266 research outputs found
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.LâantigĂšne nuclĂ©aire de la prolifĂ©ration cellulaire (PCNA) est considĂ©rĂ© comme un marqueur de la prolifĂ©ration cellulaire. Nous avons utilisĂ© lâanticorps monoclonal PC10 pour le PCNA afin de mettre en Ă©vidence les sites de prolifĂ©ration dans la pulpe dentaire humaine et dans la gencive. Une immunorĂ©activitĂ© intense pour le PCNA a Ă©tĂ© observĂ©e au niveau de la couche basale de lâĂ©pithĂ©lium gingival et dans certaines cellules du conjonctif sous-jacent, comprenant des cellules endothĂ©liales et des cellules perivasculaires. Les cellules PCNA-rĂ©actives sont dispersĂ©es dans la pulpe, mais sont particuliĂšrement nombreuses dans les portions de la pĂ©riphĂ©rie. Etant donnĂ© que le PCNA est une molĂ©cule endogĂšne en liaison avec le cycle cellulaire, nous proposons que les anticorps antiPCNA peuvent constituer un excellent moyen pour Ă©tudier les cinĂ©tiques cellulaires dans les tissus oraux humains aussi bien dans des situations normales que pathologiques telles que tumeurs, cicatrisation des plaies et inflammation.
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) reprĂ©sentent une des populations cellulaires diffĂ©rentes des KĂ©ratinocytes qui rĂ©sident dans les Ă©pithĂ©liums de la cavitĂ© orale. Le Protein Gene Product 9.5 (PGP 9.5) est une protĂ©ine prĂ©sente, de façon spĂ©cifique, dans les neurones et dans les cellules neuroendocrines. On dĂ©montre ici, en utilisant les techniques dâimmunofluorescence et dâimmunopĂ©roxydase, que les MC de la muqueuse orale humaine prĂ©sentent une immunorĂ©activitĂ© au PGP 9.5. Cette observation est en accord avec lâhypothĂšse que les MC de la cavitĂ© orale sont des paraneurones ou cellules neuroendocrines. Lâemploi dâantisĂ©rums anti PGP 9.5 peut ĂȘtre utile pour dâultĂ©rieures Ă©tudes sur les MC dans les tissus de la cavitĂ© orale aussi bien en conditions normales quâen conditions pathologiques
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
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-2âdeoxyuridine (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 dâĂ©valuer avec prĂ©cision la prolifĂ©ration cellulaire dans un tissu ou un organe, on emploie couramment la cytofluorimĂ©trie en flux ainsi que les techniques autoradiographiques, qui permettent dâobtenir des informations sur le nombre de cellules en phase S et par consĂ©quent en prolifĂ©ration.RĂ©cemment, de nouvelles techniques non autoradiographiques ont Ă©tĂ© mises au point pour lâidentification des cellules en prolifĂ©ration. Ces techniques exploitent lâincorporation de la 5-bromo-2âdĂ©oxyuridine (BrdUrd), analogue de la thymidine, dans le DNA en voie de duplication. Ces techniques utilisent un anticorps monoclonal dirigĂ© contre la BrdUrd pour Ă©valuer lâincorporation de cette derniĂšre dans les cellules en phase S. Lâemploi de cet anticorps en immunocytochimie permet une facile identification «in situ», sur des coupes de tissu, des cellules en prolifĂ©ration.Nous avons utilisĂ© ce procĂ©dĂ© immunocytochimique pour repĂ©rer et identifier les cellules en prolifĂ©ration dans la dent et dans dâautres organes de la cavitĂ© buccale du rat nouveau-nĂ©, organes qui sont donc encore en cours de dĂ©veloppement. Nous estimons que la technique utilisĂ©e dans cette recherche peut constituer, par sa prĂ©cision et sa simplicitĂ©, un instrument valable pour lâĂ©tude de la prolifĂ©ration cellulaire ainsi que de la diffĂ©renciation cellulaire dans les tissus de la dent et de la cavitĂ© buccale, aussi bien dans le domaine de lâorganogenĂšse 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
a sonographic quantitative cutoff value of cerebral venous outflow in neurologic diseases a blinded study of 115 subjects
BACKGROUND AND PURPOSE: The autonomic nervous system maintains constant cerebral venous blood outflow in changing positions. Alterations in cerebral autoregulation can be revealed by postural changes at quantitative color Doppler sonography. The aim of this study was to reach an optimal cutoff value of the difference between the cerebral venous blood outflow in the supine and seated positions that can discriminate healthy controls from patients with multiple sclerosis and those with other neurologic diseases and to evaluate its specificity, sensitivity, and diagnostic accuracy. MATERIALS AND METHODS: One hundred fifteen subjects (54 with MS, 31 healthy controls, 30 with other neurologic diseases) underwent a blinded quantitative color