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In this article, chiral covalent organic framework core-shell composite CCOF-TpPa-Py@SiO2 was facilely synthesized by induction at room temperature. The CCOF-TpPa-Py@SiO2 core-shell composite was used as a chiral stationary phase for the separation of the racemates by high-performance liquid chromatography, which exhibits good separation performance for chiral compounds including ketones, alcohols, esters, epoxides, carboxylic acids, amides, and amines. The effects of analyte injection mass on the enantioseparation were studied. The reproducibility and stability of the CCOF-TpPa-Py@SiO2 chiral column were explored. The intra-day (n = 5), inter-day (n = 5), and inter-column (n = 3) relative standard deviations for the migration times and resolution of benzoin were 0.32%-0.54%, 0.45%-0.61%, and 1.21%-1.53%, respectively. In addition, the chiral separation ability of the CCOF-TpPa-Py@SiO2 chiral column (column A) was compared with that of the MDI-ß-CD-Modified COF@SiO2 (column B) as well as a commercial chiral column (Chiralpak AD-H). The chiral recognition ability of column A is complementary to that of column B and AD-H column. The resolution mechanism of CCOF-TpPa-Py@SiO2 stationary phase towards chiral analyte was explored. Hence, the synthesis of CCOF-TpPa-Py@SiO2 core-shell composite by induction at room temperature as chiral stationary phases for chromatographic separation has important research potential and application prospects.
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Macrocycles play vital roles in supramolecular chemistry and chromatography. 1,1'-Bi-2-naphthol (BINOL)-based chiral polyimine macrocycles are an emerging class of chiral macrocycles that can be constructed by one-step aldehyde-amine condensation of BINOL derivatives with other building blocks. These macrocycles exhibit good characteristics, such as facile preparation, rigid cyclic structures, multiple chiral centers, and defined molecular cavities, that make them good candidates as new chiral recognition materials for chromatographic enantioseparations. In this study, a BINOL-based [2+2] chiral polyimine macrocycle was synthesized by one-step condensation of enantiopure (S)-2,2'-dihydroxy-[1,1'-binaphthalene]-3,3'-dicarboxaldehyde with (1R,2R)-1,2-diaminocyclohexane. The product was modified with 5-bromo-1-pentene and then attached to thiolated silica using click chemistry to construct a new chiral stationary phase (CSP). The enantioselectivity of the new CSP was explored by separating various racemates under normal phase (NP) and reversed phase (RP) high performance liquid chromatography (HPLC). Thirteen racemates and eight racemates were enantioseparated under the two separation modes, respectively, including chiral alcohols, phenols, esters, ketones, amines, and organic acids. Among them, nine racemates achieved baseline separation under NP-HPLC and seven racemates achieved baseline separation under RP-HPLC. High resolution separation was observed with benzoin (Rs = 5.10), epinephrine (Rs = 4.98), 3-benzyloxy-1,2-propanediol (Rs = 4.42), and 4,4'-dimethylbenzoin (Rs = 4.52) in NP-HPLC, and with 4-methylbenzhydrol (Rs = 4.72), benzoin ethyl ether (Rs = 3.79), 1-phenyl-1-pentanol (Rs = 3.68), and 1-(3-bromophenyl)ethanol (Rs = 3.60) in RP-HPLC. Interestingly, the CSP complemented Chiralcel OD-H, Chiralpak AD-H, and CYCLOBOND I 2000 RSP columns for resolution of these test racemates, separating several racemic compounds that could not be well separated by the three commercially available columns. The influences of injected sample amount on separation were also evaluated. It was found that the column exhibited excellent stability and reproducibility after hundreds of injections, and the relative standard deviations (n = 5) of the retention time and resolution were less than 0.49% and 0.69%, respectively. This study indicates that the BINOL-based chiral macrocycle has great potential for HPLC enantioseparation.
