Repurposing AZD5438 and Dabrafenib for Cisplatin-Induced AKI

SIGNIFICANCE STATEMENT

To combat both untoward effects of nephrotoxicity and ototoxicity in cisplatin-treated patients, two potential therapeutic oral anticancer drugs AZD5438 and dabrafenib, a phase-2 clinical trial protein kinase CDK2 inhibitor and an US Food and Drug Administration-approved drug BRAF inhibitor, respectively, were tested in an established mouse AKI model. Both drugs have previously been shown to protect significantly against cisplatin-induced hearing loss in mice. Each drug ameliorated cisplatin-induced increases in the serum biomarkers BUN, creatinine, and neutrophil gelatinase-associated lipocalin. Drugs also improved renal histopathology and inflammation, mitigated cell death by pyroptosis and necroptosis, and significantly enhanced overall survival of cisplatin-treated mice.

BACKGROUND

Cisplatin is an effective chemotherapy agent for a wide variety of solid tumors, but its use is dose-limited by serious side effects, including AKI and hearing loss. There are no US Food and Drug Administration-approved drugs to treat both side effects. Recently, two anticancer oral drugs, AZD5438 and dabrafenib, were identified as protective against cisplatin-induced hearing loss in mice. We hypothesize that similar cell stress and death pathways are activated in kidney and inner ear cells when exposed to cisplatin and tested whether these drugs alleviate cisplatin-induced AKI.

METHODS

The HK-2 cell line and adult FVB mice were used to measure the protection from cisplatin-induced cell death and AKI by these drugs. Serum markers of kidney injury, BUN, creatinine, and neutrophil gelatinase-associated lipocalin as well as histology of kidneys were analyzed. The levels of markers of kidney cell death, including necroptosis and pyroptosis, pERK, and proliferating cell nuclear antigen, were also examined by Western blotting and immunofluorescence. In addition, CDK2 knockout (KO) mice were used to confirm AZD5438 protective effect is through CDK2 inhibition.

RESULTS

The drugs reduced cisplatin-induced cell death in the HK-2 cell line and attenuated cisplatin-induced AKI in mice. The drugs reduced serum kidney injury markers, inhibited cell death, and reduced the levels of pERK and proliferating cell nuclear antigen, all of which correlated with prolonged animal survival. CDK2 KO mice were resistant to cisplatin-induced AKI, and AZD5438 conferred no additional protection in the KO mice.

CONCLUSIONS

Cisplatin-induced damage to the inner ear and kidneys shares similar cellular beneficial responses to AZD5438 and dabrafenib, highlighting the potential therapeutic use of these agents to treat both cisplatin-mediated kidney damage and hearing loss.

Dabrafenib protects from cisplatin-induced hearing loss in a clinically relevant mouse model

The widely used chemotherapy cisplatin causes permanent hearing loss in 40%-60% of patients with cancer. One drug, sodium thiosulfate, is approved by the FDA for use in pediatric patients with localized solid tumors for preventing cisplatin-induced hearing loss, but more drugs are desperately needed. Here, we tested dabrafenib, an FDA-approved BRAF kinase inhibitor and anticancer drug, in a clinically relevant multidose cisplatin mouse model. The protective effects of dabrafenib, given orally twice daily with cisplatin, were determined by functional hearing tests and cochlear outer hair cell counts. Toxicity of the drug cotreatment was evaluated, and levels of phosphorylated ERK were measured. A dabrafenib dose of 3 mg/kg BW, twice daily, in mice, was determined to be the minimum effective dose, and it is equivalent to one-tenth of the daily FDA-approved dose for human cancer treatment. The levels of hearing protection acquired, 20-25 dB at the 3 frequencies tested, in both female and male mice, persisted for 4 months after completion of treatments. Moreover, dabrafenib exhibited a good in vivo therapeutic index (> 25), protected hearing in 2 mouse strains, and diminished cisplatin-induced weight loss. This study demonstrates that dabrafenib is a promising candidate drug for protection from cisplatin-induced hearing loss.

In Vivo Study of Expanded Polytetrafluoroethylene Vascular Suture

Routine use of high-quality suture material has often been described as a factor in preventing complications such as false aneurysms, infection, and me chanical failure of implanted gafts. Optimal characteristics for a vascular su ture are to maintain its strength without causing an important "foreign body" reaction. Polypropylene monofilament has both characteristics and successfully replaced braided sutures for many years. A new monofilament suture material, which is made of expanded polytetrafluoroethylene (EPTFE), has recently been introduced. The purpose of the present study was to evaluate this new vascular suture and compare it with the widely and successfully used polypropylene su ture. The authors implanted a total of 20 infrarenal aortic reconstructions in dogs using both sutures to perform each anastomosis. Two dogs were sacrificed after 3, 7, 10, 14, 21, 30, 60, 120, 285, and 360 days.

Light and scanning electron microscopy of the anastomotic site was routinely performed in order to compare the two suture materials. Thickness of inflam matory reaction around the sutures was measured at three different sites of each suture and statistically compared. Inflammatory reaction was minimal for both sutures and no significant difference was noticed by use of the Student's T- test (p=NS). No ingrowth was shown in either suture. EPTFE, in contrast to polypropylene, at scan electron microscopy, showed a nice layer of fibrin sur rounding the suture and a tendency to adapt to mechanical stress by being oval, elliptical, or circular. In the authors' opinion, EPTFE suture is, therefore, a valuable alternative for use in cardiovascular surgery.

Interstate Differences in Individual Income Taxes

Income taxes vary significantly across states. Typical measures of these varia-tions utilize aggregate measures, such as per capita taxes or taxes per thousand dollars of income. In this article the income tax systems, as opposed to the taxes paid, are described and compared for the various states. It is demonstrated that the diversity in the treatment of individuals for income tax purposes is vast. We propose that analysis of state taxation and its effect on individuals and businesses be conducted on a disaggregated basis.

In Vivo Study of Collagen-Impregnated Double Velour Prosthesis

Cross-linked bovine collagen treatment of double velour prosthesis has re cently been introduced to help the graft ingrowth and neointima development in high-porosity graft without any need of preclotting. The authors have im planted (end-to-end) a total of 18 double velour 6-mm grafts (length 6 cm) in the infrarenal aorta of 18 dogs (15-25 kg). Nine prostheses were treated with colla gen (DVC) and 9 were untreated (DV). Animals with both kinds of prosthesis were sacrificed 3, 7, 10, 14, 21, 30, 60, 120, and 360 days after the implant. Preclotting was required only in DV grafts even though both grafts had some porosity (1,900 cc/min/cm2). Organization of the neointima of both grafts was studied and compared by light and scanning electron microscopy. DVC grafts showed an earlier (3-10 days) deposition of neoendothelial cells and a signifi cantly thicker neointima development within the first week from graft implant (p < 0.02).

No statistical differences were noted in later neoendothelialization. Both grafts had a multifocal neoendothelial surface development around the neovasa vasorum in longer survival (days 21-360) whereas the ingrowth started from anastomoses in the early survival (days 3-14).

In conclusion, DVC grafts, owing to the collagen treatment, do not require any preclotting despite their high porosity (equal to DV) and successfully accel erate short-term neointima development (> DV).

