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1.
J Pharm Biomed Anal ; 246: 116164, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38776585

RESUMEN

Evaluating the quality of herbal medicine based on the content and activity of its main components is highly beneficial. Developing an eco-friendly determination method has significant application potential. In this study, we propose a new method to simultaneously predict the total flavonoid content (TFC), xanthine oxidase inhibitory (XO) activity, and antioxidant activity (AA) of Prunus mume using near-infrared spectroscopy (NIR). Using the sodium nitrite-aluminum nitrate-sodium hydroxide colorimetric method, uric acid colorimetric method, and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) free radical scavenging activity as reference methods, we analyzed TFC, XO, and AA in 90 P. mume samples collected from different locations in China. The solid samples were subjected to NIR. By employing spectral preprocessing and optimizing spectral bands, we established a rapid prediction model for TFC, XO, and AA using partial least squares regression (PLS). To improve the model's performance and eliminate irrelevant variables, competitive adaptive reweighted sampling (CARS) was used to calculate the pretreated full spectrum. Evaluation model indicators included the root mean square error of cross-validation (RMSECV) and determination coefficient (R2) values. The TFC, XO, and AA model, combining optimal spectral preprocessing and spectral bands, had RMSECV values of 0.139, 0.117, and 0.121, with RCV2 values exceeding 0.92. The root mean square error of prediction (RMSEP) for the TFC, XO, and AA model on the prediction set was 0.301, 0.213, and 0.149, with determination coefficient (RP2) values of 0.915, 0.933, and 0.926. The results showed a strong correlation between NIR with TFC, XO, and AA in P. mume. Therefore, the established model was effective, suitable for the rapid quantification of TFC, XO, and AA. The prediction method is simple and rapid, and can be extended to the study of medicinal plant content and activity.

2.
Nat Commun ; 15(1): 4416, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789426

RESUMEN

Ferroelectric materials, whose electrical polarization can be switched under external stimuli, have been widely used in sensors, data storage, and energy conversion. Molecular orbital breaking can result in switchable structural and physical bistability in ferroelectric materials as traditional spatial symmetry breaking does. Differently, molecular orbital breaking interprets the phase transition mechanism from the perspective of electronics and sheds new light on manipulating the physical properties of ferroelectrics. Here, we synthesize a pair of organosilicon Schiff base ferroelectric crystals, (R)- and (S)-N-(3,5-di-tert-butylbenzylidene)-1-((triphenylsilyl)oxy)ethanamine, which show optically controlled phase transition accompanying the molecular orbital breaking. The molecular orbital breaking is manifested as the breaking and reformation of covalent bonds during the phase transition process, that is, the conversion between C = N and C-O in the enol form and C-N and C = O in the keto form. This process brings about photo-mediated bistability with multiple physical channels such as dielectric, second-harmonic generation, and ferroelectric polarization. This work further explores this newly developed mechanism of ferroelectric phase transition and highlights the significance of photo-mediated ferroelectric materials for photo-controlled smart devices and bio-sensors.

3.
Chem Commun (Camb) ; 60(32): 4322-4325, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38535993

RESUMEN

Here, we synthesized a series of cholesteryl-based compounds, whose phases and their transformation can be modulated by temperature and the chain length of the fluoroalkyl moieties. To our knowledge, this is the first time that the phase transition could be modulated with perfluoroalkyl tail engineering in organic single-component ferroelectric crystals.

