoxic effect against human MGC-803 tumor cell line.[Formula: see text].


Assuntos
Antioxidantes , Ascomicetos , Animais , Dicroísmo Circular , Compostos de Epóxi , Humanos , Insetos , Estrutura Molecular
18.
J Phys Chem A ; 123(36): 7693-7703, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31419385

RESUMO

Understanding of photoinduced interfacial carrier dynamics in organic-transition metal dichalcogenides heterostructures is very important for the enhancement of their potential photoelectronic conversion efficiencies. In this work we have used density functional theory (DFT) calculations and DFT-based fewest-switches surface-hopping dynamics simulations to explore the photoinduced hole transfer and subsequent nonadiabatic electron-hole recombination dynamics taking place at the interface of pentacene and MoS2 in pentacene@MoS2. Upon photoexcitation the electronic transition mainly occurs on the MoS2 monolayer, which corresponds to moving an electron to the MoS2 conduction band. As a result, a hole is left in the valence band. This hole state is energetically lower than certain occupied states of the pentacene molecule; thus, the interfacial hole transfer from MoS2 to pentacene is favorable in energy. In terms of nonadiabatic dynamics simulations, the hole transfer time to the HOMO-1 state of the pentacene is estimated to be about 600 fs; however, the following hole relaxation process from HOMO-1 to HOMO takes much longer time of ca. 15 ps due to the large energy gap between HOMO-1 and HOMO. Moreover, our results also show that the subsequent radiationless recombination process between the hole transferred to the pentacene molecule and the remaining electron on the MoS2 CBM needs about 10.2 ns. The computational results shed important mechanistic insights on the interfacial carrier dynamics of mixed-dimensional pentacene@MoS2. These insights could help to design excellent interfaces for organic-TMDs heterostructures.

19.
J Clin Lab Anal ; 33(5): e22872, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30843276

RESUMO

BACKGROUND: Both Indole-amine-2,3-dioxygenase (IDO) and neutrophils were proved to have pro-tumor effect in some kinds of solid tumors by immune suppression. However, little is known about their effect on hepatocellular carcinoma (HCC) and the relationship between these two immune-suppressive factors. The aim of this study was to evaluate the prognostic significance of IDO and intra-tumoral neutrophils and their correlations in HCC. METHODS: Specimens' tissue microarray (TMA) for 153 HCC patients was used in this study. We examined intra-tumoral expression of IDO and CD66b in TMA. The Kaplan-Meier method and Cox regression models were used to evaluate the prognostic value of IDO expression and CD66b. RESULTS: Multivariate analysis showed both IDO expression and intra-tumoral neutrophils infiltration were independent prognostic factors for overall survival (OS). In high IDO expression group, the percentage of intra-tumoral neutrophils infiltration was higher than that in low IDO expression group. CONCLUSION: Both IDO and intra-tumoral neutrophils were independent prognostic factors for overall survival for HCC.


Assuntos
Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neutrófilos/patologia , Adulto , Idoso , Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/cirurgia , Moléculas de Adesão Celular/metabolismo , Feminino , Proteínas Ligadas por GPI/metabolismo , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Taxa de Sobrevida
20.
BMC Infect Dis ; 18(1): 122, 2018 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-29529992

RESUMO

BACKGROUND: Medical laboratory staff are a high-risk population for colonization of Staphylococcus aureus (S. aureus) due to direct and dense contact with the pathogens; however, there is limited information about this colonization. This study sought to determine the prevalence and molecular characteristics of nasal colonization by S. aureus in medical laboratory staff in Guangzhou, southern China, and to compare the differences between microbiological laboratory (MLS) and non-microbiological laboratory (NMLS) staff. METHODS: S. aureus colonization was assessed by nasal swab cultures from 434 subjects, including 130 MLSs and 304 NMLSs from 33 hospitals in Guangzhou. All S. aureus isolates underwent the antimicrobial susceptibility test, virulence gene detection and molecular typing. RESULTS: The overall prevalence of S. aureus carriage was 20.1% (87/434), which was higher in MLSs than in NMLSs (26.2% vs. 17.4%, P < 0.05), while the prevalence of Methicillin-resistant S. aureus (MRSA) was similar. Living with hospital staff was associated with S. aureus carriage. The majority of the isolates harboured various virulence genes, and those in MLSs appeared less resistant to antibiotics and more virulent than their counterparts. A total of 37 different spa types were detected; among these, t338, t437, t189 and t701 were the most frequently encountered types. T338 was the main spa type contributing to nasal colonization Methicillin-sensitive S. aureus (MSSA) (13.0%), and t437-SCCmec IV was predominant in MRSA isolates (40%). CONCLUSIONS: These findings provide insight into the risk factors, molecular epidemiology and virulence gene profiles of S. aureus nasal carriage among the medical laboratory staff in Guangzhou.


Assuntos
Cavidade Nasal/microbiologia , Staphylococcus aureus/isolamento & purificação , Virulência/genética , Adulto , Antibacterianos/farmacologia , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , China/epidemiologia , Feminino , Genótipo , Pessoal de Saúde , Hospitais , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem Molecular , Prevalência , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Adulto Jovem
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