The drug efflux protein, P-glycoprotein, additionally protects drug-resistant tumor cells from multiple forms of caspase-dependent apoptosis

Multidrug resistance mediated by the drug efflux protein, P-glycoprotein (P-gp), is one mechanism that tumor cells use to escape death induced by chemotherapeutic agents. However, the mechanism by which P-gp confers resistance to a large variety of structurally diverse molecules has remained elusive. In this study, classical multidrug resistant human CEM and K562 tumor cell lines expressing high levels of P-gp were less sensitive to multiple forms of caspase-dependent cell death, including that mediated by cytotoxic drugs and ligation of Fas. The DNA fragmentation and membrane damage inflicted by these stimuli were defined as caspase dependent by various soluble peptide fluoromethylketone caspase inhibitors. Inhibition of P-gp function by the anti-P-gp mAb MRK-16 or verapamil could reverse resistance to these forms of cell death. Inhibition of P-gp function also enhanced drug or Fas-mediated activation of caspase-3 in drug-resistant CEM cells. By contrast, caspase-independent cell death events in the same cells, including those mediated by pore-forming proteins or intact NK cells, were not affected by P-gp expression. These observations suggest that, in addition to effluxing drugs, P-gp may play a specific role in regulating some caspase-dependent apoptotic pathways.

A multidrug resistance transporter from human MCF-7 breast cancer cells

MCF-7/AdrVp is a multidrug-resistant human breast cancer subline that displays an ATP-dependent reduction in the intracellular accumulation of anthracycline anticancer drugs in the absence of overexpression of known multidrug resistance transporters such as P glycoprotein or the multidrug resistance protein. RNA fingerprinting led to the identification of a 2.4-kb mRNA that is overexpressed in MCF-7/AdrVp cells relative to parental MCF-7 cells. The mRNA encodes a 663-aa member of the ATP-binding cassette superfamily of transporters that we term breast cancer resistance protein (BCRP). Enforced expression of the full-length BCRP cDNA in MCF-7 breast cancer cells confers resistance to mitoxantrone, doxorubicin, and daunorubicin, reduces daunorubicin accumulation and retention, and causes an ATP-dependent enhancement of the efflux of rhodamine 123 in the cloned transfected cells. BCRP is a xenobiotic transporter that appears to play a major role in the multidrug resistance phenotype of MCF-7/AdrVp human breast cancer cells.

Frequência de resistência a múltiplos fármacos em pseudomonas aeroginosa

A multirresistência bacteriana tem crescido significativamente nos últimos anos. Entre os gram negativos a P. aeruginosa demonstra facilidade de desenvolvimento de resistência aos antibióticos. O objetivo deste estudo foi determinar a frequência de resistência a múltiplos fármacos em isolados de Pseudomonas aeruginosa e detectar cepas multirresistentes em um hospital público de Maceió/AL. De forma retrospectiva, descritiva e transversal, entre janeiro de 2012 a dezembro de 2013, iniciou-se uma ampla análise documental dos registros de atendimento no setor de Microbiologia do Hospital Universitário Professor Alberto Antunes (HUPAA/UFAL) para avaliar o material obtido de pacientes que apresentaram cultura positiva para P. aeruginosa. Vários espécimes clínicos foram obtidos e as cepas identificadas fenotipicamente pelo método automatizado Vitek®, bem como as análises do perfil de susceptibilidade aos antimicrobianos, seguindo os critérios adotados pelo National Committee for Clinical and Laboratory Standards (NCCLS). Foram obtidas 78 culturas com isolados positivos para P. aeruginosa, sendo a maioria procedente de pacientes da UTI geral (47,4%), seguida da Clínica cirúrgica (16,7%). Entre as amostras clínicas analisadas, a secreção traqueal foi a de maior incidência com 25,6%, seguida de secreção de ferida (20,5%) e escarro (18%). O composto mais ativo contra a P. aeruginosa foi a Colistina (100,0%). Detectou-se elevada multirresistência de P. aeruginosa aos betalactâmicos, cefalosporinas e carbapenêmicos. Baseando-se nos dados apresentados, torna-se evidente a necessidade de um monitoramento rotineiro do perfil de sensibilidade desta bactéria em ambiente hospitalar, sendo de extrema utilidade para a escolha adequada na terapêutica empírica, proporcionando conhecimento prévio dos antimicrobianos que apresentam boa eficácia diante deste patógeno, favorecendo o uso racional de antimicrobianos. PALAVRAS-CHAVE: Multirresistência; Pseudomonas aeruginosa;Sensibilidade; Antimicrobianos.

