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1.
Animals (Basel) ; 14(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38396603

RESUMO

Proteinaceous toxins are peptides or proteins that hold great biotechnological value, evidenced by their ecological role, whether as defense or predation mechanisms. Bioprospecting using bioinformatics and omics may render screening for novel bioactives more expeditious, especially considering the immense diversity of toxin-secreting marine organisms. Eulalia sp. (Annelida: Phyllodocidae), a toxin bearing marine annelid, was recently shown to secrete cysteine-rich protein (Crisp) toxins (hitherto referred to as 'phyllotoxins') that can immobilize its prey. By analyzing and validating transcriptomic data, we narrowed the list of isolated full coding sequences of transcripts of the most abundant toxins or accompanying bioactives secreted by the species (the phyllotoxin Crisp, hyaluronidase, serine protease, and peptidases M12A, M13, and M12B). Through homology matching with human proteins, the biotechnological potential of the marine annelid's toxins and related proteins was tentatively associated with coagulative and anti-inflammatory responses for the peptidases PepM12A, SePr, PepM12B, and PepM13, and with the neurotoxic activity of Crisp, and finally, hyaluronidase was inferred to bear properties of an permeabilizing agent. The in silico analysis succeeded by validation by PCR and Sanger sequencing enabled us to retrieve cDNAs can may be used for the heterologous expression of these toxins.

2.
Toxins (Basel) ; 15(11)2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37999518

RESUMO

The immense biodiversity of marine invertebrates makes them high-value targets for the prospecting of novel bioactives. The present study investigated proteinaceous toxins secreted by the skin and proboscis of Glycera alba (Annelida: Polychaeta), whose congenerics G. tridactyla and G. dibranchiata are known to be venomous. Proteomics and bioinformatics enabled the detection of bioactive proteins that hold potential for biotechnological applications, including toxins like glycerotoxins (GLTx), which can interfere with neuromuscular calcium channels and therefore have value for the development of painkillers, for instance. We also identified proteins involved in the biosynthesis of toxins. Other proteins of interest include venom and toxin-related bioactives like cysteine-rich venom proteins, many of which are known to interfere with the nervous system. Ex vivo toxicity assays with mussel gills exposed to fractionated protein extracts from the skin and proboscis revealed that fractions potentially containing higher-molecular-mass venom proteins can exert negative effects on invertebrate prey. Histopathology, DNA damage and caspase-3 activity suggest significant cytotoxic effects that can be coadjuvated by permeabilizing enzymes such as venom metalloproteinases M12B. Altogether, these encouraging findings show that venomous annelids are important sources of novel bioactives, albeit illustrating the challenges of surveying organisms whose genomes and metabolisms are poorly understood.


Assuntos
Anelídeos , Poliquetos , Toxinas Biológicas , Animais , Anelídeos/genética , Invertebrados , Organismos Aquáticos
3.
Mar Drugs ; 20(4)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35447897

RESUMO

The vast ocean holds many unexplored organisms with unique adaptive features that enable them to thrive in their environment. The secretion of fluorescent proteins is one of them, with reports on the presence of such compounds in marine annelids being scarce. The intertidal Eulalia sp. is an example. The worm secretes copious amounts of mucus, that when purified and concentrated extracts, yield strong fluorescence under UV light. Emission has two main maxima, at 400 nm and at 500 nm, with the latter responsible for the blue-greenish fluorescence. Combining proteomics and transcriptomics techniques, we identified ubiquitin, peroxiredoxin, and 14-3-3 protein as key elements in the mucus. Fluorescence was found to be mainly modulated by redox status and pH, being consistently upheld in extracts prepared in Tris-HCl buffer with reducing agent at pH 7 and excited at 330 nm. One of the proteins associated with the fluorescent signal was localized in secretory cells in the pharynx. The results indicate that the secretion of fluorescent proteinaceous complexes can be an important defense against UV for this dweller. Additionally, the internalization of fluorescent complexes by ovarian cancer cells and modulation of fluorescence of redox status bears important considerations for biotechnological application of mucus components as markers.


