Regulation of human cardiac myosin heavy chain genes: the effect of catecholamine

The 5'-flanking regions of the alpha- and beta-cardiac myosin heavy chain (MyHC) genes were excised from the cosmid human genomic clones using Hind III and Xbal for the alpha-MyHC gene, and the Hind III and Hind III sites for the beta-MyHC gene. These fragments were linked to chloramphenicol acetyl transferase (CAT) vector to generate a chimeric fusion gene. These fusion genes were subsequently transfected to neonatal rat cardiac cultured cells to analyze the CAT activity. The alpha-MyHC gene is preferentially expressed as compared to the beta-MyHC. In the presence of norepinephrine (NE) the beta-MyHC gene is remarkably induced (within 24 hours following the addition of norepinephrine to the cardiocyte culture). However, the alpha-MyHC is also induced. Specific alpha andrenergic antagonists such as terazosin (Tz) partially suppressed both the alpha- and beta-MyHC genes as revealed by the CAT activity. These findings suggest that catecholamine does activate the human cardiac MyHC genes but does not differentiate the specific expression of either the alpha- or beta-MyHC genes.

Endothelin stimulates cardiac alpha- and beta- myosin heavy chain gene expression

The effect of endothelin-1 on cardiac myosin heavy chain gene expression was examined using an isolated neonatal rat myocardial cell culture system. The effects of endothelin-1 on the expression of alpha- and beta- myosin heavy chain genes in the primary rat myocardial cell culture system were examined by S1 nuclease protection analysis. Endothelin-1 was found to stimulate both alpha- and beta- myosin heavy chain gene expression. The 5' flanking regions of both the alpha- and beta- myosin heavy chain gene promoters ligated to a reporter gene, chloramphenicol acetyltransferase, were used to study the effect of endothelin-1 on transcription. Myocardial cells treated with endothelin-1 increased the transcription rate of alpha- and beta- myosin heavy chain genes in a dose-dependent manner. Thus, the hypertrophic effect of endothelin-1 on cardiac myocytes involves augmentation of alpha- and beta- myosin heavy chain gene expression by increasing gene transcription.

Prostaglandin E1 and dibutyryl cyclic AMP enhance platelet resistance to deformation

The effect of prostaglandin E1 (PGE1) on platelets is mediated through the PGE1 receptor and the consequent maintenance of the platelet's discoid shape. The effects of PGE1 and dibutyryl cAMP (dbcAMP) on the deformability of human platelets were studied. Deformability tests based upon the micropipette aspiration on the platelets were performed by using pipettes with radii (Rp) of 0.26-0.36 microns. The time course of the extension length (Dp, in microns) of the platelets in response to aspiration with a negative pressure (delta P) of 5 cm H2 O (delta P x Rp = 0.15 dynes/cm) was analyzed. PGE1 treatment (0.1 microM) resulted in a decrease of platelet deformability as compared with results obtained for apparently non-activated, control platelets. The deformation index, i.e., Dp/Rp (PGE1-treated)/Dp/Rp (control), was significantly reduced to 0.90 +/- 0.04. DbcAMP treatment also significantly decreased the deformability of platelets and this decrease was dbcAMP dose dependent. In contrast, colchicine- or cytochalasin D-treated platelets increased deformability. PGE1-treated platelets had a higher [cAMP]i than controls. Platelets treated with PGE1 or dbcAMP showed a reduced [Ca2+]i increment induced by thrombin as compared to non-treated controls. These results indicate that PGE1 and dbcAMP treatment of platelets is accompanied by an enhancement of platelet resistance to deformation. The increased [cAMP]i and low [Ca2+]i after PGE1 treatment may limit the rearrangement of cytoskeleton and thus enhance platelet resistance to deformation.

Interleukin-1 beta induces interleukin-1 alpha messenger ribonucleic acid expression in primary cultures of Leydig cells

Previously, we have reported that interleukin-1 (IL-1) can modulate Leydig cell steroidogenesis. Recently, IL-1-like material has been shown to be present in the testis; however, the cellular source of this material remains unclear. In the present study we found that human recombinant IL-1 beta (1-100 ng/ml) caused dose-dependent increases in IL-1 alpha mRNA expression in Leydig cells. Similar to that reported in other tissues, IL-1 alpha mRNA from Leydig cells is mainly 2.2 kilobases. IL-1 alpha mRNA expression in Leydig cells was detectable as early as 2 h after the addition of IL-1 beta (10 ng/ml) and persisted for up to 24 h. Lipopolysaccharide also stimulated IL-1 alpha mRNA expression in these cells, but phorbol ester had no effect. Our results indicate that Leydig cells are a potential source of IL-1, which has both autocrine and paracrine effects.

