Expression of transforming growth factor-alpha and epidermal growth factor receptor in gastrointestinal stromal tumours

Activation of epidermal growth factor receptor (EGFR) is associated with cell growth and transformation. Both transforming growth factor-alpha (TGF-alpha) and epidermal growth factor bind to and activate EGFR. We studied the expression of TGF-alpha and two EGFRs (HER-1 and HER-2) in gastrointestinal stromal tumours (GISTs) of the stomach (n = 9) and small intestine (n = 6) using standard immunostaining techniques in paraffin-embedded sections. Most GISTs expressed TGF-alpha, and a few expressed HER-1. All HER-1-positive tumours expressed TGF-alpha. These results suggest that a TGF-alpha/EGFR autocrine loop is present in GIST and that TGF-alpha promotes proliferation of GIST tumour cells through its interaction with HER-1 in at least some GISTs. This is the first description of an autocrine loop in GIST. In contrast, HER-2 is not expressed in any GIST.

Directional guidance of neuronal migration in the olfactory system by the protein Slit

Although cell migration is crucial for neural development, molecular mechanisms guiding neuronal migration have remained unclear. Here we report that the secreted protein Slit repels neuronal precursors migrating from the anterior subventricular zone in the telencephalon to the olfactory bulb. Our results provide a direct demonstration of a molecular cue whose concentration gradient guides the direction of migrating neurons. They also support a common guidance mechanism for axon projection and neuronal migration and suggest that Slit may provide a molecular tool with potential therapeutic applications in controlling and directing cell migration.

Bacterial photoreceptor with similarity to photoactive yellow protein and plant phytochromes

A phytochrome-like protein called Ppr was discovered in the purple photosynthetic bacterium Rhodospirillum centenum. Ppr has a photoactive yellow protein (PYP) amino-terminal domain, a central domain with similarity to phytochrome, and a carboxyl-terminal histidine kinase domain. Reconstitution experiments demonstrate that Ppr covalently attaches the blue light-absorbing chromophore p-hydroxycinnamic acid and that it has a photocycle that is spectrally similar to, but kinetically slower than, that of PYP. Ppr also regulates chalcone synthase gene expression in response to blue light with autophosphorylation inhibited in vitro by blue light. Phylogenetic analysis demonstrates that R. centenum Ppr may be ancestral to cyanobacterial and plant phytochromes.

Neuronal and glial DNA fragmentation in Pick's disease

Pick's disease (PD) is characterized by severe neuronal loss and gliosis in a frontotemporal lobar distribution, often associated with Pick bodies and ballooned neurons. Abnormal tau metabolism has been implicated in the pathogenesis of PD; however, the underlying mechanism of neuronal degeneration remains poorly understood. Evidence from other neurodegenerative diseases has suggested that DNA damage and apoptosis may play a major role in cellular degeneration and death. In the present study, an in situ nucleotidyl transferase assay (ISNTA) was used to identify DNA fragmentation in three cases of classical PD with Pick bodies and ballooned neurons, and two PD "variants", one with ballooned neurons only and the other without Pick bodies or ballooned neurons. In all cases large numbers of ISNTA-positive neurons were present in anatomic regions having obvious degenerative changes (neuronal atrophy and loss, gliosis, cytoplasmic inclusions) by conventional histology. There was no clear association between neuronal DNA fragmentation and the presence of structural abnormalities such as Pick bodies or ballooned cytoplasm. ISNTA-positive glia were present in both cortex and subcortical white matter. Morphologic evidence of apoptosis was not detected in either neurons or glial cells. We suggest that DNA fragmentation in PD and probably other neurodegenerative disorders most likely specifies a population of potentially vulnerable cells in which both cell death and repair mechanisms have been activated. It is likely that only a very small number of these vulnerable cells at a given time will proceed to cell death; however, it is uncertain whether this occurs by apoptosis or some other mechanism.

Invariant chain expression in colon neoplasms

Invariant chain (Ii) is a chaperone molecule that inhibits binding of endogenous antigens to class II molecules. High levels of Ii in cancer cells may prevent tumour antigen expression with class II and render the tumour less immunogenic. To correlate the expression of Ii and class II molecules in colon carcinomas with the density of tumour infiltrating lymphocytes (TILs), surgical specimens from a total of 48 patients with well-(WDAC), moderately (MDAC) and poorly differentiated adenocarcinomas (PDAC), adenoma with high-grade dysplasia (AdHGD) and adenomas were immunostained for Ii and class II antigen (HLA-DR). Aggregates of TILs were graded in H&E-stained sections. Normal colon epithelium was negative for Ii and HLA-DR. Invasive carcinomas showed a linear increase in the expression of Ii in the progression from low- to high-grade tumours, while there was no significant difference in HLA-DR expression across the groups. Invasive carcinomas showed a disproportionate increase in Ii over HLA-DR. Frequency of TILs showed inverse correlation with expression of Ii and tumour grade. This is the first demonstration that expression of Ii increases in the progression from low- to high-grade colon neoplasms and is most marked in the poorly differentiated carcinomas. Ii expression by carcinomas is inversely related to the frequency of TILs. The findings suggest that increased Ii renders the tumour less immunogenic and less likely to stimulate a host immune response.

Six triterpenoid saponins from Mmaesa laxiflora

Six new triterpenoid saponins, maelaxins A-F (1-6), were isolated from a n-BuOH extract of the leaves of Maesa laxiflora. They possess 22-O-angeloyl-camelliagenin A, 16-O-acetyl, 22-O-angeloyl-camelliagenin A, or 22-O-(2Z)-hexenoyl-camelliagenin A as the aglycon. The pentasaccharide moiety linked to C-3 of the aglycon consists of D-glucuronic acid, L-rhamnose, D-glucose, and/or D-galactose. Their structures were elucidated by extensive NMR experiments including 1H-1H (COSY, 2D HOHAHA, NOESY) and 1H-13C (HMQC and HMBC) spectroscopy and chemical evidence.

