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Background. Epidermal growth factor (EGF) and EGF-regulated processes play an important role in steroid signal transduction. Comparative analysis of EGF and steroid receptor expression and the sensitivity of early stages of proliferation induction, such as activation of phospholipid turnover to EGF and steroids, may provide a useful new approach to characterizing the sensitivity of endometrial cancer to hormone therapy. Methods. Progesterone (PR), estradiol (ER), and EGF receptor (EGFR) content was measured by radioligand competitive methods in surgically excised tumors from 26 patients with primary endometrial cancer. In short term cell cultures isolated from 11 of these tumors, the influence of a 10-minute treatment with 10-"M EGF either alone or combined with 10-"M progesterone on 3ZP-in~orporation into phospholipids was studied. Phospholipids were fractionated by thin-layer chromatography and were located by autoradiography, and quantification of the labeled compounds was made by densitometric scanning of the autoradiograms. Results. Epidermal growth factor receptor was found in 15 of 26 (58%) endometrial cancer samples. Eighty-two percent of the tumors studied contained PR, and 81% contained ER. No significant correlations were revealed between EGFR and ER/PR status or concentration. Epidermal growth factor stimulated 32P-incorporation by more From the *Laboratory of Clinical Biochemistry, the tDepartment of Pathologic Anatomy, and the $Laboratory of Tumor Biochemistry, the Cancer Research Center of the Russian Academy of Medical Sciences, Moscow, Russia. Supported by grant MVB 000 from the International Science Foundation and by grant 93-04-6442 from the Russian Basic Science Foundation.

A large number of papers have been published on the magnetic field effect (MFE) in various kinds of chemical which were detected mainly by the transient absorption meth0d~9~ and product analy~is.~,~ The radical pair model of CIDNP9$Io has been proposed for the mechanism of this magnetic field dependence and was confirmed by several techniques. For the photoreduction of quinones in sodium dodecyl sulfate (SDS) micellar solutions, we found that the ESR transitions of both the SDS radical and the semiquinone radical affect the yield of a product that is produced only from the SDS radical (i.e. spin adduct).” This is direct evidence of the RP model for this kind of magnetic field dependence. As another evidence of the RP model, Closs et a1.I2 and McLauchlan et al.I3 have explained a new-type of CIDEP found by Sakaguchi et al.I4 for a similar system with the interaction in the RP. Because with our method the ESR spectrum of the RP is traced by the change of the final-product yield, we call this method product-yield-detected ESR,l5%l6 or PYESR in short. Since these spin-dependent phenomena are deeply concerned with the relation between the chemical bond and the spin correlation of the two unpaired electrons from which a new bond is created,I7 these are undoubtedly an important theme of the basic chemistry. In the PYESR technique, we usually use the spin trapping meth~d’~.’~ to separate the escape product as a spin adduct from the cage product, and also to determine the yield by ESR with which in-situ observation is easy. Since PYESR is also possible by using the HPLC method,20 other techniques such as NMR should be potentially applicable. As a similar technique to detect the ESR of a spin pair,21 the optically-detected ESR technique has been well-known in solid-state and subsequently applied to solution chemi~try.~~-~~ These studies have been successful in elucidating the structure of ionic species in the irradiated sy~tems,~~,~~,~~ the reaction mechanism of the photosynthetic system,27 and the dynamics of an ion pair in a photolytically ionized system.28 The main difference with our method is that we observe the yield of a final product and the

SPECIFIC AIMSThe Nogo gene encodes for an integral protein responsible for the neurite inhibition properties in myelin. In this study we analyzed the mRNA expression pattern of the Nogo genes (Nogo...

Three pulse sequences have been employed for laser and microwave-pulse irradiation in the pulse mode product-yield-detected ESR technique to detect the dynamical feature of transient radical pair. In this method, the decrease in spin adduct yield as functions of delay times for irradiation/termination of the microwave pulse after the laser pulse are simulated with the Runge-Kutta method for a detailed reaction model to obtain the rate constants of cage product formation, escape of the radical pair, as well as the hydrogen abstraction reaction. As the representative reaction systems, photoreduction of anthraquinone, anthraquinone-2-sulfonate, and benzophenone in SDS micellar solution were employed. Effects of cyclohexene, added as a hydrogen donor, NaCl and Ethanol, added to change the microviscosity of micelle, on these reaction rate constants have been tested.

