Anti-inflammatory effect, antibiotic potentiating activity against multidrug-resistant strains of Escherichia coli and Staphylococcus aureus, and evaluation of antibiotic resistance mechanisms by the ibuprofen derivative methyl 2-(-4-isobutylphenyl)propanoate.

The prevalence of multidrug-resistant (MDR) bacteria and the limited efficacy of current available antibiotics cause every year approximately 700 000 deaths per year. This study aimed to evaluate the anti-inflammatory effect and antibacterial potential of the ibuprofen derivative Methyl 2-(-4-isobutylphenyl)propanoate (MET-IBU). The molecular structure of MET-IBU was confirmed by Nuclear Magnetic Resonance (NMR) and, Attenuated Total Reflectance Fourier Transform Infrared spectroscopy (ATR-FTIR) spectroscopy. Our in vivo study using adult zebrafish model demonstrated that the ibuprofen derivative MET-IBU also possesses anti-inflammatory effect, and in vitro antibacterial activity assays showed that in the association of ampicillin, norfloxacin, and gentamicin with MET-IBU occurred reduction in the minimum inhibitory concentration (MIC) for MDR bacterial strains of Escherichia coli 06 and Staphylococcus aureus 10, indicating a potentiating in the growth inhibition of these pathogenic bacteria. Regarding the strain of Staphylococcus aureus K2068 (overexpressing mepA gene), a potentiation of ethidium bromide was found in the association with MET-IBU, indicating the action of this compound on the efflux pump mechanism present in this strains. This result corroborates the molecular docking study that indicated a high affinity of the MET-IBU with the MepA efflux pump. It was also noticed an antibiotic potentiating activity in the association MET-IBU with norfloxacin against strains of Staphylococcus aureus 1199B (overexpressing norA gene) when compared to the norfloxacin control. This enhanced antibiotic effect of MET-IBU is associated with a second resistance mechanism, which is due to the modification in the topoisomerase enzyme. These results bring attention to the ibuprofen derivative MET-IBU as possible candidate for the development of new options for the treatment of bacterial infections with protective anti-inflammatory action.

Adverse reactions and adherence to capecitabine: A prospective study in patients with gastrointestinal cancer.

INTRODUCTION: Capecitabine is an oral anticancer drug which can cause some adverse reactions and the great challenge for its use is to ensure the medication adherence. The aim of this study was to analyze adverse reactions and adherence to capecitabine in patients with gastrointestinal cancer. METHODS: A prospective study was performed in a tertiary teaching hospital in Brazil. Outpatients undergoing capecitabine treatment for colorectal or gastric cancer were followed for three cycles of treatment. Patient demographic and clinical characteristics data were collected. Adverse reactions were analyzed using Common Terminology Criteria for Adverse Events (CTCAE) v.4. Adherence to capecitabine were evaluated using Morisky-Green and MedTake tests. Statistical analysis was conducted using Chi-square, Fisher's exact and McNemer tests. RESULTS: One hundred and four patients were enrolled in this study, with a mean age was 58.5 ± 10.9 years; 51.0% were men and 51.0% Caucasian. Nausea and diarrhea were the most frequently reported adverse reactions (82.7% and 62.5%, respectively), followed by vomiting (54.8%), fatigue (54.8%), and hand-foot syndrome (53.9%). Nausea and diarrhea were also the most severe adverse reactions. Most patients were adherent to capecitabine in all cycles of treatment using the Morisky-Green test. Adherence increased significantly between cycle 1 and cycle 2 by MedTake test (p < 0.001). Some demographic and clinical characteristics were associated with adverse reactions (e.g., age and nausea, gender and nausea and vomiting) and capecitabine adherence (e.g., marital status and educational level) as well as some adverse reactions were associated with capecitabine adherence (hand-foot syndrome and nausea). CONCLUSIONS: Clinical oncology pharmacists must provide patient information on the correct use of capecitabine, manage adverse reactions, and monitor adherence to treatment. Strategies to prevent non-adherence to capecitabine must be adopted to ensure the success of pharmacotherapy.

Nickel (II) chloride schiff base complex: Synthesis, characterization, toxicity, antibacterial and leishmanicidal activity.

