[Removal of arsenic from dispersed drinking water by iron oxide-coated sand]

The iron oxide-coated sand(IOCS) was developed by treating normal river sand with molysite and investigated by batch, column tests and autoptic experiment to evaluate it's ability of eliminating arsenic from dispersed drinking water. The results showed that IOCS was relatively stable and can be seen iron oxide distributedly patched the surface of sand by scan electron microscope. IOCS needn't any activation pretreatment. It reached the maximum adsorption within 30-60 min. The removal percentage of arsenate was decreased but the one of arsenite had little change when the pH varied from 5 to 9. And the arsenic adsorption matched the Langmuir isotherm. In 5 circles of runs, it treated 408-426 (arsenite) beds and 390-412(arsenate) beds volume of water with 75 g(50 ml) IOCS respectively when the influent arsenic concentration was 1.0 mg.L-1. And the arsenic percentage recovery was above 94% when regenerating the IOCS by 0.2 mol.L-1 NaOH. The home simulation unit contained IOCS 3.0 kg produced 209 L and 198 L, 196 L and 185 L of water when the influent arsenate or arsenite concentration was 1.0 mg.L-1, and 200 L arsenic free water with the influent arsenic 0.202-1.733 mg.L-1 during the field experimental period. The water quality was not affected by the adsorbent. With low-cost and simple operation, the IOCS should be a promising novel medium for arsenic removal in dispersed drinking water.

[Factors affecting arsenic removal with copolymer coagulant and their mechanism]

The removal of arsenic from drinking water with copolymer coagulant was investigated. The effect of the component, additive substance of the coagulant and filtration were tested by employing a orthogonal analysis. The results showed that the arsenic removal with ferric sulfate was better than that with ferric-aluminum copolymer and polysilicon metal salt. Adding active carbon powder or kaoline could not enhance the efficacy of arsenic removal. However, the removal rate was improved by filtration after using coagulates, and sand filtration was feasible. The efficacy of arsenic removal could be affected by the column height filled with sand and the diameter of sand. After arsenic adsorption model fitted, the Lang-muire isotherm was matched. The main mechanism of arsenic removal by coagulation should be adsorption.

[Relation between BDNF and synaptic reorganization of hippocampal mossy fibers]

OBJECTIVE

To investigate the relation between brain-derived neurotrophic factor (BDNF) and synaptic reorganization of hippocampal fibers (MF).

METHODS

Antisense or sense oligomucleotides to BDNF and/or PBS buffer were injected into the cerebal ventricles of rats of epileptic model induced by kainic acid (KA) and control rats respectively. Immunohistochemical staining and Timm's silver sulfide staining were used to examine the effect of antisense oligonucleotides to BDNF upon the MF sprouting in the KA model and control rats.

RESULTS

Timm's staining showed that multiple aberrant Timm's granules were found in the inner molecular layer (IML) of the dentate gyrus of hippocampus of the KA model rats intracerebroventricularly injected with sense oligonucleotides to BDNF or PBS, less aberrant Timm's granules were found in the hippocampal IML of KA model rats intracerebroventricularly injected with antisense oligonucleotides to BDNF, and no aberrant Timm's granule was found in the hippocampal IML of non-KA model rats intracerebroventricular injected with antisense oligonucleotides to BDNF. Immunohistochemical staining showed multiple BDNF immunologically labeled neurons in the hilus and CA3 region of hippocampus of KA model rats intracerebroventricularly injected with sense oligonucleotides to BDNF and PBS, less in the KA model rats intracerebroventricularly injected with antisense oligonucleotides to BDNF, and only a few in the non-KA model rats. The A value in both Timm's and immunohistochemical sections of KA model rats was higher than that of non-KA model rats. The A value in both Timm's and immunohistochemical sections of KA model rats was significantly lower in the groups injected with antisense oligonucleotides to BDNF than in the group injected with sense oligonucleotides.

CONCLUSION

BDNF may play an important role in promoting the MF sprouting caused by repeated epileptic convulsion in the course of MF synaptic reorganization. The expression of BDNF protein can be upregulated by subcutaneous injection of KA and be decreased by intracerebroventricular injection of antisense oligonucleotides to BDNF.

[Study on the removal of arsenite from dispersed drinking water]

The feasible methods for oxidation and removal of arsenite[As(III)] from dispersed drinking water were based on the removal of arsenate[As(V)] by ferric sulfate. The results showed that the spotaneous oxidation of As(III) to As(V) was very slow and could not be enhanced by aerating for 24 h. The removal rate of As(III) could reach that of As(V) when pre-aerating water samples with ozone for 60 s, putting 7.5 ml/L hydrogen peroxide solution, adding 2.5 mg/L javelle water (sodium hypochlorite) or 15 mg/L bleaching powder(numerated by chlorine). The oxidation by using javelle water was rather stable when samples were varied in pH value, hardness, initial concentration of As(III) and As(III)/As(V) ratio. The effective oxidation could be reached with 1.25 mg/L javelle water when the initial concentration of As(III) was < or = 0.8 mg/L. Moreover, the field study also confirmed the oxidation effect of javelle water. It is suggested that javelle water is an effective, economic and technologic feasible oxidationagent for removing arsenite from dispersed drinking water.

Analysis of nonvolatile species in a complex matrix by headspace gas chromatography

This study developed a phase reaction conversion (PRC) headspace gas chromatographic (HS-GC) technique for the measurements of nonvolatile species in liquid or solid samples. The technique is demonstrated by the measurements of carbonate in aqueous carbonate solutions and in kraft pulp mill liquor samples. A very small amount of sulfuric acid (volume of 0.5 ml, concentration of 2 mol/l) is used to acidify a sample of less than 300 microl in volume and convert the dissolved carbonate into carbon dioxide (gas) in a sample vial (reactor) that is analyzed by thermal conductivity detection through a headspace sampler. The carbonate concentrations measured by PRC-HS-GC in seven kraft liquor samples agree very well with those measured using a coulometric and a titrametric method. Simultaneous analysis of multiple species was also conducted to demonstrate the versatility of the method. The present method is very simple, rapid, reliable, accurate, and fully automated. It can be applied to analyze other nonvolatile species in various industrial and environmental samples.

