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1.
Small ; : e2402946, 2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38881253

RESUMEN

Oil-water separation based on superwettable materials offers a promising way for the treatment of oil-water mixtures and emulsions. Nevertheless, such separation techniques often require complex devices and external energy input. Therefore, it remains a great challenge to separate oil-water mixtures and emulsions through an energy-efficient, economical, and sustainable way. Here, a novel approach demonstrating the successful separation of oil-water emulsions using antigravity-driven autonomous superwettable pumps is presented. By transitioning from traditional gravity-driven to antigravity-driven separation, the study showcases the unprecedented success in purifying oil/water from emulsions by capillary/siphon-driven superwettable autonomous pumps. These pumps, composed of self-organized interconnected channels formed by the packing of superhydrophobic and superhydrophilic sand particles, exhibit outstanding separation flux, efficiency, and recyclability. The findings of this study not only open up a new avenue for oil-water emulsion separation but also hold promise for profound impacts in the field.

2.
Adv Colloid Interface Sci ; 327: 103159, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38640843

RESUMEN

Dynamic covalent chemistry, which leverages the dynamic nature of reversible covalent bonds controlled by the conditions of reaction equilibrium, has demonstrated great potential in diverse applications related to both the stability of covalent bonds and the possibility of exchanging building blocks, imparting to the systems the possibility of "error checking" and "proof-reading". By incorporating dynamic covalent bonds into surfactant molecular architectures, combinatorial libraries of surfactants with bespoke functionalities can be readily fabricated through a facile strategy, with minimum effort in organic synthesis. Consequently, a multidisciplinary field of research involving the creation and application of dynamic covalent surfactants has recently emerged, which has aroused great attention in surfactant and colloid science, supramolecular chemistry, self-assembly, smart materials, drug delivery, and nanotechnology. This review reports results in this field published over recent years, discusses the possibilities presented by dynamic covalent surfactants and their applications in developing smart self-assembled materials, and outlines some future perspectives.

3.
ChemSusChem ; 16(2): e202201932, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36398691

RESUMEN

Oil pollution results from daily activities and a variety of industries have caused not only severe environmental problems but also wastage of valuable petrochemical resources. Separation based on superwettable materials holds promise; however, practical applications of a single type of superwettable materials were often limited due to their ability in treatment of complicated oil-water systems. Herein, a Gemini-type separator was created through the cooperation of two kinds of superwettable sand particles with opposite wettability, i. e., one is superhydrophobic whereas the other is superhydrophilic. Cooperatively by the two types of superwettable sand, consecutive separation and purification of both water and oil phases from complicated oil-water systems (e. g., water mixed with a lighter or denser oil, water emulsified in oil, oil emulsified in water, and/or a combination of them in one batch) could be achieved with high flux and superior efficiency just in one single operation unit.


Asunto(s)
Purificación del Agua , Agua , Interacciones Hidrofóbicas e Hidrofílicas , Agua/química , Emulsiones/química , Arena , Humectabilidad , Purificación del Agua/métodos
4.
Technol Health Care ; 30(S1): 451-457, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35124619

RESUMEN

BACKGROUND: Targeted therapy using anti-TNF (tumor necrosis factor) is the first option for patients with rheumatoid arthritis (RA). Anti-TNF therapy, however, does not lead to meaningful clinical improvement in many RA patients. To predict which patients will not benefit from anti-TNF therapy, clinical tests should be performed prior to treatment beginning. OBJECTIVE: Although various efforts have been made to identify biomarkers and pathways that may be helpful to predict the response to anti-TNF treatment, gaps remain in clinical use due to the low predictive power of the selected biomarkers. METHODS: In this paper, we used a network-based computational method to identify the select the predictive biomarkers to guide the treatment of RA patients. RESULTS: We select 69 genes from peripheral blood expression data from 46 subjects using a sparse network-based method. The result shows that the selected 69 genes might influence biological processes and molecular functions related to the treatment. CONCLUSIONS: Our approach advances the predictive power of anti-TNF therapy response and provides new genetic markers and pathways that may influence the treatment.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Antirreumáticos/farmacología , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/genética , Biomarcadores/metabolismo , Expresión Génica , Humanos , Resultado del Tratamiento , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico , Factor de Necrosis Tumoral alfa/genética
5.
Allergol Immunopathol (Madr) ; 49(5): 16-24, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34476917

