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δ- and γ-tocotrienols induce classical ultrastructural apoptotic changes in human T lymphoblastic leukemic cells

Wong RS, Radhakrishnan AK, Ibrahim TA, Cheong SK

Microsc Microanal, 2012 Jun;18(3):462-9.
PMID: 22640960 DOI: 10.1017/S1431927612000177

Tocotrienols are isomers of the vitamin E family, which have been reported to exert cytotoxic effects in various cancer cells. Although there have been some reports on the effects of tocotrienols in leukemic cells, ultrastructural evidence of tocotrienol-induced apoptotic cell death in leukemic cells is lacking. The present study investigated the effects of three isomers of tocotrienols (alpha, delta, and gamma) on a human T lymphoblastic leukemic cell line (CEM-SS). Cell viability assays showed that all three isomers had cytotoxic effects (p < 0.05) on CEM-SS cells with delta-tocotrienol being the most potent. Transmission electron microscopy showed that the cytotoxic effects by delta- and gamma-tocotrienols were through the induction of an apoptotic pathway as demonstrated by the classical ultrastructural apoptotic changes characterized by peripheral nuclear chromatin condensation and nuclear fragmentation. These findings were confirmed biochemically by the demonstration of phosphatidylserine externalization via flow cytometry analysis. This is the first study showing classical ultrastructural apoptotic changes induced by delta- and gamma-tocotrienols in human T lymphoblastic leukemic cells.

Matched MeSH terms: Cell Nucleus/ultrastructure
Fulltext [Zinc induces normoxic accumulation of transcriptionally active hypoxia-inducible factor 1-alpha in mammary epithelial cells]

Lee SY, Mustafa S, Ching YW, Shafee N

Mol Biol (Mosk), 2017 3 3;51(1):104-110.
PMID: 28251972 DOI: 10.7868/S0026898417010116

Both zinc and the α-subunit of hypoxia-inducible factor (HIF-1α) play important roles in the remodelling of mammary gland tissues. In the present study, we examined the level and the transcriptional activity of HIF-1α in mammary cells upon zinc treatment. In MCF-7 mammary adenocarcinoma and MCF-10A mammary epithelial cell lines, the toxicity levels of zinc differ. Interestingly, both cell lines overexpress HIF-1α following zinc treatment. As it was evident from an up-regulation of its specific target gene CA9 that encodes carbonic anhydrase IX, the stabilized HIF-1α translocated to the nucleus and was transcriptionally active. Hence, we conclude that zinc causes normoxic accumulation of transcriptionally active HIF-1α by interfering with its post-translational regulation.

Matched MeSH terms: Cell Nucleus
Toward understanding the distribution of Laurasian frogs: a test of Savage's biogeographical hypothesis using the genus Bombina

Zheng Y, Fu J, Li S

Mol Phylogenet Evol, 2009 Jul;52(1):70-83.
PMID: 19348953 DOI: 10.1016/j.ympev.2009.03.026

Several anuran groups of Laurasian origin are each co-distributed in four isolated regions of the Northern Hemisphere: central/southern Europe and adjacent areas, Korean Peninsula and adjacent areas, Indo-Malaya, and southern North America. Similar distribution patterns have been observed in diverse animal and plant groups. Savage [Savage, J.M., 1973. The geographic distribution of frogs: patterns and predictions. In: Vial, J.L. (Ed.), Evolutionary Biology of the Anurans. University of Missouri Press, Columbia, pp. 351-445] hypothesized that the Miocene global cooling and increasing aridities in interiors of Eurasia and North America caused a southward displacement and range contraction of Laurasian frogs (and other groups). We use the frog genus Bombina to test Savage's biogeographical hypothesis. A phylogeny of Bombina is reconstructed based on three mitochondrial and two nuclear gene fragments. The genus is divided into three major clades: an Indo-Malaya clade includes B. fortinuptialis, B. lichuanensis, B. maxima, and B. microdeladigitora; a European clade includes B. bombina, B. pachypus, and B. variegata; and a Korean clade contains B. orientalis. The European and Korean clades form sister-group relationship. Molecular dating of the phylogenetic tree using the penalized likelihood and Bayesian analyses suggests that the divergence between the Indo-Malaya clade and other Bombina species occurred 5.9-28.6 million years ago. The split time between the European clade and the Korean clade is estimated at 5.1-20.9 million years ago. The divergence times of these clades are not significantly later than the timing of Miocene cooling and drying, and therefore can not reject Savage's hypothesis. Some other aspects of biogeography of Bombina also are discussed. The Korean Peninsula and the Shandong Peninsula might have supplied distinct southern refugia for B. orientalis during the Pleistocene glacial maxima. In the Indo-Malaya clade, the uplift of the Tibetan Plateau might have promoted the split between B. maxima and the other species.

