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1.
Blood ; 143(23): 2433-2437, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38518102

RESUMO

ABSTRACT: Iron-mediated induction of bone morphogenetic protein (BMP)6 expression by liver endothelial cells is essential for iron homeostasis regulation. We used multiple dietary and genetic mouse cohorts to demonstrate a minor functional role for the metal-ion transporter ZIP8 in regulating BMP6 expression under high-iron conditions.


Assuntos
Proteína Morfogenética Óssea 6 , Proteínas de Transporte de Cátions , Ferro , Animais , Proteína Morfogenética Óssea 6/metabolismo , Proteína Morfogenética Óssea 6/genética , Camundongos , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/genética , Ferro/metabolismo , Células Endoteliais/metabolismo , Camundongos Knockout , Regulação da Expressão Gênica , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Homeostase
2.
J Cell Sci ; 136(12)2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37232206

RESUMO

Mitochondrial dynamics regulate the quality and morphology of mitochondria. Calcium (Ca2+) plays an important role in regulating mitochondrial function. Here, we investigated the effects of optogenetically engineered Ca2+ signaling on mitochondrial dynamics. More specifically, customized illumination conditions could trigger unique Ca2+ oscillation waves to trigger specific signaling pathways. In this study, we found that modulating Ca2+ oscillations by increasing the light frequency, intensity and exposure time could drive mitochondria toward the fission state, mitochondrial dysfunction, autophagy and cell death. Moreover, illumination triggered phosphorylation at the Ser616 residue but not the Ser637 residue of the mitochondrial fission protein, dynamin-related protein 1 (DRP1, encoded by DNM1L), via the activation of Ca2+-dependent kinases CaMKII, ERK and CDK1. However, optogenetically engineered Ca2+ signaling did not activate calcineurin phosphatase to dephosphorylate DRP1 at Ser637. In addition, light illumination had no effect on the expression levels of the mitochondrial fusion proteins mitofusin 1 (MFN1) and 2 (MFN2). Overall, this study provides an effective and innovative approach to altering Ca2+ signaling for controlling mitochondrial fission with a more precise resolution than pharmacological approaches in the temporal dimension.


Assuntos
Cálcio , Dinâmica Mitocondrial , Dinâmica Mitocondrial/fisiologia , Cálcio/metabolismo , Dinaminas/genética , Dinaminas/metabolismo , Mitocôndrias/metabolismo , Fosforilação , Morte Celular , Proteínas Mitocondriais/metabolismo
3.
Am J Pathol ; 194(7): 1346-1373, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38631549

RESUMO

Because the mechanotransduction by stromal stiffness stimulates the rupture and repair of the nuclear envelope in pancreatic progenitor cells, accumulated genomic aberrations are under selection in the tumor microenvironment. Analysis of cell growth, micronuclei, and phosphorylated Ser-139 residue of the histone variant H2AX (γH2AX) foci linked to mechanotransduction pressure in vivo during serial orthotopic passages of mouse KrasLSL-G12D/+;Trp53flox/flox;Pdx1-Cre (KPC) cancer cells in the tumor and in migrating through the size-restricted 3-µm micropores. To search for pancreatic cancer cell-of-origin, analysis of single-cell data sets revealed that the extracellular matrix shaped an alternate route of acinar-ductal transdifferentiation of acinar cells into topoisomerase II α (TOP2A)-overexpressing cancer cells and derived subclusters with copy number amplifications in MYC-PTK2 (protein tyrosine kinase 2) locus and PIK3CA. High-PTK2 expression is associated with 171 differentially methylated CpG loci, 319 differentially expressed genes, and poor overall survival in The Cancer Genome Atlas-Pancreatic Adenocarcinoma cohort. Abolished RGD-integrin signaling by disintegrin KG blocked the PTK2 phosphorylation, increased cancer apoptosis, decreased vav guanine nucleotide exchange factor 1 (VAV1) expression, and prolonged overall survival in the KPC mice. Reduction of α-smooth muscle actin deposition in the CD248 knockout KPC mice remodeled the tissue stroma and down-regulated TOP2A expression in the epithelium. In summary, stromal stiffness induced the onset of cancer cells-of-origin by ectopic TOP2A expression, and the genomic amplification of MYC-PTK2 locus via alternative transdifferentiation of pancreatic progenitor cells is the vulnerability useful for disintegrin KG treatment.