Excitotoxic brain lesions, such as stroke and epilepsy, lead to increasing destruction of neurons hours after the insult. The deadly cascade of events involves detrimental actions by free radicals and the activation of proapoptotic transcription factors, which finally result in neuronal destruction. Here, we provide direct evidence that the nutritionally essential trace element selenium has a pivotal role in neuronal susceptibility to excitotoxic lesions. First, we observed in neuronal cell cultures that addition of selenium in the form of selenite within the physiological range protects against excitotoxic insults and even attenuates primary damage. The neuroprotective effect of selenium is not directly mediated via antioxidative effects of selenite but requires de novo protein synthesis. Gel shift analysis demonstrates that this effect is connected to the inhibition of glutamate-induced NF-kappaB and AP-1 activation. Furthermore, we provide evidence that selenium deficiency in vivo results in a massive increase in susceptibility to kainate-induced seizures and cell loss. These findings indicate the importance of selenium for prevention and therapy of excitotoxic brain damage.

Let ?n be a linear hyperplane arrangement in ?n. We define two corresponding posetsGk(?n andVk(?n) of oriented matroids, which approximate the GrassmannianGk(?n) and the Stiefel manifoldVk(?n). The basic conjectures are that the "OM-Grassmannian"Gk(?n) has the homotopy type ofGk(?n), and that the "OM-Stiefel bundle" Δ?: ΔVk(?n) ? ΔGk(?n) is a surjective map. These conjectures can be proved in some cases: we survey the known results and add some new ones. The conjectures fail if they are generalized to nonrealizable oriented matroids ?n.

A convenient preparation of α- and β-anomers of 1,5-di-O-benzoyl-2,3-dideoxy-3-fluoro-D-erythro-pentofuranose is described. Each anomer is studied as the glycosylating agent in the reaction with bis-trimethylsilylated thymine in the presence of trimethylsilyl triflate. Under optimum conditions, 2',3'-dideoxy-3'-fluorothymidine (FLT) and its α-anomer are isolated in 64 and 25% yields, respectively

We investigated the role of technetium-99m (99mTc) sestamibi cardiac imaging and dobutamine echocardiography in detecting myocardial viability early after acute myocardial infarction.Nineteen patients (mean age 52 +/- 10 years) underwent coronary angiography, low-dose dobutamine echocardiography and rest 99mTc sestamibi imaging within 10 days of myocardial infarction. All patients were revascularized. Resting echocardiogram was repeated 8 months later to evaluate segmental functional recovery.Sixty-one of 108 akinetic or dyskinetic segments at baseline showed functional recovery after revascularization. Sensitivity in predicting segmental functional recovery was 87% for sestamibi imaging and 66% for dobutamine echocardiography (p0.001), while specificity and accuracy were comparable. Sestamibi activity was the strongest predictor of segmental functional recovery (p0.001).Dobutamine echocardiography predicts functional recovery after myocardial infarction. However, sestamibi imaging is useful to identify patients with dysfunctional segments without contractile reserve which may benefit by revascularization.

