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151.
Myocardial ischemia-reperfusion (I/R) is associated with the activation of matrix metalloproteinases (MMPs) and serine proteases. We hypothesized that activation of MMPs and the serine protease plasmin contribute to early cardiac myocyte death following I/R and that broad-spectrum protease inhibition with doxycycline (DOX) preserves myocyte viability. Rats treated daily with or without DOX beginning 48 h prior to experimentation were subjected to 30 min of coronary occlusion and 2 days of reperfusion. DOX pre-treatment reduced infarct size by 37%. DOX attenuated increases in MMP-9 and plasmin levels as determined by gelatin zymography and immunoblot, respectively. Neutrophil extravasation was unaltered by DOX as assessed by myeloperoxidase (MPO) activity. To examine the contribution of MMP-9 and plasmin to myocyte injury, cultures of neonatal rat ventricular myocytes (NRVMs) were treated for 48 h with 83 kDa MMP-9 or plasminogen in the presence or absence of DOX. MMP-9 treatment did not affect myocyte viability. Plasminogen treatment led to increased plasmin activity, resulting in loss of 1-integrin, NRVM detachment and apoptosis. DOX co-treatment inhibited plasmin activity and preserved NRVM attachment, whereas co-treatment with the broad-spectrum MMP inhibitor GM6001 had no effect. These results indicate that plasmin causes disruption of myocyte attachment and viability independently of MMP activation in vitro and that inhibition of plasmin by DOX may reduce I/R-induced myocyte death in vivo through the inhibition of plasmin. (Mol Cell Biochem 270: 1–11, 2005)  相似文献   
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Summary Media components used for three stages of development: (1) callus maintenance, (2) maturation of embryos, and (3) conversion of embryos to plants were shown to affect regeneration of plants for the commercially important red rose cultivar Kardinal. Embryogenic callus was maintained for 5yr on either Schenk and Hildebrandt’s basal salts medium (SH) supplemented with 13.6 μM 2,4-dichlorophenoxyacetic acid (2,4-D) or Murashige and Skoog’s basal salts medium (MS) supplemented with 18.1 μM dicamba and 0.46 μM kinetin. Maturation of embryos was three times higher using callus maintained on the SH medium supplemented with 2,4-D while conversion of cotyledonary-stage embryos to plants was significantly higher (10 times) using callus that had been maintained on MS medium with dicamba and kinetin. Maximum maturation (13.5%), and conversion (15.2%), occurred when callus was cultured on MS maturation medium without hormones. Cotyledonary-stage embryos cultured on MS conversion medium supplemented with abscisic acid (5–20 μM) produced plants that survived at a significantly higher rate (two times) in the greenhouse than when embryos were cultured without abscisic acid. The highest rate of plant regeneration occurred when embryogenic callus of ‘Kardinal’ was maintained on MS medium supplemented with dicamba and kinetin, maturation of embryos occurred on MS maturation medium without hormones, and conversion of cotyledonary-stage embryos occurred on MS conversion medium supplemented with abscisic acid.  相似文献   
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We investigated the influence of vitamin D receptor (VDR) polymorphisms and vitamin D level on the blood pressure and the risk of preeclampsia. In a case-control study, 200 pregnant women, including 100 individuals with preeclampsia along with 100 healthy pregnant women, were studied for VDR FokI, TaqI, and BmsI polymorphisms and serum 25 (OH)-D level using polymerase chain reaction-restriction fragment length polymorphism method and commercial kit, respectively. The mean level of 25 (OH)-D in preeclamptic patients was significantly lower (16.6 ± 4.2 ng/mL, P < 0.001) compared with controls (19.6 ± 3.8 ng/mL). Among all women, a significantly higher systolic blood pressure and before-pregnancy body mass index and also lower gestational age were observed in the presence of 25 (OH)-D level < 20 ng/mL compared with the 20 to 30 ng/mL. A significantly higher frequency of VDR FokI C allele in preeclamptic patients (83%) than controls (74%) was associated with a 1.72-fold increased risk of preeclampsia. In all the studied individuals, the systolic and diastolic blood pressures were significantly higher in the presence of the FokI CC genotype compared with the TC and TT+TC genotypes. Neither VDR Taq1 nor VDR BmsI was associated with the risk of preeclampsia. The haplotype FokI C, TaqI C and BmsI A (CCA) compared with haplotype CTG increased the risk of preeclampsia by 1.4-fold (P = 0.33). Our study suggests an association between VDR FokI polymorphism and an insufficient serum level of 25 (OH)-D with the risk of preeclampsia and also the influence of insufficient 25 (OH)-D level and VDR FokI polymorphism on maternal factors, including blood pressure.  相似文献   
