Microbiology Research

9 pages, 2777 KiB

Open AccessCommunication

Comparison of Antibody Persistence up to 6 Months after Additional Booster Vaccination with ChAdOx1 nCoV-19 Vaccine

by Pawita Suwanwattana, May Han, Tanawin Nopsopon, Phanupong Phutrakool, Chatpol Samuthpongtorn, Wannarat Pongpirul, Wisit Prasithsirikul and Krit Pongpirul

Microbiol. Res. 2023, 14(2), 810-818; https://doi.org/10.3390/microbiolres14020057 - 16 Jun 2023

Viewed by 2018

Abstract

Vaccines are crucial for controlling the COVID-19 pandemic, and booster doses are becoming increasingly important. This study aimed to assess the efficacy of the ChAdOx1 nCoV-19 vaccine from AstraZeneca as a third dose in healthcare workers at different time intervals (one, three, and [...] Read more.

Vaccines are crucial for controlling the COVID-19 pandemic, and booster doses are becoming increasingly important. This study aimed to assess the efficacy of the ChAdOx1 nCoV-19 vaccine from AstraZeneca as a third dose in healthcare workers at different time intervals (one, three, and six months). Two methods to measure immune response—ELISA (EUROIMMUN Medizinische Labordiagnostika AG, Luebeck, Germany) and ELISpot (Mabtech AB, Macka Strand, Sweden)—were used. A total of 170 participants were included in the study. The results showed that while IgG levels decreased at six months compared to levels at one and three months, they were still significantly higher than the baseline. Furthermore, neutralizing levels at three and six months and after the third dose were not significantly different. These findings suggest that the immune response induced by the vaccine was robust and effective for several months. These results have significant implications for public health policymakers, as they provide strong support for booster vaccinations. The ChAdOx1 nCoV-19 vaccine appears to be a reliable option for preventing the spread of COVID-19, and this study provides valuable information for healthcare workers and policymakers in managing the pandemic. Full article

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12 pages, 4629 KiB

Open AccessArticle

Cryptococcus gattii Can Use the Cactus Pilosocereus spp. to Grow and Develop a Capsule and Produce Melanin In Vitro

by Paola Ramos-Irizarry, Bárbara Sánchez and Yaliz Loperena-Álvarez

Microbiol. Res. 2023, 14(2), 798-809; https://doi.org/10.3390/microbiolres14020056 - 13 Jun 2023

Cited by 1 | Viewed by 2425

Abstract

Cryptococcus gattii is a pathogenic yeast, member of the C. neoformans/gattii complex. Previous work from our laboratory has established the presence of C. gattii on cacti lesions, providing proof that it can grow in a stressful environment. However, it is not known which [...] Read more.

Cryptococcus gattii is a pathogenic yeast, member of the C. neoformans/gattii complex. Previous work from our laboratory has established the presence of C. gattii on cacti lesions, providing proof that it can grow in a stressful environment. However, it is not known which part of the cactus the yeast uses for nutrients. The purpose of this research is to determine the ability of C. gattii to grow in different parts of the cactus to assess how the yeast adapts to grow in this unique environment. Cactus media were developed using the outer, inner, and whole cactus from Pilosocereus spp. Cryptcoccus gattii was grown on the different cactus media, along with potato dextrose agar as a control for 24 and 48 h at 30 °C. Compared to the control medium, yeast growth was reduced in all cactus media, while an increase in the capsule development of the yeast grown in the inner part and the whole-cactus media was observed. Interestingly, the yeast produces melanin when grown in the outer membrane medium, which was dependent on laccase, suggesting that the outer membrane may contain a precursor that stimulatates pigment production. To our knowledge, this is the first study addressing these key differences in the growth of C. gattii on different parts of the cactus. Full article

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11 pages, 2885 KiB

Open AccessCommunication

Potassium-Incorporated Titanium Oxide Nanoparticles Modulate Human Dendritic Cell Immune Response to Mycobacterium leprae

by Sam Warren, So Yoon Lee, Jose Barragan, Piya Kositangool, Hatsuko Yoshikubo and Jorge Cervantes

Microbiol. Res. 2023, 14(2), 787-797; https://doi.org/10.3390/microbiolres14020055 - 13 Jun 2023

Viewed by 1750

Abstract

The two polar clinical forms of leprosy, termed tuberculoid and lepromatous, have polarized cellular immune responses with complex immunological distinctions. The predominance of DCs in tuberculoid leprosy has been reported, while the lepromatous pattern of illness is associated with weak activation of local [...] Read more.

The two polar clinical forms of leprosy, termed tuberculoid and lepromatous, have polarized cellular immune responses with complex immunological distinctions. The predominance of DCs in tuberculoid leprosy has been reported, while the lepromatous pattern of illness is associated with weak activation of local populations of DCs. TiO₂ nanoparticles have previously been shown to induce maturation of these cells, leading to an inflammatory response similar to adjuvant usage in vaccine administration. We aimed to evaluate the effect of potassium-incorporated Ti oxide nanostructures, namely KTiO_xs, in the response of human monocyte-derived DCs to live M. leprae. Human monocytic cell line dual THP-1, which harbors two inducible reporter plasmid systems for transcription factor activation of NF-κB and interferon regulating factor (IRF), was treated with titanium control or with 1 mol/L KOH-treated Ti or 10 mol/L KOH for 24 h. Subsequently, cells were infected with M. leprae. KTiO_x nanoparticles increase DC phagocytic activity without inflammation. KTiO_x exposure of DCs led to an increase in IRF activation with modulation of the inflammatory response to live M. leprae. It also led to differential secretion of the critical components of innate immune response and the development of cell-mediated immunity against intracellular pathogens. This study demonstrates the effect of nanostructures of KTiO_xs and the usefulness of nanoparticle technology in the in vitro activation of human DCs against an infectious disease with a puzzling immune spectrum. Our findings may prompt future therapeutic strategies, such as DC immunotherapy for disseminated and progressive lepromatous lesions. Full article

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32 pages, 9502 KiB

Open AccessArticle

Lichens from the Roosevelt River Area in the Brazilian Amazon

by André Aptroot

Microbiol. Res. 2023, 14(2), 755-786; https://doi.org/10.3390/microbiolres14020054 - 8 Jun 2023

Cited by 3 | Viewed by 1991

Abstract

Lichens were investigated in Brazil in a small area along the Roosevelt River in Amazonas; 25 species are first reports for Brazil, and 190 additional species are first records for Amazonas state. As many as 24 species are described that are new to [...] Read more.

