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1.
Opt Express ; 32(11): 18761-18770, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38859026

RESUMEN

The recent advent of quantum computing has the potential to overhaul security, communications, and scientific modeling. Superconducting qubits are a leading platform that is advancing noise-tolerant intermediate-scale quantum processors. The implementation requires scaling to large numbers of superconducting qubits, circuit depths, and gate speeds, wherein high-purity RF signal generation and effective cabling transport are desirable. Fiber photonic-enhanced RF signal generation has demonstrated the principle of addressing both signal generation and transport requirements, supporting intermediate qubit numbers and robust packaging efforts; however, fiber-based approaches to RF signal distribution are often bounded by their phase instability. Here, we present a silicon photonic integrated circuit-based version of a photonic-enhanced RF signal generator that demonstrates the requisite stability, as well as a path towards the necessary signal fidelity.

2.
Sci Total Environ ; 893: 164658, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37321511

RESUMEN

As motivation to address environmental dissemination of antimicrobial resistance (AMR) is mounting, there is a need to characterize mechanisms by which AMR can propagate under environmental conditions. Here we investigated the effect of temperature and stagnation on the persistence of wastewater-associated antibiotic resistance markers in riverine biofilms and the invasion success of genetically-tagged Escherichia coli. Biofilms grown on glass slides incubated in-situ downstream of a wastewater treatment plant effluent discharge point were transferred to laboratory-scale flumes fed with filtered river water under potentially stressful temperature and flow conditions: recirculation flow at 20 °C, stagnation at 20 °C, and stagnation at 30 °C. After 14 days, quantitative PCR and amplicon sequencing were used to quantify bacteria, biofilms diversity, resistance markers (sul1, sul2, ermB, tetW, tetM, tetB, blaCTX-M-1, intI1) and E. coli. Resistance markers significantly decreased over time regardless of the treatment applied. Although invading E. coli were initially able to colonize the biofilms, its abundance subsequently declined. Stagnation was associated with a shift in biofilm taxonomic composition, but there was no apparent effect of flow conditions or the simulated river-pool warming (30 °C) on AMR persistence or invasion success of E. coli. Results however indicated that antibiotic resistance markers in the riverine biofilms decreased under the experimental conditions in the absence of exposure to external inputs of antibiotics and AMR.


Asunto(s)
Biopelículas , Farmacorresistencia Microbiana , Escherichia coli , Genes Bacterianos , Antibacterianos/farmacología , Escherichia coli/genética , Calor
3.
Ann Oncol ; 33(11): 1186-1199, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35988656

RESUMEN

BACKGROUND: Germline variant evaluation in precision oncology opens new paths toward the identification of patients with genetic tumor risk syndromes and the exploration of therapeutic relevance. Here, we present the results of germline variant analysis and their clinical implications in a precision oncology study for patients with predominantly rare cancers. PATIENTS AND METHODS: Matched tumor and control genome/exome and RNA sequencing was carried out for 1485 patients with rare cancers (79%) and/or young adults (77% younger than 51 years) in the National Center for Tumor Diseases/German Cancer Consortium (NCT/DKTK) Molecularly Aided Stratification for Tumor Eradication Research (MASTER) trial, a German multicenter, prospective, observational precision oncology study. Clinical and therapeutic relevance of prospective pathogenic germline variant (PGV) evaluation was analyzed and compared to other precision oncology studies. RESULTS: Ten percent of patients (n = 157) harbored PGVs in 35 genes associated with autosomal dominant cancer predisposition, whereof up to 75% were unknown before study participation. Another 5% of patients (n = 75) were heterozygous carriers for recessive genetic tumor risk syndromes. Particularly, high PGV yields were found in patients with gastrointestinal stromal tumors (GISTs) (28%, n = 11/40), and more specifically in wild-type GISTs (50%, n = 10/20), leiomyosarcomas (21%, n = 19/89), and hepatopancreaticobiliary cancers (16%, n = 16/97). Forty-five percent of PGVs (n = 100/221) supported treatment recommendations, and its implementation led to a clinical benefit in 40% of patients (n = 10/25). A comparison of different precision oncology studies revealed variable PGV yields and considerable differences in germline variant analysis workflows. We therefore propose a detailed workflow for germline variant evaluation. CONCLUSIONS: Genetic germline testing in patients with rare cancers can identify the very first patient in a hereditary cancer family and can lead to clinical benefit in a broad range of entities. Its routine implementation in precision oncology accompanied by the harmonization of germline variant evaluation workflows will increase clinical benefit and boost research.


