Clonality in wild rice (Oryza rufipogon, Poaceae) and its implications for conservation management

Correlations were examined between habitat characters and clonal structures determined by the RAPD (random amplified polymorphic DNA) assay in five populations of Oryza rufipogon in China. Nine of 175 decameric primers were used in the study because they reproducibly amplified polymorphisms. The extent of clonality together with the clonal and sexual reproductive strategies varied greatly among the five populations and correlated with the habitats where they occur. The populations under serious disturbance or seasonal drought tended to have small clones with relatively high clonal diversity caused by sexual reproduction, whereas the populations with little disturbance and sufficient supply of water were prone to have large clones with relatively low clonal variation and low sexual reproduction. Therefore, the dynamics of sexual vs. clonal reproduction of this species depended mainly on environmental factors, such as external disturbance and water supply, rather than latitudes indicated by previous study. These results have important implications for in situ conservation of O. rufipogon. Adequate external disturbance and water supply control are essential for maintaining high clone diversity of in situ conserved populations. According to the extent of clonality of the populations examined, we recommend that an interval of >12 m should be required for collecting samples for ex situ conservation and for population genetic studies to capture possible genetic diversity for O. rufipogon in China.

[Analyses of population genetic structure by using dominant markers]

Dominant markers tend to under-estimate the amount of genetic diversity relative to codominant systems when applying in population genetics. In order to compare various existing methods for analysis of genetic structure, RAPD markers were used to detect genetic variability of 5 populations of Oryza granulata from China. The results indicated that both Shannon index of diversity and Nei gene diversity were superior to percentage of polymorphic bands (PPB) because the latter lacked of ability to describe frequency difference of polymorphic bands. Mantel test showed significant relation (r > 0.95, t > t0.01) among matrice of 17 different genetic similarities, which indicated that all of them could be used in analysis of genetic relations of individuals of Oryza granulata. Both AMOVA analysis based on phi st distance and analysis of Nei's distance showed consistent results in defining relationship among the 5 populations, and Lynch-Milligan pruning should be used to improve the estimation of population parameters. All of AMOVA, Gst and Shannon diversity analyses obtained similar results with majority of genetic variation occurring between Yunnan and Hainan, and low levels of genetic diversity resided within regions and populations.

Boiler briquette coal versus raw coal: Part II--Energy, greenhouse gas, and air quality implications

The objective of this paper is to conduct an integrated analysis of the energy, greenhouse gas, and air quality impacts of a new type of boiler briquette coal (BB-coal) in contrast to those of the raw coal from which the BB-coal was formulated (R-coal). The analysis is based on the source emissions data and other relevant data collected in the present study and employs approaches including the construction of carbon, energy, and sulfur balances. The results show that replacing R-coal with BB-coal as the fuel for boilers such as the one tested would have multiple benefits, including a 37% increase in boiler thermal efficiency, a 25% reduction in fuel demand, a 26% reduction in CO2 emission, a 17% reduction in CO emission, a 63% reduction in SO2 emission, a 97% reduction in fly ash and fly ash carbon emission, a 22% reduction in PM2.5 mass emission, and a 30% reduction in total emission of five toxic hazardous air pollutant (HAP) metals contained in PM10. These benefits can be achieved with no changes in boiler hardware and with a relatively small amount of tradeoffs: a 30% increase in PM10 mass emission and a 9-16% increase in fuel cost.

Boiler briquette coal versus raw coal: Part I--Stack gas emissions

Stack gas emissions were characterized for a steam-generating boiler commonly used in China. The boiler was tested when fired with a newly formulated boiler briquette coal (BB-coal) and when fired with conventional raw coal (R-coal). The stack gas emissions were analyzed to determine emission rates and emission factors and to develop chemical source profiles. A dilution source sampling system was used to collect PM on both Teflon membrane filters and quartz fiber filters. The Teflon filters were analyzed gravimetrically for PM10 and PM2.5 mass concentrations and by X-ray fluorescence (XRF) for trace elements. The quartz fiber filters were analyzed for organic carbon (OC) and elemental carbon (EC) using a thermal/optical reflectance technique. Sulfur dioxide was measured using the standard wet chemistry method. Carbon monoxide was measured using an Orsat combustion analyzer. The emission rates of the R-coal combustion (in kg/hr), determined using the measured stack gas concentrations and the stack gas emission rates, were 0.74 for PM10, 0.38 for PM2.5, 20.7 for SO2, and 6.8 for CO, while those of the BB-coal combustion were 0.95 for PM10, 0.30 for PM2.5, 7.5 for SO2, and 5.3 for CO. The fuel-mass-based emission factors (in g/kg) of the R-coal, determined using the emission rates and the fuel burn rates, were 1.68 for PM10, 0.87 for PM2.5, 46.7 for SO2, and 15 for CO, while those of the BB-coal were 2.51 for PM10, 0.79 for PM2.5, 19.9 for SO2, and 14 for CO. The task-based emission factors (in g/ton steam generated) of the R-coal, determined using the fuel-mass-based emission factors and the coal/steam conversion factors, were 0.23 for PM10, 0.12 for PM2.5, 6.4 for SO2, and 2.0 for CO, while those of the BB-coal were 0.30 for PM10, 0.094 for PM2.5, 2.4 for SO2, and 1.7 for CO. PM10 and PM2.5 elemental compositions are also presented for both types of coal tested in the study.

Genetic erosion in northern marginal population of the common wild rice Oryza rufipogon Griff. and its conservation, revealed by the change of population genetic structure

In order to monitor genetic erosion within the northern marginal population of common wild rice Oryza rufipogon Griff. from Dongxiang, Jiangxi Province, China, allozyme diversity encoded by 22 loci was analyzed electrophoretically from all the existing subpopulations in 1980, 1985 and 1994. The sample collected from the nine large subpopulations in 1980 showed the highest levels of genetic diversity (A = 1.27, P = 18.20%, Ho = 0.042 and He = 0.049) and a slight deviation from Hardy-Weinberg expectation (F = 0.143), the sample from five moderate ones in 1985 displayed medium levels of genetic diversity (A = 1.14, P = 13.60%, Ho = 0.008 and He = 0.049) and a great deviation from Hardy-Weinberg expectation (F = 0.837), and the sample from two small ones in 1994 demonstrated the lowest levels of genetic diversity (A = 1.09, P = 9.10%, Ho = 0.000 and He = 0.043) and the largest deviation from Hardy-Weinberg expectation (F = 1.000). The results not only documented the genetic erosion stemmed from the extinction of the subpopulations, but also revealed the drastic change of the population genetic structure due to the reduction of the population. Finally, some conservation strategies for the population are proposed.

