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1.
Front Oncol ; 14: 1320020, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444677

RESUMO

Background: Colorectal cancer (CRC) is considered the most prevalent synchronous malignancy in patients with gastric cancer. This large retrospective study aims to clarify correlations between gastric histopathology stages and risks of specific colorectal neoplasms, to optimize screening and reduce preventable CRC. Methods: Clinical data of 36,708 patients undergoing gastroscopy and colonoscopy from 2005-2022 were retrospectively analyzed. Correlations between gastric and colorectal histopathology were assessed by multivariate analysis. Outcomes of interest included non-adenomatous polyps (NAP), conventional adenomas (CAs), serrated polyps (SPs), and CRC. Statistical analysis used R version 4.0.4. Results: Older age (≥50 years) and Helicobacter pylori infection (HPI) were associated with increased risks of conventional adenomas (CAs), serrated polyps (SPs), non-adenomatous polyps (NAP), and colorectal cancer (CRC). Moderate to severe intestinal metaplasia specifically increased risks of NAP and CAs by 1.17-fold (95% CI 1.05-1.3) and 1.19-fold (95% CI 1.09-1.31), respectively. For CRC risk, low-grade intraepithelial neoplasia increased risk by 1.41-fold (95% CI 1.08-1.84), while high-grade intraepithelial neoplasia (OR 3.76, 95% CI 2.25-6.29) and gastric cancer (OR 4.81, 95% CI 3.25-7.09) showed strong associations. More advanced gastric pathology was correlated with progressively higher risks of CRC. Conclusion: Precancerous gastric conditions are associated with increased colorectal neoplasm risk. Our findings can inform screening guidelines to target high-risk subgroups, advancing colorectal cancer prevention and reducing disease burden.

2.
Nanotechnology ; 35(7)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37976546

RESUMO

In this study, we conducted molecular dynamic simulations to investigate the thermal expansion behavior of Janus MoSSe nanotubes. We focused on understanding how the intrinsic strain in these nanotubes affects their thermal expansion coefficient (TEC). Interestingly, we found that Janus MoSSe nanotubes with sulfur (S) on the outer surface (MoSeS) exhibit a different intrinsic strain compared to those with selenium (Se) on the outer surface (MoSSe). In light of this observation, we explored the influence of this intrinsic strain on the TEC of the nanotubes. Our results revealed distinct trends for the TEC along the radial direction (TEC-r) and the axial direction (TEC-lx) of the MoSSe and MoSeS nanotubes. The TEC-rof MoSeS nanotubes was found to be significantly greater than that of MoSSe nanotubes. Moreover, the TEC-lxof MoSeS nanotubes was smaller than that of MoSSe nanotubes. Further analysis showed that the TEC-rof MoSeS nanotubes decreased by up to 37% as the radius increased, while that of MoSSe nanotubes exhibited a slight increase with increasing radius. On the other hand, the TEC-lxof MoSeS nanotubes increased by as much as 45% with increasing radius, whereas that of MoSSe nanotubes decreased gradually. These opposite tendencies of the TECs with respect to the radius were attributed to the presence of intrinsic strain within the nanotubes. The intrinsic strain was found to play a crucial role in inducing thermally induced bending and elliptization of the nanotubes' cross-section. These effects are considered key mechanisms through which intrinsic strain influences the TEC. Overall, our study provides valuable insights into the thermal stability of Janus nanotubes. By understanding the relationship between intrinsic strain and the thermal expansion behavior of nanotubes, we contribute to the broader understanding of these materials and their potential applications.

3.
J Insect Sci ; 23(6)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38006418

RESUMO

Insect gut bacteria play an essential role in the nutritional metabolism, growth, and development of insects. Grasshoppers (Orthoptera) are cellulose-rich plant-feeding pests. Although the biological potential of grasshopper gut microorganisms to assist cellulose decomposition is well established, microbial resources for efficient degradation of cellulose biomass are still scarce and need to be developed. In this study, we used selective media to isolate cellulose-degrading bacteria from the intestines of Atractomorpha sinensis, Trilophidia annulata, Sphingonotus mongolicus, and Calliptamus abbreviatus. Phylogenetic analysis based on the maximum likelihood method using 16S rDNA sequencing sequences to identify bacteria revealed the isolation of 11 strains belonging to 3 genera, including Klebsiella, Aeromonas, and Bacillus. The degradability of the isolates to cellulose was then determined by the DNS colorimetric method, and the results showed that Bacillus had the highest degradation rate. The elucidation of microbial cellulose degradation capacity in grasshoppers not only contributes to the understanding of multiple plant-insect-microbe interactions, but also provides a valuable microbial resource for solving the biomass conversion of cellulose species problem.


