Simultaneous suppression of lignin, tricin and wall-bound phenolic biosynthesis via the expression of monolignol 4-O-methyltransferases in rice

Grass lignocelluloses feature complex compositions and structures. In addition to the presence of conventional lignin units from monolignols, acylated monolignols and flavonoid tricin also incorporate into lignin polymer; moreover, hydroxycinnamates, particularly ferulate, cross-link arabinoxylan chains with each other and/or with lignin polymers. These structural complexities make grass lignocellulosics difficult to optimize for effective agro-industrial applications. In the present study, we assess the applications of two engineered monolignol 4-O-methyltransferases (MOMTs) in modifying rice lignocellulosic properties. Two MOMTs confer regiospecific para-methylation of monolignols but with different catalytic preferences. The expression of MOMTs in rice resulted in differential but drastic suppression of lignin deposition, showing more than 50% decrease in guaiacyl lignin and up to an 90% reduction in syringyl lignin in transgenic lines. Moreover, the levels of arabinoxylan-bound ferulate were reduced by up to 50%, and the levels of tricin in lignin fraction were also substantially reduced. Concomitantly, up to 11 μmol/g of the methanol-extractable 4-O-methylated ferulic acid and 5-7 μmol/g 4-O-methylated sinapic acid were accumulated in MOMT transgenic lines. Both MOMTs in vitro displayed discernible substrate promiscuity towards a range of phenolics in addition to the dominant substrate monolignols, which partially explains their broad effects on grass phenolic biosynthesis. The cell wall structural and compositional changes resulted in up to 30% increase in saccharification yield of the de-starched rice straw biomass after diluted acid-pretreatment. These results demonstrate an effective strategy to tailor complex grass cell walls to generate improved cellulosic feedstocks for the fermentable sugar-based production of biofuel and bio-chemicals.

[A case report of death from toxic encephalopathy caused by emamectin·chlorfenapyr]

Emamectin·chlorfenapyr is insecticide compounded by emamectin benzoate and chlorfenapyr. There is no special antidote after poisoning, and the mortality rate of patients is very high. We admitted a case of toxic encephalopathy caused by oral administration of emamectin·chlorfenapyr. The clinical manifestations of patient were gastrointestinal symptoms, profuse sweating, high fever, changes in consciousness. After admitted to the hospital, despite active comprehensive treatment, the patient died of ineffective rescue eventually.

[Application of transbronchial cryobiopsy in the diagnosis of postoperative complications after lung transplantation: a report of 6 cases]

Objective: To investigate the efficacy and safety of transbronchial cryobiopsy (TBCB) after lung transplantation. Methods: The clinical characteristics, TBCB procedure, diagnosis and treatment, and outcomes of lung transplant recipients of 6 patients (all male, aged 33-67 years) with TBCB in China-Japan Friendship Hospital from May to November 2021 were retrospectively analyzed. Results: Among the 6 patients diagnosed by TBCB, there were 2 cases of organizing pneumonia, 1 acute cellular rejection, 1 antibody-mediated rejection, and 1 bronchiolitis obliterans, and 1 diffuse alveolar damage. After the clinical diagnosis was confirmed, the condition improved after adjustment of the treatments followed. There were no serious complications related to the TBCB procedure. Conclusion: TBCB is valuable and relatively safe in the diagnosis of complications after lung transplantation, but the indications need to be strictly controlled.

Percutaneous CT-Guided Microwave Ablation Combined with Vertebral Augmentation for Treatment of Painful Spinal Metastases

BACKGROUND AND PURPOSE

Percutaneous thermal ablation followed by vertebral augmentation is an emerging minimally invasive therapeutic alternative for the management of spinal metastases. This study aimed to retrospectively evaluate the effectiveness and safety of microwave ablation combined with vertebral augmentation for the treatment of painful vertebral metastases.

MATERIALS AND METHODS

Overall, 91 patients with 140 metastatic vertebrae who experienced refractory moderate-to-severe pain were treated with CT-guided microwave ablation and vertebral augmentation. Procedural effectiveness was determined using the visual analog scale, daily morphine consumption, and the Oswestry Disability Index preprocedurally and during follow-up. Local tumor control was assessed at follow-up imaging.

RESULTS

The procedure was technically successful in all patients. The median visual analog scale score and mean morphine dose were 6 (range, 4-10) and 77.8 (SD, 31.5) mg (range, 15-143 mg), preprocedurally; 5 (range 3-8) and 34.5 (SD, 23.8) mg (range, 0-88 mg) at 3 days; 4 (range, 2-7) and 28.7 (SD, 16.4) mg (range, 0-73 mg) at 1 week; 3 (range, 1-6) and 24.6 (SD, 13.2) mg (range, 0-70 mg) at 1 month; 3 (range, 1-6) and 21.70 (SD, 10.0) mg (range, 0-42 mg) at 3 months; and 3 (range, 1-8) and 21.0 (SD, 9.9) mg (range, 0-46 mg) at 6 months postprocedurally (all P < .05). A decrease in the Oswestry Disability Index score was also observed (P < .01). Local control was achieved in 94.8% of the treated metastatic vertebrae during the 6-month follow-up period. Asymptomatic cement leakage occurred in 42 (30%) treated vertebrae. A grade 3 neural injury was observed in 1 patient (1.1%). The patient's neurologic function returned to normal following treatment with mannitol, glucocorticoids, and radiation therapy.

CONCLUSIONS

This study demonstrates that percutaneous CT-guided microwave ablation combined with vertebral augmentation is a safe and effective minimally invasive intervention for the treatment of painful spinal metastases.

Transcriptome and metabolome analyses of the immune response to light stress in the hybrid grouper (Epinephelus lanceolatus ♂ × Epinephelus fuscoguttatus ♀)

Light intensity is an important environmental factor that affects fish growth and health through multiple physiological activities and metabolism and eventually impacts aquaculture harvest. There is a need to evaluate the fish stress response to light intensities, which will benefit aquaculture. Here, hybrid grouper (Epinephelus lanceolatus ♂ × Epinephelus fuscoguttatus ♀) was treated with three light intensities for evaluation of the light stress response, including high light intensity (1 250 lx), low light intensity (10 lx) and moderate light intensity (250 lx). Transcriptome analysis showed that a total of 71 318 unigene sequences were obtained with an N50 of 2 589 bp. Compared to the control group (250 lx), 1 697 differentially expressed genes (DEGs), a considerable quantity, were detected in the 1 250 lx group. Among those genes, 548 were upregulated, and the remaining 149 genes showed decreased expression. Comparatively small numbers of DEGs were detected in the 10 lx group; 54 out of 103 genes exhibited upregulated expression, and 49 genes showed downregulation. For further KEGG analysis, 82 DEGs were enriched in nine common signalling pathways in immunity, of which 73 DEGs were significantly inhibited in the 1 250 lx group. In contrast, only 11 DEGs were enriched in three immunity pathways, with nine DEGs showing a significant increase in the 10 lx group. The metabolome analysis revealed 59 and 44 differential metabolites (DMs) from the 1 250 lx and 10 lx groups, respectively. Of note, those DMs from the 1 250 lx-treated group were tendentiously involved in amino acid metabolism and lipid metabolism pathways, while the purine metabolism, amino acid metabolism and lipid metabolism pathways were mostly found in the 10 lx treatment group. In summary, our data indicated that high light intensity significantly inhibited the immune response in hybrid grouper, while low light intensity presented low stimulation of immune activity. In addition, both high and low light intensity could inhibit protein synthesis and amino acid metabolism. Taken together, hybrid grouper exhibited a much milder stress response to low light intensity than to high light intensity.

Association between Skeletal Muscle Strength and Dysphagia among Chinese Community-Dwelling Elderly Adults

OBJECTIVES

Swallowing disorder is a health burden for the elderly in China. This study aimed to investigate the prevalence of dysphagia and to test the association between skeletal muscle strength and swallowing problems among community-dwelling older adults.

