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1.
J Org Chem ; 88(23): 16400-16409, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37983977

RESUMO

A mild chlorocyclization of pyrrole-tethered indoles has been realized using POCl3 as the chlorine source and tetramethylene sulfoxide as the promoter. A variety of chlorinated indolizino[8,7-b]indole derivatives have been constructed efficiently under this reaction system in moderate to good yields (19 examples, up to 93% yield).

2.
J Org Chem ; 88(7): 4649-4661, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36947692

RESUMO

We have successfully modified a series of pyrrolo[2,1-a]isoquinolines via direct nitration under mild reaction conditions. Easily accessible nitrates including CAN, Cu(NO3)2·H2O, and Fe(NO3)3·9H2O all can serve as effective nitrating reagents for functionalizing pyrrolo[2,1-a]isoquinolines. Various nitro-bearing pyrrolo[2,1-a]isoquinolines have been efficiently prepared in acceptable to good yields.

3.
Acta Pharmacol Sin ; 44(9): 1801-1814, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37041228

RESUMO

Liver, as an immune and detoxification organ, represents an important line of defense against bacteria and infection and a vulnerable organ that is easily injured during sepsis. Artesunate (ART) is an anti-malaria agent, that also exhibits broad pharmacological activities including anti-inflammatory, immune-regulation and liver protection. In this study, we investigated the cellular responses in liver to sepsis infection and ART hepatic-protective mechanisms against sepsis. Cecal ligation and puncture (CLP)-induced sepsis model was established in mice. The mice were administered ART (10 mg/kg, i.p.) at 4 h, and sacrificed at 12 h after the surgery. Liver samples were collected for preparing single-cell RNA transcriptome sequencing (scRNA-seq). The scRNA-seq analysis revealed that sepsis-induced a dramatic reduction of hepatic endothelial cells, especially the subtypes characterized with proliferation and differentiation. Macrophages were recruited during sepsis and released inflammatory cytokines (Tnf, Il1b, Il6), chemokines (Ccl6, Cd14), and transcription factor (Nfkb1), resulting in liver inflammatory responses. Massive apoptosis of lymphocytes and abnormal recruitment of neutrophils caused immune dysfunction. ART treatment significantly improved the survival of CLP mice within 96 h, and partially relieved or reversed the above-mentioned pathological features, mitigating the impact of sepsis on liver injury, inflammation, and dysfunction. This study provides comprehensive fundamental proof for the liver protective efficacy of ART against sepsis infection, which would potentially contribute to its clinical translation for sepsis therapy. Single cell transcriptome reveals the changes of various hepatocyte subtypes of CLP-induced liver injury and the potential pharmacological effects of artesunate on sepsis.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Sepse , Camundongos , Animais , Artesunato/uso terapêutico , Células Endoteliais/patologia , Sepse/complicações , Sepse/tratamento farmacológico , Análise de Sequência de RNA
4.
Angew Chem Int Ed Engl ; 58(36): 12705-12710, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31297923

RESUMO

Exploring dynamic bonds and their applications in fabricating dynamic materials has received great attention. A photoinduced [2]rotaxane-based dynamic mechanical bond (DMB) features visible-light-triggered dynamic bonding behavior that is essentially distinguished from conventional dynamic chemical bonds. In this DMB, a photoisomerizable ortho-fluoroazobenzene unit is introduced as a steric-controllable stopper, the visible-light-induced dynamic wagging movement of which enables the photoregulated threading of the macrocycle. This allows reversible in situ de-/reforming of the mechanical bond without involving dynamic chemical linkage. The DMB-cross-linked polymeric gel shows interesting photoinduced degradation behavior upon visible light irradiation. Benefiting from the distinctive dual dynamic nature of reversible bonding behavior and mechanical interlocked structure, this DMB is expected to serve as a new type of dynamic bond that can be applied in designing dynamic soft materials.