Assuntos
Gafanhotos , Animais , Gafanhotos/metabolismo , Filogenia , Celulose/metabolismo , Bactérias/genética , Biomassa
4.
PLoS One ; 18(10): e0293466, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37878642

RESUMO

Gastric cancer (GC) is a prominent global health issue, as it ranks as the fifth most prevalent type of cancer and the fourth most significant cause of cancer-related mortality worldwide. Although H. pylori is known to play a role in the development of GC, genetic factors also play a role in its onset and progression. Recent studies have shown that genetic polymorphisms are strongly associated with the development of GC and that certain single nucleotide polymorphisms (SNPs) can be used as biomarkers for early diagnosis and prevention. Epigenetic disturbances, such as DNA methylation, are involved in the development of GC, and mutations in the DNA methyltransferase (DNMT) gene have been found to increase the risk of GC. However, previous findings on the association between DNMTs SNPs and GC risk have been inconsistent. In this study, an updated meta-analysis of three well-studied and controversial DNMTs polymorphic loci, DNMT1 rs16999593, DNMT3A rs1550117 and DNMT3B rs1569686, was performed to provide more reliable results. It was found that DNMT1 rs16999593 was not associated with GC, DNMT3A rs1550117 may have a positive association with GC risk, and DNMT3B rs1569686 may be a protective factor for GC. These findings may provide valuable information for early diagnosis and prevention of GC, but further studies are needed to confirm these results.


Assuntos
Predisposição Genética para Doença , Neoplasias Gástricas , Humanos , Genótipo , DNA Metiltransferase 3A , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferase 1/genética , Polimorfismo de Nucleotídeo Único , Metilação de DNA , Neoplasias Gástricas/genética , Fatores de Proteção
5.
Zootaxa ; 5270(3): 593-598, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37518148

RESUMO

A new species of the genus Hamodes Guenée, 1852, Hamodes zhipengi sp. nov. is described and illustrated from China. The species resembles H. pseudobutleri Wei & Wang, 2019 but differs in wings ground colour; and male genitalia with differently shaped valvae, ampullae and armature of vesica. DNA barcode of the new species and relatives are deposited in GenBank. The holotype is deposited in the Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou.


Assuntos
Lepidópteros , Mariposas , Masculino , Animais , Lepidópteros/genética , Mariposas/genética , China , Universidades , Genitália
6.
Zootaxa ; 5270(1): 124-132, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37518173

RESUMO

A new species Eterusia sinoraja Huang & Horie sp. n. is described from western Sichuan Province, western China. The comparison is made with the reminiscent E. raja Moore, 1859 from northeastern India. The adult and genitalia of both sexes of the aforementioned taxa are illustrated.


Assuntos
Lepidópteros , Mariposas , Masculino , Feminino , Animais , Genitália , China
7.
Zootaxa ; 5315(3): 251-263, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37518604

RESUMO

The name Striatochrista nom. n. is introduced as replacement for Striatella Volynkin & S.-Y. Huang, 2019. A new genus, Letrasilta S.-Y. Huang & Volynkin gen. n. is erected to include the Striatella cernyi species-group with the new species, L. ratnasambhava S.-Y. Huang, Volynkin & Yin sp. n. from Xizang, southwestern China designated as the type species. Based on the molecular phylogenetic analysis, the new genus is found to be sister to the clade (Aberrasine + ((Indiania + Idopterum) + Striatochrista nom. n.)) but is distinguished from all the relevant genera by the unique genitalia features. Letrasilta cernyi (Volynkin, 2018) comb. n. is also reported from India for the first time. Adults and genitalia of the aforementioned taxa are illustrated. A checklist of the genus Striatochrista is also provided.


