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1.
Mol Cell ; 70(2): 358-370.e4, 2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29628308

RESUMO

To initiate V(D)J recombination for generating the adaptive immune response of vertebrates, RAG1/2 recombinase cleaves DNA at a pair of recombination signal sequences, the 12- and 23-RSS. We have determined crystal and cryo-EM structures of RAG1/2 with DNA in the pre-reaction and hairpin-forming complexes up to 2.75 Å resolution. Both protein and DNA exhibit structural plasticity and undergo dramatic conformational changes. Coding-flank DNAs extensively rotate, shift, and deform for nicking and hairpin formation. Two intertwined RAG1 subunits crisscross four times between the asymmetric pair of severely bent 12/23-RSS DNAs. Location-sensitive bending of 60° and 150° in 12- and 23-RSS spacers, respectively, must occur for RAG1/2 to capture the nonamers and pair the heptamers for symmetric double-strand breakage. DNA pairing is thus sequence-context dependent and structure specific, which partly explains the "beyond 12/23" restriction. Finally, catalysis in crystallo reveals the process of DNA hairpin formation and its stabilization by interleaved base stacking.


Assuntos
Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , Proteínas de Homeodomínio/metabolismo , Recombinação V(D)J , Sítios de Ligação , Catálise , Microscopia Crioeletrônica , Cristalografia por Raios X , DNA/genética , DNA/ultraestrutura , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/ultraestrutura , Células HEK293 , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/ultraestrutura , Humanos , Modelos Moleculares , Conformação de Ácido Nucleico , Ligação Proteica , Conformação Proteica , Relação Estrutura-Atividade
2.
Neuroimage ; 298: 120794, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39173693

RESUMO

Robust methods are needed for preclinical evaluation of novel Alzheimer Disease (AD) therapies to accelerate drug discovery. Quantitative Gradient Recalled Echo (qGRE) MRI has shown promise to provide insight into neurodegeneration in AD prior to atrophy development in humans, highlighting areas of low neuronal density. In this study a novel qGRE method (20 echoes, TE=2-40ms) is shown to non-invasively measure the longitudinal neuronal loss in the hippocampus of a mouse model of AD tauopathy Tg4510. Tg4510 (n=10) and wild type (WT, n=6) mice underwent MRI (7T field strength) at 3-7 months old. 3D qGRE approach was used to generate brain-specific R2* maps free of magnetic field inhomogeneity artifacts. Light-sheet microscopy of the brains stained with NeuN and MBP served to visualize neuronal nuclei and myelin content respectively. Significant decrease in NeuN staining between 3mo and 5mo was observed in the hippocampus of Tg4510, validating the mouse AD model. Longitudinal analysis showed clear decreases in R2* metric of qGRE signal in the Tg4510 mice hippocampus undergoing neurodegeneration between 3 and 5 months old. Histogram analysis revealed an upward trend in patterns of low R2* value (Dark Matter, DM), and broadening of R2* distribution. These were quantified as significant increase in both DM Volume Fraction (DMVF) and R2* Standard Deviation (SD) in Tg4510 mice (p=0.004/p=0.016 DMVF/SD) but not in WT controls (p>0.25). Further monotonical increase was also observed in both metrics in time. A significant negative correlation was observed between the DMVF and myelin content (p=0.01, r=-0.76), suggesting sensitivity of the technique to the loss of myelinated axons. The presented qGRE technique, validated by histological measurements, can be readily applied as in vivo tool in preclinical models of neurodegeneration for pharmacodynamics and mechanism of action assessment.


Assuntos
Doença de Alzheimer , Modelos Animais de Doenças , Imageamento por Ressonância Magnética , Camundongos Transgênicos , Animais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Camundongos , Imageamento por Ressonância Magnética/métodos , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Atrofia/patologia , Masculino , Feminino
3.
Curr Issues Mol Biol ; 46(5): 4251-4270, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38785527

RESUMO

Hepatocellular carcinoma (HCC) is a heterogeneous malignancy with complex carcinogenesis. Although there has been significant progress in the treatment of HCC over the past decades, drug resistance to chemotherapy remains a major obstacle in its successful management. In this study, we were able to reduce chemoresistance in cisplatin-resistant HepG2 cells by either silencing the expression of transglutaminase type 2 (TG2) using siRNA or by the pre-treatment of cells with the TG2 enzyme inhibitor cystamine. Further analysis revealed that, whereas the full-length TG2 isoform (TG2-L) was almost completely cytoplasmic in its distribution, the majority of the short TG2 isoform (TG2-S) was membrane-associated in both parental and chemoresistant HepG2 cells. Following the induction of cisplatin toxicity in non-chemoresistant parental cells, TG2-S, together with cisplatin, quickly relocated to the cytosolic fraction. Conversely, no cytosolic relocalisation of TG2-S or nuclear accumulation cisplatin was observed, following the identical treatment of chemoresistant cells, where TG2-S remained predominantly membrane-associated. This suggests that the deficient subcellular relocalisation of TG2-S from membranous structures into the cytoplasm may limit the apoptic response to cisplatin toxicity in chemoresistant cells. Structural analysis of TG2 revealed the presence of binding motifs for interaction of TG2-S with the membrane scaffold protein LC3/LC3 homologue that could contribute to a novel mechanism of chemotherapeutic resistance in HepG2 cells.

