The Effect of Chloroacetophenone on Chick Embryos Cultured in vitro

Development ◽  
1962 ◽  
Vol 10 (3) ◽  
pp. 373-382
Author(s):  
M. S. Lakshmi
Keyword(s):  
Xenopus Laevis ◽  
Average Length ◽  
Primitive Streak ◽  
Poultry Farm ◽  
Chick Embryos ◽  
Normal Process ◽  
Strong Emphasis ◽  
The Brain

Brachet's (1950) strong emphasis on the role of —SH-containing proteins in the process of induction has stimulated a study of the interference in the normal process of morphogenesis of chick embryos by chloroacetophenone, which has been described by Beatty (1951) as a specific and irreversible —SH inhibitor. He studied the effect of chloroacetophenone on the development of embryos of Rana and Triturus employing different concentrations. Deuchar (1957) also studied the action of the same chemical on the embryos of Xenopus laevis and has recorded abnormalities mainly in the brain and the eye. In the present work ω-chloroacetophenone (CAP) commercially known as phenacyl chloride (ω—C6H5.CO.CH2Cl) was employed. The sample used was a B.D.H. product. Fresh fertilized hens' eggs brought from a local poultry farm were incubated at 37·5° C. for 16 to 18 hours to obtain definitive primitive-streak stages (range of length from 1·75 mm. to 2 mm.) or for about 22 hours to obtain head-process stages (average length of the head process alone 0·56 mm.).

Notochord to endoderm signaling is required for pancreas development

Development ◽  
1997 ◽  
Vol 124 (21) ◽  
pp. 4243-4252 ◽  
Author(s):  
S.K. Kim ◽  
M. Hebrok ◽  
D.A. Melton
Keyword(s):  
Gene Expression ◽  
Developmental Stage ◽  
Pancreas Development ◽  
Chick Embryos ◽  
Carboxypeptidase A ◽  
Bud Development ◽  
Dorsal Pancreas ◽  
Stepwise Manner

The role of the notochord in inducing and patterning adjacent neural and mesodermal tissues is well established. We provide evidence that the notochord is also required for one of the earliest known steps in the development of the pancreas, an endodermally derived organ. At a developmental stage in chick embryos when the notochord touches the endoderm, removal of notochord eliminates subsequent expression of several markers of dorsal pancreas bud development, including insulin, glucagon and carboxypeptidase A. Pancreatic gene expression can be initiated and maintained in prepancreatic chick endoderm grown in vitro with notochord. Non-pancreatic endoderm, however, does not express pancreatic genes when recombined with the same notochord. The results suggest that the notochord provides a permissive signal to endoderm to specify pancreatic fate in a stepwise manner.

The use of siRNA as a pharmacological tool to assess a role for the transcription factor NF-IL6 in the brain under in vitro and in vivo conditions during LPS-induced inflammatory stimulation

2017 ◽  
Vol 28 (6) ◽  
Author(s):  
Jelena Damm ◽  
Joachim Roth ◽  
Rüdiger Gerstberger ◽  
Christoph Rummel
Keyword(s):  
Transcription Factor ◽  
Brain Cells ◽  
Nuclear Factor ◽  
Si Rna ◽  
The Brain ◽  
Deficient Mice ◽  
Transcription Factor Nuclear Factor

AbstractBackground:Studies with NF-IL6-deficient mice indicate that this transcription factor plays a dual role during systemic inflammation with pro- and anti-inflammatory capacities. Here, we aimed to characterize the role of NF-IL6 specifically within the brain.Methods:In this study, we tested the capacity of short interfering (si) RNA to silence the inflammatory transcription factor nuclear factor-interleukin 6 (NF-IL6) in brain cells underResults:In cells of a mixed neuronal and glial primary culture from the ratConclusions:This approach was, thus, not suitable to characterize the role NF-IL6 in the brain

scholarly journals The specification of noradrenergic locus coeruleus (LC) neurones depends on bone morphogenetic proteins (BMPs)

Development ◽  
2002 ◽  
Vol 129 (4) ◽  
pp. 983-991 ◽  
Author(s):  
Astrid Vogel-Höpker ◽  
Hermann Rohrer
Keyword(s):  
Transcription Factors ◽  
Locus Coeruleus ◽  
Bone Morphogenetic Proteins ◽  
Chick Embryos ◽  
Dorsal Midline ◽  
Neural Crest Development ◽  
Roof Plate ◽  
Rhombic Lip ◽  
The Brain

The role of BMPs in the development of the major noradrenergic centre of the brain, the locus coeruleus (LC), was investigated. LC generation is reflected by initial expression of the transcription factors Phox2a and Phox2b in dorsal rhombomere1 (r1), followed by expression of dopamine-β-hydroxylase and tyrosine hydroxylase. Bmp5 is expressed in the dorsal neuroepithelium in proximity to Phox2-expressing cells. BMP inhibition in stage 10 chick embryos resulted in the lack of LC neurones or in their generation at the dorsal midline, and loss of roof plate and rhombic lip, but it did not affect neural crest development. These results reveal late essential BMP functions in the specification of dorsal neuronal phenotypes in r1, including LC neurones, and in the development of dorsal midline structures.

