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1.
Nature ; 630(8016): 346-352, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38811731

RESUMO

Vertical three-dimensional integration of two-dimensional (2D) semiconductors holds great promise, as it offers the possibility to scale up logic layers in the z axis1-3. Indeed, vertical complementary field-effect transistors (CFETs) built with such mixed-dimensional heterostructures4,5, as well as hetero-2D layers with different carrier types6-8, have been demonstrated recently. However, so far, the lack of a controllable doping scheme (especially p-doped WSe2 (refs. 9-17) and MoS2 (refs. 11,18-28)) in 2D semiconductors, preferably in a stable and non-destructive manner, has greatly impeded the bottom-up scaling of complementary logic circuitries. Here we show that, by bringing transition metal dichalcogenides, such as MoS2, atop a van der Waals (vdW) antiferromagnetic insulator chromium oxychloride (CrOCl), the carrier polarity in MoS2 can be readily reconfigured from n- to p-type via strong vdW interfacial coupling. The consequential band alignment yields transistors with room-temperature hole mobilities up to approximately 425 cm2 V-1 s-1, on/off ratios reaching 106 and air-stable performance for over one year. Based on this approach, vertically constructed complementary logic, including inverters with 6 vdW layers, NANDs with 14 vdW layers and SRAMs with 14 vdW layers, are further demonstrated. Our findings of polarity-engineered p- and n-type 2D semiconductor channels with and without vdW intercalation are robust and universal to various materials and thus may throw light on future three-dimensional vertically integrated circuits based on 2D logic gates.

2.
RSC Adv ; 14(13): 9114-9121, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38500617

RESUMO

Creatinine is an important biomarker for the diagnosis of chronic kidney disease (CKD). Recently, it has been reported that the concentration of salivary creatinine correlates well with the concentration of serum creatinine, which makes the former useful for the development of non-invasive and point-of-care (POC) detection for CKD diagnosis. However, there exists a technical challenge in the rapid detection of salivary creatinine at low concentrations of 3-18 µM when using the current kidney function test strips as well as the traditional methods employed in hospitals. Herein, we demonstrate a simple, sensitive colorimetric assay for the detection of creatinine with a limit-of-detection (LOD) down to the nanomolar level. Our approach utilises the dual binding affinity of creatinine for citrate-capped silver nanoparticles (Ag NPs) and Ag(i) ions, which can trigger the aggregation of Ag NPs and thus lead to the colour change of a sample. The quantitative detection of creatinine was achieved using UV-Vis spectroscopy with a LOD of 6.9 nM in artificial saliva and a linear dynamic range of 0.01-0.06 µM. This method holds promise to be further developed into a POC platform for the CKD diagnosis.

3.
Nano Lett ; 23(24): 11850-11859, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38051785

RESUMO

Cardiac oxidative stress is a significant phenotype of myocardial infarction disease, a leading cause of global health threat. There is an urgent need to develop innovative therapies. Nanosized extracellular vesicle (nEV)-based therapy shows promise, yet real-time monitoring of cardiomyocyte responses to nEVs remains a challenge. In this study, a dynamic and label-free cardiomyocyte biosensing system using microelectrode arrays (MEAs) was constructed. Cardiomyocytes were cultured on MEA devices for electrophysiological signal detection and treated with nEVs from E. coli, gardenia, HEK293 cells, and mesenchymal stem cells (MSC), respectively. E. coli-nEVs and gardenia-nEVs induced severe paroxysmal fibrillation, revealing distinct biochemical communication compared to MSC-nEVs. Principal component analysis identified variations and correlations between nEV types. MSC-nEVs enhanced recovery without inducing arrhythmias in a H2O2-induced oxidative stress injury model. This study establishes a fundamental platform for assessing biochemical communication between nEVs and cardiomyocytes, offering new avenues for understanding nEVs' functions in the cardiovascular system.


