DNA fingerprints were established in 12 drug resistant and 12 susceptible M. tuberculosis strains collected from patients residing in Prague, Czech Republic. The Restriction Fragment Length Polymorphism (RFLP) technique was based on the detection of the insertion sequence IS6110 in PvuII digested chromosomal DNA. All investigated strains possessed at least 5 copies of IS6110 ranging from 5 to 15 copies in the drug resistant isolates and 5 to 11 copies in susceptible isolates. Three multidrug resistant strains displayed identical fingerprints (5 bands), and two strains resistant to pyrazinamid had the same banding pattern (12 bands). The remaining isolates differed either in number or location of the IS6110 copies. Thorough epidemiological analysis did not furnish proof of direct contact among these patients.

• MeSH
• antibiotická rezistence genetika   MeSH
• antituberkulotika farmakologie   MeSH
• DNA bakterií genetika   MeSH
• DNA fingerprinting * MeSH
• lidé MeSH
• multirezistentní tuberkulóza mikrobiologie   MeSH
• Mycobacterium tuberculosis klasifikace   účinky léků   genetika   MeSH
• polymorfismus délky restrikčních fragmentů * MeSH
• techniky typizace bakterií MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Československo MeSH
• Názvy látek
• antituberkulotika MeSH
• DNA bakterií MeSH

Epigallocatechin gallate (EGCG), the major catechin contained in tea leaves, is known to possess the synergistic anti-staphylococcal activity in combination with various β-lactam antibiotics and tetracycline. In the present study, we explored the in vitro combinatory effect of EGCG in combination with oxytetracycline against eight standard strains and clinical isolates of Staphylococcus aureus, including erythromycin, methicillin and tetracycline resistant strains. The minimum inhibitory concentrations were determined by the broth microdilution assay and the data were evaluated according to the sum of fractional inhibitory concentrations (∑FIC). Our results showed synergistic and additive interactions against all S. aureus strains tested (∑FIC 0.288-0.631), two of which were multidrug resistant. According to our best knowledge, it is the first report on the EGCG synergy with oxytetracycline. Considering its significant synergistic antimicrobial effect and low toxicity, we suggest EGCG as a promising compound for the development of new anti-staphylococcal formulations.

• MeSH
• antibakteriální látky farmakologie   MeSH
• čaj chemie   MeSH
• erythromycin farmakologie   MeSH
• katechin analogy a deriváty   farmakologie   MeSH
• listy rostlin chemie   MeSH
• methicilin rezistentní Staphylococcus aureus účinky léků   MeSH
• mikrobiální testy citlivosti MeSH
• mnohočetná bakteriální léková rezistence MeSH
• oxytetracyklin farmakologie   MeSH
• rezistence na methicilin MeSH
• rezistence na tetracyklin MeSH
• synergismus léků MeSH
• tetracyklin farmakologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antibakteriální látky MeSH
• čaj MeSH
• epigallocatechin gallate MeSH Prohlížeč
• erythromycin MeSH
• katechin MeSH
• oxytetracyklin MeSH
• tetracyklin MeSH

BACKGROUND: Antiviral resistance development is a serious complication of human cytomegalovirus virostatic therapy caused by mutations in UL 97 and/or UL54 genes. OBJECTIVES: To determinate the presence of sensitive and resistant strains in patients developing antiviral resistance. STUDY DESIGN: We used three different molecular biological methods for mutation analysis-restriction fragment length polymorphism, sequencing and real-time PCR approach. RESULTS: We describe three allogeneic hematopoietic stem cell transplant patients developing the GCV resistant HCMV strains manifested by virostatic treatment failure. In these patients we identified UL97 mutations L595S, A594V and A594T and monitored the dynamics of coexisted sensitive/resistant strains. We confirmed the presence of mixed HCMV populations and in two patients a phenomenon of sensitive strain repopulation which occurred after 6.5 months and 1 month after removing GCV pressure. CONCLUSIONS: Our results show changes in proportions of sensitive/resistant subpopulations over time but other studies would be required to demonstrate the beneficial impact of their monitoring on clinical outcome.

