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1.
Nature ; 611(7937): 794-800, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36323785

RESUMEN

Protective immunity relies on the interplay of innate and adaptive immune cells with complementary and redundant functions. Innate lymphoid cells (ILCs) have recently emerged as tissue-resident, innate mirror images of the T cell system, with which they share lineage-specifying transcription factors and effector machinery1. Located at barrier surfaces, ILCs are among the first responders against invading pathogens and thus could potentially determine the outcome of the immune response2. However, so far it has not been possible to dissect the unique contributions of ILCs to protective immunity owing to limitations in specific targeting of ILC subsets. Thus, all of the available data have been generated either in mice lacking the adaptive immune system or with tools that also affect other immune cell subsets. In addition, it has been proposed that ILCs might be dispensable for a proper immune response because other immune cells could compensate for their absence3-7. Here we report the generation of a mouse model based on the neuromedin U receptor 1 (Nmur1) promoter as a driver for simultaneous expression of Cre recombinase and green fluorescent protein, which enables gene targeting in group 2 ILCs (ILC2s) without affecting other innate and adaptive immune cells. Using Cre-mediated gene deletion of Id2 and Gata3 in Nmur1-expressing cells, we generated mice with a selective and specific deficiency in ILC2s. ILC2-deficient mice have decreased eosinophil counts at steady state and are unable to recruit eosinophils to the airways in models of allergic asthma. Further, ILC2-deficient mice do not mount an appropriate immune and epithelial type 2 response, resulting in a profound defect in worm expulsion and a non-protective type 3 immune response. In total, our data establish non-redundant functions for ILC2s in the presence of adaptive immune cells at steady state and during disease and argue for a multilayered organization of the immune system on the basis of a spatiotemporal division of labour.


Asunto(s)
Sistema Inmunológico , Inmunidad Innata , Linfocitos , Animales , Ratones , Asma/genética , Asma/inmunología , Asma/patología , Modelos Animales de Enfermedad , Eosinófilos/patología , Inmunidad Innata/inmunología , Linfocitos/clasificación , Linfocitos/inmunología , Proteínas Fluorescentes Verdes , Sistema Inmunológico/citología , Sistema Inmunológico/inmunología , Sistema Inmunológico/patología
2.
Nature ; 586(7830): 509-515, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32967005

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the aetiological agent of coronavirus disease 2019 (COVID-19), an emerging respiratory infection caused by the introduction of a novel coronavirus into humans late in 2019 (first detected in Hubei province, China). As of 18 September 2020, SARS-CoV-2 has spread to 215 countries, has infected more than 30 million people and has caused more than 950,000 deaths. As humans do not have pre-existing immunity to SARS-CoV-2, there is an urgent need to develop therapeutic agents and vaccines to mitigate the current pandemic and to prevent the re-emergence of COVID-19. In February 2020, the World Health Organization (WHO) assembled an international panel to develop animal models for COVID-19 to accelerate the testing of vaccines and therapeutic agents. Here we summarize the findings to date and provides relevant information for preclinical testing of vaccine candidates and therapeutic agents for COVID-19.


Asunto(s)
Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/prevención & control , Modelos Animales de Enfermedad , Pandemias/prevención & control , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/prevención & control , Animales , Betacoronavirus/efectos de los fármacos , Betacoronavirus/inmunología , COVID-19 , Vacunas contra la COVID-19 , Infecciones por Coronavirus/inmunología , Hurones/virología , Humanos , Mesocricetus/virología , Ratones , Neumonía Viral/inmunología , Primates/virología , SARS-CoV-2 , Vacunas Virales/inmunología
3.
Mol Biol Evol ; 38(6): 2396-2412, 2021 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-33533884

RESUMEN

The cell cycle is a fundamental process that has been extensively studied in bacteria. However, many of its components and their interactions with machineries involved in other cellular processes are poorly understood. Furthermore, most knowledge relies on the study of a few models, but the real diversity of the cell division apparatus and its evolution are largely unknown. Here, we present a massive in-silico analysis of cell division and associated processes in around 1,000 genomes of the Firmicutes, a major bacterial phylum encompassing models (i.e. Bacillus subtilis, Streptococcus pneumoniae, and Staphylococcus aureus), as well as many important pathogens. We analyzed over 160 proteins by using an original approach combining phylogenetic reconciliation, phylogenetic profiles, and gene cluster survey. Our results reveal the presence of substantial differences among clades and pinpoints a number of evolutionary hotspots. In particular, the emergence of Bacilli coincides with an expansion of the gene repertoires involved in cell wall synthesis and remodeling. We also highlight major genomic rearrangements at the emergence of Streptococcaceae. We establish a functional network in Firmicutes that allows identifying new functional links inside one same process such as between FtsW (peptidoglycan polymerase) and a previously undescribed Penicilin-Binding Protein or between different processes, such as replication and cell wall synthesis. Finally, we identify new candidates involved in sporulation and cell wall synthesis. Our results provide a previously undescribed view on the diversity of the bacterial cell cycle, testable hypotheses for further experimental studies, and a methodological framework for the analysis of any other biological system.