5.
J Cell Biochem ; 118(11): 4072-4079, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28409883

RESUMO

A previous study has confirmed that the central melanocortin system was able to mediate skeletal muscle AMP-activated protein kinase (AMPK) activation in mice fed a high-fat diet, while activation of the AMPK signaling pathway significantly induced mitochondrial biogenesis. Our hypothesis was that melanocortin 4 receptor (MC4R) was involved in the development of skeletal muscle injury in diabetic rats. In this study, we treated diabetic rats intracerebroventricularly with MC4R agonist R027-3225 or antagonist SHU9119, respectively. Then, we measured the production of reactive oxygen species (ROS), the levels of malondialdehyde (MDA) and glutathione (GSH), the mitochondrial DNA (mtDNA) content and mitochondrial biogenesis, and the protein levels of p-AMPK, AMPK, peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α), sirtuin 1 (SIRT1), and manganese superoxide dismutase (MnSOD) in the skeletal muscle of diabetic rats. The results showed that there was significant skeletal muscle injury in the diabetic rats along with serious oxidative stress and decreased mitochondrial biogenesis. Treatment with R027-3225 reduced oxidative stress and induced mitochondrial biogenesis in skeletal muscle, and also activated the AMPK-SIRT1-PGC-1α signaling pathway. However, diabetic rats injected with MC4R antagonist SHU9119 showed an aggravated oxidative stress and mitochondrial dysfunction in skeletal muscle. In conclusion, our results revealed that MC4R activation was able to attenuate oxidative stress and mitochondrial dysfunction in skeletal muscle induced by diabetes partially through activating the AMPK-SIRT1-PGC-1α signaling pathway. J. Cell. Biochem. 118: 4072-4079, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Receptor Tipo 4 de Melanocortina/metabolismo , Transdução de Sinais , Animais , Diabetes Mellitus Experimental/patologia , Masculino , Mitocôndrias Musculares/patologia , Músculo Esquelético/patologia , Peptídeos/farmacologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ratos , Ratos Sprague-Dawley , Sirtuína 1/metabolismo
6.
J Exp Biol ; 220(Pt 11): 2066-2075, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28566358

RESUMO

Snails of the genus Echinolittorina are among the most heat-tolerant animals; they experience average body temperatures near 41-44°C in summer and withstand temperatures up to at least 55°C. Here, we demonstrate that heat stability of function (indexed by the Michaelis-Menten constant of the cofactor NADH, KMNADH) and structure (indexed by rate of denaturation) of cytosolic malate dehydrogenases (cMDHs) of two congeners (E. malaccana and E. radiata) exceeds values previously found for orthologs of this protein from less thermophilic species. The ortholog of E. malaccana is more heat stable than that of E. radiata, in keeping with the congeners' thermal environments. Only two inter-congener differences in amino acid sequence in these 332 residue proteins were identified. In both cases (positions 48 and 114), a glycine in the E. malaccana ortholog is replaced by a serine in the E. radiata protein. To explore the relationship between structure and function and to characterize how amino acid substitutions alter stability of different regions of the enzyme, we used molecular dynamics simulation methods. These computational methods allow determination of thermal effects on fine-scale movements of protein components, for example, by estimating the root mean square deviation in atom position over time and the root mean square fluctuation for individual residues. The minor changes in amino acid sequence favor temperature-adaptive change in flexibility of regions in and around the active sites. Interspecific differences in effects of temperature on fine-scale protein movements are consistent with the differences in thermal effects on binding and rates of heat denaturation.


Assuntos
Temperatura Corporal , Malato Desidrogenase/química , Caramujos/enzimologia , Adaptação Biológica , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Citosol/enzimologia , Estabilidade Enzimática , Malato Desidrogenase/genética , Malato Desidrogenase/metabolismo , Simulação de Dinâmica Molecular , Desnaturação Proteica , Caramujos/fisiologia
7.
Biol Res ; 50(1): 11, 2017 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28288692

