Early warning tools for ecotoxicity assessment based on Phaeodactylum tricornutum

Phaeodactylum tricornutum was exposed to various toxic substances (zinc, copper or dodecylbenzenesulfonic acid sodium salt) in accordance with the AlgalToxkit^® protocol based on the UNI EN ISO 10253 method in order to quantitatively compare the responses obtained by traditional growth-rate inhibition tests with morphological (biovolume) and physiological (chlorophyll-a, phaeophytin ratio) endpoints. A novel approach is proposed for detecting early and sub-lethal effects based on biovolume quantification using confocal microscopy coupled with an image analysis system. The results showed that effects on both biovolume and the photosynthetic complex are sensitive and powerful early warning tools for evaluating sub-lethal effects of exposure. Specifically, biovolume showed significant sensitive and early responses for the tested surfactant. Qualitatively, we also observed structural anomalies and effects on natural auto-fluorescence in exposed cells that also represent potentially useful tools for ecotoxicological studies.     

Facial animation in children with Moebius and Moebius-like syndromes

Background

Moebius syndrome, a rare congenital disorder of varying severity, involves multiple cranial nerves and is characterized predominantly by bilateral or unilateral paralysis of the facial and abducens nerves. The paralysis of the VI and VII cranial nerves leads to a lack of function in the muscles they supply. Facial paralysis often causes bilabial incompetence with speech difficulties, oral incompetence, problems with eating and drinking, including pocketing of food in the cheek and dribbling, as well as severe drooling.

Methods

In this study, we report on pediatric patients with Moebius and Moebius-like syndromes seen and treated surgically from 2003 to September 2007 at the Operative Unit of Maxillofacial Surgery, Head and Neck Department, University of Parma, Italy.

Results

Twelve patients underwent microsurgical reconstruction for restoration of facial movement. The contralateral facial nerve was used as a motor donor nerve in 4 procedures, the motor nerve to the masseter muscle was used in 8 patients, and the gracilis muscle was used in all operations, with a total of 17 free-muscle transplantations. All free-muscle transplantations survived transfer, and no flap was lost. We observed a significant improvement in drooling, drinking, speech, and facial animation with a high degree of patient satisfaction.

Conclusions

The gracilis muscle free transfer is a surgical procedure well tolerated by the young patients and well accepted by their families. We consider it a safe and reliable technique for facial reanimation with good aesthetical and functional results in children with Moebius and Moebius-like syndromes.     

Receptor-type protein tyrosine phosphatase gamma (PTPgamma), a new identifier for myeloid dendritic cells and specialized macrophages

Protein tyrosine phosphatase (PTPgamma) is a receptor-like molecule with a known role in murine hematopoiesis. We analyzed the regulation of PTPgamma expression in the human hematopoietic system, where it was detected in human peripheral blood monocytes and dendritic cells (DCs) of myeloid and plasmacytoid phenotypes. Its expression was maintained during in vitro monocyte differentiation to dendritic cells (moDC) and was further increased after maturation with bacterial lipopolysaccharide (LPS), CD40L, and TNFalpha. But PTPgamma was absent when monocytes from the same donor were induced to differentiate in macrophages. B and T lymphocytes did not express PTPgamma. Rather, PTPgamma mRNA was expressed in primary and secondary lymphoid tissues, and the highest expression was in the spleen. PTPgamma was detected by immunohistochemistry in subsets of myeloid-derived DCs and specialized macrophages (tingible bodies, sinus and alveolar macrophages). Classic macrophages in infective or reactive granulomatous reactions did not express PTPgamma. Increased PTPgamma expression was associated with a decreased ability to induce proliferation and interferon-gamma secretion in T cells by moDCs from patients with advanced pancreatic cancer. Taken together, these results indicate that PTPgamma is a finely regulated protein in DC and macrophage subsets in vitro and in vivo.     

Heterozygous beta-globin gene mutations as a risk factor for iron accumulation and liver fibrosis in chronic hepatitis C

BACKGROUND: Iron accumulation is a well-known risk factor for the progression of chronic hepatitis C (CHC) to fibrosis. However, the profibrogenic role of the genes controlling iron homeostasis is still controversial. AIM: To evaluate the relative role of haemachromatosis (HFE), ferroportin and beta-globin gene mutations in promoting iron accumulation and fibrosis in patients with CHC. METHODS: Genetic analysis was performed together with the assessment of hepatic iron content and histology in 100 consecutive HIV-antibody and hepatitis B surface antigen-negative patients with biopsy-proven CHC. RESULTS: Among the patients investigated, 12 were heterozygous for various beta-globin gene mutations (39[C-->T], IVS1.1[G-->A], 22 7 bp deletion and IVS1.6[T-->C]) and 29 carried HFE (C282Y, H63D and S65C) gene mutations. One further patient was heterozygous for both HFE (H63D) and beta-globin (39[C-->T]) variants, whereas 58 had the wild-type alleles of both the genes. Hepatic iron concentration (HIC) and hepatic stainable iron were significantly higher (p<0.05) in patients with CHC carrying beta-globin mutations than in those with HFE mutations or the wild-type alleles. Multivariate analysis confirmed that the presence of beta-globin mutations was independently associated with both HIC (p = 0.008) and hepatic-stainable iron (odds ratio (OR) 6.11; 95% CI 1.56 to 23.92; p = 0.009). Moderate/severe fibrosis or cirrhosis (Ishak's score >2) was observed in 48 of 100 patients. Logistic regression demonstrated that age (OR 1.05; 95% CI 1.02 to 1.09; p<0.005) and beta-globin mutations (OR 4.99; 95% CI 1.22 to 20.3; p = 0.025) were independent predictors of the severity of fibrosis. CONCLUSIONS: Heterozygosis for beta-globin mutations is a novel risk factor for both hepatic iron accumulation and the progression to fibrosis in patients with CHC.     

