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1.
ACS Biomater Sci Eng ; 6(10): 5941-5958, 2020 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-33320581

RESUMEN

Type 1 diabetes (T1D) pathophysiology, while incompletely understood, has in part been attributed to aberrant presentation of self-antigen plus proinflammatory costimulation by professional antigen-presenting cells (APCs). Therapies targeting dendritic cells (DCs) offer an avenue to restore antigen-specific tolerance by promoting presentation of self-antigen in an anti-inflammatory or suppressive context. Here, we describe a subcutaneously administered, dual-sized biodegradable microparticle (MP) platform that includes phagocytosable (∼1 µm) and nonphagocytosable (∼30 µm) MPs to deliver pro-tolerogenic factors both intra- and extracellularly, as well as the T1D-associated autoantigen, insulin, to DCs for amelioration of autoimmunity. This MP platform resulted in increased recruitment of DCs, suppressive skewing of DC phenotype with diminished expression of CD86 and MHC-II, increased regulatory T cell (Treg) frequency, and upregulated expression of the checkpoint inhibitor programmed cell death protein 1 (PD-1) on T cells. When administered concomitantly with anti-CD3 antibody, which provides transient T cell depletion while preserving Treg populations, in 12-week-old nonobese diabetic (NOD) mice, regulatory immune populations persisted out to 20 weeks of age; however, combination anti-CD3 and dual-sized MP (dMP) therapy failed to synergistically inhibit diabetes onset.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Animales , Células Dendríticas , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Inmunoterapia , Ratones , Ratones Endogámicos NOD
2.
Nat Rev Mater ; 4(6): 429-450, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32617176

RESUMEN

A cure for type 1 diabetes (T1D) would help millions of people worldwide, but remains elusive thus far. Tolerogenic vaccines and beta cell replacement therapy are complementary therapies that seek to address aberrant T1D autoimmune attack and subsequent beta cell loss. However, both approaches require some form of systematic immunosuppression, imparting risks to the patient. Biomaterials-based tools enable localized and targeted immunomodulation, and biomaterial properties can be designed and combined with immunomodulatory agents to locally instruct specific immune responses. In this Review, we discuss immunomodulatory biomaterial platforms for the development of T1D tolerogenic vaccines and beta cell replacement devices. We investigate nano- and microparticles for the delivery of tolerogenic agents and autoantigens, and as artificial antigen presenting cells, and highlight how bulk biomaterials can be used to provide immune tolerance. We examine biomaterials for drug delivery and as immunoisolation devices for cell therapy and islet transplantation, and explore synergies with other fields for the development of new T1D treatment strategies.

4.
Invest New Drugs ; 35(3): 324-333, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28150073

RESUMEN

Introduction This was an open-label, dose escalation (3 + 3 design), Phase I study of SOR-C13 in patients with advanced tumors of epithelial origin. Primary objectives were to assess safety/tolerability and pharmacokinetics. Secondary goals were to assess pharmacodynamics and efficacy of SOR-C13. Methods SOR-C13 was administered IV QD on days 1-3 and 8-10 of a 21-day cycle. Doses were 2.75 and 5.5 mg/kg (20-min infusion) and 1.375, 2.75, 4.13 and 6.2 mg/kg (90-min infusion). Toxicity was assessed by National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Dose limiting toxicity (DLT) was assessed within the first treatment cycle. Tumors were evaluated, using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, after two cycles. Results Twenty-three patients were treated. No drug-related serious adverse events occurred. DLTs occurred in six patients: asymptomatic, drug-related, transient Grade 2 hypocalcemia (4 patients), and unrelated Grade 3 anemia and Grade 3 atrial fibrillation, 1 patient each. Calcium and vitamin D supplementation eliminated further Grade 2 hypocalcemia. One Grade 3 treatment emergent adverse event, urticaria, was definitely related to SOR-C13. Four possibly drug-related, Grade 3 events (alanine aminotransferase and aspartate aminotransferase elevation, headache, and hypokalemia) were observed. Of 22 evaluable patients, 54.5% showed stable disease ranging from 2.8 to 12.5 months. The best response was a 27% reduction in a pancreatic tumor with a 55% reduction in CA19-9 levels at 6.2 mg/kg. Conclusion SOR-C13 was safe and tolerated up to 6.2 mg/kg. The Maximal Tolerated Dose (MTD) was not established. Stable disease suggested antitumor activity.


