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1.
Development ; 150(5)2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36897355

RESUMEN

Neurogenesis is initiated by basic helix-loop-helix proneural proteins. Here, we show that Actin-related protein 6 (Arp6), a core component of the H2A.Z exchange complex SWR1, interacts with proneural proteins and is crucial for efficient onset of proneural protein target gene expression. Arp6 mutants exhibit reduced transcription in sensory organ precursors (SOPs) downstream of the proneural protein patterning event. This leads to retarded differentiation and division of SOPs and smaller sensory organs. These phenotypes are also observed in proneural gene hypomorphic mutants. Proneural protein expression is not reduced in Arp6 mutants. Enhanced proneural gene expression fails to rescue retarded differentiation in Arp6 mutants, suggesting that Arp6 acts downstream of or in parallel with proneural proteins. H2A.Z mutants display Arp6-like retardation in SOPs. Transcriptomic analyses demonstrate that loss of Arp6 and H2A.Z preferentially decreases expression of proneural protein-activated genes. H2A.Z enrichment in nucleosomes around the transcription start site before neurogenesis correlates highly with greater activation of proneural protein target genes by H2A.Z. We propose that upon proneural protein binding to E-box sites, H2A.Z incorporation around the transcription start site allows rapid and efficient activation of target genes, promoting rapid neural differentiation.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Activación Transcripcional , Actinas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Histonas/metabolismo , Nucleosomas/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo
2.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34544873

RESUMEN

The biological mechanisms underpinning learning are unclear. Mounting evidence has suggested that adult hippocampal neurogenesis is involved although a causal relationship has not been well defined. Here, using high-resolution genetic mapping of adult neurogenesis, combined with sequencing information, we identify follistatin (Fst) and demonstrate its involvement in learning and adult neurogenesis. We confirmed that brain-specific Fst knockout (KO) mice exhibited decreased hippocampal neurogenesis and demonstrated that FST is critical for learning. Fst KO mice exhibit deficits in spatial learning, working memory, and long-term potentiation (LTP). In contrast, hippocampal overexpression of Fst in KO mice reversed these impairments. By utilizing RNA sequencing and chromatin immunoprecipitation, we identified Asic4 as a target gene regulated by FST and show that Asic4 plays a critical role in learning deficits caused by Fst deletion. Long-term overexpression of hippocampal Fst in C57BL/6 wild-type mice alleviates age-related decline in cognition, neurogenesis, and LTP. Collectively, our study reveals the functions for FST in adult neurogenesis and learning behaviors.


Asunto(s)
Canales Iónicos Sensibles al Ácido/metabolismo , Folistatina/fisiología , Hipocampo/metabolismo , Neurogénesis , Plasticidad Neuronal , Aprendizaje Espacial/fisiología , Canales Iónicos Sensibles al Ácido/genética , Animales , Cognición , Femenino , Potenciación a Largo Plazo , Masculino , Memoria , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Sinapsis/fisiología
3.
Int J Mol Sci ; 25(11)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38892173

RESUMEN

A-to-I RNA editing, catalyzed by the ADAR protein family, significantly contributes to the diversity and adaptability of mammalian RNA signatures, aligning with developmental and physiological needs. Yet, the functions of many editing sites are still to be defined. The Unc80 gene stands out in this context due to its brain-specific expression and the evolutionary conservation of its codon-altering editing event. The precise biological functions of Unc80 and its editing, however, are still largely undefined. In this study, we first demonstrated that Unc80 editing occurs in an ADAR2-dependent manner and is exclusive to the brain. By employing the CRISPR/Cas9 system to generate Unc80 knock-in mouse models that replicate the natural editing variations, our findings revealed that mice with the "gain-of-editing" variant (Unc80G/G) exhibit heightened basal neuronal activity in critical olfactory regions, compared to the "loss-of-editing" (Unc80S/S) counterparts. Moreover, an increase in glutamate levels was observed in the olfactory bulbs of Unc80G/G mice, indicating altered neurotransmitter dynamics. Behavioral analysis of odor detection revealed distinctive responses to novel odors-both Unc80 deficient (Unc80+/-) and Unc80S/S mice demonstrated prolonged exploration times and heightened dishabituation responses. Further elucidating the olfactory connection of Unc80 editing, transcriptomic analysis of the olfactory bulb identified significant alterations in gene expression that corroborate the behavioral and physiological findings. Collectively, our research advances the understanding of Unc80's neurophysiological functions and the impact of its editing on the olfactory sensory system, shedding light on the intricate molecular underpinnings of olfactory perception and neuronal activity.


