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1.
Appl Clin Inform ; 8(3): 924-935, 2017.
Article in English | MEDLINE | ID: mdl-30027541

ABSTRACT

Electronic Health Records (EHRs) have been quickly implemented for meaningful use incentives; however these implementations have been associated with provider dissatisfaction and burnout. There are no previously reported instances of a comprehensive EHR educational program designed to engage providers and assist in improving efficiency and understanding of the EHR. Utilizing adult learning theory as a framework, Stanford Children's Health designed a tailored provider efficiency program with various inputs from: (1) provider specific EHR data; (2) provider survey data; and (3) structured observation sessions. This case report outlines the design of this individualized training program including team structure, resource requirements, and early provider response. CITATION: Stevens LA, DiAngi YT, Schremp JD, Martorana MJ, Miller RE, Lee TC, Pageler NM. Designing An Individualized EHR Learning Plan. Appl Clin Inform 2017; 8:924-935 https://doi.org/10.4338/040054.

2.
Cell Mol Biol (Noisy-le-grand) ; 45(4): 445-52, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10432191

ABSTRACT

Rheumatoid arthritic (RA) and osteoarthritic (OA) synovial cells in culture differ in their metabolic and proliferative behaviour. To assess links between these properties and nuclear changes, we used image analysis to study chromatin texture, together with nuclear morphometry and densitometry of OA and RA cells in primary culture. Chromatin pattern at the third day (D3) was heterogeneous and granular with chromatin clumps whereas at the final stage (D11) of culture a homogeneous and finely granular chromatin texture was observed. This evolution indicates global chromatin decondensation. These characteristics were more marked for RA than for OA nuclei. At each culture time, RA nuclei could be discriminated with high confidence from OA ones from parameters evaluating the organization of the chromatine texture. Nuclear image analysis is thus a useful tool for investigating synovial cell biology.


Subject(s)
Arthritis, Rheumatoid/pathology , Image Processing, Computer-Assisted , Osteoarthritis/pathology , Cell Nucleus/pathology , Cells, Cultured , Chromatin , Humans , Synovial Membrane/cytology
3.
Anal Cell Pathol ; 11(1): 1-12, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8844101

ABSTRACT

Human synovial cells in primoculture are an interesting model for the study of articular joint diseases and anti-rheumatic drugs. Based on results obtained by image cytometry of Feulgen-stained nuclei, we describe the heterogeneity of synovial cell populations and their progression during culture time in primoculture. Using the hydrolysis properties of the Feulgen reaction and their variations dependent on fixatives, we demonstrate the high acid-lability of the condensed chromatin observed in short term cultured nuclei compared to the acid-resistance of decondensed chromatin in long term cultured nuclei; these variations being probably induced by modifications in the molecular supra-organisation of chromatin during the aging of a culture. Finally, due to the cellular heterogeneity of the biological model and its evolution during culture progression, technical compromises are proposed to obtain optimal Feulgen staining, using Böhm-Sprenger fixative and a 1 h hydrolysis by 6 M HCl at 20 degrees C.


Subject(s)
Coloring Agents , Osteoarthritis/pathology , Rosaniline Dyes , Staining and Labeling/methods , Synovial Membrane/pathology , Tissue Fixation/methods , Aged , Aged, 80 and over , Cells, Cultured , Chromatin/genetics , Chromatin/metabolism , DNA Replication , Female , Flow Cytometry , Humans , Hydrolysis , Kinetics , Male , Middle Aged , Ploidies
4.
J Clin Endocrinol Metab ; 75(3): 865-70, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1517379

