SEARCH · PubMed Health

Results for “Colorimetry”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 883 records · Page 49Linked to original sources

PubMed2003

[Oxidative stress status in patients with various degrees of chronic renal insufficiency].

OBJECTIVE: To observe the changes of lipid peroxidation and antioxidative enzyme activities of chronic renal insufficiency (CRI) and to explore their effects on the pathogenesis of CRI. METHODS: Serum levels of malondialdehyde (MDA), serum glutathione peroxidase (GSH-Px) and serum superoxide dismutase (SOD) in 36 non-dialyzed patients with various degrees and 12 hemodialyzed (HD) were determined with the method of chemistry colorimetry. RESULTS: Thirty-six CRI and 12 HD patients included in the study had higher SOD activities when compared with the controls [(110.30+/-18.60) kNU/L]. They also had lower serum GSH-Px activity than the controls [(120.63+/-27.57) x 10(4)U/L]. Serum MDA levels in the patients were higher than that in the controls [(4.06+/-0.67) micromol/L]. Serum SOD, GSH-Px and MDA concentrations in 36 non-dialyzed patients with various degrees were also correlated with creatinine clearance (r(G)=0.68, P<0.01; r(M)=-0.52, P<0.01; r(S)=-0.44, P<0.05). CONCLUSION: Free radicals, lipid peroxidation and the abnormality in antioxidative system may play an important role in the pathogenesis of CRI and correlated with impaired renal function, and that they can be regarded as important clinical indexes to infect the severity of chronic renal insufficiency.

Adolescent↗

PubMed2003

[Effect of severe thoracic trauma combined with endotoxin challenge on phagocytosis function of alveolar macrophages and pulmonary interstitial macrophages].

OBJECTIVE: To observe the difference of phagocytosis between alveolar macrophages and pulmonary interstitial macrophages, and to investigate their responses to severe thoracic trauma with or without lipopolysaccharide (LPS) challenge. METHODS: A rat model of severe thoracic trauma was reproduced by thoracic impact machine. The alveolar macrophages and interstitial macrophages were isolated before injury and at 2, 4, 8, 16, 24 hours after injury respectively. The dynamic changes of these macrophage phagocytosis were tested by malachite green colorimetry. RESULTS: Macrophage phagocytosis function was increased during the early stage after trauma (2 and 4 hours) and then decreased. The phagocytosis function of alveolar macrophages was stronger than that of interstitial macrophages in all time points before and after trauma. After challenge with LPS, no further significant effect on the alveolar macrophages was found, while LPS challenge could stimulate the phagocytosis of interstitial macrophages. CONCLUSION: Alveolar macrophages and pulmonary interstitial macrophages are functional heterogeneous, and their response to trauma and combined with endotoxin challenge are different. The results indicate that the two subgroups of macrophages play different roles in immune function disorder after trauma.

Animals↗

PubMed2003

Effects of wild-type (Trp72) and mutant (Arg72) apolipoprotein(a) kringle IV-10 on the proliferation of human arterial smooth muscle cells.

OBJECTIVE: To assess the atherogenicity of lipoprotein(a), the effect of the heterogeneity of lysine binding of apolipoprotein(a) [apo(a)], a plasminogen-like glycoprotein component on the proliferation of human arterial smooth muscle cells (SMCs). METHODS: Both wild type (wt) Trp72 and mutant (mut) Trp72-->Arg forms of apo(a) kringle IV-10 were expressed by employing a GST-gene fusion system into E. coli. The proliferation of SMCs was determined by flow cytometry and MTT colorimetry. Enzyme-linked immunosorbent assay (ELISA) assay was used to detect the active form of transforming growth factor beta(1) (TGF-beta(1)). RESULTS: Apo(a) wt-kringle IV-10 that has lysine binding properties possessed a growth-stimulating activity to SMCs on a dose-dependence manner by stimulating cells in the G(1)/G(0) phase of cell cycle to S and G(2)/M phase, and reduced significantly the amounts of endogenous active TGF-beta(1) in culture when compared with the control medium and the GST group (2.4 +/- 0.5 vs 8.6 +/- 1.6 and 9.1 +/- 1.7 ng/ml, P < 0.01). The growth-stimulating effect of apo(a) mut-kringle IV-10 deficient in lysine binding was negligible. CONCLUSIONS: Apo(a) induces SMCs growth by inhibiting the activation of latent TGF-beta(1), an activity that may involve the ability of apo(a) kringle IV-10 to bind lysine. The mitogenic effect of apo(a) wt-kringle IV-10 on SMCs might play an active role in the atherogenic function of lipoprotein(a).

