Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 140
Filtrar
1.
J Environ Qual ; 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38853346

RESUMEN

Quantifying nitrate leaching in agricultural fields is often complicated by inability to capture all water draining through a specific area. We designed and tested undisturbed soil monoliths (termed "soil block mesocosms") to achieve complete collection of drainage. Each mesocosm measures 1.5 m × 1.5 m × 1.2 m and is enclosed by steel on the sides and bottom with a single outlet to collect drainage. We compared measurements from replicate mesocosms planted to corn (Zea mays L.) with a nearby field experiment with tile-drained plots ("drainage plots"), and with drainage from nearby watersheds from 2020 through 2022 under drought conditions. Annual mesocosm drainage volumes were 6.5-24.6 cm greater than from the drainage plots, likely because the mesocosms were isolated from the subsoil and could not store groundwater below the drain depth, whereas the drainage plots accumulated infiltration as groundwater. Thus, we obtained consistent nitrate leaching measurements from the mesocosms even when some drainage plots yielded no water. Despite drainage volume differences, mean flow-weighted nitrate concentrations were similar between mesocosms and drainage plots in 2 of 3 years. Mesocosm annual drainage volume was 8.7 cm lower to 16.7 cm higher than watershed drainage, likely due to lagged influences of groundwater. Corn yields were lower in mesocosms than drainage plots in 2020, but with irrigation, yields were similar in subsequent years. Mean 2020 surface soil moisture and temperature were similar between the mesocosms and nearby fields. Based on these comparisons, the mesocosms provide a robust method to measure nitrate leaching with lower variability than field plots.

2.
Am J Obstet Gynecol ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38697337

RESUMEN

BACKGROUND: The Multi-Omics for Mothers and Infants consortium aims to improve birth outcomes. Preterm birth is a major obstetrical complication globally and causes significant infant and childhood morbidity and mortality. OBJECTIVE: We analyzed placental samples (basal plate, placenta or chorionic villi, and the chorionic plate) collected by the 5 Multi-Omics for Mothers and Infants sites, namely The Alliance for Maternal and Newborn Health Improvement Bangladesh, The Alliance for Maternal and Newborn Health Improvement Pakistan, The Alliance for Maternal and Newborn Health Improvement Tanzania, The Global Alliance to Prevent Prematurity and Stillbirth Bangladesh, and The Global Alliance to Prevent Prematurity and Stillbirth Zambia. The goal was to analyze the morphology and gene expression of samples collected from preterm and uncomplicated term births. STUDY DESIGN: The teams provided biopsies from 166 singleton preterm (<37 weeks' gestation) and 175 term (≥37 weeks' gestation) deliveries. The samples were fixed in formalin and paraffin embedded. Tissue sections from these samples were stained with hematoxylin and eosin and subjected to morphologic analyses. Other placental biopsies (n=35 preterm, 21 term) were flash frozen, which enabled RNA purification for bulk transcriptomics. RESULTS: The morphologic analyses revealed a surprisingly high rate of inflammation that involved the basal plate, placenta or chorionic villi, and the chorionic plate. The rate of inflammation in chorionic villus samples, likely attributable to chronic villitis, ranged from 25% (Pakistan site) to 60% (Zambia site) of cases. Leukocyte infiltration in this location vs in the basal plate or chorionic plate correlated with preterm birth. Our transcriptomic analyses identified 267 genes that were differentially expressed between placentas from preterm vs those from term births (123 upregulated, 144 downregulated). Mapping the differentially expressed genes onto single-cell RNA sequencing data from human placentas suggested that all the component cell types, either singly or in subsets, contributed to the observed dysregulation. Consistent with the histopathologic findings, gene ontology analyses highlighted the presence of leukocyte infiltration or activation and inflammatory responses in both the fetal and maternal compartments. CONCLUSION: The relationship between placental inflammation and preterm birth is appreciated in developed countries. In this study, we showed that this link also exists in developing geographies. In addition, among the participating sites, we found geographic- and population-based differences in placental inflammation and preterm birth, suggesting the importance of local factors.