• Klíčová slova
• HCMV resistance, Real-time PCR, Repopulation, Sensitive/resistant strain,
• MeSH
• antivirové látky terapeutické užití   MeSH
• cytomegalovirové infekce farmakoterapie   virologie   MeSH
• Cytomegalovirus účinky léků   genetika   izolace a purifikace   MeSH
• diagnostické techniky molekulární metody   MeSH
• dospělí MeSH
• homologní transplantace škodlivé účinky   MeSH
• kvantitativní polymerázová řetězová reakce metody   MeSH
• lidé středního věku MeSH
• lidé MeSH
• missense mutace * MeSH
• neúspěšná terapie MeSH
• polymorfismus délky restrikčních fragmentů MeSH
• sekvenční analýza DNA MeSH
• transplantace hematopoetických kmenových buněk škodlivé účinky   MeSH
• virová léková rezistence * MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antivirové látky MeSH

Protease inhibitors (PIs) are an important class of drugs for the treatment of HIV infection. However, in the course of treatment, resistant viral variants with reduced sensitivity to PIs often emerge and become a major obstacle to successful control of viral load. On the basis of a compound equipotently inhibiting HIV-1 and 2 proteases (PR), we have designed a pseudopeptide inhibitor, QF34, that efficiently inhibits a wide variety of PR variants. In order to analyze the potency of the inhibitor, we constructed PR species harboring the typical (signature) mutations that confer resistance to commercially available PIs. Kinetic analyses showed that these mutated PRs were inhibited up to 1,000-fold less efficiently by the clinically approved PIs. In contrast, all PR species were effectively inhibited by QF34. In a clinical study, we have monitored 30 HIV-positive patients in the Czech Republic undergoing highly active antiretroviral therapy, and have identified highly PI resistant variants. Kinetic analyses revealed that QF34 retained its subnanomolar potency against multi-drug resistant PR variants. X-ray crystallographic analysis and molecular modeling experiments explained the wide specificity of QF34: this inhibitor binds to the PR in an unusual manner, thus avoiding contact sites that are mutated upon resistance development, and the unusual binding mode and consequently the binding energy is therefore preserved in the complex with a resistant variant. These results suggest a promising route for the design of second-generation PIs that are active against a variety of resistant PR variants.

• MeSH
• antibiotická rezistence genetika   MeSH
• genotyp MeSH
• HIV infekce farmakoterapie   virologie   MeSH
• HIV-1 účinky léků   genetika   metabolismus   MeSH
• inhibitory HIV-proteasy chemie   metabolismus   farmakologie   MeSH
• inhibitory reverzní transkriptasy farmakologie   MeSH
• kinetika MeSH
• konformace proteinů MeSH
• krystalografie rentgenová MeSH
• lidé MeSH
• mnohočetná léková rezistence genetika   MeSH
• molekulární konformace MeSH
• molekulární modely MeSH
• molekulární struktura MeSH
• mutace MeSH
• oligopeptidy chemie   metabolismus   farmakologie   MeSH
• proteinové inženýrství MeSH
• racionální návrh léčiv MeSH
• rekombinantní proteiny chemie   izolace a purifikace   metabolismus   MeSH
• substituce aminokyselin MeSH
• vazebná místa MeSH
• vysoce aktivní antiretrovirová terapie MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• inhibitory HIV-proteasy MeSH
• inhibitory reverzní transkriptasy MeSH
• oligopeptidy MeSH
• QF34 pseudopeptide MeSH Prohlížeč
• rekombinantní proteiny MeSH

Tuberculosis (TB) remains a major global health concern, particularly due to the emergence of multidrug-resistant (MDR) Mycobacterium tuberculosis strains. While previous studies have suggested andrographolide as a potential antimycobacterial agent based on in silico predictions, limited empirical evidence exists on its direct efficacy against MDR-TB. This study systematically evaluates the antimycobacterial activity of andrographolide through the microbroth dilution method against M. tuberculosis H37Rv and three distinct MDR strains. The minimum inhibitory concentrations (MICs) were determined using Middlebrook 7H9 medium, with rifampicin and isoniazid as positive controls. Andrographolide completely inhibited M. tuberculosis H37Rv at an MIC of 125 µg/mL, while MICs for MDR strains varied (500 µg/mL, 125 µg/mL, and 250 µg/mL for MDR-Isolates 1, 2, and 3, respectively). Unlike previous studies that primarily relied on computational docking models, our findings provide direct experimental validation of andrographolide's strain-specific efficacy, demonstrating its potential as a promising lead compound for anti-tubercular drug development. These results underscore the need for further preclinical investigations to explore its therapeutic applications in combating drug-resistant TB.