Assuntos
Instabilidade Cromossômica , Progressão da Doença , Neoplasias Pancreáticas , Animais , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Camundongos , Humanos , Carcinoma in Situ/patologia , Carcinoma in Situ/genética , Carcinoma in Situ/metabolismo , Células Estromais/metabolismo , Células Estromais/patologia , Microambiente Tumoral , Mecanotransdução Celular , Quinase 1 de Adesão Focal
4.
Blood ; 141(4): 422-432, 2023 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-36322932

RESUMO

Transferrin receptor 1 (TfR1) performs a critical role in cellular iron uptake. Hepatocyte TfR1 is also proposed to influence systemic iron homeostasis by interacting with the hemochromatosis protein HFE to regulate hepcidin production. Here, we generated hepatocyte Tfrc knockout mice (Tfrcfl/fl;Alb-Cre+), either alone or together with Hfe knockout or ß-thalassemia, to investigate the extent to which hepatocyte TfR1 function depends on HFE, whether hepatocyte TfR1 impacts hepcidin regulation by serum iron and erythropoietic signals, and its contribution to hepcidin suppression and iron overload in ß-thalassemia. Compared with Tfrcfl/fl;Alb-Cre- controls, Tfrcfl/fl;Alb-Cre+ mice displayed reduced serum and liver iron; mildly reduced hematocrit, mean cell hemoglobin, and mean cell volume; increased erythropoietin and erythroferrone; and unchanged hepcidin levels that were inappropriately high relative to serum iron, liver iron, and erythroferrone levels. However, ablation of hepatocyte Tfrc had no impact on iron phenotype in Hfe knockout mice. Tfrcfl/fl;Alb-Cre+ mice also displayed a greater induction of hepcidin by serum iron compared with Tfrcfl/fl;Alb-Cre- controls. Finally, although acute erythropoietin injection similarly reduced hepcidin in Tfrcfl/fl;Alb-Cre+ and Tfrcfl/fl;Alb-Cre- mice, ablation of hepatocyte Tfrc in a mouse model of ß-thalassemia intermedia ameliorated hepcidin deficiency and liver iron loading. Together, our data suggest that the major nonredundant function of hepatocyte TfR1 in iron homeostasis is to interact with HFE to regulate hepcidin. This regulatory pathway is modulated by serum iron and contributes to hepcidin suppression and iron overload in murine ß-thalassemia.


Assuntos
Proteína da Hemocromatose , Ferro , Receptores da Transferrina , Talassemia beta , Animais , Camundongos , Talassemia beta/genética , Talassemia beta/metabolismo , Eritropoetina/metabolismo , Proteína da Hemocromatose/genética , Proteína da Hemocromatose/metabolismo , Hepatócitos/metabolismo , Hepcidinas/genética , Hepcidinas/metabolismo , Homeostase , Ferro/metabolismo , Sobrecarga de Ferro/genética , Sobrecarga de Ferro/metabolismo , Camundongos Knockout , Receptores da Transferrina/genética , Receptores da Transferrina/metabolismo
5.
Blood ; 142(15): 1312-1322, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37478395

RESUMO

Hepcidin is the master regulator of systemic iron homeostasis. The bone morphogenetic protein (BMP) signaling pathway is a critical regulator of hepcidin expression in response to iron and erythropoietic drive. Although endothelial-derived BMP6 and BMP2 ligands have key functional roles as endogenous hepcidin regulators, both iron and erythropoietic drives still regulate hepcidin in mice lacking either or both ligands. Here, we used mice with an inactivating Bmp5 mutation (Bmp5se), either alone or together with a global or endothelial Bmp6 knockout, to investigate the functional role of BMP5 in hepcidin and systemic iron homeostasis regulation. We showed that Bmp5se-mutant mice exhibit hepcidin deficiency at age 10 days, blunted hepcidin induction in response to oral iron gavage, and mild liver iron loading when fed on a low- or high-iron diet. Loss of 1 or 2 functional Bmp5 alleles also leads to increased iron loading in Bmp6-heterozygous mice and more profound hemochromatosis in global or endothelial Bmp6-knockout mice. Moreover, double Bmp5- and Bmp6-mutant mice fail to induce hepcidin in response to long-term dietary iron loading. Finally, erythroferrone binds directly to BMP5 and inhibits BMP5 induction of hepcidin in vitro. Although erythropoietin suppresses hepcidin in Bmp5se-mutant mice, it fails to suppress hepcidin in double Bmp5- and Bmp6-mutant males. Together, these data demonstrate that BMP5 plays a functional role in hepcidin and iron homeostasis regulation, particularly under conditions in which BMP6 is limited.


