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1.
Regul Toxicol Pharmacol ; 134: 105219, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35835397

RESUMEN

Our aim is to develop and apply next generation approaches to skin allergy risk assessment that do not require new animal test data and better quantify uncertainties. Quantitative risk assessment for skin sensitisation uses safety assessment factors to extrapolate from the point of departure to an acceptable human exposure level. It is currently unclear whether these safety assessment factors are appropriate when using non-animal test data to derive a point-of departure. Our skin allergy risk assessment model Defined Approach uses Bayesian statistics to infer a human-relevant metric of sensitiser potency with explicit quantification of uncertainty, using any combination of human repeat insult patch test, local lymph node assay, direct peptide reactivity assay, KeratinoSens™, h-CLAT or U-SENS™ data. Here we describe the incorporation of benchmark exposures pertaining to use of consumer products with clinical data supporting a high/low risk categorisation for skin sensitisation. Margins-of-exposure (potency estimate to consumer exposure level ratio) are regressed against the benchmark risk classifications, enabling derivation of a risk metric defined as the probability that an exposure is low risk. This approach circumvents the use of safety assessment factors and provides a simple and transparent mechanism whereby clinical experience can directly feed-back into risk assessment decisions.


Asunto(s)
Dermatitis Alérgica por Contacto , Alternativas a las Pruebas en Animales , Animales , Teorema de Bayes , Benchmarking , Toma de Decisiones , Dermatitis Alérgica por Contacto/etiología , Humanos , Medición de Riesgo , Piel
2.
Regul Toxicol Pharmacol ; 131: 105159, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35311660

RESUMEN

Our aim is to develop and apply next generation approaches to skin allergy risk assessment (SARA) that do not require new animal test data and better quantify uncertainties. Significant progress has been made in the development of New Approach Methodologies (NAMs), non-animal test methods, for assessment of skin sensitisation and there is now focus on their application to derive potency information for use in Next Generation Risk Assessment (NGRA). The SARA model utilises a Bayesian statistical approach to infer a human-relevant metric of sensitiser potency and a measure of risk associated with a given consumer exposure based upon any combination of human repeat insult patch test, local lymph node, direct peptide reactivity assay, KeratinoSens™, h-CLAT or U-SENS™ data. Here we have applied the SARA model within our weight of evidence NGRA framework for skin allergy to three case study materials in four consumer products. Highlighting how to structure the risk assessment, apply NAMs to derive a point of departure and conclude on consumer safety risk. NGRA based upon NAMs were, for these exposures, at least as protective as the historical risk assessment approaches. Through such case studies we are building our confidence in using NAMs for skin allergy risk assessment.


Asunto(s)
Cosméticos , Dermatitis Alérgica por Contacto , Hipersensibilidad , Alternativas a las Pruebas en Animales/métodos , Animales , Teorema de Bayes , Toma de Decisiones , Dermatitis Alérgica por Contacto/diagnóstico , Dermatitis Alérgica por Contacto/etiología , Medición de Riesgo/métodos , Piel
3.
Emerg Infect Dis ; 27(3): 687-693, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33400642

RESUMEN

Since the first wave of coronavirus disease in March 2020, citizens and permanent residents returning to New Zealand have been required to undergo managed isolation and quarantine (MIQ) for 14 days and mandatory testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As of October 20, 2020, of 62,698 arrivals, testing of persons in MIQ had identified 215 cases of SARS-CoV-2 infection. Among 86 passengers on a flight from Dubai, United Arab Emirates, that arrived in New Zealand on September 29, test results were positive for 7 persons in MIQ. These passengers originated from 5 different countries before a layover in Dubai; 5 had negative predeparture SARS-CoV-2 test results. To assess possible points of infection, we analyzed information about their journeys, disease progression, and virus genomic data. All 7 SARS-CoV-2 genomes were genetically identical, except for a single mutation in 1 sample. Despite predeparture testing, multiple instances of in-flight SARS-CoV-2 transmission are likely.


Asunto(s)
Aeronaves , COVID-19 , Cuarentena , SARS-CoV-2/aislamiento & purificación , COVID-19/diagnóstico , COVID-19/transmisión , Humanos , Máscaras , Nueva Zelanda , Distanciamiento Físico , SARS-CoV-2/clasificación , Emiratos Árabes Unidos
4.
J Virol ; 94(7)2020 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-31941786

