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1.
Carbohydr Polym ; 332: 121915, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431395

RESUMO

This study aimed to explore an innovative approach to enhancing the shelf-life and quality of meat products through the application of an active packaging system. The study involved the development of new free-standing carboxymethyl cellulose (CMC) nanocomposite films incorporated with nanoencapsulated flavonoids derived from pomegranate extract. The loaded flavonoids, known for their antioxidant and antimicrobial properties, were nanoencapsulated via a self-assembly approach in a mixture of chitosan and sodium alginate to improve their stability, solubility, and controlled release characteristics. Chemical structure, size, and morphology of the obtained nanoparticles (Pg-NPs) were studied with FTIR, zeta-sizer, and TEM. The Pg-NPs showed particle size of 232 nm, and zeta-potential of -20.7 mV. Various free-standing nanocomposite films were then developed via incorporation of Pg-NPs into CMC-casted films. FTIR, SEM, thermal and mechanical properties, and surface wettability were intensively studied for the nanocomposite films. Barrier properties against water vapor were investigated at 2022 g·m-2d-1. The nanocomposite films possessed superior properties for inhibiting bacterial growth and extending the shelf-life of beef and poultry meat for 12 days compared with the Pg-NPs-free CMC films. This study presented a promising approach for development of active packaging systems with improved antimicrobial and antioxidant properties, and economic and environmental impacts.


Assuntos
Anti-Infecciosos , Punica granatum , Animais , Bovinos , Carboximetilcelulose Sódica/química , Embalagem de Alimentos , Antioxidantes/farmacologia , Antioxidantes/química , Carne/microbiologia , Anti-Infecciosos/farmacologia , Flavonoides
2.
Wiad Lek ; 77(1): 17-24, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38431802

RESUMO

OBJECTIVE: Aim: To investigate the epidemiology, microbiology, and risk factors for healthcare-associated infections (HAIs) after a neurosurgical procedure in Ukraine. PATIENTS AND METHODS: Materials and Methods: Prospective multicentre surveillance was conducted from January 2020 to December 2022 in 10 regional hospitals of Ukraine. Definitions of HAIs were adapted from the Centers for Disease Control and Prevention's National Healthcare Safety Network. RESULTS: Results: Of 8,623 neurosurgical patients, 1,579 (18.3%) HAIs were observed. The most frequently of HAI types were pneumonia (38.4%), surgical site infection (34.2%), urinary tract infection (18.1%) and bloodstream infection (9.3%). Death during hospitalization was reported in 11.3% of HAI cases. There was an association between HAIs after neurosurgical procedures and patients with diabetes mellitus, end-stage renal disease undergoing dialysis, and leukaemia. The strongest independent associations were observed for intubation, urinary catheters, and vascular catheters. Klebsiella pneumoniae were most commonly reported, accounting for 25.1% of all organisms, followed by Escherichia coli (17.6%), Staphylococcus aureus (9.9%), Pseudomonas aeruginosa (8.9%), Acinetobacter baumannii (8.5%), coagulase-negative staphylococci (6.8%), and Streptococcus spp. (5.5%). In total, 76.3% isolates from neurosurgical patients were MDROs. Antimicrobial resistance in Ukraine varies greatly by bacterial species, antimicrobial group, and region. CONCLUSION: Conclusions: Healthcare-associated infections are a cause for mortality and morbidity among neurosurgical patients. This is due to increase emergence of antimicrobial-resistant pathogens. Routinely collected surveillance data are of great value as a basis for studying the consequences of HAIs.


Assuntos
Anti-Infecciosos , Infecções Relacionadas a Cateter , Infecção Hospitalar , Infecções Urinárias , Humanos , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/microbiologia , Estudos Prospectivos , Ucrânia/epidemiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecções Urinárias/etiologia , Infecções Urinárias/microbiologia , Procedimentos Neurocirúrgicos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana
3.
Front Cell Infect Microbiol ; 14: 1346565, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469346