Assuntos
Hemocromatose , Hepcidinas , Animais , Masculino , Camundongos , Proteína Morfogenética Óssea 6/metabolismo , Hemocromatose/genética , Hepcidinas/genética , Hepcidinas/metabolismo , Homeostase , Ferro/metabolismo , Fígado/metabolismo , Camundongos Knockout
6.
Nano Lett ; 24(25): 7645-7653, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38875704

RESUMO

Understanding the nucleation and growth mechanism of 3d transition bimetallic nanocrystals (NCs) is crucial to developing NCs with tailored nanostructures and properties. However, it remains a significant challenge due to the complexity of 3d bimetallic NCs formation and their sensitivity to oxygen. Here, by combining in situ electron microscopy and synchrotron X-ray techniques, we elucidate the nucleation and growth pathways of Fe-Ni NCs. Interestingly, the formation of Fe-Ni NCs emerges from the assimilation of Fe into Ni clusters together with the reduction of Fe-Ni oxides. Subsequently, these NCs undergo solid-state phase transitions, resulting in two distinct solid solutions, ultimately dominated by γ-Fe3Ni2. Furthermore, we deconvolve the interplays between local coordination and electronic state concerning the growth temperature. We directly visualize the oxidation-state distributions of Fe and Ni at the nanoscale and investigate their changes. This work may reshape and enhance the understanding of nucleation and growth in atomic crystallization.

7.
Cancer ; 130(6): 985-994, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-37962072

RESUMO

BACKGROUND: Although immunotherapy has emerged as a therapeutic strategy for many cancers, there are limited studies establishing the safety and efficacy in people living with HIV (PLWH) and cancer. METHODS: PLWH and solid tumors or Kaposi sarcoma (KS) receiving antiretroviral therapy and a suppressed HIV viral load received nivolumab at 3 mg/kg every 2 weeks, in two dose deescalation cohorts stratified by CD4 count (stratum 1: CD4 count > 200/µL and stratum 2: CD4 count 100-199/µL). An expansion cohort of 24 participants with a CD4 count > 200/µL was then enrolled. RESULTS: A total of 36 PLWH received nivolumab, including 15 with KS and 21 with a variety of other solid tumors. None of the first 12 participants had dose-limiting toxicity in both CD4 strata, and five patients (14%) overall had grade 3 or higher immune related adverse events. Objective partial response occurred in nine PLWH and cancer (25%), including in six of 15 with KS (40%; 95% CI, 16.3-64.7). The median duration of response was 9.0 months overall and 12.5 months in KS. Responses were observed regardless of PDL1 expression. There were no significant changes in CD4 count or HIV viral load. CONCLUSIONS: Nivolumab has a safety profile in PLWH similar to HIV-negative subjects with cancer, and also efficacy in KS. Plasma HIV remained suppressed and CD4 counts remained stable during treatment and antiretroviral therapy, indicating no adverse impact on immune function. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02408861.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Sarcoma de Kaposi , Humanos , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Nivolumabe/efeitos adversos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Sarcoma de Kaposi/tratamento farmacológico , Contagem de Linfócito CD4 , Carga Viral
8.
Mol Genet Genomics ; 299(1): 62, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869622

RESUMO

Sodium taurocholate co-transporting polypeptide (NTCP), a bile acid transporter, plays a crucial role in regulating bile acid levels and influencing the risk of HBV infection. Genetic variations in the SLC10A1 gene, which encodes NTCP, affect these functions. However, the impact of SLC10A1 gene variants on the metabolic and biochemical traits remained unclear. We aimed to investigate the association of SLC10A1 gene variants with the clinical and biochemical parameters, and the risk of different HBV infection statuses and gallstone disease in the Taiwanese population. Genotyping data from 117,679 Taiwan Biobank participants were analyzed using the Axiom genome-wide CHB arrays. Regional-plot association analysis demonstrated genome-wide significant association between the SLC10A1 rs2296651 genotypes and lipid profile, gamma glutamyl transferase (γGT) level and anti-HBc-positivity. Genotype-phenotype association analyses revealed significantly lower total cholesterol, low-density lipoprotein (LDL) cholesterol and uric acid levels, a higher γGT level and a higher gallstone incidence in rare rs2296651-A allele carrier. Participants with the rs2296651 AA-genotype exhibited significantly lower rates of anti-HBc-positivity and HBsAg-positivity. Compared to those with the GG-genotype, individuals with non-GG-genotypes had reduced risks for various HBV infection statuses: the AA-genotype showed substantially lower risks, while the GA-genotype demonstrated modestly lower risks. Predictive tools also suggested that the rs2296651 variant potentially induced protein damage and pathogenic effects. In conclusion, our data revealed pleiotropic effects of the SLC10A1 rs2296651 genotypes on the levels of biochemical traits and the risk of HBV infection and gallstone disease. This confirms SLC10A1's versatility and implicates its genotypes in predicting both biochemical traits and disease susceptibility.


