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PubMedDate not supplied

[Serum copper levels in early pregnancy complicated by symptoms of spontaneous abortion and infection].

INTRODUCTION: The study evaluates serum levels of copper, chorionic gonadotropin, estradiol, progesterone and prolactin in patients with symptoms of miscarriage and in uncomplicated pregnancies in cases with or without cervical or vaginal infections detected by vaginal or cervical smears, as well as Chlamydia testing. MATERIAL AND METHODS: The study included 50 patients with symptoms of threatening miscarriage and 50 patients with uncomplicated pregnancies. Hormone levels were determined by ELISA method and copper was evaluated by acid medium colorimetry. RESULTS: We found that values of serum copper, estradiol, progesterone and prolactin were significantly lower in patients with lower genital tract infection. CONCLUSION: Decreased levels of serum copper could be used as a method of choice for detecting infection during the first trimester of pregnancy.

Abortion, Threatened↗

PubMed2000

Blood lead level to induce significant increase in urinary delta-aminolevulinic acid level among lead-exposed workers: a statistical approach.

The present study was initiated to examine the quantitative relationship between blood lead (Pb-B) and urinary delta-aminolevulinic acid (ALA-U) among Pb-exposed workers, and to find a threshold Pb-B level to induce an increase in ALA-U. For this purpose, pairs of venous blood and spot urine samples were collected from 8,274 men and 5,856 women (14,130 workers in total) who were occupationally exposed to inorganic lead. The blood and urine samples were analyzed for Pb-B and ALA-U by atomic absorption spectrometry and colorimetry, respectively, and the correlation between pairs of measures were subjected to statistical analysis. The assumption of the 3rd degree regression for correlation gave a substantially greater correlation coefficient (0.645 for men and 0.619 for women) than 1st or 2nd degree regression, whereas only very small improvement in the coefficient was achieved with 4th to 6th degree ones. Logarithmic conversion of the parameters was not effective in improving the correlation. The assumption of the 3rd degree regression followed by calculation of the local minimum gave 22, 29 and 23 micrograms/100 ml Pb-B for men, women, and men + women, respectively, as the threshold Pb-B to induce ALA-U increase. Pb-B to elevate ALA-U to the 95% upper normal limit (8 mg/l, common to men and women) was 62, 50 and 58 micrograms/100 ml for men, women and men + women, respectively. The validity of the 3rd degree regression assumption as a tool to calculate a threshold from experimental or epidemiological data is discussed.

Adult↗

PubMed2006

Green chemistry in urinalysis for trichloroethanol and trichloroacetic acid as markers of exposure to chlorinated hydrocarbon solvents.

The aim of the present study was to develop a method of urinalysis for trichloroacetic acid (TCA) and trichloroethanol (TCE), and therefore total trichloro-compounds (TTC) as the sum, with least use of hazardous chemicals, being green in that sense. After acid hydrolysis followed by dilution with an ethanol (EtOH)-methanol (MeOH)-water mixture, capillary gas-choromatography with an electron-capture detector can quantify TCA and TCE in the diluted hydrolyzate. Comparison studies showed that the results were identical among three methods, i.e., 1. the method developed in the present study, 2. a head-space GC with acid hydrolysis of conjugated TCE and methyl-esterification of TCA, and 3. traditional colorimetry with Fujiwara reaction. When applied to exposure-excretion analysis, the three methods gave results reproducible to each other. Over-all evaluation therefore was such that the method developed in the present study is as equally reliable as previously developed methods. It should be further noted that the procedures are very simple, with minimum use of occupationally or environmentally hazardous chemicals. In case the determination of only TCA is requested, it is possible to skip the hydrolysis step so that the treatment prior to the GC analysis is even simpler, i.e., just a 60-fold dilution of the urine sample with the EtOH-MeOH-water mixture. It was also demonstrated that correction of urinary analyte levels for urine density in terms of creatinine or specific gravity did not improve the correlation with the intensity of TRI exposure.

