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1.
Healthcare (Basel) ; 12(8)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38667588

RESUMO

Pregnancy and childbirth have a great impact on women's lives; traumatic perinatal experiences can adversely affect mental health. The present study analyzes the incidence of perinatal post-traumatic stress disorder (PTSD) in Catalonia in 2021 from data obtained from the Registry of Morbidity and Use of Health Resources of Catalonia (MUSSCAT). The incidence of perinatal PTSD (1.87%) was lower than in comparable studies, suggesting underdiagnosis. Poisson regression adjusting for age, income, gestational weeks at delivery, type of delivery, and parity highlighted the influence of sociodemographics, and characteristics of the pregnancy and delivery on the risk of developing perinatal PTSD. These findings underline the need for further research on the risk factors identified and for the early detection and effective management of PTSD in the perinatal setting.

2.
Neuropharmacology ; 249: 109871, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38412889

RESUMO

Dopamine is unable to access the central nervous system through the bloodstream. Only its precursor can do so, and with an effectiveness below 100% of the dose administered, as it is metabolized before crossing the blood-brain barrier. In this study, we describe a new solid lipid nanocarrier system designed and developed for dopamine. The nanoparticles were prepared by the melt-emulsification method and then coated with chitosan. The nanocarriers developed had a droplet size of about 250 nm, a polydispersity index of 0.2, a positive surface charge (+30 mV), and a percentage encapsulation efficiency of 36.3 ± 5.4. Transmission and scanning electron microscopy verified uniformity of particle size with spherical morphology. Various types of tests were performed to confirm that the nanoparticles designed are suitable for carrying dopamine through the blood-brain barrier. In vitro tests demonstrated the ability of these nanocarriers to pass through endothelial cell monolayers without affecting their integrity. This study shows that the formulation of dopamine in chitosan-coated solid lipid nanoparticles is a potentially viable formulation strategy to achieve the bioavailability of the drug for the treatment of Parkinson's disease in the central nervous system.


Assuntos
Quitosana , Lipossomos , Nanopartículas , Portadores de Fármacos/metabolismo , Dopamina/metabolismo , Quitosana/metabolismo , Barreira Hematoencefálica/metabolismo
3.
J Med Entomol ; 61(2): 504-507, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38195205

RESUMO

The invasive tick, Haemaphysalis longicornis Neumann, is now present across most of the mid-Atlantic States in the eastern United States. This tick ends its seasonal activity in late October to early November, with larvae being the last life-stage observed questing. Previous research has revealed that the activity of H. longicornis is influenced by photoperiod: short daylight lengths trigger diapause in nymphs, marking it as the primary overwintering stage. However, whether engorged larvae can enter diapause or are affected by short daylight is unclear. In this study, we tested in the laboratory whether the photoperiod Affects the development of H. longicornis engorged larvae and engorged nymphs under constant temperature and humidity. The results showed that engorged larvae molted significantly faster (3 days faster) when the photoperiod was 9 h of light as opposed to 14 h. In contrast, changes in the photoperiod did not affect the molting of engorged nymphs. Our results demonstrate that engorged larvae respond to short daylight length, by molting faster. These results suggest that engorged larvae are unlikely to overwinter under field conditions and support the expectation that nymphs are the primary overwintering stage for H. longicornis in the United States.


Assuntos
Ixodidae , Carrapatos , Animais , 60614 , Fotoperíodo , Temperatura , Larva , Ninfa
4.
Int J Mol Sci ; 25(2)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38255772

