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1.
Int J Mol Sci ; 25(18)2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39337509

RESUMEN

Inflammatory bowel diseases (IBDs) involve chronic inflammation of the gastrointestinal tract, where effector CD4+ T-cells play a central role. Thereby, the recruitment of T-cells into the colonic mucosa represents a key process in IBD. We recently found that CCR9 and DRD5 might form a heteromeric complex on the T-cell surface. The increase in CCL25 production and the reduction in dopamine levels associated with colonic inflammation represent a dual signal stimulating the CCR9:DRD5 heteromer, which promotes the recruitment of CD4+ T-cells into the colonic lamina propria. Here, we aimed to analyse the molecular requirements involved in the heteromer assembly as well as to determine the underlying cellular mechanisms involved in the colonic tropism given by the stimulation of the CCR9:DRD5 complex. The results show that dual stimulation of the CCR9:DRD5 heteromer potentiates the phosphorylation of the myosin light chain 2 (MLC2) and the migration speed in confined microchannels. Accordingly, disrupting the CCR9:DRD5 assembly induced a sharp reduction in the pMLC2 in vitro, decreased the migratory speed in confined microchannels, and dampened the recruitment of CD4+ T-cells into the inflamed colonic mucosa. Furthermore, in silico analysis confirmed that the interface of interaction of CCR9:DRD5 is formed by the transmembrane segments 5 and 6 from each protomer. Our findings demonstrated that the CCR9:DRD5 heteromeric complex plays a fundamental role in the migration of CD4+ T-cells into the colonic mucosa upon inflammation. Thereby, the present study encourages the design of strategies for disassembling the formation of the CCR9:DRD5 as a therapeutic opportunity to treat IBD.


Asunto(s)
Linfocitos T CD4-Positivos , Mucosa Intestinal , Receptores CCR , Receptores de Dopamina D5 , Transducción de Señal , Receptores CCR/metabolismo , Receptores CCR/genética , Humanos , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/inmunología , Receptores de Dopamina D5/metabolismo , Receptores de Dopamina D5/genética , Mucosa Intestinal/metabolismo , Colon/metabolismo , Movimiento Celular , Dopamina/metabolismo , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/patología , Enfermedades Inflamatorias del Intestino/inmunología
2.
Mol Divers ; 27(5): 2073-2092, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36306047

RESUMEN

Drug therapy for leishmaniasis remains a major challenge as currently available drugs have limited efficacy, induce serious side-effects and are not accessible to everyone. Thus, the discovery of affordable drugs is urgently needed. Chalcones present a great potential as bioactive agents due to simple structure and functionalization capacity. The antileishmanial activity of different natural and synthetic chalcones have been reported. Here we report the synthesis of twenty-five novel prenylated chalcones that displayed antiparasitic activity in Leishmania mexicana. All the chalcones were evaluated at 5 µg/mL and eleven compounds exhibited a metabolic inhibition close to or exceeding 50%. Compounds 49, 30 and 55 were the three most active with IC50 values < 10 µM. These chalcones also showed the highest selectivity index (SI) values. Interestingly 49 and 55 possessing a substituent at a meta position in the B ring suggests that the substitution pattern influences antileishmanial activity. Additionally, a tridimensional model of fumarate reductase of L. mexicana was obtained by homology modeling. Docking studies suggest that prenylated chalcones could modulate fumarate reductase activity by binding with good affinity to two binding sites that are critical for the target. In conclusion, the novel prenylated chalcones could be considered as promising antileishmanial agents.


Asunto(s)
Antiprotozoarios , Chalconas , Leishmaniasis , Humanos , Chalconas/química , Succinato Deshidrogenasa , Éteres , Antiprotozoarios/química , Leishmaniasis/tratamiento farmacológico , Relación Estructura-Actividad
3.
Int J Mol Sci ; 24(21)2023 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-37958952

RESUMEN

Pesticides are chemicals used in agriculture, forestry, and, to some extent, public health. As effective as they can be, due to the limited biodegradability and toxicity of some of them, they can also have negative environmental and health impacts. Pesticide biodegradation is important because it can help mitigate the negative effects of pesticides. Many types of microorganisms, including bacteria, fungi, and algae, can degrade pesticides; microorganisms are able to bioremediate pesticides using diverse metabolic pathways where enzymatic degradation plays a crucial role in achieving chemical transformation of the pesticides. The growing concern about the environmental and health impacts of pesticides is pushing the industry of these products to develop more sustainable alternatives, such as high biodegradable chemicals. The degradative properties of microorganisms could be fully exploited using the advances in genetic engineering and biotechnology, paving the way for more effective bioremediation strategies, new technologies, and novel applications. The purpose of the current review is to discuss the microorganisms that have demonstrated their capacity to degrade pesticides and those categorized by the World Health Organization as important for the impact they may have on human health. A comprehensive list of microorganisms is presented, and some metabolic pathways and enzymes for pesticide degradation and the genetics behind this process are discussed. Due to the high number of microorganisms known to be capable of degrading pesticides and the low number of metabolic pathways that are fully described for this purpose, more research must be conducted in this field, and more enzymes and genes are yet to be discovered with the possibility of finding more efficient metabolic pathways for pesticide biodegradation.


