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A strain belonging to the genus Psychrobacter, named PraFG1T, was isolated from the peritoneal effusion of a stray dog during necropsy procedures. The strain was characterized by the phylogenetic analyses based on the nucleotide sequences of 16S and 23S rRNA genes and of gyrB, which placed the strain in the genus Psychrobacter. The nucleotide sequence of the chromosome confirmed the placement, showing an average nucleotide identity of 72.1, 77.7, and 77.5â% with the closest related species, namely Psychrobacter sanguinis, Psychrobacter piechaudii, and Psychrobacter phenylpyruvicus, respectively, thus indicating a novel species. The polyphasic characterization by biochemical and fatty acid profiling as well as MALDI-TOF supported those findings. The strain was halotolerant, capable of growing within a temperature range between 4 and 37â°C, it was positive for catalase and oxidase, indole producing, nitrate reducing, and not able to use 5-keto-d-gluconic acid as a carbon source. Taken together, the data suggest that strain PraFG1T could be considered as representing a novel species, with the name Psychrobacter raelei sp. nov. (type strain PraFG1T=CIP 111873T=LMG 32233T).
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Técnicas de Tipificación Bacteriana , ADN Bacteriano , Ácidos Grasos , Peritonitis , Filogenia , Psychrobacter , ARN Ribosómico 16S , ARN Ribosómico 23S , Análisis de Secuencia de ADN , Animales , Psychrobacter/genética , Psychrobacter/aislamiento & purificación , Psychrobacter/clasificación , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Peritonitis/microbiología , Perros , ARN Ribosómico 23S/genética , Enfermedades de los Perros/microbiología , Infecciones por Bacterias Grampositivas/microbiologíaRESUMEN
West Nile virus (WNV) is a public health concern in Europe. Rising temperatures and the migration of potential vectors promote the spread of viruses to previously unaffected areas. In 2023, the Apulia region of Southern Italy experienced an unexpected increase in West Nile neuroinvasive disease (WNND); no such cases had been reported in the previous 10 years. Overall, eight autochthonous cases of WNV infection were identified between July and October 2023, six of which were WNND. All cases were male (median age, 73 years). Two of the cases were blood donors. All WNND cases were hospitalized and all recovered within a few weeks. Surveillance data showed that, in the Apulia region, WNV Lineage 2 was detected in humans, mosquitoes, and horses. Based on the number of WNND cases reported, we can assume that a high number of infections occurred during the summer period. Changes in the climate in the region over recent years could be considered among the main drivers of the rapid increase in WNV infections. Therefore, integrated surveillance should be strengthened to avoid the potential massive spread of WNV in Southern Italy. Moreover, the implementation of whole-genome sequencing of WNV strains, as well as seroepidemiological studies in the area, will facilitate a better understanding of circulation dynamics.
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Fiebre del Nilo Occidental , Virus del Nilo Occidental , Humanos , Masculino , Animales , Caballos , Anciano , Femenino , Fiebre del Nilo Occidental/epidemiología , Virus del Nilo Occidental/genética , Mosquitos Vectores , Italia/epidemiología , Europa (Continente)RESUMEN
Introduction: Brucellosis is a widespread zoonosis of great economic importance for livestock farming in many areas of the world. It is a highly infectious disease which is diagnosed using conventional serological and microbiological methods. The aim of this study was to assess the efficiency of a specific real-time PCR in combination with broth cultivation in detecting Brucella spp. in organs of infected cattle, in order to compare the sensitivity of the two approaches and the time needed in them until a correct diagnosis is made. Material and Methods: We examined 67 organs collected from 10 cattle slaughtered following a brucellosis outbreak which occurred in February 2016 in southern Italy. The research was carried out by enrichment broth cultivations in combination with a real-time PCR every week for six weeks. Results: Brucella strains were isolated by cultivation from 44 enrichment broths of organs. All isolates were later identified as Brucella abortus by real-time PCR. Using this method in combination with cultivation made it possible to identify the same percentage of infected animals faster than by cultivation alone. Moreover, the same diagnostic results were obtained, on average two weeks before they would have been using only cultivation. In almost all cases, Brucella was detected by real-time PCR after the first week of cultivation in pre-enrichment Brucella broth, while the bacterial growth was evident usually after 2 or 3 weeks. Conclusion: Real-time PCR has allowed results to be obtained faster than in the classical microbiological method, reducing the response times to identify positive animals by half.
