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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120239, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34358786

RESUMO

Antibiotic resistant bacteria pose an increasing threat to global public health, and it is essential that effective detection methods for identifying these organisms. This study assesses the ability of three different analytical approaches that were developed using surface-enhanced Raman spectroscopy (SERS) to differentiate between antibiotic sensitive and resistant bacteria based on their responses to ampicillin exposure, using Escherichia coli O157:H7 as a model bacterium. The approaches tested in this study included a conventional SERS approach of mixing a droplet of bacterial culture with gold nanoparticles, extracellular matrix analysis, and in situ mapping of bacterial cells on a filter membrane. All three of the SERS techniques were able to differentiate between the sensitive and resistant bacterial strains based on peak intensity changes associated with compounds released by the bacteria in response to antibiotic exposure, with extracellular matrix analysis and filter mapping both observed to be more effective than the conventional approach. However, there were significant differences between the spectra obtained from the different techniques and the potential advantages and disadvantages of each approach should be considered when used in the future. This study shows that SERS can be an effective technique for rapid and efficient assessment of ampicillin sensitivity in E. coli, and more work should be done to explore these analytical approaches with other types of bacterial samples.


Assuntos
Escherichia coli O157 , Nanopartículas Metálicas , Ampicilina/farmacologia , Ouro , Análise Espectral Raman
2.
J Chromatogr A ; 1658: 462605, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34662823

RESUMO

The presence of antibiotics in the aquatic environment is becoming one of the main research focus of scientists and policy makers. Proof of that is the inclusion of four antibiotics, amongst which is amoxicillin, in the EU Watch List (WL) (Decision 2020/1161/EU)) of substances for water monitoring. The accurate quantification of amoxicillin in water at the sub-ppb levels required by the WL is troublesome due to its physicochemical properties. In this work, the analytical challenges related to the determination of amoxicillin, and six related penicillins (ampicillin, cloxacillin, dicloxacillin, penicillin G, penicillin V and oxacillin), have been carefully addressed, including sample treatment, sample stability, chromatographic analysis and mass spectrometric detection by triple quadrupole. Given the low recoveries obtained using different solid-phase extraction cartridges, we applied the direct injection of water samples using a reversed-phase chromatographic column that allowed working with 100% aqueous mobile phase. Matrix effects were evaluated and corrected using the isotopically labelled internal standard or correction factors based on signal suppression observed in the analysis of spiked samples. The methodology developed was satisfactorily validated at 50 and 500 ng L - 1 for the seven penicillins studied, and it was applied to different types of water matrices, revealing the presence of ampicillin in one surface water sample and cloxacillin in three effluent wastewater samples.


Assuntos
Amoxicilina , Água , Ampicilina/análise , Cromatografia Líquida de Alta Pressão , União Europeia , Penicilinas/análise , Extração em Fase Sólida
3.
PLoS One ; 16(10): e0257851, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669729

RESUMO

BACKGROUND: Low-level private health facilities (LLPHFs) handle a considerable magnitude of sick children in low-resource countries. We assessed capacity of LLPHFs to manage malaria, pneumonia, diarrhea, and, possible severe bacterial infections (PSBIs) in under-five-year-olds. METHODS: We conducted a cross-sectional survey in 110 LLPHFs and 129 health workers in Mbarara District, Uganda between May and December 2019. Structured questionnaires and observation forms were used to collect data on availability of treatment guidelines, vital medicines, diagnostics, and equipment; health worker qualifications; and knowledge of management of common childhood infections. RESULTS: Amoxicillin was available in 97%, parental ampicillin and gentamicin in 77%, zinc tablets and oral rehydration salts in >90% while artemether-lumefantrine was available in 96% of LLPHF. About 66% of facilities stocked loperamide, a drug contraindicated in the management of diarrhoea in children. Malaria rapid diagnostic tests and microscopes were available in 86% of the facilities, timers/clocks in 57% but only 19% of the facilities had weighing scales and 6% stocked oxygen. Only 4% of the LLPHF had integrated management of childhood illness (IMCI) booklets and algorithm charts for management of common childhood illnesses. Of the 129 health workers, 52% were certificate nurses/midwives and (26% diploma nurses/clinical officers; 57% scored averagely for knowledge on management of common childhood illnesses. More than a quarter (38%) of nursing assistants had low knowledge scores. No notable significant differences existed between rural and urban LLPHFs in most parameters assessed. CONCLUSION: Vital first-line medicines for treatment of common childhood illnesses were available in most of the LLPHFs but majority lacked clinical guidelines and very few had oxygen. Majority of health workers had low to average knowledge on management of the common childhood illnesses. There is need for innovative knowledge raising interventions in LLPHFs including refresher trainings, peer support supervision and provision of job aides.


