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1.
Cell ; 182(6): 1474-1489.e23, 2020 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-32841603

RESUMEN

Widespread changes to DNA methylation and chromatin are well documented in cancer, but the fate of higher-order chromosomal structure remains obscure. Here we integrated topological maps for colon tumors and normal colons with epigenetic, transcriptional, and imaging data to characterize alterations to chromatin loops, topologically associated domains, and large-scale compartments. We found that spatial partitioning of the open and closed genome compartments is profoundly compromised in tumors. This reorganization is accompanied by compartment-specific hypomethylation and chromatin changes. Additionally, we identify a compartment at the interface between the canonical A and B compartments that is reorganized in tumors. Remarkably, similar shifts were evident in non-malignant cells that have accumulated excess divisions. Our analyses suggest that these topological changes repress stemness and invasion programs while inducing anti-tumor immunity genes and may therefore restrain malignant progression. Our findings call into question the conventional view that tumor-associated epigenomic alterations are primarily oncogenic.


Asunto(s)
Cromatina/metabolismo , Cromosomas/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Metilación de ADN , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica/genética , División Celular , Senescencia Celular/genética , Secuenciación de Inmunoprecipitación de Cromatina , Cromosomas/genética , Estudios de Cohortes , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Biología Computacional , Metilación de ADN/genética , Epigenómica , Células HCT116 , Humanos , Hibridación Fluorescente in Situ , Microscopía Electrónica de Transmisión , Simulación de Dinámica Molecular , RNA-Seq , Análisis Espacial , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo
3.
Nat Immunol ; 21(8): 868-879, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32690950

RESUMEN

STING is essential for control of infections and for tumor immunosurveillance, but it can also drive pathological inflammation. STING resides on the endoplasmic reticulum (ER) and traffics following stimulation to the ERGIC/Golgi, where signaling occurs. Although STING ER exit is the rate-limiting step in STING signaling, the mechanism that drives this process is not understood. Here we identify STEEP as a positive regulator of STING signaling. STEEP was associated with STING and promoted trafficking from the ER. This was mediated through stimulation of phosphatidylinositol-3-phosphate (PtdIns(3)P) production and ER membrane curvature formation, thus inducing COPII-mediated ER-to-Golgi trafficking of STING. Depletion of STEEP impaired STING-driven gene expression in response to virus infection in brain tissue and in cells from patients with STING-associated diseases. Interestingly, STING gain-of-function mutants from patients interacted strongly with STEEP, leading to increased ER PtdIns(3)P levels and membrane curvature. Thus, STEEP enables STING signaling by promoting ER exit.


Asunto(s)
Retículo Endoplásmico/metabolismo , Regulación de la Expresión Génica/fisiología , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Transducción de Señal/fisiología , Animales , Retículo Endoplásmico/inmunología , Humanos , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/metabolismo , Proteínas de la Membrana/inmunología , Ratones , Proteínas del Tejido Nervioso/inmunología , Proteínas Nucleares , Transporte de Proteínas/fisiología
4.
Nat Immunol ; 17(2): 150-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26595890

RESUMEN

Mucosal surfaces are exposed to environmental substances and represent a major portal of entry for microorganisms. The innate immune system is responsible for early defense against infections and it is believed that the interferons (IFNs) constitute the first line of defense against viruses. Here we identify an innate antiviral pathway that works at epithelial surfaces before the IFNs. The pathway is activated independently of known innate sensors of viral infections through a mechanism dependent on viral O-linked glycans, which induce CXCR3 chemokines and stimulate antiviral activity in a manner dependent on neutrophils. This study therefore identifies a previously unknown layer of antiviral defense that exerts its action on epithelial surfaces before the classical IFN response is operative.