[The effect of rhIL-11 on hematopoiesis of rhesus monkeys irradiated with 60Co gamma-rays]

OBJECTIVE

To study the therapeutic effect of recombinant human interleukin-11 (rhIL-11) on acute radiation sickness in monkeys.

METHODS

rhIL-11 (30, 60, 120 micrograms.kg-1.d-1, s.c., on days 0-13 after TBI) or vehicle was administered to rhesus monkeys irradiated with 3.0 Gy 60Co gamma-rays.

RESULTS

The nadirs of platelet count were significantly improved after treatment with rhIL-11. The duration of platelet and leukocyte numbers below 50% of their baseline values was shortened. Erythrocyte recovery was also accelerated. Semi-solid bone marrow cell culture demonstrated that rhIL-11 could stimulate monkey's bone marrow cell to form more CFU-MK, CFU-Mix, CFU-E and BFU-E in vitro, especially at the dose of 60 micrograms.kg-1.d-1. Histopathological observation revealed that bone marrow of the untreated controls showed large area of bleeding whereas that of the rhIL-11 treated monkeys was in active proliferation.

CONCLUSION

rhIL-11 can accelerate hematopoietic recovery of monkeys received 3.0 Gy total body gamma-rays irradiation.

[Release character of phosphorus from the sediments of east Lake, Wuhan]

Effects of environmental factors on the release of phosphorus were studied at laboratory simulated test. The relationship between the different forms of phosphorus in sediments and the quantity of releasing phosphorus was studied at the same time. Results showed that the rates of phosphorus release from the sediment increased with rising the temperature of disturbing the overlying water. The content of phosphorus release from the sediment reached the lowest level when pH value was 7.4, high pH or low pH increased the rates of phosphorus release from the sediment. In anaerobic, the release rates of phosphorus was 30 times as much as in aerobic. Research also showed that different chemical forms of phosphorus in sediments were related to the quantity of phosphorus released from the sediments in varying degrees. The dissolved phosphorus and Fe binding phosphorus in sediments played the most important roles (r > 0.90, P < 0.01).

[Study on a downstream signal molecule of human CASK/LIN-2]

OBJECTIVE

To elucidate the function of human CASK/LIN-2, a novel member of membrane-associated guanylate kinase homologs family (MAGUK), by using the yeast two-hybrid system(LexA) to screen the protein interacting with the guanylate kinase-like domain(GK) of hCASK and identify possible protein that might involve downstream signal transduction of hCASK.

METHODS

PCR strategy was used to amplify GK domain cDNA fragment of hCASK. The DNA was subcloned into pLexA to construct bait vector pLexA-GK. The pLexA-GK was transformed into yeast host strain EGY48; through testing the bait protein and a repression assay, it was demonstrated that the bait protein did not have transcription activation for leu and lacZ reporter genes, however it could enter nucleus, bind LexA operator. Human fetus brain cDNA library plasmids were transformed into EGY48 containing pLexA-GK and p8op-lacZ, and screened on plates of Gal/Raf his- trp- ura- leu- and Gal/Raf his- trp- ura-X-gal. The clones with galactose dependent leu+ and lacZ+ were isolated; their library plasmids were rescued by means of transforming E.coli KC8. These library plasmids were transformed into the yeast again to re-screen. The remaining positive clones were analyzed by PCR and restriction endonuclease. Finally two kinds of target DNA fragments were obtained.

RESULTS

The specificity testing indicated that the two target proteins could specially bind GK domain of hCASK. After DNA sequencing and BLASTn analysis on NCBI, it was shown that the two target DNA fragments, 732 and 683 bp, had high sequence similarity with human inhibitors of differentiation 1(Id1) mRNA, with identities of 97%(630/645) and 98%(656/666), respectively.

CONCLUSION

GK domain of hCASK could specially interact with Id1 in yeast. Id1 might be a downstream signal molecule of hCASK, which might involve in regulation of cell differentiation.

Synthesis and characteristics of the human serum albumin-triazine chiral stationary phase

Human serum albumin (HSA) was successfully bonded to silica with s-triazine as activator. The coupling reaction by this method was rapid and effective. The triazine-activated silica is relatively stable and can be installed for at least 1 month without obvious loss of reactivity when stored below 30 degrees C, pH below 7. It was observed that the amount of bound HSA reached 120 mg/g silica calculated from the UV absorbance difference of the HSA solution. d, l-tryptophan was selected as the probe solute to characterize the properties of HSA bonded s-triazine chiral stationary phase, and separation factor of 9.4 was obtained for d,l-tryptophan. Furthermore, the amount of effective HSA on silica was measured by high-performance frontal analysis, and only 16.8 mg/g silica was responsible for the resolution of d,l-tryptophan. These results indicate that the amount of both the bound and effective HSA on silica with triazine as activator was much higher than those by the Schiff base coupling method. Different kinds of enantiomers were resolved successfully on the aminopropylsilica-bonded HSA s-triazine chiral stationary phase.

[Endoscopy-assisted neurosurgery for intracranial operation]

OBJECTIVE

To investigate the value of endoscope-assisted neurosurgery for intracranial operation.

METHODS

37 patients with intracranial lesions including tumors, aneurysms, cysts, hematomas, hydrocephalus and nerve-vessel compression syndrome were treated with this method. Their results were compared to those of microsurgery and macrosurgery. The items analyzed included exposure and protection of brain tissue and cranial nerves, views of operation field, length of procedure etc.

RESULTS

15 patients with tumors, showed a high rate of complete removal but less complications. The 6th nerves of CPA tumors operation were preserved. Six cases of nerve-vessel compression syndrome showed excellent therapeutic effects. In 8 cases of intraventricle lesions, using endoscope easily found tumor location and the cause of hydrocephalus. As to saccular diseases, endoscope was used to deal with the major location. In 4 cases of hematomas, less blot remained and the procedure shortened. Moreover the operation field was more clear and adequate on the expenses of no more complexity of the procedure.

