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1.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1549-1557, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621938

RESUMO

The dichloromethane fraction of Kadsura heteroclita roots was separated and purified by chromatographic techniques(e.g., silica gel, Sephadex LH-20, ODS, MCI column chromatography) and semi-preparative HPLC. Twenty compounds were isolated from K. heteroclita, and their structures were identified by NMR, MS, UV, and X-ray single crystal diffraction techniques. Twenty compounds were isolated from K. heteroclita, which were identified as xuetongdilactone G(1), mallomacrostin C(2), 3,4-seco(24Z)-cychmrt-4(28),24-diene-3,26-dioic acid 3-methyl ester(3), nigranoic acid(4), methyl ester schizanlactone E(5), schisandronic acid(6), heteroclic acid(7), wogonin(8),(2R,3R)-4'-O-methyldihydroquercetin(9), 15,16-bisnor-13-oxo-8(17),11E-labdadien-19-oic acid(10), stigmast-4-ene-6ß-ol-3-one(11), psoralen(12),(1R,2R,4R)-trihydroxy-p-menthane(13), homovanillyl alcohol(14), 2-(4-hydroxyphenyl)-ethanol(15), coniferaldehyde(16),(E)-7-(4-hydroxy-3-methoxyphenyl)-7-methylbut-8-en-9-one(17), acetovanillone(18), vanillic acid(19) and vanillin(20). Compound 1 is a new compound named xuetongdilactone G. Compounds 2-3 and 8-20 are isolated from K. heteroclita for the first time.


Assuntos
Kadsura , Kadsura/química , Espectroscopia de Ressonância Magnética , Raízes de Plantas/química , Ésteres/análise
2.
Mol Biol Cell ; : mbcE23110439, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568782

RESUMO

Cilia generate three-dimensional waveforms required for cell motility and transport of fluid, mucus, and particles over the cell surface. This movement is driven by multiple dynein motors attached to nine outer doublet microtubules that form the axoneme. The outer and inner arm dyneins are organized into 96 nm repeats tandemly arrayed along the length of the doublets. Motility is regulated in part by projections from the two central pair microtubules that contact radial spokes located near the base of the inner dynein arms in each repeat. Although much is known about the structures and protein complexes within the axoneme, many questions remain about the regulatory mechanisms that allow the cilia to modify their waveforms in response to internal or external stimuli. Here we used Chlamydomonas mbo (move backwards only) mutants with altered waveforms to identify at least two conserved proteins, MBO2/CCDC146 and FAP58/CCDC147, that form part of a L-shaped structure that varies between doublet microtubules. Comparative proteomics identified additional missing proteins that are altered in other motility mutants, revealing overlapping protein defects. Cryo-electron tomography and epitope tagging revealed that the L-shaped, MBO2/FAP58 structure interconnects inner dynein arms with multiple regulatory complexes, consistent with its function in modifying the ciliary waveform. [Media: see text].

3.
Chem Sci ; 15(9): 3140-3147, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38425526

RESUMO

As an emerging class of metal-free catalysts, frustrated Lewis pairs (FLPs) catalysts have been greatly constructed and applied in many fields. Homogeneous FLPs have witnessed significant development, while limited heterogeneous FLPs catalysts are available. Herein, we report that heterogeneous FLPs on pentacoordinated Al3+-enriched Al2O3 readily promote the heterolytic activation of H2 and thus hydrogenation catalysis. The defect-rich Al2O3 was prepared by simple calcination of a carboxylate-containing Al precursor. Combinatorial studies confirmed the presence of rich FLPs on the surface of the defective Al2O3. In contrast to conventional alumina (γ-Al2O3), the FLP-containing Al2O3 can activate H2 in the absence of any transition metal species. More importantly, H2 was activated by surface FLPs in a heterolytic pathway, leading to the hydrogenation of styrene in a stepwise process. This work paves the way for the exploration of more underlying heterogeneous FLPs catalysts and further understanding of accurate active sites and catalytic mechanisms of heterogeneous FLPs at the molecular level.

