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1.
Mol Cell ; 84(4): 687-701.e7, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38266641

RESUMEN

Molecular chaperones are critical for protein homeostasis and are implicated in several human pathologies such as neurodegeneration and cancer. While the binding of chaperones to nascent and misfolded proteins has been studied in great detail, the direct interaction between chaperones and RNA has not been systematically investigated. Here, we provide the evidence for widespread interaction between chaperones and RNA in human cells. We show that the major chaperone heat shock protein 70 (HSP70) binds to non-coding RNA transcribed by RNA polymerase III (RNA Pol III) such as tRNA and 5S rRNA. Global chromatin profiling revealed that HSP70 binds genomic sites of transcription by RNA Pol III. Detailed biochemical analyses showed that HSP70 alleviates the inhibitory effect of cognate tRNA transcript on tRNA gene transcription. Thus, our study uncovers an unexpected role of HSP70-RNA interaction in the biogenesis of a specific class of non-coding RNA with wider implications in cancer therapeutics.


Asunto(s)
Proteínas HSP70 de Choque Térmico , Neoplasias , Humanos , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Chaperonas Moleculares/metabolismo , ARN , ARN Polimerasa III/genética , ARN Polimerasa III/metabolismo , ARN de Transferencia/genética , ARN no Traducido/genética
2.
Mol Cell ; 81(5): 1013-1026.e11, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33548202

RESUMEN

In response to stress, human cells coordinately downregulate transcription and translation of housekeeping genes. To downregulate transcription, the negative elongation factor (NELF) is recruited to gene promoters impairing RNA polymerase II elongation. Here we report that NELF rapidly forms nuclear condensates upon stress in human cells. Condensate formation requires NELF dephosphorylation and SUMOylation induced by stress. The intrinsically disordered region (IDR) in NELFA is necessary for nuclear NELF condensation and can be functionally replaced by the IDR of FUS or EWSR1 protein. We find that biomolecular condensation facilitates enhanced recruitment of NELF to promoters upon stress to drive transcriptional downregulation. Importantly, NELF condensation is required for cellular viability under stressful conditions. We propose that stress-induced NELF condensates reported here are nuclear counterparts of cytosolic stress granules. These two stress-inducible condensates may drive the coordinated downregulation of transcription and translation, likely forming a critical node of the stress survival strategy.


Asunto(s)
Respuesta al Choque Térmico/genética , Proteínas Intrínsecamente Desordenadas/genética , Procesamiento Proteico-Postraduccional , ARN Polimerasa II/genética , Transcripción Genética , Factores de Elongación Transcripcional/genética , Aminoaciltransferasas/genética , Aminoaciltransferasas/metabolismo , Cromatina/química , Cromatina/metabolismo , Células Clonales , Quinasa 9 Dependiente de la Ciclina/genética , Quinasa 9 Dependiente de la Ciclina/metabolismo , Genes Reporteros , Células HEK293 , Células HeLa , Humanos , Proteínas Intrínsecamente Desordenadas/química , Proteínas Intrínsecamente Desordenadas/metabolismo , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Fosforilación , Factor B de Elongación Transcripcional Positiva/genética , Factor B de Elongación Transcripcional Positiva/metabolismo , Regiones Promotoras Genéticas , ARN Polimerasa II/metabolismo , Transducción de Señal , Estrés Fisiológico , Sumoilación , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Factores de Elongación Transcripcional/química , Factores de Elongación Transcripcional/metabolismo , Proteína Fluorescente Roja
3.
Proc Natl Acad Sci U S A ; 121(6): e2305944121, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38252845

