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Karaaslan BG, Rosain J, Bustamante J, Kiykim A
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Interferon Gamma in Sickness Predisposing to Mycobacterial Infectious ...

BALKAN MEDICAL JOURNAL 2024 SEP; 41(5):326-332
In recent decades, the prevalence of inborn errors of immunity has increased, necessitating the development of more effective treatment and care options for these highly morbid conditions. Due to these "experiments of nature," the complicated nature of the immune system is being revealed. Based on the functional and molecular tests, targeted therapies are now being developed which offer a more effective approach and reduce damage. This study aimed to investigate a key cytokine of the cellular immune response, interferon-gamma (IFN-gamma), gamma ), which is linked to Mendelian susceptibility to Mycobacterial disease, and its potential as a therapeutic option for IFN-gamma gamma deficiency.
Lopes J, de Lencastre H, Conceiçao T
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Genomic analysis of Enterococcus faecium from non-clinical settings: a...

FRONTIERS IN MICROBIOLOGY 2024 SEP 11; 15(?):? Article 1466990
Introduction Enterococci are commensals of the gastrointestinal tract of humans and animals that evolved into opportunistic pathogens with high antimicrobial resistance and virulence. Multidrug-resistant Enterococcus is a major cause of hospital-acquired infections worldwide. For this reason, the characterization of non-clinical reservoirs of Enterococci and their epidemiological link to resistant hospital isolates is crucial for controlling their spread. Methods A total of 295 samples collected from livestock (pigs and cows, n = 135) and environment (public buses, passengers hands, and urban environments, n = 160) were screened for Enterococcus spp. E. faecium antimicrobial resistance profiles, virulence potential, and clonal population were further characterized. Results Enterococci were detected in 90.5% (n = 267) of the samples, with a higher prevalence in livestock (100%) than the environment (82.5%, p < 0.0001), but none of the isolates exhibited vancomycin resistance. E. faecalis was the most prevalent species (51.7%), predominantly found in livestock (62.2%), while E. faecium was more common in the environment. Of the 59 E. faecium isolates, 78% showed resistance to >= 3 antibiotic classes and contained associated resistance genes, namely tetracyclines (tetM and tetL), beta-lactams (mutations in pbp5), and high-level resistance to aminoglycosides (ant(6)-Ia and aac(6 ')-aph(2 '')). A wide array of virulence factors was detected among E. faecium, associated with adherence, biofilm formation, and adaptation to host response, while hospital-associated virulence markers, such as IS16, were less frequent, probably due to the non-clinical nature of the isolates. Clonal population analysis revealed a diverse E. faecium population. Although no direct epidemiological link could be traced between our isolates and specific clinical isolates, infection-associated genetic backgrounds were identified in non-clinical isolates: one isolate from pigs belonged to CC17 (ST32), while four isolates belonged to CC94, including one recovered from pigs (ST296), one from cows (ST2206), one from the urban environment (ST1205), and other from buses (ST800). Discussion This study underscores a high prevalence of clinically relevant Enterococcus species among healthy livestock and the environment. Despite the absence of vancomycin resistance and limited hospital infection-associated clonal lineages, the presence of E. faecium with significant virulence potential and resistance to critical antibiotics in human and veterinary medicine highlights the need for continuing surveillance of non-clinical reservoirs.
Candeias C, Almeida ST, Paulo AC, Simoes AS, Ferreira B, Cruz AR, Queirós M, ...
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Streptococcus pneumoniae carriage, serotypes, genotypes, and antimicrobial re...

VACCINE 2024 SEP 17; 42(22):? Article 126219
Streptococcus pneumoniae carriage studies are crucial to monitor changes induced by use of pneumococcal conjugate vaccines and inform vaccination policies. In this cross-sectional study, we examined changes within the pneumococcal population following introduction of PCV13 in 2015 in the National Immunization Program (NIP), in Portugal. In 2018-2020 (NIP-PCV13), we obtained 1450 nasopharyngeal samples from children <= 6 years attending day-care. We assessed serotypes, antimicrobial resistance, and genotypes (MLST and GPSC) and compared findings with earlier periods: 2009-2010 (pre-PCV13), 2011-2012 (early-PCV13), and 2015-2016 (late-PCV13). Pneumococcal carriage prevalence remained stable at 60.2 %. Carriage of PCV13 serotypes was 10.7 %, markedly reduced compared to pre-PCV13 period (47.6 %). The most prevalent PCV13 serotypes were 19F, 3, and 19A all showing a significant decreasing trend compared to the pre-PCV13 period (from 7.1 % to 4.7 %, 10.1 % to 1.8 %, and 14.1 % to 1.8 %, respectively), a notable observation given the described limited effectiveness of PCV13 against serotype 3. Non-vaccinated children and children aged 4-6 years were more likely to carry PCV13 serotypes (2.5-fold, 95 %CI [1.1-5.6], and 2.9-fold, 95 %CI [1.3-6.8], respectively). The most prevalent non-PCV13 serotypes were 15B/C, 11A, 23B, 23A, and NT, collectively accounting for 51.9 % of all isolates. In total, 30.5 % of all pneumococci were potentially covered by PCV20. Resistance to penicillin (lowlevel) and macrolides increased significantly, from 9.3 % and 13.4 %, respectively, in the late-PCV13 period, to approximately 20 % each, mostly due to lineages expressing non-PCV13 serotypes, nearing pre-PCV13 levels. An expansion of lineages traditionally associated with PCV13 serotypes, like CC156-GPSC6 (serotype 14) and CC193-GPSC11 (serotype 19F), but now predominantly expressing non-PCV13 serotypes (11A, 15B/C, and 24F for GPSC6; and 15A and 21 for GPSC11) was noted. These findings indicate that the pneumococcal population is adapting to the pressures conferred by PCV13 and antimicrobial use and indicate the need to maintain close surveillance.
Mc Larney BE, Sonay AY, Apfelbaum E, Mostafa N, Monette S, Goerzen D, Aguirre...
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A pan-cancer dye for solid-tumour screening, resection and wound monitoring v...