• Klíčová slova
• Andrographolide, Antimycobacterial, Minimum inhibitory concentration, Multidrug-resistant, Tuberculosis,
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Severe Acinetobacter baumannii infections in immunocompetent patients are uncommon, and the virulence mechanisms of this organism are not fully understood. METHODS: Following an outbreak of fatal A. baumannii infections in a cohort of relatively immunocompetent patients (low comorbidity and illness severity scores), isolates were investigated with comparative genomics and in animal models. RESULTS: Two unrelated A. baumannii clades were associated with the outbreak. The clone associated with the majority of patient deaths, clade B, is evolutionarily distinct from the 3 international clonal complexes, belongs to multilocus sequence type (MLST) 10, and is most closely related to strains isolated from the Czech Republic, California, and Germany in 1994, 1997, and 2003, respectively. In 2 different murine models, clade B isolates were more virulent than comparator strains, including the highly virulent reference strain AB5075. The most virulent clade B derivative, MRSN 16897, was isolated from the patient with the lowest combined comorbidity/illness severity score. Clade B isolates possess a unique combination of putative virulence genes involved in iron metabolism, protein secretion, and glycosylation, which was leveraged to develop a rapid and specific clinical assay to detect this clade that cannot be distinguished by MLST. CONCLUSIONS: Clade B warrants continued surveillance and investigation.

• Klíčová slova
• Acinetobacter baumannii, extensively drug resistant, outbreak, virulence,
• MeSH
• Acinetobacter baumannii klasifikace   genetika   izolace a purifikace   patogenita   MeSH
• centra terciární péče statistika a číselné údaje   MeSH
• dospělí MeSH
• epidemický výskyt choroby * MeSH
• fylogeneze MeSH
• genomika MeSH
• imunokompetence MeSH
• infekce bakteriemi rodu Acinetobacter epidemiologie   genetika   mikrobiologie   mortalita   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mnohočetná bakteriální léková rezistence * genetika   MeSH
• modely nemocí na zvířatech MeSH
• multilokusová sekvenční typizace MeSH
• myši MeSH
• senioři nad 80 let MeSH
• virulence genetika   MeSH
• zvířata MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• senioři nad 80 let MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Geografické názvy
• Česká republika MeSH
• Kalifornie MeSH
• Německo MeSH
• Spojené státy americké epidemiologie   MeSH

DNA fingerprinting based on the detection of the insertion sequence IS6110 in Pvull restriction fragments was applied to M. tuberculosis isolates originating in the first microepidemic of multidrug resistant tuberculosis recorded in the Czech Republic. Their disseminators were 21 individuals living in--or roaming between three distant areas. The age of 17 males ranged from 36 to 64 years (average 45 years) and of 4 females aged from 38 to 52 years. The index person was most probably a former male prisoner, aged 49 years, who disseminated multidrug resistant M. tuberculosis over a period of 28 months. In ten of the patients the following risk factors for tuberculosis were found: imprisonment, homelessness, immigration and previous stay in asylum--or in a psychiatric ward. In six cases, M. kansasii infection preceded tuberculosis. Four out of the 21 patients died. The RFLP analysis separated the patients into two distinct groups: group A comprising 14 members of which M. tuberculosis strains were isolated with six IS6110 copies, whereas the isolates of seven individuals of the group B, the RFLP profile displayed highly similar RFLP patterns compared to the isolates of group A, but with two additional IS6110 copies. In one patient, both A and B patterns were found: the first one in a M. tuberculosis strain isolated in 1993 and the second one in the isolate isolated two years later. Both the appearance of pattern B among the isolates of a part of patients and the switch from A to B pattern in one of patients can be plausibly explained by the unstability of DNA genotypes caused by transposition of IS6110 elements.

