Localization of proliferating cell nuclear antigen-immunoreactivity in human dental pulp and gingiva

The proliferating cell nuclear antigen (PCNA) is regarded as an operational marker of proliferating cells. We have used PC10 monoclonal antibody to PCNA to reveal proliferation sites in human dental pulp and gingiva. Intense PCNA-immunoreactivity was observed in the basal layer of the gingiva lining epithelium and within some cells of the underlying connective tissues, including some endothelial and perivascular cells. PCNA-reactive cells were scattered throughout the pulp tissue, but were particularly numerous in the peripheral part. Since PCNA is an endogenous cell cycle-related molecule, we propose that PCNA-antibodies may represent useful tools for studying cell kinetics in human oral tissues in normal as well as pathological situations, such as tumors, wound healing and inflammation.L’antigène nucléaire de la prolifération cellulaire (PCNA) est considéré comme un marqueur de la prolifération cellulaire. Nous avons utilisé l’anticorps monoclonal PC10 pour le PCNA afin de mettre en évidence les sites de prolifération dans la pulpe dentaire humaine et dans la gencive. Une immunoréactivité intense pour le PCNA a été observée au niveau de la couche basale de l’épithélium gingival et dans certaines cellules du conjonctif sous-jacent, comprenant des cellules endothéliales et des cellules perivasculaires. Les cellules PCNA-réactives sont dispersées dans la pulpe, mais sont particulièrement nombreuses dans les portions de la périphérie. Etant donné que le PCNA est une molécule endogène en liaison avec le cycle cellulaire, nous proposons que les anticorps antiPCNA peuvent constituer un excellent moyen pour étudier les cinétiques cellulaires dans les tissus oraux humains aussi bien dans des situations normales que pathologiques telles que tumeurs, cicatrisation des plaies et inflammation.

On-orbit assembly using superquadric potential fields

The autonomous on-orbit assembly of a large space structure is presented using a method based on superquadric artificial potential fields. The final configuration of the elements which form the structure is represented as the minimum of some attractive potential field. Each element of the structure is then considered as presenting an obstacle to the others using a superquadric potential field attached to the body axes of the element. A controller is developed which ensures that the global potential field decreases monotonically during the assembly process. An error quaternion representation is used to define both the attractive and superquadric obstacle potentials allowing the final configuration of the elements to be defined through both relative position and orientation. Through the use of superquadric potentials, a wide range of geometric objects can be represented using a common formalism, while collision avoidance can make use of both translational and rotation maneuvers to reduce total maneuver cost for the assembly process

Experimental Demonstration of In-Field 400G Coherent Metro-Access Convergence

We present an experimental demonstration and analytical scaling of optically amplified metro combined with PON access transmission over installed fibers, using coherent 50GBaud PM-16QAM and discuss the technical feasibility of future 400G metro-access convergenc

Immunocytochemical labelling of Merkel cells of human oral mucosa by means of antibodies to protein gene product 9.5

Merkel cell (MC) are one of the non-keratinocyte cell populations that reside in oral epithelium. Protein gene product 9.5 (PGP 9.5) is a protein specifically present in the cytoplasm of neurons and neuroendocrine cells. It is demonstrated by immunofluorescence and immunoperoxidase that MC of oral human mucosa express PGP 9.5-like immunoreactivity. This finding is in agreement with the hypothesis that oral MC are paraneurons or neuroendocrine cells. The use of anti-PGP 9.5 serum may be of value for future studies of MC in normal and pathological oral tissues.Les cellules de Merkel (MC) représentent une des populations cellulaires différentes des Kératinocytes qui résident dans les épithéliums de la cavité orale. Le Protein Gene Product 9.5 (PGP 9.5) est une protéine présente, de façon spécifique, dans les neurones et dans les cellules neuroendocrines. On démontre ici, en utilisant les techniques d’immunofluorescence et d’immunopéroxydase, que les MC de la muqueuse orale humaine présentent une immunoréactivité au PGP 9.5. Cette observation est en accord avec l’hypothèse que les MC de la cavité orale sont des paraneurones ou cellules neuroendocrines. L’emploi d’antisérums anti PGP 9.5 peut être utile pour d’ultérieures études sur les MC dans les tissus de la cavité orale aussi bien en conditions normales qu’en conditions pathologiques