Asunto(s)
Evolución Biológica , División Celular/genética , Firmicutes/genética , Familia de Multigenes , Simulación por Computador , Sintenía
4.
Nature ; 536(7617): 474-8, 2016 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-27355570

RESUMEN

Zika virus (ZIKV) is a flavivirus that is responsible for the current epidemic in Brazil and the Americas. ZIKV has been causally associated with fetal microcephaly, intrauterine growth restriction, and other birth defects in both humans and mice. The rapid development of a safe and effective ZIKV vaccine is a global health priority, but very little is currently known about ZIKV immunology and mechanisms of immune protection. Here we show that a single immunization with a plasmid DNA vaccine or a purified inactivated virus vaccine provides complete protection in susceptible mice against challenge with a strain of ZIKV involved in the outbreak in northeast Brazil. This ZIKV strain has recently been shown to cross the placenta and to induce fetal microcephaly and other congenital malformations in mice. We produced DNA vaccines expressing ZIKV pre-membrane and envelope (prM-Env), as well as a series of deletion mutants. The prM-Env DNA vaccine, but not the deletion mutants, afforded complete protection against ZIKV, as measured by absence of detectable viraemia following challenge, and protective efficacy correlated with Env-specific antibody titers. Adoptive transfer of purified IgG from vaccinated mice conferred passive protection, and depletion of CD4 and CD8 T lymphocytes in vaccinated mice did not abrogate this protection. These data demonstrate that protection against ZIKV challenge can be achieved by single-shot subunit and inactivated virus vaccines in mice and that Env-specific antibody titers represent key immunologic correlates of protection. Our findings suggest that the development of a ZIKV vaccine for humans is likely to be achievable.


Asunto(s)
Vacunas Virales/inmunología , Infección por el Virus Zika/prevención & control , Infección por el Virus Zika/virología , Virus Zika/inmunología , Traslado Adoptivo , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Especificidad de Anticuerpos , Brasil , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Femenino , Eliminación de Gen , Humanos , Inmunoglobulina G/inmunología , Inmunoglobulina G/aislamiento & purificación , Ratones , Microcefalia/complicaciones , Microcefalia/virología , Vacunas de ADN/química , Vacunas de ADN/genética , Vacunas de ADN/inmunología , Vacunas de Productos Inactivados/química , Vacunas de Productos Inactivados/genética , Vacunas de Productos Inactivados/inmunología , Vacunas de Subunidad/química , Vacunas de Subunidad/genética , Vacunas de Subunidad/inmunología , Proteínas del Envoltorio Viral/química , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/inmunología , Vacunas Virales/química , Vacunas Virales/genética , Virus Zika/química , Virus Zika/genética , Infección por el Virus Zika/complicaciones , Infección por el Virus Zika/inmunología
5.
Nature ; 534(7606): 267-71, 2016 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-27279226

RESUMEN

Zika virus (ZIKV) is an arbovirus belonging to the genus Flavivirus (family Flaviviridae) and was first described in 1947 in Uganda following blood analyses of sentinel Rhesus monkeys. Until the twentieth century, the African and Asian lineages of the virus did not cause meaningful infections in humans. However, in 2007, vectored by Aedes aegypti mosquitoes, ZIKV caused the first noteworthy epidemic on the Yap Island in Micronesia. Patients experienced fever, skin rash, arthralgia and conjunctivitis. From 2013 to 2015, the Asian lineage of the virus caused further massive outbreaks in New Caledonia and French Polynesia. In 2013, ZIKV reached Brazil, later spreading to other countries in South and Central America. In Brazil, the virus has been linked to congenital malformations, including microcephaly and other severe neurological diseases, such as Guillain-Barré syndrome. Despite clinical evidence, direct experimental proof showing that the Brazilian ZIKV (ZIKV(BR)) strain causes birth defects remains absent. Here we demonstrate that ZIKV(BR) infects fetuses, causing intrauterine growth restriction, including signs of microcephaly, in mice. Moreover, the virus infects human cortical progenitor cells, leading to an increase in cell death. We also report that the infection of human brain organoids results in a reduction of proliferative zones and disrupted cortical layers. These results indicate that ZIKV(BR) crosses the placenta and causes microcephaly by targeting cortical progenitor cells, inducing cell death by apoptosis and autophagy, and impairing neurodevelopment. Our data reinforce the growing body of evidence linking the ZIKV(BR) outbreak to the alarming number of cases of congenital brain malformations. Our model can be used to determine the efficiency of therapeutic approaches to counteracting the harmful impact of ZIKV(BR) in human neurodevelopment.


