RESUMO
Burkitt's lymphoma (BL) has a particularly extremely poor prognosis and the fastest growth rate among human tumors, and the development of new drugs for the treatment of BL is urgently needed. In this study, the cytotoxic properties of 3,7-bis(3,5-dimethylphenyl)-aaptamine (AP-51), a new semisynthetic alkaloid derived from the marine natural product aapatamine, were investigated using BL cell lines. Our results showed that AP-51 inhibited the proliferation of Daudi and Raji cells with IC50 values of 3.48 and 2.07 µM, respectively. Flow cytometry and Western blot analyses showed that AP-51 initiated G0/G1 phase arrest by modulating the expression of cyclin-dependent kinases (CDKs). AP-51 also induced apoptosis, as demonstrated by nuclear fragmentation, downregulation of BCL-XL and Mcl-1, and upregulation of cleaved caspase-9, cleaved caspase-3, cleaved-PARP, and cytochrome c, the markers of apoptosis regulated via the mitochondrial pathway. When it comes to mitochondria, AP-51 treatment also significantly increased the levels of intracellular mitochondrial superoxide, decreased ATP content, and reduced the expression of ATP synthase, as well as the expression of the mitochondrial respiratory chain complexes. Finally, AP-51 treatment significantly inhibited the PI3K/AKT/mTOR signaling pathway, which was shown to be associated with the induction of apoptosis. Collectively, these findings indicated that AP-51 initiated cell cycle arrest, induced apoptosis, caused mitochondrial dysfunction, and decreased the phosphorylation of PI3K/AKT/mTOR signaling pathway-related proteins and the protein levels of C-MYC, suggesting that AP-51 has therapeutic potential as a possible treatment for Burkitt's lymphoma.
Assuntos
Alcaloides , Antineoplásicos , Linfoma de Burkitt , Poríferos , Animais , Humanos , Trifosfato de Adenosina , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Linhagem Celular Tumoral , Proliferação de Células , Mitocôndrias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Poríferos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismoRESUMO
BACKGROUND: Atopy may be associated with disease severity and a poor prognosis of human adenovirus (HAdV) pneumonia in children. Our aim was to observe the clinical characteristics and pulmonary radiological changes in children with atopy and HAdV pneumonia in China. METHODS: Children hospitalised with HAdV pneumonia from June 2018 to December 2019 were analysed. All children were divided into atopic with HAdV, non-atopic with HAdV, and atopic without HAdV infection group. Each group was further divided into the mild and severe pneumonia groups according to disease severity. Standard treatment was initiated after admission, and regular follow-up evaluations were conducted at 1 month after discharge. Baseline and clinical characteristics and pulmonary radiological changes in children with and without atopy were evaluated. Risk factors associated with small airway lesions in patients with HAdV pneumonia were analysed. RESULTS: The eosinophil count in the atopic group was significantly higher than that in the non-atopic group (P < 0.05). Severe coughing, wheezing, and small airway lesions on chest high-resolution computed tomography (HRCT) upon admission, after discharge and 1 month after discharge were significantly higher in the atopic group (with or without HAdV infection) than in the non-atopic group (P < 0.05). There were significant differences in the number of patients with wheezing and small airway lesions during hospitalisation and after discharge among the three groups (P < 0.05). The risks of small airway lesions in children with a family or personal history of asthma, severe infection, atopy, and HAdV infection were 2.1-, 2.7-, 1.9-, 2.1-, and 1.4-times higher than those in children without these characteristics, respectively. CONCLUSIONS: Children with atopy and HAdV pneumonia may experience severe coughing in mild cases and wheezing in mild and severe cases. Children with atopy are more susceptible to the development of small airway lesions, recurrent wheezing after discharge and slower recovery of small airway lesions as observed on pulmonary imaging than non-atopic children after HAdV infection. A family or personal history of asthma, atopy, severe infection, and HAdV infection are independent risk factors associated with the development of small airway lesion as observed on chest HRCT.
