[Sedative-hypnotic effect of caulis Polygoni multiflori decoction]

The sedative-hypnotic effect of Caulis Polygoni multiflori decoction (CPMD) was studied by the rolling cylinder method in mice and by the somnopolygraphic recording method in rats. The result from the rolling method in mice showed that CPMD (9g/kg) did have synergic action with the subthreshold hypnotic dose of sodium pentobarbital (20mg/kg). The result from the somnopolygraphic recording experiment showed that the immediate hypnotic effect of an effective dose of CPMD (20g/kg) was basically similar to that of diazepam (5mg/kg) used under the same experimental condition, chiefly an increase in the duration of slow wave sleep phase (SWS) and a decrease in the duration of paradoxical sleep phase (PS). By the end of a three-day session in dose of twice a day the hypnotic effect appeared more prominent and the reduction of SWS latency became significant.

Second-harmonic generation using gratings optically written by mode interference in poled optical fibers

Second-order nonlinear susceptibility gratings are induced in optical fibers by mode interference of high-intensity blue light in the presence of an external dc electric poling field. As a result, efficient second-harmonic generation can be obtained for any infrared design wavelength.

Monoclonal antibodies specific for type 3 protein kinase C recognize distinct domains of protein kinase C and inhibit in vitro functional activity

Monoclonal antibodies (mAbs) which distinguish Type 3 protein kinase C (PKC) from Types 1 and 2 have been obtained from mice immunized with purified Type 3 PKC from rabbit brain cytosol. Most of these mAbs (seven out of eight) selectively recognize Type 3 versus Types 1 and 2 PKC in both enzyme-linked immunosorbent and immunoblot assays. Trypsin treatment of Type 3 PKC reduced the immunoreactivity with 82-kDa PKC and generated immunoreactive fragments of 45 and 35 kDa. The mAbs can be divided into two classes based on their ability to recognize the 45-kDa catalytic fragment (5/8) or the 35 kDa regulatory domain fragment (3/8). Each of the mAbs inhibits phosphorylation of histone or lipocortin by PKC, although the extent of the inhibition varied. Only those mAbs that recognize the 35-kDa regulatory domain inhibited phorbol ester binding. The inhibition of both kinase and binding activities by this group of mAbs was sensitive to the concentration of phospholipid used in the assay. This functional inhibition suggests that these mAbs may be useful for defining the phospholipid binding domain(s) of Type 3 PKC. The mAbs recognized 82-kDa PKC in a variety of cell types; the presence of smaller molecular weight fragments was not consistently found. Distinct immunofluorescence staining patterns were observed with mAbs directed toward different epitopes, suggesting that there may be heterogeneity in the subcellular localization of PKC. The type specificity of these mAbs will make them valuable tools for studying activation and regulation of Type 3 PKC in cell culture model systems.

Development of physiological responses to acetylcholine during organ culture of young embryonic chick hearts

Young (3 days-old) embryonic chick hearts (i.e., prior to innervation) have a low sensitivity and transient response to acetylcholine (ACh). In the present experiments, in which the hearts were placed into organ culture for a period of up to 7 days, the sensitivity to ACh was found to increase with time in culture, and the inhibitory action of ACh persisted for a longer time (i.e., desensitization declined). Thus, the ability to ACh to slow spontaneous heart rate and to shorten action potential duration (in the atrium) became greater during the course of organ culture. The effects of ACh on spontaneous heart rate and on action potential duration were blocked by atropine. These results suggest that the physiological responses to muscarinic agonists in young embryonic chick hearts continue to develop in organ culture, and that the increased sensitivity to muscarinic agonists seen in ovo is unlikely to be due to the development of innervation.

The endocrinological profile of normal menstrual cycles in a population of Chinese women

Endocrinological profiles of normal menstrual cycles were studied in 41 Chinese women. Daily serum concentration of luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (PRL), estradiol (E2) and progesterone (P) were determined by RIA. Thirty-four cycles were of normal length (26-35 days) and 6 cycles were prolonged up to 40 days with a follicular phase of 22-26 days. One cycle was anovulatory. Cyclical changes of LH, FSH, E2 and P were typical of ovulatory cycles in other populations as reported in the literature. In the normal cycle group the geometric mean of the LH midcycle peak level was 46 IU/1, the FSH peak was 10 IU/1, the preovulatory estradiol peak was 1229 pmol/1 and the progesterone luteal maximum was 50 nmol/1. The pattern of cyclical changes in the prolonged ovulatory cycles was similar to the normal length cycles, except that there were significantly higher levels of LH in both follicular and luteal phases, lower FSH in luteal phase, and lower progesterone in luteal phase. A majority of cycles had a midcycle elevation of prolactin and mean PRL levels in the late luteal phase were higher than those in the follicular phase.

