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1.
Cell Mol Neurobiol ; 43(2): 785-795, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35334011

RESUMEN

Ureaplasma species (spp.) are considered commensals of the adult genitourinary tract, but have been associated with chorioamnionitis, preterm birth, and invasive infections in neonates, including meningitis. Data on mechanisms involved in Ureaplasma-driven neuroinflammation are scarce. The present study addressed brain inflammatory responses in preterm lambs exposed to Ureaplasma parvum (UP) in utero. 7 days after intra-amniotic injection of UP (n = 10) or saline (n = 11), lambs were surgically delivered at gestational day 128-129. Expression of inflammatory markers was assessed in different brain regions using qRT-PCR and in cerebrospinal fluid (CSF) by multiplex immunoassay. CSF was analyzed for UP presence using ureB-based real-time PCR, and MRI scans documented cerebral white matter area and cortical folding. Cerebral tissue levels of atypical chemokine receptor (ACKR) 3, caspases 1-like, 2, 7, and C-X-C chemokine receptor (CXCR) 4 mRNA, as well as CSF interleukin-8 protein concentrations were significantly increased in UP-exposed lambs. UP presence in CSF was confirmed in one animal. Cortical folding and white matter area did not differ among groups. The present study confirms a role of caspases and the transmembrane receptors ACKR3 and CXCR4 in Ureaplasma-driven neuroinflammation. Enhanced caspase 1-like, 2, and 7 expression may reflect cell death. Increased ACKR3 and CXCR4 expression has been associated with inflammatory central nervous system (CNS) diseases and impaired blood-brain barrier function. According to these data and previous in vitro findings from our group, we speculate that Ureaplasma-induced caspase and receptor responses affect CNS barrier properties and thus facilitate neuroinflammation.


Asunto(s)
Corioamnionitis , Nacimiento Prematuro , Recién Nacido , Embarazo , Humanos , Femenino , Ovinos , Animales , Enfermedades Neuroinflamatorias , Ureaplasma/metabolismo , Caspasas/metabolismo , Líquido Amniótico/metabolismo
2.
Int J Med Microbiol ; 312(3): 151552, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35231822

RESUMEN

Helicobacter pylori infection is strongly associated with gastritis, gastroduodenal ulcer disease and gastric carcinoma. The virulence of H. pylori strains increases with the presence of the pathogenicity island PAI, which encodes a Type 4 Secretion System and the oncoprotein CagA. Two major CagA types can be distinguished by differences in the repetitive EPIYA region in the C-terminal sequence; the more virulent East Asian CagA type with EPIYA-A, -B, and -D motifs and the Western CagA type with EPIYA-A, -B, and C motifs, the virulence of which is associated with the multitude of EPIYA-C motifs. In this study, the cagA gene was characterized in H. pylori strains isolated from Mongolians suffering from gastritis (80%) or ulcer (20%). The EPIYA region of 53 isolates was determined by PCR-amplification of overlapping cagA regions and subsequent Sanger sequencing. Only one H. pylori isolate carried the East Asian type (ABD) and 52 isolates the Western type of CagA, thereof 30 the EPIYA type ABC, 19 the ABCC type and one each of type ABCCCC, AAABC and AAAAB. An amino acid exchange from EPIYA-B to EPIYT-B was predominantly found in CagA proteins in strains with < 2 EPIYA-C copies (n = 25/32; p = 0.015) including the two EPIYA-A enriched CagA proteins, which have not been described to date. Due to the amino acid triplet preceding the EPIYA motif and strength of predicted phosphorylation, the multiple EPIYA-A motifs A2, A3 and A4 were shown to cluster with EPIYA-B and EPIYT-B with the unique feature of amino acid E in position - 4 to Y of EPIYA. It has been described that tyrosine-phosphorylated EPIYA-A and -B motifs counteract the EPIYA-C-driven signaling towards host cell transformation and malignancy. Thus, Mongolian H. pylori strains carrying CagA proteins not only with a few EPIYA-C segments but also with multiplied EPIYA-A segments are probably less virulent; a thesis that needs further investigation at the protein level.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Secuencias de Aminoácidos , Antígenos Bacterianos/genética , Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/metabolismo , Humanos , Mongolia
3.
Med Mycol ; 59(11): 1101-1113, 2021 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-34379780

