pH-dependence of the inducing activity of lithium ion

Development ◽  
1966 ◽  
Vol 15 (3) ◽  
pp. 371-386
Author(s):  
Yoshio Masui
Keyword(s):  
Neural Differentiation ◽  
Chemical Nature ◽  
Saline Solution ◽  
Ph Dependence ◽  
Neural Induction ◽  
Lithium Ion ◽  
The Other ◽  
Amphibian Embryos ◽  
Primary Induction ◽  
Endodermal Differentiation

Previous investigations of primary induction in amphibian embryos have shown that there are two kinds of heterogenic inductors, one of which induces the presumptive ectoderm towards neural differentiation alone, the other towards mesodermal or endodermal differentiation, and that they are characteristically distinct from one another in chemical nature (Yamada, 1961; Saxén & Toivonen, 1962). Various substances which are chemically dissimilar to each other have been found to be effective in neural induction, though their inducing activity was always thermostable. On the contrary, mesodermal and endodermal inductions were found to be caused only by certain proteins from vertebrate issues, and their inducing activity was always thermolabile. The neural induction of gastrula ectoderm can also be brought about by exposing the tissue to saline solution under appropriate conditions but in the absence of specific inductor, whereas this is not the case in the mesodermal and endodermal inductions (Barth, 1941; Holtfreter, 1944, 1945, 1947).

scholarly journals Predicting the new carbon nanocages, fullerynes: a DFT study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mohammad Qasemnazhand ◽  
Farhad Khoeini ◽  
Farah Marsusi
Keyword(s):  
Density Functional Theory ◽  
Lithium Ion Batteries ◽  
Density Functional ◽  
Lithium Ion ◽  
The Other ◽  
Electron Affinities ◽  
Chemical Formula ◽  
Functional Theory ◽  
Triple Bonds ◽  
Structural And Electronic Properties

AbstractIn this study, based on density functional theory, we propose a new branch of pseudo-fullerenes which contain triple bonds with sp hybridization. We call these new nanostructures fullerynes, according to IUPAC. We present four samples with the chemical formula of C4nHn, and the structures derived from fulleranes. We compare the structural and electronic properties of these structures with those of two common fullerenes and fulleranes systems. The calculated electron affinities of the sampled fullerynes are negative, and much smaller than those of fullerenes, so they should be chemically more stable than fullerenes. Although fulleranes also exhibit higher chemical stability than fullerynes, but pentagon or hexagon of the fullerane structures cannot pass ions and molecules. Applications of fullerynes can be included in the storage of ions and gases at the nanoscale. On the other hand, they can also be used as cathode/anode electrodes in lithium-ion batteries.

The influence of lithium on the competence of the ectoderm in Ambystoma mexicanum

Development ◽  
1964 ◽  
Vol 12 (2) ◽  
pp. 317-331
Author(s):  
D. O. E. Gebhardt ◽  
P. D. Nieuwkoop
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Ambystoma Mexicanum ◽  
The Other ◽  
Direct Influence ◽  
Amphibian Embryos ◽  
The Central Nervous System ◽  
The Subject ◽  
Morphogenetic Potential ◽  
Made In

The influence of lithium on the amphibian egg has been the subject of a number of investigations. From the work of Lehmann (1937), Töndury (1938), and Pasteels (1945) it is known that exposure of amphibian embryos to lithium results in a progressive cranio-caudal reduction of the central nervous system and a simultaneous conversion of the presumptive notochord into somites. Whereas these experiments were made with whole embryos, attempts have been made in recent years to localize the lithium effect by transplanting or explanting specific parts of the embryo. Gallera (1949), for instance, concluded from his experiments with transplants containing lithium treated presumptive chorda mesoderm, that lithium had reduced the ‘morphogenetic potential’ of this inductor. Lombard (1952), on the other hand, claimed that the susceptibility of amphibian eggs towards lithium was the result of the ion's direct influence on the ectoderm rather than on the presumptive archenteron roof.

scholarly journals Differentiation potential to neural-like cells in human adrenocortical carcinoma SW-13 cells

2019 ◽  
Author(s):  
Eriko Shimada ◽  
Yusuke Tsuruwaka
Keyword(s):  
Early Diagnosis ◽  
Adrenal Gland ◽  
Cancer Cells ◽  
Adrenocortical Carcinoma ◽  
Neural Differentiation ◽  
Neural Induction ◽  
Carcinoma Cells ◽  
Rare Cancer ◽  
Differentiation Potential ◽  
Aggressive Tumor

Various cancer cells are known to show neural differentiation. Adrenocortical carcinoma (ACC) is a rare and frequently aggressive tumor originating in the cortex of the adrenal gland. Early diagnosis of ACC is challenging due to a lot of unknown aspects such as cell characteristics in a rare cancer. In the present study, morphological features were examined in the adrenal cortex carcinoma cells SW-13 as an initial candidate, which were exposed to neural differentiation condition. SW-13 cells treated with the neural induction supplement showed neural-like differentiation with elongated filaments. It was suggested that SW-13 cells had neural differentiation potential and could be a research tool to elucidate the cell characteristics in future ACC studies.

