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1.
Dalton Trans ; 53(25): 10637-10643, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38860297

RESUMEN

The preparation of Fe(II) complexes combining monodentate NCX- (X = S or Se) and the tetradentate Schiff base chiral ligands RR-L1 and SS-L1 = (RR- or SS-L1 = 1R,2R or 1S,2S)-N1,N2-bis(pyridin-2-ylmethylen)cyclohexane-1,2-diamine in acetone results in an unexpected reaction. Thus, four enantiomerically pure compounds of formulas [Fe(RR-S-L2)(NCX)2] and [Fe(SS-R-L2)(NCX)2] (X = S or Se) are formed by the new asymmetrical ligand L2. In L2, one acetone solvent molecule is incorporated into the ligand forming a bond with the C atom of one of the two CN imine groups of L1, which is transformed into an amine (Mannich reaction). This reaction is diastereoselective as the incorporation of acetone leads to an asymmetric C adjacent to the NH group with opposite chirality S- or R- to that of the cyclohexane carbons (RR- or SS-, respectively). Therefore, L2 contains three C chiral centers. Structural and magnetic characterization of these compounds demonstrates that they show in the bulk a gradual spin-crossover behavior and LIESST effect. Interestingly, the presence of an intramolecular hydrogen bond between the integrated acetone molecule and the NH group can trigger a secondary stimuli-responsive behavior in the system. Therefore, by changing the solvent polarity, the color of the complex in solution can be easily tuned.

2.
NPJ Syst Biol Appl ; 9(1): 54, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37903760

RESUMEN

In systems biology, mathematical models and simulations play a crucial role in understanding complex biological systems. Different modelling frameworks are employed depending on the nature and scales of the system under study. For instance, signalling and regulatory networks can be simulated using Boolean modelling, whereas multicellular systems can be studied using agent-based modelling. Herein, we present PhysiBoSS 2.0, a hybrid agent-based modelling framework that allows simulating signalling and regulatory networks within individual cell agents. PhysiBoSS 2.0 is a redesign and reimplementation of PhysiBoSS 1.0 and was conceived as an add-on that expands the PhysiCell functionalities by enabling the simulation of intracellular cell signalling using MaBoSS while keeping a decoupled, maintainable and model-agnostic design. PhysiBoSS 2.0 also expands the set of functionalities offered to the users, including custom models and cell specifications, mechanistic submodels of substrate internalisation and detailed control over simulation parameters. Together with PhysiBoSS 2.0, we introduce PCTK, a Python package developed for handling and processing simulation outputs, and generating summary plots and 3D renders. PhysiBoSS 2.0 allows studying the interplay between the microenvironment, the signalling pathways that control cellular processes and population dynamics, suitable for modelling cancer. We show different approaches for integrating Boolean networks into multi-scale simulations using strategies to study the drug effects and synergies in models of cancer cell lines and validate them using experimental data. PhysiBoSS 2.0 is open-source and publicly available on GitHub with several repositories of accompanying interoperable tools.


Asunto(s)
Modelos Biológicos , Neoplasias , Humanos , Simulación por Computador , Transducción de Señal , Modelos Teóricos , Análisis de Sistemas , Microambiente Tumoral
3.
Data Brief ; 50: 109512, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37691739

RESUMEN

There is a growing body of knowledge on network intrusion detection, and several open data sets with network traffic and cyber-security threats have been released in the past decades. However, many data sets have aged, were not collected in a contemporary industrial communication system, or do not easily support research focusing on distributed anomaly detection. This paper presents the Westermo network traffic data set, 1.8 million network packets recorded in over 90 minutes in a network built up of twelve hardware devices. In addition to the raw data in PCAP format, the data set also contains pre-processed data in the form of network flows in CSV files. This data set can support the research community for topics such as intrusion detection, anomaly detection, misconfiguration detection, distributed or federated artificial intelligence, and attack classification. In particular, we aim to use the data set to continue work on resource-constrained distributed artificial intelligence in edge devices. The data set contains six types of events: harmless SSH, bad SSH, misconfigured IP address, duplicated IP address, port scan, and man in the middle attack.

