Search

The aim of this study is to deliver genes in Achilles tendons using ultrasound and microbubbles. The rationale is to combine ultrasound-assisted delivery and the stimulation of protein expression induced by US. We found that mice tendons injected with 10 μg of plasmid encoding luciferase gene in the presence of 5×10⁵ BR14 microbubbles, exposed to US at 1 MHz, 200 kPa, 40% duty cycle for 10 min were efficiently transfected without toxicity. The rate of luciferase expression was 100-fold higher than that obtained when plasmid alone was injected. Remarkably, the luciferase transgene was stably expressed for up to 108 days. DNA extracted from these sonoporated tendons was efficient in transforming competent E. coli bacteria, indicating that persistent intact pDNA was responsible for this long lasting gene expression. We used this approach to restore expression of the fibromodulin gene in fibromodulin KO mice. A significant fibromodulin expression was detected by quantitative PCR one week post-injection. Interestingly, ultrastructural analysis of these tendons revealed that collagen fibrils diameter distribution and circularity were similar to that of wild type mice. Our results suggest that this gene delivery method is promising for clinical applications aimed at modulating healing or restoring a degenerative tendon while offering great promise for gene therapy due its safety compared to viral methods., (Copyright © 2011 Elsevier B.V. All rights reserved.)

This work is a follow-up of our previous paper (Heinlaan et al., 2008. Chemosphere 71, 1308-1316) where we showed about 50-fold higher acute toxicity of CuO nanoparticles (NPs) compared to bulk CuO to water flea Daphnia magna. In the current work transmission electron microscopy (TEM) was used to determine potential time-dependent changes in D. magna midgut epithelium ultrastructure upon exposure to CuO NPs compared to bulk CuO at their 48 h EC(50) levels: 4.0 and 175 mg CuO/L, respectively. Special attention was on potential internalization of CuO NPs by midgut epithelial cells. Ingestion of both CuO formulations by daphnids was evident already after 10 min of exposure. In the midgut lumen CuO NPs were dispersed whereas bulk CuO was clumped. By the 48th hour of exposure to CuO NPs (but not to equitoxic concentrations of bulk CuO) the following ultrastructural changes in midgut epithelium of daphnids were observed: protrusion of epithelial cells into the midgut lumen, presence of CuO NPs in circular structures analogous to membrane vesicles from holocrine secretion in the midgut lumen. Implicit internalization of CuO NPs via D. magna midgut epithelial cells was not evident however CuO NPs were no longer contained within the peritrophic membrane but located between the midgut epithelium microvilli. Interestingly, upon exposure to CuO NPs bacterial colonization of the midgut occurred. Ultrastructural changes in the midgut of D. magna upon exposure to CuO NPs but not to bulk CuO refer to its nanosize-related adverse effects. Time-dependent solubilisation of CuO NPs and bulk CuO in the test medium was quantified by recombinant Cu-sensor bacteria: by the 48th hour of exposure to bulk CuO, the concentration of solubilised copper ions was 0.05 ± 0.01 mg Cu/L that was comparable to the acute EC(50) value of Cu-ions to D. magna (48 h CuSO(4) EC(50) = 0.07 ± 0.01 mg Cu/L). However, in case of CuO NPs, the solubilised Cu-ions 0.01 ± 0.001 mg Cu/L, explained only part of the toxicity., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Object: The dura mater has 2 dural layers: the endosteal layer (outer layer), which is firmly attached to the bone, and the meningeal layer (inner layer), which directly covers the brain. These 2 dural layers join together in the middle temporal fossa or the convexity and separate into the orbital, lateral sellar compartment (LSC), or spinal epidural space to form the extradural neural axis compartment (EDNAC). The aim of this work was to anatomically verify the concept of the EDNAC by using electron microscopy., Methods: The authors studied the cadaveric heads obtained from 13 adults. Ten of the specimens (or 20 perisellar areas) were injected with colored latex and fixed in formalin. They carefully removed each brain to allow a superior approach to the perisellar area. The 3 other specimens were studied by microscopic and ultrastructural methods to describe the EDNAC in the perisellar area. Special attention was paid to the dural layers surrounding the perisellar area. The authors studied the anatomy of the meningeal architecture of the LSC, the petroclival venous confluence, the orbit, and the trigeminal cave. After dissection, the authors took photographs of the dural layers with the aid of optical magnification. The 3 remaining heads, obtained from fresh cadavers, were prepared for electron microscopic study., Results: The EDNAC is limited by the endosteal layer and the meningeal layer and contains fat and/or venous blood. The endosteal layer and meningeal layer were not identical on electron microscopy; this finding can be readily related to the histology of the meninges., Conclusions: In this study, the authors demonstrated the existence of the EDNAC concept in the perisellar area by using dissected cadaveric heads and verified the reality of the concept of the meningeal layer with electron microscopy. These findings clearly demonstrated the existence of the EDNAC, a notion that has generally been accepted but never demonstrated microscopically.

Acquired cutis laxa is an uncommon disorder sometimes associated with monoclonal gammopathy and multiple myeloma, although the mechanism of this link is unclear. We report here a case of a 34-year-old man with generalized acquired cutis laxa and monoclonal light chain disease with renal and neurological involvement. Electron microscopy examination of a skin sample revealed shortened and fragmented elastic fibres in the reticular dermis and normal collagen bundles. Immunogold labelling revealed anti-lambda antibodies closely bound to the microfibrillar component of elastic fibres, thus supporting a causal relationship between monoclonal gammopathy and the changes in skin elasticity.

We found that 60-min glucose deprivation leads to progressive decrease in the mitochondrial membrane potential and increase in [Ca(2+)](i) in cultured cerebellar granule neurons. The latter effect was fully reversible, returning to the basal level 60 min after restoration of normal glucose level in the incubation medium, whereas mitochondrial membrane potential remained at 10.0+/-1.8% below the initial value. Electron microscopy indicated that glucose deprivation induced appearance of mitochondria with local lightening of the matrix and destruction of cristae. This mitochondrial conformation was preserved during the restoration phase after glucose level in the cultivation medium returned to the normal level. Neuronal death within a 24-h period after 60-min glucose deprivation was relatively small, being 14.0+/-4.4%.