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In the last century, the exponential increase of industrial food production led to the disappearance of "Italian traditional niche products". However, national regulations allowed the preservation of several of these products, including the burrata cheese. Twenty-one samples from three different batches of "Burrata di Andria" Protected Geographical Indication (PGI) were purchased from dairy factories of the PGI consortium. Moisture value of PGI Burrata cheese was significantly higher than that before the PGI release. Moreover, a significantly lower NaCl value was detected in PGI raw milk Burrata cheeses with respect to non-PGI ones, while an opposite situation was detected in pasteurized milk Burrata cheeses. As for pH, in all PGI products lower values were observed with respect to non-PGI products, which resulted significant only in pasteurized ones. No Salmonella spp., Listeria monocytogenes, and Bacillus cereus were detected, while nine samples were positive for a nonpathogenic strain of Yersinia enterocolitica. Total viable count (TVC) and Escherichia coli resulted significantly lower in pasteurized than in raw milk PGI Burrata cheese samples. Although samples analyzed can be considered microbiologically safe, these were borderline and/or unsatisfactory for E. Coli and coagulase-positive staphylococci (CPS) according to process hygiene criteria established by European regulation. Therefore, different strategies should be adopted to improve products hygiene in the considered dairy factories.
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This report describes the evolution of COVID-19 in a 10 day-old-baby. The mother developed the disease immediately after childbirth and therefore a vertical transmission can be excluded. The isolation of the virus in cell culture with a cytopathic effect already visible after 48 h, indicates that the viral load of the newborn was quite high, but not serious course of the disease was observed. This paper wants to highlight the possible role of newborns and children in the spread of the disease.
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Three series of azole piperazine derivatives that mimic dicyclotyrosine (cYY), the natural substrate of the essential Mycobacterium tuberculosis cytochrome P450 CYP121A1, were prepared and evaluated for binding affinity and inhibitory activity (MIC) against M. tuberculosis. Series A replaces one phenol group of cYY with a C3-imidazole moiety, series B includes a keto group on the hydrocarbon chain preceding the series A imidazole, whilst series C explores replacing the keto group of the piperidone ring of cYY with a CH2-imidazole or CH2-triazole moiety to enhance binding interaction with the heme of CYP121A1. The series displayed moderate to weak type II binding affinity for CYP121A1, with the exception of series B 10a, which displayed mixed type I binding. Of the three series, series C imidazole derivatives showed the best, although modest, inhibitory activity against M. tuberculosis (17d MICâ¯=â¯12.5⯵g/mL, 17a 50⯵g/mL). Crystal structures were determined for CYP121A1 bound to series A compounds 6a and 6b that show the imidazole groups positioned directly above the haem iron with binding between the haem iron and imidazole nitrogen of both compounds at a distance of 2.2â¯Å. A model generated from a 1.5â¯Å crystal structure of CYP121A1 in complex with compound 10a showed different binding modes in agreement with the heterogeneous binding observed. Although the crystal structures of 6a and 6b would indicate binding with CYP121A1, the binding assays themselves did not allow confirmation of CYP121A1 as the target.
