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1.
Cell ; 183(7): 1986-2002.e26, 2020 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-33333022

RESUMEN

Serotonin plays a central role in cognition and is the target of most pharmaceuticals for psychiatric disorders. Existing drugs have limited efficacy; creation of improved versions will require better understanding of serotonergic circuitry, which has been hampered by our inability to monitor serotonin release and transport with high spatial and temporal resolution. We developed and applied a binding-pocket redesign strategy, guided by machine learning, to create a high-performance, soluble, fluorescent serotonin sensor (iSeroSnFR), enabling optical detection of millisecond-scale serotonin transients. We demonstrate that iSeroSnFR can be used to detect serotonin release in freely behaving mice during fear conditioning, social interaction, and sleep/wake transitions. We also developed a robust assay of serotonin transporter function and modulation by drugs. We expect that both machine-learning-guided binding-pocket redesign and iSeroSnFR will have broad utility for the development of other sensors and in vitro and in vivo serotonin detection, respectively.


Asunto(s)
Evolución Molecular Dirigida , Aprendizaje Automático , Serotonina/metabolismo , Algoritmos , Secuencia de Aminoácidos , Amígdala del Cerebelo/fisiología , Animales , Conducta Animal , Sitios de Unión , Encéfalo/metabolismo , Células HEK293 , Humanos , Cinética , Modelos Lineales , Ratones , Ratones Endogámicos C57BL , Fotones , Unión Proteica , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Sueño/fisiología , Vigilia/fisiología
2.
Immunity ; 54(6): 1290-1303.e7, 2021 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-34022127

RESUMEN

Dissecting the evolution of memory B cells (MBCs) against SARS-CoV-2 is critical for understanding antibody recall upon secondary exposure. Here, we used single-cell sequencing to profile SARS-CoV-2-reactive B cells in 38 COVID-19 patients. Using oligo-tagged antigen baits, we isolated B cells specific to the SARS-CoV-2 spike, nucleoprotein (NP), open reading frame 8 (ORF8), and endemic human coronavirus (HCoV) spike proteins. SARS-CoV-2 spike-specific cells were enriched in the memory compartment of acutely infected and convalescent patients several months post symptom onset. With severe acute infection, substantial populations of endemic HCoV-reactive antibody-secreting cells were identified and possessed highly mutated variable genes, signifying preexisting immunity. Finally, MBCs exhibited pronounced maturation to NP and ORF8 over time, especially in older patients. Monoclonal antibodies against these targets were non-neutralizing and non-protective in vivo. These findings reveal antibody adaptation to non-neutralizing intracellular antigens during infection, emphasizing the importance of vaccination for inducing neutralizing spike-specific MBCs.


Asunto(s)
Anticuerpos Antivirales/inmunología , Formación de Anticuerpos/inmunología , Linfocitos B/inmunología , COVID-19/inmunología , Interacciones Huésped-Patógeno/inmunología , Epítopos Inmunodominantes/inmunología , SARS-CoV-2/inmunología , Anticuerpos Neutralizantes/inmunología , Formación de Anticuerpos/genética , Linfocitos B/metabolismo , Biología Computacional/métodos , Reacciones Cruzadas/inmunología , Mapeo Epitopo , Femenino , Perfilación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Interacciones Huésped-Patógeno/genética , Humanos , Epítopos Inmunodominantes/genética , Memoria Inmunológica , Masculino , Pruebas de Neutralización , Análisis de la Célula Individual/métodos , Glicoproteína de la Espiga del Coronavirus/inmunología , Transcriptoma
3.
Immunity ; 53(6): 1230-1244.e5, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33096040

RESUMEN

Polyreactivity is the ability of a single antibody to bind to multiple molecularly distinct antigens and is a common feature of antibodies induced upon pathogen exposure. However, little is known about the role of polyreactivity during anti-influenza virus antibody responses. By analyzing more than 500 monoclonal antibodies (mAbs) derived from B cells induced by numerous influenza virus vaccines and infections, we found mAbs targeting conserved neutralizing influenza virus hemagglutinin epitopes were polyreactive. Polyreactive mAbs were preferentially induced by novel viral exposures due to their broad viral binding breadth. Polyreactivity augmented mAb viral binding strength by increasing antibody flexibility, allowing for adaption to imperfectly conserved epitopes. Lastly, we found affinity-matured polyreactive B cells were typically derived from germline polyreactive B cells that were preferentially selected to participate in B cell responses over time. Together, our data reveal that polyreactivity is a beneficial feature of antibodies targeting conserved epitopes.


