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PURPOSE: Despite its prominent contribution to cancer cure and palliation, around 1% to 5% of cancer patients suffer serious side effects from radiotherapy. A cardinal goal in the fields of radiobiology and oncology is to predict normal tissue radiosensitivity of a cancer patient before radiotherapy. Higher tumor control rates are likely if radiotherapy individualization could be achieved by applying predictive approaches. EXPERIMENTAL DESIGN: Here, we make use of the cytokinesis block micronucleus assay to assess radiosensitivity in cell lines derived from two different cell lineages obtained from clinically radiosensitive patients. We determined the micronucleus frequency after graded doses of ionizing radiation to primary fibroblasts and lymphoblast cell lines derived from 36 highly radiosensitive cancer patients. RESULTS: Many cell lines, following exposure to ionizing radiation, from patients with severe clinical reactions to radiotherapy showed statistically significantly higher frequencies of micronuclei than those from patients who had normal reactions to radiotherapy. One individual revealed significantly higher micronucleus frequencies in both cell lineages. Interestingly, lymphoblast cell lines from one patient showed micronucleus frequencies similar to ataxia telangiectasia mutated-deficient cells. CONCLUSIONS: These results indicate that the micronucleus assay may have use for identifying predisposition to clinical radiosensitivity, at least in a subset of patients as a component of a pretreatment radiosensitivity assay for use in the clinic.  相似文献   
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Purpose

AZD3409 is a novel DPTI that has potent activity against both FTase and GGTase-1. The in vitro inhibition profile of AZD3409 was characterized using three different cell lines: mouse embryogenic fibroblasts, transfected with H-RasV12 (MEF), A549 cells (Ki4B-Ras mutation) and MCF-7 cells (no Ras mutation).

Methods

Both cytotoxicity and levels of inhibition of farnesylation and geranylgeranylation were determined in different assays in relation to the concentration of AZD3409. Results were compared with those obtained with the first-generation FTase inhibitor lonafarnib or the GGTase-1 inhibitor GGTI-2147.

Results

The mean IC50 for cytotoxicity of AZD3409 and lonafarnib was 510 and 15,200?nM in MEF cells, 10,600 and 2,740?nM in A549 cells and 6,170 and 9,490?nM in MCF7 cells, respectively. In these cells, the IC50 for FTase activity of AZD3409 ranged from 3.0 to 14.2?nM and of lonafarnib from 0.26 to 31.3?nM. The inhibiting activity of AZD3409 and lonafarnib on general protein farnesylation was comparable with the specific farnesylation levels of HDJ-2. In vitro geranylgeranylation of Rap1a could be inhibited by GGTI-2147 in all three cell lines, but only in MCF-7 cells by AZD3409. These results are in agreement with the IC50 values for GGTase-1 activity as the lowest IC50 for AZD3409 was found in the MCF-7 cell line.

Conclusions

AZD3409 inhibits farnesylation to a higher extent than geranylgeranylation. Both inhibition of farnesylation and geranylgeranylation could not be correlated to the antiproliferative activity of the drug.  相似文献   
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Crimean-Congo hemorrhagic fever (CCHF) was detected in 2 refugees living in a refugee settlement in Kikuube district, Uganda. Investigations revealed a CCHF IgG seroprevalence of 71.3% (37/52) in goats within the refugee settlement. This finding highlights the need for a multisectoral approach to controlling CCHF in humans and animals in Uganda.  相似文献   
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Burkholderia thailandensis, an opportunistic pathogen found in the environment, is a bacterium closely related to B. pseudomallei, the cause of melioidosis. Human B. thailandensis infections are uncommon. We isolated B. thailandensis from water in Texas and Puerto Rico and soil in Mississippi in the United States, demonstrating a potential public health risk.  相似文献   
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PurposePhysician burnout is reported in more than one out of every 2 practicing clinicians and is just as prevalent in training physicians. Burnout severity is also associated with increasing levels of financial debt. Medical professionals are notable for their high and increasing levels of debt; despite this, financial literacy is poor among physicians, and financial education is largely absent from medical education. Radiation oncologists (ROs) are no different in this regard, with 33% of residents reporting high levels of burnout symptoms, 33% carrying >$200,000 of educational debt, and 75% reporting being unprepared to handle future financial decisions. To fill this gap, we reviewed the basic tenets of personal financial health for the early career RO.Methods and materialsThe core concept of financial independence (FI) is introduced, and we review 4 basic tenets of personal financial health for the young medical professional: debt, behavior, investment, and asset protection strategies.ResultsFI is achieved by saving until the desired quality of life can be maintained, independent of employment income. Debt strategy involves minimizing debt accrual, understanding student loans, and having a debt management plan. Behavioral strategy involves setting financial goals, calculating worth and a savings rate, budgeting, and frugal living. The basics of investing include asset allocation, diversification, rebalancing, and minimizing expenses. Finally, asset protection includes insuring against catastrophic events with disability, life, health, liability, and property insurance.ConclusionsHealthy financial practices can lead to FI and may facilitate professional and personal freedoms with the goal of mitigating burnout-associated stressors. The tenets of strong financial health for ROs in the early stages of their career include sound debt, behavioral, investment, and asset protection strategies. Furthermore, initial and continuing financial education is an overlooked but important curriculum component. ROs with their financial houses in order can devote more resources to learning and practicing good medicine while living healthy, rewarding lives.  相似文献   
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