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1.
J Microsc ; 2024 Apr 25.
Artículo en Italiano | MEDLINE | ID: mdl-38661499

RESUMEN

Since its introduction in 2017, MINFLUX nanoscopy has shown that it can visualise fluorescent molecules with an exceptional localisation precision of a few nanometres. In this overview, we provide a brief insight into technical implementations, fluorescent marker developments and biological studies that have been conducted in connection with MINFLUX imaging and tracking. We also formulate ideas on how MINFLUX nanoscopy and derived technologies could influence bioimaging in the future. This insight is intended as a general starting point for an audience looking for a brief overview of MINFLUX nanoscopy from theory to application.

2.
J Microsc ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38618985

RESUMEN

The structure of the cell nucleus of higher organisms has become a major topic of advanced light microscopy. So far, a variety of methods have been applied, including confocal laser scanning fluorescence microscopy, 4Pi, STED and localisation microscopy approaches, as well as different types of patterned illumination microscopy, modulated either laterally (in the object plane) or axially (along the optical axis). Based on our experience, we discuss here some application perspectives of Modulated Illumination Microscopy (MIM) and its combination with single-molecule localisation microscopy (SMLM). For example, spatially modulated illumination microscopy/SMI (illumination modulation along the optical axis) has been used to determine the axial extension (size) of small, optically isolated fluorescent objects between ≤ 200 nm and ≥ 40 nm diameter with a precision down to the few nm range; it also allows the axial positioning of such structures down to the 1 nm scale; combined with laterally structured illumination/SIM, a 3D localisation precision of ≤1 nm is expected using fluorescence yields typical for SMLM applications. Together with the nanosizing capability of SMI, this can be used to analyse macromolecular nuclear complexes with a resolution approaching that of cryoelectron microscopy.

3.
Viruses ; 15(12): 1-15, dez 4, 2023. tab, mapa
Artículo en Inglés | RSDM | ID: biblio-1531383

RESUMEN

Emerging zoonotic diseases are an increasing threat to public health. There is little data on the seroprevalence of zoonotic diseases among pastoralists in the country. We aim to carry out a cross-sectional study on the prevalence of major zoonotic diseases among pastoral communities in the Caia and Búzi districts. Methods: Between January and December 2018, a questionnaire was used to solicit socio-demographic data from consenting pastoralists with the collection of blood samples in the Caia and Búzi districts of the Sofala province. All samples were tested using ELISA commercial reagents for the detection of IgM antibodies against Brucella and Leptospira. Likewise, IgM and IgG antibodies against Rickettsia and CCHFV were determined using ELISA kits. Results: A total of 218 samples were tested, of which 43.5% (95/218) were from the district of Caia and 56.4% (123/218) from the Búzi district. Results from both districts showed that the seroprevalence of IgM antibodies against Brucella and Leptospira was 2.7% (6/218) and 30.3% (67/218), respectively. Positivity rates for IgM and IgG anti-Rickettsia and CCHFV were 8.7% (19/218), 2.7% (6/218), 4.1% (9/218), and 0.9% (2/218), respectively. Conclusions: Results from our study showed evidence of antibodies due to exposure to Brucella, Leptospira, Rickettsia, and CCHFV with antibodies against Leptospira and Rickettsia being the most prevalent. Hence, laboratory diagnosis of zoonotic diseases is essential in the early detection of outbreaks, the identification of silent transmission, and the etiology of non-febrile illness in a pastoral community. There is a need to develop public health interventions that will reduce the risk of transmission.


Asunto(s)
Humanos , Masculino , Femenino , Brucella/virología , Fiebre Hemorrágica de Crimea/virología , Anticuerpos Antivirales/inmunología , Rickettsia/crecimiento & desarrollo , Virus Hantaan/inmunología , Fiebre Hemorrágica de Crimea/prevención & control , Leptospira/virología , Mozambique
4.
Viruses ; 15(12)2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38140620