Mutual interactions between human breast cancer cells and endothelial cells were studied in a model mimicking tumor cell intravasation. MDA-MB-231 tumor cells and human umbilical vein endothelial cells (HUVEC) were cocultured on opposite sides of a Transwell filter allowing tumor cell contacts with the basement membrane of the HUVEC forming endothelium and tumor cell transendothelial migration. Confocal microscopy analysis showed that transmigrating MDA-MB-231 cells lay under the HUVEC, thereby inducing HUVEC detachment and tumor cell-HUVEC contact-dependent apoptosis. GM6001 a matrix metalloproteinase (MMP) inhibitor inhibited almost completely, the MDA-MB-231 cell transendothelial migration and the anoikis process. In this intravasation model, a tumor cell invasive mechanism was demonstrated (i) induction of extensive endothelial anoikis induced by degradation of the extracellular matrix (ECM) components, (ii) activation of pro-matrix metalloproteinase (MMP)-2 into MMP-2 by the MT1-MMP-TIMP (tissue inhibitor metalloproteinase) 2-pro-MMP-2 membrane complex and (iii) attraction and migration of metastatic cell through apoptotic endothelium. These interactions could partly explain the necrosis-angiogenesis relationship in tumor angiogenesis.

Aim: To evaluate very-high-frequency (VHF) ultrasound imaging as a new method to detect and quantify early corneal epithelium changes induced by chronic exposure to a benzalkonium-chloride-containing antiglaucoma drug., Methods: Timolol preserved with 0.01% benzalkonium chloride solution was applied b.i.d. in 1 eye of 10 rabbits for 56 days. Unpreserved timolol solution was used as control. Ocular surface changes were assessed weekly combining clinical examinations, in vivo 60-MHz ultrasound imaging and ex vivo histological analysis., Results: VHF ultrasound imaging allowed quantitative measurement of corneal epithelium thickness and qualitative imaging of toxic epithelial damage. It revealed significantly decreased epithelial thickness in vivo as early as the 21st day of treatment (40.75 +/- 1.72 microm at D0 vs. 39 +/- 2 at D21, vs. 31.9 +/- 2.98 at D56; p = 0.017 and p = 0.005, respectively). The first clinical changes appeared from the 42nd day of treatment (conjunctival redness, conjunctival staining and corneal staining; D56 compared to D0: p = 0.005, 0.01 and 0.004, respectively) and then correlated with VHF ultrasound data. Epithelial thickness measured with VHF ultrasound was correlated with histological epithelial pachymetry (p < 0.001) and with the corneal damage score assessed with scanning electron microscopy (p = 0.038)., Conclusion: VHF ultrasound imaging provided an early in vivo diagnosis of corneal epithelium pathology induced by chronic exposure to a preserved glaucoma drug, before the first clinical evidence of ocular toxicity. It could be a new reproducible method to detect the toxicity of glaucoma medication so that therapy can then be adapted., (Copyright 2008 S. Karger AG, Basel.)

We report a case of PEComa (or perivascular epithelioid cell tumor) in an unusual articular localization in a 13-year-old boy. The tumor, of 4 cm in diameter, showed an infiltrative pattern and was composed of both epithelioid and spindle cells with clear to granular eosinophilic cytoplasm and some multinucleated giant cells. Focal nuclear pleomorphism was present and we found up to 2 mitotic figures /50 high power field. There was no necrosis. Immunohistochemistry showed HMB-45 and smooth muscle actin positivity. Ultrastructurally, premelanosomes were present. Some rare cases of PEComa were reported in the soft tissues. The immunohistological profile (HMB-45 and smooth muscle actin positivity and PS-100 negativity) is helpful to the diagnosis. The histological prognostic criteria of these tumors are not well established. We discuss here the differential diagnosis, notably clear cell sarcoma of soft tissue.

The aim of this study was to investigate the in vitro vasomotor properties of rat extra-and intralobar pulmonary veins (PVs) related to their localization and to assess the modulatory role of endothelium on these properties. Segments from PVs were mounted in small vessel myograph and stretched at various diameters (D(10), D(20), D(30)) corresponding to intraluminal pressures of 10, 20 or 30 mmHg. At D(10) or D(20), contractile responses to phenylephrine, U46619 and angiotensin II of distal intralobar part of PVs were smaller compared with those of proximal extralobar part, but no longer different when distal part was stretched at D(30). When submitted to an NO donor, sodium nitroprusside, distal part of PV relaxed more strongly when stretched at D(30) compared with D(10). Acetylcholine and bradykinin were devoid of relaxing effect on distal parts stretched at D(10), but in contrast to acetylcholine, bradykinin slightly relaxed preparations stretched at D(30). Isoprenaline strongly relaxed PVs ( approximately 80% of initial precontraction), with the distal part exhibiting a higher sensitivity to the agonist compared with the proximal part. This relaxation was also observed with salbutamol and suppressed with ICI 118551, which is in favour of the involvement of beta(2)-adrenoceptors in this effect. Preincubation of the preparations with N(G)-nitro-l-arginine methyl ester (10(-4) m) and indomethacin (10(-5) m) did not modify the contractile responses to U46619, nor the relaxing response to isoprenaline, which support that endothelium does not appear to play a significant modulatory role in these responses. Histological and electron microscopical examinations of proximal and distal sections of the same vein show that the layers of smooth muscle cells and cardiomyocytes were thicker in the proximal compared with the distal part. This study shows that, because of morphological heterogeneity of the PVs, the site of dissection and the initial condition of tension can play a significant role upon the sensitivity and the magnitude of the responses to both contractile and relaxing agonists.

Platelet interactions with collagen are orchestrated by the presence or the migration of platelet receptor(s) for collagen into lipid rafts, which are specialized lipid microdomains from the platelet plasma membrane enriched in signalling proteins. Electron microscopy shows that in resting platelets, TIIICBP, a receptor specific for type III collagen, is present on the platelet membrane and associated with the open canalicular system, and redistributes to the platelet membrane upon platelet activation. After platelet lysis by 1% Triton X-100 and the separation of lipid rafts on a discontinuous sucrose gradient, TIIICBP is recovered in lipid raft-containing fractions and Triton X-100 insoluble fractions enriched in cytoskeleton proteins. Platelet aggregation, induced by type III collagen, was inhibited after disruption of the lipid rafts by cholesterol depletion, whereas platelet adhesion under static conditions did not require lipid raft integrity. These results indicate that TIIICBP, a platelet receptor involved in platelet interaction with type III collagen, is localized within platelet lipid rafts where it could interact with other platelet receptors for collagen (GP VI and alpha2beta1 integrin) for efficient platelet activation.

Purpose: To assess in vivo the corneal epithelial damage caused by a topical toxic medication using a 60-MHz ultrasound device., Material: and methods: A solution of timolol with 0.01% benzalkonium chloride (BAC) was applied twice a day in the test eyes of ten rabbits, and a BAC-free solution of timolol in the control eyes, for 56 days. We used a 60-MHz ultrasound device to evaluate the epithelial damage in BAC-exposed eyes, compared to control eyes. The clinical and ultrasound examinations were performed every week, and the histological analysis at the end of the experiment., Results: The clinical findings were conjunctival redness, corneal staining and instability of the tear film. In vivo VHF ultrasound revealed a thinning of the epithelium of test eyes (from 40.9+/-1,6 microm at D0 to 31.8+/-3.4 microm at D56; p=0.0006 for D0 vs D56), while the epithelium of control eyes remained unchanged. Ultrasound epithelial thickness was correlated with corneal staining (at D34 and D56; p=0.0025 and 0.0377, respectively) and histological epithelial pachymetry (p=0.0176 for control and 0.0505 for tested epithelium). Moreover, we report qualitative VHF ultrasound imaging of early epithelial damage., Conclusion: This new device could be very useful in ocular toxicity evaluation as a reproducible and reliable tool for multicentric clinical research.

