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1.
Nature ; 632(8024): 357-365, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38987585

RESUMO

In lactating mothers, the high calcium (Ca2+) demand for milk production triggers significant bone loss1. Although oestrogen normally counteracts excessive bone resorption by promoting bone formation, this sex steroid drops precipitously during this postpartum period. Here we report that brain-derived cellular communication network factor 3 (CCN3) secreted from KISS1 neurons of the arcuate nucleus (ARCKISS1) fills this void and functions as a potent osteoanabolic factor to build bone in lactating females. We began by showing that our previously reported female-specific, dense bone phenotype2 originates from a humoral factor that promotes bone mass and acts on skeletal stem cells to increase their frequency and osteochondrogenic potential. This circulatory factor was then identified as CCN3, a brain-derived hormone from ARCKISS1 neurons that is able to stimulate mouse and human skeletal stem cell activity, increase bone remodelling and accelerate fracture repair in young and old mice of both sexes. The role of CCN3 in normal female physiology was revealed after detecting a burst of CCN3 expression in ARCKISS1 neurons coincident with lactation. After reducing CCN3 in ARCKISS1 neurons, lactating mothers lost bone and failed to sustain their progeny when challenged with a low-calcium diet. Our findings establish CCN3 as a potentially new therapeutic osteoanabolic hormone for both sexes and define a new maternal brain hormone for ensuring species survival in mammals.


Assuntos
Densidade Óssea , Osso e Ossos , Encéfalo , Hormônios , Mães , Proteína Sobre-Expressa em Nefroblastoma , Osteogênese , Adolescente , Animais , Feminino , Humanos , Masculino , Camundongos , Envelhecimento , Núcleo Arqueado do Hipotálamo/citologia , Núcleo Arqueado do Hipotálamo/metabolismo , Osso e Ossos/citologia , Osso e Ossos/metabolismo , Remodelação Óssea , Reabsorção Óssea/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Cálcio/administração & dosagem , Cálcio/metabolismo , Lactação/metabolismo , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Células-Tronco/metabolismo , Células-Tronco/citologia , Proteína Sobre-Expressa em Nefroblastoma/metabolismo , Hormônios/metabolismo
2.
Proc Natl Acad Sci U S A ; 115(31): E7351-E7360, 2018 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-30021854

RESUMO

Neuroblastoma is a neural crest-derived childhood tumor of the peripheral nervous system in which MycN amplification is a hallmark of poor prognosis. Here we show that MycN is expressed together with phosphorylation-stabilizing factor CIP2A in regions of the neural plate destined to form the CNS, but MycN is excluded from the neighboring neural crest stem cell domain. Interestingly, ectopic expression of MycN or CIP2A in the neural crest domain biases cells toward CNS-like neural stem cells that express Sox2. Consistent with this, some forms of neuroblastoma have been shown to share transcriptional resemblance with CNS neural stem cells. As high MycN/CIP2A levels correlate with poor prognosis, we posit that a MycN/CIP2A-mediated cell-fate bias may reflect a possible mechanism underlying early priming of some aggressive forms of neuroblastoma. In contrast to MycN, its paralogue cMyc is normally expressed in the neural crest stem cell domain and typically is associated with better overall survival in clinical neuroblastoma, perhaps reflecting a more "normal" neural crest-like state. These data suggest that priming for some forms of aggressive neuroblastoma may occur before neural crest emigration from the CNS and well before sympathoadrenal specification.


Assuntos
Autoantígenos/fisiologia , Proteínas de Membrana/fisiologia , Proteína Proto-Oncogênica N-Myc/fisiologia , Crista Neural/citologia , Células-Tronco Neurais/fisiologia , Neuroblastoma/etiologia , Autoantígenos/análise , Movimento Celular , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Membrana/análise , Proteína Proto-Oncogênica N-Myc/análise , Neuroblastoma/patologia , Fatores de Transcrição SOXB1/análise
3.
Int J Mol Sci ; 22(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065402

