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1.
PLoS Pathog ; 18(3): e1010337, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35255101

RESUMEN

HLA-A*11:01 is one of the most prevalent human leukocyte antigens (HLAs), especially in East Asian and Oceanian populations. It is also highly expressed in Indigenous people who are at high risk of severe influenza disease. As CD8+ T cells can provide broadly cross-reactive immunity to distinct influenza strains and subtypes, including influenza A, B and C viruses, understanding CD8+ T cell immunity to influenza viruses across prominent HLA types is needed to rationally design a universal influenza vaccine and generate protective immunity especially for high-risk populations. As only a handful of HLA-A*11:01-restricted CD8+ T cell epitopes have been described for influenza A viruses (IAVs) and epitopes for influenza B viruses (IBVs) were still unknown, we embarked on an epitope discovery study to define a CD8+ T cell landscape for HLA-A*11:01-expressing Indigenous and non-Indigenous Australian people. Using mass-spectrometry, we identified IAV- and IBV-derived peptides presented by HLA-A*11:01 during infection. 79 IAV and 57 IBV peptides were subsequently screened for immunogenicity in vitro with peripheral blood mononuclear cells from HLA-A*11:01-expressing Indigenous and non-Indigenous Australian donors. CD8+ T cell immunogenicity screening revealed two immunogenic IAV epitopes (A11/PB2320-331 and A11/PB2323-331) and the first HLA-A*11:01-restricted IBV epitopes (A11/M41-49, A11/NS1186-195 and A11/NP511-520). The immunogenic IAV- and IBV-derived peptides were >90% conserved among their respective influenza viruses. Identification of novel immunogenic HLA-A*11:01-restricted CD8+ T cell epitopes has implications for understanding how CD8+ T cell immunity is generated towards IAVs and IBVs. These findings can inform the development of rationally designed, broadly cross-reactive influenza vaccines to ensure protection from severe influenza disease in HLA-A*11:01-expressing individuals.


Asunto(s)
Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Australia , Linfocitos T CD8-positivos , Epítopos de Linfocito T , Antígenos HLA-A , Humanos , Pueblos Indígenas , Virus de la Influenza B , Leucocitos Mononucleares , Péptidos
2.
Clin Imaging ; 46: 44-52, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28723585

RESUMEN

OBJECTIVE: Supplement tomosynthesis-detected architectural distortions (AD) with CESM to better characterize malignant vs benign lesions. METHODS: Retrospective review CESM prior to biopsied AD. Pathology: benign, radial scar, or malignant. RESULTS: 49 lesions (45 patients). 29 invasive cancers, 1 DCIS (range, 0.4-4.7cm); 9 radial scars; 10 benign. 37 (75.5%) ADs had associated enhancement. PPV 78.4% (29/37), sensitivity 96.7% (29/30); specificity, 57.9% (11/19); NPV, 91.7% (11/12). False-positive rate 21.6% (8/37); false-negative rate, 8.3% (1/12). Accuracy 81.6% (40/49). CONCLUSIONS: High sensitivity and NPV of CESM in patients with AD is promising as an adjunct tool in diagnosing malignancy and avoiding unnecessary biopsy, respectively.


Asunto(s)
Neoplasias de la Mama/patología , Medios de Contraste , Mamografía/métodos , Adulto , Anciano , Biopsia , Neoplasias de la Mama/diagnóstico por imagen , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad
3.
BMC Endocr Disord ; 17(1): 26, 2017 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-28525998

RESUMEN

BACKGROUND: Androsterone glucuronide (ADTG) concentrations have been suggested as a marker of the effects of androgens at the target tissue level. As the mechanism for hyperandrogenemia in obese and nonobese polycystic ovary syndrome (PCOS) may differ, this study compared the different androgen parameters in non-obese compared to obese women with PCOS, and in normal subjects. METHODS: Eleven non-obese and 14 obese women with PCOS were recruited and compared to 11 control women without PCOS. Total testosterone, dehydroepiandrosterone sulphate (DHEAS), ADTG, and androstenedione were analysed using gold standard tandem mass spectrometry, and the free androgen index (FAI) was calculated. RESULTS: Total testosterone, ADTG and androstendione levels did not differ between non-obese (body mass index (BMI) ≤25 kg/m2) and obese PCOS (BMI >25 kg/m2) but all were significantly higher than for controls (p < 0.01). The ADTG to DHEAS ratio was significantly elevated 39 ± 6 (p < 0.01) in obese PCOS in comparison to non-obese PCOS and controls (28 ± 5 and 29 ± 4, respectively). The free androgen index (FAI) and insulin resistance (HOMA-IR) were significantly higher in obese PCOS compared to non-obese PCOS and controls (p < 0.01). DHEAS was significantly higher in the non-obese versus obese PCOS (p < 0.01). All androgen parameters were significantly lower and sex hormone binding globulin (SHBG) significantly higher in normal subjects compared to those with obese and non-obese PCOS. CONCLUSIONS: The ADTG:DHEAS ratio was significantly elevated in obese PCOS compared to non-obese PCOS and controls suggesting that this may be a novel biomarker discriminatory for obese PCOS subjects, perhaps being driven by higher hepatic 5α reductase activity increasing ADTG formation in these women.


