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1.
Faraday Discuss ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39290191

RESUMEN

We present for the first time a multiscale machine learning approach to jointly simulate atomic structure and dynamics with the corresponding solid state Nuclear Magnetic Resonance (ssNMR) observables. We study the use-case of spin-alignment echo (SAE) NMR for exploring Li-ion diffusion within the solid state electrolyte material Li3PS4 (LPS) by calculating quadrupolar frequencies of 7Li. SAE NMR probes long-range dynamics down to microsecond-timescale hopping processes. Therefore only a few machine learning force field schemes are able to capture the time- and length scales required for accurate comparison with experimental results. By using a new class of machine learning interatomic potentials, known as ultra-fast potentials (UFPs), we are able to efficiently access timescales beyond the microsecond regime. In tandem, we have developed a machine learning model for predicting the full 7Li electric field gradient (EFG) tensors in LPS. By combining the long timescale trajectories from the UFP with our model for 7Li EFG tensors, we are able to extract the autocorrelation function (ACF) for 7Li quadrupolar frequencies during Li diffusion. We extract the decay constants from the ACF for both crystalline ß-LPS and amorphous LPS, and find that the predicted Li hopping rates are on the same order of magnitude as those predicted from the Li dynamics. This demonstrates the potential for machine learning to finally make predictions on experimentally relevant timescales and temperatures, and opens a new avenue of NMR crystallography: using machine learning dynamical NMR simulations for accessing polycrystalline and glass ceramic materials.

2.
Faraday Discuss ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39291349

RESUMEN

We present a comprehensive study on the best practices for integrating first principles simulations in experimental quadrupolar solid-state nuclear magnetic resonance (SS-NMR), exploiting the synergies between theory and experiment for achieving the optimal interpretation of both. Most high performance materials (HPMs), such as battery electrodes, exhibit complex SS-NMR spectra due to dynamic effects or amorphous phases. NMR crystallography for such challenging materials requires reliable, accurate, efficient computational methods for calculating NMR observables from first principles for the transfer between theoretical material structure models and the interpretation of their experimental SS-NMR spectra. NMR-active nuclei within HPMs are routinely probed by their chemical shielding anisotropy (CSA). However, several nuclear isotopes of interest, e.g.7Li and 27Al, have a nuclear quadrupole and experience additional interactions with the surrounding electric field gradient (EFG). The quadrupolar interaction is a valuable source of information about atomistic structure, and in particular, local symmetry, complementing the CSA. As such, there is a range of different methods and codes to choose from for calculating EFGs, from all-electron to plane wave methods. We benchmark the accuracy of different simulation strategies for computing the EFG tensor of quadrupolar nuclei with plane wave density functional theory (DFT) and study the impact of the material structure as well as the details of the simulation strategy. Especially for small nuclei with few electrons, such as 7Li, we show that the choice of physical approximations and simulation parameters has a large effect on the transferability of the simulation results. To the best of our knowledge, we present the first comprehensive reference scale and literature survey for 7Li quadrupolar couplings. The results allow us to establish practical guidelines for developing the best simulation strategy for correlating DFT to experimental data extracting the maximum benefit and information from both, thereby advancing further research into HPMs.

3.
Clin Ter ; 175(Suppl 2(4)): 143-147, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39101413

RESUMEN

Background: Homicide by drowning in adults is rare. Usually, marks of violence are found on both the victim and the perpetrator, unless the victim was under the influence of alcohol, drugs, or was unexpectedly forced or dragged into the water. Indeed, many cases of drowning in adults are believed to be accidental, but they may be the result of drunken fights or attempts to make the death appear ac-cidental. In order to define the manner of death, cooperation between the forensic pathologist and the investigators is mandatory. Indeed, the autopsy is important to distinguish homicide by drowning from other kinds of drowning. The purpose of this study is to highlight the features of homicide by drowning. Materials and Methods: Literature search was conducted using PubMed databases, using the following keywords: "(homicide) and (drowning)". 3 articles were included in the systematic review, in addition to 3 cases observed in our institute. Conclusions: Both external examination and autopsy findings and the results of the investigation are essential to differentiate a homicide by drowning from accidental ones. The low specificity and variability of external and internal findings, the possibility of atypical asphyctic and nonasphyctic pathophysiological mechanisms, whose nature is not detectable at postmortem examinations, makes the diagnosis of cause of death difficult and often based on exclusion criteria only. In complex cases only using a strict forensic method allows to use the essential tools to identify the real manner of death.