4.
Kidney Int ; 105(5): 980-996, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38423182

RESUMO

Collapsing focal segmental glomerulosclerosis (FSGS), also known as collapsing glomerulopathy (CG), is the most aggressive variant of FSGS and is characterized by a rapid progression to kidney failure. Understanding CG pathogenesis represents a key step for the development of targeted therapies. Previous work implicated the telomerase protein component TERT in CG pathogenesis, as transgenic TERT expression in adult mice resulted in a CG resembling that seen in human primary CG and HIV-associated nephropathy (HIVAN). Here, we used the telomerase-induced mouse model of CG (i-TERTci mice) to identify mechanisms to inhibit CG pathogenesis. Inactivation of WIP1 phosphatase, a p53 target acting in a negative feedback loop, blocked disease initiation in i-TERTci mice. Repression of disease initiation upon WIP1 deficiency was associated with senescence enhancement and required transforming growth factor-ß functions. The efficacy of a pharmacologic treatment to reduce disease severity in both i-TERTci mice and in a mouse model of HIVAN (Tg26 mice) was then assessed. Pharmacologic inhibition of WIP1 enzymatic activity in either the telomerase mice with CG or in the Tg26 mice promoted partial remission of proteinuria and ameliorated kidney histopathologic features. Histological as well as high-throughput sequencing methods further showed that selective inhibition of WIP1 does not promote kidney fibrosis or inflammation. Thus, our findings suggest that targeting WIP1 may be an effective therapeutic strategy for patients with CG.


Assuntos
Nefropatia Associada a AIDS , Glomerulosclerose Segmentar e Focal , Insuficiência Renal , Telomerase , Adulto , Humanos , Camundongos , Animais , Glomerulosclerose Segmentar e Focal/patologia , Telomerase/uso terapêutico , Nefropatia Associada a AIDS/patologia , Proteinúria , Insuficiência Renal/complicações , Modelos Animais de Doenças
5.
Biochem Biophys Res Commun ; 717: 150044, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38718567

RESUMO

Pulpitis constitutes a significant challenge in clinical management due to its impact on peripheral nerve tissue and the persistence of chronic pain. Despite its clinical importance, the correlation between neuronal activity and the expression of voltage-gated sodium channel 1.7 (Nav1.7) in the trigeminal ganglion (TG) during pulpitis is less investigated. The aim of this study was to examine the relationship between experimentally induced pulpitis and Nav1.7 expression in the TG and to investigate the potential of selective Nav1.7 modulation to attenuate TG abnormal activity associated with pulpitis. Acute pulpitis was induced at the maxillary molar (M1) using allyl isothiocyanate (AITC). The mice were divided into three groups: control, pulpitis model, and pulpitis model treated with ProTx-II, a selective Nav1.7 channel inhibitor. After three days following the surgery, we conducted a recording and comparative analysis of the neural activity of the TG utilizing in vivo optical imaging. Then immunohistochemistry and Western blot were performed to assess changes in the expression levels of extracellular signal-regulated kinase (ERK), c-Fos, collapsin response mediator protein-2 (CRMP2), and Nav1.7 channels. The optical imaging result showed significant neurological excitation in pulpitis TGs. Nav1.7 expressions exhibited upregulation, accompanied by signaling molecular changes suggestive of inflammation and neuroplasticity. In addition, inhibition of Nav1.7 led to reduced neural activity and subsequent decreases in ERK, c-Fos, and CRMP2 levels. These findings suggest the potential for targeting overexpressed Nav1.7 channels to alleviate pain associated with pulpitis, providing practical pain management strategies.


Assuntos
Canal de Sódio Disparado por Voltagem NAV1.7 , Pulpite , Animais , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.7/genética , Camundongos , Masculino , Pulpite/metabolismo , Pulpite/patologia , Gânglio Trigeminal/metabolismo , Neurônios/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia , Modelos Animais de Doenças , Peptídeos e Proteínas de Sinalização Intercelular
6.
Cancer Immunol Immunother ; 73(2): 22, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279992

RESUMO

Mouse tumour models are extensively used as a pre-clinical research tool in the field of oncology, playing an important role in anticancer drugs discovery. Accordingly, in cancer genomics research, the demand for next-generation sequencing (NGS) is increasing, and consequently, the need for data analysis pipelines is likewise growing. Most NGS data analysis solutions to date do not support mouse data or require highly specific configuration for their use. Here, we present a genome analysis pipeline for mouse tumour NGS data including the whole-genome sequence (WGS) data analysis flow for somatic variant discovery, and the RNA-seq data flow for differential expression, functional analysis and neoantigen prediction. The pipeline is based on standards and best practices and integrates mouse genome references and annotations. In a recent study, the pipeline was applied to demonstrate the efficacy of low dose 6-thioguanine (6TG) treatment on low-mutation melanoma in a pre-clinical mouse model. Here, we further this study and describe in detail the pipeline and the results obtained in terms of tumour mutational burden (TMB) and number of predicted neoantigens, and correlate these with 6TG effects on tumour volume. Our pipeline was expanded to include a neoantigen analysis, resulting in neopeptide prediction and MHC class I antigen presentation evaluation. We observed that the number of predicted neoepitopes were more accurate indicators of tumour immune control than TMB. In conclusion, this study demonstrates the usability of the proposed pipeline, and suggests it could be an essential robust genome analysis platform for future mouse genomic analysis.


