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1.
Methods Mol Biol ; 2855: 3-19, 2025.
Artigo em Inglês | MEDLINE | ID: mdl-39354298

RESUMO

Metabolomics is the scientific field with the eager goal to comprehensively analyze the entirety of all small molecules of a biological system, i.e., the metabolome. Over the last few years, metabolomics has matured to become an analytical cornerstone of life science research across diverse fields, from fundamental biochemical applications to preclinical studies, including biomarker discovery and drug development. In this chapter, we provide an introduction to (pre)clinical metabolomics. We define key metabolomics aspects and provide the basis to thoroughly understand the relevance of this field in a biological and clinical context. We present and explain state-of-the-art analytical technologies devoted to metabolomic analysis as well as emerging technologies, discussing both strengths and weaknesses. Given the ever-increasing demand for handling complex datasets, the role of bioinformatics approaches in the context of metabolomic analysis is also illustrated.


Assuntos
Biologia Computacional , Metaboloma , Metabolômica , Metabolômica/métodos , Humanos , Biologia Computacional/métodos , Animais , Biomarcadores/metabolismo , Espectrometria de Massas/métodos
2.
J Nanobiotechnology ; 22(1): 596, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39354525

RESUMO

Early diagnosis and treatment of gastric cancer (GC) play a vital role in improving efficacy, reducing mortality and prolonging patients' lives. Given the importance of early detection of gastric cancer, an electrochemical biosensor was developed for the ultrasensitive detection of miR-19b-3p by integrating MoS2-based nanozymes, hybridization chain reaction (HCR) with enzyme catalyzed reaction. The as-prepared MoS2-based nanocomposites were used as substrate materials to construct nanoprobes, which can simultaneously load probe DNA and HCR initiator for signal amplification. Moreover, the MoS2-based nanocomposites are also employed as nanozymes to amplify electrochemical response. The presence of miR-19b-3p induced the assembly of MoS2-based nanoprobes on the electrode surface, which can activate in-situ HCR reaction to load a large number of horseradish peroxidase (HRP) for signal amplification. Coupling with the co-catalytic ability of HRP and MoS2-based nanozymes, the designed electrochemical biosensor can detect as low as 0.7 aM miR-19b-3p. More importantly, this biosensor can efficiently analyze miR-19b-3p in clinical samples from healthy people and gastric cancer patients due to its excellent sensitivity and selectivity, suggesting that this biosensor has a potential application in early diagnosis of disease.


Assuntos
Técnicas Biossensoriais , Dissulfetos , Técnicas Eletroquímicas , Peroxidase do Rábano Silvestre , MicroRNAs , Molibdênio , Neoplasias Gástricas , Neoplasias Gástricas/diagnóstico , Humanos , MicroRNAs/genética , Molibdênio/química , Técnicas Eletroquímicas/métodos , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Técnicas Biossensoriais/métodos , Dissulfetos/química , Hibridização de Ácido Nucleico , Nanocompostos/química , Limite de Detecção
3.
Pathogens ; 13(9)2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39338917

RESUMO

Listeriosis is one of the most serious foodborne diseases under surveillance, with an overall mortality rate in the EU currently being high at 18.1%. Therefore, this study aims to investigate Listeria monocytogenes strains isolated from clinical and food samples for susceptibility to antimicrobials, presence of virulence factors, and genetic diversity. Species were identified using the MALDI-TOF, resistance to 11 antibiotics was determined according to EUCAST guidelines, and multiplex PCR was used for serotyping and detecting virulence genes. Strains were genotyped using the PFGE method. Clinical strains showed full sensitivity to all tested antibiotics. In total, 33.3% of strains from food products were found to be resistant to ciprofloxacin and 4.2% to tetracycline. Most of the tested isolates (79.2%) belonged to serotype 1/2a-3a, and the rest (20.8%) belonged to serotype 4ab-4b,4d-4e. Five virulence genes (prfA, hlyA, plcB, inlA, and lmo2672) were detected in all strains studied. The llsX gene was the least common, in 37.5% of clinical strains and 18.75% of strains isolated from food products. Among the analyzed strains, 13 strains displayed unique PFGE profiles. The other 11 strains belong to 3 clusters of pulsotypes: cluster 1 (2 strains), cluster 2 (6 strains), and cluster 3 (2 strains). The percentage of hospitalizations and deaths of Polish patients with listeriosis indicates the seriousness of this disease, especially in an aging society, while the molecular testing of clinical strains has been rarely performed, which makes it difficult to determine the source of infection.

