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1.
Ecotoxicol Environ Saf ; 279: 116473, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38781890

RESUMEN

The toxicity of three phthalates (PAEs) - butylbenzyl phthalate (BBP), diethyl phthalate (DEP), and di-(2-ethylhexyl) phthalate (DEHP) - was tested on the Mediterranean sea urchin Paracentrotus lividus. Fertilized eggs were exposed to environmental and high PAE concentrations for 72 h. The potential toxic effects on larval development and any morphological anomalies were then assessed to estimate PAEs impact. Environmental concentrations never affected development, while high concentrations induced toxic effects in larvae exposed to BBP (EC50: 2.9 ×103 µg/L) and DEHP (EC50: 3.72 ×103 µg/L). High concentrations caused skeletal anomalies, with a slight to moderate impact for DEP/DEHP and BBP, respectively. PAE toxicity was: BBP>DEHP>DEP. In conclusion, the three PAEs at environmental concentrations do not pose a risk to sea urchins. However, PAE concentrations should be further monitored in order not to constitute a concern to marine species, especially at their early developmental stages.


Asunto(s)
Larva , Paracentrotus , Ácidos Ftálicos , Contaminantes Químicos del Agua , Animales , Ácidos Ftálicos/toxicidad , Paracentrotus/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Dietilhexil Ftalato/toxicidad
2.
Mol Cell ; 83(18): 3314-3332.e9, 2023 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-37625404

RESUMEN

Hsp104 is an AAA+ protein disaggregase that solubilizes and reactivates proteins trapped in aggregated states. We have engineered potentiated Hsp104 variants to mitigate toxic misfolding of α-synuclein, TDP-43, and FUS implicated in fatal neurodegenerative disorders. Though potent disaggregases, these enhanced Hsp104 variants lack substrate specificity and can have unfavorable off-target effects. Here, to lessen off-target effects, we engineer substrate-specific Hsp104 variants. By altering Hsp104 pore loops that engage substrate, we disambiguate Hsp104 variants that selectively suppress α-synuclein toxicity but not TDP-43 or FUS toxicity. Remarkably, α-synuclein-specific Hsp104 variants emerge that mitigate α-synuclein toxicity via distinct ATPase-dependent mechanisms involving α-synuclein disaggregation or detoxification of soluble α-synuclein conformers. Importantly, both types of α-synuclein-specific Hsp104 variant reduce dopaminergic neurodegeneration in a C. elegans model of Parkinson's disease more effectively than non-specific variants. We suggest that increasing the substrate specificity of enhanced disaggregases could be applied broadly to tailor therapeutics for neurodegenerative disease.


Asunto(s)
Enfermedades Neurodegenerativas , Proteínas de Saccharomyces cerevisiae , Animales , Humanos , alfa-Sinucleína/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo
3.
Biomed Mater ; 17(4)2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35483345

RESUMEN

Cutaneous wound healing is a complex process that leads the skin reparation with the formation of scar tissue that typically lacks skin appendages. This fact drives us to find new strategies to improve regenerative healing of the skin. This study outlines, the contribution of colloidal silica particles and oligourethane crosslinking on the collagen material properties and the effect on skin wound healing in rats. We characterized the gel properties that are key forin-situgelation, which is accomplished by the latent reactivity of oligourethane bearing blocked isocyanate groups to crosslink collagen while entrapping silica particles. The swelling/degradation behavior and the elastic modulus of the composite gel were consistent with the modification of collagen type I with oligourethane and silica. On the other hand, these gels were characterized as scaffold for murine macrophages and human stem cells. The application of a composite gel dressing on cutaneous wounds showed a histological appearance of the recovered skin as intact skin; featured by the epidermis, hair follicles, sebaceous glands, subcutaneous adipose layer, and dermis. The results suggest that the collagen-based composite dressings are promising modulators in skin wound healing to achieve a regenerative skin closure with satisfactory functional and aesthetic scars.