RESUMO

BACKGROUND: Cimicifuga racemosa is one of the herbs used for the treatment of climacteric syndrome, and it has been cited as an alternative therapy to estrogen. Apart from hectic fevers, dyspareunia and so on, dry mouth also increase significantly after menopause. It has not yet been reported whether C. racemosa has any impact on the sublingual gland, which may relate to dry mouth. In an attempt to determine this, we have compared the effects of estrogen and C. racemosa on the sublingual gland of ovariectomized rats. RESULTS: HE staining showed that the acinar cell area had contracted and that the intercellular spaces were broadened in the OVX (ovariectomized rats) group, while treatment with estradiol (E2) and iCR (isopropanolic extract of C. racemosa) improved these lesions. Transmission electron microscopy showed that rough endoplasmic reticulum expansion in mucous and serous acinar epithelial cells and apoptotic cells was more commonly seen in the OVX group than in the SHAM (sham-operated rats) group. Mitochondria and plasma membrane infolding lesions in the striated ducts were also observed. These lesions were alleviated by both treatments. It is of note that, in the OVX + iCR group, the volume of mitochondria in the striated duct was larger than in other groups. Immunohistochemical staining showed that the ratio of caspase-3 positive cells was significantly increased in the acinar cells of the OVX group compared with the SHAM group (p < 0.05); and the MA (mean absorbance) of caspase-3 in the striated ducts also increased (p < 0.05). Estradiol decreased the ratio of caspase-3 positive cells and the MA of caspase-3 in striated ducts significantly (p < 0.05). ICR also reduced the ratio of caspase-3 positive cells and the MA in the striated ducts (p < 0.05), but the reduction of the MA in striated ducts was inferior to that of the OVX + E2 group (p < 0.05). CONCLUSION: Both estradiol and iCR can inhibit subcellular structural damage, and down-regulate the expression of caspase-3 caused by ovariectomy, but their effects were not identical, suggesting that both drugs confer a protective effect on the sublingual gland of ovariectomized rats, but that the specific location and mechanism of action producing these effects were different.


Assuntos
Estradiol/farmacologia , Estrogênios/farmacologia , Ovariectomia , Extratos Vegetais/farmacologia , Glândula Sublingual/efeitos dos fármacos , Células Acinares/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Caspase 3/análise , Caspase 3/efeitos dos fármacos , Climatério/efeitos dos fármacos , Regulação para Baixo , Terapia de Reposição de Estrogênios/métodos , Feminino , Imuno-Histoquímica , Microscopia Eletrônica de Transmissão , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento , Xerostomia/prevenção & controle
8.
Phytomedicine ; 118: 154944, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37393830

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) has become a global health issue owing to its large disease population and high morbidity. We previously reported that the improvement in oxidative stress (OS) using pure total flavonoids from citrus (PTFC), flavonoids isolated from the peel of Citrus changshan-huyou Y.B. Chan, is a crucial strategy for NAFLD treatment. However, OS-associated intervention pathways in NAFLD remain unclear. METHODS: In this study, we used microRNA (miR)- and mRNA-sequencing to identify the pathway by which PTFC improve OS in NAFLD. Clinical data, mimic/inhibitor assays, and a dual-luciferase reporter assay were selected to verify the regulatory relationships of this pathway. Moreover, in vivo and in vitro experiments were used to confime the regulatory effect of PTFC on this pathway. RESULTS: miR-seq, mRNA-seq, and bioinformatics analyses revealed that the miR-137-3p/neutrophil cytosolic factor 2 (NCF2, also known as NOXA2)/cytochrome b-245 beta chain (CYBB, also known as NOX2) pathway may be a target pathway for PTFC to improve OS and NAFLD. Additionally, bivariate logistic regression analysis combining the serum and clinical data of patients revealed NOX2 and NOXA2 as risk factors and total antioxidant capacity (indicator of OS level) as a protective factor for NAFLD. miR-137-3p mimic/inhibitor assays revealed that the upregulation of miR-137-3p is vital for improving cellular steatosis, OS, and inflammation. Dual-luciferase reporter assay confirmed that NOXA2 acts as an miR-137-3p sponge. These results co-determined that miR-137-3p/NOXA2/NOX2 is an essential pathway involved in NAFLD pathogenesis, including lipid accumulation, OS, and inflammation. In vivo and in vitro experiments further confirmed that the miR-137-3p/NOXA2/NOX2 pathway is regulated by PTFC. CONCLUSION: PTFC alleviates OS and inflammation in NAFLD by regulating the miR-137-3p/NOXA2/NOX2 pathway.