Asunto(s)
Androsterona/análogos & derivados , Sulfato de Deshidroepiandrosterona/sangre , Obesidad/sangre , Síndrome del Ovario Poliquístico/sangre , Población Blanca , Adolescente , Adulto , Androsterona/sangre , Biomarcadores/sangre , Femenino , Humanos , Obesidad/diagnóstico , Obesidad/epidemiología , Síndrome del Ovario Poliquístico/diagnóstico , Síndrome del Ovario Poliquístico/epidemiología , Adulto Joven
4.
Proc Natl Acad Sci U S A ; 113(16): 4440-5, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27036003

RESUMEN

Memory CD8(+)T lymphocytes (CTLs) specific for antigenic peptides derived from internal viral proteins confer broad protection against distinct strains of influenza A virus (IAV). However, immune efficacy can be undermined by the emergence of escape mutants. To determine how T-cell receptor (TCR) composition relates to IAV epitope variability, we used ex vivo peptide-HLA tetramer enrichment and single-cell multiplex analysis to compare TCRs targeted to the largely conserved HLA-A*0201-M158and the hypervariable HLA-B*3501-NP418antigens. The TCRαßs for HLA-B*3501-NP418 (+)CTLs varied among individuals and across IAV strains, indicating that a range of mutated peptides will prime different NP418-specific CTL sets. Conversely, a dominant public TRAV27/TRBV19(+)TCRαß was selected in HLA-A*0201(+)donors responding to M158 This public TCR cross-recognized naturally occurring M158variants complexed with HLA-A*0201. Ternary structures showed that induced-fit molecular mimicry underpins TRAV27/TRBV19(+)TCR specificity for the WT and mutant M158peptides, suggesting the possibility of universal CTL immunity in HLA-A*0201(+)individuals. Combined with the high population frequency of HLA-A*0201, these data potentially explain the relative conservation of M158 Moreover, our results suggest that vaccination strategies aimed at generating broad protection should incorporate variant peptides to elicit cross-reactive responses against other specificities, especially those that may be relatively infrequent among IAV-primed memory CTLs.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Antígeno HLA-A2 , Inmunidad Celular , Virus de la Influenza A/inmunología , Gripe Humana , Receptores de Antígenos de Linfocitos T alfa-beta , Animales , Antígenos Virales/inmunología , Perros , Femenino , Antígeno HLA-A2/genética , Antígeno HLA-A2/inmunología , Humanos , Memoria Inmunológica/genética , Virus de la Influenza A/genética , Gripe Humana/genética , Gripe Humana/inmunología , Células de Riñón Canino Madin Darby , Masculino , Péptidos/genética , Péptidos/inmunología , Péptidos/farmacología , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Vacunación , Proteínas Virales/genética , Proteínas Virales/inmunología , Proteínas Virales/farmacología
5.
Sci Transl Med ; 8(331): 331ra41, 2016 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-27009270

RESUMEN

Sporadic inclusion body myositis (sIBM) is the commonest severe myopathy in patients more than 50 years of age. Previous therapeutic trials have targeted the inflammatory features of sIBM but all have failed. Because protein dyshomeostasis may also play a role in sIBM, we tested the effects of targeting this feature of the disease. Using rat myoblast cultures, we found that up-regulation of the heat shock response with arimoclomol reduced key pathological markers of sIBM in vitro. Furthermore, in mutant valosin-containing protein (VCP) mice, which develop an inclusion body myopathy, treatment with arimoclomol ameliorated disease pathology and improved muscle function. We therefore evaluated arimoclomol in an investigator-led, randomized, double-blind, placebo-controlled, proof-of-concept trial in sIBM patients and showed that arimoclomol was safe and well tolerated. Although arimoclomol improved some IBM-like pathology in the mutant VCP mouse, we did not see statistically significant evidence of efficacy in the proof-of-concept patient trial.