[Subcloning and sequencing of DNA fragment related to salt tolerance in Sinorhizobium meliloti 042B]

A 4 kb ClaI DNA fragment related to salt tolerance from S. meliloti 042B was digested by HindIII down 2.4 kb fragment, and a 1.6 kb ClaII-HindIII fragment was retained on plasmid pML122. Then, the 2.4 kb DNA fragment was ligated with plasmid pBBR1-MCS2, and the recombinant plasmid was transformed to E. coli DH5 alpha, and transformant GS2 was obtained. Three-parental mating experiments were carried out with transformant GS2 as donor, salt sensitive strains GZ17 as recipient and pRK2013 as helper plasmid, then the transconjugant GG2 was selected on FY plates containing kanamycin and 0.4 mol/L NaCl. The remaining DNA fragment was self ligated with pML122 and then transformed into E. coli S17-1 and transformat GS0 was obtained. Two-parental mating experiment was carried out with transformant GS0 as donor and salt sensitive strain GZ17 as recipient, but no transconjugant was obtained on the FY plates. Then, the 2.4 kb HindIII DNA fragment was ligated into sequencing vector pGEM-7Zf(+) for sequencing. The result of sequencing and analysis showed that the 2.4 kb DNA fragment contained three ORFs. According to the result of sequencing, further subcloning was conducted and 1.9 kb HindIII-Sac II DNA fragment related to salt tolerance was obtained.

Shear modulation force microscopy study of near surface glass transition temperatures

We report results of glass transition (T(g)) measurements for polymer thin films using atomic force microscopy (AFM). The AFM mode, shear modulation force microscopy (SMFM), involves measuring the temperature-dependent shear force on a tip modulated parallel to the sample surface. Using this method we have measured the surface T(g) of thin (17-500 nm) polymer films and found that T(g) is independent of film thickness (t>17 nm), strength of substrate interactions, or even presence of substrate.

Targeting angiogenesis inhibits tumor infiltration and expression of the pro-invasive protein SPARC

The solid growth of high-grade glioma appears to be critically dependent on tumor angiogenesis. It remains unknown, however, whether the diffuse infiltration of glioma cells into healthy adjacent tissue is also dependent on the formation of new tumor vessels. Here, we analyze the relationship between tumor angiogenesis and tumor cell infiltration in an experimental glioma model. C6 cells were implanted into the dorsal skinfold chamber of nude mice, and tumor angiogenesis was monitored by intravital fluorescence videomicroscopy. Glioma infiltration was assessed by the extent of tumor cell invasion into the adjacent chamber tissue and by expression of SPARC, a cellular marker of glioma invasiveness. To test the hypothesis that glioma angiogenesis and glioma infiltration are codependent, we assessed tumor infiltration in both the presence and the absence of the angiogenesis inhibitor SU5416. SU5416 is a selective inhibitor of the VEGF/Flk-1 signal-transduction pathway, a critical pathway implicated in angiogenesis. Control tumors demonstrated both high angiogenic activity and tumor cell invasion accompanied by strong expression of SPARC in invading tumor cells at the tumor-host tissue border. SU5416-treated tumors demonstrated reduced vascular density and vascular surface in the tumor periphery accompanied by marked inhibition of glioma invasion and decreased SPARC expression. A direct effect of SU5416 on glioma cell motility and invasiveness was excluded by in vitro migration and invasion assays. These results suggest a crucial role for glioma-induced angiogenesis as a prerequisite for diffuse tumor invasion and a possible therapeutic role for anti-angiogenic compounds as inhibitors of both solid and diffuse infiltrative tumor growth.

Targeting angiogenesis inhibits tumor infiltration and expression of the pro-invasive protein SPARC

The solid growth of high-grade glioma appears to be critically dependent on tumor angiogenesis. It remains unknown, however, whether the diffuse infiltration of glioma cells into healthy adjacent tissue is also dependent on the formation of new tumor vessels. Here, we analyze the relationship between tumor angiogenesis and tumor cell infiltration in an experimental glioma model. C6 cells were implanted into the dorsal skinfold chamber of nude mice, and tumor angiogenesis was monitored by intravital fluorescence videomicroscopy. Glioma infiltration was assessed by the extent of tumor cell invasion into the adjacent chamber tissue and by expression of SPARC, a cellular marker of glioma invasiveness. To test the hypothesis that glioma angiogenesis and glioma infiltration are codependent, we assessed tumor infiltration in both the presence and the absence of the angiogenesis inhibitor SU5416. SU5416 is a selective inhibitor of the VEGF/Flk-1 signal-transduction pathway, a critical pathway implicated in angiogenesis. Control tumors demonstrated both high angiogenic activity and tumor cell invasion accompanied by strong expression of SPARC in invading tumor cells at the tumor-host tissue border. SU5416-treated tumors demonstrated reduced vascular density and vascular surface in the tumor periphery accompanied by marked inhibition of glioma invasion and decreased SPARC expression. A direct effect of SU5416 on glioma cell motility and invasiveness was excluded by in vitro migration and invasion assays. These results suggest a crucial role for glioma-induced angiogenesis as a prerequisite for diffuse tumor invasion and a possible therapeutic role for anti-angiogenic compounds as inhibitors of both solid and diffuse infiltrative tumor growth.

Allozyme diversity and population genetic structure of Pinus densata Master in northwestern Yunnan, China

We investigated the levels and patterns of genetic diversity of Pinus densata Master in Yunnan. Horizontal starch-gel electrophoresis was performed on macrogametophytes collected from nine populations in northwestern Yunnan, China. Compared with other gymnosperm species, P. densata has higher mean values for all measures of genetic diversity. Allozyme polymorphism (0.99 criterion) was 97.0% and 71.4% at the species and population levels, respectively. The average number of alleles per locus was 3.1 and 2.0 at the species and population levels. Mean expected heterozygosity was substantially higher in P. densata than average values investigated for other gymnosperms both at the population (Hep = 0.174 +/- 0.031) and at the species (Hes = 0.190) levels. Of the total genetic variation, less than 12% was partitioned among populations (GST = 0.112). Our allozyme survey supports the suggestion that the observed higher diversity in P. densata may be attributed partly to its hybrid origin between two genetically distinct species, P. yunnanensis and P. tabulaeformis. In addition, we suggest that introgression would give rise to the increase in genetic diversity occurring in P. densata.

Carboxyamido-triazole induces apoptosis in bovine aortic endothelial and human glioma cells

Carboxyamido-triazole (CAI), an inhibitor of non-voltage-gated calcium channels, has been studied in Phase I/II clinical trials following the identification of its inhibitory effects on tumor cell invasion and motility. It has also been reported to inhibit human endothelial cell proliferation, migration, and adhesion to the basement membrane. In glioma, biological assays have shown CAI to be active in inhibiting the phenotypes of invasion and angiogenesis. The exact mechanism of action is not clearly understood, although it appears to work via inhibition of calcium influx in several signal transduction pathways that inhibit cell cycle progression. Recent evidence implicates apoptosis as a contributing mechanism of chemotherapy-induced tumor cytotoxicity. Therefore, we studied the effects of CAI on apoptosis in bovine aortic endothelial cells and a human glioma cell line (U251N) using a variety of methods, including: (a) cell morphology; (b) terminal deoxynucleotidyl transferase-mediated nick end labeling analysis of in situ DNA strand breaks; (c) agarose gel electrophoresis to visualize DNA fragmentation; and (d) flow cytometry. Here we report that the kinetics of CAI-induced apoptosis in bovine aortic endothelial cells and glioma cells was determined to be both dose and time dependent in micromolar concentrations achievable in brain tissue in vivo.

