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1.
Curr Microbiol ; 80(1): 24, 2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36462098

RESUMO

Plectranthus amboinicus is widely recognized as a potential source of antimicrobial compounds due to the presence of bioactive components (essential oils) secreted by the glandular trichomes borne on the leaves. As such, an understanding of the effect of leaf development on the production of these essential oils (EOs) is of crucial importance to its medicinal applications. The current study represents the first comparative investigation of the effect of different stages of leaf development (lag, log, and stationary phase) upon the yield and bioactivity of phytochemicals produced. The effects of leaf extracts on the antimicrobial activity, cell surface hydrophobicity, biofilm formation, and motility of P. aeruginosa and Staphylococcus aureus were evaluated. Cryo-scanning electron microscopy was used to record the abundance and distribution of both glandular and non-glandular trichomes during leaf development. Gas chromatography-mass spectrometry analysis revealed that the potent phytochemical thymol is present primarily in log (30.28%) and stationary phase (20.89%) extracts. Log phase extracts showed the lowest minimum inhibitory concentration (25 mg/ml) when compared to other phases of development. Stationary phase extracts were shown to exhibit the highest biofilm dispersal activity against P. aeruginosa (80%), and log phase extracts against biofilms of S. aureus (59%). Log phase extracts showed the highest biofilm inhibitory activity against P. aeruginosa (66%) and S. aureus (63%). In conclusion, log phase leaf extracts of P. amboinicus exhibited a multimodal mechanism of action by displaying antimicrobial, antibiofilm activities and reducing the motility and hydrophobicity, which are important virulence factors in P. aeruginosa and S. aureus pathogenesis.


Assuntos
Óleos Voláteis , Plectranthus , Infecções Estafilocócicas , Staphylococcus aureus , Pseudomonas aeruginosa , Fatores de Virulência , Óleos Voláteis/farmacologia
2.
Pharm Dev Technol ; 26(1): 101-109, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33078682

RESUMO

There is a need to accelerate paediatric formulation evaluation and enhance quality of early stage data in drug development to alleviate the information pinch point present between formulation development and clinical evaluation. This present work reports application of DNA microarrays as a high throughput screening tool identifying markers for prediction of bioavailability and formulation driven physiological responses. With a focus on enhancing paediatric medicine provision, an oral liquid spironolactone suspension was formulated addressing a paediatric target product profile. Caco-2 cells cultured on transwell inserts were implemented in transport assays in vitro and DNA microarrays were used to examine gene expression modulation. Wistar rats were used to derive in vivo bioavailability data. In vitro, genomic, and in vivo data sets were concurrently evaluated linking drug transport and the genomic fingerprint generated by spironolactone formulation exposure. Significant changes in gene expression are reported as a result of formulation exposure. These include genes coding for ATP-binding cassette (ABC) transporters, solute carrier (SLC) transporters, cytochrome P450 (CYP) enzymes, and carboxylesterase enzymes. Genomic findings better inform pre-clinical understanding of pharmacokinetic and pharmacodynamic responses to spironolactone and its active metabolites than current in vitro drug transport assays alone.


Assuntos
Composição de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Perfilação da Expressão Gênica/métodos , Espironolactona/administração & dosagem , Espironolactona/farmacocinética , Fatores Etários , Animais , Células CACO-2 , Diuréticos/administração & dosagem , Diuréticos/química , Diuréticos/farmacocinética , Expressão Gênica , Humanos , Masculino , Ratos , Ratos Wistar , Espironolactona/química
3.
Acta Orthop Belg ; 87(2): 219-225, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34529373

RESUMO

Although distal radius fractures are quite common, bilateral distal radius fractures seldomly occur. Due to this, treatment is primarily based on surgeon experience with unilateral fractures, however bi- lateral fractures add a level of complexity : loss of functional independence. The purpose of this study was to examine a cohort of patients with bilateral distal radius fractures to identify differences in demographics, mechanism of injury, and outcomes to further our understanding of these rare injuries. 23 patients were identified retrospectively over a 5-year period that met inclusion criteria. The medical records were reviewed with multiple demographic and clinical parameters recorded and analyzed. Males were more likely to sustain high-energy mechanisms (80% vs. 53%). Patients <50 years old were more likely to sustain high-energy mechanisms (90% vs. 46%) and were more likely to be treated operatively (80% vs. 62%). The most commonly associated injury was a head injury (30%). All patients treated non-operatively reported minimal/no pain upon final follow-up where 57% of patients treated operatively noted regular pain. 75% of patients with medical comorbidities had minimal/no pain upon final follow- up. Conclusions : Patients with bilateral fractures were more likely to be younger males who suffered from higher energy mechanisms. Age was a critical factor in determining treatment strategy. Rates of associated head injuries were elevated, which is an important factor for the clinician to keep in mind when treating this population. As we further our understanding of this unique population, we can improve our treatment approaches and subsequently attain better outcomes.


