Space Qualification Proceeds on the Common Data Link Program

A modular Communication, Command, and Control (C3) architecture has been developed for use in a variety of Department of Defense (DoD) applications by the Office of the Secretary of the Air Force/Defense Support Project Office (OSAF/DSPO). The C3 architecture is implemented under the direction of the SAF/DSPO\u27s Common Data Links Program Office using government defined and controlled common modules. This set of common modules is now being qualified for space applications. The family of common modules provide the building block to satisfy a wide range of unique operational requirements while achieving commonality, tri-service interoperability, multi-system connectivity, and a flexible baseline for technology insertion. SAF/DSPO has also been involved for many years in utilization studies and mission assessment analysis of small dedicated satellites as one method of providing required support to many tactical missions. This paper reviews the Common Data Links Space Qualification Program and provides an understanding of how the COL Common Modules fit into small satellite type programs of interest in satisfying tactically oriented missions. Emphasis is placed on describing the types of missions, user interactions with COL and typical C3 implementations on board the small satellites

Placental Vascular Obstructive Lesions: Risk Factor for Developing Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is a severe neonatal disease affecting particularly preterm infants. Its exact pathogenesis still remains unknown. In this study, we have compared the prevalence of vascular obstructive lesions in placentae of premature newborns which developed NEC and of a control group. We further compared separately the findings of placentae of infants of less than 30 weeks of gestation, the age group in which NEC occurs most frequently. We found signs of fetal vascular obstructive lesions in 65% of the placentae of preterm patients developing NEC, compared to only 17% of the placentae of preterm patients in the control group. In the age groups below 30 weeks of gestation, 58.5% of placentae of later NEC patients presented such lesions compared to 24.5% in the control group. The significant difference between NEC and control group suggests a strong association between fetal vascular obstructive lesions and NEC. Therefore, we propose that fetal vascular obstructive lesions might be considered as a risk factor for the development of NEC in premature infants

Messung des Sauerstoffpartialdrucks im Hirnparenchym während liquordynamischer Tests

