scholarly journals THE DEVELOPMENT OF THE DORSAL AND VENTRAL MAMMALIAN PANCREAS IN VIVO AND IN VITRO

1970 ◽  
Vol 47 (1) ◽  
pp. 235-246 ◽  
Author(s):  
Brian S. Spooner ◽  
Bernt T. Walther ◽  
William J. Rutter

The origin, morphogenesis, and biochemical differentiation of the dorsal and ventral pancreas of the rat embryo have been investigated in order to ascertain the similarities and dissimilarities between the two lobes. We have utilized a culture system in which the primitive gut gives rise to a number of differentiated organs, including the dorsal and ventral pancreas. The two pancreases do not undergo fusion in these cultures, thus allowing independent analyses of the two lobes for comparison with in vivo results. The dorsal pancreas first appeared at the 23–25 somite stage while the ventral pancreas appeared approximately 12 hr later at the 29–30 somite stage. Guts from embryos as young as 12 somites were capable of developing both pancreases in vitro. In spite of the 12 hr difference between the times of their appearance, the dorsal and ventral pancreases exhibited identical patterns of morphological and biochemical differentiation. The two lobes contained the same exocrine enzymes and hormones, at similar levels, differing only in their glucagon content, the dorsal pancreas possessing a fivefold higher glucagon specific activity. The implications of these results are discussed.

1995 ◽  
Vol 73 (05) ◽  
pp. 805-811 ◽  
Author(s):  
Yasuo Takahashi ◽  
Yoshitaka Hosaka ◽  
Hiromi Niina ◽  
Katsuaki Nagasawa ◽  
Masaaki Naotsuka ◽  
...  

SummaryWe examined the anticoagulant activity of two major molecules of soluble thrombomodulin purified from human urine. The apparent molecular weights of these urinary thrombomodulins (UTMs) were 72,000 and 79,000, respectively. Both UTMs showed more potent cofactor activity for protein C activation [specific activity >5,000 thrombomodulin units (TMU)/mg] than human placental thrombomodulin (2,180 TMU/mg) and rabbit lung thrombomodulin (1,980 TMU/mg). The UTMs prolonged thrombin-induced fibrinogen clotting time (>1 TMU/ml), APTT (>5 TMU/ml), TT (>5 TMU/ml) and PT (>40 TMU/ml) in a dose-dependent fashion. These effects appeared in the concentration range of soluble thrombomodulins present in human plasma and urine. In the rat DIC model induced by thromboplastin, administration of UTMs by infusion (300-3,000 TMU/kg) restored the hematological abnormalities derived from DIC in a dose-dependent fashion. These results demonstrate that UTMs exhibit potent anticoagulant and antithrombotic activities, and could play a physiologically important role in microcirculation.


1982 ◽  
Vol 47 (03) ◽  
pp. 244-248 ◽  
Author(s):  
D P Thomas ◽  
Rosemary E Merton ◽  
T W Barrowcliffe ◽  
L Thunberg ◽  
U Lindahl

SummaryThe in vitro and in vivo characteristics of two oligosaccharide heparin fragments have been compared to those of unfractionated mucosal heparin. A decasaccharide fragment had essentially no activity by APTT or calcium thrombin time assays in vitro, but possessed very high specific activity by anti-Factor Xa assays. When injected into rabbits at doses of up to 80 ¼g/kg, this fragment was relatively ineffective in impairing stasis thrombosis despite producing high blood levels by anti-Xa assays. A 16-18 monosaccharide fragment had even higher specific activity (almost 2000 iu/mg) by chromogenic substrate anti-Xa assay, with minimal activity by APTT. When injected in vivo, this fragment gave low blood levels by APTT, very high anti-Xa levels, and was more effective in preventing thrombosis than the decasaccharide fragment. However, in comparison with unfractionated heparin, the 16-18 monosaccharide fragment was only partially effective in preventing thrombosis, despite producing much higher blood levels by anti-Xa assays.It is concluded that the high-affinity binding of a heparin fragment to antithrombin III does not by itself impair venous thrombogenesis, and that the anti-Factor Xa activity of heparin is only a partial expression of its therapeutic potential.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Changpeng Wang ◽  
Siwei Zhang ◽  
Yuefei Zou ◽  
Hongzhao Ma ◽  
Donglang Jiang ◽  
...  