NATURE BIOMEDICAL ENGINEERING 2024 SEP; 8(9):?
The efficacy of fluorescence-guided surgery in facilitating the real-time delineation of tumours depends on the optical contrast of tumour tissue over healthy tissue. Here we show that CJ215-a commercially available, renally cleared carbocyanine dye sensitive to apoptosis, and with an absorption and emission spectra suitable for near-infrared fluorescence imaging (wavelengths of 650-900 nm) and shortwave infrared (SWIR) fluorescence imaging (900-1,700 nm)-can facilitate fluorescence-guided tumour screening, tumour resection and the assessment of wound healing. In tumour models of either murine or human-derived breast, prostate and colon cancers and of fibrosarcoma, and in a model of intraperitoneal carcinomatosis, imaging of CJ215 with ambient light allowed for the delineation of nearly all tumours within 24 h after intravenous injection of the dye, which was minimally taken up by healthy organs. At later timepoints, CJ215 provided tumour-to-muscle contrast ratios up to 100 and tumour-to-liver contrast ratios up to 18. SWIR fluorescence imaging with the dye also allowed for quantifiable non-contact wound monitoring through commercial bandages. CJ215 may be compatible with existing and emerging clinical solutions. A commercial near-infrared dye that is sensitive to apoptosis and that provides high tumour-to-muscle and tumour-to-liver contrast ratios facilitates fluorescence-guided tumour screening, tumour resection and the assessment of wound healing.
Gervais A, Marchal A, Fortova A, Berankova M, Krbkova L, Pychova M, Salat J, ...
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Autoantibodies neutralizing type I IFNs underlie severe tick-borne encephalit...

JOURNAL OF EXPERIMENTAL MEDICINE 2024 SEP 24; 221(10):? Article e20240637
Tick-borne encephalitis (TBE) virus (TBEV) is transmitted to humans via tick bites. Infection is benign in >90% of the cases but can cause mild (<5%), moderate (<4%), or severe (<1%) encephalitis. We show here that similar to 10% of patients hospitalized for severe TBE in cohorts from Austria, Czech Republic, and France carry auto-Abs neutralizing IFN-alpha 2, -beta, and/or -omega at the onset of disease, contrasting with only similar to 1% of patients with moderate and mild TBE. These auto-Abs were found in two of eight patients who died and none of 13 with silent infection. The odds ratios (OR) for severe TBE in individuals with these auto-Abs relative to those without them in the general population were 4.9 (95% CI: 1.5-15.9, P < 0.0001) for the neutralization of only 100 pg/ml IFN-alpha 2 and/or -omega, and 20.8 (95% CI: 4.5-97.4, P < 0.0001) for the neutralization of 10 ng/ml IFN-alpha 2 and -omega. Auto-Abs neutralizing type I IFNs accounted for similar to 10% of severe TBE cases in these three European cohorts.
Huber T, Horioka-Duplix M, Chen YH, Saca VR, Ceraudo E, Chen Y, Sakmar TP
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The role of signaling pathways mediated by the GPCRs CysLTR1/2 in melanocyte ...

SCIENCE SIGNALING 2024 SEP 17; 17(854):? Article eadp3967
In contrast with sun exposure-induced melanoma, rarer melanocytic tumors and neoplasms with low mutational burden present opportunities to study isolated signaling mechanisms. These include uveal melanoma and blue nevi, which are often driven by mutations within the G protein-coupled signaling cascade downstream of cysteinyl leukotriene receptor 2. Here, we review how the same mutations within this pathway drive the growth of melanocytes in one tissue but can inhibit the growth of those in another, exemplifying the role of the tissue environment in the delicate balance between uncontrolled cell growth and senescence.
Singh D, Soni N, Hutchings J, Echeverria I, Shaikh F, Duquette M, Suslov S, L...
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The molecular architecture of the nuclear basket

