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H. These Results (h + these_result)
Selected AbstractsDifferential responsiveness of MCF-7 human breast cancer cell line stocks to the pineal hormone, melatoninJOURNAL OF PINEAL RESEARCH, Issue 4 2000Prahlad T. Ram The estrogen receptor (ER)-positive MCF-7 human breast cancer cell line has been used extensively for the study of estrogen-responsive human breast cancer. However, various levels of estrogen responsiveness have been described in different stocks of MCF-7 cells. Because we have previously shown that the pineal hormone, melatonin, inhibits proliferation of MCF-7 cells and can modulate ER expression and transactivation, we investigated if various stocks of MCF-7 cells exhibit a differential responsiveness to the anti-proliferative effects of melatonin and the possible mechanisms involved. The MCF-7 stocks (M, O, H) were examined for: (1) mitogenic response to estradiol; (2) steady-state ER mRNA levels; (3) expression of the mt1 melatonin membrane receptor; (4) growth inhibition by melatonin; and (5) melatonin's modulation of expression of the ER and the estrogen-regulated genes, PgR, TGF, and pS2. For all of these parameters, there was a stock-specific response which showed: MCF-7M>MCF-7O>MCF-7 H. These results demonstrate that there are significant differences in the responsiveness of various stocks of MCF-7 breast cancer cells to the growth-inhibitory effects of melatonin which can be correlated with both the level of ER mRNA expression and the degree of estrogen-responsiveness. These findings suggest that not only may these differences have some impact on the cells' estrogen-response pathway, but also that the primary growth-inhibitory effects of melatonin are transduced through the membrane-associated G-protein coupled mt1 melatonin receptor. [source] Randomized trial of trigger point injection for renal colicINTERNATIONAL JOURNAL OF UROLOGY, Issue 9 2002MASANORI IGUCHI Abstract Background: Many drugs have been utilized for the treatment of renal colic, but to date no drugs that relieve pain quickly and completely have been developed. Thus, we conducted a prospective trial to evaluate the effects of trigger point injection on renal colic. In this study, we used a local injection of lidocaine to the trigger point of patients experiencing renal colic, and evaluated the efficacy in patients using the visual analog scale. Methods: Sixty patients with renal colic were enrolled in this study and divided into two groups by a simple randomization: (i) the butylscopolamine group (n = 30, intravenous injection of butylscopolamine bromide and sulpyrine); and (ii) the lidocaine group (n = 30, local anesthesia to the trigger point with lidocaine). Results: Renal colic had disappeared completely at the end of the trigger point injection in 15/30 patients and the average time required to produce a 50% improvement in symptoms was 9 min in all patients in the group. In the lidocaine group, only one patient needed an additional anodyne treatment after 60 min and none of the 29 patients whose pain disappeared within 60 min needed further anodyne treatment within 24 h. These results were all significantly superior to those of the conventional treatment. No side-effects and complications were observed. Conclusion: Trigger point injection, in our experience, is an easy, safe and effective method for the amelioration of renal colic. It was significantly superior to the combination of intravenous butylscopolamine and sulpyrine. [source] Effect of temperature on pharmacokinetics of enrofloxacin in mud crab, Scylla serrata (Forsskål), following oral administrationJOURNAL OF FISH DISEASES, Issue 3 2008W H Fang Abstract The study was conducted to evaluate the pharmacokinetics of enrofloxacin following a single oral gavage (10 mg kg,1) in mud crab, Scylla serrata, at water temperatures of 19 and 26 °C. Enrofloxacin concentration in haemolymph was determined using high-performance liquid chromatography (HPLC). A multiple and repeated haemolymph sampling from the articular cavity of crab periopods was developed. The haemolymph of an individual crab was successfully sampled up to 11 times from the articular cavity. The