Hintergrund und Fragestellung Entsprechend den deutschen und internationalen Leitlinien wird der dynamische Infusionstest an der Universitätsklinik Homburg routinemäßig durchgeführt, um bei Verdacht auf eine Liquorzirkulations- bzw. Resorptionsstörung die Indikation für eine Shuntimplantation zu klären. Am häufigsten wird er bei Patienten mit Verdacht auf Normaldruckhydrocephalus durchgeführt, seltener bei anderen Hydrocephalusformen oder bei idiopathischer intrakranieller Hypertension. Er wird ebenfalls bei Patienten angewandt, die bereits einen Shunt haben und bei denen eine Shunt-Dysfunktion vermutet wird. Dabei wird durch die Infusion steriler 0,9-prozentiger NaCl-Lösung in einen Seitenventrikel unter kontrollierten Bedingungen und Narkose ein Anstieg des intrakraniellen Drucks auf bis zu maximal 40 mmHg provoziert. Nach Beenden der Infusion sinkt der intrakranielle Druck wieder auf den Anfangswert. Aus dem Verlauf der Druckkurve (An- und Abstieg) lassen sich die Resistance to outflow (Rout, Maß für den Abflusswiderstand) und der Pressure-Volume-Index (PVI, Maß für die Reserveräume) in ihrer Abhängigkeit vom Druck berechnen. Die im 19.Jahrhundert in der aktuellen Form formulierte Monro-Kellie-Doktrin, auch Monro-Kellie-Hypothese genannt, besagt, dass die Summe der Volumen von Hirngewebe, Blut und Liquor innerhalb der Schädelhöhle gleich bleiben muss, um den intrakraniellen Druck konstant zu halten. Während des dynamischen Infusionstests wird das Liquorvolumen durch die intraventrikuläre Infusion von NaCl-Lösung erhöht. Da Hirngewebe kaum kompressibel ist, muss dies durch eine Reduktion des Volumens von Liquor (z.B. Ausweichen nach spinal) oder Blut kompensiert werden. Letzteres kann zum einen durch den vermehrten Abfluss venösen Blutes geschehen, zum anderen aber auch durch verminderte Zufuhr im arteriellen System. Die vorliegende Arbeit untersucht erstmalig, ob und wie sich gegebenenfalls der durch den dynamischen Infusionstest hervorgerufene Druckanstieg auf den zerebralen Sauerstoffpartialdruck auswirkt. Insbesondere soll erkannt werden, ob es Patienten gibt, bei denen der zerebrale Sauerstoffpartialdruck während des dynamischen Infusionstests abfällt, und wenn ja, welche Charakteristika diese Patienten aufweisen. Auf diese Weise sollen die Patienten in Zukunft besser vor Hirnischämien geschützt werden können, indem etwa die Infusion früher gestoppt wird. Methode Zwischen März 2009 und August 2010 wurden an der Klinik für Neurochirurgie der Universitätsklinik Homburg bei 34 entsprechend aufgeklärten Patienten während eines dynamischen Infusionstests der Sauerstoffpartialdruck sowie der Druck und die Temperatur im Hirnparenchym mithilfe einer „Neurovent PTO“ –Sonde der Firma Raumedic gemessen. Die Daten wurden retrospektiv ausgewertet. Ergebnisse 1. Absolute Werte des intraparenchymatösen Sauerstoffpartialdrucks Die erhobenen Ruhewerte des intraparenchymatösen Sauerstoffpartialdrucks lagen in vielen Fällen deutlich niedriger als bisher in anderen Studien beschrieben; dies gilt insbesondere für Patienten mit Hydrocephalus. Zudem zeigen die vorliegenden Daten, dass der Sauerstoffpartialdruck durch das verwendete Anästhetikum beeinflusst wird. 2. Änderungen des intraparenchymatösen Sauerstoffpartialdrucks (PtiO2) während des Infusionstests Es wurden die folgenden drei Muster identifiziert: Muster A: Es kommt initial zu einem Abfall des PtiO2, gefolgt von einem Anstieg. Dies ist bei 11 Patienten der Fall. Muster B: Der PtiO2 steigt während der gesamten Messdauer. Dies ist bei 13 Patienten der Fall. Muster C: Der PtiO2 sinkt während der gesamten Messdauer. Dies ist bei 3 Patienten der Fall. Insgesamt liegt der PtiO2 bei 24 von 27 Patienten (88,9%) am Ende des Infusionstests höher als am Anfang. Sowohl die Temperatur als auch der intraparenchymatöse Druck korrelieren bei fast allen Patienten signifikant mit dem PtiO2, wobei die Richtung der Korrelation je nach Patient unterschiedlich ist. Patienten mit positiver bzw. negativer Korrelation unterscheiden sich durch die Hauptdiagnose und das Vorhandensein kardiovaskulärer Risikofaktoren. 3. Temperatur Die intraparenchymatöse Temperatur nahm während des Infusionstests bei allen Patienten ab. Der Temperaturabfall betrug zwischen 0,11 und 4,45 Grad Celcius, im Durchschnitt 1,01 ± 0,97 Grad Celcius. Diskussion a. Absolute Werte Die Tatsache, dass die hier gemessenen absoluten Werte des Sauerstoffpartialdrucks insbesondere bei Patienten mit Hydrocephalus deutlich niedriger sind als bisher beschrieben, unterstützt die von mehreren Autoren formulierte Hypothese einer chronischen Hirnischämie bei Patienten mit Hydrocephalus. Die Ergebnisse deuten ebenfalls darauf hin, dass die Normwerte für den Sauerstoffpartialdruck im gesunden Hirn bisher überschätzt wurden. Da die meisten Studien an Patienten mit Traumata durchgeführt wurden, ist es denkbar, dass die