Functional Development of Retinotopic Maps

2009 ◽  
Vol 65 ◽  
pp. S10
Author(s):  
Jianhua Cang
2019 ◽  
Vol 15 (2) ◽  
pp. 154-165
Author(s):  
Oscar G. Gómez-Duarte ◽  
Pearay L. Ogra

The mucosal surfaces and the skin are the primary sites of interactions between the mammalian host and the external environment. These sites are exposed continuously to the diverse components of the environment, including subcellular, unicellular and multicellular organisms, dietary agents and food products; and numerous other soluble or cellular air or water borne products. The development of innate and adaptive immunity in the mucosal surfaces and the skin are the principal mechanism of mammalian defense evolved to date, in order to maintain effective homeostatic balance between the host and the external environment. The innate immune functions are mediated by a number of host specific Pathogen Recognition Receptors (PRR), designed to recognize unique Pathogen Associated Molecular Patterns (PAMP), essential to the molecular structure of the microorganism. The major components of specific adaptive immunity in the mucosal surfaces include the organized antigen-reactive lymphoid follicles in different inductive mucosal sites and the effector sites of the lamina propria and sub-epithelial regions, which contain lymphoid and plasma cells, derived by the homing of antigen sensitized cells from the inductive sites. The acquisition of environmental microbiome by the neonate in its mucosal surfaces and the skin, which begins before or immediately after birth, has been shown to play a critical and complex role in the development of mucosal immunity. This report provides an overview of the mammalian microbiome and highlights its role in the evolution and functional development of immunologic defenses in the mucosal surface under normal physiologic conditions and during infectious and non-infectious inflammatory pathologic states associated with altered microbiota.


2006 ◽  
Vol 274 (1611) ◽  
pp. 827-832 ◽  
Author(s):  
Colin R Tosh ◽  
Andrew L Jackson ◽  
Graeme D Ruxton

Individuals of many quite distantly related animal species find each other attractive and stay together for long periods in groups. We present a mechanism for mixed-species grouping in which individuals from different-looking prey species come together because the appearance of the mixed-species group is visually confusing to shared predators. Using an artificial neural network model of retinotopic mapping in predators, we train networks on random projections of single- and mixed-species prey groups and then test the ability of networks to reconstruct individual prey items from mixed-species groups in a retinotopic map. Over the majority of parameter space, cryptic prey items benefit from association with conspicuous prey because this particular visual combination worsens predator targeting of cryptic individuals. However, this benefit is not mutual as conspicuous prey tends to be targeted most poorly when in same-species groups. Many real mixed-species groups show the asymmetry in willingness to initiate and maintain the relationship predicted by our study. The agreement of model predictions with published empirical work, the efficacy of our modelling approach in previous studies, and the taxonomic ubiquity of retinotopic maps indicate that we may have uncovered an important, generic selective agent in the evolution of mixed-species grouping.


PLoS ONE ◽  
2012 ◽  
Vol 7 (5) ◽  
pp. e36859 ◽  
Author(s):  
Linda Henriksson ◽  
Juha Karvonen ◽  
Niina Salminen-Vaparanta ◽  
Henry Railo ◽  
Simo Vanni

1969 ◽  
Vol 129 (6) ◽  
pp. 1235-1246 ◽  
Author(s):  
Esther F. Hays

Work has been presented which suggests that thymus epithelial reticular cells are not effective in restoring the microscopic morphology of lymphoid tissues and their immunologic capacities. They function in recruiting precursors of thymus lymphocytes from the host animals to produce an organ which, after it becomes architecturally normal, can reconstitute the defective host. Intact thymus grafts in situ from 10–14 days, but not for shorter periods of time, have been shown to result in a return toward normal of these two parameters. Evidence is offered to show that few dividing cellular components in the lymphoid tissue originate from the thymus remnant grafts, and that a minor cellular component is contributed by the intact grafts. These data support the concept that the structural and functional development of the lymphatic tissue in thymectomized animals is dependent on thymus lymphoid cells and/or their products, and that the epithelial-reticular cells do not have a direct action in peripheral lymphoid reconstitution.


Peptides ◽  
1980 ◽  
Vol 1 ◽  
pp. 125-134 ◽  
Author(s):  
Don Gash ◽  
Celia D. Sladek ◽  
John R. Sladek

Author(s):  
G. Piccione ◽  
S. Casella ◽  
P. Pennisi ◽  
C. Giannetto ◽  
A. Costa ◽  
...  

Rectal temperature, heart and respiratory rates, and the course of some blood parameters were monitored in calves during perinatal and neonatal periods. The study was carried out on eight Limousine calves. From all subjects, rectal temperature, heart rate, and respiratory rate were measured. Blood samples were taken at the same hour (9am) from the external jugular vein, and then centrifuged and stored until analyses. By means of an UV spectrophotometer, the following blood parameters were assessed for each subject: total protein, total cholesterol, triglycerides, glucose, non-esterified fatty acids (NEFA), urea, creatinine, cholinesterase, lactate dehydrogenase (LDH), hydroxybutirate, glutamate pyruvate transaminases (GPT), glutamate oxalacetate transaminases (GOT), direct and total bilirubin, magnesium, iron, potassium, phosphorus, chloride and sodium. The results showed a significant effect of days of life (P<0.05) only on total cholesterol, creatinine and GOT during the first week of life and a significant effect of days of life on rectal temperature, heart rate, respiratory rate, total cholesterol, NEFA, creatinina, and GOT during the first month of life. A correlation among individual values for postnatal age (days of life) and heart rate in calves during the first month of life was observed. In conclusion, modifications of studied parameters could be attributed to functional development of calves in neonatal period and contribute to the knowledge of adaptation processes in calf during the first week and the first month of life resulting useful for the diagnosis and treatment of any neonatal diseases.


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