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At least 847 records · Page 47Linked to original sources

PubMed1998

[Effects of IL-1 and TNF-alpha on the proliferation and cytosolic Ca2+ of lens epithelial cell in vitro].

OBJECTIVE: To study the effects of interleukin 1 (IL-1) and tumor necrosis factor alpha (TNF-alpha) on the proliferation and cytosolic Ca(2+) of bovine lens epithelial cells (BLEC) in vitro. The effects of IL-1 and TNF-alpha on posterior capsular opacification (PCO) and the mechanism of effect on the proliferation were investigated. METHODS: The effects of IL-1 and TNF-alpha on the proliferation of BLEC were detected with MTT staining colorimetry, and cytosolic Ca(2+) was measured by fluorescence determination with Fura-2. RESULTS: IL-1 10(2) - 10(5) ng/ml, TNF-alpha 10(2) - 10(4) U/ml obviously could promote BLEC proliferation (P < 0.05 - 0.01), and increase cytosolic Ca(2+) (P < 0.05 - 0.01) at the same doses. CONCLUSIONS: IL-1, TNF-alpha contribute to the PCO. One of the mechanisms of IL-1 and TNF-alpha on proliferation is by cytosolic Ca(2+).

Animals↗

PubMedDate not supplied

Capnography: beyond the numbers.

Detecting end-tidal pressure of carbon dioxide (PetCO2) is becoming increasingly common in the emergency transport setting. Several CO2 detection devices are suitable for emergency transport, including colorimetry, capnometry, and capnography. Capnography is the only device that displays a waveform of CO2 levels throughout the respiratory cycle. Analysis of this waveform is key to avoiding therapeutic errors. End-tidal PCO2 is best used for verifying endotracheal and nasal gastric tube placement and assessing the effectiveness of CPR. The use of capnography as a means of guiding manual or mechanical ventilatory therapy is unreliable in unstable, critically ill, or injured patients.

Capnography↗

PubMed2002

Caspase activation and amyloid precursor protein cleavage in rat ocular hypertension.

PURPOSE: Retinal ganglion cell (RGC) death in glaucoma involves apoptosis. Activation of caspases and abnormal processing of amyloid precursor protein (APP) are important events in other chronic neurodegenerations, such as Alzheimer's disease (AD). The retinal expression and activation of caspases and the patterns of caspase-3-mediated APP processing in ocular hypertensive models of rat glaucoma were investigated. METHODS: RGC death was produced in one eye by chronic exposure to increased intraocular pressure (IOP) or by optic nerve transection. Elevated IOP was produced by obstruction of aqueous humor outflow with laser coagulation or limbal hypertonic saline injection. Caspase activity and APP processing in the retina were examined by RNase protection assay (RPA), immunocytochemistry, immunoblot assay, and colorimetric assay. RESULTS: RPA revealed elevations of caspase-3 mRNA, as well as other apoptosis-related mRNAs. Immunocytochemistry showed caspase-3 activation in RGCs damaged by ocular hypertension. The generation of the caspase-3-mediated APP cleavage product (DeltaC-APP) was also increased in ocular hypertensive RGCs. Western immunoblot assay and colorimetry revealed significantly more activated caspase-3 in ocular hypertensive retinas than in control retinas. The activated form of caspase-8, an initiator caspase, and amyloid-beta, a product of APP proteolysis and a component of senile plaques in AD, were detected in RGCs by immunohistochemistry significantly more often in ocular hypertensive than in control retinas. The amounts of full-length APP were reduced and amyloid-beta-containing fragments were increased in ocular hypertensive retinas by Western immunoblot assay. CONCLUSIONS: Rat RGCs subjected to chronic ocular hypertension demonstrate caspase activation and abnormal processing of APP, which may contribute to the pathophysiology of glaucoma.

Amyloid beta-Peptides↗

PubMed2001

Towards versatile metal associating substrates for the determination of peroxidatic activity/hydrogen peroxide by chemical designing of Schiff base derivatives.

