Poly(lactic acid) (PLA)‐block‐poly(norbornene) (PNB) copolymers which bear photocrosslinkable cinnamate side‐chains are synthesized by combining the ring‐opening metathesis polymerization (ROMP) of norbornenes with the ring‐opening polymerization (ROP) of lactides. Highly porous 3D scaffolds with tunable pore sizes ranging from 20 to 300 µm are fabricated through liquid–solid phase separation. Scaffolds with an average pore size around 250 µm, which are under investigation as bone grafting materials, are reproducibly obtained from freeze‐drying 5% w/v benzene solutions of PLA‐b‐PNB copolymers at −10 °C. As a demonstration of the impact of photocrosslinking of cinnamate side‐chains, scaffolds are exposed to UV radiation for 8 h, resulting in a 33% increase in the compressive modulus of the polymeric scaffold. The foams and the methodology described herein represent a new strategy toward polymeric scaffolds with potential for use in regenerative medicine applications.

No abstract

No abstract

No abstract

Analysis of the expression of hsp70 (70 kDa heat-shock proteins) in normal and pathological tissues might prove their potential diagnostic and prognostic values. In the present study, we combined high-resolution two-dimensional polyacrylamide gel electrophoresis with immunoblotting to study hsp70 expression in normal, preneoplastic and neoplastic colonic mucosa. By monoclonal anti-hsp70 antibody, recognizing both the constitutive and inducible forms of hsp70, we have detected six charge isoforms localized in the pH 5.1-5.3 range and in the molecular mass range of 68-69 kDa in normal colonic mucosa. Immunostaining of hsp70 in polypous and malignant tissues revealed qualitative as well as quantitative changes in the expression of more acidic isoforms of hsp70 in comparison with normal tissue. Furthermore, the different basic isoforms of hsp70 were detected in chronically inflamed colonic mucosa from patients suffering from ulcerative colitis (UC) or Crohn's disease (CD). Besides the standard hsp70 protein pattern, additional proteins with molecular masses of about 39, 40, 74 and 75 kDa were variably immunostained in normal and pathological specimens. These observations suggest that hsp70 expression may be closely linked to disease etiology and/or pathophysiology.