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H Post Injection (h + post_injection)
Selected AbstractsTransgenerational marking of marine fish larvae: stable-isotope retention, physiological effects and health issuesJOURNAL OF FISH BIOLOGY, Issue 4 2009D. H. Williamson This study examined the toxicological and physiological responses of a commercially important coral-reef grouper, Plectropomus leopardus (Serranidae), to injection of enriched stable-isotope barium chloride (BaCl2) solution. Thirty adult P. leopardus were subject to one of two 138BaCl2 injection treatment groups (corresponding to dosage rates of 2 and 4 mg 138Ba kg,1 body mass), and a control group in which fish were injected with 0·9% sodium chloride (NaCl) solution. Fish from each group were sampled at post-injection intervals of 48 h and 1, 3, 5 and 8 weeks, at which time blood and tissue samples were removed from each fish. Residual concentrations of Ba and 138Ba:137Ba ratios were measured in muscle, gonad, liver and bone tissues of each experimental fish. Elevated Ba concentrations were detected in all treatment fish tissue samples within 48 h post injection. Residual Ba concentrations decreased throughout the remainder of the 8 week experimental period in all tissues except bone. The BaCl2 injection had no significant effects on measured whole blood variables or on the plasma concentrations of steroid hormones. Enriched Ba stable isotopes can therefore be used at low dosages to mark larvae of commercially important marine fishes, without adverse effects on the health of the fishes or on humans who may consume them. [source] Enhanced hippocampal F2 -isoprostane formation following kainate-induced seizuresJOURNAL OF NEUROCHEMISTRY, Issue 5 2001Manisha Patel We attempted to obtain evidence for the occurrence of oxidant injury following seizure activity by measuring hippocampal F2 -isoprostanes (F2 -IsoPs), a reliable marker of free radical-induced lipid peroxidation. Formation of F2- IsoPs esterified in hippocampal phospholipids was correlated with hippocampal neuronal loss and mitochondrial aconitase inactivation, a marker of superoxide production in the kainate model. F2 -IsoPs were measured in microdissected hippocampal CA1, CA3 and dentate gyrus (DG) regions at various times following kainate administration. Kainate produced a large increase in F2 -IsoP levels in the highly vulnerable CA3 region 16 h post injection. The CA1 region showed small, but statistically insignificant increases in F2 -IsoP levels. Interestingly, the DG, a region resistant to kainate-induced neuronal death also showed marked (2.5,5-fold) increases in F2 -IsoP levels 8, 16, and 24 h post injection. The increases in F2 -Isop levels in CA3 and DG were accompanied by inactivation of mitochondrial aconitase in these regions. This marked subregion-specific increase in F2 -Isop following kainate administration suggests that oxidative lipid damage results from seizure activity and may play an important role in seizure-induced death of vulnerable neurons. [source] In vivo and in vitro activity of venom from the endoparasitic wasp Pimpla turionellae (L.) (Hymenoptera: Ichneumonidae)ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 2 2006Ekrem Ergin Abstract The biological activity of venom from Pimpla turionellae L. (Hymenoptera: Ichneumonidae) was examined in vivo toward larvae and pupae of Galleriae mellonella L. (Lepidoptera: Pyralidae), and in vitro toward bacterial and fungal cultures, as well as cultured insect cells. Pupae of G. mellonella were far more susceptible to the venom than larvae. At low doses of venom [0.1 venom reservoir equivalents (VRE)], pupal abdominal mobility was inhibited within 30 min, and by 24 h, all pupae injected with venom concentrations >0.5 VRE were completely paralyzed. These same doses of venom resulted in an inhibition of adult emergence. Host larvae were far less sensitive to wasp venom as evidenced by all venom injected larvae remaining responsive to mechanical stimulation by 1 h post injection, even at concentrations equivalent to 1 venom reservoir. Eventually (>2 h at 25°C), venom-injected larvae became immobile, then flaccid, and all died within 24 h post-injection. At lower concentrations of wasp venom, the onset of paralysis was delayed by comparison to that evoked by 1 VRE, and few host larvae were able to pupate. Development of host larvae to adult emergence was also reduced in a dose-dependent manner, with eclosion completely prevented at high concentrations (>0.5 VRE) of venom. Venom doses <0.5 