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1.
Cell ; 184(3): 709-722.e13, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33482084

RESUMEN

Neural stem cells (NSCs) in the adult brain transit from the quiescent state to proliferation to produce new neurons. The mechanisms regulating this transition in freely behaving animals are, however, poorly understood. We customized in vivo imaging protocols to follow NSCs for several days up to months, observing their activation kinetics in freely behaving mice. Strikingly, NSC division is more frequent during daylight and is inhibited by darkness-induced melatonin signaling. The inhibition of melatonin receptors affected intracellular Ca2+ dynamics and promoted NSC activation. We further discovered a Ca2+ signature of quiescent versus activated NSCs and showed that several microenvironmental signals converge on intracellular Ca2+ pathways to regulate NSC quiescence and activation. In vivo NSC-specific optogenetic modulation of Ca2+ fluxes to mimic quiescent-state-like Ca2+ dynamics in freely behaving mice blocked NSC activation and maintained their quiescence, pointing to the regulatory mechanisms mediating NSC activation in freely behaving animals.


Asunto(s)
Células Madre Adultas/metabolismo , Calcio/metabolismo , Ritmo Circadiano , Espacio Intracelular/metabolismo , Células-Madre Neurales/metabolismo , Células Madre Adultas/citología , Células Madre Adultas/efectos de los fármacos , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Conducta Animal/efectos de los fármacos , División Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ritmo Circadiano/efectos de los fármacos , Citosol/metabolismo , Factor de Crecimiento Epidérmico/farmacología , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Melatonina/metabolismo , Ratones , Células-Madre Neurales/citología , Células-Madre Neurales/efectos de los fármacos , Optogenética , Transducción de Señal/efectos de los fármacos , Triptaminas/farmacología
2.
Cell ; 184(2): 489-506.e26, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33338423

RESUMEN

Single-cell transcriptomics has been widely applied to classify neurons in the mammalian brain, while systems neuroscience has historically analyzed the encoding properties of cortical neurons without considering cell types. Here we examine how specific transcriptomic types of mouse prefrontal cortex (PFC) projection neurons relate to axonal projections and encoding properties across multiple cognitive tasks. We found that most types projected to multiple targets, and most targets received projections from multiple types, except PFC→PAG (periaqueductal gray). By comparing Ca2+ activity of the molecularly homogeneous PFC→PAG type against two heterogeneous classes in several two-alternative choice tasks in freely moving mice, we found that all task-related signals assayed were qualitatively present in all examined classes. However, PAG-projecting neurons most potently encoded choice in cued tasks, whereas contralateral PFC-projecting neurons most potently encoded reward context in an uncued task. Thus, task signals are organized redundantly, but with clear quantitative biases across cells of specific molecular-anatomical characteristics.


Asunto(s)
Cognición/fisiología , Neuronas/fisiología , Corteza Prefrontal/fisiología , Análisis y Desempeño de Tareas , Animales , Calcio/metabolismo , Conducta de Elección , Señales (Psicología) , Imagenología Tridimensional , Integrasas/metabolismo , Ratones Endogámicos C57BL , Odorantes , Optogenética , Sustancia Gris Periacueductal/fisiología , Recompensa , Análisis de la Célula Individual , Transcriptoma/genética
3.
Mol Cell ; 80(2): 227-236.e5, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-32991829

RESUMEN

The pathways for ribosomal RNA (rRNA) maturation diverge greatly among the domains of life. In the Gram-positive model bacterium, Bacillus subtilis, the final maturation steps of the two large ribosomal subunit (50S) rRNAs, 23S and 5S pre-rRNAs, are catalyzed by the double-strand specific ribonucleases (RNases) Mini-RNase III and RNase M5, respectively. Here we present a protocol that allowed us to solve the 3.0 and 3.1 Å resolution cryoelectron microscopy structures of these RNases poised to cleave their pre-rRNA substrates within the B. subtilis 50S particle. These data provide the first structural insights into rRNA maturation in bacteria by revealing how these RNases recognize and process double-stranded pre-rRNA. Our structures further uncover how specific ribosomal proteins act as chaperones to correctly fold the pre-rRNA substrates and, for Mini-III, anchor the RNase to the ribosome. These r-proteins thereby serve a quality-control function in the process from accurate ribosome assembly to rRNA processing.