4.
Glia ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39228066

RESUMO

DNAJB6 is a suppressor of α-synuclein aggregation in vivo and in vitro. DNAJB6 is strongly expressed in the brain, and its overall protein expression is altered in neurodegenerative conditions such as Parkinson's Disease (PD) and Multiple System Atrophy (MSA). These two diseases are characterized by accumulation of aggregated α-synuclein in neurons and oligodendrocytes, respectively. To further explore this, we employed post-mortem normal human brain material to investigate the regional and cell type specific protein expression of DNAJB6. We found that the DNAJB6 protein is ubiquitously expressed across various regions of the brain. Notably, we demonstrate for the first time that DNAJB6 is present in nearly half (41%-53%) of the oligodendrocyte population and in the majority (68%-80%) of neurons. However, DNAJB6 was only sparsely present in other cell types such as astrocytes and microglia. Given that α-synuclein aggregation in oligodendrocytes is a hallmark of MSA, we investigated DNAJB6 presence in MSA brains compared to control brains. We found no significant difference in the percentage of oligodendrocytes where DNAJB6 was present in MSA brains relative to control brains. In conclusion, our results reveal an expression of the DNAJB6 protein across various regions of the human brain, and that DNAJB6 is almost exclusively present in neurons and oligodendrocytes. Since prior studies have shown that PD and MSA brains have altered levels of DNAJB6 relative to control brains, DNAJB6 may be an interesting target for drug development.

5.
Biosens Bioelectron ; 267: 116768, 2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39255675

RESUMO

Nitroreductase (NTR) is widely regarded as a biomarker whose enzymatic activity correlates with the degree of hypoxia in solid malignant tumors. Herein, we utilized 2-dimethylamino-7-hydroxynaphthalene as fluorophore linked diverse nitroaromatic groups to obtain four NTR-activatable two-photon fluorescent probes based on covalent assembly strategy. With the help of computer docking simulation and in vitro assay, the sulfonate-based probe XN3 was proved to be able to identify NTR activity with best performances in rapid response, outstanding specificity, and sensitivity in comparison with the other three probes. Furthermore, XN3 could detect the degree of hypoxia by monitoring NTR activity in kinds of cancer cells with remarkable signal-to-noise ratios. In cancer tissue sections of the breast and liver in mice, XN3 had the ability to differentiate between healthy and tumorous tissues, and possessed excellent fluorescence stability, high tissue penetration and low tissue autofluorescence. Finally, XN3 was successfully utilized for in situ visualizing NTR activities in human transverse colon and rectal cancer tissues, respectively. The findings suggested that XN3 could directly identify the boundary between cancer and normal tissues by monitoring NTR activities, which provides a new method for imaging diagnosis and intraoperative navigation of tumor tissue.

6.
Artigo em Inglês | MEDLINE | ID: mdl-39190041

RESUMO

Research on anxiety faces challenges due to the wide range of symptoms, making it difficult to determine if different aspects of anxiety are linked to distinct neurobiological processes. Both alterations in functional brain connectivity (FC) and monoaminergic neurotransmitter systems are implicated as potential neural bases of anxiety. We aimed to investigate whole-brain FC involving monoaminergic nuclei and its association with anxiety dimensions in 178 non-clinical participants. Nine anxiety-related scales were used, encompassing trait and state anxiety scores, along with measures of cost-probability, hypervigilance, reward-punishment sensitivity, uncertainty, and trait worry. Resting-state functional magnetic resonance imaging data were acquired, focusing on seven brainstem regions representing serotonergic, dopaminergic, and noradrenergic nuclei, with their FC patterns voxel-wise correlated with the scales. All models underwent family-wise-error correction for multiple comparisons. We observed intriguing relationships: trait and state anxiety scores exhibited opposing correlations in FC between the dorsal raphe nucleus and the paracingulate gyrus. Additionally, we identified shared neural correlates, such as a negative correlation between the locus coeruleus and the frontal pole. This connection was significantly associated with scores on measures of probability, hypervigilance, reward sensitivity, and trait worry. These findings underscore the intricate interplay between anxiety dimensions and subcortico-cortical FC patterns, shedding light on the underlying neural mechanisms governing anxiety.

