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1.
J Anat ; 244(6): 887-899, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38243145

RESUMO

Oculomotricity is a multidimensional domain characterised by a delicate interplay of anatomical structures and physiological processes. This manuscript meticulously dissects the nuances of this interplay, bringing to the fore the integral role of the extraocular muscles (EOMs) and their intricate relationship with the myriad orbital connective tissues as it harmoniously orchestrates binocular movements, ensuring synchronised and fluid visual tracking. Historically, the peripheral oculomotor apparatus was conceptualised as a rudimentary system predominantly driven by neural directives. While widely accepted, this perspective offered a limited view of the complexities inherent in ocular movement mechanics. The twentieth century heralded a paradigm shift in this understanding. With advances in anatomical research and imaging techniques, a much clearer picture of the gross anatomy of the EOMs emerged. This clarity challenged traditional viewpoints, suggesting that the inherent biomechanical properties of the EOMs, coupled with their associated tissue pulleys, play a pivotal role in dictating eye movement dynamics. Central to this revised understanding is the "arc of contact" paradigm. This concept delves deep into the mechanics of eye rotation, elucidating the significance of the point of contact between the EOMs and the eyeball. The arc of contact is not just a static anatomical feature; its length and orientation play a crucial role in determining the effective torque generated by a muscle, thereby influencing the amplitude and direction of eye rotation. The dynamic nature of this arc, influenced by the position and tension of the muscle pulleys, offers a more comprehensive model for understanding ocular kinematics. Previously overlooked in traditional models, muscle pulleys have now emerged as central players in the biomechanics of eye movement. These anatomical structures, formed by dense connective tissues, guide the paths of the EOMs, ensuring that their pulling angles remain optimal across a range of gaze directions. The non-linear paths resulting from these pulleys provide a more dynamic and intricate understanding of eye movement, challenging two-dimensional, linear models of orbital anatomy. The implications of these revelations extend beyond mere theoretical knowledge. The insights garnered from this research promise transformative potential in the realm of strabismus surgery. Recognising the pivotal role of muscle pulleys and the "arc of contact" paradigm allows for more precise surgical interventions, ensuring better post-operative outcomes and minimising the risk of complications. Surgical procedures that previously relied on basic mechanical principles now stand to benefit from a more nuanced understanding of the underlying anatomical and physiological dynamics. In conclusion, this manuscript serves as a testament to the ever-evolving nature of scientific knowledge. Challenging established norms and introducing fresh perspectives pave the way for more effective and informed clinical interventions in strabismus surgery.


Assuntos
Tecido Conjuntivo , Músculos Oculomotores , Órbita , Estrabismo , Humanos , Músculos Oculomotores/anatomia & histologia , Músculos Oculomotores/fisiologia , Estrabismo/cirurgia , Tecido Conjuntivo/anatomia & histologia , Tecido Conjuntivo/fisiologia , Órbita/anatomia & histologia , Movimentos Oculares/fisiologia , Fenômenos Biomecânicos/fisiologia
2.
Int Microbiol ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819732

RESUMO

The scarce antifungal arsenal, changes in the susceptibility profile of fungal agents, and lack of adherence to treatment have contributed to the increase of cases of dermatomycoses. In this context, new antimicrobial substances have gained importance. Chalcones are precursors of the flavonoid family that have multiple biological activities, have high tolerability by humans, and easy synthesis. In this study, we evaluated the in vitro antifungal activity, alone and in combination with conventional antifungal drugs, of the VS02-4'ethyl chalcone-derived compound against dermatophytes and Candida spp. Susceptibility testing was carried out by broth microdilution. Experiments for determination of the target of the compound on the fungal cell, time-kill kinetics, and toxicity tests in Galleria mellonella model were also performed. Combinatory effects were evaluated by the checkerboard method. Results showed high activity of the compound VS02-4'ethyl against dermatophytes (MIC of 7.81-31.25 µg/ml). The compound targeted the cell membrane, and the time-kill test showed the compound continues to exert gradual activity after 5 days on dermatophytes, but no significant activity on Candida. Low toxicity was observed at 250 mg/kg. Excellent results were observed in the combinatory test, where VS02-4'ethyl showed synergistic interactions with itraconazole, fluconazole, terbinafine, and griseofulvin, against all isolates tested. Although further investigation is needed, these results revealed the great potential of chalcone-derived compounds against fungal infections for which treatments are long and laborious.