Multiplex PCR for Assessment of Tetracycline Resistance (tet) Genes in Antibiotic-Resistant Soil Bacteria and the Ecological Implications

Antibiotics are becoming increasingly prevalent in bacterial communities due to clinical and agricultural misuse and overuse in their environment. As exposure increases, so does the incidence of microbial resistance. Such is the case with bacterial resistance to tetracyclines, a phenotype often acquired through the horizontal gene transfer of tet genes between bacteria. The objective of this project was to analyze the bacterial diversity of tet resistance genes in soil from Miami-Dade County. Bacterial isolates were Gram-stained and the Kirby-Bauer antibiotic disk diffusion test was performed to determine each bacterium’s degree of resistance. The 16S rRNA gene from antibiotic-resistant isolates was amplified by PCR and sequenced to identify the isolates. All isolates’ tet genes were amplified by multiplex PCR, sequenced, and compared. Among eight isolates, three distinct species were positively identified based on their 16S rRNA sequences and four distinct tet genes were identified, though all tested susceptible to tetracycline via the Kirby-Bauer test. This project clarifies some aspects of the ecology of antibiotic resistance genes, their natural ecological function and the potential for the expansion of intrinsic multi-antibiotic resistance into new ecosystems and/or hosts.

Infecções por enterobacteriaceae resistente aos carbapenêmicos em hospital de ensino: epidemiologia e caracterização molecular

Introduction: The production of KPC (Klebsiella pneumoniae carbapenemase) has become an important mechanism of carbapenem-resistance among Enterobacteriaceae strains. In Brazil, KPC is already widespread and its incidence has increased significantly, reducing treatment options. The “perfect storm” combination of the absence of new drug developmentand the emergence of multidrug-resistant strains resulted in the need for the use of older drugs, with greater toxicity, such as polymyxins. Aims: To determine the occurrence of carbapenemase-producing strains in carbapenem-resistant Enterobacteriaceae isolated from patients with nosocomial infection/colonization during September/2014 to August/2015, to determine the risk factors associated with 30-day- mortality and the impact of inappropriate therapy. Materials and Methods: We performed a case control study to assess the risk factors (comorbidities, invasive procedures and inappropriate antimicrobial therapy) associated with 30-day-mortality, considering the first episode of infection in 111 patients. The resistance genes blaKPC, blaIMP, blaVIM and blaNDM-1 were detected by polymerase chain reaction technique. Molecular typing of the strains involved in the outbreak was performed by pulsed field gel electrophoresis technique. The polymyxin resistance was confirmed by the microdilution broth method. Results: 188 episodes of carbapenem-resistant Enterobacteriaceae infections/colonizations were detected; of these, 122 strains were recovered from the hospital laboratory. The presence of blaKPC gene were confirmed in the majority (74.59%) of these isolates. It was not found the presence of blaIMP , blaVIM and blaNDM-1 genes. K. pneumoniae was the most frequent microorganism (77,13%), primarily responsible for urinary tract infections (21,38%) and infections from patients of the Intensive Care Unit (ICU) (61,38%). Multivariate statistical analysis showed as predictors independently associated with mortality: dialysis and bloodstream infection. The Kaplan-Meier curve showed a lower probability of survival in the group of patients receiving antibiotic therapy inappropriately. Antimicrobial use in adult ICU varied during the study period, but positive correlation between increased incidence of strains and the consumption was not observed. In May and July 2015, the occurrence rates of carbapenem-resistant Enterobacteriaceae KPC-producing per 1000 patient-days were higher than the control limit established, confirming two outbreaks, the first caused by colistin-susceptible KPC-producing K. pneumoniae isolates, with a polyclonal profile and the second by a dominant clone of colistin-resistant (≥ 32 μg/mL) KPC-producing K. pneumoniae. The cross transmission between patients became clear by the temporal and spatial relationships observed in the second outbreak, since some patients occupied the same bed, showing problems in hand hygiene adherence among healthcare workers and inadequate terminal disinfection of environment. The outbreak was contained when the ICU was closed to new admissions. Conclusions: The study showed an endemicity of K. pneumoniae KPC-producing in adult ICU, progressing to an epidemic monoclonal expansion, resulted by a very high antibiotic consumption of carbapenems and polymyxins and facilitated by failures in control measures the unit.