Lichens were investigated in Brazil in a small area along the Roosevelt River in Amazonas; 25 species are first reports for Brazil, and 190 additional species are first records for Amazonas state. As many as 24 species are described that are new to science: Allographa lineatipruinosa, Allographa variopruinata, Arthonia xanthopycnidiata, Astrothelium aurantioseptemseptatum, Astrothelium bulbosum, Astrothelium coloratum, Astrothelium inspersonovemseptatum, Astrothelium insulare, Astrothelium laureroides, Astrothelium marjoleinae, Astrothelium meandratum, Astrothelium multireflexum, Astrothelium myopicum, Astrothelium parabathelium, Astrothelium stellare (also known from Mato Grosso state), Astrothelium suprainspersum, Astrothelium xanthocavatum, Ocellularia fuscolichexanthonica, Ocellularia lichexanthocavata, Pertusaria amazonica, Phaeographis xantholirellinata, Porina ramiisidiata, Pseudopyrenula connexa, and Sprucidea squamulosa. Full article

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14 pages, 2714 KiB

Open AccessArticle

Relevance of the Microbiota on Ocular Diseases: A Bibliometric and Citation Network Analysis

by Miguel Angel Sanchez-Tena, Beatriz G. Galvez, Clara Martinez-Perez and Cristina Alvarez-Peregrina

Microbiol. Res. 2023, 14(2), 741-754; https://doi.org/10.3390/microbiolres14020053 - 6 Jun 2023

Viewed by 1829

Abstract

Background: This study aimed to analyze the relevance of different publications about microbiota on ocular diseases and their authors through a citation network analysis. In addition, the different research areas and the most cited publications have been identified. Methods: The bibliographic search was [...] Read more.

Background: This study aimed to analyze the relevance of different publications about microbiota on ocular diseases and their authors through a citation network analysis. In addition, the different research areas and the most cited publications have been identified. Methods: The bibliographic search was carried out through the Web of Science (WOS) database, using the following search term: “microbiota AND (vision OR eye OR visual)” for the period between 1995 and December 2022. The Citation Network Explorer and the CiteSpace software have been used to analyze the different publications. Results: 705 publications were found in the field of microbiota on ocular diseases, together with 1014 citation networks. The year 2022 was the year with more publications. The first authors with the highest number of publications in the microbiota on the ocular surface field were Chisari G, Chisari CG, and Li Y. This field is multidisciplinary, highlighting “microbiology” and “ophthalmology” as the main research areas. Publications were clustered into three main groups allowing the identification of the main research topics in this field. The principal was the composition and diversity of the bacterial community on the ocular surface of patients with several pathologies. Conclusion: It could be useful for researchers to choose suitable collaborators or projects to promote their research on the role of microbiota on ocular diseases, as well as to know the main research topics that are of major interest today. Full article

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14 pages, 7064 KiB

Open AccessReview

Antimicrobial Resistance and Antimicrobial Stewardship: Before, during and after the COVID-19 Pandemic

by Omar Khaznadar, Farah Khaznadar, Ana Petrovic, Lucija Kuna, Ana Loncar, Tea Omanovic Kolaric, Vjera Mihaljevic, Ashraf A. Tabll, Robert Smolic and Martina Smolic

Microbiol. Res. 2023, 14(2), 727-740; https://doi.org/10.3390/microbiolres14020052 - 31 May 2023

Cited by 7 | Viewed by 3806

Abstract

Antimicrobial resistance (AMR) is an ongoing phenomenon. It is a significant public health issue that has existed long before the coronavirus disease of 2019 (COVID-19) pandemic. It develops as microorganisms undergo genetic mutations that allow them to survive despite antimicrobial treatment. This process [...] Read more.

Antimicrobial resistance (AMR) is an ongoing phenomenon. It is a significant public health issue that has existed long before the coronavirus disease of 2019 (COVID-19) pandemic. It develops as microorganisms undergo genetic mutations that allow them to survive despite antimicrobial treatment. This process is highly associated with excessive and often unnecessary antimicrobial pharmacotherapy, which was often discussed during the COVID-19 pandemic. This article explores how the pandemic has affected antimicrobial stewardship by shifting the focus away from antimicrobial resistance, as well as the impact of enhanced antibiotic usage and measures such as lockdowns, mandatory testing and vaccination on antimicrobial resistance. Although these measures were regarded as successful in terms of limiting the pandemic, they have significantly contributed to an already escalating AMR issue. Outpatient methods in primary care and intensive care units aiming to prevent severe COVID-19 disease have contributed to the spread of multidrug-resistant bacteria, while laboratories burdened with COVID-19 testing have indirectly interrupted the detection of these bacteria. In this review, we summarize the pathogens whose AMRe has been greatly affected by COVID-19 measures and emphasize the importance of efficient antimicrobial stewardship in future pandemic and non-pandemic states to promote the responsible use of antibiotics and minimize AMR. Full article

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13 pages, 1778 KiB

Open AccessArticle

Public Health Importance of Preventive Measures for Salmonella Tennessee and Salmonella Typhimurium Strain LT2 Biofilms

by Simen Asefaw, Sadiye Aras, Md Niamul Kabir, Sabrina Wadood, Shahid Chowdhury and Aliyar Cyrus Fouladkhah

Microbiol. Res. 2023, 14(2), 714-726; https://doi.org/10.3390/microbiolres14020051 - 28 May 2023

Cited by 2 | Viewed by 2554

Abstract

Various serovars of Salmonella had been the subject of research for over 150 years; nonetheless, the bacterium has remained an important pathogen of public health concern to date. The tremendous ability of Salmonella to form biofilms on biotic and abiotic surfaces is an [...] Read more.

