Exploring the Deoxy-D-xylulose-5-phosphate Synthase Gene Family in Tomato (Solanum lycopersicum)

Isoprenoids are a wide family of metabolites including high-value chemicals, flavors, pigments, and drugs. Isoprenoids are particularly abundant and diverse in plants. The methyl-D-erythritol 4-phosphate (MEP) pathway produces the universal isoprenoid precursors isopentenyl diphosphate and dimethylallyl diphosphate in plant plastids for the downstream production of monoterpenes, diterpenes, and photosynthesis-related isoprenoids such as carotenoids, chlorophylls, tocopherols, phylloquinone, and plastoquinone. The enzyme deoxy-D-xylulose 5-phosphate synthase (DXS) is the first and main rate-determining enzyme of the MEP pathway. In tomato (Solanum lycopersicum), a plant with an active isoprenoid metabolism in several tissues, three genes encode DXS-like proteins (SlDXS1 to 3). Here, we show that the expression patterns of the three genes suggest distinct physiological roles without excluding that they might function together in some tissues. We also confirm that SlDXS1 and 2 are true DXS enzymes, whereas SlDXS3 lacks DXS activity. We further show that SlDXS1 and 2 co-localize in plastidial speckles and that they can be immunoprecipitated together, suggesting that they might form heterodimers in vivo in at least some tissues. These results provide novel insights for the biotechnological use of DXS isoforms in metabolic engineering strategies to up-regulate the MEP pathway flux.

MEP pathway products allosterically promote monomerization of deoxy-D-xylulose-5-phosphate synthase to feedback-regulate their supply

Isoprenoids are a very large and diverse family of metabolites required by all living organisms. All isoprenoids derive from the double-bond isomers isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP), which are produced by the methylerythritol 4-phosphate (MEP) pathway in bacteria and plant plastids. It has been reported that IPP and DMAPP feedback-regulate the activity of deoxyxylulose 5-phosphate synthase (DXS), a dimeric enzyme that catalyzes the main flux-controlling step of the MEP pathway. Here we provide experimental insights into the underlying mechanism. Isothermal titration calorimetry and dynamic light scattering approaches showed that IPP and DMAPP can allosterically bind to DXS in vitro, causing a size shift. In silico ligand binding site analysis and docking calculations identified a potential allosteric site in the contact region between the two monomers of the active DXS dimer. Modulation of IPP and DMAPP contents in vivo followed by immunoblot analyses confirmed that high IPP/DMAPP levels resulted in monomerization and eventual aggregation of the enzyme in bacterial and plant cells. Loss of the enzymatically active dimeric conformation allows a fast and reversible reduction of DXS activity in response to a sudden increase or decrease in IPP/DMAPP supply, whereas aggregation and subsequent removal of monomers that would otherwise be available for dimerization appears to be a more drastic response in the case of persistent IPP/DMAPP overabundance (e.g., by a blockage in their conversion to downstream isoprenoids). Our results represent an important step toward understanding the regulation of the MEP pathway and rational design of biotechnological endeavors aimed at increasing isoprenoid contents in microbial and plant systems.

[Treatment strategies and research progress of acute ilio-femoral deep vein thrombosis]

In the past,treatment of acute ilio-femoral deep vein thrombosis (IFDVT) was mainly based on anticoagulation alone,but 30%-50% of patients will develop post-thrombotic syndrome,causing a serious medical burden.Thrombus removal technology such as catheter-directed thrombolysis and percutaneous mechanical thrombectomy can effectively remove blood clots and compensate for the deficiencies of simple anticoagulation,which is expected to improve the prognosis of such disease,but the current evidence is insufficient,and other treatments such as filter implantation and compression therapy are also controversial.This article summarizes the treatment strategies and the latest progress of acute IFDVT,hoping to help the treatment of this type of disease.

A comparison between raltitrexed plus cisplatin and docetaxel plus cisplatin in concurrent chemoradiation for non-surgical esophageal squamous cell carcinoma

PURPOSE

Chemoradiotherapy (CRT) is considered as a standard treatment for unresectable and inoperable esophageal cancer (EC) patients. However, no consensus has been reached regarding the optimal synchronous chemotherapy regimen and the best combination of radiotherapy and chemotherapy. The aim of this study was to evaluate the efficacy and toxicity of raltitrexed plus cisplatin and docetaxel plus cisplatin to find a safe and effective concurrent chemotherapy schedule.

PATIENTS AND METHODS

Our retrospective study included 151 EC patients treated with raltitrexed and cisplatin (RP) (n=90) or docetaxel and cisplatin (DP) (n=61) from 2011 till 2018. Survival outcomes and treatment related toxicity were analyzed between the two groups.

RESULTS

PFS and OS were 18 and 34 months in the RP group, while 13 and 20 months in the DP group (P=0.118 and P=0.270). The 1-, 2-, 3-year survival rates of the RP group were 71.1, 55.4 and 46.4%. For the DP group, these were 63.9, 44.3 and 37.6%, respectively. Compared with DP group, RP group received a superior CR rate (68.9% versus 52.5%, P=0.041). There was a trend that the total number of toxic reactions in RP group was lower than that in DP group (P=0.058).

CONCLUSIONS

Even RP and DP groups have the similar survival outcomes and toxicity, raltitrexed/cisplatin get a higher complete response rate. Our study suggests that raltitrexed combined with cisplatin is a safe and effective concurrent chemotherapy regimen and it might be used as an alternative for cisplatin/5-FU and cisplatin/docetaxel in CCRT for EC patients.

AB0126 EXPRESSION CHARACTERISTICS OF ADENOSINE DEAMINASES ACTING ON RNA-1 IN SYSTEMIC LUPUS ERYTHEMATOSUS AND ITS CORRELATION WITH SERUM IFN-Α

Background:

SLE is a multisystem autoimmune disease characterized by the production of multiple autoantibodies and loss of immunity against autoantigens in various tissues. SLE patients have significantly elevated RNA editing levels and the potential to produce new autoantigens.1ADAR1 is an RNA A-I editing enzyme that converts adenine to hypoxanthine and contributes to SLE pathogenesis.2

Objectives:

Dama demonstrated the upregulation of ADAR1p150 expression in SLE T cells, B cells, PBMCs, and NK cells;3however, the following issues were not reported in detail: 1. specific alterations in ADAR1 expression in PBMCs collected from SLE patients with varying degrees of the disease and its correlation with serum IFN-α levels; 2. association between ADAR1 and clinical indicators; and 3. ADAR1 expression in renal tissue of LN patients. Our study therefore aimed to elucidate the abovementioned points.

Methods:

We used qRT-PCR to determine ADAR1 expression levels in PBMCs and renal tissues of controls and SLE patients. We also conducted immunohistochemical studies to detect positive ADAR1 expression rate in renal cells of controls and LN patients.

Results:

ADAR1 expression was higher in PBMCs of SLE patients than in those of controls and was positively correlated with SLEDAI. When serum IFN-α levels in SLE patients decreased <260.0 pg/mL, ADAR1 expression in PBMCs increased with the increase in IFN-α concentration, and serum IFN-α may regulate ADAR1 level in PBMC in SLE patients, which may require the participation of serum IgG antibody and related immune complex. However, there was no significant difference between the expression in renal tissues in all patients.

Conclusion:

There was a certain correlation between ADAR1 expression and serum IFN-α levels in PBMCs of SLE patients.

References:

[1]Roth SH, Danan-Gotthold M, Ben-Izhak M, et al. Increased RNA Editing May Provide a Source for Autoantigens in Systemic Lupus Erythematosus.Cell Rep2018; 23: 50-57.

[2]Hogg M, Paro S, Keegan LP and O’Connell MA. RNA editing by mammalian ADARs.Adv Genet2011; 73: 87-120.