3.
Proc Natl Acad Sci U S A ; 121(19): e2315597121, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38687786

RESUMEN

Snakebite envenoming is a neglected tropical disease that causes substantial mortality and morbidity globally. The venom of African spitting cobras often causes permanent injury via tissue-destructive dermonecrosis at the bite site, which is ineffectively treated by current antivenoms. To address this therapeutic gap, we identified the etiological venom toxins in Naja nigricollis venom responsible for causing local dermonecrosis. While cytotoxic three-finger toxins were primarily responsible for causing spitting cobra cytotoxicity in cultured keratinocytes, their potentiation by phospholipases A2 toxins was essential to cause dermonecrosis in vivo. This evidence of probable toxin synergism suggests that a single toxin-family inhibiting drug could prevent local envenoming. We show that local injection with the repurposed phospholipase A2-inhibiting drug varespladib significantly prevents local tissue damage caused by several spitting cobra venoms in murine models of envenoming. Our findings therefore provide a therapeutic strategy that may effectively prevent life-changing morbidity caused by snakebite in rural Africa.


Asunto(s)
Acetatos , Venenos Elapídicos , Indoles , Cetoácidos , Necrosis , Mordeduras de Serpientes , Animales , Mordeduras de Serpientes/tratamiento farmacológico , Ratones , Humanos , Acrilamidas/farmacología , Fosfolipasas A2/metabolismo , Naja , Elapidae , Queratinocitos/efectos de los fármacos , Piel/efectos de los fármacos , Piel/patología , Reposicionamiento de Medicamentos
5.
Res Sq ; 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38464284

RESUMEN

Background: Fluoride exposure during pregnancy has been associated with various effects on offspring, including changes in behavior and IQ. To provide clues to possible mechanisms by which fluoride affects human fetal development, we completed proteomic analyses of cord blood serum collected from second-trimester pregnant women residing in Northern California with either high or low fluoride exposure, as identified by maternal serum fluoride concentrations. Objective: To identify changes in cord blood proteins associated with maternal serum fluoride concentration in pregnant women living in Northern California. Methods: The proteomes of 19 archived second-trimester cord blood samples representing highest and lowest serum fluoride concentrations from a cohort of 48 women living in Northern California, previously analyzed for serum, urine and amniotic fluoride concentrations, were characterized by mass spectrometry. Proteins highly correlated to maternal serum fluoride concentrations were identified, and further compared in a group of samples from women with the highest serum fluoride to the group with the lowest maternal serum fluoride concentrations. Results: Nine cord blood proteins were significantly correlated with maternal serum fluoride concentrations. Six of these proteins, including apolipoprotein B-100, delta homolog 1, coagulation factor X, mimecan, plasma kallikrein, and vasorin, were significantly decreased in the cord blood from women with the highest serum fluoride levels. Conclusion: Changes in the relative amounts of second trimester cord blood proteins included proteins associated with the development of the fetal hematopoetic system.

6.
IBRO Neurosci Rep ; 16: 249-259, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38370006

RESUMEN

All of the brain structures and white matter that make up Papez' circuit, as well as the circuit as a whole, are implicated in the literature in episodic memory formation and recall. This paper shows that Papez' circuit has the detailed structure and connectivity that is evidently required to support the episodic memory engram, and that identifying Papez' circuit as the location of the engram answers a number of long-standing questions regarding the role of medial temporal lobe structures in episodic memory. The paper then shows that the process by which the episodic memory engram may be formed is a network-wide Hebbian potentiation termed "racetrack potentiation", whose frequency corresponds to that observed in vivo in humans for memory functions. Further, by considering the microcircuits observed in the medial temporal lobe structures forming Papez' circuit, the paper establishes the neural mechanisms behind the required functions of sensory information storage and recall, pattern completion, pattern separation, and memory consolidation. The paper shows that Papez' circuit has the necessary connectivity to gather the various elements of an episodic memory occurring within Pöppel's experienced time or "quantum of experience". Finally, the paper shows how the memory engram located in Papez' circuit might be central to the formation of a duplicate engram in the cortex enabling consolidation and long-term storage of episodic memories.