Assuntos
Infecções por Adenoviridae , Infecções por Adenovirus Humanos , Adenovírus Humanos , Pneumonia Viral , Infecções por Adenovirus Humanos/complicações , Infecções por Adenovirus Humanos/epidemiologia , Criança , Humanos , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/epidemiologia , PrognósticoRESUMO
Dysiscalarones A-E (1-5), five new scalarane-type bishomoscalarane sesterterpenoids, were isolated from marine sponge Dysidea granulosa collected from the South China Sea, together with two known ones, honulactone A (6) and phyllofolactone I (7). The new structures were determined by extensive spectroscopic analysis including HR-ESI-MS and 1D and 2D NMR data, and their absolute configurations were assigned by single crystal X-ray diffraction analyses. The inhibitory activity of all the seven isolates on the production of nitric oxide (NO) stimulated by lipopolysaccharide (LPS) in mouse RAW 264.7 macrophages was evaluated. Of these metabolites, dysiscalarones A-B (1-2), honulactone A (6), and phyllofolactone I (7) showed inhibitory activities with respective IC50 values of 16.4, 18.5, 2.6, and 3.7 µM, which suggested that the γ-methylated α,ß-unsaturated γ-lactone might be the functional group. In addition, all the seven metabolites showed no significant cytotoxicity against lung cancer PC9 cell line at the concentration of 20 µM.
Assuntos
Dysidea/química , Óxido Nítrico/antagonistas & inibidores , Sesterterpenos/farmacologia , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Células RAW 264.7 , Sesterterpenos/química , Sesterterpenos/isolamento & purificação , Relação Estrutura-AtividadeRESUMO
Eleven new nitrogenous meroterpenoids, cinerols A-K (1-11), were isolated from the marine sponge Dysidea cinerea collected in the South China Sea, and their structures were determined by detailed spectroscopic analysis. Cinerols A (1) and B (2) feature a rare 5H-pyrrolo[1,2a]benzimidazole moiety, while cinerols C-G (3-7) are examples of rare meroterpene benzoxazoles. The cinerols are noncytotoxic to human melanoma A375 cells at the concentration of 32 µM; however, selected cinerols exhibit moderate inhibitory activity against one or more of protein-tyrosine phosphatase 1B, ATP-citrate lyase, and SH2 domain-containing phosphatase-1 with IC50 values of 2.8-27 µM.
Assuntos
Monoterpenos/isolamento & purificação , Nitrogênio/química , Poríferos/química , Animais , Biologia Marinha , Monoterpenos/química , Monoterpenos/farmacologiaRESUMO
Four new cycloheptapeptides, fuscasins A-D (1-4), were isolated from the marine sponge Phakellia fusca collected from the South China Sea. Their planar structures were fully characterized by spectroscopic methods, and the absolute configurations of amino acid residues were determined using the advanced Marfey's method. Structurally, 1 is a unique cycloheptapeptide with a backbone bearing a pyrrolidine-2,5-dione unit. Among the isolated compounds, 1 exhibited potent growth-inhibitory activity against HepG2 cells with an IC50 value of 4.6 µM, whereas it did not show apparent inhibitory effects against the other five human cancer cell lines, MCF-7, HeLa, NCI-H460, PC9, and SW480. Encouragingly, 1 exhibited no cytotoxicity against nonmalignant cells even with a concentration up to 100 µM. These findings suggest that 1 may display a selective inhibitory effect on the growth of HepG2 cells.
