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1.
J Immunol ; 211(4): 626-632, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37387671

RESUMO

The transcription factor retinoic acid-related orphan receptor α (RORα) is important in regulating several physiological functions, such as cellular development, circadian rhythm, metabolism, and immunity. In two in vivo animal models of type 2 lung inflammation, Nippostrongylus brasiliensis infection and house dust mite (HDM) sensitization, we show a role for Rora in Th2 cellular development during pulmonary inflammation. N. brasiliensis infection and HDM challenge induced an increase in frequency of Rora-expressing GATA3+CD4 T cells in the lung. Using staggerer mice, which have a ubiquitous deletion of functional RORα, we generated bone marrow chimera mice, and we observed a delayed worm expulsion and reduced frequency in the expansion of Th2 cells and innate lymphoid type 2 cells (ILC2s) in the lungs after N. brasiliensis infection. ILC2-deficient mouse (Rorafl/flIl7raCre) also had delayed worm expulsion with associated reduced frequency of Th2 cells and ILC2s in the lungs after N. brasiliensis infection. To further define the role for Rora-expressing Th2 cells, we used a CD4-specific Rora-deficient mouse (Rorafl/flCD4Cre), with significantly reduced frequency of lung Th2 cells, but not ILC2, after N. brasiliensis infection and HDM challenge. Interestingly, despite the reduction in pulmonary Th2 cells in Rorafl/flCD4Cre mice, this did not impact the expulsion of N. brasiliensis after primary and secondary infection, or the generation of lung inflammation after HDM challenge. This study demonstrates a role for RORα in Th2 cellular development during pulmonary inflammation that could be relevant to the range of inflammatory diseases in which RORα is implicated.


Assuntos
Imunidade Inata , Pneumonia , Camundongos , Animais , Células Th2 , Receptor alfa de Ácido Retinoico , Linfócitos T CD4-Positivos , Tretinoína
2.
Plant Dis ; : PDIS07231412RE, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38213118

RESUMO

The reniform nematode (Rotylenchulus reniformis Linford and Oliveira) adversely impacts the quality and quantity of sweetpotato storage roots. Management of R. reniformis in sweetpotato remains a challenge because host plant resistance is not available, fumigants are detrimental to the environment and health, and crop rotation is not effective. We screened a core set of 24 sweetpotato plant introductions (PIs) against R. reniformis. Four PIs were resistant, and 10 were moderately resistant to R. reniformis, suggesting these PIs can serve as sources of resistance for sweetpotato resistance breeding programs. PI 595869, PI 153907, and PI 599386 suppressed 83 to 89% egg production relative to the susceptible control 'Beauregard', and these PIs were employed in subsequent experiments to determine if their efficacy against R. reniformis can be further increased by applying nonfumigant nematicides oxamyl, fluopyram, and fluensulfone. A 34 to 93% suppression of nematode reproduction was achieved by the application of nonfumigant nematicides, with oxamyl providing the best suppression followed by fluopyram and fluensulfone. Although sweetpotato cultivars resistant to R. reniformis are currently not available and there is a need for the development of safer yet highly effective nonfumigant nematicides, results from the current study suggest that complementing host plant resistance with nonfumigant nematicides can serve as an important tool for effective and sustainable nematode management.

