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1.
J Neurol Surg B Skull Base ; 83(4): 359-366, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35903650

RESUMEN

Introduction Standardized reconstruction protocols for large open anterior skull base defects with dural resection are not well described. Here we report the outcomes and technique of a multilayered reconstructive algorithm utilizing local tissue, dural graft matrix, and microvascular free tissue transfer (MVFTT) for reconstruction of these deformities. Design This study is a retrospective review. Results Eleven patients (82% males) met inclusion criteria, with five (45%) having concurrent orbital exenteration and eight (73%) requiring maxillectomy. All patients required dural resection with or without intracranial tumor resection, with the average dural defect being 36.0 ± 25.9 cm 2 . Dural graft matrices and pericranial flaps were used for primary reconstruction of the dural defects, which were then reinforced with free fascia or muscle overlay by means of MVFTT. Eight (73%) patients underwent anterolateral thigh MVFTT, with the radial forearm, fibula, and vastus lateralis comprising the remainder. Average total surgical time of tumor resection and reconstruction was 14.9 ± 3.8 hours, with median length of hospitalization being 10 days (IQR: 9.5, 14). Continuous cerebrospinal fluid drainage through a lumber drain was utilized in 10 (91%) patients perioperatively, with an average length of indwelling drain of 5 days. Postoperative complications occurred in two (18%) patients who developed asymptomatic pneumocephalus that resolved with high-flow oxygen therapy. Conclusion A standardized multilayered closure technique of dural graft matrix, pericranial flap, and MVFTT overlay in the reconstruction of large open anterior craniofacial dural defects can assist the reconstructive team in approaching these complex deformities and may help prevent postoperative complications.

2.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-498158

RESUMEN

Vitamin D supplementation has been linked to improved outcomes from respiratory virus infection, and the COVID19 pandemic has renewed interest in understanding the potential role of vitamin D in protecting the lung from viral infections. Therefore, we evaluated the role of Vitamin D using animal models of pandemic H1N1 influenza and SARS-CoV-2 infection. In mice, dietary induced vitamin D deficiency resulted in lung inflammation that was present prior to infection. Vitamin D sufficient (D+) and deficient (D-) wildtype (WT) and D+ and D-Cyp27B1 (Cyp) knockout (KO, cannot produce 1,25(OH)2D) mice were infected with pandemic H1N1. D- WT, D+ Cyp KO, and D- Cyp KO mice all exhibited significantly reduced survival compared to D+ WT mice. Importantly, survival was not the result of reduced viral replication as influenza M gene expression in the lungs was similar for all animals. Based on these findings, additional experiments were performed using the mouse and hamster models of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. In these studies, high dose vitamin D supplementation reduced lung inflammation in mice but not hamsters. A trend to faster weight recovery was observed in 1,25(OH)2D treated mice that survived SARS-CoV-2 infection. There was no effect of vitamin D on SARS-CoV-2 N gene expression in the lung of either mice or hamsters. Therefore, vitamin D deficiency enhanced disease severity, while vitamin D sufficient/supplementation reduced inflammation following infections with H1N1 influenza and SARS-CoV-2.

3.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-21262414

RESUMEN

SARS-CoV-2 serosurveys can estimate cumulative incidence for monitoring epidemics but require characterization of employed serological assays performance to inform testing algorithm development and interpretation of results. We conducted a multi-laboratory evaluation of 21 commercial high-throughput SARS-CoV-2 serological assays using blinded panels of 1,000 highly-characterized blood-donor specimens. Assays demonstrated a range of sensitivities (96%-63%), specificities (99%-96%) and precision (IIC 0.55-0.99). Durability of antibody detection in longitudinal samples was dependent on assay format and immunoglobulin target, with anti-spike, direct, or total Ig assays demonstrating more stable, or increasing reactivity over time than anti-nucleocapsid, indirect, or IgG assays. Assays with high sensitivity, specificity and durable antibody detection are ideal for serosurveillance. Less sensitive assays demonstrating waning reactivity are appropriate for other applications, including characterizing antibody responses after infection and vaccination, and detection of anamnestic boosting by reinfections and vaccine breakthrough infections. Assay performance must be evaluated in the context of the intended use.

