[Improved retrosigmoid approach operation in the treatment of trigeminal neuralgia]

OBJECTIVE

To explore the surgical method which can raise the treatment effect and reduce the complication occurrence of cerebellopontine angle (CPA) operation by retrosigmoid approach.

METHOD

Have improved the retrosigmoid approach in the skin incision, the hole position of bone, the intracranial operation skills and the duramatral suture, etc. By the improved retrosigmoid approach, we used partial sensory rhizotomy (PSR) to cure 54 cases with trigeminal neuralgia (TN).

RESULT

52 cases got satisfactory treatment effect and no complication appeared. In the other 2 cases, the trigeminal nerve was not found in CPA.

CONCLUSION

The CPA operation by retrosigmoid approach is dangerous relatively, it usually can cause some serious complication. But improved retrosigmoid approach can expose CPA sufficiently and is convenient to operate. On the other hand, it can decrease intracranial unexpected hemorrhage and complication occurrence.

[Selective excitation spectra and energy level structure of Dy3+:ThO2 crystal]

Dy3+:ThO2 crystal was grown by the flux technique for the first time. The emission spectra, excitation spectra and fluorescence decay curves were measured and discussed. By using emission spectra obtained under selective dye laser excitation at 12 K, together with the crystal-field theory, the site symmetry of Dy3+ ions in ThO2 was determined as C3 nu and its energy level structure was tabulated. The lifetime of radiative level 4F9/2 was also determined as 0.40 ms.

[Inhibitory effect of gelsemium alkaloids extract on hepatic carcinoma HepG2 cells in vitro]

The inhibitory effect of gelsemium alkaloids exstract (GAA) on HepG2 cells in vitro were studied by crystal violet dyeing method. The morphological change of HepG2 cells were observed with optical microscope. The alterations of cell cycle induced by GAA were analyzed with flow cytometry. The results showed that HepG2 cells exposed to GAA 10 micrograms/ml was inhibited significantly (P < 0.05). The inhibitory effect appeared in a dose- and time-dependent manner. HepG2 cells showed nuclear chromosome segmentation and condensation after GAA treatment. There emerged obvious Sub-G1 peak in the DNA histogram of HepG2 cells. GAA has a significant inhibition on HepG2 cells in vitro. The mechanism of antitumor action may be related to their apoptosis inducing activity.

[The effect of sinoaortic denervation by five selective methods on baroreflex sensitivity in conscious rats]

AIM

To measure the acute and chronic effects of left or/and right sinoaortic denervation (SAD), aortic denervation, and sinus denervation on baroreflex sensitivity (BRS) in conscious rats.

METHODS

BRS was measured by means of a modified Smyth's method. The acute and chronic effects experiments were executed in 1st and 21st days after selective SAD respectively to compare the compensatory function.

RESULTS

(1) BRS decreased significantly after selective SAD. BRS of right SAD was significantly lower than that of left SAD, but they were able to compensate for each other. (2) The decrease in BRS of aortic denervation was more significant than that of sinus denervation, but the former had no significant compensatory function, which was different from the latter.

CONCLUSION

As for baroreflex, right sinoaortic nerves are more important than the left, but their ability to compensate for each other is comparable. Meanwhile, aortic nerves are more important than sinus nerves, and so is their compensatory function.

Development of an intragastric enteral model in the mouse: studies of alcohol-induced liver disease using knockout technology

The establishment of a continuous intragastric enteral feeding protocol in the rat by Tsukamoto and French was a major development in research of alcohol-induced liver disease. Unlike other models which only produce fat, with this model, inflammation, necrosis, and fibrosis can now be studied. However, much of what has been learned to date involves inhibitors or nutritional manipulation which may not be specific. Knockout technology could avoid these potential problems. Therefore, we have adapted a rat long-term intragastric protocol to the mouse so that the knockout technology can be used to study the mechanism of alcohol-induced liver injury. Reactive free radicals are involved in the mechanisms of early alcohol-induced liver injury; however, the key source of these species remains unclear. Cytochrome P450 (CYP) 2E1 is induced predominantly in hepatocytes by ethanol and could be one source of reactive oxygen species leading to liver injury. On the other hand, NADPH oxidase or xanthine oxidase is also a potent source of free radicals. In studies using CYP2E1 and p47phox (NADPH oxidase-deficient) knockout mice with this enteral model, it was reported that oxidants from CYP2E1 play only a small role in the mechanisms of early alcohol-induced liver injury in the mouse. Further, free radicals from NADPH oxidase in Kupffer cells play an important role in early alcohol-induced liver injury. Thus, this new enteral mouse model using knockout technology will provide a powerful tool in alcohol research.

Delivery of the Cu/Zn-superoxide dismutase gene with adenovirus reduces early alcohol-induced liver injury in rats

BACKGROUND AND AIMS

Alcohol-induced liver injury is associated with an increase in oxidants from a variety of possible sources. Therefore, it was hypothesized that increased and stable expression of the antioxidant enzyme Cu/Zn-superoxide dismutase (SOD1) would diminish oxygen free radicals and reduce alcohol-induced liver injury.

METHODS

To test this hypothesis, rats were given recombinant adenovirus containing Cu/Zn-superoxide dismutase (Ad.SOD1) or beta-galactosidase (Ad.lacZ) and fed ethanol enterally for 3 weeks.

RESULTS

SOD was increased significantly 3-5-fold over endogenous levels in both hepatocytes as well as Kupffer cells 3 weeks after infection. Serum transaminase levels and pathology were elevated significantly in Ad.lacZ-treated animals by using an intragastric feeding model. This effect was blunted significantly in Ad.SOD1-infected animals. Importantly, electron spin resonance-detectable free-radical adducts caused by ethanol were also decreased by SOD1 overexpression. Moreover, the increase in nuclear factor kappaB (NFkappaB), tumor necrosis factor alpha (TNF-alpha), and interleukin 1 messenger RNA (mRNA) caused by ethanol was blunted in animals treated with Ad.SOD1.

CONCLUSIONS

These data support the hypothesis that oxidant production is critical in early alcohol-induced liver injury and that gene delivery of antioxidant enzymes may be useful in prevention and treatment.

Viral delivery of superoxide dismutase gene reduces cyclosporine A-induced nephrotoxicity

BACKGROUND

Cyclosporine A (CsA) increases free radical formation in the kidney. Accordingly, this study investigated whether gene delivery of superoxide dismutase (SOD) reduced radical production and nephrotoxicity caused by CsA.

METHODS

Rats were given adenovirus (Ad) carrying lacZ or Cu/Zn-SOD genes three days prior to CsA treatment. Histology, glomerular filtration rates (GFRs) and free radical adducts in urine were assessed.

RESULTS

SOD activity was increased 2.5-fold three days after viral infection and remained at 2- and 1.6-fold higher 10 and 17 days later. Treatment with CsA for seven days decreased GFR by 70% in rats infected with Ad-lacZ as expected; however, the decrease was diminished significantly in rats receiving Ad-SOD. CsA treatment for two weeks caused a loss of brush border and dilation of proximal tubules, necrosis, and increased leukocyte infiltration into the kidney; these effects were minimized by SOD. Dimethyl sulfoxide (DMSO) was attacked by the hydroxyl radical to produce a methyl radical. Indeed, administration of CsA with 12C-DMSO in rats infected with Ad-lacZ produced a radical adduct with hyperfine coupling constants similar to 4-POBN/methyl radical adduct and another unknown radical adduct. CsA given with 13C-DMSO produced a 12-line spectrum, confirming the involvement of hydroxyl radicals. Free radical adducts detected in urine were increased approximately fivefold by CsA, an effect blocked completely by SOD.

