Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
1.
N Engl J Med ; 390(23): 2178-2190, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899695

RESUMO

BACKGROUND: Immune thrombocytopenia (ITP) is an autoimmune disease characterized by autoantibody-mediated platelet destruction. Treatment with CM313, a novel anti-CD38 monoclonal antibody, can result in targeted clearance of CD38-positive cells, including plasma cells. METHODS: We conducted a phase 1-2, open-label study to evaluate the safety and efficacy of CM313 in adult patients with ITP. CM313 was administered intravenously at a dose of 16 mg per kilogram of body weight every week for 8 weeks, followed by a 16-week follow-up period. The primary outcomes were adverse events and documentation of two or more consecutive platelet counts of at least 50×109 per liter within 8 weeks after the first dose of CM313. The status of peripheral-blood immune cells in patients and changes in the mononuclear phagocytic system in passive mouse models of ITP receiving anti-CD38 therapy were monitored. RESULTS: Of the 22 patients included in the study, 21 (95%) had two consecutive platelet counts of at least 50×109 per liter during the treatment period, with a median cumulative response duration of 23 weeks (interquartile range, 17 to 24). The median time to the first platelet count of at least 50×109 per liter was 1 week (range, 1 to 3). The most common adverse events that occurred during the study were infusion-related reaction (in 32% of the patients) and upper respiratory tract infection (in 32%). After CD38-targeted therapy, the percentage of CD56dimCD16+ natural killer cells, the expression of CD32b on monocytes in peripheral blood, and the number of macrophages in the spleen of the passive mouse models of ITP all decreased. CONCLUSIONS: In this study, anti-CD38 targeted therapy rapidly boosted platelet levels by inhibiting antibody-dependent cell-mediated cytotoxicity on platelets, maintained long-term efficacy by clearing plasma cells, and was associated with mainly low-grade toxic effects. (Funded by the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences and others; ClinicalTrials.gov number, NCT05694767).


Assuntos
Anticorpos Monoclonais , Púrpura Trombocitopênica Idiopática , Adulto , Idoso , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/efeitos adversos , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/imunologia
2.
Br J Haematol ; 204(6): 2418-2428, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38513635

RESUMO

This study aimed to identify key proteomic analytes correlated with response to splenectomy in primary immune thrombocytopenia (ITP). Thirty-four patients were retrospectively collected in the training cohort and 26 were prospectively enrolled as validation cohort. Bone marrow biopsy samples of all participants were collected prior to the splenectomy. A total of 12 modules of proteins were identified by weighted gene co-expression network analysis (WGCNA) method in the developed cohort. The tan module positively correlated with megakaryocyte counts before splenectomy (r = 0.38, p = 0.027), and time to peak platelet level after splenectomy (r = 0.47, p = 0.005). The blue module significantly correlated with response to splenectomy (r = 0.37, p = 0.0031). KEGG pathways analysis found that the PI3K-Akt signalling pathway was predominantly enriched in the tan module, while ribosomal and spliceosome pathways were enriched in the blue module. Machine learning algorithm identified the optimal combination of biomarkers from the blue module in the training cohort, and importantly, cofilin-1 (CFL1) was independently confirmed in the validation cohort. The C-index of CFL1 was >0.7 in both cohorts. Our results highlight the use of bone marrow proteomics analysis for deriving key analytes that predict the response to splenectomy, warranting further exploration of plasma proteomics in this patient population.


Assuntos
Aprendizado de Máquina , Proteômica , Púrpura Trombocitopênica Idiopática , Esplenectomia , Humanos , Masculino , Feminino , Proteômica/métodos , Púrpura Trombocitopênica Idiopática/cirurgia , Púrpura Trombocitopênica Idiopática/sangue , Púrpura Trombocitopênica Idiopática/genética , Adulto , Pessoa de Meia-Idade , Biomarcadores/sangue , Idoso , Estudos Retrospectivos
3.
Br J Haematol ; 204(6): 2405-2417, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38438130