Assuntos
Mariposas , Filogenia , Animais , China , Genitália/anatomia & histologia , Mariposas/anatomia & histologia , Mariposas/classificação , Mariposas/genética , Genes de Insetos/genética , Especificidade da Espécie
8.
Int J Biol Macromol ; 247: 125504, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37356692

RESUMO

Preventing wound infection is a major challenge in biomedicine. Conventional wound dressings often have poor moisturizing and antimicrobial properties unfavorable for wound healing. In this study, we prepared a multifunctional electrospun nanofiber dressing (PCQX-M) containing xyloglucan, quaternized chitosan, Polyvinyl alcohol, and collagen. By applying the concept of wet healing, xyloglucan and quaternized chitosan polysaccharides with excellent water solubility were employed to improve the absorption and moisturizing properties and maintain a moist microenvironment for the wound healing process. PCQX-M demonstrated high mechanical, thermodynamic, and biocompatible properties, providing suitable healing conditions for wounds. In addition, PCQX-M showed exceptional antibacterial properties and a potential inhibitory effect on the growth of microorganisms in infected wounds. More intriguingly, the restorative healing effect was investigated on a mouse model of whole skin injury infected with Staphylococcus aureus. Wound healing, collagen deposition, and immunofluorescence results showed that PCQX-M significantly promoted cell proliferation and angiogenesis at the injury site and facilitated the healing of the infected wound. Our study suggests that PCQX-M has excellent potential for clinical application in infected wound healing.


Assuntos
Quitosana , Nanofibras , Infecção dos Ferimentos , Camundongos , Animais , Quitosana/farmacologia , Cicatrização , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bandagens/microbiologia , Colágeno/farmacologia , Infecção dos Ferimentos/tratamento farmacológico
9.
ACS Omega ; 8(18): 16251-16262, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37179598

RESUMO

To eliminate internal defects of grains developed during melt-cast charging, the formation mechanism and the trend of crystal morphology of internal defects of 2,4,6-trinitrotoluene and 2,4-dinitroanisole-based melt-cast explosives under different process conditions were simulated. The effects of solidification treatment on melt-cast explosive molding quality were investigated by combining pressurized feeding, head insulation, and water bath cooling. The single pressurized treatment technology results showed that grains were exposed to layer-by-layer solidification from outside to inside, resulting in V-shaped shrink areas of the contract cavity in the core. The defect area was proportional to the treatment temperature. However, the combination of treatment technologies, such as head insulation and water bath cooling, promoted longitudinal gradient solidification of the explosive and controllable migration of its internal defects. Moreover, the combined treatment technologies effectively improved the heat transfer efficiency of the explosive with the help of a water bath to reduce the solidification time, thus achieving highly efficient equal-material manufacturing of microdefect or zero-defect grains.

10.
Zhongguo Gu Shang ; 35(10): 971-6, 2022 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-36280415

RESUMO

OBJECTIVE: To analyze the clinical effect of rotator cuff repair and small incision rotator cuff repair under the total arthroscopy in elderly patients with rotator cuff injury. METHODS: A total of 60 elderly patients with rotator cuff injury from January 2017 to November 2018 were selected as the research objects, including 37 males and 23 females;aged from 61 to 77 years old with an average of (63.45±12.34) years old;disease duration ranged from 6 to 12 months, with an average of (5.32±1.02 ) months;29 cases on the left side and 31 cases on the right side. Among them, 30 patients underwent total arthroscopic rotator cuff repair (observation group), 30 patients underwent small-incision rotator cuff repair(control group). The scores of University of California, Los Angeles(UCLA) shoulder rating scale, before and after surgery in the two groups were observed and recorded. The American Shoulder and Elbow Surgeons(ASES) score, Constant-Murley score, shoulder flexion range of motion, external rotation range of motion, abduction range of motion, visual analogue scale(VAS) within 72 hours after surgery, as well as the complcations were compared. RESULTS: The postoperative UCLA score, ASES score and Constant-Murley score between two groups were significantly higher than those before operation (P<0.05). There was no significant difference in postoperative UCLA, ASES and Constant-Murley score between two groups (P>0.05). The shoulder flexion range of motion, external rotation range of motion and abduction range of motion between two groups were significantly higher than those before operation (P<0.05). There was no significant difference between the two groups after operation (P>0.05). The VAS at 24, 48 and 72 h after operation in observation group were significantly lower than those in control group (P<0.05). The total incidence of complications in observation group(13.33%, 4/30) was sinificantly lower(P<0.05)than that in control group(33.33%, 10/30). CONCLUSION: Total arthroscopic rotator cuff repair and small incision rotator cuff repair can improve the shoulder function after rotator cuff injury in elderly, but the degree of pain and complications within 72 hours after total arthroscopic rotator cuff repair are significantly better than small incision rotator cuff repair, which can be selected according to the clinical situation and needs of patients.


