IN VITRO EFFECTS OF LATS AND TSH ON PHOSPHODIESTERASE ACTIVITY IN HUMAN THYROID HOMOGENATES

1971 ◽  
Vol 67 (2) ◽  
pp. 209-215 ◽  
Author(s):  
K. Miyai ◽  
N. Amino ◽  
M. Azukizawa ◽  
Y. Kumahara
Keyword(s):  
Enzyme Activity ◽  
Adenosine Monophosphate ◽  
Human Thyroid ◽  
Phosphodiesterase Activity ◽  
Significant Difference ◽  
In Vitro Effects ◽  
Long Acting ◽  
Bovine Tsh

ABSTRACT The in vitro effects of long-acting thyroid stimulator (LATS) and thyrotrophin (TSH) on phosphodiesterase activity in human thyroid homogenates were studied. The enzyme activity was estimated by the destruction of 3H-cyclic 3′,5′-adenosine monophosphate. Bovine TSH had no effect on the enzyme activity. Five experiments were carried out using different batches of LATS-IgG and normal IgG which were preincubated with thyroid homogenates or not. There was no significant difference between the enzyme activity with LATS-IgG and that with normal IgG, while the activity was mostly inhibited by theophylline. These data are not consistent with the hypothesis that LATS acts as an antibody to phosphodiesterase.

scholarly journals In Vitro Effects of Different Combinations of Phytohormones on Callus Induction from Different Explants of Cabbage Brassica Oleracea Var. Capitata L. Seedlings

2021 ◽  
pp. 3476-3486
Author(s):  
Alaa. M. Hasan ◽  
Ekhlas. A.J. ElKaaby ◽  
Rakad. M.Kh. AL-Jumaily
Keyword(s):  
Brassica Oleracea ◽  
Callus Induction ◽  
Basal Medium ◽  
Culture Conditions ◽  
Control Treatment ◽  
Fresh Weight ◽  
Superior Result ◽  
Significant Difference ◽  
In Vitro Effects

    The leading purpose of this work is the development of efficient culture conditions to induce calli from cabbage (Brassica oleracea var. capitata L.) under in vitro conditions. The mature seeds were surface sterilized with combinations of different concentrations of ethanol and NaOCl in different time durations and  were germinated on MS basal medium. The results revealed that the best sterilization method of cabbage seeds was by using 70% ethanol for one minute, followed by 15 min in 2% (NaOCl). Seedlings were used as donor sources for hypocotyls, cotyledon leaves, true leaves, and shoot tip explants. These explants were cultured on different combinations of cytokinins (TDZ, BAP, Ad) and auxins (IAA, NAA, 2, 4-D) then implanted in Murashige and Skoog (MS) media. 4 weeks after culturing, a significant difference was found among the explants in response to plant hormones. The maximum percentage of callus induction (100%) was using the combinations of 1 BAP + 1 2, 4-D, 1 BAP + 1 NAA, and 1 BAP + 2 2,4-D mg. l-1. In addition, explants responses varied and the hypocotyls showed a superior result (85.71 %) as compared to other explants. For callus fresh weight, the combination of 0.22 TDZ + 79.9 Ad mg. l-1    had a significant effect, causing the highest fresh weight (0.2745g), while control treatment gave the lowest mean of 0.0066 g. Data showed that cotyledon explants were significantly superior in giving highest callus fresh weight with the mean of 0.1723 g. On the other hand, hypocotyl explants gave the lowest mean, reaching 0.1542 g.

168 EFFECT OF CYCLIC ADENOSINE MONOPHOSPHATE MODULATORS DURING OOCYTE IN VITRO MATURATION ON BOVINE EMBRYOS (Gyr×HOLSTEIN) QUALITY

2016 ◽  
Vol 28 (2) ◽  
pp. 214
Author(s):  
G. R. Leal ◽  
C. A. S. Monteiro ◽  
H. F. R. A. Saraiva ◽  
A. J. R. Camargo ◽  
P. M. S. Rosa ◽  
...  
Keyword(s):  
Lipid Content ◽  
In Vitro Maturation ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Control Group ◽  
Bovine Embryos ◽  
Tropical Conditions ◽  
Significant Difference ◽  
Number Of Cells