Assuntos
Fraturas do Rádio , Estudos de Coortes , Demografia , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas do Rádio/epidemiologia , Fraturas do Rádio/cirurgia , Estudos Retrospectivos
6.
Medicina (Kaunas) ; 54(6)2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30513764

RESUMO

Background and objectives: The use of antibiotic prophylaxis in extraction and implant dentistry is still controversial, with varying opinions regarding their necessity. The overuse of antibiotics has led to widespread antimicrobial resistance and the emergence of multi drug resistant strains of bacteria. The main aim of this work was to determine whether there is a genuine need for antibiotic prophylaxis in two common dental procedures; dental implants and tooth extractions. Methods: Electronic searches were conducted across databases such as Cochrane Register of Controlled Trials, the UK National Health Service, Centre for reviews, Science Direct, PubMed and the British Dental Journal to identify clinical trials of either dental implants or tooth extractions, whereby the independent variable was systemic prophylactic antibiotics used as part of treatment in order to prevent postoperative complications such as implant failure or infection. Primary outcomes of interest were implant failure, and postoperative infections which include systemic bacteraemia and localised infections. The secondary outcome of interest was adverse events due to antibiotics. The Critical Appraisal Skills Programme tool was used to assess the risk of bias, extract outcomes of interest and to identify studies for inclusion in the meta-analysis. Results: Seven randomised clinical trials (RCTs) were included in the final review comprising n = 1368 patients requiring either tooth extraction(s) or dental implant(s). No statistically significant evidence was found to support the routine use of prophylactic antibiotics in reducing the risk of implant failure (p = 0.09, RR 0.43; 95% CI 0.16⁻1.14) or post-operative complications (p = 0.47, RR: 0.74; 95% CI 0.34⁻1.65) under normal conditions. Approximately 33 patients undergoing dental implant surgery need to receive antibiotics in order to prevent one implant failure from occurring. Conclusions: There is little conclusive evidence to suggest the routine use of antibiotic prophylaxis for third molar extractive surgery in healthy young adults. There was no statistical evidence for adverse events experienced for antibiotics vs. placebo. Based on our analysis, even if financially feasible, clinicians must carefully consider the appropriate use of antibiotics in dental implants and extraction procedures due to the risk of allergic reactions and the development of microbial drug resistance.


Assuntos
Antibacterianos/uso terapêutico , Antibioticoprofilaxia/métodos , Implantes Dentários , Extração Dentária , Adulto , Antibacterianos/efeitos adversos , Antibioticoprofilaxia/efeitos adversos , Bases de Dados Factuais , Farmacorresistência Bacteriana Múltipla , Endocardite/etiologia , Endocardite/mortalidade , Feminino , Humanos , Hipersensibilidade , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecção da Ferida Cirúrgica/tratamento farmacológico , Adulto Jovem
7.
PLoS Comput Biol ; 12(4): e1004884, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-27124473

RESUMO

The advent of functional genomics has enabled the genome-wide characterization of the molecular state of cells and tissues, virtually at every level of biological organization. The difficulty in organizing and mining this unprecedented amount of information has stimulated the development of computational methods designed to infer the underlying structure of regulatory networks from observational data. These important developments had a profound impact in biological sciences since they triggered the development of a novel data-driven investigative approach. In cancer research, this strategy has been particularly successful. It has contributed to the identification of novel biomarkers, to a better characterization of disease heterogeneity and to a more in depth understanding of cancer pathophysiology. However, so far these approaches have not explicitly addressed the challenge of identifying networks representing the interaction of different cell types in a complex tissue. Since these interactions represent an essential part of the biology of both diseased and healthy tissues, it is of paramount importance that this challenge is addressed. Here we report the definition of a network reverse engineering strategy designed to infer directional signals linking adjacent cell types within a complex tissue. The application of this inference strategy to prostate cancer genome-wide expression profiling data validated the approach and revealed that normal epithelial cells exert an anti-tumour activity on prostate carcinoma cells. Moreover, by using a Bayesian hierarchical model integrating genetics and gene expression data and combining this with survival analysis, we show that the expression of putative cell communication genes related to focal adhesion and secretion is affected by epistatic gene copy number variation and it is predictive of patient survival. Ultimately, this study represents a generalizable approach to the challenge of deciphering cell communication networks in a wide spectrum of biological systems.


