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1.
Cell ; 179(5): 1160-1176.e24, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31730855

RESUMO

Pediatric-onset colitis and inflammatory bowel disease (IBD) have significant effects on the growth of infants and children, but the etiopathogenesis underlying disease subtypes remains incompletely understood. Here, we report single-cell clustering, immune phenotyping, and risk gene analysis for children with undifferentiated colitis, Crohn's disease, and ulcerative colitis. We demonstrate disease-specific characteristics, as well as common pathogenesis marked by impaired cyclic AMP (cAMP)-response signaling. Specifically, infiltration of PDE4B- and TNF-expressing macrophages, decreased abundance of CD39-expressing intraepithelial T cells, and platelet aggregation and release of 5-hydroxytryptamine at the colonic mucosae were common in colitis and IBD patients. Targeting these pathways by using the phosphodiesterase inhibitor dipyridamole restored immune homeostasis and improved colitis symptoms in a pilot study. In summary, comprehensive analysis of the colonic mucosae has uncovered common pathogenesis and therapeutic targets for children with colitis and IBD.


Assuntos
Doenças Inflamatórias Intestinais/patologia , Doenças Inflamatórias Intestinais/terapia , Mucosa Intestinal/patologia , Antígenos CD/metabolismo , Apirase/metabolismo , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Morte Celular/efeitos dos fármacos , Microambiente Celular/efeitos dos fármacos , Criança , Estudos de Coortes , Colo/patologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Dipiridamol/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Predisposição Genética para Doença , Homeostase/efeitos dos fármacos , Humanos , Imunoglobulina G/sangue , Memória Imunológica , Inflamação/patologia , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/genética , Interferon Tipo I/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Metilprednisolona/farmacologia , Células Mieloides/efeitos dos fármacos , Células Mieloides/metabolismo
2.
Mol Cell ; 83(2): 281-297.e10, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36586411

RESUMO

As a key component of the inflammasome, NLRP3 is a critical intracellular danger sensor emerging as an important clinical target in inflammatory diseases. However, little is known about the mechanisms that determine the kinetics of NLRP3 inflammasome stability and activity to ensure effective and controllable inflammatory responses. Here, we show that S-palmitoylation acts as a brake to turn NLRP3 inflammasome off. zDHHC12 is identified as the S-acyltransferase for NLRP3 palmitoylation, which promotes its degradation through the chaperone-mediated autophagy pathway. Zdhhc12 deficiency in mice enhances inflammatory symptoms and lethality following alum-induced peritonitis and LPS-induced endotoxic shock. Notably, several disease-associated mutations in NLRP3 are associated with defective palmitoylation, resulting in overt NLRP3 inflammasome activation. Thus, our findings identify zDHHC12 as a repressor of NLRP3 inflammasome activation and uncover a previously unknown regulatory mechanism by which the inflammasome pathway is tightly controlled by the dynamic palmitoylation of NLRP3.


Assuntos
Autofagia Mediada por Chaperonas , Inflamassomos , Animais , Camundongos , Aciltransferases , Autofagia , Inflamassomos/metabolismo , Inflamação/induzido quimicamente , Inflamação/genética , Lipoilação , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
3.
Immunity ; 51(6): 983-996.e6, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31836429

RESUMO

Excessive activation of the coagulation system leads to life-threatening disseminated intravascular coagulation (DIC). Here, we examined the mechanisms underlying the activation of coagulation by lipopolysaccharide (LPS), the major cell-wall component of Gram-negative bacteria. We found that caspase-11, a cytosolic LPS receptor, activated the coagulation cascade. Caspase-11 enhanced the activation of tissue factor (TF), an initiator of coagulation, through triggering the formation of gasdermin D (GSDMD) pores and subsequent phosphatidylserine exposure, in a manner independent of cell death. GSDMD pores mediated calcium influx, which induced phosphatidylserine exposure through transmembrane protein 16F, a calcium-dependent phospholipid scramblase. Deletion of Casp11, ablation of Gsdmd, or neutralization of phosphatidylserine or TF prevented LPS-induced DIC. In septic patients, plasma concentrations of interleukin (IL)-1α and IL-1ß, biomarkers of GSDMD activation, correlated with phosphatidylserine exposure in peripheral leukocytes and DIC scores. Our findings mechanistically link immune recognition of LPS to coagulation, with implications for the treatment of DIC.