Assuntos
Cálculos Biliares , Predisposição Genética para Doença , Vírus da Hepatite B , Hepatite B , Transportadores de Ânions Orgânicos Dependentes de Sódio , Polimorfismo de Nucleotídeo Único , Simportadores , Humanos , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Cálculos Biliares/genética , Feminino , Simportadores/genética , Masculino , Hepatite B/genética , Hepatite B/virologia , Vírus da Hepatite B/patogenicidade , Pessoa de Meia-Idade , Taiwan/epidemiologia , Adulto , Genótipo , Estudo de Associação Genômica Ampla , Estudos de Associação Genética , Fatores de Risco
9.
Small ; 20(24): e2311811, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38372500

RESUMO

Amid growing interest in using body heat for electricity in wearables, creating stretchable devices poses a major challenge. Herein, a hydrogel composed of two core constituents, namely the negatively-charged 2-acrylamido-2-methylpropanesulfonic acid and the zwitterionic (ZI) sulfobetaine acrylamide, is engineered into a double-network hydrogel. This results in a significant enhancement in mechanical properties, with tensile stress and strain of up to 470.3 kPa and 106.6%, respectively. Moreover, the ZI nature of the polymer enables the fabrication of a device with polar thermoelectric properties by modulating the pH. Thus, the ionic Seebeck coefficient (Si) of the ZI hydrogel ranges from -32.6 to 31.7 mV K-1 as the pH is varied from 1 to 14, giving substantial figure of merit (ZTi) values of 3.8 and 3.6, respectively. Moreover, a prototype stretchable ionic thermoelectric supercapacitor incorporating the ZI hydrogel exhibits notable power densities of 1.8 and 0.9 mW m-2 at pH 1 and 14, respectively. Thus, the present work paves the way for the utilization of pH-sensitive, stretchable ZI hydrogels for thermoelectric applications, with a specific focus on harvesting low-grade waste heat within the temperature range of 25-40 °C.

10.
Am J Kidney Dis ; 83(1): 37-46, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37657635

RESUMO

RATIONALE & OBJECTIVE: Patients with glomerular disease (GN) may be at increased risk of severe COVID-19, yet concerns over vaccines causing disease relapse may lead to vaccine hesitancy. We examined the associations of COVID-19 with longitudinal kidney function and proteinuria and compared these with similar associations with COVID-19 vaccination. STUDY DESIGN: Observational cohort study from July 1, 2021, to January 1, 2023. SETTING & PARTICIPANTS: A prospective observational study network of 71 centers from North America and Europe (CureGN) with children and adults with primary minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, or IgA nephropathy. EXPOSURE: COVID-19 and COVID-19 vaccination. OUTCOME: Repeated measure of estimated glomerular filtration rate (eGFR); recurrent time-to-event outcome of GN disease worsening as defined by doubling of the urinary protein-creatinine ratio (UPCR) to at least 1.5g/g or increase in dipstick urine protein by 2 ordinal levels to 3+(300mg/dL) or above. ANALYTICAL APPROACH: Interrupted time series analysis for eGFR. Prognostic matched sequential stratification recurrent event analysis for GN disease worsening. RESULTS: Among 2,055 participants, 722 (35%) reported COVID-19 infection; of these, 92 (13%) were hospitalized, and 3 died (<1%). The eGFR slope before COVID-19 infection was-1.40mL/min/1.73m2 (± 0.29 SD); within 6 months after COVID-19 infection, the eGFR slope was-4.26mL/min/1.73m2 (± 3.02 SD), which was not significantly different (P=0.34). COVID-19 was associated with increased risk of worsening GN disease activity (HR, 1.35 [95% CI, 1.01-1.80]). Vaccination was not associated with a change in eGFR (-1.34mL/min/1.73m2±0.15 SD vs-2.16mL/min/1.73m2±1.74 SD; P=0.6) or subsequent GN disease worsening (HR 1.02 [95% CI, 0.79-1.33]) in this cohort. LIMITATIONS: Infrequent or short follow-up. CONCLUSIONS: Among patients with primary GN, COVID-19 infection was severe for 1 in 8 cases and was associated with subsequent worsening of GN disease activity, as defined by proteinuria. By contrast, vaccination against COVID-19 was not associated with change in disease activity or kidney function decline. These results support COVID-19 vaccination for patients with GN. PLAIN-LANGUAGE SUMMARY: In this cohort study of 2,055 patients with minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, or IgA nephropathy, COVID-19 resulted in hospitalization or death for 1 in 8 cases and was associated with a 35% increase in risk for worsening proteinuria. By contrast, vaccination did not appear to adversely affect kidney function or proteinuria. Our data support vaccination for COVID-19 in patients with glomerular disease.