Asunto(s)
Adenosina Desaminasa , Percepción Olfatoria , Edición de ARN , Animales , Ratones , Percepción Olfatoria/fisiología , Adenosina Desaminasa/metabolismo , Adenosina Desaminasa/genética , Bulbo Olfatorio/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Neuronas/metabolismo , Sistemas CRISPR-Cas , Masculino , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo
4.
Med Teach ; 45(4): 368-374, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36288746

RESUMEN

BACKGROUND: The ability of medical students to speak up before a medical error occurs is a timely and necessary interaction to prevent potential patient harm. As it may be crucial to improve patient safety, we explored how medical students react to a medical error and provided them appropriate training regarding speaking up about medical issues. METHODS: A quasi-experimental study was conducted in Taiwan involving 153 medical students who participated in a speaking-up simulation course. They were divided into two groups. The first group participated in a non-life-threatening scenario before the intervention, followed by a personalized debriefing session, then a life-threatening scenario after the intervention. The second group participated in a life-threatening scenario before the intervention, followed by a personalized debriefing session, then a non-life-threatening scenario after the intervention. Students also completed patient safety attitude survey. RESULTS: During the preintervention scenario, the overall medical students' speaking-up rate to medical error was 45.1%. The speaking-up rate of medical students in life-threatening scenario was significantly higher than the rate in non-life-threatening scenario before the intervention (64.6% vs 24.3%, p < 0.001). After personalized debriefing, the speaking-up rate to medical errors was significantly improved both in life-threatening scenarios (95.9%, p < 0.001) and in non-life-threatening scenarios (100%, p < 0.001). Male medical students had significantly higher speaking-up rates than female students in life-threatening scenario (76.2% vs 51.4%, p = 0.02). On post-intervention surveys, students provided several reasons for their likelihood of speaking up or remaining silent during a medical error event. CONCLUSIONS: Medical students' rate of speaking-up to medical error was higher in a simulated life-threatening scenario than in a simulated non-life-threatening scenario. Faculty-led personalized debriefing can facilitate medical students' adoption of communication strategies to speak up more in medical error events. Educators should also consider gender differences when they design effective assertive communication courses.[Box: see text].


Asunto(s)
Entrenamiento Simulado , Estudiantes de Medicina , Humanos , Masculino , Femenino , Errores Médicos/prevención & control , Comunicación , Seguridad del Paciente
5.
BMC Oral Health ; 23(1): 800, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37884939

RESUMEN

BACKGROUND: Gingival papilla defects, which cause an unpleasant appearance and involve the upper anterior teeth, may be triggered by several factors. Several noninvasive and invasive techniques have been proposed for gingival papilla reconstruction. The combination of interproximal tunneling and customized connective tissue grafts (CTGs) has shown promise in papilla augmentation. However, due to the narrowness and limited blood supply of the gingival papilla, the long-term outcomes of these techniques remain unpredictable. Therefore, achieving tension-free coronal advancement of the interdental papilla and proper placement of the CTG is crucial for successful long-term outcomes and could provide widely applicable methods for papilla augmentation. CASE REPORT: In this study, we enrolled three patients with gingival papilla defects in the maxillary anterior teeth. For reconstruction, we proposed a modified interproximal tunneling (MIPT) technique combined with a CTG. A crucial modification based on previous studies involved adding a cutback incision to the base of the palatal vertical incision, resulting in tension-free healing. Additionally, the CTG was sutured upright to further enhance the height of the gingiva papilla. To evaluate the efficacy of the MIPT technique, the clinical parameters-including the Jemt papilla index and the distance from the tip of the papilla to the interproximal contact point-were examined using a periodontal probe (UNC15, Hu-friedy) at baseline and 12 months after surgery. All three patients achieved satisfactory papilla reconstruction 12 months after the surgery. These three cases were used to evaluate the efficacy of the MIPT technique combined with the customized CTG. An average increase in the Jemt papilla score from 1.6 to 2.8 and a reduction in the distance from the papilla tip to the contact point of adjacent teeth from 2 mm to 0.08 mm were observed 12 months after surgery. CONCLUSION: The preliminary results confirmed that this technique holds promise for gingival papilla augmentation between tooth/tooth or tooth/implant.