Assuntos
Redes Reguladoras de Genes , Próstata/citologia , Próstata/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Teorema de Bayes , Comunicação Celular , Linhagem Celular , Linhagem Celular Tumoral , Técnicas de Cocultura , Biologia Computacional , Células Epiteliais/metabolismo , Perfilação da Expressão Gênica , Humanos , Masculino , Modelos Biológicos , Neoplasias da Próstata/metabolismo , Transdução de Sinais/genética
8.
Ultraschall Med ; 38(4): 420-426, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26529355

RESUMO

Purpose To report the feasibility, accuracy and initial clinical experience of the use of real-time magnetic resonance navigated ultrasound (rtMRnUS) in the surgical planning of breast-conserving surgery (BCS) via guide wire insertion. Materials and Methods 29 participants were recruited into this prospective ethics committee approved study. The first 4 cases were utilized as a training set. Participants underwent a supine contrast-enhanced breast MR examination with external fiducials and corresponding ink marks placed on the skin of the affected breast to act as co-registration pairs. MR examinations included both functional and morphological images. A LOGIQ E9 ultrasound system (GE Healthcare, Milwaukee, WI, USA) equipped with a 6 - 15 MHz transducer was utilized for rtMRnUS. To facilitate point co-registration of the previously acquired MR dataset with the real-time ultrasound, co-registration pairs were identified on both imaging modalities. The following co-registration quality metrics were recorded: root mean square deviation (RMSD), lesion and global accuracies. Post co-registration guide wire insertion was performed. Results Co-registration was successfully undertaken in all participants. Results from 25 participants are presented. The median (min, max) RMSD was 3.3 mm (0.6 mm, 8.8 mm). The global accuracy was assessed as very good (8), good (12), moderate (3) and poor (2) while the median (min, max) lesion accuracy was recorded at 8.9 mm (2.1 mm, 33.2 mm). Conclusion The use of rtMRnUS to facilitate guide wire insertion is a feasible technique. Generally, very good or good global registration can be expected. Lesion accuracy results indicate that a median difference, in 3 D space, of 9 mm can be expected between imaging modalities.


Assuntos
Neoplasias da Mama , Imageamento por Ressonância Magnética , Mamografia , Mastectomia Segmentar , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Estudos Prospectivos
9.
Eur J Immunol ; 45(11): 3045-51, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26300525

RESUMO

Invariant natural killer T (iNKT) cells recognize glycolipids as antigens and diversify into NKT1 (IFN-γ), NKT2 (IL-4), and NKT17 (IL-17) functional subsets while developing in the thymus. Mechanisms that govern the balance between these functional subsets are poorly understood due, partly, to the lack of distinguishing surface markers. Here we identify the heparan sulfate proteoglycan syndecan-1 (sdc1) as a specific marker of naïve thymic NKT17 cells in mice and show that sdc1 deficiency significantly increases thymic NKT17 cells at the expense of NKT1 cells, leading to impaired iNKT cell-derived IFN-γ, both in vitro and in vivo. Using surface expression of sdc1 to identify NKT17 cells, we confirm differential tissue localization and interstrain variability of NKT17 cells, and reveal that NKT17 cells express high levels of TCR-ß, preferentially use Vß8, and are more highly sensitive to ɑ-GalCer than to CD3/CD28 stimulation. These findings provide a novel, noninvasive, simple method for identification, and viable sorting of naïve NKT17 cells from unmanipulated mice, and suggest that sdc1 expression negatively regulates homeostasis in iNKT cells. In addition, these findings lay the groundwork for investigating the mechanisms by which sdc1 regulates NKT17 cells.