Various serovars of Salmonella had been the subject of research for over 150 years; nonetheless, the bacterium has remained an important pathogen of public health concern to date. The tremendous ability of Salmonella to form biofilms on biotic and abiotic surfaces is an important underlying reason for the prevalence of this opportunistic pathogen in healthcare, manufacturing, and the food chain. The current study illustrates that using very common industrial antimicrobial treatments at the highest concentrations suggested by the manufacturers is only efficacious against planktonic and one-day mature biofilms of the pathogen while exhibiting a lack of efficacy for complete removal of bacterial biofilms formed for longer than 2 days. This exhibits the importance of preventive measures against Salmonella biofilm formation in healthcare and manufacturing facilities, schools, nursing homes, and domestic environments. Additionally, our study illustrates the importance of including both planktonic and sessile cells of the pathogen in microbiology validation studies, especially for niche and hard-to-reach surfaces. The current study additionally investigated the suitability of an avirulent strain of the pathogen as a surrogate for pathogenic Salmonella serovars for public health microbiology validation studies when the use of virulent strains is not economically feasible or not possible due to safety concerns. Full article

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10 pages, 269 KiB

Open AccessCommunication

Factors Associated with Viral Load Suppression and Indicators of Stigma among People Living with HIV in Dar es Salaam Tertiary Hospitals, Tanzania

by Mary Spicar Kilapilo, Idda Hubert Mosha, George Msema Bwire, Godfrey Leonard Sambayi, Raphael Zozimus Sangeda and Japhet Killewo

Microbiol. Res. 2023, 14(2), 704-713; https://doi.org/10.3390/microbiolres14020050 - 24 May 2023

Viewed by 2666

Abstract

The perception of stigma can contribute to virological failure among people living with HIV (PLHIV). This study was conducted to find out how stigmatization and self-stigma affect the ability of people living with HIV (PLHIV) in Dar es Salaam, Tanzania, to keep their [...] Read more.

The perception of stigma can contribute to virological failure among people living with HIV (PLHIV). This study was conducted to find out how stigmatization and self-stigma affect the ability of people living with HIV (PLHIV) in Dar es Salaam, Tanzania, to keep their viral load down. This was a hospital-based cross-sectional study conducted in Temeke Regional Referral Hospital (RRH) and Amana RRH at the Care and Treatment Clinic (CTC) between July and August 2020 using a structured questionnaire with open- and close-ended questions. Multivariate logistic regression analysis was used to examine the factors of viral load suppression. The Chi-square test was used to compare the factors of stigmatization and viral load suppression. Altogether, 406 PLHIV participated, with the most being female respondents, 298 (73.2%). The majority (50%) were aged between 25 and 44 years, whereas 171 (42.5%) respondents were married. Most of the participants, 382 (94.6%), were on a dolutegravir-based regimen, with the majority, 215 (52.8%), having a refill interval of three months. Most respondents, 379 (93.1%), disclosed their status. Most participants, 355 (87.4%), preferred having a separate HIV clinic, while 130 (32.1%) participants were not ready to be attended by the health care workers (HCWs) familiar to them. Male patients were 60% less likely to suppress their viral load as compared to female patients (adjusted odds ratio [aOR]: 0.4, 95% confidence interval [95%]: 0.19–0.77, p-value = 0.007). The refill interval was significantly associated with viral load suppression. For example, patients with a one-month refill interval had odds of 0.01 (95% CI: 0.003–0.42, p-value = 0.0001) compared to six-month refill intervals. Stigmatization elements appeared to influence viral load suppression among PLHIV in the Dar es Salaam area, significantly predicting viral load outcomes when gender and time between refills were considered. Full article

15 pages, 649 KiB

Open AccessReview

Bacterial Bioprotectants: Biocontrol Traits and Induced Resistance to Phytopathogens

by Dilfuza Egamberdieva, Farkhod Eshboev, Oybek Shukurov, Burak Alaylar and Naveen Kumar Arora

Microbiol. Res. 2023, 14(2), 689-703; https://doi.org/10.3390/microbiolres14020049 - 22 May 2023

Cited by 9 | Viewed by 3857

Abstract

Plant growth and nutrition are adversely affected by various factors such as water stress, high temperature, and plant pathogens. Plant-associated microbes play a vital role in the growth and development of their hosts under biotic and abiotic stresses. The use of a rhizosphere [...] Read more.

Plant growth and nutrition are adversely affected by various factors such as water stress, high temperature, and plant pathogens. Plant-associated microbes play a vital role in the growth and development of their hosts under biotic and abiotic stresses. The use of a rhizosphere microbiome for plant growth stimulation and the biological control of fungal disease can lead to improved crop productivity. Mechanisms used by plant-growth-promoting rhizobacteria (PGPR) to protect plants from soilborne pathogens include antibiosis, the production of lytic enzymes, indole-3 acetic acid production, decreasing ethylene levels by secreting 1-aminocyclopropane-1-carboxylate deaminase, competition for nutrients and niches, parasitism and induced systemic resistance. In this review, we emphasize the biological control of plant pathogens by root-associated microbes and discuss traits involved in pathogen reduction. Future research should focus on the effect of root exudation on plant–pathogen interactions under various abiotic factors. Moreover, the development of microbial fungicides with longer shelf lives will help farmers to opt for organic agriculture, reducing the use of chemical fertilizers. This trend is expected to drive the adoption of biological control methods in agriculture. The future prospects for the biological control of plant diseases are bright and are expected to play an increasingly important role in sustainable agriculture. Full article

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16 pages, 1065 KiB

Open AccessReview

Radiation Impacts Microbiota Compositions That Activate Transforming Growth Factor-Beta Expression in the Small Intestine

by Irene Maier

Microbiol. Res. 2023, 14(2), 673-688; https://doi.org/10.3390/microbiolres14020048 - 19 May 2023

Viewed by 2284

Abstract

The composition of the gut microbiota represents an early indicator of chronic post-radiation outcomes in elderly bone and gastrointestinal homeostasis. Fecal microbiota analyses revealed that the relative abundances of Bacteroides massiliensis, Muribaculum sp., or Prevotella denticola were different between conventional microbiota (CM) [...] Read more.

