Publications by authors named "Larbi A"

Background: Immune ageing complicates cancer treatment in older individuals. While immunotherapy targeting the PD-1/PD-L1 pathway can reinvigorate T cells, these cells tend to become senescent with age. This study investigates different CD8 T cell subsets usually associated with senescence, in cancer patients over 70 years old who are undergoing anti-PD-1/PD-L1 immunotherapy, and examines the relationship between these senescent cells and prior chemotherapy exposure.

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Long-term control of viral replication relies on the efficient differentiation of memory T cells into effector T cells during secondary immune responses. Recent findings have identified T cell precursors for both memory and exhausted T cells, suggesting the existence of progenitor-like effector T cells. These cells can persist without antigenic challenge but expand and acquire effector functions upon recall immune responses.

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While rapid demographic changes in Asia are driving the incidence of chronic aging-related diseases, the limited availability of high-quality in vivo data hampers our ability to understand complex multi-factorial contributions, including gut microbial, to healthy aging. Leveraging a well-phenotyped cohort of community-living octogenarians in Singapore, we used deep shotgun-metagenomic sequencing for high-resolution taxonomic and functional characterization of their gut microbiomes (n = 234). Joint species-level analysis with other Asian cohorts identified distinct age-associated shifts characterized by reduction in microbial richness, and specific Alistipes and Bacteroides species enrichment (e.

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Semen cryopreservation results in the differential remodeling of the molecules presented in sperm, and these alterations related to reductions in sperm quality and its physiological function have not been fully understood. Given this, this study aimed to investigate the cryoinjury mechanism of goat sperm by analyzing changes of the metabolic characteristics in sperm during the cryopreservation process. The ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) technique was performed to explore metabolite profiles of fresh sperm (C group), equilibrated sperm (E group), and frozen-thawed sperm (F group).

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The immune system is a highly complex and tightly regulated system that plays a crucial role in protecting the body against external threats, such as pathogens, and internal abnormalities, like cancer cells. It undergoes development during fetal stages and continuously learns from each encounter with pathogens, allowing it to develop immunological memory and provide a wide range of immune protection. Over time, after numerous encounters and years of functioning, the immune system can begin to show signs of erosion, which is commonly named immunosenescence.

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Infection by pathogenic microbes is widely hypothesized to be a risk factor for the development of neurocognitive disorders and dementia, but evidence remains limited. We analyzed the association of seropositivity to 11 common pathogens and cumulative infection burden with neurocognitive disorder (mild cognitive impairment and dementia) in a population-based cohort of 475 older individuals (mean age = 67.6 y) followed up over 3-5 years for the risk of MCI-dementia.

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Insofar as they play an important role in the pathogenesis of colorectal cancer (CRC), this study analyzes the serum profile of cytokines, chemokines, growth factors, and soluble receptors in patients with CRC and cancer-free controls as possible CRC signatures. Serum levels of 65 analytes were measured in patients with CRC and age- and sex-matched cancer-free controls using the ProcartaPlex Human Immune Monitoring 65-Plex Panel. Of the 65 tested analytes, 8 cytokines (CSF-3, IFN-γ, IL-12p70, IL-18, IL-20, MIF, TNF-α and TSLP), 8 chemokines (fractalkine, MIP-1β, BLC, Eotaxin-1, Eotaxin-2, IP-10, MIP-1a, MIP-3a), 2 growth factors (FGF-2, MMP-1), and 4 soluble receptors (APRIL, CD30, TNFRII, and TWEAK), were differentially expressed in CRC.

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Calcium (Ca) is required for the growth and development of sheep, but the requirement of (YSW) rams remains uncovered. The current study aims to estimate the Ca requirement of growing YSW rams based on their growth performance, Ca utilization, and serum biochemical indexes. Forty-five YSW rams (10-month-olds) were randomly allocated to five dietary treatments with varying Ca levels of 0.

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  • Type 1 diabetes (T1DM) is an autoimmune disease that destroys insulin-producing cells in the pancreas, and this study aimed to evaluate immune cell changes at the single-cell level for the first time.
  • Researchers analyzed immune cells from 46 T1DM patients and 31 controls, finding significant gene expression alterations in immune cells that were greater than those observed in another autoimmune disease, systemic lupus erythematosus (SLE).
  • The study developed a new metric, the T1DM metagene z-score (TMZ score), which could categorize patients, correlate with existing immune markers, and help inform treatment responses, highlighting the major immune shifts present in T1DM.
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This comprehensive review critically examines the application of proteomics in understanding sperm cryoinjury mechanisms in livestock animals, in the context of the widespread use of semen cryopreservation for genetic conservation. Despite its global adoption, cryopreservation often detrimentally affects sperm quality and fertility due to cryoinjuries. These injuries primarily arise from ice crystal formation, osmotic shifts, oxidative stress, and the reorganization of membrane proteins and lipids during freezing and thawing, leading to premature capacitation-like changes.

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This study aims to assess the impact of semen collection methods on goat semen quality and seminal plasma (SP) proteomes. Semen was collected by artificial vagina (AV) or electro-ejaculator (EE) and semen parameters were evaluated. Tandem mass tag coupled with liquid chromatography-tandem mass spectrometry was used to screen SP differentially abundant proteins (DAPs) between EE and AV.

