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1.
J Hepatol ; 80(1): 41-52, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37858684

RESUMEN

BACKGROUND & AIMS: HBsAg loss is only observed in a small proportion of patients with chronic hepatitis B (CHB) who undergo interferon treatment. Investigating the host factors crucial for functional cure of CHB can aid in identifying individuals who would benefit from peginterferon-α (Peg-IFNα) therapy. METHODS: We conducted a genome-wide association study (GWAS) by enrolling 48 patients with CHB who achieved HBsAg loss after Peg-IFNα treatment and 47 patients who didn't. In the validation stage, we included 224 patients, of whom 90 had achieved HBsAg loss, to validate the identified significant single nucleotide polymorphisms. To verify the functional involvement of the candidate genes identified, we performed a series of in vitro and in vivo experiments. RESULTS: GWAS results indicated a significant association between the rs7519753 C allele and serum HBsAg loss in patients with CHB after Peg-IFNα treatment (p = 4.85 × 10-8, odds ratio = 14.47). This association was also observed in two independent validation cohorts. Expression quantitative trait locus analysis revealed higher hepatic TP53BP2 expression in individuals carrying the rs7519753 C allele (p = 2.90 × 10-6). RNA-sequencing of liver biopsies from patients with CHB after Peg-IFNα treatment revealed that hepatic TP53BP2 levels were significantly higher in the HBsAg loss group compared to the HBsAg persistence group (p = 0.035). In vitro and in vivo experiments demonstrated that loss of TP53BP2 decreased interferon-stimulated gene levels and the anti-HBV effect of IFN-α. Mechanistically, TP53BP2 was found to downregulate SOCS2, thereby facilitating JAK/STAT signaling. CONCLUSION: The rs7519753 C allele is associated with elevated hepatic TP53BP2 expression and an increased probability of serum HBsAg loss post-Peg-IFNα treatment in patients with CHB. TP53BP2 enhances the response of the hepatocyte to IFN-α by suppressing SOCS2 expression. IMPACT AND IMPLICATIONS: Chronic hepatitis B (CHB) remains a global public health issue. Although current antiviral therapies are more effective in halting disease progression, only a few patients achieve functional cure for hepatitis B with HBsAg loss, highlighting the urgent need for a cure for CHB. This study revealed that the rs7519753 C allele, which is associated with high expression of hepatic TP53BP2, significantly increases the likelihood of serum HBsAg loss in patients with CHB undergoing Peg-IFNα treatment. This finding not only provides a promising predictor for HBsAg loss but identifies a potential therapeutic target for Peg-IFNα treatment. We believe our results are of great interest to a wide range of stakeholders based on their potential clinical implications.


Asunto(s)
Antivirales , Hepatitis B Crónica , Humanos , Antivirales/uso terapéutico , Antígenos de Superficie de la Hepatitis B/genética , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/genética , Estudio de Asociación del Genoma Completo , Quimioterapia Combinada , Interferón-alfa/farmacología , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Antígenos e de la Hepatitis B , Proteínas Recombinantes/uso terapéutico , Resultado del Tratamiento , ADN Viral/genética , Proteínas Reguladoras de la Apoptosis
2.
BMC Med ; 22(1): 271, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926881