Assuntos
Citrus , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Flavonoides/farmacologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Estresse Oxidativo , RNA Mensageiro/metabolismo
9.
Mil Med Res ; 10(1): 7, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36814339

RESUMO

BACKGROUND: Triclosan [5-chloro-2-(2,4-dichlorophenoxy) phenol, TCS], a common antimicrobial additive in many personal care and health care products, is frequently detected in human blood and urine. Therefore, it has been considered an emerging and potentially toxic pollutant in recent years. Long-term exposure to TCS has been suggested to exert endocrine disruption effects, and promote liver fibrogenesis and tumorigenesis. This study was aimed at clarifying the underlying cellular and molecular mechanisms of hepatotoxicity effect of TCS at the initiation stage. METHODS: C57BL/6 mice were exposed to different dosages of TCS for 2 weeks and the organ toxicity was evaluated by various measurements including complete blood count, histological analysis and TCS quantification. Single cell RNA sequencing (scRNA-seq) was then carried out on TCS- or mock-treated mouse livers to delineate the TCS-induced hepatotoxicity. The acquired single-cell transcriptomic data were analyzed from different aspects including differential gene expression, transcription factor (TF) regulatory network, pseudotime trajectory, and cellular communication, to systematically dissect the molecular and cellular events after TCS exposure. To verify the TCS-induced liver fibrosis, the expression levels of key fibrogenic proteins were examined by Western blotting, immunofluorescence, Masson's trichrome and Sirius red staining. In addition, normal hepatocyte cell MIHA and hepatic stellate cell LX-2 were used as in vitro cell models to experimentally validate the effects of TCS by immunological, proteomic and metabolomic technologies. RESULTS: We established a relatively short term TCS exposure murine model and found the TCS mainly accumulated in the liver. The scRNA-seq performed on the livers of the TCS-treated and control group profiled the gene expressions of > 76,000 cells belonging to 13 major cell types. Among these types, hepatocytes and hepatic stellate cells (HSCs) were significantly increased in TCS-treated group. We found that TCS promoted fibrosis-associated proliferation of hepatocytes, in which Gata2 and Mef2c are the key driving TFs. Our data also suggested that TCS induced the proliferation and activation of HSCs, which was experimentally verified in both liver tissue and cell model. In addition, other changes including the dysfunction and capillarization of endothelial cells, an increase of fibrotic characteristics in B plasma cells, and M2 phenotype-skewing of macrophage cells, were also deduced from the scRNA-seq analysis, and these changes are likely to contribute to the progression of liver fibrosis. Lastly, the key differential ligand-receptor pairs involved in cellular communications were identified and we confirmed the role of GAS6_AXL interaction-mediated cellular communication in promoting liver fibrosis. CONCLUSIONS: TCS modulates the cellular activities and fates of several specific cell types (including hepatocytes, HSCs, endothelial cells, B cells, Kupffer cells and liver capsular macrophages) in the liver, and regulates the ligand-receptor interactions between these cells, thereby promoting the proliferation and activation of HSCs, leading to liver fibrosis. Overall, we provide the first comprehensive single-cell atlas of mouse livers in response to TCS and delineate the key cellular and molecular processes involved in TCS-induced hepatotoxicity and fibrosis.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Triclosan , Humanos , Camundongos , Animais , Transcriptoma , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Ligantes , Proteômica , Camundongos Endogâmicos C57BL , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Fibrose , Doença Hepática Induzida por Substâncias e Drogas/patologia
10.
ACS Appl Mater Interfaces ; 15(3): 3744-3759, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36630299

