Application of two-photon laser-induced fluorescence for single-shot visualization of carbon monoxide in a spark ignited engine

Carbon monoxide detection through the use of two-photon laser-induced fluorescence (LIF) has been investigated for engine diagnostics applications. Two-dimensional single-shot LIF imaging of CO was achieved in a spark ignited (SI) engine. The interference from C2 and photolysis of hot CO2 was found to be negligible through the spectrally and spatially resolved measurements.

Preparation of bioactive nanotitania ceramics with biomechanical compatibility

In this article, bioactive nanotitania ceramics with biomechanical compatibility was prepared by using an additive of hydroxyapatite or MgO as particle growth inhibitor. After sintering at 1000 degrees C, the particle size of nanotitania ceramics prepared by using HA as additive (HT) was much smaller than that prepared by using MgO as additive (MT). In simulated body fluid (SBF), HT could induce apatite formation in 4 days, while no apatite could be found on MT even after it was soaked in SBF for 14 days. After Ros17/28 osteoblasts were cultured on the materials for 1, 4, and 6 days, MTT results showed that the osteoblasts on the HT differentiated faster than that on the MT. Mechanical tests results showed that the bending and compressive strength of HT were 160 and 200 MPa, while those of MT were 70 and 88 MPa, respectively. These results demonstrated that it is suitable to prepare bioactive nanotitania ceramics, with biomechanical compatibility, by using HA as particle growth inhibitor.

Enteric dopaminergic neurons: definition, developmental lineage, and effects of extrinsic denervation

The existence of enteric dopaminergic neurons has been suspected; however, the innervation of the gut by sympathetic nerves, in which dopamine (DA) is the norepinephrine precursor, complicates analyses of enteric DA. We now report that transcripts encoding tyrosine hydroxylase (TH) and the DA transporter (DAT) are present in the murine bowel (small intestine > stomach or colon; proximal colon > distal colon). Because sympathetic neurons are extrinsic, transcripts encoding TH and DAT in the bowel are probably derived from intrinsic neurons. TH protein was demonstrated immunocytochemically in neuronal perikarya (submucosal >> myenteric plexus; small intestine > stomach or colon). TH, DA, and DAT immunoreactivities were coincident in subsets of neurons (submucosal > myenteric) in guinea pig and mouse intestines in situ and in cultured guinea pig enteric ganglia. Surgical ablation of sympathetic nerves by extrinsic denervation of loops of the bowel did not affect DAT immunoreactivity but actually increased numbers of TH-immunoreactive neurons, expression of mRNA encoding TH and DAT, and enteric DOPAC (the specific dopamine metabolite). The fetal gut contains transiently catecholaminergic (TC) cells. TC cells are the proliferating crest-derived precursors of mature neurons that are not catecholaminergic and, thus, disappear after embryonic day (E) 14 (mouse) or E15 (rat). TC cells appear early in ontogeny, and their development/survival is dependent on mash-1 gene expression. In contrast, the intrinsic TH-expressing neurons of the murine bowel appear late (perinatally) and are mash-1 independent. We conclude that the enteric nervous system contains intrinsic dopaminergic neurons that arise from a mash-1-independent lineage of noncatecholaminergic precursors.

One-week regimens containing ranitidine bismuth citrate, furazolidone and either amoxicillin or tetracycline effectively eradicate Helicobacter pylori: a multicentre, randomized, double-blind study

BACKGROUND

The metronidazole resistance of Helicobacter pylori strains has increased rapidly.

AIM

To evaluate the efficacy and safety of new 1-week regimens containing ranitidine bismuth citrate, furazolidone and either amoxicillin or tetracycline.

METHODS

One hundred and twenty patients with H. pylori-positive inactive duodenal ulcer or non-ulcer dyspepsia diagnosed by endoscopy were recruited randomly to receive one of two regimens for 7 days: ranitidine bismuth citrate, 350 mg b.d., furazolidone, 100 mg b.d., and either amoxicillin, 1000 mg b.d. (n=60), or tetracycline, 500 mg b.d. (n=60). H. pylori infection was identified by rapid urease testing and histology. 13C-Urea breath test was performed to evaluate the cure of H. pylori infection at least 4 weeks after completion of triple therapy.

RESULTS

The eradication rates of H. pylori by ranitidine bismuth citrate-furazolidone-amoxicillin and ranitidine bismuth citrate-furazolidone-tetracycline regimens were 82% and 85% (P > 0.05), respectively, by intention-to-treat analysis, and 85% and 91% (P > 0.05), respectively, by per protocol analysis. Adverse effects were mild in both ranitidine bismuth citrate-furazolidone-amoxicillin and ranitidine bismuth citrate-furazolidone-tetracycline groups.

CONCLUSIONS

One-week regimens containing ranitidine bismuth citrate, furazolidone and amoxicillin or tetracycline are well tolerated and effective for the eradication of H. pylori.

SiCNN--a new stable isomer with Si(triple bond)C triple bonding

To predict potentially stable molecules with Si(triple bond)C triple bonding, theoretical calculations at the B3LYP/ 6-311G(d) and CCSD(T)/6-311G(2df) (single-point) levels were employed to study the structures, energetics, and isomerization of various SiCN2 isomers. A schematic potential energy surface (PES) of SiCN2 was established to discuss the kinetic stability of the isomers. A new isomer SiCNN was found to possess a typical Si(triple bond)C triple bond, as confirmed by comparative calculations at the B3LYP, QCISD, QCISD(T), CCSD, and CCSD(T) levels on the bond lengths of SiCNN and other experimentally or theoretically known species of RSiCH (R = H, F, Cl, OH). Moreover, SiCNN resides in a very deep potential, the stabilization barrier is at least 53.2 kcal mol(-1). Thus, SiCNN may be considered as the most kinetically stable isomer with Si(triple bond)C triple bonding known to date, and it may represent a very promising molecule for future experimental characterization. In addition, the stability of the other isomers, such as the four linear species SiNCN, SiNNC, NSiCN and NSiNC, a three-membered NNC ring isomer with exocyclic C-Si bonding, and a four-membered SiCNN ring isomer is discussed and compared with SiCNN.

Enhanced multispecificity of arabidopsis vacuolar multidrug resistance-associated protein-type ATP-binding cassette transporter, AtMRP2

Recent investigations have established that Arabidopsis thaliana contains a family of genes encoding ATP-binding cassette transporters belonging to the multidrug resistance-associated protein (MRP) family. So named because of the phenotypes conferred by their animal prototypes, many MRPs are MgATP-energized pumps active in the transport of glutathione (GS) conjugates and other bulky amphipathic anions across membranes. Here we show that Arabidopsis MRP2 (AtMRP2) localizes to the vacuolar membrane fraction from seedlings and is not only competent in the transport of GS conjugates but also glucuronate conjugates after heterologous expression in yeast. Based on the stimulatory action of the model GS conjugate 2,4-dinitrophenyl-GS (DNP-GS) on uptake of the model glucuronide 17beta-estradiol 17-(beta-d-glucuronide) (E(2)17betaG) and vice versa, double-label experiments demonstrating that the two substrates are subject to simultaneous transport by AtMRP2 and preloading experiments suggesting that the effects seen result from cis, not trans, interactions, it is inferred that some GS conjugates and some glucuronides reciprocally activate each other's transport via distinct but coupled binding sites. The results of parallel experiments on AtMRP1 and representative yeast and mammalian MRPs indicate that these properties are specific to AtMRP2. The effects exerted by DNP-GS on AtMRP2 are not, however, common to all GS conjugates and not simulated by oxidized glutathione or reduced glutathione. Decyl-GS, metolachlor-GS, and oxidized glutathione, although competitive with DNP-GS, do not promote E(2)17betaG uptake by AtMRP2. Reduced glutathione, although subject to transport by AtMRP2 and able to markedly promote E(2)17betaG uptake, neither competes with DNP-GS for uptake nor is subject to E(2)17betaG-promoted uptake. A multisite model comprising three or four semi-autonomous transport pathways plus distinct but tightly coupled binding sites is invoked for AtMRP2.

