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Durán I, Salazar R, Casanovas O, Arrazubi V, Vilar E, Siu LL, Yao J, Tabernero J. New drug development in digestive neuroendocrine tumors. Ann Oncol 2007; 18:1307-13. [PMID: 17301070 DOI: 10.1093/annonc/mdm009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The traditional cytotoxic agents are of limited efficacy in the treatment of neuroendocrine tumors of the gastrointestinal tract (NETs). Recent investigations have brought up a number of biological features in this family of neoplasms that could represent targets for anticancer treatment. NETs seem to have an extraordinary tumor vascularization with high expression of proangiogenic molecules such as the vascular endothelial growth factor along with overexpression of certain tyrosine kinase receptors such as the epidermal growth factor receptor (EGFR), the insulin growth factor receptor (IGFR) and their downstream signaling pathway components (PI3K-AKT-mTOR). The rationale of an antiangiogenic approach in the treatment of NETs and the use of other pharmacological strategies such as EGFR, IGFR and mammalian target of rapamycin inhibitors are discussed. Additionally, the emerging results of recent clinical trials with these targeted drugs are presented.
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Wang J, Liu J, Chen H, Yao J. Characterization of Fusarium graminearum inhibitory lipopeptide from Bacillus subtilis IB. Appl Microbiol Biotechnol 2007; 76:889-94. [PMID: 17611753 DOI: 10.1007/s00253-007-1054-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2006] [Revised: 05/24/2007] [Accepted: 05/25/2007] [Indexed: 11/25/2022]
Abstract
Bacillus subtilis strain IB exhibiting inhibitory activity against the Fusarium head blight disease fungus Fusarium graminearum was isolated and identified. The major inhibitory compound was purified from the culture broth through anion exchange, hydrophobic interaction, and reverse phase high-performance liquid chromatography (RP-HPLC) steps. It was a 1,463-Da lipopeptide and had an amino acid composition consisting of Ala, Glx, Ile, Orn, Pro, Thr, and Tyr at a molar ratio of 1:3:1:1:1:1:2. Electrospray ionization mass spectrometry/mass spectrometry (ESI MS/MS) analyses of the natural and the ring-opened peptides showed the antagonist was fengycin, a kind of macrolactone molecule with antifungal activity produced by several Bacillus strains. Fluorescence microscopic analysis indicated this peptide permeabilized and disrupted F. graminearum hyphae.
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Tan D, Yao J, Javle M, Law A, Brown R. Morphoproteomic depiction of constitutively activated mTOR and ERK pathways in adenocarcinoma of the large intestine: A pilot study. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.14580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
14580 Background: Preclinical studies have demonstrated a role for the mammalian target of rapamycin (mTOR) pathway in intestinal tumorigenesis. However, the mTOR and its related ERK pathway in human adenocarcinoma of the large intestine (ALI) have been little examined. Methods: To assess morphoproteomic alterations of ALI, tissue materials from three patients with ALI were analyzed in the present study. Antibody probes used included phosphorylated (p)-mTOR (Ser-2448) and one of its downstream effectors, p-p70S6K (Thr-389); bcl-2, which undergoes mTOR-dependent phosphorylative inactivation; and p-extracellular signal-regulated kinase (ERK)1/2 (Thr-202/Tyr-204), a co-activator of p-p70S6K. The intensity of the chromogenic signal and the cellular compartmentalization (plasmalemmal, cytoplasmic, and/or nuclear) were assessed and scored on a scale of 0–3+. Results: Moderate to strong (up to 2+ or 3+) expression of p-mTOR and its substrate, p-p70S6K, and p-ERK1/2 was present in all three cases. We also found plasmalemmal translocation of p-mTOR and nuclear translocation of p-p70S6K and p-ERK1/2, indicating constitutive activation of these protein analytes and their corresponding signal transduction pathways. We did not detect bcl-2 expression in any of these cases. Conclusions: Morphoproteomic analysis reveals constitutive activation of the mTOR and ERK pathways in ALI as evidenced by the collective commonalities of expression of p-mTOR, p-p70S6K, and p- ERK1/2 and the plasmalemmal translocation of p-mTOR and nuclear translocation of p-p70S6K and p-ERK1/2. The absence of bcl-2 expression in this context is noteworthy. These findings coincide with the preclinical data on the efficacy of rapamycin and a rapamycin analogue against colon cancer cell lines and xenograft models. Although preliminary, these observations of morphoproteomic alterations represent the first in primary human ALI specimens according to a review of the literature. The present pilot study offers a starting point for further studies (we are currently conducting a confirmatory study with larger series of cases) and the design of clinical trials using such small molecule inhibitors(e.g. rapamycin, RAD001) in a combinational strategy against ALI. No significant financial relationships to disclose.