Cutaneous expression of TREM, vitamin D receptor and HMGB1 in vitamin D deficiency

Signaling pathways of the vitamin D receptor (VDR) and the triggering receptor expressed on myeloid cells (TREM) have been independently implicated in the biology of numerous of cutaneous pathologies. There is substantial evidence for possible crosstalk between these pathways, though the relationship between VDR and TREMs remains unclear. In this study, we characterize the effects of vitamin D-deficiency and sufficiency on the cutaneous expression of TREM-1, TREM-2, VDR, HMGB1, and RAGE. Cutaneous tissue isolated from Yucatan microswine were immunohistochemically evaluated for epidermal expression of TREM-1, TREM-2, VDR, HMGB1, and RAGE. The swine were fed a vitamin D-deficient or vitamin D-sufficient diet to examine the role of vitamin D state on levels of these markers. In vitamin D-sufficient animals, keratinocytes exhibited elevated levels of TREM-1, TREM-2. Additionally, TREM-1 expression predominated in basal cells, whereas TREM-2 levels were higher in keratinocytes, regardless of vitamin D state. Levels of HMGB1 and RAGE did not differ by vitamin D state. VDR expression was consistently higher in the cytoplasm and nuclei of basal cells, when compared to keratinocytes. Our findings suggest a role of vitamin D in signaling of TREM pathways. Additionally, the TREM ratio may play a role in keratinocyte differentiation and should be explored further. Possible signaling crosstalk between these pathways has a potential role in progression of cutaneous malignancies and other inflammatory pathologies.

Vitamin D Supplementation Reduces Intimal Hyperplasia and Restenosis following Coronary Intervention in Atherosclerotic Swine

Vitamin D is a fat-soluble steroid hormone that activates vitamin D receptor to regulate multiple downstream signaling pathways and transcription of various target genes. There is an association between vitamin D deficiency and increased risk for cardiovascular disease. However, most of the studies are observational and associative in nature with limited data on clinical application. Thus, there is a need for more prospective randomized controlled studies to determine whether or not vitamin D supplementation provides cardiovascular protection. In this study, we examined the effects of the deficiency and supplementation of vitamin D on coronary restenosis following coronary intervention in atherosclerotic Yucatan microswine. Twelve Yucatan microswine were fed vitamin D-deficient (n = 4) or -sufficient (n = 8) high cholesterol diet for 6-months followed by coronary intervention. Post-intervention, swine in the vitamin D-sufficient high cholesterol diet group received daily oral supplementation of either 1,000 IU (n = 4) or 3,000 IU (n = 4) vitamin D3. Six months later, optical coherence tomography (OCT) was performed to monitor the development of intimal hyperplasia and restenosis. Animals were euthanized to isolate arteries for histomorphometric and immunohistochemical studies. Animals had graded levels of serum 25(OH)D; vitamin D-deficient (15.33 ± 1.45 ng/ml), vitamin D-sufficient + 1,000 IU oral vitamin D post-intervention (32.27 ± 1.20 ng/ml), and vitamin D-sufficient + 3,000 IU oral vitamin D post-intervention (51.00 ± 3.47 ng/ml). Findings from the OCT and histomorphometric studies showed a decrease in intimal hyperplasia and restenosis in vitamin D-supplemented compared to vitamin D-deficient swine. Vitamin D supplementation significantly decreased serum levels of TNF-α and IFN-γ, upregulated serum levels of IL-10, and had no effect on serum IL-6 levels. These findings suggest that vitamin D supplementation limits neointimal formation following coronary intervention in atherosclerotic swine and provide the support for vitamin D supplementation to protect against the development of coronary restenosis.

Progress toward clonable inorganic nanoparticles

Pseudomonas moraviensis stanleyae was recently isolated from the roots of the selenium (Se) hyperaccumulator plant Stanleya pinnata. This bacterium tolerates normally lethal concentrations of SeO3(2-) in liquid culture, where it also produces Se nanoparticles. Structure and cellular ultrastructure of the Se nanoparticles as determined by cellular electron tomography shows the nanoparticles as intracellular, of narrow dispersity, symmetrically irregular and without any observable membrane or structured protein shell. Protein mass spectrometry of a fractionated soluble cytosolic material with selenite reducing capability identified nitrite reductase and glutathione reductase homologues as NADPH dependent candidate enzymes for the reduction of selenite to zerovalent Se nanoparticles. In vitro experiments with commercially sourced glutathione reductase revealed that the enzyme can reduce SeO3(2-) (selenite) to Se nanoparticles in an NADPH-dependent process. The disappearance of the enzyme as determined by protein assay during nanoparticle formation suggests that glutathione reductase is associated with or possibly entombed in the nanoparticles whose formation it catalyzes. Chemically dissolving the nanoparticles releases the enzyme. The size of the nanoparticles varies with SeO3(2-) concentration, varying in size form 5 nm diameter when formed at 1.0 μM [SeO3(2-)] to 50 nm maximum diameter when formed at 100 μM [SeO3(2-)]. In aggregate, we suggest that glutathione reductase possesses the key attributes of a clonable nanoparticle system: ion reduction, nanoparticle retention and size control of the nanoparticle at the enzyme site.

The role of high cholesterol-high fructose diet on coronary arteriosclerosis

The effect of fructose in conjunction with high cholesterol diet in the development of atherosclerotic lesions in coronary arteries is not well established. Microswine were fed high cholesterol (HC) or a high cholesterol-high fructose (HCHF) diet containing 18-20% calories from fructose. All swine had high levels of serum cholesterol and non-HDL, thickened intima and accumulation of collagen in the coronaries. Swine fed with HC diet had less stenosis in coronary arteries, lower serum levels of non-HDL, triglycerides, cholesterol, and blood glucose than HCHF group. Coronary lesions in the HC swine were not as progressed as in HCHF and showed low LDL-expressed lipid-laden foam cells. The M1/M2 macrophage phenotype in the HCHF swine differed with the progression of atherosclerosis, with higher density of M1-phenotype in HCHF swine. There was high expression of CCR7 (M1-phenotype) in more advanced lesions in the fibrous cap-like areas, whereas M2-macrophages were abundant in the foam-cell cores. These findings suggest that the addition of a fructose to high cholesterol diet accelerates atherosclerotic lesions in coronary arteries with an increase in M1-macrophages and the propensity to develop features of metabolic syndrome.

Triggering Receptor Expressed on Myeloid Cells in Cutaneous Melanoma

The tumor microenvironment plays an important role in the progression of melanoma, the prototypical immunologic cutaneous malignancy. The triggering receptor expressed on myeloid cells (TREM) family of innate immune receptors modulates inflammatory and innate immune signaling. It has been investigated in various neoplastic diseases, but not in melanoma. This study examines the expression of TREM-1 (a proinflammatory amplifier) and TREM-2 (an anti-inflammatory modulator and phagocytic promoter) in human cutaneous melanoma and surrounding tissue. Indirect immunofluorescence staining was performed on skin biopsies from 10 melanoma patients and staining intensity was semiquantitatively scored. Expression of TREM-1 and TREM-2 was higher in keratinocytes than melanoma tissue (TREM-1: p < 0.01; TREM-2: p < 0.01). Whereas TREM-2 was the dominant isoform expressed in normal keratinocytes, TREM-1 expression predominated in melanoma tissue (TREM-1 to TREM-2 ratio: keratinocytes = 0.78; melanoma = 2.08; p < 0.01). The increased TREM ratio in melanoma tissue could give rise to a proinflammatory and protumor state of the microenvironment. This evidence may be suggestive of a TREM-1/TREM-2 paradigm in which relative levels dictate inflammatory and immune states, rather than absolute expression of one or the other. Further investigation regarding this paradigm is warranted and could carry prognostic or therapeutic value in treatment for melanoma.

