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1.
Curr Res Food Sci ; 7: 100632, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38021262

RESUMEN

Animal-based food products, such as meat and dairy, contribute the most to greenhouse gas emissions in the food sector. This, coupled with the demonstrably worsening climate crisis, means that there needs to be a shift to more sustainable alternatives in the form of plant-based foods. In particular, the plant-based cheese alternative industry is relevant, as the products lack critical functionalities and nutrition compared to their dairy-based counterparts. Waxy starch, plant-protein isolate, and coconut oil were combined to create a novel high-protein (18% w/w) plant-based cheese alternative. We determined that when using native waxy starch, we can enhance its existing viscoelastic properties by modulating gelatinization through adding plant protein and fat. Texture profile analysis indicated that the cheese analogues could reach hardness levels of 15-90N, which allowed samples to be tailored to a broader range of dairy products. We determined that plant proteins and fat can behave as particulate fillers, enhance network strength, and create strategic junction points during starch retrogradation. The degree of melt and stretch of the high-protein plant-based analogues were 2-3 times greater than those observed for commercial plant-based cheese alternatives and significantly more similar to dairy cheese. The rheological melting kinetics saw that the high-protein plant-based cheese alternative displayed more viscous properties with increasing temperature. Tan δ (G"/G') at 80 °C was used as an indicator for sample meltability where, values ≥1 indicate better melt and more viscous systems. The high-protein plant-based cheese alternative reached Tan δ values upwards to 0.7, whereas commercial plant-based cheese alternatives only reached tan δ values around 0.1. Ultimately, the novel high-protein plant-based cheese alternative demonstrates the use of simple ingredients to form complex food systems.

2.
Int J Tuberc Lung Dis ; 24(11): 1145-1150, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-33172521

RESUMEN

TB is one of the top 10 causes of death worldwide and the leading cause of death from a single infectious agent. Decreasing the length of time for TB treatment is an important step towards the goal of reducing mortality. Mechanistic in silico modelling can provide us with the tools to explore gaps in our knowledge, with the opportunity to model the complicated within-host dynamics of the infection, and simulate new treatment strategies. Significant insight has been gained using this form of modelling when applied to other diseases - much can be learned in infection research from these advances.


Asunto(s)
Tuberculosis , Simulación por Computador , Humanos , Tuberculosis/tratamiento farmacológico
3.
BMC Infect Dis ; 20(1): 482, 2020 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-32640998

RESUMEN

BACKGROUND: Persistent high-risk human papillomavirus (HPV) infection is endorsed by the World Health Organization as an intermediate endpoint for evaluating HPV vaccine effectiveness/efficacy. There are different approaches to estimate the vaccine effectiveness/efficacy against persistent HPV infections. METHODS: We performed a systematic literature search in Pubmed to identify statistical approaches that have been used to estimate the vaccine effectiveness/efficacy against persistent HPV infections. We applied these methods to data of a longitudinal observational study to assess their performance and compare the obtained vaccine effectiveness (VE) estimates. RESULTS: Our literature search identified four approaches: the conditional exact test for comparing two independent Poisson rates using a binomial distribution, Generalized Estimating Equations for Poisson regression, Prentice Williams and Peterson total time (PWP-TT) and Cox proportional hazards regression. These approaches differ regarding underlying assumptions and provide different effect measures. However, they provided similar effectiveness estimates against HPV16/18 and HPV31/33/45 persistent infections in a cohort of young women eligible for routine HPV vaccination (range VE 93.7-95.1% and 60.4-67.7%, respectively) and seemed robust to violations of underlying assumptions. CONCLUSIONS: As the rate of subsequent infections increased in our observational cohort, we recommend PWP-TT as the optimal approach to estimate the vaccine effectiveness against persistent HPV infections in young women. Confirmation of our findings should be undertaken by applying these methods after longer follow-up in our study, as well as in different populations.


