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1.
Angew Chem Int Ed Engl ; 63(3): e202314028, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38029352

RESUMEN

The caseinolytic protease is a highly conserved serine protease, crucial to prokaryotic and eukaryotic protein homeostasis, and a promising antibacterial and anticancer drug target. Herein, we describe the potent cystargolides as the first natural ß-lactone inhibitors of the proteolytic core ClpP. Based on the discovery of two clpP genes next to the cystargolide biosynthetic gene cluster in Kitasatospora cystarginea, we explored ClpP as a potential cystargolide target. We show the inhibition of Staphylococcus aureus ClpP by cystargolide A and B by different biochemical methods in vitro. Synthesis of semisynthetic derivatives and probes with improved cell penetration allowed us to confirm ClpP as a specific target in S. aureus cells and to demonstrate the anti-virulence activity of this natural product class. Crystal structures show cystargolide A covalently bound to all 14 active sites of ClpP from S. aureus, Aquifex aeolicus, and Photorhabdus laumondii, and reveal the molecular mechanism of ClpP inhibition by ß-lactones, the predominant class of ClpP inhibitors.


Asunto(s)
Dipéptidos , Staphylococcus aureus , Staphylococcus aureus/metabolismo , Dominio Catalítico , Dipéptidos/metabolismo , Virulencia , Endopeptidasa Clp/metabolismo
2.
Mol Cell Biochem ; 2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37410210

RESUMEN

Genetic polymorphisms of apolipoprotein B gene (APOB) may result into serum proteomic perturbance in Coronary Artery Disease (CAD). The current case-control cohort of Pakistani subjects was designed to analyze the genetic influence of APOB rs1042031, (G/T) genotype on serum proteome. Subjects were categorized into two groups: CAD patients (n = 480) and healthy individuals (n = 220). For genotyping, tetra ARMS-PCR was carried out and validated through sequencing, whereas LC/MS-based proteomic analysis of serum samples was performed through label-free quantification. In initial step of genotyping, the frequencies of each genotype GG, GT, and TT were 70%, 27%, and 30% in CAD patients, while in control group, the subjects were 52%, 43%, and 5%, respectively, in CAD patients. The genotypic frequencies in patients vs. control groups found significantly different (p = 0.004), and a strong association of dominant alleles GG with the CAD was observed in both dominant (OR: 2.4 (1.71-3.34), p = 0.001) and allelic genetic models (OR: 2.0 (1.45-2.86), p = 0.001). In second step of label-free quantitation, a total of 40 significant proteins were found with altered expression in CAD patients. The enriched Gene Ontology (GO) terms of molecular functions and pathways of these protein showed upregulated pathways as follows: chylomicron remodeling and assembly, complement cascade activation, plasma lipoprotein assembly, apolipoprotein-A receptor binding, and metabolism of fat-soluble vitamins in G allele carrier of rs1042031 (G > T) vs. mutant T-allele carriers. This study provides better understanding of CAD pathobiology by proteogenomics of APOB. It evidences the influence of APOB rs1042031-dominant (GG) genotype with CAD patients.

3.
Bioorg Chem ; 130: 106175, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36410112

RESUMEN

Alzheimer's disease (AD), a relentless neurodegenerative disorder, is still waiting for safer profile drugs, risk factors affecting AD's pathogenesis include aß accumulation, tau protein hyperphosphorylation, and neuroinflammation. This research aimed to synthesize 2-amino-6­trifluoromethoxy benzothiazole schiff bases. Synthesis was straightforward, combining the riluzole skeleton with compounds containing the azomethine group. Schiff bases synthesized were characterized spectroscopically using proton NMR (1H NMR), and FTIR. In-vivo biological evaluation against scopolamine-induced neuronal damage revealed that these newly synthesized schiff bases were effective in protecting neurons against neuroinflammatory mediators. In-vitro results revealed that these compounds had remarkable potential in improving the anti-oxidant levels. It downregulated glutathione (GSH), glutathione S-transferase (GST), catalase levels, and upregulated lipid peroxidation (LPO) levels. Immunohistochemical studies revealed that groups treated with the newly synthesized schiff bases had reduced expression of inflammatory mediators such as cyclooxygenase 2 (COX-2), JNK, tumor necrosis factor (TNF-α), nuclear factor kappa B (NF-kB) in contrast to the disease group. Moreover, molecular docking studies on these compounds also showed that they possessed a better binding affinity for above mentioned inflammatory mediators. The results of these studies showed that 2-amino-6-trifluoromethoxy benzothiazole schiff bases are remarkably effective against oxidative stress-mediated neuroinflammation.


