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1.
J Vis ; 24(6): 9, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38856981

RESUMEN

Four experiments were conducted to gain a better understanding of the visual mechanisms related to how integration of partial shape cues provides for recognition of the full shape. In each experiment, letters formed as outline contours were displayed as a sequence of adjacent segments (fragments), each visible during a 17-ms time frame. The first experiment varied the contrast of the fragments. There were substantial individual differences in contrast sensitivity, so stimulus displays in the masking experiments that followed were calibrated to the sensitivity of each participant. Masks were displayed either as patterns that filled the entire screen (full field) or as successive strips that were sliced from the pattern, each strip lying across the location of the letter fragment that had been shown a moment before. Contrast of masks were varied to be lighter or darker than the letter fragments. Full-field masks, whether light or dark, provided relatively little impairment of recognition, as was the case for mask strips that were lighter than the letter fragments. However, dark strip masks proved to be very effective, with the degree of recognition impairment becoming larger as mask contrast was increased. A final experiment found the strip masks to be most effective when they overlapped the location where the letter fragments had been shown a moment before. They became progressively less effective with increased spatial separation from that location. Results are discussed with extensive reference to potential brain mechanisms for integrating shape cues.


Asunto(s)
Sensibilidad de Contraste , Percepción de Forma , Reconocimiento Visual de Modelos , Enmascaramiento Perceptual , Estimulación Luminosa , Humanos , Enmascaramiento Perceptual/fisiología , Sensibilidad de Contraste/fisiología , Estimulación Luminosa/métodos , Adulto , Reconocimiento Visual de Modelos/fisiología , Percepción de Forma/fisiología , Masculino , Femenino , Señales (Psicología) , Adulto Joven
2.
Immunol Invest ; : 1-13, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847319

RESUMEN

First described in 2020, multi-system inflammatory syndrome in children (MIS-C) is an, initially life-threatening, disease characterised by severe inflammation and following exposure to SARS-CoV-2. The immunopathology of MIS-C involves a hyperinflammation characterised by a cytokine storm and activation of both the innate and adaptive immune system, eventually leading to multi-organ failure. Several etiological theories are described in literature. Firstly, it is suggested that the gut plays an important role in the translocation of microbial products to the systemic circulation. Additionally, the production of autoantibodies that develop after the initial infection with SARS-CoV-2 might lead to many of its broad clinical symptoms. Finally, the superantigen theory where non-specific binding of the SARS-CoV-2 spike glycoprotein to the T-cell receptor leads to a subsequent activation of T cells, generating a powerful immune response. Despite the sudden outbreak of MIS-C and alarming messages, as of 2024, cases have declined drastically and subsequently show a less severe clinical spectrum. However, subacute cases not meeting current diagnostic criteria might be overlooked even though they represent a valuable research population. In the future, research should focus on adjusting these criteria to better understand the broad pathophysiology of MIS-C, aiding early detection, therapy, and prediction.

3.
Sci Rep ; 14(1): 5575, 2024 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448481

RESUMEN

Wastewater surveillance has proven a cost-effective key public health tool to understand a wide range of community health diseases and has been a strong source of information on community levels and spread for health departments throughout the SARS- CoV-2 pandemic. Studies spanning the globe demonstrate the strong association between virus levels observed in wastewater and quality clinical case information of the population served by the sewershed. Few of these studies incorporate the temporal dependence present in sampling over time, which can lead to estimation issues which in turn impact conclusions. We contribute to the literature for this important public health science by putting forward time series methods coupled with statistical process control that (1) capture the evolving trend of a disease in the population; (2) separate the uncertainty in the population disease trend from the uncertainty due to sampling and measurement; and (3) support comparison of sub-sewershed population disease dynamics with those of the population represented by the larger downstream treatment plant. Our statistical methods incorporate the fact that measurements are over time, ensuring correct statistical conclusions. We provide a retrospective example of how sub-sewersheds virus levels compare to the upstream wastewater treatment plant virus levels. An on-line algorithm supports real-time statistical assessment of deviations of virus level in a population represented by a sub-sewershed to the virus level in the corresponding larger downstream wastewater treatment plant. This information supports public health decisions by spotlighting segments of the population where outbreaks may be occurring.