Asunto(s)
Implantes Dentales , Diente , Humanos , Encía/cirugía , Cicatrización de Heridas , Tejido Conectivo/trasplante
6.
BMC Vet Res ; 18(1): 258, 2022 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-35790990

RESUMEN

BACKGROUND: Bronchiolar disorders are rarely recognized in cats. Constrictive bronchiolitis obliterans is characterized by concentric peribronchiolar fibrosis and inflammation of the bronchioles, but the underlying causes remain poorly understood in current small animal medicine. CASE PRESENTATION: A 9-year-old cat presented with paroxysmal tachypnea, infrequent cough and persistent labor breathing. Thoracic radiography showed lung hyperinflation and bronchointerstitial pattern, and pulmonary function assessment revealed flow limitation in the late-expiratory phase and poor response to short-acting bronchodilator. Dorsally distributed subpleural ground glass opacities with distinct margin and tree-in-bud opacities were observed on lung high-resolution computed tomography. The cat underwent bronchoalveolar lavage (BAL) and showed severe neutrophilic inflammation. Feline herpesvirus was the only pathogen detected in the BAL fluid. Multiple therapeutic attempts were unsuccessful and the cat died 8 weeks after the initial presentation. Necropsy revealed the infiltration of inflammatory cells, obstruction of the bronchiolar lumen, and submucosal concentric fibrosis suggesting constrictive bronchiolitis obliterans. Combining the pre- and post-mortem findings, as well as the time from symptom onset or BAL to necropsy, constrictive bronchiolitis obliterans was possibly triggered by a preceding feline herpesvirus infection in this case. CONCLUSIONS: The history of nonvaccinated status, lower airway neutrophilic inflammation, and presence of feline herpesvirus in the BAL fluid without coexistence of other pathogens led to the presumption that constrictive bronchiolitis obliterans was induced by a preceding feline herpesvirus infection in this cat. The pathological changes of bronchiolitis obliterans induced by a preceding feline herpesvirus infection could be different from that of cats with acute herpesvirus pneumonia, such as intranuclear inclusions would disappear over time and were no longer found 7-10 days after inoculation. The presence of patchy distribution of subpleural ground glass opacities on lung high-resolution computed tomography should raise the suspicion of peribronchiolar fibrosis. Clinical awareness of bronchiolar disorders as a differential diagnosis is important in cats with lung hyperinflation and labored breathing who show poor reversibility to bronchodilator.


Asunto(s)
Bronquiolitis Obliterante , Enfermedades de los Gatos , Infecciones por Herpesviridae , Animales , Bronquiolitis Obliterante/diagnóstico por imagen , Bronquiolitis Obliterante/etiología , Bronquiolitis Obliterante/veterinaria , Broncodilatadores , Enfermedades de los Gatos/diagnóstico , Enfermedades de los Gatos/etiología , Gatos , Constricción Patológica/veterinaria , Fibrosis , Infecciones por Herpesviridae/complicaciones , Infecciones por Herpesviridae/veterinaria , Inflamación/veterinaria , Varicellovirus
7.
Med Teach ; 44(1): 38-44, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34477475

RESUMEN

BACKGROUND: Training medical students to speak up when they witness a potential error is an important competency for patient safety, but details regarding the barriers that prevent medical students from effectively communicating are lacking. Therefore, this study aimed at exploring the factors affecting medical students' willingness to speak up for patient safety when a medical error was observed. METHODS: This is a cross-sectional study at a medical university in Taiwan, and 151 medical students in clinical clerkship completed a survey including demographic characteristics, conflict of interests/social relationship, personal capability, and personality and characteristics of senior staff domains. Data were analyzed using t-test. RESULTS: Three of five items in the conflict of interests/social relationship domain showed statistically significant importance, including 'I am afraid of being punished' (Mean difference, MD = 0.37; p < 0.01), 'I do not want to break unspoken rules' (MD = 0.55; p < 0.01), and 'I do not want to have bad team relationship' (MD = 0.58; p < 0.01). Two items (perception of knowledge/understanding and communication skills) in the personal capability domain were significantly important to speaking up. Six of 10 items in personality and characteristics of senior staff domain were rated significantly important in deciding to speak up. The top three factors of them were senior personnel with 'Grumpy' personality (MD = 1.20; p < 0.01), 'hierarchy gap' (MD = 1.12; p < 0.01), and senior personnel with 'Stubborn' personality (MD = 1.06; p < 0.01). CONCLUSION: Our findings demonstrated medical students' perspectives on barriers to speaking up in the event of medical error. Some factors related to characteristics of senior staff could compromise medical students' ability to speak up in the event of medical error. These results might be important for medical educators in designing personalized educational activities related to medical students' ability to speak up for patient safety.


