Displaying publications 1281 - 1298 of 1298 in total

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  1. Choudhary S, Jain A, Amin MCIM, Mishra V, Agrawal GP, Kesharwani P
    Colloids Surf B Biointerfaces, 2016 May 01;141:268-277.
    PMID: 26859118 DOI: 10.1016/j.colsurfb.2016.01.048
    The study was intended to develop a new intra-gastric floating in situ microballoons system for controlled delivery of rabeprazole sodium and amoxicillin trihydrate for the treatment of peptic ulcer disease. Eudragit S-100 and hydroxypropyl methyl cellulose based low density microballoons systems were fabricated by employing varying concentrations of Eudragit S-100 and hydroxypropyl methyl cellulose, to which varying concentrations of drug was added, and formulated by stirring at various speed and time to optimize the process and formulation variable. The formulation variables like concentration and ratio of polymers significantly affected the in vitro drug release from the prepared floating device. The validation of the gastro-retentive potential of the prepared microballoons was carried out in rabbits by orally administration of microballoons formulation containing radio opaque material. The developed formulations showed improved buoyancy and lower ulcer index as compared to that seen with plain drugs. Ulcer protective efficacies were confirmed in ulcer-bearing mouse model. In conclusion, greater compatibility, higher gastro-retention and higher anti-ulcer activity of the presently fabricated formulations to improve potential of formulation for redefining ulcer treatment are presented here. These learning exposed a targeted and sustained drug delivery potential of prepared microballoons in gastric region for ulcer therapeutic intervention as corroborated by in vitro and in vivo findings and, thus, deserves further attention for improved ulcer treatment.
    Matched MeSH terms: Microscopy, Electron, Scanning
  2. Gnanaraj C, Shah MD, Makki JS, Iqbal M
    Pharm Biol, 2016 Aug;54(8):1420-33.
    PMID: 26810847 DOI: 10.3109/13880209.2015.1104697
    Context The antioxidative properties of plants or plant derivative products are well known for their free radical scavenging effects. Flagellaria indica L. (Flagellariaceae) (FI) is a tropical medicinal plant used by the natives of Sabah as medication for semi-paralysis. Objective This study evaluates the hepatoprotective mechanism of FI against carbon tetrachloride (CCl4)-mediated liver damage. Materials and methods Aqueous extract of FI leaves was orally administered to adult Sprague-Dawley rats once daily for 14 consecutive days at 300, 400, and 500 mg/kg b.w. prior to CCl4 treatment (1.0 mL/kg b.w.) on the 13th and 14th days. Results Total phenolic content in the aqueous extract of FI leaves was 65.88 ± 1.84 mg gallic acid equivalent/g. IC50 value for free radical scavenging activity of FI aqueous extract was reached at the concentration of 400 μg/mL. Biochemical studies show that the aqueous extract of FI was able to prevent the increase in levels of serum transaminases, alanine aminotransferase, and aspartate aminotransferase (38-74% recovery), and malondialdehyde formation (25-87% recovery) in a dose-dependent manner. Immunohistochemical results evidenced the suppression of oxidative stress markers (4-hydroxynonenal and 8-hydroxydeoxyguanosine) and pro-inflammatory markers (tumour necrosis factor-α, interleukin-6, prostaglandin E2). Histopathological and hepatocyte ultrastructural alterations proved that there were protective effects in FI against CCl4-mediated liver injury. Signs of toxicity were not present in rats treated with FI alone (500 mg/kg b.w.). Discussion and conclusion It can be concluded that the presence of phenolic constituents and their antioxidative effects can be credited to the hepatoprotective activity of FI.
    Matched MeSH terms: Microscopy, Electron, Transmission
  3. Rati Selvaraju T, Khaza'ai H, Vidyadaran S, Sokhini Abd Mutalib M, Ramachandran V, Hamdan Y
    Int J Vitam Nutr Res, 2014;84(3-4):140-51.
    PMID: 26098478 DOI: 10.1024/0300-9831/a000201
    Glutamate is the major mediator of excitatory signals in the mammalian central nervous system. Extreme amounts of glutamate in the extracellular spaces can lead to numerous neurodegenerative diseases. We aimed to clarify the potential of the following vitamin E isomers, tocotrienol-rich fraction (TRF) and α-tocopherol (α-TCP), as potent neuroprotective agents against glutamate-induced injury in neuronal SK-N-SH cells. Cells were treated before and after glutamate injury (pre- and post-treatment, respectively) with 100-300 ng/ml TRF/α-TCP. Exposure to 120 mM glutamate significantly reduced cell viability to 76% and 79% in the pre- and post-treatment studies, respectively; however, pre- and post-treatment with TRF/α-TCP attenuated the cytotoxic effect of glutamate. Compared to the positive control (glutamate-injured cells not treated with TRF/α-TCP), pre-treatment with 100, 200, and 300 ng/ml TRF significantly improved cell viability following glutamate injury to 95.2%, 95.0%, and 95.6%, respectively (p<0.05).The isomers not only conferred neuroprotection by enhancing mitochondrial activity and depleting free radical production, but also increased cell viability and recovery upon glutamate insult. Our results suggest that vitamin E has potent antioxidant potential for protecting against glutamate injury and recovering glutamate-injured neuronal cells. Our findings also indicate that both TRF and α-TCP could play key roles as anti-apoptotic agents with neuroprotective properties.
