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1.
Phys Chem Chem Phys ; 26(24): 17359-17369, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38860664

RESUMO

Boron-doped graphdiyne (B-GDY) material exhibits an excellent performance in electrocatalysis, ion transport, and energy storage. However, accurately identifying the structures of B-GDY in experiments remains a challenge, hindering further selection of suitable structures with the most ideal performance for various practical applications. In the present work, we employed density functional theory (DFT) to simulate the X-ray photoelectron spectra (XPS) and near-edge X-ray absorption fine-structure (NEXAFS) spectra of pristine graphdiyne (GDY) and six representative single boron-doped graphdiynes at the B and C K-edges to establish the structure-spectroscopy relationship. A notable disparity in the C 1s ionization potentials (IPs) between substituted and adsorbed structures is observed upon doping with a boron atom. By analyzing the C and B 1s NEXAFS spectra on energy positions, spectral widths, spectral intensities, and different spectral profiles, we found that the six single boron-doped graphdiyne configurations can be sensitively identified. Moreover, this study provides a reliable theoretical reference for distinguishing different single boron-doped graphdiyne structures, enabling accurate selection of B-GDY structures for diverse practical applications.

2.
Inorg Chem ; 62(42): 17115-17125, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37828769

RESUMO

Cu-O2 structures play important roles in bioinorganic chemistry and enzyme catalysis, where the bonding between the Cu and O2 parts serves as a fundamental research concern. Here, we performed a multiconfigurational study on the copper L2,3-edge X-ray absorption spectra (XAS) of two copper enzyme model complexes to gain a better understanding of the antibonding nature from the clearly interpreted structure-spectroscopy relation. We obtained spectra in good agreement with the experiments by using the restricted active space second-order perturbation theory (RASPT2) method, which facilitated reliable chemical analysis. Spectral feature interpretations were supported by computing the spin-orbit natural transition orbitals. All major features were assigned to be mainly from Cu 2p to antibonding orbitals between Cu 3d and O2 π*, Cu 3d-πO-O* (type A), and a few also to mixed antibonding/bonding orbitals between Cu 3d and O2 π, Cu 3d ± πO-O (type M). Our calculations provided a clear illustration of the interactions between Cu 3d and O2 π*/π orbitals that are carried in the metal L-edge XAS.

3.
Phys Chem Chem Phys ; 25(47): 32421-32429, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37782052

RESUMO

The experimental C 1s near-edge X-ray absorption fine-structure (NEXAFS) spectra of graphdiyne (GDY) show an evident change at different exposure periods, which is explained by oxidation. Herein, to better understand the structure-spectra relationship and the influence of oxidization, we performed a first-principles simulation of the NEXAFS spectra and X-ray photoelectron spectra (XPS) of both pure GDY and its four typical graphdiyne oxides (GDO) at the carbon K-edge. Pure GDY contains one sp2-hybridized (C1) and two sp-hybridized (C2, C3) carbons, while oxidation introduces more nonequivalent carbons. The experimental NEXAFS spectrum exhibits the lowest peak at ca. 285.8 eV. It was found that the C 1s → π* excitation from the sp2-hybridized carbon atoms (C1) in pure GDY and the sp-hybridized atoms (C2, C3) in GDOs contributes to this peak. The two weak resonances at around 289.0 and 290.6 eV in the experiment are contributed by the carbon atoms bonded to the oxygen atoms. Meanwhile, we found that oxidization leads to an increase in the C 1s ionization potentials (IPs) by 0.3-2.7 eV, which is consistent with the XPS experiments. Our calculations provide a clear explanation of the structure-spectra relationships of GDY and GDOs, and the signatures are useful for estimating the degree of oxidation.

