Advancing Precision Medicine: A Review of Innovative In Silico Approaches for Drug Development, Clinical Pharmacology and Personalized Healthcare.

The landscape of medical treatments is undergoing a transformative shift. Precision medicine has ushered in a revolutionary era in healthcare by individualizing diagnostics and treatments according to each patient's uniquely evolving health status. This groundbreaking method of tailoring disease prevention and treatment considers individual variations in genes, environments, and lifestyles. The goal of precision medicine is to target the "five rights": the right patient, the right drug, the right time, the right dose, and the right route. In this pursuit, in silico techniques have emerged as an anchor, driving precision medicine forward and making this a realistic and promising avenue for personalized therapies. With the advancements in high-throughput DNA sequencing technologies, genomic data, including genetic variants and their interactions with each other and the environment, can be incorporated into clinical decision-making. Pharmacometrics, gathering pharmacokinetic (PK) and pharmacodynamic (PD) data, and mathematical models further contribute to drug optimization, drug behavior prediction, and drug-drug interaction identification. Digital health, wearables, and computational tools offer continuous monitoring and real-time data collection, enabling treatment adjustments. Furthermore, the incorporation of extensive datasets in computational tools, such as electronic health records (EHRs) and omics data, is also another pathway to acquire meaningful information in this field. Although they are fairly new, machine learning (ML) algorithms and artificial intelligence (AI) techniques are also resources researchers use to analyze big data and develop predictive models. This review explores the interplay of these multiple in silico approaches in advancing precision medicine and fostering individual healthcare. Despite intrinsic challenges, such as ethical considerations, data protection, and the need for more comprehensive research, this marks a new era of patient-centered healthcare. Innovative in silico techniques hold the potential to reshape the future of medicine for generations to come.

Exploring the Role of Drug Repurposing in Bridging the Hypoxia-Depression Connection.

High levels of oxidative stress are implicated in hypoxia, a physiological response to low levels of oxygen. Evidence supports a connection between this response and depression. Previous studies indicate that tryptophan hydroxylase can be negatively affected in hypoxia, impairing serotonin synthesis and downstream pathways. Some studies also hypothesize that increasing hypoxia-inducible factor-1 (HIF-1) levels may be a new therapeutic modality for depression. Hence, this study delved into the influence of hypoxia on the cellular response to drugs designed to act in depression. By the induction of hypoxia in SH-SY5Y cells through a hypoxia incubator chamber or Cobalt Chloride treatment, the effect of Mirtazapine, an antidepressant, and other drugs that interact with serotonin receptors (TCB-2, Dextromethorphan, Ketamine, Quetiapine, Scopolamine, Celecoxib, and Lamotrigine) on SH-SY5Y cellular viability and morphology was explored. The selection of drugs was initially conducted by literature search, focusing on compounds with established potential for employment in depression therapy. Subsequently, we employed in silico approaches to forecast their ability to traverse the blood-brain barrier (BBB). This step was particularly pertinent as we aimed to assess their viability for inducing potential antidepressant effects. The effect of these drugs in hypoxia under the inhibition of HIF-1 by Echinomycin was also tested. Our results revealed that all the potential repurposed drugs promoted cell viability, especially when hypoxia was chemically induced. When combined with Echinomycin, all drugs decreased cellular viability, possibly by the inability to interact with HIF-1.

The elusive Luminal B breast cancer and the mysterious chemokines.