Asunto(s)
COVID-19 , Aguas Residuales , Humanos , Factores de Tiempo , ARN Viral/genética , SARS-CoV-2/genética , Estudios Retrospectivos , COVID-19/epidemiología , Monitoreo Epidemiológico Basado en Aguas Residuales
4.
Chaos ; 34(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38166172

RESUMEN

Nonlinear dynamical systems, such as climate systems, often switch from one metastable state to another when subject to noise. The first occurrence of such state transition, which is usually characterized by the first passage time, has gained enormous interest in many engineering and scientific fields. We develop an efficient numerical method to compute the probability density of the first passage time for state transitions in stochastic dynamical systems driven by Brownian motions. The proposed method involves solving a singular integral equation, which determines probability density of the first passage time. Some numerical examples, with application to a simplified thermohaline circulation system, are provided to illustrate and verify the proposed method.

5.
ACS Macro Lett ; 12(5): 605-611, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37071887

RESUMEN

A method for the acyclic diene metathesis polymerization of semiaromatic amides is described. The procedure uses second-generation Grubbs' catalyst and N-cyclohexyl-2-pyrrolidone (CHP), a high boiling, polar solvent capable of solubilizing both monomer and polymer. The addition of methanol to the reaction was found to significantly increase polymer molar mass although the role of the alcohol is currently not understood. Hydrogenation with hydrogen gas and Wilkinson's catalyst resulted in near-quantitative saturation. All polymers synthesized here exhibit a hierarchical semicrystalline morphology driven by ordering of aromatic amide groups via strong nonbonded interactions. Furthermore, the melting points can be tuned over a >100 °C range by precise substitution at just one of the backbone positions on each mer (<5% of the total).

6.
JTO Clin Res Rep ; 4(4): 100498, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37020927

RESUMEN

Introduction: CD47 is a tumor antigen that inhibits phagocytosis leading to immune evasion. Anti-CD47 therapy is a promising new immunotherapy across numerous tumor types, but it has not been tested in thymic epithelial tumors (TETs): thymomas and thymic carcinomas. TETs are rare tumors that are difficult to treat, especially with programmed cell death protein 1/programmed death-ligand 1 checkpoint inhibitors, owing to the excessive rates of immune-related adverse events. This study investigated the levels of CD47 expression in TETs to explore the possibility of anti-CD47 therapy. Methods: A total of 67 thymic tumors (63 thymomas and 4 thymic carcinomas) and 14 benign thymus controls and their clinical data were included. Samples were stained for CD47 expression (rabbit monoclonal antibody SP279, Abcam, Waltham, MA) and scored for both intensity and H-score (intensity multiplied by the percentage of tumor involved). Intensity was defined as follows: 0 = none, 1 = weak, 2 = moderate, and 3 = strong. H-scores ranged from 0 to 300. Samples with an intensity score below 2 or an H-score below 150 were considered CD47low, whereas the rest were CD47high. Results: Compared with normal thymic tissues, TETs were more frequently CD47 positive and had significantly higher levels of CD47 expression. CD47 was positive in 79.1% of TETs compared with 57.1% of normal thymus. The level of CD47 expression was 16-fold higher in TETs (mean H-score 75.0 versus 4.6, p = 0.003). Multivariate analysis adjusted for age, sex, stage, resection status, and performance status revealed that CD47-high tumors were highly correlated with WHO histology type (p = 0.028). The most frequent CD47high tumors, in contrast to CD47low tumors, were types A (28.6% versus 7.5%) and AB (57.1% versus 13.2%), and the least frequent were B1 (7.1% versus 24.5%), B2 (0% versus 35.8%), B3 (7.1% versus 11.3%), and C (0% versus 7.5%). Conclusions: In contrast to normal thymus, TETs had significantly higher levels of CD47 expression. Tumor samples with high CD47 expression were mostly WHO types A and AB. This is the first study to explore CD47 expression in thymic cancers and lends support for ongoing investigation of anti-CD47 macrophage checkpoint inhibitor therapy in these tumors.

