Establishing long-term colonies of marsupials to provide models for studying developmental mechanisms and their application to fertility control

2006 ◽  
Vol 54 (3) ◽  
pp. 197 ◽  
Author(s):  
Lynne Selwood ◽  
Shuliang Cui
Keyword(s):  
Fertility Control ◽  
Brushtail Possum ◽  
Pest Species ◽  
In Vitro Techniques ◽  
Induced Ovulation ◽  
Developmental Mechanisms ◽  
Successful Group ◽  
Conservation Of Endangered Species

To study marsupial developmental mechanisms and their application to fertility control, it is necessary to develop reliable procedures for breeding, colony maintenance, reproductive monitoring for obtaining known-age embryos and, if possible, an induced ovulation protocol. These procedures also provide means to enhance conservation of endangered species. Such procedures are examined in the stripe-faced dunnart, an excellent model for developmental analysis, and the common brush-tail possum, an agricultural and ecological pest species in New Zealand that has become a model for fertility control in marsupials. A long-term colony of the stripe-faced dunnart has been in existence for 21 years, and the procedures for its maintenance and continued survival are outlined, and include minimal reproductive contributions from wild-caught animals, and development of an appropriate timetable of development and induced-ovulation protocols. Common brushtail possum colonies are relatively frequent but have regular input from wild-caught animals. Procedures that minimise competition for prized resources and allow successful group housing of possums are outlined. For both species the available development timetables, in vitro techniques and induced ovulation protocols are essential tools for the study of developmental mechanisms and fertility control, respectively, and also have considerable implications for conservation of these and other species.

High levels of variability in immune response using antigens from two reproductive proteins in brushtail possums

2005 ◽  
Vol 32 (1) ◽  
pp. 1 ◽  
Author(s):  
Janine E. Deakin ◽  
Katherine Belov ◽  
Natalie C. Curach ◽  
Peter Green ◽  
Desmond W. Cooper
Keyword(s):  
Immune Response ◽  
New Zealand ◽  
Fertility Control ◽  
Tammar Wallaby ◽  
Brushtail Possum ◽  
Reproductive Proteins ◽  
Keyhole Limpet Haemocyanin ◽  
Carrier Molecule ◽  
High Level

Immune-based fertility control is being considered as an effective long-term approach for controlling the pest brushtail possum (Trichosurus vulpecula) population in New Zealand. This relies heavily on the immune response of each immunised possum. A strong and lasting immune response in the majority of individuals in a population is essential. In this study, possums and the model macropod species, the tammar wallaby (Macropus eugenii) were immunised with either a luteinising hormone or androgen receptor synthetic peptide coupled to the carrier molecule KLH (keyhole limpet haemocyanin). The antibody response of wallabies to the antigens was relatively uniform. In contrast, the possum immunoglobulin response to both synthetic peptides and KLH was variable. The apparent high level of variation in the immune response of possums raises questions about the feasibility of using these two antigens to control possum numbers in New Zealand.

scholarly journals Component Permeabilities and Water Contents in periplaneta Integument: Role Of The Epidermis Re-Examined

1985 ◽  
Vol 117 (1) ◽  
pp. 155-169 ◽  
Author(s):  
J. MACHIN ◽  
G. J. LAMPERT ◽  
M. J. O'DONNELL
Keyword(s):  
In Vitro Techniques ◽  
Linear Relationships ◽  
Before And After ◽  
Pressure Lowering ◽  
First Time ◽  
Water Contents

Improved in vivo and in vitro techniques for measuring cuticular water permeability are described. Air flowing over a cuticle disc mounted in a holder, permitted elimination of unstirred layers, or corrections for them, for the first time. Conditions inside the holder were incompatible with the long-term health of the epidermal cells. Significantly, mean permeabilities of these discs did not differ from values obtained in vivo on the same cuticular plate. Overall cuticular permeability was apportioned between endocuticle and combined epicuticle and exocuticle on the basis of measurements made before and after solvent extraction of lipids. Under identical activity gradients, endocuticle permeability was 35 to 40 times greater than the value for the other layer. Permeability of both component layers showed strongly non-linear relationships with ambient activity, with empirical proportionality to the reciprocal of vapour pressure lowering. Cuticle water contents measured in activity gradient conditions showed significantly higher values in vivo than in vitro. The amount of water contained in the combined epicuticle and exocuticle was too small to measure. We conclude that neither permeability nor water content data support the existence of a significant water barrier in the region of the epidermis.