Asunto(s)
Antineoplásicos , Bloqueadores de los Canales de Calcio , Neoplasias/tratamiento farmacológico , Canales Catiónicos TRPV/antagonistas & inhibidores , Adulto , Anciano , Alanina Transaminasa/sangre , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Aspartato Aminotransferasas/sangre , Bloqueadores de los Canales de Calcio/efectos adversos , Bloqueadores de los Canales de Calcio/farmacocinética , Bloqueadores de los Canales de Calcio/farmacología , Bloqueadores de los Canales de Calcio/uso terapéutico , Canales de Calcio/genética , Femenino , Cefalea/inducido químicamente , Humanos , Hipocalcemia/inducido químicamente , Hipopotasemia/inducido químicamente , Queratina-18/sangre , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neoplasias/metabolismo , Péptidos/efectos adversos , Péptidos/farmacocinética , Péptidos/farmacología , Péptidos/uso terapéutico , ARN Mensajero/sangre , Canales Catiónicos TRPV/efectos adversos , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/farmacocinética , Canales Catiónicos TRPV/farmacología , Canales Catiónicos TRPV/uso terapéutico , Resultado del Tratamiento , Urticaria/inducido químicamente
5.
Eur J Clin Nutr ; 69(7): 850-5, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25351651

RESUMEN

BACKGROUND/OBJECTIVES: Objective and subjective measurement instruments have been used to estimate energy expenditure (EE) as alternatives to the doubly labeled water (DLW) methodology, but their relative validity for older adults remains uncertain. The purpose of this study was to validate an objective monitor (SenseWear Mini Armband) and a self-report instrument (7-Day Physical Activity Recall, 7D-PAR) relative to the DLW under free-living conditions in older adults. SUBJECTS/METHODS: Twenty-nine older adults (60-78 years) each wore the Mini for 14 consecutive days and completed two 7D-PARs after each week. For each measurement method, activity EE (AEE) was calculated as total EE (TEE)­measured resting metabolic rate (RMR)­diet induced thermogenesis (10% of TEE). TEE and AEE from the Mini and 7D-PAR were each compared with values from the DLW. RESULTS: Equivalence testing indicated that estimates of TEE from the Mini and the 7D-PAR were statistically equivalent to those measured with DLW; however, differences were evident for estimates of AEE. The Mini had smaller mean absolute percent error for TEE (8.0%) and AEE (28.4%) compared with the 7D-PAR (13.8 and 84.5%, respectively) and less systematic bias in the estimates. CONCLUSIONS: The Mini and 7D-PAR provided reasonably valid estimates of TEE but large errors in estimating AEE. The Mini and 7D-PAR have the potential to accurately estimate TEE for older adults.


Asunto(s)
Envejecimiento , Metabolismo Energético , Actividad Motora , Actigrafía , Anciano , Metabolismo Basal , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Autoinforme , Termogénesis
8.
Plant Dis ; 97(11): 1510, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30708473

