TRPV1-mediated UCP2 upregulation ameliorates hyperglycemia-induced endothelial dysfunction

Background

Diabetic cardiovascular complications are characterised by oxidative stress-induced endothelial dysfunction. Uncoupling protein 2 (UCP2) is a regulator of mitochondrial reactive oxygen species (ROS) generation and can antagonise oxidative stress, but approaches that enhance the activity of UCP2 to inhibit ROS are scarce. Our previous studies show that activation of transient receptor potential vanilloid 1 (TRPV1) by capsaicin can prevent cardiometabolic disorders. In this study, we conducted experiments in vitro and in vivo to investigate the effect of capsaicin treatment on endothelial UCP2 and oxidative stress. We hypothesised that TRPV1 activation by capsaicin attenuates hyperglycemia-induced endothelial dysfunction through a UCP2-mediated antioxidant effect.

Methods

TRPV1^-/-, UCP2 ^-/- and db/db mice, as well as matched wild type (WT) control mice, were included in this study. Some mice were subjected to dietary capsaicin for 14 weeks. Arteries isolated from mice and endothelial cells were cultured. Endothelial function was examined, and immunohistological and molecular analyses were performed.

Results

Under high-glucose conditions, TRPV1 expression and protein kinase A (PKA) phosphorylation were found to be decreased in the cultured endothelial cells, and the effects of high-glucose on these molecules were reversed by the administration of capsaicin. Furthermore, high-glucose exposure increased ROS production and reduced nitric oxide (NO) levels both in endothelial cells and in arteries that were evaluated respectively by dihydroethidium (DHE) and DAF-2 DA fluorescence. Capsaicin administration decreased the production of ROS, restored high-glucose-induced endothelial dysfunction through the activation of TRPV1 and acted in a UCP2-dependent manner in vivo. Administration of dietary capsaicin for 14 weeks increased the levels of PKA phosphorylation and UCP2 expression, ameliorated the vascular oxidative stress and increased NO levels observed in diabetic mice. Prolonged dietary administration of capsaicin promoted endothelium-dependent relaxation in diabetic mice. However, the beneficial effect of capsaicin on vasorelaxation was absent in the aortas of UCP2 ^-/- mice exposed to high-glucose levels.

Conclusion

TRPV1 activation by capsaicin might protect against hyperglycemia-induced endothelial dysfunction through a mechanism involving the PKA/UCP2 pathway.

SU-E-J-22: Effect of MLC Leaf Width on MLC Leaf Shifting Algorithm for Concurrent Treatment of Prostate and Pelvic Lymph Nodes

PURPOSE

Our previous study showed that adjusting selected MLC leaf pairsto follow prostate movement is an effective strategy to account for daily prostate displacement during concurrent treatment with pelvic lymph nodes. MLC leaf width affects the quality of MLC shifting plans for longitudinal prostate motion compensation. This study is to investigate the effect of the MLC leaf width in compensation of the prostate movement.

METHODS

Fifty-one daily CT on-rail scans from three patients were available for this study. On these CTs, the prostate, bladder and rectum were manually contoured, and the lymph nodes contours were transferred from the planning CT after rigid bony registration. For each patient, three different IMRT plans were created based on a planning CT using leaf width of 2.5, 5, and 10 mm, respectively. For each CT, the prostate displacement was determined by dual imaging registration and compensated by shifting MLC resulting in a total of 153 MLC shifted plans.

RESULTS

Among 51 daily CTs, the average prostate movement along the superior/inferior direction was 1.1±3.7 mm (range: -6 to 6.5 mm). The differences in D99 of the prostate between the dose of the day and dose of the plan were 2.3±3.3%, 1.3±2.0%, and 4.4±5.1% for 2.5, 5, and 10 mm leaf width plans, respectively (p<<0.05). The corresponding differences in D99 of the lymph nodes were 0.7±0.9%, 0.6±0.9%, and 1.4±0.8%. The mean differences in D50 were 0.8%, 1.6%, and 2.7% for the bladder, and 10.0%, 3.9%, and 5.7% for the rectum, respectively.