Werte infolge überschießender Vasodilatation erhöht waren, und dass der Sauerstoffpartialdruck im gesunden Hirn deutlich niedriger ist als bisher angenommen. b. Änderungen des intraparenchymatösen Sauerstoffpartialdrucks während des Infusionstests Bei 88,9% der Patienten ist der zerebrale Sauerstoffpartialdruck am Ende des Infusionstests höher als davor. Eine mögliche Erklärung hierfür ist eine reaktive (überschießende) Vasodilatation oder eine Art Luxusperfusion, also eine paradoxe Steigerung der Durchblutung bei vermindertem Stoffwechsel, wie sie zum Beispiel nach ischämischen Insulten zu beobachten ist. Möglicherweise liegt der Unterschied zwischen den Patienten, die mit einem Abfall des PtiO2 reagieren (Gruppe C) und denen, die mit einem Anstieg des PtiO2 reagieren (Gruppe A und B), in der mehr oder weniger bestehenden Intaktheit der Autoregulationsmechanismen. Dies würde zu dem Ergebnis passen, dass die Patienten mit negativer Korrelation zwischen Pti und PtiO2, d.h. bei denen der PtiO2 bei steigendem Druck abnimmt, überwiegend (67%) keine kardiovaskulären Risikofaktoren aufweisen. Umgekehrt handelt es sich bei den Patienten mit positiver Korrelation zwischen Pti und PtiO2 überwiegend (58%) um solche mit kardiovaskulären Risikofaktoren. c. Temperatur Die vorliegende Untersuchung zeigt, dass eine Senkung der Temperatur im Hirnparenchym durch Infusion von NaCl-Lösung mit einer Temperatur von 20°C in das Ventrikelsystem erreicht wird: In der vorliegenden Untersuchung nimmt die intraparenchymatöse Temperatur während des Infusionstests bei sämtlichen Patienten ab. Dies stellt neue therapeutische Möglichkeiten in Aussicht, um den neuroprotektiven Effekt einer lokalen Hypothermie zu nutzen, ohne die Komplikationen einer systemischen Hypothermie zu haben. Schlussfolgerung Diese Untersuchung zeigt, dass der zerebrale Sauerstoffpartialdruck bei allen Patienten durch den Infusionstest beeinflusst wird. Es gibt jedoch kein einheitliches Reaktionsmuster. Die Art und Weise, wie sich der zerebrale Sauerstoffpartialdruck eines Patienten während des Infusionstests ändert, hängt von verschiedenen Faktoren ab. In dieser Untersuchung wird gezeigt, dass die Ventrikelgröße, die Temperaturänderung, die Grunderkrankung und das Vorhandensein kardiovaskulärer Risikofaktoren von Bedeutung sind. Das Monitoring des zerebralen Sauerstoffpartialdrucks wird heute bereits bei anderen Pathologien eingesetzt und es wurde gezeigt, dass es z.B. dazu beitragen kann, das Outcome nach Schädel-Hirn-Trauma zu verbessern. Im Rahmen des Infusionstests kann das routinemäßige Monitoring des PtiO2 sicherstellen, dass durch die Druckerhöhung keine Hirnischämie hervorgerufen wird und somit die Prozedur für die Patienten sicherer machen, zum Beispiel indem die Infusion bei Abfall des PtiO2 frühzeitig abgebrochen wird. Dies ist in einer weiteren prospektiven multizentrischen Studie anzudenken. Zudem kann das Monitoring zu einem besseren Verständnis der Zusammenhänge zwischen erhöhtem ICP und Hirnischämie sowie der Autoregulationsmechanismen bei Patienten mit Hydrocephalus oder Idiopathischer Intrakranieller Hypertension beitragen.Introduction In accordance with German and International Guidelines, Dynamic Infusion Tests are performed routinely at the University Hospital of Homburg in order to determine if there is an indication for shunt surgery. Infusion tests are performed on patients suspected of having impaired reabsorption or circulation of cerebrospinal fluid (CSF), i.e. mostly patients suspected of having Normal Pressure Hydrocephalus (NPH), but also other forms of hydrocephalus or Idiopathic Intracranial Hypertension (IIH). It is also used on patients who already have a shunt, when a malfunction of a shunt is suspected. During the test, sterile 0.9% NaCl-solution is administered at a constant rate of 3 ml/min into a side ventricle of an anesthetized patient. This leads to an increase of the Intracranial Pressure (ICP) up to a maximum of 40 mmHg. After the infusion is stopped, the ICP drops back to the initial pressure level. The rise and descent of the pressure curve allow the calculation of the Resistance to outflow (Rout) and the Pressure-Volume-Index (PVI) at different pressure levels. The Monro-Kellie-Hypothesis, which was expressed in its current form in the 19th century, indicates that the sum of the volumes of the brain tissue, blood and CSF inside the skull must stay constant in order to keep the ICP stable. During the infusion test, the infusion of isotonic solution leads to an increase in CSF volume. Since brain tissue can hardly be compressed, the increase in CSF volume has to be compensated by a decrease in the volume of either CSF (into the spinal canal) or blood. The latter can either be achieved through an increased outflow of venous blood or through a reduced inflow of arterial blood. This work examines for the first