7.
Heliyon ; 10(3): e24646, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38314264

RESUMEN

The demand for protein is increasing with an expanding world population and is influencing the rapid growth of fish and animal agriculture. These sectors are becoming a significant source of water pollution and need to develop environmentally sustainable techniques that are cost-effective, ideally with potential for downstream value-added production. This study investigated the potential of one of the fastest-growing cyanobacterial species, Synechococcus elongatus UTEX 2973, for bioremediation of mixed wastewater (combination of sturgeon and swine wastewater). Three different mixing ratios (25:75, 50:50, and 75:25 sturgeon:swine) were compared to find a suitable combination for the growth of S. elongatus as well as carbohydrate accumulation in biomass. The final biomass production was found to be 0.65 ± 0.03 g Dry cell Weight (DW)/L for 75%-25 %, 0.90 ± 0.004 g DW/L for 50%-50 %, and 0.71 ± 0.04 g DW/L for 25%-75 % sturgeon-swine wastewater combination. Cyanobacteria cultivated in 50%-50 % sturgeon-swine wastewater also accumulated 70 % total carbohydrate of DW, whereas 75%-25 % sturgeon-swine and 25%-75 % sturgeon-swine accumulated 53 % and 45 %, respectively. Subsequently, the S. elongatus cells were grown in a separate batch of 50%-50 % sturgeon-swine wastewater and compared with cells grown in BG11 synthetic growth media. Cultivation in BG11 resulted in higher biomass production but lower carbohydrate accumulation than 50%-50 % mixed wastewater. Final biomass production was 0.85 ± 0.08 g DW/L for BG11 and 0.65 ± 0.04 g DW/L for 50%-50 % sturgeon-swine wastewater. Total carbohydrate accumulated was 75 % and 64 % of DW for 50%-50 % sturgeon-swine mixed wastewater and BG11 growth media, respectively, where glycogen was the main carbohydrate component (90 %). The nutrient removal efficiencies of S. elongatus were 67.15 % for orthophosphate, 93.39 % for nitrate-nitrite, and 97.98 % for ammonia. This study suggested that S. elongatus is a promising candidate for enabling simultaneous bioremediation of mixed wastewater and the production of value-added biochemicals.

8.
Can J Nurs Res ; : 8445621241227720, 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38280214

RESUMEN

BACKGROUND: Policies and services for older adults are increasingly focused on living in the community, rather than relying on institutions. A total of 70-80% of community care for older adults is provided by family and friend caregivers. With Canada's aging population, the number of caregivers to older adults is growing. PURPOSE: The purpose of this paper is to describe the research methodology that was employed in the Saskatchewan Caregiver Experience Study. The methodology was used to map the experiences and gather perspectives of caregivers in Saskatchewan and to identify their priority support needs. METHODS: Qualitative description was the approach in this study. An online qualitative survey was administered via SurveyMonkey and distributed via Facebook and community newsletters. The survey collected caregiver demographics and asked three open-ended questions regarding: (1) the challenges that caregivers experience; (2) the positive aspects of caregiving; and (3) the support needs and priorities of Saskatchewan caregivers. A fourth question where caregivers could freely express any other experiences or perspectives was included. Content analysis was the method used for data analysis. RESULTS: 355 individuals met the inclusion criteria for this study. Participants were evenly distributed amongst urban-large, urban-small/medium, and rural settings in Saskatchewan. The average age of caregivers and care recipients were 61 and 83 respectively. CONCLUSION: This study has implications for research, practice, and policy. By gathering the full spectrum of the caregiver experience in Saskatchewan, this study can help to inform how communities, governments, and our healthcare system can best support caregivers in their role.