Asunto(s)
Linfocitos B/inmunología , Anticuerpos ampliamente neutralizantes/inmunología , Orthomyxoviridae/inmunología , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/inmunología , Afinidad de Anticuerpos , Anticuerpos ampliamente neutralizantes/genética , Reacciones Cruzadas , Epítopos de Linfocito B/inmunología , Genes de Inmunoglobulinas , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Humanos , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunología , Gripe Humana/prevención & control , Gripe Humana/virología , Orthomyxoviridae/clasificación , Dominios Proteicos , Hipermutación Somática de Inmunoglobulina
4.
Nature ; 602(7896): 314-320, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34942633

RESUMEN

Broadly neutralizing antibodies that target epitopes of haemagglutinin on the influenza virus have the potential to provide near universal protection against influenza virus infection1. However, viral mutants that escape broadly neutralizing antibodies have been reported2,3. The identification of broadly neutralizing antibody classes that can neutralize viral escape mutants is critical for universal influenza virus vaccine design. Here we report a distinct class of broadly neutralizing antibodies that target a discrete membrane-proximal anchor epitope of the haemagglutinin stalk domain. Anchor epitope-targeting antibodies are broadly neutralizing across H1 viruses and can cross-react with H2 and H5 viruses that are a pandemic threat. Antibodies that target this anchor epitope utilize a highly restricted repertoire, which encodes two public binding motifs that make extensive contacts with conserved residues in the fusion peptide. Moreover, anchor epitope-targeting B cells are common in the human memory B cell repertoire and were recalled in humans by an oil-in-water adjuvanted chimeric haemagglutinin vaccine4,5, which is a potential universal influenza virus vaccine. To maximize protection against seasonal and pandemic influenza viruses, vaccines should aim to boost this previously untapped source of broadly neutralizing antibodies that are widespread in the human memory B cell pool.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Anticuerpos ampliamente neutralizantes , Epítopos , Glicoproteínas Hemaglutininas del Virus de la Influenza , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Anticuerpos ampliamente neutralizantes/inmunología , Epítopos/química , Epítopos/inmunología , Glicoproteínas Hemaglutininas del Virus de la Influenza/química , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Humanos , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunología , Gripe Humana/prevención & control , Gripe Humana/virología , Células B de Memoria/inmunología
5.
Cereb Cortex ; 34(1)2024 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-37885155

RESUMEN

Normal cortical growth and the resulting folding patterns are crucial for normal brain function. Although cortical development is largely influenced by genetic factors, environmental factors in fetal life can modify the gene expression associated with brain development. As the placenta plays a vital role in shaping the fetal environment, affecting fetal growth through the exchange of oxygen and nutrients, placental oxygen transport might be one of the environmental factors that also affect early human cortical growth. In this study, we aimed to assess the placental oxygen transport during maternal hyperoxia and its impact on fetal brain development using MRI in identical twins to control for genetic and maternal factors. We enrolled 9 pregnant subjects with monochorionic diamniotic twins (30.03 ± 2.39 gestational weeks [mean ± SD]). We observed that the fetuses with slower placental oxygen delivery had reduced volumetric and surface growth of the cerebral cortex. Moreover, when the difference between placenta oxygen delivery increased between the twin pairs, sulcal folding patterns were more divergent. Thus, there is a significant relationship between placental oxygen transport and fetal brain cortical growth and folding in monochorionic twins.


Asunto(s)
Placenta , Gemelos Monocigóticos , Femenino , Humanos , Embarazo , Desarrollo Fetal , Retardo del Crecimiento Fetal/metabolismo , Oxígeno/metabolismo , Placenta/diagnóstico por imagen , Placenta/metabolismo
6.
Cereb Cortex ; 34(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38602735

RESUMEN

Developmental changes that occur before birth are thought to be associated with the development of autism spectrum disorders. Identifying anatomical predictors of early brain development may contribute to our understanding of the neurobiology of autism spectrum disorders and allow for earlier and more effective identification and treatment of autism spectrum disorders. In this study, we used retrospective clinical brain magnetic resonance imaging data from fetuses who were diagnosed with autism spectrum disorders later in life (prospective autism spectrum disorders) in order to identify the earliest magnetic resonance imaging-based regional volumetric biomarkers. Our results showed that magnetic resonance imaging-based autism spectrum disorder biomarkers can be found as early as in the fetal period and suggested that the increased volume of the insular cortex may be the most promising magnetic resonance imaging-based fetal biomarker for the future emergence of autism spectrum disorders, along with some additional, potentially useful changes in regional volumes and hemispheric asymmetries.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Humanos , Trastorno Autístico/diagnóstico por imagen , Trastorno del Espectro Autista/diagnóstico por imagen , Estudios Prospectivos , Estudios Retrospectivos , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Biomarcadores
7.
Cereb Cortex ; 34(2)2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38365268