Asunto(s)
Inmunidad Innata , Interferones/metabolismo , Membrana Mucosa/inmunología , Membrana Mucosa/metabolismo , Virosis/inmunología , Virosis/metabolismo , Animales , Línea Celular , Quimiocina CXCL10/biosíntesis , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Glicosilación , Herpes Simple/genética , Herpes Simple/inmunología , Herpes Simple/metabolismo , Herpes Simple/virología , Herpesvirus Humano 2/inmunología , Humanos , Interferones/genética , Ligandos , Ratones , Ratones Noqueados , Membrana Mucosa/virología , Neutrófilos/inmunología , Neutrófilos/metabolismo , Polisacáridos/inmunología , Receptores CXCR3/deficiencia , Receptores CXCR3/metabolismo , Vagina/inmunología , Vagina/metabolismo , Vagina/virología , Proteínas del Envoltorio Viral/inmunología , Proteínas del Envoltorio Viral/metabolismo , Carga Viral , Virosis/virología
5.
EMBO J ; 42(19): e113118, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37646198

RESUMEN

Neurotropic viruses, including herpes simplex virus (HSV) types 1 and 2, have the capacity to infect neurons and can cause severe diseases. This is associated with neuronal cell death, which may contribute to morbidity or even mortality if the infection is not controlled. However, the mechanistic details of HSV-induced neuronal cell death remain enigmatic. Here, we report that lytic HSV-2 infection of human neuron-like SH-SY5Y cells and primary human and murine brain cells leads to cell death mediated by gasdermin E (GSDME). HSV-2-induced GSDME-mediated cell death occurs downstream of replication-induced endoplasmic reticulum stress driven by inositol-requiring kinase 1α (IRE1α), leading to activation of caspase-2, cleavage of the pro-apoptotic protein BH3-interacting domain death agonist (BID), and mitochondria-dependent activation of caspase-3. Finally, necrotic neurons released alarmins, which activated inflammatory responses in human iPSC-derived microglia. In conclusion, lytic HSV infection in neurons activates an ER stress-driven pathway to execute GSDME-mediated cell death and promote inflammation.

6.
Nat Methods ; 21(4): 703-711, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38383746

RESUMEN

To identify and extract naturalistic behavior, two methods have become popular: supervised and unsupervised. Each approach carries its own strengths and weaknesses (for example, user bias, training cost, complexity and action discovery), which the user must consider in their decision. Here, an active-learning platform, A-SOiD, blends these strengths, and in doing so, overcomes several of their inherent drawbacks. A-SOiD iteratively learns user-defined groups with a fraction of the usual training data, while attaining expansive classification through directed unsupervised classification. In socially interacting mice, A-SOiD outperformed standard methods despite requiring 85% less training data. Additionally, it isolated ethologically distinct mouse interactions via unsupervised classification. We observed similar performance and efficiency using nonhuman primate and human three-dimensional pose data. In both cases, the transparency in A-SOiD's cluster definitions revealed the defining features of the supervised classification through a game-theoretic approach. To facilitate use, A-SOiD comes as an intuitive, open-source interface for efficient segmentation of user-defined behaviors and discovered sub-actions.


Asunto(s)
Aprendizaje , Aprendizaje Basado en Problemas , Humanos , Animales , Ratones
7.
Proc Natl Acad Sci U S A ; 121(18): e2404188121, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38657045

RESUMEN

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death. HCC incidence is on the rise, while treatment options remain limited. Thus, a better understanding of the molecular pathways involved in HCC development has become a priority to guide future therapies. While previous studies implicated the Activator Protein-1 (AP-1) (Fos/Jun) transcription factor family members c-Fos and c-Jun in HCC formation, the contribution of Fos-related antigens (Fra-) 1 and 2 is unknown. Here, we show that hepatocyte-restricted expression of a single chain c-Jun~Fra-2 protein, which functionally mimics the c-Jun/Fra-2 AP-1 dimer, results in spontaneous HCC formation in c-Jun~Fra-2hep mice. Several hallmarks of human HCC, such as cell cycle dysregulation and the expression of HCC markers are observed in liver tumors arising in c-Jun~Fra-2hep mice. Tumorigenesis occurs in the context of mild inflammation, low-grade fibrosis, and Pparγ-driven dyslipidemia. Subsequent analyses revealed increased expression of c-Myc, evidently under direct regulation by AP-1 through a conserved distal 3' enhancer. Importantly, c-Jun~Fra-2-induced tumors revert upon switching off transgene expression, suggesting oncogene addiction to the c-Jun~Fra-2 transgene. Tumors escaping reversion maintained c-Myc and c-Myc target gene expression, likely due to increased c-Fos. Interfering with c-Myc in established tumors using the Bromodomain and Extra-Terminal motif inhibitor JQ-1 diminished liver tumor growth in c-Jun~Fra-2 mutant mice. Thus, our data establish c-Jun~Fra-2hep mice as a model to study liver tumorigenesis and identify the c-Jun/Fra-2-Myc interaction as a potential target to improve HCC patient stratification and/or therapy.


