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1.
Mol Cell ; 75(3): 644-660.e5, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398325

RESUMO

Cell-cell communication via ligand-receptor signaling is a fundamental feature of complex organs. Despite this, the global landscape of intercellular signaling in mammalian liver has not been elucidated. Here we perform single-cell RNA sequencing on non-parenchymal cells isolated from healthy and NASH mouse livers. Secretome gene analysis revealed a highly connected network of intrahepatic signaling and disruption of vascular signaling in NASH. We uncovered the emergence of NASH-associated macrophages (NAMs), which are marked by high expression of triggering receptors expressed on myeloid cells 2 (Trem2), as a feature of mouse and human NASH that is linked to disease severity and highly responsive to pharmacological and dietary interventions. Finally, hepatic stellate cells (HSCs) serve as a hub of intrahepatic signaling via HSC-derived stellakines and their responsiveness to vasoactive hormones. These results provide unprecedented insights into the landscape of intercellular crosstalk and reprogramming of liver cells in health and disease.


Assuntos
Comunicação Celular/genética , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Análise de Sequência de RNA , Animais , Reprogramação Celular/genética , Modelos Animais de Doenças , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Humanos , Ligantes , Fígado/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais/genética , Análise de Célula Única
2.
Nucleic Acids Res ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922686

RESUMO

The human DNA repair factor CtIP helps to initiate the resection of double-stranded DNA breaks for repair by homologous recombination, in part through its ability to bind and bridge DNA molecules. However, CtIP is a natively disordered protein that bears no apparent similarity to other DNA-binding proteins and so the structural basis for these activities remains unclear. In this work, we have used bulk DNA binding, single molecule tracking, and DNA bridging assays to study wild-type and variant CtIP proteins to better define the DNA binding domains and the effects of mutations associated with inherited human disease. Our work identifies a monomeric DNA-binding domain in the C-terminal region of CtIP. CtIP binds non-specifically to DNA and can diffuse over thousands of nucleotides. CtIP-mediated bridging of distant DNA segments is observed in single-molecule magnetic tweezers experiments. However, we show that binding alone is insufficient for DNA bridging, which also requires tetramerization via the N-terminal domain. Variant CtIP proteins associated with Seckel and Jawad syndromes display impaired DNA binding and bridging activities. The significance of these findings in the context of facilitating DNA break repair is discussed.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38868940

RESUMO

BACKGROUND: Plasma concentration of PAI-1 (plasminogen activator inhibitor-1) correlates with arterial stiffness. Vascular smooth muscle cells (SMCs) express PAI-1, and the intrinsic stiffness of SMCs is a major determinant of total arterial stiffness. We hypothesized that PAI-1 promotes SMC stiffness by regulating the cytoskeleton and that pharmacological inhibition of PAI-1 decreases SMC and aortic stiffness. METHODS: PAI-039, a specific inhibitor of PAI-1, and small interfering RNA were used to inhibit PAI-1 expression in cultured human SMCs. Effects of PAI-1 inhibition on SMC stiffness, F-actin (filamentous actin) content, and cytoskeleton-modulating enzymes were assessed. WT (wild-type) and PAI-1-deficient murine SMCs were used to determine PAI-039 specificity. RNA sequencing was performed to determine the effects of PAI-039 on SMC gene expression. In vivo effects of PAI-039 were assessed by aortic pulse wave velocity. RESULTS: PAI-039 significantly reduced intrinsic stiffness of human SMCs, which was accompanied by a significant decrease in cytoplasmic F-actin content. PAI-1 gene knockdown also decreased cytoplasmic F-actin. PAI-1 inhibition significantly increased the activity of cofilin, an F-actin depolymerase, in WT murine SMCs, but not in PAI-1-deficient SMCs. RNA-sequencing analysis suggested that PAI-039 upregulates AMPK (AMP-activated protein kinase) signaling in SMCs, which was confirmed by Western blotting. Inhibition of AMPK prevented activation of cofilin by PAI-039. In mice, PAI-039 significantly decreased aortic stiffness and tunica media F-actin content without altering the elastin or collagen content. CONCLUSIONS: PAI-039 decreases intrinsic SMC stiffness and cytoplasmic stress fiber content. These effects are mediated by AMPK-dependent activation of cofilin. PAI-039 also decreases aortic stiffness in vivo. These findings suggest that PAI-1 is an important regulator of the SMC cytoskeleton and that pharmacological inhibition of PAI-1 has the potential to prevent and treat cardiovascular diseases involving arterial stiffening.