DESIGN

A cross-sectional study.

SETTING

Community-dwelling Chinese elderly in China.

PARTICIPANTS

3361 adults aged 65 years or above were involved, among which 1740 (51.8%) were female, with average age of 72.64 (Standard deviation, SD=6.10) years old.

MEASUREMENTS

Handgrip strength (HGS) was used to evaluate skeletal muscle strength. Dysphagia assessment was performed using the Eating Assessment Tool-10 (EAT-10) and the 30mL water swallow test (WST). Binary logistic regression was used to evaluate the relationship between skeletal muscle strength and dysphagia, and covariates as age, gender, material status, etc. were adjusted.

RESULTS

The prevalence of dysphagia were 5.5% and 12.9%, screened by EAT-10 and 30mL WST respectively. Participants with dysphagia showed lower HGS (21.73 ± 9.20 vs. 25.66 ± 11.32, p<0.001, by EAT-10; 20.26 ± 9.88 vs. 26.22 ± 11.28, p<0.001, by WST). The adjusted model suggested that muscle strength is a protective factor for swallowing disorders (adjusted OR=0.974, 95%CI: 0.950-0.999, by EAT-10; adjusted OR=0.952, 95%CI: 0.933-0.972, by WST). Subgroup analyses of WST found the effects were significant among participants aged in 70-74 years group and ≥75 years group, rather than those aged under 70.

CONCLUSION

Dysphagia was significantly associated with skeletal muscle strength among the community-dwelling elderly population. Effective interventions should be taken to manage the decline of muscle strength for the older adults, especially early prevention before 70 years old.

Citrobacter rodentium Induces Tissue-Resident Memory CD4+ T Cells

Tissue-resident memory T cells (TRM cells) are a novel population of tissue-restricted antigen-specific T cells. TRM cells are induced by pathogens and promote host defense against secondary infections. Although TRM cells cannot be detected in circulation, they are the major memory CD4+ and CD8+ T-cell population in tissues in mice and humans. Murine models of CD8+ TRM cells have shown that CD8+ TRM cells maintain tissue residency via CD69 and though tumor growth factor β-dependent induction of CD103. In contrast to CD8+ TRM cells, there are few models of CD4+ TRM cells. Thus, much less is known about the factors regulating the induction, maintenance, and host defense functions of CD4+ TRM cells. Citrobacter rodentium is known to induce IL-17+ and IL-22+ CD4+ T cells (Th17 and Th22 cells, respectively). Moreover, data from IL-22 reporter mice show that most IL-22+ cells in the colon 3 months after C. rodentium infection are CD4+ T cells. This collectively suggests that C. rodentium may induce CD4+ TRM cells. Here, we demonstrate that C. rodentium induces a population of IL-17A+ CD4+ T cells that are tissue restricted and antigen specific, thus meeting the criteria of CD4+ TRM cells. These cells expand and are a major source of IL-22 during secondary C. rodentium infection, even before the T-cell phase of the host response in primary infection. Finally, using FTY 720, which depletes circulating naive and effector T cells but not tissue-restricted T cells, we show that these CD4+ TRM cells can promote host defense.

Wild-type phosphatase and tensin homolog deleted on chromosome 10 improved the sensitivity of cells to rapamycin through regulating phosphorylation of Akt in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is one of the most frequently diagnosed cancers in China, but the etiology and mode of carcinogenesis of this disease remain poorly understood. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN), as a negative regulator of Akt/mTOR pathway, frequently mutates or is inactive in many cancers. Although mTOR has been thought a promising cancer therapeutic target, the sensitivity of tumor cells to rapamycin was still to be revaluated. In this study, we measured the effects of rapamycin on cell proliferation and phosphorylation of Akt in ESCC cells with varying degrees of differentiation. And then, the relationship between PTEN status and the sensitivity of cells to rapamycin was investigated in EC9706 cells with or without wild-type PTEN in vitro and in vivo. The results demonstrated ESCC cells with poor differentiation were insensitive to rapamycin of high concentration and rapamycin obviously promoted the phosphorylation of Akt in these cells, but it had no obvious effects on p-Akt in cells with well differentiation. Also, we showed that wild-type PTEN improved the sensitivity of poor differentiation cells to rapamycin through inhibiting phosphorylation of Akt in vitro and in vivo. This study explored the possible molecular mechanism of some ESCC cells insensitive to rapamycin and provided a measure for treating ESCC patients with PTEN inactivation using mTOR inhibitors.

The MYB107 Transcription Factor Positively Regulates Suberin Biosynthesis

Suberin, a lipophilic polymer deposited in the outer integument of the Arabidopsis (Arabidopsis thaliana) seed coat, represents an essential sealing component controlling water and solute movement and protecting seed from pathogenic infection. Although many genes responsible for suberin synthesis are identified, the regulatory components controlling its biosynthesis have not been definitively determined. Here, we show that the Arabidopsis MYB107 transcription factor acts as a positive regulator controlling suberin biosynthetic gene expression in the seed coat. MYB107 coexpresses with suberin biosynthetic genes in a temporal manner during seed development. Disrupting MYB107 particularly suppresses the expression of genes involved in suberin but not cutin biosynthesis, lowers seed coat suberin accumulation, alters suberin lamellar structure, and consequently renders higher seed coat permeability and susceptibility to abiotic stresses. Furthermore, MYB107 directly binds to the promoters of suberin biosynthetic genes, verifying its primary role in regulating their expression. Identifying MYB107 as a positive regulator for seed coat suberin synthesis offers a basis for discovering the potential transcriptional network behind one of the most abundant lipid-based polymers in nature.

In vivo Toll-like receptor 5 (TLR5) imaging with radiolabeled anti-TLR5 monoclonal antibody in rapamycin-treated mouse allogeneic skin transplantation model

BACKGROUND

In organ transplantation, increasing evidence, both in experimental and human studies, indicates that Toll-like receptor (TLR) activation is involved in the innate immune recognition of allograft. TLR5, the only protein recognition receptor of TLRs, is indicated potentially to be the immune regulation target. This study was designed to determine whether TLR5 could be a biomarker for in vivo allograft visualization, after immunosuppressant rapamycin treatment, using radiolabeled sodium iodide ((131) I)-anti-TLR5 monoclonal antibody (mAb).

METHODS

BALB/c mice were transplanted with C57BL/6 skin, with/without rapamycin treatment (the rapamycin-treated group and the phosphate buffered saline [PBS]-rejection group, respectively). In vivo dynamic whole-body phosphor-autoradiography and ex vivo biodistribution studies were conducted after (131) I-anti-TLR5 mAb injection.

RESULTS

Dynamic phosphor-autoradiography imaging showed clear graft localization from 12 h onward. At 72 h after injection, graft uptake quantified from images was higher for the rapamycin-treated group (26,448 ± 904 digital light units [DLU]/mm(2) ), compared with the PBS-treated allo-rejection group (9176 ± 576 DLU/mm(2) ). Treatment with anti-TLR5 mAb inhibited graft uptake. Organ biodistribution study reflected the same tendency, and (131) I-anti-TLR5 mAb uptake reached a maximum of 12.05 ± 1.86 %ID/g (percent injected dose per gram) at 1 h, and graft-to-native skin ratio reached 8.10 ± 0.10 %ID/g at 72 h after injection in rapamycin-treated grafts.

CONCLUSION

Radiolabeled anti-TLR5 mAb showed higher uptake in allo-treated grafts compared with allo-rejection grafts, which was proved by non-invasive dynamic phosphor-autoradiography imaging, and invasive ex vivo biodistribution. Radiolabeled anti-TLR5 mAb is a new tracer for non-invasive in vivo imaging of TLR5 in rapamycin-treated allograft.