Asunto(s)
Bacillus subtilis/enzimología , Proteínas Bacterianas/química , Precursores del ARN/metabolismo , Ribonucleasas/química , Subunidades Ribosómicas Grandes Bacterianas/metabolismo , Bacillus subtilis/ultraestructura , Proteínas Bacterianas/ultraestructura , Secuencia de Bases , Microscopía por Crioelectrón , Modelos Moleculares , Precursores del ARN/ultraestructura , Ribonucleasas/ultraestructura , Subunidades Ribosómicas Grandes Bacterianas/ultraestructura , Especificidad por Sustrato
4.
Mol Cell ; 80(1): 156-163.e6, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-33007255

RESUMEN

The production of alternative RNA variants contributes to the tissue-specific regulation of gene expression. In the animal nervous system, a systematic shift toward distal sites of transcription termination produces transcript signatures that are crucial for neuron development and function. Here, we report that, in Drosophila, the highly conserved protein ELAV globally regulates all sites of neuronal 3' end processing and directly binds to proximal polyadenylation sites of target mRNAs in vivo. We uncover an endogenous strategy of functional gene rescue that safeguards neuronal RNA signatures in an ELAV loss-of-function context. When not directly repressed by ELAV, the transcript encoding the ELAV paralog FNE acquires a mini-exon, generating a new protein able to translocate to the nucleus and rescue ELAV-mediated alternative polyadenylation and alternative splicing. We propose that exon-activated functional rescue is a more widespread mechanism that ensures robustness of processes regulated by a hierarchy, rather than redundancy, of effectors.


Asunto(s)
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas ELAV/metabolismo , Exones/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Proteínas de Unión al ARN/metabolismo , Animales , Masculino , Unión Proteica , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transcriptoma/genética
5.
J Biol Chem ; 300(4): 107203, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38508311

RESUMEN

We are entering an exciting time in structural biology where artificial intelligence can be used to predict protein structures with greater accuracy than ever before. Extending this level of accuracy to the predictions of disulfide-rich peptide structures is likely to be more challenging, at least in the short term, given the tight packing of cysteine residues and the numerous ways that the disulfide bonds can potentially be linked. It has been previously shown in many cases that several disulfide bond connectivities can be accommodated by a single set of NMR-derived structural data without significant violations. Disulfide-rich peptides are prevalent throughout nature, and arguably the most well-known are those present in venoms from organisms such as cone snails. Here, we have determined the first three-dimensional structure and disulfide connectivity of a U-superfamily cone snail venom peptide, TxVIIB. TxVIIB has a VI/VII cysteine framework that is generally associated with an inhibitor cystine knot (ICK) fold; however, AlphaFold predicted that the peptide adopts a mini-granulin fold with a granulin disulfide connectivity. Our experimental studies using NMR spectroscopy and orthogonal protection of cysteine residues indicate that TxVIIB indeed adopts a mini-granulin fold but with the ICK disulfide connectivity. Our findings provide structural insight into the underlying features that govern formation of the mini-granulin fold rather than the ICK fold and will provide fundamental information for prediction algorithms, as the subtle complexity of disulfide isomers may be not adequately addressed by the current prediction algorithms.


Asunto(s)
Conotoxinas , Animales , Secuencia de Aminoácidos , Conotoxinas/química , Caracol Conus , Cisteína/química , Disulfuros/química , Granulinas/química , Granulinas/metabolismo , Modelos Moleculares , Resonancia Magnética Nuclear Biomolecular , Pliegue de Proteína
6.
Mol Biol Evol ; 41(8)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39107250

RESUMEN

Crop disease pandemics are often driven by asexually reproducing clonal lineages of plant pathogens that reproduce asexually. How these clonal pathogens continuously adapt to their hosts despite harboring limited genetic variation, and in absence of sexual recombination remains elusive. Here, we reveal multiple instances of horizontal chromosome transfer within pandemic clonal lineages of the blast fungus Magnaporthe (Syn. Pyricularia) oryzae. We identified a horizontally transferred 1.2Mb accessory mini-chromosome which is remarkably conserved between M. oryzae isolates from both the rice blast fungus lineage and the lineage infecting Indian goosegrass (Eleusine indica), a wild grass that often grows in the proximity of cultivated cereal crops. Furthermore, we show that this mini-chromosome was horizontally acquired by clonal rice blast isolates through at least nine distinct transfer events over the past three centuries. These findings establish horizontal mini-chromosome transfer as a mechanism facilitating genetic exchange among different host-associated blast fungus lineages. We propose that blast fungus populations infecting wild grasses act as genetic reservoirs that drive genome evolution of pandemic clonal lineages that afflict cereal crops.