RESUMO

Stenotrophomonas maltophilia are ubiquitous Gram-negative bacteria found in both natural and clinical environments. It is a remarkably adaptable species capable of thriving in various environments, thanks to the plasticity of its genome and a diverse array of genes that encode a wide range of functions. Among these functions, one notable trait is its remarkable ability to resist various antimicrobial agents, primarily through mechanisms that regulate the diffusion across cell membranes. We have investigated the Mla ABC transport system of S. maltophilia, which in other Gram-negative bacteria is known to transport phospholipids across the periplasm and is involved in maintaining outer membrane homeostasis. First, we structurally and functionally characterized the periplasmic substrate-binding protein MlaC, which determines the specificity of this system. The predicted structure of the S. maltophilia MlaC protein revealed a hydrophobic cavity of sufficient size to accommodate the phospholipids commonly found in this species. Moreover, recombinant MlaC produced heterologously demonstrated the ability to bind phospholipids. Gene knockout experiments in S. maltophilia K279a revealed that the Mla system is involved in baseline resistance to antimicrobial and antibiofilm agents, especially those with divalent-cation chelating activity. Co-culture experiments with Pseudomonas aeruginosa also showed a significant contribution of this system to the cooperation between both species in the formation of polymicrobial biofilms. As suggested for other Gram-negative pathogenic microorganisms, this system emerges as an appealing target for potential combined antimicrobial therapies.


Assuntos
Anti-Infecciosos , Infecções por Bactérias Gram-Negativas , Stenotrophomonas maltophilia , Humanos , Stenotrophomonas maltophilia/metabolismo , Bactérias Gram-Negativas , Biofilmes , Membrana Celular , Anti-Infecciosos/metabolismo , Infecções por Bactérias Gram-Negativas/microbiologia
4.
Clin Lab ; 70(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38469762

RESUMO

BACKGROUND: The drug resistance of carbapenem-resistant Acinetobacter baumannii bloodstream infections (CRAB-BSI), especially hospital-acquired infections, has promoted their rapid and vast spread. It is necessary to use reliable methods to establish better prediction models. According to Cox proportional hazards regression, a nomogram was established. METHODS: A retrospective cohort study among patients who were diagnosed with CRAB-BSI was performed from January 2020 to December 2022. Univariate and multivariate Cox proportional hazards regression analyses were used to determine independent prognostic factors regarding CRAB-BSI. Then, nomograms were used to calculate the area under the curve (AUC), C-index, and calibration curve to determine the predictive accuracy and dis-criminability. Decision curve analysis (DCA) was employed to further confirm the clinical effectiveness of the nomogram. RESULTS: A total of 98 cases were included in the comparison between the 28-day mortality group consisting of 32 patients and the 28-day survival group with 66 patients. The use of cefoperazone-sulbactam was significantly higher among patients who survived than among those who died. Univariable analysis revealed that factors such as primary diagnosis, time to inadequate antimicrobial therapy, and high serum creatinine and procalcitonin (PCT) levels were more prevalent in the mortality group. However, only primary diagnosis, time to inadequate antimicrobial therapy, and high PCT levels emerged as statistically significant risk factors for death in multivariate analysis and were used to construct the nomogram. The nomogram validation exhibited excellent performance. CONCLUSIONS: The nomogram was sufficiently accurate to predict the risk and prognostic factors of CRAB-BSI, allowing for individualized clinical decisions for future clinical work. The cefoperazone-sulbactam did have an effect, but more studies are needed to interpret it.


Assuntos
Acinetobacter baumannii , Anti-Infecciosos , Sepse , Humanos , Nomogramas , Sulbactam/farmacologia , Cefoperazona/farmacologia , Cefoperazona/uso terapêutico , Estudos Retrospectivos , Anti-Infecciosos/farmacologia , Sepse/tratamento farmacológico , Prognóstico
5.
Eur Endod J ; 9(2): 154-160, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38456465