ABSTRACT

The antiproliferative effect of RU486 and its effect combined with tamoxifen on the growth and cell cycle kinetics parameters on the MCF-7 human carcinoma cells were investigated. When MCF-7 cells in the exponential growth phase were treated with RU486 (10(2) nmol/L), a time-dependent cell growth inhibition was observed which was significant 5 days after the beginning of treatment. This inhibition was accompanied by a time- and dose-dependent decrease in the percentage of S and G2-M phase cells and a concomitant increase in the percentage of cells in the G0/G1 phase of the cell cycle. With tamoxifen (10(5) pmol/L), growth inhibition was obtained after 4 days of treatment of cells, and the blockage of the cell cycle occurred in the G0/G1 phase. In the case of simultaneous treatment of MCF-7 cultures with RU486 (10(2) nmol/L) and tamoxifen (10(5) pmol/L), we observed a synergistic inhibitory effect on the proliferative rate for short treatment (less than or equal to 3 days), whereas RU486 or tamoxifen alone had no effect. For the intermediate treatment (4 days), the combined effect of RU486 and tamoxifen was not significant compared to the effect of tamoxifen alone. For the long treatment (greater than 4 days), there were no differences between the number of cells in the treated cultures under different experimental conditions, but all were inhibited compared to those in control cell cultures. This simultaneous treatment of cells does not induce any change in the distribution of cells in the different cell cycle phases compared to tamoxifen percentages. These results suggest that RU486 is a cell cycle phase-specific growth inhibitory agent, and a combination of antiestrogen/antiprogestin should be considered as a possible improvement in breast cancer endocrine therapy.


PIP: The antiproliferative effect of the antiprogestational agent RU-486 (100 nmol/L), alone and its additive effect in combination with the antiestrogenic tamoxifen (100,000 pmol/L) on the growth and cell cycle phases of the human breast cancer cell line MCF7, which is ER and PR positive, using image cytometry was investigated. On days 2, 3, 4, 5, 7, and 9, cells were harvested from control and RU-486-, tamoxifen, and RU-486- and tamoxifen-treated cultures and counted with an hemocytometer. Cell number increased in the RU-486-treated culture for the first 4 days as well as in the control culture. RU-486 treatment of cells for 5 days produced a significant time-dependent cell growth inhibition (P 0.01) compared with that in the control cells. With tamoxifen (100,000 pmol/L), growth inhibition was obtained after 4 days of treatment of cells, and the blockage of the cell cycle occurred in the G0.G1 phase. For the short treatment a significant synergistic growth inhibition (P 0.05 and P 0.01 on days 2 and 3, respectively) compared to RU-486 or tamoxifen alone, which had no effect compared to control cells. In the case of simultaneous treatment of MCF7 cultures with RU-486 (100 nmol/L) and tamoxifen (10000 pmol/L), a synergistic inhibitory effect of the proliferative rate was not produce an effect. During intermediate treatment (4 days), the combined effect of RU-486 and tamoxifen was not significant compared to the effect of tamoxifen alone. On the other hand, tamoxifen inhibited growth compared to that in control cells (P 0.05). These findings suggest that RU-486 is a cell cycle phase-specific growth inhibitory agent, and a combination of antiestrogen and antiprogestin agents may be of possible use in breast cancer endocrine therapy.


Subject(s)
Breast Neoplasms/pathology , Carcinoma/pathology , Mifepristone/pharmacology , Tamoxifen/pharmacology , Breast Neoplasms/genetics , Carcinoma/genetics , Cell Count/drug effects , Cell Cycle/drug effects , Cell Division/drug effects , DNA, Neoplasm/analysis , Drug Combinations , Humans , Osmolar Concentration , Tumor Cells, Cultured
5.
Anticancer Res ; 11(4): 1469-75, 1991.
Article in English | MEDLINE | ID: mdl-1746904

ABSTRACT

Since gossypol, a naturally occurring component of cottonseed oil, exhibits a broad spectrum of activities, we have examined it as an antitumor agent on breast cancer. The effects of different concentrations of gossypol on the T-47D human breast cancer cell cycle phases were studied using cytometric image processing on Feulgen stained nuclei. The proportion of cells at different cell cycle phases was determined by discriminate analysis of the image parameters and gave good classification ranging from 86 to 100%. Gossypol was found to increase the G0/G1 fraction of the T-47D cells. This cell kinetic alteration by gossypol was shown to be dose dependent and reversible. Complete reversal of the effect of gossypol was observed after four days with a simple change to gossypol-free medium. The cells then progressed into S and G2/M phase, thus indicating that gossypol-treated cells remain viable. Gossypol was shown to have a strong inhibitory effect on cellular proliferation in T-47D cells. It was also found that this agent is only toxic to cells at the highest dose tested (10 microM). The results of this study may be of clinical significance in the treatment of breast cancer, since gossypol shows strong antiproliferative properties.