Assuntos
Peróxido de Hidrogênio , Miócitos Cardíacos , Humanos , Células HEK293 , Peróxido de Hidrogênio/metabolismo , Escherichia coli , Arritmias Cardíacas , Estresse Oxidativo
4.
Food Chem ; 429: 136822, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37450994

RESUMO

Cyclodextrins, with their unparalleled attributes of eco-friendliness, natural abundance, versatile utility, and facile functionalization, make a paramount contribution to the field of molecular imprinting. Leveraging the unique properties of cyclodextrins in molecularly imprinted polymers synthesis has revolutionized the performance of molecularly imprinted polymers, resulting in enhanced adsorption selectivity, capacity, and rapid extraction of pesticides, while also circumventing conventional limitations. As the concern for food quality and safety continues to grow, the need for standard analytical methods to detect pesticides in food and environmental samples has become paramount. Cyclodextrins, being non-toxic and biodegradable, present an attractive option for greener reagents in imprinting polymers that can also ensure environmental safety post-application. This review provides a comprehensive summary of the significance of cyclodextrins in molecular imprinting for pesticide detection in food and environmental samples. The recent advancements in the synthesis and application of molecularly imprinted polymers using cyclodextrins have been critically analyzed. Furthermore, the current limitations have been meticulously examined, and potential opportunities for greenification with cyclodextrin applications in this field have been discussed. By harnessing the advantages of cyclodextrins in molecular imprinting, it is possible to develop highly selective and efficient methods for detecting pesticides in food and environmental samples while also addressing the challenges of sustainability and environmental impact.


Assuntos
Ciclodextrinas , Impressão Molecular , Praguicidas , Polímeros Molecularmente Impressos , Extração em Fase Sólida
5.
Biosens Bioelectron ; 220: 114844, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36332336

RESUMO

A novel colorimetric biosensor was explored for fast, sensitive, and on-site detection of Salmonella on a microfluidic chip employing immune gold@platinum nanoparticles (Au@Pt NPs) for specific bacterial labeling, a finger-driven mixer with two serial air chambers for efficient immunoreaction and a nuclear track membrane as specific-size microfilter for effective bacterial isolation from excessive immune Au@Pt NPs. First, the bacterial sample and immune Au@Pt NPs were pipetted into the mixing chamber and mixed sufficiently through repeated press-release actions on the small air chamber which could precisely control the air volume, leading to the formation of bacteria-immune Au@Pt NP conjugates. Then, the small and large air chambers were pressed simultaneously to push all the solution in the mixing chamber to flow through the microfilter for trap of the formed larger-size conjugates on the membrane and removal of the unbound smaller-size immune Au@Pt NPs. After the H2O2-TMB substrate was pipetted into the microfilter and catalyzed by the conjugates, ImageJ was used to analyze the color change for bacterial determination. This simple biosensor enabled Salmonella detection as low as 168 CFU/mL in 25 min.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Platina , Microfluídica , Peróxido de Hidrogênio , Ouro , Salmonella
6.
Front Chem ; 10: 905105, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711960

RESUMO

We herein reported the first chemoenzymatic synthesis of lacto-N-hexaose (LNH) by combining chemical carbohydrate synthesis with a selectively enzymatic glycosylation strategy. A tetrasaccharide core structure GlcNH2ß1→3 (GlcNAcß1→6) Galß1→4Glc, a key precursor for subsequent enzymatic glycan extension toward asymmetrically branched human milk oligosaccharides, was synthesized in this work. When the order of galactosyltransferase-catalyzed reactions was appropriately arranged, the ß1,4-galactosyl and ß1,3-galactosyl moieties could be sequentially assembled on the C6-arm and C3-arm of the tetrasaccharide, respectively, to achieve an efficient LNH synthesis. Lacto-N-neotetraose (LNnH), another common human milk oligosaccharide, was also synthesized en route to the target LNH.