CONCLUSIONS

Endoscope-assisted microsurgery is helpful in intracranial operation. It might become a standard neuro-operation in near future.

[Ultrastructure study on extraocular muscle of infiltrative exophthalmos]

OBJECTIVE

To investigate histopathologic and ultrastructural changes of extraocular muscles (EOMs) in infiltrative exophthalmos in order to collect some evidences of pathogenesis.

METHODS

Ten EOM samples in infiltrative exophthalmos were obtained after operation. Each of them was cut into two pieces. One of them was stained with HE and observed by light microscope. Another one was sectioned with ultrathin method and observed by transmission electron microscope.

RESULTS

Under the light microscope, the extraocular muscular cells had no significant abnormality at the early stage, while at the middle and late stage, sarcoplasm coagulation, granular degeneration, vacuolization and necrosis were found in the cells. Under the electron microscope, there were disturbance and disappearance of the Z line in part of muscular fibers in early cases; at the middle and late stage, various degrees of sarcoplasmic reticulum dilatation, myofilament lysis and destruction with formation of vacuoles, secondary lysosome and remnant bodies were seen. In severe cases, the muscular cells could be completely destroyed and phagocytosed by macrophages, fibrosis occurred and myofibroblasts were found in some cases.

CONCLUSIONS

The EOMs in infiltrative exophthalmos are destroyed in various degrees, and the muscular cells may be the target cells in Graves' ophthalmopathy.

Nonparaxial propagation of a cylindrical beam with Lanczos reduction

We discuss a numerical method based on Lanczos reduction of modeling nonparaxial propagation of a cylindrical symmetric beam. To illustrate the performance and demonstrate the significant difference between nonparaxial and paraxial beams, we consider Gaussian beam propagation in two different settings.

[The inhibitory effects of chloroquine and dexamethasone on the formation of pulmonary edema in the early stage of smoke inhalation injury in rats]

OBJECTIVE

To explore the inhibitory effects of chloroquine and dexamethasone on the formation of pulmonary edema in the early stage of smoke inhalation injury in rats.

METHODS

Wistar rats were used and randomly divided into 10 groups, i.e. normal control, 1 PBH (postburn hour), 3 PBH, 6 PBH, 12 PBH and 24 PBH groups of smoke inhalation injury, 6 PBH and 12 PBH groups with dexamethasone treatment, and 6 PBH and 12 PBH groups with chloroquine treatment. The lung water content (LWC), pulmonary vascular permeability (PVP) and hemorrhagic amount (PHA) were measured.

RESULTS

The LWC and PVP (measured by the pulmonary exudation amount of (131)I -- labelled albumin) increased obviously, peaked at 6 PBH and lasted to 24 PBH (P < 0.01) in rats injured by smoke inhalation. In groups treated with chloroquine or dexamethasone, the LWC and PVP were significantly lower at 6 PBH (P < 0.05). Similarly, the PHA in injured group exhibited remarkable, especially at 1 PBH and up to 24 PBH when the value was still higher than that in normal control group (P < 0.01). In groups treated with chloroquine or dexamethasone, PHA abated evidently at 6 PBH (P < 0.01). But there were no significant difference of the indices among groups at 12 PBH.

CONCLUSION

Both chloroquine and dexamethasone be effective in preventing and treating pulmonary edema in rats in the early stage of smoke inhalation injury.

[Treatment of severe inhalation injury with endotracheal infusion of exogenous pulmonary surfactant]

OBJECTIVE

To explore the possibility and the effects of clinical application of exogenous pulmonary surfactant (PS).

METHODS

Two burned patients with severe inhalation injury were treated with 5% emulsified porcine PS by endotracheal infusion of 10 ml every 2 hours with the assistance of mechanical ventilation. The indices of patients' oxygenation and related pulmonary dynamics were observed.

RESULTS

Twenty-four hours after the application of exogenous PS, PaO(2) and PaO(2)/FiO(2) increased evidently, but (A -- a) DO(2) and RI decreased obviously and PaCO(2) sustained for the observing period. The index related pulmonary dynamics, DeltaV/DeltaP increased gradually.

CONCLUSION

With the assistance of mechanical ventilation, endotracheal infusion of exogenous PS could improve oxygenation and compliance of patients with severe inhalation injury. And the patients exhibited very good tolerance to exogenous PS.

[Microsurgical treatment of large or giant aneurysms in anterior circle of Willis]

OBJECTIVE

To improve the operative results in large or giant aneurysms of the anterior circle Willis.

METHODS

Retrospective analysis was performed on 28 patients with large or giant aneurysms of the anterior circle Willis after operation. Three-D CT angiography was used to detect and delineate aneurysm preoperatively. Improved operative technique included cranial base approach, temporary artery occlusion, intra-aneurysm decompression, obliteration of aneurysm with multiple clips, stepwise coagulation clipping and resection of aneurysms.

RESULTS

Good results were noted in 24 patients (85.7%), fair in 2, and poor in 1. One patient died, but no patient with Hunt and Hess 0-III grade died.

CONCLUSIONS

Three-D CT angiography is useful in delineating the shape, size, neck of aneurysms, and their relation to near arteries and to cranial base structures. These are helpful to improve operative results of large or giant aneurysms of the anterior circle of Willis.

Modified sternal elevation for children with pectus excavatum

OBJECTIVE

To describe our experience in the treatment of pectus excavatum (PE) using a modified sternal elevation procedure.

METHODS

From Oct. 1986 to Dec. 1997, 171 patients with PE were admitted to the Department of Pediatric Surgery of the First Hospital of West China University of Medical Sciences. All patients were diagnosed through a history and physical examination. Cardiopulmonary function was assessed by M-mode echocardiography and instrument of pulmonary function in 40 patients before and 4.2 years after surgery which was performed between 1989 and 1994. We performed the following three procedures in the sternal elevation: (1) forming the metal strut in a "arch" shape, (2) suturing the perichondrium into a "pipe" shape, and (3) encouraging patients to do chest expansion exercise after operation. All patients were followed up for 1 to 12 years.