Asunto(s)
Evolución Molecular , Transferencia de Gen Horizontal , Cromosomas Fúngicos/genética , Ascomicetos/genética , Enfermedades de las Plantas/microbiología , Genoma Fúngico
7.
Brief Bioinform ; 25(1)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38171928

RESUMEN

Recent advances in spatial transcriptomics (ST) have enabled comprehensive profiling of gene expression with spatial information in the context of the tissue microenvironment. However, with the improvements in the resolution and scale of ST data, deciphering spatial domains precisely while ensuring efficiency and scalability is still challenging. Here, we develop SGCAST, an efficient auto-encoder framework to identify spatial domains. SGCAST adopts a symmetric graph convolutional auto-encoder to learn aggregated latent embeddings via integrating the gene expression similarity and the proximity of the spatial spots. This framework in SGCAST enables a mini-batch training strategy, which makes SGCAST memory-efficient and scalable to high-resolution spatial transcriptomic data with a large number of spots. SGCAST improves the overall accuracy of spatial domain identification on benchmarking data. We also validated the performance of SGCAST on ST datasets at various scales across multiple platforms. Our study illustrates the superior capacity of SGCAST on analyzing spatial transcriptomic data.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Benchmarking , Aprendizaje
8.
J Biol Chem ; 299(11): 105330, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37820866

RESUMEN

Cell cycle errors can lead to mutations, chromosomal instability, or death; thus, the precise control of cell cycle progression is essential for viability. The nutrient-sensing posttranslational modification, O-GlcNAc, regulates the cell cycle allowing one central control point directing progression of the cell cycle. O-GlcNAc is a single N-acetylglucosamine sugar modification to intracellular proteins that is dynamically added and removed by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), respectively. These enzymes act as a rheostat to fine-tune protein function in response to a plethora of stimuli from nutrients to hormones. O-GlcNAc modulates mitogenic growth signaling, senses nutrient flux through the hexosamine biosynthetic pathway, and coordinates with other nutrient-sensing enzymes to progress cells through Gap phase 1 (G1). At the G1/S transition, O-GlcNAc modulates checkpoint control, while in S Phase, O-GlcNAcylation coordinates the replication fork. DNA replication errors activate O-GlcNAcylation to control the function of the tumor-suppressor p53 at Gap Phase 2 (G2). Finally, in mitosis (M phase), O-GlcNAc controls M phase progression and the organization of the mitotic spindle and midbody. Critical for M phase control is the interplay between OGT and OGA with mitotic kinases. Importantly, disruptions in OGT and OGA activity induce M phase defects and aneuploidy. These data point to an essential role for the O-GlcNAc rheostat in regulating cell division. In this review, we highlight O-GlcNAc nutrient sensing regulating G1, O-GlcNAc control of DNA replication and repair, and finally, O-GlcNAc organization of mitotic progression and spindle dynamics.


Asunto(s)
Mitosis , Procesamiento Proteico-Postraduccional , Acetilglucosamina/metabolismo , Acetilglucosaminidasa/metabolismo , Mutación , N-Acetilglucosaminiltransferasas/genética , N-Acetilglucosaminiltransferasas/metabolismo , Transducción de Señal , Humanos , Animales
9.
Am J Physiol Lung Cell Mol Physiol ; 326(6): L736-L753, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38651940

RESUMEN

Systemic sclerosis (SSc) with interstitial lung disease (SSc-ILD) lacks curative pharmacological treatments, thus necessitating effective animal models for candidate drug discovery. Existing bleomycin (BLM)-induced SSc-ILD mouse models feature spatially limited pulmonary fibrosis, spontaneously resolving after 28 days. Here, we present an alternative BLM administration approach in female C57BL/6 mice, combining oropharyngeal aspiration (OA) and subcutaneous mini-pump delivery (pump) of BLM to induce a sustained and more persistent fibrosis, while retaining stable skin fibrosis. A dose-finding study was performed with BLM administered as 10 µg (OA) +80 mg/kg (pump) (10 + 80), 10 + 100, and 15 + 100. Forty-two days after OA, micro-computed tomography (micro-CT) imaging and histomorphometric analyses showed that the 10 + 100 and 15 + 100 treatments induced significant alterations in lung micro-CT-derived readouts, Ashcroft score, and more severe fibrosis grades compared with saline controls. In addition, a marked reduction in hypodermal thickness was observed in the 15 + 100 group. A time-course characterization of the BLM 15 + 100 treatment at days 28, 35, and 42, including longitudinal micro-CT imaging, revealed progressing alterations in lung parameters. Lung histology highlighted a sustained fibrosis accompanied by a reduction in hypodermis thickness throughout the explored time-window, with a time-dependent increase in fibrotic biomarkers detected by immunofluorescence analysis. BLM-induced alterations were partly mitigated by Nintedanib treatment. Our optimized BLM delivery approach leads to extensive and persistent lung fibrotic lesions coupled with cutaneous fibrotic alterations: it thus represents a significant advance compared with current preclinical models of BLM-induced SSc-ILD.NEW & NOTEWORTHY This study introduces an innovative approach to enhance the overall performance of the mouse bleomycin (BLM)-induced model for systemic sclerosis with interstitial lung disease (SSc-ILD). By combining oropharyngeal aspiration and subcutaneous mini-pump delivery of BLM, our improved model leads to sustained lung fibrosis and stable skin fibrosis in female C57BL/6 mice. The optimized 15 + 100 treatment results in extensive and persistent lung fibrotic lesions and thus represents a significant improvement over existing preclinical models of BLM-induced SSc-ILD.