7.
J Sep Sci ; 45(20): 3900-3908, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35708024

RESUMO

Astaxanthin with high antioxidant activity is of great practical value and Haematococcus pluvialis is recognized as the best natural astaxanthin producer. The yield of Haematococcus pluvialis was often affected by the ciliate during its production, however, the use of biochemical pesticides might have a great impact on Haematococcus pluvialis. Therefore, a simple microfluidic chip with the spiral microchannel was developed for continuous-flow physical separation of ∼10 µm ciliate from ∼30 µm Haematococcus pluvialis since their different sizes resulted in different equilibrium positions in the channel due to the Dean-coupled inertial migration. First, a spiral microchannel with a width of 700 µm and a height of 130 µm in the microfluidic chip was developed using three-dimensional printing and verified to completely separate polystyrene particles of 10 µm from those of 30 µm. Then, this microfluidic chip was used to separate the actual sample, and experimental results showed that ∼80% of ciliate was continuously separated from Haematococcus pluvialis at a flow rate of 2.8 ml/min. More importantly, no additional biochemical reagents were used and the activity of Haematococcus pluvialis was not affected. This microfluidic chip featured with simple design, automatic operation, and small size is promising for purification and breeding of Haematococcus pluvialis.


Assuntos
Microfluídica , Xantofilas
8.
RSC Adv ; 10(48): 28746-28754, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35520072

RESUMO

Thaumatin-like protein-1 (TLP-1), a protein displaying high polyphenol oxidase (PPO) action and a member of the pathogenesis-related (PR) protein family, has a considerable influence on the enzymatic browning of Prunus mume (Chinese plum). In this assay, TLP-1 was identified and extracted from Prunus mume to investigate the protein's properties and better understand its contribution to the fruit's browning during storage or processing. The extracted TLP-1 was purified to apparent homogeneity using a procedure involving citrate phosphate buffer solution (CPBS) extraction, (NH4)2SO4 precipitation, dialysis in a cellulose bag, and ion exchange chromatography using a DEAE Sepharose Fast Flow column, while a Sephadex G-75 column was employed to facilitate gel filtration chromatography. Moreover, the enzyme was characterized in terms of its optimal pH and stability, isoelectric point (pI), molecular weight, optimal temperature and stability, enzyme kinetic parameters and substrate specificity, as well as inhibitor stability. This study indicated that the pI and molecular weight of TLP-1 was approximately 4.4 and 28 kDa, respectively, while 30 °C and 7.5 represented the respective optimal temperature and pH level for PPO catalysis. TLP-1 showed high affinity to catechol and pyrogallol, with K m values of 24.40 mM and 26.23 mM, respectively. Sodium bisulfite significantly inhibited TLP-1 activity. These findings on the properties of TLP-1 can contribute significantly to the search for ways to minimize the losses caused by fruit browning during the storage and processing of Prunus mume.

9.
Biomed Res Int ; 2016: 5139651, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27803925

RESUMO

Objective. To observe the curative effect of VAWI on Xinjiang Uygur patients with silicosis fibrosis. Methods. After we diagnosed the 40 patients with the first phase of silicosis, we randomly divided them into two groups: the basic treatment group (group A, n = 20) and the VAWI group (group B, n = 20). At the same time, we selected the age-matched healthy patients (n = 20). We applied the combined protein chip with SELDI-TOF-MS to carry out the serum analysis. The data were analyzed throughout data preprocessing, difference in PEAK screening, hierarchical cluster analysis, and Principal Component Analysis (PCA). We built decision tree model and predict the difference between the PEAK corresponding proteins. Results. The proteins peaks corresponding to name, predicted protein, and gene name were as follows: M2001_69, amyloid beta a4 protein, APP, and M2017_02, amyloid beta a4 protein, APP. The different expression of proteins in patients with silicosis was found before and after with VAWI treatment. The predicted proteins were as follows: M1982_50, amyloid beta a4 protein, APP; M3164_50, fibrinogen alpha chain frag, FGA; M3379_28, fibrinogen alpha chain frag, FGA; and so on. Conclusion. VAWI presented curative effect on patients with silicosis fibrosis via the alternation of proteins expression in serum.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Fibrose Pulmonar/complicações , Fibrose Pulmonar/tratamento farmacológico , Silicose/complicações , Silicose/tratamento farmacológico , Vernonia/química , Análise por Conglomerados , Árvores de Decisões , Análise Discriminante , Humanos , Injeções , Análise dos Mínimos Quadrados , Análise de Componente Principal
10.
Zhonghua Nan Ke Xue ; 21(8): 681-6, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26442292