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Antituberculosos/farmacología , Azoles/farmacología , Dipéptidos/farmacología , Diseño de Fármacos , Mycobacterium tuberculosis/efectos de los fármacos , Péptidos Cíclicos/farmacología , Piperazinas/farmacología , Antituberculosos/síntesis química , Antituberculosos/química , Azoles/química , Sitios de Unión/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/metabolismo , Dipéptidos/química , Relación Dosis-Respuesta a Droga , Ligandos , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Estructura Molecular , Mycobacterium tuberculosis/metabolismo , Péptidos Cíclicos/química , Piperazina , Piperazinas/química , Relación Estructura-ActividadRESUMEN
Three series of biarylpyrazole imidazole and triazoles are described, which vary in the linker between the biaryl pyrazole and imidazole/triazole group. The imidazole and triazole series with the short -CH2- linker displayed promising antimycobacterial activity, with the imidazole-CH2- series (7) showing low MIC values (6.25-25 µg/mL), which was also influenced by lipophilicity. Extending the linker to -C(O)NH(CH2)2- resulted in a loss of antimycobacterial activity. The binding affinity of the compounds with CYP121A1 was determined by UV-visible optical titrations with KD values of 2.63, 35.6, and 290 µM, respectively, for the tightest binding compounds 7e, 8b, and 13d from their respective series. Both binding affinity assays and docking studies of the CYP121A1 inhibitors suggest type II indirect binding through interstitial water molecules, with key binding residues Thr77, Val78, Val82, Val83, Met86, Ser237, Gln385, and Arg386, comparable with the binding interactions observed with fluconazole and the natural substrate dicyclotyrosine.
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Inhibidores Enzimáticos del Citocromo P-450/química , Inhibidores Enzimáticos del Citocromo P-450/farmacología , Sistema Enzimático del Citocromo P-450/química , Mycobacterium tuberculosis/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/química , Antituberculosos/química , Antituberculosos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Sitios de Unión , Cristalografía por Rayos X , Inhibidores Enzimáticos del Citocromo P-450/síntesis química , Sistema Enzimático del Citocromo P-450/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Pirazoles/química , Bibliotecas de Moléculas Pequeñas/farmacología , Espectrofotometría UltravioletaRESUMEN
Tuberculosis, caused by Mycobacterium tuberculosis (Mtb), is the infectious disease responsible for the highest number of deaths worldwide. Herein, 22 new N-oxide-containing compounds were synthesized followed by in vitro and in vivo evaluation of their antitubercular potential against Mtb. Compound 8 was found to be the most promising compound, with MIC90 values of 1.10 and 6.62 µM against active and nonreplicating Mtb, respectively. Additionally, we carried out in vivo experiments to confirm the safety and efficacy of compound 8; the compound was found to be orally bioavailable and highly effective, leading to a reduction of Mtb to undetectable levels in a mouse model of infection. Microarray-based initial studies on the mechanism of action suggest that compound 8 blocks translation. Altogether, these results indicate that benzofuroxan derivative 8 is a promising lead compound for the development of a novel chemical class of antitubercular drugs.
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Antituberculosos/química , Antituberculosos/farmacología , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/farmacología , Animales , Antituberculosos/síntesis química , Antituberculosos/farmacocinética , Disponibilidad Biológica , Células CACO-2 , Compuestos Heterocíclicos/síntesis química , Compuestos Heterocíclicos/farmacocinética , Humanos , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/efectos de los fármacos , Óxidos/química , Análisis Espectral/métodosRESUMEN
The burrata cheese is a traditional product from Southern Italy, consisting of an envelope of pasta filata (stretched curd) filled with cream and pasta filata strips (usually leftovers from mozzarella production). Physical [water activity (aw), pH], chemical (moisture, NaCl content) and microbiological [total viable count (TVC), Listeria monocytogenes, Salmonella spp., Yersinia enterocolitica, Bacillus cereus, Escherichia coli, Enterobacteriaceae, coagulase-positive staphylococci] characteristics of burrata cheeses manufactured in artisanal and industrial plants were evaluated. The artisanal burrata showed lower aw values in the filling and the final product. The same was recorded in the filling for the moisture, probably due to differences between the types of cream used in the artisanal and the industrial cheesemaking. The pH value of the filling differed between the two groups but no difference was recorded in the final product. Microbiological differences were also recorded, with higher values for TVC and E. coli in artisanal than industrial burrata. All samples were negative for the other microbial determinations, with the exception of coagulase-positive staphylococci and Y. enterocolitica, which were detected in artisanal burrata. Differences in cheesemaking process were probably responsible for the strong variability of the physical and chemical data between the two cheeses; furthermore, differences in the hygienic features were also recorded. Even though artisanal products showed lower aw and pH values and higher NaCl concentration, the higher E. coli loads highlighted the need for a more accurate compliance with hygienic procedures along the artisanal cheesemaking process.
