Comparison of pollen gene flow among four European beech (Fagus sylvatica L.) populations characterized by different management regimes.

The study of the dispersal capability of a species can provide essential information for the management and conservation of its genetic variability. Comparison of gene flow rates among populations characterized by different management and evolutionary histories allows one to decipher the role of factors such as isolation and tree density on gene movements. We used two paternity analysis approaches and different strategies to handle the possible presence of genotyping errors to obtain robust estimates of pollen flow in four European beech (Fagus sylvatica L.) populations from Austria and France. In each country one of the two plots is located in an unmanaged forest; the other plots are managed with a shelterwood system and inside a colonization area (in Austria and France, respectively). The two paternity analysis approaches provided almost identical estimates of gene flow. In general, we found high pollen immigration (~75% of pollen from outside), with the exception of the plot from a highly isolated forest remnant (~50%). In the two unmanaged plots, the average within-population pollen dispersal distances (from 80 to 184 m) were higher than previously estimated for beech. From the comparison between the Austrian managed and unmanaged plots, that are only 500 m apart, we found no evidence that either gene flow or reproductive success distributions were significantly altered by forest management. The investigated phenotypic traits (crown area, height, diameter and flowering phenology) were not significantly related with male reproductive success. Shelterwood seems to have an effect on the distribution of within-population pollen dispersal distances. In the managed plot, pollen dispersal distances were shorter, possibly because adult tree density is three-fold (163 versus 57 trees per hectare) with respect to the unmanaged one.

Isolation and characterisation of bacterial colonies from seeds and in vitro cultures of Fraxinus spp. from Italian sites.

Culturable bacteria were isolated from seeds, embryos and contaminated in vitro cultures of ash (Fraxinus excelsior L., F. ornus L. and F. angustifolia L.) and were identified using morphological and molecular analyses. Fourteen morphologically distinct isolates were recovered from seeds of Fraxinus spp. 16S rDNA sequencing categorised these isolates into ten separate genera. Three strains isolated from contaminated in vitro cultures, Pantoea agglomerans, Staphylococcus succinus and Aerococcus viridans, were used for comparative analysis with isolates from seeds. Antibiotic sensitivity testing of the isolated contaminants, including phytotoxicity of antibiotics on in vitro cultures of ash, was also investigated. Phytotoxic effects on explants immersed in ampicillin or cultured on medium containing ampicillin were negligible, however tetracycline, either alone or in combination with other antibiotics, had phytotoxic effects. We conclude that ampicillin is a suitable antibiotic to limit the growth of contaminating bacteria during the in vitro culture of ash.

Geographic distribution of chloroplast variation in Italian populations of beech (Fagus sylvatica L.).

The distribution of chloroplast DNA (cpDNA) variation in Italian beech ( Fagus sylvatica L.) populations was studied using PCR-RFLP and microsatellite markers. In total, 67 populations were analysed, and 14 haplotypes were identified by combining the two marker types. A remarkable subdivision of cpDNA diversity in Italian beech was found, as indicated by a high level of genetic differentiation ( G(st)=0.855). The highest level of total haplotype diversity ( h(t)=0.822) was estimated for southern Italian populations. The highest number of haplotypes was found in the central-southern region of the peninsula. The nested clade analysis provided evidence for past fragmentation events that may have been occurred during the Quaternary glaciations and had a major role in defining the genetic structure of the central-southern Italian beech populations. Only one haplotype apparently spread towards the north of Italy along the Apennine chain and reached the Italian slope of the western part of the Alps (Maritime Alps, Liguria). All haplotypes found along the Apennines remained trapped in the Italian peninsula. Southern and central Italy represent hotspots of haplotype diversity for Italian beech.

Regular moderate intensity physical activity and blood concentrations of endogenous anabolic hormones and thyroid hormones in aging men.