Subject(s)
Cell Cycle/drug effects , Gossypol/pharmacology , Adenocarcinoma , Breast Neoplasms , Cell Line , Cell Nucleus/drug effects , Cell Nucleus/ultrastructure , Cell Survival/drug effects , DNA, Neoplasm/analysis , Dose-Response Relationship, Drug , Female , Humans , Kinetics
6.
Ann Chir Main Memb Super ; 10(4): 337-41, 1991.
Article in French | MEDLINE | ID: mdl-1720970

ABSTRACT

We observed a case of compression of the deep branch of the ulnar nerve distal to the piso-hamate hiatus due to an aberrant fibrous band arising from the hamulus ossi hamatum and ending in the flexor digiti minimi muscle. An anatomical study of eleven fresh cadaver hands revealed that between the piso-hamate hiatus and the palm, the nerve passes through an osteo-fibrous tunnel in which multiple anomalies can occur. The authors think that ulnar nerve neurolysis at the wrist must always extend up to the palm.


Subject(s)
Carpal Bones , Congenital Abnormalities/pathology , Nerve Compression Syndromes/etiology , Tendons/abnormalities , Ulnar Nerve , Adult , Cadaver , Congenital Abnormalities/epidemiology , Congenital Abnormalities/surgery , Humans , Male , Nerve Compression Syndromes/surgery
7.
Cancer Res ; 50(4): 1195-200, 1990 Feb 15.
Article in English | MEDLINE | ID: mdl-2297768

ABSTRACT

Hormonal modulation of glucose-6-phosphate dehydrogenase (G6PD) and of utilization pathways of NADPH generated by G6PD was studied in the MCF-7 human breast cancer cell line, using a quantitative cytochemical method. Our results show that G6PD is increased by 17 beta-estradiol (estradiol) and synthetic progestin (promegestone R5020). The synthetic antiestrogen tamoxifen has no effect on G6PD activity. When it is present in the medium with estradiol, tamoxifen can oppose the stimulatory effect of estradiol on G6PD activity. Mifepristone (RU 38486) has no effect on G6PD activity, but it inhibits the R5020 stimulation of G6PD activity. After MCF-7 pretreatment with estradiol, there is a much stronger stimulation of G6PD activity by R5020. When we studied the effect of the steroid on the two utilization pathways of NADPH generated by G6PD activity, we observed that, in the cells treated with estradiol, there is an increase in reducing equivalents generated by G6PD activity which only affects the NADPH2 pathway, and that there is cell growth stimulation. When tamoxifen is present in the medium, we found no effect on the NADPH utilization pathways, nor on cell growth. In the presence of R5020, the NADPH2 pathway activity is increased but, under our experimental conditions, there was no effect on cell growth. On the other hand, even though RU 38486 is without effect on total G6PD activity, it does cause a modification in the distribution of reducing equivalents: the NADPH2 pathway activity is decreased, while the NADPH1 pathway is stimulated.