Asunto(s)
Ahogamiento , Homicidio , Humanos , Homicidio/estadística & datos numéricos , Ahogamiento/mortalidad , Masculino , Adulto , Femenino , Persona de Mediana Edad , Autopsia
5.
Clin Ter ; 175(Suppl 1(4)): 10-15, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39054972

RESUMEN

Background: Investigating deaths related to chronic cocaine abuse can be a difficult task, particularly when they occur suddenly and without explanation. Cocaine abuse can trigger biological effects similar to physiological stressors, causing the body to produce heat-shock proteins (HSPs). However, there is still limited information on the specific levels of each HSP type. This systematic review aims to comprehensively collect and analyze all existing literature data regar-ding the relationship between HSPs and cocaine abuse to investigate whether HSPs can be utilized as forensic markers for accurately dia-gnosing cocaine-related deaths. Materials and Methods: The Authors conducted the literature search using PubMed and Scopus databases, searching for articles published between 1 January 1992 and 1 April 2024 using the text string: "heat shock protein" AND "cocaine". Conclusion: Twenty articles were collected, but only nine were included in the systematic review. The data gathered pertained to both human and murine species. The majority of the analyzed articles revealed an elevation in HSP25, HSP27, HSP60, HSP70, HSP72, and HSP73 levels in the brain, cerebellum, and liver, indicating cocaine-induced stress. The relationship between HSP and cocaine has been unclear over time. However, recent studies have shown that cocaine consumption leads to an increase in HSP levels, particularly in the central nervous system. This correlation can also be observed in certain types of liver cells that are capable of binding cocaine metabolites. In conclusion, HSP brain levels, along with other biomarkers, may be used to diagnose sudden, unexpected death related to cocaine abuse.


Asunto(s)
Trastornos Relacionados con Cocaína , Proteínas de Choque Térmico , Humanos , Trastornos Relacionados con Cocaína/complicaciones , Proteínas de Choque Térmico/metabolismo , Animales , Cocaína/efectos adversos , Ratones , Biomarcadores/metabolismo
6.
Clin Ter ; 175(Suppl 1(4)): 32-35, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39054977

RESUMEN

Background: Homicide by burning is rare, involving victims exposed to direct flames, often with accelerants. This demonstrates excessive force by the assaulter. A thorough investigation is vital as fire can conceal pathological findings. This study presents two emblematic cases of intentional burning. Case report: Two cases of homicide by fire are detailed. The first involves a male found dead in a fire-damaged apartment, doused with flammable liquid and set on fire by his partner. The autopsy showed heat hematoma and soot in the trachea and large bronchi. The second case involves a female set on fire with gasoline by an acquaintance, sustaining burns over 90% of her body and dying from hypovolemic shock. The autopsy revealed effusions in pleural and peritoneal cavities and a hyperaemic trachea. Conclusions: Intentional burnings are sporadic and difficult to classify without testimonial evidence. The difference between homicide and accidental burns relies on circumstantial evidence and antemortem injuries. Vital reactions to thermal lesions include red-base blisters, dilated capillaries, leukocyte infiltration, coagulative necrosis, heat hematoma, and soot in the airways. High carboxyhemoglobin levels indicate vitality. The first case showed heat hematoma and tracheal soot, while the second exhibited severe burns leading to hypovolemic shock. Testimonial evidence and crime scene examination were crucial in determining the homicidal nature. Forensic investigation of charred corpses requires a comprehensive evaluation of all available data. Crime scene analysis, combined with autopsy, toxicological tests, and post-mortem CT scans, helps establish the cause of death and differentiate between ante- and postmortem injuries.


