Hasil untuk "Microbiology"

Chenxi Li, Chenyang Tang, Xiqian Liu et al.

ABSTRACT Membrane-associated RING-CH-type finger (MARCH) proteins, a class of E3 ubiquitin ligases, have been reported to be involved in the infection of multiple viruses and the regulation of type I interferon (IFN) production. However, the specific role and mechanisms by which MARCH proteins influence Japanese encephalitis virus (JEV) infection remain poorly understood. Here, we systematically investigate the functional relevance of MARCH proteins in JEV replication by examining the effects of siRNA-mediated knockdown of MARCHs on viral infection. We identified MARCH5 as a positive regulator of JEV replication. The knockout of MARCH5 dramatically reduced viral yields, whereas its overexpression significantly enhanced JEV replication. Mechanistically, MARCH5 specifically interacts with the JEV envelope (E) protein and promotes its K27-linked polyubiquitination at the lysine (K) residues 136 and 166. This ubiquitination enhances viral attachment to permissive cells. Substituting these lysine residues with arginine (R) attenuated JEV replication in vitro and reduced viral virulence in vivo. Furthermore, JEV infection upregulated the expression of MARCH5. We also discovered that MARCH5 degrades mitochondrial antiviral-signaling protein (MAVS) through the ubiquitin-proteasome pathway by catalyzing its K48-linked ubiquitination, thereby inhibiting type I IFN production in JEV-infected cells. This suppression of type I IFN further facilitates JEV infection. In conclusion, these findings disclosed a novel role of MARCH5 in positively regulating JEV infection and revealed an important mechanism employed by MARCH5 to regulate the innate immune response.IMPORTANCEJEV is the leading cause of viral encephalitis in many countries of Asia with an estimated 100,000 clinical human cases and causes economic loss to the swine industry. Until now, there is no clinically approved antiviral for the treatment of JEV infection. Although vaccination prophylaxis is widely regarded as the most effective strategy for preventing Japanese encephalitis (JE), the incidence of JE cases continues to rise. Thus, a deeper understanding of virus-host interaction will enrich our knowledge of the mechanisms underlying JEV infection and identify novel targets for the development of next-generation live-attenuated vaccines and antiviral therapies. To the best of our knowledge, this study is the first to identify MARCH5 as a pro-viral host factor that facilitates JEV infection. We elucidated two distinct mechanisms by which MARCH5 promotes JEV infection. First, MARCH5 interacts with viral E protein and mediates the K27-linked ubiquitination of E protein at the K136 and K166 residues to facilitate efficient viral attachment. Furthermore, double mutations of K136R-K166R attenuated JEV infection in vitro and reduced viral virulence in mice. Second, the upregulated expression of MARCH5 induced by JEV infection further suppresses the RIG-I-like receptor (RLR) signaling pathway to benefit viral infection. MARCH5 downregulates type I IFN production by conjugating the K48-linked polyubiquitin at the K286 of MAVS, which leads to MAVS degradation through the ubiquitin-proteasome pathway. In summary, this study provides novel insights into the role played by MARCH proteins in JEV infection and identifies specific ubiquitination sites on JEV E protein that could be targeted for viral attenuation and the development of antiviral therapeutics.

Bruna Del Acqua Barbosa, Livia Maria de Paula Castro, Isabella Guidini Benacchio et al.