RESUMEN

Protected areas are of paramount relevance to conserving wildlife and ecosystem contributions to people. Yet, their conservation success is increasingly threatened by human activities including habitat loss, climate change, pollution, and species overexploitation. Thus, understanding the underlying and proximate drivers of anthropogenic threats is urgently needed to improve protected areas' effectiveness, especially in the biodiversity-rich tropics. We addressed this issue by analyzing expert-provided data on long-term biodiversity change (last three decades) over 14 biosphere reserves from the Mesoamerican Biodiversity Hotspot. Using multivariate analyses and structural equation modeling, we tested the influence of major socioeconomic drivers (demographic, economic, and political factors), spatial indicators of human activities (agriculture expansion and road extension), and forest landscape modifications (forest loss and isolation) as drivers of biodiversity change. We uncovered a significant proliferation of disturbance-tolerant guilds and the loss or decline of disturbance-sensitive guilds within reserves causing a "winner and loser" species replacement over time. Guild change was directly related to forest spatial changes promoted by the expansion of agriculture and roads within reserves. High human population density and low nonfarming occupation were identified as the main underlying drivers of biodiversity change. Our findings suggest that to mitigate anthropogenic threats to biodiversity within biosphere reserves, fostering human population well-being via sustainable, nonfarming livelihood opportunities around reserves is imperative.


Asunto(s)
Biodiversidad , Ecosistema , Humanos , Animales , Agricultura , Animales Salvajes , Cambio Climático
4.
EMBO J ; 40(14): e106355, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34128550

RESUMEN

DNA interstrand crosslinks (ICLs) induced by endogenous aldehydes or chemotherapeutic agents interfere with essential processes such as replication and transcription. ICL recognition and repair by the Fanconi Anemia pathway require the formation of an X-shaped DNA structure that may arise from convergence of two replication forks at the crosslink or traversing of the lesion by a single replication fork. Here, we report that ICL traverse strictly requires DNA repriming events downstream of the lesion, which are carried out by PrimPol, the second primase-polymerase identified in mammalian cells after Polα/Primase. The recruitment of PrimPol to the vicinity of ICLs depends on its interaction with RPA, but not on FANCM translocase or the BLM/TOP3A/RMI1-2 (BTR) complex that also participate in ICL traverse. Genetic ablation of PRIMPOL makes cells more dependent on the fork convergence mechanism to initiate ICL repair, and PRIMPOL KO cells and mice display hypersensitivity to ICL-inducing drugs. These results open the possibility of targeting PrimPol activity to enhance the efficacy of chemotherapy based on DNA crosslinking agents.


Asunto(s)
ADN Primasa/genética , Replicación del ADN/genética , ADN Polimerasa Dirigida por ADN/genética , ADN/genética , Enzimas Multifuncionales/genética , Animales , ADN Helicasas/genética , Reparación del ADN/genética , Femenino , Humanos , Masculino , Mamíferos/genética , Ratones
5.
Eur J Immunol ; : e2350716, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38837757

RESUMEN

Immune mediators affect multiple biological functions of intestinal epithelial cells (IECs) and, like Paneth and Paneth-like cells, play an important role in intestinal epithelial homeostasis. IFN-γ a prototypical proinflammatory cytokine disrupts intestinal epithelial homeostasis. However, the mechanism underlying the process remains unknown. In this study, using in vivo and in vitro models we demonstrate that IFN-γ is spontaneously secreted in the small intestine. Furthermore, we observed that this cytokine stimulates mitochondrial activity, ROS production, and Paneth and Paneth-like cell secretion. Paneth and Paneth-like secretion downstream of IFN-γ, as identified here, is mTORC1 and necroptosis-dependent. Thus, our findings revealed that the pleiotropic function of IFN-γ also includes the regulation of Paneth cell function in the homeostatic gut.