Matched MeSH terms: Cell Nucleus/genetics
Fulltext The structure and low-lying energetic states of 160-162dy isotopes

Noora Rosli, Okhunov, A.A., Hasan Abu Kassim

Journal of Nuclear and Related Technologies, 2012;2012(2):14-21.
MyJurnal

160-162 Dy
nuclei are the best candidates to study collective properties of low-lying states since these
nuclei are quite well studied experimentally. Phenomenological model is used to evaluate the positive-parity states energy spectra and the structure of these nuclei by taking into account the Coriolis mixing between states. Deviations from the adiabatic conditions are found to be occurred.

Matched MeSH terms: Cell Nucleus
The pineal gland of equatorial mammals. I. The pinealocytes of the Malaysian Rat (Rattus sabanus)

Pévet P, Yadav M

Cell Tissue Res, 1980;210(3):417-33.
PMID: 7407847

The ultrastructure of the pinealocytes of the Malaysian rat (Rattus sabanus), a mammal inhabiting a zone near the equator where the annual variations of daylength are inconspicuous, was examined and compared with that of pinealocytes of other mammals. On the basis of the presence of granular vesicles, only one population of pinealocytes was found. A large number of granular vesicles and vesicle-crowned rodlets is characteristic of the pinealocytes of this equatorial species. Vesicle-crowned rodlets are especially numerous in the endings of the pinealocyte processes and; they most often found in direct topographical connection with the perivascular spaces. The physiological significance of the presence of such large amounts of vesicle-crowned rodlets and of the secretory process characterized by the formation of granular vesicles is discussed.

Matched MeSH terms: Cell Nucleus/ultrastructure
Fulltext The genetic intractability of Symbiodinium microadriaticum to standard algal transformation methods

Chen JE, Barbrook AC, Cui G, Howe CJ, Aranda M

PLoS One, 2019;14(2):e0211936.
PMID: 30779749 DOI: 10.1371/journal.pone.0211936

Modern transformation and genome editing techniques have shown great success across a broad variety of organisms. However, no study of successfully applied genome editing has been reported in a dinoflagellate despite the first genetic transformation of Symbiodinium being published about 20 years ago. Using an array of different available transformation techniques, we attempted to transform Symbiodinium microadriaticum (CCMP2467), a dinoflagellate symbiont of reef-building corals, with the view to performing subsequent CRISPR-Cas9 mediated genome editing. Plasmid vectors designed for nuclear transformation containing the chloramphenicol resistance gene under the control of the CaMV p35S promoter as well as several putative endogenous promoters were used to test a variety of transformation techniques including biolistics, electroporation and agitation with silicon carbide whiskers. Chloroplast-targeted transformation was attempted using an engineered Symbiodinium chloroplast minicircle encoding a modified PsbA protein expected to confer atrazine resistance. We report that we have been unable to confer chloramphenicol or atrazine resistance on Symbiodinium microadriaticum strain CCMP2467.

Matched MeSH terms: Cell Nucleus/genetics*; Cell Nucleus/metabolism
The complex phylogeography of the Indo-Malayan Alophoixus bulbuls with the description of a putative new ring species complex

Fuchs J, Ericson PG, Bonillo C, Couloux A, Pasquet E

Mol Ecol, 2015 Nov;24(21):5460-74.
PMID: 26224534 DOI: 10.1111/mec.13337

The Indo-Malayan bioregion has provided some of the most spectacular discoveries of new vertebrate species (e.g. saola, khanyou, bare-faced bulbul) over the last 25 years. Yet, very little is known about the processes that led to the current biodiversity in this region. We reconstructed the phylogeographic history of a group of closely related passerines, the Alophoixus bulbuls. These birds are continuously distributed in Indo-Malaya around the Thailand lowlands such that their distribution resembles a ring. Our analyses revealed a single colonization event of the mainland from Sundaland with sequential divergence of taxa from southwest to northeast characterized by significant gene flow between parapatric taxa, and reduced or ancient gene flow involving the two taxa at the extremities of the ring. We detected evidence of population expansion in two subspecies, including one that was involved in the closing of the ring. Hence, our analyses indicate that the diversification pattern of Alophoixus bulbuls fits a ring species model driven by geographic isolation. To our knowledge, the Alophoixus bulbuls represent the first case of a putative broken ring species complex in Indo-Malaya. We also discuss the implications of our results on our understanding of the biogeography in Indo-Malaya.