Introduction: Dissection of cervical arteries is a frequent cause of stroke in young subjects., Case Report: We report the case of a 34-year-old patient who experienced simultaneous dissection of both internal carotid arteries and both vertebral arteries leading to repeated motor deficit of the right half-body associated with persistent otalgia. Search for an etiology led to the diagnosis of Ehlers-Danlos syndrome type IV., Conclusion: Search for the cause of cervical artery dissection must consider connective tIssue disease, particularly vascular forms of Ehler-Danlos syndrome. Diagnostic, therapeutic as well as prognostic aspects are discussed.

We report three cases of endophthalmitis following cataract extraction. Enterococcus faecalis was the causative organism in all of them. Initial visual acuity was only light perception in all cases, final visual acuity was negative light perception in two cases, and light perception in one case. After initial improvement, inflammation was exacerbated in one patient and evisceration realized. The capsular bag was examined using scanning electron microscopy and it was shown that enterococci were adherent to the capsular bag, four months after the onset of the infection. Enterococcus faecalis can be the causative agent both of an acute and a chronic form of post operative endophthalmitis. Experimental studies on rabbit eyes could explain the poor prognosis of these endophtalmitis and focused on bacterial toxins. The contamination appears to be post operative, because Enterococcus faecalis is not a commensal agent of the conjunctiva. So we have to inform our patients about some hygienic habits, to prevent from this devastating complication of cataract surgery.

The formation of biofilm results in a major lifestyle switch that is thought to affect the expression of multiple genes and operons. We used DNA arrays to study the global effect of biofilm formation on gene expression in mature Escherichia coli K-12 biofilm. We show that, when biofilm is compared with the exponential growth phase, 1.9% of the genes showed a consistent up- or downregulation by a factor greater than two, and that 10% of the E. coli genome is significantly differentially expressed. The functions of the genes induced in these conditions correspond to stress response as well as energy production, envelope biogenesis and unknown functions. We provide evidence that the expression of stress envelope response genes, such as the psp operon or elements of the cpx and rpoE pathways, is a general feature of E. coli mature biofilms. We also compared biofilm with the stationary growth phase and showed that the biofilm lifestyle, although sharing similarities with the stationary growth phase, triggers the expression of specific sets of genes. Using gene disruption of 54 of the most biofilm-induced genes followed by a detailed phenotypic study, we validated the biological relevance of our analysis and showed that 20 of these genes are required for the formation of mature biofilm. This group includes 11 genes of previously unknown function. These results constitute a comprehensive analysis of the global transcriptional response triggered in mature E. coli biofilms and provide insights into its physiological signature.

Tumour cell adhesion to vascular extracellular matrix (ECM), an important step of metastatic progression, is promoted by platelets. The aim of our study was to investigate, in whole blood under venous and arterial shear conditions, the respective role of tumour cell alphavbeta3 and platelet alphaIIbbeta3 integrins in MDA-MB-231 breast adenocarcinoma cell adhesion to human umbilical vein endothelial cell ECM. For that purpose, blood containing MDA-MB-231 cells was incubated with non-peptide antagonists specific for platelet alphaIIbbeta3 (lamifiban) or tumour cell alphavbeta3 (SB-273005). At 300 s(-1), each antagonist used alone did not modify tumour cell adhesion, whereas, at 1500 s(-1), tumour cell adhesion was decreased by 25% in presence of lamifiban indicating a role of platelet alphaIIbbeta3 at higher shear rate. However, a combination of SB-273005 and lamifiban, or c7E3 Fab (a potent inhibitor of both alphaIIbbeta3 and alphavbeta3) inhibited tumour cell adhesion by 40-45%, at either shear rate applied, indicating a cooperation between these two integrins in MDA-MB-231 cell adhesion to ECM, as well as the participation of other adhesive receptors on tumour cells and/or platelets. Thus, efficient anti-metastatic therapy should target multiple receptors on tumour cells and platelets.

The use of low-frequency ultrasound has been proposed to enhance the transdermal transport of various drugs, a technique referred to as sonophoresis. The aim of the present study was to determine the safety of low-frequency sonophoresis on human and rat skin by evaluating their structural modifications after ultrasound exposure. Human skin samples and hairless rats were exposed to 20 kHz ultrasound in vitro and in vivo, respectively. Ultrasound was used with average intensities ranging from 0.25 to 7 W/cm(2) in pulsed or continuous mode. Hairless rats were also exposed to a heat source mimicking the temperature versus time profile during sonication. Skin samples were observed under optical and electron microscopy to detect any structural changes. Human skin samples exposed to intensities lower than 2.5 W/cm(2) showed no modification. For hairless rats, slight and transient erythema was observed after 2.5 W/cm(2) exposure, whereas deep lesions (dermal and muscle necrosis) were observed 24 hr later. These lesions were also observed when a plastic film was placed between the coupling medium and the animals' skin during sonication. In contrast, no histologic lesion could be seen when a heat source was applied to animal skin. Low-frequency ultrasound induces delayed and deep lesions in hairless rat skin at 2.5 W/cm(2) which are not only attributable to the increase in temperature at the skin surface during ultrasound exposure. By using the same ultrasound conditions, human skin seems to be less sensitive in vitro., (Copyright 2001 Wiley-Liss, Inc.)

We examined the spatial distribution of MMP-2 on the surface of human endothelial cells using immunofluorescence and confocal microscopy. Staining endothelial cells with MMP-2-specific antibodies revealed a punctate labeling at the basolateral side of the cell periphery, which colocalized with patches of caveolin-1, a major constituent of the caveolae. This colocalization was confirmed by immunogold electron microscopy. MT1-MMP, TIMP-2, and the alphavbeta3 integrin exhibited a similar pattern of staining, with pericellular patches that colocalized with either MMP-2 or caveolin-1. The presence of MT1-MMP and TIMP-2 in caveolae patches could be seen only after treatment with concanavalin A, which induced MMP-2 activation but had no noticeable effect on the pattern or intensity of MMP-2 immunostaining. In contrast, MMP-9 and TIMP-1 staining showed a pattern completely different from that of MMP-2 and TIMP-2, with positive spots uniformly distributed throughout the cell body. Our data show that MMP-2, its activator the MT1-MMP, and its proposed receptor, the alphavbeta3 integrin, are all targeted to the same membrane microdomains on the endothelial cell, thereby restricting matrix proteolysis to a limited microenvironment at the cell surface., (Copyright 2001 Academic Press.)