Assuntos
Caspases Iniciadoras/metabolismo , Coagulação Intravascular Disseminada/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipopolissacarídeos/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Fosfatidilserinas/metabolismo , Tromboplastina/metabolismo , Animais , Coagulação Sanguínea/fisiologia , Caspases Iniciadoras/genética , Linhagem Celular Tumoral , Endotoxemia/patologia , Ativação Enzimática , Células HT29 , Células HeLa , Humanos , Interleucina-1alfa/sangue , Interleucina-1beta/sangue , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Ligação a Fosfato/genética , Piroptose/fisiologia , Transdução de Sinais/fisiologia
4.
Trends Biochem Sci ; 48(11): 923-926, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37657995

RESUMO

Thermosensors have been identified in plants in recent years. Understanding how plants sense and respond to rising temperatures is of utmost importance currently in terms of global warming and its actual and potential impact on us. This forum explores the recent understanding of plant thermosensing and thermal responses.

5.
J Am Chem Soc ; 146(25): 17355-17364, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38870542

RESUMO

GeSe, an analogue of SnSe, shows promise in exhibiting exceptional thermoelectric performance in the Pnma phase. The constraints on its dopability, however, pose challenges in attaining optimal carrier concentrations and improving ZT values. This study demonstrates a crystal structure evolution strategy for achieving highly doped samples and promising ZTs in GeSe via LiBiTe2 alloying. A rhombohedral phase (R3m) can be stabilized in the GeSe-LiBiTe2 system, further evolving into a cubic (Fm3̅m) phase with a rising temperature. The band structures of GeSe-LiBiTe2 in the rhombohedral and cubic phases feature a similar multiple-valley energy-converged valence band of L and Σ bands. The observed high carrier concentration (∼1020 cm-3) reflects the effective convergence of these bands, enabling a high density-of-states effective mass and an enhanced power factor. Moreover, a very low lattice thermal conductivity of 0.6-0.5 W m-1 K-1 from 300 to 723 K is achieved in 0.9GeSe-0.1LiBiTe2, approaching the amorphous limit value. This remarkably low lattice thermal conductivity is related to phonon scattering from point defects, planar vacancies, and ferroelectric instability-induced low-energy Einstein oscillators. Finally, a maximum ZT value of 1.1 to 1.3 at 723 K is obtained, with a high average ZT value of over 0.8 (400-723 K) in 0.9GeSe-0.1LiBiTe2 samples. This study establishes a viable route for tailoring crystal structures to significantly improve the performance of GeSe-related compounds.