RESUMO

Parkinson's disease (PD) is a complex disorder characterized by the impairment of the dopaminergic nigrostriatal system. PD has duplicated its global burden in the last few years, becoming the leading neurological disability worldwide. Therefore, there is an urgent need to develop innovative approaches that target multifactorial underlying causes to potentially prevent or limit disease progression. Accumulating evidence suggests that neuroinflammatory responses may play a pivotal role in the neurodegenerative processes that occur during the development of PD. Cortistatin is a neuropeptide that has shown potent anti-inflammatory and immunoregulatory effects in preclinical models of autoimmune and neuroinflammatory disorders. The goal of this study was to explore the therapeutic potential of cortistatin in a well-established preclinical mouse model of PD induced by acute exposure to the neurotoxin 1-methil-4-phenyl1-1,2,3,6-tetrahydropyridine (MPTP). We observed that treatment with cortistatin mitigated the MPTP-induced loss of dopaminergic neurons in the substantia nigra and their connections to the striatum. Consequently, cortistatin administration improved the locomotor activity of animals intoxicated with MPTP. In addition, cortistatin diminished the presence and activation of glial cells in the affected brain regions of MPTP-treated mice, reduced the production of immune mediators, and promoted the expression of neurotrophic factors in the striatum. In an in vitro model of PD, treatment with cortistatin also demonstrated a reduction in the cell death of dopaminergic neurons that were exposed to the neurotoxin. Taken together, these findings suggest that cortistatin could emerge as a promising new therapeutic agent that combines anti-inflammatory and neuroprotective properties to regulate the progression of PD at multiple levels.


Assuntos
Neuropeptídeos , Doença de Parkinson , Animais , Camundongos , Doença de Parkinson/tratamento farmacológico , Neurotoxinas , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico
5.
Heliyon ; 10(1): e23969, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38259962

RESUMO

Surface treatments help to protect the built heritage against damage (environmental, accidental, etc.), reducing repair and restitution costs and increasing the useful life of building materials. The use of nanomaterials is currently the most important field of research in surface treatment technology for the preservation of building materials and, more specifically, to improve their durability and prevent their deterioration, extending their useful life. This paper studies the influence of a graphene oxide (GO) suspension as a surface treatment on the properties of concrete. The results indicate that, at best, surface treatment with GO can decrease both the water absorption and capillary absorption of concrete by about 15 %. The increase in the amount of GO deposited as a surface treatment leads to a further reduction in concrete water absorption. It is shown that, at best, GO coating also reduces water penetration at low and high pressures by approximately 20 % and 60 %, respectively. In addition, scanning electron microscopy analysis shows that GO surface treatment facilitates the hydration process and densifies the concrete microstructure. A simple aqueous suspension of GO is revealed as a tool with a high potential to protect concrete surfaces in a fast and cost-effective way, thanks to the easy application by spraying and the small amount of material needed to obtain great results.

6.
Nutrients ; 16(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38257141

RESUMO

Many patients undergo small bowel and colon surgery for reasons related to malignancy, inflammatory bowel disease (IBD), mesenteric ischemia, and other benign conditions, including post-operative adhesions, hernias, trauma, volvulus, or diverticula. Some patients arrive in the operating theatre severely malnourished due to an underlying disease, while others develop complications (e.g., anastomotic leaks, abscesses, or strictures) that induce a systemic inflammatory response that can increase their energy and protein requirements. Finally, anatomical and functional changes resulting from surgery can affect either nutritional status due to malabsorption or nutritional support (NS) pathways. The dietitian providing NS to these patients needs to understand the pathophysiology underlying these sequelae and collaborate with other professionals, including surgeons, internists, nurses, and pharmacists. The aim of this review is to provide an overview of the nutritional and metabolic consequences of different types of lower gastrointestinal surgery and the role of the dietitian in providing comprehensive patient care. This article reviews the effects of small bowel resection on macronutrient and micronutrient absorption, the effects of colectomies (e.g., ileocolectomy, low anterior resection, abdominoperineal resection, and proctocolectomy) that require special dietary considerations, nutritional considerations specific to ostomized patients, and clinical practice guidelines for caregivers of patients who have undergone a surgery for local and systemic complications of IBD. Finally, we highlight the valuable contribution of the dietitian in the challenging management of short bowel syndrome and intestinal failure.