RESUMEN

BACKGROUND: To evaluate the neurological alterations induced by Omicron infection, to compare brain changes in chronic insomnia with those in exacerbated chronic insomnia in Omicron patients, and to examine individuals without insomnia alongside those with new-onset insomnia. METHODS: In this study, a total of 135 participants were recruited between January 11 and May 4, 2023, including 26 patients with chronic insomnia without exacerbation, 24 patients with chronic insomnia with exacerbation, 40 patients with no sleep disorder, and 30 patients with new-onset insomnia after infection with Omicron (a total of 120 participants with different sleep statuses after infection), as well as 15 healthy controls who were never infected with Omicron. Neuropsychiatric data, clinical symptoms, and multimodal magnetic resonance imaging data were collected. The gray matter thickness and T1, T2, proton density, and perivascular space values were analyzed. Associations between changes in multimodal magnetic resonance imaging findings and neuropsychiatric data were evaluated with correlation analyses. RESULTS: Compared with healthy controls, gray matter thickness changes were similar in the patients who have and do not have a history of chronic insomnia groups after infection, including an increase in cortical thickness near the parietal lobe and a reduction in cortical thickness in the frontal, occipital, and medial brain regions. Analyses showed a reduced gray matter thickness in patients with chronic insomnia compared with those with an aggravation of chronic insomnia post-Omicron infection, and a reduction was found in the right medial orbitofrontal region (mean [SD], 2.38 [0.17] vs. 2.67 [0.29] mm; P < 0.001). In the subgroups of Omicron patients experiencing sleep deterioration, patients with a history of chronic insomnia whose insomnia symptoms worsened after infection displayed heightened medial orbitofrontal cortical thickness and increased proton density values in various brain regions. Conversely, patients with good sleep quality who experienced a new onset of insomnia after infection exhibited reduced cortical thickness in pericalcarine regions and decreased proton density values. In new-onset insomnia patients post-Omicron infection, the thickness in the right pericalcarine was negatively correlated with the Self-rating Anxiety Scale (r = - 0.538, P = 0.002, PFDR = 0.004) and Self-rating Depression Scale (r = - 0.406, P = 0.026, PFDR = 0.026) scores. CONCLUSIONS: These findings help us understand the pathophysiological mechanisms involved when Omicron invades the nervous system and induces various forms of insomnia after infection. In the future, we will continue to pay attention to the dynamic changes in the brain related to insomnia caused by Omicron infection.


Asunto(s)
COVID-19 , Imagen por Resonancia Magnética , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , COVID-19/complicaciones , COVID-19/diagnóstico por imagen , COVID-19/patología , Masculino , Femenino , Persona de Mediana Edad , Adulto , Trastornos del Inicio y del Mantenimiento del Sueño/diagnóstico por imagen , Calidad del Sueño , SARS-CoV-2 , Neuroimagen/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Imagen Multimodal/métodos , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Anciano
3.
J Nanobiotechnology ; 22(1): 355, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38902678

RESUMEN

BACKGROUND: Cancer recurrence following surgical resection is a major cause of treatment failure. Finding effective methods to prevent postoperative recurrence and wound infection is an important component of successful surgery. With the development of new nanotechnology, more treatment options have been provided for postoperative adjuvant therapy. This study presents an innovative hydrogel system that stimulates tumoricidal immunity after surgical resection of non-small cell lung cancer (NSCLC) and prevents cancer relapse. RESULTS: The hydrogel system is based on the excellent photothermal conversion performance of single-atom platinum (CN-Pt) along with the delivery and release of the chemotherapy drug, gemcitabine (GEM). The system is coated onto the wound surface after tumor removal with subsequent near-infrared (NIR) photothermal therapy, which efficiently induces necroptosis of residual cancer cells, amplifies the levels of damage-associated molecular patterns (DAMPs), and increases the number of M1 macrophages. The significantly higher levels of phagocytic macrophages enhance tumor immunogenicity and sensitize cancer cells to CD8 + T-cell immunity to control postoperative recurrence, which has been verified using an animal model of postoperative lung cancer recurrence. The CN-Pt-GEM-hydrogel with NIR can also inhibit postoperative wound infection. CONCLUSIONS: These findings introduce an alternative strategy for supplementing antitumor immunity in patients undergoing resection of NSCLC tumors. The CN-Pt-GEM-hydrogel with the NIR system also exhibits good biosafety and may be adaptable for clinical application in relation to tumor resection surgery, wound tissue filling, infection prevention, and recurrence prevention.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Desoxicitidina , Gemcitabina , Hidrogeles , Neoplasias Pulmonares , Necroptosis , Animales , Ratones , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Desoxicitidina/uso terapéutico , Hidrogeles/química , Humanos , Necroptosis/efectos de los fármacos , Recurrencia Local de Neoplasia , Línea Celular Tumoral , Inmunoterapia/métodos , Terapia Fototérmica/métodos , Infección de Heridas/prevención & control , Infección de Heridas/tratamiento farmacológico , Macrófagos/efectos de los fármacos , Ratones Endogámicos C57BL , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos
4.
Inorg Chem ; 62(48): 19749-19757, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-37983184

