Altered DNA-cleavage activity of topoisomerase II from WEHI-3B leukemia cells with specific resistance to ciprofloxacin

In order to investigate the mechanisms of drug resistance arising in tumor cells, we investigated the capacity of fluoroquinolones to inhibit the in vitro growth of WEHI-3B monomyelocytic leukemia cells and then we established a variant of this line (currently maintained in the absence of drug). The line, named WEHI-3B/CPX, expresses a specific resistance to ciprofloxacin (CPX; resistance index=17.3+/-2.2), and does not show cross-resistance with other fluoroquinolones, camptothecin and topoisomerase II inhibitors such as doxorubicin, etoposide and teniposide. Although a little decrease in intracellular accumulation of CPX is observed in WEHI-3B/CPX cells, these cells do not express MDR or LRP markers, and the resistance is not circumvented by verapamil. Purified nuclear extracts from WEHI-3B and WEHI-3B/CPX cells were tested for topoisomerase I catalytic activity and checking in vitro topoisomerase I sensitivity to CPX and camptothecin inhibition, but no difference was observed. As the treatment with CPX showed that the resistant cell line suffers a significantly lower number of breaks in the DNA molecule we also addressed our investigations to the topoisomerase II-dependent DNA cleavage that, in the resistant clone, was found dramatically less susceptible to be enhanced by CPX both in pre-strand and post-strand DNA passage conditions. WEHI-3B/CPX cells do not express any character of multidrug resistance and represent a rare case of specific drug resistance to CPX. The specific resistance to CPX observed in these cells is related to a functional decrease of topoisomerase II cleavage activity. It could be consequent to a decreased binding affinity of CPX for the topoisomerase II--DNA complex or to a decreased affinity or specificity of topoisomerase II for its DNA cleavage sites.     

Gingival recessions caused by Herpes Simplex Virus in a patient with COVID‐19 infection

Herpes Simplex Virus type 1 (HSV‐1) is a very common infection often localized in the mucocutaneous junction of the lip. Rarely, it could be detected also in periodontal tissues, associated with an elevated risk of periodontal disease progression and gingival recessions. Recently, HSV‐1 and numerous co‐infections have been reported in literature associated with the Coronavirus and subsequent COVID‐19 disease. This report illustrates a case of HSV‐1 in a patient with Covid‐19 infection, showing the presence of ulcers and vesicles on the gingival margin of maxillary teeth associated with soreness and pain. The histology highlighted the presence of intraepithelial cell ballooning, confirming the diagnosis of HSV‐1 infection.     

Trends in cervical cancer survival in Europe, 1983-1994: a population-based study

OBJECTIVE: To evaluate trends in survival from cervical cancer in Europe and in European countries participating in the EUROCARE study as a function of age, morphology and stage at diagnosis. METHODS: Relative survival and relative excess risk of death within 5 years of diagnosis, as a function of age, morphology and stage, among 73,022 women aged 15-99 years diagnosed during 1983-1994 and followed up to 1999 in each of 18 European countries participating in the EUROCARE study, using data from 34 population-based cancer registries. RESULTS: Overall five-year relative survival was 62%, rising by 2% during the period 1983-1994. The highest survival occurred in Northern and Western Europe and the lowest in Central Europe. Survival falls with age at diagnosis, but mainly for localised disease. Survival is higher for adenocarcinoma in younger women, but higher for squamous cell carcinoma in older women. The proportions of younger women, localised cancer and adenocarcinoma all increased. The main improvements in survival were for women under 65, and for metastatic disease. CONCLUSIONS: Survival in Europe has improved slowly but steadily, but the trend is not geographically uniform. Central European countries and the UK saw little or no improvement, and survival in those countries remains the lowest among participating countries in Europe. Further reduction of cervical cancer mortality in Europe may be expected from expansion of screening, and improvement in the treatment of older women, and of metastatic disease.     

Age-Related Variations of Muscle Mass,Strength, and Physical Performance in Community-Dwellers: Results From the Milan EXPO Survey

Objectives

Declining muscle mass and function are hallmarks of the aging process. The preservation of muscle trophism may protect against various negative health outcomes. Age- and sex-specific curves of muscle mass, strength, and function, using data from a large sample of community-dwelling people, are necessary.

Budd-Chiari syndrome: spectrum of imaging findings

OBJECTIVE: The objective of our study was to illustrate the imaging findings of Budd-Chiari syndrome, including CT, MRI, sonographic, and angiographic findings. CONCLUSION: The key imaging findings in Budd-Chiari syndrome are occlusion of the hepatic veins, inferior vena cava, or both; caudate lobe enlargement; inhomogeneous liver enhancement; and the presence of intrahepatic collateral vessels and hypervascular nodules. Awareness of these findings is important for early diagnosis and appropriate treatment.