Abstract Background Some neuropsychological diseases are associated with abnormal thiamine metabolism, including Korsakoff–Wernicke syndrome and Alzheimer’s disease. However, in vivo detection of the status of brain thiamine metabolism is still unavailable and needs to be developed. Methods A novel PET tracer of 18F-deoxy-thiamine was synthesized using an automated module via a two-step route. The main quality control parameters, such as specific activity and radiochemical purity, were evaluated by high-performance liquid chromatography (HPLC). Radiochemical concentration was determined by radioactivity calibrator. Metabolic kinetics and the level of 18F-deoxy-thiamine in brains of mice and marmosets were studied by micro-positron emission tomography/computed tomography (PET/CT). In vivo stability, renal excretion rate, and biodistribution of 18F-deoxy-thiamine in the mice were assayed using HPLC and γ-counter, respectively. Also, the correlation between the retention of cerebral 18F-deoxy-thiamine in 60 min after injection as represented by the area under the curve (AUC) and blood thiamine levels was investigated. Results The 18F-deoxy-thiamine was stable both in vitro and in vivo. The uptake and clearance of 18F-deoxy-thiamine were quick in the mice. It reached the max standard uptake value (SUVmax) of 4.61 ± 0.53 in the liver within 1 min, 18.67 ± 7.04 in the kidney within half a minute. The SUV dropped to 0.72 ± 0.05 and 0.77 ± 0.35 after 60 min of injection in the liver and kidney, respectively. After injection, kidney, liver, and pancreas exhibited high accumulation level of 18F-deoxy-thiamine, while brain, muscle, fat, and gonad showed low accumulation concentration, consistent with previous reports on thiamine distribution in mice. Within 90 min after injection, the level of 18F-deoxy-thiamine in the brain of C57BL/6 mice with thiamine deficiency (TD) was 1.9 times higher than that in control mice, and was 3.1 times higher in ICR mice with TD than that in control mice. The AUC of the tracer in the brain of marmosets within 60 min was 29.33 ± 5.15 and negatively correlated with blood thiamine diphosphate levels (r = − 0.985, p = 0.015). Conclusion The 18F-deoxy-thiamine meets the requirements for ideal PET tracer for in vivo detecting the status of cerebral thiamine metabolism.


Biology ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 6
Author(s):  
Palaniselvam Kuppusamy ◽  
Dahye Kim ◽  
Ilavenil Soundharrajan ◽  
Inho Hwang ◽  
Ki Choon Choi

A co-culture system allows researchers to investigate the complex interactions between two cell types under various environments, such as those that promote differentiation and growth as well as those that mimic healthy and diseased states, in vitro. In this paper, we review the most common co-culture systems for myocytes and adipocytes. The in vitro techniques mimic the in vivo environment and are used to investigate the causal relationships between different cell lines. Here, we briefly discuss mono-culture and co-culture cell systems and their applicability to the study of communication between two or more cell types, including adipocytes and myocytes. Also, we provide details about the different types of co-culture systems and their applicability to the study of metabolic disease, drug development, and the role of secretory factors in cell signaling cascades. Therefore, this review provides details about the co-culture systems used to study the complex interactions between adipose and muscle cells in various environments, such as those that promote cell differentiation and growth and those used for drug development.


2020 ◽  
Vol 45 (5) ◽  
pp. 631-637
Author(s):  
Cansu Ozel-Tasci ◽  
Gozde Pilatin ◽  
Ozgur Edeer ◽  
Sukru Gulec

AbstractBackgroundFunctional foods can help prevent metabolic diseases, and it is essential to evaluate functional characteristics of foods through in vitro and in vivo experimental approaches.ObjectiveWe aimed to use the bicameral cell culture system combined with the in vitro digestion to evaluate glucose bioavailability.Materials and methodsCake, almond paste, and pudding were modified by adding fiber and replacing sugar with sweeteners and polyols. Digestion process was modeled in test tubes. Rat enterocyte cells (IEC-6) were grown in a bicameral cell culture system to mimic the physiological characteristics of the human intestine. The glucose bioaccessibility and cellular glucose efflux were measured by glucose oxidase assay.Results and discussionThe glucose bioaccessibilities of modified foods were significantly lower (cake: 2.6 fold, almond paste: 9.2 fold, pudding 2.8 fold) than the controls. Cellular glucose effluxes also decreased in the modified cake, almond paste, and pudding by 2.2, 4, and 2 fold respectively compared to their controls.ConclusionOur results suggest that combining in vitro enzymatic digestion with cell culture studies can be a practical way to test in vitro glucose bioaccessibility and bioavailability in functional food development.


2011 ◽  
Vol 40 (1) ◽  
pp. 124-128
Author(s):  
Sabine Wohlres-Viana ◽  
Mariana Cortes Boite ◽  
João Henrique Moreira Viana ◽  
Marco Antonio Machado ◽  
Luiz Sérgio de Almeida Camargo

The objectives of this work were to identify and to evaluate possible differences on gene expression of aquaporins and Na/K-ATPases transcripts between embryos in vivo and in vitro produced. For each group, 15 blastocysts distributed in three pools were used for RNA extraction followed by amplification and reverse transcription. The resulting cDNAs were submitted to Real-Time PCR, using the GAPDH gene as endogenous control. It was not possible to identify AQP1 transcripts. Relative expression of AQP3 (1.33 ± 0.78) and AQP11 (2.00 ± 1.42) were not different in blastocysts in vitro and in vivo produced. Na/K-ATPase α1 gene (2.25 ± 1.07) was overregulated whereas Na/K-ATPase β2 transcripts 0.40 ± 0.30) did not differ among blastocysts produced in vitro from those produced in vivo. Transcripts for gene AQP1 are not present in bovine blastocysts. In vitro culture system does not alter expression of genes AQP3, AQP11 and Na/K-ATPase β2 genes, however, it affects expression of Na/K-ATPase α1.