Asunto(s)
Modelos Animales de Enfermedad , Microcefalia/virología , Virus Zika/patogenicidad , Animales , Apoptosis , Autofagia , Encéfalo/patología , Encéfalo/virología , Brasil/epidemiología , Proliferación Celular , Femenino , Retardo del Crecimiento Fetal/patología , Retardo del Crecimiento Fetal/virología , Feto/virología , Ratones , Microcefalia/epidemiología , Microcefalia/etiología , Microcefalia/patología , Células-Madre Neurales/patología , Células-Madre Neurales/virología , Organoides/patología , Organoides/virología , Placenta/virología , Embarazo , Infección por el Virus Zika/complicaciones , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/patología , Infección por el Virus Zika/virología
6.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36142200

RESUMEN

Viral infections have always been a serious burden to public health, increasing morbidity and mortality rates worldwide. Zika virus (ZIKV) is a flavivirus transmitted by the Aedes aegypti vector and the causative agent of severe fetal neuropathogenesis and microcephaly. The virus crosses the placenta and reaches the fetal brain, mainly causing the death of neuronal precursor cells (NPCs), glial inflammation, and subsequent tissue damage. Genetic differences, mainly related to the antiviral immune response and cell death pathways greatly influence the susceptibility to infection. These components are modulated by many factors, including microRNAs (miRNAs). MiRNAs are small noncoding RNAs that regulate post-transcriptionally the overall gene expression, including genes for the neurodevelopment and the formation of neural circuits. In this context, we investigated the pathways and target genes of miRNAs modulated in NPCs infected with ZIKV. We observed downregulation of miR-302b, miR-302c and miR-194, whereas miR-30c was upregulated in ZIKV infected human NPCs in vitro. The analysis of a public dataset of ZIKV-infected human NPCs evidenced 262 upregulated and 3 downregulated genes, of which 142 were the target of the aforementioned miRNAs. Further, we confirmed a correlation between miRNA and target genes affecting pathways related to antiviral immune response, cell death and immune cells chemotaxis, all of which could contribute to the establishment of microcephaly and brain lesions. Here, we suggest that miRNAs target gene expression in infected NPCs, directly contributing to the pathogenesis of fetal microcephaly.


Asunto(s)
MicroARNs , Microcefalia , Malformaciones del Sistema Nervioso , Infección por el Virus Zika , Virus Zika , Animales , Antivirales , Muerte Celular/genética , Quimiotaxis , Femenino , Humanos , Inmunidad , MicroARNs/genética , Microcefalia/genética , Mosquitos Vectores , Embarazo , Virus Zika/fisiología
7.
Br J Haematol ; 189(2): 351-362, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31837008

RESUMEN

We investigated the long-term outcome, the incidence of second neoplasms (SN) and the rate of late adverse effects (LAE) in children with central nervous system (CNS) negative medium/high-risk de novo acute lymphoblastic leukaemia (ALL), in first complete remission (CR1) at end of late intensification, randomized to receive no cranial radiotherapy (No CRT, n = 92) versus CRT (standard arm, n = 84) in the non-inferiority EORTC 58832 study (1983-1989). Median follow-up was 20 years (range 4-32 years). The 25-year disease-free survival rate (±SE) was 67·4 ± 4·9% without CRT and 70·2 ± 5·0% with CRT. The 25-year incidence of isolated (6·5 ± 2·6% vs. 4·8 ± 2·3%) and any CNS relapse {8·7 ± 2·9% vs. 11·9 ± 3·5%; hazard ratio (HR) 0·71 [95% confidence interval (CI) 0·28-1·79]; test of non-inferiority: P = 0·01} was not increased without CRT. The 25-year SN incidence in CR1 was 7·9 ± 4·6% vs. 11·0 ± 4·2%. The 25-year event-free and overall survival rates were quite similar in both arms [59·5 ± 6·3% vs. 60·5 ± 5·9%, HR 0·94 (95% CI 0·57-1·52), and 78·1 ± 4·3% vs. 78·5 ± 4·5%, HR 1·00 (95% CI 0·53-1·88)]. Omission of CRT was associated with dramatic decrease in CNS and endocrine LAE rates. In conclusion, our data suggest that, with proper systemic and intrathecal CNS prophylaxis, CRT could totally be omitted in CR1 without jeopardizing survival, while decreasing LAE in childhood ALL.


Asunto(s)
Irradiación Craneana/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Resultado del Tratamiento , Adulto Joven
8.
Blood ; 132(7): 750-754, 2018 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-29760162