    Matched MeSH terms: Microscopy, Electron, Scanning
  4. Chua KB, Bellini WJ, Rota PA, Harcourt BH, Tamin A, Lam SK, et al.
    Science, 2000 May 26;288(5470):1432-5.
    PMID: 10827955
    A paramyxovirus virus termed Nipah virus has been identified as the etiologic agent of an outbreak of severe encephalitis in people with close contact exposure to pigs in Malaysia and Singapore. The outbreak was first noted in late September 1998 and by mid-June 1999, more than 265 encephalitis cases, including 105 deaths, had been reported in Malaysia, and 11 cases of encephalitis or respiratory illness with one death had been reported in Singapore. Electron microscopic, serologic, and genetic studies indicate that this virus belongs to the family Paramyxoviridae and is most closely related to the recently discovered Hendra virus. We suggest that these two viruses are representative of a new genus within the family Paramyxoviridae. Like Hendra virus, Nipah virus is unusual among the paramyxoviruses in its ability to infect and cause potentially fatal disease in a number of host species, including humans.
    Matched MeSH terms: Microscopy, Electron
  5. Ho KL, Yusoff K, Seow HF, Tan WS
    J Med Virol, 2003 Jan;69(1):27-32.
    PMID: 12436474
    M13 phages that display random disulfide constrained heptapeptides on their gpIII proteins were used to select for high affinity ligands to hepatitis B core antigen (HBcAg). Phages bearing the amino acid sequences C-WSFFSNI-C and C-WPFWGPW-C were isolated, and a binding assay in solution showed that these phages bind tightly to full-length and truncated HBcAg with K D rel values less than 25 nM, which is at least 10 orders of magnitude higher than phage carrying the peptide sequence LLGRMK selected from a linear peptide library. Both the phages that display the constrained peptides were inhibited from binding to HBcAg particles by a monoclonal antibody that binds specifically to the immunodominant region of the particles. A synthetic heptapeptide with the amino acid sequence WSFFSNI derived from one of the fusion peptides inhibits the binding of large surface antigen (L-HBsAg) to core particles with an IC50 value of 12 +/- 2 microM. This study has identified a smaller peptide with a greater inhibitory effect on L-HBsAg-HBcAg association.
    Matched MeSH terms: Microscopy, Electron
  6. Mohammadi Arvanag F, Bayrami A, Habibi-Yangjeh A, Rahim Pouran S
    Mater Sci Eng C Mater Biol Appl, 2019 Apr;97:397-405.
    PMID: 30678925 DOI: 10.1016/j.msec.2018.12.058
    Green synthesis of ZnO nanoparticles (NPs) using the plants' extract and their potential application have driven a tremendous interest in recent years. This study reports a green microwave-assisted method for synthesis of ZnO NPs using Silybum marianum L. seed extract. Characteristics of the as-prepared sample was explored in terms of crystalline phase, morphology, composition, surface area, optical, and thermal properties. The particles of the biosynthesized sample (ZnO/extract) had smaller sizes than the chemically produced one (ZnO). The existence of biomolecules from Silybum marianum L seed extract linked to the ZnO/extract sample was approved by various analyses. The ZnO/extract sample was used for treating alloxan-induced diabetic rats and its efficiency was compared with ZnO, extract, and insulin treatments. For this purpose, the levels of blood glucose, insulin, total cholesterol, total triglyceride, and high-density lipoprotein were measured before and after treating with the studied treatment agents and compared with each other. Moreover, the antibacterial activities of both ZnO samples were investigated against E. coli to assess their potential antibacterial application. From the results, ZnO/extract NPs represented an outstanding performance in overcoming the diabetic disorders and good antibacterial activity against the studied bacteria.
    Matched MeSH terms: Microscopy, Electron, Scanning
  7. Li HB, You QS, Xu LX, Sun LX, Abdul Majid AS, Xia XB, et al.
    Cell Physiol Biochem, 2017;43(5):2117-2132.
    PMID: 29065394 DOI: 10.1159/000484231
    BACKGROUND/AIMS: The aim of the present study is to investigate the effect of long non-coding RNA-MALAT1 (LncRNA-MALAT1) on retinal ganglion cell (RGC) apoptosis mediated by the PI3K/Akt signaling pathway in rats with glaucoma.