Assuntos
Melanoma , Tioguanina , Animais , Camundongos , Tioguanina/farmacologia , Genômica/métodos , Mutação , RNA-Seq
7.
BMC Med ; 22(1): 209, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38807146

RESUMO

BACKGROUND: TG103, a glucagon-like peptide-1 analog, is being investigated as an option for weight management. We aimed to determine the safety, tolerability, pharmacokinetics, and pharmacodynamics of TG103 injection in participants who are overweight or obese without diabetes. METHODS: In this randomized, double-blind, placebo-controlled, multiple-dose phase 1b study, participants aged 18-75 years with a body-mass index (BMI) ≥ 26.0 kg/m2 and body weight ≥ 60 kg were enrolled from three centers in China. The study included three cohorts, and in each cohort, eligible participants were randomly assigned (3:1) to one of three once-weekly subcutaneous TG103 groups (15.0, 22.5 and 30.0 mg) or matched placebo, without lifestyle interventions. In each cohort, the doses of TG103 were escalated in 1-week intervals to the desired dose over 1 to 4 weeks. Then participants were treated at the target dose until week 12 and then followed up for 2 weeks. The primary endpoint was safety and tolerability assessed by the incidence and severity of adverse events (AEs) from baseline to the end of the follow-up period. Secondary endpoints included pharmacokinetic and pharmacodynamic profiles of TG103 and the occurrence of anti-drug antibodies to TG103. RESULTS: A total of 147 participants were screened, and 48 participants were randomly assigned to TG103 (15.0, 22.5 and 30.0 mg groups, n = 12 per group) or placebo (n = 12). The mean (standard deviation, SD) age of the participants was 33.9 (10.0) years; the mean bodyweight was 81.65 (10.50) kg, and the mean BMI was 29.8 (2.5) kg/m2. A total of 466 AEs occurred in 45 of the 48 participants, with 35 (97.2%) in the TG103 group and 10 (83.3%) in the pooled placebo group. Most AEs were grade 1 or 2 in severity, and there were no serious adverse events (SAEs), AEs leading to death, or AEs leading to discontinuation of treatment. The steady-state exposure of TG103 increased with increasing dose and was proportional to Cmax,ss, AUCss, AUC0-t and AUC0-inf. The mean values of Cmax,ss ranged from 951 to 1690 ng/mL, AUC0-t ranged from 150 to 321 µg*h/mL, and AUC0-inf ranged from 159 to 340 µg*h/mL. TG103 had a half-life of 110-116 h, with a median Tmax of 36-48 h. After treatment for 12 weeks, the mean (SD) values of weight loss from baseline in the TG103 15.0 mg, 22.5 mg and 30.0 mg groups were 5.65 (3.30) kg, 5.35 (3.39) kg and 5.13 (2.56) kg, respectively, and that in the placebo group was 1.37 (2.13) kg. The least square mean percent weight loss from baseline to D85 in all the TG103 groups was more than 5% with p < 0.05 for all comparisons with placebo. CONCLUSIONS: In this trial, all three doses of once-weekly TG103 were well tolerated with an acceptable safety profile. TG103 demonstrated preliminary 12-week body weight loss without lifestyle interventions, thus showing great potential for the treatment of overweight and obesity. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04855292. Registered on April 22, 2021.


Assuntos
Obesidade , Sobrepeso , Humanos , Pessoa de Meia-Idade , Masculino , Adulto , Feminino , Método Duplo-Cego , Obesidade/tratamento farmacológico , Sobrepeso/tratamento farmacológico , Idoso , Adulto Jovem , Adolescente , China , Placebos/administração & dosagem , Injeções Subcutâneas , Peptídeo 1 Semelhante ao Glucagon
8.
J Med Virol ; 96(4): e29586, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38587173

RESUMO

Inappropriate sinus tachycardia (IST) is one of the manifestations of the post-COVID-19 syndrome (PCS), which pathogenesis remains largely unknown. This study aimed to identify potential risk factors for IST in individuals with PCS. The 1349 patients with PCS were included into the study. Clinical examination, 24H Holter ECG, 24H ambulatory blood pressure monitoring and biochemical tests were performed 12-16 weeks after the COVID-19 in all participants. IST was found in 69 (3.5%) individuals. In the clinical assessment IST patients were characterized by a higher age (p < 0.001) and lower prevalence of the diagnosed hypertension (p = 0.012), compared to remaining patients. Biochemical testing showed higher serum triglycerides (1.66 vs. 1.31 pmol/L, p = 0.007) and higher prevalence of a low high-density lipoprotein (HDL) cholesterol (24.6% vs. 15.2%, p = 0.035) in the IST group. Subsequently, the triglicerydes (TG)/HDL ratio, an indicator of insulin resistance, was significantly higher in the IST individuals (3.2 vs. 2.4, p = 0.005). 24H monitoring revealed a significantly higher minimum diastolic, maximum systolic and mean arterial blood pressure values in the IST group (p < 0.001 for all), suggesting a high prevalence of undiagnosed hypertension. A multivariate analysis confirmed the predictive value TG/HDL ratio >3 (OR 2.67, p < 0.001) as predictors of IST development. A receiver operating characteristic curve analysis of the relationship between the TG/HDL ratio and the IST risk showed that the predictive cut-off point for this parameter was 2.46 (area under the ROC curve = 0.600, p = 0.004). Based on these findings, one can conclude that insulin resistance seems to be a risk factor of IST, a common component of PCS.