Asunto(s)
Neoplasias , Adulto Joven , Humanos , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/terapia , Mutación de Línea Germinal , Predisposición Genética a la Enfermedad , Estudios Prospectivos , Síndrome , Medicina de Precisión/métodos
4.
Aerosol Sci Technol ; 56(12): 1146-1155, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-38075547

RESUMEN

Numerous variants of SARS-CoV-2 with increased transmissibility have emerged over the course of the pandemic. Potential explanations for the increased transmissibility of these variants include increased shedding from infected individuals, increased environmental stability, and/or a lower infectious dose. Upon exhalation of a respiratory particle into the environment, water present in the particle is rapidly lost through evaporation, resulting in a decrease in particle size. The aim of the present study was to compare the losses of infectivity of different isolates of SARS-CoV-2 during the rapid evaporation of aerosol particles that occurs immediately post-generation to assess if there are differences suggestive of increased survival, and ultimately greater transmissibility, for more recent variants. Losses of infectivity of several isolates of SARS-CoV-2 suspended in viral culture media were assessed following aerosolization and evaporation in a flowing chamber. The results demonstrate that losses of infectivity measured post-evaporation were similar for three different isolates of SARS-CoV-2, including isolates from the more recent Delta and Omicron lineages. The average loss in infectivity across all three isolates was 61 ± 15% (-0.46 ± 0.17 log10 TCID50/L-air) at a relative humidity <30%. These results, together with those from several previous studies, suggest that it is unlikely that an increase in environmental stability contributes to the observed increases in transmissibility observed with more recent variants of SARS-CoV-2.

5.
Environ Pollut ; 265(Pt A): 114695, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32806416

RESUMEN

Mining causes extensive damage to aquatic ecosystems via acidification, heavy metal pollution, sediment loading, and Ca decline. Yet little is known about the effects of mining on freshwater systems in the Southern Hemisphere. A case in point is the region of western Tasmania, Australia, an area extensively mined in the 19th century, resulting in severe environmental contamination. In order to assess the impacts of mining on aquatic ecosystems in this region, we present a multiproxy investigation of the lacustrine sediments from Owen Tarn, Tasmania. This study includes a combination of radiometric dating (14C and 210Pb), sediment geochemistry (XRF and ICP-MS), pollen, charcoal and diatoms. Generalised additive mixed models were used to test if changes in the aquatic ecosystem can be explained by other covariates. Results from this record found four key impact phases: (1) Pre-mining, (2) Early mining, (3) Intense mining, and (4) Post-mining. Before mining, low heavy metal concentrations, slow sedimentation, low fire activity, and high biomass indicate pre-impact conditions. The aquatic environment at this time was oligotrophic and dystrophic with sufficient light availability, typical of western Tasmanian lakes during the Holocene. Prosperous mining resulted in increased burning, a decrease in landscape biomass and an increase in sedimentation resulting in decreased light availability of the aquatic environment. Extensive mining at Mount Lyell in the 1930s resulted in peak heavy metal pollutants (Pb, Cu and Co) and a further increase in inorganic inputs resulted in a disturbed low light lake environment (dominated by Hantzschia amphioxys and Pinnularia divergentissima). Following the closure of the Mount Lyell Co. in 1994 CE, Ca declined to below pre-mining levels resulting in a new diatom assemblage and deformed diatom valves. Therefore, the Owen Tarn record demonstrates severe sediment pollution and continued impacts of mining long after mining has stopped at Mt. Lyell Mining Co.


Asunto(s)
Ecosistema , Contaminantes Químicos del Agua/análisis , Australia , Calcio , Monitoreo del Ambiente , Sedimentos Geológicos , Tasmania
6.
EJNMMI Phys ; 7(1): 47, 2020 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-32666231

RESUMEN

An amendment to this paper has been published and can be accessed via the original article.

