Adverse immune reactions prevent clinical translation of numerous implantable devices and materials. Although inflammation is an essential part of tissue regeneration, chronic inflammation ultimately leads to implant failure. In particular, macrophage polarity steers the microenvironment towards inflammation or wound healing via the induction of M1 and M2 macrophages, respectively. Here, we demonstrated that macrophage polarity within biomaterials can be controlled through integrin mediated interactions between human monocytic THP-1 cells and collagen-derived matrix. Surface marker, gene expression, biochemical and cytokine profiling consistently indicated that THP-1 cells within a biomaterial lacking cell attachment motifs yielded pro-inflammatory M1 macrophages, whereas biomaterials with attachment sites in the presence of IL-4 induced an anti-inflammatory M2 like phenotype and propagated the effect of IL-4 in induction of M2 like macrophages. Importantly, integrin α2β1 played a pivotal role as its inhibition blocked the induction of M2 macrophages. The influence of the microenvironment of the biomaterial over macrophage polarity was further confirmed by its ability to modulate the effect of IL-4 and lipopolysaccharide, which are potent inducers of M2 or M1 phenotypes, respectively. Thus, our study represents a novel, versatile and effective strategy to steer macrophage polarity through integrin mediated three-dimensional (3D) microenvironment for biomaterial-based programming.

Hirschsprung's disease (HD) was introduced into the Australian Paediatric Surveillance Unit (APSU) system in 1996 with the objective to collect data on demographics, incidence, family history, associated anomalies, clinical features, investigation, and surgical treatment in Australia. Children under 15 years of age with HD (confirmed by biopsy) were entered into a database maintained at The Children's Hospital at Westmead in Sydney. Nationwide, 127 children with HD were reported from January 1997 to December 2000, and near-complete information was available on 126. Neonatal presentation was seen in 114 cases (90%), whereas 12 (10%) presented post-neonatally. There was a history of delayed passage of meconium (more than 24 h) in 65 of the 114 patients (57%) who presented in the neonatal period. In those presenting post-neonatally there was no history of delayed passage of meconium. Primary pull-through was performed in 42 of the 82 patients (51%) operated upon. The Soave procedure was performed in 53 of the total 82 (65%) operations and 29 of 42(69%) primary pull-through operations. Pre-operative enterocolitis was seen in 15 of 126 (12%) and postoperative enterocolitis in 17 of 82 (21%) children. The majority of children with HD are diagnosed in the neonatal period (90%). Primary pull-through is becoming more popular (51%). The Soave procedure is the most commonly performed operation (65%) in Australia. Pre- and post-operative enterocolitis is still a significant problem.

No abstract

2-(4-Amino-3-methylphenyl) benzothiazole (NSC 674495; DF 203) demonstrates drug uptake and metabolism by tumor cells sensitive to the antiproliferative activity of the drug [J Med Chem 1999;42:4172-4184]. In insensitive cells, little metabolism occurs. Because CYP1A1 can metabolize DF 203, the aryl hydrocarbon receptor (AhR) may mediate drug action. We demonstrate here that DF 203 increases CYP1A1 and CYP1B1 transcription in sensitive MCF-7 cells, accompanied by AhR translocation to the nucleus, increase in xenobiotic-responsive element (XRE)-driven luciferase activity, and induction of protein/DNA complexes on the XRE sequence of the CYP1A1 promoter. MDA-MB-435 and PC3 cells, resistant to DF 203, did not show drug-induced CYP1A1 and CYP1B1 gene expression. AhR was observed to be constitutively localized in the nucleus, with no induction of XRE-driven luciferase activity in transiently transfected cells and weak or no induction of protein/DNA complexes on the XRE sequence of CYP1A1. Taken together, these data elucidate a novel basis for antitumor drug action: induction in sensitive cells of a metabolizing system for the drug itself. These results suggest that clarification of the basis for differential engagement of AhR-related signaling in different tumor cell types may aid in further preclinical development and perhaps early clinical studies.

No abstract

This study suggests patients who present with asymptomatic CCAM will subsequently become symptomatic. Early surgical referral and intervention may be beneficial to avoid the development of complications.

Several oncogenic protein kinases including c-raf-1 and pp60(v-src) are known to directly interact with the 90 kDa heat shock protein (hsp90)/p50 complexes. Using a monoclonal antibody to detect p50 during a purification scheme, p50 was purified to homogeneity. Internal amino acid sequence information was obtained and used to clone a partial cDNA. Comparison of the p50 sequence to other cloned proteins revealed 89% homology with a glycosaminoglycan-binding protein and 54% homology with Drosophila cell cycle control protein (cdc) 37. Monoclonal and polyclonal antibodies were produced against a cleaved fusion protein that recognizes p50 with a high level of specificity. These antibodies recognize the 50 kDa protein present in c-raf-1 and pp60(v-src) complexes. No other proteins were recognized with these antibodies suggesting that p50 is a unique protein. Immunocytochemical visualization of p50 in NIH 3T3 cells indicates a primarily cytoplasmic localization around the nuclear membrane. A survey of p50 expression in murine tissues on a protein blot revealed the following relative levels of expression; thymus > spleen > brain > heart > kidney > liver > lung > skeletal muscle. These results link studies demonstrating complexation of certain kinases with hsp90/p50 in mammalian cells and a number of reports in yeast and Drosophila, demonstrating the importance of cdc37 in cell cycle and kinase function.

No abstract