Asunto(s)
Papillomavirus Humano 18/inmunología , Papillomavirus Humano 31/inmunología , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/inmunología , Vacunas contra Papillomavirus/uso terapéutico , Vacunación , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Humanos , Inmunogenicidad Vacunal , Estudios Longitudinales , Infecciones por Papillomavirus/virología , Prevalencia , Resultado del Tratamiento , Adulto Joven
4.
Br J Anaesth ; 120(2): 308-316, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29406180

RESUMEN

BACKGROUND: Recent studies have concluded that i.v. dexamethasone can prolong the duration of peripheral nerve blockade. We hypothesized that a 4 mg dose would equally prolong the duration of psoas compartment blocks (PCBs) when compared with 8 mg, and that both doses would prolong the duration when compared with placebo. METHODS: This was a prospective, randomized, placebo-controlled, dose-dependent, equivalency trial with 115 patients undergoing total hip arthroplasty. The patients received a PCB. Subsequently, 15 patients received i.v. normal saline (placebo), 50 patients received i.v. dexamethasone 4 mg, and 50 patients received i.v. dexamethasone 8 mg. The primary outcome was the duration in hours of PCB, determined by serial pinprick assessments. Secondary outcomes included pain scores, time to first analgesic, and opioid consumption. An intention-to-treat-analysis (ITA) and per-protocol analysis (PPA) were performed. RESULTS: The ITA showed that block duration in the 4 and 8 mg groups was equivalent [mean (standard deviation), 18.5 h (8.0) vs 18.1 h (7.1)]. However, neither group differed from placebo [19.6 h (6.7), (4 mg vs placebo), P=0.97; (8 mg vs placebo), P=0.77)]. Postoperative pain scores and opioid consumption were not different between groups. Time to first analgesic was not different between the 4 and 8 mg groups, or the 4 mg and placebo groups. The 8 mg group, however, had a longer time to first analgesic (median of 533 vs 432 min, P=0.047) when compared with placebo, although the significance was not observed in the PPA (P=0.058). CONCLUSIONS: I.V. dexamethasone did not prolong PCB when duration was objectively assessed, or decrease total opioid consumption. However, dexamethasone 8 mg prolonged the time to first analgesic. CLINICAL TRIAL REGISTRATION: NCT 02464176.


Asunto(s)
Dexametasona/uso terapéutico , Bloqueo Nervioso/métodos , Dimensión del Dolor/efectos de los fármacos , Administración Intravenosa , Anciano , Analgésicos Opioides/administración & dosificación , Artroplastia de Reemplazo de Cadera/métodos , Dexametasona/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/prevención & control , Estudios Prospectivos , Músculos Psoas , Resultado del Tratamiento
5.
Med Vet Entomol ; 30(3): 247-52, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27352139

RESUMEN

The impact of deltamethrin-impregnated cloth targets on Stegomyia polynesiensis (= Aedes polynesiensis) (Marks) (Diptera: Culicidae) was assessed under laboratory and semi-field settings in French Polynesia. Stegomyia polynesiensis females were released into small laboratory cages and large field cages containing either a deltamethrin-treated or an untreated navy blue cloth, and mosquito knock-down and mortality were assessed. The 24-h mortality rate in mosquitoes exposed to the insecticide-treated target in small cages was 98.0%. These mosquitoes also demonstrated significantly higher levels of knock-down than those exposed to the untreated target. Mortality in field cages was assessed at 24 and 48 h. The 24-h mortality rate in mosquitoes exposed to the control target was 31.2%, whereas that in those exposed to the deltamethrin-treated target was 54.3%. The 48-h mortality rate was also elevated in mosquitoes exposed to the deltamethrin-treated target, but this result did not differ significantly from that observed in mosquitoes exposed to the control target. The significant suppression of female S. polynesiensis by deltamethrin-treated resting targets in this study indicates that these targets could play a role in the control of an important disease vector in the South Pacific region.