4.
Adv Mater ; 36(8): e2307936, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37907064

RESUMEN

Ferroelectric lithography, which can purposefully control and pattern ferroelectric domains in the micro-/nanometer scale, has extensive applications in data memories, field-effect transistors, race-track memory, tunneling barriers, and integrated biochemical sensors. In pursuit of mechanical flexibility and light weight, organic ferroelectric polymers such as poly(vinylidene fluoride) are developed; however, they still suffer from complicated stretching processes of film fabrication and poor degradability. These poor features severely hinder their applications. Here, the ferroelectric lithography on the biocompatible and biodegradable poly(lactic acid) (PLA) thin films at room temperature is demonstrated. The semicrystalline PLA thin film can be easily fabricated through the melt-casting method, and the desired domain structures can be precisely written according to the predefined patterns. Most importantly, the coercive voltage (Vc ) of PLA thin film is relatively low (lower than 30 V) and can be further reduced with the decrease of the film thickness. These intriguing behaviors combined with satisfying biodegradability make PLA thin film a desirable candidate for ferroelectric lithography and enable its future application in the field of bioelectronics and biomedicine. This work sheds light on further exploration of ferroelectric lithography on other polymer ferroelectrics as well as their application as nanostructured devices.

5.
Nat Commun ; 14(1): 5854, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37730766

RESUMEN

Organic martensitic compounds are an emerging type of smart material with intriguing physical properties including thermosalient effect, ferroelasticity, and shape memory effect. However, due to the high structural symmetry and limited design theories for these materials, the combination of ferroelectricity and martensitic transformation has rarely been found in organic systems. Here, based on the chemical design strategies for molecular ferroelectrics, we show a series of asymmetric 1,4,5,8-naphthalenediimide derivatives with the homochiral amine and 2,2,6,6-tetramethylpiperidine-N-oxyl components, which adopt the low-symmetric polar structure and so allow ferroelectricity. Upon H/F substitution, the fluorinated compounds exhibit reversible ferroelectric and martensitic transitions at 399 K accompanied by a large thermal hysteresis of 132 K. This large thermal hysteresis with two competing (meta)-stable phases is further confirmed by density functional theory calculations. The rare combination of martensitic phase transition and ferroelectricity realizes the bistability with two different ferroelectric phases at room temperature. Our finding provides insight into the exploration of martensitic ferroelectric compounds with potential applications in switchable memory devices, soft robotics, and smart actuators.

6.
Phys Rev Lett ; 130(17): 176802, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37172248

RESUMEN

The mechanism on ferroelectric phase transitions is mainly attributed to the displacive and/or order-disorder transition of internal components since the discovery of the ferroelectricity in 1920, rather than the breaking and recombination of chemical bonds. Here, we demonstrate how to utilize the chemical bond rearrangement in a diarylethene-based crystal to realize the light-driven mm2F1-type ferroelectric phase transition. Such a photoinduced phase transition is entirely driven by switchable covalent bonds with breaking and reformation, enabling the reversible light-controllable ferroelectric polarization switching, dielectric and nonlinear optical bistability. Moreover, light as quantized energy can achieve contactless, nondestructive, and remote-control operations. This work proposes a new mechanism of ferroelectric phase transition, and highlights the significance of photochromic molecules in designing new ferroelectrics for photocontrol data storage and sensing.

7.
Adv Sci (Weinh) ; 9(18): e2201702, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35470590

RESUMEN

Organic ferroelectrics, as a type of crystalline compound, are generally solution processing. However, for most crystalline compounds, the changing of solvent would not influence the crystalline phase, let alone their physical performance. Here, the solvent selective effect occurs in the iodinated adamantanone ferroelectrics. By changing the solvent with different polarities, the ferroelectric crystals can be induced in two different phases, which is unprecedented to the knowledge. More strikingly, this solvent-induced transformation could realize the physical performance optimization in the orthorhombic phase (orth-I-OA, obtained from ethanol) with a stronger second harmonic generation (SHG) response, greater piezoelectric coefficient d33 of 5 pC N-1 , and larger spontaneous polarization (Ps ) of 3.43 µC cm-2 than those of monoclinic one (mono-I-OA, obtained from ethyl acetate). Such an intriguing phenomenon might be closely related to solvent polarity. Based on the quantitative and qualitative analyses, the similar interaction energies of these two phases suggest that their transformation could be easily realized via changing the solvent. This work provides new insights into the chemical design and performance optimization of organic ferroelectrics.