RESUMEN

BACKGROUND: Emerging zoonotic diseases are an increasing threat to public health. There is little data on the seroprevalence of zoonotic diseases among pastoralists in the country. We aim to carry out a cross-sectional study on the prevalence of major zoonotic diseases among pastoral communities in the Caia and Búzi districts. METHODS: Between January and December 2018, a questionnaire was used to solicit socio-demographic data from consenting pastoralists with the collection of blood samples in the Caia and Búzi districts of the Sofala province. All samples were tested using ELISA commercial reagents for the detection of IgM antibodies against Brucella and Leptospira. Likewise, IgM and IgG antibodies against Rickettsia and CCHFV were determined using ELISA kits. RESULTS: A total of 218 samples were tested, of which 43.5% (95/218) were from the district of Caia and 56.4% (123/218) from the Búzi district. Results from both districts showed that the seroprevalence of IgM antibodies against Brucella and Leptospira was 2.7% (6/218) and 30.3% (67/218), respectively. Positivity rates for IgM and IgG anti-Rickettsia and CCHFV were 8.7% (19/218), 2.7% (6/218), 4.1% (9/218), and 0.9% (2/218), respectively. CONCLUSIONS: Results from our study showed evidence of antibodies due to exposure to Brucella, Leptospira, Rickettsia, and CCHFV with antibodies against Leptospira and Rickettsia being the most prevalent. Hence, laboratory diagnosis of zoonotic diseases is essential in the early detection of outbreaks, the identification of silent transmission, and the etiology of non-febrile illness in a pastoral community. There is a need to develop public health interventions that will reduce the risk of transmission.


Asunto(s)
Brucella , Virus de la Fiebre Hemorrágica de Crimea-Congo , Fiebre Hemorrágica de Crimea , Leptospira , Rickettsia , Animales , Humanos , Estudios Seroepidemiológicos , Mozambique , Estudios Transversales , Anticuerpos Antivirales , Zoonosis , Inmunoglobulina G , Inmunoglobulina M
5.
J Biol Chem ; 299(10): 105216, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37660918

RESUMEN

The Vps10p-domain (Vps10p-D) receptor family consists of Sortilin, SorLA, SorCS1, SorCS2, and SorCS3. They mediate internalization and intracellular sorting of specific cargo in various cell types, but underlying molecular determinants are incompletely understood. Deciphering the dynamic intracellular itineraries of Vps10p-D receptors is crucial for understanding their role in physiological and cytopathological processes. However, studying their spatial and temporal dynamics by live imaging has been challenging so far, as terminal tagging with fluorophores presumably impedes several of their protein interactions and thus functions. Here, we addressed the lack of appropriate tools and developed functional versions of all family members internally tagged in their ectodomains. We predict folding of the newly designed receptors by bioinformatics and show their exit from the endoplasmic reticulum. We examined their subcellular localization in immortalized cells and primary cultured neurons by immunocytochemistry and live imaging. This was, as far as known, identical to that of wt counterparts. We observed homodimerization of fluorophore-tagged SorCS2 by coimmunoprecipitation and fluorescence lifetime imaging, suggesting functional leucine-rich domains. Through ligand uptake experiments, live imaging and fluorescence lifetime imaging, we show for the first time that all Vps10p-D receptors interact with the neurotrophin brain-derived neurotrophic factor and mediate its uptake, indicating functionality of the Vps10p-Ds. In summary, we developed versions of all Vps10p-D receptors, with internal fluorophore tags that preserve several functions of the cytoplasmic and extracellular domains. These newly developed fluorophore-tagged receptors are likely to serve as powerful functional tools for accurate live studies of the individual cellular functions of Vps10p-D receptors.

6.
BMJ Open ; 13(6): e067941, 2023 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-37290945

RESUMEN

INTRODUCTION: We previously assessed the effect of an onsite sanitation intervention in informal neighbourhoods of urban Maputo, Mozambique on enteric pathogen detection in children after 2 years of follow-up (Maputo Sanitation (MapSan) trial, ClinicalTrials.gov: NCT02362932). We found significant reductions in Shigella and Trichuris prevalence but only among children born after the intervention was delivered. In this study, we assess the health impacts of the sanitation intervention after 5 years among children born into study households postintervention. METHODS AND ANALYSIS: We are conducting a cross-sectional household study of enteric pathogen detection in child stool and the environment at compounds (household clusters sharing sanitation and outdoor living space) that received the pour-flush toilet and septic tank intervention at least 5 years prior or meet the original criteria for trial control sites. We are enrolling at least 400 children (ages 29 days to 60 months) in each treatment arm. Our primary outcome is the prevalence of 22 bacterial, protozoan, and soil transmitted helminth enteric pathogens in child stool using the pooled prevalence ratio across the outcome set to assess the overall intervention effect. Secondary outcomes include the individual pathogen detection prevalence and gene copy density of 27 enteric pathogens (including viruses); mean height-for-age, weight-for-age, and weight-for-height z-scores; prevalence of stunting, underweight, and wasting; and the 7-day period prevalence of caregiver-reported diarrhoea. All analyses are adjusted for prespecified covariates and examined for effect measure modification by age. Environmental samples from study households and the public domain are assessed for pathogens and faecal indicators to explore environmental exposures and monitor disease transmission. ETHICS AND DISSEMINATION: Study protocols have been reviewed and approved by human subjects review boards at the Ministry of Health, Republic of Mozambique and the University of North Carolina at Chapel Hill. Deidentified study data will be deposited at https://osf.io/e7pvk/. TRIAL REGISTRATION NUMBER: ISRCTN86084138.


