scholarly journals Hormonal stimulation in the exocrine pancreas results in coordinate and anticoordinate regulation of protein synthesis.

1984 ◽  
Vol 99 (5) ◽  
pp. 1569-1574 ◽  
Author(s):  
J Schick ◽  
H Kern ◽  
G Scheele

24-h intravenous caerulein infusion studies in the rat were combined with in vitro amino acid incorporation studies followed by high-resolution separation of proteins by two-dimensional isoelectric focusing and SDS gel electrophoresis to study the extent to which persistent changes in the biosynthesis of exocrine pancreatic proteins are regulated by cholecystokinin-like peptides. Beginning in the third hour of optimal hormone infusion at 0.25 microgram kg-1 h-1, changes were observed in the synthetic rates of 12 proteins, which progressed over the course of the 24-h study. Based on coordinate response patterns, exocrine proteins could be classified into four distinct groups. Group I (trypsinogen forms 1 and 2) showed progressive increases in synthetic rates reaching a combined 4.3-fold increase over control levels. Group II (amylase forms 1 and 2) showed progressive decreases in synthesis to levels 7.1- and 14.3-fold lower than control levels, respectively. Group III proteins (ribonuclease, chymotrypsinogen forms 1 and 2, procarboxypeptidase forms A and B, and proelastase 1) showed moderate increases in synthesis, 1.4-2.8-fold, and group IV proteins (trypsinogen 3, lipase, proelastase 2, and unidentified proteins 1-4) did not show changes in synthesis with hormone stimulation. Regulation of protein synthesis in response to caerulein infusion was specific for individual isoenzymic forms in the case of both trypsinogen and proelastase. The ratio of biosynthetic rates of trypsinogen forms 1 + 2 to amylase forms 1 + 2 increased from a control value of 0.56 to 24.4 after 24 h of hormonal stimulation (43.5-fold increase). Biosynthetic rates for an unidentified protein (P23) with an Mr = 23,000 and isoelectric point of 6.2 increased 14.2-fold, and the ratio of synthesis of P23 to amylase 2 increased 200-fold during caerulein infusion. During hormone stimulation the anticoordinate response in the synthesis of pancreatic glycosidases (decreased synthesis) and serine protease zymogens (increased synthesis) explain previous observations that showed little change in rates of total protein synthesis under similar conditions.

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Agnieszka Ścibior ◽  
Dorota Gołębiowska ◽  
Irmina Niedźwiecka

The protective effect of magnesium as magnesium sulfate (MS) on sodium-metavanadate- (SMV-) induced lipid peroxidation (LPO) underin vivoandin vitroconditions was studied. The 18-week SMV intoxication (Group II, 0.125 /mL) enhanced spontaneous malondialdehyde (MDA) generation in rat liver, compared with the control (Group I) and MS-supplemented animals (Group III, 0.06 /mL). Coadministration of SMV with MS (Group IV, SMV-MS) caused a return of the MDA level to the control value range. The effect seems to result from the -independent action and its antagonistic interaction with . Thein vitrotreatment of liver supernatants (LS) obtained from all the tested animals groups with selected exogenous concentrations of or exhibited enhanced MDA production, compared with spontaneously formed MDA. It also showed -stimulating effect on LPO (LS I, Group I) and revealed that the changes in the MDA generation in LS IV (Group IV) might have resulted from the synergistic interactions of with and and from the antagonistic interactions of with and . The findings allow a suggestion that adequate Mg intake for a specific period in the conditions of SMV exposure may prevent V-induced LPO in the liver.


1976 ◽  
Vol 35 (02) ◽  
pp. 350-357 ◽  
Author(s):  
Hana Bessler ◽  
Galila Agam ◽  
Meir Djaldetti

SummaryA three-fold increase of protein synthesis by human platelets during in vitro phagocytosis of polystyrene latex particles was detected. During the first two hours of incubation, the percentage of phagocytizing platelets and the number of latex particles per platelet increased; by the end of the third hour, the first parameter remained stable, while the number of latex particles per cell had decreased.Vincristine (20 μg/ml of cell suspension) inhibited platelet protein synthesis. This effect was both time- and dose-dependent. The drug also caused a decrease in the number of phagocytizing cells, as well as in their phagocytotic activity.