4.
Am J Physiol Heart Circ Physiol ; 326(1): H270-H277, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37999645

RESUMO

Endothelial insulin resistance represents a causal factor in the pathogenesis of type 2 diabetes (T2D) and vascular disease, thus the need to identify molecular mechanisms underlying defects in endothelial insulin signaling. We previously have shown that a disintegrin and metalloproteinase-17 (ADAM17) is increased while insulin receptor α-subunit (IRα) is decreased in the vasculature of patients with T2D, leading to impaired insulin-induced vasodilation. We have also demonstrated that ADAM17 sheddase activity targets IRα; however, the mechanisms driving endothelial ADAM17 activity in T2D are largely unknown. Herein, we report that externalization of phosphatidylserine (PS) to the outer leaflet of the plasma membrane causes ADAM17-mediated shedding of IRα and blunting of insulin signaling in endothelial cells. Furthermore, we demonstrate that endothelial PS externalization is mediated by the phospholipid scramblase anoctamin-6 (ANO6) and that this process can be stimulated by neuraminidase, a soluble enzyme that cleaves sialic acid residues. Of note, we demonstrate that men and women with T2D display increased levels of neuraminidase activity in plasma, relative to age-matched healthy individuals, and this occurs in conjunction with increased ADAM17 activity and impaired leg blood flow responses to endogenous insulin. Collectively, this work reveals the neuraminidase-ANO6-ADAM17 axis as a novel potential target for restoring endothelial insulin sensitivity in T2D.NEW & NOTEWORTHY This work provides the first evidence that neuraminidase, an enzyme increased in the circulation of men and women with type 2 diabetes (T2D), promotes anoctamin-6 (ANO6)-dependent externalization of phosphatidylserine in endothelial cells, which in turn leads to activation of a disintegrin and metalloproteinase-17 (ADAM17) and consequent shedding of the insulin receptor-α from the cell surface. Hence, this work supports that consideration should be given to the neuraminidase-ANO6-ADAM17 axis as a novel potential target for restoring endothelial insulin sensitivity in T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Masculino , Humanos , Feminino , Células Endoteliais/metabolismo , Receptor de Insulina/metabolismo , Fosfatidilserinas/metabolismo , Neuraminidase/metabolismo , Insulina/metabolismo , Desintegrinas , Proteína ADAM17/metabolismo , Anoctaminas/metabolismo
5.
Plant Cell Environ ; 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38881245

RESUMO

This study determines the functional role of the plant ultraviolet-B radiation (UV-B) photoreceptor, UV RESISTANCE LOCUS 8 (UVR8) under natural conditions using a large-scale 'synchronized-genetic-perturbation-field-experiment'. Laboratory experiments have demonstrated a role for UVR8 in UV-B responses but do not reflect the complexity of outdoor conditions where 'genotype × environment' interactions can mask laboratory-observed responses. Arabidopsis thaliana knockout mutant, uvr8-7, and the corresponding Wassilewskija wild type, were sown outdoors on the same date at 21 locations across Europe, ranging from 39°N to 67°N latitude. Growth and climatic data were monitored until bolting. At the onset of bolting, rosette size, dry weight, and phenolics and glucosinolates were quantified. The uvr8-7 mutant developed a larger rosette and contained less kaempferol glycosides, quercetin glycosides and hydroxycinnamic acid derivatives than the wild type across all locations, demonstrating a role for UVR8 under field conditions. UV effects on rosette size and kaempferol glycoside content were UVR8 dependent, but independent of latitude. In contrast, differences between wild type and uvr8-7 in total quercetin glycosides, and the quercetin-to-kaempferol ratio decreased with increasing latitude, that is, a more variable UV response. Thus, the large-scale synchronized approach applied demonstrates a location-dependent functional role of UVR8 under natural conditions.

