Showing papers by "University of Udine published in 1998"

A new prognostic score for survival of patients with chronic myeloid leukemia treated with interferon alfa. Writing Committee for the Collaborative CML Prognostic Factors Project Group.

Abstract: BACKGROUND: Interferon alfa is a conservative and widely used alternative to bone marrow transplantation in treatment of patients with early chronic myeloid leukemia (CML). A meta-analysis was conducted to develop a reliable prognostic scoring system for estimation of survival of patients with CML treated with interferon alfa. METHODS: Patients treated in prospective studies, including major randomized trials, were separated into learning and validation samples. Cox regression analysis and the minimum P-value approach were used to identify prognostic factors for patient survival and to discover groups in the learning sample with the greatest differences in survival. These findings were then validated by applying the new scoring system to patients in the validation sample. RESULTS: We collected data on 1573 patients who were participants in 14 studies involving 12 institutions; 1303 patients (learning sample, n = 981; validation sample, n = 322) were eligible for inclusion in this analysis, and their median survival time was 69 months (range, 1-117 months). Because two previously described prognostic scoring systems failed to discriminate risk groups satisfactorily, we developed a new scoring system that utilizes the following covariates: age, spleen size, blast count, platelet count, eosinophil count, and basophil count. Among 908 patients with complete data in the learning sample, three distinct risk groups were identified (median survival times of 98 months [n = 369; 40.6%], 65 months [n = 406; 44.7%], or 42 months [n = 133;14.6%]; two-sided logrank test, P< or =.0001). The ability of the new scoring system to discriminate these risk groups was confirmed by analysis of 285 patients with complete data in the validation sample (two-sided logrank test, P = .0002). CONCLUSIONS: A new prognostic scoring system for estimating survival of patients with CML treated with interferon alfa has been developed and validated through use of a large dataset.

Comparative analysis of genetic similarity among maize inbred lines detected by RFLPs, RAPDs, SSRs, and AFLPs

Abstract: DNA-based fingerprinting technologies have proven useful in genetic similarity studies. RFLP is still most commonly used in the estimation of genetic diversity in plant species, but the recently developed PCR-based marker techniques, RAPDs, SSRs and AFLPs, are playing an increasingly important role in these investigations. Using a set of 33 maize inbred lines we report on a comparison of techniques to evaluate their informativeness and applicability for the study of genetic diversity. The four assays differed in the amount of polymorphism detected. The information content, measured by the expected heterozygosity and the average number of alleles, was higher for SSRs, while the lowest level of polymorphism was obtained with AFLPs. However, AFLPs were the most efficient marker system because of their capacity to reveal several bands in a single amplification. In fact, the assay efficiency index was more than ten-fold higher for AFLPs compared to the other methods. Except for RAPDs, the genetic similarity trees were highly correlated. SSR and AFLP technologies can replace RFLP marker in genetic similarity studies because of their comparable accuracy in genotyping inbred lines selected by pedigree. Bootstrap analysis revealed that, in the set of lines analysed, the number of markers used was sufficient for a reliable estimation of genetic similarity and for a meaningful comparison of marker technologies.

Circulating Levels of Allopregnanolone in Humans: Gender, Age, and Endocrine Influences

Abstract: Allopregnanolone is a neuroactive steroid involved in modulating behavioral functions, stress, and neuroendocrine axes in rats. Changes in plasma allopregnanolone levels throughout the menstrual cycle have been reported in healthy women, but there exists no information on the possible gender or age-related changes or on the source(s) of circulating allopregnanolone. The aim of the present study was to assess serum allopregnanolone concentrations according to gender, menstrual cycle, age, and menopause in normal men and women; serum progesterone (P) and dehydroepiandrosterone (DHEA) levels were evaluated in the same specimens. In addition, the possible source of circulating allopregnanolone in fertile women was investigated by using stimulatory and inhibitory endocrine tests acting on the ovary and/or adrenal cortex. The present study included 189 fertile women, 112 postmenopausal women, and 46 men. Serum steroid levels were determined after extraction, using specific RIAs. Allopregnanolone levels in fertile women in the follicular phase were similar to those in age-matched men; no significant difference was found between fertile women in the follicular phase and postmenopausal women. The highest levels were found in fertile women during the luteal phase (P < 0.01). An age-related decrease was observed in men (P < 0.01), but not in women. P and DHEA levels were significantly higher in women than in men and were higher in fertile women than in postmenopausal women (P < 0.01). Both P and DHEA showed an age-related decrease in men and women (P < 0.01). Serum allopregnanolone and P, but not DHEA, significantly increased in response to a GnRH test, whereas corticotropin-releasing factor and ACTH tests elicited a significant increase in allopregnanolone, P, and DHEA levels (P < 0.01). The suppression of adrenal steroidogenesis by dexamethasone markedly reduced both allopregnanolone and DHEA serum levels (P < 0.01). In conclusion, the present study demonstrated that although men show an age-related decrease, serum allopregnanolone levels in women do not change with age and correlate with P levels during the menstrual cycle and in response to endocrine tests. Ovary and adrenal cortex may be major sources of circulating allopregnanolone in fertile women.