6.
J Am Chem Soc ; 146(18): 12620-12635, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38669614

RESUMO

High-entropy semiconductors are now an important class of materials widely investigated for thermoelectric applications. Understanding the impact of chemical and structural heterogeneity on transport properties in these compositionally complex systems is essential for thermoelectric design. In this work, we uncover the polar domain structures in the high-entropy PbGeSnSe1.5Te1.5 system and assess their impact on thermoelectric properties. We found that polar domains induced by crystal symmetry breaking give rise to well-structured alternating strain fields. These fields effectively disrupt phonon propagation and suppress the thermal conductivity. We demonstrate that the polar domain structures can be modulated by tuning crystal symmetry through entropy engineering in PbGeSnAgxSbxSe1.5+xTe1.5+x. Incremental increases in the entropy enhance the crystal symmetry of the system, which suppresses domain formation and loses its efficacy in suppressing phonon propagation. As a result, the room-temperature lattice thermal conductivity increases from κL = 0.63 Wm-1 K-1 (x = 0) to 0.79 Wm-1 K-1 (x = 0.10). In the meantime, the increase in crystal symmetry, however, leads to enhanced valley degeneracy and improves the weighted mobility from µw = 29.6 cm2 V-1 s-1 (x = 0) to 35.8 cm2 V-1 s-1 (x = 0.10). As such, optimal thermoelectric performance can be achieved through entropy engineering by balancing weighted mobility and lattice thermal conductivity. This work, for the first time, studies the impact of polar domain structures on thermoelectric properties, and the developed understanding of the intricate interplay between crystal symmetry, polar domains, and transport properties, along with the impact of entropy control, provides valuable insights into designing GeTe-based high-entropy thermoelectrics.

7.
Lab Invest ; 104(2): 100268, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37898292

RESUMO

Skin aging is characterized by wrinkle formation and increased frailty and laxity, leading to the risk of age-related skin diseases. Keratinocyte is an important component of the epidermis in skin structure, and keratinocyte senescence has been identified as a pivotal factor in skin aging development. Because epigenetic pathways play a vital role in the regulation of skin aging, we evaluated human skin samples for DNA hydroxymethylation (5-hydroxymethylcytosine; 5-hmC) and SIRT4 expressions. Results found that both 5-hmC and SIRT4 showed a significant decrease in aged human skin samples. To test the results in vitro, human keratinocytes were cultured in H2O2, which modulates skin aging in vivo. However, H2O2-induced keratinocytes showed senescence-associated protein expression and significant downregulation of 5-hmC and SIRT4 expressions. Moreover, 5-hmC-converting enzymes ten eleven translocation 2 (TET2) showed a decrease and enhanced TET2 acetylation level in H2O2-induced keratinocytes. However, the overexpression of SIRT4 in keratinocytes alleviates the senescence phenotype, such as senescence-associated protein expression, decreases the TET2 acetylation, but increases TET2 and 5-hmC expressions. Our results provide a novel relevant mechanism whereby the epigenetic regulation of keratinocytes in skin aging may be correlated with SIRT4 expression and TET2 acetylation in 5-hmC alteration. Our study may provide a potential strategy for antiskin aging, which targets the SIRT4/TET2 axis involving epigenetic modification in keratinocyte senescence.


Assuntos
5-Metilcitosina/análogos & derivados , Dioxigenases , Sirtuínas , Humanos , Idoso , Epigênese Genética , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Queratinócitos/metabolismo , Metilação de DNA , Proteínas Mitocondriais/genética , Sirtuínas/genética , Sirtuínas/metabolismo , Dioxigenases/metabolismo
8.
Eur Radiol ; 34(4): 2759-2771, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37736802

RESUMO

OBJECTIVES: A decline in language function is a common complication after glioma surgery, affecting patients' quality of life and survival. This study predicts the postoperative decline in language function and whether it can be recovered based on the preoperative white matter structural network. MATERIALS AND METHODS: Eighty-one right-handed patients with glioma involving the left hemisphere were retrospectively included. Their language function was assessed using the Western Aphasia Battery before and 1 week and 3 months after surgery. Structural connectome combining DTI features was selected to predict postoperative language decline and recovery. Nested cross-validation was used to optimize the models, evaluate the prediction performance of the models, and identify the most predictive features. RESULTS: Five, seven, and seven features were finally selected as the predictive features in each model and used to establish predictive models for postoperative language decline (1 week after surgery), long-term language decline (3 months after surgery), and language recovery, respectively. The overall accuracy of the three models in nested cross-validation and overall area under the receiver operating characteristic curve were 0.840, 0.790, and 0.867, and 0.841, 0.778, and 0.901, respectively. CONCLUSION: We used machine learning algorithms to establish models to predict whether the language function of glioma patients will decline after surgery and whether postoperative language deficit can recover, which may help improve the development of treatment strategies. The difference in features in the non-language decline or the language recovery group may reflect the structural basis for the protection and compensation of language function in gliomas. CLINICAL RELEVANCE STATEMENT: Models can predict the postoperative language decline and whether it can recover in glioma patients, possibly improving the development of treatment strategies. The difference in selected features may reflect the structural basis for the protection and compensation of language function. KEY POINTS: • Structural connectome combining diffusion tensor imaging features predicted glioma patients' language decline after surgery. • Structural connectome combining diffusion tensor imaging features predicted language recovery of glioma patients with postoperative language disorder. • Diffusion tensor imaging and connectome features related to language function changes imply plastic brain regions and connections.


