scholarly journals Preserved visual memory and relational cognition performance in monkeys with selective hippocampal lesions

2020 ◽  
Vol 6 (29) ◽  
pp. eaaz0484 ◽  
Author(s):  
Benjamin M. Basile ◽  
Victoria L. Templer ◽  
Regina Paxton Gazes ◽  
Robert R. Hampton
Keyword(s):  
Nonhuman Primate ◽  
Source Memory ◽  
Rhesus Monkeys ◽  
Visual Memory ◽  
Temporal Order ◽  
Experimental Studies ◽  
Hippocampal Damage ◽  
Hippocampal Lesions ◽  
Hippocampus Proper ◽  
New Generation

The theory that the hippocampus is critical for visual memory and relational cognition has been challenged by discovery of more spared hippocampal tissue than previously reported in H.M., previously unreported extra-hippocampal damage in developmental amnesiacs, and findings that the hippocampus is unnecessary for object-in-context memory in monkeys. These challenges highlight the need for causal tests of hippocampal function in nonhuman primate models. Here, we tested rhesus monkeys on a battery of cognitive tasks including transitive inference, temporal order memory, shape recall, source memory, and image recognition. Contrary to predictions, we observed no robust impairments in memory or relational cognition either within- or between-groups following hippocampal damage. These results caution against over-generalizing from human correlational studies or rodent experimental studies, compel a new generation of nonhuman primate studies, and indicate that we should reassess the relative contributions of the hippocampus proper compared to other regions in visual memory and relational cognition.

Method and tools for determining heat transfer coefficients in organic liquids and solutions

2020 ◽  
pp. 45-55
Author(s):  
Aleksandr S. MYAKOCHIN ◽  
Petr V. NIKITIN ◽  
Sergey Yu. POBEREZHSKIY ◽  
Anna A. SHKURATENKO
Keyword(s):  
Heat Transfer ◽  
Experimental Studies ◽  
Pulse Method ◽  
Organic Liquids ◽  
Transfer Coefficients ◽  
Resistance Thermometer ◽  
Film Sensor ◽  
Heat Transfer Coefficients ◽  
Aerospace Technology ◽  
New Generation

The paper presents a method, tools and a newly developed algorithm for experimentally determining heat transfer coefficients in organic liquids and solutions. This work is made relevant by the problem of development of a new generation of aerospace technology. In this connection, improvements have been made to the pulse method of determining heat transfer coefficients that is based on the use of a micron-thick film sensor. The measurement setup was modified. A math model was constructed for the measuring sensor. Algorithms were developed for conducting the experiment and processing measurement results to determine heat transfer coefficients. Experimental uncertainties were analyzed. The paper provides results of experimental studies on certain organic liquids. The authors believe that the material presented in the paper will find application in research conducted at research institutions, engineering offices and universities, among researches, postgraduates and students. Key words: thermal and physical characteristics, organic liquids and their solutions, film-type electrical resistor, thin-film temperature sensor, voltage pulse, resistance thermometer, irregular heat transfer regime.

Experimental studies of the abuse potential of d,l-glaucine·1.5-phosphate in rhesus monkeys

1982 ◽  
Vol 16 (5) ◽  
pp. 851-854 ◽  
Author(s):  
C.R. Schuster ◽  
T. Aigner ◽  
C.E. Johanson ◽  
T.H. Gieske
Keyword(s):  
Rhesus Monkeys ◽  
Experimental Studies ◽  
Abuse Potential

Abstract 120: Surpass Flow Diverter for Endovascular Treatment of Intracranial Aneurysms - A Multicenter Preliminary Clinical and Angiographic Experience in 161 Patients with 186 Aneurysms

Stroke ◽  
2014 ◽  
Vol 45 (suppl_1) ◽  
Author(s):  
Ajay K Wakhloo ◽  
Pedro Lylyk ◽  
Joost de Vries ◽  
Matthew J Gounis ◽  
Alexandra Biondi ◽  
...  
Keyword(s):  
Intracranial Aneurysms ◽  
Experimental Studies ◽  
Flow Diverter ◽  
Posterior Circulation ◽  
Parent Artery ◽  
Anterior Circulation ◽  
Neck Size ◽  
Wide Range ◽  
New Generation