Matched MeSH terms: Cell Nucleus/genetics
Fulltext The antimicrobial polymer PHMB enters cells and selectively condenses bacterial chromosomes

Chindera K, Mahato M, Kumar Sharma A, Horsley H, Kloc-Muniak K, Kamaruzzaman NF, et al.

Sci Rep, 2016;6:23121.
PMID: 26996206 DOI: 10.1038/srep23121

To combat infection and antimicrobial resistance, it is helpful to elucidate drug mechanism(s) of action. Here we examined how the widely used antimicrobial polyhexamethylene biguanide (PHMB) kills bacteria selectively over host cells. Contrary to the accepted model of microbial membrane disruption by PHMB, we observed cell entry into a range of bacterial species, and treated bacteria displayed cell division arrest and chromosome condensation, suggesting DNA binding as an alternative antimicrobial mechanism. A DNA-level mechanism was confirmed by observations that PHMB formed nanoparticles when mixed with isolated bacterial chromosomal DNA and its effects on growth were suppressed by pairwise combination with the DNA binding ligand Hoechst 33258. PHMB also entered mammalian cells, but was trapped within endosomes and excluded from nuclei. Therefore, PHMB displays differential access to bacterial and mammalian cellular DNA and selectively binds and condenses bacterial chromosomes. Because acquired resistance to PHMB has not been reported, selective chromosome condensation provides an unanticipated paradigm for antimicrobial action that may not succumb to resistance.

Matched MeSH terms: Cell Nucleus
The aminopeptidase inhibitor, z-L-CMK, is toxic and induces cell death in Jurkat T cells through oxidative stress

Yeo EH, Goh WL, Chow SC

Toxicol. Mech. Methods, 2018 Mar;28(3):157-166.
PMID: 28849708 DOI: 10.1080/15376516.2017.1373882

The leucine aminopeptidase inhibitor, benzyloxycarbonyl-leucine-chloromethylketone (z-L-CMK), was found to be toxic and readily induce cell death in Jurkat T cells. Dose-response studies show that lower concentration of z-L-CMK induced apoptosis in Jurkat T cells whereas higher concentration causes necrosis. In z-L-CMK-induced apoptosis, both the initiator caspases (-8 and -9) and effector caspases (-3 and -6) were processed to their respective subunits. However, the caspases remained intact in z-L-CMK-induced necrosis. The caspase inhibitor, z-VAD-FMK inhibited z-L-CMK-mediated apoptosis and caspase processing but has no effect on z-L-CMK-induced necrosis in Jurkat T cells. The high mobility group protein B1 (HMGB1) protein was found to be released into the culture medium by the necrotic cells and not the apoptotic cells. These results indicate that the necrotic cell death mediated by z-L-CMK at high concentrations is via classical necrosis rather than secondary necrosis. We also demonstrated that cell death mediated by z-L-CMK was associated with oxidative stress via the depletion of intracellular glutathione (GSH) and increase in reactive oxygen species (ROS), which was blocked by N-acetyl cysteine. Taken together, the results demonstrated that z-L-CMK is toxic to Jurkat T cells and induces apoptosis at low concentrations, while at higher concentrations the cells die of necrosis. The toxic side effects in Jurkat T cells mediated by z-L-CMK are associated with oxidative stress via the depletion of GSH and accumulation of ROS.

Matched MeSH terms: Cell Nucleus Shape/drug effects
Fulltext Systematic revision of the genus Peronia Fleming, 1822 (Gastropoda, Euthyneura, Pulmonata, Onchidiidae)

Dayrat B, Goulding TC, Apte D, Aslam S, Bourke A, Comendador J, et al.