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Eng-Wong J, Chow CK, Orzano J, Venzon D, Zujewski J, Yao J, Prindiville S. The effect of raloxifene on breast MRI volume in premenopausal women at increased risk for invasive breast cancer. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.1518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
1518 Background: Breast MRI volume (MRIV) and mammographic density (MD) assess the amount of fibroglandular tissue in the breast. While increased MD is associated with a 4 to 6 fold increase in breast cancer risk, the association between MRIV and breast cancer is unknown. Previous studies have shown that MRIV and MD can be modulated with hormonal interventions. We evaluated the effect of raloxifene on MRIV in premenopausal women at increased risk for breast cancer. We have previously reported that raloxifene did not change MD in this cohort. Raloxifene is indicated for the prevention and treatment of osteoporosis but not for prevention of breast cancer or for use in premenopausal women. Methods: Premenopausal women at increased risk by virtue of: Gail model risk > 1.7% over 5 years; lobular neoplasia, ductal carcinoma in situ, BRCA1/2 mutation positive, or a very strong family history were eligible for this phase II chemoprevention study. MRIs obtained at baseline and after two years on raloxifene 60 mg daily, and one year after discontinuing the drug were evaluated.T1 weighted spoiled gradient-echo MRI with fat suppression was used to determine volume using a semiautomatic method, after visual verification. Median relative change in MRIV was assessed by the Wilcoxon signed rank test. Results: 19 of 30 subjects who started study drug had breast MRI at baseline and after 2 years on raloxifene; median relative change was -16% (range -57 to +25%) (p=0.0004). 17 subjects had MRI at year 2 and one year after stopping drug. No significant change in MRIV was observed after stopping raloxifene, median relative change -9% (p=0.64). Conclusions: MRIV significantly declined while on raloxifene. In contrast no significant change in percent mammographic density in this same cohort was seen. Our findings suggest that MRIV may be a better surrogate biomarker than MD in premenopausal women at risk for breast cancer because of less variation in its measurement. MRIV should be further evaluated as a potential surrogate biomarker in prevention studies. No significant financial relationships to disclose.
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Hu G, Yao J, Quan H, Chen W. SU-FF-J-39: A Comparison of Two Methods Extracting Respiratory Information From Ultrasound Video. Med Phys 2007. [DOI: 10.1118/1.2760544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Yokouchi M, Hiramatsu N, Hayakawa K, Kasai A, Takano Y, Yao J, Kitamura M. Atypical, bidirectional regulation of cadmium-induced apoptosis via distinct signaling of unfolded protein response. Cell Death Differ 2007; 14:1467-74. [PMID: 17464326 DOI: 10.1038/sj.cdd.4402154] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Cadmium is a widely distributed nephrotoxic metal that causes renal tubular injury. In this report, we investigated involvement of endoplasmic reticulum (ER) stress and individual unfolded protein responses in cadmium-initiated apoptosis of tubular epithelial cells. Cadmium chloride (CdCl(2)) induced expression of endogenous ER stress markers, GRP78, GRP94 and CHOP in vitro and in vivo, and subsequently caused cytological changes typical of apoptosis. Attenuation of ER stress by transfection with ER chaperone GRP78 or ORP150 suppressed CdCl(2)-triggered apoptosis. In response to CdCl(2), phosphorylation of RNA-dependent protein kinase-like ER kinase (PERK) and eukaryotic translation initiation factor 2alpha (eIF2alpha) was observed. Enhanced phosphorylation of eIF2alpha attenuated, whereas inhibition of eIF2alpha exacerbated CdCl(2)-induced apoptosis. Activating transcription factor 6 (ATF6) was also activated by CdCl(2) and blockade of this process suppressed induction of CHOP and thereby improved cell survival. CdCl(2) also triggered activation of the inositol-requiring ER-to-nucleus signal kinase 1 (IRE1)-X-box-binding protein 1 (XBP1) pathway and inhibition of XBP1 attenuated apoptosis independent of GRP78 and CHOP. c-Jun N-terminal kinase (JNK), another molecule downstream of IRE1, was also phosphorylated by CdCl(2) and its inhibition attenuated apoptosis. These results evidenced bidirectional regulation of apoptosis in cadmium-exposed cells. The ATF6 and IRE1 pathways cooperatively caused apoptosis via induction of CHOP, activation of XBP1 and phosphorylation of JNK, and the PERK-eIF2alpha pathway counteracted the proapoptotic processes.