Alteration in enterocyte gene expression may explain structural and functional changes following glutamine supplemented parenteral nutrition

Following extensive bowel resection, the intestinal tract undergoes a variety of adaptive responses to enhance bowel function. The purpose of this study was to determine the effect of glutamine-supplemented parenteral nutrition on mucosal cellularity and gut function. In addition, enterocyte gene expression of two relevant systems was also characterized and related to the structural and functional changes that occurred. Male Wistar rats underwent a 60% small bowel resection and jugular vein catheterization and were randomized into two groups. The control group (n = 10) received a standard intravenous nutritional solution and the study group (n = 10) received a similar solution but enriched with alanylglutamine dipeptide. After 7 days blood was taken for amino acid analysis, and bowel was harvested to determine mucosal morphology and expression of mucosal cell glutaminase and IGF-I mRNA. Mesentery lymphnodes were cultured to determine the presence of bacteria and thus access bacteria translocation. Serum glutamine concentration and mucosal architecture were maintained in the study group compared to the controls. Seventy percent of lymphnodes were cultured positive in control vs. only 20% in the study group (P < 0.05). Jejunal mucosal glutaminase and ileum mucosal IGF-I mRNA increased twofold and threefold respectively compared to control animals. Parenteral nutrition supplemented with alanyl-glutamine dipeptide supports mucosal cellularity and regional immune function in rodents following intestinal resection, These alterations are associated with enhanced enterocyte expression of glutaminase and IGF-I. These changes may facilitate the structural and functional alterations which were observed in the glutamine treated animals.

Frequency and Distribution of DNA fragmentation in Hashimoto's thyroiditis and development of papillary thyroid carcinoma

Downregulation of apoptosis and high expression of bcl-2 play an important role in the development of follicular lymphoma. However, little is known about apoptosis in thyroid disease, particularly with respect to the development of papillary carcinoma from Hashimoto's thyroiditis. To study the early stages of cell death in various types of thyroid disease, surgical specimens from 31 patients including Hashimoto's thyroiditis (HT,n=7), papillary carcinoma (PC,n=12), Hashimoto's thyroiditis with papillary carcinoma (HTPC,n=5), and Graves' disease (GD,n=7) were examined by anin situ nucleotidyl transferase assay (ISNTA), which detects DNA fragmentation. Control normal thyroid tissue (NT,n=7) was obtained from surgically resected papillary thyroid carcinomas sampled away from the primary tumor. An immunohistochemical (IHC) method was used to detect bcl-2 expression. Positive ISNTA nuclei in thyroid follicular cells or tumor cells per section were counted in all parenchymal areas, excluding areas of lymphocyte aggregates. The intensity of bcl-2 staining was graded on a scale of 1+ to 3+. The number of ISNTA-positive thyroid follicular cells was a significantly higher in HT compared to GD. In addition, there was significantly lower number of ISNTA positive non-neoplastic thyroid follicular cells in HTPC compared to HT alone. Strong expression of bcl-2 was found in all cases of GD and NT, but much less bcl-2 staining was seen in HT. There was moderate expression of bcl-2 in HTPC and PC. These findings suggest that (1) DNA fragmentation of the thyroid follicular cells plays an important role in the thyroid injury in HT but not in GD, (2) expression of bcl-2 may overcome the apoptosis in GD but not in HT, and (3) downregulation of DNA fragmentation of the follicular cells in Hashimoto's thyroiditis associated with papillary carcinoma may suggest an important mechanism for tumor pathogenesis.

[Vestibular potentials evoked by electrical stimulation]

OBJECTIVE

To identify the evoked potentials (VsEPs) by electrical stimulation were from vestibule.

METHODS

The stimulating electrode was set on the round window of guinea pig. Constant current shocks of 0.05 ms (0.25-1.2 mA) were used to evoke VsEPs by means of vertex-pinna skin electrodes.

RESULTS

These potentials were short latencies of (0.973 +/- 0.086) ms, (1.618 +/- 0.176) ms and (2.416 +/- 0.274) ms respectively, which reflected true potentials and were not from electrical stimulus artefacts. It was pure vestibular origin. As being masked with a continuous white noise (120 dB SPL) or removed ipsilateral auditory nerve, and even after facial neurectomy, waves were still existing, but disapeared after selective vestibular neurectomy. The twitching responses in the facial region had never been detected during the whole test. These potentials were bioelectric responses in the vestibular sensory pathway, characterized by threshold saturation, adaptability of excitation, dependent on intact vestibular nerve.

CONCLUSIONS

We have set up animal model of recording VsEPs evoked by electrical stimulation on the round window of guinea pigs.

Effect of NO donors on LV diastolic function in patients with severe pressure-overload hypertrophy

BACKGROUND

Previous experimental studies have shown that nitric oxide (NO) modulates cardiac function by an abbreviation of systolic contraction and an enhancement of diastolic relaxation. However, the response to NO donors of patients with severe pressure-overload hypertrophy and diastolic dysfunction is unknown.

METHODS AND RESULTS

Intracoronary NO donors were given to 17 patients with severe aortic stenosis. A dose-response curve was obtained with nitroglycerin (30, 90, and 150 microg) in 11 patients and sodium nitroprusside (1, 2, and 4 microg/min) in 6. Left ventricular (LV) high-fidelity pressure measurements with simultaneous LV angiograms were performed at baseline and after the maximal dose of NO. The dose-response curve for intracoronary NO donors showed a marked fall in LV end-diastolic pressure, from 23 to 14 mm Hg (-39%; P<0.0001), whereas LV peak systolic pressure fell only slightly, from 206 to 196 mm Hg (-4%; P<0.01). End-diastolic chamber stiffness decreased from 0.12 to 0.07 mm Hg/mL (P<0.0001) and end-systolic stiffness from 1.6 to 1.3 mm Hg/mL (P<0.01). Heart rate, right atrial pressure, LV ejection fraction, the time constant of isovolumic pressure decay (tau), and LV filling rates remained unchanged.

