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1.
Cell ; 166(4): 867-880, 2016 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-27518562

RESUMO

We report that astrocytic insulin signaling co-regulates hypothalamic glucose sensing and systemic glucose metabolism. Postnatal ablation of insulin receptors (IRs) in glial fibrillary acidic protein (GFAP)-expressing cells affects hypothalamic astrocyte morphology, mitochondrial function, and circuit connectivity. Accordingly, astrocytic IR ablation reduces glucose-induced activation of hypothalamic pro-opio-melanocortin (POMC) neurons and impairs physiological responses to changes in glucose availability. Hypothalamus-specific knockout of astrocytic IRs, as well as postnatal ablation by targeting glutamate aspartate transporter (GLAST)-expressing cells, replicates such alterations. A normal response to altering directly CNS glucose levels in mice lacking astrocytic IRs indicates a role in glucose transport across the blood-brain barrier (BBB). This was confirmed in vivo in GFAP-IR KO mice by using positron emission tomography and glucose monitoring in cerebral spinal fluid. We conclude that insulin signaling in hypothalamic astrocytes co-controls CNS glucose sensing and systemic glucose metabolism via regulation of glucose uptake across the BBB.


Assuntos
Astrócitos/metabolismo , Glucose/metabolismo , Hipotálamo/metabolismo , Insulina/metabolismo , Transdução de Sinais , Sistema X-AG de Transporte de Aminoácidos/genética , Sistema X-AG de Transporte de Aminoácidos/metabolismo , Animais , Barreira Hematoencefálica , Retículo Endoplasmático/metabolismo , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Homeostase , Camundongos , Mitocôndrias/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Pró-Opiomelanocortina/metabolismo , Receptor de Insulina/genética , Receptor de Insulina/metabolismo
2.
Plant Cell ; 35(9): 3280-3302, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37378595

RESUMO

Protein activities depend heavily on protein complex formation and dynamic posttranslational modifications, such as phosphorylation. The dynamic nature of protein complex formation and posttranslational modifications is notoriously difficult to monitor in planta at cellular resolution, often requiring extensive optimization. Here, we generated and exploited the SYnthetic Multivalency in PLants (SYMPL)-vector set to assay protein-protein interactions (PPIs) (separation of phases-based protein interaction reporter) and kinase activities (separation of phases-based activity reporter of kinase) in planta, based on phase separation. This technology enabled easy detection of inducible, binary and ternary PPIs among cytoplasmic and nuclear proteins in plant cells via a robust image-based readout. Moreover, we applied the SYMPL toolbox to develop an in vivo reporter for SNF1-related kinase 1 activity, allowing us to visualize tissue-specific, dynamic SnRK1 activity in stable transgenic Arabidopsis (Arabidopsis thaliana) plants. The SYMPL cloning toolbox provides a means to explore PPIs, phosphorylation, and other posttranslational modifications with unprecedented ease and sensitivity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fosforilação , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Processamento de Proteína Pós-Traducional , Plantas Geneticamente Modificadas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo
3.
Nature ; 574(7780): 712-716, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31597163

RESUMO

Cancers are caused by genomic alterations known as drivers. Hundreds of drivers in coding genes are known but, to date, only a handful of noncoding drivers have been discovered-despite intensive searching1,2. Attention has recently shifted to the role of altered RNA splicing in cancer; driver mutations that lead to transcriptome-wide aberrant splicing have been identified in multiple types of cancer, although these mutations have only been found in protein-coding splicing factors such as splicing factor 3b subunit 1 (SF3B1)3-6. By contrast, cancer-related alterations in the noncoding component of the spliceosome-a series of small nuclear RNAs (snRNAs)-have barely been studied, owing to the combined challenges of characterizing noncoding cancer drivers and the repetitive nature of snRNA genes1,7,8. Here we report a highly recurrent A>C somatic mutation at the third base of U1 snRNA in several types of tumour. The primary function of U1 snRNA is to recognize the 5' splice site via base-pairing. This mutation changes the preferential A-U base-pairing between U1 snRNA and the 5' splice site to C-G base-pairing, and thus creates novel splice junctions and alters the splicing pattern of multiple genes-including known drivers of cancer. Clinically, the A>C mutation is associated with heavy alcohol use in patients with hepatocellular carcinoma, and with the aggressive subtype of chronic lymphocytic leukaemia with unmutated immunoglobulin heavy-chain variable regions. The mutation in U1 snRNA also independently confers an adverse prognosis to patients with chronic lymphocytic leukaemia. Our study demonstrates a noncoding driver in spliceosomal RNAs, reveals a mechanism of aberrant splicing in cancer and may represent a new target for treatment. Our findings also suggest that driver discovery should be extended to a wider range of genomic regions.