[Diaphragmatic fatigue in respiratory distress syndrome in dogs]

Diaphragmatic fatigue (DF) in respiratory distress syndrome (RDS) induced by injection of fat were studied in 7 dogs. After injection of fat, all dogs developed respiratory distress and tachypnea, PaO2 fell to the level lower than 8 kPa. Transdiaphragmatic pressure (Pdi) decreased progressively (P less than 0.05-0.001), Pdi-stimulation frequency (Pdi-F) curve shifted to the right, central frequency (Fc), median frequency (Fm) and high/low frequency ratio (H/L) significantly decreased (P less than 0.05-0.001). It is concluded that the contractile force of the diaphragm progressively decreased after RDS was induced, which suggested the occurrence of DF.

Electrochemical properties of the diiron core of uteroferrin and its anion complexes

The reduction potentials (Em) of the purple acid phosphatase from porcine uterus, uteroferrin (Uf), and its phosphate, arsenate, and molybdate complexes were determined by coulometric methods at various pH values. The midpoint potential of Uf at the pH value for optimal enzyme activity (pH 5) was found to be +367 mV versus a normal hydrogen electrode (NHE), while at pH 6.01 Uf exhibits a reduction potential of +306 mV. At pH 6.01 molybdate was found to shift the potential of Uf more positive by 192 mV, while phosphate and arsenate shift the potential of Uf more negative by 193 and 89 mV, respectively. These shifts are consistent with the different susceptibilities of Uf to aerobic oxidation in the presence of these anions. Comparison of the reduction potential of Uf at pH 7.0 with those reported for other dinuclear non-heme iron enzymes and various (mu-oxo)diiron model complexes suggest that the potential of Uf is too positive to be consistent with a mu-oxo-bridge in Ufo. The pH dependence of the reduction potentials of Uf (60 mV/pH unit) and the fact that the electron transfer rate increases with decreasing pH indicate a concomitant participation of a proton during the oxidation-reduction process. This process was assigned to the protonation of a terminally bound hydroxide ligand at the Fe(II) center upon reduction of Ufo. Structural implications provided by the electrochemical data indicate that molybdate affects the dinuclear core in a manner that differs from that of phosphate and arsenate. This observation is consistent with previous spectroscopic and biochemical studies.(ABSTRACT TRUNCATED AT 250 WORDS)

[Analysis of 70 cases of primary liver carcinoma treated by pu tuo ointment and herbs]

This paper deals with 70 cases of primary liver cancer treated by externally applying Pu Tuo plaster and internally taking oral Chinese herbal medicine. In term of the statistic, of all the cases applied the plaster, 96.7% has proved to be effective in alleviating the pain, 83.5% was remarkable. It has significantly improved the quality of the patients' later lifes. Applying Pu Tuo plaster with taking oral Chinese herbal medicine, the patients could survive longer. On average, after the treatment, the patient could live ten and half months, 44.8% of the II-stage liver cancer patients applied the plaster could live as long as one year, the longest one has been living more than 2 years and 8 months, he looks still well now. He has been working since 1987. In recent B-ultrasonic examination, the patient's primary focus disappeared, and alpha-fetoprotein test turned to be negative.

Regulation of insulin-like growth factor-I messenger ribonucleic acid expression in Leydig cells

In the present study, we evaluated insulin-like growth factor-I (IGF-I) messenger RNA expression in the rat testis. Crude interstitial cells were separated into three distinct bands on 15-60% Percoll density gradients. IGF-I mRNA was mainly localized in the Leydig cell-enriched fraction (band 3), while band 1 and band 2 cells did not contain significant amounts of IGF-I mRNA. Leydig cell IGF-I mRNA consisted of multiple species varying from 0.8 to 7.5 kb and was present in rat Leydig cells all ages examined, from 25 to 55 days old. To further document that IGF-I mRNAs are present in Leydig cells, the method of Klinefelter et al. (Biol. Reprod. (1987) 36, 769-783) was used to isolate highly purified (greater than 98% pure) Leydig cells. Most of the IGF-I mRNA was localized in these Leydig cells, while there was no detectable IGF-I mRNA in the whole testis or other interstitial cells. Furthermore, IGF-I mRNA in Leydig cells was increased more than 2-fold by growth hormone (GH) administration in vivo. This suggests that IGF-I mRNA in Leydig cells is also GH dependent. Interstitial IGF-I produced in Leydig cells may have both autocrine and paracrine effects in the testis.