Biomarkers↗

PubMed1992

The effect of calcitonin-gene-related peptide on acute ischemia-reperfusion renal injury: ultrastructural and membrane lipid peroxidation studies.

It is well accepted that postischemic reperfusion promotes functional and morphological impairment which may be related to oxygen free-radical-mediated membrane damage. A new purified bioactive compound, calcitonin-gene-related peptide (CGRP), is known to be not only a potent vasodilator but also a cytoprotective agent. This study was designed to observe whether CGRP has a protective effect on the ischemic kidney. Male Sprague-Dawley rats were subjected to a 45-min period of renal ischemia followed by 60 min of reperfusion. At the beginning of the reperfusion, 12 rats were given intravenous saline and served as controls whereas 5 rats were given CGRP, 10 micrograms/kg intravenously. After reperfusion the kidneys were removed for light- and electronmicroscopy, and the lipid peroxidation product malonaldehyde (MDA) was assayed by thiobarbituric acid (TBA) colorimetry. The results demonstrated that the serum creatinine (Scr) and renal MDA content in the CGRP group were significantly lower than those in the control group. The mean values for Scr were 0.75 +/- 0.09 vs 0.93 +/- 0.05 mg/dL or 62.8 +/- 9.7 vs 82.2 +/- 4.4 mumol/L (p less than 0.05), respectively; while the mean values for MDA were 18.71 +/- 2.13 vs 30.32 +/- 1.78 nmol/100 mg (ww) (p greater than 0.05), respectively. The same signals of free radicals in the ischemic-reperfused kidney with or without CGRP were found by electron spin resonance. Morphological studies demonstrated that the treatment with CGRP ameliorated the ischemic-reperfusion injury to both renal brush borders and mitochondria. The results showed that CGRP has a protective action on ischemia-reperfusion renal injury by decreasing lipid peroxidation of membranes and suggest that it may be a beneficial agent for therapy of acute renal failure.

Animals↗

PubMed1981

Ionized calcium in body fluids.

This article will review the methods currently available to the clinician and research worker for measuring the concentration of ionized calcium in various body fluids including whole blood, serum, plasma, urine, cerebrospinal fluid, milk, and synovial fluid. The methods to be reviewed are based on procedures involving bioluminescence, colorimetry and ion-selective electrodes. Emphasis will be given to the precision and, wherever possible, accuracy of each technique. Possible sources of error and interfering agents will be identified. Attention will be given to the recommended conditions for measuring ionized calcium in each body fluid. An assessment will be made of the theoretical and practical importance of measuring ionized calcium rather than total calcium and of its value in clinical medicine.

Adult↗

PubMed1984

Recent advances in glycosylated hemoglobin measurements.

Glycosylated hemoglobins have gained wide acceptance as an accurate index of long-term blood glucose control in diabetes mellitus. A variety of glycosylated hemoglobin assays is available. There is a high degree of correlation between results determined by these assays. The ideal laboratory method for measuring glycosylated hemoglobin in the diabetic should be accurate, precise, easily standardized, inexpensive, and rapidly performed. Unfortunately, none of the currently used methods meet all of the criteria necessary to be considered the ideal laboratory method. The most widely used methods for quantitating glycosylated hemoglobins--including ion exchange chromatography, electrophoresis, isoelectric focusing, thiobarbituric acid colorimetry, and affinity chromatography--are reviewed with respect to the important advantages and disadvantages of each method for the clinical laboratory. Techniques for quantitating glycosylated proteins other than hemoglobins, such as albumin, are also discussed.

Blood Specimen Collection↗

PubMed2004

Sources of variation in rates of in vitro ruminal protein degradation.