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Yao J, Zhu Y, Sun W, Sawada N, Hiramatsu N, Takeda M, Kitamura M. Irsogladine maleate potentiates the effects of nitric oxide on activation of cAMP signalling pathways and suppression of mesangial cell mitogenesis. Br J Pharmacol 2007; 151:457-66. [PMID: 17435794 PMCID: PMC2013962 DOI: 10.1038/sj.bjp.0707255] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND AND PURPOSE Deficiency in nitric oxide (NO) is a major factor leading to deterioration and progression of certain glomerular diseases. Agents enhancing NO availability and potentiality are renoprotective. Irsogladine maleate (IM), an anti-ulcer drug, is reported to improve gastric blood flow via NO-dependent mechanisms. We, therefore, asked whether and how IM interacted with NO on glomerular mesangial cells. EXPERIMENTAL APPROACH Mesangial cells were exposed to IM and NO donors. Activation of cAMP signalling pathways was assessed by intracellular cAMP, phosphorylation of VASP, activation of the cAMP response element (CRE) and expression of CRE-regulated proteins. KEY RESULTS IM alone did not affect cell proliferation. However, it greatly enhanced the growth-inhibitory effect of NO donor S-nitroso-N-acetylpenicillamine (SNAP). IM acted synergistically with NO on suppression of mitogen-activated protein kinase activation, induction of gap junction protein connexin43, increase of intracellular cAMP, and phosphorylation of VASP. With the use of the CRE-SEAP-based reporting system, IM and SNAP cooperatively activated cAMP response elements (CRE). A similar activation of cAMP was induced by IM with two different NO donors, the sGC activator Bay 41-2272 and the cGMP analogue 8-bromo-cGMP. The effects of SNAP and IM on cAMP activation were mimicked by phosphodiesterase 3 (PDE3) and PDE4 inhibitors. In addition, IM markedly augmented cytokine-induced expression of iNOS, production of NO and activation of CRE. CONCLUSION AND IMPLICATIONS The effects of NO were greatly potentiated by IM through synergistic activation of cAMP pathway. Combined therapy with IM and NO may be developed for certain renal diseases.
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Yao J, Zhang J, Hou JF. Effects of Ipriflavone on Caged Layer Bone Metabolism In Vitro and In Vivo. Poult Sci 2007; 86:503-7. [PMID: 17297162 DOI: 10.1093/ps/86.3.503] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The effects of ipriflavone on caged layer bone metabolism were examined in vitro and in vivo. Ipriflavone at 10(-8) M stimulated the activity of osteoblasts cultured from embryonic chick calvariae, and 10(-9) to 10(-7) M inhibited osteoclasts from chick tibias and humeri. Ipriflavone concentrations of 10(-4) and 10(-5) M inhibited osteoblast activity. These results suggest that ipriflavone influences bone metabolism by regulating the functional balance between osteoblasts and osteoclasts. Based on these in vitro experiments, in vivo studies were conducted to further clarify the effects of ipriflavone. Five hundred 58-wk-old ISA caged layers were divided into 5 groups that were fed diets containing 0, 15, 25, 50, and 100 ppm of ipriflavone. The experiment lasted 70 d. Egg production increased in hens fed 25 ppm and decreased in hens fed 50 and 100 ppm when compared with the controls and hens fed 15 ppm (P < 0.05). Egg weight, shell quality, BW, and serum P, Ca, estrogen, and bone mineral content were not affected by inclusion of ipriflavone in the diet. Hens consuming 25 ppm of ipriflavone had greater serum alkaline phosphatase and bone gla-protein levels than controls. Adding 25 ppm of ipriflavone to the feed appears to be close to an ideal level for clinical treatment of osteoporosis because of improved egg production while maintaining bone mineral content.
