Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 794
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Annu Rev Cell Dev Biol ; 31: 125-47, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26436705

RESUMEN

Hepatitis B virus (HBV) infection affects 240 million people worldwide. A liver-specific bile acid transporter named the sodium taurocholate cotransporting polypeptide (NTCP) has been identified as the cellular receptor for HBV and its satellite, the hepatitis D virus (HDV). NTCP likely acts as a major determinant for the liver tropism and species specificity of HBV and HDV at the entry level. NTCP-mediated HBV entry interferes with bile acid transport in cell cultures and has been linked with alterations in bile acid and cholesterol metabolism in vivo. The human liver carcinoma cell line HepG2, complemented with NTCP, now provides a valuable platform for studying the basic biology of the viruses and developing treatments for HBV infection. This review summarizes critical findings regarding NTCP's role as a viral receptor for HBV and HDV and discusses important questions that remain unanswered.


Asunto(s)
Virus de la Hepatitis B/metabolismo , Receptores de Superficie Celular/metabolismo , Animales , Proteínas Portadoras/metabolismo , Virus de la Hepatitis Delta/metabolismo , Humanos , Glicoproteínas de Membrana/metabolismo , Transportadores de Anión Orgánico Sodio-Dependiente/metabolismo , Simportadores/metabolismo
2.
Plant J ; 118(6): 1937-1954, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38491870

RESUMEN

Chilling stress causes banana fruit softening disorder and severely impairs fruit quality. Various factors, such as transcription factors, regulate fruit softening. Herein, we identified a novel regulator, MaC2H2-IDD, whose expression is closely associated with fruit ripening and softening disorder. MaC2H2-IDD is a transcriptional activator located in the nucleus. The transient and ectopic overexpression of MaC2H2-IDD promoted "Fenjiao" banana and tomato fruit ripening. However, transient silencing of MaC2H2-IDD repressed "Fenjiao" banana fruit ripening. MaC2H2-IDD modulates fruit softening by activating the promoter activity of starch (MaBAM3, MaBAM6, MaBAM8, MaAMY3, and MaISA2) and cell wall (MaEXP-A2, MaEXP-A8, MaSUR14-like, and MaGLU22-like) degradation genes. DLR, Y1H, EMSA, and ChIP-qPCR assays validated the expression regulation. MaC2H2-IDD interacts with MaEBF1, enhancing the regulation of MaC2H2-IDD to MaAMY3, MaEXP-A2, and MaGLU22-like. Overexpressing/silencing MaC2H2-IDD in banana and tomato fruit altered the transcript levels of the cell wall and starch (CWS) degradation genes. Several differentially expressed genes (DEGs) were authenticated between the overexpression and control fruit. The DEGs mainly enriched biosynthesis of secondary metabolism, amino sugar and nucleotide sugar metabolism, fructose and mannose metabolism, starch and sucrose metabolism, and plant hormones signal transduction. Overexpressing MaC2H2-IDD also upregulated protein levels of MaEBF1. MaEBF1 does not ubiquitinate or degrade MaC2H2-IDD. These data indicate that MaC2H2-IDD is a new regulator of CWS degradation in "Fenjiao" banana and cooperates with MaEBF1 to modulate fruit softening, which also involves the cold softening disorder.


Asunto(s)
Respuesta al Choque por Frío , Frutas , Regulación de la Expresión Génica de las Plantas , Musa , Proteínas de Plantas , Musa/genética , Musa/metabolismo , Musa/fisiología , Frutas/genética , Frutas/metabolismo , Frutas/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Respuesta al Choque por Frío/genética , Solanum lycopersicum/genética , Solanum lycopersicum/fisiología , Solanum lycopersicum/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Plantas Modificadas Genéticamente , Pared Celular/metabolismo , Almidón/metabolismo
3.
Development ; 149(24)2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36515165

RESUMEN

Flowering time is an important agronomic trait affecting crop yield. FCS-LIKE ZINC FINGER (FLZ) proteins are plant-specific regulatory proteins that are involved in multiple biological processes. However, their roles in plant flowering time control have not been clarified. Here, we report that OsFLZ2 is a negative regulator of rice flowering time. OsFLZ2 delays flowering by repressing the expression of key floral integrator genes. Biochemical assays showed OsFLZ2 physically interacts with OsMADS51, a flowering activator under short-day (SD) conditions. Both OsFLZ2 and OsMADS51 are highly expressed in rice leaves before floral transition under natural SD conditions, and their proteins are colocalized in the nucleus. Co-expression of OsFLZ2 can destabilize OsMADS51 and weaken its transcriptional activation of the downstream target gene Early heading date 1 (Ehd1). Taken together, these results indicate that OsFLZ2 can interfere with the function of OsMADS51 to fine-tune rice flowering time.