Asunto(s)
Colágeno Tipo I , Dióxido de Silicio , Animales , Vendajes , Cicatriz , Colágeno/farmacología , Geles , Ratones , Ratas , Cicatrización de Heridas
4.
ACS Nano ; 16(2): 2133-2146, 2022 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-35130432

RESUMEN

We investigate the effects of crowding on the conformations and assembly of confined, highly charged, and thick polyelectrolyte brushes in the osmotic regime. Particle tracking experiments on increasingly dense suspensions of colloids coated with ultralong double-stranded DNA (dsDNA) fragments reveal nonmonotonic particle shrinking, aggregation, and re-entrant ordering. Theory and simulations show that aggregation and re-entrant ordering arise from the combined effect of shrinking, which is induced by the osmotic pressure exerted by the counterions absorbed in neighbor brushes and of a short-range attractive interaction competing with electrostatic repulsion. An unconventional mechanism gives origin to the short-range attraction: blunt-end interactions between stretched dsDNA fragments of neighboring brushes, which become sufficiently intense for dense and packed brushes. The attraction can be tuned by inducing free-end backfolding through the addition of monovalent salt. Our results show that base stacking is a mode parallel to hybridization to steer colloidal assembly in which attractions can be fine-tuned through salinity and, potentially, grafting density and temperature.


Asunto(s)
Coloides , ADN , Electricidad Estática
5.
Diabetes Res Clin Pract ; 175: 108797, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33845049

RESUMEN

AIM: To investigate the rate of antibiotic resistance and its main risk factors in a population of patients with diabetic foot infection (DFI) during the COVID-19 pandemic, in comparison with the population of 2019. METHODS: Two hundred and twenty-five patients with DFI were admitted in a tertiary care center from January 2019 to December 2020. Antibiotic resistance was evaluated by microbiological examination of soft tissues' or bone's biopsy. RESULTS: Compared with 2019 group (n = 105), 2020 group (n = 120) had a significantly higher prevalence of antibiotic resistance [2019 vs 2020, 36% vs 63%, P <0.001] and more often was admitted with recent or current antibiotic therapy (18% vs 52%, P <0.001), which was frequently self-administered (5% vs 30%, P = 0.032). The risk of antibiotic resistance was also higher in 2020 group [OR 95% CI, 2.90 (1.68 to 4.99)]. Prior hospitalization, antibiotic self-administration and antibiotic prescription by general practitioners resulted as independent predictors of antibiotic resistance. CONCLUSIONS: In a population of people with DFI admitted in a tertiary care center during the COVID-19 pandemic the prevalence of antibiotic resistance was higher than 2019. Previous hospitalization, antibiotic self-administration /prescription by general practitioners were related to higher risk of antibiotic resistant infections.


Asunto(s)
Antibacterianos/uso terapéutico , Pie Diabético/tratamiento farmacológico , Anciano , COVID-19 , Pie Diabético/epidemiología , Farmacorresistencia Microbiana , Femenino , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Pandemias , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2/aislamiento & purificación , Centros de Atención Terciaria
6.
Plant Sci ; 305: 110843, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33691970

RESUMEN

Wheat starch is composed of two glucose polymers, amylose and amylopectin. Although several starch synthases are responsible for its synthesis, only the waxy protein is associated with the amylose synthesis. The waxy protein composition of 45 Spanish common wheat landraces from Andalusia (southern Spain) was evaluated. Within these materials, five novel alleles for the Wx-A1 gene were detected. Four of them showed functional proteins (Wx-A1p, Wx-A1q, Wx-A1r and Wx-A1s), although some amino acid changes were found in the mature protein sequence. However, one of them (Wx-A1t) exhibited loss of the Wx-A1 protein, and its base sequence contained one large insert (1,073 bp) in the tenth exon, that interrupted the ORF of the Wx-A1 gene. This insert exhibited the characteristics of a Class II transposon of the Mutator superfamily, which had not been described previously, and has been named Baetica. The conservation of such inserts could be related to their low effect on vital properties of the plants, as occurs with most of the genes associated with technological quality. In conclusion, the evaluation of old wheat landraces showed that, in addition to their use as alternative crops, these materials could be a useful source of interesting genes in wheat quality improvement.


