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1.
J Asthma Allergy ; 17: 167-179, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38497090

RESUMEN

Purpose: Increasing seafood consumption is associated with more frequent reports of food allergy. Little is known about seafood allergy (SFA) among adults in Vietnam. We investigated the characteristics of individuals with SFA and the risk factors for severe SFA. Patients and methods: A cross-sectional, web-based survey was conducted among individuals aged ≥ 18 years from universities in Ho Chi Minh City (Vietnam) between December 2021 and July 2022. The survey was based on a structured, validated questionnaire related to FA. Strict definitions of "convincing allergy" were used. Multivariate analysis was used to estimate the risk factors for severe SFA after adjusting for covariates. Data were analyzed using JASP (v.0.16.3) and SPSS (v.22.0). Results: Totally, 1038 out of 2137 (48.57%) individuals completed the questionnaire, of whom 285 (27.46%) had reported SFA. Convincing SFA accounted for 20.13% (209/1038) of the cases, with convincing shellfish allergy being more common than fish allergy. Participants with comorbid shellfish and fish allergy had higher prevalence of atopic dermatitis, peanut/nut allergy, other food allergy, and cutaneous and upper airway symptoms compared to participants with shellfish allergy (p < 0.05). The spectrum of reactive seafood was diverse and characterized by local species. The age of symptom onset was most commonly during late childhood and adolescence, with most reactions persisting into adulthood. A history of anaphylaxis, comorbid peanut, and tree nut allergy, and ≥3 allergens were associated with severe SFA. Conclusion: Features of causative, coexisting seafood allergy, and risk factors for severe SFA were demonstrated, which can provide a reference for future studies.

2.
Int J Surg Case Rep ; 109: 108518, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37517249

RESUMEN

INTRODUCTION AND IMPORTANCE: Congenital teratomas arising from the oropharynx, also known as epignathus, are exceedingly rare tumours occurring in 1:35,000-200,000 live births. Although histologically benign, these tumours are often difficult to diagnose antenatally and can cause life-threatening airway obstruction in the newborn. CASE PRESENTATION: We present a case of a full-term female infant presenting at birth with respiratory distress and stridor. Clinical examination and magnetic resonance imaging showed a large multilobulated nasopharyngeal mass causing severe airway compromise. The infant underwent excision biopsy with partial debulking of the tumour surrounding the airway, and was successfully extubated thereafter to room air. Histopathological examination confirmed the diagnosis of mature teratoma. CLINICAL DISCUSSION: The pathophysiology of epignathus is thought to be aberrant proliferation of pluripotent cells in the notochord during early embryogenesis. Antenatally, elevated maternal alpha-fetoprotein or polyhydramnios may be clue to diagnosis. The mainstay of treatment is airway clearance with surgical resection, which can be curative or at least minimizes the risk of malignancy. CONCLUSION: This case highlights the importance of early recognition and multidisciplinary management of the neonatal airway, in order to improve outcome.

3.
Health Care Manag Sci ; 25(2): 191-207, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34505969

RESUMEN

The Radiotherapy Scheduling Problem (RTSP) focuses on optimizing the planning of radiotherapy treatment sessions for cancer patients. In this paper, we propose a two-phase approach for the RTSP. In the first phase, radiotherapy sessions are assigned to specific linear accelerators (linacs) and days. The second phase then decides the sequence of patients on each day/linac and the specific appointment times. For the first phase, an Integer Linear Programming (IP) model is proposed and solved using CPLEX. For the second phase, a Mixed Integer Linear Programming (MIP) and a Constraint Programming (CP) model are proposed. The test data is generated based on real data from CHUM, a large cancer center in Montréal, Canada, with an average of 3,500 new patients and 40,000 radiotherapy treatments per year. The results show that in the second phase, CP is better at finding good solutions quickly while MIP is better at closing optimality gaps with more run time. Lastly, a simulation is conducted to evaluate the impact of different scheduling strategies on the outcome of the scheduling. Preliminary results show that batch scheduling reduces patients' waiting time and overdue time.