Pre-treatment step with Leuconostoc mesenteroides or L. pseudomesenteroides strains removes furfural from Zymomonas mobilis ethanolic fermentation broth

Furfural is an inhibitor of growth and ethanol production by Zymomonas mobilis. This study used a naturally occurring (not GMO) biological pre-treatment to reduce that amount of furfural in a model fermentation broth. Pre-treatment involved inoculating and incubating the fermentation broth with strains of Leuconostoc mesenteroides or Leuconostoc pseudomesenteroides. The Leuconostoc strains converted furfural to furfuryl alcohol without consuming large amounts of dextrose in the process. Coupling this pre-treatment to ethanolic fermentation reduced furfural in the broth and improved growth, dextrose uptake and ethanol formation. Pre-treatment permitted ethanol formation in the presence of 5.2 g L(-1) furfural, which was otherwise inhibitive. The pre-treatment and presence of the Leuconostoc strains in the fermentation broth did not interfere with Z. mobilis ethanolic fermentation or the amounts of ethanol produced. The method suggests a possible technique for reducing the effect that furfural has on the production of ethanol for use as a biofuel.

Neoadjuvant treatment of Dermatofibrosarcoma Protuberans of pancreas with Imatinib: case report and systematic review of literature

Dermatofibrosarcoma Protuberans (DFSP) is a rare skin tumor, characterized by frequent local recurrence but is seldom metastatic. It is histologically characterized by storiform arrangement of spindle cells. Cytogenetically, most tumors are characterized by translocation 17:22 leading to overexpression of tyrosine kinase PDGFB which can be targeted with tyrosine kinase inhibitor, Imatinib. We describe the first case of unresectable pancreatic metastases from DFSP treated with neoadjuvant Imatinib and subsequently R0 metastectomy. Additionally, a comprehensive systematic review of DFSP pancreatic metastases and the current published data on the use of Imatinib in DFSP is summarized.

Immunological and molecular basis of nonalcoholic steatohepatitis and nonalcoholic fatty liver disease

The prevalence of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) is rising worldwide with the increasing incidence of obesity, Type 2 diabetes mellitus and metabolic syndrome. NASH is currently one of the most common indications of liver transplantation in the United States. The immune system plays a major role in the pathogenesis of NAFLD/NASH. The metabolic changes, associated with obesity and metabolic syndrome, induce immunological responses resulting in NAFLD and further aggravation of the metabolic derangement in a feed-forward loop. Genetic and endocrine factors modulate the immunological and metabolic responses and determine the pathophysiological features of NAFLD. Histologically, NAFLD is a spectrum that ranges from simple hepatic steatosis to severe steatohepatitis, liver cirrhosis and/or hepatocellular carcinoma. Liver cirrhosis and hepatocellular carcinoma are responsible for the morbidity and mortality of the disease. This article is a critical evaluation of our current knowledge of the immunological and molecular basis of the disease.

Vitamin D receptor and CD86 expression in the skin of vitamin D-deficient swine

The immunomodulatory role of vitamin D in many diseases is well established. However, the relationship between vitamin D status and skin cancers is unclear. In this study, we examined the effect of vitamin D deficiency and sufficiency on VDR, NF-κB, and CD86 in the epidermis of Yucatan microswine tragi. All of these proteins have known roles in the pathogenesis of cutaneous malignancies such as melanoma and non-melanoma skin cancer. There was weaker and less discrete nuclear staining for VDR and weaker CD86 immunoreactivity with patchy membranous expression in the epidermis of vitamin D-deficient compared to vitamin D-sufficient swine. There was no difference in the immunostaining for NF-κB. Since VDR and CD86 expression are decreased in the setting of melanoma and non-melanoma skin cancers, our findings suggest a potential role of vitamin D-deficiency in the progression of skin malignancies.

A Rhizobium selenitireducens protein showing selenite reductase activity

Biobarriers remove, via precipitation, the metalloid selenite (SeO₃⁻²) from groundwater; a process that involves the biological reduction of soluble SeO₃⁻² to insoluble elemental red selenium (Se⁰). The enzymes associated with this reduction process are poorly understood. In Rhizobium selenitireducens at least two enzymes are potentially involved; one, a nitrite reductase reduces SeO₃⁻² to Se⁰ but another protein may also be involved which is investigated in this study. Proteins from R. selenitireducens cells were precipitated with ammonium sulfate and run on native electrophoresis gels. When these gels were incubated with NADH and SeO₃⁻² a band of precipitated Se⁰ developed signifying the presence of a SeO₃⁻² reducing protein. Bands were cut from the gel and analyzed for peptides via LCMSMS. The amino acid sequences associated with the bands indicated the presence of an NADH:flavin oxidoreductase that resembles YP_001326930 from Sinorhizobium medicae. The protein is part of a protein family termed old-yellow-enzymes (OYE) that contain a flavin binding domain. OYE enzymes are often involved in protecting cells from oxidative stress and, due in part to an active site that has a highly accessible binding pocket, are generally active on a wide range of substrates. This report is the first of an OYE enzyme being involved in SeO₃⁻² reduction.

Abstract 272: Epidermal Growth Factor Dependent Collagen Loss in Human Carotid Plaques is Mediated by Matrix Metalloproteinase-9

Aims

Atherogenesis is a chronic progressive process that develops over several decades. Changes in the structure and composition of extracellular matrix (ECM) play an important role in the process of atherosclerosis. Matrix metalloproteinases (MMPs) and growth factors present in atherosclerotic human plaques could be related to plaque remodeling and increased risk for plaque destabilization and rupture.

Hypothesis

Selective inhibition of elevated MMP-9 and epidermal growth factor receptor (EGFR) increases fibrillar collagens (Type I and III) in vascular smooth muscle cells (VSMCs) from symptomatic (S) and asymptomatic (AS) patients with carotid stenosis.

Methods and results

Cultured human VSMCs from both AS and S patients were treated with or without epidermal growth factor (EGF). The proteolytic activity of MMP-9 and MMP-2 was quantified by gelatin zymography. The mRNA transcripts of MMP-9, MMP-1, EGFR and collagen types I (COL1A1 and COL1A2) and III (COL3A1) were analyzed by qPCR. EGF treatment significantly increased MMP-9 activity and mRNA transcripts for MMP-9, MMP-1and EGFR, while mRNA transcripts for collagen types I and III were decreased in both AS and S groups. Collagen type I and type III mRNA transcripts were significantly decreased in symptomatic VSMCs compared to cells from AS. Inhibition of EGFR with AG1478 and MMP-9 using small molecule inhibitor and transfection with MMP-9 siRNA decreased the activity and mRNA expression of MMP-9 and increased mRNA transcripts of collagen I and III in EGF treated VSMCs.

Conclusion

These results reveal a novel mechanism by which MMP-9 induced by EGFR activation could be a leading cause of plaque instability in patients with carotid stenosis; and the selective blockade of EGFR and MMP-9 may be a novel strategy and a promising target for treating human unstable and vulnerable plaques.