7.
EJNMMI Phys ; 7(1): 24, 2020 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-32372135

RESUMEN

BACKGROUND: Despite the advent of clinical PET-MR imaging for routine use in 2011 and the development of several methods to address the problem of attenuation correction, some challenges remain. We have identified and investigated several issues that might affect the reliability and accuracy of current attenuation correction methods when these are implemented for clinical and research studies of the brain. These are (1) the accuracy of converting CT Hounsfield units, obtained from an independently acquired CT scan, to 511 keV linear attenuation coefficients; (2) the effect of padding used in the MR head coil; (3) the presence of close-packed hair; (4) the effect of headphones. For each of these, we have examined the effect on reconstructed PET images and evaluated practical mitigating measures. RESULTS: Our major findings were (1) for both Siemens and GE PET-MR systems, CT data from either a Siemens or a GE PET-CT scanner may be used, provided the conversion to 511 keV µ-map is performed by the PET-MR vendor's own method, as implemented on their PET-CT scanner; (2) the effect of the head coil pads is minimal; (3) the effect of dense hair in the field of view is marked (> 10% error in reconstructed PET images); and (4) using headphones and not including them in the attenuation map causes significant errors in reconstructed PET images, but the risk of scanning without them may be acceptable following sound level measurements. CONCLUSIONS: It is important that the limitations of attenuation correction in PET-MR are considered when designing research and clinical PET-MR protocols in order to enable accurate quantification of brain PET scans. Whilst the effect of pads is not significant, dense hair, the use of headphones and the use of an independently acquired CT-scan can all lead to non-negligible effects on PET quantification. Although seemingly trivial, these effects add complications to setting up protocols for clinical and research PET-MR studies that do not occur with PET-CT. In the absence of more sophisticated PET-MR brain attenuation correction, the effect of all of the issues above can be minimised if the pragmatic approaches presented in this work are followed.

8.
Nat Commun ; 10(1): 5464, 2019 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-31784527

RESUMEN

The field of quantum computing has grown from concept to demonstration devices over the past 20 years. Universal quantum computing offers efficiency in approaching problems of scientific and commercial interest, such as factoring large numbers, searching databases, simulating intractable models from quantum physics, and optimizing complex cost functions. Here, we present an 11-qubit fully-connected, programmable quantum computer in a trapped ion system composed of 13 171Yb+ ions. We demonstrate average single-qubit gate fidelities of 99.5[Formula: see text], average two-qubit-gate fidelities of 97.5[Formula: see text], and SPAM errors of 0.7[Formula: see text]. To illustrate the capabilities of this universal platform and provide a basis for comparison with similarly-sized devices, we compile the Bernstein-Vazirani and Hidden Shift algorithms into our native gates and execute them on the hardware with average success rates of 78[Formula: see text] and 35[Formula: see text], respectively. These algorithms serve as excellent benchmarks for any type of quantum hardware, and show that our system outperforms all other currently available hardware.

9.
J Neonatal Perinatal Med ; 12(1): 41-45, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30400108

RESUMEN

OBJECTIVES: To evaluate the characteristics and comorbidities associated with ROP in micro-premature infants and their results. METHODS: This is a retrospective chart review involving multiple intensive care units in Central Texas from 2011 to 2016. Infants were included if birth weight (BW) was≤750 g with confirmed ROP by the International Classification of Retinopathy of Prematurity (ICROP). Neonates were examined and treated with laser ablation or intravitreal ranibizumab (IVR) with subsequent laser treatment, guided by fluorescein angiography, if met treatment criteria defined as type 1 ROP by the Early Treatment of Retinopathy of Prematurity standards. Time to regression was defined clinically. Results were analyzed using chi-squared test. RESULTS: 100 neonates were included in the study. Mean BW was 599 grams and mean gestational age was 24.2 weeks. Forty neonates were classified as type 1 ROP and therefore required intervention; of them 21 received laser alone and 19 required IVR with subsequent laser. Only 2 patients received more than one IVR injection. None of the patients progressed to stage 4 or 5 ROP. CONCLUSIONS: Despite such low birth weights, none of these neonates progressed to stage 4 or 5 ROP likely because of prompt examination and treatment with laser or with IVR and subsequent laser. IVR might serve as a bridge to laser in type 1 ROP allowing some retinal vessel development prior to definitive laser treatment.


Asunto(s)
Recien Nacido con Peso al Nacer Extremadamente Bajo , Enfermedades del Prematuro/fisiopatología , Recien Nacido Prematuro , Retinopatía de la Prematuridad/fisiopatología , Inhibidores de la Angiogénesis/administración & dosificación , Comorbilidad , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido , Enfermedades del Prematuro/terapia , Inyecciones Intravítreas , Coagulación con Láser , Masculino , Ranibizumab/administración & dosificación , Retinopatía de la Prematuridad/diagnóstico , Retinopatía de la Prematuridad/terapia , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Texas , Resultado del Tratamiento
10.
PLoS One ; 13(11): e0207259, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30440008