Assuntos
Infecções Bacterianas/diagnóstico , Diarreia/diagnóstico , Malária/diagnóstico , Pneumonia/diagnóstico , Ampicilina/uso terapêutico , Antimaláricos/uso terapêutico , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Infecções Bacterianas/terapia , Pré-Escolar , Estudos Transversais , Diarreia/epidemiologia , Diarreia/microbiologia , Diarreia/terapia , Feminino , Hidratação/normas , Gentamicinas/uso terapêutico , Humanos , Lactente , Recém-Nascido , Malária/epidemiologia , Malária/parasitologia , Malária/terapia , Masculino , Pneumonia/epidemiologia , Pneumonia/microbiologia , Pneumonia/terapia , Instalações Privadas/tendências , Uganda/epidemiologia , Zinco/uso terapêutico
4.
Chem Commun (Camb) ; 57(80): 10423-10426, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34549224

RESUMO

Herein, we propose an element probe based CRISPR/Cas14 detection platform and apply it to the detection of non-nucleic-acid targets. Combining metal isotope detection and CRISPR/Cas14 biosensing, the sensitive detection of non-nucleic-acid targets could be realized. We designed and optimized the element probe, which proved that Cas14 has a preference for longer lengths in element probe cleavage. Using this method, the quantitative detection of trace aqueous ampicillin can be achieved within 45 minutes at room temperature (25 °C). A detection limit as low as 2.06 nM is obtained with excellent performance in anti-interference tests and complex matrix detection.


Assuntos
Ampicilina/análise , Antibacterianos/análise , Técnicas Biossensoriais/métodos , Sistemas CRISPR-Cas , Monofosfato de Adenosina/análise , Monofosfato de Adenosina/química , Ampicilina/química , Antibacterianos/química , Aptâmeros de Nucleotídeos/química , Proteínas Associadas a CRISPR/química , Endodesoxirribonucleases/química , Limite de Detecção , Rios/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
5.
Braz J Biol ; 83: e247016, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495153

RESUMO

Pheretima posthuma (Vaillant, 1868), a native earthworm of Pakistan and Southeast Asia, has wide utilization in vermicomposting and bioremediation process. In this study, P. posthuma coelomic fluid (PCF) and body paste (PBP) was evaluated as antibacterial agent against ampicillin (AMP) resistant five Gram positive and four Gram negative clinical isolates. The antibacterial effect of different doses (i.e. 25-100 µg/ml) of PCF and PBP along with AMP and azithromycin (AZM) (negative and positive controls, respectively) were observed through disc diffusion and micro-dilution methods. All nine clinical isolates were noticed as AMP resistant and AZM sensitive. Antibacterial effects of PCF and PBP were dose dependent and zone of inhibitions (ZI) against all clinical isolates were between 23.4 ± 0.92 to 0 ± 00 mm. The sensitivity profile of PCF and PBP against clinical isolates was noticed as 44.44 and 55.56%, respectively. Both PCF and PBP showed bacteriostatic (BTS) action against S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Moreover, the cumulative BTS potential of PCF and PBP against all isolates was 66.67 and 55.56%, respectively. The MICs of PCF and PBP were ranged from 50-200 µg/ml against selected isolates. The bacterial growth curves indicated that PCF and PBP inhibited the growth of all isolates at their specific MIC concentrations. However, PBP has better antibacterial potential compared to PCF against selected isolates. Therefore, it is concluded that both PCF and PBP of P. posthuma possess antibacterial and BTS potential against ampicillin resistant clinical isolates. This organism might be considered as a second choice of antibacterial agents and can further be utilized in pharmaceutical industries for novel drug manufacturing by prospecting bioactive potential agents.