4.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-434529

RESUMEN

Type I interferon (IFN-I) neutralizing autoantibodies have been found in some critical COVID-19 patients; however, their prevalence and longitudinal dynamics across the disease severity scale, and functional effects on circulating leukocytes remain unknown. Here, in 284 COVID-19 patients, we found IFN-I autoantibodies in 19% of critical, 6% of severe and none of the moderate cases. Longitudinal profiling of over 600,000 peripheral blood mononuclear cells using multiplexed single-cell epitope and transcriptome sequencing from 54 COVID-19 patients, 15 non-COVID-19 patients and 11 non-hospitalized healthy controls, revealed a lack of IFN-I stimulated gene (ISG-I) response in myeloid cells from critical cases, including those producing anti-IFN-I autoantibodies. Moreover, surface protein analysis showed an inverse correlation of the inhibitory receptor LAIR-1 with ISG-I expression response early in the disease course. This aberrant ISG-I response in critical patients with and without IFN-I autoantibodies, supports a unifying model for disease pathogenesis involving ISG-I suppression via convergent mechanisms.

5.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-21254260

RESUMEN

BackgroundAntibody response duration following SARS-CoV-2 infection tends to be variable and depends on severity of disease and method of detection. Study design and methodsCOVID-19 convalescent plasma (CCP) from 18 donors was collected longitudinally for a maximum of 63 - 129 days following resolution of symptoms. All the samples were initially screened by the Ortho Total Ig test to confirm positivity and subsequently tested with 7 additional direct sandwich or indirect binding assays (Ortho, Roche, Abbott, Broad Institute) directed against a variety of antigen targets (S1, RBD, and NC), along with 2 neutralization assays (Broad Institute live virus PRNT and Vitalant Research Institute Pseudovirus RVPN). ResultsThe direct detection assays (Ortho Total Ig total and Roche Total Ig) showed increasing levels of antibodies over the time period, in contrast to the indirect IgG assays that showed a decline. Neutralization assays also demonstrated declining responses; the VRI RVPN pseudovirus had a greater rate of decline than the Broad PRNT live virus assay. DiscussionThese data show that in addition to variable individual responses and associations with disease severity, the detection assay chosen contributes to the heterogeneous results in antibody stability over time. Depending on the scope of the research, one assay may be preferable over another. For serosurveillance studies, direct, double Ag-sandwich assays appear to be the best choice due to their stability; in particular, algorithms that include both S1 and NC based assays can help reduce the rate of false-positivity and discriminate between natural infection and vaccine-derived seroreactivity.

6.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-300871

RESUMEN

A coronavirus antigen microarray (COVAM) was constructed containing 11 SARS-CoV-2, 5 SARS-1, 5 MERS, and 12 seasonal coronavirus recombinant proteins. The array is designed to measure immunoglobulin isotype and subtype levels in serum or plasma samples against each of the individual antigens printed on the array. We probed the COVAM with COVID-19 convalescent plasma (CCP) collected from 99 donors who recovered from a PCR+ confirmed SARS-CoV-2 infection. The results were analyzed using two computational approaches, a generalized linear model (glm) and Random Forest (RF) prediction model, to classify individual specimens as either Reactive or Non-Reactive against the SARS-CoV-2 antigens. A training set of 88 pre-COVID-19 specimens (PreCoV) collected in August 2019 and102 positive specimens from SARS-CoV-2 PCR+ confirmed COVID-19 cases was used for these analyses. Results compared with an FDA emergency use authorized (EUA) SARS-CoV2 S1-based total Ig chemiluminescence immunoassay (Ortho Clinical Diagnostics VITROS(R) Anti-SARS-CoV-2 Total, CoV2T) and with a SARS-CoV-2 S1-S2 spike-based pseudovirus micro neutralization assay (SARS-CoV-2 reporter viral particle neutralization titration (RVPNT) showed high concordance between the 3 assays. Three CCP specimens that were negative by the VITROS CoV2T immunoassay were also negative by both COVAM and the RVPNT assay. Concordance between VITROS CoV2T and COVAM was 96%, VITROS CoV2T and RVPNT 93%, and RVPNT and COVAM 95%. The discordances were all weakly reactive samples near the cutoff threshold of the VITROS CoV2T immunoassay. The multiplex COVAM allows CCP to be grouped according to antibody reactivity patterns against 11 SARS-CoV-2 antigens. Unsupervised K-means analysis, via the gap statistics, as well as hierarchical clustering analysis revealed 3 main clusters with distinct reactivity intensities and patterns. These patterns were not recapitulated by adjusting the VITROS CoV2T or RVPNT assay thresholds. Plasma classified according to these reactivity patterns may be better associated with CCP treatment efficacy than antibody levels alone. The use of a SARS-CoV-2 antigen array may be useful to qualify CCP for administration as a treatment for acute COVID-19 and to interrogate vaccine immunogenicity and performance in preclinical and clinical studies to understand and recapitulate antibody responses associated with protection from infection and disease.