In N1E-115 cells, neurite retraction induced by neurite remodelling factors such as lysophosphatidic acid, sphingosine 1-phosphate and semaphorin 3A require the activity of phosphatidylinositol 4-phosphate 5-kinases (PIP5Ks). PIP5Ks synthesise the phosphoinositide lipid second messenger phosphatidylinositol(4,5)bisphosphate [PtdIns(4,5)P₂], and overexpression of active PIP5K is sufficient to induce neurite retraction in both N1E-115 cells and cerebellar granule neurones. However, how PIP5Ks are regulated or how they induce neurite retraction is not well defined. Here, we show that neurite retraction induced by PIP5Kβ is dependent on its interaction with the low molecular weight G protein Rac. We identified the interaction site between PIP5Kβ and Rac1 and generated a point mutant of PIP5Kβ that no longer interacts with endogenous Rac. Using this mutant, we show that Rac controls the plasma membrane localisation of PIP5Kβ and thereby the localised synthesis of PtdIns(4,5)P₂ required to induce neurite retraction. Mutation of this residue in other PIP5K isoforms also attenuates their ability to induce neurite retraction and to localise at the membrane. To clarify how increased levels of PtdIns(4,5)P₂ induce neurite retraction, we show that mutants of vinculin that are unable to interact with PtdIns(4,5)P₂, attenuate PIP5K- and LPA-induced neurite retraction. Our findings support a role for PtdIns(4,5)P₂ synthesis in the regulation of vinculin localisation at focal complexes and ultimately in the regulation of neurite dynamics.

A series of 3'-deoxy-3'-fluoro- and 2'-azido-2',3'-dideoxy-3'-fluoro-D-ribofuranosides of natural heterocyclic bases have been synthesized with the use of universal carbohydrate precursors, viz., 1-O-acetyl-2,5-di-O-benzoyl-3-deoxy-3-fluoro-D-ribofuranose and methyl 2-azido-5-O-benzoyl-2,3-dideoxy-3-fluoro-beta-D-ribofuranoside, respectively. The cytostatic and antiviral activity of the compounds was evaluated against a variety of tumor cell lines and DNA/RNA viruses, respectively. As the most active compound, from both a cytostatic and antiviral activity viewpoint, emerged 3'-deoxy-3'-fluoroadenosine. It inhibited the proliferation of some tumor cell lines (i.e. murine leukemia L1210 and human T-lymphocyte MT-4) at a concentration of 0.2-2 micrograms/mL, and proved inhibitory to the replication of positive-stranded RNA viruses (i.e. polio, Coxsackie, Sindbis, Semliki forest), double-stranded RNA viruses (i.e. reo), and some DNA viruses (i.e. vaccinia) at a concentration of 1-4 micrograms/mL, which is well below the cytotoxicity threshold (40 micrograms/mL).

A large number of papers have been published on the magnetic field effect (MFE) in various kinds of chemical which were detected mainly by the transient absorption meth0d~9~ and product analy~is.~,~ The radical pair model of CIDNP9$Io has been proposed for the mechanism of this magnetic field dependence and was confirmed by several techniques. For the photoreduction of quinones in sodium dodecyl sulfate (SDS) micellar solutions, we found that the ESR transitions of both the SDS radical and the semiquinone radical affect the yield of a product that is produced only from the SDS radical (i.e. spin adduct).” This is direct evidence of the RP model for this kind of magnetic field dependence. As another evidence of the RP model, Closs et a1.I2 and McLauchlan et al.I3 have explained a new-type of CIDEP found by Sakaguchi et al.I4 for a similar system with the interaction in the RP. Because with our method the ESR spectrum of the RP is traced by the change of the final-product yield, we call this method product-yield-detected ESR,l5%l6 or PYESR in short. Since these spin-dependent phenomena are deeply concerned with the relation between the chemical bond and the spin correlation of the two unpaired electrons from which a new bond is created,I7 these are undoubtedly an important theme of the basic chemistry. In the PYESR technique, we usually use the spin trapping meth~d’~.’~ to separate the escape product as a spin adduct from the cage product, and also to determine the yield by ESR with which in-situ observation is easy. Since PYESR is also possible by using the HPLC method,20 other techniques such as NMR should be potentially applicable. As a similar technique to detect the ESR of a spin pair,21 the optically-detected ESR technique has been well-known in solid-state and subsequently applied to solution chemi~try.~~-~~ These studies have been successful in elucidating the structure of ionic species in the irradiated sy~tems,~~,~~,~~ the reaction mechanism of the photosynthetic system,27 and the dynamics of an ion pair in a photolytically ionized system.28 The main difference with our method is that we observe the yield of a final product and the