8.
Angew Chem Int Ed Engl ; 61(22): e202200135, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35166001

RESUMEN

Organic ferroelectrics are flexible, lightweight, and bio-friendly, promising for bio-harmonized electronic devices, while their ferroelectric lithography remains relatively unexplored. Here, by introducing homochirality and ZE photoisomerization, we obtained a pair of organic enantiomorphic ferroelectrics, di(benzylamino)-substituted derivatives of muconic acids, the first ferroelectrics in the muconic family. Their ferroelectric and chiral features were confirmed by the polarization-electric field hysteresis loops and circular dichroism spectra, respectively. Piezoresponse force microscopy measurements demonstrate that the desired domain structure can be precisely achieved by applying a local electric field on a predefined pattern in their thin films. Moreover, thermogravimetric analyses reveal that their ferroelectricity can persist up to above 550 K. The precise pattern lithography and excellent thermal stability make them competitive candidates for ferroelectric lithography.

9.
Genes (Basel) ; 11(7)2020 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-32668742

RESUMEN

Alternative splicing (AS) is a post-transcriptional level of gene expression regulation that increases transcriptome and proteome diversity. How the AS landscape of rapeseed (Brassica napus L.) changes in response to the fungal pathogen Sclerotinia sclerotiorum is unknown. Here, we analyzed 18 RNA-seq libraries of mock-inoculated and S. sclerotiorum-inoculated susceptible and tolerant B. napus plants. We found that infection increased AS, with intron retention being the main AS event. To determine the key genes functioning in the AS response, we performed a differential AS (DAS) analysis. We identified 79 DAS genes, including those encoding splicing factors, defense response proteins, crucial transcription factors and enzymes. We generated coexpression networks based on the splicing isoforms, rather than the genes, to explore the genes' diverse functions. Using this weighted gene coexpression network analysis alongside a gene ontology enrichment analysis, we identified 11 modules putatively involved in the pathogen defense response. Within these regulatory modules, six DAS genes (ascorbate peroxidase 1, ser/arg-rich protein 34a, unknown function 1138, nitrilase 2, v-atpase f, and amino acid transporter 1) were considered to encode key isoforms involved in the defense response. This study provides insight into the post-transcriptional response of B. napus to S. sclerotiorum infection.


Asunto(s)
Empalme Alternativo/genética , Ascomicetos/genética , Brassica napus/genética , Interacciones Huésped-Patógeno/genética , Ascomicetos/patogenicidad , Brassica napus/microbiología , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Redes Reguladoras de Genes/genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteoma/genética , Transcriptoma/genética
10.
Shanghai Kou Qiang Yi Xue ; 27(4): 401-406, 2018 Aug.
Artículo en Chino | MEDLINE | ID: mdl-30483709

RESUMEN

PURPOSE: To evaluate the clinical effect of short implants in atrophic posterior region. METHODS: A total of 38 Bicon short implants (≤8 mm) were placed in 30 patients with 3-10 mm of bone height in the posterior region from January to December 2012. The follow-up period was 4 years, radiographic, clinical examination(improved plaque index, improved bleeding index, probing depth)were conducted and patient satisfactions were investigated with Oral Health Impact Profile (OHIP-I). Statistical analysis was performed using SPSS17.0 software package. RESULES: Implant survival rate of short implants was 100% and implant success rate was 94.7%. The mean peri-implant bone resorption value was (0.25±0.65) mm,the change of mesial and distal marginal bone was (-0.23±0.74) mm and (-0.27±0.59) mm, respectively. Crown to implant ratio (C/I)= 1.77±0.34, the implants were divided into 3 groups according to C/I≤1,12,there was no significant difference in marginal bone changes and no correlation between C/I and bone resorption. Through clinical examination,improved plaque index was 1.08±0.88,improved bleeding index was 1.11±0.83 and the average probing depth was (3.08±1.19) mm. OHIP-I score was 2.66±0.88, there was significant difference compared with preoperative OHIP-I score. CONCLUSIONS: Short implants are feasible and the success rate is high in the posterior region with insufficient bone height. The soft tissue around the short implants is in good health.While avoiding complex surgical procedures, reducing trauma, shortening the duration of treatment,short implants have a high degree of acceptance and the patient satisfactions are excellent.At the same time, regular preventive maintenance is important to maintain the long-term stability of implant dentures.