7.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-327187

RESUMEN

<p><b>OBJECTIVE</b>To investigate the effect of gambogic acid (GA) on the growth and cell death of castrate resistant prostate cancer (PC) with phosphate and tension homology (PTEN) and p53 genes deleted in vitro and ex vivo, and elucidate the underlying possible molecular mechanisms.</p><p><b>METHODS</b>PTEN/p53PC cells and Los Angeles prostate cancer-4 (LAPC-4) cells were treated with GA for 24 h and 48 h, then cell viability was determined by cell proliferation assay. PTEN/p53PC cells organoids number was calculated under GA treatment for 1 week. In addition, cell titer glo assay was performed to analyze 3 dimensional cell viability of patients derived xenografts (PDX) 170.2 organoids. Flow cytometry was used to detect apoptotic cells treated with GA. And confocal image was performed to detect the apoptotic mitochondrial morphological changes. Apoptotic cell death related protein levels were measured through Western blot (WB) in GA treated cells and organoids. The expression levels of mitogen-activated protein kinases (MAPKs) pathway related ribonucleic acid (RNAs) and proteins were analyzed by reverse transcription polymerase chain reaction (RT-PCR) and WB, respectively.</p><p><b>RESULTS</b>The treatment of GA significantly reduced cell viability of PTEN/p53PC cells and LAPC-4 in a time- and concentration-dependent manner. In organoids, GA showed strong inhibition towards organoids' numbers and diameters and continuously led to a complete organoids inhibition with GA 150 nmol/L. Ex vivo results validated that GA 1 μmol/L inhibited 44.6% PDX170.2 organoids growth. As for mechanism, flow cytometry detected continuously increased apoptotic portion under GA treatment from 1.98% to 11.78% (6 h) and 29.94% (8 h, P<0.05). In addition, mitochondrial fragmentation emerged in GA treated cells indicated the mitochondrial apoptotic pathway might be involved. Furthermore, WB detected caspases-3, -9 activation and light chain (LC)-3 conversion with GA treatment. WB revealed decreased activity of MAPK pathway and down-regulation of downstream c-fos oncogene RNA level was detected by RT-PCR before undergoing apoptosis (P<0.05).</p><p><b>CONCLUSION</b>GA was a potent anti-tumor compound as for PTEN/p53PC, which contributed to cell apoptosis via inhibition of the MAPK pathway and c-fos.</p>

8.
J Patient Saf ; 10(4): 211-7, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25408999

RESUMEN

OBJECTIVES: Reporting of clinically significant events represents an important mechanism by which patient safety problems may be identified and corrected. However, time pressure and cumbersome report entry procedures have discouraged the full participation of physicians. To improve the process, our internal medicine training program developed an easy-to-use mobile platform that combines the reporting process with patient sign-out. METHODS: Between August 25, 2011, and January 25, 2012, our trainees entered clinically significant events into i-touch/i-phone/i-pad based devices functioning in wireless-synchrony with our desktop application. Events were collected into daily reports that were sent from the handoff system to program leaders and attending physicians to plan for rounds and to correct safety problems. RESULTS: Using the mobile module, residents entered 31 reportable events per month versus the 12 events per month that were reported via desktop during a previous 6-month study period. CONCLUSIONS: Advances in information technology now permit clinically significant events that take place during "off hours" to be identified and reported (via handoff) to next providers and to supervisors via collated reports. This information permits hospital leaders to correct safety issues quickly and effectively, while attending physicians are able to use information gleaned from the reports to optimize rounding plans and to provide additional oversight of trainee on call patient management decisions.