Abstract P3-02-04: QM-FISH analysis of the genes involved in the G1/S checkpoint signaling pathway in triple-negative breast cancer

OBJECTIVES: To analyze copy number alterations(CNAs) of the genes involved in the G1/S checkpoint signaling pathway of triple-negative breast cancer (TNBC) and non- triple-negative breast cancer(non-TNBC) and in order to find specific CNAs associated with overall survive for TNBC.In all,to provide an effective target for future treatment.

METHODS: We selected the samples randomly form Tianjin Cancer Hospital between August, 2006 and August, 2007,which contained one hundred TNBC cases and one hundred non-TNBC cases. Quantitative mμlti-gene fluorescence in situ hybridization (QM-FISH) was used to study CNAs of the genes involved in the G1/S checkpoint signaling pathway, including CCND1,c-Myc,p21, CHEK2, p16, Rb1, Mdm2and p53.

RESULTS: The amplification rates of c-Myc and the deletion rates of p53 in TNBC tended to be higher than those in non-TNBC, whereas the amplification rates of CCND1 and Mdm2 in non-TNBC tended to be higher than those in TNBC. In Kaplan-Meier analysis, the amplification of CCND1 (P = 0.02) and c-Myc (P = 0.02) as well as the deletion of p53 (P = 0.01) predicted worse survival in the TNBC group. While in the non-TNBC group, the amplification of CCND1 (P = 0.01) and Mdm2 (P = 0.04) as well as the deletion of p53 (P = 0.049) were associated with worse survival. The amplification of c-Myc and the deletion of p53 in TNBC were associated with higher mortality risk (HR,2.87;95%CI,1.14-7.21[P = 0.03]; HR, 3.34;95%CI, 1.22-9.09 [P = 0.02]), whereas the mortality risk tended to be higher in the patients with amplification of CCND1 (HR, 4.35;95%CI,1.23-15.39 [P = 0.02])in non-TNBC.

CONCLUSIONS: The amplification rates of c-Myc and deletion rates of p53 in TNBC tended to be higher than those in non-TNBC, whereas the amplification rate of CCND1 and Mdm2 tended to be higher in non-TNBC. c-Myc and p53 were independent prognostic factors for TNBC, while CCND1 was the independent prognostic factors for non-TNBC.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-02-04.

Abstract P1-08-05: The prognostic significance of Ki-67 expression before and after neoadjuvant anthracycline-taxane-based chemotherapy in different biological breast cancer phenotypes

Purpose

This study was conducted to analyze the Ki-67 expression before and after neoadjuvant chemotherapy and clinical pathology characteristics of different biological breast cancer phenotypes at our center. A correlation study was performed between Ki-67 index change and the prognosis of different biological breast cancer phenotypes and prognosis in Northern China.

Methods

A regression analysis was performed on 213 patients with invasive breast carcinoma accepted NAC admitted to Tianjin Medical University Cancer Institute and Hospital of Breast Surgery from January 2007 to April 2008. These patients were subtyped by hormone receptor status and HER2 status.The Ki67 index (percentage of Ki67-positive cancer nuclei) were determined immunohistochemically. The prognostic value of the Ki-67 index for different biological breast cancer phenotypes disease-free survival (DFS) and overall survival (OS) was investigated by use of Kaplan–Meier curves and multivariable Cox regression.

Results

The overall pathologic CR (pCR) rate, defined as no invasive residuals in breast and axilla, was 17.8%. The highest pCR rate of 32.1% was observed in patients with HR-/HER2+ tumors, which is 11.4%, 20.0% and 26.2% in HR+/HER2- HR+/HER2-,HR+/HER2+and HR-/HER2- tumor respectively(P = 0.024).The Ki-67 expression of pre-NAC and post-NAC have prognostic significance in HER2- breast cancer, which have not significance different in HER2+ breast cancer:The best Ki-67 idex cut point of pre-NAC and post-NAC to predict long-term survival was respectively 20% and 10% in HR+/HER2- breast cancer. Moreover, patients with a higher Ki-67 index (&gt; cut-off point) showed significantly lower 5year-DFS/OS rates compared with those whose Ki-67 index were below cut-off point. In addition, Ki-67 index of post-NAC were independent prognostic factors for 5 year disease-free survival of patients with HR+/HER2- breast cancer. Ki-67 change between pre- and post-NAC as an independent prognostic factor independently predict prognosis in the patients who have not achieved pCR, while the best cut-off point was 18%.

Conclusion

The Ki-67 index of pre- and post-NAC could predict the prognosis in the patients with HER2- breast cancer. Moreover, the Ki-67 change between pre- and post-NAC was an independent prognostic factor in the patients who have not achieved pCR.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-08-05.

Growth promotion and colonization of switchgrass (Panicum virgatum) cv. Alamo by bacterial endophyte Burkholderia phytofirmans strain PsJN

BACKGROUND

Switchgrass is one of the most promising bioenergy crop candidates for the US. It gives relatively high biomass yield and can grow on marginal lands. However, its yields vary from year to year and from location to location. Thus it is imperative to develop a low input and sustainable switchgrass feedstock production system. One of the most feasible ways to increase biomass yields is to harness benefits of microbial endophytes.

RESULTS

We demonstrate that one of the most studied plant growth promoting bacterial endophytes, Burkholderia phytofirmans strain PsJN, is able to colonize and significantly promote growth of switchgrass cv. Alamo under in vitro, growth chamber, and greenhouse conditions. In several in vitro experiments, the average fresh weight of PsJN-inoculated plants was approximately 50% higher than non-inoculated plants. When one-month-old seedlings were grown in a growth chamber for 30 days, the PsJN-inoculated Alamo plants had significantly higher shoot and root biomass compared to controls. Biomass yield (dry weight) averaged from five experiments was 54.1% higher in the inoculated treatment compared to non-inoculated control. Similar results were obtained in greenhouse experiments with transplants grown in 4-gallon pots for two months. The inoculated plants exhibited more early tillers and persistent growth vigor with 48.6% higher biomass than controls. We also found that PsJN could significantly promote growth of switchgrass cv. Alamo under sub-optimal conditions. However, PsJN-mediated growth promotion in switchgrass is genotype specific.

CONCLUSIONS

Our results show B. phytofirmans strain PsJN significantly promotes growth of switchgrass cv. Alamo under different conditions, especially in the early growth stages leading to enhanced production of tillers. This phenomenon may benefit switchgrass establishment in the first year. Moreover, PsJN significantly stimulated growth of switchgrass cv. Alamo under sub-optimal conditions, indicating that the use of the beneficial bacterial endophytes may boost switchgrass growth on marginal lands and significantly contribute to the development of a low input and sustainable feedstock production system.

Acetylesterase-mediated deacetylation of pectin impairs cell elongation, pollen germination, and plant reproduction

Pectin is a major component of the primary cell wall of higher plants. Some galacturonyl residues in the backbone of pectinaceous polysaccharides are often O-acetylated at the C-2 or C-3 position, and the resulting acetylesters change dynamically during the growth and development of plants. The processes involve both enzymatic acetylation and deacetylation. Through genomic sequence analysis, we identified a pectin acetylesterase (PAE1) from black cottonwood (Populus trichocarpa). Recombinant Pt PAE1 exhibited preferential activity in releasing the acetate moiety from sugar beet (Beta vulgaris) and potato (Solanum tuberosum) pectin in vitro. Overexpressing Pt PAE1 in tobacco (Nicotiana tabacum) decreased the level of acetyl esters of pectin but not of xylan. Deacetylation engendered differential changes in the composition and/or structure of cell wall polysaccharides that subsequently impaired the cellular elongation of floral styles and filaments, the germination of pollen grains, and the growth of pollen tubes. Consequently, plants overexpressing PAE1 exhibited severe male sterility. Furthermore, in contrast to the conventional view, PAE1-mediated deacetylation substantially lowered the digestibility of pectin. Our data suggest that pectin acetylesterase functions as an important structural regulator in planta by modulating the precise status of pectin acetylation to affect the remodeling and physiochemical properties of the cell wall's polysaccharides, thereby affecting cell extensibility.