Asunto(s)
Oryza , Oryza/genética , Oryza/metabolismo , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Fotoperiodo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
Nano Lett ; 24(28): 8580-8586, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38967330

RESUMEN

By using low-temperature scanning tunneling microscopy and spectroscopy (STM/STS), we observe in-gap states induced by Andreev tunneling through a single impurity state in a low carrier density superconductor (NaAlSi). The energy-symmetric in-gap states appear when the impurity state is located within the superconducting gap. In-gap states can cross the Fermi level, and they show X-shaped spatial variation. We interpret the in-gap states as a consequence of the Andreev tunneling through the impurity state, which involves the formation or breakup of a Cooper pair. Due to the low carrier density in NaAlSi, the in-gap state is tunable by controlling the STM tip-sample distance. Under strong external magnetic fields, the impurity state shows Zeeman splitting when it is located near the Fermi level. Our findings not only demonstrate the Andreev tunneling involving single electronic state but also provide new insights for understanding the spatially dependent in-gap states in low carrier density superconductors.

5.
J Cell Physiol ; 239(8): e31295, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38747637

RESUMEN

Critical reprogramming factors resided predominantly in the oocyte or male pronucleus can enhance the efficiency or the quality of induced pluripotent stem cells (iPSCs) induction. However, few reprogramming factors exist in the male pronucleus had been verified. Here, we demonstrated that granulin (Grn), a factor enriched specifically in male pronucleus, can significantly improve the generation of iPSCs from mouse fibroblasts. Grn is highly expressed on Day 1, Day 3, Day 14 of reprogramming induced by four Yamanaka factors and functions at the initial stage of reprogramming. Transcriptome analysis indicates that Grn can promote the expression of lysosome-related genes, while inhibit the expression of genes involved in DNA replication and cell cycle at the early reprogramming stage. Further verification determined that Grn suppressed cell proliferation due to the arrest of cell cycle at G2/M phase. Moreover, ectopic Grn can enhance the lysosomes abundance and rescue the efficiency reduction of reprogramming resulted from lysosomal protease inhibition. Taken together, we conclude that Grn serves as an activator for somatic cell reprogramming through mitigating cell hyperproliferation and promoting the function of lysosomes.


Asunto(s)
Proliferación Celular , Reprogramación Celular , Fibroblastos , Células Madre Pluripotentes Inducidas , Lisosomas , Animales , Lisosomas/metabolismo , Reprogramación Celular/genética , Masculino , Ratones , Células Madre Pluripotentes Inducidas/metabolismo , Fibroblastos/metabolismo , Granulinas , Progranulinas/metabolismo , Progranulinas/genética , Núcleo Celular/metabolismo
6.
Dev Genes Evol ; 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39190085

RESUMEN

The chromodomain helicase DNA binding domain 2 (CHD2) gene is an ATPase and a member of the SNF2-like family of helicase-related enzymes. CHD2 plays critical roles in human brain development and function, and homozygous mutation of Chd2 in mice results in perinatal lethality. To further elucidate the effects of chd2, we used CRISPR/Cas9 to create two chd2-knockout strains (fdu901, 11,979-11982delGGGT, and fdu902, 27350delG) in zebrafish. We found that the deformity and mortality rates of fdu901 and fdu902 were higher than those of the wild type. Developmental delay was more obvious and embryo mortality was higher in fdu901 than in fdu902. However, the embryo deformity rate in fdu902 was higher than that in fdu901. Although there were no significant differences in behavior between the two knockout zebrafish and wild-type zebrafish at 7 days post fertilization (dpf), fdu901 and fdu902 zebrafish showed different alterations. The excitability of fdu902 was higher than that of fdu901. Overall, our data demonstrate that two homozygous chd2 knockout mutations were survivable and could be stably inherited and that fdu901 and fdu902 zebrafish differed in behavior and morphology. These two models might be good tools for understanding the functions of the different domains of chd2.