Objective: Desquamative gingivitis is a chronic diffuse inflammation of the gingiva. The aim of this study was to determine the causes and the clinical characteristics of desquamative gingivitis., Patients and Methods: This was a retrospective descriptive study including 33 consecutive patients (25 women and 8 men) seen at a dermatology clinic for erosive gingivitis., Results: Thirteen patients (39 p. 100) had cicatricial pemphigoid, 12 (36 p. 100) had lichen planus, and 5 (15 p. 100) had pemphigus. Delay to diagnosis was a mean 19 months. The pinch sign was positive in 12 of the 13 cases of cicatricial pemphigoid. Dapsone improved the buccal lesions of cicatricial pemphigoid in all cases. Systemic corticosteroid therapy and acitretine were the most effective treatments for lichen planus and corticosteroid therapy improved pemphigus in all cases. At the time of assessment, only 3 cases of cicatricial pemphigoid, 2 cases of lichen planus and 1 case of pemphigus had reached complete remission without treatment., Discussion: Cicatricial pemphigoid and lichen planus are the most frequent causes of desquamative gingivitis, accounting for three-quarters of the cases. Positive diagnosis may be difficult and may require sophisticated techniques to avoid delay. Despite the effectiveness of symptomatic treatment, desquamative gingivitis may have a long course.

The aim of this study was to determine the role of Magnetic Resonance Imaging (MRI) in investigating fetal cerebral lesions induced by long term exposure to cocaine during sheep pregnancy. Cerebral Magnetic Resonance Imaging was performed on two groups of fetuses at 125 days of gestation (normal gestation: 145 days). The control group consisted of eight fetuses of four pregnant ewes. The study group consisted of eight fetuses of four pregnant ewes receiving daily 140 mg/kg injection of cocaine from day 60 until delivery. The following MR sequences were applied: T1-weighted FLASH, and T2-weighted Fast-Spin-Echo. Cerebral images were evaluated semi quantitatively using the following criteria: Heterogenicity, contrast between grey and white matter, contours irregularity, hyposignal, lateral ventricle sizes. The brightness distribution and homogenicity of the images were analysed by means of edge pair distributions using a new computerized method originally designed for ultrasound images analysis developed by Ultrasight inc (USA). (1) Flash T1: Heterogenic areas and irregular contours were more frequent in cocaine exposed fetuses. The contrast between grey and white matter was more important in the cocaine group. Hyposignal was found only in the cocaine group. Enlarged lateral ventricle occurred more frequently in the cocaine group. (2) Spin echo T2: The contrast between grey and white matter was higher and the contours of the brain more irregular in the cocaine group. Heterogenicity and hyposignal were also more frequent in this group but the difference with the control group was not significant. The computerized analysis of the contrast density on the cerebral images showed that 88% of the areas exceeding the reference level concerned the cocaine group, while only 14% of the areas exceeding the reference level concerned the control group. Long term exposure to cocaine induces cerebral tissue modifications, in favor of an advanced maturation and the development of hypoxic lesions. The histology of the brains confirmed in the cocaine group, the existence of hypoxic lesions with gliosis, perivascular edema and hemorrhages, and neuronal death.

Purpose: To localize the collagen type VI, laminin et fibrillin in glaucomatous and non-glaucomatous trabecular meshworks., Material: Twenty-four trabeculectomy specimens from patients suffering of primary open angle glaucoma (POAG, 15 cases), pigmentary glaucoma (PG, 2 cases), pseudo-exfoliative glaucoma (PEG, 7 cases) and 2 non glaucomatous aged trabeculums of enucleated eyes., Methods: Post-embedding immunogold indirect labelings on 4% paraformaldehyde-0.1% glutaraldehyde fixed and LRWhite embedded samples., Results: Labeling of type VI collagen was observed on the 64 nm collagen fibers in all samples, less intensively on POAG or PG disorganised microfibril areas, and especially on PEG pseudo-exfoliative material deposits. Laminin labeling was strongly positive on healthy basal membranes and less intense on POAG and PG abnormal basal membranes. Fibrillin labeling was found on POAG or PG disorganized microfibril areas, especially around pigment granules, around 64 nm striated collagen fibers and with a mild intensity on POAG and PG juxtacanalicular microgranular substance areas. No labeling was found on pseudo-exfoliative substance deposits., Conclusion: Collagen type VI abundance in pseudo-exfoliative substance deposits could result from a fibrillogenesis abnormality. POAG and PG basal membrane ultrastructural abnormalities and weak laminin content could share the origin. The abundance of fibrillin in disorganized microfibrils could result from the chronic elevated tensile strength due to ocular hypertony.

Objective: To check the potential usefulness of clinical criteria for the diagnosis of bullous pemphigoid when state-of-the-art techniques such as Western immunoblotting, immunoprecipitation, and indirect immunofluorescence on salt-split skin or direct immunoelectron microscopy are not available., Design: Comparison of the clinical criteria between 2 groups (with and without bullous pemphigoid) as defined by immunoelectron microscopy used as standard criterion, in a prospective study. Multivariate logistic regression analysis was carried out by including all items that were statistically significant (at P < .05 level) in univariate analysis., Setting: Five dermatology departments in teaching hospitals., Patients: The 231 patients studied had subepidermal autoimmune bullous diseases with linear IgG or C3 deposits in the basement membrane zone (157 with bullous pemphigoid, 33 with cicatricial pemphigoid, 30 with epidermolysis bullous acquisita, 5 with lupus erythematosus, and 6 others). A second set of patients was used to calculate predictive values., Results: The multivariate logistic stepwise analysis resulted in a final set of predictors that included only 4 items: absence of atrophic scars, absence of head and neck involvement, absence of mucosal involvement, and age greater than 70 years. No additional variables met the .05 significance level to enter into the model. If 3 of these 4 characteristics were present, a diagnosis of bullous pemphigoid could be made with a sensitivity of 90% and a specificity of 83%; these predictive values were calculated on a sample of 70 new cases., Conclusions: With and estimated incidence of bullous pemphigoid among subepidermal autoimmune bullous diseases of 80%, the presence of 3 of the 4 significant criteria allows the diagnosis of bullous pemphigoid, with a positive predictive value of 95%. Our set of clinical criteria thus allows the diagnosis of bullous pemphigoid with good validity for both clinical practice and therapeutic trials.

