Showing papers by "University of Naples Federico II published in 1999"

Control of pain initiation by endogenous cannabinoids

Abstract: The potent analgesic effects of cannabis-like drugs and the presence of CB1-type cannabinoid receptors in pain-processing areas of the brain and spinal cord, indicate that endogenous cannabinoids such as anandamide may contribute to the control of pain transmission within the central nervous system (CNS). Here we show that anandamide attenuates the pain behaviour produced by chemical damage to cutaneous tissue by interacting with CB1-like cannabinoid receptors located outside the CNS. Palmitylethanolamide (PEA), which is released together with anandamide from a common phospholipid precursor, exerts a similar effect by activating peripheral CB2-like receptors. When administered together, the two compounds act synergistically, reducing pain responses 100-fold more potently than does each compound alone. Gas-chromatography/mass-spectrometry measurements indicate that the levels of anandamide and PEA in the skin are enough to cause a tonic activation of local cannabinoid receptors. In agreement with this possibility, the CB1 antagonist SR141716A and the CB2 antagonist SR144528 prolong and enhance the pain behaviour produced by tissue damage. These results indicate that peripheral CB1-like and CB2-like receptors participate in the intrinsic control of pain initiation and that locally generated anandamide and PEA may mediate this effect.

Effects of vinorelbine on quality of life and survival of elderly patients with advanced non-small-cell lung cancer

Abstract: BACKGROUND Vinorelbine, a semisynthetic vinca alkaloid, represents a well-tolerated treatment for elderly patients with advanced non-small-cell lung cancer (NSCLC). We explored the quality of life (QoL) of such patients in a multicenter randomized trial that compared vinorelbine treatment with supportive care alone. METHODS Eligible patients were 70 years of age or older, had stage IV or IIIB NSCLC that was ineligible for radiotherapy, and had a performance status of 0-2 (a status of fully active to a status of capable of all self-care but unable to work). Vinorelbine was given intravenously on days 1 and 8 of a 21-day treatment cycle, for a total of six cycles. QoL was evaluated with European Organization for Research and Treatment of Cancer questionnaires QLQ-C30 and QLQ-LC13, and the QoL data were analyzed by fitting a linear mixed model for each QoL scale. Survival curves were plotted and were compared with the Mantel-Haenszel test. Relative hazards of death and 95% confidence intervals (CIs) were estimated by the Cox model. RESULTS Investigators, blinded to the results, stopped the trial early because of a low enrollment rate. (From April 1996 to November 1997, 191 of the 350 targeted patients were randomly assigned.) Data from 161 patients have been analyzed. Vinorelbine-treated patients scored better than control patients on QoL functioning scales, and they reported fewer lung cancer-related symptoms but reported worse toxicity-related symptoms. There was a statistically significant (two-sided P = .03) survival advantage for patients receiving vinorelbine; median survival increased from 21 to 28 weeks in the vinorelbine-treated group. The relative hazard of death for vinorelbine-treated patients was 0.65 (95% CI = 0.45-0.93). CONCLUSION Vinorelbine improves survival of elderly patients with advanced NSCLC and possibly improves overall QoL.

Nitric oxide as a signaling molecule in the vascular system: an overview.

Abstract: In retrospect, basic research in the fields of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) during the past two decades appears to have followed a logical course, beginning with the findings that NO and cGMP are vascular smooth muscle relaxants, that nitroglycerin relaxes smooth muscle by metabolism to NO, progressing to the discovery that mammalian cells synthesize NO, and finally the revelation that NO is a neurotransmitter mediating vasodilation in specialized vascular beds. A great deal of basic and clinical research on the physiologic and pathophysiologic roles of NO in cardiovascular function has been conducted since the discovery that endothelium-derived relaxing factor (EDRF) is NO. The new knowledge on NO should enable investigators in this field to develop novel and more effective therapeutic strategies for the prevention, diagnosis, and treatment of numerous cardiovascular disorders. The goal of this review was to highlight the early research that led to our current understanding of the pathophysiologic role of NO in cardiovascular medicine. Furthermore, we discussed the possible mechanism of some drugs interfering with NO signaling cascade.