[Fluorescence in situ hybridization applied to the meiotic analysis and spontaneous chromosome translocation in the pollen mother cells of hybrids of Triticum-Haynaldia]

Fluorescence in situ hybridization was applied to the meiotic analysis and chromosome pairing in the pollen mother cells of hybrids of Triticum-Haynaldia. The results indicated that most (90.5%-93.2%) of the PMCs of two Triticum-Haynaldia hybrids contained two univalents involving one Haynaldia chromosome at metaphase I, and only 1 of 320 PMCs with homologous pairing between one wheat chromosome and one Haynaldia chromosome was observed in the hybrid of Guinong 22 x common wheat Chinese Spring, the frequency was 0.3%. The frequencies of the PMCs with mis-dividing chromosome ranged from 32.7% to 37.5% at anaphase I and from 20.5% to 24.4% at anaphase II in the hybrids between Triticum-Haynaldia. The frequency of Haynaldia chromatin translocating into Triticum chromosome was about 0.7% at anaphase I in the hybrid of Guinong 22 x common wheat Chinese Spring and was 0.8%-1.7% at anaphase II in two wheat-Haynaldia hybrids. Otherwise, the chromosome morphology involving Haynaldia chromatin was observed at preleptotene I, and the frequencies of chromatin nucleus at tetrad stage and at microspore stage were investigated. The time of chromosome translocation in meiosis and the transmitting frequencies of Haynaldia chromosome in wheat background were discussed.

[Genetic analysis for introgressive genes of petal color from Gossypium bickii to G. hirsutum L]

The character of red petals with a large basal spot was transferred from Gossypium bickii into G. hirsutum L., and the pure lines (HBRL) with the character were obtained by Liang Zhenglan in 1988. Results of genetic analysis for G. hirsutum pure line of red petals (R3bic) and large basal spot (R2bic) were reported in the present study. The large basal spot was dominant to the small basal-spot and spotlessness of G. hirsutum. R2bic was shown to be allelic to R2 of G. hirsutum, and R2bic, R2 and r2 were multiple alleles. R2bic was found to be linked with Lc1, and linkage between R2bic and Lc1 was estimated at 37.31 +/- 2.44 centimorgans, The red petal (R3bic) was epistatic dominance to the yellow petal (Y1) and cream petal (y1), and R3bic is closely linked with R2bic. It is proposed that the introgressive gene of the large basal spot from G. bickii into G. hirsutum be assigned gene symbol R2bic, and the red petals be given the gene symbol R3bic.

[The genetic behavior of an Agropyron intermedium chromosome conferring BYDV resistance in wheat background]

Based on the chromosome origin identification of an Agropyron intermedium chromosome with BYDV resistance in Yi4212, a BYDV-resistant substitution line derived from the hybrids between 77-5433 and Zhong5, its ability compensating the lost wheat chromosomes and its transmission rate were investigated. The results indicated that the BYDV-resistant chromosomes originated from Zhong 5 could compensate the wheat chromosomes of homotologous group 2, 5 and 7. The chromosome conferring resistance to BYDV showed the intendance to substitute 2D rather than 2A, 2B wheat chromosomes in disomic substitution lines. In (77-5433/Zhong 5) selfing F2 population, 10 kinds of chromosome constitutions, including 9 expected and 1 unexpected kinds, and much chromosome number variation and little chromosome structure variation were observed. The transmission rate of the BYDV-resistant chromosome and the gametes carrying this chromosome were 56.3% and 33.0% respectively, both are lower than the expected ratio 75.0% and 50.0%. Some reasons were given to explain the related results, and chromosome in situ hybridization was an efficient and accurate way in studying the alien chromosome behavior in wheat background.

[Genetical effect of different rye chromosomes on the acid phosphatase (Acph) secretion of common wheat roots under phosphorus starvation conditions]

The effects of different rye chromosomes on Acph secretion of common wheat roots under P starvation conditions were studied by using a set of Chinese Spring-Imperial (CS-IMP) alien addition lines as materials. The Acph activity measurement results showed that P starvation is an induction factor for Acph gene expression; Different chromosomes of Imperial rye in Chinese Spring background has different effects on the secretion of Acph by corresponding addition line roots. Among them, chromosome 1R had the strongest promoting effect; The IEF diagram of Acph isozymes clearly demonstrated that chromosome 1R in rye genome carries P starvation inducible Acph gene(s).

[Measurement for relative molecular mass distribution of lignin dispersants]

Gel chromatography was employed to measure relative molecular mass distribution of lignin dispersants. The results show that relative molecular mass distribution of Reax-85A(I) and M-9(II) are respectively to be from 500 to 35,000 and from 1,000 to 50,000. The fractions separated from (I) and (II) by thin layer chromatography were also investigated through gel chromatography to prove that these fractions were mainly separated depending on relative molecular mass.

Inputs from intrinsic primary afferent neurons to nitric oxide synthase-immunoreactive neurons in the myenteric plexus of guinea pig ileum

Nitric oxide synthase (NOS) immunoreactivity occurs in two groups of neurons in the guinea pig small intestine: descending interneurons that are also immunoreactive for choline acetyltransferase (ChAT), and inhibitory motor neurons that lack ChAT immunoreactivity. Interneurons that are involved in local reflexes would be expected to have inputs from intrinsic primary afferent (sensory) neurons, most of which are calbindin-immunoreactive. We examined this possibility using triple staining for NOS, ChAT and calbindin immunoreactivity and investigated the relationships between calbindin-immunoreactive varicosities and the cell bodies of NOS-immunoreactive neurons, using high-resolution confocal microscopy and electron microscopy. By confocal microscopy, we found that the cell bodies of ChAT/NOS interneurons received 84 +/- 23 (mean +/- SD) direct appositions from calbindin-immunoreactive varicosities and that the cell bodies of NOS-inhibitory motor neurons received 82 +/- 20 appositions. Electron-microscopic examination of the relations of 265-calbindin-immunoreactive varicosities, at distances within the resolution of the confocal microscope (300 nm), to 30 NOS-immunoreactive nerve cells indicated that 84% formed close contacts or synapses and 16% were separated from neurons by thin glial cell processes. Thus, each NOS-immunoreactive nerve cell receives about 70 synaptic inputs or close contacts from the calbindin-immunoreactive varicosities of intrinsic primary afferent neurons. It is concluded that there are monosynaptic reflex connections in which intrinsic primary afferent neurons synapse directly with motor neurons and di- or poly-synaptic reflexes in which ChAT- and NOS-immunoreactive neurons are interneurons, interposed between intrinsic primary afferent neurons and NOS-inhibitory neurons.