PURPOSE: Invasive ductal breast cancer (IDC) is heterogeneous. Staging and immunohistochemistry (IH) allow for effective therapy but are not yet ideal. Women with Luminal B tumors show an erratic response to treatment. This prospective study with 81 women with breast cancer aims to improve the prognostic stratification of Luminal B patients. METHODS: This is a prospective translational study with 81 women with infiltrating ductal carcinoma, grouped by TNM staging and immunohistochemistry, for survival analysis, and their correlations with the chemokines. Serum measurements of 13 chemokines were performed, including 7 CC chemokines [CCL2(MCP1), CCL3(MIP1α), CCL4(MIP1ß), CCL5(Rantes), CCL11(Eotaxin), CCL17(TARC), CCL20(MIP3α)], 6 CXC chemokines [CXCL1(GroAlpha), CXCL5(ENA78), CCXCL8(IL-8), CXCL9(MIG), CXCL10(IP10), CXCL11(ITAC)]. RESULTS: Overall survival was significantly dependent on tumor staging and subtypes by immunohistochemistry, with a median follow-up time the 32.87 months (3.67-65.63 months). There were age correlations with IP10/CXCL10 chemokines (r = 0.4360; p = 0.0079) and TARC/CCL17 (Spearman + 0.2648; p = 0.0360). An inverse correlation was found between body weight and the chemokines Rantes/CCL5 (r = - 0.3098; p = 0.0169) and Eotaxin/CCL11 (r = - 0.2575; p = 0.0470). Smokers had a higher concentration of MIP3α/CCL20 (Spearman + 0.3344; p = 0.0267). Luminal B subtype patients who expressed lower concentrations of ENA78/CXCL5 (≤ 254.83 pg/ml) (Log-Rank p = 0.016) and higher expression of MIP1ß/CCL4 (> 34.84 pg/ml) (Log-Rank p = 0.014) had a higher risk of metastases. CONCLUSION: Patients with Luminal B breast tumors can be better stratified by serum chemokine expression, suggesting that prognosis is dependent on biomarkers other than TNM and IH.

Prediction of CYP-Mediated Drug Interaction Using Physiologically Based Pharmacokinetic Modeling: A Case Study of Salbutamol and Fluvoxamine.

Drug-drug interactions (DDIs) represent a significant concern in healthcare, particularly for patients undergoing polytherapy. DDIs can lead to a range of outcomes, from decreased therapeutic effectiveness to adverse effects. Salbutamol, a bronchodilator recommended for the treatment of respiratory diseases, is metabolized by cytochrome P450 (CYP) enzymes, which can be inhibited or induced by co-administered drugs. Studying DDIs involving salbutamol is crucial for optimizing drug therapy and preventing adverse outcomes. Here, we aimed to investigate CYP-mediated DDIs between salbutamol and fluvoxamine through in silico approaches. The physiologically based pharmacokinetic (PBPK) model of salbutamol was developed and validated using available clinical PK data, whereas the PBPK model of fluvoxamine was previously verified by GastroPlus. Salbutamol-fluvoxamine interaction was simulated according to different regimens and patient's characteristics (age and physiological status). The results demonstrated that co-administering salbutamol with fluvoxamine enhanced salbutamol exposure in certain situations, especially when fluvoxamine dosage increased. To sum up, this study demonstrated the utility of PBPK modeling in predicting CYP-mediated DDIs, making it a pioneer in PK DDI research. Furthermore, this study provided insights into the relevance of regular monitoring of patients taking multiple medications, regardless of their characteristics, to prevent adverse outcomes and for the optimization of the therapeutic regimen, in cases where the therapeutic benefit is no longer experienced.

The Involvement of Hypoxia in the Response of Neuroblastoma Cells to the Exposure of Atorvastatin.

Cancer is a set of complex diseases, being one of the leading causes of death worldwide. Despite a lot of research on the molecular pathways and effective treatments, there are still huge gaps. Indeed, the development of new anti-cancer drugs is a complex process. To face this problem, drug repurposing is being increasingly applied. This approach aims to identify new indications for already approved drugs. In this regard, statins (clinically used for reducing cholesterol levels) are reported to induce anti-cancer effects, particularly by inducing apoptosis and altering the tumor microenvironment. Atorvastatin is a type of statin with several potentialities as an anti-cancer agent, supported by several studies. Our study aimed to explore the effect of this drug in SH-SY5Y human neuroblastoma cells. Additionally, we also aimed to understand how this drug acts under hypoxia and the inhibition of hypoxia-inducible factor-1 (HIF-1). For that purpose, we assessed cellular viability/morphology after exposure to different concentrations of atorvastatin, with or without chemically induced hypoxia with chloride cobalt (CoCl2) and with or without echinomycin (HIF-1α inhibitor). Our results supported the cytotoxic effects of atorvastatin. Additionally, we also revealed that besides these effects, under hypoxia, this drug induced proliferation of the neuroblastoma cells, supporting the importance of different stimuli and environment on the effect of drugs on cancer cells.

The Effects of Chitosan on the Healing Process of Oral Mucosa: An Observational Cohort Feasibility Split-Mouth Study.