Asunto(s)
Diarrea , Saneamiento , Humanos , Estudios Transversales , Diarrea/epidemiología , Diarrea/prevención & control , Diarrea/microbiología , Estudios de Seguimiento , Mozambique/epidemiología , Saneamiento/métodos , Recién Nacido , Lactante , Preescolar
7.
Res Pract Thromb Haemost ; 7(4): 100154, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37222974

RESUMEN

Background: Platelets contain high levels of amyloid ß (Aß) peptides and have been suggested to participate in the deposition of amyloid plaques in Alzheimer's Disease (AD). Objectives: This study aimed to determine whether human platelets release pathogenic Aß peptides Aß1-42 and Aß1-40 and to characterise the mechanisms regulating this phenomenon. Methods and Results: Enzyme-linked immunosorbent assays (ELISAs) revealed that the haemostatic stimulus thrombin and the pro-inflammatory molecule lipopolysaccharide (LPS) induce platelet release of both Aß1-42 and Aß1-40. Notably, LPS preferentially induced the release of Aß1-42, which was potentiated by the reduction of oxygen from atmospheric levels to physiological hypoxia. The selective ß secretase (BACE) inhibitor LY2886721 showed no effect on the release of either Aß1-40 or Aß1-42 in our ELISA experiments. This suggested a store-and-release mechanism that was confirmed in immunostaining experiments showing co-localisation of cleaved Aß peptides with platelet alpha granules. Conclusions: Taken together, our data suggest that human platelets release pathogenic Aß peptides as a result of a store-and-release mechanism rather than a de novo proteolytic event. Although further studies are required to fully characterise this phenomenon, we suggest the possibility of a role for platelets in the deposition of Aß peptides and the formation of amyloid plaques. Interestingly, the combination of hypoxia and inflammation that we simulated in vitro with reduced oxygen tension and LPS may increase the release of fibrillogenic Aß1-42 and, consequently, exacerbate amyloid plaque deposition in the brain of AD patients.

8.
Acta Biomater ; 162: 254-265, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36878337

RESUMEN

Bone fragility is a profound complication of type 1 diabetes mellitus (T1DM), increasing patient morbidity. Within the mineralized bone matrix, osteocytes build a mechanosensitive network that orchestrates bone remodeling; thus, osteocyte viability is crucial for maintaining bone homeostasis. In human cortical bone specimens from individuals with T1DM, we found signs of accelerated osteocyte apoptosis and local mineralization of osteocyte lacunae (micropetrosis) compared with samples from age-matched controls. Such morphological changes were seen in the relatively young osteonal bone matrix on the periosteal side, and micropetrosis coincided with microdamage accumulation, implying that T1DM drives local skeletal aging and thereby impairs the biomechanical competence of the bone tissue. The consequent dysfunction of the osteocyte network hampers bone remodeling and decreases bone repair mechanisms, potentially contributing to the enhanced fracture risk seen in individuals with T1DM. STATEMENT OF SIGNIFICANCE: Type 1 diabetes mellitus (T1DM) is a chronic autoimmune disease that causes hyperglycemia. Increased bone fragility is one of the complications associated with T1DM. Our latest study on T1DM-affected human cortical bone identified the viability of osteocytes, the primary bone cells, as a potentially critical factor in T1DM-bone disease. We linked T1DM with increased osteocyte apoptosis and local accumulation of mineralized lacunar spaces and microdamage. Such structural changes in bone tissue suggest that T1DM speeds up the adverse effects of aging, leading to the premature death of osteocytes and potentially contributing to diabetes-related bone fragility.