time if and how the pressure rise induced by the dynamic infusion test influences the oxygen partial pressure in the brain tissue (PtiO2). In particular we wanted to determine if it leads to a decrease in brain tissue oxygen in some patients and if so, identify the characteristics of those patients in order to protect them better in future. Summary 10 Method Between March 2009 and August 2010, 34 patients who were meant to undergo an infusion test gave their informed consent to a simultaneous measurement of brain tissue oxygen through a second probe inserted into the brain tissue. The data were analysed retrospectively. Results 1. Absolute values of the brain tissue oxygen In the present study, the absolute PtiO2 values were considerably lower than in studies published so far, especially in patients with hydrocephalus. The data also show that the oxygen concentration is influenced by the anesthetic agent used. 2. Changes of brain tissue oxygen during the infusion test Three patterns were identified : Pattern A : initially, there is an increase in PtiO2, followed by a decrease. This is the case in 11 patients. Pattern B : the PtiO2 increases during the entire duration of the infusion test. This is the case in 13 patients Pattern C : the PtiO2 decreases during the entire duration of the infusion test. This is the case in 3 patients. Altogether, in 24 of 27 patients (88.9%), the PtiO2 level is higher at the end of the infusion test compared to the level at the start. Both brain temperature and brain pressure correlate significantly with the PtiO2 in almost all patients, although there are differences in the direction of the correlation. Patients with positive and negative correlation differ through their main diagnosis and the occurrence of cardiovascular risk factors. 3. Temperature The brain temperature decreased during the infusion test in 100% of the patients. The temperature decrease was between 0.11 and 4.45 °C, on average 1.01 ± 0.97 °C. Summary 11 Discussion a. Absolute values The fact that the measured values of PtiO2, in particular those of patients with hydrocephalus, lie notably under the values published so far by other authors supports the hypothesis of chronic brain ischemia in patients with hydrocephalus. The results also suggest that current standard values have been overestimated. Since most studies on brain tissue oxygen levels have been conducted on patients suffering from head trauma, it is possible that oxygen levels were increased due to reactive vasodilation, and hence that normal values are significantly lower in healthy persons. b. Evolution of PtiO2 during the infusion test In 88.9% of the patients, the level of PtiO2 is higher at the end of the test than at its beginning. A possible explanation for this is a reactive and excessive vasodilation similar to the luxury perfusion seen in acute stroke, i.e. a paradox increase of blood circulation despite decreased metabolism. The difference between the patients who react with an increase of PtiO2 and those who react with a decrease possibly lies in the more or less functioning autoregulation mechanisms. This would match the fact that a majority (67%) of patients where the correlation between Pti and PtiO2 was negative, i.e. where the PtiO2 decreased while the Pti increased, didn’t show any cardiovascular risk factors. Reciprocally, most people (58%) of the patients with a positive correlation between Pti and PtiO2 were presenting cardiovascular risk factors. c. Temperature This study shows that a decrease in brain temperature can be achieved through infusion of NaCl solution with a temperature of 20 °C in the brain ventricles. In the present study the temperature decreased in 100% of the patients. This might lead to new therapeutic possibilities, taking advantage of the neuroprotective effect of local hypothermia without the complications of generalized hypothermia. Conclusion This study shows that the infusion test influences PtiO2 in every patient. However, there is no consistent pattern as the way in which a patient’s PtiO2 reacts to the infusion test depends on Summary 12 many different factors. This study shows that the ventricle size, the temperature change, the main diagnosis and the presence or absence of cardiovascular risk factors play a role. The monitoring of PtiO2 is already routinely used in other pathologies and it has been shown that it can, for example, improve the outcome after severe head injury. If done during the infusion test, it could help make the procedure safer for the patient by preventing brain ischemia, i.e. through earlier stopping of the infusion. This should be investigated in a prospective multicentre study. Furthermore, monitoring PtiO2 can help to better understand the interactions between raised ICP and brain ischemia as well as autoregulation mechanisms in patients with hydrocephalus or IIH

