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A Ranieri

Publications and source records attributed to A Ranieri.

At least 19 recordsLinked to original sources
PubMed2006

Measuring, modelling and testing ozone exposure, flux and effects on vegetation in southern European conditions--what does not work? A review from Italy.

Ozone (O3) exposure at Italian background sites exceeds UN/ECE concentration-based critical levels (CLe(c)), if expressed in terms of AOT40. Yet the occurrence of adverse effects of O3 on forests and crops is controversial. Possible reasons include (i) ability of response indicators to provide an unbiased estimate of O3 effects, (ii) setting of current CLe(c) in terms of cut-off value and accumulation level, (iii) response functions adopted to infer a critical level, (iv) environmental limitation to O3 uptake and (v) inherent characteristics of Mediterranean vegetation. In particular, the two latter points suggest that critical levels based on accumulated stomatal flux (CLe(f)) can be a better predictor of O3 risk than CLe(c). While this concept is largely acknowledged, a number of factors may limit its applicability for routine monitoring. This paper reviews levels, uptake and vegetation response to O3 in Italy over recent years to discuss value, uncertainty and feasibility of different approaches to risk assessment.

Crops, Agricultural↗
PubMed2006

Hypnic headache: an update.

Hypnic headache (HH) is a rare sleep-associated primary headache disorder, usually affecting aged people, first described by Raskin in 1988. The headache attacks, single or multiple in one night, occur exclusively during sleep and tend to present at a consistent time each night, sometimes during a dream. Compared to the original description, newly reported cases have expanded the clinical spectrum of the disorder to include unilateral forms (about 40%, half of which are side-locked), forms with a longer duration (up to 3 h) and cases with onset in juvenile/adult age. The male predominance found in Raskin's series has not been confirmed by subsequent observations. To date the reported F/M ratio is 1.7/1. Pain is of severe intensity in less then one-third of cases and mild-moderate in about two-thirds. The location of pain is fronto-temporal in over 40% of cases; headache is throbbing in 38% of cases, dull in 57% and stabbing in less than 5%. Nausea is reported in 19% of cases; photophobia, phonophobia or both are present in 6.8%. Mild autonomic signs (lacrimation, nasal congestion, ptosis) may rarely be present. In 2004, HH was included in Group 4 of the International Classification of Headache Disorders-II (Other primary headaches). Sufficient evidence, mainly from polysomnographic studies, indicates that HH is a primary rapid eye movement (REM) sleep-related headache disorder of chronobiological origin. Lithium, melatonin, indomethacin and caffeine at bedtime are among the most effective therapeutic options. The pathophysiology of HH is still unclear. Available data allow speculation that, in predisposed subjects, an age-related impairment of suprachiasmatic nucleus could cyclically activate a disnociceptive mechanism leading to both a sudden awakening and headache. The mechanism may be precipitated by neurophysiologic events such as the strong reduction of firing occurring in the dorsal raphe nucleus during a REM sleep phase.

Headache Disorders, Primary↗
PubMed2006

Outlook: who needs LH in ovarian stimulation?

LH plays a key role in the intermediate-late phases of folliculogenesis. Although ovarian stimulation is efficiently achieved in most cases by the administration of exogenous FSH alone, specific subgroups of women may benefit from LH activity supplementation during ovarian stimulation. Some authors have found improved outcome with LH activity supplementation in advanced reproductive age women. Experience suggests that in about 10-12% of young normogonadotrophic patients treated with a gonadotrophin-releasing hormone agonist (GnRH-a) long protocol plus recombinant FSH human (r-hFSH), a 'steady response' is observed. In this subgroup of women, a higher number of oocytes is retrieved when daily LH activity supplementation is given from stimulation day 8, if compared with the standard FSH dose increase. Another subgroup of patients who may benefit from LH activity supplementation are those at risk for poor ovarian response treated with GnRH antagonist. Recent data demonstrate that in these women, when GnRH is administered in a flexible protocol, the concomitant addition of recombinant human LH improves the number of mature oocytes retrieved, when compared with the standard GnRH-a flare-up protocol. Thus, well calibrated LH administration improves the ovarian outcome in patients >35 years, in those showing an initial abnormal ovarian response to r-hFSH monotherapy, and in 'low prognosis' women treated with GnRH antagonists.

Adult↗
PubMed2005

Axial ligation and polypeptide matrix effects on the reduction potential of heme proteins probed on their cyanide adducts.