In vitro embryo production (IVP) is an important tool for cattle breeding. Brazilian dairy systems are based on Gyr × Holstein crossbreds, which integrates adaptability to tropical conditions and milk production. Quality determines the oocyte proportion that will develop to blastocyst stage, and although the lipid content is important in oocyte development, a high concentration in embryos is associated with cryotolerance reduction, making this a relevant issue for IVP systems. The in vitro maturation system (IVM) simulated physiological oocyte maturation (SPOM) mimics the physiological maturation events by using cyclic adenosine monophosphate (cAMP) modulators, which promote the increase of oocyte competence. Among the modulators, Forskolin has lipolytic properties. The aim of this study was to evaluate the effect of the SPOM system (Albuz 2010 Hum. Reprod. 25, 12) on bovine embryos (Gyr × Holstein) regarding their total number of cells (TNC) and lipid content. Oocytes were obtained by ovum pick-up from Gyr cows in 5 replications. After selection, they were randomly divided into 2 groups: SPOM (S) and control (C). The IVM lasted 24 h for group C (TCM 199 medium without FBS) in culture oven at 38.5°C, 5% CO2 in atmospheric air and high humidity. In the SPOM system, oocytes were in pre-IVM [TCM 199 medium + 100 µM Forskolin + 500 µM 3-isobutyl-1-methylxanthine (IBMX)] for 2 h and followed for extended IVM (TCM 199 medium + 20 µM cilostamide) for 28 h under the same conditions as control group. After IVM, oocytes were fertilised with semen from a single Holstein bull that was prepared by Percoll gradient method in Fert-TALP medium (Bioklone® Animal Reproduction, São Paulo, Brazil) for 22 h and transfered to culture droplets, where they remained for 7 days (n = 10–13 per group). The lipid content analysis was performed by staining with Oil red and the stained area fraction of each embryo was measured using software ImageJ (NIH, Bethesda, MD, USA). The TNC was measured after being stained with Hoechst 33342 and results were analysed by Student's t-test in Instat GraphPad program, with a 5% significance level. There was no significant difference (P > 0.05) between embryos from both groups on TNC (group S: 88.9 ± 28.0A; group C: 101.6 ± 29.1a) and lipid content (group S: 0.93 ± 12:18A; group C: ±0.15 to 0.96) analysis. Some studies have shown there is a beneficial effect on embryo quality when using this system; however, our results demonstrated that there was no effect on total number of cells using our conditions. Some authors have also demonstrated a reduction in embryo lipid content using Forskolin during in vitro culture. Our results suggest that the time of Forskolin exposure was not enough to ensure lipolytic action on the structures produced from oocytes (Gyr) treated in pre-IVM. It was concluded that the SPOM system had no effect on TNC and lipid content of Gyr/Holstein embryos. Financial support from FAPERJ and CAPES is acknowledged.

scholarly journals Effects of Homemade Nano-Hydroxyapatite and Olive Oil Paste on Remineralization of Early Caries Lesions

2022 ◽  
Author(s):  
Ayşe Dina Erdilek ◽  
Sevdiye Burke ◽  
Merve Şahin ◽  
Ata Efes ◽  
Begüm Güray Efes
Keyword(s):  
Olive Oil ◽  
Sodium Fluoride ◽  
Fluoride Toothpaste ◽  
Enamel Caries ◽  
Diagnodent Pen ◽  
Significant Difference ◽  
In Vitro Effects ◽  
New Generation ◽  
Caries Lesions

Nano-hydroxyapatite (nHAP) particles are a new generation of materials reported to remineralize enamel lesions. The purpose we aimed was to compare the in vitro effects of fluoride gel, sodium fluoride toothpaste, and homemade nHAP paste on remineralizing artificial early enamel caries. Methods:  Incipient caries were induced in 21 extracted, sound premolar teeth by storing each specimen in a demineralization solution for 72 hours, followed by pH cycling. The samples (n= 7, each) were then treated with 2% neutral fluoride gel, 0.25% sodium fluoride toothpaste, or homemade nHAP paste, comprising a mixture of nHAP powder and olive oil. After demineralization and remineralization, the results were compared using the DIAGNOdent pen (KaVo, Germany). The data were statistically analyzed using paired t-tests and a one-way ANOVA test. Outcomes: The degree of demineralization in each of the three groups (fluoride gel group, 15.71; sodium fluoride dentifrice group, 15.28; nHAP paste group, 16.71) was significantly elevated compared to baseline (3, 2.5, 2.28, respectively); however, no significant difference was observed between the remineralization readings in each of the three groups (6, 7, 5.5, respectively) (p > 0.05). In conclusion, we concluded that the homemade nHAP paste had a beneficial effect on the remineralization of initial enamel caries lesions.