RESUMEN

OBJECTIVES: This study aimed to evaluate the efficacy of air purifier therapy for patients with allergic asthma. METHODS: Thirty-eight subjects were categorized under two groups namely treatment group and control group. All subjects were under 18 years of age and they had been clinically diagnosed with allergic asthma. The treatment group used high efficiency particulate air (HEPA) purifiers for six consecutive months, and the control group did not use the air filters. Particulate matter (PM) data and dust samples (from bedding and a static point) were collected from the subjects' bedrooms before they started using the air purifiers and each month thereafter. Simultaneously, the subjects were asked to complete a questionnaire for the Asthma Control Test (ACT) or Childhood Asthma Control Test (C-ACT). Fractional exhaled nitric oxide (FENO) tests were performed at the start and end of the study. The concentrations of Der p1 and Der f1 were measured in the dust samples. RESULTS: (1) After utilizing the air purifier, the concentrations of house dust mite (HDM) allergens (Der p1+ Der f1) in the dust samples decreased. In addition, the PMindoor/outdoor values significantly decreased. (2) The ACT and C-ACT scores in the treatment group maintained a steady significant upward trend. (3) At the end of the study, the FENO levels in both groups were lower, although the differences were not significant. CONCLUSIONS: It is witnessed that HEPA air purifiers can decrease indoor HDM allergen and PM levels and improve the quality of life for allergic asthma patients.


Asunto(s)
Filtros de Aire , Contaminación del Aire Interior , Asma , Adolescente , Contaminación del Aire Interior/análisis , Alérgenos , Antígenos Dermatofagoides , Asma/terapia , Niño , Polvo , Prueba de Óxido Nítrico Exhalado Fraccionado , Humanos , Material Particulado , Calidad de Vida
6.
Plants (Basel) ; 10(8)2021 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-34451726

RESUMEN

Gene silencing is the epigenetic regulation of any gene in order to prevent gene expression at the transcription or translation levels. Among various gene silencing techniques, RNA silencing (RNAi) is notable gene regulation technique that involves sequence-specific targeting and RNA degradation. However, the effectiveness of transgene-induced RNAi in F1 generation of chrysanthemum has not been studied yet. In the current study, we used RNAi-constructed CmTFL1 (white-flowered) and CmSVP overexpressed (yellow flowered) transgenic plants of previously conducted two studies for our experiment. Cross hybridization was performed between these intergeneric transgenic and non-transgenic plants of the winter-growing chrysanthemum selection "37" (light pink flowered). The transgene CmSVP was confirmed in F1 hybrids by RT-PCR analysis, whereas hybrids of CmTFL1 parental plants were non-transgenic. Besides this, quantitative real-time PCR (qPCR) was used to explain the molecular mechanism of flower development using reference genes. Intergeneric and interspecific hybrids produced different colored flowers unlike their respective parents. These results suggest that generic traits of CmSVP overexpressed plants can be transferred into F1 generations when crossed with mutant plants. This study will aid in understanding the breeding phenomenon among intergeneric hybrids of chrysanthemum plants at an in vivo level, and such transgenics will also be more suitable for sustainable flower yield under a low-light production system.

