Management of ligneous conjunctivitis in a child with plasminogen deficiency

Plasminogen deficiency, a rare autosomal recessive disorder, is classified as type I (hypoplasminogenemia) or type II (dysplasminogenemia). Hypoplasminogenemia is characterized by impaired wound healing while ligneous conjunctivitis (LC) is its main manifestation presenting with redness of the conjunctivae and progression to pseudomembranes' formation on the palpebral surfaces. A 4-year-old girl with LC in her left eye and impaired vision was referred to our unit. The conjunctival membranes had been already excised twice, followed by recurrences. Soon after the third recurrence, a probable diagnosis of LC was suggested, confirmed by a reduced plasminogen activity at 20% (normal values 80-120%). Both of her parents have slightly reduced plasminogen levels (50-60%) without any relevant symptom. Fresh frozen plasma (FFP) was administered systemically and topically, initiating 2 days before surgical removal of pseudomembranes with electrocautery under general anaesthesia. Systemic FFP was administered for 12 days postoperatively, along with topical use; the later was continued thereafter for 3 months. No recurrence was noticed. The vision was improved. Two weeks after cessation of the topical treatment, pseudomembranes reappeared. Topical application of FFP was reinitiated soon thereafter, and the girl underwent a second operation to have the conjunctival pseudomembranes removed. The perioperative therapeutic management was as previously described. Systemic treatment was stopped at the end of the tenth day while topical application of FFP was being continued until now, 10 months postoperatively. No recurrence has been observed and the vision remains at 9/10. Conclusion: Since surgical excision of the conjunctival pseudomembranes alone in patients with LC does not protect from recurrences, the perioperative administration of FFP, both systemically and topically improves the outcome. Furthermore, the long-term application of topical FFP preparations seems to prevent recurrences and has a protective effect on the vision of these patients.     

Cell specific-chondroitin sulfate proteoglycan expression during CNS morphogenesis in the chick embryo

There is increasing evidence that proteoglycans, particularly chondroitin sulfate proteoglycans (CSPGs), are integral components in the assembly of the extracellular matrix during early stages of histogenesis. The differential expression of several CSPGs in the developing CNS has raised questions on their origin, phenotype (chemical and structural characteristics), regulation of expression and function. The S103L monoclonal antibody has been an invaluable specific reagent to identify and study a large and abundant CSPG in embryonic chick brain. In the present study we demonstrate that during embryogenesis of the chick CNS, the S103L CSPG (B-aggrecan) is synthesized by neurons of all major neuronal cell types but not by astrocytes, is developmentally regulated, and is associated predominantly with neuronal somata, suggesting that neuronal-specific regulatory mechanisms control the expression of the S103L CSPG in culture. Neurons also exhibit differential expression of glycosaminoglycan type (i.e., KS) and sulfation patterns on different CSPGs when compared to astrocytes, meningial cells or chondrocytes, implying the existence of additional, cell type-specific modes of regulation of the final CSPG phenotype (chemical and structural posttranslational characteristics). A specific temporal pattern of expression of the S103L-CSPG was observed which may contribute to conditions that induce or stabilize specific cell phenotypes during CNS development. In contrast, the other major CSPG in the CNS recognized by the HNK-1 antibody, is synthesized by all cell types of different cell lineages over the entire embryonic period, suggesting a more global cell maintenance function for this CSPG.     

Kallikrein-related peptidase-6 (KLK6) mRNA expression is an independent prognostic tissue biomarker of poor disease-free and overall survival in colorectal adenocarcinoma

Members of the family of tissue kallikrein and kallikrein-related peptidases possess important prognostic value in cancer. Moreover, the oncogenic role of kallikrein-related peptidase-6 (KLK6) in colorectal cancer has been well documented so far. This study investigated the prognostic value of KLK6 mRNA expression as a molecular tissue biomarker in colorectal adenocarcinoma. For this purpose, KLK6 mRNA expression was studied in 110 primary colorectal adenocarcinomas and 39 paired noncancerous colorectal specimens. A dramatic upregulation of KLK6 mRNA expression was observed in colorectal tumors. KLK6 mRNA overexpression was associated with high depth of tumor invasion, presence of distant metastases, and tumor-node-metastasis (TNM) stage of patients. Furthermore, KLK6 mRNA expression was shown to predict poor disease-free and overall survival independently of patient gender, age, tumor size, location, histological subtype, grade, venous invasion, lymphatic invasion, TNM stage, radiotherapy, and chemotherapy treatment. Moreover, Kaplan–Meier survival analysis revealed that colorectal adenocarcinoma patients with negative regional lymph nodes (N0) and those without distant metastases (M0) harboring KLK6 mRNA-positive colorectal tumors tended to relapse and die earlier than N0 and M0 patients with KLK6 mRNA-negative colorectal adenocarcinoma. Thus, KLK6 mRNA expression could be considered as an independent, unfavorable molecular prognostic biomarker in colorectal adenocarcinoma, with additional prognostic value in patients without regional or distant metastases.     

