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1.
Opt Express ; 32(11): 20024-20034, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859121

RESUMO

An optical fiber sensing probe using a composite sensitive film of polyacrylonitrile (PAN) nanofiber membrane and gold nanomembrane is presented for the detection of a carcinoembryonic antigen (CEA), a biomarker associated with colorectal cancer and other diseases. The probe is based on a tilted fiber Bragg grating (TFBG) with a surface plasmon resonance (SPR) gold nanomembrane and a functionalized polyacrylonitrile (PAN) PAN nanofiber coating that selectively binds to CEA molecules. The performance of the probe is evaluated by measuring the spectral shift of the TFBG resonances as a function of CEA concentration in buffer. The probe exhibits a sensitivity of 0.46 dB/(µg/ml), a low limit of detection of 505.4 ng/mL in buffer, and a good selectivity and reproducibility. The proposed probe offers a simple, cost-effective, and a novel method for CEA detection that can be potentially applied for clinical diagnosis and monitoring of CEA-related diseases.


Assuntos
Resinas Acrílicas , Antígeno Carcinoembrionário , Ouro , Nanofibras , Fibras Ópticas , Ressonância de Plasmônio de Superfície , Antígeno Carcinoembrionário/análise , Ouro/química , Nanofibras/química , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos , Resinas Acrílicas/química , Humanos , Técnicas Biossensoriais/instrumentação , Membranas Artificiais , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Tecnologia de Fibra Óptica/instrumentação
2.
Environ Res ; 250: 118442, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38368919

RESUMO

Heavy metal pollution, particularly the excessive release of copper (Cu), is an urgent environmental concern. In this study, sodium lignosulfonate/carboxymethyl sa-son seed gum (SL-Cg-g-PAA) designed for remediation of Cu-contaminated water and soil was successfully synthesized through a free radical polymerization method using lignin as a raw material. This hydrogel exhibits remarkable Cu adsorption capability when applied to water, with a maximum adsorption capacity reaching 172.41 mg/g. Important adsorption mechanisms include surface complexation and electrostatic attraction between Cu(Ⅱ) and oxygen-containing functional groups (-OH, -COOH), as well as cation exchange involving -COONa and -SO3Na. Furthermore, SL/Cg-g-PAA effectively mitigated the bioavailability of heavy metals within soil matrices, as evidenced by a notable 14.1% reduction in DTPA extracted state Cu (DTPA-Cu) content in the S4 treatment (0.7% SL/Cg-g-PAA) compared to the control group. Concurrently, the Cu content in both the leaves and roots of pakchoi exhibited substantial decreases of 55.19% and 36.49%, respectively. These effects can be attributed to the precipitation and complexation reactions facilitated by the hydrogel. In summary, this composite hydrogel is highly promising for effective remediation of heavy metal pollution in water and soil, with a particular capability for the immobilization of Cu(Ⅱ) and reduction of its adverse effects on ecosystems.


Assuntos
Cobre , Recuperação e Remediação Ambiental , Hidrogéis , Lignina , Poluentes do Solo , Poluentes Químicos da Água , Hidrogéis/química , Cobre/química , Lignina/química , Lignina/análogos & derivados , Poluentes do Solo/química , Adsorção , Poluentes Químicos da Água/química , Recuperação e Remediação Ambiental/métodos
3.
Int J Mol Sci ; 25(12)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38928100

RESUMO

Rich biological information in sweat provides great potential for health monitoring and management. However, due to the complexity of sweat, the development of environmentally friendly green electronic products is of great significance to the construction of ecological civilization. This study utilized a simple combination of polystyrene sulfonate sodium (PSS) and filter paper (FP) to prepare cellulose materials coated with conductive polymers, developing an electrochemical sensor based on the modified materials. The mechanical and electrochemical properties of the fabricated PSS/FP membrane were optimized by adjusting the feeding dosage of PSS. The realized PSS/FP composite containing 7% PSS displayed good conductivity (9.1 × 10-2 S/m), reducing electric resistance by 99.2% compared with the original FP membrane (6.7 × 10-4 S/m). The stable current of the membrane in simulated sweat under different pH environments is highly correlated with the pH values. Additionally, when the membrane is exposed to simulated sweat with varying ion concentrations, the current signal changes in real time with the concentration variations. The response time averages around 0.3 s.