Assuntos
Anelídeos , Poliquetos , Animais , Biotecnologia , Corantes/metabolismo , Humanos , Muco/química , Extratos Vegetais/análise , Poliquetos/química , Proteínas/análise
4.
Reumatol Clin (Engl Ed) ; 18(3): 184-185, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35277216

RESUMO

We present the case of a 36-year-old woman with diffuse idiopathic skeletal hyperostosis especially at cervical spine since she was 29 years old. The only relevant feature was the use of isotretinoin at regular doses in the past for severe acne.


Assuntos
Hiperostose Esquelética Difusa Idiopática , Isotretinoína , Adulto , Vértebras Cervicais , Feminino , Humanos , Hiperostose Esquelética Difusa Idiopática/induzido quimicamente , Hiperostose Esquelética Difusa Idiopática/diagnóstico por imagem , Isotretinoína/efeitos adversos
5.
Reumatol. clín. (Barc.) ; 18(3): 184-185, Mar 2022. ilus
Artigo em Inglês | IBECS | ID: ibc-204807

RESUMO

We present the case of a 36-year-old woman with diffuse idiopathic skeletal hyperostosis especially at cervical spine since she was 29 years old. The only relevant feature was the use of isotretinoin at regular doses in the past for severe acne.(AU)


Se presenta el caso de una paciente de 36 años con hiperostosis anquilosante vertebral difusa de predominio cervical desde los 29 años. El único antecedente a destacar es el uso de isotretinoína a dosis adecuadas para el tratamiento de acné severo.(AU)


Assuntos
Humanos , Adulto , Hiperostose Esquelética Difusa Idiopática , Isotretinoína/farmacocinética , Acne Vulgar , Acne Vulgar/tratamento farmacológico , Reumatologia
6.
Elife ; 102021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34844669

RESUMO

Dinosaur bonebeds with amber content, yet scarce, offer a superior wealth and quality of data on ancient terrestrial ecosystems. However, the preserved palaeodiversity and/or taphonomic characteristics of these exceptional localities had hitherto limited their palaeobiological potential. Here, we describe the amber from the Lower Cretaceous dinosaur bonebed of Ariño (Teruel, Spain) using a multidisciplinary approach. Amber is found in both a root layer with amber strictly in situ and a litter layer mainly composed of aerial pieces unusually rich in bioinclusions, encompassing 11 insect orders, arachnids, and a few plant and vertebrate remains, including a feather. Additional palaeontological data-charophytes, palynomorphs, ostracods- are provided. Ariño arguably represents the most prolific and palaeobiologically diverse locality in which fossiliferous amber and a dinosaur bonebed have been found in association, and the only one known where the vast majority of the palaeontological assemblage suffered no or low-grade pre-burial transport. This has unlocked unprecedentedly complete and reliable palaeoecological data out of two complementary windows of preservation-the bonebed and the amber-from the same site.


Assuntos
Âmbar , Dinossauros , Fósseis , Animais , Biodiversidade , Florestas , Solo , Espanha , Áreas Alagadas
7.
ARS med. (Santiago, En línea) ; 46(3): 40-46, ago. 20, 2021.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1363709

RESUMO

Introducción: el profesionalismo es clave para construir la identidad de los profesionales sanitarios. El objetivo de este trabajo ha sido conocer en un colectivo de residentes, la influencia de la primera ola de la pandemia por SARS-CoV2 en sus competencias del profesionalismo. Materiales y métodos: estudio descriptivo transversal mediante cuestionario electrónico, remitido a 167 residentes, para medir su percepción sobre el impacto de la pandemia COVID-19 en el profesionalismo, con una escala verbal de cuatro niveles: excelente, por encima de lo esperado, lo esperado, por debajo de lo esperado. Se realizó, además, una pregunta abierta de "reflexión personal" analizada cualitativamente mediante un proceso de triangulación. La encuesta se hizo en el Hospital Universitario Fundación Alcorcón en los dos meses siguientes a la primera ola pandémica. Resultados: respondieron 59 residentes (35,3%) de 21 especialidades. Sus lugares de trabajo fueron muy variados. Los atributos del profesionalismo valorados por encima de esperado o excelente fueron: trabajo en equipo (74,6%), empatía (71,2%) y responder a las necesidades del paciente por encima de las propias (69,5%). Se encontró por debajo de lo esperado la gestión de las emociones (22%). Discusión: la pandemia COVID-19 ha contribuido a reforzar la identidad profesional de los residentes, manifestándose a través de muchas dimensiones del profesionalismo. La gestión de las emociones fue la que obtuvo menor valoración.