RESUMEN

Cleft lip/palate is a common orofacial malformation that often leads to speech/language difficulties as well as developmental delays in affected children, despite surgical repair. Our understanding of brain development in these children is limited. This study aimed to analyze prenatal brain development in fetuses with cleft lip/palate and controls. We examined in utero MRIs of 30 controls and 42 cleft lip/palate fetal cases and measured regional brain volumes. Cleft lip/palate was categorized into groups A (cleft lip or alveolus) and B (any combination of clefts involving the primary and secondary palates). Using a repeated-measures regression model with relative brain hemisphere volumes (%), and after adjusting for multiple comparisons, we did not identify significant differences in regional brain growth between group A and controls. Group B clefts had significantly slower weekly cerebellar growth compared with controls. We also observed divergent brain growth in transient brain structures (cortical plate, subplate, ganglionic eminence) within group B clefts, depending on severity (unilateral or bilateral) and defect location (hemisphere ipsilateral or contralateral to the defect). Further research is needed to explore the association between regional fetal brain growth and cleft lip/palate severity, with the potential to inform early neurodevelopmental biomarkers and personalized diagnostics.


Asunto(s)
Labio Leporino , Fisura del Paladar , Femenino , Niño , Embarazo , Humanos , Labio Leporino/diagnóstico por imagen , Labio Leporino/cirugía , Fisura del Paladar/diagnóstico por imagen , Fisura del Paladar/cirugía , Encéfalo/diagnóstico por imagen , Encéfalo/anomalías , Feto
8.
J Neurosci ; 43(13): 2222-2241, 2023 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-36868853

RESUMEN

Selective serotonin reuptake inhibitors (SSRIs) are the most prescribed treatment for individuals experiencing major depressive disorder. The therapeutic mechanisms that take place before, during, or after SSRIs bind the serotonin transporter (SERT) are poorly understood, partially because no studies exist on the cellular and subcellular pharmacokinetic properties of SSRIs in living cells. We studied escitalopram and fluoxetine using new intensity-based, drug-sensing fluorescent reporters targeted to the plasma membrane, cytoplasm, or endoplasmic reticulum (ER) of cultured neurons and mammalian cell lines. We also used chemical detection of drug within cells and phospholipid membranes. The drugs attain equilibrium in neuronal cytoplasm and ER at approximately the same concentration as the externally applied solution, with time constants of a few s (escitalopram) or 200-300 s (fluoxetine). Simultaneously, the drugs accumulate within lipid membranes by ≥18-fold (escitalopram) or 180-fold (fluoxetine), and possibly by much larger factors. Both drugs leave cytoplasm, lumen, and membranes just as quickly during washout. We synthesized membrane-impermeant quaternary amine derivatives of the two SSRIs. The quaternary derivatives are substantially excluded from membrane, cytoplasm, and ER for >2.4 h. They inhibit SERT transport-associated currents sixfold or 11-fold less potently than the SSRIs (escitalopram or fluoxetine derivative, respectively), providing useful probes for distinguishing compartmentalized SSRI effects. Although our measurements are orders of magnitude faster than the therapeutic lag of SSRIs, these data suggest that SSRI-SERT interactions within organelles or membranes may play roles during either the therapeutic effects or the antidepressant discontinuation syndrome.SIGNIFICANCE STATEMENT Selective serotonin reuptake inhibitors stabilize mood in several disorders. In general, these drugs bind to SERT, which clears serotonin from CNS and peripheral tissues. SERT ligands are effective and relatively safe; primary care practitioners often prescribe them. However, they have several side effects and require 2-6 weeks of continuous administration until they act effectively. How they work remains perplexing, contrasting with earlier assumptions that the therapeutic mechanism involves SERT inhibition followed by increased extracellular serotonin levels. This study establishes that two SERT ligands, fluoxetine and escitalopram, enter neurons within minutes, while simultaneously accumulating in many membranes. Such knowledge will motivate future research, hopefully revealing where and how SERT ligands engage their therapeutic target(s).


Asunto(s)
Trastorno Depresivo Mayor , Inhibidores Selectivos de la Recaptación de Serotonina , Animales , Humanos , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Fluoxetina/farmacología , Escitalopram , Serotonina/metabolismo , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Retículo Endoplásmico/metabolismo , Citalopram/farmacología , Mamíferos
9.
Ann Oncol ; 35(7): 656-666, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38583574

