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1.
Reprod Domest Anim ; 59(1): e14512, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38069628

RESUMO

Lambda light chains (λ-LCs) are frequently responsible for triggering the activation of inflammatory factors in autoimmune disorders, and an increase in their levels will cause various pathological changes in serum. The aim of this study was to determine the histological differences between the epididymis and testis of normal and cryptorchid Bactrian camels and the differences in λ-LC expression in the epididymis and testis of normal and cryptorchid Bactrian camels. Haematoxylin and eosin (H&E) staining was used to examine the pathological changes in cryptorchidism. The gene and protein levels of λ-LC were determined using RT-qPCR and western blot. The distribution of λ-LCs was assessed by immunohistochemistry and immunofluorescence. Compared with that in normal Bactrian camels, the diameter of the epididymal lumen and the thickness of the epithelium were decreased in the epididymis of cryptorchidic animals. Additionally, no sperm was detected in the cavity of the cryptorchidic epididymis. Meanwhile, the expression of λ-LC was significantly increased in the cryptorchidic epididymis at both the mRNA and protein levels (p < .05). The highest protein expression of λ-LC was found in epididymal epithelial halo cells and testicular Sertoli cells. These findings suggested that the structural changes observed in the epididymal epithelium of cryptorchidic camels affect its secretory and absorptive functions. Additionally, the high level of λ-LC expression recorded in halo cells suggested that these cells play an important role in epithelial immunity in cryptorchidic Bactrian camels. Furthermore, the high λ-LC expression levels detected in normal testicular Sertoli cells indicated that λ-LCs may be involved in spermatogenesis. The results of this study provide clues for an in-depth study of immunological sterility in cryptorchidic Bactrian camels.


Assuntos
Criptorquidismo , Epididimo , Masculino , Animais , Epididimo/metabolismo , Criptorquidismo/metabolismo , Criptorquidismo/veterinária , Camelus , Imunoglobulinas/metabolismo
2.
Molecules ; 29(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38257373

RESUMO

The impact of the chalcogen atomic electronegativity (O, S, and Se atoms) of new organic molecules on excited-state dynamical reactions is self-evident. Inspired by this kind of distinguished photochemical characteristic, in this work, we performed a computational investigation of chalcogen-substituted 3,6-bis(4,5-dihydroxyoxazo-2-yl)benzene-1,2-diol (BDYBD) derivatives (i.e., BDYBD-O, BDYBD-S, and BDYBD-Se). In this paper, we pay close attention to characteristic BDYBD derivatives that contain intramolecular double hydrogen bonds (O1-H2···N3 and O4-H5···N6). The main goal of this study was to explore how changes in atomic electronegativity affect the way hydrogen bonds interact and how excited molecules affect transfer protons. We go into further detail in the main text of the paper. By fixing our attention to geometrical variations and infrared (IR) vibrational spectra between the S0 and S1 states, exploring hydrogen bonding behaviors using the core-valence bifurcation (CVB) index, and simulating hydrogen bonding energy (EHB) via the atom in molecule (AIM) method, we clarified the photo-induced strengthened dual hydrogen bonding interactions that facilitate the excited-state dual-proton transfer (ESDPT) behavior of BDYBD derivatives. The reorganization of charge stemming from photoexcitation further verifies the tendencies of ESDPT reactions. We relied on constructing potential energy surfaces (PESs) by adopting a restrictive optimization approach, and herein, we finally clarify the gradual ESDPT mechanism of BDYBD derivatives. Particularly, we confirm that the variation in chalcogen atomic electronegativity has a regulatory effect on the ESDPT behavior of BDYBD derivatives; that is, the lower the atomic electronegativity, the more favorable it is for the gradual ESDPT reaction.