Assuntos
Compostos Macrocíclicos , Naftóis , Dióxido de Silício , Cromatografia Líquida de Alta Pressão/métodos , Estereoisomerismo , Naftóis/química , Naftóis/isolamento & purificação , Compostos Macrocíclicos/química , Compostos Macrocíclicos/isolamento & purificação , Dióxido de Silício/químicaRESUMO
Macrocyclic compounds such as crown ethers and cyclodextrins play an important role in the field of chromatography and show excellent separation performance. The design of simple and convenient methods for the efficient synthesis of novel chiral macrocycles for chromatographic separation is of great significance. In this work, a novel chiral polyimine macrocycle (PIMC) was designed and synthesized by the simply one-step reaction of 2,6-diformyl-4-tert-butylphenol with (S)-(-)-1,2-propanediamine. Then, it was bonded onto silica by the thiol-ene click reaction to construct a new chiral stationary phase (CSP) for high-performance liquid chromatography (HPLC). The chiral separation performance of the proposed CSP was examined by separating various racemates in the normal-phase (NP) and reversed-phase (RP) HPLC. In total, twelve and nine racemates, including ethers, esters, amines, alcohols, organic acids, ketones, and epoxides, were separated to varying degrees via NP-HPLC and RP-HPLC, respectively, Moreover, the CSP offered good chiral separation complementarity to Chiralcel OD-H and Chiralpak AD-H columns for resolution of these test racemates, and it can separate several racemic compounds that either cannot be separated or cannot be separated well be separated by the two commercially available columns. After the column was used for hundreds of injections, the relative standard deviations of the retention time and resolution were below 0.56 % and 0.45 %, respectively, showing the good reproducibility and stability of the CSP. This study provides a simple and convenient approach to synthesize a novel chiral macrocycle and CSP and also indicates the broad application prospects of such chiral PIMCs in HPLC chiral separation.
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Porous organic cages (POCs) are a new type of molecular material. The well-defined cavities, abundant host-guest recognition ability, and good solubility of POCs render them attractive for use in various fields such as molecular recognition, gas adsorption, molecular containers, sensing, catalysis, chromatographic separation. In this study, a chiral POC (CPOC) was synthesized via the Schiff base condensation of 4,4',4â³,4â³'-(ethene-1,1,2,2-tetrayl)tetrabenzaldehyde with (R,R)-1,2-cyclohexanediamine. CPOC was characterized using nuclear magnetic resonance (NMR) spectroscopy, Fourier transform-infrared (FT-IR) spectroscopy, mass spectroscopy (MS), and thermogravimetric analysis (TGA). The FT-IR spectrum of CPOC showed a strong peak at 1638 cm-1, which was attributed to imine (-C=N-) absorption, as well as absorption peaks at 2928 and 2856 cm-1, which were attributed to the stretching vibrations of -CH2- and -CH-, respectively. MS analysis of CPOC revealed peaks at m/z=1801.9797, m/z=901.9914, and m/z=601.6631, corresponding to [M+H]+, [M+2H]2+, and [M+3H]3+, respectively, and indicating a molecular formula of CPOC (C126H120N12). The TGA curve of CPOC indicated high thermal stability up to 360 â; thus, the material is suitable for use as a stationary phase for gas chromatography (GC). CPOC was coated on the inner wall of a capillary column using the static coating method to prepare a GC column. Scanning electron microscopy (SEM) was used to characterize the coating condition of the fabricated column. The SEM images showed that the column had a uniform coating with a thickness of approximately 200 nm. Column efficiency was determined to be 3500 plates/m using n-dodecane as a target at 120 â. The polarity of the CPOC stationary phase was evaluated using McReynolds constants, which were measured using benzene, 1-nitropropane, 2-pentanone, pyridine, and 1-butanol as probe molecules at 120 â. The average McReynolds constant was 152, indicating that CPOC is a moderately polar stationary phase. The ability of the column to separate organic mixtures, isomers, and chiral compounds was subsequently investigated. All components of the four organic mixtures (n-alkanes, aromatics, n-alcohols, and Grob mixtures) tested achieved baseline separation on the column. In addition, nine positional isomers of disubstituted benzenes were well separated, and seven (o,m,p-nitrotoluene, o,m,p-nitrochlorobenzene, o,m,p-nitrobromobenzene, o,m,p-bromotoluene, o,m,p-dichlorobenzene, o,m,p-chloroaniline, and o,m,p-bromoaniline) achieved baseline separation. Some polar and apolar structural isomers, such as pentanol, dimethylphenol, dimethylaniline, butanol, and C9 aromatic hydrocarbon isomers, were also well separated on the column. Five cis/trans-isomers (nerol/geraniol, cis/trans-1,3-dichloropropene, cis/trans-1,2,3-trichloropropene, cis/trans-citral, and cis/trans-decahydronaphthalene) were baseline-separated on the column. More importantly, the column successfully separated 12 chiral compounds, indicating good chiral separation ability. Among these chiral compounds, five (ethyl 3-hydroxybutyrate, a valine derivative, a glutamic acid derivative, 1,2-butanediol diacetate, and 1,2-epoxybutane) achieved baseline separation. Six of these chiral compounds (ethyl 3-hydroxybutyrate, the valine derivative, the glutamic acid derivative, 1,2-epoxybutane, epichlorohydrin, and epibromohydrin) could not be separated on a ß-DEX 120 column but were well separated on the developed column. Moreover, the separation efficiency of 1,2-butanediol diacetate and the isoleucine derivative on this column was better than that on the ß-DEX 120 column. Separation of the glutamic acid derivative and o,m,p-nitrotoluene was performed before and after the column was used for repeated injections to explore its repeatability. The retention times and selectivity observed after 80, 160, and 500 injections were nearly unchanged compared with those obtained following the first use of the column, indicating that the column has good repeatability. The column was conditioned at 280 â for a certain period to examine its thermal stability. Separation of 3-hydroxybutyrate and o,m,p-nitrochlorobenzene after the column was conditioned at 280 â for 2, 4, or 8 h revealed no obvious changes compared with the first use of the column, indicating that the column had good thermal stability. Thus, CPOC is a stationary phase with good application potential for GC.