7.
Water Res ; 231: 119648, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36702023

RESUMEN

Wastewater surveillance is a passive and efficient way to monitor the spread of infectious diseases in large populations and high transmission areas such as preK-12 schools. Infections caused by respiratory viruses in school-aged children are likely underreported, particularly because many children may be asymptomatic or mildly symptomatic. Wastewater monitoring of SARS-CoV-2 has been studied extensively and primarily by sampling at centralized wastewater treatment plants, and there are limited studies on SARS-CoV-2 in preK-12 school wastewater. Similarly, wastewater detections of influenza have only been reported in wastewater treatment plant and university manhole samples. Here, we present the results of a 17-month wastewater monitoring program for SARS-CoV-2 (n = 2176 samples) and influenza A and B (n = 1217 samples) in 51 preK-12 schools. We show that school wastewater concentrations of SARS-CoV-2 RNA were strongly associated with COVID-19 cases in schools and community positivity rates, and that influenza detections in school wastewater were significantly associated with citywide influenza diagnosis rates. Results were communicated back to schools and local communities to enable mitigation strategies to stop the spread, and direct resources such as testing and vaccination clinics. This study demonstrates that school wastewater surveillance is reflective of local infections at several population levels and plays a crucial role in the detection and mitigation of outbreaks.


Asunto(s)
COVID-19 , Gripe Humana , Niño , Humanos , Gripe Humana/epidemiología , SARS-CoV-2 , Aguas Residuales , COVID-19/epidemiología , ARN Viral , Monitoreo Epidemiológico Basado en Aguas Residuales
8.
Endocr Relat Cancer ; 29(12): 665-679, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36165930

RESUMEN

High-grade (grade 3) neuroendocrine neoplasms (G3 NENs) have poor survival outcomes. From a clinical standpoint, G3 NENs are usually grouped regardless of primary site and treated similarly. Little is known regarding the underlying genomics of these rare tumors, especially when compared across different primary sites. We performed whole transcriptome (n = 46), whole exome (n = 40), and gene copy number (n = 43) sequencing on G3 NEN formalin-fixed, paraffin-embedded samples from diverse organs (in total, 17 were lung, 16 were gastroenteropancreatic, and 13 other). G3 NENs despite arising from diverse primary sites did not have gene expression profiles that were easily segregated by organ of origin. Across all G3 NENs, TP53, APC, RB1, and CDKN2A were significantly mutated. The CDK4/6 cell cycling pathway was mutated in 95% of cases, with upregulation of oncogenes within this pathway. G3 NENs had high tumor mutation burden (mean 7.09 mutations/MB), with 20% having >10 mutations/MB. Two somatic copy number alterations were significantly associated with worse prognosis across tissue types: focal deletion 22q13.31 (HR, 7.82; P = 0.034) and arm amplification 19q (HR, 4.82; P = 0.032). This study is among the most diverse genomic study of high-grade neuroendocrine neoplasms. We uncovered genomic features previously unrecognized for this rapidly fatal and rare cancer type that could have potential prognostic and therapeutic implications.


Asunto(s)
Neoplasias Intestinales , Tumores Neuroendocrinos , Neoplasias Pancreáticas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patología , Tumores Neuroendocrinos/patología , Pronóstico , Genómica , Mutación , Neoplasias Pancreáticas/patología , Neoplasias Intestinales/patología
9.
Am J Case Rep ; 23: e936288, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35927927

RESUMEN

BACKGROUND Primary retroperitoneal choriocarcinoma is a rare form of extragonadal germ cell tumor that is highly aggressive and responds poorly to chemoradiation. Extragonadal choriocarcinomas are notoriously challenging to diagnose, and have often progressed to advanced disease by the time of diagnosis. The survival rate for extragonadal choriocarcinoma is approximately 30%, which is much lower than that of extragonadal non-seminomatous germ cell tumors (GCT) in general. CASE REPORT A 24-year-old man with no significant past medical history presented with left-sided, pleuritic chest pain and back pain radiating down his left leg, of 1-year duration. Computed tomography (CT) of the chest revealed multiple bilateral pulmonary nodules and a CT of the abdomen and pelvis showed a large heterogeneous soft tissue mass measuring 9.3×8×10.5 cm. A CT-guided core needle biopsy of a lung nodule was performed and the findings were consistent with the diagnosis of metastatic choriocarcinoma. Magnetic resonance imaging (MRI) of the brain was negative for metastatic disease. Tumor markers were significant for a markedly elevated beta human chorionic gonadotropin (B-hCG) of 104 712 mIU/mL. He was diagnosed with a stage IIIC germ cell tumor, further classified as a primary retroperitoneal choriocarcinoma with lung metastasis, and was started on urgent inpatient chemotherapy. CONCLUSIONS Due to the poor outcomes associated with extragonadal choriocarcinoma, it is important to promptly and correctly identify this malignancy in order to initiate treatment in a timely manner. The following case report explores the histopathologic characterization of this malignancy and describes the clinical course and outcomes from treatment for this patient.