CELL 2024 SEP 19; 187(19):?
The nuclear pore complex (NPC) is the sole mediator of nucleocytoplasmic transport. Despite great advances in understanding its conserved core architecture, the peripheral regions can exhibit considerable variation within and between species. One such structure is the cage-like nuclear basket. Despite its crucial roles in mRNA surveillance and chromatin organization, an architectural understanding has remained elusive. Using in-cell cryo-electron tomography and subtomogram analysis, we explored the NPC's structural variations and the nuclear basket across fungi (yeast; S. cerevisiae), mammals (mouse; M. musculus), and protozoa (T. gondii). Using integrative structural modeling, we computed a model of the basket in yeast and mammals that revealed how a hub of nucleoporins (Nups) in the nuclear ring binds to basket-forming Mlp/Tpr proteins: the coiled-coil domains of Mlp/Tpr form the struts of the basket, while their unstructured termini constitute the basket distal densities, which potentially serve as a docking site for mRNA preprocessing before nucleocytoplasmic transport.
Friedman JM
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The discovery and development of GLP-1 based drugs that have revolutionized t...

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2024 SEP 16; 121(39):? Article e2415550121
The 2024 Lasker similar to DeBakey Clinical Medical Research Award has been given to Joel Habener and Svetlana Mojsov for their discovery of a new hormone GLP-1(7-37) and to Lotte Knudsen for her role in developing sustained acting versions of this hormone as a treatment for obesity. Each of the three had a distinct set of skills that made this advance possible; Habener is an endocrinologist and molecular biologist, Mojsov is a peptide chemist, and Knudsen is a pharmaceutical scientist. Their collective efforts have done what few thought possible-the development of highly effective medicines for reducing weight. Their research has also solved a mystery that began more than a century ago.
Krammer T, Stuart HT, Gromberg E, Ishihara K, Cislo D, Melchionda M, Perez FB...
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Mouse neural tube organoids self-organize floorplate through BMP-mediated clu...

DEVELOPMENTAL CELL 2024 AUG 5; 59(15):?
During neural tube (NT) development, the notochord induces an organizer, the floorplate, which secretes Sonic Hedgehog (SHH) to pattern neural progenitors. Conversely, NT organoids (NTOs) from embryonic stem cells (ESCs) spontaneously form floorplates without the notochord, demonstrating that stem cells can self-organize without embryonic inducers. Here, we investigated floorplate self-organization in clonal mouse NTOs. Expression of the floorplate marker FOXA2 was initially spatially scattered before resolving into multiple clusters, which underwent competition and sorting, resulting in a stable "winning"floorplate. We identified that BMP signaling governed long-range cluster competition. FOXA2+ + clusters expressed BMP4, suppressing FOXA2 in receiving cells while simultaneously expressing the BMP-inhibitor NOGGIN, promoting cluster persistence. Noggin mutation perturbed floorplate formation in NTOs and in the NT in vivo at mid/hindbrain regions, demonstrating how the floorplate can form autonomously without the notochord. Identifying the pathways governing organizer self-organization is critical for harnessing the developmental plasticity of stem cells in tissue engineering.
Hanzel M, Fernando K, Maloney SE, Horn Z, Gong SC, Maetlik K, Zhao JJ, Pasoll...
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Mice lacking Astn2 have ASD- like behaviors and altered cerebellar circuit pr...

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2024 AUG 20; 121(34):? Article e2405901121
Astrotactin 2 (ASTN2) is a transmembrane neuronal protein highly expressed in the cerebellum that functions in receptor trafficking and modulates cerebellar Purkinje cell (PC) synaptic activity. Individuals with ASTN2 mutations exhibit neurodevelopmental disorders, including autism spectrum disorder (ASD), attention- deficit/hyperactivity disorder (ADHD), learning difficulties, and language delay. To provide a genetic model for the role of the cerebellum in ASD- related behaviors and study the role of ASTN2 in cerebellar circuit function, we generated global and PC- specific conditional Astn2 knockout (KO and cKO, respectively) mouse lines. Astn2 KO mice exhibit strong ASD- related behavioral phenotypes, including a marked decrease in separation- induced pup ultrasonic vocalization calls, hyperactivity, repetitive behaviors, altered behavior in the three- chamber test, and impaired cerebellar- dependent eyeblink conditioning. Hyperactivity and repetitive behaviors are also prominent in Astn2 cKO animals, but they do not show altered behavior in the three- chamber test. By Golgi staining, Astn2 KO PCs have region- specific changes in dendritic spine density and filopodia numbers. Proteomic analysis of Astn2 KO cerebellum reveals a marked upregulation of ASTN2 family member, ASTN1, a neuron- glial adhesion protein. Immunohistochemistry and electron microscopy demonstrate a significant increase in Bergmann glia volume in the molecular layer of Astn2 KO animals. Electrophysiological experiments indicate a reduced frequency of spontaneous excitatory postsynaptic currents (EPSCs), as well as increased amplitudes of both spontaneous EPSCs and inhibitory postsynaptic currents in the Astn2 KO animals, suggesting that pre- and postsynaptic components of synaptic transmission are altered. Thus, ASTN2 regulates ASD-like behaviors and cerebellar circuit properties.