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1.
J Physiol ; 601(7): 1225-1246, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36930567

RESUMEN

Although hyperpolarization-activated cation (HCN) ion channels are well established to underlie cardiac pacemaker activity, their role in smooth muscle organs remains controversial. HCN-expressing cells are localized to renal pelvic smooth muscle (RPSM) pacemaker tissues of the murine upper urinary tract and HCN channel conductance is required for peristalsis. To date, however, the Ih pacemaker current conducted by HCN channels has never been detected in these cells, raising questions on the identity of RPSM pacemakers. Indeed, the RPSM pacemaker mechanisms of the unique multicalyceal upper urinary tract exhibited by humans remains unknown. Here, we developed immunopanning purification protocols and demonstrate that 96% of isolated HCN+ cells exhibit Ih . Single-molecule STORM to whole-tissue imaging showed HCN+ cells express single HCN channels on their plasma membrane and integrate into the muscular syncytium. By contrast, PDGFR-α+ cells exhibiting the morphology of ICC gut pacemakers were shown to be vascular mural cells. Translational studies in the homologous human and porcine multicalyceal upper urinary tracts showed that contractions and pacemaker depolarizations originate in proximal calyceal RPSM. Critically, HCN+ cells were shown to integrate into calyceal RPSM pacemaker tissues, and HCN channel block abolished electrical pacemaker activity and peristalsis of the multicalyceal upper urinary tract. Cumulatively, these studies demonstrate that HCN ion channels play a broad, evolutionarily conserved pacemaker role in both cardiac and smooth muscle organs and have implications for channelopathies as putative aetiologies of smooth muscle disorders. KEY POINTS: Pacemakers trigger contractions of involuntary muscles. Hyperpolarization-activated cation (HCN) ion channels underpin cardiac pacemaker activity, but their role in smooth muscle organs remains controversial. Renal pelvic smooth muscle (RPSM) pacemakers trigger contractions that propel waste away from the kidney. HCN+ cells localize to murine RPSM pacemaker tissue and HCN channel conductance is required for peristalsis. The HCN (Ih ) current has never been detected in RPSM cells, raising doubt whether HCN+ cells are bona fide pacemakers. Moreover, the pacemaker mechanisms of the unique multicalyceal RPSM of higher order mammals remains unknown. In total, 97% of purified HCN+ RPSM cells exhibit Ih . HCN+ cells integrate into the RPSM musculature, and pacemaker tissue peristalsis is dependent on HCN channels. Translational studies in human and swine demonstrate HCN channels are conserved in the multicalyceal RPSM and that HCN channels underlie pacemaker activity that drives peristalsis. These studies provide insight into putative channelopathies that can underlie smooth muscle dysfunction.


Asunto(s)
Canalopatías , Humanos , Ratones , Animales , Porcinos , Canalopatías/metabolismo , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/metabolismo , Riñón/metabolismo , Músculo Liso/fisiología , Cationes/metabolismo , Canales Catiónicos Regulados por Nucleótidos Cíclicos/metabolismo , Mamíferos/metabolismo
2.
BMC Genomics ; 24(1): 167, 2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37016278

RESUMEN

BACKGROUND: The processes of fertilization and egg activation are vital for early embryogenesis. However, while the mechanisms associated with key events during these processes differ among species and modes of spawning, the signal pathways underlying these processes are opaque for many fishes, including economically important species. RESULTS: We investigated phenotypic traits, ultrastructure and protein expression levels in the eggs of the topmouth culter (Culter alburnus), a protected and economically important freshwater fish that exhibits two spawning modes, producing semi-buoyant eggs and adhesive eggs. Unfertilized eggs of C. alburnus were examined, as well as eggs at fertilization and 30 min post fertilization. Our results showed that in semi-buoyant eggs, energy metabolism was activated at fertilization, followed by elevated protein expression of cytoskeleton and extracellular matrix (ECM)-receptor interactions that resulted in rapid egg swelling; a recognized adaptation for lotic habitats. In contrast, in adhesive eggs fertilization initiated the process of sperm-egg fusion and blocking of polyspermy, followed by enhanced protein expression of lipid metabolism and the formation of egg envelope adhesion and hardening, which are adaptive in lentic habitats. CONCLUSION: Our findings indicate that alternative signal pathways differ between modes of spawning and timing during the key processes of fertilization and egg activation, providing new insights into the molecular mechanisms involved in adaptive early embryonic development in teleost fishes.