Asunto(s)
Carcinoma Hepatocelular , Antígeno 2 Relacionado con Fos , Neoplasias Hepáticas , Proteínas Proto-Oncogénicas c-fos , Proteínas Proto-Oncogénicas c-jun , Proteínas Proto-Oncogénicas c-myc , Factor de Transcripción AP-1 , Animales , Factor de Transcripción AP-1/metabolismo , Factor de Transcripción AP-1/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Ratones , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-fos/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Proteínas Proto-Oncogénicas c-jun/metabolismo , Antígeno 2 Relacionado con Fos/metabolismo , Antígeno 2 Relacionado con Fos/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Humanos , Hepatocitos/metabolismo , Multimerización de Proteína , Regulación Neoplásica de la Expresión Génica , Ratones Transgénicos
8.
Proc Natl Acad Sci U S A ; 121(25): e2322475121, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38857404

RESUMEN

Low temperatures and cooling agents like menthol induce cold sensation by activating the peripheral cold receptors TRPM8 and TRPA1, cation channels belonging to the TRP channel family, while the reduction of potassium currents provides an additional and/or synergistic mechanism of cold sensation. Despite extensive studies over the past decades to identify the molecular receptors that mediate thermosensation, cold sensation is still not fully understood and many cold-sensitive peripheral neurons do not express the well-established cold sensor TRPM8. We found that the voltage-gated potassium channel KCNQ1 (Kv7.1), which is defective in cardiac LQT1 syndrome, is, in addition to its known function in the heart, a highly relevant and sex-specific sensor of moderately cold temperatures. We found that KCNQ1 is expressed in skin and dorsal root ganglion neurons, is sensitive to menthol and cooling agents, and is highly sensitive to moderately cold temperatures, in a temperature range at which TRPM8 is not thermosensitive. C-fiber recordings from KCNQ1-/- mice displayed altered action potential firing properties. Strikingly, only male KCNQ1-/- mice showed substantial deficits in cold avoidance at moderately cold temperatures, with a strength of the phenotype similar to that observed in TRPM8-/- animals. While sex-dependent differences in thermal sensitivity have been well documented in humans and mice, KCNQ1 is the first gene reported to play a role in sex-specific temperature sensation. Moreover, we propose that KCNQ1, together with TRPM8, is a key instrumentalist that orchestrates the range and intensity of cold sensation.


Asunto(s)
Frío , Canal de Potasio KCNQ1 , Animales , Masculino , Femenino , Ratones , Canal de Potasio KCNQ1/metabolismo , Canal de Potasio KCNQ1/genética , Ratones Noqueados , Ganglios Espinales/metabolismo , Sensación Térmica/fisiología , Canales Catiónicos TRPM/metabolismo , Canales Catiónicos TRPM/genética , Ratones Endogámicos C57BL , Potenciales de Acción/fisiología , Caracteres Sexuales , Mentol/farmacología
9.
Nucleic Acids Res ; 51(18): 10059-10074, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37678882

RESUMEN

Implementation of therapeutic in vivo gene editing using CRISPR/Cas relies on potent delivery of gene editing tools. Administration of ribonucleoprotein (RNP) complexes consisting of Cas protein and single guide RNA (sgRNA) offers short-lived editing activity and safety advantages over conventional viral and non-viral gene and RNA delivery approaches. By engineering lentivirus-derived nanoparticles (LVNPs) to facilitate RNP delivery, we demonstrate effective administration of SpCas9 as well as SpCas9-derived base and prime editors (BE/PE) leading to gene editing in recipient cells. Unique Gag/GagPol protein fusion strategies facilitate RNP packaging in LVNPs, and refinement of LVNP stoichiometry supports optimized LVNP yield and incorporation of therapeutic payload. We demonstrate near instantaneous target DNA cleavage and complete RNP turnover within 4 days. As a result, LVNPs provide high on-target DNA cleavage and lower levels of off-target cleavage activity compared to standard RNP nucleofection in cultured cells. LVNPs accommodate BE/sgRNA and PE/epegRNA RNPs leading to base editing with reduced bystander editing and prime editing without detectable indel formation. Notably, in the mouse eye, we provide the first proof-of-concept for LVNP-directed in vivo gene disruption. Our findings establish LVNPs as promising vehicles for delivery of RNPs facilitating donor-free base and prime editing without formation of double-stranded DNA breaks.

