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D Pellegrini

Publications and source records attributed to D Pellegrini.

At least 19 recordsLinked to original sources
PubMed2006

Evaluation of the fertilization capability of Paracentrotus lividus sea urchin storaged gametes by the exposure to different aqueous matrices.

Several experiments were performed to evaluate the fertilization capability of Paracentrotus lividus sea urchin gametes, which are usually used in fertilization tests, but which, until now, were employed only for few hours after spawning. The aim of this work is to evaluate the possibility of performing the bioassay for longer periods, employing 'conserved' gametes. As far as the method, the sperm was stored 'dry' at 4 degrees C; eggs were conserved in an antibiotic solution at 4 degrees C, and they were exposed both to copper solutions as reference toxicant and to aqueous matrices. The use of conserved gametes in the fertilization bioassay lead to EC50 values which were acceptable for about 3 days. Moreover, these experiments permitted to identify the limiting factor: the male gamete.

Animals↗
PubMed2006

Standardizing the methodology of sperm cell test with Paracentrotus lividus.

The sperm cell toxicity test with Paracentrotus lividus is widely used in Italy to assess the quality of complex aqueous matrices, but at present there is a shortage of standardized methodologies for the bioassay performance. In this work several critical points were considered, in order to verify the reliability of this bioassay and to improve its standardization. In particular, we have studied the differences in EC50 values at different sperm: egg ratios and with different quantities of gametes; the influence of sperm and eggs on fertilization rate and the influence of different recipients materials (plastic or glass). At the same time, it was evaluated if the obtained EC50 values were in accordance with those reported in literature. Experiments performed yielded EC50 values for copper ranging from 16.54 microg/l to 69.59 microg/l, with a total mean value +/- SD of 39.79 microg/l +/- 11.17. These data fit with those found in literature for other echinoid species. According to the same authors, poor fertilization was probably due to the effects on sperm and not on eggs, and moreover the linear regression analysis performed on each experiment suggested that the best amount of eggs to use in the test was 1000. Results from the comparison between the performance of the test in plastic or glass tubes showed an higher success in fertilization rate using borosilicate glass tubes.

Animals↗
PubMed2006

[Einstein's sign and other signs of aortic aneurysm].

Einstein's sign is a syndrome similar to an acute cholecystitis caused by the rupture of an abdominal aortic aneurysm. In this paper we describe the evolution of the disease that the physicist suffered till it led him to death. We also revise other signs which could be found in some patients with ruptured or dissected abdominal aortic aneurysm.

Aortic Aneurysm↗
PubMed2005

Mucilage impact on gorgonians in the Tyrrhenian sea.

The mucilage phenomenon has affected the Tuscan Archipelago since its first appearance (1991) in the Tyrrhenian Sea (Mediterranean Sea) [Innamorati M, Raddi E, Buzzichelli A, Melley S, Demoulin M. Le mucillaggini nel Mar Tirreno. Biol Mar Suppl Notiz 1992;1:23-26; Sartoni G, Sonni C. Tribonema marinum J. Feldmann e Acinetospora crinita (Carmichael) Sauvageau nelle formazioni mucillaginose bentoniche osservate sulle coste toscane nell'estate 1991. Inf Bot Ital 1991;23:23-30; Sartoni G, Cinelli F, Boddi S. Ruolo di Tribonema marinum J. Feldmann ed Acinetospora crinita (Carmichael) Sauvageau negli aggregati mucillaginosi bentonici delle coste toscane. Biol Mar Suppl Notiz 1993;1:31-34]. Seasonally, these mucous aggregates become very common in the benthic domain. The gorgonians are the most exposed organisms because they provide the best support for mucilage growth; indeed, their long branches positioned in orthogonally with respect to the current so as to capture plankton, also trap the filamentous mucilage present in the water. A 3-year monitoring programme at Capo Calvo (Island of Elba) was carried out in order to study the appearance of the mucilage phenomenon and its impact on three species of gorgonians (Eunicella cavolinii, Eunicella singularis, and Paramuricea clavata). The composition of mucilage and the gorgonian recovery capacity, when damaged, were investigated. During the first year of study (1999), no relevant interactions between gorgonians and mucilages were recorded. Instead, massive presence of mucilages causing different types of damage to the different gorgonian species investigated was recorded during the second (2000) and third year (2001). The type and the extent of the impact of mucilages also depend on the season. Three species of algae (Nematochrysopsis marina, Chrysonephos lewisii and Acinetospora crinita) constitute the principal components of the mucilaginous aggregates. In general, the first two species occur during the spring season, down to 20 m, while A. crinita occurs at greater depths. In July, when the mucilages reach their maximum development, C. lewisii is the predominant species. This species mainly affects E. cavolinii and E. singularis while A. crinita mainly affects P. clavata, which colonizes greater depths.

