Effects of high Zn and Pb concentrations on Phragmites australis (Cav.) Trin. Ex. Steudel: Photosynthetic performance and metal accumulation capacity under controlled conditions.

The response of Phragmites australis (Cav.) Trin. Ex. Steudel to zinc (Zn) and lead (Pb) was studied separately in two hydroponic tests, during a three weeks experiment. The effects on ecophysiology and biomass partitioning were evaluated during the metal treatments and at the recovery, and total metal content and accumulation capacity in different plant organs were assessed. Zn and Pb had different effects on the overall measured parameters, highlighting different mechanism of action. In particular, Zn concentration was higher in roots and, being a micronutrient, it was translocated into leaves, producing a reduction of assimilation rate, stomatal conductance (-71.9 and -81.3% respect to the control plant respectively), and a strong down regulation of photosystems functionality both at PSII and PSI level. Otherwise, Pb was accumulated mainly in the more lignified tissue such as rhizomes, with slightly effect on gas exchange. Chlorophyll a fluorescence highlighted that Pb inhibits the electron transfer process at the PSI donor side, without recovery after the removal of the metal stress. Despite these physiological limitations, P. australis showed a high capacity to accumulate both metals, and only slight reduction of biomass, being therefore a suitable species for phytoremediation interventions.

Application of a protocol for the diagnosis of postweaning multisystemic wasting syndrome in Italy.

Samples of superficial inguinal and bronchial lymph nodes, ileum, tonsil and lung were taken from three to five pigs on each of 61 farms with a clinical history of postweaning multisystemic wasting syndrome (PMWS). The samples were examined histologically and by immunohistochemistry for porcine circovirus type 2 (PCV-2). PMWS was diagnosed in two stages: first, an evaluation of the haematoxylin and eosin-stained sections that identified the cases in which the characteristic PCV-2 cytoplasmic inclusion bodies were apparent, and secondly, a conclusive step in which immunohistochemistry was applied to confirm PMWS in the cases in which there were positive immunohistochemical results that coincided with lesions indicative of PMWS in at least one of the lymphoid and/or lung tissues. The location of PCV-2 in specific lesions (cell depletion in lymphoid organs and interstitial pneumonia) confirmed PMWS in 45 of the 61 farms, 31 of which were also infected with porcine reproductive and respiratory syndrome virus. The lymphoid tissues were more reliable than the lungs for the diagnosis of PMWS, both in individual pigs and in groups of pigs, and farm diagnoses based on a group of pigs were more reliable than diagnoses based on single pigs.

X-ray scanning microscopies of microcalcifications in abdominal aortic and popliteal artery aneurysms.

Abdominal aortic and popliteal artery aneurysms are vascular diseases which show massive degeneration, weakening of the vascular wall and loss of the vascular tissue functionality. They are driven by inflammatory, hemodynamical factors and biological alterations that may lead, in the case of an abdominal aortic aneurysm, to sudden and dangerous ruptures of the arteries. Here, human aortic and popliteal aneurysm tissues were obtained during surgical repair, and studied by synchrotron radiation X-ray scanning microdiffraction and small-angle scattering, to investigate the microcalcifications present in the tissues. Data collected during the experiments were transformed into quantitative microscopy images through the combination of statistical approaches and crystallographic methods. As a result of this multi-step analysis, microcalcifications, which are markers of the pathology, were classified in terms of chemical and structural content. This analysis helped to identify the presence of nanocrystalline hy-droxy-apatite and microcrystalline cholesterol, embedded in myofilament, and elastin-containing tissue with low collagen content in predominantly nanocrystalline areas. The generality of the approach allows it to be transferred to other types of tissue and other pathologies affected by microcalcifications, such as thyroid carcinoma, breast cancer, testicular microli-thia-sis or glioblastoma.

Early and late adjustments of the photosynthetic traits and stomatal density in Quercus ilex L. grown in an ozone-enriched environment.

Quercus ilex L. seedlings were exposed in open-top chambers for one growing season to three levels of ozone (O3 ): charcoal filtered air, non-filtered air supplemented with +30% or +74% ambient air O3 . Key functional parameters related to photosynthetic performance and stomatal density were measured to evaluate the response mechanisms of Q. ilex to chronic O3 exposure, clarifying how ecophysiological traits are modulated during the season in an ozone-enriched environment. Dark respiration showed an early response to O3 exposure, increasing approximately 45% relative to charcoal-filtered air in both O3 enriched treatments. However, at the end of the growing season, maximum rate of assimilation (Amax ) and stomatal conductance (gs ) showed a decline (-13% and -36%, for Amax and gs , respectively) only in plants under higher O3 levels. Photosystem I functionality supported the capacity of Q. ilex to cope with oxidative stress by adjusting the energy flow partitioning inside the photosystems. The response to O3 was also characterised by increased stomatal density in both O3 enriched treatments relative to controls. Our results suggest that in order to improve the reliability of metrics for O3 risk assessment, the seasonal changes in the response of gs and photosynthetic machinery to O3 stress should be considered.