7.
Biosensors (Basel) ; 14(8)2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39194620

RESUMO

To achieve the accurate recognition of biomarkers or pathological characteristics within tissues or cells, in situ detection using biosensor technology offers crucial insights into the nature, stage, and progression of diseases, paving the way for enhanced precision in diagnostic approaches and treatment strategies. The implementation of needle-shaped biosensors (N-biosensors) presents a highly promising method for conducting in situ measurements of clinical biomarkers in various organs, such as in the brain or spinal cord. Previous studies have highlighted the excellent performance of different N-biosensor designs in detecting biomarkers from clinical samples in vitro. Recent preclinical in vivo studies have also shown significant progress in the clinical translation of N-biosensor technology for in situ biomarker detection, enabling highly accurate diagnoses for cancer, diabetes, and infectious diseases. This article begins with an overview of current state-of-the-art benchtop N-biosensor designs, discusses their preclinical applications for sensitive diagnoses, and concludes by exploring the challenges and potential avenues for next-generation N-biosensor technology.


Assuntos
Técnicas Biossensoriais , Humanos , Biomarcadores , Medicina de Precisão , Animais
8.
Ann Clin Microbiol Antimicrob ; 23(1): 80, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39182092

RESUMO

BACKGROUND: Due to the increasing emergence of antibiotic resistance in Enterococcus faecalis (E. faecalis), it indicated as potentially opportunistic pathogen causing various healthcare-associated and life-threatening diseases around the world. OBJECTIVE: The aim of this meta-analysis was to evaluate the weighted pooled resistance rates in clinical E. faecalis isolates based on over time, areas, antimicrobial susceptibility testing (AST), and infection source. METHODS: We searched the studies in PubMed, Scopus, and Web of Science (November 30, 2022). All statistical analyses were carried out using the statistical package R. RESULTS: The analysis encompassed a total of 74 studies conducted in 28 countries. According to the meta-regression, the chloramphenicol, fosfomycin, imipenem, linezolid, minocycline, norfloxacin, quinupristin-dalfopristin, and tetracycline resistance rate increased over time. Analysis revealed statistically significant differences in antibiotic resistance rates for ampicillin, chloramphenicol, erythromycin, gentamicin, penicillin, rifampicin, teicoplanin, tetracycline, and vancomycin across various countries. CONCLUSIONS: Globally, the prevalence of drug resistant E. faecalis strains are on the increase over time. Daptomycin and tigecycline can be an effective agent for the treatment of clinical E. faecalis infections. Considering the low prevalence of antibiotic resistance in continents of Europe and Australia, it is suggested to take advantage of their preventive strategies in order to obtain efficient results in other places with high prevalence of resistance.


Assuntos
Antibacterianos , Enterococcus faecalis , Infecções por Bactérias Gram-Positivas , Testes de Sensibilidade Microbiana , Enterococcus faecalis/efeitos dos fármacos , Humanos , Antibacterianos/farmacologia , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/epidemiologia , Farmacorresistência Bacteriana , Saúde Global , Farmacorresistência Bacteriana Múltipla
9.
Microb Genom ; 10(8)2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39213166