CONCLUSIONS

In patients with severe pressure-overload hypertrophy, intracoronary NO donors exert a marked decrease in LV end-diastolic pressure without affecting LV systolic pump function. Thus, the hypertrophied myocardium appears to be particularly susceptible to NO donors, with a marked improvement in diastolic function.

[Advances in affinity chromatography]

This review is mainly concerned with the recent advances in (i) mechanism of affinity chromatography; (ii) the use of new techniques such as combinational chemistry, molecular imprinting, de novo design, fusion expression in discovery of ligand; (iii) improvement of support and chromatographic system; (iv) application of affinity chromatography. The review includes 66 references.

[Clinical study on preventive effect of taozhi zhipu mixture on postoperative intestinal adhesion]

OBJECTIVE

To study the clinical effect of Taozhi Zhipu Mixture (TZM) in preventing postoperative intestinal adhesion.

METHODS

Three hundred and ninety-six patients who had received abdominal operation were randomly divided into the treated group (188 cases) and the control group (208 cases). Same treatment was given to both groups excepting that the treated group received TZM orally or by nasogastric tube. The time of borborygmus recovering and first passing of flatus-defecation after operation was recorded. Patient's gastro-intestinal motion was observed by isotope tracing with I131 capsule. The frequency and intensity of borborygmus were measured by a tracer. All patients had been followed up for 2-3 years.

RESULTS

The recovery of borborygmus, the first passing of flatus-defecation were much earlier, the I131 capsule passed gastro-intestinal tract more quickly, and tracer showed higher frequency and intensity of borborygmus in the treated group than those in the control group. Follow-up study also showed the treated group was better than the control group in the non-adhesion rate and the total effective rate (P < 0.05).

CONCLUSION

TZM has good effect on stimulating postoperational gastro-intestinal peristalsis and preventing the occurrence of postoperational intestinal adhesion.

[Lactulose mannitol ratio in patients after operation]

OBJECTIVE

To study lactulose (lactulose, L) and mannitol (mannitol, M) ratio in urine following operation and investigate the correlation between severity of stress and L/M ratio.

METHODS

20 patients who had received operation were enrolled and each patient was evaluated by APACH II scores. L/M permeability study was performed before the operation and 5 and 10 days after the operation. The L and M concentration was analyzed by HPLC with pulsed electrochemical detection (HPLC-PED). The correlation between L/M ratio and the severity of surgical stress were related.

RESULTS

The L/M ratio before the operation was (0.023 +/- 0.002), increased to (0.042 +/- 0.005) in the 5th post-operative day (P < 0.01), and then returned to (0.024 +/- 0.002) (P > 0.05) compared with pre-operation in the 10th Post-operation. A significant correlation between the severity of stress and the L/M ratio was observed (r = 0.762).

CONCLUSIONS

The L/M ratio was increased 5 days after the operation and the L/M ratio was correlated with severity of operative stress.

Influence of additives on the protoplasts electrofusion

Various neutral or charged surface active substances were used for testing the influence of additives on the electrofusion of barley protoplasts. It was found that neutral surface active agents DX, TAGB, Span-80 and AEO-9 could promote the electrofusion. The positively charged surface active agents Bardac 2080, Bardac 2280 and amphoteric surface active agents dodecyl-propyl betaine and CAB betaine also promote the electrofusion, but at high concentration the electrofusion efficiency will reduce. The negatively charged polymer agents Cibacron blue DX, Fluoresceinylthiocarbamoyl DX, and active surface substances K12 and Carsonol TLS- presented negative effect. These phenomena were discussed from the view of adsorption of additives on the membrane and the interactions between protoplasts.

[Antitumor effect of tumor necrosis factor alpha and interferon gamma on human lung adenocarcinoma A549 cell line.]

BACKGROUND

To explore the synergistic antitumor effect of tumor necrosis factor alpha (TNF-alpha) and interferon gamma ( IFN-gamma) on human lung adenocarcinoma A549 cell line.

METHODS

Cell growth inhibition was determined byMTT colorimetry assay.

RESULTS

Both TNF-alpha and IFN-gamma showed directly growth inhibition on human lung carcinoma A549 cell line. IFN-gamma could enhance cell growth inhibition effect of TNF-alpha when used together.

CONCLUSIONS

TNF-alpha and IFN-gamma displayed significant synergistic antitumor effect on human lung adenocarcinoma A549 cell line. These results give experimental evidence for the multimodality therapy of human lung cancer and other tumors.

Characterization of a dCTP transport activity reconstituted from human mitochondria

A protein fraction of mitochondria from human acute lymphocytic leukemia cells, which could be reconstituted into proteoliposomes to have dCTP transport activity, has been partially purified by hydroxyapatite and blue Sepharose chromatography. The dCTP transport activity in proteoliposomes was time-dependent and could be activated by Ca2+ and to a lesser extent by Mg2+. None of the other divalent cations tested could activate the transport activity. The Km value of dCTP in the presence of Ca2+ was shown to be 3 microM. dCDP but not dCMP or dCyd could inhibit the transport activity. Other deoxynucleoside triphosphates could also inhibit the uptake of dCTP with the potency dGTP = dATP > TTP. Although ATP could competitively inhibit dCTP uptake with a Ki value of 8 microM, the reconstituted dCTP uptake activity was not sensitive to the ATP/ADP carrier inhibitor atractyloside or the sulfhydryl reagent N-ethylmaleimide. This suggests that the dCTP transport system studied is not the same as the ATP/ADP carrier. In conclusion, these studies describe the first functionally reconstituted mitochondrial carrier that displays an efficient transport activity for dCTP.

[Trace analysis of Zn-doped compound semiconductor material by resonant ionization mass spectrometry]

An experimental setup and the procedure for the laser resonant ionization mass spectrometry (RIMS) have been described. Both an optical spectrum and a mass spectum have been shown. The detection limit that can be reached by using this procedure has been estimated.