Objective: Validated through experimental studies a new generation of flow diverters (Surpass™ FD) was evaluated for treatment of intracranial aneurysms (IA). We present our multicenter preliminary clinical and angiographic experience. METHODS: To achieve the calculated flow disruption between the parent artery and aneurysm for thrombosis, single FDs were placed endovascularly in parent arteries. Implants measured 2.5-5.3mm in diameter with a length of 10-80mm. Patients were enrolled harboring a wide range large and giant wide-neck, fusiform and multiple small and blister-type aneurysm. Clinical and angiographic follow-up were performed at 1-3, 6, and 12 months. RESULTS: A total of 186 consecutive IA in 161 patients (mean age 57.1 years) were treated at 33 centers. Fifty-three aneurysms were smaller than 5 mm, 64 were 5-9.9mm in diameter, 47 were 10-20mm in diameter, and 22 were larger than 20mm (10.4±0.7mm, neck size 6.0±0.5mm [mean±SEM]) . The aneurysms originated in 63.4% from the internal carotid artery; 22% and 14.5% of the lesions were located in the anterior circulation distal to Circle of Willis and posterior circulation respectively. Technical success was achieved in 182 aneurysms (98%); average number of devices used per aneurysm was 1.05. Permanent morbidity and mortality during the follow-up period of mean 8.4months (range 1-24 months) including periprocedural complications for patients with aneurysms of the anterior circulation were encountered in 5 (3.7%) and 2 (1.5 %) patients respectively and 1 (3.7%) and 4 (14.8%) respectively for patients with aneurysms of the posterior circulation location. One-hundred-ten patients (70.5%) harboring 127 (70.2%) were available for clinical and angiographic follow-up and showed a complete or near complete aneurysm occlusion in 63 (81.8%) of the ICA. Aneurysms of the ICA≥10mm that were completely covered by FD and not previously stent-treated with a minimum of 6 months follow-up available in 16 patients showed a complete obliteration in 81.3% (n=13) and >90% occlusion in remaining 3 patients. CONCLUSION: Preliminary data demonstrate high safety and efficacy of a new generation of FD for a wide range of IA of the anterior and posterior circulation with a single implant.

New approaches to pharmacotherapy of allergic eye diseases

2015 ◽  
pp. 18-26
Author(s):  
Zoya Veselovska ◽  
Nataliia Veselovska
Keyword(s):  
Effective Means ◽  
Experimental Studies ◽  
Tear Film ◽  
Eye Diseases ◽  
Eye Drops ◽  
Lipid Layer ◽  
Ophthalmic Surgery ◽  
Promising Alternative ◽  
New Approaches ◽  
New Generation

The problem of studying the prеvalencе of allergic diseases of the eye and the search for new approaches and effective means to correct this condition does not lose its relevance. The presented data on the state of profound biochemical studies of the tear film in allergic conditions justify the expediency of the use of eye drops of a new generation. As a result of experimental studies on the effect on the lipid layer ectoine was discovered the mechanism of its therapeutic action. This paper presents compelling evidence that new eye drops based on natural molecules ectoine which are able to restore and maintain the functional state of the lipid layer of the tear film in the pharmacotherapy of аllergic diseases of anterior surface of the eye. The analyzes of multiple experimental data revealed the clear evidence of mechanisms of action on the eye and the first clinical experience with a new pharmacological agent testifies to its strong anti-inflammatory and regenerative effect due to the stabilization of the lipid layer of the tear film and the protection of the front surface of the eye tissue from the hyperosmolarity. It was confirmed by the subjective and objective reducing eye irritation and dryness in reducing itching and burning from the conjunctiva, to improve the moisture level of the surface of the eye, to reduce discomfort of the eyes. The drug can be used in children older than 2 years and adults, when wearing contact lenses, ophthalmic surgery and after an eye injury. Based on this, it can be conclude that the appearance in the arsenal of new-generation antiallergic eye drops (EYE-t) with sufficient efficacy and safety profile can be regarded as a promising alternative approach to the treatment of allergic and inflammatory eye diseases.