Zookeys, 2020;972:1-224.
PMID: 33071542 DOI: 10.3897/zookeys.972.52853

The genus Peronia Fleming, 1822 includes all the onchidiid slugs with dorsal gills. Its taxonomy is revised for the first time based on a large collection of fresh material from the entire Indo-West Pacific, from South Africa to Hawaii. Nine species are supported by mitochondrial (COI and 16S) and nuclear (ITS2 and 28S) sequences as well as comparative anatomy. All types available were examined and the nomenclatural status of each existing name in the genus is addressed. Of 31 Peronia species-group names available, 27 are regarded as invalid (twenty-one synonyms, sixteen of which are new, five nomina dubia, and one homonym), and four as valid: Peronia peronii (Cuvier, 1804), Peronia verruculata (Cuvier, 1830), Peronia platei (Hoffmann, 1928), and Peronia madagascariensis (Labbé, 1934a). Five new species names are created: P. griffithsi Dayrat & Goulding, sp. nov., P. okinawensis Dayrat & Goulding, sp. nov., P. setoensis Dayrat & Goulding, sp. nov., P. sydneyensis Dayrat & Goulding, sp. nov., and P. willani Dayrat & Goulding, sp. nov.Peronia species are cryptic externally but can be distinguished using internal characters, with the exception of P. platei and P. setoensis. The anatomy of most species is described in detail here for the first time. All the secondary literature is commented on and historical specimens from museum collections were also examined to better establish species distributions. The genus Peronia includes two species that are widespread across the Indo-West Pacific (P. verruculata and P. peronii) as well as endemic species: P. okinawensis and P. setoensis are endemic to Japan, and P. willani is endemic to Northern Territory, Australia. Many new geographical records are provided, as well as a key to the species using morphological traits.

Matched MeSH terms: Cell Nucleus
Fulltext Survival and Intra-Nuclear Trafficking of Burkholderia pseudomallei: Strategies of Evasion from Immune Surveillance?

Vadivelu J, Vellasamy KM, Thimma J, Mariappan V, Kang WT, Choh LC, et al.

PLoS Negl Trop Dis, 2017 01;11(1):e0005241.
PMID: 28045926 DOI: 10.1371/journal.pntd.0005241

BACKGROUND: During infection, successful bacterial clearance is achieved via the host immune system acting in conjunction with appropriate antibiotic therapy. However, it still remains a tip of the iceberg as to where persistent pathogens namely, Burkholderia pseudomallei (B. pseudomallei) reside/hide to escape from host immune sensors and antimicrobial pressure.
METHODS: We used transmission electron microscopy (TEM) to investigate post-mortem tissue sections of patients with clinical melioidosis to identify the localisation of a recently identified gut microbiome, B. pseudomallei within host cells. The intranuclear presence of B. pseudomallei was confirmed using transmission electron microscopy (TEM) of experimentally infected guinea pig spleen tissues and Live Z-stack, and ImageJ analysis of fluorescence microscopy analysis of in vitro infection of A549 human lung epithelial cells.
RESULTS: TEM investigations revealed intranuclear localization of B. pseudomallei in cells of infected human lung and guinea pig spleen tissues. We also found that B. pseudomallei induced actin polymerization following infection of A549 human lung epithelial cells. Infected A549 lung epithelial cells using 3D-Laser scanning confocal microscopy (LSCM) and immunofluorescence microscopy confirmed the intranuclear localization of B. pseudomallei.
CONCLUSION: B. pseudomallei was found within the nuclear compartment of host cells. The nucleus may play a role as an occult or transient niche for persistence of intracellular pathogens, potentially leading to recurrrent episodes or recrudescence of infection.

Matched MeSH terms: Cell Nucleus/microbiology*
Fulltext Subditine, a new monoterpenoid indole alkaloid from bark of Nauclea subdita (Korth.) Steud. induces apoptosis in human prostate cancer cells

Liew SY, Looi CY, Paydar M, Cheah FK, Leong KH, Wong WF, et al.