3.
Int J Mol Sci ; 25(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38612562

RESUMO

Fracture healing is a complex series of events that requires a local inflammatory reaction to initiate the reparative process. This inflammatory reaction is important for stimulating the migration and proliferation of mesenchymal progenitor cells from the periosteum and surrounding tissues to form the cartilaginous and bony calluses. The proinflammatory cytokine interleukin (IL)-17 family has gained attention for its potential regenerative effects; however, the requirement of IL-17 signaling within mesenchymal progenitor cells for normal secondary fracture healing remains unknown. The conditional knockout of IL-17 receptor a (Il17ra) in mesenchymal progenitor cells was achieved by crossing Il17raF/F mice with Prx1-cre mice to generate Prx1-cre; Il17raF/F mice. At 3 months of age, mice underwent experimental unilateral mid-diaphyseal femoral fractures and healing was assessed by micro-computed tomography (µCT) and histomorphometric analyses. The effects of IL-17RA signaling on the osteogenic differentiation of fracture-activated periosteal cells was investigated in vitro. Examination of the intact skeleton revealed that the conditional knockout of Il17ra decreased the femoral cortical porosity but did not affect any femoral trabecular microarchitectural indices. After unilateral femoral fractures, Il17ra conditional knockout impacted the cartilage and bone composition of the fracture callus that was most evident early in the healing process (day 7 and 14 post-fracture). Furthermore, the in vitro treatment of fracture-activated periosteal cells with IL-17A inhibited osteogenesis. This study suggests that IL-17RA signaling within Prx1+ mesenchymal progenitor cells can influence the early stages of endochondral ossification during fracture healing.


Assuntos
Fraturas do Fêmur , Proteínas de Homeodomínio , Células-Tronco Mesenquimais , Receptores de Interleucina-17 , Animais , Camundongos , Consolidação da Fratura , Inflamação , Osteogênese , Microtomografia por Raio-X , Receptores de Interleucina-17/genética , Receptores de Interleucina-17/metabolismo , Proteínas de Homeodomínio/metabolismo
4.
Environ Sci Technol ; 57(51): 21815-21822, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38085788

RESUMO

Per- and polyfluoroalkyl substances (PFAS), nicknamed "forever chemicals" due to the strength of their carbon-fluorine bonds, are a class of potent micropollutants that cause deleterious health effects in mammals. The current state-of-the-art detection method requires the collection and transport of water samples to a centralized facility where chromatography and mass spectrometry are performed for the separation, identification, and quantification of PFAS. However, for efficient remediation efforts to be properly informed, a more rapid in-field testing method is required. We previously demonstrated the development and use of dioxygen as the mediator molecule. The use of dioxygen is predicated on the assumption that there will be consistent ambient dioxygen levels in natural waters. This is not always the case in hypoxic groundwater and at high altitudes. To overcome this challenge and further advance the strategies that will enable in-field electroanalysis of PFAS, we demonstrate, as a proof of concept, that dioxygen can be generated in solution through the hydrolysis of water. The electrogenerated dioxygen can then be used as a mediator molecule for the indirect detection of PFOS via molecularly imprinted polymer (MIP)-based electroanalysis. We demonstrate that calibration curves can be constructed with high precision and sensitivity (LOD < 1 ppt or 1 ng/L). Our results provide a foundation for enabling in-field hypoxic PFAS electroanalysis.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Animais , Rios , Oxigênio/análise , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Água , Mamíferos
5.
Plant Dis ; 107(8): 2346-2351, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36627801

RESUMO

Biochar, compost, and biological control agents can suppress pathogens on their own; however, their reliability and efficacy are not as acceptable as synthetic fungicides commonly used to suppress pathogens. A multiyear field study was initiated to evaluate combinations of monthly applications of a biochar compost mixture and weekly or biweekly Bacillus subtilis QST713 applications for their ability to suppress foliar pathogens on a creeping bentgrass (Agrostis stolonifera L.) fairway and to measure their impact on strain QST713 establishment. Disease severity and turfgrass quality were measured every 14 days throughout the growing season. Populations of strain QST713 were quantified by quantitative PCR analysis on DNA extracted from foliage samples collected throughout the trial. Biochar compost mixture applications increased turfgrass quality in both years of the study and reduced dollar spot (Clarireedia jacksonii Salgado-Salazar) severity in 2021. Weekly strain QST713 applications reduced copper spot (Gloeocercospora sorghi D. C. Bain & Edgerton) severity compared with biweekly applications and the nontreated control in 2020, yet monthly biochar compost mixture with weekly strain QST713 applications completely suppressed copper spot in 2021. Populations of strain QST713 were highest in weekly treated plots, and monthly biochar compost mixture applications did not affect strain QST713 establishment. Although there was not an interaction between biochar compost mixture and strain QST713 applications, implementing both in a season-long program will benefit turfgrass health and reduce disease severity.


