Ultrastructural anatomy of CALT follicles in the rabbit reveals characteristics of M-cells, germinal centres and high endothelial venules

Conjunctiva-associated lymphoid tissue (CALT) is a part of the eye-associated lymphoid tissue (EALT) at the ocular surface. Its lymphoid follicles are usually characterized by using light microscopy, but its ultrastructure remains largely unknown. In this study, flat whole-mount conjunctival tissues (n = 42) from 21 young adult rabbits were investigated native in reflected light, and further stained and cleared (n = 6), in paraffin histology sections (n = 6), scanning electron microscopy (SEM, n = 4) and transmission electron microscopy (TEM, n = 4). Secondary lymphoid follicles accumulated into a dense group nasally towards the lacrimal punctum of the lower lid. High endothelial venules (HEV) with typical ultrastructure occurred in the parafollicular zone. The bright germinal centre (GC) contained lymphoblasts, follicular dendritic cells, apoptotic cells and tingible body macrophages. The follicle-associated epithelium (FAE) was devoid of goblet cells and contained groups of lymphoid cells. TEM showed these cells to be located in cytoplasmic pockets of superficial electron-lucent cells with a thin cytoplasmic luminal lining that contained a fine filament meshwork and numerous endocytotic vesicles. These M-cells were sitting between and on top of the ordinary dense epithelial cells that were located basally and formed pillar-like structures. In stereoscopic SEM, the surface cells were very large, had a polygonal outline and covered cavernous spaces. The rabbit has a CALT with typical follicular morphology, including HEV for regulated lymphocyte migration and epithelial cells with ultrastructural characteristics of M-cells that allow antigen transport as indicated by the GC-reaction. The arrangement of these M-cells on top of and between epithelial pillar cells may reflect a special structural requirement of the multilayered CALT FAE.     

Cytopathic effects of human papillomavirus infection and the severity of cervical intraepithelial neoplasia : A frequency study

Cytopathic effects related to the human papillomavirus (HPV) infection are more frequently found in cervical intraepithelial neoplasia (CIN) 1; however, there are indications that at least half the histological diagnoses of CIN2 and CIN3 include koilocytosis areas. The objective of this study was to evaluate the frequency of the cytological criteria suggestive of HPV infection in the cervical smears of women with a histological diagnosis of CIN. One hundred and sixty-two women with abnormal cervical smears and a diagnosis of CIN confirmed by histopathology were selected, including 46 cases of CIN 1, 42 of CIN 2 and 74 cases of CIN 3. Koilocytosis was found in 63% of the smears from women with a histopathological diagnosis of CIN 1. This sign was observed in 26.2% and 25.7% of smears of women with a diagnosis of CIN 2 and CIN 3, respectively. Cytomegaly also was frequent in cervical smears of women with histopathological diagnosis of CIN 1 (71.8%). On the other hand, spindle cells and atypical metaplasia were more frequent in women with CIN 2 and CIN 3. Atypical parakeratosis showed similar frequency in all grades of CIN diagnosis. Koilocytois and cytomegaly were inversely correlated with the diagnosis of CIN2 or CIN 3, with OR values respectively of 0.30 (95%CI 0.13-0.68) and 0.26 (95%CI 0.11-0.58). The others signs analyzed did not show any significant association. Koilocitosis and cytomegaly can provides good reassurance that a patient with atypical cervical smear have CIN 1.     

Polynorbornenes With Pendant Europium (III) Coordination Compounds

Europium‐containing monomers with different bidentate and tridentate N‐donor ligands carrying norbornoyl side chains and theonyl trifluoroacetylacetonate (TTA) as coligand are obtained and incorporated in random copolymers and amphiphilic block copolymers using ring‐opening metathesis polymerization (ROMP). The characteristic bright red long‐lived europium luminescence is retained in the polymers. The polymers are characterized (using ¹H NMR spectroscopy, gel permeation chromatography, differential scanning calorimetry, fluorescence spectroscopy, and dynamic light scattering) and tested as water vapor sensor materials. A sensitivity increase over time and changes in the luminescence spectra of the polymer samples indicate dissociation of Eu(TTA)₃ from the polymer chains.     