[3]Laxminarayana D, Khan IU, O’Rourke KS and Giri B. Induction of 150-kDa adenosine deaminase that acts on RNA (ADAR)-1 gene expression in normal T lymphocytes by anti-CD3-epsilon and anti-CD28.Immunology2007; 122: 623-633.

Figure 1.

Analysis of ADAR1 expression levels. a. The ADAR1 expression in PBMCs was higher in SLE patients (n=30) than in healthy controls (n = 30) (p<0.05). b. SLE patients were divided into three groups: NSLE (SLEDAI 0–4, n = 6), LSLE (SLEDAI 5–9, n = 12), and SSLE (SLEDAI ≥10, n = 12) according to SLEDAI score. c. Based on the effect of the disease on the kidneys, the patients were divided into the SLE#group (#:SLE patient group without the kidney involved, n = 17) and LN group (lupus nephritis group, n = 13). d. There was no significant difference observed between the renal tissues of controls (n = 5) and LN patients (n = 10) (p>0.05).

Figure 2.

a. Immunohistochemical image of renal tissues from the two groups (200×). b. There was no significant difference in the ADAR1 cell positive rate between controls (n = 5), LN patients(n = 20), and different pathological subgroups (class III, n = 5; class IV, n = 5; class V, n = 5; class III+IV, n = 5) (p>0.05). c. The positive expression rate of ADAR1 in renal tubular cells was higher than that in glomerular cells both in the two groups (p<0.05).

Figure 3.

a. Correlation between ADAR1 and serum IFN-α levels in PBMCs of SLE patients. b. Correlation between ADAR1p150 and serum IFN-α levels in PBMCs of SLE patients.

Figure 4.

In vitroPBMCs assay. a. Western blot (WB) analysis of ADAR1p150 and ADAR1p110 in PBMCs using different concentrations of IFN-α, combined with 1.5 mg/mL IgG purified from the serum of SLE patients or without it, and cultured for 24 hours. b. The line graph depicts the trend of ADAR1, ADAR1p150, and ADAR1p110 expression with increase in IFN-α concentrationin vitroPBMCs co-cultured with serum IgG from SLE patients.

Disclosure of Interests:

None declared

THU0243 HSA_CIRC_0123190 FUNCTIONS AS A COMPETITIVE ENDOGENOUS RNA TO REGULATE APLNR EXPRESSION BY SPONGING HSA-MIR-483-3P IN LUPUS NEPHRITIS

Background:

Lupus nephritis (LN) is one of the most severe complications of systemic lupus erythematosus (SLE). Circular RNAs(circRNAs) can act as competitive endogenous RNAs (ceRNAs) to regulate gene transcription, which is involved in mechanism of many diseases, such as, autoimmunity diseases. However, the role of circRNA in lupus nephritis has been rarely reported.

Objectives:

In this study, we aim to investigate the clinical value of circRNAs and explore the mechanism of circRNA involvement in the pathogenesis of LN.

Methods:

Renal tissues from three untreated LN patients and three normal controls (NCs) were used to identify differently expressed circRNAs by RNA sequencing (RNA-seq). Validated assays were used by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Correlation analysis and receiver operating characteristic (ROC) curve were used to reveal the clinical value of selected circRNA, miRNA and mRNA. The interactions between circRNA and miRNA, or miRNA and mRNA were further determined by luciferase reporter assay. The degrees of renal fibrosis between the two groups were compared by Masson-trichome staining and immunohistochemistry staining.

Results:

159 circRNAs were significantly dysregulated in LN patients compared with NC group. The expression of hsa_circ_0123190 was significantly decreased in renal tissues of patients with LN (p=0.014), as same as the sequencing results. The area under the ROC curve of hsa_circ_0123190 in renal tissues was 0.820. Bio-informatic analysis and luciferase reporter assay illustrated that hsa_circ_0123190 can act as a sponge for hsa-miR-483-3p which was also validated to interact with APLNR mRNA. APLNR mRNA expression was positively related with chronicity index (CI) of LN (R2=0.452,p=0.033). Finally, the factors of renal fibrosis, especially TGF-β (p=0.018), were more pronounced in the LN group.

Conclusion:

Hsa_circ_0123190 could function as a ceRNA to regulate APLNR expression involved in renal fibrosis by sponging hsa-miR-483-3p in LN

References:

[1]Aljaberi N, Bennett M, Brunner HI, Devarajan P. Proteomic profiling of urine: implications for lupus nephritis. Expert review of proteomics. 2019;16(4):303-13.

[2]Zheng ZH, Zhang LJ, Liu WX, Lei YS, Xing GL, Zhang JJ, et al. Predictors of survival in Chinese patients with lupus nephritis. Lupus. 2012;21(10):1049-56.

[3]Chen LL. The biogenesis and emerging roles of circular RNAs. Nature reviews Molecular cell biology. 2016;17(4):205-11.

[4]Mahmoudi E, Cairns MJ. Circular RNAs are temporospatially regulated throughout development and ageing in the rat. Scientific reports. 2019;9(1):2564.

[5]Liang D, Wilusz JE. Short intronic repeat sequences facilitate circular RNA production. Genes & development. 2014;28(20):2233-47.

[6]Tan WL, Lim BT, Anene-Nzelu CG, Ackers-Johnson M, Dashi A, See K, et al. A landscape of circular RNA expression in the human heart. Cardiovascular research. 2017;113(3):298-309.

[7]Zhao Z, Li X, Jian D, Hao P, Rao L, Li M. Hsa_circ_0054633 in peripheral blood can be used as a diagnostic biomarker of pre-diabetes and type 2 diabetes mellitus. Acta diabetologica. 2017;54(3):237-45.

[8]Ouyang Q, Huang Q, Jiang Z, Zhao J, Shi GP, Yang M. Using plasma circRNA_002453 as a novel biomarker in the diagnosis of lupus nephritis. Molecular immunology. 2018;101(undefined):531-8.

[9]Luan J, Jiao C, Kong W, Fu J, Qu W, Chen Y, et al. CircHLA-C Plays an Important Role in Lupus Nephritis by Sponging miR-150. Molecular therapy Nucleic acids. 2018;10(undefined):245-53.

[10]Kuschnerus K, Straessler ET, Müller MF, Lüscher TF, Landmesser U, Kränkel N. Increased Expression of miR-483-3p Impairs the Vascular Response to Injury in Type 2 Diabetes. Diabetes. 2019;68(2):349-60.

[11]Huang Z, Wu L and Chen L. Apelin/APJ system: A novel potential therapy target for kidney disease. Journal of cellular physiology. 2018;233(5): 3892-900.

Disclosure of Interests:

None declared

The role of let-7 and HMGA2 in the occurrence and development of lung cancer: a systematic review and meta-analysis

OBJECTIVE

To evaluate the prognostic role of microRNA let-7 in lung cancer and the relationship between the expression of HMGA2 and clinical significance of lung cancer by meta-analysis.

MATERIALS AND METHODS

The studies on the correlation between the low expression of let-7 and the prognosis of lung cancer, and between the expression of HMGA2 and the occurrence and development of NSCLC were identified by searching PubMed, Web of the Science, Medline, Cochrane Library, Google Scholar, CNKI, CBM, and VIP databases. The StataSE12.0 software was used for meta-analysis.

RESULTS

A total of 10 studies correlating the low expression of let-7 with the lung cancer prognosis were analyzed. The results suggest that the low expression of let-7 indicates a poor overall survival rate, with a hazard ratio value of 1.55 (95%CI:1.16-2.09, p<0.05). Furthermore, nine case-control studies of HMGA2 expression in NSCLC tissues were evaluated. The results showed that the expression of HMGA2 in lung cancer is significantly higher than in normal paraneoplastic tissues. High expression of HMAG2 has been observed in patients with late TNM stages and lymph node metastasis.

