Selection of murine lymphoid and hematopoietic cells using polystyrene tissue culture devices containing covalently immobilized antibody

We have established rapid procedures that negatively deplete and positively select for specific murine cell populations. By using polystyrene tissue culture flasks containing a covalently bound mouse anti-rat antibody and specific anti-mouse, cell-surface antigen antibodies, we easily and efficiently depleted greater than 90% of the mature lineage cells from murine bone marrow. This selection procedure resulted in an enrichment of progenitor colonies (CFU-Cs) in murine bone marrow. Using the same polystyrene tissue culture devices, we can directly isolate CD117+ (c-kit+) murine hematopoietic cells. As few as 2000 of these CD117+ cells rescued and reconstituted lethally irradiated recipients in a murine bone marrow transplant model.

[Chemical constituents in roots of Ampelopsis sinica (Miq.) W.T. Wang]

Six compounds were isolated from the roots of Ampelopsis sinica and identified as lupeol, beta-sitosterol, daucosterol, catechin, sucrose and palmitic acid on the basis of spectroscopic. Lupeol is found in Ampelopsis genus for the rirst time.

Systematic screening for mutations in the human serotonin-2A (5-HT2A) receptor gene: identification of two naturally occurring receptor variants and association analysis in schizophrenia

A statistically significant association between a silent mutation (102T/C) in the serotonin-2A (5-HT2A) receptor gene and schizophrenia has recently been reported in a sample of Japanese patients and healthy controls. This finding suggests that genetic predisposition to schizophrenia may be affected by a functional 5-HT2A receptor variant that is in linkage disequilibrium with 102T/C. In the present study, we have sought to identify genetic variation in the 5-HT2A receptor gene by screening genomic DNA samples from 91 unrelated subjects comprising 45 patients with schizophrenia and 46 healthy controls by using single-strand conformation analysis. We have identified four nucleotide sequence variants. Two sequence changes would result in protein alterations: a substitution of threonine by asparagine at position 25 (Thr25Asn), and a substitution of histidine by tyrosine at position 452 (His452Tyr). In order to test for a possible contribution to the development of schizophrenia, we have determined allele frequencies in extended samples of unrelated patients and healthy controls. The two amino acid substitutions are found with similar frequencies in patients and controls, indicating that the presence of these variants is not causally related to the development of schizophrenia. However, the reported association of the non-coding polymorphism 102T/C with the disease has also been detected in our sample (P=0.041, odds ratio=1.28, 95% confidence interval 1.012-1.623).

Intact 5-HT2A receptor exons and the adjoining intron regions in schizophrenia

Genes that regulate serotonergic (5-HT) systems may underlie the etiology of schizophrenia. In this study the gene encoding the 5-HT2A receptor in schizophrenics and healthy controls was examined. First, we sequenced all exons and the flanking introns of the 5-HT2A receptor gene in 10 schizophrenics and 10 controls. The substitution of C for T at position 102 in exon, which had been reported by Warren et al. (1993), was confirmed. Restriction fragment length polymorphism (RFLP) analysis revealed no association between polymorphism and schizophrenia. There was no association between the polymorphism and subdiagnosis, family history, age of onset, amounts of antipsychotics, or positive and negative symptoms before or after medication. Other polymorphisms in the gene were screened in 100 schizophrenics by the single-strand conformation polymorphism method, but none was found. Our results suggest that an abnormality in the 5-HT2A receptor gene in schizophrenia is unlikely.

Ibogaine block of the NMDA receptor: in vitro and in vivo studies

Ibogaine is an hallucinogenic indole alkaloid claimed to have anti-addictive properties. Although its mechanism of action is unknown, binding studies have indicated that the drug may interact with N-methyl-D-aspartate (NMDA) receptors. We further investigated the nature of the interaction between ibogaine and NMDA receptors in voltage clamp and binding studies, and sought to confirm that the drug has NMDA receptor blocking activity in vivo. In whole-cell recordings from cultured rat hippocampal neurons, ibogaine caused a slow, concentration-dependent block of NMDA-induced currents (IC50, 3.1 microM at -60 mV). In contrast, ibogaine failed to affect either kainate- or gamma-aminobutyric acid-evoked currents. The blockade of NMDA currents was use- and voltage-dependent, and the long lasting ibogaine block could be occluded by co-application of Mg2+. Ibogaine also inhibited equilibrium [3H]dizocilpine binding to NMDA receptors in rat forebrain membranes (IC50, 3.2 microM). We conclude that ibogaine is an open channel NMDA receptor antagonist. Administration of ibogaine to mice resulted in complete protection in the maximal electroshock test (ED50, 31 mg/kg, i.p.) and partial protection against NMDA-induced lethality, confirming that ibogaine can block NMDA receptors in vivo.

Preclinical evidence of Alzheimer's disease in persons homozygous for the epsilon 4 allele for apolipoprotein E

BACKGROUND

Variants of the apolipoprotein E allele appear to account for most cases of late-onset Alzheimer's disease, and persons with two copies of the epsilon 4 allele appear to have an especially high risk of dementia. Positron-emission tomography (PET) has identified specific regions of the brain in which the rate of glucose metabolism declines progressively in patients with probable Alzheimer's disease. We used PET to investigate whether these same regions of the brain are affected in subjects homozygous for the epsilon 4 allele before the onset of cognitive impairment.

METHODS

Apolipoprotein E genotypes were established in 235 volunteers 50 to 65 years of age who reported a family history of probable Alzheimer's disease. Neurologic and psychiatric evaluations, a battery of neuropsychological tests, magnetic resonance imaging, and PET were performed in 11 epsilon 4 homozygotes and 22 controls without the epsilon 4 allele who were matched for sex, age, and level of education. An automated method was used to generate an aggregate surface-projection map that compared regional rates of glucose metabolism in the two groups.

