Effect of a low-frequency magnetic field on systemic arterial pressure in spontaneously hypertensive rats

The effect of low-frequency magnetic field (MF) on systemic blood pressure has been studied in chronic experiments on 21 spontaneously hypertensive rats. The animals' kidney area was exposed to MF (induction value 30T). Direct blood pressure measurements have revealed an antihypertensive effect.     

A possible virus cryptic in carnation

Small isometric virus-like particles were found in low concentration in apparently healthy carnations of the Mediterranean, miniature and Chinese type but not in eleven Sim cultivars tested. Most carnations containing these particles were from Italy but some were from France and the USA. The particles were not transmitted by grafting or by mechanical inoculation but were seed-transmitted to a large proportion of seedlings. Antisera to partially purified particles were obtained. The particles did not react with antisera to twenty-eight isometric plant viruses or virus-like particles but were serologically related to similar particles found in carnations in England, Holland and Israel. When negatively stained, the particles were isometric with a diameter of about 29 nm and a rounded rather than angular profile, but without clear substructure; some particles were penetrated by the stain. The particles remained intact in neutral sodium phosphotungstate. After isopycnic centrifugation in CsCl solution, preparations of particles formed a main band of mean density 1.377 g/ml and other fainter bands that varied in intensity and position in different preparations. In thin sections of carnations, no virus-like particles or cytological abnormalities were observed.     

Differetial sensitivity of spontaneously hypertensive rats to the hypothermic effect of dopaminergic drugs

The dopaminergic agonist apomorphine produces dose-related hypothermia in naive rats as does L-DOPA in carbidopa-pretreated rats. The hypothermic responses to these two dopaminergic drugs were significantly more pronounced and prolonged in the spontaneously hypertensive rat than in normotensive Wistar control rats. The greater sensitivity of the SHR to these drugs was reflected as a leftward shift of the dose-response curves for apomorphine- and L-DOPA-induced hypothermias.     

Ultrasonographic assessment of the endometrium in rhesus monkeys during the normal menstrual cycle

This study was undertaken to determine whether cyclical changes in the endometrium of the rhesus monkey could be observed by using ultrasound. Three indices of endometrial size were examined: the antero-posterior (or ventro-dorsal), longitudinal, and transverse diameters. Changes in the ultrasonic reflectivity of the endometrium were also assessed. We have attempted to correlate these endometrial parameters with the hormonal status of the animal. Ultrasonography was performed for an average of 12 consecutive days during 19 menstrual cycles. All ultrasonic recordings were normalized to the day of the estradiol (E2) peak (Day 0). We found that the reflectivity of the endometrium was dependent on the stage of the cycle: during the follicular phase, the endometrium appeared less echogenic (darker) compared to the myometrium; in the luteal phase, the endometrium was more echogenic (lighter). During the follicular phase (Days -9 to 0), there was a linear increase in the antero-posterior (p less than 0.001), longitudinal (p less than 0.05), and transverse (p less than 0.001) diameters. In the luteal phase (Days 1-15), no significant changes were observed in these diameters. An estimated endometrial volume (EEV) was obtained by the product of the antero-posterior, longitudinal, and transverse diameters. Each animal observed during the follicular phase (n = 14) exhibited a peak in the EEV, which correlated with the day of the E2 peak (p less than 0.01). From this study, we conclude that the sonographic appearance of the endometrium of the rhesus monkey reflects the cyclical changes that occur during the menstrual cycle.(ABSTRACT TRUNCATED AT 250 WORDS)     

A simple method using PCR for direct sequencing of genomic DNA from frozen tumor tissue embedded in optimal cutting temperature compound.

Described here is a three-day protocol that directly yields DNA sequence after isolating and PCR amplifying genomic DNA from a small sample of frozen nasopharyngeal carcinoma tissue embedded in optimal cutting temperature (OCT) compound. The method is consistently successful, reproducible and will facilitate the rapid analysis of DNA sequence from very small samples.