Performances physiologiques et forces d'attachement des moules triploïdes

RÉSUMÉ : La mytiliculture est une ressource économique importante pour le Canada, avec par exemple, une production de 26 000 tonnes en 2019 pour une valeur de plus de 43 millions de dollars. Cependant, une cause majeure de perte de production pour les mytiliculteurs provient du détachement des moules au cours de leur croissance. Ce phénomène est particulièrement important durant la saison de reproduction. En effet, les moules investissent la majeure partie de leur énergie dans la reproduction et ont donc moins d'énergie pour la byssogenèse. Cela conduit à un affaiblissement du byssus, qui peut ultimement mener au détachement des moules. De tels détachements peuvent considérablement réduire la productivité des mytilicultures et résulter en la perte de plus de 50% de la production. Récemment, il y a eu un intérêt croissant pour le développement des écloseries de moules et plus spécifiquement pour la production de moules triploïdes. En effet, il est connu que la triploïdie tend à réduire la fertilité des bivalves et peut même produire des bivalves entièrement stériles qui ont plus d'énergie à investir dans leur croissance et d'autres tissus vitaux (par exemple le byssus). L'objectif principal de cette thèse de doctorat était donc de valider les effets de la triploïdie chez Mytilus edulis, notamment concernant ses capacités de reproduction et d'attachement, ainsi que les potentiels impacts sur la physiologie et le métabolisme des moules. De plus, le développement de techniques de production de moules triploïdes dans des conditions d'écloserie était aussi un aspect important de ce projet. Le premier objectif de cette thèse consistait à développer des techniques efficaces d'induction de la triploïdie, applicables dans des conditions d'écloserie par un personnel non spécialisé. Afin d'induire la triploïdie, il a été décidé d'inhiber l'extrusion du second globule polaire d'œufs fécondés. Des traitements à chaud ou à froid ont été appliqués, ainsi que des traitements chimiques en utilisant de la 6-(Dimethylamino)purine (6-DMAP). De plus, l'efficacité des traitements a été comparée en fonction de leur moment d'application (post-fécondation). Les résultats ont montré que le traitement des œufs à 17 minutes post-fécondation avec 400 µM de 6-DMAP, a induit les plus forts taux de triploïdie avec plus de 90% d'induction. De plus, les larves triploïdes ont montré un avantage de croissance significatif jusqu'à la fin de l'étude, au moment de leur fixation. Le second objectif de cette thèse portait sur l'étude de la production et les propriétés mécaniques des fibres de byssus, chez des moules Mytilus edulis de petite taille ( 50 mm). Les résultats n'ont pas montré d'investissement reproductif important chez les moules 50 mm ont montré une réduction de l'investissement de reproduction chez les triploïdes, ainsi qu'une maturation incomplète des gamètes, des signes de résorption des gamètes et un sexe-ratio fortement altéré avec une absence de femelles. Le quatrième objectif était de comparer la production, les propriétés mécaniques, ainsi que la composition du byssus de moules de taille commercialisable (> 50 mm). La production de byssus et les analyses des propriétés mécaniques ont été faites selon la même méthodologie que pour le 2ème objectif. La composition en acides aminés et métaux des fibres a également été analysée. Les résultats ont montré des tendances similaires chez les moules > 50 mm avec les résultats présentés en lien avec le deuxième objectif. La composition et la structure en acides aminés des fibres n'étaient pas significativement différentes entre les 2 groupes. Cependant, certains métaux, tels que le B, Cu, SR, Os, W, Ag, Nb, Bi, et Tl étaient en concentration plus importante dans le byssus des moules diploïdes. Les moules triploïdes ont montré une augmentation du taux de filtration, du potentiel de croissance, ainsi que de la résistance de la coquille de respectivement 48%, 57%, 40%. Ensemble, les résultats de cette étude montrent un fort potentiel des moules triploïdes pour l'aquaculture, avec une croissance augmentée, la production de plus de fibres de byssus ayant des propriétés mécaniques supérieures, mais également moins d'investissement en reproduction et potentiellement plus d'énergie disponible pour d'autres activités métaboliques. Ainsi, la production de moules triploïdes pourrait réduire les pertes dues au détachement et augmenter les taux de production grâce à une croissance supérieure et une meilleure survie. -- Mot(s) clé(s) en français : Triploïdie, Byssus, Mytilus edulis, Bivalve, Attachement, Reproduction, Filtration, Potentiel de croissance, Croissance. -- ABSTRAT : Mussel farming is an important economic resource for Canada accounting for a production of 26,000 tonnes produced in 2019 