[Regulation of G protein-coupled receptor kinase activity]

Recent progress on the activation of G protein-coupled receptor kinases is reviewed. beta-Adrenergic receptor kinase (beta ARK) is activated by G protein beta gamma -subunits, which interact with the carboxyl terminal portion of beta ARK. Muscarinic receptor m2-subtypes are phosphorylated by beta ARK1 in the central part of the third intracellular loop (I3). Phosphorylation of I3-GST fusion protein by beta ARK1 is synergistically stimulated by the beta gamma -subunits and mastoparan or a peptide corresponding to portions adjacent to the transmembrane segments of m2-receptors or by beta gamma -subunits and the agonist-bound I3-deleted m2 variant. These results indicate that agonist-bound receptors serve as both substrates and activators of beta ARK.

Focal spasms in clusters, focal delayed myelination, and hypsarrhythmia: unusual variant of West syndrome

We report a patient who began to have clusters of seizures characterized by brief elevation of the right arm at 6 months of age. An interictal electroencephalogram (EEG) at 7 months revealed hypsarrhythmia without definite asymmetry. Simultaneous EEG and video recording disclosed that these focal spasms were associated with fast wave bursts superimposed on slow waves most markedly in the left centro-midtemporal region. The patient became seizure-free after synthetic ACTH therapy. The patient is developmentally normal at 3 years 5 months, but magnetic resonance imaging studies revealed findings suggestive of delayed myelination in the left frontal region. This patient is considered to have had an unusual variant of West syndrome associated with focal delayed myelination.

Synergistic activation of a G protein-coupled receptor kinase by G protein beta gamma subunits and mastoparan or related peptides

Muscarinic acetylcholine receptors (mAChR, m2 subtype) are phosphorylated in an agonist-dependent manner by a G protein-coupled receptor kinase (GR kinase) at sites located in the central part of mAChR. The GR kinase phosphorylated a glutathione S-transferase fusion protein containing the m2 phosphorylation sites (13-GST). Phosphorylation of 13-GST was markedly stimulated by mastoparan: the Km for 13-GST decreased from 7.3 to 0.17 microM in the presence of 100 microM mastroparan and the Vmax increased 23-fold. beta gamma Subunits of G proteins synergistically stimulated the phosphorylation of 13-GST in the presence of 1-10 microM mastoparan by increasing the affinity of mastoparan for the GR kinase. The phosphorylation of mAChR by the GR kinase was also synergistically stimulated by 1-10 microM mastoparan in the presence of beta gamma subunits, but was inhibited by 100 microM mastoparan. Similar stimulatory and inhibitory effects on the phosphorylation of 13-GST and mAChR were observed using synthetic peptides of 15-20 amino acid residues corresponding to sequences of intracellular segments adjacent to the transmembrane segments of mAChR. These results are consistent with and support the idea that the GR kinase is synergistically activated by both G protein beta gamma subunits and agonist-bound receptors.

Location of agonist-dependent-phosphorylation sites in the third intracellular loop of muscarinic acetylcholine receptors (m2 subtype)

Muscarinic acetylcholine receptors (mAChR, human m2 subtype) expressed in Sf9 (Spodoptera frugiperda) cells using the baculovirus system were purified and subjected to phosphorylation by a mAChR kinase, which was partially purified from porcine cerebrum. Two bands with apparent molecular masses of 59 kDa and 39 kDa as determined by SDS/PAGE were found to be phosphorylated in an agonist-dependent manner. Both bands were labeled by the irreversible muscarinic ligand [3H]propylbenzilylcholine mustard. Molecular masses of the [32P]phosphorylated or [3H]propylbenzilylcholine-mustard-labeled bands decreased following treatment with N-glycanase. The 59-kDa and 39-kDa bands were converted to 52-kDa and 32-kDa bands, respectively, indicating that both the 59-kDa and 39-kDa bands contain the amino-terminal region where glycosylation sites are present. The ratio of incorporated [32P]phosphate and bound [3H]propylbenzilylcholine mustard was essentially the same for the 59-kDa and 39-kDa bands, indicating that all the phosphorylation sites reside in the sequence of 39 kDa from the amino-terminal region. The amounts of incorporated [32P]phosphate were estimated to be 10-11/receptor, with 7-8 serine and 3-4 threonine, but no phosphorylated tyrosine residues. Further treatment of [32P]phosphorylated or [3H]propylbenzilylcholine-mustard-labeled receptors with V8 protease indicated that the phosphorylation sites were not present in 30-kDa amino-terminal segment. These results indicate that the phosphorylation sites are localized in the range 30-39 kDa from the amino terminus, which consists of primarily the central part of the third intracellular loop. Consistent with this conclusion, a fusion protein containing glutathione S-transferase linked to a peptide corresponding to residues 227-324 of the central part of the third intracellular loop was found to be phosphorylated by the mAChR kinase in a heparin-sensitive manner.

G protein-mediated inhibition of phosphoinositide metabolism evoked by metabotropic glutamate receptors in frog oocytes