The role of chemerin in the colocalization of NK and dendritic cell subsets into inflamed tissues

Chemerin is a chemotactic agonist recently identified as the ligand of ChemR23, a serpentine receptor expressed by mononuclear phagocytes and dendritic cells (DCs). This study shows that blood CD56(low)CD16(+) natural killer (NK) cells selectively express functional ChemR23 and that this receptor is coexpressed with CXCR1, the CXCL8 receptor, and the KIR receptors. In vitro culturing of NK cells with IL-2 or IL-15 induced a delayed and time-dependent down-regulation of ChemR23 that was associated with the inhibition of NK cell migration to chemerin. Biopsies obtained from patients with oral lichen planus presented an infiltration of CD94(+)CD3(-)CD56(+) NK cells that coexpressed ChemR23. The same biopsies were infiltrated by myeloid, DC-SIGN(+) and plasmacytoid, CD123(+)BDCA2(+), ChemR23(+) dendritic cells that were occasionally associated with NK cells. In the same histologic sections, chemerin was expressed by inflamed dermal endothelium. These findings propose a role for the ChemR23/chemerin axis in the recruitment of blood NK cells and strongly implicate chemerin as a key factor for the colocalization of NK cells and DC subsets in pathologic peripheral tissues.     

Regulation of dendritic cell migration and adaptive immune response by leukotriene B4 receptors: a role for LTB4 in up-regulation of CCR7 expression and function

Trafficking of dendritic cells (DCs) to peripheral tissues and to secondary lymphoid organs depends on chemokines and lipid mediators. Here, we show that bone marrow-derived DCs (BM-DCs) express functional leukotriene B4 (LTB4) receptors as observed in dose-dependent chemotaxis and calcium mobilization responses. LTB4, at low concentrations, promoted the migration of immature and mature DCs to CCL19 and CCL21, which was associated with a rapid (30-minute) increase of CCR7 expression at the membrane level. At longer incubation times (6 hours), gene array analysis revealed a promoting role of LTB4, showing a significant increase of CCR7 and CCL19 mRNA levels. BM-DCs cultured from BLT1-/- or BLT1/2-/- mice showed a normal phenotype, but in vivo BLT1/2-/-DCs showed dramatic decrease in migration to the draining lymph nodes relative to wild-type (WT) DCs. Consistent with these observations, BLT1/2-/- mice showed a reduced response in a model of 2,4-dinitro-fluorobenzene (DNFB)-induced contact hypersensitivity. Adoptive transfer of 2,4-dinitrobenzene sulfonic acid (DNBS)-pulsed DCs directly implicated the defect in DC migration to lymph node with the defect in contact hypersensitivity. These results provide strong evidence for a role of LTB4 in regulating DC migration and the induction of adaptive immune responses.     

Current insights in renal cell cancer pathology

In recent years molecular biologists and pathologists have described new entities of renal cell cancer (RCC) with a totally different morphology and biology among the histotypes of renal carcinoma, but always referring to the same renal cancer disease. The evidence of a distinct biological behavior and long-term prognosis among these makes the correct pathological diagnosis of renal cancer critically important for the clinician. Advances in understanding of the pathogenesis, behavior, and importance of prognostic factors for RCC have paved the way for a revision of its classification and staging. We reviewed the role of histological classification, microscopic tumor necrosis, microscopic venous invasion, lymph node involvement and, particularly, pathological stage. In our series of patients who underwent renal surgery for neoplasm, a retrospective study established the predictive role of tumor size on recurrence rate, compared with other known prognostic factors, and we conclude that histological grade, pathological stage and tumor size remain relevant prognosticators in early stage RCC patients. In order to optimize the management of patients with RCC it is necessary to develop an interdisciplinary approach (surgeon, radiologist, pathologist, oncologist) and find new prognostic parameters at molecular and cellular levels. Many efforts are ongoing to integrate molecular data (from tissue microarrays) and clinical data (traditional prognosticators) into a molecular integrated staging system. In the postgenomic era, new tumor-associated antigens and molecules can be identified at the protein level using proteomics, providing a major opportunity for screening and finding novel targets that are the basis of new emerging therapies for RCC.