and a value over＄43 million. A major cause of loss of production for mussel farmers originates from the fall-off of mussels during their growth. This phenomenon is particularly important during the reproductive season since mussels invest most of their energy in reproduction and therefore have less energy available for byssogenesis. This leads to a weakening of the byssus, which can ultimately result in the fall-off of the mussels. This can considerably reduce the productivity of mussel farms and result in the loss of more than 50% of production. Recently there has been a growing interest in the development of mussel hatcheries and more specifically in the production of triploid mussels. Indeed, it is known that triploidy tends to reduce the fertility of bivalves and can even produce sterile bivalves which would have more energy to invest in their growth and in other vital tissues (i.e. the byssus). The main objective of this doctoral thesis was therefore to validate the effects of triploidy in Mytilus edulis, in particular regarding its reproductive and attachment performances, as well as the potential impacts on its physiology and metabolism of mussels. In addition, the development of techniques to produce triploid mussels under hatchery conditions was also an important aspect of this project. The first objective of this thesis consisted in developing effective triploidy induction techniques applicable in hatchery conditions by non-specialized personnel. To induce triploidy, it was decided to inhibit the extrusion of the second polar body of fertilized eggs. Hot or cold treatments were applied, as well as chemical treatments using 6-(Dimethylamino)purine (6-DMAP). In addition, the efficiency of the treatments was compared according to their time of application (post-fertilization). The results showed that the treatment of eggs at 17 minutes post-fertilization with 400 µM of 6-DMAP induced the highest levels of triploidy with more than 90% induction. Additionally, triploid larvae showed a significant growth advantage until the end of the study when larvae settled. The second objective of this thesis focused on the production and mechanical properties of byssus threads in small Mytilus edulis mussels (˂ 30 mm), before their first investments in reproduction. Byssus production was stimulated by placing the mussels in a hydrodynamic flume for 3 days. At the end of the 3 days, the threads were counted, collected, tensiometric analyzes were applied to each thread. The results showed that although the mussels did not yet invest massive energy in reproduction, the triploids produced significantly more threads (65%) than the diploids, with altered mechanical properties and in particular an increase in Young's modulus of 45% in triploids. In addition, the clearance rate and scope for growth were respectively 40% and 260% higher in triploids compared to diploids. The third objective aimed to compare the reproductive performance of diploid and triploid mussels of two different size groups (˂ 30 mm and ˃ 50 mm). The results did not show significant reproductive investment in mussels ˂ 30 mm, nor any difference between diploids and triploids for this size group. On the other hand, mussels ˃ 50 mm showed a reduction in reproductive investment in triploids, as well as an incomplete maturation of gametes, signs of gamete resorption and a strongly altered sex ratio with an absence of females. The fourth objective compared the production, the mechanical properties, as well as the composition of the byssus of commercial size mussels ˃ 50 mm. The byssal production and the analyzes of the mechanical properties were made according to the same methodology as for the 2nd chapter. The amino acid and metal composition of the fibers were also analyzed. The results showed similar trends in mussels ˃ 50 mm with the results of the 2nd chapter. The structure and composition in amino acids of the byssal threads were not significantly different between the 2 groups. However, some metals, such as B, Cu, SR, Os, W, Ag, Nb, Bi, Tl were in higher concentration in the byssus of diploid mussels. The triploid mussels showed an increase in filtration rate, growth potential, as well as shell strength by 48%, 57%, 40% respectively. Together, the results of this study show a strong potential of triploid mussels for aquaculture, with increased growth, production of more byssal threads with superior mechanical properties, but also less investment in reproduction and potentially more energy available for other metabolic activities. Thus, the production of triploid mussels could reduce losses due to fall-off and increase the production rates through superior growth and better survival. -- Mot(s) clé(s) en anglais : Triploidy, Byssus, Mytilus edulis, Bivalve, Attachment, Reproduction, Clearance rate, Scope for growth, Growth