Assuntos
Peptídeos Cíclicos/isolamento & purificação , Poríferos/química , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Biologia MarinhaRESUMO
Asthma is a heterogeneous clinical syndrome characterized by airway inflammation, hyper-responsiveness and remodeling. Airway remodeling is irreversible by current antiasthmatic drugs, and it is the main cause of severe asthma. Airway smooth muscle cells (ASMCs) act as the main effector cells for airway remodeling; the proliferation and hypertrophy of which are involved in airway remodeling. Caveolin (Cav)-â¯1 is present on the surface of ASMCs, which is involved in cell cycle and signal transduction regulation, allowing ASMCs to change from proliferation to apoptosis. The extracellular signal-regulated kinase (ERK)1/2 signaling pathway is a common pathway regulated by various proliferative factors, which demonstrates a regulatory role in airway remodeling of asthma. There have been many studies on the correlation between vasoactive intestinal peptide (VIP) and airway reactivity and inflammation in asthma, but the functions and related mechanisms of ASMCs remain unclear. In this study, we established an airway remodeling model in asthmatic mice, and concluded that VIP inhibits airway remodeling in vivo. The in vitro effect of VIP on interleukin-13-induced proliferation of ASMCs was studied by examining the effects of VIP on expression of ERK1/2, phospho-ERK1/2 and Cav-1 in ASMCs, as well as changes in cell cycle distribution. VIP inhibited phosphorylation of the ERK1/2 signaling pathway and expression of Cav-1 on ASMCs and decreased the proportion of S phase cells in the cell cycle, thus inhibiting the proliferation of ASMCs. This study provides a novel therapeutic mechanism for the treatment of asthma.
Assuntos
Asma/tratamento farmacológico , Modelos Animais de Doenças , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Miócitos de Músculo Liso/efeitos dos fármacos , Peptídeo Intestinal Vasoativo/farmacologia , Remodelação das Vias Aéreas/efeitos dos fármacos , Animais , Asma/metabolismo , Asma/patologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismoRESUMO
OBJECTIVE: To observe the curative effect of porous tantalum rod and Gugutou Huaisiyu Capsule (GHC) for steroid-induced osteonecrosis of femoral head (SONFH). METHODS: A total 60 hips of 50 SONFH patients were randomly assigned to the treatment group and the control group according to grouping time, 25 in each group (30 hips). Patients in the control group were implanted with porous tantalum rod, while those in the treatment group additionally took GHC (5 pills each time, three time per day for 2 successive months; and then twice per day for 4 successive months). Then all patients were followed-up to observe Harris hip score. The curative effect and the femoral head survival time were assessed. RESULTS: A total of 49 patients (59 hips) were followed-up. The Harris hip score of the two groups at the final follow-up was significantly improved after treatment, with statistical difference when compared with before treatment (P < 0.01). Besides, it was higher in the treatment group than in the control group. The curative effect and the survival time were superior in the treatment group, with statistical difference when compared with the control group (P < 0.05). CONCLUSIONS: Porous tantalum rod combined GHC got better effect in treating SONFH. It could significantly improve the function of affected hips and prolong the survival time of femoral head.
Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Necrose da Cabeça do Fêmur/tratamento farmacológico , Tantálio , Cápsulas , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Próteses e Implantes , Esteroides/efeitos adversosRESUMO
Diffuse large B-cell lymphoma (DLBCL) is a genetically heterogeneous non-Hodgkin lymphoma that is extremely aggressive and has an intermediate to high malignancy. Some patients still experience treatment failure, relapse, or resistance to rituximab, cyclophosphamide, adriamycin, vincristine, and prednisone (R-CHOP) therapy. Therefore, there is an urgent need for further research on new agents for the treatment of DLBCL. AP-48 is an aaptamine alkaloid analog with potent anti-tumor effects that originates from marine natural products. In this study, we found that AP-48 exhibits dose-dependent cytotoxicity in DLBCL cell lines. Flow cytometry showed that AP-48 induced cell cycle arrest in the G0/G1 phase in SU-DHL-4 and Farage cells and in the S phase in WSU-DLCL-2 cells. AP-48 also accelerated apoptosis via the caspase-3-mediated intrinsic apoptotic pathway. Further experiments demonstrated that AP-48 exerted its anti-DLBCL effects through the PI3K/AKT/mTOR pathway, and that the PI3K agonist YS49 partially alleviated the inhibition of cell proliferation and apoptosis induced by AP-48. Finally, in a tumor xenograft model, AP-48 inhibited tumor growth and promoted apoptosis in tumor tissues, indicating its therapeutic potential in DLBCL.