RESUMEN

Fungal respiratory tract colonization is a common finding in patients with hematologic neoplasms due to immunosuppression inherent in the diseases and exacerbated by therapy. This greatly increases the risk of fungal infections of the lungs, which is associated with significant mortality. Therefore, reliable diagnostic methods with rapidly available results are needed to administer adequate antifungal therapy. We have established an improved method for fungal DNA extraction and amplification that allows simultaneous detection of fungal families based on a set of multiplexed real-time PCR reactions (fuPCR). We analyzed respiratory rinses and blood of 94 patients with hematological systemic diseases by fuPCR and compared it with the results of culture and serological diagnostic methods. 40 healthy subjects served as controls. Regarding Candida species, the highest prevalence resulted from microbiological culture of respiratory rinses and from detection of antibodies in blood serum in patients (61 and 47%, respectively) and in the control group (29 and 51%, respectively). Detection of other pathogenic yeasts, such as Cryptococcus and Trichosporon, and molds, such as Fusarium, was only possible in patients by fuPCR from both respiratory rinses and whole blood and serum. These fungal species were found statistically significantly more frequent in respiratory rinses collected from patients after myeloablative therapy for stem cell transplantation compared to samples collected before treatment (P < 0.05i). The results show that fuPCR is a valuable complement to culturing and its inclusion in routine mycological diagnostics might be helpful for early detection of pathophysiologically relevant respiratory colonization for patients with hematologic neoplasms.


We validated a set of PCR reactions (fuPCR) for use in routine diagnostic. In contrast to culture and serological methods, only by fuPCR pathogenic yeasts (Cryptococcus and Trichosporon) and molds (Aspergillus and Fusarium) were detected in respiratory rinses and blood of hematological patients.


Asunto(s)
Cryptococcus/aislamiento & purificación , Fusarium/aislamiento & purificación , Neoplasias Hematológicas/complicaciones , Micosis/diagnóstico , Micosis/etiología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Trichosporon/aislamiento & purificación , Cryptococcus/genética , Técnicas y Procedimientos Diagnósticos , Femenino , Fusarium/genética , Voluntarios Sanos , Humanos , Masculino , Micosis/genética , Trichosporon/genética
4.
Int J Med Microbiol ; 310(6): 151443, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32862838

RESUMEN

In immunocompromised patients a colonisation with fungi carries the risk to develop serious invasive fungal infection. An early detection is therefore important, but not optimal hitherto. Fortunately, molecular genetic methods have increased the sensitivity of fungal detection and limited the time, until results are available. However, their success depends on an efficient extraction of genomic DNA from the fungal cell in the given diagnostic specimen. To improve the routine DNA preparation method for yeasts and moulds, the impact of bead beating on fungal DNA release was evaluated. PBS, blood and respiratory rinse were spiked with Candida glabrata or Aspergillus fumigatus. DNA was extracted by mechanical bead beating in addition to the different steps of the DNA preparation protocol, which comprised liquid nitrogen treatment, proteinase K digestion and DNA isolation using the EZ1 DNA Tissue Kit and Workstation. In every method variant tested, treatment with liquid nitrogen did not improve the DNA release. Bead beating once followed by proteinase K digestion and EZ1-work-up led to the highest DNA release from fungus, spiked in PBS, and increased the extracted DNA amount of C. glabrata about 100-fold and of A. fumigatus about 10-fold in relation to sole EZ1-work-up. In fungus-spiked respiratory rinse and blood, highest increase in DNA release was measured after triple bead beating with simultaneous proteinase K digestion. Fungal DNA release of C. glabrata increased for >100-fold in respiratory rinse and for >1000-fold in blood and of A. fumigatus for >10-fold in respiratory rinse and about 5- to 10-fold in blood. The data of this study clearly demonstrate that preparation of fungal DNA from human specimens is optimized by introduction of a bead beating step to the conventional DNA-preparation method without the necessity of a liquid nitrogen step.