7.
J Gen Virol ; 105(5)2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38757942

RESUMEN

Since its discovery in 1965, our understanding of the hepatitis B virus (HBV) replication cycle and host immune responses has increased markedly. In contrast, our knowledge of the molecular biology of hepatitis delta virus (HDV), which is associated with more severe liver disease, is less well understood. Despite the progress made, critical gaps remain in our knowledge of HBV and HDV replication and the mechanisms underlying viral persistence and evasion of host immunity. The International HBV Meeting is the leading annual scientific meeting for presenting the latest advances in HBV and HDV molecular virology, immunology, and epidemiology. In 2023, the annual scientific meeting was held in Kobe, Japan and this review summarises some of the advances presented at the Meeting and lists gaps in our knowledge that may facilitate the development of new therapies.


Asunto(s)
Virus de la Hepatitis B , Hepatitis B , Virus de la Hepatitis Delta , Replicación Viral , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/fisiología , Virus de la Hepatitis B/inmunología , Humanos , Virus de la Hepatitis Delta/genética , Virus de la Hepatitis Delta/fisiología , Hepatitis B/virología , Hepatitis B/inmunología , Biología Molecular , Japón , Hepatitis D/virología , Interacciones Huésped-Patógeno/inmunología , Interacciones Huésped-Patógeno/genética
8.
J Clin Immunol ; 44(6): 137, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38805163

RESUMEN

The pre BCR complex plays a crucial role in B cell production, and its successful expression marks the B cell differentiation from the pro-B to pre-B. The CD79a and CD79b mutations, encoding Igα and Igß respectively, have been identified as the cause of autosomal recessive agammaglobulinemia (ARA). Here, we present a case of a patient with a homozygous CD79a mutation, exhibiting recurrent respiratory infections, diarrhea, growth and development delay, unique facial abnormalities and microcephaly, as well as neurological symptoms including tethered spinal cord, sacral canal cyst, and chronic enteroviral E18 meningitis. Complete blockade of the early B cell development in the bone marrow of the patient results in the absence of peripheral circulating mature B cells. Whole exome sequencing revealed a Loss of Heterozygosity (LOH) of approximately 19.20Mb containing CD79a on chromosome 19 in the patient. This is the first case of a homozygous CD79a mutation caused by segmental uniparental diploid (UPD). Another key outcome of this study is the effective management of long-term chronic enteroviral meningitis using a combination of intravenous immunoglobulin (IVIG) and fluoxetine. This approach offers compelling evidence of fluoxetine's utility in treating enteroviral meningitis, particularly in immunocompromised patients.


Asunto(s)
Agammaglobulinemia , Cromosomas Humanos Par 19 , Fluoxetina , Disomía Uniparental , Humanos , Fluoxetina/uso terapéutico , Cromosomas Humanos Par 19/genética , Agammaglobulinemia/genética , Agammaglobulinemia/tratamiento farmacológico , Antígenos CD79/genética , Masculino , Infecciones por Enterovirus/tratamiento farmacológico , Infecciones por Enterovirus/genética , Mutación/genética , Inmunoglobulinas Intravenosas/uso terapéutico , Femenino
9.
Anal Chem ; 96(33): 13429-13437, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39106034

RESUMEN

Ion mobility spectrometry (IMS) is a compact and sensitive trace gas analysis instrument that ionizes the sample into ions for detection. Typically, an ion gate is used to cut the continuous ion beam into ion packets for separation and detection. However, commonly used ion gates suffer from complex structures or low ion transmission rates, making the gateless IMS a viable alternative. In this study, an IMS based on a pulsed photoelectric effect ionization source was designed. The photoelectrons were generated by irradiating a photoelectric material with a back-illuminated pulsed xenon lamp. This allows for low-energy photoelectron generation and the production of simple reactant ions (O2-(H2O)n) and thus negative product ions. The photoelectron current generated by this ionization source was analyzed, which can reach an intensity of a few microamperes and can be converted into an ion signal exceeding 10 nA. The introduction of the pulsed photoelectric effect ionization source makes it possible to generate separate ion packets and complete ion injection when a constant electric field is maintained in the ionization region. And with an assisted pulsed electric field in the ionization region, the resolving power of the system can be effectively improved to 1.85 times that of the constant electric field. The IMS developed in this study was used for the detection of common volatile hazardous chemicals, yielding effective results. The detection limit for phenol was below 1 ppb, and the dynamic response range exceeded 1 order of magnitude, which implies the potential applications of this IMS to detect substances with high electron affinity, such as explosives detection in public safety.