CONCLUSIONS

CsA increases free radical formation. Gene delivery of SOD blocks formation of free radicals, thereby minimizing nephrotoxicity caused by CsA.

Phthalates rapidly increase production of reactive oxygen species in vivo: role of Kupffer cells

The role of oxidants in the mechanism of tumor promotion by peroxisome proliferators remains controversial. The idea that induction of acyl-coenzyme A oxidase leads to increased production of H(2)O(2), which damages DNA, seems unlikely; still, free radicals might be important in signaling in specialized cell types such as Kupffer cells, which produce mitogens. Because hard evidence for increased oxidant production in vivo after treatment with peroxisome proliferators is lacking, the spin-trapping technique and electron spin resonance spectroscopy were used. Rats were given di(2-ethylhexyl) phthalate (DEHP) acutely. The spin trapping agent alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone was also given and bile samples were collected for 4 h. Under these conditions, the intensity of the six-line radical adduct signal increased to a maximum value of 2.5-fold 2 h after administration of DEHP, before peroxisomal oxidases were induced. Furthermore, DEHP given with [(13)C(2)]dimethyl sulfoxide produced a 12-line electron spin resonance spectrum, providing evidence that DEHP stimulates (*)OH radical formation in vivo. Furthermore, when rats were pretreated with dietary glycine, which inactivates Kupffer cells, DEHP did not increase radical signals. Moreover, similar treatments were performed in knockout mice deficient in NADPH oxidase (p47(phox) subunit). Importantly, DEHP increased oxidant production in wild-type but not in NADPH oxidase-deficient mice. These data provide evidence for the hypothesis that the molecular source of free radicals induced by peroxisome proliferators is NADPH oxidase in Kupffer cells. On the contrary, radical adduct formation was not affected in peroxisome proliferator-activated receptor alpha knockout mice. These observations represent the first direct, in vivo evidence that phthalates increase free radicals in liver before peroxisomal oxidases are induced.

Reduced early alcohol-induced liver injury in CD14-deficient mice

Activation of Kupffer cells by gut-derived endotoxin is associated with alcohol-induced liver injury. Recently, it was shown that CD14-deficient mice are more resistant to endotoxin-induced shock than wild-type controls. Therefore, this study was designed to investigate the role of CD14 receptors in early alcohol-induced liver injury using CD14 knockout and wild-type BALB/c mice in a model of enteral ethanol delivery. Animals were given a high-fat liquid diet continuously with ethanol or isocaloric maltose-dextrin as control for 4 wk. The liver to body weight ratio in wild-type mice (5.8 +/- 0.3%) was increased significantly by ethanol (7.3 +/- 0.2%) but was not altered by ethanol in CD14-deficient mice. Ethanol elevated serum alanine aminotransferase levels nearly 3-fold in wild-type mice, but not in CD14-deficient mice. Wild-type and knockout mice given the control high-fat diet had normal liver histology, whereas ethanol caused severe liver injury (steatosis, inflammation, and necrosis; pathology score = 3.8 +/- 0.4). In contrast, CD14-deficient mice given ethanol showed minimal hepatic changes (score = 1.6 +/- 0.3, p < 0.05). Additionally, NF-kappa B, TGF-beta, and TNF-alpha were increased significantly in wild-type mice fed ethanol but not in the CD14 knockout. Thus, chronic ethanol feeding caused more severe liver injury in wild-type than CD14 knockouts, supporting the hypothesis that endotoxin acting via CD14 plays a major role in the development of early alcohol-induced liver injury.

[Luminescence dependence upon concentration and temperature in YPO4:Pr3+]

Under selective excitation 3P0 state of Pr3+ ion in YPO4, the emission spectra and fluorescence decay curves are measured at different concentrations and temperatures. The origin of the spectral line located at 613.2 nm has been discussed and assigned to be the 1D2 (gamma 3)-->3H4 (gamma 5) transition. The different concentration dependence of emission intensities of levels 3P0 and 1D2 has been studied. Using static model, the fluorescence decay curve of 1D2 level is fitted, and the result shows that the cross-relaxation caused by the interaction of dipole-quadrupole between adjacent Pr3+ ions results in the concentration quenching.

A mechanism for the partial insertion of protein kinase C into membranes

We propose that the principle driving force allowing protein kinase C (PKC) to insert partway into membranes is the transient creation of an interior hydrophilic phase within the membrane. We further suggest that this phase is composed of non-bilayer-forming elements, such as diacylglycerol or phorbol esters. We used the combination of fluorescence resonance energy transfer (using fluorescently labeled phospholipid molecules and the endogenous tryptophan residues of PKC) and fluorescence quenching by the water-soluble reagent potassium iodide. The experimental system used micelles and purified PKC. Our model accounts for both the established kinetic data on PKC as well as the physical requirements of protein-membrane interaction. Moreover, it establishes PKC as the first example of a partially embedded membrane protein, and provides a mechanism to account for its activation.

Rare earth elements in naturally grown fern Dicranopteris linearis in relation to their variation in soils in south-Jiangxi region (southern China)

Ferns (Dicranopteris linearis) and soils, sampled from four rare earth mining areas and one non-mining area locating in South-Jiangxi region, were chosen for analysis of 15 rare earth elements (REEs) by inductively coupled plasma-mass spectrometry (ICP-MS). The fern samples were divided into 4 parts: root, stem, petiole, and lamina. The soils of the same sites were also sampled, and 4 soil layers were observed at the profile: A (0-20 cm depth), B (20-150 cm depth), C (150-400 cm depth), and D (rock). The distribution patterns and transportation characteristics of REEs of different soil layers and of different parts of D. linearis were studied. The results showed that in the soil layers, the sigma REE (the sum of the concentrations of 15 REEs) of A layer, as well as B layer were lower than that of C layer, but Ce was relatively concentrated in A layer. The sigma REE of different parts of D. linearis were lamina, root > stem > petiole. The REE distribution patterns of D. linearis root were similar to the total REE distribution patterns of the A layer of their host soils, especially to the soluble REE distribution patterns of the A layer of their host soils. The REEs were fractionated in their transportation in D. linearis. The abundances of heavy rare earth elements (HREEs, Gd to Lu and Y) in the stem, petiole, lamina are lower than those in the root.

[A preliminary study on the incidence of cedar pollinosis in district of Wuhan]

OBJECTIVE

To investigate the incidence of cedar pollinosis in district of Wuhan.

METHOD

A survey relative to cedar pollinosis was carried out in 309 students in Hubei Medical University in 1999, including questionnaire investigation, nasal inspection and scratch test. From February to April of 2000, a clinical investigation of cedar pollinosis was adopted among 205 patients of allergic rhinitis including scratch test and nasal mucosa test.

RESULT

1. The positive rate of cedar pollen scratch test of 309 students was 7.8%. 2. 59 cases (28.8%) was hypersensitive to cedar pollen clinically in allergen test.

CONCLUSION

Cedar pollinosis is one kind of important pollinosis in district of Wuhan and should be paid high attention to.