Asunto(s)
Citas y Horarios , Programación Lineal , Simulación por Computador , Humanos , Neoplasias , Aceleradores de Partículas , Radioterapia
4.
POCUS J ; 7(1): 171-178, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36896274

RESUMEN

Purpose: To determine medical student ability to accurately obtain and interpret POCUS exams of varying difficulty in the pediatric population after a short didactic and hands-on POCUS course. Methods: Five medical students were trained in four POCUS applications (bladder volume, long bone for fracture, limited cardiac for left ventricular function, & inferior vena cava collapsibility) and enrolled pediatric ED patients. Ultrasound-fellowship-trained emergency medicine physicians reviewed each scan for image quality and interpretation accuracy using the American College of Emergency Physicians' quality assessment scale. We report acceptable scan frequency and medical student vs. Ultrasound-fellowship-trained emergency medicine physician interpretation agreement with 95% confidence intervals (CI). Results: Ultrasound-fellowship-trained emergency medicine physicians graded 51/53 bladder volume scans as acceptable (96.2%; 95% CI 87.3-99.0%) and agreed with 50/53 bladder volume calculations (94.3%; 95% CI 88.1-100%). Ultrasound-fellowship-trained emergency medicine physicians graded 35/37 long bone scans as acceptable (94.6%; 95% CI 82.3-98.5%) and agreed with 32/37 medical student long bone scan interpretations (86.5%; 95% CI 72.0-94.1%). Ultrasound-fellowship-trained emergency medicine physicians graded 116/120 cardiac scans as acceptable (96.7%; 95% CI 91.7-98.7%) and agreed with 111/120 medical student left ventricular function interpretations (92.5%; 95% CI 86.4-96.0%). Ultrasound-fellowship-trained emergency medicine physicians graded 99/117 inferior vena cava scans as acceptable (84.6%; 95% CI 77.0-90.0%) and agreed with 101/117 medical student interpretations of inferior vena cava collapsibility (86.3%; 95% CI 78.9-91.4%). Conclusions: Medical students demonstrated satisfactory ability within a short period of time in a range of POCUS scans on pediatric patients after a novel curriculum. This supports the incorporation of a formal POCUS education into medical school curricula and suggests that novice POCUS learners can attain a measure of competency in multiple applications after a short training course.

5.
Angew Chem Int Ed Engl ; 59(19): 7456-7460, 2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-32052908

RESUMEN

We report a reaction platform for the synthesis of three different high-value specialty chemical building blocks starting from bio-ethanol, which might have an important impact in the implementation of biorefineries. First, oxidative dehydrogenation of ethanol to acetaldehyde generates an aldehyde-containing stream active for the production of C4 aldehydes via base-catalyzed aldol-condensation. Then, the resulting C4 adduct is selectively converted into crotonic acid via catalytic aerobic oxidation (62 % yield). Using a sequential epoxidation and hydrogenation of crotonic acid leads to 29 % yield of ß-hydroxy acid (3-hydroxybutanoic acid). By controlling the pH of the reaction media, it is possible to hydrolyze the oxirane moiety leading to 21 % yield of α,ß-dihydroxy acid (2,3-dihydroxybutanoic acid). Crotonic acid, 3-hydroxybutanoic acid, and 2,3-dihydroxybutanoic acid are archetypal specialty chemicals used in the synthesis of polyvinyl-co-unsaturated acids resins, pharmaceutics, and bio-degradable/ -compatible polymers, respectively.

