Mechanisms by which extracellular ATP and UTP stimulate the release of prostacyclin from bovine pulmonary artery endothelial cells

Extracellular ATP and UTP caused increases in the concentration of cytoplasmic free calcium ([Ca2+]i) and the intracellular level of inositol 1,4,5-trisphosphate (IP3), a second messenger for calcium mobilization, prior to the release of prostacyclin (PGI2) from cultured bovine pulmonary artery endothelial (BPAE) cells. The agonist specificity and dose-dependence were similar for nucleotide-mediated increases in IP3 levels, [Ca2+]i and PGI2 release. An increase in [Ca2+]; and PGI2 release was observed after addition of ionomycin, a calcium ionophore, to BPAE cells incubated in a calcium-free medium. The addition of ATP to the ionomycin-treated cells caused no further increase in [Ca2+]i or PGI2 release. The inability of ATP to cause an increase in [Ca2+]i or PGI2 release in ionomycin-treated cells was apparently due to the ionomycin-dependent depletion of intracellular calcium stores since the subsequent addition of extracellular calcium caused a significant increase in both [Ca2+]i and PGI2 release. Introduction of BAPTA, a calcium buffer, into BPAE cells inhibited ATP-mediated increases in [Ca2+]i and PGI2 release, further evidence that PGI2 release is dependent upon an increase in [Ca2+]i. The increase in [Ca2+]i elicited by ATP apparently caused the activation of a calmodulin-dependent phospholipase A2 since trifluoperazine, an inhibitor of calmodulin, and quinacrine, an inhibitor of phospholipase A2, prevented the stimulation of PGI2 release by ATP. Furthermore, ATP caused the specific hydrolysis of [14C]arachidonyl-labeled phosphatidylcholine and the generation of free arachidonic acid, the rate-limiting substrate for PGI2 synthesis, prior to the release of PGI2 from BPAE cells. These findings suggest that the increase in PGI2 release elicited by ATP and UTP is at least partially dependent upon a phospholipase C-mediated increase in [Ca2+]i and the subsequent activation of a phosphatidylcholine-specific phospholipase A2. ATP analogs modified in the adenine base or phosphate moiety caused PGI2 release with a rank order of agonist potency of adenosine 5'-O-(2-thiodiphosphate) (ADP beta S) greater than 2-methylthioATP (2-MeSATP) greater than ATP, whereas alpha, beta methyleneATP and beta, gamma methyleneATP had no effect on PGI2 release.

Heterogeneity of ventricular remodeling after acute myocardial infarction in rats

To determine the effects of acute myocardial infarction on the extent and distribution of systolic and diastolic wall stress on the surviving myocardium, coronary artery occlusion was produced in rats, and the animals were killed 1 wk later. After hemodynamic measurements in vivo, the characteristics of cardiac anatomy at end diastole and peak systole were mimicked in vitro by fixing hearts under diastolic conditions or barium-induced contracture. In the presence of infarcts inducing a 48% loss of myocytes, left ventricular failure was documented by increases in left ventricular minimal and end-diastolic pressures and decreases in peak systolic pressure and positive and negative rates of pressure change with time. End-diastolic and end-systolic volumes increased, whereas stroke volume and cardiac output diminished. Ventricular remodeling in diastole consisted of an increase in the longitudinal axis while both longitudinal and transverse mid-chamber diameters were augmented after systolic contraction. Left ventricular chamber volume enlarged by 44% through a 20% augmentation in the longitudinal diameter and increases in the transverse luminal diameter of 13, 21, 32, and 37% in four consecutive sites from the equatorial region to the apex. As a consequence of infarction, systolic thickening of the spared myocardium of the free wall was reduced progressively from the base to the apex. In the interventricular septum of the infarcted heart, systole thickening occurred mostly in the equatorial region and was reduced at the basal and apical portions. The interaction of hemodynamic impairment with the architectural rearrangements of the wall and chamber provoked a 1.9-fold increase in overall stress on the spared myocardium. However, diastolic stress was augmented by 6.8-fold, markedly exceeding the 1.1-fold increase in systolic stress. Thus large infarcts of the rat left ventricle due to left main coronary occlusion lead to a change in shape of the heart from ellipsoidal to cylindrical. The elevation in overall stress may condition the unfavorable long-term outcome of the infarcted heart.

[Analysis of 20 cases of amitriptyline poisoning]

20 cases of amitriptyline poisoning have been reported. The main symptoms were come in different degrees, pupil dilatation, tachycardia, retention of urine. Raising of blood pressure and subnormality of body temperature appeared in part of patients. There were convulsive attacks in some severe patients. EKG were abnormal in half of patients. Besides gastric lavage and acceleration of excretion, using of physostigmine was one of the important reused steps, it often was the determinate factor to get success. Convulsive attack was the main dangerous to death. Some discussions have been made about relative problems.