RESUMO

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by antibody-mediated platelet destruction and impaired platelet production. The mechanisms underlying ITP and biomarkers predicting the response of drug treatments are elusive. We performed a metabolomic profiling of bone marrow biopsy samples collected from ITP patients admission in a prospective study of the National Longitudinal Cohort of Hematological Diseases. Machine learning algorithms were conducted to discover novel biomarkers to predict ITP patient treatment responses. From the bone marrow biopsies of 91 ITP patients, we quantified a total of 4494 metabolites, including 1456 metabolites in the positive mode and 3038 metabolites in the negative mode. Metabolic patterns varied significantly between groups of newly diagnosed and chronic ITP, with a total of 876 differential metabolites involved in 181 unique metabolic pathways. Enrichment factors and p-values revealed the top metabolically enriched pathways to be sphingolipid metabolism, the sphingolipid signalling pathway, ubiquinone and other terpenoid-quinone biosynthesis, thiamine metabolism, tryptophan metabolism and cofactors biosynthesis, the phospholipase D signalling pathway and the phosphatidylinositol signalling system. Based on patient responses to five treatment options, we screened several metabolites using the Boruta algorithm and ranked their importance using the random forest algorithm. Lipids and their metabolism, including long-chain fatty acids, oxidized lipids, glycerophospholipids, phosphatidylcholine and phosphatidylethanolamine biosynthesis, helped differentiate drug treatment responses. In conclusion, this study revealed metabolic alterations associated with ITP in bone marrow supernatants and a potential biomarker predicting the response to ITP.


Assuntos
Aprendizado de Máquina , Metabolômica , Púrpura Trombocitopênica Idiopática , Humanos , Púrpura Trombocitopênica Idiopática/metabolismo , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/sangue , Estudos Prospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Metabolômica/métodos , Adulto , Idoso , Biomarcadores , Metaboloma , Redes e Vias Metabólicas , Resultado do Tratamento , Medula Óssea/metabolismo , Medula Óssea/patologia
4.
Bioorg Med Chem Lett ; 99: 129624, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38272190

RESUMO

A structurally novel class of benzo- or pyrido-fused 1,3-dihydro-2H-imidazole-2-imines was designed and evaluated in an inositol phosphate accumulation assay for Gq signaling to measure agonistic activation of the orexin receptor type 2 (OX2R). These compounds were synthesized in 4-9 steps overall from readily available starting materials. Analogs that contain a stereogenic methyl or cyclopropyl substituent at the benzylic center, and a correctly configured alkyl ether, alkoxyalkyl ether, cyanoalkyl ether, or α-hydroxyacetamido substituted homobenzylic sidechain were identified as the most potent activators of OX2R coupled Gq signaling. Our results also indicate that agonistic activity was stereospecific at both the benzylic and homobenzylic stereogenic centra. We identified methoxyethoxy-substituted pyrido-fused dihydroimidazolimine analog 63c containing a stereogenic benzylic methyl group was the most potent agonist, registering a respectable EC50 of 339 nM and a maximal response (Emax) of 96 % in this assay. In vivo pharmacokinetic analysis indicated good brain exposure for several analogs. Our combined results provide important information towards a structurally novel class of orexin receptor agonists distinct from current chemotypes.


Assuntos
Imidazóis , Iminas , Receptores de Orexina/agonistas , Iminas/farmacologia , Imidazóis/farmacologia , Piridinas , Éteres
5.
Br J Haematol ; 201(4): 690-703, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36708268

RESUMO

JAK2V617F is the most frequent mutation in BCR-ABL-negative myeloproliferative neoplasms (MPNs). It is an important but not the only determinant of MPN phenotype. We performed high-throughput sequencing on JAK2V617F+ essential thrombocythaemia (ET) and polycythaemia vera (PV) patient samples to unveil factors involved in phenotypic heterogeneity and to identify novel therapeutic targets for MPN. Two concurrent mutations that may affect phenotype were identified, including mutations in SH2B3, which is primarily prevalent in PV, and SF3B1, which is more commonly mutated in ET. Next, we conducted transcriptomic analysis at the haematopoietic stem cell (HSC) and megakaryocyte (MK)-erythroid progenitor (MEP) levels. Inflammatory signalling pathways were elevated in both ET HSCs and MEPs, unlike in PV HSCs and MEPs. Notably, Wnt/ß-catenin signalling was uniquely upregulated during ET haematopoietic differentiation from HSC to MEP, and inhibiting Wnt/ß-catenin signalling blocked MK differentiation in vitro. Consistently, Wnt/ß-catenin inhibitor administration decreased platelet counts in JAK2V617F+ MPN mice by blocking MEPs and MK progenitors and by inhibiting maturation of MKs, while in wild-type mice, Wnt/ß-catenin inhibitor did not significantly reduce platelet counts. In conclusion, our findings provide new insights into the mechanisms underlying phenotypic differentiation of JAK2V617F+ PV and ET and indicate Wnt/ß-catenin signalling as a potential therapeutic target for MPN.