Assuntos
COVID-19 , Glomerulonefrite por IGA , Glomerulonefrite Membranosa , Glomerulosclerose Segmentar e Focal , Nefrose Lipoide , Adulto , Criança , Humanos , Estudos de Coortes , COVID-19/complicações , COVID-19/epidemiologia , Vacinas contra COVID-19/efeitos adversos , Taxa de Filtração Glomerular , Glomerulonefrite por IGA/urina , Glomérulos Renais , Proteinúria/epidemiologia , Vacinação , Estudos Prospectivos
11.
Chem Res Toxicol ; 37(9): 1488-1500, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39141674

RESUMO

The susceptibility of the immune system to immunotoxic chemicals is evident, particularly in the thymus, a vital primary immune organ prone to atrophy due to exposure to toxicants. Fipronil (FPN), a widely used insecticide, is of concern due to its potential neurotoxicity, hepatotoxicity, and immunotoxicity. Our previous study showed that FPN disturbed the antigen-specific T-cell functionality in vivo. As T-cell lineage commitment and thymopoiesis are closely interconnected with the normal function of the T-cell-mediated immune responses, this study aims to further examine the toxic effects of FPN on thymocyte development. In this study, 4-week-old BALB/c mice received seven doses of FPN (1, 5, 10 mg/kg) by gavage. Thymus size, medulla/cortex ratio, total thymocyte counts, double-positive thymocyte population, and IL-7-positive cells decreased dose-dependently. IL-7 aids the differentiation of early T-cell precursors into mature T cells, and several essential genes contribute to the maturation of T cells in the thymus. Foxn1 ensures that the thymic microenvironment is suitable for the maturation of T-cell precursors. Lyl1 is involved in specifying lymphoid cells and maintaining T-cell development in the thymus. The c-Kit/SCF collaboration fosters a supportive thymic milieu to promote the formation of functional T cells. The expression of IL-7, IL-7R, c-Kit, SCF, Foxn1, and Lyl1 genes in the thymus was significantly diminished in FPN-treated groups with the concordance with the reduction of IL-7 signaling proteins (IL-7, IL-7R, c-KIT, SCF, LYL1, FOXO3A, and GABPA), suggesting that the dysregulation of T-cell lineage-related genes may contribute to the thymic atrophy induced by FPN. In addition, FPN disturbed the functionality of thymocytes with an increase of IL-4 and IFN-γ production and a decrease of IL-2 secretion after T-cell mitogen stimulation ex vivo. Collectively, FPN significantly deregulated genes related to T-cell progenitor differentiation, survival, and expansion, potentially leading to impaired thymopoiesis.


Assuntos
Atrofia , Interleucina-7 , Camundongos Endogâmicos BALB C , Pirazóis , Timócitos , Timo , Animais , Timo/efeitos dos fármacos , Timo/patologia , Interleucina-7/metabolismo , Timócitos/efeitos dos fármacos , Timócitos/patologia , Timócitos/metabolismo , Camundongos , Atrofia/induzido quimicamente , Pirazóis/farmacologia , Inseticidas/toxicidade , Relação Dose-Resposta a Droga
12.
Chem Res Toxicol ; 37(7): 1171-1186, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38870402

RESUMO

Exposure to anthropogenic aerosols has been associated with a variety of adverse health effects, increased morbidity, and premature death. Although cigarette smoke poses one of the most significant public health threats, the cellular toxicity of particulate matter contained in cigarette smoke has not been systematically interrogated in a size-segregated manner. In this study, we employed a refined particle size classification to collect cigarette aerosols, enabling a comprehensive assessment and comparison of the impacts exerted by cigarette aerosol extract (CAE) on SH-SY5Y, HEK293T, and A549 cells. Exposure to CAE reduced cell viability in a dose-dependent manner, with organic components having a greater impact and SH-SY5Y cells displaying lower tolerance compared to HEK293T and A549 cells. Moreover, CAE was found to cause increased oxidative stress, mitochondrial dysfunction, and increased levels of apoptosis, pyroptosis, and autophagy, leading to increased cell death. Furthermore, we found that rutin, a phytocompound with antioxidant potential, could reduce intracellular reactive oxygen species and protect against CAE-triggered cell death. These findings underscore the therapeutic potential of antioxidant drugs in mitigating the adverse effects of cigarette aerosol exposure for better public health outcomes.