Asunto(s)
Prácticas Clínicas , Educación de Pregrado en Medicina , Estudiantes de Medicina , Estudios Transversales , Curriculum , Humanos , Errores Médicos/prevención & control , Encuestas y Cuestionarios
8.
BMC Med Educ ; 22(1): 651, 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-36042449

RESUMEN

BACKGROUND: Interprofessional collaborative practice is essential for meeting patients' needs and improving their health outcomes; thus, the effectiveness of interprofessional education (IPE) should be clearly identified. There is insufficient evidence in the literature to determine the outcomes of IPE compared to traditional single-profession education (SPE). This study aimed to compare the outcomes of IPE and SPE during a simulation training course. METHODS: The study design was a mixed-methods, incorporated cross-over design and a qualitative survey. A total of 54 students including 18 medical students and 36 nursing students were recruited from March to April 2019. The 4-week simulation course was designed based on Kolb's experimental learning theory and Bandura's social learning theory. Participants were evenly divided into group 1 (received IPE-learning followed by SPE-learning), and group 2 (received SPE-learning followed by IPE-learning). Students' medical task performance, team behavior performance, teamwork attitude, and patient safety attitude were collected at pretest, mid-test, and posttest. Descriptive statistics and repeated measures analysis of variance were used. End-of-study qualitative feedback was collected, and content analysis was performed. RESULTS: Both groups demonstrated moderate-to-large within-group improvements for multiple learning outcomes at mid-test. Group 1 students' medical task performance (F = 97.25; P < 0.001) and team behavior performance (F = 31.17; P < 0.001) improved significantly. Group 2 students' medical task performance (F = 77.77; P < 0.001), team behavior performance (F = 40.14; P < 0.001), and patient safety attitude (F = 6.82; P < 0.01) improved significantly. Outcome differences between groups were nonsignificant. Qualitative themes identified included: personal factor, professional factor, interprofessional relationship, and learning. The IPE program provided students with exposure to other professions and revealed differences in expertise and responsibilities. CONCLUSION: IPE-simulation and SPE-simulation were effective interventions that enabled medical and nursing students to develop critical medical management and team behavior performance. IPE-simulation provided more opportunities for improving competencies in interprofessional collaborative practice. In circumstances with limited teaching resources, SPE-simulation can be an acceptable alternative to IPE-simulation.


Asunto(s)
Estudiantes de Medicina , Estudiantes de Enfermería , Actitud del Personal de Salud , Humanos , Educación Interprofesional , Relaciones Interprofesionales , Aprendizaje
9.
EMBO Rep ; 20(5)2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30948460

RESUMEN

Adenosine deaminase acting on RNA (ADAR)-catalyzed adenosine-to-inosine RNA editing is potentially dysregulated in neoplastic progression. However, how this transcriptome recoding process is functionally correlated with tumorigenesis remains largely elusive. Our analyses of RNA editome datasets identify hypoxia-related genes as A-to-I editing targets. In particular, two negative regulators of HIF-1A-the natural antisense transcript HIF1A-AS2 and the ubiquitin ligase scaffold LIMD1-are directly but differentially modulated by ADAR1. We show that HIF1A-AS2 antagonizes the expression of HIF-1A in the immediate-early phase of hypoxic challenge, likely through a convergent transcription competition in cis ADAR1 in turn suppresses transcriptional progression of the antisense gene. In contrast, ADAR1 affects LIMD1 expression post-transcriptionally, by interfering with the cytoplasmic translocation of LIMD1 mRNA and thus protein translation. This multi-tier regulation coordinated by ADAR1 promotes robust and timely accumulation of HIF-1α upon oxygen depletion and reinforces target gene induction and downstream angiogenesis. Our results pinpoint ADAR1-HIF-1α axis as a hitherto unrecognized key regulator in hypoxia.


Asunto(s)
Adenosina Desaminasa/genética , Hipoxia de la Célula/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Proteínas de Unión al ARN/genética , Transducción de Señal/genética , Carcinogénesis/genética , Línea Celular Tumoral , Citoplasma/genética , Humanos , Proteínas con Dominio LIM/genética , Células MCF-7 , Edición de ARN/genética , ARN Mensajero/genética , Transcripción Genética/genética
10.
Appl Microbiol Biotechnol ; 105(11): 4663-4673, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34043078