Assuntos
Células T Matadoras Naturais/imunologia , Sindecana-1/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Separação Celular/métodos , Perfilação da Expressão Gênica , Interleucina-17/biossíntese , Interleucina-17/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Células T Matadoras Naturais/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Subpopulações de Linfócitos T/metabolismo
10.
Arthritis Rheum ; 65(11): 2814-25, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23897050

RESUMO

OBJECTIVE: To evaluate the mechanism of fractalkine (FKN)/CX3 CL1 synthesis and shedding in rheumatoid arthritis synovial fibroblasts (RASFs) and in rat adjuvant-induced arthritis (AIA). METHODS: The effect of tumor necrosis factor α (TNFα) and/or interferon-γ (IFNγ) on FKN synthesis and shedding in human RASFs was determined over time by immunostaining, quantitative reverse transcription-polymerase chain reaction, and Western blotting. The role of protease enzymes and signaling pathways was evaluated using chemical inhibitors and small interfering RNA (siRNA). The activity of 20S proteasome in the lysates and the DNA binding of NF-κB/p65 in the nuclear fractions were evaluated. The in vivo relevance of these findings was examined in rat AIA. RESULTS: In RASFs, stimulation with the combination of TNFα and IFNγ induced cellular expression of FKN within 24 hours. Activation of ADAM-17, but not ADAM-10, partly mediated the proteolytic shedding and release of soluble FKN (sFKN) following TNFα/IFNγ stimulation for 24-72 hours. Compared with control siRNA, ADAM-17 siRNA markedly inhibited TNFα/IFNγ-induced sFKN production (by ∼33%). TNFα/IFNγ-induced sFKN release was markedly suppressed by inhibitors of ADAM-17, p38 MAPK, proteasome, or cathepsin inhibitor but not by inhibitors of caspase 3 or calpain. TNFα/IFNγ-induced proteasome activity also correlated with rapid degradation of IκBα and p38 MAPK phosphorylation. In vivo findings showed increased FKN expression in the joints of rats with AIA, which correlated with increased expression of ADAM-17 and phospho-p38 MAPK. CONCLUSION: Our results provide new understanding of the role of ADAM-17, p38 MAPK, cathepsins, and the proteasome pathway in FKN expression and shedding. Regulating these pathways may suppress FKN-mediated inflammation and tissue destruction.


Assuntos
Proteínas ADAM/metabolismo , Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Quimiocina CX3CL1/metabolismo , Proteínas ADAM/genética , Proteína ADAM10 , Proteína ADAM17 , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Artrite Experimental/patologia , Artrite Reumatoide/patologia , Catepsinas/metabolismo , Células Cultivadas , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , RNA Interferente Pequeno/genética , Ratos , Ratos Endogâmicos Lew , Membrana Sinovial/citologia , Membrana Sinovial/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Sci Rep ; 14(1): 19678, 2024 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-39181891

RESUMO

The formulation and delivery of macromolecules through the oral route pose considerable challenges due to factors such as large molecular weight, pH sensitivity, and limited formulation approaches. This challenge is compounded if the drug is poorly permeable, necessitating innovative drug delivery strategies. Vancomycin, a widely prescribed glycopeptide antibiotic, has an oral bioavailability of less than 10%, leading to predominantly intravenous administration and potential patient discomfort. This study explores the potential of the buccal route as a non-invasive, highly vascularised alternative route of administration, offering a rapid onset of action while bypassing the first-pass metabolism. In this study, vancomycin was coated with L-glutamic acid using an isothermal dry particle coater to modulate permeation through the buccal cell line, TR146. Results confirm significant impact of both amino acid concentration and dry particle coating on the rate and extent of drug permeability. With the introduction of L-glutamic acid and utilisation of the isothermal dry particle coater, vancomycin's permeation profile increased six-fold compared to the control due to the formation of drug ion-pair complex. Imaging studies showed the presence of layered micronized glutamic acid particles on the surface of dry coated vancomycin particles which confirms the role of dry coating and amino acid concentration in modulating drug permeation. Microbiology experiments in Staphylococcus aureus, minimum inhibitory concentration and biofilm disruption studies, provided confirmatory evidence of antimicrobial activity of dry coated glutamic acid-vancomycin ion pair particulate structure. This study demonstrates, for the first-time, buccal delivery of dry coated large molecule drug, vancomycin, through controlled deposition of amino acid using innovative particle coating strategy.