4.
BMC Gastroenterol ; 22(1): 304, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35733109

RESUMO

BACKGROUND: Distinguishing strangulated bowel obstruction (StBO) from simple bowel obstruction (SiBO) still poses a challenge for emergency surgeons. We aimed to construct a predictive model that could distinctly discriminate StBO from SiBO based on the degree of bowel ischemia. METHODS: The patients diagnosed with intestinal obstruction were enrolled and divided into SiBO group and StBO group. Binary logistic regression was applied to identify independent risk factors, and then predictive models based on radiological and multi-dimensional models were constructed. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were calculated to assess the accuracy of the predicted models. Via stratification analysis, we validated the multi-dimensional model in the prediction of transmural necrosis both in the training set and validation set. RESULTS: Of the 281 patients with SBO, 45 (16.0%) were found to have StBO, while 236(84.0%) with SiBO. The AUC of the radiological model was 0.706 (95%CI, 0.617-0.795). In the multivariate analysis, seven risk factors including pain duration ≤ 3 days (OR = 3.775), rebound tenderness (OR = 5.201), low-to-absent bowel sounds (OR = 5.006), low levels of potassium (OR = 3.696) and sodium (OR = 3.753), high levels of BUN (OR = 4.349), high radiological score (OR = 11.264) were identified. The AUC of the multi-dimensional model was 0.857(95%CI, 0.793-0.920). In the stratification analysis, the proportion of patients with transmural necrosis was significantly greater in the high-risk group (24%) than in the medium-risk group (3%). No transmural necrosis was found in the low-risk group. The AUC of the validation set was 0.910 (95%CI, 0.843-0.976). None of patients in the low-risk and medium-risk score group suffered with StBO. However, all patients with bowel ischemia (12%) and necrosis (24%) were resorted into high-risk score group. CONCLUSION: The novel multi-dimensional model offers a useful tool for predicting StBO. Clinical management could be performed according to the multivariate score.


Assuntos
Obstrução Intestinal , Isquemia Mesentérica , Humanos , Obstrução Intestinal/diagnóstico por imagem , Obstrução Intestinal/etiologia , Intestino Delgado/diagnóstico por imagem , Isquemia , Necrose , Estudos Retrospectivos
5.
BMC Gastroenterol ; 22(1): 332, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35799135

RESUMO

BACKGROUND: Nasointestinal tubes (NITs) have been increasingly used in patients with small bowel obstruction (SBO); However, severe adverse events (SAEs) of NITs might threaten the lives of patients. The indications of NITs need to be identified. This study was designed to explore the indications for the insertion of NITs in patients with SBO and to suggest the optimal strategies for individuals based on the outcomes of SAEs. METHODS: After propensity score matching, 68 pairs were included (Success group and failure group). The occurrence of SAEs and the clinical parameters were compared between the SAE group and the non-SAE group. Independent risk factors were evaluated among the subgroups. A novel scoring system was established to detect the subgroups that would benefit from NITs insertion. RESULTS: Successful implementation of NITs could avoid hypochloremia (p = 0.010), SAEs (p = 0.001), pneumonia (p = 0.006). SAEs occurred in 13 of 136 (9.6%) patients who accepted NITs insertion treatment. Risk factors for SAEs included tumors (p = 0.002), reduced BMI (p = 0.048), reduced hemoglobin (p = 0.001), abnormal activated partial thromboplastin time (p = 0.015) and elevated white blood cells (p = 0.002). A novel risk scoring system consists of hemoglobin before NITs insertion (95% CI 0.685, 0.893) and bowel obstruction symptoms relieved after NITs insertion (95% CI 0.575, 0.900) had the highest area under curve for predicting the occurrence of SAEs. We divided the risk score system into 3 grades, with the increasing grades, the rates of SAEs surged from 1.3% (1/74) to (6/11) 54.5%. CONCLUSION: NITs successfully insertion could avoid SAEs occurrence in SBO conservative treatment. SBO patients without anemia and could be relieved after NITs insertion could be the potential benefit group for this therapy.