2016 ◽  
Vol 26 (1) ◽  
pp. 15-23
Author(s):  
Saima Khan ◽  
Meenu Katoch ◽  
Sharada Mallubhotla ◽  
Suphla Gupta ◽  
Manju Sambyal ◽  
...  

The potential of various culture lines of Atropa acuminata were investigated for resourcing acid phosphatase (ACP) (3.1.3.2). Crude enzyme extract comprised of a mixture of four isoforms, distinguishable by polyacrylamide gel electrophoresis (PAGE) with molecular weight ranging from 39 to 215 kDa. In vitro regenerated proliferative shoots, callus and roots showed higher specific activity (2.49, 3.41, 2.91 U/mg protein, respectively) as compared to in vivo grown plants (0.71 U/mg protein). ACP activity in root cultures increased progressively up to 4.6 U/mg during the entire growth period (2 ? 24 weeks), whereas in case of shoot cultures, the specific activity escalated to 2.49 U/mg at 8 weeks, which then declined subsequently (1.95 U/mg). Similarly, callus cultures initially showed a higher phosphohydrolytic activity (3.41 U/mg protein) until 8 weeks by which period, it decreased with the passage of growth period. The present studies reveal an alternate system for resourcing of ACP from Atropa acuminata.Plant Tissue Cult. & Biotech. 26(1): 15-23, 2016 (June)


1994 ◽  
Vol 14 (3) ◽  
pp. 453-465 ◽  
Author(s):  
Marc Laruelle ◽  
Anissa Abi-Dargham ◽  
Mohammed S. AI-Tikriti ◽  
Ronald M. Baldwin ◽  
Yolanda Zea-Ponce ◽  
...  

In vivo benzodiazepine receptor equilibrium dissociation constant, KD, and maximum number of binding sites, Bmax, were measured by single photon emission computerized tomography (SPECT) in three baboons. Animals were injected with a bolus followed by a constant i.v. infusion of the high affinity benzodiazepine ligand [123I]iomazenil. Plasma steady-state concentration and receptor–ligand equilibrium were reached within 2 and 3 h, respectively, and were sustained for the duration (4–9 h) of the experiments (n = 15). At the end of the experiments, a receptor saturating dose of flumazenil (0.2 mg/kg) was injected to measure nondisplaceable activity. Experiments were carried out at various levels of specific activity, and Scatchard analysis was performed for derivation of the KD (0.59 ± 0.09 n M) and Bmax (from 126 n M in the occipital region to 68 n M in the striatum). Two animals were killed and [125I]iomazenil Bmax and KD were measured at 22 and 37°C on occipital homogenate membranes. In vitro values of Bmax (114 ± 33 n M) and 37°C KD (0.66 ± 0.16 n M) were in good agreement with in vivo values measured by SPECT. This study demonstrates that SPECT can be used to quantify central neuroreceptors density and affinity.


2020 ◽  
Author(s):  
Alexander Goikoetxea ◽  
Erin L Damsteegt ◽  
Erica V Todd ◽  
Andrew McNaughton ◽  
Neil J Gemmell ◽  
...  

AbstractMany teleost fishes undergo natural sex change, and elucidating the physiological and molecular controls of this process offers unique opportunities not only to develop methods of controlling sex in aquaculture settings, but to better understand vertebrate sexual development more broadly. Induction of sex change in some sequentially hermaphroditic or gonochoristic fish can be achieved in vivo through social manipulation, inhibition of aromatase activity, and steroid treatment. However, the induction of sex change in vitro has been largely unexplored. In this study, we established an in vitro culture system for ovarian explants in serum-free medium for a model sequential hermaphrodite, the New Zealand spotty wrasse (Notolabrus celidotus). This culture technique enabled evaluating the effect of various treatments with 17β-estradiol (E2), 11-ketotestosterone (11KT) or cortisol (CORT) on spotty wrasse ovarian architecture for 21 days. A quantitative approach to measuring the degree of ovarian atresia within histological images was also developed, using pixel-based machine learning software. Ovarian atresia likely due to culture was observed across all treatments including no-hormone controls, but was minimised with treatment of at least 10 ng/mL E2. Neither 11KT nor CORT administration induced proliferation of spermatogonia (i.e. sex change) in the cultured ovaries indicating culture beyond 21 days may be needed to induce sex change in vitro. The in vitro gonadal culture and analysis systems established here enable future studies investigating the paracrine role of sex steroids, glucocorticoids and a variety of other factors during gonadal sex change in fish.


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