Assuntos
Mutação , Neoplasias/genética , RNA Nuclear Pequeno/genética , Spliceossomos/genética , Humanos , Neoplasias/patologia , Neoplasias/fisiopatologia , Sítios de Splice de RNA , Splicing de RNA , Fatores de Processamento de RNA/genética
4.
Nature ; 574(7780): 707-711, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31664194

RESUMO

In cancer, recurrent somatic single-nucleotide variants-which are rare in most paediatric cancers-are confined largely to protein-coding genes1-3. Here we report highly recurrent hotspot mutations (r.3A>G) of U1 spliceosomal small nuclear RNAs (snRNAs) in about 50% of Sonic hedgehog (SHH) medulloblastomas. These mutations were not present across other subgroups of medulloblastoma, and we identified these hotspot mutations in U1 snRNA in only <0.1% of 2,442 cancers, across 36 other tumour types. The mutations occur in 97% of adults (subtype SHHδ) and 25% of adolescents (subtype SHHα) with SHH medulloblastoma, but are largely absent from SHH medulloblastoma in infants. The U1 snRNA mutations occur in the 5' splice-site binding region, and snRNA-mutant tumours have significantly disrupted RNA splicing and an excess of 5' cryptic splicing events. Alternative splicing mediated by mutant U1 snRNA inactivates tumour-suppressor genes (PTCH1) and activates oncogenes (GLI2 and CCND2), and represents a target for therapy. These U1 snRNA mutations provide an example of highly recurrent and tissue-specific mutations of a non-protein-coding gene in cancer.


Assuntos
Neoplasias Cerebelares/genética , Proteínas Hedgehog/genética , Meduloblastoma/genética , RNA Nuclear Pequeno/genética , Adolescente , Adulto , Processamento Alternativo , Proteínas Hedgehog/metabolismo , Humanos , Mutação , Sítios de Splice de RNA , Splicing de RNA
5.
Proc Natl Acad Sci U S A ; 119(29): e2204527119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858325

RESUMO

Mice with insulin receptor (IR)-deficient astrocytes (GFAP-IR knockout [KO] mice) show blunted responses to insulin and reduced brain glucose uptake, whereas IR-deficient astrocytes show disturbed mitochondrial responses to glucose. While exploring the functional impact of disturbed mitochondrial function in astrocytes, we observed that GFAP-IR KO mice show uncoupling of brain blood flow with glucose uptake. Since IR-deficient astrocytes show higher levels of reactive oxidant species (ROS), this leads to stimulation of hypoxia-inducible factor-1α and, consequently, of the vascular endothelial growth factor angiogenic pathway. Indeed, GFAP-IR KO mice show disturbed brain vascularity and blood flow that is normalized by treatment with the antioxidant N-acetylcysteine (NAC). NAC ameliorated high ROS levels, normalized angiogenic signaling and mitochondrial function in IR-deficient astrocytes, and normalized neurovascular coupling in GFAP-IR KO mice. Our results indicate that by modulating glucose uptake and angiogenesis, insulin receptors in astrocytes participate in neurovascular coupling.