Assuntos
Obstrução Intestinal , Estudos de Casos e Controles , Humanos , Obstrução Intestinal/etiologia , Obstrução Intestinal/terapia , Intestino Delgado , Fatores de Risco
6.
Phys Chem Chem Phys ; 24(14): 8196-8207, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35311874

RESUMO

Polynitrogen molecules and ions are important building blocks of high energy density compounds (HEDCs). High energy bonds formed at the N sites can be effectively probed by X-ray photoelectron spectroscopy (XPS) at the N K-edge. In this work, with the density functional theory and the ΔKohn-Sham scheme, we simulated the N1s ionic potentials (IPs) of 72 common polynitrogen molecules [tetrazoles, pentazole (N5H), diazines, triazines, tetrazines, furazans, oxazoles and oxadiazoles], ions [pentazolate anion (cyclo-N5-), pentazenium cation (N5+), etc.], and molecular (NH3⋯N5H, H2O⋯N5H) and ionic (NH4+⋯N5-, H3O+⋯N5-) pairs, as well as mononitrogen relatives. These constitute a small theoretical database for absolute N1s IPs with an average accuracy of ca. 0.3 eV. To understand the structure-IP relationship within this family, effects of side substituent and bridging groups, local bonding types (amine or imine N), charge and protonation states, and vibronic coupling were analyzed based on selected systems. This study in the gas phase collects inherent chemical shifts of nitrogen in high-energy NN and NC bonds, which provides an essential reference into XPS interpretations of more complex HEDCs in the solid state. We especially highlight the evident N1s chemical shifts induced by protonation for nitrogen in the five-membered ring (N5H versus cyclo-N5-, ca. 7 eV; NH3⋯N5H versus NH4+⋯N5-, ca. 3 eV; H2O⋯N5H versus H3O+⋯N5-, ca. 2 eV), and suggest XPS as a sensitive tool in determining the hydrogen positions in pentanitrogen-based HEDCs.

7.
J Chem Phys ; 157(9): 094704, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36075707

RESUMO

Truncated cluster models represent an effective way for simulating x-ray spectra of 2D materials. Here, we systematically assessed the influence of two key parameters, the cluster shape (honeycomb, rectangle, or parallelogram) and size, in x-ray photoelectron (XPS) and absorption (XAS) spectra simulations of three 2D materials at five K-edges (graphene, C 1s; C3N, C/N 1s; h-BN, B/N 1s) to pursue the accuracy limit of binding energy (BE) and spectral profile predictions. Several recent XPS experiments reported BEs with differences spanning 0.3, 1.5, 0.7, 0.3, and 0.3 eV, respectively. Our calculations favor the honeycomb model for stable accuracy and fast size convergence, and a honeycomb with ∼10 nm side length (120 atoms) is enough to predict accurate 1s BEs for all 2D sheets. Compared to all these experiments, predicted BEs show absolute deviations as follows: 0.4-0.7, 0.0-1.0, 0.4-1.1, 0.6-0.9, and 0.1-0.4 eV. A mean absolute deviation of 0.3 eV was achieved if we compare only to the closest experiment. We found that the sensitivity of computed BEs to different model shapes depends on systems: graphene, sensitive; C3N, weak; and h-BN, very weak. This can be attributed to their more or less delocalized π electrons in this series. For this reason, a larger cluster size is required for graphene than the other two to reproduce fine structures in XAS. The general profile of XAS shows weak dependence on model shape. Our calculations provide optimal parameters and accuracy estimations that are useful for x-ray spectral simulations of general graphene-like 2D materials.

8.
Org Biomol Chem ; 17(34): 7854-7857, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31408075

RESUMO

A copper-catalyzed DTBP oxidative dual C-H sulfurization has been developed for the direct thiocarbamation of imidazopyridines using a combination of elemental sulfur and formamides as carbamothioyl surrogates. NBS (bromo succinimide) was found to promote the thiocarbamation in good yields. This dual C-H sulfurization strategy enables access to a wide range of carbamothioyl imidazoheterocycles without the use of highly toxic phosgene.