Role of deoxyribonucleoside triphosphates (dNTPs) in cell transformation

Deoxyribonucleoside triphosphate (dNTP) pools were measured in normal BALB/c3T3 cells, transformation-treated cells and transformed cells with reverse-phase HPLC. The fluctuation of dNTP pools was similar after transformation treatment with alkylating mutagen glycidyl methacrylate (GMA) or Nmethyl-N'-nitro-N-nitrosoguanidine (MNNG). However, the gap between deoxyguanosine triphosphate + deoxyadenosine triphosphate (dGTP + dATP) pools and deoxythymidine triphosphate + deoxycytidine triphosphate (dTTP + dCTP) pools was greatly intensified. The measurements also indicated that the dNTP pools in transformed cells were quite different from those in normal cells. The results suggested that dNTP pools may play an important role in cell transformation.

Role of dNTPs in mutagenesis

The induced mutation frequency by alkylating mutagen glycidyl methacrylate (GMA) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was investigated with or without perturbation of deoxyribonucleoside triphosphate (dNTP) pools; the influence of short treatment at different concentrations of GMA or MNNG on dNTP pools was also explored. The results indicated that the induced mutation frequency increased greatly at high dosages of mutagen (GMA approximately 64 micrograms/ml, MNNG approximately 8 micrograms/ml) and the perturbation on dNTP pools was carried out before the treatment of mutagen; the short treatment with mutagen could induce distinct fluctuations of dNTP pools, but different mutagen might have different effects on dNTP pools. According to the results of the present study and other reports in literature, we conclude that dNTP pools may be the targets of alkylating mutagens and the fluctuations of dNTP pools are closely associated with mutagenesis.

Immunohistochemical localisation of cholinergic markers in putative intrinsic primary afferent neurons of the guinea-pig small intestine

Antibodies against choline acetyltransferase (ChAT) and the vesicular acetylcholine transporter (VAChT) were used to determine whether neurons that have previously been identified as intrinsic primary afferent neurons in the guinea-pig small intestine have a cholinergic phenotype. Cell bodies of primary afferent neurons in the myenteric plexus were identified by their calbindin immunoreactivity and those in the submucous plexus by immunoreactivity for substance P. High proportions of both were immunoreactive for ChAT, viz. 98% of myenteric calbindin neurons and 99% of submucosal substance P neurons. ChAT immunoreactivity also occurred in all nerve cell bodies immunoreactive for calretinin and substance P in the myenteric plexus, but in only 16% of nerve cells immunoreactive for nitric oxide synthase. VAChT immunoreactivity was in the majority of calbindin-immunoreactive varicosities in the myenteric ganglia, submucous ganglia and mucosa and also in the majority of the varicosities of neurons that were immunoreactive for calretinin and somatostatin and that had been previously established as being cholinergic. We conclude that the intrinsic primary afferent neurons are cholinergic and that they may release transmitter from their sensory endings in the mucosa.

Morphological and immunohistochemical identification of neurons and their targets in the guinea-pig duodenum

Nerve circuits within the proximal duodenum were investigated using a combination of immunohistochemistry for individual neuron markers and lesion of intrinsic nerve pathways to determine axon projections. Cell shapes and axonal projections were also studied in cells that had been injected with a marker substance. Several major neuron populations were identified. Calbindin immunoreactivity occurred in a population of myenteric nerve cells with Dogiel type II morphology. These had axons that projected to other myenteric ganglia, to the circular muscle and to the mucosa. All were immunoreactive for the synthesizing enzyme for acetylcholine, choline acetyltransferase, and some were also immunoreactive for calretinin. Myenteric neurons with nitric oxide synthase immunoreactivity projected anally to the circular muscle. These were also immunoreactive for vasoactive intestinal peptide, and proportions of them had enkephalin and/or neuropeptide Y immunoreactivity. It is suggested that they are inhibitory motor neurons to the circular muscle. A very few (about 2%) of nitric oxide synthase-immunoreactive neurons had choline acetyltransferase immunoreactivity. Tachykinin (substance P)-immunoreactive nerve cells were numerous in the myenteric plexus. Some of these projected orally to the circular muscle and are concluded to be excitatory motor neurons. Others projected to the tertiary plexus which innervates the longitudinal muscle and others provided terminals in the myenteric plexus. Two groups of descending interneurons were identified, one with somatostatin immunoreactivity and one with vasoactive intestinal peptide immunoreactivity. The two most common nerve cells in submucous ganglia were neuropeptide Y- and vasoactive intestinal peptide-immunoreactive nerve cells. Both provided innervation of the mucosa. There was also a population of calretinin-immunoreactive submucous neurons that innervated the mucosal glands, but not the villi. Comparison with the ileum reveals similarities in the chemistries and projections of neurons. Differences include the almost complete absence of nitric oxide synthase immunoreactivity from vasoactive intestinal peptide-immunoreactive interneurons in the duodenum, the projection of calbindin-immunoreactive Dogiel type II neurons to the circular muscle and the absence of tachykinin-immunoreactivity from these neurons.

The diagnostic value of transendoscopic miniature ultrasonic probe for esophageal diseases

BACKGROUND AND STUDY AIMS

To investigate the value of a transendoscopic miniature ultrasonic probe (USP) in the diagnosis of esophageal diseases.

PATIENTS AND METHODS

Endoscopic ultrasonography was performed by means of USP in 53 patients with esophageal diseases, including 16 with esophageal leiomyoma, 14 with esophageal carcinoma, seven with achalasia, seven with reflux esophagitis, six with esophageal polyps and three with esophageal varices.

RESULTS

USP clearly showed all 16 esophageal leiomyomas, whereas, conventional EUS could not show five small leiomyomas less than 1.0 x 1.0 cm in size. The appearance of esophageal leiomyoma was that of a hypoechoic mass with a homogeneous inner echogram arising from the fourth hypoechoic layer. All 14 patients with esophageal carcinoma underwent full endosonographic T and N staging with USP. In two cases passage of the malignant stenosis proved to be impossible using conventional EUS. The accuracy of USP on T staging and N staging was 80% and 30%, respectively. In the seven achalasia patients USP demonstrated a seven-layer structure of the esophageal wall, with thickening of the third and fifth layers. In the seven patients with reflux esophagitis no difference was found for the ultrasonic image between that with and that without Barrett's epithelium. All of the esophageal polyps were showed by USP as hypoechoic homogeneous lesion with indistinct margins. After endoscopic sclerotherapy the ultrasonographic feature of esophageal varices changed from submucosal multiple anechoic areas to high echoic areas.

CONCLUSION

With refinement, the transendoscopic miniature ultrasonic probe will play an increasing role in the diagnosis of esophageal disease.