Subject(s)
Breast Neoplasms/enzymology , Estradiol/pharmacology , Glucosephosphate Dehydrogenase/metabolism , NADP/biosynthesis , Norpregnadienes/pharmacology , Promegestone/pharmacology , Breast Neoplasms/pathology , Cell Division/drug effects , Drug Interactions , Humans , Mifepristone/pharmacology , Premedication , Tamoxifen/pharmacology , Tumor Cells, Cultured/metabolism
8.
Am J Physiol ; 257(5 Pt 1): G760-5, 1989 Nov.
Article in English | MEDLINE | ID: mdl-2596609

ABSTRACT

A microdensitometric method was employed to determine enzyme activities in situ in undisrupted tissue rat duodenum. The effect of 1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3] on glucose-6-phosphate dehydrogenase (G6PD) activity and on the two utilization pathways of synthesized NADPH, H1 (mixed function oxidation) and H2 (biosynthesis), was studied. In normal animals, a crypt-to-villus gradient of G6PD activity and of both NADPH utilization pathways was observed. A high level of NADPH utilization occurred predominantly via the H2 pathway. In vitamin D-deficient rat animals, G6PD activity in the middle part of the villus was approximately 60% lower than in normal animals [10.05 +/- 0.35 vs. 3.95 +/- 0.26 (means +/- SE) A585.min-1.micron-3 X 10(5), P less than 0.001] with reduced NADPH utilization via the H2 pathway (8.39 +/- 0.49 vs. 2.73 +/- 0.43 A585.min-1.micron-3 X 10(5), P less than 0.001) but not the H1 pathway (1.65 +/- 0.17 vs. 1.22 +/- 0.19 A585.min-1.micron-3 X 10(5), P = NS). Intraperitoneal administration of 1,25(OH)2D3 (500 pmol) to vitamin D-deficient animals resulted in increased G6PD activity within 30 min (4.09 +/- 0.38 vs. 5.51 +/- 0.39 A585.min-1.micron-3 X 10(5), P less than 0.05), attaining normal levels within 2 h. The H2 but not the H1 pathway of NADPH utilization increased significantly in response to 1,25(OH)2D3. This increase is essentially located in the basal and middle parts of the villus. Thus 1,25(OH)2D3 may influence biosynthesis in the duodenum via stimulation of G6PD activity and the H2 pathway of NADPH utilization.


Subject(s)
Calcitriol/pharmacology , Duodenum/enzymology , Glucosephosphate Dehydrogenase/metabolism , Animals , Densitometry , Duodenum/cytology , Epithelial Cells , Epithelium/enzymology , Kinetics , Male , Microvilli/enzymology , NADP/metabolism , Rats , Rats, Inbred Strains , Reference Values
9.
J Steroid Biochem ; 32(2): 271-7, 1989 Feb.
Article in English | MEDLINE | ID: mdl-2921868

ABSTRACT

The effects of 17 beta-estradiol (estradiol), synthetic progestin R5020 and their antagonists, tamoxifen (Tam) and synthetic RU38486 on lactate dehydrogenase (LDH) activity in MCF-7 human breast cancer cells during the growth period were studied. A specially developed quantitative cytochemical assay was used; LDH activity is expressed per cell, and is thus independent of the positive and negative growth effects of the hormones and antagonists. Estradiol and R5020 stimulated LDH activity after similar exposures (6-48 h) and the stimuli were concentration dependent over the range 10(-7) M to 10(-10) M. As for the antagonists, RU38486 stimulated LDH activity in much the same way as estradiol and R5020; Tam alone, on the other hand, does not stimulate LDH, but when added to estradiol, Tam inhibits estradiol mediated LDH activation. When present at half-stimulant concentration, estradiol + R5020 and estradiol + RU38486 exhibit additive effects on LDH activity. Thus LDH appears to be an interesting tool for the study of hormone and antagonist effects in MCF-7 breast cancer cells.