RESUMO

OBJECTIVE: Triple antibiotic paste (TAP) is known to have an essential role in the success of endodontic treatment by eliminating pathogens from the root canal system. Unfortunately, it causes discolouration and cytotoxicity at high concentrations. The objective of this research was to assess and compare the antimicrobial effectiveness of various concentrations (1 mg, 5 mg, 10 mg) of TAP, TAP hydrogel (TAPH), M-TAP, and M-TAP hydrogel (MTAPH) against Enterococcus faecalis. METHODS: The agar well diffusion method was used to assess the antibiotic sensitivity of the following intracanal medicaments: TAP (ciprofloxacin, metronidazole, and minocycline) mixed in a ratio of 1: 1: 1; TAPH, M-TAP (ciprofloxacin, metronidazole, and amoxicillin), M-TAPH and plain hydrogel. Each tested medicament was individually evaluated for its antimicrobial activity against Enterococcus faecalis. Structural and topographical characterisation were analysed using a Scanning Electron Microscope (SEM) and interpreted using ImageJ software. A microdilution broth test was performed to examine the minimum inhibitory concentration and minimum bactericidal concentration (MBC) of M-TAP and TAP. RESULTS: Except for the plain hydrogel, M-TAP and hydrogel and TAP and hydrogel showed significantly varied inhibitory zones at different concentrations. M-TAPH showed the highest mean zone of inhibition of 21.6, 33.33 and 38.0 mm at a concentration of 1, 5, and 10 mg/mL when compared to TAPH, which showed a mean zone of inhibition of 3.3 mm,12.3 mm, 21.3 mm at the respective concentrations. The MIC study shows that more than 75% of Enterococcus faecalis growth was inhibited by M-TAP at a concentration of 5 µg/mL, whereas TAP showed inhibition at a concentration of 35 µg/mL. MBC results indicate that almost 99.9% of the bacterial population was killed at a concentration of 100 µg/mL (10-1) for TAP and 10 µg/mL (10-2) for M-TAP. CONCLUSION: The antibacterial efficacy of M-TAP was significantly higher than TAP. Application of M-TAP at lower doses is advised to overcome the disadvantages seen with TAP.


Assuntos
Anti-Infecciosos , Hidrazonas , Metronidazol , Tiofenos , Metronidazol/farmacologia , Enterococcus faecalis , Hidrogéis/farmacologia , Antibacterianos/farmacologia , Ciprofloxacina , Bacitracina , Polimixina B , Framicetina
6.
BMC Pediatr ; 24(1): 177, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481225

RESUMO

The use of antimicrobials (AMs) in pediatric infections is common practice and use may be inappropriate leading to antimicrobial resistance. Off-label AM use is also common in this group and can result in drug-related problems. There is lack of DUR data in Brazil and in Latin America, specially for AM pediatric use. The aim of this study was to describe the utilization of AMs in hospitalized children in five hospitals in Brazil. We conducted an observational study of the utilization of AMs in pediatric wards in hospitals in the states of Ceará (CE), Sergipe (SE), Rio de Janeiro (RJ), Rio Grande do Sul (RS) and the Federal District (DF). Data derived from patient medical records and prescriptions were collected over a six-month period in each hospital. The number of AMs used by each patient was recorded, and AM use was assessed using Days of therapy (DOT) and Length of therapy (LOT) per 1000 patient days according to different patient characteristics. Off-label (OL) use was described according to age. The study analyzed data from 1020 patients. The sex and age distributions were similar across the five hospitals. However, differences were found for comorbidities, history of ICU admission and length of hospital stay. The most common diseases were respiratory tract infections. There were wide variations in DOT/1000PD (278-517) and LOT/1000PD (265-390). AM utilization was highest in the hospital in SE. The consumption of second-generation penicillins and cephalosporins was high. The prevalence of OL use of AMs was higher for patients in the RJ hospital, in infants, in patients who underwent prolonged hospital stays, and in patients who used multiple AMs. The AM that showed the highest prevalence of OL use was azithromycin, in both oral and parenteral formulations. Overall AM use was high and showed differences in each setting, possibly influenced by local characteristics and by prescribing standards adopted by pediatricians.


Assuntos
Anti-Infecciosos , Lactente , Criança , Humanos , Brasil , Hospitais , Hospitalização , Criança Hospitalizada , Antibacterianos/uso terapêutico , Hospitais Pediátricos
7.
BMC Urol ; 24(1): 60, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481245