PLoS One, 2014;9(2):e87286.
PMID: 24551054 DOI: 10.1371/journal.pone.0087286

In this study, a new apoptotic monoterpenoid indole alkaloid, subditine (1), and four known compounds were isolated from the bark of Nauclea subdita. Complete (1)H- and (13)C- NMR data of the new compound were reported. The structures of isolated compounds were elucidated with various spectroscopic methods such as 1D- and 2D- NMR, IR, UV and LCMS. All five compounds were screened for cytotoxic activities on LNCaP and PC-3 human prostate cancer cell-lines. Among the five compounds, the new alkaloid, subditine (1), demonstrated the most potent cell growth inhibition activity and selective against LNCaP with an IC50 of 12.24±0.19 µM and PC-3 with an IC50 of 13.97±0.32 µM, compared to RWPE human normal epithelial cell line (IC50 = 30.48±0.08 µM). Subditine (1) treatment induced apoptosis in LNCaP and PC-3 as evidenced by increased cell permeability, disruption of cytoskeletal structures and increased nuclear fragmentation. In addition, subditine (1) enhanced intracellular reactive oxygen species (ROS) production, as reflected by increased expression of glutathione reductase (GR) to scavenge damaging free radicals in both prostate cancer cell-lines. Excessive ROS could lead to disruption of mitochondrial membrane potential (MMP), release of cytochrome c and subsequent caspase 9, 3/7 activation. Further Western blot analyses showed subditine (1) induced down-regulation of Bcl-2 and Bcl-xl expression, whereas p53 was up-regulated in LNCaP (p53-wild-type), but not in PC-3 (p53-null). Overall, our data demonstrated that the new compound subditine (1) exerts anti-proliferative effect on LNCaP and PC-3 human prostate cancer cells through induction of apoptosis.

Matched MeSH terms: Cell Nucleus/drug effects; Cell Nucleus/metabolism
Subcellular localization of leptin and leptin receptor in breast cancer detected in an electron microscopic study

Al-Shibli SM, Amjad NM, Al-Kubaisi MK, Mizan S

Biochem Biophys Res Commun, 2017 Jan 22;482(4):1102-1106.
PMID: 27914811 DOI: 10.1016/j.bbrc.2016.11.165

Leptin (LEP) and leptin receptor (LEPR) have long been found associated with breast cancer. So far no high-resolution method such as electron microscopy has been used to investigate the subcellular localization of leptin and leptin receptor in breast cancer. We collected cancer and non-cancer breast tissues from 51 women with invasive ductal breast cancer. Leptin and leptin receptor in the tissues were estimated using immunohistochemistry (IHC). LEP and LEPR were localized at subcellular level by immunocytochemistry (ICC) using ultra-fine gold particle conjugated antibody, and visualized with transmission electron microscopy (TEM). IHC showed high presence of LEP and LEPR in 65% and 67% respectively of the breast cancer samples, 100% and 0% respectively of the adipose tissue samples, and no high presence in the non-cancer breast tissue samples. On TEM views both LEP and LEPR were found highly concentrated within the nucleus of the cancer cells, indicating that nucleus is the principal seat of action. However, presence of high concentration of LEP does not necessarily prove its over-expression, as often concluded, because LEP could be internalized from outside by LEPR in the cells. In contrast, LEPR is definitely over-expressed in the ductal breast cancer cells. Therefore, we hypothesize that over-expression of LEPR, rather than that of LEP has a fundamental role in breast carcinogenesis in particular, and probably for LEP-LEPR associated tumors in general.

Matched MeSH terms: Cell Nucleus/metabolism
Styryl-lactone goniothalamin inhibits TNF-α-induced NF-κB activation

Orlikova B, Schumacher M, Juncker T, Yan CC, Inayat-Hussain SH, Hajjouli S, et al.

Food Chem Toxicol, 2013 Sep;59:572-8.
PMID: 23845509 DOI: 10.1016/j.fct.2013.06.051

(R)-(+)-Goniothalamin (GTN), a styryl-lactone isolated from the medicinal plant Goniothalamus macrophyllus, exhibits pharmacological activities including cytotoxic and anti-inflammatory effects. In this study, GTN modulated TNF-α induced NF-κB activation. GTN concentrations up to 20 μM showed low cytotoxic effects in K562 chronic myelogenous leukemia and in Jurkat T cells. Importantly, at these concentrations, no cytotoxicity was observed in healthy peripheral blood mononuclear cells. Our results confirmed that GTN inhibited tumor necrosis factor-α (TNF-α)-induced NF-κB activation in Jurkat and K562 leukemia cells at concentrations as low as 5 μM as shown by reporter gene assays and western blots. Moreover, GTN down-regulated translocation of the p50/p65 heterodimer to the nucleus, prevented binding of NF-κB to its DNA response element and reduced TNF-α-activated interleukin-8 (IL-8) expression. In conclusion, GTN inhibits TNF-α-induced NF-κB activation at non-apoptogenic concentrations in different leukemia cell models without presenting toxicity towards healthy blood cells underlining the anti-leukemic potential of this natural compound.