6.
Am J Perinatol ; 41(S 01): e1451-e1458, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38134940

RESUMO

OBJECTIVE: This study aimed to examine fetal and neonatal inflammatory and neurologic complications associated with maternal coronavirus disease 2019 (COVID-19) infection. STUDY DESIGN: Case-series using a convenience sample of neonates cared for in a large referral-based children's hospital neonatal intensive care unit between September 2021 and May 2022. RESULTS: We identified seven neonates with exposure to maternal severe acute respiratory syndrome related coronavirus 2 (SARS-CoV-2) and a presentation consistent with inflammatory complications. All had some degree of neurologic injury with neuroimaging findings including restricted diffusion indicating injury in the white matter, cortex, deep gray structures, and splenium of the corpus callosum as well as intracranial hemorrhage. In addition, many infants had cytopenia and abnormal coagulation studies. Placental pathology, when available, revealed inflammation, clot with calcifications, and hematomas with associated infarcts. CONCLUSION: Neonates born to mothers with SARS-CoV-2, even when negative for the virus themselves, may have complications consistent with a systemic inflammatory syndrome. Placental pathology as well as neurologic imaging in infants with neurologic findings may help to support this diagnosis. KEY POINTS: · A systemic inflammatory response may cause illness in babies born to mothers with a history of COVID-19.. · Inflammatory markers and placental pathology are helpful in supporting this diagnosis.. · Consider neuroimaging in infants of mothers with a history of COVID-19 with neurologic findings..


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , SARS-CoV-2 , Síndrome de Resposta Inflamatória Sistêmica , Humanos , COVID-19/complicações , Feminino , Gravidez , Recém-Nascido , Complicações Infecciosas na Gravidez/virologia , Masculino , Placenta/patologia , Placenta/virologia , Adulto , Transmissão Vertical de Doenças Infecciosas , Neuroimagem
7.
Eur Heart J ; 44(48): 5110-5124, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37941449

RESUMO

BACKGROUND AND AIMS: While endomyocardial biopsy (EMB) is recommended in adult patients with fulminant myocarditis, the clinical impact of its timing is still unclear. METHODS: Data were collected from 419 adult patients with clinically suspected fulminant myocarditis admitted to intensive care units across 36 tertiary centres in 15 countries worldwide. The diagnosis of myocarditis was histologically proven in 210 (50%) patients, either by EMB (n = 183, 44%) or by autopsy/explanted heart examination (n = 27, 6%), and clinically suspected cardiac magnetic resonance imaging confirmed in 96 (23%) patients. The primary outcome of survival free of heart transplantation (HTx) or left ventricular assist device (LVAD) at 1 year was specifically compared between patients with early EMB (within 2 days after intensive care unit admission, n = 103) and delayed EMB (n = 80). A propensity score-weighted analysis was done to control for confounders. RESULTS: Median age on admission was 40 (29-52) years, and 322 (77%) patients received temporary mechanical circulatory support. A total of 273 (65%) patients survived without HTx/LVAD. The primary outcome was significantly different between patients with early and delayed EMB (70% vs. 49%, P = .004). After propensity score weighting, the early EMB group still significantly differed from the delayed EMB group in terms of survival free of HTx/LVAD (63% vs. 40%, P = .021). Moreover, early EMB was independently associated with a lower rate of death or HTx/LVAD at 1 year (odds ratio of 0.44; 95% confidence interval: 0.22-0.86; P = .016). CONCLUSIONS: Endomyocardial biopsy should be broadly and promptly used in patients admitted to the intensive care unit for clinically suspected fulminant myocarditis.


Assuntos
Transplante de Coração , Miocardite , Adulto , Humanos , Miocardite/complicações , Biópsia/métodos , Cateterismo Cardíaco , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Miocárdio/patologia
8.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38710467

RESUMO

INTRODUCTION: Granulocyte and monocyte adsorptive apheresis (GMA) removes neutrophils and monocytes from peripheral blood, preventing their incorporation into the inflamed tissue also influencing cytokine balance. Published therapeutic efficacy in ulcerative colitis (UC) is more consistent than in Crohn's disease (CD). We assessed clinical efficacy of GMA in UC and CD 4 weeks after last induction session, at 3 and 12 months, sustained remission and corticosteroid-free remission. PATIENTS AND METHOD: Retrospective observational study of UC and CD patients treated with GMA. Partial Disease Activity Index-DAIp in UC and Harvey-Bradshaw Index-HBI in CD assessed efficacy of Adacolumn® with induction and optional maintenance sessions. RESULTS: We treated 87 patients (CD-25, UC-62), 87.3% corticosteroid-dependent (CSD), 42.5% refractory/intolerant to immunomodulators. In UC, remission and response were 32.2% and 19.3% after induction, 35.5% and 6.5% at 12 weeks and 29% and 6.5% at 52 weeks. In CD, remission rates were 60%, 52% and 40% respectively. In corticosteroid-dependent and refractory or intolerant to INM patients (UC-41, CD-14), 68.3% of UC achieved remission or response after induction, 51.2% at 12 weeks and 46.3% at 52 weeks, and 62.3%, 64.3% and 42.9% in CD. Maintained remission was achieved by 66.6% in CD and 53.1% in UC. Up to 74.5% of patients required corticosteroids at some timepoint. Corticosteroid-free response/remission was 17.7% in UC and 24% in CD. CONCLUSIONS: GMA is a good therapeutic tool for both in UC and CD patients. In corticosteroid-dependent and refractory or intolerant to INM patients it avoids biological therapy or surgery in up to 40% of them in one year.