Assuntos
Astrócitos , Encéfalo , Insulina , Neovascularização Fisiológica , Acoplamento Neurovascular , Animais , Astrócitos/metabolismo , Encéfalo/irrigação sanguínea , Proteína Glial Fibrilar Ácida/genética , Glucose/metabolismo , Insulina/metabolismo , Camundongos , Camundongos Knockout , Espécies Reativas de Oxigênio/metabolismo , Receptor de Insulina/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Plant Physiol ; 192(1): 256-273, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36747317

RESUMO

Throughout the exploration of the soil, roots interact with their environment and adapt to different conditions. Directional root growth is guided by asymmetric molecular patterns but how these become established or are dynamically regulated is poorly understood. Asymmetric gradients of the phytohormone auxin are established during root gravitropism, mainly through directional transport mediated by polarized auxin transporters. Upon gravistimulation, PIN-FORMED2 (PIN2) is differentially distributed and accumulates at the lower root side to facilitate asymmetric auxin transport up to the elongation zone where it inhibits cell elongation. GOLVEN (GLV) peptides function in gravitropism by affecting PIN2 abundance in epidermal cells. In addition, GLV signaling through ROOT GROWTH FACTOR 1 INSENSITIVE (RGI) receptors regulates root apical meristem maintenance. Here, we show that GLV-RGI signaling in these 2 processes in Arabidopsis (Arabidopsis thaliana) can be mapped to different cells in the root tip and that, in the case of gravitropism, it operates mainly in the lateral root cap (LRC) to maintain PIN2 levels at the plasma membrane (PM). Furthermore, we found that GLV signaling upregulates the phosphorylation level of PIN2 in an RGI-dependent manner. In addition, we demonstrated that the RGI5 receptor is asymmetrically distributed in the LRC and accumulates in the lower side of the LRC after gravistimulation. Asymmetric GLV-RGI signaling in the root cap likely accounts for differential PIN2 abundance at the PM to temporarily support auxin transport up to the elongation zone, thereby representing an additional level of control on the asymmetrical auxin flux to mediate differential growth of the root.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Gravitropismo/fisiologia , Proteínas de Arabidopsis/metabolismo , Raízes de Plantas/metabolismo , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo
7.
Vet Res ; 55(1): 11, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38268053

RESUMO

Streptococcus suis is a zoonotic pathogen that causes a major health problem in the pig production industry worldwide. Spain is one of the largest pig producers in the world. This work aimed to investigate the genetic and phenotypic features of invasive S. suis isolates recovered in Spain. A panel of 156 clinical isolates recovered from 13 Autonomous Communities, representing the major pig producers, were analysed. MLST and serotyping analysis revealed that most isolates (61.6%) were assigned to ST1 (26.3%), ST123 (18.6%), ST29 (9.6%), and ST3 (7.1%). Interestingly, 34 new STs were identified, indicating the emergence of novel genetic lineages. Serotypes 9 (27.6%) and 1 (21.8%) prevailed, followed by serotypes 7 (12.8%) and 2 (12.2%). Analysis of 13 virulence-associated genes showed significant associations between ST, serotype, virulence patterns, and clinical features, evidencing particular virulence traits associated with genetic clusters. The pangenome was generated, and the core genome was distributed in 7 Bayesian groups where each group included a variable set of over- and under-represented genes of different categories. The study provides comprehensive data and knowledge to improve the design of new vaccines, antimicrobial treatments, and bacterial typing approaches.


Assuntos
Streptococcus suis , Animais , Suínos , Streptococcus suis/genética , Espanha/epidemiologia , Teorema de Bayes , Tipagem de Sequências Multilocus/veterinária , Virulência , Genômica
8.
Anal Bioanal Chem ; 416(9): 2089-2095, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38093115

RESUMO

Wearable sensors would revolutionize healthcare and personalized medicine by providing individuals with continuous and real-time data about their bodies and environments. Their integration into everyday life has the potential to enhance well-being, improve healthcare outcomes, and offer new opportunities for research. Capacitive sensors technology has great potential to enrich wearable devices, extending their use to more accurate physiological indicators. On the basis of capacitive sensors developed so far to monitor physical parameters, and taking into account the advances in capacitive biosensors, this work discusses the benefits of this type of transduction to design wearables for the monitoring of biomolecules. Moreover, it provides insights into the challenges that must be overcome to take advantage of capacitive transduction in wearable sensors for health.