Assuntos
Oligoquetos , Staphylococcus aureus , Ampicilina/farmacologia , Animais , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
6.
Int J Mol Sci ; 22(17)2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34502284

RESUMO

Metallo-ß-lactamases (MBLs) are class B ß-lactamases from the metallo-hydrolase-like MBL-fold superfamily which act on a broad range of ß-lactam antibiotics. A previous study on BLEG-1 (formerly called Bleg1_2437), a hypothetical protein from Bacillus lehensis G1, revealed sequence similarity and activity to B3 subclass MBLs, despite its evolutionary divergence from these enzymes. Its relatedness to glyoxalase II (GLXII) raises the possibility of its enzymatic promiscuity and unique structural features compared to other MBLs and GLXIIs. This present study highlights that BLEG-1 possessed both MBL and GLXII activities with similar catalytic efficiencies. Its crystal structure revealed highly similar active site configuration to YcbL and GloB GLXIIs from Salmonella enterica, and L1 B3 MBL from Stenotrophomonas maltophilia. However, different from GLXIIs, BLEG-1 has an insertion of an active-site loop, forming a binding cavity similar to B3 MBL at the N-terminal region. We propose that BLEG-1 could possibly have evolved from GLXII and adopted MBL activity through this insertion.


Assuntos
Bacillus/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Tioléster Hidrolases/química , beta-Lactamases/química , Ampicilina/química , Ampicilina/metabolismo , Proteínas de Bactérias/genética , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Evolução Molecular , Glutationa/análogos & derivados , Glutationa/química , Glutationa/metabolismo , Simulação de Acoplamento Molecular , Filogenia , Conformação Proteica , Stenotrophomonas maltophilia/enzimologia
7.
BMC Infect Dis ; 21(1): 998, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34556028

RESUMO

BACKGROUND: Actinomyces odontolyticus is not commonly recognized as a causative microbe of liver abscess. The detection and identification of A. odontolyticus in laboratories and its recognition as a pathogen in clinical settings can be challenging. However, in the past decades, knowledge on the clinical relevance of A. odontolyticus is gradually increasing. A. odontolyticus is the dominant oropharyngeal flora observed during infancy [Li et al. in Biomed Res Int 2018:3820215, 2018]. Herein we report a case of severe infection caused by A. odontolyticus in an immunocompromised patient with disruption of the gastrointestinal (GI) mucosa. CASE PRESENTATION: We present a unique case of a patient with human immunodeficiency virus infection who was admitted due to liver abscess and was subsequently diagnosed as having coinfection of A. odontolyticus, Streptococcus constellatus, and Candida albicans during the hospital course. The empirical antibiotics metronidazole and ceftriaxone were replaced with the intravenous administration of fluconazole and ampicillin. However, the patient's condition deteriorated, and he died 3 weeks later. CONCLUSION: This report is one of the first to highlight GI tract perforation and its clinical relevance with A. odontolyticus infection. A. odontolyticus infection should be diagnosed early in high-risk patients, and increased attention should be paid to commensal flora infection in immunocompromised individuals.


Assuntos
Infecções por HIV , Abscesso Hepático , Actinomyces , Ampicilina , Ceftriaxona , Infecções por HIV/complicações , Humanos , Abscesso Hepático/diagnóstico , Masculino
8.
BMC Infect Dis ; 21(1): 999, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34556047

RESUMO

BACKGROUND: Infections caused by Enterococcus hirae are common in animals, with instances of transmission to humans being rare. Further, few cases have been reported in humans because of the difficulty in identifying the bacteria. Herein, we report a case of pyelonephritis caused by E. hirae bacteremia and conduct a literature review on E. hirae bacteremia. CASE PRESENTATION: A 57-year-old male patient with alcoholic cirrhosis and neurogenic bladder presented with fever and chills that had persisted for 3 days. Physical examination revealed tenderness of the right costovertebral angle. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) of the patient's blood and urine samples revealed the presence of E. hirae, and pyelonephritis was diagnosed. The patient was treated successfully with intravenous ampicillin followed by oral linezolid for a total of three weeks. CONCLUSION: The literature review we conducted revealed that E. hirae bacteremia is frequently reported in urinary tract infections, biliary tract infections, and infective endocarditis and is more likely to occur in patients with diabetes, liver cirrhosis, and chronic kidney disease. However, mortality is not common because of the high antimicrobial susceptibility of E. hirae. With the advancements in MALDI-TOF MS, the number of reports of E. hirae infections has also increased, and clinicians need to consider E. hirae as a possible causative pathogen of urinary tract infections in patients with known risk factors.