Assuntos
Agrostis , Compostagem , Cobre , Reprodutibilidade dos Testes
6.
J Nematol ; 55(1): 20230025, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37284001

RESUMO

Meloidogyne enterolobii is a highly aggressive quarantine pathogen which threatens the multibillion-dollar tobacco industry and is not manageable with the currently available management methods in tobacco. There is currently no known host plant resistance in tobacco and previous studies have shown that the lower level of the currently recommended rate of non-fumigant nematicides does not provide satisfactory management of M. enterolobii. The current study was conducted with the hypothesis that M. enterolobii can be better managed using a single soil application of the maximum allowed rate of non-fumigant nematicides. Treatments involved three non-fumigant chemical nematicides (oxamyl, fluopyram, and fluensulfone), a biological nematicide derived from Burkholderia, and a non-treated control. Fluensulfone significantly suppressed the nematode reproduction relative to the control, the suppression being 71% for eggs and 86% for the second stage juveniles (J2). Fluopyram also suppressed nematode reproduction, although this was statistically insignificant, with the suppression being 26% and 37% for eggs and J2, respectively. Oxamyl significantly suppressed J2 (80%), but not eggs (50%) in relation to the control. The most significant reduction of disease severity was achieved by the application of fluensulfone (64%), followed by oxamyl (54%) and fluopyram (48%). Except for fluensulfone, which significantly reduced the root biomass, none of the nematicides significantly impacted root and shoot biomass. The biological nematicide did not significantly affect nematode reproduction, pathogenicity, or disease severity. The results from the current study suggest that while the non-fumigant nematicides provided a good level of the nematode suppression, more research is needed to improve the efficacy of non-fumigant nematicides through employing better application methods or finding better chemistries.

7.
Plant Dis ; 106(2): 641-647, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34633241

RESUMO

Pythium root rot (PRR) is a disease that can rapidly devastate large swaths of golf course putting greens, with little recourse once symptoms appear. Golf courses routinely apply preventive fungicides for root diseases, which may alter the rhizosphere microbiome, leading to unintended effects on plant health. A multiyear field trial was initiated on a 'T-1' creeping bentgrass (Agrostis stolonifera L. cultivar T-1) putting green in College Park, Maryland to evaluate preventive PRR management for disease suppression and effects on rhizosphere bacterial communities. Fungicides commonly used to prevent PRR and a biological fungicide were repeatedly applied to experimental plots throughout the growing season. Rhizosphere samples were collected twice annually from each plot for evaluation of rhizosphere bacterial communities through amplicon sequencing and monitoring of biological control organism populations via quantitative PCR. Cyazofamid was the only treatment to suppress PRR in both years compared with the control. Fosetyl-Al on a 14-day interval and Bacillus subtilis QST713 also reduced PRR severity in 2019 compared with the nontreated control. Treatments did not significantly affect bacterial diversity or relative abundances of bacterial classes; however, seasonal environmental changes did. Repeated rhizosphere-targeted applications of B. subtilis QST713 appear to have established the bacterium into the rhizosphere, as populations increased between samples, even after applications stopped. These findings suggest that QST713 may reduce pathogen pressure when repeatedly applied and can reduce fungicide usage during periods of low PRR pressure.