3.
Regul Toxicol Pharmacol ; 128: 105097, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34902532

RESUMO

In forensic toxicology, a marker of street heroin use is urgent especially in the absence of urinary 6-monoacetylmorphine. ATM4G, the Glucuronide of Acetylated product of Thebaine compound 4 Metabolite (ATM4), arising from byproducts of street heroin synthesis has been considered as a useful marker in some European studies. However, whether ATM4G is a universal marker particularly in Southeast Asia due to 'street' heroin with high purity, it's still unclear. To investigate putative markers for different regions, ATM4G and other metabolites including the Acetylated product of Thebaine compound 3 Metabolite (ATM3) and thebaol, also originated from thebaine were detected in 552 urine samples from heroin users in Taiwan. Results were compared with that from samples collected in the UK and Germany. Only a sulfo-conjugate of ATM4, ATM4S, was detected in 28 Taiwanese users using a sensitive MS3 method whilst out of 351 samples from the UK and Germany, ATM4G was present in 91. Thebaol-glucuronide was first time detected in 118. No markers were detected in urine following herbal medicine use or poppy seed ingestion. The presence of ATM4S/ATM4G might be affected by ethnicities and heroin supplied in regions. Thebaol-glucuronide is another putative marker with ATM4G and ATM4S for street heroin use.


Assuntos
Toxicologia Forense/métodos , Glucuronídeos/urina , Heroína/metabolismo , Detecção do Abuso de Substâncias/métodos , Sudeste Asiático , Europa (Continente) , Cromatografia Gasosa-Espectrometria de Massas/métodos , Heroína/urina , Humanos , Derivados da Morfina/urina , Tebaína/urina
4.
Reprod Domest Anim ; 56(5): 725-735, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33544931

RESUMO

Ziwuling black goats are typically found in loess plateaus regions and the Ziwuling Nature Reserve. Cryptorchidism is a common disease in this inbred goat, and its pathogenesis has been linked with the expression of insulin-like factor 3 (INSL-3). Therefore, this study aimed to investigate anatomical alterations caused by cryptorchism and the expression and distribution of INSL-3 in normal and cryptorchid testicular tissues. The testicular tissues of 6-month-old Ziwuling black goats were collected for microscopic analyses using histochemical, immunohistochemical, immunofluorescence and biometrical methods, as well as Western blotting to compare the expression and distribution of INSL-3. A lower expression of INSL-3 was observed in cryptorchid compared with normal testicular tissues (p < .01). Cryptorchidism caused a significant reduction in layers of spermatogenic epithelium and tubule areas in Ziwuling black goat (p < .01). The interstitial to seminiferous tubule area ratio was larger in cryptorchid than in normal group. Periodic Acid-Schiff (PAS) staining revealed pronounced positive bands in the interstitial tissue, while positive Alcian blue (AB) staining was not clear, and AB-PAS staining revealed a positive red band in the basement membrane of cryptorchid group. Immunofluorescence revealed a strong signal of INSL-3 expression in Sertoli and peritubular myoid cells, and moderate signal in Leydig and spermatogenic cells in the normal group. However, in cryptorchid testicular tissues, the signal of INSL-3 expression was strong in primary spermatocytes, occasional in Sertoli cells, limited in Leydig cells and absent in peritubular myoid cells. Furthermore, immunohistochemistry showed that INSL-3 expression was higher in normal testes compared with cryptorchid testicular tissues (p < .05), especially in primary spermatocytes and Sertoli cells. Collectively, our results indicate that cryptorchidism is closely related to the disorder of acid glycoprotein metabolism and the reduction in release of INSL-3 from Leydig cells. Moreover, Sertoli and peritubular myoid cells are crucial for INSL signalling and could underpin further research on the mechanism of cryptorchidism in animal.


Assuntos
Criptorquidismo/veterinária , Insulina/metabolismo , Testículo/metabolismo , Animais , Criptorquidismo/metabolismo , Criptorquidismo/patologia , Doenças das Cabras , Cabras , Células Intersticiais do Testículo , Masculino , Proteínas/metabolismo , Relaxina/metabolismo , Células de Sertoli/metabolismo
5.
Anticancer Drugs ; 31(9): 908-917, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32097138

