Biomedical subjects
Publications and source records attributed to J Lu.
The quality control methods of the seed oil and fruit oil of Hippophae rhamnoides are studied. The physical and chemical factors are determined and the identification and determination methods for the bioactive compnents a-tocopherol and carotenes are established.
In this study,four different kinds and three different length elastomeric chains were tested to compare their force delivery properties.It suggested that different kind and length chains should be selected to generate optimal orthodontic forces clinically.
In this study,methods were developed to test and compare leveling archwires that commonly used in domestic practice.The results showed that the stainless steel arch wires were stiff.The Ni-Ti wires and the wires with loops were flexible and could deliver more constant force.The 0.014 Chinese Ni-Ti wires demonstrated the superelastic property,but 0.016 Ni-Ti wire did not appear the same property before they generated 250g force.
In this study,some different kinds of orthodontic archwires were tested to evaluate the changes of their mechanical properties.The results showed that in oral environment,all wires suffered degradation of their properties:the force-generating capacity decreased and the permanent deformation increased.The force-generating capacity decreased and the permanent deformation increased.The force decay resulted mainly from the tooth movement.The deformation occurred within 7 days.Chinese-NiTi alloy suffered less stress-relaxation and residual deformation than the stainless steel wires.Arch wires with vertical loops showed similar properties with NiTi,which could deliver more constant force.
Anti-HCV IgG is the routine assay for the diagnosis hepatitis C. But the method is ineffective in early detection of hepatitis C. We have detected anti-HCV IgM in hospital hepatitis C patients by Enzyme-Linked Immunosorbent Assay (ELISA) and compared the results with those of HCV-RNA and total antibody. Our studies indicate that anti-HCV IgM is detected in all hepatitis C marker positive sera. But the amount of anti-HCV IgM in HCV-RNA positive sera is significantly higher than that of in the corresponding negative sera. This subjects that anti-HCV IgM and HCV-RNA are somewhat correlated and they have different clinical interests. Anti-HCV IgM can be expected and hepatitis activities and its actual clinical interests are to be further studied.
The solid-phase enzyme immunoassay (EIA) was used for detecting anti-HEV immunoglobulin G (IgG) and M (IgM) by using a recombinant chimeric antigen (ORF3-2) from the open reading frame (ORF) 2 and 3 of hepatitis E virus gene. These sera were collected from the patients with sporadic acute viral hepatitis. The positive rate for anti-HEV IgG was 15.22% (7) among 46 patients with acute hepatitis, 5 of the 7 IgG positive sera were also positive (71.4%) for anti-HEV IgM. 91.8% (93) and 76.4% (78) were positive separately for anti-HEV IgG and IgM among 102 patients of suspected HEV infection (these patients were negative for anti-HAV, anti-HBV and anti-HCV), about 2/3 patients of HEV infection detected were simultaneously HEV-IgG and IgM positive. In control group of 98 normal persons, 4 (4.08%) were positive for anti-HEV IgG, but none were IgM positive. Paired sera of the patients in the acute phase and convalescent phase were detected, the titers of anti-HEV IgG with 4-16 fold decrease were seen in 6 cases and with 2-fold rise in 1 case.
Raman scattering measurements of the cathode deposite produced by carbon arc discharge method and graphite was repotred. The results indicate that the inner core of the deposite containing large quantities of carbon nanotubes undergoing crystallization process. Carbon nanotube is one kind of micro-crystal of quasi-graphite.
This paper studied the near-infrared spectra of liquid samples. The plots of weights at each wavelength showed the spectral characteristics of pure materials. The samples could be classified by using plots of the scores of their first principal components. The principal component regression of samples was made. The obtained results were identical with the reference analytical values. The advantages of near-infrared spectroscopy, combined with principal component analysis, lie in its nondectructivity for samples and suitability for on-line measurements.