Asunto(s)
Bleomicina , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Fibrosis Pulmonar , Animales , Bleomicina/administración & dosificación , Bleomicina/toxicidad , Femenino , Fibrosis Pulmonar/patología , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/tratamiento farmacológico , Ratones , Esclerodermia Sistémica/patología , Esclerodermia Sistémica/tratamiento farmacológico , Esclerodermia Sistémica/complicaciones , Microtomografía por Rayos X , Piel/patología , Piel/efectos de los fármacos , Pulmón/patología , Pulmón/efectos de los fármacos , Pulmón/diagnóstico por imagen , Orofaringe/patología , Orofaringe/efectos de los fármacos , Orofaringe/diagnóstico por imagen , Enfermedades Pulmonares Intersticiales/patología , Enfermedades Pulmonares Intersticiales/tratamiento farmacológico , Enfermedades Pulmonares Intersticiales/inducido químicamente , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen
10.
Curr Issues Mol Biol ; 46(7): 6940-6950, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-39057055

RESUMEN

Carotenoids, having strong antioxidant properties, have been associated with neurodegenerative conditions like dementia and glaucoma, characterized by neuronal loss leading to cognitive and visual dysfunction. Therefore, carotenoids have attracted attention as factors predictive of the onset and progression of these neurodegenerative diseases. However, the impact of carotenoids on cognitive impairment and glaucomatous visual field defects remains unexplored. We conducted a retrospective, observational clinical study to investigate the association between skin carotenoid (SC) levels and cognitive impairment, as screened by the Mini-Cog test, in glaucoma patients. The study included 406 participants and 812 eyes were examined (average age: 69.7 ± 11.4 years; 228 men, 178 women) with various types of glaucoma: primary open angle (57.6%), exfoliation (18.6%), and other types (23.8%). SC levels were estimated via pressure-mediated reflection spectroscopy. Mixed-effects regression models were utilized to examine the relationship between SC levels, visual field defects, and Mini-Cog results. Of the participants, 28 (6.9%) tested positive on the Mini-Cog, suggesting cognitive impairment. The average SC level in the Mini-Cog positive group was significantly lower than in the negative group (269.5 ± 86.4 A.U. vs. 329.2 ± 120.4 A.U., respectively; p = 0.01). Additionally, the visual field mean deviation (MD) in the Mini-Cog positive group was notably worse than that in the negative group (-19.64 ± 9.07 dB vs. -12.46 ± 9.28 dB, respectively; p < 0.0001). The mixed-effects regression analysis revealed a significant association between Mini-Cog positivity and lower SC levels (p = 0.0006), although SC levels did not significantly correlate with MD (p = 0.3). Our findings suggest that cognitive impairment in glaucoma patients is associated with lower SC levels, underscoring the potential benefits of maintaining carotenoid levels to slow cognitive function decline. The protective role of carotenoids in glaucoma merits further investigation.

11.
Gastroenterology ; 164(5): 841-846, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36702361

RESUMEN

Using colorectal cancer as a model, we review some of the insights into cancer evolution afforded by cancer sequencing. These include nonlinear and neutral evolution; polyclonality of driver mutations and parallel evolution in adenomas, although these are rare in carcinomas; the ability of mutational processes to shape evolution against the force of selection; the presence of rare driver genes that function in the same signaling pathways as the longstanding canonical drivers; and the existence of selective windows that constrain the functional effects of cancer driver mutations within limits. Many of these nascent evolutionary paradigms are potentially important for treating colorectal cancers as well as understanding their development.


Asunto(s)
Carcinoma , Neoplasias Colorrectales , Humanos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Carcinogénesis/genética , Transformación Celular Neoplásica/genética , Mutación , Carcinoma/patología
12.
Development ; 148(18)2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34383894

RESUMEN

Neural stem cells (NSCs) are maintained in specific regions of the postnatal brain and contribute to its structural and functional plasticity. However, the long-term renewal potential of NSCs and their mode of division remain elusive. The use of advanced in vivo live imaging approaches may expand our knowledge of NSC physiology and provide new information for cell replacement therapies. In this Review, we discuss the in vivo imaging methods used to study NSC dynamics and recent live-imaging results with respect to specific intracellular pathways that allow NSCs to integrate and decode different micro-environmental signals. Lastly, we discuss future directions that may provide answers to unresolved questions regarding NSC physiology.