Efficient production of single-stranded DNA as long as 2 kb for sequencing of PCR-amplified DNA

A modification of the asymmetric PCR method is described, which reliably facilitates sequencing of PCR-amplified DNA. This procedure produces single-stranded DNA fragments as long as two kilobases that are suitable for dideoxy DNA sequencing. First, a PCR for double-stranded DNA is preformed under optimal conditions (double-stranded PCR). Then, a 5-10-microliters fraction of the double-stranded PCR and a single primer are used to generate single-stranded DNA in a separate PCR (single-stranded PCR). The concentration of the single primer are used to generate single-stranded DNA in a separate PCR (single-stranded PCR). The concentration of the single primer is approximately 0.4 microM. Usually 15 to 25 cycles of single-stranded PCR are optimal to produce single-stranded DNA for four to eight sequencing reactions. The single-stranded DNA is purified by centrifugal ultrafiltration and used directly in dideoxy sequencing. This method was employed to produce high-quality single-stranded DNA templates from a variety of organisms for efficient DNA sequencing of PCR-amplified DNA.

Chronic coronary artery constriction leads to moderate myocyte loss and left ventricular dysfunction and failure in rats

Coronary artery narrowing, ranging from 19% to 61%, was induced in rats and ventricular performance, myocardial damage, and myocyte hypertrophy were examined 1 mo later. Animals were separated into two groups, exhibiting ventricular dysfunction and failure, respectively. Dysfunction consisted of a 2.4-fold increase in left ventricular end diastolic pressure (LVEDP), 15% decrease in left ventricular peak systolic pressure (LVPSP), 24% reduction in developed pressure (DP), and a 16% depression in-dP/dt. Failure was defined on the basis of a 4.7-fold elevation in LVEDP, and a 26%, 47%, 45%, and 41% decrease in LVPSP, DP, +dP/dt, and -dP/dt. Moreover, in this group, right ventricular end diastolic and systolic pressures increased 5.5- and 1.2-fold. Left and right ventricular weights expanded 23% and 51% with dysfunction and 30% and 56% with failure. Left ventricular hypertrophy was characterized by ventricular dilation and wall thinning which were more severe in the failing animals. Foci of damage were found in both groups but tissue injury was more prominent in the endomyocardium and in failing rats. Finally, myocyte loss in the ventricle was 10% and 20% with dysfunction and failure whereas the corresponding enlargements of the unaffected myocytes were 34% and 53%. Thus, coronary narrowing led to abnormalities in cardiac dynamics with an increase in diastolic wall stress and extensive ventricular remodeling in spite of a moderate loss of myocytes and compensatory reactive hypertrophy of the viable cells.

Down-regulation of E1a expression by E3 gene products in group C adenoviruses

Mutant group C adenoviruses defective in expression of the E3 transcription unit were found to overexpress E1a proteins relative to wild-type adenoviruses. This result suggests that one or more proteins encoded in the E3 region (present in wild-type viruses) down-regulate E1a expression. This interpretation was confirmed by transfection experiments in which a plasmid expressing the E3 region reduced expression of E1a in 293 cells. Experiments to examine the molecular basis of this down-regulation of E1a suggest that E3 protein products interfere with the translation of viral mRNA molecules.

Granulocyte sequestration and early failure in the autoperfused heart-lung preparation

We investigated the role of pulmonary granulocyte sequestration in the development of early failure of the autoperfused working heart-lung preparation. A significant decline in the total circulating leukocyte count in 21 preparations at 60 minutes of perfusion (5.0 to 1.4 x 10(3)/microL; 28% of baseline; p less than 0.001) was observed. Differential cell counts in 14 of these preparations revealed a predominant decrease in granulocyte count (8.7% of baseline) and a moderate decline in lymphocyte count (46% of baseline). In study I, indium 111-labeled autologous granulocytes were injected intravenously into 10 adult New Zealand White rabbits. In group I (n = 5), an autoperfused working heart-lung preparation was harvested and perfused for 60 minutes. In group II (controls, n = 5), the heart-lung block was harvested following 60 minutes of in situ perfusion. Organ blocks were imaged before and after saline flush. There was a significant decline in granulocyte counts at 60 minutes of perfusion in group I versus no change in group II (I, 2.3 +/- 0.4 to 0.3 +/- 0.1; p less than 0.01; II, 1.7 +/- 0.2 to 2.3 +/- 0.5; not significant; x 10(3)/microL +/- standard error of the mean). Postflush lung activity was significantly increased in group I versus group II (I, 3,751 +/- 566; II, 1,867 +/- 532; p less than 0.05; counts +/- standard error of the mean). In study II, 15 autoperfused preparations were divided into two groups. Group I (n = 10) preparations were controls. Group II (n = 5) animals were depleted of leukocytes by pretreating with nitrogen mustard. Group I (controls) produced a bimodal survival distribution (Ia, 8.2 +/- 1.0; Ib, 26.4 +/- 2.0; hours +/- standard error of the mean). Group II survival was significantly longer than that of group Ia and similar to that of group Ib (II, 25.3 +/- 2.2; p less than 0.01 versus group Ia, not significant versus group Ib; hours +/- standard error of the mean). Hemodynamic profiles for group II closely paralleled those of group Ib. In conclusion, pulmonary sequestration of granulocytes occurs early in the autoperfused working heart-lung preparation (within 60 minutes of autoperfusion), and preoperative leukocyte depletion prolongs survival of the autoperfused working heart-lung preparation by eliminating the subset group Ia (short survivors) seen in untreated preparations.