1. Metabotropic glutamate receptor subtype 1 (mGluR1), when expressed in Xenopus oocytes, activates phosphoinositide-specific phospholipase C (PLC) in a G protein-dependent manner. This reaction results in the activation of chloride channels in the oocytes, and can be monitored electrophysiologically. We expressed different G protein alpha-subunits together with mGluR1 in oocytes, and examined the effects of these G protein subunits on the PLC-mediated reaction. 2. The expression of the alpha-subunit of GL2, a bovine version of G11, which is a member of the Gq subgroup, potentiated the mGluR1-evoked reaction, whereas the alpha-subunit of GL1, a bovine G14, which is also a member of the Gq subgroup, strongly suppressed it. The expression of Gs alpha also suppressed this reaction. 3. We then expressed G beta 1 gamma 2-subunits in addition to the G alpha-subunits, and examined the mGluR1-evoked reactions. Both the potentiation and suppression by GL2 alpha and GL1 alpha, respectively, were more pronounced in the presence of the G beta 1 gamma 2-subunits. In contrast, the suppression by Gs alpha was completely reversed by G beta 1 gamma 2. 4. The direct activation of G proteins by the intracellular injection of either fluoride ions or guanosine-5'-O-(3-thiotriphosphate) (GTP gamma S) causes similar PLC-mediated reactions. The expression of GL2 alpha, GL1 alpha or Gs alpha caused potentiation, suppression and no change, respectively, on the fluoride- (or GTP gamma S-) evoked reactions.(ABSTRACT TRUNCATED AT 250 WORDS)

Large-area, high-resolution pattern replication by the use of a two-aspherical-mirror system

A soft-x-ray projection lithography system is developed by the use of multilayer mirrors. To determine the feasibility of a high throughput and a large exposure area, we developed a reduction system that consists of two-aspherical-mirror optics. The figure errors of aspherical mirrors are evaluated by a laser interferometer. The rms aspherical figure errors of concave and convex mirrors are 8.8 and 2.0 nm, respectively, which are not enough to yield a resolution of 0.1 µm. The reduction optics is constructed by adjusting the mirror position to compensate for aberrations, and some trial replications are performed. An exposure area of larger than 10 mm × 0.6 mm with a fine pattern of less than a quarter micrometer is achieved.

[A survey of the initial course of tuberculosis chemotherapy under compulsory hospitalization on the basis of the revised Tuberculosis Prevention Law--report of the 32nd C series of controlled trials of chemotherapy--Cooperative Study Unit of Chemotherapy of Tuberculosis of the National Sanatoria in Japan]

We studied 2247 patients with pulmonary tuberculosis who were hospitalized for the initial course of chemotherapy under the provision of the revised Tuberculosis Prevention Law issued by Japanese Ministry of Welfare. The results were as follows. 1) There were more males than females with a ratio of 2.6: 1. 2) There were two peaks in their ages, 20s and 60s. 3) The average admission periods were 5.2 +/- 2.7 months for men and 5.1 +/- 2.8 months for women. 4) The average compulsory admission periods were 6.8 +/- 2.5 months for men and 6.4 +/- 2.3 months for women, so that the actual admission periods were shorter in the majority of the patients. 5) The sputum cultures were converted negative in three months in about 80 percent of the patients who were smear and/or culture positive on admission. 6) The appearance rate of INH-resistant and RFP-resistant strains were 2% and 1.4% respectively. 7) Most of the death from tuberculosis was observed in the early stages of admission. 8) With regards to the cost, there seemed to be no difference whether treated under the new or the old provisions. 9) The newly approved extension of the admission periods for those who had complications such as diabetes mellitus or pneumoconiosis and those who had INH and/or RFP positive bacilli seemed to be appropriate.

The effect of acarbose on blood glucose profiles of type 2 diabetic patients receiving insulin therapy

Nine patients with Type 2 diabetes receiving insulin therapy were treated with acarbose 100 mg thrice daily for 1 week to investigate the effect of acarbose on blood glucose control. Daily blood glucose profiles contained fewer excursions during acarbose administration and low levels were maintained. The M-value, an indicator of blood glucose fluctuation, decreased significantly from a run-in period value of 37.6 +/- 8.7 (SEM) to 16.7 +/- 4.0 during the acarbose period (p < 0.05) and rose again to 28.9 +/- 6.7 (p > or = 0.05) in the follow-up period. The 24-h urinary glucose excretion similarly decreased during acarbose administration. As expected, no decrease in HbA1C was observed due to the short treatment period. The 24-h urinary C-peptide excretions and serum lipids were not influenced by acarbose therapy. Frequent episodes of clinical hypoglycaemia were experienced while on acarbose therapy, indicating a decrease in insulin requirements. Adverse events such as flatulence and abdominal distention were observed in six out of nine cases. Symptoms were generally mild and well tolerated, only one patient dropped out because of diarrhoea and abdominal pain. We conclude that acarbose could usefully be administered to Type 2 diabetic patients treated with insulin to improve blood glucose control and reduce insulin requirement if the appropriate selection criteria were met.

Activation by G protein beta gamma subunits of beta-adrenergic and muscarinic receptor kinase

We have shown previously that GTP-binding regulatory protein (G protein) beta gamma subunits stimulate the agonist- or light-dependent phosphorylation of muscarinic acetylcholine receptors (mAChRs) and rhodopsin by a protein kinase partially purified from porcine brain (mAChR kinase) but not the phosphorylation of rhodopsin by rhodopsin kinase (Haga, K., and Haga, T. (1992) J. Biol. Chem. 267, 2222-2227). We report here that the mAChR kinase phosphorylates beta-adrenergic receptors (beta-ARs) purified from bovine lung in an agonist-dependent manner, and the phosphorylation is also stimulated by G protein beta gamma subunits. We also report that recombinant beta-adrenergic receptor kinase 1 (beta-ARK1) expressed in COS-7 cells phosphorylates mAChRs (human m2 subtype) and rhodopsin in an agonist- or light-dependent manner, respectively, and that this phosphorylation is stimulated by G protein beta gamma subunits. By contrast, the beta gamma subunits do not stimulate the phosphorylation of mAChRs or rhodopsin by a beta-ARK1 mutant lacking a part of the carboxyl-terminal region which is present in beta-ARKs but not in rhodopsin kinase. These results indicate that the beta-ARK1 is the same as or very similar to the mAChR kinase but is distinguished from the rhodopsin kinase with respect to activation by the beta gamma subunits and that the extra carboxyl-terminal sequence in beta-ARKs is required for the stimulation by the beta gamma subunits.