Asunto(s)
Amilosa/biosíntesis , Amilosa/genética , Proteínas de Plantas/metabolismo , Almidón Sintasa/genética , Almidón Sintasa/metabolismo , Triticum/genética , Triticum/metabolismo , Alelos , Productos Agrícolas/genética , Productos Agrícolas/metabolismo , Elementos Transponibles de ADN/genética , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Genes de Plantas , Variación Genética , Genotipo , Mutagénesis Insercional , Proteínas de Plantas/genética
7.
Elife ; 92020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33319748

RESUMEN

The AAA+ protein disaggregase, Hsp104, increases fitness under stress by reversing stress-induced protein aggregation. Natural Hsp104 variants might exist with enhanced, selective activity against neurodegenerative disease substrates. However, natural Hsp104 variation remains largely unexplored. Here, we screened a cross-kingdom collection of Hsp104 homologs in yeast proteotoxicity models. Prokaryotic ClpG reduced TDP-43, FUS, and α-synuclein toxicity, whereas prokaryotic ClpB and hyperactive variants were ineffective. We uncovered therapeutic genetic variation among eukaryotic Hsp104 homologs that specifically antagonized TDP-43 condensation and toxicity in yeast and TDP-43 aggregation in human cells. We also uncovered distinct eukaryotic Hsp104 homologs that selectively antagonized α-synuclein condensation and toxicity in yeast and dopaminergic neurodegeneration in C. elegans. Surprisingly, this therapeutic variation did not manifest as enhanced disaggregase activity, but rather as increased passive inhibition of aggregation of specific substrates. By exploring natural tuning of this passive Hsp104 activity, we elucidated enhanced, substrate-specific agents that counter proteotoxicity underlying neurodegeneration.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Agregación Patológica de Proteínas/patología , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , alfa-Sinucleína/metabolismo , Animales , Caenorhabditis elegans , Línea Celular , Endopeptidasa Clp/genética , Endopeptidasa Clp/metabolismo , Escherichia coli , Variación Genética/genética , Células HEK293 , Humanos , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/patología , Pliegue de Proteína , Deficiencias en la Proteostasis/genética , Deficiencias en la Proteostasis/patología , Proteína FUS de Unión a ARN/metabolismo , Saccharomyces cerevisiae
8.
Int J Gynecol Cancer ; 30(9): 1384-1389, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32474449

RESUMEN

OBJECTIVE: Ultrasound features of granulosa cell tumors of the ovary are still poorly defined. The aim of this study is to widen current knowledge on the role of sonographic gray scale and pattern recognition in the characterization of these tumors and to compare the ultrasound characteristics of primary diagnosis and recurrences. METHODS: Transvaginal ultrasound images of primary diagnosis or recurrences of histologically-confirmed granulosa cell tumors of the ovary were retrospectively retrieved from a dedicated database designed for the collection of clinical and ultrasound data from January 2001 to January 2019. All patients included were treated at San Raffaele and Santa Chiara Hospitals. Women with a concomitant diagnosis of another malignancy other than endometrial carcinoma were excluded from the study. All ultrasound images were described according to International Ovarian Tumor Analysis terminology and examined by experienced ultrasound examiners. RESULTS: A total of 27 patients were included: 24 with adult and 3 with juvenile ovarian granulosa cell tumors. At primary diagnosis, mean ovarian mass size was 103.8 mm (range 30-200). On ultrasound evaluation at primary diagnosis, 12 patients presented with a multilocular solid lesion (48%), 9 with a solid lesion (36%), and 4 with a multilocular lesion(16%). The echogenicity of the cyst was low level or anechoic, mixed, or hemorrhagic in 56.3%, 31.2%, and 12.5% of cases, respectively. Most tumors (45.1%), including first diagnosis and relapses, had a moderate to high color score on doppler evaluation. CONCLUSIONS: Our study showed that sonographic features and pattern recognition of relapses were comparable to those of tumors at primary diagnosis. In order to highlight the importance of transvaginal ultrasound evaluation during follow-up, further studies based on a standardized ultrasound characterization of ovarian masses are recommended.