7.
Cells ; 8(4)2019 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-30987218

RESUMEN

Knee osteoarthritis (OA) is one of the most prevalent disorders in elderly population. Among various therapeutic alternatives, we employed stromal vascular fraction (SVF), a heterogeneous cell population, to regenerate damaged knee cartilage. OA patients were classified on the basis of age, gender, body mass index (BMI), and x-ray-derived Kellgren-Lawrence (KL) grade. They were treated with SVF and followed-up for 24 months. Visual analogue scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index were used to determine treatment efficacy. Cartilage healing was assessed using the MRI-based Outerbridge score (OS) and evaluation of bone marrow edema (BME) lesions, while a placebo group was used as a control. Time- and KL-dependent changes were also monitored. We observed a decreasing trend in VAS score and WOMAC index in the SVF-treated group up to 24 months, as compared with the placebo group. Besides, a significant increase and decrease in Lysholm and OS, respectively, were observed in the treatment group. Compared with the values before treatment, the greatly reduced WOMAC scores of KL3 than KL2 groups at 24 months, indicate more improvement in the KL3 group. Highly decreased BME in the treated group was also noted. In conclusion, the SVF therapy is effective in the recovery of OA patients of KL3 grade in 24 months.


Asunto(s)
Osteoartritis de la Rodilla/terapia , Trasplante de Células Madre , Huesos/patología , Cartílago/lesiones , Cartílago/patología , Edema/patología , Femenino , Humanos , Inyecciones Intraarticulares , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico por imagen , Células del Estroma/trasplante , Resultado del Tratamiento , Escala Visual Analógica , Cicatrización de Heridas
8.
IEEE Trans Pattern Anal Mach Intell ; 40(12): 2883-2896, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29989962

RESUMEN

We consider the problem of estimating realistic contact forces during manipulation, backed with ground-truth measurements, using vision alone. Interaction forces are usually measured by mounting force transducers onto the manipulated objects or the hands. Those are costly, cumbersome, and alter the objects' physical properties and their perception by the human sense of touch. Our work establishes that interaction forces can be estimated in a cost-effective, reliable, non-intrusive way using vision. This is a complex and challenging problem. Indeed, in multi-contact, a given motion can generally be caused by an infinity of possible force distributions. To alleviate the limitations of traditional models based on inverse optimization, we collect and release the first large-scale dataset on manipulation kinodynamics as 3.2 hours of synchronized force and motion measurements under 193 object-grasp configurations. We learn a mapping between high-level kinematic features based on the equations of motion and the underlying manipulation forces using recurrent neural networks (RNN). The RNN predictions are consistently refined using physics-based optimization through second-order cone programming (SOCP). We show that our method can successfully capture interaction forces compatible with both the observations and the way humans intuitively manipulate objects, using a single RGB-D camera.

9.
Heliyon ; 4(12): e01039, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30603685

RESUMEN

Development of resistance to chemotherapy is a major obstacle in extending the survival of patients with cancer. Although originally defined as an immune checkpoint molecule, B7-H1 (also named as PD-L1 or CD274) was found to play a role in cancer chemoresistance; however, the underlying mechanism of action of B7-H1 in regulation of chemotherapy sensitivity remains unclear in cancer cells. Here we show that development of chemoresistance depends on an increased activation of ERK in cancer cells overexpressing B7-H1. Conversely, B7-H1 knockout (KO) by CRISPR/Cas9 renders human cancer cells susceptible to chemotherapy in a cell-context dependent manner through a reduced activation of p38 MAPK. B7-H1 was found to associate with the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs) and this association promoted or maintained the activation of ERK or p38 MAPK in cancer cells. Importantly, we found that targeting B7-H1 by anti-B7-H1 monoclonal antibody (H1A) increased the sensitivity of human triple negative breast cancer cells to cisplatin therapy in vivo. Our results suggest that targeting B7-H1 by an antibody capable of disrupting B7-H1 signals may be a new approach to sensitize cancer cells to chemotherapy.