Impaired retinal function and vitamin A availability in mice lacking retinol-binding protein

Abstract: Retinol-binding protein (RBP) is the sole specific transport protein for retinol (vitamin A) in the circulation, and its single known function is to deliver retinol to tissues Within tissues, retinol is activated to retinoic acid, which binds to nuclear receptors to regulate transcription of >300 diverse target genes In the eye, retinol is also activated to 11-cis-retinal, the visual chromophore We generated RBP knockout mice (RBP(-/-)) by gene targeting These mice have several phenotypes Although viable and fertile, they have reduced blood retinol levels and markedly impaired retinal function during the first months of life The impairment is not due to developmental retinal defect Given a vitamin A-sufficient diet, the RBP(-/-) mice acquire normal vision by 5 months of age even though blood retinol levels remain low Deprived of dietary vitamin A, vision remains abnormal and blood retinol declines to undetectable levels Another striking phenotype of the mutant mice is their abnormal retinol metabolism The RBP(-/-) mice can acquire hepatic retinol stores, but these cannot be mobilized Thus, their vitamin A status is extremely tenuous and dependent on a regular vitamin A intake Unlike wild-type mice, serum retinol levels in adult RBP(-/-) animals become undetectable after only a week on a vitamin A-deficient diet and their retinal function rapidly deteriorates Thus RBP is needed for normal vision in young animals and for retinol mobilization in times of insufficient dietary intake, but is otherwise dispensable for the delivery of retinol to tissues

Persistence of increased cardiovascular risk in patients with Cushing's disease after five years of successful cure.

Abstract: Patients with Cushing's disease (CD) mainly die because of cardiovascular accidents. The aim of this study was to evaluate whether patients with CD still have increased cardiovascular risk and suffer from premature atherosclerosis once cured. Fifteen patients cured from CD for a long term period (5 yr), 30 sex-and age-matched controls, and 30 body mass index (BMI)-matched controls were included in this study. BMI; waist to hip ratio (WHR); systolic (SBP) and diastolic (DBP) blood pressures; serum total, low density lipoprotein (LDL), and high density lipoprotein (HDL) cholesterol; serum triglycerides, fibrinogen, and lipoprotein(a) levels; prothrombin time; activated partial thromboplastine time; and basal and glucose load-stimulated insulin and glucose levels were measured in patients and controls. By echo-Doppler ultrasonography, the intima media thickness (IMT), systolic and diastolic media-media distances, blood systolic (SPV) and diastolic (DPV) peak velocity, systolic (SLD) and diastolic (DLD) lumen diameter, and distensibility coefficient (DC) were measured at both common carotid arteries where the presence, size, and location of atherosclerotic plaques were also evaluated. Compared with a sex- and age-matched control population, CD patients had BMI (P < 0.001), WHR (P < 0.001), SBP (P < 0.005), DBP (P < 0.05), fasting glucose (P < 0.001) and insulin (P < 0.05), glucose load-stimulated glucose and insulin levels (P < 0.05), total cholesterol (P < 0.05), LDL cholesterol (P < 0.01), fibrinogen (P < 0.01), and lipoprotein(a) (P < 0.05) levels higher and HDL cholesterol levels (P < 0.05) lower than controls. At ultrasonography, in the patients, IMT (P < 0.05), SPV (P < 0.05) and DPV (P < 0.001) were significantly increased whereas SLD (P < 0.001), DLD (P < 0.001), and DC (P < 0.05) were significantly decreased compared to controls. In addition, CD patients had higher WHR (P < 0.05), DBP (P < 0.05), glucose load-stimulated glucose and insulin levels (P < 0.05), and fibrinogen levels (P < 0.01) and lower HDL cholesterol (P < 0.05) levels than BMI-matched controls. At ultrasonography, increased common carotid arteries IMT (P < 0.05) and DPV (P < 0.05) and decreased DLD (P < 0.05) and DC (P < 0.05) were measured in patients compared to those in BMI-matched controls. Atherosclerotic plaques were found in 26.7% of patients, in none of the sex- and age-matched controls, and in 3.3% of the BMI-matched controls. In CD patients, a significant correlation was found between both WHR and fasting serum insulin levels and DBP (r = 0.52 and r = 0.55; P < 0.05), triglycerides levels (r = 0.56 and r = 0.77; P < 0.05), and IMT (r = 0.64 and r = 0.56; P < 0.05). Right (r = -0.70; P < 0.005) and left (r = -0.65; P < 0.01) DC were inversely correlated to the duration of CD in the patient group. At the multiple regression analysis, WHR was the best predictor of fasting insulin levels (beta = 0.77; P < 0.05), and vice versa, fasting insulin level was the best predictor of WHR (beta = 1.20; P < 0.05). In conclusion, patients cured from CD for a long term period have a high prevalence of atherosclerosis and maintain increased several cardiovascular risk factors of the active disease, probably due to a residual abdominal obesity and/or insulin resistance syndrome.