6.
EMBO Rep ; 24(11): e57571, 2023 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-37795769

RESUMEN

The peptide toxin candidalysin, secreted by Candida albicans hyphae, promotes stimulation of neutrophil extracellular traps (NETs). However, candidalysin alone triggers a distinct mechanism for NET-like structures (NLS), which are more compact and less fibrous than canonical NETs. Candidalysin activates NADPH oxidase and calcium influx, with both processes contributing to morphological changes in neutrophils resulting in NLS formation. NLS are induced by leucotoxic hypercitrullination, which is governed by calcium-induced protein arginine deaminase 4 activation and initiation of intracellular signalling events in a dose- and time-dependent manner. However, activation of signalling by candidalysin does not suffice to trigger downstream events essential for NET formation, as demonstrated by lack of lamin A/C phosphorylation, an event required for activation of cyclin-dependent kinases that are crucial for NET release. Candidalysin-triggered NLS demonstrate anti-Candida activity, which is resistant to nuclease treatment and dependent on the deprivation of Zn2+ . This study reveals that C. albicans hyphae releasing candidalysin concurrently trigger canonical NETs and NLS, which together form a fibrous sticky network that entangles C. albicans hyphae and efficiently inhibits their growth.


Asunto(s)
Candida albicans , Trampas Extracelulares , Candida albicans/metabolismo , Trampas Extracelulares/metabolismo , Calcio/metabolismo , Proteínas Fúngicas/metabolismo
7.
Kidney Int ; 105(3): 430-433, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38388140

RESUMEN

The study by Chen et al. is the first to apply the revolutionary genetic engineering tool, base editing, in a rat model for the treatment of primary hyperoxaluria type 1, a disease that originates in the liver but in which the kidney is the main organ affected. This commentary contextualizes and describes the gene-editing technology applied by the authors, provides an interpretation and opinion of their results, and indicates possible future applications.


Asunto(s)
Edición Génica , Enfermedades Renales , Ratas , Animales , Edición Génica/métodos , Sistemas CRISPR-Cas , Ingeniería Genética , Enfermedades Renales/genética , Enfermedades Renales/terapia , Riñón
8.
Mol Microbiol ; 120(2): 178-193, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37392318

RESUMEN

Serine protease autotransporters of Enterobacteriaceae (SPATE) constitute a superfamily of virulence factors, resembling the trypsin-like superfamily of serine proteases. SPATEs accomplish multiple functions associated to disease development of their hosts, which could be the consequence of SPATE cleavage of host cell components. SPATEs have been divided into class-1 and class-2 based on structural differences and biological effects, including similar substrate specificity, cytotoxic effects on cultured cells, and enterotoxin activity on intestinal tissues for class-1 SPATEs, whereas most class-2 SPATEs exhibit a lectin-like activity with a predilection to degrade a variety of mucins, including leukocyte surface O-glycoproteins and soluble host proteins, resulting in mucosal colonization and immune modulation. In this review, the structure of class-1 and class-2 are analyzed, making emphasis on their putative functional subdomains as well as a description of their function is provided, including prototypical mechanism of action.


Asunto(s)
Proteínas de Escherichia coli , Serina Proteasas , Serina Proteasas/metabolismo , Enterobacteriaceae/genética , Enterobacteriaceae/metabolismo , Sistemas de Secreción Tipo V , Serina Endopeptidasas/genética , Serina Endopeptidasas/metabolismo , Células Cultivadas , Glicoproteínas de Membrana
9.
J Transl Med ; 22(1): 526, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38822352

RESUMEN

BACKGROUND: Neutrophils are granulocytes with essential antimicrobial effector functions and short lifespans. During infection or sterile inflammation, emergency granulopoiesis leads to release of immature neutrophils from the bone marrow, serving to boost circulating neutrophil counts. Steady state and emergency granulopoiesis are incompletely understood, partly due to a lack of genetically amenable models of neutrophil development. METHODS: We optimised a method for ex vivo production of human neutrophils from CD34+ haematopoietic progenitors. Using flow cytometry, we phenotypically compared cultured neutrophils with native neutrophils from donors experiencing emergency granulopoiesis, and steady state neutrophils from non-challenged donors. We carry out functional and proteomic characterisation of cultured neutrophils and establish genome editing of progenitors. RESULTS: We obtain high yields of ex vivo cultured neutrophils, which phenotypically resemble immature neutrophils released into the circulation during emergency granulopoiesis. Cultured neutrophils have similar rates of ROS production and bacterial killing but altered degranulation, cytokine release and antifungal activity compared to mature neutrophils isolated from peripheral blood. These differences are likely due to incomplete synthesis of granule proteins, as demonstrated by proteomic analysis. CONCLUSION: Ex vivo cultured neutrophils are genetically tractable via genome editing of precursors and provide a powerful model system for investigating the properties and behaviour of immature neutrophils.