The healing process is a dynamic process accompanied by some classical symptoms of inflammation such as redness, swelling, pain, and loss of function. Chitosan is a natural polymer with properties that contribute to tissue healing, with properties that could be applied in periodontal therapy, such as the wound healing of oral mucosa. This experimental split-mouth study aims to assess the possibilities of chitosan influencing the healing process of oral mucosa in eight patients, where the studied group was subjected to two oral surgeries: one with chitosan hydrogel into the socket and other without the biomaterial. A semi-quantitative analysis of the data was performed. Some classic signs of inflammation in a short period of time were observed where chitosan acted, compared to the control. An absence of bleeding was observed in the chitosan cases. According to the literature, chitosan recruits and activates neutrophils and macrophages and stimulates angiogenesis. Hemostatic and antimicrobial activity of chitosan also play an important role in wound healing. Chitosan seems to improve the postoperative quality of patients, allowing rapid wound healing with less complications.

Salbutamol in the Management of Asthma: A Review.

Asthma is a common inflammatory disease of the lungs. The prevalence of asthma is increasing worldwide, and the tendency indicates that the number of asthma sufferers will soar in the coming years for several reasons, in particular, the lifestyles we have adopted that expose us to risk factors. Salbutamol is the first selective short-acting ß2-agonist (SABA) used as an alternative reliever in the treatment of asthma. Its therapeutic effect is based on its potent smooth muscle relaxant properties, which allow the inhibition of bronchial smooth muscle contraction and subsequent bronchodilation. Salbutamol can be administered orally, intravenously (IV), intramuscularly (IM), subcutaneously, or by inhalation. For this reason, the pharmacokinetic (PK) parameters-absorption, distribution, metabolism, and elimination-are highly diverse and, consequently, the efficacy and adverse effects also differ between each formulation. Here, we review the pharmacological profile of different salbutamol formulations, focusing on their efficacy and adverse effects for its original application, asthma.

Therapeutic Options for Chlamydia trachomatis Infection: Present and Future.

Sexually transmitted infections (STIs), such as Chlamydia trachomatis (Ct) infection, have serious consequences for sexual and reproductive health worldwide. Ct is one of the most common sexually transmitted bacterial infections in the world, with approximately 129 million new cases per year. C. trachomatis is an obligate intracellular Gram-negative bacterium. The infection is usually asymptomatic, notwithstanding, it could also be associated with severe sequels and complications, such as chronic pain, infertility, and gynecologic cancers, and thus there is an urgent need to adequately treat these cases in a timely manner. Consequently, beyond its individual effects, the infection also impacts the economy of the countries where it is prevalent, generating a need to consider the hypothesis of implementing Chlamydia Screening Programs, a decision that, although it is expensive to execute, is a necessary investment that unequivocally will bring financial and social long-term advantages worldwide. To detect Ct infection, there are different methodologies available. Nucleic acid amplification tests, with their high sensitivity and specificity, are currently the first-line tests for the detection of Ct. When replaced by other detection methods, there are more false negative tests, leading to underreported cases and a subsequent underestimation of Ct infection's prevalence. Ct treatment is based on antibiotic prescription, which is highly associated with drug resistance. Therefore, currently, there have been efforts in line with the development of alternative strategies to effectively treat this infection, using a drug repurposing method, as well as a natural treatment approach. In addition, researchers have also made some progress in the Ct vaccine development over the years, despite the fact that it also necessitates more studies in order to finally establish a vaccination plan. In this review, we have focused on the therapeutic options for treating Ct infection, expert recommendations, and major difficulties, while also exploring the possible avenues through which to face this issue, with novel approaches beyond those proposed by the guidelines of Health Organizations.

Epidermal growth factor receptor (EGFR) expression in the serum of patients with triple-negative breast carcinoma: prognostic value of this biomarker.

