scholarly journals Cerebellar Astrocytes: Much More Than Passive Bystanders In Ataxia Pathophysiology

2020 ◽  
Vol 9 (3) ◽  
pp. 757 ◽  
Author(s):  
Valentina Cerrato

Ataxia is a neurodegenerative syndrome, which can emerge as a major element of a disease or represent a symptom of more complex multisystemic disorders. It comprises several forms with a highly variegated etiology, mainly united by motor, balance, and speech impairments and, at the tissue level, by cerebellar atrophy and Purkinje cells degeneration. For this reason, the contribution of astrocytes to this disease has been largely overlooked in the past. Nevertheless, in the last few decades, growing evidences are pointing to cerebellar astrocytes as crucial players not only in the progression but also in the onset of distinct forms of ataxia. Although the current knowledge on this topic is very fragmentary and ataxia type-specific, the present review will attempt to provide a comprehensive view of astrocytes’ involvement across the distinct forms of this pathology. Here, it will be highlighted how, through consecutive stage-specific mechanisms, astrocytes can lead to non-cell autonomous neurodegeneration and, consequently, to the behavioral impairments typical of this disease. In light of that, treating astrocytes to heal neurons will be discussed as a potential complementary therapeutic approach for ataxic patients, a crucial point provided the absence of conclusive treatments for this disease.

Micromachines ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 287
Author(s):  
Ye Lin Park ◽  
Kiwon Park ◽  
Jae Min Cha

Over the past decades, a number of bone tissue engineering (BTE) approaches have been developed to address substantial challenges in the management of critical size bone defects. Although the majority of BTE strategies developed in the laboratory have been limited due to lack of clinical relevance in translation, primary prerequisites for the construction of vascularized functional bone grafts have gained confidence owing to the accumulated knowledge of the osteogenic, osteoinductive, and osteoconductive properties of mesenchymal stem cells and bone-relevant biomaterials that reflect bone-healing mechanisms. In this review, we summarize the current knowledge of bone-healing mechanisms focusing on the details that should be embodied in the development of vascularized BTE, and discuss promising strategies based on 3D-bioprinting technologies that efficiently coalesce the abovementioned main features in bone-healing systems, which comprehensively interact during the bone regeneration processes.


2021 ◽  
Vol 10 (11) ◽  
pp. 2457
Author(s):  
Birgit J. Gerecke ◽  
Rolf Engberding

Noncompaction cardiomyopathy (NCCM) has gained increasing attention over the past twenty years, but in daily clinical practice NCCM is still rarely considered. So far, there are no generally accepted diagnostic criteria and some groups even refuse to acknowledge it as a distinct cardiomyopathy, and grade it as a variant of dilated cardiomyopathy or a morphological trait of different conditions. A wide range of morphological variants have been observed even in healthy persons, suggesting that pathologic remodeling and physiologic adaptation have to be differentiated in cases where this spongy myocardial pattern is encountered. Recent studies have uncovered numerous new pathogenetic and pathophysiologic aspects of this elusive cardiomyopathy, but a current summary and evaluation of clinical patient management are still lacking, especially to avoid mis- and overdiagnosis. Addressing this issue, this article provides an up to date overview of the current knowledge in classification, pathogenesis, pathophysiology, epidemiology, clinical manifestations and diagnostic evaluation, including genetic testing, treatment and prognosis of NCCM.


2020 ◽  
Vol 12 (5) ◽  
pp. 1947 ◽  
Author(s):  
Philip Hallinger ◽  
Vien-Thong Nguyen

This systematic review of research used science mapping as a means of analyzing the knowledge base on education for sustainable development (ESD) in K-12 schooling. The review documented the size, growth trajectory and geographic distribution of this literature, identified high impact scholars and documents, and visualized the “intellectual structure” of the field. The database examined in this review consisted of 1842 English language, Scopus-indexed documents published between 1990 and 2018. The review found that the knowledge base on ESD has grown dramatically over the past 30 years, with a rapidly accelerating rate of publication in the past decade. Although the field has been dominated by scholarship from Anglo-American_European nations, there is evidence of increasing geographic diversification of the ESD knowledge base over the past 15 years. Citation analyses identified authors who have had a significant influence on the development of this literature. Author co-citation analysis revealed three “schools of thought” that comprise the “intellectual structure” of this knowledge base: Education for Sustainable Development, Developing a Sustainability Mindset, Teaching and Learning for Sustainability. Document content analyses led to the conclusion that the current knowledge base is heavily weighted towards critical, descriptive and prescriptive papers, with an insufficient body of analytical empirical studies. Several recommendations are offered for strengthening this literature.