RESUMEN

Despite evidence that antibodies targeting the influenza virus neuraminidase (NA) protein can be protective and are broadly cross-reactive, the immune response to NA during infection is poorly understood compared to the response to hemagglutinin (HA) protein. As such, we compared the antibody profile to HA and NA in two naturally infected human cohorts in Auckland, New Zealand: (i) a serosurvey cohort, consisting of pre- and post-influenza season sera from PCR-confirmed influenza cases (n = 50), and (ii) an immunology cohort, consisting of paired sera collected after PCR-confirmation of infection (n = 94). The induction of both HA and NA antibodies in these cohorts was influenced by age and subtype. Seroconversion to HA was more frequent in those <20 years old (yo) for influenza A (serosurvey, P = 0.01; immunology, P = 0.02) but not influenza B virus infection. Seroconversion to NA was not influenced by age or virus type. Adults ≥20 yo infected with influenza A viruses were more likely to show NA-only seroconversion compared to children (56% versus 14% [5 to 19 yo] and 0% [0 to 4 yo], respectively). Conversely, children infected with influenza B viruses were more likely than adults to show NA-only seroconversion (88% [0 to 4 yo] and 75% [5 to 19 yo] versus 40% [≥20 yo]). These data indicate a potential role for immunological memory in the dynamics of HA and NA antibody responses. A better mechanistic understanding of this phenomenon will be critical for any future vaccines aimed at eliciting NA immunity.IMPORTANCE Data on the immunologic responses to neuraminidase (NA) is lacking compared to what is available on hemagglutinin (HA) responses, despite growing evidence that NA immunity can be protective and broadly cross-reactive. Understanding these NA responses during natural infection is key to exploiting these properties for improving influenza vaccines. Using two community-acquired influenza cohorts, we showed that the induction of both HA and NA antibodies after infection is influenced by age and subtypes. Such response dynamics suggest the influence of immunological memory, and understanding how this process is regulated will be critical to any vaccine effort targeting NA immunity.


Asunto(s)
Anticuerpos Antivirales/sangre , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Virus de la Influenza A/inmunología , Virus de la Influenza B/inmunología , Gripe Humana/inmunología , Neuraminidasa/inmunología , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Femenino , Humanos , Memoria Inmunológica , Lactante , Recién Nacido , Gripe Humana/sangre , Gripe Humana/epidemiología , Masculino , Nueva Zelanda/epidemiología , Reacción en Cadena de la Polimerasa , Estudios Seroepidemiológicos , Adulto Joven
5.
Regul Toxicol Pharmacol ; 127: 105075, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34728330

RESUMEN

Next generation Risk Assessment (NGRA) is an exposure-led, hypothesis-driven approach which integrates new approach methodologies (NAMs) to assure safety without generating animal data. This hypothetical skin allergy risk assessment of two consumer products - face cream containing 0.1% coumarin and deodorant containing 1% coumarin - demonstrates the application of our skin allergy NGRA framework which incorporates our Skin Allergy Risk Assessment (SARA) Model. SARA uses Bayesian statistics to provide a human relevant point of departure and risk metric for a given chemical exposure based upon input data that can include both NAMs and historical in vivo studies. Regardless of whether NAM or in vivo inputs were used, the model predicted that the face cream and deodorant exposures were low and high risk respectively. Using only NAM data resulted in a minor underestimation of risk relative to in vivo. Coumarin is a predicted pro-hapten and consequently, when applying this mechanistic understanding to the selection of NAMs the discordance in relative risk could be minimized. This case study demonstrates how integrating a computational model and generating bespoke NAM data in a weight of evidence framework can build confidence in safety decision making.


Asunto(s)
Teorema de Bayes , Cosméticos/toxicidad , Cumarinas/toxicidad , Dermatitis por Contacto/patología , Modelos Teóricos , Alternativas a las Pruebas en Animales , Técnicas de Cultivo de Célula , Sistema Enzimático del Citocromo P-450/efectos de los fármacos , Hígado/efectos de los fármacos , Medición de Riesgo , Pruebas de Irritación de la Piel
6.
Community Dent Health ; 36(3): 187-189, 2019 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-31436924

RESUMEN

OBJECTIVE: To evaluate the feasibility of collecting and analyzing saliva samples from dental practices and patients' homes for biochemical verification of tobacco use status. BASIC RESEARCH DESIGN: Sub-study within single-arm, multi-center, longitudinal clinical study. CLINICAL SETTING: Dental practices in the South Central region of the United States National Dental Practice-Based Research Network and patients' homes. PARTICIPANTS: Fifty-five patients recruited from 30 dental practices. INTERVENTIONS: Participants in the sub-study were instructed on saliva collection for cotinine analysis in dental practices where they enrolled in the primary study. Saliva was collected at the practices and then from patients' homes. MAIN OUTCOME MEASURES: Feasibility for dental practice collection was define as 80% of enrolled participants having analyzable samples. For patients' home collection, feasibility was defined as 70%. RESULTS: Forty-seven samples (i.e., 86% of those enrolled) collected in dental practices were analyzable. Twenty-one samples (i.e. 38% of those enrolled) collected in patients' homes were analyzable. CONCLUSIONS: Collecting saliva samples for cotinine analysis from dental practices, but not from patients' homes, was feasible. Dental practices may provide an advantageous setting for biochemically verifying tobacco use status as part of clinical trials for tobacco cessation.


