Vitro

Source: www.ncbi.nlm.nih.gov --- 9 days ago
Related Articles In Vitro and in vivo modulation of the equine immune response by parapoxvirus ovis. Equine Vet J. 2008 Jul;40(5):468-72 Authors: Horohov DW, Breathnach CC, Sturgill TL, Rashid C, Stiltner JL, Strong D, Nieman N, Holland RE REASON FOR PERFORMING STUDY: While immune modulators are used routinely in equine medicine, their mechanism of action is not always known. OBJECTIVES: To determine the effect of a commercial preparation of inactivated parapoxvirus ovis (Orf virus; PPVO) on cytokine gene expression by equine peripheral blood mononuclear cells (PBMC) both in Vitro and in vivo. METHODS: PBMC were prepared from 6 mixed-breed yearlings and cultured in Vitro with PPVO with or without Concanavalin A (Con A) for 24 h. Effects on the expression of IFNalpha, IFNbeta IFNgamma, TNFalpha and IL-18 were analysed by real time quantitative PCR (RT-PCR). In addition, 12 yearling horses were treated with PPVO and whole blood RNA samples were prepared at regular intervals to assess effects on in vivo cytokine gene expression. Six of those yearlings were later treated with saline and served as treatment controls. Nine additional yearlings were injected intradermally with a single dose and their injection sites biopsied at 24 and 48 h for cytokine expression. RESULTS: In Vitro culture of PBMC with PPVO led to a significant increase in IFNalpha and IFNbeta gene expression compared to mock-stimulated cultures. In addition, expression of IF ...

Source: www.ncbi.nlm.nih.gov --- 12 hours ago
Elevated synaptic activity preconditions neurons against an in Vitro model of Ischemia. J Biol Chem. 2008 Oct 9; Authors: Tauskela JS, Fang H, Hewitt M, Brunette E, Ahuja T, Thiverge JP, Comas T, Mealing GA Tolerance to otherwise lethal cerebral ischemia in vivo or to oxygen-glucose deprivation (OGD) in Vitro can be induced by prior transient exposure to NMDA: preconditioning in this manner activates extrasynaptic and synaptic NMDA receptors and can require bringing neurons to the 'brink of death'. We considered if this stressful requirement could be minimized by the stimulation of primarily synaptic NMDA receptors. Subjecting cultured cortical neurons to prolonged elevations in electrical activity induced tolerance to OGD. Specifically, exposing cultures to a K+-channel blocker, 4-aminopyridine (20-2500 microM), and a GABAA receptor antagonist, bicuculline (50 microM; 4-AP/bic), for 1-2 days resulted in potent tolerance to normally lethal OGD applied up to 3 days later. Preconditioning induced phosphorylation of ERK1/2 and CREB which, along with Ca2+ spiking and OGD tolerance, was eliminated by tetrodotoxin. Antagonists of NMDA receptors or L-type voltage-gated Ca2+ channels (L-VGCCs) applied during preconditioning decreased Ca2+ spiking, phosphorylation of ERK1/2 and CREB, and OGD tolerance more effectively when combined, particularly at the lowest 4-AP concentration. Inhibiting ERK1/2 or Ca2+/calmodulin-dependent protein kinases ( ...

Source: www.ncbi.nlm.nih.gov --- 10 hours ago
The compatibility of hepatocytes with chemically modified porous silicon with reference to in Vitro biosensors. Biomaterials. 2008 Oct 7; Authors: Alvarez SD, Derfus AM, Schwartz MP, Bhatia SN, Sailor MJ Porous Si is a nanostructured material that is of interest for molecular and cell-based biosensing, drug delivery, and tissue engineering applications. Surface chemistry is an important factor determining the stability of porous Si in aqueous media, its affinity for various biomolecular species, and its compatibility with tissues. In this study, the attachment and viability of a primary cell type to porous Si samples containing various surface chemistries is reported, and the ability of the porous Si films to retain their optical reflectivity properties relevant to molecular biosensing is assessed. Four chemical species grafted to the porous Si surface are studied: silicon oxide (via ozone oxidation), dodecyl (via hydrosilylation with dodecene), undecanoic acid (via hydrosilylation with undecylenic acid), and oligo(ethylene) glycol (via hydrosilylation with undecylenic acid followed by an oligo(ethylene) glycol coupling reaction). Fourier Transform Infrared (FTIR) spectroscopy and contact angle measurements are used to characterize the surface. Adhesion and short-term viability of primary rat hepatocytes on these surfaces, with and without pre-adsorption of collagen type I, are assessed using vital dyes (calcein-AM and ethidium homod ...