In a previous study, we have demonstrated that the platelet adhesive glycoprotein thrombospondin-1 (TSP-1) interacts specifically with the cytoskeletal protein alpha-actinin in a solid-phase binding assay. Stored in the alpha-granules of platelets, TSP-1 is secreted during cell activation and binds to the plasma membrane promoting the platelet macroaggregate formation. However, the molecular mechanism by which TSP-1 reaches and binds to the platelet surface is to date unelucidated. alpha-Actinin is an actin-binding and actinin-cross-linking protein that is present in most cells and may act as a link between the bundles of F-actin and the plasma membrane. In this study, we have investigated a possible interaction of alpha-actinin with TSP-1 in platelets by examining their respective subcellular location during the platelet activation process. By indirect immunofluorescence. alpha-actinin was found to display a granular staining in resting platelets similar to that of TSP-1. Performing postembedding immunogold labeling for electron microscopy, we detected the presence of alpha-actinin throughout the cytoplasm, but the strongest gold staining was found in organelles identified as alpha-granules on the basis of their ultrastructure and TSP-1 content. With the use of double immunogold labeling on platelets at different stages of activation by thrombin, both alpha-actinin and TSP-1 were seen redistributing from the alpha-granules to the platelet surface via the open canalicular system (OCS). At the same time, the cytoplasmic alpha-actinin concentrated toward the plasma membrane, but no colocalization with the F-actin bundles was evidenced. Finally, preembedding immunogold labeling and immunoprecipitation of 125I-surface-labeled, thrombin-activated platelets further demonstrated that alpha-actinin was expressed on the plasma membrane in the absence of any detectable expression of actin and that it could from molecular complexes with TSP-1 on activated platelets. These results suggest that alpha-actinin found to be present on the platelet surface together with TSP-1 originates in the alpha-granules by fusion of the alpha-granules with the plasma membrane during platelet exocytosis.

The so-called Dorello's canal was studied in 32 specimens (16 human cadaver heads) injected with colored latex and fixed in formalin (28 specimens) or studied with microscopic and ultrastructural methods (four specimens). To avoid the differences usually encountered in the description of this area, the authors preferred to consider a larger space that they have named the petroclival venous confluence (PVC). It was located between two dural layers: inner (or cerebral) and outer (or osteoperiosteal). The PVC was quadrangular on transverse section. The posterior petroclinoid fold and the axial plane below the dural foramen of the abducent nerve (sixth cranial nerve) limited the PVC at the top and bottom, respectively. Its anteroinferior limit was the posterosuperior aspect of the upper clivus and outer layer of the dura mater. Its anterior limit was the vertical plane containing the posterior petroclinoid fold, and its posterior limit was the inner layer of the dura. The PVC was limited laterally by the medial aspect of the petrous bone apex and medially by the virtual sagittal plane extending the medial limit of the inferior petrosal sinus upward. The PVC was a venous space bordered by endothelium and continuous with the cavernous sinus, the basal sinus of the clivus, and the inferior petrosal sinus. There were trabeculations between the two dural layers. The petrosphenoidal ligament of Gruber may be regarded as a larger trabeculation, and it divided the PVC into a superior and an inferior compartment. The abducent nerve generally ran through the inferior compartment, where it was fixed to the surrounding dura mater. This nerve was only separated from venous blood by a meningeal sheath of varying thinness lined with endothelium. The clinical implications of these findings are discussed.

We report the results of an immunogold electron microscopical analysis on microfibrils from the arterial subendothelium showing that thrombospondin (TSP) is present on 40 nm-diameter structures joining 8-10 nm-diameter microfibrils containing fibrillin. They differ from type VI collagen which forms 3-5 nm-diameter microfibrils. TSP containing microfibrils (TSP-MF) extracted from human umbilical arteries did not contain fibrillin or type VI collagen. Blood platelet interactions with TSP-MF were not modified by anti-fibrillin or anti-type VI collagen antibodies. In situ, vWF was bound to cross-linked microfibrils, at the level of their 40 nm junction, and a double-labeling with the anti-thrombospondin and anti-vWF antibodies was observed. In vitro, vWF binding to TSP-MF was not inhibited by anti-fibrillin or anti-type VI collagen antibodies. These results suggest a structural and functional heterogeneity of microfibrils and emphasize the role of TSP-MF in the thrombogenicity of the subendothelium.

To evaluate the involvement of the glycoprotein (GP) IIb/IIIa-dependent process in platelet deposition and thrombus growth on capillaries coated with human type III collagen, the effects of incremental doses of Lamifiban, a potent specific synthetic GPIIb/IIIa antagonist, were studied in ex vivo capillary perfusion chambers using guinea pig blood. In this model, nonanticoagulated blood was perfused for 4.5 minutes at three shear rates: 100, 650, and 1600 s-1. Platelet deposition was quantified by computer-assisted morphometry and expressed as platelet adhesion (percentage of capillary surface covered with spread and contact platelets and platelets implicated in thrombus), mean thrombus height, and total thrombus cross-sectional area. In control untreated guinea pigs, platelet adhesion and thrombus height were 63% and 2.5 microns at 100 s-1, 60.5% and 13.8 microns at 650 s-1, and 45% and 28.1 microns at 1600 s-1, respectively. At 100 s-1, Lamifiban had no effect on platelet deposition at any of the three doses administered to the guinea pigs (0.3, 1, and 3 mg/kg). At 0.3 mg/kg and shear rates of 650 and 1600 s-1, Lamifiban had no effect on platelet adhesion or thrombus size, but at 1 and 3 mg/kg and shear rates of 650 and 1600 s-1, it significantly reduced thrombus size. At 1600 s-1, 1 mg/kg Lamifiban significantly increased platelet adhesion from 45% to 62.5%, whereas at 3 mg/kg it induced a significant overall decrease from 45% to 25% and qualitatively increased the ratio of contact to spread platelets. These data suggest that at high shear rates, GPIIb/IIIa participates in platelet spreading and that there is a balance between platelet involvement in adhesion to the thrombogenic surface and the growth of the already formed thrombus. This indicates that important clinical implications of an optimal therapeutic degree of GPIIb/IIIa antagonism could be expected.

Introduction: Elastosis perforans serpiginosa frequently occurs in trisomy 21. Usually no cause is found. We report a case in which vitamin deficiency may have contributed to the development of skin lesions., Case Report: A 11-year-old girl with trisomy 21 developed papulokeratosic eruptions with a linear serpiginous distribution, predominantly involving the lower limbs. On ultrastructure examination, numerous elastic fibers penetrated the epiderma and the baseline membrane had disappeared. The patient also had a totally patent atrioventricular canal with hypoplasia of the left ventricle and cardiac liver. Serum vitamin A level was low (0.56 mumol/l, normal > 1.55). Acitretine was prescribed at the dose of 0.5 mg/kg/day but had to be stopped 2 months later due to elevated liver enzyme levels despite a clear clinical improvement., Discussion: This association between elastosis perforans serpiginosa and vitamin A deficiency, observed here in a child with trisomy 21, has never been reported by others. Vitamin A deficiency might aggravate the skin lesions. In our case, there was probably a relationship between the vitamin A deficiency and the cardiogenic liver disease. The keratoregulatory effect of vitamin A on elastic tissue is less well known. Treatment with retinoids provided clinical improvement but had to be stopped due to hepatotoxicity. Parenteral vitamin A would be an interesting alternative but the risk of side effects would theoretically be greater than with oral retinoids.