9.
Phys Chem Chem Phys ; 21(41): 22819-22830, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31608353

RESUMO

We performed a density functional theory (DFT) study on X-ray photoelectron (XPS) and absorption (XAS) spectra of graphitic carbon nitride (g-C3N4) nanosheets at the N and C K-edges. A combined cluster-periodic approach was employed to calculate XPS spectra, in which the core ionic potential (IP) of the solid 2D material was computed by subtracting the work function (obtained with periodic conditions) from the gas phase IP (obtained with large cluster models). With amino-terminated supermolecules of different sizes, we obtained convergent spectra and provide new assignments for 5 nitrogen [1 sp2; 4 sp3 (bridging, tertiary, and primary/secondary amino nitrogens)] and 4 carbon (all bonded with three nitrogens) local structures. A good agreement with experiments was obtained, with the N1s (C1s) main peak position differing by 0.1-0.2 eV (0.5-0.8 eV). Our simulations show that N1s XPS of pure g-C3N4 contains only two major features at 398.6 and 401.2 eV, contributed from sp2-N and sp3-N, respectively. The chemical shifts of all sp3-N are so close (deviating by 0.3-0.6 eV) that terminal amino groups -NHx (x = 1, 2) will only be distinguished in high-resolution measurements. In C1s XPS, all carbons show similar (deviation < 0.2 eV) IPs, as determined by the same nearest neighbors. We further excluded the effect of shake-up satellites that may change our XPS interpretations by equivalent core hole time-dependent DFT (ECH-TDDFT) simulations. The effect of vibronic coupling is small (redistribution is only 0.1-0.3 eV to the higher-energy region) in the N1s edge as estimated from the asymmetric main peak shape, and negligible in the C1s edge. Quicker size convergence was found in XAS than XPS. In N1s XAS, we identified a weak π* spectral feature at 400-401 eV for both -NHx and tertiary nitrogens. Our study provides a clear theoretical reference for X-ray spectral fingerprints of different local structures, which is useful for analysis of g-C3N4 based materials with various designed or unavoidable structural modifications. We also highlight our combined cluster-periodic approach in calculating the K-edge XPS spectra of general 2D materials which predicts accurate absolute values.

10.
BMC Vet Res ; 15(1): 446, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31818287

RESUMO

BACKGROUND: Leishmaniosis, a disease caused by pathogenic Leishmania parasites, remains an unresolved health problem in the New World and the Old World. It is well known that lizards can be infected by a subgenus of Leishmania parasites, i.e. Sauroleishmania, which is non-pathogenic to humans. However, evidence suggests that lizards may also harbor pathogenic Leishmania species including the undetermined Leishmania sp., discovered in our previous work. Leishmania DNA in lizard blood can be detected by using molecular methods, such as the polymerase chain reaction (PCR). RESULTS: Three hundred and sixteen lizards, representing 13 species of four genera, were captured for blood samples collection in Northwest China. Two reliable molecular markers (cytochrome b and heat shock protein 70 genes) were used for detection in the lizard blood samples, to confirm a widespread presence of pathogenic Leishmania parasites and the distribution pattern of Leishmania spp. in lizards from Northwest China. The PCR data indicated positive detection rate for Leishmania in all the tested lizards with an overall prevalence of 57.91% (183/316). Apart from lizard parasites like Leishmania tarentolae and Leishmania sp., several pathogenic Leishmania including L. turanica, L. tropica and L. donovani complex were identified by using phylogenetic analysis. Co-existence of different haplotypes was observed in most Leishmania DNA-positive lizards with an overall rate of 77.6% (142/183). Even mixed infections with different Leishmania species appeared to occur in the lizards with an overall rate of 37.7% (69/183). CONCLUSIONS: Lizards can harbor pathogenic Leishmania spp. Co-existence of different haplotypes or even species of Leishmania indicates mixed infections in natural lizard host. Lizards may contribute to the spread of Leishmania parasites. The pathogenic Leishmania species detected in lizards from Northwest China may be of great eco-epidemiological importance.


Assuntos
Leishmania/classificação , Leishmaniose/epidemiologia , Lagartos/parasitologia , Animais , China/epidemiologia , DNA de Protozoário/sangue , Haplótipos , Leishmania/genética , Lagartos/sangue , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
11.
J Phys Chem A ; 122(20): 4750-4755, 2018 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-29733610

RESUMO

XPS and NEXAFS spectra of four stable C40 isomers [29( C2), 31( C s), 38( D2), and 39( D5 d)] have been investigated theoretically. We combined density functional theory and the full core hole potential method to simulate C 1s XPS and NEXAFS spectra for nonequivalent carbon atoms of four stable C40 fullerene isomers. The NEXAFS showed obvious dependence on the four C40 isomers, and XPS spectra are distinct for all four isomers, which can be employed to identify the four stable structures of C40. Furthermore, the individual components of the spectra according to different categories have been investigated, and the relationship between the spectra and the local structures of C atoms was also explored.