RESULTS

The normal contour of the costal cage was enlarged in all but one patient. Exercise tolerance was improved, and cardiac function recovered to the same level as in healthy children, while pulmonary function recovered very slowly after surgery.

CONCLUSION

The normal appearance of chest wall can be recovered and normal cardiopulmonary function can be restored by the modified sternal elevation procedure in children with PE.

Phytic acid as an efficient low-molecular-mass displacer for anion-exchange displacement chromatography of proteins

Phytic acid, inositol-hexaphosphoric acid, molecular mass 650, a low-molecular-mass compound, has been identified as a nearly ideal displacer in anion-exchange displacement chromatography for the concentration and purification of model protein mixture. The concentration of low-molecular-mass displacer is a very important parameter for successful separation by displacement chromatography. Displacer concentration influences the formation of the isotachic train and the yield and recovery of the displacement chromatographic process. There is an optimum displacer concentration in which the yield and recovery are highest.

Increased protein loss during peritonitis associated with peritoneal dialysis is neutrophil dependent

BACKGROUND

Peritonitis in peritoneal dialysis patients is accompanied by an enhanced migration of neutrophils (PMNs) and increased protein loss into the peritoneal cavity; however, the role of PMNs in governing increased protein loss during peritonitis associated with peritoneal dialysis is unknown.

METHODS

We determined the importance of PMNs in governing changes in peritoneal permeability to protein in New Zealand White rabbits in which acute peritonitis was induced by adding 4 x 106 colony-forming units of Escherichia coli to 35 mL/kg of 0.9% saline dialysate. The total leukocyte and PMN migration into the peritoneal cavity was assessed by differential cell counts in the dialysate, and peritoneal permeability to protein was evaluated by calculating the dialysate to plasma concentration ratio for total protein as a function of time during a six- or eight-hour dwell. In series 1 experiments, leukocytes were depleted from the rabbit circulation by an intravenous injection of mustine (1.2 mg/kg) three days before the experiment; in series 2 experiments, integrin-dependent PMN migration into the peritoneal cavity was inhibited by an intravenous injection of monoclonal antibody (mAb) 60.3 (2 mg/kg) directed against the integrin CD18 on leukocytes five minutes before the experiment.

RESULTS

In series 1 experiments, mustine decreased circulating leukocytes by 82 +/- 5% (mean +/- SEM) and circulating PMNs by 93 +/- 3%. Total leukocyte and PMN migration into the peritoneal cavity and peritoneal permeability to protein were decreased in mustine-treated rabbits after exposure to E. coli in the dialysate to levels similar to those found in rabbits without bacterial peritonitis. In series 2 experiments, an intravenous injection of anti-CD18 antibody also abrogated both the enhanced PMN migration into the peritoneal cavity and the increased peritoneal permeability to protein after exposure to E. coli in the dialysate.

CONCLUSIONS

PMN migration into the peritoneal cavity is integrin dependent. Increased protein loss during acute, gram-negative bacterial peritonitis in a rabbit model of peritoneal dialysis is PMN dependent.

[Isolation and purification of Lycium barbarum polysaccharides and its antifatigue effect]

A purified component of lycium barbarum polysaccharide (LBP-X) was isolated from lycium barbarum L. by DEAE ion-exchange cellulose and sephacryl gel chromatography. LBP-X was tested on five different doses (5, 10, 20, 50 and 100 mg.kg-1.d-1) in mice. The results showed that LBP-X induced a remarkable adaptability to exercise load, enhanced resistance and accelerated elimination of fatigue. LBP-X could enhance the storage of muscle and liver glycogen, increase the activity of LDH before and after swimming, decrease the increase of blood urea nitrogen (BUN) after strenuous exercise, and accelerate the clearance of BUN after exercise. The dosage of LBP-X 10 mg.kg-1.d-1 was the best amount among the five tested doses.

Cellular delivery of functional peptides to block cytokine gene expression

Advances in molecular and cellular biology have identified the cellular mediators that regulate many disease processes and have facilitated the development of new therapeutic agents that control these events. However, the size, complexity, and cellular inaccessibility of these therapeutic agents make their cellular delivery difficult. Here, we describe an efficient cellular delivery system that exploits the membrane-translocating ability of signal peptides to import functional peptides into cells. Molecular conjugates consisting of the signal import peptide (IP) and nuclear localization sequence (NLS) of the transcription factor NF-kappaB were synthesized. Electrophoretic mobility shift and enzyme-linked immunosorbent assays were used to assess the inhibitory effects of these synthetic peptides on agonist-induced NF-kappaB nuclear translocation and transcriptional activation. Our results indicated that the peptides were effective in inhibiting both the nuclear translocation and transcriptional activation of NF-kappaB. However, their effects required the presence of the IP moiety for efficient cellular entry of the NLS. Structural analysis of IP showed that the hydrophobic domain, and to a lesser extent the N-terminal domain, was responsible for the membrane translocating activity of IP.

[Study of graft-versus -leukemia activity of gamma-ray irradiated haplomismatched donor lymphocytes infusion]

OBJECTIVE

To explore graft-versus-leukemia activity of 7.5 Gy gamma-ray irradiated haplomismatched donor lymphocytes infusion (DLI).

METHODS

L615 cells loaded 615 (H2(k))/BALB/c (H-2(d)) F(1) mice were infused with irradiated haplo-mismatched donor lymphocytes at 3, 5, 7 days after CTX (200 mg/kg) treatment which was given at the 3rd day after L615 cells inoculation.

RESULTS

T-cells irradiated with 7.5 Gy gamma-ray lost their proliferative capacity but preserved their cytotoxic activity against allogeneic targets. Survival of these recipient mice was longer than that of control (t = 10.03, P < 0.001) with no severe graft-versus-host disease (GVHD).