Asunto(s)
ADN de Hongos/aislamiento & purificación , Hongos , Técnicas Microbiológicas/métodos , Aspergillus fumigatus , Candida glabrata , Hongos/genética , Humanos
5.
Cytokine ; 105: 45-48, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29455108

RESUMEN

Generally regarded as commensal bacteria, the pathogenicity of Ureaplasma has often been considered low. Controversy remains concerning the clinical relevance of Ureaplasma infection in the pathogenesis of inflammation-related morbidities. Recently, we demonstrated Ureaplasma-driven pro-inflammatory cytokine responses in human monocytes in vitro. We hypothesized that Ureaplasma may induce further inflammatory mediators. Using qRT-PCR and multi-analyte immunoassay, we assessed the expression of granulocyte-colony stimulating factor (G-CSF), vascular endothelial growth factor (VEGF), intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in term neonatal and adult monocytes exposed to Ureaplasma urealyticum serovar 8 (Uu8) and U. parvum serovar 3 (Up3). Ureaplasma significantly induced VEGF mRNA in neonatal (Up3: p < 0.05, versus broth control) and adult monocytes (Uu8: p < 0.05) as well as ICAM-1 mRNA in neonatal cells (p < 0.05 each). As far as protein expression was concerned, Up3 stimulated VEGF release in both monocyte subsets (p < 0.01) and enhanced secretion of ICAM-1 protein in neonatal monocytes (p < 0.05). In adult cells, ICAM-1 protein release was increased upon exposure to both isolates (Uu8: p < 0.05, Up3: p < 0.01). Ureaplasma-induced responses did not significantly differ from corresponding levels mediated by E. coli lipopolysaccharide (LPS). The stimulatory effects were dose-dependent. Ureaplasma infection, on the contrary, did not affect G-CSF and VCAM-1 expression. Of note, co-infection of LPS-primed neonatal monocytes with Ureaplasma enhanced LPS-induced ICAM-1 release (Uu8: p < 0.05). Our results confirm Ureaplasma-driven pro-inflammatory activation of human monocytes in vitro, demonstrating a differential modulation of growth factors and cell adhesion molecules, that might promote unbalanced monocyte responses and adverse immunomodulation.


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Monocitos/metabolismo , Ureaplasma/aislamiento & purificación , Ureaplasma/fisiología , Adulto , Moléculas de Adhesión Celular/genética , Humanos , Recién Nacido , Péptidos y Proteínas de Señalización Intercelular/genética , Lipopolisacáridos/farmacología , Monocitos/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo
6.
Parasitol Res ; 117(3): 841-847, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29368037

RESUMEN

In Europe, up to 90% of isolated Trichomonas vaginalis strains are naturally infected with Mycoplasma hominis, a facultative pathogen of the human genital tract. The consequences of this endosymbiosis are not yet well understood. The aim of the current study was to evaluate the impact of natural and artificial infections with M. hominis on the RNA expression levels of metronidazole susceptibility-associated genes of T. vaginalis. Three T. vaginalis strains (TVSS10-, TVSS25-, G3) without M. hominis, as well as the same strains naturally (TVSS10+, TVSS25+) and artificially (G3-MhSS25, TVSS25-MhSS25) infected with M. hominis, were investigated for their expression profiles of three genes associated with metronidazole resistance (ferredoxin, flavin reductase 1 and pyruvate:ferredoxin oxidoreductase). The minimal inhibitory concentrations (MICs) of metronidazole were evaluated for all combinations and the respective M. hominis-free T. vaginalis strains were used as controls. The sole presence of M. hominis led to a down-regulation of metronidazole susceptibility-associated genes in all T. vaginalis strains tested. Interestingly, the effect was more prominent in the artificial symbioses. Moreover, a twofold enhancement of metronidazole tolerability was observed in three infected T. vaginalis strains, compared to the respective strains without M. hominis. In conclusion, M. hominis had an impact on gene expression in all T. vaginalis strains and on metronidazole MIC in all but one strain tested.