Asunto(s)
Cotinina , Cese del Hábito de Fumar , Uso de Tabaco , Cotinina/análisis , Atención Odontológica , Estudios de Factibilidad , Femenino , Humanos , Masculino , Saliva/química
7.
Am J Physiol Renal Physiol ; 313(3): F687-F698, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28539334

RESUMEN

The dynamics of propagating myogenic contractions in the wall of the resting ex vivo urinary bladder of the rabbit were characterized by spatiotemporal maps and related to cyclic variation in intravesical pressure (Pves). Patches of propagating contractions (PPCs) enlarged and involuted in near synchrony with peaks in Pves [mean 3.85 ± 0.3 cycles per minute (cpm)] and were preceded by regions of stretch. The maximum area of the bladder undergoing contraction (55.28 ± 2.65%) and the sizes of individual PPCs (42.61 ± 1.65 mm2) coincided with the peak in Pves PPCs originated and propagated within temporary patch domains (TPDs) and comprised groups of nearly synchronous cyclic propagating individual contractions (PICs). The TPDs were located principally along the vertical axis of the anterior surface of the bladder. The sites of origin of PICs within PPCs were inconsistent, consecutive contractions often propagating in opposite directions along linear maps of strain rate. Similar patterns of movement occurred in areas of the anterior bladder wall that had been stripped of mucosa. Pves varied cyclically with area of contraction and with the indices of aggregation of PPCs, indicating that they grew by peripheral enlargement and collision without annihilation. The synchronization of PICs within PPCs was sometimes lost, uncoordinated PICs then occurring irregularly (between 4 and 20 cpm) having little effect on Pves We postulate that the formation and involution of PPCs within a TPD resulted from cyclic variation in excitation that increased the incidence and distance over which component PICs propagated.


Asunto(s)
Contracción Muscular , Músculo Liso/inervación , Periodicidad , Vejiga Urinaria/inervación , Administración Intravesical , Animales , Procesamiento de Imagen Asistido por Computador , Técnicas In Vitro , Modelos Lineales , Reconocimiento de Normas Patrones Automatizadas , Presión , Conejos , Cloruro de Sodio/administración & dosificación , Factores de Tiempo , Transductores de Presión , Grabación en Video
8.
Clin Exp Immunol ; 187(1): 113-123, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27667787

RESUMEN

Tolerogenic dendritic cells (tolDC) are a new immunotherapeutic tool for the treatment of rheumatoid arthritis (RA) and other autoimmune disorders. We have established a method to generate stable tolDC by pharmacological modulation of human monocyte-derived DC. These tolDC exert potent pro-tolerogenic actions on CD4+ T cells. Lack of interleukin (IL)-12p70 production is a key immunoregulatory attribute of tolDC but does not explain their action fully. Here we show that tolDC express transforming growth factor (TGF)-ß1 at both mRNA and protein levels, and that expression of this immunoregulatory cytokine is significantly higher in tolDC than in mature monocyte-derived DC. By inhibiting TGF-ß1 signalling we demonstrate that tolDC regulate CD4+ T cell responses in a manner that is at least partly dependent upon this cytokine. Crucially, we also show that while there is no significant difference in expression of TGF-ßRII on CD4+ T cells from RA patients and healthy controls, RA patient CD4+ T cells are measurably less responsive to TGF-ß1 than healthy control CD4+ T cells [reduced TGF-ß-induced mothers against decapentaplegic homologue (Smad)2/3 phosphorylation, forkhead box protein 3 (FoxP3) expression and suppression of (IFN)-γ secretion]. However, CD4+ T cells from RA patients can, nonetheless, be regulated efficiently by tolDC in a TGF-ß1-dependent manner. This work is important for the design and development of future studies investigating the potential use of tolDC as a novel immunotherapy for the treatment of RA.


Asunto(s)
Artritis Reumatoide/terapia , Linfocitos T CD4-Positivos/inmunología , Células Dendríticas/inmunología , Tolerancia Inmunológica , Inmunoterapia/métodos , Factor de Crecimiento Transformador beta1/metabolismo , Artritis Reumatoide/inmunología , Células Cultivadas , Colecalciferol/farmacología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/trasplante , Dexametasona/farmacología , Factores de Transcripción Forkhead/metabolismo , Humanos , Inmunomodulación , Interleucina-12/genética , Interleucina-12/metabolismo , Activación de Linfocitos , Proteína Smad2/metabolismo
9.
Mol Psychiatry ; 21(5): 680-5, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26260493

