scholarly journals The forgotten contribution of J. E. Purkyně to dentistry

2020 ◽  
Vol 10 (2) ◽  
pp. 281-292
Author(s):  
Stefano Eramo ◽  
Giancarlo Barraco ◽  
Paolo Zampetti
Keyword(s):  
Optical Illusion ◽  
Politics And Literature ◽  
Enamel Formation ◽  
Short Article ◽  
Tooth Sensitivity ◽  
Histological Techniques ◽  
Dental Cement ◽  
Richard Owen ◽  
Dental Histology

Objectives: the name of Jan Evangelista Purkyně (Purkinje in German), born in Bohemia in 1787 and died in Prague in 1869, is mainly associated with discoveries in histology and specialist fields of Medicine like embriology, histological techniques, ophthalmology, cardiology and neurophysiology. This short article presents a brief account of his life, commemorates his achievements in biology and medicine but also in in the politics and literature of his Country (he was elected to the Diet of Bohemia but also he composed poems and important translations from German, French and Italian languages into Czech) and examines in depth his contribution to Dentistry. Materials and Methods: Purkyně’s major contributions to Dentistry, which focused on embryology and dental histology, endodontics and periodontology, are traced to two dissertations in Latin which were discussed by his pupils (Meyer Fraenkel and Isaac Raschkow), at Breslau University in 1835: we present a brief summary of each, with the major innovative findings highlighted. Results: the two dissertations contain remarkable, though often overlooked, contributions to Dentistry. Among these we can indicate the individuation of: the dental cement (substantia ostoidea), the acquired dental pellicle, the nature of optical illusion of Hunter-Schreger lines, the “enamel pulp” from which the enamel would evolve, the sub-odontoblastic nervous plexus which is the cause of tooth sensitivity, the predentine, the organic nature of the process of enamel formation, the dentine and enamel formation in opposing directions, the presence of alveolus membrane (id est: the periodontium). Conclusions: after reviewing the main innovations these two dissertations made to Dentistry, Purkyně’s personal share in both is very clear. Both the two his pupils acknowledged their debt to Purkyně and also famous contemporary Purkinje scientists such as Alexander Nasmyth, Sir Richard Owen, Sir James Paget had no doubt he is had generated the ideas expressed in the two little treatises.

The Life of Richard Owen

2009 ◽  
Author(s):  
Richard S. Owen
Keyword(s):  
Richard Owen

Fast and Reproducible Vascular Neointima Formation in the Hamster Carotid Artery: Effects of Trapidil and Captopril

1995 ◽  
Vol 74 (06) ◽  
pp. 1591-1596 ◽  
Author(s):  
H Matsuno ◽  
J M Stassen ◽  
M F Hoylaerts ◽  
J Vermylen ◽  
H Deckmyn
Keyword(s):  
Carotid Artery ◽  
Enzyme Inhibitor ◽  
Neointima Formation ◽  
Proliferating Cells ◽  
Dental Cement ◽  
Proliferation Indices ◽  
Experimental Drugs ◽  
The Media ◽  
Von Willebrand ◽  
Willebrand Factor

SummaryNeointima formation was induced in the hamster carotid artery by mechanical intraluminal injury with a catheter covered with roughened dental cement. Neointimal thickening occurred as early as 7 days after denudation and further increased during the next 1 to 2 weeks. Proliferation indices of smooth muscle cells (SMCs) showed the highest proportion of proliferating cells in the media and neointima respectively 1 and 5 days after the vascular injury. Transmission and scanning electron microscopy of damaged carotid artery sections as well as immuno-histochemical stainings of von Willebrand factor (vWF) confirmed that reendothelialization was progressive and already complete on day 14, at which time the neointima formation was almost complete.In order to pharmacologically characterize this model further, the effects on neointima formation of trapidil (triazolopyrimidine), a platelet-derived growth factor (PDGF) antagonist, and captopril, an angiotensin converting enzyme inhibitor, were investigated. Trapidil administered orally twice daily at total doses of 25, 50 and 100 mg/kg/day, started 3 days prior to infliction of injury and up to 7 or 14 days after the catheterization, significantly reduced neointima formation. Captopril administered orally three times daily at a total dose of 100 mg/kg/day, equally reduced neointima formation, with 100 mg/kg/day trapidil being more effective than 100 mg/kg/day captopril 7 days after injury. When the treatment by either one of these drugs was arrested on day 7, neointima formation resumed quickly.The hamster appears to be a small, reproducible and fast model for the study of SMC proliferation, requiring only relatively small amounts of experimental drugs. The model furthermore is sensitive to substances known to reduce neointima formation in other animal models.