Rates and extents of ruminal protein degradation for casein, solvent soybean meal (SSBM), expeller soybean meal (ESBM), and alfalfa hay were estimated from net appearance of NH3 and total amino acids in in vitro media containing 1 mM hydrazine and 30 mg/L of chloramphenicol. Protein was added at 0.13 mg of N/mL of medium, and incubations were conducted for 4 to 6 h, usually with hourly sampling. Inocula were obtained from ruminally cannulated donor cows fed diets of grass silage or alfalfa and corn silages plus concentrates. Preincubation or dialysis of inocula was used to suppress background NH3 and total amino acids; however, preincubation yielded more rapid degradation rates for casein and SSBM and was used in subsequent incubations. Preincubation with added vitamins, VFA, hemin, or N did not alter protein degradation. Protein degradation rates estimated for SSBM, ESBM, and alfalfa were not different when computed from total N release or N release in NH3 plus total amino acids, regardless of whether amino acids were quantified using ninhydrin colorimetry or o-phthalaldehyde fluorescence. Accounting for the release of peptide-N also did not affect estimated degradation. However, casein degradation rates were more rapid when using total N release or accounting for peptide-N, indicating significant accumulation of small peptides during its breakdown. Rates also were more rapid with inocula from lactating cows versus nonlactating cows with lower feed intake. Protein degradation rates were different due to time after feeding: casein rate was more rapid, but SSBM and ESBM rates were slower with inocula obtained after feeding. Several characteristics of ruminal inoculum that influenced breakdown of the rapidly degraded protein casein did not appear to have direct effects on degradation of protein in soybean meal.

Amino Acids↗

PubMed1979

Estrogen in plasma of parturient paretic and normal cows.

The endocrine factors associated with parturient paresis have not been defined totally. Estrogens stimulate uptake of calcium by bone. Since secretion of estrogen increases dramatically as parturition approaches, estrogen may be involved in homeostatic mechanisms regulating calcium metabolism. Plasma was collected for 30 days (-30) prepartum to 5 days (+5) postpartum from six Holstein and nine Jersey cows approaching three or more lactations. Of all cows, six Jerseys contracted parturient paresis. Estradiol and estrone were analyzed by radioimmunoassay, total calcium and total magnesium by atomic absorption spectrophotometry, and total phosphorus by colorimetry. Data were grouped into periods respresenting days -30 to -21, -20 to -11, -10 to -6, -5 to -4, -3 to -2, -1, 0 (parturition), +1, +2 to +3, and +4 to +5. Calcium in plasma was lower in parturient paresis cows on days +1 and +2 to +3, and magnesium was higher during the same periods but lower on days -4 to -5. Total phosphorus, estrone, and estradiol of normal cows and those with parturient paresis were not different. During the entire sampling period, phosphorus and estradiol were similar in both groups while magnesium was higher and calcium lower in cows with parturient paresis. Estrone was lower in cows with parturient paresis. Lower estrone in cows with parturient paresis may be predisposing for parturient paresis.

Animals↗

PubMed1985

Determination of lactose by an enzymatic method.

The general methodology used for the determination of lactose in milk is considered, namely, polarimetry, gravimetry, infrared, colorimetry, gas-liquid chromatography, and high pressure liquid chromatography. The criteria for selecting an ideal analytical method followed by the relevance of most of these criteria in enzymatic methodology are discussed. The principle of the Boehringer-Mannheim method is presented, i.e., lactose is hydrolyzed to glucose and beta-galactose in the presence of beta-galactosidase and water. beta-Galactose is then oxidized by nicotinamide-adenine dinucleotide to galactonic acid in the presence of beta-galactose dehydrogenase. The amount of reduced nicotinamide-adenine dinucleotide formed is stoichiometric with the amount of lactose and is measured at 340 nm in a spectrophotometer possessing a slit width of less than or equal to 10 nm. The results of a recent Association of Official Analytical Chemists collaborative study of the B-M method are presented. From the overall mean of results on all samples, determinations by the enzymatic method averaged .49% lower than by the Association of Official Analytical Chemists gravimetric method. Standard deviations were similar for three sets of blind duplicates, which ranged between 3.67 and 4.55% lactose. F-Values revealed that variations between means obtained by laboratories differed significantly as compared with variations within laboratory means. The method has received Official First Action recognition by Association of Official Analytical Chemists.

Animals↗

PubMed2000

A quantitative evaluation of pigmented skin lesions using the Lab* color coordinates.