RESUMEN

Colletotrichum chlorophyti was first reported in the United States in 2009 on soybean petioles (Glycine max [L.] Merr.) collected from Alabama, Illinois, and Mississippi (4). This species has not been reported to infect seed, unlike other Colletotrichum spp. (2). From the 2012 growing season, soybean seeds obtained from the National Agricultural Statistics Service representing 151 seed lots from growers' fields in 11 states were assayed by plating them on acidified potato dextrose agar (APDA). Before plating, seeds were surface disinfected by sequential immersion in 50% ethanol for 30 s, 20% commercial bleach for 1 min, two 1 min rinses in sterile distilled water, and kept at 25°C in the dark for 1 week. Infected seeds from one seed lot from Arkansas produced colonies similar to Colletotrichum spp. This seed lot was visually examined and divided into asymptomatic or discolored symptomatic seeds. Because of the limited number of seeds in the seed lot, 20 seeds that asymptomatic and 40 seeds that appeared symptomatic were assayed on APDA as previously described. Asymptomatic seeds did not produce any dark fungal colonies. Among the symptomatic seeds, five appeared to have flecked light gray seed coats with some larger grayish to black and irregular spots where cracks were sometimes formed, and they developed small black fungal masses or became entirely dark on the surface. Five fungal isolates were obtained from these infected seeds. On APDA, the isolates initially produced white to pink smooth-margined colonies, turned black with age, produced no aerial growth, and filled a 9 cm diameter petri dish within 10 days. DNA of one isolate was extracted for PCR and sequencing of the ITS region with ITS1 and ITS4 primers (3). From the BLAST analysis, the sequence was 100% identical to C. chlorophyti isolates, IMI 103806, and CBS 142.79 (Accession Nos. GU227894 and GU227895, respectively). To test for pathogenicity, the fungus was sub-cultured on APDA and eight APDA discs (4 mm diameter) were set into 50 ml potato dextrose broth inside a 250-ml flask and shook at a speed of 100 rpm at room temperature (24 ± 1°C) for 10 days. The mycelium was then weighed, fragmented with a blender, and resuspended in sterile distilled water to a final concentration of ~40 mg/ml. The mycelial suspension was sprayed on soybean seedlings of cv. Williams 82 (two plants/pot) at growth stage V1 to V2 until runoff. The inoculated plants were kept in a moist chamber (>90% relative humidity) for 48 h at 24 ± 1°C in the dark, and then transferred to normal plant growing conditions. At 5 days post-inoculation (dpi), the leaves showed typical symptoms caused by C. chlorophyti, including necrosis on the edge of young leaves and petioles, formation of irregular dark brown lesions, and leaves became scrolled (4). Setose acervuli, curved conidia with tapered ends (21.4 ± 1.1 × 3.8 ± 0.3 µm), and chlamydospores were found on the detached symptomatic leaves after 12 dpi. No perithecia formed. The morphology matched the description of C. chlorophyti (1,4). To our knowledge, this is the first report of C. chlorophyti in Arkansas and the first time that this species has been reported infecting seed of any plant. References: (1) S. Chandra and R. N. Tandon. Curr. Sci. 34:565, 1965. (2) G. L. Hartman et al. Page 13 in: Compendium of Soybean Diseases, APS Press, St. Paul, MN, 1999. (3) T. J. White et al. Page 315 in: PCR Protocols. A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990. (4) H.-C. Yang et al. Plant Dis. 96:1699, 2012.

9.
Pediatr Pulmonol ; 48(8): 772-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22997178

RESUMEN

Severe lower respiratory infection (LRI) is believed to be one precursor of protracted bacterial bronchitis, chronic moist cough (CMC), and chronic suppurative lung disease. The aim of this study was to determine and to describe the presence of respiratory morbidity in young children 1 year after being hospitalized with a severe LRI. Children aged less than 2 years admitted from August 1, 2007 to December 23, 2007 already enrolled in a prospective epidemiology study (n = 394) were included in this second study only if they had a diagnosis of severe bronchiolitis or of pneumonia with no co-morbidities (n = 237). Funding allowed 164 to be identified chronologically, 131 were able to be contacted, and 94 agreed to be assessed by a paediatrician 1 year post index admission. Demographic information, medical history and a respiratory questionnaire was recorded, examination, pulse oximetry, and chest X-ray (CXR) were performed. The predetermined primary endpoints were; (i) history of CMC for at least 3 months, (ii) the presence of moist cough and/or crackles on examination in clinic, and (iii) an abnormal CXR when seen at a time of stability. Each CXR was read by two pediatric radiologists blind to the individuals' current health. Results showed 30% had a history of CMC, 32% had a moist cough and/or crackles on examination in clinic, and in 62% of those with a CXR it was abnormal. Of the 81 children with a readable follow-up X-ray, 11% had all three abnormal outcomes, and 74% had one or more abnormal outcomes. Three children had developed bronchiectasis on HRCT. The majority of children with a hospital admission at <2 years of age for severe bronchiolitis or pneumonia continued to have respiratory morbidity 1 year later when seen at a time of stability, with a small number already having sustained significant lung disease.


