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1.
Biochem Biophys Res Commun ; 714: 149974, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38663094

RESUMEN

Due to the rapid emergence of antibiotic resistant new bacterial strains and new infections, there is an urgent need for novel or newly modified and efficient alternatives of treatment. However, conventional antibiotics are still used in therapeutic settings but their efficacy is uncertain due to the rapid evolution of drug resistance. In the present study, we have synthesized a new derivative of conventional antibiotic ampicillin using SN2-type substitution reaction. NMR and mass analysis of the newly synthesized derivative of ampicillin confirmed it as ampicillin-bromo-methoxy-tetralone (ABMT). Importantly, ABMT is revealed to have efficient activity against Staphylococcus aureus (S. aureus) with a MIC value of 32 µg ml-1 while ampicillin was not effective, even at 64 µg ml-1 of concentration. Electron microscopy results confirmed the membrane-specific killing of S. aureus at 1 h of treatment. Additionally, molecular docking analysis revealed a strong binding affinity of ABMT with ß-lactamase via the formation of a closed compact bridge. Our findings, avail a new derivative of ampicillin that could be a potential alternative to fight ampicillin-resistant bacteria possibly by neutralizing the ß-lactamase action.


Asunto(s)
Ampicilina , Antibacterianos , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Staphylococcus aureus , Ampicilina/farmacología , Antibacterianos/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Tetralonas/farmacología , Tetralonas/química , Tetralonas/síntesis química , Resistencia a la Ampicilina , beta-Lactamasas/metabolismo
2.
Biochem Biophys Res Commun ; 734: 150622, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39216410

RESUMEN

Administration of coronavirus disease-2019 (COVID-19) vaccines with appropriate booster doses through painful injections under clinical supervision was challenging during the recent COVID-19 pandemic. As an alternative solution, we designed a safer, edible probiotic yogurt vaccine prototype (YoVac) that can be orally consumed by circumventing painful injections and clinical supervision. We hypothesized that YoVac prepared using Lactobacillus carrying an antigen coding gene (donor) can transfer the same to other bacteria (recipients) in the human gut microbiome (hgMb) through lateral gene transfer (LGT) for boosted antigen levels potentially triggering a robust immune response. In this study we confirmed the in vitro LGT efficiency of a plasmid (pRBD-Ampr) containing severe acute respiratory syndrome coronavirus-2 (SARS CoV-2) spike protein-receptor binding domain (RBD) coding gene along with an ampicillin-resistance gene (selection marker) from the probiotic Lactobacillus (donor) cultured from homemade yogurt to E. coli and Helicobacter pylori (recipients). Both the donor and recipient bacteria not only exhibited ampicillin-resistance from pRBD-Ampr but also expressed RBD protein. Furthermore, Lactobacillus isolated from YoVac consistently showed the expression of RBD protein over a period of one month confirming the shelf life of our prototype stored at 4 °C. Taken together, our in vitro results provide a preliminary basis for the potential in vivo transfer of RBD coding gene from YoVac to other bacterial species in the hgMb through LGT and may potentially boost the vaccine dosage by delegating them.

3.
J Mol Recognit ; 37(5): e3100, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39014869

RESUMEN

Metallo-ß-lactamases (MßLs) hydrolyze and inactivate ß-lactam antibiotics, are a pivotal mechanism conferring resistance against bacterial infections. SMB-1, a novel B3 subclass of MßLs from Serratia marcescens could deactivate almost all ß-lactam antibiotics including ampicillin (AMP), which has posed a serious threat to public health. To illuminate the mechanism of recognition and interaction between SMB-1 and AMP, various fluorescence spectroscopy techniques and molecular dynamics simulation were employed. The results of quenching spectroscopy unraveled that AMP could make SMB-1 fluorescence quenching that mechanism was the static quenching; the synchronous and three-dimensional fluorescence spectra validated that the microenvironment and conformation of SMB-1 were altered after interaction with AMP. The molecular dynamics results demonstrated that the whole AMP enters the binding pocket of SMB-1, even though with a relatively bulky R1 side chain. Loop1 and loop2 in SMB-1 undergo significant fluctuations, and α2 (71-73) and local α5 (186-188) were turned into random coils, promoting zinc ion exposure consistent with circular dichroism spectroscopy results. The binding between them was driven by a combination of enthalpy and entropy changes, which was dominated by electrostatic force in agreement with the fluorescence observations. The present study brings structural insights and solid foundations for the design of new substrates for ß-lactamases and the development of effective antibiotics that are resistant to superbugs.