CONCLUSIONS

Low expression of let-7 is closely related to the poor prognosis of lung cancer patients. The higher expression of HMGA2 in lung tissues correlates positively with the occurrence and invasiveness of lung cancer. Among malignant tumors, lung cancer is the leading cause of mortality. Early diagnosis and accurate prognosis are the keys to improving the survival rate of patients with this disease.

[Risk factors for long-term result of endovascular treatment for auto-immune disease related abdominal aorta pseudo-aneurysm]

Objective: To summarize results of endovascular treatment for auto-immune disease related abdominal aorta pseudo-aneurysm(AIPA), and to analysis clinical predictors of long term major adverse clinical events(MACE). Methods: Retrospectively collected endovascular treatment for AIPA cases in Peking Union Medical College Hospital within 2000 to 2015. Twenty-nine cases with AIPA treated by endovascular therapy were enrolled in this study. Twenty five cases were male, range from 23 to 67 years old, mean age was (39.3±11.4) years old.Demographic characters, locations of aneurysms, type to auto-immune disease, immuno medical therapy, operation strategy and long term follow-up data were reported. Statistical analysis was made to verify clinical predictors of long-term MACE. Results: Among the 29 cases, 22 cases with bechet's disease, 4 cases with Takayasu's arteritis, 2 cases with systemic lupus erythematosus, 1 cases with polyarteritis nodosa. Eight cases had ruptured or pending ruptured pesudo-aneurysms, the rest 21 cases had dull pain or no overt symptome. Twenty-four cases had infra-renal artery aneurysms, two were para-and supra-renal artery, two were supra-celiac artery, and the rest one had multiple aneurysms involved thoracic and abdominal aorta.All the cases received regular immune medical therapy except the three emergency cases. All the operations were under general anaesthesia. Nineteen cases underwent classical Endovascular aortic aneurysm repair (EVAR), 5 cases underwent fenestration EVAR, the rest 5 cases underwent hybrid procedure. All the 29 operations were successful, without conversion to open surgery. Major peri-operation complication included 3 incision infection, 3 pulmonary infection. No death occurred. All the cases received regular follow-up from 1 to 120 months. There were five recurrence of pseudo-aneurysm, 1 case suffered from iliac limb occlusion. 5 cases received re-intervention procedure. No occlusion of revascularizal visceral artery was found during follow-up. There were 3 deaths during follow-up, with 1 aneurysm related death, the rest died due to other reasons. Single factors logical regressions analysis showed discontinuing immune medicine therapy and age no less than 40 years significantly related long-term MACE(P<0.05). Meanwhile, type of original auto-immune disease, none classical EVAR were not significant related to MACE. Conclusions: Endovascular therapy is safe and effective for AIPA. Regular peri-operation and long-term immunotherapy is key to success.

[Effectiveness of unilateral selective laser trabeculoplasty for primary open angle glaucoma]

OBJECTIVE

To study the effectiveness of unilateral selective laser trabeculoplasty (SLT) on the both eyes of patients with primary open-angle glaucoma (POAG).

METHODS

This was a self-controlled clinical study. Thirty-two patients of 32 eyes with OAG who used same anti-glaucoma medications for both eyes were included aat the Department of Ophthalmology Peking University third Hospital from February 2010 to April 2014. SLT was performed for the poorly controlled eye for each patient. Patients were examined before operation and 1 hour, 1 week, 1 month, 3 months and 6 months after operation. The intraocular pressure was examined after 1 hour of SLT. The rest time points were examined by visual acuity, intraocular pressure (IOP), slit lamp microscope, fundus ophthalmoscope and visual field. The paired t test (Bonferroni) was used to compare the IOP at each time point after SLT with the baseline IOP before SLT. Single factor analysis of variance was used to compare the percentage of IOP drop. Linear correlation analysis was used to analyze the amplitude of the decrease of IOP between treated eyes and untreated eyes at 6-month post-operatively and analyze the IOP between preoperative eyes and 6-month post-operative eyes. The magnitude of the decrease of IOP in patients with glaucoma medication and 6 months after surgery was analyzed. We also analyzed the types of antiglaucoma medications and IOP reductions range for 6 month after SLT.

RESULTS

The preoperative mean IOP was (18.9±2.5) mmHg (1 mmHg=0.133 kPa) in the treated eye of patients with OAG. Mean IOP reduction for 1 week, 1, 3, and 6 months after SLT were (1.7±2.9) mmHg, (2.5±2.5) mmHg, (3.5±2.8) mmHg, (3.4±2.5) mmHg and the percentage of IOP reduction were (8±16) %, (13±13) % (18±14) %, (18±12) % respectively (compared with the baseline, P< 0.05) . With the success criteria of IOP reduction ≥3.0 mmHg or ≥20%, the success rate of SLT in the treated eye after 1 week, 1, 3, 6 months was 38%, 52%, 50% and 60% respectively. For the untreated fellow eyes, the preoperative mean IOP was (17.3±2.4) mmHg. Mean IOP reduction for 1 week, 1month, 3 month, and 6 month after SLT were (1.1±2.0) mmHg, (1.0±2.7) mmHg, (2.6±2.2) mmHg and (2.5±2.2) mmHg respectively (compared with the baseline, P<0.05) . There was a positive correlation between preoperative IOP and IOP reduction either in the treated or in the untreated eyes at 6-month post-SLT (R=0.63, P<0.01; R=0.60, P<0.01) . There was a positive correlation in IOP reduction between treated eyes and untreated eyes at 6-month post-operative (R=0.66, P<0.01). All patients didn't need further treatment such as another laser treatment or surgery. Anti-glaucoma medications were remained unchanged after SLT.

CONCLUSIONS

In poorly anti-glaucoma medication controlled Chinese POAG eyes with mean IOP about 18.0 mmHg, unilateral STL can reduce the IOP about 18% at 6-month post-operative for the treated eyes. There was also a continuous IOP reduction effects for the fellow eyes.(Chin J Ophthalmol, 2016, 52: 410-415).

Effect of CYP2C9*3 mutant variants on meloxicam pharmacokinetics in a healthy Chinese population

The aim of this study was to investigate the effect of the CYP2C9*3 (CYP2C9 1075 A>C) polymorphism on meloxicam pharmacokinetics in a Chinese population. Twenty-four healthy volunteers were enrolled in this study. The pyrosequencing technique was used to identify polymorphisms of CYP2C9. The concentration of meloxicam in plasma was determined by a high-performance liquid chromatography assay with mass spectrographic analysis. The Drug and Statistics Software (DAS, version 2.0) was used for curve fitting and calculations of pharmacokinetic parameters. The effects of CYP2C9*3 variant genotypes on meloxicam pharmacokinetics were compared with those of the wild type genotype. Among the 24 volunteers, two AC heterozygotes were observed in the multi-dose group. CYP2C9*3 was found to play an important role in the metabolism of meloxicam by reducing its enzymatic activity. Therefore, results of this study provide helpful information regarding inter-individual pharmacokinetic variability in the Chinese population.