Darwin's two competing phylogenetic trees: marsupials as ancestors or sister taxa?

2012 ◽  
Vol 39 (2) ◽  
pp. 217-233 ◽  
Author(s):  
J. David Archibald
Keyword(s):  
Fossil Record ◽  
Evolutionary Biology ◽  
Phylogenetic Trees ◽  
Charles Darwin ◽  
The Other ◽  
Charles Lyell ◽  
Single Origin ◽  
Molecular Studies ◽  
Richard Owen ◽  
First Time

Studies of the origin and diversification of major groups of plants and animals are contentious topics in current evolutionary biology. This includes the study of the timing and relationships of the two major clades of extant mammals – marsupials and placentals. Molecular studies concerned with marsupial and placental origin and diversification can be at odds with the fossil record. Such studies are, however, not a recent phenomenon. Over 150 years ago Charles Darwin weighed two alternative views on the origin of marsupials and placentals. Less than a year after the publication of On the origin of species, Darwin outlined these in a letter to Charles Lyell dated 23 September 1860. The letter concluded with two competing phylogenetic diagrams. One showed marsupials as ancestral to both living marsupials and placentals, whereas the other showed a non-marsupial, non-placental as being ancestral to both living marsupials and placentals. These two diagrams are published here for the first time. These are the only such competing phylogenetic diagrams that Darwin is known to have produced. In addition to examining the question of mammalian origins in this letter and in other manuscript notes discussed here, Darwin confronted the broader issue as to whether major groups of animals had a single origin (monophyly) or were the result of “continuous creation” as advocated for some groups by Richard Owen. Charles Lyell had held similar views to those of Owen, but it is clear from correspondence with Darwin that he was beginning to accept the idea of monophyly of major groups.

The publications and collections of Louis-Albert Necker (1786–1861)

2015 ◽  
Vol 42 (1) ◽  
pp. 66-75 ◽  
Author(s):  
John Hollier ◽  
Anita Hollier ◽  
Cédric Schnyder
Keyword(s):  
Necker Cube ◽  
Optical Illusion ◽  
Full List ◽  
Scientific Collections ◽  
Isle Of Skye

The Swiss geologist and mineralogist Louis-Albert Necker belonged to a family rich in scientific celebrities. Though a professor at the Académie de Genève for 25 years and author of numerous publications, he is mainly remembered today for his description of the “Necker cube” optical illusion and for leaving Geneva to spend the last 20 years of his life in Portree on the Isle of Skye. As a first step towards assessing Necker's contribution to science, a full list of his publications is presented, with comments about their citation in previous bibliographies and about published translations and abridgements. Information about the surviving specimens from his scientific collections, most of which are in the Muséum d'histoire naturelle de Genève, is also presented.

Signs and symptoms of craniomandibular dysfunction in a population of Spanish children

2018 ◽  
Vol 16 (1) ◽  
pp. 24
Author(s):  
Maria Esperanza Sánchez-Sánchez
Keyword(s):  
Signs And Symptoms ◽  
Permanent Teeth ◽  
Tooth Sensitivity ◽  
Craniomandibular Dysfunction ◽  
Teeth Grinding ◽  
Specific Questionnaire ◽  
Other Hand ◽  
Opening And Closing