Delineation of VEGF-regulated genes and functions in the cervix of pregnant rodents by DNA microarray analysis

BACKGROUND

VEGF-regulated genes in the cervices of pregnant and non-pregnant rodents (rats and mice) were delineated by DNA microarray and Real Time PCR, after locally altering levels of or action of VEGF using VEGF agents, namely siRNA, VEGF receptor antagonist and mouse VEGF recombinant protein.

METHODS

Tissues were analyzed by genome-wide DNA microarray analysis, Real-time and gel-based PCR, and SEM, to decipher VEGF function during cervical remodeling. Data were analyzed by EASE score (microarray) and ANOVA (Real Time PCR) followed by Scheffe's F-test for multiple comparisons.

RESULTS

Of the 30,000 genes analyzed, about 4,200 genes were altered in expression by VEGF, i.e., expression of about 2,400 and 1,700 genes were down- and up-regulated, respectively. Based on EASE score, i.e., grouping of genes according to their biological process, cell component and molecular functions, a number of vascular- and non-vascular-related processes were found to be regulated by VEGF in the cervix, including immune response (including inflammatory), cell proliferation, protein kinase activity, and cell adhesion molecule activity. Of interest, mRNA levels of a select group of genes, known to or with potential to influence cervical remodeling were altered. For example, real time PCR analysis showed that levels of VCAM-1, a key molecule in leukocyte recruitment, endothelial adhesion, and subsequent trans-endothelial migration, were elevated about 10 folds by VEGF. Further, VEGF agents also altered mRNA levels of decorin, which is involved in cervical collagen fibrillogenesis, and expression of eNO, PLC and PKC mRNA, critical downstream mediators of VEGF. Of note, we show that VEGF may regulate cervical epithelial proliferation, as revealed by SEM.

CONCLUSION

These data are important in that they shed new insights in VEGF's possible roles and mechanisms in cervical events near-term, including cervical remodeling.

Functional analysis of the cellulose synthase-like genes CSLD1, CSLD2, and CSLD4 in tip-growing Arabidopsis cells

A reverse genetic approach was used to investigate the functions of three members of the cellulose synthase superfamily in Arabidopsis (Arabidopsis thaliana), CELLULOSE SYNTHASE-LIKE D1 (CSLD1), CSLD2, and CSLD4. CSLD2 is required for normal root hair growth but has a different role from that previously described for CSLD3 (KOJAK). CSLD2 is required during a later stage of hair development than CSLD3, and CSLD2 mutants produce root hairs with a range of abnormalities, with many root hairs rupturing late in development. Remarkably, though, it was often the case that in CSLD2 mutants, tip growth would resume after rupturing of root hairs. In silico, semiquantitative reverse transcription-polymerase chain reaction, and promoter-reporter construct analyses indicated that the expression of both CSLD2 and CSLD3 is elevated at reduced temperatures, and the phenotypes of mutants homozygous for insertions in these genes were partially rescued by reduced temperature growth. However, this was not the case for a double mutant homozygous for insertions in both CSLD2 and CSLD3, suggesting that there may be partial redundancy in the functions of these genes. Mutants in CSLD1 and CSLD4 had a defect in male transmission, and plants heterozygous for insertions in CSLD1 or CSLD4 were defective in their ability to produce pollen tubes, although the number and morphology of pollen grains was normal. We propose that the CSLD family of putative glycosyltransferases synthesize a polysaccharide that has a specialized structural role in the cell walls of tip-growing cells.

DISTINCT ROLES FOR DISCOIDIN DOMAIN RECEPTOR 1 (DDR1) EXPRESSED ON BONE MARROW DERIVED CELLS AND VESSEL WALL CELLS DURINGATHEROGENESIS

We have recently described a critical role for the discoidin domain receptor 1 (DDR1) collagen receptor tyrosine kinase in the regulation of fibrosis and inflammation during atherosclerotic plaque development. DDR1 isexpressed on both SMCs and macrophages; however the role of DDR1 expressed in these distinct cells during atherogenesis remains unresolved. In the current study, female Ldlr^-/- mice that were either Ddr1^+/+ or Ddr1^-/-were lethally irradiated and reconstituted with bone marrow from male Ddr1^+/+ or Ddr1^-/- donors yielding three groups of chimeric mice: Ddr1^+/+^?^+/+ (control); Ddr1^+/+^?^-/-^ (vessel wall deletion); and Ddr1^-/-^?^+/+ (bone marrow deletion). Chimeric mice were placed on an atherogenic diet for 12 weeks and hadsimilar body weights, total leukocyte counts, levels of Sry chimerism, and fasting plasma triglycerides at sacrifice, although total cholesterol was increased by 42% in Ddr1^+/+^?^-/- mice. Deletion of DDR1 inbone marrow derived cells (Ddr1^-/-^?^+/+) resulted in a 66% reduction in atherosclerotic lesion area in thedescending aorta compared to Ddr1^+/+^?^+/+ mice. Aortic sinus plaquesfrom Ddr1^-/-^?^+/+ mice were 36% smaller than Ddr1^+/+^?^+/+ plaques but the proportion of plaque area occupied by cells and matrix was similar between groups. By contrast, deletion of DDR1 in vessel wall cells (Ddr1^+/+^?^-/-) resulted in a 57% increase in atherosclerosis in the descending aorta. Furthermore, aortic sinus plaques from Ddr1^+/+ ^?^-/- mice had markedly increased fibrillar collagen and elastin accumulation compared to Ddr1^+/+^?^+/+ plaques resulting in a 156% increase in lesion area and reduced SMC and macrophage content. In conclusion, while DDR1 on bone marrow derived cells is required for plaque development, DDR1 expressed on vessel wall cells negatively regulates plaque matrix accumulation and results in the formation of larger lesions with altered cellular composition. Our data suggest a dual role for DDR1 in the regulationof atherogenesis and plaque matrix content.

The highly similar Arabidopsis homologs of trithorax ATX1 and ATX2 encode proteins with divergent biochemical functions

Gene duplication followed by functional specialization is a potent force in the evolution of biological diversity. A comparative study of two highly conserved duplicated genes, ARABIDOPSIS TRITHORAX-LIKE PROTEIN1 (ATX1) and ATX2, revealed features of both partial redundancy and of functional divergence. Although structurally similar, their regulatory sequences have diverged, resulting in distinct temporal and spatial patterns of expression of the ATX1 and ATX2 genes. We found that ATX2 methylates only a limited fraction of nucleosomes and that ATX1 and ATX2 influence the expression of largely nonoverlapping gene sets. Even when coregulating shared targets, ATX1 and ATX2 may employ different mechanisms. Most remarkable is the divergence of their biochemical activities: both proteins methylate K4 of histone H3, but while ATX1 trimethylates it, ATX2 dimethylates it. ATX2 and ATX1 provide an example of separated K4 di from K4 trimethyltransferase activity.

ABA, ROS and NO are Key Players During Switchgrass Seed Germination

Seed dormancy and germination are complex physiological processes usually under hormonal control. Germination of seeds from many plants including switchgrass, are inhibited by ABA and promoted by NO or ROS. However, ABA apparently requires both ROS and NO as intermediates in its action, with ROS produced by membrane-bound NADPH-oxidases responsive to ABA. In switchgrass seeds, externally supplied hydrogen peroxide (ROS), but not NO will overcome ABA-imposed inhibition of germination. Stimulation of germination by external ROS can be partially blocked by NO-scavengers, suggesting that NO is required for seed germination in switchgrass as well as for ABA-induced inhibition of germination. Collectively, these data suggest that multiple mechanisms might be required to sense and respond to varying levels of ABA, NO and ROS in switchgrass seeds.

