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1.
Mol Plant Pathol ; 25(7): e13491, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38961768

RESUMEN

Root-knot nematodes (RKNs) are microscopic parasitic worms able to infest the roots of thousands of plant species, causing massive crop yield losses worldwide. They evade the plant's immune system and manipulate plant cell physiology and metabolism to transform a few root cells into giant cells, which serve as feeding sites for the nematode. RKN parasitism is facilitated by the secretion in planta of effector molecules, mostly proteins that hijack host cellular processes. We describe here a conserved RKN-specific effector, effector 12 (EFF12), that is synthesized exclusively in the oesophageal glands of the nematode, and we demonstrate its function in parasitism. In the plant, MiEFF12 localizes to the endoplasmic reticulum (ER). A combination of RNA-sequencing analysis and immunity-suppression bioassays revealed the contribution of MiEFF12 to the modulation of host immunity. Yeast two-hybrid, split luciferase and co-immunoprecipitation approaches identified an essential component of the ER quality control system, the Solanum lycopersicum plant bap-like (PBL), and basic leucine zipper 60 (BZIP60) proteins as host targets of MiEFF12. Finally, silencing the PBL genes in Nicotiana benthamiana decreased susceptibility to Meloidogyne incognita infection. Our results suggest that EFF12 manipulates PBL function to modify plant immune responses to allow parasitism.


Asunto(s)
Retículo Endoplásmico , Tylenchoidea , Animales , Retículo Endoplásmico/metabolismo , Tylenchoidea/fisiología , Tylenchoidea/patogenicidad , Proteínas del Helminto/metabolismo , Proteínas del Helminto/genética , Inmunidad de la Planta , Nicotiana/parasitología , Nicotiana/inmunología , Nicotiana/genética , Solanum lycopersicum/parasitología , Solanum lycopersicum/inmunología , Solanum lycopersicum/genética , Enfermedades de las Plantas/parasitología , Enfermedades de las Plantas/inmunología , Raíces de Plantas/parasitología , Raíces de Plantas/inmunología , Interacciones Huésped-Parásitos
2.
Exp Mol Pathol ; 138: 104915, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38964052

RESUMEN

A subset of head and neck squamous cell carcinomas present solely as metastatic disease in the neck and are of unknown primary origin (SCCUP). Most primary tumors will ultimately be identified, usually in the oropharynx. In a minority of cases, the primary site remains elusive. Here, we examine the role of ancillary testing, including mutational signature analysis (MSA), to help identify likely primary sites in such cases. Twenty-two cases of SCCUP in the neck, collected over a 10-year period, were classified by morphology and viral status; including human papillomavirus (HPV) testing by p16 immunohistochemistry (IHC) and RT-qPCR, as well as Epstein-Barr virus (EBV) testing by EBER-ISH. CD5 and c-KIT (CD117) IHC was done to evaluate for possible thymic origin in all virus-negative cases. Whole exome sequencing, followed by MSA, was used to identify UV signature mutations indicative of cutaneous origin. HPV was identified in 12 of 22 tumors (54.5%), favoring an oropharyngeal origin, and closely associated with nonkeratinizing tumor morphology (Fisher's exact test; p = 0.0002). One tumor with indeterminant morphology had discordant HPV and p16 status (p16+/HPV-). All tumors were EBV-negative. Diffuse expression of CD5 and c-KIT was identified in 1 of 10 virus-negative SCCUPs (10%), suggesting a possible ectopic thymic origin rather than a metastasis. A UV mutational signature, indicating cutaneous origin, was identified in 1 of 10 (10%) virus-negative SCCUPs. A cutaneous auricular primary emerged 3 months after treatment in this patient. Primary tumors became clinically apparent in 2 others (1 hypopharynx, 1 hypopharynx/larynx). Thus, after follow-up, 6 tumors remained unclassifiable as to the possible site of origin (27%). Most SCCUPs of the neck in our series were HPV-associated and thus likely of oropharyngeal origin. UV signature mutation analysis and additional IHC for CD5 and c-KIT for possible thymic origin may aid in further classifying virus-negative unknown primaries. Close clinical inspection of hypopharyngeal mucosa may also be helpful, as a subset of primary tumors later emerged at this site.