The oxidation of methyl 5-O- benzyl-3(2)-deoxy-3(2)-fluoro- α- d - pentofuranosides with dimethyl sulfoxide-acetic (trifluoroacetic) anhydride was accompanied by epimerization at the carbon atom bearing a fluoro function, resulting in the formation of the corresponding 2- or 3-keto derivatives as mixtures of two epimers in high combined yield. Reduction of a mixture of the erythro / threo epimeric 2-keto sugars (isolated as stable hydrates) with sodium borohydride in benzene-ethanol proceeded stereoselectively leading to the formation of 3-deoxy-3-fluoro ribo and lyxo-furanosides, respectively. In the case of the ribo and arabino epimers of the 3-keto sugar (isolated as free ketones), reduction stereoselectivity of the former was > 95% for the 2-deoxy-2-fluoro ribo sugar, whereas a ca. 3:1 lyxo / arabino ratio of products was obtained for the latter. Treatment of a mixture of the 2-epimeric 3-keto sugars with triethylamine in carbon tetrachloride at room temperature for 3–5 h afforded the 2-deoxy-2-fluoro ribo ketone (ca. 90%). The synthesis of 1-O- acetyl-2,5-di -O- benzoyl-3-deoxy-3-fluoro- α,β- d - lyxofuranose (8) and 1-O- acetyl-3,5-di -O- benzoyl-2-deoxy-2-fluoro -β- d - ribofuranose (16) and their use as glycosylating agents for bis-trimethylsilylated N6-benzoyladenine is described.

2-Deoxy-2-sulfenyl- arabino -α-nucleosides and 2-deoxy-2-sulfenyl- ribo -β-nucleosides were obtained with excellent stereoselectivity from 1-thio- ribo - and 1-thio- arabino -glycosides under Mitsunobu conditions.

BACKGROUND: This study evaluated the prognostic value of combined assessment of left ventricular (LV) function and regional myocardial thallium activity in patients with nonrecent myocardial infarction and LV dysfunction. METHODS AND RESULTS: Eighty-two patients with previous myocardial infarction (>8 weeks) and echocardiographic evidence of LV dysfunction underwent thallium-201 rest-redistribution tomography and cardiac catheterization. During the follow-up period (mean 25 months) there were 18 cardiac events (14 deaths and 4 nonfatal myocardial infarctions). Multivariate Cox regression analysis on clinical, angiographic, and thallium variables showed that the number of echocardiographic dysfunctional segments with preserved thallium uptake (> or =50% of peak activity; chi-square 11.03; p

AIM:The aim of this study was to evaluate the role of 18F fluorodeoxyglucose-positron emission tomography (FDG-PET), differentiated thyroid carcinoma (DTC) treated with therapeutic (131)I because of elevated thyroglobulin (Tg) levels during follow up. The results of FDG-PET/CT were compared with post-therapy (131)I whole body scan (131I-t-WBS) and Tg at short term follow up. METHODS:Forty-five patients with DTC underwent a new therapeutic (131I) administration based upon Tg values >1.5 ng/mL. All patients underwent (131I-t-WBS) 5-7 days after 131I therapy. A few days before 131I administration, a FDG-PET scan was performed in all patients. FDG-PET/CT was considered positive (PET+) when at least one abnormal focus of FDG uptake was found; likewise, 131I-t-WBS was considered positive(WBS+) when at least on abnormal focus of uptake was found. Assessment of short-term response to radioiodine was performed by measuring Tg values. RESULTS:FDG-PET/CT was positive in 32 patients, 23 of which had positive 131I-t-WBS and negative in 13, 8 of which had a negative 131I-t-WBS. Overall agreement was 69%. Tg values were significantly higher in FDG-PET/CT positive (502+/-1 027 ng/mL) than in FDG-PET/CT negative patients (57+/-94 ng/mL). A significant difference emerged between 131I-t-WBS positive (561 +/- 1 086 ng/mL) and 131I-t-WBS negative (65+/- 120 ng/mL) findings. In these 45 patients Tg normalized in 36%, was reduced by at least 50% in 24% and remained unchanged in the remaining 40%. Overall, at short-term follow-up, Tg values normalized in 77% of the 13 patients with negative FDG-PET/CT and in 19% of the 32 patients with positive FDG-PET/CT. CONCLUSION:FDG-PET/CT is a powerful and useful tool for assessing patients with DTC. it can provide additional information in those patients with high Tg at follow-up and eligible for 131I therapy. A negative FDG-PET/CT could also represent a prognostic tool combined with serum Tg testing a short term follow-up.