Product Distribution from Pyrolysis of Wood and Agricultural Residues

Abstract: The pyrolysis characteristics of agricultural residues (wheat straw, olive husks, grape residues, and rice husks) and wood chips have been investigated on a bench scale. The experimental system establishes the conditions encountered by a thin (4 × 10-2 m diameter) packed bed of biomass particles suddenly exposed in a high-temperature environment, simulated by a radiant furnace. Product yields (gases, liquids, and char) and gas composition, measured for surface bed temperatures in the range 650−1000 K, reproduce trends already observed for wood. However, differences are quantitatively large. Pyrolysis of agricultural residues is always associated with much higher solid yields (up to a factor of 2) and lower liquid yields. Differences are lower for the total gas, and approximate relationships exist among the ratios of the main gas species yields, indicating comparable activation energies for the corresponding apparent kinetics of formation. However, while the ratios are about the same for wood chips, rice h...

Antitumor Activity of Sequential Treatment with Topotecan and Anti-Epidermal Growth Factor Receptor Monoclonal Antibody C225

Abstract: Epidermal growth factor (EGF)-related proteins such as transforming growth factor α (TGF-α) control cancer cell growth through autocrine and paracrine pathways. Overexpression of TGF-α and/or its receptor (EGFR) has been associated with a more aggressive disease and a poor prognosis. The blockade of EGFR activation has been proposed as a target for anticancer therapy. Monoclonal antibody (MAb) C225 is an anti-EGFR humanized chimeric mouse MAb that is presently in Phase II clinical trials in cancer patients. Previous studies have suggested the potentiation of the antitumor activity of certain cytotoxic drugs, such as cisplatin and doxorubicin, in human cancer cell lines by treatment with anti-EGFR antibodies. We have evaluated in human ovarian, breast, and colon cancer cell lines, which express functional EGFR, the antiproliferative activity of MAb C225 in combination with topotecan, a cytotoxic drug that specifically inhibits topoisomerase I and that has shown antitumor activity in these malignancies. A dose-dependent supraadditive increase of growth inhibition in vitro was observed when cancer cells were treated with topotecan and MAb C225 in a sequential schedule. In this respect, the cooperativity quotient, defined as the ratio between the actual growth inhibition obtained by treatment with topotecan followed by MAb C225 and the sum of the growth inhibition achieved by each agent, ranged from 1.2 to 3, depending on drug concentration and cancer cell line. Treatment with MAb C225 also markedly enhanced apoptotic cell death induced by topotecan. For example, in GEO colon cancer cells, 5 nm topotecan, followed by 0.5 μg/ml MAb C225, induced apoptosis in 45% cells as compared with untreated cells (6%) or to 5 nm topotecan-treated cells (22%). Treatment of mice bearing established human GEO colon cancer xenografts with topotecan or with MAb C225 determined a transient inhibition of tumor growth because GEO tumors resumed the growth rate of untreated tumors at the end of the treatment period. In contrast, an almost complete tumor regression was observed in all mice treated with the two agents in combination. This determined a prolonged life span of the mice that was significantly different as compared with controls ( P P P

Increased cardiomyocyte apoptosis and changes in proapoptotic and antiapoptotic genes bax and bcl-2 during left ventricular adaptations to chronic pressure overload in the rat

Abstract: Background—Left ventricular hypertrophy (LVH) represents both an adaptive response to increased cardiac work load and a precursor state of heart failure. Recent evidence linked cardiac myocyte death by apoptosis with LVH and heart failure. It remained unclear, however, whether apoptosis participated in the transition from LVH to left ventricular dysfunction (LVD). Methods and Results—Cardiac myocyte apoptotic events and changes in apoptosis-specific genes were studied in a rat model of chronic pressure overload induced by transverse aortic constriction. The changes in left ventricular geometry and function were assessed by echocardiography. Transverse aortic constriction rats progressively developed “concentric” LVH and subsequently, LVD. A similar distribution of LVH and LVD was found 18 weeks after surgery. At this time point, we determined the occurrence of myocyte apoptosis by DNA laddering, in situ DNA TUNEL labeling, and light and electron microscopy. The monitoring of proapoptotic and antiapoptotic...