Assuntos
Celulose , Condutividade Elétrica , Poliestirenos , Suor , Suor/química , Celulose/química , Concentração de Íons de Hidrogênio , Poliestirenos/química , Polímeros/química , Humanos , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos
4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(3): 595-603, 2024 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-38932547

RESUMO

The stiffness of an ideal fracture internal fixation implant should have a time-varying performance, so that the fracture can generate reasonable mechanical stimulation at different healing stages, and biodegradable materials meet this performance. A topology optimization design method for composite structures of fracture internal fixation implants with time-varying stiffness is proposed, considering the time-dependent degradation process of materials. Using relative density and degradation residual rate to describe the distribution and degradation state of two materials with different degradation rates and elastic modulus, a coupled mathematical model of degradation simulation mechanical analysis was established. Biomaterial composite structures were designed based on variable density method to exhibit time-varying stiffness characteristics. Taking the bone plate used for the treatment of tibial fractures as an example, a composite structure bone plate with time-varying stiffness characteristics was designed using the proposed method. The optimization results showed that material 1 with high stiffness formed a columnar support structure, while material 2 with low stiffness was distributed at the degradation boundary and inside. Using a bone remodeling simulation model, the optimized bone plates were evaluated. After 11 months of remodeling, the average elastic modulus of callus using degradable time-varying stiffness plates, titanium alloy plates, and stainless steel plates were 8 634 MPa, 8 521 MPa, and 8 412 MPa, respectively, indicating that the use of degradable time-varying stiffness plates would result in better remodeling effects on the callus.


Assuntos
Placas Ósseas , Remodelação Óssea , Módulo de Elasticidade , Fixação Interna de Fraturas , Fraturas da Tíbia , Titânio , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Humanos , Fraturas da Tíbia/cirurgia , Titânio/química , Materiais Biocompatíveis/química , Teste de Materiais , Estresse Mecânico , Ligas , Implantes Absorvíveis
5.
Oral Dis ; 29(6): 2449-2462, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36648381

RESUMO

The second most frequent craniomaxillofacial congenital deformity is hemifacial microsomia (HFM). Patients often accompany short mandible, ear dysplasia, facial nerve, and soft tissue dysplasia. The etiology of HFM is not fully understood. To organize the possible up-to-date information on the etiology, craniofacial phenotypes, and therapeutic alternatives in order to fully comprehend the HFM. Reviewing the potential causes, exploring the clinical features of HFM and summarizing the available treatment options. Vascular malformation, Meckel's cartilage abnormalities, and cranial neural crest cells (CNCCs) abnormalities are three potential etiology hypotheses. The commonly used clinical classification for HFM is OMENS, OMENS-plus, and SAT. Other craniofacial anomalies, like dental defects, and zygomatic deformities, are still not precisely documented in the classification. Patients with moderate phenotypes may not need any treatment from infancy through adulthood. However, patients with severe HFM require to undergo multiple surgeries to address facial asymmetries, such as mandibular distraction osteogenesis (MDO), autologous costochondral rib graft (CCG), orthodontic and orthognathic treatment, and facial soft tissue reconstruction. It is anticipated that etiology research will examine the pathogenic mechanism of HFM. A precise treatment for HFM may be possible with thoroughly documented phenotypes and a pathogenic diagnosis.