NADPH oxidase-derived free radicals are key oxidants in alcohol-induced liver disease

In North America, liver disease due to alcohol consumption is an important cause of death in adults, although its pathogenesis remains obscure. Despite the fact that resident hepatic macrophages are known to contribute to early alcohol-induced liver injury via oxidative stress, the exact source of free radicals has remained a mystery. To test the hypothesis that NADPH oxidase is the major source of oxidants due to ethanol, we used p47(phox) knockout mice, which lack a critical subunit of this major source of reactive oxygen species in activated phagocytes. Mice were treated with ethanol chronically, using a Tsukamoto-French protocol, for 4 weeks. In wild-type mice, ethanol caused severe liver injury via a mechanism involving gut-derived endotoxin, CD14 receptor, production of electron spin resonance-detectable free radicals, activation of the transcription factor NF-kappaB, and release of cytotoxic TNF-alpha from activated Kupffer cells. In NADPH oxidase-deficient mice, neither an increase in free radical production, activation of NF-kappaB, an increase in TNF-alpha mRNA, nor liver pathology was observed. These data strongly support the hypothesis that free radicals from NADPH oxidase in hepatic Kupffer cells play a predominant role in the pathogenesis of early alcohol-induced hepatitis by activating NF-kappaB, which activates production of cytotoxic TNF-alpha.

Hypotaurine, N-methyltaurine, taurine, and glycine betaine as dominant osmolytes of vestimentiferan tubeworms from hydrothermal vents and cold seeps

Organic osmolytes, solutes that regulate cell volume, occur at high levels in marine invertebrates. These are mostly free amino acids such as taurine, which are "compatible" with cell macromolecules, and methylamines such as trimethylamine oxide, which may have a nonosmotic role as a protein stabilizer, and which is higher in many deep-sea animals. To better understand nonosmotic roles of osmolytes, we used high-performance liquid chromatography and (1)H-nuclear magnetic resonance (NMR) to analyze vestimentiferans (vestimentum tissue) from unusual marine habitats. Species from deep hydrothermal vents were Riftia pachyptila of the East Pacific Rise (2,636 m) and Ridgeia piscesae of the Juan de Fuca Ridge (2,200 m). Species from cold hydrocarbon seeps were Lamellibrachia sp. and an unnamed escarpid species from subtidal sediment seeps (540 m) off Louisiana and Lamellibrachia barhami from bathyal tectonic seeps (1,800-2,000 m) off Oregon. Riftia were dominated by hypotaurine (152 mmol/kg wet wt), an antioxidant, and an unidentified solute with an NMR spectrum consistent with a methylamine. Ridgeia were dominated by betaine (N-trimethylglycine; 109 mmol/kg), hypotaurine (64 mmol/kg), and taurine (61 mmol/kg). The escarpids were dominated by taurine (138 mmol/kg) and hypotaurine (69 mmol/kg). Both Lamellibrachia populations were dominated by N-methyltaurine (209-252 mmol/kg), not previously reported as a major osmolyte, which may be involved in methane and sulfate metabolism. Trunk and plume tissue of the Oregon Lamellibrachia were nearly identical to vestimentum in osmolyte composition. The methylamines may also stabilize proteins against pressure; they were significantly higher in the three deeper-dwelling groups.

Effects of SSM (specific substance maruyama) on HBe antigen-positive chronic hepatitis B -clinical efficacy and modulation of cytokines

Twenty-three patients with HBe antigen-positive chronic hepatitis B were treated with capitalite first letters Maruyama (SSM). HBe antigen turned negative in 15 patients. The levels of various cytokines in pre- and post-treatment frozen serum samples from six patients whose HBe antigen turned negative and from five whose HBe antigen did not were examined. Reduction of serum interleukin (IL) -10 level to below 20 pg/ml was observed after SSM treatment in four of the six patients whose HBe antigen turned negative. SSM was found to stimulate the production of interferon (IFN) -gamma in peripheral blood cells from two healthy volunteers. This stimulatory effect was confirmed in 12 out of 24 healthy volunteers. SSM augmented the production of IFN-gamma in eight out of 10 patients with chronic hepatitis B and nine of 10 with hepatitis C. These results demonstrate for the first time that SSM stimulates the production of IFN-gamma in human peripheral blood cells and also suggest that treatment of HBe antigen-positive chronic hepatitis B patients with SSM leads to the clearance of HBe antigen and normalization of serum aspartate aminotransferase levels through inhibition of IL-10 and stimulation of IFN-gamma.

Individual and combined antioxidant effects of seven phenolic agents in human erythrocyte membrane ghosts and phosphatidylcholine liposome systems: importance of the partition coefficient

Antioxidant activities of seven phenolic agents against Fe(2+)-induced lipid oxidation were compared with alpha-tocopherol, beta-carotene, and vitamin C in human erythrocyte membrane ghosts and liposome systems. The antioxidant activity of five test flavonoids followed the order catechin > epicatechin > rutin > quercetin > myricetin in both systems (p < 0.05), which was negatively correlated with their partition coefficients. The antioxidant interaction of these phenolic agents with alpha-tocopherol, beta-carotene, or vitamin C in inhibiting Fe(2+)-induced lipid oxidation was examined. Synergistic effects were present in the combinations of alpha-tocopherol plus caffeic acid, catechin, or epicatechin as well as in all combinations of vitamin C plus phenolic antioxidants. On the basis of the stronger individual and combined effects present in caffeic acid, catechin, and epicatechin, the application of these three phenolic agents with or without alpha-tocopherol, beta-carotene, and vitamin C may provide stronger protective benefits against lipid oxidation, which may be helpful for oxidation-related diseases prevention.

Effects of cytomegalovirus infection and prolonged cold ischemia on chronic rejection of rat renal allografts

Previous studies have demonstrated that both cytomegalovirus (CMV) infection and prolonged cold ischemia of the allograft (CI) are associated with chronic rejection of renal transplants. The purpose of this study is to investigate the effect of CMV infection, of CI and of the combination of both, on the progression of chronic rejection, and to obtain a more detailed insight in their effects on the expression of adhesion molecules. Therefore, a rat transplantation model was used. Lewis recipients of renal allografts (with and without CI) from MHC-incompatible Brown Norway rats were inoculated with rat CMV or left uninfected. CMV infection alone resulted in an increased influx of CD4+ cells and macrophages early after infection, and in an increase in glomerular sclerosis and intima proliferation. CI caused an increase in infiltrating NK cells and an effect on intimal proliferation, glomerular sclerosis, and tubular atrophy. When CMV infection and CI were combined, an additive effect could be measured. This was however not the case for the function of the kidney. The creatinin showed a synergistic effect of the two influencing factors. Due to the CMV infection, an increase in CD49d cells was detected. CI resulted in an increase in CD18 cells and an increase in the expression of CD62P on vessels, and CD54 and CD44 on tubules. When CMV infection and CI were combined, all the effects caused by CMV and CI alone were present in an additional way. The results of the present study suggest that special attention should be paid to the recipient of an ischemically injured graft when either the donor or the recipient is CMV-infected. The patterns seen in histology, the infiltration of leukocytes and the expression of adhesion molecules, suggest that CI and CMV infection both have an effect on rejection, but act by different mechanisms.

Inhibition of chronic rejection of aortic allografts by dietary glycine

BACKGROUND

Chronic rejection is influenced by a variety of risk factors, including histoincompatibility and ischemia. Glycine, a cytoprotective agent, has been shown to protect against ischemia-reperfusion injury in the liver, inactivate hepatic resident macrophages, minimize cyclosporin A-induced nephrotoxicity, and exhibit immunosuppressive properties in vitro. The aim of this study was to investigate whether dietary glycine could reduce development of chronic rejection.