Asunto(s)
Diabetes Mellitus Tipo 1 , Osteocitos , Humanos , Envejecimiento , Huesos , Apoptosis
9.
Quad. psicol. (Bellaterra, Internet) ; 25(1): e1729, 06-03-2023. tab, graf
Artículo en Portugués | IBECS | ID: ibc-216852

RESUMEN

Well-being at work scale (WBWS) is a measure widely used in Brazil, composed of three dimen-sions (positive affects, negative affects and expressiveness/fulfillment) aligned with the field’s recent movement of junction of the two classical theoretical bases(hedonic and eudaimonic) that explain this phenomenon. Based on a cross-sectional survey involving 360 Brazilian work-ers, this study aimed to compare different models of interpreting the WBWS (including three one-dimensional proposals -composed by a single factor or second-order factor for WBW as-sessment -and one multidimensional proposal -composed by the three WBW factors singly). Each model was tested through exploratory and confirmatory factor analyzes, and then correla-tion analyzes between the models were run to allow their comparison. We concluded that the interpretation of WBWS from a single indicator is viable and more theoretically appropriate when it is intended to have a more integrated view about well-being at work. (AU)


La Escala de Bienestar en el Trabajo (EBET) es una medida ampliamente utilizada en Brasil, compuesta por tres dimensiones (afecto positivo, afecto negativo y expresividad/realización) alineadas con el movimiento reciente del campo de unión de las dos bases teóricas clásicas (hedónica y eudaimónica) que explican este fenómeno. Basado en una encuesta transversal que involucró a 360 trabajadores brasileños, este estudio tuvo como objetivo comparar diferentes modelos de interpretación de la EBET (incluidas tres propuestas unidimensionales, compuestas por un factor único o factor de segundo orden para la evaluación del BET; y una propuesta multidimensional compuesta por los tres factores BET individualmente). Cada modelo se probó a través de análisis factoriales exploratorios y confirmatorios, y luego se realizaron análisis de correlación entre los modelos para permitir su comparación. Concluimos que la interpretación de la EBET a partir de un solo indicador es viable y teóricamente más adecuada cuando se pre-tende tener una visión más integrada sobre el bienestar en el trabajo. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Satisfacción Personal , Trabajo/psicología , Satisfacción en el Trabajo , Estrategias de Salud , Pesos y Medidas , 16136 , Brasil
10.
Methods Appl Fluoresc ; 11(1)2022 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-36541558

RESUMEN

The resolution achievable with the established super-resolution fluorescence nanoscopy methods, such as STORM or STED, is in general not sufficient to resolve protein complexes or even individual proteins. Recently, minimal photon flux (MINFLUX) nanoscopy has been introduced that combines the strengths of STED and STORM nanoscopy and can achieve a localization precision of less than 5 nm. We established a generally applicable workflow for MINFLUX imaging and applied it for the first time to a bacterial molecular machinein situ, i.e., the injectisome of the enteropathogenY. enterocolitica. We demonstrate with a pore protein of the injectisome that MINFLUX can achieve a resolution down to the single molecule levelin situ. By imaging a sorting platform protein using 3D-MINFLUX, insights into the precise localization and distribution of an injectisome component in a bacterial cell could be accomplished. MINFLUX nanoscopy has the potential to revolutionize super-resolution imaging of dynamic molecular processes in bacteria and eukaryotes.


Asunto(s)
Bacterias , Microscopía Fluorescente/métodos
11.
Mol Psychiatry ; 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36450866

RESUMEN

Postsynaptic scaffold proteins such as Shank, PSD-95, Homer and SAPAP/GKAP family members establish the postsynaptic density of glutamatergic synapses through a dense network of molecular interactions. Mutations in SHANK genes are associated with neurodevelopmental disorders including autism and intellectual disability. However, no SHANK missense mutations have been described which interfere with the key functions of Shank proteins believed to be central for synapse formation, such as GKAP binding via the PDZ domain, or Zn2+-dependent multimerization of the SAM domain. We identify two individuals with a neurodevelopmental disorder carrying de novo missense mutations in SHANK2. The p.G643R variant distorts the binding pocket for GKAP in the Shank2 PDZ domain and prevents interaction with Thr(-2) in the canonical PDZ ligand motif of GKAP. The p.L1800W variant severely delays the kinetics of Zn2+-dependent polymerization of the Shank2-SAM domain. Structural analysis shows that Trp1800 dislodges one histidine crucial for Zn2+ binding. The resulting conformational changes block the stacking of helical polymers of SAM domains into sheets through side-by-side contacts, which is a hallmark of Shank proteins, thereby disrupting the highly cooperative assembly process induced by Zn2+. Both variants reduce the postsynaptic targeting of Shank2 in primary cultured neurons and alter glutamatergic synaptic transmission. Super-resolution microscopy shows that both mutants interfere with the formation of postsynaptic nanoclusters. Our data indicate that both the PDZ- and the SAM-mediated interactions of Shank2 contribute to the compaction of postsynaptic protein complexes into nanoclusters, and that deficiencies in this process interfere with normal brain development in humans.