Source: www.ncbi.nlm.nih.gov --- 7 days ago
Related Articles In Vitro evaluation of the dissolution behaviour of itraconazole in bio-relevant media. Int J Pharm. 2008 Sep 11; Authors: Ghazal HS, Dyas AM, Ford JL, Hutcheon GA Drugs in the gastrointestinal tract are exposed to a medium of partially digested food, comprising mixtures of fat, protein and carbohydrate. The dissolution behaviour of itraconazole was evaluated in bio-relevant media which were developed to take this into account. Media containing milk with different fat contents, protein (albumin, casein, gluten and gelatin), carbohydrates (glucose, lactose and starch) and amino acids (lysine, glycine, alanine and aspartic acid) to mimic a digested meal and bile components (sodium taurocholate and lecithin) to represent a key endogenous digestive material were investigated. The effect of medium composition on the intrinsic dissolution rate of itraconazole was evaluated as this drug has extremely poor solubility and its bioavailability is affected by food. Dissolution tests were carried out in simple compendial media based on dilute solutions of hydrochloric acid or neutral solutions of phosphate buffer and in more complex media containing the dietary components. The data obtained showed that most of the dietary components enhanced the solubility compared to simulated gastric fluid (SGF) but to differing extents. The greatest increase in dissolution was observed with the addition of milk and albumin although an increase ...

Source: www.ncbi.nlm.nih.gov --- 3 days ago
Related Articles Highly crosslinked vs conventional polyethylene particles--an in Vitro comparison of biologic activities. J Arthroplasty. 2008 Aug;23(5):721-31 Authors: Illgen RL, Forsythe TM, Pike JW, Laurent MP, Blanchard CR Highly cross-linked polyethylenes (HXPEs) have been introduced to reduce wear after hip arthroplasty. The improved wear characteristics of HXPEs are well documented, but the relative biologic activity of HXPE and conventional polyethylene (CPE) particles remains unclear. Longevity (Zimmer, Warsaw, Ind; HXPE) and GUR 1050 (Zimmer; CPE) particles were isolated and characterized from a hip simulator and their in Vitro inflammatory responses (tissue necrosis factor *, interleukin 1*, and vascular endothelial growth factor levels) were compared using macrophages. The average diameter of Longevity particles (0.111 microm) was smaller than CPE particles (0.196 microm), and both were predominantly round (granular appearance). The inflammatory response to HXPE and CPE was concentration-dependent. No statistically significant differences were noted at low (0.1 surface area ratio [SAR]) and intermediate (0.75 SAR) doses. At the highest dose tested (2.5 SAR), HXPE was significantly more inflammatory than CPE based on relative tissue necrosis factor alpha and vascular endothelial growth factor secretion levels. Further study is needed to determine if similar findings would be noted in vivo over a broad concentration range. ...

Source: www.ncbi.nlm.nih.gov --- 3 days ago
Related Articles Neuroprotective effects of berberine on stroke models in Vitro and in vivo. Neurosci Lett. 2008 Sep 30; Authors: Zhou XQ, Zeng XN, Kong H, Sun XL Berberine is an alkaloid derived from herb medicine Coptidis Rhizom. Although there are increasing evidences that berberine exhibits neuroprotective effects against ischemic brain damage, little is known about the mechanism. In this study, we investigated the effect of berberine on ischemic injury in a middle cerebral artery occlusion (MCAO) model. We found that berberine improved neurological outcome and reduced ischemia-reperfusion (I/R)-induced cerebral infarction 48h after MCAO. The protective effect of berberine was confirmed in in Vitro study. Berberine protected PC12 cell against oxygen-glucose deprivation (OGD)-induced injury. The results showed that berberine inhibited reactive oxygen species (ROS) generation, and subsequent release of pro-apoptotic factor cytochrome c and apoptosis-inducing factors (AIFs) evoked by OGD. Findings of this study suggest that berberine protects against ischemic brain injury by decreasing the intracellular ROS level and subsequently inhibiting mitochondrial apoptotic pathway. PMID: 18838103 [PubMed - as supplied by publisher] ...