Background: Epidermal growth factor receptor (EGFR) overexpression has been considered a poor prognostic factor in breast cancer. Methodology: A prospective study of 206 women with breast cancer analysed by stages (I, II, III and IV) and by immunohistochemical subtype (Luminal A, Luminal B, HER2+ and triple-negative (TN)); 89 healthy controls with normal recent mammography were included. The EGFR measured in the serum (sEGFR) was detected by the Enzyme-Linked Immunosorbent Assay (ELISA) method (R&D Systems kit DY231) collected by blood before any treatment in patients. Kaplan-Meier method and Cox regression were carried out to obtain the prognostic value, considering significance if p < 0.05. Results: With a median follow-up of 36.6 months, 47 deaths occurred. Multivariable Cox regression showed difference of overall survival (OS) associated with sEGFR levels (sEGFR ≤ or > 47.8 ng/mL) in patients with TN cancers, but not of Luminal A, Luminal B or HER2+ subtypes; adjusted by stage, the death risk increased by approximately 415% [hazard ratio (HR): 5.149 (1.900-13.955), p = 0.001] for patients with sEGFR > 47.8 ng/mL compared to patients with a lower sEGFR value. There was no significant correlation of sEGFR with staging, histological tumour grade (G1/G2/G3), Ki67 (< or ≥14%) or body mass index. Conclusions: Increased sEGFR expression in patients with TN tumours is a significant predictor of lower OS and its quantification is inexpensive and straightforward.

New Data for Nebivolol after In Silico PK Study: Focus on Young Patients and Dosage Regimen.

Nebivolol (NEB) is a highly selective ß1 receptor antagonist with a distinct pharmacological profile. This drug is approved for the treatment of hypertension in the US, and hypertension and heart failure in Europe. Here, we review observations based on age dependence and explore new drug regimens with in-silico studies, to achieve better efficacy and safety. The clinical data were obtained from six published literature reports. Then the data were used for model building, evaluation, and simulation. A two-compartment model with first-order absorption, lag time, linear elimination, and the following covariates: age and genotype were the ones best describing our population. Simulation of different dose regimens resulted in an increase chance of efficacy and safety when the dose regimen was altered to 6 mg every 36 h. It is worth noting that our population in this study constituted of young and healthy individuals. Studies regarding the effects of NEB according to age are scarce; however, they are needed to further improve efficacy and safety, and reduce adverse effects.

The effect of delayed treatment in breast cancer patients: How much is too late? An experience of a single-center study effect of surgery delay in survival.

BACKGROUND AND OBJECTIVES: Proper treatment is critical for control and curative intent in breast cancer. Delays in receiving treatment can influence patients' prognoses. METHODS: Retrospective, observational, single-center study based on data from medical records of 747 patients with non-metastatic invasive ductal breast carcinoma (I-III) in the initial analysis, comprising 554 patients undergoing adjuvant and 193 neoadjuvant treatment. Kaplan-Meier, Cox regression and time-dependent Cox regression were performed to obtain the predictive value of time to surgery and time to first treatment. Immortal time bias was managed and only 721 patients were included in the multivariable analysis. RESULTS: During a median observation of 64.4 months, there were 140 death events and 177 disease progression events. Time to surgery (TTS) and time from completion of neoadjuvant chemotherapy to surgery (TNS) showed a significant impact on overall survival, associated with a 6% increased chance of death [HR: 1.06 (1.03-1.09), p < 0.001] and 4% [HR: 1.04 (1.00-1.09), p = 0.048] with a one-month increment, respectively. By multivariable analysis, continuous TTS had a different weight as a prognostic factor in stage IIIA/IIIB [adjusted HR: 1.249 (1.072-1.454), p = 0.004] compared to stage I/II [adjusted HR: 1.093 (1.048-1.141), p < 0.0005]. Likewise, TNS was significant after adjusting for other factors [adjusted HR: 1.092 (1.038-1.148), p = 0.001]. CONCLUSION: Delay in receiving surgery with curative intent impairs the survival of patients with breast cancer.

A hierarchical approach to combine histological grade and immunohistochemical factors to identify high-risk luminal breast cancers.

