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1.
Mol Biol Rep ; 47(10): 7575-7582, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32930934

RESUMO

Thrombomodulin (THBD) is an endothelial surface glycoprotein receptor, having a pivotal role in maintaining laminar blood flow. It functions to protect endothelial integrity by exhibiting anti-coagulation and anti-inflammatory properties thereby playing a key role in cardiovascular disease (CVD) pathology. Cholesterol lowering drugs have shown to alter the anti-inflammatory effects of cytokines. Understanding the molecular aspects of THBD gene and its relation to inflammatory cytokines is important to identify new prognostic and therapeutic targets for the CVD treatments. The present study was conducted to measure the expression of THBD, TNF-α and NF-kB genes in coronary artery disease patients (CAD) in Pakistani population. Lipid profile and BMI was compared both on fifty CAD patients and fifty healthy individuals. Expression analysis for THBD, TNF-α and NF-kB was carried out using real time PCR. The effect of lipid lowering drugs on cardiometabolic risk variables especially gene expression was analyzed. Our results indicated that the difference in BMI was marginal; however LDL-cholesterol and triglycerides levels in CAD patients were significantly higher than healthy individuals. THBD gene was significantly up-regulated whereas TNF-α and NF-kB were significantly down regulated in CAD individuals. Further exploration revealed that these variations were accounted to the use of statins by the patients. The use of statins by CAD patients up-regulated the mRNA expression of THBD by down-regulation of inflammatory mediators. The enhanced expression of endothelial THBD in response to cholesterol lowering drugs establishes a novel pleiotropic target that can be of clinical significance in thromboembolic and inflammatory disorders.


Assuntos
Doença da Artéria Coronariana/metabolismo , Regulação da Expressão Gênica , NF-kappa B/biossíntese , Trombomodulina/biossíntese , Fator de Necrose Tumoral alfa/biossíntese , Adulto , Idoso , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão
2.
Psychol Rep ; : 332941241269449, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080923

RESUMO

Utilizing the social identity theory, this conceptual article has proposed how digitally mediated communication between expatriates and host country nationals (HCNs) in a remote work arrangement is linked with individualized change experiences of virtual expatriates. The conceptualized model proposes that the lack of in-depth conversations via virtual communication platforms leads to the development of weak emotional interactions between virtual expatriates and HCNs. However, weakened emotional interactions might result in positive or negative impact on expatriates' identity based on personality-based differences. In this regard, expatriates with collective self-esteem are likely to experience social identity threats because of weakened social ties with HCNs. Contrary to the above group, expatriates having personal self-esteem would view weak socialization as an opportunity and experience an improvement in their leader identity, thus experience a positive social identity change over time. This research has conceptually explored outcomes of digitally mediated communication between expatriates and HCNs on the identity change experiences of expatriates, and holistically covers the role of positive as well as negative change experiences. Unlike the focus of the majority of literature on traditional expatriation, the proposed model has focused on experiences of virtual expatriates, and how working in remote work settings lead to long-term socio-psychological changes in these individuals.

3.
Psychol Rep ; : 332941231207956, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37876183

RESUMO

The Covid outbreak and the resulting work processes have led to excessive work pressure requirements for a large majority of the employees due to continuous requirements for adaptation to changing work processes. However, outcomes of new work dynamics on employees' behavioral and attitudinal changes have been insufficiently examined during and after the Covid period. Hence, this empirical research has used the social identity theory to conceptualize and test the relationship between excessive work time and the entrepreneurial behavior of employees. Moreover, the mediating role of socialization tactics and creative self-efficacy, as well as the moderating role of resilience are also examined in the above relationship for unveiling the role of crucial intervening and conditional factors in individualized change experiences. Based on the analysis of data collected from managerial-level employees through the use of structural equation modeling, the empirical results have suggested a negative impact of excessive work time on the entrepreneurial behavior of employees. Also, the intervening role of formal socialization and creative self-efficacy were found to be significant in this relationship, thus suggesting the crucial direct as well as indirect relationships. Using the findings, implications as well as future research directions are discussed towards the end of the article.