Asunto(s)
Aedes , Control de Insectos/normas , Insecticidas , Nitrilos , Piretrinas , Animales , Femenino , Polinesia , Análisis de Supervivencia
6.
Ultrasound Obstet Gynecol ; 47(1): 28-37, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25766776

RESUMEN

OBJECTIVES: To determine the accuracy of ultrasound in the diagnosis of a tubal ectopic pregnancy in the absence of an obvious extrauterine embryo. METHODS: This was a systematic review conducted in accordance with the PRISMA statement and registered with PROSPERO. We searched MEDLINE, EMBASE and The Cochrane Library for relevant citations from database inception to July 2014. Studies were selected in a two-stage process and their data extracted by two reviewers. Accuracy measures were calculated for each ultrasound sign, i.e. empty uterus, pseudosac, adnexal mass and free fluid in the pouch of Douglas, alone and in various combinations. Individual study estimates were plotted in summary receiver-operating characteristics curves and forest plots for examination of heterogeneity. The quality of included studies was assessed. RESULTS: Thirty-one studies including 5858 women were selected from 19,959 citations. Following meta-analysis, an empty uterus on ultrasound was found to predict an ectopic pregnancy with a sensitivity of 81.1% (95% CI, 42.1-96.2%) and specificity of 79.5% (95% CI, 68.9-87.1%). The corresponding performance of the pseudosac, adnexal mass and free fluid were: 5.5% (95% CI, 3.3-9.0%) and 94.2% (95% CI, 75.9-98.8%); 63.5% (95% CI, 48.5-76.3%) and 91.4% (95% CI, 83.6-95.7%); and 47.2% (95% CI, 33.2-61.7%) and 92.3% (95% CI, 85.6-96.0%), respectively. CONCLUSION: Visualization of an empty uterus, adnexal mass, free fluid or a pseudosac has poor sensitivity for the diagnosis of a tubal pregnancy when an obvious extrauterine embryo is absent, but it has good specificity. We can therefore infer that ultrasound is more useful for 'ruling in' a tubal pregnancy than 'ruling out' one. However, the findings were limited by the poor quality of some included studies and heterogeneity in the index test and reference standard.


Asunto(s)
Embarazo Tubario/diagnóstico por imagen , Femenino , Humanos , Embarazo , Primer Trimestre del Embarazo , Embarazo Tubario/diagnóstico , Sensibilidad y Especificidad , Ultrasonografía Prenatal
7.
Ultrasound Obstet Gynecol ; 46(2): 142-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25393076

RESUMEN

OBJECTIVES: To evaluate the diagnostic accuracy of ultrasound in predicting the location of an intrauterine pregnancy before visualization of the yolk sac is possible. METHODS: This was a systematic review conducted in accordance with the PRISMA statement and registered with PROSPERO. We searched MEDLINE, EMBASE and The Cochrane Library for relevant citations. Studies were selected in a two-stage process and their data extracted by two reviewers. Accuracy measures were calculated for each ultrasound sign, i.e. gestational sac, double decidual sac sign, intradecidual sign, chorionic rim sign and yolk sac. Individual study estimates were plotted in summary receiver-operating characteristics curves and forest plots for examination of heterogeneity. The quality of included studies was assessed. RESULTS: Seventeen studies including 2564 women were selected from 19 959 potential papers. Following meta-analysis, the presence of a gestational sac on ultrasound examination was found to predict an intrauterine pregnancy with a sensitivity of 52.8% (95% CI, 38.2-66.9%) and specificity of 97.6% (95% CI, 94.3-99.0%). The corresponding performance of the double decidual sac sign, intradecidual sign, chorionic rim sign and yolk sac were: 81.8% (95% CI, 68.1-90.4%) and 97.3% (95% CI, 76.1-99.8%); 66.1% (95% CI, 58.9-72.8%) and 100% (95% CI, 91.0-100%); 79.9% (95% CI, 73.0-85.7%) and 97.1% (95% CI, 89.9-99.6%); and 42.2% (95% CI, 27.7-57.9%) and 100% (95% CI, 54.1-100%), respectively. CONCLUSION: Visualization of a gestational sac, double decidual sac sign, intradecidual sign or chorionic rim sign increases the probability of an intrauterine pregnancy but is not as accurate for diagnosis as the detection of the yolk sac. However, the findings were limited by the small number and poor quality of the studies included and heterogeneity in the index test and reference standard.