7.
Pharmacol Res ; 159: 104932, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32473309

RESUMEN

Precision oncology involves effectively selecting drugs for cancer patients and planning an effective treatment regimen. However, for Molecular targeted drug, using genomic state of the drug target to select drugs has limitations. Many patients who could benefit from molecularly targeted drugs, but they are being missed due to the insufficient labelling ability of the existing target genes. For non-specific chemotherapy drugs, most of the first-line anticancer drugs do not have biomarkers to guide doctor make treatment regimen. Furthermore, it is important to determine a long-term treatment plan based on the patient's genomic data during tumor evolution. Therefore, it is necessary to establish a tumor drug sensitivity prediction model, which can assist doctors in designing a personalized tumor treatment regimen. This paper proposed a novel model to predict tumor drug sensitivity including targeted drugs and non-specific chemotherapy drugs. This model uses statistical methods based on Bimodal distribution to select multimodal genetic data to solve dimensional challenges and reduce noise and to establish a classification model to predict the effectiveness of the drug in the tumor cell line using machine learning. The experimental test 87 molecular targeted drugs and non-specific chemotherapy drugs. The results show that the method can effectively predict the sensitivity of tumor drugs with an average sensitivity of 0.98 and specificity of 0.97. This model is worth to promotion. If it can be successfully used in clinical trials, it will effectively assist doctors to develop personalized cancer treatment programs and expand the application of molecularly targeted drugs.


Asunto(s)
Antineoplásicos/farmacología , Biomarcadores de Tumor/antagonistas & inhibidores , Técnicas de Apoyo para la Decisión , Genómica , Aprendizaje Automático , Neoplasias/tratamiento farmacológico , Medicina de Precisión , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Toma de Decisiones Clínicas , Bases de Datos Genéticas , Ensayos de Selección de Medicamentos Antitumorales , Regulación Neoplásica de la Expresión Génica , Humanos , Modelos Estadísticos , Terapia Molecular Dirigida , Neoplasias/genética , Neoplasias/metabolismo , Farmacogenética , Transducción de Señal
8.
PLoS One ; 14(10): e0222702, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31600235

RESUMEN

Slope one is a popular recommendation algorithm due to its simplicity and high efficiency for sparse data. However, it often suffers from under-fitting since the global information of all relevant users/items are considered. In this paper, we propose a new scheme called enhanced slope one recommendation through local information embedding. First, we employ clustering algorithms to obtain the user clusters as well as item clusters to represent local information. Second, we predict ratings using the local information of users and items in the same cluster. The local information can detect strong localized associations shared within clusters. Third, we design different fusion approaches based on the local information embedding. In this way, both under-fitting and over-fitting problems are alleviated. Experiment results on the real datasets show that our approaches defeats slope one in terms of both mean absolute error and root mean square error.


Asunto(s)
Análisis por Conglomerados , Interpretación Estadística de Datos , Matemática , Algoritmos , Hábitos , Humanos , Modelos Lineales , Proyectos de Investigación
10.
PLoS One ; 12(8): e0183570, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28817692

RESUMEN

This paper proposes a new measure for recommendation through integrating Triangle and Jaccard similarities. The Triangle similarity considers both the length and the angle of rating vectors between them, while the Jaccard similarity considers non co-rating users. We compare the new similarity measure with eight state-of-the-art ones on four popular datasets under the leave-one-out scenario. Results show that the new measure outperforms all the counterparts in terms of the mean absolute error and the root mean square error.


Asunto(s)
Algoritmos , Modelos Teóricos
11.
Chin J Integr Med ; 2016 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-27358202