Asunto(s)
Fertilización , Semen , Animales , Masculino , Espermatozoides/fisiología , Peces , Transducción de Señal , Óvulo
3.
J Clin Immunol ; 43(1): 136-150, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36050429

RESUMEN

PURPOSE: The aim of this study was to characterize clinical effects and biomarkers in three patients with chronic mucocutaneous candidiasis (CMC) caused by gain-of-function (GOF) mutations in the STAT1 gene during treatment with Janus kinase (JAK) inhibitors. METHODS: Mass cytometry (CyTOF) was used to characterize mononuclear leukocyte populations and Olink assay to quantify 265 plasma proteins. Flow-cytometric Assay for Specific Cell-mediated Immune-response in Activated whole blood (FASCIA) was used to quantify the reactivity against Candida albicans. RESULTS: Overall, JAK inhibitors improved clinical symptoms of CMC, but caused side effects in two patients. Absolute numbers of neutrophils, T cells, B cells, and NK cells were sustained during baricitinib treatment. Detailed analysis of cellular subsets, using CyTOF, revealed increased expression of CD45, CD52, and CD99 in NK cells, reflecting a more functional phenotype. Conversely, monocytes and eosinophils downregulated CD16, consistent with reduced inflammation. Moreover, T and B cells showed increased expression of activation markers during treatment. In one patient with a remarkable clinical effect of baricitinib treatment, the immune response to C. albicans increased after 7 weeks of treatment. Alterations in plasma biomarkers involved downregulation of cellular markers CXCL10, annexin A1, granzyme B, granzyme H, and oncostatin M, whereas FGF21 was the only upregulated marker after 7 weeks. After 3 months, IFN-É£ and CXCL10 were downregulated. CONCLUSIONS: The clinical effect of JAK inhibitor treatment of CMC is promising. Several biological variables were altered during baricitinib treatment demonstrating that lymphocytes, NK cells, monocytes, and eosinophils were affected. In parallel, cellular reactivity against C. albicans was enhanced.


Asunto(s)
Candidiasis Mucocutánea Crónica , Inhibidores de las Cinasas Janus , Humanos , Mutación con Ganancia de Función , Inhibidores de las Cinasas Janus/uso terapéutico , Candidiasis Mucocutánea Crónica/diagnóstico , Candidiasis Mucocutánea Crónica/tratamiento farmacológico , Candidiasis Mucocutánea Crónica/genética , Biomarcadores , Factor de Transcripción STAT1/metabolismo
4.
Health Expect ; 26(3): 1236-1245, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36864604

RESUMEN

INTRODUCTION: Clinical trials must include diverse participants to ensure the wide applicability of results. However, people from ethnic minorities are included in clinical trials at rates lower than expected given their share of the population. Working with South Riverside Community Development Centre (SRCDC), Talking Trials used public engagement to foster discussions around the underrepresentation of those from minority ethnic communities in clinical trials and to identify and address concerns surrounding trial participation. METHODS: We conducted three workshops with 13 co-researchers from minority ethnic backgrounds. We explored perceptions and understanding of clinical trials alongside participatory art activities to help move away from verbocentric methods of communication. These artworks formed an exhibition that was presented to the community, prompting further discussions and engagement. FINDINGS: Co-production workshops were an effective tool to introduce the public to trial research. With little knowledge of clinical trials at the beginning of the process, our co-researchers formed a cohesive group, sharing initial fears and mistrust towards trials. As conversations progressed these attitudes clearly shifted. Artwork produced during the workshops was incorporated into an exhibition. Quotes and creative pieces from the group were included to reflect the themes identified. Presenting the exhibition at Riverside Festival enabled further engagement with a wider diverse community. The focus on co-production helped build a network of individuals new to research and keen to become involved further. CONCLUSION: Inclusive and democratic co-production, enriched by participatory art practices, provided a powerful means of enabling our group to create new insights and foster new relationships. Projects like Talking Trials can diversify the research process itself-for example, four co-researchers have commenced lay research partner roles on trial management groups and a lay advisory group is in development. PATIENT OR PUBLIC CONTRIBUTION: Three members of staff at SRCDC were on the project delivery group and involved in the initial project design, subsequently helping to connect us with members of the Riverside community to work as co-researchers. Two of the SRCDC staff are co-authors of this manuscript. The project had 13 public co-researchers guiding the direction of this research and creating the artwork displayed in the art exhibition.