Transendothelial macromolecular transport in the aorta of spontaneously hypertensive rats

Leaky endothelial junctions occurring during cell turnover have been postulated to be a major pathway for enhanced lipoprotein transport across the vascular endothelial layer, which leads to the development of atherosclerosis. Because hypertension has been well documented as one of the major risk factors for atherosclerosis, we explored the possibility that hypertension accelerates atherogenesis by increasing the turnover of endothelial cells and hence the transendothelial macromolecular permeability. The investigations were performed on thoracic aortas of 10 male 3-4-month-old spontaneously hypertensive rats and eight male age-matched Wistar-Kyoto normotensive rats. In en face preparations of aortic specimens, mitotic endothelial cells were identified by hematoxylin nuclear staining; dying or dead endothelial cells containing cytoplasmic immunoglobulin G were detected by indirect immunoperoxidase technique; and endothelial leakage to Evans blue-albumin conjugate was visualized by fluorescence microscopy. The number of leaky foci per unit endothelial surface area in spontaneously hypertensive rats was found to be approximately three times that in Wistar-Kyoto control rats; the frequencies of both endothelial cell mitosis and death in spontaneously hypertensive rats were also approximately three times the corresponding values in Wistar-Kyoto rats. These findings indicate that hypertension in spontaneously hypertensive rats is accompanied by increased endothelial cell turnover and an attendant enhancement of permeability to macromolecules.

A case of cerebral aspergillosis caused by Aspergillus nidulans. Clinical, pathologic and mycologic identifications

A case of cerebral aspergillosis is reported, the presenting symptom was numbness of right face, which worsened after one year. CT-scan showed two enhanced low-density patches in the anterior and basal parts of right temporal lobe. During operation, an abscess in the deep part of right temporal lobe was revealed. The patient gradually felt amaurosis and oculomotor palsy of right eye. About six months later, she died from intracranial hypertension. Biopsy, as well as autopsy findings suggested fungal infection, and was identified as Aspergillus nidulans, which has probably never been reported in the literature.

Effect of partial discectomy on the stability of the lumbar spine. A study of kinematics

The effect on the stability of the lumbar motion segment, as affected by partial discectomy, was investigated using three-dimensional motion measurement technique. Eight functional spinal units from fresh cadaver lumbar spines were potted and clinically relevant loads applied through a special loading frame attached rigidly to the top vertebra of the specimen. Partial discectomy was performed on the right side of the specimen. The three-dimensional motions of each lumbar motion segment, before and after partial discectomy, were recorded. The results showed that partial discectomy significantly affects the stability of lumbar spinal motion segments. The clinical relevance of this finding is discussed.

Human platelet factor V is crosslinked to actin by FXIIIa during platelet activation by thrombin

Although it has been established that factor V (FV) becomes associated irreversibly with the platelet cytoskeleton after stimulation with thrombin, the chemical nature of this complex is not known. Factor V has recently been demonstrated to be a substrate for factor XIIIa and to form factor V oligomers. We now show that thrombin-activated 125I-FV specifically links to a single protein (43 kDa) of the solubilized platelet membrane in a reaction which requires Ca++ and factor XIIIa. In a purified system, FV, activated by thrombin, forms covalently linked high molecular complexes with 125I-actin catalyzed by factor XIIIa. The site of crosslinking of actin was the factor V fragments, 150 kDa (connecting peptide, C1) and its parent molecule 200 kDa (B). Using radiolabeled actin and unlabeled FV, factor XIIIa catalysed the formation of both homopolymers and heteropolymers. Unlabeled actin was found to compete with radiolabeled FV as a substrate for FXIIIa. To evaluate the biological significance of the crosslinking of factor V to actin, intact platelets were treated with B10 (monoclonal antibody to C1), or monospecific polyclonal antibodies to actin or FXIII. After stimulation with thrombin, the cytoskeleton (material insoluble in Triton X-100) showed markedly decreased 125I-FV in the crosslinked complexes. FV coagulant activity associated with platelet cytoskeleton was also diminished following incubation with an antibody to actin, factor XIII, or B10. These data suggest that FV, through the C1 domain, is crosslinked to actin in the cytoskeleton of thrombin-treated platelets. Activated factor XIII may play a role in plasma FV-platelet interaction as well as the expression of FV derived from the alpha-granules on the cytoskeleton during platelet stimulation.