RESUMEN

OBJECTIVE: To investigate whether Chinese medicine (CM) recipes could ameliorate H5N1 influenza virus infection in BALB/c mice model. METHODS: BALB/c mice were orally administrated with 5 CM recipes (removing toxin, tonifying qi, cooling blood, laxation, and compound recipes), oseltamivir, or saline solution respectively for 5 consecutive days after the infection of H5N1 influenza virus. Series of indices were employed to evaluate the amelioration of the 5 CM recipes on infection, including clinical assessment, gross observation, histopathologic findings, cytokine levels and viral burden in the lungs. RESULTS: Two CM recipes (cooling blood and compound recipes) could postpone the death period of the mice infected with high-dose H5N1 influenza virus (P< 0.05). And for the mice infected with low-dose H5N1 influenza virus, CM recipes could significantly reduce the mortality and inhibit viral proliferation in the lungs as compared with the control group (P<0.05). There was no significant difference in lung coefficients between the treatment and the control groups, but histopathological findings in the lungs were improved in CM recipes groups compared to control group findings. A transient increase was observed in pro-inflammatory and anti-inflammatory cytokines during the first 6 days of infection. The levels of interleukin (IL)-12p40 and interferon-gamma of the treatment groups were significantly lower than that of the control group at day 3 post-infection (P<0.05), while only compound recipe were significantly lower in level of tumor necrosis factor alpha than the control (P<0.05). The level of IL-10 of the control was higher than others, and the differences between the control and cooling blood, removing toxin recipes were significant (P<0.05). CONCLUSIONS: Results of this study suggested the potentials of the CM recipes in ameliorating influenza virus infection by suppressing viral proliferations, improving histopathological lesions, and inhibition of over expression of inflammatory cytokines.

12.
Cell Physiol Biochem ; 37(6): 2209-20, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26610246

RESUMEN

BACKGROUND/AIMS: Long non-coding RNAs (lncRNAs) play important roles in diverse biological processes, such as cell growth, apoptosis and migration. Although downregulation of lncRNA maternally expressed gene 3 (MEG3) has been identified in several cancers, little is known about its role in prostate cancer progression. The aim of this study was to detect MEG3 expression in clinical prostate cancer tissues, investigate its biological functions in the development of prostate cancer and the underlying mechanism. METHODS: MEG3 expression levels were detected by qRT-PCR in both tumor tissues and adjacent non-tumor tissues from 21 prostate cancer patients. The effects of MEG3 on PC3 and DU145 cells were assessed by MTT assay, colony formation assay, western blot and flow cytometry. Transfected PC3 cells were transplanted into nude mice, and the tumor growth curves were determined. RESULTS: MEG3 decreased significantly in prostate cancer tissues relative to adjacent normal tissues. MEG3 inhibited intrinsic cell survival pathway in vitro and in vivo by reducing the protein expression of Bcl-2, enhancing Bax and activating caspase 3. We further demonstrated that MEG3 inhibited the expression of cell cycle regulatory protein Cyclin D1 and induced cell cycle arrest in G0/G1 phase. CONCLUSIONS: Our study presents an important role of MEG3 in the molecular etiology of prostate cancer and implicates the potential application of MEG3 in prostate cancer therapy.


Asunto(s)
Apoptosis/genética , Proliferación Celular/genética , Neoplasias de la Próstata/patología , ARN Largo no Codificante/fisiología , Animales , Caspasa 3/metabolismo , Ciclina D1/metabolismo , Activación Enzimática , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Desnudos , Neoplasias de la Próstata/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo
13.
Inorg Chem ; 54(9): 4337-44, 2015 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-25906391

RESUMEN

The synthesis, structural characterization, and magnetic properties of four related heterometallic complexes with formulas [Dy(III)2Co(II)(C7H5O2)8]·6H2O (1), [Dy(III)2Ni(II)(C7H5O2)8]·(C7H6O2)2 (2), Tb(III)2Co(II)(C7H5O2)8 (3), and Dy(III)2Cd(II)(C7H5O2)8 (4) were reported. Each of complexes has a perfectly linear arrangement of the metal ions with two terminal Ln(III) (Ln(III) = Dy(III), Tb(III)) ions and one central M(II) (M(II) = Co(II), Ni(II), Cd(II)) ion. It was found that 1-3 displayed obvious magnetic interactions between the spin carriers according to the direct current (dc) susceptibility measurements. Alternating current (ac) magnetic susceptibility measurements indicate that complexes 1-4 all exhibit single-molecule magnet (SMM) behavior, while the replacement of the diamagnetic Cd(II) by paramagnetic ions leads to a significant slowing of the relaxation thanks to the magnetic interactions between 3d and 4f ions, resulting in higher relaxation barrier for complexes 1 and 2. Moreover, both Dy2Co and Dy2Ni compounds exhibit dual relaxation pathways that may originate from the single ion behavior of individual Dy(III) ions and the coupling between Dy(III) and Co(II)/Ni(II) ions, respectively, which can be taken as the feature of 3d-4f SMMs. The Ueff for 1 of 127 K is a relatively high value among the reported 3d-4f SMMs. The results demonstrate that the magnetic coupling between 3d and 4f ions is crucial to optimize SMM parameters. The synthetic approach illustrated in this work represents an efficient route to design nd-4f based SMMs via incorporating suitable paramagnetic 3d and even 4d and 5d ions into the d-f system.