RESULTS

The epsilon 4 homozygotes were cognitively normal. They had significantly reduced rates of glucose metabolism in the same posterior cingulate, parietal, temporal, and prefrontal regions as in previously studied patients with probable Alzheimer's disease. They also had reduced rates of glucose metabolism in additional prefrontal regions, which may be preferentially affected during normal aging.

CONCLUSIONS

In late middle age, cognitively normal subjects who are homozygous for the epsilon 4 allele for apolipoprotein E have reduced glucose metabolism in the same regions of the brain as in patients with probable Alzheimer's disease. These findings provide preclinical evidence that the presence of the epsilon 4 allele is a risk factor for Alzheimer's disease. PET may offer a relatively rapid way of testing future treatments to prevent Alzheimer's disease.

Mouse Sin3A interacts with and can functionally substitute for the amino-terminal repression of the Myc antagonist Mxi1

Mxi1 is a basic region helix-loop-helix leucine zipper (bHLH/LZ) protein that, in association with Max, antagonizes Myc oncogenic activities. A possible mechanistic basis for Mxi1-mediated repression was provided by the recent demonstration that the repressive potential of Mxi1 correlates with its ability to physically associate with mSin3B, one of two mammalian homologues of the yeast transcriptional repressor SIN3. Here, we sought to characterize more fully the physical properties of the second homologue, mSin3A and to determine whether the recruitment of mSin3A by Mxi1 is indeed required for anti-Myc activity. Transient transfection of mammalian cells showed that the mSin3A protein can associate with the strong repressive isoform of Mxi1 (Mxi1-SR) and that, like other Myc superfamily members, both mSin3A and Mxi1-SR localize to the nucleus. From a developmental standpoint, a comparative analysis of Myc, Mxi1-SR and Sin3A expression during postnatal mouse development and in differentiating mouse erythroleukemia (MEL) cells revealed that dramatic and reciprocal changes in Myc and Mxi1-SR mRNA levels are accompanied by minimal stage-specific changes in mSin3A gene expression. This constant expression profile, coupled with the observation that over-expression of mSin3A does not augment the anti-Myc activity of Mxi1-SR in the rat embryo fibroblast (REF) transformation assay, suggests that mSin3A is not a limiting factor in the regulation of Myc superfamily function. Finally, a mSin3A-Mxi1 fusion protein, in which the amino terminal mSin3-interacting domain of Mxi1-SR was replaced with the full-length mSin3A, exhibited a level of repression activity equivalent to, or greater than, the level of repression obtained with Mxi1-SR. Taken together, these observations directly demonstrate that the amino-terminal repression domain of Mxi1-SR functions solely to recruit mSin3A and possibly other proteins like mSin3A and this association is necessary for the anti-Myc activity of Mxi1-SR.

Chemical kinetic theory: understanding cell-cycle regulation

Progress of a cell through its reproductive cycle of DNA synthesis and division is governed by a complex network of biochemical reactions controlling the activities of both M-phase- and S-phase-promoting factors. Standard chemical kinetic theory provides a disciplined method for expressing the molecular biologists' diagrams and intuition in precise mathematical form, so that qualitative and quantitative implications of our 'working models' can be derived and compared with experiment.

Alanyl-glutamine dipeptide-supplemented parenteral nutrition improves intestinal metabolism and prevents increased permeability in rats

OBJECTIVE

The authors determined the effects of alanyl-glutamine-supplemented total parenteral nutrition (TPN) on mucosal metabolism, integrity, and permeability of the small intestine in rats.

METHODS

Male Sprague-Dawley rats were randomized to receive TPN supplemented with a conventional amino acids mixture (STD group) or the same solution supplemented with alanyl-glutamine; both solutions were isocaloric and isonitrogenous. On the seventh day of TPN, D-xylose and fluorescein isothiocyanate (FITC)-dextran were administered orally. One hour later, superior mesenteric vein (SMV) D-xylose and plasma FITC-dextran concentration were measured. Intestinal blood flow and calculated intestinal substrates flux were measured with ultrasonic transit time flowmetery.

RESULTS

Plasma FITC-dextran increased significantly in the STD group. Intestinal blood flow and SMV D-xylose concentration did not differ between the groups. Mucosa weight, villus height, mucosal wall thickness, mucosal protein, and DNA and RNA content in jejunal mucosa were significantly increased in the alanyl-glutamine group. Jejunal mucosal glutaminase activity and net intestinal uptake of glutamine (glutamine flux) were significantly higher in the alanyl-glutamine group as compared with the STD group.

CONCLUSION

Addition of alanyl-glutamine dipeptide to the TPN solution improves intestinal glutamine metabolism and prevents mucosal atrophy and deterioration of permeability.

Adhesive mucous gel layer and mucus release as intestinal barrier in rats

BACKGROUND

Although it has been reported that total parenteral nutrition induces an increased intestinal permeability and a decreased mucous gel layer covering the intestinal epithelium, the role of mucous gel on intestinal permeability has not been well understood. We examined the in vivo effects of N-acetyl cysteine (NAC) as mucolytic agent and colchicine as suppressant of the mucus production on the intestinal transmission of fluorescein isothiocyanate dextran 70,000 (FITC-dextran).

METHODS

Rats were divided into four groups. In each group, FITC-dextran (750 mg/kg) with or without NAC (3000 mg/kg) was injected into the small intestinal lumen 3 hours after intraperitoneal injection of saline or colchicine (Col, 10 mg/kg). Thirty minutes after injection of FITC-dextran, blood samples were taken from portal vein to analyze plasma fluorescein concentration by fluorescence spectrometry. Samples of small intestine were sectioned in a cryostat for fluorescence microscopy, and the identical sections were stained by periodic acid-Schiff reaction.