The use of schiff base complex against microbial agentes a has recently received more attention as a strategy to combat infections caused by multidrug-resistant bacteria and leishmania. This study aimed to evaluate the toxicity, antibacterial and leishmanicidal activities of the nickel (II) chloride schiff base complex ([Ni(L2)] against Leishmania amazonensis promastigote, multi-resistant bacterial strains and evaluate to modulate antibiotic activity against multi-resistant bacterial. The schiff base complex was characterized by the techniques of elemental analysis, Fourier transform infrared spectroscopy (FTIR), UV-vis absorption spectroscopy and thermal analysis (TGA/DTG/DSC). The [Ni(L2)] complex presented moderate toxicity in saline artemia (LC50 = 150.8 µg/mL). In leishmanicidal assay, the NiL2 complex showed values of IC50 of (6.079 µg/mL ± 0.05656 at the 24 h), (0.854 µg/mL ± 0.02474, 48 h) and (1.076 µg/mL ± 0.04039, 72 h). In antibacterial assay, the [Ni(L2)] complex presented significant inhibited the bacterial growth of P. aeruginosa (MIC = 256 µg/mL). However, [Ni(L2)] complex did not present clinically relevant minimum inhibitory concentration (MIC ≥1024 µg/mL) against S. aureus and E. coli. The combination of [Ni(L2)] complex and antibacterial drugs resulted in the increased antibiotic activity of gentamicin and amikacin against S. aureus and E.coli multi-resistant strains. Thus, our results showed that [Ni(L2)] complex is a promising molecule for the development of new therapies associated with aminoglycoside antibiotics and in disease control related to resistant bacteria and leishmaniasis.

In vitro and in silico studies of chalcones derived from natural acetophenone inhibitors of NorA and MepA multidrug efflux pumps in Staphylococcus aureus.

Bacterial resistance induced by efflux pumps is a frequent concern in clinical treatments involving multi-resistant bacteria. Staphylococcus aureus is a microorganism responsible for several types of infections and has several strains carrying efflux pumps, among them are the strain 1199B (NorA overexpresser), and the strain K2068 (MepA overexpresser). In this work, four chalcones derived from Croton anisodontus with modifications in the B ring in their structures were tested regarding their ability to inhibit NorA and MepA efflux pumps. The efflux pump inhibition mechanism was tested with the ethidium bromide substrate in the presence and absence of standard efflux pump inhibitors. The minimum inhibitory concentration values were also compared to those of strains that do not overexpress these efflux pumps. In order to gain some insights about the efflux pump mechanisms of these chalcones, two homology models were created (NorA and MepA) for a docking procedure. In addition, the ADME properties (absorption, distribution, metabolism and excretion) were also evaluated. The tested chalcones promoted synergism of the norfloxacin antibiotic by inhibiting associated efflux pumps. All four tested chalcones appear to bind to the binding sites of the efflux pump models in the same fashion as other chalcones with efflux pump inhibition capabilities. It was also verified that the chalcones 1-4 are well absorbed in the intestine, but with a decrease in their bioavailability, resulting in a low volume of distribution in the blood plasma, in addition to having a mild CNS activity. However, the chalcone 3 and 4 were not toxic due to metabolic activation. Whereas the chalcones 1 and 2 present a mutagenic risk, depending on the oral dose administered. The tested chalcones have not antibacterial activity; however, they are capable of inhibiting efflux pumps for the 1199B and K2068 strains. They promoted synergism of the norfloxacin antibiotic by inhibiting associated efflux pumps, as well as other associated mechanisms.

Enhancement of the antibiotic activity by quercetin against Staphylococcus aureus efflux pumps.

The objective of this work was to evaluate the inhibitory effect of quercetin on S. aureus Efflux Pumps. The MIC of Quercetin was evaluated through the broth microdilution method, as well as the Efflux Pump inhibition assay through the method of reducing the antibiotic minimum inhibitory concentration as well as that of ethidium bromide. The in silico approach through bioinformatics was performed to demonstrate the molecular mechanism of interaction of the substrate and the binding cavity. The Quercetin inhibition concentration was not clinically relevant. With respect to the reversal of bacterial resistance effect by efflux pump inhibition, this effect was observed with the strains carrying the TetK and NorA pumps. Regarding the interaction between the Quercetin complex and the NorA pump, the extra stability was provided by hydrogen bonds produced by the hydroxyl group.

