Effects of B Cell Depletion by CD19-Targeted Chimeric Antigen Receptor T Cells in a Murine Model of Systemic Sclerosis.

OBJECTIVE: Our goal was to study the tolerance and efficacy of two B cell depletion strategies, including one with CD19-targeted chimeric antigen receptor (CAR) T cells, in a preclinical model mimicking the severe lung damages observed in systemic sclerosis. METHODS: B cell depletion strategies were evaluated in the Fra-2 transgenic (Tg) mouse model. We considered a first group of 16 untreated mice, a second group of 15 mice receiving a single dose of anti-CD20 monoclonal antibody (mAb), and a third group of 8 mice receiving CD19-targeted CAR-T cells in combination with anti-CD20 monoclonal antibody. After six weeks of clinical evaluation, different validated markers of inflammation, lung fibrosis, and pulmonary vascular remodeling were assessed. RESULTS: CD19-targeted CAR-T cells infusion in combination with anti-CD20 mAb resulted in a deeper B cell depletion than anti-CD20 mAb alone in the peripheral blood and lesional lungs of Fra-2 Tg mice. CAR-T cell infusion worsened the clinical score and increased mortality in Fra-2 Tg mice. In line with the above findings, CAR-T cell infusion significantly increased lung collagen content, the histological fibrosis score, and right ventricular systolic pressure. CAR-T cells accumulated in lesional lungs and promoted T activation and inflammatory cytokine production. Treatment with anti-CD20 mAb in monotherapy had no impact on lung inflammation-driven fibrosis and pulmonary hypertension. CONCLUSION: B cell therapies failed to show efficacy in the Fra2 Tg mice. The exacerbated Fra-2 lung inflammatory burden stimulated accumulation and expansion of activated CD19-targeted CAR-T cells, secondarily inducing T cell activation and systemic inflammation, finally leading to disease worsening.

[Preserving the oral health of patients on antiresorptive drugs]. / Préserver la santé orale des patients sous antirésorbeurs osseux.

PRESERVING THE ORAL HEALTH OF PATIENTS ON ANTIRESORPTIVE DRUGS. For many years, antiresorptive medication have proven their effectiveness in reducing the risk of pathological fractures in osteoporotic or tumoral bone. However, bisphosphonates and denosumab may, in rare cases, induce osteonecrosis of the jaw, especially when prescribed for malignant disease (bone metastases or multiple myeloma). The presence of oral infections and the performance of invasive procedures, particularly dental avulsions, increase the risk of this complication. The management of osteonecrosis of the jaw is complex, and the prescribing physician and the dental surgeon must implement preventive measures. There are numerous recommendations published by national and international scientific societies that guide practitioners in the oral management of these patients. An oral check-up and oral cavity restoration are strongly recommended before treatment, as well as the implementation of rigorous oral hygiene and regular visits to the dental surgeon. During and after treatment with antiresorptive medication, oral care protocols are used to reduce the risk of osteonecrosis of the jaws and, when it occurs, to manage it.

PRÉSERVER LA SANTÉ ORALE DES PATIENTS SOUS ANTIRÉSORBEURS OSSEUX. Depuis de nombreuses années, les antirésorbeurs osseux ont prouvé leur efficacité dans la diminution du risque de fracture pathologique sur os ostéoporotique ou tumoral. Parmi eux, les bisphosphonates et le dénosumab sont cependant susceptibles d'induire, dans de rares cas, une ostéonécrose des maxillaires, notamment lorsqu'ils sont prescrits pour une pathologie maligne (métastases osseuses ou myélome multiple). La présence de foyers infectieux bucco- dentaires et la réalisation de gestes invasifs, notamment des avulsions dentaires, augmentent le risque de cette complication. La prise en charge de l'ostéonécrose des maxillaires étant complexe, le médecin prescripteur et le chirurgien-dentiste doivent mettre en place des mesures préventives. Il existe de nombreuses recommandations éditées par des sociétés scientifiques nationales et internationales qui guident les praticiens dans la prise en charge bucco- dentaire de ces patients. Un bilan bucco-dentaire et une remise en état de la cavité buccale sont fortement recommandés avant la mise en place du traitement, ainsi que l'instauration d'une hygiène orale rigoureuse et de consultations régulières chez le chirurgien-dentiste. Pendant et après le traitement par antirésorbeurs osseux, des protocoles de soins bucco-dentaires permettent de diminuer le risque d'ostéonécrose des maxillaires et, lorsqu'elle survient, de la prendre en charge.

Knock-In of the Recurrent R368X Mutation of PRKAR1A that Represses cAMP-Dependent Protein Kinase A Activation: A Model of Type 1 Acrodysostosis.

