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1.
Appl Opt ; 63(1): 159-166, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175017

RESUMO

A fiber-connectorized K-band integrated-optics two-telescope beam combiner was developed for long-baseline interferometry at the CHARA telescope array utilizing the ultrafast laser inscription (ULI) technique. Single-mode waveguide insertion losses were measured to be ∼1.1d B over the 2-2.3 µm window. The development of asymmetric directional couplers enabled the construction of a beam combiner that includes a 50:50 coupler for interferometric combination and two ∼75:25 couplers for photometric calibration. The visibility of the bare beam combiner was measured at 87% and then at 82% after fiber-connectorization by optimizing the input polarization. These results indicate that ULI technique can fabricate efficient fiber-connectorized K-band beam combiners for astronomical purposes.

2.
PeerJ ; 11: e16004, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37701841

RESUMO

There is a lack of cost-effective, environmentally-friendly tools available to manage marine biofouling accumulation on static artificial structures such as drilling rigs, wind turbines, marine farms, and port and marina infrastructure. For there to be uptake and refinement of tools, emerging technologies need to be tested and proven at an operational scale. This study aimed to see whether biofouling accumulation could be suppressed on marine infrastructure under real-world conditions through the delivery of continuous bubble streams. Submerged surfaces of a floating marina pontoon were cleaned in-situ by divers, and the subsequent colonisation by biofouling organisms was monitored on treated (bubbles applied) and untreated sections. Continuous bubble streams proved highly effective (>95%) in controlling macrofouling accumulation on the underside surface of the marina pontoon for the first 2 months after deployment, but efficacy dropped off rapidly once bubble stream delivery was partially obscured due to biofouling accumulation on the diffuser itself. Although extensive macrofouling cover by mussels, bryozoans and hydroids was observed on treated surfaces by 4 months (27.5%, SE = 4.8%), biofouling % cover and diversity was significantly higher on untreated surfaces (79.6%, SE = 2.9%). While this study demonstrates that continuous bubble streams greatly restrict biofouling accumulation over short-to-medium timescales, improved system design, especially the incorporation of diffusers resistant to fouling, is needed for the approach to be considered a viable long-term option for biofouling management on static artificial structures.


Assuntos
Incrustação Biológica , Briozoários , Fabaceae , Animais , Incrustação Biológica/prevenção & controle , Transporte Biológico , Fazendas
3.
Eur Respir J ; 61(5)2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36922030

RESUMO

BACKGROUND: COVID-19 is associated with a dysregulated immune response but it is unclear how immune dysfunction contributes to the chronic morbidity persisting in many COVID-19 patients during convalescence (long COVID). METHODS: We assessed phenotypical and functional changes of monocytes in COVID-19 patients during hospitalisation and up to 9 months of convalescence following COVID-19, respiratory syncytial virus or influenza A. Patients with progressive fibrosing interstitial lung disease were included as a positive control for severe, ongoing lung injury. RESULTS: Monocyte alterations in acute COVID-19 patients included aberrant expression of leukocyte migration molecules, continuing into convalescence (n=142) and corresponding with specific symptoms of long COVID. Long COVID patients with unresolved lung injury, indicated by sustained shortness of breath and abnormal chest radiology, were defined by high monocyte expression of C-X-C motif chemokine receptor 6 (CXCR6) (p<0.0001) and adhesion molecule P-selectin glycoprotein ligand 1 (p<0.01), alongside preferential migration of monocytes towards the CXCR6 ligand C-X-C motif chemokine ligand 16 (CXCL16) (p<0.05), which is abundantly expressed in the lung. Monocyte CXCR6 and lung CXCL16 were heightened in patients with progressive fibrosing interstitial lung disease (p<0.001), confirming a role for the CXCR6-CXCL16 axis in ongoing lung injury. Conversely, monocytes from long COVID patients with ongoing fatigue exhibited a sustained reduction of the prostaglandin-generating enzyme cyclooxygenase 2 (p<0.01) and CXCR2 expression (p<0.05). These monocyte changes were not present in respiratory syncytial virus or influenza A convalescence. CONCLUSIONS: Our data define unique monocyte signatures that define subgroups of long COVID patients, indicating a key role for monocyte migration in COVID-19 pathophysiology. Targeting these pathways may provide novel therapeutic opportunities in COVID-19 patients with persistent morbidity.