Asunto(s)
Saco Gestacional/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Saco Vitelino/diagnóstico por imagen , Decidua/diagnóstico por imagen , Femenino , Humanos , Embarazo , Primer Trimestre del Embarazo , Embarazo Ectópico/diagnóstico por imagen , Embarazo Ectópico/prevención & control
9.
Leukemia ; 29(1): 177-87, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24791856

RESUMEN

Historically, our understanding of mechanisms underlying human leukemogenesis are inferred from genetically engineered mouse models. Relatively, few models that use primary human cells recapitulate the full leukemic transformation as assayed in xenografts and myeloid transformation is infrequent. We report a humanized experimental leukemia model where xenografts develop aggressive acute myeloid leukemia (AML) with disseminated myeloid sarcomas within 4 weeks following transplantation of cord blood transduced with vectors expressing BCR-ABL1 and a dominant-negative isoform of IKAROS, Ik6. Ik6 induced transcriptional programs in BCR-ABL1-transduced progenitors that contained repressed B-cell progenitor programs, along with strong stemness, proliferation and granulocyte-monocytic progenitor (GMP) signatures-a novel combination not induced in control groups. Thus, wild-type IKAROS restrains stemness properties and has tumor suppressor activity in BCR-ABL1-initiated leukemia. Although IKAROS mutations/deletions are common in lymphoid transformation, they are found also at low frequency in AML that progress from a prior myeloproliferative neoplasm (MPN) state. Our experimental system provides an excellent model to gain insight into these rare cases of AML transformation and the properties conferred by IKAROS loss of function as a secondary mutation. More generally, our data points to the importance of deregulated stemness/lineage commitment programs in human myeloid leukemogenesis.


Asunto(s)
Proteínas de Fusión bcr-abl/metabolismo , Genes Dominantes , Factor de Transcripción Ikaros/metabolismo , Leucemia Mieloide Aguda/etiología , Línea Celular , Proliferación Celular , Xenoinjertos , Humanos , Factor de Transcripción Ikaros/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología
10.
J Med Entomol ; 50(4): 723-30, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23926769

RESUMEN

Understanding the mating competitiveness of male mosquitoes in field settings is essential to programs relying on the mass release of modified male mosquitoes, yet studies on male ecology have been hampered by the lack of a convenient trapping method. An existing promising method makes use of the innate attraction of males to female flight tones. Here, we present laboratory, greenhouse, and field experiments on the efficacy of sound traps for the collection of Aedes aegypti (L.) and Aedes polynesiensis Marks, and laboratory experiments with Ae. aegypti on the effects of male age, size, and mating status on responsiveness to a range of frequencies. Age and mating status influenced the overall responsiveness to sound, whereas male size did not. There were no interactions between these factors and sound frequency. A Centers for Disease Control and Prevention miniature light trap modified to produce a tone of 465 Hz collected 76.2% of Ae. aegypti males in laboratory cages, and 49.7% of males in a greenhouse enclosure. In two sets of experiments in laboratory cages, 50.8 and 46.5% of male Ae. polynesiensis were captured with a trap producing a tone of 440 Hz. In the field, CDC miniature light traps or BG-Sentinel traps fitted with a portable speaker producing tones of 440 or 465 Hz captured significantly more male Ae. polynesiensis when placed near a male swarm than did traps that did not produce sound. When the trap was placed at a distance of 16.5 m from the nearest swarm, there was no significant difference in the number of males caught between control and sound-producing traps. The numbers of Ae. aegypti males captured were low under all circumstances in the field.