Asunto(s)
Tumor de Células de la Granulosa/fisiopatología , Ultrasonografía/métodos , Femenino , Humanos , Estudios Retrospectivos
9.
Biomater Sci ; 7(11): 4547-4557, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31463512

RESUMEN

Immunomodulatory biomaterials have emerged as a promising approach to engineer wound healing. To achieve this task, the bioactivity of the biomaterials and an easy application are two key desirable characteristics. This work reports an injectable gel system containing immune cells primed for wound healing. By combining the self-assembly of type I collagen, cross-linked with trifunctional oligourethanes, and silica particle entrapment, the structured collagen network acts as a delivery vehicle for macrophages. This structured collagen network primes the macrophages for an anti-inflammatory response. Rheological measurements suggest that the mixture of liquid precursors can be safely stored at low temperatures and low pH (4 °C, pH 3) for at least one month. After pH neutralization and injection, gels with a storage modulus of 50-80 Pa are obtained in five minutes. Several immunocytochemistry and ELISA tests strongly suggest that mouse and human macrophages are stimulated by the material to up-regulate the production of anti-inflammatory cytokines, while down-regulating the production of pro-inflammatory cytokines. The injection of gel in an ex vivo inflammation model of intervertebral discs demonstrated that it is possible to transit from a pro-inflammatory to an anti-inflammatory microenvironment. Altogether, the results suggest that this gel can polarize the macrophage response and promote a surrounding anti-inflammatory microenvironment ready for injection for wound healing applications.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Colágeno/farmacología , Factores Inmunológicos/farmacología , Macrófagos/efectos de los fármacos , Dióxido de Silicio/química , Uretano/química , Animales , Antiinflamatorios no Esteroideos/química , Colágeno/química , Sistemas de Liberación de Medicamentos , Geles/química , Factores Inmunológicos/química , Inflamación/tratamiento farmacológico , Inflamación/patología , Ratones , Células RAW 264.7 , Cicatrización de Heridas/efectos de los fármacos
10.
Parasitology ; 146(13): 1636-1645, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31391128

RESUMEN

Trichomonas vaginalis is an extracellular parasite that colonizes the human urogenital tract leading to trichomoniasis, the most common sexually-transmitted non-viral disease worldwide. The immune response plays a critical role in the host defense against this parasite. Trichomonas' DNA contains unmethylated CpG motifs (CpGDNA) that in other microorganisms act as modulators of the immune response. However, the molecular mechanisms responsible for CpGDNA immune modulation are still unclear. As macrophages participate in the first line of defense against infection, we investigated the type of immune response of murine macrophages to T. vaginalis DNA (TvDNA). We observed high expression of the proinflammatory cytokines IL-6 and IL-12p40 in macrophages stimulated with TvDNA. In contrast, the anti-inflammatory response, assessed by IL-10 and IL-13 mRNA expression was delayed. This suggests that the immune response induced by TvDNA is modulated through cytokine production, mediated partly by NADPH-oxidase activity, as TvDNA induced reactive species of oxygen production and a rounded morphology in macrophages indicative of an M1 phenotype. Furthermore, infected mice pretreated with TvDNA displayed persistent vulvar inflammation and decreased parasite viability consistent with higher proinflammatory cytokine levels during infection compared to untreated mice. Overall, our findings suggest that TvDNA pretreatment modulates the immune response favouring parasite elimination.


Asunto(s)
Citocinas/inmunología , ADN Protozoario/administración & dosificación , Macrófagos/parasitología , Trichomonas vaginalis/fisiología , Animales , Islas de CpG , Femenino , Inmunomodulación , Inflamación , Macrófagos/inmunología , Ratones , Ratones Endogámicos BALB C , NADPH Oxidasas/metabolismo , Células RAW 264.7 , Especies Reactivas de Oxígeno/metabolismo , Vulva/inmunología , Vulva/fisiopatología
11.
Nat Commun ; 10(1): 2393, 2019 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-31160557

RESUMEN

Bacterial ClpB and yeast Hsp104 are homologous Hsp100 protein disaggregases that serve critical functions in proteostasis by solubilizing protein aggregates. Two AAA+ nucleotide binding domains (NBDs) power polypeptide translocation through a central channel comprised of a hexameric spiral of protomers that contact substrate via conserved pore-loop interactions. Here we report cryo-EM structures of a hyperactive ClpB variant bound to the model substrate, casein in the presence of slowly hydrolysable ATPγS, which reveal the translocation mechanism. Distinct substrate-gripping interactions are identified for NBD1 and NBD2 pore loops. A trimer of N-terminal domains define a channel entrance that binds the polypeptide substrate adjacent to the topmost NBD1 contact. NBD conformations at the seam interface reveal how ATP hydrolysis-driven substrate disengagement and re-binding are precisely tuned to drive a directional, stepwise translocation cycle.