Assuntos
Alcaloides , Apoptose , Linfoma Difuso de Grandes Células B , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Serina-Treonina Quinases TOR , Ensaios Antitumorais Modelo de Xenoenxerto , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/metabolismo , Humanos , Serina-Treonina Quinases TOR/metabolismo , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Alcaloides/farmacologia , Linhagem Celular Tumoral , Camundongos , Apoptose/efeitos dos fármacos , Poríferos/química , Camundongos Nus , Proliferação de Células/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Antineoplásicos/farmacologiaRESUMO
PURPOSE: Acute erythroleukemia (AEL) is a rare and highly aggressive subtype of acute myeloid leukemia (AML) with an extremely poor prognosis when treated with available drugs. Therefore, new investigational agents capable of inducing remission are urgently required. METHODS: Bioinformatics analysis, western blot and qRT-PCR were used to reveal the potential biological mechanism of bryostatin 4 (B4), an antineoplastic macrolide derived from the marine bryozoan Bugula neritina. Then, in vivo experiments were conducted to evaluate the role of transforming growth factor (TGF)-ß signaling in the progression of AEL. RESULTS: Our results revealed that the proliferation of K562 cells and TF-1 cells was significantly inhibited by B4 at IC50 values of 37 nM and 52 nM, respectively. B4 inhibited TGF-ß signaling and its downstream pathway targets, particularly the phosphorylation of Smad2, Smad3, Ras, C-RAF, ERK1/2, and MEK. B4 also played an important role in cell invasion and migration in K562 cells and TF-1 cells by reducing the protein levels of the mesenchymal cell marker vimentin. Moreover, Flow cytometry and western blot analyses demonstrated that B4 induced apoptosis and initiated G0/G1 phase arrest by modulating mitochondrial dysfunction and cyclin-dependent kinase (CDK) expression. CONCLUSION: These findings indicated that B4 could inhibit the proliferation, migration, invasion, and TGF-ß signaling pathways of AEL cells, thus suggesting that B4 possesses therapeutic potential as a treatment for AEL.
RESUMO
Multidrug resistance is a substantial obstacle in treating non-small cell lung cancer (NSCLC) with therapies like cisplatin (DDP)-based adjuvant chemotherapy and EGFR-tyrosine kinase inhibitors (TKIs). Aaptamine-7 (AP-7), a benzonaphthyridine alkaloid extracted from Aaptos aaptos sponge, has been shown to exhibit a broad spectrum of anti-tumor activity. However, the anti-cancer activity of AP-7 in combination with DDP and its molecular mechanisms in multidrug-resistant NSCLC are not yet clear. Our research indicates that AP-7 bolsters the growth inhibition activity of DDP on multidrug-resistant NSCLC cells. AP-7 notably disrupts DDP-induced cell cycle arrest and amplifies DDP-induced DNA damage effects in these cells. Furthermore, the combination of AP-7 and DDP downregulates Chk1 activation, interrupts the DNA damage repair-dependent Chk1/CDK1 pathway, and helps to overcome drug resistance and boost apoptosis in multidrug-resistant NSCLC cells and a gefitinib-resistant xenograft mice model. In summary, AP-7 appears to enhance DDP-induced DNA damage by impeding the Chk1 signaling pathway in multidrug-resistant NSCLC, thereby augmenting growth inhibition, both in vitro and in vivo. These results indicate the potential use of AP-7 as a DDP sensitizer in the treatment of multidrug-resistant NSCLC.
RESUMO
Marine sponges are well known as prolific producers of structurally diverse molecules with valuable pharmacological potential. As part of our ongoing program to discover bioactive compounds from marine sponges collected from the Xisha Islands in the South China Sea, a chemical study on the specimens of Hippospongia lachne was conducted. As a result, eight undescribed compounds, including four zwitterionic alkylpyridinium salts, hippospondines A-D (1-4), and four 3-alkylpyridine alkaloids, hippospondines E (5), F (6), and (±)-hippospondine G (7), were isolated from the marine sponge H. lachne, together with one known 3-alkylpyridine alkaloid (8). The undescribed structures were elucidated by HRESIMS, NMR, DP4+ and CP3 probability analysis, and the Snatzke's method. Hippospondines A-D (1-4) represent the rare example of inner salt type alkylpyridinium alkaloid with a farnesyl moiety. Compounds 1-3 and 8 were subjected to cytotoxic and lymphocyte proliferation assays. Compound 3 exhibited a weak promotion effect on the ConA-induced T lymphocyte proliferation.