Background: We studied the distribution of collagen types I, III, IV and VI in one healthy human cornea and in seven pathological human corneas, in which the disorders were three cases of pseudophakic bullous keratopathy (two severe, one moderate) and one case each of stage IV keratoconus, chronic ulcer, vascularized cornea and disciform keratitis., Methods: Transmission electron microscopy examinations were performed on post-embedding immunogold-labelled sections. The staining was evaluated by gold particle count in the different tissues. The presence or absence of a given antigen was determined by statistical analysis, using a d-value test., Results: Our results on healthy corneal tissues corroborate the data available from previous studies, except for collagen type VI, which we found to be absent in Bowman's layer. In pathological corneas with a collagenous layer posterior to Descemet's membrane, collagen types I, III and especially IV were detected in this collagenous layer. Collagen types I, III and VI were detected in the anterior healed stroma of other pathological corneas, except for the keratoconus cornea, in which intense collagen III staining was observed., Conclusion: The presence of collagen types I and III in the posterior collagenous layer of our pseudophakic bullous keratopathy corneas suggests that this layer corresponds to scar tissue secreted by stimulated endothelial cells.

Background and Design: The incidence and distribution of autoimmune subepidermal bullous diseases were estimated from prospective data (including immunoelectron microscopy) obtained from 100 cases during a mean period of 35 months in three university dermatologic centers in Amiens, Limoges, and Tours, France, that correspond to a cumulative reference population of 3.55 x 10(6)., Results: Using data from these regions, we found a mean annual incidence of autoimmune subepidermal bullous diseases to be 10.4 per million people and, therefore, estimated the overall number of new cases of these disorders in France to be about 590 cases per year. According to clinical and immunoelectron microscopic criteria, a precise diagnosis was established in 94 cases, distributed as follows: bullous pemphigoid, 69 cases; cicatricial pemphigoid, 12 cases; linear IgA dermatosis, five cases; herpes gestationis, four cases; epidermolysis bullosa acquisita, two cases; and vesiculobullous systemic lupus erythematosus, two cases., Conclusion: Our prospective study is the first assessing the incidence and distribution of autoimmune subepidermal bullous disorders that systematically included immunoelectron microscopic data. Our estimated incidence of bullous pemphigoid (seven new cases per million people per year) is large enough to establish bullous pemphigoid as the major autoimmune subepidermal bullous disease for the purpose of therapeutic trials. On the contrary, all other disorders, particularly epidermolysis bullosa acquisita (estimated annual incidence, 0.17 to 0.26 per million people), were very rare and reflect the paucity of patients available for short-term clinical studies in France.

Diagnostic procedures used in 9 cases of pseudo-uterus unicornis were presented. There are no manifestations of this malformation excepting during pregnancy and rare episodes of uncontrollable dysmenorrhoea. If pregnancy develops in the rudimentary cornis, major complications require hemihysterectomy.

Introduction: Degos' disease is a rare dermatosis characterized by papular lesions with a porcelain-white central atrophy and histopathological aspect of wedge-shaped infarction necrosis and an endovasculitis in the dermis. Its pathogenesis is unknown but many abnormalities of haemostasis have been reported., Patients and Methods: Platelets functions, coagulation and fibrinolysis were estimated in three patients with Degos' disease. For one patient, direct immunoelectron microscopy using an antibody to von Willebrand factor was performed on lesional skin., Results: In all the patients, prolonged euglobulin lysis time, increased plasminogen activator (PA) and plasminogen activator inhibitor (PAI) activities before and after a venous occlusion test were detected and indicated an inhibition of fibrinolysis. Electron microscopy demonstrated in one case an increased number of Weibel-Palade bodies and a raised staining of von Willebrand factor in endothelial cells. Tests for coagulation and circulating anticoagulant were normal. Results of platelets adhesion showed decrease of adhesion in one case and increased adhesion in another. Platelets aggregation studies were normal in two cases and showed hyperactive spontaneous and induced aggregation in one case., Conclusion: We showed an inhibition of fibrinolysis in three patients with Degos' disease. These abnormalities could induce a prethrombotic state. The release of PA and PAI from the endothelial cells into the blood stream and the modifications observed with electron microscopy may signify a primary lesion of endothelial cell of still unknown origin.

Autoimmune bullous diseases have been reported associated with different causal factors: drugs, mechanical trauma and physical trauma, particularly ultraviolet light and radiotherapy. In these cases different hypotheses regarding the pathogenesis of blister formation can be supported. In this observation, we report a localized cicatricial pemphigoid with unusual clinical presentation. Moreover, it appeared 9 years after radiotherapy for breast carcinoma and it was preferentially localized on an upper limb lymphoedema. Because of the long time between the treatment of carcinoma with radiotherapy and the onset of pemphigoid, we assume that lymphoedema played a major etiological role in this particular cicatricial pemphigoid.

We present an easy method in which the adhesion of platelets to collagen or to MFs was measured in a spectrophotometer, after an incubation of hypercitrated platelet rich plasma (PRP), or of a platelet suspension, with an inducer, followed by the filtration of non adhering platelets through translucent Isopore membrane filters (pore diameter = 5 microns). The adhering platelets, which are retained on the filter, were stained by Coomassie blue to quantify the adhesion by the simple reading of the O.D. 580 nm of the stained platelets which appear as a blue spot on the translucent membranes.

We describe a new case of signet ring cell peripheral T cell lymphoma in a 45-year-old man. This lymphoma had a very indolent course, since--without treatment--the clinical staging has shown no evidence of disease progression 11 years after initial symptoms. Immunophenotype indicated pan T antigens (Leu 4 CD3, Leu 1 CD5) and T suppressor cytotoxic antigen (IOT8 CD8) expression. Several T antigens (Leu 5b CD2, Leu 9 CD7, Leu 3a CD4) were not expressed. The proliferation index was less than 5% with Ki 67 monoclonal antibodies. The ultrastructural study showed characteristic cytoplasmic vacuoles containing microvesicles. Five cases of signet ring T cell lymphoma, which were very similar to our case, have been previously described. Their characteristics were primary cutaneous presentation, indolent course, good response to current therapies and a long survival period. The indolent course of these signet ring cell lymphomas may indicate that this type of lymphoma is a low grade malignant lymphoma and not only a morphological pattern.