10.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35064078

RESUMEN

Prostate-specific membrane antigen (PSMA) is highly overexpressed in most prostate cancers and is clinically visualized using PSMA-specific probes incorporating glutamate-ureido-lysine (GUL). PSMA is effectively absent from certain high-mortality, treatment-resistant subsets of prostate cancers, such as neuroendocrine prostate cancer (NEPC); however, GUL-based PSMA tracers are still reported to have the potential to identify NEPC metastatic tumors. These probes may bind unknown proteins associated with PSMA-suppressed cancers. We have identified the up-regulation of PSMA-like aminopeptidase NAALADaseL and the metabotropic glutamate receptors (mGluRs) in PSMA-suppressed prostate cancers and find that their expression levels inversely correlate with PSMA expression and are associated with GUL-based radiotracer uptake. Furthermore, we identify that NAALADaseL and mGluR expression correlates with a unique cell cycle signature. This provides an opportunity for the future study of the biology of NEPC and potential therapeutic directions. Computationally predicting that GUL-based probes bind well to these targets, we designed and synthesized a fluorescent PSMA tracer to investigate these proteins in vitro, where it shows excellent affinity for PSMA, NAALADaseL, and specific mGluRs associated with poor prognosis.


Asunto(s)
Antígenos de Superficie/metabolismo , Glutamato Carboxipeptidasa II/metabolismo , Glutamatos , Lisina , Sondas Moleculares , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/metabolismo , Urea , Animales , Antígenos de Superficie/química , Sitios de Unión , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Técnica del Anticuerpo Fluorescente , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/química , Expresión Génica , Glutamato Carboxipeptidasa II/química , Glutamatos/química , Humanos , Inmunohistoquímica , Lisina/química , Masculino , Ratones , Modelos Moleculares , Conformación Molecular , Imagen Molecular/métodos , Sondas Moleculares/química , Neoplasias de la Próstata/genética , Unión Proteica , Receptores de Ácido Kaínico/genética , Receptores de Ácido Kaínico/metabolismo , Relación Estructura-Actividad , Urea/análogos & derivados , Urea/química
11.
PLoS Genet ; 18(9): e1010356, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36137075

RESUMEN

Rare variants in ten genes have been reported to cause Mendelian sleep conditions characterised by extreme sleep duration or timing. These include familial natural short sleep (ADRB1, DEC2/BHLHE41, GRM1 and NPSR1), advanced sleep phase (PER2, PER3, CRY2, CSNK1D and TIMELESS) and delayed sleep phase (CRY1). The association of variants in these genes with extreme sleep conditions were usually based on clinically ascertained families, and their effects when identified in the population are unknown. We aimed to determine the effects of these variants on sleep traits in large population-based cohorts. We performed genetic association analysis of variants previously reported to be causal for Mendelian sleep and circadian conditions. Analyses were performed using 191,929 individuals with data on sleep and whole-exome or genome-sequence data from 4 population-based studies: UK Biobank, FINRISK, Health-2000-2001, and the Multi-Ethnic Study of Atherosclerosis (MESA). We identified sleep disorders from self-report, hospital and primary care data. We estimated sleep duration and timing measures from self-report and accelerometery data. We identified carriers for 10 out of 12 previously reported pathogenic variants for 8 of the 10 genes. They ranged in frequency from 1 individual with the variant in CSNK1D to 1,574 individuals with a reported variant in the PER3 gene in the UK Biobank. No carriers for variants reported in NPSR1 or PER2 were identified. We found no association between variants analyzed and extreme sleep or circadian phenotypes. Using sleep timing as a proxy measure for sleep phase, only PER3 and CRY1 variants demonstrated association with earlier and later sleep timing, respectively; however, the magnitude of effect was smaller than previously reported (sleep midpoint ~7 mins earlier and ~5 mins later, respectively). We also performed burden tests of protein truncating (PTVs) or rare missense variants for the 10 genes. Only PTVs in PER2 and PER3 were associated with a relevant trait (for example, 64 individuals with a PTV in PER2 had an odds ratio of 4.4 for being "definitely a morning person", P = 4x10-8; and had a 57-minute earlier midpoint sleep, P = 5x10-7). Our results indicate that previously reported variants for Mendelian sleep and circadian conditions are often not highly penetrant when ascertained incidentally from the general population.