4.
SAGE Open Med ; 11: 20503121231166647, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37123385

RESUMEN

Objective: Data on the frequency of cardiovascular disease in people living with human immunodeficiency virus from low- and middle-income countries is scarce. Methods: We performed an observational study based on data from a historical cohort of people living with human immunodeficiency virus in Colombia during a 10-year follow-up to describe the prevalence of cardiovascular risk factors and their behavior according to CD4 count. Results: One thousand patients were initially included, out of which 390 had a 10-year follow-up. The mean age was 34 (standard deviation 10) years, and 90% were male. We observed an increase in the prevalence of dyslipidemia (29%-52%, p < 0.001) and obesity (1.1%-3.5%, p < 0.001). Major cardiovascular events occurred in less than 1% of patients. Patients with a CD4 count <200 cells/mm3 had a higher frequency of acute myocardial infarction and obesity. Conclusion: Over time, people living with human immunodeficiency virus present with an increasing prevalence of cardiovascular risk factors, particularly those with a lower CD4 count.

5.
PhytoKeys ; 222: 19-26, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37252641

RESUMEN

Hoyamedusa M.D.De Leon, Cabactulan, Cuerdo & Rodda, sp. nov. (Apocynaceae, Asclepiadoideae) is described from the Philippines. Even though numerous taxa with a shrubby habit from this area are known, it can be immediately separated because of its urceolate corolla and prominent elongated corona lobes. No other species in the genus possesses such a combination of characters.

6.
bioRxiv ; 2023 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-37034764

RESUMEN

Ischemic stroke is a leading cause of death and disability, as therapeutic options for mitigating the long-term deficits precipitated by the event remain limited. Acute administration of the neuroendocrine modulator insulin-like growth factor-1 (IGF-1) attenuates ischemic stroke damage in preclinical models, and clinical studies suggest IGF-1 can reduce the risk of stroke and improve overall outcomes. The cellular mechanism by which IGF-1 exerts this protection is poorly defined, as all cells within the neurovascular unit express the IGF-1 receptor. We hypothesize that the functional regulation of both neurons and astrocytes by IGF-1 is critical in minimizing damage in ischemic stroke. To test this, we utilized inducible astrocyte-specific or neuron-specific transgenic mouse models to selectively reduce IGF-1R in the adult mouse brain prior to photothrombotic stroke. Acute changes in blood brain barrier permeability, microglial activation, systemic inflammation, and biochemical composition of the brain were assessed 3 hours following photothrombosis, and significant protection was observed in mice deficient in neuronal and astrocytic IGF-1R. When the extent of tissue damage and sensorimotor dysfunction was assessed for 3 days following stroke, only the neurological deficit score continued to show improvements, and the extent of improvement was enhanced with additional IGF-1 supplementation. Overall, results indicate that neuronal and astrocytic IGF-1 signaling influences stroke damage but IGF-1 signaling within these individual cell types is not required for minimizing tissue damage or behavioral outcome.

7.
Cryst Growth Des ; 23(4): 2730-2738, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37038402

RESUMEN

Three solvatomorphs of the iron(II) complex of 2,6-di[4-(ethylcarboxy)pyrazol-1-yl]pyridine (bpCOOEt2p) of formulas [Fe(bpCOOEt2p)2](ClO4)2·1.5MeNO2 (1), [Fe(bpCOOEt2p)2](ClO4)2·MeNO2 (2), and [Fe(bpCOOEt2p)2](ClO4)2·2MeNO2 (3) have been prepared and characterized. They show interesting spin-crossover (SCO) properties ranging from partial to complete thermal spin transitions and a light-induced excited spin-state trapping (LIESST) effect. In solvatomorph 2, a robust structure is formed with channels that enable the entrance or removal of solvent molecules by vapor diffusion without losing the crystallinity. Thus, solvent-exchanged samples [Fe(bpCOOEt2p)2](ClO4)2·MeNO2 (2·MeNO 2 ), [Fe(bpCOOEt2p)2](ClO4)2·MeCN (2·MeCN), [Fe(bpCOOEt2p)2](ClO4)2·0.5Me2CO (2·Me 2 CO), and [Fe(bpCOOEt2p)2](ClO4)2·MeCOOH (2·MeCOOH) were prepared by vapor diffusion of the solvents in a crystal of the compound previously heated to 400 K in a single-crystal to single-crystal (SCSC) fashion. Interestingly, this causes a change of spin state with a stabilization of the low-spin state in 2·Me 2 CO and the high-spin state in 2·MeCN. Therefore, the SCO properties of 2 can be tuned in a reversible way by exposure to different solvents.