CONCLUSION

7.5 Gy gamma irradiation attenuated the GVHD inducing potential of allogeneic lymphocytes while preserving their graft-versus-leukemia activity. It provides a simple modality to postpone and prevent leukemia relapse.

[Effect of intravascular low level laser irradiation used in avulsion injury]

OBJECTIVE

To explore the effect of intravascular low level He-Ne laser irradiation on skin flap survival after orthotopic transplantation in avulsion injury.

METHODS

Fifty eight cases suffered avulsion injury were treated by debridement and orthotopic transplantation of avulsed flap within 6 hours, 31 of them were received intravascular low level He-Ne laser irradiation and routine treatment, and 27 of them were received routine treatment as control group.

RESULTS

The survival area and quality of avulsed flap in the experimental group were superior to that of control group after 15 days of operation, and the hemorheological items were markedly changed at 5 days after operation.

CONCLUSION

The better flap survival after orthotopic transplantation in avulsion injury can be improved by intravascular low level He-Ne laser irradiation through changed superoxide dismutase activity and hemorheological items in optimal irradiation intensity.

[Study on the removal of arsenic from drinking water by coagulants]

The coagulation method for removing arsenic in drinking water from dispersed water supply was tested. The results showed that the remained arsenic [As(V)] in decanted water could be lower than 0.05 mg/L by directly putting 50 mg/L ferric sulfate into water samples without adjusting pH value (pH 7.82) and settling for 12 hours in room temperature while the original As(V) concentration was 1.0 mg/L. The same removal efficacy could be achieved by putting 30 mg/L ferric sulfate or 40 mg/L aluminum sulfate and filtering after 30-40 min settlement. The removal rates were raised with the increased concentration of coagulants in water. The remained As(V) in filtered water could meet the valid health standard of drinking water (< 0.05 mg/L) when the original concentrations of As(V) were 1.0 mg/L and 0.5 mg/L by using 30 mg/L ferric sulfate and aluminum sulfate respectively. Furthermore, ferric sulfate was more efficient than aluminum sulfate at varied of pH value, water temperature, turbidity and hardness of water, etc. Generally, arsenic in coagulated sludge would not release into water again.

Structure-based ligand design by dynamically assembling molecular building blocks at binding site

A structure-based ligand design method is proposed and tested. The method is based on stochastic dynamics simulation of multiple copies of molecular building blocks in the presence of a receptor molecule. The molecular building blocks are assembled into candidate compounds "on the fly" at given intervals during the simulation. In the algorithm, a special effort is made to explore different possible combinations of building blocks and to select an optimum combination. By repeating the cycle of deconstruction and reconstruction in a single simulation, a set of candidate compounds that can be built from the building blocks evolves and is dynamically optimized. The method was tested by breaking two known flexible human immunodeficiency virus type 1 protease inhibitors into building blocks and reassembling them in the active site of the enzyme. For the inhibitor L700417, a set of conformations was generated by the calculation. Among these, the original compound was recovered with the lowest energy at the experimentally observed binding site and in the correct conformation. For pepstatin, the experimentally observed binding mode of the backbone of the inhibitor was reproduced by a calculation in which the building blocks corresponding to the side-chain groups were omitted. Proteins 1999;36:462-470.

Time-dependent changes in dough color in hexaploid wheat landraces differing in polyphenol oxidase activity

Time-dependent changes in the color of noodle sheets (using 2% NaCl or 1% alkaline salts in the formulation) made from 43 Iranian hexaploid wheat landrace accessions were measured. Pekar slick tests in water and in alkaline conditions were also carried out. A wide variation in color characteristics of the landraces was found, with L values of salted noodle sheets at 2 h ranging from 80.9 to 89.2 and b values of alkaline noodle sheets at 2 h ranging from 19.1 to 27.4, showing potential application in noodle wheat improvement programs. For initial rapid screening of samples it was observed that a single reading of the dough sheet after 2 h was adequate. The dough sheets should be kept at 5 degrees C during storage, to prevent microbiological activity in the dough, which would give erroneous results. The Pekar slick test results were not highly correlated to color measurements on the dough, so this test is not recommended for screening for noodle color potential in landraces.

[A study on pathology and immunoglobulin of orbital tissues from cases with Grave's ophthalmopathy]

OBJECTIVE

To investigate pathological changes and the expression, localization of immunoglobulins (IgA & IgE) in orbital tissues from patients with Grave's ophthalmopathy.

METHODS

Orbital tissues were obtained at surgery from 19 patients with Grave's ophthalmopathy and 17 control subjects. Immunohistochemical studies were carried out by using anti-IgA, anti-IgE antibody and a streptavidin-biotin-peroxidase detection system. In addition, hematoxylin-eosin, alcian blue and Masson trichrome stains were employed to demonstrate the pathologic changes in the tissues.

RESULTS

12 of 17 samples from patients exhibited IgA positive staining for the connective tissue associated with the extraocular muscles and orbicularis oculi, however only 2 control muscles reacted minimally. IgE positive material was found in association with the majority of leukocytes and with muscle fibers in 13 patients, but only 4 control subjects displayed mild reactions. Significant expression of IgE was more often demonstrated in patients with eye disease of short course than in those of longer course.

CONCLUSION

These results support the notion that the eye muscle fiber and fibroblast are important targets of the orbital autoimmune reaction in Graves' ophthalmopathy in which IgA and IgE both play important roles.

[Observation of special stain and ultrastructure of lattice, granular and macular corneal dystrophy]

OBJECTIVE

To investigate the histopathological changes of lattice, granular and macular corneal dystrophy.

METHODS

Corneal buttons were obtained from penetrating keratoplasty due to severe corneal dystrophy, and their sections and ultrathin sections with several special stains were observed under a light microscope (LM) and electron microscope (EM).

