The cleft ion fountain: a two-dimensional kinetic model

The transport of ionospheric ions from a source in the polar cleft ionosphere through the polar magnetosphere is investigated using a two-dimensional, kinetic, trajectory-based code. The transport model includes the effects of gravitation, longitudinal magnetic gradient force, convection electric fields, and parallel electric fields. Individual ion trajectories as well as distribution functions and resulting bulk parameters of density, parallel average energy, and parallel flux for a presumed cleft ionosphere source distribution are presented for various conditions to illustrate parametrically the dependences on source energies, convection electric field strengths, ion masses, and parallel electric field strengths. The essential features of the model are consistent with the concept of a cleft-based ion fountain supplying ionospheric ions to the polar magnetosphere, and the resulting plasma distributions and parameters are in general agreement with recent low-energy ion measurements from the DE 1 satellite.

Alternative generation of CNS neural stem cells and PNS derivatives from neural crest-derived peripheral stem cells

Neural crest-derived stem cells (NCSCs) from the embryonic peripheral nervous system (PNS) can be reprogrammed in neurosphere (NS) culture to rNCSCs that produce central nervous system (CNS) progeny, including myelinating oligodendrocytes. Using global gene expression analysis we now demonstrate that rNCSCs completely lose their previous PNS characteristics and acquire the identity of neural stem cells derived from embryonic spinal cord. Reprogramming proceeds rapidly and results in a homogenous population of Olig2-, Sox3-, and Lex-positive CNS stem cells. Low-level expression of pluripotency inducing genes Oct4, Nanog, and Klf4 argues against a transient pluripotent state during reprogramming. The acquisition of CNS properties is prevented in the presence of BMP4 (BMP NCSCs) as shown by marker gene expression and the potential to produce PNS neurons and glia. In addition, genes characteristic for mesenchymal and perivascular progenitors are expressed, which suggests that BMP NCSCs are directed toward a pericyte progenitor/mesenchymal stem cell (MSC) fate. Adult NCSCs from mouse palate, an easily accessible source of adult NCSCs, display strikingly similar properties. They do not generate cells with CNS characteristics but lose the neural crest markers Sox10 and p75 and produce MSC-like cells. These findings show that embryonic NCSCs acquire a full CNS identity in NS culture. In contrast, MSC-like cells are generated from BMP NCSCs and pNCSCs, which reveals that postmigratory NCSCs are a source for MSC-like cells up to the adult stage.

Before transparency: control and communication in Early-Modern Europe

Today, transparency is hailed as a key to good governance and economic efficiency, with national states implementing new laws to allow citizens access to information. It is therefore paradoxical that, as shown by a series of crises and scandals, modern governments and international agencies frequently have paid only lip-service to such ideals. Since Jeremy Bentham first introduced the concept of transparency into the language in 1789, few societal debates have sparked so much interest within the academic community, and across a variety of disciplines, using different approaches and methodologies. Within these current debates, however, one fact is striking: the lack of historical reflection about the development of the concept of transparency, both as a principle and as applied in practice, prior to its inception. Accordingly, the aim of this special issue is to contribute to historicising the ways in which communication and control over fiscal policy and state finances operated in early modern European polities.

Schilbach-Rott/blepharofacioskeletal syndrome in a Brazilian patient

We report on a 4-year-old girl with blepharophimosis, a typical facial gestalt and skeletal abnormalities seen in the blepharofacioskeletal syndrome (BFSS). A comparative review with previous cases provides further evidence that BFSS and Schilbach-Rott syndrome (SRS) are the same condition. (C) 2008 Wiley-Liss, Inc.

SEM and Neurohistological Observations of Nerve Endings in the Middle Region of the Tongue of the Collared Peccary (Tayassu tajacu): A Silver Impregnation Method

The presence of lingual papillae and the nerve endings in the middle region of the tongue mucosa of collared peccary (Tayassu tajacu) were studied using scanning electron microscopy and light microscopy, based upon the silver impregnation method. The middle region of tongue mucosa revealed numerous filiform and fungiform papillae. The thick epithelial layer showed epithelial cells and a dense connective tissue layer containing nerve fibre bundles and capillaries. The sensory nerve endings, intensely stained by silver impregnation, were usually non-encapsulated and extended into the connective tissue of the filiform and fungiform papillae very close to the epithelial cells. In some regions, the sensory nerves fibres formed a dense and complex network of fine fibrils. The presence of these nerve fibrils may characterize the mechanisms of transmission of sensitive impulses to the tongue mucosa.