Asunto(s)
Estado de Salud , Hospitalización , Infecciones del Sistema Respiratorio/epidemiología , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Morbilidad/tendencias , Nueva Zelanda/epidemiología , Pronóstico , Radiografía Torácica , Infecciones del Sistema Respiratorio/diagnóstico por imagen , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo
10.
Br J Ophthalmol ; 93(12): 1606-11, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19635720

RESUMEN

AIMS: To describe previously unreported retinal findings in patients with Alport Syndrome (AS), as well as review the range of ophthalmic manifestations. METHODS: Retrospective review of clinical records of patients with AS. RESULTS: Nine patients with AS were identified, of whom three had no eye findings, four showed classic features of AS, and two had new findings, bull's eye and vitelliform maculopathy. The genetic mutation responsible for the disease in the patient with vitelliform subretinal deposits was identified. CONCLUSIONS: Patients with AS can present with a variety of ophthalmic manifestations. Bull's eye maculopathy and vitelliform deposits can be features of AS. The mechanism of these new macular findings remains unknown. Possible pathophysiological overlap with other maculopathies including age-related macular degeneration is discussed.


Asunto(s)
Enfermedades Hereditarias del Ojo/diagnóstico , Nefritis Hereditaria/diagnóstico , Enfermedades de la Retina/diagnóstico , Adulto , Femenino , Fluorescencia , Humanos , Hiperpigmentación/diagnóstico , Hiperpigmentación/genética , Masculino , Enfermedades de la Retina/genética , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Adulto Joven
11.
Arch Dis Child ; 94(10): 745-51, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18838420

RESUMEN

BACKGROUND: A tailor-made serogroup B outer membrane vesicle vaccine was evaluated in the context of a serogroup B meningococcal epidemic dominated by Neisseria meningitidis strain B:4:P1.7b,4. OBJECTIVE: To determine the safety, reactogenicity and immunogenicity in infants aged 6-8 months of a meningococcal B vaccine developed against the New Zealand epidemic strain. DESIGN, SETTING AND PARTICIPANTS: Observer-blind, randomised, controlled trial conducted in 296 healthy infants in Auckland, New Zealand. INTERVENTION: Infants were randomised 4:1 to receive three doses of New Zealand candidate vaccine (epidemic strain NZ98/254, B:4:P1.7b,4) or meningococcal C conjugate vaccine at 6-weekly intervals. MAIN OUTCOME MEASURES: Immune response was determined by human complement mediated serum bactericidal assay. Sero-response was a fourfold or greater rise in titre compared to baseline, with baseline titres <4 required to increase to >or=8. Blood samples were taken before vaccination, 6 weeks after dose two, and 4 weeks after dose three. Local and systemic reactions were recorded for 7 days following vaccination. RESULTS: Sero-response to the candidate vaccine strain, NZ98/254, was demonstrated in 74% of vaccinees (95% CI: 68% to 80% intention-to-treat; 67% to 79% per protocol) after three doses of New Zealand candidate vaccine. No meningococcal C conjugate vaccine recipients were sero-responders to NZ98/254 after three doses. Both vaccines were well tolerated with no vaccine related serious adverse events. CONCLUSIONS: Our data indicate that the New Zealand candidate vaccine administered in three doses to this group of 6-8-month-old infants was safe and immunogenic against the candidate vaccine strain NZ98/254 (Neisseria meningitidis B:4:P1.7b,4).