Ultrastructural investigations of MDL 19,660-induced effects on the canine platelet and megakaryocyte

1990 ◽  
Vol 48 (3) ◽  
pp. 374-375
Author(s):  
D.E. Loudy ◽  
J. Sprinkle-Cavallo ◽  
J.T. Yarrington ◽  
F.Y. Thompson ◽  
J.P. Gibson
Keyword(s):  
Antidepressant Drug ◽  
Beagle Dogs ◽  
Long Term Effects ◽  
Short Term ◽  
Platelet Counts ◽  
Toxicological Studies ◽  
Induced Aggregation ◽  
Internal Architecture

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.

Human thymic epithelial cells maintain long-term survival of clonogenic myeloid and erythroid progenitor cells in vitro

2000 ◽  
Vol 111 (1) ◽  
pp. 363-370 ◽  
Author(s):  
Katsuto Takenaka ◽  
Mine Harada ◽  
Tomoaki Fujisaki ◽  
Koji Nagafuji ◽  
Shinichi Mizuno ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Progenitor Cells ◽  
Thymic Epithelial Cells ◽  
Erythroid Progenitor ◽  
Term Survival ◽  
Long Term Survival ◽  
Erythroid Progenitor Cells

Human liver cell cultivation for long-term in vitro toxicity studies in a miniaturized multi-compartment 3D bioreactor system

2011 ◽  
Vol 49 (01) ◽  
Author(s):  
SA Hoffmann ◽  
M Lübberstedt ◽  
U Müller-Vieira ◽  
D Knobeloch ◽  
A Nüssler ◽  
...  
Keyword(s):  
Liver Cell ◽  
Human Liver ◽  
In Vitro Toxicity ◽  
Cell Cultivation ◽  
Toxicity Studies ◽  
Human Liver Cell ◽  
Bioreactor System

Somatic Embryogenesis and In vitro Plant Regeneration in Vigna trilobata (L.) Verd. - A Potential Pasture Legume

1970 ◽  
Vol 19 (1) ◽  
pp. 89-99
Author(s):  
K. Choudhary ◽  
M. Singh ◽  
M. S. Rathore ◽  
N. S. Shekhawat
Keyword(s):  
Somatic Embryogenesis ◽  
Growth Regulators ◽  
Somatic Embryos ◽  
Basal Medium ◽  
Long Term Study ◽  
Continuous Application ◽  
First Time ◽  
Pasture Legume

This long term study demonstrates for the first time that it is possible to propagate embryogenic Vigna trilobata and to subsequently initiate the differentiation of embryos into complete plantlets. Initiation of callus was possible on 2,4-D. Somatic embryos differentiated on modified MS basal nutrient medium with 1.0 mg/l  of 2,4-D and 0.5 mg/l  of Kn. Sustained cell division resulted in globular and heart shape stages of somatic embryos. Transfer of embryos on to a fresh modified MS basal medium with 0.5 mg/l of Kn and 0.5 mg/l of GA3 helped them to attain maturation and germination. However, the propagation of cells, as well as the differentiation of embryos, were inhibited by a continuous application of these growth regulators. For this reason, a long period on medium lacking these growth regulators was necessary before the differentiation of embryos occurred again. The consequences for improving the propagation of embryogenic cultures in Vigna species are discussed. Key words: Pasture  legume, Vigna trilobata, Globular, Heart shape, somatic embryogenesis D.O.I. 10.3329/ptcb.v19i1.4990 Plant Tissue Cult. & Biotech. 19(1): 89-99, 2009 (June)

The depressing (negative) effect of oestradiol benzoate on the in vitro secretion of LH and FSH by the pituitary gland of the LRH-pretreated long-term ovariectomized rat changes into the augmentative (positive) effect after discontinuation of the LRH-pretreatment

1985 ◽  
Vol 110 (3) ◽  
pp. 329-337 ◽  
Author(s):  
G. A. Schuiling ◽  
H. Moes ◽  
T. R. Koiter
Keyword(s):  
Depressing Effect ◽  
Ovx Rats ◽  
Gonadotrophin Secretion ◽  
Oestradiol Benzoate ◽  
Negative Effect ◽  
Positive Effect ◽  
Perifusion System