Asunto(s)
Etnicidad , Grupos Minoritarios , Humanos , Actitud
5.
Scand J Immunol ; 95(4): e13153, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35244285

RESUMEN

Infections with SARS-CoV-2 have been unduly severe in patients with haematological malignancies, in particular in those with chronic lymphocytic leukaemia (CLL). Based on a series of observations, we propose that an underlying mechanism for the aggressive clinical course of COVID-19 in CLL is a paucity of plasmacytoid dendritic cells (pDCs) in these patients. Indeed, pDCs express Toll-like receptor 7 (TLR7), which together with interferon-regulatory factor 7 (IRF7), enables pDCs to produce large amounts of type I interferons, essential for combating COVID-19. Treatment of CLL with Bruton's tyrosine kinase (BTK) inhibitors increased the number of pDCs, likely secondarily to the reduction in the tumour burden.


Asunto(s)
COVID-19 , Leucemia Linfocítica Crónica de Células B , COVID-19/complicaciones , Células Dendríticas , Humanos , Factor 7 Regulador del Interferón , Leucemia Linfocítica Crónica de Células B/complicaciones , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , SARS-CoV-2 , Receptor Toll-Like 7
6.
J Nutr ; 152(6): 1560-1573, 2022 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-35285906

RESUMEN

BACKGROUND: Physiologic and psychologic stress slow healing from experimental wounds by impairing immune function. OBJECTIVES: We aimed to determine whether supplemental protein and multinutrient supplementation improved wound healing markers after acute stress induced by acute sleep restriction. METHODS: In this single-blind, crossover study in generally healthy young adults (18 males/2 females; mean ± SD age: 19.7 ± 2.30 y), experimental wounds were created by removing the top layer of forearm blisters induced via suction after 48 h of 72-h sleep restriction (2-h nightly sleep), a protocol previously shown to delay wound healing. Skin barrier restoration (measured by transepidermal water loss) assessed wound healing ≤10 d postblistering, and local immune responses were evaluated by serial measurement of cytokine concentrations in fluid collected at wound sites for 48 h postblistering. Participants consumed controlled, isocaloric diets with either 0.900 g · kg-1 · d-1 protein plus placebo (PLA) or 1.50 g · kg-1 · d-1 protein plus multinutrient beverage [l-arginine: 20.0 g/d; l-glutamine: 30.0 g/d; omega-3 (n-3) fatty acids: 1.00 g/d; zinc sulfate: 24.0 mg/d; cholecalciferol: 800 IU/d; and vitamin C: 400 mg/d] (NUT) during sleep restriction and for 4 d afterwards. RESULTS: Skin barrier restoration (primary outcome) was shorter for NUT (median: 3.98 d; IQR: 1.17 d) than for PLA (median: 5.25 d; IQR: 1.05 d) (P = 0.001). Cytokines from wound fluid (secondary outcome) increased over time (main effect of time P ≤ 0.001), except IL-13 (P = 0.07); however, no effects of treatment were observed. CONCLUSIONS: Supplemental nutrition may promote wound healing after sleep restriction in healthy adults including military personnel, the latter of which also have a high incidence of wounds and infection.This trial was registered at clinicaltrials.gov as NCT03525184.


Asunto(s)
Ácidos Grasos Omega-3 , Cicatrización de Heridas , Adolescente , Adulto , Bebidas , Estudios Cruzados , Citocinas , Femenino , Humanos , Masculino , Poliésteres/farmacología , Método Simple Ciego , Sueño , Adulto Joven
7.
J Fish Biol ; 101(6): 1501-1508, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36134556