CONCLUSIONS

Using the MLC Shifting method to compensate for prostate movement in the longitudinal direction depends on the MLC leaf width and the magnitude of the prostate motion. The use of leaf width of 5 mm can provide sufficient tumor coverage without significantly affecting doses to the critical structures.

SU-E-J-30: Using Shifting Planned Dose Matrix to Evaluate Daily Dose Changes for IMRT Prostate Treatment

PURPOSE

Summation of daily DVH from KV-cone beam CT (KV-CBCT) to obtain a composite dose volume histogram (DVH) is challenging. Directly translating the planned dose matrix according to measured daily prostate displacements provided a common reference frame for a composite DVH from daily DVHs. The purpose of this study is to evaluate the shifting planned dose matrix method compared to the dose recalculation method using daily KV-CBCT.

METHODS

Six patients, who received concurrent IMRT treatment for prostate and pelvic lymph nodes with 124 daily CBCTs, were selected for this study. Contours for CBCT's were transferred from the planning CT after soft tissue registration for prostate and bony registration for pelvic lymph nodes. Using the same planning beam configurations, we re-calculated doses for these CBCTs after shifting to corrected treatment isocenters. The planned dose matrix translation was performed by an in-house program written in MATLAB and incorporated with Computational Environment for Radiotherapy Research (CERR) software. The corresponding daily DVH was obtained by shifting the planned dose matrix according to shifts of treatment iso-centers. To compare these two methods, selected endpoint doses for tumor targets and sensitive structures were extracted from DVHs.

RESULTS

For prostate displacement less then 1.5 cm, the dose matrix shifting method resulted in 93% and 98% fractions within 5% differences from the recalculation method for D95 of prostate and pelvic lymph nodes, respectively. These numbers decreased to 58% and 71% when 2% dose difference criterion was used.

CONCLUSIONS

Allowing 5% daily dose difference, shifting planned dose matrix provides effective means to evaluating daily dose changes for concurrent IMRT treatment for prostate and pelvic lymph nodes. The utility of this tool is to provide a common coordinate frame to obtain composite dose distributions.

SLICC/ACR damage index independently associated with left ventricular diastolic dysfunction in patients with systemic lupus erythematosus

Left ventricular (LV) diastolic dysfunction has been reported in both active and inactive systemic lupus erythematosus (SLE) patients without clinical evidence of cardiovascular disease. However, the relationship between the long-term inflammatory burden reflected by the SLICC/ACR damage index and LV diastolic function has not been studied. Eighty-two SLE patients and 82 controls matched for age, sex, body mass index, blood pressure and heart rate underwent echocardiography with tissue Doppler imaging (TDI). LV diastolic function was estimated by the myocardial early diastolic velocity (E') at the lateral annulus. There were 51 patients (62.2%) with nephritis, 23 patients (28.0%) with hypertension, 21 patients (25.6%) with vasculitis, 16 patients (19.5%) with pulmonary hypertension, 4 patients (4.9%) with cerebrovascular disease and 2 patients (2.4%) with diabetes mellitus. Sixty-two patients (75.6%) were taking prednisone and 35 patients (42.7%) used a immunosuppressant. Forty-five patients (54.8%) had active disease and suffered from disease-related end-organ damage. Patients with SLICC/ACR damage index ≥1 had more evidence of LV diastolic dysfunction with lower lateral annulus E' (9.6 ± 3.4 vs 12.9 ± 3.5 cm/s, p < 0.001) than those without. In addition, the proportion of patients with abnormal LV myocardial relaxation (defined as lateral E' < 10.0 cm/s) (51.1% vs 16.2%, χ(2) = 10.8, p = 0.001) were significantly higher. Multivariate analysis showed that the SLICC/ACR damage index ≥1 was independently associated with LV diastolic dysfunction (OR = 3.80, 95%CI: 1.21-11.95, p = 0.023) after adjusting for hypertension, disease duration and medical therapy. This may suggest that the overall inflammatory burden in SLE, as reflected by SLICC/ACR damage index, is associated with the development of diastolic dysfunction in SLE patients.