Source: www.ncbi.nlm.nih.gov --- 10 days ago
Related Articles In Vitro reactivation of trichlorfon-inhibited butyrylcholinesterase using HI-6, obidoxime, pralidoxime and K048. J Enzyme Inhib Med Chem. 2008 Sep 29;:1 Authors: Pohanka M, Jun D, Kuca K Trichlorfon is a specific inhibitor of cholinesterases. It was typically used as an insecticide; however, trichlorfon was described as useful for symptomatic treatment of Alzheimer's disease some years ago. The presented study is aimed at reactivation of trichlorfon-inhibited butyrylcholinesterase since this enzyme play an important role in Alzheimer's disease as deputy for acetylcholinesterase and furthermore it could be applied as a scavenger in case of overdosing. We used in Vitro reactivation test for considering only reactivation efficacy of butyrylcholinesterase that is inhibited by trichlorfon and not reactivation of butyrylcholinesterase inhibited by trichlorfon metabolic products. Four reactivators were used: HI-6, pralidoxime, obidoxime, and K048. Although all of the reactivators seem to be effective at 1 mM concentration, a lower concentration was not able ensure sufficient reactivation. There was also an observed lowering of reactivation efficacy when butyrylcholinesterase was exposed to trichlorfon for a longer time interval. PMID: 18825528 [PubMed - as supplied by publisher] ...

Source: www.ncbi.nlm.nih.gov --- 2 days ago
Related Articles Pharmacological profiling of neuropeptides on rabbit vaginal wall and vaginal artery smooth muscle in Vitro. Br J Pharmacol. 2008 Sep;155(2):236-43 Authors: Aughton KL, Hamilton-Smith K, Gupta J, Morton JS, Wayman CP, Jackson VM BACKGROUND AND PURPOSE: Hypothalamic neuropeptides centrally modulate sexual arousal. However, the role of neuropeptides in peripheral arousal has been ignored. Vascular and non-vascular smooth muscle relaxation in the vagina is important for female sexual arousal. To date, in Vitro studies have focused on vaginal strips with no studies on vaginal arteries. The aim of this study was to compare the effects of sexual hypothalamic neuropeptides on rabbit vaginal wall strips and arteries. EXPERIMENTAL APPROACH: Tissue bath and wire myography techniques were used to measure isometric tension from strips and arteries, respectively. KEY RESULTS:Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) relaxed both preparations, effects that were only antagonized by the VIP/PACAP antagonist VIP6-28 (10 nM) and the PAC(1) antagonist PACAP 6-38 (1 microM). The melanocortin agonist alpha-melanocortin-stimulating hormone (1 microM), but not bremelanotide (1 microM), also relaxed both preparations. Oxytocin and vasopressin contracted vaginal preparations, which could be antagonized by the V(1A) antagonist SR 49059. Neuropeptide Y (NPY) and the NPY Y(1) agonist Leu(3 ...

Source: www.ncbi.nlm.nih.gov --- 1 day ago
Related Articles Differentiation of human monocytes in Vitro following exposure to Canova in the absence of cytokines. Ultrastruct Pathol. 2008 Jul-Aug;32(4):147-52 Authors: Smit E, Pretorius E, Anderson R, Oommen J, Potjo M Canova is an immunomodulatory, homeopathic preparation that has been shown to activate macrophages in Vitro and in vivo, with resultant enhanced spreading of the cells and formation of microvillus extensions from the cell body. Since monocytes are the precursor cells of macrophages and dendritic cells, the objective of the current study was to investigate the effects of Canova on the differentiation of human blood monocytes in Vitro. Monocytes were isolated, grown in culture, and exposed to 10 and 20% Canova without the addition of cytokines. After 48 h, monocytes were prepared for analysis by scanning electron microscopy, while cells kept in culture for 7 days and exposed to Canova on days 1, 3, and 4 were analyzed by flow cytometry for alterations in the levels of expression of CD1a, CD11c, CD14, CD80, CD83, CD86, and HLA-DR. SEM revealed that monocytes exposed to 10% Canova had a morphological appearance similar to that of macrophages. Various cytoplasmic projections were observed with pseudopodia formation. Flow cytometric analysis after exposure of monocytes to 10 and 20% Canova indicated high cell viability and upregulation of CD80, compatible with differentiation into either macrophages or dendritic cells. ...