Animals↗
PubMed2004

Coupled modeling of cement/claystone interactions and radionuclide migration.

The interactions between cement and a clayey host-rock of an underground repository for intermediate-level radioactive waste are studied with the reactive transport code HYTEC for supporting performance assessment. Care is taken in using relevant time scales (100,000 years) and dimensions. Based on a literature review, three hypotheses are considered with respect to the mineralogical composition of the claystone and the neo-formed phases. In the long term, the pH is buffered for all hypotheses and important mineral transformations occur both in cement and the host-rock. The destruction of the primary minerals is localized close to the cement/claystone interface and is characterized by the precipitation of secondary phases with retention properties (illite, zeolite). However, beyond the zone of intense mineral transformations, the pore water chemistry is also disturbed over a dozen meters due to an attenuated but continuous flux of hydroxyl, potassium and calcium ions. Four interdependent mechanisms control the profile in the whole system: diffusion of the alkaline plume, mineralogical buffering, ion exchange and clogging of the pore space at the cement/claystone interface. The migration of a selected group of radionuclides (Cs, Ra, Tc and U) is explicitly integrated in the simulations of the strongly coupled system. Theoretical profiles of distribution coefficient (Kd) and solubility limit values are derived from the simulations, and their sensitivity with respect to the system evolution is estimated.

Aluminum Silicates↗
PubMed2003

[Carbon dioxide embolization: is it a complication of laparoscopic cholecystectomy? ].

The occurrence of pulmonary gas embolism in patients undergoing laparoscopic cholecystectomy is reported in the medical literature. Severe intraoperative complications or the patient's death were correlated to gas embolism during laparoscopic procedures. However, the careful retrospective study or the autoptic exam of such casualties have always showed an erroneus direct puncture of vessels or the straight insertion of the Veress needle into a parenchymal organ. It is obvious that the direct gas injection into a vein or into parenchymal organs is a primary cause of gas embolism, as well as the high flow insufflation of gas into the peritoneal cavity in concomitance with the lesion of major abdominal vessel's wall. Gas embolism may occur each time the vein internal pressure is lower than the external pressure and not only during a laparoscopic procedure when carbon dioxyde is inflated into the peritoneal cavity, but also during open surgery such as major liver resections, neurosurgery, vascular or cardiac surgery. The review of large series of laparoscopic cholecystectomies reported in the international literature, as well as our own clinical experience in this field, together with the results of laboratory animal studies based on the experimental insufflation or injection of carbon dioxyde, show that gas embolism must not be considered as a complication of laparoscopic surgery. Due to the above mentioned risks with the use of the Veress needle, the surgeon should revalue alternative means in creating the pneumoperitoneum.

Animals↗
PubMed2001

Distribution of chlorinated organic pollutants in harbor sediments of Livorno (Italy): a multivariate approach to evaluate dredging sediments.

Dredging is a very important procedure for harbor management. In Italy the guidelines for the offshore dumping of dredged materials are issued by the Ministry of Environment. They described a few steps of dredging activities, such as the sampling strategy, but do not deal with limits or guide-values for the chemical, physical and biological composition of the resulting sediments. The quality of dredged materials is mainly dependent on the presence of inorganic and organic pollutants. In particular, polychlorinated biphenyls (PCBs) and organo-chlorinated pesticides are seen as a high priority in marine environment by international organizations because of their persistence, toxicity and bioaccumulation capacity. In this article the presence of some PCBs and organo-chlorinated pesticides in sediment samples collected from the harbor of Livorno (Northern Tyrrhenian Sea) was investigated. The concentration of HCHs, Aldrin, Chlordanes, DDEs, DDTs, and PCBs in 12 representative sites ranged between <1 microg kg(-1) and 95, 19, 32, 35, 107, and 111 microg kg(-1), respectively. The application of univariate and multivariate statistical techniques, such as linear regression analysis and principal component analysis, to the experimental data showed a different distribution of PCBs in the two sediment layers. On the contrary, the vertical distribution of the other investigated pollutants was more homogeneous and affected by random variability. The multivariate approach was an important tool to establish more rational criteria for the management of dredged materials.