RESUMEN

BACKGROUND: Smallpox vaccinations were stopped globally in 1980. Recent studies have shown that in women, being smallpox vaccinated was associated with a reduced risk of HIV infection compared with not being smallpox vaccinated. At the initial infection, HIV-1 most often uses CCR5 as a co-receptor to infect the T-lymphocytes. We therefore investigated whether smallpox vaccination is associated with a down-regulation of CCR5 on the surface of peripheral T-lymphocytes in healthy women in Guinea-Bissau. METHODS: We included HIV seronegative women from Bissau, Guinea-Bissau, born before 1974, with and without a smallpox vaccination scar. Blood samples were stabilised in a TransFix buffer solution and stained for flow cytometry according to a T-cell maturation profile. RESULTS: Ninety-seven women were included in the study; 52 with a smallpox vaccination scar and 45 without a scar. No association between smallpox vaccination scar and CCR5 expression was found in any T-lymphocyte subtype. CONCLUSION: Among HIV seronegative women, being smallpox vaccinated more than 40 years ago was not associated with a down-regulation of CCR5 receptors on the surface of peripheral T-lymphocytes.


Asunto(s)
Receptores CCR5/metabolismo , Viruela/inmunología , Viruela/prevención & control , Linfocitos T/inmunología , Vacunación , Estudios de Casos y Controles , Femenino , Regulación de la Expresión Génica , Infecciones por VIH/inmunología , Infecciones por VIH/prevención & control , VIH-1 , Humanos , Persona de Mediana Edad
11.
Neurogastroenterol Motil ; 30(6): e13300, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29377328

RESUMEN

BACKGROUND: Regulation of gastrointestinal motility involves excitatory and inhibitory neurotransmission. Nitric oxide (NO), the major inhibitory neurotransmitter, acts via its receptor NO-sensitive guanylyl cyclase (NO-GC). In the GI tract, NO-GC is expressed in several cell types such as smooth muscle cells (SMC) and interstitial cells of Cajal (ICC). Using cell-specific knockout mice, we have previously shown that NO-GC modulates spontaneous contractions in colonic longitudinal smooth muscle. However, its detailed role in the colonic circular smooth muscle is still unclear. METHODS: Myography was performed to evaluate spontaneous contractions in rings of proximal colon (2.5 mm) from global (GCKO) and cell-specific knockout mice for NO-GC. Immunohistochemistry and in situ hybridization were used to specify NO-GC expression. KEY RESULTS: Colonic circular smooth muscle showed three different contraction patterns: high-frequency ripples, slow phasic contractions, and large contractions. Ripples formed independently of NO-GC. Slow phasic contractions occurred intermittently in WT, SMC-GCKO, and ICC-GCKO tissue, whereas they were more prominent and prolonged in GCKO and SMC/ICC-GCKO tissue. Tetrodotoxin and the NO-GC inhibitor ODQ transformed slow phasic contractions of WT and single cell-specific knockout into GCKO-like contractions. ODQ increased the frequency of large contractions in WT and ICC-GCKO colon but not in GCKO, SMC-GCKO, and SMC/ICC-GCKO preparations. Tetrodotoxin and hexamethonium abolished large contractions. CONCLUSIONS AND INFERENCES: We conclude that short rings of murine colon can be effectively used to record spontaneous contractions. Although NO-GC in SMC determines smooth muscle tone, concerted action of NO-GC in both SMC and ICC modulates slow phasic contractions and large contractions.


Asunto(s)
Colon/fisiología , Células Intersticiales de Cajal/fisiología , Contracción Muscular/fisiología , Músculo Liso/fisiología , Miocitos del Músculo Liso/fisiología , Guanilil Ciclasa Soluble/fisiología , Animales , Colon/citología , Femenino , Motilidad Gastrointestinal/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Óxido Nítrico/fisiología , Técnicas de Cultivo de Órganos , Transducción de Señal/fisiología
12.
Eur J Nutr ; 57(4): 1421-1433, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28378296

