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1.
Int J Legal Med ; 137(6): 1693-1703, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37731065

RESUMO

Mitochondrial DNA (mtDNA) is an indispensable genetic marker in forensic genetics. The emergence and development of massively parallel sequencing (MPS) makes it possible to obtain complete mitochondrial genome sequences more quickly and accurately. The study evaluated the advantages and limitations of the ForenSeq mtDNA Whole Genome Kit in the practical application of forensic genetics by detecting human genomic DNA standards and thirty-three case samples. We used control DNA with different amount to determine sensitivity of the assay. Even when the input DNA is as low as 2.5 pg, most of the mitochondrial genome sequences could still be covered. For the detection of buccal swabs and aged case samples (bloodstains, bones, teeth), most samples could achieve complete coverage of mitochondrial genome. However, when ancient samples and hair samples without hair follicles were sequenced by the kit, it failed to obtain sequence information. In general, the ForenSeq mtDNA Whole Genome Kit has certain applicability to forensic low template and degradation samples, and these results provide the data basis for subsequent forensic applications of the assay. The overall detection process and subsequent analysis are easy to standardize, and it has certain application potential in forensic cases.

2.
Med Sci Monit ; 28: e935080, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35342190

RESUMO

BACKGROUND Cement leakage is the most common complication following percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fractures (OVCFs). Dynamic fracture mobility was determined by comparing preoperative standing lateral radiographs with intraoperative prone lateral radiographs. This retrospective study from a single center aimed to evaluate the effect of dynamic fracture mobility on cement leakage in PVP and PKP in 286 patients with OVCFs. MATERIAL AND METHODS Records of patients who underwent PVP or PKP in our department between January 2016 and December 2019 were retrospectively analyzed, showing that 156 patients received PVP and 130 patients received PKP. Variables that were significantly related to presence of cement leakage in the univariate analysis were subsequently included in a multivariate logistic regression analysis for determining the independent risk factors for cement leakage. RESULTS The univariate analysis showed that dynamic fracture mobility (P<0.001), operative approach (P=0.026), peripheral vertebrae wall damage (P<0.001), intravertebral cleft (P<0.001), and cement volume injected (P<0.001) were correlated with cement leakage. Factors that showed differences by univariate analysis underwent multivariate logistic regression analysis, showing that peripheral vertebrae wall damage (OR=11.774,95% CI 4.384-31.619, P=0.000), dynamic fracture mobility (OR=5.884, 95% CI 2.295-15.087, P=0.000), operative approach (OR=3.143, 95% CI 1.136-8.698, P=0.027), and cement volume injected (OR=1.486, 95% CI 1.119-1.973, P=0.006) were independent risk factors for postoperative cement leakage. CONCLUSIONS This retrospective study showed that dynamic fracture mobility, peripheral vertebrae wall damage, operative approach, and cement volume injected were risk factors for cement leak following PVP and PKP.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Vertebroplastia , Cimentos Ósseos/efeitos adversos , Fraturas por Compressão/etiologia , Fraturas por Compressão/cirurgia , Humanos , Cifoplastia/efeitos adversos , Cifoplastia/métodos , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/cirurgia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/cirurgia , Resultado do Tratamento , Vertebroplastia/efeitos adversos , Vertebroplastia/métodos
3.
Plant Physiol ; 181(2): 714-728, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31420445

RESUMO

Polyacetylenes (PAs) are bioactive, specialized plant defense compounds produced by some species in the eudicot clade campanulids. Early steps of PA biosynthesis are catalyzed by Fatty Acid Desaturase 2 (FAD2). Canonical FAD2s catalyze desaturation, but divergent forms can catalyze hydroxylation, conjugation, acetylenation, and epoxygenation. These alternate reactions give rise to valuable unusual fatty acids, including the precursors to PAs. The extreme functional diversity of FAD2 enzymes and the origin of PA biosynthesis are poorly understood from an evolutionary perspective. We focus here on the evolution of the FAD2 gene family. We uncovered a core eudicot-wide gene duplication event giving rise to two lineages: FAD2-α and FAD2-ß. Independent neofunctionalizations in both lineages have resulted in functionally diverse FAD2-LIKEs involved in unusual fatty acid biosynthesis. We found significantly accelerated rates of molecular evolution in FAD2-LIKEs and use this metric to provide a list of uncharacterized candidates for further exploration of FAD2 functional diversity. FAD2-α has expanded extensively in Asterales and Apiales, two main clades of campanulids, by ancient gene duplications. Here, we detected positive selection in both Asterales and Apiales lineages, which may have enabled the evolution of PA metabolism in campanulids. Together, these findings also imply that yet uncharacterized FAD2-α copies are involved in later steps of PA biosynthesis. This work establishes a robust phylogenetic framework in which to interpret functional data and to direct future research into the origin and evolution of PA metabolism.


