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1.
Biodivers Data J ; 12: e115464, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38586529

RESUMO

Background: With this publication, we contribute to the knowledge of the arachnofauna of Cabo Verde, focusing specifically on the Islands of Santo Antão and São Vicente. Data were obtained from samples collected as part of the project "Macaronesian Islands as a testing ground to assess biodiversity drivers at multiple scales" (FCT - MACDIV, 2015-2018). This project aimed to identify the factors influencing community assembly in Macaronesian islands. For the Cabo Verde Islands, we focused on dry habitats with the additional aim to revise the aracnofauna of this poorly-known fauna. We applied the COBRA (Conservation Oriented Biodiversity Rapid Assessment) sampling protocol in ten 50 m x 50 m dry shrub plots, with five on each of the two islands, using pitfall traps, sweep-netting and active search. Additional ad-hoc samples were also collected and reported. New information: Our sampling of spiders from Cabo Verde (Santo Antão and São Vicente) yielded a total of 3,368 specimens, of which 1300 (39%) were adults. The samples include 21 families, 87 species, 18 of which are morphospecies awaiting formal identification or description at species level. Species in the families Oxyopidae (2 spp.) and Araneidae (8 spp.) were the most abundant, making up 49% of the specimens. From the 68 named species, 14 are endemic to Cabo Verde, 40 are native non-endemic and 14 are introduced. The colonisation status of Cithaeronreimoseri Platnick, 1991 is unknown. Endemic species accounted for 24% (n = 818) of the specimens and native non-endemic for 63% (n = 2122). A total of 29 species were new records for Cabo Verde, with 15 for Santo Antão, seven for São Vicente and seven for both Islands.

2.
Org Biomol Chem ; 21(32): 6595-6603, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37530577

RESUMO

Calix[4]pyrroles bearing hydroxyl (1) or urea (3) groups attached to the meso-positions with propyl linkers were synthesized as cis- and trans-isomers. The anion binding properties of cis-1 and cis-3 were screened with ion-mobility mass spectrometry, where cis-1 formed complexes with Cl-, Br- and H2PO4-, whereas cis-3 formed complexes with most of the investigated anions, including Cl-, Br-, I-, NO3-, ClO4-, OTf-, SCN- and PF6-. The structures of the chloride complexes were further elucidated with density functional theory calculations and a crystal structure obtained for cis-1. In solution, chloride and dihydrogenphosphate anion binding with cis-1 and cis-3 were compared using 1H NMR titrations. To assess the suitability of two-armed calix[4]pyrroles as anion transporters, chloride transport studies of cis-1, cis-3 and trans-3 were performed using large unilamellar vesicles. The results revealed that cis-3 had the highest activity among the investigated calix[4]pyrroles, which was related to the improved affinity and isolation of chloride inside the binding cavity of cis-3 in comparison to cis-1. The results indicate that appending calix[4]pyrroles with two hydrogen bonding arms is a feasible strategy to obtain anion transporters and receptors with high anion affinity.

3.
Angew Chem Int Ed Engl ; 62(38): e202307841, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37429824

RESUMO

Relaying conformational change over several nanometers is central to the function of allosterically regulated proteins. Replicating this mechanism artificially would provide important communication tools, but requires nanometer-sized molecules that reversibly switch between defined shapes in response to signaling molecules. In this work, 1.8 nm long rigid rod oligo(phenylene-ethynylene)s are scaffolds for switchable multi-squaramide hydrogen-bond relays. Each relay can adopt either a parallel or an antiparallel orientation relative to the scaffold; the preferred orientation is dictated by a director group at one end. An amine director responded to proton signals, with acid-base cycles producing multiple reversible changes in relay orientation that were reported by a terminal NH, which is 1.8 nm distant. Moreover, a chemical fuel acted as a dissipative signal. As the fuel was consumed, the relay reverted to its original orientation, illustrating how information from out-of-equilibrium molecular signals can be communicated to a distant site.