RESUMEN

Lanthanide-containing polyoxometalate-based metal-organic frameworks (POMOFs) not only enjoy intriguing architectures but also have good application prospects as catalysts. Herein, three novel three-dimensional (3D) POMOFs with the formulas of {H[Ln3(2,6-pydc)2(H2O)10(MnMo9O32)]·2H2O}n (Ln = La(1), Pr(2), Nd(3)) have been synthesized based on Waugh-type [MnMo9O32]6- anions and pyridine-2,6-dicarboxylate (2,6-H2pydc). Compounds 1-3 are isomorphic, and there are two kinds of one-dimensional (1D) helical chains with opposite handedness staggered into two-dimensional (2D) layers. Interestingly, the coordinated L- and R-[MnMo9O32]6- anions are encapsulated in 1D chains with the same chirality and are further expanded into 3D structures. The catalytic tests indicate that compounds 1-3 exhibit high-efficiency heterogeneous catalytic activity in the oxidative desulfurization reaction for catalyzing the oxidation of sulfides to sulfoxides using tert-butyl hydrogen peroxide (TBHP) as the oxidant. Moreover, a series of control experiments have been conducted to investigate the influence of various parameters such as temperature, time, solvent, catalyst, and substrate on the reaction. Significantly, compound 2, as an example, exhibits good reusability and structural stability in the oxidative desulfurization reaction. It is worth noting that investigations on the oxidative desulfurization of [MnMo9O32]6- anions are scarce. Moreover, their electrochemical properties are also explored.

5.
Inorg Chem ; 62(14): 5780-5790, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-36976898

RESUMEN

Achieving long-term stable deep desulfurization at room temperature and recovering high value-added sulfone products is a challenge at present. Herein, a series of catalysts [Cnmim]5VW12O40Br (CnVW12, 1-alkyl-3-methylimidazolium bromide tungstovanadate, n = 4, 8, 16) were presented for the room temperature catalytic oxidation of dibenzothiophene (DBT) and its derivatives. Factors affecting the reaction process, such as the amount of catalyst, oxidant, and temperature, were systematically discussed. C16VW12 showed higher catalytic performance, and 100% conversion and selectivity could be achieved in 50 min with only 10 mg. The mechanism study showed that the hydroxyl radical was the active radical in the reaction. Benefiting from the "polarity strategy", the sulfone product accumulated after 23 cycles in a C16VW12 system, and the yield and purity were about 84% and 100%, respectively.

6.
J Environ Manage ; 325(Pt B): 116558, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36302299

RESUMEN

Tile-back type slopes comprise ephemeral gullies (EGs) and hillslopes; they are a unique and widely distributed micro-landform in the Loess Plateau region of China. Gully erosion from these landforms is a serious issue, but the micro-landform makes the erosion process and its estimation complex. Quantifying soil erosion processes and their distribution characteristics at different positions on tile-back type slopes will provide a clearer picture for ecological restoration to control further soil degradation. This study investigated the erosion process of tile-back type slope with non-uniform slopes using a 3D photo-reconstruction method during eight successive simulated rainfall events. The results showed that EG erosion began with a chain of intermittent headcuts. When the accumulated rainfall reached 76 mm, serious collapses dramatically increased the amount of sediment by 216% after the first rainfall (cumulative rainfall was about 15 mm). We quantified the sediment contribution of EG erosion (46.20%), rill erosion (35.62%), and inter-rill erosion (18.18%) to total soil loss. The erosion area of the steep slope section and extremely steep slope section accounted for 33.26% and 66.74% of the total erosion area, respectively. Moreover, sediment amounts significantly correlated with morphological parameters, particularly the amount of EG erosion and maximum gully depth, with a correlation coefficient of 0.98. Cumulative gully length and erosion area had the greatest effect on rill erosion, with a correlation coefficient of 0.97. These results provide insight into the qualitative and quantitative understanding of EG erosion process on Loess Plateau of China and an important reference for the rational arrangement of EG control measures.


Asunto(s)
Imagenología Tridimensional , Suelo , China
7.
Mol Cell ; 56(1): 104-15, 2014 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-25263593

RESUMEN

MicroRNAs (miRNAs) regulate target mRNAs through a combination of translational repression and mRNA destabilization, with mRNA destabilization dominating at steady state in the few contexts examined globally. Here, we extend the global steady-state measurements to additional mammalian contexts and find that regardless of the miRNA, cell type, growth condition, or translational state, mRNA destabilization explains most (66%->90%) miRNA-mediated repression. We also determine the relative dynamics of translational repression and mRNA destabilization for endogenous mRNAs as a miRNA is induced. Although translational repression occurs rapidly, its effect is relatively weak, such that by the time consequential repression ensues, the effect of mRNA destabilization dominates. These results imply that consequential miRNA-mediated repression is largely irreversible and provide other insights into the nature of miRNA-mediated regulation. They also simplify future studies, dramatically extending the known contexts and time points for which monitoring mRNA changes captures most of the direct miRNA effects.