The composition of the gut microbiota represents an early indicator of chronic post-radiation outcomes in elderly bone and gastrointestinal homeostasis. Fecal microbiota analyses revealed that the relative abundances of Bacteroides massiliensis, Muribaculum sp., or Prevotella denticola were different between conventional microbiota (CM) and anti-inflammatory restricted microbiota (RM). The murine RM was found conditional on mucosa-associated dysbiosis under both, disturbances of interleukin (IL)-17 signaling and exposure to radiation alone. This review discusses the hypothesis that intestinal microbiota induced alterations in DNA repair and expressed transforming growth factor (TGF)-β in the small intestine, thereby impacting bone microstructure and osteoblast dysfunction in silicon ion (1.5 Gy ²⁸Si ions of 850 MeV/u) irradiated mice. Bacterial microbiota compositions influenced therapeutic approaches, correlated with clinical outcomes in radiotherapy and were associated with alterations of the immune response to severe acute respiratory syndrome coronavirus (SARS-CoV)-2 infections during the last global pandemics. In the absence of TGF-β, functional metagenomics, cytokine profiles, bacterial community analyses in human and murine mucosa cells, and inflammatory markers in rat intestines were analyzed. This research finally showed radiation-induced osteolytic damage to correlated with specific features of intestinal bacterial composition, and these relationships were expatiated together with radiation effects on normal tissue cell proliferation. Full article

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17 pages, 4930 KiB

Open AccessArticle

Omics of an Enigmatic Marine Amoeba Uncovers Unprecedented Gene Trafficking from Giant Viruses and Provides Insights into Its Complex Life Cycle

by Yonas I. Tekle, Hanh Tran, Fang Wang, Mandakini Singla and Isimeme Udu

Microbiol. Res. 2023, 14(2), 656-672; https://doi.org/10.3390/microbiolres14020047 - 18 May 2023

Cited by 1 | Viewed by 2392

Abstract

Amoebozoa include lineages of diverse ecology, behavior, and morphology. They are assumed to encompass members with the largest genome sizes of all living things, yet genomic studies in the group are limited. Trichosphaerium, a polymorphic, multinucleate, marine amoeba with a complicated life [...] Read more.

Amoebozoa include lineages of diverse ecology, behavior, and morphology. They are assumed to encompass members with the largest genome sizes of all living things, yet genomic studies in the group are limited. Trichosphaerium, a polymorphic, multinucleate, marine amoeba with a complicated life cycle, has puzzled experts for over a century. In an effort to explore the genomic diversity and investigate extraordinary behavior observed among the Amoebozoa, we used integrated omics approaches to study this enigmatic marine amoeba. Omics data, including single-cell transcriptomics and cytological data, demonstrate that Trichosphaerium sp. possesses the complete meiosis toolkit genes. These genes are expressed in life stages of the amoeba including medium and large cells. The life cycle of Trichosphaerium sp. involves asexual processes via binary fission and multiple fragmentation of giant cells, as well as sexual-like processes involving genes implicated in sexual reproduction and polyploidization. These findings are in stark contrast to a life cycle previously reported for this amoeba. Despite the extreme morphological plasticity observed in Trichosphaerium, our genomic data showed that populations maintain a species-level intragenomic variation. A draft genome of Trichosphaerium indicates elevated lateral gene transfer (LGT) from bacteria and giant viruses. Gene trafficking in Trichosphaerium is the highest within Amoebozoa and among the highest in microbial eukaryotes. Full article

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10 pages, 506 KiB

Open AccessArticle

Use of Oral Corticosteroids to Treat HTLV-1-Associated Myelopathy (HAM) in São Paulo, Brazil

by Flavia Esper Dahy, Tatiane Assone, Rosa M. N. Marcusso, João V. Luisi de Moura, Michel E. J. Haziot, Jose E. Vidal, Jerusa Smid, Augusto C. Penalva de Oliveira and Jorge Casseb

Microbiol. Res. 2023, 14(2), 646-655; https://doi.org/10.3390/microbiolres14020046 - 11 May 2023

Viewed by 1713

Abstract

Background: During the development of human T-cell lymphotropic virus (HTLV-1)-associated myelopathy (HAM), the inflammatory phenomenon is very prominent and is a major factor in the outcome of the disease. The use of corticosteroids can modify their natural history, and in this study, we [...] Read more.

Background: During the development of human T-cell lymphotropic virus (HTLV-1)-associated myelopathy (HAM), the inflammatory phenomenon is very prominent and is a major factor in the outcome of the disease. The use of corticosteroids can modify their natural history, and in this study, we evaluated the effectiveness of using daily low-dose prednisone. Methods: This was a cross-sectional study using data collected by physicians monitoring patients with HAM at the Institute of Infectious Diseases “Emilio Ribas”, the main referral center for patients with infectious diseases in São Paulo, Brazil. The objective was to determine if daily low-dose oral prednisone would be able to stabilize the progression of HAM. The outcome measure was a change in the Osame Motor Disability Score (OMDS). Results: Fifty-four patients used treatment with oral prednisone, 5 milligrams daily. Nine cases were excluded from the study because they did not have at least two rating scales within a minimum interval of one year, and six were excluded for being co-infected with HIV and/or HCV. Thirty-nine patients met this criterion and were included for analysis. The majority were women (71.8%), the mean age was 56.51 years old (SD ± 9.74), and the median time of use of prednisone was 16 months. Thirty-two patients (82.05%) maintained the same OMDS, 5/39 (12.82%) had clinical worsening, and 2/39 (5.13%) improved. Conclusions: There was a trend toward clinical stability with the use of oral corticosteroids. However, randomized controlled trials are necessary to evaluate the use in clinical practices in all stages of HAM. Full article

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11 pages, 883 KiB

Open AccessReview

Avian Influenza: Could the H5N1 Virus Be a Potential Next Threat?

by Elena Imperia, Liliana Bazzani, Fabio Scarpa, Alessandra Borsetti, Nicola Petrosillo, Marta Giovanetti and Massimo Ciccozzi

Microbiol. Res. 2023, 14(2), 635-645; https://doi.org/10.3390/microbiolres14020045 - 9 May 2023

Cited by 8 | Viewed by 5708

Abstract

Avian influenza virus (AIV) poses a significant challenge to poultry production, with negative repercussions for both the economy and public health worldwide. Since January 2003, a total of 868 human cases of AIV H5N1 have been reported from four countries in the Western [...] Read more.