4.
Int J Nanomedicine ; 19: 1923-1949, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38435755

RESUMO

Exosomes, small extracellular vesicles derived from cells, are known to carry important bioactive molecules such as proteins, nucleic acids, and lipids. These bioactive components play crucial roles in cell signaling, immune response, and tumor metastasis, making exosomes potential diagnostic biomarkers for various diseases. However, current methods for detecting tumor exosomes face scientific challenges including low sensitivity, poor specificity, complicated procedures, and high costs. It is essential to surmount these obstacles to enhance the precision and dependability of diagnostics that rely on exosomes. Merging DNA signal amplification techniques with the signal boosting capabilities of nanomaterials presents an encouraging strategy to overcome these constraints and improve exosome detection. This article highlights the use of DNA signal amplification technology and nanomaterials' signal enhancement effect to improve the detection of exosomes. This review seeks to offer valuable perspectives for the enhancement of amplification methods applied in practical cancer diagnosis and prognosis by providing an overview of how these novel technologies are utilized in exosome-based diagnostic procedures.


Assuntos
Exossomos , Vesículas Extracelulares , Neoplasias , Humanos , Neoplasias/diagnóstico , Biomarcadores , DNA
5.
Plant Dis ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549275

RESUMO

Cordyline fruticosa is a shrub plant, commonly used in landscape, and distributed in the tropical regions of southern China. In September 2022, anthracnose symptoms were found on this species in Nanning, Guangxi, China. The disease incidence was between 30% to 80% and disease severity was 10% to 30% in five surveyed planting areas. The symptoms initially appeared as small, round, brown spots on leaves. As the disease developed, the lesions turned gray-white with brown borders and yellow halos. Some spots coalesced into larger irregular shapes and even leading to leaf blight. Small segments of the diseased tissues (3×3 mm) were cut from the leaves, surface-sterilized by dipping in a 1% sodium hypochlorite solution for 1 min, rinsed three times with sterile distilled water, and plated on potato dextrose agar (PDA). These plates were incubated at 28°C in the dark for 5 days. Ten fungal isolates with similar morphology were consistently isolated from these diseased tissues. The colonies on PDA were initially white with sparse aerial mycelia and turned pale orange with abundant orange conidial masses on the center after 8 days of culture. The reverse color was pale orange. No sclerotia or setae were found in culture. Conidia were single-celled, hyaline, straight, cylindrical with round ends, and 12.2 to 17.8 µm long (mean 14.9 µm) and 3.9 to 7.3 µm wide (mean 4.8 µm, n=50). The morphological characteristics of these isolates were similar to the Colletotrichum cordylinicola (Sharma et al., 2014). Genomic DNA of two isolates Z3 and Z4 generated from monospore culture was extracted using a fungal DNA extraction kit (Solarbio, Beijing, China). Partial sequences of internal transcribed spacer (ITS), partial actin (ACT), chitin synthase (CHS-1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and beta-tubulin (TUB2) were amplified using the primer pairs ITS1/ITS4, ACT-512F/ACT-783R, CHS-79F/CHS-345R, GDF1/GDR1, and BT2A/BT2B (Lin et al., 2022), respectively. All the sequences (GenBank accession nos. OQ509909, OQ509910, OQ658690, OQ658691, and OK649310 to OK649314) showed 99% to 100% identity with those of C. cordylinicola in GenBank database. A phylogenetic tree based on concatenated sequences of ITS, ACT, CHS-1, TUB, and GAPDH using maximum likelihood analysis by MEGA X software revealed that Z3 and Z4 clade with reference strains of C. cordylinicola (OJX010226 and MK935473). Based on morphological observation and multi-gene sequence analysis, the isolates were identified as C. cordylinicola (Phoulivong et al., 2010). To assess their pathogenicity, conidial suspensions (106 conidia/ml) of C. cordylinicola were inoculated onto 10 healthy living leaves wounded by slight puncturing (10 µl/wounded spot). Control leaves were treated with sterile water. All inoculated and control plants were maintained under high relative humidity (~90%) and 28℃ in a climate chamber. After 8 days, all the inoculated leaves showed brown lesions resembling natural symptoms, whereas the control group remained symptom-free. The same fungus was re-isolated from the symptomatic leaves, thus completing Koch's postulates. C. cordylinicola is a species of the C. gloeosporioides complex (Weir et al., 2012). It has been reported to cause anthracnose on C. fruticosa in USA and Thailand (Phoulivong et al., 2010; Sharma et al., 2014). To our knowledge, this is the first report of C. cordylinicola causing anthracnose on C. fruticosa in China. Knowing the causal agent is essential to control the serious disease effectively.