10.
Small ; 20(8): e2306382, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37828635

RESUMEN

Amelioration of nickel-cobalt layered double hydroxides (NiCo-LDH) with a high specific theoretical capacitance is of great desire for high-power supercapacitors. Herein, a molybdenum (Mo) doping strategy is proposed to improve the charge-storage performance of NiCo-LDH nanosheets growing on carbon cloth (CC) via a rapid microwave process. The regulation of the electronic structure and oxygen vacancy of the LDH is consolidated by the density functional theory (DFT) calculation, which demonstrates that Mo doping narrows the band gap, reduces the formation energy of hydroxyl vacancies, and promotes ionic and charge transfer as well as electrolyte adsorption on the electrode surface. The optimal Mo-doped NiCo-LDH electrode (MoNiCo-LDH-0.05/CC) has an amazing specific capacity of 471.1 mA h g-1 at 1 A g-1 , and excellent capacity retention of 84.8% at 32 A g-1 , far superior to NiCo-LDH/CC (258.3 mA h g-1 and 76.4%). The constructed hybrid supercapacitor delivers an energy density of 103.3 W h kg-1 at a power density of 750 W kg-1 and retains the cycle retention of 85.2% after 5000 cycles. Two assembled devices in series can drive thirty LED lamps, revealing a potential application prospect of the rationally synthesized MoNiCo-LDH/CC as an energy-storage electrode material.

11.
Mol Carcinog ; 63(5): 859-873, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38353359

RESUMEN

Breast cancer has become the most commonly diagnosed cancer. Heterogeneous nuclear ribonucleoprotein C (HNRNPC), a reader of N6-methyladenosine (m6A), has been observed to be upregulated in various types of cancer. Nevertheless, the role of HNRNPC in breast cancer and whether it is regulated by m6A modification deserve further investigation. The expression of HNRNPC in breast cancer was examined by quantitative real-time polymerase chain reaction and western blot analysis. RNA immunoprecipitation was performed to validate the binding relationships between HNRNPC and WD repeat domain 77 (WDR77). The effects of HNRNPC and m6A regulators on WDR77 were investigated by actinomycin D assay. The experiments in vivo were conducted in xenograft models. In this research, we found that HNRNPC was highly expressed in breast cancer, and played a crucial role in cell growth, especially in the luminal subtype. HNRNPC could combine and stabilize WDR77 mRNA. WDR77 successively drove the G1/S phase transition in the cell cycle and promoted cell proliferation. Notably, this regulation axis was closely tied to the m6A modification status of WDR77 mRNA. Overall, a critical regulatory mechanism was identified, as well as promising targets for potential treatment strategies for luminal breast cancer.


Asunto(s)
Neoplasias de la Mama , Ribonucleoproteína Heterogénea-Nuclear Grupo C , Femenino , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Ciclo Celular/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo C/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo C/metabolismo , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , ARN Mensajero/genética , Factores de Transcripción/genética , Adenosina
12.
J Virol ; 97(7): e0032823, 2023 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-37338350

RESUMEN

Hepatitis B virus (HBV) chronically infects approximately 300 million people worldwide, and permanently repressing transcription of covalently closed circular DNA (cccDNA), the episomal viral DNA reservoir, is an attractive approach toward curing HBV. However, the mechanism underlying cccDNA transcription is only partially understood. In this study, by illuminating cccDNA of wild-type HBV (HBV-WT) and transcriptionally inactive HBV that bears a deficient HBV X gene (HBV-ΔX), we found that the HBV-ΔX cccDNA more frequently colocalizes with promyelocytic leukemia (PML) bodies than that of HBV-WT cccDNA. A small interfering RNA (siRNA) screen targeting 91 PML body-related proteins identified SMC5-SMC6 localization factor 2 (SLF2) as a host restriction factor of cccDNA transcription, and subsequent studies showed that SLF2 mediates HBV cccDNA entrapment in PML bodies by interacting with the SMC5/6 complex. We further showed that the region of SLF2 comprising residues 590 to 710 interacts with and recruits the SMC5/6 complex to PML bodies, and the C-terminal domain of SLF2 containing this region is necessary for repression of cccDNA transcription. Our findings shed new light on cellular mechanisms that inhibit HBV infection and lend further support for targeting the HBx pathway to repress HBV activity. IMPORTANCE Chronic HBV infection remains a major public health problem worldwide. Current antiviral treatments rarely cure the infection, as they cannot clear the viral reservoir, cccDNA, in the nucleus. Therefore, permanently silencing HBV cccDNA transcription represents a promising approach for a cure of HBV infection. Our study provides new insights into the cellular mechanisms that restrict HBV infection, revealing the role of SLF2 in directing HBV cccDNA to PML bodies for transcriptional repression. These findings have important implications for the development of antiviral therapies against HBV.