Reactive oxygen species, ABA and nitric oxide interactions on the germination of warm-season C4-grasses

Hydrogen peroxide (H(2)O(2)) as a source of reactive oxygen species (ROS) significantly stimulated germination of switchgrass (Panicum virgatum L.) seeds with an optimal concentration of 20 mM at both 25 and 35 degrees C. For non-dormant switchgrass seeds exhibiting different levels of germination, treatment with H(2)O(2) resulted in rapid germination (<3 days) of all germinable seeds as compared to seeds placed on water. Exposure to 20 mM H(2)O(2) elicited simultaneous growth of the root and shoot system, resulting in more uniform seedling development. Seeds of big bluestem (Andropogon gerardii Vitman) and indiangrass [Sorghastrum nutans (L.) Nash] also responded positively to H(2)O(2) treatment, indicating the universality of the effect of H(2)O(2) on seed germination in warm-season prairie grasses. For switchgrass seeds, abscisic acid (ABA) and the NADPH-oxidase inhibitor, diphenyleneiodonium (DPI) at 20 microM retarded germination (radicle emergence), stunted root growth and partially inhibited NADPH-oxidase activity in seeds. H(2)O(2) reversed the inhibitory effects of DPI and ABA on germination and coleoptile elongation, but did not overcome DPI inhibition of root elongation. Treatment with H(2)O(2) appeared to enhance endogenous production of nitric oxide, and a scavenger of nitric oxide abolished the peroxide-responsive stimulation of switchgrass seed germination. The activities and levels of several proteins changed earlier in seeds imbibed on H(2)O(2) as compared to seeds maintained on water or on ABA. These data demonstrate that seed germination of warm-season grasses is significantly responsive to oxidative conditions and highlights the complex interplay between seed redox status, ABA, ROS and NO in this system.

Nitric oxide accelerates seed germination in warm-season grasses

The nitric oxide (NO) donor sodium nitroprusside (SNP) significantly promoted germination of switchgrass (Panicum virgatum L. cv Kanlow) in the light and in the dark at 25 degrees C, across a broad range of concentrations. SNP also promoted seed germination in two other warm-season grasses. A chemical scavenger of NO inhibited germination and blocked SNP stimulation of seed germination. The phenolic (+)-catechin acted synergistically with SNP and nitrite in promoting seed germination. Acidified nitrite, an alternate NO donor also significantly stimulated seed germination. Interestingly, sodium cyanide, potassium ferricyanide and potassium ferrocyanide at 200 microM strongly enhanced seed germination as well, whereas potassium chloride was without effect. Ferrocyanide and cyanide stimulation of seed germination was blocked by an NO scavenger. Incubation of seeds with a fluorescent NO-specific probe provided evidence for NO production in germinating switchgrass seeds. Abscisic acid (ABA) at 10 microM depressed germination, inhibited root elongation and essentially abolished coleoptile emergence. SNP partially overcame ABA effects on radicle emergence but did not overcome the effects of ABA on coleoptile elongation. Light microscopy indicated extension of the radicle and coleoptiles in seeds maintained on water or on SNP after 2 days. In contrast, there was minimal growth of the radicle and coleoptile in ABA-treated seeds even after 3-4 days. These data indicate that seed germination of warm-season grasses is significantly influenced by NO signaling pathways and document that NO could be an endogenous trigger for release from dormancy in these species.

Nitric oxide accelerates seed germination in warm-season grasses

The nitric oxide (NO) donor sodium nitroprusside (SNP) significantly promoted germination of switchgrass (Panicum virgatum L. cv Kanlow) in the light and in the dark at 25 degrees C, across a broad range of concentrations. SNP also promoted seed germination in two other warm-season grasses. A chemical scavenger of NO inhibited germination and blocked SNP stimulation of seed germination. The phenolic (+)-catechin acted synergistically with SNP and nitrite in promoting seed germination. Acidified nitrite, an alternate NO donor also significantly stimulated seed germination. Interestingly, sodium cyanide, potassium ferricyanide and potassium ferrocyanide at 200 microM strongly enhanced seed germination as well, whereas potassium chloride was without effect. Ferrocyanide and cyanide stimulation of seed germination was blocked by an NO scavenger. Incubation of seeds with a fluorescent NO-specific probe provided evidence for NO production in germinating switchgrass seeds. Abscisic acid (ABA) at 10 microM depressed germination, inhibited root elongation and essentially abolished coleoptile emergence. SNP partially overcame ABA effects on radicle emergence but did not overcome the effects of ABA on coleoptile elongation. Light microscopy indicated extension of the radicle and coleoptiles in seeds maintained on water or on SNP after 2 days. In contrast, there was minimal growth of the radicle and coleoptile in ABA-treated seeds even after 3-4 days. These data indicate that seed germination of warm-season grasses is significantly influenced by NO signaling pathways and document that NO could be an endogenous trigger for release from dormancy in these species.

RDR6 has a broad-spectrum but temperature-dependent antiviral defense role in Nicotiana benthamiana

SDE1/SGS2/RDR6, a putative RNA-dependent RNA polymerase (RdRP) from Arabidopsis thaliana, has previously been found to be indispensable for maintaining the posttranscriptional silencing of transgenes, but it is seemingly redundant for antiviral defense. To elucidate the antiviral role of this RdRP in a different host plant and to evaluate whether plant growth conditions affect its role, we down-regulated expression of the Nicotiana benthamiana homolog, NbRDR6, and examined the plants for altered susceptibility to various viruses at different growth temperatures. The results we describe here clearly show that plants with reduced expression of NbRDR6 were more susceptible to all viruses tested and that this effect was more pronounced at higher growth temperatures. Diminished expression of NbRDR6 also permitted efficient multiplication of tobacco mosaic virus in the shoot apices, leading to serious disruption with microRNA-mediated developmental regulation. Based on these results, we propose that NbRDR6 participates in the antiviral RNA silencing pathway that is stimulated by rising temperatures but suppressed by virus-encoded silencing suppressors. The relative strengths of these two factors, along with other plant defense components, critically influence the outcome of virus infections.

The promotion of gravitropism in Arabidopsis roots upon actin disruption is coupled with the extended alkalinization of the columella cytoplasm and a persistent lateral auxin gradient

The actin cytoskeleton has been implicated in regulating plant gravitropism. However, its precise role in this process remains uncertain. We have shown previously that disruption of the actin cytoskeleton with Latrunculin B (Lat B) strongly promoted gravitropism in maize roots. These effects were most evident on a clinostat as curvature that would exceed 90 degrees despite short periods of horizontal stimulation. To probe further the cellular mechanisms underlying these enhanced gravity responses, we extended our studies to roots of Arabidopsis. Similar to our observations in other plant species, Lat B enhanced the response of Arabidopsis roots to gravity. Lat B (100 nm) and a stimulation time of 5-10 min were sufficient to induce enhanced bending responses during clinorotation. Lat B (100 nm) disrupted the fine actin filament network in different regions of the root and altered the dynamics of amyloplasts in the columella but did not inhibit the gravity-induced alkalinization of the columella cytoplasm. However, the duration of the alkalinization response during continuous gravistimulation was extended in Lat B-treated roots. Indirect visualization of auxin redistribution using the DR5:beta-glucuronidase (DR5:GUS) auxin-responsive reporter showed that the enhanced curvature of Lat B-treated roots during clinorotation was accompanied by a persistent lateral auxin gradient. Blocking the gravity-induced alkalinization of the columella cytoplasm with caged protons reduced Lat B-induced curvature and the development of the lateral auxin gradient. Our data indicate that the actin cytoskeleton is unnecessary for the initial perception of gravity but likely acts to downregulate gravitropism by continuously resetting the gravitropic-signaling system.

