Role of infectious agents in the carcinogenesis of brain and head and neck cancers

Bovine papillomaviruses (BPVs) are oncogenic DNA viruses, which mainly induce benign lesions of cutaneous and/or mucosal epithelia in cattle. Thirteen (BPV 1–13) different viral genotypes have been characterized so far. BPVs are usually species-specific but BPV 1/2 may also infect equids as well as buffaloes and bison and cause tumors in these species. BPV-induced benign lesions usually regress, however occasionally they develop into cancer particularly in the presence of environmental carcinogenic co-factors. The major transforming protein of BPV is E5, a very short hydrophobic, transmembrane protein with many oncogenic activities. E5 contributes to cell transformation through the activation of the cellular β receptor for the platelet-derived growth factor (PDGFβ-r), it also decreases cell surface expression of major histocompatibility complex class I (MHCI) causing viral escape from immunosurveillance, and plays a role in the inhibition of the intracellular communication by means of aberrant connexin expression. E7 is considered as a weak transforming gene, it synergies with E5 in cell transformation during cancer development. E7 expression correlates in vivo with the over-expression of β1-integrin, which plays a role in the regulation of keratinocytes proliferation and differentiation. Additionally, E7 is involved in cell-mediated immune responses leading to tumour rejection, in anoikis process by direct binding to p600, and in invasion process by upregulation of Matrix metalloproteinase1 (MMP-1) expression. Studies on the role of BPV E5 and E7 oncoproteins in naturally occurring tumours are of scientific value, as they may shed new light on the biological role of these two oncogenes in cell transformation.     

Hypertension as a manifestation of COVID‐19 pneumonia

Several factors such as hypertension, bile duct disease, and age can affect the duration of COVID, which can lead to long COVID. Any course of coronavirus infection could have a diverse nature of clinical forms and should have a personalized approach.     

Role of viruses in the development of breast cancer

The most common cancer worldwide among women is breast cancer. The initiation, promotion, and progression of this cancer result from both internal and external factors. The International Agency for Research on Cancer stated that 18-20% of cancers are linked to infection, and the list of definite, probable, and possible carcinogenic agents is growing each year. Among them, biological carcinogens play a significant role. In this review, data covering infection-associated breast and lung cancers are discussed and presented as possible involvements as pathogens in cancer. Because carcinogenesis is a multistep process with several contributing factors, we evaluated to what extent infection is significant, and concluded that members of the herpesvirus, polyomavirus, papillomavirus, and retrovirus families definitely associate with breast cancer. Detailed studies of viral mechanisms support this conclusion, but have presented problems with experimental settings. It is apparent that more effort needs to be devoted to assessing the role of these viruses in carcinogenesis, by characterizing additional confounding and synergistic effects of carcinogenic factors. We propose that preventing and treating infections may possibly stop or even eliminate certain types of cancers.     

Central corneal thickness and its associations in a Russian population. The Ural eye and Medical Study

BackgroundTo assess central corneal thickness (CCT) and its associations in a Russian population.MethodsThe population-based Ural Eye and Medical Study included 5899 (80.5%) out of 7328 eligible individuals. As part of an ophthalmological and general examination, CCT was measured by Scheimflug imaging.ResultsThe study included 5792 (98.2%) participants (age:58.8 ± 10.6 years;range: 40–94 years) with available bilateral CCT measurements. Mean CCT was larger in Russians than non-Russians (549.5 ± 32.8 µm versus 539.2 ± 33.9 µm; P < 0.001). In multivariable analysis, thicker CCT was associated (regression coefficient r:0.43) with younger age (standardized regression coefficient beta:−0.09; non-standardized regression coefficient B:−0.29;95% confidence interval (CI):−0.39,−0.20; P < 0.001), male sex (beta:0.05; B:3.10; 95%CI:1.18,5.03; P = 0.002), urban region of habitation (beta:0.10; B:6.83; 95%CI:4.61, 9.05; P < 0.001), Russian ethnicity (beta:0.04; B:3.48; 95%CI:1.04, 5.91; P = 0.005), higher level of education (beta:0.04; B:0.97;95%CI:0.29,1.66; P = 0.006), higher serum bilirubin concentration (beta:0.05;B:0.15; 95%CI:0.07,0.23;P < 0.001), lower corneal refractive power (beta:−0.09;B:11.92; 95%CI:−2.50,−1.35; P < 0.001), smaller anterior chamber angle (beta:−0.07;B:−0.38;95%CI:−0.52,−0.24;P < 0.001), higher IOP readings (beta:0.38; B:3.47; 95%CI:3.21,3.73; P < 0.001), and higher rise in IOP readings by medical mydriasis (beta:0.07; B:0.88;95%CI:0.54,1.22;P < 0.001). In that model, CCT was not associated with body height (P = 0.14), previous cataract surgery (P = 0.10), axial length (P = 0.18) or prevalence of glaucoma (P = 0.11). The mean inter-eye difference in CCT was 8.52 ± 13.9 µm (median:6.0;95CI:8.16,8.88). A higher inter-eye CCT difference was associated with older age (beta:0.08; B:0.11;95%CI:0.07,0.15; P = 0.01), lower level of education (beta:−0.04;B:−0.34; 95%CI:−0.60,−0.08; P < 0.001) and status after cataract surgery (beta:0.04; B:2.92;95%CI:1.02,4.83; P = 0.003).Introduction conclusionsIn this ethnically mixed population from Russia with an age of 40+ years, mean CCT (541.7 ± 33.7 µm) was associated with parameters such as younger age, male sex, Russian ethnicity, and higher educational level. These associations may be taken into account when the dependence of IOP readings on CCT are considered. Glaucoma prevalence was unrelated to CCT.Subject terms: Visual system, Optic nerve diseases