Assuntos
Antibacterianos , Vancomicina , Vancomicina/administração & dosagem , Vancomicina/farmacocinética , Humanos , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Antibacterianos/farmacocinética , Aminoácidos/química , Aminoácidos/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Mucosa Bucal/metabolismo , Permeabilidade/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Linhagem Celular , Ácido Glutâmico/metabolismo
12.
Front Physiol ; 15: 1393221, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39345785

RESUMO

Introduction: Frailty often manifests as an increased vulnerability to adverse outcomes, and detecting frailty is useful for informed healthcare decisions. Veterans are at higher risk for developing frailty and at younger ages. The goal of this study was to investigate approaches in Veterans that can better inform the physiologic underpinnings of frailty, including maximal oxygen uptake (VO2max), 6-min walk, muscle strength, and inflammatory biomarkers. Methods: Participants (N = 42) were recruited from the Buffalo VA Medical Center. Inclusion criteria: ages 60-85, male or female, any race, and not having significant comorbidities or cognitive impairment. Outcome measures included: the Fried frailty phenotype, the short physical performance battery (SPPB), quality of life (QOL) using the Q-LES-Q-SF, and the following physiologic assessments: VO2max assessment on an upright stationary bicycle, 6-min walk, and arm and leg strength. Additionally, inflammatory biomarkers (C-reactive protein, IL-6, IL-10, interferon-γ, and TNF-α) were measured using ELLA single and multiplex ELISA. Results: Participants: 70.3 ± 7.4 years of age: 34 males and 8 females, BMI = 30.7 ± 5.4 kg/m2, 26 white and 16 African American. A total of 18 (42.8%) were non-frail, 20 (47.6%) were pre-frail, and 4 (9.5%) were frail. VO2max negatively correlated with Fried frailty scores (r = -0.40, p = 0.03, N = 30), and positively correlated with SPPB scores (r = 0.50, p = 0.005), and QOL (r = 0.40, p = 0.03). The 6-min walk test also significantly correlated with VO2max (r = 0.57, p = 0.001, N = 42) and SPPB (r = 0.55, p = 0.0006), but did not quite reach a significant association with frailty (r = -0.28, p = 0.07). Arm strength negatively correlated with frailty (r = -0.47, p = 0.02, N = 26), but not other parameters. Inflammatory profiles did not differ between non-frail and pre-frail/frail participants. Conclusion: Objectively measured cardiorespiratory fitness was associated with important functional outcomes including physical performance, QOL, and frailty in this group of older Veterans. Furthermore, the 6-min walk test correlated with VO2max and SPPB, but more validation is necessary to confirm sensitivity for frailty. Arm strength may also be an important indicator of frailty, however the relationship to other indicators of physical performance is unclear.

13.
Toxicol Appl Pharmacol ; 270(2): 87-96, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23632129

RESUMO

In the present study, we evaluated the effect of largazole (LAR), a marine-derived class I HDAC inhibitor, on tumor necrosis factor-α (TNF-α)-induced expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), and matrix metalloproteinase-2 (MMP-2) activity. LAR (1-5 µM) had no adverse effect on the viability of RA synovial fibroblasts. Among the different class I HDACs screened, LAR (0.5-5 µM) inhibited the constitutive expression of HDAC1 (0-30%). Surprisingly, LAR increased class II HDAC [HDAC6] by ~220% with a concomitant decrease in HDAC5 [30-58%] expression in RA synovial fibroblasts. SAHA (5 µM), a pan-HDAC inhibitor, also induced HDAC6 expression in RA synovial fibroblasts. Pretreatment of RA synovial fibroblasts with LAR further enhanced TNF-α-induced ICAM-1 and VCAM-1 expression. However, LAR inhibited TNF-α-induced MMP-2 activity in RA synovial fibroblasts by 35% when compared to the TNF-α-treated group. Further, the addition of HDAC6 specific inhibitor Tubastatin A with LAR suppressed TNF-α+LAR-induced ICAM-1 and VCAM-1 expression and completely blocked MMP-2 activity, suggesting a role of HDAC6 in LAR-induced ICAM-1 and VCAM-1 expression. LAR also enhanced TNF-α-induced phospho-p38 and phospho-AKT expression, but inhibited the expression of phospho-JNK and nuclear translocation of NF-κBp65 in RA synovial fibroblasts. These results suggest that LAR activates p38 and Akt pathways and influences class II HDACs, in particular HDAC6, to enhance some of the detrimental effects of TNF-α in RA synovial fibroblasts. Understanding the exact role of different HDAC isoenzymes in RA pathogenesis is extremely important in order to develop highly effective HDAC inhibitors for the treatment of RA.