Asunto(s)
Homeostasis , Miositis por Cuerpos de Inclusión/metabolismo , Proteínas/metabolismo , Adenosina Trifosfatasas/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Proteínas de Ciclo Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Ensayos Clínicos como Asunto , Estrés del Retículo Endoplásmico/efectos de los fármacos , Proteínas HSP70 de Choque Térmico/metabolismo , Humanos , Hidroxilaminas/farmacología , Hidroxilaminas/uso terapéutico , Mediadores de Inflamación/metabolismo , Ratones , Contracción Muscular/efectos de los fármacos , Fuerza Muscular/efectos de los fármacos , Mutación/genética , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Mioblastos/patología , Miositis por Cuerpos de Inclusión/patología , Miositis por Cuerpos de Inclusión/fisiopatología , Ratas , Resultado del Tratamiento , Proteína que Contiene Valosina
6.
Immunol Cell Biol ; 94(4): 367-77, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26493179

RESUMEN

Indigenous populations, including Indigenous Australians, are highly susceptible to severe influenza disease and the underlying mechanisms are unknown. We studied immune and genetic factors that could predicate severe influenza disease in Indigenous Australians enrolled in the LIFT study: looking into influenza T-cell immunity. To examine CD8(+) T-cell immunity, we characterised human leukocyte antigen (HLA) profiles. HLA typing confirmed previous studies showing predominant usage of HLA-A*02:01, 11:01, 24:02, 34:01 and HLA-B*13:01, 15:21, 40:01/02, 56:01/02 in Indigenous Australians. We identified two new HLA alleles (HLA-A*02:new and HLA-B*56:new). Modelling suggests that variations within HLA-A*02:new (but not HLA-B56:new) could affect peptide binding. There is a relative lack of known influenza epitopes for the majority of these HLAs, with the exception of a universal HLA-A*02:01-M158 epitope and proposed epitopes presented by HLA-A*11:01/HLA-A*24:02. To dissect universal CD8(+) T-cell responses, we analysed the magnitude, function and T-cell receptor (TCR) clonality of HLA-A*02:01-M158(+)CD8(+) T cells. We found comparable IFN-γ, TNF and CD107a and TCRαß characteristics in Indigenous and non-Indigenous Australians, suggesting that the ~15% of Indigenous people that express HLA-A*02:01 have universal influenza-specific CD8(+) T-cell immunity. Furthermore, the frequency of an influenza host risk factor, IFITM3-C/C, was comparable between Indigenous Australians and Europeans, suggesting that expression of this allele does not explain increased disease severity at a population level. Our study indicates a need to identify novel influenza-specific CD8(+) T-cell epitopes restricted by HLA-A and HLA-B alleles prevalent in Indigenous populations for the rational design of universal T-cell vaccines.


Asunto(s)
Linfocitos T CD8-positivos/fisiología , Antígenos HLA/genética , Gripe Humana/inmunología , Nativos de Hawái y Otras Islas del Pacífico , Adulto , Alelos , Células Cultivadas , Epítopos de Linfocito T/metabolismo , Femenino , Prueba de Histocompatibilidad , Humanos , Vacunas contra la Influenza , Gripe Humana/genética , Interferón gamma/metabolismo , Proteína 1 de la Membrana Asociada a los Lisosomas/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , Proteínas de Unión al ARN/metabolismo , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Riesgo , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas de la Matriz Viral/metabolismo
7.
Proc Natl Acad Sci U S A ; 111(3): 1049-54, 2014 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-24395804

RESUMEN

The absence of preexisting neutralizing antibodies specific for the novel A (H7N9) influenza virus indicates a lack of prior human exposure. As influenza A virus-specific CD8(+) T lymphocytes (CTLs) can be broadly cross-reactive, we tested whether immunogenic peptides derived from H7N9 might be recognized by memory CTLs established following infection with other influenza strains. Probing across multiple ethnicities, we identified 32 conserved epitopes derived from the nucleoprotein (NP) and matrix-1 (M1) proteins. These NP and M1 peptides are presented by HLAs prevalent in 16-57% of individuals. Remarkably, some HLA alleles (A*0201, A*0301, B*5701, B*1801, and B*0801) elicit robust CTL responses against any human influenza A virus, including H7N9, whereas ethnicities where HLA-A*0101, A*6801, B*1501, and A*2402 are prominent, show limited CTL response profiles. By this criterion, some groups, especially the Alaskan and Australian Indigenous peoples, would be particularly vulnerable to H7N9 infection. This dissection of CTL-mediated immunity to H7N9 thus suggests strategies for both vaccine delivery and development.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Subtipo H7N9 del Virus de la Influenza A/inmunología , Gripe Humana/etnología , Gripe Humana/inmunología , Australia , Reacciones Cruzadas/inmunología , Cristalografía por Rayos X , Epítopos de Linfocito T/inmunología , Etnicidad , Antígenos HLA/inmunología , Antígenos HLA-A/inmunología , Humanos , Memoria Inmunológica , Vacunas contra la Influenza/inmunología , Leucocitos Mononucleares/citología , Funciones de Verosimilitud , Mutación , Péptidos/inmunología
8.
J Chromatogr B Analyt Technol Biomed Life Sci ; 878(7-8): 695-9, 2010 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-20117968