Asunto(s)
Quemaduras , Incendios , Homicidio , Humanos , Masculino , Femenino , Quemaduras/etiología , Quemaduras/complicaciones , Adulto , Persona de Mediana Edad , Autopsia
7.
Clin Ter ; 175(Suppl 1(4)): 70-74, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39054986

RESUMEN

Background: The role of forensic pathologists is pivotal in definitively diagnosing drowning cases. Further differentiation becomes essential for distinguishing between freshwater drowning (FWD) and saltwater drowning (SWD). Aquaporins are small integral membrane proteins that serve as major water transport pathways in various cell types. AQP4 appears to be involved in mechanisms related to cerebral volume regulation. Our study aims to examine the expression of AQP4 in the brain as a potential marker for differentiating between FWD and SWD relating to autopsy-performing timing. Materials and Methods: A total of 23 cases were classified into three groups: FWD, SWD, and controls. All samples were classified upon autopsy-performing timing into two subgroups: within and after 72 hours of death. The samples were then processed for histological and immunohistochemical investigations. Conclusion: For autopsies performed within 72 hours of death, we found a significantly higher value of AQP4-positive astrocytes in cases of FWD compared to SWD and control groups. We also found a significantly lower AQP4 expression in SWD cases compared to the control group. For autopsies conducted after 72 hours, the immunohistochemical staining does not reveal the peripheral terminations of astrocytes, which appear blurred and only recognizable as halos. In conclusion, the data aligns with existing literature about autopsies performed within 72 hours. However, in autopsies conducted after 72 hours, uncertain and even opposed results are observed. The difference can be ascribed to the post-mortem transformative processes that take place upon the cessation of vital functions.


Asunto(s)
Acuaporina 4 , Autopsia , Ahogamiento , Inmunohistoquímica , Humanos , Acuaporina 4/análisis , Ahogamiento/diagnóstico , Masculino , Diagnóstico Diferencial , Femenino , Adulto , Persona de Mediana Edad , Factores de Tiempo , Agua Dulce , Anciano , Encéfalo/patología , Encéfalo/metabolismo , Adulto Joven , Agua de Mar , Adolescente , Astrocitos/metabolismo , Astrocitos/patología
8.
Biometals ; 37(5): 1237-1253, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38874822

RESUMEN

Candida species undeniably rank as the most prevalent opportunistic human fungal pathogens worldwide, with Candida albicans as the predominant representative. However, the emergence of non-albicans Candida species (NACs) has marked a significant shift, accompanied by rising incidence rates and concerning trends of antifungal resistance. The search for new strategies to combat antifungal-resistant Candida strains is of paramount importance. Recently, our research group reported the anti-Candida activity of a coordination compound containing copper(II) complexed with theophylline (theo) and 1,10-phenanthroline (phen), known as "CTP" - Cu(theo)2phen(H2O).5H2O. In the present work, we investigated the mechanisms of action of CTP against six medically relevant, antifungal-resistant NACs, including C. auris, C. glabrata, C. haemulonii, C. krusei, C. parapsilosis and C. tropicalis. CTP demonstrated significant efficacy in inhibiting mitochondrial dehydrogenases, leading to heightened intracellular reactive oxygen species production. CTP treatment resulted in substantial damage to the plasma membrane, as evidenced by the passive incorporation of propidium iodide, and induced DNA fragmentation as revealed by the TUNEL assay. Scanning electron microscopy images of post-CTP treatment NACs further illustrated profound alterations in the fungal surface morphology, including invaginations, cavitations and lysis. These surface modifications significantly impacted the ability of Candida cells to adhere to a polystyrene surface and to form robust biofilm structures. Moreover, CTP was effective in disassembling mature biofilms formed by these NACs. In conclusion, CTP represents a promising avenue for the development of novel antifungals with innovative mechanisms of action against clinically relevant NACs that are resistant to antifungals commonly used in clinical settings.


Asunto(s)
Antifúngicos , Candida , Complejos de Coordinación , Cobre , Farmacorresistencia Fúngica , Pruebas de Sensibilidad Microbiana , Fenantrolinas , Teofilina , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/síntesis química , Fenantrolinas/farmacología , Fenantrolinas/química , Candida/efectos de los fármacos , Cobre/química , Cobre/farmacología , Farmacorresistencia Fúngica/efectos de los fármacos , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Teofilina/farmacología , Teofilina/química , Especies Reactivas de Oxígeno/metabolismo , Humanos
9.
Commun Biol ; 7(1): 709, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38851856