3.
Cell Mol Life Sci ; 80(7): 185, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340282

RESUMO

DIS3L2 degrades different types of RNAs in an exosome-independent manner including mRNAs and several types of non-coding RNAs. DIS3L2-mediated degradation is preceded by the addition of nontemplated uridines at the 3'end of its targets by the terminal uridylyl transferases 4 and 7. Most of the literature that concerns DIS3L2 characterizes its involvement in several RNA degradation pathways, however, there is some evidence that its dysregulated activity may contribute to cancer development. In the present study, we characterize the role of DIS3L2 in human colorectal cancer (CRC). Using the public RNA datasets from The Cancer Genome Atlas (TCGA), we found higher DIS3L2 mRNA levels in CRC tissues versus normal colonic samples as well as worse prognosis in patients with high DIS3L2 expression. In addition, our RNA deep-sequencing data revealed that knockdown (KD) of DIS3L2 induces a strong transcriptomic disturbance in SW480 CRC cells. Moreover, gene ontology (GO) analysis of significant upregulated transcripts displays enrichment in mRNAs encoding proteins involved in cell cycle regulation and cancer-related pathways, which guided us to evaluate which specific hallmarks of cancer are differentially regulated by DIS3L2. To do so, we employed four CRC cell lines (HCT116, SW480, Caco-2 and HT-29) differing in their mutational background and oncogenicity. We demonstrate that depletion of DIS3L2 results in reduced cell viability of highly oncogenic SW480 and HCT116 CRC cells, but had little or no impact in the more differentiated Caco-2 and HT-29 cells. Remarkably, the mTOR signaling pathway, crucial for cell survival and growth, is downregulated after DIS3L2 KD, whereas AZGP1, an mTOR pathway inhibitor, is upregulated. Furthermore, our results indicate that depletion of DIS3L2 disturbs metastasis-associated properties, such as cell migration and invasion, only in highly oncogenic CRC cells. Our work reveals for the first time a role for DIS3L2 in sustaining CRC cell proliferation and provides evidence that this ribonuclease is required to support the viability and invasive behavior of dedifferentiated CRC cells.


Assuntos
Neoplasias Colorretais , Humanos , Células CACO-2 , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Células HCT116 , Proliferação de Células/genética , RNA Mensageiro , Movimento Celular/genética , Ribonucleases/genética , Regulação Neoplásica da Expressão Gênica , Exorribonucleases/genética , Exorribonucleases/metabolismo
4.
Acta Paediatr ; 113(2): 170-182, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37962097

RESUMO

AIM: This study is a systematic review and meta-analysis of randomised controlled trials that employed probiotics and symbiotics for treating infantile colic. METHODS: We performed electronic systematic literature searches in Embase, PubMed and Web of Science, to identify articles published between 1950 and April 2023. Only RCT involving infants with infantile colic under 3 months were included. The treatment plan comprised 15 probiotics, which included Lactobacillus reuteri DSM 17938 and Bifidobacterium animalis lactis BB-12. The probiotics were administered alone or in combination with a prebiotic, vs. no intervention or a placebo. RESULTS: Probiotics resulted in an average reduction of 51 min of crying per day (p = 0.001). Further analysis of subgroups showed that the reduction was -39.30 min for vaginal delivery (p = 0.003), -64.66 min for Lactobacillus reuteri DSM 17938 (p = 0.03), -40.45 min for other strains (p < 0.00001), -74.28 min for exclusively breastfed infants (p = 0.0003) and -48.04 min for mixed feeding (p < 0.00001). CONCLUSION: All probiotic strains seem effective in treating infantile colic. Exclusively breastfed infants have demonstrated more significant reduction in crying time. However, the available evidence on the effectiveness of probiotics in formula-fed and caesarean-born infants is limited.