Assuntos
Transtornos Mieloproliferativos , Policitemia Vera , Trombocitemia Essencial , Animais , Camundongos , beta Catenina , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Policitemia Vera/tratamento farmacológico , Policitemia Vera/genética , Trombocitemia Essencial/tratamento farmacológico , Trombocitemia Essencial/genética , Mutação , Fenótipo , Janus Quinase 2/genética
6.
J Thromb Thrombolysis ; 56(2): 291-300, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37249742

RESUMO

The current study involving 318 essential thrombocythemia (ET) patients with prior thrombosis was designed to identify risk factors that were predictive of recurrent thrombosis. The whole cohort was randomly split into derivation and validation cohorts. The random forest method, support vector machine with built-in recursive feature elimination model, and logistic multivariable analysis were performed in the derivation cohort, and cardiovascular risk factor (CVF) and RBC distribution width with standard deviation (RDW-SD) were finally selected as independent predictors. Subsequently we devise a 3-tiered model (low risk: 0 points; intermediate risk: 1-1.5 points; and high risk: 2.5 points) and it showed good discrimination in all cohorts. Moreover, the model was significantly correlated with rethrombosis-free survival (rTFS) (p = 0.0007 in the derivation cohort; p = 0.0019 in the validation cohort). In the whole cohort, cytoreductive therapy was more effective than antiplatelet agents alone for 10-year rTFS (p = 0.0336). No significant difference in 10-year rTFS was observed among interferon (IFN), hydroxyurea (HU), and IFN + HU therapy (p = 0.444). The present study helps identify individuals who need close monitoring and provides valuable risk signals for recurrence in ET patients with prior thrombosis.


Assuntos
Trombocitemia Essencial , Trombose , Humanos , Adulto , Trombocitemia Essencial/complicações , Trombocitemia Essencial/tratamento farmacológico , Trombose/etiologia , Hidroxiureia/uso terapêutico , Fatores de Risco , Inibidores da Agregação Plaquetária/uso terapêutico
7.
Nucleic Acids Res ; 49(2): 969-985, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33398341

RESUMO

Investigations of CRISPR gene knockout editing profiles have contributed to enhanced precision of editing outcomes. However, for homology-directed repair (HDR) in particular, the editing dynamics and patterns in clinically relevant cells, such as human iPSCs and primary T cells, are poorly understood. Here, we explore the editing dynamics and DNA repair profiles after the delivery of Cas9-guide RNA ribonucleoprotein (RNP) with or without the adeno-associated virus serotype 6 (AAV6) as HDR donors in four cell types. We show that editing profiles have distinct differences among cell lines. We also reveal the kinetics of HDR mediated by the AAV6 donor template. Quantification of T50 (time to reach half of the maximum editing frequency) indicates that short indels (especially +A/T) occur faster than longer (>2 bp) deletions, while the kinetics of HDR falls between NHEJ (non-homologous end-joining) and MMEJ (microhomology-mediated end-joining). As such, AAV6-mediated HDR effectively outcompetes the longer MMEJ-mediated deletions but not NHEJ-mediated indels. Notably, a combination of small molecular compounds M3814 and Trichostatin A (TSA), which potently inhibits predominant NHEJ repairs, leads to a 3-fold increase in HDR efficiency.


Assuntos
Sistemas CRISPR-Cas , Reparo do DNA por Junção de Extremidades , Edição de Genes , Vetores Genéticos/genética , Parvovirinae/genética , Reparo de DNA por Recombinação , Ribonucleoproteínas/metabolismo , Adulto , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA , Reparo do DNA por Junção de Extremidades/efeitos dos fármacos , Dependovirus , Células HEK293 , Humanos , Ácidos Hidroxâmicos/farmacologia , Mutação INDEL , Células-Tronco Pluripotentes Induzidas , Cinética , RNA Guia de Cinetoplastídeos/genética , Reparo de DNA por Recombinação/efeitos dos fármacos , Linfócitos T , Transdução Genética
8.
J Am Chem Soc ; 142(13): 6128-6138, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32163279