Assuntos
Neoplasias Encefálicas , Conectoma , Glioma , Humanos , Imagem de Tensor de Difusão/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Estudos Retrospectivos , Qualidade de Vida , Glioma/diagnóstico por imagem , Glioma/cirurgia
9.
Pak J Med Sci ; 40(1Part-I): 159-164, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38196488

RESUMO

Objective: To explore the prognostic value and correlation between the risk of lymph node metastasis (LNM) and Guanylate-binding Protein 1 (GBP1) in breast cancer (BC) patients. Methods: In this retrospective study, the clinical data of 150 patients with BC who were surgically resected in The Affiliated Qingdao Central Hospital of Qingdao University from January 2019 to December 2021 were included. Patients were divided into metastasis group (n=110) or non-metastasis group (n=40) according to whether there was LNM post-surgery. Logistic regression was used to analyze the risk factors for LNM in BC, and Kaplan-Meier was used to assess the risk of disease progression 12 months post-operation in both groups. Patients were divided into a GBP1 low expression-group (n=75) or a GBP1 high expression-group (n=75). The risk of disease progression, one-year post-surgery was analyzed, and the predictive value of GBP1 in BC tissue was assessed by the receiver operating characteristics (ROC) curve. Results: Independent risk factors for BC with LNM were GBP1, CEA and TNM stage (P<0.05). There is a linear relationship between GBP1 expression and LNM risk in BC (χ2=0.88, P<0.05). Patients with high expression of GBP1 had a higher risk of LNM (χ2=3.204, P<0.001) and early postoperative progression (χ2=7.412, P<0.05). The AUC of GBP1 in predicting the risk of LNM was 0.840. Conclusions: Patients with BC and a higher expression of GBP1 could be at an increased risk of LNM. Elevations in GBP1 expression can also suggest a poor prognosis for patients with BC.

10.
J Am Chem Soc ; 145(5): 3211-3220, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36701174

RESUMO

The class I-III-VI2 diamondoid compounds with tetrahedral bonding are important semiconductors widely applied in optoelectronics. Understanding their heat transport properties and developing an effective method to predict the diamondoid solid solutions' thermal conductivity will help assess their impact as thermoelectrics. In this work, we investigated in detail the heat transport properties of CuGa1-xInxTe2 and Cu1-xAgxGaTe2 and found that in the Ag-alloyed solid solutions, the Ag atom off-centering effect results in crystallographic distortion and extra strong acoustic-optical phonon scattering and an extremely low lattice thermal conductivity. Moreover, we integrate the alloy scattering and the off-centering effect with the crystallographic distortion parameter to develop a modified Klemens model that predicts the thermal conductivity of diamondoid solid solutions. Finally, we demonstrate that Cu1-xAgxGaTe2 solid solutions are promising p-type thermoelectric materials, with a maximum ZT of 1.23 at 850 K for Cu0.58Ag0.4GaTe2.