Subject(s)
Breast Neoplasms/enzymology , Estradiol/pharmacology , Estrenes/pharmacology , L-Lactate Dehydrogenase/metabolism , Norpregnadienes/pharmacology , Promegestone/pharmacology , Tamoxifen/pharmacology , Cell Line , Dexamethasone/pharmacology , Dihydrotestosterone/pharmacology , Female , Histocytochemistry , Humans , Mifepristone
10.
Cell Biochem Funct ; 7(1): 1-6, 1989 Jan.
Article in English | MEDLINE | ID: mdl-2752532

ABSTRACT

Human breast cancer cell lines have been shown to possess high affinity receptors for 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) and their growth is inhibited by this steroid. The present study examines the effect of 1,25(OH)2D3 on the activity of glucose-6-phosphate dehydrogenase (G6PD) in cells of a human breast cancer cell line MCF-7. G6PD, an enzyme which controls the hexose monophosphate shunt, is elevated and sensitive to 17 beta-estradiol in breast tumors. G6PD activity was stimulated by 1,25(OH)2D3 in a dose-dependent manner at very low concentrations of steroid (10(-10)-10(-12) M). 1,25(OH)2D3 increased maximum velocity without modifying the affinity constant of the enzyme for glucose-6-phosphate.


Subject(s)
Breast Neoplasms/enzymology , Calcitriol/pharmacology , Glucosephosphate Dehydrogenase/metabolism , Enzyme Activation/drug effects , Estradiol/pharmacology , Female , Humans , Kinetics , Stimulation, Chemical , Tumor Cells, Cultured
11.
J Urol (Paris) ; 95(1): 3-9, 1989.
Article in French | MEDLINE | ID: mdl-2732483

ABSTRACT

Image processors and present specific software applications have now placed scanning microcytometry in the ranks of other conventional technics for routine laboratory examinations, particularly for urinary cytology and DNA measurements (ploidy). Conventional urinary sediment smears of 52 patients with bladder tumor were digitized, processed and statistically analyzed by the image analyzer, Samba. They were automatically classified and ploidy measurements were made and compared with 6 conventional cytological diagnostics for each smear. The Samba program assigns the cell images to two classes, negative and positive. 100% of the cells were correctly classed with respect to the cytologist's diagnostics. Within the positive class the degree of malignancy established by the program was the same as the cytologist's classifications. For smears of class III, the comparison of the diagnostics of the cytologists for each patient permitted the validation of the differential classification, negative-positive, made using quantitative cytology. The interpretation of the two DNA histogram parameters, the degree of ploidy and the proliferation index, provided an excellent prognosis of which patients would show tumoral recrudescence, as verified by follow ups.


Subject(s)
Cytophotometry/methods , Ploidies , Urinary Bladder Neoplasms/pathology , DNA, Neoplasm/analysis , Diagnosis, Differential , Humans , Image Processing, Computer-Assisted , Prognosis , Urinary Bladder Neoplasms/classification , Urinary Bladder Neoplasms/urine
12.
Endocrinology ; 123(4): 1778-82, 1988 Oct.
Article in English | MEDLINE | ID: mdl-3416814

ABSTRACT

Recent reports have suggested that the action of calcitriol is much more rapid than previously thought. It is thus possible that some actions do not depend on de novo protein synthesis. A precise microdensitometric technique has been used to characterize the time course of the intestinal brush border alkaline phosphatase (AP) response of rat duodenal villi to the administration of calcitriol as AP activity has been shown to be dependent on the vitamin D status of the animal. The technique enables AP activity to be determined in situ without tissue disruption. After ip administration of 200 ng calcitriol to vitamin D-deficient male Wistar AF rats, a biphasic AP response was observed with an early peak within 1 h (0.068 +/- 0.011 vs. 0.101 +/- 0.003 integrated extinction (IE) min.micron 3 X 10(3), P less than 0.05) and a second at between 6 and 8 h (0.088 +/- 0.005 vs. 0.172 +/- 0.003 IE/min.micron 3 X 10(3), P less than 0.001). In a further experiment, the early response to calcitriol was reexamined with observations at 0, 10, 30, 45, and 60 min after administration of either calcitriol or vehicle (n = 5 pairs per time point). AP activity was significantly increased in the calcitriol group compared with the vehicle-treated group as early as 10 min after administration (0.132 +/- 0.003 vs. 0.151 +/- 0.005 IE/min.micron 3 X 10(3), P less than 0.02) and reached a peak 45 min after administration at which time AP activity was equal to that found in normal vitamin D-replete animals (0.193 +/- 0.003 vs. 0.192 +/- 0.002 IE/min.micron (3) X 10(3), P greater than 0.5). The speed of this response indicates it to be unlikely to depend on de novo protein synthesis.