Malignancy transformation of chronic osteomyelitis: description of 6 cases of Marjolin's ulcers

Background: Marjolin's ulcer describes any malignant transformation of a chronic inflammatory lesion. In the majority of cases, a squamous cell carcinoma is diagnosed. Malignant transformation occurs usually after a long period of latency of chronic infection; it takes approximately 35years on average. There are no typical clinical presentations, but several indirect signs may suggest the malignant transformation, such as increased or changed discharge, pathologic fracture, a slow-growing exophytic mass, or other suggestive signs of malignant transformation, which should prompt to biopsy for histological exam. The diagnosis of chronic osteomyelitis should not prevent to search for carcinoma. Case description: We present six patients with chronic osteomyelitis that developed well-differentiated squamous cell carcinoma. All patients were older than 50years (mean 60years, range 52-77years). Five Marjolin's ulcers were located on the lower limb and one on the arm. The average time of the chronic discharging osteomyelitis before diagnosis of carcinoma ranged between 12 and 40years. All patients were treated by amputation of the affected limb. None had metastasis, and one patient developed local recurrence and received palliative treatment. Clinical relevance: Our study emphasizes that Marjolin's ulcer should be considered as a rare but significant long-term complication of chronic osteomyelitis. The finding of microorganisms should not prevent from further diagnostic procedures by histopathological examination so that the correct surgical treatment can be performe

Combination of Immunohistochemistry and Ploidy Analysis to Assist Histopathological Diagnosis of Molar Diseases

Background Differential diagnosis between hydropic abortion, partial mole and complete mole is still a challenge for pathologists but really important for patient management. Material and Method In this study, we have evaluated 111 products of conception from the first trimester. Histological analysis was made according to the main diagnostic histopathological features described in the literature and the cases were categorized in hydropic abortus (HA), partial mole (PM) and complete mole (CM). Immunohistochemistry was performed using monoclonal antibody against p57 kip protein a putative paternally imprinted inhibitor gene and DNA ploidy was analysed in all cases by image cytometry. Results All 23 HAs presented a diploid DNA content and were p57 kip2 positive. From the 28 CMs, 12 cases (43%) were diploid and 16 cases (57%) were tetraploid but no expression of p57 kip2 was found with positive internal controls. From the 60 PMs, 58 cases were positive for p57 kip2 expression and 53 cases (88%) were triploid, 6 cases (10%) tetraploid and 1 case (2%) diploid. Conclusion This study on 111 cases of early pregnancies confirms the usefulness of immunohistochemistry and cytometry but demonstrates the importance of the combination of both techniques to assist histology for the best reliable diagnosis

Effets des nanoparticules d'argents sur les composés organiques soufrés d'origine biologique