Assuntos
Agrostis , Fungicidas Industriais , Pythium , Agrostis/microbiologia , Bactérias , Fungicidas Industriais/farmacologia , Rizosfera
8.
J Pers Assess ; 104(2): 221-233, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35112940

RESUMO

This paper examines the utility of the Trauma Symptom Inventory-2 (TSI-2) and its predecessor, the Trauma Symptom Inventory (TSI) in forensic psychology practice. The instrument's psychometric properties, use with special populations, legal case review and admissibility considerations are discussed. Recommendations regarding the strengths and limitations of the TSI/TSI-2 are suggested for forensic practitioners and lawyers. Considerations related to potential expert witness cross-examination are also presented. Psychological research and legal review suggest that the TSI/TSI-2 is admissible as an instrument under the Daubert Standard, especially as related to civil court disability claims. Still, lingering issues with the ATR validity scale remain and there is limited independent research establishing the predictive and discriminant validity of the TSI-2 across diverse forensic samples. In summary, this suggests the instrument is most effective as part of a comprehensive assessment battery for identifying PTSD symptomology within legal proceedings where a trauma diagnosis is relevant.


Assuntos
Transtornos de Estresse Pós-Traumáticos , Humanos , Organizações , Psicometria , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/psicologia
9.
HEC Forum ; 34(3): 233-255, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32494992

RESUMO

In Pharmaceutical Freedom Professor Flanigan argues we ought to grant people self-medication rights for the same reasons we respect people's right to give (or refuse to give) informed consent to treatment. Despite being the most comprehensive argument in favour of self-medication written to date, Flanigan's Pharmaceutical Freedom leaves a number of questions unanswered, making it unclear how the safe-guards Flanigan incorporates to protect people from harming themselves would work in practice. In this paper, I extend Professor Flanigan's account by discussing a hypothetical case to illustrate how these safe-guards could work together to protect people from harms caused by their own ignorance or incompetence.


Assuntos
Liberdade , Consentimento Livre e Esclarecido , Humanos
10.
Med Law Int ; 21(1): 42-68, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33958837

RESUMO

In response to slow progress regarding technological innovations to manage type 1 diabetes, some patients have created unregulated do-it-yourself artificial pancreas systems (DIY APS). Yet both in the United Kingdom (UK) and internationally, there is an almost complete lack of specific guidance - legal, regulatory, or ethical - for clinicians caring for DIY APS users. Uncertainty regarding their professional obligations has led to them being cautious about discussing DIY APS with patients, let alone recommending or prescribing them. In this article, we argue that this approach threatens to undermine trust and transparency. Analysing the professional guidance from the UK regulator - the General Medical Council - we demonstrate that nothing within it ought to be interpreted as precluding clinicians from initiating discussions about DIY APS. Moreover, in some circumstances, it may require that clinicians do so. We also argue that the guidance does not preclude clinicians from prescribing such unapproved medical devices.

11.
New Phytol ; 228(3): 1055-1069, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32521050

RESUMO

Macroorganisms' genotypes shape their phenotypes, which in turn shape the habitat available to potential microbial symbionts. This influence of host genotype on microbiome composition has been demonstrated in many systems; however, most previous studies have either compared unrelated genotypes or delved into molecular mechanisms. As a result, it is currently unclear whether the heritability of host-associated microbiomes follows similar patterns to the heritability of other complex traits. We take a new approach to this question by comparing the microbiomes of diverse maize inbred lines and their F1 hybrid offspring, which we quantified in both rhizosphere and leaves of field-grown plants using 16S-v4 and ITS1 amplicon sequencing. We show that inbred lines and hybrids differ consistently in the composition of bacterial and fungal rhizosphere communities, as well as leaf-associated fungal communities. A wide range of microbiome features display heterosis within individual crosses, consistent with patterns for nonmicrobial maize phenotypes. For leaf microbiomes, these results were supported by the observation that broad-sense heritability in hybrids was substantially higher than narrow-sense heritability. Our results support our hypothesis that at least some heterotic host traits affect microbiome composition in maize.