Improved oral absorption of a poorly water-soluble drug, HO-221, by wet-bead milling producing particles in submicron region

N-[[[4-(5-Bromo-2-pyrimidinyloxy)-3-chlorophenyl]amino]carbonyl]-2 -nitrobenzamide (HO-221) is being developed as an anticancer agent with a novel mode of action. HO-221 shows poor oral absorption and is only slightly soluble in water (0.055 micrograms/ml at 37 degrees C). In this study, it was shown that the reduction in particle size of HO-221 to the submicron region (0.453 microm, mean by volume) could be achieved by a wet milling in a decaglycerin monolaurate aqueous solution with small glass beads. The wet milling suspension obtained showed improved dissolution rate and oral absorption in rats. A solid dosage form could also be made from that suspension with addition of sucrose palmitate which prevented aggregation caused by the hydrophobic interaction. The solid dosage form thus obtained showed twice as much oral absorption in dogs as the preparation made by dry milling.

Solubilization and characterization of atrial muscarinic acetylcholine receptors in sucrose monolaurate

Muscarinic acetylcholine receptors (mAChRs) can be solubilized from porcine atrial membranes in sucrose monolaurate (SM-1200) with retention of up to 80% of N-[3H]methylscopolamine ([3H]NMS) binding activity. The mAChRs solubilized by SM-1200 were relatively stable at 4 degrees C with an estimated half-life (tau 1/2) of the ligand binding activity of 19 days. Inactivation of the ligand binding activity is dependent on the incubation temperature, and tau 1/2 was estimated to be 5.7 h at 20 degrees C, 28 min at 30 degrees C, and less than 1 min at 45 degrees C. The activation energy of the receptor inactivation was estimated to be 199 kJ/mol. Ligand binding characteristics of SM-1200-solubilized mAChRs were similar to those of digitonin/cholate-solubilized receptors. Sucrose density gradient centrifugation revealed a single peak with an apparent sedimentation coefficient of 5.7 S. The solubilized atrial mAChRs were purified approximately 1000-fold by using affinity chromatography with aminobenztropine as the ligand. The purified mAChRs were reconstituted with GTP binding regulatory proteins (G(o)) in lipid vesicles, and the reconstituted vesicles showed guanine nucleotide-sensitive, high-affinity agonist binding and agonist-stimulated GTP gamma S binding in the presence of GDP. Thus, sucrose monolaurate is a new detergent in which mAChRs can be solubilized in stable form with high yield and purified up to 1000 times with retention of the binding activity with muscarinic ligands and G-proteins.

[A case of spontaneous bacterial peritonitis with ascites caused by hypoproteinemia after a massive bleeding from a gastric ulcer]

A case of spontaneous bacterial peritonitis (SBP) developed in an old man whose ascitic fluid was related neither to portal hypertension nor nephrotic syndrome, but with severe hypoalbuminemia emerged after a massive bleeding from a gastric ulcer in a malnutrition state. Ascitic fluid, increasing day by day, yielded Enterobacter cloacae and Bacteroides fragilis. Though autopsy was not carried out because of refusal of his family, neither liver necropsy, nor abdominal CT scan nor repeated abdominal ultrasonography showed findings suggesting existence of liver cirrhosis. In the presence of his ascites, the extent of a chemiluminescence (CL) response of polymorphonuclear cells from volunteers was significantly lower than that of his serum. This report shows that SBP can develop in a patient with ascites unrelated to portal hypertension when ascitic fluid induces little CL response.

Phosphorylation of muscarinic receptors: regulation by G proteins

Effects of G proteins on the phosphorylation of muscarinic receptors (mAChRs) have been examined. Cerebral but not atrial mAChRs were phosphorylated by any one of three types of protein kinase C and 4-6 mol of phosphate were incorporated per mol of mAChR, mostly in the 12-14 kDa from the carboxyterminus. Atrial mAChRs were better substrates of cAMP-dependent protein kinase than cerebral mAChRs. Phosphorylation of mAChRs by protein kinase C or cAMP-dependent protein kinase was not dependent on the presence of agonists and G proteins except that a slight inhibition by G proteins was observed probably because G proteins were also substrates of the two kinases. Agonist-dependent phosphorylation of atrial mAChRs or recombinant human mAChRs (m2 subtype) by a kinase (mAChR kinase), which is the same or very similar to beta adrenergic receptor kinase (beta ARK), was found to be regulated by the G proteins in a dual manner; stimulation by G protein beta gamma subunits and inhibition by G protein alpha beta gamma trimer. The inhibition by the G protein trimer is restored by addition of guanine nucleotides and is considered to be due to the formation of a ternary complex of agonist, mAChR and guanine nucleotide free G proteins. The stimulation by G protein beta gamma subunits was also observed for the light- or agonist-dependent phosphorylation of rhodopsin and beta AR by the mAChR kinase but not for the light-dependent phosphorylation of rhodopsin by rhodopsin kinase. The phosphorylation by beta ARK 1 was also found to be stimulated by G protein beta gamma subunits. The beta gamma subunit is considered to interact with the extra 130 amino acid residue carboxyterminal tail of beta ARK, which does not exist in rhodopsin kinase, and the interaction results in the activation of the kinase. We may assume that the G protein coupled receptor kinase is an effector of G protein beta gamma subunits and that one of the functions of beta gamma subunits is to stimulate the phosphorylation of G protein coupled receptors thereby facilitating their desensitization.