Asunto(s)
Ampicilina , Simulación de Dinámica Molecular , Serratia marcescens , Espectrometría de Fluorescencia , beta-Lactamasas , beta-Lactamasas/química , beta-Lactamasas/metabolismo , Ampicilina/química , Ampicilina/metabolismo , Ampicilina/farmacología , Serratia marcescens/enzimología , Unión Proteica , Sitios de Unión , Antibacterianos/química , Antibacterianos/farmacología , Antibacterianos/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo
4.
Int J Med Microbiol ; 316: 151626, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38954914

RESUMEN

BACKGROUND: Aminopenicillins are recommended agents for non-invasive Haemophilus influenzae infections. One of the mechanisms of resistance to ß-lactams is the alteration of the transpeptidase region of penicillin binding protein 3 (PBP3) which is caused by mutations in the ftsI gene. It was shown that exposure to beta-lactams has a stimulating effect on increase of prevalence of H. influenzae strains with the non-enzymatic mechanism of resistance. OBJECTIVES: The aim of our study was to compare the mutational potential of ampicillin and cefuroxime in H. influenzae strains, determination of minimum inhibitory concentration and the evolution of mutations over time, focusing on amino acid substitutions in PBP3. METHODS: 30 days of serial passaging of strains in liquid broth containing increasing concentrations of ampicillin or cefuroxime was followed by whole-genome sequencing. RESULTS: On average, cefuroxime increased the minimum inhibitory concentration more than ampicillin. The minimum inhibitory concentration was increased by a maximum of 32 fold. Substitutions in the PBP3 started to appear after 15 days of passaging. In PBP3, cefuroxime caused different substitutions than ampicillin. CONCLUSIONS: Our experiment observed differences in mutation selection by ampicillin and cefuroxime. Selection pressure of antibiotics in vitro generated substitutions that do not occur in clinical strains in the Czech Republic.


Asunto(s)
Sustitución de Aminoácidos , Ampicilina , Antibacterianos , Cefuroxima , Haemophilus influenzae , Pruebas de Sensibilidad Microbiana , Mutación , Proteínas de Unión a las Penicilinas , Cefuroxima/farmacología , Ampicilina/farmacología , Haemophilus influenzae/genética , Haemophilus influenzae/efectos de los fármacos , Proteínas de Unión a las Penicilinas/genética , Proteínas de Unión a las Penicilinas/metabolismo , Antibacterianos/farmacología , Humanos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Infecciones por Haemophilus/microbiología , Secuenciación Completa del Genoma , Evolución Molecular , Selección Genética , Pase Seriado
5.
Anal Biochem ; 687: 115459, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38182031

RESUMEN

The combination of nanomaterials possessing distinct characteristics and the precision of aptamers facilitates the creation of biosensors that exhibit exceptional selectivity and sensitivity. In this manuscript, we present a highly sensitive aptasensor that utilizes the distinctive characteristics of MnO2 nanoflowers and gold nanoparticles to selectively detect ampicillin (AMP). In this aptasensor, the mechanism of signal change is attributed to the difference in the oxidase-mimicking activity of MnO2 nanoflowers in the presence of a free sequence. The inclusion of AMP hindered the creation of a double-stranded DNA configuration through its binding to the aptamer, resulting in an observable alteration in absorbance. The relative absorbance varied linearly with the concentration of AMP in the range of 70 pM to 10 nM with a detection limit of 21.7 pM. In general, the colorimetric aptasensor that has been developed exhibits exceptional selectivity and remarkable stability. It also demonstrates favorable performance in human serum, making it a highly reliable diagnostic tool. Additionally, its versatility is noteworthy as it holds great potential for detecting various antibiotics present in complex samples by merely replacing the utilized sequences with new ones.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Nanopartículas del Metal , Humanos , Oro , Límite de Detección , Colorimetría/métodos , Compuestos de Manganeso , Óxidos , Técnicas Biosensibles/métodos , Ampicilina
6.
Am J Obstet Gynecol ; 230(3S): S807-S840, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38233317

