[Subcutaneous emphysema after dental or stomatological treatment, rare complications or consequences of malpractice ?] / Emphysèmes sous-cutanés après soins dentaires ou stomatologiques, rares complications ou conséquences d'une mauvaise pratique ?

The occurrence of pneumomediastinum and subcutaneous emphysema following oral treatment is the result of the inappropriate use of dental equipment using pressurised air. However, their use in oral surgery, including dental extractions, continues nowadays. In addition to being a source of subcutaneous and pneumomediastinum emphysema at risk of infection, pneumatic instrumentation can also be a source of potentially serious gas embolisms. A thorough knowledge of this type of complication by the practitioners and the proper use of the instrumentation will enable a significant reduction of the incidence of theses complications.

La survenue de pneumomédiastins et d'emphysèmes sous-cutanés à la suite de traitements buccaux est le résultat d'une utilisation inadéquate de matériels dentaires utilisant l'air pressurisé. Leur usage dans des soins de chirurgie orale, dont les extractions dentaires, persiste néanmoins à l'heure actuelle. En plus d'être pourvoyeur d'emphysèmes sous-cutanés et pneumomédiastin à risque de surinfection, l'instrumentation pneumatique peut également être la source d'embolies gazeuses potentiellement graves. Une connaissance approfondie de ce type de complications par les praticiens ainsi que la bonne utilisation de l'instrumentation permettront une réduction significative de leur incidence.

[Cervical spondylolysis : a rare fortuitous finding]. / Cas clinique. Spondylolyse cervicale : une découverte fortuite rare.

A young patient consulted in our physical and rehabilitation medicine department following the onset of pain on the scapula area and at the base of his right upper limb after carrying a heavy load. After a couple of weeks, the patient also developed cervical pain. Fortuitously, the cervical scanner displayed a right C6 spondylolysis. Further evaluation by bone scan confirmed that this lesion was not recent and so probably not the cause of the symptoms. Cervical isthmic spondylolysis is a rare condition, much more common at the lumbar level and often ignored at the cervical one. The etiology, pahophysiology, imaging and treatment options for this cervical pathology are discussed in this article.

Un jeune patient a consulté en médecine physique pour des douleurs aux niveaux de l'omoplate et de la racine du membre supérieur droit apparues suite au port d'une charge lourde. Après quelques semaines, le patient se plaignait également de cervicalgies. Un scanner du rachis cervical a objectivé fortuitement une spondylolyse C6 droite. Un bilan complémentaire par scintigraphie osseuse a révélé que la lésion était ancienne et qu'elle n'était probablement pas la cause de la symptomatologie. La lyse isthmique cervicale est une pathologie peu répandue. Très connue à l'étage lombaire, la spondylolyse est rare et souvent ignorée au niveau cervical. L'étiologie, la physiopathologie, l'imagerie et la prise en charge de cette pathologie cervicale sont discutées dans cet article.

[Role of physical and rehabilitation medicine in the aftermath of SARS-CoV-2 disease]. / Rôle de la médecine physique et réadaptation fonctionnelle dans les suites d'une atteinte au SARS-CoV-2.

2020 will be remembered as the year of SARS-CoV-2 pandemic which confined most of the world's population at home. Rehabilitation units will have to face specific challenges to protect the vulnerable in-patients. Moreover, they must prepare for post-COVID-19 patients who might suffer from illness consequences or present a post intensive care syndrome secondary to the increased ICU length of stay. The purpose of this paper is to highlight the deficiencies of post-COVID-19 patients and suggest a decision algorithm to best match their needs.

L'année 2020 restera marquée par la pandémie de SARS-CoV-2, originaire de Chine, qui a confiné une grande partie de la population mondiale. Les services de médecine physique et rééducation fonctionnelle ont dû adopter des mesures spécifiques afin de limiter la contagion de leurs patients, appartenant à la population à risque. Ils se préparent également à l'accueil et à la prise en charge des patients post-COVID-19 présentant des séquelles secondaires à l'infection ou à l'hospitalisation prolongée en réanimation, responsable d'un syndrome post-soins intensifs. L'objectif de cet article est de dégager les différentes pathologies auxquelles les médecins rééducateurs seront confrontés et de proposer un algorithme décisionnel pour orienter la prise en charge rééducative.