Asunto(s)
Antígenos CD34 , Neutrófilos , Humanos , Neutrófilos/metabolismo , Neutrófilos/citología , Antígenos CD34/metabolismo , Células Cultivadas , Especies Reactivas de Oxígeno/metabolismo , Proteómica , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/citología , Edición Génica , Degranulación de la Célula , Células Madre/metabolismo , Células Madre/citología , Citocinas/metabolismo , Fenotipo
10.
Microb Pathog ; 192: 106706, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38763316

RESUMEN

Mannheimiahaemolytica is an opportunistic agent of the respiratory tract of bovines, a member of the Pasteurellaceae family, and the causal agent of fibrinous pleuropneumonia. This bacterium possesses different virulence factors, allowing it to colonize and infect its host. The present work describes the isolation and characterization of a serine protease secreted by M. haemolytica serotype 1. This protease was isolated from M. haemolytica cultured media by precipitation with 50 % methanol and ion exchange chromatography on DEAE-cellulose. It is a 70-kDa protease able to degrade sheep and bovine fibrinogen or porcine gelatin but not bovine IgG, hemoglobin, or casein. Mass spectrometric analysis indicates its identity with protease IV of M. haemolytica. The proteolytic activity was active between pH 5 and 9, with an optimal pH of 8. It was stable at 50 °C for 10 min but inactivated at 60 °C. The sera of bovines with chronic or acute pneumonia recognized this protease. Still, it showed no cross-reactivity with rabbit hyperimmune serum against the secreted metalloprotease from Actinobacilluspleuropneumoniae, another member of the Pasteurellaceae family. M. haemolytica secreted proteases could contribute to the pathogenesis of this bacterium through fibrinogen degradation, a characteristic of this fibrinous pleuropneumonia.


Asunto(s)
Fibrinógeno , Mannheimia haemolytica , Serina Proteasas , Animales , Mannheimia haemolytica/enzimología , Ovinos , Bovinos , Fibrinógeno/metabolismo , Concentración de Iones de Hidrógeno , Serina Proteasas/metabolismo , Serina Proteasas/aislamiento & purificación , Temperatura , Proteolisis , Peso Molecular , Gelatina/metabolismo , Estabilidad de Enzimas , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/aislamiento & purificación , Espectrometría de Masas , Cromatografía por Intercambio Iónico , Porcinos , Factores de Virulencia/metabolismo , Factores de Virulencia/aislamiento & purificación
11.
Transfusion ; 64(4): 572-577, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38380832

RESUMEN

INTRODUCTION: Sanquin donor medicine department is informed when donations or their components are rejected. This can occur isolated or frequently. It is undesirable because the donations cannot be used and there may be an underlying medical cause. Based on regional approaches, a uniform procedure was developed. METHODS: Information about whole blood, plasma- plateletpheresis donations from which one or more components were rejected for filtration time (>2 h), hemolysis or clots were extracted from blood bank information system. After rejection of two successive components or donations or total ≥3 the donor is contacted. Depending on the medical history and investigation by the family doctor, the donor carrier is re-evaluated. We looked for the causes of the discarded products and performed a survey among blood services regarding polices with discarded products. RESULTS: One or more components from 1742 of about 2.2 million successful donations (0.08%) were rejected. The highest percentage of rejection was seen in plateletpheresis (1.5%), all for clots. No underlying medical causes were found. 24 whole blood donors were found to have sickle cell trait (SCT) and were permanently deferred. The policies for follow-up after discarded products or acceptance of SCT donors vary between the 16 blood banks. Six organizations do not follow-up donors and seven accept SCT for blood or plasma donation. CONCLUSION: Informing donors with repeated discarded products avoids the non-use of donations. Causes of repeated discarded products can be found by follow-up of donors. The results of the survey indicate a large discrepancy in policies applied worldwide.