9.
Mol Pharmacol ; 104(4): 154-163, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37536953

RESUMO

Cytochrome P450 3A4 (CYP3A4) is the dominant P450 involved in human xenobiotic metabolism. Competition for CYP3A4 therefore underlies several adverse drug-drug interactions. Despite its clinical significance, the mechanisms CYP3A4 uses to bind diverse ligands remain poorly understood. Highly monodisperse CYP3A4 embedded in anionic lipoprotein nanodiscs containing an equal mixture of 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) were used to determine which of the limiting kinetic schemes that include protein conformational change, conformational selection (CS) or induced fit (IF), best described the binding of four known irreversible inhibitors. Azamulin, retapamulin, pleuromutilin, and mibrefadil binding to CYP3A4 nanodiscs conformed to a single-site binding model. Exponential fits of stopped-flow UV-visible absorption spectroscopy data supported multiple-step binding mechanisms. Trends in the rates of relaxation to equilibrium with increasing ligand concentrations were ambiguous as to whether IF or CS was involved; however, global fitting and consideration of the rate constants favored an IF mechanism. In the case of mibrefadil, a transient complex was observed in the stopped-flow UV-visible experiment, definitively assigning the presence of IF in ligand binding. While these studies only consider a small region of CYP3A4's vast ligand space, they provide kinetic evidence that CYP3A4 can use an IF mechanism. SIGNIFICANCE STATEMENT: CYP3A4 is capable of oxidizing numerous xenobiotics, including many drugs. Such promiscuity could not be achieved without conformational changes to accommodate diverse substrates. It is unknown whether conformational heterogeneity is present before (conformational selection) or after (induced fit) ligand binding. Stopped-flow measurements of suicide inhibitors binding to nanodisc-embedded CYP3A4 combined with sophisticated numerical analyses support that induced fit better describes ligand binding to this important enzyme.


Assuntos
Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450 , Humanos , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Ligantes , Conformação Molecular
10.
Int J Cancer ; 152(3): 496-503, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36214794

RESUMO

Two pathways have been described for vulvar squamous cell carcinomas (VSCC), one associated with human papillomavirus (HPV), and the other HPV-independent. We compared the etiopathogenic features of a series of VSCC from Mozambique, a sub-Saharan country with high prevalence of HPV and HIV, with those of Spain, a European country with low prevalence of HPV and HIV. All VSCC diagnosed at the two institutions from January 2018 to December 2020 were included (n = 35 and n = 41, respectively). HPV DNA detection and genotyping, and immunohistochemistry for p16 and p53 were performed. Tumors showing p16 positive staining and/or HPV DNA positivity were considered HPV-associated. 34/35 tumors (97%) from Mozambique and 8/41 (19%) from Spain were HPV-associated (P < .001). Mean age of the patients from Mozambique and Spain was 45 ± 12 and 72 ± 14, respectively (P < .001). No differences were found in terms of HPV genotypes or multiple HPV infection rates. 1/35 tumors (3%) from Mozambique and 29/41 (70%) from Spain showed abnormal p53 immunostaining (P < .001). In contrast with the predominance of HPV-independent VSCC affecting old women in Europe, most VSCC in sub-Saharan Africa are HPV-associated and arise in young women. This data may have important consequences for primary prevention of VSCC worldwide.