Abstract. The effect of pretreatment in vivo with oestradiol benzoate on in vitro secretion of LH and FSH was studied in long-term ovariectomized (OVX) rats both at the end of a 5-day continuous in vivo pretreatment with LRH and 4-days after cessation of such LRH pretreatment. Rats were on day 0 sc implanted with osmotic minipumps which released LRH at the rate of 250 ng/h. Control rats were implanted with a piece of silicone elastomer with the dimensions of a minipump. On days 2 and 4 the rats were injected with either 3 μg EB or with oil. On day 5 part of the rats were decapitated and the in vitro autonomous (i.e. non-LRH-stimulated) and 'supra-maximally' LRHstimulated release of LH and FSH was studied using a perifusion system. From other rats the minipumps were removed on day 5 and perifusion was performed on day 9. On the 5th day of the in vivo LRH pretreatment the pituitary LH/FSH stores were partially depleted; the pituitaries of the EB-treated rats more so than those of the oil-injected rats. EB alone had no significant effect on the content of the pituitary LH- and FSH stores. On day 9, i.e. 4 days after removal of the minipumps, the pituitary LH and FSH contents had increased in both the oil- and the EB injected rats, but had not yet recovered to control values. In rats not subjected to the 5-days pretreatment with LRH EB had a positive effect on the supra-maximally LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. EB had no effect on the non-stimulated secretion of FSH. After 5 days of in vivo pretreatment with LRH only, the in vitro non-stimulated and supra-maximally LRH-stimulated secretion of both LH and FSH were strongly impaired, the effect correlating well with the LRH-induced depletion of the pituitary LH/FSH stores. In such LRH-pretreated rats EB had on day 5 a negative effect on the (already depressed) LRH-stimulated secretion of LH (not on that of FSH). EB had no effect on the non-stimulated LH/FSH secretion. It could be demonstrated that the negative effect of the combined LRH/EB pretreatment was mainly due to the depressing effect of this treatment on the pituitary LH and FSH stores: the effect of oestradiol on the pituitary LRH-responsiveness (release as related to pituitary gonadotrophin content) remained positive. In LRH-pretreated rats, however, this positive effect of EB was smaller than in rats not pretreated with LRH. Four days after removal of the minipumps there was again a positive effect of EB on the LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. The positive effect of EB on the pituitary LRH-responsiveness was as strong as in rats which had not been exposed to exogenous LRH. The non-stimulated secretion of FSH was again not affected by EB. The results demonstrate that the effect of EB on the oestrogen-sensitive components of gonadotrophin secretion consists of two components: an effect on the pituitary LRH-responsiveness proper, and an effect on the pituitary LH/FSH stores. The magnitude of the effect of EB on the LRH-responsiveness is LRH dependent: it is very weak (almost zero) in LRH-pretreated rats, but strong in rats not exposed to LRH as well as in rats of which the LRH-pretreatment was stopped 4 days previously. Similarly, the effect of EB on the pituitary LH and FSH stores is LRH-dependent: in the absence of LRH, EB has no influence on the contents of these stores, but EB can potentiate the depleting effect of LRH on the LH/FSH-stores. Also this effect disappear after cessation of the LRH-pretreatment.

Morphometrical estimation of fetal heart growth at different gestational ages by In vivo and In vitro techniques

2011 ◽  
Vol 3 (5) ◽  
pp. 491-494
Author(s):  
Dr. Haritha Kumari Nimmagadda ◽  
◽  
Pooja Pant Pooja Pant ◽  
Rajeev Mukhia ◽  
Dr. Aruna Mukherjee
Keyword(s):  
Fetal Heart ◽  
In Vitro Techniques

Role of 4-O Galloylchlorogenic Acid in Lung Cancer- An Insilico Approach

2017 ◽  
Vol 9 (5) ◽  
Author(s):  
Jaynthy C. ◽  
N. Premjanu ◽  
Abhinav Srivastava
Keyword(s):  
Lung Cancer ◽  
Cell Proliferation ◽  
In Silico ◽  
Computational Study ◽  
Regulation Mechanism ◽  
Down Regulation ◽  
Fruit Extract ◽  
In Vitro Techniques ◽  
Discovery Studio

Cancer is a major disease with millions of patients diagnosed each year with high mortality around the world. Various studies are still going on to study the further mechanisms and pathways of the cancer cell proliferation. Fucosylation is one of the most important oligosaccharide modifications involved in cancer and inflammation. In cancer development increased core fucosylation by FUT8 play an important role in cell proliferation. Down regulation of FUT8 expression may help cure lung cancer. Therefore the computational study based on the down regulation mechanism of FUT8 was mechanised. Sapota fruit extract, containing 4-Ogalloylchlorogenic acid was used as the inhibitor against FUT-8 as target and docking was performed using in-silico tool, Accelrys Discovery Studio. There were several conformations of the docked result, and conformation 1 showed 80% dock score between the ligand and the target. Further the amino acids of the inhibitor involved in docking were studied using another tool, Ligplot. Thus, in-silico analysis based on drug designing parameters shows that the fruit extract can be studied further using in-vitro techniques to know its pharmacokinetics.

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