[Determination of trace aluminium by ETV-ICP-AES]

The effect of mixed halogenation agent (polytrifluorochloroethylene (PTFCE)/hexachloroethane (C2Cl6)) on the vaporization of aluminium has been studied in electrothermal vaporization inductively coupled plasma atomic emission spectrometry (ETV-ICP-AES). The mixed halogenation agent hastens the vaporization of Al to the plasma at low temperature compared with individual halogenation agent, and the metallic material can be prevented affectively from forming in the furnace. The detection limit of this method was 0.12 ng with RSD of 3.8% (Al: 0.3 microg x mL(-1), n = 7). The analytical results of real samples were in good agreement with those of pheumatic nebulization (PN)-ICP-AES, and the recoveries were in the range of 94.1%-102.5%.

An in vitro functionally mature mouse spinal cord preparation for the study of spinal motor networks

An in vitro isolated whole spinal cord preparation has been developed in 'motor functionally mature' mice; that is mice of developmental maturity sufficient to weight-bear and walk. In balb/c mice this stage occurs at around postnatal day 10 (P10). Administration of strychnine elicited synchronous activity bilaterally in lumbar ventral roots. Rhythmic alternating locomotor-like activity could be produced by application of a combination of serotonin (5-HT), N-methyl-d-aspartate (NMDA), and dopamine in animals up to P12. Using a live cell-dead cell assay, it is demonstrated that there are primarily viable cells throughout the lumbar spinal cord. The viability of descending pathways was demonstrated with stimulation of the mid-thoracic white matter tracts. In addition, polysynaptic segmental reflexes could be elicited. Although usually absent in whole cord preparations, monosynaptic reflexes could invariably be elicited following longitudinal midline hemisection, leading to the possible explanation that there might be an active crossed pathway producing presynaptic inhibition of primary afferent terminals. The data demonstrate that this functionally mature spinal cord preparation can be used for the study of spinal cord physiology including locomotion.

Fimbria-mediated enhanced attachment of nontypeable Haemophilus influenzae to respiratory syncytial virus-infected respiratory epithelial cells

Respiratory syncytial virus (RSV) infection is known to predispose children to otitis media and sinusitis due to bacteria such as nontypeable Haemophilus influenzae (NTHI). In this study, we investigated the role of NTHI surface outer membrane protein P5-homologous fimbriae (P5-fimbriae) in attachment to RSV-exposed A549 epithelial cells. Analysis by fluorescence flow cytometry showed that a live P5-fimbriated NTHI strain (NTHIF+) attached to a higher proportion of RSV-exposed A549 cells than to control cells (mean, 68% for RSV versus 29% for control; P = 0.008), while attachment of the P5-fimbriae-deficient isogenic mutant strain (NTHIF-) was significantly lower than in control cells and rose only slightly following RSV exposure (mean, 17% for RSV versus 10% for control, P = 0.229). Attachment of NTHIF+ did not correlate with the amount of RSV antigen expressed by A549 cells. Furthermore, paraformaldehyde-fixed NTHIF+ also demonstrated an enhanced binding to RSV-exposed cells. Observations by transmission electronic microscopy showed that the mean number of bacteria attached per 100 RSV-exposed A549 cells was higher for NTHIF+ than NTHIF- (99 versus 18; P < 0.001). No intracellular bacteria were identified. UV-irradiated conditioned supernatants collected from RSV-infected A549 cultures (UV-cRSV) also enhanced the attachment of NTHIF+ to A549, suggesting the presence of a preformed soluble mediator(s) in UV-cRSV that enhances the expression of receptors for P5-fimbriae on A549 cells. In summary, RSV infection significantly enhances NTHI attachment to respiratory epithelial cells. P5-fimbria is the critical appendage of NTHI that participates in this attachment. In clinical settings, blocking of the P5-fimbria-mediated attachment of NTHIF+ by passive or active immunity may reduce the morbidity due to NTHI during RSV infection.

Toward a dog radiation hybrid map

Dog fibroblasts grown from a biopsy performed in a male mongrel were fused after gamma irradiation with thymidine kinase-deficient hamster cells and cultivated in selection medium. A total of 148 clones were obtained and screened by means of PCR amplification using primers corresponding to a dog-specific short repetitive element and to dog microsatellites and genes. One hundred seven cell lines were selected and grown in roller bottles and the distribution of 39 markers was analyzed in the extracted DNA. The results clearly indicate that this panel of hybrid cell lines should prove invaluable for constructing a map of the canine genome. In parallel, for more than 500 microsatellites present in the databases or screened from two libraries of short inserts, we have determined PCR conditions favoring dog-specific products even in the presence of hamster DNA. These highly polymorphic microsatellites should be useful in further linkage studies. We have also characterized 254 markers: dog genes, human expressed sequenced tags (huESTs), and traced orthologous amplified sequenced tags (TOASTs). Once mapped, these will constitute powerful tools to detect regions of conserved synteny in human and other mammalian genomes.

Use of GPS ASHTECH Z12T receivers for accurate time and frequency comparisons

The GPS phase measurements described in this paper were obtained using two similar multichannel GPS ASHTECH Z12T receivers belonging to the Bureau International des Poids et Mesures, BIPM, and the Laboratoire Primaire du Temps et des Frequences, BNM-LPTF. These receivers are based on the conventional geodetic ASHTECH Z12 unit, which has been modified to meet the stability requirements of time and frequency comparisons. Comparison of the two receivers operated side by side in different antenna configurations shows typical short-term noise of 1.1 to 3.5 ps. Longer term variations indicate a temperature sensitivity in the equipment, which limits the performance of the GPS phase method. One of the receivers was successfully operated using a temperature-stabilized antenna TSA from 3S Navigation, and the ASHTECH antenna, which feeds the second receiver, was placed in a home-built oven maintained at a constant temperature. These precautions made it possible to reduce a number of systematic effects. A separate study of frequency comparison was carried out between two hydrogen-masers located at the BNM-LPTF (Paris, France) and the PTB (Braunschweig, Germany) using receivers similar to ASHTECH Z12T receivers. The relative frequency stability obtained was about 3.3x10(-15) for an average time of 15 000 s, an interesting result comparable with the outstanding performance of new ultrastable frequency standards.