In situ atomic force microscopic observation of albumin adsorption onto phase-separated organosilane monolayer surface

A mixed (n-octadecyltrichlorosilane (OTS)/[2-(perfluorooctyl)ethyl]trichlorosilane (FOETS)) monolayer was prepared on the water subphase and was subsequently immobilized onto the silicon wafer surface by chemical bonds. Atomic force microscopic (AFM) observation of the mixed (OTS/FOETS) monolayer revealed the formation of a phase-separated structure. In situ AFM observation of the adsorption behavior of bovine serum albumin (BSA) onto the mixed (OTS/FOETS) monolayers, successfully showed the adsorption behavior of BSA onto the phase-separated surface. It also revealed that in the case of pH 7.5, BSA was preferentially adsorbed onto the lower surface free energy FOETS phase of the mixed (OTS/FOETS) monolayer. On the other hand, BSA was adsorbed homogeneously onto the OTS and FOETS phases at the isoelectric point of BSA (pI 4.7). These results indicate that the preferential adsorption of BSA onto the FOETS phase in the mixed (OTS/FOETS) monolayer system may be due to: (1) the minimization of interfacial free energy between a monolayer surface and an aqueous solution; and (2) the electrostatic repulsion among BSA molecules bearing negative charges.

[Characteristics of producing-fumonisin and dimorphic fungus of fusarium moniliforme]

OBJECTIVE

To study the carcinogenesis of fusarium moniliforme and its fumonisins in animals.

METHODS

The producing-fumonisin and dimorphic fungus pathogenicity of F. moniliforme from Zhejiang, China were identified and characterized.

RESULTS

The F. moniliforme isolated from foodstuffs was shown to produces fumonisin B(1) > 400 microg/g in medium by IC-ELISA. Ten foodstuffs samples showed (2% - 100%) detection rate of F. moniliforme and contained fumonisin B(1) between (3.7 - 143.1) microg/g. The strains of F. moniliforme formed yeast-like colony in Sabouraud's agar plates contained 9% NaCl at 37degrees C incubator and budding multiplication mostly. In blood agar plates the strains of F. moniliforme showed grass green haemolytic reactions.

CONCLUSION

It is important to carry out (or to perform) oulepidemiologicol survey of F. moniliforme as a primary pathogenic fungus, as well as the mycotoxins of F. moniliforme in vitro.

Identification and localization of the cytokine SDF1 and its receptor, CXC chemokine receptor 4, to regions of necrosis and angiogenesis in human glioblastoma

Glioblastoma multiforme (GBM) tumors display extensive histomorphological heterogeneity, with great variability in the extent of invasiveness, angiogenesis, and necrosis. The identification of genes associated with these phenotypes should further the molecular characterization, permitting better definition of glioma subsets that may ultimately lead to better treatment strategies. Therefore, we performed a differential mRNA display analysis comparing six GBM-derived primary cell cultures from patients having tumors with varied histomorphological features. We identified stromal cell-derived factor 1 (SDF1) as a gene with varied expression. SDF1 (cytokine) and CXC chemokine receptor 4 (CXCR4) interactions are implicated in modulating cell migration. They are also implicated in modulating the immune response in AIDS patients by macrophage-mediated T-cell apoptosis. GBM patients also fail to mount an immune response, although their tumors are seemingly exposed to immune cells in regions of angiogenesis, where the blood-brain barrier is absent, or in areas of necrosis. To determine whether the expression and localization of SDF1 and CXCR4 are consistent with such a role in these brain tumors, immunohistochemical analyses of these proteins were performed on normal brain and astrocytomas (grades II-IV). In normal brain tissue, low levels of SDF1 (0.5+) were observed in astrocytic processes, in neurons, and in the occasional phagocytic cells around vessels. CXCR4 expression was negative in brain tissue but was observed in phagocytic cells within the vessel lumen. In tumors, SDF1 and CXCR4 expression was colocalized when both were expressed, and SDF1 and CXCR4 expression increased with increasing tumor grade (from 0.5+ to 6+). Additionally, CXCR4 was expressed in neovessel endothelial cells. The proteins were expressed in regions of angiogenesis and degenerative, necrotic, and microcystic changes. Those tumors displaying greater amounts of these features had greater staining intensity of the proteins. The expression of SDF1 and CXCR4 did not colocalize with the proliferation marker MIB-1. Thus, our data suggest that SDF1 and CXCR4 expressions: (a) increase with increasing grade; (b) colocalize to regions within these tumors where their interaction may contribute to angiogenesis and/or modulation of the immune response; and (c) may serve to characterize subsets of GBMs.

Phylogeny of rice genomes with emphasis on origins of allotetraploid species

The rice genus, Oryza, which comprises 23 species and 9 recognized genome types, represents an enormous gene pool for genetic improvement of rice cultivars. Clarification of phylogenetic relationships of rice genomes is critical for effective utilization of the wild rice germ plasm. By generating and comparing two nuclear gene (Adh1 and Adh2) trees and a chloroplast gene (matK) tree of all rice species, phylogenetic relationships among the rice genomes were inferred. Origins of the allotetraploid species, which constitute more than one-third of rice species diversity, were reconstructed based on the Adh gene phylogenies. Genome types of the maternal parents of allotetraploid species were determined based on the matK gene tree. The phylogenetic reconstruction largely supports the previous recognition of rice genomes. It further revealed that the EE genome species is most closely related to the DD genome progenitor that gave rise to the CCDD genome. Three species of the CCDD genome may have originated through a single hybridization event, and their maternal parent had the CC genome. The BBCC genome species had different origins, and their maternal parents had either a BB or CC genome. An additional genome type, HHKK, was recognized for Oryza schlechteri and Porteresia coarctata, suggesting that P. coarctata is an Oryza species. The AA genome lineage, which contains cultivated rice, is a recently diverged and rapidly radiated lineage within the rice genus.

The experience in the treatment of patients with extensive full-thickness burns

The aim of the present study is to analyze the changes of cure rate and the main causes of death in the last 40 years, and to summarize our experience in the treatment of extensive full-thickness burn patients. The clinical characteristics, cure rate and main causes of death of 73 cases with total burned area more than 90% TBSA and full-thickness burn area more than 70% TBSA were analyzed retrospectively. Among them, 21 cases (28.8%) were cured and 52 cases (71.2%) died. The cure rate increased significantly in the recent years, and the main causes of death changed from shock and sepsis in the time period 1959-1978 to sepsis and MODS in the past two decades. Due to the improvement of early comprehensive management of burn shock, aggressive surgical approach to full-thickness burn wound and potent systemic supporting measures, the survival rate increased significantly.