Asunto(s)
Mycoplasma hominis/fisiología , Trichomonas vaginalis/genética , Trichomonas vaginalis/microbiología , Antiprotozoarios/farmacología , Regulación hacia Abajo , Resistencia a Medicamentos/efectos de los fármacos , Europa (Continente) , Regulación de la Expresión Génica , Metronidazol/farmacología , Pruebas de Sensibilidad Microbiana , Simbiosis , Trichomonas vaginalis/efectos de los fármacos
7.
J Shoulder Elbow Surg ; 27(5): 771-776, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29361412

RESUMEN

HYPOTHESIS: We hypothesized that the prevalence of Propionibacterium acnes in patients undergoing primary shoulder arthroscopy is equal in the glenohumeral space compared with the subacromial space. METHODS: Patients aged 18 years or older with shoulder arthroscopies were included. The exclusion criteria were prior shoulder operations, complete rotator cuff tears, systemic inflammatory diseases, tumors, shoulder injections within 6 months of surgery, and antibiotic therapy within 14 days preoperatively. After standardized skin disinfection with Kodan Tinktur Forte Gefärbt, a skin swab was taken at the posterior portal. Arthroscopy was performed without cannulas, prospectively randomized to start either in the glenohumeral space or in the subacromial space, with direct harvesting of a soft-tissue biopsy specimen. Sample cultivation was conducted according to standardized criteria for bone and joint aspirate samples and incubated for 14 days. Matrix-assisted laser desorption-ionization time-of-flight spectrometry was used for specimen identification in positive culture results. RESULTS: The study prospectively included 115 consecutive patients with normal C-reactive protein levels prior to surgery (54.8% men; mean age, 47.2 ± 14.6 years). P acnes was detected on the skin after disinfection in 36.5% of patients, in the glenohumeral space in 18.9%, and in the subacromial space in 3.5% (P = .016). CONCLUSION: The prevalence of P acnes is significantly higher in the glenohumeral space compared with the subacromial space in primary shoulder arthroscopies. The results do not confirm the contamination theory but also cannot clarify whether P acnes is a commensal or enters the joint hematologically or even lymphatically or via an unknown pathway. Despite standardized surgical skin disinfection, P acnes can be detected in skin swab samples in more than one-third of patients.


Asunto(s)
Acromion/microbiología , Artroscopía , Propionibacterium acnes/aislamiento & purificación , Articulación del Hombro/microbiología , Articulación del Hombro/cirugía , Piel/microbiología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Adulto Joven
8.
Int J Med Microbiol ; 307(4-5): 209-215, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28495466

RESUMEN

Infections with multi-resistant bacteria, such as Methicillin-resistant Staphylococcus aureus (MRSA), represent a world-wide health-care problem. The original MRSA Screening TaqMan PCR was based on the detection of the SCCmec-orfX-junction as described by the group of Huletsky in 2004. In the recent years, this assay increasingly failed to detect new MRSA variants in swab specimens. In this work, we analyzed the usefulness of 17 additional SCCmec primers to increase PCR sensitivity by testing 290 collected samples with negative PCR results and positive MRSA culture in a retrospective analysis, and 380 samples of the daily routine diagnostics. Sequencing of the PCR products revealed that locally new MRSA variants became detectable by nine of these forward primers. Four primers were solely responsible for the detection of 85.4% (117/123) of the PCR products: F13 (n=76), F11 (n=6), F14 (n=15) and F25 (n=8). These four primers were integrated in the Screening PCR and the novel primer collection was validated by testing 71 MRSA isolates, which covered SCCmec types I to VI, 50 MSSA isolates and 100 swab specimens. The sensitivity of MRSA Screening PCR increased from 93% to 98.6% without affecting the detection of the common MRSA strains. Phylogenetic analysis of the PCR products suggests that the adapted MRSA Screening PCR is able to detect SCCmec types I-X, including CA- and LA-MRSA variants by the SCCmec primers F11 and F25.


Asunto(s)
Cartilla de ADN , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Reacción en Cadena de la Polimerasa , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Genes Bacterianos , Humanos , Filogenia , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Análisis de Secuencia de ADN , Manejo de Especímenes
9.
Int J Med Microbiol ; 306(8): 611-623, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27765533