RESUMEN

Much of the biological diversity we see today is thought to be the product of evolutionary radiation, the rapid proliferation of species from a single ancestor into multiple discrete forms. Spatial heterogeneity in environmental variables has been proposed as creating the necessary ecological opportunity to stimulate evolutionary radiation. Nonetheless, the ecological mechanisms generating and maintaining diversity in spatially heterogeneous environments are not fully understood. The authors investigated the role of strong spatial heterogeneity in generating ecological opportunity in an evolutionary radiation of freshwater populations of the three-spined stickleback (Gasterosteus aculeatus L.) on the island of North Uist using a spatially explicit Bayesian model. The authors identified pH, loch surface area and body size as predictors of variance in the number of lateral plates that comprise anti-predator armour in G. aculeatus. An East-West gradient of pH, a product of the distinctive environment of North Uist, generates a robust selective environment facilitating G. aculeatus evolutionary radiation. Larger lochs were associated with atypical phenotypes, possibly related to larger population sizes and greater selection efficiency. An association between pH and lateral plate number is likely an effect of body size, with a positive relationship between body size and lateral plate number that is mediated by swimming efficiency in G. aculeatus.


Asunto(s)
Evolución Biológica , Smegmamorpha , Animales , Teorema de Bayes , Smegmamorpha/genética , Tamaño Corporal , Concentración de Iones de Hidrógeno
8.
J Fish Biol ; 99(5): 1677-1695, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34498257

RESUMEN

The Kanehira bitterling, Acheilognathus rhombeus, is a freshwater fish, discontinuously distributed in western Japan and the Korean Peninsula. Unusually among bitterling it is an autumn-spawning species and shows developmental diapause. Consequently, the characterization of its evolutionary history is significant not only in the context of the fish assemblage of East Asia, but also for understanding life-history evolution. This study aimed to investigate the phylogeography of A. rhombeus and its sister species Acheilognathus barbatulus, distributed in China, using a mitochondrial analysis of the ND1 gene from 311 samples collected from 50 localities in Japan and continental Asia. Phylogenetic analysis revealed that A. barbatulus is included in A. rhombeus and genetically closer to Japanese A. rhombeus than to Korean A. rhombeus. Divergence of Korean A. rhombeus and A. barbatulus from Japanese A. rhombeus was estimated to be from the late Pliocene (3.44 Mya) and the early Pleistocene (1.98 Mya), respectively. Each event closely coincided with the time of the Japan Sea opening. Japanese A. rhombeus comprised seven lineages: three in Honshu and four in Kyushu. One lineage in central Kyushu was genetically closer to the Honshu lineages than to other lineages in northern Kyushu. Divergence of Japanese lineages was estimated to be from the early to middle Pleistocene (0.55-0.93 Mya), during a period of geological and paleoclimatic change, including volcanic activity. Population expansion in the late Pleistocene (<0.10 Ma) was suggested in many of the lineages, which accords with other freshwater fishes. Biogeographically the ancestral A. rhombeus/A. barbatulus was likely to have repeatedly colonized Japan from the continent through land bridges in the late Pliocene and the early Pleistocene. However, the close genetic relationship between Japanese A. rhombeus and A. barbatulus suggests another possibility, with the second colonization occurring in reverse, from Japan to China. The small genetic distance between them indicates that the colonization occurred later than colonization events of other freshwater fishes, including other bitterling species.


Asunto(s)
Cipriniformes , ADN Mitocondrial , Animales , ADN Mitocondrial/genética , Mitocondrias , Filogenia , Filogeografía
9.
Biochemistry ; 59(6): 736-741, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-32013401

RESUMEN

Hedgehog proteins, a family of vital cell signaling factors, are expressed in precursor form, which requires specialized autoprocessing, called cholesterolysis, for full biological activity. Cholesterolysis occurs in cis through the action of the precursor's C-terminal enzymatic domain, HhC. In this work, we describe HhC activator compounds (HACs), a novel class of noncovalent modulators that induce autoprocessing infidelity, diminishing native cholesterolysis in favor of precursor autoproteolysis, an otherwise minor and apparently nonphysiological side reaction. HAC-induced autoproteolysis generates hedgehog protein that is cholesterol free and hence signaling deficient. The most effective HAC has an AC50 of 9 µM, accelerates HhC autoproteolytic activity by 225-fold, and functions in the presence and absence of cholesterol, the native substrate. HACs join a rare class of "antagonists" that suppress native enzymatic activity by subverting mechanistic fidelity.