Asunto(s)
Redes de Comunicación de Computadores , Sistemas de Información en Hospital , Medicina Interna , Internado y Residencia , Cuerpo Médico de Hospitales , Daño del Paciente , Seguridad del Paciente , Teléfono Celular , Comunicación , Computadores , Femenino , Humanos , Masculino , Médicos , Mejoramiento de la Calidad
9.
Cell Stem Cell ; 11(4): 541-53, 2012 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-23040480

RESUMEN

In response to muscle injury, satellite cells activate the p38α/ß MAPK pathway to exit quiescence, then proliferate, repair skeletal muscle, and self-renew, replenishing the quiescent satellite cell pool. Although satellite cells are capable of asymmetric division, the mechanisms regulating satellite cell self-renewal are not understood. We found that satellite cells, once activated, enter the cell cycle and a subset undergoes asymmetric division, renewing the satellite cell pool. Asymmetric localization of the Par complex activates p38α/ß MAPK in only one daughter cell, inducing MyoD, which permits cell cycle entry and generates a proliferating myoblast. The absence of p38α/ß MAPK signaling in the other daughter cell prevents MyoD induction, renewing the quiescent satellite cell. Thus, satellite cells employ a mechanism to generate distinct daughter cells, coupling the Par complex and p38α/ß MAPK signaling to link the response to muscle injury with satellite cell self-renewal.


Asunto(s)
División Celular Asimétrica , Moléculas de Adhesión Celular/metabolismo , Células Satélite del Músculo Esquelético/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Animales , Biomarcadores/metabolismo , Moléculas de Adhesión Celular/genética , Proteínas de Ciclo Celular , Línea Celular , Proliferación Celular , Supervivencia Celular , Activación Enzimática/genética , Isoenzimas/genética , Isoenzimas/metabolismo , Sistema de Señalización de MAP Quinasas , Ratones , Complejos Multiproteicos/metabolismo , Desarrollo de Músculos , Proteína MioD/genética , Proteína MioD/metabolismo , Miogenina/metabolismo , Proteína Quinasa C/genética , Proteína Quinasa C/metabolismo
10.
J Cell Biol ; 195(1): 147-63, 2011 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-21949413

RESUMEN

Skeletal muscle contains progenitor cells (satellite cells) that maintain and repair muscle. It also contains muscle side population (SP) cells, which express Abcg2 and may participate in muscle regeneration or may represent a source of satellite cell replenishment. In Abcg2-null mice, the SP fraction is lost in skeletal muscle, although the significance of this loss was previously unknown. We show that cells expressing Abcg2 increased upon injury and that muscle regeneration was impaired in Abcg2-null mice, resulting in fewer centrally nucleated myofibers, reduced myofiber size, and fewer satellite cells. Additionally, using genetic lineage tracing, we demonstrate that the progeny of Abcg2-expressing cells contributed to multiple cell types within the muscle interstitium, primarily endothelial cells. After injury, Abcg2 progeny made a minor contribution to regenerated myofibers. Furthermore, Abcg2-labeled cells increased significantly upon injury and appeared to traffic to muscle from peripheral blood. Together, these data suggest an important role for Abcg2 in positively regulating skeletal muscle regeneration.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Fibras Musculares Esqueléticas/fisiología , Regeneración/fisiología , Células Satélite del Músculo Esquelético/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/genética , Animales , Ratones , Ratones Noqueados , Fibras Musculares Esqueléticas/citología , Células Satélite del Músculo Esquelético/citología
12.
Health Promot Pract ; 11(6): 798-806, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19515862

RESUMEN

Asthma case management and education programs improve pediatric asthma outcomes, but designing rigorous randomized controlled studies that accurately measure effects while encouraging parent participation is challenging. This is especially so for low-income African American families, who face significantly more severe asthma and social stress than their middle-class counterparts. Action research can help health education researchers negotiate between the elegant and complex designs favored by scientists with the real-life challenges of recruitment, implementation, and retention. This article discusses how a multidisciplinary team uses action research concepts to continuously adjust originally proposed protocols through the planning and implementation phases to encourage participation in a year-long randomized controlled trial of a program that combines telephone asthma case management and comprehensive online asthma education. As a result of these efforts, a higher proportion of low-income African American families are recruited into the study than originally proposed.