RESUMO

TASIN (Truncated APC-Selective Inhibitors) compounds are selectively toxic to colorectal cancer cells with APC mutations, although their mechanism of action remains unknown. Here, we found that TASINs inhibit three enzymes in the postsqualene cholesterol biosynthetic pathway including EBP, DHCR7, and DHCR24. Even though all three of these enzymes are required for cholesterol biosynthesis, only inhibition of the most upstream enzyme, EBP, led to cancer cell death via depletion of downstream sterols, an observation that was confirmed by genetic silencing of EBP. Pharmacologic inhibition or genetic silencing of either DHCR7 or DHCR24 had no impact on cell viability. By using photoaffinity probes to generate a relationship between chemical structure and probe competition, we identified compounds that selectively inhibit either EBP or DHCR7. These studies identify EBP, but not downstream enzymes in the cholesterol biosynthetic pathway, as a target in APC mutant colorectal cancer and also have implications for the clinical development of highly selective EBP inhibitors.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Esteroide Isomerases/antagonistas & inibidores , Proteína da Polipose Adenomatosa do Colo/genética , Antineoplásicos/química , Vias Biossintéticas/efeitos dos fármacos , Colesterol/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Descoberta de Drogas , Inibidores Enzimáticos/química , Células HCT116 , Humanos , Mutação , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Esteroide Isomerases/metabolismo
9.
Biochem Biophys Res Commun ; 521(2): 326-332, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31668371

RESUMO

Hematopoiesis is systematically regulated by microenvironmental factors. The positive and negative factors coordinated together to yield a complicated blood system. Interferon-γ (IFNγ) has been identified as a common cause of various hematopoietic abnormalities, such as aplastic anemia. However, its impact on monolineage development, especially erythropoiesis, has not been fully elucidated from the cellular angle. In this study, we investigated the behavior of IFNγ and found that IFNγ plays dual functions on erythropoiesis; it not only blocks the erythroid lineage commitment but also accelerates the erythroid differentiation process, ultimately leading to the erythropoietic window clearance. IFNγ can even powerfully initiate early differentiation without the existence of erythropoietin (EPO). Interferon regulatory factor 1 (IRF1) was confirmed as the essential downstream effector, and its ectopic overexpression can also have the same effect as that of IFNγ. These results reveal that the IFNγ-IRF1 axis plays a bidirectional role on erythropoiesis, impeding the access to erythroid lineage and driving the coming cells toward the differentiation endpoint. This model may place an innovative implication for IFNγ-IRF1 axis to understand its in-depth mechanism on normal hematopoiesis and abnormal blood disorders, especially aplastic anemia.


Assuntos
Eritropoese/efeitos dos fármacos , Fator Regulador 1 de Interferon/metabolismo , Interferon gama/farmacologia , Transdução de Sinais , Anemia Aplástica , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Células Cultivadas , Humanos
10.
Haematologica ; 105(3): 661-673, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31289202

RESUMO

The role of the bone marrow niche in essential thrombocythemia (ET) remains unclear. Here, we observed multilevel defects in the hematopoietic niche of patients with JAK2V617F-positive ET, including functional deficiency in mesenchymal stromal cells (MSC), immune imbalance, and sympathetic-nerve damage. Mesenchymal stromal cells from patients with JAK2V617F-positive essential thrombocythemia had a transformed transcriptome. In parallel, they showed enhanced proliferation, decreased apoptosis and senescence, attenuated ability to differentiate into adipocytes and osteocytes, and insufficient support for normal hematopoiesis. Additionally, they were inefficient in suppressing immune responses. For instance, they poorly inhibited proliferation and activation of CD4-positive T cells and the secretion of the inflammatory factor soluble CD40-ligand. They also poorly induced formation of mostly immunosuppressive T-helper 2 cells (Th2) and the secretion of the anti-inflammatory factor interleukin-4 (IL-4). Furthermore, we identified WDR4 as a potent protein with low expression and which was correlated with increased proliferation, reduced senescence and differentiation, and insufficient support for normal hematopoiesis in MSC from patients with JAK2V617F-positive ET. We also observed that loss of WDR4 in MSC cells downregulated the interleukin-6 (IL-6) level through the ERK-GSK3ß-CREB signaling based on our in vitro studies. Altogether, our results show that multilevel changes occur in the bone marrow niche of patients with JAK2V617F-positive ET, and low expression of WDR4 in MSC may be critical for inducing hematopoietic related changes.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Trombocitemia Essencial , Células da Medula Óssea , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Proteínas de Ligação ao GTP , Hematopoese , Humanos , Trombocitemia Essencial/genética
11.
Sensors (Basel) ; 20(20)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066663