Apolipoproteins↗

PubMed1975

A method for microdetermination of major neutral lipids and an application of the procedure to tissue lipids.

Cholesterol, cholesteryl esters, triglycerides and fatty acids as major neutral lipids and phospholipids were examined in quantitative analysis. The method consisted of three steps: (1) separation of lipids by one-dimensional thin-layer chromatography on silica gel plates; (2) elution of neutral lipids from scraped silica gel with chloroform-methanol (4:1); and (3) colorimetric determination of individual neutral lipids in eluates and phospholipids in silica gel. The conditions were modified for chromotropic acid reaction for determining triglycerides. Laurell's method for determining fatty acids was also modified to apply to quantitative thin-layer chromatography. The accuracy of the modified methods was well-defined as the absorbance values were on a linear curve. A quantitative study was made of the recovery of triglycerides and fatty acids after chromatography. Combining these modified methods and colorimetry for determination of cholesterol cholesteryl esters and phospholipids, the author established a micromethod for determining the major neutral lipids and phospholipids by thin-layer chromatography. Lipids from HeLa, S-3 cells were analyzed to examine the applicability of this method to tissues. The results indicated that the new method permitted a reliable estimation of the major neutral lipids and phospholipids from small amounts of tissues.

Cholesterol↗

PubMed2003

Recent advances in catalytic peroxidase histochemistry.

Immunoassays have developed to become an important analytical tool in life sciences for detection of endogenous and exogenous targets. Among the most important enzyme labels horseradish peroxidase (HRP), alkaline phosphatase (AP), and beta-D-galactosidase (GAL) is HRP the smallest enzyme and plays nowadays an outstanding role. The oldest substrates are chromogens widely applied for localization of sites of peroxidase (PO) activity in histochemistry as well as for colorimetric applications. They are represented by a diversity of aromatic amines and phenols. Encouraged by development of light excitation and measuring techniques and the commercial availability of highly sensitive equipment, luminescent labels represent the most sensitive and worthwhile detection tools to date. In contrast to chromogens fluorescent labels for detection PO activity are confined only to a few substrates developed more recently. These substrates are mostly applied in histochemistry at a short time scale due to their frequently high solubility. At the long time scale sole exception is so far the tyramine based fluorochome deposition technique (more general: catalytic reporter deposition, CARD). Despite quite different staining behavior both fluorometric and product deposition related principles are based on 4-hydroxy phenylalkyl substrates. The following article reviews basic principles of peroxidatic substrate degradation processes including chromogenic and fluorescent approaches with emphasis on recent advances in development of chromogens and fluorogens for application in histology. As a result of systematic efforts towards the design of substrates, the range of classical precipitating chromogens as well as fluorescent techniques could be complimented by novel highly sensitive substrates with superior staining capabilities: a) Metal chelating 2-hydroxy benzylamines are derived from classical aniline substrates (two steps) and utilize metal catalytic effects in an efficient intramolecular way. The enzymatically yielded dark colored polycondensation products are applicable in histochemistry, in colorimetry and especially as precipitating electron opaque labels with enhanced osmiophilic properties for light and electron microscopy. b) Fluorescent 4-hydroxy-styryl derivatives are capable of oxidative selfanchoring reactions at the cellular level close to sites of PO activity. In contrast to deposition of tyramine conjugated fluorochromes an altered fluorochrome with improved fluorescence properties is furnished during oxidative crosslinking of the substrate. This results in a highly specific and photostable fluorescence response and an outstanding low background staining. Histochemical and immunohistochemical applications are presented.

Animals↗

PubMed2000

Effect of kanglemycin C on lymphokin a production and gene expression of mouse splenocyte and macrophage.

AIM: To study the effect of kanglemycin C (KC) on production and gene transcription of lymphokins. METHODS: Cell proliferation and lymphokin activities were quantified with MTT colorimetry and ELISA, and gene transcriptions of lymphokins semi-quantified with RT-PCR. RESULTS: Suppression of KC on proliferation of enriched T-and B-cell respectively mediated by Con A and LPS was declined by addition of exogenous IL-1, IL-2, and IL-6. KC 80 nmol/L markedly inhibited IL-2 and IL-6 production and mRNA transcription of incubated mouse splenocytes induced by Con A. Additionally, KC had some suppression on IL-1beta and IL-6 productions of peritoneal macrophage stimulated by LPS (5microg/mL), whereas cyclosporine (CS) had not. CONCLUSION: Immunosuppression of KC came true partially through the decrease of IL-1beta, -2 and -6 productions, especially of IL-2. However, CS's immunosuppression was mainly through the decrease of IL-2 production.