Asunto(s)
Neoplasias de Cabeza y Cuello , Neoplasias Primarias Desconocidas , Carcinoma de Células Escamosas de Cabeza y Cuello , Humanos , Neoplasias Primarias Desconocidas/virología , Neoplasias Primarias Desconocidas/patología , Neoplasias Primarias Desconocidas/genética , Masculino , Femenino , Persona de Mediana Edad , Anciano , Carcinoma de Células Escamosas de Cabeza y Cuello/virología , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/virología , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/genética , Infecciones por Papillomavirus/virología , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/genética , Proteínas Proto-Oncogénicas c-kit/genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/aislamiento & purificación , Herpesvirus Humano 4/patogenicidad , Inmunohistoquímica , Biomarcadores de Tumor/genética , Mutación , Anciano de 80 o más Años , Adulto , Papillomaviridae/genética , Papillomaviridae/patogenicidad , Papillomaviridae/aislamiento & purificación , Secuenciación del Exoma , Carcinoma de Células Escamosas/virología , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/genética
3.
Commun Biol ; 7(1): 812, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965407

RESUMEN

Wheat blast caused by Pyricularia oryzae pathotype Triticum is now becoming a very serious threat to global food security. Here, we report an essential pathogenicity factor of the wheat blast fungus that is recognized and may be targeted by a rice resistance gene. Map-based cloning of Pwt2 showed that its functional allele is the ACE1 secondary metabolite gene cluster of the wheat blast fungus required for its efficient penetration of wheat cell walls. ACE1 is required for the strong aggressiveness of Triticum, Eleusine, and Lolium pathotypes on their respective hosts, but not for that of Oryza and Setaria pathotypes on rice and foxtail millet, respectively. All ACE1 alleles found in wheat blast population are recognized by a rice resistance gene, Pi33, when introduced into rice blast isolates. ACE1 mutations for evading the recognition by Pi33 do not affect the aggressiveness of the rice blast fungus on rice but inevitably impair the aggressiveness of the wheat blast fungus on wheat. These results suggest that a blast resistance gene already defeated in rice may be revived as a durable resistance gene in wheat by targeting an Achilles heel of the wheat blast fungus.


Asunto(s)
Familia de Multigenes , Oryza , Enfermedades de las Plantas , Triticum , Triticum/microbiología , Enfermedades de las Plantas/microbiología , Oryza/microbiología , Ascomicetos/genética , Ascomicetos/patogenicidad , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Resistencia a la Enfermedad/genética , Factores de Virulencia/genética , Factores de Virulencia/metabolismo , Metabolismo Secundario/genética
4.
Virus Res ; 347: 199435, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38986742

RESUMEN

The bacterial diseases black leg and soft rot in potatoes cause heavy losses of potatoes worldwide. Bacteria within the genus Pectobacteriaceae are the causative agents of black leg and soft rot. The use of antibiotics in agriculture is heavily regulated and no other effective treatment currently exists, but bacteriophages (phages) have shown promise as potential biocontrol agents. In this study we isolated soft rot bacteria from potato tubers and plant tissue displaying soft rot or black leg symptoms collected in Danish fields. We then used the isolated bacterial strains as hosts for phage isolation. Using organic waste, we isolated phages targeting different species within Pectobacterium. Here we focus on seven of these phages representing a new genus primarily targeting P. brasiliense; phage Ymer, Amona, Sabo, Abuela, Koroua, Taid and Pappous. TEM image of phage Ymer showed siphovirus morphotype, and the proposed Ymer genus belongs to the class Caudoviricetes, with double-stranded DNA genomes varying from 39 kb to 43 kb. In silico host range prediction using a CRISPR-Cas spacer database suggested both P. brasiliense, P. polaris and P. versatile as natural hosts for phages within the proposed Ymer genus. A following host range experiment, using 47 bacterial isolates from Danish tubers and plants symptomatic with soft rot or black leg disease verified the in silico host range prediction, as the genus as a group were able to infect all three Pectobacterium species. Phages did, however, primarily target P. brasiliense isolates and displayed differences in host range even within the species level. Two of the phages were able to infect two or more Pectobacterium species. Despite no nucleotide similarity with any phages in the NCBI database, the proposed Ymer genus did share some similarity at the protein level, as well as gene synteny, with currently known phages. None of the phages encoded integrases or other genes typically associated with lysogeny. Similarly, no virulence factors nor antimicrobial resistance genes were found, and combined with their ability to infect several soft rot-causing Pectobacterium species from Danish fields, demonstrates their potential as biocontrol agents against soft rot and black leg diseases in potatoes.


