[The role of endotoxin in the bronchial hyperreactivity formation]

Endotoxin was as a pathogen to investigate its effects on bronchial hyperreactivity formation. The latent periods of guinea pigs inhaled histamine and PD2 value of isoproterenol were markedly decreased 4 days after the intraperitoneal injection of endotoxin 1 mg/kg, meanwhile PD2 value of histamine and histamine levels of lung tissue and plasma were increased significantly. These results indicate that endotoxin is a very important factor in the infection induced bronchial hyperreactivity.

EDAP piezoelectric shock wave lithotripsy for gallbladder stones

EDAP piezoelectric shock wave lithotripsy combined with oral ursodeoxycolic acid dissolution of stones was used to treat 1055 patients with gallbladder stones. 926 of them (87.8%) were followed up for more than 1 year. The patients were divided into two groups: Group I, 637 patients with functioning gallbladders containing one radiolucent stone less than or equal to 20 mm in diameter or 2 to 3 stones each less than or equal to 12 mm, and Group II: 289 patients with stones exceeding the above criteria. The stone fragmentation rate was 96.2% and 94.1% respectively in Group I and in Group II. Gallbladder stones disappeared in 18.5%, 35.0%, 46.2% and 52.4% of the patients in Group I in 1, 3, 6, and 12 months after treatment and 7.3%, 11.4%, 20.1%, and 27.7% in Group II. The treatment was more effective for solitary stones less than or equal to 20 mm in diameter. No serious complications were noted. The midterm curative effect was satisfactory. Further study is required to raise the curative effect and prevent stone recurrence.

Reconstituted human granulocyte-macrophage colony-stimulating factor receptor transduces growth-promoting signals in mouse NIH 3T3 cells: comparison with signalling in BA/F3 pro-B cells

Granulocyte-macrophage colony-stimulating factor (GM-CSF) plays a critical role in growth and differentiation of myeloid cells. We previously reconstituted high-affinity human GM-CSF receptor (hGM-CSFR) in a pro-B cell line, BA/F3, by cotransfecting alpha- and beta-chain cDNA clones and showed that the reconstituted receptor could transduce growth-promoting signals. The high-affinity hGM-CSFR was also reconstituted in mouse NIH 3T3 cells, but its ability to transduce signals in fibroblasts remained undetermined. In the present study, we further characterized signal transduction by the reconstituted hGM-CSFR in both NIH 3T3 cells and BA/F3 cells. We found that the reconstituted hGM-CSFR transduces signals in NIH 3T3 fibroblasts and BA/F3 cells in response to hGM-CSF to activate transcription of the c-fos, c-jun, and c-myc proto-oncogenes. hGM-CSF also induces protein tyrosine phosphorylation and DNA synthesis in both cell types. These results indicated that hGM-CSFR is functional in fibroblasts, that signal transduction via hGM-CSFR in fibroblasts involves tyrosine kinase(s), and that association of hGM-CSFR with a factor(s) specific to hematopoietic cell lineage is not essential to transduce growth-promoting signals.

Transferrin subtypes in 11 south China minority populations

Transferrin subtypes were determined by isoelectric focussing (IEF) in a total of 2,121 individuals from 11 South China minority populations. The C1, C2 and DCHI alleles were present in all the populations; B alleles were lacking, C4 was found in 3 populations and C3 in 6. C2 and C4 allele frequencies are notable in these minority groups. The frequency of the C2 allele was higher (0.25-0.38) than that of Han Chinese (0.18-0.25). In Bai the C2 frequency was as high as 0.38. The C4 allele was present at a low frequency (less than 0.01), which suggests that this allele probably existed in the ancestral Mongoloid population at a low frequency and increased in frequency in Amerindians due to genetic drift or other factors.

Isolation and characterization of a functional cDNA encoding ICP0 from herpes simplex virus type 1

The IE-0 gene of herpes simplex virus type 1 (HSV-1) contains two introns and encodes ICP0, a powerful transcriptional activator. We have isolated a cDNA clone that encodes ICP0 from a lambda gt10 cDNA library constructed from RNAs made from HSV-1-infected HeLa cells. DNA sequence analysis of this clone confirmed the predicted intron/exon boundaries (L. J. Perry, F. J. Rixon, R. D. Everett, M. C. Frame, and D. J. McGeoch, J. Gen. Virol. 67:2365-2380, 1986). Following transfection, a plasmid containing the cDNA copy of IE-0 directed the synthesis of ICP0, which was appropriately compartmentalized and distributed in the nucleus, as revealed by immunofluorescence. A transient expression assay was used to demonstrate that this cDNA copy retained the ability to transactivate the HSV-1 promoters for the IE-0 gene (an immediate-early gene), the thymidine kinase gene (an early gene), and the glycoprotein C gene (a late gene). The product of this cDNA clone cooperated with ICP4 to activate expression from the thymidine kinase gene promoter in a synergistic manner. The availability of a functional cDNA copy encoding ICP0 provides the opportunity to express this protein in vector systems that do not recognize eucaryotic donor and acceptor splicing signals to overexpress ICP0.