11.
J Am Chem Soc ; 145(48): 26383-26392, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37983008

RESUMO

Covalent organic frameworks (COFs) create extended two-dimensional (2D) skeletons and aligned one-dimensional (1D) channels, constituting a class of novel π architectures with predesignable structural ordering. A distinct feature is that stacks of π building units in skeletons shape the pore walls, onto which a diversity of different units can be assembled to form various pore interfaces, opening a great potential to trigger a strong structural correlation between the skeleton and the pore. However, such a possibility has not yet been explored. Herein, we report reversible three-dimensional (3D) coalescence and interlocked actions between the skeleton and pore in COFs by controlling hydrogen-bonding networks in the pores. Introducing carboxylic acid units to the pore walls develops COFs that can confine water molecular networks, which are locked by the surface carboxylic acid units on the pore walls via multipoint, multichain, and multidirectional hydrogen-bonding interactions. As a result, the skeleton undergoes an interlocked action with pores to shrink over the x-y plane and to stack closer along the z direction upon water uptake. Remarkably, this interlocked action between the skeleton and pore is reversibly driven by water adsorption and desorption and triggers profound effects on π electronic structures and functions, including band gap, light absorption, and emission.

12.
J Am Chem Soc ; 145(29): 15997-16014, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37432784

RESUMO

The alloyed lead/tin (Pb/Sn) halide perovskites have gained significant attention in the development of tandem solar cells and other optoelectronic devices due to their widely tunable absorption edge. To gain a better understanding of the intriguing properties of Pb/Sn perovskites, such as their anomalous bandgap's dependence on stoichiometry, it is important to deepen the understanding of their chemical behavior and local structure. Herein, we investigate a series of two-dimensional Ruddlesden-Popper (RP) and Dion-Jacobson (DJ) phase alloyed Pb/Sn bromide perovskites using butylammonium (BA) and 3-(aminomethyl)pyridinium (3AMPY) as the spacer cations: (BA)2(MA)n-1PbxSnn-xBr3n+1 (n = 1-3) and (3AMPY)(MA)n-1PbxSnn-xBr3n+1 (n = 1-3) through a solution-based approach. Our results show that the ratio and site preference of Pb/Sn atoms are influenced by the layer thickness (n) and spacer cations (A'), as determined by single-crystal X-ray diffraction. Solid-state 1H, 119Sn, and 207Pb NMR spectroscopy analysis shows that the Pb atoms prefer the outer layers in n = 3 members: (BA)2(MA)PbxSnn-xBr10 and (3AMPY)(MA)PbxSnn-xBr10. Layered 2D DJ alloyed Pb/Sn bromide perovskites (3AMPY)(MA)n-1PbxSnn-xBr3n+1 (n = 1-3) demonstrate much narrower optical band gaps, lower energy PL emission peaks, and longer carrier lifetimes compared to those of RP analogs. Density functional theory calculations suggest that Pb-rich alloys (Pb:Sn ∼4:1) for n = 1 compounds are thermodynamically favored over 50:50 (Pb:Sn ∼1:1) compositions. From grazing-incidence wide-angle X-ray scattering (GIWAXS), we see that films in the RP phase orient parallel to the substrate, whereas for DJ cases, random orientations are observed relative to the substrate.

13.
J Am Chem Soc ; 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37026697

RESUMO

Entropy-engineered materials are garnering considerable attention owing to their excellent mechanical and transport properties, such as their high thermoelectric performance. However, understanding the effect of entropy on thermoelectrics remains a challenge. In this study, we used the PbGeSnCdxTe3+x family as a model system to systematically investigate the impact of entropy engineering on its crystal structure, microstructure evolution, and transport behavior. We observed that PbGeSnTe3 crystallizes in a rhombohedral structure at room temperature with complex domain structures and transforms into a high-temperature cubic structure at ∼373 K. By alloying CdTe with PbGeSnTe3, the increased configurational entropy lowers the phase-transition temperature and stabilizes PbGeSnCdxTe3+x in the cubic structure at room temperature, and the domain structures vanish accordingly. The high-entropy effect results in increased atomic disorder and consequently a low lattice thermal conductivity of 0.76 W m-1 K-1 in the material owing to enhanced phonon scattering. Notably, the increased crystal symmetry is conducive to band convergence, which results in a high-power factor of 22.4 µW cm-1 K-1. As a collective consequence of these factors, a maximum ZT of 1.63 at 875 K and an average ZT of 1.02 in the temperature range of 300-875 K were obtained for PbGeSnCd0.08Te3.08. This study highlights that the high-entropy effect can induce a complex microstructure and band structure evolution in materials, which offers a new route for the search for high-performance thermoelectrics in entropy-engineered materials.