4.
Phys Chem Chem Phys ; 25(27): 18121-18131, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37382482

RESUMO

Thiourea-based receptors for anions have been widely studied due to their ability to transport anions across phospholipid bilayers. The binding affinity of a tripodal thiourea-based receptor for anions was assessed at the aqueous|organic interface using electrochemical measurements. A 1 : 1 stoichiometry was determined for the complexation of most anions, with a higher stoichiometry found in the presence of excess Cl- and Br- anions. High stability constants were estimated for the formation of the complexes at the aqueous|1,2-dichlorobenzene (DCB) interface. When compared with an organic solvent of higher polarity, nitrobenzene (NB), the high stability constants observed in DCB are believed to be due to the less competitive environment of the less polar solvent. Protonation of the receptor at the bridgehead tertiary amine was also inferred from the potential-dependent voltammetric measurements that are not related to anion:receptor complexation. The inherent advantages of the electrochemical method with the use of low polarity solvents are expected to provide new insights into the binding and transport of newly-developed neutral receptors.

5.
Org Lett ; 25(19): 3423-3428, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37158572

RESUMO

Simple, clean and fast photoconversion of aniline-derived squaramides was achieved by flashlight illumination. UV irradiation enabled the photochemical squaramide ring-opening to generate 1,2-bisketenes, which DMSO trapped as the nucleophilic oxidant. The only photoproducts isolated were 3,4-arylamino maleic anhydrides, which present conformational preferences very different from those of their parent squaramides. Similar photoconversion was achieved in MeOH. The UV-mediated time-dependent anion transport inhibition was demonstrated, establishing a new approach for modulating the transport abilities of AD-squaramides.

6.
Chempluschem ; 87(11): e202200266, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36414387

RESUMO

The development of synthetic anion transporters is motivated by their potential application as treatment for diseases that originate from deficient anion transport by natural proteins. Transport of bicarbonate is important for crucial biological functions such as respiration and digestion. Despite this biological relevance, bicarbonate transport has not been as widely studied as chloride transport. Herein we present an overview of the synthetic receptors that have been studied as bicarbonate transporters, together with the different assays used to perform transport studies in large unilamellar vesicles. We highlight the most active transporters and comment on the nature of the functional groups present in active and inactive compounds. We also address recent mechanistic studies that have revealed different processes that can lead to net transport of bicarbonate, as well as studies reported in cells and tissues, and comment on the key challenges for the further development of bicarbonate transporters.


Assuntos
Bicarbonatos , Transporte Biológico , Transporte de Íons
7.
J Org Chem ; 87(15): 9829-9838, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35862261

RESUMO

Bambusurils are macrocyclic molecules that are known for their high binding affinity and selectivity toward anions. Here, we present the preparation of two bambusurils bearing fluorinated substituents and one carboxylic function. These monofunctionalized bambusurils were conjugated with crown ether and cholesterol units. The resulting conjugates were successfully tested in liquid-liquid extraction of inorganic salts and chloride/bicarbonate transport across lipid bilayers.


Assuntos
Cloretos , Éteres de Coroa , Ânions/química , Cloretos/química , Bicamadas Lipídicas/química
8.
Chem Commun (Camb) ; 58(42): 6255-6258, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35521967

RESUMO

Here we present the anion binding and anion transport properties of a series of calix[6]arenes decorated on their small rim with either halogen bond or hydrogen bond donating groups. We show that the halogen bond donating iodotriazole groups enable highly selective transport of chloride and nitrate anions, without transport of protons or hydroxide, at rates similar to those observed with thiourea or squaramide groups.