Asunto(s)
Bacteriófagos , Especificidad del Huésped , Pectobacterium , Enfermedades de las Plantas , Solanum tuberosum , Pectobacterium/virología , Pectobacterium/genética , Pectobacterium/patogenicidad , Solanum tuberosum/microbiología , Solanum tuberosum/virología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/virología , Bacteriófagos/genética , Bacteriófagos/aislamiento & purificación , Bacteriófagos/fisiología , Bacteriófagos/clasificación , Dinamarca , Genoma Viral , Filogenia
5.
Comp Immunol Microbiol Infect Dis ; 111: 102214, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39002176

RESUMEN

MicroRNAs (miRNAs) have been shown to play an important regulatory role in the process of pathogenic infection. However, the miRNAs that regulate the pathogenic process of G. parasuis and their functions are still unknown. Here, high-throughput sequencing was used to quantify the expression of miRNA in piglet lung tissue after G. parasuis XX0306 strain infection. A total of 25 differentially expressed microRNAs (DEmiRNAs) were identified. GO and KEGG pathway enrichment analysis showed that many of the functions of genes that may be regulated by DEmiRNA are related to inflammatory response and immune regulation. Further studies found that ssc-miR-135 may promote the expression of inflammatory factors through NF-κB signaling pathway. Whereas, ssc-miR-155-3p inhibited the inflammatory response induced by G. parasuis, and its regulatory mechanism remains to be further investigated. This study provides a valuable reference for revealing the regulatory effects of miRNAs on the pathogenesis of G. parasuis. DATA AVAILABILITY: The datasets generated during the current study are not publicly available due to this study is currently in the ongoing research stage, and some of the data cannot be made public sooner yet, but are available from the corresponding author on reasonable request.


Asunto(s)
Infecciones por Haemophilus , Haemophilus parasuis , Inflamación , Pulmón , MicroARNs , Enfermedades de los Porcinos , Animales , MicroARNs/genética , Porcinos , Pulmón/microbiología , Pulmón/inmunología , Enfermedades de los Porcinos/microbiología , Enfermedades de los Porcinos/genética , Enfermedades de los Porcinos/inmunología , Inflamación/genética , Haemophilus parasuis/genética , Haemophilus parasuis/patogenicidad , Infecciones por Haemophilus/veterinaria , Infecciones por Haemophilus/inmunología , Infecciones por Haemophilus/microbiología , Infecciones por Haemophilus/genética , Perfilación de la Expresión Génica , FN-kappa B/metabolismo , FN-kappa B/genética , Transducción de Señal , Secuenciación de Nucleótidos de Alto Rendimiento , Regulación de la Expresión Génica , Transcriptoma , Metastrongyloidea/genética
7.
J Public Health Manag Pract ; 30(5): 688-700, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38985535

RESUMEN

CONTEXT: Most incident cases of cervical cancer in the United States are attributable to inadequate screening. Federally qualified health centers (FQHCs) serve a large proportion of women who are low-income, have no insurance, and are underserved-risk factors for insufficient cervical cancer screening. FQHCs must maintain quality measures to preserve their accreditation, address financial reimbursements, and provide quality care. Implementation of human papillomavirus (HPV) self-collection can improve cervical cancer screening coverage within FQHCs. OBJECTIVES: To understand perspectives from clinical personnel on current cervical cancer screening rates at FQHCs in North Carolina and the impact of implementing HPV self-collection among underscreened patients on screening rates and performance measures. DESIGN: The study used focus groups and key informant interviews. Coding-based thematic analysis was applied to both focus group and interview transcripts. Emergent themes regarding perspectives on self-collection implementation were mapped onto Consolidated Framework for Implementation Research (CFIR) constructs to identify future barriers and facilitators to implementation. SETTING: Two FQHCs in North Carolina and a cloud-based videoconferencing platform. PARTICIPANTS: Six FQHCs in North Carolina; 45 clinical and administrative staff from the 6 FQHCs; 1 chief executive officer (n = 6), 1 senior-level administrator (n = 6), 1 chief medical officer (n = 6), and 1 clinical data manager (n = 6) from each FQHC. MAIN OUTCOME MEASURE: Achievement of clinical perspectives. RESULTS: Societal-, practice-, and patient-level factors currently contribute to subpar cervical cancer screening rates. HPV self-collection was expected to improve screening uptake among underscreened women at FQHCs, and thus quality and performance measures, by offering an alternative screening approach for in-clinic or at-home use. Implementation barriers include financial uncertainties and HPV self-collection not yet a Food and Drug Administration-approved test. CONCLUSION: HPV self-collection has potential to improve cervical cancer screening quality and performance measures of FQHCs. For a successful implementation, multilevel factors that are currently affecting low screening uptake need to be addressed. Furthermore, the financial implications of implementation and approval of HPV self-collection as a test for cervical cancer screening quality measures need to be resolved.