Assuntos
COVID-19 , Influenza Humana , Lesão Pulmonar , Humanos , Monócitos/metabolismo , Quimiocinas CXC/metabolismo , Receptores Virais/metabolismo , Receptores CXCR6 , Receptores de Quimiocinas/metabolismo , Síndrome de COVID-19 Pós-Aguda , Ligantes , Convalescença , Receptores Depuradores/metabolismo , Quimiocina CXCL16 , Gravidade do Paciente
4.
Nucleus ; 13(1): 221-235, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36109835

RESUMO

Nuclear lamins and transport are intrinsically linked, but their relationship is yet to be fully unraveled. A multitude of complex, coupled interactions between lamins and nucleoporins (Nups), which mediate active transport into and out of the nucleus, combined with well documented dysregulation of lamins in many cancers, suggests that lamins and nuclear transport may play a pivotal role in carcinogenesis and the preservation of cancer. Changes of function related to lamin/Nup activity can principally lead to DNA damage, further increasing the genetic diversity within a tumor, which could lead to the reduction the effectiveness of antineoplastic treatments. This review discusses and synthesizes different connections of lamins to nuclear transport and offers a number of outlook questions, the answers to which could reveal a new perspective on the connection of lamins to molecular transport of cancer therapeutics, in addition to their established role in nuclear mechanics.


Assuntos
Neoplasias , Complexo de Proteínas Formadoras de Poros Nucleares , Transporte Ativo do Núcleo Celular , Núcleo Celular/metabolismo , Humanos , Laminas/metabolismo , Neoplasias/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo
5.
Immunology ; 166(1): 138-152, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35199335

RESUMO

Intestinal macrophages play a vital role in the maintenance of gut homeostasis through signals derived from the microbiota. We previously demonstrated that microbial-derived metabolites can shape the metabolic functions of macrophages. Here, we show that antibiotic-induced disruption of the intestinal microbiota dramatically alters both the local metabolite environment and the metabolic functions of macrophages in the colon. Broad-spectrum antibiotic administration in mice increased the expression of the large neutral amino acid transporter LAT1 and accordingly, amino acid uptake. Subsequently, antibiotic administration enhanced the metabolic functions of colonic macrophages, increasing phosphorylation of components of mammalian/mechanistic target of rapamycin signalling pathways, with increased expression of genes involved in glycolysis and oxidative phosphorylation (OXPHOS), increased mitochondrial function, increased rate of extracellular acidification (ECAR; measure of glycolysis) and increased rate of oxygen consumption (OCR; measure of OXPHOS). Small bowel macrophages were less metabolically active than their colonic counterparts, with macrophage metabolism in the small intestine being independent of the microbiota. Finally, we reveal tissue-resident Tim4+  CD4+ macrophages exhibit enhanced fatty acid uptake alongside reduced fatty acid synthesis compared to recruited macrophages. Thus, the microbiota shapes gut macrophage metabolism in a compartment-specific manner, with important implications for monocyte recruitment and macrophage differentiation.


Assuntos
Microbioma Gastrointestinal , Macrófagos , Animais , Antibacterianos/farmacologia , Colo , Ácidos Graxos/metabolismo , Macrófagos/metabolismo , Mamíferos , Camundongos
6.
J Surg Res ; 259: 145-153, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33279840

RESUMO

BACKGROUND: In patients with clinical N1 disease, minimally invasive surgery (MIS) has potentially better perioperative outcome compared to open thoracotomy. Additionally, whether adjuvant or neoadjuvant chemotherapy produces the best long-term survival is still debatable. METHODS: We queried The National Cancer Database for patients with clinical N1 NSCLC who underwent surgical resection between 2010 and 2014. Comparison between patients receiving MIS and patients who underwent open thoracotomy was done using an intention-to-treat analysis. Comparison was also done among neoadjuvant, adjuvant chemotherapy, and only surgery. Proportional hazard models were used to evaluate the effects of surgical approach and timing of chemotherapy on overall survival. RESULTS: A total of 1440 and 3942 patients underwent MIS and open thoracotomy respectively. MIS achieved better surgical margins (90.0% versus 88.6%) and shorter length of stay (6.5 ± 6.5 versus 7.3 ± 6.4 d, P ≤ 0.01) compared to open thoracotomy. There were no differences in 30-day and 90-day mortality, nor readmission rates. Neoadjuvant and adjuvant chemotherapy were administered to 13.5% and 57.2% of patients respectively. There was no significant difference in the 5-year overall survival between MIS and open thoracotomy (46% versus 46% P = 0.08). There was significantly better 5-year overall survival in neoadjuvant and adjuvant chemotherapy versus only surgery, but no difference between neoadjuvant and adjuvant chemotherapy (48% versus 47% versus 44%, P < 0.01). CONCLUSIONS: In clinical N1 NSCLC, MIS does not compromise oncological quality or overall survival when compared to open thoracotomy. Overall survival improved in patients treated with chemotherapy but there is no difference when given as neoadjuvant versus adjuvant chemotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Toracotomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Quimioterapia Adjuvante , Bases de Dados Factuais , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade
7.
Front Plant Sci ; 11: 593198, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33193551