Antioxidant Properties of Tea Extracts as Affected by Processing

Abstract: The changes in the antioxidant properties of green and black tea extracts as a consequence of processing and storage conditions were evaluated through measurements of chain-breaking activity, oxygen scavenging capacity and redox potential. Pasteurisation and storage as well as forced oxygenation in both tea extracts caused an increase in the optical density and a decrease in the reducing power of the beverages; both were accompanied by unexpected increases in the chain-breaking activity of the beverages. Simple model systems containing catechin at a concentration similar to that found in the tea extracts were also considered to simulate the effects of enzymatic browning in tea. Possible explanations for the chain-breaking activity gain observed in the tea extracts as a consequence of processing were proposed.

Temporal and intensity coding of pain in human cortex.

Abstract: Porro, Carlo A., Valentina Cettolo, Maria Pia Francescato, and Patrizia Baraldi. Temporal and intensity coding of pain in human cortex. J. Neurophysiol. 80:3312–3320, 1998. We used a high-resolutio...

The consensus glossary of temporal database concepts — February 1998 version

Abstract: This document1 contains definitions of a wide range of concepts specific to and widely used within temporal databases. In addition to providing definitions, the document also includes explanations of concepts as well as discussions of the adopted names.

Meal-generated oxidative stress in type 2 diabetic patients

Abstract: OBJECTIVE Free radical production has been reported to be increased in diabetic patients and to be involved in the pathogenesis of diabetic complications. In this study, a standardized meal was administered to 10 type 2 diabetic patients and 10 healthy matched normal subjects to evaluate its effects on plasma oxidative stress generation. RESEARCH DESIGN AND METHODS In diabetic patients, at baseline and after the meal, plasma malondialdehyde (MDA), vitamin C, protein SH groups, uric acid, vitamin E, and total plasma radical-trapping parameter, which evaluates plasma antioxidant capacity due to known and unknown antioxidants present in the plasma as well as their mutual cooperation, were measured. RESULTS After the meal, plasma MDA and vitamin C increased, while protein SH groups, uric acid, vitamin E, and total plasma radical-trapping parameter decreased more significantly in the diabetic subjects than in control subjects. CONCLUSIONS This finding shows that in the absorptive phase, free radicals are produced in diabetic patients. Since plasma glucose, but not insulin, rose significantly more in diabetic subjects than in control subjects, hyperglycemia may play an important role in the generation of postprandial oxidative stress in diabetic patients.

Antioxidant defences are reduced during the oral glucose tolerance test in normal and non-insulin-dependent diabetic subjects

Abstract: Background Free radical production has been reported to be increased in patients with diabetes mellitus, and it has been suggested that hyperglycaemia may directly contribute to the generation of oxidative stress. The aim of the present study was to evaluate the effects of an acute increase in glycaemia on plasma antioxidant defences. Results During the oral glucose tolerance test (OGTT), plasma concentration of protein-bound sulphydryl (SH) groups, vitamin C, vitamin E and uric acid significantly decreased in normal as well as non-insulin-dependent diabetes mellitus (NIDDM) subjects. Total plasma radical-trapping activity, which evaluates plasma antioxidant capacity due to known and unknown antioxidants present in the plasma as well as their mutual co-operation, was also significantly reduced. Conclusion This finding supports the hypothesis that hyperglycaemia may, even acutely, induce an oxidative stress.

Complementary right and left hemifield use for predatory and agonistic behaviour in toads.