RESUMEN

BACKGROUND: The optimal timing of radiotherapy (RT) after radical prostatectomy for prostate cancer has been uncertain. RADICALS-RT compared efficacy and safety of adjuvant RT versus an observation policy with salvage RT for prostate-specific antigen (PSA) failure. PATIENTS AND METHODS: RADICALS-RT was a randomised controlled trial enrolling patients with ≥1 risk factor (pT3/4, Gleason 7-10, positive margins, preoperative PSA≥10 ng/ml) for recurrence after radical prostatectomy. Patients were randomised 1:1 to adjuvant RT ('Adjuvant-RT') or an observation policy with salvage RT for PSA failure ('Salvage-RT') defined as PSA≥0.1 ng/ml or three consecutive rises. Stratification factors were Gleason score, margin status, planned RT schedule (52.5 Gy/20 fractions or 66 Gy/33 fractions) and treatment centre. The primary outcome measure was freedom-from-distant-metastasis (FFDM), designed with 80% power to detect an improvement from 90% with Salvage-RT (control) to 95% at 10 years with Adjuvant-RT. Secondary outcome measures were biochemical progression-free survival, freedom from non-protocol hormone therapy, safety and patient-reported outcomes. Standard survival analysis methods were used; hazard ratio (HR)<1 favours Adjuvant-RT. RESULTS: Between October 2007 and December 2016, 1396 participants from UK, Denmark, Canada and Ireland were randomised: 699 Salvage-RT, 697 Adjuvant-RT. Allocated groups were balanced with a median age of 65 years. Ninety-three percent (649/697) Adjuvant-RT reported RT within 6 months after randomisation; 39% (270/699) Salvage-RT reported RT during follow-up. Median follow-up was 7.8 years. With 80 distant metastasis events, 10-year FFDM was 93% for Adjuvant-RT and 90% for Salvage-RT: HR=0.68 [95% confidence interval (CI) 0.43-1.07, P=0.095]. Of 109 deaths, 17 were due to prostate cancer. Overall survival was not improved (HR=0.980, 95% CI 0.667-1.440, P=0.917). Adjuvant-RT reported worse urinary and faecal incontinence 1 year after randomisation (P=0.001); faecal incontinence remained significant after 10 years (P=0.017). CONCLUSION: Long-term results from RADICALS-RT confirm adjuvant RT after radical prostatectomy increases the risk of urinary and bowel morbidity, but does not meaningfully improve disease control. An observation policy with salvage RT for PSA failure should be the current standard after radical prostatectomy. TRIAL IDENTIFICATION: RADICALS, RADICALS-RT, ISRCTN40814031, NCT00541047.


Asunto(s)
Prostatectomía , Neoplasias de la Próstata , Terapia Recuperativa , Humanos , Masculino , Prostatectomía/métodos , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/patología , Anciano , Terapia Recuperativa/métodos , Persona de Mediana Edad , Radioterapia Adyuvante/efectos adversos , Radioterapia Adyuvante/métodos , Antígeno Prostático Específico/sangre , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/prevención & control , Clasificación del Tumor , Factores de Tiempo
10.
Ann Surg Oncol ; 31(2): 1049-1057, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37906385

RESUMEN

BACKGROUND: For some cancer operations, center volume is associated with improved patient outcomes. Whether this association is true for cytoreductive surgery/heated intraperitoneal chemotherapy (CRS/HIPEC) is unclear. Given the rapidly expanding use of CRS/HIPEC, the aim of this analysis was to determine whether a volume-outcome relationship exists for this strategy. METHODS: The Vizient Clinical Database® was queried for CRS/HIPEC cases from January 2020 through December 2022. Low-, medium-, and high-volume designations were made by sorting hospitals by case volume and creating equal tertiles based on total number of cases. Analysis was performed via one-way ANOVA with post-hoc Tukey test, as indicated. RESULTS: In the 36-month study period, 5165 cases were identified across 149 hospitals. Low- (n = 113), medium- (n = 25), and high-volume (n = 11) centers performed a median of 4, 21, and 47 cases per annum, respectively. Most cases were performed for appendiceal (39.3%) followed by gynecologic neoplasms (20.4%). Groups were similar with respect to age, gender, race, comorbidities, and histology. Low-volume centers were more likely to utilize the ICU post-operatively (59.6% vs. 40.5% vs. 36.3%; p = 0.02). No differences were observed in morbidity (9.4% vs. 7.1% vs. 9.0%, p = 0.71), mortality (0.9% vs. 0.6% vs. 0.7%, p = 0.93), length of stay (9.3 vs. 9.4 vs. 10 days, p = 0.83), 30-day readmissions (5.6% vs. 5.6% vs. 5.6%, p = 1.0), or total cost among groups. CONCLUSIONS: No association was found between CRS/HIPEC hospital volume and post-operative outcomes. These data suggest that in academic medical centers with HIPEC programs, outcomes for commonly treated cancers are not associated with hospital volume.