RESUMEN

Vaccination reduces morbidity and mortality due to infections, but efficacy may be limited due to distinct immunogenicity at the extremes of age. This raises the possibility of employing adjuvants to enhance immunogenicity and protection. Early IFNγ production is a hallmark of effective vaccine immunogenicity in adults serving as a biomarker that may predict effective adjuvanticity. We utilized mass cytometry (CyTOF) to dissect the source of adjuvant-induced cytokine production in human blood mononuclear cells (BMCs) from newborns (~39-week-gestation), adults (~18-63 years old) and elders (>65 years of age) after stimulation with pattern recognition receptors agonist (PRRa) adjuvants. Dimensionality reduction analysis of CyTOF data mapped the BMC compartment, elucidated age-specific immune responses and profiled PRR-mediated activation of monocytes and DCs upon adjuvant stimulation. Furthermore, we demonstrated PRRa adjuvants mediated innate IFNγ induction and mapped NK cells as the key source of TLR7/8 agonist (TLR7/8a) specific innate IFNγ responses. Hierarchical clustering analysis revealed age and TLR7/8a-specific accumulation of innate IFNγ producing γδ T cells. Our study demonstrates the application of mass cytometry and cutting-edge computational approaches to characterize immune responses across immunologically distinct age groups and may inform identification of the bespoke adjuvantation systems tailored to enhance immunity in distinct vulnerable populations.


Asunto(s)
Adyuvantes Inmunológicos , Leucocitos Mononucleares , Humanos , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Adulto , Persona de Mediana Edad , Adyuvantes Inmunológicos/farmacología , Anciano , Adulto Joven , Adolescente , Interferón gamma/metabolismo , Recién Nacido , Femenino , Masculino , Factores de Edad , Inmunidad Innata
10.
Nat Commun ; 15(1): 5323, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38909053

RESUMEN

Bioethanol is a sustainable energy alternative and can contribute to global greenhouse-gas emission reductions by over 60%. Its industrial production faces various bottlenecks, including sub-optimal efficiency resulting from bacteria. Broad-spectrum removal of these contaminants results in negligible gains, suggesting that the process is shaped by ecological interactions within the microbial community. Here, we survey the microbiome across all process steps at two biorefineries, over three timepoints in a production season. Leveraging shotgun metagenomics and cultivation-based approaches, we identify beneficial bacteria and find improved outcome when yeast-to-bacteria ratios increase during fermentation. We provide a microbial gene catalogue which reveals bacteria-specific pathways associated with performance. We also show that Limosilactobacillus fermentum overgrowth lowers production, with one strain reducing yield by ~5% in laboratory fermentations, potentially due to its metabolite profile. Temperature is found to be a major driver for strain-level dynamics. Improved microbial management strategies could unlock environmental and economic gains in this US $ 60 billion industry enabling its wider adoption.


Asunto(s)
Bacterias , Etanol , Fermentación , Etanol/metabolismo , Bacterias/metabolismo , Bacterias/genética , Bacterias/clasificación , Microbiota/fisiología , Biocombustibles , Metagenómica , Microbiología Industrial/métodos , Temperatura
11.
Polymers (Basel) ; 16(5)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38475324

RESUMEN

In recent years, there has been a growing interest in developing smart drug delivery systems based on natural resources combined with stimulus-sensitive elements. This trend aims to formulate innovative and sustainable delivery platforms tailored for topical applications. This work proposed the use of layer-by-layer (LbL) methodology to fabricate biocompatible photo-responsive multilayer systems. These systems are composed of a polyoxometalate inorganic salt (POM) ([NaP5W30O110]14-) and a natural origin polymer, chitosan (CHT). Curcumin (CUR), a natural bioactive compound, was incorporated to enhance the functionality of these systems during the formation of hollow capsules. The capsules produced, with sizes between 2-5µm (SEM), were further dispersed into CHT/VCO (virgin coconut oil) emulsion solutions that were casted into molds and dried at 37 °C for 48 h. The system presented a higher water uptake in PBS than in acidic conditions, still significantly lower than that earlier reported to other CHT/VCO-based systems. The drug release profile is not significantly influenced by the medium pH reaching a maximum of 37% ± 1% after 48 h. The antioxidant performance of the designed structures was further studied, suggesting a synergistic beneficial effect resulting from CUR, POM, and VCO individual bioactivities. The increased amount of those excipients released to the media over time promoted an increase in the antioxidant activity of the system, reaching a maximum of 38.1% ± 0.1% after 48 h. This work represents a promising step towards developing advanced, sustainable drug delivery systems for topical applications.