[Pathologies of the musculoskeletal system in diabetes mellitus]. / Les complications musculo-squelettiques du diabète.

Diabetes mellitus causes several micro- (nephropathy, neuropathy and retinopathy) and macro-vascular (coronary insufficiency, stroke, lower limb arteriopathy) complications. Some complications are less widely known, particularly the ones involving the musculoskeletal system. Even though diabetes is not specifically linked to these complications, it increases both their incidence and severity. The objective of this paper is to review the main musculoskeletal complications associated to diabetes. It describes the pathophysiology, symptomatology and treatments of these complications.

Le diabète sucré entraîne toute une série de complications micro- (néphropathie, rétinopathie et neuropathie) et macro-vasculaires (coronopathie, accident vasculaire cérébral et artériopathie des membres inférieurs). Certaines complications sont moins connues, notamment celles qui touchent le système musculo-squelettique. Ces pathologies ne sont pas spécifiques du diabète, mais celui-ci en augmente fortement, non seulement, l'incidence, mais aussi la sévérité. Le but du présent article est de revoir les principales complications musculo-squelettiques que l'on peut rencontrer chez les personnes diabétiques, en décrire la physiopathologie, la symptomatologie et le traitement à préconiser.

Treponema denticola peptidoglycan induces the production of inflammatory mediators and matrix metalloproteinase 9 in macrophage-like cells.

BACKGROUND AND OBJECTIVE: Treponema denticola is a key pathogen associated with periodontitis, a chronic inflammatory disease affecting tooth-supporting tissues. In the present study, we investigated the response of human macrophage-like cells to stimulation by peptidoglycan isolated from T. denticola. We also studied the effect of the peptidoglycan preparation on the phosphorylation state of kinases. MATERIAL AND METHODS: Monoblastic leukemia cells (U937 strain) were differentiated into adherent macrophage-like cells using phorbol myristic acid prior to being stimulated for 6 or 24 h with various amounts of T. denticola peptidoglycan. Secreted inflammatory mediators were quantified by enzyme-linked immunosorbent assays. The phosphorylation state of kinases was determined by immunoblotting. RESULTS: The T. denticola peptidoglycan preparation, which was non-toxic for macrophage-like U937 leukemia cells at the concentration used, significantly increased, in a dose-dependent manner, the secretion of the pro-inflammatory cytokines tumor necrosis factor alpha, interleukin-1beta and interleukin-6. It also increased the secretion of two potent chemokines, interleukin-8 (IL-8) and regulated on activation normal T cell expressed and secreted (RANTES). T. denticola peptidoglycan also induced a significant increase in the secretion of prostaglandin E(2) and matrix metalloproteinase 9 by macrophage-like cells. The phosphorylation state of several kinases, including extracellular regulated protein-serine kinase 2 (+99%), G protein-coupled receptor-serine kinase 2 (+50%), Yes-related protein-tyrosine kinase (+44%) and extracellular regulated protein-serine kinase 1 (+30%) also increased following stimulation with the peptidoglycan preparation. CONCLUSION: T. denticola peptidoglycan activates intracellular signaling pathways, leading to an increased production of inflammatory mediators by macrophage-like cells.

Potential oral health benefits of cranberry.

In the past decade, cranberry extracts have been attracting ever-growing attention by dental researchers. The potential benefits of cranberry components in reducing oral diseases, including dental caries and periodontitis, are discussed in this review. A non-dialysable cranberry fraction enriched in high molecular weight polyphenols has very promising properties with respect to cariogenic and periodontopathogenic bacteria, as well as to the host inflammatory response and enzymes that degrade the extracellular matrix. Cranberry components are potential anti-caries agents since they inhibit acid production, attachment, and biofilm formation by Streptococcus mutans. Glucan-binding proteins, extracellular enzymes, carbohydrate production, and bacterial hydrophobicity, are all affected by cranberry components. Regarding periodontal diseases, the same cranberry fraction inhibits host inflammatory responses, production, and activity of enzymes that cause the destruction of the extracellular matrix, biofilm formation, and adherence of Porphyromonas gingivalis, and proteolytic activities and coaggregation of periodontopathogens. The above-listed effects suggest that cranberry components, especially those with high molecular weight, could serve as bioactive molecules for the prevention and/or treatment of oral diseases.