Assuntos
Cólica , Limosilactobacillus reuteri , Probióticos , Lactente , Gravidez , Feminino , Humanos , Cólica/terapia , Aleitamento Materno , Probióticos/uso terapêutico , Emoções , Prebióticos
5.
Ann Surg ; 278(5): 823-831, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37555342

RESUMO

OBJECTIVE: To assess the rate of textbook outcome (TO) and textbook oncological outcome (TOO) in the European population based on the GASTRODATA registry. BACKGROUND: TO is a composite parameter assessing surgical quality and strongly correlates with improved overall survival. Following the standard of treatment for locally advanced gastric cancer, TOO was proposed as a quality and optimal multimodal treatment parameter. METHODS: TO was achieved when all the following criteria were met: no intraoperative complications, radical resection according to the surgeon, pR0 resection, retrieval of at least 15 lymph nodes, no severe postoperative complications, no reintervention, no admission to the intensive care unit, no prolonged length of stay, no postoperative mortality and no hospital readmission. TOO was defined as TO with the addition of perioperative chemotherapy compliance. RESULTS: Of the 2558 patients, 1700 were included in the analysis. TO was achieved in 1164 (68.5%) patients. The use of neoadjuvant chemotherapy [odds ratio (OR) = 1.33, 95% CI: 1.04-1.70] and D2 or D2+ lymphadenectomy (OR = 1.55, 95% CI: 1.15-2.10) had a positive impact on TO achievement. Older age (OR = 0.73, 95% CI: 0.54-0.94), pT3/4 (OR = 0.79, 95% CI: 0.63-0.99), ASA 3/4 (OR = 0.68, 95% CI: 0.54-0.86) and total gastrectomy (OR = 0.56, 95% CI: 0.45-0.70), had a negative impact on TO achievement. TOO was achieved in 388 (22.8%) patients. Older age (OR = 0.37, 95% CI: 0.27-0.53), pT3 or pT4 (OR = 0.52, 95% CI: 0.39-0.69), and ASA 3 or 4 (OR = 0.58, 95% CI: 0.43-0.79) had a negative impact on TOO achievement. CONCLUSIONS: Despite successively improved surgical outcomes, stage-appropriate chemotherapy in adherence to the current guidelines for multimodal treatment of gastric cancer remains poor. Further implementation of oncologic quality metrics should include greater emphasis on perioperative chemotherapy and adequate lymphadenectomy.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Excisão de Linfonodo/efeitos adversos , Linfonodos/patologia , Gastrectomia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Resultado do Tratamento
6.
Nitric Oxide ; 132: 15-26, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36736618

RESUMO

Spatial confinement and temporal regulation of signaling by nitric oxide (NO) and reactive oxygen species (ROS) occurs in cancer cells. Signaling mediated by NO and ROS was investigated in two sub clones of the murine melanoma B16F10-Nex2 cell line, Nex10C and Nex8H treated or not with bradykinin (BK). The sub clone Nex10C, similar to primary site cells, has a low capacity for colonizing the lungs, whereas the sub clone Nex8H, similar to metastatic cells, corresponds to a highly invasive melanoma. BK-treated Nex10C cells exhibited a transient increase in NO and an inhibition in basal O2- levels. Inhibition of endogenous NO production by l-NAME resulted in detectable levels of O2-. l-NAME promoted Rac1 activation and enhanced Rac1-PI3K association. l-NAME in the absence of BK resulted in Nex10C cell migration and invasion, suggesting that NO is a negative regulator of O2- mediated cell migration and cell invasion. BK-treated Nex8H cells sustained endogenous NO production through the activation of NOS3. NO activated Rac1 and promoted Rac1-PI3K association. NO stimulated cell migration and cell invasion through a signaling axis involving Ras, Rac1 and PI3K. In conclusion, a role for O2- and NO as positive regulators of Rac1-PI3K signaling associated with cell migration and cell invasion is proposed respectively for Nex10C and Nex8H murine melanoma cells.


Assuntos
Bradicinina , Melanoma , Camundongos , Animais , Bradicinina/farmacologia , Bradicinina/metabolismo , Superóxidos , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Movimento Celular
7.
BMC Ophthalmol ; 23(1): 512, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38102543