6.
Int J Oral Maxillofac Implants ; 0(0): 1-30, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394443

RESUMO

PURPOSE: To evaluate bone preservation and aesthetic recovery between the socketshield technique (SST) with different labial bone plate thicknesses and the conventional immediate implant technique (CIIT). MATERIALS AND METHODS: Patients who underwent immediate implant placement in the anterior region were divided into three groups: the SST with a thick-wall phenotype (> 1 mm) (SSTA group), the SST with a thin-wall phenotype (< 1 mm) (SSTB group) and the CIIT with a thick-wall phenotype (> 1 mm) (CIIT group). Radiological images and clinical photos were collected before surgery and immediately and six months postoperatively. The labial bone width and labial bone width change (BWC), labial bone volume change (BVC), pink aesthetic score (PES) and complication rate were evaluated among the three groups. Statistical analysis was performed using SPSS software. RESULTS: Twenty people in each group (60 people total) were enrolled in this six-month retrospective study. The BWC in the SSTA group (0.22-0.30 mm) and the SSTB group (0.18-0.33 mm) was less than that in the CIIT group (0.61-0.80 mm, p<0.004). The SSTA group and the SSTB group had a lower BVC (24.08 vs. 21.14 vs. 54.81, p=0.004) and greater PES (11.75 vs. 11.65 vs. 10.65, p=0.009) than the CIIT group. No complications occurred among these patients. CONCLUSIONS: With the limitations of this study, we can conclude that the SST is a reliable method for preserving bone and achieving satisfactory aesthetic outcomes. The labial bone plate phenotype associated with the SST has minimal impact on both clinical and radiological outcomes.

7.
Plant Dis ; 2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38311794

RESUMO

Banana (Musa spp.) is an economically important fruit and food crop globally as well as in China. In March 2023, a bulb rot disease was observed on more than 20% of cultivated dwarf bananas in a plantation in Wuming County of Guangxi Province, a major hub of banana production in China. Infected plants showed crackles at the basal part of stem and were relatively dwarf, while yellowing of the leaves was not observed. When the rhizomes were cut open, water-soaked lesions with a yellow or black margin can be seen in the bulb. In severe infections, the internal tissue became dry or wet rot, and there was typical dark-brown cavity formation in the bulb. The rot was limited to the bulb. To isolate the causal agent, dissected diseased tissues (5×5 mm) were surface sterilized with 75% ethanol (30 s) and 2% NaClO (3 min), followed by three rinses with sterile water. The sterilized sections were soaked in 2 mL of sterile water and shaken for 5 min in a vortex oscillator. The suspension was streaked on Luria-Bertani (LB) agar medium, and incubated at 28℃ for 24 h. Single colonies were re-streaked three times to obtain purified isolation. Twelve pure bacterial cultures with similar morphology were isolated from three plants taken from the field. The bacterial colonies were yellowish white, mucoid, round, and raised with translucent surfaces on the LB agar plate. Three strains Gxkv1, Gxkv2 and Gxkv3 were selected for further analyses. The 16S rDNA gene (GenBank Accession OR461756, PP094726 and PP109349) were amplified using primer pair 27F/1492R (Frank et al. 2008). Comparing 16S sequences against GenBank showed 99.86%-100% sequence identity to Klebsiella variicola strain (MZ475068) for the three isolates Gxkv1 (1,398/1,398 bp), Gxkv2 (1,398/1,396 bp) and Gxkv3 (1,398/1,398 bp). A multilocus phylogenetic analysis was conducted by neighbor-joining method (1,000 bootstrap values) based on three housekeeping gene sequences of gyrA (GenBank Accession No. OR515493, PP105747, PP105748), rpoB (OR515494, PP105751, PP105752 ) and infB (OR515495, PP105749, PP105750) genes which were amplified by gyrA-A/gyrA-C, CM31b/CM7 and infB867F/infB1819R primer sets, respectively (Rosenblueth et al. 2004). The results of phylogenetic analysis showed the three strains belong to the K. variicola clade. A pathogenicity test was conducted on six healthy 3-month-old dwarf banana plants by spraying 10 mL of bacterial suspensions of Gxkv1 (108 CFU/mL) into the rhizome which wounded with a sterilized needle; another six healthy control plants were sprayed with 10 mL of sterile water. Following inoculation, the plants were placed in a greenhouse at 28-32°C. After 30 days, all inoculated plants showed symptoms similar to those observed in the field, while the control plants remained healthy. Bacteria were successfully reisolated from the symptomatic tissues and identified to be K. variicola by PCR mentioned above. K. variicola has been reported to cause rhizome rot of banana in India (Loganathan et al. 2021), and to cause plantain soft rot in Haiti (Fulton et al. 2021). Besides, previous reports from China only showed K. variicola causing banana sheath rot (Fan et al. 2015, Sun et al. 2023). To our knowledge, this is the first report of bulb rot disease of banana caused by K. variicola in Guangxi Province, China. This finding will provide important information for studying the epidemiology and management of this pathogen.