Asunto(s)
Benzotiazoles , Bases de Schiff , Antioxidantes/farmacología , Benzotiazoles/farmacología , Mediadores de Inflamación , Simulación del Acoplamiento Molecular , Bases de Schiff/química , Riluzol/química , Riluzol/farmacocinética
4.
Int J Mol Sci ; 23(1)2021 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-35008890

RESUMEN

The Clp protease system fulfills a plethora of important functions in bacteria. It consists of a tetradecameric ClpP barrel holding the proteolytic centers and two hexameric Clp-ATPase rings, which recognize, unfold, and then feed substrate proteins into the ClpP barrel for proteolytic degradation. Flexible loops carrying conserved tripeptide motifs protrude from the Clp-ATPases and bind into hydrophobic pockets (H-pockets) on ClpP. Here, we set out to engineer microcin J25 (MccJ25), a ribosomally synthesized and post-translationally modified peptide (RiPP) of the lasso peptide subfamily, by introducing the conserved tripeptide motifs into the lasso peptide loop region to mimic the Clp-ATPase loops. We studied the capacity of the resulting lasso peptide variants to bind to ClpP and affect its activity. From the nine variants generated, one in particular (12IGF) was able to activate ClpP from Staphylococcus aureus and Bacillus subtilis. While 12IGF conferred stability to ClpP tetradecamers and stimulated peptide degradation, it did not trigger unregulated protein degradation, in contrast to the H-pocket-binding acyldepsipeptide antibiotics (ADEPs). Interestingly, synergistic interactions between 12IGF and ADEP were observed.


Asunto(s)
Bacillus subtilis , Endopeptidasa Clp , Staphylococcus aureus , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Endopeptidasa Clp/genética , Endopeptidasa Clp/metabolismo , Proteolisis , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
5.
Chembiochem ; 21(14): 1997-2012, 2020 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-32181548

RESUMEN

Acyldepsipeptide (ADEP) is an exploratory antibiotic with a novel mechanism of action. ClpP, the proteolytic core of the caseinolytic protease, is deregulated towards unrestrained proteolysis. Here, we report on the mechanism of ADEP resistance in Firmicutes. This bacterial phylum contains important pathogens that are relevant for potential ADEP therapy. For Staphylococcus aureus, Bacillus subtilis, enterococci and streptococci, spontaneous ADEP-resistant mutants were selected in vitro at a rate of 10-6 . All isolates carried mutations in clpP. All mutated S. aureus ClpP proteins characterised in this study were functionally impaired; this increased our understanding of the mode of operation of ClpP. For molecular insights, crystal structures of S. aureus ClpP bound to ADEP4 were determined. Well-resolved N-terminal domains in the apo structure allow the pore-gating mechanism to be followed. The compilation of mutations presented here indicates residues relevant for ClpP function and suggests that ADEP resistance will occur at a lower rate during the infection process.