Assuntos
Aerossóis , Sobrevivência Celular , Tamanho da Partícula , Material Particulado , Humanos , Material Particulado/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Nicotiana/química , Nicotiana/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Produtos do Tabaco/efeitos adversos , Poluição do Ar em Ambientes Fechados/efeitos adversos , Apoptose/efeitos dos fármacos
13.
EMBO Rep ; 23(8): e54265, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35766227

RESUMO

The aggressive nature and poor prognosis of lung cancer led us to explore the mechanisms driving disease progression. Utilizing our invasive cell-based model, we identified methylthioadenosine phosphorylase (MTAP) and confirmed its suppressive effects on tumorigenesis and metastasis. Patients with low MTAP expression display worse overall and progression-free survival. Mechanistically, accumulation of methylthioadenosine substrate in MTAP-deficient cells reduce the level of protein arginine methyltransferase 5 (PRMT5)-mediated symmetric dimethylarginine (sDMA) modification on proteins. We identify vimentin as a dimethyl-protein whose dimethylation levels drop in response to MTAP deficiency. The sDMA modification on vimentin reduces its protein abundance but trivially affects its filamentous structure. In MTAP-deficient cells, lower sDMA modification prevents ubiquitination-mediated vimentin degradation, thereby stabilizing vimentin and contributing to cell invasion. MTAP and PRMT5 negatively correlate with vimentin in lung cancer samples. Taken together, we propose a mechanism for metastasis involving vimentin post-translational regulation.


Assuntos
Neoplasias Pulmonares , Purina-Núcleosídeo Fosforilase , Humanos , Neoplasias Pulmonares/genética , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Purina-Núcleosídeo Fosforilase/metabolismo , Vimentina/genética
14.
Biomarkers ; 29(2): 100-104, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38353603

RESUMO

BACKGROUND: Serum kappa, lambda, the K/λ light chain concentrations are used for screening, diagnosis, and monitoring of patients with multiple myeloma and other plasma cell disorders. Biological variation studies conducted on healthy subjects showed that free light chains have a low within and high between-individual variation. We determined if this variation were genetically linked. METHODS: We obtained a single serum sample from 16 pairs of identical twins, 8 neonate twins, and 19 presumed directly-related siblings children, measured Κ and λ light chains and computed the Κ/λ ratio. RESULTS: As expected, Κ/λ results from each twin neonate were near identical (reflecting maternal/placental transfer). For older children and adult twins, the Κ/λ ratio form a cluster of results that were a subset of the reference range. There was one outlier, a female with a high, different from her twin sister. She likely had a monoclonal gammopathy (no followup was possible). Excluding this pair, results from neonate twins (14.4% ±10.3%) and non-neonate twins (18.0 ± 15.3%) were not significantly different. Results between non-twin siblings were more scattered (53.2%±53.4%) and different from neonate and non-neonate twin adult and children. CONCLUSION: We suggest that the Κ/λ free light chains may be genetically linked.


Assuntos
Cadeias Leves de Imunoglobulina , Irmãos , Gêmeos , Adolescente , Adulto , Criança , Feminino , Humanos , Recém-Nascido , Cadeias kappa de Imunoglobulina , Cadeias lambda de Imunoglobulina , Paraproteinemias/diagnóstico , Placenta
15.
Phys Chem Chem Phys ; 26(6): 5059-5069, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38258542

RESUMO

The decomposition of methanol-d4 (CD3OD) on Rh nanoclusters grown by the deposition of Rh vapors onto an ordered thin film of Al2O3/NiAl(100) was studied, with various surface-probe techniques and largely under near-ambient-pressure (NAP) conditions. The results showed a superior reactivity of small Rh clusters (diameter < 1.5 nm) exposed to CD3OD at 5 × 10-3-0.1 mbar at 400 K; the gaseous production of CO and D2 from decomposed methanol-d4 per Rh surface site on the small Rh clusters with diameters of ∼1.1 nm was nearly 8 times that on large ones with diameters of ∼3.5 nm. The promotion of reactivity with decreased cluster size under NAP conditions was evidently greater than that under ultrahigh vacuum conditions. Moreover, the concentration of atomic carbon (C*; where * denotes adsorbate)-a key catalyst poisoner-yielded from the dissociation of CO* from dehydrogenated methanol-d4 was significantly smaller on small clusters (diameter < 1.5 nm). The NAP size effect on methanol-d4 decomposition involved the surface hydroxyl (OH*) from the little co-adsorbed water (H2O*) that was dissociated at a probability dependent on the cluster size. H2O* was more likely dissociated into OH* on small Rh clusters, by virtue of their more reactive d-band structure, and the OH* then effectively promoted the O-D cleavage of methanol-d4, as the rate-determining step, and thus the reaction probability; on the other hand, the OH* limited CO* dissociation on small Rh clusters via both adsorbate and lateral effects. These results suggest that the superior properties of small Rh clusters in both reactivity and anti-poisoning would persist and be highly applicable under "real-world" catalysis conditions.