Morphometric analysis of 54 dry cervical spines from C3 to C7 (a total of 270 cervical vertebrae) and bilateral dissection of 10 anatomic specimen cervical spines were performed. The uncinate processes were significantly higher at C4 to C6 (5.8 +/- 1.1 mm to 6.1 +/- 1.3 mm) levels than at C3 or C7 levels. The anteroposterior diameter of the intervertebral foramina was smaller at the C4, C5, and C6 levels compared with that at the C3 or C7 levels. The length of nerve root between the lateral border of dural tube and medial border of vertebral artery gradually increased from C3 (3.3 +/- 1.1 mm) to C7 (8.1 +/- 2.1 mm). A combination of higher uncinate process, smaller anteroposterior diameter of intervertebral foramina, and longer course of nerve roots in close proximity of the uncovertebral joints at the C4 to C6 levels may explain the predilection of nerve root compression by uncovertebral osteophytes at these levels. The distance from apex of the uncinate process to medial border of the transverse foramen gradually increased from C3 (1.7 +/- 0.8 mm) to C7 (3.3 +/- 1.0 mm), which may predispose the midcervical level to compression of the vertebral artery by laterally projecting uncovertebral osteophytes.
The lumbosacral plexus was dissected bilaterally in 20 adult cadavers to define the anatomic relationship of the lumbosacral plexus to the sacrum and the sacroiliac joint. All results are mean values +/- standard deviation. The length of the nerve roots of the lumbosacral plexus gradually decreased from L-4 to S-3 (from 93.8 +/- 6.9 mm in males and 108.7 +/- 7.7 mm in females at L-4 to 43.7 +/- 4.3 mm in males and 49.0 +/- 7.6 mm in females at S-3). The angle projected by the nerve roots of the lumbosacral plexus with respect to the sagittal plane gradually increased from L-4 to S-3 (from 14.3 degrees +/- 3.4 degrees in males and 16.7 degrees +/- 4.8 degrees in females at L-4 to 51.8 degrees +/- 9.0 degrees in males and 57.8 degrees +/- 9.1 degrees in females at S-3). The width of the nerve roots of the lumbosacral plexus was greatest at S-1 (9.8 +/- 1.8 mm in males, 8.6 +/- 1.5 mm in females). The L-5 nerve root was the thickest in males (4.4 +/- 0.5 mm), and the S-1 nerve root was thickest in females (4.3 +/- 0.4 mm). The lumbosacral trunk was 30.0 +/- 9.0 mm in length in males and 32.0 +/- 6.0 mm in females; 11.4 +/- 1.8 mm wide in males and 11.2 +/- 1.5 mm in females; and 4.4 +/- 0.5 mm thick in males and 4.0 +/- 0.6 mm in females. The fifth lumbar nerve root and lumbosacral trunk coursed across the sacroiliac at a level 2.0 +/- 0.2 cm below the pelvic brim and were relatively fixed to the sacral ala with fibrous connective tissue.
In this study, an epoxy-fixed porcine pericardial patch with or without ionically bound heparin was evaluated in a canine model as an alternative to the glutaraldehyde-fixed biological patch for clinical applications. To evaluate the effectiveness of this epoxy-fixed patch, a composite membrane composed of: an epoxy-fixed porcine patch with ionically bound heparin; a glutaraldehyde-fixed porcine patch with ionically bound heparin; an ePTFE polymeric patch; a polyester polymeric patch; an epoxy-fixed porcine patch without ionically bound heparin; and a glutaraldehyde-fixed porcine patch without ionically bound heparin was made. This membrane was assessed orthopically in a canine model. The early results (1 approximately 4 weeks post implant) revealed that the biological patches with ionically bound heparin had the mildest tissue reactions (inflammatory reaction, fibrosis, and adhesion) among all the test samples. However, by 12 weeks postoperatively, all the test samples had mild to severe tissue reactions. The order of tissue reactions with increasing severity was: the biological patches with ionically bound heparin, the biological patches without ionically bound heparin, and the polymeric patches. The results suggest that heparin may be used to reduce adhesion. Additionally, the epoxy-fixed tissue caused a relatively lower degree of inflammatory reaction than the glutaraldehyde-fixed tissue.