Assuntos
Doenças Inflamatórias Intestinais , Distúrbios Nutricionais , Nutricionistas , Humanos , Colectomia
7.
Infect Immun ; 92(1): e0024423, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38099660

RESUMO

Interactions among pathogen genotypes that vary in host specificity may affect overall transmission dynamics in multi-host systems. Borrelia burgdorferi, a bacterium that causes Lyme disease, is typically transmitted among wildlife by Ixodes ticks. Despite the existence of many alleles of B. burgdorferi's sensu stricto outer surface protein C (ospC) gene, most human infections are caused by a small number of ospC alleles ["human infectious alleles" (HIAs)], suggesting variation in host specificity associated with ospC. To characterize the wildlife host association of B. burgdorferi's ospC alleles, we used metagenomics to sequence ospC alleles from 68 infected individuals belonging to eight mammalian species trapped at three sites in suburban New Brunswick, New Jersey (USA). We found that multiple allele ("mixed") infections were common. HIAs were most common in mice (Peromyscus spp.) and only one HIA was detected at a site where mice were rarely captured. ospC allele U was exclusively found in chipmunks (Tamias striatus), and although a significant number of different alleles were observed in chipmunks, including HIAs, allele U never co-occurred with other alleles in mixed infections. Our results suggest that allele U may be excluding other alleles, thereby reducing the capacity of chipmunks to act as reservoirs for HIAs.


Assuntos
Borrelia burgdorferi , Borrelia , Coinfecção , Ixodes , Doença de Lyme , Animais , Humanos , Borrelia burgdorferi/genética , Borrelia/genética , Alelos , Doença de Lyme/microbiologia , Ixodes/genética , Ixodes/microbiologia , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Sciuridae/genética , Especificidade de Hospedeiro
8.
Rev. mex. trastor. aliment ; 13(2): 134-144, jul.-dic. 2023. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1530224

RESUMO

Resumen: Los trastornos de la conducta alimentaria son de las enfermedades crónicas más frecuentes en adolescentes y mujeres jóvenes. En México se han encontrado porcentajes desde 5 hasta 18% de conductas alimentarias de riesgo en muestras de mujeres estudiantes universitarias (Unikel-Santoncini, et al., 2004). Por otro lado, la resiliencia se define como un constructo que incluye ciertos fenómenos que consisten en la adecuada adaptación del individuo ante situaciones traumáticas, privación extrema, amenazas graves o estrés elevado (González-Arratia, 2008, en Camacho-Valadez, 2016). Esta investigación examina la relación entre la resiliencia y las conductas alimentarias de riesgo por medio de la aplicación de los instrumentos EAT-26 y RESI-M a 201 mujeres mexicanas, con un promedio de edad de 22 años. Se realizó un análisis de correlación de Producto Momento de Pearson, el cual demostró que, aquellas mujeres con mayores niveles de resiliencia mostraban menos conductas alimentarias de riesgo. Se propone realizar el mismo estudio con poblaciones más jóvenes, así como con participantes de sexo masculino.


Abstract: Eating disorders are one of the most frequent chronic diseases in adolescents and young women. In Mexico, percentages from 5 to 18% of risk eating behaviors have been found in samples of female university students (Unikel-Santoncini, et al., 2004). On the other hand, resilience is defined as a construct that includes certain phenomena that consist of the individual's adequate adaptation to traumatic situations, extreme deprivation, serious threats, or high stress (González-Arratia, 2008, in Camacho Valadez, 2016). This research examines the relationship between resilience and risk eating behaviors through the application of the EAT-26 and RESI-M instruments to 201 Mexican women, with an average age of 22 years. A Pearson Product Moment correlation analysis was performed, which showed that those women with higher levels of resilience showed less risk eating behaviors. It's proposed to carry out the same study with younger populations, as well as with male participants.