Assuntos
Calixarenos , Halogênios , Ânions/química , Calixarenos/química , Cloretos , Halogênios/química , Ligação de Hidrogênio , Transporte de Íons
9.
Life (Basel) ; 12(3)2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35330109

RESUMO

Studying energy deposition by space radiation at the cellular scale provides insights on health risks to astronauts. Using the Monte Carlo track structure code RITRACKS, and the chromosome aberrations code RITCARD, we performed a modeling study of single-ion energy deposition spectra and chromosome aberrations for high-energy (>250 MeV/n) ion beams with linear energy transfer (LET) varying from 0.22 to 149.2 keV/µm. The calculations were performed using cells irradiated directly by mono-energetic ion beams, and by poly-energetic beams after particle transport in a digital mouse model, representing the radiation exposure of a cell in a tissue. To discriminate events from ion tracks directly traversing the nucleus, to events from δ-electrons emitted by distant ion tracks, we categorized ion contributions to microdosimetry or chromosome aberrations into direct and indirect contributions, respectively. The ions were either ions of the mono-energetic beam or secondary ions created in the digital mouse due to interaction of the beam with tissues. For microdosimetry, the indirect contribution is largely independent of the beam LET and minimally impacted by the beam interactions in mice. In contrast, the direct contribution is strongly dependent on the beam LET and shows increased probabilities of having low and high-energy deposition events when considering beam transport. Regarding chromosome aberrations, the indirect contribution induces a small number of simple exchanges, and a negligible number of complex exchanges. The direct contribution is responsible for most simple and complex exchanges. The complex exchanges are significantly increased for some low-LET ion beams when considering beam transport.

10.
Zookeys ; 1086: 84-135, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35221746

RESUMO

Because of their ability for aerial dispersal using silk and preference for open habitats, many wolf spiders are formidable colonisers. Pioneering arachnologists were already aware of the large and colourful wolf spiders in the Madeira archipelago, currently included in the genus Hogna Simon, 1885. The origins were investigated and species boundaries of Madeiran Hogna examined by integrating target-gene and morphological information. A multi-locus phylogenetic analysis of a thorough sampling across wolf-spider diversity suggested a single origin of Madeiran endemics, albeit with low support. Divergence time estimation traced back their origin to the late Miocene, a time of major global cooling that drove the expansion of grasslands and the associated fauna. Morphological examination of types and newly collected material revealed a new species, hereby described as H.isambertoi Crespo, sp. nov. Additionally, H.blackwalli is revalidated and three new synonymies are proposed, namely H.biscoitoi Wunderlich, 1992, junior synonym of H.insularum Kulczynski, 1899, H.schmitzi Wunderlich, 1992, junior synonym of H.maderiana (Walckenaer, 1837), and Arctosamaderana Roewer, 1960 junior synonym of H.ferox (Lucas, 1838). Species delimitation analyses of mitochondrial and nuclear markers provided additional support for morphological delineations. The species pair H.insularum and H.maderiana, however, constituted an exception: the lack of exclusive haplotypes in the examined markers, along with the discovery of intermediate forms, pointed to hybridisation between these two species as reported in other congeneric species on islands. Finally, the conservation status of the species is discussed and candidates for immediate conservation efforts are identified.

11.
Rev. esp. geriatr. gerontol. (Ed. impr.) ; 57(1): 13-19, ene.-feb. 2022. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-205479

RESUMO

Objetivo: Conocer la priorización por personas ≥ 70 años de una serie de componentes habituales en la valoración geriátrica integral (VGI) realizada en Atención Primaria (AP), según su percepción de la influencia en la salud.Método: Estudio transversal en AP mediante cuestionario a 109 personas, excluyendo a pacientes al final de la vida, o con alteración cognitiva, sensorial o psiquiátrica que dificultase su participación.La variable principal fue una selección de 23 ítems del área físico/clínica, funcional, mental y sociofamiliar, habituales en una VGI en AP. Otras: edad, sexo, cuestionario VIDA de actividades instrumentales de la vida diaria, número de medicamentos, índice de comorbilidad de Charlson.Resultados: Mediana de edad 78 años, percentil 75 de 84; 64,2% mujeres. Cuatro personas (3,7%) tenían alterado el cuestionario VIDA (< 32 puntos). Mediana de 5 medicamentos habituales y 98 (90%) sin comorbilidad relevante según el Charlson. Sin diferencias estadísticamente significativas al contrastar sexo con edad, resultado del VIDA y número de medicamentos.Los ítems mejor valorados según estadísticos de centralización fueron fumar y la memoria, y considerando la mejor puntuación (4-5 sobre 5): medicación adecuada (93,6% de los encuestados, IC del 95%, 87,3-96,8), condiciones de boca/dentadura (92,7%, IC del 95%, 86,2-96,2), estado de ánimo (91,7%, IC del 95%, 85,1-95,6), capacidad para realizar AVD (91,7%, IC del 95%, 85,1-95,6).Conclusiones: Los pacientes consideraban fumar, la memoria, la medicación adecuada, el estado de boca/dentadura y de ánimo, y las AVD como más influyentes en la salud. Ante la importancia de la participación de los pacientes en el contenido de la VGI y la escasez de estos trabajos, se hacen pertinentes nuevos estudios que profundicen este tema. (AU)