12.
Front Oncol ; 14: 1308128, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38500657

RESUMEN

Background: Non-germinomatous germ cell tumors (NGGCT) accounts for one third of intracranial GCT. While the germinoma group have an excellent overall survival, the standard of practice for children with NGGCT is still under evaluation. Aims: Describe the results of the of the Brazilian consortium protocol. Methods: Since 2013, 15 patients with a diagnosis of NGGCT by histopathology and/or serum/cerebrospinal fluid (CSF) tumor markers, ßHCG >200mlU/ml and/or positive alpha-fetoprotein were treated with neoadjuvant chemotherapy with carboplatin, cyclophosphamide and etoposide followed by ventricular radiotherapy (RTV) of 18Gy with boost (32Gy) to the primary site. Metastatic patients underwent craniospinal irradiation (CSI) and "slow responders" to the four initial cycles of CT, to autologous stem cell transplantation (ASCT) followed by CSI. Results: Mean age, 13.1 years. Thirteen males. Primary sites: pineal (n=12), suprasellar (n=2) and bifocal (n=1). Four patients were metastatic at diagnosis. Eight patients had CSF and/or serum alpha-fetoprotein levels > 1,000ng/ml. Tumor responses after chemotherapy demonstrated complete in six cases and partial in seven, with "second-look" surgery being performed in five cases, and two patients presenting viable lesions being referred to ASCT. The main toxicity observed was hematological grades 3/4. Two patients with metastatic disease, one with Down Syndrome and AFP > 1,000ng/ml and the other with choriocarcinoma and pulmonary metastases, developed progressive disease resulting in death, as well as two other patients without evidence of disease, due to endocrinological disorders. Event-free and overall survival at 2 and 5 years were 80% and 72.7%, respectively, with a mean follow-up of 48 months (range, 7-107). Conclusions: Despite the small number of patients, in our series, treatment with six cycles of chemotherapy and RTV with focal boost for localized disease (n=11) and ACST for identified slow responders (n=2) seem to be effective strategies contributing to the overall effort to improve outcomes of this group of patients.

13.
Bone ; 181: 117035, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38342278

RESUMEN

Legalized use of cannabis for medical or recreational use is becoming more and more common. With respect to potential side-effects on bone health only few clinical trials have been conducted - and with opposing results. Therefore, it seems that there is a need for more knowledge on the potential effects of cannabinoids on human bone cells. We studied the effect of cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) (dose range from 0.3 to 30 µM) on human osteoclasts in mono- as well as in co-cultures with human osteoblast lineage cells. We have used CD14+ monocytes from anonymous blood donors to differentiate into osteoclasts, and human osteoblast lineage cells from outgrowths of human trabecular bone. Our results show that THC and CBD have dose-dependent effects on both human osteoclast fusion and bone resorption. In the lower dose ranges of THC and CBD, osteoclast fusion was unaffected while bone resorption was increased. At higher doses, both osteoclast fusion and bone resorption were inhibited. In co-cultures, both osteoclastic bone resorption and alkaline phosphatase activity of the osteoblast lineage cells were inhibited. Finally, we observed that the cannabinoid receptor CNR2 is more highly expressed than CNR1 in CD14+ monocytes and pre-osteoclasts, but also that differentiation to osteoclasts was coupled to a reduced expression of CNR2, in particular. Interestingly, under co-culture conditions, we only detected the expression of CNR2 but not CNR1 for both osteoclast as well as osteoblast lineage nuclei. In line with the existing literature on the effect of cannabinoids on bone cells, our current study shows both stimulatory and inhibitory effects. This highlights that potential unfavorable effects of cannabinoids on bone cells and bone health is a complex matter. The contradictory and lacking documentation for such potential unfavorable effects on bone health as well as other potential effects, should be taken into consideration when considering the use of cannabinoids for both medical and recreational use.