Assuntos
COVID-19 , Hipertensão , Resistência à Insulina , Humanos , Estudos Retrospectivos , Taquicardia Sinusal/diagnóstico , Lipoproteínas HDL , Monitorização Ambulatorial da Pressão Arterial , Síndrome de COVID-19 Pós-Aguda , Triglicerídeos , HDL-Colesterol , Fatores de Risco , Hipertensão/complicações , Hipertensão/epidemiologia
9.
Crit Rev Toxicol ; 54(7): 476-484, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39041360

RESUMO

The European Union (EU) Chemicals Strategy for Sustainability regards chemicals that affect the immune system among the most harmful ones. The Extended One-Generation Reproductive Toxicity study (EOGRTS; Organisation for Economic Co-Operation and Development (OECD) Test Guideline (TG) 443), addresses, among others, potential effects of chemicals on development. In specific cases, the EOGRTS is performed with addition of a so-called cohort 3, that addresses potential effects on the developing immune system, by means of a central assay measuring the T-cell dependent antibody response (TDAR). This assay is based on an interplay of antigen presentation, T-cell help and antibody production by B-cells, and together comprises a functional immune response. In the context of the EOGRTS review project of the European Chemicals Agency (ECHA), we evaluated 15 available TDARs for compliance with conduct and reporting requirements. Collectively, the majority of the TDAR studies were considered to be adequately conducted. We however observed: (i) the protocols differed by the antigen used (sheep red blood cells (SRBC) or KLH), the route of administration (intravenous, intraperitoneal, or subcutaneous), prime or prime/boost immunizations, and whether IgG was measured. (ii) There was major variation in the effects of the positive control for immunosuppression, cyclophosphamide. (iii) Proficiency was not always shown. (iv) Statistical analysis was not always done or reported. (v) Results of effects on lymphocyte populations or other immunotoxicity observations obtained in cohort 1 (or 2) of the EOGRTS were not always discussed together with results of the TDAR. Taken together, next to an improved quality of reporting, this may suggest a need to better define the conduct of the TDAR in OECD TG 443 and OECD Guidance Document (GD) 151, at least for certain aspects.


Assuntos
União Europeia , Reprodução , Linfócitos T , Testes de Toxicidade , Animais , Testes de Toxicidade/métodos , Linfócitos T/imunologia , Linfócitos T/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Formação de Anticorpos/efeitos dos fármacos , Humanos
10.
Neurochem Res ; 49(8): 1993-2004, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38782837

RESUMO

Phosphodiesterase 8 (PDE8), as a member of PDE superfamily, specifically promotes the hydrolysis and degradation of intracellular cyclic adenosine monophosphate (cAMP), which may be associated with pathogenesis of Alzheimer's disease (AD). However, little is currently known about potential role in the central nervous system (CNS). Here we investigated the distribution and expression of PDE8 in brain of mouse, which we believe can provide evidence for studying the role of PDE8 in CNS and the relationship between PDE8 and AD. Here, C57BL/6J mice were used to observe the distribution patterns of two subtypes of PDE8, PDE8A and PDE8B, in different sexes in vivo by western blot (WB). Meanwhile, C57BL/6J mice were also used to demonstrate the distribution pattern of PDE8 in selected brain regions and localization in neural cells by WB and multiplex immunofluorescence staining. Furthermore, the triple transgenic (3×Tg-AD) mice and wild type (WT) mice of different ages were used to investigate the changes of PDE8 expression in the hippocampus and cerebral cortex during the progression of AD. PDE8 was found to be widely expressed in multiple tissues and organs including heart, kidney, stomach, brain, and liver, spleen, intestines, and uterus, with differences in expression levels between the two subtypes of PDE8A and PDE8B, as well as two sexes. Meanwhile, PDE8 was widely distributed in the brain, especially in areas closely related to cognitive function such as cerebellum, striatum, amygdala, cerebral cortex, and hippocampus, without differences between sexes. Furthermore, PDE8A was found to be expressed in neuronal cells, microglia and astrocytes, while PDE8B is only expressed in neuronal cells and microglia. PDE8A expression in the hippocampus of both female and male 3×Tg-AD mice was gradually increased with ages and PDE8B expression was upregulated only in cerebral cortex of female 3×Tg-AD mice with ages. However, the expression of PDE8A and PDE8B was apparently increased in both cerebral cortex and hippocampus in both female and male 10-month-old 3×Tg-AD mice compared WT mice. These results suggest that PDE8 may be associated with the progression of AD and is a potential target for its prevention and treatment in the future.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases , Doença de Alzheimer , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Animais , Feminino , Masculino , Camundongos , 3',5'-AMP Cíclico Fosfodiesterases/metabolismo , 3',5'-AMP Cíclico Fosfodiesterases/genética , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Hipocampo/metabolismo
11.
J Inherit Metab Dis ; 47(4): 731-745, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38356271