Assuntos
Campanulaceae/genética , Evolução Molecular , Ácidos Graxos Dessaturases/genética , Duplicação Gênica , Ácido Linoleico/biossíntese , Ácidos Oleicos/biossíntese , Alcinos , Campanulaceae/metabolismo , Família Multigênica , Filogenia , Polímero Poliacetilênico/metabolismo , Seleção Genética
4.
Eur Phys J E Soft Matter ; 39(5): 57, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27233643

RESUMO

Recent developments in the field of the self-assembly of nanoscale materials such as nanoparticles, nanorods and nanosheets at liquid/liquid interfaces are reviewed. Self-assembly behavior of both biological and synthetic particles is discussed. For biological nanoparticles, the nanoparticle assembly at fluid interfaces provides a simple route for directing nanoparticles into 2D or 3D constructs with hierarchical ordering. The interfacial assembly of single-walled carbon nanotubes (SWCNTs) at liquid interfaces would play a key role in applications such as nanotube fractionation, flexible electronic thin-film fabrication and synthesis of porous SWCNT/polymer composites foams. Liquids can be structured by the jamming of nanoparticle surfactants at fluid interfaces. By controlling the interfacial packing of nanoparticle surfactants using external triggers, a new class of materials can be generated that combines the desirable characteristics of fluids such as rapid transport of energy carriers with the structural stability of a solid.


Assuntos
Nanopartículas/química , Nanotubos de Carbono/química , Polímeros/síntese química , Polímeros/química , Tensoativos/química
5.
Langmuir ; 30(4): 1072-9, 2014 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-24443769

RESUMO

The efficient segregation of water-soluble, acid-functionalized, single-walled carbon nanotubes (SWCNTs) at the oil/water interface was induced by dissolving low-molecular-weight amine-terminated polystyrene (PS-NH2) in the oil phase. Salt-bridge interactions between carboxylic acid groups of SWCNTs and amine groups of PS drove the assembly of SWCNTs at the interface, monitored by pendant drop tensiometry and laser scanning confocal microscopy. The impact of PS end-group functionality, PS and SWCNT concentrations, and the degree of SWCNT acid modification on the interfacial activity was assessed, and a sharp drop in interfacial tension was observed above a critical SWCNT concentration. Interfacial tensions were low enough to support stable oil/water emulsions. Further experiments, including potentiometric titrations and the replacement of SWCNTs by other carboxyl-containing species, demonstrated that the interfacial tension drop reflects the loss of SWCNT charge as the pH falls near/below the intrinsic carboxyl dissociation constant; species lacking multivalent carboxylic acid groups are inactive. The trapped SWCNTs appear to be neither ordered nor oriented.


Assuntos
Nanotubos de Carbono/química , Óleos/química , Água/química , Ácidos Carboxílicos/química , Emulsões , Concentração de Íons de Hidrogênio , Microscopia Confocal , Nanotubos de Carbono/ultraestrutura , Poliestirenos/química
6.
Biosensors (Basel) ; 13(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36671928