RESUMEN

Clinical chorioamnionitis, the most common infection-related diagnosis in labor and delivery units, is an antecedent of puerperal infection and neonatal sepsis. The condition is suspected when intrapartum fever is associated with two other maternal and fetal signs of local or systemic inflammation (eg, maternal tachycardia, uterine tenderness, maternal leukocytosis, malodorous vaginal discharge or amniotic fluid, and fetal tachycardia). Clinical chorioamnionitis is a syndrome caused by intraamniotic infection, sterile intraamniotic inflammation (inflammation without bacteria), or systemic maternal inflammation induced by epidural analgesia. In cases of uncertainty, a definitive diagnosis can be made by analyzing amniotic fluid with methods to detect bacteria (Gram stain, culture, or microbial nucleic acid) and inflammation (white blood cell count, glucose concentration, interleukin-6, interleukin-8, matrix metalloproteinase-8). The most common microorganisms are Ureaplasma species, and polymicrobial infections occur in 70% of cases. The fetal attack rate is low, and the rate of positive neonatal blood cultures ranges between 0.2% and 4%. Intrapartum antibiotic administration is the standard treatment to reduce neonatal sepsis. Treatment with ampicillin and gentamicin have been recommended by professional societies, although other antibiotic regimens, eg, cephalosporins, have been used. Given the importance of Ureaplasma species as a cause of intraamniotic infection, consideration needs to be given to the administration of antimicrobial agents effective against these microorganisms such as azithromycin or clarithromycin. We have used the combination of ceftriaxone, clarithromycin, and metronidazole, which has been shown to eradicate intraamniotic infection with microbiologic studies. Routine testing of neonates born to affected mothers for genital mycoplasmas could improve the detection of neonatal sepsis. Clinical chorioamnionitis is associated with decreased uterine activity, failure to progress in labor, and postpartum hemorrhage; however, clinical chorioamnionitis by itself is not an indication for cesarean delivery. Oxytocin is often administered for labor augmentation, and it is prudent to have uterotonic agents at hand to manage postpartum hemorrhage. Infants born to mothers with clinical chorioamnionitis near term are at risk for early-onset neonatal sepsis and for long-term disability such as cerebral palsy. A frontier is the noninvasive assessment of amniotic fluid to diagnose intraamniotic inflammation with a transcervical amniotic fluid collector and a rapid bedside test for IL-8 for patients with ruptured membranes. This approach promises to improve diagnostic accuracy and to provide a basis for antimicrobial administration.


Asunto(s)
Corioamnionitis , Sepsis Neonatal , Hemorragia Posparto , Femenino , Recién Nacido , Embarazo , Humanos , Corioamnionitis/diagnóstico , Corioamnionitis/tratamiento farmacológico , Corioamnionitis/etiología , Claritromicina/uso terapéutico , Hemorragia Posparto/tratamiento farmacológico , Sepsis Neonatal/diagnóstico , Sepsis Neonatal/tratamiento farmacológico , Antibacterianos/uso terapéutico , Líquido Amniótico/microbiología , Inflamación/metabolismo , Taquicardia
7.
Int Microbiol ; 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38502456

RESUMEN

Antibiotics are commonly used to treat infectious diseases; however, persistence is often expressed by the pathogenic bacteria and their long-term relative effect on the host have been neglected. The present study investigated the impact of antibiotics in gut microbiota (GM) and metabolism of host. The effect of ampicillin antibiotics on GM of Drosophila melanogaster was analyzed through deep sequencing of 16S rRNA amplicon gene. The dominant phyla consisted of Proteobacteria, Bacteroidetes, Firmicutes, Actinobacteria, Planctomycetes, Chloroflexi, Euryarchaeota, Acedobacteria, Verrucomicrobia, and Cyanobacteria. It was found that the composition of GM was significantly altered on administration of antibiotics. On antibiotic treatments, there were decline in relative abundance of Proteobacteria and Firmicutes, while there were increase in relative abundance of Chlorophyta and Bacteroidota. High abundance of 14 genera, viz., Wolbachia, Lactobacillus, Bacillus, Pseudomonas, Thiolamprovum, Pseudoalteromonas, Vibrio, Romboutsia, Staphylococcus, Alteromonas, Clostridium, Lysinibacillus, Litoricola, and Cellulophaga were significant (p ≤ 0.05) upon antibiotic treatment. Particularly, the abundance of Acetobacter was significantly (p ≤ 0.05) declined but increased for Wolbachia. Further, a significant (p ≤ 0.05) increase in Wolbachia endosymbiont of D. melanogaster, Wolbachia endosymbiont of Curculio okumai, and Wolbachia pipientis and a decrease in the Acinetobacter sp. were observed. We observed an increase in functional capacity for biosynthesis of certain nucleotides and the enzyme activities. Further, the decrease in antimicrobial peptide production in the treated group and potential effects on the host's defense mechanisms were observed. This study helps shed light on an often-overlooked dimension, namely the persistence of antibiotics' effects on the host.