RESUMEN

PURPOSE: To investigate associations between dietary patterns, socio-demographic factors and anthropometric measurements in adult New Zealanders. METHODS: Dietary patterns were identified using factor analysis in adults 15 years plus (n = 4657) using 24-h diet recall data from the 2008/09 New Zealand Adult Nutrition Survey. Multivariate regression was used to investigate associations between dietary patterns and age, gender and ethnicity. After controlling for demographic factors, associations between dietary patterns and food insecurity, deprivation, education, and smoking were investigated. Associations between dietary patterns and body mass index and waist circumference were examined adjusting for demographic factors, smoking and energy intake. RESULTS: Two dietary patterns were identified. 'Healthy' was characterised by breakfast cereal, low fat milk, soy and rice milk, soup and stock, yoghurt, bananas, apples, other fruit and tea, and low intakes of pies and pastries, potato chips, white bread, takeaway foods, soft drinks, beer and wine. 'Traditional' was characterised by beef, starchy vegetables, green vegetables, carrots, tomatoes, savoury sauces, regular milk, cream, sugar, tea and coffee, and was low in takeaway foods. The 'healthy' pattern was positively associated with age, female gender, New Zealand European or other ethnicity, and a secondary school qualification, and inversely associated with smoking, food insecurity, area deprivation, BMI and waist circumference. The 'traditional' pattern was positively associated with age, male gender, smoking, food insecurity and inversely associated with a secondary school qualification. CONCLUSIONS: A 'Healthy' dietary pattern was associated with higher socio-economic status and reduced adiposity, while the 'traditional' pattern was associated with lower socio-economic status.


Asunto(s)
Antropometría , Dieta , Encuestas Nutricionales , Adolescente , Adulto , Anciano , Índice de Masa Corporal , Estudios Transversales , Demografía , Conducta Alimentaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nueva Zelanda , Embarazo , Factores Socioeconómicos , Verduras , Adulto Joven
13.
Artículo en Inglés | MEDLINE | ID: mdl-28782271

RESUMEN

BACKGROUND: Gastrointestinal (GI) motility originates from coordinated movements of circular (CM) and longitudinal (LM) smooth muscle. How the two muscle layers react individually to nitrergic input and how they integrate nitrergic signaling is not thoroughly understood. METHODS: We used immunohistochemistry to unveil expression of NO-sensitive guanylyl cyclase (NO-GC) in the ileum. For functional analyses, we measured tone of ileal CM and spontaneous contractions in both ileal muscle layers from mice lacking NO-GC globally (GCKO) and specifically in smooth muscle cells (SMC-GCKO). KEY RESULTS: In contrast to other parts of the GI tract, NO-GC was not expressed in ckit-positive cells in ileum. NO-GC expression was intense in platelet-derived growth factor receptor α-positive cells and in yet unidentified cells of myenteric plexus and serosa. Both CM and LM developed spontaneous contractile activity; frequency and duration of their spontaneous contractions were identical. The amplitude of spontaneous contractions in CM was increased in the absence of NO-GC. In ileum from control (ctrl) animals, inhibition of NO-GC increased whereas NO-GC stimulation decreased tissue tone. In contrast, contractile activity in LM was not different between ctrl and knockout strains. Here, NO led to suppression of spontaneous contractions of ctrl ileum whereas GCKO tissue was unaffected. To our surprise, NO suppressed spontaneous contractions in SMC-GCKO ileum indicating participation of other cell type(s). CONCLUSIONS AND INFERENCES: NO-GC in SMC is involved in the regulation of tone and amplitude of spontaneous contractions in ileal CM. In LM, NO induces suppression of spontaneous contractions via NO-GC in a non-SMC type.


Asunto(s)
Motilidad Gastrointestinal , Guanilato Ciclasa/metabolismo , Íleon/metabolismo , Músculo Liso/metabolismo , Óxido Nítrico/metabolismo , Animales , Femenino , Guanilato Ciclasa/genética , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Contracción Muscular , Transducción de Señal
14.
Acta Psychiatr Scand ; 137(1): 39-46, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29072776

RESUMEN

OBJECTIVE: Treatment resistance is a challenge for the management of schizophrenia. It is not always clear whether inadequate response is secondary to medication ineffectiveness, as opposed to medication underexposure due to non-adherence or pharmacokinetic factors. We investigated the prevalence of subtherapeutic antipsychotic plasma levels in patients identified as treatment-resistant by their treating clinician. METHOD: Between January 2012 and April 2017, antipsychotic plasma levels were measured in 99 individuals provisionally diagnosed with treatment-resistant schizophrenia by their treating clinicians, but not prescribed clozapine. Patients were followed up to determine whether they were subsequently admitted to hospital. RESULTS: Thirty-five per cent of plasma levels were subtherapeutic, and of these, 34% were undetectable. Black ethnicity (P = 0.006) and lower dose (P < 0.001) were significantly associated with subtherapeutic/undetectable plasma levels. Individuals with subtherapeutic/undetectable levels were significantly more likely to be admitted to hospital (P = 0.02). CONCLUSION: A significant proportion of patients considered treatment-resistant have subtherapeutic antipsychotic plasma levels, and this is associated with subsequent admission. The presence of subtherapeutic plasma levels may suggest a need to address adherence or pharmacokinetic factors as opposed to commencing clozapine treatment. While antipsychotic levels are not recommended for the routine adjustment of dosing, they may assist with the assessment of potential treatment resistance in schizophrenia.