RESUMO

Hepatocellular carcinoma is the second leading cause of cancer-related death worldwide. Neural regulation plays an important role in the development of hepatocellular carcinoma, and activation of sympathetic nervous system can promote the migration and invasion of cancer cells. However, little research has been conducted on how the vagus nerve influences hepatocellular carcinoma. In this study, we found that the expression of vesicular acetylcholine transporter, a biomarker of vagus nerve, was associated with hepatocellular carcinoma patients' clinicopathological characteristics by immunohistochemistry. Further, activation of muscarinic acetylcholine receptor 1 (M1R) promoted HepG2 and SMMC-7721 cells migration and invasion and epithelial-mesenchymal transition via PI3K/Akt pathway. Moreover, inhibition of M1R by antagonist or shRNA suppressed hepatocellular carcinoma cells migration and invasion in vitro and in vivo, inhibited epithelial-mesenchymal transition and PI3K/Akt pathway. Therefore, these results indicate that activation of M1R promotes invasion of hepatocellular carcinoma through epithelial-mesenchymal transition and PI3K/Akt pathway.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Receptor Muscarínico M1/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Transição Epitelial-Mesenquimal , Feminino , Células Hep G2 , Xenoenxertos , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Nervo Vago/patologia
6.
Rapid Commun Mass Spectrom ; 34 Suppl 1: e8579, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31502287

RESUMO

RATIONALE: The presence of α-pyrrolidinovalerophenone (α-PVP) and its metabolites in urine is evidence of the administration of α-PVP. A toxicological challenge is that the metabolites of α-PVP exhibit amphoteric properties, which make them unsuitable for detection using gas chromatography-mass spectrometry (GC/MS). In the study reported, proper derivatization and sample extraction were essential for improving the sensitivity for GC/MS analysis. METHODS: An automated solid-phase extraction (SPE) method has been developed and optimized. The derivatization efficiency was tested using longer reaction time and the addition of polar pyridine into a mixture of N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane. Method validation, including linearity, limit of detection, precision, accuracy, and recovery, was evaluated using automatic SPE and GC/MS. RESULTS: The results suggested that adding pyridine to BSTFA (1:1, v/v) significantly improved derivatization efficiency and precision. After optimization, the linear range was from 25 to 1000 ng mL-1 with R2 > 0.9950. The limit of detection was 5 ng mL-1 for α-PVP and 25 ng mL-1 for OH-α-PVP. The recovery for SPE was over 88%. The inter-day and intra-day precisions were less than 15%. A forensic sample has been found containing α-PVP (67.3 ng mL-1 ) and OH-α-PVP (560.2 ng mL-1 ). CONCLUSIONS: This study is the first to validate an auto-SPE-GC/MS method for the quantification and qualification of α-PVP and OH-α-PVP in urine. We have successfully improved the derivatization efficiency and developed a sensitive and semi-automatic approach. This approach is desirable for the detection of synthetic cathinone at trace levels in biological samples.


Assuntos
Alcaloides/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Pirrolidinas/urina , Alcaloides/metabolismo , Drogas Desenhadas/metabolismo , Drogas Desenhadas/farmacocinética , Humanos , Limite de Detecção , Pirrolidinas/metabolismo , Extração em Fase Sólida/métodos , Detecção do Abuso de Substâncias/métodos
7.
Small ; 15(9): e1805453, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30690897

RESUMO

Artificial skin devices are able to mimic the flexibility and sensory perception abilities of the skin. They have thus garnered attention in the biomedical field as potential skin replacements. This Review delves into issues pertaining to these skin-deep devices. It first elaborates on the roles that these devices have to fulfill as skin replacements, and identify strategies that are used to achieve such functionality. Following which, a comparison is done between the current state of these skin-deep devices and that of natural skin. Finally, an outlook on artificial skin devices is presented, which discusses how complementary technologies can create skin enhancements, and what challenges face such devices.


Assuntos
Pele Artificial , Pele , Materiais Biocompatíveis , Humanos , Engenharia Tecidual
8.
Exp Brain Res ; 237(2): 291-311, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30506366

RESUMO

The development of advanced and effective human-machine interfaces, especially for amputees to control their prostheses, is very high priority and a very active area of research. An intuitive control method should retain an adequate level of functionality for dexterous operation, provide robustness against confounding factors, and supply adaptability for diverse long-term usage, all of which are current problems being tackled by researchers. This paper reviews the state-of-the-art, as well as, the limitations of current myoelectric signal control (MSC) methods. To address the research topic on functionality, we review different approaches to prosthetic hand control (DOF configuration, discrete or simultaneous, etc.), and how well the control is performed (accuracy, response, intuitiveness, etc.). To address the research on robustness, we review the confounding factors (limb positions, electrode shift, force variance, and inadvertent activity) that affect the stability of the control performance. Lastly, to address adaptability, we review the strategies that can automatically adjust the classifier for different individuals and for long-term usage. This review provides a thorough overview of the current MSC methods and helps highlight the current areas of research focus and resulting clinic usability for the MSC methods for upper-limb prostheses.