12.
Antibiotics (Basel) ; 11(10)2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36290065

RESUMEN

Periprosthetic joint infection (PJI) is among the most feared orthopedic complications. Critical questions are whether the infection is completely resolved before reimplantation and what the clinical significance of positive culture is at reimplantation. The aim of this study was to determine whether a correlation exits between culture results at reimplantation after spacer insertion for hip and knee PJI and treatment failure rate. The data of 84 patients who underwent two-stage exchange arthroplasty for hip or knee PJI were reviewed and the results of intraoperative culture at reimplantation were analyzed quantitatively and qualitatively. Correlations were sought between these patterns and treatment outcome. Our data indicate no evidence for a correlation between positive culture at reimplantation and greater risk of treatment failure. Nonetheless, we noted a higher, albeit statistically not significant rate of treatment failure in patients with at least two samples testing positive. The role of microbiology at reimplantation remains unclear, but a positive culture might signal increased risk for subsequent implant failure. Further studies are needed to elucidate the implications of this finding.

13.
Aval. psicol ; 21(3): 273-283, jul.-set. 2022. tab
Artículo en Portugués | LILACS, Index Psicología - Revistas | ID: biblio-1447474

RESUMEN

Conflito trabalho-família é um fenômeno de relevância para a psicologia, uma vez que diz respeito à impossibilidade de conciliar demandas advindas desses dois domínios. Há evidências sobre impactos em domínios da vida dos indivíduos, famílias e organizações. O presente estudo traz evidências adicionais de validade da Escala de Conflito Trabalho-família para o contexto brasileiro, a partir de análises de invariância por sexo e região do país. São apresentadas normas específicas por sexo e região. Participaram da pesquisa 1787 pessoas de três regiões do território brasileiro (sul, sudeste e nordeste). Dentre os participantes, 934 identificaram-se como do sexo feminino (52,3%). Os resultados evidenciaram que o modelo teórico que sustenta a medida não teve ajuste psicométrico favorável em todos os contextos avaliados. Uma versão reduzida com seis itens do instrumento, juntamente com testes de invariância configural, escalar e métrica, tanto por sexo, quanto por região de origem do participante é apresentada. (AU)


Work-family conflict is a phenomenon of relevance to psychology since it concerns the impossibility of reconciling the demands arising from these two domains. Furthermore, there is evidence of impacts in domains for individuals, families, and organizations. The present study provides additional evidence of the validity of the Work-Family Conflict Scale for the Brazilian context, based on analyses of invariance by sex and region of the country, as well as specific norms by sex and region. Participants were 1787 people from three regions of the Brazilian territory (south, southeast, and northeast). Among the participants, 934 identified as female (52.3%). The results showed that the theoretical model that supports the measure did not have a favorable psychometric adjustment in all contexts evaluated. A shorter version with six items of the instrument, along with configural, scalar, and metric invariance tests, both by sex and by the participant's region of origin, is presented. (AU)


El conflicto trabajo-familia es un fenómeno relevante para la psicología, ya que se refiere a la imposibilidad de conciliar las demandas que surgen de estos dos dominios. Hay evidencia de impactos en los dominios para individuos, familias y organizaciones. El presente estudio proporciona evidencias adicionales de la validez de la Escala de Conflicto Trabajo-Familia para el contexto brasileño, a partir de análisis de invarianza por sexo y región del país. Se presentan normas específicas por sexo y región. Participaron de la investigación un total de 1787 personas de tres regiones del territorio brasileño (Sur, Sudeste y Nordeste). Entre los participantes, 934 se identificaron como mujeres (52,3%). Los resultados mostraron que el modelo teórico que respalda la medida no tuvo un ajuste psicométrico favorable en todos los contextos evaluados. Se presenta una versión reducida con seis ítems del instrumento, junto con pruebas de invarianza configuracional, escalar y métrica, tanto por género como por región de origen del participante. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Trabajo/psicología , Familia/psicología , Conflicto Familiar/psicología , Psicometría , Reproducibilidad de los Resultados , Análisis Factorial , Distribución por Sexo
14.
Front Cell Infect Microbiol ; 12: 948151, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35967857