BACKGROUND: Physical activity has been reported to affect endocrine function in elderly men. OBJECTIVE: To establish an association between regular moderate physical activity and endogenous anabolic hormone levels in healthy aging men. PARTICIPANTS: Twenty four middle-aged (57.4+/-4.7 years) and 24 elderly (68.3+/-2.6 years) physically active men who in the past 10 years had been regularly bicycling during leisure time were compared with 24 middle-aged (57.9+/-4.0 years) and 24 elderly (67.2+/-1.7 years) sedentary men. Groups did not differ for body composition. MEASUREMENTS: Serum dehydroepiandrosterone sulfate (DHEAS), insulin-like growth factor-I (IGF-1), free testosterone (FT), and thyroid hormone levels were assessed. RESULTS: In general, elderly men had lower IGF-1 (P<0.001), DHEAS (P=0.013), and triodothyronine levels (P<0.001) than their middle-aged counterparts. Independently of age, however, physically active men had on average higher IGF-1 (P=0.031), DHEAS (P=0.001), and triodothyronine serum levels (P<0.001) than sedentary men. FT and thyroid stimulating hormone (TSH) serum concentrations did not differ across age groups, but physically active men had lower TSH values than sedentary men (P=0.021). CONCLUSIONS: Our results suggest that, in aging men, regular moderate physical activity is associated with higher levels of IGF-1 and DHEAS levels and with thyroid function alterations.

Clay minerals protect bacteriophage PBS1 of Bacillus subtilis against inactivation and loss of transducing ability by UV radiation.

The effect of UV radiation on the survival of and transduction by phage PBS1 of Bacillus subtilis, free or adsorbed on the clay minerals montmorillonite (M) and kaolinite (K), was studied. After free or clay-associated phage (approximately 10(7) PFU.mL-1) was irradiated with UV light (254 nm) for 0, 1, 2, 5, 10, and 30 min and then allowed to infect B. subtilis FB300 (thiB4 metA29 argF4 Rfmr), the phage was titered, and Met+ transductants were enumerated on selective media. After 1 min of irradiation, the titer of free and clay-associated phage decreased significantly (approximately 1.6 times for free phage, and approximately 4.9 and 6.8 times for M and K, respectively), whereas the transduction frequency increased significantly (approximately 3 times for free phage and approximately 1.4 and 2.2 times for M and K, respectively). The titer and transduction frequency of clay-associated phage remain essentially constant between 1 and 10 min of irradiation, whereas the titer of free phage decreased by approximately 1 order of magnitude after 5 min of irradiation. When free phage was irradiated for 10 min, the titer and transduction frequency decreased by approximately 2 and 0.5 orders of magnitude, respectively, whereas 30 min of irradiation was necessary to obtain comparable decreases with clay-associated phage. These results indicated that phages are protected to some extent from UV radiation when adsorbed on clay minerals.

DNA as a possible target for antitumor ruthenium(III) complexes.

The interaction of two experimental ruthenium(III)-containing antitumor complexes-Na[trans-RuCl(4)(DMSO)(Im)] (NAMI) and dichloro(1,2-propylendiaminetetraacetate)ruthenium(III) (RAP)-with DNA was investigated through a number of spectroscopic and molecular biology techniques, including spectrophotometry, circular dichroism, gel shift analysis, and restriction enzyme inhibition. It was found that both complexes slightly alter DNA conformation, modify its electrophoretic mobility, and inhibit DNA recognition and cleavage by some restriction enzymes, though they were less effective than cisplatin in producing such effects. Notably, the effects produced by NAMI on DNA were much larger than those induced by RAP. Implications of these results for the mechanism of action of ruthenium(III) antitumor complexes are discussed.

Elevated plasma homocysteine levels in centenarians are not associated with cognitive impairment.

BACKGROUND: Previous reports have shown elevated plasma total homocysteine (tHcy) levels in elderly person with impaired cognition. OBJECTIVE: To study the association between cognitive status and plasma tHcy levels in centenarians. DESIGN: Cross-sectional survey. SETTING: Centenarians living in two northern Italian provinces. PARTICIPANTS: Thirteen cognitively normal centenarians, ten cognitively impaired not-demented centenarians, and 34 demented centenarians with a clinical diagnosis of Alzheimer's disease (AD). MEASUREMENTS: Blood levels of homocysteine's biological determinants vitamin B12, folate, and vitamin B6. RESULTS: Elevated plasma tHcy levels (>17 micromol/l) were common in the general population (77% of normal centenarians, 100% of cognitively impaired not-demented centenarians, 82% of AD centenarians). Demented centenarians had the lowest folate serum levels. Low or borderline vitamin B12 serum levels (<221 pmol/l) and low vitamin B6 plasma levels (<11.7 nmol/l) were found in 33 and 66% of all centenarians independently of cognitive status. Among demented centenarians only plasma tHcy correlated inversely with both serum vitamin B12 and folate. No significant difference was found for plasma tHcy levels among the three diagnostic groups, even after adjusting for B vitamin levels. CONCLUSIONS: Hyperhomocysteinemia is very common among centenarians, probably due to vitamin deficiencies, but does not seem to be associated with cognitive impairment.

