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Systemic fusarium infection in cancer patients : a report of two cases

Mohamed, M., Ariffin, H., Arasu, A., Tuck Soon, S.H., Abdullah, W.A., Lin, H.P.

Malaysian Journal of Paediatrics and Child Health, 1998;10(2):55-58.
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Fusarium species is an emerging genus of fungal pathogens which until recently were rare causes of human disease apart from localized infection of the skin and nails. Two cases of fungaemia due to Fusarium sp. in children are described. The first child, an 8-year old girl with acute myeloid leukaemia developed character-sitic pyoderma gangrenosum-like skin lesions before succumbing to disseminated Fusarium infection and acute respiratory distress syndrome. The second child, a 5-month old boy, developed pneumonia associated with a transient erythematous skin rash while on chemother-apy for congenital leukaemia. Both patients had Fusarium isolated from blood. The second child improved after six weeks of treatment with ampho-tericin B and granulocyte-macrophage colony stimulat-ing factor but ultimately she died of the disease follow-ing discharge. Fusarium spp should be recognised as an opportunistic pathogen in immunocompromised patients. Current literature suggests that liposomal amphotericin B in conjunction with leukocyte growth factors are the treatment of choice in this potentially fatal infection.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins
A targeted approach to genome-wide studies reveals new genetic associations with central corneal thickness

Benson MD, Khor CC, Gage PJ, Lehmann OJ

Mol Vis, 2017;23:952-962.
PMID: 29296075

Purpose: To evaluate the ability of a targeted genome-wide association study (GWAS) to identify genes associated with central corneal thickness (CCT).
Methods: A targeted GWAS was used to investigate whether ten candidate genes with known roles in corneal development were associated with CCT in two Singaporean populations. The single nucleotide polymorphisms (SNPs) within a 500 kb interval encompassing each candidate were analyzed, and in light of the resulting data, members of the Wnt pathway were subsequently screened using similar methodology.
Results: Variants within the 500 kb interval encompassing three candidate genes, DKK1 (rs1896368, p=1.32×10-3), DKK2 (rs17510449, p=7.34×10-4), and FOXO1 (rs7326616, p=1.56×10-4 and rs4943785, p=1.19×10-3), were statistically significantly associated with CCT in the Singapore Indian population. DKK2 was statistically significantly associated with CCT in a separate Singapore Malaysian population (rs10015200, p=2.26×10-3). Analysis of Wnt signaling pathway genes in each population demonstrated that TCF7L2 (rs3814573, p=1.18×10-3), RYK (rs6763231, p=1.12×10-3 and rs4854785, p=1.11×10-3), and FZD8 (rs640827, p=5.17×10-4) were statistically significantly associated with CCT.
Conclusions: The targeted GWAS identified four genes (DKK1, DKK2, RYK, and FZD8) with novel associations with CCT and confirmed known associations with two genes, FOXO1 and TCF7L2. All six participate in the Wnt pathway, supporting a broader role for Wnt signaling in regulating the thickness of the cornea. In parallel, this study demonstrated that a hypothesis-driven candidate gene approach can identify associations in existing GWAS data sets.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/genetics
Fulltext Lyophilised Platelet-Rich Fibrin: Physical and Biological Characterisation

Ngah NA, Dias GJ, Tong DC, Mohd Noor SNF, Ratnayake J, Cooper PR, et al.

Molecules, 2021 Nov 25;26(23).
PMID: 34885714 DOI: 10.3390/molecules26237131

BACKGROUND: Platelet-rich fibrin (PRF) has gained popularity in craniofacial surgery, as it provides an excellent reservoir of autologous growth factors (GFs) that are essential for bone regeneration. However, the low elastic modulus, short-term clinical application, poor storage potential and limitations in emergency therapy use restrict its more widespread clinical application. This study fabricates lyophilised PRF (Ly-PRF), evaluates its physical and biological properties, and explores its application for craniofacial tissue engineering purposes.
MATERIAL AND METHODS: A lyophilisation method was applied, and the outcome was evaluated and compared with traditionally prepared PRF. We investigated how lyophilisation affected PRF's physical characteristics and biological properties by determining: (1) the physical and morphological architecture of Ly-PRF using SEM, and (2) the kinetic release of PDGF-AB using ELISA.
RESULTS: Ly-PRF exhibited a dense and homogeneous interconnected 3D fibrin network. Moreover, clusters of morphologically consistent cells of platelets and leukocytes were apparent within Ly-PRF, along with evidence of PDGF-AB release in accordance with previously reports.
CONCLUSIONS: The protocol established in this study for Ly-PRF preparation demonstrated versatility, and provides a biomaterial with growth factor release for potential use as a craniofacial bioscaffold.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/metabolism; Intercellular Signaling Peptides and Proteins/therapeutic use; Intercellular Signaling Peptides and Proteins/chemistry*
Fulltext Immunological history governs human stem cell memory CD4 heterogeneity via the Wnt signaling pathway

Kared H, Tan SW, Lau MC, Chevrier M, Tan C, How W, et al.

