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Despite the increasing interest in polyamide-based composites, few studies on polyamide-based natural fiber composites have been conducted due to their high melting temperatures of polyamide 6 (PA6). In this study, kenaf fiber-reinforced polyamide 6 composites (KF/PA6) were successfully prepared and their properties were investigated. Thermogravimetric analysis demonstrated that the neat PA6 has higher thermal stability with higher melting temperatures of 426°C, respectively, than KF/PA6 composites. The results of the differential scanning calorimeter showed that the glass transition temperature (T g) of KF/PA6 composites was slightly shifted to a higher temperature at 59°C than that of the neat PA6 at 45°C. The thermal and mechanical characteristics using dynamic mechanical analysis results showed that the storage and loss modulus of the neat PA6 were higher than those of KF/PA6 composites. The neat PA6 showed the maximum tensile strength of 48 MPa; however, the maximum tensile modulus was obtained at 10 wt% KF with 2,100 MPa. The flexural strength and modulus of the neat PA6 were 91 and 2,506 MPa, respectively, which were higher than those of KF/PA6 composites. The impact strength also deteriorated with the addition of KF, from 3.72 to 1.91 kJ·m−2. Voids, fiber pulled-out, and agglomeration were observed in scanning electron microscope analysis on the tensile fractured surfaces.

Purpose: A common side effect of chemotherapy treatment is diarrhoea. Unfortunately, the underlying mechanisms of chemotherapy-induced diarrhoea (CD) are poorly understood. We aimed to determine if faecal microbes of CD patients were displaced, if faecal calprotectin increased during CD and if there were alterations in circulating matrix metalloproteinases, nuclear factor kappa B (NF-κB), IL-1β and TNF., Patients and Methods: Twenty-six cancer patients receiving chemotherapy were enrolled and requested to provide stool samples and blood samples at various times during their chemotherapy cycle. Stool samples were analysed using conventional culture techniques and qRT-PCR. ELISA kits determined faecal calprotectin levels, levels of circulating matrix metalloproteinases and circulating NF-κB, IL-1β and TNF., Results: The majority of patients with CD showed decreases in Lactobacillus spp., Bifidobacterium spp., Bacteroides spp. and Enterococcus spp. Increases were observed in Escherichia coli and Staphylococcus spp. Methanogenic archaea were also quantified, with all patients except one showing a decrease. Faecal calprotectin levels were increased in 81.25 % of patients with CD. Circulating MMP-3 and MMP-9 significantly increased following chemotherapy. Circulating levels of NF-κB, IL-1β and TNF were increased following chemotherapy, although this did not reach significance., Conclusions: We demonstrated that CD is associated with marked changes in intestinal microflora, methanogenic archaea, matrix metalloproteinase and serum levels of NF-κB, IL-1β and TNF. These changes may result in diminished bacterial functions within the gut, altering gut function and initiating intestinal damage, resulting in the onset of diarrhoea. More importantly, these changes may provide clinicians with a possible new target for biomarkers of toxicity.