Publications by authors named "Sheela Abraham"

The gut microbiome has come to prominence across research disciplines, due to its influence on major biological systems within humans. Recently, a relationship between the gut microbiome and hematopoietic system has been identified and coined the gut-bone marrow axis. It is well established that the hematopoietic system and gut microbiome separately alter with age; however, the relationship between these changes and how these systems influence each other demands investigation.

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  • Extracellular vesicles (EVs) are important carriers of biomolecules, facilitating communication between cells and potentially serving as disease biomarkers, but their analysis can be complicated by methodology.
  • The study outlines a comprehensive method for isolating and analyzing EVs from blood plasma using advanced techniques like surface-enhanced Raman spectroscopy (SERS) and mass spectrometry (MS), focusing on samples from healthy donors and women with early-stage ovarian cancer.
  • By applying machine learning to SERS data, the researchers developed a reliable workflow that could help distinguish between healthy and cancerous EVs, presenting a potential diagnostic tool for early-stage high-grade serous carcinoma.
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  • The study investigates how nutrient starvation, particularly amino acid scarcity, influences mitochondrial dynamics, revealing that cells initiate mitochondrial fusion to avoid degradation.
  • Supplementing with certain amino acids (glutamine, leucine, and arginine) intensifies mitochondrial hyperfusion, driven by specific fusion proteins (Mfn1 and Opa1), but does not involve the MTORC1 pathway.
  • The research highlights the importance of metabolic processes, including the TCA cycle and purine biosynthesis, in the amino acid-induced hyperfusion response, suggesting a mechanism through which cells sense and respond to nutrient availability.
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Extracellular vesicles (EVs) are small lipid bilayer particles containing biologically important cargo and impart regulatory changes in target cells. Despite the importance of EVs in cellular communication, there remains a gap in our understanding of how EVs influence HSC fate and, in turn, how aging and longevity are affected. This review summarizes the current literature dealing with how age-altered intercellular communication mediated by EVs influences HSC biology.

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Acute myeloid leukemia (AML) is a typically lethal molecularly heterogeneous disease, with few broad-spectrum therapeutic targets. Unusually, most AML retain wild-type TP53, encoding the pro-apoptotic tumor suppressor p53. MDM2 inhibitors (MDM2i), which activate wild-type p53, and BET inhibitors (BETi), targeting the BET-family co-activator BRD4, both show encouraging pre-clinical activity, but limited clinical activity as single agents.

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Background: There is limited data on the prevalence of Candida species in infected root canal systems of human teeth. We attempted to investigate the prevalence, genotype, virulence and the antifungal susceptibility of Candida albicans isolated from infected root canals of patients with primary and post-treatment infections in a UAE population.

Methods: Microbiological samples from 71 subjects with infected root canals were aseptically collected, and cultured on Sabouraud dextrose agar, and C.

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Hematopoietic stem cells (HSCs) maintain balanced blood cell production in a process called hematopoiesis. As humans age, their HSCs acquire mutations that allow some HSCs to disproportionately contribute to normal blood production. This process, known as age-related clonal hematopoiesis, predisposes certain individuals to cancer, cardiovascular and pulmonary pathologies.

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Background: Dentine hypersensitivity is a frequent oral complaint that is usually associated with several factors including diet and oral hygiene practices.

Objective: The aim of this study was to assess the prevalence, severity and correlates of dentine hypersensitivity and dentine exposure-related risk indicators in a sample from six Arab countries.

Methods: A multinational cross-sectional study was conducted on a sample of 2924 participants, attending dental practices, aged 18-35 years from six Arab countries.

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Background: To analyze the impact of the International Nosocomial Infection Control Consortium (INICC) Multidimensional Approach (IMA) and use of INICC Surveillance Online System (ISOS) on ventilator-associated pneumonia (VAP) rates in Saudi Arabia from September 2013 to February 2017.

Methods: A multicenter, prospective, before-after surveillance study on 14,961 patients in 37 intensive care units (ICUs) of 22 hospitals. During baseline, we performed outcome surveillance of VAP applying the definitions of the CDC/NHSN.

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Objective: An important determinant of job satisfaction and life fulfillment is the quality of life (QOL) of the individuals working in a particular field. Currently, in the United Arab Emirates (UAE), there is limited research pertaining to the QOL of dentists. The main objective of this study was to assess QOL of dentists in the UAE.

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Chronic myeloid leukemia (CML) stem/progenitor cells (SPCs) express a transcriptional program characteristic of proliferation, yet can achieve and maintain quiescence. Understanding the mechanisms by which leukemic SPCs maintain quiescence will help to clarify how they persist during long-term targeted treatment. We have identified a novel BCR-ABL1 protein kinase-dependent pathway mediated by the upregulation of , the downregulation of its direct target early growth response 1 (EGR1), and, as a consequence, upregulation of E2F1.

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. To investigate the cavity adaptation of mineral trioxide (ProRoot MTA/MT), tricalcium silicate (Biodentine/BD), and glass ionomer (Equia Fil/EF) cements used as liners and the interfacial integrity between those liners and a composite resin placed as the main restorative material. .