The apoptotic effect of midazolam on the salivary gland of rats and the reversal effect by pilocarpine

2018 ◽  
Vol 96 (9) ◽  
pp. 898-901 ◽  
Author(s):  
Mariana Rinaldi ◽  
Aline Cristina Batista Rodrigues Johann ◽  
Patrícia Vida Cassi Bettega ◽  
Fábio Rocha ◽  
Sérgio Aparecido Ignácio ◽  
...  
Keyword(s):  
Salivary Gland ◽  
Wistar Rats ◽  
Saline Solution ◽  
Chronic Administration ◽  
Apoptotic Index ◽  
The Other ◽  
Parotid Glands ◽  
Control Groups ◽  
Reversal Effect ◽  
Apoptotic Effect

To evaluate the apoptosis in parotid glands of rats treated with midazolam associated or not with pilocarpine, 60 Wistar rats were assigned to 6 groups: control groups received saline solution for 30 days (S30) and 60 days (S60) and the other groups received pilocarpine for 60 days (P60), midazolam for 30 days (M30), midazolam for 30 days and 30 days of saline (M30 + S30), and finally midazolam for 30 days and 30 days of midazolam and pilocarpine (M30 + MP30). Histological sections were subjected to the TdT-mediated dUTP-biotin nick and labeling technique. The number of positive and negative cells was quantified, calculating the apoptotic index. ANOVA at 2 criteria and Tukey’s test were used. A greater apoptotic index was observed in the M30 (52.79 ± 9.01) and M30 + S30 (62.43 ± 8.52) groups when compared with the S30 (37.94 ± 5.94) and S60 (31.85 ± 9.18) groups, respectively (p < 0.05). There was no difference between M30 + MP30 (30.98 ± 6.19) and S60 (31.85 ± 9.18) groups regarding apoptotic index. Chronic administration of midazolam has been shown to increase the number of apoptotic cells in the parotid glands of rats. However, pilocarpine inhibited this effect, thus inhibiting the apoptosis.

Spatial aspects of neural induction in Xenopus laevis

Development ◽  
1989 ◽  
Vol 107 (4) ◽  
pp. 785-791 ◽  
Author(s):  
E.A. Jones ◽  
H.R. Woodland
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Peripheral Nerves ◽  
Neural Differentiation ◽  
Neural Induction ◽  
Neural Tissue ◽  
Thoracic Region ◽  
Lateral Extent ◽  
Tail Tip ◽  
Developing Nervous System

A monoclonal antibody, 2G9, has been identified and characterised as a marker of neural differentiation in Xenopus. The epitope is present throughout the adult central nervous system and in peripheral nerves. Staining is first detected in embryos at stage 21 in the thoracic region. By stage 29 it stains the whole central nervous system, except the tail tip. The epitope is present in a 65K Mr protein, and includes sialic acid. The antibody also reacts with neural tissue in mice and axolotls and newts. 2G9 was used to show that both notochord and somites are capable of neural induction, and the stimulus is present as late as stage 22. Attempts to demonstrate the induction of nervous system by developing nervous system (homoiogenetic induction) were unsuccessful. The view that the lateral extent of the nervous system might be determined by that of the inductive stimulus is discussed. Neural induction was detected as early as stage 10 and occurs in embryos without gastrulation and without cell division from stage 7 1/2.

scholarly journals Use of Platelet-Rich Fibrin Associated with Xenograft in Critical Bone Defects: Histomorphometric Study in Rabbits

Symmetry ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1293
Author(s):  
Paulo Wilson Maia ◽  
Marcelo Lucchesi Teixeira ◽  
Luís Guilherme Scavone de Macedo ◽  
Antonio Carlos Aloise ◽  
Celio Amaral Passos Junior ◽  
...  
Keyword(s):  
Bone Formation ◽  
Saline Solution ◽  
Healing Process ◽  
Test Group ◽  
The Other ◽  
Control Group ◽  
Collagen Membrane ◽  
Platelet Rich Fibrin ◽  
Histomorphometric Study ◽  
Significant Difference