8.
Science ; 383(6686): 998-1004, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38422151

RESUMO

Maintaining the stability of single-atom catalysts in high-temperature reactions remains extremely challenging because of the migration of metal atoms under these conditions. We present a strategy for designing stable single-atom catalysts by harnessing a second metal to anchor the noble metal atom inside zeolite channels. A single-atom rhodium-indium cluster catalyst is formed inside zeolite silicalite-1 through in situ migration of indium during alkane dehydrogenation. This catalyst demonstrates exceptional stability against coke formation for 5500 hours in continuous pure propane dehydrogenation with 99% propylene selectivity and propane conversions close to the thermodynamic equilibrium value at 550°C. Our catalyst also operated stably at 600°C, offering propane conversions of >60% and propylene selectivity of >95%.

9.
Zhongguo Zhong Yao Za Zhi ; 49(1): 26-38, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38403335

RESUMO

The 29 plant species in the Kadsura genus of the Schisandraceae family are mainly distributed in eastern and southeas-tern Asia. Ten species of plants in this genus are distributed in China, some of which are folk medicinal plants with activating blood circulation, relieving pain, dispelling wind, and dehumidifying effects. Their main constituents are lignans and triterpenes. The current pharmacology and clinical studies have shown that their extracts and constituents have anti-rheumatoid arthritis, liver protection, antioxidation, anti-inflammatory, and other biological activities. The rheumatologic and liver diseases can also be treated with the plants in the clinic. The new chemical constituents reported in the last decade(2012 to date) from the plants of Kadsura genus in China, as well as their pharmacological effects and clinical applications in recent years were reviewed, so as to provide a theoretical basis for further research on the genus.


Assuntos
Medicamentos de Ervas Chinesas , Kadsura , Lignanas , Plantas Medicinais , Lignanas/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , China , Extratos Vegetais , Compostos Fitoquímicos , Etnofarmacologia
10.
J Pediatr Orthop ; 44(4): 236-243, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38298014

RESUMO

OBJECTIVE: Closed or open reduction and spica casting are common treatments for children aged 6 to 18 months, as well as infants aged 0 to 6 months whose harness treatment for developmental dysplasia of the hip (DDH) was unsuccessful. The study aimed to quantify the distance between the femoral head and the acetabulum after closed or open reduction and evaluate the dynamic docking progression of the femoral head using serial hip medical ultrasound. METHODS: We retrospectively reviewed the medical records and hip medial ultrasound images of a consecutive series of patients with DDH who underwent spica casting after reduction and compared images obtained immediately after reduction and at follow-up. The first cast (stage I) was maintained for 2 to 3 months and scheduled for outpatient repeat ultrasound in 4 to 8 weeks. Then the second cast was placed (stage II), lasting for another 2 to 3 months. The triradiate cartilage-femoral head distance (TFD) was measured in the acetabulum coronal mid-sectional plane. The Wilcoxon signed-rank test was used to compare the TFD values. RESULTS: This study included 49 patients. All patients underwent hip medial ultrasound 0 to 3 days after stage I (time 1) and 4 to 8 weeks (time 2) postoperatively, with 24 patients reviewed again 0 to 7 days after stage II. The TFD values in time 1 and time 2 were 6.0 (5.0, 9.0) mm and 5.0 (3.6, 7.0) mm, respectively. There was a statistically significant difference between times 1 and 2 regarding TFD values in 49 close-reduction hips (6.0 vs 5.0 mm, P < 0.001). Similar findings were also observed in 13 open-reduction hips (6.0 vs 5.0 mm, P = 0.023). CONCLUSIONS: Hip medial ultrasonography during the period of cast immobilization after reduction in children with DDH can objectively and quantitatively show the dynamic change of the distance between the femoral head and the acetabulum, and can be used to assess reduction of the hip and progression of femoral head docking. LEVEL OF EVIDENCE: Level II-prognostic study.