Molecular Basis of the Thermostability and Thermophilicity of Laminarinases: X-ray Structure of the Hyperthermostable Laminarinase from Rhodothermus marinus and Molecular Dynamics Simulations

Glycosyl hydrolases are enzymes capable of breaking the glycosidic linkage of polysaccharides and have considerable industrial and biotechnological applications. Driven by the later applications, it is frequently desirable that glycosyl hydrolases display stability and activity under extreme environment conditions, such as high temperatures and extreme pHs. Here, we present X-ray structure of the hyperthermophilic laminarinase from Rhodothermus marinus (RmLamR) determined at 1.95 angstrom resolution and molecular dynamics simulation studies aimed to comprehend the molecular basis, for the thermal stability of this class of enzymes. As most thermostable proteins, RmLamR contains a relatively large number of salt bridges, which are not randomly distributed on the structure. On the contrary, they form clusters interconnecting beta-sheets of the catalytic domain. Not all salt bridges, however, are beneficial for the protein thermostability: the existence of charge-charge interactions permeating the hydrophobic core of the enzymes actually contributes to destabilize the structure by facilitating water penetration into hydrophobic cavities, as can be seen in the case of mesophilic enzymes. Furthermore, we demonstrate that the mobility of the side-chains is perturbed differently in each class of enzymes. The side-chains of loop residues surrounding the catalytic cleft in the mesophilic laminarinase gain mobility and obstruct the active site at high temperature. By contrast, thermophilic laminarinases preserve their active site flexibility, and the active-site cleft remains accessible for recognition of polysaccharide substrates even at high temperatures. The present results provide structural insights into the role played by salt-bridges and active site flexibility on protein thermal stability and may be relevant for other classes of proteins, particularly glycosyl hydrolases.

Características acústicas da oclusiva glotal associada à sequência de Pierre Robin: estudo de caso

A fissura de palato, em associação à Sequência de Pierre Robin, pode favorecer o desenvolvimento de produções atípicas (compensatórias), na fala da criança, como é o caso da oclusiva glotal (golpe de glote) comumente observada em substituição aos sons oclusivos (vozeados ou não). No presente estudo, foi realizada a análise dos parâmetros fonético-acústicos da oclusiva glotal produzidas em /k/ e /g/ por uma criança do gênero feminino, com 5 anos, que apresentava fissura de palato reparada, associada à Sequência de Pierre Robin. Para isso, foram selecionadas seis palavras em que a oclusiva velar encontrava-se na posição inicial da palavra e combinada com as vogais /a/, /i/ e /u/ na posição acentuada. Foi ainda realizado julgamento perceptivo-auditivo por três fonoaudiólogos, que apresentou concordância quanto à presença da oclusiva glotal de 100% para ambas as relações (intra e inter-juízes). Na inspeção dos dados via espectrograma foi observada variabilidade dos parâmetros espectrais (burst e transição formântica) e essas variações também puderam ser computadas considerando as vogais separadamente. A análise estatística revelou diferença estatisticamente significante entre as duas consoantes velares (/k/ e /g/) nos parâmetros espectral (burst), temporal (VOT e duração relativa da oclusiva na palavra) e os relativos às características acústicas das vogais adjacentes às oclusivas (período estacionário de F3). Por fim, as características acústicas da oclusiva glotal sugeriram que a criança pode ter utilizado de estratégias para marcar contrastes fônicos na língua, ainda que os mesmos não tenham magnitude suficiente para serem resgatados auditivamente pelo ouvinte.

Electromyographic analysis of the superior belly of the omohyoid muscle and anterior belly of the digastric muscle in tongue and head movements

The participation of the superior belly of the omohyoid muscle and anterior belly of the digastric muscle in tongue and head movements was studied eletromyographically in 20 normal young volunteers. A pair of monopolar electrodes was used in each muscle for simultaneous recording of their actions. The muscles act in the following tongue movements: protrusion, right and left lateral movements, placement of the tip of the tongue on soft and hard palates and on the floor of the mouth. The strongest levels of activity of the superior belly of the omohyoid muscle were observed in the placement of the tip of the tongue on the soft palate, coincidentally with a greater dislocation of hyoid bone. Both of the muscles studied did not participate in the head's kinesiology. (C) 1999 Elsevier B.V. Ltd. All rights reserved.