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Hardy CL, O'Connor AE, Yao J, Sebire K, de Kretser DM, Rolland JM, Anderson GP, Phillips DJ, O'Hehir RE. Follistatin is a candidate endogenous negative regulator of activin A in experimental allergic asthma. Clin Exp Allergy 2007; 36:941-50. [PMID: 16839410 DOI: 10.1111/j.1365-2222.2006.02523.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Activin A is a member of the transforming growth factor-beta superfamily which is directly implicated in airway structural change and inflammation in asthma. In vitro, the biological effects of activin A are neutralized by the soluble binding protein follistatin. OBJECTIVE To determine the potential of endogenous follistatin to suppress activin A in vivo by analysing their relative tissue and kinetic compartmentalization during the effector phase of subchronic Th2-driven mucosal inflammation in a murine model of allergic asthma. METHODS Eosinophilic mucosal inflammation was elicited by triggering Th2 recall responses by antigen challenge in ovalbumin-sensitized BALB/c mice. The kinetics and distribution of activin A and follistatin protein were assessed in lung tissue and bronchoalveolar lavage fluid and measured in relation to airway eosinophilia, goblet cell metaplasia and Th2 cytokine production in mediastinal lymph nodes. RESULTS Follistatin was released concurrently with activin A suggesting it acts as an endogenous regulator: peak BAL concentrations coincided with maximal airway eosinophilia, and frequency of IL-4, IL-5 and IL-13 producing cells in mediastinal lymph nodes but induction lagged behind the onset of inflammation. Follistatin and activin A immunoreactivity were lost in airway epithelial cells in parallel with goblet cell metaplasia. Exogenous follistatin inhibited the allergen-specific Th2 immune response in mediastinal lymph nodes and mucus production in the lung. CONCLUSION Follistatin is preformed in the normal lung and released in concert with activin A suggesting it serves as an endogenous regulator. Disturbance of the fine balance between activin A and its endogenous inhibitor follistatin may be a determinant of the severity of allergic inflammation or tissue phenotypic shift in asthma.
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Yao J, Duan L, Fan M, Yuan J, Wu X. Notch1 induces cell cycle arrest and apoptosis in human cervical cancer cells: involvement of nuclear factor kappa B inhibition. Int J Gynecol Cancer 2007; 17:502-10. [PMID: 17316355 DOI: 10.1111/j.1525-1438.2007.00872.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Notch signaling can serve as a tumor suppressor or tumor promoter in the same kind of cancer, such as human papillomavirus-positive cervical cancer cells. However, the exact mechanisms remain poorly characterized. Our studies demonstrated that constitutively overexpressed active Notch1 via stable transfection with exogenous intracellular domain of Notch1 (ICN) resulted in growth inhibition of the human cervical cancer cell line HeLa by inducing G(2)-M arrest and apoptosis. Moreover, the growth inhibition was correlated with inhibition of nuclear factor kappa B (NF-kappaB) p50 activation, accompanied by a decrease in the nuclear expression of NF-kappaB p50 and an increase in the cytosolic expression of IkappaBalpha. Consistent with these results, downregulation of cyclin D1 and Bcl-2, which are both the downstream genes of NF-kappaB, were observed in ICN-overexpressed cells. Overall, our results suggest that NF-kappaB inhibition may contribute partially to cell cycle arrest and apoptosis induced by Notch1 activation in human cervical cancer cells.
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Zhou J, Yao J, Deng J, Dewald J. EEG-based Discrimination of Elbow/Shoulder Torques using Brain Computer Interface Algorithms: Implications for Rehabilitation. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:4134-7. [PMID: 17281143 DOI: 10.1109/iembs.2005.1615373] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Brain computer interface (BCI) algorithms are used to predict the torque generation in the direction of shoulder abduction or elbow flexion using scalp EEG signals from 163 electrodes. Based on features extracted from both frequency and time domains, three classifiers are employed including support vector classifier, classification trees and K nearest neighbor. Support vector classifier achieves the highest recognition rate of 92.9% on two able-bodied subjects in average. The recognition rates we obtained on the able-bodied subjects are among the highest compared with previous reports on predicting motor intent using scalp EEG. This demonstrates the feasibility of separating the shoulder/elbow torques using scalp EEG as well as the potential of support vector classifier in applications of BCI. Preliminary experiments on two hemiparetic stroke subjects using support vector classifier reports an accuracy of 84.1% in average, which shows an increased difficulty in predicting intent presumably due to cortical reorganization resulting from the stroke.