10.
Acta Paediatr ; 106(5): 749-754, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28196284

RESUMEN

AIM: This study examined the heart rate variability characteristics associated with early-onset neonatal sepsis in a prospective, observational controlled study. METHODS: Eligible patients were full-term neonates hospitalised with clinical signs that suggested early-onset sepsis and a C-reactive protein of >10 mg/L. Sepsis was considered proven in cases of symptomatic septicaemia, meningitis, pneumonia or enterocolitis. Heart rate variability parameters (n = 16) were assessed from five-, 15- and 30-minute stationary sequences automatically selected from electrocardiographic recordings performed at admission and compared with a control group using the U-test with post hoc Benjamini-Yekutieli correction. Stationary sequences corresponded to the periods with the lowest changes of heart rate variability over time. RESULTS: A total of 40 full-term infants were enrolled, including 14 with proven sepsis. The mean duration of the cardiac cycle length was lower in the proven sepsis group than in the control group (n = 11), without other significant changes in heart rate variability parameters. These durations, measured in five-minute stationary periods, were 406 (367-433) ms in proven sepsis group versus 507 (463-522) ms in the control group (p < 0.05). CONCLUSION: Early-onset neonatal sepsis was associated with a high mean heart rate measured during automatically selected stationary periods.


Asunto(s)
Frecuencia Cardíaca , Sepsis Neonatal/fisiopatología , Estudios de Casos y Controles , Femenino , Humanos , Recién Nacido , Masculino , Estudios Prospectivos
11.
J Virol ; 91(3)2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-27852857

RESUMEN

Hepatitis C virus (HCV) is highly dependent on cellular factors for viral propagation. Using high-throughput next-generation sequencing, we analyzed the host transcriptomic changes and identified 30 candidate genes which were upregulated in cell culture-grown HCV (HCVcc)-infected cells. Of these candidates, we selected Rab32 for further investigation. Rab32 is a small GTPase that regulates a variety of intracellular membrane-trafficking events in various cell types. In this study, we demonstrated that both mRNA and protein levels of Rab32 were increased in HCV-infected cells. Furthermore, we showed that HCV infection converted the predominantly expressed GTP-bound Rab32 to GDP-bound Rab32, contributing to the aggregation of Rab32 and thus making it less sensitive to cellular degradation machinery. In addition, GDP-bound Rab32 selectively interacted with HCV core protein and deposited core protein into the endoplasmic reticulum (ER)-associated Rab32-derived aggregated structures in the perinuclear region, which were likely to be viral assembly sites. Using RNA interference technology, we demonstrated that Rab32 was required for the assembly step but not for other stages of the HCV life cycle. Taken together, these data suggest that HCV may modulate Rab32 activity to facilitate virion assembly. IMPORTANCE: Rab32, a member of the Ras superfamily of small GTPases, regulates various intracellular membrane-trafficking events in many cell types. In this study, we showed that HCV infection concomitantly increased Rab32 expression at the transcriptional level and altered the balance between GDP- and GTP-bound Rab32 toward production of Rab32-GDP. GDP-bound Rab32 selectively interacted with HCV core protein and enriched core in the ER-associated Rab32-derived aggregated structures that were probably necessary for viral assembly. Indeed, we showed that Rab32 was specifically required for the assembly of HCV. Collectively, our study identifies that Rab32 is a novel host factor essential for HCV particle assembly.


Asunto(s)
Hepacivirus/fisiología , Hepatitis C/metabolismo , Hepatitis C/virología , Agregado de Proteínas , Ensamble de Virus , Proteínas de Unión al GTP rab/metabolismo , Línea Celular , Expresión Génica , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Hepatitis C/genética , Interacciones Huésped-Patógeno , Humanos , Mutación , Regiones Promotoras Genéticas , Unión Proteica , Proteínas del Núcleo Viral/genética , Proteínas del Núcleo Viral/metabolismo , Replicación Viral , Proteínas de Unión al GTP rab/genética
12.
Oncotarget ; 7(43): 69136-69148, 2016 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-27655701