4.
ACS Infect Dis ; 9(12): 2436-2447, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38009640

RESUMO

The repotentiation of the existing antibiotics by exploiting the combinatorial potential of antimicrobial peptides (AMPs) with them is a promising approach to address the challenges of slow antibiotic development and rising antimicrobial resistance. In the current study, we explored the ability of lead second generation Ana-peptides viz. Ana-9 and Ana-10, derived from Alpha-Melanocyte Stimulating Hormone (α-MSH), to act synergistically with different classes of conventional antibiotics against methicillin-resistant Staphylococcus aureus (MRSA). The peptides exhibited prominent synergy with ß-lactam antibiotics, namely, oxacillin, ampicillin, and cephalothin, against planktonic MRSA. Furthermore, the lead combination of Ana-9/Ana-10 with oxacillin provided synergistic activity against clinical MRSA isolates. Though the treatment of MRSA is complicated by biofilms, the lead combinations successfully inhibited biofilm formation and also demonstrated biofilm disruption potential. Encouragingly, the peptides alone and in combination were able to elicit in vivo anti-MRSA activity and reduce the bacterial load in the liver and kidney of immune-compromised mice. Importantly, the presence of Ana-peptides at sub-MIC doses slowed the resistance development against oxacillin in MRSA cells. Thus, this study highlights the synergistic activity of Ana-peptides with oxacillin advocating for the potential of Ana-peptides as an alternative therapeutic and could pave the way for the reintroduction of less potent conventional antibiotics into clinical use against MRSA infections.


Assuntos
Antibacterianos , Staphylococcus aureus Resistente à Meticilina , Animais , Camundongos , Antibacterianos/farmacologia , Oxacilina/farmacologia , Biofilmes , Peptídeos/farmacologia , Hormônios Estimuladores de Melanócitos
5.
Qual Quant ; 56(3): 1245-1259, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34092816

RESUMO

Globalization has led to an increasing emphasis on the critical role of the workforce in the success of organizations. This has resulted in the shift of focus on human resource development (HRD) as the center of attention in the current paradigm. Hence, this article suggests a need to use a comprehensive philosophical paradigm to develop practical theories in HRD and compares the usefulness of positivism, interpretivism and pragmatism philosophies in the theory-building process. Based on fragmented literature in philosophy and HRD disciplines, this theoretical manuscript has assembled and thoroughly reviewed the existing literature to propose new ways of theory building in HRD. The findings guide that despite the usefulness of positivism and interpretivism philosophical paradigms in knowledge generation, these philosophies lead to practically weak theories. Hence, theory building in HRD should be driven by a problem-solving approach rather than only relying on plausibility criteria. It further guides how multi-method and mixed-method research designs might help provide answers to complex and newly emerged challenges in HRD. Overall, this research adds value to a body of knowledge by proposing a unique five-stage framework to develop new theories in HRD using the pragmatism approach. The use of the proposed framework might be beneficial in developing practically and theoretically useful theories in the future.

6.
ACS Infect Dis ; 8(12): 2480-2493, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36440863

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA), a biofilm-forming recalcitrant pathogen with a multidrug-resistant profile, poses a pandemic threat to human health and is the leading cause of severe infections in both healthcare and community settings. In this study, toward designing novel α-MSH-based peptides with enhanced activity and stability against MRSA, particularly its stationary phase and biofilm, we explored a design approach to augment the hydrophobicity of an 8-mer C-terminal α-MSH(6-13)-based peptide Ana-5 through the incorporation of a bulky unnatural amino acid. The designed Ana-peptides overcame the limitation of diminished activity in biological media and exhibited enhanced antistaphylococcal activity and cell selectivity. With membrane rupture as the primary mode of action, the peptides exhibited inhibitory potential against S. aureus biofilms. Importantly, the peptides did not exhibit any adverse effects in the in vivo toxicity studies and were also able to significantly alleviate bacterial infection in a systemic infection mice model study. Additionally, the peptides retained their activity in the presence of serum and displayed a low propensity toward resistance development in MRSA cells. Moreover, the observed synergistic potential of Ana-10 with conventional antibiotics could be vital in resurrecting discarded antibiotics. Thus, this study provides us with an exciting lead, Ana-10, for further development against biofilm-based chronic S. aureus infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , beta-Lactamas , Humanos , Animais , Camundongos , alfa-MSH , Staphylococcus aureus
7.
Basic Clin Pharmacol Toxicol ; 128(3): 503-510, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33190395

RESUMO

Gabapentinoids are substrate of L-type amino acid transporter 1 (LAT1) for distribution across the blood-brain barrier. The present study aimed to evaluate the effect of LAT1 rs4240803 genetic polymorphism on the clinical efficacy and tolerability of gabapentinoids in Pakistani patients with neuropathic pain. Three-hundred and ninety-two patients were recruited, genotyped for SNP rs4240803, and followed up for eight weeks to evaluate the clinical response to gabapentinoids in terms of pain relief, inadequate response, and the emergence of adverse events. LAT1 rs4240803 GG, GA, and AA genotype frequency were 33.42%, 47.96% and 18.62%, respectively. Out of 392 patients, 323 responded to the treatment and 17.6% discontinued either due to insufficient response or intolerable adverse events (AEs). GA genotype was more frequent in non-responder group (P Ë‚ 0.001). Maximum pain responders (≥50%) in combination with the lowest incidence of AEs were observed in the GG group, whereas partial responders belonged to GA genotype and with the highest frequency of somnolence (83.6%) and dizziness (69.9%). Overall, 72.5% patients with GA genotype experienced AEs (P Ë‚ 0.001). In conclusion, clinical outcomes of gabapentinoids are influenced by LAT1 rs4240803 polymorphism and population pharmacogenetics should be considered to evaluate the maximum potential of gabapentinoids in the management of neuropathic pain.