RESUMEN

In patients with carcinoid disease, urinary concentration of the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA) is currently used to monitor disease progression or response to treatment as it is the metabolic end-product resulting from free and stored serotonin turnover. However, due to the undignified, cumbersome and error-prone nature of 24-h urine collections, there is constant pressure to replace them. It has been demonstrated using high performance liquid chromatography (HPLC) with fluorescence detection technology that plasma can achieve this, with the added advantage that it can be used for diagnostic purposes also. Here we describe a much simpler method using liquid chromatography-tandem mass spectrometry (LC-MS/MS) that is twice as fast as a HPLC method currently in routine use. The sample preparation protocol requires 50 micorL of plasma and a simple protein precipitation step facilitated by acetonitrile. Chromatography was performed on a Phenomenex C18 Security Guard column coupled to a SIELC Primesep B reversed-phase, anion-exchange dual chemistry column and methanolic mobile phase gradient elution. Eluant was directly connected to a Waters Quattro Premier XE tandem mass spectrometer operating in positive ion mode. We detected multiple reaction monitoring transitions m/z 191.9>145.6 and 193.9>147.6 for 5-HIAA and d2-5-HIAA respectively, which co-eluted at 2.1 min. Ion suppression was negligible, recovery from spiked plasma was 103% (range 97-113%) and the method showed good linearity to 10,000 nmol/L (r(2)=0.999). Within-batch and between-batch imprecision was <10% and bias <15% at 3 concentrations, the limit of detection was 5 nmol/L and lower limit of quantitation 15 nmol/L. No interference was observed with l-tryptophan or 5-hydroxytryptamine. Comparison of LC-MS/MS and HPLC showed good agreement between the two methods but this LC-MS/MS assay displays several advantages; it requires 10-fold less sample, has a simpler extraction procedure and extended linearity, thus increasing laboratory throughput, lowering reagent costs and removing the need to dilute samples in patients with established carcinoid disease being monitored for therapeutic efficacy.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida/métodos , Ácido Hidroxiindolacético/sangre , Espectrometría de Masas en Tándem/métodos , Tumor Carcinoide/sangre , Humanos , Modelos Lineales , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
Acta Reumatol Port ; 34(2A): 161-82, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19474772

RESUMEN

Sporadic inclusion body myositis (sIBM) is considered to be the most common acquired muscle disease associated with aging. It is a disabling disorder still without effective treatment. sIBM causes weakness and atrophy of the distal and proximal muscles. Involvement of quadriceps and deep finger flexors are clues to early diagnosis. Dysphagia in the course of the disease is common. Muscle biopsy shows chronic myopathic features, lymphocytic infiltration invading non-necrotic fibbers, rimmed vacuoles and accumulation of amyloid-related proteins. It remains uncertain whether sIBM is primarily an immune-mediated inflammatory myopathy or a degenerative myopathy with an associated inflammatory component. This review describes the epidemiology and clinical features of the disease as well as the current genetic and pathogenic concepts and therapeutic approaches. Despite recent clues, in many respects sIBM remains an unsolved mystery.


Asunto(s)
Miositis por Cuerpos de Inclusión , Humanos , Miositis por Cuerpos de Inclusión/diagnóstico , Miositis por Cuerpos de Inclusión/epidemiología , Miositis por Cuerpos de Inclusión/etiología , Miositis por Cuerpos de Inclusión/terapia
10.
Clin Nurse Spec ; 23(3): 131-7, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19395889

RESUMEN

OBJECTIVE: The purpose of this study was to assess the incidence of pain in inpatient and outpatient populations experiencing invasive procedures. BACKGROUND: Nursing staff consulted the clinical nurse specialist regarding a patient they assessed who was not medicated appropriately and experienced significant procedural pain. As a result, a Procedural Pain Task Force was created to research the incidence of procedural pain and create evidence-based practice protocols. METHODS: A convenience sample of 358 patients undergoing diagnostic or therapeutic invasive procedures (surgery excluded) was studied. Variables for analysis included demographic data, procedure type, medication, and perceived pain before, during, and after the procedures. RESULTS: Patients who were not premedicated had lower mean pain scores (mean, 1.81) than patients who did receive medication before a potentially painful procedure (mean, 3.64). Age was negatively correlated with perceived pain; thus, the greater the patient age, the lower the pain score. Sex, premedication, and type of procedure were positively correlated with perceived pain scores. Sixty-three subjects reporting pain scores of 5 or greater during a procedure were further evaluated. CONCLUSIONS: Results were used to develop procedural pain guidelines and a physician order set as well as a medication reference grid to assist clinicians in the management of procedural pain. Furthermore, nurses were empowered by the revised guidelines to advocate for relief of pain based on the nursing assessment.