Abstract: Cerebral lateralization, the differing specializations of the right and left sides of the brain once thought to be unique of humans, is now well known to occur in both birds and mammals. Here we report that in toads the right hemisfield of vision guides predatory tongue-striking responses towards moving prey and the left hemisfield guides agnostic tongue-striking responses towards conspecifics. This indicates, for the first time, complementary cerebral specializations for visual processing in anurans, and strongly supports the hypothesis that lateralized brain functions in birds and mammals may have arisen from a common lateralized ancestor. Complementary specializations in visual processing may have originally evolved to avoid problem of response competition during control of medial organs such as the tongue in organisms with laterally placed eyes and, in organisms with wider binocular overlap, it appears to be retained for initial detection of stimuli in the extreme lateral fields.

Free Air CO2 Enrichment of potato (Solanum tuberosum L.): development, growth and yield

Abstract: A FACE (Free Air CO2 Enrichment) experiment was carried out on Potato (Solanum tuberosum L., cv. Primura) in 1995 in Italy. Three FACE rings were used to fumigate circular field plots of 8 m diameter while two rings were used as controls at ambient CO2 concentrations. Four CO2 exposure levels were used in the rings (ambient, 460, 560 and 660 μmol mol–1). Phenology and crop development, canopy surface temperature, above- and below-ground biomass were monitored during the growing season. Crop phenology was affected by elevated CO2, as the date of flowering was progressively anticipated in the 660, 560, 460 μmol mol–1 treatments. Crop development was not affected significantly as plant height, leaf area and the number of leaves per plant were the same in the four treatments. Elevated atmospheric CO2 levels had, instead, a significant effect on the accumulation of total nonstructural carbohydrates (TNC = soluble sugars + starch) in the leaves during a sunny day. Specific leaf area was decreased under elevated CO2 with a response that paralleled that of TNC concentrations. This reflected the occurrence of a progressive increase of photosynthetic rates and carbon assimilation in plants exposed to increasingly higher levels of atmospheric CO2. Tuber growth and final tuber yield were also stimulated by rising CO2 levels. When calculated by regression of tuber yield vs. the imposed levels of CO2concentration, yield stimulation was as large as 10% every 100 μmol mol–1 increase, which translated into over 40% enhancement in yield under 660 μmol mol–1. This was related to a higher number of tubers rather than greater mean tuber mass or size. Leaf senescence was accelerated under elevated CO2 and a linear relationship was found between atmospheric CO2 levels and leaf reflectance measured at 0.55 μm wavelength. We conclude that significant CO2 stimulation of yield has to be expected for potato under future climate scenarios, and that crop phenology will be affected as well.

A review of neuroendocrine neoplasms of the larynx: update on diagnosis and treatment

Abstract: Neuroendocrine neoplasms of the larynx have been divided into those of epithelial or neural origin. The latter consist of paragangliomas while the epithelial origin group can be divided into the typical and atypical carcinoids and small cell neuroendocrine carcinomata, the latter consisting of the oat cell type, the intermediate cell type and the combined cell type. There are now over 500 cases of neuroendocrine neoplasms of the larynx in the literature. The diagnosis is primarily based on light microscopy, and, in some instances, it may be supported by special histochemical studies. It should be confirmed by immunocytochemical and/or ultrastructural investigation. The different biological behaviour of neuroendocrine neoplasms of the larynx makes a specific diagnosis of paramount importance, since treatment depends on diagnostic accuracy. Typical carcinoid is an extremely rare lesion. It is treated preferably by conservative surgery; elective neck dissection is not necessary because of the lack of lymph node metastases at diagnosis. Chemotherapy and/or radiotherapy have not been effective in the limited number of patients treated thus far. Prognosis is excellent with cure following surgery. Atypical carcinoid is the most frequent non-squamous carcinoma of the larynx. The mainstay of treatment is surgery. Elective neck dissection should be performed because of the high likelihood of cervical lymph node metastases. Primary radiation therapy with adjuvant chemotherapy is not indicated. The survival rate is 48 per cent at five years and 30 per cent at 10 years. Although the larynx is one of its most common extrapulmonary sites, small cell neuroendocrine carcinoma is still a rare tumour. Surgical results for this tumour have been disappointing and is reserved for cases of local relapse with no evidence of metastasis. Chemotherapy and radiotherapy currently appear to offer the least disabling and most effective forms of therapy. The two- and five-year survival rates are 16 per cent and five per cent, respectively. Paraneoplastic syndromes have occasionally been reported in association with carcinoid tumours (typical and atypical) and small cell neuroendocrine carcinoma. There have been also rare reports of an elevated neuropeptide serum level. Paraganglioma is the only laryngeal neuroendocrine neoplasm with a female preponderance (3:1). Confusion with atypical carcinoid has led to incorrect diagnosis and inappropriate classification schemes, erroneously suggesting that laryngeal paraganglioma has the potential for aggressive behaviour. Conservative surgery represents the treatment of choice; elective neck dissection is not necessary, and the prognosis is excellent.