The Effect of Chloroacetophenone on the Inducing Capacity of Hensen's Node

Development ◽  
1962 ◽  
Vol 10 (3) ◽  
pp. 383-388
Author(s):  
M. S. Lakshmi
Keyword(s):  
Organizer Region ◽  
High Capacity ◽  
Primitive Streak ◽  
Chick Embryos

In a previous paper (Lakshmi, 1962) the effects of ω-chloroacetophenone (CAP), which is an irreversible —SH inhibitor, on the morphogenesis of chick embryos cultured in vitro were reported. Brachet (1950) suggested that the —SH-containing proteins might be active in induction. Rapkine & Brachet (1951) studied the effect of monoiodoacetate on the amphibian organizer and observed that the organizer region retained a high capacity for induction despite treatment with the inhibitor. The action of monoiodoacetate is reversible, hence it was felt desirable to investigate the action of CAP on the living organiser of chick, namely Hensen's node. Chick embryos at the primitive-streak stage were explanted in vitro by New's (1955) technique. These were treated with 0·0005 M CAP for 15 and 30 minutes, 0·001 M CAP for 15 minutes, and 0·0015 M CAP for 15 minutes. 0·1 ml. of the solution was added to the endodermal surface of the explanted embryos.

scholarly journals Characterization of the Blood–Brain Barrier Integrity and the Brain Transport of SN-38 in an Orthotopic Xenograft Rat Model of Diffuse Intrinsic Pontine Glioma

Pharmaceutics ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 399 ◽  
Author(s):  
Catarina Chaves ◽  
Xavier Declèves ◽  
Meryam Taghi ◽  
Marie-Claude Menet ◽  
Joelle Lacombe ◽  
...  
Keyword(s):  
Blood Brain Barrier ◽  
Diffuse Intrinsic Pontine Glioma ◽  
Brain Barrier ◽  
Brain Delivery ◽  
Pontine Glioma ◽  
Anticancer Drug Delivery ◽  
Blood Brain ◽  
The Brain

The blood–brain barrier (BBB) hinders the brain delivery of many anticancer drugs. In pediatric patients, diffuse intrinsic pontine glioma (DIPG) represents the main cause of brain cancer mortality lacking effective drug therapy. Using sham and DIPG-bearing rats, we analyzed (1) the brain distribution of 3-kDa-Texas red-dextran (TRD) or [14C]-sucrose as measures of BBB integrity, and (2) the role of major ATP-binding cassette (ABC) transporters at the BBB on the efflux of the irinotecan metabolite [3H]-SN-38. The unaffected [14C]-sucrose or TRD distribution in the cerebrum, cerebellum, and brainstem regions in DIPG-bearing animals suggests an intact BBB. Targeted proteomics retrieved no change in P-glycoprotein (P-gp), BCRP, MRP1, and MRP4 levels in the analyzed regions of DIPG rats. In vitro, DIPG cells express BCRP but not P-gp, MRP1, or MRP4. Dual inhibition of P-gp/Bcrp, or Mrp showed a significant increase on SN-38 BBB transport: Cerebrum (8.3-fold and 3-fold, respectively), cerebellum (4.2-fold and 2.8-fold), and brainstem (2.6-fold and 2.2-fold). Elacridar increased [3H]-SN-38 brain delivery beyond a P-gp/Bcrp inhibitor effect alone, emphasizing the role of another unidentified transporter in BBB efflux of SN-38. These results confirm a well-preserved BBB in DIPG-bearing rats, along with functional ABC-transporter expression. The development of chemotherapeutic strategies to circumvent ABC-mediated BBB efflux are needed to improve anticancer drug delivery against DIPG.

scholarly journals DR5 Knockout Mice Are Compromised in Radiation-Induced Apoptosis

2005 ◽  
Vol 25 (5) ◽  
pp. 2000-2013 ◽  
Author(s):  
Niklas Finnberg ◽  
Joshua J. Gruber ◽  
Peiwen Fei ◽  
Dorothea Rudolph ◽  
Anka Bric ◽  
...  
Keyword(s):  
Cell Death ◽  
Null Mouse ◽  
Organ Specific ◽  
Radiation Induced ◽  
Induced Apoptosis ◽  
The Brain ◽  
Necrosis Factor