14.
Small ; 19(17): e2207831, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36670085

RESUMO

Low conductivity over a wide temperature region due to ultra-slow ion migration dynamics is a key issue in the field of solid-state electrolytes (SSE), which needs to be solved and improved. Covalent organic frameworks (COFs), a rapidly growing class of porous crystalline materials, emerge as a new research hotspot in the field of SSEs. This is due to their homogeneously dispersed sites and well-defined pathways for ion diffusion, demonstrating great advantages over conventional non-porous solids. Herein, a composite solid electrolyte by confining organic ionic plastic crystal (OIPC) in the 1D ordered nanochannels of COFs as the host matrix for solid-state lithium-ion conduction, is reported. Due to the loss of coupling between PBu4 + cations and TFSI- anions, the cation-anion interaction is weakened; and thus, the lithium-ion transportation is facilitated. As a result, the COF-confining OIPC SSEs show ultra-high lithium-ion conductivity of 0.048 S cm-1 at 30 °C and 0.021 S cm-1 at the extremely low temperature of -30 °C. The dynamic origin of this fast ion conduction is characterized by differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy (XPS), and variable temperature solid-state nuclear magnetic resonance (NMR) spectroscopy.

15.
Small ; 19(8): e2205315, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36470676

RESUMO

In recent years, the rapid development of modern society is calling for advanced energy storage to meet the growing demands of energy supply and generation. As one of the most promising energy storage systems, secondary batteries are attracting much attention. The electrolyte is an important part of the secondary battery, and its composition is closely related to the electrochemical performance of the secondary batteries. Lithium-ion battery electrolyte is mainly composed of solvents, additives, and lithium salts, which are prepared according to specific proportions under certain conditions and according to the needs of characteristics. This review analyzes the advantages and current problems of the liquid electrolytes in lithium-ion batteries (LIBs) from the mechanism of action and failure mechanism, summarizes the research progress of solvents, lithium salts, and additives, analyzes the future trends and requirements of lithium-ion battery electrolytes, and points out the emerging opportunities in advanced lithium-ion battery electrolytes development.

16.
World J Urol ; 41(8): 2141-2148, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37318624

RESUMO

PURPOSE: The aim of our study is to describe the genetic features and correlation between the genotype and phenotype of Chinese patients with primary hyperoxaluria type 3 (PH3). METHODS: The genetic and clinical data of PH3 patients in our cohort were collected and analyzed retrospectively. All published studies of Chinese PH3 populations between January 2010 and November 2022 were searched and enrolled based on inclusive standards. RESULTS: A total of 60 Chinese PH3 patients (21 cases from our cohort and 39 cases from previous studies) were included. The mean age of onset was 1.62 ± 1.35 (range 0.4-7) years. A total of 29 different variants in the HOGA1 gene were found. The mutations were most commonly clustered in exons 1, 6, and 7. Among the genotypes, exon 6 skipping (c.834G > A and c.834_834 + 1GG > TT mutations) was the most common, followed by c.769 T > G; the allele frequencies (AFs) were 48.76% and 12.40%, respectively. Patients homozygous for exon 6 skipping exhibited a median age of onset of 0.67 (0.58-1) years, which was significantly lower than that observed among heterozygotes and nonexon 6 skipping patients (p = 0.021). A total of 22.5% (9/40) of PH3 patients had a decreased estimated glomerular filtration rate, and one patient with homozygous exon 6 skipping developed end-stage renal disease. CONCLUSIONS: A hotspot mutation, potential hotspot mutation and genotype-phenotype correlation were found in Chinese PH3 patients. This study expands the mutational spectrum and contributes to the understanding of genotypic profiles of PH3, which may provide a potential diagnostic and therapeutic target.