Impacto na epidemiologia da sepse tardia após a mudança do protocolo de antimicrobianos em uma UTIN de um serviço universitário

Advances in neonatology resulted in reducing the mortality rate and the consequent increase in survival of newborn pre terms (PTN). On the other hand, there was also a considerable increase in the risk of developing health care-related infection (HAI) in its most invasive, especially for bloodstream. This situation is worrying, and prevent the occurrence of it is a challenge and becomes one of the priorities in the Neonatal Intensive Care Unit (NICU). Sepsis is the main cause of death in critical neonates and affects more than one million newborns each year, representing 40% of all deaths in neonates. The incidence of late sepsis can reach 50% in NICUs. Currently the major responsible for the occurrence of sepsis in developed countries is the coagulase negative Staphylococcus (CoNS), followed by S. aureus. The cases of HAIs caused by resistant isolates for major classes of antimicrobial agents have been increasingly frequent in the NICU. Therefore, vancomycin has to be prescribed more frequently, and, today, the first option in the treatment of bloodstream infections by resistant Staphylococcus. The objectives of this study were to assess the impact on late sepsis in epidemiology III NICU after the change of the use of antimicrobials protocol; check the frequency of multiresistant microorganisms; assess the number of neonates who came to death. This study was conducted in NICU Level III HC-UFU. three study groups were formed based on the use of the proposed late sepsis treatment protocol, with 216 belonging to the period A, 207 B and 209 to the C. The work was divided into three stages: Period A: data collected from neonates admitted to the unit between September 2010 to August 2011. was using treatment of late sepsis: with oxacillin and gentamicin, oxacillin and amikacin, oxacillin and cefotaxime. Period B: data were collected from March 2012 to February 2013. Data collection was started six months after protocol change. Due to the higher prevalence of CoNS, the initial protocol was changed to vancomycin and cefotaxime. Period C: data were collected from newborns inteerne in the unit from September 2013 to August 2014. Data collection was started six months after the protocol change, which occurred in March 2013. From the 632 neonates included in this study, 511 (80,8%) came from the gynecology and obstetrics department of the HC-UFU. The mean gestational age was 33 weeks and the prevailing sex was male (55,7%). Seventy-nine percent of the studied neonates were hospitalized at the NICU HC-UFU III because of complications related to the respiratory system. Suspicion of sepsis took to hospitalization in the unit of 1,9% of newborns. In general, the infection rate was 34,5%, and the most frequent infectious sepsis syndrome 81,2%. There was a tendency to reduce the number of neonates who died between periods A 11 and C (p = 0,053). From the 176 cases of late sepsis, 73 were clinical sepsis and 103 had laboratory confirmation, with greater representation of Gram positive bacteria, which corresponded to 67.2% of the isolates and CoNS the most frequent micro-organism (91,5%). There was a statistically significant difference in the reduction of isolation of Gram positive microorganisms between periods A and C (p = 0,0365) as well as in reducing multidrug-resistant CoNS (A and B period p = 0,0462 and A and C period, p = 0,158). This study concluded that: the CoNS was the main microorganism responsible for the occurrence of late sepsis in neonates in the NICU of HC-UFU; the main risk factors for the occurrence of late sepsis were: birth weight <1500 g, use of PICC and CUV, need for mechanical ventilation and parenteral nutrition, SNAPPE> 24 and length of stay more than seven days; the new empirical treatment protocol late sepsis, based on the use of vancomycin associated cefepime, it was effective, since promoted a reduction in insulation CoNS blood cultures between the pre and post implementation of the Protocol (A and C, respectively); just as there was a reduction in the number of newborns who evolved to death between periods A and C.

