scholarly journals Diverse Developmental Disorders from The One Ring: Distinct Molecular Pathways Underlie the Cohesinopathies

2012 ◽  
Vol 3 ◽  
Author(s):  
Julia A. Horsfield ◽  
Cristin G. Print ◽  
Maren Mönnich
2000 ◽  
Vol 1 (2) ◽  
pp. 165-176 ◽  
Author(s):  
Pamela Snow

AbstractThis paper deals with research which makes links between developmental problems such as language-learning disorders, attentional disorders, and behaviour disturbance on the one hand, and risk for misuse of alcohol and other drugs (AOD) in adolescence on the other. Poor academic performance is frequently cited as a risk for adolescent AOD misuse, however few workers have critically examined the role of linguistically-based academic sub-skills (e.g., oral and written language competence; strong social skills) which normally contribute to academic success, and hence operate as protective factors with respect to risk for AOD misuse. Studies which specifically address language skills and their association with risk for AOD misuse are reviewed, as are investigations which deal with patterns of comorbidity which are typically evident in clinical populations. Particular emphasis is placed on comorbidities between language-learning difficulties on the one hand, and behavioural or attentional disorders, on the other. It is argued that more explicitly investigating and intervening at the level of core language/social skill competencies might serve to strengthen protective factors in vulnerable groups. It is also noted that comorbid problems need to be considered as important covariates in studies of language disordered children and adolescents, rather than being treated as exclusionary criteria.


2021 ◽  
Vol 48 (3) ◽  
pp. 217-226
Author(s):  
Caroline Bartholmot ◽  
Sara Cabet ◽  
Mona Massoud ◽  
Jérôme Massardier ◽  
Axel Fichez ◽  
...  

<b><i>Objectives:</i></b> Our goal was to provide a better understanding of isolated short corpus callosum (SCC) regarding prenatal diagnosis and postnatal outcome. <b><i>Methods:</i></b> We retrospectively reviewed prenatal and postnatal imaging, clinical, and biological data from 42 cases with isolated SCC. <b><i>Results:</i></b> Prenatal imaging showed SCC in all cases (<i>n</i> = 42). SCC was limited to rostrum and/or genu and/or splenium in 21 cases, involved body in 16 cases, and was more extensive in 5 cases. Indirect imaging features included typical buffalo horn ventricles (<i>n</i> = 14), septal dysmorphism (<i>n</i> = 14), parallel lateral ventricles (<i>n</i> = 12), and ventriculomegaly (<i>n</i> = 4), as well as atypical features in 5 cases. SCC was associated with interhemispheric cysts and pericallosal lipomas in 3 and 6 cases, respectively. Aneuploidy was found in 2 cases. Normal psychomotor development, mild developmental disorders, and global developmental delay were found in 70, 15, and 15% of our cases, respectively. <b><i>Conclusions:</i></b> SCC should be investigated to look for pericallosal lipoma and typical versus atypical indirect features of corpus callosum agenesis (CCA). Prenatal counselling should be guided by imaging as well as clinical and genetic context. Outcome of patients with SCC was similar to the one presenting with complete CCA.


2019 ◽  
Author(s):  
Robin M Perelli ◽  
Matthew L O’Sullivan ◽  
Samantha Zarnick ◽  
Jeremy N Kay

AbstractAngiogenesis in the developing mammalian retina requires patterning cues from astrocytes. Developmental disorders of retinal vasculature, such as retinopathy of prematurity (ROP), involve arrest or mispatterning of angiogenesis. Whether these vascular pathologies involve astrocyte dysfunction remains untested. Here we demonstrate that the major risk factor for ROP – transient neonatal exposure to hyperoxia – disrupts formation of the angiogenic astrocyte template. Exposing mice to hyperoxia (75% O2) from postnatal day (P)0-4 suppressed astrocyte proliferation, while return to room air (21% O2) at P4 triggered extensive proliferation, massively increasing astrocyte numbers and disturbing their spatial patterning prior to arrival of developing vasculature. Proliferation required astrocytic HIF2α and was also stimulated by direct hypoxia (10% O2), suggesting that astrocyte oxygen sensing regulates the number of astrocytes produced during development. Along with astrocyte defects, return to room air also caused vascular defects reminiscent of ROP. Strikingly, these vascular phenotypes were more severe in animals that had larger numbers of excess astrocytes. Together, our findings suggest that fluctuations in environmental oxygen dysregulate molecular pathways controlling astrocyte proliferation, thereby generating excess astrocytes that interfere with retinal angiogenesis.