Asunto(s)
Hepatitis B , Leucemia , Humanos , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/metabolismo , ADN Circular/genética , ADN Circular/metabolismo , Antivirales/farmacología , ADN Viral/genética , ADN Viral/metabolismo , Proteína de la Leucemia Promielocítica/genética , Proteína de la Leucemia Promielocítica/metabolismo , Replicación Viral/genética , Proteínas Cromosómicas no Histona/metabolismo , Proteínas de Ciclo Celular/metabolismo
13.
J Virol ; 97(1): e0171722, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36475867

RESUMEN

Hepatitis B virus (HBV) infection remains a public health problem worldwide. Persistent HBV infection relies on active transcription of the covalently closed circular DNA (cccDNA) in hepatocytes, which is less understood at the single-cell level. In this study, we isolated primary human hepatocytes from liver-humanized FRG mice infected with HBV and examined cccDNA transcripts in single cells based on 5' end sequencing. Our 5' transcriptome sequencing (RNA-seq) analysis unambiguously assigns different viral transcripts with overlapping 3' sequences and quantitatively measures viral transcripts for structural genes (3.5 kb, 2.4 kb, and 2.1 kb) and the nonstructural X gene (0.7 kb and related) in single cells. We found that an infected cell either can generate all viral transcripts, signifying active transcription, or presents only transcripts from the X gene and its associated enhancer I domain and no structural gene transcripts. Results from cell infection assays with recombinant HBV show that nonproductive transcription of cccDNA can be activated by incoming virus through superinfection. Moreover, upon HBV infection, cccDNA apparently can be transcribed in the absence of HBx and produces HBx, needed for productive transcription of other viral genes. These results shed new light on cccDNA transcription at the single-cell level and provide insights useful for improving the treatment strategy against chronic HBV infection. IMPORTANCE Hepatitis B virus (HBV) infection can be effectively suppressed but rarely cured by available drugs. Chronic HBV infection is based on persistence of covalently closed circular DNA (cccDNA) and continuous infection and reinfection with HBV in the liver. Understanding transcriptional regulation of cccDNA will help to achieve permanent transcriptional silencing, i.e., functional cure of HBV. In our study, we found that an infected cell either can generate all viral transcripts, signifying active transcription, or presents only transcripts from the X gene and its associated enhancer I domain and no structural gene transcripts. The nonproductive transcription of cccDNA can be activated by incoming virus through superinfection. Upon an infection, cccDNA apparently can be transcribed in the absence of HBx to produce HBx, necessary for subsequent transcription of other HBV genes. Our studies shed new light on the mechanism of HBV infection and may have implications for a functional cure regimen for HBV.


Asunto(s)
ADN Circular , Hepatitis B Crónica , Sobreinfección , Animales , Humanos , Ratones , ADN Circular/genética , ADN Viral/genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/genética , Replicación Viral/genética , Hepatocitos , Proteínas Reguladoras y Accesorias Virales/genética
14.
Neurochem Res ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916813