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Lebak JW, Yao J, Warren S. HL7-compliant healthcare information system for home monitoring. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2004:3338-41. [PMID: 17270997 DOI: 10.1109/iembs.2004.1403938] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A secure, home-to-remote database communication hierarchy using Health Level Seven (HL7) has been developed. Measurements acquired from the patient via a wireless, wearable monitoring system are inserted into a local database using LabVIEW. Periodically, the HL7 client securely updates the remote database with information from the local database. HL7 communications are performed by Interfaceware's Chameleon software. Using Chameleon's flexible interface, doctors and researchers may access these patient data securely, confidentially, and remotely.
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Coulibaly I, Danzmann RG, Palti Y, Vallejo R, Gahr SA, Yao J, Rexroad CE. Mapping of genes in a region associated with upper temperature tolerance in rainbow trout. Anim Genet 2007; 37:598-9. [PMID: 17121611 DOI: 10.1111/j.1365-2052.2006.01529.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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314
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Zhu Q, Wani G, Yao J, Patnaik S, Wang QE, El-Mahdy MA, Praetorius-Ibba M, Wani AA. The ubiquitin–proteasome system regulates p53-mediated transcription at p21waf1 promoter. Oncogene 2007; 26:4199-208. [PMID: 17224908 DOI: 10.1038/sj.onc.1210191] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The ubiquitin (Ub)-proteasome system (UPS) promotes the proteasomal degradation of target proteins by decorating them with Ub labels. Emerging evidence indicates a role of UPS in regulating gene transcription. In this study, we provided evidence for the involvement of UPS in the transcriptional activation function of tumor suppressor p53. We showed that both ubiquitylation and proteasomal functions are required for efficient transcription mediated by p53. Disruption of transcription by actinomycin D, 5,6-dichloro-1-beta-D-ribofuranosyl-benzimadazole or alpha-amanitin leads to accumulation of cellular p53 protein. Proteasome inhibition by MG132 increases the occupancy of p53 protein at p53-responsive p21(waf1) promoter. In addition, the Sug-1 component of 19S proteasome physically interacts with p53 in vitro and in vivo. Moreover, in response to ultraviolet-induced DNA damage, both the 19S proteasomal components, Sug1 and S1, are recruited to p21(waf1) promoter region in a kinetic pattern similar to that of p53. These results suggested that UPS positively regulates p53-mediated transcription at p21(waf1) promoter.
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Moulu JC, Kalaydjian F, Tsakiroglou CD, Burganos VN, Payatakes AC, Yao J, Thovert JF, Adler PM. Characterization, Reconstruction and Transport Properties of Vosges Sandstones. ACTA ACUST UNITED AC 2006. [DOI: 10.2516/ogst:1997001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Kawamura K, Okada S, Li B, Suwa M, Yao J, Morioka T, Gejyo F, Oite T. Turbulence of glomerular hemodynamics involved in progressive glomerulosclerosis. Kidney Int 2006; 69:1792-8. [PMID: 16598199 DOI: 10.1038/sj.ki.5000350] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
There is increasing evidence that changes of glomerular hemodynamics or glomerular growth responses may promote the development of glomerulosclerosis. Major problems retarding research progress include lack of suitable experimental animal models, with the exception of the ablation model, and the need for in vivo real-time analysis of glomerular hemodynamics. This study examined the sequence of pathological changes from the viewpoints of microcirculation and histopathology, from the acute stage to the chronic course and the final stage of glomerulosclerosis, using the confocal laser scanning microscope system. There is a marked difference in prognosis between sham-operated (two-kidney) and nephrectomized (one-kidney) rats after injection with anti-Thy-1 antibody. The former reversibly returns to normal and the latter irreversibly go to progressive sclerosis, respectively. The turning point determining the progression of glomerulosclerosis in both groups seemed to be the period from 7 to 14 days after disease induction, when disturbance of local intraglomerular blood flow continued in the one-kidney groups. In conclusion, this study provides the first hemodynamic-based evidence showing that disturbance of intraglomerular microcirculation is a critical marker for progressive glomerulosclerosis.