profile of haemolymph enrofloxacin concentration of an individual crab versus time was thus achieved. The mean haemolymph enrofloxacin concentration versus time was described by a two-compartment model with first-order absorption at two water temperatures. The peak concentrations of haemolymph enrofloxacin at 19 and 26 °C were 7.26 and 11.03 ,g mL,1, at 6 and 2 h, respectively. The absorption and distribution half-life time ( and t1/2,) at 19 °C were 3.7 and 4.5 h, respectively, which were markedly larger than the corresponding values (1.1 and 1.5 h) at 26 °C; the elimination half-life time (t1/2,) was 79.1 and 56.5 h at 19 and 26 °C, respectively. The area under curve (AUC), total body clearance (Cl) and mean residence time (MRT0,,) at 19 °C were 636.0 mg L,1 h, 0.016 L h,1 kg,1 and 102.5 h, respectively; the corresponding values at 26 °C were 583.4 mg L,1 h, 0.018 L h,1 kg,1and 63.7 h. These results indicate that enrofloxacin is absorbed and eliminated more rapidly in mud crab at 26 °C than at 19 °C. [source] COMPARATIVE STUDY OF SHELL SWAB AND SHELL CRUSH METHODS FOR THE RECOVERY OF SALMONELLA FROM SHELL EGGSJOURNAL OF FOOD SAFETY, Issue 4 2008T. KAWASAKI ABSTRACT Swabbing is the standard methodology for the recovery of resident microorganism from shell eggs in Japan. A comparative study of shell swab (SW) and shell crush (CR) techniques was performed to recover the laboratory-inoculated Salmonella from shell eggs. It was found that the recovery of Salmonella by CR methods was significantly higher (4.5,7.5 log cfu/egg) than that of SW methods (3.1,6.3 log cfu/egg). However, analyses with quantitative real-time polymerase chain reaction (invA as a target gene), fluorescent microscopic and quantitative analyses with a Live/Dead BacLight bacterial viability kit revealed that not all of the inoculated Salmonella spp. populations were recovered as intact cells by either method. The chemiluminescent bacterial viability assay showed that chemiluminescence intensity (CI) began to increase after 30 min in CR samples; on the other hand, SW samples did not show any increase in CI for 2 h. These results suggest that SW might cause more damage and lethality to cells than CR. In addition, to determine the most appropriate method for recovering resident aerobic bacteria, coliforms and Salmonella spp from shell eggs, 4,000 commercial eggs were collected and sampled by shell rinse (SR) and CR techniques using phosphate-buffered saline (PBS) warmed to different temperatures. PBS at 37C was found to be the best recovery solution and temperature, respectively, for recovering aerobic microorganisms from shell eggs by both methods and the CR methods recovered a higher population than did the SR methods (4.9 versus 5.8 log cfu/egg for SR and CR methods, respectively; n = 500 eggs/method). Therefore, the CR method along with recovery buffer (PBS) at 37C could be an effective technique for the recovery of microorganisms from post-processed shell eggs. PRACTICAL APPLICATIONS There is a need to develop a rapid and highly sensitive method for the recovery of microorganisms from shell eggs. Such recovery methods are also useful for evaluating the efficacy of newly developed shell egg disinfection techniques. Many methods involving rinsing, swabbing, and crushing of shell eggs have been reported; however, we performed a comparative study of the method used to recover the Salmonella from shell eggs. We found that the shell crush method (CR) was superior to the shell swab method (SW) for the recovery of Salmonella spp., and phosphate-buffered saline (PBS) at 37C was found to be the best recovery solution and temperature, respectively, for recovering microorganisms from shell eggs by both methods. Therefore, the CR method along with recovery buffer (PBS) at 37C could be an effective technique for the recovery of microorganisms from post-processed shells. Use of this method could be recommended for the microbial evaluation of post-processed shell eggs in industries. [source] Hyalgan® has a dose-dependent differential effect on macrophage proliferation and cell deathJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2003Kyle M. Sheehan Abstract The intra-articular injection