RESUMEN

Outcomes remain poor for refractory severe aplastic anemia (SAA) patients. Alternative donor transplantation may be considered, but results from previous studies are not encouraging. We conducted a prospective nationwide phase 2 study to assess unrelated cord blood (CB) transplantation (CBT) efficacy and safety in refractory SAA patients (Aplastic Anemia and Cord Blood Transplantation protocol). To demonstrate a significant difference in 1-year survival from 20% (null hypothesis) to 50% (alternative hypothesis), we needed to include 25 transplanted patients and therefore included 26 (median age, 16 years). Eligibility criteria required 1 or 2 unrelated CB units, containing separately or together >4 × 107 frozen nucleated cells (NCs) per kilogram of recipient body weight. Conditioning regimen comprised fludarabine (FLU), cyclophosphamide (CY), antithymocyte globulin (ATG), and 2-Gy total body irradiation (TBI). With a median follow-up of 38.8 months, engraftment occurred in 23 patients (88%); cumulative incidences of grade II-IV acute and chronic graft-versus-host disease were 45.8% and 36%, respectively. Twenty-three patients were alive at 1 year, with an 88.5% overall survival (OS) rate, differing significantly from the expected 20% (P < .0001; 84% OS at 2 years). CBT with units containing ≥4 × 107 frozen NCs per kilogram is therefore a valuable curative option for young adults with refractory SAA and no available matched unrelated donors. This trial was registered at www.clinicaltrials.gov as #NCT01343953.


Asunto(s)
Anemia Aplásica/mortalidad , Anemia Aplásica/terapia , Trasplante de Células Madre de Sangre del Cordón Umbilical , Acondicionamiento Pretrasplante , Donante no Emparentado , Enfermedad Aguda , Adolescente , Adulto , Alanina/administración & dosificación , Alanina/análogos & derivados , Aloinjertos , Suero Antilinfocítico/administración & dosificación , Niño , Supervivencia sin Enfermedad , Femenino , Enfermedad Injerto contra Huésped/mortalidad , Enfermedad Injerto contra Huésped/prevención & control , Humanos , Masculino , Tasa de Supervivencia , Irradiación Corporal Total
9.
Cytokine ; 133: 155144, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32559663

RESUMEN

INTRODUCTION: Adipose tissue secretes various bioactive peptides/proteins, immune molecules and inflammatory mediators which are known as adipokines or adipocytokines. Adipokines play important roles in the maintenance of energy homeostasis, appetite, glucose and lipid metabolism, insulin sensitivity, angiogenesis, immunity and inflammation. Enormous number of studies from all over the world proved that adipocytokines are involved in the pathogenesis of diseases affecting nearly all body systems, which raises the question whether we can always blame adipocytokines as the triggering factor of every disease that may hit the body. OBJECTIVE: Our review targeted the role played by adipocytokines in the pathogenesis of different diseases affecting different body systems including diabetes mellitus, kidney diseases, gynecological diseases, rheumatologic disorders, cancers, Alzheimer's, depression, muscle disorders, liver diseases, cardiovascular and lung diseases. METHODOLOGY: We cited more than 33 recent literature reviews that discussed the role played by adipocytokines in the pathogenesis of different diseases affecting different body systems. CONCLUSION: More evidence is being discovered to date about the role played by adipocytokines in more diseases and extra research is needed to explore hidden roles played by adipokine imbalance on disease pathogenesis.


Asunto(s)
Adipoquinas/metabolismo , Tejido Adiposo/metabolismo , Animales , Humanos , Inmunidad/fisiología , Inflamación/metabolismo , Mediadores de Inflamación/metabolismo
10.
J Anim Ecol ; 89(12): 2852-2862, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33111342

RESUMEN

Many species show territoriality, in which territory owners have exclusive or priority use of a region. In humans, tolerance of others within our space also depends greatly on our social relationships with them. This has been hypothesized as one potential driver of the evolution of long-term, inter-group relationships, through enabling shared access of resources and easing disputes over space. However, extremely little is known about the importance of social relationships between neighbouring groups in non-humans for how space is used and shared. Using 16 years of data on the simultaneous movement and interaction patterns of 17 mountain gorilla groups, we investigated how the occurrence of aggressive and affiliative behaviour during inter-group encounters was influenced by both their social and spatial context. We found evidence of territorial defence, with rates of aggression increasing towards the centre of home ranges. Groups which had previously split from each other showed higher levels of affiliation during encounters with each other and experienced lower levels of aggression when within the other's peripheral home range. However, encounters within core areas of the home range consistently elicited higher aggression, regardless of the groups' history. Our findings indicate that not only are the social relationships between groups retained after they split from one another but also that these relationships enable groups to access certain areas with a reduced risk of aggression. This suggests that reduced aggression when accessing areas within neighbours' home ranges may be an advantage for the maintenance of inter-group relationships and a potential driver in the evolution of long-term, post-dispersal relationships and complex multi-level societies.