Assuntos
Carcinoma de Células Escamosas , Infecções por HIV , Infecções por Papillomavirus , Neoplasias Vulvares , Humanos , Feminino , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/diagnóstico , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Neoplasias Vulvares/epidemiologia , Neoplasias Vulvares/etiologia , Neoplasias Vulvares/diagnóstico , Papillomaviridae/genética , Papillomaviridae/metabolismo , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/metabolismo , Infecções por HIV/complicações , Moçambique/epidemiologia , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo
11.
J Mol Evol ; 91(6): 882-896, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38102415

RESUMO

In the year 2002, DNA loss model (DNA-LM) postulated that neuropeptide genes to emerged through codons loss via the repair of damaged DNA from ancestral gene namely Neuropeptide Precursor Predictive (NPP), which organization correspond two or more neuropeptides precursors evolutive related. The DNA-LM was elaborated according to amino acids homology among LWamide, APGWamide, red pigment-concentrating hormone (RPCH), adipokinetic hormones (AKHs) and in silico APGW/RPCH NPPAPGW/AKH NPP were proposed. With the above principle, it was proposed the evolution of corazonin (CRZ), gonadotropin-releasing hormone (GnRH), AKH, and AKH/CRZ (ACP), but any NPP never was considered. However, the evolutive relation via DNA-LM among these neuropeptides precursors not has been established yet. Therefore, the transcriptomes from crabs Callinectes toxotes and Callinectes arcuatus were used to characterized ACP and partial CRZ precursors, respectively. BLAST alignment with APGW/RPCH NPP and APGW/AKH NPP allow identified similar NPP in the rotifer Brachionus plicatilis and other invertebrates. Moreover, three bioinformatics algorithms and manual verification were used to purify 13,778 sequences, generating a database with 719 neuropeptide precursors. Phylogenetic trees with the DNA-LM parameters showed that some ACP, CRZ, AKH2 and two NPP share nodes with GnRH from vertebrates and some of this neuropeptide had nodes in invertebrates. Whereas the phylogenetic tree with standard parameters do not showed previous node pattern. Robinson-Foulds metric corroborates the differences among phylogenetic trees. Homology relationship showed four putative orthogroups; AKH4, CRZ, and protostomes GnRH had individual group. This is the first demonstration of NPP in species and would explain the evolution neuropeptide families by the DNA-LM.


Assuntos
Hormônio Liberador de Gonadotropina , Neuropeptídeos , Humanos , Animais , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Filogenia , Evolução Molecular , Neuropeptídeos/genética , Neuropeptídeos/química , Neuropeptídeos/metabolismo , Invertebrados/genética , DNA/metabolismo
12.
Am J Physiol Heart Circ Physiol ; 325(6): H1337-H1353, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37801046

RESUMO

Neuraminidases cleave sialic acids from glycocalyx structures and plasma neuraminidase activity is elevated in type 2 diabetes (T2D). Therefore, we hypothesize circulating neuraminidase degrades the endothelial glycocalyx and diminishes flow-mediated dilation (FMD), whereas its inhibition restores shear mechanosensation and endothelial function in T2D settings. We found that compared with controls, subjects with T2D have higher plasma neuraminidase activity, reduced plasma nitrite concentrations, and diminished FMD. Ex vivo and in vivo neuraminidase exposure diminished FMD and reduced endothelial glycocalyx presence in mouse arteries. In cultured endothelial cells, neuraminidase reduced glycocalyx coverage. Inhalation of the neuraminidase inhibitor, zanamivir, reduced plasma neuraminidase activity, enhanced endothelial glycocalyx length, and improved FMD in diabetic mice. In humans, a single-arm trial (NCT04867707) of zanamivir inhalation did not reduce plasma neuraminidase activity, improved glycocalyx length, or enhanced FMD. Although zanamivir plasma concentrations in mice reached 225.8 ± 22.0 ng/mL, in humans were only 40.0 ± 7.2 ng/mL. These results highlight the potential of neuraminidase inhibition for ameliorating endothelial dysfunction in T2D and suggest the current Food and Drug Administration-approved inhaled dosage of zanamivir is insufficient to achieve desired outcomes in humans.NEW & NOTEWORTHY This work identifies neuraminidase as a key mediator of endothelial dysfunction in type 2 diabetes that may serve as a biomarker for impaired endothelial function and predictive of development and progression of cardiovascular pathologies associated with type 2 diabetes (T2D). Data show that intervention with the neuraminidase inhibitor zanamivir at effective plasma concentrations may represent a novel pharmacological strategy for restoring the glycocalyx and ameliorating endothelial dysfunction.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Doenças Vasculares , Camundongos , Humanos , Animais , Zanamivir/farmacologia , Neuraminidase/química , Neuraminidase/farmacologia , Células Endoteliais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia
13.
Yeast ; 40(7): 265-275, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37170862