Assuntos
Membros Artificiais , Interfaces Cérebro-Computador , Eletromiografia , Fenômenos Eletrofisiológicos , Atividade Motora , Músculo Esquelético , Humanos , Atividade Motora/fisiologia , Músculo Esquelético/fisiologia
9.
Macromol Rapid Commun ; 40(5): e1800216, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30085362

RESUMO

As a herb of the ginger family, the turmeric plant has been used as spice and colorant in the Oriental countries. The rhizome part of the plant is rich in curcumin, which has been proven to be the main ingredient responsible for turmeric's biological effects. Most research endeavors have been upon the investigation of pharmaceutical activities of curcumin, yet the fluorescence of curcumin is a bit far from well-studied. The major drawbacks associated with curcumin are its poor aqueous solubility and low stability. In this communication, the encapsulation of fluorescent turmeric extract into polymeric nanoparticles (NPs) for bioimaging and antibacterial applications is reported. Through poly(d,l-lactic-co-glycolic acid) (PLGA) encapsulation, solubility of curcumin is greatly increased, and the biodegradable nature of PLGA further enhances the biocompatibility of curcumin. These Cur-PLGA NPs are successfully demonstrated to be efficient fluorescence probes for bioimaging, and promising for antibacterial application.


Assuntos
Anti-Infecciosos/farmacologia , Diagnóstico por Imagem , Composição de Medicamentos , Extratos Vegetais/farmacologia , Polímeros/química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Curcuma/química , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Nanopartículas/química , Nanopartículas/ultraestrutura , Extratos Vegetais/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Staphylococcus aureus/efeitos dos fármacos
10.
Mikrochim Acta ; 186(7): 453, 2019 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-31201539

RESUMO

The authors describe a three-dimensional (3D) flexible interconnected porous nanocomposite membrane for use in surface-enhanced Raman scattering (SERS). It was obtained via in -situ deposition of gold nanoparticles (AuNPs, ca. 10 nm) on eggshell membranes (ESM). The AuNP/ESM nanocomposites were used as a SERS substrate for detection of the pesticide thiabendazole (TBZ) with prominent Raman bands at 1180, 1280, and 1580 cm-1. The abundant "hot spots" are generated by the closely arranged AuNPs in the 3D geometry of the ESM networks. This makes the SERS substrate highly sensitive because of remarkable signal amplification. The substrates were applied to the rapid detection of TBZ in Oolong tea. The limit of detection for TBZ is 0.1 ppm. Graphical abstract Schematic presentation of a three-dimensional flexible interconnected porous nanocomposite membrane as surface-enhanced Raman scattering (SERS) substrate for detection of thiabendazole (TBZ) in tea.

11.
Mikrochim Acta ; 185(7): 340, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29946815

RESUMO

The authors describe an amperometric sensor for dopamine (DA) by employing olive-like Fe2O3 microspheres (OFMs) as the electrocatalyst for DA oxidization. The OFMs were prepared by using a protein templated method. The structure and properties of the OFMs were characterized by scanning electron microscopy, X-ray powder diffraction, energy dispersive x-ray spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The OFMs possess excellent catalytic activity towards DA oxidization due to their unique morphology. The sensor responds to DA within less than 5 s. The sensor, best operated at a voltage of +0.2 V (vs. SCE) responds linearly in the 0.2 to 115 µM DA concentration range and has a 30 nM detection limit. The selectivity, reproducibility and long-term stability of the sensor are acceptable. It performs well when applied to spiked human urine samples. Graphical abstract Olive-like Fe2O3 microspheres (OFMs), synthesized using egg white as template, display excellent catalytic activity towards dopamine (DA) oxidization due to their unique morphology. They were applied for DA detection using the amperometric technique. The electrochemical sensor exhibited a high sensitivity and a 30 nM detection limit. DAQ: dopaquinone.