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OBJECTIVE: To compare the clinical value of multi-slice spiral computed tomography (MSCT) low-dose three-dimensional reconstruction and traditional X-ray in the auxiliary diagnosis of distal radius epiphyseal injury in children. METHODS: A retrospective analysis was performed on 105 children with distal radius bone scale injury (classified by Salter-Harris classification) admitted from March 2020 to June 2022. All children underwent MSCT three-dimensional reconstruction examination and traditional X-ray examination. The detection rate of epiphyseal injury of the distal radius was compared, along with the resolution, sensitivity and specificity. The image clarity and display degree of bone structure were analyzed. The radiation dose-related indicators and the time required for diagnosis were compared. RESULTS: The detection rate and diagnostic accuracy of MSCT (100%, 92.38%) was significantly higher than that of X-ray (76.19%, 64.76%). In terms of radiation dose index, the volume dose index CTDI of MSCT ranged from 1-5 mGy while the X-ray group ranged from 5-10 mGy. The dose length product (DLP) value of the MSCT group was lower than in the X-ray group (20-100 mGy·cm vs. 50-150 mGy·cm). The diagnostic scan time for MSCT was shorter than that of conventional X-ray. The acceptance rate with MSCT was 99%, significantly higher than that with conventional X-ray (85%). CONCLUSIONS: Low-dose three-dimensional reconstruction of MSCT in the diagnosis of epiphyseal injury of distal radius in children shows significant advantages over traditional CT in the detection rate, diagnostic accuracy, postoperative reduction quality evaluation, and radiation dose.
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A novel CCOF core-shell composite material (S)-DTP-COF@SiO2 was prepared via asymmetric catalytic and in situ growth strategy. The prepared (S)-DTP-COF@SiO2 was utilized as separation medium for HPLC enantioseparation using normal-phase and reversed-phase chromatographic modes, which displays excellent chiral separation performance for alcohols, esters, ketones, and epoxides, etc. Compared with chiral commercial chromatographic columns (Chiralpak AD-H and Chiralcel OD-H columns) and some previously reported chiral CCOF@SiO2 (CC-MP CCTF@SiO2 and MDI-ß-CD-modified COF@SiO2)-packed columns, there are 4, 3, 13, and 15 tested racemic compounds that could not be resolved on the Chiralpak AD-H column, Chiralcel OD-H column, CC-MP CCTF@SiO2 column, and MDI-ß-CD-modified COF@SiO2 column, respectively, which indicates that the resolution effect of (S)-DTP-COF@SiO2-packed column can be complementary to the other ones. The effects of the analyte mass, column temperature, and mobile phase composition on the enantiomeric separation were investigated. The chiral column exhibits good reproducibility after multiple consecutive injections. The RSDs (n = 5) of the peak area and retention time were less than 1.5% for repetitive separation of 2-methoxy-2-phenylethanol and 1-phenyl-1-pentanol. The chiral core-shell composite (S)-DTP-COF@SiO2 exhibited good enantiomeric separation performance, which not only demonstrates its potential as a novel CSP material in HPLC but also expands the range of applications for chiral COFs.
