[Preliminary isolation and identification of neurotrophic factors sensory neurons in spinal dorsal horn of embryonic chicken]

Our previous studies have demonstrated that the extract from dorsal horn of embryonic chicken can promote apparently the neurite growth of spinal ganglion during development. In this study, we investigated progressively the neurotrophic factors for primary sensory neurons in spinal dorsal horn. The tissues of spinal dorsal horn from five hundred Hamburger Stage-40 embryonic chickens were taken. After homogenization and centrifugation, the supernatant was subjected to SDS-polyacrylamide gel electrophoresis (SDS-PAGE) for analyzing the protein in dorsal horn. The simple protein band fishing by cell (SPBFC) technique was employed in finding the protein bands with neurons attached, and then such protein bands, were taken and transferred to nitric cellulose paper for Western hybridization analysis by antibody for NGF, BDNF, NT-3 and GDNF respectively. The results of SPBFC showed that some neurons were attached to gel within the scope of mobility relative front (Rf) 0.10-0.19, 0.30-0.35, 0.50-0.55, 0.60-0.67 and 0.90-0.94 respectively, indicating there were some neurotrophic factors for maintaining neuron survival in the above Rf scope. Moreover, the result of Western hybridization showed that the positive hybridization bands in each scope were that of NGF, BDNF, GDNF; NGF, BDNF, NT-3; NGF, BDNF, NT-3; NGF, NT-3 and BDNF, NT-3 respectively; indicating that the neurotrophic effect of spinal dorsal horn tissue on primary sensory neurons involves NGF, BDNF, NT-3 and GDNF. These also suggest that the neuronal survival effect in each Rf scope involves at least two or more neurotrophic factors.

Synthesis and crystal structure of a novel germanate: (NH4)4[(GeO2)3(GeO1.5F3)2].0.67H2O

The novel microporous germanate (NH4)4[(GeO2)3(GeO1.5F3)2].0.67H2O was prepared from an aqueous solution containing germanium dioxide, pyridine, hydrofluoric acid, and 2,6-diaminopyridine as a template. The solution was kept at 165 degrees C in a Teflon-lined autoclave for 4 days. Large crystals were produced and studied by X-ray powder diffraction, FTIR, thermal analysis, and elemental analysis. The structure was determined by single-crystal X-ray diffraction. The crystal is orthorhombic, space group Pbcn, with a = 7.0065(4) A, b = 11.7976(6) A, c = 19.5200(14) A, and Z = 4. The structure is a layered framework built up from GeO4 tetrahedral and GeO3F3 octahedral units. The polyhedral units are connected in such a way that they form a zeolite-like porous structure with three- and nine-membered rings. Half of the ammonium ions are located inside the nine-membered rings. The other half are above and below the three-membered rings. The connectivity of the germanium polyhedral units is interrupted along the c axis by ammonium ions and water molecules inserted between the layers.

v-Abl utilizes multiple mechanisms to drive G1/S progression in fibroblasts

Transformation of 3T3 fibroblasts by the v-Abl tyrosine kinase replaces mitogenic and adhesion signals normally required for cell cycle progression. A 3T3 cell line conditionally transformed with v-Abl has been used to study v-Abl's effects on cell cycle in the context of either serum depletion or absence of adhesion signals. We show that E2F-dependent mRNAs, encoding proteins required for cell cycle progression, are induced by v-Abl. In addition, we identify two previously unknown targets of v-Abl signaling: (1) cyclin D1 and D2 mRNAs are induced upon v-Abl activation; and (2) the CDK inhibitor p27 is decreased upon v-Abl activation.

Photoinduced dehydrogenation of defects in undoped a-si:H using positron annihilation spectroscopy

We report changes in variable-energy positron annihilation spectroscopy measurements on undoped hydrogenated amorphous silicon films after light soaking. The change, seen predominantly in the high momentum band of the annihilation radiation, is not reversed by thermal annealing. We suggest, following recent models of the Staebler-Wronski effect, that light exposure induces hydrogen trapped in vacancylike defects to become mobile in the Si network. The observations place constraints on models of hydrogen motion fitting macroscopic Staebler-Wronski effect kinetics and may help to achieve a definitive description of metastability in a-Si:H.

p53 deficiency increases transformation by v-Abl and rescues the ability of a C-terminally truncated v-Abl mutant to induce pre-B lymphoma in vivo

Abelson murine leukemia virus (A-MuLV) is an acute transforming retrovirus that preferentially transforms early B-lineage cells both in vivo and in vitro. Its transforming protein, v-Abl, is a tyrosine kinase related to v-Src but containing an extended C-terminal domain. Many mutations affecting the C-terminal portion of the molecule block the pre-B-transforming activity of v-Abl without affecting the fibroblast-transforming ability. In this study we have determined the abilities of both wild-type and C-terminally truncated (p90) forms of v-Abl to transform cells from p53(-/-) mice. Lack of p53 increases the susceptibility of bone marrow cells to transformation by v-Abl by a factor of more than 7 but does not alter v-Abl's preference for B220(+) IgM(-) pre-B cells. p53-deficient mice have earlier tumor onset, more rapid tumor progression, and decreased survival time following A-MuLV infection, but all of the tumors are pre-B lymphomas. Thus, p53-dependent pathways inhibit v-Abl transformation but play no role in conferring preferential transformation of pre-B cells. Surprisingly, the C-terminally truncated form of v-Abl (p90) transforms pre-B cells very efficiently in mice lacking p53, thus demonstrating that the C terminus of v-Abl does not determine preB tropism but is necessary to overcome p53-dependent inhibition of transformation.

Structures of nanometre-size crystals determined from selected-area electron diffraction data

The structure of a new modification of Ti2Se, the beta-phase, and several related inorganic crystal structures containing elements with atomic numbers between 16 and 40 have been solved by quasi-automatic direct methods from single-crystal electron diffraction patterns of nanometre-size crystals, using the kinematical approximation. The crystals were several thousand times smaller than the minimum size required for single-crystal X-ray diffraction. Atomic coordinates were found with an average accuracy of 0.2 A or better. Experimental data were obtained by standardized techniques for recording and quantifying electron diffraction patterns. The SIR97 program for solving crystal structures from three-dimensional X-ray diffraction data by direct methods was modified to work also with two-dimensional electron diffraction data.