Isolation and characterization of lignin-degrading bacteria from rainforest soils

The deconstruction of lignin to enhance the release of fermentable sugars from plant cell walls presents a challenge for biofuels production from lignocellulosic biomass. The discovery of novel lignin-degrading enzymes from bacteria could provide advantages over fungal enzymes in terms of their production and relative ease of protein engineering. In this study, 140 bacterial strains isolated from soils of a biodiversity-rich rainforest in Peru were screened based on their oxidative activity on ABTS, a laccase substrate. Strain C6 (Bacillus pumilus) and strain B7 (Bacillus atrophaeus) were selected for their high laccase activity and identified by 16S rDNA analysis. Strains B7 and C6 degraded fragments of Kraft lignin and the lignin model dimer guaiacylglycerol-β-guaiacyl ether, the most abundant linkage in lignin. Finally, LC-MS analysis of incubations of strains B7 and C6 with poplar biomass in rich and minimal media revealed that a higher number of compounds were released in the minimal medium than in the rich one. These findings provide important evidence that bacterial enzymes can degrade and/or modify lignin and contribute to the release of fermentable sugars from lignocellulose.

Decreased expression of vitamin D receptors in neointimal lesions following coronary artery angioplasty in atherosclerotic swine

Background

Inflammatory cytokines, such as TNF-α, play a key role in the pathogenesis of occlusive vascular diseases. Activation of vitamin D receptors (VDR) elicits both growth-inhibitory and anti-inflammatory effects. Here, we investigated the expression of TNF-α and VDR in post-angioplasty coronary artery neointimal lesions of hypercholesterolemic swine and examined the effect of vitamin D deficiency on the development of coronary restenosis. We also examined the effect of calcitriol on cell proliferation and effect of TNF-α on VDR activity and expression in porcine coronary artery smooth muscle cells (PCASMCs) in-vitro.

Methodology/Principal Findings

Expression of VDR and TNF-α and the effect of vitamin D deficiency in post-angioplasty coronary arteries were analyzed by immunohistochemistry and histomorphometry. Cell proliferation was examined by thymidine and BrdU incorporation assays in cultured PCASMCs. Effect of TNF-α-stimulation on the activity and expression of VDR was analyzed by luciferase assay, immunoblotting and immunocytochemistry. In-vivo, morphometric analysis of the tissues revealed typical lesions with significant neointimal proliferation. Histological evaluation showed expression of smooth muscle α-actin and significantly increased expression of TNF-α in neointimal lesions. Interestingly, there was significantly decreased expression of VDR in PCASMCs of neointimal region compared to normal media. Indeed, post-balloon angioplasty restenosis was significantly higher in vitamin D-deficient hypercholesterolemic swine compared to vitamin D-sufficient group. In-vitro, calcitriol inhibited both serum- and PDGF-BB-induced proliferation in PCASMCs and TNF-α-stimulation significantly decreased the expression and activity of VDR in PCASMCs.

Conclusions/Significance

These data suggest that significant downregulation of VDR in proliferating smooth muscle cells in neointimal lesions could be due to atherogenic cytokines, including TNF-α. Vitamin D deficiency potentiates the development of coronary restenosis. Calcitriol has anti-proliferative properties in PCASMCs and these actions are mediated through VDR. This could be a potential mechanism for uncontrolled growth of neointimal cells in injured arteries leading to restenosis.

Vitamin D receptor expression in the mucosal tissue at the gastroesophageal junction

Barrett's esophagus is considered to be a precursor to adenocarcinoma and the information on VDR expression in normal and Barrett's esophagus is significantly lacking. In this study, we examined the expression of VDR in the lower esophagus and gastric cardia of normal and Barrett's esophagus by immunofluorescence. Columnar mucosa but not squamous mucosa at the gastroesophageal junction showed positive immunofluorescence to VDR. Submucosal glands and ducts deep to the normal squamous mucosa stained positive for VDR and localized in the cytoplasm and perinuclear regions with no nuclear staining. Interestingly, Barrett's mucosa stained strongly positive for VDR. Glandular structures in the mucosal layer were far less abundant in the Barrett's mucosa than in the normal gastric mucosa. As a result, fewer structures deep to the Barrett's epithelial layer stained positive for VDR when compared to normal gastric mucosa. These findings suggest that in normal esophagus VDR expression is restricted to columnar epithelium and glandular structures. Furthermore, strong VDR expression in Barrett's mucosa may indicate an increased sensitivity of this tissue to endogenous or therapeutic effects of Vitamin D.

Abstract 469: Vitamin D Deficiency Potentiates Restenosis Following Coronary Angioplasty in Hypercholesterolemic Swine

Introduction: Vitamin D is a sectosteroid that functions through vitamin D receptor (VDR), a transcription factor, which regulates various downstream signaling pathways and controls the transcription of many targets genes. Vitamin D deficiency is associated increased risk of incident congestive heart failure, myocardial infarction, and cardiovascular disease mortality. However, most of the studies which identified an association between lower vitamin D intake or lower 25-hydroxyvitamin D and increased risk of cardiovascular disease are observational or cross-sectional studies. There has been no careful study evaluating the effect of vitamin D supplementation on coronary artery disease outcome following coronary intervention.

Objective: The purpose of this study was to examine the effect of vitamin D deficiency and vitamin D supplementation on coronary artery restenosis following balloon angioplasty in hypercholesterolemic Yucatan microswine.

Methods: Twelve female microswine were fed vitamin D-deficient or vitamin D-sufficient high cholesterol diet. At six months, animals underwent coronary angioplasty. Following coronary intervention swine in the vitamin D-sufficient high cholesterol diet group received supplementation of 1,000 IU or 3,000 IU of vitamin D3. Six months later, angiogram was performed followed by optical coherence tomography to monitor the development of intimal hyperplasia and restenosis. At the end of 12 months animals were euthanized, coronary arteries were harvested and morphological and histological studies were performed.

Results: Findings from the optical coherence tomography and histomorphometric studies showed a significant decrease in neointimal hyperplasia, increase in in-segment lumen diameter, and decrease in the intima-media ratio in coronary arteries following balloon angioplasty in swine with vitamin D supplementation compared to the animals with vitamin D-deficient status. In the in-vitro studies, calcitriol inhibited proliferation of coronary artery smooth muscle cells.

Conclusion: These data suggest that vitamin D deficiency increases intimal hyperplasia and restenosis following coronary balloon angioplasty in hypercholesterolemic swine. Since vitamin D inhibits smooth muscle cell proliferation, supplementation of non-secosteroidal VDR ligands prior to coronary intervention could help in preventing the neointimal formation and restenosis.

The influence of nitrate on selenium in irrigated agricultural groundwater systems

Selenium (Se) contamination of groundwater is an environmental concern especially in areas where aquifer systems are underlain by Se-bearing geologic formations such as marine shale. This study examined the influence of nitrate (NO₃) on Se species in irrigated soil and groundwater systems and presents results from field and laboratory studies that further clarify this influence. Inhibition of selenate (SeO₄) reduction in the presence of NO₃ and the oxidation of reduced Se from shale by autotrophic denitrification were investigated. Groundwater sampling from piezometers near an alluvium-shale interface suggests that SeO₄ present in the groundwater was due in part to autotrophic denitrification. Laboratory shale oxidation batch studies indicate that autotrophic denitrification is a major driver in the release of SeO₄ and sulfate. Similar findings occurred for a shale oxidation flow-through column study, with 70 and 31% more reduced Se and S mass, respectively, removed from the shale material in the presence of NO₃ than in its absence. A final laboratory flow-through column test was performed with shallow soil samples to assess the inhibition of SeO₄ reduction in the presence of NO₃, with results suggesting that a concentration of NO₃ of approximately 5 mg L or greater will diminish the reduction of SeO₄. The inclusion of the fate and transport of NO₃ and dissolved oxygen is imperative when studying or simulating the fate and transport of Se species in soil and groundwater systems.