Cyclic AMP phosphodiesterase activity in the hearts of trained rats

1983 ◽  
Vol 61 (9) ◽  
pp. 1017-1024
Author(s):  
Warren K. Palmer ◽  
Sylvia Doukas
Keyword(s):  
Enzyme Activity ◽  
Cyclic Amp ◽  
Total Concentration ◽  
Chelating Agent ◽  
Phosphodiesterase Activity ◽  
Cyclic Amp Phosphodiesterase ◽  
Rat Hearts ◽  
Elevated Activity ◽  
And Control

Running exercise trained rats at either 60 or 76% of their [Formula: see text] caused myocardial cyclic AMP phosphodiesterase (PDE) activity to be increased above control levels for at least 24 h following work. Neither training nor the exercise had any effect on the total concentration of calmodulin in heart tissues. The affinity of PDE for cyclic AMP was not changed by the exercise or training. The chelating agent, EGTA, had the same influence on PDE activity regardless of whether it was present in assays of control or exercised heart extract. Km and EGTA results suggest that calcium-bound calmodulin does not account for the higher PDE activity in the hearts of exercised rats. Supernatants from hearts homogenized in the presence of charcoal, to remove nucleotides from the extract, did not eliminate the exercise-associated increase in PDE activity. These results suggest that the elevated activity was not caused by an in vitro nucleotide activation. Preincubation of the enzyme from exercised and control rat hearts with snake venom activated PDE when assays were performed with the low concentration of cyclic AMP (1 μM). Moreover, the activity reached in the extract of exercisers (23.3 pmol∙100 μL−1∙min−1) was significantly greater than the activity found in control hearts (17.59 pmol∙100 μL−1∙min−1). Exercise increases PDE activity in the myocardium of trained rats. The results presented suggest that the increased PDE activity resulting from exercise is not dependent upon exercise intensity when the work is in excess of 60% of [Formula: see text]. In addition, the data obtained using indirect probes suggest that the increased enzyme activity was not caused by metabolites, endogenous nucleotides, or calmodulin changes in the hearts of exercised animals.

In-vitro effects of mammalian and amphibian prolactins on hepatic vitellogenin synthesis in Rana esculenta

1993 ◽  
Vol 137 (3) ◽  
pp. 383-389 ◽  
Author(s):  
O. Carnevali ◽  
G. Mosconi ◽  
K. Yamamoto ◽  
T. Kobayashi ◽  
S. Kikuyama ◽  
...  
Keyword(s):  
Rana Catesbeiana ◽  
Direct Action ◽  
Rana Esculenta ◽  
Amino Acid Sequences ◽  
Significant Difference ◽  
Vitellogenin Synthesis ◽  
In Vitro Effects ◽  
Ovine Prolactin ◽  
High Degree

ABSTRACT Male and female Rana esculenta liver was induced in an in-vitro system by homologous and Rana catesbeiana pituitary to synthesize and release vitellogenin, a lipoglycophosphoprotein precursor of yolk proteins, lipovitellins and phosvitins, in oviparous vertebrates. In the present experiments, the action of prolactin on hepatic vitellogenin synthesis and release was investigated, using ovine prolactin and Rana catesbeiana prolactin. The effects of prolactin on hepatic vitellogenin synthesis displayed different trends related to sex; male liver was found to be more responsive than female liver to both ovine and frog prolactin; moreover, the response to prolactin was dose-related (r = 0·998; P <0·05) in male but not in female liver. In both sexes, a high degree of seasonality in the responsiveness of the liver was found, since the vitellogenin levels induced by prolactin during the winter phase were significantly (P < 0·001) higher than those produced during the summer phase. Thus, there was no significant difference between the action of ovine and frog prolactin on vitellogenin synthesis; in fact, mammalian prolactins are structurally similar with regard to nucleotide and amino acid sequences. The direct action of prolactin on hepatic vitellogenin synthesis in the frog Rana esculenta is discussed, on the basis of the role played by prolactin as an important growth modulatory hormone in fetal and adult tissues. Journal of Endocrinology (1993) 137, 383–389

scholarly journals METAL-INDUCED PROTEIN DENATURATION: REGULARITIES, PATHOLOGICAL MANIFESTATIONS, AND IN VITRO MODELING

2021 ◽  
Vol 127 (4) ◽  
pp. 48-54
Author(s):  
Tetiana Popovych ◽  
Yaroslav Kizim ◽  
Yaroslav Kizim ◽  
Natalia Obernikhina ◽  
Natalia Voroshylova
Keyword(s):  
Magnetic Resonance Imaging ◽  
Metal Ions ◽  
Protein Denaturation ◽  
Resonance Imaging ◽  
Nickel Ions ◽  
Ph Values ◽  
Significant Difference ◽  
In Vitro Effects ◽  
Allergic Contact

the ability of various metal ions to form complexes with proteins leads to the denaturation of the latter and the development of immune response. Such hapten effects cause the well-known phenomenon of nickel-allergic contact dermatitis. No less typical are side effects of gadolinium compounds, that are used as contrasts for magnetic resonance imaging, but cause the development of fibrosis. In both cases an important role belongs to the interaction of metal ions with collagen structures. The aim of our study was to compare in vitro effects of copper and nickel ions on destabilized products of collagen cleavage. Significant difference between these metals in their ability to induce aggregation at close to physiological pH values was shown. The influence on the aggregative process of the acidification of the medium was revealed. It was shown that destabilization of protein structure leads to the formation of highly stabilized β-stacked protein aggregates. Comparison of the obtained experimental data with the  literature ones makes it possible to approach the understanding of individual mechanisms of toxic effects of metal ions on the human body.

