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1.
Int J Mol Sci ; 25(18)2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39337509

RESUMO

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.


Assuntos
Linfócitos T CD4-Positivos , Mucosa Intestinal , Receptores CCR , Receptores de Dopamina D5 , Transdução de Sinais , Receptores CCR/metabolismo , Receptores CCR/genética , Humanos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/imunologia , Receptores de Dopamina D5/metabolismo , Receptores de Dopamina D5/genética , Mucosa Intestinal/metabolismo , Colo/metabolismo , Movimento Celular , Dopamina/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Doenças Inflamatórias Intestinais/imunologia
2.
Mol Divers ; 27(5): 2073-2092, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36306047

RESUMO

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.


Assuntos
Antiprotozoários , Chalconas , Leishmaniose , Humanos , Chalconas/química , Succinato Desidrogenase , Éteres , Antiprotozoários/química , Leishmaniose/tratamento farmacológico , Relação Estrutura-Atividade
3.
Int J Mol Sci ; 24(21)2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37958952

RESUMO

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.


Assuntos
Praguicidas , Humanos , Praguicidas/toxicidade , Biodegradação Ambiental , Bactérias/metabolismo , Fungos/metabolismo , Agricultura
4.
Sensors (Basel) ; 21(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805351

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-31936493

RESUMO

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+.


Assuntos
Escherichia coli/metabolismo , Expressão Gênica , Peroxidases/isolamento & purificação , Phanerochaete/enzimologia , Sequência de Aminoácidos , Ensaios Enzimáticos , Vetores Genéticos/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Padrões de Referência , Solubilidade
6.
J Neuroinflammation ; 16(1): 258, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31810491

RESUMO

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.


Assuntos
Astrócitos/metabolismo , Mediadores da Inflamação/metabolismo , Microglia/metabolismo , Receptores de Dopamina D3/metabolismo , Transdução de Sinais/fisiologia , Animais , Astrócitos/efeitos dos fármacos , Células Cultivadas , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/efeitos dos fármacos , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/genética , Transtornos Parkinsonianos/metabolismo , Receptores de Dopamina D3/antagonistas & inibidores , Receptores de Dopamina D3/genética , Transdução de Sinais/efeitos dos fármacos
8.
J Cardiothorac Vasc Anesth ; 33(2): 433-439, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30190202

RESUMO

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.


Assuntos
Manuseio das Vias Aéreas/métodos , Obstrução das Vias Respiratórias/terapia , Ventilação Monopulmonar/métodos , Complicações Pós-Operatórias/prevenção & controle , Guias de Prática Clínica como Assunto , Procedimentos Cirúrgicos Torácicos/métodos , Traqueostomia/métodos , Obstrução das Vias Respiratórias/diagnóstico , Broncoscopia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
9.
Anesth Analg ; 126(6): 1968-1978, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29189274

RESUMO

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.


Assuntos
Manuseio das Vias Aéreas/métodos , Intubação Intratraqueal/métodos , Pulmão/diagnóstico por imagem , Ventilação Monopulmonar/métodos , Traqueia/diagnóstico por imagem , Manuseio das Vias Aéreas/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Tecnologia de Fibra Óptica/métodos , Humanos , Intubação Intratraqueal/instrumentação , Ventilação Monopulmonar/instrumentação
18.
Anesth Analg ; 123(5): 1297-1301, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27607479

RESUMO

BACKGROUND: In order to provide guidance to organizations considering elective weekend surgical case scheduling, we analyzed data from the American Society of Anesthesiologist's Anesthesia Quality Institute. We determined the US anesthesia workload on Saturdays and Sundays. METHODS: The American Society of Anesthesiologist's Anesthesia Quality Institute data were from all US anesthesia groups that submitted cases to the National Anesthesia Clinical Outcomes Registry for 2013. For each of the N = 2,075,188 cases, we identified the local date and time of the start of anesthesia care and the duration of anesthesia care. Anesthesia workload was measured as the time from the start to the end of continuous anesthesia care. Because elective cases are rarely scheduled on Sundays, we considered the difference in workload between Saturday and Sunday to estimate elective case scheduling. This difference would be an overestimate if some patients' scheduled cases were postponed from Friday to Saturday. Data are reported as mean ± standard error; N = 13 four-week periods. RESULTS: The difference in the anesthesia minutes between Saturdays versus Sundays 7:00 AM to 2:59 PM (ie, elective caseload) represented just 0.38% ± 0.02% of the total minutes nationwide; Saturday 1.57% ± 0.03% versus Sunday 1.19% ± 0.02%. The P < .00001 comparing the 0.38% with 1.0% and, also, with 0.5% (upper 99% confidence interval = 0.42%). CONCLUSIONS: The imputed Saturday elective schedule represents a tiny percentage of overall anesthetic workload nationwide. Saturday elective surgery is currently an uncommon practice in the United States. Based on this prior knowledge, organizations considering changes to their current scheduling strategies should perform a thorough statistical analysis of their local workload prior to implementation and apply evidence-based criteria to guide their decision-making process.


Assuntos
Anestesia , Agendamento de Consultas , Procedimentos Cirúrgicos Eletivos , Admissão e Escalonamento de Pessoal , Carga de Trabalho , Anestesia/estatística & dados numéricos , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Humanos , Admissão e Escalonamento de Pessoal/estatística & dados numéricos , Sistema de Registros , Estados Unidos , Carga de Trabalho/estatística & dados numéricos
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