12.
J Chem Theory Comput ; 20(14): 6125-6133, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38994655

RESUMO

Introducing a core hole significantly alters the electronic structure of a molecule, and various X-ray spectroscopy techniques are available for probing the valence electronic structure in the presence of a core hole. In this study, we visually demonstrate the influence of a core hole on valence excitations by computing the ultraviolet absorption spectra and the shake-up satellites in X-ray photoelectron spectra for pyrrole, furan, and thiophene, as complemented by the natural transition orbital (NTO) analysis over transitions with and without a core hole. Employing equivalent core hole time-dependent density functional theory (ECH-TDDFT) and TDDFT methods, we achieved balanced accuracy in both spectra for reliable comparative analysis. We tracked the same involved valence transition in both spectra, offering a vivid illustration of the core hole effect via the change in corresponding particle NTOs introduced by a 1s core hole on a Cα, Cß, or O atom. Our analysis deepens the understanding of the core hole effect on valence transitions, a phenomenon ubiquitously observed in general X-ray spectroscopic analyses.

13.
J Phys Chem Lett ; 15(23): 6051-6061, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38819966

RESUMO

Understanding proton transfer (PT) dynamics in condensed phases is crucial in chemistry. We computed a 2D map of N 1s X-ray photoelectron/absorption spectroscopy (XPS/XAS) for an organic donor-acceptor salt crystal against two varying N-H distances to track proton motions. Our results provide a continuous spectroscopic mapping of O-H···N↔O-··· H+-N processes via hydrogen bonds at both nitrogens, demonstrating the sensitivity of N 1s transient XPS/XAS to hydrogen positions and PT. By reducing the O-H length at N1 by only 0.2 Å, we achieved excellent theory-experiment agreement in both XPS and XAS. Our study highlights the challenge in refining proton positions in experimental crystal structures by periodic geometry optimizations and proposes an alternative scaled snapshot protocol as a more effective approach. This work provides valuable insights into X-ray spectra for correlated PT dynamics in complex crystals, benefiting future experimental studies.

14.
J Agric Food Chem ; 72(28): 15541-15551, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38959381

RESUMO

Benzimidazoles, the representative pharmacophore of fungicides, have excellent antifungal potency, but their simple structure and single site of action have hindered their wider application in agriculture. In order to extend the structural diversity of tubulin-targeted benzimidazoles, novel benzimidazole derivatives were prepared by introducing the attractive pyrimidine pharmacophore. 2-((6-(4-(trifluoromethyl)phenoxy)pyrimidin-4-yl)thio)-1H-benzo[d]imidazole (A25) exhibited optimal antifungal activity against Sclerotinia sclerotiorum (S. s.), affording an excellent half-maximal effective concentration (EC50) of 0.158 µg/mL, which was higher than that of the reference agent carbendazim (EC50 = 0.594 µg/mL). Pot experiments revealed that compound A25 (200 µg/mL) had acceptable protective activity (84.7%) and curative activity (78.1%), which were comparable with that of carbendazim (protective activity: 90.8%; curative activity: 69.9%). Molecular docking displayed that multiple hydrogen bonds and π-π interactions could be formed between A25 and ß-tubulin, resulting in a stronger bonding effect than carbendazim. Fluorescence imaging revealed that the structure of intracellular microtubules can be changed significantly after A25 treatment. Overall, these remarkable antifungal profiles of constructed novel benzimidazole derivatives could facilitate the application of novel microtubule-targeting agents.