RESUMO

BACKGROUND: To investigate the role of antimicrobial prophylaxis in laparoscopic nephrectomy for renal cell carcinoma. METHODS: We retrospectively enrolled 1000 patients who underwent laparoscopic nephrectomy from August 2019 to November 2021 in the Peking Union Medical College Hospital. Patients were divided into group without antimicrobial prophylaxis (n = 444) and group with antimicrobial prophylaxis (n = 556). Outcomes including 30-day postoperative infection rate, the increase rate of pre- and post-operative white blood cell counts and hospital stay were analyzed. RESULTS: The overall infection rate was 5.0% (28/556) in the group with antimicrobial prophylaxis, which was similar to 4.1% (18/444) in the group without antimicrobial prophylaxis (P = 0.461). The increase rate of pre- and post-operative white blood cell counts was significantly lower (85.5% versus 97.0%) in the group with antimicrobial prophylaxis (P = 0.004). The postoperative hospital stay was 5 (4, 6) days in both groups (P = 0.483). Logistic regression analyses identified the use of antimicrobial prophylaxis had no influence on the occurrence of infection events (odds ratio = 0.797; 95% confidence interval, 0.435-1.460; P = 0.462). Hemoglobin (odds ratio = 0.430; 95% confidence interval, 0.257-0.719; P = 0.001) and partial nephrectomy (odds ratio = 2.292; 95% confidence interval, 1.724-3.046; P < 0.001) influenced the use of antimicrobial prophylaxis independently. CONCLUSIONS: The use of antimicrobial prophylaxis had no impact on postoperative infection in patients receiving laparoscopic nephrectomy for renal cell carcinoma.


Assuntos
Anti-Infecciosos , Carcinoma de Células Renais , Neoplasias Renais , Laparoscopia , Humanos , Carcinoma de Células Renais/cirurgia , Carcinoma de Células Renais/patologia , Neoplasias Renais/cirurgia , Neoplasias Renais/patologia , Estudos Retrospectivos , Nefrectomia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/cirurgia , Resultado do Tratamento
8.
Wounds ; 36(2): 47-49, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38479431

RESUMO

OBJECTIVE: To conduct an in vitro investigation into the slough absorption and retention attributes of a gelling fiber dressing composed of CMC fibers and PHMB (Dressing A), and to assess its antimicrobial efficacy under compression. MATERIALS AND METHODS: Dressing A is indicated for use with secondary dressings or bandaging, and conditions that replicate this compression element were applied. Dressing A was compared with 5 other dressings. Antimicrobial efficacy testing was conducted over a 7-day challenge period. RESULTS: Dressing A absorbed an average of 33 g/100 cm2 per sample of viscous solution, 28% more than the other dressings tested. A greater than or equal to 6-log reduction of all microorganisms tested was achieved within 168 hours with Dressing A. CONCLUSION: The CMC PHMB gelling fiber dressing is able to absorb and retain viscous solutions (simulated slough). The antimicrobial efficacy of the dressing under compression was demonstrated by total eradication of all microorganisms tested.


Assuntos
Anti-Infecciosos , Humanos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Bandagens , Infecção da Ferida Cirúrgica , Pressão , Biguanidas
9.
Int J Mol Sci ; 25(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38473766

RESUMO

The aim of this work was to give as much information as possible on Rosa canina dried fruit that is commercially available in Serbia. In order to provide the chemical composition, the UHPLC-DAD-ESI-MS method was employed for both polar and non-polar extracts of samples obtained with a solvent mixture consisting of hexane, acetone, and ethanol in a volume ratio of 2:1:1, respectively, and 0.05% (w/v) butylated hydroxytoluene. In addition, the total content levels of lycopene, ß-carotene, total polyphenols, and flavonoids were determined by means of UV-vis spectrophotometry. The antioxidant activity was tested by applying four different methods: ABTS, DPPH, FRAP, and CUPRAC. Overall, nine compounds were identified. The results of chemical composition analysis were used as the basis for the interpretation of the calculated results for the antioxidant and antimicrobial activity. The obtained results for R. canina dried fruit extract are as follows: ß-carotene-7.25 [mg/100 g fruit weight]; lycopene-2.34 (mg/100 g FW); total polyphenol content (TPC)-2980 [mg GAE/kg FW]; total flavonoid content (TFC)-1454 [mg CE/kg FW]; antioxidant activity-ABTS 12.3 [µmol/100 g FW], DPPH 6.84, FRAP 52.04, and CUPRAC 15,425; and antimicrobial activity-Staphylococcus aureus MIC/MMC 4/0 [mg∙mL-1], Enterococcus faecalis 4/0, Bacillus cereus 4/0, Escherichia coli 4/0, Salmonella enteritidis 4/4, Enteroabacter aerogenes 4/0, Pseudomonas aeruginosa 2/0, and Candida albicans 2/0.