Objective: To know the prioritization by people aged ≥70 of a series of common components in the comprehensive geriatric assessment (CGA) in primary care (PC), according to the influence on health.Method: Cross-sectional descriptive study through questionnaire to 109 people, have been excluded those at the end of life or with cognitive, sensory or mental/psychiatric impairment that made collaboration difficult.The main variable was a selection of 23 items of the physical/clinical, functional, mental and social/family, common components on a CGA in PC. Others: age, sex, VIDA questionnaire of instrumental activities of daily living (IADL), number of medications, and Charlson comorbidity index.Results: Median age 78 years, 75 percentile of 84; 64.2% women. Four people (3.7%) had altered VIDA questionnaire (<32 points). Median of 5 chronic medications, and 98 (90%) comorbidity absence considering Charlson index. Without statistically significant differences contrasting gender with age, result in VIDA, nor number of chronic medications.The best scored items according to centralization statistics were smoking and memory, and considering the best score (4–5 out of 5) of the Likert scale: proper medication (93.6% of the people surveyed, 95% CI: 87.3–96.8), mouth/teeth condition (92.7%, 95% CI: 86.2–96.2), mood (91.7%, 95% CI: 85.1–95.6), and capacity for ADL (91.7%, 95% CI:85.1–95.6).Conclusions: Smoking, memory, proper medication, mouth/teeth condition, mood and ADL were considered as the most influential in health by patients. Because of the important of patient participation in the content of the CGA and the scarcity of these kind of studies, new studies that deepen this issue become relevant. (AU)


Assuntos
Humanos , Idoso , Idoso de 80 Anos ou mais , Atenção Primária à Saúde , Geriatria , Serviços de Saúde para Idosos , Atividades Cotidianas
12.
Rev Esp Geriatr Gerontol ; 57(1): 13-19, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-34330542

RESUMO

OBJECTIVE: To know the prioritization by people aged ≥70 of a series of common components in the comprehensive geriatric assessment (CGA) in primary care (PC), according to the influence on health. METHOD: Cross-sectional descriptive study through questionnaire to 109 people, have been excluded those at the end of life or with cognitive, sensory or mental/psychiatric impairment that made collaboration difficult. The main variable was a selection of 23 items of the physical/clinical, functional, mental and social/family, common components on a CGA in PC. Others: age, sex, VIDA questionnaire of instrumental activities of daily living (IADL), number of medications, and Charlson comorbidity index. RESULTS: Median age 78 years, 75 percentile of 84; 64.2% women. Four people (3.7%) had altered VIDA questionnaire (<32 points). Median of 5 chronic medications, and 98 (90%) comorbidity absence considering Charlson index. Without statistically significant differences contrasting gender with age, result in VIDA, nor number of chronic medications. The best scored items according to centralization statistics were smoking and memory, and considering the best score (4-5 out of 5) of the Likert scale: proper medication (93.6% of the people surveyed, 95% CI: 87.3-96.8), mouth/teeth condition (92.7%, 95% CI: 86.2-96.2), mood (91.7%, 95% CI: 85.1-95.6), and capacity for ADL (91.7%, 95% CI:85.1-95.6). CONCLUSIONS: Smoking, memory, proper medication, mouth/teeth condition, mood and ADL were considered as the most influential in health by patients. Because of the important of patient participation in the content of the CGA and the scarcity of these kind of studies, new studies that deepen this issue become relevant.