RESUMO

Debaryomyces hansenii is a halotolerant/halophilic yeast usually found in salty environments. The yeast accumulated sodium at high concentrations, which improved growth in salty media. In contrast, lithium was toxic even at low concentrations and its presence prevented cell proliferation. To analyse the responses to both cations, metabolite levels, enzymatic activities and gene expression were determined, showing that NaCl and LiCl trigger different cellular responses. At high concentrations of NaCl (0.5 or 1.5 M) cells accumulated higher amounts of the intermediate metabolites glyoxylate and malate and, at the same time, the levels of intracellular oxoglutarate decreased. Additionally, 0.5 M NaCl increased the activity of the enzymes isocitrate lyase and malate synthase involved in the synthesis of glyoxylate and malate respectively and decreased the activity of isocitrate dehydrogenase. Moreover, transcription of the genes coding for isocitrate lyase and malate synthase was activated by NaCl. Also, cells accumulated phosphate upon NaCl exposure. None of these effects was provoked when LiCl (0.1 or 0.3 M) was used instead of NaCl. Lithium induced accumulation of higher amounts of oxoglutarate and decreased the concentrations of glyoxylate and malate to non-detectable levels. Cells incubated with lithium also showed higher activity of the isocitrate dehydrogenase and neither increased isocitrate lyase and malate synthase activities nor the transcription of the corresponding genes. In summary, we show that sodium, but not lithium, up regulates the shunt of the glyoxylic acid in D. hansenii and we propose that this is an important metabolic adaptation to thrive in salty environments.


Assuntos
Debaryomyces , Sódio , Cloreto de Sódio/farmacologia , Malato Sintase/genética , Malato Sintase/metabolismo , Isocitrato Liase/genética , Isocitrato Liase/metabolismo , Malatos , Debaryomyces/metabolismo , Saccharomyces cerevisiae/metabolismo , Isocitrato Desidrogenase/genética , Carbono , Ácidos Cetoglutáricos , Glioxilatos/metabolismo
14.
Am J Physiol Regul Integr Comp Physiol ; 324(3): R293-R304, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36622084

RESUMO

Vascular insulin resistance, a major characteristic of obesity and type 2 diabetes (T2D), manifests with blunting of insulin-induced vasodilation. Although there is evidence that females are more whole body insulin sensitive than males in the healthy state, whether sex differences exist in vascular insulin sensitivity is unclear. Also uncertain is whether weight loss can reestablish vascular insulin sensitivity in T2D. The purpose of this investigation was to 1) establish if sex differences in vasodilatory responses to insulin exist in absence of disease, 2) determine whether female sex affords protection against the development of vascular insulin resistance with long-term overnutrition and obesity, and 3) examine if diet-induced weight loss can restore vascular insulin sensitivity in men and women with T2D. First, we show in healthy mice and humans that sex does not influence insulin-induced femoral artery dilation and insulin-stimulated leg blood flow, respectively. Second, we provide evidence that female mice are protected against impairments in insulin-induced dilation caused by overnutrition-induced obesity. Third, we show that men and women exhibit comparable levels of vascular insulin resistance when T2D develops but that diet-induced weight loss is effective at improving insulin-stimulated leg blood flow, particularly in women. Finally, we provide indirect evidence that these beneficial effects of weight loss may be mediated by a reduction in endothelin-1. In aggregate, the present data indicate that female sex confers protection against obesity-induced vascular insulin resistance and provide supportive evidence that, in women with T2D, vascular insulin resistance can be remediated with diet-induced weight loss.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Humanos , Feminino , Masculino , Camundongos , Animais , Resistência à Insulina/fisiologia , Insulina , Obesidade , Redução de Peso , Artéria Femoral , Dieta
15.
Respir Res ; 24(1): 223, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715261