Assuntos
Técnicas Biossensoriais/métodos , Dopamina/análise , Proteínas do Ovo/química , Compostos Férricos/química , Limite de Detecção , Microesferas , Catálise , Dopamina/urina , Eletroquímica , Humanos
12.
Mikrochim Acta ; 185(7): 338, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29946991

RESUMO

A sandwich-type electrochemical cytosensor is described for quantitative determination of CD44-overexpressing HeLa cells. Hyaluronic acid (HA) acts as a targeting molecule that was in-situ incorporated into the sensor based on the use of an indium tin oxide (ITO) electrode modified with multi-walled carbon nanotubes (MWCNTs). The 3D-MWCNT structure is shown to strongly improve the electronic properties and surface chemical reactivities. The HA-modified sensor exhibits a highly sensitive response to HeLa cells. A sandwiched hybridization protocol was then established using BIO [an N-butyl-4-(6'-aminohexyl)amino-1,8-naphthalimide probe modified with HA] as the tracing labels of the fluorescent probes for targeting CD44-positive tumor cells. The signal amplification was thereby maximized and measured by chronocoulometry. The binding of CD44-positive HeLa cells to the HA modified sensing layer causes a decrease in chronocoulometric response. The signal decreases linearly in the 2.1 × 102 to 2.1 × 107 HeLa cells·mL-1 concentration range with a detection limit of 70 cells·mL-1. Such a sandwich-type assay may be tailored as a sensitive candidate for detecting low levels of tumor cells. Graphical abstract Schematic of a sandwich cytosensor based on hyaluronic acid-grafted 3D-MWCNT as biosensing interface and BIO as fluorescent probe. This biosensor possessed excellent electrochemical activity, high sensitivity and selectivity, providing a dynamical tracking and detecting platform for CD44-positive tumor cells.


Assuntos
Técnicas Biossensoriais/métodos , Colorimetria/métodos , Regulação Neoplásica da Expressão Gênica , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/química , Nanotubos de Carbono/química , Imagem Óptica/métodos , Linhagem Celular Tumoral , Humanos , Limite de Detecção
13.
Mikrochim Acta ; 185(10): 458, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30218157

RESUMO

A composite consisting of graphene oxide and gold nanorods (GO-GNRs) was designed for the trace determination of hepatitis B surface antigen (HBsAg) using surface enhanced Raman spectroscopy (SERS). GO contains numerous carboxy and hydroxy groups on its surface and therefore can serve as the substrate for decoration with GNRs and for immobilizing antibody against HBsAg. The GNRs (carrying the SERS probe 2-mercaptopyridine) exhibit high SERS activity, and this improves the sensitivity of the biosensor. The antibody on the GO-GNRs binds HBsAg with high specificity, and it results in excellent selectivity. The SERS signal (measured at 1002 cm-1) increases in the 1-1000 pg·mL-1 HBsAg concentrations range, and the limit of detection is 0.05 pg·mL-1 (at an S/N ratio of 3). The immunoassay achieves the sensitive and selective determination of HBsAg in serum and expands the potential application of GO-GNR based SERS tag in clinical research. Graphical abstract A novel graphene oxide-gold nanorod (GO-GNRs) based surface-enhanced Raman scattering (SERS) tag for immunoassay was designed. It allows for sensitive and selective determination of HBsAg in serum. The method is expected to expand the potential application in the environment, in medicine and in food analysis.


Assuntos
Ouro/química , Grafite/química , Antígenos de Superfície da Hepatite B/análise , Imunoensaio/métodos , Nanotubos/química , Óxidos/química , Análise Espectral Raman , Humanos , Modelos Moleculares , Conformação Molecular , Propriedades de Superfície
14.
Development ; 141(3): 514-25, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24449834