9.
Sci Rep ; 13(1): 21662, 2023 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-38066189

RESUMEN

Snakebite envenoming is a global public health issue that causes significant morbidity and mortality, particularly in low-income regions of the world. The clinical manifestations of envenomings vary depending on the snake's venom, with paralysis, haemorrhage, and necrosis being the most common and medically relevant effects. To assess the efficacy of antivenoms against dermonecrosis, a preclinical testing approach involves in vivo mouse models that mimic local tissue effects of cytotoxic snakebites in humans. However, current methods for assessing necrosis severity are time-consuming and susceptible to human error. To address this, we present the Venom Induced Dermonecrosis Analysis tooL (VIDAL), a machine-learning-guided image-based solution that can automatically identify dermonecrotic lesions in mice, adjust for lighting biases, scale the image, extract lesion area and discolouration, and calculate the severity of dermonecrosis. We also introduce a new unit, the dermonecrotic unit (DnU), to better capture the complexity of dermonecrosis severity. Our tool is comparable to the performance of state-of-the-art histopathological analysis, making it an accessible, accurate, and reproducible method for assessing dermonecrosis in mice. Given the urgent need to address the neglected tropical disease that is snakebite, high-throughput technologies such as VIDAL are crucial in developing and validating new and existing therapeutics for this debilitating disease.


Asunto(s)
Mordeduras de Serpientes , Ponzoñas , Humanos , Ratones , Animales , Mordeduras de Serpientes/terapia , Antivenenos/farmacología , Salud Global , Necrosis
10.
Nat Commun ; 14(1): 7812, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38097534

RESUMEN

Morbidity from snakebite envenoming affects approximately 400,000 people annually. Tissue damage at the bite-site often leaves victims with catastrophic life-long injuries and is largely untreatable by current antivenoms. Repurposed small molecule drugs that inhibit specific snake venom toxins show considerable promise for tackling this neglected tropical disease. Using human skin cell assays as an initial model for snakebite-induced dermonecrosis, we show that the drugs 2,3-dimercapto-1-propanesulfonic acid (DMPS), marimastat, and varespladib, alone or in combination, inhibit the cytotoxicity of a broad range of medically important snake venoms. Thereafter, using preclinical mouse models of dermonecrosis, we demonstrate that the dual therapeutic combinations of DMPS or marimastat with varespladib significantly inhibit the dermonecrotic activity of geographically distinct and medically important snake venoms, even when the drug combinations are delivered one hour after envenoming. These findings strongly support the future translation of repurposed drug combinations as broad-spectrum therapeutics for preventing morbidity caused by snakebite.


Asunto(s)
Mordeduras de Serpientes , Ratones , Humanos , Animales , Mordeduras de Serpientes/tratamiento farmacológico , Venenos de Serpiente/toxicidad , Venenos de Serpiente/uso terapéutico , Combinación de Medicamentos
11.
Glob Chang Biol ; 29(20): 5968-5980, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37448171

RESUMEN

Confidence in model estimates of soil CO2 flux depends on assumptions regarding fundamental mechanisms that control the decomposition of litter and soil organic carbon (SOC). Multiple hypotheses have been proposed to explain the role of lignin, an abundant and complex biopolymer that may limit decomposition. We tested competing mechanisms using data-model fusion with modified versions of the CN-SIM model and a 571-day laboratory incubation dataset where decomposition of litter, lignin, and SOC was measured across 80 soil samples from the National Ecological Observatory Network. We found that lignin decomposition consistently decreased over time in 65 samples, whereas in the other 15 samples, lignin decomposition subsequently increased. These "lagged-peak" samples can be predicted by low soil pH, high extractable Mn, and fungal community composition as measured by ITS PC2 (the second principal component of an ordination of fungal ITS amplicon sequences). The highest-performing model incorporated soil biogeochemical factors and daily dynamics of substrate availability (labile bulk litter:lignin) that jointly represented two hypotheses (C substrate limitation and co-metabolism) previously thought to influence lignin decomposition. In contrast, models representing either hypothesis alone were biased and underestimated cumulative decomposition. Our findings reconcile competing hypotheses of lignin decomposition and suggest the need to precisely represent the role of lignin and consider soil metal and fungal characteristics to accurately estimate decomposition in Earth-system models.