RESUMO

Due to the lack of efficient bioelectronic interfaces, the communication between biology and electronics has become a great challenge, especially in constructing bioelectronic sensing. As natural polysaccharide biomaterials, chitosan-based hydrogels exhibit the advantages of flexibility, biocompatibility, mechanical tunability, and stimuli sensitivity, and could serve as an excellent interface for bioelectronic sensors. Based on the fabrication approaches, interaction mechanisms, and bioelectronic communication modalities, this review divided chitosan-based hydrogels into four types, including electrode-based hydrogels, conductive materials conjugated hydrogels, ionically conductive hydrogels, and redox-based hydrogels. To introduce the enhanced performance of bioelectronic sensors, as a complementary alternative, the incorporation of nanoparticles and redox species in chitosan-based hydrogels was discussed. In addition, the multifunctional properties of chitosan-based composite hydrogels enable their applications in biomedicine (e.g., smart skin patches, wood healing, disease diagnosis) and food safety (e.g., electrochemical sensing, smart sensing, artificial bioelectronic tongue, fluorescence sensors, surface-enhanced Raman scattering). We believe that this review will shed light on the future development of chitosan-based biosensing hydrogels for micro-implantable devices and human-machine interactions, as well as potential applications in medicine, food, agriculture, and other fields.


Assuntos
Quitosana , Medicina , Humanos , Quitosana/química , Hidrogéis/química , Materiais Biocompatíveis/química , Inocuidade dos Alimentos
7.
Appl Biochem Biotechnol ; 195(6): 3855-3871, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36251112

RESUMO

Lignocellulose in maize straw includes cellulose, hemicellulose, and lignin, and the degradation of lignocellulose is a complex process in which multiple enzymes are jointly involved. In exploring the co-degradation of a certain substrate by multiple enzymes, different enzymes are combined freely for the achievement of the effective synergism. Additionally, some organic acids and small molecule aromatic compounds can also increase the enzymatic activity of lignin enzymes and improve the degradation rate of lignin. In this study, manganese peroxidase (MnP) from Irpex lacteus (I. lacteus) was heterologously expressed in food-grade Schizosaccharomyces pombe (S. pombe). The multiple enzymes co-fermentation conditions were initially screened by orthogonal tests: 0.5% CaCl2, 1% 10,000 U/g Laccase (Lac), 0.3% MnSO4, and 0.4% glucose oxidase (GOD). It was showed that the lignin degradation rate could reach 65.85% after 3 days of synergistic degradation with the addition of 0.02% Tween-80, 0.5 mM oxalic acid. This indicates that oxalic acid has a promoting effect on the activity of MnP, and the promoting effect is more significant when Tween-80 is complexed with oxalic acid.


Assuntos
Lignina , Zea mays , Lignina/metabolismo , Zea mays/metabolismo , Polissorbatos , Peroxidases/metabolismo , Oxalatos
8.
Clin Interv Aging ; 18: 827-834, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37229150

RESUMO

Background: Recurrent of local kyphosis after percutaneous kyphoplasty (PKP) is rarely reported and discussed. Literatures reported that re-kyphosis is usually a consequence of refractures of augmented or adjacent vertebra. However, whether re-kyphosis should be considered as a complication of refractures and has an impact on clinical efficacy of PKP during follow-up time is unknown. The purpose of this study is to evaluate the related risk factors and clinical significance of the recurrent of local kyphosis in osteoporotic vertebral fracture (OVF) patients without refractures. Patients and Methods: A total of 143 patients who underwent single-level PKP were recruited and assigned into the re-kyphosis group and non-re-kyphosis group. Clinical and radiographic data were collected and compared between the two groups. Then, multivariate logistic regression analyses were conducted to identify the related risk factors. Results: During follow-up, 16 of the 143 patients presented postoperative re-kyphosis. The average local kyphosis angle increased from 11.81±8.60° postoperatively to 25.13±8.91° at the final follow-up which showed a statistically significant difference (p<0.05). Both groups had significant improvements in postoperative visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores compared to their preoperative values (p<0.05). However, in the re-kyphosis group at final follow-up, the VAS and ODI scores showed worsening compared to the postoperative scores. Logistic regression analysis showed that disc-endplate complex injury (OR=17.46, p=0.003); local kyphosis angle correction (OR=1.84, p<0.001); and vertebral height restoration (OR=1.15, p=0.003) were risk factors for re-kyphosis. Conclusion: Re-kyphosis is not rare in patients with osteoporotic vertebral fracture and tends to have an inferior prognosis following PKP surgery. Patients with disc-endplate complex injury and more correction of vertebral height and kyphosis angle are at a higher risk for re-kyphosis after PKP surgery than others.