RESUMO

Campylobacter is the leading bacterial cause of infectious intestinal disease, but the pathogen typically accounts for a very small proportion of the overall stool microbiome in each patient. Diagnosis is even more difficult due to the fastidious nature of Campylobacter in the laboratory setting. This has, in part, driven a change in recent years, from culture-based to rapid PCR-based diagnostic assays which have improved diagnostic detection, whilst creating a knowledge gap in our clinical and epidemiological understanding of Campylobacter genotypes - no isolates to sequence. In this study, direct metagenomic sequencing approaches were used to assess the possibility of replacing genome sequences with metagenome sequences; metagenomic sequencing outputs were used to describe clinically relevant attributes of Campylobacter genotypes. A total of 37 diarrhoeal stool samples with Campylobacter and five samples with an unknown pathogen result were collected and processed with and without filtration, DNA was extracted, and metagenomes were sequenced by short-read sequencing. Culture-based methods were used to validate Campylobacter metagenome-derived genome (MDG) results. Sequence output metrics were assessed for Campylobacter genome quality and accuracy of characterization. Of the 42 samples passing quality checks for analysis, identification of Campylobacter to the genus and species level was dependent on Campylobacter genome read count, coverage and genome completeness. A total of 65% (24/37) of samples were reliably identified to the genus level through Campylobacter MDG, 73% (27/37) by culture and 97% (36/37) by qPCR. The Campylobacter genomes with a genome completeness of over 60% (n=21) were all accurately identified at the species level (100%). Of those, 72% (15/21) were identified to sequence types (STs), and 95% (20/21) accurately identified antimicrobial resistance (AMR) gene determinants. Filtration of stool samples enhanced Campylobacter MDG recovery and genome quality metrics compared to the corresponding unfiltered samples, which improved the identification of STs and AMR profiles. The phylogenetic analysis in this study demonstrated the clustering of the metagenome-derived with culture-derived genomes and revealed the reliability of genomes from direct stool sequencing. Furthermore, Campylobacter genome spiking percentages ranging from 0 to 2% total metagenome abundance in the ONT MinION sequencer, configured to adaptive sequencing, exhibited better assembly quality and accurate identification of STs, particularly in the analysis of metagenomes containing 2 and 1% of Campylobacter jejuni genomes. Direct sequencing of Campylobacter from stool samples provides clinically relevant and epidemiologically important genomic information without the reliance on cultured genomes.


Assuntos
Infecções por Campylobacter , Campylobacter , Fezes , Sequenciamento Completo do Genoma , Fezes/microbiologia , Humanos , Campylobacter/genética , Campylobacter/isolamento & purificação , Campylobacter/classificação , Sequenciamento Completo do Genoma/métodos , Infecções por Campylobacter/microbiologia , Genoma Bacteriano , Metagenoma , Metagenômica/métodos , Diarreia/microbiologia , Filogenia
10.
Vet Sci ; 11(7)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39057969

RESUMO

(1) Background: Feline herpesvirus (FHV-1) is a significant pathogen in cats, causing respiratory and ocular diseases with consequential economic and welfare implications. (2) Methods: This study aimed to isolate and characterize FHV-1 from clinical samples and assess its pathogenicity. We collected 35 nasal and ocular swabs from cats showing symptoms of upper respiratory tract infection and FHV positivity detected by polymerase chain reaction (PCR). Viral isolation was carried out using feline kidney (F81) cell lines. Confirmation of FHV-1 presence was achieved through PCR detection, sequencing, electron microscopy, and indirect immunofluorescence assay. The isolated strains were further characterized by evaluating their titers, growth kinetics, and genetic characteristics. Additionally, we assessed the pathogenicity of the isolated strains in a feline model, monitoring clinical signs, viral shedding, and histopathological changes. (3) Results: Three strains of FHV-1 were isolated, purified, and identified. The isolated FHV-1 strains exhibited high homology among themselves and with domestic isolates and FHV-1 viruses from around the world. However, they showed varying degrees of virulence, with one strain (FHV-A1) causing severe clinical signs and histopathological lesions. (4) Conclusion: This study advances our understanding of the genetic and pathogenic characteristics of FHV-1 in China. These findings underscore FHV-A1 isolate as a potentially ideal candidate for establishing a challenge model and as a potential vaccine strain for vaccine development.

11.
Bioelectrochemistry ; 160: 108774, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38981325

RESUMO

Salivary α-amylase (α-ALS) has drawn attention as a possible bioindicator for dental caries. Herein, combining the synergistic properties of multi-walled carbon nanotubes (MWCNTs), ß-cyclodextrin (ß-CD) and starch, an electrochemical sensor is constructed employing ferrocene (FCN) as an electrochemical indicator to oversee the progression of the enzymatic catalysis of α-ALS. The method involves a two-step chemical reaction sequence on a screen-printed carbon electrode (SPCE). X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Field emission scanning electron microscope (FE-SEM), and Dynamic light scattering (DLS) were used to characterize the synthesized material, while Static water Contact angle measurements, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) were performed to monitor each step of sensor fabrication. The electrochemical sensor permitted to detect α-ALS within the linear range of 0.5-280 U mL-1, revealing detection (LOD), and quantification (LOQ) values of 0.041 U mL-1, and 0.159 U mL-1, respectively. Remarkably, the sensor demonstrated exceptional specificity and selectivity, effectively discriminating against other interfering substances in saliva. Validation of the method involved analyzing α-ALS levels in artificial saliva with an accuracy range of 97 % to 103 %, as well as in real clinical saliva samples across various age groups.