Assuntos
Síndrome de Goldenhar , Humanos , Síndrome de Goldenhar/cirurgia , Síndrome de Goldenhar/complicações , Assimetria Facial/etiologia , Mandíbula/patologia
6.
J Craniofac Surg ; 34(2): e195-e198, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36217236

RESUMO

BACKGROUND: Maxillary hypoplasia is common in patients with cleft lip and palate. In this study, the authors investigated the soft tissue changes in midfacial regions after anterior maxillary segmental distraction osteogenesis (AMSDO) in patients with cleft. METHODS: Eight patients with cleft lip and palate who underwent AMSDO were enrolled in this study. Spiral computed tomographic images were taken before surgery and 6-12 months after surgery to evaluate soft tissue changes after AMSDO. The midfacial area was divided into 6 regions of interest according to anatomical subunits. The average movements of each region were calculated using volumetric changes and preoperative region surface areas. RESULTS: The upper lip on both sides has the most anterior movement (5.22±0.86 and 5.14±0.84 mm), supracommissural regions have a little less movement (4.11±0.55 and 3.81±0.67 mm), paranasal regions have the least movement (3.37±0.47 and 3.15±0.36 mm). The corresponding regions of interest showed no significant difference on the cleft side versus the noncleft side. CONCLUSIONS: Anterior maxillary segmental distraction osteogenesis can improve the soft tissue profile in patients with cleft, and there was no significant difference in soft tissue changes between the cleft side and the noncleft side.


Assuntos
Fenda Labial , Fissura Palatina , Osteogênese por Distração , Humanos , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Osteogênese por Distração/métodos , Resultado do Tratamento , Maxila/cirurgia , Osteotomia de Le Fort/métodos , Cefalometria
7.
Nano Lett ; 22(18): 7506-7514, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36094850

RESUMO

Here we report the use of defects in ordered solvents to form, manipulate, and characterize individual molecular assemblies of either small-molecule amphiphiles or polymers. The approach exploits nanoscopic control of the structure of nematic solvents (achieved by the introduction of topological defects) to trigger the formation of molecular assemblies and the subsequent manipulation of defects using electric fields. We show that molecular assemblies formed in solvent defects slow defect motion in the presence of an electric field and that time-of-flight measurements correlate with assembly size, suggesting methods for the characterization of single assemblies of molecules. Solvent defects are also used to transport single assemblies of molecules between solvent locations that differ in composition, enabling the assembly and disassembly of molecular "nanocontainers". Overall, our results provide new methods for studying molecular self-assembly at the single-assembly level and new principles for integrated nanoscale chemical systems that use solvent defects to transport and position molecular cargo.


Assuntos
Polímeros , Polímeros/química , Solventes/química
8.
Int J Mol Sci ; 24(7)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37047390

RESUMO

Lignin has many potential applications and is a biopolymer with a three-dimensional network structure. It is composed of three phenylpropane units, p-hydroxyphenyl, guaiacyl, and syringyl, connected by ether bonds and carbon-carbon bonds, and it contains a large number of phenol or aldehyde structural units, resulting in complex lignin structures. This limits the application of lignin. To expand the application range of lignin, we prepared lignin thermoplastic phenolic resins (LPRs) by using lignin instead of phenol; these LPRs had molecular weights of up to 1917 g/mol, a molecular weight distribution of 1.451, and an O/P value of up to 2.73. Due to the complex structure of the lignin, the synthetic lignin thermoplastic phenolic resins were not very tough, which greatly affected the performance of the material. If the lignin phenolic resins were toughened, their application range would be substantially expanded. Polybutylene succinate (PBS) has excellent processability and excellent mechanical properties. The toughening effects of different PBS contents in the LPRs were investigated. PBS was found to be compatible with the LPRs, and the flexible chain segments of the small PBS molecules were embedded in the molecular chain segments of the LPRs, thus reducing the crystallinities of the LPRs. The good compatibility between the two materials promoted hydrogen bond formation between the PBS and LPRs. Rheological data showed good interfacial bonding between the materials, and the modulus of the high-melting PBS made the LPRs more damage resistant. When PBS was added at 30%, the tensile strength of the LPRs was increased by 2.8 times to 1.65 MPa, and the elongation at break increased by 31 times to 93%. This work demonstrates the potential of lignin thermoplastic phenolic resins for industrial applications and provides novel concepts for toughening biobased aromatic resins with PBS.