Naringenin has anti-inflammatory properties in macrophage and ex vivo human whole-blood models.

BACKGROUND AND OBJECTIVE: Periodontitis is a chronic inflammatory disease of bacterial etiology, affecting tooth-supporting tissues. The host inflammatory response to periodontopathogens, notably the high and continuous production of cytokines, is considered a major factor causing the local tissue destruction observed in periodontitis. The aim of the present study was to investigate the effect of naringenin, a major flavanone in grapefruits and tomatoes, on the lipopolysaccharide-induced pro-inflammatory cytokine production by host cells, using two different models. MATERIAL AND METHODS: The effect of naringenin was characterized using macrophages stimulated with the lipopolysaccharide of either Aggregatibacter actinomycetemcomitans or Escherichia coli and using whole blood stimulated with A. actinomycetemcomitans lipopolysaccharide, in the presence or absence of naringenin. Lipopolysaccharide-induced interleukin-1 beta, interleukin-6, interleukin-8 and tumor necrosis factor-alpha production by macrophages and whole-blood samples treated with naringenin were evaluated using an enzyme-linked immunosorbent assay. Changes in the phosphorylation states of macrophage kinases induced by A. actinomycetemcomitans lipopolysaccharide and naringenin were characterized by immunoblot screening. RESULTS: Our results clearly indicated that naringenin is a potent inhibitor of the pro-inflammatory cytokine response induced by lipopolysaccharide in both macrophages and in whole blood. Naringenin markedly inhibited the phosphorylation on serines 63 and 73 of Jun proto-oncogene-encoded AP-1 transcription factor in lipopolysaccharide-stimulated macrophages. CONCLUSION: The results from the present study suggest that naringenin holds promise as a therapeutic agent for treating inflammatory diseases such as periodontitis.

Hemoglobin and LPS act in synergy to amplify the inflammatory response.

Vascular disruption and bleeding during periodontitis likely increase the levels of hemoglobin in gingival crevicular fluid. The aim of this study was to investigate the effect of hemoglobin on the inflammatory responses of human macrophages stimulated with lipopolysaccharides (LPS) isolated from periodontopathogens. The production of interleukin-1 beta (IL-1beta), IL-6, IL-8, and tumor necrosis factor alpha (TNF-alpha) by macrophages following challenges with Porphyromonas gingivalis and Fusobacterium nucleatum LPS in the presence or absence of human hemoglobin was analyzed by ELISA. The effect of hemoglobin on LPS-binding to macrophages was evaluated with (3)H-LPS. Hemoglobin and LPS from periodontopathogens acted in synergy to stimulate the production of high levels of IL-1beta, IL-6, IL-8, and TNF-alpha by macrophages. Hemoglobin also enhanced LPS-binding to macrophages. This study suggests that hemoglobin contributes to increases in the levels of pro-inflammatory mediators in periodontal sites by acting in synergy with LPS from periodontopathogens, thus favoring the progression of periodontitis.

Anti-inflammatory activity of a high-molecular-weight cranberry fraction on macrophages stimulated by lipopolysaccharides from periodontopathogens.

Periodontitis is a chronic inflammatory disease affecting oral tissues. The continuous, high production of cytokines by host cells triggered by periodontopathogens is thought to be responsible for the destruction of tooth-supporting tissues. Macrophages play a critical role in this host inflammatory response to periodontopathogens. The aim of this study was to investigate the effect of non-dialyzable material prepared from cranberry juice concentrate on the pro-inflammatory cytokine response of macrophages induced by lipopolysaccharides (LPS) from Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum subsp. nucleatum, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Escherichia coli. Interleukin-1 beta (IL-1beta), IL-6, IL-8, tumor necrosis factor alpha (TNF-alpha), and Regulated on Activation Normal T-cell Expressed and Secreted (RANTES) production by macrophages treated with the cranberry fraction prior to stimulation by LPS was evaluated by ELISA. Our results clearly indicate that the cranberry fraction was a potent inhibitor of the pro-inflammatory cytokine and chemokine responses induced by LPS. This suggests that cranberry constituents may offer perspectives for the development of a new therapeutic approach to the prevention and treatment of periodontitis.