    METHODS: RGCs were isolated and cultured, and monoclonal antibodies (anti-rat Thy-1, Brn3a and RBPMS) were examined by immunocytochemistry. An overexpression vector MALAT1-RNA activation (RNAa), gene knockout vector MALAT1-RNA interference (RNAi), and control vector MALAT1-negative control (NC) were constructed. A chronic high intraocular pressure (IOP) rat model of glaucoma was established by episcleral vein cauterization. The RGCs were divided into the RGC control, RGC pressure, RGC pressure + MALAT1-NC, RGC pressure + MALAT1-RNAi and RGC pressure + MALAT1-RNAa groups. Sixty Sprague-Dawley (SD) rats were randomly divided into the normal, high IOP, high IOP + MALAT1-NC, high IOP + MALAT1-RNAa and high IOP + MALAT1-RNAi groups. qRT-PCR and western blotting were used to detect the expression levels of LncRNA-MALAT1 and PI3K/Akt. Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) and flow cytometry were used to detect RGC apoptosis.

    RESULTS: Immunocytochemistry revealed that the cultured RGCs reached 90% purity. Compared with the RGC pressure + MALAT1-NC group, the RGC pressure + MALAT1-RNAa group exhibited elevated expression levels of MALAT1, lower total protein levels of PI3K and Akt and decreased RGC apoptosis, while these expression levels were reversed in the RGC pressure + MALAT1-RNAi group. RGC numbers and PI3K/Akt expression levels in the high IOP model groups were lower than those in the normal group. In the high IOP + MALAT1-RNAa group, the mRNA and protein expression levels of PI3K/Akt were reduced but higher than those in the other three high IOP model groups. Additionally, RGC numbers in the high IOP + MALAT1-RNAa group were lower than those in the normal group but higher than those in the other three high IOP model groups.

    CONCLUSION: Our study provides evidence that LncRNA-MALAT1 could inhibit RGC apoptosis in glaucoma through activation of the PI3K/Akt signaling pathway.