RESUMO

BACKGROUND: Overelevation in adduction is common in patients with primary esotropia. This study evaluates the variation in ocular motility pattern in patients with primary inferior oblique (IO) muscle overaction after esotropia surgery. METHODS: The medical records of consecutive patients who underwent surgery for infantile, partially accommodative, and basic esotropia over eleven years and had at least one year of follow-up were reviewed. Patients with primary inferior oblique muscle overaction (IOOA) presented at baseline or during follow-up were selected and divided according to the first surgery performed concurrently with horizontal rectus surgery: without IO recession (NO-recess), with unilateral IO recession (UNIL-recess), and with bilateral IO recession (BIL-recess). The success (version normalisation or at least 2 points upgrade in severity scale [0-4] in the operated eye), recurrence rates, and the evolution of the non-operated IO muscles were evaluated. RESULTS: One hundred and ten patients were included - 53 NO-recess, 26 UNIL-recess, and 31 BIL-recess. Medial rectus muscle posterior fixation sutures surgery (PFS) was performed in 88.2% of patients for esotropia. A recession with graded anterior transposition was the weakening IO procedure. In the NO-recess group, 28 (52.8%) patients normalised their mild IOOA after PFS surgery alone. In the UNI-recess group, the success rate was 88.5%, with 16 (61.5%) patients showing worsened IO muscle of the fellow eye, which prompted additional surgery in 10 patients. In the BIL-recess group, all 31 patients improved the adduction pattern of the operated eye for an 80.6% success rate (6 improved marginally). CONCLUSION: Graded anterior transposition of the inferior oblique muscle effectively normalises versions. However, it's frequent for a contralateral overaction to become manifest after unilateral IO surgery.


Assuntos
Esotropia , Doenças Musculares , Transtornos da Motilidade Ocular , Doenças Orbitárias , Estrabismo , Humanos , Esotropia/cirurgia , Resultado do Tratamento , Procedimentos Cirúrgicos Oftalmológicos/métodos , Estudos Retrospectivos , Músculos Oculomotores/cirurgia , Visão Binocular/fisiologia , Estrabismo/cirurgia
8.
Environ Microbiol ; 24(10): 4702-4713, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35726894

RESUMO

The expansion of mcr-carrying bacteria is a well-recognized public health problem. Measures to contain mcr spread have mainly been focused on the food-animal production sector. Nevertheless, the spread of MCR producers at the environmental interface particularly driven by the increasing population of gulls in coastal cities has been less explored. Occurrence of mcr-carrying Escherichia coli in gull's colonies faeces on a Portuguese beach was screened over 7 months. Cultural, molecular and genomic approaches were used to characterize their diversity, mcr plasmids and adaptive features. Multidrug-resistant mcr-1-carrying E. coli were detected for 3 consecutive months. Over time, multiple strains were recovered, including zoonotic-related pathogenic E. coli clones (e.g. B2-ST131-H22, A-ST10 and B1-ST162). Diverse mcr-1 genetic environments were mainly associated with ST2/ST4-HI2 (ST10, ST131, ST162, ST354 and ST4204) but also IncI2 (ST12990) plasmids or in the chromosome (ST656). Whole-genome sequencing revealed enrichment of these strains on antibiotic resistance, virulence and metal tolerance genes. Our results underscore gulls as important spreaders of high-priority bacteria and genes that may affect the environment, food-animals and/or humans, potentially undermining One-Health strategies to reduce colistin resistance.


Assuntos
Charadriiformes , Infecções por Escherichia coli , Proteínas de Escherichia coli , Animais , Antibacterianos/farmacologia , Células Clonais , Colistina , Farmacorresistência Bacteriana/genética , Escherichia coli , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Humanos , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Gado , Testes de Sensibilidade Microbiana , Plasmídeos/genética
9.
Crit Rev Food Sci Nutr ; : 1-22, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36269014

RESUMO

Hypertension is the leading risk factor for cardiovascular diseases and is associated with intestinal dysbiosis with a decrease in beneficial microbiota. Probiotics can positively modulate the impaired microbiota and impart benefits to the cardiovascular system. Among them, the emended Lactobacillus has stood out as a microorganism capable of reducing blood pressure, being the target of several studies focused on managing hypertension. This review aimed to present the potential of Lactobacillus as an antihypertensive non-pharmacological strategy. We will address preclinical and clinical studies that support this proposal and the mechanisms of action by which these microorganisms reduce blood pressure or prevent its elevation.