Winter stem xylem pressure in walnut trees: effects of carbohydrates, cooling and freezing.

Pressure transducers were attached to twigs of orchard trees and potted trees of walnut (Juglans regia L.) to measure winter stem xylem pressures. Experimental potted trees were partially defoliated in the late summer and early autumn to lower the amount of stored carbohydrates. Potted trees were placed in cooling chambers and subjected to various temperature regimes, including freeze-thaw cycles. Xylem pressures were inversely proportional to the previous 48-h air temperature, but positively correlated with the osmolarity of the xylem sap. Defoliated trees had significantly lower concentrations of stored carbohydrates and significantly lower xylem sap osmolarities than controls. Plants kept at 1.5 degrees C developed xylem pressures up to 40 kPa, just 7% of the theoretical osmotic pressure of the xylem sap. However, exposure to low, nonfreezing temperatures followed by freeze-thaw cycles resulted in pressures over 210 kPa, which was 39% of the theoretical osmotic pressure. A simple osmotic model could account for the modest positive winter pressures at low, nonfreezing temperatures, but not for the synergistic effects of freeze-thaw cycles.

Seasonal variation in xylem pressure of walnut trees: root and stem pressures.

Measurements of air and soil temperatures and xylem pressure were made on 17-year-old orchard trees and on 5-year-old potted trees of walnut (Juglans regia L.). Cooling chambers were used to determine the relationships between temperature and sugar concentration ([glucose] + [fructose] + [sucrose], GFS) and seasonal changes in xylem pressure development. Pressure transducers were attached to twigs of intact plants, root stumps and excised shoots while the potted trees were subjected to various temperature regimes in autumn, winter and spring. Osmolarity and GFS of the xylem sap (apoplast) were measured before and after cooling or warming treatments. In autumn and spring, xylem pressures of up to 160 kPa were closely correlated with soil temperature but were not correlated with GFS in xylem sap. High root pressures were associated with uptake of mineral nutrients from soil, especially nitrate. In autumn and spring, xylem pressures were detected in root stumps as well as in intact plants, but not in excised stems. In contrast, in winter, 83% of the xylem sap osmolarity in both excised stems and intact plants could be accounted for by GFS, and both GFS and osmolarity were inversely proportional to temperature. Plants kept at 1.5 degrees C developed positive xylem pressures up to 35 kPa, xylem sap osmolarities up to 260 mosmol l(-1) and GFS concentrations up to 70 g l(-1). Autumn and spring xylem pressures, which appeared to be of root origin, were about 55% of the theoretical pressures predicted by osmolarity of the xylem sap. In contrast, winter pressures appeared to be of stem origin and were only 7% of the theoretical pressures, perhaps because of a lower stem water content during winter.

Synergistic effects of lipopolysaccharides from periodontopathic bacteria on pro-inflammatory cytokine production in an ex vivo whole blood model.

Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia have been strongly associated with chronic periodontitis. This disease is characterized by an accumulation of inflammatory cells in periodontal tissue and subgingival sites. The secretion of high levels of inflammatory cytokines by those cells is believed to contribute to periodontal tissue destruction. The aim of this study was to investigate the inflammatory response of whole blood from periodontitis patients following challenges with whole cells of P. gingivalis, T. denticola, and T. forsythia or their lipopolysaccharides (LPS), individually and in combination. Whole blood collected from seven periodontitis patients was stimulated with whole cells or LPS and the production of interleukin (IL)-1beta, IL-6, IL-8, and tumor necrosis factor alpha (TNF-alpha) were quantified by enzyme-linked immunosorbent assays. The mono and mixed challenges with whole bacterial cells or LPS induced the secretion of high amounts of IL-1beta, IL-6, IL-8, and TNF-alpha by the mixed leukocyte population from periodontitis patients. In addition, P. gingivalis LPS, T. denticola LPS, and T. forsythia LPS acted in synergy to induce high levels of IL-1beta and TNF-alpha. This study suggests that P. gingivalis, T. denticola, and T. forsythia may contribute to the immunodestructive host response characteristic of periodontitis through synergistic effects of their LPS on the inflammatory response induced by a mixed population of leukocytes.