Assuntos
Ascomicetos , Benzimidazóis , Fungicidas Industriais , Simulação de Acoplamento Molecular , Tubulina (Proteína) , Benzimidazóis/química , Benzimidazóis/farmacologia , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Fungicidas Industriais/síntese química , Relação Estrutura-Atividade , Ascomicetos/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/química , Doenças das Plantas/microbiologia , Estrutura Molecular , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo
15.
Asian J Surg ; 47(5): 2168-2177, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38461140

RESUMO

Adhesive small bowel obstruction (ASBO) causes a major burden in emergency medicine. Owing to in situ decompression, nasointestinal tube (NIT) placement has been increasingly used in clinical practice compared with traditional conservation (TC); however, the indications remain controversial. This study was designed to explore the indications for each treatment in ASBOs and then suggest the optimal strategy. After propensity score matching, 128 pairs were included (the NIT and TC groups). The occurrence of severe adverse events (SAEs), peri-treatment clinical parameters, and radiological features were compared between the successful and failed treatment groups. According to different stages of the entire treatment, the independent risk factors for adverse effects for ASBO were analysed in phase I and phase II. In phase I, normal red blood cells (RBC) levels (p = 0.011) and a balanced sodium ion level (p = 0.016) positively affected the outcomes of TC treatment. In phase II, for the TC group, the successful treatment rate reached 79.5% for patients with ASBOs whose normal RBC levels (p = 0.006) or decreasing white blood cells (WBC) levels (p = 0.014) after treatment. For the NIT group, the treatment success rate was 68.1% for patients whose electrolyte imbalance could be reversed or whose neutrophil count/lymphocyte ratio (NLR) levels was lower than 4.3 (p = 0.018). TC treatment is highly recommended for patients with normal RBC counts and sodium levels pretreatment. After dynamic monitoring of the treatment process, for both the TC and NIT groups, once ASBOs had elevated inflammatory biomarkers or irreversible electrolyte disturbances, surgical interference was preferred.


Assuntos
Obstrução Intestinal , Intestino Delgado , Humanos , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Obstrução Intestinal/terapia , Feminino , Masculino , Pessoa de Meia-Idade , Estudos de Casos e Controles , Idoso , Resultado do Tratamento , Aderências Teciduais/etiologia , Intubação Gastrointestinal/métodos , Adulto , Pontuação de Propensão , Descompressão Cirúrgica/métodos , Fatores de Risco
16.
Pest Manag Sci ; 79(7): 2443-2455, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36810950

RESUMO

BACKGROUND: Controlling bacterial infections in plants is a major challenge owing to the appearance of resistant strains. As a physical barrier, the bacterial biofilm helps bacterial infections acquire drug resistance by enabling bacteria to accommodate complex and volatile environmental conditions and avoid bactericidal effects. Thus, developing new antibacterial agents with antibiofilm potency is imperative. RESULTS: A series of simple triclosan derivatives containing isopropanolamine moiety were elaborately designed and assessed for their antibacterial behavior. Bioassay results showed that some title compounds had excellent bioactivity against three destructive bacteria Xanthomonas oryzae pv. oryzae (Xoo), Xanthomonas axonopodis pv. citri (Xac) and Pseudomonas syringae pv. actinidiae (Psa). Notably, compound C8 displayed high bioactivities toward Xoo and Xac, with EC50 values were 0.34 and 2.11 µg mL-1 , respectively. In vivo trials revealed that compound C8 exhibited excellent protective activities against rice bacterial blight and citrus bacterial canker at 200 µg mL-1 , with control effectivenesses of 49.57% and 85.60%, respectively. Compound A4 had remarkably inhibitory activity toward Psa, with an EC50 value of 2.63 µg mL-1 , and demonstrated outstanding protective activity with a value of 77.23% against Psa in vivo. Antibacterial mechanisms indicated that compound C8 dose-dependently prevented biofilm formation and extracellular polysaccharide production. C8 also significantly weakened the motility and pathogenicity of Xoo. CONCLUSION: This study contributes to the development and excavation of novel bactericidal candidates with broad-spectrum antibacterial activity by targeting bacterial biofilm to control refractory plant bacterial diseases. © 2023 Society of Chemical Industry.