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A number of naturally occurring products from vegetables and herbs exert chemopreventive properties against carcinogenesis. In this paper, two such compounds, isolated from garlic and from a traditional Chinese medicinal herb, are described for review. Elemene, isolated from the Chinese medicinal herb Rhizoma zedoariae, was shown to exhibit antitumor activity in human and murine tumor cells in vitro and in vivo. This novel antineoplastic agent has substantial clinical activity against various tumors. The in vitro effect of elemene on the growth of leukemia cells was evaluated by MTT assay. The IC50 values of elemene for promyelocytic leukemia HL-60 cells and erythroleukemia K562 cells were 27.5 micrograms/mL and 81 micrograms/mL, respectively, while IC50 for peripheral blood leukocytes (PBL) was 254.3 micrograms/mL. The inhibitory effect of elemene on proliferation of HL-60 cells was associated with cell cycle arrest from S to G2M phase transition and with induction of apoptosis. The apoptosis of tumor cells was confirmed by DNA ladder formation on gel electrophoresis and characteristic ultrastructural alterations. The results also demonstrated that inhibitory effects of allicin, a natural organosulfide from garlic, on proliferation of tumor cells were associated with the cell cycle blockage of S/G2M boundary phase and induction of apoptosis. These findings suggest that induction of apoptosis may contribute to the mechanisms of antitumor activity of elemene and allicin, which merit investigation as potential chemoprevention agents in humans.
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OBJECTIVE: To examine whether there is generation of oxygen free radicals (OFR) and lipid peroxidation of cell membrane after volume replacement for burn shock, and to study the relationship between OFR injury and enterogenous endotoxemia. METHODS: Forty-seven burn patients were involved in this study. Among them, 18 had delayed fluid resuscitation (DR) and the others had early fluid resuscitation (ER) within 6 hours postburn. Sixty-six gnotobiotic rats were used in a collaborating experiment as burn models. They were divided into 4 groups: sham injury (n = 6), early resuscitation (n = 24), late resuscitation (n = 24) and vitamins E and C treatment group (n = 12). All the rats, except those in the sham injury group, were inflicted with 40% total body surface area (TBSA) third-degree burns. OFR was determined in the blood of patients with electron spin resonance (ESR). S/W ratio and tau c values of patients' erythrocytes were measured with ESR spectrometer. Blood superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) activities, malondialdehyde contents and plasma endotoxin levels were assayed. Rats were sacrificed at the 12th, 24th, 48th and 72nd hour after injury. Plasma endotoxin levels, mucosal SOD, GSHPx and malondialdehyde (MDA), as well as diamine oxidase activity of ileum were determined. Cultures of mesenteric lymph nodes (MLN), liver, spleen, heart, lung, kidney and blood were done. RESULTS: A significant increase in blood OFR contents and plasma MDA, and a significant decline in blood SOD and GSHPx were found after resuscitation in DR group as compared with those in ER group. Both strong to weak spectra component (S/W) ratio and tau c value were higher in DR group in contrast with those in ER group. Higher elevation in plasma endotoxin level in DR group was seen. In DR group, plasma MDA content was correlated with S/W ratio, tau c value and plasma endotoxin level. In rats, the level of mucosal MDA, plasma endotoxin and incidence of bacterial translocation (BT) were significantly higher. Mucosal SOD, GSHPx and diamine oxidase (DAO) activity were significantly lower in DR group as compared with those in ER group. In DR group, mucosal MDA content was negatively correlated with mucosal DAO activity, while the latter was negatively correlated with BT. After treatment with vitamins E and C, mucosal MDA content decreased, plasma endotoxin and BT significantly declined and mucosal DAO heightened. CONCLUSIONS: Tissue reperfusion might induce the production of OFR, resulting in lipid peroxidation injury, especially to intestinal mucosa, and resulting in disruption of mucosal barrier function followed by endotoxemia and BT.
Myoglobin (MB) deletion from myocardium in the case of hemorrhagic shock was firstly studied by immunohistochemical and morphometry technique. The results showed that there were different degrees of segmental deletion of MB from myocardium in each case of hemorrhagic shock which has continued over an hour. The significance of these changes in forensic medicine are discussed.
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The ultrastructures of the uncinate processes (UP) obtainel from 16 patients with clinical diagnosis of chronic sinusitis were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that there were three main surface cell types on the UP: Most of the cilia was leaned, fractured and in disorder; Gaps of the cells increased obviously; Squamous cell metaplasia was seen; The endoplasmic reticulums and mitochondria in cytoplasm were expanded moderatly or seriously. The morphological changes indicated that mucus transportation functions in the anterior ethmoid region and the middle meatus were damaged. It is of great importance in occurrence and development of chronic sinusitis. The demaged nasal mucosa epithlial cells are repairable and reproducible.