Assuntos
Técnicas Biossensoriais , Dispositivos Eletrônicos Vestíveis , Humanos , Técnicas Biossensoriais/métodos , Análise Espectral
9.
Acta Paediatr ; 113(6): 1364-1372, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38403778

RESUMO

AIM: To analyse the relationships between muscular fitness (MF), fat mass (FM), fat-free mass (FFM) and its combined ratio with cardiometabolic risk (CMR) and whether the relationship between MF and CMR is mediated by body composition in schoolchildren. METHODS: A cross-sectional study was conducted on schoolchildren from Cuenca, Spain, between September and November 2017. FM and FFM were estimated using bioimpedance analysis. The CMR index was calculated from triglycerides-HDL-c ratio, arterial pressure and fasting insulin. The MF index was assessed using handgrip and standing long jump tests. Analysis of covariance models assessed CMR index differences across the MF index and the FM/FFM ratio categories. Mediation analysis examined whether the MF index and the CMR index association were mediated by FM, FFM or FM/FFM ratio. RESULTS: The analyses involved 485 schoolchildren aged 9-11 years (55.4% girls). Children with a higher MF index had a lower CMR index (p < 0.05). This association did not persist after controlling for FM/FFM. FM, FFM and FM/FFM ratio mediated the relationship between the MF index and the CMR index. CONCLUSION: Better levels of MF are associated with better cardiometabolic profile, but a healthy body composition is determinant to improve future health.


Assuntos
Fatores de Risco Cardiometabólico , Aptidão Física , Humanos , Criança , Masculino , Feminino , Estudos Transversais , Composição Corporal
10.
Proc Natl Acad Sci U S A ; 118(41)2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34607952

RESUMO

Humans have made such dramatic and permanent changes to Earth's landscapes that much of it is now substantially and irreversibly altered from its preanthropogenic state. Remote islands, until recently isolated from humans, offer insights into how these landscapes evolved in response to human-induced perturbations. However, little is known about when and how remote systems were colonized because archaeological data and historical records are scarce and incomplete. Here, we use a multiproxy approach to reconstruct the initial colonization and subsequent environmental impacts on the Azores Archipelago. Our reconstructions provide unambiguous evidence for widespread human disturbance of this archipelago starting between 700-60+50 and 850-60+60 Common Era (CE), ca. 700 y earlier than historical records suggest the onset of Portuguese settlement of the islands. Settlement proceeded in three phases, during which human pressure on the terrestrial and aquatic ecosystems grew steadily (i.e., through livestock introductions, logging, and fire), resulting in irreversible changes. Our climate models suggest that the initial colonization at the end of the early Middle Ages (500 to 900 CE) occurred in conjunction with anomalous northeasterly winds and warmer Northern Hemisphere temperatures. These climate conditions likely inhibited exploration from southern Europe and facilitated human settlers from the northeast Atlantic. These results are consistent with recent archaeological and genetic data suggesting that the Norse were most likely the earliest settlers on the islands.


Assuntos
Ecossistema , Meio Ambiente , Atividades Humanas , Migração Humana , Agricultura , Açores , Mudança Climática , Modelos Climáticos , Fezes/química , Humanos
11.
BMC Palliat Care ; 23(1): 157, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907206

RESUMO

BACKGROUND: Cancer is a disease that transcends what is purely medical, profoundly affecting the day-to-day life of both patients and family members. Previous research has shown that the consequences of cancer are greatly aggravated in patients at the end of life, at a time when they must also grapple with numerous unmet needs. The main objective of this study was to obtain more in-depth insight into these needs, primarily in patients with end-stage cancer nearing death. METHODS: Semi-structured interviews were conducted in Spain with cancer patients at the end of life (n = 3) and their family members (n = 12). The findings from the interviews were analyzed using qualitative thematic analysis and a grounded theory approach. RESULTS: Four major themes emerged from the interviews that explored the needs and concerns of patients with cancer at the end of life: (1) physical well-being (2) emotional well-being (3) social well-being and (4), needs relating to information and autonomous decision-making. The interviews also shed light on the specific needs of family members during this period, namely the difficulties of managing increased caregiver burden and maintaining a healthy work-life balance. CONCLUSIONS: A lack of support, information and transparency during a period of immense vulnerability makes the end-of-life experience even more difficult for patients with cancer. Our findings highlight the importance of developing a more in-depth understanding of the needs of this population, so that informed efforts can be made to improve palliative healthcare and implement more comprehensive care and support at the end of life.