Asunto(s)
Colesterol/biosíntesis , Proteínas de Drosophila/biosíntesis , Proteínas Hedgehog/biosíntesis , Catálisis , Colesterol/genética , Proteínas de Drosophila/genética , Variación Genética/fisiología , Proteínas Hedgehog/genética , Proteolisis
10.
Mol Phylogenet Evol ; 133: 1-11, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30586649

RESUMEN

South-east Europe, along with the adjacent region of south-west Asia, is an important biodiversity hotspot with high local endemism largely contributed by contemporary continental lineages that retreated to southern refugia during colder Quaternary periods. We investigated the genetic diversity of the European bitterling fish (Rhodeus amarus) species complex (Cyprinidae) across its range in the western Palearctic, but with a particular emphasis in the region of Balkan, Pontic and Caspian refugia. We genotyped 12 polymorphic microsatellite loci and a partial sequence of mitochondrial gene cytochrome b (CYTB) for a set of 1,038 individuals from 60 populations. We used mtDNA sequences to infer phylogenetic relationships and historical demography, and microsatellite markers to describe fine-scale genetic variability and structure. Our mtDNA analysis revealed six well-supported lineages, with limited local co-occurrence. Two lineages are distributed throughout central and western Europe (lineages "A" and "B"), with two zones of secondary contact. Another two lineages were restricted to the Ponto-Aegean region of Greece (lineages "C" and "D") and the final two lineages were restricted south of the Caucasus mountains (lineage "E" from the Black Sea watershed and lineage "F" from the Caspian watershed). A signal of recent expansion was revealed in the two widespread lineages and the Ponto-Aegean lineage "C". The geographic distribution of clusters detected by nuclear microsatellites corresponded well with mitochondrial lineages and demonstrated finely sub-structured populations. A profound population structure suggested a significant role of genetic drift in differentiation among lineages. Lineage divergence in the Ponto-Aegean and Caspian regions are substantial, supporting the validity of two described endemic species (Rhodeus meridionalis as lineage "D" and Rhodeus colchicus as lineage "E") and invite taxonomic evaluation of the other two southern lineages (Thracean "C" and Caspian "F").


Asunto(s)
Cyprinidae/clasificación , Animales , Asia Occidental , Biodiversidad , Cyprinidae/genética , Citocromos b/genética , ADN Mitocondrial/química , Demografía , Europa (Continente) , Flujo Genético , Variación Genética , Genotipo , Repeticiones de Microsatélite , Mitocondrias/genética , Filogenia
11.
J Sleep Res ; 28(3): e12637, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-29171171

RESUMEN

Sleep restriction degrades cognitive and motor performance, which can adversely impact job performance and increase the risk of accidents. Military personnel are prone to operating under sleep restriction, and previous work suggests that military marksmanship may be negatively affected under such conditions. Results of these studies, however, are mixed and have often incorporated additional stressors (e.g. energy restriction) beyond sleep restriction. Moreover, few studies have investigated how the degree of difficulty of a marksmanship task impacts performance following sleep restriction. The purpose of the current experiment was to study the effects of sleep restriction on marksmanship while minimizing the potential influence of other forms of stress. A friend-foe discrimination challenge with greater or lesser degrees of complexity (high versus low load) was used as the primary marksmanship task. Active duty Soldiers were recruited, and allowed 2 h of sleep every 24 h over a 72-h testing period. Marksmanship tasks, cognitive assessment metrics and the NASA-Task Load Index were administered daily. Results indicated that reaction times to shoot foe targets and signal friendly targets slowed over time. In addition, the ability to correctly discriminate between friend and foe targets significantly decreased in the high-cognitive-load condition over time despite shot accuracy remaining stable. The NASA-Task Load Index revealed that, although marksmanship performance degraded, participants believed their performance did not change over time. These results further characterize the consequences of sleep restriction on marksmanship performance and the perception of performance, and reinforce the importance of adequate sleep among service members when feasible.