RESUMEN

The recent Zika virus (ZIKV) epidemic poses a serious threat to global health due to its association with microcephaly and congenital diseases in newborns and neurological complications and Guillain-Barré syndrome in adults. However, the majority of people infected with ZIKV do not develop symptoms. The platforms aimed to specifically diagnose ZIKV infection are needed for patient care and public health surveillance. In the study, four ZIKV envelope (E) protein-specific monoclonal antibodies (mAbs) (A1, B1, C1, and 9E-1) have been developed by using the conventional mAb technology. The binding epitopes of mAbs A1, B1, C1, and 9E-1 are located at E(238-257), E(410-431), E(258-277), and E(340-356), respectively. mAb 9E-1 performs 1.4- to 47-fold strong affinity to ZIKV E protein compared to another three mAbs. mAbs A1, C1, and 9E-1 do not have cross-reactivity against the recombinant E proteins of dengue virus serotypes 2, 3, and 4. Although these four mAbs do not have ZIKV neutralizing activity, mAbs B1 and 9E-1 have been developed as the lateral flow immunochromatographic assay for specific detection of ZIKV E protein and virions. KEY POINTS: • The mAbs targeting to the regions of E(238-257), E(410-431), E(258-277), and E(340-356) do not have ZIKV neutralizing activity. • The binding epitope of mAb 9E-1 is highly specific to ZIKV E protein. • mAbs B1 and 9E-1 can bind to ZIKV virions and have been developed as the lateral flow immunochromatographic assay.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Adulto , Animales , Anticuerpos Monoclonales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Epítopos , Humanos , Recién Nacido , Ratones , Envoltura Viral , Proteínas del Envoltorio Viral , Infección por el Virus Zika/diagnóstico
11.
Appl Microbiol Biotechnol ; 105(8): 3235-3248, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33770244

RESUMEN

Many cases of avian influenza A(H7N9) virus infection in humans have been reported since its first emergence in 2013. The disease is of concern because most patients have become severely ill with roughly 30% mortality rate. Because the threat in public health caused by H7N9 virus remains high, advance preparedness is essentially needed. In this study, the recombinant H7N9 hemagglutinin (HA) was expressed in insect cells and purified for generation of two monoclonal antibodies, named F3-2 and 1C6B. F3-2 can only recognize the H7N9 HA without having cross-reactivity with HA proteins of H1N1, H3N2, H5N1, and H7N7. 1C6B has the similar specificity with F3-2, but 1C6B can also bind to H7N7 HA. The binding epitope of F3-2 is mainly located in the region of H7N9 HA(299-307). The binding epitope of 1C6B is located in the region of H7N9 HA(489-506). F3-2 and 1C6B could not effectively inhibit the hemagglutination activity of H7N9 HA. However, F3-2 can prevent H7N9 HA from trypsin cleavage and can bind to H7N9 HA which has undergone pH-induced conformational change. F3-2 also has the ability of binding to H7N9 viral particles and inhibiting H7N9 virus infection to MDCK cells with the IC50 value of 22.18 µg/mL. In addition, F3-2 and 1C6B were utilized for comprising a lateral flow immunochromatographic test strip for specific detection of H7N9 HA. KEY POINTS: • Two mouse monoclonal antibodies, F3-2 and 1C6B, were generated for recognizing the novel binding epitopes in H7N9 HA. • F3-2 can prevent H7N9 HA from trypsin cleavage and inhibit H7N9 virus infection to MDCK cells. • F3-2 and 1C6B were developed as a lateral flow immunochromatographic test for specific detection of H7N9 HA.


Asunto(s)
Subtipo H7N9 del Virus de la Influenza A , Gripe Humana , Animales , Anticuerpos Monoclonales , Anticuerpos Antivirales , Glicoproteínas Hemaglutininas del Virus de la Influenza , Hemaglutininas , Humanos , Subtipo H1N1 del Virus de la Influenza A , Subtipo H3N2 del Virus de la Influenza A , Subtipo H5N1 del Virus de la Influenza A , Subtipo H7N7 del Virus de la Influenza A , Gripe Humana/prevención & control , Ratones
12.
Int J Mol Sci ; 22(20)2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34681622

RESUMEN

Phosphatidylinositol 3-kinase catalytic subunit type 3 (PIK3C3), the mammalian ortholog of yeast vesicular protein sorting 34 (Vps34), belongs to the phosphoinositide 3-kinase (PI3K) family. PIK3C3 can phosphorylate phosphatidylinositol (PtdIns) to generate phosphatidylinositol 3-phosphate (PI3P), a phospholipid central to autophagy. Inhibition of PIK3C3 successfully inhibits autophagy. Autophagy maintains cell survival when modifications occur in the cellular environment and helps tumor cells resist metabolic stress and cancer treatment. In addition, PIK3C3 could induce oncogenic transformation and enhance tumor cell proliferation, growth, and invasion through mechanisms independent of autophagy. This review addresses the structural and functional features, tissue distribution, and expression pattern of PIK3C3 in a variety of human tumors and highlights the underlying mechanisms involved in carcinogenesis. The implications in cancer biology, patient prognosis prediction, and cancer therapy are discussed. Altogether, the discovery of pharmacological inhibitors of PIK3C3 could reveal novel strategies for improving treatment outcomes for PIK3C3-mediated human diseases.