8.
Eur J Clin Microbiol Infect Dis ; 43(9): 1711-1719, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38970691

RESUMEN

To evaluate the in vitro activity of ampicillin-sulbactam and cefoperazone-sulbactam against A. baumannii using the broth disk elution testing, a total of 150 A. baumannii isolates were collected from across China between January 2019 and January 2021, including 51 carbapenem-susceptible and 99 carbapenem-resistant isolates. Broth disk elution (BDE) and the broth microdilution (BMD) method were performed for all strains. The concentration range of the BDE was 10/10 µg/mL, 20/20 µg/mL, and 30/30 µg/mL for ampicillin-sulbactam, and 37.5/15 µg/mL, 75/30 µg/mL, 112.5/45 µg/mL, and 150/60 µg/mL for cefoperazone-sulbactam, respectively. Compared with BMD, the BDE results of ampicillin-sulbactam and cefoperazone-sulbactam showed a categorical agreement of 83.3% (125/150) and 95.3% (143/150), with minor errors of 16.7% (25/150) and 4.7% (7/150), respectively. No major error or very major errors were detected. The sensitivity differences by BDE of carbapenem-resistant A. baumannii (CRAb) to different concentrations of ampicillin-sulbactam showed statistically significant (p < 0.017), while those to cefoperazone-sulbactam at 37.5/15 µg/mL, 75/30 µg/mL, and 112.5/45 µg/mL were significant (p < 0.008). However, no significant difference in sensitivity was observed between 112.5/45 µg/mL and 150/60 µg/mL (p > 0.008). In conclusion, the BDE is a reliable and convenient method to detect the in vitro activity of cefoperazone-sulbactam against A. baumannii, and the results could serve as a clinical reference value when deciding whether or not to use high-dose sulbactam for the treatment of A. baumannii infections.


Asunto(s)
Acinetobacter baumannii , Ampicilina , Antibacterianos , Cefoperazona , Sulbactam , Acinetobacter baumannii/efectos de los fármacos , Sulbactam/farmacología , Cefoperazona/farmacología , Ampicilina/farmacología , Antibacterianos/farmacología , Humanos , Infecciones por Acinetobacter/microbiología , Pruebas de Sensibilidad Microbiana , China , Pruebas Antimicrobianas de Difusión por Disco/métodos
9.
Eur J Clin Microbiol Infect Dis ; 43(7): 1453-1459, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38676856

RESUMEN

We present our findings on interpatient transmission, epidemic control measures, and the outcomes of a series of ten critically ill burn patients who were either colonized or infected with carbapenem-resistant Acinetobacter baumannii (CRAB). None of the five infected patients achieved clinical cure, and all experienced relapses. Microbiological failure was observed in 40% of the infected patients. The isolated CRAB strains were found to carry blaOXA-23 and armA resistance genes. Despite the lack of clinical cure, all five infected patients survived and were discharged from the Burn Intensive Care Unit.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Antibacterianos , Compuestos de Azabiciclo , Carbapenémicos , Ceftazidima , Brotes de Enfermedades , Combinación de Medicamentos , Unidades de Cuidados Intensivos , Sulbactam , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/genética , Acinetobacter baumannii/aislamiento & purificación , Humanos , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/microbiología , Infecciones por Acinetobacter/epidemiología , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Masculino , Compuestos de Azabiciclo/uso terapéutico , Compuestos de Azabiciclo/farmacología , Sulbactam/uso terapéutico , Sulbactam/farmacología , Femenino , Persona de Mediana Edad , Adulto , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Ceftazidima/uso terapéutico , Ceftazidima/farmacología , Quemaduras/complicaciones , Quemaduras/microbiología , Quimioterapia Combinada , Resultado del Tratamiento , Anciano , Infección Hospitalaria/microbiología , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Farmacorresistencia Bacteriana Múltiple/genética , beta-Lactamasas/genética , Unidades de Quemados
10.
J Fluoresc ; 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38457076

RESUMEN

Herein, a fluorescent "on-off-on" nanosensor based on N,S-CDs was developed for highly precise and sensitive recognition of Hg2+ and ampicillin (AMP). Nitrogen and sulfur co-doped carbon dots with blue fluorescence were synthesized by one-pot hydrothermal method using ammonium citrate and DL-methionine as precursors. N,S-CDs exhibited a surface abundant in -OH, -COOH, and -NH2 groups, aiding in creating non-fluorescent ground state complexes when combined with Hg2+, leading to the suppression of N,S-CDs' fluorescence. Subsequent to additional AMP application, the mixed system's fluorescence was restored. Based on this N,S-CDs sensing system, the thresholds for detection for AMP and Hg2+ were discovered to be 0.121 µM and 0.493 µM, respectively. Furthermore, this methodology proved effective in identifying AMP in real samples of tap and lake water, yielding satisfactory results. Consequently, in the area of bioanalysis in intricate environmental sample work, the sensing system showed tremendous promise.

