New Microbiologica最新文献

As a rare opportunistic pathogen of Gram-positive bacillus, Nocardia is capable of entering the human body through the respiratory tract and wounds, leading to disseminated infections in the lungs, skin, or systemically. The majority of patients infected with Nocardia exhibit defective or suppressed immune function. Herein, in this report, we present a case of systemic lupus erythematosus (SLE) complicated by a central nervous system infection caused by Nocardia nova. Specifically, a female patient was admitted to our hospital for treatment with a three-day history of headache, nausea, and vomiting, and was diagnosed with purulent meningitis caused by Nocardia nova after culture of her cerebrospinal fluid (CSF). Based on the characteristics of Nocardia nova and the results of the drug sensitivity test, we developed a clinical treatment plan, which led to the successful discharge of the patient. As research progresses, an increasing number of reports on infections caused by Nocardia are being released. The purpose of reporting this case is to provide a reference for both laboratory identification and clinical treatment.

Microbiota research has rapidly emerged as a pivotal field, with over 250,000 publications and more than ten million citations recorded in the Web of Science Core Collection database by 2024. There were 1682 original microbiota citation classics (each receiving 400 citations or more) identified over the past three decades, totaling 1,559,594 citations and averaging 927 citations per paper. Collaborative efforts in the production of these citation classics involved 87 out of 89 participating countries and 2107 out of 2142 institutions. The USA, various European countries, and China emerged as the leading contributors to this burgeoning research area. Jeffrey I. Gordon, Rob Knight, and Curtis Huttenhower were the prominent figures in microbiota research. Author keywords were analyzed, which revealed a notable shift in research focus from environmental microorganisms to human gut microbiota. Advances such as high-throughput 16S rRNA sequencing and metagenomics expanded the scope of investigations into host-microbiota interactions. Current research interests encompass exploring mechanisms underlying gut-X-axis conditions, including inflammatory bowel disease, obesity, diabetes, colorectal cancer, liver diseases, and neurological disorders. Moreover, environmental exposures have been evidenced to alter gut microbiota and metabolites, contributing a novel research direction. Future research direction is also anticipated to delve further into biosynthetic gene engineering technologies aimed at microbial interventions, including probiotics and fecal microbiota transplantation. This study outlines the evolving landscape of microbiota research and provides valuable insights to inform future investigations within the field.

Biological green synthesis of silver nanoparticles (AgNPs) offers potent antimicrobial properties and provides a promising approach against drug-resistant microbes. The present study aims to synthesize AgNPs using Mung bean (Vigna radiate) aqueous extract and the probiotic Bacillus clausii, and to evaluate their antibacterial activity individually and in combination against several bacterial strains. Synthesized AgNPs were characterized by ultraviolet-visible spectroscopy (UV-vis) and scanning electron microscopy (SEM). V. radiata AgNPs were revealed at 450 nm, with spherical to oval shapes ranging in size from 15.9 to 23.0 nm; probiotic AgNPs were observed at 425 nm, also with a spherical shape ranging in size from 16.4 to 23.7 nm. The antibacterial assay was performed using the agar well diffusion method against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli. Results indicated that V. radiata aqueous extract and the probiotic solution did not exhibit any effect, whereas synthesized V. radiata and probiotic AgNPs showed antibacterial activity against all tested bacteria. AgNPs possessed higher antibacterial activity than individual AgNPs when used in combination against almost all bacteria studied. Therefore, it is suggested that using natural antimicrobial agents to synthesize NPs could serve as an eco-friendly alternative to antibiotics.

In the modern ART era, long-term treatment success should be understood as a combination of HIVRNA suppression and a person-centered approach, based on individual therapeutic history, GRT, past toxicities, and comorbidities. The pharmacological determinants of long-term virological suppression are potency, high-genetic barrier, and high-forgiveness regimen. Interplays and relative weights of these three factors can vary according to the different stages of treatment.

The present study aimed to determine the resistance mechanisms and clonal relationships among vancomycin-resistant Enterococci (VRE) isolated in AHEPA University Hospital during the pandemic year 2021. Overall, 140 clinical VRE were isolated during the study period and 44 were randomly selected for molecular analysis. A multiplex PCR was employed to detect vancomycin resistance genes (vanA, vanB, vanC, vanD, vanE, vanG) using specific primers. Additionally, pulsed-field gel electrophoresis (PFGE) was performed to assess the clonal relatedness of the selected isolates. The multiplex PCR showed that 36 of the 44 studied strains (81.9%) harbored the vanA gene whereas, 7 of 44 (15.9%) co-harbored the vanA and vanB resistance genes; one isolate had a negative PCR result. PFGE analysis unveiled 37 distinct electrophoretic patterns among the 44 VRE isolates with a similarity threshold of 75%. These patterns were clustered into 4 distinct branches. Our findings indicate a polyclonal distribution of vanA genes among the studied isolates and the notable concomitant presence of vanA/vanB genotypes. Furthermore, these results highlight the worsening that took place during the COVID-19 pandemic period regarding antibiotic resistance rates, underscoring the imperative need for stringent infection control measures and active surveillance.