Asunto(s)
Neoplasias del Apéndice , Hipertermia Inducida , Neoplasias Peritoneales , Humanos , Femenino , Neoplasias Peritoneales/patología , Estudios Retrospectivos , Quimioterapia Intraperitoneal Hipertérmica , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Hospitales , Procedimientos Quirúrgicos de Citorreducción/efectos adversos , Neoplasias del Apéndice/patología , Terapia Combinada , Tasa de Supervivencia
11.
Ann Surg Oncol ; 31(7): 4203-4212, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38594579

RESUMEN

BACKGROUND: Mucinous appendiceal adenocarcinomas (MAA) and non-mucinous appendiceal adenocarcinomas (NMAA) demonstrate differences in rates and patterns of recurrence, which may inform the appropriate extent of surgical resection (i.e., appendectomy versus colectomy). The impact of extent of resection on disease-specific survival (DSS) for each histologic subtype was assessed. PATIENTS AND METHODS: Patients with resected, non-metastatic MAA and NMAA were identified in the Surveillance, Epidemiology, and End Results database (2000-2020). Multivariable models were created to examine predictors of colectomy for each histologic subtype. DSS was calculated using Kaplan-Meier estimates and examined using Cox proportional hazards modeling. RESULTS: Among 4674 patients (MAA: n = 1990, 42.6%; NMAA: n = 2684, 57.4%), the majority (67.8%) underwent colectomy. Among colectomy patients, the rate of nodal positivity increased with higher T-stage (MAA: T1: 4.6%, T2: 4.0%, T3: 17.1%, T4: 21.6%, p < 0.001; NMAA: T1: 6.8%, T2: 11.4%, T3: 25.6%, T4: 43.8%, p < 0.001) and higher tumor grade (MAA: well differentiated: 7.7%, moderately differentiated: 19.2%, and poorly differentiated: 31.3%; NMAA: well differentiated: 9.0%, moderately differentiated: 20.5%, and 44.4%; p < 0.001). Nodal positivity was more frequently observed in NMAA (27.6% versus 16.4%, p < 0.001). Utilization of colectomy was associated with improved DSS for NMAA patients with T2 (log rank p = 0.095) and T3 (log rank p = 0.018) tumors as well as moderately differentiated histology (log rank p = 0.006). Utilization of colectomy was not associated with improved DSS for MAA patients, which was confirmed in a multivariable model for T-stage, grade, and use of adjuvant chemotherapy [hazard ratio (HR) 1.00, 95% confidence interval (CI) 0.81-1.22]. CONCLUSIONS: Colectomy was associated with improved DSS for patients with NMAA but not MAA. Colectomy for MAA may not be required.


Asunto(s)
Adenocarcinoma Mucinoso , Adenocarcinoma , Apendicectomía , Neoplasias del Apéndice , Colectomía , Programa de VERF , Humanos , Neoplasias del Apéndice/patología , Neoplasias del Apéndice/cirugía , Neoplasias del Apéndice/mortalidad , Femenino , Masculino , Adenocarcinoma Mucinoso/cirugía , Adenocarcinoma Mucinoso/patología , Adenocarcinoma Mucinoso/mortalidad , Persona de Mediana Edad , Anciano , Tasa de Supervivencia , Adenocarcinoma/cirugía , Adenocarcinoma/patología , Adenocarcinoma/mortalidad , Estudios de Seguimiento , Pronóstico , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Adulto
12.
Psychol Med ; 54(5): 1034-1044, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37753626

RESUMEN

BACKGROUND: Social cognition impairments are a common feature of alcohol use disorders (AUD). However, it remains unclear whether these impairments are solely the consequence of chronic alcohol consumption or whether they could be a marker of vulnerability. METHODS: The present study implemented a family history approach to address this question for a key process of social cognition: theory of mind (ToM). Thirty healthy adults with a family history of AUD (FH+) and 30 healthy adults with a negative family history of AUD (FH-), matched for age, sex, and education level, underwent an fMRI cartoon-vignette paradigm assessing cognitive and affective ToM. Participants also completed questionnaires evaluating anxiety, depressive symptoms, childhood trauma, and alexithymia. RESULTS: Results indicated that FH+ individuals differed from FH- individuals on affective but not cognitive ToM processing, at both the behavioral and neural levels. At the behavioral level, the FH+ group had lower response accuracy for affective ToM compared with the FH- group. At the neural level, the FH+ group had higher brain activations in the left insula and inferior frontal cortex during affective ToM processing. These activations remained significant when controlling for depressive symptoms, anxiety, and childhood trauma. CONCLUSIONS: These findings highlight difficulties during affective ToM processing among first-degree relatives of AUD patients, supporting the idea that some of the impairments exhibited by these patients may already be present before the onset of AUD and may be considered a marker of vulnerability.