Effects of magnesium ion on the interaction of atrial muscarinic acetylcholine receptors and GTP-binding regulatory proteins

Muscarinic acetylcholine receptors (mAChR) purified from porcine atrium were reconstituted into lipid vesicles with GTP-binding regulatory proteins (G proteins, Gi, Go, or Gn) purified from porcine cerebrum. Apparent affinities of the reconstituted mAChR and G proteins for carbachol and GDP, respectively, were estimated from the effects of these ligands on the binding of [3H]-L-quinuclidinyl benzilate ([3H]QNB) to mAChR and [35S]guanosine 5'-O-(3-thiotriphosphate) ([35S]GTP gamma S) to G proteins in the presence of different concentrations of MgCl2. A total of 30-35% of reconstituted mAChRs exhibited low affinity for carbamylcholine, irrespective of the presence or absence of guanine nucleotides, and the remainder of the mAChRs showed high affinities for carbamylcholine in the absence of GTP or GDP and a low affinity in their presence. The affinity for carbamylcholine in the absence of guanine nucleotides, but not in their presence, increased with increases in MgCl2 concentration. Apparent Kd's for carbamylcholine were estimated to be approximately 100 microM in the presence of guanine nucleotides, 1.5 microM in the absence of guanine nucleotide and Mg2+ (< 0.1 microM), and 0.1 microM in the absence of guanine nucleotide and the presence of MgCl2 (10 mM). These results indicate that mAChRs may assume at least three different conformations that are characterized by different affinities for agonists. Furthermore, the data suggest that MgCl2 is not necessary for the formation of the mAChR-G protein complex, but can induce a conformational change in the complex. On the other hand, the presence of MgCl2 was necessary for carbamylcholine to influence the binding of guanine nucleotides.(ABSTRACT TRUNCATED AT 250 WORDS)

[Recent technical advances in portable oxygen delivery systems]

According to a Japanese national survey (June 30, 1990), the number of patients receiving home oxygen therapy (HOT) has been greater than 18,000 since March 1985, when HOT was first covered by health insurance. The oxygen concentrator, especially the molecular sieve type, is the most common method of delivery (more than 90%). In April 1988, the portable oxygen cylinder was acknowledged by health insurance, and the liquid oxygen supply system in April 1990. Three types of portable oxygen delivery systems are available; oxygen cyclinder, liquid oxygen system, and oxygen concentrator (membrane type), of which the oxygen cylinder is most commonly used. In our hospital, portable oxygen supply systems were used in 80% of 168 HOT cases in 1990, and the use of 400 L aluminum oxygen cylinders at a flow rate of 1-2 L/min has been most popular. There is an strong desire from patients for lighter portable oxygen supply system of longer duration. In 19 patients with chronic respiratory failure, we evaluated a newly designed demand oxygen delivery system (DODS), which weighs 2.4 kg including the DOD device (TER-20 Teijin), 1.1 L oxygen cylinder made of ultressor, nasal cannula, and carrier. Arterial blood gases at rest (room air) were PaO2 61.9 +/- 6.3 torr, PaCO2 63.8 +/- 9.4 torr and pH 7.40 +/- 0.04. A crossover trial was performed under three conditions; breathing room air with no weight, and pulse oxygen flow and continuous oxygen flow each carrying 2.4 kg of weight. Both 6 minute walking (E1) and walking on a slow speed treadmill (E2) were studied.(ABSTRACT TRUNCATED AT 250 WORDS)

MR imaging of chronic alcoholism

We evaluated the brain lesions of patients with chronic alcoholism (n = 34) in comparison with age- and sex-matched controls (n = 40) by MR imaging. T1-weighted sagittal and axial images and T2-weighted axial images were obtained with a 0.5 T superconducting MR unit. Various brain measurements were then performed, and the presence of regions of abnormal signal intensity was also compared between the two groups. The brain measurements revealed significant cerebral atrophy (characterized by lateral and 3rd ventricular dilatation, and widening of the interhemispheric fissure) as well as significant cerebellar atrophy (represented by 4th ventricular dilatation) in the alcoholic group. These changes were more prominent in patients in their fifties and sixties than in those aged in the thirties and forties. Focal hypointense lesions were observed in 20.6% of the alcoholics and in 5% of the controls (p less than 0.01), while focal hyperintense lesions were observed in 61.8% of the alcoholics and in 20% of the controls (p less than 0.001). The severity of these MR findings correlated well with the age of the patients. These observations suggest that alcohol is an important promoter of brain aging.

Molecular analysis of virus-producing and non-producing clones derived from a defective SSPE virus Yamagata-1 strain

Two virus clones were isolated from a defective SSPE virus, the Yamagata-1 strain, and designated as the YA and YF clones. The YA clone-infected cells produced neither cell-free virus nor cell-associated virus, whereas the YF clone-infected cells produced both cell-associated and cell-free virus. No difference of epitopes on structural proteins was observed between these two clones. Both clones had hemadsorption activity. Quantitation of structural protein by Western dot blots showed relatively a lower amount of M protein in the YA-infected cells than that in the YF-infected cells. The ratio, P plus M dicistronic/M monocistronic mRNA, in the YA-infected cells was about twice that in the YF-infected cells. Sequence analysis of cDNA corresponding to P plus M dicistronic mRNA revealed that the deduced M protein of the YF virus was smaller than that of the YA virus by five amino acids from the carboxy terminal. These results suggest that abundant production of P plus M dicistronic mRNA is responsible for the reduced amount of M protein in the non-productive YA clone.

[Silicone breast implants and collagen diseases]

Connective tissue disease has been reported to occur following implantation of silicone gel-filled prostheses to augment the breast. In this case report and review of the literature, two patients are described in whom connective tissue disease developed within one and three years respectively after cosmetic surgery. One developed dermatomyositis with lung fibrosis, and the other developed cutaneous lupus and a Sjögren-like syndrome. Both suffered serious complications due to vasculitis. Although evidence of a causal relationship between the implantation and the development of connective tissue disease is circumstantial, removal of the silicone prosthesis has been reported to result in subsequent remission.