RESUMEN

Fungal infections are recognized in an increasing number of patients with immunological deficits and are associated with high rates of mortality (Brown et al., 2012a). In this pilot-study, a rapid Real time PCR (fuPCR) was designed for the detection and differentiation of fungal pathogens in clinical specimens of haematological patients. The fuPCR, targeting the internal transcribed spacer region 2 (ITS2) of rDNA region, is comprised of seven multiplex reactions, which were shown to be specific and sensitive for a comprehensive spectrum of clinically relevant fungal species. This was validated by testing respective fungal DNAs in each fuPCR reaction and 28 respiratory samples of fungal pneumonia-proven patients. Clinical sample sets of throat swab, EDTA-blood and blood sera from 50 patients with severe haematological malignancies, including haematopoietic stem cell transfer (HSCT), and samples from 30 healthy individuals were then analysed. In a first step, 198 samples of immunosuppressed patients were solely examined by fuPCR; and 50.8% (33/65) respiratory swabs, 4.8% (3/63) EDTA blood samples and 1.4% (1/70) blood serum samples were tested positive. In a second step, 56 respiratory samples of immunosuppressed patients and 30 of healthy individuals were simultaneously analysed by fuPCR and standard cultivation techniques. By both methods 30.4% (17/56) swabs of the immunocompromised patients were tested positive, 37.5% (21/56) were tested negative and 32.1% (18/56) were tested fuPCR positive and culture negative. In analysing the blood samples of the immunocompromised patients 5.4% (3/56) EDTA blood samples and 16.1% (9/56) sera samples were tested fuPCR-positive, whereas all samples of 30 healthy individuals with no signs of immunological deficits were tested negative by fuPCR. 38.9% (14/36) of the fungi detected in respiratory samples of the immunosuppressed patients, belonged to Candida spp., 47.2% (17/36) to Saccharomyces spp., 5.6% (2/36) to Cladosporium spp. and 8.3% (3/36) to Alternaria spp., whereas cultivation only identified Candida spp. (10/17) and Saccharomyces spp. (7/17). In this pilot study a novel fuPCR assay was developed and validated for the simultaneous and comprehensive detection of fungal pathogens in clinical respiratory specimens of haematological patients. Future work will focus on the validation of the blood-stream detected fungi in pathogenicity of these patients.


Asunto(s)
Hongos/aislamiento & purificación , Neoplasias Hematológicas/complicaciones , Huésped Inmunocomprometido , Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena de la Polimerasa Multiplex/métodos , Micosis/diagnóstico , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adulto , Anciano , Anciano de 80 o más Años , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Femenino , Hongos/clasificación , Hongos/genética , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto
10.
Clin Oral Investig ; 20(4): 841-7, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26297129

RESUMEN

OBJECTIVE: The aim of this study was to investigate the oral parameters that influence the caries risk and risk of developing periodontal disease in children with phenylketonuria (PKU) and type 1 diabetes compared to healthy children. MATERIAL AND METHODS: Two hundred and thirty-eight children between the ages of 3 and 18 years were recruited in the PKU, diabetes and healthy group. The decayed, missing and filled surfaces (dmfs/DMFS) index, papillary bleeding index (PBI) and the Silness & Löe Index were assessed. Quantitative real-time polymerase chain reaction (PCR) was used for the detection of Streptococcus mutans (Sm), Lactobacillus casei (Lca), Lactobacillus species (Lac), Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg) and Tannerella forsythensis (Tf). RESULTS: A statistically significant difference in the dmfs index value was found between the three groups. The mean dmfs index value for the PKU children (4.18) was found to be relatively high. Comparing the three groups, diabetics showed statistically significant higher values for the Silness and Löe Index. Comparing the diabetics to just the healthy children, the diabetics revealed a small statistically significant difference in the PBI score. A statistically significant difference was found between Lac, Lca and Pg in the three groups. Counts of Lac were the lowest in the PKU children. The diabetics showed the highest counts of Lca but lowest for Pg. CONCLUSIONS: Comparing the three groups, children with PKU revealed a higher caries experience in their primary dentition. While the diabetic children showed a lower one in their primary dentition, they were found to possess a slightly higher risk of developing periodontal disease. CLINICAL RELEVANCE: It is proposed that both groups of child patients be encouraged to seek early dental advice and be incorporated in a meticulous prevention programme.


Asunto(s)
Caries Dental/complicaciones , Diabetes Mellitus Tipo 1/complicaciones , Fenilcetonurias/complicaciones , Adolescente , Niño , Preescolar , Índice CPO , Femenino , Humanos , Masculino , Streptococcus mutans
11.
J Clin Microbiol ; 53(12): 3938-41, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26468503

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) screening using real-time PCR has decreased in sensitivity due to the emergence of variant staphylococcal cassette chromosome mec element (SCCmec) types. We have designed and validated a novel SCCmec XI primer, which enables for the first time the rapid detection of mecC-harboring MRSA directly from nasopharyngeal swabs without prior cultivation.