Asunto(s)
Alcoholismo , Teoría de la Mente , Adulto , Humanos , Teoría de la Mente/fisiología , Alcoholismo/diagnóstico por imagen , Afecto/fisiología , Consumo de Bebidas Alcohólicas , Cognición/fisiología
13.
Soft Matter ; 20(11): 2474-2479, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38384251

RESUMEN

Motivated by recent experiments studying the creep and breakup of a protein gel under stress, we introduce a simple mesoscopic model for the irreversible failure of gels and fibrous materials, and demonstrate it to capture much of the phenomenology seen experimentally. This includes a primary creep regime in which the shear rate decreases as a power law over several decades of time, a secondary crossover regime in which the shear rate attains a minimum, and a tertiary regime in which the shear rate increases dramatically up to a finite time singularity, signifying irreversible material failure. The model also captures a linear Monkman-Grant scaling of the failure time with the earlier time at which the shear rate attained its minimum, and a Basquin-like power law scaling of the failure time with imposed stress, as seen experimentally. The model furthermore predicts a slow accumulation of low levels of material damage during primary creep, followed by the growth of fractures leading to sudden material failure, as seen experimentally.

14.
J Surg Oncol ; 129(4): 745-753, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38225867

RESUMEN

INTRODUCTION: The International Study Group of Liver Surgery's criteria stratifies post-hepatectomy liver failure (PHLF) into grades A, B, and C. The clinical significance of these grades has not been fully established. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) hepatectomy-targeted database was analyzed. Outcomes between patients without PHLF, with grade A PHLF, and grade B or C PHLF were compared. Univariate and multivariable logistic regression were performed. RESULTS: Six thousand two hundred seventy-four adults undergoing elective major hepatectomy were included in the analysis. The incidence of grade A PHLF was 4.3% and grade B or C was 5.3%. Mortality was similar between patients without PHLF (1.2%) and with grade A PHLF (1.1%), but higher in those with grades B or C PHLF (25.4%). Overall morbidities rates were 19.3%, 41.7%, and 72.8% in patients without PHLF, with grade A PHLF, and with grade B or C PHLF, respectively (p < 0.001). Grade A PHLF was associated with increased morbidity (grade A: odds ratios [OR] 2.7 [95% CI: 2.0-3.5]), unplanned reoperation (grade A: OR 3.4 [95% CI: 2.2-5.1]), nonoperative intervention (grade A: OR 2.6 [95% CI: 1.9-3.6]), length of stay (grade A: OR 3.1 [95% CI: 2.3-4.1]), and readmission (grade A: OR 1.8 [95% CI: 1.3-2.5]) compared to patients without PHLF. CONCLUSIONS: Although mortality was similar between patients without PHLF and with grade A PHLF, other postoperative outcomes were notably inferior. Grade A PHLF is a clinically distinct entity with relevant associated postoperative morbidity.


Asunto(s)
Carcinoma Hepatocelular , Fallo Hepático , Neoplasias Hepáticas , Adulto , Humanos , Hepatectomía/efectos adversos , Relevancia Clínica , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/complicaciones , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Fallo Hepático/epidemiología , Fallo Hepático/etiología , Estudios Retrospectivos , Carcinoma Hepatocelular/cirugía
15.
Nature ; 562(7727): 406-409, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30333580

RESUMEN

The efficiency of generating electricity from heat using concentrated solar power plants (which use mirrors or lenses to concentrate sunlight in order to drive heat engines, usually involving turbines) may be appreciably increased by operating with higher turbine inlet temperatures, but this would require improved heat exchanger materials. By operating turbines with inlet temperatures above 1,023 kelvin using closed-cycle high-pressure supercritical carbon dioxide (sCO2) recompression cycles, instead of using conventional (such as subcritical steam Rankine) cycles with inlet temperatures below 823 kelvin1-3, the relative heat-to-electricity conversion efficiency may be increased by more than 20 per cent. The resulting reduction in the cost of dispatchable electricity from concentrated solar power plants (coupled with thermal energy storage4-6) would be an important step towards direct competition with fossil-fuel-based plants and a large reduction in greenhouse gas emissions7. However, the inlet temperatures of closed-cycle high-pressure sCO2 turbine systems are limited8 by the thermomechanical performance of the compact, metal-alloy-based, printed-circuit-type heat exchangers used to transfer heat to sCO2. Here we present a robust composite of ceramic (zirconium carbide, ZrC) and the refractory metal tungsten (W) for use in printed-circuit-type heat exchangers at temperatures above 1,023 kelvin9. This composite has attractive high-temperature thermal, mechanical and chemical properties and can be processed in a cost-effective manner. We fabricated ZrC/W-based heat exchanger plates with tunable channel patterns by the shape-and-size-preserving chemical conversion of porous tungsten carbide plates. The dense ZrC/W-based composites exhibited failure strengths of over 350 megapascals at 1,073 kelvin, and thermal conductivity values two to three times greater than those of iron- or nickel-based alloys at this temperature. Corrosion resistance to sCO2 at 1,023 kelvin and 20 megapascals was achieved10 by bonding a copper layer to the composite surface and adding 50 parts per million carbon monoxide to sCO2. Techno-economic analyses indicate that ZrC/W-based heat exchangers can strongly outperform nickel-superalloy-based printed-circuit heat exchangers at lower cost.