FDG-PET/CT imaging for staging and definition of tumor volumes in radiation treatment planning in non-small cell lung cancer

7574

Background: 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) /computed tomography (CT) has a potential improvement for staging and radiation treatment (RT) planning of various tumor sites. But from a clinical standpoint, the open questions are essentially the following: to what extent does PET/CT change the target volume? Can PET/CT reduce inter-observer variability in target volume delineation? We analyzed the use of FDG-PET/ CT images for staging and evaluated the impact of FDG- PET/CT on the radiotherapy volume delineation compared with CT in patients with non-small cell lung cancer (NSCLC) candidates for radiotherapy. Intraobserver variation in delineating tumor volumes was also observed. Methods: Twenty-three patients with stage I-III NSCLC were enrolled in this pilot study and were treated with fractionated RT based therapy with or without chemotherapy. FDG-PET/CT scans were acquired within 2 weeks prior to RT. PET and CT data sets were sent to the treatment planning system Pinnacle through compact disc. The CT and PET images were subsequently fused by means of a dedicated radiation treatment planning system. Gross Tumor Volume (GTV) was contoured by four radiation oncologists respectively on CT (CT-GTV) and PET/CT images (PET/CT-GTV). The resulting volumes were analyzed and compared. Results: For the first phase, two radiation oncologists outlined together the contours achieving a final consensus. Based on PET/CT, changes in TNM categories occurred in 8/23 cases (35%). Radiation targeting with fused FDG-PET and CT images resulted in alterations in radiation therapy planning in 12/20 patients (60%) by comparison with CT targeting. The most prominent changes in GTV have been observed in cases with atelectasis. For the second phase was four intraobserver variation in delineating tumor volumes. The mean ratio of largest to smallest CT-based GTV was 2.31 (range 1.01–5.96). The addition of the PET data reduced the mean ratio to 1.46 (range 1.12–2.27). Conclusions: PET/CT fusion images could have a potential impact on both tumor staging and treatment planning. Implementing matched PET/CT reduced observer variation in delineating tumor volumes significantly with respect to CT only.

[Table: see text]

Endoscopic endonasal surgery for biopsy of cavernous sinus lesions

INTRODUCTION

The etiology of cavernous sinus (CS) lesions remains difficult to determine due to the wide range of pathological processes and in spite of the development of neuroimaging techniques. Microsurgery is still not appropriate to take a biopsy of CS lesions for diagnostic purposes while biopsy was rarely attempted by fine-needle aspiration guided by computed tomography. The authors present a new application to endoscopic endonasal surgery for the biopsy of lesions arising from or invading the cavernous sinus.

METHODS

Ten patients diagnosed with cavernous sinus lesions, 5 male and 5 female, whose ages ranged from 20 to 58 years (mean+/-SD: 38.4+/-11.8 years) underwent an endoscopic biopsy via the endonasal transphenoid approach by using 0 degrees and 30 degrees lens endoscopes. Nine of the 10 patients experienced headache, 6 presented with visual disturbances, and 2 presented with a decrease in facial sensation. Preoperative MRI identified 6 patients with CS lesions on right side, 3 on the left and 1 on both sides.

RESULTS

The accuracy of the diagnosis with this technique was 100%. The pathological diagnosis of the cavernous sinus lesions showed 3 patients with nasopharyngeal carcinoma, 2 patients with meningioma, 1 patient with esthesioneuroblastoma, 1 giant cell tumor of bone, 1 small cell carcinoma from the lungs, 1 fungal granuloma, and 1 schwannoma. Postoperatively 6 patients received radiotherapy, 1 patient received antifungal treatment, and the others did not receive any treatment, but were followed up in the clinic. The course of one patient was complicated by an internal carotid artery injury which was treated by interventional balloon occlusion, and another with transient cerebrospinal leakage cured within a week by subarachnoid drainage.

CONCLUSION

The authors present an alternative surgical approach for the diagnostic biopsy of CS under a direct endoscopic visualization. The technique is safe, effective and accurate for biopsy and provides a surgical route that can be added to the armamentarium for the management for pathological conditions in this region.

A low concentration of genistein induces estrogen receptor-alpha and insulin-like growth factor-I receptor interactions and proliferation in uterine leiomyoma cells

BACKGROUND

Previously, we found that genistein at low concentrations stimulates the growth of human uterine leiomyoma (LM) cells, but not uterine smooth muscle (myometrial) cells (SMC). The aim of this study was to understand the molecular mechanism whereby genistein causes hyperproliferation of LM cells.

METHODS

The effects of genistein at 1 microg/ml on LM cells and SMC were evaluated using estrogen response element gene reporter, real-time RT-PCR, western blot, immunoprecipitation and cell proliferation assays.

RESULTS

Elevated estrogen receptor (ER) transactivation, increased mRNA expression of early estrogen-responsive genes, progesterone receptor and insulin-like growth factor-I (IGF-I), and decreased protein levels of ER-alpha (ER alpha) were found in genistein-treated LM cells, but not SMC. Additionally, extracellular regulated kinase (ERK), Src homology/collagen (Shc) and ER alpha were transiently activated, and interactions between ER alpha and IGF-I receptor (IGF-IR) were rapidly induced by genistein in LM cells. Using ER antagonist ICI 182,780 and MAPK/ERK kinase (MEK) inhibitor PD98059, we found that these early events were inhibited and the proliferative effect of genistein on LM cells was abrogated.

CONCLUSIONS

ER alpha is involved in the transient activation of ERK/mitogen activated protein kinase (MAPK) by genistein via its early association with IGF-IR, leading to hyper-responsiveness of LM cells and confirming that ER signaling is enhanced by activation of ERK/MAPK in LM cells.

Stimulatory and inhibitory effects of genistein on human uterine leiomyoma cell proliferation are influenced by the concentration

BACKGROUND

Due to dietary exposure of women to genistein, a soy-derived phytoestrogen, and the estrogen responsiveness of uterine leiomyomas 'fibroids', we evaluated the effects of genistein (0.001-50 microg/ml) on human uterine leiomyoma (UtLM) cells versus uterine smooth muscle cells (UtSMCs) in vitro.

METHODS

Light microscopy was used to determine the effects of genistein on cell morphology. Proliferation was assessed using a colorimetric assay and proliferating cell nuclear antigen (PCNA) immunocytochemistry. Flow cytometry was used to quantitate cells in the S-phase and those undergoing apoptosis. A fluorometric assay and confocal microscopy were used to detect caspase-3 activity and apoptotic bodies, respectively.

RESULTS

In UtLM cells, low concentrations (< or = 1 microg/ml) of genistein stimulated proliferation, increased PCNA labeling and the percentage of cells in the S-phase, but this did not occur in UtSMCs. Higher concentrations (> or = 10 microg/ml) of genistein adversely affected the morphology, significantly inhibited proliferation, decreased PCNA labeling, increased caspase-3 activity and induced apoptosis in both cell types.

CONCLUSIONS

Genistein's effects are concentration-dependent in both cell lines. Lower concentrations elicit proliferative effects on UtLM cells only; whereas, higher concentrations alter morphology, inhibit proliferation, and increase caspase activity and apoptosis in both cell types, with the latter two effects being more extensive in UtSMCs.

Percutaneous Approach for Thecaloscopy of the Lumbar Subarachnoidal Space

INTRODUCTION

Endoscopy of the lumbar subarachnoidal space is named thecaloscopy, which has been used for diagnostic and therapeutic purposes. However, the insertion of the endoscope required microsurgical assistance from the skin into thecal sac in the lumbar region. The current study was applied to explore the possibility of a percutaneous approach for lumbar thecaloscopy insertion, transferring from the previous microsurgical procedure.

METHOD

A 2.8-mm fiberoptic endoscope (Storz and Co., Tuttlingen, Germany) was used in the study. In two fresh human cadavers, a thecaloscope was first inserted through a transsacral approach and the tip was advanced inside the thecal sac to the lumbar region for observation. A percutaneous endoscopic approach was performed with the Seldinger technique under fluoroscopic control into the lumbar subarachnoid space. After completing the endoscopic procedure, the lumbar subarachnoid space was exposed microsurgically for morphological investigation of rootlets and surrounding structures.

RESULTS

By the observation through a live video in the thecal sac, the percutaneous insertion of a 2.8-mm endoscope into the lumbar subarachnoidal space is feasible without any neural structural damage seen.

CONCLUSION

The percutaneous approach for flexible endoscopes into the lumbar subarachnoidal space is a practical option for the future of thecaloscopy.

