Deposition of collagen III and alterations in basement membrane integrity as candidate prognostic markers in prostate cancer.

The extracellular matrix surrounding the tumor undergoes changes in its organization during the metastasis process. The present study aims to quantify total collagen, collagen I (Col I) and collagen III (Col III), analyze the alignment of collagen fibers and assess the basement membrane integrity in samples from patients with metastatic and non-metastatic prostate cancer. Tissue samples from 60 patients were classified into groups based on prognostic parameters: better prognosis (n = 20), worse prognosis without metastasis (n = 23) and metastatic (n = 17). Picrosirius red with further analysis under polarizing microscope was used to quantify (with validation using immunohistochemistry) and analyze collagen alignment, and Periodic Acid Schiff staining was used to analyze the basement membrane integrity. The Col I/Col III ratio was found to be higher in the metastatic group than in the groups with better prognosis (p = 0.012) and worse prognosis without metastasis (p = 0.018). Basement membrane integrity constitution in malignant tumor tissue differed from that of adjacent non-tumor tissue (p < 0.001). Moreover, the worsening in the tumor tissue integrity was positively correlated with worse prognostic parameters. All in all, absence of Col III and basement membrane integrity might be indicators of poor prognosis in prostate cancer.

Toxoplasma gondii infection impairs the colonic motility of rats due to loss of myenteric neurons.

BACKGROUND: Toxoplasma gondii infection causes intestinal inflammation and diarrhea indicating possible intestinal motor dysfunction. Anatomical studies have shown alterations in the colonic myenteric plexus, but it is unknown whether this impacts motility and therefore whether motility is a target for treatment. We determined whether colonic coordinated movements are compromised by toxoplasmic infection and how it is associated with anatomical changes. METHODS: Male Wistar rats were evaluated at 6, 12, 24, 48, and 72 hours and 30 days postinfection (dpi) and controls. Infected rats received orally 5 × 103 sporulated oocysts of strain ME-49 (genotype II) of T gondii. The colon was collected for anatomical analysis (including the myenteric plexus immunolabeled with HuC/D, nNOS, and ChAT) and motility analysis in vitro (conventional manometry). Fecal output was measured daily. KEY RESULTS: At 12 hours postinfection, T gondii caused hypertrophy of the muscularis externa layer of the distal colon. There was loss of total, nitrergic, and cholinergic myenteric neurons in the proximal colon at 30 day postinfection (dpi); however, only loss of cholinergic neurons was found in the distal colon. Contractile complexes in the middle and distal colon were longer in duration in infected animals, which was associated with slower migration of the colonic motor complex. However, gastrointestinal transit time and fecal pellet output remained unchanged during the T gondii infection. CONCLUSIONS AND INFERENCES: Toxoplasma gondii caused myenteric neuronal loss in the proximal and distal colon and altered the motility pattern in the middle and distal colon to a more propulsive phenotype.

Infection and tissue repair of experimental cutaneous candidiasis in diabetic mice.

PURPOSE: Diabetic patients seem to be predisposed to cutaneous candidiasis. In this study, we evaluated the interference of diabetic conditions in alloxan-induced diabetic mice in relation to the development of C. albicans infection, density of M1 and M2 macrophages, distribution of collagen type I and III and anti-inflamamatory cytokines involved in tissue repair. METHODOLOGY: The mice were treated with intravenous alloxan, and all animals with blood glucose levels >250 mg dl-1 were inoculate with C. albicans intradermally in the hind paw and were studied for up to 21 days. Control groups without alloxan were used. The fungal burden was evaluated by periodic acid-Schiff (PAS) and by counting the colony forming units. Total population of macrophages were targeted with antibody to F4/80 antigen and M2 macrophages with anti-arginase antibody. Anti-inflammatory cytokines from popliteal lymph nodes were determined by capture ELISA procedures. Picrosirius red staining allowed qunantification of collagen types I and III in the infected skin by using a polarized light microscope.Results/Key findings. Diabetic mice, versus non-diabetic mice, showed a significant lower density of F4/80 and M2 macrophages, higher fungal burden, deficiency in interleukin (IL)-4 production, and delayed IL-13 responses. The later clearance of C. albicans enhanced tissue injury, leading to a decrease in collagen type I. Moreover, collagen type III was increased by interference of IL-13 and transforming growth factor-ß cytokines. CONCLUSION: These findings highlight some important changes in diabetic animal responses to C. albicans infection that may be important to the pathophysiological processes underpinning cutaneous candidiasis in diabetic patients.