Asunto(s)
Detección Precoz del Cáncer , Grupos Focales , Infecciones por Papillomavirus , Mejoramiento de la Calidad , Neoplasias del Cuello Uterino , Humanos , Femenino , North Carolina , Detección Precoz del Cáncer/métodos , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/prevención & control , Infecciones por Papillomavirus/diagnóstico , Adulto , Tamizaje Masivo/métodos , Tamizaje Masivo/normas , Persona de Mediana Edad , Manejo de Especímenes/métodos , Investigación Cualitativa , Papillomaviridae/aislamiento & purificación , Papillomaviridae/patogenicidad
8.
PLoS Pathog ; 20(7): e1012394, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38991026

RESUMEN

Staphylococcus aureus is a facultative intracellular pathogen of human macrophages, which facilitates chronic infection. The genotypes, pathways, and mutations influencing that phenotype remain incompletely explored. Here, we used two distinct strategies to ascertain S. aureus gene mutations affecting pathogenesis in macrophages. First, we analyzed isolates collected serially from chronic cystic fibrosis (CF) respiratory infections. We found that S. aureus strains evolved greater macrophage invasion capacity during chronic human infection. Bacterial genome-wide association studies (GWAS) identified 127 candidate genes for which mutation was significantly associated with macrophage pathogenesis in vivo. In parallel, we passaged laboratory S. aureus strains in vitro to select for increased infection of human THP-1 derived macrophages, which identified 15 candidate genes by whole-genome sequencing. Functional validation of candidate genes using isogenic transposon mutant knockouts and CRISPR interference (CRISPRi) knockdowns confirmed virulence contributions from 37 of 39 tested genes (95%) implicated by in vivo studies and 7 of 10 genes (70%) ascertained from in vitro selection, with one gene in common to the two strategies. Validated genes included 17 known virulence factors (39%) and 27 newly identified by our study (61%), some encoding functions not previously associated with macrophage pathogenesis. Most genes (80%) positively impacted macrophage invasion when disrupted, consistent with the phenotype readily arising from loss-of-function mutations in vivo. This work reveals genes and mechanisms that contribute to S. aureus infection of macrophages, highlights differences in mutations underlying convergent phenotypes arising from in vivo and in vitro systems, and supports the relevance of S. aureus macrophage pathogenesis during chronic respiratory infection in CF. Additional studies will be needed to illuminate the exact mechanisms by which implicated mutations affect their phenotypes.


Asunto(s)
Fibrosis Quística , Estudio de Asociación del Genoma Completo , Macrófagos , Infecciones Estafilocócicas , Staphylococcus aureus , Humanos , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidad , Macrófagos/microbiología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/genética , Infecciones Estafilocócicas/patología , Fibrosis Quística/microbiología , Mutación , Virulencia/genética , Factores de Virulencia/genética , Adaptación Fisiológica
9.
Nat Commun ; 15(1): 5953, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009586

RESUMEN

The intracellular bacterial pathogen Legionella pneumophila modulates host cell functions by secreting multiple effectors with diverse biochemical activities. In particular, effectors of the SidE family interfere with host protein ubiquitination in a process that involves production of phosphoribosyl ubiquitin (PR-Ub). Here, we show that effector LnaB converts PR-Ub into ADP-ribosylated ubiquitin, which is further processed to ADP-ribose and functional ubiquitin by the (ADP-ribosyl)hydrolase MavL, thus maintaining ubiquitin homeostasis in infected cells. Upon being activated by actin, LnaB also undergoes self-AMPylation on tyrosine residues. The activity of LnaB requires a motif consisting of Ser, His and Glu (SHxxxE) present in a large family of toxins from diverse bacterial pathogens. Thus, our study sheds light on the mechanisms by which a pathogen maintains ubiquitin homeostasis and identifies a family of enzymes capable of protein AMPylation.


Asunto(s)
Proteínas Bacterianas , Homeostasis , Legionella pneumophila , Ubiquitina , Ubiquitinación , Ubiquitina/metabolismo , Legionella pneumophila/metabolismo , Legionella pneumophila/patogenicidad , Humanos , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , ADP-Ribosilación , Interacciones Huésped-Patógeno , Adenosina Difosfato Ribosa/metabolismo , Enfermedad de los Legionarios/metabolismo , Enfermedad de los Legionarios/microbiología , Células HEK293 , Actinas/metabolismo , Células HeLa
11.
BMC Microbiol ; 24(1): 266, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39026145