Vitamin D receptor expression and neoadjuvant therapy in esophageal adenocarcinoma

Esophageal adenocarcinoma carries a poor prognosis. Tumor response to neoadjuvant therapy is a key prognostic factor in patients with adenocarcinoma of the esophagus, but is inconsistent. Identifying tumor characteristics that portend a favorable response to neoadjuvant therapy would be a valuable clinical tool. The anticancer actions of vitamin D and its receptor may have implications. In this study, 15 biopsy specimens were procured retrospectively from patients being treated for adenocarcinoma of the esophagus. The tissue was immunostained for the vitamin D receptor and compared on the basis of response to neoadjuvant therapy. Tumors that did not respond to neoadjuvant therapy had greater expression of VDR than tumors that responded completely. Expression of VDR declined with tumor de-differentiation. The data suggest that a relationship between vitamin D receptor expression and response to neoadjuvant therapy is plausible.

Enterobacter soli sp. nov.: a lignin-degrading γ-proteobacteria isolated from soil

A Gram-negative bacterium that formed cream-colored colonies designated strain LF7 was isolated from soil collected in the Tambopata National Reserve in Madre de Dios, Peru. 16S rRNA sequence comparisons indicate that LF7 is a novel Enterobacter sp. closely related to E. asburiae JCM 6051(T) [AB004744] and E. aerogenes JCM 1235(T) [AB004750] based on their sequence homologies (p-distance: 1.06 and 1.19%, respectively). DNA G + C content was 52.8 mol% which is within the range reported for E. asburiae (55-57 mol%). The major cellular fatty acids present in the LF7 strain were C(16:0) (27.3%), C(16:1) ω7c and/or C(16:1) ω6c (16.3%), C(18:1) ω7c (16.1%), C(17:0) cyclo (12.4%), C(14:0) 3-OH and/or C(16:1) iso-I (8.9%), C(14:0) (7.6%), C(12:0) (3.9%), C(17:0) (2.4%), C(13:0) 3-OH and/or C(15:1) iso-H (1.7%), C(13:0) (1.1%), and C(18:2) ω6,9c and/or C(18:0) ante (0.5%). The cellular fatty acid profile, G + C content, phenotypic and biochemical characteristics were consistent with its placement in the genus Enterobacter. The name Enterobacter soli is proposed for this bacterium.

Increased electrical output when a bacterial ABTS oxidizer is used in a microbial fuel cell

Microbial fuel cells (MFCs) are a technology that provides electrical energy from the microbial oxidation of organic compounds. Most MFCs use oxygen as the oxidant in the cathode chamber. This study examined the formation in culture of an unidentified bacterial oxidant and investigated the performance of this oxidant in a two-chambered MFC with a proton exchange membrane and an uncoated carbon cathode. DNA, FAME profile and characterization studies identified the microorganism that produced the oxidant as Burkholderia cenocepacia. The oxidant was produced by log phase cells, oxidized the dye 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), had a mass below 1 kD, was heat stable (121°C) and was soluble in ethanol. In a MFC with a 1000 Ω load and ABTS as a mediator, the oxidizer increased cell voltage 11 times higher than atmospheric oxygen and 2.9 times higher than that observed with ferricyanide in the cathode chamber. No increase in cell voltage was observed when no mediator was present. Organisms that produce and release oxidizers into the media may prove useful as bio-cathodes by improving the electrical output of MFCs.

Expression of leukemia/lymphoma-related factor (LRF/POKEMON) in human breast carcinoma and other cancers

The POK family of proteins plays an important role in not only embryonic development and cell differentiation, but also in oncogenesis. Leukemia/lymphoma-related factor (LRF) belongs to the POK family of transcriptional repressors and is also known as POK erythroid myeloid ontogenic factor (POKEMON), which binds to short transcripts of HIV-1 (FBI-1) and TTF-1 interacting peptide (TIP21). Its oncogenic role is known only in lymphoma, non-small cell lung carcinoma, and malignant gliomas. The functional expression of LRF in human breast carcinoma has not yet been confirmed. The aim of this study was to investigate and compare the expression of LRF in human breast cancer tissues and other human tumors. The expression of LRF mRNA transcripts and protein was observed in twenty human benign and malignant breast biopsy tissues. Expression of LRF was observed in several formalin-fixed tissues by immunohistochemistry and immunofluorescence. All malignant breast tissues expressed mRNA transcripts and protein for LRF. However, 40% and 15% benign breast biopsy tissues expressed LRF mRNA transcripts and protein, respectively. The overall expression of LRF mRNA transcripts and total protein was significantly more in malignant breast tissues than the benign breast tissues. LRF expression was also observed in the nuclei of human colon, renal, lung, hepatocellular carcinomas and thymoma tumor cells. In general, a significantly higher expression of LRF was seen in malignant tissues than in the corresponding benign or normal tissue. Further studies are warranted to determine the malignant role of LRF in human breast carcinoma.

Rare potential pitfall in endoscopic ultrasound-guided fine needle aspiration biopsy in gastric duplication cyst: a case report

BACKGROUND

Foregut duplication cyst (FDC) is rare in the adult population. It is usually an incidental finding in clinical settings. As endoscopic ultrasound-guided fine needle aspiration biopsy (EUS-FNAB) becomes a preferred and popular procedure, it is imperative for cytopathologists recognize this rare lesion and avoid the diagnostic pitfall.

CASE

A 48-year-old man presented with a 3-cm mass on the lesser curvature of the stomach with regional lymphoadenopathy. EUS-FNAB revealed abundant tenacious, viscous, mucinous material with scattered histiocytes and gastric and esophageal mucosal cells. A mucinous neoplasm was suspected, and partial sleeve gastrectomy was subsequently performed for removal of the gastric mass. The histopathologic finding was characteristic of gastric duplication cyst.

CONCLUSION

The cytologic features of FDCs may closely resemble those of mucinous neoplasms, especially with clinically elevated carcinogenic embryonic antigen and CA19-9. The abundant mutinous material with scattered mucophages can create a diagnostic challenge and pitfall. Clinical information with endoscopic findings and knowledge of FDC are important for appropriate diagnosis of mucinous lesions.

Nitrogen limited biobarriers remove atrazine from contaminated water: laboratory studies

Atrazine is one of the most frequently used herbicides. This usage coupled with its mobility and recalcitrant nature in deeper soils and aquifers makes it a frequently encountered groundwater contaminant. We formed biobarriers in sand filled columns by coating the sand with soybean oil; after which, we inoculated the barriers with a consortium of atrazine-degrading microorganisms and evaluated the ability of the barriers to remove atrazine from a simulated groundwater containing 1 mg L(-1) atrazine. The soybean oil provided a carbon rich and nitrogen poor substrate to the microbial consortium. Under these nitrogen-limiting conditions it was hypothesized that bacteria capable of using atrazine as a source of nitrogen would remove atrazine from the flowing water. Our hypothesis proved correct and the biobarriers were effective at removing atrazine when the nitrogen content of the influent water was low. Levels of atrazine in the biobarrier effluents declined with time and by the 24th week of the study no detectable atrazine was present (limit of detection<0.005 mg L(-1)). Larger amounts of atrazine were also removed by the biobarriers; when biobarriers were fed 16.3 mg L(-1) atrazine 97% was degraded. When nitrate (5 mg L(-1) N), an alternate source of nitrogen, was added to the influent water the atrazine removal efficiency of the barriers was reduced by almost 60%. This result supports the hypothesis that atrazine was degraded as a source of nitrogen. Poisoning of the biobarriers with mercury chloride resulted in an immediate and large increase in the amount of atrazine in the barrier effluents confirming that biological activity and not abiotic factors were responsible for most of the atrazine degradation. The presence of hydroxyatrazine in the barrier effluents indicated that dehalogenation was one of the pathways of atrazine degradation. Permeable barriers might be formed in-situ by the injection of innocuous vegetable oil emulsions into an aquifer or sandy soil and used to remove atrazine from a contaminated groundwater or to protect groundwater from an atrazine spill.

