Publications by authors named "Rosch J"

: Acute otitis media (AOM) is a common pediatric infection worldwide and is the primary basis for pediatric primary care visits and antibiotic prescriptions in children. Current licensed vaccines have been incompletely ineffective at reducing the global burden of AOM, underscoring a major unmet medical need. The complex etiology of AOM presents additional challenges for vaccine development, as it can stem from multiple bacterial species including , , and .

View Article and Find Full Text PDF

Bacterial cells secrete extracellular vesicles (EVs), the function of which is a matter of intense investigation. Here, we show that the EVs secreted by the human pathogen (pneumococcus) are associated with bacterial DNA on their surface and can deliver this DNA to the transformation machinery of competent cells. These findings suggest that EVs contribute to gene transfer in Gram-positive bacteria and, in doing so, may promote the spread of drug resistance genes in the population.

View Article and Find Full Text PDF
Article Synopsis
  • Virulence studies on the one-carbon metabolism pathway and proline synthesis indicate their importance in the infection process, particularly in Δ and Δ mutant strains of capsular serotype 6B BHN418.* -
  • These mutant strains showed significantly reduced virulence in models of mouse sepsis and pneumonia despite being able to colonize the nasopharynx and grow normally in nutrient-rich environments.* -
  • Differences in metabolic profiles and gene transcription under various stress conditions revealed strain-specific effects on virulence and metabolism, underscoring the need for rapid adaptation to host physiological conditions.*
View Article and Find Full Text PDF
Article Synopsis
  • Scientists found that a bacteria called Streptococcus pneumoniae uses different systems to talk to itself!
  • Two important parts of the bacteria, PptAB and Eep, help connect these communication systems and control how they work together when the bacteria infect a host!
  • This discovery shows that many types of bacteria could use a similar way to communicate, making it an important finding for understanding germs!
View Article and Find Full Text PDF

Purpose: Traffic accidents persist as a leading cause of death. European law mandates the integration of automatic emergency call systems (eCall). Our project focuses on an automated injury prediction device for car accidents, correlating technical and epidemiological input data, such as age, gender, seating position, impact on the passenger compartment, seatbelt usage, impact direction, EES, vehicle class, and airbag deployment.

View Article and Find Full Text PDF

Commensal gut bacteria use oleate hydratase to release a spectrum of hydroxylated fatty acids using host-derived unsaturated fatty acids. These compounds are thought to attenuate the immune response, but the underlying signaling mechanism(s) remain to be established. The pathogen also expresses an oleate hydratase and 10-hydroxyoctadecanoic acid (18:0) is the most abundant oleate hydratase metabolite found at Staphylococcal skin infection sites.

View Article and Find Full Text PDF

The high potential of siRNAs to silence oncogenic drivers remains largely untapped due to the challenges of tumor cell delivery. Here, divalent lipid-conjugated siRNAs are optimized for in situ binding to albumin to improve pharmacokinetics and tumor delivery. Systematic variation of the siRNA conjugate structure reveals that the location of the linker branching site dictates tendency toward albumin association versus self-assembly, while the lipid hydrophobicity and reversibility of albumin binding also contribute to siRNA intracellular delivery.

View Article and Find Full Text PDF
Article Synopsis
  • Antibiotic resistance is a big problem for global health, and fluoroquinolone resistance is rare even though the drug is often used.
  • * Research found that some bacteria can adapt to survive antibiotics by changing how they use energy, without actually becoming resistant.
  • * This study helps us understand why fluoroquinolone resistance is uncommon, showing that it comes with some disadvantages for bacteria during infections.
View Article and Find Full Text PDF
Article Synopsis
  • Bacterial cells secrete extracellular vesicles (EVs) that are being actively studied for their functions.
  • The study reveals that EVs from the human pathogen pneumococcus carry bacterial DNA on their surface and can transfer this DNA to other bacterial cells capable of taking it up.
  • This process may enhance gene transfer among Gram-positive bacteria, potentially facilitating the spread of drug resistance genes.
View Article and Find Full Text PDF

MISTRG is an immunodeficient mouse strain that expresses multiple human cytokines that support hematopoietic stem cell maintenance and myelopoiesis. While establishing a breeding colony of MISTRG mice in a dedicated barrier room, 6 cases of death or disease occurred in pregnant or postpartum mice. Clinically, this manifested as hunched posture, dyspnea, and 1 case of emaciation with ataxia.

View Article and Find Full Text PDF

Streptococcus pneumoniae is a remarkably adaptable and successful human pathogen, playing dual roles of both asymptomatic carriage in the nasopharynx and invasive disease including pneumonia, bacteremia, and meningitis. Efficacious vaccines and effective antibiotic therapies are critical to mitigating morbidity and mortality. However, clinical interventions can be rapidly circumvented by the pneumococcus by its inherent proclivity for genetic exchange.

View Article and Find Full Text PDF

Glucose, a primary fuel source under homeostatic conditions, is transported into cells by membrane transporters such as glucose transporter 1 (GLUT1). Due to its essential role in maintaining energy homeostasis, dysregulation of GLUT1 expression and function can adversely affect many physiological processes in the body. This has implications in a wide range of disorders such as Alzheimer's disease (AD) and several types of cancers.