8.
Chem Sci ; 14(11): 3048-3055, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36937587

RESUMEN

A bifunctionalized polyoxometalate (POM), [V6O19(C16H15N6O)2]2-, which contains a redox active hexavanadate moiety covalently linked to two tridentate 2,6-bis(pyrazol-1-yl)pyridine (1-bpp) ligands, has been prepared and characterized. Reaction of this hybrid molecule with Fe(ii) or Zn(ii) ions produces crystalline neutral 1D networks of formula Fe[V6O19(C16H15N6O)2]·solv (2) and Zn[V6O19(C16H15N6O)2]·solv (3) (solv = solvent molecules). Magnetic properties of 2 show an abrupt spin-crossover (SCO) with the temperature, which can be induced by light irradiation at 10 K (Light-Induced Excited Spin-State Trapping, LIESST effect). Interestingly, this porous and flexible structure enables reversible exchange of solvents in 2, which allows tuning the temperature of the thermal SCO. In 2 and 3, the hexavanadate unit can be reduced by electrochemical or chemical means in a reversible way. Chemical reduction and reoxidation by a postsynthetic method is accompanied by the insertion in the structure of the reductant and oxidant molecules (cobaltocene and tribromide, respectively), which provokes drastic changes in the spin state of Fe(ii). This leads to an elegant switching multifunctional material in which SCO properties of the Fe(ii) complexes coexist with the redox properties of the POM and can be tuned by a variety of stimuli such as temperature, light, solvent exchange or electron transfer. During the reduction process, 3 undergoes a single-crystal-to-single-crystal one-electron reduction, which confirms the presence of cobaltocenium cations by single crystal X-ray diffraction.

9.
Arch. cardiol. Méx ; 93(1): 26-29, ene.-mar. 2023. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1429701

RESUMEN

Abstract A 53-year-old male patient with history of repaired hernia, who is admitted for 5 days of progressive dyspnea with diagnosis of abdominal sepsis, a computed tomography angiography was made, revealing pulmonary embolism in bilateral main pulmonary artery, and cardiac thrombectomy was performed.


Resumen Paciente masculino de 53 años de edad con historial de reparación de hernia, quien fue ingresado por presentar 5 días de disnea progresiva con diagnóstico de sepsis abdominal, se le realizó una angiografía por tomografía computada, revelando embolismo bilateral arteria pulmonar principal, se realizó una trombectomía cardíaca.

10.
Arch Cardiol Mex ; 93(1): 26-29, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36757786

RESUMEN

A 53-year-old male patient with history of repaired hernia, who is admitted for 5 days of progressive dyspnea with diagnosis of abdominal sepsis, a computed tomography angiography was made, revealing pulmonary embolism in bilateral main pulmonary artery, and cardiac thrombectomy was performed.


Paciente masculino de 53 años de edad con historial de reparación de hernia, quien fue ingresado por presentar 5 días de disnea progresiva con diagnóstico de sepsis abdominal, se le realizó una angiografía por tomografía computada, revelando embolismo bilateral arteria pulmonar principal, se realizó una trombectomía cardíaca.