This study evaluated the incremental prognostic value of 201TI reinjection imaging over clinical, exercise and thallium stress-redistribution data in patients with previous myocardial infarction and left ventricular dysfunction. METHODS: Thallium-201 reinjection after stress-redistribution SPECT was performed in 104 consecutive patients with a first Q-wave myocardial infarction (> 8 wk) and left ventricular ejection fraction < or = 40%. Follow-up data (mean 22 mo) were available for 98 patients; 16 patients underwent early revascularization procedures within 3 mo after exercise testing and were not considered for the analysis. RESULTS: During follow-up there were 13 hard events (cardiac death and myocardial infarction) and 11 soft events (coronary revascularization procedures > 3 mo after thallium imaging). With multivariate Cox regression analysis, the sum of defects at stress-redistribution imaging that were reversible or moderate irreversible after reinjection was a powerful predictor of subsequent events. The addition of thallium reinjection imaging data significantly improved the prognostic power of clinical, exercise and stress-redistribution data for the occurrence of hard events (p < 0.01). CONCLUSION: In patients with previous myocardial infarction and left ventricular dysfunction, thallium reinjection imaging provides incremental prognostic information over those obtained from conventional stress-redistribution imaging.

The phosphatidylinositol 3-kinase (PI3K)/Akt signalling pathway plays a major role in the regulation of breast cancer growth and survival, but the clinical value of its components in human tumours is unclear.PI3K was analysed using Western blotting with monoclonal antibodies to the p85 subunit in tumour and adjacent mammary gland samples from 33 breast cancer patients. Activated Akt1 (pAkt1) expression was quantified in 46 sample pairs by a direct sandwich ELISA assay.Tumour PI3K expression was increased in 79% of the investigated sample pairs and was not associated with the main clinico-pathological features. Only 49% of breast cancers had increased pAkt1, but the frequency of its elevation was positively associated with tumour size and histological grade, and controversially related to estrogen and progesterone receptor status.Increased PI3K but not pAkt1, expression appears to be a widespread feature of human breast cancer indicating the different roles of the two components of one signalling system.

Oxidative brain damage, such as excitotoxicity and stroke, leads to primary neuronal destruction. The primary damage is further potentiated by macrophages and microglial cells, which are attracted and invade into the zone of damage resulting in secondary neuronal death. Since the essential trace element selenium has anti-inflammatory properties, we analyzed the effects of selenium on these inflammatory cells. Here, we show that the essential trace element selenium abrogates the stress-induced migration of microglial cells. Thus, the antimigratory effects of selenium may attenuate the secondary cell death cascade by preventing microglial invasion.

Autotaxin is a secreted cell motility-stimulating exo-phosphodiesterase with lysophospholipase D activity that generates bioactive lysophosphatidic acid. Lysophosphatidic acid has been implicated in various neural cell functions such as neurite remodeling, demyelination, survival and inhibition of axon growth. Here, we report on the in vivo expression of autotaxin in the brain during development and following neurotrauma. We found that autotaxin is expressed in the proliferating subventricular and choroid plexus epithelium during embryonic development. After birth, autotaxin is mainly found in white matter areas in the central nervous system. In the adult brain, autotaxin is solely expressed in leptomeningeal cells and oligodendrocyte precursor cells. Following neurotrauma, autotaxin is strongly up-regulated in reactive astrocytes adjacent to the lesion. The present study revealed the cellular distribution of autotaxin in the developing and lesioned brain and implies a function of autotaxin in oligodendrocyte precursor cells and brain injuries.