of high molecular weight hyaluronic acid (HA) has been reported to be an effective treatment for pain of osteoarthritis of the knee. However, the mechanism by which HA exerts its effect is unknown. To explore HA's influence on the growth of U937 human macrophages, cells were incubated for 168 h with three concentrations, 1, 0.1 and 0.01 mg/mL, of Hyalgan®, a high molecular weight HA preparation. At 24-h increments, the cells were examined for proliferation, cell cycle distribution as well as the number of apoptotic and dead cells. Exposing macrophages to 1 mg/mL Hyalgan® significantly reduced the rate of cellular proliferation and altered the cell cycle distribution to yield decreased proportions of G0/G1 cells but increased S and G2/M cells. Concomitantly, a 10-fold increase in apoptotic cells and a 12-fold increase in dead cells were observed. The population doubling time (PDT) for cells treated with 1.0 mg/mL Hyalgan® increased from 23.6 to 52.9 h. By contrast, the two lower Hyalgan® concentrations significantly promoted macrophage proliferation in a dose-dependent manner. They also increased the proportion of G2/M cells, but had no effect on the number of apoptotic or dead cells. The PDTs of 21.5 and 22.2 h were less than the control time of 23.6 h. These results demonstrate that Hyalgan® concentrations have a differential effect on macrophage growth dynamics and suggest an anti-inflammatory effect at high HA concentrations. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Activation of MMP-2 by Porphyromonas gingivalis in human periodontal ligament cellsJOURNAL OF PERIODONTAL RESEARCH, Issue 2 2003Kassara Pattamapun It has been reported that matrix metalloproteinase (MMP) produced by host cells plays a major role in periodontal tissue destruction. In addition, secreted virulence factors from Porphyromonas gingivalis can alter MMP secretion and cause activation in host cells that lead to the tissue degradation. In this study, we examine the effects of P. gingivalis supernatant on matrix metalloproteinase-2 (MMP-2) activation in human periodontal ligament (HPDL) cells. Cultures of HPDL cells were treated with P. gingivalis supernatant for 48 h and the level of MMP-2 activation was monitored by gelatin zymography. The profound activation of MMP-2 was seen only in the treated group. The activation of MMP-2 was inhibited by MMP inhibitors phenanthroline and EDTA, but not serine protease or cysteine protease inhibitors. To study the correlation between the expression of membrane-type-1 matrix metalloproteinase (MT1-MMP) and the activation of MMP-2, the level of MT1-MMP was analyzed. The results from reverse-transcription polymerase chain reaction (RT-PCR) and Western analysis indicated that P. gingivalis supernatant up-regulated the expression of MT1-MMP in both transcription and translation levels within 48 h. These results suggest that P. gingivalis supernatant can activate MMP-2 in HPDL cells and the mechanism of activation may involve the increased amount of MT1-MMP. It is possible that the activation of MMP-2 by P. gingivalis plays a role in the process of chronic periodontitis. [source] Acute Toxicity and Sublethal Effects of Nitrite on Selected Hematological Parameters and Tissues in Dark-banded Rockfish, Sebastes inermisJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2007In-Seok Park Acute toxicity and sublethal effects of nitrite in dark-banded rockfish, Sebastes inermis (83.3 ± 7.2 g), were studied under static conditions for a period of 96 h. The acute toxicity of nitrite evaluated for the 96-h lethal concentration (LC50) was 700 mg/L. The sublethal effects on selected hematological parameters of S. inermis, such as total erythrocyte count (TEC), hemoglobin, plasma glucose, and serum protein content, were measured after 0, 6, 12, 24, 48, 72, and 96 h of exposure to 0, 50, 100, 200, 400, and 700 mg/L of nitrite. Sublethal nitrite caused progressive reduction in the TEC, hemoglobin, and serum protein content in fish depending on the nitrite concentration and exposure period. The 96-h exposure resulted in a 14,42% reduction in TEC and 25,33% reduction in hemoglobin content for 100,700 mg/L of nitrite compared to the control. A