14.
APMIS ; 123(5): 410-21, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25912129

RESUMEN

High density lipoprotein (HDL) dysfunction has been widely reported in clinic, and oxidation of HDL (ox-HDL) was shown to be one of the most common modifications in vivo and participate in the progression of atherosclerosis. But the behind mechanisms are still elusive. In this study, we firstly analyzed and found strong relationship between serum ox-HDL levels and risk factors of coronary artery diseases in clinic, then the effects of ox-HDL in initiation and progression of atherosclerosis in LDLR knockout mice were investigated by infusion of ox-HDL dissolved in chitosan hydrogel before the formation of lesions in vivo. Several new evidence were shown: (i) the serum levels of ox-HDL peaked early before the formation of lesions in LDLR mice fed with high fat diet similar to oxidative low density lipoprotein, (ii) the formation of atherosclerotic lesions could be accelerated by infusion of ox-HDL, (iii) the pro-atherosclerotic effects of ox-HDL were accompanied by imbalanced levels of effector and regulatory T cells and relative gene expressions, which implied that imbalance of teff and treg might contribute to the pro-atherosclerosis effects of ox-HDL.


Asunto(s)
Aterosclerosis/sangre , Aterosclerosis/inmunología , Lipoproteínas HDL/sangre , Receptores de LDL/deficiencia , Subgrupos de Linfocitos T/inmunología , Linfocitos T Reguladores/inmunología , Animales , Aorta/patología , Aterosclerosis/etiología , Estudios de Casos y Controles , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/etiología , Enfermedad de la Arteria Coronaria/inmunología , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Humanos , Lipoproteínas HDL/administración & dosificación , Lipoproteínas HDL/química , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Oxidación-Reducción , Receptores de LDL/genética
15.
Sheng Li Xue Bao ; 67(2): 181-5, 2015 Apr 25.
Artículo en Chino | MEDLINE | ID: mdl-25896048

RESUMEN

Using intracellular potential recording technique in vivo, a series of hyperpolarizing and depolarizing currents at different intensities with a 50-ms duration were injected to somatic nociceptive neurons (SNNs) and somatic non-nociceptive neurons (SNNNs) in the anterior cingulate gyrus (ACG) of cats. The membrane electrical responses of the neurons were recorded, and the membrane electrical parameters of the neurons were calculated for comparative study on membrane electrical properties of SNNs and SNNNs of the ACG. A total of 188 ACG neurons from 57 cats were recorded. Among the 188 neurons, 172 (91.5%) and 16 (8.5%) were SNNs and SNNNs, respectively. The I-V curves of SNNs and SNNNs in the ACG were "S" shapes. When the absolute value of injected current intensity was less than or equal to 1 nA (≤ 1 nA), the I and V of I-V curves of both SNNs and SNNNs were linearly correlated (rSNNs = 0.99, rSNNNs = 0.99). When the absolute value of injected current intensity was more than 1 nA, both SNNs and SNNNs showed a certain inward or outward rectification behavior. Compared with SNNNs, SNNs had stronger rectification and lower adaptability (P < 0.01). With the increase of injected current intensity, the changes of frequency of discharges of SNNs were higher than those of SNNNs. In addition, the membrane resistance (Rm), the membrane capacity (Cm) and the time constant (τ) of SNNs were larger than those of SNNNs (P < 0.05 or P < 0.01). The differences in the membrane electrical properties between SNNs and SNNNs in the ACG suggested the disparity in neuronal cell size and cell membrane structure between them. The results of this study provided the experimental basis for deeply elucidating the mechanisms of somatic nociceptive sensation and characteristics on the membrane electrical aspects of ACG neurons.