Inhibition of v-Abl transformation by p53 and p19ARF

Tumorigenesis is a multistep process that involves the activation of oncogenes and the inactivation of tumor suppressor genes. The transforming activity of the v-Abl oncogene of Abelson murine leukemia virus (A-MuLV) in immortal cell lines has been well studied, while the effects of v-Abl in primary fibroblasts are less clear. Here we show that v-Abl causes cell cycle arrest in primary mouse embryonic fibroblasts (MEFs) and elevated levels of both p53 and the cyclin-dependent kinase inhibitor p21Cip. p53-/- or p19ARF-/- MEFs were resistant to v-Abl-induced cell cycle arrest. Although wild-type MEFs were resistant to v-Abl transforming activity, p53-/- or p19ARF-/- MEFs were susceptible. The results indicate that loss of p19ARF and p53 function plays an important role during the transformation of primary cells by v-Abl. We suggest that although v-Abl is a potent oncogene, its full potential transforming activity cannot be realized until the ARF-, and p53-dependent growth inhibitory pathway is disabled. We also show that p53 is not the mediator of v-Abl toxicity in immortal fibroblasts and does not determine the susceptibility of immortal fibroblasts to v-Abl transformation.

Antibody repertoires of four- and five-feature translocus mice carrying human immunoglobulin heavy chain and kappa and lambda light chain yeast artificial chromosomes

We have produced mice that carry the human Ig heavy (IgH) and both kappa and lambda light chain transloci in a background in which the endogenous IgH and kappa loci have been inactivated. The B lymphocyte population in these translocus mice is restored to about one-third of normal levels, with preferential (3:1) expression of human lambda over human kappa. Human IgM is found in the serum at levels between 50 and 400 microg/ml and is elevated following immunization. This primary human Ab repertoire is sufficient to yield diverse Ag-specific responses as judged by analysis of mAbs. The use of DH and J segments is similar to that seen in human B cells, with an analogous pattern of N nucleotide insertion. Maturation of the response is accompanied by somatic hypermutation, which is particularly effective in the light chain transloci. These mice therefore allow the production of Ag-specific repertoires of both IgM,kappa and IgM,lambda Abs and should prove useful for the production of human mAbs for clinical use.

Induction of inflammatory mediators in human airway epithelial cells by lipid ozonation products

We have proposed that exposure of epithelial cell membrane lipids in the lung (mainly phospholipids) to ozone will generate lipid ozonation products (LOP), which could be responsible for the proinflammatory effects of ozone. The ozonation of phosphocholine, the principal membrane phospholipid, produces a limited number of LOP, including hydroxyhydroperoxides and aldehydes. We now report that exposure of cultured human bronchial epithelial cells to the ozonized 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) product, 1-palmitoyl-2-(9-oxononanoyl)-sn-glycero-3-phosphocholine (PC-ALD), a phospholipase A(2) (PLA(2))-stimulatory LOP, resulted in a 113 +/- 11% increase in the amounts of tritiated platelet-activating factor ((3)H-PAF) released apically. (3)H-PAF release was also induced by 1-hydroxy-1-hydroperoxynonane of ozonized POPC (HHP-C9), a phospholipase C (PLC)- stimulatory LOP (134 +/- 40% increase in (3)H-PAF). PC-ALD at 10 microM, but not HHP-C9, induced a 127 +/- 24% increase in prostaglandin E(2) (PGE(2)) release (n = 6, p < 0.05). In contrast, HHP-C9, but not PC-ALD, induced interleukin (IL)-6 release (178 +/- 23% increase, n = 6, p < 0.05) and IL-8 release (101 +/- 23% increase, n = 8, p < 0. 05). These results suggest that LOP-dependent release of proinflammatory mediators may play an important role in the early inflammatory response seen during exposure to ozone.

[Magnetic resonance imaging in 40 cases of optic neuritis]

OBJECTIVE

To explore the clinical value of magnetic resonance imaging (MRI) in optic neuritis.

METHODS

Forty patients with optic neuritis were examined with the spectral presaturation inversion recovery and fluid attenuated inversion recovery.

RESULTS

The lesion was frequently seen in orbital portion (86.7%) and intracanalicular portion (29.3%), and primarily in the axial part (49.3%) and transverse section (38.7%) of the optic nerve. The longitudinal extent of lesion was from 2 to 35 mm (mean, 12.6 mm), the visual acuity of patients with optic neuritis was related to the site of the lesion, and negatively correlated with the longitudinal extent of lesion of logarithm curve. A poor visual acuity (< 0.01) was significantly associated with lesion of greater extent > 10 mm and the transverse or axial lesion, but the good visual acuity (>or= 0.3), with the lesion of smaller extent < 10 mm and the axial or peripheral lesion. In addition, paramagnetic contrast-medium, Gd-DTPA, enhancement scanning was carried out in 11 cases of optic neuritis, of them the visual acuity was increased in 10 cases after administration of corticosteroid, and in one case, visual improvement was not seen.

CONCLUSION

MRI is a new and useful equipment which is helpful in the diagnosis and treatment of optic neuritis.

B-cell tumorigenesis in mice carrying a yeast artificial chromosome-based immunoglobulin heavy/c-myc translocus is independent of the heavy chain intron enhancer (Emu)

We have used YAC (yeast artificial chromosome) technology to create large translocation regions where the c-myc proto-oncogene is coupled to the core region of the human immunoglobulin heavy chain (IgH) locus (from VH2-5 through to Cdelta). Chimeric mice were obtained from embryonic stem cells carrying a single copy of the 240-kb IgH/c-myc translocation region. B-cell tumorigenesis occurs in the translocus mice, even when the entire Emu intron enhancer region between the joining segments and switch mu is deleted. This demonstrates that as yet unidentified regulatory elements in the IgH locus, independent from the known enhancers, are sufficient to cause B-cell specific activation of c-myc after translocation. The phenotype of tumors from IgH/c-myc YAC transgenic mice with or without Emu (B220+, IgM+/IgD+) is reminiscent of Burkitt's lymphoma. A rapidly expanding abnormal B-cell population is present at birth and accumulates in bone marrow, periphery, and spleen, well before discrete tumor establishment. Molecular analysis identified a clonal origin, with rearrangement of one mouse heavy chain allele retained in tumor cells from different sites, whereas subsequent rearrangements of heavy or light chain loci can be diverse. These mice routinely develop mature B-cell tumors early in life and may provide an invaluable resource of a B-cell lymphoma model.