10.
Cell Biol Int ; 46(1): 158-169, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34719858

RESUMO

Low levels of nitric oxide (NO) produced by constitutively expressed inducible NO synthase (NOS2) in tumor cells may be an important factor in their development. NOS2 expression is associated with high mortality rates for various cancers. Alternative splicing of NOS2 down-regulates its enzymatic activity, resulting in decreased intracellular NO concentrations. Specific probes to detect alternative splicing of NOS2 were used in two isogenic human colon cancer cell lines derived either from the primary tumor (SW480) or from a lymph node metastasis (SW620). Splicing variant of NOS2 S3, lacking exons 9, 10, and 11, was overexpressed in SW480 cells. NOS2 S3 was silenced in SW480 cells. Flow-cytometry analysis was used to estimate the intracellular NO levels and to analyze the cell cycle of the studied cell lines. Western blot analysis and quantitative real-time polymerase chain reaction (qRT-PCR) were used to determine apoptosis and autophagy markers. SW480 and SW620 cells expressed NOS2 S3. Overexpression of the NOS2 S3 in SW480 cells downregulated intracellular NO levels. SW480 cells with knocked down NOS2 S3 (referred to as S3C9 cells) had higher intracellular levels of NO compared to the wild-type SW480 cells under serum restriction. Higher NO levels resulted in the loss of viability of S3C9 cells, which was associated with autophagy. Induction of autophagy by elevated intracellular NO levels in S3C9 cells under serum restriction, suggests that autophagy operates as a cytotoxic response to nitrosative stress. The expression of NOS2 S3 plays an important role in regulating intracellular NO production and maintaining viability in SW480 cells under serum restriction. These findings may prove significant in the design of NOS2/NO-based therapies for colon cancer.


Assuntos
Adenocarcinoma/enzimologia , Autofagia , Neoplasias do Colo/enzimologia , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Estresse Nitrosativo , Adenocarcinoma/genética , Adenocarcinoma/secundário , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Óxido Nítrico Sintase Tipo II/genética , Isoformas de Proteínas , Transdução de Sinais
11.
Bioorg Med Chem Lett ; 67: 128743, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35447343

RESUMO

Antimicrobial resistance arises due to several adaptation mechanisms, being the overexpression of efflux pumps (EPs) one of the most worrisome. In bacteria, EPs can also play important roles in virulence, quorum-sensing (QS) and biofilm formation. To identify new potential antimicrobial adjuvants, a library of diarylpentanoids and chalcones was synthesized and tested. These compounds presented encouraging results in potentiating the activity of antimicrobials, being diarylpentanoid 13 the most promising. Compounds 9, 13, 16, 19, 22, and 23 displayed EP inhibitory effect, mainly in Staphylococcus aureus 272123. Compounds 13, 19, 22, and 23 exhibited inhibitory effect on biofilm formation in S. aureus 272,123 while 13 and 22 inhibited QS in the pair Sphingomonas paucimobilis Ezf 10-17 and Chromobacterium violaceum CV026. The overall results, demonstrated that diarylpentanoid 13 and chalcone 22 were active against all the resistance mechanisms tested, suggesting their potential as antimicrobial adjuvants.


Assuntos
Chalcona , Chalconas , Antibacterianos/farmacologia , Biofilmes , Chalcona/farmacologia , Chalconas/farmacologia , Chromobacterium , Percepção de Quorum , Staphylococcus aureus
12.
Mar Drugs ; 20(5)2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35621966

RESUMO

The growing number of infectious diseases around the world threatens the effective response of antibiotics, contributing to the increase in antibiotic resistance seen as a global health problem. Currently, one of the main challenges in antimicrobial drug discovery is the search for new compounds that not only exhibit antimicrobial activity, but can also potentiate the antimicrobial activity and revert antibiotics' resistance, through the interference with several mechanisms, including the inhibition of efflux pumps (EPs) and biofilm formation. Inspired by macroalgae brominated bromophenol BDDE with antimicrobial activity, a series of 18 chalcone derivatives, including seven chalcones (9-15), six dihydrochalcones (16-18, and 22-24) and five diarylpropanes (19-21, and 25 and 26), was prepared and evaluated for its antimicrobial activity and potential to fight antibiotic resistance. Among them, chalcones 13 and 14 showed promising antifungal activity against the dermatophyte clinical strain of Trichophyton rubrum, and all compounds reversed the resistance to vancomycin in Enterococcus faecalis B3/101, with 9, 14, and 24 able to cause a four-fold decrease in the MIC of vancomycin against this strain. Compounds 17-24 displayed inhibition of EPs and the formation of biofilm by S. aureus 272123, suggesting that these compounds are inhibiting the EPs responsible for the extrusion of molecules involved in biofilm-related mechanisms. Interestingly, compounds 17-24 did not show cytotoxicity in mouse embryonic fibroblast cell lines (NIH/3T3). Overall, the results obtained suggest the potential of dihydrochalcones 16-18 and 22-24, and diarylpropanes 19-21, 25 and 26, as hits for bacterial EPs inhibition, as they are effective in the inhibition of EPs, but present other features that are important in this matter, such as the lack of antibacterial activity and cytotoxicity.