The evaluation of pigmentary skin lesions by clinical doctors has been based on subjective and qualitative judgements. Observations have mostly relied on visual inspection, making the effects of treatment difficult to evaluate with any precision. For this reason there is a real need for an objective method to evaluate prognosis after treatment. Recent scientific measurements such as reflectance spectrophotometry and reflectance colorimetry have provided accurate quantitative color information about skin lesions, but these techniques are costly and difficult to apply in the clinical field. The purpose of this study was to develop a simple and cost-effective way of evaluating treatment results. We have developed a software program using the L*a*b* color coordinate system to quantify the effect of treatment and have successfully demonstrated its clinical usefulness. Our method compares the relative color difference between normal skin and skin lesions before and after treatment, instead of measuring the absolute color of skin lesions. The accuracy of our quantitative color analysis was confirmed by the simulated images of hemangioma and ota nevus. Clinical efficacy was also confirmed through a blind test involving 3 clinicians who were asked to grade the treatment effects of 13 cases of hemangioma and 7 cases of ota nevus. These subjective clinical grades correlated well with the treatment results obtained using the proposed color analysis system (Correlation coefficient = 0.84).

Color↗

PubMed1982

Effect of 3-nitro-10 on egg yolk pigmentation.

White Leghorn hens, housed in cages were fed commercial-type corn-soy diets containing one of three levels of 3-Nitro-10 (0, .0025, and .005%) and either of two levels of xanthophyll (high and low) supplied by yellow corn. Egg yolks were collected and the yolks analyzed for color using reflectance colorimetry. The addition of 3-Nitro-10 at either level increased egg yolk dominant wavelength (DWL) and excitation purity (EP) values while decreasing luminosity (LUM) values (probability levels: .08, .10, and .003, respectively). It was concluded that the addition of 3-Nitro-10 to the diet of laying hens improved egg yolk color.

Animals↗

PubMed1987

Influence of caponization on skin pigmentation of male broilers.

Two experiments were conducted to investigate the influence of caponization on skin pigmentation. Male broiler chicks were divided into caponized, sham-operated, and intact treatment groups with surgery performed at 3 weeks of age (Experiment 1) or 1 week of age (Experiment 2). All chicks were provided with corn-soy broiler diets ad libitum. In Experiment 2, an additional 37.4 mg of total xanthophyll was added per kilogram of finisher diet. At 7 weeks of age, birds were processed, comb size was scored, and the gonadal area was examined to identify partially caponized or improperly sexed birds. Caponized, sham-operated, and intact carcasses for analysis totaled, respectively, 28, 25, and 18 in Experiment 1 and 59, 33, and 30 in Experiment 2. Skin pigmentation was measured by reflectance colorimetry on the anterior portion of the lateral feather tract, on the same area of breast skin after removal from the carcass, and on shank skin removed from the leg. No differences were found in skin lightness (L), redness (a), or yellowness (b) between the treatment groups. These results indicate that pigmentation differences between male and female broilers are not likely to be due to differences in testicular activity.

Animals↗

PubMed2005

Anti-HBV activity of TRL mediated by recombinant adenovirus.