10.
J Neuroinflammation ; 20(1): 226, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794493

RESUMO

BACKGROUND: Brain activity governing cognition and behaviour depends on the fine-tuned microenvironment provided by a tightly controlled blood-brain barrier (BBB). Brain endothelium dysfunction is a hallmark of BBB breakdown in most neurodegenerative/neuroinflammatory disorders. Therefore, the identification of new endogenous molecules involved in endothelial cell disruption is essential to better understand BBB dynamics. Cortistatin is a neuroimmune mediator with anti-inflammatory and neuroprotective properties that exerts beneficial effects on the peripheral endothelium. However, its role in the healthy and injured brain endothelium remains to be evaluated. Herein, this study aimed to investigate the potential function of endogenous and therapeutic cortistatin in regulating brain endothelium dysfunction in a neuroinflammatory/neurodegenerative environment. METHODS: Wild-type and cortistatin-deficient murine brain endothelium and human cells were used for an in vitro barrier model, where a simulated ischemia-like environment was mimicked. Endothelial permeability, junction integrity, and immune response in the presence and absence of cortistatin were evaluated using different size tracers, immunofluorescence labelling, qPCR, and ELISA. Cortistatin molecular mechanisms underlying brain endothelium dynamics were assessed by RNA-sequencing analysis. Cortistatin role in BBB leakage was evaluated in adult mice injected with LPS. RESULTS: The endogenous lack of cortistatin predisposes endothelium weakening with increased permeability, tight-junctions breakdown, and dysregulated immune activity. We demonstrated that both damaged and uninjured brain endothelial cells isolated from cortistatin-deficient mice, present a dysregulated and/or deactivated genetic programming. These pathways, related to basic physiology but also crucial for the repair after damage (e.g., extracellular matrix remodelling, angiogenesis, response to oxygen, signalling, and metabolites transport), are dysfunctional and make brain endothelial barrier lacking cortistatin non-responsive to any further injury. Treatment with cortistatin reversed in vitro hyperpermeability, tight-junctions disruption, inflammatory response, and reduced in vivo BBB leakage. CONCLUSIONS: The neuropeptide cortistatin has a key role in the physiology of the cerebral microvasculature and its presence is crucial to develop a canonical balanced response to damage. The reparative effects of cortistatin in the brain endothelium were accompanied by the modulation of the immune function and the rescue of barrier integrity. Cortistatin-based therapies could emerge as a novel pleiotropic strategy to ameliorate neuroinflammatory/neurodegenerative disorders with disrupted BBB.


Assuntos
Encefalopatias , Neuropeptídeos , Camundongos , Animais , Humanos , Células Endoteliais/metabolismo , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Endotélio , Neuropeptídeos/metabolismo
11.
Parasitology ; 150(11): 1063-1069, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37791496

RESUMO

Piroplasms, which include the agents of cattle fever and human and dog babesiosis, are a diverse group of blood parasites of significant veterinary and medical importance. The invasive Asian longhorned tick, Haemaphysalis longicornis, is a known vector of piroplasms in its native range in East Asia and invasive range in Australasia. In the USA, H. longicornis has been associated with Theileria orientalis Ikeda outbreaks that caused cattle mortality. To survey invasive populations of H. longicornis for a broad range of piroplasms, 667 questing H. longicornis collected in 2021 from 3 sites in New Jersey, USA, were tested with generalist piroplasm primers targeting the 18S small subunit rRNA (395­515 bp, depending on species) and the cytochrome b oxidase loci (1009 bp). Sequences matching Theileria cervi type F (1 adult, 5 nymphs), an unidentified Theileria species (in 1 nymph), an undescribed Babesia sensu stricto ('true' Babesia, 2 adults, 2 nymphs), a Babesia sp. Coco (also a 'true Babesia', 1 adult, 1 nymph), as well as Babesia microti S837 (1 adult, 4 nymphs) were recovered. Babesia microti S837 is closely related to the human pathogen B. microti US-type. Additionally, a 132 bp sequence matching the cytochrome b locus of deer, Odocoileus virginanus, was obtained from 2 partially engorged H. longicornis. The diverse assemblage of piroplasms now associated with H. longicornis in the USA spans 3 clades in the piroplasm phylogeny and raises concerns of transmission amplification of veterinary pathogens as well as spillover of pathogens from wildlife to humans.