RESUMEN

Dysfunction of Schwann cells, including cell apoptosis, autophagy inhibition, dedifferentiation, and pyroptosis, is a pivotal pathogenic factor in induced diabetic peripheral neuropathy (DPN). Histone deacetylases (HDACs) are an important family of proteins that epigenetically regulate gene transcription by affecting chromatin dynamics. Here, we explored the effect of HDAC1 on high glucose-cultured Schwann cells. HDAC1 expression was increased in diabetic mice and high glucose-cultured RSC96 cells, accompanied by cell apoptosis. High glucose also increased the mitochondrial pathway apoptosis-related Bax/Bcl-2 and cleaved caspase-9/caspase-9 ratios and decreased endoplasmic reticulum response-related GRP78, CHOP, and ATF4 expression in RSC96 cells (P < 0.05). Furthermore, overexpression of HDAC1 increased the ratios of Bax/Bcl-2, cleaved caspase-9/caspase-9, and cleaved caspase-3 and reduced the levels of GRP78, CHOP, and ATF4 in RSC96 cells (P < 0.05). In contrast, knockdown of HDAC1 inhibited high glucose-promoted mitochondrial pathway apoptosis and suppressed the endoplasmic reticulum response. Moreover, RNA sequencing revealed that U4 spliceosomal RNA was significantly reduced in HDAC1-overexpressing RSC96 cells. Silencing of U4 spliceosomal RNA led to an increase in Bax/Bcl-2 and cleaved caspase-9 and a decrease in CHOP and ATF4. Conversely, overexpression of U4 spliceosomal RNA blocked HDAC1-promoted mitochondrial pathway apoptosis and inhibited the endoplasmic reticulum response. In addition, alternative splicing analysis of HDAC1-overexpressing RSC96 cells showed that significantly differential intron retention (IR) of Rpl21, Cdc34, and Mtmr11 might be dominant downstream targets that mediate U4 deficiency-induced Schwann cell dysfunction. Taken together, these findings indicate that HDAC1 promotes mitochondrial pathway-mediated apoptosis and inhibits the endoplasmic reticulum stress response in high glucose-cultured Schwann cells by decreasing the U4 spliceosomal RNA/IR of Rpl21, Cdc34, and Mtmr11.

15.
Langmuir ; 40(1): 687-695, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38124669

RESUMEN

Fluid transport in kerogen is mainly diffusion-driven, while its dependence on pore informatics is still poorly understood. It is challenging for experiments to identify the effect of pore informatics (such as pore connectivity and tortuosity) on fluid transport therein. Therefore, in this work, we use molecular dynamics simulations to study methane transport behaviors in amorphous kerogen matrices with broad pore properties. The pore properties including porosity, pore connectivity, pore size, and diffusive tortuosity are characterized. Next, self-diffusion coefficients in the connected pores (DeffS) and in the total pores without distinguishing its connectivity (DtotS) are calculated in all the kerogen matrices based on the free volume theory. We find that both DeffS and DtotS exponentially decreases with methane loading with two controlled parameters: fitting constant αeff and DeffS(0) (DeffS at infinitely small loading) for DeffS and fitting constant αtot and DtotS(0) (DtotS at infinitely small loading) for DtotS. However, in the kerogen models with relatively low pore connectivity, αeff and αtot as well as DeffS(0) and DtotS(0) can be quite different, inducing the different estimations of DeffS and DtotS. Since methane in the unconnected pores does not contribute to the actual transport, it is important to recognize connected pores when evaluating the fluid transport in kerogen. On the other hand, DeffS(0) strongly depends on the effective limiting pore size (rlim_eff) of the dominant flow path and effective diffusive tortuosity (τeff), in which DeffS(0) linearly increases with (rlim_eff/τeff)2. We also find that αeff is a multivariable function of ϕeff, τeff, and rlim_eff, but their generalized relation requires more data to obtain. This work provides important insights into fluid transport in kerogen based on the kerogen pore informatics, which are important to shale gas development.

16.
Environ Sci Technol ; 58(5): 2434-2445, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38265760

RESUMEN

Source characteristics and health risks of indoor organophosphate esters (OPEs) are limited by the lack of knowledge on emission processes. This study attempted to integrate the contents and emissions of OPEs from indoor building materials to assess human health effects. Thirteen OPEs were investigated in 80 pieces of six categories of building materials. OPEs are ubiquitous in the building materials and ∑13OPE contents varied significantly (p < 0.05) from 72.8 ng/g (seam agent) to 109,900 ng/g (wallpaper). Emission characteristics of OPEs from the building materials were examined based on a microchamber method. Depending on the sample category, the observed initial area-specific emission rates of ∑13OPEs varied from 154 ng/m2/h (carpet) to 2760 ng/m2/h (wooden floorboard). Moreover, the emission rate model was developed to predict the release levels of individual OPEs, quantify source contributions, and assess associated exposure risks. Source apportionments of indoor OPEs exhibited heterogeneities in multiple environmental media. The joint OPE contribution of wallpaper and wooden floorboard to indoor dust was up to 94.8%, while latex paint and wooden floorboard were the main OPE contributors to indoor air (54.2%) and surface (76.1%), respectively. Risk assessment showed that the carcinogenic risks of tris(2-chloroethyl) phosphate (3.35 × 10-7) were close to the acceptable level (1 × 10-6) and deserved special attention.