AIM: To investigate the inhibitive effect of hepatitis B virus (HBV)-TRL on HBV replication. METHODS: Based on previously constructed pcDNA3.1(-)/TRL, TR, TRmut, HBV core protein (HBVc) and hEDN, interest gene sequences TRL, TR, HBVc and hEDN were inserted into adenovirus shuttle plasmid pDC316 respectively and co-transfected HEK293 cells with rescue plasmid pBHGloxdeltaE1,3Cre to acquire RAd/TRL, TR, HBVc and hEDN. And then RAds were identified, amplified and the titers in HEK293 cells were determined. RAd/TRL and TR were named as the experimental groups, and others were control ones. After HepG2.2.15 cells were infected, RAd/TRL expression was identified by indirect immunofluorescence staining. Supernatant HBV-DNA content was determined by fluorescent quantification PCR. Meanwhile, metabolism of HepG2.2.15 cells was evaluated by MTT colorimetry. RESULTS: RAd vectors with distinct interest gene sequence were successfully constructed. Effective expression of RAd/TRL in HepG2.2.15 cells resulted in a significant decrease of supernatant HBV-DNA content compared to RAd/TR (0.63+/-0.14 vs 1.60+/-0.47, P = 0.0266, <0.05) and other control groups (0.63+/-0.14 vs 8.50+/-2.78, 8.25+/-2.26, 8.25+/-2.29, 8.50+/-1.51, 8.57+/-1.63, P<0.01). MTT assay suggested that there were no significant differences in cell metabolic activity between groups (P>0.05). CONCLUSION: The construction and expression of RAd/TRL has been achieved and it could inhibit HBV replication successfully, which has laid the foundation for further research on anti-HBV activity in vivo.

Adenoviridae↗

PubMed2005

Anti-lipid peroxidation and protection of liver mitochondria against injuries by picroside II.

AIM: To investigate the anti-lipid peroxidation and protection of liver mitochondria against injuries in mice with liver damage by picroside II. METHODS: Three animal models of liver damage induced by carbon tetrachloride (CCl(4): 0.1 mL/10 g, ip), D-galactosamine (D-GalN: 500 mg/kg, ip) and acetaminophen (AP: 0.15 g/kg, ip) were respectively treated with various concentrations of picroside II (5, 10, 20 mg/kg, ig). Then we chose the continuously monitoring method (recommended by International Clinical Chemistry League) to analyze serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) values, Marland method to detect the activity of manganese-superoxide dismutase (SOD) in liver mitochondria, TBA colorimetry to determine the content of malonicdialdehyde (MDA) in liver tissue, DTNB method to evaluate the activity of glutathioneperoxidase (GSH-Px) and Lowry method to detect protein level in liver tissue. Meanwhile, effects of picroside II on the activity of ATPase and swelling extent of mitochondria in hepatocytes damaged by AP were also evaluated. RESULTS: Picroside II could significantly prevent liver toxicity in the three models of liver damage. It decreased the high levels of ALT and AST in serum induced by the administration of CCl(4), D-GalN and AP, reduced the cellular damage of liver markedly, and appeared to be even more potent than the positive control drug of biphenyl dimethyl dicarboxylate pilules (DDB). In groups treated with different doses of picroside II, compared to the model group, the content of MDA in serum decreased evidently, whereas the content of SOD and GSH-Px increased in a dose-dependent manner, and the difference was statistically significant. Further, in the study of AP model, picroside II inhibited AP-induced liver toxicity in mice, enhanced the activity of ATPase, improved the swelling extent of mitochondria and helped to maintain a normal balance of energy metabolism. CONCLUSION: Picroside II can evidently relieve hepatocyte injuries induced by CCl(4), D-GalN and AP, help scavenge free radicals, protect normal constructions of mitochondria membrane and enhance the activity of ATPase in mitochondria, thereby modulating the balance of liver energy metabolism, which might be part of the mechanisms of hepatoprotective effects of picroside II.

Animals↗

PubMed2005

VP22 fusion protein-based dominant negative mutant can inhibit hepatitis B virus replication.

AIM: To investigate the inhibitory effect of VP22 fusion protein-based dominant negative (DN) mutant on Hepatitis Bvrus (HBV) replication. METHODS: Full-length or truncated fragment of VP22 was fused to C terminal of HBV core protein (HBc), and subcloned into pcDNA3.1 (-) vector, yielding eukaryotic expression plasmids of DN mutant. After transfection into HepG2.2.15 cells, the expression of DN mutant was identified by immunofluorescence staining. The inhibitory effect of DN mutant on HBV replication was indexed as the supernatant HBsAg concentration determined by RIA and HBV-DNA content by fluorescent quantification-PCR (FQ-PCR).Meanwhile, metabolism of HepG2.2.15 cells was evaluated by MTT colorimetry. RESULTS: VP22-based DN mutants and its truncated fragment were expressed in HepG2.2.15 cells, and had no toxic effect on host cells. DN mutants could inhibit HBV replication and the transduction ability of mutant-bearing protein had a stronger inhibitory effect on HBV replication. DN mutants with full length of VP22 had the strongest inhibitory effect on HBV replication, reducing the HBsAg concentration by 81.94%, and the HBV-DNA content by 72.30%. MTT assay suggested that there were no significant differences in cell metabolic activity between the groups. CONCLUSION: VP22-based DN mutant can inhibit HBV replication effectively.

