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Amino acids are essential building blocks for proteins, crucial energy sources for cell survival, and key signaling molecules supporting the resistant growth of tumor cells. In tumor cells, amino acid metabolic reprogramming is characterized by the enhanced uptake of amino acids as well as their aberrant synthesis, breakdown, and transport, leading to immune evasion and malignant progression of tumor cells. This article reviews the altered amino acid metabolism in tumor cells and its impact on tumor microenvironment, and also provides an overview of the current clinical applications of amino acid metabolism. Innovative drugs targeting amino acid metabolism hold great promise for precision and personalized cancer therapy.
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Devices of nanopore sequencing can be highly portable and of low cost. Thus, nanopore sequencing is promising in in-field forensic applications. Previous investigations have demonstrated that nanopore sequencing is feasible for genotyping forensic short tandem repeats (STRs) by using sequencers of Oxford Nanopore Technologies. Recently, Qitan Technology launched a new portable nanopore sequencer and became the second supplier in the world. Here, for the first time, we assess the QNome (QNome-3841) for its accuracy in nanopore sequencing of STRs and compare with MinION (MinION Mk1B). We profile 54 STRs of 21 unrelated individuals and 2800M standard DNA. The overall accuracy for diploid STRs and haploid STRs were 53.5% (378 of 706) and 82.7% (134 of 162), respectively, by using QNome. The accuracies were remarkably lower than those of MinION (diploid STRs, 84.5%; haploid, 90.7%), with a similar amount of sequencing data and identical bioinformatics analysis. Although it was not reliable for diploid STRs typing by using QNome, the haploid STRs were consistently correctly typed. The majority of errors (58.8%) in QNome-based STR typing were one-repeat deviations of repeat units in the error from true allele, related with homopolymers in repeats of STRs.
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In paternity testing, short tandem repeats (STRs) allele mismatches are often detected. Nowadays, polymerase chain reaction- and capillary electrophoresis (CE)-based STR genotyping is the most commonly used method to distinguish alleles based on their length. However, it could not detect alleles of the same size with sequence differences. Massively parallel sequencing (MPS) can determine not only allele sizes but also sequences, which could explain the causes of allele mismatches. Additionally, more types of genetic markers can be detected in a single assay, which increases the discriminatory power and facilitates the analysis of paternity tests. In this study, we analyzed 11 cases with homozygous allele mismatches from routine DNA trio paternity tests using the CE platform. Samples were sequenced using the ForenSeq DNA Signature Prep Kit and the MiSeq FGx Sequencing System. The results show that of the eight father-child mismatch cases and three mother-child mismatch cases, five cases with D5S818 and D8S1179 and one case at D13S317 were classified as non-amplification. The other three cases and two cases could be defined as mutations. This study suggests that MPS-based STR genotyping can provide additional information that allows more accurate interpretation of allelic mismatches in paternity testing.
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Impressões Digitais de DNA , Paternidade , Humanos , Impressões Digitais de DNA/métodos , Alelos , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Repetições de Microssatélites/genética , DNARESUMO
Nanopore sequencing technology has broad application prospects in forensic medicine due to its small size, portability, fast speed, real-time result analysis capabilities, single-molecule sequencing abilities, and simple operation. Here, we demonstrate for the first time that nanopore sequencing platforms can be used to identify individuals in the field. Through scientific and reasonable design, a nanopore MinION MK1B device and other auxiliary devices are integrated into a portable detection box conducive to individual identification at the accident site. Individual identification of 12 samples could be completed within approximately 24 h by jointly detecting 23 short tandem repeat (STR) loci. Through double-blinded experiments, the genotypes of 49 samples were successfully determined, and the accuracy of the STR genotyping was verified by the gold standard. Specifically, the typing success rate for 1150 genotypes was 95.3%, and the accuracy rate was 86.87%. Although this study focused primarily on demonstrating the feasibility of full-process testing, it can be optimistically predicted that further improvements in bioinformatics workflows and nanopore sequencing technology will help enhance the feasibility of Oxford Nanopore Technologies equipment for real-time individual identification at accident sites.