RESULTS

In cases with lattice dystrophy, the stromal fusiform deposits seen under LM were confirmed to be amorphous materiel with filaments by EM and stained positively for Masson trichrome, PAS and Congo red. In cases with granular dystrophy, the granular or bread debris deposits found between laminae under LM were extracellular material observed by EM and they were stained positively for Masson trichrome and alcian blue. In cases with macular dystrophy, the stromal spheroid or macular deposits were seen under LM, and there were numerous vacuoles containing fibrils and granules in the cytoplasm of keratocytes and accumulative amorphous material in the stroma under EM; the deposits were positive for colloidal iron and alcian blue stain.

CONCLUSION

In corneal lattice dystrophy, there are amyloid deposits; in granular dystrophy, there are extracellular material deposits; and in macular dystrophy, there is mucopolysaccharide accumulation.

[Effects of pure and crude Lycium barbarum polysaccharides on immunopharmacology]

Effects of pure Lycium barbarum polysaccharides (LBP-X) on immunological activity were compared with crude LBP. The pure LBP-X were divided into different doses, lower doses (5-20 mg/kg.d) of pure LBP-X showed a remarkable effect on immunological enhancement. Especially, LBP-X 10 mg/kg.d had a highly significance difference compared with crude LBP on immune indices in mice. Lycium barbarum polysaccharides have the best pharmacological effect when it was the best dose.

[The restoration of the "double peak" in OCT images based on inverse Wiener]

It has been found that the high reflectivity film of the reference mirror in OCT may cause a socalled "double peak effect" in the result images. To eliminate this a restoration algorithm is proposed here. The method is based on the mathematical modals of the point-spread function of OCT with consideration of double peak effect. The power spectrum of the noise and signal are estimated by the average smooth periodogram method. An inverse wiener filter algorithm, which avoids the illness condition in common inverse filter, gives the final restored images. The algorithm is also capable of the image degrading recovery due to the aberration and the band-limited spectrum.

[Gas-sensing transmittivity spectrum of two-dimension SnO2: TiO2 compound film in ammonia vapor]

In this paper, we studied the gas-sensing transmittivity spectrum of the two-dimension SnO2: TiO2 compound film in ammonia vapor. It was observed that when the gas concentration was relatively low the transmittivity decreased as the gas concentration decreased, and when the gas concentration was relatively high, the transmittivity increased as the gas concentration increased. We considered the effect of the wet vapor, and explained this phenomenon.

[Cloning and sequencing of fusion protein gene of recombinant GM-HBsAg]

GM-CSF is an effective adjuvant for immunology, it was used to improve the immunological function of antigen and to increase the anti-HBs responses. Through using polymerase chain reaction (PCR) technique, we amplified 384 bp and 846 bp gene fragments from GM-CSF and HBsAg. The products were extracted and purified; a 1230 bp gene fragment was obtained by T4 DNA linkage. This amplified product was cloned into pUC19 vector. The positive clones were screened and the inserted fragment was determined by restriction enzymes. The gene fragment length determined is 1230 bp, the sequence analysis showed that the gene fragment is GM-CSF-HBsAg gene. The successful construction of GM-HBsAg fusion protein gene provides basis for research of its biological activity and expression.

[Effects of the serum obtained from smoke inhalation injury rats on PMN adhesion and transmigration in vitro]

OBJECTIVE

This study was conducted to determine the changes in PMN adhesive capacity to endothelial cells and transmigration through endothelial cell (CEC) sheet in the presence of the serum from rats with smoke inhalation injury (SII). The effects of adhesion molecules CD11a, CD11b, and ICAM-1 on the PMN adhesion and transmigration were also studied.

METHOD

In the present study fluorescent assay, EC sheet cultured on the 5 microns permeable membrane and antibody blocking technique were used to study the PMN adhesion and transmigration in vitro.

RESULT

It was found that the serum from SII rats could promote PMN adhesion to CEC sheet. After being cultured with the serum for 12-24 h, PMN adhesion to CEC was more than three times of that in control. The serum also enhanced PMN transmigration through the CEC sheet in vitro, doubling the amount observed in control when the sheet was cultured with the serum for 24 h. Based on the above data it was believed that the SII rat serum could enhance PMN adhesion to and transmigration through lung capillary, and the percentages of PMN adhesion and transmigration were found to be positively correlated (r = 0.975). Furthermore, the antibodies against CD11a, CD11b, and ICAM-1 reduced PMN adhesion 44%, 55% and 51%, respectively, and at the same time decreased PMN transmigration 39%, 65%, and 58%, respectively.

CONCLUSION

In the presence of serum obtained from SII rats PMN adhesion to and transmigration through CEC sheet increased, which is the possible underlying mechanism responsible for PMN infiltration in vitro. Moreover, the adhesion molecules such as CDA11a, CD11b, and ICAM-1 play an important role in the process. Infiltrated PMN could release oxygen free radicals and protease to injure lung tissue.

[Production of allochtonic formations in callus cells of Salvia miltiorrhiza Bge]

OBJECTIVE

To study the effect of hormones content in the medium on of allochtonic formations in the callus from Salvia miltiorrhiza.

METHOD

Study the development of allochtonic formations in the callus from explants of Salvia miltiorrhiza cultured on hormones of different content ratios in the medium.

RESULT AND CONCLUSION

2,4-D inhibits the production of water-soluble active principles and KT promotes the production of total tanshinone.

[The real-time classification of motor unit potentials]

Motor unit potentials(MUP) are real-time classified with the method of correlation in this paper. The correlation coefficients are sorted to reserve the better waves of MUP. Not only the store waves and analytical time of MUP can be reduced, but also the measurement correction and precision of MUP parameters can be improved.

Thin-layer ion-exchange chromatography of proteins

Thin-layer chromatography (TLC) is one of the simplest and most convenient techniques to separate small molecules. Of a variety of TLC separation modes, only size-exclusion was successfully used to separate proteins. In this paper, adsorption-TLC was used to separate proteins. The net charges were calculated for four model proteins, albumin, transferrin, lactoferrin and lysozyme, under different pH values. The suitable pH values for separation were determined according to the results from such calculations. Then, the adsorption isotherms of the four proteins were measured to deduce the ionic strength for appropriate elution conditions. Optimal conditions, 0.01 M bicine and pH 8.50, and a three-step elution process (1st step 0.01 M NaCl, 2nd 0.025 M NaCl, and 3rd 0.10 M NaCl), were obtained. Finally, the four model proteins were successfully separated under these elution condition.