Increased arterial stiffness correlated with disease activity in systemic lupus erythematosus

To evaluate the relationships between arterial stiffness, disease activity and end-organ damage in systemic lupus erythematosus (SLE), non-invasive vascular assessments were made on 32 female SLE patients and 32 female normal controls. The patients had significantly increased brachial-ankle pulse wave velocity (PWV) (13.06 +/- 1.79 vs. 11.50 +/- 1.00 m/s; P < 0.001), heart-ankle PWV (8.98 +/- 1.16 vs. 7.88 +/- 0.73 m/s; P < 0.001), carotid augmentation index (AI) (21.6 +/- 17.2% vs. 5.4 +/- 14.0%; P = 0.001) and carotid intima-medial thickness (IMT) (0.753 +/- 0.132 vs. 0.644 +/- 0.092 mm; P = 0.002) when compared with controls. The disease activity and organ damage were evaluated by SLE disease activity index (SLEDAI) and systemic lupus international collaborating clinics (SLICC) damage index. Patients with active disease (SLEDAI > or = 3) had significantly higher carotid AI (34.4 +/- 9.7% vs. 17.8 +/- 17.3%, P < 0.05) than stable ones (SLEDAI < 3) and those with organ damage (SLICC > or = 1) had significantly higher heart-ankle PWV (9.69 +/- 1.13 vs. 8.61 +/- 1.02 m/s, P < 0.05) than those with SLICC = 0. After making adjustments for age, body mass index (BMI) and blood pressure, carotid AI was found to show correlation with SLEDAI and haPWV with SLICC. A carotid AI value of 33.3% identified SLEDAI > or = 3 with a sensitivity of 83% and a specificity of 80%, whereas a heart-ankle PWV value of 9.0 m/s identified SLICC > or = 1 with a sensitivity of 91% and a specificity of 67%. In conclusion, SLE was an independent risk factor of sub-clinical atherosclerosis and arterial stiffness may identify the presence of active disease.

Quercetin induced tissue-type plasminogen activator expression is mediated through Sp1 and p38 mitogen-activated protein kinase in human endothelial cells

BACKGROUND

Wine polyphenol quercetin upregulates tissue-type plasminogen activator (t-PA) transcription in cultured human umbilical cord vein endothelial cells (HUVECs). However, the regulatory elements and signaling pathways involved in this regulation are unknown.

OBJECTIVES

We aimed to localize quercetin-responsive t-PA promoter elements, identify the proteins that bind these elements, and decipher signaling pathways involved in the regulation of t-PA.

METHODS

To localize quercetin-responsive elements, HUVECs were transiently transfected with various t-PA promoter-reporter constructs. Element functionality was evaluated by mutational analysis. Nuclear protein-t-PA element interactions were evaluated by electrophoretic mobility shift assays (EMSAs) and chromatin immunoprecipitation (ChIP) analysis. Mitogen-activated protein kinase (MAPK) inhibitors were used to determine the signaling pathways involved in t-PA regulation. MAPK inhibition effects were evaluated by real-time PCR, immunoblotting analysis, and transfections. Coimmunoprecipitation was used to evaluate MAPK and transcription factor interaction.

RESULTS

Deletion of the t-PA promoter region - 288 to - 250 resulted in loss of quercetin responsiveness. This region contains putative Sp1-binding elements, which we termed Sp1a and Sp1b. Sp1b mutation abolished the quercetin-inducible response, whereas Sp1a mutation had no effect. EMSA and ChIP analysis demonstrated quercetin-enhanced Sp1 binding to Sp1b. Inhibition of p38 MAPK abrogated basal and quercetin-induced t-PA expression and promoter activity, as well as quercetin-induced Sp1 binding to Sp1b. Quercetin enhanced p38 MAPK and Sp1 physical association, which was similarly diminished by p38 MAPK inhibition.

CONCLUSIONS

We showed, for the first time, the presence of a functional Sp1-binding element in the t-PA promoter controlling quercetin induction via the p38 MAPK pathway. Understanding these mechanisms may provide new insights into polyphenol cardioprotective effects.

[Effects of hepatitis G virus coinfection on hepatic pathological changes of patients with chronic hepatitis B: a long-term comparative study]

OBJECTIVE

To observe the long-term effect of hepatitis G virus (HGV) coinfection on hepatic pathological changes of patients with chronic hepatitis B (CHB) and explore the pathogenicity of HGV.

