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Candotti D.,Cambridge Blood Center | Lin C.K.,Red Cross | Belkhiri D.,Cambridge Blood Center | Sakuldamrongpanich T.,Red Cross | And 5 more authors.
Gut | Year: 2012

Objective: To investigate the molecular basis of occult hepatitis B virus (HBV) infection (OBI) in Asian blood donors. Design: OBI donors from Hong Kong, Malaysia, Singapore, Taiwan and Thailand were tested for HBV serological markers, and strains were molecularly characterised. Results: Among 138 confirmed OBI carriers (median age 47 years), HBV genotypes B and C were dominant (60% and 34%, respectively) in agreement with the genotype distribution in chronically infected donors in the region. Viral load ranged between unquantifiable and 3670 IU/ml (median 11 IU/ml). Eleven per cent of OBIs showed an unusual anti-HBs-only serological profile without evidence of past vaccination for most of these individuals. Occult HBV strains showed a higher genetic diversity than strains from matched hepatitis B surface antigen (HBsAg)+ donors, irrespective of genotype. No unique genetic signature or evidence of reduced replication competence was found. Mutations in the vicinity of the pre-S2/S splice donor site were common in OBIB (44%) and OBI C (36%) strains. S regions from four OBI cases were transfected in HuH7 cells. Results showed limited HBsAg secretion and suggested that mutations disrupting the splice donor site structure may affect pre-S2/S mRNA splicing. Conclusions: There is indirect evidence that incomplete immune control is involved in the occurrence of OBI in Asian blood donors infected with genotypes B and C as observed in Europe with genotype A2 but to a lower extent than with genotype D. A post-transcriptional mechanism may play a role in HBsAg expression in some OBIs irrespective of HBV genotype. Source

Tondon R.,Center for Transfusion Medicine | Pandey P.,Sanjay Gandhi Post Graduate Institute of Medical Sciences | Mickey K.B.C.,Center for Transfusion Medicine | Chaudhary R.,Sanjay Gandhi Post Graduate Institute of Medical Sciences
Transfusion and Apheresis Science | Year: 2010

Background: Human errors contribute to one half of all ABO-incompatible transfusions and transfusion-associated fatalities. Material and methods: We report distribution, type and frequency of errors through a prospective study designed specifically to determine errors reported in the cross match lab with their clinical outcome, and to investigate the contributing factors, and underlying system problems. Results: A total of 342 errors (6.2 per 1000 samples) were reported with majority of the errors being clerical (87.1%) and occurred outside the blood bank (86.5%). Labelling errors were the most frequent incidents encountered with bedside being the major site of deviation. The rate of labeling errors was 6.4 errors per 1000 samples (0.64%) in 32,189 samples studied. Among 80,100 components transfused, the frequency of incorrect blood component transfusion (IBCT) was estimated to be 22.5/100,000 blood components transfused. Miscollected samples (WBIT) occurred at a rate of 1 in 1532 samples (0.65 per 1000 samples). More than half of these errors occurred during the day shift (9 errors per 1000 request form) but more with urgent demands (11 errors per 1000 request form). Conclusion: This study indicates the importance of proper specimen labeling and implemented cost-effective, non-compromising policy of rejecting each mislabelled specimen and realises the importance of ongoing quality monitoring to improve laboratory performance. © 2010 Elsevier Ltd. Source

Zurch M.,Friedrich - Schiller University of Jena | Foertsch S.,Siemens AG | Foertsch S.,Friedrich - Alexander - University, Erlangen - Nuremberg | Matzas M.,Siemens AG | And 5 more authors.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2014