Matched MeSH terms: Cell Nucleus/drug effects; Cell Nucleus/metabolism
Sex chromatin positive nuclei in the nasal smears of the females

Sen Gupta BN

Med J Malaya, 1968 Sep;23(1):32-4.
PMID: 4237553
Matched MeSH terms: Cell Nucleus*
Fulltext Secondary Sea-Blue Histiocytosis in a Patient with Transfusion Dependent HbE-Beta Thalassaemia and Osteosarcoma

Saad Eldeen Bakheet O, Yusof N, Raja Zahratul A, Ithnin A, Abdul Aziz S, Alias H

Indian J Hematol Blood Transfus, 2016 Jun;32(Suppl 1):262-6.
PMID: 27408409 DOI: 10.1007/s12288-015-0582-6

Secondary sea-blue histiocytosis occurs more frequently than the primary form and occurs consequent to a wide range of metabolic and haematologic disorders including thalassaemia. We report an 18-year-old Chinese boy with transfusion-dependent HbE-beta thalassaemia who complained of pain and swelling at the left iliac crest region for 2 months duration. Physical examination revealed pallor with hepatosplenomegaly. Local examination revealed a huge swelling 12 cm × 12 cm in diameter, firm in consistency and tender. Histopathological examination of the mass revealed an osteosarcoma. His bone marrow aspirate showed numerous sea-blue histiocytes, the cytoplasm of which was closely packed with fine granules that stained blue with May-Grunwald-Giemsa. The nuclei were centrally located in some cells and displaced towards the periphery in other cells. There was no malignant cell infiltration in the marrow. The case is reported due to the co-incidental dual pathology in our patient (HbE-beta thalassaemia and osteosarcoma) and the unusual bone marrow finding of numerous sea-blue histiocytes.

Matched MeSH terms: Cell Nucleus
Fulltext Sciatic nerve repair with tissue engineered nerve: Olfactory ensheathing cells seeded poly(lactic-co-glygolic acid) conduit in an animal model

Tan CW, Ng MH, Ohnmar H, Lokanathan Y, Nur-Hidayah H, Roohi SA, et al.

Indian J Orthop, 2013 Nov;47(6):547-52.
PMID: 24379458 DOI: 10.4103/0019-5413.121572

BACKGROUND AND AIM: Synthetic nerve conduits have been sought for repair of nerve defects as the autologous nerve grafts causes donor site morbidity and possess other drawbacks. Many strategies have been investigated to improve nerve regeneration through synthetic nerve guided conduits. Olfactory ensheathing cells (OECs) that share both Schwann cell and astrocytic characteristics have been shown to promote axonal regeneration after transplantation. The present study was driven by the hypothesis that tissue-engineered poly(lactic-co-glycolic acid) (PLGA) seeded with OECs would improve peripheral nerve regeneration in a long sciatic nerve defect.
MATERIALS AND METHODS: Sciatic nerve gap of 15 mm was created in six adult female Sprague-Dawley rats and implanted with PLGA seeded with OECs. The nerve regeneration was assessed electrophysiologically at 2, 4 and 6 weeks following implantation. Histopathological examination, scanning electron microscopic (SEM) examination and immunohistochemical analysis were performed at the end of the study.
RESULTS: Nerve conduction studies revealed a significant improvement of nerve conduction velocities whereby the mean nerve conduction velocity increases from 4.2 ΁ 0.4 m/s at week 2 to 27.3 ΁ 5.7 m/s at week 6 post-implantation (P < 0.0001). Histological analysis revealed presence of spindle-shaped cells. Immunohistochemical analysis further demonstrated the expression of S100 protein in both cell nucleus and the cytoplasm in these cells, hence confirming their Schwann-cell-like property. Under SEM, these cells were found to be actively secreting extracellular matrix.
CONCLUSION: Tissue-engineered PLGA conduit seeded with OECs provided a permissive environment to facilitate nerve regeneration in a small animal model.

Matched MeSH terms: Cell Nucleus
Fulltext Resveratrol treatment reveals a novel role for HMGB1 in regulation of the type 1 interferon response in dengue virus infection

Zainal N, Chang CP, Cheng YL, Wu YW, Anderson R, Wan SW, et al.