Asunto(s)
Coronas , Implantación Dental , Implantes Dentales , Prótesis Dental de Soporte Implantado , Pérdida de Hueso Alveolar , Implantación Dental Endoósea , Diseño de Prótesis Dental , Estudios de Seguimiento , Humanos , Resultado del Tratamiento
11.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 33(4): 342-345, 2017 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-29926640

RESUMEN

OBJECTIVE: To observe the abnormality of the electrocardiogram (ECG) and the characteristics of arrhythmia in the early stage of older pregnant women and to record the late outcome of atrial and ventricular arrhythmia. METHODS: Two hundrend and ninty pregnant women were divided into 3 groups by age under 35 group, 35~39 group and 40~45 group. The ECG waveform was analyzed systematically when the patients were subjected to routine ECG examination and abnormal changes of ECG were collected and recorded, including ST segment changes, various arrhythmias, etc. Then the recovery and deterioration rate of atrial, ventricular arrhythmia was recorded. RESULTS: The incidence of arrhythmia in 35~39 group and 40~45 group was significantly higher than under 35 group (P<0.05); the incidence of abnormal ST section in 35~39 group and 40~45 group was significantly higher than under 35 group(P<0.05); and the incidence of widened QRS wave in 40~45 group was higher than under 35 group (P<0.05). The incidence of sinus tachycardia, sinus irregularityand atrial premature beats in 35~39 group and 40~45 group was obviously lower than that under 35 group (P<0.05); the incidence of Paroxysmal supraventricular tachycardia in 40~45 group was obviously higher than under 35 group (P<0.05) and the incidence of ventricular premature beat and atrial fibrillation in 35~39 group and 40~45 group was significantly higher than under 35 group (P<0.05). The recovery rate of atrial arrhythmia in 40~45 group was obviously lower than under 35 group (P<0.05);the exacerbation rate of trial and ventricular arrhythmia in 40~45 group was obviously higher than over 35 group (P<0.05). The incidences of IUGR in 35~39 group and 40~45 group with abnormal ECG was obviously higher than under 35 group and 35~39 group with normal ECG; The incidences of fetal distress in 35~39 year-old group and 40~45 year-old group with abnormal ECG was obviously higher than under 35 group(P<0.05). CONCLUSIONS: There is a positive correlation between the old age and the incidence of arrhythmia in the early stage of pregnancy, and old age factors can reduce the recovery rate but increase the incidence of deterioration of arrhythmia. And older pregnant women with abnormal ECG have undesirable effect to perinatal infant.


Asunto(s)
Factores de Edad , Arritmias Cardíacas/diagnóstico , Electrocardiografía , Complicaciones Cardiovasculares del Embarazo/diagnóstico , Adulto , Fibrilación Atrial/diagnóstico , Femenino , Atrios Cardíacos , Humanos , Incidencia , Persona de Mediana Edad , Embarazo
12.
Asian Pac J Trop Med ; 8(11): 923-929, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26614992

RESUMEN

OBJECTIVE: To investigate the expression and the regulation effect of cell growth of microRNA-577 in hepatocellular carcinoma (HCC). METHODS: qRT-PCR was applied to detect the relative expression of miR-577 in 70 paired HCC and matched tumor adjacent tissues collecting from resection between March 2011 and March 2014. Pearson chi-square test was used to analyze the relationship between the miR-577 expression and clinical features. The miR-577 mimics were transfected into HepG2 cells; cell cycles were detected by flow cytometry, cell proliferation was measured by MTT assay and BrdU incorporation assay, and cell apoptosis was determined by flow cytometry and caspase3/7 activity analysis. The expressions of ß-catenin were measured by immunohistochemistry. Spearman correlation analysis was used to analyze the relationship between miR-577 and ß-catenin. qRT-PCR and western-blot were used to detect the expression of ß-catenin in transfected HepG2 cells. RESULTS: The relative expressions of miR-577 was significantly lower in HCC tissues compared to the matched normal tumor-adjacent tissues (P < 0.05). Low expression of miR-577 was significantly associated with large tumor size (≥5 cm, P < 0.05) and advanced tumor node metastasis stage (III+IV, P < 0.05). Transfection of miR-577 mimics could inhibit repress cell proliferation, enhance cell apoptosis and block the cell cycles in G0/G1 phase (P < 0.05). miR-577 in HCC group had a significant negative correlation relationship with the expression of downstream target of ß-catenin (P < 0.05). Both the mRNA and protein expression in HepG2 cells were down-regulated after transfection (P < 0.05). CONCLUSIONS: Low expression of miR-577 is related to the malignant clinicopathological features in HCC tissues, and miR-577 may suppress HCC growth through down-regulating ß-catenin.