[The influence of adhesion molecules expression to neutrophil aggregation in liver after severe burns]

OBJECTIVE

To elucidate the mechanism of neutrophil aggregation in the liver and the influence of the expression of adhesion molecules after severe burns during early postburn phase, and to explore simultaneously the mechanism of liver damage after severe burns.

METHODS

1. The morphology of the liver and the activation of MPO were observed. 2. The human hepatocytes and hepatic sinusoidal endothelial cells (HSECs) were isolated and cultured, the flow cytometry and micropipette aspiration system were used to observe dynamically the change in intercellular adhesive force between neutrophils and hepatocytes under the influence of burn patient sera. Also the changes in the expression of P-selectin and ICAM-1 on the hepatocytes and HSECs under the influence of burn patient sera were studied.

RESULTS

1. MPO activation was significantly higher than that in the control group, and reached its peak at 6 hours. Three pieces of liver tissue at 6, 12, 24 hours were examined, and it was found that the Disse's spaces were wide and filled with a great number of PMNs. 2. A constitutive expression of P-selectin and ICAM-1 was found in normal hepatic sinusoidal endothelial cells but not in normal hepatocytes. Under the influence of burn patient sera, the expression of P-selectin increased significantly at 1 hour (P < 0.01) in hepatic sinusoidal endothelial cells but not in hepatocytes, and the expression of ICAM-1 increased significantly at 1 and 2 hour (P < 0.01) in hepatocytes and hepatic sinusoidal endothelial cells. 3. In the presence of burn patient sera, the intercellular adhesive force between neutrophils and hepatocytes reached its peak level at 2 hour after co- cultivation and declined thereafter due to the aggravation of hepatocytic injury. After using ICAM-1 Mab in cultured hepatocytes, the adhesive force reduced significantly.

CONCLUSION

Neutrophil aggregation in the liver was confirmed after severe burns during early postburn phase. The expression of P-selectin and ICAM-1 on the hepatocytes and HSECs played key roles to neutrophil aggregation in liver after severe burns during early postburn phase, inducing the participation of neutrophils in hepatocyte injury.

Human brain functional imaging with reflectance CWS

Continuous Wave Spectroscopy (CWS) has been used in human subjects to detect brain function by observation of brain oxygenation and blood volume changes. In this research, we have developed a device for imaging brain oxygenation and blood volume with multiple sources and detectors in an area of 10 x 12 cm. Twelve, 1 watt tungsten bulbs were used as a light source, together with 8 detectors consisting of silicon-photodiodes with band-pass filters at 760 and 850 nms. The detectors were placed on a model system of the human head, providing 16 source-detector combinations with 4 cm separation. Eight to 16 seconds were required to image a brain function. Models using resin and a black object which have similar optical characteristics to a brain were studied. The model study showed that we can detect changes in absorption as deep as 2 cm from the surface. Human subjects with relatively thin hair, who volunteered for this study, were asked to tap fingers and rest, or to observe light flashing and darkness alternatively for 10 to 20 minutes while the images were being taken. In the finger tapping, the blood volume increased in a small, 1-2 cm area, while in the light stimulation, a much larger area was affected with a greater increased blood volume. Oxygenation occurred also in the area where blood volume increased. We concluded that the CWS can be used to image the location of brain activity by means of blood volume increase and oxygenation. In addition, brain disfunction and diseases, such as learning disability and brain hematoma may be detected with this imaging device.

[Esophageal reconstruction using ilecolon in children--a report of ten cases]

The use of the ileocolon as a substitute for esophagus in children has been a well-established surgical procedure. Between 1992 and 1995, ten retrosternal esophageal substitutions using an ileocolic interposition were performed. The ages of the children ranged from 2 to 8 years. The esophageal strictures were secondary to ingestion of caustic liquid. No death occurred in the intra- and post-operation period. Cervical ileoesophageal anastomotic leaks took place in 2 cases as the early major postoperative complications, which healed spontaneously. Three cases of ileoesophageal anastomotic strictures were noted in the follow-up period. The surgical indications, the treatments of anastomotic leaks and strictures, and the importance of long-term follow-up were discussed.

[The observation on infection of trasgenic mice (PVR Tg21) with polioviruses type 3]

OBJECTIVE

To test and verify whether PVR Tg21 transgenic mice can be used as an animal model or not.

METHODS

PVR Tg21 transgenic mice were infected with 3 poliovirus strains with different neurovirulence intraspinally.

RESULTS

All the mice showed clinical paralysis with characteristic lesions in neurons. The symptoms varied with different potency of virus. The onset of clinical paralysis time for inoculated mice were approximately 2 days with Leon virus, 5 days with Sabin strain, and 4 days with Vaccine-321. More than 90% of mice inoculated with Leon strain died within 3 days after clinical paralysis and only 35% mice inoculated with Sabin-3 died at average of 6 days, and the PD50 are 10(1.1), 10(2.6), and 10(4.97) TCID50 and LD50 are 10(1.1), 10(3.33) and 10(5.33) TCID50, respectively. Different virus inoculated intraspinally caused different histopathological lesions.

CONCLUSIONS

The PVR Tg21 transgenic mice could be a new animal model for neurovirulent evaluation of poliovaccines and epidemiological surveillance.

[Design of the ECG recording system based on ISD2500 series voice chips]

An ECG recording system based on voice chip ISD2560 is introduced. According to the frequency range of ECG, we make the best use of the ISD2500 series voice chips. This device can easily record patient's ECG for clinical diagnosis.