Assuntos
Artrite Reumatoide/metabolismo , Depsipeptídeos/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Molécula 1 de Adesão Intercelular/biossíntese , Membrana Sinovial/metabolismo , Tiazóis/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Molécula 1 de Adesão de Célula Vascular/biossíntese , Artrite Reumatoide/genética , Western Blotting , Sinergismo Farmacológico , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Molécula 1 de Adesão Intercelular/genética , Metaloproteinase 2 da Matriz/metabolismo , Proteína Oncogênica v-akt/metabolismo , RNA/química , RNA/genética , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/patologia , Molécula 1 de Adesão de Célula Vascular/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
14.
Nucleic Acids Res ; 39(17): 7512-28, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21690099

RESUMO

In order to develop an infection, diarrhogenic Escherichia coli has to pass through the stomach, where the pH can be as low as 1. Mechanisms that enable E. coli to survive in low pH are thus potentially relevant for pathogenicity. Four acid response systems involved in reducing the concentration of intracellular protons have been identified so far. However, it is still unclear to what extent the regulation of other important cellular functions may be required for survival in acid conditions. Here, we have combined molecular and phenotypic analysis of wild-type and mutant strains with computational network inference to identify molecular pathways underlying E. coli response to mild and strong acid conditions. The interpretative model we have developed led to the hypothesis that a complex transcriptional programme, dependent on the two-component system regulator OmpR and involving a switch between aerobic and anaerobic metabolism, may be key for survival. Experimental validation has shown that the OmpR is responsible for controlling a sizeable component of the transcriptional programme to acid exposure. Moreover, we found that a ΔompR strain was unable to mount any transcriptional response to acid exposure and had one of the strongest acid sensitive phenotype observed.


Assuntos
Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Redes Reguladoras de Genes , Adaptação Fisiológica/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Parede Celular/metabolismo , Metabolismo Energético , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Mutação , Fenótipo , Biologia de Sistemas , Transativadores/genética , Transativadores/fisiologia , Transcrição Gênica
15.
Pathogens ; 12(6)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37375543

RESUMO

Plectranthus amboinicus (Indian borage) has been extensively studied for its medicinal properties, which can be exploited to develop new antimicrobial therapeutics. The current study investigated the effect of Plectranthus amboinicus leaf extracts on the catalase activity, reactive oxygen species, lipid peroxidation, cytoplasmic membrane permeability, and efflux pump activity in S. aureus NCTC8325 and P. aeruginosa PA01. As the enzyme catalase protects bacteria against oxidative stress, disruption of its activity creates an imbalance in reactive oxygen species (ROS) levels, which subsequently oxidizes lipid chains, leading to lipid peroxidation. In addition, bacterial cell membranes are a potential target for new antibacterial agents, as efflux pump systems play a crucial role in antimicrobial resistance. Upon exposure of the microorganisms to Indian borage leaf extracts, the observed catalase activity decreased by 60% and 20% in P. aeruginosa and S. aureus, respectively. The generation of ROS can cause oxidation reactions to occur within the polyunsaturated fatty acids of the lipid membranes and induce lipid peroxidation. To investigate these phenomena, the increase in ROS activity in P. aeruginosa and S. aureus was studied using H2DCFDA, which is oxidized to 2',7'-dichlorofluorescein (DCF) by ROS. Furthermore, the concentration of lipid peroxidation product (malondialdehyde) was assessed using the Thiobarbituric acid assay and was shown to increase by 42.4% and 42.5% in P. aeruginosa and S. aureus, respectively. The effect of the extracts on the cell membrane permeability was monitored using diSC3-5 dye and it was observed that the cell membrane permeability of P. aeruginosa increased by 58% and of S. aureus by 83%. The effect on efflux pump activity was investigated using Rhodamine-6-uptake assay, which displayed a decrease in efflux activity of 25.5% in P. aeruginosa and 24.2% in S. aureus after treatment with the extracts. This combination of different methods to study various bacterial virulence factors provides a more robust, mechanistic understanding of the effect of P. amboinicus extracts on P. aeruginosa and S. aureus. This study thus represents the first report of the assessment of the effect of Indian borage leaf extracts on bacterial antioxidant systems and bacterial cell membranes, and can facilitate the future development of bacterial resistance modifying agents derived from P. amboinicus.