RESUMO

Cool season grasses associate asymptomatically with foliar Epichloë endophytic fungi in a symbiosis where Epichloë spp. protects the plant from a number of biotic and abiotic stresses. Furthermore, many grass species can accumulate large quantities of silicon (Si), which also alleviates a similar range of stresses. While Epichloë endophytes may improve uptake of minerals and nutrients, their impact on Si is largely unknown. Likewise, the effect of Si availability on Epichloë colonization remains untested. To assess the bidirectional relationship, we grew tall fescue (Festuca arundinacea) and perennial ryegrass (Lolium perenne) hydroponically with or without Si. Grasses were associated with five different Epichloë endophyte strains [tall fescue: AR584 or wild type (WT); perennial ryegrass: AR37, AR1, or WT] or as Epichloë-free controls. Reciprocally beneficial effects were observed for tall fescue associations. Specifically, Epichloë presence increased Si concentration in the foliage of tall fescue by at least 31%, regardless of endophyte strain. In perennial ryegrass, an increase in foliar Si was observed only for plants associated with the AR37. Epichloë promotion of Si was (i) independent of responses in plant growth, and (ii) positively correlated with endophyte colonization, which lends support to an endophyte effect independent of their impacts on root growth. Moreover, Epichloë colonization in tall fescue increased by more than 60% in the presence of silicon; however, this was not observed in perennial ryegrass. The reciprocal benefits of Epichloë-endophytes and foliar Si accumulation reported here, especially for tall fescue, might further increase grass tolerance to stress.

8.
Pract Neurol ; 20(6): 516, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32546516
9.
Immunology ; 159(1): 26-38, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31777068

RESUMO

Mucosal tissues contain distinct microbial communities that differ drastically depending on the barrier site, and as such, mucosal immune responses have evolved to be tailored specifically for their location. Whether protective or regulatory immune responses against invading pathogens or the commensal microbiota occur is controlled by local mononuclear phagocytes (MNPs). Comprising macrophages and dendritic cells (DCs), the functions of these cells are highly dependent on the local environment. For example, the intestine contains the greatest bacterial load of any site in the body, and hence, intestinal MNPs are hyporesponsive to bacterial stimulation. This is thought to be one of the major mechanisms by which harmful immune responses directed against the trillions of harmless bacteria that line the gut lumen are avoided. Regulation of MNP function by the microbiota has been characterized in the most depth in the intestine but there are several mucosal sites that also contain their own microbiota. In this review, we present an overview of how MNP function is regulated by the microbiota at mucosal sites, highlighting recent novel pathways by which this occurs in the intestine, and new studies elucidating these interactions at mucosal sites that have been characterized in less depth, including the urogenital tract.


Assuntos
Imunidade nas Mucosas , Microbiota/imunologia , Sistema Fagocitário Mononuclear/imunologia , Mucosa/microbiologia , Simbiose/imunologia , Animais , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Tolerância Imunológica , Intestinos/imunologia , Intestinos/microbiologia , Pulmão/microbiologia , Modelos Animais , Boca/imunologia , Boca/microbiologia , Mucosa/imunologia , Sistema Urogenital/imunologia , Sistema Urogenital/microbiologia
10.
PLoS One ; 14(12): e0225021, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31821343