RESUMO

Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is the most prevalent mitochondrial fatty acid ß-oxidation disorder. In this study, we assessed the variability of the lipid profile in MCADD by analysing plasma samples obtained from 25 children with metabolically controlled MCADD (following a normal diet with frequent feeding and under l-carnitine supplementation) and 21 paediatric control subjects (CT). Gas chromatography-mass spectrometry was employed for the analysis of esterified fatty acids, while high-resolution C18-liquid chromatography-mass spectrometry was used to analyse lipid species. We identified a total of 251 lipid species belonging to 15 distinct lipid classes. Principal component analysis revealed a clear distinction between the MCADD and CT groups. Univariate analysis demonstrated that 126 lipid species exhibited significant differences between the two groups. The lipid species that displayed the most pronounced variations included triacylglycerols and phosphatidylcholines containing saturated and monounsaturated fatty acids, specifically C14:0 and C16:0, which were found to be more abundant in MCADD. The observed changes in the plasma lipidome of children with non-decompensated MCADD suggest an underlying alteration in lipid metabolism. Therefore, longitudinal monitoring and further in-depth investigations are warranted to better understand whether such alterations are specific to MCADD children and their potential long-term impacts.


Assuntos
Acil-CoA Desidrogenase , Erros Inatos do Metabolismo Lipídico , Lipidômica , Fosfolipídeos , Triglicerídeos , Humanos , Erros Inatos do Metabolismo Lipídico/sangue , Lipidômica/métodos , Criança , Masculino , Feminino , Triglicerídeos/sangue , Fosfolipídeos/sangue , Pré-Escolar , Acil-CoA Desidrogenase/deficiência , Lactente , Adolescente , Metabolismo dos Lipídeos , Estudos de Casos e Controles , Ácidos Graxos/sangue , Ácidos Graxos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Carnitina/sangue
12.
Cell Biol Toxicol ; 40(1): 69, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136868

RESUMO

Many persistent organic pollutants (POPs) are suspected endocrine disruptors and it is important to investigate their effects at low concentrations relevant to human exposure. Here, the OECD test guideline #456 steroidogenesis assay was downscaled to a 96-well microplate format to screen 24 POPs for their effects on viability, and testosterone and estradiol synthesis using the human adrenocortical cell line H295R. The compounds (six polyfluoroalkyl substances, five organochlorine pesticides, ten polychlorinated biphenyls and three polybrominated diphenyl ethers) were tested at human-relevant levels (1 nM to 10 µM). Increased estradiol synthesis, above the OECD guideline threshold of 1.5-fold solvent control, was shown after exposure to 10 µM PCB-156 (153%) and PCB-180 (196%). Interestingly, the base hormone synthesis varied depending on the cell batch. An alternative data analysis using a linear mixed-effects model that include multiple independent experiments and considers batch-dependent variation was therefore applied. This approach revealed small but statistically significant effects on estradiol or testosterone synthesis for 17 compounds. Increased testosterone levels were demonstrated even at 1 nM for PCB-74 (18%), PCB-99 (29%), PCB-118 (16%), PCB-138 (19%), PCB-180 (22%), and PBDE-153 (21%). The MTT assay revealed significant effects on cell viability after exposure to 1 nM of perfluoroundecanoic acid (12%), 3 nM PBDE-153 (9%), and 10 µM of PCB-156 (6%). This shows that some POPs can interfere with endocrine signaling at concentrations found in human blood, highlighting the need for further investigation into the toxicological mechanisms of POPs and their mixtures at low concentrations relevant to human exposure.


Assuntos
Sobrevivência Celular , Disruptores Endócrinos , Poluentes Orgânicos Persistentes , Bifenilos Policlorados , Testosterona , Humanos , Testosterona/biossíntese , Testosterona/metabolismo , Poluentes Orgânicos Persistentes/metabolismo , Disruptores Endócrinos/toxicidade , Disruptores Endócrinos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Bifenilos Policlorados/toxicidade , Éteres Difenil Halogenados/toxicidade , Estradiol/metabolismo , Estrogênios , Linhagem Celular , Praguicidas/toxicidade , Hidrocarbonetos Clorados/toxicidade
13.
BMC Gastroenterol ; 24(1): 322, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304833