RESUMEN

We asked whether brain connectomics can predict response to treatment for a neuropsychiatric disorder better than conventional clinical measures. Pre-treatment resting-state brain functional connectivity and diffusion-weighted structural connectivity were measured in 38 patients with social anxiety disorder (SAD) to predict subsequent treatment response to cognitive behavioral therapy (CBT). We used a priori bilateral anatomical amygdala seed-driven resting connectivity and probabilistic tractography of the right inferior longitudinal fasciculus together with a data-driven multivoxel pattern analysis of whole-brain resting-state connectivity before treatment to predict improvement in social anxiety after CBT. Each connectomic measure improved the prediction of individuals' treatment outcomes significantly better than a clinical measure of initial severity, and combining the multimodal connectomics yielded a fivefold improvement in predicting treatment response. Generalization of the findings was supported by leave-one-out cross-validation. After dividing patients into better or worse responders, logistic regression of connectomic predictors and initial severity combined with leave-one-out cross-validation yielded a categorical prediction of clinical improvement with 81% accuracy, 84% sensitivity and 78% specificity. Connectomics of the human brain, measured by widely available imaging methods, may provide brain-based biomarkers (neuromarkers) supporting precision medicine that better guide patients with neuropsychiatric diseases to optimal available treatments, and thus translate basic neuroimaging into medical practice.


Asunto(s)
Encéfalo/fisiopatología , Terapia Cognitivo-Conductual , Conectoma , Fobia Social/fisiopatología , Fobia Social/terapia , Adolescente , Adulto , Terapia Cognitivo-Conductual/métodos , Femenino , Humanos , Modelos Logísticos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/fisiopatología , Fobia Social/diagnóstico , Pronóstico , Descanso , Sensibilidad y Especificidad , Resultado del Tratamiento , Adulto Joven
10.
Am J Physiol Gastrointest Liver Physiol ; 311(6): G1064-G1075, 2016 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-27765760

RESUMEN

We used spatiotemporal mapping of strain rate to determine the direction of propagation and amplitudes of the longitudinal and circumferential components of antrocorporal (AC) contractions and fundal contractions in the rat stomach maintained ex vivo and containing a volume of fluid that was within its normal functional capacity. In the region of the greater curvature the longitudinal and circular components of AC contractions propagated synchronously at right angles to the arciform geometric axis of the stomach. However, the configuration of AC contractions was U shaped, neither the circular nor the longitudinal component of contractions being evident in the upper proximal corpus. Similarly, in the distal upper antrum of some preparations, circumferential components propagated more rapidly than longitudinal components. Ongoing "high-frequency, low-amplitude myogenic contractions" were identified in the upper proximal gastric corpus and on the anterior and posterior wall of the fundus. The amplitudes of these contractions were modulated in the occluded stomach by low-frequency pressure waves that occurred spontaneously. Hence the characteristics of phasic contractions vary regionally in the antrum and corpus and a previously undescribed high-frequency contractile component was identified in the proximal corpus and fundus, the latter being modulated in synchrony with cyclic variation in intrafundal pressure in the occluded fundus.


Asunto(s)
Electromiografía/métodos , Contracción Muscular , Imagen Óptica/métodos , Estómago/fisiología , Animales , Femenino , Masculino , Ratas , Ratas Sprague-Dawley , Estómago/inervación
11.
Ann Rheum Dis ; 75(5): 899-907, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-25923217

RESUMEN

OBJECTIVE: A population of synovial inflammatory dendritic cells (infDCs) has recently been identified in rheumatoid arthritis (RA) and is thought to be monocyte-derived. Here, we investigated the role and source of granulocyte macrophage-colony-stimulating factor (GM-CSF) in the differentiation of synovial infDC in RA. METHODS: Production of GM-CSF by peripheral blood (PB) and synovial fluid (SF) CD4+ T cells was assessed by ELISA and flow cytometry. In vitro CD4+ T-cell polarisation experiments were performed with T-cell activating CD2/CD3/CD28-coated beads in the absence or presence of pro-Th1 or pro-Th17 cytokines. CD1c+ DC and CD16+ macrophage subsets were flow-sorted and analysed morphologically and functionally (T-cell stimulatory/polarising capacity). RESULTS: RA-SF CD4+ T cells produced abundant GM-CSF upon stimulation and significantly more than RA-SF mononuclear cells depleted of CD4+ T cells. GM-CSF-producing T cells were significantly increased in RA-SF compared with non-RA inflammatory arthritis SF, active RA PB and healthy donor PB. GM-CSF-producing CD4+ T cells were expanded by Th1-promoting but not Th17-promoting conditions. Following coculture with RA-SF CD4+ T cells, but not healthy donor PB CD4+ T cells, a subpopulation of monocytes differentiated into CD1c+ infDC; a process dependent on GM-CSF. These infDC displayed potent alloproliferative capacity and enhanced GM-CSF, interleukin-17 and interferon-γ production by CD4+ T cells. InfDC with an identical phenotype to in vitro generated cells were significantly enriched in RA-SF compared with non-RA-SF/tissue/PB. CONCLUSIONS: We demonstrate a therapeutically tractable feedback loop of GM-CSF secreted by RA synovial CD4+ T cells promoting the differentiation of infDC with potent capacity to induce GM-CSF-producing CD4+ T cells.