LdCompare: rapid computation of single- and multiple-marker r2 and genetic coverage

The scale of genetic-variation datasets has increased enormously and the linkage equilibrium (LD) structure of these polymorphisms, particularly in whole-genome association studies, is of great interest. The significant computational complexity of calculating single- and multiple-marker correlations at a genome-wide scale remains challenging. We have developed a program that efficiently characterizes whole-genome LD structure on large number of SNPs in terms of single- and multiple-marker correlations.

AVAILABILITY

LdCompare is licensed under the GNU General Public License (GPL). Source code, documentation, testing datasets and precompiled executables are available for download at: http://www.affymetrix.com/support/developer/tools/devnettools.affx

Analysis of high density expression microarrays with signed-rank call algorithms

MOTIVATION

We consider the detection of expressed genes and the comparison of them in different experiments with the high-density oligonucleotide microarrays. The results are summarized as the detection calls and comparison calls, and they should be robust against data outliers over a wide target concentration range. It is also helpful to provide parameters that can be adjusted by the user to balance specificity and sensitivity under various experimental conditions.

RESULTS

We present rank-based algorithms for making detection and comparison calls on expression microarrays. The detection call algorithm utilizes the discrimination scores. The comparison call algorithm utilizes intensity differences. Both algorithms are based on Wilcoxon's signed-rank test. Several parameters in the algorithms can be adjusted by the user to alter levels of specificity and sensitivity. The algorithms were developed and analyzed using spiked-in genes arrayed in a Latin square format. In the call process, p-values are calculated to give a confidence level for the pertinent hypotheses. For comparison calls made between two arrays, two primary normalization factors are defined. To overcome the difficulty that constant normalization factors do not fit all probe sets, we perturb these primary normalization factors and make increasing or decreasing calls only if all resulting p-values fall within a defined critical region. Our algorithms also automatically handle scanner saturation.

[A further study on potential of microsatellite analysis of urine in diagnosis of bladder cancer]

OBJECTIVES

To investigate the application value of microsatellite analysis of voided urine in diagnosis of bladder cancer and compare the advantages and disadvantages of this method and urine cytology.

METHODS

Thirteen microsatellite markers, including the nine markers used in the authors' previous study and another four new markers, were tested on urine DNA from 143 individuals with or without bladder lesions in a blinded fashion. Urine cytology was applied at the same time.

RESULTS

The urine DNA from 89% (97/109) of the patients with bladder cancer, 86% (6/7) of the patients with inverted papilloma of the bladder, 3 out of 7 patients with cystitis and one patient with hematuria of unknown cause showed alterations, at least, in one of the 13 microsatellite markers, while the 19 individuals without bladder lesion had no change at any of these loci. Nucleic atypia or suspicious cancer cells were detected by routine cytology in the urine of the 3 patients with cystitis and one patient with hematuria of unknown cause who showed alterations of microsatellite in their urine sediments. Among the 81 cases of bladder cancer whose urine was examined by both microsatellite analysis and routine cytology, 73 cases (90%), of various stage or grade, were identified by microsatellite analysis, while only 41 cases (51%), mainly at advanced stage, were detected by cytology. Cancer cells were detected in the urine sediments of 4 of the 12 cases that were not identified by microsatellite analysis.

CONCLUSION

Microsatellite analysis of urine is useful for detection of bladder cancer. Microsatellite analysis and urine cytology could be complementary to each other.

A comparison between microsatellite analysis and cytology of urine for the detection of bladder cancer

We have studied, in a blinded fashion, cytology and microsatellite analysis on urine sediments of 143 Chinese with or without bladder lesions. Microsatellite analysis succeeded in all 143 individuals, while cytology could not be performed on 42 subjects due to insufficient urine samples. Both microsatellite analysis and routine urine cytology succeeded in 81 bladder cancer patients. Seventy-three patients (90%) were identified by microsatellite analysis, while only 41 patients (51%) were identified by cytology. However, four patients were identified by routine cytology but not by microsatellite analysis. Our results proved that microsatellite analysis is more sensitive than routine cytology but the two methods are complementary to each other.

Evidence for lactate uptake after rat fluid percussion brain injury

Traumatic brain injury (TBI) places enormous early energy demand on brain tissue to reinstate normal ionic balance. Glucose declines and lactate increases after TBI as demonstrated in clinical and lab studies, suggesting increased glycolysis. This led us to hypothesize that high extracellular fluid (ECF) lactate may be beneficial after TBI. We measured cerebral dialysate lactate and glucose, and arterial lactate and glucose, before & after rat Fluid Percussion Injury (FPI) (2.06 +/- 0.13 atm) with and without i.v. lactate infusion (100 mM x 4.5 hours) to test the hypotheses that arterial lactate determines ECF lactate. 14C-lactate autoradiography was also performed, to demonstrate whether lactate is taken up by traumatized brain.

RESULTS

Dialysate lactate was always significantly higher than arterial. After lactate infusion, both the dialysate and the arterial lactate were significantly increased (P < 0.0001). Dialysate lactate increased within 10 min. following FPI, with significantly higher values in the lactate infusion group (82% higher with lactate infusion after FPI). Dialysate glucose fell following FPI, with a more severe decline in the saline group (129% lower), suggesting lactate infusion preserves or "spares" glucose in ECF. In our autoradiographic study, i.v. 14C-lactate accumulated at the injury site, with levels 2-4 times higher than in contralateral cortex. In conclusion, arterial lactate augmentation thus increases brain dialysate lactate and results in less reduction in ECF glucose, after FPI. Infused lactate accumulates at the injury site, where metabolism is probably the greatest.

Mechanical injury alters volume activated ion channels in cortical astrocytes

Although astrocytic swelling is likely to mediate brain edema and high ICP after traumatic brain injury, the mechanism is not understood. We employed whole cell patch clamp electrophysiology and a stretch injury model to understand whether volume regulating ion currents are altered following cell injury. Mixed rat astrocytes and neurons were co-cultured on deformable silastic membranes. Mild-moderate cell injury was produced using a timed pulse of pressurized air to deform the silastic substrates by 6.5 mm. Then, ion currents were recorded with patch clamp methods. Cells were held at -65 mV and were stepped to +10 mV to monitor current changes.

RESULTS

In unstretched astrocytes, small amplitude currents were obtained under isotonic conditions. Hypotonic solution activated an outwardly-rectifying current which reversed near -40 mV. This current resembled a previously reported anion current whose activation may restore cell volume by mediating a net solute efflux. In contrast, stretch injured cells exhibited a large amplitude, nonrectifying current. This current was not due to non-specific ionic leakage, since it was fully suppressed by the cation channel blocker gadolinium. Activation of novel stretch-activated cation currents may exacerbate cell swelling in injured astrocytes. Stretch injured astrocytes thus express a dysfunctional cation current as opposed to an osmoregulatory anion current. This mechanism, if present in vivo, may contribute to the cytotoxic swelling seen after traumatic brain injury.

[Construction and expression of a new humanized salmon calcitonin variant]

OBJECTIVE

To study the reduction of immunogenicity of salmon calcitonin (sCT).

METHODS

A new (11-17) humanized salmon calcitonin variant gene (11-17) hsCT was designed and synthesized to construct recombinant expression vector and express in E.coli G1724 with tryptophan. The fusion protein of humanized salmon calcitonin and thioredoxin (Trx-hsCT) obtained from the bacterial by means of osmotic pressure; The bioactivity of Trx-hsCT was estimated by serum calcium reduction method in rat; The quantitative Western blot analysis was used for detecting the immunogenicity of hsCT.

RESULTS

Recombinant expressing vector pTrxFus-hsCT was expressed in high level and soluble in E.coli G1724, reaching 46% of total bacterial protein and obtaining the fusion protein of 90% purity; Special bioactivity of hsCT was preserved that of half pre-sCT and its immunogenicity reduced over 50% that of pre-sCT.