RÉSUMÉ: Il est connu que l’argent ionique ainsi que les nanoparticules d’argent (AgNPs) ont une forte affinité pour les composés soufrés aussi bien inorganiques qu’organiques. De nombreuses études ont en effet démontré des interactions entre les AgNPs et des acides aminés soufrés tels que la cystéine via le groupement thiol de la molécule. De plus, certaines recherches ont proposé que les AgNPs puissent se lier aux protéines via leurs groupements thiols. L’objectif principal de ce mémoire était d’analyser les interactions des AgNPs avec les composés soufrés organiques tels que la cystéine et l’albumine et de comparer les résultats obtenus avec les effets des ions Ag+ sur ces mêmes molécules. Par ailleurs il s’est présenté une occasion de rédiger une revue de littérature afin d’expliquer le comportement, les transformations et le devenir des AgNPs une fois introduites dans l’environnement aquatique ; cette revue fait partie de ce mémoire. Suite à des expériences de spectroscopie RAMAN et de matrices d’excitation-émission de fluorescence, des interactions entre l’argent ionique avec le soufre du groupement thiol de la cystéine ont été démontrées. De plus, les effets des ions Ag+ et des AgNPs sur la protéine d’albumine ont été mesurés. Les résultats obtenus ont montré des effets plus importants en présence des ions Ag+ que des AgNPs. Il a été proposé que les ions argent, étant plus petits que les AgNPs, aient un accès facilité à certains sites de liaisons sur la protéine d’albumine en comparaison des nanoparticules. Finalement, il a été indirectement observé que bien que les AgNPs aient des effets plus faibles que l’argent ionique sur l’albumine, elles sont tout de même capables d’affecter directement la protéine. À notre connaissance, aucune étude antérieure n’avait comparé les effets des ions argent à ceux des nanoparticules d’argent sur la protéine d’albumine. -- Mot(s) clé(s) en français : AgNPs, ROS, soufre, albumine, fluorescence, RAMAN, environnement. -- ABSTRACT: It is well known that silver ions as well as silver nanoparticles (AgNPs) have a high affinity for organic and inorganic sulfur compounds. Indeed, many studies have demonstrated the interactions between AgNPs and small amino acids such as cysteine through the thiol group of the molecules. Moreover, some studies suggested that AgNPs could bind to proteins through their thiol groups. The main objectives of this study were to analyse the interactions of AgNPs with sulfur organic compounds such as cysteine and albumin as well as to compare the obtained results with the effect of silver ions on these same organic compounds. Furthermore, there was an opportunity to produce a literature review on the behavior, transformations and future of AgNPs once in the aquatic environment. This review takes part in this document. Experiments using RAMAN spectroscopy and excitation-emission fluorescence matrix have demonstrated interactions between ionic silver and sulfur of the thiol group of cysteine. Also, effects of Ag+ ions and AgNPs on the protein of albumin have been measured. Results showed that the effects were enhanced in presence of silver ions compared with AgNPs. It was suggested that as silver ions are smaller than AgNPs, they may have promoted access for specific binding sites of albumin compared to the nanoparticles. Finally, it has been indirectly observed that although AgNPs had less impact on albumin than the silver ions, they are still able to directly affect the protein. To our knowledge, no previous study had compared the effects of silver ions and AgNPs on the protein of albumin. -- Mot(s) clé(s) en anglais : AgNPs, ROS, sulfur, albumin, fluorescence, RAMAN, environment

Examen anatomo-pathologique du placenta: ses indications, ses lésions chez la femme drépanocytaire

Dans cet article, les auteurs rappellent les principales indications de l'examen anatomopathologique du placenta. Ils essaient d'élucider, au vue de la littérature l'atteinte placentaire en cas de drépanocytose, marquée par le faible poids, les infarctus,la sclérose des villosités, la présence des érythrocytes en faucilles et des dépôts de fibrines dans l'espace intervilleux. Mots cles: pathologie, placenta, drépanocytose Clinics in Mother and Child Health Vol. 1(1) 2004: 9-1

Hirschsprung's disease: the "Swiss roll” technique revisited

Purpose: During pull-through for Hirschsprung's disease (HSCR), the assessment of innervation is mainly based on the presence of ganglion cells when conventional Hematoxylin and Eosin (HE) staining is used. In hypoganglionosis, the evaluation is difficult. We adapted a standardized methodology for the examination of resected bowel after HSCR surgery, using the technique described by Moolenbeek on rodent intestine and later by Meier-Ruge in children. We have analysed the entire innervation of surgically resected bowels and compared the results with the follow up of patients. Methods: Three longitudinal strips of colon were harvested from the mesenteric, anti-mesenteric and intermediate part in the whole length of resected colon of six patients with HSCR. Each strip was divided into two parts. One of the contiguous strips was assessed with HE and Hematoxylin-Phloxin-Safran, and the other one with acetylcholinesterase (AChE) histochemistry. We analyzed the distribution of ganglion cells and nerve arrangement along the strips with both techniques and compared the results obtained in the three different regions of the bowel. Results: There was no significant difference in the pattern of innervation circumferentially. There was a correlation between a progressive increase of AChE activity and nerve hypertrophy and a decrease of ganglion cells from the proximal to the distal part of the resected colon in the submucosa and the myenteric plexus. Nerve hypertrophy and AChE-positive reaction in the mucosa were found at the resection border in patients who presented postoperative complications. Conclusions: Simultaneous assessment of nerve cells, nerve fibers and AChE activity is important in the evaluation of the innervation of the bowel segment proximal to the aganglionic zone. The method described is feasible and can be adapted to older children and adults with larger bowels. These results point out the importance of assessing nerve fibers in intraoperative biopsies during pull-through procedures to prevent uncomplete surgical bowel resectio