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Mechanosensitive molecular junctions, where conductance is sensitive to an applied stress such as force or displacement, are a class of nanoelectromechanical systems unique for their ability to exploit quantum mechanical phenomena. Most studies so far relied on reconfiguration of the molecule-electrode interface to impart mechanosensitivity, but this approach is limited and, generally, poorly reproducible. Alternatively, devices that exploit conformational flexibility of molecular wires have been recently proposed.

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  • - Nicotinamide riboside (NR) boosts blood NAD+ levels, potentially enhancing brain function, which was tested in a pilot study on older adults with mild cognitive impairment (MCI) to assess its safety and effectiveness.
  • - In the study, 20 participants received either NR or a placebo for 10 weeks, showing significant increases in blood NAD+ levels without notable adverse effects; however, cognitive measures like the Montreal Cognitive Assessment (MoCA) remained stable overall.
  • - Results indicated NR reduced cerebral blood flow in specific brain areas but did not significantly improve cognitive performance compared to placebo, while showing some positive trends in DNA methylation and aging markers.
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Background: Inflammatory breast cancer (IBC), accounts for the majority of deaths associated with breast tumors. Because this form is aggressive from its appearance and has a strong metastatic potential. The majority of patients are not diagnosed until late stages, highlighting the need for the development of novel diagnostic biomarkers.

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Introduction: Clinically, Alzheimer's disease (AD) is a syndrome with a spectrum of various cognitive disorders. There is a complete dissociation between the pathology and the clinical presentation. Therefore, we need a disruptive new approach to be able to prevent and treat AD.

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Background: Epithelial ovarian cancer (EOC) is the leading cause of death associated with gynecologic tumors. EOC is asymptomatic in early stages, so most patients are not diagnosed until late stages, highlighting the need to develop new diagnostic biomarkers. Mediators of the tumoral microenvironment may influence EOC progression and resistance to treatment.

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Objectives: Platelets and low-density neutrophils (LDNs) are major players in the immunopathogenesis of SLE. Despite evidence showing the importance of platelet-neutrophil complexes (PNCs) in inflammation, little is known about the relationship between LDNs and platelets in SLE. We sought to characterize the role of LDNs and Toll-like receptor 7 (TLR7) in clinical disease.

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Human ageing is accompanied by poor responses to infection and decreased vaccine efficacy. While the causes of this can be attributed to defects in the immune system that increase with age, it is unknown whether mitochondrial dysfunction may also contribute to these phenomena. This study aims to assess mitochondrial dysfunction in CD4+ terminal effector memory T cells re-expressing CD45RA (TEMRA) cells and other CD4+ memory T cell subtypes, which are increased in number in the elderly population, with respect to how their metabolic responses to stimulation are altered compared to CD4+ naïve T cells.

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Background: The uptake of sickle cell trait (SCT) test is challenged by several factors. A community of healthcare professionals educating the public to undergo screening is critical in reducing the disease burden. We investigated knowledge and attitude towards premarital SCT screening among healthcare trainee students who are the next generation of healthcare practitioners.

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  • - Filarial infections affect over 150 million people in tropical regions, often causing lymphedema, which alters immune responses and could change the behavior of skin bacteria in affected individuals.
  • - A study conducted in Ghana analyzed 160 lymphedema patients by taking samples from their ulcers and skin to test for antibiotic resistance, revealing high resistance rates to multiple antibiotics, including chloramphenicol and tetracycline.
  • - Results showed that a significant portion of bacteria isolated from these patients were methicillin-resistant, indicating that treating infections in lymphedema patients may be challenging due to reduced effectiveness of antibiotics.
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Langerhans cell histiocytosis (LCH) is a potentially fatal neoplasm characterized by the aberrant differentiation of mononuclear phagocytes, driven by mitogen-activated protein kinase (MAPK) pathway activation. LCH cells may trigger destructive pathology yet remain in a precarious state finely balanced between apoptosis and survival, supported by a unique inflammatory milieu. The interactions that maintain this state are not well known and may offer targets for intervention.

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  • This study assessed the effects of four different semen extenders on the quality and fertility of goat semen after thawing, using semen from six Yunshang Black bucks.
  • Results showed that Andromed® and Optidyl® produced better sperm motility, integrity, and lower abnormalities compared to l-α SL and milk extenders.
  • Thawing with Andromed® and Optidyl® resulted in similar pregnancy and lambing rates, while the milk group had significantly lower rates, indicating that soybean lecithin can effectively replace egg yolk in goat semen cryopreservation.
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Background: Sarcopenia is common among older individuals with and without type 2 diabetes mellitus (T2DM). There are conflicting evidence in support of the role of insulin in the development of age-related and T2DM-related sarcopenia. We investigated the relationships between the levels of fasting insulin and other blood biomarkers related to insulin or lipid metabolism with the presence of sarcopenia in two independent studies.

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Biotherapeutics, such as recombinant proteins and monoclonal antibodies, have become mainstays of modern medicine as shown by their increasing number in the WHO Model List of Essential Medicines. However, despite frequently offering clinical advantages over standards of care, they remain largely out of reach for populations in low-income and middle-income countries (LMICs), partly because of high costs. Accordingly, the WHO Model List of Essential Medicines Expert Committee has requested that the Medicines Patent Pool explore intellectual property licensing to address this challenge.

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