2002 ◽  
Vol 15 (1) ◽  
pp. 125-144 ◽  
Author(s):  
Cees M. Verduin ◽  
Cees Hol ◽  
André Fleer ◽  
Hans van Dijk ◽  
Alex van Belkum

SUMMARY Moraxella catarrhalis (formerly known as Branhamella catarrhalis) has emerged as a significant bacterial pathogen of humans over the past two decades. During this period, microbiological and molecular diagnostic techniques have been developed and improved for M. catarrhalis, allowing the adequate determination and taxonomic positioning of this pathogen. Over the same period, studies have revealed its involvement in respiratory (e.g., sinusitis, otitis media, bronchitis, and pneumonia) and ocular infections in children and in laryngitis, bronchitis, and pneumonia in adults. The development of (molecular) epidemiological tools has enabled the national and international distribution of M. catarrhalis strains to be established, and has allowed the monitoring of nosocomial infections and the dynamics of carriage. Indeed, such monitoring has revealed an increasing number of Β-lactamase-positive M. catarrhalis isolates (now well above 90%), underscoring the pathogenic potential of this organism. Although a number of putative M. catarrhalis virulence factors have been identified and described in detail, their relationship to actual bacterial adhesion, invasion, complement resistance, etc. (and ultimately their role in infection and immunity), has been established in a only few cases. In the past 10 years, various animal models for the study of M. catarrhalis pathogenicity have been described, although not all of these models are equally suitable for the study of human infection. Techniques involving the molecular manipulation of M. catarrhalis genes and antigens are also advancing our knowledge of the host response to and pathogenesis of this bacterial species in humans, as well as providing insights into possible vaccine candidates. This review aims to outline our current knowledge of M. catarrhalis, an organism that has evolved from an emerging to a well-established human pathogen.


2016 ◽  
Vol 710 ◽  
pp. 409-414 ◽  
Author(s):  
Gianfranco De Matteis ◽  
Giuseppe Brando

This paper aims at providing an overview on the current state of the art and on possible future developments concerning the component method implementation for the classification of beam-to-column joints belonging to aluminum moment resisting frames.After a brief discussion on the component method theoretical bases, developed in the past to give a feasible calculation procedure for steel joints, recent experimental and numerical studies, carried out for investigating some aluminum components, are presented and discussed. In particular strengths and weaknesses of the current knowledge are put into evidence, also in light of the peculiarities that make aluminum alloys different from steel. The launch of new research fields, aimed at pursuing an update of the current codes dealing with aluminum structures, is therefore proposed.


Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 604
Author(s):  
Laura Vanderwaeren ◽  
Rüveyda Dok ◽  
Kevin Verstrepen ◽  
Sandra Nuyts

Clinical use of proton radiation has massively increased over the past years. The main reason for this is the beneficial depth-dose distribution of protons that allows to reduce toxicity to normal tissues surrounding the tumor. Despite the experience in the clinical use of protons, the radiobiology after proton irradiation compared to photon irradiation remains to be completely elucidated. Proton radiation may lead to differential damages and activation of biological processes. Here, we will review the current knowledge of proton radiobiology in terms of induction of reactive oxygen species, hypoxia, DNA damage response, as well as cell death after proton irradiation and radioresistance.


PEDIATRICS ◽  
1973 ◽  
Vol 52 (4) ◽  
pp. 586-600
Author(s):  
David H. Smith ◽  
David L. Ingram ◽  
Arnold L. Smith ◽  
Floyd Gilles ◽  
M. J. Bresnan