Asunto(s)
Ritmo Circadiano , Trastornos del Sueño-Vigilia , Ritmo Circadiano/genética , Humanos , Fenotipo , Receptores Acoplados a Proteínas G/genética , Sueño/genética , Trastornos del Sueño-Vigilia/genética
12.
Med Res Rev ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842004

RESUMEN

For the last two decades, the aromatic aldehyde 5-hydroxymethyl-furfural (5-HMF) has been the subject of several investigations for its pharmacologic potential. In 2004, the Safo group reported that 5-HMF has potent antisickling activity by targeting and ameliorating the primary pathophysiology of hypoxia-induced sickling of erythrocytes (red blood cells [RBC]). Following the encouraging outcome of the preclinical and phase I/II clinical studies of 5-HMF for the treatment of sickle cell disease (SCD), there have been multiple studies suggesting 5-HMF has several other biological or pharmacologic activities, including anti-allergic, antioxidant, anti-hypoxic, anti-ischemic, cognitive improvement, anti-tyrosinase, anti-proliferation, cytoprotective, and anti-inflammatory activities. The wide range of its effects makes 5-HMF a potential candidate for treating a variety of diseases including cognitive disorders, gout, allergic disorders, anemia, hypoxia, cancers, ischemia, hemorrhagic shock, liver fibrosis, and oxidative injury. Several of these therapeutic claims are currently under investigation and, while promising, vary in terms of the strength of their evidence. This review presents the research regarding the therapeutic potential of 5-HMF in addition to its sources, physicochemical properties, safety, absorption, distribution, metabolism, and excretion (ADME) profiles.

13.
Diabetologia ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38935155

RESUMEN

AIMS/HYPOTHESIS: Both short and long sleep durations have been linked to higher diabetes risk. However, sleep duration may vary over time, and there has been limited research focusing on individual sleep trajectories and diabetes risk. There are substantial racial disparities in both sleep health and diabetes risk in the USA. Thus, it is important to understand the role of suboptimal sleep patterns in diabetes risk in different racial groups. METHODS: We assessed long-term trajectories of sleep duration and incident diabetes in 22,285 Black adults (mean age ± SD, 51.1 ± 8.2 years; 64.8% women) and 13,737 White adults (mean age ± SD, 54.4 ± 9.0 years; 63.8% women) enrolled in the Southern Community Cohort Study. Nine sleep trajectories were derived based on self-reported sleep duration at baseline and after a mean of 5 years of follow-up: normal-normal (reference), short-normal, normal-short, short-short, long-normal, normal-long, long-long, long-short and short-long. Diabetes was reported using a validated questionnaire. Multivariable-adjusted logistic regression was used to determine relationships between sleep trajectories and incident diabetes. RESULTS: When compared with the normal-normal trajectory, suboptimal sleep trajectories were associated with higher likelihoods of developing diabetes (OR; 95% CI: short-normal 1.19; 1.09, 1.31; normal-short 1.14; 1.02, 1.27; short-short 1.17; 1.07, 1.28; long-normal 1.13; 0.98, 1.30; normal-long 1.16; 1.00, 1.34; long-long 1.23; 1.02, 1.48; long-short 1.45; 1.19, 1.77; short-long 1.51; 1.28, 1.77). Stratified analyses by race and socioeconomic status (i.e. education and household income) showed that most suboptimal sleep trajectories were consistently associated with incident diabetes in all sociodemographic subgroups. We also noted potential interaction with race and education for several sleep trajectories (i.e. short-long and normal-short with race; long-long and short-short with education). CONCLUSIONS/INTERPRETATION: Adults with suboptimal sleep duration trajectories are more likely to develop incident diabetes. Future research is needed to study how sociodemographic factors modulate this relationship.