16.
Pediatr Nephrol ; 39(9): 2555-2568, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38233720

RESUMO

Primary glomerular diseases are rare entities. This has hampered efforts to better understand the underlying pathobiology and to develop novel safe and effective therapies. NEPTUNE is a rare disease network that is focused on patients of all ages with minimal change disease, focal segmental glomerulosclerosis, and membranous nephropathy. It is a longitudinal cohort study that collects detailed demographic, clinical, histopathologic, genomic, transcriptomic, and metabolomic data. The goal is to develop a molecular classification for these disorders that supersedes the traditional pathological features-based schema. Pediatric patients are important contributors to this ongoing project. In this review, we provide a snapshot of the children and adolescents enrolled in NEPTUNE and summarize some key observations that have been made based on the data accumulated during the study. In addition, we describe the development of NEPTUNE Match, a program that aims to leverage the multi-scalar information gathered for each individual patient to provide guidance about potential clinical trial participation based on the molecular characterization and non-invasive biomarker profile. This represents the first organized effort to apply principles of precision medicine to the treatment of patients with primary glomerular disease. NEPTUNE has proven to be an invaluable asset in the study of glomerular diseases in patients of all ages including children and adolescents.


Assuntos
Glomerulosclerose Segmentar e Focal , Humanos , Criança , Adolescente , Glomerulosclerose Segmentar e Focal/genética , Masculino , Feminino , Glomerulonefrite Membranosa/patologia , Glomerulonefrite Membranosa/genética , Estudos Longitudinais , Nefrose Lipoide/diagnóstico , Doenças Raras/genética , Doenças Raras/terapia , Doenças Raras/diagnóstico , Pré-Escolar , Estudos de Coortes , Medicina de Precisão/métodos
17.
Pediatr Nephrol ; 39(9): 2691-2701, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38671228

RESUMO

BACKGROUND: Steroids, the mainstay of treatment for nephrotic syndrome in children, have multiple adverse effects including growth suppression. METHODS: Anthropometric measurements in children < 18 years enrolled in the Nephrotic Syndrome Study Network (NEPTUNE) were collected. The longitudinal association of medication exposure and nephrotic syndrome characteristics with height z-score and growth velocity was determined using adjusted Generalized Estimating Equation regression and linear regression. RESULTS: A total of 318 children (57.2% males) with a baseline age of 7.64 ± 5.04 years were analyzed. The cumulative steroid dose was 216.4 (IQR 61.5, 652.7) mg/kg (N = 233). Overall, height z-scores were not significantly different at the last follow-up compared to baseline (- 0.13 ± 1.21 vs. - 0.23 ± 1.71, p = 0.21). In models adjusted for age, sex, and eGFR, greater cumulative steroid exposure (ß - 7.5 × 10-6, CI - 1.2 × 10-5, - 3 × 10-6, p = 0.001) and incident cases of NS (vs. prevalent) (ß - 1.1, CI - 2.22, - 0.11, p = 0.03) were significantly associated with lower height z-scores over time. Rituximab exposure was associated with higher height z-scores (ß 0.16, CI 0.04, 0.29, p = 0.01) over time. CONCLUSION: Steroid dose was associated with lower height z-score, while rituximab use was associated with higher height z-score.


Assuntos
Estatura , Síndrome Nefrótica , Humanos , Síndrome Nefrótica/tratamento farmacológico , Masculino , Feminino , Criança , Pré-Escolar , Estatura/efeitos dos fármacos , Adolescente , Transtornos do Crescimento/etiologia , Transtornos do Crescimento/tratamento farmacológico , Transtornos do Crescimento/diagnóstico , Estudos Longitudinais , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Rituximab/administração & dosagem , Rituximab/efeitos adversos
18.
Pediatr Nephrol ; 39(7): 2161-2170, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38319465

RESUMO

BACKGROUND: In the current study, longitudinal BP and lipid measurements were examined in a NEPTUNE cohort of children with newly diagnosed nephrotic syndrome (cNEPTUNE). We hypothesized that hypertensive BP and dyslipidemia would persist in children with nephrotic syndrome, regardless of steroid treatment response. METHODS: A multi-center longitudinal observational analysis of data obtained from children < 19 years of age with new onset nephrotic syndrome enrolled in the Nephrotic Syndrome Study Network (cNEPTUNE) was conducted. BP and lipid data were examined over time stratified by disease activity and steroid exposure. Generalized estimating equation regressions were used to find determinants of hypertensive BP and dyslipidemia. RESULTS: Among 122 children, the prevalence of hypertensive BP at any visit ranged from 17.4% to 57.4%, while dyslipidemia prevalence ranged from 40.0% to 96.2% over a median of 30 months of follow-up. Hypertensive BP was found in 46.2% (116/251) of study visits during active disease compared with 31.0% (84/271) of visits while in remission. Dyslipidemia was present in 88.2% (120/136) of study visits during active disease and in 66.0% (101/153) while in remission. Neither dyslipidemia nor hypertensive BP were significantly different with/without medication exposure (steroids and/or CNI). In regression analysis, male sex and urine protein:creatinine ratio (UPC) were significant determinants of hypertensive BP over time, while eGFR was found to be a determinant of dyslipidemia over time. CONCLUSIONS: Results demonstrate persistent hypertensive BPs and unfavorable lipid profiles in the cNEPTUNE cohort regardless of remission status or concurrent steroid or calcineurin inhibitor treatment.