Assuntos
Infecções Bacterianas , Oryza , Triclosan , Xanthomonas , Triclosan/farmacologia , Testes de Sensibilidade Microbiana , Oxidiazóis/química , Antibacterianos/farmacologia , Antibacterianos/química , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
17.
J Agric Food Chem ; 71(29): 11035-11047, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37450840

RESUMO

Nowadays, reactive oxygen species (ROS) have been acknowledged as promising bactericidal targets against pesticide-resistant bacteria. Herein, to further excavate more excellent ROS inducers, simple 1,2,3,4-tetrahydro-ß-carboline derivatives containing a 3-aminopropanamide moiety were prepared and assessed for their antibacterial potency. Notably, three promising compounds displayed significant antibacterial potency. Compound I29 exhibits excellent in vitro bioactivity, with an EC50 value of 5.73 µg/mL, and admirable in vivo activities (protective activity of 55.74% and curative activity of 65.50%) toward Xanthomonas oryzae pv. oryzae. Compound I16 has good activity in vitro, with an EC50 of 3.43 µg/mL, and outstanding bioactivities in vivo (protective activity of 92.50% and curative activity of 59.68%) against Xanthomonas axonopodis pv. citri. Compound I6 shows excellent in vitro bioactivity (EC50 = 2.86 µg/mL) and significant protective activity (94.02%) for preventing Pseudomonas syringae pv. actinidiae. Antibacterial mechanism investigations indicate that these compounds disrupt the balance of the redox system to kill bacteria. These simple 1,2,3,4-tetrahydro-ß-carboline derivatives are promising leads to the discovery of bactericidal agents.


Assuntos
Infecções Bacterianas , Oryza , Xanthomonas , Espécies Reativas de Oxigênio , Testes de Sensibilidade Microbiana , Doenças das Plantas/microbiologia , Antibacterianos/farmacologia , Antibacterianos/química , Oryza/microbiologia , Oxidiazóis/química
18.
World J Gastroenterol ; 29(9): 1509-1522, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36998422

RESUMO

BACKGROUND: Small bowel obstruction (SBO) still imposes a substantial burden on the health care system. Traditional evaluation systems for SBO outcomes only focus on a single element. The comprehensive evaluation of outcomes for patients with SBO remains poorly studied. Early intensive clinical care would effectively improve the short-term outcomes for SBO, however, the full spectrum of the potential risk status regarding the high complication-cost burden is undetermined. AIM: We aim to construct a novel system for the evaluation of SBO outcomes and the identification of potential risk status. METHODS: Patients who were diagnosed with SBO were enrolled and stratified into the simple SBO (SiBO) group and the strangulated SBO (StBO) group. A principal component (PC) analysis was applied for data simplification and the extraction of patient characteristics, followed by separation of the high PC score group and the low PC score group. We identified independent risk status on admission via a binary logistic regression and then constructed predictive models for worsened management outcomes. Receiver operating characteristic curves were drawn, and the areas under the curve (AUCs) were calculated to assess the effectiveness of the predictive models. RESULTS: Of the 281 patients, 45 patients (16.0%) were found to have StBO, whereas 236 patients (84.0%) had SiBO. Regarding standardized length of stay (LOS), total hospital cost and the presence of severe adverse events (SAEs), a novel principal component was extracted (PC score = 0.429 × LOS + 0.444 × total hospital cost + 0.291 × SAE). In the multivariate analysis, risk statuses related to poor results for SiBO patients, including a low lymphocyte to monocyte ratio (OR = 0.656), radiological features of a lack of small bowel feces signs (OR = 0.316) and mural thickening (OR = 1.338), were identified as risk factors. For the StBO group, higher BUN levels (OR = 1.478) and lower lymphocytes levels (OR = 0.071) were observed. The AUCs of the predictive models for poor outcomes were 0.715 (95%CI: 0.635-0.795) and 0.874 (95%CI: 0.762-0.986) for SiBO and StBO stratification, respectively. CONCLUSION: The novel PC indicator provided a comprehensive scoring system for evaluating SBO outcomes on the foundation of complication-cost burden. According to the relative risk factors, early tailored intervention would improve the short-term outcomes.