RESUMO

Inducing immunogenic cell death (ICD) is a critical strategy for enhancing cancer immunotherapy. However, inefficient and risky ICD inducers along with a tumor hypoxia microenvironment seriously limit the immunotherapy efficacy. Non-specific delivery is also responsible for this inefficiency. In this work, we report a drug-free bacteria-derived outer membrane vesicle (OMV)-functionalized Fe3O4-MnO2 (FMO) nanoplatform that realized neutrophil-mediated targeted delivery and photothermally enhanced cancer immunotherapy. In this system, modification of OMVs derived from Escherichia coli enhanced the accumulation of FMO NPs at the tumor tissue through neutrophil-mediated targeted delivery. The FMO NPs underwent reactive decomposition in the tumor site, generating manganese and iron ions that induced ICD and O2 that regulated the tumor hypoxia environment. Moreover, OMVs are rich in pathogen-associated pattern molecules that can overcome the tumor immunosuppressive microenvironment and effectively activate immune cells, thereby enhancing specific immune responses. Photothermal therapy (PTT) caused by MnO2 and Fe3O4 can not only indirectly stimulate systemic immunity by directly destroying tumor cells but also promote the enrichment of neutrophil-equipped nanoparticles by enhancing the inflammatory response at the tumor site. Finally, the proposed multi-modal treatment system with targeted delivery capability realized effective tumor immunotherapy to prevent tumor growth and recurrence.


Assuntos
Bioengenharia , Imunoterapia , Nanopartículas Multifuncionais , Neoplasias , Humanos , Linhagem Celular Tumoral , Imunoterapia/métodos , Nanopartículas Multifuncionais/uso terapêutico , Neoplasias/terapia , Microambiente Tumoral/imunologia , Vesículas Transportadoras/química , Vesículas Transportadoras/imunologia , Membrana Externa Bacteriana/química , Membrana Externa Bacteriana/imunologia , Escherichia coli
11.
Front Surg ; 9: 1009119, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406377

RESUMO

Background: Choriocarcinoma is a malignant tumour of trophoblastic origin. Most are gestational choriocarcinomas, which usually occur in women with an epithelial origin of the placental chorionic villi and are associated with pregnancy. It mainly originates in the gonads such as the ovaries and testes. However, it rarely occurs in the stomach and is known as primary choriocarcinoma (PGC). Case presentation: A 69-year-old man complained of abdominal distention for 3 years, which worsened 1 week later. Gastroscopy showed chronic atrophic gastritis C1 (C1: indicates atrophic gastritis involving the sinus region); the pathology report of the gastroscopic specimen showed high-grade epithelial tumours in the mucosal glands. We diagnosed an occupying lesion in the stomach and performed a laparoscopically assisted distal gastrectomy and Billroth type 1 anastomosis. Postoperative pathology showed "gastric choriocarcinoma with cancerous tissue invading the entire gastric wall". The patient was discharged on the 11th postoperative day as there were no postoperative complications. The patient was followed up until June 2022 with a good recovery and no recurrence. Conclusion: We encountered a case of Primary Gastric Choriocarcinoma, where the cancerous tissue invades the full thickness of the gastric wall.

12.
Bio Protoc ; 12(1): e4282, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35118174

RESUMO

Many of the current methods for enzyme purification and immobilization suffer from several drawbacks, such as requiring tedious multistep procedures or long preparation, and being environmentally unfriendly, due to the chemicals and conditions involved. Thus, a simple technique for direct purification and immobilization of target enzymes from cell lysates was proposed. The elastin-like polypeptides (ELPs)-SpyCatcher chimera could mediate the formation of silica carriers within seconds and the target enzymes were then covalently immobilized on silica carriers via SpyCatcher/SpyTag spontaneous reaction. These tailor-made carriers were easily prepared, with precisely controlled morphology and size, as well as none-consuming surface modification needed, which could specifically immobilize the SpyTag-fused target enzymes from the cell lysate without pre-purification.