Animals↗

PubMed2003

Growth inhibiting effects of antisense eukaryotic expression vector of proliferating cell nuclear antigen gene on human bladder cancer cells.

OBJECTIVE: To explore the growth inhibiting effects on human bladder cancer by antisense RNA targeting the proliferating cell nuclear antigen (PCNA) gene. METHODS: The eukaryotic expression vector for antisense PCNA cDNA was constructed and transferred into a bladder cancer EJ cell line. The PCNA expression in the cancer cells was detected by RT-PCR and Western blotting assays. The in vitro proliferation activities of the transferred cells were observed by growth curve, tetrazolium bromide (MTT) colorimetry, tritiated thymidine ((3)H-TdR) incorporation, flow cytometry and clone formation testing, while its in vivo anti-tumor effects were detected on nude mice allograft models. RESULTS: After the antisense vector, pLAPSN, was transferred, cellular PCNA expression was inhibited at both protein and mRNA levels. The growth rates of EJ cells were reduced from 27.91% to 62.07% (P < 0.01), with an inhibition of DNA synthesis rate by 52.31% (P < 0.01). Transferred cells were blocked at G(0)/G(1) phases in cell-cycle assay, with the clone formation ability decreased by 50.81% (P < 0.01). The in vivo carcinogenic abilities of the transferred cancer cells were decreased by 54.23% (P < 0.05). CONCLUSIONS: Antisense PCNA gene transfer could inhibit the growth of bladder cancer cells in vitro and in vivo, which provided an ideal strategy for gene therapy of human cancers.

Animals↗

PubMed2003

[Determination of serum superoxide dismutase, glutathione peroxidase, total antioxidative capacity, malondialdehyde in patients with pneumonia].

OBJECTIVE: To determine the levels of serum superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidative capacity (T-AOC) and malondialdehyde (MDA) in patients with pneumonia. METHODS: Sixty-eight patients with pneumonia were divided into group of acute pneumonia, group of chronic bronchitis complicated by lung infection, and group of bronchopneumonia. The levels of serum SOD, GSH-Px, T-AOC and MDA were detected by colorimetry in the 68 patients and 76 normal control subjects. RESULTS: The serum levels of SOD, GSH-Px and MDA were all significantly higher, while T-AOC significantly lower in the 3 patient groups than in the normal subjects. Significant difference in the measurements was also noted between the 3 groups (P < 0.01). CONCLUSION: The determination of serum SOD, GSH-Px, T-AOC and MDA may be helpful for the diagnosis and treatment of pneumonia.

Adult↗

PubMed1975

Effect of sodium dodecyl sulfate on immuno-electrosyneresis between normal human erythrocyte membrane and sera of systemic lupus erythematosus patients.

An anti-membrane antibody was present in the sera of systemic lupus erythematosus patients in immunoelectrosyneresis with sodium dodecyl sulfate (SDS) solubilized erythrocyte membrane as antigen. The SDS bound to protein was detected by chromatography at 10(-3)M concentration under U.V. light, at 10(-5)M concentration by the distilled water spray method and at 10(-6)M concentration by using rosaniline hydrochloride colorimetry. SDS was removed from the membrane protein at a concentration of 10(-3)M by the first gel filtration of Sephadex G-25 column and at a concentration of 10(-6)M by rechromatography of the same column. More than 99% of SDS in the solubilized erythrocyte membrane was removed by gel filtration. The antigenicity was still positive in the refiltrated fractions of systemic lupus erythematosus patients. Therefore, all precipitates in the gels were antigen-antibody aggregates.

Antibodies↗

PubMed1992

Classification and measurement of nutritionally important starch fractions.

For nutritional purposes, starch in foods may be classified into rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS). RS may be further divided into three categories according to the reason for resistance to digestion. A method is reported for the measurement of total starch, RDS, SDS, RS and three RS fractions in starchy foods, using controlled enzymic hydrolysis with pancreatin and amyloglucosidase. The released glucose is measured by colorimetry, using a glucose oxidase kit. Values for RDS and SDS in foods obtained by the method reflect the rate of starch digestion in vivo. Values for RS are similar to the amounts of starch escaping digestion in the small intestine of ileostomates, and are a guide to the amounts of starch likely to enter the colon for fermentation. Results are given for a number of starchy foods.

Dietary Fiber↗

PubMed1992

[Electron microscopic observation on the effect of electroacupuncture (EA) on the ultrastructure of nucleus raphe dorsalis (NRD) in rats].