Asunto(s)
Gorilla gorilla , Territorialidad , Agresión , Animales , Fenómenos de Retorno al Lugar Habitual
11.
Mol Biol Rep ; 47(2): 1143-1151, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31820316

RESUMEN

Renal cell carcinoma (RCC) is a highly deadly urological tumor due to its high metastatic incidence and its notorious chemoresistance. The nuclear transcription factor kappa B (NF-κB) family has been associated with apoptosis resistance and cellular invasion in RCC. The purpose of this study was to evaluate the impact of NF-κB1 gene silencing on the colony formation, cell migration and invasion abilities of the RCC cell line. Renca-mock and Renca-shRNA-NF-κB1 cells were used in this work. NF-κB1 downregulation was assessed by western blotting. The mRNA expression levels of interleukin-1 beta (IL-1ß) and MMP-9 were assessed by real-time quantitative polymerase chain reaction (RT-qPCR). The IL-1ß levels in the culture media were determined by a commercial ELISA kit. The MMP-9 protein expression and gelatinolytic activity were evaluated by western blotting and zymography, respectively, and the migration and invasion abilities were analysed. The expression levels of p105 and p50 in Renca-shRNA-NF-κBmoc1 cells were significantly reduced compared with those in the Renca-mock cells. The colony numbers of shRNA-NF-кB1 cells were lower than the colony numbers of the Renca-mock cells. NF-κB1 knockdown inhibited the cell migration and invasion of Renca-shRNA-NF-κB1 cells. These cells also exhibited reduced levels of IL-1ß. The MMP-9 expression and activity levels were significantly reduced in Renca-shRNA-NF-κB1 cells. Taken together, these results indicate that the downregulation of NF-κB1 suppresses the tumourigenicity of RCC by reducing MMP-9 expression and activity; thus, NF-κB1 could be a molecular target for RCC treatment.


Asunto(s)
Carcinoma de Células Renales/genética , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Interleucina-1beta/genética , Neoplasias Renales/genética , Metaloproteinasa 9 de la Matriz/genética , FN-kappa B/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular , Técnicas de Silenciamiento del Gen , Humanos , Interleucina-1beta/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , ARN Interferente Pequeño/genética
12.
Clin Sci (Lond) ; 133(17): 1901-1916, 2019 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-31471462

RESUMEN

NLRP3 inflammasome [NLR (nucleotide-binding domain, leucine-rich repeat containing protein) Pyrin-domain-containing 3 ] functions as an innate sensor of several PAMPs and DAMPs (pathogen- and damage-associated molecular patterns). It has been also reported as a transcription factor related to Th2 pattern, although its role in the adaptive immunity has been controversial, mainly because the studies were performed using gene deletion approaches. In the present study, we have investigated the NLRP3 gain-of-function in the context of encephalomyelitis autoimmune disease (EAE), considered to be a Th1- and Th17-mediated disease. We took advantage of an animal model with NLRP3 gain-of-function exclusively to T CD4+ lymphocytes (CD4CreNLRP3fl/fl). These mice presented reduced clinical score, accompanied by less infiltrating T CD4+ cells expressing both IFN-γ and IL-17 at the central nervous system (CNS) during the peak of the disease. However, besides NLRP3 gain-of-function in lymphocytes, these mice lack NLRP3 expression in non-T CD4+ cells. Therefore, in order to circumvent this deficiency, we transferred naive CD4+ T cells from WT, NLRP3-/- or CD4CreNLRP3fl/fl into Rag-1-/- mice and immunized them with MOG35-55 Likewise, the animals repopulated with CD4CreNLRP3fl/fl T CD4+ cells presented reduced clinical score and decreased IFN-γ production at the peak of the disease. Additionally, primary effector CD4+ T cells derived from these mice presented reduced glycolytic profile, a metabolic profile compatible with Th2 cells. Finally, naive CD4+ T cells from CD4CreNLRP3fl/fl mice under a Th2-related cytokine milieu cocktail exhibited in vitro an increased IL-4 and IL-13 production. Conversely, naive CD4+ T cells from CD4CreNLRP3fl/fl mice under Th1 differentiation produced less IFN-γ and T-bet. Altogether, our data evidence that the NLRP3 gain-of-function promotes a Th2-related response, a pathway that could be better explored in the treatment of multiple sclerosis.


Asunto(s)
Linfocitos T CD4-Positivos/metabolismo , Encefalomielitis Autoinmune Experimental/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Animales , Linfocitos T CD4-Positivos/inmunología , Citocinas/metabolismo , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Citometría de Flujo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células TH1/inmunología , Células TH1/metabolismo , Células Th17/inmunología , Células Th17/metabolismo
13.
Eur J Clin Microbiol Infect Dis ; 38(3): 515-521, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30680559

RESUMEN

A dipstick DNA chromatography assay, a single-tag hybridization-printed array strip (STH-PAS), was evaluated for its efficacy to detect dengue virus (DENV). Reverse-transcribed DNA was amplified by PCR, and the amplified DNA was detected using the STH-PAS system. The method was evaluated using stored RNA samples previously identified to carry all 4 serotypes of dengue, chikungunya, and influenza viruses. Clinical performance was also assessed in a prospective study using plasma from 269 febrile cases from the Emergency Department of St. Luke's Medical Center, Quezon City, Philippines, and 30 afebrile normal healthy volunteers. A Taqman real-time PCR (RT-PCR) assay and a rapid Dengue NS1 test, SD Bioline, were used for comparison. The STH-PAS system was more sensitive in detecting dengue infection compared to Taqman RT-PCR. For DENV serotypes 1, 2, and 3, the detection was 1 to 2 dilutions (10-fold) higher, and for DENV serotype 4, the detection was 2-4 dilutions higher. In clinical studies, the STH-PAS system showed 100% sensitivity with 88.9% and 86.6% specificities compared to Taqman RT-PCR and SD Dengue Duo NS1 test, respectively. The STH-PAS system was found to have a superior sensitivity than the Taqman system. Further evaluation of its performance in the field may provide important data to extend its usefulness for surveillance and epidemiological research in outbreak situations.