RESUMEN

OBJECTIVE: Chronic Helicobacter pylori (H. pylori) infection promotes non-cardia gastric cancer. Some mouse models suggest that bone marrow derived cells (BMDC) contribute to Helicobacter-associated gastric carcinogenesis. We determined whether this increased susceptibility to Helicobacter-induced gastric carcinogenesis of p27-deficient mice is dependent upon their p27-null BMDC or their p27-null gastric epithelial cells. DESIGN: Female mice (recipients) were irradiated and transplanted with BMDC from male donors. Wild type (WT) mice in group 1 (control) received BMDC from male GFP-transgenic mice. Female WT and p27 KO mice were engrafted with male p27KO mice BMDC (Group 2) or GFP-transgenic WT BMDC (Group 3). Recipients were infected with H. pylori SS1 for one year. RESULTS: Mice lacking p27 in either the BM pool or gastric epithelium developed significantly more advanced gastric pathology, including high-grade dysplasia. Co-staining of donor BMDC in dysplastic gastric glands was confirmed by immunofluorescence. Gastric expression of IL-1 beta protein was reduced in groups 2 and 3 (p < 0.05 vs control) whereas expression of IFN-γ and chemokines MIP-1 beta, MIG, IP-10 and RANTES in group 2 were significantly higher than group 3. CONCLUSIONS: Both bone marrow-derived and gastric epithelial cells contribute to the increased gastric cancer susceptibility of p27-deficient H. pylori-infected mice.


Asunto(s)
Células de la Médula Ósea/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/deficiencia , Infecciones por Helicobacter/metabolismo , Neoplasias Gástricas/metabolismo , Animales , Células de la Médula Ósea/microbiología , Trasplante de Médula Ósea/métodos , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Citocinas/metabolismo , Células Epiteliales/metabolismo , Células Epiteliales/microbiología , Células Epiteliales/patología , Femenino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/fisiología , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Mosaicismo , Neoplasias Gástricas/microbiología
13.
J Biol Chem ; 291(43): 22607-22617, 2016 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-27551040

RESUMEN

The propagation of hepatitis C virus (HCV) is highly dependent on host cellular factors. To identify the cellular factors involved in HCV propagation, we have previously performed protein microarray assays using the HCV nonstructural 5A (NS5A) protein as a probe. Of ∼9,000 host proteins immobilized in a microarray, ∼90 cellular proteins were identified as HCV NS5A interacting partners. Of these candidates, we selected Abelson interactor 1 (Abi1) for further characterization. Binding of HCV NS5A to Abi1 was verified by both in vitro pulldown and coimmunoprecipitation assays. HCV NS5A interacted with Abi1 through regions I + II of Abi1 and domain I of NS5A. We further demonstrated that Abi1 colocalized with the HCV NS5A protein in the cytoplasm. We showed that NS5A inhibited epidermal growth factor-mediated ERK and Egr1 activations and this inhibitory activity of NS5A was nullified in Abi1-knockdown cells. Moreover, silencing of Abi1 expression impaired HCV replication, whereas overexpression of Abi1 promoted HCV propagation. Collectively, these data indicate that HCV exploits host Abi1 protein via NS5A to modulate MEK/ERK signaling pathway for its own propagation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas del Citoesqueleto/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Hepacivirus/fisiología , Sistema de Señalización de MAP Quinasas , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/fisiología , Proteínas Adaptadoras Transductoras de Señales/genética , Línea Celular , Proteínas del Citoesqueleto/genética , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Factor de Crecimiento Epidérmico/genética , Silenciador del Gen , Humanos , Unión Proteica , Proteínas no Estructurales Virales/genética
14.
J Virol ; 90(16): 7231-7247, 2016 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-27252525