Porencephaly and cortical dysplasia as cause of seizures in a dog

Background: Seizures are a common problem in small animal neurology and it may be related to underlying diseases. Porencephaly is an extremely rare disorder, and in Veterinary Medicine it affects more often ruminants, with only few reports in dogs.Case presentation: A one-year-old intact male Shih-Tzu dog was referred to Veterinary University Hospital with history of abnormal gait and generalized tonic-clonic seizures. Signs included hypermetria, abnormal nystagmus and increased myotatic reflexes. At necropsy, during the brain analysis, a cleft was observed in the left parietal and occipital lobes, creating a communication between the subarachnoid space and the left lateral ventricle, consistent with porencephaly; and also a focal atrophy of the caudal paravermal and vermal portions of the cerebellum. Furthermore, the histological examination showed cortical and cerebellar neuronal dysplasia.Conclusions: Reports of seizures due to porencephaly are rare in dogs. In this case, the dog presented a group of brain abnormalities which per se or in assemblage could result in seizure manifestation.

Celecoxib treatment does not alter recruitment and activation of osteoclasts in the initial phase of experimental tooth movement

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

An alternative technique to the harvesting of a connective tissue graft from a thin palate: Enhanced wound healing

This article describes an alternative surgical approach to the harvesting of subepithelial connective tissue grafts from thin palates. A partial-thickness flap is raised, and a graft composed of epithelium and connective tissue is removed from the palate. The superficial layer ( epithelium and a thin zone of connective tissue) is then dissected from the graft and replaced at the donor site to facilitate faster healing. The subjacent layer of connective tissue is placed as needed to obtain root coverage. The clinical application of this technique is described in two patients with multiple gingival recessions.

Prosthetic Treatments for Patients With Oronasal Communication

The prosthetic treatments play a role in the rehabilitation of patients with congenital and acquired cleft palate. To prepare the surgical field and/or correct inevitable sequelae of the surgery, the rehabilitation with obturator prosthesis is an auxiliary or complementary treatment to surgical treatments. In cases where the surgical treatment is contraindicated, the prosthetic rehabilitation becomes a definitive treatment. The denture is planned and fabricated according to each patient. Therefore, the aim of this study was to discuss the prosthetic rehabilitation performed in patients with oronasal communication.

Maxillo-mandibular counter-clockwise rotation and mandibular advancement with TMJ Concepts (R) total joint prostheses Part IV - Soft tissue response

The purpose of this Study was to evaluate Soft tissue response to rnaxillo-mandibular counter-clockwise rotation, with TMJ reconstruction and mandibular advancement using TMJ Concepts (R) total joint prostheses, and maxillary osteotomies in 44 females. All patients were operated at Baylor University Medical Center, Dallas TX, USA, by one Surgeon (Wolford). Eighteen patients had genioplasties with either porous block hydroxyapatite or hard tissue replacement implants (Group 2) 26 had no genioplasty (Group 1). Surgically, the maxilla moved forward and upward by counter-clockwise maxillo-mandibular rotation with greater horizontal movement in Group 2. Vertically, both groups showed diversity of maxillo-mandibular mean movement. Group I showed a consistent 1:0.97 ratio of hard to soft tissue advancement at pogonion; Group 2 results were less consistent, with ratios between 1:0.84 and 1:1.02. Horizontal changes in upper lip morphology after maxillary advancement/impaction, VY closure, and alar base cinch sutures showed greater movement in both groups, than observed in hard tissue. Counter-clockwise rotation of the maxillo-mandibular complex using TMJ Concepts total joint prostheses resulted in similar soft tissue response as previously reported for traditional maxillo-mandibular advancement without counter-clockwise rotation of the occlusal plane. The association of chin implants, in the present sample, showed higher variability of soft tissue response.

IGFR-I expression and structural analysis of the hard palatine mucosa in an ethanol-drinking rat strain (UChA and UChB)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)