Asunto(s)
Cromatografía , Virus del Dengue/aislamiento & purificación , Dengue/diagnóstico , Virología/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Virus del Dengue/genética , Pruebas Diagnósticas de Rutina , Femenino , Humanos , Masculino , Persona de Mediana Edad , Filipinas , Estudios Prospectivos , ARN Viral/sangre , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Serogrupo , Adulto Joven
14.
BMC Complement Altern Med ; 19(1): 137, 2019 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-31215420

RESUMEN

BACKGROUND: The Cree of Eeyou Istchee (James Bay area of northern Quebec) suffer from a high rate of diabetes and its complications partly due to the introduction of the western lifestyle within their culture. As part of a search for alternative medicine based on traditional practice, this project evaluates the biological activity of Picea mariana (Mill.) Britton, Sterns & Poggenb. needle, bark, and cone, in preventing glucose toxicity to PC12-AC cells in vitro (a diabetic neurophathy model) and whether habitat and growth environment influence this activity. METHODS: Three different organs (needle, bark, and cone) of P. mariana were collected at different geographical locations and ecological conditions and their 80% ethanolic extracts were prepared. Extracts were then tested for their ability to protect PC12-AC cells from hyperglycaemic challenge at physiologically relevant concentrations of 0.25, 0.5, 1.0 and 2.0 µg/mL. Folin-Ciocalteu method was used to determine the total phenolic content of P. mariana extracts. RESULTS: All extracts were well-tolerated in vitro exhibiting LD50 of 25 µg/mL or higher. Extracts from all tested organs showed a cytoprotective concentration-dependent response. Furthermore, the cytoprotective activity was habitat- and growth environment-dependent with plants grown in bog or forest habitats in coastal or inland environments exhibiting different cytoprotective efficacies. These differences in activity correlated with total phenolic content but not with antioxidant activity. In addition, this paper provides the first complete Ultra-Performance Liquid Chromatography-quadrupole time-of-flight (UPLC-QTOF) mass spectrometry analysis of Picea mariana's bark, needles and cones. CONCLUSIONS: Together, these results provide further understanding of the cytoprotective activity of Canadian boreal forest plants identified by the Cree healers of Eeyou Istchee in a cell model of diabetic neuropathy. Their activity is relevant to diabetic peripheral neuropathic complications and shows that their properties can be optimized by harvesting in optimal growth environments.


Asunto(s)
Diabetes Mellitus/fisiopatología , Glucosa/toxicidad , Hipoglucemiantes/farmacología , Picea/química , Extractos Vegetales/farmacología , Sustancias Protectoras/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/metabolismo , Glucosa/metabolismo , Hipoglucemiantes/análisis , Células PC12 , Extractos Vegetales/análisis , Sustancias Protectoras/análisis , Quebec , Ratas
15.
Clin Genet ; 93(2): 378-381, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28661575

RESUMEN

High throughput approaches are continuously progressing and have become a major part of clinical diagnostics. Still, the critical process of detailed phenotyping and gathering clinical information has not changed much in the last decades. Forms of next generation phenotyping (NGP) are needed to increase further the value of any kind of genetic approaches, including timely consideration of (molecular) cytogenetics during the diagnostic quest. As NGP we used in this study the facial dysmorphology novel analysis (FDNA) technology to automatically identify facial phenotypes associated with Emanuel (ES) and Pallister-Killian Syndrome (PKS) from 2D facial photos. The comparison between ES or PKS and normal individuals expressed a full separation between the cohorts. Our results show that NPG is able to help in the clinic, and could reduce the time patients spend in diagnostic odyssey. It also helps to differentiate ES or PKS from each other and other patients with small supernumerary marker chromosomes, especially in countries with no access to more sophisticated genetic approaches apart from banding cytogenetics. Inclusion of more facial pictures of patient with sSMC, like isochromosome-18p-, cat-eye-syndrome or others may contribute to higher detection rates in future.