Mutational analysis of the sequence encoding ICP0 from herpes simplex virus type 1

In-frame codon insertion and deletion mutants were constructed in a plasmid containing the sequence that encodes ICP0, a transcriptional activator of herpes simplex virus type 1 (HSV-1). The effect of these mutations was analyzed in a transient expression assay using the promoters for, the IE-0 gene (an immediate early (alpha) gene), the thymidine kinase gene (an early (beta) gene), and the glycoprotein C gene (a late (gamma) gene) fused to reporter cassettes that encoded either beta-galactosidase or chloramphenicol acetyl transferase. Assays were performed in the presence or absence of a plasmid encoding ICP4, the major regulatory protein of HSV-1. Our results demonstrate that ICP0-mediated transactivation varied depending on the position of the insertion in the gene. One region of this protein was consistently shown to be required for full activation of each promoter examined either in the presence or in the absence of ICP4. This region overlaps with a cysteine-rich region and coincides with a transactivator domain identified in another extensive mutational analysis of this sequence. Analysis of the deletion mutants generated in this study demonstrated that the carboxy-terminal regions were required for activation in certain circumstances and that this varied depending on the promoter being assayed and the cell type in which the analysis was performed.

Preparative slab electrofocusing of methane monooxygenase from a type I methanotroph Methylomonas GYJ3

The isolation and purification of methane monooxygenase from a type I methanotroph Methylomonas GYJ3 to near homogeneity is reported. The isoelectric focusing in flat-bed granulated gels has resolved the methane monooxygenase into three protein components. The specific activity of the enzyme is 198.4 n mol per min per mg protein, degree of purification 4.13-fold. Recovery of the focused proteins is high and elution simple. Several purification steps may be omitted from the previously published scheme by other techniques.

The CDC4 gene product is associated with the yeast nuclear skeleton

The CDC4 gene product of Saccharomyces cerevisiae is required at the late G1/S phase boundary of the cell cycle. In an attempt to better understand the function of CDC4, we performed experiments to localize this protein in the yeast cell. Using antisera, directed against a TrpE-CDC4 fusion protein, to analyze immuno-blots of different subcellular fractions from yeast, we demonstrated that the CDC4 gene product localizes in the nucleus by two different biochemical preparations of the yeast nucleoskeletal proteins. Immunofluorescence microscopy further confirmed its nuclear localization. These data support a model that includes the CDC4 gene product as a component of the yeast nuclear skeleton. The significance of this association in relationship to the biological role of CDC4 is discussed.

Reactivation of latent herpes simplex virus by adenovirus recombinants encoding mutant IE-0 gene products

We have previously shown that adenovirus recombinants expressing functional ICP0 reactivate latent herpes simplex virus type 2 (HSV-2) in an in vitro latency system. This study demonstrated that ICP0, independent of other HSV gene products, is sufficient to reactivate latent HSV-2 in this in vitro system. To assess the effects of defined mutations in the sequence encoding ICP0 (IE-0) on reactivation, seven in-frame insertion and three in-frame deletion mutants were moved into an adenovirus expression vector. Each recombinant directed the synthesis of stable ICP0 of the correct size. The transactivation activity of the mutated sequences in these recombinants was similar to that when they were tested in plasmids. When these recombinants were examined for their ability to reactivate in the in vitro latency system, mutants with dramatic defects in transactivation (Ad-0/125, Ad-0/89, Ad-0/2/7, and Ad-0/88/93) were unable to reactivate latent HSV-2 independent of the multiplicity of infection. An exception to this correlation was the finding that Ad-0/89, which transactivated poorly, was able to reactivate latent virus after prolonged incubation whereas other transactivation-deficient mutants could not. Moreover, the presence of ICP4 did not compensate for the inability of any of the recombinants tested to reactivate HSV-2. These results show that (i) the transactivation domains of ICP0 are also used in reactivation, (ii) the presence of another essential HSV regulatory protein ICP4 does not alter the pattern of reactivation by ICP0, and (iii) mutations in some regions of IE-0 previously shown to affect viral growth and plaque formation did not alter its ability to reactivate in this in vitro system.