Introdução: Meningite é uma inflamação das meninges, podendo ser de etiologia infecciosa ou não, sendo doença de notificação compulsória no Brasil. Apresenta caráter endêmico com períodos de surtos. 2014 foi ano crítico, com subsequente tendência de queda nas incidências. Um dos principais agentes etiológicos da meningite bacteriana é o coco gram-negativo Neisseria meningitidis, o qual é conhecido como meningococo e pode ser classificado em 13 sorogrupos: A, B, C, D, X, Y, Z, E-29, W-135, H, I, K e L. Os sorogrupos A e C são os mais epidêmicos, e foram responsáveis pelas duas grandes epidemias meningocócicas entre 1971 e 1975. A partir de então, o Brasil experienciou pequenas microepidemias. Objetivo: Analisar o número de casos confirmados e a letalidade dos sorotipos A, B, C, Y e W135 de meningococo no período de 2014 a 2022 no Brasil. Método: Estudo epidemiológico descritivo retrospectivo, baseado em dados do Sistema de Informações de Agravos de Notificações do Sistema Único de Saúde (SINAN/DATASUS). Foram incluídos os casos confirmados de meningite por meningococo de 2014 a 2022 no Brasil. As variáveis utilizadas foram ano do primeiro sintoma (2014 a 2022), sorogrupo (A, B, C, Y e W135) e evolução a óbito. Foi calculada a letalidade de cada sorogrupo, com os valores escritos até a segunda casa decimal. Resultados: No período descrito, houveram 1.967 casos confirmados, dos quais 7 foram do sorogrupo A, 584 do B, 1.152 do C, 64 do Y e 160 do W135. O ano de 2014 marcou o maior valor, com 365 casos, sendo o sorogrupo C o mais prevalente, responsável por 250 casos, e o Y o mais letal, com taxa de 30%. Em seguida, 2015 e 2016 registraram quedas, com, respectivamente, 292 e 239 casos. Em 2017, houve elevação, com 303 casos. Os anos de 2018 a 2021 registraram sucessivas quedas, com 271, 224, 75 e 44 casos anuais, respectivamente. Por fim, 2022 apresentou nova alta, com 116 casos. O número de óbitos nos 9 anos foi de 1 do sorogrupo A, 48 do B, 135 do C, 9 do Y e 27 do W135. O cálculo da letalidade no período total revelou frações equivalentes a, respectivamente, 14,28%, 8,21%, 11,71%, 14,06% e 16,87%. Conclusão: Embora o sorogrupo C seja mais prevalente, W135 foi o mais letal na totalidade dos anos analisados. Neste período, 2014 apresentou maior número de casos, confirmando a tendência esperada de queda nos anos subsequentes. Uma possível explicação para essa queda é a elevação na taxa de vacinação contra meningococo, porém estudos adicionais são necessários.

Érica Mendes dos Santos, Lucas Malvezzi de Macedo, Janaína Artem Ataide et al.

Abstract Consumer demand for natural, chemical-free products has grown. Food industry residues, like coffee pulp, rich in caffeine, chlorogenic acid and phenolic compounds, offer potential for pharmaceutical and cosmetic applications due to their antioxidant, anti-inflammatory, and antibacterial properties. Therefore, the objective of this work was to develop a phytocosmetic only with natural products containing coffee pulp extract as active pharmaceutical ingredient with antioxidant, antimicrobial and healing activity. Eight samples from Coffea arabica and Coffea canephora Pierre were analyzed for caffeine, chlorogenic acid, phenolic compounds, tannins, flavonoids, cytotoxicity, antibacterial activity, and healing potential. The Robusta IAC—extract had the greatest prominence with 192.92 μg/mL of chlorogenic acid, 58.98 ± 2.88 mg GAE/g sample in the FRAP test, 79.53 ± 5.61 mg GAE/g sample in the test of total phenolics, was not cytotoxic, and MIC 3 mg/mL against Staphylococcus aureus. This extract was incorporated into a stable formulation and preferred by 88% of volunteers. At last, a scratch assay exhibited the formulation promoted cell migration after 24 h, therefore, increased scratch retraction. In this way, it was possible to develop a phytocosmetic with the coffee pulp that showed desirable antioxidant, antimicrobial and healing properties.

Severine Matheus, Charlotte Balière, Veronique Hourdel et al.

Background: Tropical infectious diseases pose a significant burden on global public health, exacerbated by the emergence of new pathogens. French Guiana (FG), a French overseas department in northeastern South America, presents favorable conditions for the emergence of zoonotic pathogens due to its tropical climate and diverse ecosystems. Over the past two decades, various emerging zoonotic pathogens have been detected in patients with severe infections, though, many other severe human infectious diseases remain undocumented. Aim: This prospective pilot study aims to identify infectious pathogens responsible for severe infections in French Guiana using routine diagnostic tests and metagenomic approach. Methods: This study was conducted from July 2013 to December 2015. It included consenting patients of all ages and sexes admitted to the ICU for severe infections in FG. Biological samples were collected based on clinical presentation (plasma, serum, nasopharyngeal swab, broncho-alveolar liquid, cerebrospinal fluid). All samples were collected in duplicate for routine microbiological tests and potential metagenomic sequencing when initial investigations proved negative. Results: During the study period, 10.9% (89/813) of ICU admissions were due to community-acquired sepsis. Of these, 22/89 (24.7%) were enrolled. Routine diagnosis tests identified a causal pathogen in 54.5% (12/22) of cases, including arboviruses, influenza virus, Trypanosoma cruzi, Coxiella burnetti, enterovirus, Histoplasma sp, and Leptospira sp. Five of the 22 patients had an unfavorable outcome. Genomic sequence analyses allowed identification of the first human case of Leptospira santarosai in the region. Conclusion: This pilot study underscores the array of pathogens causing severe infections in French Guiana. It emphasizes the need to investigate sepsis of unknown origin in a region susceptible to pathogen emergence or reemergence. [J Microbiol Infect Dis 2024; 14(4.000): 178-185]

Sk Injamamul Islam, Mohamed H. Hamad, Wanarit Jitsamai et al.