Asunto(s)
Artritis Reumatoide/inmunología , Linfocitos T CD4-Positivos/inmunología , Células Dendríticas/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Antígenos CD1/análisis , Técnicas de Cocultivo , Citocinas/biosíntesis , Glicoproteínas/análisis , Factor Estimulante de Colonias de Granulocitos y Macrófagos/biosíntesis , Humanos , Inmunofenotipificación , Receptores de Lipopolisacáridos/análisis , Macrófagos/inmunología , Monocitos/inmunología , Osteoartritis/inmunología , Líquido Sinovial/inmunología , Células TH1/inmunología
12.
Pharmacopsychiatry ; 49(2): 62-5, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26838118

RESUMEN

INTRODUCTION: In schizophrenia early treatment may prevent disorder onset, or at least minimize its impact, suggesting possible neuroprotective properties of antipsychotics. The present study investigates the effects of chronic treatment with the atypical antipsychotic, risperidone, on locomotor sensitization in the subchronic phencyclidine-treated rat. METHODS: Rats were treated with phencyclidine sub-chronically (2 mg/kg bi-daily for one week followed by a one-week wash-out period) or vehicle. Half of the phencyclidine group was concurrently treated with risperidone (0.5 mg/kg IP) twice daily for 15 days, beginning 3 days before the start of phencyclidine administration. 6 weeks after treatment all rats were injected with a phencyclidine-challenge (3.2 mg/kg) and immediately after their locomotor activity measured for 20 min. RESULTS: Co-administration of risperidone at the time of phencyclidine administration significantly reduced the phencyclidine-challenge locomotor effect administered 6 weeks later. DISCUSSION: These results demonstrate that concurrent risperidone is neuroprotective, and clearly suggests its functionality can be translated to a clinical setting for treating the so-called prodrome.


Asunto(s)
Sensibilización del Sistema Nervioso Central/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Fenciclidina/administración & dosificación , Fenciclidina/antagonistas & inhibidores , Risperidona/administración & dosificación , Risperidona/farmacología , Animales , Masculino , Fármacos Neuroprotectores/administración & dosificación , Fenciclidina/farmacología , Ratas
13.
Br J Cancer ; 112(2): 319-28, 2015 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-25405854

RESUMEN

BACKGROUND: Regulatory T cells (Treg) are enriched in human colorectal cancer (CRC) where they suppress anti-tumour immunity. The chemokine receptor CCR5 has been implicated in the recruitment of Treg from blood into CRC and tumour growth is delayed in CCR5-/- mice, associated with reduced tumour Treg infiltration. METHODS: Tissue and blood samples were obtained from patients undergoing resection of CRC. Tumour-infiltrating lymphocytes were phenotyped for chemokine receptors using flow cytometry. The presence of tissue chemokines was assessed. Standard chemotaxis and suppression assays were performed and the effects of CCR5 blockade were tested in murine tumour models. RESULTS: Functional CCR5 was highly expressed by human CRC infiltrating Treg and CCR5(high) Treg were more suppressive than their CCR5(low) Treg counterparts. Human CRC-Treg were more proliferative and activated than other T cells suggesting that local proliferation could provide an alternative explanation for the observed tumour Treg enrichment. Pharmacological inhibition of CCR5 failed to reduce tumour Treg infiltration in murine tumour models although it did result in delayed tumour growth. CONCLUSIONS: CCR5 inhibition does not mediate anti-tumour effects as a consequence of inhibiting Treg recruitment. Other mechanisms must be found to explain this effect. This has important implications for anti-CCR5 therapy in CRC.


Asunto(s)
Antineoplásicos/farmacología , Antagonistas de los Receptores CCR5/farmacología , Neoplasias Colorrectales/inmunología , Ciclohexanos/farmacología , Linfocitos T Reguladores/inmunología , Triazoles/farmacología , Animales , Línea Celular Tumoral , Proliferación Celular , Quimiocina CCL4/metabolismo , Quimiotaxis de Leucocito , Neoplasias Colorrectales/tratamiento farmacológico , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Maraviroc , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/inmunología , Ratones Endogámicos BALB C , Trasplante de Neoplasias , Receptores CCR5/metabolismo , Linfocitos T Reguladores/metabolismo
14.
Plant Dis ; 99(3): 415, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30699715