Sci Rep, 2017 02 20;7:42998.
PMID: 28216632 DOI: 10.1038/srep42998

Dengue is one of the most significant mosquito-borne virus diseases worldwide, particularly in tropical and subtropical regions. This study sought to examine the antiviral activity of resveratrol (RESV), a phytoalexin secreted naturally by plants, against dengue virus (DENV) infection. Our data showed that RESV inhibits the translocation of high mobility group box 1 (HMGB1), a DNA binding protein that normally resides in the nucleus, into the cytoplasm and extracellular milieu. HMGB1 migrates out of the nucleus during DENV infection. This migration is inhibited by RESV treatment and is mediated by induction of Sirt1 which leads to the retention of HMGB1 in the nucleus and consequently helps in the increased production of interferon-stimulated genes (ISGs). Nuclear HMGB1 was found to bind to the promoter region of the ISG and positively regulated the expression of ISG. The enhanced transcription of ISGs by nuclear HMGB1 thus contributes to the antiviral activity of RESV against DENV. To the best of our knowledge, this is the first report to demonstrate that RESV antagonizes DENV replication and that nuclear HMGB1 plays a role in regulating ISG production.

Matched MeSH terms: Cell Nucleus/metabolism
Restoring the IL-1β/NF-κB-induced impaired chondrogenesis by diallyl disulfide in human adipose-derived mesenchymal stem cells via attenuation of reactive oxygen species and elevation of antioxidant enzymes

Bahrampour Juybari K, Kamarul T, Najafi M, Jafari D, Sharifi AM

Cell Tissue Res, 2018 08;373(2):407-419.
PMID: 29582166 DOI: 10.1007/s00441-018-2825-y

Strategies based on mesenchymal stem cell (MSC) therapy for restoring injured articular cartilage are not effective enough in osteoarthritis (OA). Due to the enhanced inflammation and oxidative stress in OA microenvironment, differentiation of MSCs into chondrocytes would be impaired. This study aims to explore the effects of diallyl disulfide (DADS) on IL-1β-mediated inflammation and oxidative stress in human adipose derived mesenchymal stem cells (hADSCs) during chondrogenesis. MTT assay was employed to examine the effects of various concentrations of DADS on the viability of hADSCs at different time scales to obtain non-cytotoxic concentration range of DADS. The effects of DADS on IL-1β-induced intracellular ROS generation and lipid peroxidation were evaluated in hADSCs. Western blotting was used to analyze the protein expression levels of IκBα (np), IκBα (p), NF-κB (np) and NF-κB (p). Furthermore, the gene expression levels of antioxidant enzymes in hADSCs and chondrogenic markers at days 7, 14 and 21 of differentiation were measured using qRT-PCR. The results showed that addition of DADS significantly enhanced the mRNA expression levels of antioxidant enzymes as well as reduced ROS elevation, lipid peroxidation, IκBα activation and NF-κB nuclear translocation in hADSCs treated with IL-1β. In addition, DADS could significantly increase the expression levels of IL-1β-induced impaired chondrogenic marker genes in differentiated hADSCs. Treatment with DADS may provide an effective approach to prevent the pro-inflammatory cytokines and oxidative stress as catabolic causes of chondrocyte cell death and enhance the protective anabolic effects by promoting chondrogenesis associated gene expressions in hADSCs exposed to OA condition.

Matched MeSH terms: Cell Nucleus/drug effects; Cell Nucleus/metabolism
Report: Nuclei segmentation of leukocytes in blood smear digital images

Abbas N, Mohamad D, Abdullah AH, Saba T, Al-Rodhaan M, Al-Dhelaan A

Pak J Pharm Sci, 2015 Sep;28(5):1801-6.
PMID: 26408877

The Leukocytes are differentiated from each other on the basis of their nuclei, demanded in many Medical studies, especially in all types of Leukemia by the Hematologists to note the disorder caused by specific type of Leukocyte. Leukemia is a life threatening disease. The work for diagnosing is manually carried out by the Hematologists involving much labor, time and human errors. The problems mentioned are easily addressed through computer vision techniques, but still accuracy and efficiency are demanded in terms of the basic and challenging step segmentation of Leukocyte's nuclei. The underlying study proposed better method in terms of accuracy and efficiency by designing a dynamic convolution filter for boosting low intensity values in the separated green channel of an RGB image and suppressing the high values in the same channel. The high values in the green channel become 255 (background) while the nuclei always have low values in the green channel and thus clearly appear as foreground. The proposed technique is tested on 365 images achieving an overall accuracy of 95.89%, while improving the efficiency by 10%. The proposed technique achieved its targets in a realistic way by improving the accuracy as well as the efficiency and both are highly required in the area.

Matched MeSH terms: Cell Nucleus/ultrastructure*

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