Carcinoma, Hepatocellular↗

PubMed2005

Selection of optimal antisense accessible sites of survivin and its application in treatment of gastric cancer.

AIM: To select the optimal antisense accessible sites of survivin, a highly expressed gene in tumor tissues, in order to explore a novel approach to improve biological therapy of gastric cancer. METHODS: The 20 mer random oligonucleotide library was synthesized, hybridized with in vitro transcribed total survivin cRNA, then digested by RNase H. After primer extension and autoradiography, the antisense accessible sites (AAS) of survivin were selected. Then RNADraw software was used to analyze and choose the AAS with obvious stem-loop structures, according to which the complementary antisense oligonucleotides (AS-ODNs) were synthesized and transferred into survivin highly- expressing gastric cancer cell line MKN-45. Survivin expression was detected by RT-PCR and Western Blotting. Cellular growth activities were assayed by tetrazolium bromide (MTT) colorimetry. Cellular ultrastructure was observed by electronic microscopy, while apoptosis was detected by annexin V-FITC and propidium iodide staining flow cytometry. RESULTS: Thirteen AAS of survivin were selected in vitro. Four AAS with stem-loop structures were chosen, locating at 207-226 bp, 187-206 bp, 126-145 bp and 44-63 bp of survivin cDNA respectively. When compared with non-tranfection controls, their corresponding AS-ODNs (AS-ODN(1), AS-ODN(2), AS-ODN(3) and AS-ODN(4)) could reduce Survivin mRNA levels in MKN-45 cells by 54.3+/-1.1% (t = 6.12, P<0.01), 86.1+/-1.0% (t = 5.27, P<0.01), 32.2+/-1.3% (t = 7.34, P<0.01) and 56.2+/-0.9% (t = 6.45, P<0.01) respectively, while survivin protein levels were decreased by 42.2+/-2.5% (t = 6.26, P<0.01), 75.4+/-3.1% (t = 7.11, P<0.01), 28.3+/-2.0% (t = 6.04, P<0.01) and 45.8+/-1.2% (t = 6.38, P<0.01) respectively. After transfection with 600 nmol/L AS-ODN1-AS-ODN(4) for 24 h, cell growth was inhibited by 28.12+/-1.54% (t = 7.62, P<0.01), 38.42+/-3.12% (t = 7.75, P<0.01), 21.46+/-2.63% (t = 5.94, P<0.01) and 32.12+/-1.77% (t = 6.17, P<0.01) respectively. Partial cancer cells presented the characteristic morphological changes of apoptosis, with apoptotic rates being 19.31+/-1.16% (t = 7.16, P<0.01), 29.24+/-1.94% (t = 8.15, P<0.01), 11.87+/-0.68% (t = 6.68, P<0.01) and 21.68+/-2.14% (t = 7.53, P<0.01) respectively. CONCLUSION: The AAS of survivin could be effectively selected in vitro by random oligonucleotide library/RNase H cleavage method combined with computer software analysis, this has important reference values for further studying survivin-targeted therapy strategies for gastric cancer.

Apoptosis↗

PubMed2002

Direct effect of croton oil on intestinal epithelial cells and colonic smooth muscle cells.