Within a recent study on the vibrissae motor performance after facial nerve repair in strains of blind (SD/RCS) and sighted (SD) rats we found that, despite persisting myotopic disorganization in the facial nucleus, the blind animals fully restored vibrissal whisking. Here we searched for morphological substrates of better recovery in the regenerating motoneurons and in the cerebral motor cortex. Expression analyses of the neurite growth-related proteins f-actin, neuronal class III beta-tubulin and plasticity-related gene-1, and stereological estimates of growth cone densities revealed a more vigorous regenerative response in the proximal nerve stump of blind SD/RCS rats compared with SD animals at 5-7 days after buccal nerve transection. Using c-Fos immunoreactivity as a marker for neuronal activation, we found that the volume of the cortex acutely responding to nerve transection (facial muscles reactive volume, FMRV) in both hemispheres of intact sighted rats was twofold smaller than that measured in blind animals. One month after transection and suture of the right facial nerve (FFA) we found a twofold increase in the FMRV in both rat strains compared with intact animals. The FMRV in SD/RCS animals, but not in SD rats, returned to the values in intact rats 2 months after FFA. Our findings suggest that enhanced plasticity in the CNS and an augmented regenerative response of the injured motoneurons contribute to better functional recovery in blind rats.

Inhibitors of histone deacetylases are promising compounds for the treatment of cancer but have not been systematically explored in malignant brain tumors. Here, we characterize the benzamide MS-275, a class I histone deacetylase inhibitor, as potent drug for experimental therapy of glioblastomas. Treatment of four glioma cell lines (U87MG, C6, F98, and SMA-560) with MS-275 significantly reduced cell growth in a concentration-dependent manner (IC90, 3.75 μmol/L). Its antiproliferative effect was corroborated using a bromodeoxyuridine proliferation assay and was mediated by G0-G1 cell cycle arrest (i.e., up-regulation of p21/WAF) and apoptotic cell death. Implantation of enhanced green fluorescent protein–transfected F98 glioma cells into slice cultures of rat brain confirmed the cytostatic effect of MS-275 without neurotoxic damage to the organotypic neuronal environment in a dose escalation up to 20 μmol/L. A single intratumoral injection of MS-275 7 days after orthotopic implantation of glioma cells in syngeneic rats confirmed the chemotherapeutic efficacy of MS-275 in vivo. Furthermore, its propensity to pass the blood-brain barrier and to increase the protein level of acetylated histone H3 in brain tissue identifies MS-275 as a promising candidate drug in the treatment of malignant gliomas. [Mol Cancer Ther 2006;5(5):1248–55]

Phospholipid hydroperoxide glutathione peroxidase (GPx4) is a selenocysteine-containing enzyme, and three different isoforms (cytosolic, mitochondrial, and nuclear) originate from the GPx4 gene. Homozygous GPx4-deficient mice die in utero at midgestation, since they fail to initiate gastrulation and do not develop embryonic cavities. To investigate the biological basis for embryonic lethality, we first explored expression of the GPx4 in adult murine brain and found expression of the protein in cerebral neurons. Next, we profiled mRNA expression during the time course of embryogenesis (embryonic days 6.5-17.5 (E6.5-17.5)) and detected mitochondrial and cytosolic mRNA species at high concentrations. In contrast, the nuclear isoform was only expressed in small amounts. Cytosolic GPx4 mRNA was present at constant levels (about 100 copies per 1000 copies of glyceraldehyde-3-phosphate dehydrogenase mRNA), whereas nuclear and mitochondrial isoforms were down-regulated between E14.5 and E17.5. In situ hybridization indicated expression of GPx4 isoforms in all developing germ layers during gastrulation and in the somite stage in the developing central nervous system and in the heart. When we silenced expression of GPx4 isoforms during in vitro embryogenesis using short interfering RNA technology, we observed that knockdown of mitochondrial GPx4 strongly impaired segmentation of rhombomeres 5 and 6 during hindbrain development and induced cerebral apoptosis. In contrast, silencing expression of the nuclear isoform led to retardations in atrium formation. Taken together, our data indicate specific expression of GPx4 isoforms in embryonic brain and heart and strongly suggest a role of this enzyme in organogenesis. These findings may explain in part intrauterine lethality of GPx4 knock-out mice.