Thermolysis of coenzymes B12 at physiological temperatures: activation parameters for cobalt-carbon bond homolysis and a quantitative analysis of the perturbation of the homolysis equilibrium by the ribonucleoside triphosphate reductase from Lactobacillus leichmannii

The kinetics of the thermolysis of 5'-deoxyadenosylcobalamin (AdoCbl, coenzyme B12) in aqueous solution, pH 7.5, have been studied in the temperature range 30-85 degrees C using AdoCbl tritiated at the adenine C2 position and the method of initial rates. Combined with a careful analysis of the distribution of adenine-containing products, the results permit the dissection of the competing rate constants for carbon-cobalt bond homolysis and heterolysis. After correction for the temperature-dependent occurrence of the much less reactive base-off species of AdoCbl, the activation parameters for homolysis of the base-on species were found to be delta H++homo,on = 33.8 +/- 0.2 kcal mol-1 and delta S++homo,on = 13.5 +/- 0.7 cal mol-1 K-1, values not significantly different from those determined by Hay and Finke (J. Am. Chem. Soc. 108 (1986) 4820), in the temperature range 85-115 degrees C. In contrast, the heterolysis of base-on AdoCbl was characterized by a much smaller enthalpy of activation (delta H++het,on = 18.5 +/- 0.2 kcal mol-1) and a negative entropy of activation (delta S++het,on = -34.0 +/- 0.7 cal mol-1 K-1) so that heterolysis, which is minor pathway at elevated temperatures, is the dominant pathway for AdoCbl decomposition at physiological temperatures. Using literature values for the rate constant for the reverse reaction, the equilibrium constant for AdoCbl homolysis at 37 degrees C was calculated to be 7.9 x 10(-18). Comparison with the equilibrium constant for this homolysis at the active site of the ribonucleoside triphosphate reductase from Lactobacillus leichmannii shows that the enzymes shifts the equilibrium constant towards homolysis products by a factor of 2.9 x 10(12) (17.7 kcal mol-1) by binding the thermolysis products with an equilibrium constant of 7.1 x 10(16) M-2, compared to the bonding constant for AdoCbl of 2.4 x 10(4) M-1.

Interaction of maturation delay and nonlinear birth in population and epidemic models

A population with birth rate function B(N) N and linear death rate for the adult stage is assumed to have a maturation delay T>0. Thus the growth equation N'(t)=B(N(t-T)) N(t-T) e(-)d(1)T- dN(t) governs the adult population, with the death rate in previous life stages d(1)>==0. Standard assumptions are made on B(N) so that a unique equilibrium N(e) exists. When B(N) N is not monotone, the delay T can qualitatively change the dynamics. For some fixed values of the parameters with d(1)>0, as T increases the equilibrium N(e) can switch from being stable to unstable (with numerically observed periodic solutions) and then back to stable. When disease that does not cause death is introduced into the population, a threshold parameter R(0) is identified. When R(0)<1, the disease dies out; when R(0)>1, the disease remains endemic, either tending to an equilibrium value or oscillating about this value. Numerical simulations indicate that oscillations can also be induced by disease related death in a model with maturation delay.

Detection of gastric slow wave propagation from the cutaneous electrogastrogram

The gastric slow wave is originated in the proximal stomach and propagates distally toward the pylorus. It determines the maximum frequency and propagation of gastric contractions. The aim of this study was to detect the propagation of the gastric slow wave from the surface electrogastrogram (EGG). The study was performed in 11 healthy subjects of normal weight. Gastric myoelectrical activity was recorded for 1 h in the fasting state with the use of a specially designed multichannel recording device that was composed of four identical amplifiers with cutoff frequencies of 1.8 and 16.0 cycles/min. Four active electrodes were placed on the abdomen along the gastric axis and were connected to a common reference electrode placed near the xiphoid process, yielding four-channel bipolar EGG signals. Cross-covariance analysis was performed to compute the time lag among the four channels. There was a time lag in EGG waveform between channels 1 and 4 (9.6 +/- 1.1 s); the average time during which the time lag was observed (>/=3 s) was 89.9 +/- 9.0%. There was a significant difference in the time lag among different adjacent channels (P < 0.04); the time lag observed between channels 3 and 4 was significantly smaller than that between channels 1 and 2 (P < 0.03). No correlation was found between the body mass index and the time lag between channels 1 and 4 (r = -0.31, P = 0.3). It was concluded that, with a multichannel recording device with identical multiamplifiers and an appropriate arrangement of abdominal electrodes, the propagation of the gastric slow wave could be identified from the EGG in healthy subjects. This method may be used to detect the coupling of the gastric slow wave noninvasively.

On the phase problem in electron microscopy: the relationship between structure factors, exit waves, and HREM images

In electron microscopy, the word phase is used for different physical phenomena, including crystallographic structure-factor phases and the electron wave phases. This has resulted in great confusion, as to whether the phase information is present or lost when an image is recorded. The aim of this paper is to solve this phase confusion problem by studying the relationships between structure factors, exit waves, and high-resolution electron microscopy (HREM) images. Three approaches are taken. First phases at different stages of the imaging processes are compared analytically for a crystal that can be considered a weak phase object (WPO). Then these different phases are calculated by the multi-slice method based on dynamical diffraction theory, and their numerical values are compared. Finally, the validity of the theoretical description is checked by comparison with experimental data on a real crystal, Ti(2)S. It is demonstrated that it is possible to obtain accurate structure factor-phases directly from HREM images by crystallographic image processing. The two major methods for structure determination from HREM images-exit wave reconstruction and crystallographic image processing-are compared. It is shown that the information utilised by the two methods as well as the results are essentially the same.

Measurement of crystal thickness and crystal tilt from HRTEM images and a way to correct for their effects

The effects of thickness and tilt angle are studied numerically on experimental high-resolution transmission electron microscope (HRTEM) images of a wedge-shaped metal oxide crystal. For sufficiently thin and well-aligned crystals, the amplitudes and phases of the Fourier transforms of the HRTEM images are essentially the same as the crystallographic structure factors. For tilted crystals, the changes of amplitudes and phases as a function of increased thickness and tilt angle can be described by a simple model. A method is presented by which the local thickness can be determined from one HRTEM image and one convergent-beam electron diffraction pattern from the same crystal. It is also shown how the projected potential can be reconstructed from HRTEM images of tilted crystals, disclosing the crystal structure, even from quite thick (>20 nm) samples.