Conservation of Natural Resources↗
PubMed2001

Gastro-intestinal stromal tumor (GIST): case report.

Gastro-intestinal stromal tumors (GISTs), as currently defined, represent the largest category of primary non epithelial neoplasms of the gastrointestinal tract. They arise from mesenchymal cells located in the wall of the organ and show a remarkable variability in their differentiation pathways. For this reason there is relevant degree of confusion in their interpretation. On the basis of immunohistochemical and ultrastructural studies these neoplasms are divided into several categories: leiomyomas, schwannomas and less differentiated tumors referred as GIST. In the small bowel GIST are uncommon. Usually asymptomatic, they could be the cause of surgical emergencies like massive bleeding, obstruction, intussusception or perforation. Generally benign, an higher percentage of malignant cases are described in the small bowel. The Authors report a case of malignant GIST of the small intestine presented with bowel obstruction by ileal invagination. In this case, as usually it happens in malignant GIST, the final diagnosis was obtained by an abdominal surgical exploration.

Aged↗
PubMed2001

[Current developments in the treatment of acute generalised peritonitis].

Generalised acute peritonitis is a relatively frequently pathology which has always been extremely difficult to treat owing to the large number of complications. Considerable progress has been made over the past few years in the surgical treatment of these pathologies following the introduction of new materials accompanied by new techniques: continuous peritoneal lavage (CPL) and laparostomy are the best known. These techniques must be used in carefully selected patients. They allow a marked improvement in results: fewer cases of redo surgery; fewer local and general complications; shorter hospitalisation stay; fewer deaths. These results are possible because these techniques ensure a better cleansing of the peritoneal cavity, with easier removal of necrotic and purulent materials, the main cause of local and general complications.

Acute Disease↗
PubMed1989

Depressed mothers' judgments about their children: an examination of the depression-distortion hypothesis.

The belief that depressed mothers have distorted perceptions of their children's problems has gained considerable currency in recent years. The empirical basis for this belief at present amounts to little more than reliable demonstrations that depressed mothers tend to report more behavior problems in their children than do nondepressed mothers. An obvious alternative to the distortion interpretation is that depressed mothers are accurate about their children's behavior problems. We examined these competing models by comparing teachers' ratings of children with ratings provided by their mothers, who varied on the dimensions of depressed mood, depressed clinical state, and history of depression. Mothers' and teachers' ratings yielded substantially similar portraits of child behavior problems at the group level, with children of in-remission and in-episode mothers manifesting significantly higher levels of behavior problems than children of control mothers. Moreover, agreement between mothers and teachers was in the moderate range for all index groups and did not differ significantly from the mean level of mother-teacher agreement reported by other investigators based on unselected samples. The limitations of these findings and of earlier reports for assessing a depression----distortion influence on mothers' ratings of their children are considered.

Adult↗
PubMed1989

Age differences in coping: does less mean worse.

Previous research suggests that elderly people utilize fewer coping strategies than younger people. Some researchers suggest that these quantitative changes reflect decreases in the use of maladaptive strategies; others contend that they reflect decreases in the use of adaptive strategies by older adults. The present article reports the findings of three studies of coping in older people, two addressing coping with health problems, and the other addressing coping with moving. In all three studies, the number of self-reported coping strategies decreases with age. Results do not support the idea that decreases in the number of strategies imply decrements in the quality of coping, however: in two studies, age was unrelated to the effectiveness of strategies, in the third, effectiveness ratings were higher for older subjects. The need for evaluation of specific outcomes of coping strategies is discussed, along with the need for task-specific measurement of coping. It is proposed that decreases in the number of coping strategies reflect improved coping efficiency, rather than a deterioration of adaptational skills.

Adaptation, Psychological↗
PubMed1986

Content of quinolinic acid and of other tryptophan metabolites increases in brain regions of rats used as experimental models of hepatic encephalopathy.