CONCLUSION

Obtain a new humanized salmon calcitonin variant(11-17) hsCT which maintains a rather high bioactivity over pre-sCT and decreases distinctly its immunogenicity.

Presence of DNA fragmentation and lack of neuroprotective effect in DFF45 knockout mice subjected to traumatic brain injury

BACKGROUND

Apoptosis plays an important pathophysiologic role in neuronal cell loss and associated neurologic deficits following traumatic brain injury (TBI). DNA fragmentation represents one of the characteristic biochemical features of neuronal apoptosis and is observed after experimental TBI. DFF45 and DFF40 are essential for DNA fragmentation in various models of apoptosis.

MATERIALS AND METHODS

We used mice deficient in DFF45 and wild-type controls. Oligonucleosomal DNA fragmentation induced by TBI was analyzed using in vivo and in vitro assays. Expression and integrity of DFF45 and DFF40 proteins was assessed by Western analysis. Other outcome measurements included neurologic scoring, learning/memory tests, lesion volume measurements (MRI), and assessment of cell viability in vitro among others.

RESULTS

We compared the effects of controlled cortical impact (CCI) trauma in DFF45 knockout mice and wild-type controls. Analysis of TBI-induced DNA fragmentation in brain cortex from wild-type and DFF45 knockout mice indicates that, although somewhat delayed, oligonucleosomal cleavage of DNA occurs after TBI in DFF45 knockout mice. DFF45 knockouts showed no significant differences in behavioral outcomes or lesion volumes after TBI as compared to wild-type controls. Using an in vitro reconstitution system, we also demonstrated that cleavage of DFF45 by caspase-3 is not sufficient for DNA fragmentation induced by protein extracts from rat brain cortex. We found that endonuclease activity induced in rat brain cortex following TBI depends on the presence of Mg2+ and Ca2+, but is not inhibited by Zn2+. Primary neuronal cultures from DFF45 knockouts failed to show DNA laddering in response to staurosporine, but did show prominent, albeit delayed, DNA fragmentation following treatment with etoposide. In contrast, primary neurons from wild-type animals demonstrated marked DNA fragmentation following treatment with staurosporine or etoposide.

CONCLUSIONS

The results of this study suggest that, in addition to DFF45/40, other endonucleases may be essential for chromatin degradation during neuronal apoptosis in adult brain after TBI.

[The role of dexamethasone on airway wall remodeling]

OBJECTIVE

To investigate the role of inhaled dexamethasone on airway wall remodeling.

METHODS

Asthmatic guinea pig models were established, after guinea pigs inhaled ovalbumin and dexamethasone, the thickness of airway wall was determined by contour tracing, using a digitizing pad and microcomputer. To culture airway smooth muscle cells, observe the effect of histamine, thromboxane A(2) and dexamethasone on cultured cells.

RESULTS

The mean thickness of airway smooth muscle in asthma group was (90 +/- 14) micrometer, greater than that of control (54 +/- 7) micrometer (P < 0.01); the airway smooth muscle layer in dexamethasone group (61 +/- 11) micrometer was thinner than that of asthma group (P < 0.01). [(3)H]-TdR incorporation in histamine group (2 950 +/- 205) counts/min was higher, comparing to that of the control (613 +/- 52) counts/min (P < 0.01); [(3)H]-TdR incorporation in dexamethasone group was (1 067 +/- 96) counts/min, lower than those of histamine group (P < 0.01).

CONCLUSIONS

Dexamethasone could prevent airway remodeling, and had no harmful effect on airway wall.

[Determination of three principal components in chuanjing tablets by using high performance liquid chromatography]

Uniform design method was employed to optimize the mobile phase of HPLC in order to determine simultaneously three principal components, theophylline, amobarbital and methylephedrine hydrochloride, in Chuanjing tablet, a compound preparation for asthma and cough. The stationary phase was ODS and the optimal mobile phase composition was V (0.015 mol/L phosphate buffer containing 0.3% triethylamine, pH 4.9): V (methanol) = 35:65. The detection was performed at 215 nm and the sensitivity was time programmed for simultaneous determination of minor and major components. Caffeine was selected as the internal standard. A baseline separation was achieved within 10 min. The linear ranges for theophylline, amobarbital and methylephedrine hydrochloride were 0.03 g/L-0.20 g/L, 7.5 mg/L-50.0 mg/L and 7.5 mg/L-50.0 mg/L, recoveries 99.7%-102.6%, 98.5%-100.2% and 98.0%-102.7%, inter-day RSDs 0.23%-1.2%, 0.35%-2.5%, 0.33%-1.6% respectively. This HPLC method is rapid and accurate, and suitable for the quality control of the preparation.

Brain lactate uptake increases at the site of impact after traumatic brain injury

Although glucose is the main carbohydrate energy substrate for the normal brain, several studies published over the last 10 years now challenge this assumption. The activated brain increases its metabolism to meet increased energy demands by glycolysis after injury. In vitro studies now show that lactate alone can serve as an energy source to maintain synaptic function. In this study, we used 14C-lactate to test the hypothesis that blood lactate is acutely taken up by the injured brain, after fluid percussion injury (FPI) in the rat. 50 microCi radioactive lactate was injected i.v. immediately after FPI, in injured and sham rats. After 30 min, the brain was removed, frozen, and cut into 20 microm sections for autoradiography. Uptake of 14C-label was mainly concentrated at the injury site (2.5 times greater) although uninjured brain also took up the 14C-label. This increased concentration of radioactive lactate at the injury site suggests that the injured brain may use the lactate as an energy source.

Lactate/glucose dynamics after rat fluid percussion brain injury

Traumatic brain injury (TBI) places enormous early energy demand on brain tissue to reinstate normal ionic balance. Clinical studies have demonstrated a decline in extracellular fluid (ECF) glucose and an increase in lactate after TBI. In vitro studies suggest that this increase in lactate is mediated by increased glutamate and may provide a metabolic substrate for neurons, to aid in ionic restoration. This led us to hypothesize that high ECF lactate may be beneficial in recovery following TBI, where major ionic flux has been shown to occur. In this study, we measured cerebral dialysate lactate and glucose, and arterial lactate and glucose, before and after rat lateral fluid percussion brain injury (FPI; 2.06 +/- 0.13 atm) with and without IV lactate infusion (100 mM X 0.65 mL/h X 5 h) to test the hypothesis that arterial lactate can influence ECF lactate. Dialysate lactate increased within 10 min following FPI, with higher values in the lactate infusion group. Following FPI, the dialysate lactate increase was 238% with lactate infusion versus 171% increase with saline infusion. Dialysate glucose fell immediately following FPI, with a more severe decline in the saline group. The glucose decrease was 231% greater in the IV saline group. Furthermore, in the lactate infusion group, the dialysate glucose levels recovered to baseline levels by 4 h after injury, whereas they remained depressed through out the experiment, in the saline infusion group. We conclude that arterial lactate augmentation can increase brain dialysate lactate, and result in more rapid recovery of dialysate glucose after FPI. This may indicate a beneficial role for lactate, that may be potentially useful in the clinical situation, after TBI.