Human and rodent MaxiK channel beta-subunit genes: cloning and characterization

Voltage- and Ca2+-sensitive K+ (MaxiK) channels play key roles in controlling neuronal excitability and vascular tone. We cloned and analyzed human and rodent genes for the modulatory beta subunit, KCNMB1. The human and mouse beta-subunit genes are approximately 11 and approximately 9 kb in length, respectively, and have a four exon-three intron structure. Primer extension assay localized the transcription initiation site at 442 (human) or 440 (mouse) bp upstream of the translation initiation codon, agreeing with the transcript size in Northern blots. Both genes have a TATA-less putative promoter region, with a transcription initiator-like region, and motifs characteristic of regulated promoters, including muscle-specific enhancing factors-1 and -2. Consistent with a tissue-specific expression of KCNMB1, regulated at the transcriptional level, beta-subunit transcripts are abundant in smooth muscle and heart, but scarce in lymphatic tissues, brain, and liver. Expressed rat and mouse beta subunits increase the apparent Ca2+ sensitivity of the human MaxiK channel alpha subunit.

A whole-genome radiation hybrid map of the dog genome

A whole genome radiation hybrid (RH) map of the canine genome was constructed by typing 400 markers, including 218 genes and 182 microsatellites, on a panel of 126 radiation hybrid cell lines. Fifty-seven RH groups have been determined with lod scores greater than 6, and 180 framework landmarks were ordered with odds greater than 1000:1. Average spacing between adjacent markers is 23 cR5000, an estimated physical distance of 3.8 Mb. Fourteen groups have been assigned to 9 of the canine chromosomes, and a comparison of RH and genetic groups allowed the successful bridging of both types of data on one map composed of 31 RH and 13 syntenic RH groups. Comparison of canine, human, mouse, and pig maps underlined regions of conserved synteny. This integrated map, covering an estimated 80% of the dog genome, should prove a powerful tool for localizing and identifiying genes implicated in pathological and phenotypical traits.

Autocrine regulation of interleukin-8 by interleukin-1alpha in respiratory syncytial virus-infected pulmonary epithelial cells in vitro

Respiratory epithelial cells infected with respiratory syncytial virus (RSV) produce interleukin-8 (IL-8); however, the mechanisms of RSV-induced regulation of IL-8 are poorly understood. In the present study, the regulation of IL-8 by RSV was evaluated using pulmonary type II-like epithelials (A549). Live purified RSV (pRSV) induced a significant increase in IL-8 after 8 hr of exposure, while conditioned supernatants from pRSV-infected A549 cells (cRSV) induced IL-8 production in fresh A549 cultures within 4 hr of infection. Furthermore, cRSV that had been rendered non-infectious by ultraviolet-irradiation (UV-cRSV) or ribavirin treatment also induced an increased production of IL-8 in fresh A549 cells, suggesting that RSV induced the synthesis of a soluble mediator(s) which in turn enhanced the synthesis of IL-8. We have previously shown that RSV-infected A549 cells produce IL-1alpha, IL-1-beta and tumour necrosis factor-alpha (TNF-alpha), which by themselves are known to induce the synthesis of IL-8. Preincubation of UV-cRSV or simultaneous incubation of pRSV with recombinant IL-1 receptor antagonist almost completely blocked (95-98%) the production of IL-8 by A549 cells. Furthermore, incubation with neutralizing antibodies against IL-1alpha, IL-1beta and TNF-alpha showed that IL-1alpha was the predominant soluble mediator that enhanced the mRNA expression and synthesis of IL-8. IL-1beta and TNF-alpha induced the synthesis of IL-8 at 24 hr, but partially inhibited the synthesis at 48 hr. In summary, these experiments provide direct evidence for an autocrine mechanism of enhanced IL-8 production in RSV-infected epithelial cells that is primarily mediated by IL-1alpha. In clinical settings, inhibitors of IL-1alpha may be useful in suppressing inflammation due to IL-1alpha as well as IL-8.

[Dietary fiber protects intestinal structure and barrier function]

OBJECTIVE

To evaluate the effect of dietary fiber on intestinal structure and barrier function of 5-fluorouracil (5-Fu) challenged rat.

METHOD

Thirty Wistar rats were divided randomly into three groups (10 each group): Chow, enteric nutrition (EN), and EN + Fiber group. Both EN and EN + Fiber group were isonitrogenic and isocaloric. The rats kept their diet respectively for 8 days. 5-Fu was injected intraperitoneally on day 4 postoperatively. Intestinal permeability (L/M) was measured respectively on day 3 and day 7. On day 8, the bacterial translation, wet weight and mucous thickness of both small intestine and colon and the villus height of small intestine were measured. The rats were weighted before and after experiment respectively.

RESULT

The body weight loss of the EN + Fiber group (-3.1 +/- 3.4 g) was less than that of the EN group (-6.6 +/- 5.2 g) (P < 0.05), whereas the Chow group gained body weight (4.9 +/- 4.3 g) (P < 0.01 when compared with EN and EN + Fiber group). The parameters of intestinal structures of the EN + Fiber group was superior to the EN group (P < 0.05). The L/M of both EN + Fiber (from 0.0265 +/- 0.0073 to 0.0274 +/- 0.0068) and the Chow group (from 0.0268 +/- 0.0039 to 0.0281 +/- 0.0044) was unchanged (P > 0.05 for both) after 5-Fu challenged, whereas that of the EN group increased (from 0.0289 +/- 0.0070 to 0.0331 +/- 0.0084) (P < 0.01). The incidence of bacterial translocation to MLN of both EN + Fiber group and the Chow group (20%) was lower than that of the EN group (70%) (P < 0.05).

CONCLUSION

The dietary fiber protects the intestinal structure and barrier function of 5-Fu challenged rats.