RESUMEN

UNLABELLED: Hepatitis C virus (HCV) infection often causes chronic hepatitis, liver cirrhosis, and ultimately hepatocellular carcinoma. However, the mechanisms underlying HCV-induced liver pathogenesis are still not fully understood. By transcriptome sequencing (RNA-Seq) analysis, we recently identified host genes that were significantly differentially expressed in cell culture-grown HCV (HCVcc)-infected cells. Of these, tribbles homolog 3 (TRIB3) was selected for further characterization. TRIB3 was initially identified as a binding partner of protein kinase B (also known as Akt). TRIB3 blocks the phosphorylation of Akt and induces apoptosis under endoplasmic reticulum (ER) stress conditions. HCV has been shown to enhance Akt phosphorylation for its own propagation. In the present study, we demonstrated that both mRNA and protein levels of TRIB3 were increased in the context of HCV replication. We further showed that promoter activity of TRIB3 was increased by HCV-induced ER stress. Silencing of TRIB3 resulted in increased RNA and protein levels of HCV, whereas overexpression of TRIB3 decreased HCV replication. By employing an HCV pseudoparticle entry assay, we further showed that TRIB3 was a negative host factor involved in HCV entry. Both in vitro binding and immunoprecipitation assays demonstrated that HCV NS3 specifically interacted with TRIB3. Consequently, the association of TRIB3 and Akt was disrupted by HCV NS3, and thus, TRIB3-Akt signaling was impaired in HCV-infected cells. Moreover, HCV modulated TRIB3 to promote extracellular signal-regulated kinase (ERK) phosphorylation, activator protein 1 (AP-1) activity, and cell migration. Collectively, these data indicate that HCV exploits the TRIB3-Akt signaling pathway to promote persistent viral infection and may contribute to HCV-mediated pathogenesis. IMPORTANCE: TRIB3 is a pseudokinase protein that acts as an adaptor in signaling pathways for important cellular processes. So far, the functional involvement of TRIB3 in virus-infected cells has not yet been demonstrated. We showed that both mRNA and protein expression levels of TRIB3 were increased in the context of HCV RNA replication. Gene silencing of TRIB3 increased HCV RNA and protein levels, and thus, overexpression of TRIB3 decreased HCV replication. TRIB3 is known to promote apoptosis by negatively regulating the Akt signaling pathway under ER stress conditions. Most importantly, we demonstrated that the TRIB3-Akt signaling pathway was disrupted by NS3 in HCV-infected cells. These data provide evidence that HCV modulates the TRIB3-Akt signaling pathway to establish persistent viral infection.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Hepacivirus/fisiología , Hepatitis C/virología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Represoras/metabolismo , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/fisiología , Western Blotting , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/genética , Células Cultivadas , Estrés del Retículo Endoplásmico/fisiología , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Técnica del Anticuerpo Fluorescente , Células HEK293 , Hepatitis C/genética , Hepatitis C/metabolismo , Hepatocitos/citología , Hepatocitos/metabolismo , Hepatocitos/virología , Interacciones Huésped-Patógeno , Humanos , Inmunoprecipitación , Proteínas Quinasas Activadas por Mitógenos/genética , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , ARN Mensajero/genética , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Represoras/antagonistas & inhibidores , Proteínas Represoras/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Proteínas no Estructurales Virales/genética , Virión/fisiología , Internalización del Virus
15.
ChemSusChem ; 9(7): 736-48, 2016 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-26938793

RESUMEN

A new type of catalyst has been designed to adjust the basicity and level of molecular confinement of KNaX faujasites by controlled incorporation of Mg through ion exchange and precipitation of extraframework MgO clusters at varying loadings. The catalytic performance of these catalysts was compared in the conversion of C2 and C4 aldehydes to value-added products. The product distribution depends on both the level of acetaldehyde conversion and the fraction of magnesium as extraframework species. These species form rather uniform and highly dispersed nanostructures that resemble nanopetals. Specifically, the sample containing Mg only in the form of exchangeable Mg(2+) ions has much lower activity than those in which a significant fraction of Mg exists as extraframework MgO. Both the (C6+C8)/C4 and C8/C6 ratios increase with additional extraframework Mg at high acetaldehyde conversion levels. These differences in product distribution can be attributed to 1) higher basicity density on the samples with extraframework species, and 2) enhanced confinement inside the zeolite cages in the presence of these species. Additionally, the formation of linear or aromatic C8 aldehyde compounds depends on the position on the crotonaldehyde molecule from which abstraction of a proton occurs. In addition, catalysts with different confinement effects result in different C8 products.