11.
Appl Microbiol Biotechnol ; 108(1): 5, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38165477

RESUMEN

Antibiotic resistance is an important problem that threatens medical treatment. Differences in the resistance levels of microorganisms cause great difficulties in understanding the mechanisms of antibiotic resistance. Therefore, the molecular reasons underlying the differences in the level of antibiotic resistance need to be clarified. For this purpose, genomic and transcriptomic analyses were performed on three Escherichia coli strains with varying degrees of adaptive resistance to ampicillin. Whole-genome sequencing of strains with different levels of resistance detected five mutations in strains with 10-fold resistance and two additional mutations in strains with 95-fold resistance. Overall, three of the seven mutations occurred as a single base change, while the other four occurred as insertions or deletions. While it was thought that 10-fold resistance was achieved by the effect of mutations in the ftsI, marAR, and rpoC genes, it was found that 95-fold resistance was achieved by the synergistic effect of five mutations and the ampC mutation. In addition, when the general transcriptomic profiles were examined, it was found that similar transcriptomic responses were elicited in strains with different levels of resistance. This study will improve our view of resistance mechanisms in bacteria with different levels of resistance and provide the basis for our understanding of the molecular mechanism of antibiotic resistance in ampicillin-resistant E. coli strains. KEY POINTS: •The mutation of the ampC promoter may act synergistically with other mutations and lead to higher resistance. •Similar transcriptomic responses to ampicillin are induced in strains with different levels of resistance. •Low antibiotic concentrations are the steps that allow rapid achievement of high antibiotic resistance.


Asunto(s)
Resistencia a la Ampicilina , Escherichia coli , Resistencia a la Ampicilina/genética , Escherichia coli/genética , Ampicilina/farmacología , Antibacterianos/farmacología , Perfilación de la Expresión Génica
12.
Appl Microbiol Biotechnol ; 108(1): 172, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38265501

RESUMEN

The resistance of biofilms to antibiotics is a key factor that makes bacterial infections unsusceptible to antimicrobial therapy. The results of classical tests of cell sensitivity to antibiotics cannot be used to predict therapeutic success in infections associated with biofilm formation. We describe a simple and rapid method for the real-time evaluation of bacterial biofilm sensitivity to antibiotics, with Pseudomonas putida and ampicillin as examples. The method uses an electric biosensor to detect the difference between changes in the biofilm electric polarizability, thereby evaluating antibiotic sensitivity. The electric signals showed that P. putida biofilms were susceptible to ampicillin and that at high antibiotic concentrations, the biofilms differed markedly in their susceptibility (dose-dependent effect). The sensor also detected differences between biofilms before and after ampicillin treatment. The electric-signal changes enabled us to describe the physical picture of the processes occurring in bacterial biofilms in the presence of ampicillin. The approach used in this study is promising for evaluating the activity of various compounds against biofilms, because it permits a conclusion about the antibiotic sensitivity of biofilm bacteria to be made in real time and in a short period (analysis time, not longer than 20 min). An added strong point is that analysis can be done directly in liquid, without preliminary sample preparation. KEY POINTS: • Sensor system to analyze biofilm antimicrobial susceptibility is described. • The signal change depended on the ampicillin concentration (dose-dependent effect). • The sensor allows real-time determination of the antibiofilm effect of ampicillin.


Asunto(s)
Ampicilina , Pseudomonas putida , Antibacterianos , Biopelículas , Electricidad
13.
J Infect Chemother ; 30(7): 655-658, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38141719

RESUMEN

Corynebacterium striatum occasionally causes nosocomial infections, such as catheter-related bloodstream infection and pneumonia; however, C. striatum-related infective endocarditis or septic arthritis is uncommon. We present the case of an 85-year-old woman with infective endocarditis at the native valve and septic arthritis at the native shoulder joint caused by C. striatum. The patient was admitted for a 10-day history of fever and right shoulder pain. She had no history of artificial device implantation, injury, arthrocentesis, or hospitalization. A physical examination revealed conjunctival petechiae, a systolic heart murmur, and right shoulder joint swelling. C. striatum was observed in two blood culture sets. Transesophageal echocardiography revealed vegetation in the right aortic coronary cusp. Arthrocentesis at the right shoulder aspirated pyogenic fluid and C. striatum was detected in the culture. The patient was diagnosed with infective endocarditis and septic arthritis caused by C. striatum, and ampicillin was administered based on antimicrobial susceptibility test results. The patient's condition was initially stable; however, she developed pulmonary congestion on day 56 and eventually died. An autopsy demonstrated perforation of the aortic left coronary cusp with vegetation. C. striatum may cause native valve endocarditis and native joint septic arthritis.