METHODS

Menghini method liver biopsy was performed on 45 patients with CHB twice with an interval of 5 years on a voluntary basis. The liver tissue of 21 cases was HGV nonstructural region 5 (HGV NS5) antigen positive by peroxidase anti-peroxidase (PAP) immunohistochemical staining assay (HGV coinfection group) in these two tests, and 24 cases were negative (HGV noncoinfection group). There was no significant difference in age, sex, course of disease, amount of serum HBV-DNA by competitive quantitative polymerase chain reaction assay and severity of hepatic pathological leisions between these two groups (P < 0.05) and they were treated with the same scheme and without sustained curative effeect. The hepatic pathological changes of the two groups after 5 years were compared and analysed retrospectively.

RESULTS

There was no significant difference in basic hepatic pathological change, severity of inflammatory activity grade and fibrosis stage in these two groups. The numbers of cases of inflammatory activity grade G1, G2, G3, and G4 were 3, 7, 7, and 4 in HGV coinfection group, and 5, 8, 7, and 4 in HGV noncoinfection group in the beginning of observation; and were 3, 5, 7, and 6 in HGV coinfection group, and 4, 6, 8, and 6 in HGV noncoinfection group after 5 years. The numbers of cases in fibrosis stages S1, S2, S3, and S4 were 4, 7, 7, and 3 in HGV coinfection group, and 6, 8, 6, and 4 HGV noncoinfection group in the beginning of observation; and were 3, 6, 5, 7 in HGV coinfection group, and 4, 7, 5, and 8 in HGV noncoinfection group after 5 years (P > 0.05).

CONCLUSION

HGV coinfection does not lead to the activation of hepatic pathological changes and does not speed up the progression of fibrosis in patients with CHB. HGV coinfection does not play an obvious role in long-term hepatic pathological changes of patients with CHB. HGV has at most a mild hepatic pathogenicity.

Tissue-engineered bone repair of sheep cranial defects with autologous bone marrow stromal cells

Cranial bone defect remains a major challenge to craniofacial surgeons because of limited availability of autologous bone graft to repair the defects and the donor site defects secondary to tissue harvesting. In contrast, tissue-engineering technique can generate a large bone tissue using small amount of autologous cells and therefore avoid these problems. Bone Marrow Stromal Cells (MSCs) have the potential of multi-lineage (including osteogenic) differentiation. The objective of this study was to investigate the potential of using autologous MSCs to repair cranial bone defects by a tissue-engineering approach. Autologous MSCs were isolated from eight adult sheep respectively and were in vitro expanded and induced to become osteogenic cells. Bilateral full-thickness defects (20 mm in diameter) of parietal bones were created in animals and the bone defects were either repaired with the bone implants constituted with MSCs and calcium alginate at the experimental side (n = 8) or treated with calcium alginate only without MSCs (n = 4) or left unrepaired (n = 4) at the control side. New bone tissues were observed either grossly or histologically at the defects of experimental group as early as 6 weeks post-repairing, but not in control groups. The engineered bone tissue became more mature at 18 weeks post-repairing. Three-dimensional computerized tomography (CT) scan revealed an almost complete repair of the defect of experimental group at 18 weeks. This study may provide insight for future clinical repair of cranial defect.

[An experimental study of antisense TGF-beta 1 inhibiting keloid fibroblast proliferation in vitro]

OBJECTIVE

To study the effect of antisense TGF-beta 1 on keloid fibroblast proliferation in vitro.

METHODS

The antisense TGF-beta 1 was transfected into the keloid fibroblast by liposome. The cell count technique was used to test the effect of antisense TGF-beta 1 on keloid fibroblast proliferation in vitro. Cell apoptosis was tested by FCM.

RESULTS

Antisense TGF-beta 1 can inhibit the proliferation of keloid fibroblast in vitro; Antisense TGF-beta 1 can increase the apoptosis ratio of keloid fibroblast in vitro.