Asunto(s)
Aedes/fisiología , Control de Mosquitos/métodos , Conducta Sexual Animal , Estimulación Acústica , Animales , Percepción Auditiva , Femenino , Masculino
11.
J Med Entomol ; 50(4): 740-7, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23926771

RESUMEN

We characterize the swarming behavior of male Aedes polynesiensis (Marks) in American Samoa. Instead of swarming around a blood host, males used the base of certain trees as a marker. Repeated sampling proved nondestructive and allowed us to investigate the impact of static (e.g., tree species) and dynamic (e.g., barometric pressure) characters on the likelihood of swarm presence and intensity. Tree circumference and oviposition activity (number of Ae. polynesiensis reared from oviposition cups) were significant positive predictors of the number of males in a swarm. Tree circumference and diameter were significantly positively associated, and canopy height was significantly negatively associated, with swarm occurrence. Comparisons between males swarming early and late during the swarming period allowed for insight into swarm composition in terms of male size and the amount of putative fluid (e.g., nectar) in the crop, indicators of energetic reserves. Males collected during the late period had significantly larger wings and less crop contents than did males of the early cohort. Because the ecology of male Ae. polynesiensis remains understudied, we consider how the current results could facilitate further studies related to applied autocidal strategies as well as the evolution of host-based mating behavior.


Asunto(s)
Aedes/fisiología , Insectos Vectores/fisiología , Aedes/anatomía & histología , Presión del Aire , Samoa Americana , Animales , Metabolismo Energético , Femenino , Filariasis/transmisión , Humanos , Masculino , Control de Mosquitos , Dinámica Poblacional , Árboles , Wuchereria bancrofti/fisiología
12.
Vaccine ; 31(51): 6136-43, 2013 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-23850416

RESUMEN

OBJECTIVE: The investigational AS04-adjuvanted herpes simplex virus type 2 (HSV-2) glycoprotein D (gD2) subunit prophylactic vaccine ('HSV vaccine'; GlaxoSmithKline Vaccines) has been shown to be well tolerated in adults, but limited data exist for pre-teen and adolescent girls, a likely target population. The primary objective of this study was to compare the occurrence of serious adverse events (SAEs) over 12 months between HSV vaccine recipients and saline recipients (placebo control group) in pre-teen and adolescent girls. The immunogenicity of the HSV vaccine was also assessed. METHODS: Healthy girls aged 10-17 years, stratified by age (10-15 years; 16-17 years), were randomised 2:1:1 to receive the HSV vaccine, a hepatitis A vaccine (Havrix™; HAV control) or placebo (saline) according to a 0-, 1-, 6-month schedule. Participants and study personnel not involved in the preparation or administration of vaccines were blinded to treatment. Safety and immunogenicity analyses were performed overall and by age (10-15 years; 16-17 years) and HSV serostatus. RESULTS: No statistically significant difference in the percentage of subjects with SAEs was observed between the HSV and saline group, or between the HSV and pooled control (HAV and saline) groups. The HSV vaccine was well tolerated, although a higher incidence of solicited local symptoms was observed in the HSV group than in the control group. Neither age nor HSV serostatus at the time of study entry had an impact on the safety profile of this vaccine. The HSV vaccine was immunogenic regardless of pre-vaccination HSV serostatus. Higher anti-gD geometric mean concentrations were observed in HSV-1 seropositive participants than in HSV-1 seronegative participants. CONCLUSION: The HSV vaccine had an acceptable safety profile, and was well tolerated and immunogenic when administered to girls aged 10-17 years regardless of age or HSV pre-vaccination serostatus.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Herpes Genital/prevención & control , Vacunas contra Herpesvirus/efectos adversos , Vacunas contra Herpesvirus/inmunología , Adolescente , Niño , Método Doble Ciego , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Femenino , Herpes Genital/inmunología , Herpesvirus Humano 2/inmunología , Vacunas contra Herpesvirus/administración & dosificación , Humanos , Placebos/administración & dosificación , Vacunas de Subunidad/administración & dosificación , Vacunas de Subunidad/efectos adversos , Vacunas de Subunidad/inmunología , Proteínas del Envoltorio Viral/inmunología
13.
Artículo en Inglés | MEDLINE | ID: mdl-23679478