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Repetições de Microssatélites , Sequenciamento por Nanoporos , Humanos , Repetições de Microssatélites/genética , Sequenciamento por Nanoporos/métodos , Genética Forense/métodos , Projetos Piloto , Reprodutibilidade dos Testes , Genótipo , Análise de Sequência de DNA/métodos , Impressões Digitais de DNA/métodos , Desenho de EquipamentoRESUMO
BACKGROUND: Methyltransferase 14 (METTL14) mediated N6-methyladenine (m6A) RNA methylation and progestin and AdipoQ receptor family member 3 (PAQR3) are reported to be involved in diabetic nephropathy (DN) progression. Here, we explored whether the effects of PAQR3 on DN was associated with METTL14-induced m6A and their relationship with macrophage-related exosomes in DN progression. METHODS: Human glomerular endothelial cells (GECs) were incubated in high glucose (HG) condition to mimic DN condition in vitro. Exosomes were isolated from M1 macrophages and co-cultured with GECs. qRT-PCR and western blotting detected the levels of genes and proteins. Cell functions were determined using cell counting kit-8 assay and flow cytometry. ELISA analysis detected inflammatory factors, and oxidative stress was evaluated by measuring reactive oxygen species and malondialdehyde. The m6A modification profile was determined by methylated RNA immunoprecipitation assay and the interaction was verified by dual-luciferase reporter assay. RESULTS: HG elevated PAQR3 expression levels in GECs. PAQR3 silencing reversed HG-induced viability arrest, apoptosis, inflammatory response, and oxidative stress. M1 macrophage co-culture could suppress HG-induced GEC injury. PAQR3 was packaged into M1 macrophage-derived exosomes, and M1 macrophages regulated HG-induced GEC injury by secreting PAQR3 into cells via exosomes. Mechanistically, METTL14 induced PAQR3 m6A modification. METTL14 was enriched in M1 macrophage-derived exosomes. METTL14 knockdown in M1 macrophage-derived exosomes protected GEC from HG-induced viability arrest, apoptosis, inflammation and oxidative stress by regulating PAQR3. CONCLUSION: Exosomal METTL14 derived from M1 macrophages promoted HG-induced apoptosis, inflammation and oxidative stress in GECs by mediating PAQR3 m6A modification.
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Streptococcus spp. are important opportunistic pathogen of bacteremia in both immunocompetent and immunosuppressed patients. A streptococcal strain, designated ST2T, was isolated from the blood specimen of a bacteremic patient. Comparative analyses of 16S rRNA, rpoB and groEL gene sequences demonstrated that the novel strain ST2T is a member of the genus Streptococcus. Based on of 16S rRNA gene sequence similarities, the type strains of Streptococcus (S.) parasanguinis (99.2%), S. ilei (98.8%), S. oralis subsp. oralis (97.6%), S. australis (97.5%) and S. sanguinis (97.5%) were the closest neighbours to strain ST2T. The housekeeping gene sequences (rpoB and groEL) similarities of strain ST2T to these closely related type strains were 80.4-97.4%, respectively. The complete draft genome of strain ST2T consisted of 2,155,906 bp with a G + C content of 42.0%. Strain ST2T has an average nucleotide identity (ANI) value of 94.1 and 81.3% with S. parasanguinis ATCC 15912T and S. ilei I-G2T, respectively. The highest in silico DNA-DNA hybridization value with respect to the closest species S. parasanguinis was 55.6%, below the species cut-off of 70% hybridization. The primary cellular fatty acids of strain ST2T were C16:0, C18:1 ω9c, C18:0 and C14:0. Based on biochemical criteria and molecular genetic evidence, it is proposed that strain ST2T be assigned to a new species of the genus Streptococcus as Streptococcus taoyuanensis sp. nov. The type strain of Streptococcus taoyuanensis is ST2T (=NBRC 115928T = BCRC 81374T) as the type strain.