Antimicrobial susceptibility of Pseudomonas aeruginosa isolated from cystic fibrosis patients through Northern Europe

Pseudomonas aeruginosa is a major cause of morbidity and mortality in cystic fibrosis patients. This study compares the antimicrobial susceptibility of 153 P. aeruginosa isolates from the United Kingdom (UK) (n=58), Belgium (n=44), and Germany (n=51) collected from 120 patients during routine visits over the 2006-2012 period. MICs were measured by broth microdilution. Genes encoding extended spectrum β-lactamases (ESBL), metallo-β-lactamases and carbapenemases were detected by PCR. Pulsed Field Gel Electrophoresis and Multi-Locus Sequence Typing were performed on isolates resistant to ≥ 3 antibiotic classes among penicillins/cephalosporins, carbapenems, fluoroquinolones, aminoglycosides, polymyxins. Based on EUCAST/CLSI breakpoints, susceptibility was ≤ 30%/≤ 40% (penicillins, ceftazidime, amikacin, ciprofloxacin), 44-48%/48-63% (carbapenems), 72%/72% (tobramycin), and 92%/78% (colistin) independently of patient's age. Sixty percent of strains were multidrug resistant (MDR; European Centre for Disease prevention and Control criteria). Genes encoding ESBL (most prevalent BEL, PER, GES, VEB, CTX-M, TEM, SHV, and OXA), metallo β-lactamases (VIM, IMP, NDM), or carbapenemases (OXA-48, KPC) were not detected. The Liverpool Epidemic Strain (LES) was prevalent in UK isolates only (75% of MDR isolates). Four MDR ST958 isolates were found spread over the three countries. The other MDR clones were evidenced in ≤ 3 isolates and localized in a single country. A new sequence type (ST2254) was discovered in one MDR isolate in Germany. Clonal and non-clonal isolates with different susceptibility profiles were found in 21 patients. Thus, resistance and MDR are highly prevalent in routine isolates from 3 countries, with carbapenem (meropenem), tobramycin and colistin remaining the most active drugs.

The temperate Burkholderia phage AP3 of the Peduovirinae shows efficient antimicrobial activity against B. cenocepacia of the IIIA lineage

Burkholderia phage AP3 (vB_BceM_AP3) is a temperate virus of the Myoviridae and the Peduovirinae subfamily (P2likevirus genus). This phage specifically infects multidrug-resistant clinical Burkholderia cenocepacia lineage IIIA strains commonly isolated from cystic fibrosis patients. AP3 exhibits high pairwise nucleotide identity (61.7%) to Burkholderia phage KS5, specific to the same B. cenocepacia host, and has 46.7% - 49.5% identity to phages infecting other species of Burkholderia. The lysis cassette of these related phages has a similar organization (putative antiholin, putative holin, endolysin and spanins) and shows 29-98% homology between specific lysis genes, in contrast to Enterobacteria phage P2, the hallmark phage of this genus. The AP3 and KS5 lysis genes have conserved locations and high amino acid sequence similarity. The AP3 bacteriophage particles remain infective up to 5 h at pH 4-10 and are stable at 60°C for 30 min, but are sensitive to chloroform, with no remaining infective particles after 24 h of treatment. AP3 lysogeny can occur by stable genomic integration and by pseudo-lysogeny. The lysogenic bacterial mutants did not exhibit any significant changes in virulence compared to wild-type host strain when tested in the Galleria mellonella moth wax model. Moreover, AP3 treatment of larvae infected with B. cenocepacia revealed a significant increase (P < 0.0001) in larvae survival in comparison to AP3-untreated infected larvae. AP3 showed robust lytic activity, as evidenced by its broad host range, the absence of increased virulence in lysogenic isolates, the lack of bacterial gene disruption conditioned by bacterial tRNA downstream integration site, and the absence of detected toxin sequences. These data suggest the AP3 phage is a promising potent agent against bacteria belonging to most common B. cenocepacia IIIA lineage strains.