Asunto(s)
Regulación de la Expresión Génica , MicroARNs/fisiología , Modelos Genéticos , Estabilidad del ARN , ARN Mensajero/metabolismo , MicroARNs/genética , MicroARNs/metabolismo
8.
PLoS Genet ; 15(4): e1008077, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30969964

RESUMEN

The role of ribosomal protein S6 (rpS6) phosphorylation in mRNA translation remains poorly understood. Here, we reveal a potential role in modulating the translation rate of chemokine (C-X-C motif) ligand 8 (CXCL8 or Interleukin 8, IL8). We observed that more CXCL8 protein was being secreted from less CXCL8 mRNA in primary macrophages and macrophage-like HL-60 cells relative to other cell types. This correlated with an increase in CXCL8 polyribosome association, suggesting an increase in the rate of CXCL8 translation in macrophages. The cell type-specific expression levels were replicated by a CXCL8- UTR-reporter (Nanoluc reporter flanked by the 5' and 3' UTR of CXCL8). Mutations of the CXCL8-UTR-reporter revealed that cell type-specific expression required: 1) a 3' UTR of at least three hundred bases; and 2) an AU base content that exceeds fifty percent in the first hundred bases of the 3' UTR immediately after the stop codon, which we dub AU-rich proximal UTR sequences (APS). The 5' UTR of CXCL8 enhanced expression at the protein level and conferred cell type-specific expression when paired with a 3' UTR. A search for other APS-positive mRNAs uncovered TNF alpha induced protein 6 (TNFAIP6), another mRNA that was translationally upregulated in macrophages. The elevated translation of APS-positive mRNAs in macrophages coincided with elevated rpS6 S235/236 phosphorylation. Both were attenuated by the ERK1/2 signaling inhibitors, U0126 and AZD6244. In A549 cells, rpS6 S235/236 phosphorylation was induced by TAK1, Akt or PKA signaling. This enhanced the translation of the CXCL8-UTR-reporters. Thus, we propose that the induction of rpS6 S235/236 phosphorylation enhances the translation of mRNAs that contain APS motifs, such as CXCL8 and TNFAIP6. This may contribute to the role of macrophages as the primary producer of CXCL8, a cytokine that is essential for immune cell recruitment and activation.


Asunto(s)
Interleucina-8/biosíntesis , Interleucina-8/genética , Proteína S6 Ribosómica/metabolismo , Células A549 , Elementos Ricos en Adenilato y Uridilato , Secuencia de Bases , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Células Cultivadas , Factor 4E Eucariótico de Iniciación/metabolismo , Células HL-60 , Humanos , Sistema de Señalización de MAP Quinasas , Macrófagos/inmunología , Macrófagos/metabolismo , Modelos Biológicos , Mutagénesis , Fosforilación , Polirribosomas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteína S6 Ribosómica/química , Proteína S6 Ribosómica/genética , Regiones no Traducidas
9.
Scand J Gastroenterol ; 55(9): 1035-1040, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32819192

RESUMEN

BACKGROUND AND AIMS: Serum infliximab trough level(S-IFX) and antibody were documented to correlate with clinical response. The aim of this study was to identify the relationship between early S-IFX, early mucosal healing (MH) and one-year outcome in a cohort on maintenance IFX therapy in Crohn's disease (CD). METHODS: The study group comprised of retrospectively enrolled patients diagnosed for Crohn's disease (n = 108). Patients received scheduled maintenance therapy after response to IFX induction, and had undergone the early S-IFX test and endoscopic examination at week 14. Clinical outcomes were evaluated during maintenance therapy until week 52. RESULTS: Early S-IFX was 4.78 ± 6.16 ug/ml in all the patients and 19% (21/108) of them developed antibodies, and 52 patients reached early MH. During 52 weeks' follow-up. Twenty-eight percent (30/108) of patients showed loss of response to IFX. Patients who lost response had lower early S-IFX than those who had sustained response (3.01 ± 3.66 vs. 5.47 ± 6.79 ug/ml, p = .02; 48 vs. 23%, p = .02). At week 52, 73 patients had repeated endoscopy and 42% of them reached MH. Early S-IFX had a predictive value on MH at week 52. When early S-IFX > 2.5 ug/ml, the sensitivity for predicting MH at week 52 was 87%, and the specificity were 61% (AUC = 0.73, p < .01). The combined predictive value of early S-IFX and early MH became stronger. Only 6% (1/18) of those patients who had low early S-IFX and had not reached early MH could reach MH at week 52. CONCLUSIONS: Early S-IFX and early MH could predict one-year response after initiating IFX therapy in Crohn's disease.