    Matched MeSH terms: Microscopy, Electron, Transmission
  8. Daood U, Matinlinna JP, Pichika MR, Mak KK, Nagendrababu V, Fawzy AS
    Sci Rep, 2020 07 03;10(1):10970.
    PMID: 32620785 DOI: 10.1038/s41598-020-67616-z
    To study the antimicrobial effects of quaternary ammonium silane (QAS) exposure on Streptococcus mutans and Lactobacillus acidophilus bacterial biofilms at different concentrations. Streptococcus mutans and Lactobacillus acidophilus biofilms were cultured on dentine disks, and incubated for bacterial adhesion for 3-days. Disks were treated with disinfectant (experimental QAS or control) and returned to culture for four days. Small-molecule drug discovery-suite was used to analyze QAS/Sortase-A active site. Cleavage of a synthetic fluorescent peptide substrate, was used to analyze inhibition of Sortase-A. Raman spectroscopy was performed and biofilms stained for confocal laser scanning microscopy (CLSM). Dentine disks that contained treated dual-species biofilms were examined using scanning electron microscopy (SEM). Analysis of DAPI within biofilms was performed using CLSM. Fatty acids in bacterial membranes were assessed with succinic-dehydrogenase assay along with time-kill assay. Sortase-A protein underwent conformational change due to QAS molecule during simulation, showing fluctuating alpha and beta strands. Spectroscopy revealed low carbohydrate intensities in 1% and 2% QAS. SEM images demonstrated absence of bacterial colonies after treatment. DAPI staining decreased with 1% QAS (p 
    Matched MeSH terms: Microscopy, Electron, Scanning
  9. Jaafaru MS, Nordin N, Shaari K, Rosli R, Abdull Razis AF
    PLoS One, 2018;13(5):e0196403.
    PMID: 29723199 DOI: 10.1371/journal.pone.0196403
    Reactive oxygen species are well known for induction of oxidative stress conditions through oxidation of vital biomarkers leading to cellular death via apoptosis and other process, thereby causing devastative effects on the host organs. This effect is believed to be linked with pathological alterations seen in several neurodegenerative disease conditions. Many phytochemical compounds proved to have robust antioxidant activities that deterred cells against cytotoxic stress environment, thus protect apoptotic cell death. In view of that we studied the potential of glucomoringin-isothiocyanate (GMG-ITC) or moringin to mitigate the process that lead to neurodegeneration in various ways. Neuroprotective effect of GMG-ITC was performed on retinoic acid (RA) induced differentiated neuroblastoma cells (SHSY5Y) via cell viability assay, flow cytometry analysis and fluorescence microscopy by means of acridine orange and propidium iodide double staining, to evaluate the anti-apoptotic activity and morphology conservation ability of the compound. Additionally, neurite surface integrity and ultrastructural analysis were carried out by means of scanning and transmission electron microscopy to assess the orientation of surface and internal features of the treated neuronal cells. GMG-ITC pre-treated neuron cells showed significant resistance to H2O2-induced apoptotic cell death, revealing high level of protection by the compound. Increase of intracellular oxidative stress induced by H2O2 was mitigated by GMG-ITC. Thus, pre-treatment with the compound conferred significant protection to cytoskeleton and cytoplasmic inclusion coupled with conservation of surface morphological features and general integrity of neuronal cells. Therefore, the collective findings in the presence study indicated the potentials of GMG-ITC to protect the integrity of neuron cells against induced oxidative-stress related cytotoxic processes, the hallmark of neurodegenerative diseases.
    Matched MeSH terms: Microscopy, Electron, Scanning
  10. Nazratun Nafizah AH, Budin SB, Zaryantey AH, Mariati AR, Santhana RL, Osman M, et al.
    Arab J Gastroenterol, 2017 Mar;18(1):13-20.
    PMID: 28336227 DOI: 10.1016/j.ajg.2017.02.001
    BACKGROUND AND STUDY AIMS: The complex series of deleterious events among diabetes patients leads to multiple organ failure. Therefore, a holistic approach of treatment is urgently required to prevent worsening of complications. The present investigation was carried out to study the possible protective effects of Roselle or Hibiscus sabdariffa Linn (HSL) calyxes aqueous extract, as an antidiabetic and antioxidant agent against oxidative liver injury in streptozotocin-induced diabetic rats.

    MATERIAL AND METHODS: A single dose of streptozotocin (45mg/kg body weight, iv) was used to induced diabetes in male Sprague Dawley rats which were then divided into two groups: Diabetic control (DC) and HSL-treated diabetic (DR) group. Normal rats were divided into normal control (NC), HSL-treated control (NR). Aqueous calyxes extract of HSL (100mg/kg/day, orally) was given for 28 consecutive days in the treated group. Weight, biochemical and histopathological (light and electron microscopic) parameters were compared in all groups.

    RESULTS: Supplementation of HSL significantly lowered the level of fasting blood glucose and increased plasma insulin level in DR group compared to DC group (p<0.05). Alanine aminotransaminases and aspartate aminotransferase enzymes level were found to be significantly reduced in DR compared to DC. Microscopic examination demonstrated destruction of the liver architecture, cytoplasmic vacuolation of the hepatocytes and signs of necrosis in diabetic rats. Moreover, dilatation and congestion of blood vessels with leucocytes adherence were detected. Ultrastructural study using electron microscope showed homogeneous substance accumulation in nuclear chromatin, a decrease of organelles and mitochondrial degeneration in the diabetic rats.

    CONCLUSION: Administration of HSL in diabetic rats causes significant decrease in hepatocyte destruction and prevented the changes associated with the diabetic condition. Thus, our findings provide a scientific rationale for the use of HSL as promising agent in preventing liver injury in diabetes.