Inhibition of host extracellular matrix destructive enzyme production and activity by a high-molecular-weight cranberry fraction.

BACKGROUND AND OBJECTIVE: Periodontal diseases are a group of inflammatory disorders that are initiated by specific gram-negative bacteria and lead to connective tissue destruction. Proteolytic enzymes, including matrix metalloproteinases (MMPs) and elastase, produced by resident and inflammatory cells in response to periodontopathogens and their products, play a major role in gingival tissue destruction. The aim of this study was to investigate the effect of a high-molecular-weight fraction prepared from cranberry juice concentrate on MMP-3, MMP-9 and elastase activities, as well as on MMP production by human cells stimulated with lipopolysaccharide of Actinobacillus actinomycetemcomitans. MATERIAL AND METHODS: MMP-3 and MMP-9 production by gingival fibroblasts and macrophages treated with the cranberry fraction and then stimulated with lipopolysaccharide was measured by enzyme-linked immunosorbent assay. MMP-3, MMP-9 and elastase activities in the presence of the cranberry fraction were evaluated using colorimetric or fluorogenic substrates. The changes in expression and phosphorylation state of fibroblast intracellular signaling proteins induced by A. actinomycetemcomitans lipopolysaccharide and the cranberry fraction were characterized by antibody microarrays. RESULTS: The lipopolysaccharide-induced MMP-3 and MMP-9 responses of fibroblasts and macrophages were inhibited in a dose-dependent manner by the cranberry fraction. This fraction was found to inhibit fibroblast intracellular signaling proteins, a phenomenon that may lead to a down-regulation of activating protein-1 activity. MMP-3, MMP-9 and elastase activities were also efficiently inhibited by the cranberry fraction, even when it was used at low concentrations. CONCLUSION: These results suggest that cranberry compounds offer promising perspectives for the development of novel host-modulating strategies for an adjunctive treatment of periodontitis.

[Pathogenic potential of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia, the red bacterial complex associated with periodontitis]. / Potentiel pathogénique de Porphyromonas gingivalis, Treponema denticola et Tannerella forsythia, le complexe bactérien rouge associé à la parodontite.

Periodontitis are mixed bacterial infections leading to destruction of tooth-supporting tissues, including periodontal ligament and alveolar bone. Among over 500 bacterial species living in the oral cavity, a bacterial complex named "red complex" and made of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia has been strongly related to advanced periodontal lesions. While periodontopathogenic bacteria are the primary etiologic factor of periodontitis, tissue destruction essentially results from the host immune response to the bacterial challenge. Members of the red complex are Gram negative anaerobic bacteria expressing numerous virulence factors allowing bacteria to colonize the subgingival sites, to disturb the host defense system, to invade and destroy periodontal tissue as well as to promote the immunodestructive host response. This article reviews current knowledge of the pathogenic mechanisms of bacteria of the red complex leading to tissue and alveolar bone destruction observed during periodontitis.

Porphyromonas gingivalis-induced inflammatory mediator profile in an ex vivo human whole blood model.

Periodontitis is characterized by an accumulation of inflammatory cells in periodontal tissue and subgingival sites. Leukocytes play a major role in the host response to Porphyromonas gingivalis, a major aetiological agent of chronic periodontitis. Secretion of high levels of inflammatory mediators, including cytokines and prostaglandins, by leucocytes is believed to contribute to periodontal tissue destruction. The aim of this study was to investigate the inflammatory response of an ex vivo whole blood model to P. gingivalis stimulation. The production of interleukin-1 beta (IL-1beta), IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-13, tumour necrosis factor alpha (TNF-alpha), interferon gamma (IFN-gamma), IFN-gamma-inducible protein 10 (IP-10), monocyte chemoattractant protein-1 (MCP-1), Regulated on Activation Normal T cell Expressed and Secreted (RANTES) and prostaglandin E2 (PGE2) were quantified by enzyme-linked immunosorbent assays. P. gingivalis induced the secretion of the pro-inflammatory cytokines IL-1beta, TNF-alpha, IL-6 and IFN-gamma, the chemokines IL-8, RANTES and MCP-1 and the inflammatory mediator PGE2 in an ex vivo human whole blood model. The secretion levels were dependent on the strain and the infectious dose used. While the mediator profiles were comparable between six healthy subjects, a high interindividual variability in the levels of secreted mediators was observed. This study supports the view that P. gingivalis, by inducing high levels of inflammatory mediators from a mixed leucocyte population, can contribute to the progression of periodontitis.