Candida glabrata can exhibit resistance or reduced susceptibility to fluconazole, and there is an increasing frequency of resistance to echinocandins. Candida nivariensis and Candida bracarensis, newly described in 2005 and 2006, respectively, belong to the C. glabrata complex along with C. glabrata sensu stricto. C. nivariensis and C. bracarensis have been shown to exhibit higher resistance and virulence compared to C. glabrata sensu stricto. These three species cannot be reliably distinguished based on phenotypic characteristics or biochemical-based identification systems. In this study, 40 strains initially identified as C. glabrata using biochemical-based systems were re-identified to the species level through ITS region sequencing. Antifungal susceptibility testing was conducted using the Sensititre YeastOne susceptibility panel. All strains were identified as C. glabrata sensu stricto and showed dose-dependent susceptibility to fluconazole. Of the 40 strains, 39 (97.5%) were susceptible to caspofungin, anidulafungin, and micafungin, while one (2.5%) was resistant. Further research is needed on the epidemiology, virulence factors, and resistance profiles of C. nivariensis and C. bracarensis. Accurate species-level identification and antifungal susceptibility testing of C. glabrata complex isolates are significant.

A 66-year-old female, a known case of endometrial serous carcinoma, presented with a history of poor oral intake. Elevated C-reactive protein was identified, and an echocardiogram showed evidence of large circumferential pericardial fluid with maximum diameter measuring 4.4 cm. Further analysis of the pericardial fluid revealed growth of Candida krusei. Treatment was initiated with caspofungin 150mg intravenously once daily for 28 days, followed by oral maintenance therapy with voriconazole for 10 days. No relapse or re-infection was observed during 10 days of follow-up. A literature search was performed, which demonstrated that Candida albicans is the most encountered Candida spp. associated with acute pericarditis. Additionally, the following risk factors were observed, including history of major surgery, COVID-19 infection, and use of broad-spectrum antibiotics. This article presents a unique case of acute pericarditis caused by C. krusei. It highlights the importance of identifying the etiology in immunocompromised cohorts and emphasizes the role of establishing formative treatment guidelines for the management of Candida spp. pericarditis.

The aim of this retrospective study was to investigate the molecular characteristics and survival ability of clinical isolates of extended-spectrum β-lactamase (ESBL)-producing strains of Klebsiella pneumoniae (K. pneumoniae) in a hospital setting. ESBL-producing K. pneumoniae clinical isolates were collected from hospitalized patients at the University Clinical Hospital of Mostar, Bosnia and Herzegovina. Identification and antibiotic susceptibility tests were performed according to established laboratory methods and Clinical and Laboratory Standards Institute standards. Phenotypic identification of the isolates was confirmed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Minimum inhibitory concentrations were determined using the Vitek® 2 Compact System. Clonal relationships between the different isolates were studied using pulsed-field gel electrophoresis. Molecular characterization of ESBL-coding genes was performed using multiplex polymerase chain reaction. The survival and pellicle formation abilities of ESBL-producing K. pneumoniae isolates were also investigated. Among 471 isolated K. pneumoniae strains, 149 isolates (31.6%) were ESBL-producing. The bla genes encoding CTX-M-1-group ESBLs were identified in almost all isolates, with the majority carrying blaCTX-M-15. Two isolates contained blaCTX-M-3. All isolates carried blaTEM-1. The blaSHV genes identified were blaSHV-1, blaSHV-5, blaSHV-11, and blaSHV-28. Six isolates harbored blaOXA-1. ESBL-producing K. pneumoniae strains survived on dry cotton for up to 49 days.

This review outlines the progress and challenges in HIV cure research, with a particular focus on gene therapy, latency-reversing agents (LRAs), immunotherapy, and stem cell transplants. The objective of these advances is to achieve either a sterilizing or a functional cure, whereby the virus is either eradicated or controlled without the need for ongoing treatment. Gene editing tools, such as CRISPR-Cas9, have demonstrated the potential to remove HIV DNA from cells. LRAs, on the other hand, aim to reactivate latent virus, thereby rendering it susceptible to treatment or immune clearance. Immunotherapy, including therapeutic vaccines and broadly neutralizing antibodies, aims to enhance the immune response to HIV. However, achieving long-term suppression without antiretroviral therapy remains a significant challenge. Stem cell transplants have resulted in instances of remission; however, the methodology is intricate, perilous, and viable solely for patients with particular medical requirements. Each approach encounters challenges pertaining to safety, administration, and accessibility. In sum, while considerable advancement has been achieved, a combination of therapeutic strategies and further innovations are imperative for the development of a sustainable, widely accessible HIV cure.

Hepatitis E is generally considered a mild disease, but severe cases are also observed. In high-income countries, most hepatitis E cases are due to HEV genotype 3 and are linked mainly to the consumption of pork or wild boar meat, but data on the correlation of viral variants and hepatitis severity are still preliminary. We described a serious acute hepatitis E (Genotype 3e) case observed in the city of Rieti (Lazio region, Italy), and compared it with previous cases found in the same geographical area. Phylogenetic analysis of open reading frame 2 (ORF2) showed that the HEV strain of the patient in Rieti is closely related to those identified in the acute HEV hepatitis outbreak in 2019. Our data suggest the need to strengthen surveillance and prevention against HEV infection and investigation of pathogenicity linked to specific HEV variants.