Asunto(s)
Lignina , Suelo , Suelo/química , Carbono/química
12.
Nat Commun ; 14(1): 2227, 2023 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-37076534

RESUMEN

Lignin is an abundant and complex plant polymer that may limit litter decomposition, yet lignin is sometimes a minor constituent of soil organic carbon (SOC). Accounting for diversity in soil characteristics might reconcile this apparent contradiction. Tracking decomposition of a lignin/litter mixture and SOC across different North American mineral soils using lab and field incubations, here we show that cumulative lignin decomposition varies 18-fold among soils and is strongly correlated with bulk litter decomposition, but not SOC decomposition. Climate legacy predicts decomposition in the lab, and impacts of nitrogen availability are minor compared with geochemical and microbial properties. Lignin decomposition increases with some metals and fungal taxa, whereas SOC decomposition decreases with metals and is weakly related with fungi. Decoupling of lignin and SOC decomposition and their contrasting biogeochemical drivers indicate that lignin is not necessarily a bottleneck for SOC decomposition and can explain variable contributions of lignin to SOC among ecosystems.


Asunto(s)
Carbono , Lignina , Suelo/química , Ecosistema , Clima , Microbiología del Suelo
13.
Sci Total Environ ; 877: 162837, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36924958

RESUMEN

Denitrification bioreactors are an effective edge-of-field conservation practice for nitrate (NO3) reduction from subsurface drainage. However, these systems may produce other pollutants and greenhouse gases during NO3 removal. Here a dual-chamber woodchip bioreactor system experiencing extreme low-flow conditions was monitored for its spatiotemporal NO3 and total organic carbon dynamics in the drainage water. Near complete removal of NO3 was observed in both bioreactor chambers in the first two years of monitoring (2019-2020) and in the third year of monitoring in chamber A, with significant (p < 0.01) reduction of the NO3-N each year in both chambers with 8.6-11.4 mg NO3-N L-1 removed on average. Based on the NO3 removal observed, spatial monitoring of sulfate (SO4), dissolved methane (CH4), and dissolved nitrous oxide (N2O) gases was added in the third year of monitoring (2021). In 2021, chambers A and B had median hydraulic residence times (HRTs) of 64 h and 39 h, respectively, due to varying elevations of the chambers, with drought conditions making the differences more pronounced. In 2021, significant production of dissolved CH4 was observed at rates of 0.54 g CH4-C m-3 d-1 and 0.07 g CH4-C m-3 d-1 in chambers A and B, respectively. In chamber A, significant removal (p < 0.01) of SO4 (0.23 g SO4 m-3 d-1) and dissolved N2O (0.21 mg N2O-N m-2 d-1) were observed, whereas chamber B produced N2O (0.36 mg N2O-N m-2 d-1). Considering the carbon dioxide equivalents (CO2e) on an annual basis, chamber A had loads (~12,000 kg CO2e ha-1 y-1) greater than comparable poorly drained agricultural soils; however, the landscape-scale impact was small (<1 % change in CO2e) when expressed over the drainage area treated by the bioreactor. Under low-flow conditions, pollution swapping in woodchip bioreactors can be reduced at HRTs <50 h and NO3 concentrations >2 mg N L-1.


Asunto(s)
Desnitrificación , Nitratos , Nitratos/análisis , Reactores Biológicos , Óxido Nitroso , Contaminación Ambiental
15.
J Environ Qual ; 52(3): 678-690, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36763775

RESUMEN

Much of the US Corn Belt has been drained with subsurface tile to improve crop production, yet poorly drained depressions often still flood intermittently, suppressing crop growth. Impacts of depressions on field-scale nutrient leaching are unclear. Poor drainage might promote denitrification and physicochemical retention of phosphorus (P), but ample availability of water and nutrients might exacerbate nutrient leaching from cropped depressions. We monitored nitrate, ammonium, and reactive P leaching across multiple depression-to-upland transects in north-central Iowa, using resin lysimeters buried and retrieved on an annual basis. Crops included conventional corn/soybean (Zea mays/Glycine max) rotations measured at fields with and without a winter rye (Secale cereale) cover crop, as well as juvenile miscanthus (Miscanthus × giganteus), a perennial grass. Leaching of nitrogen (N) and P was greater in depressions than in uplands for most transects and years. The median difference in nutrient leaching between paired depressions and uplands was 56 kg N ha-1 year-1 for nitrate (p = 0.0008), 0.6 kg N ha-1 year-1 for ammonium (p = 0.03), and 2.4 kg P ha-1 year-1 for reactive P (p = 0.006). Transects managed with a cover crop or miscanthus tended to have a smaller median difference in nitrate (but not ammonium or P) leaching between depressions and uplands. Cropped depressions may be disproportionate sources of N and P to downstream waters despite their generally poor drainage characteristics, and targeted management with cover crops or perennials might partially mitigate these impacts for N, but not necessarily for P.