Assuntos
Gabapentina/uso terapêutico , Transportador 1 de Aminoácidos Neutros Grandes/genética , Neuralgia/tratamento farmacológico , Polimorfismo de Nucleotídeo Único , Adulto , Feminino , Gabapentina/efeitos adversos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Neuralgia/genética
8.
ACS Omega ; 5(44): 28425-28440, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33195893

RESUMO

Stationary phase Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA), has been widely associated with many persistent infections as well as biofilm-associated infections, which are challenging due to their increasing antibiotic resistance. α-Melanocyte stimulating hormone (α-MSH) is an antimicrobial peptide (AMP) with well-established potent activity against S. aureus , but little is known about its antimicrobial efficacy against the stationary phase of the bacteria. We investigated the in vitro activities of two palmitoylated analogues, Pal-α-MSH(6-13) and Pal-α-MSH(11-13), of the C-terminal fragments of α-MSH against biofilm-producing strains of methicillin-sensitive S. aureus (MSSA) and MRSA. While both the peptides demonstrated anti-staphylococcal efficacy, Pal-α-MSH(11-13) emerged as the most effective AMP as palmitoylation led to a remarkable enhancement in its activity against stationary phase bacteria. Similar to α-MSH, both the designed analogues were membrane-active and exhibited improved bacterial membrane depolarization and permeabilization, as further confirmed via electron microscopy studies. Of the two peptides, Pal-α-MSH(11-13) was able to retain its activity in the presence of standard microbiological media, which otherwise is a major limiting factor toward the therapeutic use of α-MSH-based peptides. More importantly, Pal-α-MSH(11-13) was also highly effective in inhibiting the formation of biofilms. Furthermore, it did not lead to resistance development in MRSA cells even upon 18 serial passages at sub-MIC concentrations. These observations support the potential use of Pal-α-MSH(11-13) in the treatment of planktonic as well as sessile S. aureus infections.

9.
ACS Omega ; 5(7): 3258-3270, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32118141

RESUMO

Antimicrobial peptides (AMPs), an essential component of innate immunity, are very important resources for human therapeutics to counter the current threat of drug resistance. We have previously established that one such AMP, α-melanocyte stimulating hormone (α-MSH), an endogenous neuropeptide, and its derivatives have potent antimicrobial activity against Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA). However, the immense potential of α-MSH for therapeutic development against staphylococcal infections is marred by its reduced efficacy in the presence of standard microbiological culture medium. To overcome this issue, in this study, we designed a series of five novel analogues of the C-terminal fragment of α-MSH, i.e., α-MSH(6-13), by replacing uncharged and less hydrophobic residues with tryptophan and arginine to increase the hydrophobicity and cationic charge of the peptide, respectively. While all of the peptides showed a preferential interaction with negatively charged phospholipid vesicles, the most hydrophobic and cationic peptide, i.e., Ana-5, exhibited the highest activity against S. aureus cells while maintaining cell selectivity. Moreover, Ana-5 could retain its activity even in complex media like the Mueller Hinton broth and displayed rapid bactericidal activity in the presence of serum. Ana-5 also caused rapid bacterial membrane depolarization, permeabilization, and cell lysis and was able to bind to polyanionic plasmid DNA suggesting a possible dual mode of action of the peptide. Importantly, Ana-5 was able to eradicate intracellular S. aureus in fibroblast cells similar to conventional antibiotics. Collectively, in the present study, we obtained a potent α-MSH-based analogue with excellent staphylocidal potency in microbial growth medium and ex vivo efficacy, which may translate into therapeutic application.