Platelet-rich fibrin (PRF) is an autologous material used to improve bone regeneration when associated with bone grafts. It affects tissue angiogenesis, increasing the healing process and, theoretically, presenting potential to increase bone neoformation. The aim of this study was to verify, histomorphometrically, the effects of the association of PRF to a xenograft. Twelve adult white New Zealand rabbits were randomly assigned into two groups containing six animals each. After general anesthesia of the animals, two critical defects of 12 mm were created in the rabbit calvaria, one on each side of the sagittal line. Each defect was filled with the following biomaterials: in the control group (CG), xenograft hydrated with saline solution filling one defect and xenograft hydrated with saline solution covered with collagen membrane on the other side; in the test group (TG), xenograft associated with PRF filling the defect of one side and xenograft associated with PRF covered with collagen membrane on the other side. After eight weeks the animals were euthanized and a histomorphometric analysis was performed. The results showed that in the sites that were covered with collagen membrane, there was no statistically significant difference for all the analyzed parameters. However, when comparing the groups without membrane coverage, a statistically significant difference could be observed for the vital mineralized tissue (VMT) and nonmineralized tissue (NMT) parameters, with more VMT in the test group and more NMT in the control group. Regarding the intragroup comparison, the use of the membrane coverage presented significant outcomes in both groups. Therefore, in this experimental model, PRF did not affect the levels of bone formation when a membrane coverage technique was used. However, higher levels of bone formation were observed in the test group when membrane coverage was not used.

scholarly journals PSX-7 Induction of sexual behavior of Dorper rams treated with GnRH in northern Mexico

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 462-462
Author(s):  
Francisco G Véliz-Deras ◽  
Cesar Meza-Herrera ◽  
Oscar Angel ◽  
Leticia R Gaytan-Alemán ◽  
Angeles De Santiago-Miramontes ◽  
...  
Keyword(s):  
Body Weight ◽  
Sexual Behavior ◽  
Sexual Behaviors ◽  
Saline Solution ◽  
Physiological Saline ◽  
The Other ◽  
Sheep Industry ◽  
Northern Mexico ◽  
Physiological Saline Solution ◽  
Behavior Test

Abstract We evaluated whether the GnRH application induces the sexual behavior of Dorper rams in northern Mexico (26º N). Rams (n = 12) were divided into 2 homogenous groups (n = 6 each) in body weight (80.0 ± 2.8 kg) and a body condition of (3.3 ± 0.2 units, scale of 1–5). One group (GnRH) received 100 Μ g of GnRH i.m., every 3 d x 1 week, while the other (CONT) received 0.5 ml of physiological saline solution every 3 d x 1 week. At the end of the treatments, rams were subjected to a sexual behavior test by exposing each male to one estrus female during both appetitive (ASB, anogenital sniffing, approaching, kicking, vocalizations) and consummatory (CSB: unsheathing, mount attempt, full mount, mount with unsheathing and mount with ejaculation) sexual behaviors where registered. The CSA and CSC behavior frequencies were compared by a χ 2 test (SYSTAT 12). Both ASB and CSB behaviors favored (P &lt; 0.05) to the GnRH rams; ASB 77% vs 23% and CSB 76% vs 23%. A demonstration of GnRH in Dorper rams in northern Mexico (26 ° N) induced sexual behavior; this should be of interest to enhance the out-of-season reproductive outcomes in the sheep industry.

scholarly journals The Capacity of Periodontal Gel to Occupy the Spaces Inside the Periodontal Pockets Using Computational Fluid Dynamic

2019 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
Luca Levrini ◽  
Luigi Paracchini ◽  
Maria Giulia Nosotti
Keyword(s):  
Rheological Properties ◽  
Computational Fluid Dynamic ◽  
Type I Collagen ◽  
Saline Solution ◽  
Fluid Dynamic ◽  
The Other ◽  
Periodontal Pocket ◽  
Type I ◽  
Cat Scan ◽  
Different Types

The aim of the current work is to demonstrate the capacity of a new periodontal gel to occupy the spaces inside the periodontal pockets through Computational Fluid Dynamic (CFD). The test gel consists of two resorbable medical grade polymers (PEO, Poly Ethylen Oxide and HPMC, Hydroxy Propyl Metyl Cellulose), Type I Collagen, SAP (Vitamin C), and PBS (Saline Solution), while the control gel is 14% doxyclin controlled release gel, which is used for treating periodontal pockets with probing ≥5 mm after scaling and root plaining. The study examined the fluid dynamic analysis (Computational Fluid Dynamic—CFD) of two different gels, used in dentistry to treat periodontitis, in relation to both the geometry of the periodontal pocket and the function of two different types of needles that are used to distribute the preparation. The periodontal pocket was determined by reading DICOM images taken from the patient’s CAT scan. The results show that the H42® gel comes out uniformly compared to the other gel. Moreover, it is possible to observe how the rheological properties of the gel allow the fluid to spread evenly within the periodontal pocket in relation to the geometry of the needle. In particular, H42® gel exits in a constant way both from the first and the second exit. In fact, it was observed that by changing the geometry of the needle or the type of periodontal gel, the distribution of the gel inside the pocket was no longer homogeneous. Thus, having the correct rheological properties and correct needle geometries both speeds up the gel and optimizes the pressure distribution. Currently, the literature is still lacking, therefore further studies will be needed to confirm these results.