Clinostomum species, a parasitic pathogen of freshwater fish, is widely distributed and infects various host species. Recently, the pathological effect due to Clinostomum metacercarial infection was described in aquaculture in Thailand; however, the global genetic diversity and population structure of this species have not been studied yet. Therefore, this study aimed to provide a detailed description of genetic diversity and population dynamics of the digenean Clinostomum isolated from Trichopodus pectoralis with globally recorded Clinostomum species. The species was characterized molecularly by analyzing 18S rDNA and inter-transcribed spacer biomarker genes (ITS1 and ITS2). A BLAST search discovered that the 18S rDNA and ITS sequence had a 100% sequence similarity with Clinostomum piscidium isolated from India and Thailand. A comprehensive analysis revealed the presence of 12 distinct haplotypes among the Clinostomum populations. This study suggests that distinct patterns of genetic variation were identified by analyzing molecular variance, pairwise Fst, and employing structure analysis. It was observed that a gradient of genetic variation exists within continents, characterized by higher levels within different groups and lower levels of genetic differentiation. Additionally, a notable presence of mixed haplotypes was observed. The results of neutrality testing suggest that there has been a significant expansion in the populations of Clinostomum in India, America, and Kenya. The discoveries from this study will provide a valuable contribution to comprehending the genetics and evolution of Clinostomum species. Furthermore, key findings will be essential in developing efficient management approaches to prevent and control this parasite.

Takaya Oda

HML6-c14, a long terminal repeat (LTR)-type retrotransposon identified by expressed sequence tag (EST) database screening, was found to undergo RNA processing resembling that of placental tissue by in vitro expression analysis. Previous in situ hybridization studies using normal placental tissue showed that the transcript remained in the nucleus. However, among the transcripts forcedly expressed in cultured cells, the transcript that retained the 3.3 kb intron was observed in the nucleus, and a part of the spliced transcript was observed outside the nucleus. To verify whether this cytoplasmic transcript could be translated, we examined the coding potential of the open reading frame (ORF), consisting of 109 codons on the spliced transcript, along with two other putative ORFs detected in the intronic region. As a result, none of the ORF-derived products could be detected by Western blotting as fusion proteins tagged with the FLAG epitope, suggesting that HML6-c14 belongs to a group of long non-coding RNA (lncRNA) genes. Promoter analysis of the upstream 6.4 kb genomic region also suggested that the 5′-LTR itself potentially retains high promoter activity. Despite losing the ability to produce functional proteins, HML6-c14 continues to retain its transcriptional ability while converting to an lncRNA gene, which is an interesting subject for future research.

Arthika Manoharan, Arthika Manoharan, Jessica Farrell et al.

IntroductionProteus mirabilis is a key pathobiont in catheter-associated urinary tract infections (CA-UTIs), which is well known to form crystalline biofilms that occlude catheters. Urease activity alkylates urine through the release of ammonia, consequentially resulting in higher levels of Mg2+ and Ca2+ and formation of crystals. In this study, we showed that N-acetyl cysteine (NAC), a thiol antioxidant, is a potent urease inhibitor that prevents crystalline biofilm formation.MethodsTo quantify urease activity, Berthelot’s method was done on bacterial extracts treated with NAC. We also used an in vitro catheterised glass bladder model to study the effect of NAC treatment on catheter occlusion and biofilm encrustation in P. mirabilis infections. Inductively-coupled plasma mass spectrometry (ICP-MS) was performed on catheter samples to decipher elemental profiles.ResultsNAC inhibits urease activity of clinical P. mirabilis isolates at concentrations as low as 1 mM, independent of bacterial killing. The study also showed that NAC is bacteriostatic on P. mirabilis, and inhibited biofilm formation and catheter occlusion in an in vitro. A significant 4-8log10 reduction in viable bacteria was observed in catheters infected in this model. Additionally, biofilms in NAC treated catheters displayed a depletion of calcium, magnesium, or phosphates (>10 fold reduction), thus confirming the absence of any urease activity in the presence of NAC. Interestingly, we also showed that not only is NAC anti-inflammatory in bladder epithelial cells (BECs), but that it mutes its inflammatory response to urease and P. mirabilis infection by reducing the production of IL-6, IL-8 and IL-1b.DiscussionUsing biochemical, microbiological and immunological techniques, this study displays the functionality of NAC in preventing catheter occlusion by inhibiting urease activity. The study also highlights NAC as a strong anti-inflammatory antibiofilm agent that can target both bacterial and host factors in the treatment of CA-UTIs.