The enthalpic and entropic changes accompanying the reduction reaction of the six-coordinate cyanide adducts of cytochrome c, microperoxidase-11 and a few plant peroxidases were measured electrochemically. Once the compensating changes in reduction enthalpy and entropy due to solvent reorganization effects are factorized out, it is found that cyanide binding stabilizes enthalpically the ferriheme following the order: cyochrome c > peroxidase > microperoxidase-11. The effect is inversely correlated to the solvent accessibility of the heme. Comparison of the reduction thermodynamics for the cyanide adducts of cytochrome c and plant peroxidases with those for microperoxidase-11 and myoglobin, respectively, yielded an estimate of the consequences of protein encapsulation and of the anionic character of the proximal histidine on the reduction potential of the heme-cyanide group. Insertion of the heme-CN group into the folded peptide chain of cyt c induces an enthalpy-based decrease in E degrees ' of approximately 100 mV, consistent with the lower net charge of the oxidized as compared to the reduced iron center, whereas a full imidazolate character of the proximal histidine stabilizes enthalpically the ferriheme by approximately 400 mV. The latter value should be best considered as an upper limit since it also includes some solvation effects arising from the nature of the protein systems being compared.

Cyanides↗
PubMed2005

A clinical comparison of trigeminal neuralgic pain in patients with and without underlying multiple sclerosis.

Despite clinical similitude, there is a tendency to consider trigeminal pain in multiple sclerosis (MS) as a distinct condition. To evaluate clinical differences in trigeminal pain presentation in patients with and without underlying MS, we compared clinical characteristics of facial pain found in 15 consecutive MS patients with those reported by 13 consecutive subjects diagnosed with classical trigeminal neuralgia. The only significant difference between MS and non-MS neuralgic patients was the age of onset of pain (43.4+/-10.5 in MS vs. 59.6+/-11.50 in non-MS patients, p=0.000629, unpaired Student's t-test). No differences were observed for side, duration and quality of pain, trigeminal branches involved, presence of trigger areas or factors, pain refractive period, remitting-relapsing or chronic course. There was only a trend without statistical significance in interval pain and trigeminal hypoesthesia, more frequent in MS population. Only one patient in the MS group presented with long-lasting episodes (45-60 min) of atypical odontalgia. Our findings support the view of a common pathogenetic mechanism underlying TN in the two groups, possibly related to demyelination of the trigeminal entry root in the pons. Typical TN in MS patients should be considered as "symptomatic trigeminal neuralgia".

Adult↗
PubMed2004

Recombinant human LH supplementation versus recombinant human FSH (rFSH) step-up protocol during controlled ovarian stimulation in normogonadotrophic women with initial inadequate ovarian response to rFSH. A multicentre, prospective, randomized controlled trial.

BACKGROUND: In approximately 12-14% of young normogonadotrophic women treated with a depot GnRH agonist long protocol, the initial ovarian response to recombinant human FSH (rFSH) can be suboptimal. We have tested the hypothesis that these women may benefit from recombinant human LH (rLH) supplementation in a multicentre, prospective, randomized trial compared with patients treated with an rFSH step-up protocol. METHODS: A total of 260 young normogonadotrophic women undergoing controlled ovarian stimulation with a GnRH agonist long protocol for IVF/ICSI were enrolled. The starting dose of rFSH was 225 IU. One hundred and thirty patients with serum estradiol levels <180 pg/ml and with at least six follicles with a mean diameter >5 mm but none >10 mm on both day 5 and day 8 of stimulation were randomly allocated to two groups. From the eighth day of stimulation, women in group A (n=65) received 150 IU of rLH in addition to rFSH, while those in group B (n=65) had an increase of 150 IU in the daily dose of rFSH (step-up protocol). One hundred and thirty normally responding women continued monotherapy with rFSH and served as a further control population (group C). RESULTS: The mean number of cumulus-oocyte complexes retrieved in group A (9.0+/-4.3) was significantly higher (P<0.01) compared with group B (rFSH 6.1+/-2.6) but significantly lower compared with group C (10.49+/-3.7, P<0.05). Implantation and pregnancy rates were significantly lower (P<0.05) in the rFSH step-up group (10.5 and 29.3% respectively) when compared with normal responders (18.1 and 47.3% respectively). CONCLUSIONS: rLH supplementation is more effective than increasing the dose of rFSH in terms of ovarian outcome in patients with an initial inadequate ovarian response to rFSH alone.