Asunto(s)
Antibacterianos/farmacología , Depsipéptidos/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Endopeptidasa Clp/antagonistas & inhibidores , Firmicutes/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/química , Depsipéptidos/química , Endopeptidasa Clp/metabolismo , Firmicutes/enzimología , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Mutación , Staphylococcus aureus/enzimología
7.
Mol Microbiol ; 101(2): 194-209, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26919556

RESUMEN

The Clp protease complex in Mycobacterium tuberculosis is unusual in its composition, functional importance and activation mechanism. Whilst most bacterial species contain a single ClpP protein that is dispensable for normal growth, mycobacteria have two ClpPs, ClpP1 and ClpP2, which are essential for viability and together form the ClpP1P2 tetradecamer. Acyldepsipeptide antibiotics of the ADEP class inhibit the growth of Gram-positive firmicutes by activating ClpP and causing unregulated protein degradation. Here we show that, in contrast, mycobacteria are killed by ADEP through inhibition of ClpP function. Although ADEPs can stimulate purified M. tuberculosis ClpP1P2 to degrade larger peptides and unstructured proteins, this effect is weaker than for ClpP from other bacteria and depends on the presence of an additional activating factor (e.g. the dipeptide benzyloxycarbonyl-leucyl-leucine in vitro) to form the active ClpP1P2 tetradecamer. The cell division protein FtsZ, which is a particularly sensitive target for ADEP-activated ClpP in firmicutes, is not degraded in mycobacteria. Depletion of the ClpP1P2 level in a conditional Mycobacterium bovis BCG mutant enhanced killing by ADEP unlike in other bacteria. In summary, ADEPs kill mycobacteria by preventing interaction of ClpP1P2 with the regulatory ATPases, ClpX or ClpC1, thus inhibiting essential ATP-dependent protein degradation.


Asunto(s)
Depsipéptidos/uso terapéutico , Endopeptidasa Clp/efectos de los fármacos , Endopeptidasa Clp/metabolismo , Adenosina Trifosfatasas/metabolismo , Antibacterianos/farmacología , Proteínas Bacterianas/efectos de los fármacos , Proteínas Bacterianas/metabolismo , Depsipéptidos/química , Depsipéptidos/farmacología , Endopeptidasa Clp/fisiología , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/metabolismo , Péptido Hidrolasas/metabolismo , Proteolisis , Serina Endopeptidasas/metabolismo
8.
PLoS One ; 19(6): e0301597, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38861525

RESUMEN

This research investigates the complex interaction between liquidity and volatility while considering Economic Policy Uncertainty (EPU) as a moderating factor. Using a comprehensive dataset that incorporates various liquidity measures such as market resilience, depth, and breadth, the study examines how changes in liquidity impact volatility in four Asian incipient economies: China, Pakistan, India, and South Korea. By utilizing sophisticated econometric techniques, particularly the System Generalized Method of Moment (GMM), the findings demonstrate a statistically significant inverse relationship between liquidity and volatility. These findings imply that, within the Asian context, lower levels of volatility are correlated with higher market liquidity. By incorporating EPU into the model, the research acknowledges the significant role of economic factors in shaping market dynamics. Stakeholders, decision-makers, and investors can gain valuable insights from this analysis of variables influencing market stability in Asian emerging economies. The study's outcomes can guide policymakers in formulating strategies that promote market stability and improve market microstructure.


Asunto(s)
Modelos Económicos , Incertidumbre , Humanos , India , China , Pakistán , República de Corea , Asia , Comercio/economía , Inversiones en Salud/economía , Modelos Econométricos
9.
Chem Asian J ; : e202400320, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38838273

RESUMEN

Hydrogen (H2) is being acknowledged as the future energy carrier due to its high energy density and potential to mitigate the intermittency of other renewable energy sources. H2 also ensures a clean, carbon-neutral, and sustainable environment for current and forthcoming generations by contributing to the global missions of decarbonization in the transportation, industrial, and building sectors. Several H2 storage technologies are available and have been employed for its secure and economical transport. The existing H2 storage and transportation technologies like liquid-state, cryogenic, or compressed hydrogen are in use but still suffer from significant challenges regarding successful realization at the commercial level. These factors affect the overall operational cost of technology. Therefore, H2 storage demands novel technologies that are safe for mobility, transportation, long-term storage, and yet it is cost-effective. This review article presents potential opportunities for H2 storage technologies, such as physical and chemical storage. The prime characteristics and requirements of H2 storage are briefly explained. A detailed discussion of chemical-based hydrogen storage systems such as metal hydrides, chemical hydrides (CH3OH, NH3, and HCOOH), and liquid organic hydrogen carriers (LOHCs) is presented. Furthermore, the recent developments and challenges regarding hydrogen storage, their real-world applications, and prospects have also been debated.