Asunto(s)
Plaguicidas , Humanos , Plaguicidas/toxicidad , Biodegradación Ambiental , Bacterias/metabolismo , Hongos/metabolismo , Agricultura
4.
Sensors (Basel) ; 21(7)2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33805351

RESUMEN

Canopy characterisation is a key factor for the success and efficiency of the pesticide application process in vineyards. Canopy measurements to determine the optimal volume rate are currently conducted manually, which is time-consuming and limits the adoption of precise methods for volume rate selection. Therefore, automated methods for canopy characterisation must be established using a rapid and reliable technology capable of providing precise information about crop structure. This research providedregression models for obtaining canopy characteristics of vineyards from unmanned aerial vehicle (UAV) and satellite images collected in three significant growth stages. Between 2018 and 2019, a total of 1400 vines were characterised manually and remotely using a UAV and a satellite-based technology. The information collected from the sampled vines was analysed by two different procedures. First, a linear relationship between the manual and remote sensing data was investigated considering every single vine as a data point. Second, the vines were clustered based on three vigour levels in the parcel, and regression models were fitted to the average values of the ground-based and remote sensing-estimated canopy parameters. Remote sensing could detect the changes in canopy characteristics associated with vegetation growth. The combination of normalised differential vegetation index (NDVI) and projected area extracted from the UAV images is correlated with the tree row volume (TRV) when raw point data were used. This relationship was improved and extended to canopy height, width, leaf wall area, and TRV when the data were clustered. Similarly, satellite-based NDVI yielded moderate coefficients of determination for canopy width with raw point data, and for canopy width, height, and TRV when the vines were clustered according to the vigour. The proposed approach should facilitate the estimation of canopy characteristics in each area of a field using a cost-effective, simple, and reliable technology, allowing variable rate application in vineyards.

5.
Int J Mol Sci ; 21(2)2020 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-31936493

RESUMEN

Manganese peroxidases (MnP) from the white-rot fungi Phanerochaete chrysosporium catalyse the oxidation of Mn2+ to Mn3+, a strong oxidizer able to oxidize a wide variety of organic compounds. Different approaches have been used to unravel the enzymatic properties and potential applications of MnP. However, these efforts have been hampered by the limited production of native MnP by fungi. Heterologous expression of MnP has been achieved in both eukaryotic and prokaryotic expression systems, although with limited production and many disadvantages in the process. Here we described a novel molecular approach for the expression and purification of manganese peroxidase isoform 1 (MnP1) from P. chrysosporium using an E. coli-expression system. The proposed strategy involved the codon optimization and chemical synthesis of the MnP1 gene for optimised expression in the E. coli T7 shuffle host. Recombinant MnP1 (rMnP1) was expressed as a fusion protein, which was recovered from solubilised inclusion bodies. rMnP1 was purified from the fusion protein using intein-based protein purification techniques and a one-step affinity chromatography. The designated strategy allowed production of an active enzyme able to oxidize guaiacol or Mn2+.


Asunto(s)
Escherichia coli/metabolismo , Expresión Génica , Peroxidasas/aislamiento & purificación , Phanerochaete/enzimología , Secuencia de Aminoácidos , Pruebas de Enzimas , Vectores Genéticos/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Estándares de Referencia , Solubilidad
6.
J Neuroinflammation ; 16(1): 258, 2019 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-31810491

RESUMEN

BACKGROUND: Neuroinflammation constitutes a pathogenic process leading to neurodegeneration in several disorders, including Alzheimer's disease, Parkinson's disease (PD) and sepsis. Despite microglial cells being the central players in neuroinflammation, astrocytes play a key regulatory role in this process. Our previous results indicated that pharmacologic-antagonism or genetic deficiency of dopamine receptor D3 (DRD3) attenuated neuroinflammation and neurodegeneration in two mouse models of PD. Here, we studied how DRD3-signalling affects the dynamic of activation of microglia and astrocyte in the context of systemic inflammation. METHODS: Neuroinflammation was induced by intraperitoneal administration of LPS. The effect of genetic DRD3-deficiency or pharmacologic DRD3-antagonism in the functional phenotype of astrocytes and microglia was determined by immunohistochemistry and flow cytometry at different time-points. RESULTS: Our results show that DRD3 was expressed in astrocytes, but not in microglial cells. DRD3 deficiency resulted in unresponsiveness of astrocytes and in attenuated microglial activation upon systemic inflammation. Furthermore, similar alterations in the functional phenotypes of glial cells were observed by DRD3 antagonism and genetic deficiency of DRD3 upon LPS challenge. Mechanistic analyses show that DRD3 deficiency resulted in exacerbated expression of the anti-inflammatory protein Fizz1 in glial cells both in vitro and in vivo. CONCLUSIONS: These results suggest that DRD3 signalling regulates the dynamic of the acquisition of pro-inflammatory and anti-inflammatory features by astrocytes and microglia, finally favouring microglial activation and promoting neuroinflammation.