Assuntos
Técnicas Biossensoriais , Cárie Dentária , Técnicas Eletroquímicas , Nanotubos de Carbono , Amido , beta-Ciclodextrinas , beta-Ciclodextrinas/química , Humanos , Nanotubos de Carbono/química , Técnicas Biossensoriais/métodos , Amido/química , Técnicas Eletroquímicas/métodos , Cárie Dentária/diagnóstico , Saliva/química , Limite de Detecção , alfa-Amilases Salivares/análise , alfa-Amilases Salivares/metabolismo , Eletrodos
12.
Sheng Wu Gong Cheng Xue Bao ; 40(7): 2322-2332, 2024 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-39044594

RESUMO

This study aims to establish an ELISA method with high specificity for the detection of antibodies against Mycoplasma hyopneumoniae. Firstly, we constructed a recombinant strain Escherichia coli BL21(DE3)-pET-32a(+)-mhp336 to express the recombinant protein Mhp336 and used the purified Mhp336 as the coating antigen. Then, we optimized the ELISA parameters, including antigen concentration, blocking buffer, blocking time, dilution of serum, incubation time with serum, secondary antibody dilution, secondary antibody incubation time, colorimetric reaction time, and cut-off value. Afterwards, reproducibility experiments were conducted, and the cross reactivity of Mhp366 with other antisera of porcine major pathogens and the maximum dilution ratios of the sera were determined. Finally, 226 porcine serum samples were detected using the method established in this study, a commercial ELISA kit for M. hyopneumoniae antibody detection, and a convalescent serum ELISA kit for M. hyopneumoniae antibody detection. The detection results of the three methods were compared to evaluate the sensitivity and specificity of the ELISA method established in this study. For this method, the optimal antigen concentration, blocking buffer, blocking time, dilution of serum, incubation time with serum, secondary antibody dilution, secondary antibody incubation time, and colorimetric reaction time were 0.05 µg/mL, PBS containing 2.5% skim milk, 1 h, 1:500, 0.5 h, 1:10 000, 1 h, and 5 min, respectively. Validation of the ELISA method based on Mhp336 showed a cut-off value of 0.332. The coefficients of variation of both intra-batch and inter-batch kits were below 7%. The detection results of porcine serum samples indicated that the method established in this study outperformed the commercial ELISA kit and the convalescent serum ELISA kit for M. hyopneumoniae antibody detection in terms of sensitivity and specificity. We successfully established an ELISA method for detecting the antibodies against M. hyopneumoniae based on Mhp336 protein. This method demonstrated high sensitivity and specificity, serving as a tool for the prevention of mycoplasmal pneumonia of swine in pig farms.


Assuntos
Anticorpos Antibacterianos , Ensaio de Imunoadsorção Enzimática , Mycoplasma hyopneumoniae , Proteínas Recombinantes , Ensaio de Imunoadsorção Enzimática/métodos , Mycoplasma hyopneumoniae/imunologia , Animais , Suínos , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/genética , Anticorpos Antibacterianos/imunologia , Anticorpos Antibacterianos/sangue , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/imunologia , Pneumonia Suína Micoplasmática/imunologia , Pneumonia Suína Micoplasmática/diagnóstico , Pneumonia Suína Micoplasmática/microbiologia , Sensibilidade e Especificidade , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/genética
13.
Biosens Bioelectron ; 261: 116493, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38901393