RESUMO

Lung carcinoma is still the most common malignancy worldwide. One of the major subtypes of non-small cell lung cancer (NSCLC) is adenocarcinoma (AC). As driver mutations and hence therapies differ in AC subtypes, we theorized that the expression and function of ABC drug transporters important in multidrug resistance (MDR) would correlate with characteristic driver mutations KRAS or EGFR. Cisplatin resistance (CR) was generated in A549 (KRAS) and PC9 (EGFR) cell lines and gene expression was tested. In three-dimensional (3D) multicellular aggregate cultures, both ABCB1 and ABCG2 transporters, as well as the WNT microenvironment, were investigated. ABCB1 and ABCG2 gene expression levels were different in primary AC samples and correlated with specific driver mutations. The drug transporter expression pattern of parental A549 and PC9, as well as A549-CR and PC9-CR, cell lines differed. Increased mRNA levels of ABCB1 and ABCG2 were detected in A549-CR cells, compared to parental A549, while the trend observed in the case of PC9 cells was different. Dominant alterations were observed in LEF1, RHOU and DACT1 genes of the WNT signalling pathway in a mutation-dependent manner. The study confirmed that, in lung AC-s, KRAS and EGFR driver mutations differentially affect both drug transporter expression and the cisplatin-induced WNT signalling microenvironment.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/genética , Mutação/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Células A549 , Idoso , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular , Linhagem Celular Tumoral , Cisplatino/farmacologia , Receptores ErbB/genética , Feminino , Expressão Gênica/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Microambiente Tumoral/genética
4.
Respir Res ; 21(1): 120, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32434541

RESUMO

BACKGROUND: The predominant metastatic site of lung cancer (LC) is the brain. Although outdated, conventional cisplatin treatment is still the main therapeutic approach for patients with advanced non-small cell lung cancer (NSCLC), since targeted therapy that offers better tumor control is not always possible. In the present study brain metastasis associated cytokine expression was investigated in primary NSCLC adenocarcinoma (AC) tissues with known oncogenic mutations in the presence or absence of platina based and tyrosine kinase inhibitor (TKI) drugs. METHODS: Primary lung tumor samples were isolated, DNA was sequenced and then the samples were grouped based on mutation. Experiments were also performed using KRAS mutant A549 and EGFR mutant PC-9 cells. Drug response was analyzed in three dimensional (3D) tissue cultures. We assessed drug response and IL-6 and IL-8 cytokine expression in relation to cellular invasion using ATP dependent cell viability, qRT-PCR analysis, cytokine bead array, and migration assay. RESULTS: In 3D co-cultures, primary NSCLC derived cells harboring EGFR mutation responded better to erlotinib treatment than KRAS mutant or KRAS/EGFR wild type (WT) cancer cells. In contrast, under the same culture conditions KRAS/EGFR WT or KRAS mutant cancer cells are more sensitive to cisplatin than EGFR mutant cells. Drug response and pro-inflammatory cytokine production varied depending on the driver mutations. Cisplatin but not erlotinib increased both IL-6 and IL-8 secretion and only IL-6 increased cellular migration and proliferation. CONCLUSION: In vitro assays are available to determine the response to planned therapeutic approach of lung cancer subtypes. The sequence of administration of therapeutic drugs determines cytokine production and therefore therapeutic response.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Cisplatino/uso terapêutico , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Neoplasias Pulmonares/metabolismo , Mutação/fisiologia , Células A549 , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Cisplatino/farmacologia , Humanos , Interleucina-6/genética , Interleucina-8/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação/efeitos dos fármacos
5.
J Basic Microbiol ; 60(7): 574-584, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32449553

RESUMO

The P-type ATPase CrpA is an important Cu2+ /Cd2+ pump in the Aspergilli, significantly contributing to the heavy metal stress tolerance of these ascomycetous fungi. As expected, the deletion of crpA resulted in Cu2+ /Cd2+ -sensitive phenotypes in Aspergillus nidulans on stress agar plates inoculated with conidia. Nevertheless, paradoxical growth stimulations were observed with the ΔcrpA strain in both standard Cu2+ stress agar plate experiments and cellophane colony harvest (CCH) cultures, when exposed to Cd2+ . These observations reflect efficient compensatory mechanisms for the loss of CrpA operating under these experimental conditions. It is remarkable that the ΔcrpA strain showed a 2.7 times higher Cd biosorption capacity in CCH cultures, which may facilitate the development of new, fungal biomass-based bioremediation technologies to extract harmful Cd2+ ions from the environment. The nullification of crpA also significantly changed the spatial distribution of Cu and Cd in CCH cultures, as demonstrated by the combined particle-induced X-ray emission and scanning transmission ion microscopy technique. Most important, the centers of gravity for Cu and Cd accumulations of the ΔcrpA colonies shifted toward the older regions as compared with wild-type surface cultures.


