Subacute Exposure to Gaseous Pollutants from Diesel Engine Exhaust Attenuates Capsaicin-Induced Cardio-Pulmonary Reflex Responses Involving Oxidant Stress Mechanisms in Adult Wistar Rats.

Intravenous injection of capsaicin produces vagal-mediated protective cardio-pulmonary (CP) reflexes manifesting as tachypnea, bradycardia, and triphasic blood pressure (BP) response in anesthetized rats. Particulate matter from diesel engine exhaust has been reported to attenuate these reflexes. However, the effects of gaseous constituents of diesel exhaust are not known. Therefore, the present study was designed to investigate the effects of gaseous pollutants in diesel exhaust, on capsaicin-induced CP reflexes in rat model. Adult male rats were randomly assigned to three groups: Non-exposed (NE) group, filtered diesel exhaust-exposed (FDE) group and N-acetyl cysteine (NAC)-treated FDE group. FDE group of rats (n = 6) were exposed to filtered diesel exhaust for 5 h a day for 5 days (D1-D5), and were taken for dissection on day 6 (D6), while NE group of rats (n = 6) remained unexposed. On D6, rats were anesthetized, following which jugular vein was cannulated for injection of chemicals, and femoral artery was cannulated to record the BP. Lead II electrocardiogram and respiratory movements were also recorded. Results show that intravenous injection of capsaicin (0.1 ml; 10 µg/kg) produced immediate tachypneic, hyperventilatory, hypotensive, and bradycardiac responses in both NE and FDE groups of rats. However, these capsaicin-induced CP responses were significantly attenuated in FDE group as compared to the NE group of rats. Further, FDE-induced attenuation of capsaicin-evoked CP responses were diminished in the N-acetyl cysteine-treated FDE rats. These findings demonstrate that oxidant stress mechanisms could possibly be involved in inhibition of CP reflexes by gaseous pollutants in diesel engine exhaust.

Patient-reported cognitive impairments and objective neuropsychological deficits in young sarcoma patients undergoing chemotherapy and its comparison to healthy controls: A tertiary health care study from India.

The study aims to investigate the patient-reported cognitive deficits and objective neuropsychological functions in younger adult (YA) sarcoma patients (16-40 years of age). Ninety patients and 30 age-matched healthy controls from a single tertiary healthcare hospital, were recruited into four groups: Pre-chemotherapy (Pre Cx), During chemotherapy (During Cx), Post-chemotherapy (Post Cx) and Controls. Neurocognitive functions were assessed subjectively using FACT-Cog v3 questionnaire; objectively using ACE-III and neuropsychological tests (NPT). FACT-Cog scores of During Cx (P = .041) and Post Cx (P = .008) groups were significantly lower than Pre Cx group. ACE-III scores of During Cx (P = .048) and Post Cx (P = .043) groups were lower as compared to Pre Cx group. In addition, reaction times and accuracies of the NPT (Flanker's, Sternberg's and Emotional Stroop tests) were worse (P < .05) in During Cx and Post Cx groups as compared to either Pre Cx or control groups. In the Post Cx group, the dose of chemotherapy showed significant negative correlation with the Sternberg reaction time (P = .040) as well as the scores of language (P = .047), and attention (P = .044) domains of ACE-III. Observations demonstrate that cancer/chemotherapy-related neurocognitive deficits fail to improve even after cessation of treatment, and high dosage of chemotherapy used, could be an underlying factor. This emphasizes the need for developing 'model of care' in these patients for monitoring the side effects, and possible titration in the therapeutic regimen for sarcoma in YA.