Assuntos
Materiais Biocompatíveis , Lignina , Lignina/química , Materiais Biocompatíveis/química , Fenóis , Resinas Sintéticas
9.
J Med Virol ; 94(6): 2598-2606, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35149996

RESUMO

Coxsackievirus B2 (CVB2) is an enterovirus B (EV-B) species and can cause aseptic meningitis, myocarditis and hand, foot, and mouth disease (HFMD). We characterized a novel CVB2 (YN31V3) associated with HFMD in Yunnan, Southwest China, in 2019. Although YN31V3 and other Mainland China epidemic strains mainly belonged to genotype C, YN31V3 formed an independent branch. The genome sequence of the strain YN31V3 from this study showed a 12.91% nucleotide difference to its closest strain RW41-2/YN/CHN/2012. Recombination analyses showed that the newly isolated YN31V3 was probably a recombinant, which was closely related to CVB2 strains in the genomic P1 region and other EV-B strains in the P2 and P3 regions, respectively. YN31V3 strain had a temperature-sensitive phenotype. The challenge of suckling BALB/c mice with YN31V3 could cause symptoms of disease and severe pathological lesions.


Assuntos
Enterovirus , Doença de Mão, Pé e Boca , Animais , China/epidemiologia , Enterovirus/genética , Enterovirus Humano B , Genoma Viral , Genótipo , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/genética , Humanos , Camundongos , Filogenia
10.
J Med Virol ; 94(2): 601-609, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34387895

RESUMO

Hand, foot, and mouth disease (HFMD) is a contagious disease that threatens the health of children under 5 years of age. Coxsackievirus A10 (CV-A10) is one of the main pathogens of HFMD. Currently, preventive vaccines and specific therapeutic drugs are not available for CV-A10. In this study, a total of 327 stool specimens were collected from pediatric patients from 2009 to 2017 during HFMD surveillance, among which 14 CV-A10 strains could only be isolated from rhabdomyosarcoma cells, but not from KMB17 and Vero cells. Through adaptive culture, 2 and 11 CV-A10 strains were recovered from Vero and KMB17 cell cultures, respectively. The growth of CV-A10 strains in Vero cells was better than that in KMB17 cells. The 14 CV-A10 strains belonged to the F genotype, and the nucleotides and amino acids of their complete genomes shared 92.6%-96.3% and 98.4%-98.9% identities, respectively. The different CV-A10 strains exhibited varying virulence in vivo, but had similar effects on tissue injury, with the hind limb muscles, kidneys, and lungs being severely affected. Additionally, the hind limb muscles had the highest viral loads. CV-A10 was found to exhibit a strong tropism to muscle tissue. The results of this study are critical to developing vaccines against CV-A10 infections.


Assuntos
Enterovirus Humano A/genética , Doença de Mão, Pé e Boca/virologia , Animais , Pré-Escolar , Chlorocebus aethiops , Enterovirus Humano A/isolamento & purificação , Feminino , Genótipo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células Vero
11.
BMC Infect Dis ; 22(1): 671, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927711

RESUMO

BACKGROUND: Hand, foot, and mouth disease (HFMD) is a common child infectious disease caused by more than 20 enterovirus (EV) serotypes. In recent years, enterovirus A71 (EV-A71) has been replaced by Coxsackievirus A6 (CV-A6) to become the predominant serotype. Multiple EV serotypes co-circulate in HFMD epidemics, and this study aimed to investigate the etiological epidemic characteristics of an HFMD outbreak in Kunming, China in 2019. METHODS: The clinical samples of 459 EV-associated HFMD patients in 2019 were used to amplify the VP1 gene region by the three sets of primers and identify serotypes using the molecular biology method. Phylogenetic analyses were performed based on the VP1 gene. RESULTS: Three hundred and forty-eight cases out of 459 HFMD patients were confirmed as EV infection. Of these 191 (41.61%) were single EV infections and 34.20% had co-infections. The EVs were assigned to 18 EV serotypes, of which CV-A6 was predominant (11.33%), followed by CV-B1 (8.93%), CV-A4 (5.23%), CV-A9 (4.58%), CV-A 16 (3.49%) and CV-A10 and CVA5 both 1.96%. Co-infection of CV-A6 with other EVs was present in 15.25% of these cases, followed by co-infection with CV-A16 and other EVs. The VP1 sequences used in the phylogenetic analyses showed that the CV-A6, CV-B1 and CV-A4 sequences belonged to the sub-genogroup D3 and genogroups F and E, respectively. CONCLUSION: Co-circulation and co-infection of multiple serotypes were the etiological characteristic of the HFMD epidemic in Kunming China in 2019 with CV-A-6, CV-B1 and CV-A4 as the predominant serotypes. This is the first report of CV-B1 as a predominant serotype in China and may provide valuable information for the diagnosis, prevention and control of HFMD.


