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Biomedical subjects

G Pellegrino

Publications and source records attributed to G Pellegrino.

18 recordsLinked to original sources
PubMed2004

Reproductive versus floral isolation among morphologically similar Serapias L. species (Orchidaceae).

Flowers of the Mediterranean orchid genus Serapias L. form small, dark tubes that vary among taxa in diameter and depth. Visiting insects use the floral tube as shelter and act as pollinators if they touch the sticky viscidium at the rear of the tube and remove the pollinarium. It has been assumed that floral tube size and shape limit access to the flowers and thus may act as a barrier to gene flow between different Serapias species. Here we investigated floral characters and nuclear microsatellite markers in populations belonging to three morphologically similar Serapias species to test whether these species show evidence for floral or reproductive isolation. We found strong overlap of floral traits between two species, suggesting that floral isolation is nonexistent between them. Microsatellite markers applied to the same populations were highly polymorphic and revealed clear genetic differentiation among all three species. These results suggest that reproductive isolation exists, despite the lack of floral isolation between two of the species. In contrast to morphological characters, diagnostic microsatellite alleles were found for all Serapias species. The microsatellite markers could thus provide a useful tool to identify Serapias species and further investigate evolutionary relationships in this fascinating orchid lineage.

Alleles↗
PubMed2003

Fine-scale phylogeographical analysis of Mediterranean Anacamptis palustris (Orchidaceae) populations based on chloroplast minisatellite and microsatellite variation.

The phylogeographical history of the rare marsh orchid Anacamptis palustris (Orchidaceae) was reconstructed using highly polymorphic chloroplast minisatellite and microsatellite loci. Allelic variation at chloroplast microsatellite loci was due to length variation in poly(A/T) repeats and was informative on a regional scale, but was not sufficient to unravel relationships among populations on a local geographical scale. The minisatellite locus, however, was found to be highly variable. Nine distinct repeat types were found and variation in repeat number occurred in five repeat types. The distribution of chloroplast haplotypes, combining microsatellite and minisatellite repeat type variation, provided a clear phylogeographical picture on a large geographical scale, whereas length variation in one highly polymorphic minisatellite repeat type provided fine-scale phylogeographical information. Mediterranean populations could be divided into four main lineages, a western European lineage, a northern and central Italian lineage, a well-isolated southern Italian (Apulian) lineage, and an eastern European lineage. Variation at the most variable minisatellite repeat type N revealed 19 alleles and allowed the study of seed-mediated gene flow and an estimation of the ratio of pollen to seed flow among neighbouring populations.

Base Sequence↗
PubMed2001

Coherent vortex extraction in 3D turbulent flows using orthogonal wavelets.

This Letter presents a wavelet technique for extracting coherent vortices from three-dimensional turbulent flows, which is applied to a homogeneous isotropic turbulent flow at resolution N = 256(3). The coherent flow is reconstructed from only 3%N wavelet coefficients that retain the vortex tubes, and 98.9% of the energy with the same k(-5/3) spectrum as the total flow. In contrast, the remaining 97%N wavelet coefficients correspond to the incoherent flow which is structureless, decorrelated, and whose effect can therefore be modeled statistically.

Journal Article↗
PubMed2001

Characterization of a minisatellite repeat locus in the chloroplast genome of Orchis palustris (Orchidaceae).

We describe the occurrence of a tandem repeat in the chloroplast genome of the marsh orchid, Orchis palustris. The repeat unit is an AT-rich, 16-bp sequence located in the chloroplast tRNALEU intron. Southern blot analysis confirmed that the O. palustris tRNALEU intron including the minisatellite locus has not been transferred to the nucleus, but is indeed located on the chloroplast genome. The 16-bp repeat unit was found to be present in all O. palustris accessions studied, as well as in the closely related O. laxiflora. Variation in repeat numbers among individuals was found in O. palustris from central and northern Italy; and this was consistently associated with a 13-bp sequence motif preceding the repeat. This motif was absent from O. palustris from southern Italy, Greece, and from O. laxiflora. In these accessions, no variation in repeat numbers was found. Our results suggest that the O. palustris chloroplast minisatellite locus evolved relatively recently, presumably in central Italy, and may represent a valuable marker for population genetic studies.

Base Composition↗
PubMed2001

Ganglioneuroma of parapharyngeal region.

In this article, we describe a case of ganglioneuroma observed in a 27-year-old woman. The tumor was found in an unusual location, the parapharyngeal space. The lesion was asymptomatic and was surgically excised after a fine-needle aspiration biopsy that was considered inadequate. The lesion measured 4 x 3 cm and was capsulated. Two distinct cells groups were identified: ganglion cells and Schwann cells placed in a loose myxoid stroma. Immunohistochemical stains (performed with the following monoclonal antibodies: high-molecular-weight cytokeratins, vimentin, neuron-specific enolase, neurofilaments, and S100) confirmed the diagnosis of ganglioneuroma. The pathologic findings and a review of recent literature are discussed.

Adult↗
PubMed2001

[Aneurysmatic fibrous histiocytoma: case report and reivew of the literature].

A case of aneurysmal fibrous histiocytoma is described. The patient is a 26-year-old man with a reddish nodule on the back, recently presenting a volume increase. The tumor was composed of fascicles of short spindle cells, histiocyte-like and inflammatory cells, and blood-filled spaces, mimicking vascular channels but lacking an endothelial lining. Immunohistochemical analysis (performed with the following monoclonal antibodies: smooth muscle actin, vimentin, desmin, CD-31, CD-34, CD-68) showed only vimentin positively on neoplastic cells. We discuss the differential diagnostic hypotheses and review the literature on this subject.