Assuntos
Microbiota , Rizosfera , Vigor Híbrido/genética , Microbiota/genética , Folhas de Planta/genética , Zea mays/genética
13.
Phytopathology ; 108(1): 23-30, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28846056

RESUMO

Bacterial etiolation and decline has developed into a widespread issue with creeping bentgrass (CBG) (Agrostis stolonifera) putting green turf. The condition is characterized by an abnormal elongation of turfgrass stems and leaves that in rare cases progresses into a rapid and widespread necrosis and decline. Recent reports have cited bacteria, Acidovorax avenae and Xanthomonas translucens, as causal agents; however, few cases exist where either bacterium were isolated in conjunction with turf exhibiting bacterial disease symptoms. From 2010 to 2014, turfgrass from 62 locations submitted to the NC State Turf Diagnostic Clinic exhibiting bacterial etiolation and/or decline symptoms were sampled for the presence of bacterial pathogens. Isolated bacteria were identified using rRNA sequencing of the 16S subunit and internal transcribed spacer region (16S-23S or ITS). Results showed diverse bacteria isolated from symptomatic turf and A. avenae and X. translucens were only isolated in 26% of samples. Frequently isolated bacterial species were examined for pathogenicity to 4-week-old 'G2' CBG seedlings and 8-week-old 'A-1' CBG turfgrass stands in the greenhouse. While results confirmed pathogenicity of A. avenae and X. translucens, Pantoea ananatis was also shown to infect CBG turf; although pathogenicity varied among isolated strains. These results illustrate that multiple bacteria are associated with bacterial disease and shed new light on culturable bacteria living in CBG turfgrass putting greens. Future research to evaluate additional microorganisms (i.e., bacteria and fungi) could provide new information on host-microbe interactions and possibly develop ideas for management tactics to reduce turfgrass pests.


Assuntos
Agrostis/microbiologia , Bactérias/isolamento & purificação , Doenças das Plantas/microbiologia , Agrostis/fisiologia , Bactérias/classificação , Bactérias/genética , Bactérias/patogenicidade , Estiolamento , Filogenia , Folhas de Planta/microbiologia , Folhas de Planta/fisiologia , Análise de Sequência de DNA , Virulência
14.
Curr Osteoporos Rep ; 16(2): 146-154, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29441447

RESUMO

PURPOSE OF REVIEW: Growing evidence supports the critical role of transcriptional mechanisms in promoting the spatial and temporal progression of bone healing. In this review, we evaluate and discuss new transcriptional and post-transcriptional regulatory mechanisms of secondary bone repair, along with emerging evidence for epigenetic regulation of fracture healing. RECENT FINDINGS: Using the candidate gene approach has identified new roles for several transcription factors in mediating the reactive, reparative, and remodeling phases of fracture repair. Further characterization of the different epigenetic controls of fracture healing and fracture-driven transcriptome changes between young and aged fracture has identified key biological pathways that may yield therapeutic targets. Furthermore, exogenously delivered microRNA to post-transcriptionally control gene expression is quickly becoming an area with great therapeutic potential. Activation of specific transcriptional networks can promote the proper progression of secondary bone healing. Targeting these key factors using small molecules or through microRNA may yield effective therapies to enhance and possibly accelerate fracture healing.


Assuntos
Remodelação Óssea/genética , Consolidação da Fratura/genética , Regulação da Expressão Gênica , MicroRNAs , Osteogênese/genética , Fatores de Transcrição/genética , Fatores Etários , Epigênese Genética , Expressão Gênica , Humanos
15.
J Foot Ankle Surg ; 57(4): 681-684, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29627135

RESUMO

Plantar fascia release and calcaneal slide osteotomy are often components of the surgical management for cavovarus deformities of the foot. In this setting, plantar fascia release has traditionally been performed through an incision over the medial calcaneal tuberosity, and the calcaneal osteotomy through a lateral incision. Two separate incisions can potentially increase the operative time and morbidity. The purpose of the present study was threefold: to describe the operative technique, use cadaveric dissection to analyze whether a full release of the plantar fascia was possible through the lateral incision, and examine the proximity of the medial neurovascular structures to both the plantar fascia release and calcaneal slide osteotomy when performed together. In our cadaveric dissections, we found that full release of the plantar fascia is possible through the lateral incision with no obvious damage to the medial neurovascular structures. We also found that the calcaneal branch of the tibial nerve reliably crossed the osteotomy in all specimens. We have concluded that both the plantar fascia release and the calcaneal osteotomy can be safely performed through a lateral incision, if care is taken when completing the calcaneal osteotomy to ensure that the medial neurovascular structures remain uninjured.