Assuntos
Displasia do Desenvolvimento do Quadril , Luxação Congênita de Quadril , Lactente , Criança , Humanos , Luxação Congênita de Quadril/terapia , Luxação Congênita de Quadril/cirurgia , Seguimentos , Resultado do Tratamento , Estudos Retrospectivos , Displasia do Desenvolvimento do Quadril/diagnóstico por imagem , Displasia do Desenvolvimento do Quadril/terapia , Ultrassonografia
11.
Microorganisms ; 12(1)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38257968

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are pervasive organic pollutants in coastal ecosystems, especially in tidal flat wetlands. However, the mechanisms through which PAHs impact the soil bacterial communities of wetlands featuring a simple vegetation structure in the Yellow River Delta (China) remain largely unclear. In this study, we examined soil samples from two sites featuring a single vegetation type (Suaeda salsa) in the Yellow River Delta. Specifically, we investigated the impacts of PAHs on the diversity and composition of soil bacteria communities through high-throughput 16 S rRNA sequencing. PAHs significantly increased the soil organic carbon content but decreased the total phosphorus content (p = 0.02). PAH contamination notably reduced soil bacterial community α diversity (Shannon index) and ß diversity. Furthermore, PAHs significantly altered the relative abundance of bacterial phyla, classes, and genera (p < 0.05). Specifically, PAHs increased the relative abundance of the bacterial phyla Acidobacteriota and Gemmatimonadota (p < 0.05), while decreasing the relative abundance of Bacteroidota, Desulfobacterota, and Firmicutes compared to the control wetland (p < 0.05). Moreover, PAHs and certain soil properties [total nitrogen (TN), soil organic carbon (SOC), total phosphorus (TP), and total salt (TS)] were identified as key parameters affecting the community of soil bacteria, with the abundance of specific bacteria being both negatively and positively affected by PAHs, SOC, and TN. In summary, our findings could facilitate the identification of existing environmental problems and offer insights for improving the protection and management of tidal flat wetland ecosystems in the Yellow River Delta of China.

12.
Sci Total Environ ; 912: 168878, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38029973

RESUMO

Plant diversity and soil microbial diversity are closely related, and they maintain the health and stability of terrestrial ecosystems. As a hotspot region of global biodiversity research, both air temperature and precipitation of the Qinghai-Xizang Plateau tend to increase in future. Based on an overview of the responses of grassland/alpine ecosystems to seasonal asymmetric warming and increased precipitation worldwide, we elaborated the advancements and uncertainties on the responses of plant diversity and soil microbial diversity to warming and increased precipitation in alpine grasslands on the Qinghai-Xizang Plateau. The future research focus of plant diversity and soil microbial diversity in the alpine grasslands of the Qinghai-Xizang Plateau under climate warming and increased precipitation was proposed. Generally, previous studies found that the responses of plant species diversity and soil microbial species diversity to warming and increased precipitation differed between alpine meadows and alpine steppes, but few studies focused on their responses to warming and increased precipitation in alpine desert steppes. Previous studies mainly focused on species diversity, although phylogenetic and functional diversities are also important aspects of biodiversity. Previous studies mainly explained responses of plant diversity and soil microbial diversity to warming and increased precipitation based on niche theory, although neutral theory is also the other important mechanism in regulating biodiversity. Moreover, previous studies almost ignored the coupling relationship between plant diversity and soil microbial diversity. Therefore, the following four aspects need to be strengthened, including the responses of plant diversity and soil microbial diversity to warming and increased precipitation in alpine desert steppes, the responses of plant and soil microbial phylogenetic diversity and functional diversity to warming and increased precipitation, combining the niche theory and neutral theory to examining the mechanism of biodiversity, and the coupling relationships between plant diversity and soil microbial diversity under warming and increased precipitation.