RESUMO

OBJECTIVE: To explore the possible pain mechanism of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). METHODS: The models of CP/CPPS were established in male Wistar rats by the autoimmune method. The paw withdrawal threshold (PWT) was detected using Von Frey filament. The expressions of the substance P and c-fos in the prostate and spinal L5-S2 segments were determined by immunohistochemistry followed by analysis of their correlation with CP/CPPS. RESULTS: Compared with the control rats, the CP/CPPS models showed significantly decreased PWT (P < 0.05), remarkable prostatic inflammation, enlarged scope of lesions, and obvious interstitial lymphocytic infiltration (P < 0.05). Both the expressions of substance P and c-fos were markedly elevated in the prostate and spinal dorsal horn (L5-S2) of the rat models (P < 0.05), but the expression of substance P in the prostate exhibited no correlation with that in the spinal cord (r = 0.099, P = 0.338), nor did that of c-fos (r = 0.027, P = 0.454). CONCLUSION: The upregulated expressions of substance P and c-fos in the spinal cord L5-S2 sections may be associated with the pain mechanism of CP/CPPS.


Assuntos
Dor Pélvica/etiologia , Próstata/metabolismo , Prostatite/complicações , Proteínas Proto-Oncogênicas c-fos/metabolismo , Medula Espinal/metabolismo , Substância P/metabolismo , Animais , Doença Crônica , Imuno-Histoquímica , Masculino , Dor Pélvica/metabolismo , Prostatite/metabolismo , Ratos , Ratos Wistar , Síndrome , Regulação para Cima
11.
Zhonghua Nan Ke Xue ; 21(2): 107-12, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25796681

RESUMO

OBJECTIVE: To study the possible mechanisms of chronic nonbacterial prostatitis (CNP) pain. METHODS: CNP models were established in male Wistar rats by the autoimmune method. Then the paw withdrawal threshold (PWT) was detected using the Von Frey filament, prostate pathological examination was conducted, the expressions of substance P (SP) and transient receptor potential vanilloid 1 (TRPV1) in the prostate tissue and L5-S2 spinal segments were determined by immunohistochemistry and their correlations were analyzed. RESULTS: Compared with the control group, the CNP model rats showed markedly decreased PWT (P < 0.05) and obvious inflammation in the prostate tissue, with significant differences in the scope of lesion and interstitial lymphocyte infiltration (P < 0.05). The expressions of SP and TRPV1 in the prostate and spinal cord dorsal horn L5-S2 were remarkably upregulated in the models as compared with the control rats (P < 0.05). However, the expression of SP in the prostate was not correlated with that in the spinal cord (r = 0.099, P = 0.338), nor was that of TRPV1 (r = 0.000, P = 0.5). CONCLUSION: SP and TRPV1 were involved in the formation and persistence of pain in CNP rats through their upregulated expressions in the L5-S2 spinal segments.


Assuntos
Neuralgia/metabolismo , Dor/metabolismo , Prostatite/metabolismo , Medula Espinal/metabolismo , Substância P/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Região Lombossacral , Masculino , Neuralgia/fisiopatologia , Dor/fisiopatologia , Próstata/metabolismo , Prostatite/fisiopatologia , Ratos , Ratos Wistar
12.
Environ Monit Assess ; 186(2): 1253-60, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24097011

RESUMO

Generic Escherichia coli was isolated from surface water and groundwater samples from two dairies in Northern California and tested for susceptibility to antibiotics. Surface samples were collected from flush water, lagoon water, and manure solids, and groundwater samples were collected from monitoring wells. Although E. coli was ubiquitous in surface samples with concentrations ranging from several hundred thousand to over a million colony-forming units per 100 mL of surface water or per gram of surface solids, groundwater under the influence of these high surface microbial loadings had substantially fewer bacteria (3- to 7-log10 reduction). Among 80 isolates of E. coli tested, 34 (42.5%) were resistant to one or more antibiotics and 22 (27.5%) were multi-antibiotic resistant (resistant to ≥3 antibiotics), with resistance to tetracycline, cefoxitin, amoxicillin/clavulanic acid, and ampicillin being the most common. E. coli isolates from the calf hutch area exhibited the highest levels of multi-antibiotic resistance, much higher than isolates in surface soil solids from heifer and cow pens, flush alleys, manure storage lagoons, and irrigated fields. Among E. coli isolates from four groundwater samples, only one sample exhibited resistance to ceftriaxone, chloramphenicol, and tetracycline, indicating the potential of groundwater contamination with antibiotic-resistant bacteria from dairy operations.