Assuntos
Alcaloides , Antineoplásicos , Poríferos , Animais , Espectroscopia de Ressonância Magnética , Antineoplásicos/química , Alcaloides/química , China , Estrutura MolecularRESUMO
Objective: The purpose of this study was to investigate the bacterial communities of biting midges and ticks collected from three sites in the Poyang Lake area, namely, Qunlu Practice Base, Peach Blossom Garden, and Huangtong Animal Husbandry, and whether vectors carry any bacterial pathogens that may cause diseases to humans, to provide scientific basis for prospective pathogen discovery and disease prevention and control. Methods: Using a metataxonomics approach in concert with full-length 16S rRNA gene sequencing and operational phylogenetic unit (OPU) analysis, we characterized the species-level microbial community structure of two important vector species, biting midges and ticks, including 33 arthropod samples comprising 3,885 individuals, collected around Poyang Lake. Results: A total of 662 OPUs were classified in biting midges, including 195 known species and 373 potentially new species, and 618 OPUs were classified in ticks, including 217 known species and 326 potentially new species. Surprisingly, OPUs with potentially pathogenicity were detected in both arthropod vectors, with 66 known species of biting midges reported to carry potential pathogens, including Asaia lannensis and Rickettsia bellii, compared to 50 in ticks, such as Acinetobacter lwoffii and Staphylococcus sciuri. We found that Proteobacteria was the most dominant group in both midges and ticks. Furthermore, the outcomes demonstrated that the microbiota of midges and ticks tend to be governed by a few highly abundant bacteria. Pantoea sp7 was predominant in biting midges, while Coxiella sp1 was enriched in ticks. Meanwhile, Coxiella spp., which may be essential for the survival of Haemaphysalis longicornis Neumann, were detected in all tick samples. The identification of dominant species and pathogens of biting midges and ticks in this study serves to broaden our knowledge associated to microbes of arthropod vectors. Conclusion: Biting midges and ticks carry large numbers of known and potentially novel bacteria, and carry a wide range of potentially pathogenic bacteria, which may pose a risk of infection to humans and animals. The microbial communities of midges and ticks tend to be dominated by a few highly abundant bacteria.
Assuntos
Ceratopogonidae , Microbiota , Carrapatos , Animais , Humanos , Carrapatos/microbiologia , Ceratopogonidae/genética , Filogenia , RNA Ribossômico 16S/genética , Estudos Prospectivos , Coxiella/genéticaRESUMO
Two new 9,11-secosterols, hipposponols A (1) and B (2), together with five known analogues, aplidiasterol B (3), (3ß,5α,6ß)-3,5,6-triol-cholest-7-ene (4), (3ß,5α,6ß,22E)-3,5,6-triol-ergosta-7,22-diene (5), and one pair of inseparable C-24 epimers of (3ß,5α,6ß,22E)-3,5,6-triol-stigmasta-7,22-diene (6/7), were isolated from the marine sponge Hippospongia lachne de Laubenfels. The structures of isolated compounds were extensively elucidated based on HRESIMS and NMR data. Compounds 2 - 5 showed cytotoxicity against PC9 cells with IC50 values ranging from 34.1 ± 0.9 to 38.9 ± 1.0 µM and compound 4 displayed cytotoxicity against MCF-7 cells with IC50 value of 39.0 ± 0.4 µM.
RESUMO
The precursor ion scanning-supercritical fluid chromatography (PI-SFC) method was applied to explore new methionine sulfoxide-containing cycloheptapeptides, axinellasins A-D (1-4), from the marine sponge Axinella sp. Their structures, including absolute configurations, were elucidated by detailed spectroscopic analyses and X-ray crystallography. The total synthesis of 4 was completed via an Fmoc solid/solution-phase synthesis. Compounds 1-4 exhibited immunosuppressive effects via inhibition of T and B cell proliferation, and 1 and 4 showed better inhibitory activities than their corresponding diastereomers.