Complete nucleotide sequence of the phosphoprotein of the Yamagata-1 strain of a defective subacute sclerosing panencephalitis (SSPE) virus

The complete nucleotide sequence of the phosphoprotein (P) gene of the Yamagata-1 strain of a defective subacute sclerosing panencephalitis (SSPE) virus was determined. Comparison with the P gene of the Edmonston strain of measles virus (MV) revealed 44 differences of which 23 nucleotides substitutions were identical with those revealed between other SSPE viruses and MV (Cattaneo et al. (1989) Virology 173, 415-425). The consensus sequence of the G insertion site was completely conserved, whereas mRNAs with one or three non-templated G residue insertions were found in addition to the mRNA of the exact genome copy. As a result of the frameshift downstream of the site of G insertion, the cysteine-rich V protein was predicted from the one G-inserted mRNA besides the P and C proteins predicted from the genome-copied mRNA.

Activation by G protein beta gamma subunits of agonist- or light-dependent phosphorylation of muscarinic acetylcholine receptors and rhodopsin

We have partially purified a protein kinase that phosphorylates muscarinic receptors (mAChR) in the presence of agonists and have shown that the phosphorylation is stimulated by the beta gamma subunits of the GTP binding protein Go (Haga, K., and Haga, T. (1990) FEBS Lett. 268, 43-47). We report here that rhodopsin is also phosphorylated in a light-dependent manner by the same kinase preparation and that beta gamma subunits derived from Gs, Gi, and Go stimulate the phosphorylation of both rhodopsin and mAChRs. The rhodopsin- and mAChR-phosphorylating activities were eluted in the same fractions using a purification procedure that is essentially the same as that used for the purification of beta-adrenergic receptor kinase (Benovic, J.L., Strasser, R.H., Caron, M.G., and Lefkowitz, R.J. (1986) Proc. Natl. Acad. Sci. U. S. A. 83, 2797-2801) and were inhibited by low concentrations of heparin, an inhibitor of beta-adrenergic receptor kinase, (IC50 = 15 nM), suggesting that both mAChR and rhodopsin are phosphorylated by the same or very similar kinase(s) belonging to the beta-adrenergic receptor kinase family. G protein beta gamma subunits increased the Vmax of the phosphorylation of rhodopsin 12-fold. Kinetic data were consistent with the assumptions that the protein kinase (mAChR kinase) binds rhodopsin and beta gamma subunits in a random order and that the reaction rate is proportional to concentration of the ternary complex. By contrast, the light-dependent phosphorylation of rhodopsin by the rhodopsin kinase was not stimulated by the beta gamma subunits. These results indicate that beta gamma subunits may interact with and activate the mAChR kinase but not rhodopsin kinase and suggest that the beta gamma subunit of G proteins may take part in the desensitization of G protein-linked receptors.

[Mycobacterium examination system at the National Jewish Center in the States]

Impressions on visit to Mycobacteriology Laboratory of National Jewish Center for Immunology and Respiratory Medicine are reported. The BACTEC and Gen-Probe Method are introduced to the laboratory system on mycobacterial examinations such as detection, identification, drug susceptibility and minimal inhibitory concentration test.

Synthesis and antitumor activities of novel benzoylphenylurea derivatives

Seventy novel benzoylphenylurea compounds were synthesized and their antitumor activities were examined in vivo against P388 leukemia. N-(2-Nitrobenzoyl)-N'-[4-(2-pyrimidinyloxy)phenyl]ureas showed the highest antitumor activities when dosed intraperitoneally or orally. Their structure-activity relationships were examined with particular focus on the position and the variety of substituent on each aryl ring.

Identification of two novel GTP-binding protein alpha-subunits that lack apparent ADP-ribosylation sites for pertussis toxin

Molecular cloning of cDNAs encoding alpha-subunits of guanine nucleotide-binding regulatory proteins (G-proteins) has revealed the existence of nine species of alpha-subunits. We have identified two additional G-protein alpha-subunits, which we refer to as GL1 alpha and GL2 alpha, by isolating bovine liver cDNA clones that cross-hybridized at reduced stringency with bovine Gi1 alpha-subunit cDNA. The deduced amino acid sequences of GL1 alpha and GL2 alpha share 83% identity with each other and show 45-55% identity with those of other known G-protein alpha-subunits. Both GL1 alpha and GL2 alpha lack a consensus site for ADP-ribosylation by pertussis toxin. Messenger RNA corresponding to GL2 alpha was detected in all tissues examined, but GL1 alpha mRNA was detected only in liver, lung, and kidney. Antiserum prepared against a synthetic pentadecapeptide corresponding to the deduced carboxyl terminus of GL2 alpha specifically reacted with a 40-kDa protein in mouse liver, brain, lung, heart, kidney, and spleen. The amount of the 40-kDa protein was highest in brain and lung. We suggest that GL1 alpha and GL2 alpha are new members of a subfamily of pertussis toxin-insensitive G-proteins.