View Article and Find Full Text PDF

Objective: Functional magnetic resonance imaging (fMRI) visualizes brain structures at increasingly higher resolution and better signal-to-noise ratio (SNR) as field strength increases. Yet, mapping the blood oxygen level dependent (BOLD) response to distinct neuronal processes continues to be challenging. Here, we investigated the characteristics of 7 T-fMRI compared to 3 T-fMRI in the human brain beyond the effect of increased SNR and verified the benefits of 7 T-fMRI in the detection of tiny, highly specific modulations of functional connectivity in the resting state following a motor task.

View Article and Find Full Text PDF
Article Synopsis
  • Streptococcus pneumoniae is an opportunistic pathogen that can cause serious diseases following asymptomatic colonization in the upper respiratory tract, with inflammation and neutrophil recruitment serving as key defenses.
  • The study focuses on how serine proteases from neutrophils can degrade a signaling peptide called CSP, which is crucial for the bacterium's natural competence—the ability to gain genetic material and adapt.
  • Results show that when CSP is degraded by serine proteases, it significantly reduces the pneumococcus's competence and genetic exchange, highlighting a new way the host immune response can influence bacterial behavior.
View Article and Find Full Text PDF

Fluorescent RNA-based biosensors are useful tools for real-time detection of molecules in living cells. These biosensors typically consist of a chromophore-binding aptamer and a target-binding aptamer, whereby the chromophore-binding aptamer is destabilized until a target is captured, which causes a conformational change to permit chromophore binding and an increase in fluorescence. The target-binding region is typically fabricated using known riboswitch motifs, which are already known to have target specificity and undergo structural changes upon binding.

View Article and Find Full Text PDF

The separation of pneumococcal serotypes from a complex polymicrobial mixture may be required for different applications. For instance, a minority strain could be present at a low frequency in a clinical sample, making it difficult to identify and isolate by traditional culture-based methods. We therefore developed an assay to separate mixed pneumococcal samples using serotype-specific antiserum and a magnetic bead-based separation method.

View Article and Find Full Text PDF

The high potential for therapeutic application of siRNAs to silence traditionally undruggable oncogenic drivers remains largely untapped due to the challenges of tumor cell delivery. Here, siRNAs were optimized for binding to albumin through C lipid modifications to improve pharmacokinetics and tumor delivery. Systematic variation of siRNA conjugates revealed a lead structure with divalent C lipids each linked through three repeats of hexaethylene glycol connected by phosphorothioate bonds.

View Article and Find Full Text PDF

Objective: MRI-negative drug-resistant epilepsy presents a challenge when it comes to surgical planning, and surgical outcome is worse than in cases with an identified lesion. Although increasing implementation of more powerful MRI scanners and artificial intelligence has led to the detection of previously unrecognizable lesions, in some cases even postoperative pathological evaluation of electrographically epileptogenic zones shows no structural alterations. While in temporal lobe epilepsy a standardized resection approach can usually be performed, the surgical management of extra-temporal lesions is always individual.

View Article and Find Full Text PDF

Maintenance of intracellular metal homeostasis during interaction with host niches is critical to the success of bacterial pathogens. To prevent infection, the mammalian innate immune response employs metal-withholding and metal-intoxication mechanisms to limit bacterial propagation. The first-row transition metal ion copper serves critical roles at the host-pathogen interface and has been associated with antimicrobial activity since antiquity.

View Article and Find Full Text PDF

Streptococcus pneumoniae colonizes the human nasopharynx and causes several diseases. Pneumococcal vaccines target the polysaccharide capsule and prevent most serious disease, but there has been an increase in the prevalence of nonencapsulated S. pneumoniae (NESp).

View Article and Find Full Text PDF

Background: For almost a century, it has been recognized that influenza A virus (IAV) infection can promote the development of secondary bacterial infections (SBI) mainly caused by Streptococcus pneumoniae (Spn). Recent observations have shown that IAV is able to directly bind to the surface of Spn. To gain a foundational understanding of how direct IAV-Spn interaction alters bacterial biological fitness we employed combinatorial multiomic and molecular approaches.

View Article and Find Full Text PDF

As opposed to de novo mutation, β-lactam resistance in S. pneumoniae is often conferred via homologous recombination during horizontal gene transfer. We hypothesize that β-lactam resistance in pathogenic streptococci is restricted to naturally competent species via intra-/interspecies recombination due to in vivo fitness trade-offs of de novo penicillin-binding protein (PBP) mutations.

View Article and Find Full Text PDF

Many bacterial species are represented by a pan-genome, whose genetic repertoire far outstrips that of any single bacterial genome. Here we investigate how a bacterial pan-genome might influence gene essentiality and whether essential genes that are initially critical for the survival of an organism can evolve to become non-essential. By using Transposon insertion sequencing (Tn-seq), whole-genome sequencing and RNA-seq on a set of 36 clinical Streptococcus pneumoniae strains representative of >68% of the species' pan-genome, we identify a species-wide 'essentialome' that can be subdivided into universal, core strain-specific and accessory essential genes.

View Article and Find Full Text PDF

Objectives: Intracranial aneurysm (IA) is the main cause of subarachnoid hemorrhages. Time-of-flight (TOF) magnetic resonance angiography (MRA) at 1.5 T or 3 T magnetic resonance imaging (MRI) is a well-established method for the diagnosis of IA.

View Article and Find Full Text PDF