The ultrastructural characteristics of the arcuate nucleus and median eminence in rats have been studied by means of formaldehyde-osmium tetroxide fixation method. The observations showed that there are two kinds of neurons (dark and light) in the arcuate nucleus which might be responsible for producing both dopamine and releasing hormones. The tanycytes of the ependyma of the third cerebral ventricle pass longitudinally through the various zones of the median eminence and reach at pericapillary space of the portal vessels. The neurosecretory substance-containing nerve terminals may travel between ependymal cells and even enter the cavity of the third ventricle or end around the basal membrane of the capillaries of the median eminence. The axo-somatic and axodendritic synapses are formed at the perikaryon and dendrites of neurons in the arcuate nucleus. Both agranular type and granular type of axo-axonic synapses are encountered in the fibrous zone of the median eminence. There are also synaptic connections between the basic processes of tanycytes and the large granular vesicle-containing nerve terminals in the palisade zone of the median eminence. The ultrastructural characteristics mentioned above suggest that (1) the releasing (or inhibiting) hormones of the hypothalamus might be released through two routes: into the portal capillaries from nerve terminals directly or into the cerebrospinal fluid of the third ventricle first and uptaken by tanycytes, then transported to the portal capillaries by the basic processes of tanycyte; (2) each step of synthesis, storage, transport and release of the releasing (or inhibiting) hormones could be regulated by nervous mechanism.
In isolated spontaneously beating atria of rabbits, tetrandrine (Tet) and verapamil (Ver) shifted the concentration-rate curves to isoproterenol (Iso) to the right in a non-parallel manner and depressed their maxima. (±)-propranolol behaved as a competitive β-adrenoceptor antagonist.
The pD’2 values of Tet and Ver were 6.48 ± 0.45 and 4.30 ± 0.18, respectively. Hence the antagonistic effect of Ver was stronger than that of Tet. The pA2 of propranolol = 7.86 ± 0.21.
Tet and Ver antagonized the positive chronotropic responses to Ca++ (3.3 mM) in spontaneously beating rabbit atria.
It is proposed that Tet is a calcium antagonist similar to Ver. Its inhibitory effect on the tachycardia induced by Iso is due to its action in Ca++ which may be an essential modulator of the sequence of events linking β-adrenoceptor activation and heart rate response.
A comparison of the effects of tetrandrine (Tet), verapamil (Ver) and propranolol (Pro) on cAMP level and force of contraction was made on isolated left atrial strips of rabbits.
Pro antagonized the increase of cAMP and force of contraction caused by isoproterenol, but Tet and Ver did not. This indicates that Tet and Ver do not react with β-adrenoceptors.
These results are in consistence with those of our previous experiments on cat papillary muscle and rabbit right atrium and further support that Tet may be a Ca++-antagonist, not a β-receptor blocker.
The ECG and transmembrane action potentials of the ventricular cells of 40 albino rabbits at various heart rates under natural breathing were simultaneously recorded. After statistical analysis of the records of 126 units, quantitative relationships between action potential durations (APDs) and heart rates were found and regression equations were obtained by linear regression. In order to eliminate the effect of heart rates on APDs, the correction formulas on APDs were also worked out. After correction the effect of sinus cycle length (SCL) on APDs could be eliminated.
This study has provided a practical method for the study of the effect of different agents on the APDs of ventricular cells under more natural condition. Though the regression equations and correction formulas can only be applied in rabbits under natural breathing, this method might be adopted to work out the corresponding regression equations and correction formulas for other experimental animals. Therefore it has practical significance in a rather broad field.
Im Januar 1982 wurde am Pferdeberg, 20 Kilometer nordwestlich von der Kreisstadt Jiangling, Provinz Hubei, ein sehr altes Grab, das Mazhuan-Grab Nr.l, freigelegt, das durch archäologische Forschungen als ein über 2300 Jahre altes Grab aus der Chu-Dynastie der Streitenden Reiche (475-221 v. Chr.) ausgewiesen wurde. Im Sarg lag eine weibliche Leiche, deren Skelett gut erhalten war, während die Weichteile bereits verwest und nicht mehr zu sehen waren. Von der Oberfläche der Lendenwirbel und der Beckenknochen wurden 32,4 g verbliebene Substanz der Eingeweide abgekratzt und damit parasitologische Untersuchungen durchgeführt, wobei vieleClonorchis sinensis-Eier und eine kleinere Anzahl vonTrichuris trichiurα- Eiem gefunden wurden. Das ist der bis jetzt älteste parasitologisch dokumentierte Fall von diesen beiden Wurmkrankheiten.
Seit einigen Jahren werden in vielen chinesischen Krankenhäusern Harnsteinleiden mit magnetisiertem Wasser behandelt, da die Erfahrungen sehr gut sind.