Asunto(s)
Embolia Paradójica , Foramen Oval Permeable , Embolia Pulmonar , Trombosis , Masculino , Humanos , Persona de Mediana Edad , Trombosis/cirugía , Choque Cardiogénico/etiología , Embolia Paradójica/diagnóstico , Embolia Paradójica/cirugía , Trombectomía/métodos , Embolia Pulmonar/complicaciones , Embolia Pulmonar/cirugía
11.
Front Immunol ; 14: 1282859, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38414974

RESUMEN

Introduction: The COVID-19 Disease Map project is a large-scale community effort uniting 277 scientists from 130 Institutions around the globe. We use high-quality, mechanistic content describing SARS-CoV-2-host interactions and develop interoperable bioinformatic pipelines for novel target identification and drug repurposing. Methods: Extensive community work allowed an impressive step forward in building interfaces between Systems Biology tools and platforms. Our framework can link biomolecules from omics data analysis and computational modelling to dysregulated pathways in a cell-, tissue- or patient-specific manner. Drug repurposing using text mining and AI-assisted analysis identified potential drugs, chemicals and microRNAs that could target the identified key factors. Results: Results revealed drugs already tested for anti-COVID-19 efficacy, providing a mechanistic context for their mode of action, and drugs already in clinical trials for treating other diseases, never tested against COVID-19. Discussion: The key advance is that the proposed framework is versatile and expandable, offering a significant upgrade in the arsenal for virus-host interactions and other complex pathologies.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Reposicionamiento de Medicamentos , Biología de Sistemas , Simulación por Computador
12.
Chem Sci ; 13(25): 7419-7428, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35872828

RESUMEN

By combining 3,6-N-ditriazolyl-2,5-dihydroxy-1,4-benzoquinone (H2trz2An) with NIR-emitting ErIII ions, two different 3D neutral polymorphic frameworks (1a and 1b), differing in the number of uncoordinated water molecules, formulated as [Er2(trz2An)3(H2O)4] n ·xH2O (x = 10, a; x = 7, b), have been obtained. The structure of 1a shows layers with (6,3) topology forming six-membered rings with distorted hexagonal cavities along the bc plane. These 2D layers are interconnected through the N4 atoms of the two pendant arms of the trz2An linkers, leading to a 3D framework, where neighboring layers are eclipsed along the a axis, with hexagonal channels filled with water molecules. In 1b, layers with (6,3) topology in the [101] plane are present, each ErIII ion being connected to three other ErIII ions through bis-bidentate trz2An linkers, forming rectangular six-membered cavities. 1a and 1b are multifunctional materials showing coexistence of NIR emission and field-induced slow relaxation of the magnetization. Remarkably, 1a is a flexible MOF, showing a reversible structural phase transition involving shrinkage/expansion from a distorted hexagonal 2D framework to a distorted 3,6-brickwall rectangular 3D structure in [Er2(trz2An)3(H2O)2] n ·2H2O (1a_des). This transition is triggered by a dehydration/hydration process under mild conditions (vacuum/heating to 360 K). The partially dehydrated compound shows a sizeable change in the emission properties and an improvement of the magnetic blocking temperature with respect to the hydrated compound, mainly related to the loss of one water coordination molecule. Theoretical calculations support the experimental findings, indicating that the slight improvement observed in the magnetic properties has its origin in the change of the ligand field around the ErIII ion due to the loss of a water molecule.

13.
Sci Rep ; 12(1): 9132, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35672332

RESUMEN

The world has gone through unprecedented changes since the global pandemic hit. During the early phase of the pandemic, the absence of known drugs or pharmaceutical treatments forced governments to introduce different policies in order to help reduce contagion rates and manage the economic consequences of the pandemic. This paper analyses the causal impact on mobility and COVID19 incidence from policy makers in Cataluña, Spain. We use anonymized phone-based mobility data together with reported incidence and apply a series of causal impact models frequently used in econometrics and policy evaluation in order to measure the policies impact. We analyse the case of Cataluña and the public policy decision of closing all bars and restaurants down for a 5 week period between 2020-16-10 and 2020-23-11. We find that this decision led to a significant reduction in mobility. It not only led to reductions in mobility but from a behavioural economics standpoint, we highlight how people responded to the policy decision. Moreover, the policy of closing bars and restaurants slowed the incidence rate of COVID19 after a time lag has been taken into account. These findings are significant since governments worldwide want to restrict movements of people in order to slow down COVID19 incidence without infringing on their rights directly.