Assuntos
Família , Neoplasias , Pesquisa Qualitativa , Assistência Terminal , Humanos , Neoplasias/psicologia , Neoplasias/terapia , Neoplasias/complicações , Masculino , Feminino , Assistência Terminal/psicologia , Assistência Terminal/métodos , Assistência Terminal/normas , Pessoa de Meia-Idade , Idoso , Família/psicologia , Espanha , Adulto , Teoria Fundamentada , Entrevistas como Assunto/métodos , Cuidadores/psicologia , Idoso de 80 Anos ou mais , Avaliação das Necessidades
12.
Int J Mol Sci ; 25(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38473705

RESUMO

Classic Hodgkin lymphoma (cHL) constitutes a B-cell neoplasm derived from germinal center lymphocytes. Despite high cure rates (80-90%) obtained with the current multiagent protocols, a significant proportion of cHL patients experience recurrences, characterized by a lower sensitivity to second-line treatments. The genomic background of chemorefractory cHL is still poorly understood, limiting personalized treatment strategies based on molecular features. In this study, using a targeted next-generation sequencing (NGS) panel specifically designed for cHL research, we compared chemosensitive and chemorefractory diagnostic tissue samples of cHL patients. Furthermore, we longitudinally examined paired diagnosis-relapsesamples of chemorefractory cHL in order to define patterns of dynamic evolution and clonal selection. Pathogenic variants in NOTCH1 and NOTCH2 genes frequently arise in cHL. Mutations in genes associated with epigenetic regulation (CREBBP and EP300) are particularly frequent in relapsed/refractory cHL. The appearance of novel clones characterized by mutations previously not identified at diagnosis is a common feature in cHL cases showing chemoresistance to frontline treatments. Our results expand current molecular and pathogenic knowledge of cHL and support the performance of molecular studies in cHL prior to the initiation of first-line therapies.


Assuntos
Doença de Hodgkin , Linfoma de Células B , Humanos , Doença de Hodgkin/patologia , Epigênese Genética , Linfoma de Células B/genética , Mutação , Centro Germinativo/metabolismo
13.
Rev Esp Enferm Dig ; 116(4): 232-233, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37204083

RESUMO

We present the case of a 52-year-old woman with a history of HBeAg-negative chronic hepatitis B virus (HBV) infection, viral load (VL) Z+<20,000U.l/ml with no evidence of liver fibrosis and, therefore, untreated. She presented to the emergency department with jaundice, epigastric pain, nausea, and vomiting. On admission, blood analysis revealed ALT 3982U/l, AST 3221U/l, Gamma-GT 80U/l, alkaline phosphatase 252U/l, LDH 960U/l, bilirrubin12.5mg/dl; no elevation of acute phase reactants, 141,000 platelets and coagulopathy with a prothrombin activity of 29%. Abdominal ultrasound showed no relevant findings. The serological profile revealed AgHBs+, anti-HBe+ y anti-HBc IgM+ and VL VHB>100 mills. Ul/ml, the remaining serology was negative and other causes of liver disease were ruled out. With the diagnosis of severe acute hepatitis (SAH) due to HBV reactivation (HBVR) treatment with entecavir was initiated. Given the analytical evolution (Table 1) and the appearance of encephalopathy grade I-II/IV, an urgent liver transplant was performed. The histological result of the explant was conclusive with intense interphase and lobular hepatitis with extensive areas of massive necrosis in both lobes, without hepatic fibrosis compatible with fulminant hepatitis (FH).