Chronic nonocclusive coronary artery constriction impairs ventricular function, myocardial structure, and cardiac contractile protein enzyme activity in rats

To determine the effects of chronic nonocclusive coronary constriction on cardiac hemodynamics, structural integrity, and contractile protein enzyme activity, the left coronary artery was narrowed in rats, and measurements of ventricular performance, magnitude, and distribution of tissue damage and myofibrillar Mg2+ and Ca2+ myosin ATPase activities were evaluated 1 month later. In the presence of coronary artery stenosis averaging 58%, three levels of involvement of global cardiac performance were identified, and the rats were divided accordingly. In the first group, only left ventricular end-diastolic pressure (LVEDP) was increased; in the second group, LVEDP and left ventricular +dP/dt and/or -dP/dt were affected; and in the third group, LVEDP, left ventricular +dP/dt and -dP/dt, and right ventricular end-diastolic pressure were impaired. Thus, left ventricular moderate dysfunction, severe dysfunction, and failure occurred with coronary narrowing. On a structural basis, coronary constriction resulted in an ongoing process characterized by acute myocytolytic necrosis and foci of replacement fibrosis in different stages of healing. The number of these lesion profiles in the left ventricular myocardium increased 4.7-, 4.4-, and 8.3-fold in rats with moderate dysfunction, severe dysfunction, and failure, respectively. Biochemically, Mg(2+)-ATPase activity of myofibrils increased biventricularly when moderate dysfunction was present. However, this parameter decreased with the appearance of severe dysfunction, reaching control values in ventricular failure. Ca2+ myosin ATPase activity was reduced in the left ventricle of rats with severe dysfunction and failure, whereas it was elevated in the right ventricle of rats with severe dysfunction. In conclusion, a fixed lesion of the left main coronary artery with a modest reduction in vessel luminal diameter generates a conditioned state of the heart characterized by a continuous loss of myocytes and replacement scarring, which, in combination with alterations in contractile protein enzyme activity, may be responsible for a number of abnormalities in cardiac dynamics ranging from moderate dysfunction to pump failure.

Effects of lorazepam tolerance and withdrawal on GABAA receptor operated chloride channels in mice selected for differences in ethanol withdrawal severity

Withdrawal seizure prone (WSP) and withdrawal seizure resistant (WSR) mice were treated with 5 mg/kg lorazepam for 7 days via implanted osmotic mini pumps. Following chronic drug treatment, brains were assayed for GABA-mediated chloride flux (GABA-Cl-). Under control (drug naive) conditions, brain membranes prepared from WSP and WSR lines did not differ in flunitrazepam or ethanol stimulation of GABA-mediated 36Cl- uptake, but the WSP lines were more sensitive to inhibition of 36Cl- flux by the inverse agonist, FG-7142. Membranes from lorazepam tolerant WSP and WSR mice were resistant to flunitrazepam- and ethanol-stimulation of GABA-Cl-. Withdrawal from chronic treatment, by an acute injection with the benzodiazepine antagonist RO15-1788, returned flunitrazepam stimulation of GABA-Cl- to near control levels in WSR membranes but not in WSP membranes and restored ethanol modulation of the channel to control levels in both lines. Inhibition of chloride flux by the benzodiazepine partial inverse agonist, FG-7142 was greater in membranes from WSP mice compared with WSR mice. Tolerance to lorazepam increased sensitivity of the WSR membranes to FG-7142 without altering the response in the WSP line. Again, withdrawal restored the Cl- flux response to FG-7142 back to near control levels. Lorazepam tolerance lowered [3H]-flunitrazepam binding affinity slightly only in the WSR strain with no change in binding number. Withdrawal from chronic lorazepam treatment produced no significant change in binding affinity or number. The initial genotypic differences in benzodiazepine inverse agonist sensitivity, may be related to the selection for withdrawal seizure severity. Chronic administration of lorazepam reduces the coupling between the benzodiazepine agonist site and the chloride channel and concomitantly increases coupling between the channel and the inverse agonist site, while withdrawal resets the receptor coupling back to control response levels. However, for the WSP line, this drug environment dependent shift in channel coupling bias appears to be deficient compared with the WSR line.