Assuntos
Axinella , AnimaisRESUMO
Myxoid adrenal cortical adenoma with a pseudoglandular structure is a special histological variant and is extremely rare. We report about a 32-year-old Chinese woman with a right adrenal mass during a routine physical examination. The cut surface of the mass had a vague nodular, which gross appearance was pale, yellowish, and semitransparent. Histologically, the region is mostly characterised by pseudoglandular pattern with myxoid stroma. They are filled with clear cells or eosinophilic cells, as well as semitransparent regions, in which anastomosing small eosinophilic cells arranged in pseudoglandular, cord-like, or wreath-shaped structure float in the mucous pool. Immunohistochemical staining shows Melan-A, vimentin, and CD56 were positive and CK (AE1/AE3) were nucleus-side staining. A small number of tumor cells were positive for alpha-inhibin and synaptophysin, ki-67 labeling index was 3%. EMA, chromogranin A, WT-1, and P63 were negative. This report aimed to emphasize pseudoglandular patterns with mucus secretion which could occur in adenomas of the adrenal cortex, nucleus-side positive for CK is remarkable. However, this type may have malignant potential, so regular follow-up is needed.
RESUMO
A neutral-loss scanning mass method was used to explore new kynurenine-containing cycloheptapeptides, phakefustatins A-C (1-3), from the marine sponge Phakellia fusca. Their structures were elucidated by spectroscopic analysis and the advanced Marfey's method. 1 was total synthesized via a final-stage ozonolysis strategy by the combination of solid/solution-phase synthesis. Phakefustatin A (1) was identified as a RXRα modulator to inhibit cancer cell growth, and its pharmacophores could be Kyn and guanidine groups.
Assuntos
Cinurenina/química , Peptídeos Cíclicos/química , Poríferos/química , Animais , Estrutura Molecular , Análise EspectralRESUMO
OBJECTIVE: This study evaluated the clinical value of drug-coated balloons for patients with small-vessel coronary artery disease (SVD). METHODS: A computerized literature search was performed using the databases to conduct a meta-analysis and evaluate the clinical value of drug-coated balloons among patients with SVD. RESULTS: This review enrolling 1545 patients receiving drug-coated balloons and 1010 patients receiving stents (including drug-eluting stents and bare-metal stents). The meta-analysis results showed that the incidence of major adverse cardiovascular events among patients with SVD did not significantly differ between the drug-coated balloon group and the stent group within 1 postoperative year (odds ratioâ=â0.81, Pâ=â.5). A subgroup analysis showed that the incidence of myocardial infarction among the drug-coated balloon group was significantly lower than that among the stent group (odds ratioâ=â0.58, Pâ=â.04). Nevertheless, the late lumen loss of the drug-coated balloon group was significantly lower than that of the stent group (mean differenceâ=â0.31, Pâ=â.01). CONCLUSIONS: Drug-coated balloons can be used to effectively reduce the incidence of myocardial infarction in patients with SVD within 1 year and decrease the extent of late lumen loss without increasing the incidence of major adverse cardiovascular events.
Assuntos
Angioplastia Coronária com Balão/efeitos adversos , Doença da Artéria Coronariana/cirurgia , Stents Farmacológicos/efeitos adversos , Infarto do Miocárdio/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Fármacos Cardiovasculares/administração & dosagem , Estudos de Casos e Controles , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Vasos Coronários/cirurgia , Feminino , Humanos , Incidência , Masculino , Infarto do Miocárdio/etiologia , Razão de Chances , Complicações Pós-Operatórias/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Stents Metálicos Autoexpansíveis/efeitos adversos , Resultado do TratamentoRESUMO
Existing distortion functions in steganography which achieved high undetectability are designed for unprocessed natural image. Nowadays, a large number of images are filtered before transmitting for the sake of beautification. In this situation, existing distortion functions should be improved to fit the properties of these beautified images. This paper proposes a distortion function optimization method for steganography on beautified images. Given an unprocessed image, a popular image beautification software is employed to produce two similar beautified images. One of them is used for embedding and the other one is employed as reference. Guided by the reference, existing distortion functions are improved by distinguishing the embedding costs for ±1 embedding. After embedding, the stego image is closer to the reference, which results in a higher undetectability against steganalysis. Experimental results also proved the increasing of undetectability when examined by modern steganalytic tools.