Asunto(s)
COVID-19 , COVID-19/epidemiología , COVID-19/prevención & control , Humanos , Incidencia , Pandemias/prevención & control , Política Pública , Restaurantes
14.
Travel Med Infect Dis ; 49: 102361, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35640809

RESUMEN

INTRODUCTION: SARS-CoV-2 continues to have a high rate of contagion worldwide. The new variant of concern, Omicron, has mutations that decrease the effectiveness of vaccines and evade antibodies from previous infections resulting in a fourth wave of the pandemic. It was identified in Mexico in December 2021. METHODS: The Traveler's Preventive Care Clinic from the Faculty of Medicine UNAM at Mexico City International Airport has performed rapid antigen and PCR SARS CoV2 tests since January 2021 to comply with the new travel requirements. Demographic and clinical characteristics were collected from each passenger and the fourth wave of the pandemic in Mexico mainly caused by Omicron was analyzed in the travelers. RESULTS: A total of 5176 travelers attended the clinic between the second half of December 2021 and January 2022. Ten percent of all the tests performed were positive (13% of PCR and 9.3% of antigens, p = 0.001). Most of the SARS CoV2 positive cases were asymptomatic (78%), with a ratio of 3.5:1 over the symptomatic. By age groups, this ratio was higher for those under 20 years old (8.7:1). DISCUSSION: This study shows the rapid escalation of positivity that occurred in Mexico, detected in travelers, from the second half of December 2020 and throughout the month of January 2021. The incidence of COVID-19 was extremely high in travelers who were mostly asymptomatic for the period under study.


Asunto(s)
COVID-19 , Adulto , Aeropuertos , COVID-19/epidemiología , Humanos , México/epidemiología , Prevalencia , SARS-CoV-2 , Adulto Joven
15.
Front Mol Biosci ; 9: 836794, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35463947

RESUMEN

The emergence of cell resistance in cancer treatment is a complex phenomenon that emerges from the interplay of processes that occur at different scales. For instance, molecular mechanisms and population-level dynamics such as competition and cell-cell variability have been described as playing a key role in the emergence and evolution of cell resistances. Multi-scale models are a useful tool for studying biology at very different times and spatial scales, as they can integrate different processes occurring at the molecular, cellular, and intercellular levels. In the present work, we use an extended hybrid multi-scale model of 3T3 fibroblast spheroid to perform a deep exploration of the parameter space of effective treatment strategies based on TNF pulses. To explore the parameter space of effective treatments in different scenarios and conditions, we have developed an HPC-optimized model exploration workflow based on EMEWS. We first studied the effect of the cells' spatial distribution in the values of the treatment parameters by optimizing the supply strategies in 2D monolayers and 3D spheroids of different sizes. We later study the robustness of the effective treatments when heterogeneous populations of cells are considered. We found that our model exploration workflow can find effective treatments in all the studied conditions. Our results show that cells' spatial geometry and population variability should be considered when optimizing treatment strategies in order to find robust parameter sets.

16.
Arch Cardiol Mex ; 2022 Apr 04.
Artículo en Español | MEDLINE | ID: mdl-35377577

RESUMEN

Background: The cardiovascular sequelae by the SARS-COV-2 infection is prevalent in a significant portion of the recovered patients from the acute presentation of the SARS-COV-2. Actually, the clinic cardiac control of the post-acute COVID syndrome has been working out without a well-established protocol, making the appropriate diagnosis of the cardiac diseases produced by the different damage mechanisms from COVID-19. Objectives: Standardize cardiovascular care and the follow up of COVID-19 survivors in the function on disease severity and identify patients who develop SPC-19A for timely care. Materials and methods: Through an extensive bibliographic review, this article has the purpose of provide the necessary information to make possible the early diagnosis and following of the cardiac complications that has been recorded trough the months after the acute disease from COVID-19.