RESUMO

Although circulating tumor cells (CTCs) have demonstrated considerable importance in liquid biopsy, their detection is limited by low concentrations and complex sample components. Herein, we developed a homogeneous, simple, and high-sensitivity strategy targeting breast cancer cells. This method was based on a non-immunological stepwise centrifugation preprocessing approach to isolate CTCs from whole blood. Precise quantification is achieved through the specific binding of aptamers to the overexpressed mucin 1 (MUC1) and human epidermal growth factor receptor 2 (HER2) proteins of breast cancer cells. Subsequently, DNAzyme cleavage and parallel catalytic hairpin assembly (CHA) reactions on the cholesterol-stacking DNA machine were initiated, which opened the hairpin structures T-Hg2+-T and C-Ag+-C, enabling multiple amplifications. This leads to the fluorescence signal reduction from Hg2+-specific carbon dots (CDs) and CdTe quantum dots (QDs) by released ions. This strategy demonstrated a detection performance with a limit of detection (LOD) of 3 cells/mL and a linear range of 5-100 cells/mL. 42 clinical samples have been validated, confirming their consistency with clinical imaging, pathology findings and the folate receptor (FR)-PCR kit results, exhibiting desirable specificity of 100% and sensitivity of 80.6%. These results highlight the promising applicability of our method for diagnosing and monitoring breast cancer.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Colesterol , DNA Catalítico , Células Neoplásicas Circulantes , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Neoplasias da Mama/sangue , Técnicas Biossensoriais/métodos , DNA Catalítico/química , Biópsia Líquida/métodos , Células Neoplásicas Circulantes/patologia , Colesterol/sangue , Colesterol/análise , Limite de Detecção , Pontos Quânticos/química , Receptor ErbB-2/análise , Mucina-1/análise , Mucina-1/sangue , Aptâmeros de Nucleotídeos/química , Linhagem Celular Tumoral , Telúrio/química , Compostos de Cádmio/química
14.
Indian J Med Microbiol ; 49: 100612, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38750966

RESUMO

OBJECTIVES: The objective of this investigation was to examine the mechanisms associated with antibiotic resistance in Stenotrophomonas maltophilia clinical isolates retrieved from hospitalized patients undergoing open heart surgery in a Heart Center located in Tehran, Iran. MATERIALS AND METHODS: This investigation encompassed a cross-sectional study of 60 S. maltophilia isolates, which were procured from diverse clinical specimens. Primary identification of the isolates was conducted through conventional microbiologic methods and subsequently verified by means of PCR primers. The E-test was utilized to establish the minimum inhibitory concentrations (MICs). PCR was then employed to ascertain the antibiotic resistance genes (sul1, sul2, Smqnr and intl1 - intl3). RESULTS: In this study, a total of sixty clinical isolates of S. maltophilia were collected, with the majority of them being obtained from Intensive Care Units (ICU) (n = 54; 90%). The disk diffusion method yielded results indicating that 55% of the isolates were sensitive to minocycline, whereas 30% were intermediate and 15% were found to be resistant. Additionally, the MIC results revealed that the resistant rates of the isolates towards ceftazidime, cotrimoxazole and levofloxacin were 46.7%, 1.7% and 5%, respectively. The PCR amplification of three classes of integrons genes indicated that fifteen (25%) of the isolates carried int1, while no detection for intl2 and intl3 was reported. Furthermore, the prevalence of antibiotic resistance genes (sul1, sul2, and Smqnr) was identified in 15 (25%), 6 (10%), and 28 (46.7%) isolates, respectively. CONCLUSION: The reported increasing rate of antibiotic resistance and mobile genetic elements that could extend the resistance genes to other strains in the hospital, finally it could be an alarming issue for healthcare settings that need special attention to this strain and the epidemiological study on this issue.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Infecções por Bactérias Gram-Negativas , Integrons , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Stenotrophomonas maltophilia , Humanos , Stenotrophomonas maltophilia/genética , Stenotrophomonas maltophilia/efeitos dos fármacos , Stenotrophomonas maltophilia/isolamento & purificação , Integrons/genética , Irã (Geográfico)/epidemiologia , Estudos Transversais , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Prevalência , Genes Bacterianos/genética , Proteínas de Bactérias/genética , Masculino
15.
J Nepal Health Res Counc ; 21(4): 636-641, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38616595

RESUMO

BACKGROUND: Coagulase Negative Staphylococci have been widely associated with medical device implant treatment and immune-compromised patients. Despite having increasing interest in Coagulase Negative Staphylococci, few studies from Nepal have reported the association of these organisms with urinary tract infections, conjunctivitis, high vaginal swabs, and cerebrospinal fluid. This study was carried out to determine antibiotic susceptibility pattern and biofilm production among Coagulase Negative Staphylococci isolated from clinical samples at tertiary care hospital. METHODS: This study was a hospital based cross-sectional study in which 3690 clinical samples were included. Isolation and identification of isolates was done following standard microbiological protocol. Coagulase Negative Staphylococci were identified phenotypically on the basis of gram staining, slide and tube coagulase test and by various sugar fermentation tests. Antibiotic susceptibility test was done following Kirby Bauer disk diffusion method (Clinical and Laboratory Standards Institute 2020). Biofilm production was determined by Tissue Culture Plate technique. RESULTS: A total of 113 isolates of Coagulase Negative Staphylococci were detected. Among them S. epidermidis (45.1%), S. saprophyticus (23.9%), S. haemolyticus (16.8%), S. hominis (5.3%), S. capitis (2.7%), -----S. cohini (1.8%), S. lugdunensis (1.8%) and S. sciuri (2.7%) were identified phenotypically. All isolates were found to be resistant against Ampicillin and 111 (98.2%) were sensitive against Linezolid.23.9% of CoNS were strong biofilm producers, 19.5% moderate and 56.6 % were non/weak biofilm producers. CONCLUSIONS: It requires susceptibility test for prescribing antibiotics against Coagulase Negative Staphylococci in hospital and the misuse of antibiotics should be prevented.