Assuntos
Hepatite A , Hepatite B Crônica , Hepatite B , Necrose Hepática Massiva , Feminino , Humanos , Pessoa de Meia-Idade , Anticorpos Anti-Hepatite B , Cirrose Hepática/complicações , Vírus da Hepatite B , Hepatite B/complicações , Hepatite B/diagnóstico
14.
BMC Oral Health ; 24(1): 474, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641652

RESUMO

BACKGROUND: Important evidence has been constantly produced and needs to be converted into practice. Professional consumption of such evidence may be a barrier to its implementation. Then, effective implementation of evidence-based interventions in clinical practice leans on the understanding of how professionals value attributes when choosing between options for dental care, permitting to guide this implementation process by maximizing strengthens and minimizing barriers related to that. METHODS: This is part of a broader project investigating the potential of incorporating scientific evidence into clinical practice and public policy recommendations and guidelines, identifying strengths and barriers in such an implementation process. The present research protocol comprises a Discrete Choice Experiment (DCE) from the Brazilian oral health professionals' perspective, aiming to assess how different factors are associated with professional decision-making in dental care, including the role of scientific evidence. Different choice sets will be developed, either focusing on understanding the role of scientific evidence in the professional decision-making process or on understanding specific attributes associated with different interventions recently tested in randomized clinical trials and available as newly produced scientific evidence to be used in clinical practice. DISCUSSION: Translating research into practice usually requires time and effort. Shortening this process may be useful for faster incorporation into clinical practice and beneficial to the population. Understanding the context and professionals' decision-making preferences is crucial to designing more effective implementation and/or educational initiatives. Ultimately, we expect to design an efficient implementation strategy that overcomes threats and potential opportunities identified during the DCEs, creating a customized structure for dental professionals. TRIAL REGISTRATION: https://osf.io/bhncv .


Assuntos
Prática Clínica Baseada em Evidências , Odontopediatria , Criança , Humanos , Projetos de Pesquisa , Assistência Odontológica , Brasil
15.
Angew Chem Int Ed Engl ; 63(1): e202314818, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37994381

RESUMO

Here we report the development of a method for the electrochemical ultrasensitive detection of antibodies that couples the programmability and versatility of DNA-based systems with the sensitivity provided by enzymatic amplification. The platform, termed Enzyme-Linked DNA Displacement (ELIDIS), is based on the use of antigen-DNA conjugates that, upon the bivalent binding of a specific target antibody, induce the release of an enzyme-DNA hybrid strand from a preformed duplex. Such enzyme-DNA hybrid strand can then be electrochemically detected with a disposable electrode with high sensitivity. We applied ELIDIS to demonstrate the sensitive (limit of detection in the picomolar range), specific and multiplexed detection of five different antibodies including three clinically relevant ones. ELIDIS is also rapid (it only requires two reaction steps), works well in complex media (serum) and is cost-effective. A direct comparison with a commercial ELISA kit for the detection of Cetuximab demonstrates the promising features of ELIDIS as a point-of-care platform for antibodies detection.


Assuntos
Técnicas Biossensoriais , DNA , DNA/genética , Anticorpos , Ensaio de Imunoadsorção Enzimática , Eletrodos , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Limite de Detecção
16.
Neurobiol Dis ; 179: 106046, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36806818

RESUMO

From a pathogenic perspective, Huntington's disease (HD) is being considered as a synaptopathy. As such, alterations in brain neurotransmitter release occur. As the activity of the sympathoadrenal axis is centrally controlled, deficits in the exocytotic release of catecholamine release may also occur. In fact, in chromaffin cells (CCs) of the adrenal medulla of the R6/1 model of HD, decrease of secretion and altered kinetics of the exocytotic fusion pore have been reported. Those alterations could be linked to mitochondrial deficits occurring in peripheral CCs, similar to those described in brain mitochondria. Here we have inquired about alterations in mitochondrial structure and function and their impact on exocytosis and calcium channel currents (ICa). We have monitored various parameters linked to those events, in wild type (WT) and the R6/1 mouse model of HD at a pre-disease stage (2 months age, 2 m), and when motor deficits are present (7 months age, 7 m). In isolated CCs from 7 m and in the adrenal medulla of R6/1 mice, we found the following alterations (with respect 7 m WT mice): (i) augmented fragmented mitochondria and oxidative stress with increased oxidized glutathione; (ii) decreased basal and maximal respiration; (iii) diminution of ATP cell levels; (iv) mitochondrial depolarization; (v) drastic decrease of catecholamine release with poorer potentiation by protonophore FCCP; (vi) decreased ICa inhibition by FCCP; and (vii) lesser potentiation by BayK8644 of ICa and smaller prolongation of current deactivation. Of note was the fact several of these alterations were already manifested in CCs from 2 m R6/1 mice at pre-disease stages. Based on those results, a plausible hypothesis can be raised in the sense that altered mitochondrial function seems to be an early primary event in HD pathogenesis. This is in line with an increasing number of mitochondrial, metabolic, and inflammatory alterations being recently reported in various HD peripheral tissues.