AIM: To investigate the direct effect of croton oil (CO) on human intestinal epithelial cell (HIEC) and guinea pig colonic smooth muscle cells in vitro. METHODS: Growth curves of HIEC were drawn by MTT colorimetry. The dynamics of cell proliferation was analyzed with flow cytometry, and morphological changes were observed under light and electron microscopy after long-term (6 weeks) treatment with CO. Expression of cyclooxygenase-2 (COX-2) mRNA was detected by dot blot in HIEC treated with CO. Genes related to CO were screened by DD-PCR, and the direct effect of CO on the contractility of isolated guinea pig colonic smooth muscle cells was observed. RESULTS: High concentration (20-40 mg x L(-1)) CO inhibited cell growth significantly (1, 3, 5, 7d OD sequence: (20 mg x L(-1)) 0.040+/-0.003, 0.081+/-0.012, 0.147+/-0.022,0.024+/-0.016; (40 mg x L(-1)) 0.033+/-0.044, 0.056+/-0.012, 0.104+/-0.010, 0.189+/-0.006; OD control 0.031+/-0.008, 0.096+/-0.012, 0.173+/-0.009, 0.300+/-0.016, P<0.01), which appeared to be related directly to the dosage. Compared with the control, the fraction number of cells in G1 phase decreased from 0.60 to 0.58, while that in S phase increased from 0.30 to 0.34 and DNA index also increased after 6 weeks of treatment with CO (the dosage was increased gradually from 4 to 40 mg x L(-1)). Light microscopic observation revealed that cells had karyomegaly, less plasma and karyoplasm lopsidedness. Electron microscopy also showed an increase in cell proliferation and in the quantity of abnormal nuclei with pathologic mitosis. Expression of COX-2 mRNA decreased significantly in HIEC treated with CO. Thirteen differential cDNA fragments were cloned from HIEC treated with CO, one of which was 100 percent homologous with human mitochondrial cytochrome C oxidase subunit II. The length of isolated guinea pig colonic smooth muscle cells was significantly shortened after treatment with CO (P<0.05). CONCLUSION: At a high CO concentration (>20 mg x L(-1)), cell growth and proliferation are inhibited in a dosage-dependent manner. Increase in cell proliferation and in malignant conversion of the cellular phenotype is observed in cells cultured chronically with CO. COX-2 mRNA expression decreases significantly, while human mitochondrial cytochrome C oxidase subunit IImRNA expression increases significantly in HIEC treated with CO. CO also has a direct effect on the contractility of Guinea pig colonic smooth muscle cells.

Animals↗

PubMed2003

Inhibition of HBV targeted ribonuclease enhanced by introduction of linker.

AIM: To construct human eosinophil-derived neurotoxin(hEDN) and HBV core protein (HBVc) eukaryotic fusion expression vector with a linker (Gly(4)Ser) (3) between them to optimize the molecule folding, which will be used to inhibit HBV replication in vitro. METHODS: Previously constructed pcDNA3.1(-)/TR was used as a template. Linker sequence was synthesized and annealed to form dslinker, and cloned into pcDNA3.1(-)/TR to produce plasmid pcDNA3.1(-)/HBc-linker. Then the hEDN fragment was PCR amplified and inserted into pcDNA3.1(-)/HBc-linker to form pcDNA3.1(-)/TNL in which the effector molecule and the target molecule were separated by a linker sequence. pcDNA3.1(-)/TNL expression was identified by indirect immunofluorescence staining. Radioimmunoassay was used to analyse anti-HBV activity of pcDNA3.1(-)/TNL. Meanwhile, metabolism of cells was evaluated by MTT colorimetry. RESULTS: hEDN and HBVc eukaryotic fusion expression vector with a linker (Gly(4)Ser)(3) between them was successfully constructed. pcDNA3.1(-)/TNL was expressed in HepG2.2.15 cells efficiently. A significant decrease of HBsAg concentration from pcDNA3.1(-)/TNL transfectant was observed compared to pcDNA3.1(-)/TR (P=0.036, P<0.05). MTT assay suggested that there were no significant differences between groups (P=0.08, P>0.05). CONCLUSION: Linker introduction enhances the inhibitory effect of HBV targeted ribonuclease significantly.

Carcinoma, Hepatocellular↗