Adolescent↗
PubMed2004

Solvent-based deuterium isotope effects on the redox thermodynamics of cytochrome c.

The reduction thermodynamics of cytochrome c (cytc), determined electrochemically, are found to be sensitive to solvent H/D isotope effects. Reduction of cytochrome c is enthalpically more favored in D(2)O with respect to H(2)O, but is disfavored on entropic grounds. This is consistent with a reduction-induced strengthening of the H-bonding network within the hydration sphere of the protein. No significant changes in E degrees ' occur, since the above variations are compensative. As a main result, this work shows that the oxidation-state-dependent differences in protein solvation, including electrostatics and solvent reorganization effects, play an important role in determining the individual enthalpy and entropy changes of the reduction process. It is conceivable that this is a common thermodynamic feature of all electron transport metalloproteins. The isotope effects turn out to be sensitive to buffer anions which specifically bind to cytc. Evidence is gained that the solvation thermodynamics of both redox forms of cytc are sensibly affected by strongly hydrated anions.

Animals↗
PubMed2004

Effects of recombinant LH (rLH) supplementation during controlled ovarian hyperstimulation (COH) in normogonadotrophic women with an initial inadequate response to recombinant FSH (rFSH) after pituitary downregulation.

BACKGROUND: This study was aimed to evaluate the effect of different recombinant LH (rLH) doses on the ovarian outcome of normogonadotrophic women with an initial inadequate response to recombinant FSH (rFSH) after pituitary downregulation. METHODS: Only women undergoing a 'long protocol' with a GnRH-agonist followed by rFSH administration were enrolled. On the eighth day of stimulation, 46 patients with serum E2 levels < 180 pg/ml and with no follicle > 10 mm were randomized in two groups to receive a supplementation with a daily rLH dose of 75 (group A) or 150 IU (group B), respectively. Forty-six normal responders continuing their monotherapy with rFSH formed the control group (C). RESULTS: The mean number of oocytes retrieved and the percentage of mature oocytes in the group B (9.65 +/- 2.16, 79.0%) were comparable with those observed in the group C (10.65 +/- 2.8, 82.5%) and significantly higher when compared with the group A (6.39 +/- 1.53, 65.7%). The mean number of ampoules of rLH was significantly higher in the group B (14.4 +/- 2.0 vs. 9.65 +/- 1.1), whereas these patients received a significantly lower mean number of rFSH ampoules (44.6 +/- 7.4 vs. 36.1 +/- 3.8). Seven (30.4%), 9 (39.1%) and 22 (47.8%) pregnancies were achieved in the groups A, B and C, respectively. CONCLUSIONS: These results suggest that patients with initial inadequate responses to rFSH after pituitary downregulation benefit from the addition of a daily dose of 150 IU of rLH, starting from the eighth day of stimulation.

Adult↗
PubMed2003

Early production and scavenging of hydrogen peroxide in the apoplast of sunflower plants exposed to ozone.

The present work set out to define the processes involved in the early O3-induced H2O2 accumulation in sunflower plants exposed to a single pulse of 150 ppb of O3 for 4 h. Hydrogen peroxide accumulation only occurred in the apoplast and this temporally coincided with the fumigation period. The inhibitor experiments suggested that both the plasma membrane-bound NAD(P)H oxidase complex and cell-wall NAD(P)H PODs contributed to H2O2 generation. To investigate the mechanisms responsible for O3-induced H2O2 accumulation further, both production and scavenging of H2O2 were investigated in the extracellular matrix after subcellular fractionation. The results indicated that H2O2 accumulation is a complex and highly regulated event requiring the time-dependent stimulation and down-regulation of differently located enzymes, some of which are involved in H2O2 generation and degradation, not only during the fumigation period but also in the subsequent recovery period in non-polluted air. Owing to the possible interplay between H2O2 and ethylene, the time-course of ethylene emission was analysed too. Ethylene was rapidly emitted following O3 exposure, but it declined to control values as early as after 4 h of exposure. The early contemporaneous detection of increased ethylene and H2O2 levels after 30 min of exposure does not allow a clear temporal relationship between these two signalling molecules to be established.

Cell Membrane↗
PubMed2002

End-to-end urethroplasty: long-term results.