Differential radioprotection of cultured human diploid fibroblasts and fibrosarcoma cells by WR1065

The present studies were performed to determine whether WR1065, the dephosphorylated, free-thiol active metabolite of WR2721, could provide differential radioprotection of normal and tumor cell lines in vitro and secondly to investigate potential mechanisms for the selective nature of the radioprotection at the cellular and molecular level. When 4 mM WR1065 was administered 30 min prior to and during irradiation, a protection factor of 1.9 was obtained in clonogenic assays performed with normal human diploid fibroblasts (AG1522) while no protection of fibrosarcoma cells (HT1080) was observed. Some radioprotection of fibrosarcoma cells was observed with higher drug concentrations (10-40 mM), but the increase in survival was considerably less than the plateau level reached with the diploid fibroblasts (3-fold vs 24-fold at 6 Gy). The observation of such a selective effect in vitro with WR1065 indicates that differences in tissue-specific variables such as blood flow, pH, pO2, and drug dephosphorylation cannot solely account for the selective nature of the radioprotection afforded by WR2721 in vivo. Incubation of nucleoids with increasing concentrations of the DNA intercalating dye propidium iodide was used to titrate the ability of DNA to undergo supercoiling changes. The relaxation and rewinding of supercoiled DNA loops in isolated nucleoids serves as an indicator of both the presence of DNA damage and inherent differences in DNA loop characteristics. Fibrosarcoma cells had a much larger propidium iodide-relaxable DNA loop size than fibroblasts. The rewinding phase of the DNA supercoiling response is impaired by the presence of radiation-induced DNA strand breaks. Four mM WR1065 resulted in a significant reduction in the amount of rewinding inhibition observed after a dose of 10 Gy in diploid fibroblasts (protection factor = 1.43) but did not alter the response of irradiated fibrosarcoma cells. These results, indicating that WR1065 had a preferential radioprotective effect in vitro on both survival and the manifestation of DNA damage at the nucleoid level, are consistent with the hypothesis that cell type differences in chromatin organization and DNA-drug associations could play a role in the selective radioprotection.

[A comparative study of 6 kinds of nourishing glue]

The experimental results have shown that all six kinds of glue have a common protein zone, but only the pipefish glue has a band on the negative electrode side. They are all rich in amino acids. Oxhide glue has the highest content of amino acids, total Ajiao has the highest content of essential amino acids, but Ajiao and pipefish glues do not have cystine. Pharmacological study has shown that deerhorn glue, turtle shell glue and oxhide glue can enrich blood; the number of white blood cells can be elevated by tortoise plastron glue and pipefish glue; deerhorn glue possesses an anti-fatigue effect; deerhorn glue and pipefish glue help to increase the weight of thymus in mice when the solution of glue (10%) is administered into the stomach at a dose of 0.5/mouse per day for 11 days.

Frequencies of HIV-reactive B cells in seropositive and seronegative individuals

Peripheral blood mononuclear cells (PBMC) from HIV-infected seropositive (HIV+) but not from normal, seronegative (HIV-) individuals are known to produce anti-HIV antibodies in vitro, in the absence or presence of pokeweed mitogen (PWM). Previous studies showed that up to 20-40% of spontaneously immunoglobulin-secreting B cells from HIV+ individuals are HIV-specific. To analyse the frequency of anti-HIV B cells among 'total' peripheral blood B cells in the present study, we used a limiting dilution assay in which EL-4 thymoma cells induce clones of immunoglobulin-secreting cells in activated as well as resting B cells. Anti-HIV B cells were detected not only in 11/12 HIV+ individuals (with frequencies from 1/910 to 1/21,500 B cells cultured; one negative test was from a person undergoing seroconversion), but also in 4/9 HIV- normal blood donors (1/16,200 to 1/49,000 B cells cultured) and in 3/6 newborns from HIV- mothers (1/11,800 to 1/26,600 B cells cultured). The mean frequency was nine times higher in the HIV+ individuals than in the normal donors. As in previous studies, only the cells from HIV+ individuals generated anti-HIV antibodies in PBMC bulk cultures with or without PWM. The relative proportion of specific anti-HIV antibody/total immunoglobulin in PBMC bulk cultures was 800 times higher by the mean than in EL-4 B cell cultures from HIV+ individuals (whereby the total immunoglobulin secretion for equal numbers of B cells cultured was 500 times lower for PBMC). These different results obtained with different assays suggest that in seropositives most anti-HIV B cells belong to an activated B compartment which is quite small, even in a disease with B cell hyperactivity. Therefore, the specific B cells are strongly diluted among the EL-4 cell-responsive, total B cells. On the other hand, the EL-4 assay can detect HIV-reactive B cells in the B cell repertoire of normal, non-infected individuals.