Asunto(s)
Resorción Ósea , Cannabidiol , Cannabinoides , Humanos , Cannabidiol/farmacología , Cannabidiol/metabolismo , Osteoclastos/metabolismo , Dronabinol/farmacología , Dronabinol/metabolismo , Cannabinoides/farmacología , Cannabinoides/metabolismo , Resorción Ósea/metabolismo
14.
Leukemia ; 38(2): 291-301, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38182819

RESUMEN

Internal tandem duplication mutations in fms-like tyrosine kinase 3 (FLT3-ITD) are recurrent in acute myeloid leukemia (AML) and increase the risk of relapse. Clinical responses to FLT3 inhibitors (FLT3i) include myeloid differentiation of the FLT3-ITD clone in nearly half of patients through an unknown mechanism. We identified enhancer of zeste homolog 2 (EZH2), a component of polycomb repressive complex 2 (PRC2), as a mediator of this effect using a proteomic-based screen. FLT3i downregulated EZH2 protein expression and PRC2 activity on H3K27me3. FLT3-ITD and loss-of-function mutations in EZH2 are mutually exclusive in human AML. We demonstrated that FLT3i increase myeloid maturation with reduced stem/progenitor cell populations in murine Flt3-ITD AML. Combining EZH1/2 inhibitors with FLT3i increased terminal maturation of leukemic cells and reduced leukemic burden. Our data suggest that reduced EZH2 activity following FLT3 inhibition promotes myeloid differentiation of FLT3-ITD leukemic cells, providing a mechanistic explanation for the clinical observations. These results demonstrate that in addition to its known cell survival and proliferation signaling, FLT3-ITD has a second, previously undefined function to maintain a myeloid stem/progenitor cell state through modulation of PRC2 activity. Our findings support exploring EZH1/2 inhibitors as therapy for FLT3-ITD AML.


Asunto(s)
Leucemia Mieloide Aguda , Proteínas Tirosina Quinasas , Humanos , Animales , Ratones , Proteínas Tirosina Quinasas/genética , Complejo Represivo Polycomb 2/genética , Proteómica , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Tirosina Quinasa 3 Similar a fms/genética , Tirosina Quinasa 3 Similar a fms/uso terapéutico
15.
Acta Biomater ; 173: 298-313, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37979636

RESUMEN

3D bioprinting enables the fabrication of biomimetic cell-laden constructs for cartilage regeneration, offering exclusive strategies for precise pharmacological screenings in osteoarthritis (OA). Synovial inflammation plays a crucial role in OA's early stage and progression, characterized by the increased of the synovial pro-inflammatory mediators and cytokines and chondrocyte apoptosis. Therefore, there is an urgent need to develop solutions for effectively managing the primary events associated with OA. To address these issues, a phenolic-based biocompatible ionic liquid approach, combining alginate (ALG), acemannan (ACE), and cholinium caffeate (Ch[Caffeate]), was used to produce easily printable bioinks. Through the use of this strategy 3D constructs with good printing resolution and high structural integrity were obtained. The encapsulation of chondrocytes like ATDC5 cells provided structures with good cell distribution, viability, and growth, for up to 14 days. The co-culture of the constructs with THP-1 macrophages proved their ability to block pro-inflammatory cytokines (TNF-α and IL-6) and mediators (GM-CSF), released by the cultured cells. Moreover, incorporating the biocompatible ionic liquid into the system significantly improved its bioactive performance without compromising its physicochemical features. These findings demonstrate that ALG/ACE/Ch[Caffeate] bioinks have great potential for bioengineering cartilage tissue analogs. Besides, the developed ALG/ACE/Ch[Caffeate] bioinks protected encapsulated chondrocyte-like cells from the effect of the inflammation, assessed by a co-culture system with THP-1 macrophages. These results support the increasing use of Bio-ILs in the biomedical field, particularly for developing 3D bioprinting-based constructs to manage inflammatory-based changes in OA. STATEMENT OF SIGNIFICANCE: Combining natural resources with active biocompatible ionic liquids (Bio-IL) for 3D printing is herein presented as an approach for the development of tools to manage inflammatory osteoarthritis (OA). We propose combining alginate (ALG), acemannan (ACE), and cholinium caffeate (Ch[Caffeate]), a phenolic-based Bio-IL with anti-inflammatory and antioxidant features, to produce bioinks that allow to obtain 3D constructs with good printing resolution, structural integrity, and that provide encapsulated chondrocyte-like cells good viability. The establishment of a co-culture system using the printed constructs and THP-1-activated macrophages allowed us to study the encapsulated chondrocyte-like cells behaviour within an inflammatory scenario, a typical event in early-stage OA. The obtained outcomes support the beneficial use of Bio-ILs in the biomedical field, particularly for the development of 3D bioprinting-based models that allow the monitoring of inflammatory-based events in OA.