Avian influenza virus (AIV) poses a significant challenge to poultry production, with negative repercussions for both the economy and public health worldwide. Since January 2003, a total of 868 human cases of AIV H5N1 have been reported from four countries in the Western Pacific Region, as of 9 March 2023. When AIVs are circulating in poultry, there is a risk of sporadic infections and small clusters of human cases due to exposure to infected poultry or contaminated environments. The increase in reported A(H5N1) infections may reflect continued virus circulation in birds, as well as enhanced surveillance and diagnostic capacity resulting from the response to the COVID-19 pandemic. Numerous countermeasures, including vaccines and antiviral treatments, are available for influenza infection. However, their effectiveness is often debated due to the ongoing resistance to antivirals and the relatively low and unpredictable efficiency of influenza vaccines compared to other vaccines. Vaccination remains the primary method for preventing influenza acquisition or avoiding serious complications related to the disease. In this review, we summarize the global landscape of the Influenza A virus and provide insights into human clinical symptomatology. We call for urgent investment in genomic surveillance strategies to timely detect and shape the emergence of any potential viral pathogen, which is essential for epidemic/pandemic preparedness. Full article

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8 pages, 728 KiB

Open AccessArticle

Multiple Mechanisms Synergistically Induce Pseudomonas Aeruginosa Multiple Drug Resistance

by Pei Dai, Fangyan Jiao, Lulu Yang, Ousman Bajinka, Khalid A. Abdelhalim, Guojun Wu and Yurong Tan

Microbiol. Res. 2023, 14(2), 627-634; https://doi.org/10.3390/microbiolres14020044 - 6 May 2023

Viewed by 1912

Abstract

The aim of this study was to understand the molecular epidemiological characteristics and drug resistance mechanism of carbapenem-resistant Pseudomonas aeruginosa (CRPA) and to provide a theoretical basis for the prevention and treatment of CRPA infection in hospitals. A total of 34 CRPA strains [...] Read more.

The aim of this study was to understand the molecular epidemiological characteristics and drug resistance mechanism of carbapenem-resistant Pseudomonas aeruginosa (CRPA) and to provide a theoretical basis for the prevention and treatment of CRPA infection in hospitals. A total of 34 CRPA strains were isolated, and resistance to 13 commonly used antibiotics was detected using the TDR-300B Plus VitEK-2 compact automatic bacterial identification instrument. Then, carbapenemase production was detected using the Carbe NP test. RT-qPCR was used to detect the expression of efflux pump MexA and outer membrane protein OprD, and PCR amplification and sequence analysis were used to detect class Ⅰ integrons carried by drug resistance genes. Our results showed that of the 34 CRPAs, 22 were multi-drug resistant (MDR), and five were extensively drug-resistant (XDR). Sequencing analysis showed that class Ⅰ integron mainly carried aminoglycosides or quinolones resistance genes. Multiple mechanisms play important roles in the formation and development of MDR or XDR. Full article

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13 pages, 2296 KiB

Open AccessArticle

Pharmacological Effects of Lactobacillus casei ATCC 7469 Fermented Soybean and Green Microalgae, Chlorella vulgaris, on Diabetic Rats

by Asmaa Abdella, Fatma I. Abou-Elazm and Shaymaa Wagdy El-Far

Microbiol. Res. 2023, 14(2), 614-626; https://doi.org/10.3390/microbiolres14020043 - 30 Apr 2023

Cited by 1 | Viewed by 2338

Abstract

Type 2 diabetes mellitus (T2DM) is a complex, multifactorial metabolic disorder mainly characterized by chronic hyperglycemia. It has become a significant, serious disease worldwide, presenting a huge risk to human life and health. This study aimed to investigate the hypoglycemic effect of Lactobacillus [...] Read more.

Type 2 diabetes mellitus (T2DM) is a complex, multifactorial metabolic disorder mainly characterized by chronic hyperglycemia. It has become a significant, serious disease worldwide, presenting a huge risk to human life and health. This study aimed to investigate the hypoglycemic effect of Lactobacillus casei ATCC 7469 fermented soy flour extract and Chlorella vulgaris extract on Sprague-Dawley rats with T2DM induced by low-dose streptozotocin administration (STZ) compared to pioglitazone as a reference drug. Treatment with Lactobacillus casei ATCC 7469 fermented soy flour and Chlorella vulgaris resulted in a significant improvement in body weight, glucose tolerance, blood glucose level, and insulin resistance (p < 0.05). It also resulted in a significant decrease in total cholesterol (T.C), triglycerides (T.G), low-density lipoprotein (LDL), and very low-density lipoprotein (VLDL) (p < 0.05) and a significant increase in high-density lipoprotein (HDL) (p < 0.05). It also resulted in the improvement of liver oxidative biomarkers. Moreover, it prevented pancreatic histopathological changes. Lactobacillus casei ATCC 7469 fermented soy flour extract and Chlorella vulgaris extract had hypoglycemic, hypolipidemic, and antioxidant activity similar to pioglitazone. Full article

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11 pages, 532 KiB

Open AccessArticle

Isolation of a Multidrug-Resistant vanA-Positive Enterococcus faecium Strain from a Canine Clinical Sample in Greece

by Marios Lysitsas, Eleftherios Triantafillou, Ioannis Tzavaras, Panagiota Karamichali, Kiriakos Agathaggelidis, Constantina N. Tsokana, Esmeralda Dushku, Anna Katsiaflaka, Charalambos Billinis and George Valiakos

Microbiol. Res. 2023, 14(2), 603-613; https://doi.org/10.3390/microbiolres14020042 - 30 Apr 2023

Viewed by 1958

Abstract

An Enterococcus faecium strain was obtained from a paraprostatic cyst of a 17-year-old dog in Greece. Antibiotic susceptibility testing (AST) was accomplished by disc diffusion and MIC methods, and the isolate demonstrated a multidrug-resistant (MDR) phenotype against a great variety of antibiotics, such [...] Read more.