13.
Shanghai Kou Qiang Yi Xue ; 23(1): 39-45, 2014 Feb.
Artículo en Chino | MEDLINE | ID: mdl-24608611

RESUMEN

PURPOSE: The purpose of this study was to evaluate the effect of sand-blasted and acid-etched titanium surface on MC3T3-E1 murine pre-osteoblast cell differentiation, and investigate the pathway of regulating osteogenic differentiation of MC3T3-E1 cells on sand-blasted and acid-etched titanium surface in order to elucidate the regulatory mechanisms of surface roughness on osteoblastic differentiation. METHODS: The characteristic of PT polished titanium (PT), sand-blasted and acid-etched (SLA) titanium surface were examined by scanning electron microscopy (SEM). Real-time PCR was applied to detect the expression of osteogenic genes including Runx2, OSX, OCN and OPN of the MC3T3-E1 cells cultured on the 2 groups of substrates.ERK1/2 activities in MC3T3-T1 cells were measured by Western blot on SLA surface. The data was analyzed using SAS9.0 software package. RESULTS: The result of SEM observation showed that the PT surface was turned titanium surfaces with the mean peak to valley roughness (Ra) of 0.2 µm and the corresponding Ra value of SLA was 3.2 µm. The expression levels of Runx2, OSX, OPN and OCN were significantly higher and the cell proliferation was significantly lower on SLA surfaces than on PT surfaces (P<0.05). The expression levels of Runx2, OSX, OPN and OCN were up-regulated by the effect of SLA surface with PD98095. Compared with PT surface, ERK1/2 phosphorylation was continuously inhibited by SLA. Moreover, PT surfaces treated with PD98095 and SLA surfaces without PD98095 both demonstrated reduced ERK1/2 phosphorylation of the cells and the inhibitive effect of SLA surfaces was milder than that of PD98095. CONCLUSIONS: Surface roughness is an important factor that determines osteoblast behaviors. Surface roughness of titanium substrates seems to enhance the osteoblastic differentiation of MC3T3-E1 cells and the enhancing effect of surface roughness on cell differentiation may be mediated by suppressing the activity of ERK1/2 pathway.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular , Osteogénesis , Animales , Diferenciación Celular , Proliferación Celular , Ratones , Osteoblastos , Propiedades de Superficie , Titanio
14.
Bing Du Xue Bao ; 29(1): 39-43, 2013 Jan.
Artículo en Chino | MEDLINE | ID: mdl-23547378

RESUMEN

To confirm the hypothesis that the high frequency sequences of high throughput sequencing are the terminal sequences of the bacteriophage genome. An adaptor of specific sequence was linked to the end of the bacteriophage T3 genomic DNA, which was then subject to high throughput sequencing; as a control, the same T3 genomic DNA without adaptor was also analyzed by high throughput sequencing. The sequencing results were examined with bioinformatics software. Similar high throughput sequencing technique was applied to analyze the genomic sequence of N4-like bacteriophage IME11. Bioinformatics study showed that the sequences tagged with adaptors were consistent with the high frequency sequences without adaptor labeling. Our analysis also indicated that the end of the T4-like phage genome had specific sequences instead of random sequences, disagreeing with the previous assertion. Evidences were provided that N4-like bacteriophage had a particular terminal sequence: the left end of the genome was unique while the right end was permuted. The high throughput sequencing technique was convenient and practical to be used to simultaneously detect the terminal sequence and the complete sequence of bacteriophage genome.