Assuntos
Ecossistema , Pradaria , Solo , Microbiologia do Solo , Filogenia , Plantas
13.
Nephrol Dial Transplant ; 39(2): 251-263, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-37458807

RESUMO

BACKGROUND: To explore the cut-off values of haemoglobin (Hb) on adverse clinical outcomes in incident peritoneal dialysis (PD) patients based on a national-level database. METHODS: The observational cohort study was from the Peritoneal Dialysis Telemedicine-assisted Platform (PDTAP) dataset. The primary outcomes were all-cause mortality, major adverse cardiovascular events (MACE) and modified MACE (MACE+). The secondary outcomes were the occurrences of hospitalization, first-episode peritonitis and permanent transfer to haemodialysis (HD). RESULTS: A total of 2591 PD patients were enrolled between June 2016 and April 2019 and followed up until December 2020. Baseline and time-averaged Hb <100 g/l were associated with all-cause mortality, MACE, MACE+ and hospitalizations. After multivariable adjustments, only time-averaged Hb <100 g/l significantly predicted a higher risk for all-cause mortality {hazard ratio [HR] 1.83 [95% confidence interval (CI) 1.19-281], P = .006}, MACE [HR 1.99 (95% CI 1.16-3.40), P = .012] and MACE+ [HR 1.77 (95% CI 1.15-2.73), P = .010] in the total cohort. No associations between Hb and hospitalizations, transfer to HD and first-episode peritonitis were observed. Among patients with Hb ≥100 g/l at baseline, younger age, female, use of iron supplementation, lower values of serum albumin and renal Kt/V independently predicted the incidence of Hb <100 g/l during the follow-up. CONCLUSION: This study provided real-world evidence on the cut-off value of Hb for predicting poorer outcomes through a nation-level prospective PD cohort.


Assuntos
Falência Renal Crônica , Diálise Peritoneal , Peritonite , Humanos , Feminino , Estudos Prospectivos , Diálise Peritoneal/efeitos adversos , Diálise Renal/efeitos adversos , Hemoglobinas , Falência Renal Crônica/epidemiologia , Peritonite/etiologia , Estudos Retrospectivos
14.
BMC Infect Dis ; 23(1): 895, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38124038

RESUMO

BACKGROUND: This work aimed to study natural humoral immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: Chemiluminescent immunoassay (CLIA) was used to detect the neutralizing antibody (Nabs) and IgG. RESULTS: Nabs peaked on days 57-96 after symptom onset and remained detected on days 97-132. The Nabs in the 32 patients who were dynamically monitored showed four changing patterns. The titers of Nabs and IgG were correlated, and three modes of relationship were found between them. CONCLUSIONS: Nabs showed a regular change in the course of coronavirus disease 2019 (COVID-19). The detection of Nabs is very important for monitoring the course of COVID-19 and predicting the strength of antibody protection.


Assuntos
COVID-19 , Vacinas , Humanos , COVID-19/diagnóstico , Anticorpos Neutralizantes , SARS-CoV-2 , Imunoglobulina G
15.
J Org Chem ; 88(23): 16547-16555, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37971809

RESUMO

A photocatalytic three-component reaction of a nitroarene, a thiophenol, and a ketone for the synthesis of multifunctional diaryl sulfides was reported using a nitro group as the nitrogen source and thiophenol as the sulfur source. Thiophenol also serves as a proton donor to reduce nitroarene to arylamine as a key intermediate for the formation of C-N and C-S bonds. Good functional group tolerance and mild reaction conditions make this method have practical synthetic value for diversified multifunctional diaryl sulfides.

16.
JACS Au ; 3(11): 3141-3154, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38034970

RESUMO

Selective oxidation of C-H bonds under mild conditions is one of the most important and challenging issues in utilization of energy-related molecules. Molybdenum oxide nanostructures containing Mo5+ species are effective for these reactions, but the accurate identification of the structure of active Mo5+ species and the catalytic mechanism remain unclear. Herein, unsaturated penta-coordinated Mo5c5+ with a high fraction in MoOx fabricated by the hydrothermal method were identified as the active sites for low-temperature oxidation of dimethyl ether (DME) by the deep correlation of characterizations, density functional theory calculations, and activity results, giving a methyl formate selectivity of 96.3% and DME conversion of 12.5% at unreported 110 °C. Low-temperature electron spin resonance (ESR) and quasi in situ X-ray photoelectron spectra (XPS) with the designed experiments confirm that the Mo5c5+ species can be formed in situ. Molybdenum located at the pentachronic site is preferable to significantly promote the oxidation of the C-H bond in CH3O* at lower temperatures.