Asunto(s)
Trastornos de los Cromosomas/diagnóstico por imagen , Fisura del Paladar/diagnóstico por imagen , Anomalías del Ojo/diagnóstico por imagen , Cara/fisiopatología , Cardiopatías Congénitas/diagnóstico por imagen , Discapacidad Intelectual/diagnóstico por imagen , Hipotonía Muscular/diagnóstico por imagen , Aneuploidia , Trastornos de los Cromosomas/fisiopatología , Cromosomas Humanos Par 12 , Cromosomas Humanos Par 18/genética , Cromosomas Humanos Par 22 , Fisura del Paladar/fisiopatología , Análisis Citogenético/métodos , Anomalías del Ojo/fisiopatología , Cardiopatías Congénitas/fisiopatología , Humanos , Procesamiento de Imagen Asistido por Computador , Hibridación Fluorescente in Situ/métodos , Discapacidad Intelectual/fisiopatología , Cariotipificación , Mosaicismo , Hipotonía Muscular/fisiopatología , Fenotipo , Fotograbar
16.
J Nat Prod ; 81(10): 2169-2176, 2018 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-30336025

RESUMEN

Four new Δ12 ursene-type pentacyclic triterpenes containing the trans-feruloyl moiety (1-4), along with ursolic acid (5), were isolated from a Myrianthus arboreus root bark ethanol extract, after bioassay-guided subfractionation of its hexane fraction. The structures of 1-4 were established on the basis of the results of standard spectroscopic analytical methods (IR, HRESIMS, GC-MS, 1D and 2D NMR). The compounds 3ß- O- trans-feruloyl-2α,19α-dihydroxyurs-12-en-28-oic acid (1), 2α-acetoxy-3ß- O- trans-feruloyl-19α-hydroxyurs-12-en-28-oic acid (3), and 5 were determined to decrease the activity of hepatocellular glucose-6-phosphatase (G6Pase) and to activate glycogen synthase (GS). Their action on G6Pase activity implicated both Akt and AMPK activation. In addition, these compounds were determined to stimulate GS via the phosphorylation of glycogen synthase kinase-3. Compound 3 showed the most potent effect in modulating glucose homeostasis in liver cells. This is the first comprehensive report on novel phytochemical components of the root bark extract of M. arboreus based on the isolation of the principles responsible for its antidiabetic effects.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/farmacología , Triterpenos Pentacíclicos/farmacología , Corteza de la Planta/química , Extractos Vegetales/farmacología , Raíces de Plantas/química , Urticaceae/química , Línea Celular , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Glucosa/metabolismo , Glucosa-6-Fosfatasa/antagonistas & inhibidores , Glucógeno Sintasa/metabolismo , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Estructura Molecular
17.
BMC Complement Altern Med ; 18(1): 37, 2018 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-29378549

RESUMEN

BACKGROUND: Our team has identified 17 Boreal forest species from the traditional pharmacopeia of the Eastern James Bay Cree that presented promising in vitro and in vivo biological activities in the context of type 2 diabetes (T2D). We now screened the 17 plants extracts for potential anti-apoptotic activity in cultured kidney cells and investigated the underlying mechanisms. METHODS: MDCK (Madin-Darnby Canine Kidney) cell damage was induced by hypertonic medium (700 mOsm/L) in the presence or absence of maximal nontoxic concentrations of each of the 17 plant extracts. After 18 h' treatment, cells were stained with Annexin V (AnnV) and Propidium iodide (PI) and subjected to flow cytometry to assess the cytoprotective (AnnV-/PI-) and anti-apoptotic (AnnV+/PI-) potential of the 17 plant extracts. We then selected a representative subset of species (most cytoprotective, moderately so or neutral) to measure the activity of caspases 3, 8 and 9. RESULTS: Gaultheria hispidula and Abies balsamea are amongst the most powerful cytoprotective and anti-apoptotic plants and appear to exert their modulatory effect primarily by inhibiting caspase 9 in the mitochondrial apoptotic signaling pathway. CONCLUSION: We conclude that several Cree antidiabetic plants exert anti-apoptotic activity that may be relevant in the context of diabetic nephropathy (DN) that affects a significant proportion of Cree diabetics.


Asunto(s)
Hipoglucemiantes/farmacología , Medicina Tradicional , Extractos Vegetales/farmacología , Plantas Medicinales/química , Sustancias Protectoras/farmacología , Animales , Anexina A5/química , Apoptosis/efectos de los fármacos , Canadá , Caspasas/metabolismo , Nefropatías Diabéticas/metabolismo , Perros , Hipoglucemiantes/química , Células de Riñón Canino Madin Darby , Extractos Vegetales/química , Propidio/química , Sustancias Protectoras/química
18.
Biochem Biophys Res Commun ; 493(1): 869-874, 2017 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-28928090