RESUMEN

Staphylococcus epidermidis is a major causative agent of prosthetic joint infections (PJI). The ability to form biofilms supports this highly selective pathogenic potential. In vitro studies essentially relying on phenotypic assays and genetic approaches have provided a detailed picture of the molecular events contributing to biofilm assembly. A major limitation in these studies is the use of synthetic growth media, which significantly differs from the environmental conditions S. epidermidis encounters during host invasion. Building on evidence showing that growth in serum substantially affects S. epidermidis gene expression profiles and phenotypes, the major aim of this study was to develop and characterize a growth medium mimicking synovial fluid, thereby facilitating research addressing specific aspects related to PJI. Using fresh human plasma, a protocol was established allowing for the large-scale production of a medium that by biochemical analysis matches key characteristics of synovial fluid and therefore is referred to as artificial synovial fluid (ASF). By analysis of biofilm-positive, polysaccharide intercellular adhesion (PIA)-producing S. epidermidis 1457 and its isogenic, PIA- and biofilm-negative mutant 1457-M10, evidence is provided that the presence of ASF induces cluster formation in S. epidermidis 1457 and mutant 1457-M10. Consistent with the aggregative properties, both strains formed multilayered biofilms when analyzed by confocal laser scanning microscopy. In parallel to the phenotypic findings, expression analysis after growth in ASF found upregulation of genes encoding for intercellular adhesins (icaA, aap, and embp) as well as atlE, encoding for the major cell wall autolysin being responsible for eDNA release. In contrast, growth in ASF was associated with reduced expression of the master regulator agr. Collectively, these results indicate that ASF induces expression profiles that are able to support intercellular adhesion in both PIA-positive and PIA-negative S. epidermidis. Given the observation that ASF overall induced biofilm formation in a collection of S. epidermidis isolates from PJI, the results strongly support the idea of using growth media mimicking host environments. ASF may play an important role in future studies related to the pathogenesis of S. epidermidis PJI.


Asunto(s)
Staphylococcus epidermidis , Líquido Sinovial , Adhesinas Bacterianas/metabolismo , Biopelículas , Humanos , Polisacáridos Bacterianos/metabolismo , Staphylococcus epidermidis/genética , Líquido Sinovial/metabolismo
15.
RNA Biol ; 19(1): 877-884, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35796440

RESUMEN

Stress granules (SGs) are membrane-less condensates composed of RNA and protein that assemble in response to stress stimuli and disassemble when stress is lifted. Both assembly and disassembly are tightly controlled processes, yet, it remains elusive whether mRNAs in SGs completely recover for translation following stress relief. Using RNA-seq of translating fractions in human cell line, we found that higher fraction of the m6A-modified mRNAs recovered for translation compared to unmodified mRNAs, i.e. 95% vs 84%, respectively. Considering structural mRNA analysis, we found that the m6A modification enhances structuring at nucleotides in its close vicinity. Our results suggest that SG-sequestered mRNAs disassemble nearly completely from SGs and the m6A modification may display some advantage to the mRNAs in their recovery for translation likely by m6A-driven structural stabilization.


Asunto(s)
Gránulos Citoplasmáticos , Gránulos de Estrés , Línea Celular , Gránulos Citoplasmáticos/metabolismo , Humanos , ARN/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
16.
Nat Commun ; 13(1): 4192, 2022 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-35858909

RESUMEN

Dissociation of hyper-phosphorylated Tau from neuronal microtubules and its pathological aggregates, are hallmarks in the etiology of tauopathies. The Tau-microtubule interface is subject to polyglutamylation, a reversible posttranslational modification, increasing negative charge at tubulin C-terminal tails. Here, we asked whether tubulin polyglutamylation may contribute to Tau pathology in vivo. Since polyglutamylases modify various proteins other than tubulin, we generated a knock-in mouse carrying gene mutations to abolish Tuba4a polyglutamylation in a substrate-specific manner. We found that Tuba4a lacking C-terminal polyglutamylation prevents the binding of Tau and GSK3 kinase to neuronal microtubules, thereby strongly reducing phospho-Tau levels. Notably, crossbreeding of the Tuba4a knock-in mouse with the hTau tauopathy model, expressing a human Tau transgene, reversed hyper-phosphorylation and oligomerization of Tau and normalized microglia activation in brain. Our data highlight tubulin polyglutamylation as a potential therapeutic strategy in fighting tauopathies.


