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Chemotherapy might damage intestinal barrier function (IBF). The aim of the study was to evaluate the effect of dietary fiber on IBF of 5-fluorouracil (5-Fu) stressed rats. Thirty Wistar rats after gastrostomy were assigned randomly to one of three groups (10 of each group), Chow, enteral nutrition (EN), or EN+Fiber (2 g/100 ml solution). They kept their diets respectively for 8 days. 5-Fu (75 mg/kg body weight) was injected intraperitoneally on day 4. Urinary recovery ratios of lactulose and mannitol (L%/M%) were measured on day 3 and day 7. The mesenteric lymph nodes were harvested for bacterial translocation (BT). On day 8, small intestine and colon were taken for wet weight, mucosal thickness of both small intestine and colon and villus height of small intestine. The BT rates of Chow and EN+Fiber groups (20% for both) were lower than that of EN group (70%) (P<0.05). The L%/M% of both EN+Fiber (from 0.0265+/-0.0073 to 0.0274+/-0.0068) and Chow groups (from 0.0268+/-0.0039 to 0.0281+/-0. 0044) were unchanged after stress (P>0.05 for both), whereas that of EN group significantly increased (from 0.0289+/-0.0070 to 0.0331+/-0. 0084) (P<0.01). Chow group gained body weight (4.9+/-4.3 g). EN+Fiber group lost less body weight (-3.1+/-3.4 g) than EN group (-6.6+/-5.2 g) (P<0.05). The intestinal structure of Chow and EN+Fiber groups was superior to that of EN group. In conclusion, dietary fiber could protect the IBF of 5-Fu stressed rats.

A fusion protein consisting of human calmodulin (CaM) and glutathione S-transferase (GST) was produced by gene fusion. The fusion protein was overexpressed in Escherichia coli as a soluble form and purified with one-step affinity chromatography using glutathione-Sepharose. The protein had the modulating activity of CaM and the binding capability to glutathione of GST. Phosphodiesterase, which is a CaM dependent enzyme, was activated by the fusion protein, with the Ca2+ level equal to the level equivalent to a native CaM. Furthermore, CaM could be immobilized on a solid-phase matrix through the use of GST moiety while its modulating activity was retained. Phosphodiesterase activity was switched on and off by the immobilized CaM with or without Ca2+, and repeated use of CaM was demonstrated.

LMP2 and LMP7, two subunits of the proteasomes encoded in the major histocompatibility complex, are speculated to play a role in the generation of endogenous peptides for presentation by class I molecules to cytotoxic T cells. Their possible role in the pathogenesis of insulin-dependent diabetes mellitus (IDDM) has not been documented. In this study of Caucasian subjects, we have analyzed the polymorphisms of four genes within the HLA class II region (LMP2, LMP7, and HLA-DRB1 and -DQB1) in 198 unrelated IDDM patients and 192 normal controls ascertained from the southeastern United States. A genomic polymorphism of LMP7 was found strongly associated with IDDM, and the Arg/His-60 polymorphism in LMP2 was found associated with IDDM only in subjects containing an HLA DR4-DQB1*0302 haplotype. To determine whether the apparent associations between LMP genes and IDDM resulted from the strong linkage disequilibria observed between LMP and HLA-DR/DQ genes, we compared LMP gene frequencies in extended LMP-HLA haplotypes derived from control and diabetic families. Our results suggest that LMP genes have independent effects on IDDM susceptibility.