Assuntos
Atividades Cotidianas , Avaliação Geriátrica , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Atenção Primária à Saúde , Inquéritos e Questionários
13.
Biodivers Data J ; 10: e97682, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761525

RESUMO

Background: The Azores is a remote oceanic archipelago of nine islands which belongs to the Macaronesia biogeographical region hosting a unique biodiversity. The present Azorean landscape is strongly modified by the presence of man and only in small areas, where the soil or climate was too rough, have primitive conditions remained unchanged. Despite the fact that most of the Azorean native habitats are now lost, a large number of endemic species are still present and need urgent conservation. The present checklist of terrestrial and freshwater arthropods of the Azores Archipelago is based on all known published literature. The main goal of this work is to list, as rigorously as possible, all the known terrestrial and freshwater arthropods of the Azores. In this way, we are contributing to solve the 'Linnaean' shortfall, i.e. an incomplete taxonomic description of species-level diversity and the Wallacean Biodiversity Shortfall, the incomplete species distribution knowledge. New information: The checklist includes new records of arthropods at island and archipelago levels that were published in the last twelve years. Compared to the last checklist of Azorean arthropods (Borges et al. 2010b), a total of 217 taxa (species and subspecies) are added.Currently, the total number of terrestrial and freshwater arthropod species and subspecies in the Azores is estimated to be 2420 taxa belonging to 14 classes, 53 orders, 440 families, 1556 genera, 2400 species and 149 individual subspecies.The most diverse orders of Azorean arthropods are: Coleoptera (585 taxa), Diptera (423 taxa), Hemiptera (338 taxa), Hymenoptera (163 taxa), Lepidoptera (159 taxa) and Araneae (133 taxa).A total of 276 endemic taxa are currently known (232 species and 44 subspecies), belonging to eight classes and 22 orders. São Miguel, Terceira and Pico are the islands with higher number of endemic species and subspecies. In the Azores, the number of native non-endemic taxa is 793 taxa, totalling 1069 indigenous taxa. Compared to the other nearest Macaronesian archipelagos (Madeira and Canaries), the Azorean arthropod fauna is characterised by a lower percentage of endemism (endemics/indigenous: 26% in Azores, 47% in Madeira Archipelago and 42% in Canary Islands) and a high proportion of exotic introduced taxa (39% in Azores, 19% in Madeira Archipelago and 8% in Canary Islands).Based on recent IUCN Red-listing of Azorean arthropods, a large fraction of the endemic taxa is under high threat.

14.
Org Biomol Chem ; 19(38): 8324-8337, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34523662

RESUMO

Synthetic anion transporters can be developed using anion receptors that are able to bind the anion and stabilize it in the lipophilic interior of a bilayer membrane, and they usually contain functional groups with acidic NHs, such as ureas, thioureas and squaramides. To assess the suitability of acylhydrazones as a new functional group for the preparation of anion transporters, we have studied a family of thioureas functionalized with these and related functional groups. 1H NMR titrations and DFT calculations indicate that the thioureas bearing acylhydrazone groups behave as chloride receptors with two separate binding sites, of which the acylhydrazone binds weaker than the thiourea. Chloride transport studies show that the additional binding site has a detrimental effect on thiourea-based transporters, and this phenomenon is also observed for bis(thio)ureas with two separate binding sites. We propose that the presence of a second anion binding unit hinders the transport activity of the thiourea due to additional interactions with the phospholipids of the membrane. In agreement with this hypothesis, extensive molecular dynamics simulations suggest that the molecules will tend to be positioned in the water/lipid interface, driven by the interaction of the NHs of the thiourea and of the acylhydrazone groups with the POPC polar head groups and water molecules. Moreover, the interaction energies show that the poorest transporters have indeed the strongest interactions with the membrane phospholipids, inhibiting chloride transport. This detrimental effect of additional functional groups on transport activity should be considered when designing new ion transporters, unless these groups cooperatively promote anion recognition and transmembrane transport.