Assuntos
Anti-Infecciosos , Antioxidantes , Benzotiazóis , Ácidos Sulfônicos , Licopeno , Frutas , Sérvia , beta Caroteno , Escherichia coli , Flavonoides , Polifenóis , Extratos Vegetais
10.
Int J Mol Sci ; 25(5)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38473900

RESUMO

One of the key mechanisms enabling bacterial cells to create biofilms and regulate crucial life functions in a global and highly synchronized way is a bacterial communication system called quorum sensing (QS). QS is a bacterial cell-to-cell communication process that depends on the bacterial population density and is mediated by small signalling molecules called autoinducers (AIs). In bacteria, QS controls the biofilm formation through the global regulation of gene expression involved in the extracellular polymeric matrix (EPS) synthesis, virulence factor production, stress tolerance and metabolic adaptation. Forming biofilm is one of the crucial mechanisms of bacterial antimicrobial resistance (AMR). A common feature of human pathogens is the ability to form biofilm, which poses a serious medical issue due to their high susceptibility to traditional antibiotics. Because QS is associated with virulence and biofilm formation, there is a belief that inhibition of QS activity called quorum quenching (QQ) may provide alternative therapeutic methods for treating microbial infections. This review summarises recent progress in biofilm research, focusing on the mechanisms by which biofilms, especially those formed by pathogenic bacteria, become resistant to antibiotic treatment. Subsequently, a potential alternative approach to QS inhibition highlighting innovative non-antibiotic strategies to control AMR and biofilm formation of pathogenic bacteria has been discussed.


Assuntos
Anti-Infecciosos , Infecções Bacterianas , Humanos , Percepção de Quorum , Antibacterianos/farmacologia , Biofilmes , Bactérias , Anti-Infecciosos/farmacologia , Infecções Bacterianas/microbiologia
11.
Molecules ; 29(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38474448

RESUMO

Prosthetic infections are associated with high morbidity, mortality, and relapse rates, making them still a serious problem for implantology. Staphylococcus aureus is one of the most common bacterial pathogens causing prosthetic infections. In response to the increasing rate of bacterial resistance to commonly used antibiotics, this work proposes a method for combating pathogenic microorganisms by modifying the surfaces of synthetic polymeric biomaterials using proteolytic enzyme inhibitors (serine protease inhibitors-4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride and puromycin). While using techniques based on the immobilization of biologically active molecules, it is important to monitor the changes occurring on the surface of the modified biomaterial, where spectroscopic techniques (e.g., FTIR) are ideal. ATR-FTIR measurements demonstrated that the immobilization of both inhibitors caused large structural changes on the surface of the tested vascular prostheses (polyester or polytetrafluoroethylene) and showed that they were covalently bonded to the surfaces of the biomaterials. Next, the bactericidal and antibiofilm activities of the tested serine protease inhibitors were determined using the CLSM microscopic technique with fluorescent staining. During LIVE/DEAD analyses, a significant decrease in the formation of Staphylococcus aureus biofilm after exposure to selected concentrations of native inhibitors (0.02-0.06 mg/mL for puromycin and 0.2-1 mg/mL for 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride) was demonstrated.


Assuntos
Anti-Infecciosos , Infecções Estafilocócicas , Sulfonas , Humanos , Prótese Vascular , Antibacterianos/farmacologia , Biofilmes , Inibidores de Serino Proteinase/farmacologia , Staphylococcus aureus , Materiais Biocompatíveis , Puromicina , Peptídeo Hidrolases
12.
Molecules ; 29(5)2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38474510

RESUMO

The use of natural compounds to prevent and treat infective diseases is increasing its importance, especially in the case of multidrug-resistant (MDR) microorganisms-mediated infections. The drug resistance phenomenon is today a global problem, so it is important to have available substances able to counteract MDR infections. Syzygium aromaticum (L.) Merr. & L.M. Perry (commonly called clove) is a spice characterized by several biological properties. Clove essential oil (EO) consists of numerous active molecules, being eugenol as the principal component; however, other compounds that synergize with each other are responsible for the biological properties of the EO. S. aromaticum is traditionally used for bowel and stomach disorders, cold and flu, oral hygiene, tooth decay, and for its analgesic action. Its EO has shown antioxidant, antimicrobial, anti-inflammatory, neuro-protective, anti-stress, anticancer, and anti-nociceptive activities. This review aims to investigate the role of E. S. aromaticum EO in the counteraction of MDR microorganisms responsible for human disorders, diseases, or infections, such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhi, Candida albicans, Giardia lamblia, Streptococcus mutans, Porphyromonas gingivalis, and Klebsiella pneumoniae. This study might orient clinical researchers on future therapeutic uses of S. aromaticum EO in the prevention and treatment of infectious diseases.