CONCLUSIONS

Antisense TGF-beta 1 can induce keloid fibroblast apoptosis and inhibit keloid fibroblast proliferation in vitro, which may contribute to the inhibition of keloid formation in vivo.

[An experimental study of tissue engineered autologous cartilage by using an injectable polymer]

OBJECTIVE

To investigate the proper cell density of tissue engineered autologous cartilage to indicate the clinical application.

METHODS

The chondrocytes, isolated from mini swines' ears, were mixed with an injectable biocompatible matrix(Pluronic F127) to make the cell suspensions with the densities of 10,20, 30,40,50,60,70 x 10(6)/ml. The chondrocyte-polymer complex was injected into the subcutaneous tissue of the swines' abdomens. Each specimen was harvested and evaluated with body-mass, histological examination, and glycosaminoglycan content and type II collagen tests after 6 weeks in vivo.

RESULTS

The histological examination had showed that the neo-cartilage was solid, homogenous cartilage when using 50 million chondrocytess/cc for 6 weeks. The samples with the 10 and 30 million chondrocytes/cc showed that the area of the cartilage was incomplete and separated by the remnant polymer. The mass of the samples was ranged from 30-110 mg after 6 weeks. The glycosaminoglycan content was lower from 5.8 to 9.0 percent, compared to the 9.2 percent of the normal auricular cartilage. Western-Blot had presented the type II collagen in all samples.

CONCLUSION

This study has demonstrated that the qutologous cartilage could be generated by using tissue engineering technique, with the histological characteristics similar to natural cartilage. Fifty million chondrocytes per cc could yield the best quality cartilage in 6 weeks.

[Expression of hepatitis B virus antigen in brain tissue from liver cirrhosis patients with hepatitis B and its significance]

OBJECTIVE

To investigate the expression of hepatitis B virus (HBV) antigen in brain tissue from liver cirrhosis patients with hepatitis B and explore its significance.

METHODS

HBsAg and HBcAg were detected in the brain tissue from 70 liver cirrhosis dead patients with hepatitis B by S-P immunohistochemical assay, and the relationship between the expression of HBV antigen in brain tissue testing and clinic and pathology was analyzed.

RESULTS

30 patients (42.89%) were positive for HBV antigen. Among them, 24 patients (34.29%) were positive for HBsAg and 18 patients (25.71%) were positive for HBcAg. HBV antigen was mainly found in cytoplasm and distributed in neurons, neurogliocytes and vascular endothelial cells. The positive cells were distributed separately, scatteredly or focally. The expression of HBV antigen was not associated with the serum level of HBV replication but associated with the occurrence of hepatic encephalopathy (HE) and the severity of brain tissue pathologic lesions of HE.

CONCLUSIONS

The results indicate that HBV infection develop in brain tissue from liver cirrhosis patients with hepatitis B and HBV may replicate in it. HBV infection in brain tissue may p lay an important role in occurrence and development of HE from liver cirrhosis patients with hepatitis B.

In-vitro cultivation of normal human oral keratinocytes

OBJECTIVE

To establish a method for culturing normal human oral keratinocytes.

METHODS

Specimens obtained from healthy humans undergoing oral surgery were dissociated into single cell suspensions by dispase and trypsin. The cells were grown in serum-free medium. Morphological characteristics were studied under light microscope and electron microscope. Cytokeratins were shown by immunohistochemistry.

RESULTS

Cells could be maintained in culture up to 4-5 passages or 30-50 days. Electron microscope revealed that there were desmosomes and tonofibrils in the oral keratinocytes. The cells showed positive staining for cytokeratin antibody.

CONCLUSION

Human oral keratinocytes have been successfully grown in serial culture.

[Reconstruction of corneal stroma using tissue engineering technique]

OBJECTIVE

To reconstruct new corneal stroma in order to provide a basis for future studies on the reconstruction of cornea.

METHODS

The cultured corneal stromal cell-PGA complex was grafted to the subdermis of a female balb/c nude mouse. Six weeks after grafting, the new reformed tissue was fixed for histologic examination and transmission electron microscopy (TEM). At the same time, the new deposited collagen fibril diameter was measured.