17.
Plant Dis ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37923973

RESUMO

Syzygium grijsii is an evergreen shrub belonging to the family Myrtaceae, and widely cultivated in southern China as an ornamental medicinal plant. In May 2022, anthracnose symptoms were observed on leaves of S. grijsii planted in a nursery (N22°55'46″, E108°22'11″) in Nanning, Guangxi Province, China. More than 30% of leaves were infected. Initially, irregular brown spots (1 to 2 mm in diameter) formed on the leaves, with a slight depression in the center, then expanded into large, dark-brown lesions. In severe infections, lesions coalesced and covered the entire leaf, causing wilt and fall off the plant. To identify the pathogen, 30 diseased leaves were collected from five plants. Leaf tissues (5 × 5 mm) were cut from the infected margins, surface sterilized (75% ethanol 10 s, 2% NaClO 5 min, rinsed three times with sterile water), then placed on potato dextrose agar (PDA), and incubated at 28℃ in darkness. After 5 days, 16 fungal isolates with similar morphology were obtained from 30 plated tissues. Colonies on PDA were abundant with grayish-white fluffy mycelia, and yellowish-white on the back. Conidia were one-celled, hyaline, smooth-walled, cylindrical with narrowing at the center, blunt at the ends, and ranged from 11.35 to 22.14 × 4.88 to 7.67 µm (n=100). Morphological characteristics of the isolates were similar to the descriptions of Colletotrichum sp. (Prihastuti et al. 2009). Five representative isolates (Cs34, Cs31, Cs32, Cs33 and Cs35), which were preserved in the Guangxi Key Laboratory of Biology for Crop Diseases and Insect Pests, were selected for molecular identification. The ITS (Nos. OQ618199, OR539576 to OR539579), TUB2 (Nos. OQ630972, OR545076 to OR545079), ACT (Nos. OQ685919, OR545060 to OR545063), CHS-1 (Nos. OQ685917, OR545068 to OR545071), GAPDH (Nos. OQ685916, OR545072 to OR545075), and CAL (Nos. OQ685918, OR545064 to OR545067) sequences showed >99% identity to those of Colletotrichum siamense ex-type culture ICPM 18578 (Nos. JX010171, JX009924, JX009714 and JX009518) and strain C1315.2 (Nos. JX009865 and JX010404) in GenBank. Multigene phylogenetic analyses (ITS, TUB, ACT, CHS-1, GAPDH, and CAL) using the Maximum likelihood method indicated that the 5 isolates were clustered with C. siamense. To perform pathogenicity tests, three one-year-old healthy S. grijsii plants were inoculated with conidial suspension (1 × 106 conidia/ml) of isolate Cs34 by brushing gently with a soft paintbrush, each plant was inoculated with 3 leaves. The same number of plants were inoculated with sterile water as control, and pathogenicity tests were performed three times. All plants were kept in an artificial climatic box at 28℃, with a 90% humidity and a 12 h light/dark cycle. Similar symptoms to those of the field were observed on all inoculated leaves after 5 days, whereas controls remained symptomless. Reisolated fungi from the diseased leaves were confirmed to be C. siamense by morphology and molecular characterization, confirming Koch's postulates. C. siamense has been reported causing anthracnose on Crinum asiaticum (Khoo et al. 2022) in Malaysia, and Erythrina crista-galli in China (Li et al. 2021). To our knowledge, this is the first report of C. siamense causing anthracnose on S. grijsii in China. The results of pathogen identification provide crucial information for control strategies of the disease.