RESUMO

Type 1, or autoimmune, diabetes is caused by the T-cell mediated destruction of the insulin-producing pancreatic beta cells. Non-obese diabetic (NOD) mice spontaneously develop autoimmune diabetes akin to human type 1 diabetes. For this reason, the NOD mouse has been the preeminent murine model for human type 1 diabetes research for several decades. However, humanized mouse models are highly sought after because they offer both the experimental tractability of a mouse model and the clinical relevance of human-based research. Autoimmune T-cell responses against insulin, and its precursor proinsulin, play central roles in the autoimmune responses against pancreatic beta cells in both humans and NOD mice. As a first step towards developing a murine model of the human autoimmune response against pancreatic beta cells we set out to replace the murine insulin 1 gene (Ins1) with the human insulin gene (Ins) using CRISPR/Cas9. Here we describe a NOD mouse strain that expresses human insulin in place of murine insulin 1, referred to as HuPI. HuPI mice express human insulin, and C-peptide, in their serum and pancreata and have normal glucose tolerance. Compared with wild type NOD mice, the incidence of diabetes is much lower in HuPI mice. Only 15-20% of HuPI mice developed diabetes after 300 days, compared to more than 60% of unmodified NOD mice. Immune-cell infiltration into the pancreatic islets of HuPI mice was not detectable at 100 days but was clearly evident by 300 days. This work highlights the feasibility of using CRISPR/Cas9 to create mouse models of human diseases that express proteins pivotal to the human disease. Furthermore, it reveals that even subtle changes in proinsulin protect NOD mice from diabetes.


Assuntos
Diabetes Mellitus Tipo 1/genética , Células Secretoras de Insulina/metabolismo , Insulina/genética , Animais , Sistemas CRISPR-Cas , Diabetes Mellitus Tipo 1/metabolismo , Modelos Animais de Doenças , Humanos , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Pâncreas/metabolismo
11.
Mar Pollut Bull ; 146: 125-133, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426140

RESUMO

We investigated the environmental partitioning and particle characteristics of macro-, meso- and microplastics and their uptake into the mussel, Mytilus edulis. Sediment samples, overlying seawater and mussels from 9 intertidal locations in the South West of England were analysed for abundance and type of microplastic. Micro- and mesoplastic-like particles were found in 88.5% of the 269 mussels sampled, ranging from 1.43 to 7.64 items per mussel. Of these plastic particles, 70.9% were identified as semi-synthetic (mainly modified-cellulose). Mussel microplastic abundance, but not polymer type, was correlated with that of their surrounding sediment, but not with sea-surface microplastic concentration or mussel size for our study sites. We found significant differences in the relative abundance of polymer types and particle sizes between seawater, sediment, and mussels, with mussels over-representing modified-cellulose fibre abundance but under-representing polyvinyl. Mussels contained significantly smaller plastic fragments than their surrounding sediment and shorter fibres than their overlying seawater.


Assuntos
Mytilus edulis/química , Plásticos/análise , Poluentes Químicos da Água/análise , Animais , Ecotoxicologia , Inglaterra , Monitoramento Ambiental , Contaminação de Alimentos/análise , Sedimentos Geológicos/análise , Tamanho da Partícula , Plásticos/química , Plásticos/farmacocinética , Água do Mar/análise , Frutos do Mar/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química , Poluentes Químicos da Água/farmacocinética
12.
Front Immunol ; 9: 2800, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30555479

RESUMO

Diabetogenic T cells infiltrate the pancreatic islets by transmigrating across the microcapillaries residing close to, or within, the pancreatic islets. Deficiency in IFNγ signaling prevents efficient migration of T cells into the pancreatic islets, but the IFNγ-regulated molecules that mediate this are uncertain. Homing of autoreactive T cells into target tissues may require antigen specificity through presentation of cognate antigen by MHC expressed on the vascular endothelium. We investigated the hypothesis that IFNγ promotes the migration of islet antigen-specific CD4+ T cells by upregulating MHC class II on islet endothelial cells (IEC), thereby providing an antigen-specific signal for islet infiltration. Upon IFNγ stimulation, MHC class II, which is not constitutively expressed on IEC, was induced. IFNγ-dependent upregulation of MHC class II was detected in IEC isolated from prediabetic NOD mice at the earliest stages of insulitis, before other markers of inflammation were present. Using a CD4+ T cell-mediated adoptive transfer model of autoimmune diabetes we observed that even though diabetes does not develop in recipient mice lacking IFNγ receptors, mice with MHC class II-deficient IEC were not protected from disease. Thus, IFNγ-regulated molecules, but not MHC class II or antigen presentation by IECs is required for the early migration of antigen-specific CD4+ T cells into the pancreatic islets.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Endoteliais/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Interferon gama/imunologia , Ilhotas Pancreáticas/imunologia , Estado Pré-Diabético/imunologia , Animais , Biomarcadores , Linfócitos T CD4-Positivos/patologia , Células Endoteliais/patologia , Regulação da Expressão Gênica/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Interferon gama/genética , Ilhotas Pancreáticas/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Estado Pré-Diabético/genética , Estado Pré-Diabético/patologia
13.
Sci Transl Med ; 10(464)2018 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-30355800

