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PubMed2005

The effect of DNA labeling with the fluorescent dyes R110 and R6G on genotype analysis using capillary electrophoresis.

We investigated the mobility of DNA fragments labeled with the fluorescent dyes R110 and R6G, specifically for use in genotyping using capillary electrophoresis. Genomic DNA was isolated from blood, and a highly polymorphic region of the HLA-C gene was amplified by PCR with the use of either [F]-dNTP-[R110] or [F]-dNTP-[R6G]. Pre-diluted (30-fold) PCR products were mixed with formamide, denatured (at 95 degrees C for 2 min.), and rapidly cooled on ice before being subjected to electrophoresis. The results showed that the number and mobility of allele-specific DNA fragments were independent of the two dyes used. Both dyes were equally efficient at differentiating homozygous or heterozygous allelic presentation. An additional dye-specific peak of 132-base-pair mobility was observed with the use of [F]-dNTP-[R110]; it significantly impaired the resolution of one allele-specific peak. The electropherograms obtained with [F]-dNTP-[R6G] were free from any interfering peaks within the target region, thus the [R6G]-based procedure is more preferable for genotype analysis. As this procedure does not involve any post-PCR cleanup, it is simple, rapid and cost-effective.

Alleles↗
PubMed2005

[Quantitative analysis of Danshensu in Tongmai Oral Solution by HPLC].

OBJECTIVE: To establish a method by RP-HPLC for determination of content of Danshensu (3,4-hydroxybenzyl lacticacid) in Tongmai Oral Solution. METHODS: The samples were separated on an ODS column Hypersil C18 (10 microm, 4.6 mm x 200 mm) with the mobile phase 0. 5% acetic acid-methanol-dimethyl formamide (99:0.5:0.5). The flow rate was 1.2 ml/min, and the detection wavelength was set at 335nm. RESULTS: The average recovery of Danshensu was 98.31%, and RSD was 2. 11%. CONCLUSION: The method is efficient and accurate with a good repeatability and can be used for the quality control of Tongmai Oral Solution.

Chromatography, High Pressure Liquid↗
PubMed1992

Acrolein initiates rat urinary bladder carcinogenesis.

Acrolein, a reactive, alpha,beta-unsaturated aldehyde which is ubiquitous in the environment, forms DNA adducts, is mutagenic, and is teratogenic. However, studies have not indicated a carcinogenic effect in rodent bioassays. Since it is present in cigarette smoke and is the toxic metabolite of cyclophosphamide with respect to the urinary tract, we investigated the possibility that acrolein might have carcinogenic activity toward the rat urinary bladder. We also evaluated whether it possessed initiating and/or promoting activity. To evaluate initiating activity, acrolein was administered at a dose of 2 mg/kg i.p. twice a week for 6 weeks followed by uracil as 3% of the diet for 20 weeks and then control diet for 6 weeks. N-[4-(5-Nitro-2-furyl)-2-thiazolyl]formamide (FANFT) as 0.2% of the diet followed by uracil was used as a positive control, and a negative control group was administered solvent control (water) i.p. during the 6-week initiation period followed by uracil. Acrolein followed by uracil produced an incidence of 18 of 30 rats (60%) with papilloma compared to 8 of 30 rats (27%) treated with solvent control followed by uracil. FANFT followed by uracil produced an incidence of 70% carcinomas and 30% papillomas, clearly indicating that it is a much more potent initiating agent than acrolein. Acrolein for 6 weeks followed by control diet produced no tumors. To evaluate promoting activity, groups of rats were fed FANFT for 6 weeks followed by acrolein. Acrolein administered during the initial 6 weeks and continued for the second phase of the experiment (to evaluate complete carcinogenic activity) resulted in severe toxicity. Administration of acrolein had to be terminated after 21 weeks of the experiment. The animals were maintained for 53 weeks of the experiment without further chemical treatment, and there was no evidence of papilloma or carcinoma development. This study clearly indicates that acrolein has initiating activity for the urinary bladder when administered by i.p. injection to the male F344 rat, but toxicity precluded evaluation of its promoting or complete carcinogenic activity.