Asunto(s)
Células-Madre Neurales/fisiología , Animales , Encéfalo/fisiología , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Humanos , Atención Posnatal/métodos , Transducción de Señal/fisiología
13.
BMC Med ; 22(1): 176, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664766

RESUMEN

BACKGROUND: There is an urgent unmet need for effective initial treatment for acute graft-versus-host disease (aGVHD) adding to the standard first-line therapy with corticosteroids after allogeneic haematopoietic stem cell transplantation (allo-HSCT). METHODS: We performed a multicentre, open-label, randomized, phase 3 study. Eligible patients (aged 15 years or older, had received allo-HSCT for a haematological malignancy, developed aGVHD, and received no previous therapies for aGVHD) were randomly assigned (1:1) to receive either 5 mg/m2 MTX on Days 1, 3, or 8 and then combined with corticosteroids or corticosteroids alone weekly. RESULTS: The primary endpoint was the overall response rate (ORR) on Day 10. A total of 157 patients were randomly assigned to receive either MTX plus corticosteroids (n = 78; MTX group) or corticosteroids alone (n = 79; control group). The Day 10 ORR was 97% for the MTX group and 81% for the control group (p = .005). Among patients with mild aGVHD, the Day 10 ORR was 100% for the MTX group and 86% for the control group (p = .001). The 1-year estimated failure-free survival was 69% for the MTX group and 41% for the control group (p = .002). There were no differences in treatment-related adverse events between the two groups. CONCLUSIONS: In conclusion, mini-dose MTX combined with corticosteroids can significantly improve the ORR in patients with aGVHD and is well tolerated, although it did not achieve the prespecified 20% improvement with the addition of MTX. TRIAL REGISTRATION: The trial was registered with clinicaltrials.gov (NCT04960644).


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Metotrexato , Metilprednisolona , Humanos , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Femenino , Masculino , Metotrexato/administración & dosificación , Metotrexato/uso terapéutico , Persona de Mediana Edad , Adulto , Metilprednisolona/uso terapéutico , Metilprednisolona/administración & dosificación , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Adulto Joven , Resultado del Tratamiento , Quimioterapia Combinada , Anciano , Adolescente , Enfermedad Aguda
14.
Small ; 20(9): e2307186, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37857583

RESUMEN

Flexible perovskite solar cells (F-PSCs) have emerged as promising alternatives to conventional silicon solar cells for applications in portable and wearable electronics. However, the mechanical stability of inherently brittle perovskite, due to residual lattice stress and ductile fracture formation, poses significant challenges to the long-term photovoltaic performance and device lifetime. In this paper, to address this issue, a dynamic "ligament" composed of supramolecular poly(dimethylsiloxane) polyurethane (DSSP-PPU) is introduced into the grain boundaries of the PSCs, facilitating the release of residual stress and softening of the grain boundaries. Remarkably, this dynamic "ligament" exhibits excellent self-healing properties and enables the healing of cracks in perovskite films at room temperature. The obtained PSCs have achieved power conversion efficiencies of 23.73% and 22.24% for rigid substrates and flexible substrates, respectively, also 17.32% for flexible mini-modules. Notably, the F-PSCs retain nearly 80% of their initial efficiency even after subjecting the F-PSCs to 8000 bending cycles (r = 2 mm), which can further recover to almost 90% of the initial efficiency through the self-healing process. This remarkable improvement in device stability and longevity holds great promise for extending the overall lifetime of F-PSCs.

15.
Mod Pathol ; 37(7): 100509, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38704030

RESUMEN

Acute promyelocytic leukemia (APL) with variant RARA translocation is linked to over 15 partner genes. Recent publications encompassing 6 cases have expanded the spectrum of RARA partners to torque teno mini virus (TTMV). This entity is likely underrecognized due to the lack of clinician and pathologist familiarity, inability to detect the fusion using routine testing modalities, and informatic challenges in its recognition within next-generation sequencing (NGS) data. We describe a clinicopathologic approach and provide the necessary tools to screen and diagnose APL with TTMV::RARA using existing clinical DNA- or RNA-based NGS assays, which led to the identification of 4 cases, all without other known cytogenetic/molecular drivers. One was identified prospectively and 3 retrospectively, including 2 from custom automated screening of multiple data sets (50,257 cases of hematopoietic malignancy, including 4809 acute myeloid leukemia/myeloid sarcoma/APL cases). Two cases presented as myeloid sarcoma, including 1 with multiple relapses after acute myeloid leukemia-type chemotherapy and hematopoietic stem cell transplant. Two cases presented as leukemia, had a poor response to induction chemotherapy, but achieved remission upon reinduction (including all-trans retinoic acid in 1 case) and subsequent hematopoietic stem cell transplant. Neoplastic cells demonstrated features of APL including frequent azurophilic granules and dim/absent CD34 and HLA-DR expression. RARA rearrangement was not detected by karyotype or fluorescent in situ hybridization. Custom analysis of NGS fusion panel data identified TTMV::RARA rearrangements and, in the prospectively identified case, facilitated monitoring in sequential bone marrow samples. APL with TTMV::RARA is a rare leukemia with a high rate of treatment failure in described cases. The diagnosis should be considered in leukemias with features of APL that lack detectable RARA fusions and other drivers, and may be confirmed by appropriate NGS tests with custom informatics. Incorporation of all-trans retinoic acid may have a role in treatment but requires accurate recognition of the fusion for appropriate classification as APL.