RESUMEN

In 2011, bacterial blight of arugula (Eruca vesicaria subsp. sativa; cv. Roquette) was observed in organically grown plants under overhead irrigation in a field near Delano, MN. Approximately 80 to 100% of each planting was affected, with greater rates of infection occurring after periods of high humidity. Small, water-soaked, angular spots apparent on both sides of the leaves comprised the initial symptoms, which sometimes expanded and coalesced. Lesions maintained a dark water-soaked appearance or dried and turned a brown/tan color. Additionally, some lesions were outlined by a purple margin. Blue-green fluorescent pseudomonads were isolated consistently on King's Medium B agar (KMB) from symptomatic leaf tissue surface-disinfested with sodium hypochlorite (0.525%). The isolates nucleated ice and produced levan. Isolates were oxidase and arginine dihydrolase negative. They did not rot potato slices but did induce a hypersensitive reaction in tobacco (Nicotiana tabacum cv. Samsun). These data indicated that the bacteria belonged to Lelliott's LOPAT group 1 (2). DNA fragment banding patterns generated by amplifying DNA of the arugula isolates using repetitive extragenic palindromic sequence-polymerase chain reaction (rep-PCR) and the BOX A1R primer were identical and nearly identical to the banding patterns of the Pseudomonas cannabina pv. alisalensis (formerly P. syringae pv. alisalensis) (1) strain (CFBP1637) and the pathotype strain (CFBP 6866PT), respectively. Pathogenicity was confirmed on the arugula cv. My Way in two independent experiments, each with three replicate plants per treatment. Four isolates were grown on KMB for 48 h at 27°C, suspended in 0.01M potassium phosphate buffer (pH 7.0), and adjusted to 0.6 optical density at 600 nm (approximately 1 × 108 CFU/ml). Five- to six-week old plants were spray-inoculated until run-off, incubated in a humidity chamber for 48 h, and then placed in a greenhouse at 20 to 25°C for symptom development. For negative and positive control treatments, a similar number of plants each were sprayed with sterile buffer or P. cannabina pv. alisalensis strains CFBP1637 and CFBP 6866PT, respectively. Water-soaked and brown/tan lesions similar to the original symptoms appeared on plants inoculated with the arugula isolates and P. cannabina pv. alisalensis strains 7 to 14 days postinoculation. No symptoms developed on plants treated with sterile buffer. The bacterial strains re-isolated from surface-disinfested symptomatic tissue were identical by rep-PCR to the isolates used to inoculate the plants, thus, confirming Koch's postulates. Identical replicated experiments conducted on broccoli raab indicated that the arugula isolates were also pathogens of broccoli raab (Brassica rapa subsp. rapa, the original host from which P. cannabina pv. alisalensis was isolated). To our knowledge, this is the first report of bacterial blight of crucifers caused by P. cannabina pv. alisalensis in Minnesota. Arugula germplasm is being evaluated for resistance to this pathogen as an acceptable management method for organic cropping systems. References: (1) C. T. Bull et al. Syst. Appl. Microbiol. 33:105, 2010. (2) R. A. Lelliott. J. Appl. Bacteriol. 29:470, 1966.

15.
J Intern Med ; 275(4): 409-17, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24206536

RESUMEN

OBJECTIVE: Patients with chronic fatigue syndrome (CFS) are frequently diagnosed with comorbid postural orthostatic tachycardia syndrome (POTS), suggesting a shared pathogenesis. The aim of this study was to examine the relationship between demographic characteristics, autonomic functioning and fatigue levels amongst CFS patients with and without comorbid POTS. DESIGN AND SETTING: All patients presenting to the CFS Discovery Clinic between 2009 and 2012 completed a 20-min standing task as part of their initial assessment. Heart rate and pulse pressure were recorded at baseline, at 2-min intervals poststanding, at the end of the task and following a recovery period. Average heart rate and pulse pressure variability were calculated from this data. Age, gender, length of illness and self-reported fatigue scores were also recorded. POTS patients were diagnosed by an orthostatic increase in heart rate >30 beats per min, concomitant symptoms of orthostatic intolerance and no orthostatic hypotension. Differences in autonomic functioning between POTS and CFS patients were compared using independent samples t-tests, whilst logistic and linear regressions were performed to examine the contribution of autonomic functioning to task completion and perceived fatigue, respectively. RESULTS: Comorbidity of CFS and POTS (CFS-POTS) was observed in 11% (33/306) of patients. CFS-POTS patients were significantly younger (P < 0.001), had a shorter length of illness (P = 0.034), experienced greater task difficulty (P = 0.002) and were able to stand for significantly shorter periods compared to the CFS-only patients (P < 0.001). CFS-POTS patients experienced significantly lower baseline diastolic blood pressure (P = 0.002), significantly higher heart rate and lower pulse pressures at each standing measurement. Early heart rate changes (P = 0.002) and overall heart rate change (P < 0.001) were significant predictors of completion status, whereas heart rate variability (P < 0.001) and female gender (P < 0.001) were significant predictors of increased perceived task difficulty. CONCLUSIONS: Haemodynamic and demographic differences between CFS-POTS and CFS-only patients suggest that the former group reflects a distinct subgroup of the CFS population. The findings highlight the utility of screening younger patients with fatigue for POTS, and identified heart rate variability as an important marker of fatigue for CFS patients in general.