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Hajdok G, Yao J, Battista JJ, Cunningham IA. Signal and noise transfer properties of photoelectric interactions in diagnostic x-ray imaging detectors. Med Phys 2006; 33:3601-20. [PMID: 17089826 DOI: 10.1118/1.2336507] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Image quality in diagnostic x-ray imaging is ultimately limited by the statistical properties governing how, and where, x-ray energy is deposited in a detector. This in turn depends on the physics of the underlying x-ray interactions. In the diagnostic energy range (10-100 keV), most of the energy deposited in a detector is through photoelectric interactions. We present a theoretical model of the photoelectric effect that specifically addresses the statistical nature of energy absorption by photoelectrons, K and L characteristic x rays, and Auger electrons. A cascaded-systems approach is used that employs a complex structure of parallel cascades to describe signal and noise transfer through the photoelectric effect in terms of the modulation transfer function, Wiener noise power spectrum, and detective quantum efficiency (DQE). The model was evaluated by comparing results with Monte Carlo calculations for x-ray converters based on amorphous selenium (a-Se) and lead (Pb), representing both low and high-Z materials. When electron transport considerations can be neglected, excellent agreement (within 3%) is obtained for each metric over the entire diagnostic energy range in both a-Se and Pb detectors up to 30 cycles/mm, the highest frequency tested. The cascaded model overstates the DQE when the electron range cannot be ignored. This occurs at approximately two cycles/mm in a-Se at an incident photon energy of 80 keV, whereas in Pb, excellent agreement is obtained for the DQE over the entire diagnostic energy range. However, within the context of mammography (20 keV) and micro-computed tomography (40 keV), the effects of electron transport on the DQE are negligible compared to fluorescence reabsorption, which can lead to decreases of up to 30% and 20% in a-Se and Pb, respectively, at 20 keV; and 10% and 5%, respectively, at 40 keV. It is shown that when Swank noise is identified in a Fourier model, the Swank factor must be frequency dependent. This factor decreases quickly with frequency, and in the case of a-Se and Pb, decreases by up to a factor of 3 at five cycles/mm immediately above the K edge. The frequency-dependent Swank factor is also equivalent to what we call the "photoelectric DQE," which describes signal and noise transfer through photoelectric interactions.
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Yuan J, Lin J, Xu A, Li H, Hu B, Chen J, Yao J, Dong H, Jiang M. Antepartum immunoprophylaxis of three doses of hepatitis B immunoglobulin is not effective: a single-centre randomized study. J Viral Hepat 2006; 13:597-604. [PMID: 16907846 DOI: 10.1111/j.1365-2893.2006.00738.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
To investigate the efficacy of antepartum administration of three doses of hepatitis B immunoglobulin (HBIg), currently being used in China, 250 pregnant women who were seropositive for hepatitis B e antigen (HBeAg) were randomly divided into study (117 cases) and control groups (133 cases). Subjects in the study group received HBIg 400 IU intramuscularly once a month at the third, second and first month before delivery; subjects in the control group received no antepartum treatment. All neonates received passive-active immunization after birth. The maternal hepatitis B virus (HBV) markers, hepatitis B surface antigen (HBsAg) titres and HBV deoxyribonucleic acid (DNA) levels were measured at week 28 of gestation (before the antepartum treatment) and at labour; the neonatal serum HBV markers were detected at birth and at 12 months after birth. No side-effects were found in any of the women or their neonates. No statistical differences were seen between the maternal HBsAg and HBV DNA levels of the study and control groups at labour nor the protective efficacy rates of postnatal immunoprophylaxis at 12 months after birth (P > 0.05, respectively). To conclude, antepartum administration of three doses of HBIg for the HBeAg-positive women is inefficacious.