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Bacteriemia , Composição de Bases , DNA Bacteriano , Filogenia , RNA Ribossômico 16S , Infecções Estreptocócicas , Streptococcus , Bacteriemia/microbiologia , Humanos , RNA Ribossômico 16S/genética , Streptococcus/genética , Streptococcus/isolamento & purificação , Streptococcus/classificação , DNA Bacteriano/genética , Infecções Estreptocócicas/microbiologia , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Genoma Bacteriano , Ácidos Graxos , Hibridização de Ácido Nucleico , Proteínas de Bactérias/genética , MasculinoRESUMO
OBJECTIVE: Staphylococcus aureus (S. aureus), especially Methicillin resistant S. aureus (MRSA), has been disseminated across communities and hospitals, associated with severe infections and organ failure. In order to understand the clinical epidemiological characteristics of S. aureus stains in the First Affiliated Hospital of Wenzhou Medical University in 2018, the prevalence and the drug resistance of S. aureus stains were investigated, for improving the clinical effective prevention and control of S. aureus infection. METHODS: A total of 105 S. aureus isolates were separated from wound infection of inpatients in the First Affiliated Hospital of Wenzhou Medical University in 2018, and the department distributions and drug resistance of the isolates were analyzed. The genotyping homology analysis was conducted through the random amplified polymorphic DNA typing (RAPD-PCR) coupled with NTSYS cluster analysis. RESULTS: Among the 105 strains of S. aureus, 31 isolates were MRSA. The prevalence of MRSA among inpatients in the Departments of Burn, Trauma, Orthopedics, Nephrology and Neurosurgery were 35.48%, 19.35%, 9.68%, 6.45%, and 29.03%, respectively. Among the 105 strains, 35.24% strains were the hospital-acquired infections (HAI) and 64.76% strains were community-acquired infections (CAI). DNA genotyping of the 105 S. aureus strains showed seventeen different groups, most of which were type I, type VII, type IX, and type VII, the others were scattered. CONCLUSION: This study highlights the prevalence of S. aureus strains in the First Affiliated Hospital of Wenzhou Medical University in 2018. The emergence and mutation of the strains should be closely monitored for the prevention and control of the S. aureus infection and transmission in the nosocomial settings.
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Infecções Comunitárias Adquiridas , Infecção Hospitalar , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Centros de Atenção Terciária , Técnica de Amplificação ao Acaso de DNA Polimórfico , Infecções Estafilocócicas/epidemiologia , Infecção Hospitalar/epidemiologia , Infecções Comunitárias Adquiridas/epidemiologia , China/epidemiologia , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologiaRESUMO
To suppress the mid-high-frequency error of small optical tungsten carbide aspheric molds, it is proposed to quickly select the critical process parameters by simulating the residual error after convolution of the tool influence function (TIF). After polishing for 10.47 min by the TIF, two simulation optimizations, RMS and Ra, converge to 9.3 and 5.347 nm, respectively. Their convergence rates are improved by 40% and 7.9%, respectively, compared to ordinary TIF. Then, a faster and more high-quality multi-tool combination smoothing suppression method is proposed, and the corresponding polishing tools are designed. Finally, the global Ra of the aspheric surface converges from 5.9 to 4.5 nm after smoothing for 5.5 min with a disc-shaped polishing tool with a fine microstructure and maintains an excellent low-frequency error (PV 0.0781 µm).
