Trait mindfulness and the mental and physical health of caregivers for individuals with cancer.

BACKGROUND: Mindfulness plays a role in moderating the negative mental and physical health outcomes associated with caregiving. The aims of this study were to examine the relationship between trait mindfulness and the (1) psychological functioning, (2) health behaviors, (3) and physical health of caregivers for individuals diagnosed with cancer. METHODS: Caregivers completed a battery of questionnaires and examinations assessing sociodemographic characteristics, trait mindfulness, depression, perceived stress, caregiver stress, sleep, diet, physical activity, tobacco use, alcohol use, blood pressure, and BMI. Demographics and cancer diagnostics were collected for the individuals whom caregivers supported. Linear regression, multivariate analyses, and moderator analyses were performed. RESULTS: Of the 78 caregivers, the mean age was 63.9 (S.D.=13.1); 59% identified as female; 97% identified as White. Regression analyses indicated that caregivers who reported higher levels of trait mindfulness reported significantly less perceived stress (b= -4.38, SE= 0.88, p <.001), lower levels of depression (b= -3.74, SE= 1.10, p = .001), greater caregiver quality of life (b= -9.05, SE=2.12, p < .001), better sleep quality (b= -0.98, SE=0.44, p = 0.03), and lower rates of tobacco use (b= -10.12, SE= 3.43, p =.003). Trait mindfulness was not significantly related to diet, alcohol use, blood pressure, or BMI. CONCLUSIONS: Higher levels of trait mindfulness are associated with positive mental and physical health measure for caregivers. Future research would benefit from further examining mindfulness-based interventions and their impacts in mitigating the negative toll of caregiving in the context of cancer.

Protective role of the L-arginine-nitric oxide synthase pathway on preservation injury after rat liver transplantation.

BACKGROUND: A major problem complicating liver transplantation is the preservation injury that results from cold storage and subsequent ischemia/reperfusion injury after organ revascularization. The L-arginine-nitric oxide (NO) pathway has been recognized to play critical roles during infection, inflammation, organ injury, and transplant rejection. Recent data indicates that NO synthesis has beneficial effects in several models of liver injury. The purpose of this study is to examine the role of the L-arginine-NO pathway on preservation injury in an experimental model of rat liver transplantation. METHODS: Orthotopic liver transplantation was performed in syngeneic (LEW to LEW) rats. Liver preservation injury was determined by measuring serum liver function tests 6 to 48 hours after transplantation. In some experiments, rats received L-arginine supplementation 0 to 24 hours after transplantation. In other experiments, NO synthase inhibitors (L-NAME or L-NIL) were injected at the time of isograft revascularization. RESULTS: L-Arginine supplementation decreased hepatic transaminase levels at all time points examined (6-48 hours). L-Arginine produced a significant improvement in liver preservation injury by 12 hours after reperfusion. The NO synthase inhibitor L-NAME caused a significant increase in liver injury 24 hours after injection. The inducible NO synthase (iNOS)-specific inhibitor L-NIL had no significant effect on liver injury. CONCLUSIONS: The results show that L-arginine supplementation and NO synthesis improve hepatic injury and have a protective role in the transplanted liver graft. The protective effect may be mediated by low-level cNOS-derived NO.

Stable expression of human inducible nitric oxide synthase in V79 Chinese hamster cells.

A recombinant expression vector containing the full-length cDNA for human inducible nitric oxide (NO) synthase was constructed for constitutive expression in V79 Chinese hamster cells. Expression was followed by Western analyses using three different NO synthase antisera. Activity remained stable during 4 months of continued cultivation. Activities were 25 pmol min-1 mg-1 cytosolic protein with L-arginine and 47 pmol min-1 mg-1 cytosolic protein with NG-hydroxy-L-arginine as substrates. Activity was concentration-dependently inhibited by inhibitors such as NG-methyl-L-arginine, NG-nitro-L-arginine, NG-nitro-L-arginine methyl ester, aminoguanidine, and S-methyl-isothiourea. The rank order of inhibitor potencies was different from published results obtained with rodent inducible NOS. Parental V79 cells do not express and cannot be induced for NO synthase activity. Therefore, the genetically engineered V79 cell line is defined for the cDNA-encoded human inducible NO synthase. The new cell line may serve as a useful tool to study human inducible NO synthase.