RESUMEN

BACKGROUND: Legionella pneumophila is a Gram-negative intracellular bacillus and is the causative agent of a severe form of pneumonia called Legionnaires' disease which accounts for 2-9% of cases of community acquired pneumonia. It produces an extremely large protein belonging to the RTX (Repeats in ToXin) family, called RtxA, and we previously reported that RtxA is transported by a dedicated type 1 secretion system (T1SS) to the cell surface. RTX proteins have been shown to participate in the virulence or biofilm formation of various bacteria, the most studied models being the pore forming hemolysin A (HlyA) of Escherichia coli and the biofilm associated protein LapA of P. fluorescens. LapA localization depends on the enzymatic release by LapD/LapG complex activity. This study aimed to elucidate the dual localization (cell surface associated or released state) of L. pneumophila RTX protein (RtxA) and whether this released versus sequestered state of RtxA plays a role in L. pneumophila virulence. RESULTS: The hereby work reveals that, in vitro, LapG periplasmic protease cleaves RtxA N-terminus in the middle of a di-alanine motif (position 108-109). Consistently, a strain lacking LapG protease maintains RtxA on the cell surface, whereas a strain lacking the c-di-GMP receptor LapD does not exhibit cell surface RtxA because of its continuous cleavage and release, as in the LapA-D-G model of Pseudomonas fluorescens. Interestingly, our data point out a key role of RtxA in enhancing the infection process of amoeba cells, regardless of its location (embedded or released); therefore, this may be the result of a secondary role of this surface protein. CONCLUSIONS: This is the first experimental identification of the cleavage site within the RTX protein family. The primary role of RtxA in Legionella is still questionable as in many other bacterial species, hence it sounds reasonable to propose a major function in biofilm formation, promoting cell aggregation when RtxA is embedded in the outer membrane and facilitating biofilm dispersion in case of RtxA release. The role of RtxA in enhancing the infection process may be a result of its action on host cells (i.e., PDI interaction or pore-formation), and independently of its status (embedded or released).


Asunto(s)
Proteínas Bacterianas , Legionella pneumophila , Legionella pneumophila/patogenicidad , Legionella pneumophila/metabolismo , Legionella pneumophila/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Virulencia , Toxinas Bacterianas/metabolismo , Biopelículas/crecimiento & desarrollo , Enfermedad de los Legionarios/microbiología , Sistemas de Secreción Tipo I/metabolismo , Sistemas de Secreción Tipo I/genética , Membrana Celular/metabolismo
12.
Ann Clin Microbiol Antimicrob ; 23(1): 64, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39026348

RESUMEN

BACKGROUND: Infectious keratitis, a significant contributor to blindness, with fungal keratitis accounting for nearly half of cases, poses a formidable diagnostic and therapeutic challenge due to its delayed clinical presentation, prolonged culture times, and the limited availability of effective antifungal medications. Furthermore, infections caused by rare fungal strains warrant equal attention in the management of this condition. CASE PRESENTATION: A case of fungal keratitis was presented, where corneal scraping material culture yielded pink colonies. Lactophenol cotton blue staining revealed distinctive spore formation consistent with the Fusarium species. Further analysis using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) identified the causative agent as Fusarium proliferatum. However, definitive diagnosis of Pseudonectria foliicola infection was confirmed through ITS sequencing. The patient's recovery was achieved with a combination therapy of voriconazole eye drops and itraconazole systemic treatment. CONCLUSION: Pseudonectria foliicola is a plant pathogenic bacterium that has never been reported in human infections before. Therefore, ophthalmologists should consider Pseudonectria foliicola as a possible cause of fungal keratitis, as early identification and timely treatment can help improve vision in most eyes.


Asunto(s)
Antifúngicos , Infecciones Fúngicas del Ojo , Fusarium , Queratitis , Voriconazol , Humanos , Queratitis/microbiología , Queratitis/tratamiento farmacológico , Queratitis/diagnóstico , Antifúngicos/uso terapéutico , Infecciones Fúngicas del Ojo/microbiología , Infecciones Fúngicas del Ojo/tratamiento farmacológico , Infecciones Fúngicas del Ojo/diagnóstico , Voriconazol/uso terapéutico , Fusarium/aislamiento & purificación , Fusarium/efectos de los fármacos , Fusarium/patogenicidad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Itraconazol/uso terapéutico , Fusariosis/tratamiento farmacológico , Fusariosis/microbiología , Fusariosis/diagnóstico , Masculino , Córnea/microbiología , Córnea/patología , Femenino , Persona de Mediana Edad
13.
BMC Infect Dis ; 24(1): 711, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39030479