Asunto(s)
Caudovirales/genética , Genoma Viral , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Biología Computacional
15.
Huan Jing Ke Xue ; 33(2): 565-73, 2012 Feb.
Artículo en Chino | MEDLINE | ID: mdl-22509598

RESUMEN

The characteristics of methane (CH4) fluxes from tidal wetlands of the Yellow River estuary were observed in situ with static-chamber and GC methods in September and October 2009, and the key factors affecting CH4 fluxes were discussed. From the aspect of space, the CH4 flux ranges in high tidal wetland, middle tidal wetland, low tidal wetland, bare flat are - 0.206-1.264, -0.197-0.431, -0.125-0.659 and -0.742-1.767 mg x (m2 x h)(-1), the day average fluxes are 0.089, 0.038, 0.197 and 0.169 mg x (m2 x h)(-1), respectively, indicating that the tidal wetlands are the sources of CH4 and the source function of CH4 differed among the four study sites, in the order of low tidal wetland > bare flat > high tidal wetland > middle tidal wetland. From the aspect of time, the ranges of CH4 fluxes from the tidal wetland ecosystems are -0.444-1.767 and - 0.742- 1.264 mg x (m2 x h)(-1), and the day average fluxes are 0.218 and 0.028 mg x (m2 x h)(-1) in September and October, respectively. The CH4 fluxes in each tidal wetland in September are higher than those in October except that the high tidal wetland acts as weak sink in September. Further studies indicate that the changes of environmental factors in the Yellow River estuary are complicated, and the CH4 fluxes are affected by multiple factors. The differences of CH4 fluxes characteristics among different tidal wetlands in autumn are probably related to temperature (especially atmospheric temperature) and vegetation growth status, while the effects of water or salinity condition and tide status on the CH4 flux characteristics might not be ignored.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Metano/análisis , Contaminantes Químicos del Agua/análisis , Humedales , China , Océanos y Mares , Ríos , Estaciones del Año , Olas de Marea
16.
J Biomed Mater Res A ; 100(1): 125-33, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21997903

RESUMEN

Surface roughness of titanium-based implants may enhance osteogenic differentiation of cells in vitro and bone-to-implant contact in vivo. Nevertheless, how surface roughness regulates the signaling pathway of osteoblasts is little understood. The study intended to investigate specifically the roles of extracellular signal-regulated kinase 1/2 (ERK1/2) pathway in regulating osteogenic differentiation of MC3T3-E1 murine preosteoblast cells on Ti surfaces. Substrates applied were two groups of titanium disks: (1) sand-blasted and acid-etched rough surfaces (SLA) and (2) smooth pretreated Ti surfaces (PT). Surface morphology of the two groups was examined by scanning electron microscope, and cell morphology cultured on Ti disks was observed by confocal microscope. The levels of alkaline phosphatase (ALP) activity and calcium deposition were measured and compared between the two groups. Real-time polymerase chain reaction was applied to detect the expression levels of osteogenic genes including runt related protein 2 (Runx2), osterix (OSX), osteocalcin (OCN) and osteoprotegerin (OPN) of the cells cultured on the two groups of substrates and on SLA surfaces treated with ERK1/2 inhibitor, PD98095. ERK1/2 activities in MC3T3-T1 cells were measured by Western-blotting on the two surfaces with or without PD98095. Cells cultured on rougher SLA surfaces displayed a more differentiated morphology. ALP activities at 7 days and 14 days and the calcium deposition at 28 days were significantly higher on SLA surfaces. The expression levels of Runx2, OSX, OPN and OCN were upregulated by the effect of surface roughness and PD98095 further upregulated the expression levels of these osteogenic genes on SLA surfaces. ERK1/2 phosphorylation was continuously inhibited by surface roughness at 2 days, 4 days and 6 days. In contrast, no marked alterations in ERK1/2 phosphorylation on PT surfaces were observed. PT surfaces treated with PD98095 (50 µM) and SLA surfaces without PD98095 both demonstrated reduced ERK1/2 phosphorylation of the cells, and the inhibitive effect of SLA surfaces was milder than that of PD98095. In conclusion, ERK1/2 pathway may be a negative regulator of cell differentiation in a dosage-dependent manner, and the enhancing effect of surface roughness on osteoblastic differentiation may be mediated through inhibiting ERK1/2 pathway.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Osteoblastos/citología , Osteoblastos/enzimología , Osteogénesis/efectos de los fármacos , Titanio/farmacología , Fosfatasa Alcalina/metabolismo , Animales , Western Blotting , Calcificación Fisiológica/efectos de los fármacos , Diferenciación Celular/genética , Forma de la Célula/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Regulación de la Expresión Génica/efectos de los fármacos , Ratones , Microscopía Confocal , Microscopía Electrónica de Rastreo , Osteoblastos/efectos de los fármacos , Osteogénesis/genética , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Reacción en Cadena en Tiempo Real de la Polimerasa , Propiedades de Superficie/efectos de los fármacos , Titanio/química
17.
Zhonghua Nan Ke Xue ; 18(12): 1105-7, 2012 Dec.
Artículo en Chino | MEDLINE | ID: mdl-23405792

