Validation of 64Cu-ATSM damaging DNA via high-LET Auger electron emission

Radioactive copper (II) (diacetyl-bis N4-methylthiosemicarbazone) (Cu-ATSM) isotopes were originally developed for the imaging of hypoxia in tumors. Because the decay of a ⁶⁴Cu atom is emitting not only positrons but also Auger electrons, this radionuclide has great potential as a theranostic agent. However, the success of ⁶⁴Cu-ATSM internal radiation therapy would depend on the contribution of Auger electrons to tumor cell killing. Therefore, we designed a cell culture system to define the contributions to cell death from Auger electrons to support or refute our hypothesis that the majority of cell death from ⁶⁴Cu-ATSM is a result of high-LET Auger electrons and not positrons or other low-LET radiation. Chinese hamster ovary (CHO) wild type and DNA repair–deficient xrs5 cells were exposed to ⁶⁴Cu-ATSM during hypoxic conditions. Surviving fractions were compared with those surviving gamma-radiation, low-LET hadron radiation, and high-LET heavy ion exposure. The ratio of the D₁₀ values (doses required to achieve 10% cell survival) between CHO wild type and xrs5 cells suggested that ⁶⁴Cu-ATSM toxicity is similar to that of high-LET Carbon ion radiation (70 keV/μm). γH2AX foci assays confirmed DNA double-strand breaks and cluster damage by high-LET Auger electrons from ⁶⁴Cu decay, and complex types of chromosomal aberrations typical of high-LET radiation were observed after ⁶⁴Cu-ATSM exposure. The majority of cell death was caused by high-LET radiation. This work provides strong evidence that ⁶⁴Cu-ATSM damages DNA via high-LET Auger electrons, supporting further study and consideration of ⁶⁴Cu-ATSM as a cancer treatment modality for hypoxic tumors.     

Cognitive Interviews of Vietnamese Americans on Healthy Eating and Physical Activity Health Educational Materials

The purpose of this study was to better understand if a health educational presentation using culturally adapted materials was understandable and culturally appropriate, and that the content was retained, in an older Vietnamese American population. This study used cognitive interviewing. A convenient sampling was used to recruit eight participants by staff of a community-based organization from its client base. This is the first study to document that family eating style poses a challenge for estimating food intake among Vietnamese Americans. Participants who ate in a family eating style were not able to recall or estimate the number of servings of protein and vegetables. Some older Vietnamese Americans used food for healing and self-adjusted portion sizes from dietary recommendations. Cognitive interviewing is a useful method to improve comprehension, retention, and cultural appropriateness of health educational materials. Further nutrition research concerning intake measurement in ethnic groups that practice a family eating style is warranted.     

Bidirectional Relationships Between Weight Change and Sleep Apnea in a Behavioral Weight Loss Intervention

Objective

To examine the bidirectional relationship between weight change and obstructive sleep apnea (OSA) in the context of a behavioral weight loss intervention.

Advanced musculoskeletal physiotherapists in post arthroplasty review clinics: a state wide implementation program evaluation

Objective

To evaluate outcomes following a state-wide implementation of post arthroplasty review (PAR) clinics for patients following total hip and knee arthroplasty, led by advanced musculoskeletal physiotherapists in collaboration with orthopaedic specialists.

Lifestyles and Health-Related Outcomes of U.S. Hospital Nurses: A Systematic Review

Background

Nurses’ modifiable lifestyles have important health-related consequences.