Background: The luminal subtype accounts for ~70% of newly diagnosed breast cancer patients. Although it has a better prognosis, approximately 30% of them develop a late relapse. Identifying those patients is of interest to improve treatment decisions. Methods: A retrospective observational, single-centre study based on data from medical records of 572 non-metastatic (I-III) invasive ductal breast carcinoma patients, 448 with luminal tumours and 124 with triple-negative tumours. Kaplan-Meier, Cox regression and time-dependent Cox regression were carried out to obtain the prognosis value of risk factors. Results: During a median observation of 5.5 years, 105 distant metastasis events and 105 all-cause deaths were observed. In addition to known clinicopathological factors (i.e., age, tumour size and lymph node metastasis), the high semi-quantitative expression of both hormone receptors was associated with distant metastasis-free survival (DMFS) (adjusted hazard ratio (HaR): 0.524 (0.316-0.867), p = 0.012) and overall survival (OS) (adjusted HaR: 0.486 (0.286-0.827), p = 0.008). The stratified analysis made it possible to identify risk modification factors. Subsequent stratification by histological grade, Ki-67 and semi-quantitative PR expression or, mainly, the composite semi-quantitative expression of hormone receptors (cHR) enabled the identification of luminal breast cancer patients of adjuvant schema at higher risk for metastasis and death. However, initial analyses including patients of neoadjuvant therapy pointed to a path of subsequent stratification by cHR and histological grade, also enabling grouping of luminal breast cancer patients with similar prognosis for DMFS (cHR ≤ 4+ G2 or G3 versus triple-negative, adjusted HaR: 0.703 (0.415-1.189), p = 0.189) and OS (cHR ≤4+ G2 or G3 versus triple-negative, adjusted HaR: 0.662 (0.403-1.088), p = 0.104). Conclusion: The semi-quantitative expression of both cHR, Ki-67 proliferation index and histological grade can identify luminal breast cancer patients at greater risk of developing metastasis and death when combined in a hierarchical fashion, and could be useful for a better prognosis stratification in services from low- and middle-income countries.

Prognosis value of lymphovascular invasion in patients with invasive ductal breast carcinoma according to lymph node metastasis status.

Background: Tumour lymphovascular invasion is not routinely assessed in all pathology services, and whether reporting it quantitatively or qualitatively is the main factor associated with the loss of this prognostic event. This study aimed to analyse the prognostic value of qualitatively reported lymphovascular invasion in patients with invasive breast ductal carcinoma. Methods: This was a retrospective, single-center study, enrolling a total of 426 patients with invasive ductal carcinoma of the breast with a report of lymphovascular invasion, with a median follow-up of approximately 4.5 years. Kaplan-Meier and Cox regression was performed to obtain the predictive value of lymphovascular invasion. Propensity score matching was performed to reduce bias by standardising factors with significant differential distribution of lymphovascular invasion status. Results: Lymphovascular invasion was present in 197 (49.2%) patients. Multivariate Cox regression showed that lymphovascular invasion independently increases the risk of death by almost two times (adjusted hazard ratio (HR): 2.045 (1.226-3.406), p = 0.006) and the risk of distant metastasis by more than two times (adjusted HR: 2.373 (1.404-4.010), p = 0.001). Subgroup analysis after matching by propensity score in adjuvant-only patients showed that the lymphovascular invasion is a factor of increased death in N- patients (adjusted HR: 12.597 (1.624-97.728), p = 0.015) and of distant metastasis-free survival in N+ patients (adjusted HR: 4.862 (1.649-14.335), p = 0.004) and almost for N- patients (adjusted HR 7.905 (0.969-64.509), p = 0.004). Conclusion: The presence of lymphovascular invasion is a predictor of worse prognosis in patients with invasive ductal carcinoma of the breast, even with metastatic lymph node disease (N1-N3).

The benefits of trastuzumab in the treatment of HER2+ breast cancer as a function of exposure time.

BACKGROUND: Breast cancer is a heterogeneous disease with overexpression of several receptors, such as human epidermal receptor 2 (HER2), which is a prognostic and predictive biomarker for treatment with the anti-HER2 monoclonal antibody trastuzumab. This study aimed to test the contribution of this regimen in patients with overexpression/amplification of HER2 for periods shorter than the 1-year treatment recommendation. METHODS: A retrospective single-centre study involving 155 patients with non-metastatic (stages I-III) invasive ductal HER2+ breast carcinoma, with a median follow-up of 48.9 months after completion of adjuvant therapy, except endocrine therapy. RESULTS: About 60% of patients received trastuzumab therapy for a median time of 365 days. Although the use of trastuzumab for a short period has provided some benefit, analyses of survival with a continuous dependent variable have revealed a minimum time for improved survival. In the multivariate analysis by Cox regression, trastuzumab use duration exceeding 9 weeks resulted in protection against distant metastasis (adjusted HR: 0.307 (0.139-0.678), p = 0.004), disease progression (adjusted hazard ratio (HR) 0.353 (0.175-0.714), p = 0.004) and death (adjusted HR: 0.267 (0.105-0.678), p = 0.005), being superior to multimodal systemic therapy with chemotherapy and to endocrine therapy without trastuzumab, but inferior to almost 1 year of administration of this monoclonal antibody, especially regarding overall survival (adjusted HR: 0.203 (0.069-0.596), p = 0.004). CONCLUSION: Despite showing some benefits, the protective effect derived from a suboptimal time of trastuzumab exposure is inferior to the standard course of 1 year.