AtMRP2, an Arabidopsis ATP binding cassette transporter able to transport glutathione S-conjugates and chlorophyll catabolites: functional comparisons with Atmrp1

Three ATP binding cassette (ABC) transporter-like activities directed toward large amphipathic organic anions have recently been identified on the vacuolar membrane of plant cells. These are the Mg-ATP-energized, vanadate-inhibitable vacuolar accumulation of glutathione S-conjugates (GS conjugates), chlorophyll catabolites, and bile acids, respectively. Although each of these activities previously had been assigned to distinct pumps in native plant membranes, we describe here the molecular cloning, physical mapping, and heterologous expression of a gene, AtMRP2, from Arabidopsis thaliana that encodes a multispecific ABC transporter competent in the transport of both GS conjugates and chlorophyll catabolites. Unlike its isoform, AtMRP1, which transports the model Brassica napus chlorophyll catabolite transporter substrate Bn-NCC-1 at low efficiency, heterologously expressed AtMRP2 has the facility for simultaneous high-efficiency parallel transport of GS conjugates and Bn-NCC-1. The properties of AtMRP2 therefore establish a basis for the manipulation of two previously identified plant ABC transporter activities and provide an explanation for how the comparable transporter in native plant membranes would be systematically mistaken for two distinct transporters. These findings are discussed with respect to the functional organization of AtMRP2, the inability of AtMRP2 and AtMRP1 to transport the model bile acid transporter substrate taurocholate (despite the pronounced sensitivity of both to direct inhibition by this agent), the differential patterns of expression of their genes in the intact plant, and the high capacity of AtMRP2 for the transport of glutathionated herbicides and anthocyanins.

AtMRP1 gene of Arabidopsis encodes a glutathione S-conjugate pump: isolation and functional definition of a plant ATP-binding cassette transporter gene

Because plants produce cytotoxic compounds to which they, themselves, are susceptible and are exposed to exogenous toxins (microbial products, allelochemicals, and agrochemicals), cell survival is contingent on mechanisms for detoxifying these agents. One detoxification mechanism is the glutathione S-transferase-catalyzed glutathionation of the toxin, or an activated derivative, and transport of the conjugate out of the cytosol. We show here that a transporter responsible for the removal of glutathione S-conjugates from the cytosol, a specific Mg2+-ATPase, is encoded by the AtMRP1 gene of Arabidopsis thaliana. The sequence of AtMRP1 and the transport capabilities of membranes prepared from yeast cells transformed with plasmid-borne AtMRP1 demonstrate that this gene encodes an ATP-binding cassette transporter competent in the transport of glutathione S-conjugates of xenobiotics and endogenous substances, including herbicides and anthocyanins.

Vacuolar uptake of the phytoalexin medicarpin by the glutathione conjugate pump

We have studied the uptake of [3H]-medicarpin and its glutathione conjugate(s) into vacuolar membrane vesicles from etiolated hypocotyls of mung bean (Vigna radiata). Unconjugated medicarpin is taken up at a low rate in the presence or absence of MgATP. However, [3H]-medicarpin-glutathione conjugate(s), prepared by incubation of medicarpin with a total maize glutathione S-transferase preparation, is taken up more than four-fold faster than medicarpin in the presence of MgATP, and this uptake is MgATP-dependent. Uptake of medicarpin-glutathione was not significantly inhibited by the ionophore gramicidin-D, but was strongly inhibited by vanadate and the alternative transport substrate S-(2,4-dinitrophenyl) glutathione. Our results demonstrate, in a model system, the potential utilization of the high affinity, high capacity, uncoupler-insensitive glutathione conjugate pump for the vacuolar transport of an isoflavonoid phytoalexin.

The GS-X pump in plant, yeast, and animal cells: structure, function, and gene expression

This review addresses the recent molecular identification of several members of the glutathione S-conjugate (GS-X) pump family, a new class of ATP-binding cassette (ABC) transporters responsible for the elimination and/or sequestration of pharmacologically and agronomically important compounds in mammalian, yeast and plant cells. The molecular structure and function of GS-X pumps encoded by MRP, cMOAT, YCF1, and AtMRP genes, have been conserved throughout molecular evolution. The physiologic function of GS-X pumps is closely related with cellular detoxification, oxidative stress, inflammation, and cancer drug resistance. Coordinated expression of GS-X pump genes, e.g., MRP1 and YCF1, and gamma-glutamylcystaine synthetase, a rate-limiting enzyme of cellular glutathione (GSH) biosynthesis, has been frequently observed.

Albumin transfer across the choroid plexus of South American opossum (Monodelphis domestica)

1. Blood-cerebrospinal fluid (CSF) transfer of various exogenous albumins has been investigated in developing Monodelphis domestica (South American grey short-tailed opossum) and compared with the steady-state CSF: plasma ratios for endogenous (Monodelphis) albumin. Ratios for Monodelphis albumin and human albumin were similar and were the highest at postnatal day 5 (P5) (48.2 +/- 4.4 and 40.6 +/- 4.5%, respectively). The ratio for bovine albumin was similar to the steady-state ratio for Monodelphis albumin at P7-8 but became consistently lower than the Monodelphis albumin ratio at all other ages until P32-36 when all albumins tested attained a similar low ratio. The CSF:plasma ratio of chemically modified (succinylated) bovine albumin was always significantly lower than that of other albumins, except at the oldest age examined (P32-36). 2. Immunocytochemistry showed that within the brain, albumin was confined to the lumen and endothelial cells of blood vessels. In the choroid plexus only a small proportion (0.2-1.7% of the total cell number) of epithelial cells was positive for albumin, both endogenous and exogenous, at all ages studied (except the 3rd ventricle where cells were only positive from P8). The CSF was strongly positive for all albumins. The peak proportion of positive cells and of albumin concentrations in CSF occurred at P8. These findings suggest that the primary route for penetration of albumin into CSF is directly across the choroid plexus rather than via the brain. 3. Double-labelling immunocytochemistry revealed that the same epithelial cells contained both endogenous (Monodelphis) and exogenous (human) albumin. In contrast, for succinylated albumin, at P7 only about 35% (lateral ventricle) and 50% (4th ventricle) of Monodelphis albumin-positive cells were also positive for succinylated albumin, but by P30 this proportion increased to 90% at both sites. 4. Thus the developing choroid plexus distinguishes between different albumins. Chemical modification of albumin (succinylation) disrupts this mechanism. It is proposed that in older animals (P32-36) all of the albumin in the CSF is derived from plasma by diffusion (as in adult animals). At earlier stages of development, a proportion of the albumin in CSF also appears to be transferred from the plasma by diffusion with an additional component transferred by a mechanism that can distinguish between different species of albumin. The main route of entry of albumin to CSF seems likely to be via the choroid plexus epithelial cells.

Transthyretin distribution in the developing choroid plexus of the South American opossum (Monodelphis domestica)

The distributions of transthyretin and albumin in the choroid plexus during brain development have been compared. The South American opossum was chosen because the young are born around the time of choroid plexus formation. Previous work showed that in the adult opossum, transthyretin is expressed in the choroid plexus cells. However, systematic studies of transthyretin in the choroid plexus during development have not been carried out before. Transthyretin was present in 90-95% of the choroidal cells form birth to adulthood. In most cells, transthyretin immunoreactivity was concentrated in the apical region of the cytoplasm. Double labelling of choroid plexus sections with antibodies to albumin and transthyretin showed that 1-2% of cells were positive for both proteins. These findings suggest that from the very earliest stage of choroid plexus formation most epithelial cells both synthesize and contain transthyretin, and a few of these transthyretin-synthesizing cells also contain albumin that is probably being transferred form blood to the cerebrospinal fluid.