RESULTS

Plasma FITC-dextran level in NAC group was higher than that in control group (p < .01), that in Col + NAC group was higher than that in Col group (p < .01) and that in Col + NAC group was higher than that in NAC group (p < .05). The spaces between villi were filled with mucous gel in the control and Col groups, whereas those were not entirely filled with mucous gel in NAC and Col + NAC groups. FITC-dextran and mucous gel showed complementary distribution in all rats. The villous interstitial edema was recognized in NAC group and the villi were disrupted in Col + NAC group.

CONCLUSIONS

These results suggest that intestinal permeability is possibly affected not only by the mucous gel covering the intestinal epithelium but also by mucus release from goblet cells of the small intestine.

Speaker identification using time-delay HMEs

In this paper, we extend the Hierarchical Mixture of Experts (HME) to temporal processing and explore it for a substantial problem, that of text-dependent speaker identification. For a specific multiway classification, we propose a generalized Bernoulli density instead of the multinomial logit density to avoid the instability during training. Time-delay technique is applied for spatio-temporal processing in the HME and a combining scheme is presented for combining multiple time-delay HMEs in order to complete a multi-scale analysis for the temporal data. Using the time-delay HME along with the EM algorithm as well as the combination of multiple time-delay HMEs, the speaker identification system has a good performance and yields significantly fast training. We have also addressed some issues about the time-delay techniques in the HME.

NADPH-diaphorase in the developing rat: lower brainstem and cervical spinal cord, with special reference to the trigemino-solitary complex

A previous study indicated that in adult rat, a distinctive neuronal group in the dorsomedial division of the subnucleus oralis of the spinal trigeminal nucleus (SpVo) and the rostrolateral part of the nucleus of the solitary tract (Sn) is stained for nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d), and suggested that the labeled structures are involved with sensorimotor reflexive functions. This study aimed to characterize the developmental expression of NADPH-d in SpVo and Sn, including other areas of the lower brainstem and cervical spinal cord, by means of the enzyme histochemical staining technique, from the prenatal through the postnatal period. On embryonic day 12 (E12), no neurons in the brain were stained for NADPH-d, whereas blood vessels were stained. Labeling in the vessels was consistently present throughout pre- and postnatal periods but decreased with development. On E15, labeled neurons appeared in the dorsomedial part of SpVo and the rostrolateral part of Sn, but not in the other nuclei. The labeled neurons in both nuclei increased in numbers drastically to E17. Postnatally, they tended to increase gradually in Sn, but to decrease slightly in SpVo. The cell size of labeled neurons reached a plateau at E17 in SpVo, but at postnatal day 4 (P4) in Sn. In other nuclei on E17, labeling appeared in the lateral paragigantocellular reticular, intermediate reticular, medullary reticular, pedunculopontine tegmental, and spinal vestibular nuclei, and laminae V, VI, and X of the cervical spinal cord. On E20 and P0, labeling appeared in the dorsal column, laterodorsal tegmental, raphe obscurus, parvocellular reticular, ventral gigantocellular reticular, and parahypoglossal nuclei, and laminae IX of the cervical spinal cord. On P4 labeling appeared in the parabrachial and median raphe nuclei, medial and caudolateral Sn, the magnocellular zone of subnucleus caudalis of the spinal trigeminal nucleus (SpVc), and laminae III/IV of the cervical spinal cord. On P10, labeling appeared in the paratrigeminal and dorsal raphe nuclei, the superficial zone of SpVc, and laminae I/II of the cervical spinal cord. No newly labeled neurons appeared in any nuclei after P14. The very early appearance of NADPH-d staining in SpVo and Sn, which precedes the appearance of NADPH-d elsewhere in the brainstem, suggests that the nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) system has an important role for primitive orofacial sensorimotor reflexive functions. Furthermore, the pattern of developmental expression of NADPH-d in SpVo and Sn suggests that the NO/cGMP system is organized in a distinct manner in different nuclei.

Influence of C terminus on monoamine oxidase A and B catalytic activity

Monoamine oxidase (MAO) A and B play important roles in the metabolism of neurotransmitters and dietary amines. The domains important for enzyme specificities were studied by construction of chimeric MAOA/B enzymes. Exchange of the N-terminal 45 amino acids of MAOA with the N-terminal 36 residues of MAOB (chimeric enzymes B36A and A45B) resulted in the same substrate and inhibitor sensitivities as the wild-type MAOA or B. Thus, the N terminus may not be responsible for MAOA or B enzyme specificities. When MAOB C-terminal residues 393-520 were replaced with MAOA C-terminal residues 402-527 (chimeric B393A) catalytic activity was not detectable. Chimeric B393A consists of eight residues with different charges, three less proline residues (458, 476, and 490), and one additional proline at 518 compared with wild-type MAOB. These differences may have induced conformational changes and affected MAOB catalytic activity. Thus, the C terminus of MAOB is critical for maintaining MAOB in an active form. It is interesting that when the C terminus of MAOA was switched with MAOB (chimeric A402B), little effect was observed on MAOA catalytic activity. This new information is valuable for further studies of the structure and function relationship of this important enzyme.

Molecular neuroanatomy of human monoamine oxidases A and B revealed by quantitative enzyme radioautography and in situ hybridization histochemistry