A Nonhuman Primate Model for Human Cerebral Malaria: Rhesus-Monkeys Experimentally Infected with Plasmodium fragile

1994 ◽  
Vol 78 (4) ◽  
pp. 371-376 ◽  
Author(s):  
H. Fujioka ◽  
P. Millet ◽  
Y. Maeno ◽  
S. Nakazawa ◽  
Y. Ito ◽  
...  
Keyword(s):  
Cerebral Malaria ◽  
Nonhuman Primate ◽  
Rhesus Monkeys ◽  
Nonhuman Primate Model ◽  
Primate Model

Effects of Large and Small Bilateral Hippocampal Lesions on Two Types of Passive-Avoidance Responses

1965 ◽  
Vol 16 (3_suppl) ◽  
pp. 1277-1290 ◽  
Author(s):  
Daniel R. Snyder ◽  
Robert L. Isaacson
Keyword(s):  
Passive Avoidance ◽  
Food Reward ◽  
Dorsal Hippocampus ◽  
Passive Avoidance Task ◽  
The Other ◽  
Hippocampal Damage ◽  
Avoidance Task ◽  
Small Compartment ◽  
Hippocampal Lesions ◽  
Avoidance Responses

Ten rats with large bilateral hippocampectomies, 10 rats with smaller amounts of damage of the dorsal hippocampus, 10 rats with destruction of postero-lateral neocortex, and 15 normal animals were trained in two types of passive-avoidance situations. One passive-avoidance task required inhibition of drinking while thirsty, the other required an animal to refrain from entering a small compartment after i: had been trained to enter, while hungry, for a food reward. Animals with the largest amounts of hippocampal destruction were impaired in both types of problems. Animals with smaller degrees of hippocampal damage were not different from normal animals in their ability to inhibit licking but were impaired in the other task. Animals with neocortical destruction showed impairment only in the licking situation.

Hippocampal lesions impair prolonged titrated avoidance by rhesus monkeys☆

1979 ◽  
Vol 63 (1) ◽  
pp. 28-34 ◽  
Author(s):  
William J. Jackson ◽  
Quentin R. Regestein
Keyword(s):  
Rhesus Monkeys ◽  
Hippocampal Lesions

Hippocampal Lesions in Rhesus Monkeys Disrupt Emotional Responses but Not Reinforcer Devaluation Effects

2008 ◽  
Vol 63 (11) ◽  
pp. 1084-1091 ◽  
Author(s):  
Yogita Chudasama ◽  
Katherine S. Wright ◽  
Elisabeth A. Murray
Keyword(s):  
Rhesus Monkeys ◽  
Emotional Responses ◽  
Hippocampal Lesions ◽  
Reinforcer Devaluation

scholarly journals Induction and Regulation of Crown Dentinogenesis: Embryonic Events as a Template for Dental Tissue Repair?

2001 ◽  
Vol 12 (5) ◽  
pp. 425-437 ◽  
Author(s):  
A.J. Smith ◽  
H. Lesot
Keyword(s):  
Growth Factors ◽  
Functional Activity ◽  
Tissue Repair ◽  
Experimental Studies ◽  
Secretory Activity ◽  
Dental Tissue ◽  
Odontoblast Differentiation ◽  
Cellular Processes ◽  
Dentin Matrix ◽  
New Generation

Close regulation of odontoblast differentiation and subsequent secretory activity is critical for dentinogenesis during both embryogenesis and tissue repair. Some dental papilla cells achieve commitment and specific competence, allowing them to respond to epithelially derived inductive signals during the process of odontoblast differentiation. Temporo-spatial regulation of odontoblast differentiation is dependent on matrix-mediated interactions involving the basement membrane (BM). Experimental studies have highlighted the possible roles of growth factors in these processes. Regulation of functional activity of odontoblasts allows for both ordered secretion of the primary dentin matrix and maintenance of vitality and down-regulation of secretory activity throughout secondary dentinogenesis. After injury to the mature tooth, the fate of the odontoblast can vary according to the intensity of the injury. Milder injury can result in up-regulation of functional activity leading to focal secretion of a reactionary dentin matrix, while greater injury can lead to odontoblast cell death. Induction of differentiation of a new generation of odontoblast-like cells can then lead to reparative dentinogenesis. Many similarities exist between development and repair, including matrix-mediation of the cellular processes and the apparent involvement of growth factors as signaling molecules despite the absence of epithelium during repair. While some of the molecular mediators appear to be common to these processes, the close regulation of primary dentinogenesis may be less ordered during tertiary dentinogenic responses.

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