Adult↗
PubMed2000

Molecular analysis of orchid pollinaria and pollinaria-remains found on insects.

Direct observations of pollinator visits to orchids are often difficult and time consuming, especially in orchids with a deceptive pollination system where seed set is typically pollinator-limited. This lack of direct observations greatly inhibits our understanding of orchid-pollinator relationships and especially the degree of pollinator-specificity. Here we describe a molecular approach to the study of orchid-pollinator relationships based on the analysis of DNA recovered from pollinaria found on insects. The insects were collected from nectar-rich plants flowering near natural orchid populations, or taken from museum collections. Sequence analysis of the nuclear ribosomal ITS region allowed the identification of the orchid species or species-group from which the pollinaria originated. Four out of eight orchid-pollinator relationships established with this approach have not been reported previously, which highlights the value of molecular tools for the study of orchid pollination biology.

Animals↗
PubMed1999

Duodenal duplication cyst: MR imaging appearance.

The MR imaging appearance of a duodenal duplication cyst is reported. MR imaging confirmed the diagnosis suggested by ultrasound and CT scans. Fat-suppressed MR imaging before and after oral administration of the positive contrast agent Gd-DTPA was able to define tissue planes between the lesion and adjacent structures, such as the head of the pancreas, providing useful information for an accurate surgical approach. To our knowledge this is the first reported case of a duodenal duplication cyst in an adult demonstrated by MR imaging.

Adult↗
PubMed1998

[Magnetic resonance angiography of the epiaortic vessels of the thorax].

INTRODUCTION: Magnetic Resonance angiography (MRA) is an accurate and non-invasive diagnostic method to evaluate vascular disease. On the basis of its technological advancements, this technique has gained an important role in the diagnostic protocol of cerebral and cervical vascular diseases. Nonetheless, MRA efficacy changes in different anatomic districts as a consequence of the specific anatomy and flow features. Cardiac and respiratory artifact and different coil sensitivity also affect MRA results. For these reasons, intrathoracic epiaortic vessels are a difficult applications for MRA. MATERIAL AND METHODS: We examined 20 patients affected with epiaortic atherosclerosis with MRA, carried out with an 0.5 T MR unit (Vectra, GE). Examinations consisted of Phase Contrast (PC) 3D sequences (TR/TE/FA/Venc = 30/13/45/30-50), with 3 axes of flow encode, matrix 128 x 256, 2 mm partition thickness, and axial and/or coronal acquisition volume. The MRA was repeated after Gd-DTPA intravenous perfusion and a qualitative and quantitative evaluation of pre- and post-contrast results was performed. Specific parameters of evaluation were: angiographic contrast, contrast to noise ratio, saturation effect of longitudinal magnetization, contrast between arteries and veins. All patients were examined with Doppler US and angiography. MRA data were compared to angiography in order to establish MRA sensitivity and specificity. RESULTS AND CONCLUSIONS: PC sequences showed high accuracy in the examination of the proximal tract of epiaortic vessels; Gd-DTPA administration substantially improved MRA results. The perspectives of technological improvement will probably candidate PC MRA to be a valid alternative to US-Doppler and, perhaps, to angiographic study.

Adult↗
PubMed1989

[Use of propafenone in emergency therapy].

15 patients (10 M, 5 F; age 24-55) with paroxysmal supraventricular tachyarrhythmias (onset: 0.5-4 hours; 8 atrial tachycardias, 5 atrial fibrillation, 2 atrial flutter) were treated with 1 mg/kg i.v. propafenone. Propafenone terminated tachyarrhythmias in all patients during or within a few minutes after stopping infusion (mean conversion time: 6.4 min.). No significant changes in the main electrocardiographic parameters (QRS from 67 +/- to 80 +/- 21 msec., n.s.; QTc from 330 +/- 60 to 320 +/- 40 msec, n.s.), nor in blood pressure (from 128/82 +/- 21/10 to 135/83 +/- 11/8 mmHg, n.s.) were observed. No side effects appeared. In conclusion, propafenone proved to be effective and well tolerated in the acute treatment of supraventricular tachyarrhythmias.

Adult↗
PubMed1977

[Study on the relationship between meteorological-seasonal factors and acute vascular accidents].

Mortality from acute cardiovascular accidents has been studied in relation to the seasons in Naples, Milan and the rest of Italy. A constant parallel was noted between such deaths and the winter season. It is concluded that the meteoric-seasonal factor most responsible consists of the drop in temperature which could cause vascular spasm followed by an increase in systemic arterial pressure. It is personally considered that this is the most important pathogenetic mechanism in the majority of cases of acute cardiovascular accidents.

Acute Disease↗
PubMedDate not supplied

[Occupational injuries with biological risk].

The aim of the present study was to identify the way the occupational injuries with biological risk can happen in order to find the right measures of prevention and protection and to periodically verify their efficacy. The study started in January 1996 and ended in December 2001 and included 2750 subjects working in the sanitary field. A module (module A), was created to collect all the accident data. For every occupational injury with biological risk, a specific procedure is activated, including: Emergency Room, Sanitary Direction, Infective Diseases Division, Competent Physician. The injuries were classified, according to: sex, age, work qualify, division, object causing injury, modality, anatomical location, type of injury, working turn, and time phase. Most of the division underlined a higher risk the procedures that expose the subjects to accidental punctures with infected needle, such as injection therapy, blood tests, butterfly insertion and removal, etc. Old and bad attitudes, such as needle recapping are still used, even if the law is clear. None occupational injury showed serum conversion. It could be a consequence of the post exposition prophylaxis performed by the infectivologists and of the HBV prophylaxis.

Accidents, Occupational↗