Hemorheology, melatonin and pinealectomy. What\u27s the relationship? An experimental study.

The circadian rhythm of stroke and myocardial infarction (MI) may be related to the circadian rhythm of melatonin, and erythrocyte deformability may be the key mechanism in this relationship. Therefore, this study has been performed to determine if there is a relationship between the pineal gland and melatonin and red cell deformability. Twenty-eight rats underwent pinealectomy, pinealectomy plus melatonin administration (200 mg/kg), or no treatment (n=7 in each group). Erythrocyte deformability was determined using the filtration technique. The results are reported in mean (+/-SD) seconds: control: 1.45+/-0.44; pinealectomy (A): 1.55+/-0.16; pinealectomy (B): 1.34+/-0.26 and pinealectomy and melatonin: 2.56+/-0.69. Pinealectomy by itself did not cause any statistically significant change in erythrocyte deformability but the addition of melatonin significantly decreased it. These results suggest a relationship between melatonin and erythrocyte deformability. Further investigations may uncover the causes of the circadian rhythm of stroke and MI, which may help improve chronobiological therapies

Using computer based data acquisition and analysis system for nasal potential difference measurement in cystic fibrosis.

Nasal potential difference (PD) measurement has been used as a diagnostic test for cystic fibrosis (CF). It has been shown that large differences in reproducibility of nasal PD measurement can exist between different study sites. These differences reduce the validity of studies. In our study we tried to measure nasal PD values for a group of Turkish CF patients by using a computer based data acquisition system, which could eliminate the bias due to using different voltmeters. The CF group (n=40, mean age 9.3 years) value was -39.21+/-1.74 mV, and the control group (n=36, mean age 17.08 years) value was -18.24+/-1.48 mV (mean+/-SEM). Using the electronic data acquisition and analysis systems gave reliable results with high specificity (92%), sensitivity (79%), positive predictive value (95%) and negative predictive value (72%). Computer based data acquisition and analysis system provides suitable monitoring and continuous recording during measurements and facilitates repeat readings at the same distances along the nasal floor. Using electronic data acquisition may help to minimize the subjectivity in voltmeter measurements and hand analysis