RESUMEN

Phyllanthus niruri is used in herbal medicine for treatment of diabetes. The objective of this study was to investigate the antidiabetic potential of P. niruri, using assays for α-glucosidase, muscle glucose transport, liver glucose production and adipogenesis. α-Glucosidase inhibitory activity was performed on aqueous and ethanolic extract of aerial parts of P. niruri. The aqueous and ethanolic extract of P. niruri showed α-glucosidase inhibitory activity with IC50 values of 3.7 ± 1.1 and 6.3 ± 4.8 µg/mL, respectively. HR-bioassay/HPLC-HRMS and NMR analysis was used for identification of compounds. Corilagin (1) and repandusinic acid A (2) were identified as α-glucosidase inhibitors in the water extract of P. niruri with IC50 values of 0.9 ± 0.1 and 1.9 ± 0.02 µM, respectively. In in vitro cell-based bioassays, cells were treated for 18 h with maximal non-toxic concentrations of the ethanolic extract of P. niruri, which were determined by the lactate dehydrogenase cytotoxicity assay. The ethanolic extract of P. niruri was not able to reduce glucose-6-phosphatase activity. However, the extract increased deoxyglucose uptake in C2C12 muscle cells and enhanced adipogenesis in 3T3-L1 fat cells which has been reported for the first time. The present study demonstrated that P. niruri may thus have potential application for treatment and/or management of type 2 diabetes.


Asunto(s)
Adipogénesis/efectos de los fármacos , Glucosa/metabolismo , Hipoglucemiantes/administración & dosificación , Hígado/metabolismo , Músculo Esquelético/metabolismo , Phyllanthus/química , alfa-Glucosidasas/metabolismo , Células 3T3 , Animales , Bioensayo , Relación Dosis-Respuesta a Droga , Estudios de Factibilidad , Hígado/efectos de los fármacos , Ratones , Músculo Esquelético/efectos de los fármacos , Extractos Vegetales/administración & dosificación , Resultado del Tratamiento
19.
Ecology ; 98(7): 1896-1907, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28419436

RESUMEN

Functional gene approaches have been used to better understand the roles of microbes in driving forest soil nitrogen (N) cycling rates and bioavailability. Ammonia oxidation is a rate limiting step in nitrification, and is a key area for understanding environmental constraints on N availability in forests. We studied how increasing temperature affects the role of ammonia oxidizing archaea (AOA) and bacteria (AOB) in soil N cycling and availability by using a highly constrained natural mean annual temperature (MAT) elevation gradient in a tropical montane wet forest. We found that net nitrate (NO3- ) bioavailability is positively related to MAT (r2  = 0.79, P = 0.0033), and AOA DNA abundance is positively related to both NO3- availability (r2  = 0.34, P = 0.0071) and MAT (r2  = 0.34, P < 0.001). In contrast, AOB DNA was only detected in some soils across the gradient. We identified three distinct phylotypes within the AOA which differed from one another in abundance and relative gene expression. In addition, one AOA phylotype increased in abundance with MAT, while others did not. We conclude that MAT is the primary driver of ecosystem N availability across this gradient, and AOA population size and structure appear to mediate the relationship between the nitrification and N bioavailability. These findings hold important implications for nutrient limitation in forests and feedbacks to primary production under changing climate.


Asunto(s)
Amoníaco/metabolismo , Ecosistema , Ciclo del Nitrógeno , Microbiología del Suelo , Temperatura , Archaea , Nitrificación , Nitrógeno , Oxidación-Reducción , Suelo , Clima Tropical
20.
Neuropediatrics ; 48(3): 166-184, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28561207

RESUMEN

We investigated the genetic, phenotypic, and interferon status of 46 patients from 37 families with neurological disease due to mutations in ADAR1. The clinicoradiological phenotype encompassed a spectrum of Aicardi-Goutières syndrome, isolated bilateral striatal necrosis, spastic paraparesis with normal neuroimaging, a progressive spastic dystonic motor disorder, and adult-onset psychological difficulties with intracranial calcification. Homozygous missense mutations were recorded in five families. We observed a p.Pro193Ala variant in the heterozygous state in 22 of 23 families with compound heterozygous mutations. We also ascertained 11 cases from nine families with a p.Gly1007Arg dominant-negative mutation, which occurred de novo in four patients, and was inherited in three families in association with marked phenotypic variability. In 50 of 52 samples from 34 patients, we identified a marked upregulation of type I interferon-stimulated gene transcripts in peripheral blood, with a median interferon score of 16.99 (interquartile range [IQR]: 10.64-25.71) compared with controls (median: 0.93, IQR: 0.57-1.30). Thus, mutations in ADAR1 are associated with a variety of clinically distinct neurological phenotypes presenting from early infancy to adulthood, inherited either as an autosomal recessive or dominant trait. Testing for an interferon signature in blood represents a useful biomarker in this context.


Asunto(s)
Adenosina Desaminasa/genética , Enfermedades Autoinmunes del Sistema Nervioso/genética , Enfermedades Autoinmunes del Sistema Nervioso/inmunología , Interferón Tipo I/metabolismo , Malformaciones del Sistema Nervioso/genética , Malformaciones del Sistema Nervioso/inmunología , Proteínas de Unión al ARN/genética , Adolescente , Adulto , Enfermedades Autoinmunes del Sistema Nervioso/diagnóstico por imagen , Biomarcadores/metabolismo , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Mutación , Malformaciones del Sistema Nervioso/diagnóstico por imagen , Fenotipo , Adulto Joven
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