Nucleus raphe dorsalis (NRD) plays an important role in acupuncture analgesia. The aim of this investigation is to determine the effects of electroacupuncture (EA) analgesia on the ultrastructure of NRD. 12 Wistar rats (220-250g) were divided into control and experiment groups. Pain threshold was determined by potassium iontophoretic colorimetry. EA was applied at bilateral "Zusanli" points. The effective analgesia animals and control animals were sacrificed and the NRD were taken out for electron microscopic observation. In EA analgesia groups, NRD was observed the number of the clear round vesicle-containing terminals and clear round vesicles with the granular vesicle-containing terminals showed a significant decrease and sometimes vesicles were emptied. The area of presynaptic terminals were expanded. Some synaptic gaps appeared narrow profiles. Part of the mitochondria and endoplasmic reticulum in neuron and neurogliocytes appeared the expanded profiles. These ultrastructural change of the NRD in EA analgesia might indicate the neurons and neurogliocytes were in active functional state.

Acupuncture Analgesia↗

PubMed1992

Analysis of glycated albumin in postmortem blood samples as the diagnostic parameters of diabetes mellitus.

Glycated hemoglobin (GHb), fructosamine and glycated albumin (GA) in hemolytic sera from cadavers were analyzed for the postmortem diagnosis of diabetes mellitus. The levels of GHb and fructosamine were determined by boronate affinity chromatography and colorimetry, respectively. Albumin fraction was isolated from the samples by Affi-Gel Blue affinity chromatography. The glycated and non-glycated molecules were separated by boronate affinity chromatography, and quantitated by bromcresol green method. Fructosamine could not be analyzed from highly hemolytic sera containing more than 10 g/l hemoglobin. In such samples, the levels of GHb and GA were deviated from the standard values, indicating their postmortem degradation. In less hemolytic samples, GA was as informative as GHb and fructosamine for the diagnosis of diabetes mellitus.

Blood Specimen Collection↗

PubMed2003

Effects of blocking androgen receptor expression with specific hammerhead ribozyme on in vitro growth of prostate cancer cell line.

OBJECTIVE: To study the possibility of gene therapy for prostate cancer by blocking androgen receptor (AR) gene expression using a specific hammerhead ribozyme (RZ). METHODS: The hammerhead ribozyme expression vector pcDNA-hAR-RZ, specific to AR mRNA, was constructed and transfected into the prostate cancer cell line LNCaP by using lipofectamine. Androgen receptor expression was measured by RT-PCR and immunohistochemical methods. Cellular proliferation activities were assayed using the tetrazolium bromide colorimetry method; cell cycle changes were observed by flow cytometry; and cell apoptosis was detected by the TdT-mediated dUTP-biotin nick end labeling method. RESULTS: One to seven days after transfection with the ribozyme expression vector, AR mRNA expression at molecular and protein levels in LNCaP cells decreased by 32.6% - 40.7% (P < 0.05) and 21.0% - 87.64% (P < 0.05) respectively, and cell proliferation was inhibited by 18.28% - 35.34% (P < 0.05). Meanwhile, the cell cycle was arrested at the G2/M stage, and apoptotic morphological changes occurred with an apoptosis rate of 25.17% (P < 0.01). CONCLUSION: Ribozyme specific against AR mRNA is capable of inhibiting the expression AR and inducing the apoptosis in prostate cancer cells.

Apoptosis↗

PubMed2003

Relationship between cardiotonic effects and inhibition on cardiac sarcolemmal Na+,K+-ATPase of strophan-thidin at low concentrations.

AIM: To evaluate the effects of strophanthidin (Str) on cardiac contractile function and sarcolemmal Na+, K+-ATPase activities in isolated guinea-pig hearts. METHODS: Isolated guinea-pig hearts were perfused through aorta in a Langendorff mode. Heart rate (HR), left ventricular pressure (LVP), and first derivatives (+/-dp/dt(max)) of LVP were recorded by eight-channel physiological instrument. Cardiac sarcolemmal Na+, K+-ATPase activities were determined with colorimetry. RESULTS: Str 0.1 nmol/L stimulated the Na+, K+-ATPase activities (P<0.05), but had no effect on HR, LVP, and +/-dp/dt(max). Str 1 nmol/L increased +dp/dt(max) (P<0.05) and Na+, K+-ATPase activities (P<0.01). Str 10 and 100 nmol/L significantly increased both LVP (P<0.05) and +dp/dt(max) (P<0.05 or P<0.01), and had no significant effects on Na+, K+-ATPase activities. However, Str 1-100 micromol/L at first enhanced the LVP and +dp/dtmax (P<0.01), then reduced them resulting from irregular contraction, and effects of Str on Na+, K+-ATPase activities revealed a concentration-dependent inhibition (P<0.01). CONCLUSION: The positive inotropic effects and irregular contraction produced by Str at higher concentrations result from the inhibition of Na+, K+-ATPase activities, and the positive inotropic effects of Str at lower concentrations are not related to the inhibition of the Na+, K+-ATPase activities.