Asunto(s)
Asma/terapia , Manejo de Caso/organización & administración , Investigación Participativa Basada en la Comunidad/métodos , Educación en Salud/métodos , Internet , Negro o Afroamericano/estadística & datos numéricos , Asma/etnología , Niño , Conducta Cooperativa , Humanos , Medicaid/estadística & datos numéricos , Cumplimiento de la Medicación/estadística & datos numéricos , Grupo de Atención al Paciente/organización & administración , Selección de Paciente , Áreas de Pobreza , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Proyectos de Investigación , Teléfono , Estados Unidos
13.
Cell Stem Cell ; 4(3): 217-25, 2009 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-19265661

RESUMEN

Skeletal muscle satellite cells, located between the basal lamina and plasma membrane of myofibers, are required for skeletal muscle regeneration. The capacity of satellite cells as well as other cell lineages including mesoangioblasts, mesenchymal stem cells, and side population (SP) cells to contribute to muscle regeneration has complicated the identification of a satellite stem cell. We have characterized a rare subset of the muscle SP that efficiently engrafts into the host satellite cell niche when transplanted into regenerating muscle, providing 75% of the satellite cell population and 30% of the myonuclear population, respectively. These cells are found in the satellite cell position, adhere to isolated myofibers, and spontaneously undergo myogenesis in culture. We propose that this subset of SP cells (satellite-SP cells), characterized by ABCG2, Syndecan-4, and Pax7 expression, constitutes a self-renewing muscle stem cell capable of generating both satellite cells and their myonuclear progeny in vivo.


Asunto(s)
Músculo Esquelético/fisiología , Regeneración , Células Satélite del Músculo Esquelético/fisiología , Células Satélite del Músculo Esquelético/trasplante , Nicho de Células Madre/fisiología , Sindecano-4/biosíntesis , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/biosíntesis , Animales , Femenino , Ratones , Ratones Endogámicos C57BL , Desarrollo de Músculos , Factor de Transcripción PAX7/biosíntesis , Células Satélite del Músculo Esquelético/metabolismo , Sindecano-3/biosíntesis
14.
Health Promot Pract ; 8(3): 282-91, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16928987

RESUMEN

This article reports on the development of a personalized, Web-based asthma-education program for parents whose 4- to 12-year-old children have moderate to severe asthma. Personalization includes computer-based tailored messages and a human coach to build asthma self-management skills. Computerized features include the Asthma Manager, My Calendar/Reminder, My Goals, and a tailored home page. These are integrated with monthly asthma-education phone calls from an asthma-nurse case manager. The authors discuss the development process and issues and describe the current randomized evaluation study to test whether the year-long integrated intervention can improve adherence to a daily asthma controller medication, asthma control, and parent quality of life to reduce asthma-related healthcare utilization. Implications for health education for chronic disease management are raised.


Asunto(s)
Asma/prevención & control , Manejo de Caso , Educación en Salud/métodos , Internet , Padres/educación , Telemedicina/métodos , Teléfono , Niño , Preescolar , Enfermedad Crónica , Familia , Femenino , Humanos , Masculino , Aceptación de la Atención de Salud , Grupo de Atención al Paciente/organización & administración , Participación del Paciente , Relaciones Profesional-Familia , Autocuidado/métodos , Perfil de Impacto de Enfermedad , Integración de Sistemas , Estados Unidos
15.
Learn Behav ; 33(4): 479-500, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16573218

RESUMEN

Acquisition, extinction, and transfer of facilitation were explored in a series of experiments with C57BL/6J mice. With a procedure in which an auditory target was followed by food only in the presence of a visual facilitator, Experiments 1-4 showed that the facilitator promoted magazine entries to the auditory target. This enhancement effect was eliminated by training the facilitator as a conditioned inhibitor (Experiments 1 and 3B). Enhancement was also reduced by nonreinforced presentations of the facilitator in a discrimination procedure (Experiment 1) and by simple nonreinforcement of the facilitator (Experiments 2, 3A, and 4). In contrast to the results obtained with a facilitator, simple nonreinforcement of an inhibitor, a visual cue that had signaled when an auditory target would not be reinforced, did not reduce its ability to modulate responding to that target (Experiment 4). However, both the facilitator and the inhibitor were found to transfer their modulatory effects to other targets (Experiment 4). Finally, mice demonstrated no evidence of differential responding on a biconditional discrimination procedure in which one auditory target (A1) was reinforced in the presence of one visual stimulus (L1) but not in the presence of another (L2), and a different auditory target (A2) was reinforced in L2 but not in L1 (Experiment 5). The implications of these results for analysis of the function of a facilitator are discussed.


Asunto(s)
Conducta Animal , Condicionamiento Psicológico , Extinción Psicológica , Aprendizaje , Facilitación Social , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL
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