1991 ◽  
Vol 260 (3) ◽  
pp. H730-H734 ◽  
Author(s):  
P. N. McWilliam ◽  
T. Yang

The action of electrically evoked activity in somatic afferent fibers on the sensitivity of the baroreceptor reflex was examined in decerebrate cats. The sensitivity of the reflex was expressed as the difference between the maximum prolongation of R-R interval in response to carotid sinus pressure elevation and the mean of 10 R-R intervals immediately before pressure elevation. The control value of R-R interval prolongation was 192 +/- 50 ms. Stimulation (10 Hz) of group I and II fibers of the right peroneal nerve (evoked volleys recorded from the sciatic nerve) had no effect on R-R interval prolongation (171 +/- 45 ms). Recruitment of group III fibers (10 Hz) conducting at 23.6 +/- 0.65 m/s reduced the prolongation of R-R interval to 52 +/- 14 ms. Recruitment of group IV fibers (10 Hz) conducting less than 2.5 m/s further reduced the prolongation of R-R interval to 1.0 +/- 8.0 ms. It is concluded that the inhibition of the cardiac vagal component of the baroreceptor reflex produced by electrical stimulation of the peroneal nerve is mediated by afferent fibers of groups III and IV.


2006 ◽  
Vol 17 (4) ◽  
pp. 300-305 ◽  
Author(s):  
Sérgio Lima Santiago ◽  
José Carlos Pereira ◽  
Ana Christina Bonato Figueiredo Martineli

This study evaluated the influence of time after application of oxalate solutions in reducing dentin hydraulic conductance. Fifty dentin discs were obtained from extracted human third molars and assigned to 5 groups (n=10), according to the desensitizing agent used: Group I: OxaGel; Group II: experimental agent DD-1: Group III: experimental agent DD-2. In Groups IV and V, a placebo gel and deionized water were used as control, respectively. The agents were applied for 3 min, washed out and the hydraulic conductance was measured immediately and at 5-, 15- and 30-min intervals, and after acid etching. Data were analyzed statistically by two-way ANOVA and Duncan's test at 5% significance level. Groups I, II and III did not differ significantly from each other in any of the time intervals (p>0.05). Likewise, Groups IV and V were statistically similar to each other (p>0.05). The active agents reduced significantly dentin permeability in comparison to control groups (p<0.05). Dentin permeability measured in vitro decreased significantly with time regardless of the agent applied (either active or control agents). The results of Group V, in which no dentin desensitizing agent was employed, indicates that the assessment of dentin permeability by this method must be interpreted with caution.


2012 ◽  
Vol 17 (4) ◽  
pp. 1-7 ◽  
Author(s):  
Roberto Hideo Shimizu ◽  
Karlos Giovani Grando ◽  
Isabela Almeida Shimizu ◽  
Augusto Ricardo Andriguetto ◽  
Ana Cláudia Moreira Melo ◽  
...  

OBJECTIVE: This in vitro study was designed to evaluate the shear bond strength (SBS) of orthodontic metal brackets bonded by direct and indirect techniques. METHODS: Thirty healthy human maxillary premolar teeth were used. The teeth were divided into three groups of 10 teeth each: Group I - indirect bonding with SondhiTM Rapid-Set system (3M/Unitek), Group II - indirect bonding with TransbondTM XT adhesive system (3M/Unitek) and Group III - direct bonding with TransbondTM XT adhesive system (3M/Unitek). After bonding and obtaining the specimens for the study, the specimens were subjected to SBS testing in a universal testing machine (Emic, model DL-500). The Kolmogorov-Smirnov test was applied to ascertain that the data had a normal distribution and the Bartlett test to check whether there was homogeneity of variance. One-factor analysis of variance was performed and, subsequently, Tukey's test for paired means. A 5% significance level was adopted. RESULTS: The results of Group I were 67.6 (N) and 5.9 (MPa); Group II, 68.9 (N) and 6.1 (MPa) and Group III (control), 92.5 (N) and 8.1 (MPa). CONCLUSION: It can therefore be concluded that the means for Group III were significantly higher compared with Groups I and II in both Newton (N) and Megapascal (MPa) values. The means attained by the indirect bonding technique used in Groups I and II, however, exhibited no statistically significant differences.