Assuntos
Anti-Infecciosos , Óleos Voláteis , Syzygium , Humanos , Óleo de Cravo , Eugenol
13.
Molecules ; 29(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38474522

RESUMO

A biobased material, polythymol (PTF), was prepared using thymol, a monoterpene obtained from the essential oil of Thymus vulgaris (Lamiaceae), as a starting material with the aim of enhancing the antimicrobial properties of this natural product. Initially, different processes were performed in order to optimize the reaction conditions to obtain a macromolecule with a high purity and yield. PTF was characterized using different techniques, such as NMR, infrared, UV-Vis, and thermogravimetric analyses. The antimicrobial activity of both PTF and thymol was evaluated against different microorganisms, including S. aureus, E. coli, P. aeruginosa, and C. albicans. The obtained MIC values showed a higher potential for PTF than the monomer thymol-for example, against S. aureus (500 and 31.5 µg·mL-1 for thymol and PTF, respectively). Therefore, the obtained results show that the polymerization of thymol afforded more active biomaterial than the starting monomeric antimicrobial compound (thymol), suggesting that PTF is an important biomaterial.


Assuntos
Anti-Infecciosos , Óleos Voláteis , Timol/química , Staphylococcus aureus , Escherichia coli , Óleos Voláteis/química , Materiais Biocompatíveis , Testes de Sensibilidade Microbiana , Antibacterianos/química
14.
Molecules ; 29(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474580

RESUMO

Most diseases that affect human beings across the world are now treated with drugs of organic origin. However, some of these are associated with side effects, toxicity, and resistance phenomena. For the treatment of many illnesses, the development of new molecules with pharmacological potential is now an urgent matter. The biological activities of metal complexes have been reported to have antitumor, antimicrobial, anti-inflammatory, anti-infective and antiparasitic effects, amongst others. Metal complexes are effective because they possess unique properties. For example, the complex entity possesses the effective biological activity, then the formation of coordination bonds between the metal ions and ligands is controlled, metal ions provide it with extraordinary mechanisms of action because of characteristics such as d-orbitals, oxidation states, and specific orientations; metal complexes also exhibit good stability and good physicochemical properties such as water solubility. Platinum is a transition metal widely used in the design of drugs with antineoplastic activities; however, platinum is associated with side effects which have made it necessary to search for, and design, novel complexes based on other metals. Copper is a biometal which is found in living systems; it is now used in the design of metal complexes with biological activities that have demonstrated antitumoral, antimicrobial and anti-inflammatory effects, amongst others. In this review, we consider the open horizons of Cu(II)- and Pt(II)-based complexes, new trends in their design, their synthesis, their biological activities and their targets of action.


Assuntos
Anti-Infecciosos , Antineoplásicos , Complexos de Coordenação , Humanos , Cobre/química , Complexos de Coordenação/química , Platina/química , Antineoplásicos/farmacologia , Anti-Infecciosos/farmacologia , Íons , Anti-Inflamatórios , Ligantes
15.
Molecules ; 29(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474607