Asunto(s)
Adenosina Trifosfato/análogos & derivados , Caseínas/metabolismo , Endopeptidasa Clp/ultraestructura , Proteínas de Escherichia coli/ultraestructura , Escherichia coli/metabolismo , Proteínas de Choque Térmico/ultraestructura , Transporte de Proteínas , Dominio AAA , Adenosina Trifosfato/metabolismo , Microscopía por Crioelectrón , Endopeptidasa Clp/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de Choque Térmico/metabolismo , Hidrólisis , Modelos Moleculares , Péptidos/metabolismo , Agregado de Proteínas , Subunidades de Proteína/metabolismo
12.
Biophys J ; 116(10): 1856-1872, 2019 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-31027887

RESUMEN

Heat shock protein (Hsp) 104 is a hexameric ATPases associated with diverse cellular activities motor protein that enables cells to survive extreme stress. Hsp104 couples the energy of ATP binding and hydrolysis to solubilize proteins trapped in aggregated structures. The mechanism by which Hsp104 disaggregates proteins is not completely understood but may require Hsp104 to partially or completely translocate polypeptides across its central channel. Here, we apply transient state, single turnover kinetics to investigate the ATP-dependent translocation of soluble polypeptides by Hsp104 and Hsp104A503S, a potentiated variant developed to resolve misfolded conformers implicated in neurodegenerative disease. We establish that Hsp104 and Hsp104A503S can operate as nonprocessive translocases for soluble substrates, indicating a "partial threading" model of translocation. Remarkably, Hsp104A503S exhibits altered coupling of ATP binding to translocation and decelerated dissociation from polypeptide substrate compared to Hsp104. This altered coupling and prolonged substrate interaction likely increases entropic pulling forces, thereby enabling more effective aggregate dissolution by Hsp104A503S.


Asunto(s)
Proteínas de Choque Térmico/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Adenosina Trifosfato/metabolismo , Secuencia de Aminoácidos , Proteínas de Choque Térmico/genética , Hidrólisis , Cinética , Proteínas Mutantes/metabolismo , Péptidos/metabolismo , Agregado de Proteínas , Unión Proteica , Conformación Proteica , Pliegue de Proteína , Proteínas de Saccharomyces cerevisiae/genética , Relación Estructura-Actividad
13.
Structure ; 27(3): 449-463.e7, 2019 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-30595457

RESUMEN

Hsp104 is an AAA+ protein disaggregase with powerful amyloid-remodeling activity. All nonmetazoan eukaryotes express Hsp104 while eubacteria express an Hsp104 ortholog, ClpB. However, most studies have focused on Hsp104 from Saccharomyces cerevisiae and ClpB orthologs from two eubacterial species. Thus, the natural spectrum of Hsp104/ClpB molecular architectures and protein-remodeling activities remains largely unexplored. Here, we report two structures of Hsp104 from the thermophilic fungus Calcarisporiella thermophila (CtHsp104), a 2.70Å crystal structure and 4.0Å cryo-electron microscopy structure. Both structures reveal left-handed, helical assemblies with all domains clearly resolved. We thus provide the highest resolution and most complete view of Hsp104 hexamers to date. We also establish that CtHsp104 antagonizes several toxic protein-misfolding events in vivo where S. cerevisiae Hsp104 is ineffective, including rescue of TDP-43, polyglutamine, and α-synuclein toxicity. We suggest that natural Hsp104 variation is an invaluable, untapped resource for illuminating therapeutic disaggregases for fatal neurodegenerative diseases.