Monoamine oxidases are key enzymes in the metabolism of amine neurotransmitters and neuromodulators and are targets for drug therapy in depression, Parkinson's and Alzheimer's diseases. Knowledge of their distribution in the brain is essential to understand their physiological role. To study the regional distribution and abundance of monoamine oxidases A and B in human brain, pituitary and superior cervical ganglion, we used quantitative enzyme radioautography with radioligands [3H]Ro41-1049 and [3H]lazabemide, respectively. Furthermore, 35S-labelled oligonucleotides complementary to isoenzyme messengerRNAs were used to map the cellular location of the respective transcripts in adjacent sections by in situ hybridization histochemistry. A markedly different pattern of distribution of the isoenzymes was observed. Highest levels of monoamine oxidase A were measured in the superior cervical ganglion, locus coeruleus, interpeduncular nucleus and ventromedial hypothalamic nucleus. The corresponding messengerRNA was detected only in the noradrenergic neurons of the superior cervical ganglion and locus coeruleus. In contrast to rat brain, monoamine oxidase B was much more abundant in most human brain regions investigated. Highest levels were measured in the ependyma of ventricles, stria terminalis and in individual hypothalamic neurons. Monoamine oxidase B transcripts were detected in serotoninergic raphe neurons, histaminergic hypothalamic neurons and in dentate gyrus granule cells of the hippocampal formation. We conclude that [3H]Ro41-1049 and [3H]azabemide are extremely useful radioligands for high-resolution analyses of the abundance and distribution of catalytic sites of monoamine oxidases A and B, respectively, in human brain sections. From levels of messenger RNA detected, the cellular sites of synthesis of the isoenzymes are the noradrenergic neurons of the locus coeruleus (for monoamine oxidase A) and the serotoninergic and histaminergic neurons of the raphe and posterior hypothalamus, respectively (for monoamine oxidase B). The combination of quantitative enzyme radioautography with in situ hybridization histochemistry is a useful approach to study, with high resolution, both the physiology and pathophysiology of monoamine oxidases in human brain.

Study on the column process of adsorption decolorization for monosodium glutamate solution in fluidized beds

The adsorption decolorization of monosodium glutamate solution employed in multiple column fluidized beds in a series is studied. The equilibrium data, the mass transfer kinetics, and fluid flow parameters are determined. A mathematics model taking into account the effects of particle size classification, particle size distribution, external and internal diffusions, and axial mixing in the liquid and solid phases is proposed, and the simulated results are in good agreement with the experimental data.

A new urea sensor based on combining the surface acoustic wave device with urease extracted from green soya bean and its application--determination of urea in human urine

The urea sensor was prepared by combining a surface acoustic wave (SAW) device, in which a SAW resonator operating at 61 MHz and a pair of parallel electrodes were used in series, with urease extracted from green soya bean. The Michaelis constant and maximum reaction rate of the urease were estimated as 2.14 mM and 27.18 kHz min-1, respectively, at pH 7.0 and 25.0 degrees C. Influences of pH, temperature and effectors on the response properties of the SAW urea sensor were investigated. Recovery of the sensor ranged from 95 to 105% and the detection limit of urea was 1.0 micrograms ml-1 (1.7 x 10(-5) M). The proposed sensor has been successfully applied to the rapid determination of urea in human urine samples. The results are consistent with the reported values and also support the clinical diagnosis.

Kinin-mediated antihypertensive effect of captopril in deoxycorticosterone acetate-salt hypertension

On the basis of evidence suggesting the activation of the kallikrein-kinin system in steroid-induced hypertension, we considered the possibility that the angiotensin-converting enzyme inhibitor captopril would lower the arterial blood pressure in deoxycorticosterone acetate (DOCA)-salt hypertensive rats through kininase II inhibition. In conscious DOCA-salt hypertensive rats with intact kidneys (n = 6) or uninephrectomized rats (n = 5), the short-term administration of captopril (8 mg/kg IV) decreased mean blood pressure from 141 +/- 3 to 118 +/- 3 mm Hg (P < .05) and from 176 +/- 12 to 158 +/- 15 mm Hg (P < .05), respectively. The maximal effect of captopril was manifested between 40 and 50 minutes after its administration, and blood pressure remained depressed for at least 2 hours. The bradykinin B2 receptor antagonist Hoe 140 (500 micrograms/kg IV) abolished the antihypertensive effect of captopril in the DOCA-salt hypertensive rats, indicating kinin involvement. Losartan, an angiotensin type 1 receptor antagonist, had no effect on blood pressure in another group of DOCA-salt hypertensive rats (n = 9) and did not significantly change the response to captopril. No effect of the angiotensin-converting enzyme inhibitor was seen in normotensive control rats (n = 5), indicating the absence of a nonspecific hypotensive action of the drug. Plasma renin activity was lower in the DOCA-salt hypertensive rats (0.7 +/- 0.2 ng angiotensin I/mL per hour, n = 4) than in normotensive control rats (8.8 +/- 1.7, n = 4). The involvement of kinins in the antihypertensive effect of captopril in DOCA-salt hypertension supports the contention that the kallikrein-kinin system contributes to blood pressure regulation in this hypertension model.

Optimal image sampling schedule: a new effective way to reduce dynamic image storage space and functional image processing time

An optimal image sampling schedule for tracer dynamic studies with positron emission tomography (PET) is proposed. This schedule incorporates the characteristics of PET measurement and uses a new cost function and the D-optimal criterion. A detailed case study of the estimation of the local cerebral metabolic rate of glucose (LCMRGLc) using the tracer fluorodeoxyglucose (FDG) and the four-parameter FDG model is presented. As the sampling schedule designed requires only four dynamic images, the storage space and data processing time are greatly reduced, while the precision of the parameter estimates is almost the same as that achieved with a commonly used schedule. The effects of intersubject and intrasubject parameter variations on parameter estimation with the use of this optimal sampling schedule are investigated by computer simulation. The simulation results show that the estimation of parameters is sufficiently robust with respect to these intersubject and intrasubject variations. The optimal sampling schedule is quite suitable therefore for PET regional parameter estimation, as well as for image-wide parameter estimation, for different subjects.

Cloning and expression of the gene encoding a novel proteinase from Tritirachium album limber

We have isolated the cDNA and the genomic clones encoding a novel serine proteinase, named proteinase T, from the fungus Tritirachium album Limber. The coding region of the gene is interrupted by two introns. The amino acid sequence of proteinase T as deduced from the nucleotide sequence is about 56% identical to that of proteinase K. Four cysteines are present in the mature proteinase, probably in the form of disulfide bonds. We have also purified the native proteinase from Tritirachium album Limber grown in the presence of 2% skim milk. Proteinase T is extremely stable at 50 degrees C. The thermal stability is not affected in the presence of 1% SDS either at pH 8.0 or 10.0. We have expressed the cDNA of proteinase T in Escherichia coli. The authenticity of the proteinase has been characterized by Western blotting and amino terminal analysis of the recombinant product. High level expression of proteinase T in E. coli as well as the refolding process to generate active proteinase will be discussed in detail.