• MeSH
• antituberkulotika terapeutické užití   MeSH
• DNA fingerprinting MeSH
• dospělí MeSH
• epidemický výskyt choroby * MeSH
• isoniazid terapeutické užití   MeSH
• lidé středního věku MeSH
• lidé MeSH
• multirezistentní tuberkulóza farmakoterapie   epidemiologie   mikrobiologie   MeSH
• Mycobacterium tuberculosis účinky léků   genetika   izolace a purifikace   MeSH
• polymorfismus délky restrikčních fragmentů MeSH
• rifampin terapeutické užití   MeSH
• rizikové faktory MeSH
• sexuální faktory MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Názvy látek
• antituberkulotika MeSH
• isoniazid MeSH
• rifampin MeSH

AIM: Europe has the highest documented caseload and greatest increase in multidrug and extensively drug-resistant tuberculosis (M/XDR-TB) of all World Health Organization (WHO) regions. This survey examines how recommendations for M/XDR-TB management are being implemented. METHODS: TBNET is a pan-European clinical research collaboration for tuberculosis. An email survey of TBNET members collected data in relation to infection control, access to molecular tests and basic microbiology with drug sensitivity testing. RESULTS: 68/105 responses gave valid information and were from countries within the WHO European Region. Inpatient beds matched demand, but single rooms with negative pressure were only available in low incidence countries; ultraviolet decontamination was used in 5 sites, all with >10 patients with M/XDR-TB per year. Molecular tests for mutations associated with rifampicin resistance were widely available (88%), even in lower income and especially in high incidence countries. Molecular tests for other first line and second line drugs were less accessible (76 and 52% respectively). A third of physicians considered that drug susceptibility results were delayed by > 2 months. CONCLUSION: Infection control for inpatients with M/XDR-TB remains a problem in high incidence countries. Rifampicin resistance is readily detected, but tests to plan regimens tailored to the drug susceptibilities of the strain of Mycobacterium tuberculosis are significantly delayed, allowing for further drug resistance to develop.

• Klíčová slova
• Drug-resistance, Europe, Infection control, PCR, Tuberculosis,
• MeSH
• antituberkulotika terapeutické užití   MeSH
• bakteriální léková rezistence genetika   MeSH
• dekontaminace metody   MeSH
• extenzivně rezistentní tuberkulóza diagnóza   farmakoterapie   MeSH
• izolace pacientů metody   MeSH
• kontrola infekce metody   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• multirezistentní tuberkulóza diagnóza   farmakoterapie   MeSH
• Mycobacterium tuberculosis genetika   MeSH
• průzkumy a dotazníky MeSH
• rifampin terapeutické užití   MeSH
• rozvojové země MeSH
• ultrafialové záření MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Evropa MeSH
• Názvy látek
• antituberkulotika MeSH
• rifampin MeSH

Multidrug-resistant (MDR) Staphylococcus aureus infections significantly threaten global health. With rising resistance to current antibiotics and limited solutions, the urgent discovery of new, effective, and affordable antibacterials with low toxicity is imperative to combat diverse MDR S. aureus strains. Hence, in this study, we introduce an in silico phytochemical-based approach for discovering novel antibacterial agents, underscoring the potential of computational approaches in therapeutic discovery. Glucomoringin Isothiocyanate (GMG-ITC) from Moringa oleifera Lam. is one of the phytochemical compounds with several biological activities, including antimicrobial, anti-inflammatory, and antioxidant activities, and is also effective against S. aureus. This study focuses on screening GMG-ITC as a potential drug candidate to combat MDR S. aureus infections through a molecular docking approach. Moreover, interaction amino acid analysis, in silico pharmacokinetics, compound target prediction, pathway enrichment analysis and molecular dynamics (MD) simulations were conducted for further investigation. Molecular docking and interaction analysis showed strong binding affinity towards S. aureus lipase, dihydrofolate reductase, and other MDR S. aureus proteins, including penicillin-binding protein 2a, MepR, D-Ala:D-Ala ligase, and RPP TetM, through hydrophilic and hydrophobic interactions. GMG-ITC also showed a strong binding affinity to cyclooxygenase-2 and FAD-dependent NAD(P)H oxidase, suggesting that it is a potential anti-inflammatory and antioxidant candidate that may eliminate inflammation and oxidative stress associated with S. aureus infections. MD simulations validated the stability of the GMG-ITC molecular interactions determined by molecular docking. In silico pharmacokinetic analysis highlights its potency as a drug candidate, showing strong absorption, distribution, and excretion properties in combination with low toxicity. It acts as an active protease and enzyme inhibitor with moderate activity against GPCR ligands, ion channels, nuclear receptor ligands, and kinases. Enrichment analysis further elucidated its involvement in important biological, molecular, and cellular functions with potential therapeutic applications in diseases like cancer, hepatitis B, and influenza. Results suggest that GMG-ITC is an effective antibacterial agent that could treat MDR S. aureus-associated infections.