Asunto(s)
Técnicas Bacteriológicas/métodos , Cartilla de ADN/genética , Tamizaje Masivo/métodos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Técnicas de Diagnóstico Molecular/métodos , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/microbiología , Portador Sano/diagnóstico , Portador Sano/microbiología , Humanos , Staphylococcus aureus Resistente a Meticilina/genética , Nasofaringe/microbiología
12.
Sci Rep ; 14(1): 4068, 2024 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-38374282

RESUMEN

The gut microbiome is a diverse ecosystem, dominated by bacteria; however, fungi, phages/viruses, archaea, and protozoa are also important members of the gut microbiota. Exploration of taxonomic compositions beyond bacteria as well as an understanding of the interaction between the bacteriome with the other members is limited using 16S rDNA sequencing. Here, we developed a pipeline enabling the simultaneous interrogation of the gut microbiome (bacteriome, mycobiome, archaeome, eukaryome, DNA virome) and of antibiotic resistance genes based on optimized long-read shotgun metagenomics protocols and custom bioinformatics. Using our pipeline we investigated the longitudinal composition of the gut microbiome in an exploratory clinical study in patients undergoing allogeneic hematopoietic stem cell transplantation (alloHSCT; n = 31). Pre-transplantation microbiomes exhibited a 3-cluster structure, characterized by Bacteroides spp. /Phocaeicola spp., mixed composition and Enterococcus abundances. We revealed substantial inter-individual and temporal variabilities of microbial domain compositions, human DNA, and antibiotic resistance genes during the course of alloHSCT. Interestingly, viruses and fungi accounted for substantial proportions of microbiome content in individual samples. In the course of HSCT, bacterial strains were stable or newly acquired. Our results demonstrate the disruptive potential of alloHSCTon the gut microbiome and pave the way for future comprehensive microbiome studies based on long-read metagenomics.


Asunto(s)
Microbioma Gastrointestinal , Trasplante de Células Madre Hematopoyéticas , Microbiota , Humanos , Microbioma Gastrointestinal/genética , Microbiota/genética , Bacterias/genética , Antibacterianos , Hongos/genética , ADN Ribosómico , Metagenómica/métodos
14.
Antimicrob Agents Chemother ; 57(10): 5162-5, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23877696

RESUMEN

Since the first isolation in 2002, the metallo-ß-lactamase GIM-1 has not been detected outside Germany. The data presented here, for 50 clinical blaGIM-1-positive isolates, including Pseudomonas spp. and Enterobacteriaceae (Enterobacter cloacae, Klebsiella oxytoca, Serratia marcescens, Escherichia coli, and Citrobacter freundii), collected between 2007 and 2012 at the original site in an ongoing outbreak, demonstrate a diverse genetic background and dissemination of the gene conferring resistance to enteric bacteria.


Asunto(s)
Enterobacteriaceae/enzimología , Enterobacteriaceae/genética , Pseudomonas/enzimología , beta-Lactamasas/metabolismo , Integrones/genética , Datos de Secuencia Molecular , Pseudomonas/genética , beta-Lactamasas/genética
15.
Microorganisms ; 11(6)2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37375093

RESUMEN

Bacterial virulence, persistence and defence are affected by epigenetic modifications, including DNA methylation. Solitary DNA methyltransferases modulate a variety of cellular processes and influence bacterial virulence; as part of a restriction-modification (RM) system, they act as a primitive immune system in methylating the own DNA, while unmethylated foreign DNA is restricted. We identified a large family of type II DNA methyltransferases in Metamycoplasma hominis, comprising six solitary methyltransferases and four RM systems. Motif-specific 5mC and 6mA methylations were identified with a tailored Tombo analysis on Nanopore reads. Selected motifs with methylation scores >0.5 fit with the gene presence of DAM1 and DAM2, DCM2, DCM3, and DCM6, but not for DCM1, whose activity was strain-dependent. The activity of DCM1 for CmCWGG and of both DAM1 and DAM2 for GmATC was proven in methylation-sensitive restriction and finally for recombinant rDCM1 and rDAM2 against a dam-, dcm-negative background. A hitherto unknown dcm8/dam3 gene fusion containing a (TA) repeat region of varying length was characterized within a single strain, suggesting the expression of DCM8/DAM3 phase variants. The combination of genetic, bioinformatics, and enzymatic approaches enabled the detection of a huge family of type II DNA MTases in M. hominis, whose involvement in virulence and defence can now be characterized in future work.