Asunto(s)
Bioimpresión , Líquidos Iónicos , Osteoartritis , Humanos , Líquidos Iónicos/farmacología , Citocinas , Osteoartritis/tratamiento farmacológico , Inflamación , Antiinflamatorios/farmacología , Alginatos/farmacología , Alginatos/química , Impresión Tridimensional , Ingeniería de Tejidos/métodos , Bioimpresión/métodos , Andamios del Tejido/química
16.
Biometals ; 37(2): 321-336, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37917351

RESUMEN

Candida spp. are the commonest fungal pathogens worldwide. Antifungal resistance is a problem that has prompted the discovery of novel anti-Candida drugs. Herein, 25 compounds, some of them containing copper(II), cobalt(II) and manganese(II) ions, were initially evaluated for inhibiting the growth of reference strains of Candida albicans and Candida tropicalis. Eight (32%) of the compounds inhibited the proliferation of these yeasts, displaying minimum inhibitory concentrations (MICs) ranging from 31.25 to 250 µg/mL and minimum fungicidal concentration (MFCs) from 62.5 to 250 µg/mL. Drug-likeness/pharmacokinetic calculated by SwissADME indicated that the 8 selected compounds were suitable for use as topical drugs. The complex CTP, Cu(theo)2phen(H2O).5H2O (theo = theophylline; phen = 1,10-phenanthroline), was chosen for further testing against 10 medically relevant Candida species that were resistant to fluconazole/amphotericin B. CTP demonstrated a broad spectrum of action, inhibiting the growth of all 20 clinical fungal isolates, with MICs from 7.81 to 62.5 µg/mL and MFCs from 15.62 to 62.5 µg/mL. Conversely, CTP did not cause lysis in erythrocytes. The toxicity of CTP was evaluated in vivo using Galleria mellonella and Tenebrio molitor. CTP had no or low levels of toxicity at doses ranging from 31.25 to 250 µg/mL for 5 days. After 24 h of treatment, G. mellonella larvae exhibited high survival rates even when exposed to high doses of CTP (600 µg/mL), with the 50% cytotoxic concentration calculated as 776.2 µg/mL, generating selectivity indexes varying from 12.4 to 99.4 depending on each Candida species. These findings suggest that CTP could serve as a potential drug to treat infections caused by Candida species resistant to clinically available antifungals.


Asunto(s)
Antifúngicos , Candida , Fenantrolinas , Antifúngicos/farmacología , Antifúngicos/química , Cobre/farmacología , Teofilina/farmacología , Candida albicans , Farmacorresistencia Fúngica , Pruebas de Sensibilidad Microbiana
17.
J Pediatr (Rio J) ; 100(1): 32-39, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37690464

RESUMEN

OBJECTIVE: To evaluate the effect of oropharyngeal colostrum immunotherapy (OCI) on the mortality of preterm newborns (PTNB) with very low birth weight (VLBW). METHOD: Non-randomized clinical trial, carried out with 138 mother-child pairs attended at a public maternity hospital. The treatment group used raw colostrum, dripping 4 drops (0.2 ml) into the oropharyngeal mucosa, totaling 8 administrations in 24 h, up to the 7th complete day of life (OCI). The control group was composed of newborns admitted to the same maternity hospital before the implementation of the OCI. Analyzes were performed: descriptive, bivariate, multiple logistic regression, and survival analysis, with a significance level of 5% and 95% CI. RESULTS: The treatment group had an RR of death of 0.26 (95% CI = 0.07-0.67; p = 0.00), adjusted for maternal age, marital status, gestational hypertension, type of delivery, number of prenatal visits, and birth weight. Number Needed to Treat (NNT) demonstrated that for every 5 individuals treated with OCI, one death was prevented NNT = 4.9 (95% CI = 1.84-5.20); however, for PTNB with VLBW who remained hospitalized for 50, 100 and 150 days, the NNT reduces to 4, 4 and 3, respectively. CONCLUSION: The OCI proved to be a beneficial intervention, since it reduced the risk of mortality in PTNB with VLBW when compared to the control group.