[Hypocrellin A induced photodamage to the fluidity of human erythrocyte membranes and membranes of some phospholipid liposomes]

In this paper, the photodamage of Hypocrellin A to the fluidity of human erythrocyte membranes and some kinds of membranes of phospholipid liposomes was investigated by measuring the changes in fluorescence polarization of the membranes. The results showed that the photosensitization effect of HA caused the decrease of membrane fluidity of the phospholipid (DPPC, DPPC/DPPE, phospholipid of erythrocyte membranes) liposomes. The DPPC and DPPC/DPPE liposomes were more sensitive to the damage than the phospholipid liposomes of erythrocyte membranes. To human erythrocyte membranes, the photodamage effect of HA caused its fluidity first increased and then, with the increment of illumination time, decreased. To spectrin-depleted and trypsin-treated erythrocyte membranes, this kind of change in fluidity was inhibited. All of the results indicated that phospholipids and proteins play different roles in the photodamage of HA to the fluidity of membranes. Membrane proteins, especially spectrin, were the key factor involved in the changes of the fluidity.

Incidence survey of aplastic anemia in China

A nationwide cooperative incidence survey of aplastic anemia (AA) was carried out from 1986 to 1988. The cooperative survey network covered 44 investigating areas, involving 21 provinces, municipalities and autonomous regions. More than 52 million person-years were supervised and 387 new cases identified. The annual incidence rate was 0.74/10(5) and the 95% confidence interval of the population rate ranged from 0.67/10(5) to 0.82/10(5). The incidence rate of AA in coal mines was higher than that in other areas. The incidence rate of chronic aplastic anemia (CAA) was 0.60/10(5) and that of acute aplastic anemia (AAA) was 0.14/10(5). There were incidence peaks of CAA at older ages; at age 50-59 in females, but after 60 in males. The incidence rate of CAA in males decreased obviously at age 40-49 and that in females rose clearly at age 10-19, while the incidence rate of CAA in males was generally higher than that in females.

Inhibition of HIV replication by baicalin and S. baicalensis extracts in H9 cell culture

Crude extracts of Scutellia baicalensis and a particular low molecular weight substance known as Baicalin were shown to inhibit HIV antigen expression in H9 cell culture, with 50% inhibitory doses of 0.6 microgram/ml and 3.3 micrograms/ml, respectively. They also inhibited P24 antigen production in H9 cells, with IC50's of 1.94 and 4.74 micrograms/ml, respectively. Cytoxicity was tested in H9 and HUT78 cells: Both exhibited relatively low levels of cytoxicity. These results indicated that S. baicalensis and Baicalin strongly inhibit HIV replication in cell culture.

Identification of negative-strand complements to cytochrome oxidase subunit III RNA in Trypanosoma brucei

A substantial amount of cytochrome oxidase subunit III (COIII) mRNA continues to be synthesized de novo in Trypanosoma brucei in the presence of actinomycin D, presumably by a DNA-independent transcription process. We describe the identification of negative-strand COIII RNA molecules, characterization of their termini, and the detection of RNA-dependent RNA polymerase activity. Three lines of evidence for the existence of negative-strand COIII RNA are presented: (i) hybridization with oligonucleotide probes with the same polarity as mRNA after preliminary enrichment for putative negative-strand RNA by affinity purification; (ii) cloning and sequencing of negative-strand complements for the unedited, edited, and partially edited COIII RNA; and (iii) exact correspondence of the terminal sequences of the putative negative-strand RNA molecules to the ends of COIII RNA. The presence of negative-strand complements of COIII RNA is consistent with the notion that a significant amount of mRNA in T. brucei is synthesized by an RNA-dependent RNA polymerase with negative-strand RNA as an intermediate template.