Assuntos
Lesões do Manguito Rotador , Articulação do Ombro , Masculino , Feminino , Humanos , Idoso , Pessoa de Meia-Idade , Lesões do Manguito Rotador/cirurgia , Artroscopia , Manguito Rotador/cirurgia , Articulação do Ombro/cirurgia , Resultado do Tratamento , Dor
11.
Zootaxa ; 5168(5): 589-594, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-36101261

RESUMO

A new species of the genus Neopheosia Matsumura, 1920, N. pseudofasciata sp. nov. is described and illustrated from Fujian province. The species resembles N. fasciata (Moore, 1888) but differs in a forewing pattern in M3 cell; diagnostic differences are observed in genitalia characters as well. DNA barcode data of the new species and its relatives are deposited in GenBank. A key to the Neopheosia species based on morphology is presented. The holotype is deposited in the Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou.


Assuntos
Lepidópteros , Animais , China , Genitália , Humanos , Parques Recreativos , Universidades
12.
Zookeys ; 1114: 167-182, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761705

RESUMO

A brief taxonomic review of the lithosiinid genus Ammathella Volynkin, 2019 is presented. Three new species of the genus Ammathella Volynkin, 2019 are described from Motuo County, southeast Xizang: A.longicornuta S.-Y. Huang, Yin & Volynkin, sp. nov., A.lhoba S.-Y. Huang, Yin & Volynkin, sp. nov., and A.monpa S.-Y. Huang, Yin & Volynkin, sp. nov. A key to the species of the genus is provided. Adults and genitalia of both sexes are illustrated.

13.
China Tropical Medicine ; (12): 1078-2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-974026

RESUMO

@#Abstract: Objective To study the characteristics and diagnostic efficacy of Rose-Bengal plate agglutination test (RBPT), standard-tube agglutination test (SAT) and enzyme-linked immunosorbent assay (ELISA) in the diagnosis of brucellosis. Methods A total of 489 suspected brucellosis patients with complete records, who admitted to Xing'anmeng People's Hospital from March 2020 to May 2021, were selected as the subjects. The diagnostic value of SAT, RBPT and ELISA for brucellosis was analyzed with exposure history + clinical symptoms + serological test/brucellosis isolation and culture as the gold standard. Results Of the 489 suspected patients, 183 (37.42%) were diagnosed with brucellosis, while 234 (47.85%), 148 (30.27%) and 195 (39.88%) were positive by RBPT, ELISA and SAT, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of RBPT in the diagnosis of brucellosis were 95.08%, 80.39%, 74.36%, 96.47%, and 85.89%, respectively; the values of the above parameters for ELISA were 78.69%, 98.69%, 97.30%, 88.56%, and 91.21%, respectively; those values of SAT were 98.36%, 95.10%, 92.31%, 98.98%, and 96.32%, respectively. The sensitivity of RBPT was significantly higher than ELISA, but the specificity and accuracy were significantly lower than ELISA (all P<0.05). The sensitivity and accuracy of SAT diagnosis were significantly higher than ELISA, but the specificity was significantly lower than ELISA (all P<0.05). There was no significant difference between SAT and RBPT in the sensitivity of diagnosis, but the specificity and accuracy were significantly higher than those of RBPT (P<0.05). Conclusion RBPT and SAT have high sensitivity in diagnosis of brucellosis, while ELISA has high specificity in diagnosis. RBPT with high sensitivity and convenient operation can be used for primary screening in field detection, and then the other two methods can be used for rechecking, so as to further improve the efficiency and accuracy of diagnosis of brucellosis.