Asunto(s)
Coriocarcinoma , Neoplasias Pulmonares , Neoplasias de Células Germinales y Embrionarias , Neoplasias Retroperitoneales , Neoplasias Testiculares , Adulto , Coriocarcinoma/diagnóstico , Coriocarcinoma/patología , Femenino , Humanos , Neoplasias Pulmonares/secundario , Masculino , Neoplasias de Células Germinales y Embrionarias/complicaciones , Neoplasias Retroperitoneales/patología , Neoplasias Testiculares/patología , Adulto Joven
10.
Curr Oncol Rep ; 24(7): 819-824, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35305210

RESUMEN

PURPOSE OF REVIEW: Lung neuroendocrine tumors (NETs)-typical carcinoids and atypical carcinoids-have unique molecular alterations that are distinct from neuroendocrine carcinomas of the lung and non-small cell lung cancers. Here, we review the role of molecular profiling in the prognosis and treatment of lung NETs. RECENT FINDINGS: There have been no recently identified molecular prognostic factors for lung NETs and none that have been routinely used to guide management of patients with lung NETs. Previous findings suggest that patients with loss of chromosome 11q may have a worse prognosis along with upregulation of anti-apoptotic pathways (e.g., loss of CD44 and OTP protein expression). Lung NETs rarely harbor driver mutations commonly found in non-small cell lung cancer (NSCLC) or TP53/RB1 mutations found universally in small cell lung cancer. Lung NETs also have low tumor mutation burden and low PD-L1 expression. Everolimus, an mTOR inhibitor and the only FDA approved therapy for unresectable lung NETs, is an effective treatment but the presence of a molecular alteration in the PI3K/AKT/mTOR pathway is not known to predict treatment response. The predominant mutations in lung NETs occur in genes regulating chromatin remodeling and histone modification, with potential targeted therapies emerging in clinical trials. Lung NETs have recurring alterations in genes that regulate the epigenome. Future targeted therapy interfering with epigenetic pathways may hold promise.


Asunto(s)
Antineoplásicos , Tumor Carcinoide , Carcinoma Neuroendocrino , Carcinoma de Pulmón de Células no Pequeñas , Everolimus , Neoplasias Pulmonares , Tumores Neuroendocrinos , Antineoplásicos/uso terapéutico , Tumor Carcinoide/tratamiento farmacológico , Tumor Carcinoide/genética , Carcinoma Neuroendocrino/tratamiento farmacológico , Carcinoma Neuroendocrino/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Everolimus/uso terapéutico , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Recurrencia Local de Neoplasia/metabolismo , Tumores Neuroendocrinos/tratamiento farmacológico , Tumores Neuroendocrinos/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Serina-Treonina Quinasas TOR/antagonistas & inhibidores
14.
Cureus ; 13(3): e13695, 2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33833916

RESUMEN

Spontaneous pneumomediastinum is a rare condition characterized by interstitial air within the mediastinum without any obvious causative factors. It is most commonly found in young men, and the clinical presentation is typically associated with chest or neck pain and dyspnea. Objective findings can include subcutaneous emphysema of the neck and chest. Asymptomatic cases are exceedingly rare. In this report, we present the case of a 20-year-old woman who presented with acute psychosis and the incidental imaging finding of pneumomediastinum without any associated clinical signs or symptoms.

15.
Clin Cancer Res ; 26(18): 4785-4794, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32591465

RESUMEN

PURPOSE: Taletrectinib (DS-6051b/AB-106) is an oral, tyrosine kinase inhibitor of ROS1 and NTRK with potent preclinical activity against ROS1 G2032R solvent-front mutation among others. We report the first-in-human U.S. phase I results of taletrectinib. PATIENTS AND METHODS: Patients ≥18 years old with neuroendocrine tumors, with tumor-induced pain, or tumors harboring ROS1/NTRK rearrangements were eligible. Accelerated titration followed by modified continuous reassessment method and escalation with overdose control was used (50-1,200 mg once daily or 400 mg twice daily). Primary objectives were safety/tolerability, and MTD determination. Secondary objectives were food-effect pharmacokinetics and antitumor activity. RESULTS: A total of 46 patients were enrolled. Steady-state peak concentration (C max) and exposure (AUC0-8) increased dose dependently from 50-mg to 800-mg once-daily doses. The ratio of the geometric mean of AUC0-24 between low-fat-diet-fed/fasted state was 123% (90% confidence interval, 104%-149%). Dose-limiting toxicities (grade 3 transaminases increase) occurred in two patients (1,200-mg once-daily dose). MTD was 800 mg once daily. Most common treatment-related adverse events were nausea (47.8%), diarrhea (43.5%), and vomiting (32.6%). Pain score reductions were observed in the 800-mg once-daily dose cohort. Confirmed objective response rate was 33.3% among the six patients with RECIST-evaluable crizotinib-refractory ROS1+ NSCLC. One patient with TPM3-NTRK1 differentiated thyroid cancer achieving a confirmed partial response of 27 months at data cutoff. We identified a cabozantinib-sensitive ROS1 L2086F as an acquired taletrectinib-resistance mutation. CONCLUSIONS: Taletrectinib has manageable toxicities at the MTD of 800 mg daily. Preliminary efficacy was observed in patients with crizotinib-refractory ROS1+ NSCLC.