    Matched MeSH terms: Microscopy, Electron
  11. Badran MM, Alomrani AH, Harisa GI, Ashour AE, Kumar A, Yassin AE
    Biomed Pharmacother, 2018 Oct;106:1461-1468.
    PMID: 30119220 DOI: 10.1016/j.biopha.2018.07.102
    In the present study, docetaxel (DTX)-loaded poly(lactic-co-glycolic acid) (PLGA) and polycaprolactone (PCL) nanoparticles were successfully prepared and coated with chitosan (CS). The prepared nanoparticles (NPs) were evaluated for their particle size, zeta potential, particle morphology, drug entrapment efficiency (EE%), and in vitro drug release profile. The anticancer activity of DTX-loaded NPs was assessed in human HT29 colon cancer cell line utilizing MTT assay. The pharmacokinetics of DTX-loaded NPs was monitored in Wistar rats in comparison to DTX solution. The prepared NPs exhibited particle sizes in the range 177.1 ± 8.2-287.6 ± 14.3 nm. CS decorated NPs exhibited a significant increase in particle size and a switch of zeta potential from negative to positive. In addition, high EE% values were obtained for CS coated PCL NPs and PLGA NPs as 67.1 and 76.2%, respectively. Moreover, lowering the rate of DTX in vitro release was achieved within 48 h by using CS coated NPs. Furthermore, a tremendous increase in DTX cytotoxicity was observed by CS-decorated PLGA NPs compared to all other NPs including DTX-free-NPs and pure DTX. The in vivo study revealed significant enhancement in DTX bioavailability from CS-decorated PLGA NPs with more than 4-fold increase in AUC compared to DTX solution. In conclusion, CS-decorated PLGA NPs are a considerable DTX-delivery carrier with magnificent antitumor efficacy.
    Matched MeSH terms: Microscopy, Electron, Scanning
  12. Sheshala R, Peh KK, Darwis Y
    Drug Dev Ind Pharm, 2009 Nov;35(11):1364-74.
    PMID: 19832637 DOI: 10.3109/03639040902939213
    AIM: The aim of this study was to prepare insulin-loaded poly(lactic acid)-polyethylene glycol microspheres that could control insulin release at least for 1 week and evaluate their in vivo performance in a streptozotocin-induced diabetic rat model.
    METHODS: The microspheres were prepared using a water-in-oil-in-water double emulsion solvent evaporation technique. Different formulation variables influencing the yield, particle size, entrapment efficiency, and in vitro release profiles were investigated. The pharmacokinetic study of optimized formulation was performed with single dose in comparison with multiple dose of Humulin 30/70 as a reference product in streptozotocin-induced diabetic rats.
    RESULTS: The optimized formulation of insulin microspheres was nonporous, smooth-surfaced, and spherical in structure under scanning electron microscope with a mean particle size of 3.07 microm and entrapment efficiency of 42.74% of the theoretical amount incorporated. The in vitro insulin release profiles was characterized by a bimodal behavior with an initial burst release because of the insulin adsorbed on the microsphere surface, followed by slower and continuous release corresponding to the insulin entrapped in polymer matrix.
    CONCLUSIONS: The optimized formulation and reference were comparable in the extent of absorption. Consequently, these microspheres can be proposed as new controlled parenteral delivery system.
    Matched MeSH terms: Microscopy, Electron, Scanning
  13. Aithal AP, Bairy LK, Seetharam RN, Rao MK
    J Cell Biochem, 2019 08;120(8):13026-13036.
    PMID: 30873677 DOI: 10.1002/jcb.28573
    BACKGROUND: To evaluate the antimutagenic potential of combination treatment of human bone marrow-derived mesenchymal stromal cells (BM-MSCs) and silymarin and its effect on hepatocyte growth factor levels in CCl4 induced hepatotoxicity in Wistar rats.

    METHODS: Hepatotoxicity was induced in adult female Wistar rats using carbon tetrachloride (CCl4 ). Thirty-six rats were randomly divided into six groups with six rats in each group: Group 1 (normal control group), Group 2 (received only CCl 4 ), Group 3 (CCl 4 +low dose BM-MSCs), Group 4 (CCl 4 +high dose BM-MSCs), Group 5 (CCl 4  + silymarin), Group 6 (CCl 4 +silymarin+high dose BM-MSCs). Thirty days after the treatment, blood samples were collected for hepatocyte growth factor estimation. The rats were then killed, bone marrow was extracted for chromosomal aberration assay. Liver tissue was processed for evaluating the DNA fragmentation assay, histopathology, and scanning electron microscopy study.