Inanimate Surfaces and Air Contamination with Multidrug Resistant Species of Staphylococcus in the Neonatal Intensive Care Unit Environment.

BACKGROUND: Contamination of the hospital environment with multi-resistant (MDR) Staphylococcus increases the risk of infection. The aim of this study is to identify the MDR species of Staphylococcus on inanimate surfaces, in air, and in clinical samples, and analyze the risk factors that correlate with the occurrence of infections in a Neonatal Intensive Care Unit. METHODS: Samples of inanimate surfaces and air were taken using a premoistened swab (0.9% sodium chloride) and spontaneous air sedimentation, respectively. The clinical isolates were recovered from infected neonates. The isolates (environmental and clinical) were identified by matrix-assisted laser desorption ionization-time of flight and the resistance profile was calculated using the disk diffusion agar technique. RESULTS: In total, 181 isolates were obtained, 93 from (surfaces), 18 from the air, and 70 clinical samples. S. epidermidis was the most frequent species (66.8%), and the failure rate in air cleaning was 100%. More than 60% of the isolates were MDR, and the majority of clinical isolates (60.4%) had a resistance profile identical to that of the environmental isolates. CONCLUSION: Staphylococcus spp. were found in most of the analyzed samples, with a high frequency of MDR isolates, demonstrating the importance of the hospital environment as a reservoir, and the need for infection control measures, and rational use of antimicrobials.

The effectiveness of radiotherapy in preventing disease recurrence after breast cancer surgery.

BACKGROUND AND OBJECTIVES: The locoregional management of breast cancer has a critical impact on prognosis. This study aimed to analyze the effectiveness of radiotherapy against the deleterious effect of positive surgical margins on disease outcomes. METHODS: Retrospective, single-center study enrolled 721 breast cancer patients with a median follow-up of approximately 64.50 months (3.67-247.40). Analyses were performed considering the end of adjuvant therapy, except endocrine therapy. Kaplan-Meier and Cox regression were performed to obtain the predictive value of treatments. RESULTS: The minimally adequate radiotherapy (≥45 cGy) was associated with improved outcomes in breast cancer patients compared to inadequate radiotherapy (<45 cGy/no) by controlling locoregional relapses and distant metastasis. In patients with positive surgical margins (n = 53), radiotherapy was associated with an approximate decrease of 90% in locoregional relapse risk [adjusted HR: 0.108 (0.012-0.932), p = 0.043]. Radiotherapy did not alter the adverse effect of positive surgical margins, especially in patients with a higher risk of poorly differentiated tumors (n = 146), presence of lymphovascular invasion (n = 163), and triple-negative subtype (n = 113). Notwithstanding, radiotherapy was associated with respective decreases of distant metastasis risk of 75.2% [adjusted HR: 0.248 (0.081-0.762), p = 0.015] and 67.8% [adjusted HR: 0.322 (0.101-1.029), p = 0.056] in patients with triple-negative tumors or with lymphovascular invasion. CONCLUSION: Adequate radiotherapy is associated with better outcomes in breast cancer. Despite improving locoregional relapse-free survival, radiotherapy does not ablate positive surgical margins, a factor of poorer prognosis that prevails mainly in patients with factors of higher relapse risk.

Prediction of Drug Synergism between Peptides and Antineoplastic Drugs Paclitaxel, 5-Fluorouracil, and Doxorubicin Using In Silico Approaches.