14.
J Am Chem Soc ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38838087

RESUMEN

For the excitation to a repulsive state of a diatomic molecule, one expects a single broad peak in the photodissociation spectrum. For Zn2+, however, two peaks for the spin- and symmetry-allowed A2Σg+ ← X2Σu+ transition are observed. A detailed quantum-chemical analysis reveals pronounced multiconfigurational character of the A2Σg+ state. The σg(4s)2σg(4p) configuration with bond order 1.5 dominates at short distances, while the repulsive σg(4s)σu*(4s)2 configuration with bond order -0.5 wins over with increasing bond length. The two excited-state configurations contribute with opposite signs to the transition dipole moment, which reaches zero near the equilibrium distance. This local minimum of the oscillator strength is responsible for the pronounced dip in the photodissociation spectrum, which is thus the spectroscopic signature of the multiconfigurational character of the A2Σg+ state.

15.
Am J Transplant ; 24(1): 30-36, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37633449

RESUMEN

De novo membranous nephropathy (dnMN) is an uncommon immune complex-mediated late complication of human kidney allografts that causes proteinuria. We report here the first case of dnMN in a pig-to-baboon kidney xenograft. The donor was a double knockout (GGTA1 and ß4GalNT1) genetically engineered pig with a knockout of the growth hormone receptor and addition of 6 human transgenes (hCD46, hCD55, hTBM, hEPCR, hHO1, and hCD47). The recipient developed proteinuria at 42 days posttransplant, which progressively rose to the nephrotic-range at 106 days, associated with an increase in serum antidonor IgG. Kidney biopsies showed antibody-mediated rejection (AMR) with C4d and thrombotic microangiopathy that eventually led to graft failure at 120 days. In addition to AMR, the xenograft had diffuse, global granular deposition of C4d and IgG along the glomerular basement membrane on days 111 and 120. Electron microscopy showed extensive amorphous subepithelial electron-dense deposits with intervening spikes along the glomerular basement membrane. These findings, in analogy to human renal allografts, are interpreted as dnMN in the xenograft superimposed on AMR. The target was not identified but is hypothesized to be a pig xenoantigen expressed on podocytes. Whether dnMN will be a significant problem in other longer-term xenokidneys remains to be determined.


Asunto(s)
Glomerulonefritis Membranosa , Enfermedades Renales , Trasplante de Riñón , Humanos , Porcinos , Animales , Glomerulonefritis Membranosa/etiología , Trasplante de Riñón/efectos adversos , Xenoinjertos , Riñón/patología , Enfermedades Renales/patología , Proteinuria/etiología , Inmunoglobulina G , Rechazo de Injerto/patología
16.
Ann Surg ; 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38275104

RESUMEN

BACKGROUND: Recent retrospective studies suggest a role for distinct microbiota in the perioperative morbidity and mortality of pancreatic head resections. OBJECTIVE: We aimed to prospectively investigate the microbial colonization of critical operative sites of pancreatic head resections to identify microbial stratification factors for surgical and long-term oncologic outcomes. METHODS: Prospective biomarker study applying 16S rRNA sequencing and microbial culturing to samples collected from various sites of the GI tract and surgical sites of patients during pancreatic head resections at a German single high-volume pancreatic center. RESULTS: A total of 101 patients were included (38 non-cancer, 63 cancer patients [50 PDAC patients]) in the study. In a first data analysis series, 16S rRNA sequencing data were utilized from 96 patients to assess associations of microbiome profiles with clinical parameters and outcomes. In general, microbiome composition varied according to sampling site, cancer, age or preoperative ERCP intervention, notably for the bile microbiome. In the PDAC subcohort, compositional variance of the bile or periampullary microbiome was significantly associated with postoperative complications such as ICU admission; on a taxonomic level we observed Enterococcus spp. to be significantly more abundant in patients developing deep or organ-space surgical site infections (SSI). Elevated Enterococcus relative abundances in the upper GI tract, in turn, were associated with 6-months mortality rates. In a second step, we focused on microbiological cultures collected from bile aspirates during surgery and investigated associations with perioperative complications and long-term survival. Notably, Enterococcus spp. were among the most prevalent pathobiont isolates observed in cancer patient bile specimens that were associated with severe SSIs, and thereby elevated mortality rates up to 24 months. Clinically relevant postoperative pancreatic fistulas or severe SSI were found as other major variables determining short-term mortality in this cancer patient cohort. In the context of adverse microbiological factors, a preoperative ERCP was also observed to segregate long-term survival, and it appeared to interact with the presence of Enterococcus spp. as highest mortality rates were observed in PDAC patients with both preoperative ERCP and presence of E. faecalis in bile aspirates. CONCLUSIONS: The presence of Enterococcus spp. in bile ducts of PDAC patients undergoing pancreatic surgery represents a significant risk factor for perioperative infections and, thereby, elevated postoperative and long-term mortality. This finding supports previous data on the use of the antibiotic drug piperacillin-tazobactam as appropriate perioperative antibiotic prophylaxis for preventing adverse outcomes after pancreatoduodenectomy.