Assuntos
Coinfecção , Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , Doença de Mão, Pé e Boca , Criança , China/epidemiologia , Coinfecção/epidemiologia , Enterovirus/genética , Enterovirus Humano B , Infecções por Enterovirus/epidemiologia , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Lactente , Vacinação em Massa , Filogenia
12.
BMC Vet Res ; 18(1): 373, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36253821

RESUMO

BACKGROUND: The existing detection methods for porcine circovirus type 2 (PCV2) specific antibodies in serum cannot determine the infection status, thus it is necessary to establish a method for detecting PCV2 antigen. The capsid protein (CAP) of PCV2, as a major structural protein that plays a significant role in viral replication and in inducing host's immune response, is an ideal target antigen to monitor PCV2 infection. Therefore, a gold immunochromatographic assay (GICA) for rapid detection of PCV2 antigen based on the polyclonal antibodies (PAbs) against PCV2-CAP will be developed. RESULTS: The truncated CAP protein (dCAP) was used to immunize rabbits to generate anti-serum. After preliminary purification by caprylic acid/ammonium sulfate precipitation (CAAS), specific PAbs were purified by affinity chromatography column coupled with dCAP and its titer was about two-fold higher than preliminary purified PAbs. Colloidal gold-PAbs conjugate was synthesized under the optimum conditions. The specific anti-dCAP PAbs and goat anti-rabbit antibody (GAR) were then sprayed onto nitrocellulose (NC) membrane as a test line (TL) and a control line (CL), respectively. The visual limit detection (vLOD) of the GICA strips was 5 ng/mL. Specificity assay indicated that the GICA strips had specifically detected PCV2 and was not reactive for porcine epidemic diarrhea virus (PEDV), pseudorabies virus (PRV), porcine reproductive and respiratory syndrome virus (PRRSV) or classic swine fever virus (CSFV). A total of 36 porcine serum samples were detected by this GICA and commercial enzyme-linked immunosorbent assay (ELISA) Kit, 9 positive samples were found by the developed strip with the rate of 25.0% comparing with 11 positive samples detected by the commercially ELISA Kit which positive rate was 30.5%, and the receiver operating characteristic (ROC) curve revealed that the relative sensitivity and specificity of this GICA strip were 72.7 and 96.0%, respectively, with an area of 87.2%. CONCLUSIONS: This study established an efficient detection method with high sensitivity and specificity for the clinical diagnosis of PCV2 antigen, that will facilitate a rapid and convenient way to evaluate the infection status of vaccinated pigs.


Assuntos
Infecções por Circoviridae , Circovirus , Doenças dos Suínos , Sulfato de Amônio , Animais , Anticorpos Antivirais , Proteínas do Capsídeo , Infecções por Circoviridae/diagnóstico , Infecções por Circoviridae/veterinária , Colódio , Coloide de Ouro/química , Imunoensaio/veterinária , Coelhos , Suínos
13.
Am J Orthod Dentofacial Orthop ; 162(3): 331-339, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35504773