Developmental anatomy and auxin response of lateral root formation in Ceratopteris richardii

The homosporous fern Ceratopteris richardii exhibits a homorhizic root system where roots originate from the shoot system. These shoot-borne roots form lateral roots (LRs) that arise from the endodermis adjacent to the xylem poles, which is in contrast to flowering plants where LR formation arises from cell division in the pericycle. A detailed study of the fifth shoot-borne root showed that one lateral root mother cell (LRMC) develops in each two out of three successive merophytes. As a result, LRs emerge alternately in two ranks from opposite positions on a parent root. From LRMC initiation to LR emergence, three developmental stages were identified based on anatomical criteria. The addition of auxins (either indole-3-acetic acid or indole-3-butyric acid) to the growth media did not induce additional LR formation, but exogenous applications of both auxins inhibited parent root growth rate. Application of the polar auxin-transport inhibitor N-(1-naphthyl)phthalamic acid (NPA) also inhibited parent root growth without changing the LR initiation pattern. The results suggest that LR formation does not depend on root growth rate per se. The result that exogenous auxins do not promote LR formation in C. richardii is similar to reports for certain species of flowering plants, in which there is an acropetal LR population and the formation of the LRs is insensitive to the application of auxins. It also may indicate that different mechanisms control LR development in non-seed vascular plants compared with angiosperms, taking into consideration the long and independent evolutionary history of the two groups.

Elevated levels of N-lauroylethanolamine, an endogenous constituent of desiccated seeds, disrupt normal root development in Arabidopsis thaliana seedlings

N-Acylethanolamines (NAEs) are prevalent in desiccated seeds of various plant species, and their levels decline substantially during seed imbibition and germination. Here, seeds of Arabidopsis thaliana (L.) Heynh. were germinated in, and seedlings maintained on, micromolar concentrations of N-lauroylethanolamine (NAE 12:0). NAE 12:0 inhibited root elongation, increased radial swelling of root tips, and reduced root hair numbers in a highly selective and concentration-dependent manner. These effects were reversible when seedlings were transferred to NAE-free medium. Older seedlings (14 days old) acclimated to exogenous NAE by increased formation of lateral roots, and generally, these lateral roots did not exhibit the severe symptoms observed in primary roots. Cells of NAE-treated primary roots were swollen and irregular in shape, and in many cases showed evidence, at the light- and electron-microscope levels, of improper cell wall formation. Microtubule arrangement was disrupted in severely distorted cells close to the root tip, and endoplasmic reticulum (ER)-localized green fluorescent protein (mGFP5-ER) was more abundant, aggregated and distributed differently in NAE-treated root cells, suggesting disruption of proper cell division, endomembrane organization and vesicle trafficking. These results suggest that NAE 12:0 likely influences normal cell expansion in roots by interfering with intracellular membrane trafficking to and/or from the cell surface. The rapid metabolism of NAEs during seed imbibition/germination may be a mechanism to remove this endogenous class of lipid mediators to allow for synchronized membrane reorganization associated with cell expansion.

Enhanced gravitropism of roots with a disrupted cap actin cytoskeleton

The actin cytoskeleton has been proposed to be a major player in plant gravitropism. However, understanding the role of actin in this process is far from complete. To address this problem, we conducted an analysis of the effect of Latrunculin B (Lat B), a potent actin-disrupting drug, on root gravitropism using various parameters that included detailed curvature kinetics, estimation of gravitropic sensitivity, and monitoring of curvature development after extended clinorotation. Lat B treatment resulted in a promotion of root curvature after a 90 degrees reorientation in three plant species tested. More significantly, the sensitivity of maize (Zea mays) roots to gravity was enhanced after actin disruption, as determined from a comparison of presentation time of Lat B-treated versus untreated roots. A short 10-min gravistimulus followed by extended rotation on a 1-rpm clinostat resulted in extensive gravitropic responses, manifested as curvature that often exceeded 90 degrees. Application of Lat B to the cap or elongation zone of maize roots resulted in the disruption of the actin cytoskeleton, which was confined to the area of localized Lat B application. Only roots with Lat B applied to the cap displayed the strong curvature responses after extended clinorotation. Our study demonstrates that disrupting the actin cytoskeleton in the cap leads to the persistence of a signal established by a previous gravistimulus. Therefore, actin could function in root gravitropism by providing a mechanism to regulate the proliferation of a gravitropic signal originating from the cap to allow the root to attain its correct orientation or set point angle.

Enhanced gravitropism of roots with a disrupted cap actin cytoskeleton

The actin cytoskeleton has been proposed to be a major player in plant gravitropism. However, understanding the role of actin in this process is far from complete. To address this problem, we conducted an analysis of the effect of Latrunculin B (Lat B), a potent actin-disrupting drug, on root gravitropism using various parameters that included detailed curvature kinetics, estimation of gravitropic sensitivity, and monitoring of curvature development after extended clinorotation. Lat B treatment resulted in a promotion of root curvature after a 90 degrees reorientation in three plant species tested. More significantly, the sensitivity of maize (Zea mays) roots to gravity was enhanced after actin disruption, as determined from a comparison of presentation time of Lat B-treated versus untreated roots. A short 10-min gravistimulus followed by extended rotation on a 1-rpm clinostat resulted in extensive gravitropic responses, manifested as curvature that often exceeded 90 degrees. Application of Lat B to the cap or elongation zone of maize roots resulted in the disruption of the actin cytoskeleton, which was confined to the area of localized Lat B application. Only roots with Lat B applied to the cap displayed the strong curvature responses after extended clinorotation. Our study demonstrates that disrupting the actin cytoskeleton in the cap leads to the persistence of a signal established by a previous gravistimulus. Therefore, actin could function in root gravitropism by providing a mechanism to regulate the proliferation of a gravitropic signal originating from the cap to allow the root to attain its correct orientation or set point angle.

Synthesis and thrombolytic activity of new thienopyrimidinone derivatives

It has been observed that ticlopidine and clopidogrel show, apart from their delayed antiplatelet properties, an immediate and transient thrombolytic action related to the ability of these thienopyridines to stimulate the secretory function of vascular endothelium. With the objective to construct new molecules with identical thrombolytic potency but at a higher level, we carried out different structural modifications in the thienopyridine chemical molecule to conclude that the presence of a second N atom in the pyridine cycle (yielding pyrimidine moiety) and the presence of an additional cycle fused to the thienyl ring would lead to enhanced thrombolytic effects. Here we report the six-step synthesis of a series of new benzothienopyrimidinone derivatives characterized by this searched for potent thrombolytic activity. The pharmacological assay used anaesthetised Wistar rats with extracorporal circulation in which arterial blood superfused thrombi adhering to a strip of collagen. Weight of thrombi was continuously monitored. Six compounds of the series were much more potent thrombolytic agents than their thienopyridine references: the effective thrombolytic dose that produced 30% of maximum thrombolysis (ED30) was at a range of 8 to 170 microg kg(-1) as compared with ED30 values of 16000 to 20000 microg kg(-1) for clopidogrel and ticlopidine respectively. Especially with the most active compound, this difference in the threshold thrombolytic dose, giving an intensity of action higher by three orders of magnitude, was accompanied by a lengthening of the response. Apart from that these compounds have shown to be synthetic thrombolytics, they certainly deserve further studying.

In vivo blockade of macrophage migration inhibitory factor prevents skin graft destruction after indirect allorecognition

BACKGROUND

The effector mechanisms that ultimately destroy transplanted tissues are poorly understood. In particular, it is not clear how CD4+ T cells primed to donor-derived determinants expressed on recipient MHC molecules (the indirect pathway) can mediate graft destruction in the absence of cognate recognition of peptide: MHC on the graft cells themselves. Macrophage migration inhibitory factor (MIF) inhibits macrophage movement and is a proinflammatory and regulatory cytokine known to be essential for development of delayed-type hypersensitivity reactions.