Assuntos
Anti-Infecciosos , Chalcona , Chalconas , Micoses , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Chalcona/farmacologia , Chalconas/farmacologia , Fibroblastos , Camundongos , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Relação Estrutura-Atividade , Vancomicina/farmacologia
13.
Int J Mol Sci ; 24(1)2022 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-36613773

RESUMO

Over recent decades, multidrug-resistant pathogens have become a global concern, with WHO even considering it one of the biggest threats to global health, food security, and development today, which led to the search for alternative antibacterial agents. A special class is formed by peptides composed by the diphenylalanine motif whose antibacterial properties result from their supramolecular arrangement into nanotubes. However, several other dipeptides that also form nanotubes have been largely overlooked. Here, we present the antibacterial activity of four dipeptide nanotubes. The results point to diverse mechanisms through which dipeptide nanotubes exert their effect against bacteria. Antibacterial activity was similar for dipeptide nanotubes sufficiently wide to allow water flux while dipeptides displaying smaller channels were inactive. This suggests that two of the tested dipeptides, L-Phe-L-Phe (FF, diphenylalanine) and L-Leu-L-Ser (LS), are pore forming structures able to induce membrane permeation and affect cellular hydration and integrity. Of these two dipeptides, only FF demonstrated potential to inhibit biofilm formation. The amyloid-like nature and hydrophobicity of diphenylalanine assemblies are probably responsible for their adhesion to cell surfaces preventing biofilm formation and bacteria attachment.


Assuntos
Dipeptídeos , Nanotubos , Dipeptídeos/farmacologia , Dipeptídeos/química , Nanotubos/química , Peptídeos/química , Antibacterianos/farmacologia , Fenilalanina/química , Biofilmes
14.
Int J Mol Sci ; 23(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36430768

RESUMO

Resistance to antibiotics is an emerging problem worldwide, which leads to an increase in morbidity and mortality rates. Several mechanisms are attributed to bacterial resistance, overexpression of efflux pumps being one of the most prominent. As an attempt to develop new effective antimicrobial drugs, which could be able to act against resistant bacterial strains and considering the antimicrobial potential of flavonoids and triazolyl flavonoid derivatives, in particular chalcones, a small library of chalcone derivatives was synthesized and evaluated for its potential to act as antimicrobials and/or adjuvants in combination with antibiotics towards resistant bacteria. Although only compound 7 was able to act as antibacterial, compounds 1, 2, 4, 5, 7, and 9 revealed to be able to potentiate the activity of antibiotics in resistant bacteria. Moreover, five compounds (3, 5-8) demonstrated to be effective inhibitors of efflux pumps in Salmonella enterica serovar Typhimurium SL1344, and four compounds (1, 3, 7, and 10) showed higher ability than reserpine to inhibit biofilm formation of resistant Staphylococcus aureus 272123. Together, our results showed the potential of these compounds regarding reversion of bacterial resistance.


Assuntos
Anti-Infecciosos , Chalcona , Chalconas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Chalcona/farmacologia , Chalconas/farmacologia , Triazóis/farmacologia , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Bactérias , Salmonella typhimurium , Resistência a Múltiplos Medicamentos
15.
Int J Mol Sci ; 23(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36430942

RESUMO

The overexpression of efflux pumps is one of the strategies used by bacteria to resist antibiotics and could be targeted to circumvent the antibiotic crisis. In this work, a series of trimethoxybenzoic acid derivatives previously described as antifouling compounds was explored for potential antimicrobial activity and efflux pump (EP) inhibition. First, docking studies on the acridine resistance proteins A and B coupled to the outer membrane channel TolC (AcrAB-TolC) efflux system and a homology model of the quinolone resistance protein NorA EP were performed on 11 potential bioactive trimethoxybenzoic acid and gallic acid derivatives. The synthesis of one new trimethoxybenzoic acid derivative (derivative 13) was accomplished. To investigate the potential of this series of 11 derivatives as antimicrobial agents, and in reverting drug resistance, the minimum inhibitory concentration was determined on several strains (bacteria and fungi), and synergy with antibiotics and EP inhibition were investigated. Derivative 10 showed antibacterial activity against the studied strains, derivatives 5 and 6 showed the ability to inhibit EPs in the acrA gene inactivated mutant Salmonella enterica serovar Typhimurium SL1344, and 6 also inhibited EPs in Staphylococcus aureus 272123. Structure-activity relationships highlighted trimethoxybenzoic acid as important for EP inhibitory activity. Although further studies are necessary, these results show the potential of simple trimethoxybenzoic acid derivatives as a source of feasible EP inhibitors.