Assuntos
Segurança Computacional , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/métodos , Informática/métodos , Algoritmos , Estética , Reprodutibilidade dos Testes , SoftwareRESUMO
To investigate the involvement of blood-born factors and extracellular proteases in axonal degeneration and regeneration in both PNS and CNS, we directly compared the differences of blood-nerve barrier (BNB) disruption and matrix metalloprotease-9 (MMP-9) induction between the sciatic nerve and optic nerve after crush injury in the same animal. In sciatic nerve, BNB disruption, fibrin(ogen) deposition and MMP-9 expression were observed only in the first week following injury. Neurofilament (NF) immunoreactivity dramatically decreased in the first 2 days, gradually recovered to the normal levels by day 28. In contrast, the immunoglobulin G deposits spanned from 4 h to 28 days in crushed optic nerves. Fibrin(ogen) deposition was only observed in the first 2 days, while MMP-9 induction did not occur until a week after injury but lasted for 3 weeks in the crushed optic nerves. The NF immunoreactivity did not change much until day 7 and almost completely disappeared on day 28. The decrease of NF immunoreactivity coincided with the induction of MMP-9 after optic nerve crush. These results show that BNB disruption and MMP-9 induction are differentially regulated in the PNS and CNS after injuries, and they may contribute to the different regeneration capacities of the two systems.
Assuntos
Barreira Hematoencefálica/enzimologia , Metaloproteinase 9 da Matriz/metabolismo , Traumatismos do Nervo Óptico/metabolismo , Nervo Óptico/enzimologia , Nervo Isquiático/enzimologia , Nervo Isquiático/lesões , Animais , Barreira Hematoencefálica/patologia , Matriz Extracelular/enzimologia , Imunoglobulina G/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Compressão Nervosa , Proteínas de Neurofilamentos/metabolismo , Nervo Óptico/patologia , Traumatismos do Nervo Óptico/patologia , Nervo Isquiático/patologiaRESUMO
Arecanut is a sort of palm that is important economic crop for the farmers in Hainan province of China, wherein there are many kinds of metal elements such as K, Ca, Na, Mg, Fe, Mn, Cu, Zn etc. These elements are important nutrition for the growth of arecanut. It is very valuable to study on the content of these metal elements in arecanut leaf in terms of plant nutriology of arecanut. The arecanut leaf in Wangling county, Hainan province of China was sampled by diagonal-field-sampling method. Refering to other plant sample determination by FAAS, the detailed studies are done with different digestion and determination methods. In the present paper the effects of mixed acid of HNO3-HClO4 digestion method on determining the amount of metal elements in the arecanut leaf by FAAS is reported, and another one is incineration digestion method. FAAS method was established for the determination of K, Ca, Mg, Na, Fe, Mn, Cu and Zn The samples were incinerated or heated with HNO3-HClO4 (4:1). In the meantime, the optimum parameters of FAAS and effects of different digestion methods on the results were discussed. The recovery rate of standard addition is 98.36%-102.38% in the first method; RSD is 0.42%-2.328% (n=6); The recovery rate of standard addition is 99.22%-103.72% in the second method; RSD is 0.58%-1.283 (n=6). The metal amount determined by the first method is lower than the second method, the ratio is 0.9703-0.9934. The two methods are satisfied, but the latter is better. It is precise enough to common experiment to use flame atomic absorption spectrophotometry with digestion by incineration If the especially precise experiment is required, the digestion methods with mixed acid of HNO3-HClO4 may be introduced. The paper introduced methods dependable for determination of some metal elements in order to study on some nutrient effects of these metal elements in arecanut.