RESULTS

The reconstructed corneal stromal layer was formed in a waved, crossed-web structure, which was similar to the normal corneal stroma. Cell deposited collagen fibrils were similar in diameter to those seen in normal corneal stroma.

CONCLUSIONS

The corneal stroma can be reconstructed by using tissue engineering technique. The reconstructed tissue which is similar to the normal cornea in key characteristics, including morphology and histologic structure provides an ideal experimental model for corneal physiological, pathologic, toxic and drug efficient testing and for future development of the tissue for implantation.

Differential expression of CCAAT/enhancer-binding protein-delta (c/EBPdelta) in rat androgen-dependent tissues and human prostate cancer

CCAAT/enhancer-binding protein delta (C/EBPdelta) is a nuclear transcription factor that regulates cellular growth and differentiation. In this study we demonstrate that C/EBPdelta gene expression is differentially regulated in rat androgen-dependent tissues and human prostate cancer. C/EBPdelta messenger RNA (mRNA) levels were very low in adult rat ventral prostate, epididymis, and testis. In ventral prostate and epididymis, expression of C/EBPdelta mRNA increased more than sixfold when testicular testosterone was eliminated by surgical castration or treatment with ethane-1,2-dimethanesulfonate (EDS). Testosterone replacement reduced C/EBPdelta mRNA levels to near control values in both tissues. CWR22 is a human prostate cancer xenograft that mimics biological characteristics of androgen-dependent and androgen-independent human prostate cancer. In androgen-dependent CWR22 tumors, expression of C/EBPdelta mRNA declined in response to castration. Both C/EBPdelta mRNA and protein levels increased following testosterone administration. However, C/EBPdelta mRNA and protein levels were variable in recurrent CWR22 tumors growing in the absence of testicular androgen for approximately 5 months. C/EBPdelta expression was also variable in androgen-independent human prostate carcinomas (n = 3), although mRNA levels were substantially lower than those in androgen-dependent tumors (n = 3). These studies demonstrate that androgen down-regulates C/EBPdelta levels in androgen-dependent rat tissues, but induces C/EBPdelta expression in androgen-dependent human prostate cancer. Deregulation of C/EBPdelta occurs when prostate cancer progresses to the androgen-independent state.

An antimicrobial peptide gene found in the male reproductive system of rats

Little is known about the innate defense mechanisms of the male reproductive tract. We cloned a 385-base pair complementary DNA and its genomic DNA named Bin1b that is exclusively expressed in the caput region of the rat epididymis and that is responsible for sperm maturation, storage, and protection. Bin1b exhibits structural characteristics and antimicrobial activity similar to that of cationic antimicrobial peptides, beta-defensins. Bin1b is maximally expressed when the rats are sexually mature and can be up-regulated by inflammation. Bin1b appears to be a natural epididymis-specific antimicrobial peptide that plays a role in reproductive tract host defense and male fertility.

[Disinfection for cistern water]

Rainwater is often collected into cisterns (pits or tanks) for household using as drinking water source in the rural areas of the northwest and the southeast coast in China, where no enough fresh water resource is available. However, the total number of bacteria and coliforms in the cisterns water was higher than the standard of that in drinking water. In order to ensure the safety for drinking, the effectiveness, conditions of treatment and cost for such disinfection methods compared with solar radiation, ultraviolet (UV), chloridation, micro-filteration and KDF were studied in 10 households in Cixi of Zhejiang Province and Weiyuan of Gansu Provinces, respectively. The micro-filteration is more compatible for bacteria removal in the tanks, while chloridation more for disinfection in the underground pits.

[Serial cultivation of normal human oral keratinocytes]

OBJECTIVE

To establish a method of culturing normal human oral keratinocytes.

METHODS

Specimens obtained from healthy humans undergoing oral surgery were dissociated by Dispase and trypsin into a single cell suspension. The cells were grown in serum-free medium. Morphological characteristics were studied under light microscope and electron microscope (EM). Cytokeratins were showed by immunohistochemistry.

RESULTS

The cells could be maintained in culture up to 4-5 passages, or 30-50 days. EM revealed that there were desmosomes and tonofibrils in the culture cells. The cells showed positive staining for cytokeratin antibody.