The craniomandibular dysfunction (CMD) is a pathology that can appear at early ages. In a sample of 36 childrenresiding in Madrid (Spain), of both sexes, with ages between 7 and 13 years, the prevalence of signs and symptomsof CMD was analyzed. For that purpose, we did a dental and muscular examination, together with temporomandibularjoints, functional and occlusal examination, and completed with a specific questionnaire. The results revealedthat 100% showed some sign or sympthom of CMD. 77,8% of the pacients presented 3 or more CMD signs.The most prevalent were painful muscle palpation (94,4%), together with sliding anteriorly (91,7%), painful jointpalpation (69,4%), wear facets in permanent teeth (41,7%) and altered opening and closing trayectory (38,9%). Onthe other hand, only 38,9% showed any CMD symptom. The most prevalent symptoms were night teeth grinding(27,8%), followed by tooth sensitivity (19,4%) and fullness in the ears (16,7%). We conclude that in our sample,25% presented mild CMD (less that 3 signs or symptoms), 58,3% presented moderate CMD (from 3 to 6 signs orsymptoms) and 16,7% showed severe CMD (more than 6 symptoms). Nevertheless, it’s important to remark thatnone of these pacients came seeking treatment for his CMD and these symptoms were refered only when beingasked. Hence the importance of a comprehensive clinic history to precociously diagnose this pathology and havethe ability to prevent its progression.

A Survey Study on Attacks in MANET Ad-Hoc Network

2017 ◽  
Vol 7 (7) ◽  
pp. 387
Author(s):  
. Harpal ◽  
Gaurav Tejpal ◽  
Sonal Sharma
Keyword(s):  
Routing Protocol ◽  
Ad Hoc Network ◽  
Ad Hoc ◽  
Mobile Ad Hoc Network ◽  
Survey Study ◽  
Short Article ◽  
The People ◽  
Distance Vector ◽  
Mobile Ad Hoc ◽  
Real World Problems

In this time of instant units, Mobile Ad-hoc Network(MANET) has become an indivisible part for transmission for mobile devices. Therefore, curiosity about study of Mobile Ad-hoc Network has been growing because last several years. In this report we have mentioned some simple routing protocols in MANET like Destination Sequenced Distance Vector, Active Source Redirecting, Temporally-Ordered Redirecting Algorithm and Ad-hoc On Need Distance Vector. Protection is just a serious problem in MANETs because they are infrastructure-less and autonomous. Principal target of writing this report is to handle some simple problems and security considerations in MANET, operation of wormhole strike and acquiring the well-known routing protocol Ad-hoc On Need Distance Vector. This short article will be a great help for the people performing study on real world problems in MANET security.

Developing an Artificial Intelligence Project in your Radiology Department

2020 ◽  
Vol 2 ◽  
pp. 58-61 ◽  
Author(s):  
Syed Junaid ◽  
Asad Saeed ◽  
Zeili Yang ◽  
Thomas Micic ◽  
Rajesh Botchu
Keyword(s):  
Neural Network ◽  
Artificial Intelligence ◽  
Health Care ◽  
Deep Learning ◽  
Learning Algorithms ◽  
Radiology Department ◽  
Short Article ◽  
Computing Power ◽  
Road Map ◽  
Key Concepts

The advances in deep learning algorithms, exponential computing power, and availability of digital patient data like never before have led to the wave of interest and investment in artificial intelligence in health care. No radiology conference is complete without a substantial dedication to AI. Many radiology departments are keen to get involved but are unsure of where and how to begin. This short article provides a simple road map to aid departments to get involved with the technology, demystify key concepts, and pique an interest in the field. We have broken down the journey into seven steps; problem, team, data, kit, neural network, validation, and governance.

A supplementary note to 'An historical note on butterfly collecting in France during The Great War (1914–1918)'

2019 ◽  
Vol 70 (4) ◽  
pp. 245-248
Author(s):  
W. John Tennent ◽  
Stella Beavan ◽  
Huw Jones ◽  
Geoff Martin
Keyword(s):  
Great War ◽  
Historical Note ◽  
Supplementary Note ◽  
Short Article ◽  
The Great War ◽  
Battle Of The Somme ◽  
Entomological Data

Following a short article regarding the collection of a specimen of Iphiclides podalirius (Linnaeus, 1758) by A. A. Tullett, in France during the Battle of the Somme in 1916, further personal and entomological data regarding Tullett and others is presented.

Sign in / Sign up

Export Citation Format

Share Document