The purpose of the study was to describe the architecture of accretions occurring in endotracheal tubes used in adults by using a conservative procedure and transmission electron microscopy. The study included 12 tubes for which microbiological data of the tracheobronchial secretions were available. Observations were performed on inducted areas of the lumen. All tubes were covered with a several micrometers-to several millimeters-thick layer of mucus. The layers displayed stratified structures and showed granulations, neutrophils or cellular elements. When bacteria were seen, they made no contact with the polymer. This data suggest that adherence properties of bacteria towards the polymer were not involved at these stages of colonization and that a bacterial biofilms is a rare opportunity.

Schnitzler's syndrome, first described in 1974, is defined by chronic non-pruritic urticaria, osteocondentation, and a monoclonal IgM dysproteinemia, but without criteria of lymphoproliferative disease. We report a patient with chronic urticaria and macroglobulinemia. In addition, he had double monoconal dysproteinemia IgM kappa (31.3 g/l) and IgA lambda, osteocondensation, and some cutaneous lesions of pseudoxanthoma elasticum. Only 20 cases of Schnitzler's syndrome have been reported hitherto. This is the first case associated with pseudoxanthoma elasticum, which was localized and discovered at the same time as Schnitzler's syndrome. We discuss the possible role of monoclonal immunoglobulin in the occurrence of localized elastorrexhis.

A 27-year-old man presented with relapsing vascular limb purpura, pulmonary infiltrates and cranial nerve palsies occurring after exposure to pigeons. A lung biopsy specimen showed Churg-Strauss angiitis. Actinomycetes were observed in pneumocytes. The circumstances preceding clinical manifestations and pathologic findings favored the diagnosis of pulmonary vasculitis as a consequence of inhaled antigen. Recovery was obtained after treatment with prednisone, cyclophosphamide, and plasma exchanges.

Polyurethane (PU) and polyethylene (PE) catheters were distributed by randomization among adult ICU patients to evaluate the impact of the catheter polymer on the rate of catheter-related sepsis (CRS). The two catheters were otherwise strictly identical. Three hundred central venous catheters were randomized and inserted in the subclavian or internal jugular vein, at the discretion of the clinician. Mean duration of insertion was 9.2 (+/- 3) days for both catheter types and mean number of line openings was 159 (+/- 60). A bacteriologic culture using a variant of Maki's technique was performed on the 205 catheters removed before patient discharge. No significant differences were found between the two catheters. Total number of tip infections was 33 and polyurethane and polyethylene prevalence ratio was 0.7. A clinical evaluation was performed for the 183 catheters inserted for a least 48 hours (in 142 patients). Patients were divided into four clinical categories according to previously reported definitions (Brun-Buisson et al., 1987). Clinical tip-infection rate was 4.4% and polyurethane and polyethylene ratio was 0.7. For three additional catheters (1.6%), only the Luer-lock was infected. These three catheters were made of polyethylene and were inserted into the internal jugular vein. The Luer-lock was made of polypropylene.

The purpose of this study was to determine the nature of the argyrophilic cells in the ectocervix and to analyze the different morphologic varieties of argyrophil cell-containing ectocervical epithelia, notably to reappraise the degree of analogy with transitional epithelium. A systematic study of 39 ectocervices was carried out using histochemical and immunohistochemical techniques. Immunodetection of cytokeratins was used to specify the differentiation of the ectocervical linings. Argyrophilic cells were detected in 43% of our specimens. They have been found in several varieties of ectocervical lining: normal-appearing or hyperkeratotic squamous epithelium, "transitional-like" epithelium extending onto the portio, and immature squamous metaplasia from the transformation zone. The term "transitional-like" refers to a stratified nonsquamous epithelium that differs from true urothelium by the absence of superficial differentiation leading to the layer of "umbrella" cells. Two main types of argyrophilic cells have been delineated: serotonin cells and Merkel-type cells. The nature of the argyrophilic cells was dependent on the type of epithelium: Serotonin cells were essentially associated with "transitional-like" epithelium and Merkel-type cells with squamous epithelium. The latter cells were particularly frequent in hyperkeratotic squamous epithelium from uterine prolapse, reinforcing the homology with epidermis.

The regeneration of the myelinated fibers has been studied after a localized congelation or a section followed by an immediate suture in the left sciatic nerve of rats aged of 1 1/2, 3, 6, 12, 18 and 24 months at the moment of the operation. The regenerated fibers has been observed in the left internal gastrocnemius nerve, the right nerve being considered as the sham. For each nerve, the number and the caliber of the myelinated nerves has been systematically registered at standard levels allowing to calculate the average diameter of the fibers, their repartition and to draw their histogram. The results seem to prove that the potential of regeneration is correlated to the age, the velocity and intensity of the axonal growth decreasing in the old age. This potential of regeneration remains during the whole life. The integrity of the schwannian membranes considerably facilitates the nervous fibers regeneration, their interruption is a major obstacle to the axonal regrowth.

The number and the average diameter of the myelinated fibers have been recorded in the both medial gastrocnemius nerves in the rat. The study concerned foetus at the end of the intra-uterine life as well as old rats (24 months). It seemed the absolute necessity to collect these data before studying the consequences of age on nervous regeneration. Electron microscopy was used in very small samples, photonic microscopy in bigger ones. The first myelinated fibers appear during the first day of life. Their number becomes steady around 2 months of live. But their diameter changes and increases until the end of the 6th month. In pubescent animals, the global variations between the two sides are negligible (average right number 260 +/- 8 fibers, average left 258 +/- 12, average right diameter 1.7 +/- 0.7 microns, average left diameter 7.1 +/- 0.6 microns).

A case of a peculiar papillary neoplasia of the vagina resembling a urothelial tumour is presented. Four vaginal tumours were excised from a 76-year-old woman. Five years before this patient had undergone a uretero-nephrectomy for a non-invasive papillary transitional cell carcinoma of the renal pelvis. The four vaginal tumours demonstrated gross and microscopic similarities to low-grade papillary transitional cell carcinoma of the urinary tract. This observation indicates that multicentric, non-invasive, papillary tumours may affect the whole uro-genital area. The vaginal wall was not overlaid by a normal squamous epithelium, but by a peculiar "transitional-like" epithelium. Variegated endocrine cells were documented within this lining, using immunohistochemical and ultrastructural techniques. The eventuality of a histogenetic link between the tumour and the adjacent epithelial lining remains unresolved.