RESUMO

INTRODUCTION: This study aimed to use 3-dimensional data to analyze the relationship between local alveolar bone housing and canine size in maxillary canine-lateral incisor transposition. METHODS: Cone-beam computed tomography study data from 31 patients with maxillary canine-lateral incisor transposition were imported into Dolphin Imaging software (version 11.8; Dolphin Imaging and Management Solutions, Chatsworth, Calif) for measurement. The buccal and palatal alveolar thickness of lateral incisor roots at different heights, the maximal thickness of displaced canine, and canine height were measured. Alveolar height-thickness variation curves at the lateral incisor region and maximal thickness of displaced canine were plotted to calculate the appropriate theoretical minimum alveolar heights of total alveolar housing, buccal alveolar housing after concentrating the bone buccally (TMAH-B1), and original buccal alveolar housing (TMAH-B2) required for correcting the transposition of 2 teeth. RESULTS: Canines could only be moved distally above lateral incisors in 5 patients. The mean value of theoretical minimum alveolar heights of total alveolar housing was 14.57 ± 1.75 mm. It was possible to reposition canines distally by concentrating the alveolar bone buccally in the remaining 26 patients. The mean value of TMAH-B1 was 10.86 ± 3.70 mm. Canines could be repositioned distally directly over the buccal aspect of the lateral incisor in 17 patients. The mean value of TMAH-B2 was 9.30 ± 2.35 mm. Canine height was greater than TMAH-B1 in 18 patients; however, only 10 patients were greater than TMAH-B2. CONCLUSIONS: Correction of transposition was difficult in some patients because of the lack of alveolar bone housing. Repositioning was possible when the height of the canine was higher than a certain height. An accurate assessment of the relationship between alveolar housing and tooth size is recommended.


Assuntos
Dente Canino , Incisivo , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Canino/diagnóstico por imagem , Habitação , Incisivo/diagnóstico por imagem , Maxila/diagnóstico por imagem , Estudos Retrospectivos
14.
Am J Orthod Dentofacial Orthop ; 161(4): 548-556, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35042634

RESUMO

INTRODUCTION: The purpose of this trial was to use 3-dimensional data to analyze the differences of root morphology and root length between 3 different types of impacted maxillary central incisors. METHODS: Cone-beam computed tomography images of 126 patients with impacted maxillary central incisors were included in this retrospective study. On the basis of the angle of the impacted incisor to the palatal plane, we categorized the tooth as labial inversely impacted, labially positioned, or palatal impacted incisor. In each category, the early and late dental age groups were classified according to the method of Nolla. The total root length of both impacted and homonym teeth, length of the nondilacerated part of the root, length of the dilacerated part of the root, the angle between the crown and root, and root direction, were measured in the sagittal-view sections using Dolphin Imaging software (version 11.9; Dolphin Imaging and Management Solutions, Chatsworth, Calif). RESULTS: Compared with the early dental age groups, the length of the dilacerated portion of the root and rate of dilaceration for inverse labial and labially positioned impactions increases, and crown-root angle decreases (P <0.05). The dilacerated part of the root bent labially, and the root morphology shows an obvious L-shaped curve. The length of the nondilacerated part of the root for palatal impactions is greater(P <0.05). The dilacerated part of the root bends palatally, and the root morphology shows a continuous C-shaped curve. CONCLUSIONS: Obstruction from the alveolar bone will cause different root morphology. Root morphology of labial impactions shows an obvious L-shaped curve; palatal impactions show a continuous C-shaped curve.


Assuntos
Incisivo , Dente Impactado , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Incisivo/diagnóstico por imagem , Maxila/diagnóstico por imagem , Estudos Retrospectivos , Dente Impactado/diagnóstico por imagem
15.
Angew Chem Int Ed Engl ; 60(32): 17464-17471, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-33913253

RESUMO

Melanosomes in nature have diverse morphologies, including spheres, rods, and platelets. By contrast, shapes of synthetic melanins have been almost entirely limited to spherical nanoparticles with few exceptions produced by complex templated synthetic methods. Here, we report a non-templated method to access synthetic melanins with a variety of architectures including spheres, sheets, and platelets. Three 1,8-dihydroxynaphthalene dimers (4-4', 2-4' and 2-2') were used as self-assembling synthons. These dimers pack to form well-defined structures of varying morphologies depending on the isomer. Specifically, distinctive ellipsoidal platelets can be obtained using 4-4' dimers. Solid-state polymerization of the preorganized dimers generates polymeric synthetic melanins while maintaining the initial particle morphologies. This work provides a new route to anisotropic synthetic melanins, where the building blocks are preorganized into specific shapes, followed by solid-state polymerization.