Assuntos
Pressão Sanguínea , Dislipidemias , Hipertensão , Síndrome Nefrótica , Humanos , Síndrome Nefrótica/urina , Síndrome Nefrótica/tratamento farmacológico , Síndrome Nefrótica/complicações , Síndrome Nefrótica/epidemiologia , Síndrome Nefrótica/sangue , Masculino , Criança , Feminino , Estudos Longitudinais , Hipertensão/epidemiologia , Hipertensão/tratamento farmacológico , Hipertensão/diagnóstico , Hipertensão/etiologia , Pré-Escolar , Dislipidemias/epidemiologia , Dislipidemias/sangue , Adolescente , Lipídeos/sangue , Prevalência , Lactente
19.
Cereb Cortex ; 33(5): 1693-1707, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-35512682

RESUMO

Establishing neuronal circuits requires interactions between pre- and postsynaptic neurons. While presynaptic neurons were shown to play instructive roles for the postsynaptic neurons, how postsynaptic neurons provide feedback to regulate the presynaptic neuronal development remains elusive. To elucidate the mechanisms for circuit formation, we study the development of barrel cortex (the primary sensory cortex, S1), whose development is instructed by presynaptic thalamocortical axons (TCAs). In the first postnatal weeks, TCA terminals arborize in layer (L) 4 to fill in the barrel center, but it is unclear how TCA development is regulated. Here, we reported that the deletion of Lhx2 specifically in the cortical neurons in the conditional knockout (cKO) leads to TCA arborization defects, which is accompanied with deficits in sensory-evoked and spontaneous cortical activities and impaired lesion-induced plasticity following early whisker follicle ablation. Reintroducing Lhx2 back in L4 neurons in cKO ameliorated TCA arborization and plasticity defects. By manipulating L4 neuronal activity, we further demonstrated that Lhx2 induces TCA arborization via an activity-dependent mechanism. Additionally, we identified the extracellular signaling protein Sema7a as an activity-dependent downstream target of Lhx2 in regulating TCA branching. Thus, we discovered a bottom-up feedback mechanism for the L4 neurons to regulate TCA development.


Assuntos
Neurônios , Tálamo , Retroalimentação , Tálamo/fisiologia , Neurônios/fisiologia , Axônios/fisiologia , Transdução de Sinais , Córtex Somatossensorial/fisiologia
20.
Dig Dis Sci ; 69(7): 2655-2666, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38656415

RESUMO

BACKGROUND: Diminished muscle protein synthesis in cirrhosis leads to reduced strength and mass, impacting daily activities and overall quality of life. AIMS: This study aimed to examine the effectiveness of exercise intervention in body composition, exercise capacity, fatigue, and quality of life in patients with liver cirrhosis. METHODS: A systematic search of medical databases, including PubMed, Embase, Cochrane, and CINAHL, was executed from their inception to November 2022. The inclusion criteria were randomized controlled trials comparing exercise interventions with a control group that did not receive exercise interventions. RESULTS: From the initially identified 2,565 articles, eight studies with a total of 220 patients were eligible for inclusion in this meta-analysis. According to the meta-analysis, exercise significantly improved the six-minute walk distance (6MWD) by 68.93 m (95% CI 14.29-123.57) compared to the control group. Furthermore, the subgroup analysis revealed that combing exercise with amino acid supplementation had a greater positive effect on the 6MWD (MD = 144.72, 95% CI 87.44-202.01). Exercise also significantly increased thigh circumference (MD = 1.26, 95% CI 0.12-2.39) and the thigh ultrasound average compression index (MD = 0.07, 95% CI 0.00-0.14). Moreover, exercise significantly decreased fatigue levels by 0.7 points in patients with liver cirrhosis (95% CI 0.38-1.03). However, no significant effects were observed on body mass index (BMI), fat mass, fat-free mass, and quality of life. CONCLUSIONS: Exercise can improve exercise capacity, thigh muscle thickness, and fatigue in patients with cirrhosis, but it does not have a significant impact on fat mass, BMI, or quality of life.


Assuntos
Composição Corporal , Terapia por Exercício , Tolerância ao Exercício , Fadiga , Cirrose Hepática , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Terapia por Exercício/métodos , Tolerância ao Exercício/fisiologia , Fadiga/etiologia , Fadiga/fisiopatologia , Cirrose Hepática/complicações , Cirrose Hepática/fisiopatologia , Cirrose Hepática/terapia , Cirrose Hepática/psicologia , Resultado do Tratamento
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