Asunto(s)
Hemólisis , Plaquetoferesis , Humanos , Estudios de Seguimiento , Donantes de Sangre , Bancos de Sangre
12.
Transpl Int ; 37: 12791, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38681973

RESUMEN

Intensive Care to facilitate Organ Donation (ICOD) consists of the initiation or continuation of intensive care measures in patients with a devastating brain injury (DBI) in whom curative treatment is deemed futile and death by neurological criteria (DNC) is foreseen, to incorporate organ donation into their end-of-life plans. In this study we evaluate the outcomes of patients subject to ICOD and identify radiological and clinical factors associated with progression to DNC. In this first prospective multicenter study we tested by multivariate regression the association of clinical and radiological severity features with progression to DNC. Of the 194 patients, 144 (74.2%) patients fulfilled DNC after a median of 25 h (95% IQR: 17-44) from ICOD onset. Two patients (1%) shifted from ICOD to curative treatment, both were alive at discharge. Factors associated with progression to DNC included: age below 70 years, clinical score consistent with severe brain injury, instability, intracranial hemorrhage, midline shift ≥5 mm and certain types of brain herniation. Overall 151 (77.8%) patients progressed to organ donation. Based on these results, we conclude that ICOD is a beneficial and efficient practice that can contribute to the pool of deceased donors.


Asunto(s)
Cuidados Críticos , Obtención de Tejidos y Órganos , Humanos , Estudios Prospectivos , Masculino , Femenino , Obtención de Tejidos y Órganos/métodos , Persona de Mediana Edad , Anciano , España , Adulto , Lesiones Encefálicas , Muerte Encefálica , Unidades de Cuidados Intensivos
13.
Clin Chem Lab Med ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38965828

RESUMEN

There is a need for standards for generation and reporting of Biological Variation (BV) reference data. The absence of standards affects the quality and transportability of BV data, compromising important clinical applications. To address this issue, international expert groups under the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) have developed an online resource (https://tinyurl.com/bvmindmap) in the form of an interactive mind map that serves as a guideline for researchers planning, performing and reporting BV studies. The mind map addresses study design, data analysis, and reporting criteria, providing embedded links to relevant references and resources. It also incorporates a checklist approach, identifying a Minimum Data Set (MDS) to enable the transportability of BV data and incorporates the Biological Variation Data Critical Appraisal Checklist (BIVAC) to assess study quality. The mind map is open to access and is disseminated through the EFLM BV Database website, promoting accessibility and compliance to a reporting standard, thereby providing a tool to be used to ensure data quality, consistency, and comparability of BV data. Thus, comparable to the STARD initiative for diagnostic accuracy studies, the mind map introduces a Standard for Reporting Biological Variation Data Studies (STARBIV), which can enhance the reporting quality of BV studies, foster user confidence, provide better decision support, and be used as a tool for critical appraisal. Ongoing refinement is expected to adapt to emerging methodologies, ensuring a positive trajectory toward improving the validity and applicability of BV data in clinical practice.

14.
Radiographics ; 44(6): e230182, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38781089

RESUMEN

Renal transplant is the first-line treatment of end-stage renal disease. The increasing number of transplants performed every year has led to a larger population of transplant patients. Complications may arise during the perioperative and postoperative periods, and imaging plays a key role in this scenario. Contrast-enhanced US (CEUS) is a safe tool that adds additional value to US. Contrast agents are usually administered intravenously, but urinary tract anatomy and complications such as stenosis or leak can be studied using intracavitary administration of contrast agents. Assessment of the graft and iliac vessels with CEUS is particularly helpful in identifying vascular and parenchymal complications, such as arterial or venous thrombosis and stenosis, acute tubular injury, or cortical necrosis, which can lead to graft loss. Furthermore, infectious and malignant graft involvement can be accurately studied with CEUS, which can help in detection of renal abscesses and in the differentiation between benign and malignant disease. CEUS is also useful in interventional procedures, helping to guide percutaneous aspiration of collections with better delimitation of the graft boundaries and to guide renal graft biopsies by avoiding avascular areas. Potential postprocedural vascular complications, such as pseudoaneurysm, arteriovenous fistula, or active bleeding, are identified with CEUS. In addition, newer quantification tools such as CEUS perfusion are promising, but further studies are needed to approve its use for clinical purposes. ©RSNA, 2024 Supplemental material is available for this article.


