PAX3 in neuroblastoma: oncogenic potential, chemosensitivity and signalling pathways.

Transcription factor PAX3/Pax3 contributes to diverse cell lineages during embryonic development and is important in tumourigenesis. We found that PAX3 is re-expressed in neuroblastoma and malignant neuroblastic (N-type) neuroblastoma cells had significantly higher PAX3 protein expression than their benign substrate-adherent (S-type) counterparts. Knock-down of PAX3 expression by siRNA transfection resulted in persistent cell growth inhibition in both types of neuroblastoma cell, owing to G1 cell cycle arrest and progressive apoptosis. Inhibition of PAX3 expression significantly decreased the attachment of S-type SH-EP1 cells to extra-cellular matrix proteins, fibronectin, laminin and collagen IV. Migration and invasion of both neuroblastoma cell types were markedly reduced after PAX3 down-regulation. PAX3 knock-down significantly augmented the cytotoxic effect of chemotherapeutic agents, etoposide, vincristine and cisplatin, commonly used to treat neuroblastoma. Microarray analyses revealed that particularly signalling pathways involving cell cycle, apoptosis, cell adhesion, cytoskeletal remodelling and development were altered by PAX3 down-regulation. Changes in PAX3 downstream genes identified by microarray analyses were validated in 47 genes by quantitative PCR. These novel findings lead us to propose that PAX3 might contribute to oncogenic characteristics of neuroblastoma cells by regulating a variety of crucial signalling pathways.

Effect of jute yarn on the mechanical behavior of concrete composites.

The objective of the study is to investigate the effect of introducing jute yarn on the mechanical properties of concrete. Jute fibre is produced abundantly in Bangladesh and hence, very cheap. The investigation on the enhancement of mechanical properties of concrete with jute yarn as reinforcement, if enhanced, will not only explore a way to improve the properties of concrete, it will also explore the use of jute and restrict the utilization of polymer which is environmentally detrimental. To accomplish the objective, an experimental investigation of the compressive, flexural and tensile strengths of Jute Yarn Reinforced Concrete composites (JYRCC) has been conducted. Cylinders, prisms and cubes of standard dimensions have been made to introducing jute yarn varying the mix ratio of the ingredients in concrete, water cement ratio, length and volume of yarn to know the effect of parameters as mentioned. Compressive, flexural and tensile strength tests had been conducted on the prepared samples by appropriate testing apparatus following Standards of tests. Mechanical properties of JYRCC were observed to be enhanced for a particular range of lengths of cut (10, 15, 20 and 25 mm) and volume content of jute yarn (0.1, 0.25, 0.5 and 0.75 %). The maximum increment of compressive, flexural and tensile strengths observed in the investigation are 33, 23 and 38 %, respectively with respect to concrete without jute yarn.