13.
Integr Cancer Ther ; 20: 15347354211031650, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34261372

RESUMO

BACKGROUND: Traditional Chinese medicine (TCM) is widely integrated into cancer care in China. An overview in 2011 identified 2384 randomized and non-randomized controlled trials (RCTs, non-RCTs) on TCM for cancer published in the Chinese literature. This article summarizes updated evidence of RCTs on TCM for cancer care. METHODS: We searched 4 main Chinese databases: China National Knowledge Infrastructure, Chinese Scientific Journal Database, SinoMed, and Wanfang. RCTs on TCM used in cancer care were analyzed in this bibliometric study. RESULTS: Of 5834 RCTs (477 157 cancer patients), only 62 RCTs were indexed in MEDLINE. The top 3 cancers treated were lung, stomach, and breast cancer. About 4752 RCTs (81.45%) tested TCM combined with conventional treatment, and 1082 RCTs (18.55%) used TCM alone for treating symptoms and side-effects. Herbal medicine was the most frequently used TCM modality (5087 RCTs; 87.20%). The most frequently reported outcome was symptom improvement (3712 RCTs; 63.63%) followed by quality of life (2725 RCTs; 46.71%), and biomarkers (2384 RCTs; 40.86%). The majority of RCTs (4051; 69.44%) concluded there were beneficial effects using either TCM alone or TCM plus conventional treatment compared with conventional treatment. CONCLUSION: Substantial randomized trials demonstrated different types/stages of cancer were treated by various TCM modalities, alone or in combination with conventional medicine. Further evaluation on the effects and safety of TCM modalities focusing on outcomes such as quality of life is required.


Assuntos
Neoplasias da Mama , Medicamentos de Ervas Chinesas , China , Medicamentos de Ervas Chinesas/uso terapêutico , Feminino , Humanos , Medicina Tradicional Chinesa , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Inorg Chem ; 49(21): 9731-3, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20919694

RESUMO

Tn clusters are usually connected into frameworks by sulfur bridges. A new type of T4 compounds in which the clusters are linked by both sulfur bridges and transition metal complexes are described.

15.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 76(Pt 6): 1001-1017, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33289712

RESUMO

Seven new metal-organic frameworks (MOFs), namely, [Zn2(L1)(H2O)3]n (1), [Zn2(L1)(dib)(H2O)2]n (2), {[Zn2(L1)(4,4'-bipy)(H2O)2]·H2O}n (3), [Cd2(L1)(1,10-phen)]n (4), [Ni2(HL1)(4,4'-bipy)(µ3-OH)(µ2-H2O)]n (5), {[Co4(L1)(4,4'-bibp)3]·(4,4'-bibp)3}n (6), and [Co2(L2)(4,4'-bibp)2(H2O)]n (7), where H4L1 and H4L2 are semi-rigid 3-(3,5-dicarboxylphenoxy)phthalic acid and 4-(3,5-dicarboxylphenoxy)phthalic acid, respectively, and 4,4'-bipy is 4,4'-bipyridine, dib is 1,4-bis(1H-imidazol-1-yl)benzene, 1,10-phen is 1,10-phenanthroline and 4,4'-bipb is 1,4-bis(pyridin-4-yl)benzene, have been prepared under solvothermal conditions with ZnII, CdII, CoII and NiII ions in the presence of auxiliary N-donor ligands. The crystal structures and photoluminescence and magnetic properties of these compounds have been investigated. Compound 1 displays a 3,4,6-connected two-dimensional (2D) topology with a Schläfli symbol of (42.5)2(43.52.7)(45.56.63)2, and the 2D structure was further assembled to form a three-dimensional (3D) framework by intermolecular O-H...O hydrogen bonds. Compound 2 features a novel 3,3,4-connected structure and the point symbol is (4.102)(4.6.84)(62.8). Compound 3 exhibits a 3,4,6-connected 3-nodal net having a 3,4,6 T53 type topology, with the point symbol (4.62)2(42.64)2(42.68.82.103). Compound 4 shows a 2D→3D supramolecular structure formed by π-π stacking interactions. Compound 5 possesses a 3D framework with a tfz-d net topology. Compounds 6 and 7 are constructed from the same auxiliary ligand and metal salt at the same temperature, but with different main ligands and exhibiting different topologies. Compound 6 presents a 3D 4,6-connected topological network with a Schläfli symbol of (3.44.6)(32.44.56.63), while compound 7 has a 3D topological network with a Schläfli symbol of (412.616). Magnetic analyses indicate that compounds 5 and 7 show weak antiferromagnetic interactions.