METHODS

Lewis recipients of Fisher-344 abdominal aortic allografts received diets that contained either 5% glycine plus 15% casein or 20% casein as control for 10 weeks. Vascular lesions of aortic isografts and allografts were evaluated quantitatively with image analysis and cell counting.

RESULTS

No significant vascular changes were observed in isografts (mean medial areas of 3.3 +/- 0.3x0(5) microm2). However, dramatic intimal thickening (neointimal area 2.1+/-0.3) and medial thinning (1.5+/-0.3) were observed in allografts from rats fed control diet. In contrast, glycine significantly reduced the neointima by 45% (1.2+/-0.3) and protected the media (3.5+/-0.2). This led to intima to media area ratios almost twice as large in the control group as in glycine-fed rats (2.2+/-0.4 vs. 1.1+/-0.3, P<0.05). Moreover, infiltrating leukocytes, especially macrophages, were reduced significantly in the adventitia by glycine. In addition, glycine inhibited proliferation and migration of rat aortic smooth muscle cells in culture by 45 and 60%, respectively.

CONCLUSION

These results indicate that dietary glycine minimizes histopathological changes of chronic rejection by reducing the immune response and, in part, by minimizing proliferation and migration of smooth muscle cells.

Directed actin polymerization is the driving force for epithelial cell-cell adhesion

We have found that epithelial cells engage in a process of cadherin-mediated intercellular adhesion that utilizes calcium and actin polymerization in unexpected ways. Calcium stimulates filopodia, which penetrate and embed into neighboring cells. E-cadherin complexes cluster at filopodia tips, generating a two-rowed zipper of embedded puncta. Opposing cell surfaces are clamped by desmosomes, while vinculin, zyxin, VASP, and Mena are recruited to adhesion zippers by a mechanism that requires alpha-catenin. Actin reorganizes and polymerizes to merge puncta into a single row and seal cell borders. In keratinocytes either null for alpha-catenin or blocked in VASP/Mena function, filopodia embed, but actin reorganization/polymerization is prevented, and membranes cannot seal. Taken together, a dynamic mechanism for intercellular adhesion is unveiled involving calcium-activated filopodia penetration and VASP/Mena-dependent actin reorganization/polymerization.

CYP2E1 is not involved in early alcohol-induced liver injury

The continuous intragastric enteral feeding protocol in the rat was a major development in alcohol-induced liver injury (ALI) research. Much of what has been learned to date involves inhibitors or nutritional manipulations that may not be specific. Knockout technology avoids these potential problems. Therefore, we used long-term intragastric cannulation in mice to study early ALI. Reactive oxygen species are involved in mechanisms of early ALI; however, their key source remains unclear. Cytochrome P-450 (CYP)2E1 is induced predominantly in hepatocytes by ethanol and could be one source of reactive oxygen species leading to liver injury. We aimed to determine if CYP2E1 was involved in ALI by adapting the enteral alcohol (EA) feeding model to CYP2E1 knockout (-/-) mice. Female CYP2E1 wild-type (+/+) or -/- mice were given a high-fat liquid diet with either ethanol or isocaloric maltose-dextrin as control continuously for 4 wk. All mice gained weight steadily over 4 wk, and there were no significant differences between groups. There were also no differences in ethanol elimination rates between CYP2E1 +/+ and -/- mice after acute ethanol administration to naive mice or mice receiving EA for 4 wk. However, EA stimulated rates 1.4-fold in both groups. EA elevated serum aspartate aminotransferase levels threefold to similar levels over control in both CYP2E1 +/+ and -/- mice. Liver histology was normal in control groups. In contrast, mice given ethanol developed mild steatosis, slight inflammation, and necrosis; however, there were no differences between the CYP2E1 +/+ and -/- groups. Chronic EA induced other CYP families (CYP3A, CYP2A12, CYP1A, and CYP2B) to the same extent in CYP2E1 +/+ and -/- mice. Furthermore, POBN radical adducts were also similar in both groups. Data presented here are consistent with the hypothesis that oxidants from CYP2E1 play only a small role in mechanisms of early ALI in mice. Moreover, this new mouse model illustrates the utility of knockout technology in ALI research.

[Studies on gene mutation and micronucleus formation induced by ethylnitrosourea (ENU) in transgenic mice in vivo]

OBJECTIVE

To determine the feasibility of using pUC 118NX plasmid-based transgenic mice in the study of induced mutation in vivo with known mutagen, ethylnitrosourea (ENU).

METHODS

pUC 118NX plasmid was recovered from the spleen genomic DNA of ENU-treated and untreated xylE, C57BL/6J transgenic mice with enzyme digestion and circularizing. The recovered pUC 118NX plasmid was electroporated into DH10B host cells, which were incubated in LB solid medium containing proper ampicillin overnight and then sprayed with catechol solution. Mutant could be detected by difference in yellow and white color of the stains and its xylE target gene could be sequenced for further identifying its mutation type. In addition, peripheral blood and bone marrow cells were isolated from xylE, C57BL/6J transgenic mice and micronucleus frequency (MNF) induced by ENU was observed.

RESULTS

The spontaneous mutant frequency for xylE gene in the spleen of xylE, C57BL/6J transgenic mice was less than 4.79 x 10(-5), significantly different from that treated with ENU (50 mg/kg), 19.83 x 10(-5). Types of gene mutation induced by ENU in the spleen of xylE, C57BL/6J transgenic mice included transversion (50%), one or two-base insertion (37.5%) and transition (12.5%). MNF in peripheral blood normochromatic erythrocyte (NCE) and in bone marrow polychromatic erythrocyte (PCE) of ENU-treated (50 mg/kg x 5) mice were 7.6 per thousand and 8.8 per thousand, respectively, both significantly different from the controls treated with solvent (P < 0.01). It indicated that chromosome aberration could be induced by ENU.

CONCLUSION

The pUC118NX plasmid-based xylE, C57BL/6J transgenic mice, which could be used in detecting gene mutation and chromosome aberration in vivo simultaneously, provided a novel detection system for overall assessment of genetic toxicity of chemicals.

Estrogen is involved in early alcohol-induced liver injury in a rat enteral feeding model

The aim of this study was to investigate whether reduction in blood estrogen by removal of the ovaries would decrease the sensitivity of female rats to early alcohol-induced liver injury using an enteral ethanol feeding model, and if so, whether estrogen replacement would compensate. Livers from ovariectomized rats with or without estrogen replacement after 4 weeks of continuous ethanol exposure were compared with nonovariectomized rats in the presence or absence of ethanol. Ethanol increased serum alanine transaminase (ALT) levels from 30 +/- 6 to 64 +/- 7 U/L. This effect was blocked by ovariectomy (31 +/- 7) and totally reversed by estrogen replacement (110 +/- 23). Ethanol increased liver weight and fat accumulation, an effect that was minimized by ovariectomy and reversed partially by estrogen replacement. Infiltrating leukocytes were increased 6. 7-fold by ethanol, an effect that was blunted significantly by ovariectomy and reversed by estrogen replacement. Likewise, a similar pattern of changes was observed in the number of necrotic hepatocytes. Blood endotoxin and hepatic levels of CD14 messenger RNA (mRNA) and protein were increased by ethanol. This effect was blocked in ovariectomized rats and elevated by estrogen replacement. Moreover, Kupffer cells isolated from ethanol-treated rats with estrogen replacement produced more tumor necrosis factor alpha (TNF-alpha) than those from control and ovariectomized rats. It is concluded, therefore, that the sensitivity of rat liver to alcohol-induced injury is directly related to estrogen, which increases endotoxin in the blood and CD14 expression in the liver, leading to increased TNF-alpha production.