Asunto(s)
Monitoreo del Ambiente , Retardadores de Llama , Humanos , Ésteres/análisis , Retardadores de Llama/análisis , China , Organofosfatos/análisis , Polvo/análisis , Materiales de Construcción
17.
Biotechnol Appl Biochem ; 71(4): 733-740, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38494670

RESUMEN

Plasma circulating P-selectin glycoprotein ligand-1 (PSGL-1) levels and its clinical correlation in patients with epithelial ovarian cancer (EOC) are unknown. The study determined plasma PSGL-1 levels in EOC patients and investigated its relationship with clinicopathological factors and prognosis. Plasma PSGL-1 levels were measured using ELISA in 69 patients with EOC, 34 patients with benign ovarian cystadenoma, and 36 healthy controls. Subsequently, the relationship between PSGL-1 levels and clinicopathological characteristics of patients, as well as the prognosis of EOC patients, was examined. Additionally, the specificity and sensitivity of plasma PSGL-1 were assessed through ROC curve analysis. Plasma PSGL-1 was upregulated in EOC patients compared with healthy subjects and/or patients with benign ovarian cystadenoma (p < 0.01). Elevated levels of PSGL-1 in the plasma were positively associated with advanced FIGO stage (p < 0.001), tumor size (p = 0.001), tumor metastasis (p = 0.036), and tumor recurrence (p = 0.013), while was negatively correlated with residual tumor size (p < 0.001). Kaplan-Meier survival analysis showed that high plasma PSGL-1 levels were associated with progression-free survival (p = 0.0345). In univariate and multivariate Cox regression analyses, PSGL-1 (HR = 1.456, p = 0.009) was an independent prognostic marker. Plasma PSGL-1 levels distinguished EOC patients and healthy individuals (AUC = 0.905), patients at late and early FIGO stages (AUC = 0.886), and metastatic and non-metastatic EOC (AUC = 0.722). The expression of plasma PSGL-1 is significantly increased in patients with EOC, serving as a reliable biomarker to differentiate between healthy individuals and those with EOC. Furthermore, PSGL-1 in patients is correlated with prognostic indicators, such as advanced FIGO stage, tumor lymph node metastasis, and progression-free survival.


Asunto(s)
Carcinoma Epitelial de Ovario , Glicoproteínas de Membrana , Estadificación de Neoplasias , Neoplasias Ováricas , Humanos , Femenino , Persona de Mediana Edad , Neoplasias Ováricas/patología , Neoplasias Ováricas/sangre , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/diagnóstico , Carcinoma Epitelial de Ovario/sangre , Carcinoma Epitelial de Ovario/patología , Carcinoma Epitelial de Ovario/mortalidad , Carcinoma Epitelial de Ovario/diagnóstico , Glicoproteínas de Membrana/sangre , Metástasis de la Neoplasia , Adulto , Biomarcadores de Tumor/sangre , Anciano , Pronóstico , Tasa de Supervivencia
18.
J Thromb Thrombolysis ; 57(1): 143-154, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37548902

RESUMEN

The aim of this study was to identify the optimal anti-platelet therapy in older acute coronary syndrome (ACS) patients with a mean age ≥ 60 years by comparing the efficacy and safety of different anti-platelet therapies. The selection of antiplatelet therapy in older patients with ACS is a clinical challenge. Numerous evidences indicate that the de-escalation of dual anti-platelet therapy (DAPT) or P2Y12 inhibitor monotherapy may reduce bleeding risk without increasing thrombotic events. However, there is a lack of systematic reviews and optimal strategy analysis regarding older ACS patients. Randomized controlled trials (RCTs) of anti-platelet therapy in older ACS patients were identified. Major adverse cardiovascular events (MACE) were the primary outcome. Secondary outcomes included all death, cardiovascular death, myocardial infarction, stroke, stent thrombosis, and trial-defined major bleeding. Frequentist and Bayesian network meta-analyses were conducted. Treatments were ranked on posterior probability. Summary odds ratios (ORs) were estimated using Bayesian network meta-analysis. A total of 12 RCTs including 59,284 older ACS patients treated with five anti-platelet strategies were included. Ticagrelor monotherapy after 3 months DAPT was comparable to the other strategies (OR 0.73; 95% CI 0.32-1.6) in terms of MACE risk. Additionally, P score analysis and SUCRA Bayesian analysis showed that it was the most beneficial treatment for all deaths, cardiovascular death and revascularization. For safety, although there was no significant difference in direct comparisons, both SUCRA Bayesian (0.806) and P score (0.519) analysis suggested that ticagrelor monotherapy was the safest strategy. The current evidence demonstrated that ticagrelor monotherapy after 3 months DAPT may be a promising approach for achieving a more favorable balance between risk and benefit for older ACS patients, with a relatively low bleeding risk and without an increased risk of MACE events. Moreover, it remains the preferred option for clinical outcomes such as all death, CV death and revascularization. Further high-quality and long-term studies are required to validate anti-platelet therapies among older ACS patients.