Assuntos
Proteínas de Bactérias , Ácido Gálico , Ácido Gálico/farmacologia , Ácido Gálico/metabolismo , Proteínas de Bactérias/metabolismo , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Staphylococcus aureus/metabolismo
16.
BMC Ophthalmol ; 21(1): 119, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33673817

RESUMO

BACKGROUND: This paper fills a gap in the applied research field, for a local context, by addressing the topics of describing cataract surgery' clinical outcomes; quality of life (QoL); and costs of the patients treated after the implementation of the ICHOM standard set. METHODS: This is a retrospective observational study using real-world data (RWD). We included all patients subjected to cataract surgery at the Portuguese Institute of oncology - Porto (IPO-Porto), Portugal, after 3 months follow up period completed between 5th June 2017 and 21st May 2018. The following inclusion criteria: corrected visual acuity of ≤ 6/10 or other significant visual disturbance due to lens opacity or the existence of a large anisometropia. A circuit was implemented based on the ICHOM standard for cataract, to measure clinical variables (e.g. visual acuity) and QoL (CATQUEST-9SF) before and after surgery, and cost of treatment. The results were explored by means of a paired-sample t-test, considering normality assumptions. RESULTS: Data refers to 268 patients (73 P25-P75:32-95 years old), regarding 374 eyes. The cataract surgery had a positive effect on visual acuity (p < 0.001), refraction (right and left cylinder; p < 0.001) and all QoL dimensions. The vast majority of patients, around 98%, reported improvements in QoL. Based on IPO-Porto administrative records, the direct cost of treating cataracts (per eye) is of 500€, representing a total cost of 187,000€ for the number of patients operated herein. CONCLUSION: This study reports the successful implementation of the ICHOM standard set for cataracts in a Portuguese institution and confirms that cataract surgery provides a rapid visual recovery, with excellent visual outcomes and minimal complications in most patients, while also having a positive impact on patients' quality of life.


Assuntos
Extração de Catarata , Catarata , Adulto , Idoso , Idoso de 80 Anos ou mais , Catarata/complicações , Humanos , Pessoa de Meia-Idade , Portugal , Qualidade de Vida , Acuidade Visual
17.
J Fish Biol ; 98(2): 548-556, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33111352

RESUMO

Otolith shape analysis is a powerful method for fish stock identification. We compared the otolith shape of Pagrus pagrus (Linnaeus 1758) along with its distribution in four south-western Atlantic regions where it is commercially fished: Rio de Janeiro, Rio Grande do Sul in southern Brazil, the Argentine-Uruguayan Common Fishing Zone (UA) and the Argentinian Exclusive Fishing Zone (AR). Otolith shapes were compared by Elliptical Fourier and Wavelet coefficients among specimens in a size range with similar otoliths, morphometric parameters and ages. Four potential stocks were identified: one in the AR, a second along the UA which included specimens from southern Brazil with well-marked opaque bands in its otoliths (MRS), the third in southern Brazil with faint or absent opaque bands in its otoliths (FRS) and the fourth along Rio de Janeiro. The difference in the otolith shape among regions followed differences reported using other stock identification techniques. The similarity between otoliths from UA and MRS (ANOVA-like, P > 0.01) can be explained by seasonal short-range migrations. Otoliths shape differences between MRS and FRS (ANOVA-like, P < 0.01) suggest that P. pagrus does not form a homogeneous group in southern Brazil.


Assuntos
Membrana dos Otólitos/anatomia & histologia , Perciformes/anatomia & histologia , Perciformes/classificação , Animais , Oceano Atlântico , Brasil , Pesqueiros , Especificidade da Espécie
18.
Food Microbiol ; 89: 103415, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32138985