OBJECTIVE: To retrospectively review patients with strictures (<3 cm) of the bulbous urethra who had undergone urethroplasty with excision of the stenotic segment and end-to-end anastomosis. PATIENTS AND METHODS: The review included 74 patients (all men, mean age 39 years, range 18-70) treated between 1989 and 1999 for strictures 5-30 mm long. Forty-one of the patients (55%) had been treated previously, 39 endoscopically (urethrotomy and/or dilatation) and two surgically. Surgical access was perineal, with the patient in an exaggerated lithotomy position; the stenotic segment was excised and the stumps spatulated for end-to-end anastomosis. The mean (range) duration of surgery was 140 (75-280) min. There were no complications during or after surgery, and none related to the duration in the lithotomy position. RESULTS: At a mean follow-up of 60 months, 93% of the patients had no recurrence of the stricture and were therefore considered cured. There were no treatment-related complications. CONCLUSION: End-to-end anastomosis is confirmed as the treatment of choice for short bulbous urethral strictures, giving cure rates close to 100%.

Adult↗
PubMed2001

Effects of specific anion-protein binding on the alkaline transition of cytochrome c.

The thermodynamic parameters of the alkaline transition of beef heart ferricytochrome c have been measured through direct electrochemistry experiments carried out at variable pH and temperature in the presence of different sulfate concentrations. Sulfate is known to bind specifically to cytochrome c in a sequential manner at two surface sites. The effects of such a specific binding reflect on the thermodynamics of the transition and can be satisfactorily interpreted within the frame of the Debye-Hückel theory with simple electrostatic considerations. In particular, the increase in the thermodynamic pKa values (extrapolated to I = 0) upon sulfate binding turns out to be a fully enthalpic effect which can be accounted for by considering the coulombic effects of the formation of ionic couple(s) on the protein surface. This study also shows that the apparent pKa values at finite ionic strength are only moderately affected by the nature of the anion in solution, and differences tend to vanish at high ionic strength.

Animals↗
PubMed2001

Redox properties and acid-base equilibria of zucchini mavicyanin.

The reduction potential of mavicyanin isolated from zucchini peelings, which is a blue copper protein belonging to the subclass of the phytocyanins, has been determined through direct electrochemistry as a function of temperature and pH. The enthalpy and entropy changes accompanying protein reduction were found to be very similar with those determined previously for other phytocyanins and to differ remarkably from those of azurins and plastocyanins. This finding contributes to further characterize phytocyanins as a distinct cupredoxins family also on thermodynamic grounds and improves our understanding of how the reduction potential of these metal centers in proteins is modulated by coordinative and solvation properties. The E degrees' of mavicyanin is found to be sensitive to two acid-base equilibria at the extremes of pH. One occurs below pH 4, and is related to the protonation and detachment from the Cu(I) center of a histidine ligand. The other, observed above pH 8, causes a remarkable change in the electrostatic potential and/or the field strength around the copper.

Journal Article↗
PubMed2001

Rescue of IVF cycles by HMG in pituitary down-regulated normogonadotrophic young women characterized by a poor initial response to recombinant FSH.

BACKGROUND: The aim of this study was to investigate the effects of adding human menopausal gonadotrophin (HMG) during controlled ovarian stimulation in normoovulatory normogonadotrophic patients showing an initial suboptimal response to a standardized long protocol therapy with recombinant FSH (rFSH) (300 IU/day). METHODS: A total of 43 such patients were randomized in two groups. In Group A, 150 IU rFSH was substituted by 150 IU HMG after day 8 of stimulation. The stimulation protocol of Group B involved a simple increase of the daily rFSH dose to 375 IU after day 8. A total of 40 BMI and age matched patients with an optimal ovarian response formed the control group (Group C). RESULTS: The mean Group A serum concentration of oestradiol on the day of HCG administration and average number of oocytes retrieved were significantly higher than Group B (P < 0.001) and equivalent to Group C. A total of 10 pregnancies (50%) in Group A, 8 (34.8%) in Group B and 19 (47.5%) in the control group were achieved. CONCLUSIONS: The data suggest that LH supplementation improves the ovarian outcome in patients characterized by an inadequate initial response to rFSH therapy in a long protocol.

Adult↗
PubMed2001

Iron deficiency differently affects peroxidase isoforms in sunflower.