Familial pancreatic cancer: a review.

The cause of pancreatic cancer remains elusive. The most consistently identified epidemiological risk factor is cigarette smoking. Genetic factors are known to play a significant role in perhaps 5% of the total pancreatic cancer burden. Recent discoveries in molecular biology, particularly germline mutations in inherited conditions which feature pancreatic cancer as an integral part of the tumor spectrum such as in adenomatosis polyposis and hereditary nonpolyposis colorectal cancer, provide powerful incentive to search for other "cancer genes" in this heterogeneous disease. Early detection of this dreadful disease is crucial because its mortality rate approximates its incidence; the ability to identify high-risk patients on the basis of genetic analysis would significantly enhance the potential for early diagnosis. This review addresses the genetic epidemiology of pancreatic cancer and updates our views on screening, surgery, chemotherapy, and genetic counseling, all of which must be used to gain value from genetic predictability of risk status.

Genomic sequencing of DPC4 in the analysis of familial pancreatic carcinoma.

A first-degree relative with pancreatic cancer is found in 5% to 10% of patients with pancreatic carcinomas, suggesting an inherited predisposition for this neoplasm. The recently identified DPC4 tumor suppressor gene is a strong candidate for the gene responsible for the familial form of pancreatic carcinoma. DPC4 was identified in a consensus area of homozygous deletion in pancreatic carcinomas, and it is biallelically inactivated in approximately 50% of sporadic pancreatic carcinomas. The coding sequence of this gene is 1660 nucleotides in length, covering 11 exons. We describe optimized primers and conditions used in polymerase chain reaction and cycle sequencing of the entire DPC4 coding sequence of 25 individuals (eight with pancreatic carcinoma) from 11 kindreds with a familial aggregation of pancreatic carcinoma. No mutations in the coding sequences of the DPC4 gene were found; hence, it appears that germline mutations in DPC4 cannot account for many of the familial aggregations of pancreatic carcinoma.

Familial pancreatic cancer: a family study.

The etiology of pancreatic cancer remains elusive. Recent attention has been given to host factors, as evidenced by the recognition of familial aggregations of this disease and its association with several hereditary cancer-prone disorders. We have investigated a remarkable family wherein pancreatic cancer has been documented through three generations, including progeny from two of the progenitor's three marriages. The protocol involved a search for documentation of cancer of all anatomic sites. We did not find any pattern of extrapancreatic cancer occurrences, and age at onset of pancreatic cancer corresponded to population expectations. The recognition of patients at high risk for pancreatic cancer should lead to research into potential environmental factors interacting with host susceptibility for elucidation of etiology and for earlier diagnosis.

Poly-L-lactide acid-modified scaffolds for osteoinduction and osteoconduction.

Poly-L-lactide acid (PLLA) scaffold has been modified to enhance its osteoconductive and osteoinductive properties in view of a bone tissue engineering application. Two approaches have been followed: (i) coating with laminin or fibronectin and (ii) grafting with arginine-glycine-aspatic acid (RGD) or SIKVAV peptides. Moreover we have added a bioactive molecule 1,25-(OH)2 D3 into the scaffold that shows better cellular interaction to implement osteoinduction and osteogenesis. The two coatings promoted only cell adhesion in the very short term while even if grafted scaffolds had cell seeding efficiency similar to ungrafted PLLA, the grafted ones supported better the proliferation of seeded human osteoblast (hOB) and human mesenchymal stem cells (hMSCs) over 1 week of culture. Our data showed that in view of bone integration and bone regeneration, PLLA grafting with RGD can be considered a good substrate to induce hOB adhesion and proliferation but having no significant effect on the osteogenic induction, the scaffold has to be reinforced with osteoinductive molecules. It can be concluded from reverse transcriptase polymerase chain reaction results, alkaline phosphatase activity and mineralization assays that 1,25(OH)2 D3 reinforced RGD-PLLA keeps increased cell proliferation supported by an upregulation of the studied osteogenic markers and induced hMSCs differentiation into osteoblasts demonstrating osteoinductivity and osteoconductivity of the new formulated scaffold. These results can lead to a future application of RGD-D3-PLLA as an osteogenic material for bone replacement..

The biological response of poly(L-lactide) films modified by different biomolecules: role of the coating strategy.