Extracorporeal shock wave lithotripsy. Experience in treating 245 patients with gallbladder stones

An EDAP LT-01 lithotripter was used to treat 245 patients with functioning gallbladders containing one to three radiolucent stones of less than 20 mm in diameter. Ursodeoxycholic acid was administrated as adjuvant litholytic therapy. The gallbladder stones disintegrated in 98.8% of patients and disappeared completely in 21.2% within 1 month after lithotripsy, in 26.5% within 2 months, in 33.9, 40, 46.5, 48.6 and 53.9% within 3, 4, 6, 9, and 12 months, respectively. Adverse effects after lithotripsy were dull abdominal pain (49.4%), biliary colic (13.1%), jaundice (1.2%), and pancreatitis (0.4%). Extracorporeal shock wave lithotripsy combined with litholytic therapy is a non-invasive, painless, safe, and effective treatment in selected patients. Patients with solitary radiolucent stone less than 20 mm in diameter are considered candidates for extracorporeal shock wave lithotripsy (ESWL). The key to success of ESWL lies in the strict selection of patients, careful monitoring throughout the lithotriptic procedure, and enough litholytic therapy. The disadvantages of this method include strict selection of patients and high costs, poor curative effect, and recurrence of stones (11.4% of patients).

[Protective effects of Panax notoginseng saponins on experimental myocardial injury induced by ischemia and reperfusion in rat]

Effects of total saponins of Panax notoginseng (PNS) and purified ginsenosides Rb1 and Rg1 from PNS on myocardial injury induced by cardiac ischemia and reperfusion were studied with rat hearts in situ and in vitro. In pentobarbital-anesthetized rats, PNS pretreatment (100 and 200 mg/kg) provided significant reduction in myocardial infarct size after left descending coronary artery ligation (40 min) and reperfusion (120 min) in comparison with the control. PNS 12.5 and 25 mg/L, Rb1 10 mg/L, and Rg1 10 mg/L significantly decreased cardiac CPK release, attenuated myocardial Ca2+ accumulation, reduced malondialdehyde (MDA) production and prevented reduction of superoxide dismutase (SOD) activity in comparison with the control in perfused isolated rat hearts with global ischemia (40 min) and reperfusion (15 min). The results show that PNS, Rb1, and Rg1 prevent cardiac ischemia and the action is considered to be related to the inhibition of lipid peroxidation.

[Effects of Panax notoginseng saponins on cardiac action potentials and slow inward current]

The effects of total saponins of Panax notoginseng (PNS) on contraction force, normal and slow response action potentials and slow inward current of guinea pig papillary muscles were studied by intracellular microelectrodes and voltage clamp techniques. The contraction force was decreased and the APD20, APD90 of normal AP were shortened in the presence of PNS 1 mg/ml, while the RP, APA and Vmax remained unchanged. The APA of slow AP induced with high K+ was decreased to 85% of its normal value after 20 min of perfusion with PNS solution. Isi was decreased from a peak value of 9.8 +/- 2.0 to effects of PNS on slow affecting INa. The 6.9 +/- 3.6 microA without AP and Isi were reversed by increasing calcium concentration. The results indicate that PNS has a selective blocking effect on calcium channels.

Isolation and characterization of auxotrophic mutants of Legionella pneumophila that fail to multiply in human monocytes

Attempts to isolate auxotrophic mutants of Legionella pneumophila have been hampered by the complex nutritional composition of the media used to cultivate this organism. We developed a semidefined medium, designated CAA, to facilitate the isolation and characterization of Legionella auxotrophs. Unlike previously described chemically defined media for this organism, L. pneumophila formed colonies on CAA agar. Using this medium, we isolated several independent tryptophan auxotrophs of strain Philadelphia-1 after ethyl methanesulfonate mutagenesis and penicillin enrichment. Trimethoprim selection was used to isolate several independent thymidine-requiring mutants of the same strain. The thymidine auxotrophs exhibited a marked decrease in viability when they were deprived of thymidine. The results of monocyte infection experiments with both the tryptophan and thymidine auxotrophs indicated that the thymidine auxotrophs were incapable of intracellular survival or multiplication. In contrast, the tryptophan auxotrophs grew well in monocyte cultures. The isolation of additional auxotrophic mutants will facilitate the study of the nutritional requirements of L. pneumophila for growth in human mononuclear phagocytes.

Studies on antihepatitic drugs. Total synthesis of (+/-)schizandrin C and its analogs

This paper reports the total synthesis of (+/-) schizandrin, C, namely 5,6,7,8-tetrahydro-1, 12-dimethoxy-2, 3, 10, 11-bismethylenedioxy-6, 7-cis-dimethyldibenzo (a, c) cyclooctene (12B), a new active SGPT lowering principle isolated from the Chinese medical plant Schizandra chinensis, and its 6, 7-trans-dimethyl isomer (16B). We also synthesized two more isomers, namely 5, 6, 7, 8-tetrahydro-3, 10-dimethoxy-1, 2, 11, 12-bismethylenedioxy-6, and 7-cis-(and trans-) dimethyldibenzo (a, c) cyclooctene (12A and 16A). The NMR, UV and mass spectra of these four isomers are discussed. IR (in chloroform), UV, NMR and MS of synthetic schizandrin C (12B) are identical with those of the natural compound.