Asunto(s)
Enfermedad de Crohn , Enfermedad de Crohn/tratamiento farmacológico , Fármacos Gastrointestinales/uso terapéutico , Humanos , Infliximab/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento
10.
Inorg Chem ; 59(16): 11213-11217, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32706960

RESUMEN

The largest antimonomolybdate monomer, [Sb8MoVI13MoV5O66]5- (1-Sb8Mo18), has been isolated and displays a new breakthrough of polyoxometalates (POMs) with an ionothermal synthesis strategy. 1-Sb8Mo18 features the first hexanuclear sandwich-type polymolybdate (POMo) with an unexpected metal ring {Sb6O12} to make its debut in Sb clusters. Furthermore, 1-Sb8Mo18 exhibits a prominent catalytic activity for reducing nitrobenzene to aniline with excellent sustainability.

11.
Inorg Chem ; 59(22): 16430-16440, 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-33099996

RESUMEN

Four novel three-dimensional interpenetrating frameworks based on {P4Mo6} units, H[C12H14N2]4[TM4(PO4)(H2O)4Na6][TM2(Mo6O12(HPO4)3(PO4)(OH)3)4]·8H2O (1, 2) and H[C14H18N2]4[TM4(PO4)(H2O)4Na6][TM2(Mo6O12(HPO4)3(PO4)(OH)3)4]·8H2O (3, 4) (TM = Co2+ (1, 3), Mn2+ (2, 4)) were synthesized and characterized using infrared spectroscopy, elemental analyses, thermogravimetric analysis, and single-crystal X-ray diffraction. In situ generated methyl viologen (compounds 1 and 2) or ethyl viologen (compounds 3 and 4) cations function as templates to induce the generation of 2-fold interpenetrating structures in which the {P4Mo6} tetrameric clusters with [TM4(PO4)Na6] (TM = Co2+ (1, 3) and Mn2+ (2, 4)) as the core were bridged by transition metal ions. Compounds 1-4 possess high thermal stabilities and the decomposition temperature of the inorganic frameworks were all >500 °C. It is worth noting that the four compounds all exhibited the bifunctional catalytic performance that they not only had an excellent photocatalytic activity for the reduction of hexavalent chromium (Cr(VI)) under visible light irradiation but also showed a good electrocatalytic activity for the reduction reaction of hydrogen peroxide.

12.
Q J Nucl Med Mol Imaging ; 63(2): 199-206, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27327630

RESUMEN

BACKGROUND: Management of osteochondral lesions of talus (OLT) remains controversial. 99Tc-MDP, a decay product of 99mTc-MDP which is widely used for bone scan, is effective in the clinical treatment of rheumatoid arthritis. The purpose of the study is to investigate the effects of 99Tc-MDP treatment on OLT. METHODS: In the clinical evaluation, 66 patients with a total of 83 lesions of OLT who failed appropriate non-operative treatment and surgery were retrospectively included and treated with intravenous injection of 99Tc-MDP and Chinese herbal fumigation (CHF). The effects of 99Tc-MDP and CHF on OLT were evaluated by the American Orthopedic Foot and Ankle Society Ankle-Hindfoot Score (AOFAS), Visual Analog Scale (VAS), activities of daily living (Barthel Index), and MRI, 99mTc-MDP SPECT/CT and CT. Radiographic changes were also assessed by the transverse long diameter of the cyst on CT. RESULTS: At the last follow-up, AOFAS, VAS and Barthel Index improved significantly from 68.66±9.76, 3.05±0.34 and 85±8.31 to 85.4±8.31, 1.85±0.36 and 94.7±4.99 (P<0.01), respectively after one course treatment in 66 patients with OLT. Thirty one (31/66) patients had a second treatment course. Their AOFAS, VAS and Barthel Index also improved significantly after the mean follow-up of 7±2 (6-15) months. And the average diameter of the cysts decreased from 8.01±3.35 mm to 4.74±2.83 mm (P<0.01) in the 31 patients. CONCLUSIONS: The retrospective study indicates that a combination treatment of 99Tc-MDP and CHF is effective in pain relief and return of function in a short term of follow-up for patients with OLT. Our results suggest that the small cystic lesions with increased uptake of 99mTc-MDP on SPECT/CT can be well treated by 99Tc-MDP and CHF. This novel technique holds the potential to emerge as an effective conservative treatment for OLT without adverse effects. The level of evidence for 99Tc-MDP is medium for the number of patients and retrospective study.