Quality of life determinants and hearing function in an elderly population: Osservatorio Geriatrico Campano Study Group.

Abstract: Background: Hearing impairment (HI) is a very common condition in elderly people and the epidemiology together with hearing-related problems is still poorly investigated. Moreover,

The Tricept robot: Inverse kinematics, manipulability analysis and closed-loop direct kinematics algorithm

Abstract: This paper is aimed at presenting a study on the kinematics of the Tricept robot, which comprises a three-degree-of-freedom (dof) parallel structure having a radial link of variable length. The robot workspace is characterized and the inverse kinematics equation is obtained by using spherical coordinates. The inverse differential kinematics and statics are derived in terms of both an analytical and a geometric Jacobian, and a manipulability analysis along the various workspace directions is developed using the concept of force and velocity ellipsoids. A Jacobian-based Closed-Loop Direct Kinematics (CLDK) algorithm is presented to solve the direct kinematics problem along a given trajectory. Simulation results are illustrated for an industrial robot of the Tricept family.

A survey of robot interaction control schemes with experimental comparison

Abstract: A great many control schemes for a robot manipulator interacting with the environment have been developed in the literature. This paper is aimed at presenting a survey of robot interaction control schemes for a manipulator, the end effector of which comes in contact with a compliant surface. A salient feature of the work is the implementation of the schemes on an industrial robot with open control architecture equipped with a wrist force sensor. Two classes of control strategies are considered, namely, those based on static model-based compensation and those based on dynamic model-based compensation. The former provide a good steady-state behavior, while the latter enhance the behavior during the transient. The performance of the various schemes is compared in the light of disturbance rejection, and a thorough analysis is developed by means of a number of case studies.

Tryptase-Chymase Double-Positive Human Mast Cells Express the Eotaxin Receptor CCR3 and Are Attracted by CCR3-Binding Chemokines

Abstract: Eosinophils, basophils, and Th2 cells express the chemokine receptor CCR3, which binds eotaxin, RANTES, and some other chemokines. Using immunohistochemistry and flow cytometry, we demonstrate that CCR3 is also expressed by a variable proportion of human mast cells in gut, skin, and lung tissue. By contrast, with the same anti-CCR3 antibody (B711), CCR3 was poorly if at all detectable on human Th2 cells in vitro and in vivo. Eotaxin neither induced histamine release from purified human mast cells nor increased anti-IgE-stimulated histamine secretion. However, both eotaxin and RANTES elicited mast cell migration in vitro with a similar efficacy. High percentages of CCR3-expressing mast cells were present in the skin and in the intestinal submucosa; much lower percentages were found in the intestinal mucosa and in lung interstitium. Double immunostaining with anti-CCR3 and anti-chymase antibody showed that the vast majority of CCR3-expressing mast cells in the various tissues examined were tryptase-chymase double-positive. Therefore, tryptase-chymase double-positive mast cells express CCR3 and are attracted by CCR3-binding chemokines, eotaxin, and RANTES. Our findings indicate that these chemokines may play an important role in the differentiation and/or migration of this mast cell subset in connective tissues, as well as in sites of allergic inflammation.

Bone loss is correlated to the severity of growth hormone deficiency in adult patients with hypopituitarism.