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Altered transcriptional and epigenetic regulation of brain cell types may contribute to cognitive changes with advanced age. Using single-nucleus multi-omic DNA methylation and transcriptome sequencing (snmCT-seq) in frontal cortex from young adult and aged donors, we found widespread age- and sex-related variation in specific neuron types. The proportion of inhibitory SST- and VIP-expressing neurons was reduced in aged donors. Excitatory neurons had more profound age-related changes in their gene expression and DNA methylation than inhibitory cells. Hundreds of genes involved in synaptic activity, including EGR1, were less expressed in aged adults. Genes located in subtelomeric regions increased their expression with age and correlated with reduced telomere length. We further mapped cell-type-specific sex differences in gene expression and X-inactivation escape genes. Multi-omic single-nucleus epigenomes and transcriptomes provide new insight into the effects of age and sex on human neurons.
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Metilação de DNA , Neurônios , Humanos , Neurônios/metabolismo , Neurônios/fisiologia , Feminino , Masculino , Adulto , Idoso , Adulto Jovem , Envelhecimento/fisiologia , Envelhecimento/genética , Caracteres Sexuais , Pessoa de Meia-Idade , Epigênese Genética , Transcriptoma , Fatores Etários , Idoso de 80 Anos ou mais , Lobo Frontal/metabolismo , Lobo Frontal/citologia , Inativação do Cromossomo X/genética , Córtex Cerebral/citologia , Córtex Cerebral/metabolismoRESUMO
Metal organic cages (MOCs), as an emerging discrete supramolecular compounds, have received widespread attention in separation, biomedicine, gas capture, catalysis, and molecular recognition due to their porosity, adjustability and stability. Herein, we present a new chiral MOC FeII4L4 coated capillary column prepared for gas chromatographic (GC) separation of different types of organic compounds, including n-alkanes, n-alcohols, alkylbenzenes, isomers, especially for racemic compounds. There are 20 different kinds of racemates (e.g., alcohols, ethers, epoxides, esters, alkenes, and aldehydes) were well resolved on the FeII4L4 chiral column and a maximum resolution value for 1-phenyl-1-propanol reaches 6.17. The FeII4L4 coated column exhibited high column efficiency (3100 plates m-1 for n-dodecane) and good enantiomeric resolution complementary to that of a commercial ß-DEX 120 column and the previously reported chiral MOC [Fe4L6] (ClO4)8 coated column. The relative standard deviation (RSDs) of the peak area and retention time of glycidol and nitrotoluene were below 1.2 %. This study reveals that chiral MOCs have good application prospects in chromatographic separation.
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Adding synthetic nucleotides to DNA increases the linear information density of DNA molecules. Here we report that it also can increase the diversity of their three-dimensional folds. Specifically, an additional nucleotide (dZ, with a 5-nitro-6-aminopyridone nucleobase), placed at twelve sites in a 23-nucleotides-long DNA strand, creates a fairly stable unimolecular structure (that is, the folded Z-motif, or fZ-motif) that melts at 66.5 °C at pH 8.5. Spectroscopic, gel and two-dimensional NMR analyses show that the folded Z-motif is held together by six reverse skinny dZ-:dZ base pairs, analogous to the crystal structure of the free heterocycle. Fluorescence tagging shows that the dZ-:dZ pairs join parallel strands in a four-stranded compact down-up-down-up fold. These have two possible structures: one with intercalated dZ-:dZ base pairs, the second without intercalation. The intercalated structure would resemble the i-motif formed by dC:dC+-reversed pairing at pH ≤ 6.5. This fZ-motif may therefore help DNA form compact structures needed for binding and catalysis.