16.
HLA ; 102(1): 28-43, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36932816

RESUMEN

Accurate and comprehensive immunogenetic reference panels are key to the successful implementation of population-scale immunogenomics. The 5Mbp Major Histocompatibility Complex (MHC) is the most polymorphic region of the human genome and associated with multiple immune-mediated diseases, transplant matching and therapy responses. Analysis of MHC genetic variation is severely complicated by complex patterns of sequence variation, linkage disequilibrium and a lack of fully resolved MHC reference haplotypes, increasing the risk of spurious findings on analyzing this medically important region. Integrating Illumina, ultra-long Nanopore, and PacBio HiFi sequencing as well as bespoke bioinformatics, we completed five of the alternative MHC reference haplotypes of the current (GRCh38/hg38) build of the human reference genome and added one other. The six assembled MHC haplotypes encompass the DR1 and DR4 haplotype structures in addition to the previously completed DR2 and DR3, as well as six distinct classes of the structurally variable C4 region. Analysis of the assembled haplotypes showed that MHC class II sequence structures, including repeat element positions, are generally conserved within the DR haplotype supergroups, and that sequence diversity peaks in three regions around HLA-A, HLA-B+C, and the HLA class II genes. Demonstrating the potential for improved short-read analysis, the number of proper read pairs recruited to the MHC was found to be increased by 0.06%-0.49% in a 1000 Genomes Project read remapping experiment with seven diverse samples. Furthermore, the assembled haplotypes can serve as references for the community and provide the basis of a structurally accurate genotyping graph of the complete MHC region.


Asunto(s)
Antígenos de Histocompatibilidad Clase II , Complejo Mayor de Histocompatibilidad , Humanos , Haplotipos , Alelos , Antígenos de Histocompatibilidad Clase II/genética , Complejo Mayor de Histocompatibilidad/genética , Antígenos HLA/genética , Antígenos HLA-C/genética
17.
PLoS One ; 17(7): e0270962, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35802644

RESUMEN

OBJECTIVE: To characterize a potential pathogenic role of Mycoplasma salivarium and bacterial co-detection patterns on different implant augmentation types. MATERIAL AND METHODS: 36 patients were non-randomly assigned to autogenous lateral alveolar ridge augmentation with either cortical autogenous bone blocks, or healthy autogenous tooth roots or non-preservable teeth. Mucosal inflammation was assessed by probing pocket depth (PD) at all sampling sites and by bleeding on probing (BOP) in a subset of sampling sites, and standardized biofilm samples were obtained from the submucosal peri-implant sulcus and sulcus of a contralateral tooth at two times (t1 after implant placement; t2 after six months). Seven bacterial species were quantified using Taqman PCR. RESULTS: Mucosal inflammation did not differ between augmentation groups, but peri-implant sulci showed increased abundance of M. salivarium after augmentation with autogenous tooth roots lasting for at least six months (t1 p = 0.05, t2 p = 0.011). In M. salivarium-positive samples, Tannerella forsythia was correlated with PD (R = 0.25, p = 0.035) This correlation was not observed in M. salivarium-negative samples. Compared to all other samples, PD was deeper in co-detection (i.e., simultaneous M. salivarium and T. forsythia) positive samples (p = 0.022). No association of single or co-detection of bacteria with BOP was observed. CONCLUSION: Presence of M. salivarium in peri-implant sulci varies with augmentation method and is associated with increased PD but not BOP. A potential causal role of M. salivarium in inflammation through a mechanism involving co-presence of T. forsythia requires further study.


Asunto(s)
Aumento de la Cresta Alveolar , Mycoplasma salivarium , Aumento de la Cresta Alveolar/métodos , Trasplante Óseo/métodos , Humanos , Inflamación , Tannerella forsythia
18.
Antibiotics (Basel) ; 11(9)2022 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-36139958

RESUMEN

A patient with oral squamous cell carcinoma (OSCC) underwent complex surgical tumor therapy, including the reconstruction of soft tissues using a radial forearm flap. Due to venous congestion that could only partly be resolved by revision surgery, leech therapy was started on the second postoperative day. The patient developed pneumonia and sepsis and died as a result of septic shock, despite having received targeted broad-spectrum antibiotic therapy since day 5. Aeromonas spp. were cultured from both the patient's specimens and unused leeches. Biochemical identification and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) yielded inconsistent identification results. Finally, microbiological identification of Aeromonas spp. was performed via 16S rDNA sequencing and use of the basic local alignment search tool (BLAST), and strains from both the patient and the leeches were identified as Aeromonas veronii. Aeromonas spp. strains derived from the patient and leeches and independent laboratory strains were submitted to randomly amplified polymorphic DNA (RAPD) subtyping. RAPD of A. veronii strains from both sources revealed an identical pattern, strongly suggesting the transmission of A. veronii from the leeches to the patient. Physicians should be aware of the potential for severe lethal infections as a fatal side-effect of leech therapy in critically ill patients, which should be addressed using antibiotic prophylaxis.

19.
BMC Microbiol ; 11: 185, 2011 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-21854595

RESUMEN

BACKGROUND: In Mycoplasma hominis, a facultative human pathogen of the human genital tract, OppA, the substrate-binding domain of the oligopeptide permease, is a multifunctional protein involved in nutrition uptake, cytoadhesion and hydrolysis of extracellular ATP. RESULTS: To map the function-related protein regions the ATPase activity and adhesive behavior of OppA mutants were analyzed. Mutations of the Walker BA motifs resulted in an inhibition of up to 8% of the OppA ATPase activity, whereas deletion of the N-terminal CS1 or the CS2 region, structural motifs that are conserved in bacterial OppA proteins, reduced ATPase activity to 60% and deletion of CS3, the third conserved region adjacent to the Walker B motif led to a reduction to 42% ATPase activity. Interestingly, adhesion of the OppA mutants to immobilized HeLa cells demonstrated that two distal regions are mainly involved in adherence of OppA: the CS1 region, deletion of which led to 35% of the cytoadhesion, and the Walker BA with the adjacent upstream region CS3, deletion of which led to 25% of the cytoadhesion. The influence of the ATPase activity on the adherence of M. hominis to HeLa cells was confirmed by the use of ATPase inhibitors which reduced mycoplasmal cytoadhesion to 50%. CONCLUSIONS: These findings suggest that the OppA-mediated cytoadherence of Mycoplasma hominis depends on both, the topology of the neighbouring CS1 and ATPase domain regions and the functionality of the ecto-ATPase activity in addition.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Adhesión Bacteriana , Proteínas Bacterianas/metabolismo , Proteínas Portadoras/metabolismo , Lipoproteínas/metabolismo , Infecciones por Mycoplasma/microbiología , Mycoplasma hominis/fisiología , Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Portadoras/química , Proteínas Portadoras/genética , Células HeLa , Humanos , Lipoproteínas/química , Lipoproteínas/genética , Mycoplasma hominis/química , Mycoplasma hominis/enzimología , Mycoplasma hominis/genética , Estructura Terciaria de Proteína
20.
Access Microbiol ; 3(12): 000285, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35024550

RESUMEN

Rare invasive fungal infections are increasingly emerging in hosts with predisposing factors such as immunodeficiency. Their timely diagnosis remains difficult, as their clinical picture may initially mimic infections with more common fungal species and species identification may be difficult with routine methods or may require time-consuming subcultures. This often results in ineffective drug administration and fatal outcomes. We report on a patient in their early twenties with mixed cellularity classical Hodgkin lymphoma with a disseminated Trichosporon asahii (T. asahii) infection. Even though pathogen detection and identification was possible via the standard procedure consisting of culture followed by matrix-assisted laser desorption ionisation-time of flight (MALDI-TOF) mass spectrometry, the patient passed away in the course of multi organ failure. Herein, we report on a retrospectively applied experimental diagnostic fungal PCR-analysis used on an EDTA blood sample and consisting of two pan-fungal reactions and seven branch-specific reactions. Regarding invasive T. asahii infection, this PCR array could considerably shorten time to diagnosis and switch to a targeted therapy with triazoles.

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