Subject(s)
Alkaline Phosphatase/metabolism , Calcitriol/pharmacology , Duodenum/enzymology , Animals , Kinetics , Male , Rats , Rats, Inbred Strains , Reference Values , Time Factors
14.
Cancer Res ; 47(19): 5116-9, 1987 Oct 01.
Article in English | MEDLINE | ID: mdl-3621197

ABSTRACT

Although increasing levels of glucose-6-phosphate dehydrogenase (G6PD) have been widely reported in human breast tumor tissue, the effects of 17 beta-estradiol and progesterone on this key enzyme of cellular growth processes have not been well documented. Cellular heterogeneity of breast tumor tissue, coupled with the low sensitivity of classical biochemical assays of G6PD, are the main sources of difficulties in these studies. In the present report, the effects of estradiol and a progesterone analogue (R5020) on G6PD activity were studied using the MCF-7 cell line and a cytochemical assay of G6PD activity. Our results show that: (a) this assay can be used to perform quantitative measurements of G6PD on individual cells using small number of cells (20-30); and (b) both estradiol (10(-8)-10(-5) M) and R5020 (10(-9)-10(-5) M) stimulate the G6PD activity in dividing MCF-7 cells. Maximal stimulation (20-30%) was obtained after 24 h of treatment. This combination of MCF-7 cells and cytochemical assay is suitable for further studies on the effects of estradiol and R5020 stimulation of G6PD activity in breast tumors.


Subject(s)
Breast Neoplasms/enzymology , Estradiol/pharmacology , Glucosephosphate Dehydrogenase/analysis , Norpregnadienes/pharmacology , Promegestone/pharmacology , Cell Division , Cells, Cultured , Female , Histocytochemistry , Humans , Kinetics , NAD/analysis
15.
Horm Metab Res ; 18(9): 642-6, 1986 Sep.
Article in English | MEDLINE | ID: mdl-2430877

ABSTRACT

Parathyroid hormone (PTH) has been shown to modify Ca2+ and Na+ transport in several epithelia. The molecular mechanisms of these effects are poorly understood. We investigated here whether PTH may modify Na+ and K+ transport across the human red blood cell membrane in vitro and ex vivo. Fourteen patients with severe primary or secondary hyperparathyroidism and hypercalcemia were studied before and 5-7 days after surgical parathyroidectomy. Erythrocyte ouabain-sensitive as well as furosemide-sensitive Na+ efflux rates of the patients were comparable to that of healthy volunteers and remained unchanged after parathyroidectomy. Moreover, erythrocyte Na+ fluxes of control subjects remained unchanged when red blood cells were incubated in the presence of 1.0 IU/ml of bovine PTH (1-85). However, erythrocytes from hyperparathyroid patients showed a significant increase in passive K+ permeability when compared to that of healthy controls (p less than 0.05). This abnormality could be corrected in vivo after parathyroidectomy and in vitro using quinine, respectively. It is concluded that hyperparathyroidism induces a moderate increase in Ca2+ dependent K+ permeability of erythrocytes ("Gardos effect") which is reversible after parathyroidectomy.


Subject(s)
Erythrocytes/metabolism , Hyperparathyroidism/blood , Potassium/blood , Adult , Aged , Cell Membrane Permeability/drug effects , Female , Humans , Hyperparathyroidism/surgery , Ion Channels/metabolism , Male , Middle Aged , Parathyroid Glands/surgery , Parathyroid Hormone/pharmacology , Quinine/pharmacology , Sodium/blood
16.
Surg Radiol Anat ; 8(3): 189-95, 1986.
Article in English | MEDLINE | ID: mdl-3099410

ABSTRACT

A biometric study based on 20 human scapulae made it possible to specify the variations in the gap of the coraco-acromial arch in relation to its depth and height. A graphic representation in rectangular coordinates, then in spatial representation in relation to the three planes of reference, leads to the following findings: the bony variations in the arch occur essentially: at the coracoid apophysis, and two types of arch can be distinguished depending on the predominance of bony or of ligamentous components.