Asunto(s)
Cognición/fisiología , Tiempo de Reacción/fisiología , Privación de Sueño/psicología , Análisis y Desempeño de Tareas , Adulto , Toma de Decisiones , Humanos , Masculino , Personal Militar
12.
J Infect Dis ; 218(12): 1861-1875, 2018 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-29986030

RESUMEN

Background: In this study, we aimed to identify the effect of market-level risk factors on avian influenza (AI) infection in poultry and humans and generate evidence that will inform AI prevention and control programs at live bird markets (LBMs). Methods: We performed a systematic literature review in both English and Chinese search engines. We estimated the pooled odds ratios of biosecurity indicators relating to AI infections at market level using a quality effects (QE) meta-analysis model. Results: Biosecurity measures effective at reducing AI market contamination and poultry infection at LBMs include smaller market size, selling single poultry species and separating different species, performing cleaning and disinfection and market closures, ban on overnight storage, and sourcing poultry from local areas. Our meta-analysis indicates that higher risk of exposure to AI infection occurs in workers at retail LBMs, female workers, and those who contact ducks, conduct cleaning, slaughtering, defeathering, or evisceration. Conclusions: The most effective strategies to reduce AI market contamination identified in this study should target larger LBMs that are located at noncentral city areas and sell and slaughter multispecies of live poultry. Live bird market workers directly involved in cleaning and poultry processing tasks should participate in occupational health and safety programs.


Asunto(s)
Virus de la Influenza A , Gripe Aviar/prevención & control , Gripe Humana/prevención & control , Aves de Corral/virología , Animales , Comercio , Inocuidad de los Alimentos , Humanos , Gripe Aviar/virología , Gripe Humana/virología
13.
J Evol Biol ; 31(11): 1610-1622, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30066434

RESUMEN

In many taxa, odour cues mediate mating decisions. A key question is what these odours comprise, where they are produced, and what they signal. Using rose bitterling, fish that spawn in the gills of freshwater mussels, we investigated the role of sperm cues on female oviposition decisions using individuals of known MHC genotype. Male bitterling frequently released sperm prior to female oviposition and females responded with an increased probability of oviposition and released a greater number of eggs, particularly if males had a dissimilar MHC genotype. These mating preferences by females were shown to be adaptive, with MHC dissimilarity of males and females correlated positively with embryo survival. These results support a role for indirect benefits to rose bitterling mate choice, and we propose that sperm acts as a releaser pheromone in bitterling, functioning as a sexual ornament signalling male quality as a mate.


Asunto(s)
Cipriniformes/genética , Cipriniformes/fisiología , Preferencia en el Apareamiento Animal , Espermatozoides/fisiología , Animales , Femenino , Regulación de la Expresión Génica , Complejo Mayor de Histocompatibilidad/genética , Masculino
14.
BMC Public Health ; 18(1): 402, 2018 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-29587701

RESUMEN

BACKGROUND: Policy and decision-making processes are routinely challenged by the complex and dynamic nature of environmental health problems. System dynamics modelling has demonstrated considerable value across a number of different fields to help decision-makers understand and predict the dynamic behaviour of complex systems in support the development of effective policy actions. In this scoping review we investigate if, and in what contexts, system dynamics modelling is being used to inform policy or decision-making processes related to environmental health. METHODS: Four electronic databases and the grey literature were systematically searched to identify studies that intersect the areas environmental health, system dynamics modelling, and decision-making. Studies identified in the initial screening were further screened for their contextual, methodological and application-related relevancy. Studies deemed 'relevant' or 'highly relevant' according to all three criteria were included in this review. Key themes related to the rationale, impact and limitation of using system dynamics in the context of environmental health decision-making and policy were analysed. RESULTS: We identified a limited number of relevant studies (n = 15), two-thirds of which were conducted between 2011 and 2016. The majority of applications occurred in non-health related sectors (n = 9) including transportation, public utilities, water, housing, food, agriculture, and urban and regional planning. Applications were primarily targeted at micro-level (local, community or grassroots) decision-making processes (n = 9), with macro-level (national or international) decision-making to a lesser degree. There was significant heterogeneity in the stated rationales for using system dynamics and the intended impact of the system dynamics model on decision-making processes. A series of user-related, technical and application-related limitations and challenges were identified. None of the reported limitations or challenges appeared unique to the application of system dynamics within the context of environmental health problems, but rather to the use of system dynamics in general. CONCLUSIONS: This review reveals that while system dynamics modelling is increasingly being used to inform decision-making related to environmental health, applications are currently limited. Greater application of system dynamics within this context is needed before its benefits and limitations can be fully understood.