Asunto(s)
Artritis Infecciosa , Infecciones por Corynebacterium , Corynebacterium , Endocarditis Bacteriana , Humanos , Femenino , Artritis Infecciosa/microbiología , Artritis Infecciosa/diagnóstico , Artritis Infecciosa/tratamiento farmacológico , Corynebacterium/aislamiento & purificación , Anciano de 80 o más Años , Infecciones por Corynebacterium/microbiología , Infecciones por Corynebacterium/diagnóstico , Infecciones por Corynebacterium/tratamiento farmacológico , Infecciones por Corynebacterium/complicaciones , Endocarditis Bacteriana/microbiología , Endocarditis Bacteriana/diagnóstico , Endocarditis Bacteriana/tratamiento farmacológico , Endocarditis Bacteriana/complicaciones , Resultado Fatal , Antibacterianos/uso terapéutico , Ecocardiografía Transesofágica , Válvula Aórtica/microbiología , Válvula Aórtica/patología , Válvula Aórtica/diagnóstico por imagen
14.
Acta Paediatr ; 113(7): 1694-1700, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38578153

RESUMEN

AIM: To compare the prophylactic efficacy of ampicillin and clindamycin against vertical transmission of group B Streptococcus from mothers to their infants by evaluating the rates of group B Streptococcus colonisation. METHODS: We retrospectively extracted data for mothers who delivered at Showa University Northern Yokohama Hospital between 1 October 2017 and 31 March 2021 and tested positive for antepartum group B Streptococcus, and their infants. The chi-square test was used to compare the rates of group B Streptococcus colonisation, sepsis, and meningitis. We conducted a multivariate logistic regression analysis, including the time interval between membrane rupture and delivery, chorioamnionitis, and maternal intrapartum fever (≥38.0°C). RESULTS: Two hundred fifty-nine mothers and their infants were eligible. Ampicillin and clindamycin were administered to 150 and 109 mothers, respectively. In the ampicillin and clindamycin groups, 12.0% (18/150) and 37.6% (41/109) infants were group B Streptococcus positive, respectively. The rate of group B Streptococcus colonisation among infants was significantly lower in the ampicillin group (p < 0.001). Multivariate regression analysis showed similar results (p < 0.001). No sepsis or meningitis cases were observed in either group. CONCLUSION: Prophylactic efficacy of clindamycin against the vertical transmission of group B Streptococcus is lower than that of ampicillin.


Asunto(s)
Ampicilina , Antibacterianos , Clindamicina , Transmisión Vertical de Enfermedad Infecciosa , Infecciones Estreptocócicas , Streptococcus agalactiae , Humanos , Ampicilina/uso terapéutico , Clindamicina/uso terapéutico , Femenino , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Estudios Retrospectivos , Infecciones Estreptocócicas/prevención & control , Infecciones Estreptocócicas/transmisión , Embarazo , Antibacterianos/uso terapéutico , Recién Nacido , Adulto , Profilaxis Antibiótica/métodos , Complicaciones Infecciosas del Embarazo/prevención & control , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico
15.
Mikrochim Acta ; 191(5): 294, 2024 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698253

RESUMEN

Early transition metal carbides (MXene) hybridized by precious metals open a door for innovative electrochemical biosensing device design. Herein, we present a facile one-pot synthesis of gold nanoparticles (AuNPs)-doped two-dimensional (2D) titanium carbide MXene nanoflakes (Ti3C2Tx/Au). Ti3C2Tx MXene exhibits high electrical conductivity and yields synergistic signal amplification in conjunction with AuNPs leading to excellent electrochemical performance. Thus Ti3C2Tx/Au hybrid nanostructure can be used as an electrode platform for the electrochemical analysis of various targets. We used screen-printed electrodes modified with the Ti3C2Tx/Au electrode and functionalized with different biorecognition elements to detect and quantify an antibiotic, ampicillin (AMP), and a mycotoxin, fumonisin B1 (FB1). The ultralow limits of detection of 2.284 pM and 1.617 pg.mL-1, which we achieved respectively for AMP and FB1 are far lower than their corresponding maximum residue limits of 2.8 nM in milk and 2 to 4 mg kg-1 in corn products for human consumption set by the United States Food and Drug Administration. Additionally, the linear range of detection and quantification of AMP and FB1 were, respectively, 10 pM to 500 nM and 10 pg mL-1 to 1 µg mL-1. The unique structure and excellent electrochemical performance of Ti3C2Tx/Au nanocomposite suggest that it is highly suitable for anchoring biorecognition entities such as antibodies and oligonucleotides for monitoring various deleterious contaminants in agri-food products.