Interactions between fibrin, collagen and endothelial cells in angiogenesis

The role of fibrin in the generation of new blood vessels was examined in this study. Using a wound chamber model, we investigated the sequential interactions between endothelial cells and the extracellular matrix during angiogenesis. Silicone tubes 5 mm long and 1.4 mm in internal diameter were sutured to the cut ends of thigh muscles in the rats. The contents of the chamber were removed at intervals for histological, immunohistochemical and electron microscopic studies. We observed an initial phase of fluid accumulation in the wound chamber followed by formation of a fibrin/fibronectin clot. Migration of endothelial cells, macrophages and fibroblasts into the clot occurred after the 1st week. The subsequent phase of fibrinolysis was accompanied by deposition of collagen and organization of endothelial cells into capillary tubes. These findings support the view that angiogenesis is the product of interactions between endothelial cells and a changing extracellular matrix (ECM) and requires the participation of soluble and immobilized plasma proteins and local ECM factors. Our findings indicate that fibrin is intimately involved in both hemostasis and angiogenesis; these are sequential steps in the initial phase of wound healing. Thus, fibrin/fibrinogen occupies a central position and provides a vital link in the initiation of the cascade event of wound healing.

Catecholamine and endorphin responses to delivery in term and preterm lambs

A marked increase in catecholamines and endorphins at birth has been described in animals and man. Because the factors which regulate catecholamine secretion are incompletely understood and because it has been suggested that endogenous opiates are important in the regulation of catecholamine secretion, we designed studies to compare changes in plasma catecholamines at birth with simultaneously measured endorphins. Catecholamines and beta-endorphin-like immunoreactivity (beta-ELI) were measured at birth in term (145 days) and preterm (130 days) lambs. Preterm lambs were given natural sheep surfactant intratracheally to prevent respiration failure. Following umbilical cord cutting, there was a marked increase in circulating norepinephrine (NE) and epinephrine (E) levels. The peak preterm NE (2.2 +/- 0.3 ng/ml at 1 h) was greater than the peak term NE (1.0 +/- 0.2 ng/ml at 5 min). The peak preterm E occurred later and also was greater than the peak term E (4.0 +/- 0.5 ng/ml at 1 h vs. 1.3 +/- 0.4 ng/ml at 15 min, respectively, p less than 0.01). Baseline beta-ELI in term animals (767 +/- 15 pg/ml) was greater than preterm (456 +/- 12 pg/ml). Following cord cutting peak beta-ELI in term animals rose to 867 +/- 201 pg/ml compared to a peak beta-ELI in preterm animals of 1,866 +/- 450 pg/ml. These results and their significance for neonatal adaptation to extrauterine life are discussed.

Neonatal adaptation: naloxone increases the catecholamine surge at birth

A marked increase in plasma catecholamines at birth has been described in animals and man. Because the factors that regulate catecholamine secretion are incompletely understood and because it has recently been suggested that endogenous opiates are important in the regulation of catecholamine secretion, we designed studies to determine the influence of opiate receptor blockade prior to delivery on the increase in plasma catecholamines at birth. Term fetal sheep were delivered by cesarean section and randomly assigned to receive naloxone or vehicle. Naloxone was given just prior to umbilical cord cutting as a 2 mg/kg bolus followed by 2 mg/kg/h. Naloxone administration resulted in significantly greater peak levels of plasma norepinephrine (peak levels of 1.5 +/- 0.4 versus 0.9 +/- 0.1 ng/ml) and epinephrine (peak levels of 1.4 +/- 0.7 versus 0.9 +/- 0.3 ng/ml) and higher norepinephrine values throughout the study period. Naloxone administration was associated with significantly elevated heart rate (peak 184 +/- 12 versus 207 +/- 13 beats per min) and blood pressure (peak 95 +/- 6 versus 88 +/- 2 mm Hg). These studies demonstrate that opiate receptor blockade from birth markedly augments the neonatal sympathoadrenal response in the term newborn lamb.