Asunto(s)
Nitratos , Suelo , Nitratos/análisis , Depresión , Agricultura , Zea mays , Glycine max , Secale , Productos Agrícolas , Nitrógeno/análisis
16.
Can J Aging ; 42(1): 165-176, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36352769

RESUMEN

With increasing numbers of persons living with dementia and their higher rates of hospitalizations, it is necessary to ensure they receive appropriate and effective acute care; yet, acute care environments are often harmful for persons with dementia. There is a lack of dementia education for acute health care providers in Canada. Scotland presently delivers a dementia education program for health care providers, known as the Scottish National Dementia Champions Programme. The objective of this Policy and Practice Note is to present the collaborative work of Scottish experts and Canadian stakeholders to adapt the Dementia Champions Programme for use in Canada. This work to date includes: (a) an environmental scan of Canadian dementia education for acute health care providers; (b) key informant interviews; and, (c) findings from a two-day planning meeting. The results of this collaborative work can and are being used to inform the next steps to develop and pilot a Canadian dementia education program.


Asunto(s)
Demencia , Personal de Salud , Humanos , Canadá , Demencia/terapia , Escocia
17.
Health Soc Care Community ; 30(6): e3789-e3809, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36251430

RESUMEN

The vast majority of older adults who are chronically ill rely on informal caregivers for support. Caregivers often require additional support to facilitate their role. To the best of our knowledge, there has yet to be a collation of caregiver-identified priorities for support. Using existing research, this scoping review provides a comprehensive picture of what caregivers have indicated as priorities for support. Arksey and O'Malley's scoping review framework guides this review. We searched MEDLINE, CINAHL and PsycINFO databases on July 2, 2021. We selected databases based on their relevance to nursing, health and social science. Inclusion criteria were peer-reviewed research of any design, a sample population of caregivers to older adults (>55 years), manuscripts published in English and the priorities for caregiver support identified by caregivers themselves. We screened a total of 3591 records, and 33 articles met the inclusion criteria. These studies were from geographic settings across the globe and used various quantitative, qualitative and mixed-method study designs. In our synthesis, we quantified the identified priorities within the studies using coding and content analysis. We present the following list of caregiver-identified priorities: (1) orientation to the caregiving role; (2) self-care and respite; (3) adapting healthcare; (4) improved supports; (5) information needs; (6) access to resources; (7) financial assistance. Policymakers, healthcare professionals and non-profit organisations can use evidence from this review to guide decisions when developing support services and interventions for caregivers.


Asunto(s)
Cuidadores , Personal de Salud , Humanos , Anciano , Enfermedad Crónica , Proyectos de Investigación , Atención a la Salud
18.
Toxicon ; 220: 106955, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36309071

RESUMEN

Snakebite envenoming was reintroduced as a Category A Neglected Tropical Disease by the World Health Organization in 2017. Since then, increased attention has been directed towards this affliction and towards the development of a deeper understanding of how snake venoms exert their toxic effects and how antivenoms can counter them. However, most of our in vivo generated knowledge stems from the use of animal models which do not always accurately reflect how the pathogenic effects of snake venoms manifest in humans. Moreover, animal experiments are associated with pain, distress, and eventually animal sacrifice due to the toxic nature of snake venoms. Related to this, the implementation of the 3Rs principle (Replacement, Reduction, and Refinement) in the use of experimental animals in snakebite envenoming research is recommended by the World Health Organization. Therefore, more humane experimental designs and new in vitro/ex vivo alternatives for experimental animals are sought after. Here, we report the use of an organotypic model of human skin to further elucidate the pathophysiology of the dermonecrotic effects caused by the venom of the black-necked spitting cobra, Naja nigricollis, in humans. The goal of this study is to expand the repertoire of available models that can be used to study the local tissue damages induced by cytotoxic venoms.