Acrolein↗
PubMed2005

[Study on the fluorescence spectra of 7-hydroxyquinoline in dimethyl sulfoxide solution].

7-hydroxyquinoline (7-HQ) is a kind of organic molecule with excited-state proton transfer (ESPT) effect. 7-HQ in ethanol solution causes ESPT reaction under the excitation of ultraviolet light. The fluorescence spectrum of the sample exhibits two bands. In contrast, 7-HQ in dimethyl sulfoxide (DMS) solution does not cause ESPT reaction. The fluorescence spectrum of the sample exhibits a single band. But after the sample was irradiated with a strong UV light, its fluorescence spectrum also exhibits two bands. This phenomenon is reported for the first time in the present paper, and its cause is investigated through the study on the absorption spectra and fluorescence spectra of 7-HQ in ethanol, dimethyl sulfoxide and N, N-dimethyl formamide solution. The conclusion is that the change in the fluorescence spectrum of 7-HQ in DMS solution is due to the fact that 7-HQ causes ESPT reaction which results from the photodecomposition of DMS and the product of water after the solution was irradiated with strong UV light.

Dimethyl Sulfoxide↗
PubMed1991

Whole-blood microassay for immunodetection of antigen specific cell mediated immunity using bromodeoxyuridine incorporation.

The study evaluates a novel version of the bromodeoxyuridine (BrdU) incorporation assay for in vitro proliferative responses, which works with finger-prick blood specimens. It was developed primarily for field-work involving children in Africa and elsewhere. Heparinized blood specimens from healthy volunteers were diluted 1:15 and cultured with purified protein derivative, tetanus toxoid, concanavalin A or medium alone for four-seven days and pulsed during the last 24 hours with bromodeoxyuridine. Thereafter, white and red cells were separated by Ficoll-Pacque centrifugation. The white cells were made to adhere to Multitest slides pre-treated with poly-L-lysin. After fixation with paraformaldehyde, the cells were incubated with mouse monoclonal antibodies to a surface marker for activated T cells (CD25, interleukin-2 receptor) and the reaction visualized with anti-mouse alkaline phosphatase conjugated antibodies and a Fast Red substrate. After treatment with cold acetone, the cells were covered with formamide and heated to 70 degrees C, without loss of surface staining. The incorporation of bromodeoxyuridine was visualized in the UV-microscope with mouse anti-bromodeoxyuridine monoclonal antibodies and a rabbit anti-mouse fluorescein conjugate. Both the surface staining and the nuclear fluorescence can be seen in UV-light and the cells be classified as single- or double-positive or negative. Parallel experiments on the same blood-sample from seven donors allowed for at least 42 paired comparisons between the proportion of BrdU positive cells and thymidine incorporation stimulation indices. The latter assay was carried out both in the conventional version and in a whole-blood micro-version. The rank order correlations were 0.84 and 0.91 respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Bromodeoxyuridine↗
PubMedDate not supplied

Characteristics of fresh gander semen and its susceptibility to cryopreservation in six generations derived from geese inseminated with frozen-thawed semen.

The paper summarises seven years experiments designed to determine the effect of continuous insemination with frozen-thawed semen on fresh semen quality and sperm susceptibility to freezing stress in succeeding generations. During course of experiments, semen was collected from 10-12 White Koluda ganders at the age of 8-9 months, then subjected to freezing and used after thawing for insemination of 10 geese in order to obtain the subsequent generation of males. Semen was diluted 1 to 0.5 (v/v) with EK diluent, equilibrated for 15 min at +4 degrees C, mixed with 6 percent (v/v) of dimethyl-formamide (DMF), frozen to temp. -140 degrees C at a rate 60 degree C per min and then transferred into liquid nitrogen container. Semen samples were thawed prior to insemination in a 60 degree C water-bath. It is difficult to conclude whether freezing stress affected the fresh semen quality, since average volume of SQF (index comprising ejaculate volume, sperm concentration and percentage of live normal cells) varied between generations from 19.3 to 56.2. Continuous goose reproduction by insemination with frozen-thawed semen resulted in significant increase (P less than 0.01) in spermatozoa resistance to cryoinjury in every subsequent generation. In the relation to adequate fresh semen the percentage of live morphologically intact spermatozoa which withstood freezing procedure increased from 27.2 in first generation to 74.4 in sixth generation.