Expression of ICAM-1, VCAM-1, and LFA-1 in adenocarcinoma of the lung with observations on the expression of these adhesion molecules in non-neoplastic lung tissue

Intercellular adhesion molecule (ICAM-1), vascular cell adhesion molecule (VCAM-1), and the lymphocyte function-associated antigen (LFA-1) are cell adhesion molecules thought to play an important role in the complex process of airway inflammation and tumor cell growth. The aim of this study was to examine the distribution of ICAM-1, VCAM-1, and LFA-1 in adenocarcinoma of lung and in major cellular compartments of non-neoplastic lung tissue. We examined cellular compartments in tissue from five bronchoalveolar carcinomas, three acinar adenocarcinomas, and one colon cancer metastatic to the lung. The compartments in neoplasms included the tumor cells proper, endothelial cells within the tumor vasculature, tumor stromal cells, and tumor-infiltrating lymphocytes. The compartments in non-neoplastic lung tissue included lung endothelial cells, pulmonary lymphocytes, interstitial fibroblasts, Type II alveolar pneumocytes, and bronchial epithelial cells. ICAM-1 was expressed in tumor cells from all of the nine adenocarcinomas. In contrast, VCAM-1 expression was not identified in tumor cells from any of the nine adenocarcinomas. ICAM-1 was expressed in all cellular compartments of the non-neoplastic lung tissue, whereas VCAM-1 was expressed only in pulmonary lymphocytes and interstitial fibroblastic cells. LFA-1 was uniformly expressed in tumor-infiltrating lymphocytes from each of the nine tumors and all of the lymphocytes in non-neoplastic lung tissue. This study showed major differences in the expression of ICAM-1 and VCAM-1 in tumor cells from pulmonary adenocarcinoma and also provided evidence for a wider distribution of ICAM-1, compared with VCAM-1, in non-neoplastic cellular compartments of the lung. ICAM-1 expression was particularly noticeable in bronchial and alveolar epithelial cells. Upregulation of ICAM-1 in pulmonary adenocarcinoma might foster binding by LFA-1-bearing lymphocytes, with a possible impact on the vulnerability of tumor cells to host defense mechanisms.

Prevalence of human melioidosis on Hainan Island in China

Eight human cases of melioidosis were diagnosed at Hainan People's Hospital over a period of one year. Four of the cases were of septicemia form, while the rest were of chronic form with abscesses in different organs. All the isolates were intrinsically resistant to cefazolin, cefuroxime, and gentamicin, while being rather sensitive to ampicillin/sulbactam, ticarcillin/clavulanic acid, and imipenem. A serological survey of exotoxin antibodies at different farms showed that Xinglong was a farm seriously devastated by Burkholderia pseudomallei, while the mountainous farm of Licai had the lowest prevalence (P< 0.01). From the results of serological survey and melioidosis case distribution, it could be clearly seen that melioidosis predominantly exists in coastal plain regions around this island, where the altitude above sea-level is below 100 m, the annual rainfall is up to 2,300 mm and a rather warm climate in coldest months of December and January.

Two linear acetogenins from Goniothalamus gardneri

Two new acetogenins, gardnerilins A and B, have been isolated from the roots of Goniothalamus gardneri. Both are C35 acetogenins containing non-tetrahydrofuran rings. Their structures have been established on the basis of spectral evidence.

Human magnetic resonance imaging at 8 T

In this work, we present the first human magnetic resonance image (MRI) obtained at ultrahigh field strengths (8 T). We demonstrate that clinical imaging will be possible at 8 T and that reasonable quality head images can be obtained at this field strength. Most importantly, we emphasize that the power required to excite the spins at 8 T is much lower than had previously been predicted by the nuclear magnetic resonance theory. A 90 degree pulse in the head at 8 T requires only approximately 0.085 J of energy (90 W for a 2-lobe 4 ms sinc pulse). Based on measurements at 4 T, 1-2 J of energy should have been utilized to achieve a 90 degree excitation at 8 T. The fact that the energy required for spin excitation at 8 T is much lower than predicted by the NMR theory, will be extremely important to the viability of ultrahigh field imaging, since concerns related to power absorption and specific absorption rate (SAR) violations at ultrahigh field are alleviated. As such, it will be possible to utilize RF intensive pulse sequences and adiabatic spin excitation at 8 T without significant risk to the subject.

Cytokine modulation of human corneal epithelial cell ICAM-1 (CD54) expression

To determine whether pro-inflammatory cytokines modulate intercellular adhesion molecule-1 (ICAM-1; CD54) expression on cultured primary human corneal epithelial cells (HCEs), confluent HCEs were treated with various concentrations of interferon-gamma(IFN-gamma), interleukin-1alpha(IL-1alpha), IL-1beta, IL-4, tumor necrosis factor-alpha (TNF-alpha), or combinations over time. ICAM-1 expression was measured by flow cytometry and/or a cell-based ELISA using a monoclonal mouse anti-human CD54 antibody. The apparent MW of ICAM-1 protein was determined by immunoprecipitation of biotinylated HCEs. RT-PCR was used to detect ICAM-1 RNA. The mature cell surface form of HCE ICAM-1 was approximately 110 kDa as determined by immunoprecipitation. IFN-gammaand TNF-alpha induced both dose- and time-dependent increases in ICAM-1 expression. An approximately 20-fold increase in ICAM-1 was seen at 50-100 U IFN-gamma ml-1. ICAM-1 specific mRNA accumulated approximately 4.5-fold after IFN-gammatreatment. TNF-alpha(100 U ml-1) induced a consistent approximately 6.0-fold increase in ICAM-1 expression. When IFN-gammaand TNF-alpha were mixed, at sub-optimal concentrations of each, a synergistic effect on ICAM-1 expression was not detected. Neither IL-4, IL-1alpha nor IL-1beta affected ICAM-1 expression in a consistent fashion. In summary, ICAM-1 was modulated on primary human corneal epithelial cells by the cytokines IFN-gamma and TNF-alpha in a dose- and time-dependent fashion. Cytokine modulation of corneal epithelial cell ICAM-1 during inflammation may contribute to corneal epithelial cell injury by aiding the attachment of inflammatory cells such as eosinophils which express the receptor for ICAM-1, the beta2 integrins (CD11a,b,c/CD18).