RESUMO

In the literature, the chemical composition of Rhododendron tomentosum is mainly represented by the study of isoprenoid compounds of essential oil. In contrast, the study of the content of flavonoids will contribute to the expansion of pharmacological action and the use of the medicinal plant for medical purposes. The paper deals with the technology of extracts from Rh. tomentosum shoots using ethanol of various concentrations and purified water as an extractant. Extracts from Rh. tomentosum were obtained by a modified method that combined the effects of ultrasound and temperature to maximize the extraction of biologically active substances from the raw material. Using the method of high-performance thin-layer chromatography in a system with solvents ethyl acetate/formic acid/water (15:1:1), the following substances have been separated and identified in all the extracts obtained: rutin, hyperoside, quercetin, and chlorogenic acid. The total polyphenol content (TPC) and total flavonoid content (TFC) were estimated using spectrophotometric methods involving the Folin-Ciocalteu (F-C) reagent and the complexation reaction with aluminum chloride, respectively. A correlation analysis was conducted between antioxidant activity and the polyphenolic substance content. Following the DPPH assay, regression analysis shows that phenolic compounds contribute to about 80% (r2 = 0.8028, p < 0.05) of radical scavenging properties in the extract of Rh. tomentosum. The extract of Rh. tomentosum obtained by ethanol 30% inhibits the growth of test cultures of microorganisms in 1:1 and 1:2 dilutions of the clinical strains #211 Staphylococcus aureus and #222 Enterococcus spp. and the reference strain Pseudomonas aeruginosa ATCC 10145.


Assuntos
Anti-Infecciosos , Rhododendron , Antioxidantes/química , Polifenóis , Flavonoides/farmacologia , Rhododendron/química , Extratos Vegetais/química , Anti-Infecciosos/análise , Etanol , Água
16.
Molecules ; 29(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38474690

RESUMO

Ardisia crenata Sims, an important ethnic medicine, is recorded in the Chinese Pharmacopoeia for treating laryngeal diseases and upper respiratory tract infections. This study aimed to evaluate the antimicrobial effect of extracts and potential antimicrobial compounds of A. crenata Sims. It was found that the roots of A. crenata Sims have a potential inhibitory effect on Candida albicans and Aspergillus flavus, with MICs of 1.56 mg/mL and 0.39 mg/mL, and the leaves of A. crenata Sims have a potential inhibitory effect on Pseudomonas aeruginosa and Staphylococcus aureus, with MICs of 3.12 mg/mL and 6.77 mg/mL, respectively. Meanwhile, five compounds including one catechin and four bergenins were obtained from roots. These components were identified on the fingerprint spectrum, representing chromatographic peaks 16, 21, 22, 23, and 25, respectively. Among these, 11-ß-d-glucopyranosyl-bergenin and (-)-gallocatechin showed potential inhibition for Staphylococcus aureus and Pseudomonas aeruginosa with MIC of 0.26 and 0.33 mg/mL, respectively. The roots, stems, and leaves of A. crenata Sims are very similar in chemical composition, with large differences in content. Principal component analysis (PCA) and Hierarchical cluster analysis (HCA) showed that 16 batches of A. crenata Sims could be divided into four main production areas: Guizhou, Jiangsu, Guangxi, and Jiangxi. Furthermore, molecular docking results showed that 11-ß-d-glucopyranosyl-bergenin had a better affinity for Casein lytic proteinase P (ClpP), and (-)-gallocatechin possessed a strong affinity for LasA hydrolysis protease and LasB elastase. These findings suggest catechin and bergenins from A. crenata Sims can be used as antimicrobial activity molecules.


Assuntos
Anti-Infecciosos , Ardisia , Catequina , Cromatografia Líquida de Alta Pressão , Simulação de Acoplamento Molecular , China
17.
Molecules ; 29(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38474693

RESUMO

Antimicrobial peptides (AMPs), acknowledged as host defense peptides, constitute a category of predominant cationic peptides prevalent in diverse life forms. This study explored the antibacterial activity of α-conotoxin RgIA, and to enhance its stability and efficacy, D-amino acid substitution was employed, resulting in the synthesis of nine RgIA mutant analogs. Results revealed that several modified RgIA mutants displayed inhibitory efficacy against various pathogenic bacteria and fungi, including Candida tropicalis and Escherichia coli. Mechanistic investigations elucidated that these polypeptides achieved antibacterial effects through the disruption of bacterial cell membranes. The study further assessed the designed peptides' hemolytic activity, cytotoxicity, and safety. Mutants with antibacterial activity exhibited lower hemolytic activity and cytotoxicity, with Pep 8 demonstrating favorable safety in mice. RgIA mutants incorporating D-amino acids exhibited notable stability and adaptability, sustaining antibacterial properties across diverse environmental conditions. This research underscores the potential of the peptide to advance innovative oral antibiotics, offering a novel approach to address bacterial infections.