METHODS

To test whether MIF participates in graft destruction following indirect recognition, we studied rejection of MHC-II-deficient skin grafts placed on allogeneic SCID recipients adoptively transferred with naïve CD4+ T cells, and the recipients were treated with neutralizing anti-MIF monoclonal antibody or isotype control IgG. In this model graft rejection can only occur indirectly as the graft cells lack MHC II for recognition by the recipient CD4+ T cells.

RESULTS

We found that in vivo blockade of MIF inhibited indirect CD4+ cell-mediated skin graft destruction, and markedly reduced detectable macrophages within the grafts. The neutralizing anti-MIF antibody significantly inhibited alloreactive DTH but did not prevent T cell priming or interferon-gamma release by primed T cells.

CONCLUSIONS

The results strongly implicate MIF as an active participant in skin graft destruction after indirect recognition and suggest that this effect is mediated through an inhibition of macrophage migration and/or function.

[Influence of HLA class I molecules expression on tumor cell resistance to NK lysis and the IFN-gamma regulatory effect]

OBJECTIVE

To investigate the relation between the NK lysis and HLA molecules expressed on the target cells as well as the regulatory effect of IFN-gamma.

METHODS

The level of HLA-ABC molecules on seven human tumor cell lines were detected through the indirect immune fluorescence stain. NK lysis changes were observed after the blocking of HLA molecules on the target cells with the anti-HLA monoclonal antibodies or treating target cells with IFN-gamma.

RESULTS

1. Most of the tumor cell lines showed a complete or partial loss of HLA-ABC molecules, 2. After the HLA molecules had been marked on the target cells with the anti-HLA-ABC antibodies, the tumor cell susceptibility to the lysis of NK cells attack increased significantly and 3. After having being treated with IFN-gamma 500 U/ml for more than 48 hours, the HLA-ABC molecule levels on K562, M21 and PG cells went up. At the same time, their susceptibility to NK lysis was reduced. However, the resistance to Karpas, HL60 and HT29 NK lysis demonstrated a noticeable increase. The IFN-gamma promoted the apoptosis of HL60 and HT29 cells.

CONCLUSION

The NK cells are capable of recognizing the HLA molecules on the target cells and show no lysis in providing a negative signal with the KIRs, an effect which the anti-HLA monoclonal antibodies are able to eliminate. IFN-gamma can be applied to make up for the loss of HLA molecules on some of the tumor cells, it can also facilitate some of the tumor cells' apoptosis.

Oriental noodles

Oriental noodles have been consumed for thousands of years and remain an important part in the diet of many Asians. There is a wide variety of noodles in Asia with many local variations as result of differences in culture, climate, region and a host of other factors. In this article noodle classification, formulation, processing and evaluation are reviewed, with emphasis on eight major types. Wheat quality requirements, basic flour specifications, ingredient functions, and production variables are identified for different noodles. In the evaluation of flour for noodle making, three key quality attributes are considered: processability, noodle color and texture. Noodle process behavior is particularly important in the modern industrial production. Each noodle type has its own unique color and texture characteristics. Flour color, protein content, ash content, yellow pigment and polyphenol oxidase activity are important factors responsible for noodle color. Starch characteristics, protein content and quality play major roles in governing the texture of cooked noodles. However, the relative importance of starch and proteins varies considerably with noodle type. Starch pasting quality is the primary trait determining the eating quality of Japanese and Korean noodles that are characterized by soft and elastic texture, while protein quantity and strength are very important to Chinese-type noodles that require firm bite and chewy texture. Other factors such as ingredients added in the noodle formula and processing variables used during noodle preparation also affect the cooked noodle texture as well.

[A study of Wilson's disease gene encoded products and gene mutations]

OBJECTIVE

To investigate the pathogenesis of Wilson's disease(WD).

METHODS

Hepatocytes were isolated from WD patients' bioptic hepatic samples and cultured in vitro; WD proteins, the gene putative encoded products, were detected by SDS-PAGE in conjunction with Western blotting in liver samples of three patients and two controls. Their genomic DNAs were analyzed by means of direct DNA sequencing of WD gene (ATP7B) on exon 8.

RESULTS

The WD proteins lanes from two WD patients were found to be much weaker than that from the control, from which one WD patient was proven as heterozygote of 778 position CGG-->CTG(Arg778Leu) and 770 position CTC-->CTG change of ATP7B.

CONCLUSION

WD is highly heterogeneous in clinical manifestations and inheritance pattern. Abnormally expressed putative WD proteins in WD patients might be the results of ATP7B mutations, and the study of ATP7B products would help to probe into the pathogenesis of WD.

[A study of gene products encoded by Wilson disease gene]

OBJECTIVE

To investigate the pathogenesis of Wilson disease (WD) by detecting its gene products encoded by WD gene (ATP7B).

METHODS

Patients diagnosed as WD were analyzed by SDS-PAGE in conjunction with Western blot. Two antibodies were used, which are specially against the sixth copper binding domain (Anti-CuBD) and ATP binding domain (Anti-ABD) of WD protein.

RESULTS

The WD proteins were not expressed in two patients when using anti-CuBD, and poorly expressed when using anti-ABD.

CONCLUSIONS

WD is highly heterogeneous in clinical manifestations and inheritance pattern. Two WD patients might simultaneously have exon 5 mutations and exon 8 mutations. The study of WD gene products would probe into the pathogenesis of WD.

The discoidin domain receptor tyrosine kinase DDR1 in arterial wound repair

Collagens act as important signaling molecules regulating vascular smooth muscle cell responses during arterial wound repair. Discoidin domain receptors (DDRs) are a novel class of receptor tyrosine kinases that bind to several collagens and stimulate matrix metalloproteinase (MMP) production, but little is known about their expression and function in the vasculature. We posited a critical role for the DDRs controlling smooth muscle cell migration and proliferation and thus repair following arterial injury. Smooth muscle cells were isolated from the aortas of mice with a targeted deletion of the DDR1 gene (DDR1-null) and studied in culture using models that mimic critical steps in neointimal thickening. Our studies suggest that DDR1 plays an important role in regulating attachment to collagen, chemotaxis, proliferation, and MMP production in smooth muscle cells. Following mechanical injury to the carotid arteries, cross-sectional area of the neointima was significantly lower in DDR1-null mice than in wild-type mice. There was also a significant decrease in collagen deposition in the injured arteries of the DDR1-null mice. Our results support the hypothesis that DDR1 plays an important role as a collagen receptor, mediating intimal thickening after vascular injury.

[Using fluorescence PCR analysis for early diagnosis and carriers detection of Chinese Wilson's disease]

OBJECTIVE

To diagnose the pre-symptomatic cases of Chinese Wilson's disease(WD) and detect the potential carriers by using fluorescence PCR technique.

METHODS

Screening the high frequency spot Arg778Leu of WD gene mutation in 66 Chinese WD patients, 55 healthy family members and 30 controls, and selecting 3 random samples (2 from WD patients, 1 from controls) for DNA sequencing to testify the accuracy of fluorescence PCR.

RESULTS

Among 66 Chinese WD cases, 5 were found homozygous for mutation of Arg778Leu and 21 were compound heterozygous; the gene mutation rate was totally 39.4%. Out of 55 healthy family members, 12 were found heterozygous, and it was confirmed that 11 of these 12 individuals were WD gene carriers but not pre-symptomatic patients. The results of direct DNA sequencing consisted with those results detected by fluorescence PCR.

CONCLUSION

The Arg778Leu mutation in exon 8 is the high frequency spot of Chinese Wilson's disease gene. Fluorescence PCR analysis is a rapid, accurate gene diagnostic method and demonstrates a high detecting rate.

[ABO genotyping by PCR-direct sequencing method]

OBJECTIVE

To analyze the sequence difference between human A, B, and O alleles and establish the method of ABO genotyping by PCR direct sequencing.

METHODS

PCR-direct sequencing technique was used to analyze two regions of cDNA from A transferase gene, 233-433 and 660-788.