Asunto(s)
Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/farmacología , Mucorales/enzimología , Microscopía por Crioelectrón , Cristalografía por Rayos X , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas Fúngicas/química , Proteínas Fúngicas/farmacología , Humanos , Modelos Moleculares , Péptidos/antagonistas & inhibidores , Conformación Proteica en Hélice alfa , Deficiencias en la Proteostasis/prevención & control , alfa-Sinucleína/antagonistas & inhibidores
14.
J Biomater Appl ; 33(7): 903-914, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30526211

RESUMEN

The stability and bioactivity of biologic implants rely mainly on the control of the crosslinking process of collagen. However, the most common methods have no control on the crosslinking degree producing it excessively. This study outlines the role of crosslinking of collagen-based implants with oligourethane on the host response following reconstruction of a rat full-thickness abdominal wall defect. We decellularized and crosslinked bovine pericardial tissue to achieve two crosslinking degrees. For the decellularized implants, named as non-crosslinked (N-CL), the collagen-amines were 0.42 ± 0.02 mmol/mg. Crosslinking by the oligourethane reduced the primary amine concentration to 0.28 ± 0.01 and 0.19 ± 0.01 mmol/mg; these values were classified as low (∼30%, L-CL) and medium crosslinking (∼50%, M-CL), respectively. By imaging the implants using second harmonic generation microscopy, we observed undulated bundles of collagen fibers organized in multi-directed layers localized in N-CL and L-CL samples. Post-implantation, a negligible change in the organization of collagen fibers in the crosslinked implants was observed, suggesting that the in vivo biodegradation was delayed. An enlargement of the implant area was also observed, without rupture, in all three (N-CL, L-CL, M-CL) materials, whereas adhesion to the omentum, but not to the bowel, was observed. The number of blood vessels after 90-day implantation in N-CL and L-CL was 13 ± 1 and 12 ± 1 per field, respectively, while the number significantly decreased to 2 ± 1 in M-CL. The results suggest that the controlled degree of crosslinking in oligourethane-modified biologic implants can be used as a strategy to balance biodegradation and remodeling in surgical repair of soft tissues.


Asunto(s)
Pared Abdominal/cirugía , Materiales Biocompatibles/química , Colágeno/química , Reactivos de Enlaces Cruzados/química , Pericardio/química , Uretano/química , Pared Abdominal/patología , Animales , Bioprótesis , Bovinos , Masculino , Pericardio/trasplante , Pericardio/ultraestructura , Ratas , Ratas Wistar , Procedimientos de Cirugía Plástica , Resistencia a la Tracción
15.
Macromol Biosci ; 18(9): e1800099, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29943462

RESUMEN

The polarization of macrophages M0 to M1 or M2 using molecules embedded in matrices and hydrogels is an active field of study. The design of biomaterials capable of promoting polarization has become a paramount need nowadays, since in the healing process macrophages M1 and M2 modulate the inflammatory response. In this work, several immunocytochemistry and ELISA tests strongly suggest the achievement of polarization using collagen-based membranes crosslinked with tri-functionalized oligourethanes and coated with silica. Measuring the amount of TGF-ß1 secreted to culture media by macrophages growth on these materials, and quantifying the macrophage morphology, it is proved that it is possible to stimulate the anti-inflammatory pathway toward M2, having measurements with p ≤ 0.05 of statistical significance between the control and the collagen-based membranes. Furthermore, some physicochemical characteristics of the hybrid materials are tested envisaging future applications: collagenase degradation resistance, water uptake, collagen fiber diameter, and deformation resistance are increased for all the crosslinked biomaterials. It is considered that the biological and physicochemical properties make the material suitable for the modulation of the inflammatory response in the chronic wounds and promising for in vivo studies.


Asunto(s)
Materiales Biocompatibles/química , Colágeno/química , Inflamación/patología , Macrófagos/metabolismo , Membranas Artificiales , Animales , Polaridad Celular , Reactivos de Enlaces Cruzados/química , Citocinas/metabolismo , Isocianatos/química , Lisina/análogos & derivados , Lisina/química , Macrófagos/patología , Ratones , Poliuretanos/síntesis química , Poliuretanos/química , Células RAW 264.7 , Ratas Wistar , Dióxido de Silicio/química
16.
Minerva Ginecol ; 70(1): 53-57, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28994558