Asunto(s)
Presión Sanguínea , Síndrome de Fatiga Crónica/fisiopatología , Frecuencia Cardíaca , Síndrome de Taquicardia Postural Ortostática/fisiopatología , Postura , Sistema Nervioso Simpático/fisiopatología , Adulto , Australia/epidemiología , Estudios de Cohortes , Comorbilidad , Síndrome de Fatiga Crónica/diagnóstico , Síndrome de Fatiga Crónica/epidemiología , Femenino , Hemodinámica , Humanos , Masculino , Síndrome de Taquicardia Postural Ortostática/diagnóstico , Síndrome de Taquicardia Postural Ortostática/epidemiología , Prevalencia
16.
Int J Pharm ; 650: 123705, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38110016

RESUMEN

Pharmaceutical tablet formulations combine the active ingredient with processing aids and functional components. This paper evaluates compressibility based predictive models for binary and ternary formulations to establish an acceptable range of tablet compression parameters that satisfy prescribed quality target criteria for tablets including minimum tablet strength and processing constraints such as maximum ejection stress and maximum compaction pressure. The concept of Successful Formulation Window (SFW) is introduced. A methodology is proposed to determine the SFW for a given formulation based on compaction simulator data collected for individual formulation components. The methodology is validated for binary and ternary mixtures and lubricated formulations. The SFW analysis was developed to support tablet formulation design to meet mechanical requirements.


Asunto(s)
Comprimidos , Lubrificación , Presión , Resistencia a la Tracción
17.
Int J Pharm ; 651: 123796, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38190950

RESUMEN

Utilising three artificial intelligence (AI)/machine learning (ML) tools, this study explores the prediction of fill level in inclined linear blenders at steady state by mapping a wide range of bulk powder characteristics to processing parameters. Predicting fill levels enables the calculation of blade passes (strain), known from existing literature to enhance content uniformity. We present and train three AI/ML models, each demonstrating unique predictive capabilities for fill level. These models collectively identify the following rank order of feature importance: RPM, Mixing Blade Region (MB) size, Wall Friction Angle (WFA), and Feed Rate (FR). Random Forest Regression, a machine learning algorithm that constructs a multitude of decision trees at training time and outputs the mode of the classes (classification) or mean prediction (regression) of the individual trees, develops a series of individually useful decision trees. but also allows the extraction of logic and breakpoints within the data. A novel tool which utilises smart optimisation and symbolic regression to model complex systems into simple, closed-form equations, is used to build an accurate reduced-order model. Finally, an Artificial Neural Network (ANN), though less interrogable emerges as the most accurate fill level predictor, with an r2 value of 0.97. Following training on single-component mixtures, the models are tested with a four-component powdered paracetamol formulation, mimicking an existing commercial drug product. The ANN predicts the fill level of this formulation at three RPMs (250, 350 and 450) with a mean absolute error of 1.4%. Ultimately, the modelling tools showcase a framework to better understand the interaction between process and formulation. The result of this allows for a first-time-right approach for formulation development whilst gaining process understanding from fewer experiments. Resulting in the ability to approach risk during product development whilst gaining a greater holistic understanding of the processing environment of the desired formulation.


Asunto(s)
Inteligencia Artificial , Aprendizaje Automático , Redes Neurales de la Computación , Algoritmos , Fenómenos Físicos
18.
J Dairy Sci ; 96(10): 6539-49, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23958020