16.
SAGE Open Med ; 11: 20503121231208604, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-39139578

RESUMO

Objective: In Bangladesh, the factors that contribute to the reduced quality of life were not systematically investigated in long-term stroke survivors, and only a few studies have used preference-based measures to assess the quality of life. We sought to assess the quality of life in stroke survivors who comprise physical health status, psychological state, social relationship, and surrounding environment of the stroke patients. Methods: The quality of life among stroke patients was assessed with a semi-structured questionnaire using the validated Bangla Version of the World Health Organization, Quality-of-Life scale among the patients who survived beyond 28 days of first-ever stroke occurrence presenting in the Department of Physical Medicine and Rehabilitation, Bangabandhu Sheikh Mujib Medical University in the period between November 2020 and October 2021. Results: Of the 77 patients who were identified as post-stroke patients, the mean score of overall quality of life (as assessed by Q1 and scored in a range of 1-5) was 3.14 ± 1.08. The mean scores of quality of life were highest for the psychological domain (51.18 ± 19.73) followed by environmental (52.08 ± 13.13), social (45.62 ± 22.73), and physical domains (37.18 ± 18.56). According to the classification of the Bangla Version of the World Health Organization, Quality-of-Life, 75.3% had a low physical quality of life, 37.7% had a low psychological quality of life, 53.2% had a low social quality of life, and 53.2% had a moderate environmental quality of life. The average scores for the physical, psychological, social, and environmental domains were notably lower in stroke survivors with comorbid chronic conditions such as hypertension, diabetes, heart disease, asthma or chronic obstructive pulmonary disease, obesity, and ischemic heart disease in comparison to those without such conditions. Conclusion: In our study, post-stroke patients with lower quality of life were associated with factors such as female gender, lower level of education, urban dwellers, and chronic diseases.

17.
Cancer Rep (Hoboken) ; 5(3): e1484, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34196131

RESUMO

BACKGROUND: Yes-associated protein 1 (YAP1) is responsible for tumor growth, progression and metastasis. The mechanisms controlling the generation and relative ratio of the functional YAP1 and other co-factors are not well-understood. Various literature reported that co-factors like cytokines significantly influence signaling pathways to introduce epithelial immunity and regeneration, which later helps increase cancer-related phenotypes. Among various cytokines, IL-18 has emerged as a major player in inflammation and progression of different types of cancers. Till now, much information has not been known about the role of YAP1 in tumor aggressiveness and immune evasion in breast cancer with respect to IL-18. AIM: We aimed to explore the effect of YAP1 in tumor aggressiveness and immune evasion in breast invasive carcinoma and metastatic breast cancer in the context of Interleukin-18 (IL-18) in silico. METHODS AND RESULTS: We used publicly available data generated by The Cancer Genome Atlas (TCGA) Research Network through cBioportal web platform. Kaplan-Meier method was used to determine the overall survival and comparison between curves were made using Log-Rank test. The p values were determined by Fisher's exact test with the null hypothesis. Correlation plots were analyzed by comparison with gene copy numbers from the GISTIC2.0, available through cBioportal. Our analyses suggest that IL-18 influences YAP1 expression in breast oncogenesis via Interferon-gamma (IFN-γ) production. Patients having a higher expression of IL-18 possess a better prognosis and higher YAP1 expression with lower IL18 drives to poor clinical results in breast cancer. CONCLUSION: This can provide new approaches to better understand the relation between YAP1 and IL-18 in breast cancer progression by performing in vitro and in vivo studies. Also, IL-18 can be considered as a potential target for tumor treatment in YAP1 overexpressed breast carcinoma.