Glycine: a new anti-inflammatory immunonutrient

The mechanism of the immunosuppressive effects of glycine and its pathophysiological applications are discussed in this review. Glycine has been well characterized in spinal cord as an inhibitory neurotransmitter which activates a glycine-gated chloride channel (GlyR) expressed in postsynaptic membranes. Activation of the channel allows the influx of chloride, preventing depolarization of the plasma membrane and the potentiation of excitatory signals along the axon. Glycine has recently been shown to have similar inhibitory effects on several white blood cells, including hepatic and alveolar macrophages, neutrophils, and lymphocytes. Pharmacological analysis using a GlyR antagonist strychnine, chloride-free buffer, and radiolabeled chloride has provided convincing evidence to support the hypothesis that many white blood cells contain a glycine-gated chloride channel with properties similar to the spinal cord GlyR. Molecular analysis using reverse transcription-polymerase chain reaction and Western blotting has identified the mRNA and protein for the beta subunit of the GlyR in total RNA and purified membrane protein from rat Kupffer cells. Dietary glycine is protective in rat models against endotoxemia, liver ischemia-reperfusion, and liver transplantation, most likely by inactivating the Kupffer cell via this newly identified glycine-gated chloride channel. Glycine also prevents the growth of B 16 melanomas cell in vivo. Moreover, dietary glycine is protective in the kidney against cyclosporin A toxicity and ischemia-reperfusion injury. Glycine may be useful clinically for the treatment of sepsis, adult respiratory distress syndrome, arthritis, and other diseases with an inflammatory component.

[Epidemiological survey on orchard pollinosis]

OBJECTIVE

To investigate the prevalence of Orchard Pollinosis in China.

METHOD

From 1995 to 1998, an epidemiological survey on orchard pollinosis was carried on among 1,660 primary and middle school students and 2,167 university students, including questionnaire investigation, nasal inspection and scratch test. From April to June of 1998, a clinical investigation of orchard pollinosis was adopted among 30 patients of allergic rhinitis including scratch test and nasal mucosa test.

RESULT

1. The total positive rate of orchard pollen scratch test was 6.7%, and the prevalence of orchard pollinosis was 0.37%. 2. 5 cases (16.7%) were hypersensitive to orchard pollen clinically in allergen test.

CONCLUSION

Orchard pollinosis is one kind of important pollinosis and should be paid high attention to.

Transforming growth factor beta1 enhances platelet aggregation through a non-transcriptional effect on the fibrinogen receptor

Upon activation, platelets store and release large amounts of the peptide transforming growth factor beta1 (TGFbeta1). The released TGFbeta1 can then act on nearby vascular cells to mediate subsequent vessel repair. In addition, TGFbeta1 may circulate to bone marrow and regulate megakaryocyte activity. It is not known what effect, if any, TGFbeta1 has on platelets. Adult TGFbeta1-deficient mice exhibit thrombocythemia and a mild bleeding disorder that is shown to result from faulty platelet aggregation. TGFbeta1-deficient platelets are shown to contain functional receptors, and preincubation with recombinant TGFbeta1 improves aggregation, demonstrating that TGFbeta1 plays an active role in platelet aggregation. TGFbeta1-deficient platelets fail to retain bound fibrinogen in response to aggregation agonists, but they possess normal levels of the alpha(IIb)/beta(3) fibrinogen receptor. Signaling from agonist receptors is normal because the platelets change shape, produce thromboxane A(2), and present P-selectin in response to stimulation. Consequently, activation and maintenance of alpha(IIb)/beta(3) into a fibrinogen-binding conformation is impaired in the absence of TGFbeta1. 4-Phorbol 12-myristate 13-acetate treatment and protein kinase C activity measurements suggest a defect downstream of protein kinase C in its activation cascade. Because platelets lack nuclei, these data demonstrate for the first time a non-transcriptionally mediated TGFbeta1 signaling pathway that enhances the activation and maintenance of integrin function.

Essential role of tumor necrosis factor alpha in alcohol-induced liver injury in mice

BACKGROUND & AIMS

Tumor necrosis factor (TNF)-alpha is associated with increased mortality in alcoholics, but its role in early alcohol-induced liver injury is not fully understood. Recently, it was shown that injury induced by the enteral alcohol delivery model of Tsukamoto and French was reduced by antibodies to TNF-alpha. To obtain clear evidence for or against the hypothesis that TNF-alpha is involved, we studied TNF receptor 1 (TNF-R1, p55) or 2 (TNF-R2, p75) knockout mice.

METHODS

Long-term enteral alcohol delivery was modified for male gene-targeted mice lacking TNF-R1 and TNF-R2. Animals were given a high-fat liquid diet continuously with either ethanol or isocaloric maltose-dextrin as a control for 4 weeks.

RESULTS

Ethanol elevated serum levels of alanine aminotransferase nearly 3-fold in wild-type and TNF-R2 knockout mice but not in TNF-R1 knockout mice. Likewise, ethanol caused severe liver injury in wild-type mice (pathology score, 5.5 +/- 0.6) and TNF-R2 knockout mice (pathology score, 5.0 +/- 0.4), but not in TNF-R1 knockout mice (pathology score, 0.8 +/- 0.4; P < 0.001).

CONCLUSIONS

Long-term ethanol feeding caused liver injury in wild-type and TNF-R2 knockout mice but not in TNF-R1 knockout mice, providing solid evidence in support of the hypothesis that TNF-alpha plays an important role in the development of early alcohol-induced liver injury via the TNF-R1 pathway. Moreover, the long-term enteral ethanol feeding technique we described for the first time for knockout mice provides a useful new tool for alcohol research.

Essential role of tumor necrosis factor alpha in alcohol-induced liver injury in mice

BACKGROUND & AIMS

Tumor necrosis factor (TNF)-alpha is associated with increased mortality in alcoholics, but its role in early alcohol-induced liver injury is not fully understood. Recently, it was shown that injury induced by the enteral alcohol delivery model of Tsukamoto and French was reduced by antibodies to TNF-alpha. To obtain clear evidence for or against the hypothesis that TNF-alpha is involved, we studied TNF receptor 1 (TNF-R1, p55) or 2 (TNF-R2, p75) knockout mice.

METHODS

Long-term enteral alcohol delivery was modified for male gene-targeted mice lacking TNF-R1 and TNF-R2. Animals were given a high-fat liquid diet continuously with either ethanol or isocaloric maltose-dextrin as a control for 4 weeks.

RESULTS

Ethanol elevated serum levels of alanine aminotransferase nearly 3-fold in wild-type and TNF-R2 knockout mice but not in TNF-R1 knockout mice. Likewise, ethanol caused severe liver injury in wild-type mice (pathology score, 5.5 +/- 0.6) and TNF-R2 knockout mice (pathology score, 5.0 +/- 0.4), but not in TNF-R1 knockout mice (pathology score, 0.8 +/- 0.4; P < 0.001).

CONCLUSIONS

Long-term ethanol feeding caused liver injury in wild-type and TNF-R2 knockout mice but not in TNF-R1 knockout mice, providing solid evidence in support of the hypothesis that TNF-alpha plays an important role in the development of early alcohol-induced liver injury via the TNF-R1 pathway. Moreover, the long-term enteral ethanol feeding technique we described for the first time for knockout mice provides a useful new tool for alcohol research.