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BACKGROUND: Abnormal maternal lipid concentrations are associated with increased risk of preeclampsia. However, previous studies mainly focused on fasting lipid concentrations, scarce data have been published on the relationship between postprandial triglyceride (TG) concentrations in the second trimester and the risk of preeclampsia. Our aim is to evaluate the potential of triglyceride (TG) concentrations at the time of oral lipid tolerance test (OLTT) measurement in the second trimester to predict preeclampsia and to elucidate the lipid metabolic changes related to these diseases. METHODS: This is a prospective cohort study of Pregnant women at 12-24 weeks of gestation undergone an OLTT in a university affiliated hospital between May 2019 and January 2020. Data were stratified into binaries according to the OLTT results. The receiver operating characteristic (ROC) curve analysis was conducted to determine the optimal cut-off points of TG, HDL-C, LDL-C, sd-LDL, FFA, and BG for predicting preeclampsia. RESULTS: 438 pregnant women were recruited to undergo an OLTT at 12-24 weeks of gestation. Among these, 24 women developed preeclampsia and 414 women remained normotensive. Women who subsequently developed preeclampsia had higher concentrations of 4-h postprandial TG than those who remained normotensive. In the linear logistic regression analyses of potential confounding factors, mid-trimester 4-h postprandial TG concentrations at the time of OLTT measurement were significantly higher in preeclamptic cases than in controls. CONCLUSIONS: Dyslipidemia in the second trimester of pregnancy, particularly postprandial hypertriglyceridemia, appears to be associated with an increased risk of preeclampsia. Mid-trimester 4-h postprandial TG concentration at the time of OLTT measurement may be a potential predictive marker of preeclampsia. Trial registration Data of registration: 2018/10/15. Date of initial participant enrollment: 2019/05/01. Clinical trial identification number: chiCTR1800018884. URL of the registration site: http://www.chictr.org.cn/showproj.aspx?proj=25526 . Data sharing information: The data including individual participant data, detailed study protocols, statistical analysis plans will be shared upon request to the corresponding author.
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Hipertrigliceridemia , Pré-Eclâmpsia , Feminino , Humanos , Período Pós-Prandial , Pré-Eclâmpsia/diagnóstico , Gravidez , Estudos Prospectivos , TriglicerídeosRESUMO
Insulin-like growth factor 2 (IGF2) mRNA binding proteins (IMPs) family belongs to a highly conserved family of RNA-binding proteins (RBPs) and is responsible for regulating RNA processing including localization, translation and stability. Mammalian IMPs (IMP1-3) take part in development, metabolism and tumorigenesis, where they are believed to play a major role in cell growth, metabolism, migration and invasion. IMPs have been identified that are expressed in ovary, placenta and embryo. The up-to-date evidence suggest that IMPs are involved in folliculogenesis, oocyte maturation, embryogenesis, implantation, and placentation. The dysregulation of IMPs not only contributes to carcinogenesis but also disturbs the female reproduction, and may participate in the pathogenesis of reproductive diseases and obstetric syndromes, such as polycystic ovary syndrome (PCOS), pre-eclampsia (PE), gestational diabetes mellitus (GDM) and gynecological tumors. In this review, we summarize the role of IMPs in female reproductive pathophysiology, and hope to provide new insights into the identification of potential therapeutic targets.
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Diabetes Gestacional , Síndrome do Ovário Policístico , Proteínas de Ligação a RNA/metabolismo , Animais , Proteínas de Transporte , Feminino , Humanos , Mamíferos , Gravidez , RNA Mensageiro/genética , ReproduçãoRESUMO
Rutin is one of the most common dietary polyphenols found in vegetables, fruits, and other plants. It is metabolized by the mammalian gut microbiota and absorbed from the intestines, and becomes bioavailable in the form of conjugated metabolites. Rutin exhibits a plethora of bioactive properties, making it an extremely promising phytochemical. Numerous studies demonstrate that rutin can act as a chemotherapeutic and chemopreventive agent, and its anticancer effects can be mediated through the suppression of cell proliferation, the induction of apoptosis or autophagy, and the hindering of angiogenesis and metastasis. Rutin has been found to modulate multiple molecular targets involved in carcinogenesis, such as cell cycle mediators, cellular kinases, inflammatory cytokines, transcription factors, drug transporters, and reactive oxygen species. This review summarizes the natural sources of rutin, its bioavailability, and in particular its potential use as an anticancer agent, with highlighting its anticancer mechanisms as well as molecular targets. Additionally, this review updates the anticancer potential of its analogs, nanoformulations, and metabolites, and discusses relevant safety issues. Overall, rutin is a promising natural dietary compound with promising anticancer potential and can be widely used in functional foods, dietary supplements, and pharmaceuticals for the prevention and management of cancer.