[What has tuberculosis medical care contributed to modern medicine in Japan]

About 40 years ago, we had a huge number of tuberculosis patients which were about three to five millions. And a great deal of effort has been given in order to conquer tuberculosis. The philosophy and the technology used in there efforts are thought to have made considerable contributions to the development of modern medicine in other fields in Japan. The controlled clinical trial used to test new antituberculous agents has been a basis for a modern judgment on the effectiveness of any new drugs and it has brought good clinical practices. Scientific procedures for diagnosis, bronchoscopy and pulmonary function tests started in the field of tuberculosis to have more detailed diagnosis included differential one, preoperative evaluation, and evaluation for respiratory failure. Philosophy and methods of modern rehabilitation for the patients started from the care for the patient with pulmonary tuberculosis. Occupational therapy has been used for confirmation of curability of tuberculosis and restoration of the physical strength. Physiotherapy also started from exercises preventing deformities of the thorax after thoracoplasty. Terminal care for patients with cancer and other incurable diseases is now most new medical way, but in the field of tuberculosis before chemotherapeutic era, these were good experiences for this kind of care. A pain control using morphine or cocaine for spinal caries and laryngeal tuberculosis, and also telling the truth to the patients were the good examples. Holistic medicine, which is also a modern topic, has been considered in tuberculosis medical care, because the disease has so much psycho-social problems.(ABSTRACT TRUNCATED AT 250 WORDS)

Interaction of deglycosylated muscarinic receptors with ligands and G proteins

Endoglycosidase F was used to investigate the role of the carbohydrate moiety of muscarinic acetylcholine receptors in antagonist and agonist binding, and the interaction with G proteins. The receptors were purified from porcine cerebrum, treated with endoglycosidase F and then covalently labeled with [3H]propylbenzilylcholine mustard [( 3H]PrBCM). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the [3H]PrBCM-labeled receptors showed that the endoglycosidase F treatment caused a decrease in apparent Mr from 70 to 51 kDa, the Mr predicted for the peptide portions of M1, M2 and M4 subtypes. Endoglycosidase F-treated receptors had essentially the same affinities for both agonists and antagonists as those of control receptors. In addition, treated receptors that had been reconstituted in lipid vesicles with G proteins showed guanine nucleotide-sensitive high affinity for agonists. These results suggest that the carbohydrate moiety of muscarinic acetylcholine receptors is not involved in their interaction with muscarinic ligands and G proteins.

[Usefulness of demand oxygen delivery system for patients with chronic respiratory failure due to mainly tuberculosis sequelae]

To evaluate the usefulness of a new oxymatic conserver, Demand Oxygen Delivery System (DODS), we compared DODS breathing with Standard steady flow (SF) breathing in thirteen subjects with chronic respiratory failure due to mainly tuberculosis sequelae. The value of the DODS (Oxymatic) is that it delivers oxygen only during early inspiration, so as to minimize loss from delivery during expiratory phase. Improvement of SaO2, measured by BIOX 3740, and PaO2 were observed at rest and on exercise. The oxygen consumption ratio of the DODS to the SF method was between 0.5 and 0.3, favoring the DODS over the SF method. In some patients DODS hardly ran at rest. But no problems are observed during exercise. The results indicate the effectiveness of DODS in advancement of quality of life patients with chronic respiratory failure.

The interaction of acetylcholine receptors in porcine atrial membranes with three kinds of G proteins

We developed a simple procedure to detect the interaction of muscarinic receptors in atrial membranes with exogenous GTP-binding proteins (G proteins). The procedure consists of mixing atrial membranes with G proteins in the presence of sodium cholate, diluting the mixture with a salt buffer and then measuring the ligand binding activity. The displacement by carbachol of [3H] QNB binding to muscarinic receptors in the atrial membranes was not affected by guanine nucleotides when the membranes had been treated at 60 degrees C for 30 min or with N-ethylmeleimide (NEM) and became affected by them after mixing the heat- or NEM-treated membranes with G proteins. The displacement curves in the presence of GTP were essentially the same irrespective of the presence or absence of G proteins. Those in the absence of GTP shifted to a lower concentration of carbachol with addition of a higher concentration of G proteins, indicating an increase in GTP-sensitive high affinity agonist binding sites. The highest affinity for carbachol was detected with membranes treated with NEM and then mixed with G proteins. The GTP-sensitive high affinity agonist binding could be detected with any one of three kinds of G proteins (Gi, Go, Gn) which were purified from porcine cerebrum, indicating that the muscarinic receptor m2 subtype may interact with and possibly activate these three kinds of G proteins.

Dual regulation by G proteins of agonist-dependent phosphorylation of muscarinic acetylcholine receptors

Muscarinic acetylcholine receptors purified from porcine atrium were phosphorylated, depending on the presence of agonists, by a protein kinase partially purified from porcine brain, which had similar properties to the beta-adrenergic receptor kinase. GTP-binding regulatory proteins (Go) had dual effects on the phosphorylation of muscarinic receptors, i.e. stimulation at lower concentrations and inhibition at higher concentrations. The stimulatory effect was reproduced with the beta gamma subunit of Go and the inhibitory effect with the combination of the alpha and beta gamma subunits.

Molecular analysis of structural protein genes of the Yamagata-1 strain of defective subacute sclerosing panencephalitis virus. IV. Nucleotide sequence of the fusion gene

The full-length cDNA corresponding to the mRNA of the fusion (F) protein of the Yamagata-1 strain of subacute sclerosing panencephalitis (SSPE) virus was cloned, and its complete nucleotide sequence was determined. The F gene was composed of 2369 nucleotides and contained a single large coding region, which is located between two noncoding regions. The 5'-terminal noncoding region consisted of 584 nucleotides comprising 44.9% cytosine, and had several inverted repetitious sequences. The 3'-terminal noncoding region had a relatively low homology of 91.7% with the MV. The coding region was expanded for nucleotides 585-2189, which encoded 534 amino acids with a molecular weight of 57,963. The homology of the amino acid sequence of the F protein between the MV and SSPE virus was 96.27%, and the positions of cysteine and proline were almost identical in the two viruses. The functional domains of SSPE-virus F protein closely resembled those of MV F protein, including the cleavage site, a signal sequence, the fusion-related stretch, the transmembrane region, and four potential glycosylation sites. Four antigenic epitopes on the MV F protein were also conserved on the SSPE-virus F protein. However, deletion of one nucleotide (position 2155) of the SSPE virus was found when compared with the MV, and shifted the coding frame, causing the substitutions of 27 C-terminal amino acids of the MV F protein with 11 different residues. The variations of the C-terminal region of the F protein were observed with two other SSPE viruses, suggesting that this may be a common property of SSPE virus that differs from MV.