Assuntos
Hiperoxalúria Primária , Oxo-Ácido-Liases , Humanos , População do Leste Asiático , Genótipo , Hiperoxalúria Primária/genética , Mutação , Fenótipo , Estudos Retrospectivos , Oxo-Ácido-Liases/genética
17.
Biometrics ; 79(2): 1268-1279, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35348206

RESUMO

Missing data are frequently encountered in various disciplines and can be divided into three categories: missing completely at random (MCAR), missing at random (MAR), and missing not at random (MNAR). Valid statistical approaches to missing data depend crucially on correct identification of the underlying missingness mechanism. Although the problem of testing whether this mechanism is MCAR or MAR has been extensively studied, there has been very little research on testing MAR versus MNAR. A critical challenge that is faced when dealing with this problem is the issue of model identification under MNAR. In this paper, under a logistic model for the missing probability, we develop two score tests for the problem of whether the missingness mechanism is MAR or MNAR under a parametric model and a semiparametric location model on the regression function. The implementation of the score tests circumvents the identification issue as it requires only parameter estimation under the null MAR assumption. Our simulations and analysis of human immunodeficiency virus data show that the score tests have well-controlled type I errors and desirable powers.


Assuntos
Modelos Estatísticos , Humanos , Modelos Logísticos
18.
Biometrics ; 79(4): 3215-3226, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37221141

RESUMO

Inverse probability weighting (IPW) methods are commonly used to analyze nonignorable missing data (NIMD) under the assumption of a logistic model for the missingness probability. However, solving IPW equations numerically may involve nonconvergence problems when the sample size is moderate and the missingness probability is high. Moreover, those equations often have multiple roots, and identifying the best root is challenging. Therefore, IPW methods may have low efficiency or even produce biased results. We identify the pitfall in these methods pathologically: they involve the estimation of a moment-generating function (MGF), and such functions are notoriously unstable in general. As a remedy, we model the outcome distribution given the covariates of the completely observed individuals semiparametrically. After forming an induced logistic regression (LR) model for the missingness status of the outcome and covariate, we develop a maximum conditional likelihood method to estimate the underlying parameters. The proposed method circumvents the estimation of an MGF and hence overcomes the instability of IPW methods. Our theoretical and simulation results show that the proposed method outperforms existing competitors greatly. Two real data examples are analyzed to illustrate the advantages of our method. We conclude that if only a parametric LR is assumed but the outcome regression model is left arbitrary, then one has to be cautious in using any of the existing statistical methods in problems involving NIMD.


Assuntos
Modelos Estatísticos , Humanos , Interpretação Estatística de Dados , Probabilidade , Simulação por Computador , Modelos Logísticos
19.
Pediatr Nephrol ; 38(11): 3645-3661, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37306718