Stable isotopic studies of earthworm feeding ecology in tropical ecosystems of Puerto Rico

Feeding strategies of earthworms and their influence on soil processes are often inferred from morphological, behavioral and physiological traits. We used (13)C and (15)N natural abundance in earthworms, soils and plants to explore patterns of resource utilization by different species of earthworms in three tropical ecosystems in Puerto Rico. In a high altitude dwarf forest, native earthworms Trigaster longissimus and Estherella sp. showed less (15)N enrichment ((15)N = 3-6 per thousand) than exotic Pontoscolex corethrurus ((15)N =7-9 per thousand) indicating different food sources or stronger isotopic discrimination by the latter. Conversely, in a lower altitude tabonuco forest, Estherella sp. and P. corethrurus overlapped completely in (15)N enrichment ((15)N = 6-9 per thousand), suggesting the potential for interspecific competition for N resources. A tabonuco forest converted to pasture contained only P. corethrurus which were less enriched in (15)N than those in the forest sites, but more highly enriched in (13)C suggesting assimilation of C from the predominant C(4) grass. These results support the utility of stable isotopes to delineate resource partitioning and potential competitive interactions among earthworm species. Copyright 1999 John Wiley & Sons, Ltd.

Monitoring catalytic reaction of bilirubin oxidase and determination of bilirubin and bilirubin oxidase activity by capillary electrophoresis

Micellar electrokinetic chromatography (MEKC) has been exploited as an analytical method for the separation as well as for the determination of serum bilirubin fractions (alpha-, beta-, gamma- and delta-fraction), the activity of bilirubin oxidase (BOD), and for monitoring the catalytic reaction of BOD. The samples were followed by detection at 450 nm. The average limit of detection was in the 5.0 microM concentration range. The relative standard deviation (RSD) of migration times and peak area of bilirubin was less than 0.25% and 3.0%, respectively. This allowed us complete separation of the four bilirubin fractions (alpha-, beta-, gamma- and delta-fraction) and monitoring of the oxidation progress and the assay of the activity of bilirubin oxidase. The MEKC method is a convenient technique for studying the catalytic reaction of bilirubin oxidase at different pH and assaying the relationship between the four bilirubin fractions and diseases.

[Distribution of nitric oxide synthase-positive neurons in the hypothalamus of cat]

NADPH-diaphorase histochemistry was used to study the distribution of Nitric Oxide Synthase (NOS)-Positive neurons in the hypothalamus of adult cat. NOS-positive neurons were observed in the paraventricular hypothalamic nucleus, suprachiasmatic nucleus, dorsomedial hypothalamic nucleus, perifornical nucleus, anterior hypothalamic area and lateral hypothalamic area. Two differences between the cat and rat were noticed. Firstly, NOS-positive neurons were observed in the suprachiasmatic nucleus of cat, but the neurons in that of rat were negative for NOS. Secondly, the neurons in supraoptic nucleus of rat exhibited an intensive reaction to NADPH-diaphorase, but those in that of cat were faintly visible.

A human immunoglobulin lambda locus is similarly well expressed in mice and humans

Transgenic mice carrying a 380-kb region of the human immunoglobulin (Ig) lambda light (L) chain locus in germline configuration were created. The introduced translocus on a yeast artificial chromosome (YAC) accommodates the most proximal Iglambda variable region (V) gene cluster, including 15 Vlambda genes that contribute to >60% of lambda L chains in humans, all Jlambda-Clambda segments, and the 3' enhancer. HuIglambdaYAC mice were bred with animals in which mouse Igkappa production was silenced by gene targeting. In the kappa-/- background, human Iglambda was expressed by approximately 84% of splenic B cells. A striking result was that human Iglambda was also produced at high levels in mice with normal kappa locus. Analysis of bone marrow cells showed that human Iglambda and mouse Igkappa were expressed at similar levels throughout B cell development, suggesting that the Iglambda translocus and the endogenous kappa locus rearrange independently and with equal efficiency at the same developmental stage. This is further supported by the finding that in hybridomas expressing human Iglambda the endogenous L chain loci were in germline configuration. The presence of somatic hypermutation in the human Vlambda genes indicated that the Iglambda-expressing cells function normally. The finding that human lambda genes can be utilized with similar efficiency in mice and humans implies that L chain expression is critically dependent on the configuration of the locus.

Postprandial changes of sympathovagal balance measured by heart rate variability

The aim of this study was to investigate the sympathovagal balance after meals by measuring the spectral analysis of heart rate variability (HRV). Nine healthy volunteers were enrolled in this study. The electrocardiogram (ECG) was recorded for 30 min in a fasting state and 60 min after a 500-kcal test meal. The HRV was derived from the ECG and was measured by power spectral analysis using fast-Fourier transform algorithm. It reveals two dominant spectral components. The low-frequency (LF) band reflects primarily sympathetic activity with some parasympathetic input. The high-frequency (HF) band is a reflection of parasympathetic (vagal) activity. The LF-to-HF ratio is considered a marker of sympathovagal balance. It was found that the postprandial LF-to-HF ratio, compared with the fasting state, was significantly increased at both the first 30 min (2.50 +/- 0.49 vs 1.78 +/- 0.33, P < 0.05) and the second 30 min (2.68 +/- 0.55 vs 1.78 +/- 0.33, P < 0.05). The postprandial HF diminished significantly at both the first (16.0 +/- 0.5 vs 21.8 +/- 4.2, P < 0.05) and the second (13.8 +/- 9.5 vs 21.8 +/- 4.2, P < 0.05) 30-min period. In conclusion, the postprandial sympathovagal ratio shows a sustained elevation lasting 1 hr, mainly attributed to diminished vagal activity.

Protein changes associated with ionizing radiation-induced apoptosis in human prostate epithelial tumor cells

Ionizing radiation (IR) is an important component in the therapy of localized prostate cancer. Identification of protein alterations during IR-induced apoptosis prostate cancer cells is an important step toward understanding the new metabolic status of the dying cell. In the present study, we report changes in protein profile that define the execution phase of the apoptotic response in the in vitro model of tumorigenic radiation-transformed SV40-immortalized human prostate epithelial cells (267B1-XR), induced to undergo programmed cell death by IR. We employed an approach that involves use of analytical two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) coupled with Western blotting with specific antisera. Our results point out that apoptotic cells experience significant reduction in the levels of the intermediate filament proteins, keratins-18, 19, vimentin and the associated 14-3-3 adapter proteins. At the same time, molecular chaperones such as glucose-regulated protein 94, calreticulin, calnexin, and protein disulfide isomerase exhibit marked accumulation in these dying cells. The present data indicate that apoptosis-associated processes in prostate epithelial cells include solubilization of the rigid intermediate filament network by specific proteolysis as well as increased levels of endoplasmic reticulum (ER) proteins with chaperone functions.