10.
Genes (Basel) ; 14(2)2023 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-36833368

RESUMEN

Hepatitis is one of the common liver diseases, imposing a heavy health burden worldwide. Acute hepatitis may develop into chronic hepatitis, progressing to cirrhosis and hepatocellular carcinoma. In the present study, the expression of miRNAs was quantified by real-time PCR, such as miRNA-182, 122, 21, 150, 199, and 222. Along with the control group, HCV was divided into chronic, cirrhosis, and HCC groups. The treated group was also included after the successful treatment of HCV. Biochemical parameters, such as ALT, AST, ALP, bilirubin, viral load, and AFP (HCC), were also evaluated in all of the study groups. We compared the control and diseased groups; these parameters showed significant results (p = 0.000). The viral load was high in HCV but was not detected after treatment. miRNA-182 and miRNA-21 were overexpressed with disease progression, while the expression of miRNA-122 and miRNA-199 was increased compared with the control, but decreased in the cirrhosis stage compared with chronic and HCC. The expression of miRNA-150 was increased in all of the diseased groups compared with the control, but decreased compared with the chronic group. We compared the chronic and treated groups and then all of these miRNAs were down-regulated after treatment. These microRNAs could be used as potential biomarkers for diagnosing different stages of HCV.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis C , Neoplasias Hepáticas , MicroARNs , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Pakistán , Cirrosis Hepática
11.
Genes (Basel) ; 14(2)2023 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-36833442

RESUMEN

The intake of various types and amounts of dietary fats influences metabolic and cardiovascular health. Hence, this study evaluated the impact of routinely consumed Pakistani dietary fats on their cardiometabolic impact. For this, we made four groups of mice, each comprising 5 animals: (1) C-ND: Control mice on a normal diet, (2) HFD-DG: High-fat diet mice on a normal diet plus 10% (w/w) desi ghee, (3) HFD-O: Mice on normal diet plus 10% (w/w) plant oil (4) HFD-BG: Mice on normal diet plus 10% (w/w) banaspati ghee. Mice were fed for 16 weeks, and blood, liver, and heart samples were collected for biochemical, histological, and electron microscopic analysis. The physical factors indicated that mice fed on HFD gained more body weight than the C-ND group. Blood parameters do not show significant differences, but overall, the glucose and cholesterol concentrations were raised in the mice fed with a fat-rich diet, with the highest concentrations in the HFD-BG group. The mice fed with HFD-BG and HFD-O had more lipid droplets in the liver, compared to HFD-DG and C-ND.


Asunto(s)
Ghee , Ratones , Animales , Hígado/metabolismo , Peso Corporal , Grasas de la Dieta/metabolismo , Dieta Alta en Grasa
12.
Heliyon ; 9(9): e19779, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37809765

RESUMEN

The current study explores the potential of melatonin (MLT)-loaded solid lipid nanoparticles (MLT-SLNs) for better neuroprotective effects in ischemic stroke. MLT-SLNs were prepared using lipid matrix of palmityl alcohol with a mixture of surfactants (Tween 40, Span 40, Myrj 52) for stabilizing the lipid matrix. MLT-SLNs were tested for physical and chemical properties, thermal and polymorphic changes, in vitro drug release and in vivo neuroprotective studies in rats using permanent middle cerebral artery occlusion (p-MCAO) model. The optimized MLT-SLNs showed particle size of ∼159 nm, zeta potential of -29.6 mV and high entrapment efficiency ∼92%. Thermal and polymorphic studies showed conversion of crystalline MLT to amorphous form after its entrapment in lipid matrix. MLT-SLNs displayed a sustained release pattern compared to MLT dispersion. MLT-SLNs significantly enhanced the neuroprotective profile of MLT ascertained by reduced brain infarction, recovered behavioral responses, low expression of inflammatory markers and improved oxidation protection in rats. MLT-SLNs also showed reduced hepatotoxicity compared to p-MCAO. From these outcomes, it is evidenced that MLT-SLNs have improved neuroprotection as compared to MLT dispersion and thereby present a promising approach to deliver MLT to the brain for better therapeutic outcomes in ischemic stroke.