    RESULTS: Combination treatment of silymarin and high dose BM-MSCs significantly (P electron microscopy study.

    CONCLUSION: Results indicate that the treatment of BM-MSCs in combination with silymarin had a better hepatoprotective and antimutagenic effect and represents a novel strategy for the treatment of hepatotoxicity.

    Matched MeSH terms: Microscopy, Electron, Scanning
  14. Yong CY, Yeap SK, Goh ZH, Ho KL, Omar AR, Tan WS
    Appl Environ Microbiol, 2015 Feb;81(3):882-9.
    PMID: 25416760 DOI: 10.1128/AEM.03695-14
    Hepatitis B virus (HBV) is a deadly pathogen that has killed countless people worldwide. Saccharomyces cerevisiae-derived HBV vaccines based upon hepatitis B surface antigen (HBsAg) is highly effective. However, the emergence of vaccine escape mutants due to mutations on the HBsAg and polymerase genes has produced a continuous need for the development of new HBV vaccines. In this study, the "a" determinant within HBsAg was displayed on the recombinant capsid protein of Macrobrachium rosenbergii nodavirus (MrNV), which can be purified easily in a single step through immobilized metal affinity chromatography (IMAC). The purified protein self-assembled into virus-like particles (VLPs) when observed under a transmission electron microscope (TEM). Immunization of BALB/c mice with this chimeric protein induced specific antibodies against the "a" determinant. In addition, it induced significantly more natural killer and cytotoxic T cells, as well as an increase in interferon gamma (IFN-γ) secretion, which are vital for virus clearance. Collectively, these findings demonstrated that the MrNV capsid protein is a potential carrier for the HBV "a" determinant, which can be further extended to display other foreign epitopes. This paper is the first to report the application of MrNV VLPs as a novel platform to display foreign epitopes.
    Matched MeSH terms: Microscopy, Electron, Transmission
  15. Chao CY, Mani MP, Jaganathan SK
    PLoS One, 2018;13(10):e0205699.
    PMID: 30372449 DOI: 10.1371/journal.pone.0205699
    Essential oils play an important role in reducing the pain and inflammation caused by bone fracture.In this study, a scaffold was electrospun based on polyurethane (PU), grape seed oil, honey and propolis for bone tissue-engineering applications. The fiber diameter of the electrospun PU/grape seed oil scaffold and PU/grape seed oil/honey/propolis scaffold were observed to be reduced compared to the pristine PU control. FTIR analysis revealed the existence of grape seed oil, honey and propolis in PU identified by CH band peak shift and also hydrogen bond formation. The contact angle of PU/grape seed oil scaffold was found to increase owing to hydrophobic nature and the contact angle for the PU/grape seed/honey oil/propolis scaffold were decreased because of hydrophilic nature. Further, the prepared PU/grape seed oil and PU/grape seed oil/honey/propolis scaffold showed enhanced thermal stability and reduction in surface roughness than the control as revealed in thermogravimetric analysis (TGA) and atomic force microscopy (AFM) analysis. Further, the developed nanocomposite scaffold displayed delayed blood clotting time than the pristine PU in the activated prothrombin time (APTT) and partial thromboplastin time (PT) assay. The hemolytic assay and cytocompatibility studies revealed that the electrospun PU/grape seed oil and PU/grape seed oil/honey/propolis scaffold possess non-toxic behaviour to red blood cells (RBC) and human fibroblast cells (HDF) cells indicating better blood compatibility and cell viability rates. Hence, the newly developed electrospun nanofibrous composite scaffold with desirable characteristics might be used as an alternative candidate for bone tissue engineering applications.
    Matched MeSH terms: Microscopy, Electron, Scanning
  16. Chua PK, Corkill JE, Hooi PS, Cheng SC, Winstanley C, Hart CA
    Emerg Infect Dis, 2005 Feb;11(2):271-7.
    PMID: 15752446