A new pathway for vacuolar cadmium sequestration in Saccharomyces cerevisiae: YCF1-catalyzed transport of bis(glutathionato)cadmium

The yeast cadmium factor (YCF1) gene encodes an MgATP-energized glutathione S-conjugate transporter responsible for the vacuolar sequestration of organic compounds after their S-conjugation with glutathione. However, while YCF1 was originally isolated according to its ability to confer resistance to cadmium salts, neither its mode of interaction with Cd2+ nor the relationship between this process and organic glutathione-conjugate transport are known. Here we show through direct comparisons between vacuolar membrane vesicles purified from Saccharomyces cerevisiae strain DTY167, harboring a deletion of the YCF1 gene, and the isogenic wild-type strain DTY165 that YCF1 mediates the MgATP-energized vacuolar accumulation of Cd-glutathione complexes. The substrate requirements, kinetics and Cd2+/glutathione stoichiometry of cadmium uptake and the molecular weight of the transport-active complex demonstrate that YCF1 selectively catalyzes the transport of bis(glutathionato)cadmium (Cd x +GS2). On the basis of these results--the Cd2+ hypersensitivity of DTY167, versus DTY165, cells, the inducibility of YCF1-mediated transport, and the rapidity and spontaneity of Cd-GS2 formation--this new pathway is concluded to contribute substantially to Cd2+ detoxification.

The yeast cadmium factor protein (YCF1) is a vacuolar glutathione S-conjugate pump

The yeast cadmium factor gene (YCF1) from Saccharomyces cerevisiae, which was isolated according to its ability to confer cadmium resistance, encodes a 1,515 amino acid ATP-binding cassette (ABC) protein with extensive sequence homology to the human multidrug resistance-associated protein (MRP1) (Szczypka, M., Wemmie, J. A., Moye-Rowley, W. S., and Thiele, D. J. (1994) J. Biol. Chem. 269, 22853-22857). Direct comparisons between S. cerevisiae strain DTY167, harboring a deletion of the YCF1 gene, and the isogenic wild type strain, DTY165, demonstrate that YCF1 is required for increased resistance to the toxic effects of the exogenous glutathione S-conjugate precursor, 1-chloro-2,4-di-nitrobenzene, as well as cadmium. Whereas membrane vesicles isolated from DTY165 cells contain two major pathways for transport of the model compound S-(2,4-dinitrophenyl)glutathione (DNP-GS), an MgATP-dependent, uncoupler-insensitive pathway and an electrically driven pathway, the corresponding membrane fraction from DTY167 cells is more than 90% impaired for MgATP-dependent, uncoupler-insensitive DNP-GS transport. Of the two DNP-GS transport pathways identified, only the MgATP-dependent, uncoupler-insensive pathway is subject to inhibition by glutathione disulfide, vanadate, verapamil, and vinblastine. The capacity for MgATP-dependent, uncoupler-insensitive conjugate transport in vitro strictly copurifies with the acuolar membrane fraction. Intact DTY165 cells, but not DTY167 cells, mediate vacuolar accumulation of the quorescent glutathione-conjugate, monochlorobimane-GS. Introduction of plasmid borne, epitope-tagged gene encoding functional YCF1 into DTY167 cells alleviates the 1-chloro-2,4-dinitrobenzene-hypersensitive phenotype concomitant with restoration of the capacity of vacuolar membrane vesicles isolated from these cells for MgATP-dependent, uncoupler-insensitive DNP-GS transport. On the basis of these findings, the YCF1 gene of S. cerevisiae is inferred to encode an MgATP-energized, uncoupler-insensitive vacuolar glutathione S-conjugate transporter. The energy requirements, kinetics, substrate specificity, and inhibitor profile of YCF1-mediated transport demonstrate that the vacuolar glutathione conjugate pump of yeast bears a strong mechanistic resemblance to the MRP1-encoded transporter of mammalian cells and the cognate, but as yet molecularly undefined, function of plant cells.

Do vasoactive intestinal peptide (VIP)- and nitric oxide synthase-immunoreactive terminals synapse exclusively with VIP cell bodies in the submucous plexus of the guinea-pig ileum?

In the submucous plexus of the guinea-pig ileum, previous light-microscopic studies have revealed that vasoactive intestinal peptide (VIP)-immunoreactive and nitric oxide synthase (NOS)-immunoreactive terminals are found predominantly in association with VIP-immunoreactive nerve cell bodies. In this study, double-label immunohistochemistry at the light-microscopic level demonstrated co-localization of NOS-immunoreactivity and VIP-immunoreactivity in axon terminals in submucous ganglia. About 90% of nerve fibres with NOS-immunoreactivity or VIP-immunoreactivity were immunoreactive for both antigens; only about 10% of labelled varicosities contained only NOS-immunoreactivity or VIP-immunoreactivity. The VIP/NOS varicosities were more often seen in the central parts of the ganglia, close to the VIP-immunoreactive cell bodies. Ultrastructural immunocytochemistry with antibodies to VIP was used to determine if NOS/VIP terminals synapse exclusively with VIP-immunoreactive nerve cell bodies. We examined the targets of VIP-immunoreactive boutons in two submucous ganglia from different animals. Serial ultrathin sections were taken through the ganglia after they had been processed for VIP immunocytochemistry. For each cell body, the number of VIP inputs (synapses and close contacts) was determined. The number of VIP-immunoreactive synapses received by the cell bodies of submucous neurons varied from 0-4 and the number of VIP-immunoreactive close contacts varied from 3-10. There was no significant difference between VIP-immunoreactive nerve cell bodies and non-VIP nerve cell bodies in the number of VIP-immunoreactive synapses and close contacts they received. Thus, the implication from light microscopy that NOS/VIP terminals end predominantly on VIP nerve cells was not vindicated by electron microscopy.

Compact, magneto-optic Q-switched, neodymium-doped bismuth germinate crystal (Nd:BGO) laser pumped by a laser diode

The magneto-optic Q-switched operation of a neodymium-doped bismuth germinate crystal (Nd:BGO) laser that is end pumped by a cw 500-mW laser diode is reported. The crystal is a new host for Nd lasers. Here it acts as a magneto-optic modulator as well as a laser medium. A pulse energy of 2 µJ with a FWHM of 100 ns has been obtained. The device operates at a repetition rate of 1 kHz, and the fluctuation of the shot-to-shot intensity is less than ±1%.

Affinity purification of sucrose binding proteins from the plant plasma membrane

Purified plasma membranes from sugar beet leaves were solubilized by 1% 3-((3-cholamidopropyl)dimethylammonio)-1-propanesulfonate and loaded on a sepharose 6 B column substituted with sucrose. Elution with sucrose at pH 5.2 yielded a peak that represented 0.2% of the loaded protein. This peak did not appear when the samples were pretreated with either 0.5 mM N-ethylmaleimide (NEM) or 0.5 mM para-chloromercuribenzenesulfonic acid. It was also absent when palatinose, a sucrose analogue not recognized by the sucrose transporter, was used as the affinity ligand. The peak specifically eluted by sucrose from the sucrose-Sepharose column exhibited sucrose transport activity after reconstitution into proteoliposomes. This peak was further fractionated by ion-exchange chromatography on a Mono-Q column, and the different fractions obtained were differentially labeled by [3H]NEM in the presence of sugars recognized (sucrose, maltose) or not recognized (palatinose) by the sucrose transporter. The data allowed to identify two fractions that were enriched with two polypeptides (56 and 41 kDa) differentially labeled by NEM in the presence of sucrose.