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Xenograft mouse models have been instrumental in expanding our knowledge of hematopoiesis and can provide a functional description of stem cells that possess engrafting potential. Here we describe methodology outlining one way of analyzing human malignant cells that are able to engraft immune compromised mice. Using models such as these will allow researchers to gain valuable insight into the primitive leukemic subtypes that evade current therapy regimes and are critical to understand, in order to eradicate malignancy.

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Chronic myeloid leukaemia (CML) arises after transformation of a haemopoietic stem cell (HSC) by the protein-tyrosine kinase BCR-ABL. Direct inhibition of BCR-ABL kinase has revolutionized disease management, but fails to eradicate leukaemic stem cells (LSCs), which maintain CML. LSCs are independent of BCR-ABL for survival, providing a rationale for identifying and targeting kinase-independent pathways.

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The regulation of hematopoietic stem cell (HSC) survival and self-renewal within the bone marrow (BM) niche is not well understood. We therefore investigated global transcriptomic profiling of normal human HSC/hematopoietic progenitor cells [HPCs], revealing that several chemokine ligands (CXCL1-4, CXCL6, CXCL10, CXCL11, and CXCL13) were upregulated in human quiescent CD34(+)Hoescht(-)Pyronin Y(-) and primitive CD34(+)38(-), as compared with proliferating CD34(+)Hoechst(+)Pyronin Y(+) and CD34(+)38(+) stem/progenitor cells. This suggested that chemokines might play an important role in the homeostasis of HSCs.

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Objective: The purpose of this study was to determine the root canal anatomy of mandibular first premolar teeth in an Emirati subpopulation using a decalcification and clearing method.

Materials And Methods: One hundred permanent mandibular first premolar teeth extracted for orthodontic purposes from an Emirati subpopulation from the United Arab Emirates were used for this study. They were subjected to decalcification and clearing.

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Cancer stem cells (CSCs) are responsible for the initiation and maintenance of some types of cancer, suggesting that inhibition of these cells may limit disease progression and relapse. Unfortunately, few CSC-specific genes have been identified. Here, we determined that the gene encoding arachidonate 15-lipoxygenase (Alox15/15-LO) is essential for the survival of leukemia stem cells (LSCs) in a murine model of BCR-ABL-induced chronic myeloid leukemia (CML).

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Objective: The purpose of this study was to investigate compliance, awareness and practices of infection control procedures among senior dental students at the College of Dentistry, University of Sharjah, United Arab Emirates.

Materials And Methods: The study comprised of 119 subjects of 4(th) and 5(th) year dental students. A questionnaire was developed with 25 open and closed-ended questions related to barrier techniques, vaccination status, infection control practices and awareness.

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In this issue of Blood, Walker et al investigate the preclinical potential of KPT-330, an exportin-1 (XPO1, also known as chromosome maintenance protein 1 [CRM1]) inhibitor, against both accelerated phase (AP) and blast crisis chronic myeloid leukemia (CML-BC) and against Philadelphia chromosome-positive (Ph1) acute lymphoblastic leukemia (ALL), all of which are diseases of significant unmet clinical need.1 The authors provide encouraging data from both a leukemic mouse model and a single CML-AP patient, corroborating mechanistic studies suggesting that KPT-330 efficacy relies on targeting abundantly expressed XPO1, followed by the reactivation of protein phosphatase 2A (PP2A).

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CXCL12 governs cellular motility, a process deregulated by hematopoietic stem cell oncogenes such as p210-BCR-ABL. A phosphoproteomics approach to the analysis of a hematopoietic progenitor cell line treated with CXCL12 and the Rac 1 and 2 inhibitor NSC23766 has been employed to objectively discover novel mechanisms for regulation of stem cells in normal and malignant hematopoiesis. The proteomic data sets identified new aspects of CXCL12-mediated signaling and novel features of stem cell regulation.

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Chronic myeloid leukaemia (CML) arises in a haemopoietic stem cell and is driven by the Bcr-Abl oncoprotein. Abl kinase inhibitors (protein tyrosine kinase inhibitors) represent standard treatment for CML and induce remission in the majority of patients with early disease, however these drugs do not target leukaemic stem cells (LSCs) effectively, thus preventing cure. Previously, we identified the farnesyl transferase inhibitor BMS-214662 as a selective inducer of apoptosis in LSCs of CML patients relative to normal controls; however, the mechanism underlying LSC-specific apoptosis remains unclear.

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Chronic myeloid leukemia (CML) is the first cancer in which a genetic alteration was proven to be of pathogenic significance and is considered a disease model for oncogene addiction, targeted therapy, and cancer stem cells (CSCs). The introduction of tyrosine kinase inhibitors (TKIs) resulted in dramatic improvement in response and survival for patients with CML in chronic phase (CP); however, CSCs are spared by TKIs. In this article, we review the role of CSCs in CML in CP, their persistence following TKI treatment, and current approaches to target this population in an attempt to achieve disease cure.

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Effective cancer chemotherapy depends on the delivery of therapeutic drugs to cancer cells at cytotoxic concentrations. However, physiologic barriers, such as variable vessel permeability, high interstitial fluid pressure, and heterogeneous perfusion, make it difficult to achieve that goal. Efforts to improve drug delivery have been limited by the lack of noninvasive tools to evaluate intratumoral drug concentration and distribution.

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