Chemotherapy is the main treatment for most early-stage cancers; nevertheless, its efficacy is usually limited by drug resistance, toxicity, and tumor heterogeneity. Cell-penetrating peptides (CPPs) are small peptide sequences that can be used to increase the delivery rate of chemotherapeutic drugs to the tumor site, therefore contributing to overcoming these problems and enhancing the efficacy of chemotherapy. The drug combination is another promising strategy to overcome the aforementioned problems since the combined drugs can synergize through interconnected biological processes and target different pathways simultaneously. Here, we hypothesized that different peptides (P1-P4) could be used to enhance the delivery of chemotherapeutic agents into three different cancer cells (HT-29, MCF-7, and PC-3). In silico studies were performed to simulate the pharmacokinetic (PK) parameters of each peptide and antineoplastic agent to help predict synergistic interactions in vitro. These simulations predicted peptides P2-P4 to have higher bioavailability and lower Tmax, as well as the chemotherapeutic agent 5-fluorouracil (5-FU) to have enhanced permeability properties over other antineoplastic agents, with P3 having prominent accumulation in the colon. In vitro studies were then performed to evaluate the combination of each peptide with the chemotherapeutic agents as well as to assess the nature of drug interactions through the quantification of the Combination Index (CI). Our findings in MCF-7 and PC-3 cancer cells demonstrated that the combination of these peptides with paclitaxel (PTX) and doxorubicin (DOXO), respectively, is not advantageous over a single treatment with the chemotherapeutic agent. In the case of HT-29 colorectal cancer cells, the combination of P2-P4 with 5-FU resulted in synergistic cytotoxic effects, as predicted by the in silico simulations. Taken together, these findings demonstrate that these CPP6-conjugates can be used as adjuvant agents to increase the delivery of 5-FU into HT-29 colorectal cancer cells. Moreover, these results support the use of in silico approaches for the prediction of the interaction between drugs in combination therapy for cancer.

Impact of alcohol gel on hand bacteria in healthcare professionals / Impacto del gel de alcohol en las bacterias de las manos en los profesionales sanitarios / Impacto do álcool gel nas bactérias das mãos de profissionais de saúde

Background and objectives: Healthcare-Associated Infections are a problem reported by hospitals worldwide, increasing patient morbidity and mortality, prolonging hospitalization, and increasing health care costs. The hands of health professionals are still the main source of infections, making hand hygiene extremely important for spreading infection control. The objective of this study was to analyze the presence of bacteria on the hands of health professionals after hygiene with alcohol gel in a Neonatal Unit and describe the resistance of microorganisms to antimicrobials. Methods: Hand samples were collected using the modified glove-juice method on both occasions, before and after hand hygiene with alcohol gel. Bacteria were identified by MALDI-TOF and susceptibility tests according to Clinical and Laboratory Standards Institute document M100-E29. Results: A total of 214 samples were obtained, of which 104 (48.6%) showed bacterial growth before hand hygiene and 52 (24.3%) after hand hygiene with alcohol gel. There were 217 isolates from the cultures, of which coagulase-negative Staphylococcus was the most frequent with 41 (27.2%) and 24 (36.4%) positive cultures, respectively before and after hand hygiene. The second most frequent microorganism was Klebsiella pneumoniae with 32 (21.2%) and 16 (24.2%), respectively before and after hand hygiene. Multidrug resistance to antimicrobials was detected in 58.1% of gram-positive bacteria and in 34.3% of gram-negative bacteria. Conclusion: A decrease was observed, but not an elimination of the microbial load after hand hygiene with alcohol gel, demonstrating the need for improvements in hand hygiene.(AU)

Justificativa e objetivos: As Infecções Relacionadas à Assistência à Saúde são um problema relatado por hospitais em todo o mundo, aumentando a morbimortalidade dos pacientes, prolongando a hospitalização e aumentando os custos dos cuidados de saúde. As mãos dos profissionais de saúde ainda são a principal fonte de infecções, tornando a higienização das mãos extremamente importante para a disseminação do controle de infecções. O objetivo deste estudo foi analisar a presença de bactérias nas mãos de profissionais de saúde após higienização com álcool gel em uma Unidade Neonatal e descrever a resistência dos microrganismos aos antimicrobianos. Métodos: Amostras de mãos foram coletadas pelo método luva-suco modificado em ambas as ocasiões, antes e após a higienização das mãos com álcool gel. As bactérias foram identificadas por MALDI-TOF e testes de suscetibilidade de acordo com o documento M100-E29 do Clinical and Laboratory Standards Institute. Resultados: Obteve-se um total de 214 amostras, das quais 104 (48,6%) apresentaram crescimento bacteriano antes da higienização das mãos e 52 (24,3%) após a higienização das mãos com álcool gel. Foram 217 isolados das culturas, sendo Staphylococcus coagulase-negativo o mais frequente com 41 (27,2%) e 24 (36,4%) culturas positivas, respectivamente antes e após a higienização das mãos. O segundo microrganismo mais frequente foi Klebsiella pneumoniae com 32 (21,2%) e 16 (24,2%), respectivamente antes e após a higienização das mãos. A multirresistência aos antimicrobianos foi detectada em 58,1% das bactérias gram-positivas e em 34,3% das bactérias gram-negativas. Conclusão: Observou-se diminuição, mas não eliminação da carga microbiana após higienização das mãos com álcool gel, demonstrando a necessidade de melhorias na higienização das mãos.(AU)