Asunto(s)
Tauopatías , Tubulina (Proteína) , Animales , Glucógeno Sintasa Quinasa 3/metabolismo , Humanos , Ratones , Microglía/metabolismo , Microtúbulos/metabolismo , Fosforilación , Tauopatías/metabolismo , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo
17.
BMC Surg ; 22(1): 68, 2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35216567

RESUMEN

BACKGROUND: Periprosthetic hip infections with severe proximal femoral bone loss may require the use of limb salvage techniques, but no agreement exists in literature regarding the most effective treatment. Aim of this study is to analyze the infection eradication rate and implant survival at medium-term follow-up in patients treated with megaprostheses for periprosthetic hip infections with severe bone loss. METHODS: Twenty-one consecutive patients were retrospectively reviewed at a mean 64-month follow-up (24-120). Functional and pain scores, microbiological, radiological and intraoperative findings were registered. Kaplan Meier survival analysis and log rank test were used for infection free survival and implant survival analyses. RESULTS: The infection eradication rate was 90.5%, with an infection free survival of 95.2% at 2 years (95%CI 70.7-99.3) and 89.6%(95%CI 64.3-97.3) at 5 years. Only two patients required major implant revisions for aseptic implant loosening. The most frequent complication was dislocation (38.1%). The major revision-free survival of implants was 95.2% (95%CI 70.7-99.3) at 2 years and 89.6% (95%CI 64.3-97.3) at 5 years. The overall implant survival was 83.35% (CI95% 50.7-93.94) at 2 and 5 years. Subgroup analyses (cemented versus cementless MPs, coated versus uncoated MPs) revealed no significant differences at log rank test, but its reliability was limited by the small number of patients included. CONCLUSIONS: Proximal femoral arthroplasty is useful to treat periprosthetic hip infections with severe bone loss, providing good functional results with high infection eradication rates and rare major revisions at medium-term follow-up. No conclusions can be drawn on the role of cement and coatings.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/métodos , Estudios de Seguimiento , Prótesis de Cadera/efectos adversos , Humanos , Diseño de Prótesis , Falla de Prótesis , Reoperación/efectos adversos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Resultado del Tratamiento
18.
Sci Rep ; 12(1): 902, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35042901

RESUMEN

Shank proteins are major scaffolds of the postsynaptic density of excitatory synapses. Mutations in SHANK genes are associated with autism and intellectual disability. The effects of missense mutations on Shank3 function, and therefore the pathomechanisms are unclear. Several missense mutations in SHANK3 affect the N-terminal region, consisting of the Shank/ProSAP N-terminal (SPN) domain and a set of Ankyrin (Ank) repeats. Here we identify a novel SHANK3 missense mutation (p.L270M) in the Ankyrin repeats in patients with an ADHD-like phenotype. We functionally analysed this and a series of other mutations, using biochemical and biophysical techniques. We observe two major effects: (1) a loss of binding to δ-catenin (e.g. in the p.L270M variant), and (2) interference with the intramolecular interaction between N-terminal SPN domain and the Ank repeats. This also interferes with binding to the α-subunit of the calcium-/calmodulin dependent kinase II (αCaMKII), and appears to be associated with a more severe neurodevelopmental pathology.


Asunto(s)
Sinapsis
19.
Psicol. ciênc. prof ; 42: e235842, 2022.
Artículo en Portugués | LILACS, Index Psicología - Revistas | ID: biblio-1360633

RESUMEN

O estágio é um espaço de vivências de integração ensino-trabalho, que pode viabilizar a concretização de conhecimentos em ações profissionais e possibilitar ao estudante trabalhar com pessoas de diferentes identidades. Diante dessa diversidade, a experiência de inclusão no trabalho se relaciona com a percepção dos indivíduos quanto a sua aceitação, respeito e valorização, em função de sua identidade individual e grupal. Nesse sentido, este estudo objetivou compreender a experiência psicológica de inclusão entre estagiárias de Psicologia. Utilizou-se uma abordagem qualitativa, por meio da realização de entrevistas narrativas com 15 estudantes de Psicologia que estagiavam em equipes multiprofissionais de saúde, com idades entre 23 e 57 anos; dentre eles, 14 eram mulheres e 10 eram autodeclaradas negras. Mediante o uso de categorias temáticas, as narrativas foram analisadas, buscando compreender os sentidos que as experiências tiveram para as entrevistadas. A experiência psicológica de inclusão foi vinculada à percepção de pertencimento à equipe e de acesso às informações e aos recursos necessários para o desenvolvimento do trabalho. Por outro lado, as estagiárias expressaram que, em algumas situações, não sentiam interação e comunicação construtivas com médicos e trabalhadores da enfermagem. Os resultados afirmaram a importância dos estágios curriculares como dispositivos de inclusão no mundo do trabalho, reiterando que a diversidade abrange elementos como experiência no trabalho e categoria profissional. Entende-se que esses conhecimentos podem promover importantes discussões e, assim, fundamentar a elaboração de políticas e práticas organizacionais mais inclusivas para lidar com uma força de trabalho diversa.(AU)