Prior to the introduction of specific antibacterial therapy, bacterial meningitis was a disease with a universally fatal or disastrous outcome. The introduction of typespecific antiserum, and then of the antibacterial drugs, improved this situation dramatically. Improvements in the general medical care of acutely ill children, and the introduction of a series of more potent antibiotics against its bacterial causes helped to generate an attitude that bacterial meningitis was, or soon would be, a disease of the past. The experience of the past two decades belies this thesis. Today, interest in many facets of this disease has been renewed by many physicians concerned with the health of children: the epidemiology, pathophysiology, diagnosis, and treatment. This symposium attempts to summarize for the practitioner the highlights of current knowledge in this area, and to outline certain areas in which recent advances can be anticipated, or will be studied. Tuberculous meningitis will be omitted for the sake of brevity, as will the special problems of meningitis in the newborn infant. There has been a resurgence of interest in developing vaccines to prevent Hemophilus influenzae b, pneumococcal, and meningococcal Group A, B, and C meningitis. These organisms cause almost all the bacterial meningitis after the first two months of life. If, as now seems possible, vaccines against most or all of these organisms will soon become available, those children having the greatest risk must be defined to determine who, and at what age should have priority in receiving the vaccine(s). A. THE CURRENT MAGNITUDE OF THE PROBLEM


2005 ◽  
Vol 29 (2) ◽  
pp. 139-155 ◽  
Author(s):  
Stefan Grab

Miniature varieties of cryogenic mounds that are capable of forming in seasonally frozen ground are commonly referred to as earth hummocks (e.g., North America), thúfur (e.g., Greenland and Iceland) and pounus (Fennoscandia). Over the past few decades there has been a consistent interest to study earth hummocks from a variety of environmental settings. This review summarizes the current knowledge of earth hummocks, highlighting aspects on the external and internal morphology, and thermal characteristics, which may assist to explain hummock formation. Several hypotheses have been proposed for the genesis of earth hummocks, including the ‘cryoexpulsion’ of clasts, hydrostatic and cryostatic pressure, cellular circulation, and differential frost heave. These hypotheses are critically evaluated and some research gaps identified. It emerges that considerable advances have been made towards an improved understanding of earth hummock development, modification and disintegration. Much progress has been made in the application of earth hummock studies to a variety of environmental research approaches such as palaeoenvironmental reconstructions and assessing their impact on hillslope drainage.


2019 ◽  
Vol 45 (1) ◽  
Author(s):  
Carlotta Spagnoli ◽  
Susanna Rizzi ◽  
Grazia Gabriella Salerno ◽  
Daniele Frattini ◽  
Carlo Fusco

Abstract Background Pathogenic variants in KIF1A (kinesin family member 1A) gene have been associated with hereditary spastic paraplegia (HSP) type 30 (SPG30), encopassing autosomal dominant and recessive, pure and complicated forms. Case presentation We report the long-term follow-up of a 19 years-old boy first evaluated at 18 months of age because of toe walking and unstable gait with frequent falls. He developed speech delay, mild intellectual disability, a slowly progressive pyramidal syndrome, microcephaly, bilateral optic subatrophy and a sensory axonal polyneuropathy. Brain MRI showed cerebellar atrophy, stable along serial evaluations (last performed at 18 years of age). Targeted NGS sequencing disclosed the de novo c.914C > T missense, likely pathogenic variant on KIF1A gene. Conclusions We report on a previously unpublished de novo heterozygous likely pathogenic KIF1A variant associated with slowly progressive complicated SPG30 and stable cerebellar atrophy on long-term follow-up, adding to current knowledge on this HSP subtype.


Zootaxa ◽  
2022 ◽  
Vol 5087 (1) ◽  
pp. 35-58
Author(s):  
ANDRÉS A. SALAZAR-FILLIPPO ◽  
LADISLAV MIKO

This checklist of oribatid mites of the Republic of Colombia compiles and provides a taxonomic update of all records known up to 2020. It includes 192 entries accounting for 68 named and 47 unnamed species belonging to 73 genera and 58 families of non-astigmatid oribatid mites. Specimens from the brachypyline supercohort were dominant (54.7%), followed by Mixonomata (30.7%). However, current knowledge is far from being complete and distribution patterns show large gaps throughout the country due to this lacking knowledge and most existing investigations only include group specific studies that prevent from any conclusions regarding the real community composition of oribatids in Colombia. From 32 political-administrative departments, oribatids have been reported in 20, but 5 account for 65% of the records. These are: Cundinamarca -including Bogotá D.C.- (24.4%), Magdalena (21.8%), Nariño (6.3%), La Guajira (6.3%), and Quindío (5.9%). Whereas most oribatid reports in the Neotropical region have taken place during the past five decades, a map presented in this document shows that Colombia still lags behind other Latin American countries. Mexico, Argentina, and Brazil, for instance, have reported the highest number of species for the region and are the only nations that possess national oribatid checklists in Latin America. The current work represents a national baseline of oribatids encouraging further study of this clearly underrepresented group.  


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