Asunto(s)
Leucemia Promielocítica Aguda , Proteínas de Fusión Oncogénica , Receptor alfa de Ácido Retinoico , Torque teno virus , Humanos , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/diagnóstico , Receptor alfa de Ácido Retinoico/genética , Masculino , Torque teno virus/genética , Proteínas de Fusión Oncogénica/genética , Femenino , Adulto , Persona de Mediana Edad , Secuenciación de Nucleótidos de Alto Rendimiento
16.
J Transl Med ; 22(1): 59, 2024 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-38229174

RESUMEN

BACKGROUND: Loss-of-function mutations in the PRKN gene, encoding Parkin, are the most common cause of autosomal recessive Parkinson's disease (PD). We have previously identified mitoch ondrial Stomatin-like protein 2 (SLP-2), which functions in the assembly of respiratory chain proteins, as a Parkin-binding protein. Selective knockdown of either Parkin or SLP-2 led to reduced mitochondrial and neuronal function in neuronal cells and Drosophila, where a double knockdown led to a further worsening of Parkin-deficiency phenotypes. Here, we investigated the minimal Parkin region involved in the Parkin-SLP-2 interaction and explored the ability of Parkin-fragments and peptides from this minimal region to restore mitochondrial function. METHODS: In fibroblasts, human induced pluripotent stem cell (hiPSC)-derived neurons, and neuroblastoma cells the interaction between Parkin and SLP-2 was investigated, and the Parkin domain responsible for the binding to SLP-2 was mapped. High resolution respirometry, immunofluorescence analysis and live imaging were used to analyze mitochondrial function. RESULTS: Using a proximity ligation assay, we quantitatively assessed the Parkin-SLP-2 interaction in skin fibroblasts and hiPSC-derived neurons. When PD-associated PRKN mutations were present, we detected a significantly reduced interaction between the two proteins. We found a preferential binding of SLP-2 to the N-terminal part of Parkin, with a highest affinity for the RING0 domain. Computational modeling based on the crystal structure of Parkin protein predicted several potential binding sites for SLP-2 within the Parkin RING0 domain. Amongst these, three binding sites were observed to overlap with natural PD-causing missense mutations, which we demonstrated interfere substantially with the binding of Parkin to SLP-2. Finally, delivery of the isolated Parkin RING0 domain and a Parkin mini-peptide, conjugated to cell-permeant and mitochondrial transporters, rescued compromised mitochondrial function in Parkin-deficient neuroblastoma cells and hiPSC-derived neurons with endogenous, disease causing PRKN mutations. CONCLUSIONS: These findings place further emphasis on the importance of the protein-protein interaction between Parkin and SLP-2 for the maintenance of optimal mitochondrial function. The possibility of restoring an abolished binding to SLP-2 by delivering the Parkin RING0 domain or the Parkin mini-peptide involved in this specific protein-protein interaction into cells might represent a novel organelle-specific therapeutic approach for correcting mitochondrial dysfunction in Parkin-linked PD.


Asunto(s)
Células Madre Pluripotentes Inducidas , Enfermedades Mitocondriales , Neuroblastoma , Enfermedad de Parkinson , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Enfermedad de Parkinson/genética , Péptidos
17.
J Urol ; 212(3): 483-493, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39115125

RESUMEN

PURPOSE: We sought to evaluate the technical feasibility of performing a combined robotically assisted mini-percutaneous nephrolithotomy (PCNL) and flexible ureteroscopy (URS) procedure by a single urologist using the MONARCH Platform, Urology (Johnson & Johnson MedTech, Redwood City, California). MATERIAL AND METHODS: In this prospective, first-in-human clinical trial, 13 patients underwent robotically-assisted PCNL for renal calculi at the University of California-Irvine, Department of Urology. Successful completion of the procedure was assessed as the primary endpoint. Postoperative adverse events were monitored for 30 days following the completion of the procedure. Stone ablation efficiency was evaluated on postoperative day 30 with low-dose 2-3 mm slice CT scans. Patients were classified according to the maximum length of their residual stone fragments as either absolute stone-free (Grade A), < 2 mm remnants (Grade B), or 2.1-4.0 mm remnants (Grade C). RESULTS: The combined robotic mini-PCNL and URS procedure was successfully completed in 12 of 13 procedures. No robotic device-related adverse events occurred. Preoperative stone burden was quantified by both maximum linear measurement (median 32.8 mm) as well as by CT-based volume (median 1645.9 mm3). Using the unique robotically assisted targeting system, percutaneous access was gained directly through the center of the renal papilla in a single pass in all cases. Median operative time was 187 minutes (range: 83-383 minutes). On postoperative day 30, a 98.7% (range: 72.9%-100.0%) volume reduction was achieved, with 5 Grade A (38.5%), 1 Grade B (7.7%), and 2 Grade C (15.4%). Three patients experienced complications (2 grade 1 and one grade 2 Clavien-Dindo). CONCLUSIONS: Our preliminary investigation demonstrates the safety, efficacy, and feasibility of a unique robotic-assisted combined mini-PCNL and URS platform.