[Investigation of factors affecting the development of COPD]

OBJECTIVE

To investigate the factors which affect the development of COPD.

METHODS

88 patients with mPAP less than 20 mm Hg were followed up by 5 - 20 years. Pulmonary ventilation, blood gas analysis, ECG, pulmonary hemodynamic parameters and oxygen saturation at night were performed one time every 5 years.

RESULTS

The results showed that: 5 year, 10 year and 20 year's mortality is 6%, 25% and 43% respectively; MVV%, FEV(1)% and PaO(2) declined accompanied by the increase of PaCO(2); among 41 patients with mPAP 16 - 20 mm Hg, 20 patients' mPAP were more than 20 mm Hg and 15 patients died after 10 years' follow up. Among 16 patients with the declination of oxygen saturation, 8 patients' mPAP were more than 20 mm Hg and 6 patients died. 57 strains of infectious bacteria were found in 88 patients' sputum with 43 strains in the death group.

CONCLUSIONS

These results demonstrated that COPD is a kind of chronic diseases with high death rate; infection, decline of oxygen saturation at night and mPAP more than 16 mm Hg were high risk factors in COPD.

Gastric myoelectrical activity in patients with cervical spinal cord injury

OBJECTIVE

Dyspeptic symptoms are common in patients with cervical spinal cord injury (SCI). The supraspinal control of sympathetic innervation to the stomach is interrupted in these patients. Gastric emptying has been reported to be delayed in some patients with cervical SCI. Gastric myoelectrical activity is known to regulate gastric motility and is correlated with gastric emptying. The change in gastric myoelectrical activity after cervical SCI is unknown; our aim was to investigate it.

METHODS

The study was performed in 12 cervical SCI patients and 14 healthy controls. Gastric myoelectrical activity was recorded using surface electrogastrography for 30 min in the fasting state and 1 h after a standard test meal. Spectral analysis was performed to compute the following parameters from the electrogastrogram; investigated were the percentage of 2-4 cycles/min (cpm) slow waves, the instability coefficient (IC) of the dominant frequency, the postprandial increment of dominant frequency (deltaF), and its power (deltaP).

RESULTS

In both fasting and fed states, regular and stable gastric slow waves were observed in both the control group and patients with cervical SCI. The percentage of normal 2-4 cpm slow waves (preprandial, 80.7+/-3.6% vs 91.5+/-3.7%, p > 0.05; postprandial, 82.0+/-4.4% vs 87.2+/-4.2%, p > 0.05) and IC (preprandial, 0.19+/-0.04% vs 0.28+/-0.05%; postprandial, 0.24+/-0.04% vs 0.27+/-0.02%, p > 0.05) were not significantly different between the two groups. The dominant frequency and its power were also similar between the two groups, no matter whether in the fast (frequency, 2.92+/-0.3 vs 2.93+/-0.06 cpm; power, 30.05+/-1.29 vs 29.08+/-1.23 dB, p > 0.05) or fed (frequency, 3.17+/-0.07 vs 3.02+/-0.06 cpm; power, 32.55+/-0.90 vs 32.07+/-1.18 dB,p > 0.05) state. The postprandial response measured by deltaF (0.25+/-0.09 vs 0.09+/-0.07 cpm, p > 0.05) and deltaP (2.52+/-1.10 vs 2.24+/-1.20 dB, p > 0.05) were also similar between the two groups.

CONCLUSION

Gastric myoelectrical activity was not altered after cervical SCI.

[Change of hymodynamics and circulating endothelial cells in chronic obstructive pulmonary diseases (COPD) and cor pulmonale patients]

OBJECTIVE

To investigate the vascular endothelial injuries by observing the changes of circulating endothelial cells (CEC) numbers in blood and hemodynamics in COPD and cor pulmonale patients.

METHOD

The arterial catheterion technique and CEC collection technique were used, superoxide dismutase (SOD) and malondialdyhyde(MDA) levels were determined respectively.

RESULT

mPAP (3.76 +/- 0.75 kPa) and CEC (16.70 +/- 2.65/0.9 microliter), MDA (6.98 +/- 1.47 mumol/L) in the chronic cor pulmonale are higher than that of mPAP (2.09 +/- 0.41 kPa) and CEC (8.48 +/- 2.23 microliters) in COPD, the numbers of CEC are adversely correlated to PaO2 (gamma = 0.9423, P < 0.001) and positively correlated with mPAP (gamma = 0.8270, P < 0.001), superoxide dismutase(SOD) was decreased.

CONCLUSION

mPAP, CEC are higher in cor pulmonale than that in COPD, CEC numbers rise when the PaO2 was lowered, hypoxia may worsen the vascular endothelial injuries.

[Ineffective platelet transfusion in patients with hematology malignancy]

OBJECTIVE

To explore the relationship between the effects of platelet transfusion and histocompatibility antigen (HLA).

METHODS

The relationship between the corrected count increment (CCI) of platelet with lymphocytotoxicity test (LCT) and human histocompatibity antigen system-I subtype (HLA-I) in 126 hospitalized patients who accepted platelet transfusion.

RESULTS

Ineffective platelet transfusion was strongly related to LCT positive and LCT intensity (P < 0.01). The HLA A2 gene frequency was 0.91. The frequency was much higher than that of health human being (0.54).

CONCLUSION

Positive LCT was mainly immune factor for ineffective platelet transfusion. CCI and LCT should be the routine test for platelet patients. It may improve the effects of platelet transfusion.

Biological behavior of plasmid in Rhizobium sp. strain S25 from Tephrosia candida

Rhizobium sp. strain S25 was isolated from the nodule on Tephrosia candida in Hainan Province, China. The strain showed high stress tolerance. The plasmid profile of strain S25, examined by the Eckhardt procedure, indicated that the strain harbors only one plasmid with an estimated size of 150 kb. The plasmid was shown to carry nod and nif genes by hybridization with probes of nodABC and nifHDK genes. Plasmid curing was carried out using the Bacillus subtilis sacB to generate derivatives of strain S25. In comparison with the parent strain S25, the cured derivative lost its ability to nodulate the host plant. Loss of the plasmid reduced significantly the strain's tolerance to acid, nitrous, and multiple antibiotics. The properties of the cured strain also indicated that the plasmid was involved in carbon and nitrogen metabolism. Reintroduction of the plasmid from S25 in the cured derivative restored its original biological phenotypes.