Asunto(s)
Astrocitos/metabolismo , Mediadores de Inflamación/metabolismo , Microglía/metabolismo , Receptores de Dopamina D3/metabolismo , Transducción de Señal/fisiología , Animales , Astrocitos/efectos de los fármacos , Células Cultivadas , Inflamación/inducido químicamente , Inflamación/genética , Inflamación/metabolismo , Lipopolisacáridos/toxicidad , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microglía/efectos de los fármacos , Trastornos Parkinsonianos/inducido químicamente , Trastornos Parkinsonianos/genética , Trastornos Parkinsonianos/metabolismo , Receptores de Dopamina D3/antagonistas & inhibidores , Receptores de Dopamina D3/genética , Transducción de Señal/efectos de los fármacos
8.
J Cardiothorac Vasc Anesth ; 33(2): 433-439, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30190202

RESUMEN

OBJECTIVES: Lung isolation techniques are designed to facilitate surgical exposure in thoracic surgical patients and provide one-lung ventilation (OLV). Some patients have a tracheostomy in situ, which makes the management of the airway and OLV difficult. The objective of this retrospective study was to review cases that had a tracheostomy prior to thoracic surgery and evaluate the clinical use and efficiency with the airway management and lung isolation devices. DESIGN: This was a retrospective data analysis. SETTING: Tertiary care university hospital. INTERVENTIONS: After institutional review board approval, the authors reviewed 3,225 charts of patients who had thoracic surgery involving OLV. Seventy patients were identified who had tracheostomy in situ. Each case was reviewed regarding airway management and lung isolation technique. MEASUREMENTS AND MAIN RESULTS: The authors identified 70 patients who had a tracheostomy in situ. The cases were divided into 2 groups: a fresh tracheostomy stoma <7 days (n = 6) or long-term stoma >7 days (n = 64). The authors collected information regarding the devices used to manage the airway and lung isolation techniques. The devices used to manage the airway include the Shiley cuffed low pressure tracheostomy tube, single-lumen endotracheal tube (SLT), or double-lumen endotracheal tube (DLT). Devices used to manage OLV included SLTs, with or without bronchial blockers, or DLTs. Flexible fiberoptic bronchoscopy was used to assess the airway and confirm the position of the lung isolation device. Six cases had an early-stage fresh tracheostomy stoma where the Shiley tracheostomy tube was used for ventilation followed by the use of a bronchial blocker. In contrast, for the patients who had a long-term stoma, the following devices were used: (1) a SLT plus a bronchial blocker in 38 cases, a Shiley tracheostomy tube plus bronchial blocker in 15 cases, use of a SLT guided into a selective bronchus in 7 cases, and use of a DLT in 4 cases. In all cases, flexible fiberoptic bronchoscopy was used and no complications occurred secondary to airway management or OLV. CONCLUSION: In patients undergoing thoracic surgery and OLV, and with a fresh tracheostomy stoma in situ, the authors recommend the use of the Shiley tracheostomy tube plus a bronchial blocker. In patients with a long-term tracheostomy stoma, a SLT can be used selectively to intubate 1 bronchus. In addition, an SLT or a Shiley tube can be used in conjunction with an independent bronchial blocker, such as the Arndt wire-guided bronchial blocker, Cohen tip-deflecting blocker, Fuji Uniblocker, or EZ-Blocker. DLTs are the least frequently used device for OLV in tracheostomized patients.


Asunto(s)
Manejo de la Vía Aérea/métodos , Obstrucción de las Vías Aéreas/terapia , Ventilación Unipulmonar/métodos , Complicaciones Posoperatorias/prevención & control , Guías de Práctica Clínica como Asunto , Procedimientos Quirúrgicos Torácicos/métodos , Traqueostomía/métodos , Obstrucción de las Vías Aéreas/diagnóstico , Broncoscopía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo
9.
Anesth Analg ; 126(6): 1968-1978, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29189274

RESUMEN

One-lung ventilation is routinely used to facilitate exposure for thoracic surgical procedures and can be achieved via several lung isolation techniques. The optimal method for lung isolation depends on a number of factors that include (1) the indication for lung isolation, (2) anatomic features of the upper and lower airway, (3) availability of equipment and devices, and (4) the anesthesiologist's proficiency and preferences. Though double-lumen endobronchial tubes (DLTs) are most commonly utilized to achieve lung isolation, the use of endobronchial blockers offer advantages in patients with challenging airway anatomy. Anesthesiologists should be familiar with existing alternatives to the DLT for lung isolation and alternative techniques for DLT placement in the patient with a difficult airway. Newer technologies such as videolaryngoscopy with or without adjunctive fiberoptic bronchoscopy may facilitate intubation and lung isolation in difficult airway management.


Asunto(s)
Manejo de la Vía Aérea/métodos , Intubación Intratraqueal/métodos , Pulmón/diagnóstico por imagen , Ventilación Unipulmonar/métodos , Tráquea/diagnóstico por imagen , Manejo de la Vía Aérea/instrumentación , Tecnología de Fibra Óptica/instrumentación , Tecnología de Fibra Óptica/métodos , Humanos , Intubación Intratraqueal/instrumentación , Ventilación Unipulmonar/instrumentación
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