Novel chromogenic N-arylmethyl-aniline-substrates of the general formula R-NH-CH2C6H5-n-Xn (X = OH, NHR) for the localization of peroxidatic activity/hydrogen peroxide were synthesized in two steps from starting amines and aromatic aldehydes. When using 1,2-dinucleophiles (e.g. diaminobenzidine) as starting material there may be limitations resulting from dominant altemative reaction courses (amino-imines vs bis-imines) or tautomerism (amino-imines vs benzimidazolines). This has been investigated in a model study on 1,2-phenylendiamine. All substrates were evaluated for application in histochemistry, electrophoresis, colorimetry and electron microscopy. Thus, 1/ endogenous peroxidatic activity in native cryotome sections of Wistar rats was stained. One selected reagent was used for immuno-histochemical demonstration of vimentine and applied for laser microscopy at 543 nm as well. 2/ Electro-blotted dilution series of horseradish peroxidase were stained and reagents ranked according to their sensitivity. 3/ In test tube experiments precipitation behavior, color and solubility of precipitates was investigated. 4/The chromogens are capable of forming electron opaque final reaction products by way of increased osmiophilicity of the specific reaction product or/and by complexation of electron dense metals as demonstrated by electron microscopical investigations. As a result, two novel reagents derived from 1,2-phenylendiamine and 2-aminophenol are recommended especially for electron microscopy: The discrimination between internum and extemum of specific granules after osmium tetroxide treatment is resolved clearly as compared with results obtained with the standard Kamovsky protocol.

Animals↗

PubMed2000

[Effect of xiongshao capsule on proliferation and apoptosis of vascular smooth muscle cells in rabbits observed by serum pharmacological method].

OBJECTIVE: To observe the effect of Xiongshao Capsule (XSC) on proliferation and apoptosis of aortic smooth muscle cells (SMC) of rabbits by serum pharmacological method. METHODS: SMC were isolated from thoracic aorta of the normal rabbits and passaged. The SMC proliferation model was established by endothelin (ET). The medicated serum was prepared after given the normal rabbits suspension of XSC through gastrogavage for 10 days. The proliferation and apoptosis of SMC were observed by methyl thiazolyl tetrazolium (MTT) colorimetry, flow cytometry and agarose gel electrophoresis. RESULTS: ET obviously promoted proliferation of SMC, and the serum medicated with XSC could lower the proportion of SMC in S + G2 phase and markedly inhibited the proliferation of SMC caused by ET in dose dependent manner. It also had certain effect on inducing apoptosis of SMC. CONCLUSION: XSC could markedly inhibit the proliferation of SMC caused by ET and induce apoptosis of SMC, which might be the mechanism of preventing coronary restenosis after interventional treatment.

Animals↗

PubMed2002

[Long-term effect of nitric oxide synthase inhibitor on repair of articular cartilage defects repairing].

OBJECTIVE: To discuss the long-term effect of inducible nitric oxide synthase inhibitor S-methylisothiourea (SMT) on repair of articular cartilage defects. METHODS: Twenty-four adult New Zealand White rabbits with full-thickness defects of cartilage created in the trochlear groove of their bilateral femurs were divided into three groups randomly, 8 in each group: (1) control group in which nothing was filled into the defects; (2) BMP group in which the defects were filled with collagen fibrin gel impregnated with recombinant human bone morphogenic protein (rhBMP); and (3) SMT group in which the defects were filled with collagen fibrin gel impregnated with rhBMP and hypodermic injection of SMT (5 mg .(-1) 12 h(-1)) was given. The animals were killed one year later. The gross appearance of the defects was assessed. The amount of released NO and the activity of NOS were examined by chemical colorimetry. The distribution of collagen was examined by immunohistochemistry. The proteoglycan synthesis and cell activity was assessed by incorporation of radiolabelled sodium sulphate Na(2)(35)SO(4) and bromodeoxyuridine. RESULTS: One year after the defects in SMT group showed greater improvement in margin integration, cellular morphology, and architecture within defect than those in BMP group and control group (P < 0.01). Immunohistochemistry showed that there was less type-I collagen and more type-II collagen in SMT group than in the other two groups. Radiolabelled sodium sulphate (Na(2)(35)SO(4)) incorporation test showed that the proteoglycan synthesis in defects was higher in SMT group than in the other two groups (P < 0.01). BrdU incorporation test showed cells in repaired tissue with remarkable proliferous activity. CONCLUSION: iNOS inhibitor SMT significantly improves the quality of repair of defected cartilage and delays its degradation.

Animals↗

PubMed1999

[The comparison of component contents and pharmacological actions between two kinds of processed products of Pinellia rhizoma prepared by ginger juice and alum].