Induction of phenotype modifying cytokines by FERMT1 mutations

Kindler syndrome (KS) is a progressive skin disorder caused by FERMT1 mutations. Early in life, KS manifests as a mechanobullous disease reflecting diminished cell adhesion, but the mechanisms of its later phenotypic features, progressive poikiloderma, and mucocutaneous fibrosis, remain elusive. The FERMT1 gene product and KS protein, kindlin-1, is an epithelial-specific phosphoprotein involved in integrin beta-1 activation, without an obvious link to dermal connective tissue. Here we show how lack of intracellular kindlin-1 in epidermal keratinocytes leads to profound changes in another skin compartment, the dermis. Kindlin-1-deficient keratinocytes respond to cell stress by upregulating the expression of cytokines such as IL-20, IL-24, TGF-β2, IL1F5, PDGFB, and CTGF. These launch-via paracrine communication-an inflammatory response in the dermis, accompanied by the presence of TGF-β, IL-6, and CTGF, activation of fibroblasts and their differentiation to myofibroblasts, which secrete and deposit increased amounts of extracellular matrix proteins. These data are concordant with a model wherein repeated cycles of epidermal cell stress, cytokine secretion, dermal inflammation, and profibrotic processes underlie mucocutaneous fibrosis in KS.     

Spectrum of molecular defects and mutation detection rate in patients with mild and moderate hemophilia A

The amount of residual F8 (FVIII:C) determines the clinical severity of hemophilia A. Recently, we showed that the mutation detection rate in severely affected male patients (FVIII:C<1% of normal) is virtually 100% when testing for the common intron 22-/intron 1- inversions and big deletions, followed by genomic sequencing of the F8 gene. Here we report on the spectrum of mutations and their distribution throughout the F8 gene sequence in 135 patients with moderate (n=23) or mild (n=112) hemophilia A. In contrast to the severe form of the disorder, analysis on the genomic level failed to detect the molecular defect in approximately 4% of the moderately and in approximately 12% of the mildly affected patients. A total of 36 of the mutations identified in this study are novel. The vast majority of the detected changes were missense. The newly detected amino acid substitutions were scored for potential distant or local conformational changes and influence on molecular stability for every single F8 domain with available structures, using homology modeling. Two molecular changes in the promoter region of the factor VIII gene (c.-112G>A and -219C>T), affecting the core segment (minimal promoter) were detected in two patients with mild hemophilia A. To our knowledge this is the first report on promoter mutations in the F8 gene.     

Quantitative ultrasonography of facial muscles

Introduction: There is no standardized method for examination of facial muscles with ultrasound. The purpose of this study was to identify those facial muscles accessible for reliable identification and to provide reference data. Methods: In healthy subjects all facial muscles were screened for visibility, separation from adjacent muscles, and reliability of landmarks. Bilateral scans of reliable muscles were performed in 40 adult volunteers. Results: Six facial muscles were clearly demarcated with ultrasound. These were: frontalis, orbicularis oculi, orbicularis oris, depressor anguli oris, depressor labii inferioris, and mentalis muscles. Cross-sectional area and muscle thickness showed gender differences and were independently related to age for some muscles. A significant left–right side difference was only seen for the orbicularis oculi muscle in women. Conclusions: These data demonstrate the usefulness of ultrasonography to assess facial muscles and provide reference values that can be applied in the clinical setting. Muscle Nerve 47: 878–883, 2013     

Extracellular matrix protects pancreatic beta-cells against apoptosis: role of short- and long-term signaling pathways

We have shown previously that culture of beta-cells on matrix derived from 804G cells and rich in laminin-5 improves their function. The purpose of this study was to investigate whether this matrix protects beta-cells against apoptosis and to elucidate signaling pathways involved. Matrix protected sorted rat beta-cells against apoptosis under standard conditions (11.2 mmol/l glucose, 10% serum), after serum deprivation (1% serum), and in response to interleukin-1beta (IL-1beta; 2 ng/ml), compared with control (poly-L-lysine [pLL]). Caspase-8 activity was reduced in cells cultured on matrix, whereas focal adhesion kinase (FAK), protein kinase B (PKB, or Akt), and extracellular signal-regulated kinase (ERK) phosphorylation was augmented. Treatment (4 h) with an anti-beta1 integrin antibody, with the ERK pathway inhibitor PD98059, and/or with the phosphatidylinositol 3-kinase inhibitor LY294002 augmented cell death on 804G matrix but not on pLL. In long-term assays (48 h), PD98059 but not LY294002 drastically augmented cell death on 804G matrix but did so to a lesser extent on pLL. The protein inhibitor of nuclear factor-kappaB (IkappaBalpha) was overexpressed in cells cultured 18 h on matrix with partial blockade by PD98059. In summary, this study provides evidence for activation of signaling pathways and gene expression by extracellular matrix leading to improved beta-cell survival.