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Yao J, Lawrance A. Performance Analysis and Optimization of Multi-User Differential Chaos-Shift Keying Communication Systems. ACTA ACUST UNITED AC 2006. [DOI: 10.1109/tcsi.2006.880343] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Yamauchi K, Takano Y, Kasai A, Hayakawa K, Hiramatsu N, Enomoto N, Yao J, Kitamura M. Screening and identification of substances that regulate nephrin gene expression using engineered reporter podocytes. Kidney Int 2006; 70:892-900. [PMID: 16820792 DOI: 10.1038/sj.ki.5001625] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Downregulation of nephrin in podocytes leads to development of proteinuria in human and experimental kidney diseases. However, little is understood about pathophysiologic substances that regulate nephrin expression. In this report, we established conditionally immortalized reporter podocytes REPON for sensitive, continuous monitoring of nephrin gene expression. A murine podocyte cell line harboring a temperature-sensitive simian virus 40 large T antigen was stably transfected with a gene encoding secreted alkaline phosphatase (SEAP) under the control of the 5.4 or 8.3 kb nephrin gene promoter. The established reporter cells REPON5.4 and REPON8.3 were exposed to various pathophysiologic substances, and culture media were subjected to SEAP assay to identify regulators of nephrin gene expression. Among the bioactive substances tested, three physiological ligands of nuclear receptors including all-trans-retinoic acid, 1,25-dihydroxyvitamin D3, and dexamethasone significantly activated the nephrin gene promoter in a dose-dependent manner. These effects were observed in both REPON5.4 and REPON8.3 and were associated with upregulation of nephrin mRNA. The effects of these substances were synergistic, and the maximum effect was observed by combination of three agents. In contrast, inflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha as well as phorbol ester significantly downregulated the activity of the nephrin promoter as well as nephrin gene expression. These results elucidated the bidirectional regulation of nephrin by distinct pathophysiologic substances and may provide molecular bases for explaining how proteinuria is induced under pathologic situations and why some ligands for nuclear receptors have the anti-proteinuric potential.
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Hwang JM, Rao A, Shieh E, Yao J, Tome M. Treatment of HIV positive anal cancer patients with chemoradiation. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.4154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
4154 Background: Tolerance and outcomes of HIV+ anal cancer patients are questioned, especially since the emergence of High Active Anti-Retroviral Therapy (HAART) in the mid-1990s. Our experience in treating these patients before and during the HAART era is reported. Methods: From 1987–2003, 19 HIV+ invasive anal cancer patients were treated with: 30–60 Gy pelvic RT (2 Gy/d) + Mitomycin C (10 mg/m2 bolus on d1) + 5-FU (1000 mg/m2/d, continuous infusion d1–4 and 28–31). Results: Mean CD-4 count at cancer diagnosis was 311, with 9 on HAART. Mean CD-4 count for HAART was 383 and 247 for non-HAART. Stage distribution: 1 T1, 9 T2, 9 T3, 18 N0, 1 N3. Mean f/u was 40 months. 79% had complete response after chemoRT. 4 had locally persistent disease. There was 1 loco-regional recurrence and 2 distant metastases. 79% of the cohort is colostomy-free. Median OS has not been reached. OS at 2 and 3 years were: 88%and 79%, with 10 Alive and NED, 1 Alive with disease, 3 Dead of disease, 5 Dead from intercurrent disease (all secondary to AIDS). 1.5 year DFS was 74%. Break and CD-4 count < 200 had a statistically significant negative impact on DFS, but not OS. HAART did not affect either factor. 11 had RT break for median of 17 days. There was no Grade 4 skin toxicity. All completed the 2nd 5-FU cycle: 7 had delay (median 7 days) and 3 had dose decrease. There were 6 hospitalizations: 5 neutropenic fevers and 1 perineal abscess rupture. WBC Toxicity: 6-Grade 3 and 2-Grade 4. Platelet Toxicity: 2-Grade 3. Heme toxicity was not affected by HAART or CD4 count < 200. There were no treatment related deaths. Conclusion: HIV+ anal cancer patients have reasonable tolerance and outcomes with chemoRT. CD-4 count < 200 and break were negative prognostic factors for DFS. Our 79% colostomy free survival is similar to RTOG 9208, where suboptimal control was attributed to mandatory RT break. Factors influencing break include heme and skin toxicity. To improve the therapeutic ratio, substitution of Mitomycin-C with Cisplatin, IMRT, and Ethyol are being explored. No significant financial relationships to disclose.