Introduction: Professionalism is essential to build the identity of health professionals. The aim in this study was to determine, in a group of residents, the influence of the first wave of SARS-CoV2 pandemic on their professionalism competencies. Methods: Cross-sectional descriptive study with an electronic survey sent to 167 residents of Hospital Universitario Fundación Alcorcón to assess their perception of the impact of COVID-19 pandemic on professionalism, with a four-level verbal scale: excellent, above expected, expected, below expected. In addition, an open-ended "personal reflection" question was qualitatively analyzed through a triangulation process. The survey was completed immediately after the first pandemic wave. Results: The questionnaire was answered by 59 residents (35.3%) of 21 specialties from different workplaces. The attributes of professionalism rated above expected or excellent were: teamwork (74.6%), empathy (71.2%) and responding to patient's needs above their own (69.5%). Management of emotions (21%) was found to be below expectations. Discussion: COVID-19 pandemic has contributed to reinforce the professional identity of the residents, expressing itself through many dimensions of professionalism. Emotional management was the lowest rated.

8.
Molecules ; 26(13)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34198975

RESUMO

The past decade has seen growing interest in marine natural pigments for biotechnological applications. One of the most abundant classes of biological pigments is the tetrapyrroles, which are prized targets due their photodynamic properties; porphyrins are the best known examples of this group. Many animal porphyrinoids and other tetrapyrroles are produced through heme metabolic pathways, the best known of which are the bile pigments biliverdin and bilirubin. Eulalia is a marine Polychaeta characterized by its bright green coloration resulting from a remarkably wide range of greenish and yellowish tetrapyrroles, some of which have promising photodynamic properties. The present study combined metabolomics based on HPLC-DAD with RNA-seq transcriptomics to investigate the molecular pathways of porphyrinoid metabolism by comparing the worm's proboscis and epidermis, which display distinct pigmentation patterns. The results showed that pigments are endogenous and seemingly heme-derived. The worm possesses homologs in both organs for genes encoding enzymes involved in heme metabolism such as ALAD, FECH, UROS, and PPOX. However, the findings also indicate that variants of the canonical enzymes of the heme biosynthesis pathway can be species- and organ-specific. These differences between molecular networks contribute to explain not only the differential pigmentation patterns between organs, but also the worm's variety of novel endogenous tetrapyrrolic compounds.


Assuntos
Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Metabolômica/métodos , Poliquetos/genética , Tetrapirróis/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Epiderme/metabolismo , Redes e Vias Metabólicas , Especificidade de Órgãos , Fármacos Fotossensibilizantes/metabolismo , Poliquetos/metabolismo , Análise de Sequência de RNA , Especificidade da Espécie , Tetrapirróis/genética
9.
Adv Sci (Weinh) ; 8(14): e2101058, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34029010