Assuntos
Aspergillus nidulans/metabolismo , Biodegradação Ambiental , Cádmio/análise , Proteínas de Transporte de Cátions/genética , Cobre/análise , Solo/química , Águas Residuárias/química
6.
Anal Chem ; 89(3): 1558-1564, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28208274

RESUMO

There are various liquid materials whose elemental composition is of interest in various fields of science and technology. In many cases, sample preparation or the extraction can be complicated, or it would destroy the original environment before the analysis (for example, in the case of biological samples). However, multielement direct analysis of liquid samples can be realized by an external PIXE-PIGE measurement system. Particle-induced X-ray and gamma-ray emission spectroscopy (PIXE, PIGE) techniques were applied in external (in-air) microbeam configuration for the trace and main element determination of liquid samples. The direct analysis of standard solutions of several metal salts and human blood samples (whole blood, blood serum, blood plasma, and formed elements) was realized. From the blood samples, Na, P, S, Cl, K, Ca, Fe, Cu, Zn, and Br elemental concentrations were determined. The focused and scanned ion beam creates an opportunity to analyze very small volume samples (∼10 µL). As the sample matrix consists of light elements, the analysis is possible at ppm level. Using this external beam setup, it was found that it is possible to determine elemental composition of small-volume liquid samples routinely, while the liquid samples do not require any preparation processes, and thus, they can be analyzed directly. In the case of lower concentrations, the method is also suitable for the analysis (down to even ∼1 ppm level) but with less accuracy and longer measurement times.


Assuntos
Espectrometria por Raios X/métodos , Oligoelementos/sangue , Humanos , Íons/química , Limite de Detecção , Prótons , Espectrometria por Raios X/instrumentação
7.
Nat Neurosci ; 27(6): 1176-1186, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38684893

RESUMO

Reliable execution of precise behaviors requires that brain circuits are resilient to variations in neuronal dynamics. Genetic perturbation of the majority of excitatory neurons in HVC, a brain region involved in song production, in adult songbirds with stereotypical songs triggered severe degradation of the song. The song fully recovered within 2 weeks, and substantial improvement occurred even when animals were prevented from singing during the recovery period, indicating that offline mechanisms enable recovery in an unsupervised manner. Song restoration was accompanied by increased excitatory synaptic input to neighboring, unmanipulated neurons in the same brain region. A model inspired by the behavioral and electrophysiological findings suggests that unsupervised single-cell and population-level homeostatic plasticity rules can support the functional restoration after large-scale disruption of networks that implement sequential dynamics. These observations suggest the existence of cellular and systems-level restorative mechanisms that ensure behavioral resilience.


Assuntos
Tentilhões , Plasticidade Neuronal , Neurônios , Vocalização Animal , Animais , Vocalização Animal/fisiologia , Neurônios/fisiologia , Plasticidade Neuronal/fisiologia , Tentilhões/fisiologia , Masculino , Aprendizagem/fisiologia
8.
Environ Sci Pollut Res Int ; 31(34): 47258-47274, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38987520

RESUMO

This study, conducted in Debrecen, Hungary, aimed to analyse atmospheric particulate matter (APM or PM) through radiocarbon and PIXE analyses during the winter smog (23-25 January) and spring (15-18 May) seasons. The information presented in this pilot study aims to provide insight into the importance of utilising detailed characteristics of the mass size distributions of fossil carbon (ff) and contemporary carbon (fC) content. Additionally, it seeks to compare these characteristics with the size distributions of various elements to enable even more accurate PM source identification. In winter, APM concentrations were 86.27 µg/m3 (total), 17.07 µg/m3 (fC) and 10.4 µg/m3 (ff). In spring, these values changed to 29.5 µg/m3, 2.64 µg/m3 and 7.01 µg/m3, respectively. Notably, differences in mass size distribution patterns were observed between the two seasons, suggesting varied sources for contemporary carbon. Biomass burning emerged as a crucial source during the smog period, supported by similar MMAD (Mass Median Aerodynamic Diameter) values and a strong correlation (r = 0.95, p < 0.01) between potassium and fC. In spring, a significant change in the concentration and distribution of fC occurred, with a broad, coarse mode and a less prominent accumulation mode. Ff was found to have similar distributions as PM, with nearly the same MMADs, during both periods. Finally, a comprehensive comparison of modal characteristics identified specific sources for the various components, including biomass burning, vehicle exhaust, coal and oil combustion, vehicle non-exhaust, road dust, tyre abrasion, mineral dust and biogenic emission. This study showcases how using radiocarbon and PIXE analysis in size distribution data can enhance our understanding of the sources of PM and their effects on different size fractions of PM.


Assuntos
Aerossóis , Poluentes Atmosféricos , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado , Aerossóis/análise , Projetos Piloto , Poluentes Atmosféricos/análise , Material Particulado/análise , Monitoramento Ambiental/métodos , Hungria , Estações do Ano , Cidades , Radioisótopos de Carbono/análise
9.
J Homosex ; 70(7): 1386-1410, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35179446

RESUMO

Sexual and gender minorities often experience discrimination or stigmatization during health encounters. When patients feel stigmatized, they are more likely to delay seeking help and it affects patient cooperation and compliance, thus undermining therapeutic efficacy itself. We examined knowledge and attitude toward LGBT+ people among Hungarian (n = 743) and foreign (n = 130) medical students of the four Hungarian medical universities and 188 students from other faculties. Homonegativity and inadequate knowledge about sexual minority individuals are correlated with male gender, conservative political views, religiosity, religious behavior, and the absence of LGBT+ acquaintance. Medical students show more negative attitudes than students from other disciplines, although foreign medical students were more accepting than Hungarian program students. Further investigation of sexual minority-related content of the Hungarian medical education and revising the written and hidden curriculum would be desired, as well as collecting data from postgraduate students, physicians, and wide range of university faculties.