Animals↗
PubMed2006

[The effect of surface free energy parameters of diamond-like carbon films deposited on medical polyethylene terephthalate on bacterial adhesion].

Diamond-like carbon (DLC) films were deposited by acetylene plasma immersion ion implantation-deposition (PIII-D) on biomedical polyethylene terephthalate (PET). The capacities of Staphylococcus aureus (SA), Staphylococcus epidermidis (SE), Escherichia coli (EC), Pseudomonas aeruginosa (PA) and Candida albicans (CA) for adhesion to PETs are quantitatively determined by the plate counting and Gamma-ray counting of 125I radio labeled bacteria in vitro. The results indicate that the capacities of five types of bacteria for adhesion to PETs are all suppressed by C2H2 PIII-D (P<0.05). The surface energy components of the various substrates and bacteria are calculated based on measurements in water, formamide and diiodomethane and Lifshitz-van del Waals/acid-base approach (LW-AB). The surface free energies obtained are used to calculate the interfacial free energies of adhesion (deltaF(adh)) of five kinds of bacteria on various substrates, and the results show that it is energetically unfavorable for bacterial adhesion to the DLC films already deposited on PET by C2H2 PIII-D.

Bacterial Adhesion↗
PubMed2006

[Effect of hyaluronic acid chitosan-based microemulsion on the permeability of blood brain barrier in mice].

AIM: To study the effect of hyaluronic acid chitosan-based microemulsion (HAC-ME) on the permeability of blood brain barrier( BBB) by using Evans blue (EB) as the indicator. METHODS: A formamide extraction-ultraviolet spectrophotometry method was employed to determine the concentrations of EB in each of the tissues. The in vivo distribution of HAC-ME groups containing EB in mice and the fluorescence intensity and diffusion domain of brain slices were all studied. RESULTS: Contrasting to the common microemulsion (ME), HAC-ME at the lower concentration of HAC (<5 mg x mL(-1)) could further improve the transporting of EB across the BBB while EB concentration in other tissues decreased, and Tmax was delayed about 30 min. CONCLUSION: HAC-ME could facilitate the transporting of EB across the BBB and it was concentration dependent. While the brain targeting absorptive capability of HAC-ME was enhanced.

Animals↗
PubMed1990

Influence of surrounding media on preservation of cell wall ultrastructure of Candida albicans revealed by low temperature scanning electron microscopy.

Influence of surrounding media on the surface structures of the cell wall of Candida albicans was discussed with respect to the preservation of ultrastructure during the specimen preparation for scanning electron microscopy. The fibrillar structure of the cell surface was distinctly identified by the rapid-freezing technique. It was difficult, however, to observe this structure by the conventional specimen preparation technique. The reason for the difference between these two preparation techniques was studied using a low temperature SEM. Through investigating the influence of each step of the conventional technique on the fibrillar structure, it was found that the fibrils were drastically deformed and disappeared during the dehydration step in ethanol above 80% in concentration. In order to study which physicochemical properties participated in this disappearance phenomenon, yeast cells were treated with various media: solutions in different pH ranges and at different salt concentrations, ionic solutions, surfactants, formamide, dimethyl sulfoxide, acetone and Fehling's solution. As a result, the fibrillar structure was found well preserved when the medium had an affinity for the constituent molecules of the fibrils. When without affinity, the fibrils suffered a remarkable deformation. The mechanism of this deformation is discussed in terms of molecular interaction of solute and solvent.

Candida albicans↗
PubMed1991

[Antitubercular agents. LIV. 3-Alkyl(or -alkyl) thio-2,5-pyrazindicarboxamides].