RESUMO

This paper reports the use of a self-assembling hydrogel as a delivery vehicle for the Parkinson's disease drug l-DOPA. Based on a two-component combination of an l-glutamine amide derivative and benzaldehyde, this gel has very soft rheological properties and self-healing characteristics. It is demonstrated that the gel can be formulated to encapsulate l-DOPA. These drug-loaded gels are characterized, and rapid release of the drug is obtained from the gel network. This drug-loaded hydrogel has appropriate rheological characteristics to be amenable for injection. This system is therefore tested as a vehicle for nasal delivery of neurologically-active drugs-a drug delivery strategy that can potentially avoid first pass liver metabolism and bypass the blood-brain barrier, hence enhancing brain uptake. In vitro tests indicate that the gel has biocompatibility with respect to nasal epithelial cells. Furthermore, animal studies demonstrate that the nasal delivery of a gel loaded with 3 H-labeled l-DOPA out-performed a simple intranasal l-DOPA solution. This is attributed to longer residence times of the gel in the nasal cavity resulting in increased blood and brain concentrations. It is demonstrated that the likely routes of brain penetration of intranasally-delivered l-DOPA gel involve the trigeminal and olfactory nerves connecting to other brain regions.


Assuntos
Antiparkinsonianos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Hidrogéis/administração & dosagem , Levodopa/administração & dosagem , Administração Intranasal , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Mucosa Nasal/metabolismo
10.
Toxins (Basel) ; 13(2)2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525375

RESUMO

The growing number of known venomous marine invertebrates indicates that chemical warfare plays an important role in adapting to diversified ecological niches, even though it remains unclear how toxins fit into the evolutionary history of these animals. Our case study, the Polychaeta Eulalia sp., is an intertidal predator that secretes toxins. Whole-transcriptome sequencing revealed proteinaceous toxins secreted by cells in the proboscis and delivered by mucus. Toxins and accompanying enzymes promote permeabilization, coagulation impairment and the blocking of the neuromuscular activity of prey upon which the worm feeds by sucking pieces of live flesh. The main neurotoxins ("phyllotoxins") were found to be cysteine-rich proteins, a class of substances ubiquitous among venomous animals. Some toxins were phylogenetically related to Polychaeta, Mollusca or more ancient groups, such as Cnidaria. Some toxins may have evolved from non-toxin homologs that were recruited without the reduction in molecular mass and increased specificity of other invertebrate toxins. By analyzing the phylogeny of toxin mixtures, we show that Polychaeta is uniquely positioned in the evolution of animal venoms. Indeed, the phylogenetic models of mixed or individual toxins do not follow the expected eumetazoan tree-of-life and highlight that the recruitment of gene products for a role in venom systems is complex.


Assuntos
Perfilação da Expressão Gênica , Poliquetos/genética , Proteínas/genética , Transcriptoma , Peçonhas/genética , Animais , Filogenia , Poliquetos/metabolismo , Proteínas/metabolismo , Peçonhas/metabolismo , Sequenciamento do Exoma
11.
J Med Case Rep ; 15(1): 89, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608032

RESUMO

BACKGROUND: Tumor molecular screening allows categorization of molecular alterations to select the best therapeutic strategy. AT-rich interactive domain-containing 1A (ARID1A) gene mutations are present in gastric, endometrial, and clear cell ovarian tumors. Inactivation of this gene impairs mismatch repair (MMR) machinery leading to an increased mutation burden that correlates with microsatellite instability (MSI), associated with tumor-infiltrating lymphocytes and programmed death ligand 1 (PD-L1) expression. This is the first case report in lung adenocarcinoma of ARID1A gene alterations leading to sporadic MSI, through somatic mutL homolog 1 (MLH1) promoter methylation, with an MLH1 gene mutation as the second somatic hit. CASE PRESENTATION: A 50-year-old never-smoker Bulgarian woman, with no comorbidities and no family history of cancer, was diagnosed with metastatic lung adenocarcinoma. PD-L1 immunohistochemistry (IHC) of tissue biopsies on right groin adenopathies resulted in 30% positivity. Liquid biopsy test reported actionable alterations in ARID1A gene, rearranged during transfection (RET) gene fusions, epidermal growth factor receptor (EGFR) gene R776H mutation, breast cancer (BRCA) genes 1/2, and cyclin-dependent kinase inhibitor 2A (CDKN2A) gene mutations. The patient was treated with immunotherapy, and showed a treatment response lasting for 19 months until a new metastasis appeared at the right deltoid muscle. Genomic analysis of a sample of this metastasis confirmed PD-L1 positivity of greater than 50% with CD8+ T cells expression and showed MSI with a deleterious c.298C>T (p.R100*) MLH1 gene mutation. Multiplex ligation-dependent probe amplification (MLPA) of this sample unveiled MLH1 gene promoter methylation. The MLH1 gene mutation and the MLH1 gene methylation were not present at the germline setting. CONCLUSIONS: In this particular case, we show that ARID1A gene mutations with sporadic MSI due to somatic MLH1 gene promoter methylation and MLH1 gene mutation could change the prognosis and define the response to immunotherapy in a patient with lung adenocarcinoma. Comprehensive solid and liquid biopsy tests are useful to find out resistance mechanisms to immune checkpoint inhibitors. Our data encourages the development of new therapies against ARID1A mutations and epigenomic methylation when involved in MSI neoplasms.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Linfócitos T CD8-Positivos/metabolismo , Proteínas de Ligação a DNA , Feminino , Genômica , Humanos , Imunoterapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Metilação , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL/genética , Proteína 1 Homóloga a MutL/metabolismo , Mutação , Fatores de Transcrição
12.
Mar Drugs ; 19(1)2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33445445