18.
J Invest Surg ; 36(1): 2278191, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37970828

RESUMO

PURPOSE: To compare the effectiveness, safety and cost-effectiveness of endoscopic submucosal dissection (ESD) with transanal endoscopic microsurgery (TEM) in early rectal neuroendocrine tumor (RNET) patients. This article will provide reliable evidence for surgeons in regards to clinical decision-making. METHODS: Systematic literature retrieval was performed in Pubmed, Embase and Cochrane database from 2013/4/30 to 2023/4/30. Methodology validation was performed by using the Newcastle-Ottawa Scale (NOS). Data-analysis was conducted by using the Review manager version 5.3 software. RESULTS: A total of three retrospective studies were included in our meta-analysis. All eligible studies were considered to be high quality. By comparing baseline characteristics between TEM and ESD, patients in the TEM group seemed to be characterized by a larger tumor size and lower tumor level, even though no statistical significance was found. Clear statistical significance favoring TEM was identified in terms of R0 resection rate, procedure time and hospital stay. No statistical significance was found in terms of recurrence rate, adverse events rate and additional treatment rate. CONCLUSIONS: Compared with ESD, TEM was a more effective treatment modality for early RNET patients; it was associated with a relatively higher R0 resection rate and a similar degree of safety. However, the relatively higher cost and complicated manipulation restricted the promotion of TEM. Surgeons should opt for TEM as a primary treatment in patients with a larger tumor size and deeper degree of tumorous infiltration if the financial condition and hospital facility permit.


Assuntos
Ressecção Endoscópica de Mucosa , Tumores Neuroendócrinos , Neoplasias Retais , Microcirurgia Endoscópica Transanal , Humanos , Microcirurgia Endoscópica Transanal/efeitos adversos , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Tumores Neuroendócrinos/cirurgia , Tumores Neuroendócrinos/etiologia , Estudos Retrospectivos , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia
19.
Phys Chem Chem Phys ; 25(41): 28086-28093, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37817676

RESUMO

The competition between E2 and SN2 reactions is essential in organic chemistry. In this paper, the reaction mechanism of F- + CH3CH2Cl is investigated utilizing direct dynamics simulations, and unravel how the collision energy (Ecoll) and the leaving group affect the competition between SN2 and E2 in the F- + CH3CH2Y (Y = Cl and Br) reactions. Simulation results for F- + CH3CH2Cl reaction show that the anti-E2 channel is dominant, but with the increase of Ecoll from 0.04 to 1.9 eV the branching ratio of the anti-E2 pathway significantly decreases by 21%, and the SN2 pathway becomes more important. A transition from indirect to direct reaction has been revealed when Ecoll is increased from 0.04 to 1.90 eV. At lower Ecoll, a large ratio of indirect events occurs via a long-lived hydrogen-bonded complex, and as the collision energy is increased, the lifetimes of the hydrogen-bonded complexes are shortened, due to an initial faster relative velocity. The simulation results of F- + CH3CH2Cl are further compared with the F- + CH3CH2Br reaction at Ecoll of 0.04 eV. Changing the leaving group from Cl to Br drastically suppresses the indirect events of anti-E2 with a branching ratio decreasing from 0.46 to 0.36 due to the mass effect, and promotes direct rebound mechanism resulting from a looser transition state geometry caused by varied electronegativity.

20.
J Mol Histol ; 54(6): 689-702, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37857924

RESUMO

Alpha-calcitonin gene-related peptide (αCGRP) and substance P (SP) are functionally correlated sensory neuropeptides deeply involved in bone homeostasis. However, they are usually studied individually rather than as an organic whole. To figure out whether they are interdependent, we firstly recorded the real-time αCGRP and SP levels in aging bone and healing fracture, which revealed a moderate to high level of αCGRP coupled with a low αCGRP/SP ratio in an anabolic state, and a high level of αCGRP coupled with a high αCGRP/SP ratio in a catabolic state, suggesting the importance of αCGRP/SP ratio in driving aging and healing scenarios. During facture healing, increase in αCGRP/SP ratio by adding αCGRP led to better callus formation and faster callus remodeling, while simultaneous addition of αCGRP and SP resulted in hypertrophic callus and delayed remodeling. The characteristics in inflammation and osteoclast activation further confirmed the importance of high αCGRP/SP ratio during catabolic bone remodeling. In vitro assays using different mixtures of αCGRP-SP proved that the osteogenic potential of the mixtures depended mostly on αCGRP, while their effects on osteoclasts and neutrophils relied on both peptides. These results demonstrated that αCGRP and SP were spatiotemporally interdependent. The αCGRP/SP ratio may be more important than the dose of a single neuropeptide in managing age-related and trauma-related bone diseases.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina , Substância P , Substância P/farmacologia , Osso e Ossos/metabolismo , Osteogênese
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