Asunto(s)
Mordeduras de Serpientes , Animales , Humanos , Mordeduras de Serpientes/complicaciones , Proteómica , Venenos Elapídicos/toxicidad , Antivenenos/farmacología , Naja , Venenos de Serpiente
19.
PLoS Negl Trop Dis ; 16(9): e0010496, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36108067

RESUMEN

BACKGROUND: Snakebite is a major public health concern in Eswatini, where treatment relies upon one antivenom-SAIMR Polyvalent. Although effective in treating snakebite, SAIMR Polyvalent is difficult to source outside its manufacturing country (South Africa) and is dauntingly expensive. We compared the preclinical venom-neutralising efficacy of two alternative antivenoms with that of SAIMR Polyvalent against the lethal and tissue-destructive effects of venoms from five species of medically important snakes using in vivo murine assays. The test antivenoms were 'Panafrican' manufactured by Instituto Clodomiro Picado and 'PANAF' manufactured by Premium Serums & Vaccines. PRINCIPAL FINDINGS: In vivo murine preclinical studies identified both test antivenoms were equally or more effective than SAIMR Polyvalent at neutralising lethal and tissue-destructive effects of Naja mossambica venom. Both test antivenoms were less effective than SAIMR Polyvalent at neutralising the lethal effects of Bitis arietans, Dendroaspis polylepis, Hemachatus haemachatus and Naja annulifera venoms, but similarly effective at neutralising tissue damage induced by B. arietans and H. haemachatus venoms. In vitro immunological assays identified that the titres and toxin-specificities of immunoglobulins (iGs) in the test antivenoms were comparable to that of SAIMR Polyvalent. Plasma clotting disturbances by H. haemachatus and N. mossambica were neutralised by the test antivenoms, whereas SAIMR Polyvalent failed to neutralise this bioactivity of N. mossambica venom. B. arietans SVMP activity was equally reduced by all three antivenoms, and H. haemachatus and N. mossambica PLA2 activities were neutralised by all three antivenoms. CONCLUSIONS: While both Panafrican and PANAF antivenoms exhibited promising preclinical efficacies, both were less poly-specifically effective than SAIMR Polyvalent in these murine assays. The efficacy of these antivenoms against the lethal and tissue-destructive effects of N. mossambica venom, the most common biting species in Eswatini, identify that Panafrican and PANAF antivenoms offer effective alternatives to SAIMR Polyvalent for the treatment of snakebite in Eswatini, and potentially for neighbouring countries.


Asunto(s)
Mordeduras de Serpientes , Viperidae , Animales , Antivenenos/farmacología , Antivenenos/uso terapéutico , Esuatini , Ratones , Fosfolipasas A2 , Mordeduras de Serpientes/tratamiento farmacológico
20.
Can Geriatr J ; 25(3): 233-239, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36117744

RESUMEN

Background: An ageing population corresponds with a need for informal caregivers. Caregiving burden is the most compelling problem affecting caregivers of older adults. Previous research efforts have explored predictors of caregiving satisfaction and interventions for caregiving support. Our study aimed to set priorities for the future development of interventions for caregivers in Saskatchewan. Our objective was to engage caregivers in setting priorities for accessible interventions and support. The specific research question we sought to answer was: "What do the experiences of caregivers have to offer in setting priorities for caregiver support?" Methods: We conducted an environmental scan of caregiver intervention programming in Canada. We then held two focus groups with caregivers to older adults, defined as 55 years or older for this study. Twenty-three caregivers attended the first focus group, and 10 caregivers participated in the second. We used a qualitative descriptive approach and data were analyzed using thematic analysis. Results: Caregivers of older adults were eager to share barriers and facilitators of their role. Themes derived from data include: 1) lack of access; 2) conflict with self and others; 3) the burden of caregiving; and 4) declining health and wellness. Conclusion: Caregivers may struggle to find resources to support them in their caregiving role. Findings from this study indicate that there is a need for more interventions to support caregivers. Furthermore, our data highlight what outcomes caregivers in Saskatchewan want from those interventions.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...