RESUMO

BACKGROUND: Acute suppurative cholangitis (ASC) lacks sensitive and specific preoperative diagnostic criteria. Some researchers suggest treating ASC as severe cholangitis. This study aimed to explore the relationship between the Tokyo Guidelines 2018 (TG18) grading system for acute cholangitis (AC) and the diagnosis of acute suppurative cholangitis (ASC), searching for independent risk factors of ASC and develop a nomogram to discriminate ASC from acute nonsuppurative cholangitis (ANSC) accurately. METHODS: After applying the inclusion and exclusion criteria, 401 patients with acute cholangitis (AC) were retrospectively analyzed at Nanjing First Hospital between January 2015 and June 2023. SPSS version 27.0 and R studio software were used to analyze data obtained from medical records. The results were validated in a prospective cohort of 82 AC patients diagnosed at Nanjing First Hospital between July 2023 and February 2024. RESULTS: Among the 401 patients, 102 had suppurative bile (the ASC group; AC grade I: 40 [39.2%], AC grade II: 27 [26.5%], AC grade III: 35 [34.3%]), whereas 299 did not have (the ANSC group; AC grade I: 157 [52.5%], AC grade II: 92 [30.8%], AC grade III: 50 [16.7%]). The specificity of ASC for diagnosing moderate-to-severe cholangitis is 79.7%. Multivariate logistic regression analysis identified concurrent cholecystitis, CRP, PCT, TBA, and bile duct diameter as independent risk factors for suppurative bile, and all of these factors were included in the nomogram. The calibration curve exhibited consistency between the nomogram and the actual observation, and the area under the curve was 0.875 (95% confidence interval: 0.835-0.915), sensitivity was 86.6%, and specificity was 75.5%. CONCLUSION: Suppurative bile is a specific indicator for diagnosing moderate-to-severe cholangitis. However, diagnosing ASC with AC grade II and AC grade III has the risk of missed diagnosis as the sensitivity is only 60.8%. To improve the diagnostic rate of ASC, this study identified concurrent cholecystitis, CRP, PCT, TBA, and preoperative bile duct diameter as independent risk factors for ASC, and a nomogram was developed to help physicians recognize patients with ASC.


Assuntos
Colangite , Nomogramas , Humanos , Colangite/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Estudos de Casos e Controles , Fatores de Risco , Doença Aguda , Idoso , Estudos Retrospectivos , Supuração , Estudos Prospectivos , Adulto , Índice de Gravidade de Doença , Sensibilidade e Especificidade , Diagnóstico Diferencial
14.
BMC Infect Dis ; 24(1): 53, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38183002

RESUMO

BACKGROUND: Understanding the burden of dyslipidemia and its associated factors among adult people living with HIV on dolutegravir (DTG) based anti-retroviral therapy (ART) is critical to provide clinical guidance and risk reduction strategies in our setting. METHODS: We conducted a cross-sectional study on adult people living with HIV on DTG based ART between July and August 2022 at Mengo Hospital, a private not for profit missionary hospital owned by the Church of Uganda. Dyslipidemia was defined as: Total cholesterol (TC) ≥ 5.2 mmol/l, or high-density lipoprotein (HDL) < 1 mmol/l for men and < 1.3 mmol/l for women, or triglycerides (TG) ≥ 1.7 mmol/l, and low-density lipoprotein (LDL) ≥ 3.4 mmol/l. A participant was considered to have dyslipidemia if they had any of the lipid profile parameters in the above ranges. Socio-demographic information, clinical data and behavioral characteristics were collected. Fasting lipid profile and fasting blood glucose levels were also measured. Bivariate and multivariate analyses were done using a generalized linear model regression of the Poisson family with a log link (modified Poisson) using robust standard errors since the prevalence of dyslipidemia was more than 10%. Adjusted prevalence ratios (PR) were reported with their 95% confidence intervals (CI). A p-value of less than 0.05 was considered statistically significant. RESULTS: A total of 341 participants were included. The prevalence of dyslipidemia was 78.0%, (95%CI:73.3-82.1). The highest prevalence was for low HDL (72.1%, 95%CI 67.1-76.7) followed by high TG (20.2%, 95%CI: 16.3-24.9), high TC (12.0%, 95%CI: 9.0-15.9) and high LDL (6.5%, 95%CI: 4.3-9.6). Female sex (aPR:1.55, 95%CI: 1.32-1.84, p < 0.001) and previous use of protease inhibitor (PI) based ART regimen (aPR:1.26, 95%CI: 1.04-1.53, p = 0.018) were significantly associated with dyslipidemia. CONCLUSION: We demonstrate that the prevalence of dyslipidemia is very high as it was present in more than three quarters of the study participants. Female sex and previous use of PI based ART regimen were significantly associated with dyslipidemia. Management of dyslipidemia should be integrated in the HIV treatment package and we recommend further inquiry into the temporal relationship between dyslipidemia and DTG among ART patients, if any.


Assuntos
Dislipidemias , Adulto , Masculino , Humanos , Feminino , Centros de Atenção Terciária , Uganda/epidemiologia , Estudos Transversais , Dislipidemias/epidemiologia , Lipoproteínas LDL
15.
J Periodontal Res ; 59(3): 512-520, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38243688