Asunto(s)
Enfermedades Óseas/diagnóstico por imagen , Enfermedades Óseas/radioterapia , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Medronato de Tecnecio Tc 99m/uso terapéutico , Adulto , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
13.
Biochem Soc Trans ; 46(4): 855-869, 2018 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-29986937

RESUMEN

The control of translation is increasingly recognized as a major factor in determining protein levels in the cell. The ribosome - the cellular machine that mediates protein synthesis - is typically seen as a key, but invariant, player in this process. This is because translational control is thought to be mediated by other auxiliary factors while ribosome recruitment is seen as the end-point of regulation. However, recent developments have made it clear that heterogeneous ribosome types can exist in different tissues, and more importantly, that these ribosomes can preferentially translate different subsets of mRNAs. In so doing, heterogeneous ribosomes could be key regulatory players in differentiation and development. Here, we examine current evidence for the existence of different ribosome types and how they might arise. In particular, we will take a close look at the mechanisms through which these ribosomes might mediate selective mRNA translation. We also summarize recently developed techniques/approaches that will aid in our understanding of the functions of such specialized ribosomes.


Asunto(s)
Biosíntesis de Proteínas/fisiología , Proteínas/fisiología , Ribosomas/fisiología , Humanos , ARN Mensajero/metabolismo , ARN Ribosómico/metabolismo , Proteínas Ribosómicas/metabolismo
14.
BMC Health Serv Res ; 18(1): 452, 2018 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-29903011

RESUMEN

BACKGROUND: Many hospitals in China experience large volumes of emergency department (ED) radiology patients, thereby lengthening the wait times for non-emergency radiology patients. We examine whether an emergency reservation policy which deals with stochastic arrivals of ED patients can shorten wait times, and what effect it has on patient and hospital related metrics. METHODS: In this study, operations research models are used to develop an emergency reservation policy. First, we construct a discrete event simulation (DES) model based on the process of patients served by one computed tomography (CT) scanner at West China Hospital (WCH). Next, a newsvendor model is built to compute the daily reservation quantity for emergency patients. Based on the appointment scheduling rule and daily emergency reservation policies, the effects of the proposed policy on daily examination quantity, patient wait times, and equipment utilization are explicitly modeled. Finally, we evaluate the impact of different reservation policies on these system performance measures. RESULTS: Our analysis indicates that reserving capacity for emergency patients greatly shortens the delay for non-emergency patients with an average 43.9% reduction in total wait times. The pre-model utilization and average post-model utilization are 99.3% and 98.5%, respectively. In addition, the comparison of different reservation policies shows that there is no significant difference between any two policies in terms of patients' wait times. CONCLUSIONS: Reserving proper capacity for emergency patients not only positively affects the patients' delay times, but also affects various aspects of the hospital. Our goal is to design a simple and implementable emergency reservation policy. DES proves to be an effective tool for studying the effects of proposed scenarios to optimize capacity allocation in radiology management.


Asunto(s)
Servicio de Urgencia en Hospital/organización & administración , Investigación Operativa , Servicio de Radiología en Hospital/organización & administración , Citas y Horarios , China , Simulación por Computador , Humanos , Modelos Organizacionales
16.
Nature ; 466(7308): 835-40, 2010 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-20703300

RESUMEN

MicroRNAs (miRNAs) are endogenous approximately 22-nucleotide RNAs that mediate important gene-regulatory events by pairing to the mRNAs of protein-coding genes to direct their repression. Repression of these regulatory targets leads to decreased translational efficiency and/or decreased mRNA levels, but the relative contributions of these two outcomes have been largely unknown, particularly for endogenous targets expressed at low-to-moderate levels. Here, we use ribosome profiling to measure the overall effects on protein production and compare these to simultaneously measured effects on mRNA levels. For both ectopic and endogenous miRNA regulatory interactions, lowered mRNA levels account for most (>/=84%) of the decreased protein production. These results show that changes in mRNA levels closely reflect the impact of miRNAs on gene expression and indicate that destabilization of target mRNAs is the predominant reason for reduced protein output.