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PURPOSE: To compare the morphometry of paraspinal muscles in patients with degenerative spondylolisthesis (DS), isthmic spondylolisthesis (IS), and healthy individuals. METHODS: Thirty-seven pairs of DS patients were selected using propensity score matching with IS patients, while 37 healthy individuals matched for age, sex, and BMI were selected as controls. The relative cross-sectional area (rCSA), and relative functional cross-sectional area (rfCSA) of paraspinal muscles were measured, and the degree of fatty infiltration (FI) was calculated. Based on occupational differences, the patients were also divided into worker and farmer groups, and the same measurements were taken on them. RESULTS: At the L3/L4 level, the multifidus (MF) FI was greater in the DS and IS groups than in the control group, the erector spinae (ES) rfCSA was higher in the IS group than in the DS and control groups. At the L4/L5 level, MF rfCSA was smaller in the DS and IS groups than in the control group; ES rfCSA was higher in the IS group than in the DS and control groups. At the L5/S1 level, MF rfCSA was smaller in the DS and IS groups than in the control group; ES rfCSA was higher in the IS group than in the DS group. At the L3/L4, L4/L5 level, MF rfCSA were higher in the worker group than in the farmer group (p < 0.05). CONCLUSION: The morphological changes in paraspinal muscles in patients with DS were dominated by selective atrophy of the MF, while in patients with IS, the morphological changes in paraspinal muscle showed selective atrophy of the MF accompanied by compensatory hypertrophy of the ES. The surgeon should consider the morphological differences in paraspinal muscle between different types of lumbar spondylolisthesis when establishing the appropriate surgical program.
Assuntos
Vértebras Lombares , Músculos Paraespinais , Pontuação de Propensão , Espondilolistese , Humanos , Espondilolistese/diagnóstico por imagem , Espondilolistese/patologia , Músculos Paraespinais/patologia , Músculos Paraespinais/diagnóstico por imagem , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Adulto , Estudos de Casos e Controles , Imageamento por Ressonância MagnéticaRESUMO
With just four building blocks, low sequence information density, few functional groups, poor control over folding, and difficulties in forming compact folds, natural DNA and RNA have been disappointing platforms from which to evolve receptors, ligands, and catalysts. Accordingly, synthetic biology has created "artificially expanded genetic information systems" (AEGIS) to add nucleotides, functionality, and information density. With the expected improvements seen in AegisBodies and AegisZymes, the task for synthetic biologists shifts to developing for expanded DNA the same analytical tools available to natural DNA. Here we report one of these, an enzyme-assisted sequencing of expanded genetic alphabet (ESEGA) method to sequence six-letter AEGIS DNA. We show how ESEGA analyses this DNA at single base resolution, and applies it to optimized conditions for six-nucleotide PCR, assessing the fidelity of various DNA polymerases, and extending this to AEGIS components with functional groups. This supports the renewed exploitation of expanded DNA alphabets in biotechnology.
Assuntos
DNA , Sequenciamento de Nucleotídeos em Larga Escala , Sequenciamento de Nucleotídeos em Larga Escala/métodos , DNA/genética , DNA/metabolismo , Biologia Sintética/métodos , DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/genética , Reação em Cadeia da Polimerase/métodos , Sequência de Bases , Análise de Sequência de DNA/métodosRESUMO
In this study, we have synthesised a chiral l-hyp-Ni/Fe@SiO2 composite as a chiral stationary phase (CSP) for high-performance liquid chromatography (HPLC) for the first time. This was achieved by coating two-dimensional (2D) chiral metal-organic framework nanosheets (MONs) l-hyp-Ni/Fe onto the surface of activated SiO2 microspheres using the "wrapped in net" method. The separation efficiency of the l-hyp-Ni/Fe chromatographic column was systematically evaluated in normal-phase HPLC (NP-HPLC) and reversed-phase HPLC (RP-HPLC) configurations, employing various racemates as analytes. The findings revealed that 16 chiral compounds were separated using NP-HPLC, and five were separated using RP-HPLC, encompassing alcohols, amines, ketones, esters, alkanes, ethers, amino acids and sulfoxides. Notably, the resolution (Rs) of nine chiral compounds exceeded 1.5, indicating baseline separation. Furthermore, the resolution performance of the l-hyp-Ni/Fe@SiO2-packed column was compared with that of Chiralpak AD-H. It was observed that certain enantiomers, which either could not be resolved or were inadequately separated on the Chiralpak AD-H column, attained separation on the 2D chiral MONs column. These findings suggest a complementary relationship between the two columns in racemate separation, with their combined application facilitating the resolution of a broader spectrum of chiral compounds. In addition, baseline separation was achieved for five positional isomers on the l-hyp-Ni/Fe@SiO2-packed column. The effects of the analyte mass and column temperature on the resolution were also examined. Moreover, during HPLC analysis, the l-hyp-Ni/Fe columns demonstrated commendable repeatability, stability and reproducibility in enantiomer separation. This research not only advances the utilisation of 2D chiral MONs as CSPs but also expands their applications in the separation sciences.