Asunto(s)
Anticuerpos Antibacterianos/biosíntesis , Meningitis Meningocócica/prevención & control , Vacunas Meningococicas/inmunología , Neisseria meningitidis Serogrupo B/inmunología , Anticuerpos Antibacterianos/sangre , Femenino , Humanos , Esquemas de Inmunización , Lactante , Masculino , Meningitis Meningocócica/inmunología , Vacunas Meningococicas/efectos adversos , Método Simple Ciego
13.
Arch Dis Child ; 93(6): 474-8, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18337284

RESUMEN

BACKGROUND: Rheumatic fever is a preventable chronic disease preceded by group A beta-haemolytic streptococcal (GABHS) pharyngitis. OBJECTIVE: To test the non-inferiority of once-daily (QD) oral amoxicillin to the recommended twice-daily (BID) oral penicillin V in GABHS pharyngitis. METHODS: This was a randomised non-inferiority trial carried out in a school-based clinic in New Zealand. Children presenting with GABHS pharyngitis were randomised to oral amoxicillin 1500 mg QD (or 750 mg if bodyweight was

Asunto(s)
Amoxicilina/administración & dosificación , Antibacterianos/administración & dosificación , Penicilina V/administración & dosificación , Faringitis/tratamiento farmacológico , Fiebre Reumática/prevención & control , Infecciones Estreptocócicas/tratamiento farmacológico , Enfermedad Aguda , Niño , Preescolar , Esquema de Medicación , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Nueva Zelanda , Faringitis/microbiología , Fiebre Reumática/tratamiento farmacológico , Infecciones Estreptocócicas/microbiología , Resultado del Tratamiento
15.
Br J Pharmacol ; 150(3): 369-79, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17179948

RESUMEN

BACKGROUND AND PURPOSE: A bradykinin (BK) B2 receptor (B2R) antagonist, B-9870 (CU201), has been proposed to behave as a 'biased agonist' at B2Rs and to exert anti-neoplasic effects. It was unclear whether these effects were determined by the activation of B2Rs by the drug. B-9870 was evaluated for antagonism or stimulation of several responses mediated by the rabbit B2R or B1 receptor (B1R); its anti-proliferative activity was also characterized. EXPERIMENTAL APPROACH AND KEY RESULTS: B-9870 was an insurmountable B2R antagonist in the rabbit jugular vein contractility assay, but a partial agonist in HEK 293 cells expressing the rabbit B2R or a green fluorescent protein (GFP) conjugate of the latter (ERK1/2 phosphorylation, [Ca2+]i, [3H]-arachidonate release, endocytosis). The agonist-like effects of B-9870 were inhibited by the B2R antagonist LF 16.0687 and absent in untransfected cells. In addition, B-9870 was a surmontable antagonist of the rabbit B1R in the aorta contractility assay, and blocked Lys-des-Arg9-BK-induced ERK1/2 phosphorylation in HEK 293 cells expressing a fluorescent B1R conjugate. B-9870 inhibited the growth of MDA-MB-231 cells. The latter effect was not influenced by B1R or B2R antagonists and was not apoptotic. MDA-MB-231 cells expressed a small population of B2Rs but no B1Rs; they responded to BK (small calcium transients) and B-9870 behaved as an antagonist. CONCLUSION AND IMPLICATIONS: B-9870 is a dual B1R and B2R antagonist with confirmed stimulating effects at the B2R in high expression systems only. Its cell type-specific anti-proliferative effect occurs at a high concentration, independently from kinin receptors and apoptosis.


Asunto(s)
Antineoplásicos/farmacología , Oligopéptidos/farmacología , Receptor de Bradiquinina B1/efectos de los fármacos , Receptor de Bradiquinina B2/efectos de los fármacos , Animales , Línea Celular , Conejos , Receptor de Bradiquinina B1/metabolismo , Receptor de Bradiquinina B2/metabolismo
17.
Eye (Lond) ; 21(2): 257; author reply 257-8, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16778817
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