In vivo investigation of blood compatibility of titanium oxide films

Titanium oxide films were synthesized by ionbeam-enhanced deposition. The films were prepared by depositing titanium atoms and simultaneously bombarding them with Xe+ ions at an energy of 40 keV in an O2 environment. An in vivo investigation, which entailed implanting low-temperature isotropic pyrolytic carbon (LTI carbon) cylinders, widely used to fabricate artificial heart valves, and titanium-oxide-coated LTI carbon cylinders with diameters of 5 mm and thicknesses of 0.5 mm into the ventral aorta of dogs for 14 days, showed that the amount of thrombus on the titanium-oxide-coated LTI carbon was much less than that formed on the surface of LTI carbon alone. Scanning electron microscopy (SEM) was used to observe the morphology of thrombus. On the titanium oxide films no platelet aggregation was found, almost no red blood cells were damaged, and almost no fibrin was found on the surface. However, all three characteristics were found on the surface of LTI carbon alone, proving that the blood compatibility of titanium oxide films is better than that of LTI carbon and titanium-oxide-coated LTI carbon.

Linear acetogenins from Goniothalamus donnaiensis

Four linear acetogenins, donhepocin (1), 34-epi-donhepocin (1'), donhexocin and donbutocin, have been isolated from the roots of Goniothalamus donnaiensis. 1 and 1', isolated as an epimeric pair, contain a rare gamma-hydroxymethyl-gamma-lactone. Their structures have been established on the basis of spectral and chemical evidence.

[Joint effects of arsenic and lead on lipid peroxidation of human and rat erythrocytes]

The authors observed the joint effects of arsenic and lead on lipid peroxidation(LPO) in vitro and in vivo. In vitro, the authors used the extracted erythrocyte membrane of health adult men and divided them into three exposed groups. The first group was exposed to As2O3 (0, 0.4, 2.0 and 10.0 mmol/L). The second group was exposed to PbAc2 (0, 0.08, 0.4 and 2.0 mmol/L). The third group was exposed to As(10 mmol/L) + Pb (0.08 mmol/L). The results show that there is interaction between As and Pb on LPO of erythrocyte membrane. In vivo, the authors measured LPO levels of rat's plasma, blood glutathione(GSH) and superoxide dismutase(SOD) activity. By using 2 x 2 factorial design, Wistar rats were gavaged with As2O3 2.4 mg/(kg.d) and PbAc2 30 mg/(kg.d) as well as both arsenic and lead in water for 10 days. The results show that in the As-Pb treated rats, the levels of LPO did not change significantly, the GSH levels and SOD activity decreased significantly. The results of factorial analysis revealed a synergic effect of As-Pb on SOD activity.

Use of interactive-intraoperative guidance during vertebrectomy and anterior spinal fusion with instrumental fixation: technical note

Anterior decompressive procedures for the treatment of vertebral tumors have become increasingly popular in an attempt to improve the quality of life, relieve pain, and preserve or restore neurologic function. However, these procedures carry a significant rate of complications including hardware failure, due in part to technical factors. A computer-assisted system allowing for precise preoperative planning and real-time intraoperative interactive image localization has been implemented for spine instrumentation to optimize anterior instrumental fixation. We discuss our initial clinical experience and application to anterior vertebrectomy, and vertebral reconstruction with anterior instrumental fixation. We believe that computer-assisted spine surgery using infrared-based technology offers the necessary elements to make its use fast, reliable, and intuitive, providing an accurate and safe approach for optimization of spine surgery.

[Studies on tannins from Tripterygium hypoglaucum (lévl.) hutch]

OBJECTIVE

To study the tannins from Tripterygium hypoglaucum.

METHOD

Compounds were isolated by column chromatography and elucidated on the basis of spectroscopic analysis and comparison of references.

RESULT

The compounds obtained were determined as (+)catechin, (-)epigallocatechin, procyanidin B-3, procyanidin B-4 and gallocatechin-(4 alpha-->8) epicatechin.

CONCLUSION

All the compounds were obtained from this plant for the first time.

Study on Haemophilus influenzae type b diseases in China: the past, present and future

Meningitis caused by Haemophilus influenzae type b (Hib) is a common and serious disease for which there now are WHO-certified vaccines that are recommended for universal infant immunization in North America and European countries. If these vaccines are to be recommended in Asia, it is necessary to know the incidence, age distribution and clinical outcome of Hib meningitis and other systemic infections in this region. Data on Hib disease in China are scanty. Hib meningitis was common during the 1950s in China, accounting for up to 16% of all of pyogenic meningitis (up to 38% of cases were caused by unknown pathogens), despite severe epidemics of meningococcal meningitis during that period. Since 1989 we have conducted hospital- and community-based etiologic and epidemiologic studies of bacterial meningitis. Hib accounts for 30 to 50% of bacterial meningitis in China. The incidence of Hib meningitis in Hefei City was 10.4 per 100000 children <5 years, a result relatively lower than in the West but higher than the rate of 2.7 found in a retrospective study in Hong Kong. Pneumonia is the primary cause of death for Chinese children. From 1991 to 1993 the average mortality of children<5 years because of pneumonia was 1563.2 per 100000. To achieve the goal of reducing the death rate of children by one-third by the year 2000, greater efforts should be made to reduce the mortality of children with pneumonia. Our preliminary study showed that about one-fourth to one-third of cases of pneumonia in Chinese children might be caused by Hib. Therefore Hib vaccination for infants and children in China might be an effective and valuable procedure to achieve the goal.

[Application of stress urethral pressure profile for diagnosis and treatment of stress incontinence]

OBJECTIVE

To apply the stress urethral pressure profile (SUPP) to diagnose the genuine stress incontinence (GSI) and to evaluate the results of treatment.

METHOD

22 patients with GSI underwent SUPP and rest urethral pressure profile (RUPP) using Dantec Menuet.