Hyperglycemia-induced circulating ICAM-1 increase in diabetes mellitus: the possible role of oxidative stress.

Abstract: ICAM-1 is one of the most important intercellular adhesion molecules involved in atherogenesis. Previous studies reported increased circulating ICAM-1 plasma levels in NIDDM patients with or without vascular complications. It has been suggested that an acute increase of plasma glucose may produce an oxidative stress in man, and in vitro studies have demonstrated that high glucose and free radicals induce cellular expression of ICAM-1. In this study, three different experiments were performed in nine NIDDM patients and in seven matched healthy controls: oral glucose tolerance test, antioxidant glutathione i.v. administration for two h, oral glucose tolerance test plus glutathione i.v. administration. Blood samples were drawn at -15 min and every 30 min from 0 to 180 min. During the oral glucose tolerance test, circulating ICAM-1 plasma levels significantly increased in both diabetic and normal subjects. Glutathione administration during the oral glucose tolerance test abolished this phenomenon. Glutathione administered alone significantly decreased circulating ICAM-1 plasma levels in diabetic patients, while no effect was observed in the normal subjects. These data suggest that hyperglycemia may induce an increase of circulating ICAM-1 plasma levels through an oxidative stress, and that the antioxidant glutathione counterbalances this effect. These data support the hypothesis of a causal relationship linking hyperglycemia, oxidative stress and atherogenesis in diabetes mellitus.

The effect of water in the low-temperature catalytic oxidation of hydrogen sulfide to sulfur over activated carbon

Abstract: This study investigates the use of low-temperature catalytic oxidation for the removal of H 2 S from tail gases originating from geothermal plants, with special focus on the effect of water on the overall performance of the activated carbon catalyst. It is shown that water strongly influences the reaction rate and the total amount of sulfur that can be adsorbed on the catalyst prior to regeneration. It is suggested that the reaction takes place in a thin water layer, inside the carbon pores, from the reaction of dissolved H 2 S with chemisorbed oxygen.

Transmission of European stone fruit yellows phytoplasma by Cacopsylla pruni.

Abstract: Experimental transmission of European stone fruit yellows phytoplasma to Japanese plum cv. ‘Ozark Premier’ was achieved using Cacopsylla pruni, caught in the field or raised on infected plants under controlled conditions. Using different groups of infectious psyllas, 89% of the inoculated test plants were infected. Both nymphs and adults were able to transmit. Insects exposed to test plants immediately after capture or raised in cages transmitted the disease. After an incubation period of 4-5 months the first test plants showed typical symptoms. Sources of inoculum, test plants and vectors were examined by PCR for the presence of phytoplasmas. Following digestion of the amplification products with restriction enzymes, isolates from plants and insects showed the same restriction profiles. Interestingly, pear decline and European stone fruit yellows, members of the apple proliferation cluster, are both transmitted by Cacopsylla spp.

Expression and secretion of inhibin and activin in normal and neoplastic uterine tissues. High levels of serum activin A in women with endometrial and cervical carcinoma