Assuntos
Células Cromafins , Doença de Huntington , Camundongos , Animais , Doença de Huntington/metabolismo , Cálcio/metabolismo , Camundongos Transgênicos , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/metabolismo , Células Cromafins/metabolismo , Células Cromafins/patologia , Catecolaminas , Mitocôndrias/metabolismo , Exocitose/fisiologia , Modelos Animais de Doenças
17.
Int J Med Microbiol ; 313(6): 151588, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37925748

RESUMO

Microbiological diagnosis of osteoarticular infections (OI) is crucial for a successful treatment. A prospective multicenter study including 262 synovial fluids with suspicion of acute OI was performed between July 2021 and October of 2022. BioFire Joint Infection Panel multiplex-PCR test was performed and results were compared with conventional cultures of synovial fluid specimens. In total, 136 microorganisms were detected, and fourteen samples were positive for more than one microorganism. In monomicrobial infections (n = 87) agreement with culture was 69%. In 26 samples, the multiplex PCR yield an additional positive result when culture result was negative. It helped in the detection of fastidious microorganisms as K. kingae and N. gonorrhoeae. This multiplex PCR has proven to be a useful technique that can be used for patients with high suspicion of acute OI in a rapid and automated manner.


Assuntos
Artrite Infecciosa , Humanos , Estudos Prospectivos , Artrite Infecciosa/diagnóstico , Artrite Infecciosa/microbiologia , Reação em Cadeia da Polimerase Multiplex/métodos
18.
Hum Reprod ; 38(11): 2187-2195, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37697661