Molecular analysis of structural protein genes of the Yamagata-1 strain of defective subacute sclerosing panencephalitis virus. III. Nucleotide sequence of the hemagglutinin gene

The full-length cDNA corresponding to the mRNA for the hemagglutinin (H) protein of the Yamagata-1 strain of the subacute sclerosing panencephalitis (SSPE) virus was cloned and the nucleotide sequence was determined. The mRNA corresponding to the H protein was composed of 1952 nucleotides and contained a single large open reading frame, which encoded 620 amino acids with a predicted molecular weight of 69,723. This cDNA clone expressed the H protein in Cos 7 cells, and the transfected cells showed hemadsorption. The nucleotide and amino-acid sequence homology with the Edmonston strain of MV were 98.0% and 96.6%, respectively. The deduced amino acid sequence had a single hydrophobic domain near the N-terminus that was long enough to serve as an anchor in the membrane. Five potential glycosylation sites were found on the H protein at identical positions as in the H protein of MV. Cysteine and proline were located at almost identical positions as those of the H protein of MV. In addition, monoclonal antibody study revealed that three epitopes, including the domains that were involved in the biological activities of the H protein of MV, were conserved on the Yamagata-1 strain. These results suggested that the H protein of the Yamagata-1 strain of defective SSPE virus is structurally and functionally similar to that of the Edmonston strain of MV.

Molecular analysis of structural protein genes of the Yamagata-1 strain of defective subacute sclerosing panencephalitis virus. II. Nucleotide sequence of a cDNA corresponding to the P plus M dicistronic mRNA

The nucleotide sequence of a cloned cDNA corresponding to the P + M dicistronic mRNA of a subacute sclerosing panencephalitis (SSPE) virus was determined and compared with data of measles virus (MV). The dicistronic mRNA of the SSPE virus consisted of the 3' proximal 626 nucleotides of P mRNA, intercistronic trinucleotides, a full length of M mRNA, and 75 poly A nucleotides. The part encoding the P protein had a high homology to MV, except at the noncoding region. The terminating consensus sequence of the P gene and the intercistronic trinucleotides of the SSPE virus were CTAC(A)6 and CCT; in MV they are TTAT(A)6 and CTT, respectively. In the M gene, the starting consensus sequence was exactly the same as MV, but at the 5' proximal end, one third of this gene was different: The first ATG codon of the MV M gene signaling opening of the reading frame was changed to ACG in the SSPE virus and one long open reading frame started from the third ATG codon. The stop codon (TAG) of the MV M gene was also changed to CAG in the SSPE virus. Thus, the deduced SSPE-virus M protein lacked 50 amino acids at the amino terminal and had 15 extra amino acids at the carboxyl end when compared with the MV M protein.

[Effects of immunoglobulin preparations on the opsonic activities against various pathogens]

We evaluated the opsonic activities of human intravenous immunoglobulin (IVIG) preparations against pathogenic organisms by measuring the luminol-enhanced chemiluminescence (CL) from human polymorphonuclear leukocytes (PMN) during the phagocytosis of these organisms. Polyethylenglycol-treated IVIG significantly increased the CL of PMN by opsonization against various bacteria and Candida albicans (p less than 0.01). The high CL induced by IVIG with intact Fc-fragment showed no significant differences among lots or preparations made by different treatments. In both PMN-CL in the absence of human serum and whole blood CL at low concentration of serum complement, the CL response was not affected by pepsin-treated IVIG. In the severely burned patients' blood with a very low concentration of serum immunoglobulin, IVIG with intact Fc-fragment significantly increased CL (p less than 0.01). It is suggested that administration of IVIG is useful against infections in these patients. The measurement of whole blood CL in vitro may be useful for evaluating the opsonic activity of IVIG against target pathogens in vivo.

Diversity of matrix protein in subacute sclerosing panencephalitis and measles virus-infected cells

Expression of the viral matrix (M) proteins in Vero cells infected with 18 strains of subacute sclerosing panencephalitis (SSPE) virus and measles virus was examined by immunocytochemistry and Western blot analysis using an anti-M monospecific serum and two sera against the M protein specific synthetic peptides. By immunocytochemistry using the anti-M monospecific serum, M protein was detected in all of the virus-infected cells regardless of cell-free virus production. M proteins of the seven non-productive strains were found to vary significantly in their epitope, in their reactivity to different assay systems, and in their molecular weight, whereas M proteins of the other 11 productive strains were detected consistently. These results suggest diversification of M protein of the non-productive strains.

Location in muscarinic acetylcholine receptors of sites for [3H]propylbenzilylcholine mustard binding and for phosphorylation with protein kinase C

Muscarinic acetylcholine receptors purified from porcine cerebra or atria were covalently labeled with [3H]propylbenzilylcholine mustard ([3H]PrBCM), and then the labeled receptors were subjected to limited hydrolysis with trypsin, V8 protease, and lysyl endopeptidase, followed by analysis involving sodium dodecyl sulfate-polyacrylamide gel electrophoresis, fluorography, autoradiography, or immunostaining. The labeled peptides were located on the basis of their reactivity with antibodies raised against three synthetic peptides with partial sequences of the m1 or m2 receptor, and of their sensitivity to endoglycosidase F, which was taken as evidence that they contain glycosylation sites near the N terminus. The [3H]PrBCM-binding site in both cerebral and atrial receptors was found to be located between the N terminus and the second intracellular loop, because the size of the smallest deglycosylated peptide that contained both the [3H]PrBCM-binding and glycosylation sites was approximately 16 kDa. Cerebral receptors were 32P-phosphorylated with protein kinase C, and the major phosphorylation sites in cerebral muscarinic receptors were found to be located in a C-terminal segment including a part of the third intracellular loop, because a 32P-labeled peptide of 12-14 kDa reacted with anti-(m1 C-terminal peptide) antiserum. The presence of an intramolecular disulfide bond, probably between Cys 98 and Cys 178 in the first and second extracellular loops, respectively, was suggested by the finding that a peptide of approximately 17 kDa containing the [3H]PrBCM-binding site, but not the glycosylation sites, was partly converted to a peptide of approximately 12 kDa on treatment with beta-mercaptoethanol.