Asunto(s)
Calostro , Nacimiento Prematuro , Recién Nacido , Humanos , Femenino , Embarazo , Recién Nacido de muy Bajo Peso , Peso al Nacer , Inmunoterapia , Conducta de Reducción del Riesgo
18.
J. pediatr. (Rio J.) ; J. pediatr. (Rio J.);100(1): 32-39, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1528967

RESUMEN

Abstract Objective To evaluate the effect of oropharyngeal colostrum immunotherapy (OCI) on the mortality of preterm newborns (PTNB) with very low birth weight (VLBW). Method Non-randomized clinical trial, carried out with 138 mother-child pairs attended at a public maternity hospital. The treatment group used raw colostrum, dripping 4 drops (0.2 ml) into the oropharyngeal mucosa, totaling 8 administrations in 24 h, up to the 7th complete day of life (OCI). The control group was composed of newborns admitted to the same maternity hospital before the implementation of the OCI. Analyzes were performed: descriptive, bivariate, multiple logistic regression, and survival analysis, with a significance level of 5% and 95% CI. Results The treatment group had an RR of death of 0.26 (95% CI = 0.07-0.67; p= 0.00), adjusted for maternal age, marital status, gestational hypertension, type of delivery, number of prenatal visits, and birth weight. Number Needed to Treat (NNT) demonstrated that for every 5 individuals treated with OCI, one death was prevented NNT = 4.9 (95% CI = 1.84-5.20); however, for PTNB with VLBW who remained hospitalized for 50, 100 and 150 days, the NNT reduces to 4, 4 and 3, respectively. Conclusion The OCI proved to be a beneficial intervention, since it reduced the risk of mortality in PTNB with VLBW when compared to the control group.

19.
J Fungi (Basel) ; 9(8)2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37623630

RESUMEN

Echinocandins, used for the prevention and treatment of invasive fungal infections, have led to a rise in breakthrough infections caused by resistant Candida species. Among these species, those belonging to the Candida haemulonii complex are rare multidrug-resistant (MDR) yeasts that are frequently misidentified but have emerged as significant healthcare-associated pathogens causing invasive infections. The objectives of this study were to investigate the evolutionary pathways of echinocandin resistance in C. haemulonii by identifying mutations in the FKS1 gene and evaluating the impact of resistance on fitness. After subjecting a MDR clinical isolate of C. haemulonii (named Ch4) to direct selection using increasing caspofungin concentrations, we successfully obtained an isolate (designated Ch4'r) that exhibited a high level of resistance, with MIC values exceeding 16 mg/L for all tested echinocandin drugs (caspofungin, micafungin, and anidulafungin). Sequence analysis revealed a specific mutation in the resistant Ch4'r strain, leading to an arginine-histidine amino acid substitution (R1354H), occurring at the G4061A position of the HS2 region of the FKS1 gene. Compared to the wild-type strain, Ch4'r exhibited significantly reduced growth proliferation, biofilm formation capability, and phagocytosis ratio, indicating a decrease in fitness. Transmission electron microscopy analysis revealed alterations in cell wall components, with a notable increase in cell wall thickness. The resistant strain also exhibited higher amounts (2.5-fold) of chitin, a cell wall-located molecule, compared to the wild-type strain. Furthermore, the resistant strain demonstrated attenuated virulence in the Galleria mellonella larval model. The evolved strain Ch4'r maintained its resistance profile in vivo since the treatment with either caspofungin or micafungin did not improve larval survival or reduce the fungal load. Taken together, our findings suggest that the acquisition of pan-echinocandin resistance occurred rapidly after drug exposure and was associated with a significant fitness cost in C. haemulonii. This is particularly concerning as echinocandins are often the first-line treatment option for MDR Candida species.

20.
Trop Med Infect Dis ; 8(8)2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37624333

RESUMEN

Chagas disease is an emerging and neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi, estimated to infect 8 to 10 million people worldwide, according to the World Health Organization [...].

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