RESUMEN

BACKGROUND: Enterobacter cloacae complex (ECC) including different species are isolated from different human clinical samples. ECC is armed by many different virulence genes (VGs) and they were also classified among ESKAPE group by WHO recently. The present study was designed to find probable association between VGs and antibiotic susceptibility in different ECC species. METHODS: Forty-five Enterobacter isolates that were harvested from different clinical samples were classified in four different species. Seven VGs were screened by PCR technique and antibiotic susceptibility assessment was performed by disk-diffusion assay. RESULT: Four Enterobacter species; Enterobacter cloacae (33.3%), Enterobacter hormaechei (55.6%), Enterobacter kobei (6.7%) and Enterobacter roggenkampii (4.4%) were detected. Minimum antibiotic resistance was against carbapenem agents and amikacin even in MDR isolates. 33.3% and 13.3% of isolates were MDR and XDR respectively. The rpoS (97.8%) and csgD (11.1%) showed maximum and minimum frequency respectively. Blood sample isolated were highly virulent but less resistant in comparison to the other sample isolates. The csgA, csgD and iutA genes were associated with cefepime sensitivity. CONCLUSION: The fepA showed a predictory role for differentiating of E. hormaechei from other species. More evolved iron acquisition system in E. hormaechei was hypothesized. The fepA gene introduced as a suitable target for designing novel anti-virulence/antibiotic agents against E. hormaechei. Complementary studies on other VGs and ARGs and with bigger study population is recommended.


Asunto(s)
Antibacterianos , Enterobacter cloacae , Infecciones por Enterobacteriaceae , Pruebas de Sensibilidad Microbiana , Factores de Virulencia , Humanos , Antibacterianos/farmacología , Enterobacter cloacae/genética , Enterobacter cloacae/efectos de los fármacos , Enterobacter cloacae/aislamiento & purificación , Enterobacter cloacae/patogenicidad , Infecciones por Enterobacteriaceae/microbiología , Factores de Virulencia/genética , Virulencia/genética , Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana Múltiple/genética , Enterobacter/genética , Enterobacter/efectos de los fármacos , Enterobacter/aislamiento & purificación , Masculino , Femenino
14.
J Biosci ; 492024.
Artículo en Inglés | MEDLINE | ID: mdl-39046034

RESUMEN

Nitric oxide (NO) and iNOS are crucial host factors in innate immunity against intracellular pathogens. However, the role of NO in Mycobacterium tuberculosis (M. tb) infection in humans remains controversial, unlike in the murine model of TB. To investigate this, levels of NO, iNOS, and L-arginine, as well as the NOS2A gene polymorphism rs57234985 at the promoter region of NOS2A, were evaluated in pulmonary TB (PTB) patients and their household contacts (HHCs). Increased levels of NO and iNOS expression in HHCs indicated exposure to M. tb infection which was confirmed by higher levels of iNOS and NO in Mantouxpositive individuals. Furthermore, higher levels of arginine were detected in HHCs, suggesting its potential role in promoting optimal NO synthesis. PTB patients had higher levels of these analytes due to ongoing active infection. Interestingly, iNOS and NO levels were inversely related to bacterial burden, suggesting their antimicrobial role. NOS2A gene polymorphism was found to be associated with disease susceptibility, with the TT genotype linked to increased iNOS expression. To conclude, iNOS plays a crucial role in controlling early M. tb infection in HHCs by inducing optimal NO production with help of L-arginine. Further longitudinal studies are needed to better understand the role of these host factors upon disease activation.


Asunto(s)
Arginina , Inmunidad Innata , Mycobacterium tuberculosis , Óxido Nítrico Sintasa de Tipo II , Óxido Nítrico , Tuberculosis Pulmonar , Humanos , Óxido Nítrico/metabolismo , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/genética , Tuberculosis Pulmonar/microbiología , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/patogenicidad , Femenino , Masculino , Inmunidad Innata/genética , Adulto , Arginina/metabolismo , Persona de Mediana Edad , Composición Familiar , Predisposición Genética a la Enfermedad , Regiones Promotoras Genéticas/genética , Polimorfismo de Nucleótido Simple
15.
Mikrobiyol Bul ; 58(3): 225-238, 2024 Jul.
Artículo en Turco | MEDLINE | ID: mdl-39046206