RESUMO

Macrophages in the healthy intestine are highly specialized and usually respond to the gut microbiota without provoking an inflammatory response. A breakdown in this tolerance leads to inflammatory bowel disease (IBD), but the mechanisms by which intestinal macrophages normally become conditioned to promote microbial tolerance are unclear. Strong epidemiological evidence linking disruption of the gut microbiota by antibiotic use early in life to IBD indicates an important role for the gut microbiota in modulating intestinal immunity. Here, we show that antibiotic use causes intestinal macrophages to become hyperresponsive to bacterial stimulation, producing excess inflammatory cytokines. Re-exposure of antibiotic-treated mice to conventional microbiota induced a long-term, macrophage-dependent increase in inflammatory T helper 1 (TH1) responses in the colon and sustained dysbiosis. The consequences of this dysregulated macrophage activity for T cell function were demonstrated by increased susceptibility to infections requiring TH17 and TH2 responses for clearance (bacterial Citrobacter rodentium and helminth Trichuris muris infections), corresponding with increased inflammation. Short-chain fatty acids (SCFAs) were depleted during antibiotic administration; supplementation of antibiotics with the SCFA butyrate restored the characteristic hyporesponsiveness of intestinal macrophages and prevented T cell dysfunction. Butyrate altered the metabolic behavior of macrophages to increase oxidative phosphorylation and also promoted alternative macrophage activation. In summary, the gut microbiota is essential to maintain macrophage-dependent intestinal immune homeostasis, mediated by SCFA-dependent pathways. Oral antibiotics disrupt this process to promote sustained T cell-mediated dysfunction and increased susceptibility to infections, highlighting important implications of repeated broad-spectrum antibiotic use.


Assuntos
Antibacterianos/farmacologia , Homeostase/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Intestinos/citologia , Macrófagos/metabolismo , Linfócitos T/imunologia , Animais , Butiratos/farmacologia , Citocinas/metabolismo , Ácidos Graxos/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Inflamação/patologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Receptores CCR2/metabolismo , Linfócitos T/efeitos dos fármacos , Células Th1/efeitos dos fármacos
14.
Parkinsonism Relat Disord ; 55: 128-133, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29871791

RESUMO

OBJECTIVE: To describe, and explore heterogeneity in, age at onset/diagnosis in Parkinson's disease (PD) and compare mean age at onset/diagnosis in incidence studies with that in general PD research studies. METHODS: We systematically reviewed studies of PD incidence. We meta-analysed mean age at onset/diagnosis and age-stratum-specific incidence rates. We compared age-specific incidence rates in screening studies in the elderly with whole-population studies. We collated mean ages at onset/diagnosis in clinical studies of PD in five journals July-December 2016. RESULTS: In 17 studies reporting sufficient data to pool, mean age at onset/diagnosis was 69.6 years (95% CI 68.2-71.1), but heterogeneity was high (I2 = 96%). In ten of these studies reporting age at diagnosis specifically, the pooled mean age at diagnosis was slightly higher (71.6 [95% CI 70.6-72.6]) with lower, but still high, heterogeneity (I2 = 84%). In twelve whole-population studies reporting age-specific incidence rates, these peaked in age 70-79 (pooled incidence rate per 100,000 = 93.8 [95% CI 80.3-107.4]). Heterogeneity increased with each increase in age stratum (0% in youngest to 88% in oldest age stratum). Pooled age-specific incidence rates in five population-based screening studies of older age groups were several-fold higher than in whole-population studies. The mean of the reported mean ages at onset/diagnosis in recently published research studies was 60.8 (SD 5.6). CONCLUSION: The mean age of onset/diagnosis PD is about 70, although this may be an underestimate due to under-diagnosis in the elderly. Many published studies use age-unrepresentative subjects: the effect of this selection bias deserves further study.