13.
Scand J Infect Dis ; 44(1): 55-9, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21933033

RESUMEN

A major problem in chronic hepatitis B virus (HBV) infection is that treatment with specific antivirals is life-long since they rarely induce a sustained response. An attractive option is therefore to combine antiviral therapy with some type of immune stimulator, such as a therapeutic vaccine. Several lines of evidence suggest that a key target for the cellular immune response is the HBV core antigen (HBcAg). However, it may also be of advantage to simultaneously improve the neutralizing antibody response to the surface (S) region of HBV. We therefore generated chimeric HBcAg particles expressing preS1 residues 1-42 at the tip of the spike region. We could show that this chimeric HBcAg-preS1 protein primed both HBcAg-specific T cells and antibodies to preS1. This strongly suggests that this may be a viable approach to develop an effective bi-functional therapeutic vaccine as an add-on for the treatment of chronic HBV infections.


Asunto(s)
Antígenos del Núcleo de la Hepatitis B/uso terapéutico , Antígenos de Superficie de la Hepatitis B/uso terapéutico , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/tratamiento farmacológico , Linfocitos T/inmunología , Vacunación/métodos , Animales , Anticuerpos Neutralizantes , Femenino , Antígenos del Núcleo de la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/inmunología , Hepatitis B Crónica/inmunología , Inmunidad Celular/inmunología , Ratones , Ratones Endogámicos C57BL , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/uso terapéutico
14.
Front Pharmacol ; 13: 936161, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36052146

RESUMEN

This present study aims to delineate Rumex dentatus crude extract (Rd.Cr), n-Hexane, ethyl acetate, aqueous fractions (Rd.n-Hex, Rd.ETAC, and Rd.Aq), and emodin for antidiarrheal, antisecretory effects, anti-spasmodic, gastrointestinal transient time, anti-H. pylori, antiulcer effects, and toxicology. Plant extracts attributed dose-dependent protection against castor oil-induced diarrhea and dose-dependently inhibited intestinal fluid secretions in mice. They decreased the distance transverse by charcoal in the gastrointestinal transit model in rats. In rabbit jejunum preparations, it causes a concentration-dependent relaxation of both spontaneous and K+ (80 mM)-induced contraction, Rd.n-Hex and verapamil were relatively potent against K+-induced contractions and shifted the Ca2+ concentration-response curves (CRCs) to the right, Rd.Cr and Rd.ETAC shifted the isoprenaline-induced inhibitory CRCs to the left, showing potentiating effect similar to papaverine. Rd.n-Hex showed anti-H. pylori effect. Extracts and emodin also show an inhibitory effect against H+/K+-ATPase. Rumex dentatus showed a gastroprotective and antioxidant effect. Histopathological evaluation showed improvement in cellular architecture and decrease in the expression of inflammatory markers such as cyclooxygenase (COX2), tumor necrosis factor (TNF-α), and phosphorylated nuclear factor kappa B (p-NFƙB), validated through immunohistochemistry, ELISA, and western blot techniques. In RT-PCR, it decreases H+/K+-ATPase mRNA levels. Rumex dentatus was analyzed for certain safety aspects and exhibited a relative safety profile as no impairment was observed in kidneys, heart, liver, and brain further assisted by biochemical and hematological analysis. Docking studies revealed that emodin against H+/K+-ATPase pump and voltage gated L-type calcium channel showed E-value of -7.9 and -7.4 kcal/mol, respectively. MD simulations and molecular mechanics Poisson Boltzmann surface area and molecular mechanics Generalized Born surface area MMPBSA/GBSA findings are consistent with the in-vitro, in-vivo, and docking results. In conclusion, Rumex dentatus extracts and its phytoconstituent could be considered a potent antioxidant and anti-inflammatory drug candidates that possess anti-diarrheal, anti-secretary, antispasmodic, anti-H. pylori, and anti-ulcer potential. Toxicity studies were done according to OECD standards 425. It belongs to group 5 (LD50 > 2000 mg/kg), which suggests that it is in the lower toxicity class.