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Tuberculosis (TB) remains a serious health problem responsible to cause millions of deaths annually. The scenario becomes alarming when it is evaluated that the number of new drugs does not increase proportionally to the emergence of resistance to the current therapy. Furoxan derivatives, known as nitric oxide (NO) donors, have been described to exhibit antitubercular activity. Herein, a novel series of hybrid furoxan derivatives (1,2,5-oxadiazole 2-N-oxide) (compounds 4a-c, 8a-c and 14a-c) were designed, synthesized and evaluated in vitro against Mycobacterium tuberculosis (MTB) H37Rv (ATCC 27294) and a clinical isolate MDR-TB strain. The furoxan derivatives have exhibited MIC90 values ranging from 1.03 to 62 µM (H37Rv) and 7.0-50.0 µM (MDR-TB). For the most active compounds (8c, 14a, 14b and 14c) the selectivity index ranged from 3.78 to 52.74 (MRC-5 cells) and 1.25-34.78 (J774A.1 cells). In addition, it was characterized for those compounds logPo/w values between 2.1 and 2.9. All compounds were able to release NO at levels ranging from 0.16 to 44.23%. Among the series, the phenylsulfonyl furoxan derivatives (compounds 14a-c) were the best NO-donor with the lowest MIC90 values. The most active compound (14c) was also stable at different pHs (5.0 and 7.4). In conclusion, furoxan derivatives were identified as new promising compounds useful to treat tuberculosis.
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Antituberculosos/síntesis química , Antituberculosos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Oxadiazoles/síntesis química , Oxadiazoles/farmacología , Antituberculosos/química , Antituberculosos/toxicidad , Línea Celular Tumoral , Técnicas de Química Sintética , Diseño de Fármacos , Humanos , Oxadiazoles/química , Oxadiazoles/toxicidadRESUMEN
The mechanisms that lead to phenotypic antibacterial tolerance in bacteria remain poorly understood. We investigate whether changes in NaCl concentration toward physiologically higher values affect antibacterial efficacy against Mycobacterium tuberculosis (Mtb), the causal agent of human tuberculosis. Indeed, multiclass phenotypic antibacterial tolerance is observed during Mtb growth in physiologic saline. This includes changes in sensitivity to ethionamide, ethambutol, d-cycloserine, several aminoglycosides, and quinolones. By employing organism-wide metabolomic and lipidomic approaches combined with phenotypic tests, we identified a time-dependent biphasic adaptive response after exposure of Mtb to physiological levels of NaCl. A first rapid, extensive, and reversible phase was associated with changes in core and amino acid metabolism. In a second phase, Mtb responded with a substantial remodelling of plasma membrane and outer lipid membrane composition. We demonstrate that phenotypic tolerance at physiological concentrations of NaCl is the result of changes in plasma and outer membrane lipid remodeling and not changes in core metabolism. Altogether, these results indicate that physiologic saline-induced antibacterial tolerance is kinetically coupled to cell envelope changes and demonstrate that metabolic changes and growth arrest are not the cause of phenotypic tolerance observed in Mtb exposed to physiologic concentrations of NaCl. Importantly, this work uncovers a role for bacterial cell envelope remodeling in antibacterial tolerance, alongside well-documented allterations in respiration, metabolism, and growth rate.
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The essential enzyme CYP121 is a target for drug development against antibiotic resistant strains of Mycobacterium tuberculosis. A triazol-1-yl phenol fragment 1 was identified to bind to CYP121 using a cascade of biophysical assays. Synthetic merging and optimization of 1 produced a 100-fold improvement in binding affinity, yielding lead compound 2 (KD = 15 µM). Deconstruction of 2 into its component retrofragments allowed the group efficiency of structural motifs to be assessed, the identification of more LE scaffolds for optimization and highlighted binding affinity hotspots. Structure-guided addition of a metal-binding pharmacophore onto LE retrofragment scaffolds produced low nanomolar (KD = 15 nM) CYP121 ligands. Elaboration of these compounds to target binding hotspots in the distal active site afforded compounds with excellent selectivity against human drug-metabolizing P450s. Analysis of the factors governing ligand potency and selectivity using X-ray crystallography, UV-vis spectroscopy, and native mass spectrometry provides insight for subsequent drug development.