Asunto(s)
Ampicilina , Técnicas Electroquímicas , Fumonisinas , Oro , Límite de Detección , Nanopartículas del Metal , Titanio , Fumonisinas/análisis , Oro/química , Ampicilina/análisis , Ampicilina/química , Nanopartículas del Metal/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Titanio/química , Técnicas Biosensibles/métodos , Leche/química , Antibacterianos/análisis , Electrodos , Contaminación de Alimentos/análisis , Animales
16.
J Basic Microbiol ; 64(6): e2300644, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38412427

RESUMEN

Acinetobacter baumannii, a multidrug-resistant bacterium has become a significant cause of life-threatening infections acquired in hospitals worldwide. The existing drugs used to treat A. baumannii infections are rapidly losing efficacy, and the increasing antimicrobial resistance, which is expected to turn into a global health crisis, underscores the urgency to develop novel prevention and treatment strategies. We reasoned that the discovery of novel virulence targets for vaccine and therapy interventions requires a more enhanced method for the introduction of multiple elements of foreign DNA for genome editing than the current methods of natural transformation techniques. Herein, we employed a novel and a much-improved enhanced technique for the natural transformation of elements of the genome editing system CRISPR-Cas9 to suppress specific genomic regions linked to selectively suppress bacterial virulence. We modified the genome of the laboratory-adapted strain of A. baumannii BAA-747 by targeting the AmpC, as a marker gene, for disruption by three different genomic manipulation strategies, and created mutant strains of A. baumannii that are, at least, fourfold susceptible to ampicillin. This work has established an optimized enhanced natural transformation system that enables efficient genome editing of pathogenic bacteria in a laboratory setting, providing a valuable future tool for exploring the function of unidentified virulence genes in bacterial genomes.


Asunto(s)
Acinetobacter baumannii , Sistemas CRISPR-Cas , Edición Génica , Genoma Bacteriano , Transformación Bacteriana , Acinetobacter baumannii/genética , Acinetobacter baumannii/patogenicidad , Edición Génica/métodos , Genoma Bacteriano/genética , Virulencia/genética , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Ampicilina/farmacología , Infecciones por Acinetobacter/microbiología , Farmacorresistencia Bacteriana Múltiple/genética
17.
Molecules ; 29(10)2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38792087

RESUMEN

In this work, we present the modification of a medical-grade silicone catheter with the N-vinylimidazole monomer using the grafting-from method at room temperature and induced by gamma rays. The catheters were modified by varying the monomer concentration (20-100 vol%) and the irradiation dose (20-100 kGy). Unlike the pristine material, the grafted poly(N-vinylimidazole) chains provided the catheter with hydrophilicity and pH response. This change allowed for the functionalization of the catheters to endow it with antimicrobial features. Thus, the quaternization of amines with iodomethane and bromoethane was performed, as well as the immobilization of silver and ampicillin. The inhibitory capacity of these materials, functionalized with antimicrobial agents, was challenged against Escherichia coli and Staphylococcus aureus strains, showing variable results, where loaded ampicillin was amply better at eliminating bacteria.


Asunto(s)
Escherichia coli , Imidazoles , Siliconas , Staphylococcus aureus , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Siliconas/química , Imidazoles/química , Imidazoles/farmacología , Catéteres/microbiología , Pruebas de Sensibilidad Microbiana , Polivinilos/química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Ampicilina/química , Ampicilina/farmacología , Rayos gamma
18.
Environ Geochem Health ; 46(11): 440, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39316157