Dicyclomine, an M1 muscarinic antagonist, reduces infarct volume in a rat subdural hematoma model

The rat subdural hematoma (SDH) model produces a zone of ischemic brain damage within the hemisphere beneath the SDH. Previous studies have measured large increases in extracellular acetylcholine during cerebral ischemia in the rat. We examined infarct volume after selectively blocking muscarinic M1 receptors with dicyclomine during SDH. Rats were anesthetized with isoflurane (2%), intubated, and femoral artery and vein cannulated. Autologous blood (0.375 ml) was injected (0.05 ml/min) under the dura of the right parietal cortex. Dicyclomine (5 mg/kg, i.v.) was injected at 5 min after and again at 2 h after completion of the subdural blood infusion. Blood pressure and intracranial pressure (ICP) were continuously measured. At 4 h after SDH rats were euthanized, brains sectioned, and immunoreacted with glia fibrillary acidic protein. Cortical infarct volume was quantified in coronal brain sections at 0.7-mm intervals from +1.0 mm to -3.9 mm relative to bregma. Infarct volume in drug-treated rats (n = 10) 22.1 +/- 6.99 mm3 was significantly smaller (p < 0.02) than vehicle treated rats (n = 10) 56.7 +/- 9.59 mm3. ICP, blood pressure and cerebral perfusion pressure were not significantly different between groups. These data suggest that activation of M1 muscarinic receptors during an ischemic event may contribute to the development of subsequent pathology.

Effects of levonorgestrel-releasing subdermal contraceptive implants on bone density and bone metabolism

A prospective, randomized clinical trial observed the effects of Norplant long-term contraceptive implants and domestic implants similar to Norplant on bone mineral density and bone metabolism in female acceptors for 1 year. Bone mineral density (BMD) and bone mineral content (BMC) of lumbar 2-4 and proximal femur of 61 normal women of child-bearing age were measured by dual energy x-ray absorptiometry (DEXA) before and 12 months after implants insertion in both groups. BMD and BMC of lumbar 2-4 in both groups 12 months after implant insertion significantly increased (p < 0.01); with an average increase of 2.40% and 3.34%, respectively in the Norplant implant group, and 2.75% and 4.47%, respectively in the domestic implant group. Urine hydroxyproline and creatinine ratio (Hop/Cr) in the domestic implant group significantly decreased (p < 0.01). There was no significant differences in the effects on BMD and BMC of lumbar spine and femur and on bone metabolism between the two groups of contraceptive implants (p > 0.05). Levonorgestrel releasing contraceptive subdermal implants were not deleterious to the skeleton in women of child-bearing age. There was no significant effect on achieving maximum bone mass in young women.

Fluid percussion brain injury exacerbates glutamate-induced focal damage in the rat

The role of glutamate-mediated neuronal damage in neurotrauma remains controversial. The cerebral levels measured in patients by microdialysis are sufficient to kill neurons in culture, but not in the intact brain of the normal rat. A synergistic effect between excitatory amino acid-mediated damage and other posttrauma mechanisms must therefore be proposed, if glutamate is indeed a significant cause of posttraumatic brain damage. The presence of such a synergistic mechanism was therefore investigated by combining in vivo glutamate perfusion and fluid percussion injury (FPI). Twenty-four adult male Sprague Dawley rats were randomly assigned to three groups: (1) vehicle (n = 9): mock cerebrospinal fluid (CSF) perfusion plus FPI; (2) glutamate + FPI (n = 9): 0.1 M glutamate intracortical perfusion plus FPI; and (3) glutamate without FPI (n = 6). After preparation for central FPI, at a moderate level of injury (2 +/- 0.5 atm), glutamate or mock CSF perfusion was performed via a CMA/12 microdialysis probe (3 mm). Animals were then perfusion fixed, under deep anesthesia, after 3-h survival, for volumetric histopathology. The glutamate perfusion + FPI group (2.42 +/- 1.63 mm3) produced a significantly bigger lesion than mock CSF perfusion + FPI (0.063 +/- 0.41 mm3) and glutamate perfusion alone (1.00 +/- 0.47 mm3). Traumatic brain injury thus seems to enhance glutamate-mediated brain damage, and this may be due to qualitative changes induced in ion channels and receptors, such as the N-methyl-D-aspartate channel, after shear injury.

Reducing hemoglobin oxygen affinity does not increase hydroxyl radicals after acute subdural hematoma in the rat

Extensive evidence is available to show the importance of ischemia after severe human head injury. We have previously shown that pharmacologically increasing the release of oxygen in brain tissue where the local oxygen pressure is low reduces infarct size in animal models. To study the possible negative effects of this strategy, we tested the effect of an allosteric modifier of hemoglobin (RSR13) on free radical production in the rat acute subdural hematoma (ASDH) model, both under normoxic as well as under hyperoxic, normobaric conditions. When compared to baseline, induction of ASDH resulted in a significant increase (p < 0.05) in 2,3-DHBA (2,3 dihydroxybenzoic acid, produced from salicylate after attack by hydroxyl radicals) at 30 and 60 min postinduction, both for the control group (39% and 91%) as well as the RSR13-treated group (41% and 62%). The 2,5-DHBA also increased significantly (p < 0.05) in the drug-treated animals at the 30- and 60-min time points when compared to baseline (49% and 77%). At all time points, except the 30-min, the increase in 2,3-DHBA was less marked in the RSR13 animals than in the control group. Similarly, the 2,5-DHBA increase after ASDH was lower at all time points except for the 30-min time point in the RSR13-treated group. These results indicate that enhanced tissue oxygen release by the allosteric modifier of hemoglobin RSR13 does not increase hydroxyl radical production after ASDH. Clinical trials are needed to test this compound in humans after severe head injury.

[The expression study of human stem cell factor (hSCF) in E. coli]

OBJECTIVE

To improve the expression level of recombinant human stem cell factor (rhSCF).

METHODS

With PCR techniques and synthesized oligonucleotide as primers, the number of nucleotides between the SD sequence and the starting codon ATG of human stem cell factor cDNA was altered, and the preferable codons of E. coli in the N-terminal amino acid sequence were selected.

RESULTS

SDS-PAGE electrophoresis indicated that the ratio of expressed rhSCF to total E. coli proteins increased from 12% to 40% by thermal inducing. With DNA sequencing, the reading frame of the gene was proved to be correct. The sequence of 17 N-terminal amino acids of purified recombinant hSCF has been proved to be identical to the natural hSCF, except the first amino acid-Met.

CONCLUSIONS

These studies suggest that the 5'-flanking region of hSCF cDNA plays an important role in its gene expression.

[Measurement of interfragmentary micromovement induced by mechanical vibration with accelerometers in vitro]

The interfragmentary micromovement induced by mechanical vibration was measured in vitro in seven preserved adult cadaveric femurs by using accelerometers. Accuracy analysis of this method indicated that it can detect relative interfragmentary micromovement as small as 0.1 mm or below under certain range of frequency. Also, the results have shown that the mechanical vibration can induce interfragmentary micromovement under intramedullary nailing, but it can not do so under plate fixation.

Increased free radical production due to subdural hematoma in the rat: effect of increased inspired oxygen fraction

Acute subdural hematoma (ASDH) complicates about 15%-20% of severe head injury patients and is one of the major causes for bad outcome, yet the pathomechanisms involved are not well understood. This study has employed a recently developed technique to determine whether ASDH induces free radicals in the underlying brain. We also studied the effect of increased inspired oxygen fraction (FiO2) on free radical production, both in the normal rat brain and after ASDH induction. Twelve male Sprague Dawley rats were studied over 5 h (2 h of FiO2 = 30%, 3 h of FiO2 = 100%). Hydroxyl radical production was measured with microdialysis using the salicylate trapping technique by quantitating the 2,3 dihydroxy benzoic acid (2,3 DHBA) and 2,5 dihydroxy benzoic acid (2,5 DHBA), degradation products, in either noninjured brain (n = 6) or after ASDH (n = 6). Both 2,3 DHBA and 2,5 DHBA increased significantly by 39% and 108%, respectively, after the induction of the SDH (p < 0.05). By increasing the FiO2 to 100%, 2 h after ASDH induction, the 2,3 DHBA and 2,5 DHBA further increased only slightly (ns). After increasing the FiO2 to 100% in the noninjured group, the mean level of 2,3 DHBA increased by 56% (p = 0.06, ns). The level of 2,5 DHBA in the dialysate increased significantly by 56% (p < 0.05), when the FiO2 was increased to 100% ASDH results in a significant increase in free radical production. At the same time, prolonged increase in FiO2 does not lead to further increase in free radical production in the injured brain.