RESUMEN

In recent years, as the paradigm of communication between cells has been clarified, the ability of bacteria to change their gene expression patterns in response to various extracellular signals has attracted great interest. In particular, intracellular and intercellular communication between bacterial populations, called quorum sensing (QS), is essential for coordinating physiological and genetic activities. QS studies are critical, particularly in elucidating the regulatory mechanisms of infectious processes in food-borne pathogens. Elucidating the QS mechanisms in Salmonella is effective in silencing the virulence factors in the fight against this bacterium. The aims of this study were; to create luxS gene mutants that play a vital role in the QS activity of Salmonella and to determine the effect of this mutation on the expression of virulence genes in the bacteria and to determine the impact of synthetic N-hexanoyl-homoserine lactone (C6HSL) on biofilm formation and AI-2 signaling pathway of Salmonella wild strain and luxS gene mutants. luxS gene mutants were constructed by recombining the gene region with the chloramphenicol gene cassette based on homologous region recombination. In the luxS mutants obtained in this way, the expression of eight different virulence genes (hilA, invA, inv, glgC, fimF, fliF, lpfA, gyrA), which have essential roles in Salmonella pathogenicity, was determined by quantitative real-time reverse transcriptase polymerase chain reaction (rRT-qPCR) method and compared with natural strains. As a result of these studies, it was determined that the expression of each gene examined was significantly reduced in luxS mutant strains. The relative AI-2 activities of Salmonella strains were analyzed depending on time. It was determined that the highest activity occurred at the fourth hour and the AI-2 activities of luxS mutants were reduced compared to the wild strain. Finally, it was determined that C6HSL increased the biofilm activity of Salmonella Typhimurium DMC4, SL1344 wild strains, and mutants, mainly at the 72nd hour. In conclusion, our results proved that C6HSL stimulated QS communication in all strains and increased biofilm of Salmonella formation and autoinducer activity. This situation determines that Salmonella responds to external signals by using QS systems. In addition, this research contributed to provide additional information on interspecies communication mechanisms to develop strategies to prevent biofilm formation of this pathogen.


Asunto(s)
Proteínas Bacterianas , Biopelículas , Liasas de Carbono-Azufre , Regulación Bacteriana de la Expresión Génica , Homoserina , Percepción de Quorum , Biopelículas/crecimiento & desarrollo , Liasas de Carbono-Azufre/genética , Virulencia , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Homoserina/análogos & derivados , Mutación , Factores de Virulencia/genética , 4-Butirolactona/análogos & derivados , 4-Butirolactona/metabolismo , Animales , Salmonella/patogenicidad , Salmonella/genética
16.
Sci Rep ; 14(1): 16843, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039119

RESUMEN

Trypanosoma evansi infection has started to become a wide spread phenomena around the camel-rearing areas of North Africa and the Middle East. The disease caused by trypanosomes is locally known as "Surra" and it can seriously impact not only the health of domestic animals but the local economy as well. After taking over the management of a farm containing approximately 700 camels, it was found that a large number were suffering from trypanosome infection and it was of the utmost importance to find the source of this infection. An extensive dive into the records and observations were initially made to identify the infected population. Under closer inspection it was found that the infection was limited mostly to female individuals that had undergone extended reproductive analysis or treatment. Blood samples were taken from each of the individuals for buffy coat test and blood smears. Among the total number of tested camels (n = 590), almost 40% were infected with trypanosomes. The number and percentage of infection correlate with the number of fertility and pregnancy treatments that the camels had undergone. The most severely infected group, underwent between 17 and 20 instances of treatment or tests, had an infection rate of almost 90%. The devastating effect of trypanosomiasis on camel pregnancy and birth were also verified with 61% of all abortions and 82% of all neonatal deaths coming from trypanosome infected individuals. These results clearly demonstrate how damaging iatrogenic infections of T. evansi can be and how simply they could have been prevented.


Asunto(s)
Camelus , Trypanosoma , Tripanosomiasis , Animales , Camelus/parasitología , Tripanosomiasis/transmisión , Tripanosomiasis/veterinaria , Tripanosomiasis/parasitología , Tripanosomiasis/epidemiología , Trypanosoma/patogenicidad , Femenino , Embarazo , Enfermedad Iatrogénica/epidemiología , Masculino
17.
Microbiologyopen ; 13(4): e1427, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39041461

RESUMEN

Human exposure to Vibrio vulnificus, a gram-negative, halophilic environmental pathogen, is increasing. Despite this, the mechanisms of its pathogenicity and virulence remain largely unknown. Each year, hundreds of infections related to V. vulnificus occur, leading to hospitalization in 92% of cases and a mortality rate of 35%. The infection is severe, typically contracted through the consumption of contaminated food or exposure of an open wound to contaminated water. This can result in necrotizing fasciitis and the need for amputation of the infected tissue. Although several genes (rtxA1, vvpE, and vvhA) have been implicated in the pathogenicity of this organism, a defined mechanism has not been discovered. In this study, we examine environmentally isolated V. vulnificus strains using a zebrafish model (Danio rerio) to investigate their virulence capabilities. We found significant variation in virulence between individual strains. The commonly used marker gene of disease-causing strains, vcgC, did not accurately predict the more virulent strains. Notably, the least virulent strain in the study, V. vulnificus Sept WR1-BW6, which tested positive for vcgC, vvhA, and rtxA1, did not cause severe disease in the fish and was the only strain that did not result in any mortality. Our study demonstrates that virulence varies greatly among different environmental strains and cannot be accurately predicted based solely on genotype.