Assuntos
Corantes/química , Naftóis/química , Polímeros/química , Anisotropia , Corantes/síntese química , Naftóis/síntese química , Polimerização , Polímeros/síntese química
16.
J Med Virol ; 92(8): 1085-1092, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31850595

RESUMO

Enterovirus A71 (EV-A71) infection is known to cause hand, foot, and mouth disease (HFMD). Last year, an inactivated EV-A71 whole virus vaccine was used to prevent this disease in Yunnan, China. To obtain a viral genetic background for evaluating vaccine protection and monitor the adaptive evolution of the virus after the vaccination, a 5-year molecular epidemiology survey was performed before the vaccination. Twenty-six EV-A71 strains were separated from 561 stool specimens of patients with serious HFMD. The whole-genomic sequences of these strains were sequenced. Phylogenetic trees were constructed, and the mutation spectra were analyzed based on these viral sequences. There was no obvious mutation for the circular EV-A71 strains of the same year. Pathogenic EV-A71 strains may arise from a "subgroup" randomly each year. Whole-genomic analyses showed that a hotspot nonsynonymous substitution potentially affecting the immunogenicity of vaccines was found in the 2A gene, but not in genes of the viral capsid proteins, and the genetic diversity of whole viral genomes associated with the incidence of HFMD. Therefore, it will be valuable to monitor the genome-wide changes of EV-A71 to detect the adaptive mutations affecting immunogenicity or perform investigations using genetic diversity as a parameter.


Assuntos
Enterovirus Humano A/genética , Infecções por Enterovirus/epidemiologia , Genoma Viral , Filogenia , Antígenos Virais/genética , China/epidemiologia , Fezes/virologia , Variação Genética , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/virologia , Humanos , Mutação , RNA Viral/genética , Vacinação , Sequenciamento Completo do Genoma
17.
Int J Mol Sci ; 21(3)2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31979344

RESUMO

Salt and drought stresses are two primary abiotic stresses that inhibit growth and reduce the activity of photosynthetic apparatus in plants. Abscisic acid (ABA) plays a key role in abiotic stress regulation in plants. Some aldo-keto reductases (AKRs) can enhance various abiotic stresses resistance by scavenging cytotoxic aldehydes in some plants. However, there are few comprehensive reports of plant AKR genes and their expression patterns in response to abiotic stresses. In this study, we identified 30 putative AKR genes from Medicago truncatula. The gene characteristics, coding protein motifs, and expression patterns of these MtAKRs were analyzed to explore and identify candidate genes in regulation of salt, drought, and ABA stresses. The phylogenetic analysis result indicated that the 52 AKRs in Medicago truncatula and Arabidopsis thaliana can be divided into three groups and six subgroups. Fifteen AKR genes in M. truncatula were randomly selected from each group or subgroup, to investigate their response to salt (200 mM of NaCl), drought (50 g·L-1 of PEG 6000), and ABA (100 µM) stresses in both leaves and roots. The results suggest that MtAKR1, MtAKR5, MtAKR11, MtAKR14, MtAKR20, and MtAKR29 may play important roles in response to these stresses.