Assuntos
Neoplasias da Mama , Interleucina-18 , Proteínas de Sinalização YAP , Mama/patologia , Neoplasias da Mama/patologia , Carcinogênese/genética , Transformação Celular Neoplásica/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Interleucina-18/genética , Interleucina-18/metabolismo , Proteínas de Sinalização YAP/genética
18.
PLOS Glob Public Health ; 2(9): e0000930, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36962636

RESUMO

Rohingya refugees of Ukhiya, Cox's bazar are an unaccounted group of people who form the largest cluster of refugees worldwide. Non-communicable disease (NCD) alone causes 70% of worldwide deaths every year therefore, the trend of NCD among Rohingya refugees demands proper evaluation and attention. The objective of this study was to measure the NCD risk factors among a convenient sample of Rohingya refugees. This cross-sectional study was conducted among 249 Rohingya refugees living in Balukhali and Kutupalang Rohinga Camps at Ukhiya, Cox's bazaar using a survey dataset adapted from the WHO Stepwise approach to NCD Risk Factor Surveillance (STEPS). Data was collected through face-to-face interviews with a structured questionnaire. Anthropometric and biochemical measurements were done by trained medical assistants. Descriptive analysis was applied as appropriate for categorical variables. A Chi-square test and a student t test were performed to compare the categories. In general, the findings of NCD risk factors as per STEPS survey was 53.4% for tobacco use including smokeless tobacco, 2.8% for alcohol consumption, 23.7% for inadequate vegetable and fruit intake, 34.5% for taking extra salt, 89.6% for insufficient physical activity, 44.5%for confirmed hypertension, 16.9% for overweight, 1.2% for obesity and 0.8% for high blood sugar. Some modifiable non-communicable disease risk factors such as physical inactivity, tobacco smoking, extra salt with food, and hypertension are present among the Rohinga refugees in Bangladesh. These findings were timely and essential to support the formulation and implementation of NCD-related policies among the Rohingya refugees as a priority sub-population.

19.
Life (Basel) ; 12(8)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-36013325

RESUMO

Diabetes Mellitus (DM) is a metabolic disorder that is spreading alarmingly around the globe. Type-2 DM (T2DM) is characterized by low-grade inflammation and insulin resistance and is closely linked to obesity. T2DM is mainly controlled by lifestyle/dietary changes and oral antidiabetic drugs but requires insulin in severe cases. Many of the drugs that are currently used to treat DM are costly and present adverse side effects. Several cellular, animal, and clinical studies have provided compelling evidence that flavonoids have therapeutic potential in the management of diabetes and its complications. Quercetin is a flavonoid, present in various natural sources, which has demonstrated in vitro and in vivo antidiabetic properties. It improves oral glucose tolerance, as well as pancreatic ß-cell function to secrete insulin. It inhibits the α-glucosidase and DPP-IV enzymes, which prolong the half-life of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Quercetin also suppresses the release of pro-inflammatory markers such as IL-1ß, IL-4, IL-6, and TNF-α. Further studies are warranted to elucidate the mode(s) of action of quercetin at the molecular level. This review demonstrates the therapeutic potential of quercetin in the management of T2DM.

20.
Artigo em Inglês | MEDLINE | ID: mdl-34300053

RESUMO

Staphylococcus aureus is a nosocomial bacterium causing different infectious diseases, ranging from skin and soft tissue infections to more serious and life-threatening infections such as septicaemia. S. aureus forms a complex structure of extracellular polymeric biofilm that provides a fully secured and functional environment for the formation of microcolonies, their sustenance and recolonization of sessile cells after its dispersal. Staphylococcus aureus biofilm protects the cells against hostile conditions, i.e., changes in temperature, limitations or deprivation of nutrients and dehydration, and, more importantly, protects the cells against antibacterial drugs. Drugs are increasingly becoming partially or fully inactive against S. aureus as they are either less penetrable or totally impenetrable due to the presence of biofilms surrounding the bacterial cells. Other factors, such as evasion of innate host immune system, genome plasticity and adaptability through gene evolution and exchange of genetic material, also contribute to the ineffectiveness of antibacterial drugs. This increasing tolerance to antibiotics has contributed to the emergence and rise of antimicrobial resistance (AMR), a serious problem that has resulted in increased morbidity and mortality of human and animal populations globally, in addition to causing huge financial losses to the global economy. The purpose of this review is to highlight different aspects of S. aureus biofilm formation and its overall architecture, individual biofilm constituents, clinical implications and role in pathogenesis and drug resistance. The review also discusses different techniques used in the qualitative and quantitative investigation of S. aureus biofilm and various strategies that can be employed to inhibit and eradicate S. aureus biofilm.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Animais , Antibacterianos/farmacologia , Biofilmes , Humanos , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/genética
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