[Distribution of rabies antigen in human tongue and salivary gland]

The distribution of rabies virus antigen (RVAg) in human tongue and salivary glands from three cases was studied with ABC immunohistochemical method. Of the 5 tissue blocks from 2 tongues, large amounts of RVAg were found in 4 tissue blocks, located in the serous glands, terminal nerves, some striated muscle fibers and some covering epithelium including taste cells of circumvallate papillae. Only small amounts of RVAg were present in 4 of the 9 salivary gland blocks, either within the acini or in nerves. These results differ from that reported previously in dog, fox and skunk salivary glands, which contained abundant RVAg. The amount of RVAg in human tongue is apparently greater than that in the salivary glands. It is probable that the serous glands of the human tongue are sites of predilection for RVAg and may serve as a source of infection.

Nitric oxide synthase in the enteric nervous system of the guinea-pig: a quantitative description

The distribution and abundance of nitric oxide synthase (NOS)-containing neurons and their terminals in the gastrointestinal tract of the guinea-pig were examined in detail using NADPH diaphorase histochemistry and NOS immunohistochemistry. NOS-containing cell bodies were found in the myenteric plexus throughout the gastrointestinal tract and in the submucous plexus of the stomach, colon and rectum. NOS-containing neurons comprised between 12% (in the duodenum) and 54% (in the esophagus) of total myenteric neurons. In the ileum, NOS neurons represented 19% of total myenteric neurons. Most of the NOS neurons throughout the gastrointestinal tract possessed lamellar dendrites and a single axon. NOS-containing terminals were abundant in the circular muscle, including that of the sphincters, but were rare in the longitudinal muscle, except for the taeniae of the caecum. The muscularis mucosae of the esophagus, stomach, colon and rectum received a medium to dense innervation by NOS terminals. Within myenteric ganglia, NOS-containing terminals were extremely sparse in the esophagus, stomach and duodenum, common in the ileum and distal colon and extremely dense in the proximal colon and rectum. The submucous plexus in the ileum and large intestine contained a sparse plexus of NOS-containing terminals. NOS terminals were not observed in the mucosa of any region. We conclude that throughout the gastrointestinal tract of the guinea-pig, NOS neurons are inhibitory motor neurons to the circular muscle; in the ileum and large intestine, NOS neurons may also function as interneurons.

Nitric oxide synthase in neurons of the gastrointestinal tract of an avian species, Coturnix coturnix

The distribution of reduced nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase staining and its colocalisation with nitric oxide synthase immunoreactivity was examined in neurons of the quail gastrointestinal tract. Immunoreactivity and enzyme activity were found in identical populations of neurons. Nitric oxide synthase activity was present in 30-40% of myenteric nerve cells in each region. Numerous reactive cells were also in the submucous plexus and many positive nerve fibres innervated the muscle. In the small intestine, some of the fibres innervating the circular muscle formed a deep muscular plexus and in the large intestine there was a submuscular plexus. Nerve fibres formed baskets around nerve cells of myenteric and submucous ganglia. Intramural arterioles were innervated, most prominently in the oesophagus and stomach. Very few fibres innervated the mucosa, except for some oesophageal glands and the core of villi in the cloaca. It is concluded that nitric oxide is probably involved in transmission to muscle of the avian intestine, as it is in mammals, and that it is probably also produced at neuroneuronal and neurovascular junctions.

Projections of nitric oxide synthase- and peptide-containing neurons in the small and large intestines of the toad (Bufo marinus)

The projections of galanin (GAL)- and vasoactive intestinal peptide (VIP)-immunoreactive (IR) and nitric oxide synthase (NOS)-containing neurons in the small and large intestines of the amphibian Bufo marinus were investigated by their reactions to surgical interruption (myotomy). In the small intestine, myotomy caused accumulation of GAL- and VIP-IR and of NADPH diaphorase reaction product (revealing NOS) in cut axons on the oral side of the operation site. On the anal side there was loss of GAL-IR axons from the circular muscle and myenteric plexus and long, anally directed processes could be traced from GAL-IR nerve cell bodies. There was no significant loss of VIP-IR or NADPH diaphorase from nerve fibres in the myenteric plexus or circular muscle layer, although anally-directed axons could be traced from nerve cell bodies on the anal side of the operation sites. In the large intestine, myotomy caused accumulation of VIP-IR and of NADPH diaphorase reaction product in cut axons on the oral side of the operation site. Anal to the cut, although there was no significant loss of these fibres from the muscle or myenteric plexus, anally directed axons could be traced from nerve cell bodies. GAL-IR fibres in the large intestine are of two types: a few contain GAL-IR alone and are thought to arise from enteric neurons; many contain both GAL- and SOM-IR and are thought to arise from nerve cell bodies in the hindgut. Myotomy caused an accumulation of GAL/SOM-IR material in fibres on the anal side of the cut and a substantial decrease in the number of fibres on the oral side. There was no detectable effect of myotomy on the GAL-IR fibres, although an abnormally high density of GAL-IR nerve cell bodies was found oral to the cut. These results indicate that VIP-IR and NOS-containing enteric neurons project in an oral to anal direction in the toad small and large intestines. Some of the neurons have short anal projections to the circular muscle. GAL-IR enteric neurons have similar projections in the small intestine, but their projections could not be determined in the large intestine. GAL/SOM-IR axons in the large intestine project from anal to oral. Myotomy in the large intestine appears to induce an increased or de novo expression of GAL-IR in enteric neurons oral to the cut.

[Pharmacokinetics of moracizine and moracizine sulfoxide in healthy volunteers]

The pharmacokinetics of moracizine (Mor) and moracizine sulfoxide (Mor-SO) determined by reversed phase HPLC was reported. The data in 6 volunteers after a single oral dose (600 mg) showed an one-compartment open model. The peak concentration in plasma (2.1 +/- 0.4 micrograms.ml-1) of Mor reached within 1-2 h. The Mor-SO concentration in plasma was much lower (0.19 +/- 0.06 micrograms.ml-1) than that of Mor, but its elimination T1/2 (2.3 +/- 1.0 h) was similar to that of Mor (1.5 +/- 1.0 h). The recoveries of Mor, Mor-SO, moracizine sulfone (Mor-SO2) in urine within 48 h were 0.07%, 0.25%, and 0.06% of the total dose, respectively. The Mor and Mor-SO concentration ranges in plasma for 9 arrhythmic patients after 2-wk therapeutic trial were 0.09 +/- 0.07 to 0.9 +/- 0.5 microgram.ml-1 and 0.040 +/- 0.023 to 0.15 +/- 0.06 micrograms.ml-1, respectively. These results suggested that cumulative doses would not result in accumulation of the drug and the anti-arrhythmic effect of Mor-SO might not be realized.