RESUMO

Transcription factors (TFs) pattern developing tissues and determine cell fates; however, how spatio-temporal TF gradients are generated is ill defined. Here we show that miR-335 fine-tunes TF gradients in the endoderm and promotes mesendodermal lineage segregation. Initially, we identified miR-335 as a regulated intronic miRNA in differentiating embryonic stem cells (ESCs). miR-335 is encoded in the mesoderm-specific transcript (Mest) and targets the 3'-UTRs of the endoderm-determining TFs Foxa2 and Sox17. Mest and miR-335 are co-expressed and highly accumulate in the mesoderm, but are transiently expressed in endoderm progenitors. Overexpression of miR-335 does not affect initial mesendoderm induction, but blocks Foxa2- and Sox17-mediated endoderm differentiation in ESCs and ESC-derived embryos. Conversely, inhibition of miR-335 activity leads to increased Foxa2 and Sox17 protein accumulation and endoderm formation. Mathematical modeling predicts that transient miR-335 expression in endoderm progenitors shapes a TF gradient in the endoderm, which we confirm by functional studies in vivo. Taken together, our results suggest that miR-335 targets endoderm TFs for spatio-temporal gradient formation in the endoderm and to stabilize lineage decisions during mesendoderm formation.


Assuntos
Linhagem da Célula/genética , Endoderma/citologia , Endoderma/metabolismo , Mesoderma/citologia , MicroRNAs/metabolismo , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Diferenciação Celular/genética , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Endoderma/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Proteínas HMGB/genética , Proteínas HMGB/metabolismo , Fator 3-beta Nuclear de Hepatócito/genética , Fator 3-beta Nuclear de Hepatócito/metabolismo , Mesoderma/embriologia , Mesoderma/metabolismo , Camundongos , MicroRNAs/genética , Modelos Biológicos , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Fatores de Transcrição SOXF/genética , Fatores de Transcrição SOXF/metabolismo , Análise Espaço-Temporal
16.
Brain Behav Immun ; 59: 118-134, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27585737

RESUMO

The sympathetic nervous system (SNS) is known to play a significant role in tumor initiation and metastasis. Hepatocellular carcinoma (HCC) frequently occurs in cirrhotic livers after chronic inflammation, and the SNS is hyperactive in advanced liver cirrhosis. However, it remains unclear whether the SNS promotes hepatocarcinogenesis by modulating chronic liver inflammation. In this study, a retrospective pathological analysis and quantification of sympathetic nerve fiber densities (tyrosine hydroxylase, TH+) in HCC patients, and diethylnitrosamine (DEN)-induced hepatocarcinogenesis in rats were performed. Our data showed that high density of sympathetic nerve fibers and α1-adrenergic receptors (ARs) of Kupffer cells (KCs) were associated with a poor prognosis of HCC. Sympathetic denervation or blocking of α1-ARs decreased DEN-induced HCC incidence and tumor development. In addition, synergistic effects of interleukin-6 (IL-6) and transforming growth factor-beta (TGF-ß) in hepatocarcinogenesis were observed. The suppression of the SNS reduced IL-6 and TGF-ß expression, which suppressed hepatocarcinogenesis, and KCs play a key role in this process. After the ablation of KCs, IL-6 and TGF-ß expression and the development of HCC were inhibited. This study demonstrates that sympathetic innervation is crucial for hepatocarcinogenesis and that the SNS promotes hepatocarcinogenesis by activating α1-ARs of KCs to boost the activation of KCs and to maintain the inflammatory microenvironment. These results indicate that sympathetic denervation or α1-ARs blockage may represent novel treatment approaches for HCC.


Assuntos
Carcinogênese/patologia , Carcinoma Hepatocelular/patologia , Inflamação/patologia , Células de Kupffer , Neoplasias Hepáticas/patologia , Receptores Adrenérgicos alfa 1 , Sistema Nervoso Simpático/patologia , Adulto , Idoso , Animais , Feminino , Humanos , Interleucina-6/metabolismo , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/patologia , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Prognóstico , Ratos , Ratos Sprague-Dawley , Estudos Retrospectivos , Fator de Crescimento Transformador beta/biossíntese
17.
Macromol Rapid Commun ; 38(21)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28895248

RESUMO

With the advancement of polymer engineering, complex star-shaped polymer architectures can be synthesized with ease, bringing about a host of unique properties and applications. The polymer arms can be functionalized with different chemical groups to fine-tune the response behavior or be endowed with targeting ligands or stimuli responsive moieties to control its physicochemical behavior and self-organization in solution. Rheological properties of these solutions can be modulated, which also facilitates the control of the diffusion of the drug from these star-based nanocarriers. However, these star-shaped polymers designed for drug delivery are still in a very early stage of development. Due to the sheer diversity of macromolecules that can take on the star architectures and the various combinations of functional groups that can be cross-linked together, there remain many structure-property relationships which have yet to be fully established. This review aims to provide an introductory perspective on the basic synthetic methods of star-shaped polymers, the properties which can be controlled by the unique architecture, and also recent advances in drug delivery applications related to these star candidates.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas/química , Polímeros/química , Animais , Humanos , Preparações Farmacêuticas/química , Polimerização , Polímeros/síntese química
18.
Phys Chem Chem Phys ; 19(23): 15021-15029, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28555221