Animals↗

PubMed2003

[Protective effect and mechanism of pretreatment with curcumin on infectious brain edema in rats].

UNLABELLED: Curcumin is a natural compound extracted from the spice tumeric, possessing both anti-inflammatory antioxidant, and anti-carcinogenic effect, is a potent stimulator of the stress-induced expression of heat shock protein 70 kd (HSP70). OBJECTIVES: To study the protective effect of pretreatment with curcumin against infectious brain edema in rats, and investigate its mechanism by assessing the free radical, cytokine and HSP70 expression of the brain. METHODS: An animal model of infectious brain edema induced by injecting pertussis bacilli (PB) through carotid artery was used. SD rats were randomly divided into five groups: (1) Normal control group (NS group, n = 9); (2) Infectious brain edema group (PB group, n = 12); (3) DMSO control group (DMSO group, n = 9); (4) HS pretreatment group (HS group, n = 9); (5) Curcumin pretreatment group (CUR group, n = 13). The water content (WC), Na(+) and K(+) content in brain tissue were measured. The content of malondialdehyde (MDA) and super oxide dismitase (SOD) were assessed by chemical colorimetry. The levels of tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta) were detected by ELISA. The HSP70 expression was examined by Western blot analysis. RESULTS: (1) The WC and Na(+), MDA, TNF-alpha and IL-1beta were increased in PB group compared with NS group (P < 0.01); they were decreased in HS and CUR groups compared with PB group (P < 0.01 or P < 0.05). (2) The content of SOD was decreased in PB group than in NS group (P < 0.05), and was increased in HS and CUR group Compared with PB group, (P < 0.05). (3) Western blot analysis showed that the band density areas of HS, CUR and PB groups were higher than those in NS and DMSO groups, especially in CUR group (P < 0.01). CONCLUSION: Pretreatment with curcumin showed a protective effect against infectious brain edema in rats. The effect might be associated with antioxidant, inhibition of the activity of cytokines and inducing expression of HSP70 by curcumin.

Animals↗

PubMed1992

Statistical analysis of relationship between net protein utilization in rat and amino acid composition in cooked foods.

To determine the relation between protein nutritive value and amino acid composition of protein in cooked food, statistical analysis was carried out on thirty cooked foods selected from Japanese daily meal. The food samples were cooked, and powdered after freeze-drying. The amino acid composition was determined by liquid chromatography and colorimetry. The Wistar rats were put on the 7% cooked food protein diet and NPU (net protein utilization) was determined. Linear multiple regression analysis was made between NPU and the ratio of individual essential amino acid in the cooked food protein (mg/Ng)/the corresponding amino acid in the reference protein (mg/Ng). The regression equation for the predicted net protein utilization (NPUp) reads as follows: [formula: see text] Highest correlation coefficient (r = 0.93, p < 0.01) was obtained between NPU and NPUp of the protein in the cooked food.

Algorithms↗

PubMed2003

[Effects of low frequency pulsed magnetic field on the proliferation and differentiation of HepG2 cells].

OBJECTIVE: To study the effects of low frequency pulsed magnetic field on the proliferation and differentiation of HepG2 cells. METHODS: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) colorimetry method and ELISA assay of alpha-fetoprotein (AFP) were used to determine the cell proliferation and differentiation after the cells were exposed to pulsed magnetic fields with different frequency but the same field intensity. RESULTS: There were no significant differences in cell proliferation between sham and treated groups exposed to the field of 80 Hz, 1.55 mT for 1, 4, 8, 12, 24 h (P > 0.05). There were also no significant differences in cell proliferation and AFP secretion between sham and treated groups exposed to 16 Hz, 1.55 mT pulsed magnetic fields for 1, 4, 8, 24 h (P > 0.05). CONCLUSION: There were no "window effects" found in HepG2 cells proliferation or AFP secretion at 16 Hz and 80 Hz pulsed magnetic fields.

Cell Differentiation↗

PubMedDate not supplied

[Effect of beta-carotene accumulation on spectral parameters of microscopic fungi Blakeslea trispora biomass].

Parameters of reflectance spectra in visible region and colorimetry for Blakeslea trispora biomass with different content of beta-carotene were determined. Correlation level of pigment accumulation and spectral characteristics were revealed. It is established, that objective control of color characteristics for biomass is possible using measurement of colorimetric parameters.

Biomass↗