RESUMEN

Adaptive networks, which combine topological evolution of the network with dynamics on the network, are ubiquitous across disciplines. Examples include technical distribution networks such as road networks and the internet, natural and biological networks, and social science networks. These networks often interact with or depend upon other networks, resulting in coupled adaptive networks. In this paper we study susceptible-infected-susceptible (SIS) epidemic dynamics on coupled adaptive networks, where susceptible nodes are able to avoid contact with infected nodes by rewiring their intranetwork connections. However, infected nodes can pass the disease through internetwork connections, which do not change with time: The dependencies between the coupled networks remain constant. We develop an analytical formalism for these systems and validate it using extensive numerical simulation. We find that stability is increased by increasing the number of internetwork links, in the sense that the range of parameters over which both endemic and healthy states coexist (both states are reachable depending on the initial conditions) becomes smaller. Finally, we find a new stable state that does not appear in the case of a single adaptive network but only in the case of weakly coupled networks, in which the infection is endemic in one network but neither becomes endemic nor dies out in the other. Instead, it persists only at the nodes that are coupled to nodes in the other network through internetwork links. We speculate on the implications of these findings.


Asunto(s)
Modelos Teóricos , Probabilidad
14.
Med Vet Entomol ; 27(3): 332-8, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23336712

RESUMEN

Aedes polynesiensis Marks (Diptera: Culicidae) is the primary vector of lymphatic filariasis (LF) in the island countries and territories of the South Pacific. In the development of a novel control tool, the response of Ae. polynesiensis to six different colours (three solid fabrics, two patterned fabrics and a plastic tarp) was measured using a digital photographic system. Adult mosquitoes were placed into an environmental chamber and allowed to choose between a white target and one of six experimental targets. Mosquito landing frequency and landing duration were calculated. Adult female Ae. polynesiensis preferred all of the experimental targets to the white control target. Mosquito landing frequency was highest for the solid targets (black, navy blue and red) followed in turn by the two colour pattern targets and the polyethylene target. Mosquito landing duration was greater for experimental targets when compared with white control targets. Mosquito landing frequencies did not change over time during the course of the assay. The response of male Ae. polynesiensis was also measured when exposed to a 100% cotton black target. Male mosquitoes preferred the black target to the white control target, although at levels lower than that observed in female mosquitoes. The results suggest that future investigations evaluating the visual responses of Ae. polynesiensis mosquitoes are warranted, with a special emphasis on semi-field and field-based experiments.


Asunto(s)
Aedes/fisiología , Vuelo Animal , Insectos Vectores/fisiología , Control de Mosquitos/métodos , Animales , Color , Femenino , Masculino , Estimulación Luminosa , Fotograbar , Caracteres Sexuales , Percepción Visual
15.
Bull Entomol Res ; 103(3): 251-60, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23113940

RESUMEN

Insect cell lines provide useful in vitro models for studying biological systems, including interactions between mosquitoes and obligate intracellular endosymbionts such as Wolbachia pipientis. The Aedes albopictus Aa23 cell line was the first cell line developed to allow examination of Wolbachia infections. However, Wolbachia studies using Aa23 can be complicated by the presence of different cell types in the cell line and the substantial temporal variation in infection level. Two approaches were examined to ameliorate infection variability. In the first approach, multiple Aa23 passaging regimes were tested for an effect on infection variability. Fluorescence in situ hybridization (FISH) staining was used to characterize Wolbachia infection level over time. The results demonstrate an impact of passaging method on Wolbachia infection level, with some methods resulting in loss of infection. None of the passaging methods succeeded in effectively mitigating infection level variation. In a second approach, the clonal C7-10 A. albopictus cell line was infected with Wolbachia from Aa23 cells and Drosophila simulans (Riverside), resulting in cell lines designated C7-10B and C7-10R, respectively. Characterization via FISH staining showed greater stability and uniformity of Wolbachia infection in C7-10R relative to the infection in C7-10B. Characterization of the Aa23, C7-10B and C7-10R lines is discussed as a tool for the study of Wolbachia-host cell interactions.