Development ◽  
2021 ◽  
Vol 148 (9) ◽  
Author(s):  
Robin M. Perelli ◽  
Matthew L. O'Sullivan ◽  
Samantha Zarnick ◽  
Jeremy N. Kay

ABSTRACT Angiogenesis in the developing mammalian retina requires patterning cues from astrocytes. Developmental disorders of retinal vasculature, such as retinopathy of prematurity (ROP), involve arrest or mispatterning of angiogenesis. Whether these vascular pathologies involve astrocyte dysfunction remains untested. Here, we demonstrate that the major risk factor for ROP – transient neonatal exposure to excess oxygen – disrupts formation of the angiogenic astrocyte template. Exposing newborn mice to elevated oxygen (75%) suppressed astrocyte proliferation, whereas return to room air (21% oxygen) at postnatal day 4 triggered extensive proliferation, massively increasing astrocyte numbers and disturbing their spatial patterning prior to the arrival of developing vasculature. Proliferation required astrocytic HIF2α and was also stimulated by direct hypoxia (10% oxygen), suggesting that astrocyte oxygen sensing regulates the number of astrocytes produced during development. Along with astrocyte defects, return to room air also caused vascular defects reminiscent of ROP. Strikingly, these vascular phenotypes were more severe in animals that had larger numbers of excess astrocytes. Together, our findings suggest that fluctuations in environmental oxygen dysregulate molecular pathways controlling astrocyte proliferation, thereby generating excess astrocytes that interfere with retinal angiogenesis.


2020 ◽  
Vol 44 (4) ◽  
pp. 169-173
Author(s):  
Jonathan Williams ◽  
Ruth Cain ◽  
Danilo Arnone ◽  
Michalis Kyratsous

Diagnostic categorisation is a typical stage of the medical model. Nevertheless, it is important to consider what is helpful to both the clinician and the patient when symptoms, experiences and perceptions are categorised. In this case report, we address the problem of comorbidity and complexity in psychiatry. Research and clinical experience point to significant overlap between personality disorders, mood disorders, and developmental disorders such as attention-deficit hyperactivity disorder. In the face of such complexity, we discuss ways of addressing and managing multiple diagnoses in clinical practice. We synthesise the perspectives and views of a general practice trainee, two consultant psychiatrists and a person with lived experience.


1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.


Author(s):  
P. R. Swann ◽  
W. R. Duff ◽  
R. M. Fisher

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.


Author(s):  
J.A. Eades ◽  
E. Grünbaum

In the last decade and a half, thin film research, particularly research into problems associated with epitaxy, has developed from a simple empirical process of determining the conditions for epitaxy into a complex analytical and experimental study of the nucleation and growth process on the one hand and a technology of very great importance on the other. During this period the thin films group of the University of Chile has studied the epitaxy of metals on metal and insulating substrates. The development of the group, one of the first research groups in physics to be established in the country, has parallelled the increasing complexity of the field.The elaborate techniques and equipment now needed for research into thin films may be illustrated by considering the plant and facilities of this group as characteristic of a good system for the controlled deposition and study of thin films.


Author(s):  
M. G. Lagally

It has been recognized since the earliest days of crystal growth that kinetic processes of all Kinds control the nature of the growth. As the technology of crystal growth has become ever more refined, with the advent of such atomistic processes as molecular beam epitaxy, chemical vapor deposition, sputter deposition, and plasma enhanced techniques for the creation of “crystals” as little as one or a few atomic layers thick, multilayer structures, and novel materials combinations, the need to understand the mechanisms controlling the growth process is becoming more critical. Unfortunately, available techniques have not lent themselves well to obtaining a truly microscopic picture of such processes. Because of its atomic resolution on the one hand, and the achievable wide field of view on the other (of the order of micrometers) scanning tunneling microscopy (STM) gives us this opportunity. In this talk, we briefly review the types of growth kinetics measurements that can be made using STM. The use of STM for studies of kinetics is one of the more recent applications of what is itself still a very young field.


Author(s):  
M. R. Pinnel ◽  
A. Lawley

Numerous phenomenological descriptions of the mechanical behavior of composite materials have been developed. There is now an urgent need to study and interpret deformation behavior, load transfer, and strain distribution, in terms of micromechanisms at the atomic level. One approach is to characterize dislocation substructure resulting from specific test conditions by the various techniques of transmission electron microscopy. The present paper describes a technique for the preparation of electron transparent composites of aluminum-stainless steel, such that examination of the matrix-fiber (wire), or interfacial region is possible. Dislocation substructures are currently under examination following tensile, compressive, and creep loading. The technique complements and extends the one other study in this area by Hancock.The composite examined was hot-pressed (argon atmosphere) 99.99% aluminum reinforced with 15% volume fraction stainless steel wire (0.006″ dia.).Foils were prepared so that the stainless steel wires run longitudinally in the plane of the specimen i.e. the electron beam is perpendicular to the axes of the wires. The initial step involves cutting slices ∼0.040″ in thickness on a diamond slitting wheel.


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