[Quantitative analysis of motor unit potential in patients with dermatomyositic disease]

To diagnose dermatomyositic disease well, we adopted the method of EMG in an investigation of 37 patients. Their electrophysiologic parameters of 220 muscles were determined. The results showed that the parameters, including the average DUR, AMP, RISE, AREA, AR/AM and SI of motor unit potentials (MUPs) were significantly lower than those of the controls (P < 0.05 or P < 0.01), especially AREA and SI (P < 0.01). But no remarkable difference was found between the muscles on the two sides of the diseased extremties. These findings suggest that quantitative analysis of MUPs is of importance to diagnosis of dermatomyositic disease and the parameters such as AREA and SI may provide more valuable information.

[Separation of celiprolol enantiomer by high performance liquid chromatography with urea derivative as chiral stationary phase]

Celiprolol enantiomer was resolved directly by using normal-phase HPLC with urea derivative as chiral stationary phase (CSP). The resolution condition was optimized by varying the content of ethanol and 1, 2-dichloroethane in the mobile phase. The effects of the two components on stereoselectivity factor (alpha) and stereochemical resolution factor (Rs) are demonstrated. The higher the 1,2-dichloroethane content the faster the elution of solute is, but the lower the values of alpha and Rs are. For a suitable content of ethanol in mobile phase, the maximum resolution factor (Rs) can be obtained. Ethanol is a strong proton-donor and proton-acceptor. Its strong hydrogen bond interaction with solute and CSP is important for the direct resolution. In order to obtain both the low retention time and a high Rs, we chose the mobile phase with n-hexane:1,2-dichloroethane:ethanol (V/V/V) = 77:21:2. Other organic modifiers such as methanol, iso-propanol, n-butanol and acetonitrile were also used. Iso-propanol, methanol and n-butanol showed longer retention time and lower values of alpha and Rs than ethanol. Acetonitrile is only a proton-acceptor and has weak hydrogen bond interaction with solute and CSP, so resolution wasn't obtained. The elution order of enantiomer was also discussed. We thought that the hydrogen bond interaction between solute and the (S)-val component of CSP may mainly control the chiral recognition. The interaction strength is different between (R)- and (S)-celiprolol, so the celiprolol enantiomer was resolved. And the elution order is S, R.

Structural and enzymatic studies of a new analogue of coenzyme B12 with an alpha-adenosyl upper axial ligand

A new analogue of coenzyme B12 (5'-deoxyadenosylcobalamin, AdoCbl), in which the configuration of the N-glycosidic bond in the Ado ligand is inverted [(alpha-ribo)AdoCbl], has been synthesized and its crystal structure determined by X-ray diffraction [MoKalpha, lambda = 0.71073 A, monoclinic P212121, a = 16.132(12) A, b = 21. 684(15) A, c = 27.30(3) A, 9611 independent reflections, R1 = 0. 0708]. As suggested by molecular mechanics modeling before the structure was known, the Ado ligand lies over the southern quadrant of the molecule, as is the case for AdoCbl. The most striking feature of the structure is disorder in the orientation of the adenine (Ade) moiety relative to the ribose of the Ado ligand. This was resolved with a two-state model in which in the major (0.57 occupancy) conformer the A16(O)-A11-A9(N)-A8 dihedral angle is 1.9 degrees and the Ade is virtually perpendicular to the corrin ring; in the minor conformer, the Ade is tilted down, and this dihedral is -48.7 degrees. The Co-C and axial Co-N bond lengths and the Co-C-C bond angle are quite similar to those in AdoCbl. The corrin ring is considerably flatter than that of AdoCbl, with a fold angle of 11.7 degrees. The molecule was successfully modeled by molecular mechanics (MM), and rotation of the Ado ligand relative to the corrin gave rise to four locally minimum structures with the Ado in the southern, eastern, northern, or western quadrant, with the southern conformation as the global minimum, as is the case with AdoCbl itself. Nuclear Overhauser effects (nOe's) observed by two-dimensional (2D) NMR were incorporated as restraints in molecular dynamics (MD) and simulated annealing (SA) calculations. A MD simulation at 300 K showed that only the southern conformation is populated with the Ado ligand confined to an arc from over C15 to over C12, while the Ade ring oscillates from perpendicular to parallel to the corrin ring. Twenty-seven structures were collected by MD-SA. Most of these annealed into the southern conformation, but examples of the other conformations were also found. The new analogue is a partially active coenzyme for the ribonucleotide reductase from Lactobacillus leichmanii with maximal activity that is 9.7% of that of AdoCbl itself, and a very high Km value (245 microM compared to 0.54 microM for AdoCbl). In addition, the rate constant for enzyme-induced carbon-cobalt bond cleavage of (alpha-ribo)AdoCbl is 160-fold smaller than that for AdoCbl, and only 1/3 as much cob(II)alamin is produced at the active site.

Lipid ozonation products activate phospholipases A2, C, and D

Ozone exposure, in vitro, has been shown to activate phospholipases A2 (PLA2), C (PLC), and D (PLD) in airway epithelial cells. However, because of its high reactivity, ozone cannot penetrate far into the air/lung tissue interface. It has been proposed that ozone reacts with unsaturated fatty acids (UFA) in the epithelial lining fluid (ELF) and cell membranes to generate a cascade of lipid ozonation products (LOP) that mediate ozone-induced toxicity. To test this hypothesis, we exposed cultured human bronchial epithelial cells (BEAS-2B) to LOP (1-100 microM) produced from the ozonation of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC) and measured the activity of PLA2, PLC, and PLD. The PLA2 isoform responsible for arachidonic acid release (AA) in stimulated cultures was also characterized. Activation of PLA2, PLC, and PLD by three oxidants, hydrogen peroxide (H2O2), tert-butyl hydroperoxide (t-BOOH) and 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH) also was measured and compared to that of LOP. The derivatives of ozonized POPC at the sn-2 residue, 9-oxononanoyl (PC-ALD), 9-hydroxy-9-hydroperoxynonanoyl (PC-HHP), and 8-(-5-octyl-1,2,4-trioxolan-3-yl-) octanoyl (POPC-OZ) selectively activated PLA2 in a dose-dependent fashion. Cytosolic PLA2 (cPLA2) measured in the cytosolic fraction of stimulated cell lysates was found to be the predominant isoform responsible for AA release. PLC activation was exclusively induced by the hydroxyhydroperoxide derivatives. PC-HHP and the 9-carbon hydroxyhydroperoxide (HHP-C9) increased PLC activity. PLD activity also was induced by LOP generated from POPC. Incubation of cultures with H2O2 alone did not stimulate PLC; however, in the presence of the aldehyde, nonanal, a 62 +/- 2% increase in PLC activity was found, suggesting that the increase in activity was due to the formation of the intermediate HHP-C9. t-BOOH, and AAPH also failed to induce PLA2 activation, but did activate PLC, under conditions of exposure identical to that of LOP. Only t-BOOH activated PLD. These results suggest that biologically relevant concentrations of LOP activate PLA2, PLC, and PLD in the airway epithelial cell, a primary target to ozone exposure. The activation of these phospholipases may play a role in the development of lung inflammation during ozone exposure.