From 5-cyano-3-chloro-2-pyrazinecarboxamide) (II) hydrolysis in acid medium) yielded 3-chloro-2,5-pyrazinedicarboxamide (III), which in a reaction with sodium hydrogensulfide in dimethyl-formamide) yielded 3-mercapto-2,5-pyrazinedicarboxamide (IV). This compound through condensations with alkyl- and arylhalogenides in triethylamine) yielded 3-alkyl(or aryl) thio-2,5-pyrazinedicarboxamides of type I. The structure of compounds was confirmed by elemental analysis, IR and 1H NMR spectra. A microbiological evaluation was carried out; the antituberculous effect of these compounds is not higher than that of pyrazinamide.

Mycobacterium tuberculosis↗
PubMed1991

[Studies on reaction and antibacterial activity of 1-aryl-4-ethoxycarbonyl-5-amino-1,2,3-triazole with several electrophilic reagents].

Upon treatment of 1-aryl-4-ethoxycarbonyl-5-amino-1,2,3-triazoles (1) with excess acetic acid, acetic anhydride, acetyl chloride, benzoyl chloride, formamide, etc., fourteen new derivatives of 1 were obtained in good yields, such as, 1-H-4-ethoxycarbonyl-5-arylamino-1,2,3-triazoles (2b-d), 1-RCO-4-ethoxycarbonyl-5-arylamino-1,2,3-triazoles (3a-d), 1-aryl-4-ethoxycarbonyl-5-acetylamino-1,2,3-triazoles (4a-d) and 1-formoyl-4-ethoxycarbonyl-5-p-nitrophenylamino-1,2,3-triazole (5a), 1-benzoyl-4-ethoxycarbonyl-5-p-nitrophenylamino-1,2,3-triazoles (5b), 1-p-chlorobenzoyl-4-ethoxycarbonyl-5-p-nitrophenylamino-1,2,3-triazoles (5c). Some of them were rearrangement products. Structures of all heterocyclic compounds were identified by elemental analyses, IR, 1HNMR and MS. Inhibiting effects of some compounds on B. substilis, E. coli, E. aerogenes and S. aureus were also screened.

Anti-Bacterial Agents↗
PubMed1991

[Extravascular transfer of fluids and proteins induced by endothelin in the binephrectomized rat].

To test the possibility that endothelin affects extracellular fluid partition between plasma and interstitium, we compared the effects of endothelin and vehicule in euvolemic binephrectomized anesthetized rats by measuring changes in hematocrit and plasma protein concentration. Forty-five minutes infusion of endothelin (25 ng/kg/min) induced a progressive increase in blood pressure by 1.7 +/- 1.3, 6.8 +/- 1.5 and 12.1 +/- 2.1% at 15, 30 and 45 min respectively from a basal value of 99 +/- 5 mmHg. Hematocrit increased by 8.0 +/- 0.6% (p less than 0.001) after 45 min of infusion, while the vehicle had no significant effect (+ 1.7 +/- 0.7%). The same increase in hematocrit was observed in binephrectomized and splenectomized rats. The calculated loss of plasma volume during endothelin infusion was 13.1 +/- 0.9% as compared to 2.1 +/- 1.2% in rats receiving the vehicle. Plasma protein concentration increased by only 4.2 +/- 0.6% suggesting an extravasation of proteins. To document and localize an alteration in vascular leak of proteins induced by endothelin, albumin-bound Evans Blue (EB) extravasation was measured spectrophotometrically in different tissues after extraction by formamide. Endothelin increased vascular permeation of EB-albumin in skeletal and cardiac muscle, intestine and mesentery. No change was observed in brain, liver, spleen as compared to rats receiving the vehicle. In addition, endothelin infusion elicits a three fold increase of the plasma immunoreactive atrial natriuretic peptide (ir-ANP) concentration (from 196 +/- 50 to 722 +/- 203 pg/ml; p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Metabolism and disposition of bladder carcinogens in rat and guinea pig: possible mechanism of guinea pig resistance to bladder cancer.