Modulation of Drug Resistance by Limonene: Inhibition of Efflux Pumps in Staphylococcus aureus Strains RN-4220 and IS-58.

AIMS: This study aimed to investigate the potential of limonene as an efflux pump (EP) inhibitor in Staphylococcus aureus strains, RN-4220 and IS-58, which carry EPs for erythromycin (MrsA) and tetracycline (TetK), respectively. BACKGROUND: The evolution of bacterial resistance mechanisms over time has impaired the action of most classes of antibiotics. Staphylococcus aureus is a notable bacterium, with high pathogenic potential and demonstrated resistance to conventional antibiotics. Considering the importance of discovering novel compounds to combat antibiotic resistance, our group previously demonstrated the antibacterial properties of limonene, a compound present in the essential oils of several plant species. OBJECTIVE: This study aimed to investigate the potential of limonene as an efflux pump (EP) inhibitor in Staphylococcus aureus strains RN-4220 and IS-58, which carry EPs for erythromycin (MrsA) and tetracycline (TetK), respectively. METHODS: The minimum inhibitory concentrations (MIC) of limonene and other efflux pump inhibitors were determined through the broth microdilution method. A reduction in the MIC of ethidium bromide was used as a parameter of EP inhibition. RESULT: While limonene was not shown to exhibit direct antibacterial effects against EP-carrying strains, in association with ethidium bromide and antibiotics, this compound demonstrated enhanced antibacterial activity, indicating the inhibition of the MrsA and TetK pumps. CONCLUSION: In conclusion, this pioneering study demonstrated the effectiveness of limonene as an EP inhibitor in S. aureus strains, RN-4220 and IS-58. Nevertheless, further studies are required to characterize the molecular mechanisms associated with limonene-mediated EP inhibition.

Clinical pharmacy in onco-hematology and bone marrow transplant: A valuable contribution to improving patient safety.

INTRODUCTION: It is known that clinical pharmacists intercept prescribing errors and contribute to patient safety in several medical specialties. The aim of this study was to identify, quantify and classify prescribing errors and pharmacist interventions carried out in onco-hematology and bone marrow transplant inpatient units. METHODS: This was a prospective and quantitative study, conducted from February 2018 to July 2018 in onco-hematology and bone marrow transplant inpatient units of a tertiary teaching hospital in Brazil. A pharmacist detected prescribing errors and performed interventions. The type and incidence of prescribing errors, error severity, type of pharmacist interventions, potential impact of interventions in patient care, and intervention acceptance rates were evaluated. RESULTS: A total of 1172 prescriptions were evaluated, 9% of them contained errors (total of 135 errors), and the most common error was related to prescribing the wrong dose (31.8%). Wrong dose and omission of drug were the two most frequent errors in onco-hematology, while wrong dose followed by inappropriate dilution were the most frequent in bone marrow transplantation. The pharmacist performed 135 interventions and the most common intervention was related to the treatment regimen (41.5%). Serious errors and very significant pharmacist interventions were the most frequent in both inpatient units. The acceptance rate of pharmacist interventions was high (90%). CONCLUSIONS: Clinical pharmacy improves patient safety and quality of care in onco-hematology and bone marrow transplant inpatient units.

Inhibition of Efflux Pumps by Monoterpene (α-pinene) and Impact on Staphylococcus aureus Resistance to Tetracycline and Erythromycin.