14.
Sci Rep ; 11(1): 13725, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215807

RESUMO

Enterobacteria that produce extended-spectrum ß-lactamase (ESBL) such as Escherichia coli (E. coli) are common in our environment and known to cause serious health implications in humans and animals. ß-lactam antibiotics such as penicillins, cephalosporins and monobactams are the most commonly used anti-bacterials in both humans and animals, however, Gram negative bacteria (such as E. coli) that produces extended-spectrum ß-lactamases (ESBLs) have the ability to hydrolyze most ß-lactams therefore making them resistant to ß-lactam antibiotics. Recent extensive researches on the epidemiology and genetic characteristics of extended-spectrum ß-lactamase (ESBL)-producing E. coli reported the existence of ESBL-producing E. coli in humans, companion animals and poultry. Therefore, this experiment was performed to investigate the prevalence and genetic characteristics of ß-lactamase producing E. coli isolated from beef cattle farms in the Sichuan-Chongqing circle of China. Phenotypic confirmation of ESBL-producing E. coli was performed using the double disk synergy test. Polymerase Chain Reaction (PCR) was used to detect blaCTX-M, blaSHV and blaTEM gene codes, then after, isolates were divided into different phylogenetic groups and multi-locus sequence typing (MLST). The results showed that out of the 222 E. coli strains isolated from the beef cattle, 102 strains showed ESBL phenotypes. The PCR results showed that blaCTX-M was the predominant ESBL gene identified among the E. coli strains with 21 (9.5%) isolates having this gene, followed by blaSHV which was found in 18 (8.1%) isolates. The majority of these ESBL positive isolates were assigned to phylogroup A (19.8%) followed by phylogroup B1 (13.5%). In addition, from the MLST results on ESBL positive isolates (n = 30) we identified 19 STs, ST398 (ST398cplx) and ST7130 which were the prevalent population (20%). In conclusion, the high prevalence of CTX-M, and SHV in the study confirmed its association with E. coli infection; therefore, this calls for health concerns on ESBL-producing E. coli. As far as we know, this is the first comprehensive research report relating to ESBL-producing E. coli incidence in Chinese beef cattle.


Assuntos
Bovinos/microbiologia , Escherichia coli/enzimologia , beta-Lactamases/genética , Animais , China , Escherichia coli/genética , Carne Vermelha/microbiologia
15.
J Enzyme Inhib Med Chem ; 36(1): 1622-1631, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34284695

RESUMO

Some methoxy-, hydroxyl-, pyridyl-, or fluoro-substituted 3,5-bis(arylidene)-4-piperidones (BAPs) could reduce inflammation and promote hepatoma cell apoptosis by inhibiting activation of NF-κB, especially after introduction of trifluoromethyl. Herein, a series of trifluoromethyl-substituted BAPs (4-30) were synthesised and the biological activities were evaluated. We successfully found the most potential 16, which contains three trifluoromethyl substituents and exhibits the best anti-tumour and anti-inflammatory activities. Preliminary mechanism research revealed that 16 could promote HepG2 cell apoptosis in a dose-dependent manner by down-regulating the expression of Bcl-2 and up-regulating the expression of Bax, C-caspase-3. Meanwhile, 16 inhibited activation of NF-κB by directly inhibiting the phosphorylation of p65 and IκBα induced by LPS, together with indirectly inhibiting MAPK pathway, thereby exhibiting both anti-hepatoma and anti-inflammatory activities. Molecular docking confirmed that 16 could bind to the active sites of Bcl-2, p65, and p38 reasonably. The above results suggested that 16 has enormous potential to be developed as a multifunctional agent for the clinical treatment of liver cancers and inflammatory diseases.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , NF-kappa B/antagonistas & inibidores , Piperidonas/farmacologia , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Simulação de Acoplamento Molecular , Estrutura Molecular , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Piperidonas/síntese química , Piperidonas/química , Relação Estrutura-Atividade
16.
Sci Total Environ ; 772: 145355, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578146