Asunto(s)
Antipsicóticos/uso terapéutico , Trastornos Psicóticos/tratamiento farmacológico , Esquizofrenia/tratamiento farmacológico , Adulto , Negro o Afroamericano , Anciano , Antipsicóticos/sangre , Relación Dosis-Respuesta a Droga , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Farmacocinética , Insuficiencia del Tratamiento , Resultado del Tratamiento , Población Blanca , Adulto Joven
15.
Clin Exp Immunol ; 183(2): 206-20, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26422112

RESUMEN

In 40% of cases of classical Hodgkin lymphoma (cHL), Epstein-Barr virus (EBV) latency-II antigens [EBV nuclear antigen 1 (EBNA1)/latent membrane protein (LMP)1/LMP2A] are present (EBV(+) cHL) in the malignant cells and antigen presentation is intact. Previous studies have shown consistently that HLA-A*02 is protective in EBV(+) cHL, yet its role in disease pathogenesis is unknown. To explore the basis for this observation, gene expression was assessed in 33 cHL nodes. Interestingly, CD8 and LMP2A expression were correlated strongly and, for a given LMP2A level, CD8 was elevated markedly in HLA-A*02(-) versus HLA-A*02(+) EBV(+) cHL patients, suggesting that LMP2A-specific CD8(+) T cell anti-tumoral immunity may be relatively ineffective in HLA-A*02(-) EBV(+) cHL. To ascertain the impact of HLA class I on EBV latency antigen-specific immunodominance, we used a stepwise functional T cell approach. In newly diagnosed EBV(+) cHL, the magnitude of ex-vivo LMP1/2A-specific CD8(+) T cell responses was elevated in HLA-A*02(+) patients. Furthermore, in a controlled in-vitro assay, LMP2A-specific CD8(+) T cells from healthy HLA-A*02 heterozygotes expanded to a greater extent with HLA-A*02-restricted compared to non-HLA-A*02-restricted cell lines. In an extensive analysis of HLA class I-restricted immunity, immunodominant EBNA3A/3B/3C-specific CD8(+) T cell responses were stimulated by numerous HLA class I molecules, whereas the subdominant LMP1/2A-specific responses were confined largely to HLA-A*02. Our results demonstrate that HLA-A*02 mediates a modest, but none the less stronger, EBV-specific CD8(+) T cell response than non-HLA-A*02 alleles, an effect confined to EBV latency-II antigens. Thus, the protective effect of HLA-A*02 against EBV(+) cHL is not a surrogate association, but reflects the impact of HLA class I on EBV latency-II antigen-specific CD8(+) T cell hierarchies.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Antígeno HLA-A2/inmunología , Herpesvirus Humano 4/inmunología , Herpesvirus Humano 4/aislamiento & purificación , Enfermedad de Hodgkin/inmunología , Enfermedad de Hodgkin/virología , Proteínas de la Matriz Viral/inmunología , Adolescente , Adulto , Anciano , Presentación de Antígeno , Linfocitos T CD8-positivos/virología , Femenino , Genes MHC Clase I , Antígeno HLA-A2/genética , Herpesvirus Humano 4/genética , Enfermedad de Hodgkin/genética , Enfermedad de Hodgkin/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Proteínas de la Matriz Viral/genética , Adulto Joven
16.
Psychopharmacology (Berl) ; 233(9): 1605-21, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26667479