Source: www.ncbi.nlm.nih.gov --- 9 days ago
Related Articles [Expression of imprinted Igf2 and Peg1/Mest genes in postimplantation parthenogenetic mouse embryos treated with transforming growth factor alpha in Vitro] Genetika. 2008 Aug;44(8):1148-52 Authors: The effect of transforming growth factor alpha (TGFt) on the expression of imprinted Igf2 and Peg1/Mest genes was studied in diploid parthenogenetic embryos (PEs) of (CBA x C57BL/6)F1 mice during the postimplantation period of embryogenesis. The PEs were treated with TGFalpha in Vitro at the morula stage and, after they developed to the blastocyst stage, were implanted into the uterus of false-pregnant females. On the tenth day of pregnancy, the PEs were explanted for subsequent in Vitro culturing for 24 or 48 h. The expression of the imprinted Igf2 and Peg1/Mest genes was studied by means of whole mount in situ hybridization using digoxigenin-labeled antisense RNAs. The expression of the imprinted Igf2 and Peg1/Mest genes was studied in embryos on the tenth day of in utero development before culturing and after 24 and 48 h of culturing in Vitro. The expression of Igf2 before culturing was detected only in the brain of 60% of PEs on the tents day of pregnancy (the 21-to 25-somite stages); while the Peg1/Mest expression was not detected at all. In control (not treated with TGFalpha) PEs, neither gene was expressed at the same 21- to 25-somite stages. After 24 h of culturing, the Igf2 expression was detected in the brain of 71 ...

Source: www.ncbi.nlm.nih.gov --- 9 hours ago
Related Articles [Curcumin inhibits the expression of vascular endothelial growth factor and androgen-independent prostate cancer cell line PC-3 in Vitro] Zhonghua Nan Ke Xue. 2008 Feb;14(2):116-21 Authors: Deng G, Yu JH, Ye ZQ, Hu ZQ OBJECTIVE: To study the effects of curcumin on the expression of the vascular endothelial growth factor (VEGF) and androgen-independent prostate cancer cell line PC-3, and to explore its anticarcinogenic mechanism. METHODS: PC-3 cells were treated with curcumin at the concentration of 0, 6.25, 12.5, 25 and 50 micromol/L respectively. Then the cell activity was assayed by dyed rate of Typan blue and MTT at 12, 24, 36, 48, 72 and 96 hours, the cell cycle and morphological changes observed by flow cytometry (FCM) and electronic microscopy at 24 hours, the VEGF mRNA expression measured by semi-quantitative RT-PCR, and the secreting protein levels of VEGF in the supernatants determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: The growth of PC-3 cells was suppressed obviously by curcumin in a dose- and time-dependent manner in Vitro. There were significant differences in inhibition rate among different concentration and time groups (P < 0.01). Furthermore, curcumin arrested the cell cycle of PC-3 cells in the G2/M phase in a dose-dependent manner (P < 0.01). The percentages of apoptotic cells were significantly higher in different concentration groups than in the controls (P < 0.01). Apoptosis-a ...