RESUMO

BACKGROUND: Achieving and maintaining a low-risk profile is associated with favorable outcome in pulmonary arterial hypertension (PAH). The effects of treatment on risk profile are variable among patients. OBJECTIVE: To Identify variables that might predict the response to treatment with phosphodiesterase-5 inhibitors (PDE-5i) in PAH. METHODS: We carried out a cohort analysis of the Spanish PAH registry in 830 patients diagnosed with PAH that started PDE5i treatment and had > 1 year follow-up. 644 patients started PDE-5i either in mono- or add-on therapy and 186 started combined treatment with PDE-5i and endothelin receptor antagonist (ERA). Responders were considered when at 1 year they: (1) were alive; (2) did not present clinical worsening; and (3) improved European Society of Cardiology/European Respiratory Society (ESC/ERS) risk score or remained in low-risk. Univariate and multivariate logistic regression models were used to analyze variables associated with a favorable response. RESULTS: Two hundred and ten patients (33%) starting PDE-5i alone were classified as responders, irrespective of whether it was mono- or add-on therapy. In addition to known predictors of PAH outcome (low-risk at baseline, younger age), male sex and diagnosis of portopulmonary hypertension (PoPH) or HIV-PAH were independent predictors of favorable response to PDE-5i. Diffusing capacity for carbon monoxide (DLco) ≤ 40% of predicted was associated with an unfavorable response. When PDE-5i were used in upfront combination, 58% of patients were responders. In this group, diagnosis of idiopathic PAH (IPAH) was an independent predictor of favorable response, whereas connective tissue disease-PAH was associated with an unfavorable response. CONCLUSION: Male sex and diagnosis of PoPH or HIV-PAH are predictors of favorable effect of PDE-5i on risk profile when used as mono- or add-on therapy. Patients with IPAH respond more favorably to PDE-5i when used in upfront combination. These results identify patient profiles that may respond favorably to PDE-5i in monotherapy and those who might benefit from alternative treatment strategies.


Assuntos
Infecções por HIV , Hipertensão Arterial Pulmonar , Humanos , Masculino , Hipertensão Arterial Pulmonar/diagnóstico , Hipertensão Arterial Pulmonar/tratamento farmacológico , Hipertensão Arterial Pulmonar/epidemiologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5 , Inibidores da Fosfodiesterase 5/uso terapêutico , Hipertensão Pulmonar Primária Familiar , Sistema de Registros
16.
Environ Sci Technol ; 57(40): 14950-14960, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37753594

RESUMO

Calcium phosphate nanoparticles were doped with zinc ions to produce multifunctional nanomaterials for efficient agronomic fortification and protection of plants. The resulting round-shaped nanoparticles (nanoZn) were composed of 20.3 wt % Ca, 14.8 wt % P, and 13.4 wt % Zn and showed a pH-controlled solubility. NanoZn were stable in aqueous solutions at neutral pH but dissolved in citric acid at pH 4.5 (i.e., the pH inside tomato fruits), producing a pH-responsive delivery of the essential nutrients Ca, P, and Zn. In fact, the foliar application of nanoZn on tomato plants provided tomatoes with the highest Zn, Ca, and P contents (causing, respectively, a 65, 65, and 15% increase with respect to a conventional treatment with ZnSO4) and the highest yields. Additionally, nanoZn (100 ppm of Zn) inhibited in vitro the growth of Pseudomonas syringae (Ps), the main cause of bacterial speck, and significantly reduced Ps incidence and mortality in tomato seeds, previously inoculated with the pathogen. Therefore, nanoZn present dual agricultural applicability, enriching crops with nutrients with important metabolic functions in humans and simultaneously protecting the plants against important bacterial-based diseases, with considerable negative impact in crop production.


Assuntos
Nanoestruturas , Solanum lycopersicum , Humanos , Biofortificação/métodos , Zinco , Produtos Agrícolas
17.
Endocr Pract ; 29(5): 362-367, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36828282

RESUMO

OBJECTIVE: Studies have found a significant decrease in bone mineral density (BMD) in individuals with type 1 diabetes (T1D) compared to healthy controls. Factors associated with this phenomenon have yet to be defined; therefore, this study aimed to explore the association of glycated hemoglobin (HbA1c), disease duration, albuminuria, and glomerular filtration rate with BMD in adults with T1D. METHODS: A cross-sectional study was carried out in tertiary care center. BMD analysis was performed by dual x-ray absorptiometry. Linear models were constructed considering variables associated with BMD. Approval from the ethics committees and informed consent were obtained. RESULTS: We included 128 participants, of whom 59% were women, and 16% had menopause. The median age was 33 (26-42) years. The average age of diabetes diagnosis was 15.3 ± 6.3 years, and the median disease duration was 19.5 (12-27) years. In the adjusted analysis, higher albuminuria (P < .01) and disease duration (P < .05) were associated with a lower BMD in the femoral neck and total hip, independently of age, sex, and body mass index (BMI). Higher HbA1c (P < .01) was associated with a lower spine BMD after adjustment for age, sex, and BMI. CONCLUSION: Studied factors specific to T1D, including albuminuria, disease duration, and HbA1c have an association with BMD regardless of BMI, age, and sex.