Assuntos
Bacteriemia , Pielonefrite , Ampicilina , Animais , Bacteriemia/complicações , Bacteriemia/tratamento farmacológico , Streptococcus faecium ATCC 9790 , Humanos , Cirrose Hepática Alcoólica/complicações , Masculino , Pessoa de Meia-Idade , Pielonefrite/complicações , Pielonefrite/tratamento farmacológico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
PLoS One ; 16(8): e0255410, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34343185

RESUMO

INTRODUCTION: Newborn sepsis accounts for more than a third of neonatal deaths globally and one in five neonatal deaths in Ethiopia. The first-line treatment recommended by WHO is the combination of gentamicin with ampicillin or benzylpenicillin. Gram-negative bacteria (GNB) are increasingly resistant to previously effective antibiotics. OBJECTIVES: Our goal was to estimate the prevalence of antibiotic-resistant gram-negative bacteremia and identify risk factors for antibiotic resistance, among newborns with GNB sepsis. METHODS: At a tertiary hospital in Ethiopia, we enrolled a cohort pregnant women and their newborns, between March and December 2017. Newborns who were followed up until 60 days of life for clinical signs of sepsis. Among the newborns with clinical signs of sepsis, blood samples were cultured; bacterial species were identified and tested for antibiotic susceptibility. We described the prevalence of antibiotic resistance, identified newborn, maternal, and environmental factors associated with multidrug resistance (MDR), and combined resistance to ampicillin and gentamicin (AmpGen), using multivariable regression. RESULTS: Of the 119 newborns with gram-negative bacteremia, 80 (67%) were born preterm and 82 (70%) had early-onset sepsis. The most prevalent gram-negative species were Klebsiella pneumoniae 94 (79%) followed by Escherichia coli 10 (8%). Ampicillin resistance was found in 113 cases (95%), cefotaxime 104 (87%), gentamicin 101 (85%), AmpGen 101 (85%), piperacillin-tazobactam 47 (39%), amikacin 10 (8.4%), and Imipenem 1 (0.8%). Prevalence of MDR was 88% (n = 105). Low birthweight and late-onset sepsis (LOS) were associated with higher risks of AmpGen-resistant infections. All-cause mortality was higher among newborns treated with ineffective antibiotics. CONCLUSION: There was significant resistance to current first-line antibiotics and cephalosporins. Additional data are needed from primary care and community settings. Amikacin and piperacillin-tazobactam had lower rates of resistance; however, context-specific assessments of their potential adverse effects, their local availability, and cost-effectiveness would be necessary before selecting a new first-line regimen to help guide clinical decision-making.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Bactérias Gram-Negativas/crescimento & desenvolvimento , Infecções por Bactérias Gram-Negativas/epidemiologia , Sepse Neonatal/microbiologia , Ampicilina/farmacologia , Cefalosporinas/farmacologia , Etiópia/epidemiologia , Feminino , Gentamicinas/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Recém-Nascido , Masculino , Viabilidade Microbiana/efeitos dos fármacos , Sepse Neonatal/epidemiologia , Penicilina G/farmacologia , Gravidez , Prevalência , Centros de Atenção Terciária
10.
Analyst ; 146(17): 5413-5420, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34346408

RESUMO

In this study, a novel, rapid and ultrasensitive fluorescence strategy using the three-dimensional (3D) dynamic DNA walker (DW)-induced branched hybridization chain reaction (bHCR) has been proposed for the detection of ampicillin (AMP). The sensing system was composed of an Nt·Bbvcl-powered DNA walker blocked by an AMP aptamer, hairpin-shaped DNA track probe (TP) and four kinds of metastable hairpin probes as the substrates of bHCR, which triggered the formation of the split G-quadruplex as the signal molecule. Due to the reasonable design, the specific binding between AMP and its aptamer activated the DW, and the DW moved on the surface of the gold nanoparticles (AuNPs) with the help of Nt·Bbvcl to produce primer probes (PPs), which induced bHCR. The products of the bHCR gathered two split G-quadruplex sequences together to form one complete G-quadruplex. The formed G-quadruplex emitted a strong fluorescence signal in the presence of thioflavin-T (ThT) to achieve the purpose of detecting AMP. The sensitivity of this method was greatly improved by the use of the 3D DNA walker and bHCR. The split G-quadruplex enhanced the signal-to-noise ratio (SNR). Under the optimal experimental conditions, a good correlation was obtained between the fluorescence intensity of the sensing system and the concentration of AMP ranging from 5 pM to 500 nM with a limit of detection (LOD) of 3.68 pM. Simultaneously, the method has been applied to the detection of antibiotics in spiked milk samples with satisfactory results.