Asunto(s)
Fosfatidilinositol 3-Quinasas Clase III/metabolismo , Neoplasias/patología , Autofagia , Proliferación Celular , Fosfatidilinositol 3-Quinasas Clase III/antagonistas & inhibidores , Fosfatidilinositol 3-Quinasas Clase III/genética , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias/metabolismo , Células Madre Neoplásicas/citología , Células Madre Neoplásicas/metabolismo , Dominios Proteicos
13.
Adv Funct Mater ; 29(28): 1807616, 2019 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-32313544

RESUMEN

The continued threat of emerging, highly lethal infectious pathogens such as Middle East respiratory syndrome coronavirus (MERS-CoV) calls for the development of novel vaccine technology that offers safe and effective prophylactic measures. Here, a novel nanoparticle vaccine is developed to deliver subunit viral antigens and STING agonists in a virus-like fashion. STING agonists are first encapsulated into capsid-like hollow polymeric nanoparticles, which show multiple favorable attributes, including a pH-responsive release profile, prominent local immune activation, and reduced systemic reactogenicity. Upon subsequent antigen conjugation, the nanoparticles carry morphological semblance to native virions and facilitate codelivery of antigens and STING agonists to draining lymph nodes and immune cells for immune potentiation. Nanoparticle vaccine effectiveness is supported by the elicitation of potent neutralization antibody and antigen-specific T cell responses in mice immunized with a MERS-CoV nanoparticle vaccine candidate. Using a MERS-CoV-permissive transgenic mouse model, it is shown that mice immunized with this nanoparticle-based MERS-CoV vaccine are protected against a lethal challenge of MERS-CoV without triggering undesirable eosinophilic immunopathology. Together, the biocompatible hollow nanoparticle described herein provides an excellent strategy for delivering both subunit vaccine candidates and novel adjuvants, enabling accelerated development of effective and safe vaccines against emerging viral pathogens.

14.
RNA Biol ; 16(9): 1263-1274, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31135270

RESUMEN

The innate immune system is the frontline host protection against pathogens. Effective antiviral immunity is elicited upon recognition of viral RNAs by the host pattern recognition receptors. One of the major viral RNA sensors is retinoic acid inducible gene-1, which triggers the production of interferons (IFNs). In turn, this protective response requires another viral sensor and immunity factor interferon-inducible protein kinase RNA activator (PACT/PRKRA). Here, we report the identification and characterization of a novel antisense PACT gene that expresses a non-coding RNA in a convergent and interferon-inducible manner. Publicly available gene structure and expression data revealed that this gene, that we termed ASPACT, overlaps with the 3' -end of the PACT locus and is highly expressed during viral infection. Our results confirm the IFN-ß-inducibility of ASPACT, which is dependent on STAT-1/2. We further discovered that downregulation of ASPACT impacts both the expression and localization of the PACT transcript. At the transcription level, ChIP and ChIRP assays demonstrated that the ASPACT non-coding RNA occupies distinct chromatin regions of PACT gene and is important for promoter recruitment of the epigenetic silencer HDAC1. In parallel, ASPACT was also found to mediate nuclear retention of the PACT mRNA via direct RNA-RNA interaction, as revealed by RNA antisense purification assay. In summary, our results support the model that the non-coding RNA ASPACT acts as a negative regulator of PACT at multiple levels, and reveal a novel regulator of the viral counteractive response.


Asunto(s)
ARN sin Sentido/metabolismo , Proteínas de Unión al ARN/metabolismo , Transducción de Señal , Núcleo Celular/metabolismo , Epigénesis Genética , Células HEK293 , Células HeLa , Histona Desacetilasa 1/metabolismo , Humanos , Inmunidad Innata , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/genética , Transcripción Genética
15.
BMC Vet Res ; 15(1): 428, 2019 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-31783850

RESUMEN

BACKGROUND: Babesia gibsoni (B. gibsoni) is an intraerythrocytic protozoan parasite of dogs that causes fever and hemolytic illness. A timely diagnosis is essential for the disease management. RESULTS: Here, we report a QubeMDx PCR system which enables a rapid, sensitive and reliable diagnosis of B. gibsoni near the dog patient. Within 30 min, this diagnostic assay was able to detect as low as 0.002% parasitemia of the dog blood. Using clinical samples, this new assay was validated to demonstrate 100% agreement with real-time PCR. CONCLUSIONS: This novel diagnostic method provides a reliable point-of-care test to assist in the identification of B. gibsoni.