The metabolism and disposition of N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) and 2-amino-4-(5-nitro-2-furyl)thiazole (ANFT) were studied in rat and guinea pig. Rat is susceptible whereas guinea pig is resistant to FANFT-induced bladder cancer. Rats and guinea pigs were p.o. administered either 2-[14C]ANFT or 2-[14C]FANFT (100 mg/kg), and 18-h urine and feces were collected. Tissue distribution of radiolabel was determined. In both species, the highest concentrations of radioactivity expressed as nmol/g tissue were observed in the urine and intestines. Urinary metabolites were separated by high-performance liquid chromatography and radioactivity determined by radioanalytical detection. FANFT was not detected in urine from either species under any experimental condition. More ANFT was observed in urine following FANFT than ANFT administration. This deformylation-dependent excretion of FANFT was demonstrated in both species and has been previously described as renal metabolic/excretory coupling. Less ANFT, the carcinogen more proximate than FANFT, is excreted in guinea pigs compared with rats. A unique ANFT metabolite was identified in guinea pig but not rat urine. This metabolite represented 80 and 18% of radioactivity recovered in guinea pig urine following ANFT and FANFT administration, respectively. A metabolite produced by guinea pig liver and kidney microsomes in the presence of uridine-5'-diphosphoglucuronic acid coeluted with this unique metabolite. The urinary metabolite was characterized using hydrolytic enzymes, acid hydrolysis, and mass spectrometry and identified as an ANFT-N-glucuronide. A unique UDP-glucuronosyl-transferase appears to be responsible, at least in part, for the reduced amount of free ANFT excreted by guinea pigs compared with rats. Reduced levels of urinary ANFT observed in guinea pigs may partially explain the resistance of this species to FANFT-induced bladder cancer.

Animals↗
PubMed1977

Comparison of the nucleotide sequence of the messenger RNA for the major structural protein of SV40 with the DNA sequence encoding the amino acids of the protein.

The 16S late mRNA from SV40 directs the synthesis of the major viral structural protein, VP1. We have compared the oligonucleotides in the 16S mRNA with those that would be present in a transcript of the portion of SV40 DNA coding for VP1. The results indicate that a segment of about 200 nucleotides of RNA transcribed from a distant part of SV40 DNA have become linked to the transcript of VP1 codons by a bond resistant to phenol extraction and denaturation in formamide.

Base Sequence↗
PubMed1991

Comparative bladder tumor promoting activity of sodium saccharin, sodium ascorbate, related acids, and calcium salts in rats.

Sodium saccharin and sodium ascorbate are known to promote urinary bladder carcinogenesis in rats following initiation with N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) or N-butyl-N-(4-hydroxybutyl) nitrosamine. Sodium salts of other organic acids have also been shown to be bladder tumor promoters. In addition, these substances increase urothelial proliferation in short term assays in rats when fed at high doses. When they have been tested, the acid forms of these salts are without either promoting or cell proliferative inducing activity. The following experiment was designed to compare the tumor promoting activity of various forms of saccharin and to evaluate the role in promotion of urinary sodium, calcium, and pH as well as other factors. Twenty groups of 40 male F344 rats, 5 weeks of age, were fed either FANFT or control diet during a 6-week initiation phase followed by feeding of a test compound for 72 weeks in the second phase. The chemicals were administered to the first 18 groups in Agway Prolab 3200 diet and the last 2 groups were fed NIH-07 diet. The treatments were as follows: (a) FANFT----5% sodium saccharin (NaS); (b) FANFT----3% NaS; (c) FANFT----5.2% calcium saccharin (CaS); (d) FANFT----3.12% CaS; (e) FANFT----4.21% acid saccharin (S); (f) FANFT----2.53% S; (g) FANFT----5% sodium ascorbate; (h) FANFT----4.44% ascorbic acid; (i) FANFT----5% NaS plus 1.15% CaCO3; (j) FANFT----5.2% CaS plus 1.34% NaCl; (k) FANFT----5% NaS plus 1.23% NH4Cl; (l) FANFT----1.15% CaCO3; (m) FANFT----1.34% NaCl; (n) FANFT----control; (o) control----5% NaS; (p) control----5.2% CaS; (q) control----4.21% S; (r) Control----control; (s) FANFT----5% NaS (NIH-07 diet); (t) FANFT----control (NIH-07 diet). NaS, CaS and S without prior FANFT administration were without tumorigenic activity. NaS was found to have tumor promoting activity, showing a positive response at the 5 and 3% dose levels, with significantly greater activity at the higher dose. CaS had slight tumor promoting activity but without a dose response, and S showed no tumor promoting activity. In addition, NaCl showed weak tumor promoting activity, but CaCO3 was without activity. NH4Cl completely inhibited the tumor promoting activity of NaS when concurrently administered with it. NaCl administered with CaS or CaCO3 administered with NaS showed activity similar to that of NaS. Sodium ascorbate was also shown to have tumor promoting activity, with slightly less activity than NaS. Ascorbic acid showed no tumor promoting activity.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1991