Acute eosinophilic myocarditis mimicking myocardial infarction

Eosinophilic myocarditis is characterized by progressive myocardial damage that results in heart failure and death. Herein, we present the case of a 54-year-old man who presented with symptoms of acute myocardial infarction. Normal coronary angiographic results and the presence of elevated levels of peripheral-blood eosinophilia prompted an endomyocardial biopsy that revealed acute eosinophilic myocarditis. The early initiation of steroid therapy resulted in the patient's substantial clinical improvement and survival. Early diagnosis of eosinophilic myocarditis and its treatment with steroid agents in some patients can lead to a favorable outcome. We discuss the challenge of diagnosing and identifying the characteristics of this variant of necrotizing eosinophilic myocarditis before the condition proves fatal.

Bio-reduction of selenite to elemental red selenium by Tetrathiobacter kashmirensis

A bacterium that detoxifies selenite by reduction to insoluble elemental red selenium was isolated from soil. The strain showed an unusually high resistance to the toxic effects of selenite by growing in media containing 64 mM selenite. 16S rRNA gene sequence alignment identified the isolate as Tetrathiobacter kashmirensis. Fatty acid analysis and morphology confirmed the identification. The isolate reduced selenite to elemental selenium under aerobic conditions only. Native gel electrophoresis of cell-free extracts revealed a band, corresponding to a molecular weight of approximately 120 kDa, that reduced selenite. In culture, the strain did not reduce selenate; however, a soluble and inducible enzyme with a molecular weight of approximately 90 kDa that reduced both selenate and nitrate was present in cell-free extracts. This organism might be useful in bioreactors designed to remove selenite from contaminated water.

Carbohydrate and ethane release with Erwinia carotovora subspecies betavasculorum--induced necrosis

Erwinia carotovora subspecies betavasculorum, also known as E. betavasculorum and Pectobacterium betavasculorum, is a soil bacterium that has the capacity to cause root rot necrosis of sugarbeets. The qualitatively different pathogenicity exhibited by the virulent E. carotovora strain and two avirulent strains, a Citrobacter sp. and an Enterobacter cloacae, was examined using digital analysis of photographic evidence of necrosis as well as for carbohydrate, ethane, and ethylene release compared with uninoculated potato tuber slices. Visual scoring of necrosis was superior to digital analysis of photographs. The release of carbohydrates and ethane from potato tuber slices inoculated with the soft rot necrosis-causing Erwinia was significantly greater than that of potato tuber slices that had not been inoculated or that had been inoculated with the nonpathogenic E. cloacae and Citrobacter sp. strains. Interestingly, ethylene production from potato slices left uninoculated or inoculated with the nonpathogenic Citrobacter strain was 5- to 10-fold higher than with potato slices inoculated with the pathogenic Erwinia strain. These findings suggest that (1) carbohydrate release might be a useful measure of the degree of pathogenesis, or relative virulence; and that (2) bacterial suppression of ethylene formation may be a critical step in root rot disease formation.

Rhizobium selenireducens sp. nov.: a selenite-reducing alpha-Proteobacteria isolated from a bioreactor

A Gram-negative, nonpigmented bacterium designated strain B1 was isolated from a laboratory bioreactor that reduced selenate to elemental red selenium (Se(0)). 16S rRNA gene-sequence alignment identified the isolate as a Rhizobium sp. belonging to the Rhizobium clade, which includes R. daejeonense, R. giardinii, R. undicola, R. larrymoorei, R. radiobacter, R. rubi, and R. vitis. R. radiobacter and R. rubi are its closest relatives as indicated by 16S rRNA gene-sequence alignments, which differ from strain B1 by 2.6% and 2.8%, respectively. Within this group, strains that show variances > 0.8% to 2.2% have been classified as different species. The major cellular fatty acids present in the B1 strain were C16:0 (1.8%), C18:0 (3.38%), 18:0 3-OH (1.6%), 18:1 omega7c (86.8%), 19:0 cycloomega8c (1.5%), and summed features 2 (3.8%) and 3 (1.2%). The large amount of 18:1 omega7c present is constant with members of this group of bacteria, but the small amounts of 16:0, 19:0 cycloomega8c, and summed feature 3 shows variance from R. radiobacter and R. rubi. The strain's phenotypic and biochemical characteristics are consistent with its placement in this genus.

Reduction of selenite to elemental red selenium by Rhizobium sp. strain B1

A bacterium that reduces the soluble and toxic selenite anion to insoluble elemental red selenium (Se(0)) was isolated from a laboratory bioreactor. Biochemical, morphological, and 16S rRNA gene sequence alignment identified the isolate as a Rhizobium sp. that is related to but is genetically divergent from R. radiobacter (syn. Agrobacterium tumefaciens) or R. rubi (syn. A. rubi). The isolate was capable of denitrification and reduced selenite to Se(0) under aerobic and denitrifying conditions. It did not reduce selenate and did not use selenite or selenate as terminal e(-) donors. Native gel electrophoresis revealed two bands, corresponding to molecular weights of approximately 100 and approximately 45 kDa, that reduced selenite. Tungsten inhibited in vivo selenite reduction, suggesting that a molybdenum-containing protein is involved in selenite reduction. This organism, or its enzymes or DNA, might be useful in bioreactors designed to remove selenite from water.

An Azospira oryzae (syn Dechlorosoma suillum) strain that reduces selenate and selenite to elemental red selenium

A bacterium that reduces the soluble selenium oxyanions, selenate and selenite, to insoluble elemental red selenium (Se(0)) was isolated from a laboratory reactor developed to remove selenate from groundwater. Gene sequence alignment of the 16S rRNA allowed identification of the isolate as Azospira oryzae. Biochemical and morphologic characterization confirm the identification. The isolate reduces selenate and selenite to Se(0) under microaerophilic and denitrifying conditions but not under aerobic conditions. It does not use selenate or selenite as terminal e(-) donors. Se oxyanion reduction causes the formation of Se nanospheres that are 0.25 +/- 0.04 microm in diameter. Nanospheres may be associated with the cells or free in the medium. The enzymatic activity associated with the reduction of selenate has a molecular mass of approximately 500 kD, and the enzymatic activity associated with the reduction of selenite has a mass of approximately 55 kD. Selenite reduction was inhibited by tungsten. The molecular masses of these activities were different from those associated with the reduction of dimethylsulfoxide, sulfate, and nitrite. This bacterium, or perhaps its enzymes or DNA, might be useful for the remediation of waters contaminated with Se oxyanions.