Asunto(s)
Aedes/citología , Aedes/microbiología , Drosophila/microbiología , Wolbachia/crecimiento & desarrollo , Wolbachia/genética , Animales , Proteínas Bacterianas/genética , Técnicas de Cultivo de Célula/métodos , Línea Celular , Cartilla de ADN/genética , Hibridación Fluorescente in Situ , Indoles , Reacción en Cadena de la Polimerasa
16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(6 Pt 2): 066120, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23368017

RESUMEN

Most real-world networks do not live in isolation but are often coupled together within a larger system. Recent studies have shown that intersimilarity between coupled networks increases the connectivity of the overall system. However, unlike connected nodes in a single network, coupled nodes often share resources, like time, energy, and memory, which can impede flow processes through contention when intersimilarly coupled. We study a model of a constrained susceptible-infected-recovered (SIR) process on a system consisting of two random networks sharing the same set of nodes, where nodes are limited to interact with (and therefore infect) a maximum number of neighbors at each epidemic time step. We obtain that, in agreement with previous studies, when no limit exists (regular SIR model), positively correlated (intersimilar) coupling results in a lower epidemic threshold than negatively correlated (interdissimilar) coupling. However, in the case of the constrained SIR model, the obtained epidemic threshold is lower with negatively correlated coupling. The latter finding differentiates our work from previous studies and provides another step towards revealing the qualitative differences between single and coupled networks.


Asunto(s)
Biofisica/métodos , Enfermedades Transmisibles/epidemiología , Epidemias , Algoritmos , Conducta , Recursos en Salud , Humanos , Apoyo Social , Teoría de Sistemas
17.
J Med Entomol ; 48(5): 1008-15, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21936319

RESUMEN

The endosymbiotic bacteria Wolbachia manipulate host reproduction by inducing a form of sterility known as cytoplasmic incompatibility (CI), promoting the invasion of infection into natural host populations. CI has received attention for use in applied strategies to control insect vectors of disease. Thus, to understand both naturally occurring Wolbachia invasions and evaluate potential applied strategies, it is important to understand Wolbachia interactions with its host, including impacts on fitness and the CI level. In this study, we examined for an effect of Wolbachia on survivorship, developmental time, sex ratio, longevity, fecundity, and egg hatch of Aedes polynesiensis Marks, which is the primary vector of Wuchereria bancrofti in the South Pacific. In this study, we have compared strains of A. polynesiensis that are naturally and artificially infected with Wolbachia and additional strains that are aposymbiotic (Wolbachia removed to generate an uninfected strain). Artificially infected strains were observed to have increased larval mortality and decreased adult longevity when compared with aposymbiotic strains. Naturally infected strains were observed to have decreased larval mortality, pupal mortality, increased adult longevity, and a larger adult size when compared with aposymbiotic strains. Artificially infected males that were 4 wk old were able to induce high rates of CI, similar to young males. We discuss the results in relation to the natural spread of Wolbachia and Wolbachia-based applied strategies to modify A. polynesiensis populations.