2016 ◽  
Vol 3 (1) ◽  
pp. 42
Author(s):  
Diyah Fatmasari ◽  
Lanny Sunarjo

Background: The role of fluoride in preventing tooth decay both for children and adult has been acknowledged internationally. There are several types of fluoride modalities either topically or systemic way. In Indonesia the modalities used to apply are fluoride tablet, fluocol solution and fluoride containing toothpaste. The purpose of this research is to find the effectiveness of fluoride modalities.Method: The study design was quasy experimental with 40 extracted teeth (Premolar teeth). The teeth divided into four groups D group I soaked on tablet fluor, Group II ; soaked on fluocol solution, Group III soaked on fluoride tooth paste and group IV soaked on Mill J (Aquadest/ Control solution). Fluoride concentration before and after soaking was determined using Spectrophotometer UV-Vis. Fluoride absorption was determined by the reduction of fluoride concentration after soaking.Result: Research result shown that the highest fluoride absorption was on soaking in fluoride tablet, followed by soaking on fluocol and tooth paste (mean fluoride absorption was 0,32; 0,08 and 0,04 ppm). Anova test shown significance level was 0,000.Conclusion: there were a significance of fluoride absorption on soaking in tablet fluoride, fluocol solution and toothpaste. The mechanism of fluoride regimens shown different fluoride absorption.


2020 ◽  
Vol 5 (3) ◽  
pp. 92-97
Author(s):  
Siska ◽  
Diene Roufiani ◽  
Ema Dewanti

Anaphylaxis is the most common allergic reaction triggered by allergens such as insect poisons, food, and drugs through skin contact, injection, or inhalation. In vitro previous research showed that strawberries fruit have activity as antioxidant, anticancer, anti-inflammation, and anti-allergic. The research aimed to determine the antianaphylaxis strawberry fruit extract in mice (Balb/C strain) with ovalbumin-induced.  Twenty-four Balb/C strain mice were divided into six groups (n=4). Group I and II as a normal and control group. Group III till VI as a treatment group was given cetirizine dose 0.042 mg/20 g BW and strawberry extract doses 0,68; 1,36; and 2,72 mg/20 g BW, respectively. This research showed that 70 % of ethanol extract of strawberries fruit have antiallergic activity in response to active cutaneous anaphylaxis. 70% ethanol extract of strawberries doses 2.72 mg/20 g BW had similar antiallergic activity compare with cetirizine. The conclusion of this study showed that strawberries fruit extract could be developed as an alternative medicine to anti-anaphylaxis or anti-allergic.


2004 ◽  
Vol 16 (2) ◽  
pp. 157 ◽  
Author(s):  
S.J. Rzucidlo ◽  
S. Arat ◽  
S.L. Stice

The activation of oocytes is one of the most important steps for a successful cloning, and chemicals used for activation can affect the viability of cloned offspring. Therefore, some of them may be omitted for activation to eliminate their possible detrimental effect on nuclear transfer (NT) embryos. The objective of this study was to examine the effect of calcium ionophore (CaI, A23187, Sigma, St. Louis, MO, USA) and cytochalasin D (CD) on activation and in vitro development of nuclear transfer units derived from bovine granulosa cells (GCs) treated with the cell cycle inhibitor, roscovitine. Bovine oocytes isolated from slaughterhouse ovaries were matured in TCM199 supplemented with fetal bovine serum (FBS), sodium pyruvate, penicillin/streptomycin, rIGF-1, bFSH, and bLH. GCs were isolated from ovarian follicles and cultured in DMEM-F12 supplemented with 10% FBS at 37°C in 5% CO2 in air. Prior to NT, donor cells were exposed to 15mM roscovitine for 24 hours and small cells were used for NT. A single cell was inserted into the perivitelline space of the enucleated oocyte. Oocyte-cell couples were fused using a 20μs DC pulse of 40V/150μm. Two hours after fusion, NT units were assigned into four groups and activated by CaI (5μM for 10min.), and then incubated with cycloheximide (CHX, 10μgmL−1)+CD (2.5μgmL−1) for 1h, followed by CHX alone (without CD) for 5h (Group I) or CaI (for 10min.), followed by CHX alone for 6h (Group II). In the Group III, NT units were activated by CHX (10μgmL−1)+CD (2.5μgmL−1) for 1h, followed by CHX for 5h, and Group IV, CHX alone for 6h. The base activation medium was TCM199 with 1% FBS for CaI and 10% FBS for CHX and CD. After activation, NT units were cultured for 7 days in BARC medium. Differences in activation, cleavage and blastocyst formation rates among treatments were analyzed by one-way ANOVA after arcsin square transformation. The results are summarized in Table 1. Our data showed that CaI and CD did not affect the activation and in vitro development of NT embryos derived from roscovitine-treated GCs. It suggests that both chemicals may be redundant during cloning procedure. This study was supported by a grant from ProLinia, Inc and TUBITAK, Turkey (VHAG-1908-102V048). Table 1 In vitro development of NT embryos in different activation treatments


