Platelet-rich plasma as treatment for persistent ocular epithelial defects.

Platelet- rich plasma (PRP) exhibits regenerative proprieties in wound healing but the biochemical mechanisms are unclear. In this study, autologous PRP with a mean value of 338 × 10(3) platelets/µL was used to treat corneal lesions of different aetiology, while homologous PRP with 1 × 10(6) platelets/µL was used to treat cornel lesions induced by a graft versus host disease. The impact of platelet count on the levels of PDGF AA and BB, VEGF, and EGF in the two PRPs was evaluated after a cycle of freezing/thawing. Treated corneal lesions healed or improved. The levels of PDGF AA and BB, VEGF, and EGF in the autologous PRP raised from 296 ± 61; 201.8 ± 24; 53 ± 14 and 8.9 ± 2 to 1017 ± 253; 924.7 ± 222; 101 ± 46.5 and 174 ± 15.5 pg/mL, while in the homologous PRP were 3.4, 4.5, 3.2 and 2 folds higher, respectively. High level of platelet counts seems not required to treat corneal lesions.

Detection of oncogenic DNA viruses in colorectal cancer.

BACKGROUND: As a part of our search for oncogenic viruses as potential etiological agents in human malignancies, our studies on human papillomaviruses (HPV) were extended to analysis of the 3 polyomaviruses (SV40, BKV and JCV) in colorectal carcinomas. PATIENTS AND METHODS: Archival tumour samples from 71 patients with colorectal cancer were analyzed for the sequences of SV40, BKV, JCV and HPV using PCR-based techniques. HPV genotypes were determined using sequencing and reverse blot hybridization (InnoLipa). RESULTS: Amplification of BKV and JCV with the primer pair PEP-1 and PEP-2 and subsequent restriction digestion of the amplified products with BamH I disclosed BKV in 6/66 (9%) of the samples, whereas none contained JCV. SV40 was amplified in 10/66 (15.1%) samples and confirmed by sequencing analysis. In pair-wise analysis for co-infections, the samples were significantly different in their BKV-JCV and JCV-SV40 status, in contrast to their BKV-SV40 co-infection status. HPV DNA was detected in 22/66 (33.3%) of the samples analysed with either the MY09/11 or SPF primer mix. Of these 22 HPV infections, 7 were single-type infections and 15 contained multiple HPV types. HPV detection or type distribution showed no relationship to the gender of the patients or histological grade of the tumour. HPV status was not significantly related to detection of BKV, JCV or SV40. Similarly, in pair-wise analysis for co-infections, the samples were significantly different in their status of HPV-BKV (p=0.0006), HPV-JCV (p=0.0001), and HPV-SV40 (p=0.019), implicating that HPV and the 3 polyomaviruses are rarely detected concomitantly in the same samples. CONCLUSION: Taking the known molecular mechanisms of action of these individual viruses, there is a chance that these viruses could alter the mechanisms of cell cycle control and inhibit apoptosis, thus potentially causing chromosomal instability and promoting colorectal oncogenesis.

Detection and expression of human papillomavirus oncogenes in non-small cell lung cancer.

Human papillomavirus (HPV) has been found in lung cancer cases with variable frequency. In the present study, we analysed a series of 38 patients with non-small cell lung cancer (NSCLC) (21 paraffin-embedded archival samples and 17 fresh surgical specimens) for the presence of E6 and E7 oncogenes of HPV16, 18 and 31. Eight of the tumours were positive (21%): six HPV16, one HPV16+18, and one HPV31. The normal tissue surrounding the HPV-positive tumour was negative for the presence of the virus. Sequencing analysis of URR, of HPV16, which was the most frequently found HPV type in our cases, showed an adenosine deletion at nucleotide 7861 (E2-binding site) in four out of six patients. Sequencing of the entire E6 and E7 genes of HPV16 showed a T to G transition at nucleotide position 350 of E6, in all examined cases. This mutation is associated to the European variant of HPV16. Analysis of E6 and E7 transcripts was performed on the six fresh surgical specimens infected by HPV16. Our study showed that all of the tumours investigated, except one, contained E6 and E7 transcripts. Only in one case could we identify an unspliced form of the E6 transcript. Our results strengthen the relationship between HPV and NSCLC and support the hypothesis that HPV infection could play a role in bronchial carcinogenesis.