Asunto(s)
Medios de Contraste , Trasplante de Riñón , Complicaciones Posoperatorias , Ultrasonografía , Humanos , Trasplante de Riñón/efectos adversos , Complicaciones Posoperatorias/diagnóstico por imagen , Ultrasonografía/métodos , Fallo Renal Crónico/diagnóstico por imagen , Fallo Renal Crónico/terapia , Fallo Renal Crónico/cirugía
15.
BMC Public Health ; 24(1): 1501, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38840230

RESUMEN

BACKGROUND: This study aims to evaluate healthcare systems and pandemic responses in relation to marginalized and vulnerable groups, identify populations requiring urgent care, and assess the differential impacts on their health during the pandemic. METHODS: Data were collected by the Asia-Pacific Observatory on Health Systems and Policies (APO)-National University of Singapore and APO-International Health Policy Program consortium members: Korea, Indonesia, Philippines, and Singapore. Data were collected through a combination of semi-structured interviews, policy document reviews, and analysis of secondary data. RESULTS: Our findings reveal that the pandemic exacerbated existing health disparities, particularly affecting older adults, women, and children. Additionally, the study identified LGBTI individuals, healthcare workers, slum dwellers, and migrant workers as groups that faced particularly severe challenges during the pandemic. LGBTI individuals encountered heightened discrimination and limited access to health services tailored to their needs. Healthcare workers suffered from immense stress and risk due to prolonged exposure to the virus and critical working conditions. Slum dwellers struggled with healthcare access and social distancing due to high population density and inadequate sanitation. Migrant workers were particularly hard hit by high risks of virus transmission and stringent, often discriminatory, isolation measures that compounded their vulnerability. The study highlights the variation in the extent and nature of vulnerabilities, which were influenced by each country's specific social environment and healthcare infrastructure. It was observed that public health interventions often lacked the specificity required to effectively address the needs of all vulnerable groups, suggesting a gap in policy and implementation. CONCLUSIONS: The study underscores that vulnerabilities vary greatly depending on the social environment and context of each country, affecting the degree and types of vulnerable groups. It is critical that measures to ensure universal health coverage and equal accessibility to healthcare are specifically designed to address the needs of the most vulnerable. Despite commonalities among groups across different societies, these interventions must be adapted to reflect the unique characteristics of each group within their specific social contexts to effectively mitigate the impact of health disparities.


Asunto(s)
COVID-19 , Poblaciones Vulnerables , Humanos , COVID-19/epidemiología , Femenino , Masculino , Adulto , Filipinas/epidemiología , Persona de Mediana Edad , Accesibilidad a los Servicios de Salud , Atención a la Salud/organización & administración , Singapur/epidemiología , Pandemias , República de Corea/epidemiología , Disparidades en el Estado de Salud , Indonesia/epidemiología , Anciano , Medio Social , Adulto Joven , Disparidades en Atención de Salud
16.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-34301865