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Estruturas Metalorgânicas , Dióxido de Silício , Cromatografia Líquida de Alta Pressão/métodos , Dióxido de Silício/química , Estruturas Metalorgânicas/química , Estereoisomerismo , Nanoestruturas/química , Ferro/química , Níquel/químicaRESUMO
Two chiral covalent organic frameworks (CCOFs) core-shell microspheres based on achiral organic precursors by chiral-induced synthesis strategy for HPLC enantioseparation are reported for the first time. Using n-hexane/isopropanol as mobile phase, various kinds of racemates were selected as analytes and separated on the CCOF-TpPa-1@SiO2 and CCOF-TpBD@SiO2-packed columns with a low column backpressure (3 ~ 9 bar). The fabricated two CCOFs@SiO2 chiral columns exhibited good separation performance towards various racemates with high column efficiency (e.g., 19,500 plates m-1 for (4-fluorophenyl)ethanol and 18,900 plates m-1 for 1-(4-chlorophenyl)ethanol) and good reproducibility. Some effects have been investigated such as the analyte mass and column temperature on the HPLC enantioseparation. Moreover, the chiral separation results of the CCOF-TpPa-1@SiO2 chiral column and the commercialized Chiralpak AD-H column show a good complementarity. This study demonstrates that the usage of chiral-induced synthesis strategy for preparing CCOFs core-shell microspheres as a novel stationary phase has a good application potential in HPLC.
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Aptamers developed using in vitro Systematic Evolution of Ligands by Exponential Enrichment (SELEX) technology are single-stranded nucleic acids 10-100 nucleotides in length. Their targets, often with specificity and high affinity, range from ions and small molecules to proteins and other biological molecules as well as larger systems, including cells, tissues, and animals. Aptamers often rival conventional antibodies with improved performance, due to aptamers' unique biophysical and biochemical properties, including small size, synthetic accessibility, facile modification, low production cost, and low immunogenicity. Therefore, there is sustained interest in engineering and adapting aptamers for many applications, including diagnostics and therapeutics. Recently, aptamers have shown promise as early diagnostic biomarkers and in precision medicine for neurodegenerative and neurological diseases. Here, we critically review neuro-targeting aptamers and their potential applications in neuroscience research, neuro-diagnostics, and neuro-medicine. We also discuss challenges that must be overcome, including delivery across the blood-brain barrier, increased affinity, and improved in vivo stability and in vivo pharmacokinetic properties.
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Aptâmeros de Nucleotídeos , Neurociências , Animais , Aptâmeros de Nucleotídeos/química , Técnica de Seleção de Aptâmeros , Anticorpos , LigantesRESUMO
We compared methods to project absolute risk, the probability of experiencing the outcome of interest in a given projection interval accommodating competing risks, for a person from the target population with missing predictors. Without missing data, a perfectly calibrated model gives unbiased absolute risk estimates in a new target population, even if the predictor distribution differs from the training data. However, if predictors are missing in target population members, a reference dataset with complete data is needed to impute them and to estimate absolute risk, conditional only on the observed predictors. If the predictor distributions of the reference data and the target population differ, this approach yields biased estimates. We compared the bias and mean squared error of absolute risk predictions for seven methods that assume predictors are missing at random (MAR). Some methods imputed individual missing predictors, others imputed linear predictor combinations (risk scores). Simulations were based on real breast cancer predictor distributions and outcome data. We also analyzed a real breast cancer dataset. The largest bias for all methods resulted from different predictor distributions of the reference and target populations. No method was unbiased in this situation. Surprisingly, violating the MAR assumption did not induce severe biases. Most multiple imputation methods performed similarly and were less biased (but more variable) than a method that used a single expected risk score. Our work shows the importance of selecting predictor reference datasets similar to the target population to reduce bias of absolute risk predictions with missing risk factors.