Darshika Manral, Doroteaciro Iovino, Olivier Jaillon et al.

Ocean currents are a key driver of plankton dispersal across the oceanic basins. However, species specific temperature constraints may limit the plankton dispersal. We propose a methodology to estimate the connectivity pathways and timescales for plankton species with given constraints on temperature tolerances, by combining Lagrangian modeling with network theory. We demonstrate application of two types of temperature constraints: thermal niche and adaptation potential and compare it to the surface water connectivity between sample stations in the Atlantic Ocean. We find that non-constrained passive particles representative of a plankton species can connect all the stations within three years at the surface with pathways mostly along the major ocean currents. However, under thermal constraints, only a subset of stations can establish connectivity. Connectivity time increases marginally under these constraints, suggesting that plankton can keep within their favorable thermal conditions by advecting via slightly longer paths. Effect of advection depth on connectivity is observed to be sensitive to the width of the thermal constraints, along with decreasing flow speeds with depth and possible changes in pathways.

Bambang Irawan, Inten Wahyuningtias, Niken Ayuningtyas et al.

Pineapple plantations leave a lot of plant biomass after the planting season ends. The abundant residue of pineapple plants causes problems due to the high content of lignocellulose, which is difficult to decompose naturally. This study aimed to isolate and characterize lignocellulolytic microfungi isolates from pineapple plantations. The information of this study was used as data to prepare an inoculum for the induction of pineapple litter composting that was resistant to stress to pineapple plantation habitat. The results showed that there were 11 dominant lignocellulolytic microfungi isolates found from pineapple litter and plantation soil. Using selective media, the selection showed five cellulolytic (Bioggp 3, 6, 9, 11, and 12); five xylanolytic (Bioggp 3, 6, 8, 9, and 12); and two ligninolytic microfungi isolates (Bioggp 2 and 5). Bioggp 3, 6, 9, and 12 are cellulolytic and xylanolytic with Bioggp 3 showing the highest cellulolytic index (4.0) and xylanolytic index (4.20). Testing of ligninolytic microfungi showed that the Bioggp 5 isolate had a stronger lignin indicator (color intensity = 4.0 and zone ratio of 1.47) than the Bioggp 2 isolate. Bioggp 9 had the highest cellulolytic isolate spore productivity at 4.5 × 108 spores/mL with 93.3% spore viability, and Bioggp 3 had the highest xylanolytic isolate spore productivity at 2.5 × 109 spores/mL with 89.3% spore viability. Bioggp 2 had the highest ligninolytic isolate spore productivity at 1.8 × 109 spores/mL, but Bioggp 5 showed the highest spore viability at 98.0%.

Patrice Cunningham, Emma Patton, Brandon N. VanderVeen et al.

Abstract Background Quercetin is an organic flavonoid present in several fruits and vegetables. The anti-inflammatory, antiviral, antioxidant, cardio-protective, anti-carcinogenic and neuroprotective properties demonstrated by this dietary supplement endorses it as a possible treatment for inflammatory diseases and cancer. Unfortunately, conflicting research has cast uncertainties on the toxicity of quercetin. The main purpose of this study was to determine if quercetin has any toxic properties in mice at doses that have shown efficacy in pre-clinical studies regarding cancer, cancer therapy, and their off-target effects. Methods A sub-chronic toxicity study of quercetin was examined in male and female CD2F1 mice. Three different doses of quercetin (62, 125, and 250 mg/kg of diet) were infused into the AIN-76A purified diet and administered to mice ad libitum for 98 days. Body weight (BW), food consumption, water intake, body composition, blood count, behavior, and metabolic phenotype were assessed at various timepoints during the course of the experiment. Tissue and organs were evaluated for gross pathological changes and plasma was used to measure alkaline phosphatase (AP), aspartate transaminase (AST), and alanine transaminase (ALT). Results We found that low (62 mg/kg of diet), medium (125 mg/kg of diet), and high (250 mg/kg of diet) quercetin feeding had no discernible effect on body composition, organ function, behavior or metabolism. Conclusions In summary, our study establishes that quercetin is safe for use in both female and male CD2F1 mice when given at ~ 12.5, 25, or 50 mg/kg of BW daily doses for 14 weeks (i.e. 98 days). Further studies will need to be conducted to determine any potential toxicity of quercetin following chronic ingestion.