The content of the tryptophan metabolites quinolinic acid (QUIN), 5-hydroxytryptamine (5-HT), and 5-hydroxyindoleacetic acid (5-HIAA) was measured in various brain areas of rats bearing a portocaval anastomosis (PCA) for 4 weeks, using mass fragmentography or HPLC. In these animals, the content of the excitotoxic compound QUIN increased by 75% in the cortex and 125% in the cerebellum. The content of 5-HT increased by 27% in the brainstem. No changes occurred in other brain areas. On the other hand, the content of 5-HIAA increased by 66% in the cortex, 65% in the caudate, 64% in the hippocampus, 120% in the diencephalon, and 185% in the brainstem. Probenecid administration caused a larger increase of 5-HIAA accumulation in various brain areas of PCA-bearing rats than in those of sham-operated controls. The cortical content of QUIN and 5-HIAA increased after administration of ammonium acetate (7 mmol/kg), whereas an equimolar amount of sodium acetate was inactive. These results confirm that profound changes in the disposition of tryptophan occur in the brains of experimental animals used as models of hepatic encephalopathy. Furthermore, this study adds the excitotoxic compound QUIN to the list of molecules possibly involved in the pathogenesis of this brain disorder.

Acetates↗
PubMed1986

Personal and social resources in children of patients with bipolar affective disorder and children of normal control subjects.

The authors examined the personal resources (social problem-solving ability, internal locus of control, self-esteem, and self-perceived competence) and social resources (social network structure and support) in 23 children of patients with bipolar affective disorder (probands) and 33 children of normal control parents. Positive resource profiles were related to psychiatric well-being in the offspring. Nondisordered probands, in particular, demonstrated a strikingly positive profile of personal resources as well as a wide range of peer, sibling, and other kin supporters. Disordered probands had a strikingly negative set of personal resources and a relatively greater reliance on nonkin adult supporters. The absence of a supportive best friend was associated with affective disorder across offspring groups.

Adolescent↗
PubMedDate not supplied

Diagnoses in school-age children of bipolar affective disorder patients and normal controls.

A family study of psychiatric diagnoses was performed in 29 children of bipolar patients and 37 children of normal controls, ages 6-17. There were no differences in major or minor affective diagnoses between the patient and control groups, but there was an increase of non-specific diagnoses in the patient group. Using DSM-III criteria, 10% of patients' children and 14% of controls' children had had at least one episode of major depression. This suggests that major depression in children is not familially related to adult bipolar major affective disorder. The observed prevalence of depression in childhood is increased when both direct interview of children and interview of parents are performed.

Adolescent↗
PubMedDate not supplied

Arteriovenous fistulas for hemodialysis created using a long-term absorbable suture: a safe solution and a measure to minimize myointimal hyperplasia.

BACKGROUND/AIMS: The goal of the therapeutic management of patients affected by end-stage renal disease (ESRD) is to maintain the vascular access (VA) as long as possible. Myointimal hyperplasia development in the vascular walls of arteriovenous fistulas (AVFs) is considered one of the most important factors responsible for procedure failure. These alterations could be linked to hemodynamic changes in the anastomosis and to the presence of the surgical suture itself. We report our preliminary experience, discussing the use and the possible benefits of an absorbable suture in polyglycolide trimethylene carbonate (PTC) in AVF creation. METHODS: Seventy-four AVFs were created as primary access for hemodialysis (HD), using PTC, over 4 years. Age, gender, ESRD etiology, artery and vein preoperative diameters, AVF survival outcome, and the number of AVFs created per year were recorded. The Kaplan-Meier method was used to analyze AVF survival rates. RESULTS: No dehiscences, pseudoaneurysms, or failures in the 'critical' period related to PTC absorption were recorded. Kaplan-Meier analysis was used to evaluate AVF survival; 12-month primary AVF survival (74.33%) and AVF failure (25.67%) rates, 9 'early' (8.22%) and 10 'late' failures (13.51%), and a 360-day mean survival were found. CONCLUSIONS: Our data indicate that PTC, a well known and widely used material for sutures in vascular surgery, is safe and effective in AVF creation. Potential advantages of PTC sutures are represented by a reduced myointimal hyperplasia formation in the AVF vascular walls, prolonging the AVF lifespan and avoiding re-interventions.

Journal Article↗