RESUMO

As Yondelis joins the ranks of approved anti-cancer drugs, the benefit from exploring the oceans' biodiversity becomes clear. From marine toxins, relevant bioproducts can be obtained due to their potential to interfere with specific pathways. We explored the cytotoxicity of toxin-bearing secretions of the polychaete Eulalia onto a battery of normal and cancer human cell lines and discovered that the cocktail of proteins is more toxic towards an ovarian cancer cell line (A2780). The secretions' main proteins were identified by proteomics and transcriptomics: 14-3-3 protein, Hsp70, Rab3, Arylsulfatase B and serine protease, the latter two being known toxins. This mixture of toxins induces cell-cycle arrest at G2/M phase after 3h exposure in A2780 cells and extrinsic programmed cell death. These findings indicate that partial re-activation of the G2/M checkpoint, which is inactivated in many cancer cells, can be partly reversed by the toxic mixture. Protein-protein interaction networks partake in two cytotoxic effects: cell-cycle arrest with a link to RAB3C and RAF1; and lytic activity of arylsulfatases. The discovery of both mechanisms indicates that venomous mixtures may affect proliferating cells in a specific manner, highlighting the cocktails' potential in the fine-tuning of anti-cancer therapeutics targeting cell cycle and protein homeostasis.


Assuntos
Anelídeos , Antineoplásicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Toxinas Marinhas/uso terapêutico , Neoplasias Ovarianas/patologia , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Proliferação de Células/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Feminino , Células HCT116 , Humanos , Células K562 , Células MCF-7 , Toxinas Marinhas/isolamento & purificação , Toxinas Marinhas/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo
13.
Diabet Med ; 38(3): e14502, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33368612

RESUMO

OBJECTIVES: To assess the efficacy of glucagon-like peptide-1 receptor agonists (GLP1-RAs) and sodium-glucose co-transporter 2 (SGLT2) inhibitors, administered without metformin on cardiovascular outcomes in type 2 diabetes patients. METHODS: A systematic review was performed according to Cochrane's methodological standards. We included randomized clinical trials (RCTs) on adult type 2 diabetes patients, assessing the efficacy of SGLT2 inhibitors and GLP1-RAs compared to other glucose-lowering drugs and/or RCTs that presented data of a subgroup of type 2 diabetes patients without metformin use at baseline. The main outcome was the reduction of the risk of any major adverse cardiovascular events (MACE) reported individually or as a composite outcome. RESULTS: Five RCTs including 50,725 type 2 diabetes patients, of whom 10,013 had not received metformin, were included in this meta-analysis. Three of these studies assessed the efficacy of GLP1-RAs and two of SGLT2 inhibitors. In patients without metformin at baseline, GLP1-RAs in comparison with placebo reduced the risk of MACE significantly by 20% (HR: 0.80; 95% CI: 0.71-0.89). SGLT2 inhibitors also significantly reduced the risk of MACE by 32% (HR: 0.68; 95% CI: 0.57-0.81). CONCLUSIONS: SGLT2 inhibitors and GLP1-RAs provided without metformin at baseline may reduce the risk of MACE in comparison with placebo in type 2 diabetes patients at increased risk of cardiovascular events.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Inibidores do Transportador 2 de Sódio-Glicose/administração & dosagem , Adulto , Diabetes Mellitus Tipo 2/epidemiologia , Angiopatias Diabéticas/prevenção & controle , Quimioterapia Combinada , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Humanos , Hipoglicemiantes/classificação , Metformina/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos
14.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33139176