RESUMEN

OBJECTIVE: To investigate the clinical effects of the combined therapy of the Chinese medicine Compound Xuanju Capsule and vitamin E on sperm chromatin damage in idiopathic oligoasthenospermia. METHODS: We assigned 50 infertile men with seminal abnormality to a control group (n = 26) and a trial group (n = 24) to receive vitamin E and the combined therapy of Compound Xuanju Capsule plus vitamin E, respectively, both treated for 3 months. Before and after the treatment, we detected semen routine parameters and sperm DNA fragmentation indexes (DFI) by computer aided semen analysis (CASA) and sperm chromatin structure assay (SCSA), and compared them between the two groups. RESULTS: There was no obvious difference between the percentage of progressively motile sperm in the trial group and that in the control group (21.55 +/- 8.68 vs 21.47 +/- 11.53, P > 0.05). The trial group showed a significantly decreased sperm DFI after medication as compared with pre-medication (29.57 +/- 12.19 vs 34.09 +/- 10.32, P < 0.05). CONCLUSION: The combined therapy of Compound Xuanju Capsule and vitamin E can effectively improve seminal quality and reduce sperm chromatin damage in infertile men with idiopathic oligoasthenospermia.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Infertilidad Masculina/genética , Espermatozoides/efectos de los fármacos , Vitamina E/farmacología , Adulto , Cápsulas , Cromatina/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Fragmentación del ADN , Quimioterapia Combinada , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Infertilidad Masculina/tratamiento farmacológico , Masculino , Vitamina E/uso terapéutico , Adulto Joven
18.
Shanghai Kou Qiang Yi Xue ; 20(2): 119-24, 2011 Apr.
Artículo en Chino | MEDLINE | ID: mdl-21566858

RESUMEN

PURPOSE: To investigate the distribution of sensory nerve fibers in the tissue of peri-implant bone and to study the reconstruction procedure of somatosensory evoked potentials of unloaded dental implant. METHODS: The bilateral 2nd, 3rd and 4th mandibular premolars and the 1st molars were extracted from 3 beagle dogs. Three months later, 4 screw-type implants were inserted. Then 1, 6 and 12 weeks later, the sensory nerve action potential(SNAP) tests were performed. The stimulating electrode was connected to the implant, and the recording electrodes were fixed on the inferior alveolar nerve stem to record the amplitude of SNAP. Then the dogs were sacrificed, and the specimens were prepared for immunohistochemical examination. The SNAP results were statistically analyzed using SPSS17.0 software package. RESULTS: SNAP of the inferior alveolar nerve stem could be recorded following stimulations to each implant. The difference in SNAP amplitudes between the 1-week group and the other two groups was significant (P<0.05) But there was no significant difference between the 6-week and 12-week group. Some NFP-positive nerve fibers were found in the tissues of peri-implant bone. These fibers localized in both the bone marrow space and in the peri-implant fibrous tissues. CONCLUSIONS: Neuroreceptors do exist in the tissue of peri-implant bone, but much less than the periodontal ligament. These neuroreceptors could receive electrical stimulus then evoke SNAP of the inferior alveolar nerve stem. In unloaded condition, the reconstruction of never endings in the peri-implant bone tissue is apparently time-dependent.