Source: www.ncbi.nlm.nih.gov --- 8 days ago
Related Articles Design, synthesis and in Vitro microbiological evaluation of 6,6-dimethyl-7,9-diaryl-1,2,4,8-tetraazaspiro[4.5]decan-3-thiones - A new series of 'tailor-made' compounds. J Enzyme Inhib Med Chem. 2008 Oct 1;:1 Authors: Gopalakrishnan M, Thanusu J, Kanagarajan V, Govindaraju R Some novel 'tailor-made' compounds, 6,6-dimethyl-7,9-diaryl-1,2,4,8-tetraazaspiro[4.5]decan-3-thiones 23-27 have been studied for their in Vitro antibacterial activity against Staphylococcus aureus, beta-Heamolytic streptococcus, Vibreo cholerae, Salmonella typhii, Shigella felxneri, Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa and anti-fungal activity against Aspergillus flavus, Mucor, Rhizopus and Microsporum gypsuem. Compounds 24 and 25 exerted potent antibacterial activity against S. aureus, beta-H. streptococcus, E. coli and P. aeruginosa whereas all compounds 23-27 exerted strong in Vitro antifungal activity against A. flavus, Mucor and Rhizopus. PMID: 18830884 [PubMed - as supplied by publisher] ...

Source: www.ncbi.nlm.nih.gov --- 3 days ago
Related Articles Synthesis, In Vitro, and In Silico Evaluation of Organometallic Technetium and Rhenium Thymidine Complexes with Retained Substrate Activity toward Human Thymidine Kinase Type 1. J Med Chem. 2008 Oct 7; Authors: Desbouis D, Struthers H, Spiwok V, Küster T, Schibli R Human cytosolic thymidine kinase (hTK1) has proven to be a suitable target for noninvasive imaging of cancer cell proliferation using radiolabeled substrates such as [ (18)F]fluorothymidine ([ (18)F]FLT). However, a thymidine tracer useful for single photon emission tomography (SPECT) based on the inexpensive radionuclide technetium-99m would be of significant interest. In this work, a series of thymidine derivatives labeled with the organometallic [M(CO) 3] (+) core (M = (99m)Tc, Re) were synthesized. Neutral, cationic, and anionic complexes were readily formed in aqueous media, and all were substrates of recombinant hTK1 when incubated with ATP. The neutral complexes were phosphorylated to a greater extent than the charged complexes. The extent of phosphorylation was further improved by increasing the spacer length separating thymidine and the organometallic core. A molecular dynamics simulation study performed with a modified hTK1 structure supported the experimental findings. In Vitro cell internalization experiments performed in a human neuroblastoma cell line (SKNMC) showed low uptake of the charged complexes but significant uptake for the neutral, l ...

Source: www.ncbi.nlm.nih.gov --- 2 days ago
Related Articles The Effects of Endomorphins on Striatal [(3)H]Gaba Release Induced by Electrical Stimulation: An In Vitro Superfusion Study in Rats. Neurochem Res. 2008 Oct 8; Authors: Bagosi Z, Jászberényi M, Telegdy G The endomorphins (EM1 and EM2) are selective endogenous ligands for mu-opioid receptors (MOR1 and MOR2) with neurotransmitter and neuromodulator roles in mammals. In the present study we investigated the potential actions of EMs on striatal GABA release and the implication of different MORs in these processes. Rat striatal slices were preincubated with tritium-labelled GABA ([(3)H]GABA), pretreated with selective MOR1 and MOR2 antagonist beta-funaltrexamine and selective MOR1 antagonist naloxonazine and then superfused with the selective MOR agonists, EM1 and EM2. EM1 significantly decreased the striatal [(3)H]GABA release induced by electrical stimulation. Beta-funaltrexamine antagonized the inhibitory action of EM1, but naloxonazine did not affect it considerably. EM2 was ineffective, even in case of specific enzyme inhibitor diprotin A pretreatment. The results demonstrate that EM1 decreases GABA release in the basal ganglia through MOR2, while EM2 does not influence it. PMID: 18841469 [PubMed - as supplied by publisher] ...