RESUMO

We present the case of a 36-year-old woman with diffuse idiopathic skeletal hyperostosis especially at cervical spine since she was 29 years old. The only relevant feature was the use of isotretinoin at regular doses in the past for severe acne.

15.
Sci Rep ; 10(1): 9751, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546844

RESUMO

Fossilized remains preserved in amber provide abundant data on the paleobiota surrounding the resin-producing plants, but relatively scarcer information about the resinous sources themselves. Here, dark pseudoinclusions in kidney-shaped amber pieces from the Early Cretaceous (Albian) amber from Spain are studied. This type of fossilized remain, abundant in Cretaceous ambers, was first interpreted as fossilized vacuole-bearing microorganisms, but later regarded as artifactual and probably secreted by the resinous trees, although their origin remained unclear. Using complementary microscopy (light, electron, confocal), spectroscopy (infrared, micro-Raman), mass spectrometry and elemental analysis techniques, we demonstrate that the pseudoinclusions correspond to droplets of phloem sap containing amber spheroids and preserving both organic and inorganic residues consistent with degraded components from the original sap. The amber pieces containing pseudoinclusions are fossilized, resin-in-sap-in-resin double emulsions, showing banding patterns with differential content of resin-in-sap emulsion droplets. Our findings represent the first time fossilized phloem sap, 105 million years old, has been recognized and characterized, and open new lines of paleontological research with taxonomic, taphonomic, physiological and ecological implications.


Assuntos
Âmbar/química , Fósseis/diagnóstico por imagem , Paleontologia/métodos , Âmbar/análise , Emulsões/análise , Microscopia Eletrônica de Varredura/métodos , Floema/química , Preservação Biológica/métodos , Espanha , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos
16.
Biomater Sci ; 7(9): 3812-3820, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31264671

RESUMO

Self-assembled cationic micelles are an attractive platform for binding biologically-relevant polyanions such as heparin. This has potential applications in coagulation control, where a synthetic heparin rescue agent could be a useful replacement for protamine, which is in current clinical use. However, micelles can have low stability in human serum and unacceptable toxicity profiles. This paper reports the optimisation of self-assembled multivalent (SAMul) arrays of amphiphilic ligands to bind heparin in competitive conditions. Specifically, modification of the hydrophobic unit kinetically stabilises the self-assembled nanostructures, preventing loss of binding ability in the presence of human serum - cholesterol hydrophobic units significantly outperform systems with a simple aliphatic chain. It is demonstrated that serum albumin disrupts the binding thermodynamics of the latter system. Molecular simulation shows aliphatic lipids can more easily be removed from the self-assembled nanostructures than the cholesterol analogues. This agrees with the experimental observation that the cholesterol-based systems undergo slower disassembly and subsequent degradation via ester hydrolysis. Furthermore, by stabilising the SAMul nanostructures, toxicity towards human cells is decreased and biocompatibility enhanced, with markedly improved survival of human hepatoblastoma cells in an MTT assay.