Cell kinetics in a model of artificial skin. An immunohistochemical and flow cytometric analysis

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Etude immunocytochimique du développement de la cavité buccale du rat

Flow cytometry and autoradiography are extensively used for the evaluation of the number of cells in S-phase in order to study the proliferative activity within tissues and organs. The recent development of a monoclonal antibody against 5-bromo-2’deoxyuridine (BrdUrd), a nonradioactive thymidine analogue that is incorporated within DNA-synthetizing cells, allows the immunochemical detection of proliferating cells. The use of this antibody allows an immunocytochemical detection of proliferating cells «in situ» on tissue sections.We have applied this new technique for the identification of proliferating cells within the tooth and other organs of rat mouth during development. We believe that this technique, for its precision and simplicity, may be a powerful tool for studying the citokinetic and the differentiation of normal and neoplastic cells within the mouth as well as in other districts of the body.Afin d’évaluer avec précision la prolifération cellulaire dans un tissu ou un organe, on emploie couramment la cytofluorimétrie en flux ainsi que les techniques autoradiographiques, qui permettent d’obtenir des informations sur le nombre de cellules en phase S et par conséquent en prolifération.Récemment, de nouvelles techniques non autoradiographiques ont été mises au point pour l’identification des cellules en prolifération. Ces techniques exploitent l’incorporation de la 5-bromo-2’déoxyuridine (BrdUrd), analogue de la thymidine, dans le DNA en voie de duplication. Ces techniques utilisent un anticorps monoclonal dirigé contre la BrdUrd pour évaluer l’incorporation de cette dernière dans les cellules en phase S. L’emploi de cet anticorps en immunocytochimie permet une facile identification «in situ», sur des coupes de tissu, des cellules en prolifération.Nous avons utilisé ce procédé immunocytochimique pour repérer et identifier les cellules en prolifération dans la dent et dans d’autres organes de la cavité buccale du rat nouveau-né, organes qui sont donc encore en cours de développement. Nous estimons que la technique utilisée dans cette recherche peut constituer, par sa précision et sa simplicité, un instrument valable pour l’étude de la prolifération cellulaire ainsi que de la différenciation cellulaire dans les tissus de la dent et de la cavité buccale, aussi bien dans le domaine de l’organogenèse que dans celui de la pathologie tumorale

Autonomic nervous system responses to strength training in top-level weight lifters

In athletes, spectral analysis of HR variability (HRV) has been shown capable to detect the adaptational changes in sympatho-vagal control attending physical training. So far, studies investigated autonomic nervous system (ANS) changes occurring with endurance training, whereas adaptations to markedly different exercise modes, for example, strength training, have never been investigated. We assessed the changes in cardiac ANS parameters during long-term training in weight lifters of the Italian team preparing for the European Championship, where athletes competed for obtaining the pass for Olympic Games. We investigated nine athletes. Subject trained 3 sessions/day, 6 days a week. The intensity of strength exercises varied from 70% to 95% 1 RM. Training load (TL) was calculated as: volume (min)  7 intensity (%1RM).All ANS parameters were significantly and highly correlated on an individual basis to the dose of exercise with a second-order regression model (r2 ranged from 0.96 to 0.99; P < 0.001). The low-frequency (LF) component of HRV and LF/HF ratio showed an initial increase with the progression of TL and then a decrease, resembling a bell-shaped curve with a minimum at the highest TL. The high-frequency (HF) component of HRV and R-R interval showed a reciprocal pattern, with an initial decrease with progression of TL followed by an increase, resembling an U-shaped curve with a maximum at the highest TL. These adaptations were at the opposite to those previously reported in endurance athletes. These results suggest that in Olympic weight lifters, ANS adaptations to training are dose-related on individual basis and that ANS adaptations are mainly sport-specific