Daunorubicin and gambogic acid co-loaded cysteamine-CdTe quantum dots minimizing the multidrug resistance of lymphoma in vitro and in vivo

To minimize the side effects and the multidrug resistance (MDR) arising from daunorubicin (DNR) treatment of malignant lymphoma, a chemotherapy formulation of cysteamine-modified cadmium tellurium (Cys-CdTe) quantum dots coloaded with DNR and gambogic acid (GA) nanoparticles (DNR-GA-Cys-CdTe NPs) was developed. The physical property, drug-loading efficiency and drug release behavior of these DNR-GA-Cys-CdTe NPs were evaluated, and their cytotoxicity was explored by 3-[4,5-dimethylthiazol-2-y1]-2,5-diphenyltetrazolium bromide assay. These DNR-GA-Cys-CdTe NPs possessed a pH-responsive behavior, and displayed a dose-dependent antiproliferative activity on multidrug-resistant lymphoma Raji/DNR cells. The accumulation of DNR inside the cells, revealed by flow cytometry assay, and the down-regulated expression of P-glycoprotein inside the Raji/DNR cells measured by Western blotting assay indicated that these DNR-GA-Cys-CdTe NPs could minimize the MDR of Raji/DNR cells. This multidrug delivery system would be a promising strategy for minimizing MDR against the lymphoma.

The biofilm inhibitor Carolacton inhibits planktonic growth of virulent pneumococci via a conserved target

New antibacterial compounds, preferentially exploiting novel cellular targets, are urgently needed to fight the increasing resistance of pathogens against conventional antibiotics. Here we demonstrate that Carolacton, a myxobacterial secondary metabolite previously shown to damage Streptococcus mutans biofilms, inhibits planktonic growth of Streptococcus pneumoniae TIGR4 and multidrug-resistant clinical isolates of serotype 19A at nanomolar concentrations. A Carolacton diastereomer is inactive in both streptococci, indicating a highly specific interaction with a conserved cellular target. S. mutans requires the eukaryotic-like serine/threonine protein kinase PknB and the cysteine metabolism regulator CysR for susceptibility to Carolacton, whereas their homologues are not needed in S. pneumoniae, suggesting a specific function for S. mutans biofilms only. A bactericidal effect of Carolacton was observed for S. pneumoniae TIGR4, with a reduction of cell numbers by 3 log units. The clinical pneumonia isolate Sp49 showed immediate growth arrest and cell lysis, suggesting a bacteriolytic effect of Carolacton. Carolacton treatment caused a reduction in membrane potential, but not membrane integrity, and transcriptome analysis revealed compensatory reactions of the cell. Our data show that Carolacton might have potential for treating pneumococcal infections.

Avaliação do potencial de formigas (Hymenoptera: formicidae) como vetores mecânicos de bactérias do gêneroSstaphylococcus no ambiente hospitalar.