Asunto(s)
Aedes/microbiología , Aedes/fisiología , Control Biológico de Vectores , Wolbachia/fisiología , Aedes/crecimiento & desarrollo , Envejecimiento , Animales , Citoplasma/microbiología , Femenino , Fertilidad , Aptitud Genética , Interacciones Huésped-Patógeno , Larva/crecimiento & desarrollo , Larva/microbiología , Larva/fisiología , Longevidad , Masculino , Reacción en Cadena de la Polimerasa , Dinámica Poblacional , Razón de Masculinidad , Simbiosis
18.
Lett Appl Microbiol ; 52(2): 168-76, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21214605

RESUMEN

AIMS: The Aedes albopictus C7-10 cell line was infected with Wolbachia strains wRi and wAlbB to create C7-10R and C7-10B cell lines, respectively. We compared two different methods, fluorescence in situ hybridization staining and SYTO11 staining, to describe these new Wolbachia infections in C7-10. METHODS AND RESULTS: Both staining methods were as efficient to stain Wolbachia. A formula was developed to quantify Wolbachia infection. The infection levels in C7-10B and C7-10R differed. The live stain SYTO11 was found to be useful to visualize Wolbachia in replicating host cells. Its potential cytotoxic effect at high concentration was investigated. CONCLUSIONS: C7-10 supported two Wolbachia infections, constituting new tools to study Wolbachia-host interactions. The different infection levels suggest that wRi and wAlbB have different requirements for their survival in C7-10 host cell line. Observation of SYTO11-stained live cells gave new insights on Wolbachia segregation pattern during host cell mitosis. SIGNIFICANCE AND IMPACT OF THE STUDY: Wolbachia-induced phenotypes in their arthropod and worm hosts could potentially be used to control pest populations. However, the mechanisms underlying these phenotypes are difficult to study because of Wolbachia's intracellular lifestyle. The Wolbachia infections in C7-10 described here could be used as in vitro models to investigate Wolbachia biology.


Asunto(s)
Colorantes Fluorescentes , Hibridación Fluorescente in Situ , Wolbachia/aislamiento & purificación , Aedes/citología , Animales , Línea Celular , Colorantes Fluorescentes/toxicidad
19.
Anaesthesia ; 65(2): 178-83, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20402845

RESUMEN

Different topical local anaesthetics have varying effects on skin blood flow and vascular reactivity. We compared the vasoactive properties of Rapydan, a new topical local anaesthetic, with those of Ametop and EMLA creams in 20 healthy volunteers. Blood flow and vascular reactivity in the forearm skin were assessed by laser Doppler flowmetry and the transient hyperaemic response ratio respectively, before and after the application of EMLA (for 60 min), Ametop (for 30 and 60 min) and Rapydan (for 30 min). Application of EMLA had no effect on skin blood flow (median (IQR [range]) change from baseline -0.9% (-63 to 414 [-38.5 to 51.3] %, p = 1.0)) or mean (SD) transient hyperaemic response ratio (from 2.86 (0.86) to 3.17 (1.3), p = 0.38). The application of Ametop for 60 min produced a greater median (IQR [range]) increase in blood flow from baseline (508 (-55 to 998 [148-649]) %) than Rapydan applied for 30 min 160 (-77 to 997 [45-301]) %, p = 0.001), and a similar decrease in mean (SD) transient hyperaemic response ratio (from 2.69 (1.16) to 1.08 (0.26) and from 2.83 (0.84) to 1.49 (0.93) respectively, p = 0.57).


Asunto(s)
Anestésicos Locales/administración & dosificación , Sistemas de Liberación de Medicamentos , Antebrazo/irrigación sanguínea , Piel/irrigación sanguínea , Administración Cutánea , Adulto , Anestesia Local/métodos , Anestésicos Combinados/administración & dosificación , Anestésicos Combinados/farmacología , Anestésicos Locales/farmacología , Vendajes , Humanos , Hiperemia/inducido químicamente , Hiperemia/fisiopatología , Flujometría por Láser-Doppler/métodos , Lidocaína/administración & dosificación , Lidocaína/farmacología , Combinación Lidocaína y Prilocaína , Masculino , Prilocaína/administración & dosificación , Prilocaína/farmacología , Flujo Sanguíneo Regional/efectos de los fármacos , Tetracaína/administración & dosificación , Tetracaína/farmacología , Adulto Joven
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