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Proteínas Bacterianas/antagonistas & inhibidores , Sistema Enzimático del Citocromo P-450/química , Diseño de Fármacos , Inhibidores Enzimáticos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis/tratamiento farmacológico , Sitios de Unión , Cristalografía por Rayos X , Inhibidores Enzimáticos/química , Humanos , Ligandos , Mycobacterium tuberculosis/enzimología , Unión Proteica , Estructura Terciaria de Proteína , Tuberculosis/microbiologíaRESUMEN
UNLABELLED: PROBLEM/BACKGROUND: Pain management is a major worldwide health problem. It manifests itself in a variety of forms involving in turn a multiplicity of responses and therapeutic strategies. Following from this, the training of health personnel must deal with this situation and must not only offer technical assistance, but must also deal with the psychological and social aspects of the problem. In recent years various guidelines and protocols have become popular for pain management. The aim of this paper is to present a literature review of the major international databases. Type of research: Systematic review. OBJECTIVE: To identify relevant studies in the literature on pain management and identify the guidelines recognized by the scientific community. MATERIALS AND METHODS: A literature search was conducted using the keywords "pain management" and "nurse" published since 2000 in English and Italian in the following databases: PubMed, CINAHL, Med Line. Excluding items which did not meet the inclusion criteria, 49 articles were included in the review. RESULTS: Despite a growing availability of evidence-based guidelines, drugs for pain control and the enactment of legislation to promote the use of opioid analgesics in pain therapy, a substantial proportion of the European population continues to have pain. Estimates of the prevalence of pain symptoms in the literature show that between 40% and 63% of hospitalized patients reported pain, peaking at 82.3% in cancer patients in advanced stages of the disease or terminally ill (in hospital or at home). Several studies published in recent years have agreed on a definition of some key points in the management of pain. Studies agree that pain should be recognized as the 5th vital sign, hence the need for validated scales whether single or multi-dimensional, quantitative or qualitative. The approach to the management of pain must be multi-professional, and the use of pharmacology must be in accordance with the WHO three-step approach. Several studies have demonstrated that communication and training of operators, associated with accurate information to patients, are effective elements to improve health care delivered to patients. These studies have led to the publication of guidelines by various scientific societies, indicating timely strategies for effective pain management both in hospital and in the territory. A possible development of this research could be to conduct a retrospective study in accordance with the AUDIT methodology so that we can check the implementation of guidelines and propose corrective actions to meet the defined standards.
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Bases de Datos como Asunto , Manejo del Dolor , HumanosRESUMEN
During an anthrax outbreak at the Pollino National Park (Basilicata, Italy) in 2004, diseased cattle were buried and from these anthrax-foci Bacillus anthracis endospores still diffuse to the surface resulting in local accumulations. Recent data suggest that B. anthracis multiplies in soil outside the animal-host body. This notion is supported by the frequent isolation of B. anthracis from soil lacking one or both virulence plasmids. Such strains represent an evolutionary dead end, as they are likely no longer able to successfully infect new hosts. This loss of virulence plasmids is explained most simply by postulating a soil-borne life cycle of the pathogen. To test this hypothesis we investigated possible microevolution at two natural anthrax foci from the 2004 outbreak. If valid, then genotypes of strains isolated from near the surface at these foci should be on a different evolutionary trajectory from those below residing in deeper-laying horizons close to the carcass. Thus, the genetic diversity of B. anthracis isolates was compared conducting Progressive Hierarchical Resolving Assays using Nucleic Acids (PHRANA) and next generation Whole Genome Sequencing (WGS). PHRANA was not discriminatory enough to resolve the fine genetic relationships between the isolates. Conversely, WGS of nine isolates from near-surface and nine from near-carcass revealed five isolate specific SNPs, four of which were found only in different near-surface isolates. In support of our hypothesis, one surface-isolate lacked plasmid pXO1 and also harbored one of the unique SNPs. Taken together, our results suggest a limited soil-borne life cycle of B. anthracis.