Asunto(s)
Estudios de Factibilidad , Cálculos Renales , Nefrolitotomía Percutánea , Procedimientos Quirúrgicos Robotizados , Ureteroscopía , Humanos , Ureteroscopía/métodos , Ureteroscopía/instrumentación , Estudios Prospectivos , Nefrolitotomía Percutánea/métodos , Nefrolitotomía Percutánea/instrumentación , Masculino , Cálculos Renales/cirugía , Persona de Mediana Edad , Femenino , Procedimientos Quirúrgicos Robotizados/métodos , Adulto , Litotricia/métodos , Litotricia/instrumentación , Anciano , Ureteroscopios , Diseño de Equipo , Resultado del Tratamiento
18.
New Phytol ; 241(3): 1266-1276, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37984076

RESUMEN

The fungal pathogen, Magnaporthe oryzae Triticum pathotype, causing wheat blast disease was first identified in South America and recently spread across continents to South Asia and Africa. Here, we studied the genetic relationship among isolates found on the three continents. Magnaporthe oryzae strains closely related to a South American field isolate B71 were found to have caused the wheat blast outbreaks in South Asia and Africa. Genomic variation among isolates from the three continents was examined using an improved B71 reference genome and whole-genome sequences. We found strong evidence to support that the outbreaks in Bangladesh and Zambia were caused by the introductions of genetically separated isolates, although they were all close to B71 and, therefore, collectively referred to as the B71 branch. In addition, B71 branch strains carried at least one supernumerary mini-chromosome. Genome assembly of a Zambian strain revealed that its mini-chromosome was similar to the B71 mini-chromosome but with a high level of structural variation. Our findings show that while core genomes of the multiple introductions are highly similar, the mini-chromosomes have undergone marked diversification. The maintenance of the mini-chromosome and rapid genomic changes suggest the mini-chromosomes may serve important virulence or niche adaptation roles under diverse environmental conditions.


Asunto(s)
Ascomicetos , Magnaporthe , Triticum , Triticum/genética , Bangladesh/epidemiología , Zambia/epidemiología , Magnaporthe/genética , Cromosomas , Enfermedades de las Plantas/microbiología
19.
Hum Reprod ; 39(4): 733-741, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38327007