Lack of bladder tumor promoting activity in rats fed sodium saccharin in AIN-76A diet.

Sodium saccharin (NaSac) fed as 5% of Prolab diet promotes bladder tumor carcinogenesis in male F344 rats initiated with N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) fed as 0.2% of the diet for 4 weeks. NaSac also increases urothelial proliferation if fed for short periods in Prolab diet, but no increased proliferation is seen if it is fed for up to 10 weeks in AIN-76A semisynthetic diet, even at levels as high as 7.5% of the diet. To determine whether NaSac as part of an AIN-76A diet has promoting activity, groups of approximately 30 male, 5-week-old F344 rats were fed AIN-76A diet containing (a) 0.2% FANFT for 4 weeks followed by 5% NaSac for 100 weeks; (b) 0.2% FANFT followed by control diet; or (c) control diet followed by 5% NaSac. Bladder tumor incidences were 10, 23, and 0%, respectively. When fed in Prolab diet, 0.2% FANFT for 4 weeks followed by NaSac or control diet for 100 weeks resulted in bladder tumor incidences of 40 and 17%, respectively. Groups of rats fed 0.1 or 0.2% FANFT for 1 or 2 weeks followed by 5% NaSac or control diet for 100 weeks had bladder tumor incidences of 0 to 7%. These data demonstrate that NaSac does not promote bladder cancer in male rats if fed in AIN-76A diet. Other studies suggest that this is due to the low urinary pH in rats fed AIN-76A diet.

Animals↗
PubMed1978

Identification of a high molecular weight presumptive precursor to albumin mRNA in the nucleus of rat liver and hepatoma cell line H4AZC2.

Nuclear RNAs prepared from rat liver and rat hepatoma cell line H4AZC2 have been fractionated and examined for albumin mRNA sequences by annealing to specific albumin [3H]cDNA. In both instances, sucrose gradient analysis revealed nuclear RNA molecules containing albumin RNA sequences which sedimented at 26 S (26 S albumin RNA). In contrast, cytoplasmic albumin messenger RNA sediments exclusively at 17 S. 26 S albumin RNA is resistant to both heat denaturation (65 degrees C X 5 min) and denaturation in 85% formamide (v/v), and 75% of these molecules are polyadenylated. These results provide evidence for the existence of an intact, high molecular weight, polyadenylated nuclear RNA which contains albumin mRNA sequences.

Animals↗
PubMed1978

A comparison of polysomal messenger ribonucleoprotein particles from normal and neoplastic rat liver.

Free polysomes were isolated from normal and regenerating rat liver and from Morris hepatomas 7777, 7800, 5123C and 9618A. Sucrose gradient analysis ruled out the possibility of any significant messenger RNA degradation in these polysome preparations. The ethylenediaminetetraacetate-disrupted polysomes were fractionated on oligodeoxythymidylic acid-cellulose columns. The column-bound polyriboadenylic acid-containing messenger ribonucleoprotein particles were eluted with a formamide buffer, precipitated with ethanol, and subjected to polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The messenger RNA-associated proteins from the different tissues were qualitatively similar, but two proteins with molecular weights of 66,000 and 109,000 found as minor proteins in normal liver appeared on gels as major protein bands when hepatoma messenger ribonucleoprotein particles were examined. The 66,000- and 109,000-molecular-weight proteins in these particles from regenerating liver appeared quantitatively similar to those isolated from normal liver.

Animals↗