Nat Commun, 2020 02 10;11(1):821.
PMID: 32041953 DOI: 10.1038/s41467-020-14442-6

The diversity of the naïve T cell repertoire drives the replenishment potential and capacity of memory T cells to respond to immune challenges. Attrition of the immune system is associated with an increased prevalence of pathologies in aged individuals, but whether stem cell memory T lymphocytes (TSCM) contribute to such attrition is still unclear. Using single cells RNA sequencing and high-dimensional flow cytometry, we demonstrate that TSCM heterogeneity results from differential engagement of Wnt signaling. In humans, aging is associated with the coupled loss of Wnt/β-catenin signature in CD4 TSCM and systemic increase in the levels of Dickkopf-related protein 1, a natural inhibitor of the Wnt/β-catenin pathway. Functional assays support recent thymic emigrants as the precursors of CD4 TSCM. Our data thus hint that reversing TSCM defects by metabolic targeting of the Wnt/β-catenin pathway may be a viable approach to restore and preserve immune homeostasis in the context of immunological history.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/metabolism
Fulltext Genome-wide meta-analysis identifies five new susceptibility loci for pancreatic cancer

Klein AP, Wolpin BM, Risch HA, Stolzenberg-Solomon RZ, Mocci E, Zhang M, et al.

Nat Commun, 2018 02 08;9(1):556.
PMID: 29422604 DOI: 10.1038/s41467-018-02942-5

In 2020, 146,063 deaths due to pancreatic cancer are estimated to occur in Europe and the United States combined. To identify common susceptibility alleles, we performed the largest pancreatic cancer GWAS to date, including 9040 patients and 12,496 controls of European ancestry from the Pancreatic Cancer Cohort Consortium (PanScan) and the Pancreatic Cancer Case-Control Consortium (PanC4). Here, we find significant evidence of a novel association at rs78417682 (7p12/TNS3, P = 4.35 × 10-8). Replication of 10 promising signals in up to 2737 patients and 4752 controls from the PANcreatic Disease ReseArch (PANDoRA) consortium yields new genome-wide significant loci: rs13303010 at 1p36.33 (NOC2L, P = 8.36 × 10-14), rs2941471 at 8q21.11 (HNF4G, P = 6.60 × 10-10), rs4795218 at 17q12 (HNF1B, P = 1.32 × 10-8), and rs1517037 at 18q21.32 (GRP, P = 3.28 × 10-8). rs78417682 is not statistically significantly associated with pancreatic cancer in PANDoRA. Expression quantitative trait locus analysis in three independent pancreatic data sets provides molecular support of NOC2L as a pancreatic cancer susceptibility gene.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins
Fulltext Significant Decreased Expressions of CaN, VEGF, SLC39A6 and SFRP1 in MDA-MB-231 Xenograft Breast Tumor Mice Treated with Moringa oleifera Leaves and Seed Residue (MOLSr) Extracts

Lim WF, Mohamad Yusof MI, Teh LK, Salleh MZ

Nutrients, 2020 Sep 30;12(10).
PMID: 33007803 DOI: 10.3390/nu12102993

Moringa oleifera is a miracle plant with many nutritional and medicinal properties. Chemopreventive values of the combined mixture of moringa leaves and seed residue (MOLSr) at different ratios (M1S9, M1S1 and M9S1) were investigated. MOLSr extracts were subjected to phytochemical screening, antioxidant assays, metabolite profiling and cytotoxic activity on the primary mammary epithelial cells (PMECs), non-malignant Chang's liver cells and various human cancer cell lines (including breast, cervical, colon and liver cancer cell lines). The MOLSr ratio with the most potent cytotoxic activity was used in xenograft mice injected with MDA-MB-231 cells for in vivo tumorigenicity study as well as further protein and gene expression studies. M1S9, specifically composed of saponin and amino acid, retained the lowest antioxidant activity but the highest glucosinolate content as compared to other ratios. Cell viability decreased significantly in MCF-7 breast cancer cells and PMECs after treatment with M1S9. Solid tumor from MDA-MB-231 xenograft mice was inhibited by up to 64.5% at third week after treatment with high-dose M1S9. High-dose M1S9 significantly decreased the expression of calcineurin (CaN) and vascular endothelial cell growth factor (VEGF) proteins as well as the secreted frizzled-related protein 1 (SFRP1) and solute carrier family 39 member 6 (SLC39A6) genes. This study provides new scientific evidence for the chemoprevention potential of MOLSr extracts in a breast cancer model; however, the precise mechanism warrants further investigation.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins
Notch4 overexpression in ameloblastoma correlates with the solid/multicystic phenotype

Siar CH, Nagatsuka H, Chuah KS, Rivera RS, Nakano K, Ng KH, et al.

Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 2010 Aug;110(2):224-33.
PMID: 20659700 DOI: 10.1016/j.tripleo.2010.03.009

Notch signaling has been implicated in cell fate decisions during odontogenesis and tumorigenesis of some odontogenic neoplasms; however, its role in solid/multicystic (SA), unicystic (UA), and recurrent (RA) ameloblastoma remains unclear. The aim of this study was to determine Notch receptor and ligand expressions in these subtypes and to speculate on their significance.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/biosynthesis*; Intercellular Signaling Peptides and Proteins/genetics
Solubilized antigen of Blastocystis hominis facilitates the growth of human colorectal cancer cells, HCT116

Chandramathi S, Suresh K, Kuppusamy UR

Parasitol Res, 2010 Mar;106(4):941-5.
PMID: 20165878 DOI: 10.1007/s00436-010-1764-7

Blastocystis hominis is one of the most common intestinal protozoan parasites in humans, and reports have shown that blastocystosis is coupled with intestinal disorders. In the past, researchers have developed an in vitro model using B. hominis culture filtrates to investigate its ability in triggering inflammatory cytokine responses and transcription factors in human colonic epithelial cells. Studies have also correlated the inflammation by parasitic infection with cancer. The present study provides evidence of the parasite facilitating cancer cell growth through observing the cytopathic effect, cellular immunomodulation, and apoptotic responses of B. hominis, especially in malignancy. Here we investigated the effect of solubilized antigen from B. hominis on cell viability, using peripheral blood mononuclear cells (PBMCs) and human colorectal carcinoma cells (HCT116). The gene expressions of cytokines namely interleukin 6 (IL-6), IL-8, tumor necrosis factor alpha, interferon gamma, nuclear factor kappa light-chain enhancer of activated B cells (a gene transcription factor), and proapoptotic genes namely protein 53 and cathepsin B were also studied. Results exhibited favor the fact that antigen from B. hominis, at a certain concentration, could facilitate the growth of HCT116 while having the ability to downregulate immune cell responses (PBMCs). Therefore, there is a vital need to screen colorectal cancer patients for B. hominis infection as it possesses the ability to enhance the tumor growth.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/pharmacology*
Fulltext Early clearance of Chikungunya virus in children is associated with a strong innate immune response

Simarmata D, Ng DC, Kam YW, Lee B, Sum MS, Her Z, et al.

Sci Rep, 2016 05 16;6:26097.
PMID: 27180811 DOI: 10.1038/srep26097

Chikungunya fever (CHIKF) is a global infectious disease which can affect a wide range of age groups. The pathological and immunological response upon Chikungunya virus (CHIKV) infection have been reported over the last few years. However, the clinical profile and immune response upon CHIKV infection in children remain largely unknown. In this study, we analyzed the clinical and immunological response, focusing on the cytokine/chemokine profile in a CHIKV-infected pediatric cohort from Sarawak, Malaysia. Unique immune mediators triggered upon CHIKV infection were identified through meta-analysis of the immune signatures between this pediatric group and cohorts from previous outbreaks. The data generated from this study revealed that a broad spectrum of cytokines/chemokines is up-regulated in a sub-group of virus-infected children stratified according to their viremic status during hospitalization. Furthermore, different immune mediator profiles (the levels of pro-inflammatory cytokines, chemokines and growth and other factors) were observed between children and adults. This study gives an important insight to understand the immune response of CHIKV infection in children and would aid in the development of better prognostics and clinical management for children.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/metabolism
Inducible transgene expression in undifferentiated mouse embryonic stem cells and embryoid bodies

Nordin N, Nathan S, Li M, Mason JO

Med J Malaysia, 2008 Jul;63 Suppl A:59-60.
PMID: 19024983

Obtaining pure population of neural cells from embryonic stem (ES) cells remains a challenge as little is known about the genes that govern embryonic stem cell differentiation. Using mouse ES cells, we aim to uncover the mechanisms that regulate neural differentiation of ES cells by focusing on roles played by Wnt family genes. Combining two techniques, Cre/loxP-based genetic recombination and ligand-dependent activation of Cre, we have generated transgenic ES cell lines that allow for the temporal control of expression and activity of Wnt gene (Wnt1-Ha) and Wnt antagonist (Dkk1). The ability of these cell lines in inducing the expression of transgene in undifferentiated ES cells and, more importantly, in differentiated derivatives of ES cells in vitro is evaluated.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/genetics
Fulltext Effect of Growth Factor Supplementation on the Hair Cell Specific Markers of Cells Harvested from Basilar Membrane

Ubaidah MA, Chua KH, Ami M, Zainal A, Saim A, Saim L, et al.

J Int Adv Otol, 2015 Apr;11(1):23-9.
PMID: 26223713 DOI: 10.5152/iao.2015.539

Loss of auditory hair cells is a major cause of deafness. The presence of auditory progenitor cells in the inner ear raises the hope for mammalian inner ear cell regeneration. In this study, we aimed to investigate the effect of growth factor supplementations, namely a combination of epidermal growth factor (EGF), insulin-like growth factor (IGF), and beta (β)-fibroblast growth factor (βFGF), on the expression of hair cell-specific markers by cells harvested from the cochlear membrane. This would provide an insight into the capability of these cells to differentiate into hair cells.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/pharmacology*

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