Coronary artery narrowing in rats: mechanical alterations of left and right myocardium

To determine the effects of chronic coronary artery narrowing on myocardial contractile performance, nonocclusive constriction of the left coronary artery near its origin was surgically induced in rats and global cardiac hemodynamics, left and right myocardial mechanics, and the magnitude and distribution of tissue damage and interstitial fibrosis in the left ventricular wall were analyzed 1 mo later. Reductions in coronary artery luminal diameter of 55% resulted in left ventricular failure as characterized by decreases in systemic arterial pressures, systolic ventricular pressure, rise and decay in first derivative of left ventricular pressure (+/- dP/dt), and an increase in left ventricular end-diastolic pressure. Right side dysfunction was also present as documented by an elevation in right ventricular end-diastolic pressure and a reduction in -dP/dt. In vitro measurements of papillary muscle mechanics revealed a biventricular reduction in isometric developed tension and peak rates of tension rise and decay. Moreover, the kinetic parameters of isometric contraction duration, time to peak tension and time to one-half relaxation, were significantly shorter in left muscles from coronary artery-narrowed animals. Isotonically, peak muscle shortening was reduced in the left muscle, whereas time to peak shortening was prolonged in the right myocardium. In addition, the velocities of muscle shortening and relengthening were decreased in both ventricles. Foci of replacement fibrosis and diffuse interstitial fibrosis were found in the epimyocardium, midmyocardium, and endomyocardium, demonstrating that a significant amount of myocyte loss occurred throughout the left ventricular wall.(ABSTRACT TRUNCATED AT 250 WORDS)

Activation of corticotropin-releasing factor-containing neurons in the paraventricular nucleus of the hypothalamus by interleukin-1 in the rat

Interleukin-1 (IL-1) alpha was injected into the lateral ventricle of the rat. An antiserum against Fos oncoprotein was used to detect the activated neurons immunohistochemically. A large number of neurons in the parvocellular paraventricular nucleus of the hypothalamus, in an area corresponding to the location of the corticotropin-releasing factor (CRF)-containing neurons, were strongly Fos-like immunoreactive (LI). Double immunostaining for Fos and CRF revealed that many of the Fos-LI cells were CRF-LI. Furthermore, the CRF-like immunoreactivity was greatly enhanced in the rats injected with IL-1 alpha, indicating an increase in CRF synthesis.

A comparative study of the treatment of unilateral fractured and dislocated mandibular condyles in the rabbit

This study evaluated the results of three methods of managing simulated unilateral dislocated fractured mandibular condyles in the rabbit. The first method consisted of surgical reduction of the fractured condyle to its anatomic position and its subsequent fixation with a titanium plate. The second method differed from the first by completely detaching the condyle, then replacing it as free graft. The third method left the fractured condyle in its dislocated position outside the glenoid fossa. Eighteen rabbits were used, 6 animals for each method. Half the animals in each group were killed at 4 weeks, the other half at 14 weeks postoperatively. Clinical, morphologic, functional, radiologic, and histologic examinations were conducted on all animals. The results indicated that open reduction with internal fixation with no disruption of the blood supply to the condyle provided the most favorable results. While closed reduction without internal fixation gave good functional results, definite reduction in ramus height on the operated site was observed in this group of animals. Animals that had open reduction and internal fixation using the condyle as a free graft did not do as well as the other two groups. Despite good mouth opening and occlusion, more animals showed facial asymmetry and it was more severe. None of the condyles were lost as result of necrosis, but healing took longer when compared with the other group of animals.

Analysis of proteins and lipopolysaccharides from Chinese isolates of Coxiella burnetii with monoclonal antibodies

Four Coxiella burnetii isolates in China and two reference strains were compared by SDS-PAGE and immunoblotting. The SDS-PAGE profiles of whole cells and LPS of Chinese isolates Qiyi, Xinqiao, and YS-8 were found closely related to Henzerling strain, and different from the Grita strain. In immunoblot assay of LPS and proteinase K-digested whole rickettsiae minor differences were seen in polysaccharide structure among the Chinese isolates by phase I monoclonal antibody. The present results suggest that the strains reported here may be divided into three groups according to the polysaccharide structure: Xinqiao and Henzerling strains (1), YS-8 and Grita (2), and Qiyi (3).

Ultrastructural characteristics of substance P-immunoreactive terminals in marginal division of rat striatum