RESUMO

BACKGROUND: Periodontitis is a chronic inflammatory disease defined by the pathologic loss of the periodontal ligament and alveolar bone in relation to aging. Although clinical cohort studies reported that periodontitis is significantly elevated in males compared to females, emerging evidence indicates that females with dementia are at a greater risk for periodontitis and decreased alveolar bone. OBJECTIVE: This study aimed to evaluate whether dementia is a potential sex-dependent risk factor for periodontal bone loss using an experimental model of periodontitis induced in the triple transgenic (3x-Tg) dementia-like mice and clinical samples collected from senior 65 plus age patients with diagnosed dementia. MATERIALS AND METHODS: We induced periodontitis in dementia-like triple-transgenic (3x-Tg) male and female mice and age-matched wild-type (WT) control mice by ligature placement. Then, alveolar bone loss and osteoclast activity were evaluated using micro-CT and in situ imaging assays. In addition, we performed dental examinations on patients with diagnosed dementia. Finally, dementia-associated Aß42 and p-Tau (T181) and osteoclastogenic receptor activator of nuclear factor kappa-Β ligand (RANKL) in gingival crevicular fluid (GCF) collected from mice and clinical samples were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Alveolar bone loss and in situ osteoclast activity were significantly elevated in periodontal lesions of 3x-Tg females but not males, compared to wild-type control mice. In addition, we also observed that the probing pocket depth (PPD) was also significantly elevated in female patients with dementia. Using ELISA assay, we observed that females had elevated levels of osteoclastogenic RANKL and dementia-associated Aß42 and p-Tau (T181) in the GCF collected from experimental periodontitis lesions and clinical samples. CONCLUSION: Altogether, we demonstrate that females with dementia have an increased risk for periodontal bone loss compared to males.


Assuntos
Perda do Osso Alveolar , Demência , Modelos Animais de Doenças , Camundongos Transgênicos , Periodontite , Ligante RANK , Animais , Feminino , Perda do Osso Alveolar/patologia , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/metabolismo , Masculino , Camundongos , Demência/etiologia , Humanos , Idoso , Ligante RANK/análise , Ligante RANK/metabolismo , Fatores Sexuais , Periodontite/complicações , Periodontite/patologia , Microtomografia por Raio-X , Osteoclastos/patologia , Peptídeos beta-Amiloides/metabolismo , Líquido do Sulco Gengival/química , Fragmentos de Peptídeos/análise , Fatores de Risco
16.
Biometals ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38811521

RESUMO

2-((1-(4-((2,4,6-trioxohexahydropyrimidin-5-yl)diazenyl) phenyl) ethylidene) amino) benzoic acid (H3L), and its V(IV), Co(II), Ni(II), Cu(II), Pd(II) and Ag(I) chelates were synthesized. They were defined using multiple spectral and analytical techniques. With the exception of Ag(I) chelate, all chelates possessed non-electrolytic character. Square pyramidal shape was proposed for V(IV) chelate and Square planar for the other chelates. The analysis of functional group bands of H3L and its coordination compounds alludes that H3L chelated as neutral tetradentate via nitrogen atoms of azo and azomethine groups, oxygen atom of carbonyl of barbituric acid and OH of the carboxylic group. TG/DTG predicted the thermal behaviors of all compounds. The antibacterial activity of H3L and its coordination compounds was conducted against Proteus mirabilis at concentrations of 250, 500, and 1000 µg/mL. Ag(I) at 1000 µg/mL, showed the most inhibiting potency against P. mirabilis and registered zone of inhibition of 28.33 ± 0.84 mm and highest biofilm inhibition of 70.31%. At 50 Gy of gamma irradiation, the reducing effect of Ag(I) chelate was improved. The protein interruption of P. mirabilis was greatly interrupted by increasing the concentration of the chaletes. Also, Ag(I) showed the highest cytotoxicity with IC50 value of 11.5 µg/ mL. The novelty of this study is the synthesis of a new azo-Schiff base and this is almost the first publication of the effect of azo-Schiff ligands against that bacterial strain P. mirabilis.

17.
Bioorg Chem ; 151: 107597, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39002511

RESUMO

The efficacy of conventional chemotherapies in treating clear cell renal cell carcinoma (ccRCC) is often limited due to its high molecular diversity, generally low response rates to standard treatments, and prevalent drug resistance. Recent advancements in the molecular understanding of ccRCC, alongside the discovery of novel therapeutic agents targeting specific proteins, have significantly altered the treatment landscape for ccRCC. Here, we synthesized 27 new compounds that are derivatives of TG-101209 to modulate BUB1B (BUB1 mitotic checkpoint serine/threonine kinase B). BUB1B has been recently identified as a drug target for the development of effective ccRCC treatment based on global transcriptomics profiling of ccRCC tumours and gene co-expression network analysis. We characterized the molecular structures of these 27 compounds by 1H and 13C NMR and Mass spectrometry. We evaluated the effect of these 27 compounds by analysing the modulation of the BUB1B expression. Our primary objective was to design and assess the efficacy of these new compounds in reducing the viability of Caki-1 cells, a ccRCC cell line. We performed the computational docking studies by the Schrödinger Maestro software and demonstrated that three of these compounds (13a, 5i, and 5j) effectively downregulated BUB1B expression and eventually triggered necrosis and apoptosis in the Caki-1 cell line based on the structure-activity relationship (SAR) analysis. The IC50 values for compounds 13a, 5i, and 5j were calculated as 2.047 µM, 10.046 µM, and 6.985 µM, respectively, indicating their potent inhibitory effects on cell viability. Our study suggests that these compounds targeting BUB1B could offer a more effective and promising approach for ccRCC treatment compared to the conventionally used tyrosine kinase inhibitors. Our study underscores the potential of leveraging targeted therapies against specific molecular pathways in ccRCC may open new avenues for the development of effective treatment strategies against ccRCC.