2013 ◽  
Vol 14 (1) ◽  
pp. 56-60 ◽  
Author(s):  
S Nagalaxmi Reddy ◽  
DN Jayashankar ◽  
Mohanthomas Nainan

ABSTRACT Aim Aim of this study was to compare class II composite restoration using flowable composites as lining with various thickness and curing techniques by evaluating cervical marginal microleakage. Materials and methods Fifty intact molars, each prepared with two box-only class II cavities, were randomly divided into five groups: Group I, P60 filling alone; group II, ultrathin flowable composite lining (0.5-1mm) cocured with overlying composite; group III, thin lining (1-1.5) cocured with overlying composite; group IV, ultrathin lining (0.5-1 mm) precured and group V, thin lining (1-1.5) precured. The teeth were then thermocycled for 1500 cycles (between 5 and 60 °C) and immersed in dye for 24 hours. Cervical microleakage was measured as the extent of dye penetration. Results Cocured specimens (groups II and III) showed least microleakage and control specimens (group I) showed maximum microleakage. On comparison of curing techniques, cocured specimens (groups II and III) showed less microleakage than precured (groups IV and V). On comparison of lining thickness and type of curing, group IV showed less microleakage than group V. Groups II and III were statistically not significant. Conclusion It was concluded from the results that ultrathin cocured flowable composite lining specimens improved the marginal sealing with decreased microleakage. Clinical significance In this study, the application of additional flowable composite lining with various thicknesses presented different influences in marginal quality of class II box only composite restorations. A new technique applying an ultrathin flowable composite lining with cocuring technique improved the marginal sealing with decreased microleakage. Restorations with thin lining presented reduced marginal integrity after thermocycling. How to cite this article Reddy SN, Jayashankar DN, Nainan M, Shivanna V. The Effect of Flowable Composite Lining Thickness with Various Curing Techniques on Microleakage in Class II Composite Restorations: An in vitro Study. J Contemp Dent Pract 2013;14(1):56-60.


2017 ◽  
Vol 9 (1) ◽  
pp. 23-29
Author(s):  
Bijo Kurian

BACKGROUND AND OBJECTIVES: This study evaluated and compared the antimicrobial efficacy and minimal inhibitory concentration (MIC) of chlorhexidine 0.12% and extracts of aloe vera and mushroom against Streptococcus mutans and lactobacillus. MATERIALS & METHODOLOGY: The agar disc diffusion and broth micro dilution method was used to check the antimicrobial activity of 0.12% chlorhexidine and aqueous extracts of two medicinal plants. The test samples were divided as follows- Streptococcus mutans, group I: chlorhexidine, group II: Aloe vera and group III: Mushroom. Lactobacillus, Group I: chlorhexidine, group II: Aloe vera extract and group III: Mushroom extract. The zone of inhibition and MIC values were tabulated and the data was statistically analyzed using ANOVA and Bonferroni post- hoc tests. RESULTS: Chlorhexidine shows maximum antibacterial action against Streptococcus mutans and lactobacillus followed by mushroom extract and aloe veraextracts with the zone of inhibition of (20.3mm/ 24.13), (17.03/ 16.05), (14.09/14.26) respectively. Both the extracts had MIC value of 80µg/ ml and chlorhexidine was 40µg/ml. CONCLUSION: Within the limitations of this in- vitro study, it can be concluded that all the herbal extracts tested in this study demonstrated antibacterial activity against MS and lactobacillus. Chlorhexidine showed maximum antibacterial action against Streptococcus mutans and lactobacillus followed by mushroom extract and then aloe veraextracts with the zone of inhibition of (20.3mm/24.13), (17.03/ 16.05), (14.09/14.26) respectively. Herbal products have potent antimicrobial activity that can be looked at as an alternative to chlorhexidine. However, further in vitro and long-term in vivo studies are recommended to confirm and correlate the findings of this study clinically.


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