VRE did not appear to induce paralysis or alter larval development. When venom was incubated with bacterial or fungal cultures, no antimicrobial activity was detected. However, wasp venom was found to be cytotoxic and cytolytic to cultured cells derived from the cabbage looper Trichoplusia ni Hubner (Lepidoptera: Noctuidae) and the yellow fever mosquito, Aedes aegypti (L.) (Diptera: Culcidae). Though both cell types displayed similar susceptibility in terms of LC50s, the lepidopteran cells responded much more rapidly with regard to the onset of morphological changes and the timing of cell death. A possible mode of action for the venom is discussed. Arch. Insect Biochem. Physiol. 61:87,97, 2006. © 2006 Wiley-Liss, Inc. [source] Enhanced antitumor efficacy of folate-linked liposomal doxorubicin with TGF-, type I receptor inhibitorCANCER SCIENCE, Issue 10 2010Yukimi Taniguchi Tumor cell targeting of drug carriers is a promising strategy and uses the attachment of various ligands to enhance the therapeutic potential of chemotherapy agents. Folic acid is a high-affinity ligand for folate receptor, which is a functional tumor-specific receptor. The transforming growth factor (TGF)-, type I receptor (T,R-I) inhibitor A-83-01 was expected to enhance the accumulation of nanocarriers in tumors by changing the microvascular environment. To enhance the therapeutic effect of folate-linked liposomal doxorubicin (F-SL), we co-administrated F-SL with A-83-01. Intraperitoneally injected A-83-01-induced alterations in the cancer-associated neovasculature were examined by magnetic resonance imaging (MRI) and histological analysis. The targeting efficacy of single intravenous injections of F-SL combined with A-83-01 was evaluated by measurement of the biodistribution and the antitumor effect in mice bearing murine lung carcinoma M109. A-83-01 temporarily changed the tumor vasculature around 3 h post injection. A-83-01 induced 1.7-fold higher drug accumulation of F-SL in the tumor than liposome alone at 24 h post injection. Moreover F-SL co-administrated with A-83-01 showed significantly greater antitumor activity than F-SL alone. This study shows that co-administration of T,R-I inhibitor will open a new strategy for the use of FR-targeting nanocarriers for cancer treatment. (Cancer Sci 2010); 00: 000,000 [source] Tetraamine-Derived Bifunctional Chelators for Technetium-99m Labelling: Synthesis, Bioconjugation and Evaluation as Targeted SPECT Imaging Probes for GRP-Receptor-Positive Tumours,CHEMISTRY - A EUROPEAN JOURNAL, Issue 7 2010Keelara Abiraj Dr. Abstract Owing to its optimal nuclear properties, ready availability, low cost and favourable dosimetry, 99mTc continues to be the ideal radioisotope for medical-imaging applications. Bifunctional chelators based on a tetraamine framework exhibit facile complexation with Tc(V)O2 to form monocationic species with high in vivo stability and significant hydrophilicity, which leads to favourable pharmacokinetics. The synthesis of a series of 1,4,8,11-tetraazaundecane derivatives (01,06) containing different functional groups at the 6-position for the conjugation of biomolecules and subsequent labelling with 99mTc is described herein. The chelator 01 was used as a starting material for the facile synthesis of chelators functionalised with OH (02), N3 (04) and O -succinyl ester (05) groups. A straightforward and easy synthesis of carboxyl-functionalised tetraamine-based chelator 06 was achieved by using inexpensive and commercially available starting materials. Conjugation of 06 to a potent bombesin-antagonist peptide and subsequent labelling with 99mTc afforded the radiotracer 99mTc-N4-BB-ANT, with radiolabelling yields of >97,% at a specific activity of 37,GBq,,mol,1. An IC50 value of (3.7±1.3),nM was obtained, which confirmed the high affinity of the conjugate to the gastrin-releasing-peptide receptor (GRPr). Immunofluorescence and calcium mobilisation assays confirmed the strong antagonist properties of the conjugate. In vivo pharmacokinetic studies of 99mTc-N4-BB-ANT showed high and specific uptake in PC3 xenografts and in other GRPr-positive organs. The tumour uptake was (22.5±2.6),% injected activity per gram (%,IA,g,1) at 1,h post injection (p.i.). and increased to (29.9±4.0),%,IA,g,1 at 4,h p.i. The SPECT/computed tomography (CT) images showed high tumour uptake, clear background and negligible radioactivity in the abdomen. The promising preclinical results of 99mTc-N4-BB-ANT warrant its potential candidature for clinical translation. [source] | ||||||||||