An Enterococcus faecium strain was obtained from a paraprostatic cyst of a 17-year-old dog in Greece. Antibiotic susceptibility testing (AST) was accomplished by disc diffusion and MIC methods, and the isolate demonstrated a multidrug-resistant (MDR) phenotype against a great variety of antibiotics, such as β-Lactams, Quinolones, Macrolides, Tetracyclines, Rifampin, Nitrofurantoin, and surprisingly, Glycopeptides, Fosfomycin and Gentamicin (high-level). Molecular screening for Vancomycin resistance genes was carried out, and a vanA gene cluster was identified. To our knowledge, this is the first report of a vanA-positive E. faecium strain isolated from a companion animal in Greece. Importantly, this strain was related with the presence of paraprostatic cysts, a pathological condition requiring treatment. The presence of a highly resistant isolate in a canine clinical sample and the consequent need for treatment constitutes a new challenge for veterinarians due to the lack of available treatment options. Our findings indicate the occurrence of respective bacteria in companion animals, which could act as a reservoir of epidemic MDR strains or relevant mobile genetic elements (MGE) in the community, constituting a threat for public health. Full article

(This article belongs to the Special Issue Advances in Enterococcus Associated with Wildlife)

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12 pages, 2264 KiB

Open AccessCommunication

Multiplex Detection of Antimicrobial Resistance Genes for Rapid Antibiotic Guidance of Urinary Tract Infections

by Mohammed Harris, Tracy Fasolino, Nicole J. Davis, Diana Ivankovic and Noel Brownlee

Microbiol. Res. 2023, 14(2), 591-602; https://doi.org/10.3390/microbiolres14020041 - 29 Apr 2023

Cited by 3 | Viewed by 5418

Abstract

Identification of antimicrobial resistance markers in urinary tract infections could provide a more targeted approach in the diagnosis and treatment of UTIs while reducing overall public health burdens. We describe a molecular assay as a diagnostic tool for antibiotic resistance characterization to promote [...] Read more.

Identification of antimicrobial resistance markers in urinary tract infections could provide a more targeted approach in the diagnosis and treatment of UTIs while reducing overall public health burdens. We describe a molecular assay as a diagnostic tool for antibiotic resistance characterization to promote faster diagnosis of antibiotic regimens compared to standard microbiology techniques. Targeted antibiotic usage for pathogenic infections remains a main goal for effective antibiotic treatment protocols and reducing the overall public health burden. Rapid identification of the pathogen(s) causing the infection and harboring the antibiotic resistance gene is also a main area of exploration for antibiotic appropriation and stewardship. Urinary tract infections are a common clinical disease and reservoir for pathogenic infection and the development of antibiotic resistance, especially in hospital- and community-acquired settings. Standard methods require urine culture, which is time consuming and relies on phenotypic characterization. A genetic diagnostic method is warranted for the rapid molecular characterization of antibiotic resistance genes to reduce inappropriate exposure to antibiotics while improving the overall treatment model for urinary tract infections. The purpose of this study is to demonstrate logical viability for real-time molecular diagnostics for early identification, active surveillance and overall targeted antibiotic stratification that is proposed as an in vitro rapid and comprehensive tool for assessing proper antibiotic stewardship in UTIs. Here, we describe a multiplex real-time fluorescence polymerase chain reaction (PCR) for probe-based detection of the top 24 antibiotic resistance genes with targeted relationships to target molecular drug classes and administered antibiotics. Multiplexed analysis based on molecular features enables rapid testing while shifting the diagnostic detection paradigm from monocentric infections towards polymicrobial infections. We utilized 366 samples from the FDA-CDC Antimicrobial Resistance Isolate Bank to test the efficacy of the assay and propose a model to infer the identity of bacterial isolates. We found that, in addition to a high level of accuracy in predicting bacterial genus classification, the assay was mostly in agreement with CDC-tested genotypic and phenotypic results. This study provides evidence for using genetic diagnostic methods, such as multiplex qPCR, in the rapid identification of antibiotic resistance (ABR) genes for the characterization and treatment of urinary tract infections. Full article

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11 pages, 1597 KiB

Open AccessArticle

The Impact of Antimicrobial Resistance on Outcomes for Patients Undergoing Coronary Artery Bypass Graft and Valve Surgery: A Retrospective Cohort Study of Hospital Admissions Data from the National Inpatient Sample

by Kirellos Abbas Said, Maximillian Will, Adnan I. Qureshi and Chun Shing Kwok

Microbiol. Res. 2023, 14(2), 580-590; https://doi.org/10.3390/microbiolres14020040 - 19 Apr 2023

Viewed by 1722

Abstract

Background: There is uncertainty regarding the impact of multidrug-resistant organisms on patients that undergo cardiac surgery. Methods: A retrospective cohort study was performed by using 2016–2019 data from the National Inpatient Sample in the United States to evaluate the proportion of admissions with [...] Read more.

Background: There is uncertainty regarding the impact of multidrug-resistant organisms on patients that undergo cardiac surgery. Methods: A retrospective cohort study was performed by using 2016–2019 data from the National Inpatient Sample in the United States to evaluate the proportion of admissions with a diagnosis of antimicrobial resistance who also underwent coronary artery bypass graft or valve surgery. Results: A total of 1,260,630 admissions were included in the analysis, of which 2045 (0.16%) had antimicrobial resistance. Compared to patients without resistance, those with antimicrobial resistance were more likely to be female (52.8% vs. 31.5%, p < 0.001), and die in a hospital (7.1% vs. 2.4%, p < 0.001). The length of stay and cost were significantly higher for patients with antimicrobial resistance (15 vs. 7 days and USD 69,135 vs. USD 43,740, respectively). Antimicrobial resistance was not associated with increased in-hospital mortality (OR 1.38; 95% CI 0.86–2.21, p = 0.18), although it was associated with an increase in length of stay (coefficient 7.65; 95% CI 6.91–8.39, p < 0.001), and cost (coefficient USD 25,240 [21,626–28,854], p < 0.001). Conclusions: Antimicrobial resistance in patients that undergo cardiac surgery is not common, yet its burden is substantial as it can double the length of stay and increase costs by more than USD 20,000. Full article