Doppler sonography evaluation of cerebral venous blood outflow in the supine and sitting positions. An optimal difference value between the supine and sitting positions of the cerebral venous blood outflow cutoff value was sought. RESULTS: The difference value between supine and sitting positions of the cerebral venous blood outflow was †503.24 in 38/54 (70.37%) patients with MS, 9/31 (29.03%) healthy controls, and 13/30 (43.33%) subjects with other neurological diseases. A difference value between supine and sitting positions of the cerebral venous blood outflow at a 503.24 cutoff reached a sensitivity at 70.37%, a 70.96% specificity, a 80.85% positive predictive value, and a 57.89% negative predictive value; the quantitative color Doppler sonography parameters yielded significant differences. The difference value between supine and sitting positions of cerebral venous blood outflow †503.24 assessed the significant difference between MS versus other neurological diseases. CONCLUSIONS: Alteration of cerebral venous blood outflow discriminated MS versus other neurologic diseases and MS versus healthy controls. The difference value between supine and sitting positions of cerebral venous blood outflow †503.24 was statistically associated with MS
Acute effects of whole-body vibrations on the fatigue induced by multiple repeated sprint ability test in soccer players
Background: We tested the hypothesis that whole-body vibration (WBV) positively affects the fatigue process ensuing from repeated bouts of maximal efforts, as induced by repeated sprints' ability (RSA). Eleven male soccer players performed three sets of six repeated shuttle sprints (40 meters).
Methods: Eleven male soccer players (age 23.6±4.5 years) were cross-randomized to perform WBW before RSA and during the recovery between sets (WBV-with) or to warm-up and passive recovery between sets (WBV-without). The effects of WBV were quantified by sprint time (ST) and blood lactate concentration (LA), collected up to 15 min after completion of tests.
Results: ST during RSA showed a better maintenance of performance in the WBV-with compared to WBV-without condition in all three sets, reaching a statistical significance between-groups during the 2nd and 3rd set (P<0.05). No significant differences in ST over the sets were detected in WBV-with, whereas a significant decrease was observed in the WBV-without condition (P<0.001). LA recovered significantly faster from the 9th to 15th minute of recovery in WBV-with as compared to WBV-without (P<0.05).
Conclusions: These findings would indicate that WBV performed during recovery between RSA sets can delay the onset of muscle fatigue resulting in a better maintenance of sprint performance
Long-term miR-669a therapy alleviates chronic dilated cardiomyopathy in dystrophic mice.
BACKGROUND: Dilated cardiomyopathy (DCM) is a leading cause of chronic morbidity and mortality in muscular dystrophy (MD) patients. Current pharmacological treatments are not yet able to counteract chronic myocardial wastage, thus novel therapies are being intensely explored. MicroRNAs have been implicated as fine regulators of cardiomyopathic progression. Previously, miR-669a downregulation has been linked to the severe DCM progression displayed by Sgcb-null dystrophic mice. However, the impact of long-term overexpression of miR-669a on muscle structure and functionality of the dystrophic heart is yet unknown.
METHODS AND RESULTS: Here, we demonstrate that intraventricular delivery of adeno-associated viral (AAV) vectors induces long-term (18 months) miR-669a overexpression and improves survival of Sgcb-null mice. Treated hearts display significant decrease in hypertrophic remodeling, fibrosis, and cardiomyocyte apoptosis. Moreover, miR-669a treatment increases sarcomere organization, reduces ventricular atrial natriuretic peptide (ANP) levels, and ameliorates gene/miRNA profile of DCM markers. Furthermore, long-term miR-669a overexpression significantly reduces adverse remodeling and enhances systolic fractional shortening of the left ventricle in treated dystrophic mice, without significant detrimental consequences on skeletal muscle wastage.
CONCLUSIONS: Our findings provide the first evidence of long-term beneficial impact of AAV-mediated miRNA therapy in a transgenic model of severe, chronic MD-associated DCM
Long-Term Clinical Consequences of Intense, Uninterrupted Endurance Training in Olympic Athletes
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