RESUMEN

STUDY QUESTION: What are the complications of transvaginal ethanol sclerotherapy for the treatment of endometriomas? SUMMARY ANSWER: Sclerotherapy is a reliable, minimally invasive method applicable in outpatient procedures but with specific and potential life-threatening complications that need to be identified and prevented. WHAT IS KNOWN ALREADY: There are currently few data on the use of transvaginal ethanol sclerotherapy, and we mainly note septic complications. STUDY DESIGN, SIZE, DURATION: A retrospective observational cohort study was carried out. The study was conducted at an academic hospital and included 126 women aged 31.9 ± 5.5 years (mean ± SD), between November 2013 and June 2021. We analyzed a total of 157 ethanol sclerotherapy treatment (EST), treated by 131 EST procedures, in 126 women. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study included women with an indication for transvaginal ethanol sclerotherapy. Indications were women with at least one endometrioma over 10 mm, isolated or associated with other endometriosis locations, requiring treatment for pain or infertility before assisted reproductive treatment. We followed a standardized transvaginal ethanol sclerotherapy procedure consisting of an ultrasound-guided transvaginal puncture of one or more endometriomas under general anesthesia. The cyst content was completely removed and flushed with saline solution. Ethanol (96%) was injected at 60% of the initial volume of the endometrioma, remained in the cyst for 10 min and was then completely removed. Ethanol loss was defined as a loss of 5 ml or more than 10% of the initial volume of the injected ethanol. Failure was defined by the contraindication of endometrioma puncture because of interposition of the digestive tract, ethanol loss in the previous endometrioma treated (in case of multiple ESTs), failure to aspirate the endometriotic fluid, contraindication to start ethanol injection owing to saline solution leakage, or contraindication to continue ethanol injection owing to suspicions of ethanol leakage at sonography. Intraoperative complications were defined by ethanol loss, positive blood alcohol level, and ethanol intoxication. Postoperative complications were defined by fever, biological inflammatory syndrome, and ovarian abscess. Complications were classified according to the Clavien and Dindo surgical classification, which is a system for classifying postoperative complications in five grades of increasing severity. MAIN RESULTS AND THE ROLE OF CHANCE: We reported a total of 17/157 (10.8%) transvaginal ethanol sclerotherapy failures during 14/131 (10.7%) transvaginal ethanol sclerotherapy procedures in 13/126 (10.3%) women. In the same sets of data, complication was reported for 15/157 (9.5%) transvaginal ethanol sclerotherapy in 13/131 (9.9%) transvaginal ethanol sclerotherapy procedures in 13/126 (10.3%) women. Nine of 126 women (7.1%) had a grade I complication, one (0.8%) had a grade II complication (medical treatment for suspicion of pelvic infection), two (1.6%) had a grade III complication (ovarian abscess) and one (0.8%) had a grade IV complication (ethanol intoxication). We did not observe any grade V complications. LIMITATIONS, REASONS FOR CAUTION: This was a retrospective study and pain assessment not considered. The benefit-risk balance of endometrioma transvaginal ethanol sclerotherapy was not evaluated. WIDER IMPLICATIONS OF THE FINDINGS: Our study is the first to evaluate the complications of transvaginal ethanol sclerotherapy with such a large cohort of women in a standardized protocol. Transvaginal ethanol sclerotherapy seems to be an effective alternative to laparoscopic surgery in the management of endometriomas and limits the alteration of ovarian reserve. Transvaginal ethanol sclerotherapy is a reliable, minimally invasive method applicable on an outpatient basis. The majority of complications are Clavien-Dindo ≤IV, for which preventative measures, or at least early diagnosis and treatment, can be easily performed. The risk of ethanol intoxication is rare, but it is a life-threatening risk that must be avoided by appropriate implementation and promotion of the sclerotherapy procedures. STUDY FUNDING/COMPETING INTEREST(S): None. TRIAL REGISTRATION NUMBER: Aix Marseille University's ethics committee registration number 2021-06-03-01.


Asunto(s)
Intoxicación Alcohólica , Quistes , Endometriosis , Enfermedades del Ovario , Femenino , Humanos , Masculino , Endometriosis/complicaciones , Estudios Retrospectivos , Escleroterapia/efectos adversos , Escleroterapia/métodos , Etanol/efectos adversos , Absceso/complicaciones , Intoxicación Alcohólica/complicaciones , Solución Salina , Enfermedades del Ovario/diagnóstico por imagen , Enfermedades del Ovario/terapia , Enfermedades del Ovario/complicaciones , Complicaciones Posoperatorias
20.
J Nutr ; 154(1): 252-260, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38035998

RESUMEN

BACKGROUND: It remains unclear if adherence to the planetary healthy diet (PHD), designed to improve human and environmental health, is associated with better cognitive function in aging, and if this association differs by apolipoprotein E (APOE) genotype. OBJECTIVES: We aimed to examine the association between the PHD pattern and risk of poor cognitive function, and to further assess whether the APOE ε4 allele could modify this association. METHODS: The study included 16,736 participants from the Singapore Chinese Health Study. The PHD score was calculated using data from a validated 165-item food frequency questionnaire at baseline (1993-1998), with higher scores indicating greater adherence to the PHD. Cognitive function was assessed by the Singapore-modified Mini-Mental State Examination at follow-up 3 visits (2014-2016). A subset of 9313 participants had APOE genotype data. Logistic regression models were used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs), with adjustment for potential confounders. RESULTS: We identified 2397 (14.3%) cases of poor cognitive function. In the total population, OR (95% CI) of poor cognitive function for each one-SD increment in the PHD score was 0.89 (0.85, 0.93). Carriers of APOE ε4 allele had increased risk of poor cognitive function (OR: 1.36, 95% CI: 1.15, 1.61). There was a significant interaction between the PHD score and the APOE ε4 allele (P-interaction = 0.042). Each one-SD increment in the PHD score was significantly associated with lower risk of poor cognitive function (OR: 0.89; 95% CI: 0.83, 0.96) in non-carriers of APOE ε4 allele, but not in APOE ε4 allele carriers (OR: 1.04, 95% CI: 0.89, 1.23). CONCLUSIONS: Midlife adherence to the PHD was associated with reduced risk of poor cognitive function in later life. However, this was not observed in carriers of APOE ε4 allele who had higher risk of poor cognitive function.


Asunto(s)
Apolipoproteína E4 , Dieta Saludable , Adulto , Humanos , Apolipoproteína E4/genética , Singapur , Pruebas Neuropsicológicas , Apolipoproteínas E/genética , Cognición , Genotipo , Alelos
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