The relationship between the presence of hepatitis B virus antigens, their localization and hepatitis B virus replication was studied in different clones of cultured HepG2 hepatoblastoma cells transfected with cloned hepatitis B virus DNA. Intracellular hepatitis B virus antigens were detected by immunofluorescence. The production of these antigens was evaluated in the culture media by enzyme-linked immunoassay. Hepatitis B virus DNA was detected using dot-blot hybridization. Three types of HBcAg staining were observed in transfected HepG2 cells: (a) cells with nuclear HBcAg, (b) cells with cytoplasmic HBcAg and (c) cells with both nuclear and cytoplasmic HBcAg. Cell types b and c also expressed hepatitis B virus DNA in their culture media. Our results suggest that cytoplasmic HBcAg may be more involved than nuclear HBcAg in hepatitis B virus replication. The site of hepatitis B virus formation in hepatocytes was studied by electron microscopic examination of a specific hepatitis B virus producer clone, thereby allowing detection of intracellular Dane particles more easily than liver biopsy samples from infected patients. Dane particles and HBsAg filaments were found in large, dilated structures probably related to the endoplasmic reticulum. Budding of core particles into cisternae of endoplasmic reticulum-related structures appears to be a possible mechanism for hepatitis B virus formation; our results suggest that the exocytosis of cisternae to extracellular spaces may be a mechanism for release of hepatitis B virus particles.

Six months before consulting, a 71-year old man developed buccal and genital erosions which gradually became worse. Physical examination showed signs of superficial desquamative gingivitis, wide erosions on the bony palate, erythemato-erosive balanoposthitis and 7 bullae or skin erosions on the upper part of the back. At histopathological examination of a cutaneous bulla there was dermoepidermal cleavage and an inflammatory infiltrate without eosinophils. At direct immunofluorescence, linear deposits of IgG and C3 were present along the basement membrane. A search for anti-skin autoantibodies was negative at indirect immunofluorescence but positive at immunoblotting (240 Kd band). The cicatricial pemphigoid was treated with dapsone alone in doses of 100 mg/day. Treatment was continued for 6 months, resulting in complete cure of the mucosal and cutaneous lesions. An immunoelectromicroscopic study, performed according to the technique described by Prost et al., on a fragment of skin from around the bullae, showed deposits of granular IgG in the lamina lucida and the lamina densa and deposits of C3 in the lamina densa. This case of cicatricial pemphigoid exhibited 3 features which are not usually found in bullous pemphigoid. Clinically, the buccal lesions were located on the gums and on the hard palate, i.e. where the mucosa adheres to the underlying bone through the periosteum. This location is habitual in cicatricial pemphigoid and differs from that of the bullous pemphigoid lesions which affect the free mucosa lining the cheeks and the soft palate. Treatment with dapsone was dramatically successful in our patient whose lesions disappeared in 6 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Sneddon's syndrome consists of livedo reticularis and cerebral vascular accidents with no evidence of systemic disease responsible for the livedo. The syndrome has been assimilated to a subgroup of systemic lupus erythematosus (SLE) with presence of antibodies directed against phospholipids. Recently, a significant increase in the frequency of cardiac valve diseases has been demonstrated in some SLE patients with livedo reticularis, cerebral vascular accidents and antiphospholipid antibodies. We report the case of a 26-year old woman who had been presenting for 6 years with idiopathic livedo reticularis. Her history was remarkable for the occurrence of 2 cerebral ischaemic accidents at the ages of 23 and 26 years, generalized convulsive seizures at 22 years, and hypertension of pregnancy with 2 miscarriages. Biopsy of the livedo showed normal histological patterns, but electron microscopy detected an obliterating endothelial proliferation and endothelial cells with numerous Weibel-Palade bodies. Laboratory signs of SLE, as well as antiphospholipid antibodies were absent. At the age of 26 years, cardiac abnormalities were heard at auscultation for the first time, and echocardiography showed that they were due to a fairly loose mitral stenosis. According to Burton's criteria our patient had all the typical features of Sneddon's syndrome. The finding of mitral stenosis--an emboligenic cardiopathy that is potentially responsible for cerebral vascular accidents--raises the problem of its relationship with Sneddon's syndrome. The association does not seem to be fortuitous, since our case is very similar to the cases of SLE or antiphospholipid antibody syndrome associated with cardiac valve lesions. However, this case is particular in that 6 years after the onset of the disease there was still no sign of SLE and of antiphospholipid antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)

This study was devoted to a peculiar population of argyrophilic cells present among various stratified squamous epithelia. The purpose of the study was to determine the distribution and the nature of these argyrophilic cells, and to reappraise their degree of analogy with the Merkel cells of epidermis. Examples of squamous epithelia from skin, exocervix, anal canal and dermoid cyst of ovary were investigated using histochemical, immunohistochemical and ultrastructural techniques. Melanin-containing cells as well as peculiar argyrophilic cells were revealed in each series of specimens. These peculiar argyrophilic cells expressed EMA, chromogranin A and NCL-5D3 (cytokeratins 19, 18, 8) immunoreactivities. By contrast, they were serotonin negative. An intense staining for EMA was observed. These cells were obviously endocrine cells. Ultrastructural studies confirmed the presence of endocrine cells within the anal canal and the exocervix; moreover, in anal canal, some of these cells appeared to have contacts with a nerve terminal. Through the epidermis, these cells can only correspond to Merkel cells, because of their chromogranin positivity. Throughout other squamous epithelia, this population of endocrine cells (serotonin negative) bear some analogies with Merkel cells of epidermis. Their distribution, morphology, EMA immunoreactivity and ultrastructural appearance were reminiscent of those of the Merkel cells. They could be named Merkel-type cells. Additional studies, using other characteristic or specific markers of Merkel cells, are clearly required to determine the exact degree of analogy between these types of cells. Merkel-type cells could be largely distributed through stratified squamous epithelia from various tissues. They can be easily visualized by their strong EMA immunoreactivity and must be distinguished from Paget cells.

The purpose of this study was to determine tissue distribution of certain cytokeratins along the ectocervical lining. A series of 20 cases was investigated by immunocytochemical labelling with specific antibodies against cytokeratins 19, 18, 8, 7, 10. Monoclonal antibodies were used on frozen sections. Distribution of keratin or alteration in expression was correlated with morphologic changes. All specimens were lined by a normal stratified squamous epithelium which was devoid of argyrophilic cells. Low molecular weight cytokeratins 8, 18, 19 (normally expressed in simple epithelia) were consistently and exclusively expressed through out the basal cell layer of the ectocervical lining. Some other particular immunostainings have been noted. A peculiar staining pattern was observed around some stromal papillae. Development of papillae was accompanied by the expression of cytokeratin 10 (which is commonly detected in skin), and by a reduction in the level of expression of simple epithelial cytokeratins. In addition, in the middle zone, anticytokeratin 10 revealed a mosaic of positive and negative cells even in light microscopically non keratinizing squamous epithelium, with differences of expression from case to case.