A synecological study of communities with Santolina Corsica Jordan et Fourr.

Santolina Corsica is endemic to Corsica and Sardinia, with the main distributional area in central-northern Corsica. The distribution and floristic composition of the communities with S. Corsica were studied in relation to different environmental parameters such as altitude, geology and soil. The data was analysed by numerical methods: two-way indicator species (TWINSPAN) and Canonical Correspondence Analysis (CCA). TWINSPAN classification of 39 relevés revealed seven different community groups which were interpreted as belonging to a new subassociation of Stachydi-Genistetum in the alliance Teucrion mari (order Rosmarinetalia) and to Helichryso-Santolinetalia. The floristic composition of the communities studied was significantly correlated with the gradient of soil evolution. Another important factor was interpreted to be substrate coherence/inco- herence. The altitude/temperature gradient was not correlated with the floristic composition of the different communities. Several communities were regeneration stages after cultivation or grazing, and others seemed to be relatively unaffected by human activity. The ecological optimum for S. Corsica was in the former, in codominance with Helichrysum italicum

A synecological study of communities with Santolina Corsica Jordan et Fourr.

Santolina Corsica is endemic to Corsica and Sardinia, with the main distributional area in central-northern Corsica. The distribution and floristic composition of the communities with S. Corsica were studied in relation to different environmental parameters such as altitude, geology and soil. The data was analysed by numerical methods: two-way indicator species (TWINSPAN) and Canonical Correspondence Analysis (CCA). TWINSPAN classification of 39 relevés revealed seven different community groups which were interpreted as belonging to a new subassociation of Stachydi-Genistetum in the alliance Teucrion mari (order Rosmarinetalia) and to Helichryso-Santolinetalia. The floristic composition of the communities studied was significantly correlated with the gradient of soil evolution. Another important factor was interpreted to be substrate coherence/inco- herence. The altitude/temperature gradient was not correlated with the floristic composition of the different communities. Several communities were regeneration stages after cultivation or grazing, and others seemed to be relatively unaffected by human activity. The ecological optimum for S. Corsica was in the former, in codominance with Helichrysum italicum

The syntaxonomic position of Santolina etrusca - multivariate analysis

The results of multivariate analysis of the syntaxonomic role of Santolina etrusca (Lacaita) Marchi et D'Amato, a species endemic to Tyrrhenian central Italy, are reported. Classification was performed by polythetic divisive analysis using two-way indicator species (TWINSPAN). Ordination analysis was performed by correspondence analysis (CA). Classification and ordination showed that although Santolina etrusca grows prevalently in communities of Rosmarinetalia Br.-Bl. ex Molinier 1934, it is ecologically correlated and associated with entities of unstable nitrophilous communities subject to frequent disturbance belonging to an order, Helichryso-Santolinetalia Peinado and Martinez-Parras 1984, with western eumediterranean distribution. However it does not have a well defined sociological role, as it is constant in all community groups

Nonischemic left ventricular scar and cardiac sudden death in the young

Nonischemic Left Ventricular Scar (NLVS) is a pattern of myocardial injury characterized by midventricular and/or subepicardial gadolinium hyper enhancement at cardiac magnetic resonance, in absence of significant coronary artery disease. We aimed to evaluate the prevalence of NLVS in juvenile sudden cardiac death and to ascertain its aetiology at autopsy. We examined 281 consecutive cases of sudden death of subjects aged 1 to 35 years of age. NLVS was defined as a thin, grey rim of subepicardial and/or midmyocardial scar in the left ventricular free wall and/or the septum, in absence of significant stenosis of coronary arteries. NLVS was the most frequent finding (25%) in sudden deaths occurring during sports. Myocardial scar was localized most frequently within the left ventricular posterior wall, and affected the subepicardial myocardium, often extending to the midventricular layer. On histology it consisted of fibrous or fibro-adipose tissue. Right ventricular involvement was always present. Patchy lymphocytic infiltrates were frequent. Genetic and molecular analyses clarified the aetiology of NLVS in a subset of cases. ECG recordings were available in over half of subjects. The most frequent abnormality was the presence of low QRS voltages (< 0,5 mV) in limb leads. In serial ECG tracings, the decrease in QRS voltages appeared, in some way progressive. NLVS is the most frequent morphologic substrate of juvenile cardiac sudden death in sports. It can be suspected based on ECG findings. Autopsy study and clinical screening of family members are required to differentiate between Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia and chronic acquired myocarditis

Mycocoenology in Abies alba Miller woods of central-southern Tuscany (Italy)

Numerous reports indicate that fir woods in central and northern Europe have recently been damaged by increasing pollution. It has been demonstrated that fungi can be good bioindicators of forest health status. In polluted areas the production of fruit bodies generally declines and the fungal biodiversity, especially of symbiotic species, is reduced. Here we report the results of a survey of the fungal and plant communities in woods of Abies alba Miller in central-southern Tuscany, already studied in the past. Certain changes were observed in the study areas, but they seem more likely to be due to other factors than pollution, such as the weather conditions, the age and natural evolution of the forests towards their climax

Anomalous Kv 7 channel activity in human malignant hyperthermia syndrome unmasks a key role for H2 S and persulfidation in skeletal muscle.