In cancer Treatment it is highly desirable To identify and /or classify individual cancer cells in real Time. Nowadays, The standard method is PCR which is costly and Time-consuming. Here we present a different approach To rapidly classify cell Types: we measure The pattern of coherently diffracted extreme ultraviolet radiation (XUV radiation at 38nm wavelength), allowing To distinguish different single breast cancer cell Types. The output of our laser driven XUV light source is focused onto a single unstained and unlabeled cancer cell, and The resulting diffraction pattern is measured in reflection geometry. As we will further show, The outer shape of The object can be retrieved from The diffraction pattern with sub-micron resolution. For classification it is often not necessary To retrieve The image, it is only necessary To compare The diffraction patterns which can be regarded as a spatial fingerprint of The specimen. For a proof-of-principle experiment MCF7 and SKBR3 breast cancer cells were pipetted on gold-coated silica slides. From illuminating each single cell and measuring a diffraction pattern we could distinguish between Them. Owing To The short bursts of coherent soft x-ray light, one could also image Temporal changes of The specimen, i.e. studying changes upon drug application once The desired specimen is found by The classification method. Using a more powerful laser, even classifying circulating Tumor cells (CTC) at a high Throughput seems possible. This lab-sized equipment will allow fast classification of any kind of cells, bacteria or even viruses in The near future. © 2014 SPIE. Source

Sillo F.,University of Turin | Gissi C.,University of Milan | Chignoli D.,University of Turin | Ragni E.,University of Milan | And 3 more authors.
Fungal Genetics and Biology | Year: 2013

The β(1,3)-glucanosyltransferases of the GH72 family are redundant enzymes that are essential for the formation and dynamic remodeling of the fungal wall during different stages of the life cycle. Four putative genes encoding glycosylphosphatidylinositol (GPI)-anchored β(1,3)-glucanosyltransferases, designated TmelGEL1, TmelGEL2, TmelGEL4 and TmelGAS4, have been annotated in the genome of Tuber melanosporum, an ectomycorrhizal fungus that also produces a hypogeous fruiting body (FB) of great commercial value (black truffle). This work focuses on the characterization and expression of this multigene family by taking advantage of a laser microdissection (LMD) technology that has been used to separate two distinct compartments in the FB, the hyphae and the asci containing the ascospores. Of the four genes, TmelGEL1 was the most up-regulated in the FB compared to the free-living mycelium. Inside the FB, the expression of TmelGEL1 was restricted to the hyphal compartment. A phylogenetic analysis of the Gel/Gas protein family of T. melanosporum was also carried out. A total of 237 GH72 proteins from 51 Ascomycotina and 3 Basidiomycota (outgroup) species were analyzed. The resulting tree provides insight into the evolution of the T. melanosporum proteins and identifies new GH72 paralogs/subfamilies. Moreover, it represents a starting point to formulate new hypotheses on the significance of the striking GH72 gene redundancy in fungal biology. © 2013 Elsevier Inc. Source

Ragni E.,Center for Transfusion Medicine | Vigano M.,Center for Transfusion Medicine | Rebulla P.,Center for Transfusion Medicine | Giordano R.,Center for Transfusion Medicine | Lazzari L.,Center for Transfusion Medicine
Journal of Cellular and Molecular Medicine | Year: 2013

In the last years, mesenchymal stem cells (MSCs) have been identified as an attractive cell population in regenerative medicine. In view of future therapeutic applications, the study of specific differentiation-related gene expression is a pivotal prerequisite to define the most appropriate MSC source for clinical translation. In this context, it is crucial to use stable housekeeping genes (HGs) for normalization of qRT-PCR to obtain validated and comparable results. By our knowledge, an exhaustive validation study of HGs comparing MSCs from different sources under various differentiation conditions is still missing. In this pivotal study, we compared the expression levels of 12 genes (ACTB, Β2M, EF1alpha, GAPDH, GUSB, PPIA, RPL13A, RPLP0, TBP, UBC, YWHAZ and 18S rRNA) to assess their suitability as HGs in MSCs during adipogenic, osteogenic and chondrogenic differentiation. We demonstrated that many of the most popular HGs including 18S rRNA, B2M and ACTB were inadequate for normalization, whereas TBP/YWHAZ/GUSB were frequently identified among the best performers. Moreover, we showed the dramatic effects of suboptimal HGs choice on the quantification of cell differentiation markers, thus interfering with a reliable comparison of the lineage potential properties among various MSCs. Thus, in the emerging field of regenerative medicine, the identification of the most appropriate MSC source and cell line is so crucial for the treatment of patients that being inaccurate in the first step of the stem cell characterization can bring important consequences for the patients and for the promising potential of stem cell therapy. © 2012 The Authors. Published by Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd. Source

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