Assuntos
Ácido Abscísico/metabolismo , Aldo-Ceto Redutases/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Medicago truncatula/genética , Estresse Salino/genética , Estresse Fisiológico/genética , Aldo-Ceto Redutases/metabolismo , Arabidopsis/genética , Secas , Medicago truncatula/enzimologia , Medicago truncatula/metabolismo , Família Multigênica , Filogenia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Polietilenoglicóis/farmacologia , Regiões Promotoras Genéticas , Tolerância ao Sal/genética , Cloreto de Sódio/farmacologia
18.
Pharm Dev Technol ; 25(9): 1063-1070, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32589499

RESUMO

In this work, T7 modified nanoliposome loaded SNF (T7-SNF-NLPs) was developed. The physicochemical properties and characteristics of T7-SNF-NLPs, including morphology, particle size, zeta potential, stability, and in vitro release, were determined. In vitro toxicity and cellular uptake were evaluated in RKO cells. Antitumor efficiency was examined in RKO cells-bearing Kunming mice to assess their potential applications in the development of nanoliposomes therapeutics. The average particle size of T7-SNF-NLPs was observed to be 131.6 ± 1.7 nm and the polydispersity index represented a uniform mono-dispersion with PDI = 0.19. SNF was sustainably released from T7-SNF-NLPs at a release rate of 65% at 48 h in pH 7.4 PBS. The release rate of SNF was over 72% from T7-SNF-NLPs in pH 6.5 PBS, faster than that in pH 7.4, which indicated that the release rate of SNF was enhanced under the acidic environment. In vitro study clearly showed that T7 modified NLPs was more effective in inducing uptake and apoptosis in cancer cells than nonmodified NLPs. The IC50 values of T7-SNF-NLPs treated RKO cells was 9.54 µg/mL, 9.23 µg/mL for SNF-NLPs and 16.85 µg/mL for free SNF. T7-SNF-NLPs was highly efficient in suppressing the tumor growth in xenograft tumor model. The proportion of Ki67 in T7-SNF-NLPs group was significantly lower than that of either free drug or nonmodified NLPs.


Assuntos
Antineoplásicos/química , Colágeno Tipo IV/química , Neoplasias do Colo/tratamento farmacológico , Lipossomos/química , Nanopartículas/química , Fragmentos de Peptídeos/química , Receptores da Transferrina/química , Sorafenibe/química , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Humanos , Camundongos , Tamanho da Partícula , Sorafenibe/farmacologia
19.
Angew Chem Int Ed Engl ; 59(45): 19762-19772, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32436259

RESUMO

In this Minireview, we describe synthetic polymers densely functionalized with sequence-defined biomolecular sidechains. We focus on synthetic brush polymers of oligonucleotides, oligosaccharides, and oligopeptides, prepared via graft-through polymerization from biomolecule functionalized monomers. The resulting structures are brush polymers wherein a biomolecular graft is positioned at each monomer backbone unit. We describe key synthetic milestones, identify synthetic opportunities, and highlight recent advances in the field, including biological applications.


Assuntos
Oligonucleotídeos/química , Oligopeptídeos/química , Oligossacarídeos/química , Polímeros/química , Microscopia de Força Atômica
20.
Angew Chem Int Ed Engl ; 59(43): 19136-19142, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-32659039

RESUMO

Herein, we report the photoinitiated polymerization-induced self-assembly (photo-PISA) of spherical micelles consisting of proapoptotic peptide-polymer amphiphiles. The one-pot synthetic approach yielded micellar nanoparticles at high concentrations and at scale (150 mg mL-1 ) with tunable peptide loadings up to 48 wt. %. The size of the micellar nanoparticles was tuned by varying the lengths of hydrophobic and hydrophilic building blocks. Critically, the peptide-functionalized nanoparticles imbued the proapoptotic "KLA" peptides (amino acid sequence: KLAKLAKKLAKLAK) with two key properties otherwise not inherent to the sequence: 1) proteolytic resistance compared to the oligopeptide alone; 2) significantly enhanced cell uptake by multivalent display of KLA peptide brushes. The result was demonstrated improved apoptosis efficiency in HeLa cells. These results highlight the potential of photo-PISA in the large-scale synthesis of functional, proteolytically resistant peptide-polymer conjugates for intracellular delivery.


Assuntos
Apoptose , Luz , Nanopartículas/química , Peptídeos/química , Polímeros/química , Sequência de Aminoácidos , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Micelas , Polimerização
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