15.
Colloids Surf B Biointerfaces ; 216: 112537, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35561634

RESUMEN

The present study was intended to prepare and optimize agomelatine-loaded nanostructured lipid carriers (AGM-NLCs) for augmented in vivo antidepressant potential. AGM-NLCs were optimized on several parameters including cumulative hydrophilic-lipophilic balance of surfactants, proportions of solid and liquid lipids, total amounts of drug and surfactants. AGM-NLCs were assessed for their physicochemical properties, in vitro AGM release and in vivo antidepressant effects in mice model. The optimized AGM-NLCs demonstrated spherical morphology with average particle size of 99.8 ± 2.6 nm, PDI of 0.142 ± 0.017, zeta potential of - 23.2 ± 1.2 mV and entrapment efficiency of 97.1 ± 2.1%. Thermal and crystallinity studies depict amorphous nature of AGM after its incorporation into NLCs. AGM-NLCs exhibit a sustained drug release profile after initial 2 h. Mice treated with AGM-NLCs exhibited reduced immobility time in behavioral analysis. Furthermore, cresyl violet staining demonstrated an improved neuronal morphology and survival in AGM-NLCs group. The concentrations and the expression of inflammatory markers (TNF-α and COX-2) in mice brain were significantly reduced by AGM-NLCs. Taken together, therapeutic effectiveness of AGM was markedly augmented in AGM-NLCs and thereby they could be promising nanocarriers for the effective delivery of antidepressants to brain.


Asunto(s)
Portadores de Fármacos , Nanoestructuras , Acetamidas , Animales , Antidepresivos/farmacología , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Lípidos/química , Ratones , Nanoestructuras/química , Naftalenos , Tamaño de la Partícula , Tensoactivos/química
16.
Microbiol Spectr ; 10(5): e0256722, 2022 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-36173303

RESUMEN

Resistance to antibiotics is an increasing problem and necessitates novel antibacterial therapies. The polyketide antibiotics cervimycin A to D are natural products of Streptomyces tendae HKI 0179 with promising activity against multidrug-resistant staphylococci and vancomycin-resistant enterococci. To initiate mode of action studies, we selected cervimycin C- and D-resistant (CmR) Staphylococcus aureus strains. Genome sequencing of CmR mutants revealed amino acid exchanges in the essential histidine kinase WalK, the Clp protease proteolytic subunit ClpP or the Clp ATPase ClpC, and the heat shock protein DnaK. Interestingly, all characterized CmR mutants harbored a combination of mutations in walK and clpP or clpC. In vitro and in vivo analyses showed that the mutations in the Clp proteins abolished ClpP or ClpC activity, and the deletion of clpP rendered S. aureus but not all Bacillus subtilis strains cervimycin-resistant. The essential gene walK was the second mutational hotspot in the CmR S. aureus strains, which decreased WalK activity in vitro and generated a vancomycin-intermediate resistant phenotype, with a thickened cell wall, a lower growth rate, and reduced cell lysis. Transcriptomic and proteomic analyses revealed massive alterations in the CmR strains compared to the parent strain S. aureus SG511, with major shifts in the heat shock regulon, the metal ion homeostasis, and the carbohydrate metabolism. Taken together, mutations in the heat shock genes clpP, clpC, and dnaK, and the walK kinase gene in CmR mutants induced a vancomycin-intermediate resistant phenotype in S. aureus, suggesting cell wall metabolism or the Clp protease system as primary target of cervimycin. IMPORTANCE Staphylococcus aureus is a frequent cause of infections in both the community and hospital setting. Resistance development of S. aureus to various antibiotics is a severe problem for the treatment of this pathogen worldwide. New powerful antimicrobial agents against Gram-positives are needed, since antibiotics like vancomycin fail to cure vancomycin-intermediate resistant S. aureus (VISA) and vancomycin-resistant enterococci (VRE) infections. One candidate substance with promising activity against these organisms is cervimycin, which is an antibiotic complex with a yet unknown mode of action. In our study, we provide first insights into the mode of action of cervimycins. By characterizing cervimycin-resistant S. aureus strains, we revealed the Clp system and the essential kinase WalK as mutational hotspots for cervimycin resistance in S. aureus. It further emerged that cervimycin-resistant S. aureus strains show a VISA phenotype, indicating a role of cervimycin in perturbing the bacterial cell envelope.