Relationships between nitric oxide synthase, vasoactive intestinal peptide and substance P immunoreactivities in neurons of the amphibian intestine

Nitric oxide synthase (NOS)-containing neurons (localized using NADPH diaphorase histochemistry or NOS immunoreactivity) and vasoactive intestinal peptide-immunoreactive (VIP-IR) neurons were found in the myenteric plexus of the gastrointestinal tract of the amphibian, Bufo marinus. Only limited co-localization of the two substances was observed in nerve cell bodies, about 11% of the NOS-containing neurons were also labelled by VIP-IR and about 37% of VIP-IR nerve cell bodies contained NOS. The relationship between VIP, NOS and SP-IR in nerve fibres in the circular muscle was examined. There was partial co-localization of VIP and NOS, but no co-localization of NOS or VIP with substance P. Of fibres that were immunoreactive for VIP or NOS, fewer than 10% contained VIP alone.

Nitric oxide synthase in the enteric nervous system of the rainbow trout, Salmo gairdneri

The distribution of nitric oxide synthase (NOS) was determined in the gastrointestinal tract of the rainbow trout, Salmo gairdneri. NOS immunoreactivity and the NADPH diaphorase histochemical reaction were co-localized in nerve cells in the myenteric ganglia. However, only about 60% of NADPH diaphorase-stained nerve cells in the vagus nerve trunks were immunoreactive for NOS. Reactive myenteric nerve cells were found throughout the gastrointestinal tract, comprising about 10-15% of all nerve cells. Reactive nerve cells and fibres appeared in the myenteric ganglia and nerve trunks. The circular muscle was innervated by reactive nerve fibres throughout the gastrointestinal tract. Some NOS-containing cell bodies were also in this layer. The submucous plexus contained reactive nerve fibres in each region of the gut; in the large intestine a few reactive nerve cell bodies were also seen in this plexus. The muscle in the mucosal folds of the large intestine was densely innervated. The observations suggest that nitric oxide is an enteric transmitter in teleost fish, as it is in mammals.

20-item neonatal behavioral neurological assessment used in predicting prognosis of asphyxiated newborn

From January 1989 to June 1990, 13 institutions in our country studied jointly the application of a 20-item neonatal behavioral neurological assessment (NBNA) in asphyxiated babies. Of 145 cases, 125 were followed up to 1-2 years of age. The results showed that in predicting prognosis, the sensitivity and specificity of NBNA score at 7 days after birth were 88.9% and 82.6% and 12-14 days, 84.6% and 97.4% respectively. Its value in predicting prognosis is superior to Sarnat degree, cranial CT and B ultrasound. This method is practical, economical and reliable. It is worth popularizing.

Nitric oxide synthase immunoactivity and NADPH diaphorase enzyme activity in neurons of the gastrointestinal tract of the toad, Bufo marinus

The presence of nitric oxide synthase (NOS) was demonstrated immunohistochemically, and NADPH diaphorase was demonstrated by enzyme histochemistry in neurons throughout the gastrointestinal tract of the anuran amphibian, Bufo marinus. Successive staining showed that NOS immunoreactivity and NADPH diaphorase activity occurred in precisely the same subgroup of enteric neurons. Subsequent detailed studies of the distribution of these neurons were made using NADPH diaphorase histochemistry. Numerous reactive nerve cell bodies and fibres were found in the myenteric plexus from the esophagus to the cloaca. A dense innervation of the longitudinal and circular muscle layers occurred throughout the gastrointestinal tract. The lamina muscularis mucosae was only prominent in the stomach, where it was sparsely innervated. Reactive nerve cell bodies were common in the submucosa of the large intestine, less common in the small intestine and extremely rare in the stomach and esophagus. Reactive fibres contributed to subepithelial plexuses in the esophagus, colon, rectum and cloaca. It is concluded that NOS/NADPH diaphorase is conserved amongst vertebrate classes and that NO is a likely neurotransmitter in the toad gastrointestinal tract.

The sucrose carrier of the plant plasmalemma. III. Partial purification and reconstitution of active sucrose transport in liposomes

The proteins from plasma membranes from sugar beet leaves were solubilized by 1% CHAPS and separated by size exclusion chromatography and by ion-exchange chromatography. The fractions enriched in sucrose transporter were monitored in three ways: differential labeling, ELISA, and reconstitution in proteoliposomes. When the plasma membranes were differentially labeled by N-ethylamaleimide in the presence of sucrose, a major peak of differential labeling was found at 120 kDa upon gel filtration. When this peak was recovered, denaturated by sodium dodecyl sulfate and reinjected on the gel filtration column, it yielded a peak of differential labeling at 42 kDa. When unlabeled membranes were used, the fractions eluted from the column were monitored by ELISA for their ability to recognize a serum directed against a 42 kDa previously identified as a putative sucrose carrier. The results paralleled those obtained by differential labeling, i.e. a major ELISA-reactive peak was found at 120 kDa upon gel filtration, and this peak yielded a peak most reactive at 40 kDa after denaturation. The 120 kDa peak prepared from unlabeled membranes was further separated on a Mono-Q column. The fractions were monitored by ELISA as described above, and reconstituted into proteoliposomes using asolectin. Active transport of sucrose, but not of valine could be observed with the reconstituted 120 kDa fraction. When the eluates from the Mono-Q column were reconstituted, the fractions exhibiting highest transport activity were enriched with a 42 kDa band. The data provide the first report concerning reconstitution of sucrose transport activity and confirm the involvement of a 42 kDa polypeptide in sucrose transport.

Influence of outer membrane mutations on susceptibility of Escherichia coli to the dibasic macrolide azithromycin

Azithromycin differs chemically from erythromycin by having an extra positive charge created by the presence of a methyl-substituted nitrogen in the 15-membered macrolide ring. This results in substantially increased potency against Gram-negative bacteria. Therefore, the possibility was considered that azithromycin was taken across the outer membrane of Escherichia coli by the self-promoted uptake route, which is utilized by other cationic antibiotics including polymyxins and aminoglycosides. Azithromycin, like polymyxin B and gentamicin, demonstrated equal activity against porin-sufficient and porin-deficient E. coli strains but its MIC was increased eight-fold by magnesium supplementation. Nevertheless, an outer membrane-altered mutant DC2 was eight-fold more susceptible than its parent strain UB1005 to azithromycin, indicating that the outer membrane was a permeability barrier to this macrolide. A mutant SC9252 which had an alteration in the self-promoted uptake of polymyxin and gentamicin, was more resistant to azithromycin, polymyxin and gentamicin compared to its parent SC9251. Further azithromycin, like polymyxin B and gentamicin, was capable of weakly permeabilizing cells to the hydrophobic fluorophor 1-N-phenyl-naphthylamine, a process antagonized by Mg2+. The monobasic macrolide erythromycin on the other hand was less affected by the SC9252 mutation, less effectively antagonized by Mg2+, and was a far less effective permeabilizer than dibasic azithromycin. These data are consistent with the hypothesis that the improved efficacy of azithromycin compared to erythromycin against E. coli reflects its better access to the self-promoted uptake pathway due to its additional positive charge.