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Neoplasias da Mama , Projetos de Pesquisa , Humanos , Feminino , Fatores de Risco , Viés , Interpretação Estatística de DadosRESUMO
Pathological hyperphosphorylation and aggregation of microtubule-associated Tau protein contribute to Alzheimer's Disease (AD) and other related tauopathies. Currently, no cure exists for Alzheimer's Disease. Aptamers offer significant potential as next-generation therapeutics in biotechnology and the treatment of neurological disorders. Traditional aptamer selection methods for Tau protein focus on binding affinity rather than interference with pathological Tau. In this study, we developed a new selection strategy to enrich DNA aptamers that bind to surviving monomeric Tau protein under conditions that would typically promote Tau aggregation. Employing this approach, we identified a set of aptamer candidates. Notably, BW1c demonstrates a high binding affinity (Kd=6.6â nM) to Tau protein and effectively inhibits arachidonic acid (AA)-induced Tau protein oligomerization and aggregation. Additionally, it inhibits GSK3ß-mediated Tau hyperphosphorylation in cell-free systems and okadaic acid-mediated Tau hyperphosphorylation in cellular milieu. Lastly, retro-orbital injection of BW1c tau aptamer shows the ability to cross the blood brain barrier and gain access to neuronal cell body. Through further refinement and development, these Tau aptamers may pave the way for a first-in-class neurotherapeutic to mitigate tauopathy-associated neurodegenerative disorders.
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Doença de Alzheimer , Tauopatias , Proteínas tau , Humanos , Doença de Alzheimer/metabolismo , Neurônios/metabolismo , Ácido Okadáico/metabolismo , Ácido Okadáico/farmacologia , Ácido Okadáico/uso terapêutico , Fosforilação , Proteínas tau/antagonistas & inibidores , Proteínas tau/metabolismo , Tauopatias/tratamento farmacológico , Tauopatias/metabolismo , Tauopatias/patologia , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/farmacologiaRESUMO
OBJECTIVE: To investigate the clinical potential and safety of Moluodan to reverse gastric precancerous lesions. METHODS: Patients aged 18-70 years diagnosed with moderate-to-severe atrophy and/or moderate-to-severe intestinal metaplasia, with or without low-grade dysplasia, and negative for Helicobacter pylori were recruited in this randomized, double-blind, parallel-controlled trial. The primary outcome was the improvement of global histological diagnosis at 1-year follow-up endoscopy using the operative link for gastritis assessment, the operative link for gastric intestinal metaplasia assessment, and the disappearance rate of dysplasia. RESULTS: Between November 3, 2017 and January 27, 2021, 166 subjects were randomly assigned to the Moluodan group, 168 to the folic acid group, 84 to the combination group, and 84 to the high-dose Moluodan group. The improvement in global histological diagnosis was achieved in 60 (39.5%) subjects receiving Moluodan, 59 (37.8%) receiving folic acid, 26 (32.1%) receiving the combined drugs, and 36 (47.4%) receiving high-dose Moluodan. Moluodan was non-inferior to folic acid (95% confidence interval: -9.2 to 12.5; P = 0.02). High-dose Moluodan had a trend for better protective efficacy, though there was no statistical significance. The disappearance rate of dysplasia was 82.8% in the Moluodan group, which was superior to folic acid (53.9%; P = 0.006). No drug-related serious adverse events were observed. CONCLUSIONS: One pack of Moluodan three times daily for 1 year was safe and effective in reversing gastric precancerous lesions, especially dysplasia. Doubling its dose showed a better efficacy trend.
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Medicamentos de Ervas Chinesas , Gastrite Atrófica , Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Gastrite Atrófica/tratamento farmacológico , Gastrite Atrófica/patologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/tratamento farmacológico , Lesões Pré-Cancerosas/tratamento farmacológico , Lesões Pré-Cancerosas/patologia , Metaplasia , Ácido Fólico/uso terapêutico , Mucosa Gástrica/patologiaRESUMO
PURPOSE: The study aimed to examine the consistency of vertebral bone quality (VBQ) scores for assessing osteoporosis across different etiologies and explore the predictive value of various VBQ scores for fragility vertebral fractures. METHODS: Patients with fragility fractures were matched by age and sex to patients with lumbar degeneration. VBQ scores were calculated in T1- and T2-weighted magnetic resonance imaging. Differential analysis of bone quality was performed based on etiology. RESULTS: A total of 96 inpatients were retrospectively enrolled. VBQT1 scores were only sensitive to osteoporotic bone in degenerative group (p < 0.01), failing to identify osteoporosis in fractured group (p > 0.05). For the degenerative group, the area under the curve (AUC) using the VBQT1 scores to differentiate osteoporosis was 0.72. After controlling the confounding variables, only VBQT2 scores were significantly higher in fractured group than degenerative group, with a greater AUC of 0.82 predicting fragility fractures. VBQT1 scores moderately correlated with femoral neck T-scores in degenerative group (r = -0.45, p < 0.01) but not in fractured group (r = -0.24, p > 0.05). VBQT2 scores were not associated with femoral neck T-scores (p > 0.05). CONCLUSION: This study is the first to evaluate the effectiveness of VBQs scores in assessing osteoporosis post-fracture. Only non-fractured patients' bone quality is fully susceptible to VBQT1 scores. While VBQT1 scores may not correlate with fragility fractures, VBQT2 scores present a viable alternative.