OBJECTIVE: To compare the component contents in Pinellia Rhizoma processed with ginger separately on orthogonal technology and pharmaceutical technology stipulated in pharmacopoeia, and study the action of the two differently processed products on animals. METHOD: Using gravimetric method and acid dye colorimetry to determine the total alkaloids, et al. RESULT AND CONCLUSION: The experiment has shown that the contents of total alkaloids of product of Pinellia Rhizoma processed by orthogonal technology are higher than those processed by pharmaceutical technology, but the contents of digged substances of the latter are higher than those of the former, and the toxicity of decoction of the latter is also higher than that of the former. Compared with raw Pinellia Rhizoma, the two products of Pinellia Rhizoma prepared by different technologies all have shown promoting action on PGE2 contents and activity of gastric proteinase in rat gastric juice. The experimental results also have shown that on the above mentioned items. There are no obvious differences between the product of Pinellia Rhizoma processed by orthogonal technology and the product processed by pharmaceutical technology. However, the component contents of raw Pinellia Rhizoma are lower than those of the above mentioned two processed products and help inhibit PGE2 contents and activity of gastric proteinase in rat gastric juice.

Alkaloids↗

PubMedDate not supplied

[Method of electrophoretic determination of S-methyl methionine in plants].

A method to determine S-methyl methionine (vitamin U) in plants has been devised. The method includes S-methyl methionine extraction extract purification on cationite KU-2 in the NH4+-form, S-methyl methionine eluation with 2n water solution of NH4OH from the cation exchange resin, eluate evaporation in vacuo, dissolution of the residue in a minimal amount of water acidified with hydrochloric acid, electrophoretic separation of S-methyl methionine from basic amino acids, ninhydrine development of the electrophoregram, methanol eluation of the spot corresponding to S-methyl methionine, and colorimetry of the solution at 506 mmu. Relative error is +/-2.5%.

Electrophoresis, Paper↗

PubMed2002

Stabilization of nontoxic PVC formulation for gamma irradiation sterilization, I. Effect of additives.

In order to investigate the fundamental data for the resistance of gamma radiation sterilization of polyvinylchloride (PVC), the formulations of the additives such as plasticizers of dioctylphthalate, trioctyltrimellitate and polyester, second plasticizers, Ca/Zn nontoxic metallic stabilizers with powder, paste and liquid state, and phosphite stabilizers have been carried out. The control and irradiated PVC samples with 1.5, 2.5 and 4.0 Mrads were characterized by mechanical tester, colorimetry, and extractant in water. The effect of plasticizers observed in the order of dioctylphthalate approximately equal trioctyltrimellitate > polymeric plasticizer. It was observed in the order of Ca/Zn metallic stabilizers of paste > liquid approximately equal powder state for the color change and liquid > paste > powder for the extractant. The mechanism of the discoloration of PVC in our experiment was predominant the formation of polyene by the dehydrochlorination rather than the formation of keton and aldehyde by the oxidation and chain dissociation by the measurement of gel permeation chromatography and mechanical property. The proposed mechanisms of stabilization and discolorization with various additives are also discussed.

Biocompatible Materials↗

PubMed1975

A column chromatography fractionation of the hydroxyproline-containing urinary peptides with continuous automatic detection.

Dialyzable and non-dialyzable urinary hydroxyproline-containing peptides are chromatographed respectively on QAE-Sephadex and on phosphocellulose. They are detected and quantitated by continuous hydrolysis in 3.3 N NaOH followed by oxidation by chloramine T and colorimetry with p-dimethylamino-benzaldehyde. The patterns of dialyzable urinary hypropeptides do not show significant qualitative differences between normal subjects and patients suffering from Paget's bone disease or cancer metastases of bone. The patterns of non-dialyzable urinary hypropeptides, show more variability in the case of normal subjects and differ more largely in the case of Paget's disease of bone.

Autoanalysis↗

PubMedDate not supplied

Bioavailability studies on fast release formulations of indomethacin.

Indomethacin-nicotinamide solid dispersions were prepared by fusion method. Drug-carrier interaction in the liquid and solid states were studied using phase solubility data and differential scanning colorimetry (DSC). DSC revealed the formation of an eutectic mixture of indomethacin and nicotinamide. Tablets and capsules, formulated from the solid dispersions showed significantly better dissolution and enhanced absorption rate in human volunteers, compared to commercial capsule of indomethacin.