10.
Cureus ; 11(5): e4723, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31355083

RESUMO

Objectives There are many different ways to measure body composition and bioelectric impedance is one of the most popular methods to measure body ratios. The navy-seal formula is another simple way of measuring body fat ratio which takes into account simple variables such as gender, weight, height, waist, hip and neck circumference. The objective of our study was to compare the results of body fat composition by these two methods. Materials and methods Height and weight were measured in 85 study participants using a wall-mounted stadiometer and digital scale. Body composition measurements were recorded using a simple measuring tape. Participants were then asked to stand on the electrical impedance machine to determine the body fat and muscle mass. Data were analyzed on IBM's statistical package for the social sciences (SPSS) version 23 (IBM, Armonk, NY). Results The Navy-seal formula had slightly higher values for both muscle mass and body fat ratio in both genders and across all body mass index (BMI) categories. Body fat ratio and muscle mass of both genders were similar in underweight, normal, over weight and obese participants. In males, the results on two instruments showed more similarity with the increase in BMI, whereas, in females, the results of the two methods were more similar in the normal weight category. Conclusion Navy-seal formula and bioelectrical impedance are both simple and reliable instruments to measure body composition in adults. The navy-seal formula can be used to screen individuals with high-fat body fat ratio whereas bioelectric impedance can be used to measure the body composition for personal monitoring.

11.
Sci Rep ; 8(1): 1021, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-29348589

RESUMO

Escalating multidrug resistance and highly evolved virulence mechanisms have aggravated the clinical menace of methicillin-resistant Staphylococcus aureus (MRSA) infections. Towards development of economically viable staphylocidal agents here we report eight structurally novel tryptophan-arginine template based peptidomimetics. Out of the designed molecules, three lipopeptidomimetics (S-6, S-7 and S-8) containing 12-amino dodecanoic acid exhibited cell selectivity and good to potent activity against clinically relevant pathogens MRSA, methicillin-resistant Staphylococcus epidermidis and vancomycin-resistant Enterococcus faecium (MIC: 1.4-22.7 µg/mL). Mechanistically, the active peptidomimetics dissipated membrane potential and caused massive permeabilization on MRSA concomitant with loss of viability. Against stationary phase MRSA under nutrient-depleted conditions, active peptidomimetics S-7 and S-8 achieved > 6 log reduction in viability upon 24 h incubation while both S-7 (at 226 µg/mL) and S-8 (at 28 µg/mL) also destroyed 48 h mature MRSA biofilm causing significant decrease in viability (p < 0.05). Encouragingly, most active peptidomimetic S-8 maintained efficacy against MRSA in presence of serum/plasma while exhibiting no increase in MIC over 17 serial passages at sub-MIC concentrations implying resistance development to be less likely. Therefore, we envisage that the current template warrants further optimization towards the development of cell selective peptidomimetics for the treatment of device associated MRSA infections.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Biofilmes/efeitos dos fármacos , Lipopeptídeos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Plâncton/efeitos dos fármacos , Animais , Peptídeos Catiônicos Antimicrobianos/síntese química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Biomimética , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Sintética , Desenho de Fármacos , Lipopeptídeos/síntese química , Lipopeptídeos/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/ultraestrutura , Camundongos , Testes de Sensibilidade Microbiana , Fatores de Tempo
12.
Sci Rep ; 6: 31492, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27526963

RESUMO

The steady rise in antimicrobial resistance poses a severe threat to global public health by hindering treatment of an escalating spectrum of infections. We have previously established the potent activity of α-MSH, a 13 residue antimicrobial peptide, against the opportunistic pathogen Staphylococcus aureus. Here, we sought to determine whether an increase in cationic charge in α-MSH could contribute towards improving its staphylocidal potential by increasing its interaction with anionic bacterial membranes. For this we designed novel α-MSH analogues by replacing polar uncharged residues with lysine and alanine. Similar to α-MSH, the designed peptides preserved turn/random coil conformation in artificial bacterial mimic 1,2-dimyristoyl-sn-glycero-3-phosphocholine:1,2-dimyristoyl-sn-glycero-3-phospho-rac-(1-glycerol) (7:3, w/w) vesicles and showed preferential insertion in the hydrophobic core of anionic membranes. Increased cationic charge resulted in considerable augmentation of antibacterial potency against MSSA and MRSA. With ~18-fold better binding than α-MSH to bacterial mimic vesicles, the most charged peptide KKK-MSH showed enhanced membrane permeabilization and depolarization activity against intact S. aureus. Scanning electron microscopy confirmed a membrane disruptive mode of action for KKK-MSH. Overall, increasing the cationic charge improved the staphylocidal activity of α-MSH without compromising its cell selectivity. The present study would help in designing more effective α-MSH-based peptides to combat clinically relevant staphylococcal infections.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Cátions/metabolismo , Metabolismo dos Lipídeos , Staphylococcus aureus/efeitos dos fármacos , alfa-MSH/química , alfa-MSH/farmacologia , Antibacterianos/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Ligação Proteica , Relação Estrutura-Atividade , alfa-MSH/metabolismo
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