In a hospital environment, these bacteria can be spread by insects such as ants, which are characterized by high adaptability to the urban environment. Staphylococcus is a leading cause of hospital infection. In Europe, Latin America, USA and Canada, the group of coagulase negative staphylococci (CoNS) is the second leading cause of these infections, according to SENTRY (antimicrobial surveillance program- EUA). In this study, we investigated the potential of ants (Hymenoptera: Formicidae) as vehicle mechanics of Staphylococcus bacteria in a public hospital, in Natal-RN. The ants were collected, day and night, from June 2007 to may 2008, in the following sectors: hospitals, laundry, kitchen, blood bank. The ants were identified according to the identification key of Bolton, 1997. For the analysis of staphylococci, the ants were incubated in broth Tryptic Soy Broth (TSB) for 24 hours at 35 º C and then incubated on Mannitol Salt Agar. The typical colonies of staphylococci incubated for 24 hours at 35 ° C in Tryptic Soy Agar for the characterization tests (Gram stain, catalase, susceptibility to bacitracin and free coagulase). The identification of CoNS was performed through biochemical tests: susceptibility to novobiocin, growth under anaerobic conditions, presence of urease, the ornithine decarboxylation and acid production from the sugars mannose, maltose, trehalose, mannitol and xylose. The antimicrobial susceptibility examined by disk-diffusion technique. The technique of Polymerase Chain Reaction was used to confirm the presence of mecA gene and the ability to produce biofilm was verified by testing in vitro using polystyrene inert surface, in samples of resistant staphylococci. Among 440 ants, 85 (19.1%) were carrying coagulase-negative staphylococci (CoNS) of the species Staphylococcus saprophyticus (17), Staphylococcus epidermidis (15), Staphylococcus xylosus (13), Staphylococcus hominis hominis (10), Staphylococcus lugdunensis (10), Staphylococcus warneri (6), Staphylococcus cohnii urealyticum (5), Staphylococcus haemolyticus (3), Staphylococcus simulans (3), Staphylococcus cohnii cohnii (2), and Staphylococcus capitis (1). No Staphylococcus aureus was found. Among the isolates, 30.58% showed resistance to erythromycin. Two samples of CoNS (2.35%), obtained from the ant Tapinoma melanocephalum collected in the post-surgical female ward, S. Hominis hominis and S. lugdunensis harbored the mecA gene and were resistant to multiple antibiotics, and the specie S. hominis hominis even showed to be a biofilm producer. This study proves that ants act as carriers of multidrug-resistant coagulase-negative Staphylococci and biofilm producers and points to the risk of the spreading of pathogenic microorganisms by this insect in the hospital environment

Klebsiella pneumoniae sequence type 11 from companion animals bearing ArmA methyltransferase, DHA-1 β-lactamase, and QnrB4

Seven Klebsiella pneumoniae isolates from dogs and cats in Spain were found to be highly resistant to aminoglycosides, and ArmA methyltransferase was responsible for this phenotype. All isolates were typed by multilocus sequence typing (MLST) as ST11, a human epidemic clone reported worldwide and associated with, among others, OXA-48 and NDM carbapenemases. In the seven strains, armA was borne by an IncR plasmid, pB1025, of 50 kb. The isolates were found to coproduce DHA-1 and SHV-11 β-lactamases, as well as the QnrB4 resistance determinant. This first report of the ArmA methyltransferase in pets illustrates their importance as a reservoir for human multidrug-resistant K. pneumoniae.

Evaluación del desempeño de pruebas diagnósticas de tuberculosis en pacientes VIH positivo en dos hospitales públicos de Bogotá