Abstract: Reduced bone mineral density (BMD) has been reported in patients with isolated GH deficiency (GHD) or with multiple pituitary hormone deficiencies (MPHD). To investigate whether the severity of GHD was correlated with the degree of bone mass and turnover impairment, we evaluated BMD at the lumbar spine and femoral neck; circulating insulin-like growth factor I (IGF-I), IGF-binding protein-3 (IGFBP-3), and osteocalcin levels, and urinary cross-linked N-telopeptides of type I collagen (Ntx) levels in 101 adult hypopituitary patients and 35 sex- and age-matched healthy subjects. On the basis of the GH response to arginine plus GHRH (ARG+/-GHRH), patients were subdivided into 4 groups: group 1 included 41 patients with a GH peak below 3 microg/L (0.9 +/- 0.08 microg/L), defined as very severe GHD; group 2 included 25 patients with a GH peak between 3.1-9 microg/L (4.7 +/- 0.4 microg/L), defined as severe GHD; group 3 included 18 patients with a GH peak between 9.1-16.5 microg/L (11.0 +/- 0.3 microg/L), defined as partial GHD; and group 4 included 17 patients with a GH peak above 16.5 microg/L (28.3 +/- 4.3 microg/L), defined as non-GHD. In all 35 controls (group 5), the GH response after ARG+/-GHRH was above 16.5 microg/L (40.7 +/- 2.2 microg/L). In patients in group 1, circulating IGF-I (P < 0.001), IGFBP-3 (P < 0.05), osteocalcin (P < 0.001), and urinary Ntx levels (P < 0.001) were lower than those in group 3-5, which were not different from each other; the t score at the lumbar spine (-1.99 +/- 0.2) and that at the femoral neck (-1.86 +/- 0.3) were lower than those in groups 3 (-0.5 +/- 0.7, P < 0.01 and -0.3 +/- 0.7, P < 0.01, respectively), 4 (-0.5 +/- 0.2, P < 0.01 and -0.3 +/- 0.7, P < 0.01, respectively), and 5 (-0.5 +/- 0.2, P < 0.001 and 0.0 +/- 0.02, P < 0.001, respectively). In patients in group 2, circulating IGF-I and IGFBP-3 levels were not different from those in group 1, whereas the t scores at the lumbar spine (-1.22 +/- 0.3) and femoral neck (-0.9 +/- 0.3) were significantly higher and lower, respectively, than those in groups 1 and 5 (P < 0.05) but not those in groups 3 and 4, and serum osteocalcin and urinary Ntx levels were significant higher than those in group 1 and lower than those in groups 3-5 (P < 0.001). To evaluate the effect of isolated GHD vs. MPHD, patients were subdivided according to the number of their hormonal deficits, such as panhypopituitarism with (10 patients) or without (31 patients) diabetes insipidus, GHD with 1 or more additional pituitary deficit(s) (36 patients), isolated GHD (7 patients), 1-2 pituitary hormone deficit(s) without GHD (10 patients), and normal anterior pituitary function (7 patients). The t score at the lumbar spine and femoral neck and the biochemical parameters of bone turnover were not significantly different among the different subgroups with similar GH secretions. A significant correlation was found between the GH peak after ARG+GHRH and IGF-I, osteocalcin, urinary Ntx levels, and the t score at the lumbar spine, but not that at the femoral neck level. A significant correlation was also found between plasma IGF-I levels and the t score at the lumbar spine and femoral neck, serum osteocalcin, and urinary Ntx. Multiple correlation analysis revealed that the t score at the lumbar spine, but not that at the femoral neck, was more strongly predicted by plasma IGF-I levels (t = 3.376; P < 0.005) than by the GH peak after ARG+GHRH (t = -0.968; P = 0.338). In conclusion, a significant reduction of BMD associated with abnormalities of bone turnover parameters was found only in patients with very severe or severe GHD, whereas normal BMD values were found in non-GHD hypopituitary patients. These abnormalities were consistently present in all patients with GHD regardless of the presence of additional hormone deficits, suggesting that GHD plays a central role in the development of osteopenia in hypopituitary patients.

Six-DOF impedance control based on angle/axis representations

Abstract: A new approach to 6-DOF impedance control is proposed, where the end-effector orientation displacement is derived from the rotation matrix expressing the mutual orientation between the compliant frame and the desired frame. An alternative Euler angles-based description is proposed which mitigates the effects of representation singularities. Then, a class of angle/axis representations are considered to derive the dynamic equation for the rotational part of a 6-DOF impedance at the end effector, using an energy-based argument. The unit quaternion representation is selected to further analyze the properties of the rotational impedance. The resulting impedance controllers are designed according to an inverse dynamics strategy with contact force and moment measurements, where an inner loop acting on the end-effector position and orientation error is adopted to confer robustness to unmodeled dynamics and external disturbances. Experiments on an industrial robot were carried out, and the results of case studies are discussed.

Solid state 27Al NMR and FTIR study of lanthanum aluminosilicate glasses

Abstract: The structure of lanthanum aluminosilicate (LAS) glasses, containing: (15–25) mol% La2O3, (15–35) mol% Al2O3 and (40–70) mol% SiO2, were studied by 27Al nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FTIR). The effects of La2O3 and Al2O3 content on the properties and structure of the LAS glasses were evaluated. Al3+ ion enters into the glass structure mainly in fourfold co-ordination, forming ( AlO 4/2 ) − tetrahedra, and only in small amounts in fivefold and sixfold co-ordination. La3+ acts as network modifier, producing more non-bridging oxygen atoms as its content increases.