Asunto(s)
Síndrome Coronario Agudo , Intervención Coronaria Percutánea , Trombosis , Humanos , Anciano , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/efectos adversos , Ticagrelor/uso terapéutico , Síndrome Coronario Agudo/tratamiento farmacológico , Metaanálisis en Red , Ensayos Clínicos Controlados Aleatorios como Asunto , Revisiones Sistemáticas como Asunto , Hemorragia/inducido químicamente , Hemorragia/tratamiento farmacológico , Trombosis/tratamiento farmacológico , Resultado del Tratamiento
19.
Cell Mol Life Sci ; 80(8): 218, 2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37470863

RESUMEN

BACKGROUND: Abundantly expressed factors in the oocyte cytoplasm can remarkably reprogram terminally differentiated germ cells or somatic cells into totipotent state within a short time. However, the mechanism of the different factors underlying the reprogramming process remains uncertain. METHODS: On the basis of Yamanaka factors OSKM induction method, MEF cells were induced and reprogrammed into iPSCs under conditions of the oocyte-derived factor Wdr82 overexpression and/or knockdown, so as to assess the reprogramming efficiency. Meanwhile, the cellular metabolism was monitored and evaluated during the reprogramming process. The plurpotency of the generated iPSCs was confirmed via pluripotent gene expression detection, embryoid body differentiation and chimeric mouse experiment. RESULTS: Here, we show that the oocyte-derived factor Wdr82 promotes the efficiency of MEF reprogramming into iPSCs to a greater degree than the Yamanaka factors OSKM. The Wdr82-expressing iPSC line showed pluripotency to differentiate and transmit genetic material to chimeric offsprings. In contrast, the knocking down of Wdr82 can significantly reduce the efficiency of somatic cell reprogramming. We further demonstrate that the significant suppression of oxidative phosphorylation in mitochondria underlies the molecular mechanism by which Wdr82 promotes the efficiency of somatic cell reprogramming. Our study suggests a link between mitochondrial energy metabolism remodeling and cell fate transition or stem cell function maintenance, which might shed light on the embryonic development and stem cell biology.


Asunto(s)
Proteínas Cromosómicas no Histona , Células Madre Pluripotentes Inducidas , Animales , Ratones , Diferenciación Celular/genética , Reprogramación Celular/genética , Glucólisis/genética , Mitocondrias/metabolismo , Fosforilación Oxidativa , Repeticiones WD40 , Proteínas Cromosómicas no Histona/genética
20.
Bioelectromagnetics ; 45(2): 82-93, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37860924

RESUMEN

Conductive dental implants are commonly used in restorative therapy to replace missing teeth in patients. Ensuring the radiofrequency (RF) safety of these patients is crucial when performing 7 T magnetic resonance scans of their heads. This study aimed to investigate RF-induced heating inside the human head with dental implants at 7 T. Dental implants and their attachments were fabricated and integrated into an anatomical head model, creating different measurement configurations (MCs). Numerical simulations were conducted using a 7 T transmit coil loaded with the anatomical head model, both with and without dental implants. The maximum temperatures inside the head for various MCs were computed using the maximum permissible input powers (MPIPs) obtained without dental implants and compared with published limits. Additionally, the MPIPs with dental implants were calculated for scenarios where the temperature limits were exceeded. The maximum temperatures observed inside the head ranged from 38.4°C to 39.6°C. The MPIPs in the presence of dental implants were 81.9%-97.3% of the MPIPs in the absence of dental implants for scenarios that exceeded the regulatory limit. RF-induced heating effect of the dental implants was not significant. The safe scanning condition in terms of RF exposure was achievable for patients with dental implants. For patients with conductive dental implants of unknown configuration, it is recommended to reduce the input power by 18.1% of MPIP without dental implants to ensure RF safety.


Asunto(s)
Implantes Dentales , Calor , Humanos , Calefacción , Temperatura , Imagen por Resonancia Magnética , Ondas de Radio/efectos adversos , Fantasmas de Imagen
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA