Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) remains one of the deadliest infectious diseases globally. Timely diagnosis is a key step in the management of TB patients and in the prevention of further transmission events. Current diagnostic tools are limited in these regards. There is an urgent need for new accurate non-sputum-based diagnostic tools for the detection of symptomatic as well as subclinical TB. In this study, we recruited 52 symptomatic TB patients (sputum Xpert MTB/RIF positive) and 58 household contacts to assess the accuracy of a sequence-specific hybridization assay that detects the presence of Mtb cell-free DNA in urine. Using sputum Xpert MTB/RIF as a reference test, the magnetic bead-capture assay could discriminate active TB from healthy household contacts with an overall sensitivity of 72.1% [confidence interval (CI) 0.59-0.86] and specificity of 95.5% (CI 0.90-1.02) with a positive predictive value of 93.9% and negative predictive value of 78.2%. The detection of Mtb-specific DNA in urine suggested four asymptomatic TB infection cases that were confirmed in all instances either by concomitant Xpert MTB/RIF sputum testing or by follow-up investigation raising the specificity of the index test to 100%. We conclude that sequence-specific hybridization assays on urine specimens hold promise as non-invasive tests for the detection of subclinical TB.
OBJECTIVE: There is an urgent need for a non-sputum-based diagnostic tool allowing sensitive and specific detection of all forms of tuberculosis (TB) infections. In that context, we performed a case-control study to assess the accuracy of a molecular detection method enabling the identification of cell-free DNA from Mycobacterium tuberculosis that is shed in the urine of tuberculosis patients. We present accuracy data that would fulfill the target product profile for a non-sputum test. In addition, recent epidemiological data suggested that up to 50% of individuals secreting live bacilli do not present with symptoms at the time of screening. We report, here, that the investigated index test could also detect instances of asymptomatic TB infections among household contacts.

Hippoboscid flies are bloodsucking arthropods that can transmit pathogenic microorganisms and are therefore potential vectors for pathogens such as Bartonella spp. These Gram-negative bacteria can cause mild-to-severe clinical signs in humans and animals; therefore, monitoring Bartonella spp. prevalence in louse fly populations appears to be a useful prerequisite for zoonotic risk assessment.
Using convenience sampling, we collected 103 adult louse flies from four ked species (Lipoptena cervi, n = 22; Lipoptena fortisetosa, n = 61; Melophagus ovinus, n = 12; Hippobosca equina, n = 8) and the pupae of M. ovinus (n = 10) in the federal state of Saxony, Germany. All the samples were screened by polymerase chain reaction (PCR) for Bartonella spp. DNA, targeting the citrate synthase gene (gltA). Subsequently, PCRs targeting five more genes (16S, ftsZ, nuoG, ribC and rpoB) were performed for representatives of revealed gltA genotypes, and all the PCR products were sequenced to identify the Bartonella (sub)species accurately.
The overall detection rates for Bartonella spp. were 100.0%, 59.1%, 24.6% and 75.0% in M. ovinus, L. cervi, L. fortisetosa and H. equina, respectively. All the identified bartonellae belong to the Bartonella schoenbuchensis complex. Our data support the proposed reclassification of the (sub)species status of this group, and thus we conclude that several genotypes of B. schoenbuchensis were detected, including Bartonella schoenbuchensis subsp. melophagi and Bartonella schoenbuchensis subsp. schoenbuchensis, both of which have previously validated zoonotic potential. The extensive PCR analysis revealed the necessity of multiple PCR approach for proper identification of the ruminant-associated bartonellae.

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Little is known about the association between bacterial DNA in human blood and the risk of cardiovascular disease (CVD) mortality.
A case-cohort study was performed based on a 9 ½ year follow-up of the Oslo II study from 2000. Eligible for this analysis were men born in 1923 and from 1926 to 1932. The cases were men (n = 227) who had died from CVD, and the controls were randomly selected participants from the same cohort (n = 178). Analysis of the bacterial microbiome was performed on stored frozen blood samples for both cases and controls. Association analyses for CVD mortality were performed by Cox proportional hazard regression adapted to the case-cohort design. We used the Bonferroni correction due to the many bacterial genera that were identified.
Bacterial DNA was identified in 372 (82%) of the blood samples and included 78 bacterial genera from six phyla. Three genera were significantly associated with CVD mortality. The genera Kocuria (adjusted hazard ratio (HR) 8.50, 95% confidence interval (CI) (4.05, 17.84)) and Enhydrobacter (HR 3.30 (2.01, 5.57)) indicate an association with CVD mortality with increasing levels. The genera Paracoccus (HR 0.29 (0.15, 0.57)) was inversely related. Significant predictors of CVD mortality were: the feeling of bad health; and the consumption of more than three cups of coffee per day. The following registered factors were borderline significant, namely: a history of heart failure; increased systolic blood pressure; and currently taking antihypertensive drugs now, versus previously.
The increasing levels of two bacterial genera Kocuria (skin and oral) and Enhydrobacter (skin) and low levels of Paracoccus (soil) were associated with CVD mortality independent of known risk factors for CVD.

Oral microbiome sequencing efforts revealed the presence of hundreds of different microbes. Interindividual differences at strain and species resolution suggest that microbiome diversity could lead to mechanistically distinct gene regulation as well as species-related differences in phenotypes. Commonly, gene regulation and related phenotypes are studied in a few selected strains of a particular species with conclusions that are mostly generalized. The aim of this study was to isolate several species of Corynebacterium using an established protocol that led to the previous isolation of C. durum. Characterization of C. durum interspecies interactions revealed a specific mechanism for chain elongation in Streptococcus sanguinis that was the result of corynebacterial fatty acid production and secretion. While the protocol was successfully applied to isolate what we presumed to be additional Corynebacterium based on several phenotypic traits that seem to be identical to C. durum, genome sequencing of the newly isolated strains placed them closer to Actinomyces. Both Corynebacterium and Actinomyces are suborders of the Actinobacteridae and related species. Our study suggests to take several comprehensive strategies into consideration when taxonomically identifying closely related microorganisms. Furthermore, it seems to be important to test common core phenotypes in bacterial ecology to understand the behavior of specific groups of microbes, rather than simply relying upon genome sequence homology to establish relationships in the microbiome.

Despite the worldwide use of 16S rRNA to identify bacterial species, the use of this gene does not discriminate the 750 species in the genus Streptomyces. A MLST scheme was constructed with rpoB, gyrB, recA, trpB and atpD genes to access the genomic variances in Streptomyces species evolution. We analyze the housekeeping genes in 49 Streptomyces isolates from Antarctic soil. It was used two different databases, GenBank and EzBioCloud to compare the 16S sequences. The species founded in both databases are not the same, but in both cases, a few isolates achieve the necessary high percentage to consider the identification. There is a lack of deposited sequences in the other genes, as the data in GenBank proved to be insufficient. Isolate LMA323St_9 has the potential to be studied as a novel species. Besides that, the use of housekeeping genes gives robust phylogenetic information to understand in group relationships.

The aim of our paper is to present and discuss in detail the bony changes indicative of tuberculosis (TB) that were identified in a skeleton (KB67), unearthed from grave 67 of the 8th-century-CE cemetery of Kaba-Bitózug (Hungary). Furthermore, to provide the differential diagnoses of the observed alterations, with special attention to the cranial osteolytic lesions. During the macro- and micromorphological examinations of KB67, the skull revealed three small, well-circumscribed, punched-out osteolytic lesions accompanied by endocranial granular impressions, abnormal blood vessel impressions, periosteal appositions, and cortical erosion. The postcranial skeleton exhibited osteolytic lesions, cortical remodelling and erosion, and signs of hypervascularisation in the spine. Based on the differential diagnosis of the cranial osteolytic lesions and their co-occurrence with endocranial and vertebral bony changes indicative of TB, they most likely resulted from tuberculous involvement of the frontal and left parietal bones. The morphologically established diagnosis was confirmed by a PCR analysis that provided evidence for the presence of Mycobacterium tuberculosis DNA in KB67. KB67, the first reported archaeological case with calvarial TB from the present-day territory of Hungary, gives us a unique insight into the occurrence of a rare manifestation of TB in the Avar Age of the Great Plain.

Paenibacilli are gram-variable, endospore-forming bacteria that occupy various ecologic niches. These microorganisms have been known to infect humans occasionally at various anatomic sites. However, in humans, as well as in other vertebrate animals, the relationship between disease and isolation of Paenibacillus spp. remains poorly understood. We report here a case of infection in an adult Poodle dog. The animal had nodules in the lungs and multifocal osteolytic expansile bone lesions. From bone, Paenibacillus amylolyticus was recovered by culture and identified by MALDI-TOF mass spectroscopy and 16S rDNA sequencing; pyogranulomatous inflammation was observed in lung and bone specimens. The microorganism was resistant to clindamycin and imipenem. Four-month treatment with amoxicillin-clavulanate resulted in clinical resolution of disease in this dog. Nevertheless, therapy for more prolonged periods should be considered because recurrent infections can occur as a result of the transition of Paenibacillus spores to vegetative cells. Disease caused by a Paenibacillus species has not been reported previously in dogs, to our knowledge.

We present the case of a 72-year-old female patient with acute contained rupture of a biological composite graft, 21 months after replacement of the aortic valve and the ascending aorta due to an aortic dissection. Auramine-rhodamine staining of intraoperative biopsies showed acid-fast bacilli, but classical culture and molecular methods failed to identify any organism. Metagenomic analysis indicated infection with Mycobacterium chelonae, which was confirmed by target-specific qPCR. The complexity of the sample required a customized bioinformatics pipeline, including cleaning steps to remove sequences of human, bovine ad pig origin. Our study underlines the importance of multiple testing to increase the likelihood of pathogen identification in highly complex samples.