Asunto(s)
Giro del Cíngulo/citología , Potenciales de la Membrana , Neuronas/fisiología , Nociceptores/fisiología , Animales , Gatos
16.
Dalton Trans ; 44(7): 3430-8, 2015 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-25601415

RESUMEN

The reaction of Mn(OAc)2·4H2O and Ln(NO3)3·6H2O with N-(2-aminopropyl)-2-hydroxybenzamide and salicylic aldehyde in methanol/methylene dichloride produces yellow crystals of Ln2Mn(C7H5O2)8 (Ln = Gd (), Tb (), Dy (), Ho () and Er ()), in the presence of triethylamine. Three metal ions are connected by six µ2-phenolate oxygen atoms of six salicylic aldehyde ligands, resulting in perfect linear [Ln(III)-Mn(II)-Ln(III)] structures. Magnetic studies of these complexes have been performed and AC susceptibility measurements show the presence of a temperature-dependent out-of-phase ac signal for complexes and indicating single-molecule magnet (SMM) behavior. The Dy(III)2Mn(II) compound shows double relaxation pathways which may originate from the single ion behavior of individual Dy(III) ions and the weak coupling between Dy(III) and Mn(II) ions, respectively. The Ueff of 92.4(2) K is a relatively high value among 3d-4f SMMs. Moreover, complexes and represent the first linear Mn-Ln SMMs containing only divalent manganese ions as far as we know. The result suggests the positive effects of magnetic coupling to enhance their SMM behavior, presenting a promising strategy for constructing efficient heterometallic SMMs.

17.
ScientificWorldJournal ; 2014: 649596, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25180204

RESUMEN

Aggregated recommendation refers to the process of suggesting one kind of items to a group of users. Compared to user-oriented or item-oriented approaches, it is more general and, therefore, more appropriate for cold-start recommendation. In this paper, we propose a random forest approach to create aggregated recommender systems. The approach is used to predict the rating of a group of users to a kind of items. In the preprocessing stage, we merge user, item, and rating information to construct an aggregated decision table, where rating information serves as the decision attribute. We also model the data conversion process corresponding to the new user, new item, and both new problems. In the training stage, a forest is built for the aggregated training set, where each leaf is assigned a distribution of discrete rating. In the testing stage, we present four predicting approaches to compute evaluation values based on the distribution of each tree. Experiments results on the well-known MovieLens dataset show that the aggregated approach maintains an acceptable level of accuracy.


Asunto(s)
Conceptos Matemáticos
18.
Small ; 10(20): 4100-5, 2014 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-24976002

RESUMEN

Treating inflammation with a dual-switch-controlled release system: The release of a drug from the developed microbead system occurs only in response to both an increase in local temperature and an acidic environmental pH. This dual-switch-controlled release system has the advantages of distinguishing between inflamed and healthy tissues to improve treatment efficacy.