Asunto(s)
Regulación hacia Abajo/genética , MicroARNs/genética , MicroARNs/metabolismo , Estabilidad del ARN/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Regiones no Traducidas 3'/genética , Animales , Células HeLa , Humanos , Mamíferos/genética , Ratones , Modelos Genéticos , Sistemas de Lectura Abierta/genética , Biosíntesis de Proteínas/genética , Procesamiento Postranscripcional del ARN/genética , ARN Mensajero/análisis , Ribosomas/genética , Ribosomas/metabolismo
17.
Nature ; 453(7196): 803-6, 2008 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-18463630

RESUMEN

In contrast to microRNAs and Piwi-associated RNAs, short interfering RNAs (siRNAs) are seemingly dispensable for host-directed gene regulation in Drosophila. This notion is based on the fact that mutants lacking the core siRNA-generating enzyme Dicer-2 or the predominant siRNA effector Argonaute 2 are viable, fertile and of relatively normal morphology. Moreover, endogenous Drosophila siRNAs have not yet been identified. Here we report that siRNAs derived from long hairpin RNA genes (hpRNAs) programme Slicer complexes that can repress endogenous target transcripts. The Drosophila hpRNA pathway is a hybrid mechanism that combines canonical RNA interference factors (Dicer-2, Hen1 (known as CG12367) and Argonaute 2) with a canonical microRNA factor (Loquacious) to generate approximately 21-nucleotide siRNAs. These novel regulatory RNAs reveal unexpected complexity in the sorting of small RNAs, and open a window onto the biological usage of endogenous RNA interference in Drosophila.


Asunto(s)
Drosophila melanogaster/genética , Conformación de Ácido Nucleico , Interferencia de ARN , ARN Bicatenario/metabolismo , ARN Interferente Pequeño/metabolismo , Animales , Proteínas Argonautas , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimología , Drosophila melanogaster/metabolismo , Metiltransferasas/metabolismo , MicroARNs/biosíntesis , MicroARNs/genética , MicroARNs/metabolismo , ARN Helicasas/genética , ARN Helicasas/metabolismo , ARN Bicatenario/química , ARN Bicatenario/genética , ARN Interferente Pequeño/biosíntesis , ARN Interferente Pequeño/genética , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Complejo Silenciador Inducido por ARN/genética , Complejo Silenciador Inducido por ARN/metabolismo , Ribonucleasa III
18.
Gastroenterol Rep (Oxf) ; 12: goae003, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38344170

RESUMEN

Background: Small bowel involvement is related to poor prognosis in Crohn's disease (CD), which may be a potential marker to stratify patients with a high risk of progression. This study aimed to establish a novel location classification system for CD and to develop a predictive model for disease progression. Methods: Consecutive patients with non-stricturing/non-penetrating CD were retrospectively included in the Sixth Affiliated Hospital, Sun Yat-sen University (Guangzhou, P. R. China) between January 2012 and January 2018. Patients were classified into two groups according to disease location: small bowel involvement group and isolated colon group. The primary outcome was disease progression to stricturing or penetrating phenotypes. Progression-free survival was estimated using Cox proportional hazards regression analysis and Kaplan-Meier method. Results: A total of 463 patients were analysed, with a median follow-up time of 55.3 months. Patients with small bowel involvement had a higher risk of disease progression than those with isolated colon disease (hazard ratio = 1.998, P = 0.007), while no differences were found between Montreal location classification and disease progression. Median progression-free survival was higher in the isolated colon group than in the small bowel involvement group (84.5 vs 77.3 months, P = 0.006). Four independent factors associated with disease progression were identified: small bowel involvement, duration of onset of >1 year, deep mucosal ulcer, and C-reactive protein levels of ≥10 mg/L (all P < 0.05). The nomogram model based on these factors showed good performance in predicting disease progression, with a C-index of 0.746 (95% confidence interval, 0.707-0.785). Conclusions: Classifying CD based on small bowel involvement and isolated colon was superior to the Montreal location classification for predicting disease progression.