RESUMEN

In mammals, the KRAS locus encodes two protein isoforms, KRAS4A and KRAS4B, which differ only in their C terminus via alternative splicing of distinct fourth exons. Previous studies have shown that whereas KRAS expression is essential for mouse development, the KRAS4A isoform is expendable. Here, we have generated a mouse strain that carries a terminator codon in exon 4B that leads to the expression of an unstable KRAS4B154 truncated polypeptide, hence resulting in a bona fide Kras4B-null allele. In contrast, this terminator codon leaves expression of the KRAS4A isoform unaffected. Mice selectively lacking KRAS4B expression developed to term but died perinatally because of hypertrabeculation of the ventricular wall, a defect reminiscent of that observed in embryos lacking the Kras locus. Mouse embryonic fibroblasts (MEFs) obtained from Kras4B-/- embryos proliferated less than did wild-type MEFs, because of limited expression of KRAS4A, a defect that can be compensated for by ectopic expression of this isoform. Introduction of the same terminator codon into a KrasFSFG12V allele allowed expression of an endogenous KRAS4AG12V oncogenic isoform in the absence of KRAS4B. Exposure of Kras+/FSF4AG12V4B- mice to Adeno-FLPo particles induced lung tumors with complete penetrance, albeit with increased latencies as compared with control Kras+/FSFG12V animals. Moreover, a significant percentage of these mice developed proximal metastasis, a feature seldom observed in mice expressing both mutant isoforms. These results illustrate that expression of the KRAS4AG12V mutant isoform is sufficient to induce lung tumors, thus suggesting that selective targeting of the KRAS4BG12V oncoprotein may not have significant therapeutic consequences.


Asunto(s)
Adenocarcinoma del Pulmón/secundario , Neoplasias Pulmonares/patología , Proteínas Proto-Oncogénicas p21(ras)/fisiología , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/metabolismo , Animales , Apoptosis , Proliferación Celular , Femenino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación , Isoformas de Proteínas , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Int J Mol Sci ; 25(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38474060

RESUMEN

The pathophysiology of nonketotic hyperglycinemia (NKH), a rare neuro-metabolic disorder associated with severe brain malformations and life-threatening neurological manifestations, remains incompletely understood. Therefore, a valid human neural model is essential. We aimed to investigate the impact of GLDC gene variants, which cause NKH, on cellular fitness during the differentiation process of human induced pluripotent stem cells (iPSCs) into iPSC-derived astrocytes and to identify sustainable mechanisms capable of overcoming GLDC deficiency. We developed the GLDC27-FiPS4F-1 line and performed metabolomic, mRNA abundance, and protein analyses. This study showed that although GLDC27-FiPS4F-1 maintained the parental genetic profile, it underwent a metabolic switch to an altered serine-glycine-one-carbon metabolism with a coordinated cell growth and cell cycle proliferation response. We then differentiated the iPSCs into neural progenitor cells (NPCs) and astrocyte-lineage cells. Our analysis showed that GLDC-deficient NPCs had shifted towards a more heterogeneous astrocyte lineage with increased expression of the radial glial markers GFAP and GLAST and the neuronal markers MAP2 and NeuN. In addition, we detected changes in other genes related to serine and glycine metabolism and transport, all consistent with the need to maintain glycine at physiological levels. These findings improve our understanding of the pathology of nonketotic hyperglycinemia and offer new perspectives for therapeutic options.


Asunto(s)
Hiperglicinemia no Cetósica , Células Madre Pluripotentes Inducidas , Humanos , Hiperglicinemia no Cetósica/genética , Hiperglicinemia no Cetósica/patología , Glicina-Deshidrogenasa (Descarboxilante)/genética , Astrocitos/patología , Células Madre Pluripotentes Inducidas/patología , Glicina , Serina
18.
Artículo en Inglés | MEDLINE | ID: mdl-38995491

RESUMEN

There are few studies exploring intake diagnostic characteristics as predictors of change in integrative naturalistic settings. The aim of this study is to explore baseline variables at the intake process and establish the predictive value of the individual trajectories of the patients. We recruited 259 patients undergoing an integrative psychotherapy network of psychotherapists from Buenos Aires, Argentina. Every therapist completed the intake form of each patient involved in the routine outcome monitoring. Thereafter step-wise regressions based on forward selection strategies were used, in order to identify meaningful baseline predictors of patients' clinical evolution, derived from the intake process. The selected predictors were social support network, subjective distress, the initial measure of clinical distress, unemployment, sociocultural status and reactance. When including those six variables in a multilevel model, the results indicate that social support network, subjective distress, and the initial measure of clinical distress were significant predictors of the trajectories of OQ-30, whereas unemployment, sociocultural status and reactance were not significant. The results regarding social support network are in line with the literature, while results of socioeconomic status (unemployment and sociocultural level) move in an opposite direction in comparison to the available evidence. Moreover, the mental health findings (initial OQ-30 and subjective distress) confirm the contradictory body of literature produced in this domain. Finally, reactance seems to be a significant predictor in previous study in contradiction of our results. Overall, this endeavor constitutes important but preliminary evidence to enhance the production of bottom-up science within practice research networks in the global south.