Antecedentes: Las secuelas cardiovasculares ocasionadas por la enfermedad por coronavirus 2019 (COVID-19) son frecuentes en una importante proporción de los pacientes recuperados del cuadro agudo de la enfermedad. Hasta el día de hoy el seguimiento cardiológico del síndrome agudo post-COVID-19 (SPC-19A) se ha realizado de forma heterogénea y sin directrices que permitan al clínico identificar oportunamente los cambios que preceden a enfermedades cardiológicas derivadas de los distintos mecanismos de daño inducidos por COVID-19. Objetivos: Estandarizar la atención y seguimiento cardiovascular de los supervivientes de COVID-19 en función de la gravedad de la enfermedad e identificar a los pacientes que desarrollen SPC-19A para su atención oportuna. Material y métodos: Mediante una revisión extensa de bibliografía, este documento tiene la intención de unificar y proporcionar la información necesaria para diagnosticar y dar seguimiento a las complicaciones cardiacas que se han documentado en los meses posteriores a la resolución de la COVID-19 aguda.

17.
Rev. colomb. ciencias quim. farm ; 51(1)ene.-abr. 2022.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1535820

RESUMEN

SUMMARY Introduction: Phthalocyanines are porphyrin-based dyes. They have plenty applications in different fields, including biomedical and chemical research. From a chemical point of view, Phthalocyanines are macrocyclictetraaza compounds, which mainly are made up of isoindol groups that confer aromaticity and planarity on Phthalocyanine structure. Unlike other kinds of porphyrin compounds, Phthalocyanine structure is able to chelate a lot of metals, which more often contribute to their huge variety of functions, including ROS generation, fluorescence, absorption spectra, and others. Aim: To evaluate phthalocyanines compounds owing their excellent photochemical and pharmaceutical properties that explain their wide use at the clinical and medical level. Methodology: We have carried out a meticulous search for scientific works related to the subject between April 2020 and April 2021, the most of them were written in English. As a result, we can say that, for studying Phthalocyanines' properties, the work can be separated into two issues: synthesis of the metalized phthalocyanines and photochemical and photobiological properties. Results: Phthalocyanines have plenty properties that are desirable to biomedical and pharmaceutical research. Because of their photochemical and photobiological properties, as well as ROS generation, Phthalocyanines are one of the photosenstitizers most widely used in photodynamic therapy. They also have antibacterial, antiviral and anticancer activities. In this sense, Phthalocyanine synthesis and in vitro studies are a very important scientific issue.


Introducción: las ftalocianinas son tintes porfirínicos. Tienen muchas aplicaciones en diferentes campos, incluida la investigación biomédica y química. Desde el punto de vista químico, las ftalocianinas son compuestos macrocíclicos de tetraaza. Se componen principalmente de grupos isoindol que confieren aromaticidad y planaridad a la estructura de la ftalocianina. Esta última es capaz de quelar muchos metales, que con mayor frecuencia contribuyen a su gran variedad de funciones, incluida la generación de EROS, la fluorescencia, los espectros de absorción y otros. Objetivo: evaluar algunos derivados de ftalocianinas gracias a las excelentes propiedades fotoquímicas y farmacéuticas que explican su amplio uso a nivel clínico y médico. Metodología: hemos realizado una búsqueda minuciosa de trabajos científicos relacionados con el tema entre abril de 2020 y abril de 2021, la mayoría de ellos escritos en inglés. Como resultado, podemos decir que, para estudiar las propiedades de las ftalocianinas, el trabajo se puede dividir en dos temas: síntesis de las ftalocianinas metalizadas y propiedades fotoquímicas y ffotobiológicas. Resultados: las ftalocianinas tienen muchas propiedades que son deseables para la investigación biomédica y farmacéutica. Por sus propiedades fotoquímicas y fotobiológicas, así como por la generación de EROS, las ftalocianinas son uno de los fotosensibilizadores más utilizados en terapia fotodinámica. También tienen actividades antibacterianas, antivirales y anticancerígenas. En este sentido, la síntesis de ftalocianina y los estudios in vitro son un tema científico muy importante.