Assuntos
Indústria de Laticínios , Farmacorresistência Bacteriana/genética , Monitoramento Ambiental , Escherichia coli/genética , Água Subterrânea/microbiologia , Animais , California , Bovinos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/isolamento & purificação , Água Subterrânea/química , Testes de Sensibilidade Microbiana , Microbiologia da Água
13.
Cancer Res ; 72(23): 6209-16, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23041547

RESUMO

Toll-like receptors (TLR) are expressed by a variety of cancers, including melanoma, but their functional contributions in cancer cells are uncertain. To approach this question, we evaluated the effects of stimulating or inhibiting the TLR/IL-1 receptor-associated kinases IRAK-1 and IRAK-4 in melanoma cells where their functions are largely unexplored. TLRs and TLR-related proteins were variably expressed in melanoma cell lines, with 42% expressing activated phospho-IRAK-1 constitutively and 85% expressing high levels of phospho-IRAK-4 in the absence of TLR stimulation. Immunohistochemical evaluation of melanoma tumor biopsies (n = 242) revealed two distinct patient populations, one that expressed p-IRAK-4 levels similar to normal skin (55%) and one with significantly higher levels than normal skin (45%). Levels of p-IRAK-4 levels did not correlate with clinical stage, gender, or age, but attenuated IRAK-1,-4 signaling with pharmacologic inhibitors or siRNA-enhanced cell death in vitro in combination with vinblastine. Moreover, in a xenograft mouse model of melanoma, the combined pharmacologic treatment delayed tumor growth and prolonged survival compared with subjects receiving single agent therapy. We propose p-IRAK-4 as a novel inflammation and prosurvival marker in melanoma with the potential to serve as a therapeutic target to enhance chemotherapeutic responses.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Quinases Associadas a Receptores de Interleucina-1/antagonistas & inibidores , Melanoma/tratamento farmacológico , Melanoma/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Animais , Apoptose/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Citocinas/biossíntese , Modelos Animais de Doenças , Ativação Enzimática , Feminino , Perfilação da Expressão Gênica , Humanos , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Masculino , Melanoma/patologia , Camundongos , Camundongos Endogâmicos NOD , Fosforilação , Transdução de Sinais , Receptores Toll-Like/biossíntese , Receptores Toll-Like/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 9): o2528, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22059063

RESUMO

There are two independent 3,5-dimethyl-pyrazole and two independent 2-hy-droxy-5-(phenyl-diazen-yl)benzoic acid mol-ecules [in which intra-molecular O-H⋯O bonds form S(6) graph-set motifs] in the asymmetric unit of the title compound, C(5)H(8)N(2)·C(13)H(10)N(2)O(3). In the crystal, the components are linked by inter-molecular O-H⋯O, O-H⋯N and N-H⋯O hydrogen bonds, forming four-component clusters. Further stabilization is provided by weak C-H⋯π inter-actions.

15.
J Clin Invest ; 121(12): 4810-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22080867

RESUMO

Erythropoiesis, the production of red blood cells, must be tightly controlled to ensure adequate oxygen delivery to tissues without causing thrombosis or stroke. Control of physiologic and pathologic erythropoiesis is dependent predominantly on erythropoietin (EPO), the expression of which is regulated by hypoxia-inducible factor (HIF) activity in response to low oxygen tension. Accumulating evidence indicates that oxygen-independent mediators, including inflammatory stimuli, cytokines, and growth factors, also upregulate HIF activity, but it is unclear whether these signals also result in EPO production and erythropoiesis in vivo. Here, we found that signaling through herpesvirus entry mediator (HVEM), a molecule of the TNF receptor superfamily, promoted HIF-1α activity in the kidney and subsequently facilitated renal Epo production and erythropoiesis in vivo under normoxic conditions. This Epo upregulation was mediated by increased production of NO by renal macrophages. Hvem-deficient mice displayed impaired Epo expression and aggravated anemia in response to erythropoietic stress. These data reveal that HVEM signaling functions to promote HIF-1α activity and Epo production, and thus to regulate erythropoiesis. Furthermore, our findings suggest that this molecular mechanism could represent a therapeutic target for Epo-responsive diseases, including anemia.