19.
Sleep Med ; 114: 167-177, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38211375

RESUMEN

STUDY OBJECTIVES: Coronavirus disease 2019 (COVID-19) can lead to insomnia. However, associations between COVID-19-caused insomnia and white matter (WM) changes are unclear. METHODS: All subjects had ever been infected with COVID-19. We investigated 89 insomniacs (29 chronic insomniacs, 33 new-onset insomniacs, 27 aggravated insomniacs) and 44 matched non-insomnia participants. Neurite orientation dispersion and density imaging (NODDI) was performed to identify micro-structural alterations of WM, and twelve scales related to sleeping status, memory, attention, learning, emotional status, and executive functions were used. Then, correlations between insomnia/cognitive-behavioral functions and diffusion metrics were tested. To eliminate influence of pre-COVID-19 factors on insomnia, causal relationships between COVID-19 and WM changes were validated by Mendelian randomization (MR) analysis. The significant brain regions of COVID-19-caused insomnia were intersected results of tract-based spatial statistics (TBSS) and MR analyses. RESULTS: Compared to non-insomnia group, insomnia group and its subgroups including post-COVID-19 aggravated or unchanged chronic insomnia group had higher orientation dispersion index (ODI) in extensive brain regions. The left superior longitudinal fasciculus (SLF), left posterior thalamic radiation (PTR), and left cingulate gyrus (CG) were specific brain regions in COVID-19-induced insomnia aggravation. After Bonferroni correction, partial correlation analyses within insomnia group showed that ODI in left SLF was positively correlated with Pittsburgh sleep quality index (PSQI), insomnia severity index (ISI), and self-rating anxiety scale (SAS) scores; ODI in the left PTR was positively correlated with PSQI and ISI scores. CONCLUSIONS: This study is a continuation of our previous research, which provided potential biomarkers for COVID-19-induced insomnia.


Asunto(s)
COVID-19 , Trastornos del Inicio y del Mantenimiento del Sueño , Sustancia Blanca , Humanos , Sustancia Blanca/diagnóstico por imagen , Trastornos del Inicio y del Mantenimiento del Sueño/diagnóstico por imagen , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Pandemias , Análisis de la Aleatorización Mendeliana , Imagen de Difusión Tensora/métodos , Encéfalo/diagnóstico por imagen , Neuroimagen
20.
J Affect Disord ; 351: 449-457, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38296060

RESUMEN

BACKGROUND: Insomnia is very common in psychiatric disorders, but the polysomnographic (PSG) characteristics of insomnia in various psychiatric disorders are still not agreed upon. This study aimed to investigate the characteristics of PSG and its relationship with metabolic indicators in insomnia patients with affective disorders and primary insomnia (PI) patients. METHODS: A total of 38 patients with PI, 44 major depressive disorder patients with insomnia (DI), 49 generalized anxiety disorder patients with insomnia (GI), and 19 bipolar mania patients with insomnia (BI) were included. PSG was used to detect sleep problems in subjects, and biochemical indicators were also collected. RESULTS: The results of this study found that subjects with BI were lower on REM sleep latency (RL), awakenings number (AN), number of microarousals (NM), and apnea-hypopnea index (AHI) than those with DI and GI, and lower on RL and AN than those with PI. Subjects with PI had lower NM and AHI than those with DI and GI. Patients with DI had a higher RL than those with GI. All results passed Bonferroni correction (p < 0.00078). No differences in biochemical indices were found among the four groups of subjects. Also, AHI was found to be positively correlated with free triiodothyronine (FT3) and fasting blood glucose in subjects. CONCLUSION: This study suggests that various psychiatric disorders may have their characteristics in terms of PSG parameters, which prompted us to focus on the PSG characteristics of these disorders when assessing them, as well as to focus on their biochemical indicators.


Asunto(s)
Trastorno Bipolar , Trastorno Depresivo Mayor , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Trastorno Depresivo Mayor/complicaciones , Trastorno Depresivo Mayor/diagnóstico , Trastorno Bipolar/complicaciones , Manía , Polisomnografía , Trastornos de Ansiedad/complicaciones , Trastornos de Ansiedad/diagnóstico
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