dose-related reduction in plasma glucose (25.7,34.2%) was observed for concentrations of 200,700 mg/L of nitrite during 48 h of exposure, followed by an increase through 96 h. A significant reduction in serum protein (7.3,12.6%) was observed for 200,700 mg/L of nitrite after 96 h of exposure. Abnormal histological changes in skin, gill, liver, and kidney tissue were observed in fish exposed to 700 mg/L of nitrite after 96 h of exposure compared to the control. Although no mortality of S. inermis occurred at 500 mg/L of nitrite, all hematological parameters adversely responded to a nitrite dose of 200 mg/L for 96 h. These results showed that although acute toxicity concentration of nitrite in S. inermis is higher than 700 mg/L, sublethal concentrations of nitrite also negatively affect hematological parameters. [source] Protective effect of vitamin E on ultraviolet B light,induced damage in keratinocytesMOLECULAR CARCINOGENESIS, Issue 3 2002Samar Maalouf Abstract Ultraviolet (UV) B radiation is the most common environmental factor in the pathogenesis of skin cancer. Exposure of human skin to UVB radiation leads to the depletion of cutaneous antioxidants, the activation of nuclear factor kappa B (NF-,B), and programmed cell death (apoptosis). Although antioxidant supplementation has been shown to prevent UVB-induced photooxidative damage, its effect on components of cell signaling pathways leading to gene expression has not been clearly established. In the present study, the effect of the antioxidant vitamin, ,-tocopherol (,-T), and its acetate analog, ,-tocopherol acetate (,-TAc), on UVB-induced damage in primary and neoplastic mouse keratinocytes was investigated. The ability of both vitamins to modulate UVB-induced apoptosis and activation of the transcription factor NF-,B were studied. Treatment of normal and neoplastic mouse epidermal keratinocytes (308 cells) with 30,60 mJ/cm2 UVB markedly decreased viable cell number and was accompanied by DNA fragmentation. When both vitamins were applied to cells at times before and after UVB radiation, a significant increase in the percentage of viable cells and concomitant decrease in the number of apoptotic cells was noted, with vitamin pretreatment providing a better protection than posttreatment. Simultaneous posttreatment of irradiated cells with ,-TAc abolished the cytotoxic effects of UVB and restored cell viability to control levels. In addition, simultaneous posttreatment of irradiated cells with ,-T reduced the number of apoptotic cells by half, indicating a synergistic effect of two such treatments compared with any single one. Flow cytometry analysis indicated that vitamin treatment suppressed both an increase in pre-G0 cells and a decrease in cycling cells by UVB exposure. In addition, NF-,B activation was detected 2 h after UV exposure and was maintained for up to 8 h. Pretreatment with vitamins significantly inhibited NF-,B activation at 4 and 8 h. These results indicate that vitamin E and its acetate analog can modulate the cellular response to UVB partly through their action on NF-,B activation. Thus, these antioxidant vitamins are potential drugs for the protection from or the reduction of UVB-associated epidermal damage. © 2002 Wiley-Liss, Inc. [source] The responsive expression of heat shock protein 22 gene in zhikong scallop Chlamys farreri against a bacterial challengeAQUACULTURE RESEARCH, Issue 2 2010Lei Zhang Abstract HSP22 is a member of a small HSP subfamily contributing to the growth, transformation and apoptosis of the cell as well as acting as a molecular chaperone. In the present study, CfHSP22 cDNA was cloned from Chlamys farreri by the rapid amplification of cDNA ends technique. The full-length cDNA of CfHSP22 was of 1279 bp, consisting of a 5,-terminal untranslated region (5,UTR) of 122 bp, a 3,UTR of 581 bp with a canonical polyadenylation signal sequence AATAAA and a poly(A) tail, and an open reading frame of 576 bp encoding a polypeptide with a molecular mass of 22.21 kDa and a predicted isoelectric point of 9.69. There was an ,-crystallin domain, a hallmark of the sHSP subfamily, in the C-terminus, and the deduced amino acid sequence of CfHSP22 showed high similarity to