Assuntos
Técnicas Biossensoriais , Quadruplex G , Nanopartículas Metálicas , Ampicilina , DNA/genética , Ouro , Limite de Detecção , Hibridização de Ácido Nucleico
11.
Medicine (Baltimore) ; 100(31): e26839, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34397853

RESUMO

RATIONALE: Listeria monocytogenes infective encephalitis is a rare phenomenon, which is more common in people with changed eating habits and immunodeficiency. To the best of our knowledge, listeria brain abscess is even more rare. In this case report, we summarized the clinical characteristics of listeria brain abscess, in order to explore the diagnosis and treatment of Listeria brain abscess, and raise awareness and attention to the disease. PATIENT CONCERNS: A 64-years-old female patient presented to our institution with 4 days of right arm and leg weakness, the salient past history of the patient was nephrotic syndrome, membranous nephropathy diagnosed 6 months prior, for which she was prescribed glucocorticoids and cyclophosphamide. DIAGNOSIS: Listeria monocytogenes was cultured in the blood of the patient. Comprehensive medical history and imaging features, she was diagnosed as listeria brain abscess. INTERVENTIONS: The patient underwent ampicillin combined with meropenem but not surgery. OUTCOMES: The patient recovered without complications. At a 3-month follow-up visit, the condition was better than that before treatment. LESSONS: Listeria brain abscess is an unusual form of listeriosis, its clinical manifestations lack specificity. Early accurate diagnosis and standardized treatment can effectively promote the recovery of neurological function as well as reduce the morbidity and mortality and improve the prognosis.


Assuntos
Ampicilina/administração & dosagem , Abscesso Encefálico , Listeria monocytogenes/isolamento & purificação , Meropeném/administração & dosagem , Neuroimagem/métodos , Paresia , Antibacterianos/administração & dosagem , Abscesso Encefálico/diagnóstico , Abscesso Encefálico/tratamento farmacológico , Abscesso Encefálico/microbiologia , Abscesso Encefálico/fisiopatologia , Feminino , Humanos , Hospedeiro Imunocomprometido , Pessoa de Meia-Idade , Exame Neurológico/métodos , Paresia/diagnóstico , Paresia/etiologia , Resultado do Tratamento
12.
J Med Case Rep ; 15(1): 433, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34404462

RESUMO

INTRODUCTION: Haemophilus influenzae is a Gram-negative coccobacillus that can cause many different kinds of infection, ranging from mild ear infection to life-threatening diseases like epiglottitis and meningitis. Encapsulated type b Haemophilus influenzae was most commonly responsible for Haemophilus influenzae meningitis in children before introduction of Haemophilus influenzae conjugate vaccine. None or partially immunized children are acquiring meningitis owing to resistant strains of Haemophilus influenzae, namely beta-lactamase-negative ampicillin-resistant strain. CASE PRESENTATION: We reported the case of a 2-year-old Emirati boy who presented to our emergency department with fever, diarrhea, vomiting, and fluctuating levels of consciousness. He was developmentally normal with no significant past medical history, except he was partially immunized. Earlier, he had been treated for acute gastroenteritis with intravenous fluids and antiemetics in another hospital and was discharged. His parents escorted him to our emergency department as he became very drowsy. Examination revealed that he was in septic shock. He was immediately treated with oxygen, intravenous antibiotics, and fluids after performing septic workup. He was then shifted to intensive care unit. Blood culture and cerebrospinal fluid Gram stain confirmed diagnosis of beta-lactamase-negative ampicillin-resistant Haemophilus influenzae. He was started on intravenous ceftriaxone, acyclovir, and dexamethasone. He still spiked fever after 1 week. Therefore, ceftriaxone was replaced by meropenem. He recovered well with no sequelae. CONCLUSION: This case highlights atypical presentation of life-threatening illness along with microbial resistance that had positive outcome due to timely diagnosis and aggressive management by a multidisciplinary team.