Asunto(s)
Vibriosis , Vibrio vulnificus , Pez Cebra , Vibrio vulnificus/patogenicidad , Vibrio vulnificus/genética , Vibrio vulnificus/aislamiento & purificación , Animales , Pez Cebra/microbiología , Virulencia/genética , Vibriosis/microbiología , Factores de Virulencia/genética , Modelos Animales de Enfermedad , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Humanos , Microbiología Ambiental
18.
J Cell Mol Med ; 28(14): e18550, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39042561

RESUMEN

Endometritis is one of the important causes of infertility. Puerarin (PU) can inhibit oxidative stress and reduce inflammation; however, it is unclear whether PU has a protective effect on the endometritis. In our study, we used Staphylococcus aureus to induce mouse endometritis. The PU group (100 mg/kg PU) and the S. aureus + PU group received daily intraperitoneal injection of PU (25, 50 or 100 mg/kg PU). The results showed that S. aureus significantly increased the levels of MPO, TNF-α, IL-1ß and IL-6 in uterine tissue, and increased the expression of p-p65 and p-IκBα proteins in uterine tissue to induce endometritis in mice (p < 0.05). Furthermore, it has been found that S. aureus promotes the occurrence of ferroptosis by reducing GSH and ATP content, increasing MDA and iron content and reducing GPX4 and SLC7A11 protein expression levels (p < 0.05). S. aureus significantly increase the expression of NLRP3, ASC, caspase-1 and P2X7 proteins in uterine tissue (p < 0.05). However, PU obviously reduced the inflammatory response and reversed the changes of ferroptosis and the expression of P2X7 receptor/NLRP3 pathway associated proteins of the uterus induced by S. aureus (p < 0.05). Taken together, these findings emphasize the protective effect of PU on endometritis by regulating the P2X7 receptor/NLRP3 signalling pathway and inhibiting ferroptosis.


Asunto(s)
Endometritis , Ferroptosis , Isoflavonas , Proteína con Dominio Pirina 3 de la Familia NLR , Receptores Purinérgicos P2X7 , Transducción de Señal , Infecciones Estafilocócicas , Staphylococcus aureus , Animales , Femenino , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Isoflavonas/farmacología , Isoflavonas/uso terapéutico , Ferroptosis/efectos de los fármacos , Staphylococcus aureus/patogenicidad , Endometritis/metabolismo , Endometritis/microbiología , Endometritis/tratamiento farmacológico , Endometritis/patología , Transducción de Señal/efectos de los fármacos , Ratones , Receptores Purinérgicos P2X7/metabolismo , Infecciones Estafilocócicas/metabolismo , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/patología , Útero/metabolismo , Útero/patología , Útero/efectos de los fármacos , Útero/microbiología , Estrés Oxidativo/efectos de los fármacos
19.
Clin Exp Med ; 24(1): 168, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39052148

RESUMEN

Cancers associated with pathogen infections are gradually becoming important threats to human health globally, and it is of great significance to study the mechanisms of pathogen carcinogenesis. Current mechanistic studies rely on animal and two-dimensional (2D) cell culture models, but traditional methods have been proven insufficient for the rapid modeling of diseases caused by new pathogens. Therefore, research focus has shifted to organoid models, which can replicate the structural and genetic characteristics of the target tissues or organs in vitro, providing new platforms for the study of pathogen-induced oncogenic mechanisms. This review summarizes the application of organoid technology in the studies of four pathogen-associated cancers: gastric cancer linked to Helicobacter pylori, liver cancer associated with hepatitis B virus or hepatitis C virus, colorectal cancer caused by Escherichia coli, and cervical cancer related to human papillomavirus. This review also proposes several limitations of organoid technology to optimize organoid models and advance the treatment of cancer associated with pathogen infections in the future.


Asunto(s)
Organoides , Humanos , Organoides/patología , Neoplasias/patología , Helicobacter pylori/patogenicidad , Infecciones por Helicobacter/complicaciones , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/virología , Neoplasias del Cuello Uterino/virología , Neoplasias del Cuello Uterino/patología , Neoplasias Gástricas/patología , Neoplasias Gástricas/virología , Neoplasias Gástricas/microbiología , Infecciones por Papillomavirus/virología , Infecciones por Papillomavirus/complicaciones , Neoplasias Colorrectales/patología , Femenino , Escherichia coli/patogenicidad
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