Subject(s)
Acromion/anatomy & histology , Scapula/anatomy & histology , Biometry/methods , Humans , Medical Illustration
17.
Eur J Biochem ; 148(3): 587-91, 1985 May 02.
Article in English | MEDLINE | ID: mdl-3996396

ABSTRACT

Kinetic analysis of lactate dehydrogenase activity in intact cultured chondrocytes was performed in situ by coupling cell culture and microcytophotometry. Cells were cultured on glass microscope slides divided into eight chambers and studied during the growth cycle in monolayer areas. Lactate dehydrogenase activity was assayed by the reduction of neotetrazolium in the presence of phenazine methosulfate. Quantification of formazan deposits within the cells was performed by scanning and integrating microdensitometry at the isosbestic wavelength of 585 nm. Results indicate the following (a) A kinetic characterization was possible: apparent constants, Km and Ks of this two-substrate enzyme were graphically determined Ks = 1.05 +/- 0.08 and 0.56 +/- 0.05 mM for lactate and NAD respectively and Km = 0.64 +/- 0.03 and 0.37 +/- 0.02 mM for lactate and NAD respectively. (b) Inhibition by lactate concentrations above 10 mM and pyruvate concentration of 1 mM, is in agreement with the well known high anaerobic glycolytic metabolism of chondrocytes. This was confirmed by electrophoresis on cellulose acetate which demonstrated a M3-H isoenzyme form in cultured chick chondrocytes. This study shows that microcytophotometric analysis of lactate dehydrogenase in cultured chondrocytes may be an interesting alternative to mass culture cells followed by classical biochemical studies.


Subject(s)
Cartilage/enzymology , L-Lactate Dehydrogenase/metabolism , Animals , Cells, Cultured , Chickens , Electrophoresis/methods , Histocytochemistry , Isoenzymes/isolation & purification , Kinetics , Substrate Specificity
19.
J Biol Chem ; 259(19): 11658-61, 1984 Oct 10.
Article in English | MEDLINE | ID: mdl-6480576

ABSTRACT

A quantitative microdensitometric study has been designed to characterize in situ intestinal brush border-bound alkaline phosphatase of rat duodenal villosities. Intestinal slices were incubated with beta-glycerophosphate as substrate. Free phosphate liberated was precipitated in presence of a lead reagent as lead sulfide. The precipitate was quantified in situ by scanning and integrating microdensitometry. Kinetic parameters of the reaction were determined at 37 degrees C, pH 8.8, in the middle part of the villosities. Apparent Michaelis constant (Km) for beta-glycerophosphate was found to be 8.16 +/- 0.56 mM (mean +/- S.E.). Maximal enzyme activation was obtained at pH 8.5. Maximal inhibition of enzyme activity was observed in the presence of L-phenylalanine (30 mM) or theophylline (5 mM). Along the villosity axis, enzyme activity rose from the crypt up to the midportion of the villosity and finally decreased at the tip region. In phosphate-depleted rats, enzyme activity was increased in all portions of the villosity, with conservation of the same activity gradient. In this situation, kinetic analysis showed a marked decrease of Km, i.e. 4.56 +/- 0.39 mM (mean +/- S.E.) as compared to normal rats.


Subject(s)
Alkaline Phosphatase/analysis , Intestines/enzymology , Phosphates/metabolism , Animals , Densitometry , Hydrogen-Ion Concentration , Male , Microvilli/enzymology , Phenylalanine/pharmacology , Rats , Rats, Inbred Strains , Theophylline/pharmacology , Time Factors
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