Brain Uncoupling Protein 2: Uncoupled Neuronal Mitochondria Predict Thermal Synapses in Homeostatic Centers

Abstract: Distinct brain peptidergic circuits govern peripheral energy homeostasis and related behavior. Here we report that mitochondrial uncoupling protein 2 (UCP2) is expressed discretely in neurons involved in homeostatic regulation. UCP2 protein was associated with the mitochondria of neurons, predominantly in axons and axon terminals. UCP2-producing neurons were found to be the targets of peripheral hormones, including leptin and gonadal steroids, and the presence of UCP2 protein in axonal processes predicted increased local brain mitochondrial uncoupling activity and heat production. In the hypothalamus, perikarya producing corticotropin-releasing factor, vasopressin, oxytocin, and neuropeptide Y also expressed UCP2. Furthermore, axon terminals containing UCP2 innervated diverse hypothalamic neuronal populations. These cells included those producing orexin, melanin-concentrating hormone, and luteinizing hormone-releasing hormone. When c-fos-expressing cells were analyzed in the basal brain after either fasting or cold exposure, it was found that all activated neurons received a robust UCP2 input on their perikarya and proximal dendrites. Thus, our data suggest the novel concept that heat produced by axonal UCP2 modulates neurotransmission in homeostatic centers, thereby coordinating the activity of those brain circuits that regulate daily energy balance and related autonomic and endocrine processes.

Leptin increases serotonin turnover by inhibition of brain nitric oxide synthesis

Abstract: Leptin administration inhibits diencephalic nitric oxide synthase (NOS) activity and increases brain serotonin (5-HT) metabolism in mice. We evaluated food intake, body-weight gain, diencephalic NOS activity, and diencephalic content of tryptophan (TRP), 5-HT, hydroxyindoleacetic acid (5-HIAA), and 5-HIAA/5-HT ratio after intracerebroventricular (ICV) or intraperitoneal (IP) leptin injection in mice. Five consecutive days of ICV or IP leptin injections induced a significant reduction in neuronal NOS (nNOS) activity, and caused a dose-dependent increase of 5-HT, 5-HIAA, and the 5-HIAA/5-HT ratio. Diencephalic 5-HT metabolism showed a significant increase in 5-HT, 5-HIAA, and the 5-HIAA/5-HT ratio 3 hours after a single leptin injection. This effect was maintained for 3 hours and had disappeared by 12 hours after injection. After a single IP leptin injection, the peak for 5-HT, 5-HIAA, and the 5-HIAA/5-HT ratio was achieved at 6 hours. Single injections of ICV or IP leptin significantly increased diencephalic 5-HT content. Leptin-induced 5-HT increase was antagonized by the coadministration of L-arginine only when the latter was ICV injected, whereas D-arginine did not influence leptin effects on brain 5-HT content. Finally, in nNOS-knockout mice, the appetite-suppressant activity of leptin was strongly reduced, and the leptin-induced increase in brain 5-HT metabolism was completely abolished. Our results indicate that the L-arginine/NO pathway is involved in mediating leptin effects on feeding behavior, and demonstrate that nNOS activity is required for the effects of leptin on brain 5-HT turnover.

Imaging of adrenal tumors using FDG PET: comparison of benign and malignant lesions.

Abstract: OBJECTIVE: The aim of this study was to differentiate benign from malignant adrenal tumors using positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) in patients with unilateral adrenal masses originally detected by CT or MR imaging. CONCLUSION: PET imaging with FDG can metabolically characterize adrenal masses. Abnormally increased FDG uptake in adrenal malignancies allows one to differentiate these abnormalities from benign lesions. Whole-body PET can also reveal extraadrenal tumor sites in patients with malignant tumors, using a single imaging technique for accurate disease staging.

Pro12Ala substitution in the peroxisome proliferator-activated receptor-gamma2 is not associated with type 2 diabetes.

Abstract: Peroxisome proliferator-activated receptor (PPAR)-gamma is a major regulator of adipogenesis and insulin sensitivity. The PPAR-gamma gene generates two isoforms through alternative splicing, PPAR-gamma1 and -gamma2, the latter having an additional stretch of 28 amino acids at its NH2-terminus in the ligand-independent activation domain. This extension renders PPAR-gamma2 more sensitive to insulin action. Since there is a Pro12Ala substitution in this domain, we tested whether it is related to type 2 diabetes or insulin resistance. Therefore, 131 type 2 diabetic patients and 312 normoglycemic control subjects were screened for the presence of the mutation and for major clinical and metabolic features. The frequency of the mutation did not differ significantly between diabetic patients and control subjects. BMI, insulin, and other metabolic and anthropometric variables were also not associated with the mutation. Although the study was carried out on a sufficiently large sample, the conclusions do not support a major role for the Pro12Ala substitution of the PPAR-gamma gene in the etiology of type 2 diabetes.