Assuntos
Minorias Sexuais e de Gênero , Estudantes de Medicina , Humanos , Masculino , Universidades , Hungria , Atitude
10.
HRB Open Res ; 6: 5, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-39280894

RESUMO

Background: Patient experience is routinely collected in the clinical environment in many different ways throughout various person-provider encounters, but so far limited research focused on understanding the methods of using it to improve the quality of healthcare. This paper presents a protocol for a methodological scoping review examining the methods of obtaining, analysing, reporting, and using patient experience data for quality improvement in rehabilitation settings. Methods: The scoping review will be conducted according to the guidelines from the Joanna Briggs Institute (JBI) Manual for Evidence Synthesis and the methodological framework by Arksey & O'Malley. A comprehensive search of the literature will be performed using a three-step search strategy: an initial limited search of two databases was already performed and helped to identified relevant key words and index terms. The developed search string will be adapted and applied across four databases. This will be followed by search of the reference lists of selected sources and hand-search relevant data-hubs. Studies with a clear focus on patient experience or feedback collected or used for healthcare improvement in rehabilitation context, will be included. A data extraction framework will be developed and piloted to guide the literature screening and data charting. Qualitative content analysis will be employed to address research questions and the results will be presented - beside the descriptive format - as a map of data in chart and tabular formats. Conclusions: This scoping review will show the extent and scope of the literature on the applied methods of collecting, communicating, and using patient experience for quality improvement in post-acute rehabilitation settings and will evaluate and map the evidence on these topics. The findings will inform a research project entitled "An exploration into the use of patient experience to inform improvement in a National Rehabilitation Hospital".

11.
bioRxiv ; 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37292888

RESUMO

Maintaining motor skills is crucial for an animal's survival, enabling it to endure diverse perturbations throughout its lifespan, such as trauma, disease, and aging. What mechanisms orchestrate brain circuit reorganization and recovery to preserve the stability of behavior despite the continued presence of a disturbance? To investigate this question, we chronically silenced a fraction of inhibitory neurons in a brain circuit necessary for singing in zebra finches. Song in zebra finches is a complex, learned motor behavior and central to reproduction. This manipulation altered brain activity and severely perturbed song for around two months, after which time it was precisely restored. Electrophysiology recordings revealed abnormal offline dynamics, resulting from chronic inhibition loss, some aspects of which returned to normal as the song recovered. However, even after the song had fully recovered, the levels of neuronal firing in the premotor and motor areas did not return to a control-like state. Single-cell RNA sequencing revealed that chronic silencing of interneurons led to elevated levels of microglia and MHC I, which were also observed in normal juveniles during song learning. These experiments demonstrate that the adult brain can overcome extended periods of abnormal activity, and precisely restore a complex behavior, without recovering normal neuronal dynamics. These findings suggest that the successful functional recovery of a brain circuit after a perturbation can involve more than mere restoration to its initial configuration. Instead, the circuit seems to adapt and reorganize into a new state capable of producing the original behavior despite the persistence of some abnormal neuronal dynamics.

12.
J Homosex ; 67(10): 1429-1446, 2020 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31034340

RESUMO

Discrimination that LGBTQ individuals experience in health care settings might affect their health and intention of using health care services. However, health needs of LGBTQ patients are still inappropriately addressed in the medical curriculum. First-, third-, and fourth-year medical students (N = 569) from the four Hungarian medical universities participated in a study in 2017 to assess knowledge about homosexuality, homonegativity, and their attitude as health care professionals toward sexual minorities. We found that higher levels of knowledge about homosexuality were associated with lower levels of homonegativity, upper-grade level in university, not being religious, and having close LGBTQ acquaintances. Our results suggest that it may be necessary to introduce LGBTQ themes in the medical curricula (not only in Hungary, but also in other countries) in order to improve the knowledge and attitude of medical students and thereby improve the health care of LGBTQ individuals.


Assuntos
Atitude do Pessoal de Saúde , Bissexualidade , Conhecimentos, Atitudes e Prática em Saúde , Homossexualidade , Minorias Sexuais e de Gênero , Estudantes de Medicina , Pessoas Transgênero , Adulto , Feminino , Humanos , Hungria , Masculino , Inquéritos e Questionários , Universidades
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