Asunto(s)
Óxido de Magnesio/química , Zeolitas/química , Catálisis , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Rastreo , Difracción de Rayos X
16.
Cell Host Microbe ; 16(4): 504-16, 2014 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-25263220

RESUMEN

Our intestinal microbiota harbors a diverse microbial community, often containing opportunistic bacteria with virulence potential. However, mutualistic host-microbial interactions prevent disease by opportunistic pathogens through poorly understood mechanisms. We show that the epithelial interleukin-22 receptor IL-22RA1 protects against lethal Citrobacter rodentium infection and chemical-induced colitis by promoting colonization resistance against an intestinal opportunistic bacterium, Enterococcus faecalis. Susceptibility of Il22ra1(-/-) mice to C. rodentium was associated with preferential expansion and epithelial translocation of pathogenic E. faecalis during severe microbial dysbiosis and was ameloriated with antibiotics active against E. faecalis. RNA sequencing analyses of primary colonic organoids showed that IL-22RA1 signaling promotes intestinal fucosylation via induction of the fucosyltransferase Fut2. Additionally, administration of fucosylated oligosaccharides to C. rodentium-challenged Il22ra1(-/-) mice attenuated infection and promoted E. faecalis colonization resistance by restoring the diversity of anaerobic commensal symbionts. These results support a model whereby IL-22RA1 enhances host-microbiota mutualism to limit detrimental overcolonization by opportunistic pathogens.


Asunto(s)
Citrobacter rodentium/inmunología , Colitis/prevención & control , Enterococcus faecalis/inmunología , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Interacciones Microbianas , Receptores de Interleucina/metabolismo , Animales , Traslocación Bacteriana , Citrobacter rodentium/fisiología , Colitis/inducido químicamente , Susceptibilidad a Enfermedades , Disbiosis , Enterococcus faecalis/fisiología , Fucosiltransferasas/metabolismo , Ratones , Ratones Noqueados , Receptores de Interleucina/genética , Transducción de Señal , Galactósido 2-alfa-L-Fucosiltransferasa
17.
Rev Sci Instrum ; 85(5): 054903, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24880399

RESUMEN

Modulated photothermal radiometry is a non-destructive and contactless technique for the characterization of materials. It has two major advantages: a good signal-to-noise ratio through a synchronous detection and a low dependence on the heating power and the optical properties of the sample surface. This paper presents a new method for characterizing the thermal diffusivity of a material when the phase shift between a modulated laser power signal and the thermal signal of a plate sample is known at different frequencies. The method is based on a three-dimensional analytical model which is used to determine the temperature amplitude and the phase in the laser heating of the plate. A new simple formula was developed through multi-parametric analysis to determine the thermal diffusivity of the plate with knowledge of the frequency at the minimum phase shift, the laser beam radius r0 and the sample thickness L. This method was developed to control the variation of the thermal diffusivity of nuclear components and it was first applied to determine the thermal diffusivity of different metals: 304 L stainless steel, nickel, titanium, tungsten, molybdenum, zinc, and iron. The experimental results were obtained with 5%-10% accuracy and corresponded well with the reference values. The present paper also demonstrates the limit of application of this method for plate with thickness r0/100 ≤ L ≤ r0/2. The technique is deemed interesting for the characterization of barely accessible components that require a contactless measurement.