[Inhibitory effects of recombinant human neurotrophin-4/5 protein on neurotoxicity caused by arsenic trioxide]

OBJECTIVE

To study preliminarily the inhibitory effects of recombinant human neurotrophin (hNT)-4/5 protein on neurotoxicity caused by arsenic trioxide (As(2)O(3)).

METHODS

Nerve cells of the chicken embryonic forebrain and PC12 cells were co-cultured with recombinant hNT-4/5 protein and As(2)O(3) (0 - 16 micromol/L) for 24 and 48 hours, respectively, to observe the survival of nerve cells and the outgrowth of PC12 cells, with clone expression and recombination techniques.

RESULTS

There was significant difference in survival rate of nerve cells between the experimental and control groups (P < 0.01) after co-culture for 48 hours, and survival rate and number of neuron outgrowth increased with the concentration of hNT-4/5 protein.

CONCLUSION

Recombinant hNT-4/5 protein could inhibit neurotoxicity caused by As(2)O(3), which provided a basis to find an anti-toxic factor in the environment by genetic engineering.

Dietary glycine and renal denervation prevents cyclosporin A-induced hydroxyl radical production in rat kidney

Cyclosporin A (CsA) nephrotoxicity is associated with renal hypoxia and increases in free radicals in the urine. This study was designed to elucidate the mechanism of radical production caused by CsA. Pretreatment of rats with CsA (25 mg/kg, i.g.) for 5 days decreased glomerular filtration rates by 65%, an effect largely prevented by both dietary glycine (5%) or renal denervation. CsA dissolved in olive oil produced a 6-line alpha-(4-pyridyl 1-oxide)-N-tert-butylnitrone (4-POBN)/free radical signal in the urine, which partitioned predominantly into the aqueous phase after chloroform extraction (i.e., it is water soluble). Dimethyl sulfoxide (DMSO) is attacked by the hydroxyl radical to produce a methyl radical; administration of CsA with [(12)C]DMSO produced two radical species in urine, one with hyperfine coupling constants similar to the 4-POBN/methyl radical adduct found in aqueous solution. CsA given with [(13)C]DMSO produced a 12-line spectrum, confirming the formation of hydroxyl radicals. The methyl radical produced by the hydroxyl radical represented 62% of radicals detected in urine but only 15% in bile. Therefore, hydroxyl radicals are produced largely in the kidney. Free radicals in urine were increased about 5-fold by CsA, an effect completely blocked by the inhibitory neurotransmitter, glycine, or by renal denervation. CsA infusion for 30 min increased efferent renal nerve activity 2-fold, and dietary glycine (5%) totally blocked this phenomenon. Taken together, these data are consistent with the hypothesis that CsA increases hydroxyl radical formation by increasing renal nerve activity resulting in vasoconstriction and hypoxia-reoxygenation. Glycine blunts the effect of CsA on the renal nerve, which explains, in part, prevention of nephrotoxicity.

New techniques for DNA sequence classification

DNA sequence classification is the activity of determining whether or not an unlabeled sequence S belongs to an existing class C. This paper proposes two new techniques for DNA sequence classification. The first technique works by comparing the unlabeled sequence S with a group of active motifs discovered from the elements of C and by distinction with elements outside of C. The second technique generates and matches gapped fingerprints of S with elements of C. Experimental results obtained by running these algorithms on long and well conserved Alu sequences demonstrate the good performance of the presented methods compared with FASTA. When applied to less conserved and relatively short functional sites such as splice-junctions, a variation of the second technique combining fingerprinting with consensus sequence analysis gives better results than the current classifiers employing text compression and machine learning algorithms.

[Clinical manifestations and CT diagnosis of non-allergic fungal sinusitis]

OBJECTIVE

The diagnose of fungal sinusitis, especially complicated by bone destructive, and its differential diagnosis from malignant tumour of nasal sinus were studied.

METHOD

Five cases were diagnosed with CT; nasal sinus microsurgery was done in 4 cases and sinusotomy in one case. None of them were treated by antifungal agents.

RESULT

Fungal filaments were postoperatively shown in 5 pathological reports, fungal spores in some cases. No recurrence and complications occurred as followed from 6 months to 3 years.

CONCLUSION

It is not easy to differentiate fungal sinusitis from malignant tumour of nasal sinus, sometimes, but CT has demonstrated its importance of diagnostic value.

Time lines and computer-based visual editing: new techniques for assessing exposure in epidemiologic studies

We describe a time-line-based methodology for collecting exposure data for epidemiologic studies and for processing these data for statistical analysis with readily available software for the personal computer. The four components to this approach are: (1) collecting data in a memory-enhancing time-line format; (2) entering data from time lines into a computer database and editing them; (3) making a quantitative estimate of exposure, intake, or dose for each exposure event; and (4) creating analysis datasets by 'slicing' the quantified time lines based on desired exposure intervals or disease latent periods. Compared with fixed-format interviews, time-line-based interviews help subjects organize remembered events, thereby reducing confusion. They do not restrict responses to predetermined categorical exposure responses. The time-line methodology also facilitates the collection of supplementary data necessary for computing doses for complex exposures and the packaging of quantified exposures into analysis datasets for any time period of interest.

[Development of plasmid-based transgenic mice carrying with target gene xylE]

OBJECTIVE

To develop a transgenic mouse model carrying with plasmid pUC118NX integrated into its genomic DNA for detecting mutagenesis.

METHODS

DNA of plasmid UC118NX in target gene xy1E was injected microscopically into male protonucleus of 376 mouse spermatova, and 225 survival spermatova were transferred into the oviducts in both sides of 11 pseudopregnant female mice to develop their offspring. The genomic DNA in survival young mice were analyzed with polymerase chain reaction (PCR)-Southern blot, plasmid transformation test and endonuclease-digestion.

RESULTS

Seven pseudopregnant mice got pregnant, and 29 offspring were delivered and 25 survived of which 18 were identified with positive for PCR-Southern blot (72%). The two stout male mice with intact integration of plasmid pUC118NX in their genome were finally chosen as founders to detect gene mutation in vivo and establish transgenic mouse lineages.

CONCLUSION

Transgenic C57BL/6J mice integrated with plasmid pUC118NX into their genomic DNA have been successfully developed.

Desmoplakin is required early in development for assembly of desmosomes and cytoskeletal linkage

Desmosomes first assemble in the E3.5 mouse trophectoderm, concomitant with establishment of epithelial polarity and appearance of a blastocoel cavity. Throughout development, they increase in size and number and are especially abundant in epidermis and heart muscle. Desmosomes mediate cell-cell adhesion through desmosomal cadherins, which differ from classical cadherins in their attachments to intermediate filaments (IFs), rather than actin filaments. Of the proteins implicated in making this IF connection, only desmoplakin (DP) is both exclusive to and ubiquitous among desmosomes. To explore its function and importance to tissue integrity, we ablated the desmoplakin gene. Homozygous -/- mutant embryos proceeded through implantation, but did not survive beyond E6.5. Surprisingly, analysis of these embryos revealed a critical role for desmoplakin not only in anchoring IFs to desmosomes, but also in desmosome assembly and/or stabilization. This finding not only unveiled a new function for desmoplakin, but also provided the first opportunity to explore desmosome function during embryogenesis. While a blastocoel cavity formed and epithelial cell polarity was at least partially established in the DP (-/-) embryos, the paucity of desmosomal cell-cell junctions severely affected the modeling of tissue architecture and shaping of the early embryo.