RESUMO

The directional borehole radar can accurately locate and image the geological target around the borehole, which overcomes the shortcomings that the conventional borehole radar can only detect the depth of the target and the distance from the borehole. The directional borehole radar under consideration consists of a transmitting antenna and four receiving antennas equally distributed on the ring in the borehole. The nonuniformity caused by the borehole and sonde, as well as the mutual coupling among the four receiving antennas, will have a serious impact on the received signal and then cause interference to the azimuth recognition for the targets. In this paper, Finite difference time domain (FDTD), including the subgrid, is applied to study these effects and interferences, and the influence of borehole, sonde, and mutual coupling among the receiving antennas is found. The results show that, without considering the sonde and the fluid in the borehole, the one transmitting and one receiving borehole radar system does not have resonance, but the wave pattern of the reflected wave will have obvious distortion. For the four receiving antennas of the borehole radar system, there is obvious resonance, which is caused by the multiple reflections between the receiving antennas. However, when the fluid in the borehole is water and the relative permittivity of the sonde is low to a certain extent, the resonance disappears; that is, the generation of resonance requires a large relative permittivity material between the receiving antennas. When the influence of the sonde is considered, the resonance disappears because the relative permittivity of the sonde is low, which makes the propagation speed of the electromagnetic wave between the antennas accelerate and lose the conditions for resonance. In addition, the diameters of the sonde and the circular array of the receiving antennas can affect the received signal: the higher the diameter of the sonde and the higher the diameter of the circular array are, the better the differentiation of the received signal. The development of the research provides scientific guidance for the design and application of borehole radar in the future.

14.
Blood ; 123(2): 261-70, 2014 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-24255919

RESUMO

Promyelocytic leukemia protein (PML) has been implicated as a participant in multiple cellular processes including senescence, apoptosis, proliferation, and differentiation. Studies of PML function in hematopoietic differentiation previously focused principally on its myeloid activities and also indicated that PML is involved in erythroid colony formation. However, the exact role that PML plays in erythropoiesis is essentially unknown. In this report, we found that PML4, a specific PML isoform expressed in erythroid cells, promotes endogenous erythroid genes expression in K562 and primary human erythroid cells. We show that the PML4 effect is GATA binding protein 1 (GATA-1) dependent using GATA-1 knockout/rescued G1E/G1E-ER4 cells. PML4, but not other detected PML isoforms, directly interacts with GATA-1 and can recruit it into PML nuclear bodies. Furthermore, PML4 facilitates GATA-1 trans-activation activity in an interaction-dependent manner. Finally, we present evidence that PML4 enhances GATA-1 occupancy within the globin gene cluster and stimulates cooperation between GATA-1 and its coactivator p300. These results demonstrate that PML4 is an important regulator of GATA-1 and participates in erythroid differention by enhancing GATA-1 trans-activation activity.


Assuntos
Diferenciação Celular/fisiologia , Células Eritroides/citologia , Células Eritroides/metabolismo , Fator de Transcrição GATA1/genética , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Ativação Transcricional , Proteínas Supressoras de Tumor/metabolismo , Acetilação , Proteína p300 Associada a E1A/metabolismo , Fator de Transcrição GATA1/química , Fator de Transcrição GATA1/metabolismo , Expressão Gênica , Humanos , Células K562 , Proteínas Nucleares/química , Proteínas Nucleares/genética , Proteína da Leucemia Promielocítica , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Isoformas de Proteínas , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/genética , Transcrição Gênica , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética , Dedos de Zinco
15.
Rapid Commun Mass Spectrom ; 29(19): 1711-6, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26331921