The response of both specific (ascorbate peroxidase, APX) and unspecific (POD) peroxidases and H(2)O(2) content of sunflower plants (Helianthus annuus L. cv. Hor) grown hydroponically with (C) or without (-Fe) iron in the nutrient solution were analysed to verify whether iron deficiency led to cell oxidative status. In -Fe leaves a significant increase of H(2)O(2) content was detected, a result confirmed by electron microscopy analysis. As regards extracellular peroxidases, while APX activity significantly decreased, no change was observed in either soluble guaiacol or syringaldazine-dependent POD activity following iron starvation. Moreover, guaiacol-dependent POD activity was found to decrease in both ionically and covalently-cell-wall bound fractions, while syringaldazine-POD activity decreased only in the covalently-bound fraction. At the intracellular level both guaiacol-POD and APX activities underwent a significant decrease. The overall reduction of peroxidase activity was confirmed by the electrophoretic separation of POD isoforms and, at the extracellular level, by cytochemical localization of peroxidases by diaminobenzidine staining. The electrophoretic separation, besides quantitative differences, also revealed quantitative changes, particularly evident for ionically and covalently-bound fractions. Therefore, in sunflower plants, iron deficiency seems to affect the different peroxidase isoenzymes to different extents and to induce a secondary oxidative stress, as indicated by the increased levels of H(2)O(2). However, owing to the almost completely lack of catalytic iron capable of triggering the Fenton reaction, iron-deficient sunflower plants are probably still sufficiently protected against oxidative stress.

Ascorbate Peroxidases↗
PubMed2000

Redox state and peroxidase system in sunflower plants exposed to ozone.

Sunflower plants subjected to a short-term fumigation with O(3) (150 ppb for 4 h repeated for 4 days) exhibited an increase in total ascorbate content, accompanied by a marked oxidation of ascorbate, leading to a decrease in its redox state, either at intracellular or extracellular level. O(3) exposure induced a rise in free extracellular peroxidase (POD) activity, assayed by syringaldazine as electron donor, as well as in the ionically and covalently cell wall bound PODs. On the contrary, the activity of both extracellular and intracellular guaiacol-POD did not show significant changes as a consequence of the pollutant exposure. The stimulation of syringaldazine-POD activities may be related to the effect of ozone on the growth of the cells, inducing an early senescence through the activation or acceleration of lignification processes. Beside, the reduced plasticity of the cell wall may oppose an unspecific mechanical resistance against the abiotic stress induced by the ozone exposure.

Journal Article↗
PubMed2000

[Report of a case of compartmental syndrome secondary to prolonged lithotomy position].

The lithotomy position is widely used in urological surgery to obtain adequate exposure of the perineal plane. It is used, for instance, for stenosis of the posterior urethra. Fortunately, it rarely gives rise to complications although if the operation takes a long time the patient may suffer various adverse reactions; these range from simple peroneal nerve distress to thromboembolism [1, 2] and the much more serious "compartmental syndrome" [2, 3, 4]. There is still debate about the best therapeutic approach to a lesion caused by prolonged muscle compression. Some suggest immediate fasciotomy, whether others hold out for conservative treatment. We report here a case of compartmental syndrome arising in a patient who had to remain the the lithotomy position for a long time, which responded well to conservative treatment.

Adult↗
PubMed1999

Microsatellite instability in thyroid tumours and tumour-like lesions.

Fifty-one thyroid tumours and tumour-like lesions were analysed for instability at ten dinucleotide microsatellite loci and at two coding mononucleotide repeats within the transforming growth factor beta (TGF-beta) type II receptor (TbetaRII) and insulin-like growth factor II (IGF-II) receptor (IGFIIR) genes respectively. Microsatellite instability (MI) was detected in 11 out of 51 cases (21.5%), including six (11.7%) with MI at one or two loci and five (9.8%) with MI at three or more loci (RER+ phenotype). No mutations in the TbetaRII and IGFIIR repeats were observed. The overall frequency of MI did not significantly vary in relation to age, gender, benign versus malignant status and tumour size. However, widespread MI was significantly more frequent in follicular adenomas and carcinomas than in papillary and Hürthle cell tumours: three out of nine tumours of follicular type (33.3%) resulted in replication error positive (RER+), versus 1 out of 29 papillary carcinomas (3.4%, P = 0.01), and zero out of eight Hürthle cell neoplasms. Regional lymph node metastases were present in five MI-negative primary cancers and resulted in MI-positive in two cases.

Adenocarcinoma, Follicular↗