Phosphorylation by protein kinase C of the muscarinic acetylcholine receptor

Muscarinic acetylcholine receptors purified from porcine cerebrum were phosphorylated by protein kinase C purified from the same tissue. More than 1 mol of phosphate was incorporated per mole of receptor, with both serine and threonine residues being phosphorylated. Neither the degree nor the rate of the phosphorylation was affected by the presence or absence of acetylcholine. GTP-sensitive high-affinity binding with acetylcholine was observed for muscarinic receptors reconstituted with GTP-binding proteins (Gi or Go), irrespective of whether muscarinic receptors or the GTP-binding proteins had been phosphorylated by protein kinase C or not. This indicates that the interaction between purified muscarinic receptors and purified GTP-binding proteins in vitro is not affected by their phosphorylation.

Carbachol-induced potentiation and inhibition of acid secretion by guinea pig gastric gland

The effects of muscarinic ligands on acid secretion were examined by estimating the accumulation of [14C]aminopyrine in gastric glands isolated from guinea pigs. The accumulation of [14C]aminopyrine in the presence of 0.1 mM histamine was potentiated by 1 microM carbachol but suppressed by 1 mM. These two effects of carbachol were abolished by atropine, pirenzepine and AF-DX 116. Assuming that the binding of carbachol to one site (Site 1) increases [14C]aminopyrine accumulation but its binding to the other site (Site 2) reduces [14C]aminopyrine accumulation, we analysed the dose-response curves for the carbachol effects in the absence and presence of different concentrations of atropine, pirenzepine and AF-DX 116. The dissociation constants determined for these ligands at Sites 1 and 2 were as follows: carbachol, 0.28 and 7.1 microM; atropine, 0.28 and 0.54 nM; pirenzepine, 45 and 560 nM; and AF-DX 116, 380 and 4400 nM, respectively. The binding of [3H]N-methylscopolamine to the gastric glands indicated the presence of two populations of binding sites with different affinities for the above ligands, other than atropine. The apparent dissociation constants, which were estimated by analysing the displacement curves for [3H]N-methylscopolamine binding, were as follows: carbachol, 0.18 microM (10%) and 31 microM (90%); atropine, 1.24 nM; pirenzepine, 15 nM (16%) and 220 nM (84%); and AF-DX 116, 370 nM (10%) and 2970 nM (90%). These results suggest that there are two kinds of muscarinic acetylcholine receptors in the guinea pig gastric gland, one potentiating and the other inhibiting the acid secretion induced by histamine.

[The present aspect of tuberculous pleurisy--report of the 29th series (A) of CSUCT--Cooperative Study Unit of Chemotherapy of Tuberculosis (CSUCT) of the National Sanatoria in Japan]

CSUCT carried out 9-21 month's follow up of 273 patients with exudative tuberculous pleurisy who were admitted to 39 national sanatoria in 1985, and were treated for the first time. The background factors of the patients at the time of admission were as follows: the average age, 47.2; male/female ratio 3:1; idiopathic pleurisy 163 cases and secondary pleurisy 110 cases. Distribution of maximal temperature on admission; 37.0 degrees C or less 24.4%; 37.1-38.0 degrees C 37.8%; 38.1-39.0 degrees C 28.5%; higher than 39.0 degrees C 9.3%. Younger patients tended to show higher temperature than the older. The positivity of tuberculin reaction was 84.3%, and among them 34% were strongly positive (greater than or equal to 20 mm). There was no correlation between the volume of pleural effusion and the intensity of tuberculin reaction. In patients more than 60 years of ages, the positivity was low (76.0%). The erythrocyte sedimentation rate (after 1 hour) was 63.6 +/- 31.6 mm.

CLINICAL SYMPTOMS

cough in 72%; sputum in 48.5%; chest pain in 57.5%; tubercle bacilli in sputum in 11.6%. We compared idiopathic pleurisy (I) and secondary pleurisy (S) and total cases of pleurisy (T) regarding several factors; average age (I: 46.7, S: 48.0, T: 47.2); peak season of incidence (I: Feb. Mar. S: Mar. April, T: Feb. Mar. April); the period of hospitalisation (I: 4.07 months, S: 5.80 months, T: 4.77 months); the positive rate of tubercle bacilli in the pleural effusion (I: 9.0%, S: 12.9%, T: 10.5%); %VC (mean value) on admission (I: 71.4%, S: 69.8%, T: 70.7 +/- 17.0%); %VC after treatment (I: 79.0%, S: 79.7%, T: 79.4 +/- 17.9%), and we found no significant difference in the above factors between I. and S. In 49 patients who were treated by chemotherapy with steroids, %VC before treatment was 68.9% (mean value), and that after treatment was 81.2% (mean value), however, there was no significant difference between the %VC of these patients and that of total patients. Recent chemotherapy (SM or EB + INH + RFP) greatly contributed to improve clinical symptoms by accelerating the absorption of pleural effusion and in minimizing the formation of pleural thickening. Previously, we experienced often deterioration of tuberculous lesions in relation to the use of steroids. By the use of recent intensified chemotherapy, the harmful side effects of steroids became almost insignificant, and at the same time, treatment with steroids is needed only in a few cases.