RESUMO

RATIONALE: Although traditional analytical techniques like gas chromatography (GC) and GC/mass spectrometry (MS) offer satisfactory sensitivity and good reproducibility for the detection of phthalic acid esters (PAEs) in a variety of matrices, they involve laborious sample pretreatment, are time-consuming, and some are expensive and environmentally unfriendly. Furthermore, there are thousands of spirits on the market; therefore, rapid and high-throughout methods suitable for the consistent detection and quantification of PAEs in spirits are urgently required. METHODS: A new atmospheric pressure ionization method, named air-flow-assisted extractive electrospray ionization (EESI), has been developed. It is a variant on EESI and possesses the advantages of both EESI and air-flow-assisted ionization for direct analysis of samples without pretreatment. Combined with a quadrupole time-of-flight (QTOF) mass spectrometer, the method was used to directly analyze four PAEs, i.e., dipentyl phthalate, diethyl phthalate, benzyl butyl phthalate and didecyl phthalate, in spirits. RESULTS: The method exhibits excellent sensitivity, stability and convenience. Four different brands of spirits have been successfully analyzed. The total analysis time for one sample was within 1 min, and the limits of detection and limits of quantification of the samples are located in the range 0.011-0.035 and 0.038-0.087 µg g(-1), respectively. Very good linearities, with correlation coefficients of 0.9758-0.9990, are observed for the samples in the range of 0.035 to 10 µg g(-1). CONCLUSIONS: The results indicate that the air-flow-assisted EESI combined with tandem mass spectrometry is an effective method for rapid and direct determination of PAEs in spirits without sample pretreatment.

16.
Int J Mol Sci ; 16(3): 6202-16, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25789505

RESUMO

Tensile tests were performed on two different natural fibre composites (same constituent material, similar fibre fraction and thickness but different weave structure) to determine changes in mechanical properties caused by various aqueous chemical treatments and whether any permanent changes remain on drying. Scanning electronic microscopic examinations suggested that flax fibres and the flax/polypropylene interface were affected by the treatments resulting in tensile property variations. The ductility of natural fibre composites was improved significantly under wet condition and mechanical properties (elongation-to-failure, stiffness and strength) can almost retain back to pre-treated levels when dried from wet condition. Preheating is usually required to improve the formability of material in rapid forming, and the chemical treatments performed in this study were far more effective than preheating. The major breakthrough in improving the formability of natural fibre composites can aid in rapid forming of this class of material system.


Assuntos
Linho/química , Polipropilenos/química , Linho/metabolismo , Microscopia Eletrônica de Varredura , Resistência à Tração , Molhabilidade
17.
Nucleic Acids Res ; 40(11): 4804-15, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22328728

RESUMO

The higher order chromatin structure has recently been revealed as a critical new layer of gene transcriptional control. Changes in higher order chromatin structures were shown to correlate with the availability of transcriptional factors and/or MAR (matrix attachment region) binding proteins, which tether genomic DNA to the nuclear matrix. How posttranslational modification to these protein organizers may affect higher order chromatin structure still pending experimental investigation. The type III histone deacetylase silent mating type information regulator 2, S. cerevisiae, homolog 1 (SIRT1) participates in many physiological processes through targeting both histone and transcriptional factors. We show that MAR binding protein SATB1, which mediates chromatin looping in cytokine, MHC-I and ß-globin gene loci, as a new type of SIRT1 substrate. SIRT1 expression increased accompanying erythroid differentiation and the strengthening of ß-globin cluster higher order chromatin structure, while knockdown of SIRT1 in erythroid k562 cells weakened the long-range interaction between two SATB1 binding sites in the ß-globin locus, MAR(HS2) and MAR(ε). We also show that SIRT1 activity significantly affects ε-globin gene expression in a SATB1-dependent manner and that knockdown of SIRT1 largely blocks ε-globin gene activation during erythroid differentiation. Our work proposes that SIRT1 orchestrates changes in higher order chromatin structure during erythropoiesis, and reveals the dynamic higher order chromatin structure regulation at posttranslational modification level.


Assuntos
Regulação da Expressão Gênica , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Regiões de Interação com a Matriz , Sirtuína 1/metabolismo , Globinas épsilon/genética , Células Cultivadas , Células Eritroides/efeitos dos fármacos , Células Eritroides/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Hemina/farmacologia , Humanos , Células K562 , Região de Controle de Locus Gênico , Globinas beta/genética , Globinas épsilon/biossíntese
18.
Quintessence Int ; 55(2): 120-128, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-37870595