ABSTRACT DR5 (also called TRAIL receptor 2 and KILLER) is an apoptosis-inducing membrane receptor for tumor necrosis factor-related apoptosis-inducing ligand (also called TRAIL and Apo2 ligand). DR5 is a transcriptional target of p53, and its overexpression induces cell death in vitro. However, the in vivo biology of DR5 has remained largely unexplored. To better understand the role of DR5 in development and in adult tissues, we have created a knockout mouse lacking DR5. This mouse is viable and develops normally with the exception of having an enlarged thymus. We show that DR5 is not expressed in developing embryos but is present in the decidua and chorion early in development. DR5-null mouse embryo fibroblasts expressing E1A are resistant to treatment with TRAIL, suggesting that DR5 may be the primary proapoptotic receptor for TRAIL in the mouse. When exposed to ionizing radiation, DR5-null tissues exhibit reduced amounts of apoptosis compared to wild-type thymus, spleen, Peyer's patches, and the white matter of the brain. In the ileum, colon, and stomach, DR5 deficiency was associated with a subtle phenotype of radiation-induced cell death. These results indicate that DR5 has a limited role during embryogenesis and early stages of development but plays an organ-specific role in the response to DNA-damaging stimuli.

scholarly journals THE DEPENDENCE OF HEAD CURVATURE ON THE DEVELOPMENT OF THE HEART IN THE CHICK EMBRYO

1937 ◽  
Vol 14 (2) ◽  
pp. 229-231 ◽  
Author(s):  
C. H. WADDINGTON
Keyword(s):  
Chick Embryo ◽  
Blood Vessels ◽  
Brain Region ◽  
Normal Development ◽  
Anterior Part ◽  
Blood System ◽  
Chick Embryos ◽  
Aortic Arches ◽  
The Brain

1. The heart was removed from chick embryos of seven to twelve somites, and the embryos cultivated in vitro. The operation abolished the normal twisting of the anterior part of the embryo on to its left side and the general bending of the brain region into an arc. These two processes therefore seem to be dependent on the normal development of the heart. 2. The embryos showed a bending of the forebrain relative to the midbrain, which is therefore independent of the development of the heart. 3. The embryonic blood system, including the aortic arches, developed normally in many cases, but the blood vessels became enormously dilated. 4. The lateral evaginations of the foregut and the visceral arch mesenchyme underwent the first stages of differentiation in atypical positions, seemingly independently of each other or of any other structures.

scholarly journals The Two Faces of Ascorbate: Prooxidant Activity and Radio-Sensitisation

2021 ◽  
Author(s):  
◽  
Georgia Carson
Keyword(s):  
Dna Damage ◽  
Alternative Therapy ◽  
High Dose ◽  
Intravenous Injections ◽  
Unique Nature ◽  
Therapy Option ◽  
The Brain

<p>Although not recommended by mainstream oncologists, intravenous injections of pharmacological ascorbate are currently an alternative therapy option for cancer patients. Research has not yet determined whether high-dose ascorbate interacts favourably with radiation therapy to increase DNA damage, and therefore cell death in cancer. Some studies suggest that ascorbate can act as a prooxidant and increase the cytotoxic effect of irradiation in vitro. Glioblastoma multiforme (GBM) is a primary brain astrocytoma that is highly therapy resistant, so patients would be advantaged if ascorbate radiosensitised their cancer.  In this investigation, flow cytometry and single cell gel electrophoresis (comet tail assay) were used to measure three indicators of DNA damage in GBM cells in response to ascorbate and irradiation, and were contrasted with immunofluorescence-revealed DNA damage from an intracranial mouse model of GBM.   The pro-oxidant, radiosensitisation role of ascorbate was confirmed, as measured by H2AX, 8OHdG, and DSBs in vitro. With all three of these markers of DNA damage, combinations of irradiation and ascorbate had increased damage compared with individual treatments. However preliminary in vivo evidence indicates that increased DNA damage did not occur in an animal model of GBM, and in fact ascorbate may protect from DNA damage in an in vivo context.  These findings complement previous results from our lab, and serve to fill in gaps in knowledge specifically around the DNA damaging effects of ascorbate. The unique nature of the brain environment, as enclosed by the blood brain barrier, prevents translation of data from other non-brain cancer studies, as such, this investigation also contributes to the exploration of a much needed avenue of research. Considering the context of ascorbate treatment as a potentially harmful currently used adjuvant, it is imperative to confirm or disprove its efficacy in a clinically relevant environment.</p>

Studies on the Role of Fibrinolysis and Fibrinogen Degradation Products (FDP) in Analgesic Action of Morphine

1972 ◽  
Vol 28 (03) ◽  
pp. 359-366 ◽  
Author(s):  
Włodzimierz Buczko ◽  
Konstanty Wiśniewski
Keyword(s):  
Molecular Weight ◽  
Brain Tissue ◽  
Clinical Effect ◽  
Degradation Products ◽  
Analgesic Action ◽  
Fibrinogen Degradation Products ◽  
The Brain

SummaryThe role of fibrinolysis and FDP in the analgesic action of morphine in mice and rats was studied. It was shown that during activation of blood fibrinolysis, both the accumulation of morphine in the brain tissue of rats and the clinical effect of this drug were increased. Similar results were observed after morphine given simultaneously with FDP obtained in vitro. The data from the analysis of FDP carried out on Sephadex G-25 Fine columns suggest that only FDP of molecular weight of about 10,000 potentiate the action of morphine; smaller peptides decreased the action of this drug.

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