    An obligate intracellular bacterium was isolated from urine samples from 7 (3.5%) of 202 fruit bats (Eonycteris spelaea) in peninsular Malaysia. The bacterium produced large membrane-bound inclusions in human, simian, and rodent cell lines, including epithelial, fibroblastlike, and lymphoid cells. Thin-section electron microscopy showed reticulate bodies dividing by binary fission and elementary bodies in the inclusions; mitochondria surrounded the inclusions. The inclusions were positive for periodic acid-Schiff stain but could not be stained by fluorescein-labeled anti-Chlamydia trachomatis major outer membrane protein monoclonal antibody. The bacterium was resistant to penicillin and streptomycin (MICs > 256 mg/L) but susceptible to tetracycline (MIC = 0.25 mg/L) and chloramphenicol (MIC = 0.5 mg/L). Sequence analysis of the 16SrRNA gene indicated that it was most closely related to 2 isolates of Waddlia chondrophila (94% and 96% identity). The 16S and 23S rRNA gene signatures were only 91% identical. We propose this novel bacterium be called W. malaysiensis.
    Matched MeSH terms: Microscopy, Electron
  17. Gnanaraj C, Shah MD, Song TT, Iqbal M
    Biomed Pharmacother, 2017 Aug;92:1010-1022.
    PMID: 28609838 DOI: 10.1016/j.biopha.2017.06.014
    Plants have been consumed in medicinal practices for centuries. Lygodium microphyllum (Cav.) R.Br. (Lygodiaceae), also known as Old World Climbing Fern, is a medicinal plant used by local communities in Sabah for skin and dysentery ailments. This study aims to test aqueous extract of L. microphyllum leaves for hepatoprotective and immunosuppressive activity in rats. Animal studies were carried out to evaluate hepatoprotection of aqueous extract of L. microphyllum at different doses (200, 400 and 600mg/kg b.w.) against carbon tetrachloride (CCl4)-mediated liver injury and histopathological alterations. Total phenolic content in aqueous extract of L. microphyllum leaves was 206.38±9.62mg gallic acid equivalent/g. The inhibitory concentration (IC50) for free radical scavenging activity of L. microphyllum was reached at a concentration of 65μg/ml.L. microphyllum was able to prevent the increase in levels of serum alanine aminotransferase, serum aspartate aminotransferase and hepatic malondialdehyde formation in a dose-dependent manner. Immunohistochemical results evidenced the suppression of oxidative stress markers (4-hydroxynonenal, 8-hydroxydeoxyguanosine) and pro-inflammatory cytokines (Tumor Necrosis Factor-α, Interleukin-6, Prostaglandin E2). Histopathological and hepatocyte ultrastructural alterations showed protective effects by L. microphyllum against CCl4-mediated oxidative stress. Hepatoprotective mechanism of L. microphyllum can be attributed to its antioxidative effects through protection of ultrastructural organelles.
    Matched MeSH terms: Microscopy, Electron, Transmission
  18. Smn Mydin RB, Sreekantan S, Hazan R, Farid Wajidi MF, Mat I
    Oxid Med Cell Longev, 2017;2017:3708048.
    PMID: 28337249 DOI: 10.1155/2017/3708048
    Cell growth and proliferative activities on titania nanotube arrays (TNA) have raised alerts on genotoxicity risk. Present toxicogenomic approach focused on epithelial HT29 cells with TNA surface. Fledgling cell-TNA interaction has triggered G0/G1 cell cycle arrests and initiates DNA damage surveillance checkpoint, which possibly indicated the cellular stress stimuli. A profound gene regulation was observed to be involved in cellular growth and survival signals such as p53 and AKT expressions. Interestingly, the activation of redox regulator pathways (antioxidant defense) was observed through the cascade interactions of GADD45, MYC, CHECK1, and ATR genes. These mechanisms furnish to protect DNA during cellular division from an oxidative challenge, set in motion with XRRC5 and RAD50 genes for DNA damage and repair activities. The cell fate decision on TNA-nanoenvironment has been reported to possibly regulate proliferative activities via expression of p27 and BCL2 tumor suppressor proteins, cogent with SKP2 and BCL2 oncogenic proteins suppression. Findings suggested that epithelial HT29 cells on the surface of TNA may have a positive regulation via cell-homeostasis mechanisms: a careful circadian orchestration between cell proliferation, survival, and death. This nanomolecular knowledge could be beneficial for advanced medical applications such as in nanomedicine and nanotherapeutics.
    Matched MeSH terms: Microscopy, Electron, Scanning
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