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Antineoplásicos , Neoplasias , Animais , Antineoplásicos/uso terapêutico , Antioxidantes/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Rutina/uso terapêuticoRESUMO
PURPOSE: Work-related ocular trauma remains the leading cause of unilateral visual impairment worldwide. Many preventable work-related ocular injuries continue to occur, even at home. This study describes the characteristics, surgical techniques, and prognostic factors of lawn trimmer-related open-globe injuries in eastern Taiwan. METHODS: This was a retrospective, consecutive case series study. Slit-lamp biomicroscopy, dilated fundoscopy, and orbital computed tomography (CT) images were collected. RESULTS: Twenty-six eyes of 26 patients were enrolled in the study. Fifteen patients (57.7%) had an intraocular foreign body (IOFB). The IOFB was metallic in 13 cases and glass and stone in the other 2 cases. Seven IOFBs (46.7%) were retained in the anterior chamber, 7 (46.7%) in the posterior segment, and 1 (6.7%) in the intraconal space. Univariate analysis showed that the presence of IOFB trended toward the development of endophthalmitis; however, this was not statistically significant (hazard ratio, 2.25; 95% confidence interval 0.35-14.61; P = 0.658). Eleven patients had metallic IOFBs noted on CT scans with metal artifacts, whereas two patients had small metallic IOFBs without metal artifacts. One patient had a glass IOFB mimicking metal artifacts on the CT scan. In one case, CT failed to reveal the IOFB, and an intralenticular metallic foreign body was incidentally found intraoperatively. CONCLUSION: Our study provides a broad characterization of lawn trimmer-related open-globe injuries. The informative and diverse findings of IOFBs on CT scans will help clinicians detect and recognize IOFBs more precisely and perform the surgery without causing further damage.
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Corpos Estranhos no Olho , Ferimentos Oculares Penetrantes , Corpos Estranhos no Olho/diagnóstico , Corpos Estranhos no Olho/etiologia , Corpos Estranhos no Olho/cirurgia , Ferimentos Oculares Penetrantes/diagnóstico , Ferimentos Oculares Penetrantes/epidemiologia , Ferimentos Oculares Penetrantes/etiologia , Humanos , Estudos Retrospectivos , Taiwan/epidemiologia , Acuidade VisualRESUMO
Twelve polyphenols from three distinct families (dihydroflavonols, flavan-3-ols, and flavanones) were studied as potential substrates of anthocyanidin synthase from Vitis vinifera (VvANS). Only flavan-3-ols of (2R,3S) configuration having either a catechol or gallol group on ring B are accepted as substrates. Only dihydroflavonols of (2R,3R) configuration are accepted as substrates, but a catechol or gallol group is not mandatory. Flavanones are not substrates of VvANS. HPLC and MS/MS analyses of the enzymatic products showed that the VvANS-catalyzed oxidative transformation of (+)-dihydroflavonols, such as dihydroquercetin, dihydrokaempferol and dihydromyricetin, leads only to the corresponding flavonols. Among the flavan-3-ols recognized as substrates, (+)-gallocatechin was only transformed into delphinidin by VvANS, whereas (+)-catechin was transformed into three products, including two major products that were an ascorbate-cyanidin adduct and a dimer of oxidized catechin, and a minor product that was cyanidin. Data from real-time MS monitoring of the enzymatic transformation of (+)-catechin suggest that its products are all derived from the initial C3-hydroxylation intermediate, i.e., a 3,3-gem-diol, and their most likely formation mechanism is discussed.