In our previous work using immunocytochemical method combined with tract tracing techniques a new subdivision was described in the striatum of the rat. This "marginal division" is more densely filled with substance P, enkephalin and dynorphin B terminals than the rest of the striatum. In the present study, the synaptic organization of the substance P immunoreactive (SPIR) terminals in the marginal division of the rat striatum was studied using electron microscopy and immunocytochemistry for substance P (SP). Four major types of SPIR synapses were identified in the marginal division: axodendritic, axospinous, axo-axonal, and compound synapses. Axodendritic and axospinous synapses, in which the postsynaptic targets were small or large dendrites or spines, were the most common. A few axo-axonic synapses were observed as were several subtypes of compound synapses with more than two synaptic components. SPIR axon terminals formed the presynaptic components of all these synaptic types, but in one case an unlabeled bouton was observed making a synaptic connection onto a SPIR dendrite. Both symmetric and asymmetric SPIR synapses were observed in the marginal division. The vesicles in the SPIR presynaptic boutons were mostly pleomorphic although a few of them were round. The existence of asymmetric synapses, round synaptic vesicles and small postsynaptic dendrites distinguishes the ultrastructure of the marginal division from that of the other parts of the striatum. The complex characteristics of the synaptic organization in the marginal division implies that the SPIR terminals in the marginal division originate from a different source than those in the rest of the striatum. The complexity of the synaptic organization further suggests that the function of the marginal division is different from that of the rest of the striatum.

Fos expression in GHB-induced generalized absence epilepsy in the thalamus of the rat

Using the model of gamma-hydroxybutyrate (GHB)-induced generalized absence epilepsy, the present work investigated the distribution of fos oncoprotein expression in the rat thalamus with fos antibody immunohistochemistry. Thirty minutes after absence-like seizures, some fos-immunoreactive cell nuclei were found in bilateral thalamic paraventricular nuclei (PV). After a further 30 min, a massive bilateral induction of fos was observed in the lateral habenular nucleus (LHb), the PV, the rhomboid thalamic nucleus, and the intralaminar nuclei of the thalamus. These results suggest that the LHb and the midline and intralaminar thalamic nuclei may very likely be involved in the pathophysiology of absence seizures.

Hormonal actions during oocyte maturation influence fertilization and early embryonic development

On the basis of evidence just reviewed, the hormonal requirements during IVM of mammalian oocytes for fertilization and developmental competence may be summarized as follows: 1. Nuclear maturation occurs "spontaneously," without follicular factors or hormones, in all mammalian species. 2. Cumulus cells are necessary during nuclear maturation in culture for fertilization and developmental competence. Their effect is enhanced by the addition of serum or follicular fluid to the maturation medium. 3. FSH retards nuclear maturation, perhaps thereby enhancing subsequent developmental competence by allowing more time for cytoplasmic maturation to occur before fertilization. The effects of FSH are mediated, in part, by soluble factors from cumulus or granulosa cells. 4. FSH in vivo before culture or added in vitro to IVM culture media enhances fertilization and stimulates steroidogenesis (progesterone and estradiol) in cumulus cells. Blockade of steroidogenesis prevents the enhancing effect of FSH on fertilization. Progesterone can substitute for FSH in enhancing fertilization of rat oocytes. 5. Other hormones enhance beneficial effects of FSH, with some apparent species differences: a. Rat: Progesterone may mediate the FSH effect. b. Cow, rabbit: Estradiol enhances the beneficial effect of FSH. c. Rabbit: Prolactin further enhances the effects of estradiol and FSH. d. Human: No evidence is available on the possible synergism between steroids and gonadotropins in enhancing in vitro maturation. It is clear that further research is required to elucidate the mechanisms of action of all the hormones that have been observed to influence oocyte maturation, and to establish the physiologic significance of most of these, particularly in species other than laboratory rodents. Major benefits to animal production and human health are likely to accrue from such research.

Incidence survey of leukemia in China

A nationwide cooperative incidence survey of leukemia was carried out from 1986 to 1988 in a cooperative survey network covering 46 investigating areas. More than 60 million person-years were supervised and 1670 new cases identified. The annual incidence of leukemia was 2.76/10(5), and the 95% confidence interval of the population rate ranged from 2.63/10(5) to 2.89/10(5). The incidences in oil fields and polluted areas were significantly higher than those in other areas. The incidence of acute nonlymphocytic leukemia (ANLL) was 1.62/10(5); acute lymphocytic leukemia (ALL), 0.69/10(5); chronic myelocytic leukemia (CML), 0.36/10(5); chronic lymphocytic leukemia (CLL), 0.05/10(5); and special types, 0.03/10(5). The incidence and constituent ratio of CLL were significantly lower than those in Europe and America. A peak of ALL incidence before age 10 was seen; this rate then declined with increasing age until 30. However, the incidences of other leukemias rose with age, reaching peaks at old age (50-70). The leukemia rate in males was significantly higher than in females, both in youth (10-29) (caused by ALL) and at age old (mainly caused by ANLL). The incidences of ANLL subtypes (including M2b) are reported.