The interactions between the surface of synthetic scaffolds and cells play an important role in tissue engineering applications. To improve these interactions, two strategies are generally followed: surface coating with large proteins and surface grafting with small peptides. The proteins and peptides more often used and derived from the extracellular matrix, are fibronectin, laminin, and their active peptides, RGD and SIKVAV, respectively. The aim of this work was to compare the effects of coating and grafting of poly(L-lactide) (PLLA) films on MRC5 fibroblast cells. Grafting reactions were verified by X-ray photoelectron spectroscopy. Cell adhesion and proliferation on coated and grafted PLLA surfaces were measured by cell counting. Vinculin localization and distribution were performed on cell cultured on PLLA samples using a fluorescence microscopy technique. Finally, western blot was performed to compare signals of cell adhesion proteins, such as vinculin, Rac1, and RhoA, as well as cell proliferation, such as PCNA. These tests showed similar results for fibronectin and laminin coated PLLA, while RGD grafting is more effective compared with SIKVAV grafting. Considering the overall view of these results, although coating and grafting can both be regarded as effective methods for surface modification to enhance cell adhesion and proliferation on a biomaterial, RGD grafted PLLA show better cell adhesion and proliferation than coated PLLA, while SIKVAV grafted PLLA show similar adhesion but worse proliferation. These data verified different biological effects depending on the surface modification method used.

Immunohistochemical detection of aetiological agents of proliferative and necrotizing pneumonia in italian pigs.

Proliferative and necrotizing pneumonia (PNP) is a form of interstitial pneumonia that occurs in weaning and post-weaning pigs. PNP is characterized by hypertrophy and hyperplasia of type II pneumocytes and coagulative necrosis and granular debris within alveolar spaces. Canadian and European studies suggest that the porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) are the main causes of the disease, but Aujezsky's disease virus (ADV) and swine influenza virus (SIV) have also been considered as potential aetiological agents. An immunohistochemical study was carried out on the lungs of 28 Italian pigs with PNP in order to evaluate the role of PRRSV, PCV2 and ADV in PNP lesions. PRRSV infection was identified in the lungs of 11 pigs, PCV2 in the lungs of four pigs and coinfection with both viruses in the lungs of eight pigs. Neither virus was detected in the lungs of the remaining five pigs. ADV antigen was not detected in any sample. The principle aetiological agent of PNP in Italy therefore appears to be PRRSV. Coinfection with PRRSV and PCV2 is characterized by more severe microscopical changes in affected lungs.

Aloe-Emodin quinone pretreatment reduces acute liver injury induced by carbon tetrachloride.

Aloe contains several active compounds including aloin, a C-glycoside that can be hydrolyzed in the gut to form aloe-emodin anthrone which, in turn, is auto-oxidized to the quinone aloe-emodin. On the basis of the claimed hepatoprotective activity of some antraquinones, we studied aloe-emodin in a rat model of carbon tetrachloride (CCl4) intoxication, since this xenobiotic induces acute liver damage by lipid peroxidation subsequent to free radical production. Twelve rats were treated with CCl4 (3 mg/kg) intraperitoneally and six were protected with two intraperitoneally injections of aloe-emodin (50 mg/kg; CCl4+aloe-emodin); six other rats were only aloe-emodin injected (aloe-emodin) and six were untreated (control). Histological examination of the livers showed less marked lesions in the CCl4+aloe-emodin rats than in those treated with CCl4 alone, and this was confirmed by the serum levels of L-aspartate-2-oxoglutate-aminotransferase (394+/-38.6 UI/l in CCl4, 280+/-24.47 UI/l in CCl4+aloe-emodin rats; P<0.05). We also quantified changes in hepatic albumin and tumour necrosis factor-alpha mRNAs. Albumin mRNA expression was significantly lower only in the liver of CCl4 rats (P<0.05 versus control) and was only slightly reduced in the CCl4+aloe-emodin rats. In contrast tumour necrosis factor-alpha mRNA was significantly higher (P<0.05) in the CCl4 than the control rats and almost equal in the CCl4+aloe-emodin, aloe-emodin and control groups. In conclusion, aloe-emodin appears to have some protective effect not only against hepatocyte death but also on the inflammatory response subsequent to lipid peroxidation.

Novel germline p16(INK4) allele (Asp145Cys) in a family with multiple pancreatic carcinomas. Mutations in brief no. 148. Online.

As part of a search for causative genes of familial pancreatic carcinoma, the p16 genes were sequenced in members of 21 families with a phenotype of familial pancreatic carcinoma (2 or more first degree relatives affected). One family was found in which members carried a novel p16 allele with a G to T transversion at position 451, creating a missense amino acid change at codon 145 (Asp to Cys) and possibly disrupting the donor splice site of the exon 2/3 boundary. This coding change is not a known polymorphism, and occurs at a codon position in which another missese/splicing change has been shown to be linked to familial melanoma/pancreas cancer.