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Flavonóis/metabolismo , Oxigenases/metabolismo , Proteínas de Plantas/metabolismo , Vitis/metabolismo , Oxirredução , Polifenóis/metabolismo , Especificidade por SubstratoRESUMO
BACKGROUND: Human Ectopic Pregnancy (hEP) is the second most common cause of pregnancy-related deaths in the first trimester. Without timely detection, EPs can lead to an increased rate of infertility and an elevated risk for future tubal EPs. In addition, most studies in the field focus on the effect of the fallopian tube (maternal factors) and ignore epigenetic changes in genes and proteins of the embryo, which may also cause EPs. Therefore, the present study hypothesized that embryos also play an important role in the development of EP. The study also speculated that DNA methylation is associated with ectopic pregnancy. Consequently, the effects of DNA methylation on the occurrence and development of ectopic pregnancy were investigated. Moreover, genome-wide DNA methylation of chorionic tissue from ectopic and intrauterine pregnancies was detected using Illumina HumanMethylation450 arrays. RESULTS: Forty-three hypermethylated genes involved in the regulation of adhesion as well as gene transcription and translation were identified. Furthermore, the PPI network showed that AMOTL1, SDR42E1, CAMTA1, PIP5K1C, KIAA1614, TSTD1 and DNER may play important roles in the occurrence and development of ectopic pregnancy. In addition, SDR42E1, CAMTA1 and TSTD1 displayed higher levels of methylation in ectopic pregnancy while PIP5K1C and DNER showed low degrees of methylation. CONCLUSIONS: The study reveals that abnormal increase in methylation may be an early indicator or an inducer of ectopic pregnancy. In addition, AMOTL1, SDR42E1, CAMTA1, PIP5K1C, KIAA1614, TSTD1 and DNER might play important roles in the occurrence and development of ectopic pregnancy. However, the specific molecular mechanisms are still unclear and require further studies.
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Córion/metabolismo , Metilação de DNA/fisiologia , Redes Reguladoras de Genes/fisiologia , Estudo de Associação Genômica Ampla/métodos , Gravidez Ectópica/genética , Gravidez Ectópica/metabolismo , Córion/patologia , Feminino , Humanos , Infertilidade/diagnóstico , Infertilidade/genética , Infertilidade/metabolismo , Gravidez , Gravidez Ectópica/diagnósticoRESUMO
The MinION nanopore sequencing device (Oxford Nanopore Technologies, Oxford, UK) is the smallest commercially available sequencer and can be used outside of conventional laboratories. The use of the MinION for forensic applications, however, is hindered by the high error rate of nanopore sequencing. One approach to solving this problem is to identify forensic genetic markers that can consistently be typed correctly based on nanopore sequencing. In this pilot study, we explored the use of nanopore sequencing for single nucleotide polymorphism (SNP) and short tandem repeat (STR) profiling using Verogen's (San Diego, CA, USA) ForenSeq DNA Signature Prep Kit. Thirty single-contributor samples and DNA standard material 2800 M were genotyped using the Illumina (San Diego, CA, USA) MiSeq FGx and MinION (with R9.4.1 flow cells) devices. With an optimized cutoff for allelic imbalance, all 94 identity-informative SNP loci could be genotyped reliably using the MinION device, with an overall accuracy of 99.958% (1 error among 2926 genotypes). STR typing was notably error prone, and its accuracy was locus dependent. We developed a custom-made bioinformatics workflow, and finally selected 13 autosomal STRs, 14 Y-STRs, and 4 X-STRs showing high consistency between nanopore and Illumina sequencing among the tested samples. These SNP and STR loci could be candidates for panel design for forensic analysis based on nanopore sequencing.