Assuntos
Anti-Infecciosos , Conotoxinas , Camundongos , Animais , Lisina/farmacologia , Leucina/farmacologia , Substituição de Aminoácidos , Conotoxinas/química , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias , Testes de Sensibilidade Microbiana
18.
Bioorg Chem ; 145: 107239, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428282

RESUMO

Antimicrobial resistance (AMR) is a serious global concern and a huge burden on the healthcare system. Antimicrobial peptides (AMPs) are considered as a solution of AMR due to their membrane-lytic and intracellular mode of action and therefore resistance development against AMPs is less frequent. One such AMPs, temporin-L (TL) is a 13-mer peptide reported as a potent and broad-spectrum antibacterial agent with significant immunomodulatory activity. However, TL is toxic to human erythrocytes at their antibacterial concentrations and therefore various analogues were synthesized with potent antimicrobial activity and lower hemolytic activity. In this work, we have selected a non-toxic engineered analogue of TL (eTL) and performed hydrocarbon stapling of amino acid residues at i to i + 4 positions at different part of sequence. The synthesized peptides were investigated against both the gram-positive and gram-negative bacteria as well as methicillin resistant S. aureus, its MIC was measured in the concentrations range of 0.9-15.2 µM. All analogues were found equal or better antibacterial as compared to parent peptide. Interestingly one analogue eTL [5-9] was found to be non-cytotoxic and stable in presence of the human serum. Mode of action studies revealed membrane depolarizing and disruptive mode of action with live MRSA. Further in vivo studies of antimicrobial against MRSA infection and anti-endotoxin activities in mice model revealed potential activity of the stapled peptide analogue. Overall, this reports on stapled analogue of the AMPs highlights an important strategy for the development of new antibacterial therapeutics against AMR.


Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Animais , Camundongos , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Peptídeo Hidrolases , Bactérias Gram-Positivas , Bactérias Gram-Negativas , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Anti-Infecciosos/farmacologia , Endopeptidases , Hidrocarbonetos , Testes de Sensibilidade Microbiana
19.
Bioorg Chem ; 145: 107252, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38437763

RESUMO

Isoquinoline alkaloids are an important class of natural products that are abundant in the plant kingdom and exhibit a wide range of structural diversity and biological activities. With the deepening of research in recent years, more and more isoquinoline alkaloids have been isolated and identified and proved to contain a variety of biological activities and pharmacological effects. In this review, we introduce the research progress of isoquinoline alkaloids from 2019 to 2022, mainly in the part of biological activities, including antitumor, antimicrobial, antidiabetic, antiviral, anti-inflammatory, antioxidant, neuroprotective, hepatoprotective, analgesic, and other activities. This study provides a clear direction for the rational development and utilization of isoquinoline alkaloids, suggesting that these alkaloids have great potential in the field of drug research.


Assuntos
Alcaloides , Anti-Infecciosos , Alcaloides/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Isoquinolinas/farmacologia , Isoquinolinas/química
20.
Arch Microbiol ; 206(4): 142, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441673

RESUMO

The objective of the current study was to examine the antimicrobial, anti-adhesion, and anti-invasion properties of various concentrations of condition media obtained from adipose mesenchymal stem cells (AD-MSCs CM) against Shigella flexneri (S. flexneri). AD-MSCs characterization and antimicrobial assay were performed using flow cytometry and microdilution by colony counting, respectively. For evaluating adhesion and invasion, Caco-2 cells were infected by S. flexneri at three different multiplicities of infection (MOIs of 1, 10, and 50) and then treated with DMEM medium and AD-MSCs CM. The inhibitory effect of AD-MSCs CM was assessed after 24 and 48 h of treatment by CFU (colony-forming unit) counting. A total of 84, 65, and 56% reduction in the adhesion rate of S. flexneri to Caco-2 cells treated with AD-MSCs CM were observed at MOIs of 1, 10, and 50, respectively. While S. flexneri at MOI:1 had no invasive effect on Caco-2 cells, convincing invasion was detected at MOIs of 10 and 50, showing a significant decrease following treatment with AD-MSCs CM. The current study results open new insights into AD-MSCs CM as a new non-antibiotic therapeutic candidate for S. flexneri infections.


Assuntos
Anti-Infecciosos , Células-Tronco Mesenquimais , Humanos , Shigella flexneri , Células CACO-2 , Obesidade
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