16.
Chem Commun (Camb) ; 53(39): 5396-5399, 2017 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-28451683

RESUMO

Linear tetrathiafulvalene (TTF) oligomers were synthesized, which could not only form a pleated TTF˙+ radical cation foldamer under oxidation conditions, but also interlocked with CBPQT4+ to form folded donor-acceptor [3]pseudorotaxane in the neutral state of TTF. Moreover, switchable transformation between these two folded supramolecular structures was achieved under the alternative regulation of the redox states of TTF units.

17.
Chem Commun (Camb) ; 52(98): 14085-14088, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27840880

RESUMO

Light-triggered photoisomerization of the azobenzene (AB) unit in bistable [2]rotaxanes can cause the shuttling of the macrocycle on the dumbbell, resulting in distinctive dual spectral variation characteristics: (1) the spectral change of the photochromic unit and (2) the variation of the charge-transfer band. By employing the CT bond region as an output signal, non-destructive readout of optical information could be achieved.


Assuntos
Luz , Rotaxanos/química , Compostos Azo/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrofotometria Ultravioleta
18.
Biol. Res ; 50: 11, 2017. graf
Artigo em Inglês | LILACS | ID: biblio-838967

RESUMO

BACKGROUND: Cimicifuga racemosa is one of the herbs used for the treatment of climacteric syndrome, and it has been cited as an alternative therapy to estrogen. Apart from hectic fevers, dyspareunia and so on, dry mouth also increase significantly after menopause. It has not yet been reported whether C. racemosa has any impact on the sublingual gland, which may relate to dry mouth. In an attempt to determine this, we have compared the effects of estrogen and C. racemosa on the sublingual gland of ovariectomized rats. RESULTS: HE staining showed that the acinar cell area had contracted and that the intercellular spaces were broadened in the OVX (ovariectomized rats) group, while treatment with estradiol (E2) and iCR (isopropanolic extract of C. racemosa) improved these lesions. Transmission electron microscopy showed that rough endoplasmic reticulum expansion in mucous and serous acinar epithelial cells and apoptotic cells was more commonly seen in the OVX group than in the SHAM (sham-operated rats) group. Mitochondria and plasma membrane infolding lesions in the striated ducts were also observed. These lesions were alleviated by both treatments. It is of note that, in the OVX + iCR group, the volume of mitochondria in the striated duct was larger than in other groups. Immunohistochemical staining showed that the ratio of caspase-3 positive cells was significantly increased in the acinar cells of the OVX group compared with the SHAM group (p < 0.05); and the MA (mean absorbance) of caspase-3 in the striated ducts also increased (p < 0.05). Estradiol decreased the ratio of caspase-3 positive cells and the MA of caspase-3 in striated ducts significantly (p < 0.05). ICR also reduced the ratio of caspase-3 positive cells and the MA in the striated ducts (p < 0.05), but the reduction of the MA in striated ducts was inferior to that of the OVX + E2 group (p < 0.05). CONCLUSION: Both estradiol and iCR can inhibit subcellular structural damage, and down-regulate the expression of caspase-3 caused by ovariectomy, but their effects were not identical, suggesting that both drugs confer a protective effect on the sublingual gland of ovariectomized rats, but that the specific location and mechanism of action producing these effects were different.


Assuntos
Animais , Feminino , Ratos , Glândula Sublingual/efeitos dos fármacos , Extratos Vegetais/farmacologia , Ovariectomia , Estradiol/farmacologia , Estrogênios/farmacologia , Fatores de Tempo , Xerostomia/prevenção & controle , Climatério/efeitos dos fármacos , Imuno-Histoquímica , Regulação para Baixo , Terapia de Reposição de Estrogênios/métodos , Reprodutibilidade dos Testes , Resultado do Tratamento , Ratos Sprague-Dawley , Apoptose/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Caspase 3/análise , Caspase 3/efeitos dos fármacos , Células Acinares/efeitos dos fármacos
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