The Bβ-sheet in the PAI-1 Molecule Plays an Important Role for Its Stability

2000 ◽  
Vol 83 (06) ◽  
pp. 896-901 ◽  
Author(s):  
Guang-Chao Sui ◽  
Björn Wiman
Keyword(s):  
Amino Acids ◽  
Half Life ◽  
Ph Dependence ◽  
The Other ◽  
Wild Type ◽  
E Coli ◽  
Reactive Center ◽  
The Stability ◽  
Β Sheet ◽  
Pai 1

SummaryWe have investigated the B β-sheet in PAI-1 regarding its role for the stability of the molecule. The residues from His219 to Tyr241 (except for Gly230 and Pro240), covering the s2B and s3B strands, and in addition His185 and His190 were substituted by amino acids with opposite properties. The 23 generated single-site changed mutants and also wild type PAI-1 (wtPAI-1) were expressed in E. coli. Subsequently they were purified by heparin-Sepharose and anhydrotrypsin agarose affinity chromatographies. The stability of the purified PAI-1 variants was analyzed at 37° C and at different pHs (5.5, 6.5 or 7.5). At pH 7.5 and 37° C, single substitutions of the residues in the central portions of both strands 2 and 3 in the B β-sheet (Ile223 to Leu226 on s2B and Met235 to Ile237 on s3B), caused a significant decrease in stability, yielding half-lives of about 10–25% as compared to wtPAI-1. On the other hand, mutations at both sides of the central portion of the B β-sheet (Tyr221, Asp222, Tyr228 and Thr232) frequently resulted in an increased PAI-1 stability (up to 7-fold). While wtPAI-1 exhibited prolonged half-lives at pH 6.5 and 5.5, the PAI-1 variant Y228S was more stable at neutral pH (half-life of 9.6 h at pH 7.5) as compared to its half-life at pH 5.5 (1.1 h). One of the 4 modified histidine residues (His229) resulted in a variant with a clearly affected stability as a function of pH, suggesting that it may, at least in part, be of importance for the pH dependence of the PAI-1 stability. Thus, our data demonstrate that the B β-sheet is of great importance for the stability of the molecule. Modifications in this part causes decreased or increased stability in a certain pattern, suggesting effects on the insertion rate of the reactive center loop into the A β-sheet of the molecule.

scholarly journals BRIEF REPORT: Appearance of Platelet-Clumping Substance in Plasma of Rabbits after Intravenous Injection of Agar-Solution, Bacterial Endotoxin or Adrenaline

Blood ◽  
1967 ◽  
Vol 30 (6) ◽  
pp. 792-795 ◽  
Author(s):  
HIROH YAMAZAKI ◽  
TATSUO SHIMAMOTO ◽  
HIROSHI MURASE ◽  
TAKIO SHIMAMOTO
Keyword(s):  
Escherichia Coli ◽  
Intravenous Injection ◽  
Saline Solution ◽  
Platelet Rich Plasma ◽  
The Other ◽  
Bacterial Endotoxin ◽  
Magnesium Ions ◽  
Normal Platelet ◽  
Rabbit Platelets ◽  
Edta Plasma

Abstract The platelet-clumping substance appeared statistically significant (p < 0.01 ∼ 0.05) in the heparinized plasma of 29 rabbits collected 5 minutes, 30 minutes, and 1 and 2 hours after the intravenous injection of either 5 ml./Kg. of 0.5 per cent agar-saline solution, 100 µg./Kg. of bacterial endotoxin derived from Escherichia coli, or 10 µg./Kg. of adrenaline, as compared with that in the platelet-saline suspension from the other 36 rabbits. At the same time, the circulating platelet count decreased significantly (p<0.01 ∼0.05). Twenty-four hours after the injection these changes disappeared. The platelet-clumping substance was detected only in heparinized plasma, and not in citrated, oxalated, and EDTA-plasma or serum. The addition or removal of calcium or magnesium ions did not affect the appearance of clumping of platelets. It is stable for storage at 4 C. and is not dialyzable. It induced clumping of platelets not only in the platelet-saline suspension, but also in the platelet-rich plasma, while ADP, serotonin, catecholamine or thrombin (0.001 ∼ 100µg./ml. or units/ml.) did not induce clumping of washed rabbit platelets even under the presence of the normal platelet-free heparinized plasma.

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