Assuntos
Eritropoese/fisiologia , Eritropoetina/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Rim/metabolismo , Membro 14 de Receptores do Fator de Necrose Tumoral/fisiologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Hipóxia Celular , Eritropoetina/genética , Feminino , Perfilação da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/fisiologia , Oxigênio/fisiologia , Quimera por Radiação , Membro 14 de Receptores do Fator de Necrose Tumoral/agonistas , Membro 14 de Receptores do Fator de Necrose Tumoral/deficiência , Membro 14 de Receptores do Fator de Necrose Tumoral/genética , Membro 14 de Receptores do Fator de Necrose Tumoral/imunologia , Transdução de Sinais/fisiologia
16.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): o2730, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22064997

RESUMO

In the title salt, C(15)H(17)N(4)O(4)S(2) (+)·Cl(-), the chloride anion is disordered over two positions with occupancies of 0.776 (6) and 0.224 (6). The cation adopts an L shape and the dihedral angle between the benzene rings is 82.5 (3)°. In the crystal, inversion dimers of cations linked by pairs of N-H⋯N hydrogen bonds occur, with the bond arising from the protonated N atom. The cationic dimers are linked into chains via the disordered chloride ions by way of N-H⋯Cl hydrogen bonds and N-H⋯O, C-H⋯O and C-H⋯Cl inter-actions also occur, which help to consolidate the three-dimensional network.

17.
Zhonghua Nan Ke Xue ; 17(7): 586-90, 2011 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-21823338

RESUMO

OBJECTIVE: To establish an animal model of chronic nonbacterial prostatitis (CNP) using different doses of purified prostate protein with Freund's complete adjuvant (FCA), and to investigate the relationship of the doses with the success of the model construction. METHODS: Thirty male Wistar rats were divided into a control (A) and 4 experimental groups (B, C, D and E) of equal number. The latter 4 groups were given multi-loci intracutaneous injection of 1.0 ml of a 1:1 mixture of purified prostate protein at 20, 40, 60 and 80 mg/ml with Freund's complete adjuvant (FCA), and meanwhile intraperitoneally injected with 0.5 ml of pertussis-diphtheria-tetanus vaccine at 0 and 30 days. On the 45th day, the rats were sacrificed for observation of the pathomorphological changes in the prostate glands with the naked eyes and microscope. RESULTS: Different degrees of chronic inflammation were observed with different degrees of lymphocyte infiltration and interstitial hyperplasia in the experimental rats. More obvious changes were found in Groups C and D than in A, and even more significant in Group E (P < 0.05). CONCLUSION: The rat model of CNP can be successfully established by multi-loci intracutaneous injection of 1.0 ml of a 1: 1 mixture of purified prostate protein at 40 - 60 mg/ml with FCA, and simultaneously intraperitoneal injection of 0.5 ml of pertussis-diphtheria-tetanus vaccine twice within 30 days.


Assuntos
Autoimunidade , Modelos Animais de Doenças , Prostatite , Animais , Relação Dose-Resposta Imunológica , Adjuvante de Freund/farmacologia , Masculino , Ratos , Ratos Wistar
18.
Blood ; 117(8): 2506-14, 2011 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-21220749