Asunto(s)
Babesia/aislamiento & purificación , Babesiosis/diagnóstico , Enfermedades de los Perros/diagnóstico , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Animales , Babesiosis/sangre , Babesiosis/parasitología , Enfermedades de los Perros/sangre , Enfermedades de los Perros/parasitología , Perros , Sistemas de Atención de Punto , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Sensibilidad y Especificidad
16.
Int J Mol Sci ; 20(9)2019 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-31064083

RESUMEN

Avian infectious bronchitis virus (IBV) causes considerable economic losses in the poultry industry worldwide, including Taiwan. IBV is among the most important pathogens in chickens, and it spreads rapidly among flocks. In addition to dozens of known serotypes, new viral variants have emerged due to the viral evolution and antigenic variation in IBVs. Therefore, the development of a sensitive, specific, and easily performed assay is crucial for the rapid detection and surveillance of IBV infections. A rapid and simple immunochromatographic strip (ICS) was developed in this study by employing monoclonal antibodies against spike and nucleocapsid proteins of IBV as the tracer and the capture antibody. The ICS showed high specificity in detecting IBV antigens, including several IBV genotypes and novel variants, as opposed to three other common avian respiratory viruses. The detection limit of the strip reached 104.4 50% embryo-infective dose. Moreover, in the experimental chicken model, the strip test demonstrated consistency in detecting IBV with RT-PCR gene detection. Taken together, this antigen detection strip has the potential to serve as an on-farm rapid test for IBV; therefore, it may facilitate surveillance and control of the disease.


Asunto(s)
Infecciones por Coronavirus/diagnóstico , Virus de la Bronquitis Infecciosa/inmunología , Técnicas de Diagnóstico Molecular/veterinaria , Enfermedades de las Aves de Corral/diagnóstico , Animales , Antígenos Virales/inmunología , Pollos , Infecciones por Coronavirus/veterinaria , Infecciones por Coronavirus/virología , Femenino , Inmunoensayo/métodos , Inmunoensayo/normas , Inmunoensayo/veterinaria , Ratones , Ratones Endogámicos BALB C , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/normas , Enfermedades de las Aves de Corral/virología , Tiras Reactivas/normas
17.
Int J Mol Sci ; 20(19)2019 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-31569419

RESUMEN

MicroRNAs (miRNAs) dysregulation contribute the cancer pathogenesis. However, the miRNA profile of canine oral melanoma (COM), one of the frequent malignant melanoma in dogs is still unrevealed. The aim of this study is to reveal the miRNA profile in canine oral melanoma. MiRNAs profile of oral tissues from normal healthy dogs and COM patients were compared by next-generation sequencing. Along with tumour suppressor miRNAs, we report 30 oncogenic miRNAs in COM. The expressions of miRNAs were further confirmed by quantitative real-time PCR (qPCR). Pathway analysis showed that deregulated miRNAs impact on cancer and signalling pathways. Three oncogenic miRNAs targets (miR-450b, 301a, and 223) from human study also were down-regulated in COM and had a significant negative correlation with their respective miRNA. Furthermore, we found that miR-450b expression is higher in metastatic cells and regulated MMP9 expression through a PAX9-BMP4-MMP9 axis. In silico analysis indicated that miR-126, miR-20b, and miR-106a regulated the highest numbers of differentially expressed transcription factors with respect to human melanoma. Chromosomal enrichment analysis revealed the X chromosome was enriched with oncogenic miRNAs. We comprehensively analyzed the miRNA's profile in COM which will be a useful resource for developing therapeutic interventions in both species.