Xiaohang Chen, Huifei Li, Haoyue Song et al.

Abstract Coronavirus disease 2019 (COVID‐19), caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), has wrought havoc on the world economy and people's daily lives. The inability to comprehensively control COVID‐19 is due to the difficulty of early and timely diagnosis, the lack of effective therapeutic drugs, and the limited effectiveness of vaccines. The body contains billions of extracellular vesicles (EVs), which have shown remarkable potential in disease diagnosis, drug development, and vaccine carriers. Recently, increasing evidence has indicated that EVs may participate or assist the body in defence, antagonism, recovery and acquired immunity against SARS‐CoV‐2. On the one hand, intercepting and decrypting the general intelligence carried in circulating EVs from COVID‐19 patients will provide an important hint for diagnosis and treatment; on the other hand, engineered EVs modified by gene editing in the laboratory will amplify the effectiveness of inhibiting infection, replication and destruction of ever‐mutating SARS‐CoV‐2, facilitating tissue repair and making a better vaccine. To comprehensively understand the interaction between EVs and SARS‐CoV‐2, providing new insights to overcome some difficulties in the diagnosis, prevention and treatment of COVID‐19, we conducted a rounded review in this area. We also explain numerous critical challenges that these tactics face before they enter the clinic, and this work will provide previous ‘meet change with constancy’ lessons for responding to future similar public health disasters. Extracellular vesicles (EVs) provide a ‘meet changes with constancy’ strategy to combat SARS‐CoV‐2 that spans defence, antagonism, recovery, and acquired immunity. Targets for COVID‐19 diagnosis, therapy, and prevention of progression may be found by capture of the message decoding in circulating EVs. Engineered and biomimetic EVs can boost effects of the natural EVs, especially anti‐SARS‐CoV‐2, targeted repair of damaged tissue, and improvement of vaccine efficacy.

Alexander McQuiston, Alexander McQuiston, Amir Emtiazjoo et al.

Lung transplant patients have the lowest long-term survival rates compared to other solid organ transplants. The complications after lung transplantation such as primary graft dysfunction (PGD) and ultimately chronic lung allograft dysfunction (CLAD) are the main reasons for this limited survival. In recent years, lung-specific autoantibodies that recognize non-HLA antigens have been hypothesized to contribute to graft injury and have been correlated with PGD, CLAD, and survival. Mounting evidence suggests that autoantibodies can develop during pulmonary disease progression before lung transplant, termed pre-existing autoantibodies, and may participate in allograft injury after transplantation. In this review, we summarize what is known about pulmonary disease autoantibodies, the relationship between pre-existing autoantibodies and lung transplantation, and potential mechanisms through which pre-existing autoantibodies contribute to graft injury and rejection.

I. Codina-Torrella, B. Guamis, A. Zamora et al.

Kazybayeva Saule, Dolgikh Svetlana, Kulshanov Shokan et al.

The intensification of viniculture involves the organization of the virus-tested planting material production, establishment of the basic parent plantings, certification of the virus-tested planting material with the control of genetic stability of the grape plants propagated in tissue culture. The modified nutritional medium was developed for microclonal propagation of vine in vitro with the content of the free amino acids: glycine and glutamine, increasing propagation factor up to 15% and the number of nodes on microplant up to 27%.

Deffner Veronika, Kreuzer Michaela, Sobotzki Christina et al.

C. Cazanave, K. Greenwood-Quaintance, A. Hanssen et al.

Shiping Wei, Zheng-long Jiang, Hao Liu et al.

Microbiologically induced deterioration (MID) causes corrosion of concrete by producing acids (including organic and inorganic acids) that degrade concrete components and thus compromise the integrity of sewer pipelines and other structures, creating significant problems worldwide. Understanding of the fundamental corrosion process and the causal agents will help us develop an appropriate strategy to minimize the costs in repairs. This review presents how microorganisms induce the deterioration of concrete, including the organisms involved and their colonization and succession on concrete, the microbial deterioration mechanism, the approaches of studying MID and safeguards against concrete biodeterioration. In addition, the uninvestigated research area of MID is also proposed.

S. Akhtar, M. Sarker, A. Hossain

J. Martínez, F. Baquero, D. Andersson

G. Kallstrom