previously identified HSP22s. CfHSP22 was constitutively expressed in the haemocyte, muscle, kidney, gonad, gill, heart and hepatopancreas, and the expression level in the hepatopancreas was higher than that in the other tissues. CfHSP22 transcription was up-regulated and reached a maximal level at 12 h after the bacterial challenge, and then declined progressively to the original level at 48 h. These results suggested that CfHSP22 perhaps play a critical role in response to the bacterial challenge in haemocytes of scallop C. farreri. [source] Design of a cytochrome P450BM3 reaction system linked by two-step cofactor regeneration catalyzed by a soluble transhydrogenase and glycerol dehydrogenaseBIOTECHNOLOGY PROGRESS, Issue 5 2009Tsuyoshi Mouri Abstract A cytochrome P450BM3-catalyzed reaction system linked by a two-step cofactor regeneration was investigated in a cell-free system. The two-step cofactor regeneration of redox cofactors, NADH and NADPH, was constructed by NAD+ -dependent bacterial glycerol dehydrogenase (GLD) and bacterial soluble transhydrogenase (STH) both from Escherichia coli. In the present system, the reduced cofactor (NADH) was regenerated by GLD from the oxidized cofactor (NAD+) using glycerol as a sacrificial cosubstrate. The reducing equivalents were subsequently transferred to NADP+ by STH as a cycling catalyst. The resultant regenerated NADPH was used for the substrate oxidation catalyzed by cytochrome P450BM3. The initial rate of the P450BM3-catalyzed reaction linked by the two-step cofactor regeneration showed a slight increase (approximately twice) when increasing the GLD units 10-fold under initial reaction conditions. In contrast, a 10-fold increase in STH units resulted in about a 9-fold increase in the initial reaction rate, implying that transhydrogenation catalyzed by STH was the rate-determining step. In the system lacking the two-step cofactor regeneration, 34% conversion of 50 ,M of a model substrate (p-nitrophenoxydecanoic acid) was attained using 50 ,M NADPH. In contrast, with the two-step cofactor regeneration, the same amount of substrate was completely converted using 5 ,M of oxidized cofactors (NAD+ and NADP+) within 1 h. Furthermore, a 10-fold dilution of the oxidized cofactors still led to approximately 20% conversion in 1 h. These results indicate the potential of the combination of GLD and STH for use in redox cofactor recycling with catalytic quantities of NAD+ and NADP+. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] Expression analyses and transcriptional regulation of mouse nucleolar spindle-associated protein gene in erythroid cells: essential role of NF-YBRITISH JOURNAL OF HAEMATOLOGY, Issue 4 2006Tohru Fujiwara Summary Nucleolar spindle-associated protein (NuSAP), a recently characterised microtubule-associated protein, appears to participate in cell cycle regulation. It has been demonstrated that NuSAP is expressed preferentially in the erythroid lineage in haematopoietic cells. To characterise its role in erythropoiesis, we examined the expression profile of the NuSAP gene. In fractionated murine erythroblasts, NuSAP mRNA was remarkably more abundant in the subset corresponding to immature erythroblasts (TER119+CD71high) than mature erythroblasts (TER119+CD71low), and it was significantly increased in TER119+ cells from in vivo phlebotomised mice compared with control mice. Furthermore, during erythroid maturation of mouse erythroleukaemia (MEL) cells by dimethylsulfoxide, NuSAP mRNA was increased at 24,72 h. These results suggested that the NuSAP gene might contribute to the expansion of immature erythroblast pool. The regulatory mechanism of NuSAP gene was investigated using MEL cells. Sequence analysis revealed that NuSAP promoter has four CCAAT boxes, an Sp1 element, a GATA-like element, a CACCC element, a Myb element and lacks a TATA box. Promoter analyses demonstrated that duplicated CCAAT boxes located at ,81/,85 and ,30/,34 were essential for promoter activity. Furthermore, the promoter was trans -activated by NF-YA through these elements. These results suggest that NuSAP might play an important role in erythroid proliferation under the control of NF-Y. [source] | ||||||||||||||||