Proliferative potentials of glioma cells and vascular components determined with monoclonal antibody MIB-1

Proliferative activity in 78 glioma specimens was assessed immunohistochemically by determining proliferating index of tumor cells (PTC-PI) and endothelial cells (PEC-PI) using the MIB-1 monoclonal antibody. The PTC-PI of anaplastic astrocytoma (9.0 +/- 5.8: mean +/- standard deviation) was significantly higher than that of astrocytoma (1.2 +/- 0.4, < 0.01), and lower than that of glioblastoma multiforme (12.0 +/- 5.6, < 0.05). We then compared PTC-PI values, patients' age and extent of tumor resection with the prognosis of patients with malignant glioma (both glioblastoma and anaplastic astrocytoma). Kaplan-Meier survival rate analysis demonstrated higher survival rates in patients with less than 8.0% of PTC-PI at 5 and 10 years (p < 0.05). The mean age of patients who survived more than a year was lower than that of patients who died within a year (53.0 y.o., vs. 59.7 y.o., p < 0.01). Total or subtotal resection of the tumor was more often performed in the former than latter patients (51% vs. 21%, p < 0.01). These results suggested PTC-PI provides useful information which may allow better assessment of the biological behavior and clinical prognosis of glioma, in addition to histological grading, patients' age and extent of tumor resection. While the average PEC-PI value (3.3) was lower than that of PTC-PI (7.0), there was a significantly close relationship between PTC- and PEC values (p < 0.01), providing an impetus to develop novel therapies directed toward suppression of microvascular regeneration.

Effect of CP101,606, a novel NR2B subunit antagonist of the N-methyl-D-aspartate receptor, on the volume of ischemic brain damage off cytotoxic brain edema after middle cerebral artery occlusion in the feline brain

BACKGROUND AND PURPOSE

The purpose of this study was to test the hypothesis that the neuroprotective compound CP101,606 will ameliorate the increase in lactate, retard the development of cytotoxic edema, and decrease the infarct volume after ischemic stroke.

METHODS

Seventeen adult cats were allocated to control (n = 7) and CP101,606-treated groups (n = 10). Transorbital middle cerebral artery occlusion was performed under anesthesia. Extracellular fluid lactate by microdialysis as well as infarct volume measurement by triphenyltetrazolium chloride (TTC)-stained section, with and without neuroprotective agents, was used to determine the value of these potential "surrogate markers" of ischemic damage.

RESULTS

The control group showed an increased dialysate lactate (15.5% increase) at 30 minutes and a peak (332.0% increase) in dialysate lactate at 1 hour after middle cerebral artery occlusion compared with the drug-treated group. Significant differences between control and drug-treated groups were seen in the rate of fall of the apparent diffusion coefficient at both 1 and 5 hours. A close correlation was seen between the 1- and 5-hour apparent diffusion coefficient maps and the TTC-stained sections. There was a significantly smaller lesion in the CP101,606-treated group (62.9% reduction in infarct size compared with the control group; P < .001).

CONCLUSIONS

CP101,606 ranks very highly among the current neuroprotection candidates for clinical trials, and its excellent safety record in both animals and phase II studies in conscious, moderate head injury patients suggests that it will be highly effective in human occlusive stroke.

Proliferative potentials of glioma cells and vascular components determined with monoclonal antibody MIB-1

Proliferative activity in 78 glioma specimens was assessed immunohistochemically by determining proliferating index of tumor cells (PTC-PI) and endothelial cells (PEC-PI) using the MIB-1 monoclonal antibody. The PTC-PI of anaplastic astrocytoma (9.0 +/- 5.8: mean + standard deviation) was significantly higher than that of astrocytoma (1.2 +/- 0.4, < 0.01), and lower than that of glioblastoma multiforme (12.0 +/- 5.6, < 0.05). We then compared PTC-PI values with the prognosis of patients with malignant glioma (both glioblastoma and anaplastic astrocytoma). Kaplan-Meier survival rate analysis demonstrated higher survival rates in patients with less than 8.0% of PTC-PI at 5 and 10 years (p < 0.05). These results suggested PTC-PI provides useful information which may allow better assessment of the biological behaviour and clinical prognosis of glioma, in addition to histological grading. While the average PEC-PI value (3.3) was lower than that of PTC-PI (7.0), there was a significantly close relationship between them (p < 0.01), fostering the developments novel therapies directed towards suppression of microvascular regeneration.

Effects of mild hypothermia on cerebral blood flow-independent changes in cortical extracellular levels of amino acids following contusion trauma in the rat

The mechanism of hypothermic cerebroprotection after traumatic brain injury (TBI) is unknown. The present study was conducted to investigate the effects of mild hypothermia on the changes in cortical extracellular amino acids and cerebral blood flow (CBF) caused by cerebral contusion created in the rat parietal cortex by a weight-drop method. CBF in both normothermia (37 degrees C) and hypothermia (32 degrees C) groups, which was monitored using the hydrogen clearance technique, decreased significantly after contusion, but never fell below the threshold for ischemia. Cortical levels of glutamate, aspartate, glycine and taurine, which were measured by intracerebral microdialysis, were significantly increased after contusion in each group. However, these increases were greater in the hypothermic than in the normothermic rats. Normal plasma amino acid levels were high, and autoradiography following intravenous injection of 14C-labeled glutamate revealed marked extravasation of [14C]glutamate at the site of cortical impact. These results suggest that the post-traumatic increase in extracellular amino acids occurs independently of CBF reduction, and that extravasation of amino acids from the vascular compartment partly contributes to this increase. Hypothermic cerebroprotection in TBI is thus likely to occur through a mechanism other than reduction in interstitial excitatory amino acids. In TBI, it is postulated that the postsynaptic effects of hypothermia may be more important than the presynaptic effects, when CBF is kept above the ischemic threshold.

[cDNA cloning of human stem cell factor and its high level expression in E. coli]

The total RNA of HepG2 cell was extracted as the template by ultrocentrifuge method. The full length cDNA (0.8 kb) encoding the human stem cell factor (hSCF) was amplified by RT-PCR method. The cDNA encoding mature hSCF (0.5 kb) was sequenced and was recombined into the expression vector (PBV-220). The expression level of rhSCF in E. coli DH5 alpha was about 15% of the total protein.

[Increased promoter activity of human delta-globin gene with point mutation of C-T at site-64]

With PCR point mutation technique, the CCAAC box in the promoter region of delta-globin gene was changed into CCAAT which is required in the normal transcription of beta-globin gene at the corresponding site. The normal and mutant segments of the delta-globin promoter region obtained with each segment of about 300 bp (-280/+54 bp), a fragment sufficient for the requirement of its normal promoter function, were separately cloned into pUC19/Hinc II. After sequencing, it showed that the CCAAC box had been successfully changed into CCAAT without other mutations. The two segments were released by Nco I and BamH I, and were cloned into the corresponding site of plasmid pMG3 which has the firefly luciferase as its reporter gene. The positive clones were selected by Dot Blot and were comfirmed with restriction mapping. Then the two recombinant plasmids were transfected into HeLa cell line respectively and the promoter activities of the two fragments were identified by comparing the light intensity generated by the cell extracts when added with luciferase assay substrate. The results demonstrated that the luminescence of the mutant group is on average five times higher than that of the normal group, which indicate that the C-T mutation of the CCAAC box of delta-globin promoter region could increase its promoter activity. Our results have confirmed the hypothesis that the sequence of CCAAC box of human delta-globin gene is one of the main reasons which accounts for its low expression level. The author is now studying the specific DNA binding protein of the upstream promoter region of human delta-globin gene.