Behaviour of surface acoustic wave interdigitated array electrode sensor in non-aqueous solution and determination of blood plasma recalcification time

A novel SAW-IDA sensor system was constructed for the first time by connecting the IDA electrodes in series with a SAW resonator. The frequency characteristics of the SAW-IDA sensor in non-aqueous solution were investigated. The effects of the parallel capacitance and cell constant were studied, and were calculated with the circuit network theory. These calculations provide guiding rules for design of the SAW-IDA sensor system. The SAW-IDA sensor was applied to determination of recalcification time and activated partial thromboplastin time of blood plasma. The sensor offers a new and effective way of studying clinical and laboratory haemostasis.

[Anti-herpes simplex virus action of combined therapy with cyclocytidine and ganciclovir]

OBJECTIVE

The study was designed to investigate the combined effect of cyclocytidine (CC) and ganciclovir (GCV) on herpes simplex virus-1 (HSV-1) in cell culture.

METHODS

The 50% inhibition concentrations of HSV-1 plaque formation (IC50) of CC, GCV alone and in combination were determined by the inhibitory test of plaque formation. The combined anti-HSV-1 effect of CC and GCV was evaluated by a graphic method and fractional inhibitory concentration (FIC) indexes.

RESULTS

IC50 of CC and GCV was 0.19 and 0.1 micrograms/ml, respectively. The combination of CC with GCV produced significantly synergistic activity against HSV-1 in cell culture. FIC indexes were all below 0.75. The combined therapy of CC and GCV can also decrease and delay the emergence of drug-resistant variants.

CONCLUSION

These results suggest that this combined therapy of CC and GCV may be a potentially effective means in the management of patients with HSV-1 ocular infection.

[Clinical study on the effect of shuxuening tablet in treatment of coronary heart disease]

Shuxuening was made of extract of Folium Ginkgo, the Shuxuening tablet No. 2 was a pure extract and No. 1 was a crude extract. Forty-six coronary heart disease patients were divided randomly into two groups according to the ratio of 2:1, Shuxuening tablet No. 1 and No. 2 were given to the two groups respectively. Results showed that both of them could alleviate the symptom of angina, the total effective rate of 2 groups were 60.00% and 83.87%, there was no significant difference between the two groups. But for the angina of middle and severe degree, the total effective rate of No. 2 was 83.33%, while that of No. 1 was 33.33%, the difference was significant (P < 0.01). They could also improve the abnormal electrocardiogram, the total effective rate of two groups were 60.00% and 74.19%, no significant difference between them was found. The two drugs could decrease the blood lipid as well.

Determination of transcription initiation sites and promoter activity of the human 5-HT2A receptor gene

The regulation of 5-HT2A receptor (5-HT2AR) expression has been implicated in a variety of pathological processes. Previous data addressing the regulation of this receptor are extremely complicated and controversial. In order to understand the mechanisms of regulation of this receptor, we have identified the promoter region of the human 5-HT2AR gene. Anchored PCR has mapped a cluster of transcription initiation sites at nucleotides -1157, -1137, -1127 (numbered sequentially as sites 1, 2 and 3). An additional initiation site (site 4) was detected at -496, 631 bp downstream of site 3. Promoter activity was defined by transfection studies. Several 5' flanking fragments linked to the human growth hormone reporter gene were transfected into two human cell lines, SHSY-5Y (neuroblastoma) and HeLa (cervix carcinoma) which express 5-HT2AR. A 0.74 kb HaeIII/PvuII fragment, which encompasses the initiation sites 1 to 3 and 5' of the downstream initiation site 4, exhibited significant promoter activity in both cell lines. Inclusion of additional sequences upstream (the 1.6 kb PvuII/PvuII fragment) had little effect on the promoter activity, but the extension of the 0.74 kb fragment downstream to include a 0.45 kb PvuII/SmaI fragment drastically decreased the promoter activity. These results suggest that the promoter activity for human 5-HT2AR gene resides in the 0.74 kb HaeIII/PvuII fragment and the 0.45 kb PvuII/SmaI fragment may contain a silencer for the gene expression.

The human urinary epidermal growth factor (EGF) precursor. Isolation of a biologically active 160-kilodalton heparin-binding pro-EGF with a truncated carboxyl terminus

In this report, we describe the isolation from human urine of a predominant 160-kDa epidermal growth factor (EGF)-immunoreactive glycoprotein that exhibits affinity for heparin. The purification procedure involved concentration and dialysis of 20-30-liter batches of fresh urine on a high capacity ultrafiltration apparatus followed by chromatography on DEAE-Sephacel, heparin-agarose, and Sephacryl S-300. A nearly homogeneous preparation of 160-kDa protein was obtained with a yield of approximately 1 mg of 160-kDa protein from 25 liters of urine. The amino-terminal sequence of the purified 160-kDa protein, H2N-SAPQHXSXPEGTXA-, matched residues 21-34 of the predicted sequence of human prepro-EGF and established that the 160 kDa protein (pro-EGF) is a product of the prepro-EGF gene. Characterization of the carboxyl terminus of the purified protein by digestion with carboxypeptidase B and by immunoblotting with antisera against synthetic carboxyl-terminal and juxtatransmembrane peptides of prepro-EGF indicated that the carboxyl terminus has been truncated at an arginine residue that corresponds, most likely, to the carboxyl-terminal arginine of the EGF moiety. The intact 160-kDa pro-EGF is biologically active as evidenced by its specific binding to the EGF receptor and activation of the EGF receptor tyrosine kinase in A-431 cell membranes. Purified pro-EGF competitively inhibited the binding of 125I-EGF to human fibroblasts, and it stimulated the proliferation of these cells in culture. When immobilized onto culture dishes, the heparin-binding pro-EGF appeared to function both as an adhesion molecule and as a growth factor for serum-free mouse embryo cells.