RESUMEN

BACKGROUND: The advent of flexible CO2 laser fiber to gynecology arena might represent a turning point in the use of laser energy on a large-scale basis in gynecological surgery. However, there might be some concerns regarding the degree of surgical skills required to use the flexible system. The purpose of our study is to evaluate whether flexible CO2 laser fiber is technically accessible. METHODS: Fourteen residents in Obstetrics and Gynecology without surgical experience attending laparoscopic box training with both flexible CO2 laser fiber and traditional line-of-sight CO2 laser using Lumenis AcuPulse Duo CO2 laser (Lumenis, Yokne'am Illit, Israel) were prospectively enrolled. Participants were tested at sequential time points on specific surgical tasks and results obtained with the flexible CO2 laser fiber and the traditional line-of-sight CO2 laser were compared. Results were compared by means of paired t-test and a two-tailed P value <0.05 was considered significant. RESULTS: Mean grading at the beginning of training were similar between flexible fiber and line-of-sight CO2 laser. At the end of training, significant improvement in surgical skills was obtained for both techniques, with a statistically significant higher grading for flexible fiber CO2 laser compared to line-of-sight CO2 laser. CONCLUSIONS: Our study found that residents without surgical experience show better skills with the flexible CO2 laser fiber delivery system compared to the standard line-of-sight CO2 laser system after a two-month training period with gynecological laparoscopic box. According to our results, flexible CO2 laser fiber delivery system is technically accessible and holds a potential in gynecological surgery.


Asunto(s)
Procedimientos Quirúrgicos Ginecológicos/educación , Ginecología/educación , Laparoscopía/educación , Láseres de Gas/uso terapéutico , Adulto , Competencia Clínica , Evaluación Educacional , Procedimientos Quirúrgicos Ginecológicos/métodos , Ginecología/métodos , Humanos , Internado y Residencia , Laparoscopía/métodos , Curva de Aprendizaje , Estudios Prospectivos
17.
Mater Sci Eng C Mater Biol Appl ; 79: 793-801, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-28629082

RESUMEN

In this work, hydrolysates of extracellular matrix (hECM) were obtained from rat tail tendon (TR), bovine Achilles tendon (TAB), porcine small intestinal submucosa (SIS) and bovine pericardium (PB), and they were polymerized to generate ECM hydrogels. The composition of hECM was evaluated by quantifying the content of sulphated glycosaminoglycans (sGAG), fibronectin and laminin. The polymerization process, structure, physicochemical properties, in vitro degradation and biocompatibility were studied and related to their composition. The results indicated that the hECM derived from SIS and PB were significantly richer in sGAG, fibronectin and laminin, than those derived from TAB and TR. These differences in hECM composition influenced the polymerization and the structural characteristics of the fibrillar gel network. Consequently, the swelling, mechanics and degradation of the hydrogels showed a direct relationship with the remaining composition. Moreover, the cytocompatibility and the secretion of transforming growth factor beta-1 (TGF-ß1) by macrophages were enhanced in hydrogels with the highest residual content of ECM biomolecules. The results of this work evidenced the role of the ECM molecules remaining after both decellularization and hydrolysis steps to produce tissue derived hydrogels with structure and properties tailored to enhance their performance in tissue engineering and regenerative medicine applications.


Asunto(s)
Hidrogeles/química , Animales , Bovinos , Matriz Extracelular , Glicosaminoglicanos , Humanos , Laminina , Ratas , Ingeniería de Tejidos
18.
J Biomed Mater Res A ; 104(11): 2810-22, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27387409

RESUMEN

The extracellular matrix molecules remaining in bioscaffolds derived from decellularized xenogeneic tissues appear to be important for inducing cell functions conducting tissue regeneration. Here, we studied whether decellularization methods, that is, detergent Triton X-100 (TX) alone and TX combined with reversible alkaline swelling (STX), applied to bovine pericardial tissue, could affect the bioscaffold components. The in vitro macrophage response, subdermal biodegradation, and cell infiltration were also studied. The results indicate a lower leaching of fibronectin, but a higher leaching of laminin and sulfated glycosaminoglycans from tissues decellularized with STX and TX, respectively. The in vitro secretion of interleukin-6 and monocyte chemoattractant protein by RAW264.7 macrophages is promoted by decellularized bioscaffold leachates. A lower polymorphonuclear cell density is observed around decellularized bioscaffolds at 1-day implantation; concurrently showing a higher cell infiltration in STX- than in TX-implant. Cells infiltrated into TX-implant show a fibroblastic morphology at 7-day implantation, concurrently the capillary formation is observed at 14-day. Pericardial bioscaffolds suffer biodegradation more pronounced in STX- than in TX-implant. Both TX and STX decellularization methods favor a high leaching of basal lamina components, which presumably promotes a faster macrophage stimulation compared to nondecellularized tissue, and appear to be associated with an increased host cell infiltration in a rat subdermal implantation. Meanwhile, the connective tissue components leaching from TX decellularized bioscaffolds, unlike the STX ones, appear to be associated with an enhanced angiogenesis accompanied by an early-promoted fibroblastic cell transition. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2810-2822, 2016.