19.
Adm Policy Ment Health ; 51(4): 439-454, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38530511

RESUMEN

Ecological momentary assessment (EMA) allows measuring intra-individual processes moment by moment, identifying and modeling, in a naturalistic way, individual levels and changes in different psychological processes. However, active EMA requires a high degree of adherence, as it implies a significant burden for patients. Moreover, there is still no consensus on standardized procedures for implementation. There have been few results in detecting desirable characteristics for the design and implementation of an EMA device. Studies that address these issues from the perspectives of participants in psychotherapeutic processes are needed. To analyze the perspectives of patients, therapists and supervisors on the implementation of an EMA device in a psychotherapeutic treatment for depression. The sample will include eight patients, eleven therapists and five supervisors, taken from a research project that implemented an EMA system for monitoring the dynamics of affectivity at the beginning of psychotherapies for depression. Semi-structured interviews specific to each group are being conducted and analyzed from a qualitative approach based on consensual qualitative research (CQR). Participants reported having a positive evaluation of the study's informational resources and implementation. Difficulties were expressed in responding in the morning hours and the importance of having a customized EMA that is tailored to the needs of the patients was expressed. Furthermore, patients and therapists agreed that the impact of the use of the monitoring system on treatment was neutral or positive. In contrast, patients considered the EMA to be positive for their daily life.


Asunto(s)
Evaluación Ecológica Momentánea , Psicoterapia , Investigación Cualitativa , Humanos , Psicoterapia/métodos , Adulto , Femenino , Masculino , Persona de Mediana Edad , Actitud del Personal de Salud , Depresión/terapia
20.
Brain Behav Immun ; 113: 44-55, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37406976

RESUMEN

BACKGROUND: Multiple sclerosis (MS) is an immune-mediated central nervous system disease whose course is unpredictable. Finding biomarkers that help to better comprehend the disease's pathogenesis is crucial for supporting clinical decision-making. Blood extracellular vesicles (EVs) are membrane-bound particles secreted by all cell types that contain information on the disease's pathological processes. PURPOSE: To identify the immune and nervous system-derived EV profile from blood that could have a specific role as biomarker in MS and assess its possible correlation with disease state. RESULTS: Higher levels of T cell-derived EVs and smaller size of neuron-derived EVs were associated with clinical relapse. The smaller size of the oligodendrocyte-derived EVs was related with motor and cognitive impairment. The proteomic analysis identified mannose-binding lectin serine protease 1 and complement factor H from immune system cell-derived EVs as autoimmune disease-associated proteins. We observed hepatocyte growth factor-like protein in EVs from T cells and inter-alpha-trypsin inhibitor heavy chain 2 from neurons as white matter injury-related proteins. In patients with MS, a specific protein profile was found in the EVs, higher levels of alpha-1-microglobulin and fibrinogen ß chain, lower levels of C1S and gelsolin in the immune system-released vesicles, and Talin-1 overexpression in oligodendrocyte EVs. These specific MS-associated proteins, as well as myelin basic protein in oligodendrocyte EVs, correlated with disease activity in the patients with MS. CONCLUSION: Neural-derived and immune-derived EVs found in blood appear to be good specific biomarkers in MS for reflecting the disease state.


Asunto(s)
Vesículas Extracelulares , Esclerosis Múltiple , Humanos , Esclerosis Múltiple/metabolismo , Proteómica , Encéfalo/patología , Vesículas Extracelulares/metabolismo , Sistema Inmunológico , Matriz Extracelular , Biomarcadores
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