Serotyping of Canadian isolates of Treponema hyodysenteriae and description of two new serotypes

A total of 30 isolates of Treponema hyodysenteriae collected in the Saint-Hyacinthe (Quebec, Canada) area were serotyped by agar gel double immunodiffusion by using extracted lipopolysaccharide and hyperimmune rabbit antisera. Only 17% (5 of 30) of the isolates were typed with antisera specific for each of the seven known serotypes of T. hyodysenteriae. Antisera raised against 11 untypeable local isolates were then produced and tested against each lipopolysaccharide extract. Results showed two serologically distinct groups among 21 of the 25 untypeable isolates. The isolates in each group shared identical antigens. No detectable reactions could be observed between antisera raised against these 11 isolates and the antigens extracted from 7 reference serotype strains. On the basis of these results, two new serotypes of T. hyodysenteriae, serotypes 8 and 9, are proposed. We also propose isolate FM 88-90 as the reference strain for serotype 8 and isolate FMV 89-3323 as the reference strain for serotype 9. These two new serotypes, which represented 70% of the isolates tested, seem to be the major serotypes found in the province of Quebec.

Twenty-item behavioral neurological assessment for normal newborns in 12 cities of China

Based on the method of Brazelton and Amiel-Tison for behavioral neurological measurement in the newborn and our own experience, we formulated a 20-item neonatal behavioral neurological assessment (NBNA). For setting up a practical method and a normal range of its scores in China, we examined 714 normal newborns (male 369, female 345), with NBNA at the age of 2-3, 12-14, 26-28 days for a total of 2,142 times, in 12 provinces of China from May to October 1988. NBNA contains 5 clusters: behavior (6 items); passive tone (4 items); active tone (4 items); primary reflexes (3 items); and general assessment (3 items). Each item has 3 scales (0,1,2). Twenty items have a maximum of 40 scores. Among the 2,142 times examined, 90.4% of the 714 newborns had 39-40 scores, 97% greater than 37 and none below 35. Measurements of the first, second and third time revealed that the total scores increased with age. The difference was statistically significant. The abilities of auditory and visual orientations and active neck tone improved obviously with age. NBNA shows distinct stability and reliability. The score is not influenced by geographic location; the scoring system is simple and the manipulation takes only ten minutes.

Reconstitution of active sucrose transport in plant proteoliposomes

The proteins of purified plasma membranes from sugar beet (Beta vulgaris L.) leaf were solubilized and separated on a size exclusion column. The fractions eluted from the column were monitored by ELISA with antibodies directed to a putative sucrose carrier protein. The peak most reactive in ELISA was approximately 120 kDa, and yielded a 40 kDa peak after denaturation by SDS. The 120-kDa peak was recovered and used for reconstitution experiments with asolectin. Upon imposition of an artificial pH gradient and electrical gradient, the obtained proteoliposomes exhibited active transport of sucrose, but not of valine. The active transport of sucrose was inhibited by N-ethylmaleimide and HgCl2.

Interaction of aminoglycosides with the outer membranes and purified lipopolysaccharide and OmpF porin of Escherichia coli

The mechanism of uptake of aminoglycosides across the outer membrane of Escherichia coli was reevaluated. Porin-deficient mutants showed no alteration in gentamicin or kanamycin susceptibility. Furthermore, the influence of kanamycin on intrinsic tryptophan fluorescence of porin OmpF (Y. Kobayashi, and T. Nakae, Eur. J. Biochem. 151:231-236, 1985) was shown to be strongly influenced by protein concentration and EDTA. This led to the hypothesis that aminoglycoside-mediated increases and decreases in intrinsic tryptophan fluorescence were due to aggregation-disaggregation of OmpF mediated by interaction at a divalent cation binding site on OmpF. Gentamicin, kanamycin, and polymyxin B increased E. coli outer membrane permeability to the hydrophobic fluorescent compound 1-N-phenyl-naphthylamine (NPN) and the peptidoglycan-degrading enzyme lysozyme. Addition of Mg2+ blocked these permeabilizing activities. Furthermore, gentamicin and polymyxin B bound to Mg(2+)-binding sites on E. coli lipopolysaccharide, as determined in dansyl polymyxin displacement experiments. A polymyxin-resistant, lipopolysaccharide-altered pmr mutant of E. coli had a fourfold-lower MIC of gentamicin and kanamycin and was more poorly permeabilized to 1-N-phenylnaphthylamine than was its parent strain. These data were consistent with uptake of aminoglycosides across the E. coli outer membrane by the self-promoted uptake mechanism.

[Analysis of DNA content of cells from liver cell dysplasia and hepatocellular carcinoma]

Nuclear DNA content of malignant cells was measured by OPTON type III microspectrophotometry in 19 cases of hepatocellular carcinoma (HCC), as well as cells from the paraneoplastic tissue. The mean DNA value increased significantly from non liver cell dysplasia (LCD), LCD to HCC (P less than 0.05-0.01). In histograms, non-LCD hepatocyte showed a single-peak type located at 2C. HCC showed lower multi-peaks which migrated to 4C and spread widely with more aneuploid (greater than 5C) cells. The histograms of LCD were between non-LCD and HCC, and there were also some aneuploids in LCD. These results suggest that LCD is a group of proliferating cells, and those with relatively high ratio of aneuploid cells might be premalignant.

Effect of Astragulas membranaceus on natural killer cell activity and induction of alpha- and gamma-interferon in patients with Coxsackie B viral myocarditis

The patients suffering from Coxsackie B viral myocarditis with depressed natural killer (NK) activity were treated with Astragulas membranaceus (AM) intramuscularly for 3-4 months. After the treatment, the NK activity was increased significantly from 11.5 +/- 11.9% before therapy to 44.9 +/- 15.0%. Another 6 patients of Coxsackie B viral myocarditis with depressed NK activity were treated with conventional therapy. The NK activity remained unchanged in 12.9 +/- 6%. The general condition and symptoms improved in all patients with AM therapy, while the titers of neutralizing antibody remained at the same level. Two days after AM treatment, the mean titers of alpha- and gamma-interferon (IFN) markedly increased in comparison with those before therapy and 3 weeks after AM therapy in 16 patients with Coxsackie B viral myocarditis, with left ventricular ejection fraction (LVEF) less than 65% and/or weak ventricular wall motion assayed by radionuclide angiocardiography. Whereas, in 12 patients treated with conventional therapy, there was no statistical difference among the results before and 2 days and 3 weeks after treatment. The results indicate that AM could partly regulate the lost of control of cellular immunity in patients with viral myocarditis.

[Changes of mucosal blood flow in the healing process of peptic ulcer]

Changes of gastroduodenal mucosal blood flow (GDMBF) in the healing process of 79 cases of gastric ulcer and 118 cases of duodenal ulcer were investigated by Laser Doppler Flowmetry during endoscopy. 108 cases with no gastroduodenal lesions were used as controls. In the controls, the mucosal blood flow was greater at the corpus than at the antrum and the angle, and it was smaller at the lesser curvature than at the greater curvature. The mucosal blood flow at the antrum and the angle of the lesser curvature was the smallest. The mucosal blood flow at the anterior wall of the duodenal bulbus was lower than at the lesser curvature and the posterior wall. In patients with active gastric ulcer, GMBF were decreased significantly. The mucosal blood flow at the ulcer center and ulcer margin was lower in the active stage and it was increased markedly in the healing stage, while no marked change was observed in peripheral mucosal blood flow during the different stages.