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Carbunco/microbiología , Bacillus anthracis/genética , Evolución Molecular , Estadios del Ciclo de Vida , Microbiología del Suelo , Animales , Carbunco/veterinaria , Bacillus anthracis/crecimiento & desarrollo , Bacillus anthracis/aislamiento & purificación , Bacillus anthracis/patogenicidad , Bovinos , Brotes de Enfermedades , Genoma Microbiano , Polimorfismo de Nucleótido SimpleRESUMEN
To combat the emergence of drug-resistant strains of Mycobacterium tuberculosis, new antitubercular agents and novel drug targets are needed. Phenotypic screening of a library of 594 hit compounds uncovered two leads that were active against M. tuberculosis in its replicating, non-replicating, and intracellular states: compounds 7947882 (5-methyl-N-(4-nitrophenyl)thiophene-2-carboxamide) and 7904688 (3-phenyl-N-[(4-piperidin-1-ylphenyl)carbamothioyl]propanamide). Mutants resistant to both compounds harbored mutations in ethA (rv3854c), the gene encoding the monooxygenase EthA, and/or in pyrG (rv1699) coding for the CTP synthetase, PyrG. Biochemical investigations demonstrated that EthA is responsible for the activation of the compounds, and by mass spectrometry we identified the active metabolite of 7947882, which directly inhibits PyrG activity. Metabolomic studies revealed that pharmacological inhibition of PyrG strongly perturbs DNA and RNA biosynthesis, and other metabolic processes requiring nucleotides. Finally, the crystal structure of PyrG was solved, paving the way for rational drug design with this newly validated drug target.
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Antituberculosos/farmacología , Ligasas de Carbono-Nitrógeno/antagonistas & inhibidores , Mycobacterium tuberculosis/efectos de los fármacos , Oxidorreductasas/metabolismo , Tiofenos/farmacología , Activación Metabólica , Animales , Antituberculosos/química , Proteínas Bacterianas/metabolismo , Ligasas de Carbono-Nitrógeno/química , Ligasas de Carbono-Nitrógeno/metabolismo , Diseño de Fármacos , Evaluación Preclínica de Medicamentos/métodos , Células Hep G2 , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Mycobacterium tuberculosis/enzimología , Mycobacterium tuberculosis/metabolismo , Oxidorreductasas/química , Conformación Proteica , Tiofenos/químicaRESUMEN
Despite the resistance developed by the Mycobacterium tuberculosis (MTb) strains, isoniazid (INH) has been recognized as one of the best drug for treatment of Tuberculosis (Tb). The coordination of INH to ruthenium metal centers was investigated as a strategy to enhance the activity of this drug against the sensitive and resistant strains of MTb. The complexes trans-[Ru(NH3)4(L)(INH)](2+) (L=SO2 or NH3) were isolated and their chemical and antituberculosis properties studied. The minimal inhibitory concentration (MIC) data show that [Ru(NH3)5(INH)](2+) was active in both resistant and sensitive strains, whereas free INH (non-coordinated) showed to be active only against the sensitive strain. The coordination of INH to the metal center in both [Ru(NH3)5(INH)](2+) and trans-[Ru(NH3)4(SO2)(INH)](2+) complexes led to a shift in the INH oxidation potential to less positive values compared to free INH. Despite, the ease of oxidation of INH did not lead to an increase in the in vitro INH activity against MTb, it might have provided sensitivity toward resistant strains. Furthermore, ruthenium complexes with chemical structures analogous to those described above were synthesized using the oxidation products of INH as ligands (namely, isonicotinic acid and isonicotinamide). These last compounds were not active against any strains of MTb. Moreover, according to DFT calculations the formation of the acyl radical, a proposed intermediate in the INH oxidation, is favored in the [Ru(NH3)5(INH)](2+) complex by 50.7kcalmol(-1) with respect to the free INH. This result suggests that the stabilization of the acyl radical promoted by the metal center would be a more important feature than the oxidation potential of the INH for the antituberculosis activity against resistant strains.