An ethanol/ether soluble apoprotein from rat lung surfactant augments liposome uptake by isolated granular pneumocytes

Ethanol/ether soluble apoproteins, comprising 17% of the total recovered surfactant-associated proteins, were isolated from rat lung surfactant and purified by silicic acid chromatography. The protein that eluted in 4:1 chloroform/methanol accounted for greater than 85% of protein in the ethanol/ether soluble fraction and was termed surfactant apoprotein Et (Apo Et). By sodium dodecyl sulfate polyacrylamide gel electrophoresis, this protein had an apparent molecular weight of approximately 10,500. Apo Et was evaluated for its effect on uptake of synthetic phospholipids in liposomal form by isolated granular pneumocytes (Type II alveolar epithelial cells) in primary culture. Liposomes were prepared to approximate the phospholipid composition of the alveolar surfactant, and uptake was measured by the accumulation of the radioactively labeled dipalmitoyl phosphatidyl choline fraction. The uptake of liposomal phosphatidylcholine by cells incubated for 2 h with Apo Et was increased by 61% over control. Most of the cell-associated phospholipid uptake was resistant to treatment with trypsin, suggesting an increased internalization of liposomal material in the presence of Apo Et. The effect of Apo Et on uptake was concentration and time dependent and was not associated with cell damage, phospholipase activity, or detergent properties of the protein. Apo Et had no significant effect on phosphatidylcholine uptake by granular pneumocytes maintained for 7 d in primary culture. Apo Et augmented the uptake of phospholipids by alveolar macrophages although total uptake by these cells was less than that observed with granular pneumocytes. Because Apo Et increases the rate of uptake of surfactant phospholipids by alveolar cells (granular pneumocytes and alveolar macrophages), this protein may represent a physiologically important regulator for clearance of lung surfactant phospholipids.

Studies on the half-life and the distribution of stearoyl-CoA desaturase in the housefly

The half-life of the stearoyl-CoA desaturase was determined by using houseflies injected with puromycin. The LD50 for puromycin was determined to be 1.55 micrograms/mg body wt for both sexes. By following the decay in specific activity of the desaturase after puromycin injection, the half-life of this enzyme in 4-day-old females was calculated to be 9.35 hr, while in 1-day-old females it was 3.38 hr. The inhibition curve for the 3-day-old males never reached 100%, and a biphasic curve was observed. The early phase resulted in a half-life of the desaturase of 2.41 hr, while the latter phase had a half-life of 8.45 hr. In general, it appeared that the half-life of the desaturase increased with age in either sex. Studies on the distribution of desaturase activity within the housefly showed that most of the activity was present in the integument; however, in the female, the onset of ovarian development seemed to shift the distribution of desaturase from the integument, towards the internal tissues. In the male, there appeared to be equal amounts of desaturase in integument and the fat body plus internal tissues at day 2, but by day 5 most of the activity was associated with the integument. The high specific activity and high percentage of total desaturase activity associated with integument coupled with the shift of distribution of desaturase in females during the onset of ovarian development may be indicative of a close correlation of the desaturase with alkene synthesis and possibly sex pheromone production.

Ethanol ingestion and polyunsaturated fatty acids: effects on the acyl-CoA desaturases

The ingestion of ethanol results in altered compositions of the polyenoic fatty acids in a variety of liver and brain membranes. A possible cause for these alterations in hepatic endoplasmic reticulum membranes has been studied by measuring the delta 9, delta 6, and delta 5 acyl-CoA desaturase activities in hepatic microsomes from chronically or acutely treated rats. Chronically, ethanol decreased all three enzyme activities with the following order of sensitivity: delta 6 (65%), delta 9 (54%), and delta 5 (46%). The short-term study indicated that all three desaturase activities were affected after 1 day of ethanol feeding. NADPH- and NADH-cytochrome c reductase activities were found to be reduced in chronically treated rats, and the NADH-cytochrome c reductase was decreased in the acutely treated. However, these reduced enzyme activities could not account for the decrease in desaturase activities due to the very marked differences between the specific activities of these enzymes compared to the desaturase. Thus, we conclude that changes in membrane polyenoic fatty acid composition can be result of ethanol-induced decreases in the terminal desaturase enzymes.