Assuntos
Apicomplexa , Babesia , Cervos , Ixodidae , Parasitos , Piroplasmida , Theileria , Carrapatos , Animais , Estados Unidos/epidemiologia , Humanos , Cães , Bovinos , Piroplasmida/genética , Ixodidae/genética , Carrapatos/parasitologia , Parasitos/genética , Citocromos b , Apicomplexa/genética , Babesia/genética , Theileria/genética , RNA Ribossômico 18S/genética , Ninfa/parasitologia
12.
Int J Mol Sci ; 24(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37762420

RESUMO

Neurodegenerative disorders encompass a broad spectrum of profoundly disabling situations that impact millions of individuals globally. While their underlying causes and pathophysiology display considerable diversity and remain incompletely understood, a mounting body of evidence indicates that the disruption of blood-brain barrier (BBB) permeability, resulting in brain damage and neuroinflammation, is a common feature among them. Consequently, targeting the BBB has emerged as an innovative therapeutic strategy for addressing neurological disorders. Within this review, we not only explore the neuroprotective, neurotrophic, and immunomodulatory benefits of mesenchymal stem cells (MSCs) in combating neurodegeneration but also delve into their recent role in modulating the BBB. We will investigate the cellular and molecular mechanisms through which MSC treatment impacts primary age-related neurological conditions like Alzheimer's disease, Parkinson's disease, and stroke, as well as immune-mediated diseases such as multiple sclerosis. Our focus will center on how MSCs participate in the modulation of cell transporters, matrix remodeling, stabilization of cell-junction components, and restoration of BBB network integrity in these pathological contexts.


Assuntos
Doença de Alzheimer , Células-Tronco Mesenquimais , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Barreira Hematoencefálica/patologia , Doenças Neurodegenerativas/patologia , Doença de Parkinson/patologia , Doença de Alzheimer/patologia , Células-Tronco Mesenquimais/fisiologia
13.
Birth ; 50(4): 1057-1067, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37589398

RESUMO

BACKGROUND: Midwife-led units have been shown to be safer and reduce interventions for women at low risk of complications at birth. In 2017, the first alongside birth center was opened in Spain. The aim of this study was to compare outcomes for women with uncomplicated pregnancies giving birth in the Midwife-led unit (MLU) and in the Obstetric unit (OU) of the same hospital. METHODS: Retrospective cohort study comparing birth outcomes between low-risk women, depending on their planned place of birth. Data were analyzed with an intention-to-treat approach for women that gave birth between January 2018 and December 2020. RESULTS: A total of 878 women were included in the study, 255 women chose to give birth in the MLU and 623 in the OU. Findings showed that women in the MLU were more likely to have a vaginal birth (91.4%) than in the OU (83.8%) (aOR 2.98 [95%CI 1.62-5.47]), less likely to have an instrumental delivery, 3.9% versus 11.2% (0.25 [0.11-0.55]), to use epidural analgesia, 19.6% versus 77.9% (0.15 [0.04-0.17]) and to have an episiotomy, 7.4% versus 15.4% (0.27 [0.14-0.53]). There were no differences in rates of postpartum hemorrhage, retained placenta, or adverse neonatal outcomes. Intrapartum and postpartum transfer rates from the MLU to the OU were 21.1% and 2.4%, respectively. CONCLUSIONS: The high rate of obstetric interventions in Spain could be reduced by implementing midwife-led units across the whole system, without an increase in maternal or neonatal complications.


Assuntos
Tocologia , Recém-Nascido , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Espanha/epidemiologia , Parto Obstétrico , Episiotomia
14.
Trends Parasitol ; 39(10): 873-885, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37591719

RESUMO

Ticks can transmit a variety of human pathogens, including intracellular and extracellular bacteria, viruses, and protozoan parasites. Historically, their saliva has been of immense interest due to its anticoagulant, anti-inflammatory, and anesthetic properties. Only recently, it was discovered that tick saliva contains extracellular vesicles (EVs). Briefly, it has been observed that proteins associated with EVs are important for multiple tick-borne intracellular microbial lifestyles. The impact of tick EVs on viral and intracellular bacterial pathogen transmission from the tick to the mammalian host has been shown experimentally. Additionally, tick EVs interact with the mammalian skin immune system at the bite site. The interplay between tick EVs, the transmission of pathogens, and the host skin immune system affords opportunities for future research.