Regulated secretion of prolactin by the mouse insulinoma cell line beta TC-3

Our aim is to use cultured cells capable of regulated protein secretion for the production of recombinant proteins that require particular types of post-translational modifications. Here we have generated a stable transfected beta TC-3 cell line, beta TC-IPR9, that secretes high levels of recombinant prolactin. Transfected cells synthesize both the 27 kDa glycosylated and a 23 kDa nonglycosylated prolactin; the 23 kDa nonglycosylated species was secreted preferentially when cells were placed in secretion medium containing isobutylmethylxanthine (IBMX) and high concentrations of glucose, K+, and Ca2+. When the cells were cultured in medium containing low concentrations of glucose, K+, and Ca2+, most of the prolactin and insulin were not secreted; much of the prolactin was proteolytically converted to a 16 kDa form. Within the first 30 minutes after transferring the cells to medium containing secretagogues there was a 20-fold increase in the rate of secretion of prolactin; all of the 16 kDa species was secreted. The recombinant cells could be cycled several times between medium in which prolactin was biosynthesized and medium in which it was secreted. Preferential secretion of proteolytically processed prolactin in a medium without contaminating proteins offers an example of the advantage of this technology for production of other recombinant proteins.

Anti-AIDS agents--XIX. Neotripterifordin, a novel anti-HIV principle from Tripterygium wilfordii: isolation and structural elucidation

A new kaurane type diterpene lactone, neotripterifordin (1), has been isolated from the roots of Tripterygium wilfordii. The structure of 1 was elucidated by spectroscopic methods, which included the concerted application of a number of 2-D NMR techniques including 1H-1H COSY, phase-sensitive NOESY, HETCOR, and long-range HETCOR. Compound 1 showed potent anti-HIV replication activity in H9 lymphocyte cells with an EC50 of 25 nM and TI of 125.

Angiotensin II-mediated renal vasoconstriction amenable to alpha 1-adrenoceptor blockade

Renal adrenergic interactions of intravenously and intrarenal arterially administered angiotensin II were studied in the anesthetized rabbit. Systemic arterial blood pressure and left renal blood flow were monitored. Bolus doses of angiotensin II, 50 and 100 ng/kg given intravenously, caused an immediate reduction in renal blood flow followed by a more sustained vasoconstrictor response. Prazosin, 5 micrograms/kg/min, infused intrarenal arterially, decreased both components of the reduced renal blood flow, suggesting adrenergic contribution to the response. Renal denervation reduced significantly the immediate response to angiotensin II without affecting the sustained response; administration of prazosin after denervation caused a further decrease in the response. Left adrenalectomy had no significant effect on the angiotensin II-induced renal blood flow response, ruling out the possible contribution of adrenal catecholamine release via the adrenal rete. In animals that had undergone renal denervation and left adrenalectomy, the renal blood flow response to intrarenal arterial injection of subpressor doses of angiotensin II (5 and 10 ng/kg) was reduced by the infusion of prazosin. It is concluded that angiotensin II-induced renal vasoconstriction is contributed to by adrenergic actions dependent in part on intact renal nerves, but also by a component not requiring an intact nerve supply.

Localization of protein disulfide isomerase to the external surface of the platelet plasma membrane

Protein disulfide isomerase (PDI) is an enzyme that catalyzes the formation as well as the isomerization of disulfide bonds. In this study, antibodies against PDI were used to show PDI antigen on the platelet surface by indirect immunofluorescence microscopy and by flow cytometry. The platelets were not activated, as evidenced by the absence of staining by an antibody against P-selectin. Permeabilized platelets showed little cytosolic PDI by indirect immunofluorescence microscopy, suggesting that the majority of platelet PDI is localized to the platelet surface. PDI activity against "scrambled" RNase was shown with intact platelets. The activity was inhibited by inhibitors of PDI and by an antibody against PDI. Other blood cells showed little PDI. Platelet surface PDI may play a role in the various physiological and pathophysiologic processes in which platelets are involved.

Muscarinic receptor subtypes in rat dorsal cochlear nucleus

We previously reported that responses of spontaneously active rat dorsal cochlear nucleus (DCN) neurons to cholinergic agonists are mediated predominantly by muscarinic receptors. We have now tested the effects of 7 antagonists with differing affinities for the muscarinic receptor subtypes M1-M4 on the responses to constant, submaximal doses of carbachol in rat brainstem slices. Each slice was exposed to one or more concentrations of one antagonist applied during extracellular recording of a DCN neuron. The concentrations yielding 50% reduction of test responses (IC50) of regular and bursting neurons were estimated for each antagonist. Correlation coefficients were calculated between log(IC50) values and log(Ki) values of the drugs for the receptor subtypes. Correlation coefficients for both regular and bursting neurons were not significant (P > 0.05) for M1 and M3, but were significant (P < 0.02) for M4. Bursting but not regular neurons also showed a significant correlation for M2 (P < 0.05). Our results suggest that (1) M4 contributes to the cholinergic responses in DCN and M2 may also contribute to the responses of bursting neurons, but the contribution of other subtypes cannot be completely excluded; (2) muscarinic subtypes in DCN probably differ from those reported for cochlea and some brain regions.

Pharmacokinetics of tablet huperzine A in six volunteers

AIM

To study pharmacokinetics of tablet huperzine A (Hup-A) in Chinese volunteers to help establishing its drug administration schedule.

METHODS

For 6 volunteers after a single oral dose of 0.99 mg, drug concentrations in plasma were assayed by reverse phase high pressure liquid chromatography (HPLC) at 0.5, 0.75, 1.0, 1.25, 1.5, 2, 4, 6, 8, and 10 h. The pharmacokinetic parameters were calculated with a 3P87 program by computer.