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Técnicas de Genotipagem , Repetições de Microssatélites , Sequenciamento por Nanoporos/métodos , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA/métodos , Marcadores Genéticos , Humanos , Projetos PilotoRESUMO
A new structural type for melt cast materials was designed by linking nitrotetrazole ring with 1,2,4-oxadiazole through a N-CH2-C bridge for the first time. Three N-CH2-C linkage bridged energetic compounds, including 3-((5-nitro-2H-tetrazol-2-yl) methyl)-1,2,4-oxadiazole (NTOM), 3-((5-nitro-2H-tetrazol-2-yl)methyl)-5-(trifluoromethyl)-1,2,4 -oxadiazole (NTOF) and 3-((5-nitro-2H-tetrazol-2-yl)methyl)-5-amine-1,2,4-oxadiazole (NTOA), were designed and synthesized through a two-step reaction by using 2-(5-nitro-2H-tetrazole -2-yl)acetonitrile as the starting material. The synthesized compounds were fully characterized by NMR (1H, 13C), IR spectroscopy and elemental analysis. The single crystals of NTOM, NTOF and NTOA were successfully obtained and investigated by single-crystal X-ray diffraction. The thermal stabilities of these compounds were evaluated by DSC-TG measurements, and their apparent activation energies were calculated by Kissinger and Ozawa methods. The crystal densities of the three compounds were between 1.66 g/cm3 (NTOA) and 1.87 g/cm3 (NTOF). The impact and friction sensitivities were measured by standard BAM fall-hammer techniques, and their detonation performances were computed using the EXPLO 5 (v. 6.04) program. The detonation velocities of the three compounds are between 7271 m/s (NTOF) and 7909 m/s (NTOM). The impact sensitivities are >40 J, and the friction sensitivities are >360 N. NTOM, NTOF and NTOA are thermally stable, with decomposition points > 240 °C. The melting points of NTOM and NTOF are 82.6 °C and 71.7 °C, respectively. Hence, they possess potential to be used as melt cast materials with good thermal stabilities and better detonation performances than TNT.
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Short tandem repeat (STR) markers have been widely used in forensic paternity testing and individual identification, but the STR mutation might impact on the forensic result interpretation. Importantly, the STR mutation rate was underestimated due to ignoring the "hidden" mutation phenomenon in most similar studies. Considering this, we use Slooten and Ricciardi's restricted mutation model based on big data to obtain more accurate mutation rates for each marker. In this paper, the mutations of 20 autosomal STRs loci (D3S1358, D1S1656, D13S317, Penta E, D16S539, D18S51, D2S1338, CSF1PO, Penta D, TH01, vWA, D21S11, D6S1043, D7S820, D5S818, TPOX, D8S1179, D12S391, D19S433, and FGA; The restricted model does not include the correction factor of D6S1043, this paper calculates remaining 19 STR loci mutation rates) were investigated in 28,313 (Total: 78,739 individuals) confirmed parentage-testing cases in Chinese Han population. As a result, total 1665 mutations were found in all loci, including 1614 one-steps, 34 two-steps, 8 three-steps, and 9 nonintegral mutations. The loci-specific average mutation rates ranged from 0.00007700 (TPOX) to 0.00459050 (FGA) in trio's and 0.00000000 (TPOX) to 0.00344850 (FGA) in duo's. We analyzed the relationship between mutation rates of the apparent and actual, the trio's and duo's, the paternal and maternal, respectively. The results demonstrated that the actual mutation rates are more than the apparent mostly, and the values of µ1"/µ2"(apparent) are also greater than µ1/µ2 (actual) commonly (µ1", µ1; µ2", µ2 are the mutation rates of one-step and two-step). Therefore, the "hidden" mutations are identified. In addition, the mutations rates of trio's and duo's, the paternal and maternal, exhibit significant difference. Next, those mutation data are used to do a comparison with the studies of other Han populations in China, which present the temporal and regional disparities. Due to the large sample size, some rare mutation events, such as monozygotic (MZ) mutation and "fake four-step mutation", are also reported in this study. In conclusion, the estimation values of actual mutations are obtained based on big data, they can not only provide basic data for the Chinese forensic DNA and population genetics databases, but also have important significance for the development of forensic individual identification, paternity testing and genetics research.