Asunto(s)
Productos Biológicos , Staphylococcus aureus Resistente a Meticilina , Policétidos , Infecciones Estafilocócicas , Humanos , Vancomicina/farmacología , Vancomicina/metabolismo , Staphylococcus aureus/metabolismo , Staphylococcus aureus Resistente a Meticilina/genética , Endopeptidasa Clp/genética , Endopeptidasa Clp/metabolismo , Resistencia a la Vancomicina/genética , Histidina Quinasa/genética , Histidina Quinasa/metabolismo , Proteómica , Pruebas de Sensibilidad Microbiana , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Fenotipo , Policétidos/metabolismo , Aminoácidos/metabolismo
17.
Toxics ; 10(11)2022 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-36355948

RESUMEN

The synthesis of a photo-catalyst with a narrow bandgap and efficient capability to degrade contaminants in the presence of sunlight is currently challenging but exciting. In this work, an efficient photocatalytic ternary nanocomposite g-C3N4/Cu@CdS has been synthesized successfully by using the co-precipitation method. The synthesized composite was then characterized by SEM, XRD studies, EDX analysis, and ultra-violet-visible (UV-VIS) spectroscopy. The catalytic efficiency for the methylene blue (MB) dye and drug degradation (ciprofloxacin) was assessed by UV-visible absorption spectra. Gram-positive and Gram-negative bacteria were used to test the fabrication composite's antibacterial properties. Various compositions (1%, 3%, 5%, 7%, and 9%) of/Cu@CdS nanocomposite (NCs) and 20%, 30%, 40%, 50%, and 60% of g-C3N4 NCs were prepared. Results reveal that 5%Cu@CdS and 40%g-C3N45%Cu@CdS showed maximum antibacterial activity and photocatalytic degradation of dye and drug. The X-ray pattern showed no remarkable change in doped and pristine CdS nanoparticles (NPs). The efficient photocatalytic degradation activity of the fabricated ternary nanocomposite against MB dye and ciprofloxacin an antibiotic drug makes it a viable contender for solving environmental problems.

18.
Sci Rep ; 11(1): 22766, 2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34815491

RESUMEN

In the current study, APOB (rs1052031) genotype-guided proteomic analysis was performed in a cohort of Pakistani population. A total of 700 study subjects, including Coronary Artery Disease (CAD) patients (n = 480) and healthy individuals (n = 220) as a control group were included in the study. Genotyping was carried out by using tetra primer-amplification refractory mutation system-based polymerase chain reaction (T-ARMS-PCR) whereas mass spectrometry (Orbitrap MS) was used for label free quantification of serum samples. Genotypic frequency of GG genotype was found to be 90.1%, while 6.4% was for GA genotype and 3.5% was for AA genotypes in CAD patients. In the control group, 87.2% healthy subjects were found to have GG genotype, 11.8% had GA genotype, and 0.9% were with AA genotypes. Significant (p = 0.007) difference was observed between genotypic frequencies in the patients and the control group. The rare allele AA was found to be strongly associated with the CAD [OR: 4 (1.9-16.7)], as compared to the control group in recessive genetic model (p = 0.04). Using label free proteomics, altered expression of 60 significant proteins was observed. Enrichment analysis of these protein showed higher number of up-regulated pathways, including phosphatidylcholine-sterol O-acyltransferase activator activity, cholesterol transfer activity, and sterol transfer activity in AA genotype of rs562338 (G>A) as compared to the wild type GG genotype. This study provides a deeper insight into CAD pathobiology with reference to proteogenomics, and proving this approach as a good platform for identifying the novel proteins and signaling pathways in relation to cardiovascular diseases.