Asunto(s)
Técnicas de Apoyo para la Decisión , Salud Ambiental , Política de Salud , Humanos , Modelos Teóricos
15.
J Fish Biol ; 103(4): 749-751, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37807628

Asunto(s)
Peces , Animales
16.
Oecologia ; 183(2): 379-389, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27888335

RESUMEN

Generalist parasites have the capacity to infect multiple hosts. The temporal pattern of host specificity by generalist parasites is rarely studied, but is critical to understanding what variables underpin infection and thereby the impact of parasites on host species and the way they impose selection on hosts. Here, the temporal dynamics of infection of four species of freshwater mussel by European bitterling fish (Rhodeus amarus) was investigated over three spawning seasons. Bitterling lay their eggs in the gills of freshwater mussels, which suffer reduced growth, oxygen stress, gill damage and elevated mortality as a result of parasitism. The temporal pattern of infection of mussels by European bitterling in multiple populations was examined. Using a Bernoulli Generalized Additive Mixed Model with Bayesian inference it was demonstrated that one mussel species, Unio pictorum, was exploited over the entire bitterling spawning season. As the season progressed, bitterling showed a preference for other mussel species, which were inferior hosts. Temporal changes in host use reflected elevated density-dependent mortality in preferred hosts that were already infected. Plasticity in host specificity by bitterling conformed with the predictions of the host selection hypothesis. The relationship between bitterling and their host mussels differs qualitatively from that of avian brood parasites.


Asunto(s)
Especificidad del Huésped , Interacciones Huésped-Parásitos , Animales , Teorema de Bayes , Cyprinidae , Parásitos
17.
Epilepsy Behav ; 68: 22-30, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28109985

RESUMEN

Organophosphorus nerve agents (OPNAs) are irreversible inhibitors of acetylcholinesterase that pose a serious threat to public health because of their use as chemical weapons. Exposure to high doses of OPNAs can dramatically potentiate cholinergic synaptic activity and cause status epilepticus (SE). Current standard of care for OPNA exposure involves treatment with cholinergic antagonists, oxime cholinesterase reactivators, and benzodiazepines. However, data from pre-clinical models suggest that OPNA-induced SE rapidly becomes refractory to benzodiazepines. Neuroactive steroids (NAS), such as allopregnanolone, retain anticonvulsant activity in rodent models of benzodiazepine-resistant SE, perhaps because they modulate a broader variety of GABAA receptor subtypes. SGE-516 is a novel, next generation NAS and a potent and selective GABAA receptor positive allosteric modulator (PAM). The present study first established that SGE-516 reduced electrographic seizures in the rat lithium-pilocarpine model of pharmacoresistant SE. Then the anticonvulsant activity of SGE-516 was investigated in the soman-intoxication model of OPNA-induced SE. SGE-516 (5.6, 7.5, and 10mg/kg, IP) significantly reduced electrographic seizure activity compared to control when administered 20min after SE onset. When 10mg/kg SGE-516 was administered 40min after SE onset, seizure activity was still significantly reduced compared to control. In addition, all cohorts of rats treated with SGE-516 exhibited significantly reduced neuronal cell death as measured by FluoroJade B immunohistochemistry. These data suggest synthetic NASs that positively modulate both synaptic and extrasynaptic GABAA receptors may be candidates for further study in the treatment of OPNA-induced SE.


Asunto(s)
Anticonvulsivantes/farmacología , Muerte Celular/efectos de los fármacos , Moduladores del GABA/farmacología , Neuronas/efectos de los fármacos , Neurotransmisores/farmacología , Convulsiones/tratamiento farmacológico , Soman , Estado Epiléptico/tratamiento farmacológico , Animales , Anticonvulsivantes/uso terapéutico , Convulsivantes , Moduladores del GABA/uso terapéutico , Masculino , Neurotransmisores/uso terapéutico , Pilocarpina , Ratas , Ratas Sprague-Dawley , Convulsiones/inducido químicamente , Estado Epiléptico/inducido químicamente
18.
Mol Biol Evol ; 32(4): 888-95, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25534027