Clay-nucleic acid complexes: characteristics and implications for the preservation of genetic material in primeval habitats.

The equilibrium adsorption of three nucleic acids: chromosomal DNA, supercoiled plasmid DNA, and 25S rRNA, on the clay minerals, montmorillonite (M) and kaolinite (K), were studied. Adsorption of the nucleic acid on the clays was rapid and maximal after 90 min of contact time. Chromosomal DNA was adsorbed to a greater extent than plasmid DNA and RNA, and the adsorption was also greater on M than on K. Adsorption isotherms were of the L type, and a plateau was reached with all the complexes, with the exception of chromosomal DNA adsorbed on M. To deterine where nucleic acids are adsorbed on clay minerals and the nature of the interaction, complexes were studied by X-ray diffraction (X-RD), electron microscopy, and Fourier transform infrared (FT-IR) spectroscopy. X-RD showed that nucleic acids did not penetrate the clay, indicating that the adsorption occurred primarily on the external surfaces of clay particles, as also suggested by electron microscopy observations. FT-IR spectra of clay-tightly bound nucleic acid complexes showed adsorption bands that indicate a variation of the nucleic acids status as a consequence of their adsorption on clay. Data obtained suggested that the formation of clay-nucleic acid complex could have an important role in the preservation of genetic material in primeval habitats.

Interaction between bacteriophage PBS1 and clay minerals and transduction of Bacillus subtilis by clay-phage complexes.

Bacteriophage PBS1 of Bacillus subtilis was rapidly adsorbed on montmorillonite (M) and kaolinite (K), and adsorption was maximal after 30min on both clays. There was no correlation between adsorption and the cation exchange capacity of the clays. Studies with sodium metaphosphate (a polyanion that interacts with positively charged sites on clay) indicated that positively charged sites on K were primarily responsible for the adsorption of the phage, whereas other mechanisms appeared to be involved in adsorption of the phage on M. X-ray diffraction and electron microscopic analyses showed that the phage partially intercalated M. Survival of the phage was increased by adsorption on the clays, and adsorbed phage maintained its ability to transduce bacterial cells for at least 30 days (the longest time studied) after the preparation of the clay-phage complexes. Electron microscopic observations indicated that transduction by the clay-phage complexes was primarily the result of the phage detaching from the clays in the presence of host cells.

Long term results of single session percutaneous ethanol injection in patients with large hepatocellular carcinoma.

BACKGROUND: The objective of this study was to evaluate the indications for percutaneous ethanol injection (PEI) performed in a single session under general anesthesia for treating patients with cirrhosis and large (tumors > 5 cm) hepatocellular carcinoma (HCC), and relevant survival curves. METHODS: Between November 1991 and November 1996, 108 patients were treated (a total of 128 procedures). They fell into 3 groups: 24 patients with single, encapsulated HCC measuring from 5-8.5 cm (Group A); 63 patients with single, infiltrating HCC measuring from 5-10 cm or multiple HCC (Group B); and 21 patients with advanced disease, either hepatic (Child's Class C) or neoplastic (symptomatic HCC or with portal thrombosis) type (Group C). The mean amount of ethanol injected was 62 mL. The average hospital stay was 3.8 days. The mean follow-up time was 40 months. RESULTS: The 1-, 2-, 3-, and 4-year survival rates were: 72%, 65%, 57%, and 44%, respectively, for Group A; 73%, 60%, 42%, and 18%, respectively, for Group B; and 46%, 25%, and 0%, respectively, for Group C. Mortality was 0.7% (bleeding from esophageal varices in a Child's Class C patient). The rate of major complications was 4.6% (1 case of peritoneal hemorrhage, 1 case of severe liver failure, 1 case of transient renal insufficiency, 1 case of peritoneal seeding, and 2 cases of infarctions of a segment adjacent to the tumor). CONCLUSIONS: Single session PEI has been proven to be a valid alternative in patients otherwise treated surgically or with transcatheter arterial chemoembolization who present with adverse prognostic factors or risks for these therapies, and may be an option for selected patients with advanced disease previously excluded from any therapy. Risk conditions are marked portal or pulmonary hypertension or esophageal varices at risk of bleeding, superficial tumors with severe coagulation disorders, hyperfibrinolysis, chronic renal insufficiency, and obstructive jaundice.