Asunto(s)
Apolipoproteína B-100/genética , Enfermedad de la Arteria Coronaria/patología , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Proteogenómica/métodos , Proteoma/metabolismo , Adulto , Anciano , Estudios de Casos y Controles , Enfermedad de la Arteria Coronaria/genética , Enfermedad de la Arteria Coronaria/metabolismo , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Proteoma/análisis , Factores de Riesgo
19.
J Coll Physicians Surg Pak ; 20(1): 37-41, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20141691

RESUMEN

OBJECTIVE: To assess the local wound complications in complicated/ high risk laparotomies in terms of wound dehiscence and incisional hernia formation with a modified technique of midline abdominal wound closure. STUDY DESIGN: Quasi-experimental study. PLACE AND DURATION OF STUDY: Department of General Surgery, Combined Military Hospital, Bahawal Nagar Cantonment, May 2006 to June 2008. METHODOLOGY: Cases of complicated/high risk abdominal conditions, which required laparotomy, were included in the study. A modified midline abdominal wound closure technique was used. Interrupted Smead-Jones sutures with prolene, a non-absorbable suture material for closure of linea alba was combined with mass closure involving all the layers (also with prolene) and drains were placed. Patients were followed-up for 3-23 months. The postoperative wound dehiscence and incisional hernia formation were noted. Other local wound complications were also recorded. RESULTS: Out of the 36 patients undergoing this surgical technique, 20 (55.55%) had inflammatory/intra-abdominal sepsis, 8 (22.22%) had trauma, 7 (19.44%) had neoplasia and 1 (2.77%) had vascular aetiology. Only 1 (2.77%) had partial wound dehiscence and 1 (2.77%) developed incisional hernia. Wound infection was noted in 12 (33.33%) cases; 4 (11.11%) experienced pain over the subcutaneous palpable knots and 3 (8.33%) developed sinus due to the knots. The average follow-up period was 12.47+7.17 months. CONCLUSION: Patients with extensive widespread generalized peritonitis and metastatic abdominal tumours need special attention regarding wound closure. This modified technique of midline abdominal wound closure is associated with low incidence of wound dehiscence and incisional hernia formation.


Asunto(s)
Abdomen/cirugía , Neoplasias Abdominales/cirugía , Enfermedades del Sistema Digestivo/cirugía , Laparotomía/métodos , Adolescente , Adulto , Anciano , Femenino , Hernia Abdominal/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Peritonitis/cirugía , Dehiscencia de la Herida Operatoria/prevención & control , Técnicas de Sutura , Adulto Joven
20.
Dose Response ; 18(3): 1559325820958911, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32973419

RESUMEN

Nano-fertilizer(s), an emerging field of agriculture, is alternate option for enhancement of plant growth replacing the synthetic fertilizers. Zinc oxide nanoparticles (ZnO NPs) can be used as the zinc source for plants. The present investigation was carried out to assess the role of ZnO NPs in growth promotion of maize plants. Biosynthesized ZnO NPs (using Bacillus sp) were characterized using Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), X-ray diffraction (XRD) and Zeta potential. Different concentrations of ZnO NPs (2, 4, 8, 16 mg/L) were explored in pot culture experiment. Size of ZnO NPs ranged between 16 and 20 nm. A significant increase in growth parameters like shoot length (61.7%), root length (56.9%) and significantly higher level of protein was observed in the treated plants. The overall pattern for growth biomarkers including the protein contents was maximum at 8 mg/L of ZnO NPs. It was observed that application of biosynthesized ZnO NPs has improved majority of growth biomarkers including plant growth parameters, protein contents and leaf area. Therefore, biosynthesized ZnO NPs could be considered as an alternate source of nutrient in Zn deficient soils for promoting the modern agriculture.

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