Effects of chronic ethanol consumption on cytokine regulation of liver regeneration

Ethanol ingestion may interrupt the proregenerative signal transduction that is initiated by injury-related cytokines such as tumor necrosis factor (TNF)-alpha and TNF-alpha- inducible cytokines including interleukin (IL)-6. To test this theory, liver regeneration, TNF-alpha and IL-6 expression, and cytokine-regulated prereplicative events were compared in ethanol-fed rats and isocalorically fed controls after 70% partial hepatectomy (PH). Ethanol feeding inhibits hepatocyte replication and recovery of liver mass after PH but generally promotes induction of both cytokines in the liver and extrahepatic tissues (i.e., white adipose tissue). Cytokine-regulated events that occur early in the prereplicative period are influenced differentially. TNF-alpha-dependent increases in hepatic nuclear factor-kappaB (NF-kappaB) p50 and p65 expression and DNA binding activity are prevented, whereas IL-6-dependent inductions of hepatic Stat-3 phosphorylation and DNA binding activity occur normally. In contrast, events (e.g., induction of cyclin D1, cdk-1, cyclin D3, and p53 mRNA) that occur at the end of the prereplicative period are uniformly inhibited. These findings indicate that chronic ethanol ingestion arrests the regenerative process during the prereplicative period and demonstrate that increased TNF-alpha, IL-6 and Stat-3 are not sufficient to assure hepatocyte proliferation after PH.

Cyclosporin A increases hypoxia and free radical production in rat kidneys: prevention by dietary glycine

The major side effect of cyclosporin A is severe nephrotoxicity. It is likely that cyclosporin A causes vasoconstriction leading to hypoxia-reperfusion injury; therefore, these experiments were designed to attempt to obtain physical evidence for hypoxia and free radical production in kidney following cyclosporin A. Rats were treated daily with cyclosporin A (25 mg/kg ig) for 5 days, and pimonidazole, a hypoxia marker, was injected 2 h after the last dose of cyclosporin A. A dose of alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN) was injected 3 h after cyclosporin A to trap free radicals. Cyclosporin A doubled serum creatinine and decreased glomerular filtration rates by 65% as expected. Pimonidazole adduct binding in the kidney was increased nearly threefold by cyclosporin A, providing physical evidence for tissue hypoxia. Moreover, cyclosporin A increased 4-POBN/radical adducts nearly sixfold in the urine but did not alter levels in the serum. Glycine, which causes vasodilatation and prevents cyclosporin A toxicity, minimized hypoxia and blocked free radical production; however, it did not alter cyclosporin A blood levels. These results demonstrate for the first time that cyclosporin A causes hypoxia and increases production of a new free radical species exclusively in the kidney. Therefore, it is concluded that cyclosporin A causes renal injury by mechanisms involving hypoxia-reoxygenation, effects which can be prevented effectively by dietary glycine.

The role of gut-derived bacterial toxins and free radicals in alcohol-induced liver injury

Previous research from this laboratory using a continuous enteral ethanol (EtOH) administration model demonstrated that Kupffer cells are pivotal in the development of EtOH-induced liver injury. When Kupffer cells were destroyed using gadolinium chloride (GdCl3) or the gut was sterilized with polymyxin B and neomycin, early inflammation due to EtOH was blocked. Anti-tumour necrosis factor (TNF)-alpha antibody markedly decreased EtOH-induced liver injury and increased TNF-mRNA. These findings led to the hypothesis that EtOH-induced liver injury involves increases in circulating endotoxin leading to activation of Kupffer cells. Pimonidazole, a nitro-imidazole marker, was used to detect hypoxia in downstream pericentral regions of the lobule. Following one large dose of EtOH or chronic enteral EtOH for 1 month, pimonidazole binding was increased significantly in pericentral regions of the liver lobule, which was diminished with GdCl3. Enteral EtOH increased free radical generation detected with electron spin resonance (ESR). These radical species had coupling constants matching alpha-hydroxyethyl radical and were shown conclusively to arise from EtOH based on a doubling of the ESR lines when 13C-EtOH was given. Alpha-hydroxyethyl radical production was also blocked by the destruction of Kupffer cells with GdCl3. It is known that females develop more severe EtOH-induced liver injury more rapidly and with less EtOH than males. Female rats on the enteral protocol exhibited more rapid injury and more widespread fatty changes over a larger portion of the liver lobule than males. Plasma endotoxin, ICAM-1, free radical adducts, infiltrating neutrophils and transcription factor NFkappaB were approximately two-fold greater in livers from females than males after 4 weeks of enteral EtOH treatment. Furthermore, oestrogen treatment increased the sensitivity of Kupffer cells to endotoxin. These data are consistent with the hypothesis that Kupffer cells participate in important gender differences in liver injury caused by ethanol.

Human SLUG gene organization, expression, and chromosome map location on 8q

SLUG is a member of the snail family of zinc finger proteins. It is involved in epithelial to mesenchyme cell transition during neurulation and plays a role in limb bud development. We have isolated and described the human SLUG gene by sequencing a region spanning 4034 bp. The human SLUG gene contains three exons. The SLUG transcript is 2.2 kb and is found in placenta and adult heart, pancreas, liver, kidney, and skeletal muscle, and it codes for a protein of 268 amino acids and 29.989 kDa. This protein contains five zinc finger regions. The human SLUG protein is 95, 93, and 88% homologous to mouse, chicken, and Xenopus slug, respectively, but shows only 47% homology to mouse Snail. The zinc finger region is 100% identical between human and mouse Slug. Slug maps to the long arm of chromosome 8, closely linked to D8S2090 between D8S519 and D8S1098.

Glycine accelerates recovery from alcohol-induced liver injury

Glycine prevents hepatic damage caused by hypoxia-reoxygenation, diminishes mortality due to endotoxin and minimizes alcoholic liver injury by decreasing blood ethanol. Our purpose was to investigate the effect of dietary glycine during recovery from early alcohol-induced injury, using a model that mimics the clinical presentation and histopathology with alcoholics. Male Wistar rats were exposed to ethanol continuously for 6 wk via intragastric feeding that resulted in typical histology of alcoholic liver injury, including steatosis, inflammation, necrosis and increased serum levels of aspartate aminotransferase and alanine aminotransferase. After cessation of ethanol, one group of rats received a control diet, the other a glycine-containing diet for 2 wk. During this period, all parameters studied tended to return to baseline values. However, serum aspartate aminotransferase and alanine aminotransferase recovered about 30% more rapidly in rats fed glycine. Further, the hepatic pathology score was also significantly lower in the glycine group than in controls (0.5 vs. 2.6). After 1 wk, steatosis was reduced significantly more in the glycine group (5. 6%) than in controls (8.9%). Glycine also diminished numbers of infiltrating leukocytes and necrotic cells significantly more than in controls. This beneficial effect of glycine may be partly explained by the fact that glycine increased influx of chloride into Kupffer cells leading to diminished tumor necrosis factor-alpha production. These results indicate that a glycine containing diet expedites the process of recovery from ethanol-induced liver injury and may lead to its clinical application in alcoholic hepatitis.