16.
Cereb Cortex ; 33(4): 1130-1139, 2023 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-35349640

RESUMEN

Mild isolated fetal ventriculomegaly (iFVM) is the most common abnormality of the fetal central nervous system. It is characterized by enlargement of one or both of the lateral ventricles (defined as ventricular width greater than 10 mm, but less than 12 mm). Despite its high prevalence, the pathophysiology of iFVM during fetal brain development and the neurobiological substrate beyond ventricular enlargement remain unexplored. In this work, we aimed to establish the relationships between the structural development of transient fetal brain zones/compartments and increased cerebrospinal fluid volume. For this purpose, we used in vivo structural T2-weighted magnetic resonance imaging of 89 fetuses (48 controls and 41 cases with iFVM). Our results indicate abnormal development of transient zones/compartments belonging to both hemispheres (i.e. on the side with and also on the contralateral side without a dilated ventricle) in fetuses with iFVM. Specifically, compared to controls, we observed enlargement of proliferative zones and overgrowth of the cortical plate in iFVM with associated reduction of volumes of central structures, subplate, and fetal white matter. These results indicate that enlarged lateral ventricles might be linked to the development of transient fetal zones and that global brain development should be taken into consideration when evaluating iFVM.


Asunto(s)
Hidrocefalia , Imagen por Resonancia Magnética , Embarazo , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Ultrasonografía Prenatal/métodos , Hidrocefalia/diagnóstico por imagen , Hidrocefalia/complicaciones , Hidrocefalia/patología , Encéfalo/patología , Feto
17.
Cereb Cortex ; 33(21): 10793-10801, 2023 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-37697904

RESUMEN

Non-syndromic, isolated musculoskeletal birth defects (niMSBDs) are among the leading causes of pediatric hospitalization. However, little is known about brain development in niMSBDs. Our study aimed to characterize prenatal brain development in fetuses with niMSBDs and identify altered brain regions compared to controls. We retrospectively analyzed in vivo structural T2-weighted MRIs of 99 fetuses (48 controls and 51 niMSBDs cases). For each group (19-31 and >31 gestational weeks (GW)), we conducted repeated-measures regression analysis with relative regional volume (% brain hemisphere) as a dependent variable (adjusted for age, side, and interactions). Between 19 and 31GW, fetuses with niMSBDs had a significantly (P < 0.001) smaller relative volume of the intermediate zone (-22.9 ± 3.2%) and cerebellum (-16.1 ± 3.5%,) and a larger relative volume of proliferative zones (38.3 ± 7.2%), the ganglionic eminence (34.8 ± 7.3%), and the ventricles (35.8 ± 8.0%). Between 32 and 37 GW, compared to the controls, niMSBDs showed significantly smaller volumes of central regions (-9.1 ± 2.1%) and larger volumes of the cortical plate. Our results suggest there is altered brain development in fetuses with niMSBDs compared to controls (13.1 ± 4.2%). Further basic and translational neuroscience research is needed to better visualize these differences and to characterize the altered development in fetuses with specific niMSBDs.


Asunto(s)
Encéfalo , Cerebro , Embarazo , Femenino , Humanos , Niño , Estudios Retrospectivos , Feto , Desarrollo Fetal , Imagen por Resonancia Magnética/métodos , Edad Gestacional
18.
Environ Res ; 255: 119071, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38751005

RESUMEN

BACKGROUND: Exposure to polychlorinated biphenyls (PCBs) has been linked to risk factors for cardiovascular disease such as increased inflammation, accelerated atherosclerosis, diabetes, and sex hormone dysregulation. Furthermore, there is increasing evidence suggesting associations between internal dose of PCBs and cardiovascular outcomes. OBJECTIVES: The purpose of this study is to investigate longitudinal associations of PCBs with coronary heart disease (CHD)-related outcomes in a cohort of Great Lakes sport fish consumers. METHODS: The Great Lakes Sport Fish Consumer cohort was established in the early 1990's. Eight hundred nineteen participants were followed from 1993 to 2017. Serum PCBs were measured in 1994/1995 (baseline), in 2001, and in 2004, while health history questionnaires were administered in 1996, 2003, 2010, and 2017. Cox models were used to prospectively investigate associations of total PCBs and PCB groupings, based on aryl hydrocarbon receptor activity, with incident self-reported physician diagnosis of coronary heart disease (CHD), myocardial infarction (MI), and angina pectoris. RESULTS: A 2-fold increase in phenobarbital-type PCBs was associated with a 72% increase in likelihood of self-reported incident diagnosis of CHD (HR=1.72, 95% CI: 1.06-2.81; p=0.0294). Similar results were observed for total PCBs (HR=1.68, 95% CI: 1.05-2.69; p=0.0306) and mixed methacholine/phenobarbital type (mixed-type) PCBs (HR=1.60, 95% CI: 1.02-2.52; p=0.0427), but not methacholine-type PCBs. PCBs were not strongly associated with risk of MI or angina. CONCLUSIONS: This study presents evidence that exposure to PCBs increases the risk of developing coronary heart disease. Given the large number of risk factors and causal pathways for CHD, future research is required to better understand biological mechanisms of action for PCBs on CHD.