The internship is a space for teaching-work integration experiences, which can enable knowledge to materialize in professional actions and enable the student to work with people of different identities. Given this diversity, the experience of inclusion at work relates to the perception of individuals regarding their acceptance, respect, and appreciation, according to their individual and group identity. In this sense, our study aimed to understand the psychological experience of inclusion among psychology interns. A qualitative approach was used, with narrative interviews with 15 Psychology students interning with multiprofessional health teams, aged between 23 and 57 years old; among them, 14 women and 10 self-declared black. By using thematic categories, we analyzed the narratives, seeking to understand the meanings that the experiences had for the interviewees. The psychological experience of inclusion was linked to the perception of belonging to the team and of access to the information and resources necessary for the development of the work. On the other hand, the interns expressed that, in some situations, they felt no constructive interaction and communication with nursing workers and doctors. The results affirmed the importance of curricular internships as devices for inclusion in the world of work, reiterating that diversity includes elements such as work experience and professional category. We understand that this knowledge can promote important discussions and, thus, support the development of more inclusive organizational policies and practices to deal with a diverse workforce.(AU)


La pasantía es un espacio para experiencias de integración trabajo-enseñanza, que puede permitir la concreción del conocimiento en acciones profesionales y que el alumno trabaje con personas de diferentes identidades. En vista de esta diversidad, la experiencia de inclusión en el trabajo está relacionada con la percepción de los individuos con respecto a su aceptación, respeto y apreciación, de acuerdo con su identidad individual y grupal. En este sentido, este estudio tuvo como objetivo comprender la experiencia psicológica de inclusión entre las pasantes de Psicología. Se utilizó el enfoque cualitativo, realizando entrevistas narrativas con 15 estudiantes de psicología, que eran pasantes en equipos de salud multiprofesionales, con edades entre 23 y 57 años, de las cuales 14 eran mujeres y 10 autodeclararon negras. Mediante el uso de categorías temáticas, se analizaron las narrativas, buscando comprender los significados que las experiencias tuvieron para las entrevistadas. La experiencia psicológica de inclusión estuvo vinculada a la percepción de pertenencia al equipo y al acceso a la información y los recursos necesarios para el desarrollo del trabajo. Por otro lado, las pasantes expresaron que, en algunas situaciones, no sentían una interacción constructiva y comunicación con los trabajadores de enfermería y los médicos. Los resultados afirmaron la importancia de las pasantías curriculares como dispositivos para la inclusión en el mundo laboral, reiterando que la diversidad incluye elementos como la experiencia laboral y la categoría profesional. Se entiende que este conocimiento puede promover debates importantes y, por lo tanto, apoyar el desarrollo de políticas y prácticas organizacionales más inclusivas para tratarse con una fuerza laboral diversa.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Adulto Joven , Grupo de Atención al Paciente , Psicología , Apoyo a la Formación Profesional , Inclusión Social , Relaciones Interpersonales , Apoyo a la Formación Profesional , Trabajo , Política Organizacional , Crecimiento y Desarrollo , Grupos Profesionales
20.
Cancers (Basel) ; 13(15)2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-34359774

RESUMEN

Keratins are the main identification markers of circulating tumor cells (CTCs); however, whether their deregulation is associated with the metastatic process is largely unknown. Previously we have shown by in silico analysis that keratin 16 (KRT16) mRNA upregulation might be associated with more aggressive cancer. Therefore, in this study, we investigated the biological role and the clinical relevance of K16 in metastatic breast cancer. By performing RT-qPCR, western blot, and immunocytochemistry, we investigated the expression patterns of K16 in metastatic breast cancer cell lines and evaluated the clinical relevance of K16 expression in CTCs of 20 metastatic breast cancer patients. High K16 protein expression was associated with an intermediate mesenchymal phenotype. Functional studies showed that K16 has a regulatory effect on EMT and overexpression of K16 significantly enhanced cell motility (p < 0.001). In metastatic breast cancer patients, 64.7% of the detected CTCs expressed K16, which was associated with shorter relapse-free survival (p = 0.0042). Our findings imply that K16 is a metastasis-associated protein that promotes EMT and acts as a positive regulator of cellular motility. Furthermore, determining K16 status in CTCs provides prognostic information that helps to identify patients whose tumors are more prone to metastasize.

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