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21 pages, 2047 KiB

Open AccessArticle

miR-155-Induced Activation of Pro-Inflammatory Stat1/TBX21 Pathway and M1-Signature Genes Incite Macrophage Apoptosis and Clearance of Mycobacterium fortuitum in Zebrafish

by Priyanka Mehta, Debika Datta, Priyanka Dahiya and Shibnath Mazumder

Microbiol. Res. 2023, 14(2), 559-579; https://doi.org/10.3390/microbiolres14020039 - 13 Apr 2023

Viewed by 2052

Abstract

The role of microRNAs (miRNAs) in Mycobacterium fortuitum pathogenesis is not well illustrated. Using zebrafish kidney macrophages (ZFKM) we observed that M. fortuitum triggers miR-155 expression, and the TLR-2/NF-κB axis plays a key role in initiating the process. We report that mir-155 activates [...] Read more.

The role of microRNAs (miRNAs) in Mycobacterium fortuitum pathogenesis is not well illustrated. Using zebrafish kidney macrophages (ZFKM) we observed that M. fortuitum triggers miR-155 expression, and the TLR-2/NF-κB axis plays a key role in initiating the process. We report that mir-155 activates the pro-inflammatory Stat1/TBX21 pathway in M. fortuitum-infected ZFKM. Our results further reveal the role of miR-155 in M1-macrophage polarisation during M. fortuitum infection. We observed that miR-155 inhibits socs1 expression augmenting the expression of tnf-α, il-12 and ifn-γ in infected ZFKM. Additionally, attenuating miR-155 inhibited ZFKM apoptosis and increased the intracellular bacterial load implicating its pro-apoptotic and bactericidal role in M. fortuitum pathogenesis. This is the first report on the role of miRNA in regulating innate immunity to mycobacteria in fish. We propose that the TLR-2/NF-κB axis triggers miR-155 expression, which in turn represses socs1 and promotes the development of M1-macrophages. Thus, the functional miR-155/Stat1/TBX21pathway induces a pro-inflammatory milieu favouring ZFKM apoptosis and M. fortuitum clearance. Therefore, our study unveils the role of miR-155 in the hierarchy of events leading to M. fortuitum-induced apoptosis and bacterial clearance in fish that is still not explored in detail. Full article

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16 pages, 1642 KiB

Open AccessArticle

Novel Low-Alcohol Sangria-Type Wine Products with Immobilized Kefir Cultures and Essential Oils

by Anastasios Nikolaou, Valentini Santarmaki, Gregoria Mitropoulou, Georgios Sgouros and Yiannis Kourkoutas

Microbiol. Res. 2023, 14(2), 543-558; https://doi.org/10.3390/microbiolres14020038 - 13 Apr 2023

Cited by 1 | Viewed by 2482

Abstract

Low-alcohol wines (ranging from <0.5 to 10.5% vol) are novel products that have been steadily gaining scientific and commercial attention. Over the past few years, consumer interest in healthier foods has augmented the development of novel functional products containing probiotic microorganisms, while the [...] Read more.

Low-alcohol wines (ranging from <0.5 to 10.5% vol) are novel products that have been steadily gaining scientific and commercial attention. Over the past few years, consumer interest in healthier foods has augmented the development of novel functional products containing probiotic microorganisms, while the urge for a reduction in chemical preservatives has shifted the food and wine industry’s interest to natural alternatives, such as essential oils (EOs). In the present study, low-alcohol (~6% vol) wines with (wet or dried) immobilized kefir cultures on fruit pieces, and essential oils (Citrus medica or Cinnamomum zeylanicum) were produced and evaluated for their properties. The viability of the immobilized kefir cultures on apple and pear pieces was not affected by the addition of EOs, and levels >7 logcfu/g were maintained after 2 h of immersion in wines. HS-SPME GC/MS analysis revealed characteristic compounds originating from the chemical composition of the added EOs in the final products. Principal component analysis (PCA) revealed that the relative content of terpenes, alcohols and carbonyl compounds played a major role in the discrimination of low-alcohol wine products. EO addition affected the products’ sensory evaluation and resulted in significantly higher aroma and taste density compared to control samples. Notably, all novel Sangria-type wine variants were approved during preliminary sensory evaluation. Full article

(This article belongs to the Collection Microbiology and Technology of Fermented Foods)

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36 pages, 4541 KiB

Open AccessReview

Drug Resistance: An Incessant Fight against Evolutionary Strategies of Survival

by Francisco Ramos-Martín and Nicola D’Amelio

Microbiol. Res. 2023, 14(2), 507-542; https://doi.org/10.3390/microbiolres14020037 - 6 Apr 2023

Cited by 8 | Viewed by 5726

Abstract

The inherent capacity of all organisms to evolve under selective pressure has created multidrug-resistant microbes and cells that are now threatening decades of progress in human health introduced by the advent of antibiotics. This resistance is developed by all pathogens, from bacteria to [...] Read more.

The inherent capacity of all organisms to evolve under selective pressure has created multidrug-resistant microbes and cells that are now threatening decades of progress in human health introduced by the advent of antibiotics. This resistance is developed by all pathogens, from bacteria to cancer cells, through fungi, parasites, or the seemingly simpler entities, i.e., viruses. In this review, we give an overview on this phenomenon, describing the mechanisms by which resistant organisms manage to evade the action of drugs. We also review existing therapies, including some of the most recent. This bibliographic review shows how, despite the encouraging progress that has been achieved in many areas, a permanent effort from scientists is necessary and will always be needed in order to compensate for the continuous microbial response intrinsically linked to the evolutionary process. Full article

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15 pages, 2665 KiB

Open AccessOpinion

Clostridium butyricum Strain MIYAIRI 588 (CBM588) as a Precision Probiotic Therapy in the Ketogenic Diet: A Possible Application?

by Alexander Bertuccioli, Marco Cardinali, Giordano Zonzini, Marco Neri, Chiara Maria Palazzi, Aurora Gregoretti, Massimiliano Cazzaniga and Francesco Di Pierro

Microbiol. Res. 2023, 14(2), 492-506; https://doi.org/10.3390/microbiolres14020036 - 6 Apr 2023

Cited by 3 | Viewed by 7326

Abstract

The ketogenic diet has proven to be effective in many recent studies not only as a weight-losing strategy but also as a valuable add-on therapy in medical conditions such as diabetes and epilepsy. Additionally, frequent conditions such as autism spectrum disorders and Alzheimer [...] Read more.