Asunto(s)
Bioprótesis , Macrófagos/inmunología , Pericardio/química , Pericardio/citología , Andamios del Tejido/química , Animales , Bioprótesis/efectos adversos , Bovinos , Citocinas/análisis , Citocinas/inmunología , Detergentes/química , Macrófagos/citología , Ratones , Pericardio/inmunología , Células RAW 264.7 , Ratas Wistar , Ingeniería de Tejidos , Andamios del Tejido/efectos adversos
19.
Biomed Mater ; 11(3): 035016, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27305317

RESUMEN

This paper reports a new method to modify hydrogels derived from the acellular extracellular matrix (ECM) and consequently to improve their properties. The method is comprised of the combination of liquid precursors derived from hydrolyzed acellular small intestinal submucosa (hECM) and water-soluble oligourethanes that bear protected isocyanate groups, synthesized from poly(ethylene glycol) (PEG) and hexamethylene diisocyanate (HDI). The results demonstrate that the reactivity of oligourethanes, along with their water solubility, properly induce simultaneously the polymerization of type I collagen and its crosslinking. The polymerization rate and the gel network parameters such as fiber diameter, porosity, crosslinking degree, mechanics, swelling, in vitro degradation and cell proliferation, keep a direct relationship with the oligourethane concentration. Consequently, the hybrid hydrogels formulated with 15 wt.% of oligourethane exhibit enhanced storage modulus and degradation resistance, while maintaining the cell viability and impeding the fibroblast-induced contraction in comparison with the hECM hydrogels without oligourethanes. Therefore, this method is adequate to prepare novel hydrogels where the adjustment of the crosslinking degree controls the materials structure and their properties. This new method offers advantages for regulating the features of ECM-derived templates, thereby extending their possibilities for tissue engineering (TE) applications.


Asunto(s)
Matriz Extracelular/química , Hidrogeles/química , Uretano/química , Animales , Proliferación Celular , Colágeno/química , Fibroblastos/efectos de los fármacos , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Isocianatos/química , Macrófagos/metabolismo , Ratones , Ninhidrina/química , Polietilenglicoles/química , Reología , Ingeniería de Tejidos
20.
Contemp Clin Trials Commun ; 4: 46-51, 2016 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-29736469

RESUMEN

Preclinical studies and small clinical trials suggest that glucagon-like peptide 1 (GLP1) may have a positive effect on ventricular function. Liraglutide is a GLP1-analogue used in the treatment of type 2 diabetes. LIPER2 is a phase IV, randomised, double-blind, placebo-controlled, parallel-design trial, assessing the effect of 6 months' liraglutide 1.8 mg/d on measures of cardiac function and physical performance in patients with type 2 diabetes. A total of 30 patients with type 2 diabetes will be included, if their HbA1c is between 7 and 10% while on oral agents (including metformin if tolerated and not contraindicated), a maximum of 2 intermediate or long-acting insulin injections per day or a combination of both. After their baseline examinations, patients are randomised to receive a daily subcutaneous liraglutide or placebo injection (titrated to 1.8 mg/d if tolerated) for 6 months. The primary end-point is the maximal oxygen consumption during cycle ergometry at the end of the study period. Other end-points include distance covered during a 6-min walk test, left ventricular ejection fraction and other measures of ventricular systolic and diastolic functions assessed by echocardiography, heart rate, blood pressure, pro-brain natriuretic peptide, C-reactive protein, HbA1c, lipids, apolipoprotein B, body weight and waist girth. Safety end-points include adverse event reporting, blood count, kidney and liver function, amylase, lipase, electrolytes, calcitonin, CA19.9 and pregnancy test for fertile women. At the time of this report, recruitment is still ongoing. Results are expected to be reported in December 2016.

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