Assuntos
Obstrução Intestinal , Humanos , Obstrução Intestinal/diagnóstico , Obstrução Intestinal/etiologia , Fatores de Risco , Intestino Delgado/diagnóstico por imagem , Tempo de Internação , Estudos Retrospectivos
19.
Hum Reprod ; 27(2): 340-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22131388

RESUMO

BACKGROUND: The present study was designed to investigate the possible association between infertility of male uremic patients and expression of the cystic fibrosis transmembrane conductance regulator (CFTR) protein in their sperm. METHODS: Semen was collected and analyzed. Serum levels of FSH, LH and testosterone were measured by radioimmunoassay. The sperm CFTR expressions of 21 uremic patients and 15 renal transplant patients were measured and compared with those of 32 healthy and 33 infertile men. RESULTS: Only 9 ± 5.9% of sperm from uremic patients expressed CFTR, significantly less than those of the renal transplant patients (29 ± 14.3%, P< 0.001), the infertile men (42 ± 20.7%, P< 0.001) and the healthy men (51 ± 20.5%, P< 0.001). Furthermore, significantly fewer sperm from renal transplant patients expressed CFTR than those of the infertile men (P< 0.05) and the healthy men (P< 0.01). LH levels in uremic patients were significantly higher than in all other groups, whereas FSH levels in uremic patients were only significantly higher than in infertile and healthy men. There was no significant difference in testosterone level among the four categories. CONCLUSIONS: Sperm CFTR expression is depressed in uremic patients but recovers to some degree after renal transplant along with some improvement in fertility, indicating a 'reversible' change. These results suggest that the CFTR expression rate in sperm is correlated with the decline of uremic patients' fertility, and may be considered as a potential marker to assess the fertility of male uremic patients.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Regulação para Baixo , Infertilidade Masculina/etiologia , Espermatozoides/metabolismo , Uremia/metabolismo , Uremia/fisiopatologia , Adulto , Biomarcadores/metabolismo , Hormônio Foliculoestimulante Humano/sangue , Glomerulonefrite/fisiopatologia , Humanos , Infertilidade Masculina/fisiopatologia , Infertilidade Masculina/prevenção & controle , Falência Renal Crônica/etiologia , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/terapia , Transplante de Rim , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Análise do Sêmen , Índice de Gravidade de Doença , Espermatozoides/patologia , Testosterona/sangue , Uremia/sangue , Uremia/etiologia , Adulto Jovem
20.
Pest Manag Sci ; 78(8): 3404-3415, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35527698

RESUMO

BACKGROUND: Gradually aggravated disease caused by phytopathogenic bacteria severely restricts food security and crop yield, and few pesticides can relieve this severe situation. Thus, development and excavation of new agrochemicals with high bioactivity and novel action mechanism may be a feasible strategy to control intractable bacterial diseases. As a privileged molecular framework, steroid molecules exhibit diversiform bioactivities. Herein, a series of novel androst-4-ene derivatives were designed, synthesised and investigated for their antibacterial behaviour to excavate novel agrochemicals on the base of steroid molecules. RESULTS: Bioassay results indicated that target compounds displayed high bioactivities toward three destructive phytopathogenic bacteria, including Xanthomonas oryzae pv. oryzae (Xoo), Xanthomonas axonopodis pv. citri (Xac) and Pseudomonas syringae pv. actinidiae (Psa). Compound III19 displayed excellent in vitro antibacterial profiling (EC50  = 2.37 mg L-1 towards Xoo, EC50  = 2.10 mg L-1 towards Xac, EC50  = 9.50 mg L-1 towards Psa). Furthermore, compound III19 showed outstanding in vivo protective activities, with values of 81.81% and 58.75% towards kiwifruit bacterial canker and rice bacterial leaf blight, respectively. Analysis of the antibacterial mechanism disclosed that compound III19 enhanced host defence enzyme activities superoxide dismutase (SOD), peroxidase (POD), phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), and catalase (CAT) and increased the salicylate synthase content to induce host resistance. In addition, compound III19 increased the membrane permeability, destroyed the cell membrane and killed the bacteria. CONCLUSION: Given these profiles of target compounds, we highlight a new strategy for controlling intractable plant bacterial diseases by inducing plant resistance and targeting the bacterial cell membrane. © 2022 Society of Chemical Industry.


Assuntos
Infecções Bacterianas , Oryza , Xanthomonas , Agroquímicos , Antibacterianos , Testes de Sensibilidade Microbiana , Oxidiazóis/química , Doenças das Plantas/prevenção & controle
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