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Big Data , Repetições de Microssatélites , Frequência do Gene , Genética Populacional , Humanos , Repetições de Microssatélites/genética , Mutação , Taxa de MutaçãoRESUMO
Skeletal remains encountered frequently in forensic applications are a challenging specimen, since their DNA is usually degraded due to harsh conditions, limiting the utilization of skeletal DNA. Forensic scientists have tried various methods to extract DNA from skeletal remains of low quantity and poor quality or improve detecting technology for more information from compromised DNA. Compared with traditional capillary electrophoresis (CE), massively parallel sequencing (MPS) is more sensitive to shorter fragments, able to detect allele sequences for variations from core motif or flanking regions, and able to detect more markers with a higher discrimination power. In this study, short tandem repeats (STR) and single nucleotide polymorphisms (SNP) from 35 human skeletons were genotyped by MPS platform, and CE method was also used to perform STR genotyping. The results indicated that the detection rates reached 100.00% in 16 of 35 samples with MPS method, while the same 100.00% was reached in only 9 samples with CE. The success rates of MPS were also higher than that of CE method in shared 21 loci (excluding Y-indel, DYS391, and SE33), especially in loci detected by MPS method only. Besides, all SNPs (124 and 90 SNPs in males and females) were detected in 18 samples of 35 samples by MPS method. Some intra-allelic sequence variants were observed in eight loci (D21S11, D8S1179, D5S2800, D3S1358, vWA, D2S1338, D1S1656, D12S391) using MPS technology. Interestingly, there is a sample showing genotyping disagreement in FGA locus. The clone sequencing verified that a "T" deletion discovered in flanking sequence of FGA led to wrong genotyping on Ampliseq Converge. Our results indicated that MPS could be adopted in qualified labs as a supplementary when the DNA of skeletal remains are hard to identify.
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Restos Mortais , Impressões Digitais de DNA/métodos , DNA/análise , DNA/isolamento & purificação , Eletroforese Capilar , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Alelos , Feminino , Loci Gênicos , Genótipo , Técnicas de Genotipagem , Humanos , Masculino , Repetições de Microssatélites , Polimorfismo de Nucleotídeo ÚnicoRESUMO
The name of an author was misspelled. The correct spelling is "Linlin Gao" instead of Linin Gao.
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In this study, the efficiency of microwave-assisted hydro-distillation (MAHD) to extract essential oil from Cinnamomum camphora leaf, and the recovery of polyphenols from extract fluid were investigated. The effects of microwave power, liquid-to-material ratio, and extraction time on the extraction efficiency were studied by a single factor test as well as the response surface methodology (RSM) based on the central composite design method. The optimal extraction conditions were a microwave power of 786.27 W, liquid-to-material ratio of 7.47:1 mL/g, and extraction time of 35.57 min. The yield of essential oil was 3.26 ± 0.05% (w/w), and the recovery of polyphenols was 4.97 ± 0.02 mg gallic acid equivalent/g dry weight under the optimal conditions. Furthermore, the comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOFMS) was used to characterize the essential oils of fresh and fallen leaves, and 159 individual compounds were tentatively identified, accounting for more than 89.68 and 87.88% of the total contents, respectively. The main ingredients include sabinene, l-ß-pinene, ß-myrcene, α-terpineol, 3-heptanone, and ß-thujene, as well as δ-terpineol and 3-heptanone, which were first identified in C. camphora essential oil. In conclusion, the MAHD method could extract essential oil from C. camphora with high efficiency, and the polyphenols could be obtained from the extract fluid at the same time, improving the utilization of C. camphora leaf.