Seit 1979 werden in unserer Klinik grundlegende Forschungen durchgeführt. — (1) Wir haben mit mehreren unterschiedlichen Apparatetypen zur Herstellung magnetisierten Wassers vergleichende Untersuchungen zur Wirksamkeit der verschiedenen Apparate angestellt; am besten war ein Apparat aus Shanghai, der JW-1 Apparat mit 1350 Gauss und 12 Windungen. (2) Unsere Forschungsarbeit beinhaltet die experimentelle Auflösung von Oxalatsteinen, Harnsäuresteinen und Phosphorsäuresteinen mit normalem und magnetisiertem Wasser. Aus diesen Untersuchungen hat sich ergeben, daß das magnetisierte Wasser Phosphatsteine gut lösen kann. (3) Wir haben durch Untersuchungen die physikalischen und chemischen Charakteristika des magnetisierten Wassers festgestellt; durch die Untersuchungen wurde bewiesen, daß es Kalzium aus Kristallen lösen kann. (4) Wir haben auch tierexperimentelle Untersuchungen durchgeführt. Das Ergebnis zeigte, da\ in den Nieren von Fischen, die in magnetisiertem Wasser gezüchtet worden waren, die Menge des kristallinischen Kalziums sowie der Kalziumspiegel im Nierengewebe erniedrigt waren.
This paper presents the autoptical findings of 4 cases of leptospiral cerebral arteritis involving predominantly large arteries at the base of the brain, especially the middle and anterior cerebral arteries. The main pathological change of this basal cerebral polyarteritis is a proliferative endarteritis which may be classified into three types: acute, chronic and oblitero-sclerous. Specific serological tests for leptospirosis were positive in two cases and in one of these two patients spirochetes were found while in the other, immuno-fluorescence positive substance was demonstrated in the involved cerebral arteries. These findings, together with the clinico-epidemiological data, strongly suggest that the cerebral arteritis in our cases should be the result from leptospirochetic infection.
The role of histamine in acute hypoxic pulmonary hypertension was studied in dogs, and the correlation between the effect of histamine and the characteristics of hypoxic pulmonary response was examined. Acute hypoxic pulmonary vasoconstrictive response was not blocked by H1-receptor antagonist, but was potentiated by H2-receptor antagonist. Combined H1- and H2-receptor blockade failed to modify the hypoxic pulmonary vasoconstriction. It seems that H1-receptor antagonist could abolish the potentiating effect of H2-receptor antagonist. Exogenous histamine dilated lung vessels when pulmonary vascular tone was increased. This is in contrast to its vasoconstrictive effect when pulmonary vascular tone was normal. The vasodilating effect of histamine was blocked by H2-receptor antagonist. It is deduced that histamine probably plays the role of a modulator in hypoxic pulmonary vascular response. The dominant effect of H2-receptor caused by increasing pulmonary vascular tone might be implicated in the modulating effect. Infusion of histamine not only suppressed the pulmonary response to hypoxia, but also attenuated the progressive increase in pulmonary vascular resistance in repeated hypoxia. The reduction of the modulating effect of histamine probably contributes to the progressive increase in pulmonary vascular response to repeated hypoxia.
Embolism from air retained within the open heart has been recognized as a potential hazard in direct vision intracardiac surgery. To assess whether Mmode echocardiography can accurately detect intracardiac air and serve as a means to remove it, we made experiments on 8 dogs and performed echocardiography on 12 patients undergoing open heart surgery. The standard M-mode echocardiogram was obtained from the experiment on an isolated dog’s heart. Intracardiac air could be recognized by the presence of linear echoes and loss of echo free area. In the experiment with the dogs’ hearts in situ, 392 random observations were made. When l.0 ml of air was injected intracardially, sensitivity and specificity were 93.2% and 95.0% respectively, and decreased to 85.7% and 80.6% when 0.25 ml was injected. The success rate of detecting and removing intracardiac air was 95.7% (110/115). During open heart surgery, the intracardiac air of the left ventricle was detected by echocardiography in all 12 patients before its removal. After evacuation, only 2 patients exhibited some residual intracardiac air which needed to be reevacuated. Clearly, M-mode echocardiography may serve as a sensitive and specific tool for the detection and removal of intracardiac air.
Cytogenetic studies were made in 22 patients with acute myelocytic leukemia (AML) (M2), in 12 of whom the banding analysis was satisfactory. 4 of these 12 cases (33.3%) were proved to have 8;21 translocation, among whom one was an adult and the other 3 children. 2 male patients showed loss of Y chromosome and the karyotype was 45,X,-Y,t(8q−, 2lq+); one female patient showed an additional structural rearrangement and the karyotype was 46,XX, t(8q−,21q+),t(3p−:11p+). Out of the 4 patients with t(8;2l) 2 achieved complete or partial remission after treatment and the remission rate was about 50%. The period of survival in these two patients was also longer. They were still alive 12 months after the establishment of the diagnosis. The other 2 patients lived only 1.5–2 months. The short period of survival was probably due to loss of Y chromosome.