Assuntos
Coagulase , Staphylococcus , Feminino , Humanos , Estudos Transversais , Centros de Atenção Terciária , Nepal , Antibacterianos/farmacologia , Biofilmes
16.
Biosens Bioelectron ; 256: 116273, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621341

RESUMO

Simple and reliable profiling of tumor-derived exosomes (TDEs) holds significant promise for the early detection of cancer. Nonetheless, this remains challenging owing to the substantial heterogeneity and low concentration of TDEs. Herein, we devised an accurate and highly sensitive electrochemical sensing strategy for TDEs via simultaneously targeting exosomal mucin 1 (MUC1) and programmed cell death ligand 1 (PD-L1). This approach employs high-affinity aptamers as specific recognition elements, utilizes rolling circle amplification and DNA nanospheres as effective bridges and signal amplifiers, and leverages methylene blue (MB) and doxorubicin (DOX) as robust signal reporters. The crux of this separation- and label-free method is the specific response of MB and DOX to G-quadruplex structures and DNA nanospheres, respectively. Quantifying TDEs using this strategy enabled precise discrimination of lung cancer patients (n = 25) from healthy donors (n = 12), showing 100% specificity (12/12), 92% sensitivity (23/25), and an overall accuracy of 94.6% (35/37), with an area under the receiver operating characteristic curve (AUC) of 0.97. Furthermore, the assay results strongly correlated with findings from computerized tomography and pathological analyses. Our approach could facilitate the early diagnosis of lung cancer through TDEs-based liquid biopsy.


Assuntos
Aptâmeros de Nucleotídeos , Antígeno B7-H1 , Técnicas Biossensoriais , Doxorrubicina , Técnicas Eletroquímicas , Exossomos , Neoplasias Pulmonares , Humanos , Técnicas Biossensoriais/métodos , Exossomos/química , Técnicas Eletroquímicas/métodos , Neoplasias Pulmonares/química , Aptâmeros de Nucleotídeos/química , Doxorrubicina/química , DNA/química , Azul de Metileno/química , Nanosferas/química , Quadruplex G
17.
bioRxiv ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38659886

RESUMO

Cryptosporidium is a leading cause of severe diarrhea and mortality in young children and infants in Africa and southern Asia. More than twenty Cryptosporidium species infect humans, of which C. parvum and C. hominis are the major agents causing moderate to severe diarrhea. Relatively few genetic markers are typically applied to genotype and/or diagnose Cryptosporidium. Most infections produce limited oocysts making it difficult to perform whole genome sequencing (WGS) directly from stool samples. Hence, there is an immediate need to apply WGS strategies to 1) develop high-resolution genetic markers to genotype these parasites more precisely, 2) to investigate endemic regions and detect the prevalence of different genotypes, and the role of mixed infections in generating genetic diversity, and 3) to investigate zoonotic transmission and evolution. To understand Cryptosporidium global population genetic structure, we applied Capture Enrichment Sequencing (CES-Seq) using 74,973 RNA-based 120 nucleotide baits that cover ~92% of the genome of C. parvum. CES-Seq is sensitive and successfully sequenced Cryptosporidium genomic DNA diluted up to 0.005% in human stool DNA. It also resolved mixed strain infections and captured new species of Cryptosporidium directly from clinical/field samples to promote genome-wide phylogenomic analyses and prospective GWAS studies.