RESUMO

B and T lymphocyte attenuator (BTLA) is a co-inhibitory receptor that interacts with herpesvirus entry mediator (HVEM), and this interaction regulates pathogenesis in various immunologic diseases. In graft-versus-host disease (GVHD), BTLA unexpectedly mediates positive effects on donor T-cell survival, whereas immunologic mechanisms of this function have yet to be explored. In this study, we elucidated a role of BTLA in GVHD by applying the newly established agonistic anti-BTLA monoclonal antibody that stimulates BTLA signal without antagonizing BTLA-HVEM interaction. Our results revealed that provision of BTLA signal inhibited donor antihost T-cell responses and ameliorated GVHD with a successful engraftment of donor hematopoietic cells. These effects were dependent on BTLA signal into donor T cells but neither donor non-T cells nor recipient cells. On the other hand, expression of BTLA mutant lacking an intracellular signaling domain restored impaired survival of BTLA-deficient T cells, suggesting that BTLA also serves as a ligand that delivers HVEM prosurvival signal in donor T cells. Collectively, current study elucidated dichotomous functions of BTLA in GVHD to serve as a costimulatory ligand of HVEM and to transmit inhibitory signal as a receptor.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Receptores Imunológicos/metabolismo , Membro 14 de Receptores do Fator de Necrose Tumoral/metabolismo , Transdução de Sinais/imunologia , Animais , Anticorpos Monoclonais/farmacologia , Sobrevivência Celular , Camundongos , Ligação Proteica/imunologia , Receptores Imunológicos/imunologia , Membro 14 de Receptores do Fator de Necrose Tumoral/imunologia , Linfócitos T/imunologia
19.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 11): o2943, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22219972

RESUMO

In the title compound, C(15)H(12)N(4)·H(2)O, the organic mol-ecule displays approximate non-crystallographic twofold symmetry: the dihedral angle between the benzimidazole ring systems is 81.37 (12)°. In the crystal, the components are linked by O-H⋯N hydrogen bonds, forming chains propagating in [101]. Aromatic π-π stacking [centroid-centroid separation = 3.595 (2) Å] helps to consolidate the structure.

20.
Blood ; 116(8): 1291-8, 2010 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-20472828

RESUMO

T-cell tolerance is the central program that prevents harmful immune responses against self-antigens, in which inhibitory PD-1 signal given by B7-H1 interaction plays an important role. Recent studies demonstrated that B7-H1 binds CD80 besides PD-1, and B7-H1/CD80 interaction also delivers inhibitory signals in T cells. However, a role of B7-H1/CD80 signals in regulation of T-cell tolerance has yet to be explored. We report here that attenuation of B7-H1/CD80 signals by treatment with anti-B7-H1 monoclonal antibody, which specifically blocks B7-H1/CD80 but not B7-H1/PD-1, enhanced T-cell expansion and prevented T-cell anergy induction. In addition, B7-H1/CD80 blockade restored Ag responsiveness in the previously anergized T cells. Experiments using B7-H1 or CD80-deficient T cells indicated that an inhibitory signal through CD80, but not B7-H1, on T cells is responsible in part for these effects. Consistently, CD80 expression was detected on anergic T cells and further up-regulated when they were re-exposed to the antigen (Ag). Finally, blockade of B7-H1/CD80 interaction prevented oral tolerance induction and restored T-cell responsiveness to Ag previously tolerized by oral administration. Taken together, our findings demonstrate that the B7-H1/CD80 pathway is a crucial regulator in the induction and maintenance of T-cell tolerance.


Assuntos
Autoantígenos/imunologia , Antígeno B7-1/fisiologia , Tolerância Imunológica/imunologia , Glicoproteínas de Membrana/fisiologia , Peptídeos/fisiologia , Linfócitos T/imunologia , Animais , Antígenos de Diferenciação/fisiologia , Antígeno B7-H1 , Western Blotting , Proliferação de Células , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Imunização , Imunoglobulina G/administração & dosagem , Imunoglobulina G/imunologia , Imunoglobulina G/farmacologia , Imunoprecipitação , Glicoproteínas de Membrana/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Ovalbumina/metabolismo , Fragmentos de Peptídeos/imunologia , Peptídeos/antagonistas & inibidores , Receptor de Morte Celular Programada 1 , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos Lew , Receptores de Antígenos de Linfócitos T/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/citologia , Linfócitos T/metabolismo , Linfócitos T Citotóxicos/imunologia
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