Abstract: Inhibins and activins are growth factors belonging to the transforming growth factor-beta) family and are known to influence cell proliferation and differentiation. Because transforming growth factor-beta is involved in physiological and tumoral changes of uterine tissues, the present study aimed to evaluate whether human normal and neoplastic endometrial and cervical epithelial cells express and secrete inhibin A, inhibin B, and activin A. To test this hypothesis, different approaches were used. By RT-PCR, the expression of specific messenger RNAs (mRNAs) for the inhibin alpha, activin betaA and betaB subunits, and activin receptor type II and type IIB was investigated: 1) in primary cultures of endometrial (stroma and epithelium) or cervical (epithelium) cells from healthy women; and 2) in specimens of endometrial or cervical carcinoma. To demonstrate a possible secretion of the proteins, dimeric inhibin A, inhibin B, and activin A were measured in culture medium of normal epithelial or stromal endometrial cells and in uterine washing fluid of healthy women or patients with endometrial adenocarcinoma. Levels of the proteins were also measured in serum of women with endometrial or cervical carcinoma. Cultured endometrial stromal or epithelial cells and epithelial cervical cells expressed inhibin alpha, activin betaA and betaB, and activin receptor type II and type IIB mRNAs. The same finding was obtained in specimens of endometrial or cervical carcinomas. Dimeric inhibin A, inhibin B, and activin A were measured in culture medium of both endometrial and cervical cells. In particular, resulting activin A levels were significantly higher in epithelial than in stromal cultured endometrial cells (P < 0.01). Dimeric proteins were also detected in the washing fluid of the uterine cavities of healthy women (controls) and with endometrial adenocarcinoma, in which higher activin A levels were found (P < 0.01 vs. controls). Women with endometrial carcinoma showed serum activin A levels significantly higher than healthy controls (P < 0.01), which significantly decreased after surgical removal of endometrial or cervical tumors (P < 0.01). The present study, for the first time, showed that inhibin A, inhibin B, and activin A, as well as activin receptors, are expressed in normal and neoplastic human uterine tissues. A secretion of activin A from tumoral cells into systemic circulation is suggested by the observation that the high levels in serum of patients with endometrial or cervical carcinoma decreased after the surgical removal of the tumor.

Inhibin B is the major form of inhibin/activin family secreted by granulosa cell tumors

Abstract: Both experimental and clinical studies suggest that inhibin plays a critical role in the development of granulosa cell tumors (GCT), a subgroup of malignant ovarian tumors Inhibin has been proposed as a biological marker for the follow-up of patients bearing these particular tumors Hitherto, there is no general agreement on the molecular form(s) of the inhibin family that are secreted by malignant granulosa cells Using specific and sensitive immunoassays for activin A and for inhibins A and B, we investigated the production of these molecules in patients with either an adult GCT (n = 13) or an epithelial ovarian cancer (n = 11) Results showed that serum activin A level was increased in all patients, independently of their clinical status (progressive disease or remission) in comparison to that observed in the healthy pre- and postmenopausal women Most of the patients also presented a moderate increase in serum inhibin A level compared to that in controls Only one of eight patients with a progressive

Microsatellite DNA in Actinidia chinensis: isolation, characterisation, and homology in related species

Abstract: We have isolated and sequenced 263 microsatellite-containing clones from two small insert libraries of Actinidia chinensis enriched for (AC/GT) and (AG/CT) repeats, respectively. Primer pairs were designed for 203 microsatellite loci and successfully amplified from both plasmid and A. chinensis genomic DNA. In this paper we report the sequences of 40 primer pairs for which we have demonstrated Mendelian segregation in the progeny from controlled crosses. The polymorphism of ten microsatellites of each type was evaluated in four diploid and six tetraploid genotypes of A. chinensis. All microsatellites proved to be polymorphic, the number of alleles per locus detected in polyacrylamide sequencing gels ranging from 9 to 17. The high degree of polymorphism in Actinidia renders these markers useful either for mapping in A. chinensis or for fingerprinting cultivars of both domesticated kiwifruit species (A. chinensis and A. deliciosa). While most primer pairs produced single amplification products, about 20% generated banding patterns consistent with the amplification of two different loci. This supports the hypothesis that diploid species of Actinidia (2n=2x=58) are polyploid in origin with a basic chromosome number x=14/15 and that chromosome duplication may have occurred during the evolution of the genus. Finally, we have assayed the cross-species transportability of primer pairs designed from A. chinensis sequences and have found extensive cross-species amplification within the genus Actinidia; 75% of primer pairs gave successful amplification in the eight species assayed (A. arguta, A. rufa, A. polygama, A. chrysantha, A. callosa, A. hemsleyana, A. eriantha, and A. deliciosa), which are representative of the four sections into which the genus is currently split.