La tuberculosis TB es una de las principales causas de muerte en el mundo en individuos con infección por VIH. En Colombia esta coinfección soporta una carga importante en la población general convirtiéndose en un problema de salud pública. En estos pacientes las pruebas diagnósticas tienen sensibilidad inferior y la enfermedad evoluciona con mayor frecuencia hacia formas diseminadas y rápidamente progresivas y su diagnóstico oportuno representa un reto en Salud. El objetivo de este proyecto es evaluar el desempeño de las pruebas diagnósticas convencionales y moleculares, para la detección de TB latente y activa pacientes con VIH, en dos hospitales públicos de Bogotá. Para TB latente se evaluó la concordancia entre las pruebas QuantiFERON-TB (QTF) y Tuberculina (PPD), sugiriendo superioridad del QTF sobre la PPD. Se evaluaron tres pruebas diagnósticas por su sensibilidad y especificidad, baciloscopia (BK), GenoType®MTBDR plus (Genotype) y PCR IS6110 teniendo como estándar de oro el cultivo. Los resultados de sensibilidad (S) y especificidad (E) de cada prueba con una prevalencia del 19,4 % de TB pulmonar y extrapulmonar en los pacientes que participaron del estudio fue: BK S: 64% E: 99,1%; Genotype S: 77,8% E: 94,5%; PCRIS6110 S: 73% E: 95,5%, de la misma forma se determinaron los valores predictivos positivos y negativos (VPP y VPN) BK: 88,9% y 94,8%, Genotype S: 77,8% E: 94,5%; PCRIS6110 S: 90% y 95,7%. Se concluyó bajo análisis de curva ROC que las pruebas muestran un rendimiento diagnóstico similar por separado en el diagnóstico de TB en pacientes con VIH, aumentando su rendimiento diagnostico cuando se combinan

Perfil epidemiológico y análisis de la formulación antibiótica en pacientes con infección urinaria nosocomial en la Fundación Cardioinfantil en el año 2014

Introducción: La IVU es muy frecuenten en la (FCI - IC), Alrededor el 60% de los pacientes con diagnóstico de IVU nosocomial corresponden a gérmenes resistente, Desde el año 2010 el CLSI disminuyó los puntos de corte de sensibilidad en las enterobacteriaceae y removió la necesidad de tamizaje y confirmación de (BLEE), en el presente trabajo se pretende determinar el perfil epidemiológico de la formulación antibiótica en pacientes con IVU nosocomial. Diseño: Se realizó un estudio observacional analítico de corte transversal. Métodos: Se realizó un análisis univariado, bivariado y multivariado. El análisis bivariado y multivariado se realizó para determinar la medida de asociación teniendo en cuenta la formulación de Carbapenemico la variable dependiente, evaluándose mediante chi cuadrado. Resultados: Se revisaron 131 urocultivos, se incluyeron 116. Los aislamientos microbiológicos más frecuentemente encontrados fueron E. Coli y K. Pneumoniae, el 43.4% de los aislamientos, presentaron expresión de BLEE, 90% de los aislamientos fueron sensibles a Cefepime. La mayoría de los modelos obtenidos mostraron una fuerte asociación entre el reporte de BLEE en antibiograma con la formulación de carbapenémicos como terapia final OR 33,12 IC 95% (2,90 – 337,4). Conclusión: La epidemiologia de la IVU nosocomial en la FCI-IC no difiere de las referencias internacionales, no hay adherencia a las guías de manejo intrahospitalario y el reporte de la palabra BLEE en el antibiograma predice la formulación de antibiótico carbapenémico por el médico que lee el urocultivo

Photodynamic Antimicrobial Effects Of Bis-indole Alkaloid Indigo From Indigofera Truxillensis Kunth (leguminosae).

Multidrug-resistant microbial infections represent an exponentially growing problem affecting communities worldwide. Photodynamic therapy is a promising treatment based on the combination of light, oxygen, and a photosensitizer that leads to reactive oxygen species production, such as superoxide (type I mechanism) and singlet oxygen (type II mechanism) that cause massive oxidative damage and consequently the host cell death. Indigofera genus has gained considerable interest due its mutagenic, cytotoxic, and genotoxic activity. Therefore, this study was undertaken to investigate the effect of crude extracts, alkaloidal fraction, and isolated substance derived from Indigofera truxillensis in photodynamic antimicrobial chemotherapy on the viability of bacteria and yeast and evaluation of mechanisms involved. Our results showed that all samples resulted in microbial photoactivation in subinhibitory concentration, with indigo alkaloid presenting a predominant photodynamic action through type I mechanism. The use of CaCl2 and MgCl2 as cell permeabilizing additives also increased gram-negative bacteria susceptibility to indigo.