Assuntos
Vesículas Extracelulares , Pele , Humanos , Animais , Saliva , Mamíferos
15.
Int J Parasitol ; 53(14): 809-819, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37467875

RESUMO

The northeastern United States (US) is a hotspot for tick-borne diseases. Adding to an already complex vector landscape, in 2017 large populations of the invasive Haemaphysalis longicornis, the Asian longhorned tick, were detected in New Jersey (NJ) and later found to be widespread from Connecticut to Georgia. In its native range in northeastern Asia, H. longicornis is considered an important vector of deadly pathogens to humans, companion animals, and livestock. To identify the primary hosts of H. longicornis, we surveyed synanthropic small and medium-sized mammals in three different sites in suburban New Brunswick, NJ. Specifically, we collected approximately 9,000 tick specimens belonging to nine species from 11 different species of mammals sampled between May and September 2021. We found that H. longicornis feeds more frequently on rodents than previously thought, and that this invasive tick is likely exposed to important enzootic and zoonotic pathogens. Overall, we obtained detailed information about the seasonal dynamics and feeding patterns of six tick species common in the northeastern US, Haemaphysalis longicornis, Amblyomma americanum, Dermacentor variabilis, Ixodes scapularis, Ixodes texanus and Ixodes cookei. We found that unlike I. scapularis that feeds on mammals of all sizes, H. longicornis feeds on hosts following the general pattern of A. americanum, favoring larger species such as skunks, groundhogs, and raccoons. However, our survey revealed that unlike A. americanum, H. longicornis reaches high densities on Virginia opossum. Overall, the newly invasive H. longicornis was the most numerous tick species, both on multiple host species and in the environment, raising significant questions regarding its role in the epidemiology of tick-borne pathogens, especially those affecting livestock, companion animals and wildlife. In conclusion, our findings provide valuable insights into the tick species composition on mammalian hosts in NJ and the ongoing national expansion of H. longicornis.


Assuntos
Didelphis , Ixodes , Ixodidae , Infestações por Carrapato , Animais , Humanos , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Mamíferos , New England
16.
Pest Manag Sci ; 79(11): 4328-4334, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37366176

RESUMO

BACKGROUND: The Asian longhorned tick, Haemaphysalis longicornis, continues to expand its range in North America, and synthetic acaricides are likely to play an increasing role in managing this species. Acaricide resistance is common in some tick species that infest livestock. However, baseline acaricide susceptibility has not previously been examined in this invasive tick. RESULTS: We used a standard larval packet test to evaluate the susceptibility of the Asian longhorned tick to acaricides currently or formerly used in tick control: propoxur, carbaryl, bifenthrin, permethrin, and coumaphos. Discriminating concentrations were estimated at 6.5, 27.9, 988, 2242, and 808 ppm, respectively. The half-maximal lethal concentration (LC50 ) values for propoxur, carbaryl, permethrin and coumaphos were compared with data available for other tick species and showed that H. longicornis was more susceptible to propoxur, carbaryl and coumaphos, and had a similar susceptibility to permethrin. CONCLUSIONS: The results indicate that resistance to these acaricides is not currently a concern for H. longicornis in the United States. However, responsible integrated management and early detection of resistance can help ensure the long-term efficacy of products used for controlling this tick species. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