Asunto(s)
Implantes Dentales , Oseointegración , Animales , Diente Premolar , Perros , Diente Molar , Fibras Nerviosas , Ligamento Periodontal , Sensación
19.
Virol Sin ; 26(1): 54-60, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21331891

RESUMEN

Although previous publications suggest the 2009 pandemic influenza A (H1N1) virus was reassorted from swine viruses of North America and Eurasia, the immediate ancestry still remains elusive due to the big evolutionary distance between the 2009 H1N1 virus and the previously isolated strains. Since the unveiling of the 2009 H1N1 influenza, great deal of interest has been drawn to influenza, consequently a large number of influenza virus sequences have been deposited into the public sequence databases. Blast analysis demonstrated that the recently submitted 2007 South Dakota avian influenza virus strains and other North American avian strains contained genetic segments very closely related to the 2009 H1N1 virus, which suggests these avian influenza viruses are very close relatives of the 2009 H1N1 virus. Phylogenetic analyses also indicate that the 2009 H1N1 viruses are associated with both avian and swine influenza viruses circulating in North America. Since the migrating wild birds are preferable to pigs as the carrier to spread the influenza viruses across vast distances, it is very likely that birds played an important role in the inter-continental evolution of the 2009 H1N1 virus. It is essential to understand the evolutionary route of the emerging influenza virus in order to find a way to prevent further emerging cases. This study suggests the close relationship between 2009 pandemic virus and the North America avian viruses and underscores enhanced surveillance of influenza in birds for understanding the evolution of the 2009 pandemic influenza.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/genética , Virus de la Influenza A/genética , Animales , Aves/virología , Humanos , Subtipo H1N1 del Virus de la Influenza A/clasificación , Virus de la Influenza A/clasificación , Gripe Aviar/virología , Filogenia , South Dakota , Porcinos/virología
20.
Zhonghua Nan Ke Xue ; 17(12): 1083-6, 2011 Dec.
Artículo en Chino | MEDLINE | ID: mdl-22235675

RESUMEN

OBJECTIVE: To explore the predictive value of sperm chromatin integrity test (SCIT) in assisted reproductive technology (ART) by analyzing the relationship of sperm chromatin integrity (SCI) with the outcomes of IVF-ET and ICSI. METHODS: Sperm chromatin structure assay (SCSA) was performed to test SCI in 187 ART cycles, and the results were expressed as DNA fragmentation index (DFI). According to the level of DFI, the 187 cycles were allocated to a high DFI group (DFI > or = 30% ) and a low DFI group (DFI < 30%), each of which was again divided into an IVF and an ICSI subgroup. Comparisons were made between the IVF and ICSI subgroups of the high and low DFI groups in the fertilization rate, cleavage rate, embryo quality, and clinical pregnancy rate. RESULTS: The clinical pregnancy rate of ICSI was significantly higher than that of IVF in the high DFI group, while the clinical outcomes showed no significant differences between the high and low DFI groups in either the IVF or the ICSI subgroup. CONCLUSION: Sperm DNA damage affects the outcome of ART, and therefore SCIT can be used as a supplementary option to standard semen analysis in choosing the method for ART.


Asunto(s)
Cromatina , Fragmentación del ADN , Espermatozoides/citología , Adulto , Femenino , Fertilización In Vitro , Humanos , Masculino , Valor Predictivo de las Pruebas , Embarazo , Índice de Embarazo , Análisis de Semen , Inyecciones de Esperma Intracitoplasmáticas
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