Asunto(s)
Enfermedades de los Perros/genética , Melanoma/veterinaria , MicroARNs/genética , Neoplasias de la Boca/veterinaria , Transcriptoma , Animales , Perros , Perfilación de la Expresión Génica , Ontología de Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Reproducibilidad de los Resultados
19.
BMC Biotechnol ; 17(1): 2, 2017 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-28061848

RESUMEN

BACKGROUND: Human infection with avian influenza A virus (H7N9) was first reported in China in March 2013. Since then, hundreds of cases have been confirmed showing severe symptoms with a high mortality rate. The virus was transmitted from avian species to humans and has spread to many neighboring areas, raising serious concerns over its pandemic potential. Towards containing the disease, the goal of this study is to prepare a virus-like particle (VLP) that consists of hemagglutinin (HA), neuraminidase (NA) and matrix protein 1 (M1) derived from the human isolate A/Taiwan/S02076/2013(H7N9) for potential vaccine development. RESULTS: Full length HA, NA, and M1 protein genes were cloned and expressed using a baculoviral expression system, and the VLPs were generated by co-infecting insect cells with three respective recombinant baculoviruses. Nanoparticle tracking analysis and transmission electron microscopy were applied to verify the VLPs' structure and antigenicity, and the multiplicity of infection of the recombinant baculoviruses was adjusted to achieve the highest hemagglutination activity. In animal experiments, BALB/c mice and specific-pathogen-free chickens receiving the VLP immunization showed elevated hemagglutination inhibition serum titer and antibodies against NA and M1 proteins. In addition, examination of cellular immunity showed the VLP-immunized mice and chickens exhibited an increased splenic antigen-specific cytokines production. CONCLUSIONS: The H7N9 VLPs possess desirable immunogenicity in vivo and may serve as a candidate for vaccine development against avian influenza A (H7N9) infection.


Asunto(s)
Antígenos Virales/inmunología , Pollos/inmunología , Virus de la Influenza A/inmunología , Ratones/inmunología , Vacunas de Partículas Similares a Virus/inmunología , Animales , Antígenos Virales/genética , Femenino , Virus de la Influenza A/genética , Ratones Endogámicos BALB C , Ingeniería de Proteínas , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Especificidad de la Especie , Vacunas de Partículas Similares a Virus/genética
20.
Circ Res ; 116(5): 876-83, 2015 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-25605650

RESUMEN

RATIONALE: Kawasaki disease (KD), an acute febrile vasculitis, is the most common cause of acquired heart disease in childhood; however, diagnosing KD can be difficult. OBJECTIVE: To identify unique proteomic biomarkers that can be used to facilitate earlier diagnosis of KD. METHODS AND RESULTS: We enrolled 214 children with fever and clinical features suggestive of KD. Of those, only 100 were diagnosed with KD. Their plasma samples were globally analyzed for cytokines, chemokines, and cell adhesion molecules using an unbiased, large-scale, quantitative protein array. This study was conducted in 3 stages: discovery, replication, and blinded validation. During the discovery phase (n [KD]=37; n [control]=20), the expression of interleukin-17F, sCD40L, E-selectin, CCL23 (myeloid progenitor inhibitory factor 1), and CXCL10 (IFN-γ-inducible protein 10 [IP-10]) were upregulated during the acute phase in patients with KD when compared with that in the controls. A notable increase was observed in the IP-10 levels (KD, 3037 ± 226.7 pg/mL; control, 672 ± 130.4 pg/mL; P=4.1 × 10(-11)). Receiver-operating characteristic analysis of the combined discovery and replication data (n [KD]=77; n [control]=77) showed that the IP-10 level had high area under the curve values (0.94 [95% confidence interval, 0.9055-0.9778]; sensitivity, 100%; and specificity, 77%). With 1318 pg/mL as the optimal cutoff, the blinded validation study confirmed that the IP-10 levels were a good predictor of KD. With intravenous immunoglobulin treatment, the IP-10 levels returned to normal. The downstream receptor of IP-10, CXCR3, was activated in the T cells of patients with acute KD. CONCLUSIONS: IP-10 may be used as a biomarker to facilitate KD diagnosis, and it may provide clues about the pathogenesis of KD.


Asunto(s)
Quimiocina CXCL10/sangre , Síndrome Mucocutáneo Linfonodular/sangre , Biomarcadores/sangre , Moléculas de Adhesión Celular/sangre , Quimiocina CXCL10/fisiología , Quimiocinas/sangre , Niño , Preescolar , Citocinas/sangre , Femenino , Fiebre/etiología , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Lactante , Recién Nacido , Inflamación , Masculino , Síndrome Mucocutáneo Linfonodular/diagnóstico , Síndrome Mucocutáneo Linfonodular/fisiopatología , Síndrome Mucocutáneo Linfonodular/terapia , Curva ROC , Receptores CXCR3/metabolismo , Método Simple Ciego , Linfocitos T/metabolismo
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