A (9;11)(q34;q13) translocation in a hibernoma

The diagnosis of hibernoma has historically been made by histopathologic examination and finding of characteristic brown fat cells with granular multivacuolated cytoplasm. The diagnosis of hibernoma may be complicated, however, because seemingly diagnostic cells could be mistakenly identified as lipoblasts, leading to the erroneous diagnosis of well-differentiated liposarcoma. Cytogenetic alterations in lipomatous tumors are well established and could be used for diagnostic purposes. Previous cytogenetic abnormalities reported in hibernomas have included alteration of 11q13 region. Here, we present a case of a hibernoma with a novel cytogenetic alteration involving a reciprocal translocation between 9q and 11q that was useful in establishing the final diagnosis.

Removing selenate from groundwater with a vegetable oil-based biobarrier

Vegetable oil-based permeable reactive biobarriers (PRBs) were evaluated as a method for remediating groundwater containing unacceptable amounts of selenate. PRBs formed by packing laboratory columns with sand coated with soybean oil were used. In an initial 24-week study a simulated groundwater containing 10 mg L(-1) selenate-Se was supplied to three soil columns and the selenate and selenite content of the effluent waters monitored. Two of the soil columns were effective at removing selenate and, during the final 21 weeks of the study, effluents from these columns contained almost no selenate or selenite. Almost all (95%) of the selenate removed was recovered as immobilized selenium sequestered in the solid matrix of the column. For unknown reasons, the third column failed to reduce selenate. A second study looked at the ability of PRBs to remove selenate when nitrate was present. As was done in the first study, three columns were evaluated but this time the water supplied to the columns contained 20 mg L(-1 )nitrate-N and 10 mg L(-1) selenate-Se. Nitrate quickly disappeared from the effluents of these columns and during the final 23 weeks of the study, the nitrate content of the effluent water averaged less than 0.03 microg ml(-1) nitrate-N. Selenate was also removed by these columns but at a slower rate than observed with nitrate. In the final 6 weeks of the study, about 95% of the selenate applied to the columns was removed. In situ PRBs containing soybean oil might be used to remediate groundwater contaminated with both selenate and nitrate.

Identification and characterization of an Aeromonas salmonicida (syn Haemophilus piscium) strain that reduces selenite to elemental red selenium

A bacterium that reduces toxic and mobile selenite to insoluble elemental selenium (Se0) was isolated from a laboratory scale permeable reactive biobarrier. Biochemical tests and 16S rRNA gene sequence alignment identified the isolate as Aeromonas salmonicida. Two colony types were isolated, one more resistant to selenite than the other. Both grew on agar plates containing 16 mM: selenite, although the colony diameter was reduced to 8% of controls with the small colony type and to 18% with the large colony type. Further study was done with the large colony type. In anaerobic culture, this bacterium was able to use nitrate as a term electron acceptor but not selenate or selenite. In aerobic culture, when no nitrate was present, early log phase cells removed selenite at a rate of 2.6 +/- 0.42 micromol SeO3 (-2)/mg protein/day. Reduction was retarded by 25 mM: nitrate. Mutants with a diminished ability to reduce selenite to Se0 also had a reduced ability to reduce nitrate to nitrous oxide. This bacterium, or perhaps its enzymes or DNA, might be used to remove selenite from contaminated groundwaters.

A comparison of stent-induced stenosis in coronary and peripheral arteries

BACKGROUND AND OBJECTIVES

Restenosis is a complication of interventional procedures such as angioplasty and stenting, often limiting the success of these procedures. Knowledge regarding the relative behaviour of different arteries after these procedures is limited, despite the extensive use of different vascular models. Although the results from studies using different vessels are analysed to predict the behaviour of coronary arteries and other vasculature, direct controlled comparisons between different arteries are necessary for a better understanding of the differential response to restenosis.

METHODS

This study examines the response to stenting in coronary and internal iliac arteries as characterised by intimal hyperplasia and restenosis. In a swine model of in-stent stenosis, coronary arteries exhibited higher levels of intimal hyperplasia and per cent stenosis than internal iliac arteries.

RESULTS

After normalisation for injury score, coronary arteries were found to undergo 47% more intimal hyperplasia (p<0.05), whereas per cent stenosis normalised for injury score tended to be higher (p = 0.01). Other measurements reflecting post-stenting intimal hyperplasia (maximal intimal thickness, medial area) did not exhibit significant differences between the artery groups.

CONCLUSIONS

These results show that coronary vessels are more prone to develop significant intimal hyperplasia and subsequent restenosis than internal iliac vessels. A better insight into how different arteries and arterial components behave is important in understanding and developing newer and better therapeutic measures for restenosis.

Evidence that insulin-like growth factor-1 requires protein kinase C-epsilon, PI3-kinase and mitogen-activated protein kinase pathways to protect human vascular smooth muscle cells from apoptosis

Insulin-like growth factor (IGF)-1 has been implicated in the development of occlusive vascular lesions. Although its role in vascular smooth muscle cell (VSMC) growth and migration are fairly well characterized, anti-apoptotic signals of IGF-1 in human VSMC remain largely unknown. In this study, we examined IGF-1 signals that protect human and rat VSMC from staurosporine (STAU)- and c-myc- induced apoptosis, respectively. Treatment with STAU resulted in apoptotic DNA fragmentation, phosphatidylserine externalization and cell shrinkage, but only occasional VSMC 'blebbing'. STAU-induced death and IGF-1-mediated survival were concentration dependent, while time-lapse video microscopy showed that IGF-1 inhibited c-myc-induced apoptosis by 90%. Pretreatment with mitogen-activated protein kinase/extracellular signal regulated kinase kinase (MEK) inhibitors UO126 and PD098059, or with the phosphatidylinositol 3-kinase (PI3-K) inhibitor wortmannin, reversed IGF-1-mediated human VSMC survival by 25-27% and 66%, respectively. Translocation studies showed that IGF-1 activated protein kinase C (PKC)-epsilon, but not PKC-alpha or PKC-delta, even in the presence of STAU, while pharmacological PKC inhibition (Ro-318220 or Go6976) implicated PKC-zeta or a novel PKC isozyme in IGF-1-mediated survival. Transient expression of activated PKC-epsilon but not activated PKC-zeta decreased myc-induced apoptosis in rat VSMC. In human VSMC, antisense oligodeoxynucleotides to PKC-epsilon partially reversed IGF-1-induced survival. In addition, IGF-1 elicited a mild but sustained activation of extracellular signal regulated kinase (ERK)1/2 in human VSMC that was abolished after 1 h in the presence of STAU. PKC downregulation reversed both IGF-1- and PMA-induced ERK activity, but platelet-derived growth factor (PDGF)-induced activity was unchanged. These results indicate for the first time that IGF-1 can protect human VSMC via multiple signals, including PKC-epsilon, PI3-K and mitogen-activated protein kinase pathways.

Ichthyosis uteri: a case report and review of the literature

Squamous metaplasia of endometrium is mostly manifested by morules or nodules of benign nonkeratinizing squamous cells intimately mixed with benign or malignant endometrial glands. It has been described with low-grade adenocarcinoma of the endometrium, as well as with various benign conditions, including hyperplasia, chronic endometritis, and endometrial polyps. However, extensive plaquelike, keratinizing squamous change is distinctly uncommon. To our knowledge, we describe the first case of extensive benign squamous keratinization with underlying endometrial adenocarcinoma.