• Klíčová slova
• GO and KEGG enrichment pathway, Glucomoringin isothiocyanate, In silico pharmacokinetic analysis, MD simulation, Molecular docking, Multi-drug resistance,
• MeSH
• antibakteriální látky * chemie   farmakologie   MeSH
• bakteriální proteiny antagonisté a inhibitory   chemie   metabolismus   MeSH
• fytonutrienty chemie   farmakologie   MeSH
• isothiokyanatany * chemie   farmakologie   MeSH
• lidé MeSH
• methicilin rezistentní Staphylococcus aureus účinky léků   MeSH
• mnohočetná bakteriální léková rezistence účinky léků   MeSH
• Moringa oleifera chemie   MeSH
• objevování léků MeSH
• počítačová simulace MeSH
• simulace molekulární dynamiky MeSH
• simulace molekulového dockingu * MeSH
• Staphylococcus aureus účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antibakteriální látky * MeSH
• bakteriální proteiny MeSH
• benzyl isothiocyanate MeSH Prohlížeč
• fytonutrienty MeSH
• isothiokyanatany * MeSH

Carbonyl-reducing enzymes (CREs) catalyse the reduction of carbonyl groups in many eobiotic and xenobiotic compounds in all organisms, including helminths. Previous studies have shown the important roles of CREs in the deactivation of several anthelmintic drugs (e.g., flubendazole and mebendazole) in adults infected with the parasitic nematode Haemonchus contortus, in which the activity of a CRE is increased in drug-resistant strains. The aim of the present study was to compare the abilities of nematodes of both a drug-susceptible strain (ISE) and a drug-resistant strain (IRE) to reduce the carbonyl group of flubendazole (FLU) in different developmental stages (eggs, L1/2 larvae, L3 larvae, and adults). In addition, the effects of selected CRE inhibitors (e.g., glycyrrhetinic acid, naringenin, silybin, luteolin, glyceraldehyde, and menadione) on the reduction of FLU were evaluated in vitro and ex vivo in H. contortus adults. The results showed that FLU was reduced by H. contortus in all developmental stages, with adult IRE females being the most metabolically active. Larvae (L1/2 and L3) and adult females of the IRE strain reduced FLU more effectively than those of the ISE strain. Data from the in vitro inhibition study (performed with cytosolic-like fractions of H. contortus adult homogenate) revealed that glycyrrhetinic acid, naringenin, mebendazole and menadione are effective inhibitors of FLU reduction. Ex vivo study data showed that menadione inhibited FLU reduction and also decreased the viability of H. contortus adults to a similar extent. Naringenin and mebendazole were not toxic at the concentrations tested, but they did not inhibit the reduction of FLU in adult worms ex vivo.

• Klíčová slova
• Anthelmintics, Strongyloides, drug biotransformation, helminths, inhibitors,
• MeSH
• anthelmintika * farmakologie   terapeutické užití   MeSH
• Haemonchus * MeSH
• kyselina glycyrhetinová * farmakologie   MeSH
• larva MeSH
• mebendazol farmakologie   terapeutické užití   MeSH
• vitamin K 3 farmakologie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• anthelmintika * MeSH
• flubendazole MeSH Prohlížeč
• kyselina glycyrhetinová * MeSH
• mebendazol MeSH
• vitamin K 3 MeSH