[Expression of ferritin receptor on placental microvillous membrane and its role in maternal-fetal iron transport]

OBJECTIVE

In order to investigate the expression of ferritin receptor (FnR) on human placental microvillous membrane in mid-pregnancy and its implication.

METHODS

Radioligand binding assay was used, with horse spleen 125I-apo-ferritin as radioligand.

RESULTS

The FnR expression in normal placental microvillous membrane in mid-pregnancy was (9.63 +/- 4.72) x 10(12) sites/mg pro, similar to that in normal placental of term delivery,and the dissociation constants (Kd) between them had also no significant difference: Competitive binding assay indicated that the receptor bound basic ferritin with higher affinity than acidic one.

CONCLUSIONS

The expression of FnR in mid-pregnancy almost come to mature level; The FnR on placenta might be involved in maternal-fetal iron transport, transfering iron from mother to fetal.

[The technology of real time telemetring and monitoring multi-channels ECGs through public telephone network]

In this essay a kind of technology of real time telemetring and monitoring multi channels ECGs through public telephone network is presented. Two limb leaders (I and II) ECG signals are transmitted from the sender at first. After they are received by the receiver the other four limb leaders are calculated by computer in the basis of the relation among the limb leaders, the received waveform and the calculated waveform are just the same as those described directly by Electro Cardiograph. After the limb leaders ECG signals (34 s) are transmitted, two selectable thorax leaders ECG signals are transmitted for 34 seconds after automatically changing the leaders. The received ECG waves are displayed on screen real time, shifting smoothly. After transmission doctors may make diagnoses and give some suggestion for treatment. Thus, telemetrying and monitoring multi channels ECGs is realized.

Optical investigations of physiology: a study of intrinsic and extrinsic biomedical contrast

The utility and performance of optical studies of tissue depends upon the contrast and the changes of contrast in health and disease and in functional activity. The contrast is determined both by the optical properties of extrinsic chromophores and scatterers but especially upon the changes evoked by physiological activity and pathological states. Here, we have focused upon absorption changes of the intrinsic probe, blood absorbance changes due to cortical hypoxia and to haematomas, giving, for particular conditions, absorbance changes of 0.15 and over 0.4 delta OD, respectively. Functional activity may give changes of blood volume of over 0.05 delta OD with some variability due to individual responses that is best expressed as histogram displays of the distribution of response among a significant population. Responses have been observed in prefrontal parietal and occipital functions (242 tests). Extrinsic probes afford signals dependent upon the dose tolerance of the subject and can readily equal or exceed the blood volume and oxygenation signals, and currently afford vascular volume and flow indications. However, contrast agents for the functional activity of cellular function are ultimately to be expected. Finally, light-scattering changes afford osmolyte-related responses and are here shown to indicate a larger signal attributed to cortical depolarization and K+ release in hypoxia/ischaemia. Thus, the optical method affords imaging of manifold contrasts that greatly enhance its specificity and sensitivity for diagnostic procedures.

[Measurement and analysis of tumor tissue autofluorescence spectra]

Measurement results of laser induced autofluorescence spectra of tumor tissue from little rat are given in this paper it is compared with normal tissue of the same body After analyzing the origin of tumor tissue autofluorescence and the difference with normal tissue spectra, it is concluded that autofluorescence spectra of tissue may reflect the features of tumor tissue and be utilized to diagnose the tumor.

[Detection of mRNA expression of endothelin-1 in organs on severe burn rat model with in situ hybridization technique]

After the dynamic observation of postburn endothelin changes in plasma on severe burn rat model, we detected ET-1 mRNA expression and cell localization in some organs such as heart, lung, liver and kidney with in situ hybridization technique. We that endothelin concentration in plasma rapidly increased postburn (it reached its climax at 6th hour and maintained fairly high level even at 24th hour postburn). Meanwhile in situ hybridization indicated that ET-1 mRNA expression intensity and number of positive cells rapidly increased postburn. The expression climaxes of which appeared decreasing in turn from kidney, liver, lung to heart and the types of positive cells increased. This may due to the endothelin's functions of contracting blood vessels and regulating the redistribution of blood flow and be helpful for guaranteeing blood perfusion of important organs under shock state, but the overexpression of ET-1 mRNA may make the ischemic and anoxic damages to organs more severe.

[The development of ECG trans-telephone popular monitoring system]

In this essay a new kind of ECG telemetry and monitoring system based on public telephone network is presented, which is able to transfer four channels of ECG of two patients to monitoring center sited at hospital synchronizingly. At the same time doctors may make diagnosis and give instruction for treatment. The system has the functions of real time sample, reviewing, freezing, store, windows, and printing, etc.

[Effect of light colours and illumination intensity on the sexual behaviour of Hepialus gonggaensis Fu et Huang]

The sexual behaviour of Hepialus gonggaensis has close relations with ecological environment and varies with its ecotypes. The more intense the illumination, the faster the sexual drive of Hepialus gonggaensis begins and the longer its sexual intercourse continues, light colours have a bearing on its sexual intercourse time. This study has provided an evidence for the artificial cultivation of Hepialus gonggaensis.

Intravitreal tolerance of a new perfluorocarbon vitreous replacement, Multifluor APF-144

OBJECTIVE

To evaluate the intravitreal tolerance of a new perfluorocarbon vitreous replacement, Multifluor APF-144 (perfluorotetramethylcyclohexane).

DESIGN

Ten New Zealand albino rabbits (one eye from each) underwent vitrectomy. The vitreous was replaced in five eyes with Multifluor APF-144 and in five eyes with saline (control group).

OUTCOME MEASURES

Appearance on indirect ophthalmoscopy, electroretinography recordings before and 2, 4 and 8 weeks after vitrectomy, findings on electron and light microscopy at 8 weeks.

RESULTS

Endophthalmitis did not develop in any of the eyes. There was no significant change in electroretinography values for the experimental eyes after vitrectomy. No evidence of retinal toxicity was found on light or electron microscopic examination.

CONCLUSIONS

Multifluor APF-144 shows promise as a short-term postoperative retinal tamponading agent.