15.
Rev. cuba. med ; 60(2): e1510, tab, graf
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1280345

RESUMO

Introducción: La desensibilización rápida a medicamentos induce una tolerancia temporal a los quimioterapéuticos que provocan reacciones de hipersensibilidad. Objetivo: Evaluar el protocolo de desensibilización rápida en escenario ambulatorio en pacientes que presentaron reacciones de hipersensibilidad a fármacos citotóxicos. Métodos: Se realizó un estudio observacional, y retrospectivo, de 30 pacientes con cáncer que desarrollaron reacciones de hipersensibilidad entre los años 2016 y 2018, tratados en el Hospital de Día del Servicio de Oncología del Clínico Quirúrgico Hermanos Ameijeiras. Se clasificaron según su intensidad, y se analizaron variables demográficas, características clínicas, y síntomas presentados. Se utilizó un protocolo en doce etapas basado en tres diluciones del fármaco. Se administró premedicación en todos los casos. Se realizó estadística descriptiva, y para la asociación entre variables, se utilizó la prueba estadística Chi-cuadrado. Resultados: La mediana de edad fue 54 años (23;77). Predominaron las mujeres; los menores de 60 años; tumor primario de colon; antecedentes de alergia; el oxaliplatino como fármaco más implicado; las RHS durante la infusión; e intensidad moderada. Fueron más frecuentes los síntomas cutáneos y gastrointestinales. Con la aplicación del protocolo se completó la quimioterapia planificada a los 30 pacientes (145 ciclos adicionales). Solo se presentaron ocho desensibilizaciones con reacciones leves de tipo cutáneas. El 94,5 por ciento de las desensibilizaciones no presentaron reacción alguna. Conclusiones: Constituye el primer reporte nacional de la utilización exitosa de un protocolo de desensibilización rápida a citostáticos que demostró ser eficaz y seguro en el escenario ambulatorio, con un manejo multidisciplinario(AU)


Introduction: Rapid desensitization to drugs induces a temporary tolerance to chemotherapeutics causing hypersensitivity reactions. Objective: To evaluate the rapid desensitization protocol in an outpatient setting in patients who had hypersensitivity reactions to cytotoxic drugs. Methods: An observational and retrospective study was carried out in 30 cancer patients, who developed hypersensitivity reactions, from 2016 to 2018. They were treated in the outpatient Oncology service at Hermanos Ameijeiras Surgical Clinical Hospital. These subjects were classified according to intensity; demographic variables, clinical characteristics, and symptoms were analyzed. A twelve-step protocol based on three dilutions of the drug was used. Premedication was administered in all cases. Descriptive statistics and for the association between variables were performed. Chi-square statistical test was used. Results: The median age was 54 years (23; 77). Predominance was observed in women, those under 60 years of age, primary colon tumor, history of allergy, oxaliplatin as the drug most implicated, HRH during infusion, and moderate intensity. Skin and gastrointestinal symptoms were more frequent. The planned chemotherapy was completed with the application of the protocol, in all 30 patients (145 additional cycles). There were only eight desensitization with mild skin-type reactions. 94.5 percent of desensitizations did not show any reaction. Conclusions: It constitutes the first national report of successful use of a rapid desensitization protocol to cytostatics that proved to be effective and safe in the outpatient setting with multidisciplinary management(AU)


Assuntos
Humanos , Feminino , Dessensibilização Imunológica , Oxaliplatina/uso terapêutico , Hipersensibilidade , Antineoplásicos/uso terapêutico , Epidemiologia Descritiva , Estudos Retrospectivos , Estudo Observacional
16.
Chemistry ; 27(26): 7320, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33956385

RESUMO

Invited for the cover of this issue are Dr. Stephen Butler, Dr. Hennie Valkenier and co-workers at Université Libre de Bruxelles, Loughborough University, Masaryk University, and the University of Bristol. The image depicts the transport of bicarbonate anions versus the spontaneous diffusion of CO2 across the lipid bilayer of a liposome. Read the full text of the article at 10.1002/chem.202100491.