Assuntos
Colesterol/sangue , Heparina/sangue , Tensoativos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Colesterol/química , Colesterol/farmacologia , Heparina/química , Heparina/farmacologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Ligantes , Micelas , Estrutura Molecular , Nanoestruturas/química , Tensoativos/química , Tensoativos/farmacologia , Termodinâmica
17.
Environ Res ; 173: 270-280, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30928858

RESUMO

Marine biotechnology is under the spotlight, as researchers and industrialists become aware that bioprospecting through the oceans' vast biodiversity can replace the painstaking process of designing synthetic compounds. Millions of years of Natural Selection provided an almost inexhaustible source of marine products that can interfere with specific bioprocesses while being cost-effective, safer and more environmentally friendly. Still, the number of commercial applications of marine compounds, especially from eumetazoans, can seem disappointing. In most part, this results from the challenges of dealing with an immense biodiversity and with poorly known organisms with uncanny physiology. Consequently, shifting the current perspective from descriptive science to actually proposing applications can be a major incentive to industry. With this in mind, the present review focuses on one of the least studied but most representative group of marine animals: the Polychaeta annelids. Occupying nearly every marine habitat, from the deep sea to the intertidal, they can offer a wide array of natural products that are just beginning to be understood, showing properties compatible with anaesthetics, fluorescent probes, and even antibiotics and pesticides, for instance. Altogether, they are a showcase for the ocean's real biotechnological deterrent, albeit our still wispy knowledge on this vast and ancient environment.


Assuntos
Poliquetos , Animais , Organismos Aquáticos , Biodiversidade , Biotecnologia , Invertebrados , Oceanos e Mares
19.
Chem Commun (Camb) ; 53(84): 11580-11583, 2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-28990600

RESUMO

We investigate the impact of an over-looked component on molecular recognition in water-buffer. The binding of a cationic dye to biological polyanion heparin is shown by isothermal calorimetry to depend on buffer (Tris-HCl > HEPES > PBS). The heparin binding of self-assembled multivalent (SAMul) cationic micelles is even more buffer dependent. Multivalent electrostatic molecular recognition is buffer dependent as a result of competitive interactions between the cationic binding interface and anions present in the buffer.


Assuntos
Heparina/química , Nanoestruturas/química , Polímeros/química , Sítios de Ligação , Soluções Tampão , Estrutura Molecular , Polieletrólitos , Eletricidade Estática , Água/química
20.
J Invest Dermatol ; 137(11): 2344-2353, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28774589

RESUMO

Mutations in ceramide biosynthesis pathways have been implicated in a few Mendelian disorders of keratinization, although ceramides are known to have key roles in several biological processes in skin and other tissues. Using whole-exome sequencing in four probands with undiagnosed skin hyperkeratosis/ichthyosis, we identified compound heterozygosity for mutations in KDSR, encoding an enzyme in the de novo synthesis pathway of ceramides. Two individuals had hyperkeratosis confined to palms, soles, and anogenital skin, whereas the other two had more severe, generalized harlequin ichthyosis-like skin. Thrombocytopenia was present in all patients. The mutations in KDSR were associated with reduced ceramide levels in skin and impaired platelet function. KDSR enzymatic activity was variably reduced in all patients, resulting in defective acylceramide synthesis. Mutations in KDSR have recently been reported in inherited recessive forms of progressive symmetric erythrokeratoderma, but our study shows that biallelic mutations in KDSR are implicated in an extended spectrum of disorders of keratinization in which thrombocytopenia is also part of the phenotype. Mutations in KDSR cause defective ceramide biosynthesis, underscoring the importance of ceramide and sphingosine synthesis pathways in skin and platelet biology.


Assuntos
Oxirredutases do Álcool/genética , Ceramidas/biossíntese , Predisposição Genética para Doença , Ceratodermia Palmar e Plantar/complicações , Ceratodermia Palmar e Plantar/genética , Trombocitopenia/complicações , Adolescente , Alelos , Biópsia por Agulha , Criança , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Ceratodermia Palmar e Plantar/patologia , Masculino , Mutação , Linhagem , Prognóstico , Estudos de Amostragem , Índice de Gravidade de Doença , Trombocitopenia/diagnóstico , Adulto Jovem
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