Injection of innocuous oils to create reactive barriers for bioremediation: laboratory studies

In situ groundwater remediation may be achieved using stationary permeable barriers created by the injection of a substrate, such as innocuous vegetable oil, into the contaminated aquifer. The oil provides the electron donor stimulating microorganisms to degrade or sequester many contaminants. At present, little is known about the best procedures to use when injecting oil into an aquifer. In this investigation, laboratory column and sand tank studies were used as model systems to explore the effect of different injection parameters on the distribution of oil emulsions into water-saturated sand. The parameters investigated included injection pressures of 70, 1400 and 18,000 KPa; injection times of 15, 30, 60 or 120 s; and the influence of an emulsifier, polyoxyethylenesorbitan monooleate (Tween 80), upon the distribution of the injected oil. The longest injection patterns were achieved at 18,000 KPa. A pattern that was 46+/-1.8 cm long was produced with an 18,000 KPa injection for 60 s. Increasing the injection time to 120 s increased the length of the pattern by only 6.5%. Tween 80 at concentrations of 0.05% increased the width of the injection patterns but did not increase the length of the pattern. A multi-ported injection probe might be used to create in situ permeable barriers approximately 1 m wide.

Removing selenite from groundwater with an in situ biobarrier: laboratory studies

Laboratory biobarriers were evaluated for their ability to remove selenite from flowing groundwater. Microbial activity in aquifers is usually limited by substrate availability, and biobarriers stimulate microbial activity by providing a substrate; for these studies soybean oil was used. Water containing 10 mg L(-1) selenite-Se was pumped through the biobarriers for 74 days and the amount present in the effluent monitored. The amounts remained high for the first 2 weeks of the study but then declined. From day 28 until the end of the study the amount of selenite-Se in the column effluents averaged 0.20 +/- 0.04 mg L(-1), a decrease of approximately 98%. At the end of the study about half of the selenite-Se applied to the columns was recovered as immobilized selenium trapped by the biobarrier. This study suggests that biobarriers containing vegetable oil might be used as a process for removing selenite from contaminated groundwater.

Monosomy 22 as a diagnostic aid in a case of late recurrence of adult granulosa cell tumor of the ovary

Cytogenetic analysis of a case of metastatic granulosa cell tumor recurring 21 years after oophorectomy revealed monosomy 22. This anomaly, typical of granulosa cell tumor, coupled with the pathologic and immunophenotypic findings assisted in establishing the proper diagnosis of this lesion in the absence of the original histopathologic slides.

Determination of dimethylselenide and dimethyldiselenide by gas chromatography–photoionization detection

A simple method for the determination of volatile selenium compounds employing a gas chromatograph equipped with a photoionization detector is described. The method involves the direct injection of dimethylselenide (DMS) or dimethyldiselenide (DMDS) into the gas chromatograph; no derivatization of the sample was required. The photoionization detector was capable of detecting 60 pg (0.55 pmol) of DMS and 150pg (0.80pmol) DMDS. Sensitivity was 10-50 times greater with DMS and 4-20 times greater with DMDS when the photoionization detector was employed than when the flame ionization detector was employed.

Calphostin C as a rapid and strong inducer of apoptosis in human coronary artery smooth muscle cells

Vascular smooth muscle cells (VSMCs) play a major role in the development of atherosclerotic and restenotic lesions. The apoptotic process has been implicated in the development of this pathology. In this study, we characterized the induction of apoptosis by calphostin C (CC), a protein kinase C (PKC) inhibitor, in primary human coronary artery smooth muscle cells in the presence and absence of insulin-like growth factor-I (IGF-I). Additionally, we investigated the signal transduction pathways important for IGF-I mediated protection. Calphostin C induced apoptosis, as measured by terminal deoxy-UTP nick-end labeling (TUNEL), in a time- and dose-dependent manner, approaching 20% within 6 h of 50 nM calphostin C treatment. The amount of apoptosis increased to 44.58+/-8.08%, 47.54+/-1.66% and 78.1+/-11.9% after 8, 10 and 12 h of treatment, respectively (p<0.01 vs. control). IGF-I offered significant protection (p<0.05) at 8 and 10 h of treatment (60.6% and 52.5% protection, respectively). DNA ELISA confirmed the apoptotic effect of calphostin C and the protective effect of IGF-I. After 6 h of calphostin C treatment, DNA ELISA revealed 11.20+/-1.53 fold greater apoptosis as compared to baseline values. IGF-I treatment offered a level of protection of 46.6% as measured by DNA ELISA (p=0.06). Apoptosis was further qualitatively confirmed by time-lapse video microscopy and scanning electron microscopy. Interestingly, inhibitors of phosphatidylinositol-3-kinase (PI-3-K), p38 and extracellular regulated kinase (ERK) activation significantly (p<0.05 vs. calphostin C only treatment) increased apoptosis when used in conjunction with calphostin C. Inhibitors of phospatidylinositol-3-kinase and ERK activation reversed IGF-I protection. However, the p38 inhibitor SB203580 failed to reverse IGF-I protection. This study characterized an apoptotic system for human coronary artery smooth muscle cells offering a rapid and strong induction of programmed cell death (PCD) that remains responsive to the survival effects of IGF-I. Studies utilizing this system may prove useful in understanding the apoptotic response of VSMCs in the arterial wall.

Accumulation of nitrite in denitrifying barriers when phosphate is limiting

Permeable in situ denitrifying barriers can remove nitrate from groundwater. Barriers may be constructed by filling an excavated area with a porous mixture of sand, fine gravel, and substrate or by the injection of a nonaqueous phase substrate into an aquifer. The substrate stimulates the development of a denitrifying microbial community by providing an electron donor. The objective of this study was to determine the ability of denitrifying barriers to function under low-phosphate conditions. Sand columns injected with a soybean oil emulsion were used as laboratory models of denitrifying barriers. When a natural groundwater containing 17 mg l(-1) nitrate-N and 0.009 mg l(-1) phosphate-P was pumped through the columns, only a small amount of nitrate was removed from the water and, in some effluent fractions, 52% to 88% of the influent nitrate had converted to nitrite. Nitrite also accumulated when the phosphate concentration of the groundwater was increased to 0.040 or 0.080 mg l(-1) phosphate-P. Only when a 0.160 mg l(-1) phosphate-P supplement was added to the groundwater was there a loss of nitrate without a large accumulation of nitrite. The addition of solid calcium phosphate or rock phosphate to the sand columns was found to provide adequate phosphate for denitrification in short-term studies. These studies point out the need to ensure that adequate phosphate is present in denitrifying barriers especially when such barriers are used beneath phosphate-binding soils.

Comparison of vascular smooth muscle cell apoptosis and fibrous cap morphology in symptomatic and asymptomatic carotid artery disease

The biological cascades that lead to carotid plaque disruptions and symptoms are largely unknown. Certain cellular events within the plaque might be responsible for destabilizing the plaque, though the popular belief is that the plaque size is directly related to symptoms. The aim of our study was to assess the morphology of the fibrous cap and apoptosis in the plaque and compare these two pathological features in symptomatic and asymptomatic carotid artery disease. Our work was carried out in plaques obtained following carotid endarterectomy performed for symptomatic disease (including hemispheric transient ischemic attacks, amaurosis fugax, or stroke) or asymptomatic high-grade severe stenosis. Scion images of Gomori's stained sections were used to measure fibrous cap thickness and area. TUNEL assay was performed to assess the extent of apoptosis. The results indicated that the area of the fibrous cap did not significantly correlate with the presence of symptoms. There was a higher percentage of apoptotic nuclei and the thinner fibrous cap in symptomatic plaques than in asymptomatic plaques. This finding suggests that these factors might be involved in destabilizing plaque, causing rupture and leading to symptomatic carotid disease.