Α-aryl-N-alkyl nitrones, as potential agents for stroke treatment: synthesis, theoretical calculations, antioxidant, anti-inflammatory, neuroprotective, and brain-blood barrier permeability properties

We report the synthesis, theoretical calculations, the antioxidant, anti-inflammatory, and neuroprotective properties, and the ability to cross the blood-brain barrier (BBB) of (Z)-α-aryl and heteroaryl-N-alkyl nitrones as potential agents for stroke treatment. The majority of nitrones compete with DMSO for hydroxyl radicals, and most of them are potent lipoxygenase inhibitors. Cell viability-related (MTT assay) studies clearly showed that nitrones 1-3 and 10 give rise to significant neuroprotection. When compounds 1-11 were tested for necrotic cell death (LDH release test) nitrones 1-3, 6, 7, and 9 proved to be neuroprotective agents. In vitro evaluation of the BBB penetration of selected nitrones 1, 2, 10, and 11 using the PAMPA-BBB assay showed that all of them cross the BBB. Permeable quinoline nitrones 2 and 3 show potent combined antioxidant and neuroprotective properties and, therefore, can be considered as new lead compounds for further development in specific tests for potential stroke treatment.     

B cell priming for extrafollicular antibody responses requires Bcl-6 expression by T cells

T follicular helper cells (Tfh cells) localize to follicles where they provide growth and selection signals to mutated germinal center (GC) B cells, thus promoting their differentiation into high affinity long-lived plasma cells and memory B cells. T-dependent B cell differentiation also occurs extrafollicularly, giving rise to unmutated plasma cells that are important for early protection against microbial infections. Bcl-6 expression in T cells has been shown to be essential for the formation of Tfh cells and GC B cells, but little is known about its requirement in physiological extrafollicular antibody responses. We use several mouse models in which extrafollicular plasma cells can be unequivocally distinguished from those of GC origin, combined with antigen-specific T and B cells, to show that the absence of T cell-expressed Bcl-6 significantly reduces T-dependent extrafollicular antibody responses. Bcl-6(+) T cells appear at the T-B border soon after T cell priming and before GC formation, and these cells express low amounts of PD-1. Their appearance precedes that of Bcl-6(+) PD-1(hi) T cells, which are found within the GC. IL-21 acts early to promote both follicular and extrafollicular antibody responses. In conclusion, Bcl-6(+) T cells are necessary at B cell priming to form extrafollicular antibody responses, and these pre-GC Tfh cells can be distinguished phenotypically from GC Tfh cells.     

Expression analysis and clinical evaluation of kallikrein-related peptidase 10 (<Emphasis Type="Italic">KLK10</Emphasis>) in colorectal cancer

Kallikrein-related peptidases (KLKs) represent a serine protease family having 15 members. KLK10 is a secreted protease with a trypsin-like activity. The function of KLK10 is poorly understood, although it has been suggested that KLK10 may function as a tumor suppressor gene. In human cancer, KLK10 gene shows organ-specific up- or down-regulation. Since KLKs are promising tumor biomarkers, the examination of KLK10 mRNA expression and its association with colorectal cancer (CRC) progression was studied using semi-quantitative PCR. One hundred and nineteen primary CRC specimens were examined for which follow-up information was available for a median period of 29 months (range, 1–104 months). KLK10 expression was found to be significantly associated with TNM stage (p = 0.028). Cox proportional hazard regression model using univariate analysis revealed for the first time that high status KLK10 expression is a significant factor for disease-free survival (DFS; p = 0.002) and overall survival (OS; p = 0.026) of patients. Kaplan–Meier survival curves demonstrated that KLK10 expression of low status is significantly associated with longer DFS (p = 0.001) as well as OS (p = 0.021), suggesting that KLK10 gene expression may be used as a marker of unfavorable prognosis for CRC. As the epigenetics of cancer are unraveled, KLK10 may represent not only a novel biomarker, but also a promising future therapeutic target for the disease.     

Integrin α3 mutations with kidney, lung, and skin disease

Integrin α(3) is a transmembrane integrin receptor subunit that mediates signals between the cells and their microenvironment. We identified three patients with homozygous mutations in the integrin α(3) gene that were associated with disrupted basement-membrane structures and compromised barrier functions in kidney, lung, and skin. The patients had a multiorgan disorder that included congenital nephrotic syndrome, interstitial lung disease, and epidermolysis bullosa. The renal and respiratory features predominated, and the lung involvement accounted for the lethal course of the disease. Although skin fragility was mild, it provided clues to the diagnosis.