In humans, activating mutations in the PRKAR1A gene cause acrodysostosis 1 (ACRDYS1). These mutations result in a reduction in PKA activation caused by an impaired ability of cAMP to dissociate mutant PRKAR1A from catalytic PKA subunits. Two striking features of this rare developmental disease are renal resistance to PTH and chondrodysplasia resulting from the constitutive inhibition of PTHR1/Gsa/AC/cAMP/PKA signaling. We developed a knock-in of the recurrent ACRDYS1 R368X PRKAR1A mutation in the mouse. No litters were obtained from [R368X]/[+] females (thus no homozygous [R368X]/[R368X] mice). In [R368X]/[+] mice, Western blot analysis confirmed mutant allele heterozygous expression. Growth retardation, peripheral acrodysostosis (including brachydactyly affecting all digits), and facial dysostosis were shown in [R368X]/[+] mice by weight curves and skeletal measurements (µCT scan) as a function of time. [R368X]/[+] male and female mice were similarly affected. Unexpected, however, whole-mount skeletal preparations revealed a striking delay in mineralization in newborn mutant mice, accompanied by a decrease in the height of terminal hypertrophic chondrocyte layer, an increase in the height of columnar proliferative prehypertrophic chondrocyte layer, and changes in the number and spatial arrangement of proliferating cell nuclear antigen (PCNA)-positive chondrocytes. Plasma PTH and basal urinary cAMP were significantly higher in [R368X]/[+] compared to WT mice. PTH injection increased urinary cAMP similarly in [R368X]/[+] and WT mice. PRKACA expression was regulated in a tissue (kidney not bone and liver) manner. This model, the first describing the germline expression of a PRKAR1A mutation causing dominant repression of cAMP-dependent PKA, reproduced the main features of ACRDYS1 in humans. It should help decipher the specificity of the cAMP/PKA signaling pathway, crucial for numerous stimuli. In addition, our results indicate that PRKAR1A, by tempering intracellular cAMP levels, is a molecular switch at the crossroads of signaling pathways regulating chondrocyte proliferation and differentiation. © 2016 American Society for Bone and Mineral Research.

A spatially-dense regression study of facial form and tissue depth: towards an interactive tool for craniofacial reconstruction.

Forensic Craniofacial Reconstruction (CFR) is an investigative technique used to illicit recognition of a deceased person by reconstructing the most likely face starting from the skull. A key component in most CFR methods are estimates of facial soft tissue depths (TD) at particular points (landmarks) on the skull based on averages from databases of TD recordings. These databases vary in their method of extraction, number and position of landmarks (usually sparse <100), condition of the body, population studied, and sub-categorization of the data. In this work a new dataset is presented in a novel manner based on 156 CT scans using a spatially-dense set (∼7500) of TD recordings to allow for a complete understanding of TD variation interpolating between typical landmarks. Furthermore, to unravel the interplay between soft-tissue layers, skull and facial morphology, TD and Facial Form (FF) are investigated both separately and combined. Using a partial least squares regression (PLSR) analysis, which allows for working with multivariate and spatially-dense data, on metadata of Sex, Age and BMI, different significant patterns on TD and FF variation were found. A similar, but with TD and FF combined, PLSR generated a model useful to report on both, in function of Sex, Age and BMI. In contrast to other datasets and due to the continuous nature of the regression there is no need for data sub-categorization. In further contrast, previous datasets have been presented in tabulated form, which is impractical for spatially-dense data. Instead an interactive tool was built to visualize the regression model in an accessible way for CFR practitioners as well as anatomists. The tool is free to the community and forms a base for data contributions to augment the model and its future use in practice.

Craniofacial reconstruction as a prediction problem using a Latent Root Regression model.

In this paper, we present a computer-assisted method for facial reconstruction. This method provides an estimation of the facial shape associated with unidentified skeletal remains. Current computer-assisted methods using a statistical framework rely on a common set of extracted points located on the bone and soft-tissue surfaces. Most of the facial reconstruction methods then consist of predicting the position of the soft-tissue surface points, when the positions of the bone surface points are known. We propose to use Latent Root Regression for prediction. The results obtained are then compared to those given by Principal Components Analysis linear models. In conjunction, we have evaluated the influence of the number of skull landmarks used. Anatomical skull landmarks are completed iteratively by points located upon geodesics which link these anatomical landmarks, thus enabling us to artificially increase the number of skull points. Facial points are obtained using a mesh-matching algorithm between a common reference mesh and individual soft-tissue surface meshes. The proposed method is validated in term of accuracy, based on a leave-one-out cross-validation test applied to a homogeneous database. Accuracy measures are obtained by computing the distance between the original face surface and its reconstruction. Finally, these results are discussed referring to current computer-assisted reconstruction facial techniques.

A comparative study of two methods of dental pulp extraction for genetic fingerprinting.