RESULTS

Two nucleotide substitutions at 258th and 297th were found in 233-433 region, and a nucleotide substitution at 700th was found in 660-788 region. At 258th, the nucleotide was guanine in A and B alleles, and adenine in O allele. At 297th, the nucleotide was adenine in A allele, and guanine in B allele. As this position, O allele was subdivided into two types, O(A) and O(G). At 700th, the nucleotide was guanine in A and O alleles, and adenine in B allele. Therefore, 8 genotypes, AA, AO(A), AB, BB, BO(G), O(A) O(A), O(G) O(G) and O(A) O(G), could be clearly determined by only analyzing the 233-433 region. The other two genotypes, AO(G) and BO(A), could be further distinguished by analyzing the 660-788 region.

CONCLUSION

The technique of PCR-direct sequencing provides an effective and new method for ABO genotyping further.

Thrombolysis by thienopyridines and their congeners

We propose that anti-platelet thienopyridines, such as ticlopidine or clopidogrel, are thrombolytic owing to endothelial release of prostacyclin (PGI2) and tissue plasminogen activator (t-PA). In this study we used anaesthetised Wistar rats with extracorporal circulation in which arterial blood superfused thrombi which adhered to a strip of collagen. Weight of thrombi was continuously monitored. When administered intravenously, clopidogrel or its R enantiomer deprived of anti-platelet action, both at doses of 3 mg x kg(-1), produced lost in weight of thrombi by 14.1 +/- 1.3% or 16.0 +/- 1.4% (n = 9), and at doses 10 mg x kg(-1) by 28.3 +/- 2.3% or 30.4 +/- 1.9% (n = 8), respectively. Maximum of thrombolysis occurred 30-45 min following the drug administration. Ticlopidine at a dose of 30 mg x kg(-1) reduced weight of thrombi by 33.7 +/- 1.7% (n = 32). Thrombolytic action of ticlopidine was accompanied by a rise in 6!keto-PGF1alpha blood levels from 0.42 +/- 0.10 to 1.58 +/- 0.29 ng x ml(-1) and t-PA antigen plasma levels from 4.70 +/- 1.00 to 12.90 +/- 1.15 ng x ml(-1) (n = 7). Five out of eleven tested thienopyridine congeners with pyrimidine or pyrimidinone instead of pyridine rings had thrombolytic potencies similar to that of clopidogrel (ED30s at a range of 6.2-11.4 mg x kg(-1)). A substantial increase in thrombolytic potency (ED30s at a range of 0.3-2.1 mg x kg(-1)) was observed for congeners in which thienyl ring was condensed with an additional cyclopentyl, cyclohexyl or cycloheptyl structures or in which thienopyridine complex was replaced for a pyridopyrimidine one. We claim that thienopyridines, independently of their delayed anti-platelet action, do produce immediate thrombolysis in vivo. This new activity emulates capacity of their native, non-metabolised molecules to release prostacyclin and tissue plasminogen activator. We have also shown that structural changes in molecules of thienopyridines may intensify their thrombolytic potency.

The analgesic action of semen coicis on severe functional dysmenorrhea--a sequential trial observation

The analgesic effect of Semen Coicis was observed with the sequential trial in 26 cases of severe functional dysmenorrhea. The results showed that the markedly effective rate was 90%, which was much better than that of the control group treated by indomethacin plus subcutaneous injection of atropine (P < or = 0.01).

A role for hyaluronan in macrophage accumulation and collagen deposition after bleomycin-induced lung injury

Elevated concentrations of hyaluronan (HA) are associated with the accumulation of macrophages in the lung after injury. We have investigated the role of HA in the inflammatory and fibrotic responses to lung injury using the intratracheal instillation of bleomycin in rats as a model. After bleomycin-induced lung injury, both HA content in bronchoalveolar lavage (BAL) and staining for HA in macrophages accumulating in injured areas of the lung were maximal at 4 d. Increased HA in BAL correlated with increased locomotion of isolated alveolar macrophages. HA-binding peptide was able to specifically block macrophage motility in vitro. Importantly, systemic administration of HA-binding peptide to rats before injury not only decreased alveolar macrophage motility and accumulation in the lung, but also reduced lung collagen alpha (I) messenger RNA and hydroxyproline contents. We propose a model in which HA plays a critical role in the inflammatory response and fibrotic consequences of acute lung injury.

Type VIII collagen stimulates smooth muscle cell migration and matrix metalloproteinase synthesis after arterial injury

Type VIII collagen is a matrix protein expressed in a number of tissues undergoing active remodeling, including injured arteries during neointimal formation and in human atherosclerotic plaques; however, very little is known about its function. We have investigated whether the type VIII collagen stimulates smooth muscle cell (SMC) migration and invasion by binding to integrin receptors and up-regulating matrix metalloproteinase (MMP) production. SMCs attached to plates coated with type VIII collagen in a dose-dependent manner, with maximal attachment occurring with coating solutions containing 25 microgram/ml collagen. Type VIII collagen at 100 microgram/ml stimulated an 83-fold increase in the migration of SMCs in a chemotaxis chamber. Antibodies against beta1 integrin receptors prevented attachment and migration of SMCs. Antibodies against alpha1 or alpha2 integrins reduced attachment of SMCs to type VIII collagen by 29% and 77%, respectively. We found that SMCs grown from the rat neointima, but not medial SMCs, increased their production of MMP-2 and -9 on adherence to type VIII collagen. This suggests that there is an important difference in phenotype between intimal and medial SMCs and that intimal SMCs have distinct matrix-dependent signaling mechanisms. Our findings suggest that type VIII collagen deposited in vascular lesions functions to promote SMC attachment and chemotaxis, and signals through integrin receptors to stimulate MMP synthesis, all of which are important mechanisms used in cell migration and invasion.

[The application of minisatellite MS31A MVR-PCR digital coding technique in forensic science]

Using isotope incorporate amplification technique of special 31A, 31A-A, 31A-G primers and alpha-32PdCTP, the minisatellite MS31A (located at D7S21 loci) was studied. A rapid, simple, and accurate MVR-PCR technique was successfully established. The technique can be applied in individual identification minutes amples, such as blood stains, semen stains contaminated by vaginal fluid, hair and bones. The sensitivity analysis revealed that this technique could detect 1 ng genoma DNA. It is also discribed about the application of the method in 40 criminal cases of rape and murder.

Evidence that NMDA receptors mediate the responses of putative RVLM presympathetic neurons to vagal afferent stimulation in rats

Experiments were performed in 25 urethane-anaesthetized male Sprague-Dawley rats. Forty-six RVLM neurons were identified as putative presympathetic neurons according to their arterial baroreceptor reflex related properties, i.e. they were inhibited by stimulation of the aortic nerve; silenced by elevation of blood pressure and had a cardiac cycle related rhythm of spontaneous discharge. Responses of these neurons to tripled square wave stimulation of vagal afferents was tested by means of peristimulus time histograms. In addition to a long-lasting inhibition (I2), some neurons had one (P0) or two excitatory peaks (P1 and P2), and there was a short-lasting inhibition (I1) between P1 and P2. After microinjection of CPP (0.1 microl, 50 mM) into the NTS, the inhibitory responses were blocked, but the excitatory peaks were not affected; in the CVLM, CPP microinjection of the same dose had a similar effect on the responses elicited by vagal afferent stimulation in 15 of the 24 neurons tested. No detectable effects were observed in 9 neurons. However, intravenously administered ketamine attenuated or abolished these responses, either inhibitory or excitatory, in a dose dependent way. These results suggest: (1) an NMDA mechanism is involved in both the inhibitory and the excitatory responses. For the inhibitory responses, the involvement is both in the NTS and in the CVLM; for the excitatory responses, it is probably in the RVLM. (2) There may be a direct excitatory amino acid (EAA) pathway from the NTS to the RVLM.