Asunto(s)
Interacciones Alimento-Droga , Imidazoles/efectos adversos , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/efectos adversos , Piridazinas/efectos adversos , Adulto , Anciano , Femenino , Humanos , Imidazoles/administración & dosificación , Imidazoles/farmacocinética , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias/diagnóstico , Neoplasias/patología , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacocinética , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Piridazinas/administración & dosificación , Piridazinas/farmacocinética , Receptor trkA/antagonistas & inhibidores , Criterios de Evaluación de Respuesta en Tumores Sólidos , Adulto Joven
18.
Dev Cell ; 48(1): 17-31.e6, 2019 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-30595533

RESUMEN

Delineating molecular and cellular events that precede appendage morphogenesis has been challenging due to the inability to distinguish quantitative molecular differences between cells that lack histological distinction. The hair follicle (HF) dermal condensate (DC) is a cluster of cells critical for HF development and regeneration. Events that presage emergence of this distinctive population are poorly understood. Using unbiased single-cell RNA sequencing and in vivo methods, we infer a sequence of transcriptional states through which DC cells pass that begins prior to HF morphogenesis. Our data indicate that Wnt/ß-catenin signaling is required to progress into an intermediate stage that precedes quiescence and differentiation. Further, we provide evidence that quiescent DC cells are recent progeny of selectively proliferating cells present prior to morphogenesis and that are later identified in the peri-DC zone during DC expansion. Together, these findings provide an inferred path of molecular states that lead to DC cell differentiation.


Asunto(s)
Diferenciación Celular/fisiología , Folículo Piloso/citología , Morfogénesis/fisiología , Análisis de la Célula Individual , Dermis/citología , Regulación del Desarrollo de la Expresión Génica/fisiología , Neurogénesis , Piel/metabolismo , Vía de Señalización Wnt/fisiología , beta Catenina/metabolismo
20.
J Cell Mol Med ; 23(3): 1784-1797, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30548903

RESUMEN

Aberrant regulation of programmed cell death (PCD) has been tied to an array of human pathologies ranging from cancers to autoimmune disorders to diverse forms of neurodegeneration. Pharmacologic modulation of PCD signalling is therefore of central interest to a number of clinical and biomedical applications. A key component of PCD signalling involves the modulation of pro- and anti-apoptotic Bcl-2 family members. Among these, Bax translocation represents a critical regulatory phase in PCD. In the present study, we have employed a high-content high-throughput screen to identify small molecules which inhibit the cellular process of Bax re-distribution to the mitochondria following commitment of the cell to die. Screening of 6246 Generally Recognized As Safe compounds from four chemical libraries post-induction of cisplatin-mediated PCD resulted in the identification of 18 compounds which significantly reduced levels of Bax translocation. Further examination revealed protective effects via reduction of executioner caspase activity and enhanced mitochondrial function. Consistent with their effects on Bax translocation, these compounds exhibited significant rescue against in vitro and in vivo cisplatin-induced apoptosis. Altogether, our findings identify a new set of clinically useful small molecules PCD inhibitors and highlight the role which cAMP plays in regulating Bax-mediated PCD.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Proteínas Fluorescentes Verdes/antagonistas & inhibidores , Ensayos Analíticos de Alto Rendimiento/métodos , Transporte de Proteínas/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología , Proteína X Asociada a bcl-2/antagonistas & inhibidores , Animales , Células CHO , Cricetulus , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Proteína X Asociada a bcl-2/metabolismo
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