Asunto(s)
Sistemas de Liberación de Medicamentos , Concentración de Iones de Hidrógeno , Microesferas , Microscopía Confocal , Microscopía Electrónica de Rastreo
19.
Bing Du Xue Bao ; 30(6): 675-82, 2014 Nov.
Artículo en Chino | MEDLINE | ID: mdl-25868283

RESUMEN

In this study, five rhesus macaques were inoculated intravenously with SIVmac251 to establish a model of simian autoimmune deficiency syndrome (SAIDS). Peripheral blood samples were collected at different time points to monitor changes in the total T cell number and T lymphocyte subset. Plasma viral loads, cytokine expression levels and anti-SIV antibody levels were also assayed to acquire certain basic indexes to evaluate disease progression in the rhesus macaque SAIDS model. During the acute stage of infection, plasma viral loads reached a peak at week 1 post-inoculation and lasted for approximately 3 to 44 weeks. The CD3+ CD4+ T lymphocyte count in peripheral blood also transitorily decreased. During the same period, the level of interferon-gamma show an increasing trend, whereas IL-12 levels decreased; IL-2, IL-4, IL-10 and TNF-alpha were maintained at normal levels or could not be detected. During the asymptomatic and ARC phases, plasma viral loads persisted above 10(4) RNA copies/mL and either increased or declined during the later stages of disease; CD3+ CD4+ counts showed a steadily declining trend and the ratio of CD4 to CD8 decreased during late-stage disease. Moreover, antibodies against viral proteins were detected in the plasma and showed a significant increasing trend, while there were no apparently changes in the levels of IFN-gamma, IL-12, IL-2, IL-4, IL-10 and TNF-alpha. In conclusion, the characteristics of the SIV animal models in our study are similar to those of patients with AIDS. Therefore, the rhesus macaque SIVmac251 infection models can be applied for further studies into AIDS.


Asunto(s)
Modelos Animales de Enfermedad , Infecciones por VIH/virología , VIH-1/fisiología , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/fisiología , Animales , Anticuerpos Antivirales/sangre , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos/virología , Citocinas/genética , Citocinas/inmunología , Infecciones por VIH/genética , Infecciones por VIH/inmunología , Humanos , Masculino , Síndrome de Inmunodeficiencia Adquirida del Simio/genética , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Carga Viral
20.
Biochemistry ; 52(51): 9212-22, 2013 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-24328126

RESUMEN

ß-Sheets are one of the fundamental three-dimensional building blocks for protein structures. Oppositely charged amino acids are frequently observed directly across one another in antiparallel sheet structures, suggesting the importance of cross-strand ion pairing interactions. Despite the apparent electrostatic nature of ion pairing interactions, the charged amino acids Asp, Glu, Arg, Lys have different numbers of hydrophobic methylenes linking the charged functionality to the backbone. Accordingly, the effect of charged amino acid side chain length on cross-strand ion pairing interactions at lateral non-hydrogen bonded positions was investigated in a ß-hairpin motif. The negatively charged residues with a carboxylate (Asp, Glu, Aad in increasing length) were incorporated at position 4, and the positively charged residues with an ammonium (Dap, Dab, Orn, Lys in increasing length) were incorporated at position 9. The fraction folded population and folding free energy were derived from the chemical shift deviation data. Double mutant cycle analysis was used to determine the interaction energy for the potential lateral ion pairs. Only the Asp/Glu-Dap interactions with shorter side chains and the Aad-Orn/Lys interactions with longer side chains exhibited stabilizing energetics, mostly relying on electrostatics and hydrophobics, respectively. This suggested the need for length matching of the interacting residues to stabilize the ß-hairpin motif. A survey of a nonredundant protein structure database revealed that the statistical sheet pair propensity followed the trend Asp-Lys < Glu-Lys, also implying the need for length matching of the oppositely charged residues.


Asunto(s)
Aminoácidos Acídicos/química , Aminoácidos Básicos/química , Lisina/análogos & derivados , Modelos Moleculares , Péptidos/química , Bases de Datos de Proteínas , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Lisina/química , Proteínas Mutantes/química , Resonancia Magnética Nuclear Biomolecular , Oligopéptidos/química , Oligopéptidos/genética , Péptidos/genética , Pliegue de Proteína , Estabilidad Proteica , Estructura Secundaria de Proteína , Desplegamiento Proteico , Electricidad Estática
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