Assuntos
Envelhecimento , Doença de Parkinson/diagnóstico , Doença de Parkinson/epidemiologia , Distribuição por Idade , Feminino , Humanos , Incidência , Masculino , Doença de Parkinson/terapia , Viés de Seleção
15.
Diabetes ; 66(6): 1650-1660, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28292965

RESUMO

Recent advances in immunotherapeutics have not yet changed the routine management of autoimmune type 1 diabetes. There is an opportunity to repurpose therapeutics used to treat other diseases to treat type 1 diabetes, especially when there is evidence for overlapping mechanisms. Janus kinase (JAK) 1/JAK2 inhibitors are in development or clinical use for indications including rheumatoid arthritis. There is good evidence for activation of the JAK1/JAK2 and signal transducer and activator of transcription (STAT) 1 pathway in human type 1 diabetes and in mouse models, especially in ß-cells. We tested the hypothesis that using these drugs to block the JAK-STAT pathway would prevent autoimmune diabetes. The JAK1/JAK2 inhibitor AZD1480 blocked the effect of cytokines on mouse and human ß-cells by inhibiting MHC class I upregulation. This prevented the direct interaction between CD8+ T cells and ß-cells, and reduced immune cell infiltration into islets. NOD mice treated with AZD1480 were protected from autoimmune diabetes, and diabetes was reversed in newly diagnosed NOD mice. This provides mechanistic groundwork for repurposing clinically approved JAK1/JAK2 inhibitors for type 1 diabetes.


Assuntos
Glicemia/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Diabetes Mellitus Tipo 1/imunologia , Antígenos de Histocompatibilidade Classe II/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Pirazóis/farmacologia , Pirimidinas/farmacologia , Animais , Western Blotting , Linfócitos T CD8-Positivos/imunologia , Quimiocina CXCL10/imunologia , Citocinas/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Citometria de Fluxo , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/imunologia , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 2/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos NOD , Regulação para Cima
16.
Pain Manag ; 6(6): 569-579, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27527577

RESUMO

Postoperative pain is a considerable issue in the Gulf region; however, at present there is a lack of comprehensive guidelines addressing postoperative pain management in the region. Therefore, an expert panel of pain specialists convened to address this issue and a set of key recommendations has been developed pertinent to the practice of postoperative pain management in the Gulf region (Bahrain, Iraq, Kuwait, Oman, Qatar, Saudi Arabia, the United Arab Emirates and Yemen). These recommendations take into consideration the unique variation in cultural, religious and societal beliefs found in the region, as well as varying accessibility to pain medications, thereby aiming to serve as evidence-based guidance on the best practice management of postoperative pain in the Gulf region.


Assuntos
Manejo da Dor/normas , Dor Pós-Operatória/terapia , Consenso , Conferências de Consenso como Assunto , Feminino , Humanos , Masculino , Oriente Médio
17.
Emerg Med J ; 33(6): 438-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27199140

RESUMO

A short cut review was carried out to establish whether prehospital blood transfusion in the trauma patient with active haemorrhage can reduce mortality. 11 directly relevant papers were found using the reported search strategy. Of these two presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these best papers are tabulated. It is concluded that prehospital blood transfusion may reduce short-term mortality in these patients, but that the evidence level is low and further definitive randomised controlled trials are needed to prove benefit.


Assuntos
Transfusão de Sangue , Serviços Médicos de Emergência , Hemorragia/terapia , Cuidados para Prolongar a Vida , Medicina de Emergência Baseada em Evidências , Hemorragia/mortalidade , Humanos
18.
J Neurophysiol ; 115(3): 1446-57, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26763775

RESUMO

Locomotor control requires functional flexibility to support an animal's full behavioral repertoire. This flexibility is partly endowed by neuromodulators, allowing neural networks to generate a range of motor output configurations. In hatchling Xenopus tadpoles, before the onset of free-swimming behavior, the gaseous modulator nitric oxide (NO) inhibits locomotor output, shortening swim episodes and decreasing swim cycle frequency. While populations of nitrergic neurons are already present in the tadpole's brain stem at hatching, neurons positive for the NO-synthetic enzyme, NO synthase, subsequently appear in the spinal cord, suggesting additional as yet unidentified roles for NO during larval development. Here, we first describe the expression of locomotor behavior during the animal's change from an early sessile to a later free-swimming lifestyle and then compare the effects of NO throughout tadpole development. We identify a discrete switch in nitrergic modulation from net inhibition to overall excitation, coincident with the transition to free-swimming locomotion. Additionally, we show in isolated brain stem-spinal cord preparations of older larvae that NO's excitatory effects are manifested as an increase in the probability of spontaneous swim episode occurrence, as found previously for the neurotransmitter dopamine, but that these effects are mediated within the brain stem. Moreover, while the effects of NO and dopamine are similar, the two modulators act in parallel rather than NO operating serially by modulating dopaminergic signaling. Finally, NO's activation of neurons in the brain stem also leads to the release of NO in the spinal cord that subsequently contributes to NO's facilitation of swimming.