Assuntos
Fraturas por Compressão , Cifoplastia , Cifose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Humanos , Cifoplastia/efeitos adversos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Fraturas da Coluna Vertebral/etiologia , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/cirurgia , Fraturas por Compressão/etiologia , Estudos Retrospectivos , Cifose/diagnóstico por imagem , Cifose/etiologia , Cifose/cirurgia , Resultado do Tratamento , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/cirurgia , Fraturas por Osteoporose/etiologia , Cimentos Ósseos
9.
J Chromatogr A ; 1602: 178-187, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31301797

RESUMO

A magnetic porous covalent triazine-based organic polymer (M-PCTP) was synthesized by co-precipitation method. The M-PCTP combined both the properties of the PCTP and the magnetism of Fe3O4 nanoparticles, possessing highly porous structure and good magnetism. It was used as a magnetic solid phase extraction (MSPE) adsorbent to extract carbamate pesticides (propoxur, carbaryl, isoprocarb, fenobcarb and diethofencarb) from lemonade and grape juice samples prior to high performance liquid chromatography-mass spectrometric detection. Under the optimal conditions, a good linearity for the real samples was received in the range from 0.10-0.90 to 80.00 ng mL-1 with the correlation coefficients of 0.9882-0.9983. The method recoveries for the five carbamates were 86.3-108.0%. The limits of detection were 0.02-0.20 ng mL-1 for lemonade sample, and 0.04-0.30 ng mL-1 for grape juice sample. The M-PCTP also demonstrated good extraction capabilities for other different kinds of organic compounds including chlorophenols and polycyclic aromatic hydrocarbons.


Assuntos
Carbamatos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Análise de Alimentos/métodos , Espectrometria de Massas , Praguicidas/análise , Extração em Fase Sólida , Sucos de Frutas e Vegetais/análise , Magnetismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Polímeros/química , Porosidade
10.
Neurosci Lett ; 696: 114-120, 2019 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-30579996

RESUMO

BACKGROUND: Detection of α-synuclein (α-syn) in biological fluids such as saliva may serve as potential biomarker of PD. α-syn pertaining to extracellular vesicles (EVs) has been recently studied in plasma, but not in other biological fluids such as saliva. AIM: 1) To investigate the presence of exosomes in PD saliva; 2) to explore the value of α-syn in salivary EVs as potential biomarker in PD. METHODS: Saliva samples were obtained from 74 PD and 60 healthy controls (HCs). The EVs were extracted from saliva by XYCQ EV Enrichment KIT. Western blot and Nanosight 300 were used to validate the existence of exosomes in EVs and to analyze the size of salivary EVs. Salivary EVs α-syn levels, including total α-syn (α-synTotal), oligomeric α-syn (α-synOlig) and phosphorylated-ser129 α-syn (α-synPS129), were measured by Electrochemiluminescence (ECL) assays. Diagnostic value and clinical relevance of salivary EVs α-syn were assessed by Receiver Operator Characteristic (ROC) curve and Spearman correlation. RESULTS: Alix and CD9 positive EVs, representing the presence of exosomes, was detected in PD salivary samples. Size of salivary EVs was about 30-400 nm. The levels of α-synOlig and α-synOlig/α-synTotal in the salivary EVs were higher in PD than in HCs (10.39 ± 1.46 pg/ng vs.1.37 ± 0.24 pg/ng, p<0.001;1.70 ± 0.52 pg/ng vs.0.67 ± 0.26 pg/ng, p<0.001). There was no significant difference in α-synTotal、α-synPS129、 α-synPS129/α-synTotal ratio between PD and HCs (P = 0.723, 0.634, 0.734, respectively). α-synOlig 2.05 pg/ng distinguished PD from HCs with sensitivity 92% and specificity 86%; α-synOlig /α-synTotal 0.18 pg/ng differentiated PD from HCs with sensitivity 81% and specificity 71%. No significant correlation between salivary EVs α-synOlig, α-synOlig/α-synTotal and disease severity was found. CONCLUSIONS: Exosomes are present in PD saliva. The α-synOlig and α-synOlig/α-synTotal ratio in salivary EVs may serve as potential diagnostic biomarkers for PD.


Assuntos
Exossomos/metabolismo , Doença de Parkinson/metabolismo , Saliva/metabolismo , alfa-Sinucleína/metabolismo , Biomarcadores/sangue , Vesículas Extracelulares/metabolismo , Humanos , Curva ROC
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