RESUMO

First principles calculations based on density functional theory were carried out to study the electronic and magnetic properties of C2N nanoribbons (C2NNRs). The electronic structure could be modified by different methods using saturated or co-saturated H, O, and F on the edges, which can provide a new pathway at the nanoscale for fabricating 2D spintronic materials. It was found that the pristine armchair C2NNR (A-C2NNR) is a nonmagnetic semiconductor with a direct band gap, while the pristine zigzag C2NNRs (Z-C2NNRs) can show either magnetic semiconductor with an indirect band gap or magnetic metallic behavior depending on its ribbon widths. A-C2NNRs with one type of atom (H, O or F) saturated on the edges are nonmagnetic, while H and O (F and O) co-saturated A-C2NNRs show magnetic ground states. H and O (F and O) co-saturated Z-C2NNRs share a larger magnetic moment compared to the case with H, O and F saturated on the edges. Furthermore, O-saturated Z-C2NNR is a spin "gapless" semiconductor. Additionally, there is no need to spin flip in the process of electronic transition near the Fermi level. Therefore, C2NNRs might have potential applications in photoelectronic and spinelectronic devices.

19.
Mikrochim Acta ; 185(1): 8, 2017 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-29594443

RESUMO

Fluorescent iridium nanoclusters (IrNCs) consisting of up to 7 Ir atoms were prepared by heating IrCl3 in N,N-dimethylformamide. No other reagents are required. High resolution transmission electron microscopy (HRTEM) shows the IrNCs to be monodispersed with an average size of 0.9 ± 0.2 nm. They are well soluble in polar solvents and stable in these solvents for at least 6 months. Under photoexcitation with 365 nm light, they emit strong bluish green fluorescence with peaks that depend on the excitation wavelength and range from 530 to 650 nm. The fluorescence lifetime typically is 2.2 ns and the quantum yield is 8.3%. Fluorescence is quenched by Cr(VI) ion (chromate), and the emission peak is gradually red-shifted. According to the absorbance spectra of IrNCs in the presence and absence of Cr(VI) and Stern-Volmer quenching behavior study, static quenching is involved. Based on these findings, a selective assay was developed for the determination of Cr(VI). It has a linear response in the 0.1 to 100 µM chromate concentration range and a 25 nM detection limit. Graphic abstract Fluorescent iridium nanoclusters (IrNCs), consisting of up to 7 Ir atoms, were prepared in N,N-dimethylformamide (DMF) solution without using any other reagents. Their fluorescence is statically quenched by Cr(VI).

20.
Sensors (Basel) ; 17(6)2017 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-28608824

RESUMO

Performance degradation will be caused by a variety of interfering factors for pattern recognition-based myoelectric control methods in the long term. This paper proposes an adaptive learning method with low computational cost to mitigate the effect in unsupervised adaptive learning scenarios. We presents a particle adaptive classifier (PAC), by constructing a particle adaptive learning strategy and universal incremental least square support vector classifier (LS-SVC). We compared PAC performance with incremental support vector classifier (ISVC) and non-adapting SVC (NSVC) in a long-term pattern recognition task in both unsupervised and supervised adaptive learning scenarios. Retraining time cost and recognition accuracy were compared by validating the classification performance on both simulated and realistic long-term EMG data. The classification results of realistic long-term EMG data showed that the PAC significantly decreased the performance degradation in unsupervised adaptive learning scenarios compared with NSVC (9.03% ± 2.23%, p < 0.05) and ISVC (13.38% ± 2.62%, p = 0.001), and reduced the retraining time cost compared with ISVC (2 ms per updating cycle vs. 50 ms per updating cycle).


Assuntos
Reconhecimento Automatizado de Padrão , Algoritmos , Eletromiografia , Aprendizado de Máquina
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