18.
Curr Opin Microbiol ; 17: 67-74, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24581695

RESUMEN

Infection of the gastrointestinal tract is commonly linked to pathological imbalances of the resident microbiota, termed dysbiosis. In recent years, advanced high-throughput genomic approaches have allowed us to examine the microbiota in an unprecedented manner, revealing novel biological insights about infection-associated dysbiosis at the community and individual species levels. A dysbiotic microbiota is typically reduced in taxonomic diversity and metabolic function, and can harbour pathobionts that exacerbate intestinal inflammation or manifest systemic disease. Dysbiosis can also promote pathogen genome evolution, while allowing the pathogens to persist at high density and transmit to new hosts. A deeper understanding of bacterial pathogenicity in the context of the intestinal microbiota should unveil new approaches for developing diagnostics and therapies for enteropathogens.


Asunto(s)
Infecciones Bacterianas , Disbiosis , Enfermedades Intestinales , Microbiota , Animales , Humanos , Ratones , Modelos Biológicos
19.
J Food Prot ; 72(4): 810-7, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19435231

RESUMEN

Tetrodotoxin is a neurotoxin that occurs in select species of the family Tetraodontidae (puffer fish). It causes paralysis and potentially death if ingested in sufficient quantities. In 2007, two individuals developed symptoms consistent with tetrodotoxin poisoning after ingesting home-cooked puffer fish purchased in Chicago. Both the Chicago retailer and the California supplier denied having sold or imported puffer fish but claimed the product was monkfish. However, genetic analysis and visual inspection determined that the ingested fish and others from the implicated lot retrieved from the supplier belonged to the family Tetraodontidae. Tetrodotoxin was detected at high levels in both remnants of the ingested meal and fish retrieved from the implicated lot. The investigation led to a voluntary recall of monkfish distributed by the supplier in three states and placement of the supplier on the U.S. Food and Drug Administration's Import Alert for species misbranding. This case of tetrodotoxin poisoning highlights the need for continued stringent regulation of puffer fish importation by the U.S. Food and Drug Administration, education of the public regarding the dangers of puffer fish consumption, and raising awareness among medical providers of the diagnosis and management of foodborne toxin ingestions and the need for reporting to public health agencies.


Asunto(s)
Enfermedades Transmitidas por los Alimentos , Administración en Salud Pública , Tetraodontiformes , Tetrodotoxina/envenenamiento , Animales , Niño , Femenino , Peces Venenosos , Contaminación de Alimentos , Etiquetado de Alimentos , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Tetraodontiformes/genética
20.
J Adolesc ; 28(1): 127-46, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15683639

RESUMEN

Quality of life (QOL) of adolescents has been scarcely documented in a general population sample. The study was aimed at translating and adapting the Adolescent Duke Health Profile to Vietnamese, validating the questionnaire, determining reference value, and identifying determinants of poor QOL. Following a cross-cultural methodology, the Adolescent Duke Health Profile (ADHP) had content adapted to Vietnamese by alteration of 2 out of 17 items. Test-retest validity was checked in 408 adolescents. Construct validity and internal consistency were assessed in a 1408 probability sample of adolescents in Vietnam, and determinants were analysed by multiple linear regression. The ADHP showed satisfactory internal consistency (Cronbach's alpha=0.87-0.92) and satisfactory construct validity in relation with drug abuse or not, or with parent situation living in couple or alone. Test-retest reliability was acceptable (ICC=0.7-0.8) and major determinants were age, sex, education, chronic disease, alcohol and drug use. This works provide a validated, simple health related QOL scale suited to adolescent population with reference values. Taking into account determinants identified will help program prevention and intervention health policy and to evaluate the effect of these actions.


Asunto(s)
Calidad de Vida , Adolescente , Niño , Comparación Transcultural , Femenino , Estado de Salud , Humanos , Masculino , Psicometría , Reproducibilidad de los Resultados , Asunción de Riesgos , Encuestas y Cuestionarios , Vietnam
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