RESUMO

Zeolite has a high adsorption capacity for heavy metals, but it is difficult to separate from the medium because of its small particle size. In this study, magnetic zeolite was synthesized from natural, low-grade molybdenum ore by adding nano ferroferric oxide (saturation magnetization 83.43 emu/g) directly in the hydrothermal synthesis process, which was used to adsorb cadmium from wastewater. The results of scanning electron microscopy showed that the nano ferroferric oxide was adhered to the surface of the zeolite to make it magnetic. The vibrating sample magnetometer showed that the larger the amount of nano ferroferric oxide added, the higher the saturation magnetization of the magnetic zeolite. The saturation magnetization of the magnetic zeolite with a loading proportion of 25% was 18.18 emu/g with a specific surface area of 459.8 m2/g. The adsorption experiments showed that when the pH value is greater than 4, the adsorption capacity of magnetic zeolite is high and stable, and the theoretical maximum adsorption capacity is 204.2 mg Cd/g. Na+ and Ca2+ have different inhibitory functions on the adsorption capacity. The mapping graphs showed that cadmium is captured by the magnetic zeolite after contact with cadmium, and XRD confirmed the presence of cadmium oxide in the magnetic zeolite after adsorption, XPS and EDS results indicated that ion exchange is one of the main mechanisms of cadmium adsorption by magnetic zeolites, and electrostatic adsorption may also have a contribution.

17.
Microbiol Resour Announc ; 9(49)2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33272984

RESUMO

Serratia marcescens strain ZZCCN01 was isolated from the cardiac blood of a dead beef cow with a lung infection and a foam-like secretion from the nostril. Here, we introduce the 5.1-Mb draft genome sequence, which comprises 105 scaffolds, and the corresponding annotation.

18.
Chem Commun (Camb) ; 56(69): 10030-10033, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32728678

RESUMO

Chiral phosphoric acid-catalyzed asymmetric aldehyde prenylation has been established using an α,α-dimethyl allyl boronic ester. The transformation provides expedient access to a wide array of aryl, heteroaryl, aryl-substituted alkenyl and primary and secondary aliphatic homoprenyl alcohols with excellent asymmetric induction. The utility of this asymmetric catalysis strategy has been demonstrated through a short and efficient total synthesis of the two natural products (-)-rosiridol and (-)-bifurcadiol.


Assuntos
Aldeídos/química , Produtos Biológicos/química , Diterpenos/síntese química , Álcoois/síntese química , Álcoois/química , Produtos Biológicos/síntese química , Boro/química , Catálise , Diterpenos/química , Ácidos Fosfóricos/química , Prenilação , Estereoisomerismo
19.
Chemistry ; 26(45): 10259-10264, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32432354

RESUMO

Brønsted acid-catalyzed general Petasis allylation and isoprenylation of unactivated ketones were developed by using o-hydroxyaniline and the corresponding pinacolyl boronic esters. This robust methodology provided access to a broad variety of quaternary homoallylic amines and dienyl amines in high yields, proved to be applicable to a gram-scale synthesis, and allowed the synthesis of a potentially bioactive quaternary homoallylic aminodiol.

20.
J Appl Toxicol ; 40(5): 631-642, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31922269

RESUMO

Iron oxide nanoparticles are nanomaterials that are used extensively in the biomedical field, but they are associated with adverse effects, including mitochondrial toxicity. Mitochondrial homeostasis is achieved through dynamic stability based on two sets of antagonistic balanced processes: mitochondrial biogenesis and degradation as well as mitochondrial fission and fusion. In this study, we showed that PEG-COOH-coated Fe3 O4 (PEG-Fe3 O4 ) nanoparticles induced mitochondrial instability in dendritic cells (DCs) by impairing mitochondrial dynamics due to promotion of mitochondrial biogenesis through activation of the peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α) pathway, inhibiting mitochondrial degradation via decreased autophagy, and facilitating mitochondrial fragmentation involving increased levels of DRP1 and MFN2. The resulting reduced levels of dextran uptake, CD80, CD86 and chemokine receptor 7 (CCR7) suggested that PEG-Fe3 O4 nanoparticles impaired the functionally immature state of DCs. Autophagy inhibitor 3-methyladenine (3-MA) alleviated PEG-Fe3 O4 nanoparticle-induced mitochondrial instability and impairment of the functionally immature state of DCs due to unexpected enhancement of PGC1α/MFN2-mediated coordination of mitochondrial biogenesis and fusion.


Assuntos
Adenina/análogos & derivados , Autofagia/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Nanopartículas Magnéticas de Óxido de Ferro/toxicidade , Mitocôndrias/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Adenina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/metabolismo , Células Dendríticas/patologia , Endocitose/efeitos dos fármacos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Fenótipo
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