Expression of two major chitinase genes of Trichoderma atroviride (T. harzianum P1) is triggered by different regulatory signals.

Abstract: Regulation of the expression of the two major chitinase genes, ech42 (encoding the CHIT42 endochitinase) and nag1 (encoding the CHIT73 N-acetyl-β-d-glucosaminidase), of the chitinolytic system of the mycoparasitic biocontrol fungus Trichoderma atroviride (= Trichoderma harzianum P1) was investigated by using a reporter system based on the Aspergillus niger glucose oxidase. Strains harboring fusions of the ech42 or nag1 5′ upstream noncoding sequences with the A. niger goxA gene displayed a glucose oxidase activity pattern that was consistent under various conditions with expression of the native ech42 and nag1 genes, as assayed by Northern analysis. The expression product of goxA in the mutants was completely secreted into the medium, detectable on Western blots, and quantifiable by enzyme-linked immunosorbent assay. nag1 gene expression was triggered during growth on fungal (Botrytis cinerea) cell walls and on the chitin degradation product N-acetylglucosamine. N-Acetylglucosamine, di-N-acetylchitobiose, or tri-N-acetylchitotriose also induced nag1 gene expression when added to mycelia pregrown on different carbon sources. ech42 expression was also observed during growth on fungal cell walls but, in contrast, was not triggered by addition of chitooligomers to pregrown mycelia. Significant ech42 expression was observed after prolonged carbon starvation, independent of the use of glucose or glycerol as a carbon source, suggesting that relief of carbon catabolite repression was not involved in induction during starvation. In addition, ech42 gene transcription was triggered by physiological stress, such as low temperature, high osmotic pressure, or the addition of ethanol. Four copies of a putative stress response element (CCCCT) were found in the ech42 promoter.

PED/PEA-15: an anti-apoptotic molecule that regulates FAS/TNFR1-induced apoptosis.

Abstract: PED/PEA-15 is a recently cloned 15 kDa protein possessing a death effector domain (DED). In MCF-7 and HeLa cells, a fivefold overexpression of PED/PEA-15 blocked FasL and TNFα apoptotic effects. This effect of PED overexpression was blocked by inhibition of PKC activity. In MCF-7 and HeLa cell lysates, PED/PEA-15 co-precipitated with both FADD and FLICE. PED/PEA-15-FLICE association was inhibited by overexpression of the wild-type but not of a DED-deletion mutant of FADD. Simultaneous overexpression of PED/PEA-15 with FADD and FLICE inhibited FADD-FLICE co-precipitation by threefold. Based on cleavage of the FLICE substrate PARP, this inhibitory effect was paralleled by a threefold decline in FLICE activation in response to TNF-α. TNFα, in turn, reduces PED association with the endogenous FADD and FLICE of the cells. Thus, PED/PEA-15 is an endogenous protein inhibiting FAS and TNFR1-mediated apoptosis. At least in part, this function may involve displacement of FADD-FLICE binding through the death effector domain of PED/PEA-15.

Countercurrent fixed-bed gasification of biomass at laboratory scale

Abstract: A laboratory-scale countercurrent fixed-bed gasification plant has been designed and constructed to produce data for process modeling and to compare the gasification characteristics of several biomasses (beechwood, nutshells, olive husks, and grape residues). The composition of producer gas and spatial temperature profiles have been measured for biomass gasification at different air flow rates. The gas-heating value always attains a maximum as a function of this operating variable, associated with a decrease of the air-to-fuel ratio. Optimal gasification conditions of wood and agricultural residues give rise to comparable gas-heating values, comprised in the range 5−5.5 MJ/Nm3 with 28−30% CO, 5−7% CO2, 6−8% H2, 1−2% CH4, and small amounts of C2− hydrocarbons (apart from nitrogen). However, gasification of agricultural residues is more difficult because of bed transport, partial ash sintering, nonuniform flow distribution, and the presence of a muddy phase in the effluents, so that proper pretreatments are...