RESUMO

STUDY QUESTION: Is the abundance of certain biochemical compounds in human cumulus cells (CCs) related to oocyte quality? SUMMARY ANSWER: Malonate, 5-oxyproline, and erythronate were positively associated with pregnancy potential. WHAT IS KNOWN ALREADY: CCs are removed and discarded prior to ICSI, thereby constituting an interesting biological material on which to perform molecular analysis aimed to predict oocyte developmental competence. Mitochondrial DNA content and transcriptional analyses in CC have been shown to provide a poor predictive value of oocyte competence, but the untargeted analysis of biochemical compounds (metabolomics) has been unexplored. STUDY DESIGN, SIZE, DURATION: CCs were obtained from three groups of cumulus-oocyte complexes (COCs) of known developmental potential: oocytes not developing to blastocyst following ICSI (Bl-); oocytes developing to blastocyst but failing to establish pregnancy following embryo transfer (P-); and oocytes developing to blastocyst able to establish a pregnancy (P+). Metabolomics analyses were performed on 12 samples per group, each sample comprising the CC recovered from a single COC. PARTICIPANTS/MATERIALS, SETTING, METHODS: Human CC samples were obtained from IVF treatments. Only unfrozen oocytes and embryos not submitted to preimplantation genetic testing were included in the analysis. Metabolomics analysis was performed by ultra-high performance liquid chromatography-tandem mass spectroscopy. MAIN RESULTS AND THE ROLE OF CHANCE: The analysis identified 98 compounds, five of which were differentially abundant (P < 0.05) between groups: asparagine, proline, and malonate were less abundant in P- compared to Bl-, malonate and 5-oxoproline were less abundant in P- group compared to P+, and erythronate was less abundant in Bl- group compared to P+. No significant association between the abundance of the compounds identified and donor age or BMI was noted. LIMITATIONS, REASONS FOR CAUTION: Data dispersion and the lack of coherence between developmental groups preclude the direct use of metabolic markers in clinical practice, where the uterine environment plays a major role in pregnancy outcome. The abundance of other compounds not detected by the analysis may be associated with oocyte competence. As donors were lean (only two with BMI > 30 kg/m2) and young (<34 years old), a possible effect of obesity or advanced age on the CC metabolome could not be determined. WIDER IMPLICATIONS OF THE FINDINGS: The abundance of malonate, 5-oxyproline, and erythronate in CC was significantly higher in COCs ultimately establishing pregnancy, providing clues on the pathways required for oocyte competence. The untargeted analysis uncovered the presence of compounds that were not expected in CC, such as ß-citrylglutamate and the neurotransmitter N-acetyl-aspartyl-glutamate, which may play roles in chromatin remodeling and signaling, respectively. STUDY FUNDING/COMPETING INTEREST(S): Research was supported by the Industrial Doctorate Project IND2017/BIO-7748 funded by Madrid Region Government. The authors declare no competing interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Células do Cúmulo , Oócitos , Feminino , Humanos , Gravidez , Adulto , Células do Cúmulo/metabolismo , Hidroxiprolina/metabolismo , Hidroxiprolina/farmacologia , Oócitos/metabolismo , Oogênese , Malonatos/metabolismo , Malonatos/farmacologia
19.
J Exp Bot ; 74(14): 4031-4049, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37004244

RESUMO

Lateral root initiation requires the accumulation of auxin in lateral root founder cells, yielding a local auxin maximum. The positioning of auxin maxima along the primary root determines the density and spacing of lateral roots. The GOLVEN6 (GLV6) and GLV10 signaling peptides and their receptors have been established as regulators of lateral root spacing via their inhibitory effect on lateral root initiation in Arabidopsis. However, it was unclear how these GLV peptides interfere with auxin signaling or homeostasis. Here, we show that GLV6/10 signaling regulates the expression of a subset of auxin response genes, downstream of the canonical auxin signaling pathway, while simultaneously inhibiting the establishment of auxin maxima within xylem-pole pericycle cells that neighbor lateral root initiation sites. We present genetic evidence that this inhibitory effect relies on the activity of the PIN3 and PIN7 auxin export proteins. Furthermore, GLV6/10 peptide signaling was found to enhance PIN7 abundance in the plasma membranes of xylem-pole pericycle cells, which likely stimulates auxin efflux from these cells. Based on these findings, we propose a model in which the GLV6/10 signaling pathway serves as a negative feedback mechanism that contributes to the robust patterning of auxin maxima along the primary root.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácidos Indolacéticos/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Raízes de Plantas/metabolismo , Retroalimentação , Arabidopsis/metabolismo , Peptídeos/metabolismo , Regulação da Expressão Gênica de Plantas
20.
Anal Bioanal Chem ; 415(18): 3831-3846, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36702904

RESUMO

The discovery of new molecular biomarkers of cancer during the last decades and the development of new diagnostic devices exploiting those have significantly contributed to the clinical analysis of cancer and to improve the outcomes. Among those, liquid biopsy sensors exploiting aptamers for the detection of cancer biomarkers in body fluids are useful and accurate tools for a fast and inexpensive non-invasive screening of population. The incorporation of aptamers in electrochemical sandwich biosensors using enzyme labels, a so-called ELASA, has demonstrated its utility to improve the detection schemes. In this review, we overview the existing ELASA assays for numerous cancer biomarkers as alternatives to the traditional ELISA and discuss their possibilities to reach the market, currently dominated by optical immunoassays.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Neoplasias , Aptâmeros de Nucleotídeos/química , Ensaio de Imunoadsorção Enzimática , Imunoensaio , Biomarcadores Tumorais , Técnicas Eletroquímicas , Neoplasias/diagnóstico
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