Chronic epilepsy in developing hippocampal neurons: electrophysiologic and morphologic features

Despite the susceptibility of immature neurons to seizures, there are few models of epilepsy in the developing brain. By taking advantage of activity-dependent developmental changes in young neurons, we have developed a novel model of chronic epilepsy in cultured hippocampal slices. Incubating slices in tetrodotoxin (TTX) for at least 1 week produced significant changes in the electrical activity and appearance of CA1 pyramidal neurons. Extracellular recordings revealed multiple population spikes, and, in whole-cell recordings, evoked synaptic potentials lasting hundreds of milliseconds with many superimposed action potentials were present. Spontaneous firing with burst-like discharges was also evident. These changes were secondary to increased AMPA-receptor-mediated responses and decreased GABA(A) receptor events. Altered membrane properties involved increased expression of T-type Ca(2+) channels which are normally down-regulated in these neurons. TTX-treated neurons also showed abnormal dendritic branching. This model of chronic epilepsy in developing hippocampal neurons demonstrated many changes at the membrane, cellular and synaptic level that may provide new insights into the nature of epileptogenesis in the young brain.

Treatment of severe electrical burns

In summary, electrical injury is a typical type of burn injury with a unique mechanism of systemic and local damage. Resuscitation is more complex in critical patients than that of thermal injury. Local management is more difficult, which could be eventually accomplished by sequential procedures of debridement and operation. Although the modern trend of performing early debridement and operation might be promising, traditional experiences are still being used in clinical care. Progress in clinical management has brought about an improvement in therapeutic outcome, resulting in a decrease of amputation rate and reduced disability. Some typical types of electrical injury demand special treatment, which might prove to be effective. Close observation and timely treatment of the injury itself and related complications will be lifesaving in caring for critical electrical injury. Some special therapeutic measures would be indicated and might be fruitful in proving their efficacy. New measures aimed at theoretical problems will be promising if electroporation could be effectively treated.

Increased SPARC expression promotes U87 glioblastoma invasion in vitro

Our recent studies have focused on identifying invasion-promoting genes that are expressed early in brain tumor progression. We identified and characterized SPARC (secreted protein acidic and rich in cysteine) as a potential candidate. To determine whether increased SPARC expression functionally promotes brain tumor invasion, SPARC was transfected into U87MG glioblastoma cells using the tetracycline-off gene expression system. The parental cell line (U87MG), the parental transactivator-transfected clone (U87T2) and three selected U87T2-SPARC-transfected clones (A2bi, A2b2 and C2a4) were characterized for endogenous and transfected SPARC expression. In comparison to the parental or U87T2 cell lines, the SPARC-transfected clones demonstrated: (1) morphological changes, (2) increased SPARC transcript and protein abundances that were down-regulated by the tetracycline analog doxycycline, (3) perinuclear localization of the transfected SPARC (consistent with reported localization of SPARC in normal cells in culture) and (4) altered adhesion and increased invasion as assessed by the spheroid confrontation assay. These data indicate that increased SPARC expression contributes to U87 glioblastoma tumor invasion in vitro and that these cell lines will serve as useful reagents to investigate the mechanism(s) by which SPARC promotes this phenotype in vitro and in vivo.

RAPD variation within and between natural populations of the wild rice oryza rufipogon from china and brazil

Genetic variation within and between eight natural populations of Oryza rufipogon from China and Brazil was investigated at the DNA level by analysis of RAPD fragments. Out of 60 random primers, which were initially screened against DNA from four individuals, 20 generated highly reproducible RAPD fragments which were then used for further population analysis. With these primers, 95 discernible DNA fragments were produced and 78 (82.1%) were polymorphic, which indicated that high levels of genetic variation existed in these natural populations. In addition, the Chinese populations showed greater polymorphism than those from Brazil at both the population and regional levels. This is noteworthy considering that the Chinese populations are from a relatively restricted area of China. The factors responsible for these findings include the contrasting mating systems in the Brazilian and Chinese populations, and gene flow from annual cultivated rice to perennial natural populations in China. An Analysis of Molecular Variance (AMOVA) was used to apportion the variation between individuals within populations, between populations within regions, and between regions. Results showed that 61.8% of the total genetic diversity resided between the two continents, whereas only 14.9% and 23.3% was attributable to population differences within regions and to individual differences within a population, respectively. The great genetic differentiation between the Chinese and Brazilian populations is in agreement with recent treatment of the American form of O. rufipogon as a separate species, O. glumaepatula.

Reduction of the parahippocampal gyrus and the hippocampus in patients with chronic schizophrenia

BACKGROUND

There have been many studies reporting reduced volume of the hippocampus or other limbic structures in patients with schizophrenia, but the literature is inconsistent.

AIMS

To compare patients with either first-episode or chronic schizophrenia with controls using high-resolution volumetric magnetic resonance imaging (MRI) scans.

METHOD

Thirteen patients with first-episode schizophrenia, 27 with chronic schizophrenia and 31 controls had 1.5 mm coronal slices taken through the whole brain using a spoiled-grass MRI acquisition protocol.

RESULTS

The parahippocampal gyrus was reduced significantly on the left side in patients with chronic schizophrenia compared with controls for both male and female patients, whereas the hippocampus was reduced significantly on both sides only in female patients. There were no significant reductions in any structure between patients with first-episode schizophrenia and controls.

CONCLUSIONS

Volumetric reduction seen in patients with chronic schizophrenia may be due to an active degenerative process occurring after the onset of illness.

SPARC: a potential diagnostic marker of invasive meningiomas

SPARC, a secreted, extracellular matrix-associated protein implicated in the modulation of cell adhesion and migration, was evaluated as a marker for invasive meningiomas. Although the majority of meningiomas are clinically and morphologically benign, approximately 10% progress into atypical and malignant tumors, according to the standard criteria. However, a subset of meningiomas presents as histomorphologically benign tumors (WHO grade I), but they are clinically invasive. It has been suggested that these tumors should be classified as malignant, and that the patients may require adjuvant therapy and closer follow up. Unfortunately, a significant number of these tumors may not be recognized because the surgical specimen used to assess the grade of a tumor lacks the infiltrative interface with the brain, which is currently necessary to determine its invasive character. Therefore, a marker of heightened invasiveness would greatly facilitate the identification of this subset of patients. In this study, the immunohistochemical expression of SPARC in benign, noninvasive primary meningiomas was compared with its expression in invasive, aggressive, primary and recurrent meningiomas. SPARC was not expressed in the 9 benign, noninvasive tumors, but was highly expressed in the 20 invasive tumors, regardless of the grade. The findings suggest that SPARC is a potential diagnostic marker of invasive meningiomas and is capable of distinguishing the histomorphologically benign noninvasive from the histomorphologically benign but invasive meningiomas, in the absence of the infiltrative interface.

Association of brain structural change with the heterogeneous course of schizophrenia from early childhood through five years subsequent to a first hospitalization

Fifty first-episode patients with schizophrenia were followed for 5 years subsequent to their first hospitalization. The course of illness was charted prospectively and premorbid childhood histories were obtained retrospectively at the initial evaluation, and MRI scans were obtained initially and at each follow-up. Fifteen different life-time patterns of illness course emerged, although none were specifically associated with structural brain change. A deterioration in premorbid scores was positively correlated with larger ventricular volume at the first hospitalization, and the larger the ventricles, the less the subsequent change in ventricular size thereafter. An analysis to see whether initial hemispheric and ventricular size could predict different course types only revealed that patients with an acute onset and complete recovery had significantly smaller ventricles than all others. No differences emerged for initial hemispheric size. Thirty-four percent of patients individually showed some association of brain ventricular size and 28% hemisphere volume reductions with fluctuation in psychotic symptoms. Paradoxically, most showed larger ventricles and smaller hemispheres to be associated with clinical improvement, rather than the predicted reverse. These latter data question the notion that the structural brain changes seen over time in some patients are related to poor outcome, although small ventricular size in those patients with acute onset may be predictive of recovery. Thus, brain structural change is occurring early in the course of illness and may be a consequence of the process leading to resolution.

SPARC: a signal of astrocytic neoplastic transformation and reactive response in human primary and xenograft gliomas

In an attempt to identify genetic alterations occurring early in astrocytoma progression, we performed subtractive hybridization between astrocytoma and glioblastoma cDNA libraries. We identified secreted protein acidic and rich in cysteine (SPARC), a protein implicated in cell-matrix interactions, as a gene overexpressed early in progression. Northern blot and immunohistochemical analyses indicated that transcript and protein were both elevated in all tumor specimens (grades II-IV) examined when compared with levels in normal brain. The level of SPARC expression was found to be tumor-dependent rather than grade-related. Immunohistochemically, SPARC protein was found to be overexpressed in 1) cells in the less cellularly dense regions within the tumor mass, 2) histomorphologically neoplastic-looking cells in adjacent normal brain at the tumor/brain interface, 3) neovessel endothelial cells in both the tumor and adjacent normal brain, and 4) reactive astrocytes in normal brain adjacent to tumor. Using a combination of DNA in situ hybridization and protein immunohistochemical analyses of the human/rat xenograft, SPARC expression was observed in the human glioma cells within the tumor mass, and in cells that invaded along vascular basement membranes and individually into the rat brain parenchyma, suggesting it may be an invasion-related gene. While it remains to be determined whether SPARC functionally contributes to tumor cell invasion, these data suggest that the early onset of increased SPARC expression, though complex, may serve as a signal indicative of neoplastic astrocytic transformation and reactive response to tumor-induced stress.

Three-dimensional surface area of the aortic valve orifice by three-dimensional echocardiography: clinical validation of a novel index for assessment of aortic stenosis

BACKGROUND

A direct and accurate method of assessing aortic valve area (AVA) in patients with aortic stenosis (AS) is desirable because of the well-known theoretical and practical limitations of the currently available methods. We assessed the clinical feasibility and accuracy of a novel index, the 3-dimensional surface area (3-DSA) of the aortic valve orifice by 3-dimensional transesophageal echocardiography (3-DTEE) in patients with AS.

METHODS

Intraoperative 3-DTEE was performed in 23 consecutive patients (mean age 58 +/- 15 years) with valvular AS using a Toshiba SSA-380A system with a multiplane TEE probe and a TomTec EchoScan system. The 3-DTEE acquisition, processing and reconstruction were conducted and the aortic valve orifice presented using a "surgeon's aortotomy view" (aortic valve orifice as if viewed through an open aortic root). The 3-D images were videotaped and calibrated and the 3-DSA measured by planimetry of the inner surface of the aortic valve leaflets at the maximal systolic opening using the dynamic 3-D images. For comparison, the 2-D cross sectional area (2-DCSA) of the aortic valve was also determined by 2-DTEE. The 3-DSA and 2-DCSA were compared with the AVA by the invasive Gorlin formula and the Doppler continuity equation method by transthoracic echocardiography.

RESULTS

The 3-DSA and 2-DCSA measurements were feasible in all but one patient. Both 3-DSA and 2-DCSA correlated moderately well with the AVA by the Gorlin formula (n = 17, r = 0.66, standard error of the estimate [SEE] = 0.3 cm2, P <.05 for 3-DSA and r = 0.61, SEE = 0. 5 cm2 P <.05 for 2-DCSA, respectively). They also correlated well with the AVA by Doppler continuity equation method (n = 22, r = 0.90, SEE = 0.1 cm2, P <.05 for 3-DSA and r = 0.83, SEE = 0.3 cm2, P <.05 for 2-DCSA, respectively). There was no statistically significant difference between the 3-DSA and AVA by both the Gorlin formula (Delta = 0.1 +/- 0.3 cm2, P =.3) and the Doppler continuity equation (Delta = -0.0 +/- 0.3 cm2, P =.7). In contrast, the 2-DCSA significantly overestimated AVA by the Gorlin formula (Delta = 0.5 +/- 0.5 cm2, P <.005) and by the Doppler continuity equation (Delta = 0.5 +/- 0.6 cm2, P <.0001).

CONCLUSIONS

Planimetry of 3-DSA of the aortic valve orifice by 3-DTEE is a clinically feasible and relatively accurate technique for assessment of AVA and is superior to 2-DCSA by 2-DTEE.

[The inhibiting effect of glycyrrhizin on proliferation of the mice submandibular gland fibrosarcoma cell line in vitro]

OBJECTIVE

To study the inhibiting effect of glycyrrhizin on proliferation of the cell line of mice submandibular gland fibrosarcome in vitro.

METHODS

Light and electronic microscope examination, proliferative state of cells and cycle phase analysis were used.

RESULTS

Administration of glycyrrhizin above 600 mg/L could inhibit cell proliferation, and the effect was dose and time dependent. The morphological change of the cell line affected by glycyrrhizin could be seen with light and electronic microscope. Cell cycle phase analysis showed gLy-cyrrhizin gould stop cells shifting from G1 to S phase.

CONCLUSION

The Lowest inhibition concentration of glycyrrhizin to the cell line was above 600 mg/L, The antineoplastic effect of glycyrrhizin was possibly accomplished by interfering metabolism of G1 phase cells or/and blocking initiation of DNA synthesis.

[Effect of CD11b/CD18 on burn-activated PMN-mediated permeability of pulmonary microvascular in isolated perfused lung]

OBJECTIVE

To determine the effect of intercellular adhesion molecule (ICAM-1) CD11b/CD18 in burn-activated PMN-mediated permeability of microvascular in isolated perfused lung.

METHOD

Isolated lungs were distributed into 7 groups according to the different contents of perfused fluid: normal perfused fluid, normal rat serum, burn rat serum, normal rat PMN, burn rat PMN, normal rat PMN blocked by monoclonal antibody to adhesion molecule CD11b/CD18 and burn rat PMN blocked by antibody. The extent of isolated lung edema, vascular permeability to small molecules (fluid) and vascular permeability to large molecules (albumin) were expressed by lung weight gain (LWG), fluid filtration coefficient (Kf) and pulmonary albumin permeability-surface area product (PS) respectively.

RESULT

Burn serum could increase LWG, Kf PS, so did burn-activated PMN. The latter could make PS increase more obviously. Monoclonal antibody to CD11b/CD18 on PMN could obviously decrease PMN sequestration in isolated perfused lung. The protective effect of antibody on increasing LWG and Kf, and particularly PS was demonstrated.

CONCLUSION

(1) The effect of mediators from burn-activated PMN to EC was mediated by PMN adhesion to EC. (2) Some mediators from burn-activated PMN increase mainly the pulmonary vascular permeability to small molecules, and PMN adhesion to EC mediated by CD11b/CD18 may increase directly the permeability to large molecules. (3) Adhesion molecule CD11b/CD18 perhaps have an ability to regulate directly EC by combining its receptor ICAM-1 on EC.

[The effect of PMN adhesion mediated by CD11b/CD18 on the increasing permeability of microvascular endothelial monolayer after severe burn injury]

OBJECTIVE

To detect the effect of burn-activated PMN adhesion and its adhesion molecule CD11b/CD18 on microvascular endothelial permeability using an experimental model of endothelial monolayer on polycarbonate microporous filters.

METHODS

An experimental model for in vitro study of endothelal monolayer for permeability analysis was established. Seven groups were divided into according to the treatment of microvascular endothelial monolayer. Fluid filtration coeffecient(Kf) and albumin reflection coeffecient(delta) were measured after endothelial monolayer was perfused with albumin labelled by FITC.

RESULTS

Burn-activated PMN could increase the level of fluid filtration coeffecient(Kf) and decrease the albumin reflection coeffecient(delta). Monoclonal antibody sealing off CD11b/CD18 on PMN provented the change of delta induced by burn-activated PMN. Another microporous filter interposed between PMNs and endothelial monolayer corrected the changes of Kf and delta.

CONCLUSION

The permeability enhancing effect of PMNs may be attributed mainly to the PMN-EC adhesion mediated by CD11b/CD18. Blocking the PMN-EC over-adhesion in moderation may be helpful in reducing the lung injury due to severe burn injury.

Bovine serum albumin adsorption onto immobilized organotrichlorosilane surface: influence of the phase separation on protein adsorption patterns

Octadecyltrichlorosilane (OTS) and [2-(perfluorooctyl)ethyl]trichlorosilane (FOETS) monolayers and their mixed monolayer were polymerized on a water subphase and subsequently immobilized onto a silicon wafer surface by covalent bonding. Atomic force microscopic (AFM) observation of the mixed (OTS/FOETS) monolayer revealed the formation of a phase-separated structure. Protein-adsorption behavior onto the monolayers was investigated in situ on the basis of an attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectroscopic flow cell method and the morphology of the monolayer surface-adsorbed bovine serum albumin (BSA) was observed by AFM. Protein adsorption behavior observed by ATR-FT-IR flow cell method revealed that the amount of BSA adsorption onto the OTS and FOETS monolayers increased remarkably at an initial experimental stage and attained a steady state within a few minutes at pH 7.5. The amount of steady state adsorption was c. 0.18-0.2 microgcm(-2). AFM observation of the monolayer after exposure to BSA solution suggested that BSA adsorbed in the end-on adsorption state on OTS monolayer and side-on one in the FOETS monolayer, respectively. However, in the case of the mixed (OTS/FOETS) monolayer, ATR-FT-IR flow cell experiment revealed that the amount of steady state adsorption of BSA was suppressed. Also, AFM observation revealed that at pH 7.5, BSA preferentially adsorbed onto the FOETS phase of the mixed (OTS/FOETS) monolayer, which had a higher interfacial free energy against water. On the other hand, BSA adsorbed homogeneously onto the OTS and FOETS phases at the isoelectric point of BSA (pH 4.7). These results indicate that the preferential adsorption of BSA onto the FOETS phase in the mixed (OTS/FOETS) monolayer system is due to: (1) the minimization of the interfacial free energy between a monolayer surface and an aqueous solution; and (2) the electrostatic repulsion between BSA molecules bearing negative charges.

[Effects of endogenous TGF-beta during wound healing]

OBJECTIVE

To study the application of exogenous TGF-beta to excision, incision and burn wounds accelerating wound healing.

METHODS

The expression of endogenous TGF-beta during burn wound healing was observed by mRNA dot blot hybridization and immunohistochemistry, respectively.

RESULTS

Thermal injury could induce TGF-beta gene expression in cutaneous wounds. Expression level of TGF-beta mRNA increased over time to reach a peak around day 5 postburn, and declined at day 10 after thermal injury. Immunohistochemistry evidences indicated spatially and temporally that TGF-beta peptide mainly distributed at hair follicles and migrating epidermis at early and middle stages of repair process, and stronger immunoreactivity from days 5 to 10 after wound, which was directly proportional to epidermal cell migration and dermal fibroblast proliferation.

CONCLUSION

The expression models of TGF-beta protein and gene suggests that TGF-beta play a critical role in regulation of repair process. Whether the inhibition of expression and overexpression of TGF-beta is correlated to imparied repair and scar formation remains to be studied.

Feasibility, accuracy, and incremental value of intraoperative three-dimensional transesophageal echocardiography in valve surgery

In this prospective trial, intraoperative 2-dimensional (2-D) and 3-dimensional (3-D) transesophageal echocardiography (TEE) examinations were performed on 60 consecutive patients undergoing cardiac valve surgery. Both 2-D (including color flow and Doppler data) and 3-D images were reviewed by blinded observers, and major valvular morphologic findings recorded. In vivo morphologic findings were noted by the surgeon and all explanted valves underwent detailed pathologic examination. To test reproducibility, 6 patients also underwent 3-D TEE 1 day before surgery. A total of 132 of 145 attempted acquisitions (91%) were completed with a mean acquisition time of 2.8 +/- 0.2 minutes. Acquisition time was significantly shorter in patients with regular rhythms. Reconstructions were completed in 121 of 132 scans (92%) and there was at least 1 good reconstruction in 56 of 60 patients (93%). Mean reconstruction time was 8.6 +/- 0.7 minutes. Mean effective 3-D time, which was the time taken to complete an acquisition and a clinically interpretable reconstruction, was 12.2 +/- 0.8 minutes. Intraoperative 3-D echocardiography was clinically feasible in 52 patients (87%). Three-D echocardiography detected most of the major valvular morphologic abnormalities, particularly leaflet perforations, fenestrations, and masses, confirmed on pathologic examination. Three-D echocardiography predicted all salient pathologic findings in 47 patients (84%) with good quality images. In addition, in 15 patients (25%), 3-D echocardiography provided new additional information not provided by 2-D echocardiography, and in 1 case, 3-D echocardiographic findings resulted in a surgeon's decision to perform valve repair rather than replacement. In several instances, 3-D echocardiography provided complementary morphologic information that explained the mechanism of abnormalities seen on 2-D and color flow imaging. In the reproducibility subset, preoperative and intraoperative 3-D imaging detected a similar number of findings when compared with pathology. Thus, in routine clinical intraoperative settings, 3-dimensional TEE is feasible, accurately predicts valve morphology, and provides additional and complementary valvular morphologic information compared with conventional 2-D TEE, and is probably reproducible.

Morphology and dynamic change of discrete subaortic stenosis can be imaged and quantified with three-dimensional transesophageal echocardiography

This report describes three-dimensional transesophageal echocardiographic findings in three consecutive patients with discrete subaortic stenosis. The discrete subaortic stenosis lesions included a circumferential, a remnant crescent, and a broken fibrotic subaortic membrane. The lesions were best imaged by using a three-dimensional transesophageal echocardiography-generated "aortotomy view" of the left ventricular outflow tract immediately below the plane of the aortic valve. The three-dimensional images correlated well with surgical and pathologic findings. The three-dimensional surface areas of the left ventricular outflow tract at the level of discrete subaortic stenosis during systole (0.8 +/- 0.5 cm2) and diastole (1.7 +/- 0.7 cm2) were measured by planimetry of the three-dimensional transesophageal echocardiographic images. The novel "aortotomy view" offered by three-dimensional transesophageal echocardiography provided direct visualization and quantification of discrete subaortic stenosis in a dynamic fashion. In summary, three-dimensional transesophageal echocardiography can accurately display and quantify discrete subaortic stenosis and could be a new clinically useful tool for assessing discrete subaortic stenosis and guiding surgical and transcatheter interventions.

[Experimental study of temporal expression of endogenous TGF alpha in partial thickness scalded wounds]

Investigating spatial and temporal expression and distribution of endogenous TGF alpha, and clarifying its role in burn wound healing. Immunohistochemical and mRNA dot blot hybridization approaches were adopted. Thermal injury can induce TGF alpha gene expression. The expression peaks at the time when repair cells migrate and proliferate most actively, and declines on near completion of epithelialization. Otherwise, the mRNA expression of EGF receptor manifests the same change as TGF alpha's. Immunohistochemical investigation indicates that TGF alpha is mainly distributed in the survived hair follicles and reepithelialized cell layers, and the immunoreactive staining is proportional to epidermal cell growth and migration. Thermal injury can induce endogenous TGF alpha and EGF receptor expression, which is well controlled and correlated with the migration and proliferation of keratinocytes. Endogenous TGF alpha plays a positive role in regulation of wound healing.

[The role of PMN CD11b/CD18 on the increasing PMN adhesion to endothelial cells induced by severe burn injury]

The process of leukocyte adhesion was mediated by the intercellular adhesion molecular. In this study, both the influence of burn serum on the expression of PMN CD11b/CD18 and the role of CD11b/CD18 on the burn serum stimulated PMN adhesion to endothelial cells (EC) were investigated. The expression of CD11b/CD18 on PMN incubated with burn serum for 2 hours was increased obviously. So was PMN adhesion to EC. Monoclone antibody to PMN CD11b/CD18 could reduce the normal PMN adhesion to EC by half and block the increasing PMN adhesion induced by burn serum. These indicated that PMN CD11b/CD18 may be the main adhesion molecular participating in the increasing PMN adhesion to EC due to severe burn.

Expression of endogenous transforming growth factor-beta and its type I and type II receptors in rat burn wounds

Transforming growth factor-beta is a potent regulator of numerous processes in wound healing. These biological activities require the interaction of the growth factor with two classes of cell surface receptors, namely the type I and type II receptors. To understand the role of transforming growth factor-beta in burn wound healing, we undertook a study to localize this growth factor and its cell surface receptors within dermal burn wounds. Partial-thickness burn injuries were made on the backs of Wistar rats. At 1, 3, 5, 7, 10, 15, and 20 days after burning, samples of wounded and control skin were removed for the isolation of total RNA and immunohistochemistry. Thermal injury induced the expression of mRNA for transforming growth factor-beta and both type I and type II receptors. The expression of transforming growth factor-beta peaked 5 to 7 days after injury, then gradually declined. Of note, the expression of the transforming growth factor-beta receptors returned to normal before the expression of the growth factor. Immunohistochemical analysis showed that transforming growth factor-beta protein levels paralleled mRNA expression, and the protein was primarily localized to the migrating epidermal cells and dermal fibroblasts. The differences between the expression of transforming growth factor-beta and its receptors in the later stages of healing thermal injuries suggests the presence of a well-controlled mechanism to limit the effect of the growth factor on repair cells.

[Effect of dietary arginine on peripheral blood Th/Ts ratio and survival rate in severe burned rats]

The effect of supplemental dietary arginine on dynamic changes in peripheral blood Th/ Ts ratio and survival rate were studied in burned rats (30% TBSA III degree). The results are as follows: 1. Th/Ts ratio dropped on the 3rd day and showed a trough value 10 days postburn. 2. Arginine could prevent the falling of Th/Ts ratio, which was distinct since 5 days after burn. 3. Survival rate 14 days postburn was raised in arginine rats. This study suggests that dietary arginine may be beneficial after severe burn.

[The effect of endurance training and exhaustive exercise on metallothionein in rats]

To understand physiological role of metallothionein (MT) during exercise, MT levels in liver, brain, heart, lung, blood vessel, skeletal muscle and serum were observed in rats. The results showed that the levels of MT were decreased by 13-34% in lung, liver, heart and skeletal muscle of rats trained by swimming for 10 weeks and were increased by 21%-75% in skeletal muscle, heart, brain, lung and liver of rats after exhaustive swimming respectively, compared with normal control rats. (P < 0.05 and P < 0.01). But the levels of MT in blood vessel and serum were not changed in two groups of rats by swimming for 10 weeks and acute exhaustive swimming (P > 0.05). It is suggested that the different changes of MT levels under physical training and acute exhaustive exercise may be of importance in protection against oxygen free radicals.

Study on enzyme electrode biosensor of choline

Choline oxidase was immobilized at a hydrogen peroxide electrode and the enzyme electrode was used for the amperometric determination of choline. The linear range is 0-200 mg/L with a response time of 40 seconds and a 25-microliter sample injection. The relative standard deviation (RSD) is less than 1.5% in 20 assays. The enzyme membrane can be used continuously at 25 degrees C for 60 days. The recovery rate of this method is 100.3-102.3%.

Myocardial imaging with a new transpulmonary lipid-fluorocarbon echo contrast agent: experimental studies in pigs

The development of echo contrast agents that can provide reliable opacification of the myocardium after intravenous injection is an important advancement for the clinical application of contrast echocardiography. In this study, the hemodynamic effects and echocardiographic characteristics of a new lipid-fluorocarbon echo contrast agent, Aerosomes MRX 115 (ImaRx Pharmaceutical Corp., Tucson, Ariz.) were studied in six anesthetized ventilated pigs. Intravenous injection of this new agent in doses ranging from 0.0005 to 0.01 ml/kg produced significant measurable and visible myocardial opacification without any effect on heart rate, systemic pressure, partial pressure of oxygen, or left ventricular systolic function. The two largest doses (0.005 and 0.01 ml/kg), however, resulted in mild reversible increases in mean pulmonary artery pressure of 12 and 16 mm Hg, respectively. In four animals, epicardial images were obtained before and during coronary artery occlusion. Intravenous contrast injection during coronary occlusion permitted delineation of the hypoperfused myocardial segment. This capability may further expand the utility of contrast echocardiography.