INTRODUCTION: Infectious diseases have been responsible for an increasing number of deaths worldwide. Staphylococcus aureus has been recognized as one of the most notable causative agents of severe infections, while efflux pump (EP) expression is one of the main mechanisms associated with S. aureus resistance to antibiotics. OBJECTIVE: This study aimed to investigate the potential of &#945;-pinene as an efflux pump inhibitor in species of S. aureus carrying the TetK and MrsA proteins. METHODS: The minimum inhibitory concentrations (MIC) of &#945;-pinene and other efflux pump inhibitors were assessed using serial dilutions of each compound at an initial concentration above 1024 µg/mL. Solutions containing culture medium and bacterial inoculums were prepared in test tubes and subsequently transferred to 96-well microdilution plates. The modulation of ethidium bromide (EtBr) and antibiotics (tetracycline and erythromycin) was investigated through analysis of the modification in their MICs in the presence of a subinhibitory concentration of &#945;-pinene (MIC/8). Wells containing only culture medium and bacterial inoculums were used as negative control. Carbonyl cyanide m-chlorophenylhydrazone (CCCP) was used as a positive control. RESULTS: The MIC of ethidium bromide against S. aureus strains RN-4220 and IS-58 was reduced by association with α-pinene. This monoterpene potentiated the effect of tetracycline against the IS-58 strain but failed in modulating the antibacterial effect of erythromycin against RN-4220, suggesting a selective inhibitory effect on the TetK EP by &#945;- pinene. CONCLUSION: In conclusion, α-pinene has promising effects against S.aureus strains, which should be useful in the combat of antibacterial resistance associated with EP expression. Nevertheless, further research is required to fully characterize its molecular mechanism of action as an EP inhibitor.

Parkia platycephala lectin enhances the antibiotic activity against multi-resistant bacterial strains and inhibits the development of Haemonchus contortus.

Lectins have been studied in the past few years as an alternative to inhibit the development of pathogenic bacteria and gastrointestinal nematodes of small ruminants. The development of new antibacterial and anthelmintic compounds is necessary owing to the increase in drug resistance among important pathogens. Therefore, this study aimed to evaluate the capacity of a glucose/mannose-binding lectin from Parkia platycephala seeds (PPL) to inhibit the development of Haemonchus contortus and to modulate antibiotic activity against multi-resistant bacterial strains, thereby confirming its efficacy when used in combination with gentamicin. PPL at the concentration of 1.2 mg/mL did not show inhibitory activity on H. contortus in the egg hatch test or the exsheathment assay. However, it did show significant inhibition of H. contortus larval development with an IC50 of 0.31 mg/mL. The minimum inhibitory concentration (MIC) obtained for PPL against all tested bacterial strains was not clinically relevant (MIC ≥ 1024 µg/mL). However, when PPL was combined with gentamicin, a significant increase in antibiotic activity was observed against S. aureus and E.coli multi-resistant strains. The inhibition of hemagglutinating activity by gentamicin (MIC = 50 mM) revealed that it may be interacting with the carbohydrate-binding site of PPL. It is this interaction between the antibiotic and lectin carbohydrate-binding site that may be responsible for the enhanced activity of gentamicin against multi-resistant strains. It can be concluded that PPL showed selective anthelmintic effect, inhibiting the development of H. contortus larvae and that it increased the effect of the antibiotic gentamicin against multi-resistant bacterial strains, thus constituting a potential therapeutic resource against resistant bacterial strains and H. contortus.

Clinical oncology pharmacist: Effective contribution to patient safety.

Management and prevention of problems related to oncology drugs are particularly important due to the excessive cost, high toxicity, and narrow therapeutic index of the antineoplastic drugs, in addition to the patients' state of health. Therefore, the presence of the pharmacist as a member of the multidisciplinary team is essential to contribute to patient safety. In this work, the interventions performed were identified, quantified, and classified to characterize the work of the clinical oncology pharmacist. This is a prospective and quantitative study, conducted over a period of six months in the outpatient oncology and chemotherapy clinic of the University Hospital of the University of Campinas, Brazil. A total of 3526 medical prescriptions were evaluated for the 780 patients seen and, among these prescriptions, 220 (6.24%) contained errors, representing 6.24% of the total number. The most common error was dose-related with 79 (22.83%) cases of overdosing. Wrong-patient medication error was the least reported (0.29%). Thirty drugs were involved in the pharmaceutical interventions, Carboplatin and Ondansetron being the most frequent. Thirteen types of potential errors were evaluated according to the method proposed by Cardinal and Fernandes. Two (15.38%) included interventions of indication, contraindication, and therapeutic efficacy of a drug. Five of them (38.46%) are related to the treatment regimen, and two (15.38%) were related to prevention of potential adverse events. Four interventions (30.77%) concerned technical interventions in injectable drugs such as dilution, compatibility, and administration time. Of the 346 interventions performed, 1 (0.29%) was classified as potentially lethal, 114 as serious (32.95%), 140 as significant (40.46%), and 91 as minor (26.30%).