17.
Crit Care Med ; 52(5): 775-785, 2024 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-38180092

RESUMEN

OBJECTIVES: To determine if near-infrared spectroscopy measuring cerebral regional oxygen saturation (crS o2 ) during cardiopulmonary resuscitation is associated with return of spontaneous circulation (ROSC) and survival to hospital discharge (SHD) in children. DESIGN: Multicenter, observational study. SETTING: Three hospitals in the pediatric Resuscitation Quality (pediRES-Q) collaborative from 2015 to 2022. PATIENTS: Children younger than 18 years, gestational age 37 weeks old or older with in-hospital cardiac arrest (IHCA) receiving cardiopulmonary resuscitation greater than or equal to 1 minute and intra-arrest crS o2 monitoring. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Primary outcome was ROSC greater than or equal to 20 minutes without extracorporeal membrane oxygenation. Secondary outcomes included SHD and favorable neurologic outcome (FNO) (Pediatric Cerebral Performance Category 1-2 or no change from prearrest). Among 3212 IHCA events (index and nonindex), 123 met inclusion criteria in 93 patients. Median age was 0.3 years (0.1-1.4 yr) and 31% (38/123) of the cardiopulmonary resuscitation events occurred in patients with cyanotic heart disease. Median cardiopulmonary resuscitation duration was 8 minutes (3-28 min) and ROSC was achieved in 65% (80/123). For index events, SHD was achieved in 59% (54/91) and FNO in 41% (37/91). We determined the association of median intra-arrest crS o2 and percent of crS o2 values above a priori thresholds during the: 1) entire cardiopulmonary resuscitation event, 2) first 5 minutes, and 3) last 5 minutes with ROSC, SHD, and FNO. Higher crS o2 for the entire cardiopulmonary resuscitation event, first 5 minutes, and last 5 minutes were associated with higher likelihood of ROSC, SHD, and FNO. In multivariable analysis of the infant group (age < 1 yr), higher crS o2 was associated with ROSC (odds ratio [OR], 1.06; 95% CI, 1.03-1.10), SHD (OR, 1.04; 95% CI, 1.01-1.07), and FNO (OR, 1.05; 95% CI, 1.02-1.08) after adjusting for presence of cyanotic heart disease. CONCLUSIONS: Higher crS o2 during pediatric IHCA was associated with increased rate of ROSC, SHD, and FNO. Intra-arrest crS o2 may have a role as a real-time, noninvasive predictor of ROSC.


Asunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco , Humanos , Lactante , Reanimación Cardiopulmonar/métodos , Circulación Cerebrovascular , Paro Cardíaco/terapia , Hospitales Pediátricos , Oximetría
18.
Ann Rheum Dis ; 83(3): 274-276, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-37821213

RESUMEN

Animal models of post traumatic osteoarthritis have shown many promising treatments for disease, but human trials have mostly failed to identify effective treatments. This viewpoint suggests that the frequent failure of drug and treatment development in osteoarthritis is due, in part, to the advanced stage of disease of patients in trials and suggests that mirroring the animal model approach might be more successful. It suggests a path forward by enriching trial enrollees with those likely to develop post traumatic OA quickly.