Asunto(s)
Enfermeras Clínicas/organización & administración , Rol de la Enfermera , Dolor/prevención & control , Derivación y Consulta/organización & administración , Adulto , Anciano , Anciano de 80 o más Años , Analgesia/métodos , Analgesia/estadística & datos numéricos , Técnicas y Procedimientos Diagnósticos/efectos adversos , Práctica Clínica Basada en la Evidencia/organización & administración , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Evaluación en Enfermería , Evaluación de Resultado en la Atención de Salud , Dolor/diagnóstico , Dolor/epidemiología , Dolor/etiología , Dimensión del Dolor , Grupo de Atención al Paciente/organización & administración , Guías de Práctica Clínica como Asunto , Premedicación/métodos , Premedicación/estadística & datos numéricos , Autonomía Profesional , Comité de Profesionales/organización & administración , Índice de Severidad de la Enfermedad , Terapéutica/efectos adversos
11.
J Foot Ankle Surg ; 47(5): 430-3, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18725123

RESUMEN

UNLABELLED: Diabetic foot ulcers can be difficult to treat for a variety of reasons, and may result in amputation. The use of skin grafts can often be a useful method of achieving wound coverage and subsequent healing of diabetic foot ulcers; however, this method of treatment requires creation of a donor site wound that adds to the patient's overall wound burden. Application of an acellular regenerative tissue matrix may eliminate the need for harvesting a skin graft in order to cover a nonhealing wound. The use of vacuum-assisted wound closure has been shown to promote an environment that enhances wound bed contraction and surface epithelialization. The combination of an acellular regenerative tissue matrix with vacuum-assisted wound closure can be used to promote healing in the management of a nonhealing diabetic foot wound. LEVEL OF CLINICAL EVIDENCE: x.


Asunto(s)
Pie Diabético/terapia , Terapia de Presión Negativa para Heridas , Trasplante de Piel , Desbridamiento , Humanos , Masculino , Persona de Mediana Edad , Ingeniería de Tejidos , Trasplante Homólogo , Cicatrización de Heridas
12.
J Clin Endocrinol Metab ; 90(1): 379-85, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15507507

RESUMEN

IGFs are critical in fetal growth because of their role in placental development and function. In this study, we used adenovirus (Ad-IGF) to deliver sense or antisense IGF-I or IGF-II cDNA to human primary placental fibroblasts (PPF) in vitro to determine whether this could lead to enhanced placental cell function. PPFs virally transfected with Ad-IGF-I or Ad-IGF-II showed 7-fold (P < 0.01) and 3-fold (P < 0.01) increases in [(3)H]thymidine incorporation at 48 h post infection compared with nontransfected controls. In a coculture system designed to assess cell migration, nontransfected PPF cells positioned over a monolayer transfected by Ad-IGF-I or Ad-IGF-II showed a more than 10-fold (P < 0.01) and a 7-fold (P < 0.01) increase in migration compared with cells positioned above a nontransfected monolayer. After 96 h in culture, PPFs transfected with sense Ad-IGF-I or Ad-IGF-II showed 2% apoptosis compared with 16% of nontransfected cells, whereas 37% and 25% of cells transfected with antisense Ad-IGF-I or Ad-IGF-II were apoptotic. This work has established that cells of placental origin are amenable to adenoviral transfection and that IGFs exert autocrine and paracrine effects on proliferation, migration, and survival, suggesting that enhancement of IGF levels in the placenta may augment placental function and increase fetal growth.


Asunto(s)
Terapia Genética , Factor II del Crecimiento Similar a la Insulina/fisiología , Factor I del Crecimiento Similar a la Insulina/fisiología , Placenta/citología , Placenta/fisiología , Adenoviridae/genética , Apoptosis , División Celular , Movimiento Celular , Células Cultivadas , Femenino , Desarrollo Fetal , Fibroblastos/fisiología , Humanos , Factor I del Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/genética , Embarazo , Primer Trimestre del Embarazo , Transfección
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