The ketogenic diet has proven to be effective in many recent studies not only as a weight-losing strategy but also as a valuable add-on therapy in medical conditions such as diabetes and epilepsy. Additionally, frequent conditions such as autism spectrum disorders and Alzheimer disease could have a benefit derived from ketogenic diet metabolic changes. Many of these benefits could be driven by an intestinal microbiota change. While the effects of a ketogenic diet on microbiota should still be thoroughly clarified, as most studies observe an increase in bacterial strains considered neuroprotective such as Akkermansia muciniphila, with a concomitant reduction in some pathogenic strains such as Salmonella spp. it is important to highlight how many studies show a reduction in butyrate-producing strains, leading to a colonic proinflammatory state with increased intestinal permeability and an increase in pathogenic bacterial strains. The Clostridium butyricum strain MIYAIRI 588 (CBM588) is a butyrate-producing strain that was recently approved for human use in Europe due to its safety and effectiveness. The beneficial effect of CBM588 on the human colon could derive from a mucosal layer thickness increase and mucosal immune cell regulation, leading to a reduction in diarrhea and mucosal damage. Additionally, CBM588 could improve systemic insulin sensitivity and reduce the splanchnic organ inflammatory state. Therefore, CBM588 is a bacterial strain that should be considered an add-on when following a ketogenic diet, leading to a reduction in some of the potential gastrointestinal side effects and improving weight management through increased insulin sensitivity and the optimization of the lipid metabolism. Full article

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26 pages, 2032 KiB

Open AccessReview

Sporulation, Structure Assembly, and Germination in the Soil Bacterium Bacillus thuringiensis: Survival and Success in the Environment and the Insect Host

by Gloria G. Guerrero M.

Microbiol. Res. 2023, 14(2), 466-491; https://doi.org/10.3390/microbiolres14020035 - 4 Apr 2023

Cited by 3 | Viewed by 7729

Abstract

Bacillus thuringiensis (Bt) is a rod-shaped, Gram-positive soil bacterium that belongs to the phylum Firmicutes and the genus Bacillus. It is a spore-forming bacterium. During sporulation, it produces a wide range of crystalline proteins that are toxic to different orders of [...] Read more.

Bacillus thuringiensis (Bt) is a rod-shaped, Gram-positive soil bacterium that belongs to the phylum Firmicutes and the genus Bacillus. It is a spore-forming bacterium. During sporulation, it produces a wide range of crystalline proteins that are toxic to different orders of insects. Sporulation, structure assembly, and germination are essential stages in the cell cycle of B. thuringiensis. The majority of studies on these issues have focused on the model organism Bacillus subtilis, followed by Bacillus cereus and Bacillus anthracis. The machinery for sporulation and germination extrapolated to B. thuringiensis. However, in the light of recent findings concerning the role of the sporulation proteins (SPoVS), the germination receptors (Gr), and the cortical enzymes in Bt, the theory strengthened that conservation in sporulation, structure assembly, and germination programs drive the survival and success of B. thuringiensis in the environment and the insect host. In the present minireview, the latter pinpointed and reviewed. Full article

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12 pages, 2342 KiB

Open AccessArticle

Flow Cytometric Investigation of Salinicola halophilus S28 Physiological Response Provides Solid Evidence for Its Uncommon and High Ability to Face Salt-Stress Conditions

by Belén Juárez-Jiménez, Massimiliano Fenice, Marcella Pasqualetti, Barbara Muñoz-Palazon, David Correa-Galeote, Martina Braconcini and Susanna Gorrasi

Microbiol. Res. 2023, 14(2), 454-465; https://doi.org/10.3390/microbiolres14020034 - 1 Apr 2023

Viewed by 1828

Abstract

In a previous work, some bacterial strains isolated from the Saline di Tarquinia marine salterns (Viterbo, Italy) showed very unusual growth profiles in relation to temperature and salinity variations when grown in solid media. In particular, Salinicola halophilus S28 showed optimal or suboptimal [...] Read more.

In a previous work, some bacterial strains isolated from the Saline di Tarquinia marine salterns (Viterbo, Italy) showed very unusual growth profiles in relation to temperature and salinity variations when grown in solid media. In particular, Salinicola halophilus S28 showed optimal or suboptimal growth in a very wide range of NaCl concentrations, suggesting a great coping ability with salinity variations. These intriguing outcomes did not fit with the general Salinicola halophilus description as a moderately halophilic species. Therefore, this study profiles the actual physiological status of S28 cells subjected to different NaCl concentrations to provide evidence for the actual coping ability of strain S28 with broad salinity variations. Flow cytometry was selected as the evaluation method to study the physiological status of bacterial cells subjected to different salinity levels, monitoring the strain response at different growth phases over 72 h. Strain S28 showed maximal growth at 8% NaCl; however, it grew very well with no statistically significant differences at all salinity conditions (4–24% NaCl). Flow cytometric results provided clear evidence of its actual and strong ability to face increasing salinity, revealing a good physiological response up to 24% of NaCl. In addition, strain S28 showed very similar cell physiological status at all salinity levels, as also indicated by the flat growth profile revealed in the range of 4–24% NaCl. This is the first study regarding the physiological response during the growth of halophilic bacteria under different conditions of salinity via flow cytometry. This technique represents an effective tool for the investigation of the physiological status of each cell, even if it is somehow underrated and underused by microbiologists for this purpose. Full article

(This article belongs to the Topic Marine Microorganisms: Diversity, Bioactivity and Applications)

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Microbiol. Res., Volume 14, Issue 2 (June 2023) – 24 articles

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