Extracting dental DNA for identification purposes is usually performed after crushing the tooth. The main disadvantage of this method is that the tooth is completely destroyed so further radiographic, anatomical or biochemical studies are no longer possible. We compared the quantities of DNA obtained by crushing the tooth and by removing pulp by standard endodontic access with trepanation of the occlusal surface and amplified DNA micro-satellites. In the series of crushed teeth, insufficient material for amplification was obtained in 78% of cases and a complete profile was obtained in only 9% of cases. Conversely, for the teeth prepared by trepanation, the profile was complete in 75% of cases and the DNA quantity was insufficient in only 3% of cases. Trepanation thus produced superior results in terms of quantity of DNA and the quality of the genetic profiles. Furthermore, it was a conservative procedure that allowed further analyses on the tooth.

A local technique based on vectorized surfaces for craniofacial reconstruction.

In this paper, we focus on the automation of facial reconstruction. Since they consider the whole head as the object of interest, usual reconstruction techniques are global and involve a large number of parameters to be estimated. We present a local technique which aims at reaching a good trade-off between bias and variance following the paradigm of non-parametric statistics. The estimation is localized on patches delimited by surface geodesics between anatomical points of the skull. The technique relies on a continuous representation of the individual surfaces embedded in the vectorial space of extended normal vector fields. This allows to compute deformations and averages of surfaces. It consists in estimating the soft-tissue surface over patches. Using a homogeneous database described in [31], we obtain results on the chin and nasal regions with an average error below 1mm, outperforming the global reconstruction techniques.

Construction and analysis of a head CT-scan database for craniofacial reconstruction.

This paper is devoted to the construction of a complete database which is intended to improve the implementation and the evaluation of automated facial reconstruction. This growing database is currently composed of 85 head CT-scans of healthy European subjects aged 20-65 years old. It also includes the triangulated surfaces of the face and the skull of each subject. These surfaces are extracted from CT-scans using an original combination of image-processing techniques which are presented in the paper. Besides, a set of 39 referenced anatomical skull landmarks were located manually on each scan. Using the geometrical information provided by triangulated surfaces, we compute facial soft-tissue depths at each known landmark positions. We report the average thickness values at each landmark and compare our measures to those of the traditional charts of [J. Rhine, C.E. Moore, Facial Tissue Thickness of American Caucasoïds, Maxwell Museum of Anthropology, Albuquerque, New Mexico, 1982] and of several recent in vivo studies [M.H. Manhein, G.A. Listi, R.E. Barsley, et al., In vivo facial tissue depth measurements for children and adults, Journal of Forensic Sciences 45 (1) (2000) 48-60; S. De Greef, P. Claes, D. Vandermeulen, et al., Large-scale in vivo Caucasian facial soft tissue thickness database for craniofacial reconstruction, Forensic Science International 159S (2006) S126-S146; R. Helmer, Schödelidentifizierung durch elektronische bildmischung, Kriminalistik Verlag GmbH, Heidelberg, 1984].

A study of the vascularization of the auricle by dissection and diaphanization.

The vascularization of the auricle is poorly documented, despite the developments in auriculotherapy and reconstructive surgery. The aim of this study was to describe its arterial distribution using two techniques: diaphanization and anatomical dissection. The study was conducted after intravascular injection of eight diaphanized auricles and ten that were dissected. Dissection showed that the auricle is vascularized by an anterior flow arising in the superficial temporal artery and also by a posterior flow arising in the posterior auricular artery in eight cases out of ten, and in the occipital artery in the remaining two. Diaphanization revealed the three-dimensional arterial distribution of preserved specimens. This technique has a didactic use to complement to standard anatomical dissection.

Gradual and safe technique for sinus floor elevation using trephines and osteotomes with stops: a cadaveric anatomic study.

OBJECTIVE: The aim of this study was to develop a new technique for maxillary sinus floor elevation through the crestal approach, using trephines and osteotomes with stops, and to assess the risk of sinus membrane lesion. STUDY DESIGN: The study was performed on 30 heads removed from fresh nonpreserved cadavers with subsinus bone height >or=5 mm. The anatomic specimens were sectioned axially on a plane passing 1 cm below the infraorbital foramen, to be able to see and film the sinus floor covered by the membrane. A total of 112 implants were placed using this technique (48 without grafting material and 64 with grafting material). RESULTS: Using this technique, we obtained a 4-6 mm elevation of the sinus membrane without impairing the mucosa. In the 13 cases where membrane lesions were observed, 9 had been performed without grafting material. The greater the initial subsinus bone height, the higher the elevation observed. CONCLUSIONS: The success of this technique was due to stops on the trephines and osteotomes, which reduced the risk of invading the sinus cavity and made it possible to lift the membrane gently, fully controlling movements. This technique is indicated for large crests of type III or IV bone and with a minimal bone height of 5 mm.