RESUMO

OBJECTIVES: The role of antibiotics as an adjunct to nonsurgical peri-implantitis treatment approaches has not reached a consensus. This meta-analysis aimed to review the adjunctive effect of systemic use of metronidazole and amoxicillin in patients with peri-implantitis. METHOD AND MATERIALS: PubMed, Embase, and the Cochrane Library were searched for randomized controlled trials published from inception to January 2023. RESULTS: A total of five clinical trials with a total of 211 patients were included in the analyses. No significant difference was found in the reduction of probing pocket depth at 3 and 6 months of follow-up (3 months: weighted mean difference [WMD] = -0.336, 95% CI -0.966 to 0.233, P = .231; 6 months: WMD = -0.533, 95% CI -1.654 to 0.587, P = .351). A statistically significant difference was found at 12 months of follow-up (WMD = -1.327, 95% CI -1.803 to -0.852, P < .001) between the treatment and control groups. The combined results indicated that the differences in reduction of bleeding on probing, Plaque Index score, and bone level at 6 months of follow-up were significant (P < .05). CONCLUSION: The study demonstrated that the adjunctive use of systemic metronidazole and amoxicillin did not significantly improve probing pocket depth compared to nonsurgical treatment alone, and should not be routinely recommended. However, the significant reductions in bleeding on probing, Plaque Index, and bone level at 6 months may indicate a potential effect of treating peri-implantitis with adjunctive systemic metronidazole and amoxicillin.


Assuntos
Implantes Dentários , Peri-Implantite , Humanos , Peri-Implantite/tratamento farmacológico , Antibacterianos/uso terapêutico , Metronidazol/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Amoxicilina/uso terapêutico
19.
Front Genet ; 15: 1293477, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38482383

RESUMO

Studying how populations in various environments differ genetically is crucial for gaining insights into the evolution of biodiversity. In order to pinpoint potential indicators of divergence and adaptation to diverse environments, we conducted a comprehensive analysis of 3,491,868 single nucleotide polymorphisms (SNPs) derived from five populations of Brachymystax lenok. We discovered significant geographic divergence among these 5 populations, which lack evidence of gene flow among them. Our results further demonstrated that the current distribution pattern of Brachymystax lenok are driven by geographical isolation and changes in oceans and rivers. We also performed genome-wide scan and identified the genes evolved to adapt the different environments, including stress response. In general, these results provide genomic support for high-level genetic divergence and the genetic basis of adaptation to different environments.

20.
Clin Exp Med ; 24(1): 154, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38972952

RESUMO

Essential thrombocythemia (ET) and prefibrotic primary myelofibrosis (pre-PMF) are Philadelphia chromosome-negative myeloproliferative neoplasms. These conditions share overlapping clinical presentations; however, their prognoses differ significantly. Current morphological diagnostic methods lack reliability in subtype differentiation, underlining the need for improved diagnostics. The aim of this study was to investigate the multi-omics alterations in bone marrow biopsies of patients with ET and pre-PMF to improve our understanding of the nuanced diagnostic characteristics of both diseases. We performed proteomic analysis with 4D direct data-independent acquisition and microbiome analysis with 2bRAD-M sequencing technology to identify differential protein and microbe levels between untreated patients with ET and pre-PMF. Laboratory and multi-omics differences were observed between ET and pre-PMF, encompassing diverse pathways, such as lipid metabolism and immune response. The pre-PMF group showed an increased neutrophil-to-lymphocyte ratio and decreased high-density lipoprotein and cholesterol levels. Protein analysis revealed significantly higher CXCR2, CXCR4, and MX1 levels in pre-PMF, while APOC3, APOA4, FABP4, C5, and CFB levels were elevated in ET, with diagnostic accuracy indicated by AUC values ranging from 0.786 to 0.881. Microbiome assessment identified increased levels of Mycobacterium, Xanthobacter, and L1I39 in pre-PMF, whereas Sphingomonas, Brevibacillus, and Pseudomonas_E were significantly decreased, with AUCs for these genera ranging from 0.833 to 0.929. Our study provides preliminary insights into the proteomic and microbiome variations in the bone marrow of patients with ET and pre-PMF, identifying specific proteins and bacterial genera that warrant further investigation as potential diagnostic indicators. These observations contribute to our evolving understanding of the multi-omics variations and possible mechanisms underlying ET and pre-PMF.


Assuntos
Medula Óssea , Mielofibrose Primária , Proteômica , Trombocitemia Essencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biópsia , Medula Óssea/patologia , Medula Óssea/microbiologia , Diagnóstico Diferencial , Microbiota , Multiômica , Mielofibrose Primária/patologia , Trombocitemia Essencial/patologia , Trombocitemia Essencial/diagnóstico , Trombocitemia Essencial/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA