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Subcellular distribution of phenanthrene as a representative of polycyclic aromatic hydrocarbons (PAHs) in roots of five plants was investigated using a greenhouse hydroponic experiment. Results showed that, with the increase of the equilibrium concentrations of phenanthrene in solution from 0.056 to 0.39 mg x L(-1), the respective concentrations of phenanthrene in root, root cell organelle and cell wall increased from 26.85, 20.01 and 36.19 mg x kg(-1) to 56.91, 49.54 and 59.77 mg x kg(-1), and their concentration factors decreased from 357.14, 479.49, and 649.25 L x kg(-1) to 145.92, 127.04, and 153.26 L x kg(-1), respectively. The concentrations of phenanthrene in ryegrass root tissues followed the order of cell organelle > root > cell wall. In addition, concentrations of phenanthrene in cell organelle were generally 21%-163% higher than those in cell wall. As to the roots of five different tested plants growing in solution with initial phennathrene concentration of 1 mg x L(-1) after 144 h cultivation, the concentrations of phenanthrene were 48.64-145.2 mg x kg(-1) in root cell organelle, which were observed to be higher than those (15.86-74.49 mg x kg(-1)) in root cell wall. The subcellular distribution (%) of phenanthrene was in the following order: cell organelle > cell wall > cell soluble fraction. Based on the detected amounts of phenanthrene in subcellular fractions of plant root tissues, about 46%-53% and 31%-40% of phenanthrene were observed in root cell organelle and cell wall.

Carbohydrates are the main energy materials for plant metabolic activities. Enough carbohydrates stored in roots are necessary for plant re-growth, its tolerance against environmental stress, and the maintenance of grassland ecosystem stability. This paper summarized the influences of grazing, nitrogen fertilization, salt stress, drought, low temperature, and low oxygen stress on the carbohydrates in grassland plants, and introduced the advanced methods of measuring root carbohydrates. It was suggested that the research emphasis in the future should be paid on the relationships between root soluble sugar components and root physio-ecological functions.

Background: Experimental studies and preliminary clinical studies have suggested that growth hormone (GH) treatment may improve cardiovascular parameters in chronic heart failure (CHF). Recombinant human GH (rhGH) has been delivered by a recombinant protein, by plasmid DNA, and by genetically engineered cells with different pharmacokinetic and physiological properties. The present study aimed to examine a new method for delivery of rhGH using genetically modified bioartificial muscles (BAMs), and investigate whether the rhGH delivered by this technique improves left ventricular (LV) function in rats with CHF., Methods: Primary skeletal myoblasts were isolated from several Sprague-Dawley (SD) rats, cultured, purified, and retrovirally transduced to synthesize and secrete human rhGH, and tissue-engineered into implantable BAMs. Ligation of the left coronary artery or sham operation was performed. The rats that underwent ligation were randomly assigned to 2 groups: CHF control group (n = 6) and CHF treatment group (n = 6). The CHF control group received non-rhGH-secreting BAM (GFP-BAMs) transplantation, and the CHF treatment group received rhGH-secreting BAM (GH-BAMs) transplantation. Another group of rats served as the sham operation group, which was also randomly assigned to 2 subgroups: sham control group (n = 6) and sham treatment group (n = 6). The sham control group underwent GFP-BAM transplantation, and the sham treatment group underwent GH-BAM transplantation. GH-BAMs and GFP-BAMs were implanted subcutaneously into syngeneic rats with ligation of the left coronary artery or sham operation was performed. Eight weeks after the treatment, echocardiography was performed. hGH, insulin-like growth factor-1 (IGF-1) and TNF-alpha levels in rat serum were measured by radioimmunoassay and ELISA, and then the rats were killed and ventricular samples were subjected to immunohistochemistry., Results: Primary rat myoblasts were retrovirally transduced to secrete rhGH and tissue-engineered into implantable BAMs containing parallel arrays of postmitotic myofibers. In vitro, they secreted 1 to 2 microg of bioactive rhGH per day. When implanted into syngeneic rat, GH-BAMs secreted and delivered rhGH. Eight weeks after therapy, LV ejection fraction (EF) and fractional shortening (FS) were significantly higher in CHF rats treated with GH-BAMs than in those treated with GFP-BAMs ((65.0 +/- 6.5)% vs (48.1 +/- 6.8)%, P < 0.05), ((41.3 +/- 7.4)% vs (26.5 +/- 7.1)%, P < 0.05). LV end-diastolic dimension (LVEDD) was significantly lower in CHF rats treated with GH-BAM than in CHF rats treated with GFP-BAM (P < 0.05). The levels of serum GH and IGF-1 were increased significantly in both CHF and sham rats treated with GH-BAM. The level of serum TNF-alpha decreased more significantly in the CHF treatment group than in the CHF control group., Conclusions: rhGH significantly improves LV function and prevents cardiac remodeling in rats with CHF. Genetically modified tissue-engineered bioartificial muscle provides a method delivering recombinant protein for the treatment of heart failure.

Based on the near-infrared spectra (NIRS) of the measured samples as the discriminant variables of their genotypes, the genotype discriminant model of SNP has been established by using back-propagation artificial neural network (BP-ANN). Taking a SNP (857G>A) of N-acetyltransferase 2 (NAT2) as an example, DNA fragments containing the SNP site were amplified by the PCR method based on a pair of primers to obtain the three-genotype (GG, AA, and GA) modeling samples. The NIRS-s of the amplified samples were directly measured in transmission by using quartz cell. Based on the sample spectra measured, the two BP-ANN-s were combined to obtain the stronger ability of the three-genotype classification. One of them was established to compress the measured NIRS variables by using the resilient back-propagation algorithm, and another network established by Levenberg-Marquardt algorithm according to the compressed NIRS-s was used as the discriminant model of the three-genotype classification. For the established model, the root mean square error for the training and the prediction sample sets were 0.0135 and 0.0132, respectively. Certainly, this model could rightly predict the three genotypes (i.e. the accuracy of prediction samples was up to 100%) and had a good robust for the prediction of unknown samples. Since the three genotypes of SNP could be directly determined by using the NIRS-s without any preprocessing for the analyzed samples after PCR, this method is simple, rapid and low-cost.

The paper has established an approach of typing short tandem repeats (STRs) based on the near-infrared spectroscopy (NIRS)-chemical pattern recognition. Taking the three genotypes 9-9, 9-11 and 11-11 of D16S539 locus as example, which have a middle degree of difference, DNA fragments containing the polymorphism sites were amplified by a pair of primers to obtain three genotypes samples; these samples were tested by the NIRS directly; using their spectra as recognition variables, the chemical pattern recognition models of the three genotypes were respectively established by using the principal discriminant variate (PDV) and support vector machine (SVM). The two models have a good fitting ability and strong prediction (i.e. the predicting accuracy was 100%). They are robust for these strong collinear spectra and the small number of the calibration samples. Without any preprocessing for the analyzed samples after PCR, the three genotypes of D16S539 locus could be indirectly determined by using the NIRS-s of the samples with the help of the models. This method is simple, rapid and low cost.

A series of mixed rare earth complexes Eu(1-x)Tb(x) (BTC) x nH2O(H3BTC=1,3,5-H3BTC, x = 0.1, 0.3, 0.5, 0.7, 0.9, 1.0) were synthesized by the reaction of trivalent rare earth chlorides with trimesic acid. The contents of rare earth were mearsured by using EDTA titration method, the element analyses of C and H were performed by Vario EL elemental analyzer. Their infrared spectra were recorded by FTIR-8900 infrared spectrophotometer with KBr pellet, and the fluorescence spectra were recorded by using a Hitachi F-4500 fluorescence spectrophotometer at room temperature. These results show that these complexes Eu(1-x) Tb(x) (BTC) x nH2O can emit intense fluorescence from europium ion, the intensity of the fluorescence of the series complexes is greater in (5)D0-->7F(1,2), and both the positions ((5)D0-->7F(1,2)) show splitting emission peaks, but the peak positions of their emission spectra basically remain unchanged. These may be caused by the different coordinating pattern of the carboxylate groups. Additionally, the fluorescence intensity of europium ions was sensitized by terbium ions and that of terbium ions was quenched by europium ions. in these complexes. It was attributed to efficient energy transfer from the strongly absorbing ligand to the rather poorly absorbing lanthanide ion. and from Tb3+ to Eu3+. Moreover, the fluorescence emission of terbium ions increased markedly in these complexes.

This paper studied the enhanced fixation of phenanthrene in clay loam soil, sandy silt soil, and silt loam soil under effects of exotic organic materials (EOMs) commercial organic fertilizer and peat. The results showed that after the addition of EOMs, the adsorption isotherms of phenanthrene in test soils were still linear, and distribution was the predominant mechanism for phenanthrene adsorption by soil. The adsorption of phenanthrene was significantly enhanced by the addition of EOMs, and the enhancement of distribution constant (Kd) was positively correlated with the content of soil organic carbon (foc), indicating that the higher the soil foc, the more significant the promotion effect of EOMs addition on phenanthrene adsorption. On the contrary, the desorption of phenanthrene was obviously inhibited by the addition of EOMs. After 64 days of EOMs addition, the extractable amount of phenanthrene was decreased significantly, compared with the control. Since the organic matter content of peat was higher than that of commercial organic fertilizer, the decrease of extractable phenanthrene in soils added with peat was more significant. In addition, the higher the soil foc, the stronger inhibition effect of EOMs on extractability of phenanthrene. On the whole, exotic EOMs could promote the adsorption, while inhibit the desorption and reduce the extractability of phenanthrene in soils.

Background: Cell transplantation for myocardial repair is limited by early cell death. Gene therapy with human growth hormone (hGH) has been shown to promote angiogenesis and attenuate apoptosis in the experimental animal. This study was conducted to explore the effects of myoblast-based hGH gene therapy on heart function restoration and angiogenesis after myocardial infarction, and to compare the differences between myoblast-based hGH gene therapy and myoblast therapy., Methods: Myoblasts were isolated from several SD rats, cultured, purified, and transfected with plasmid pLghGHSN and pLgGFPSN. Radioimmunoassay (RIA) was used to detect the expression of hGH in these myoblasts. SD rats underwent the ligation of the left anterior descending coronary artery so as to establish a heart ischemia model. Thirty surviving rats that underwent ligation were randomly divided into 3 equal groups 2 weeks after left coronary artery occlusion: pLghGHSN group received myoblast infected with hGH gene transplantation; pLgGFPSN group received myoblast infected with GFP gene transplantation; control group: received cultured medium only. Four weeks after the injection the surviving rat underwent evaluation of cardiac function by echocardiography. The rats were killed and ventricular samples were undergone immunohistochemistry with hematoxylin-eosin and factor VIII. Cryosection was analyzed by fluorescence microscopy to examine the expression of green fluorescent protein. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to examine the mRNA expression of vascular endothelial growth factor (VEGF), bax and Bcl-2. hGH expression in myocardium was examined by Western blot., Results: Myoblast can be successfully isolated, cultured and transfected. The expression of hGH in transfected myoblast was demonstrated with RIA. Four weeks after therapy, the cardiac function was improved significantly in pLghGHSN group and pLgGFPSN group. Fractional shortening (FS) and ejection fraction (EF) in pLghGHSN group were elevated significantly compared with pLgGFPSN group and control group after therapy (FS: 36.9+/-5.3 vs 29.5+/-3.5, 21.8+/-2.9; EF: 56.9+/-4.3 vs 47.1+/-3.6, 38.4+/-4.8, P<0.05). Left ventricular end-diastolic dimension (LVEDD) and heart infracted size in pLghGHSN group were decreased significantly compared with pLgGFPSN group and control group after therapy (LVEDD: 5.9+/-0.3 vs 6.8+/-0.2, 8.6+/-0.3; heart infracted size: (34.5+/-4.2)% vs (40.0+/-3.9)%, (46.1+/-3.8)%, P<0.05); Green fluorescence was detected in cryosection of pLgGFPSN group. The capillary density of the pLgGFPSN group was significantly greater than those of the pLghGHSN group and control group (P<0.05). The mRNA expression of VEGF and Bcl-2/bax in pLghGHSN group was higher than in pLgGFPSN group or control group (P<0.05). The expression of hGH gene in myocardium tissue can be detected by Western blot assay in pLghGHSN group., Conclusions: Transplantation of heart cells transfected with hGH induced greater angiogenesis and effect of antiapoptosis than transplantation of cells transfected with GFP. Combined GH gene transfer and cell transplantation provided an effective strategy for improving postinfarction ventricular function.

Objective: To search novel genes or pathways involved in the recovery process after restraint stress in rats., Methods: We compared the hypothalamus transcriptional profiles of two different recovery patterns (fast recovery vs slow recovery) from restraint stress in rats using oligonucleotide microarray, the recovery pattern was determined by the decrement of plasma adrenocorticotropic-hormone (ACTH) and corticosterone levels during one hour recovery period after stress. A real-time quantitative RT-PCR was applied to validate the differential expressed genes., Results: Analysis of the microarray data showed that most of genes were not differentially expressed between fast recovery group and slow recovery group. Among the differentially expressed genes we found that talin, together with serine/threonine protein phosphatase PP1-beta catalytic subunit (PP-1B) and integrin alpha-6 precursor (VLA-6) genes, were at least 1.5 fold up-regulated in the fast recovery group, while junctional adhesion molecule 1 (F11r) was 1.5 fold down-regulated in the fast recovery group., Conclusion: The results implied that integrin signaling pathway may be involved in the recovery from restraint stress in rats. The present study provided a global overview of hypothalamus transcriptional profiles during the process of recovery from the restraint stress in rats. The integrin signaling pathway seems to be involved in the recovery process, which deserves further study to clarify the integrin-mediated recovery mechanism after restraint stress.

This paper studied the effects of exotic and native dissolved organic matter (DOM) on the phenanthrene adsorption by three soils differed in soil organic carbon content (foc). The exotic DOM came from decayed rice straw, while the native DOM was extracted from the test soils. In all cases, the adsorption of phenanthrene by treated soils could be well described with linear-type model, and there was a positive correlation between adsorption coefficient (Kd) and foc Compared with the control, the Kd value of test soils after native DOM removed was increased by 7. 08% -21. 4% , and the increment (deltaKd) was positively correlated with fo,, indicating that the presence of soil native DOM impeded the phenanthrene adsorption by soil. The effects of exotic DOM on phenanthrene adsorption had a close relation with its added concentration in soil-water system. Within the range of 0-106 mg DOC x L(-1) , the K, value increased first, and then decreased with the increase of added exotic DOM concentration. Lower concentrations of added exotic DOM promoted the phenanthrene adsorption by soil, while higher concentrations ( I> or =52 mg DOC x L(-1)) of it obviously impeded this adsorption. These effects of exotic and native DOM on soil phenanthrene adsorption were considered to be related to the association of phenanthrene with DOM in solution, and the ' cumulative adsorption effect' between soil solid and aqueous phases.

Genetic variations in the NADPH/MPO system in chronic kidney disease (CKD) patients might lead to altered activity of these enzymes, and thus to altered risk for oxidative stress (OS) and cardiovascular disease (CVD). We evaluated the impact of 242C/T CYBA and -463G/A MPO polymorphisms on OS and CVD mortality in stage 5 CKD patients starting dialysis. Two hundred and fifty-seven patients were genotyped using Pyrosequencing. Plasmalogen [dimethylacetal (DMA) 16/C16:0] was used as OS marker. CVD was assessed from patient history and clinical symptoms. Prevalence of CVD was higher (35%) in GG patients (MPO) compared to AG (26%) and AA (0%) patients (p < 0.01). Patients with CC genotype (CYBA) had lower levels of DMA 16/C16:0 (ratio 0.071 +/- 0.003) compared to TT patients (0.089 +/- 0.006; p < 0.05). These patients also had increased CVD mortality compared to CT and TT patients (chi(2) 2.19; p < 0.05). We conclude that genetic variations in the NADPH/MPO system are associated with OS, presence of CVD and CVD-related mortality in CKD patients., (Copyright (c) 2007 S. Karger AG, Basel.)

The aim of the present study is to probe candidate genes which were involved in the electroacupuncture (EA) analgesia and to understand the molecular basis of the individual difference of EA analgesia in rats. We compared hypothalamus transcriptional profiles of responders with those of non-responders after 1 Hz EA treatment at ST36 acupoint for 1 hour by using oligonucleotide microarray. Responders and non-responders were determined by tail flick latency (TFL). A real-time quantitative RT-PCR was applied to validate the differential expressed genes. Our study provided a global hypothalamus transcriptional profile of EA analgesia in rats. We found that 63 and 3 genes were up- and down-regulated in the responder group, respectively. Half of the differentially expressed genes were classified into 9 functional groups which were ion transport, sensory perception, synaptogenesis and synaptic transmission, signal transduction, inflammatory response, apoptosis, transcription, protein amino acid phosphorylation and G-protein signaling. Glutamatergic receptors, ghrelin precursor, melanocortin 4 receptor (MC4-R) and neuroligin 1 were found to be up-regulated in the responder group which may become new targets for nociceptive study and deserve further investigation for developing new acupuncture therapy and intervention of pain modulation.

Background: This study transferred a recombinant gene encoding human insulin like growth factor-1 (hIGF-1) into modified primary skeletal myoblasts with a retroviral vector (pLgXSN) and determined whether the hIGF-1 promoted growth of skeletal muscle in rat., Methods: hIGF-1cDNA was amplified in vitro from normal human liver cells by using RT-PCR and cloned into plasmid vector pLgXSN. The recombinant vector pLghIGF-1SN and control vector pLgGFPSN were transfected into packaging cell PT67 and G418 was used to select positive colony. Myoblasts were infected with a high titre viral supernatant and transduction efficiency was evaluated as GFP expression. The expression of hIGF-1 mRNA in myoblasts was investigated by immunocytochemistry and RT-PCR. MTT assays detected the growth of myoblasts in vitro. Myoblasts transduced with pLghIGF-1SN were injected into hind limb muscles of 10 - 12 week male SD rats. Formed tissues were harvested 4 weeks later. Myocyte diameter, mean weight of hind limb and body were measured to evaluate the skeletal muscle growth., Results: Recombinant retroviral plasmid vector pLghIGF-1SN was constructed successfully. The titre of the packaged recombinant retrovirus was 1 x 10(6) cfu/ml. The transfection rate of PT67 cells reached 100% after G418 screening. hIGF-1 expression was positive in myoblast-IGF-1. The proliferation rate of myoblast-IGF-1 in vitro was higher than GFP-myoblast or myoblast (P < 0.05). The mean weights of hind limb and body of rats injected myoblast-IGF-1 were higher than those of the rats injected with myoblast-GFP or myoblast (P < 0.05). Myocyte diameter had a significant increase in IGF-1 group compared to GFP group and myoblast group (P < 0.05)., Conclusions: The transfection of the human IGF-1 gene mediated by a retroviral vector can promote the growth of skeletal muscle in rats. Genetically modified primary skeletal myoblasts provide a possibly effective approach to treat some skeletal muscle diseases.

Background: The management of severe hepatic trauma frequently involves exposing the liver to varying periods of warm ischemia. The ischemic tolerance of the liver, in the setting of hemorrhagic shock (HS) and trauma, is presently unknown. We tested the hypothesis that warm ischemic tolerance of the porcine liver will be decreased following resuscitation from HS., Materials and Methods: Twenty-three Yorkshire pigs were divided into three groups: 1) hepatic ischemia alone (HI, n = 9); 2) hemorrhagic shock alone (HS, n = 3); and 3) hemorrhagic shock plus hepatic ischemia combined (HSHI, n = 11). Following reperfusion, a liver biopsy was obtained and serial blood chemistries were sampled., Results: Post-operative day 7 mortality was increased in the HSHI group (7/11) compared to the HI (0/9) group, P = 0.038. Notably, deaths did not result from acute liver failure, but rather from intra-operative hemodynamic collapse shortly following hepatic reperfusion. In addition, the HSHI group experienced significantly elevated lactic acid, serum creatinine and liver enzyme levels. Analysis of the liver biopsy samples is consistent with a more severe liver injury in the HSHI group., Conclusions: The warm ischemic tolerance of the liver following resuscitation from HS is significantly decreased in this porcine model compared to HS or HI alone. Mortality was associated with acute intra-operative hemodynamic collapse occurring shortly after hepatic reperfusion.

Phytoremediation of soil contaminated with phenanthrene and pyrene was investigated using twelve plant species. Plant uptake and accumulation of these chemicals were evaluated. At the end of the experiment(45 d), the remaining respective concentrations of soil phenanthrene and pyrene in spiked vegetated soils, with initial phenanthrene of 133.3 mg/kg and pyrene of 171.5 mg/kg, were 8.71-16.4 and 44.9--65.0 mg/kg, generally 4.7%--49.4% and 7.1%--35.9% lower than their concentrations in the non-vegetated soils. The loss of phenanthrene and pyrene in vegetated spiked soils were 88.2%--93.0% and 62.3%--73.8% of the added amounts of these contaminants, respectively. Although plant uptake and accumulation of these compounds were evident, and root concentrations and RCFs (root concentration factors; defined as the ratio of PAH concentrations in roots and in the soils on a dry weight basis) of these compounds significantly positively correlated to root lipid contents, plant uptake and accumulation only accounted for less than 0.01% and 0.23% of the enhanced loss of these chemicals in vegetated versus non-vegetated soils. In contrast, plant-promoted microbial biodegradation was the dominant mechanism of the phytoremediation for soil phenanthrene and pyrene contamination. Results from this study suggested a feasibility of the establishment of phytoremediation for soil PAH contamination.

The dissolved organic matter (DOM), water soluble organic matter derived from sewage sludge was separated into hydrophobic fraction (Ho) and hydrophilic fraction (Hi). The sorption of DOM and its fractions on soils and the effects of DOM sorption on a nonionic pesticide (atrazine(2-chloro-4-ethylamino-6-isopropylamino-1,3,5-trazine)) distribution between soil and water were investigated using a batch equilibrium technique. The total DOM sorption on soils described by the Langmuir equation reached saturation as the DOM concentration increased. The sorption of Ho fit the Freundlich model. In contrast, a negative retention evidently occurred as adding Hi at higher level in tested soils. The sorption of Ho dominated the total DOM sorption and the release of soil organic matter (SOM). Effects of DOM on the atrazine sorption by soils were DOM-concentration dependent and dominated by the interaction of atrazine, DOM, and soil solids. Generally, the presence of DOM with lower concentration promoted atrazine sorption on soils, namely the apparent partitioning constant (Kd) for atrazine sorption in the presence of DOM was larger than the distribution constant (Kd) without DOM; whereas the presence of DOM with higher concentration inhibited atrazine sorption (i.e., Kd < Kd). The overall effects of DOM on atrazine sorption in soils might be related to the DOM sorption and the release of soil intrinsic organic matter into aqueous solution. The sorption of Ho on soils promoted the atrazine sorption on soil, while the release of SOM by Hi and the competitive sorption between Hi and atrazine on soil surface led to a decrease of atrazine sorption. Information provided in this work may contribute to a better understanding of the DOM sorption and its impacts on the contaminant soil-water distribution.

Objective: To obtain the genetic polymorphism data of two STR loci D2S1399 and D5S2500 in Eastern Chinese Han population., Methods: Blood samples or buccal swabs of unrelated Han individuals living in eastern China were analyzed using PCR-nature polyacrylamide gel electrophoresis-sliver staining method., Results: 11 alleles of D2S1399 and 9 alleles of D5S2500 were observed in the samples respectively, the observed heterozygosity (Ho) values, the discrimination power (DP) values and the power of exclusion (PE) values of D2S1399 and D5S2500 is 0.745 and 0.807, 0.958 and 0.917, 0.554 and 0.643, respectively., Conclusion: The result showed that D2S1399 and D5S2500 were highly informative loci and suitable for forensic application.

Ten polycyclic aromatic hydrocarbons (PAHs) were simultaneously measured in 9 surface water samples of Qiantang River and Hangzhou Canal in Hangzhou, China, in December of 2002. It was observed that the sum of PAHs concentrations ranged from 1.104 to 9.663 microg x L(-1) in surface water, from 132.7 to 7343 microg x kg(-1) dry sediments, and from 59.71 to 219.5 microg x kg(-1) dry soils. The accumulative coefficients of PAHs in sediments and soils (K) and apparent partition coefficients normalized by solid organic carbon contents (K(OC)*) were calculated. In Hangzhou Canal, K and K(OC)* values in sediments increased with downstream, and ratio of K(OC)* on sediment to K(OC)* on soil were much larger than 1. Those indicated that Hangzhou Canal was heavily polluted by PAHs released from factory wastewater and PAHs in sediment were mainly sources of PAHs in surface water. In Qiantang River, K and K(OC)* values in sediments decreased with the downstream, and the ratio of K(OC)* on sediment to K(OC)* on soil near 1, and ratio fOC of sediment to fOC of soil approximate to 1, which showed that PAHs in Qiantang River were attributed to soil runoff.

Soil pollution has been attracting considerable public attentions over the last decades. Sorts of traditional physiochemical methods have been used to remove the organic pollutants from soils. However, the enormous costs and low efficiencies associated with these remediation technologies limit their availabilities. Phytoremediation is an emerging technology that uses plants to cleanup pollutants in soils. As overwhelmingly positive results have been shown, phytoremediation is a most economical and effective remediation technique for organic contaminated soils. In this paper phytoremediation and its models for organic contaminated soils are viewed. The mechanisms of phytoremediation mainly include the direct plant uptake of organic pollutants, degradation by plant-derived degradative enzymes, and stimulated biodegradation in plant rhizosphere. Phytoremediation efficiency is close related to physicochemical properties of organic pollutants, environmental characteristics, and plant types. It is no doubt that soil amendments such as surfactants improves the solubilities and availabilities of organic pollutants in soils. However, little information is available about effects of soil amendments on phytoremediation efficiencies. Phytoremediation models have been developed to simulate and predict the environmental behavior of organic pollutants, and progress of models is illustrated. In many ways phytoremediation is still in its initial stage, and recommendations for the future research on phytoremediation are presented.

In 1953, Watson and Crick set forth their hypothesis for the double-helical nature of DNA. The Watson-Crick model had an immediate effect on the emerging discipline of molecular biology. It was a remarkable feat and highly significant in the history of genetics and biology.

Background: We treated 20 cases of craniovertebral junction lesions via a transoral approach. Developmental abnormalities of the craniovertebral junction accounted for 15 cases; there were 3 cases of tumor, 1 case of osteomyelitis, and 1 case of rheumatoid arthritis., Methods: The transoral transpharyngeal approach was used in all cases. In 17 non-tumoral patients the anterior margin of the atlas and the odontoid process were resected. In one patient with a ventral clivus chordoma, both a transoral and a transnasal transsphenoidal approach was used for partial resection of the tumor mass. In two cases the median transpharyngeal approach was combined with a jaw-facial incision. In one case a metastatic adenocarcinoma, and in another a neurinoma of the accessory nerve straddling the posterior fossa and the pharyngeal region were removed., Results: After operation four cases developed craniovertebral joint instability and required posterior cervical fusion or external fixation with a halo brace. Follow-up ranged from 2 to 44 months. In most patients neurologic function slowly improved. One worsened, and one died of respiratory failure after operation. Two patients with malignant tumors died during the follow-up period., Conclusion: In patients with developmental malformations, transoral decompression will result in some neurologic improvement and arrest the progress of symptoms. Patients with tumors are likely to show a good neurologic outcome when transoral surgery is performed in the early stage of the condition.

Based on our 12 cases of lesions located at anterolateral area of brain stem which were successful operated upon via far-lateral approaches, the study and progress of the far-lateral approaches were reviewed. In our cases, there were 4 intramedullary lesions including 3 vascular malformations, and 1 glioma. The other 8 lesions were located at extramedullary anterolateral area of brain stem including 2 large acoustic neuromas, 2 meningiomas at clivus and 2 neurofibromas at anterolateral areas of the medulla oblongata and upper spinal cord, 1 teratoma at the anterolateral area of pone-medulla and 1 large aneurysm at the junction of vertebrobasilar artery. During the operations, 8 lesions were totally removed. 1 meningioma was subtotally removed. 2 (1 vascular malformation and 1 glioma) were subtotally removed too, the aneurysm was only given a decompression of increased intracranial pressure, because the patient's interrupted respiration during the operation. There were nooperative mortality and morbidity and good results were obtained in this group. The details of our modified far-lateral approach was also described in this paper.

18 cases of pathological cavernoma of the central nervous system were reported. The took 11.25 per cent of verified vascular malformations in our department in the same period. 15 cases located intracranially, and 3 cases were within the vertebral canal. Repeated small amount hemorrhages in the lesions were the major cause of the clinical symptoms of these patients. MRI was the most reliable method for making a correct diagnosis of cavernomas before operation. Cavernomas usually had clear border and surrounded with gliotic tissues, so that extirpation of tumor with microsurgical technique was the best choice.

In this study we applied the technique described in the previous paper (see pp. 103-106 of previous issue (1991); 13(2)) to rats with experimental saccular aneurysms. We found that the mean sizes and some growth ratios of experimental aneurysms were significantly larger in the intermittent blood pressure elevation groups than in the control groups. The increase of growth ratios was proportional to the number of transient blood pressure elevations. The morphological structure of these saccular aneurysms showed that the regenerative processes in the aneurysm wall had obviously been interfered with in animals with intermittent blood pressure elevation. The effective mechanism of this influential factor is discussed.

Haemodynamic factors in the formation and development of saccular aneurysms have been widely studied. Saccular aneurysms could appear and grow at the side of the increased blood flow. The effects of contralateral carotid ligation on the formation and growth of our experimental saccular aneurysms were studied. Measurement and pathological examination showed that the haemodynamic changes could facilitate the development of saccular aneurysms, but by itself could not bring about their formation.

Although the reason for development of saccular aneurysms in humans has still not been elucidated, the process might be observed and explained using a reproducible aneurysm model in vivo. In this paper, a sequential pathological study of the experimental saccular aneurysms was made. No additional influential factors were applied. At all stages of the development between the induction and 6 months, the histology of the aneurysm wall was similar to that of human aneurysms. The imbalance of the degeneration and regeneration processes during the development of these experimental aneurysms is discussed according to the pathological findings in different periods. Haemodynamic stress and different regenerative speeds in different arterial tissues must be responsible for the saccular aneurysm formation and growth.

Three methods were applied to estimate the carrier risk of the daughter of an obligate carrier of the Duchenne gene in a pedigree of Duchenne muscular dystrophy (DMD). According to Mendel's law of segregation, the daughter (III-3) of the obligate carrier (II-2) has a 50% chance of being a carrier. III-3 is also found to have a normal value in a carrier test, creatine phosphate kinase (CPK), and so the Bayesian analysis in risk estimation shows that the posterior probability that she is a carrier (25%). The restriction fragment length polymorphism (RFLP) linkage analysis indicates that the probability that III-3 is a carrier less than 5%. This result can be included in the Bayesian analysis to give an even lower risk of less than 2%. Our study demonstrates that the best result of carrier risk estimation can be obtained by a simultaneous application of Mendel's law, RFLP linkage analysis and the Bayesian analysis.

A new and reproducible saccular aneurysm model has been developed at the bifurcation of the common carotid artery in rats. The details of the experimental methods and results are described. It is strongly suggested that the internal elastic lamina is a critical layer in saccular aneurysm formation, because an experimental saccular aneurysm can be produced immediately by transluminally damaging the inside of the arterial wall at the bifurcation of the common carotid artery. This saccular aneurysm model has several advantages: (i) it can be induced quickly and the success rate approaches 100% in rats; (ii) this technique can produce satisfactory experimental saccular aneurysms for other aneurysm studies, and in the future it will also be possible to use this technique to produce experimental saccular aneurysms in cerebral arteries of large animals.

After 2 and 3 months we re-exposed 20 experimental saccular aneurysms. Under the operating microscope, we measured their sizes and compared them with the sizes immediately after induction. All aneurysms had grown significantly and none was thrombosed. Pathological examinations showed that the sac of the aneurysm was similar to that of the human saccular aneurysms. Based on the operating microscopy and pathological findings we postulate that abnormal histological structure and haemodynamic stress are the major causes of aneurysm enlargement. We also noted that there were some regenerative processes in these experimental aneurysm walls. The results prove that this model is reliable, because these aneurysms have the main characteristics of human saccular aneurysms, not only grossly but also microscopically.