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Epilepsy is one of the most common neurological disorders and is characterized by recurrent, unprovoked epileptic seizures. Seizures are generated by spontaneous, synchronous neuronal discharges which induce disturbances of perception or behaviour. About one third of all epilepsies are primarily caused by genetic factors. These so-called idiopathic epilepsies occur without observable structural alterations in the brain. Mutations in genes encoding neuronal ion channels play a central role in the etiology of such epilepsies. In this review, mutations in ion channel genes associated with idiopathic epilepsies and their functional consequences are described. The underlying pathomechanisms and consequences for treatment are discussed.  相似文献   
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An efficient callus induction and plant regeneration system has been standardized for an ethnomedicinal plant, Elephantopus scaber Linn. Two explants i. e. seeds and leaf segments were used for callus induction. Murashige and Skoog (MS) medium supplemented with 5.0 μM 2, 4-dichlorophenoxy acetic acid (2, 4-D) and 0.5 μM kinetin (Kn) gave the optimum frequency (89 %) of callus induction from seed explant. The results showed that the highest response in terms of percent callus regenerating (91 %) and number of shoots (56) per culture was recorded on MS medium supplemented with 6.0 μM N6-benzylaminopurine (BA) and 1.5 μM α naphthalene acetic acid (NAA). The best rooting of regenerated shoots was obtained on half strength MS medium supplemented with 6.0 μM indole-3- butyric acid (IBA). On this medium, 100 % of the shoots produced roots with a mean number of 3.2 roots per shoot. The positive role of vesicular arbuscular mycorrhizae (VAM) along with potting mix has been well established in the present study. Of the various potting mix employed for plant acclimatization, the highest response of 100 % plant survival was noticed when autoclaved garden soil, sand (2:1) and VAM was utilized as potting mix. Inter-simple sequence repeats (ISSR) were used to establish the clonal fidelity of regenerated plantlets and the banding profiles from callus derived plants were monomorphic and similar to those of mother plant, thus ascertaining the true-to-type nature of these plants.  相似文献   
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Complexes of 4-(((2-aminopyridin-3-yl)methylene)amino)benzoic acid ligand with cobalt(II) (1), nickel(II) (2), copper(II) (3), zinc(II) (4) and palladium(II) (5) are synthesized and characterized by using different spectroscopic methods like, UV–Visible, infrared, 1H, 13C NMR, molar conductance, ESR and elemental analysis. Quantum chemical computations were made using DFT (density functional theory), B3LYP functional and 6-31+?+G(d,p)/SDD basis set in order to determine optimized structure parameters, frontier molecular orbital parameters and NLO properties. Based on DFT and experimental evidence, the complexes ensured that the octahedral geometry have been proposed for complexes 1, 2 and 4, square planar for complexes 3 and 5. All the complexes showed only residual molar conductance values and hence they were considered as non-electrolytes in DMF. In addition, the anti-proliferative activity of the compounds was evaluated against different human cancer cell lines (IMR-32, MCF-7, COLO205, A549, HeLa and HEK 293) and cisplatin is used as a reference drug. Compounds 1 and 4 showed remarkable cytotoxicity in five cancer cell lines tested except MCF-7. Also, the compounds were examined for their in vitro antimicrobial and scavenging activities. The molecular docking results are well corroborated with the experimental anticancer activity results.

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