Determination of polyamines in human prostate by high-performance liquid chromatography with fluorescence detection

A high-performance liquid chromatographic method for the determination of polyamines in human prostate has been developed. This method is based on pre-column derivatization with dansyl chloride (Dns-Cl). The derivatives were separated on a muBondapak C18 column (250x4.6 mm I.D.; 10 microm), and eluted with methanol and distilled water using a one-step linear gradient. The column eluate was monitored by fluorescence detection (excitation, 370 nm; emission, 506 nm). The within-assay precision of the study (C.V.) was as follows: putrescine (PUT) 2.88%, spermidine (SPD) 2.94% and spermine (SP) 1.17%. The between-assay precision (C.V.) was: PUT 2.66%, SPD 3.06%, SP 2.79%. The recovery was greater than 97%. The detection limit for PUT, SPD and SP were 0.05, 0.08 and 0.06 nmol/ml, respectively. In contrast to other studies, sample or polyamine derivatives did not require extraction with an organic solvent such as ethanol, evaporation under vacuum or other condensation procedures. This is a simple, rapid and sensitive method that can be applied to the determination of polyamines in nearly all biological tissues and body fluids, such as urine and serum.

[Antiepileptic effects of nimodipine on penicillin-induced seizures in rats]

Injecting penicillin (PNC) intraperitoneally in Wistar rats, we observed their epileptic behaviour and electroencephalographys. The results showed that nimodipine (NIM), a calcium antagonist, could inhibit the seizures and epileptic discharges significantly. No epileptic action was noted while NIM was injected before PNC. It supports our consideration of NIM as a new sort of nonsedative anticonvulsant in clinical practice.

[Investigation of potency to produce interleukin-2 of the peripheral blood T lymphocytes in patients with hemorrhagic stroke]

For further understanding the changes in immune function of the patients with hemorrhagic stroke, we investigated the activity of interleukin-2 (IL-2) in the peripheral blood T lymphocytes from 32 patients. The results showed that the levels of IL-2 in the patients were lower than those of the healthy controls, but no significant difference was observed between the cerebral hemorrhage group and subarachnoid hemorrhage group. It suggests the cellular immune function of patients at the acute period is low. We consider that IL-2 might be of use as a kind of therapeutic measure to modulate patients' immune function and treat the diseases.

[Role of pulmonary arterial angiotensin converting enzyme in development of hypoxic pulmonary hypertension]

OBJECTIVE

To study the effect of local pulmonary arterial renin-angiotensin system on hypoxic pulmonary hypertension(PAH).

METHOD

Normobaric hypoxic PAH animal model was adopted. Systolic pulmonary arterial pressure(PAPs), pulmonary arterial angiotensin converting enzyme(ACE) activity, collagen content(HP) were measured and ultrastructure of pulmonary smooth muscle cells (SMC) and was observed.

RESULTS

During hypoxia, PAPs, pulmonary ACE activity, HP increased significantly and SMC changed into secretive phenotype. Treatment with cilazapril, an ACE inhibitor, decreased ACE activity along with reversal of PAPs. HP and SMC phenotype.

CONCLUSIONS

Pulmonary ACE participated in the modulation of changes of SMC phenotype and collagen metabolism during hypoxic PAH.

Structural Model of the Orthorhombic Non-Fibonacci Approximant in the Al12Fe2Cr Alloy

Al5.103(Fe, Cr), orthorhombic, Imm2, a = 12.34, b = 12.41, c = 30.71 Å, V = 4701 Å3, atoms/cell = 305 (average), D x \simeq 3.4 g cm−3. A structural model of the non-Fibonacci approximant O-AIFeCr with composition Al5.103(Fe, Cr) found in an Al12Fe2Cr alloy has been derived from its high-resolution electron microscopy images and the structure of the hexagonal \mu-Al4Mn [Shoemaker, Keszler & Shoemaker (1989). Acta Cryst. B45, 13–20], being isostructural to \mu-Al4Cr. Among the 14 unique positions of transition metal (TM) atoms, 13 are icosahedrally coordinated: five of these icosahedra interpenetrate into each other, forming icosahedral chains along [010], and the remaining eight icosahedra with their twofold axis parallel to this axis. This structural model describes a (010) layer structure with a sequence P^{m}FP(P^{m}FP)_I, where a flat layer F (a mirror plane) is sandwiched between two puckered P and P m layers, and (P^{m}FP)I is related to P^{m}FP through a body-centred translation. The interatomic distances are 2.51–2.74 Å for TM—TM, 2.38–2.99 for TM—Al and 2.41–3.18 Å, for Al—Al. Simulated images and electron diffraction patterns calculated based on this structural model are comparable with the experimentally observed results.

[Alterations of substance P-immune reaction positive neurons of cerebral tissues in epileptic rats]

Employing the immunocytochemical analysis, we observed the alterations of Substance P-Immune Reaction (SP-IR) positive neurons of the cerebral cortex, hippocampus and amygdala in rats suffering from epilepsy induced by Penicillin (PEN). The result showed that the number of neurons of epileptic group was higher than that of the control group and no significant change in the rumber of neurons was observed in the group in which PEN was given after injection of Nimodine. It indicates that SP and Ca2+ participate in the process of epileptogenesis.