Assuntos
Densidade Óssea , Diabetes Mellitus Tipo 1 , Adulto , Humanos , Feminino , Criança , Adolescente , Adulto Jovem , Masculino , Hemoglobinas Glicadas , Diabetes Mellitus Tipo 1/complicações , Estudos Transversais , Albuminúria/complicações , Absorciometria de Fóton , Colo do Fêmur/diagnóstico por imagem
18.
Appl Opt ; 62(12): 2970-2977, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37133142

RESUMO

A study on the classification of copper concentrates relevant to the copper refining industry is performed by means of reflectance hyperspectral images in the visible and near infrared (VIS-NIR) bands (400-1000 nm) and in the short-wave infrared (SWIR) (900-1700 nm) band. A total of 82 copper concentrate samples were press compacted into 13-mm-diameter pellets, and their mineralogical composition was characterized via quantitative evaluation of minerals and scanning electron microscopy. The most representative minerals contained in these pellets are bornite, chalcopyrite, covelline, enargite, and pyrite. Three databases (VIS-NIR, SWIR, and VIS-NIR-SWIR) containing a collection of average reflectance spectra computed from 9×9p i x e l neighborhoods in each pellet hyperspectral image are compiled to train the classification models. The classification models tested in this work are a linear discriminant classifier and two non-linear classifiers, a quadratic discriminant classifier, and a fine K-nearest neighbor classifier (FKNNC). The results obtained show that the joint use of VIS-NIR and SWIR bands allows for the accurate classification of similar copper concentrates that contain only minor differences in their mineralogical composition. Specifically, among the three tested classification models, the FKNNC performs the best in terms of overall classification accuracy, achieving 93.4% accuracy in the test set when only VIS-NIR data are used to construct the classification model, up to 80.5% using only SWIR data, and up to 97.6% using both VIS-NIR and SWIR bands together.

19.
Dyslexia ; 29(4): 330-346, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37783574

RESUMO

Detecting students with reading difficulties (RD) is particularly important in the context of the Response to Intervention (RTI) model, in terms of both research and professional practice. However, there is no unanimous agreement on the best procedure to carry it out. In addition, most of the research in this field has been carried out in the English language, and there is little evidence on how these measures behave in other languages. This study focuses on identifying the best procedure for detecting RD in Spanish in older elementary students, comparing the validity, accuracy and goodness of fit of three different universal screening assessment approaches-the Psychometric Assessment Approach, the Curriculum-Based Assessment Approach and the Teacher Detection Approach-using RTI as a criterion to determine the goodness of fit of the different approaches. A total of 154 fifth-year primary students participated in this study. The results reveal that the multivariate inclusion of the evaluation approaches used is the best means of ensuring an efficient, valid assessment when attempting to identify RD among fifth graders. This finding has practical implications for the implementation of the RTI model in the field of RD.


Assuntos
Dislexia , Humanos , Idoso , Dislexia/diagnóstico , Leitura , Idioma , Estudantes , Currículo
20.
Pediatr Radiol ; 53(3): 523-543, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36348014

RESUMO

New tumor types are continuously being described with advances in molecular testing and genomic analysis resulting in better prognostics, new targeted therapy options and improved patient outcomes. As a result of these advances, pathological classification of tumors is periodically updated with new editions of the World Health Organization (WHO) Classification of Tumors books. In 2021, WHO Classification of Tumors of the Central Nervous System, 5th edition (CNS5), was published with major changes in pediatric brain tumors officially recognized including pediatric gliomas being separated from adult gliomas, ependymomas being categorized based on anatomical compartment and many new tumor types, most of them seen in children. Additional general changes, such as tumor grading now being done within tumor types rather than across entities and changes in definition of glioblastoma, are also relevant to pediatric neuro-oncology practice. The purpose of this manuscript is to highlight the major changes in pediatric brain tumors in CNS5 most relevant to radiologists. Additionally, brief descriptions of newly recognized entities will be presented with a focus on imaging findings.


Assuntos
Neoplasias Encefálicas , Neoplasias do Sistema Nervoso Central , Glioma , Adulto , Humanos , Criança , Neoplasias Encefálicas/patologia , Sistema Nervoso Central/patologia , Glioma/genética , Glioma/patologia , Organização Mundial da Saúde
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