Assuntos
Aponeurose/cirurgia , Calcâneo/cirurgia , Dissecação/métodos , Fasciotomia/métodos , Pé Chato/cirurgia , Osteotomia/métodos , Idoso , Idoso de 80 Anos ou mais , Cadáver , Feminino , Humanos , Masculino
16.
HEC Forum ; 30(3): 235-252, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29290005

RESUMO

In light of the variety of uses of the term autonomy in recent bioethics literature, in this paper, I suggest that competence, not being as contested, is better placed to play the anti-paternalistic role currently assigned to autonomy. The demonstration of competence, I will argue, can provide individuals with robust spheres of non-interference in which they can pursue their lives in accordance with their own values. This protection from paternalism is achieved by granting individuals rights to non-interference upon demonstration of competence. In this paper, I present a risk-sensitive account of competence as a means of grounding rights to non-interference. On a risk-sensitive account of competence individuals demonstrate their competence by exercising three capacities to the extent necessary to meet a threshold determined by the riskiness of the decision. These three capacities are the capacity to (i) acquire knowledge, (ii) use instrumental rationality, and (iii) form and revise a life plan.


Assuntos
Competência Clínica/normas , Tomada de Decisões , Padrões de Prática Médica/normas , Autonomia Profissional , Humanos , Paternalismo , Política , Padrões de Prática Médica/ética , Padrões de Prática Médica/tendências
17.
Biochim Biophys Acta ; 1861(3): 166-76, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26680362

RESUMO

The activation of hepatic kinase mechanistic target of rapamycin complex 1 (mTORC1) is implicated in the development of obesity-related metabolic disorders. This study investigated the metabolic sequelae of mTORC1 hyperactivation in human hepatoma cells and the lipid-regulating mechanisms of two short-chain fatty acids: 4-phenylbutyric acid (PBA) and (R)-α-lipoic acid (LA). We created three stable cell lines that exhibit low, normal, or high mTORC1 activity. mTORC1 hyperactivation induced the expression of lipogenic (DGAT1 and DGAT2) and lipoprotein assembly (MTP and APOB) genes, thereby raising cellular triacylglyceride (TG) and exacerbating secretion of apoB-containing TG-rich lipoproteins. LYS6K2, a specific inhibitor of the p70 S6 kinase branch of mTORC1 signaling, reversed these effects. PBA and LA decreased secreted TG through distinct mechanisms. PBA repressed apoB expression (both mRNA and protein) and lowered secreted TG without mitigation of mTORC1 hyperactivity or activation of AMPK. LA decreased cellular and secreted TG by attenuating mTORC1 signaling in an AMPK-independent manner. LA did not regulate apoB expression but led to the secretion of apoB-containing TG-poor lipoproteins by repressing the expression of lipogenic genes, FASN, DGAT1, and DGAT2. Our studies provide new mechanistic insight into the hypolipidemic activity of PBA and LA in the context of mTORC1 hyperactivation and suggest that the short-chain fatty acids may aid in the prevention and treatment of hypertriglyceridemia.