17.
Chemistry ; 27(26): 7367-7375, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33932059

RESUMO

Anion receptors can be used to transport ions across lipid bilayers, which has potential for therapeutic applications. Synthetic bicarbonate transporters are of particular interest, as defects in transmembrane transport of bicarbonate are associated with various diseases. However, no convenient method exists to directly observe bicarbonate transport and study the mechanisms involved. Here, an assay is presented that allows the kinetics of bicarbonate transport into liposomes to be monitored directly and with great sensitivity. The assay utilises an encapsulated europium(III) complex, which exhibits a large increase in emission intensity upon binding bicarbonate. Mechanisms involving CO2 diffusion and the dissipation of a pH gradient are shown to be able to lead to an increase in bicarbonate concentration within liposomes, without transport of the anion occurring at all. By distinguishing these alternative mechanisms from actual bicarbonate transport, this assay will inform the future development of bicarbonate transporters.


Assuntos
Bicarbonatos , Bicamadas Lipídicas , Transporte Biológico , Concentração de Íons de Hidrogênio , Transporte de Íons , Cinética
18.
Chem Commun (Camb) ; 57(22): 2736-2739, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33629090

RESUMO

Herein we report the design, synthesis and assessment of the first example of a squaramide-based self-immolative system triggered by an enzymatic reduction. We have proved that the release of the alkylating agent N',N'-(bis(2-chloroethyl)benzene)-1,4-diamine (ANM) provokes a dramatic reduction of the survival factor in glioblastoma cells, evidencing the suitability of the squaramide-based spacer for drug delivery applications.


Assuntos
Preparações de Ação Retardada , Quinina/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Cinética , Estrutura Molecular , Quinina/química , Análise Espectral/métodos
19.
Front Cell Infect Microbiol ; 11: 792584, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35096645

RESUMO

COVID-19 is the most consequential pandemic of the 21st century. Since the earliest stage of the 2019-2020 epidemic, animal models have been useful in understanding the etiopathogenesis of SARS-CoV-2 infection and rapid development of vaccines/drugs to prevent, treat or eradicate SARS-CoV-2 infection. Early SARS-CoV-1 research using immortalized in-vitro cell lines have aided in understanding different cells and receptors needed for SARS-CoV-2 infection and, due to their ability to be easily manipulated, continue to broaden our understanding of COVID-19 disease in in-vivo models. The scientific community determined animal models as the most useful models which could demonstrate viral infection, replication, transmission, and spectrum of illness as seen in human populations. Until now, there have not been well-described animal models of SARS-CoV-2 infection although transgenic mouse models (i.e. mice with humanized ACE2 receptors with humanized receptors) have been proposed. Additionally, there are only limited facilities (Biosafety level 3 laboratories) available to contribute research to aid in eventually exterminating SARS-CoV-2 infection around the world. This review summarizes the most successful animal models of SARS-CoV-2 infection including studies in Non-Human Primates (NHPs) which were found to be susceptible to infection and transmitted the virus similarly to humans (e.g., Rhesus macaques, Cynomolgus, and African Green Monkeys), and animal models that do not require Biosafety level 3 laboratories (e.g., Mouse Hepatitis Virus models of COVID-19, Ferret model, Syrian Hamster model). Balancing safety, mimicking human COVID-19 and robustness of the animal model, the Murine Hepatitis Virus-1 Murine model currently represents the most optimal model for SARS-CoV-2/COVID19 research. Exploring future animal models will aid researchers/scientists in discovering the mechanisms of SARS-CoV-2 infection and in identifying therapies to prevent or treat COVID-19.


Assuntos
COVID-19 , Animais , Chlorocebus aethiops , Cricetinae , Modelos Animais de Doenças , Furões , Humanos , Macaca mulatta , Camundongos , SARS-CoV-2
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