Source: www.ncbi.nlm.nih.gov --- 8 days ago
Related Articles In Vitro production of tumor necrosis factor-alpha by human monocytes stimulated with lipopolysaccharide is positively correlated with increased blood monocytes after exposure to a swine barn. J Toxicol Environ Health A. 2008;71(21):1401-6 Authors: Willson PJ, Khozani TT, Juurlink BH, Senthilselvan A, Rennie DC, Gerdts V, Gawaziuk J, Schneberger D, Burch LH, Dosman JA Recently there has been interest in the air quality in and around intensive livestock production facilities, such as modern swine production barns, where agricultural workers and surrounding residents may be exposed to elevated levels of organic dusts. The health effects of these exposures are not completely understood. The study that is reported here is a component of a larger investigation of the relationships among the acute effects of high-concentration endotoxin exposure (swine barn dust), polymorphisms in the TLR4 gene, and respiratory outcomes following exposure to swine confinement buildings. The relationships among a mediator of acute lung inflammation, tumor necrosis factor alpha (TNF-alpha), and clinical responses to acute swine barn exposure were characterized. Analysis of the results showed that in Vitro stimulation of human monocytes with as little as 1 ng/ml of lipopolysaccharide (LPS) produced a significant increase in the monocytes that produced TNF-alpha. Although the proportion of TNF-alpha-positive monocytes after in Vitro stimulation ...

Source: www.ncbi.nlm.nih.gov --- 3 days ago
Related Articles Differing in Vitro biology of equine, ovine, porcine and human articular chondrocytes derived from the knee joint: an immunomorphological study. Histochem Cell Biol. 2008 Oct 7; Authors: Schulze-Tanzil G, Müller RD, Kohl B, Schneider N, Ertel W, Ipaktchi K, Hünigen H, Gemeinhardt O, Stark R, John T For lack of sufficient human cartilage donors, chondrocytes isolated from various animal species are used for cartilage tissue engineering. The present study was undertaken to compare key features of cultured large animal and human articular chondrocytes of the knee joint. Primary chondrocytes were isolated from human, porcine, ovine and equine full thickness knee joint cartilage and investigated flow cytometrically for their proliferation rate. Synthesis of extracellular matrix proteins collagen type II, cartilage proteoglycans, collagen type I, fibronectin and cytoskeletal organization were studied in freshly isolated or passaged chondrocytes using immunohistochemistry and western blotting. Chondrocytes morphology, proliferation, extracellular matrix synthesis and cytoskeleton assembly differed substantially between these species. Proliferation was higher in animal derived compared with human chondrocytes. All chondrocytes expressed a cartilage-specific extracellular matrix. However, after monolayer expansion, cartilage proteoglycan expression was barely detectable in equine chondrocytes whereby fibronectin and collagen ty ...

Source: www.ncbi.nlm.nih.gov --- 9 days ago
Related Articles Constitutive activation of PI3-kinase signaling pathway downregulates TLR4-mediated TNF-alpha release in alveolar macrophages from asymptomatic HIV+ persons in Vitro. J Biol Chem. 2008 Sep 30; Authors: Tachado SD, Li X, Swan K, Patel N, Koziel H Alveolar macrophages (AM) represent critical effector cells of innate immunity to infectious challenge in the lungs, and recognize bacterial pathogens through pattern recognition receptors such as Toll-like receptors (TLRs). Our prior work showed reduced TLR4-mediated TNF-a release in HIV+ macrophages, attributed in part to constitutive induction of cellular phosphatase MKP-1. PI3K may also regulate TLR-mediated cytokine release, but whether HIV infection influences PI3K signaling pathway and alters TLR4-mediated macrophage response has not been investigated. In the current study, surface TLR4 expression were similar but TLR4 activation (lipid A, 10 microg/ml) resulted in lower TNF-a release by HIV+ human macrophages compared to healthy cells, consistent with prior investigations. Pharmacological inhibition of PI3K (LY294002) normalized TNF-a release in HIV+ macrophages and augments ERK1/2 MAP kinase phosphorylation in response to lipid A. Importantly, HIV+ macrophages demonstrated increased constitutive PIP3 formation, increased phosphorylation of downstream signaling molecules Akt and GSK-3ss at Ser9, and reduced PTEN protein expression. As a functional assessment of GSK-3ss ...