Assuntos
Apolipoproteína B-100/metabolismo , Carcinoma Hepatocelular/metabolismo , Hipertrigliceridemia/tratamento farmacológico , Neoplasias Hepáticas/enzimologia , Complexos Multiproteicos/metabolismo , Fenilbutiratos/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Ácido Tióctico/farmacologia , Triglicerídeos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apolipoproteína B-100/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Células Hep G2 , Humanos , Hipertrigliceridemia/genética , Hipertrigliceridemia/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Complexos Multiproteicos/antagonistas & inibidores , Complexos Multiproteicos/genética , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Proteína Regulatória Associada a mTOR , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/genética , Transfecção , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Regulação para Cima
18.
J Clin Immunol ; 36(5): 462-71, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27076228

RESUMO

The purpose of this research was to use next generation sequencing to identify mutations in patients with primary immunodeficiency diseases whose pathogenic gene mutations had not been identified. Remarkably, four unrelated patients were found by next generation sequencing to have the same heterozygous mutation in an essential donor splice site of PIK3R1 (NM_181523.2:c.1425 + 1G > A) found in three prior reports. All four had the Hyper IgM syndrome, lymphadenopathy and short stature, and one also had SHORT syndrome. They were investigated with in vitro immune studies, RT-PCR, and immunoblotting studies of the mutation's effect on mTOR pathway signaling. All patients had very low percentages of memory B cells and class-switched memory B cells and reduced numbers of naïve CD4+ and CD8+ T cells. RT-PCR confirmed the presence of both an abnormal 273 base-pair (bp) size and a normal 399 bp size band in the patient and only the normal band was present in the parents. Following anti-CD40 stimulation, patient's EBV-B cells displayed higher levels of S6 phosphorylation (mTOR complex 1 dependent event), Akt phosphorylation at serine 473 (mTOR complex 2 dependent event), and Akt phosphorylation at threonine 308 (PI3K/PDK1 dependent event) than controls, suggesting elevated mTOR signaling downstream of CD40. These observations suggest that amino acids 435-474 in PIK3R1 are important for its stability and also its ability to restrain PI3K activity. Deletion of Exon 11 leads to constitutive activation of PI3K signaling. This is the first report of this mutation and immunologic abnormalities in SHORT syndrome.


Assuntos
Linfócitos B/imunologia , Transtornos do Crescimento/genética , Síndrome de Imunodeficiência com Hiper-IgM/genética , Hipercalcemia/genética , Doenças Metabólicas/genética , Mutação/genética , Nefrocalcinose/genética , Fosfatidilinositol 3-Quinases/genética , Processamento Alternativo/genética , Linhagem Celular Transformada , Criança , Pré-Escolar , Classe Ia de Fosfatidilinositol 3-Quinase , Anormalidades Craniofaciais , Análise Mutacional de DNA , Nanismo , Orelha/anormalidades , Feminino , Genes Dominantes , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Linfadenopatia , Masculino , Pescoço/anormalidades , Proteínas Quinases S6 Ribossômicas/metabolismo , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/metabolismo , Tórax/anormalidades
19.
Blood ; 124(13): 2046-50, 2014 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-25139357

RESUMO

Identification of the molecular etiologies of primary immunodeficiencies has led to important insights into the development and function of the immune system. We report here the cause of combined immunodeficiency in 4 patients from 2 different consanguineous Qatari families with similar clinical and immunologic phenotypes. The patients presented at an early age with fungal, viral, and bacterial infections and hypogammaglobulinemia. Although their B- and T-cell numbers were normal, they had low regulatory T-cell and NK-cell numbers. Moreover, patients' T cells were mostly CD45RA(+)-naive cells and were defective in activation after T-cell receptor stimulation. All patients contained the same homozygous nonsense mutation in IKBKB (R286X), revealed by whole-exome sequencing with undetectable IKKß and severely decreased NEMO proteins. Mutant IKKß(R286X) was unable to complex with IKKα/NEMO. Immortalized patient B cells displayed impaired IκBα phosphorylation and NFκB nuclear translocation. These data indicate that mutated IKBKB is the likely cause of immunodeficiency in these 4 patients.


Assuntos
Códon sem Sentido , Quinase I-kappa B/genética , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/imunologia , Família , Feminino , Homozigoto , Humanos , Lactente , Masculino , Imunodeficiência Combinada Severa/diagnóstico , Imunodeficiência Combinada Severa/terapia , Resultado do Tratamento
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