18.
ACS Appl Energy Mater ; 6(2): 1085-1092, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36937111

RESUMO

Recently, the development of durable anion-exchange membrane fuel cells (AEMFCs) has increased in intensity due to their potential to use low-cost, sustainable components. However, the decomposition of the quaternary ammonium (QA) cationic groups in the anion-exchange membranes (AEMs) during cell operation is still a major challenge. Many different QA types and functionalized polymers have been proposed that achieve high AEM stabilities in strongly alkaline aqueous solutions. We previously developed an ex situ technique to measure AEM alkaline stabilities in an environment that simulates the low-hydration conditions in an operating AEMFC. However, this method required the AEMs to be soluble in DMSO solvent, so decomposition could be monitored using 1H nuclear magnetic resonance (NMR). We now report the extension of this ex situ protocol to spectroscopically measure the alkaline stability of insoluble AEMs. The stability ofradiation-grafted (RG) poly(ethylene-co-tetrafluoroethylene)-(ETFE)-based poly(vinylbenzyltrimethylammonium) (ETFE-TMA) and poly(vinylbenzyltriethylammonium) (ETFE-TEA) AEMs were studied using Raman spectroscopy alongside changes in their true OH- conductivities and ion-exchange capacities (IEC). A crosslinked polymer made from poly(styrene-co-vinylbenzyl chloride) random copolymer and N,N,N',N'-tetraethyl-1,3-propanediamine (TEPDA) was also studied. The results are consistent with our previous studies based on QA-type model small molecules and soluble poly(2,6-dimethylphenylene oxide) (PPO) polymers. Our work presents a reliable ex situ technique to measure the true alkaline stability of AEMs for fuel cells and water electrolyzers.

19.
Insects ; 14(3)2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36975943

RESUMO

People often use parks and other forested areas for outdoor activities such as hiking and walking their dogs. Areas of primary use are paths or grassy meadows on the edges of the forests that constitute transitional areas between different plant communities (aka ecotones). In this study, we monitored the seasonal dynamics of questing ticks in forest/meadow and forest/path ecotones in five areas in Middlesex County, New Jersey (NJ). We found anthropophilic species such as Ixodes scapularis, Amblyomma americanum, and Dermacentor variabilis coexisting with Haemaphysalis longicornis, an invasive tick species first detected in NJ in 2017. Surveillance was conducted weekly from March to November 2020, and collected ticks were identified. The most abundant tick species was H. longicornis (83%), followed by A. americanum (9%), I. scapularis (7%), and D. variabilis (<1%). The seasonal dynamics of A. americanum and I. scapularis in the ecotone were similar to previous surveys in forest habitats. The presence of anthropophilic ticks, particularly I. scapularis, suggests the need for specific control approaches to target these habitats. In addition, the extraordinarily high numbers of H. longicornis collected in ecotones (1.70 ticks/m2) and frequent reports of this species on dogs highlight the importance of monitoring its expansion due to its potential as a vector of animal and human diseases.

20.
Ticks Tick Borne Dis ; 14(3): 102157, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36917863

RESUMO

The soft ticks (Argasidae) are known vectors of human and animal pathogens around the globe and are relatively understudied. Our aim was to assess the presence of Rickettsia and Borrelia bacteria in Alectorobius kelleyi (Argasidae) parasitizing synanthropic bats in the highly urbanized northeastern United States. By collaborating with parasitologists, bat scientists and wildlife rehabilitators we were successful in obtaining A. kelleyi from five states. Since Argasid larvae will attach to their hosts for many days, most A. kelleyi examined (92%) were larvae collected from sick or injured big brown bats, Eptesicus fuscus, undergoing care at rehabilitation centers. In addition, we obtained adult A. kelleyi captured in residential living areas and trapped in attics. An in-depth analysis of a A. kelleyi found to be infected with a spotted fever group Rickettsia (SFGR) revealed a dual infection with a R. belli-like taxon (ancestral group) as well as an SFGR closely related to R. peacockii, likely the same previously found in A. kelleyi from Iowa and Kansas. We found that 36% of the A. kelleyi tested carried the SFGR. Furthermore, we detected a relapsing fever spirochete, likely Candidatus Borrelia johnsonii, in 25% of the A. kelleyi from Pennsylvania. While it is unclear if these bacteria constitute a health risk to either bats or humans, our study indicates that human exposure to ectoparasites infesting peridomestic wildlife should be considered in the epidemiology of tick-borne diseases.


Assuntos
Argasidae , Borrelia , Quirópteros , Ornithodoros , Febre Recorrente , Rickettsia , Adulto , Animais , Humanos , Argasidae/microbiologia , Quirópteros/parasitologia , Febre Recorrente/epidemiologia , Febre Recorrente/veterinária , Ornithodoros/microbiologia , Animais Selvagens
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