Clearance of liquid from lungs of newborn rabbits

Apparent inconsistencies in the results of previous studies led us to reexamine the process by which fluid leaves the lungs of newborn rabbits after birth. We measured pulmonary blood volume, extravascular lung water, and the size of perivascular cuffs of fluid in frozen sections of lung obtained from 166 full-term rabbits (31 days gestation) born vaginally or by cesarean section. We killed the rabbits by giving them barbiturate intraperitoneally and immersing them in liquid nitrogen before they breathed or at randomly predetermined intervals from 5 min to 24 h after birth. We found that a) pulmonary blood volume of both groups of rabbits increased soon after birth, b) extravascular lung water per gram of dry lung tissue was greater at birth in rabbits born by cesarean section than in those born vaginally, c) extravascular lung water did not begin to decrease in either group of animals until 30-60 min postnatally, after which it decreased progressively for 24 h, and d) the rate of fluid clearance and pattern of puddling around pulmonary vessels was similar in both groups of rabbits, with maximal perivascular cuffs 30 min after birth, followed by diminution of cuff size as the lungs shed water.

The effect of time of cord clamping and maternal blood pressure on placental transfusion with cesarean section

We measured the residual placental blood volume (RPBV) of 20 infants delivered at term by cesarean section of women not in labor. In all cases, the umbilical cord was clamped within 40 seconds of birth. RPBV decreased significantly with increasing age at cord clamping. In addition, RPBV for infants with cords clamped within 20 seconds of birth correlated inversely with maternal systolic blood pressure (mean RPBV = 54.8 ml. per kilogram at 105 torr and 28.4 ml. per kilogram at 148 torr). However, RPBV did not correlate with maternal blood pressure for the whole group of 20 infants or for those with cords clamped later than 20 seconds after birth. These data indicated that in infants delivered by cesarean section placental transfusion is time related during the first 40 seconds of life and that maternal blood pressure also influences the magnitude of placental transfusion during the first 20 seconds after birth. Analysis of data from this study combined with data from a previous study shows that after 40 seconds the net flow between placenta and infant reverses and that cord clamping delayed beyond this point is accompanied by a rise in RPBV back to the level found when the cord was clamped before 20 seconds.

A volume-displacement plethysmograph to measure limb blood flow in the newborn infant

An instrument is described that measures limb blood flow in newborn infants by venous occlusion plethysmography. The plethysmograph is filled with air and a pneumotachygraph measures the volume displaced during venous occlusion. The response of the system is linear for flows over the range 1 to 100 ml/min and the frequency response to a square wave pressure change is 22 Hz with a 95% response time of 0.5 second. The average flow in the forearm of 10 normal newborn infants was 5.9 ml/min per 100 ml of tissue.

Cesarean section prevents placenta-to-infant transfusion despite delayed cord clamping

We have adapted and calibrated an accurate method for measuring residual placement blood volume (RPBV). We used this method in 33 normal vaginal deliveries and 18 cesarean section deliveries in which the umbilical cord was clamped from 5 to 118 seconds after delivery. Infants born vaginally received 10 to 20 ml. per kilogram of body weight of placental transfusion when umbilical cord was not clamped until 30 seconds or more after delivery. Equivalent delay of umbilical cord clamping in cesarean section infants produced no placental transfusion.

Nonuniform distribution of microspheres in blood flowing through a medium-size artery

Suspensions of rigid microspheres, varying from 7.5 to 80 μ diameter, were injected into the left ventricle or ascending aorta of five anesthetized rabbits. After injection, an exposed branch of the femoral artery was frozen ultrarapidly, then removed; after histologic preparation, serial cross sections were studied microscopically. The radial distribution of the spheres within the vessel lumen was uneven, with a progressively decreasing concentration peripherally. This appeared to be proportional to sphere diameter and extended too far in from the periphery to be explained by entrance effect only. Microspheres of 7.5 to 10 μ diameter had the radial distribution which most closely approached that of erythrocytes in these same arteries.