Assuntos
Tronco Encefálico/crescimento & desenvolvimento , Óxido Nítrico/metabolismo , Natação , Animais , Tronco Encefálico/metabolismo , Tronco Encefálico/fisiologia , Dopamina/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Larva/fisiologia , Inibição Neural , Periodicidade , Medula Espinal/crescimento & desenvolvimento , Medula Espinal/metabolismo , Medula Espinal/fisiologia , Xenopus
19.
Eur J Immunol ; 45(9): 2494-503, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25959978

RESUMO

Type 1 diabetes results from destruction of pancreatic beta cells by autoreactive T cells. Both CD4(+) and CD8(+) T cells have been shown to mediate beta-cell killing. While CD8(+) T cells can directly recognize MHC class I on beta cells, the interaction between CD4(+) T cells and beta cells remains unclear. Genetic association studies have strongly implicated HLA-DQ alleles in human type 1 diabetes. Here we studied MHC class II expression on beta cells in nonobese diabetic mice that were induced to develop diabetes by diabetogenic CD4(+) T cells with T-cell receptors that recognize beta-cell antigens. Acute infiltration of CD4(+) T cells in islets occurred with rapid onset of diabetes. Beta cells from islets with immune infiltration expressed MHC class II mRNA and protein. Exposure of beta cells to IFN-γ increased MHC class II gene expression, and blocking IFN-γ signaling in beta cells inhibited MHC class II upregulation. IFN-γ also increased HLA-DR expression in human islets. MHC class II(+) beta cells stimulated the proliferation of beta-cell-specific CD4(+) T cells. Our study indicates that MHC class II molecules may play an important role in beta-cell interaction with CD4(+) T cells in the development of type 1 diabetes.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Antígenos HLA-DQ/imunologia , Antígenos HLA-DR/imunologia , Células Secretoras de Insulina/imunologia , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Comunicação Celular/imunologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citotoxicidade Imunológica , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patologia , Feminino , Regulação da Expressão Gênica , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/patologia , Interferon gama/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos NOD , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Técnicas de Cultura de Tecidos
20.
Diabetologia ; 58(1): 140-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25301392

RESUMO

AIMS/HYPOTHESIS: Type 1 diabetes results from T cell-mediated destruction of pancreatic beta cells. The mechanisms of beta cell destruction in vivo, however, remain unclear. We aimed to test the relative roles of the main cell death pathways: apoptosis, necrosis and necroptosis, in beta cell death in the development of CD4(+) T cell-mediated autoimmune diabetes. METHODS: We altered expression levels of critical cell death proteins in mouse islets and tested their ability to survive CD4(+) T cell-mediated attack using an in vivo graft model. RESULTS: Loss of the B cell leukaemia/lymphoma 2 (BCL-2) homology domain 3-only proteins BIM, PUMA or BID did not protect beta cells from this death. Overexpression of the anti-apoptotic protein BCL-2 or combined deficiency of the pro-apoptotic multi-BCL2 homology domain proteins BAX and BAK also failed to prevent beta cell destruction. Furthermore, loss of function of the death receptor Fas or its essential downstream signalling molecule Fas-associated death domain (FADD) in islets was also not protective. Using electron microscopy we observed that dying beta cells showed features of necrosis. However, islets deficient in receptor-interacting serine/threonine protein kinase 3 (RIPK3), a critical initiator of necroptosis, were still normally susceptible to CD4(+) T cell-mediated destruction. Remarkably, simultaneous inhibition of apoptosis and necroptosis by combining loss of RIPK3 and overexpression of BCL-2 in islets did not protect them against immune attack either. CONCLUSIONS/INTERPRETATION: Collectively, our data indicate that beta cells die by necrosis in autoimmune diabetes and that the programmed cell death pathways apoptosis and necroptosis are both dispensable for this process.


Assuntos
Autoimunidade/fisiologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/patologia , Linfócitos T/imunologia , Animais , Apoptose/genética , Apoptose/fisiologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Rejeição de Enxerto/genética , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/metabolismo , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Necrose/genética , Necrose/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/fisiologia , Receptores de Morte Celular/genética , Receptores de Morte Celular/fisiologia
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