RESUMEN

RATIONALE: Autoantibodies to central nervous system (CNS) neuronal surface antigens have been described in association with autoimmune encephalopathies which prominently feature psychiatric symptoms in addition to neurological symptoms. The potential role of these autoantibodies in primary psychiatric diseases such as schizophrenia or bipolar affective disorder is of increasing interest. OBJECTIVES: We aimed to review the nature of psychiatric symptoms associated with neuronal surface autoantibodies, in the context of autoimmune encephalopathies as well as primary psychiatric disorders, and to review the mechanisms of action of these autoantibodies from a psychopharmacological perspective. RESULTS: The functional effects of the autoantibodies on their target antigens are described; their clinical expression is at least in part mediated by their effects on neuronal receptor function, primarily at the synapse, usually resulting in receptor hypofunction. The psychiatric effects of the antibodies are related to known functions of the receptor target or its complexed proteins, with reference to supportive genetic and pharmacological evidence where relevant. Evidence for a causal role of these autoantibodies in primary psychiatric disease is increasing but remains controversial; relevant methodological controversies are outlined. Non-receptor-based mechanisms of autoantibody action, including neuroinflammatory mechanisms, and therapeutic implications are discussed. CONCLUSIONS: An analysis of the autoantibodies from a psychopharmacological perspective, as endogenous, bioactive, highly specific, receptor-targeting molecules, provides a valuable opportunity to understand the neurobiological basis of associated psychiatric symptoms. Potentially, new treatment strategies will emerge from the improving understanding of antibody-antigen interaction within the CNS.


Asunto(s)
Antígenos de Superficie/inmunología , Autoanticuerpos/inmunología , Sistema Nervioso Central/inmunología , Trastornos Mentales/inmunología , Trastornos Mentales/psicología , Neuronas/inmunología , Psicofarmacología , Animales , Humanos , Receptores de N-Metil-D-Aspartato/inmunología
17.
Clin Exp Immunol ; 179(1): 100-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25112375

RESUMEN

CD8 T cells specific for islet autoantigens are major effectors of ß cell damage in type 1 diabetes, and measurement of their number and functional characteristics in blood represent potentially important disease biomarkers. CD8 T cell reactivity against glutamic acid decarboxylase 65 (GAD65) in HLA-A*0201 subjects has been reported to focus on an immunogenic region 114-123 (VMNILLQYVV), with studies demonstrating both 114-123 and 114-122 epitopes being targeted. However, the fine specificity of this response is unclear and the key question as to which epitope(s) ß cells naturally process and present and, therefore, the pathogenic potential of CD8 T cells with different specificities within this region has not been addressed. We generated human leucocyte antigen (HLA)-A*0201-restricted CD8 T cell clones recognizing either 114-122 alone or both 114-122 and 114-123. Both clone types show potent and comparable effector functions (cytokine and chemokine secretion) and killing of indicator target cells externally pulsed with cognate peptide. However, only clones recognizing 114-123 kill target cells transfected with HLA-A*0201 and GAD2 and HLA-A*0201(+) human islet cells. We conclude that the endogenous pathway of antigen processing by HLA-A*0201-expressing cells generates GAD65114-123 as the predominant epitope in this region. These studies highlight the importance of understanding ß cell epitope presentation in the design of immune monitoring for potentially pathogenic CD8 T cells.


Asunto(s)
Presentación de Antígeno/inmunología , Glutamato Descarboxilasa/inmunología , Islotes Pancreáticos/inmunología , Linfocitos T Citotóxicos/inmunología , Autoantígenos/inmunología , Línea Celular , Células Clonales , Epítopos de Linfocito T/inmunología , Glutamato Descarboxilasa/química , Antígeno HLA-A2/inmunología , Humanos , Activación de Linfocitos/inmunología
18.
J Sci Med Sport ; 18(2): 230-5, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24709362

RESUMEN

OBJECTIVES: There is increasing evidence that select forms of exercise are associated with vascular changes that are in opposition to the well-accepted beneficial effects of moderate intensity aerobic exercise. To determine if alterations in arterial stiffness occur following eccentrically accentuated aerobic exercise, and if changes are associated with measures of muscle soreness. DESIGN: Repeated measures experimental cohort. METHODS: Twelve (m=8/f=4) moderately trained (VO2max=52.2 ± 7.4 ml kg(-1)min(-1)) participants performed a downhill run at -12° grade using a speed that elicited 60% VO2max for 40 min. Cardiovascular and muscle soreness measures were collected at baseline and up to 72 h post-running. RESULTS: Muscle soreness peaked at 48 h (p=<0.001). Arterial stiffness similarly peaked at 48 h (p=0.04) and remained significantly elevated above baseline through 72 h. CONCLUSIONS: Eccentrically accentuated downhill running is associated with arterial stiffening in the absence of an extremely prolonged duration or fast pace. The timing of alterations coincides with the well-documented inflammatory response that occurs from the muscular insult of downhill running, but whether the observed changes are a result of either systemic or local inflammation is yet unclear. These findings may help to explain evidence of arterial stiffening in long-term runners and following prolonged duration races wherein cumulative eccentric loading is high.