Quantification of mitral flow by Doppler color flow mapping

This study was performed to develop and validate Doppler color flow methods for quantifying forward transmitral flow rates and volumes with isovelocity aliasing contours. We undertook computer modeling of flows and studied an animal model with strictly controlled mitral flows. Finite element analysis was first used to establish the isovelocity surface contours reconstructed from the magnitudes and directions of the velocity vectors proximal to the normal mitral orifice. We modeled finite element-simulated Doppler color flow isovelocity surfaces and computed non-angle-dependent simulated isovelocities to compare them. Then 24 pharmacologically induced hemodynamic states in six sheep in which mitral regurgitation had been previously created surgically were studied. Three methods were used for peak flow (PF) computation: (1) the classic hemispheric methods: PF = 2 pi r2.aliasing velocity; (2) a modified hemispheric method: PF = 2 pi r2.aliasing velocity Vo/Vo-aliasing velocity; and (3) a new segment of sphere method: PF = pi p2.aliasing velocity, where p is the chord from the zenith of the first aliasing contour to the circumference at its base. Mean volume flow was also calculated in combination with phasic flow information from continuous-wave Doppler echocardiography: mean volume flow = PF.VTI/Vmax.heart rate, where VTI and Vmax are the velocity-time integral and maximal velocity of mitral inflow by continuous-wave Doppler echocardiography. Compared with the flow rates obtained by electromagnetic flowmeters, different correlations and agreements were achieved for these methods. Correlation (r = 0.86) and agreement were best for the segment of sphere method for computation of forward mean volume flows in our model. Color flow Doppler quantitation with a segment of sphere or modified hemispheric method appears applicable for quantification of forward transmitral valve flow rates and volumes with reasonable accuracy.

[Effects of hypertonic sodium lactate dextran resuscitation in severely burned dogs]

12 dogs with 35% TBSA third degree burns received HLD resuscitation (HLD group, n = 6) or LR resuscitation (LR group, n = 6). Fluid resuscitation started one hour postburn. The amount of fluid infused with HLD resuscitation was calculated by that after giving HLD 19.6 ml/kg in 3 hours and 6 ml/kg/% TBSA lactate Ringer's solution followed. The amount of fluid infused with LR resuscitation was calculated by 8 ml/kg/% TBSA lactate Ringer's solution. Infusion of lactated Ringer's solution in both groups was adjusted by maintaining urinary output 0.5-1 ml/kg/h. The volume of fluid infused in HLD group (5.05 +/- 1.11 ml/kg/% TBSA) was much less than that of LR group (10.03 +/- 1.30 ml/kg/%TBSA) (P < 0.01). There was no significant difference in urinary output, serum Na+ and albumin, and plasmacrystalloid osmolarity between two groups. Plasma level of MDA decreased after resuscitation with HLD, which (0.81 +/- 0.20 mmol/g Hb) was much lower than that (1.39 +/- 0.44 mmol/g Hb) of LR group 4 hours postburn (P < 0.05). Plasma SOD activity (7.22 +/- 0.68 u/g Hb) of HLD group were much higher than that of LR group (4.86 +/- 0.53 u/g Hb) 4 hours postburn (P < 0.05). HLD resuscitation could significant reduce the amount of fluid infused comparing with lactate Ringer's solution. HLD resuscitation could attenuate postburn damage to tissue induced by lipid peroxide by elevating plasma SOD activity.

Three-dimensional reconstruction of color Doppler flow convergence regions and regurgitant jets: an in vitro quantitative study

OBJECTIVES

This study sought to investigate the applicability of a current implementation of a three-dimensional echocardiographic reconstruction method for color Doppler flow convergence and regurgitant jet imaging.

BACKGROUND

Evaluation of regurgitant flow events, such as flow convergences or regurgitant jets, using two-dimensional imaging ultrasound color flow Doppler systems may not be robust enough to characterize these spatially complex events.

METHODS

We studied two in vitro models using steady flow to optimize results. In the first constant-flow model, two different orifices were each mounted to produce flow convergences and free jets--a circular orifice and a rectangular orifice with orifice area of 0.24 cm(2). In another flow model, steady flows through a circular orifice were directed toward a curved surrounding wall to produce wall adherent jets. Video composite data of color Doppler flow images from both free jet and wall jet models were reconstructed and analyzed after computer-controlled 180 degrees rotational acquisition using a TomTec computer.

RESULTS

For the free jet model there was an excellent relation between actual flow rates and three-dimensional regurgitant jet volumes for both circular and rectangular orifices (r = 0.99 and r = 0.98, respectively). However, the rectangular orifice produced larger jet volumes than the circular orifice, even at the same flow rates (p < 0.0001). Calculated flow rates by the hemispheric model using one axial measurement of the flow convergence isovelocity surface from two-dimensional color flow images underestimated actual flow rate by 35% for the circular orifice and by 44% for the rectangular orifice, whereas a hemielliptic method implemented using three axial measurements of the flow convergence zone derived using three-dimensional reconstruction correlated well with and underestimated actual flow rate to a lesser degree (22% for the circular orifice, 32% for the rectangular orifice). In the wall jet model, the jets were flattened against and spread along the wall and had reduced regurgitant jet volumes compared with free jets (p < 0.01).

CONCLUSIONS

Three-dimensional reconstruction of flow imaged by color Doppler may add quantitative spatial information to aid computation methods that have been used for evaluating valvular regurgitation, especially where they related to complex geometric flow events.

Intraoperative transesophageal echocardiography using high-resolution biplane 7.5 MHz probes with continuous-wave Doppler capability in infants and children with tetralogy of Fallot

This study reports the role of biplane transesophageal echocardiography in monitoring surgical repairs of tetralogy of Fallot. In our patients, 3 repairs were revised based on transesophageal echocardiography and continuous-wave Doppler results, and intraoperative management was altered in 2 others.

[Effects of resuscitation with hypertonic sodium lactate dextran 70 on cardiac function in severely burned dogs]

This comparative study was performed to evaluate the effects of resuscitation of burn shock with hypertonic sodium lactate dextran 70(HLD solution: Na+250 mmol/L and 6% dextran 70) and lactate Ringer' solution on cardiac function, lipid peroxide and SOD activity of heart tissue. Dogs with 35% TBSA third degree burns received, one hour postburn, either HLD resuscitation (HLD group, n = 6) in the amount of 19.6 ml.kg-1/g hours, followed by LR 6 ml.kg-1/% TBSA, or LR resuscitation (LR group, n = 6) in the amount of 8 ml.kg-1/% TBSA LR solution. The results of this experiment showed that cardiac index (CI) of HLD group was much higher than that of LR group at 4, 8, 12, 24 hours postburn. The dp/dt max and-dp/dt max of HLD group were much higher than that of LR group at 12.24 hours postburn. Level of MDA in heart tissue of HLD group (1.74 +/- 0.28 10 mol/g heart tissue) was much lower than of LR group (3.23 +/- 0.56 10 mol/g heart tissue) at 24 hours postburn (P < 0.01). Meanwhile, SOD activity in heart tissue of HLD group (157.49 +/- 32.23 u/mg heart tissue) was much higher than that of LR group (46.88 +/- 16.28 u/mg heart tissue) (P < 0.01). These results suggested that HLD resuscitation might be beneficial in improving postburn cardiac function and attenuating postburn oxidant-induced lipid peroxidation in heart tissue not only by its "oxygen scavenger" effect, but also by its elevation of SOD activity of heart tissue.