Antibacterial activities of antineoplastic agents.

Fourteen antineoplastic agents were examined for in vitro antibacterial activity against 101 aerobic and anaerobic bacterial isolates representing indigenous human microflora and selected opportunistic pathogens. Only 5-fluorouracil, mitomycin, and etoposide demonstrated inhibitory effects at achievable plasma concentrations, while the remaining drugs lacked appreciable antibacterial activities.

Cryo-scanning electron microscopy observations of vessel content during transpiration in walnut petioles. Facts or artifacts?

The current controversy about the "cohesion-tension" of water ascent in plants arises from the recent cryo-scanning electron microscopy (cryo-SEM) observations of xylem vessels content by Canny and coworkers (1995). On the basis of these observations it has been claimed that vessels were emptying and refilling during active transpiration in direct contradiction to the previous theory. In this study we compared the cryo-SEM data with the standard hydraulic approach on walnut (Juglans regia) petioles. The results of the two techniques were in clear conflict and could not both be right. Cryo-SEM observations of walnut petioles frozen intact on the tree in a bath of liquid nitrogen (LN(2)) suggested that vessel cavitation was occurring and reversing itself on a diurnal basis. Up to 30% of the vessels were embolized at midday. In contrast, the percentage of loss of hydraulic conductance (PLC) of excised petiole segments remained close to 0% throughout the day. To find out which technique was erroneous we first analyzed the possibility that PLC values were rapidly returned to zero when the xylem pressures were released. We used the centrifugal force to measure the xylem conductance of petiole segments exposed to very negative pressures and established the relevance of this technique. We then analyzed the possibility that vessels were becoming partially air-filled when exposed to LN(2). Cryo-SEM observations of petiole segments frozen shortly after their xylem pressure was returned to atmospheric values agreed entirely with the PLC values. We confirmed, with water-filled capillary tubes exposed to a large centrifugal force, that it was not possible to freeze intact their content with LN(2). We concluded that partially air-filled conduits were artifacts of the cryo-SEM technique in our study. We believe that the cryo-SEM observations published recently should probably be reconsidered in the light of our results before they may be used as arguments against the cohesion-tension theory.

Simplified bioassay method for measurement of flucytosine or ketoconazole.

A simple agar-well diffusion bioassay suitable for measurement of flucytosine or ketoconazole was developed by using Candida pseudotropicalis ATCC 46764 as the assay organism. A test medium composed of (per liter) 7 g of Trypticase peptone, 7 g of YNB (yeast-nitrogen base), 15 g of glucose, and 15 g of agar was seeded with an inoculum which had been grown to no. 2 McFarland turbidity after 4 to 6 h in YNB-glucose broth. Determinations of flucytosine or ketoconazole were performed without necessity of heating or diluting of serum samples to alleviate amphotericin B interference. A linear relationship between zone diameters and log10 concentration of the drugs was observed over the pharmacologically relevant ranges of 25 to 160 micrograms/ml for flucytosine and 0.5 to 20 micrograms/ml for ketoconazole. The mean coefficient of variability for samples measured on 5 separate days was 2.4% for flucytosin and 4.0% for ketoconazole. This assay represents a significant improvement over previous bioassay methods in that a single test system may be used for measurement of either flucytosine or ketoconazole, no serum dilution or pretreatment is required, inoculum preparation is accomplished entirely on the day of the assay, and sharp, clearly defined zones of inhibition are obtained with both drugs.