Asunto(s)
Enfermedad Coronaria , Bifenilos Policlorados , Contaminantes Químicos del Agua , Bifenilos Policlorados/sangre , Bifenilos Policlorados/efectos adversos , Humanos , Masculino , Femenino , Persona de Mediana Edad , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/inducido químicamente , Adulto , Contaminantes Químicos del Agua/efectos adversos , Contaminantes Químicos del Agua/sangre , Contaminantes Químicos del Agua/análisis , Peces , Great Lakes Region , Anciano , Animales , Incidencia , Contaminación de Alimentos/análisis
19.
Dev Psychopathol ; : 1-12, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38477321

RESUMEN

Black and Latinx caregivers face high risk for parenting stress and racism-related stress due to experiences of racial discrimination (RD). This study aimed to explore the associations between RD, parenting stress, and psychological distress in caregiver-child dyads, as well as the impact of a mentalizing-focused group intervention on caregivers' experiences of RD distress. Ethnoracially minoritized caregivers of children aged 5-17 years old participated in a non-randomized clinical trial (N = 70). They received either a 12-session mentalizing-focused group parenting intervention or treatment-as-usual in outpatient psychiatry. We assessed self-reported frequency and distress related to RD, parenting stress, and psychological distress at baseline (T1) and post-intervention (T2). Caregiver- and self-reported child psychological distress were also measured. The results showed that greater RD frequency and greater RD distress separately predicted higher overall parenting stress and parental role-related distress. Greater RD distress was linked to increased psychological distress in caregivers. Similarly, greater RD frequency and distress among caregivers were associated with higher caregiver-reported, but not self-reported, child psychological distress. No significant changes in RD distress were observed between T1 and T2 for either of the treatment groups. These findings highlight the exacerbating role of RD on parenting stress and psychological distress among ethnoracially minoritized caregivers and their children.

20.
Sleep Breath ; 28(3): 1173-1185, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38225441

RESUMEN

PURPOSE: Previous studies assessed different components of telemedicine management pathway for OSA instead of the whole pathway. This randomized, controlled, and non-inferiority trial aimed to assess whether telemedicine management is clinically inferior to in-person care in China. METHODS: Adults suspected of OSA were randomized to telemedicine (web-based questionnaires, self-administered home sleep apnea test [HSAT], automatically adjusting positive airway pressure [APAP], and video-conference visits) or in-person management (paper questionnaires, in-person HSAT set-up, APAP, and face-to-face visits). Participants with an apnea-hypopnea index (AHI) ≥ 15 events/hour received APAP for 3 months. The non-inferiority analysis was based on the change in Functional Outcomes of Sleep Questionnaire (FOSQ) score and APAP adherence. Cost-effectiveness analysis was performed. RESULTS: In the modified intent-to-treat analysis set (n = 111 telemedicine, 111 in-person), FOSQ scores improved 1.73 (95% confidence interval [CI], 1.31-2.14) points with telemedicine and 2.05 (1.64-2.46) points with in-person care. The lower bound of the one-sided 95% non-inferiority CI for the difference in change between groups of - 0.812 was larger than the non-inferiority threshold of - 1. APAP adherence at 3 months was 243.3 (223.1-263.5) minutes/night for telemedicine and 241.6 (221.3-261.8) minutes/night for in-person care. The lower bound of the one-sided 95% non-inferiority CI of - 22.2 min/night was higher than the non-inferiority delta of - 45 min/night. Telemedicine had lower total costs than in-person management (CNY 1482.7 ± 377.2 vs. 1912.6 ± 681.3; p < 0.0001), driven by patient costs, but no significant difference in QALYs. CONCLUSIONS: Functional outcomes and adherence were not clinically inferior in patients managed by a comprehensive telemedicine approach compared to those receiving in-person care in China. CLINICAL TRIAL REGISTRATION: https://www.chictr.org.cn , Registration number ChiCTR2000030546. Retrospectively registered on March 06, 2020.


Asunto(s)
Apnea Obstructiva del Sueño , Telemedicina , Humanos , Apnea Obstructiva del Sueño/terapia , Apnea Obstructiva del Sueño/economía , Masculino , China , Femenino , Persona de Mediana Edad , Adulto , Presión de las Vías Aéreas Positiva Contínua , Anciano , Análisis Costo-Beneficio
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