BACKGROUND AND PURPOSE: Human malignant hyperthermia (MH) syndrome is induced by volatile anaesthetics and involves increased levels of cystathionine β-synthase (CBS)-derived H2 S within skeletal muscle. This increase contributes to skeletal muscle hypercontractility. Kv 7 channels, expressed in skeletal muscle, may be a molecular target for H2 S. Here, we have investigated the role of Kv 7 channels in MH. EXPERIMENTAL APPROACH: Skeletal muscle biopsies were obtained from MH-susceptible (MHS) and MH-negative (MHN) patients. Immunohistochemistry, RT-PCR, Western blot, and in vitro contracture test (IVCT) were carried out. Development and characterization of primary human skeletal muscle cells (PHSKMC) and evaluation of cell membrane potential were also performed. The persulfidation state of Kv 7 channels and polysulfide levels were measured. KEY RESULTS: Kv 7 channels were similarly expressed in MHN and MHS biopsies. The IVCT revealed an anomalous contractility of MHS biopsies following exposure to the Kv 7 channel opener retigabine. Incubation of negative biopsies with NaHS, prior to retigabine addition, led to an MHS-like positive response. MHS-derived PHSKMC challenged with retigabine showed a paradoxical depolarizing effect, compared with the canonical hyperpolarizing effect. CBS expression and activity were increased in MHS biopsies, resulting in a major polysulfide bioavailability. Persulfidation of Kv 7.4 channels was significantly higher in MHS than in MHN biopsies. CONCLUSIONS AND IMPLICATIONS: In skeletal muscle of MHS patients, CBS-derived H2 S induced persulfidation of Kv 7 channels. This post-translational modification switches the hyperpolarizing activity into depolarizing. This mechanism can contribute to the pathological skeletal muscle hypercontractility typical of MH syndrome

The syntaxonomic position of Santolina etrusca - multivariate analysis

The results of multivariate analysis of the syntaxonomic role of Santolina etrusca (Lacaita) Marchi et D'Amato, a species endemic to Tyrrhenian central Italy, are reported. Classification was performed by polythetic divisive analysis using two-way indicator species (TWINSPAN). Ordination analysis was performed by correspondence analysis (CA). Classification and ordination showed that although Santolina etrusca grows prevalently in communities of Rosmarinetalia Br.-Bl. ex Molinier 1934, it is ecologically correlated and associated with entities of unstable nitrophilous communities subject to frequent disturbance belonging to an order, Helichryso-Santolinetalia Peinado and Martinez-Parras 1984, with western eumediterranean distribution. However it does not have a well defined sociological role, as it is constant in all community groups

Influence of some geomorphological and vegetation features of river terraces on cover and density of Santolina etrusca (Lacaita) Marchi & d’Amato

The relationship between density and cover of Santolina etrusca, a plant species endemic to central Italy, and some ecological and geomorphological features of river terraces were studied by univariate and multivariate analysis. The results showed that S. etrusca achieves maximum density and cover on the second river terrace occasionally disturbed by flooding and with chamaephytic vegetation. On the first terrace its distribution is limited by frequent flooding and on the third by competition. Since S. etrusca grows on all the terraces considered in this study, it is a poor indicator of the gradient of disturbance due to flooding. It is not highly adapted to disturbance by flooding nor to competition ; nor is it potentially dominant if undisturbed.Nous avons étudié par analyses statistiques univariées et multivariées la relation entre la densité et le recouvrement de Santolina etrusca, plante endémique du centre de l’Italie et quelques caractéristiques écologiques et géomorphologiques des terrasses fluviales. Il résulte de l’analyse que S. etrusca présente les valeurs maximales de densité et de recouvrement sur la deuxième terrasse fluviale, perturbée sporadiquement par les crues et avec une végétation de garrigue. Sur la première terrasse, la densité de l'espèce est réduite par les fréquentes crues, alors que sur la troisième terrasse cette densité est réduite par la plus grande compétition interspécifique. S. etrusca pousse donc dans toutes les terrasses étudiées et elle n’est pas une indicatrice valable de l’impact des crues. En outre, cette espèce ne semble ni très adaptée à ce type de perturbation, ni compétitive quand les perturbations cessent.Angiolini Claudia, De Dominicis Vincenzo. Influence of some geomorphological and vegetation features of river terraces on cover and density of Santolina etrusca (Lacaita) Marchi & d’Amato. In: Ecologia mediterranea, tome 24 n°1, 1998. pp. 33-41