RESULTS

The time course of plasma concentrations conformed to a one-compartment open model with a first order absorption. The pharmacokinetic parameters were as follows: T 1/2ka = 12.6 min, T 1/2ke = 288.5 min, Tmax = 79.6 min, Cmax = 8.4 micrograms L-1, AUC = 4.1 mg L-1 min.

CONCLUSION

Hup-A was absorbed rapidly, distributed widely in the body, and eliminated at a moderate rate.

Contrasting roles for Myc and Mad proteins in cellular growth and differentiation

The positive effects of Myc on cellular growth and gene expression are antagonized by activities of another member of the Myc superfamily, Mad. Characterization of the mouse homolog of human mad on the structural level revealed that domains shown previously to be required in the human protein for anti-Myc repression, sequence-specific DNA-binding activity, and dimerization with its partner Max are highly conserved. Conservation is also evident on the biological level in that both human and mouse mad can antagonize the ability of c-myc to cooperate with ras in the malignant transformation of cultured cells. An analysis of c-myc and mad gene expression in the developing mouse showed contrasting patterns with respect to tissue distribution and developmental stage. Regional differences in expression were more striking on the cellular level, particularly in the mouse and human gastrointestinal system, wherein c-Myc protein was readily detected in immature proliferating cells at the base of the colonic crypts, while Mad protein distribution was restricted to the postmitotic differentiated cells in the apex of the crypts. An increasing gradient of Mad was also evident in the more differentiated subcorneal layers of the stratified squamous epithelium of the skin. Together, these observations support the view that both downregulation of Myc and accumulation of Mad may be necessary for progression of precursor cells to a growth-arrested, terminally differentiated state.

Acute myeloid leukemia and myelodysplasia following intensive chemotherapy for breast cancer

Two major classes of therapy-related acute myeloid leukemias (t-AML) and myelodysplastic syndromes (t-MDS) have been described following the use of conventional doses of alkylating agents and epipodophyllotoxins. They are characterized by distinct clinical presentations and chromosomal abnormalities. We report 2 cases of t-AML and 1 case of t-MDS in 3 out of 36 women who underwent high-dose chemotherapy and attempted ABMT for breast cancer. Two patients developed t-AML 4 and 8 months following the initiation of high-dose chemotherapy with or without ABMT. The third patient developed t-MDS 23 months following dose-intensive chemotherapy and ABMT. Cytogenetic studies of the marrow metaphase chromosomes from the two patients who developed t-AML, including FISH analysis in 1 patient, showed a t(9;11)(p22ng,q23) abnormal chromosome 6 (ring chromosome). Neither patient had a preleukemic phase. Cytogenetic studies from the third patient who developed t-MDS showed abnormalities of chromosome 5 (-5) and a derivative of chromosome 17. The use of multiple chemotherapeutic agents in all 3 patients makes it difficult to attribute the development of these cases of t-MDS/t-AML to a single chemotherapeutic agent. The possible role of dose-intensive chemotherapy in the development of these secondary malignancies is discussed.

Characterization of the human 5-HT2A receptor gene promoter

The regulation of 5-HT2A receptor (5-HT2AR) expression has been implicated in a variety of pathological processes and has been shown to be extremely complicated and controversial. In order to understand the mechanisms of regulation of this receptor, it is important to characterize its promoter. In this report, the 5' end of the human 5-HT2AR gene was cloned and characterized. Anchored PCR mapped multiple transcription initiation sites at nucleotides -1157, -1137, -1127, and -496. Transfection of chimeric growth hormone plasmids containing various DNA fragments into 5-HT2AR-positive human cell lines (SHSY-5Y, neuroblastoma; HeLa, cervix carcinoma) showed that the 0.74 kb HaeIII/PvuII fragment, which encompasses the initiation sites between -1157 and -1127 and 5' of the downstream initiation site (at -496), exhibited significant promoter activity. This promoter activity was not affected by the sequence upstream of the 0.74 kb fragment. The sequence downstream (the 0.45 kb PvuII/SmaI fragment) strongly repressed this promoter activity, suggesting the presence of a silencer. Sequence analysis combined with gel retardation and Dnase 1 footprinting assay identified multiple cis and trans elements for this fragment, including Sp1, PEA3, cyclic AMP response element (CRE)-like sequence, and E-boxes. Two novel transcription factors have been detected by gel retardation and DNase 1 footprinting assay; one of them may be specific for human. The transcription factors and promoter activities were low in the negative cell line NCI-H460 (human lung large cell carcinoma). Interestingly, the 0.39 kb fragment, isolated from the 3' end of the 0.74 kb fragment, exhibited the highest promoter activity. The possibility that this 0.39 kb fragment may be an alternative promoter is discussed. These new data are essential for further study of the regulation of 5-HT2AR gene expression.

Aggressive behavior and altered amounts of brain serotonin and norepinephrine in mice lacking MAOA

Deficiency in monoamine oxidase A (MAOA), an enzyme that degrades serotonin and norepinephrine, has recently been shown to be associated with aggressive behavior in men of a Dutch family. A line of transgenic mice was isolated in which transgene integration caused a deletion in the gene encoding MAOA, providing an animal model of MAOA deficiency. In pup brains, serotonin concentrations were increased up to ninefold, and serotonin-like immunoreactivity was present in catecholaminergic neurons. In pup and adult brains, norepinephrine concentrations were increased up to twofold, and cytoarchitectural changes were observed in the somatosensory cortex. Pup behavioral alterations, including trembling, difficulty in righting, and fearfulness were reversed by the serotonin synthesis inhibitor parachlorophenylalanine. Adults manifested a distinct behavioral syndrome, including enhanced aggression in males.