18.
Int Heart J ; 65(2): 329-338, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38556340

RESUMO

Hypertension and atherosclerosis often occur simultaneously. This study aimed to explore the role and mechanism of platelet microparticle (PMP) -derived microRNA-320b (miR-320b) in patients with hypertension accompanied by atherosclerosis.We collected samples from 13 controls without hypertension and atherosclerosis and 20 patients who had hypertension accompanied by atherosclerosis. In vitro, platelets were activated by Thrombin receptor-activating peptide to produce PMPs. HUVECs were induced by CoCl2 to mimic a hypoxic environment in vitro. RT-qPCR was employed to detect the expression levels of CD61, miR-320b, and ETFA. The protein expression level of ETFA was evaluated via Western blotting. Furthermore, 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide, 5-ethynyl-2'-deoxyuridine, and wound healing assays were employed to assess the proliferation and migration of HUVECs. Enzyme-linked immunosorbent assay was used to measure the oxidative stress and inflammation-related factor expression.The expression of miR-320b was reduced in both platelets and PMPs but increased in plasma. MiR-320b promoted CoCl2-induced HUVEC viability, proliferation, and migration. The levels of the oxidative stress factors SOD and GSH as well as the inflammatory factor IL-10 were elevated in the CoCl2 + miR-320b mimics group compared with both the CoCl2 + mimics NC and CoCl2 groups. Conversely, the levels of the oxidative stress factors MDA and ROS as well as the inflammatory factors IL-6, TNF-α, and IL-1ß were decreased. These results were regulated by miR-320b targeting ETFA.PMP-derived miR-320b inhibits the development of hypertension accompanied by atherosclerosis by targeting ETFA.


Assuntos
Aterosclerose , Hipertensão , MicroRNAs , Humanos , Apoptose , Aterosclerose/genética , Cobalto , Flavoproteínas Transferidoras de Elétrons , Hipertensão/complicações , Hipertensão/genética , MicroRNAs/metabolismo
19.
ACS Nano ; 18(14): 9958-9968, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38547522

RESUMO

Single-molecule fluorescence in situ hybridization (smFISH) represents a promising approach for the quantitative analysis of nucleic acid biomarkers in clinical tissue samples. However, low signal intensity and high background noise are complications that arise from diagnostic pathology when performed with smFISH-based RNA imaging in formalin-fixed paraffin-embedded (FFPE) tissue specimens. Moreover, the associated complex procedures can produce uncertain results and poor image quality. Herein, by combining the high specificity of split DNA probes with the high signal readout of ZnCdSe/ZnS quantum dot (QD) labeling, we introduce QD split-FISH, a high-brightness smFISH technology, to quantify the expression of mRNA in both cell lines and clinical FFPE tissue samples of breast cancer and lung squamous carcinoma. Owing to its high signal-to-noise ratio, QD split-FISH is a fast, inexpensive, and sensitive method for quantifying mRNA expression in FFPE tumor tissues, making it suitable for biomarker imaging and diagnostic pathology.


Assuntos
Neoplasias da Mama , Pontos Quânticos , Humanos , Feminino , RNA/análise , Inclusão em Parafina , Hibridização in Situ Fluorescente/métodos , RNA Mensageiro/genética , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Formaldeído
20.
Pathogens ; 13(3)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38535580

RESUMO

Gallibacterium anatis, recognized as a resident and opportunistic pathogen primarily in poultry, underwent investigation in unwell domestic mammals and birds. The study encompassed the mapping and comparison of G. anatis isolates, evaluation of their genetic diversity, and determination of their susceptibility to antimicrobials. A total of 11,908 clinical samples were analyzed using cultivation methods and MALDI-TOF. Whole-genome sequencing was performed on seven calf isolates and six hen isolates. Among mammals, G. anatis was exclusively detected in 22 young dairy calves, while among domestic birds, it was found in 35 individuals belonging to four species. Pathological observations in calves were predominantly localized in the digestive tract, whereas in birds, multi-organ infections and respiratory system infections were most prevalent. Distinct groups of genes were identified solely in calf isolates, and conversely, those unique to hen isolates were also recognized. Novel alleles in the multilocus sequence typing scheme genes and previously unidentified sequence types were observed in both calf and hen isolates. Antimicrobial susceptibility exhibited variation between bird and calf isolates. Notably, G. anatis isolates from calves exhibited disparities in genotype and phenotype compared to those from hens. Despite these distinctions, G. anatis isolates demonstrated the capability to induce septicemia in both species.

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