RESUMEN

The integration of biochar (BC) production from organic waste with ampicillin (AMP), an emerging pollutant, adsorption is a novel and promising treatment approach. In this study, peanut shells, coffee grounds, digestates, and oyster shells were used for BC production. Among these, the use of anaerobic digestate from food waste fermentation to produce extracts for antibiotic adsorption is relatively unexplored. The pyrolysis temperature was determined using thermogravimetric analysis (TGA) and the materials were characterized with BET, SEM, FTIR, and XRD. The TGA results indicate that PSB, CRB, and DSB underwent pyrolysis involving cellulose, hemicellulose, and lignin, whereas OSB underwent crystal formation. Characterization revealed that DSB has more functional groups, a superior mesoporous structure, appropriate O/C ratio, and trace amounts of calcite crystals, which are favorable for AMP adsorption. Adsorption experiments demonstrate that all four materials adhere to the Freundlich and Langmuir isotherm and Elovich kinetic models, indicating predominant physical adsorption, with some chemical adsorption also present. Thermodynamic studies demonstrate that BC is spontaneous during adsorption and is a heat-absorbing reaction. DSB exhibits the strongest AMP adsorption. A 53.81 mg g-1 adsorbance was obtained at a dosage of 150 mg, pH = 2, and 60 °C. This study introduces innovative approaches for managing waste types and provides data to support the selection of suitable solid wastes for the preparation of BC with excellent adsorption properties. Furthermore, it lays the groundwork for future studies aimed at enhancing the AMP treatment efficacy.


Asunto(s)
Ampicilina , Carbón Orgánico , Carbón Orgánico/química , Adsorción , Ampicilina/química , Antibacterianos/química , Residuos Sólidos , Cinética , Termodinámica , Pirólisis , Termogravimetría
19.
Clin Infect Dis ; 77(5): 768-775, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37279589

RESUMEN

BACKGROUND: Paenibacillus thiaminolyticus may be an underdiagnosed cause of neonatal sepsis. METHODS: We prospectively enrolled a cohort of 800 full-term neonates presenting with a clinical diagnosis of sepsis at 2 Ugandan hospitals. Quantitative polymerase chain reaction specific to P. thiaminolyticus and to the Paenibacillus genus were performed on the blood and cerebrospinal fluid (CSF) of 631 neonates who had both specimen types available. Neonates with Paenibacillus genus or species detected in either specimen type were considered to potentially have paenibacilliosis, (37/631, 6%). We described antenatal, perinatal, and neonatal characteristics, presenting signs, and 12-month developmental outcomes for neonates with paenibacilliosis versus clinical sepsis due to other causes. RESULTS: Median age at presentation was 3 days (interquartile range 1, 7). Fever (92%), irritability (84%), and clinical signs of seizures (51%) were common. Eleven (30%) had an adverse outcome: 5 (14%) neonates died during the first year of life; 5 of 32 (16%) survivors developed postinfectious hydrocephalus (PIH) and 1 (3%) additional survivor had neurodevelopmental impairment without hydrocephalus. CONCLUSIONS: Paenibacillus species was identified in 6% of neonates with signs of sepsis who presented to 2 Ugandan referral hospitals; 70% were P. thiaminolyticus. Improved diagnostics for neonatal sepsis are urgently needed. Optimal antibiotic treatment for this infection is unknown but ampicillin and vancomycin will be ineffective in many cases. These results highlight the need to consider local pathogen prevalence and the possibility of unusual pathogens when determining antibiotic choice for neonatal sepsis.


Asunto(s)
Hidrocefalia , Sepsis Neonatal , Paenibacillus , Sepsis , Recién Nacido , Humanos , Femenino , Embarazo , Uganda/epidemiología , Sepsis/complicaciones , Sepsis/epidemiología , Sepsis/tratamiento farmacológico , Antibacterianos/uso terapéutico , Progresión de la Enfermedad
20.
BMC Microbiol ; 23(1): 5, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36609223

RESUMEN

BACKGROUND: Enterococcus faecalis remains one of the most common pathogens causing infection in surgical patients. Our goal was to evaluate the antibiotic resistance of E. faecalis, causing infections in a surgical clinic, against two antibacterial drugs, ampicillin and teicoplanin. One commonly administered in the past for such infections, ampicillin, and another newer, teicoplanin, which demonstrated exceptionally good efficacy. METHODS: Data from 1882 isolates were retrieved from the microbiology department database during two 5-year periods. Standard biochemical methods were employed for the identification of the isolates. The prevalence of E. faecalis among patients with clinical evidence of infection in a surgical oncology ward was assessed. Confidence interval (CI) as well as standard error (SE) were calculated. Moreover, the annual incidence of E. faecalis infections in this surgical ward was recorded. The susceptibility of E. faecalis to ampicillin and teicoplanin was studied and compared using Fisher's exact test. RESULTS AND CONCLUSION: Results showed that the incidence of E. faecalis infections in the surgical clinic was increasing. Ampicillin, in the later year period, was not statistically different from teicoplanin in treating E. faecalis infections. Consequently, ampicillin seems currently to be an effective antibiotic against such infections that could be used as empiric therapy.


Asunto(s)
Enterococcus faecalis , Teicoplanina , Humanos , Teicoplanina/farmacología , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Ampicilina/farmacología
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