RESULT

The results showed that the pressure transmission ratio (PTR) was 0.68 +/- 0.06, and urethral close pressure (UCP) was -0.62 +/- 0.22 kPa in 22 patients. PTR and UCP raised significantly after operation in 5 patients, P < 0.01. The results of SUPP were compared with those RUPP.

CONCLUSION

SUPP is important in both diagnosis and evaluation of GSI, although some limitation exists. To improve the level of diagnosis, it should be combined with other method in clinical use.

Effect of aspirin on protein binding and tissue disposition of oligonucleotide phosphorothioate in rats

Pharmacokinetic studies of phosphorothioate oligodeoxynucleotides (PS-oligonucleotides) in animals show that following intravenous administration, PS-oligonucleotide clears out rapidly from the plasma and is distributed to majority of the organs. PS-oligonucleotides are bound to plasma proteins extensively. This study was aimed to determine the effect of aspirin, a commonly used drug, on pharmacokinetics of PS-oligonucleotides. In the present study, PS-oligonucleotide was administered to rats that had received aspirin by gavage. Pharmacokinetic study shows that if PS-oligonucleotide was administered following aspirin administration in rats, a) plasma pharmacokinetic parameters (t1/2alpha?, t1/2beta, AUC, etc.) had lower values, b) tissue disposition was different, and c) rate and route of elimination was affected in animals compared to rats receiving PS-oligonucleotide alone. This finding suggests that pharmacokinetics of PS-oligonucleotides can be affected with certain class of drugs, which may have direct impact on biological activity and safety.

[A case-control study on the risk factors of accidental injury among 0-14 year-old children]

To investigate the risk factors resulting in accidental injury in children and to provide basis for the prevention and reduction of such incidence, 468 cases of children with accidental injuries were studied through a one to one matched case-control study. Data was analysed with conditional logistic analysis. Results from single-factor analysis showed that such cases were associated with following factors: a) multiple children in the family with parents illiterate or low income; b) pesticide or raticide was stored inside the rooms; c) negligence of the dangerous environment risk around their houses. Results from multiple-factors analysis showed that children with illiterate parents, house that had pesticide stored in, low family income and whose houses were under vulnerable condition of collapse were most likely to suffer accidental injuries. Author concluded that the accidental injuries to children were caused by multiple factors which are preventable.

[The importance of the canine model in medical genetics]

Dog domestication dates back to as early as 100,000 years ago, or 10,000 years depending upon the data used, and nowadays more than 350 breeds are duly registered in the different kennel clubs around the world. Due to intensive selection in the course of breeding, dog presently comes in any shape, size, color one can imagine, in addition to displaying a wide panel of characters, capacities and behaviours. As a consequence of excessive breeding, numerous breeds are plagued by a large variety of genetic diseases, many of them resembling those observed in human. All this makes dog an attractive model to track down genes and alleles responsible for those phenotypic behavioural or pathological traits, provided a genome map with polymorphic markers, and genes is available.

Single-shot spatiotemporal terahertz field imaging

Using an optically chirped pulse in an electro-optic detection system, we image the spatiotemporal distribution of a terahertz (THz) pulse. We demonstrate single-shot THz field imaging of photoconductive emitters.

Experimental study on distribution of serotypes and antimicrobial patterns of group B streptococcus strains

OBJECTIVE

To obtain information on the distribution of serotypes and antimicrobial agent susceptibilities to group B streptococcus (GBS) strains isolated in Beijing area from 1991 to 1996.

METHODS

Bacterial isolates of GBS were obtained from vaginal and cervical tract of pregnant and nonpregnant women in Beijing Tian Tan Hospital by culture. A total of 76 GBS strains were identified finally by coagglutination. Serotyping was determined by Standard Lancefield method. Susceptibility to test agents was assessed by determining the minimal inhibitory concentrations (MICs) with agar dilution method that was established by the National Committee for Clinical Laboratory Standards (NCCLS).

RESULTS

Seven serotypes were identified among 76 GBS strains isolates. Types II (33%), III (23%) and I a (16%) were the predominant serotypes in pregnant and nonpregnant women. MICs of penicillin G and ampicillin were < or = 0.06 microgram/ml. MICs of cephazolin, cefuroxime and cefoperozone were 0.003 microgram/ml-0.06 microgram/ml. MICs of erythromycin were 0.003 microgram/ml-0.03 microgram/ml. MICs of gentamycin were 1 microgram/ml-32 micrograms/ml. MICs of amikacin were 4 micrograms/ml- > or = 64 micrograms/ml, nearly 12.8% and 40.4% of the strains were resistant to gentamycin and amikacin, respectively.

CONCLUSIONS

Our study provides useful epidemiologic data for preparation of GBS type-specific vaccines which can prevent GBS infections and antimicrobial agents susceptibility patterns in China. Routine reports on GBS susceptibilities by clinical laboratories and continuous surveillance for changes in the susceptibility are of considerable clinical importance.

Traced orthologous amplified sequence tags (TOASTs) and mammalian comparative maps

Progress on mammalian comparative maps could be significantly accelerated by developing reagents defining orthologous landmarks in the genome of many mammalian species. Using the large databases of gene sequences, we designed 225 orthologous gene-specific primer pairs corresponding to 146 functional genes. Of these 225 primer pairs, 155 (68.9%), 182 (80.9%), 126 (56.0%), and 82 (36.4%) produced a single PCR product when tested against human, pig, dog, and hamster genomic DNA, respectively. In addition to the general rules of primer designing, particular factors must be taken into consideration when choosing gene-specific universal primers--for instance, preference for single-exon regions or highly conserved segments among species, avoidance of GC-rich regions. Sequencing all the canine PCR products traced by these primers demonstrated that of 123 traced canine fragments with readable and reliable sequences, 121 (98.4%) were found to match the GenBank orthologous sequences used for designing the primers, after a BLAST search. Comparative characterization of PCR fragments among human, pig, dog, and hamster revealed that the length of a single exon was much conserved among species, with few exceptions. As the fragments were traced with amplification by orthologous gene-specific primers, we suggest they be termed Traced Orthologous Amplified Sequence Tags (TOASTs).