Rapid induction of B-cell lymphomas in mice carrying a human IgH/c-mycYAC

Activation of the c-myc proto-oncogene by one of the immunoglobulin (Ig) loci after chromosomal translocation is a consistent feature of Burkitt's lymphoma. Different subtypes of this tumor vary in the molecular architecture of the translocation region. In most cases there are no known regulatory elements of the Ig locus neighboring the oncogene and this considerably obscures the mechanism of its deregulation. In order to assess possible oncogene activation signals, we produced an experimental translocation region by insertion of a c-myc gene about 50 kb from the IgH intron enhancer in a yeast artificial chromosome (YAC) containing a 220 kb region of the human Ig heavy chain (IgH) locus. Single copy integration of this YAC into the genome of mouse embryonic stem (ES) cells was achieved by spheroplast fusion. Chimeric mice derived from these ES cells developed monoclonal B-cell lymphomas expressing surface IgM by 8-16 weeks of age. The IgH/c-myc translocus showed different V(h)DJ(H) rearrangement in almost all tumors without any alterations of the distance between c-myc and the IgH intron enhancer. This mouse model can be used for the in vivo analysis of c-myc deregulation and the tumor formation capacity of the IgH locus in aberrant rearrangements.

Induction of c-myc transcription by the v-Abl tyrosine kinase requires Ras, Raf1, and cyclin-dependent kinases

v-Abl is an oncogenic form of the c-Abl nonreceptor tyrosine kinase. v-Abl induces transcription of c-myc, and c-Myc function is a necessary but not sufficient component of the v-Abl transformation program. Previously we showed that the E2F site in the c-myc promoter is a v-Abl response element and that v-Abl appears to induce c-myc by initiating a phosphorylation cascade that ultimately activates E2F-binding proteins. In this work we have investigated the signaling pathway between the v-Abl tyrosine kinase and activated E2F proteins. We show that the Ras GTPase and Raf1 serine/threonine kinase are required in this pathway. However, in contrast to other aspects of v-Abl signaling, induction of c-myc transcription is independent of the Rac GTPase. Our results also establish a requirement for activated cyclin-dependent kinases (cdks), as v-Abl-dependent induction of c-myc transcription is blocked by cdk inhibitor p21 and induction of c-myc is accompanied by activation of cdk2 and cdk4. Finally, we show that v-Abl-dependent induction of c-myc is accompanied by hyperphosphorylation of pRb, p107, and p130. On the basis of these data, we propose a model for the signaling path from v-Abl to c-myc.

Anti-tumor promoting activity of canventol and its synthetic analogs through inhibition of protein isoprenylation

Canventol, a synthetic compound, is a new inhibitor of tumor promotion on mouse skin by okadaic acid. We previously reported that canventol acts by inhibiting both protein isoprenylation and tumor necrosis factor-alpha (TNF-alpha) release. In this study we examined the potencies of 10 newly synthesized canventol analogs through their effect on mevalonate metabolism, and then examined 3 representative analogs for inhibition of protein isoprenylation. Since canventol in vitro did not directly inhibit farnesyl protein transferase or geranylgeranyl protein transferase-I, the effects of canventol and its synthetic analogs on the fate of [3H]mevalonate in cells were studied. Canventol at 500 microM changed the ratio of newly synthesized sterols (cholesterol and lathosterol) to ubiquinones from 0.7 to 8.2 in NIH/3T3 cells which had previously been labeled with [3H]mevalonate, suggesting that the altered pattern of mevalonate metabolism is associated with inhibition of protein isoprenylation in the cells. We named this ratio the inhibition of protein isoprenylation index (IPI index). The 10 analogs showed a wide range of IPI indices. Two analogs, S3 and S9 had effects similar to, or stronger than, canventol. Three analogs, C44, C46 and C47, with lower IPI indices, inhibited tumor promotion on mouse skin slightly less than canventol itself did. This study shows that inhibition of protein isoprenylation in the cells, indicated by an increase in the IPI index, is a new biomarker for estimating inhibition of tumor promotion.

Dominant expression of a 1.3 Mb human Ig kappa locus replacing mouse light chain production

Expression studies of multigene families, such as the immunoglobulin (Ig) loci, are difficult because of their large size and the necessity to introduce germline configured regions into an animal. Antibody diversity from Ig gene miniloci is limited by the number of variable (V) region genes and the need for distal regulatory elements to control expression. Here, we show germline transfer into mice of a 1300 kb human Ig kappa light chain locus on a yeast artificial chromosome that resulted in early DNA rearrangement and highly efficient human light chain expression. The human locus was assembled from a 300 kb authentic region using contig extension by addition of cosmid multimers to supplement the variable gene cluster. This resulted in the addition of about 100 V region genes in germline configuration from different families. In transgenic animals with Ig kappa disruption, this large human kappa locus replaced the endogenous locus, and subsequent down-regulation of Ig lambda light chain contribution led to a dominant expression of the rearranged human genes. Contrary to expectation, rather than providing a solely selective advantage for ensuring repertoire formation controlled by the sheer number of introduced genes, the lambda/kappa ratio in serum appears to be the result of competition for early surface Ig expression maintained in the developing B cell.-Zou, X., Xian, J., Davies, N. P., Popov, A. V., Brüggemann, M. Dominant expression of a 1.3 Mb human Ig kappa locus replacing mouse light chain production.

[The significance of circulating endothelial cell in hypoxic injury of pulmonary vascular endothelial cell]

OBJECTIVE

To observe the changes of vascular endothelial cell (VEC) in hypoxic rats and to check the damage of VEC in vivo, an experiment for observing circulating endothelial cells was conducted.

METHOD

Thirty male Wistar rats were classified into 5 groups in random, exposted to 10% O2 and 1% FeCl3 intraveniously. After 0, 1, 2, 3, 4 weeks, PaO2, circulating endothelial cells (CEC) were measured and the lung specimens, the pulmonary artery were examined by transmission electron micrography (TEM) and scanning electron micrography (SEM).

RESULTS

Lung specimens and pulmonary artery under TEM and SEM: swollen appeared to VEC after 1 week. As time prolonged, VEC appeared splitting, broken and peeled off. The amount of CEC increased as the time proceeding, the longer the time, the higher the number of the CEC. Obvious hypoxemia developed in the tested animals as the time prolonged.

CONCLUSIONS

All above results indicated: the time of anoxia proceeding, the structure of lung and pulmonary artery VEC were damaged obviously. The increase of CEC matched with the changes of ultrastructure of lung VEC. CEC specifically reflected the damage of VEC. Non-invasive measurement of CEC is valuble in evaluation of hypoxic injury of pulmonary VEC.