Assuntos
Haemophilus influenzae tipo b , Meningite por Haemophilus , Meningite , Ampicilina , Antibacterianos/uso terapêutico , Pré-Escolar , Humanos , Masculino , Meningite/tratamento farmacológico , Meningite por Haemophilus/tratamento farmacológico , beta-Lactamases
13.
Molecules ; 26(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34443650

RESUMO

A chemical investigation into endozoic fungus Aspergillus niger L14 derived from the marine sponge of Reniera japonica collected off Xinghai Bay (China) resulted in the isolation of two dimeric naphtho-γ-pyrones, fonsecinone A (1) and isoaurasperone A (2). Through a combination of ECD spectra and X-ray diffraction analysis, the chiral axes of compounds 1 and 2 were unambiguously determined as Rα-configurations. Bioassay results indicated that these substances exhibited remarkably inhibitory effects on human pathogens Helicobacter pylori G27 and 159 with MIC values of ≤4 µg/mL, which are similar to those of the positive control, ampicillin sodium. To the best of our knowledge, this is the first report on absolute configuration of 1 and crystallographic data of 2, as well as their potent anti-H. pylori activities.


Assuntos
Antibacterianos/metabolismo , Antibacterianos/farmacologia , Aspergillus niger/metabolismo , Helicobacter pylori/efeitos dos fármacos , Poríferos/metabolismo , Ampicilina/farmacologia , Animais , Testes de Sensibilidade Microbiana , Pironas/metabolismo , Pironas/farmacologia
14.
Biosensors (Basel) ; 11(8)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34436085

RESUMO

Since the discovery of antibiotics, the emergence of antibiotic resistance has become a global issue that is threatening society. In the era of antibiotic resistance, finding the proper antibiotics through antibiotic susceptibility testing (AST) is crucial in clinical settings. However, the current clinical process of AST based on the broth microdilution test has limitations on scalability to expand the number of antibiotics that are tested with various concentrations. Here, we used color-coded droplets to expand the multiplexing of AST regarding the kind and concentration of antibiotics. Color type and density differentiate the kind of antibiotics and concentration, respectively. Microscopic images of a large view field contain numbers of droplets with different testing conditions. Image processing analysis detects each droplet, decodes color codes, and measures the bacterial growth in the droplet. Testing E. coli ATCC 25922 with ampicillin, gentamicin, and tetracycline shows that the system can provide a robust and scalable platform for multiplexed AST. Furthermore, the system can be applied to various drug testing systems, which require several different testing conditions.


Assuntos
Testes de Sensibilidade Microbiana , Ampicilina , Antibacterianos , Técnicas Biossensoriais , Resistência Microbiana a Medicamentos , Desenho de Equipamento , Escherichia coli , Processamento de Imagem Assistida por Computador , Técnicas Analíticas Microfluídicas , Tetraciclina , Fatores de Tempo
15.
Molecules ; 26(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206584

RESUMO

In this work, a simple and rapid method based on the lateral flow assay (LFA) has been developed for the detection of dual antibiotics. To achieve the quantitative assay and to reduce the non-specific adsorption, an internal system has been developed. A non-specific DNA was exploited as an internal standard and could be recognized by the DNA marker that was coated at the internal line. Two different kinds of aptamers were applied to recognize ampicillin (AMP) and kanamycin (KAM), and the distance between the detection line and conjugate pad was then optimized. Under the optimum conditions, the quantitative assays of AMP (R2 = 0.984) and KAM (R2 = 0.990) were achieved with dynamic ranges of 0.50 to 500.0 ng/L, and of 0.50 to 1000.0 ng/L, respectively. The LOQs of AMP and KAM were 0.06 ng/L and 0.015 ng/L, respectively. Finally, the proposed method has been successfully applied to analyze aquaculture water, tap water, and lake water, and hospital wastewater, indicating the established method could be used to monitor the environment.


Assuntos
Ampicilina/análise , Aptâmeros de Nucleotídeos/química , Canamicina/análise , Água/análise
16.
BMC Infect Dis ; 21(1): 633, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210285