Adult↗

PubMed2002

[In vitro selection and affinity function of the aptamers to Bacillus anthracis spores by SELEX].

To obtain oligonucleotide aptamers, specifically binding to Bacillus anthracis spores, and to find the relationship between the structures and the affinities, and to determine whether the aptamers can be used as a novel molecule for spore detection, a synthetic 35 mer random DNA library was subjected to 18 rounds of selection by using SELEX (systematic evolution of ligands by exponential enrichment) protocol against spores of Bacillus anthracis vaccine strain A. 16R. The selected aptamers were cloned and sequenced. Software packages CLUSTALX (1.8) and DNASIS v2.5 were employed to analyze the conserved sequences and second structures of the aptamers, respectively. Affinities of aptamers to the spores were visualized by biotin streptavidin horseradish peroxidase system. DAB was used to visualize signals, as an assay method. A membrane-based hybrid sandwich assay was developed for detecting Bacillus anthracic spores by using a 5'-biotinylated ssDNA aptamers and anti-spore antibodies. PCR amplification band pattern of the first round selection was different from that of the ninth round. The binding assay demonstrated that the affinity of the eighteenth round pool increased thirty-seven folds more than that of the first round pool. The affinities of the aptamers were different: the highest A at 450 nm was 1.20, and the lowest was 0.20. The secondary structure analysis revealed possible stem-loop and hairpin structures for binding to the spores. The colorimetry on the immuno-membrane got the best signal with a ratio of 16 microgram aptamer to 4x10(7) spores. A set of aptamers with considerable binding affinity to Bacillus anthracis spores was successfully selected from the initial random ssDNA pool. The stem-loop and hairpin at 5' end of the aptamers worked as the main motif in the interaction between oligonucleotides and spores, while the neighbor bases of the triple structure might affect the stability. Therefore ssDNA aptamers seem to be a type of potential diagnostic molecule.

Bacillus anthracis↗

PubMed1999

[Studies on the stability of sodium taurocholate in different media and in the course of sterilization].

OBJECTIVE: To investigate the stability of the main active constituent of snake gall sodium taurocholate, TCANa in 25% alcoholic solution and artificial gastric juice, and in the course of hot pressurized sterilization. METHOD: The stability of the solution was predicted by an accelerated isothermal test, and the content of TCANa was determined by TLC-colorimetry. RESULT: The half-time(t1/2) of TCANa in 25% alcoholic solution is 60.57 d at 25 degrees C, and in artificial gastric juice 11.37 d at 37 degrees C, the loss rate under the condition(115 degrees C, 30 min) of sterilization about 3%. CONCLUSION: TCANa in 25% alcoholic solution is unstable. Therefore it is suggested that in order to raise the stability of TCANa the alcoholic concentration be increased and the solution be stored at temperatures below 0 degree C.

Animals↗

PubMed1975

[Determination of methyl parathion (0.0-dimethyl-(p-nitrophenyl)-thiophosphoric acid ester) and metabolites in animal material and in feed].

A new thin-layer chromatography method was developed to detect parathion-methyl (0.0-dimethyl-0-p-nitrophenyl phosphorothioate) and its metabolite methyl-paraoxon and the degradation produce p-nitrophenol in samples of animal and plant origin. Coupling with Bratton-Marshall reagent, as used in colorimetry, was employed to detect the compounds on the chromatography plate. Pretreatment of the samples was simplified by preparing a crude extract and separating unwanted substances from the pesticide compounds by thin-layer chromatography.

Animals↗

PubMedDate not supplied

Comparison of visual immunoassay and chromogenic culture medium for the presence of Listeria spp. in foods.

Two rapid screening methods [the TECRA Listeria Visual Immunoassay (LIS-VIS) kit, an AOAC-approved 48 h visual test, which detects Listeria through colorimetry, and BCM Listeria isolation and differentiation plating agar] were used to screen U.S. Food and Drug Administration-regulated commodities for the presence of Listeria spp. Seventy-four different food samples were screened for the presence of Listeria spp. by using both protocols. Test results for the TECRA LIS-VIA showed 66 negative samples and 1 false positive, with 4 confirmed as L. monocytogenes and 3 as L. innocua. With the BCM agar, 67 samples were negative, 4 were confirmed as L. monocytogenes, and 3 were confirmed as L. innocua. Both methods showed similar results and were effective screening tools for Listeria spp. in foods. The BCM agar method proved to be a rapid, sensitive, and excellent tool for early screening and differentiation of Listeria spp. present in foods.