Assuntos
Antineoplásicos , Carcinoma de Células Renais , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias Renais , Inibidores de Proteínas Quinases , Proteínas Serina-Treonina Quinases , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/metabolismo , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Relação Estrutura-Atividade , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Estrutura Molecular , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/síntese química , Relação Dose-Resposta a Droga , Proliferação de Células/efeitos dos fármacos , Simulação de Acoplamento Molecular , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Proteínas de Ciclo Celular
18.
Acta Pharmacol Sin ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152295

RESUMO

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder characterized by cognitive impairments. Despite the limited efficacy of current treatments for AD, the 1,2,4-oxadiazole structure has garnered significant attention in medicinal chemistry due to its potential impact on mGluR1 and its association with AD therapy. In this study, a series of novel 1,2,4-oxadiazole derivatives were designed, synthesized, and evaluated for the neuroprotective effects in human neuroblastoma (SH-SY5Y) cells. Among all the derivatives tested, FO-4-15 (5f) existed the lowest cytotoxicity and the highest protective effect against H2O2. Based on these in vitro results, FO-4-15 was administered to 3×Tg mice and significantly improved the cognitive impairments of the AD mice. Pathological analysis showed that FO-4-15 significantly reduced Aß accumulation, Tau hyper-phosphorylation, and synaptic impairments in the 3×Tg mice. Dysfunction of the CaMKIIα/Fos signaling pathway in 3×Tg mice was found to be restored by FO-4-15 and the necessity of the CaMKIIα/Fos for FO-4-15 was subsequently confirmed by the use of a CaMKIIα inhibitor in vitro. Beyond that, mGluR1 was identified to be a potential target of FO-4-15, and the interaction of FO-4-15 and mGluR1 was displayed by Ca2+ flow increase, molecular docking, and interaction energy analysis. The target of FO-4-15 was further confirmed in vitro by JNJ16259685, a nonselective inhibitor of mGluR1. These findings suggest that FO-4-15 may hold promise as a potential treatment for Alzheimer's disease.

19.
Environ Res ; 259: 119513, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38950815

RESUMO

To investigate the effect of stalk type on the metallization degrees in FeCl3-derived magnetic biochar (MBC), MBC was synthesized via an impregnation-pyrolysis method using six different stalks. The Fe0 content in MBC significantly influenced its magnetic properties and ostensibly governed its catalytic capabilities. Analysis of the interaction between stalks and FeCl3 revealed that the variation in metallization degrees, resulting from FeCl2 decomposition (6.1%) and stalk-mediated reduction (20.7%), was directly responsible for the observed differences in MBC metallization. The presence of oxygen-containing functional groups and fixed carbon appeared to promote metallization in MBC induced by reduction. A series of statistical analyses indicated that the cellulose, lignin, and hemicellulose content of the stalks were key factors contributing to differences in MBC metallization degrees. Further exploration revealed that hemicellulose and cellulose were more effective than lignin in enhancing metallization through FeCl2 decomposition and reduction. Constructing stalk models demonstrated that the variance in the content of these three biomass components across the six stalk types could lead to differences in the metallization degree attributable to reduction and FeCl2 decomposition, thereby affecting the overall metallization degree of MBC. A prediction model for MBC metallization degree was developed based on these findings. Moreover, the elevated Si content in some stalks facilitated the formation of Fe2(SiO4), which subsequently impeded the reduction process. This study provides a theoretical foundation for the informed selection of stalk feedstocks in the production of FeCl3-derived MBC.


Assuntos
Carvão Vegetal , Cloretos , Compostos Férricos , Pirólise , Carvão Vegetal/química , Compostos Férricos/química , Cloretos/química , Lignina/química , Celulose/química , Polissacarídeos
20.
Environ Res ; 256: 119180, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38795948

RESUMO

The main focus of anticancer drug discovery is on developing medications that are gentle on normal cells and should have the ability to target multiple anti-cancer pathways. Liver cancer is becoming a worldwide epidemic due to the highest occurring and reoccurring rate in some countries. Calotropis procera is a xerophytic herbal plant growing wildly in Saudi Arabia. Due to its anti-angiogenic and anticancer capabilities, "C. procera" is a viable option for developing innovative anticancer medicines. However, no study has been done previously, to discover angiogenic and anti-cancer targets which are regulated by C. procera in liver cancer. In this study, leaves, stems, flowers, and seeds of C. procera were used to prepare crude extracts and were fractionated into four solvents of diverse polarities. These bioactivity-guided solvent fractions helped to identify useful compounds with minimal side effects. The phytoconstituents present in the leaves and stem were identified by GC-MS. In silico studies were done to predict the anti-cancer targets by major bioactive constituents present in leaves and stem extracts. A human angiogenesis antibody array was performed to profile novel angiogenic targets. The results from this study showed that C. procera extracts are an ideal anti-cancer remedy with minimum toxicity to normal cells as revealed by zebrafish in vivo toxicity screening assays. The novel antiangiogenic and anticancer targets identified in this study could be explored to design medication against liver cancer.


Assuntos
Calotropis , Neoplasias Hepáticas , Extratos Vegetais , Peixe-Zebra , Calotropis/química , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Neoplasias Hepáticas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Neoplasias da Mama/tratamento farmacológico , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Folhas de Planta/química , Feminino , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/química , Simulação por Computador , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/análise , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/análise
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