RESUMO

Hepatitis E virus (HEV) deriving from manure application runoffs and faecal waste spill over of swine and human origin bypass wastewater treatment plants and contaminate coastal waters. Shellfish bioaccumulate enteric viruses such as HEV from fecally contaminated coastal waters and under current European Regulations, shellfish sanitary status surveillance is mandatory but only by means of bacterial faecal indicators. The sea urchins are under the same regulations and their vulnerability to fecal contamination has been pointed out. Since they are consumed raw and with no steps to control/reduce hazards, sea urchin contamination with enteric viruses can represent a food safety risk. Hence, the aim of the present study was to screen sea urchin gonads destined for human consumption for the presence of HEV. HEV was detected and quantified in gonads of sea urchins collected in north Portugal by a reverse transcription-quantitative PCR (RT-qPCR) assay targeting the ORF3 region, followed by genotyping by a nested RT-PCR targeting the ORF2 region. Sequencing and phylogenetic analysis clustered the HEV sequence within genotype 3, subgenotype e. This the first study reporting HEV contamination of sea urchins. We hypothesize that like shellfish, sea urchins can also be a food vehicle for HEV transmission to humans.


Assuntos
Contaminação de Alimentos , Genótipo , Vírus da Hepatite E/genética , Paracentrotus/virologia , Frutos do Mar/virologia , Animais , Gônadas/virologia , Filogenia , Portugal , Reação em Cadeia da Polimerase em Tempo Real
19.
Eur Arch Otorhinolaryngol ; 277(6): 1815-1822, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32157434

RESUMO

INTRODUCTION: Post-tonsillectomy pain is mediated by nociceptive C-fibers located at peritonsillar space. Peritonsillar infiltration of medication could relieve post-operative pain blocking the afferent via. PURPOSE: To evaluate the effect of peritonsillar infiltration of tramadol, ketamine, and placebo on post-operative pain in cases of adenotonsillectomy. METHODS: This is a double-blind randomized placebo-controlled study. Children ASA I-II aged 3-13 years scheduled for adenotonsillectomy were included in the study. Patients were randomized to receive either 2 mg/kg of peritonsillar tramadol (Group T), 0.5 mg/kg of peritonsillar ketamine hydrochloride (Group K), and 3 mL of peritonsillar saline (Group P). Post-operative pain was recorded using the modified visual analogue scale at 2 h, 6 h, 12 h, and 24 h. Side effects, analgesia requirement, and first oral intake were also recorded. RESULTS: There were included 112 patients and five were excluded until final evaluation. We evaluated 36 children of Group T, 36 of Group K, and 35 of Group P. Groups were similar regarding to age, weight, height, gender, tonsil and adenoid size, hemodynamic parameters during the surgery, surgery, and anesthesia time. There were no differences between the groups in relation to pain scores, analgesia requirement, or first time of oral intake (p > 0.05). Group T presented a higher incidence of vomit between 2 and 6 h after surgery (p > 0.05). CONCLUSION: This study showed that peritonsillar infiltration of tramadol or ketamine were not superior to placebo in reducing post-operative pain in children undergone adenotonsillectomy. The use of tramadol increased the risk of nausea and vomit between 2 and 6 h after surgery.


Assuntos
Analgesia , Ketamina , Tonsilectomia , Tramadol , Adenoidectomia , Adolescente , Analgésicos Opioides , Criança , Pré-Escolar , Método Duplo-Cego , Humanos , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle
20.
Molecules ; 25(10)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32455828

RESUMO

A series of thirteen xanthones 3-15 was prepared based on substitutional (appendage) diversity reactions. The series was structurally characterized based on their spectral data and HRMS, and the structures of xanthone derivatives 1, 7, and 8 were determined by single-crystal X-ray diffraction. This series, along with an in-house series of aminated xanthones 16-33, was tested for in-vitro antimicrobial activity against seven bacterial (including two multidrug-resistant) strains and five fungal strains. 1-(Dibromomethyl)-3,4-dimethoxy-9H-xanthen-9-one (7) and 1-(dibromomethyl)-3,4,6-trimethoxy-9H-xanthen-9-one (8) exhibited antibacterial activity against all tested strains. In addition, 3,4-dihydroxy-1-methyl-9H-xanthen-9-one (3) revealed a potent inhibitory effect on the growth of dermatophyte clinical strains (T. rubrum FF5, M. canis FF1 and E. floccosum FF9), with a MIC of 16 µg/mL for all the tested strains. Compounds 3 and 26 showed a potent inhibitory effect on two C. albicans virulence factors: germ tube and biofilm formation.


Assuntos
Antibacterianos/química , Biofilmes/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Xantonas/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/patogenicidade , Biofilmes/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Cristalografia por Raios X , Humanos , Testes de Sensibilidade Microbiana , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/farmacologia , Difração de Raios X , Xantonas/síntese química , Xantonas/farmacologia
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