Assuntos
Osteoporose , Fraturas por Osteoporose , Humanos , Fraturas por Osteoporose/diagnóstico por imagem , Estudos Retrospectivos , Densidade Óssea , Vértebras Lombares/diagnóstico por imagem , Osteoporose/complicações , Osteoporose/diagnóstico por imagem , Imageamento por Ressonância Magnética/efeitos adversosRESUMO
BACKGROUND: The differences in outcomes after aneurysmal subarachnoid hemorrhage (aSAH) between the sexes have not been concretely determined. This study aimed to evaluate the differences in epidemiology, outcomes, and risk factors between male and female patients with aSAH. METHODS: We performed a multicenter, retrospective study of patients with aSAH from 2017 to 2020. We investigated the epidemiological differences between the two sexes. Propensity score matching (PSM) was used to compare short-term outcomes between the sexes. Binary logarithmic regression was performed to investigate the odds ratio (OR) for dependent survival in patients of different sexes. RESULTS: A total of 5,407 consecutive patients with aSAH were included in this study, and the female-to-male ratio was 1.8:1. The peak incidence of aSAH occurred in the 6th and 7th decades in males and females, respectively. There were more female patients with internal carotid artery or posterior communicating artery aneurysms (53.2%), and there were more male patients with anterior cerebral artery or anterior communicating artery aneurysms (43.2%). The incidence of multiple aneurysms was greater in female patients (21.5% vs. 14.2%, P < 0.001). There was no significant difference in outcomes before and after PSM at discharge. The dependent survival risk was related only to the clinical condition on admission in women. In addition, age > 50 years (OR 1.88, 95% confidence interval 1.17-3.02; P = 0.01) and hypertension (OR 1.81, 95% confidence interval 1.25-2.61; P = 0.002) were also risk factors for male patients. CONCLUSIONS: There were more female patients with aneurysms than male patients in this study. Most aneurysm locations were different between the two groups. There was no significant difference in discharge outcomes before and after PSM. The risk factors for dependent survival were different between female and male patients.
Assuntos
Hemorragia Subaracnóidea , Humanos , Hemorragia Subaracnóidea/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Risco , Estudos Retrospectivos , Adulto , Idoso , Fatores Sexuais , Aneurisma Intracraniano/epidemiologia , Incidência , Pontuação de PropensãoRESUMO
Cytosine DNA methylation is essential in brain development and is implicated in various neurological disorders. Understanding DNA methylation diversity across the entire brain in a spatial context is fundamental for a complete molecular atlas of brain cell types and their gene regulatory landscapes. Here we used single-nucleus methylome sequencing (snmC-seq3) and multi-omic sequencing (snm3C-seq)1 technologies to generate 301,626 methylomes and 176,003 chromatin conformation-methylome joint profiles from 117 dissected regions throughout the adult mouse brain. Using iterative clustering and integrating with companion whole-brain transcriptome and chromatin accessibility datasets, we constructed a methylation-based cell taxonomy with 4,673 cell groups and 274 cross-modality-annotated subclasses. We identified 2.6 million differentially methylated regions across the genome that represent potential gene regulation elements. Notably, we observed spatial cytosine methylation patterns on both genes and regulatory elements in cell types within and across brain regions. Brain-wide spatial transcriptomics data validated the association of spatial epigenetic diversity with transcription and improved the anatomical mapping of our epigenetic datasets. Furthermore, chromatin conformation diversities occurred in important neuronal genes and were highly associated with DNA methylation and transcription changes. Brain-wide cell-type comparisons enabled the construction of regulatory networks that incorporate transcription factors, regulatory elements and their potential downstream gene targets. Finally, intragenic DNA methylation and chromatin conformation patterns predicted alternative gene isoform expression observed in a whole-brain SMART-seq2 dataset. Our study establishes a brain-wide, single-cell DNA methylome and 3D multi-omic atlas and provides a valuable resource for comprehending the cellular-spatial and regulatory genome diversity of the mouse brain.