Genetic heterogeneity of Saethre-Chotzen syndrome, due to TWIST and FGFR mutations

Thirty-two unrelated patients with features of Saethre-Chotzen syndrome, a common autosomal dominant condition of craniosynostosis and limb anomalies, were screened for mutations in TWIST, FGFR2, and FGFR3. Nine novel and three recurrent TWIST mutations were found in 12 families. Seven families were found to have the FGFR3 P250R mutation, and one individual was found to have an FGFR2 VV269-270 deletion. To date, our detection rate for TWIST or FGFR mutations is 68% in our Saethre-Chotzen syndrome patients, including our five patients elsewhere reported with TWIST mutations. More than 35 different TWIST mutations are now known in the literature. The most common phenotypic features, present in more than a third of our patients with TWIST mutations, are coronal synostosis, brachycephaly, low frontal hairline, facial asymmetry, ptosis, hypertelorism, broad great toes, and clinodactyly. Significant intra- and interfamilial phenotypic variability is present for either TWIST mutations or FGFR mutations. The overlap in clinical features and the presence, in the same genes, of mutations for more than one craniosynostotic condition-such as Saethre-Chotzen, Crouzon, and Pfeiffer syndromes-support the hypothesis that TWIST and FGFRs are components of the same molecular pathway involved in the modulation of craniofacial and limb development in humans.

Cytomegalovirus infection enhances the neointima formation in rat aortic allografts: effect of major histocompatibility complex class I and class II antigen differences

BACKGROUND

The development of chronic rejection has emerged as a major cause of long-term graft failure. Previous studies have demonstrated that cytomegalovirus (CMV) infection is associated with an increased incidence of chronic allograft rejection in renal, cardiac, and aortic allografts. This study was designed to investigate the effects of the major histocompatibility complex (MHC) class I or class II mismatches on CMV-enhanced chronic rejection.

METHODS

Aortic transplantation was performed between different inbred rat strain combinations; the Lewis to RP combination was class I-mismatched and Wag/Rij to RP class II-mismatched. At 7, 28, and 90 days after transplantation, the intensity of chronic rejection in mismatched grafts with or without CMV infection was evaluated using histological and immunohistological analysis.

RESULTS

The results of this study demonstrated that CMV infection led to an increased influx of monocytes/ macrophages in class I-mismatched grafts at 1 week after transplantation and enhanced infiltration of T lymphocytes in class II-mismatched grafts at 4 weeks. Although more vascular lesions were observed in the class II-mismatched combinations, an intensified neointima formation by CMV infection was observed only in the MHC class I-mismatched allografts.

CONCLUSIONS

CMV infection may increase neointima formation of allografts when an MHC class I disparity between donor and recipient is present. This may be associated with the increased perivascular influx of monocytes/macrophages observed in CMV-infected animals early after transplantation.

Computer-generated time lines for visualizing and editing epidemiological and biomedical data

Most biomedical data have a temporal dimension. Time-line displays spatialize this dimension and help the viewer comprehend large sets of complex data. If we add ways for users to selectively expand the details of data visible on a time line, even more information can be organized and accessed. Design issues for this kind of display include: how to display time scales that are often wider than the physical display space; how to display events with brief duration; how to display data for two or more events that overlap in time; how to manage the display of data details; how to allow database editing from a time line; and how to facilitate time-based analytical techniques. We describe a time-line display system that addresses each of these issues, and show how it can be used to organize data for an epidemiological study of parental radiation exposure and childhood leukemia. We also suggest further refinements of the time line technique for other biomedical applications.

Tumor necrosis factor-alpha stimulates the maturation of sterol regulatory element binding protein-1 in human hepatocytes through the action of neutral sphingomyelinase

The mechanism by which genes involved in cholesterol biosynthesis and import are preferentially up-regulated in response to sterol depletion was elucidated with the cloning of sterol regulatory element binding protein-1 (SREBP-1). SREBP-1 is a transcription factor whose entry into the nucleus is gated by sterol-regulated proteolysis. We have investigated the role of tumor necrosis factor-alpha (TNF-alpha) as a mediator of SREBP-1 maturation in human hepatocytes. TNF-alpha is capable of inducing SREBP-1 maturation in a time- and dose-dependent manner that is consistent with the kinetics of TNF-alpha-mediated activation of neutral sphingomyelinase (N-SMase). Antibodies to N-SMase inhibit TNF-alpha-induced SREBP-1 maturation suggesting that N-SMase is a necessary component of this signal transduction pathway. Ceramide, a product of sphingomyelin hydrolysis, is also capable of inducing SREBP-1 maturation. The mature form of SREBP-1 generated by TNF-alpha, sphingomyelinase or ceramide treatment translocates to the nucleus and binds the sterol regulatory element. This promotes transcription of the gene upstream of the sterol regulatory element. A unique finding of our studies is that ceramide stimulated SREBP-1 maturation even in the presence of cholesterol and 25-hydroxycholesterol both of which are known suppressors of SREBP-1 maturation. Our findings indicate that ceramide-mediated maturation of SREBP-1 maturation is a novel sterol-independent mechanism by which cholesterol homeostasis may be regulated.

Fibroblast growth factor 2 control of vascular tone

Vascular tone control is essential in blood pressure regulation, shock, ischemia-reperfusion, inflammation, vessel injury/repair, wound healing, temperature regulation, digestion, exercise physiology, and metabolism. Here we show that a well-known growth factor, FGF2, long thought to be involved in many developmental and homeostatic processes, including growth of the tissue layers of vessel walls, functions in vascular tone control. Fgf2 knockout mice are morphologically normal and display decreased vascular smooth muscle contractility, low blood pressure and thrombocytosis. Following intra-arterial mechanical injury, FGF2-deficient vessels undergo a normal hyperplastic response. These results force us to reconsider the function of FGF2 in vascular development and homeostasis in terms of vascular tone control.

Hemodynamic responses to endothelin-1 and endothelin antagonists microinjected into the nucleus tractus solitarius in rats

The role of endothelin-1 (ET-1) within the nucleus tractus solitarius (NTS) in central cardiovascular control was investigated by local microinjections of ET-1 and ET-receptor antagonists. In urethane-anesthetized Sprague-Dawley rats, a unilateral microinjection of ET-1 (1.0, 3.3, and 10.0 pmol) into the NTS significantly increased arterial pressure, left ventricular systolic pressure, and dP/dt(max) in a dose-dependent manner, and slightly decreased heart rate in a dose-independent manner. The pressor effect lasted >90 min. In normotensive rats, neither PD147953, a selective ETA-receptor antagonist, nor PD142893, a mixed ETA- and ETB-receptor antagonist, microinjected into the NTS elicited any changes in arterial pressure or heart rate. The pressor and bradycardic effects evoked by microinjection of ET-1 into the NTS could be blocked by local pretreatment with PD147953 and completely eliminated by intravenous pretreatment with the ganglionic blocker hexamethonium. The arterial baroreflex sensitivity was almost totally suppressed by microinjection of ET-1 (3.3 pmol) in alpha-chloralose-anesthetized Sprague-Dawley rats. A similar pattern of changes in the hemodynamic variables was elicited by microinjection of ET-1 (3.3 pmol) into the NTS in spontaneously hypertensive rats (SHRs) compared with Wistar-Kyoto (WKY) rats. In SHRs, microinjection of PD142893 did not elicit any changes in arterial pressure or heart rate. These results suggest that ET-1 modulates reflex control of hemodynamics by activation of autonomic nerve via ETA receptors in the NTS, and that the responsiveness of SHRs to ET-1 or PD142893 is similar to that of WKY rats.

[New method for preparing oridonin by column chromatography]

Compared with the traditional methods, the separation and preparation of oridonin by column chromatography have the advantages of fast speed, harmlessness and non-pollution of solvent, safety, economy and easily obtained, etc. After re-crystallizing the oridonin content is determined by TLC scanning to be as high as 97.03%.