CONCLUSIONS

The culture technique for growing normal human oral keratinocytes has been established.

[An initial experiment study on allogenic tissue engineered cartilage]

OBJECTIVE

To investigate the formation of engineered cartilage in vivo with allogenic chondrocytes.

METHODS AND MATERIALS

Joint cartilage from ewe embryos (Pregnancy: 100 days) was isolated and digested to obtain dissociated chondrocytes. Mixed chondrocytes with biomaterials (Pluronic 127) at the density 50 x 10(6)/ml, then implant the allograft complex subcutaneously. Collect the novel tissue every two weeks along for six months, weigh and stain (HE, Safranin O, Masson's trichrome) the sample tissues individually to evaluate the characteristics of novel tissue.

RESULT

Novel cartilage can regenerate in allograft animals, with similar histological properties of chondrocytes, aminoglycin and collagen distribution to normal cartilage. The novel cartilage observed histologically showed apparent surrounding inflammatory cells in two and four week and the tissue of cartilage came to mature since the sixth week, with less inflammatory reaction, but not disappeared.

CONCLUSION

Novel cartilage can generate in allograft animals with tissue engineering approach, with certain immunoreaction surrounding. Such reaction will be weakened gradually with time.

[The effects of hepatitis G virus infection on clinical features and liver pathologic lesions of chronic hepatitis C]

OBJECTIVE

To explore the clinical and pathological effect of hepatitis G virus infection on chronic hepatitis C.

METHODS

Detecting HGV-RNA by reverse transcription-polymerase chain reaction from serum samples of 53 chronic hepatitis C through patients as diagnosed by liver biopsy. The clinical and pathologic features of the patients with positive HGV-RNA were compared with those of patients with negative HGV-RNA.

RESULTS

The results showed that 15 patients (28.3%) were positive for serum HGV-RNA and there were no significant differences in clinical manifestations, biochemical indexes, HCV-RNA positive rates and the liver pathologic lesions between these HGY RNA positive and negative groups (P > 0.05).

CONCLUSIONS

These data indicate that HGV coinfection does not affect the liver lesions and HCV replication of chronic hepatitis C.

[Repairing peripheral nerve defects by tissue engineering techniques:an experimental study]

OBJECTIVE

To develop a novel effective substitute material or technique to repair peripheral nerve gap.

METHODS

We inoculated expanded Schwann cells (SCs) at re-arranged bio-absorbable polymer polyglycolic acid (PGA) fiber and incubated for two weeks, then we developed a novel tissue-engineered scaffolds. The scaffolds were used as cellular isografts to bridge 15 mm long gap of sciatic nerve in inbred strains of Wistar rats. In an autologous and pure PGA fiber control group, the same surgical procedure was used. Evaluation included general observation, electromyographic examination, muscle measurement, and histological observation of serial sections at 12 weeks after surgery. The total number and density of reinnervation and thickness of myelin sheath was measured by computerized image analysis.

RESULTS

SCs put out a long and thin prominence and migrated along the PGA fibers in spirality or parallel when they divided and finally rank into a cell-chain formation similar to Büngner's band. TEM/SEM and immunohistochemical survey demonstrated that the SCs at PGA fiber also secreted a great deal of ECMs included laminin, which play a very important role in peripheral nerve regeneration. Non-tubular scaffold comprised SCs and laminin (LN) channel in three-dimensional longitudinal rank. Animal transplantation study indicated the sensory and motor functional results of hindlimbs of experimental group rats reached to similar level of those found in nerve autograft control group. The number of reinnervation in the experimental group rats was slightly fewer than that in nerve autograft control group; but the axonal density was just reversal between the two groups because of a large area ischemic necrosis in the center of nerve autografts.

CONCLUSION

This new paradigm offers a potential solution to repairing a long gap of peripheral nerve.

[A fitting power curve equation for the accumulative inhaling volume in Chinese under 19 years old]

A fitting power curve equation based on the breath frequency and body weight for the accumulative inhaling volume in Chinese under 19 years old was established. The equation is Y = 754.37 + 258.34 X1.9038, and the fitting is good (R2 = 0.9974). It is useful for estimating the degree of exposure to air pollutants of people in their young period.