RESUMEN

Epigenetic marks such as DNA methylation play important biological roles in gene expression regulation and cellular differentiation during development. To examine whether DNA methylation patterns are potentially associated with naturally occurring phenotypic differences, we examined genome-wide DNA methylation within Gasterosteus aculeatus, using reduced representation bisulfite sequencing. First, we identified highly methylated regions of the stickleback genome, finding such regions to be located predominantly within genes, and associated with genes functioning in metabolism and biosynthetic processes, cell adhesion, signaling pathways, and blood vessel development. Next, we identified putative differentially methylated regions (DMRs) of the genome between complete and low lateral plate morphs of G. aculeatus. We detected 77 DMRs that were mainly located in intergenic regions. Annotations of genes associated with these DMRs revealed potential functions in a number of known divergent adaptive phenotypes between G. aculeatus ecotypes, including cardiovascular development, growth, and neuromuscular development.


Asunto(s)
Metilación de ADN , Genoma , Fenotipo , Smegmamorpha/genética , Animales , Secuencia de Bases , Adhesión Celular/genética , Femenino , Genes , Crecimiento y Desarrollo/genética , Redes y Vías Metabólicas/genética , Datos de Secuencia Molecular , Transducción de Señal/genética
19.
J Anat ; 228(5): 812-25, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26805464

RESUMEN

Renal pacemaker activity triggers peristaltic upper urinary tract contractions that propel waste from the kidney to the bladder, a process prone to congenital defects that are the leading cause of pediatric kidney failure. Recently, studies have discovered that hyperpolarization-activated cation (HCN) and T-type calcium (TTC) channel conductances underlie murine renal pacemaker activity, setting the origin and frequency and coordinating upper urinary tract peristalsis. Here, we determined whether this ion channel expression is conserved in the porcine and human urinary tracts, which share a distinct multicalyceal anatomy with multiple pacemaker sites. Double chromagenic immunohistochemistry revealed that HCN isoform 3 is highly expressed at the porcine minor calyces, the renal pacemaker tissues, whereas the kidney and urinary tract smooth muscle lacked this HCN expression. Immunofluorescent staining demonstrated that HCN(+) cells are integrated within the porcine calyx smooth muscle, and that they co-express TTC channel isoform Cav3.2. In humans, the anatomic structure of the minor calyx pacemaker was assayed via hematoxylin and eosin analyses, and enabled the visualization of the calyx smooth muscle surrounding adjacent papillae. Strikingly, immunofluorescence revealed that HCN3(+) /Cav3.2(+) cells are also localized to the human minor calyx smooth muscle. Collectively, these data have elucidated a conserved molecular signature of HCN and TTC channel expression in porcine and human calyx pacemaker tissues. These findings provide evidence for the mechanisms that can drive renal pacemaker activity in the multi-calyceal urinary tract, and potential causes of obstructive uropathies.


Asunto(s)
Canales de Calcio Tipo T/biosíntesis , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/biosíntesis , Riñón/fisiología , Animales , Relojes Biológicos/fisiología , Técnica del Anticuerpo Fluorescente , Humanos , Inmunohistoquímica , Peristaltismo/fisiología , Porcinos
20.
Proc Biol Sci ; 282(1809): 20151046, 2015 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-26041347

RESUMEN

The ability to attract mates, acquire resources for reproduction, and successfully outcompete rivals for fertilizations may make demands on cognitive traits--the mechanisms by which an animal acquires, processes, stores and acts upon information from its environment. Consequently, cognitive traits potentially undergo sexual selection in some mating systems. We investigated the role of cognitive traits on the reproductive performance of male rose bitterling (Rhodeus ocellatus), a freshwater fish with a complex mating system and alternative mating tactics. We quantified the learning accuracy of males and females in a spatial learning task and scored them for learning accuracy. Males were subsequently allowed to play the roles of a guarder and a sneaker in competitive mating trials, with reproductive success measured using paternity analysis. We detected a significant interaction between male mating role and learning accuracy on reproductive success, with the best-performing males in maze trials showing greater reproductive success in a sneaker role than as a guarder. Using a cross-classified breeding design, learning accuracy was demonstrated to be heritable, with significant additive maternal and paternal effects. Our results imply that male cognitive traits may undergo intra-sexual selection.


Asunto(s)
Cognición , Cyprinidae/fisiología , Carácter Cuantitativo Heredable , Conducta Sexual Animal , Aprendizaje Espacial , Animales , Cyprinidae/genética , Femenino , Masculino , Reproducción
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