RESUMO

BACKGROUND: The bacterium Campylobacter insulaenigrae was first isolated from marine mammals of Scotland in 2004. Only one case of C. insulaenigrae infection in humans has been previously reported. CASE PRESENTATION: An 89-year-old Japanese man without dementia was admitted to our hospital, because he presented with a fever of 38 °C and weakness in right leg since 5 days. He had organized chronic subdural hematoma (CSH), and no history of pre-infection. At the time of admission, he had paralysis of the extraocular muscle, ataxia, and low manual muscle test score of the right side. He was suspected to have Miller Fisher syndrome; however, these symptoms improved without any treatment. On day 22 in the hospital, the patient presented a fever of 38.8 °C, left cranial nerve disorder, and hemiplegia. On day 25, the patient presented with signs of meningeal irritation; cerebrospinal fluid examination indicated an increase in the number of apocytes and a low glucose level. A contrast magnetic resonance imaging (MRI) scan of the patient's head indicated a contrast enhancement effect in his right meninges. The blood culture showed presence of spirillums; 16S rRNA gene sequencing confirmed that the spirillums in the blood culture were Campylobacter insulaenigrae (C. insulaenigrae). We started treatment with meropenem for bacteremia and meningitis. When the symptoms improved, meropenem was replaced with ampicillin, based on the result of the drug sensitivity test. The treatment continued for 4 weeks. CONCLUSIONS: We report the first case of meningitis caused by C. insulaenigrae bacteremia in humans, and the second clinical report of C. insulaenigrae infection in humans. The bacterial strains isolated from humans and marine mammals had different genotypes. This suggests that different genotypes could be responsible for differences in the hosts. Further case studies are needed to establish the reasons behind the difference in the manifestations of C. insulaenigrae infections reported so far.


Assuntos
Bacteriemia/etiologia , Infecções por Campylobacter/diagnóstico , Campylobacter/isolamento & purificação , Meningite/etiologia , Idoso de 80 Anos ou mais , Ampicilina/uso terapêutico , Bacteriemia/tratamento farmacológico , Infecções por Campylobacter/tratamento farmacológico , Humanos , Japão/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Meningite/tratamento farmacológico , Meropeném/uso terapêutico , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S , Análise de Sequência de RNA
17.
Curr Oncol ; 28(4): 2466-2480, 2021 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-34287268

RESUMO

Antibiotics are considered the cornerstone of modern medicine; however, currently, antibiotic resistance has become a global health issue. Antibiotics also find new uses in the treatment of other pathologies as well as cancer. The present study aimed to verify the impact of tetracycline and ampicillin in a colorectal adenocarcinoma cell line, HT-29. The effects of the two antibiotics on cell viability and nucleus were evaluated by the means of MTT assay and the Hoechst staining method, respectively. The irritant potential at vascular level of the chorioallantoic membrane was tested by the HET-CAM assay. Treatment of HT-29 cells with the two antibiotics determined different effects: (i) tetracycline induced a dose- and time-dependent cytotoxic effect characterized by decreased cell viability, changes in cells morphology, apoptotic features (nuclear fragmentation), and inhibition of cellular migration, whereas (ii) ampicillin exerted a biphasic response-cytotoxic at low doses and proliferative at high concentrations. In terms of effect on blood vessels, both antibiotics exerted a mild irritant effect. These results are promising and could be considered as starting point for further in vitro studies to define the molecular mechanisms involved in the cytotoxic/proliferative effects.


Assuntos
Adenocarcinoma , Neoplasias Colorretais , Adenocarcinoma/tratamento farmacológico , Ampicilina/farmacologia , Antibacterianos/farmacologia , Sobrevivência Celular , Neoplasias Colorretais/tratamento farmacológico , Células HT29 , Humanos , Tetraciclinas/farmacologia
18.
Comp Med ; 71(3): 203-209, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34088363

RESUMO

Over the last decade, interest in the role of the microbiome in health and disease has increased. The use of germ-free animals and depletion of the microbial flora using antimicrobials are 2 methods commonly used to study the microbiome in laboratory mice. Germ-free mice are born, raised, and studied in isolators in the absence of any known microbes; however, the equipment, supplies, and training required for the use of these mice can be costly and time-consuming. The use of antibiotics to decrease the microbial flora does not require special equipment, can be used for any mouse strain, and is relatively inexpensive; however, mice treated in this manner still retain microbes and they do not live in a germ-free environment. One commonly used antibiotic cocktail regimen uses ampicillin, neomycin, metronidazole, and vancomycin in the drinking water for 2 to 4 wk. We found that the palatability of this mixture is low, resulting in weight loss and leading to removal of mice from the study. The addition of sucralose to the medicated water and making wet food (mash) with the medicated water improved intake; however, the low palatability still resulted in a high number of mice requiring removal. The current study evaluated a new combination of antibiotics designed to reduce the gut microbiota while maintaining body weights. C57BL/6NCrl mice were placed on one of the following drinking water regimens: ampicillin/neomycin/metronidazole/vancomycin water (n = 16), enrofloxacin/ampicillin water ( n = 12), or standard reverse osmosis deionized water (RODI) ( n = 11). During an 8 day regimen, mice were weighed and water consumption was measured. Feces were collected before and after 8 d of treatment. Quantitative real-time PCR (real-time qPCR) for 16S bacterial ribosome was performed on each sample, and values were compared among groups. The combination of enrofloxacin and ampicillin improved water intake, together with a greater reduction in gut flora.