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Antituberculosos/farmacología , Isoniazida/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Rutenio/farmacología , Animales , Antituberculosos/uso terapéutico , Chlorocebus aethiops , Isoniazida/uso terapéutico , Pruebas de Sensibilidad Microbiana/métodos , Mycobacterium tuberculosis/fisiología , Rutenio/uso terapéutico , Tuberculosis/tratamiento farmacológico , Células VeroRESUMEN
In the search for new therapeutic tools against tuberculosis and to further address the therapeutic potential of pyridine-2-thiol 1-oxide (Hmpo) metal complexes, two new octahedral [M(III)(mpo)3] complexes, with M = Ga or Bi, were synthesized and characterized in the solid state and in solution. Attempts to crystallize [Ga(III)(mpo)3] in CH2Cl2 led to single crystals of the reaction product [GaCl(mpo)2], where the gallium(III) ion is in a square basis pyramidal environment, trans-coordinated at the basis to two pyridine-2-thiolato 1-oxide anions acting as bidentate ligands through their oxygen and sulfur atoms. The biological activity of the new [M(III)(mpo)3] complexes together with that of the previously reported Fe(III) analogous compound and the pyridine-2-thiol 1-oxide sodium salt (Na mpo) was evaluated on Mycobacterium tuberculosis. The compounds showed excellent activity, both in the standard strain H37Rv ATCC 27294 (pan-susceptible) and in five clinical isolates that are resistant to the standard first-line anti-tuberculosis drugs isoniazid and rifampicin. These pyridine-2-thiol 1-oxide derivatives are promising compounds for the treatment of resistant tuberculosis.
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Antibacterianos/química , Antibacterianos/farmacología , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Animales , Antibacterianos/toxicidad , Bismuto/química , Chlorocebus aethiops , Complejos de Coordinación/toxicidad , Cristalografía por Rayos X , Galio/química , Hierro/química , Pruebas de Sensibilidad Microbiana , Células VeroRESUMEN
We assessed the performance of REMA in comparison with BACTEC MGIT 960 in the susceptibility testing of 80 Mycobacterium tuberculosis clinical isolates from Clemente Ferreira Institute against four drugs. REMA proved to be a rapid and accurate method, providing excellent correlation with BACTEC MGIT 960, with the exception of results for the ethambutol drug.
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BACKGROUND: In this work are reported the results of a qualitative analytical method capable of detecting Bacillus anthracis spores when they are present in very low concentration in the soil. The Ground Anthrax Bacillus Refined Isolation (GABRI) method, assessed in our laboratory, was compared with the classic method. The comparison involved artificially anthrax-contaminated soil samples (500 spores/7.5 grams soil) and naturally contaminated soil samples collected in Bangladesh during a field investigation. RESULTS: The results indicated that, in contrast to the classic method, the GABRI method was able to detect B.anthracis in all contaminated samples. The GABRI method produces a more sensitive measure of anthrax spore presence significantly different from the standard method. In particular, the latter is more sensitive to the presence of normal soil contaminants. CONCLUSION: The main feature of the GABRI method is its ability to strongly reduce the presence of the environmental contaminants, which being much more numerous than B. anthracis tend to inhibit their germination and growth making it extremely difficult to visualize any colonies. The reduction of the microbial environment also allows one to be able to culture and test a larger quantity of potentially contaminated soil and to isolate B. anthracis when the spores are present in very low concentrations in the soil.
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Bacillus anthracis/aislamiento & purificación , Técnicas Bacteriológicas/métodos , Microbiología Ambiental , Bangladesh , Sensibilidad y Especificidad , Esporas Bacterianas/aislamiento & purificaciónRESUMEN
We assessed the performance of REMA in comparison with BACTEC MGIT 960 in the susceptibility testing of 80 Mycobacterium tuberculosis clinical isolates from Clemente Ferreira Institute against four drugs. REMA proved to be a rapid and accurate method, providing excellent correlation with BACTEC MGIT 960, with the exception of results for the ethambutol drug.