RESUMO

BACKGROUND: The aim of this study was to describe the genotypic and phenotypic characteristics of Chinese pediatric patients with hereditary nephrolithiasis. METHODS: Whole-exome sequencing (WES) was performed on 218 Chinese pediatric patients with kidney stones, and genetic and clinical data were collected and analyzed retrospectively. RESULTS: The median age at onset in our cohort was 2.5 years (age range, 0.3-13 years). We detected 79 causative mutations in 15 genes, leading to a molecular diagnosis in 38.99% (85/218) of all cases. Monogenic mutations were present in 80 cases, and digenic mutations were present in 5 cases; 34.18% (27/79) of mutations were not included in the databases. Six common mutant genes, i.e., HOGA1, AGXT, GRHPR, SLC3A1, SLC7A9, and SLC4A1, were found in 84.71% of the patients overall. Furthermore, three mutations (A278A, c.834_834 + 1GG > TT, and C257G) in HOGA1, two mutations (K12QfX156 and S275RfX28) in AGXT, and one mutation (C289DfX22) in GRHPR represented hotspot mutations. The patients with HOGA1 mutations had the earliest onset age (0.8 years), followed by those with SLC7A9 (1.8 years), SLC4A1 (2.7 years), AGXT (4.3 years), SLC3A1 (4.8 years), and GRHPR (8 years) mutations (p = 0.002). Nephrocalcinosis was most commonly observed in patients with AGXT gene mutations. CONCLUSIONS: Fifteen causative genes were detected in 85 Chinese pediatric patients with kidney stone diseases. The most common mutant genes, novel mutations, hotspot mutations, and genotype-phenotype correlations were also found. This study contributes to the understanding of genetic profiles and clinical courses in pediatric patients with hereditary nephrolithiasis. A higher resolution version of the Graphical abstract is available as Supplementary information.


Assuntos
População do Leste Asiático , Cálculos Renais , Criança , Humanos , Lactente , Pré-Escolar , Adolescente , Estudos Retrospectivos , Mutação , Cálculos Renais/diagnóstico , Cálculos Renais/genética , Genótipo
20.
J Integr Neurosci ; 22(5): 135, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37735118

RESUMO

BACKGROUND: Glioma is the most common intracranial malignancy. Immune-infiltration and tumour stemness are associated with the prognosis of glioma. Although pleckstrin homology containing family A, number 4 (PLEKHA4) is widely expressed in various human cancers, its role in glioma remains unclear. METHODS: We examined the features and clinical significance of PLEKHA4 in gliomas by analysing relevant data from the Chinese Glioma Genome Atlas (CGGA) and The Cancer Genome Atlas (TCGA) databases. Gene set enrichment analysis (GSEA) was performed to determine the possible functions and pathways involving PLEKHA4 in glioma. The relationship between PLEKHA4 expression and the degree of oncogenic dedifferentiation was analysed using stemness scores (ss) calculated from epigenetic and transcriptomic features. We also explored the relationship between PLEKHA4 expression and immune cell infiltration in gliomas using the CIBERSORT databases. Furthermore, drug sensitivity analysis was performed using datasets from the GDSC and GTRP databases. In addition, we performed relevant in vitro experimental studies. RESULTS: PLEKHA4 DNA hypomethylation status was associated with its high expression in glioma tissues as well as poor prognoses. Univariate and multivariate Cox analyses indicated that PLEKHA4 expression may be considered as an independent prognostic factor in patients with glioma. GSEA indicated that high PLEKHA4 expression was associated with Janus kinase (JAK)/signal transducer and activator of transcription (STAT), Wingless-Type MMTV Integration Site Family (Wnt), JUN N-terminal kinase (JNK) signalling pathways and involved in apoptotic, cytoskeletal, and cell adhesion biological processes (BPs). In addition, increased PLEKHA4 expression was associated with higher glioma stemness scores than lower PLEKHA4 expression levels. Furthermore, the expression of PLEKHA4 was shown to be associated with glioma infiltration by CD4+ T cells, B cells, neutrophils, macrophages, and dendritic cells. Drug sensitivity analysis also showed that PLEKHA4 expression was negatively correlated with the sensitivity of several small molecule kinase inhibitors. Furthermore, in vitro experiments confirmed that PLEKHA4 knockdown inhibited the proliferation of glioma cells. CONCLUSIONS: PLEKHA4 is highly expressed in glioma tissues and correlated with tumour stemness, immune cell infiltration and proliferation, suggesting its potential as a novel prognostic biomarker and therapeutic target in glioma.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Povo Asiático , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Proliferação de Células/genética , Glioma/genética , Glioma/imunologia , Células-Tronco Neoplásicas/imunologia , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
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