Asunto(s)
Osteoartritis , Animales , Humanos , Osteoartritis/tratamiento farmacológico , Resultado del Tratamiento
19.
Ann Neurol ; 93(6): 1145-1157, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36808743

RESUMEN

OBJECTIVE: Delirium is a complex neurocognitive syndrome suspected to be bidirectionally linked to dementia. Circadian rhythm disturbances likely contribute to dementia pathogenesis, but whether these disturbances are related to delirium risk and progression to all-cause dementia is unknown. METHODS: We analyzed continuous actigraphy data from 53,417 middle-aged or older UK Biobank participants during a median 5 years of follow-up. Four measures were used to characterize the 24-hour daily rest-activity rhythms (RARs): normalized amplitude, acrophase representing the peak activity time, interdaily stability, and intradaily variability (IV) for fragmentation of the rhythm. Cox proportional hazards models examined whether RARs predicted incident delirium (n = 551) and progression to dementia (n = 61). RESULTS: Suppressed 24-hour amplitude, lowest (Q1) versus highest (Q4) quartile (hazard ratio [HR]Q1 vs Q4 = 1.94, 95% confidence interval [CI] = 1.53-2.46, p < 0.001), and more fragmented (higher IV: HRQ4 vs Q1 = 1.49, 95% CI = 1.18-1.88, p < 0.001) rhythms predicted higher delirium risk, after adjusting for age, sex, education, cognitive performance, sleep duration/disturbances, and comorbidities. In those free from dementia, each hour of delayed acrophase was associated with delirium risk (HR = 1.13, 95% CI = 1.04-1.23, p = 0.003). Suppressed 24-hour amplitude was associated with increased risk of progression from delirium to new onset dementia (HR = 1.31, 95% CI = 1.03-1.67, p = 0.03 for each 1-standard deviation decrease). INTERPRETATION: Twenty-four-hour daily RAR suppression, fragmentation, and potentially delayed acrophase were associated with delirium risk. Subsequent progression to dementia was more likely in delirium cases with suppressed rhythms. The presence of RAR disturbances before delirium and prior to progression to dementia suggests that these disturbances may predict higher risk and be involved in early disease pathogenesis. ANN NEUROL 2023;93:1145-1157.


Asunto(s)
Delirio , Demencia , Trastornos del Sueño-Vigilia , Persona de Mediana Edad , Humanos , Sueño , Ritmo Circadiano , Descanso , Actigrafía , Demencia/etiología , Delirio/etiología
20.
Sex Transm Infect ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38964841

RESUMEN

BACKGROUND: While the COVID-19 pandemic disrupted HIV preventative services in sub-Saharan Africa, little is known about the specific impacts the pandemic has had on men who have sex with men (MSM) in Kenya. METHODS: Data were from an HIV self-testing intervention implemented in Kisumu, Mombasa and Kiambu counties in Kenya. Baseline data collection took place from May to July 2019, and endline in August-October 2020, coinciding with the lifting of some COVID-19 mitigation measures. Using endline data, this study characterised the impact the pandemic had on participants' risk behaviours, experience of violence and behaviours related to HIV. Logistic regression was used to understand factors related to changes in risk behaviours and experiences of violence; adjusted AORs (AORs) and 95% CIs are reported. RESULTS: Median age was 24 years (IQR: 21-27). Most respondents (93.9%) reported no change or a decrease in the number of sexual partners (median number of male sexual partners: 2, IQR: 2-4). Some participants reported an increase in alcohol (10%) and drug (16%) consumption, while 40% and 28% reported decreases in alcohol and drug consumption, respectively. Approximately 3% and 10% reported an increase in violence from intimate partners and police/authorities, respectively. Compared with those with primary education, those with post-secondary education were 60% less likely to report an increase in the number of male sexual partners per week (AOR: 0.4, 95% CI: 0.2 to 0.9), while those who were HIV positive were at twofold the odds of reporting an increase or sustained levels of violence from intimate partners (AOR: 2.0, 95% CI: 1.1 to 4.0). CONCLUSION: The results of this study demonstrate heterogeneity in participants' access to preventative HIV and clinical care services in Kenya after the onset of the COVID-19 epidemic. These results indicate the importance of responding to specific needs of MSM and adapting programmes during times of crisis.

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