Assuntos
Microbioma Gastrointestinal , Ampicilina/farmacologia , Animais , Antibacterianos/farmacologia , Fezes , Feminino , Camundongos , Camundongos Endogâmicos C57BL
19.
BMC Infect Dis ; 21(1): 531, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34090359

RESUMO

BACKGROUND: Group B Streptococcus (GBS) is an important cause of invasive infection in neonates and infants. Cerebrospinal fluid (CSF) findings and culture may not show evidence of infection early in GBS meningitis. Next-generation sequencing (NGS) has the potential to detect microbial genetic material in patients with infectious diseases. We report two cases of infantile sepsis of GBS meningitis with negative results for CSF culture tests, but positive results for NGS analysis. CASE PRESENTATION: Patient 1 was a 22-day-old male infant diagnosed with sepsis and meningitis. His CSF findings showed pleocytosis, decreased glucose, and increased protein levels. However, CSF and blood culture results at admission were negative. He received a total of 3 weeks of treatment with ampicillin and cefotaxime, and showed clinical improvement. GBS was detected through NGS analysis of CSF collected at admission. Patient 2 was a 51-day-old male infant with sepsis. CSF findings on admission were normal, and blood and CSF cultures were also negative. Intravenous ampicillin and cefotaxime treatment were initiated. Treatment was de-escalated to ampicillin alone because Enterococcus faecalis was cultured from urine. He was discharged after a total of 1 week of antibiotic treatment. Six days after discharge, he was re-hospitalized for sepsis. Blood and CSF cultures were negative, and E. faecalis was again cultured from urine. He received a total of 3 weeks of ampicillin treatment for enterococcal-induced nephritis and did not relapse thereafter. NGS pathogen searches were retrospectively performed on both blood and CSF collected at the first and second admission. GBS was detected in the CSF collected at the first admission, but no significant pathogen was detected in the other samples. Inadequate treatment for GBS meningitis at the first admission may have caused the recurrence of the disease. CONCLUSION: Infantile sepsis may present bacterial meningitis that is not diagnosed by either culture testing or CSF findings. NGS analysis for CSF may be useful for confirming the diagnosis of bacterial meningitis.


Assuntos
Antibacterianos/uso terapêutico , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/tratamento farmacológico , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/tratamento farmacológico , Ampicilina/uso terapêutico , Cefotaxima/uso terapêutico , Líquido Cefalorraquidiano/microbiologia , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Recém-Nascido , Masculino , Meningites Bacterianas/microbiologia , Estudos Retrospectivos , Sepse/diagnóstico , Sepse/tratamento farmacológico , Sepse/microbiologia , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/genética , Streptococcus agalactiae/isolamento & purificação , Urina/microbiologia
20.
Methods Mol Biol ; 2323: 67-73, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34086274

RESUMO

For structural, biochemical, or pharmacological studies, it is required to have pure RNA in large quantities. We previously devised a generic approach that allows for efficient in vivo expression of recombinant RNA in Escherichia coli. We have extended the "tRNA scaffold" method to RNA-protein coexpression in order to express and purify RNA by affinity in native condition. As a proof of concept, we present the expression and the purification of the AtRNA-mala in complex with the MS2 coat protein.


Assuntos
Cromatografia de Afinidade/métodos , Clonagem Molecular/métodos , Proteínas de Escherichia coli/isolamento & purificação , Escherichia coli/química , Proteínas de Ligação a RNA/isolamento & purificação , RNA/isolamento & purificação , Ampicilina/farmacologia , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Capsídeo , Cloranfenicol/farmacologia , Simulação por Computador , Resistência Microbiana a Medicamentos/genética , Eletroforese em Gel de Poliacrilamida/métodos , Escherichia coli/genética , Proteínas de Escherichia coli/biossíntese , Levivirus/genética , Modelos Moleculares , Conformação de Ácido Nucleico , Regiões Operadoras Genéticas , Plasmídeos/genética , RNA/biossíntese , RNA Bacteriano/genética , RNA Bacteriano/isolamento & purificação , RNA Viral/genética , RNA Viral/isolamento & purificação , Proteínas de Ligação a RNA/biossíntese
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