RESUMEN

Increasing early (<3 mo) nutrient feeding levels and growth rate of dairy calves has been found to increase their milk production potential. The objective of this study was to compare the effect of offering milk diets with or without added carbohydrates and amino acids on calf growth, weaning age, and subsequent growth and milk yield of dairy heifers in their first lactation. Friesian calves born at Massey University (n=57) were selected at random, weighed, and allocated to receive 1 of 3 diets. All calves were fed colostrum from 1 to 3d of age, followed by 4 L of whole milk (WM) per head per day and probiotics between 3 and 18d of age. At 18d of age, calves were weighed to ensure mean body weight (BW); then, at 19 d of age, calves changed diets to 1 of 3 treatments, which reached full treatment rate at 21 d of age. The diets were 4 L/head per day of WM (M); 4 L/head per day of WM plus 200 g of plant carbohydrates (MP); and 4 L/head per day of WM plus 200 g of plant carbohydrates with amino acids (MPA). Calves were weaned upon reaching a BW of 90 kg. During this period, BW, body condition, and hip height and width were measured. The heifers were commingled and grazed on ryegrass and white clover pastures until calving at 23 mo of age, when BW, body condition, and hip height and width were measured again. Milk yield and composition were measured throughout first lactation. At weaning, calves fed MPA had greater mean BW gain, a lower number of days to target BW, and a greater mean hip width gain compared with calves in the M group, although mean gain in hip height did not differ among treatments. Total calf starter intake during the milk period was lower for MPA-fed calves compared with those offered M, mainly due to a shorter milk feeding period required to attain the 90-kg weaning weight, whereas mean daily starter intake and straw intake did not differ. No difference was observed in the calving rate or calving age of heifers in any of the dietary feeding groups. First lactation fat-corrected milk yield, milk fat percentage, and total milk fat and protein yields were greater for animals reared on MP and MPA compared with M. Body weight, hip height and width at parturition, milk protein percentage, somatic cell count, or days in milk did not differ among treatments. Increasing nutrient intake, during the milk feeding period, improved the BW gain of calves and milk production of dairy heifers during first lactation.


Asunto(s)
Aminoácidos/administración & dosificación , Fenómenos Fisiológicos Nutricionales de los Animales , Bovinos/crecimiento & desarrollo , Dieta/veterinaria , Lactancia , Leche/química , Aminoácidos/análisis , Alimentación Animal , Animales , Peso Corporal , Bovinos/fisiología , Ingestión de Energía , Conducta Alimentaria , Femenino , Proteínas de la Leche/análisis , Destete , Aumento de Peso
19.
Poult Sci ; 92(2): 483-91, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23300317

RESUMEN

We report the results of spatiotemporal mapping of the spontaneous actions of component muscles of the gizzard and associated structures in ex vivo preparations with combined superfusion and vascular perfusion. Ongoing spontaneous contraction of cranial and caudal thin muscles occurred at a frequency of 2.2 ± 0.1 cycles per minute. Contractions of M. tenuis craniodorsalis with mean duration of 2.8 ± 0.2 s commenced ventrally adjacent to the distal limit of the proventriculus and progressed dorsally at 2.02 ± 0.03 mm•s(-1) in a concerted front. Near simultaneous contraction of M. tenuis caudoventralis of mean duration of contraction of 4.7 ± 0.7 s commenced dorsally and progressed ventrally at a similar rate (2.1 ± 0.1 mm•s(-1)) and in a similar manner. Contraction of the caudoventralis preceded that of craniodorsalis (mean 1.1 ± 0.15 s). Contraction of the 2 tenuis muscles was synchronous with the first component peak of the cyclic increase in lumen pressure and with distension of the crassus musculature. Contraction of the M. crassus caudodorsalis muscle coincided with the second component peak and was followed by distension of the tenuis musculature. The latter commenced before the relaxation of the tenuis muscles. Contractions of the crassus muscle propagated rapidly at right angles to the orientation of the muscle fibers at a faster velocity than that of the tenuis musculature. The durations of the component peaks in lumen pressure indicated that the duration of crassus contraction was similar to that of the tenuis musculature.


Asunto(s)
Pollos/fisiología , Molleja de las Aves/fisiología , Contracción Muscular , Animales , Estimulación Eléctrica , Técnicas In Vitro , Imagen de Perfusión , Presión , Nervio Vago/fisiología
20.
Occup Health Sci ; : 1-36, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37359456

RESUMEN

Wellness involves physical, emotional, behavioral, social, and spiritual dimensions. A climate for wellness exists at both the psychological and organizational levels, consisting of individual and shared perceptions of policies, structures, and managerial behavior that support or promote employee wellbeing. This study explored the associations between psychological and organizational wellness climate and the effectiveness of a team health promotion training on employees' perceived physical and mental wellbeing and substance use. Employees from 45 small businesses completed self-report measures of wellness climate, wellbeing, positive unwinding behavior, work-family conflict, job stress, drug use, and alcohol use, assessed before, and one and six months after, attending either of two types of onsite health promotion training. Team Awareness training targeted improvements in the social climate at work. Healthy Choices training targeted individual health behavior. A control group did not receive training until after the study. Businesses were randomly assigned to conditions and data were analyzed using multi-level modeling. Models that included wellness climate as a mediator fit the data significantly better than models without climate as a mediator. Team Awareness participants showed greater improvements in wellness climate and wellbeing compared to the control group. Healthy Choices participants showed no changes in climate and no mediation effects of climate. Health promotion efforts may be enhanced by including wellness climate as a target in program design at multiple levels.

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