Introdução: as ftalocianinas são corantes à base de porfirinas. Eles têm muitas aplicações em diferentes campos, incluindo pesquisas biomédicas e químicas. Do ponto de vista químico, as ftalocianinas são compostos macrocíclicos tetraaza, que são constituídos principalmente por grupos isoindol que conferem aromaticidade e planaridade à estrutura das ftalocianinas. Ao contrário de outros tipos de compostos de porfirina, a estrutura da ftalocianina é capaz de quelar uma grande quantidade de metais, que mais frequentemente contribuem para sua enorme variedade de funções, incluindo geração de ROS, fluorescência, espectro de absorção e outros. Objetivo: avaliar alguns derivados de ftalocianinas graças às excelentes propriedades fotoquímicas e farmacêuticas que explicam a sua ampla utilização a nível clínico e médico. Metodologia: efetuamos uma busca minuciosa de trabalhos científicos relacionados ao assunto entre abril de 2020 e abril de 2021, a maioria deles redigidos na língua inglesa. Como resultado, podemos dizer que, para estudar as propriedades das ftalocianinas, o trabalho pode ser dividido em duas questões: síntese das ftalocianinas metalizadas e propriedades fotoquímicas e fotobiológicas. Resultados: as ftalocianinas têm muitas propriedades desejáveis para a pesquisa biomédica e farmacêutica. Pelas suas propriedades fotoquímicas e fotobiológicas, além da geração de ROS, as ftalocianinas são um dos ffotossensibilizantes mais amplamente utilizados na terapia fotodinàmica e processos fototóxicos. Eles também têm atividades antibacteriana, antiviral e anticàncer. Nesse sentido, a síntese de ftalocianina e os estudos in vitro são uma questão científica muito importante.

18.
Sci Adv ; 8(9): eabl9155, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35235355

RESUMEN

Tropical cyclones drive coastal ecosystem dynamics, and their frequency, intensity, and spatial distribution are predicted to shift with climate change. Patterns of resistance and resilience were synthesized for 4138 ecosystem time series from n = 26 storms occurring between 1985 and 2018 in the Northern Hemisphere to predict how coastal ecosystems will respond to future disturbance regimes. Data were grouped by ecosystems (fresh water, salt water, terrestrial, and wetland) and response categories (biogeochemistry, hydrography, mobile biota, sedentary fauna, and vascular plants). We observed a repeated pattern of trade-offs between resistance and resilience across analyses. These patterns are likely the outcomes of evolutionary adaptation, they conform to disturbance theories, and they indicate that consistent rules may govern ecosystem susceptibility to tropical cyclones.

19.
Adv Mater ; 34(11): e2110027, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35032055

RESUMEN

Van der Waals heterostructures (vdWHs) provide the possibility of engineering new materials with emergent functionalities that are not accessible in another way. These heterostructures are formed by assembling layers of different materials used as building blocks. Beyond inorganic 2D crystals, layered molecular materials remain still rather unexplored, with only few examples regarding their isolation as atomically thin layers. Here, the family of van der Waals heterostructures is enlarged by introducing a molecular building block able to produce strain: the so-called spin-crossover (SCO). In these metal-organic materials, a spin transition can be induced by applying external stimuli like light, temperature, pressure, or an electric field. In particular, smart vdWHs are prepared in which the electronic and optical properties of the 2D material (graphene and WSe2 ) are clearly switched by the strain concomitant to the spin transition. These molecular/inorganic vdWHs represent the deterministic incorporation of bistable molecular layers with other 2D crystals of interest in the emergent fields of straintronics and band engineering in low-dimensional materials.

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