[Isolation and characteristics of Borrelia burgdorferi from Ixodes persulcatus]

We reported the detailed characteristics of Lyme disease spirochetes (Borrelia burgdorferi), strain H7, isolated from Ixodes persulcatus in Heilongjiang. Cells of strain H7 were 9.8--26.5 microns long and 0.13--0.35 microns wide. There were 1--11 waves with a wavelength of 1.2--3.0 microns and an amplitude of 0.59--1.13 microns. Direction of spires was left. Seven flagella were inserted subterminally at each end of the cell and ends were pointed. 31 degrees C was the optimum cultural temperature in vitro. The major constitutional and antigenic proteins were 21k, 32k and 34k proteins. H7 could react on the patient sera of Xinjiang and Heilongjiang with IFA and western blot. These findings demonstrated that strain H7 belonged to species Borrelia burgdorferi, but was a new "subtype" which differed from the strains isolated from other areas and vectors.

[Malondialdehyde-modified-low density lipoprotein in diabetes mellitus]

Malondialdehyde-modified-low density lipoprotein (MDA-LDL), lipid peroxide (LPO), lipid and fasting blood glucose (FBG) were studied in 42 diabetic patients and 20 age-matched controls. The results revealed that both MDA-LDL per L serum and MDA-LDL per mol LDL-C of diabetics were higher than those of controls. MDA-LDL/L tended to be much higher in diabetic patients with vascular disease and hyperlipidemia. There was a positive correlation between MDA-LDL/L and LPO, LDL-C, TC, respectively.

Use of MG series monoclonal antibodies in the diagnosis and experimental targeting therapy of gastric cancer

In order to facilitate early diagnosis and improve the treatment of gastric cancer, 12 murine hybridoma cell lines capable of producing monoclonal antibodies (mAb) against gastric cancer were established. These monoclonal antibodies were used in histopathological diagnosis, cytological and serological diagnosis, and radioimmunoimaging (RII). Also, immunoconjugates and immunoliposomes were produced by linking these antibodies with various anticancer agents. In vitro and in vivo studies in mice were carried out to investigate the possible uses of these antibodies in experimental targeting therapy of gastric cancer. This paper presents a review of these studies.

[Relationship between the bacterial resistance induced by rifamdin and the RNA polymerase]

The results of our experiment in vitro showed that the activity of standard RNA polymerase decreased while the concentration of RFD and RFP increased, indicating that the target site of action of RFD was similar to that of RFP on RNA polymerase. Incorporation of [3H] UR into the RNA of sensitive cells of S. sureus and E. coli was strongly inhibited by RFD, but RFD did not affect the resistant strains. In purified DNA-dependent RNA polymerase of sensitive and resistant strains, the enzyme activity of sensitive E. coli a S. aureus strains was inhibited by RFD, but RFD did not inhibit that of the resistant strains (except the P. vulgaris). It can be concluded that a decreased susceptibility of RNA polymerase to RFD as well as a decreased permeability of bacterial envelope may induce bacterial resistance to the drug.

[Pathological study of 23 cases of nonfunctional pituitary adenoma]

23 cases of nonfunctional pituitary adenoma were studied with light and electron microscopy as well as with immunohistochemical stains PAP technique. Under routine light microscopy, 17 cases were chromophobic adenomas; anyhow, electron microscopy showed that there were 6 cases of oncocytoma; 7 cases of undifferentiated cell adenoma; 4 cases of gonadotropic adenoma; 4 cases of mixed adenomas 1 cases of sparsely granulated GH cell adenoma and 1 case of sparsely granulated PRL cell adenoma. Immunohistochemical stain showed: null cell adenomas 7 cases, FSH cell adenoma 3 cases, LH cell adenoma 1 case, GH cell adenoma 2 cases and other mixed adenoma 10 cases. Therefore, the nonfunctional pituitary adenoma is actually a mixture, and the null cell adenoma was only about 1/3 in this series. Among them, most of the hormones gave no function expression themselves.

Studies on zona hardening in rat oocytes that are matured in vitro in a serum-free medium

The present study confirms that zona pellucidae of rat oocytes became resistant to chymotrypsin digestion (zona hardening) after undergoing in vitro maturation (IVM) in a serum-free medium. However, zona hardening did not occur when empty zonae without oocytes were cultured in the same IVM conditions, suggesting that oocyte-derived factor(s) is responsible for zona hardening in oocytes matured in the serum-free medium. Zona hardening occurred primarily after dictyate oocytes were cultured for 6-8 hours in the IVM medium without serum. Zona hardening could be prevented or alleviated if oocytes were cultured in the IVM medium containing bovine foetal calf serum, a soybean trypsin inhibitor, or beta-mercaptoethanol, and in vitro fertilization rates for such oocytes were normal. Possible mechanisms of the phenomenon of zona hardening in oocytes matured in serum-free conditions are discussed in relation to its possible relevance to the cortical reaction and the physiological block to polyspermy.