Characterization of protein disulphide isomerase released from activated platelets

Protein disulphide isomerase (PDI) activity is released by activated platelets. In this study, PDI was purified from platelets and found to have an apparent mass, pI and N-terminal sequence similar to those for other human PDIs. Rabbit antibodies were generated and used to establish that, on activation, platelets release a protein immunologically identical to PDI in platelets. Approximately 10% of total platelet PDI was released by thrombin and 20% by calcium ionophore. The antibody was used to demonstrate PDI on the external surface of platelets by electron microscopy. Flow cytometry was used to demonstrate that upon activation of platelets with ionophore PDI was released by vesiculation. Since platelets are present and become activated at sites of vascular injury, platelet PDI may play a role in the various haemostatic and tissue remodelling processes in which platelets are involved.

Epidermal growth factor induces the tyrosine phosphorylation and nuclear translocation of Stat 5 in mouse liver

Intraperitoneal injection of epidermal growth factor into mice results in the appearance of multiple tyrosine-phosphorylated proteins in liver nuclei within minutes after administration. We have previously identified three of these proteins as Stat 1 alpha, Stat 1 beta (p91, p84), and Stat 3 (p89). In the present report we demonstrate that Stat 5 (p92), the recently described prolactin inducible transcription factor detected in mammary glands, is the major tyrosine-phosphorylated protein translocated to the nucleus in mouse liver in response to epidermal growth factor. Furthermore, gel-shift analysis and affinity purification revealed that Stat 5, Stat 1 alpha, and Stat 1 beta specifically bind to the prolactin inducible element upstream of the beta-casein promoter.

[Studies on diagnostic bacteriophage of Vibrio fluvialis]

Species of Vibrio fluvialis are identified by their biochemical characteristics so far, with a lot of items to be determined, overelaborate procedure and expensiveness. Inaccordance with the fact that bacteriophage is a specific parasite inhabited in bacteria and has been used in identifying other bacteria with high specificity, some of Vibrio fluvialis bacteriophage isolated from natural environment were selected to make diagnostic preparation for Vibrio fluvialis identification. Diagnostic positivity of Vibrio fluvialis averaged 84.27%, and 87.84% for those of human source. Cross-lysis rates both for the same Vibrio genus and that of different families in the same genus were less then 3%, and no cross-lysis was found for the other enteric bacteria in different genera. There was no significant difference between diagnostic bacteriophage and biochemical tests for Vibrio of unknown species. This method was highly specific, sensitive, rapid, simple and inexpensive, and could be used in diagnosis of Vibrio fluvialis.

Assay of pancreatic lipase with the surface acoustic wave sensor system

A new type of surface acoustic wave sensor system for assaying the activity of pancreatic lipase has been proposed. The assay of this enzyme is based on the change in conductance of the solution caused by the release of a fatty acid, using triolein as a substrate. A linear relationship between frequency response and enzyme concentration is obtained. Kinetic parameters of pancreatic lipase, i.e., the Michaelis constant for triolein and the corresponding maximum initial rate, are estimated to be 5.46 mM and 7551.6 Hz/min, respectively. The effects of temperature and pH value are also investigated.

Antitumor agents, 154. Cytotoxic and antimitotic flavonols from Polanisia dodecandra

Three flavonols, 5,3'-dihydroxy-3,6,7,8,4'-pentamethoxyflavone [1], 5,4'-dihydroxy-3,6,7,8,3'-pentamethoxyflavone [2], and quercetin 3-O-beta-D-glucopyranosyl-7-O-alpha-L-rhamnopyranoside [3], were isolated from Polanisia dodecandra. Compound 1 showed remarkable cytotoxicity in vitro against panels of central nervous system cancer (SF-268, SF-539, SNB-75, U-251), non-small cell lung cancer (HOP-62, NCI-H266, NCI-H460, NCI-H522), small cell lung cancer (DMS-114), ovarian cancer (OVCAR-3, SK-OV-3), colon cancer (HCT-116), renal cancer (UO-31), a melanoma cell line (SK-MEL-5), and two leukemia cell lines (HL-60 [TB], SR), with GI50 values in the low micromolar to nanomolar concentration range. This substance also inhibited rubulin polymerization (IC50 = 0.83 +/- 0.2 microM) and the binding of radiolabeled colchicine to tubulin with 59% inhibition when present in equimolar concentrations with colchicine. Compound 2 also showed cytotoxicity against medulloblastoma (TE-671) tumor cells with an ED50 value of 0.98 microgram/ml. Compound 1 appears to be the first example of a flavonol to exhibit potent inhibition of tubulin polymerization and, therefore, warrants further investigation as an antimitotic agent.

The isolation and structural elucidation of three new neolignans, piperulins [corrected] A, B, and C, as platelet activating factor receptor antagonists from Piper puberulum

Three new neolignans, piperulins [corrected] A [1], B [2], and C [3], were isolated from Piper puberulum. Their structures and relative stereochemistries were determined from spectral data and the X-ray crystallographic analysis of 1. Compounds 1 and 3 inhibit specific platelet activating factor receptor binding with IC50 values of 7.3 and 5.7 microM, respectively.

An amino-terminal domain of Mxi1 mediates anti-Myc oncogenic activity and interacts with a homolog of the yeast transcriptional repressor SIN3

Documented interactions among members of the Myc superfamily support a yin-yang model for the regulation of Myc-responsive genes in which transactivation-competent Myc-Max heterodimers are opposed by repressive Mxi1-Max or Mad-Max complexes. Analysis of mouse mxi1 has led to the identification of two mxi1 transcript forms possessing open reading frames that differ in their capacity to encode a short amino-terminal alpha-helical domain. The presence of this segment dramatically augments the suppressive potential of Mxi1 and allows for association with a mammalian protein that is structurally homologous to the yeast transcriptional repressor SIN3. These findings provide a mechanistic basis for the antagonistic actions of Mxi1 on Myc activity that appears to be mediated in part through the recruitment of a putative transcriptional repressor.