Asunto(s)
Ejercicio Físico/fisiología , Mialgia/etiología , Carrera/fisiología , Rigidez Vascular , Adulto , Estudios de Cohortes , Femenino , Voluntarios Sanos , Humanos , Masculino , Análisis de la Onda del Pulso , Adulto Joven
19.
Acta Psychiatr Scand ; 130(6): 427-38, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25201058

RESUMEN

OBJECTIVE: To describe a practical approach to the community management of treatment-resistant schizophrenia (TRS). METHOD: A descriptive review of an approach to the assessment and management of patients with TRS, including the community titration of clozapine treatment, and a report of the management recommendations for the first one hundred patients assessed by the Treatment REview and Assessment Team (TREAT). RESULTS: The standardized model for the community assessment, management and titration of clozapine is described. To date, 137 patients have been referred to this service and 100 patients (72%) attended for assessment. Of these, 33 have been initiated on clozapine while fifteen have had clozapine recommended but have not wished to undertake clozapine treatment. Other management options recommended have included augmentation strategies and long-acting injectable antipsychotics. CONCLUSION: The service had increased the number of patients receiving community assessment and initiation of clozapine by five-fold relative to the rate prior to the establishment of the service. The large number of referrals and high attendance rate indicates that there is clinical demand for the model. Systematic evaluation is required to determine the clinical and cost-effectiveness of this model and its potential application to other clinical settings.


Asunto(s)
Antipsicóticos/uso terapéutico , Clozapina/uso terapéutico , Servicios Comunitarios de Salud Mental/métodos , Trastornos Psicóticos/tratamiento farmacológico , Esquizofrenia/tratamiento farmacológico , Adulto , Manejo de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia del Tratamiento
20.
Prostaglandins Leukot Essent Fatty Acids ; 90(4): 105-115, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24374147

RESUMEN

The distribution of omega-6 and omega-3 polyunsaturated fatty acid (PUFA) intake in Western diets is disproportionate, containing an overabundance of the omega-6 PUFA, linoleic acid (LA; C18:2). Increased enrichment with LA has been shown to contribute to the enhancement of tumorigenesis in several cancer models. Previous work has indicated that phosphatidylinositol 3-kinase (PI3K) may play a key role in LA-induced tumorigenesis. However, the modes by which LA affects carcinogenesis have not been fully elucidated. In this study, a mechanism for LA-induced upregulation of cancer cell growth is defined. LA treatment enhanced cellular proliferation in BT-474 human breast ductal carcinoma and A549 human lung adenocarcinoma cell lines. Enrichment of LA increased cyclooxygenase (COX) activity and led to increases in prostaglandin E2 (PGE2), followed by increases in matrix metalloproteinase (MMP) and transforming growth factor alpha (TGF-α) levels, which are all key elements involved in the enhancement of cancer cell growth. Further investigation revealed that LA supplementation in both BT-474 breast and A549 lung cancer cell lines greatly increased the association between the scaffolding protein GRB2-associated-binding protein 1 (Gab1) and epidermal growth factor receptor (EGFR), although Gab1 protein levels were significantly decreased. These LA-induced changes were associated with increases in activated Akt (pAkt), a downstream signaling component in the PI3K pathway. Treatment with inhibitors of EGFR, PI3K and Gab1-specific siRNAs reversed the upregulation of pAkt, as well as the observed increases in cell proliferation by LA in both cell lines. A549 xenograft assessment in athymic nude mice fed high levels of LA exhibited similar increases in EGFR-Gab1 association and increased levels of pAkt, while mice fed with high levels of the omega-3 PUFA, docosahexaenoic acid (DHA; C22:6), demonstrated an opposite response. The involvement of Gab1 in LA-induced tumorigenesis was further defined utilizing murine cell lines that express high levels of Gab1. Significant increases in cell proliferation were observed with the addition of increasing concentrations of LA. However, no changes in cell proliferation were detected in the murine paired cell lines expressing little or no Gab1 protein, establishing Gab1 as major target in LA-induced enhancement of tumorigenesis.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/fisiología , Proliferación Celular , Ciclooxigenasa 2/fisiología , Ácido Linoleico/fisiología , Fosfatidilinositol 3-Quinasas/fisiología , Animales , Neoplasias de la Mama , Carcinogénesis/efectos de los fármacos , Carcinogénesis/metabolismo , Línea Celular Tumoral , Dinoprostona/sangre , Femenino , Humanos , Ácido Linoleico/farmacología , Neoplasias Pulmonares , Masculino , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Factor de Crecimiento Transformador alfa/sangre
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