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Braiteh FS, Yao J, Camacho LH, Ng C, Hong DS, Harris P, Dhillon N, Kurzrock R. Phase I study of the safety and efficacy of atiprimod, a novel azaspirine, for patients with advanced cancer. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.13050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
13050 Background: Atiprimod (N-N-diethl-8,8-dipropyl-2-azaspiro [4.5] decane-2-propanamine) is an oral cationic azaspirane that suppresses angiogenesis by inhibiting both bFGF and VEGF induced proliferation and migration. Atiprimod has been shown to down-regulate multiple growth factors involved in tumor progressions and metastases, including IL-6, TNF-α, and VEGF. Methods: This is an ongoing, single-center, open-label, ascending dose (modified Fibonacci) Phase I trial of oral atiprimod in patients with advanced cancers (3+3 design). Atiprimod was given orally for 14 days every 28-day cycle. The primary objectives are to identify the MTD and to evaluate the safety of atiprimod; the secondary objectives include measuring PK and describing efficacy. Data from these patients enrolled are presented here. Results: Fourteen patients have been treated to date with 60 mg tablets (N = 3), 60 mg capsules (N = 3), 90 mg capsules (N = 3) and 120 mg capsules (N = 5). The most common side effects, which occurred in over half the patients, were related to the gastrointestinal system, and include nausea (11), diarrhea (7), vomiting (4) abdominal pain (2) and dyspepsia (2). These events were generally low-grade, occurred primarily during days of active drug administration and tended to resolve during off-drug days. Less common adverse events were sinus headaches, and elevated serum transaminases, alkaline phosphatase and creatinine. One patient who received prolonged therapy (7 months) developed fever and multi-organ failure of unclear etiology. One patient with uterine leiomyosarcoma experienced a DLT (syncope and hypotension) at 120 mg/day, and that dose level is therefore being expanded up to 6 patients. One patient with midgut carcinoid tumor and liver metastasis achieved a partial remission lasting 2+ months (50% decrease in maximum diameter by RECIST). Three patients (carcinoid = 2 and thymoma = 1) had stable disease for four, four and six months, respectively. Conclusions: Preliminary data indicate that atiprimod was reasonably tolerated, with predominantly gastrointestinal side effects. There is early evidence of anti-tumor activity in carcinoid tumors. Dose escalation continues. [Table: see text]
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Hoff PM, Hoff AO, Phan AT, Sherman SI, Yao J, White N, Phan L, Abbruzzese JL, Gagel RF. Phase I/II trial of capecitabine (C), dacarbazine (D) and imatinib (I) (CDI) for patients (pts) metastatic medullary thyroid carcinomas (MTC). J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.13048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
13048 Background: MTC is a rare tumor that responds poorly to conventional chemotherapy. 5-FU and D are frequently used, with an expected response rate of around 15%. MTC is often associated with multiple endocrine neoplasia type 2, an autosomal dominant syndrome caused by a mutation in the RET proto-oncogene which encodes RET, a tyrosine kinase receptor. I is a tyrosine kinase inhibitor with activity against c-Kit, PDGF and possibly RET, and we postulated that its addition to chemotherapy would increase its efficacy against this disease. Methods: We designed a phase I/II trial combining escalating doses of oral C, IV D and oral I. Pts with any advanced solid tumors were eligible for the phase I part of the trial. Results: 13 pts were entered and 12 were eligible (7 MTC, 2 adrenocortical, 1 islet-cell, 1 insular thyroid and 1 small cell). 4 pts did not complete one cycle (1 pt withdrew after 5 days and 2 pts progressed in less than 10 days and were replaced for toxicity analysis, 1 had a DLT and is included). 3 patients were entered in dose level 1, without DLT. 2 out of 6 pts developed DLT at the second dose level (1 G 3 fatigue and 1 G3 hypokalemia). Three additional pts are being entered on dose level 1. The first one had PD after 7 days and is being replaced. For the 11 pts who were evaluable, best response was 3 SD (range 3 to 9 + months) and 8 PD. Conclusions: The combination of CDI is feasible but has resulted in an unexpected pattern of toxicity in this patient population, with fatigue and hypokalemia as the DLT. No significant diarrhea or hand-foot syndrome was seen. Only G1 and 2 fluid retention and neutropenia have been encountered. Only minor reduction in tumor size has been seen among these heavily pretreated pts. Once the phase I is complete, the trial will continue in a phase II setting for untreated MTC pts. [Table: see text] [Table: see text]
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