scholarly journals In vitro effects of synthetic muscimol and an extract from Amanita muscaria on human recombinant MAOB enzyme

Pharmacia ◽  
2021 ◽  
Vol 68 (1) ◽  
pp. 147-150
Author(s):  
Maria Voynova ◽  
Aleksandar Shkondrov ◽  
Ilina Krasteva ◽  
Magdalena Kondeva-Burdina
Keyword(s):  
Enzyme Activity ◽  
Amanita Muscaria ◽  
In Vitro Effects

The effects of synthetic muscimol and an extract from Amanita muscaria, containing this compound on the activity of human recombinant MAOB enzyme (hMAOB) were studied. Muscimol had statistically significant inducing effect on hMAOB at concentrations 0.25–5 μM, while A. muscaria extract did not influence the enzyme activity at all.

236 EFFECT OF CYCLIC ADENOSINE MONOPHOSPHATE MODULATOR REGULATORS IN ASSOCIATION WITH BMP15 ON BOVINE EMBRYO DEVELOPMENT IN VITRO

2015 ◽  
Vol 27 (1) ◽  
pp. 207
Author(s):  
M. F. Machado ◽  
M. F. G. Nogueira ◽  
R. B. Gilchrist ◽  
M. L. Sutton-McDowall ◽  
D. G. Mottershead ◽  
...  
Keyword(s):  
Embryo Development ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Differential Staining ◽  
Bovine Embryo ◽  
Oocyte Competence ◽  
Significant Difference

BMP15 is a promising peptide to improve oocyte competence; also, addition of cyclic adenosine monophosphate modulator (cAMP) regulators prevents spontaneous maturation in vitro and promotes embryo development. We aimed to assess embryo development after prematuration [pre-in vitro maturation (IVM)] with IBMX and Forskolin (FSK) and maturation in the presence or absence of a purified pro mature region of BMP15. Immature cumulus-oocyte complexes (COC) were cultured in vitroMat (IVF Vet Solutions, Adelaide, Australia) plus 4 mg mL–1 fatty acid free-BSA and rhFSH (0.1 IU mL–1), then divided into the following treatment groups: 1) spontaneous IVM: 24 h of IVM; 2) spontaneous IVM + BMP15: 24 h of IVM in the presence of BMP15 (100 ng mL–1); 3) Pre 2 h: pretreatment with IBMX (500 µM; Sigma-Aldrich) and FSK (100 µM; Sigma-Aldrich) for 2 h following 24 h maturation; and 4) Pre 2 h + BMP15: pretreatment with IBMX and FSK for 2 h following 24 h maturation in the presence of BMP15 (100 ng mL–1). After maturation, oocytes were inseminated and zygotes were cultured for 5 days in VitroCleave (IVF Vet Solutions, Adelaide, Australia) and transferred into VitroBlast (IVF Vet Solutions, Adelaide, Australia) until blastocyst assessment (Days 7 and 8). Zona-intact embryos were retrieved to assess differential staining of trophectoderm and inner cell mass. Data were transformed into a logarithm and analysed by 1-way ANOVA and post hoc least significant difference using SigmaStat software (SPSS Inc., San Jose, CA, USA; P < 0.05). There was no difference among groups on cleavage rates or blastocyst rates at Day 7; however, both Pre 2 h treatments increase hatched blastocyst rates at Day 8 of embryo development (Table 1). Supplementation with BMP15 increased total blastocyst rates at Day 8, regardless of pretreatment with IBMX+FSK (Table 1). Our data demonstrate that embryos from oocytes matured in the presence of BMP15 or pretreated with IBMX+FSK increase trophectoderm and total cell numbers; however, no differences were observed for inner cell mass. We conclude that Pre 2 h treatment or BMP15 increase embryo development; however, no effect of cAMP regulators in association with BMP15 on embryo development was observed. Table 1.Embryo development Supported by FAPESP (project numbers: 2012/1073-8; 2013/12960-9; 2013/05083-1; 2012/50533-2).

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