Source: www.ncbi.nlm.nih.gov --- 10 days ago
Related Articles Role of p53 codon 72 arginine allele in cell survival in Vitro and in the clinical outcome of patients with advanced breast cancer. Tumour Biol. 2008;29(3):145-51 Authors: Vannini I, Zoli W, Tesei A, Rosetti M, Sansone P, Storci G, Passardi A, Massa I, Ricci M, Gusolfino D, Fabbri F, Ulivi P, Brigliadori G, Amadori D, Bonafe M BACKGROUND: The p53 codon 72 polymorphism, which results in either an arginine or proline residue, plays a different role in Vitro and in vivo in cell survival and drug resistance. We verified, in Vitro, the impact of the arginine allele on cell survival under normoxia and hypoxia, and investigated in vivo the role of p53 codon 72 arginine homozygosity in the clinical outcome of advanced breast cancer patients. METHODS: Tumors at advanced stages grow in vivo in a hypoxic environment, and we mimicked such conditions in Vitro using p53 null breast cancer cells transfected with either the arginine or proline allele. We also analyzed in vivo the p53 codon 72 genotype status of advanced breast cancer patients. RESULTS: In Vitro transfection of the arginine allele induced higher cell death under normoxia, whereas cell death was greater in proline-transfected cells under hypoxia. The arginine allele upregulated BCRP-I, a hypoxia response gene, which increases drug resistance. Metastatic breast cancer patients homozygous for arginine had a significantly shorter time to progression and overall survival th ...

Source: www.ncbi.nlm.nih.gov --- 10 hours ago
In Vitro cytotoxicity of polyphosphoester as a novel injectable alveolar replacement material. J Huazhong Univ Sci Technolog Med Sci. 2008 Oct;28(5):604-7 Authors: Zhang Z, Mao J, Feng X, Xiao J, Qiu J The aim of this study was to investigate the in Vitro cytotoxicity of polyphosphoester polymer used as a novel injectable alveolar bone substitutes for controlled delivery of tetracycline. Cell culture medium was exposed to the polymer (0.01-10 mg/mL) for 24 h. The L-929 mouse fibroblasts were then exposed to the treated cell culture medium for 24 h. Finally, cell viability and growth were assessed by using MTT assay and Alamar Blue assay. No significant cytotoxicity of the polyphosphoester against L-929 mouse fibroblasts was observed at a concentration up to 10 mg/mL (P>0.05). The two evaluation methods showed no significant differences (P>0.05). This study suggests that polyphosphoester does not demonstrate any significant toxic effects to cells in Vitro and has the potential to be used both as a medical device and as scaffolds in tissue engineering applications. PMID: 18846349 [PubMed - in process] ...

Source: www.ncbi.nlm.nih.gov --- 3 days ago
Related Articles [Leptin induced apoptosis in rat adipose-derived stem cells cultured in Vitro] Sheng Wu Gong Cheng Xue Bao. 2008 Jul;24(7):1216-20 Authors: Jiang Y, Qiao H, Liu M, Li Q, Sun Y, Zhang J To determine the direct effect of leptin on adipose tissue apoptosis in Vitro using rat adipose-derived stem cells (ADSCs), we isolated the ADSCs of rat epididymis adipose tissue by collagenase digestion, filtration, and subsequent centrifugation. Cell cultures with or without leptin (10(-9) mol/L, 10(-8) mol/L, 10(-7) mol/L and 10(-6) mol/L) were incubated for different time. We examined the cell surface phenotype by immunofluorescence and detected the apoptosis morphological changes of ADSCs by laser scanning confocal microscope (LCSM). The number of apoptotic cells was determined by flow cytometry assay after annexin V binding and PI staining. Caspase-3 activity was measured by spectrofluorometry. The present study demonstrates that leptin treatment causes a marked increase in adipose-derived stem cell apoptosis. With the LCSM, after being treated with leptin, ADSCs showed the typical characteristic of apoptosis. Leptin in used concentrations (0 mol/L, 10(-8) mol/L, 10(-7) mol/L, 10(-6) mol/L) caused a marked increase in cell apoptosis after 48 h incubation time (for 2.50% +/- 0.72%, 6.78% +/- 1.99%, 11.99% +/- 1.58% and 17.93% +/- 4.82%, respectively, P < 0.05). Caspase-3 activity increased and reached a maximal level after 48 h in ...