Coloring Agents↗

PubMed1999

Effects of high temperature and noise on erythrocyte membrane ATPase activity in pilots during flight.

Objective. To determine the effect of heat and noise on erythrocyte membrane ATPase activities in pilots during flying. Method. Twenty-four pilots performing bombing for 3 h (45-53 degrees C, 122-97 dB in the cabin) served as the subjects. 21 ground personnel served as control (27 degrees C in the room). Blood samples were taken from both groups before flying (6:00 a.m.), and immediately (12:00 a.m.) and 8 h (8:00 p.m.) after flying. Na(+)-K+ ATPase, and Ca2(+)-Mg2+ ATPase activities in erythrocyte membrane were determined with colorimetry. Result. The Na(+)-K+ ATPase activity in erythrocyte membrane at 6:00 a.m. in pilots was higher than that in control group at the same time (P<0.01). The Ca2(+)-Mg2+ ATPase activities in erythrocyte membrane at 12:00 a.m. and 8:00 p.m. in pilots were significantly higher, compared with those in control group at the same time (P<0.01). Conclusion. The ATPase values obtained in our study were all within normal range, and the daytime variation of both groups are the same. Exposure of human body to heat and noise for long time may be harmful, the higher ATPase activity is, the more catabolism of ATP will be. ATP exhaustion will lead to Ca2+ overload in erythrocyte thus stiffen the red cell membrane.

Adult↗

PubMed2002

Stabilization of nontoxic PVC formulation for gamma irradiation sterilization, II. Effect of antioxidants.

In order to investigate the fundamental data for the resistance of gamma radiation sterilization of polyvinylchloride (PVC), the formulations of the antioxidants such as commercial Irganox series and inorganic, processing aids, stabilizer aids, trans-stilbene oxide (StO) and so on have been carried out. The control and irradiated PVC samples with 1.5, 2.5 and 4.0 Mrad were characterized by mechanical tester, colorimetry, and extractant in water. Irganox 1010 was more effective than Irganox 1076 for color changes whereas Irganox 1076 was more effective than Irganox 1010 for the change of extractant. It was also observed the significant diminution of color changes for inorganic antioxidants as CaO and ZnO. Oxidized paraffin wax as lubricant, styrene-methylmetacrylate copolymers as processing aids, and nontoxic debenzoylmethane as secondary stabilizer did not show good stabilization for the irradiation. The new proposed radiation stabilizer in this study, StO, showed the significant improvement of gamma radiation resistance for the plasticized PVC. The possible mechanism could be explained that an epoxy functional group stabilizes effectively the processes of dehydrogenation, the formation of hydroperoxides, and the formation of oxygen containing groups, and the synergetic effects of an epoxy compound are more notable for the prevention of radiation oxidation in the presence of an aromatic group.

Antioxidants↗

PubMed2002

[Relationship between vaginal sialidase bacteria vaginosis and chorioammionitis].

OBJECTIVE: To study the relationship among vaginal sialidase, bacterial vaginosis (BV), chorioammionitis and subsequent adverse outcome of pregnancy. METHODS: Vaginal sialidase was measured by colorimetry in samples of vaginal discharges from 80 pregnant women with BV (study group) and 60 normal pregnant women at same gestation weeks (control group). Color turning blue means positive of sialidase activity, and no color changing means negative. The diagnosis of chorioammionitis was based on pathological examination. RESULTS: Ninety six dot three percent, 3.3% exhibited sialidase activities in study group and control group, respectively. There were significant differences between these two groups (P < 0.001). By measuring vaginal sialidase activity, the sensitivity, specificity, positive and negative predictive value in diagnosing BV were 96.3%, 96.7%, 97.5% and 95.1%, respectively. Chorioammionitis, premature rupture of membranes, premature delivery and puerperal infection in sialidase positive group were significantly higher than the negative group. Sensitivity, specialty of sialidase activity for chorioammionitis were 87.5%, 50.0%, respectively. CONCLUSION: Vaginal sialidase activity has strong relation with bacterial vaginosis. Measuring vaginal sialidase activity is a fast, easy, and useful method to diagnose bacterial vaginosis. It also has relation with chorioammionitis and subsequent adverse outcome of pregnancy.

Chorioamnionitis↗