Justificación y objetivos: Las Infecciones Asociadas a la Atención de la Salud son un problema reportado por los hospitales a nivel mundial, aumentando la morbimortalidad de los pacientes, prolongando la hospitalización y aumentando los costos de la atención médica. Las manos de los profesionales de la salud siguen siendo la principal fuente de infecciones, por lo que la higiene de manos es extremadamente importante para el control de infecciones. El objetivo de este estudio fue analizar la presencia de bacterias en las manos de los profesionales de la salud después de la higiene con alcohol en gel en una Unidad Neonatal y describir la resistencia de los microorganismos a los antimicrobianos. Métodos: Se recogieron muestras de manos mediante el método guante-jugo modificado en ambas ocasiones, antes y después de la higiene de manos con alcohol en gel. Las bacterias se identificaron mediante MALDI- -TOF y pruebas de susceptibilidad de acuerdo con el documento M100-E29 del Clinical and Laboratory Standards Institute. Resultados: Se obtuvieron un total de 214 muestras, de las cuales 104 (48,6%) presentaron crecimiento bacteriano antes de la higiene de manos y 52 (24,3%) después de la higiene de manos con alcohol en gel. Hubo 217 aislamientos de los cultivos, de los cuales el Staphylococcus coagulasa negativo fue el más frecuente con 41 (27,2%) y 24 (36,4%) cultivos positivos, respectivamente antes y después de la higiene de manos. El segundo microorganismo más frecuente fue Klebsiella pneumoniae con 32 (21,2%) y 16 (24,2%), respectivamente antes y después de la higiene de manos. Se detectó multirresistencia a los antimicrobianos en el 58,1% de las bacterias grampositivas y en el 34,3% de las bacterias gramnegativas. Conclusión: Se observó una disminución, pero no una eliminación de la carga microbiana después de la higiene de manos con alcohol en gel, lo que demuestra la necesidad de mejoras en la higiene de manos.(AU)

Quantification of biofilm produced by clinical, environment and hands' isolates Klebsiella species using colorimetric and classical methods.

Some species of Klebsiella, such as Klebsiella pneumoniae and Klebsiella oxytoca, are important nosocomial pathogens frequently involved in outbreaks in Neonatal Intensive Care Units (NICU) and have the ability to form a biofilm. This study aims to evaluate the biofilm production of K. pneumoniae and K. oxytoca isolates collected from the hands of health professionals, neonates' blood and the environment of a Brazilian NICU, using three colorimetric methods and a classical method of counting the colony-forming units and compare the analysis among these techniques. The biofilm formation was carried out by the microplate technique, using three colorimetric assays: crystal violet, safranin and 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl) -5 [(phenylamino) arbonyl] - 2H-tetrazolium hydroxide (XTT). Also, colony-forming units were determined. Twenty-eight isolates of K. pneumoniae were collected from the blood, hands and environment and five of K. oxytoca from the hands and environment. All of them were strong biofilm producers, but K. pneumoniae isolates produced more biofilm than K. oxytoca when compared to the American Type Culture Collection (ATCC) strains used as positive controls. The number of viable cells in the biofilm produced by K. pneumoniae isolated from blood was significantly higher than in the control sample. Regarding the three colorimetric tests used in the study, the violet crystal obtained a higher absorbance average. The use of crystal-violet and XTT in the evaluation of biofilm in vitro make possible a complete analysis, since that it can quantify the total biomass (including the extracellular matrix) and evaluate the metabolic activity. In conclusion, this study identified isolates of K. pneumoniae and K. oxytoca that produce biofilms in the NICU and the bloodstream of neonates. This fact deserves attention since these patients are immunocompromised. The best methods will be chosen to answer research questions by always adopting more than one method so that more than one parameter or component of the biofilm is analyzed.