Intralesional ethanol in the treatment of unresectable liver cancer.

Percutaneous ethanol injection (PEI) under ultrasonography guidance has been widely tried in not advanced hepatocellular carcinoma (HCC). Ten years after the introduction of PEI, some conclusions of its indications can be drawn. In our series, 210 cirrhotic patients were treated; 141 with multisession PEI in an outpatient clinic, 57 with "single session" PEI under general anesthesia, and 12 with both. The 1-, 3-, and 5-year survival rates (by Kaplan-Meier method) were 953%, 65%, and 41% for Child class A patients with single HCC < or = 5 cm, and 88%, 47%, and 33% for patients with multiple HCC up to five lesions < or = 5 cm. In these patients the local recurrence rate was 15% and the new lesion rate at the 5-year follow-up was 74%. One death due to hemorrhage from esophageal varices in a Child class C patient treated by single session PEI occurred. The large number of cirrhotic patients demand for effective, safe, repeatable, low-cost treatment that can be offered at many centers. PEI meets all these requirements. PEI is proposed as the treatment of choice for the mentioned patients, excluding candidates for liver transplantation and surgical resection according to the predictive adverse factors currently in use. "Single session" technique widened the indications of traditional PEI to larger lesions.

Percutaneous ethanol injection of hepatic tumors: single-session therapy with general anesthesia.

OBJECTIVE: We studied the feasibility and the effectiveness of percutaneous ethanol injection, performed with general anesthesia in a single session, for treating malignant hepatic lesions. SUBJECTS AND METHODS: We treated 30 patients with sonographically guided percutaneous injection of ethanol. Twenty had hepatocellular carcinoma and cirrhosis, and 10 had hepatic metastases, principally from colon cancer. The mean volume of ethanol injected was 57 ml (range, 6-165 ml). RESULTS: CT showed complete necrosis (up to 8.2 cm) in seven of 10 patients with encapsulated hepatocellular carcinoma and about 90% necrosis in the remaining three patients. In four of these patients, the alpha-fetoprotein level fell from more than 200 ng/ml to less than 20 ng/ml during treatment. In 10 patients with infiltrating hepatocellular carcinoma, about 70-90% necrosis was achieved; in six of these patients, the alpha-fetoprotein level, which had been more than 200 ng/ml, decreased during treatment. In the 10 patients with metastases, more than 50% necrosis was always achieved. Levels of carcinoembryonic antigen decreased after treatment in all patients. In three patients who had cirrhosis with superficial hepatocellular carcinoma, peritoneal hemorrhage occurred but did not require transfusion. CONCLUSION: Our results show that percutaneous injection of ethanol in a single session with general anesthesia is feasible and effective and has several advantages over multisession therapy. These include shorter treatment time and the ability to treat larger and more numerous lesions.

[The clinico-echocardiographic aspects in acute pericarditis in a small child]. / Aspecte clinico-ecocardiografice în pericardita acuta la copilul mic.

The authors present a case of pericarditis in a 12-months-old child. They underlined the peculiarities of the onset and of the evolution.

Liver metastases: results of percutaneous ethanol injection in 14 patients.

Percutaneous ethanol injection (PEI) was performed under ultrasound (US) guidance in the outpatient department in 14 patients with 21 metastases 1.0-3.8 cm in diameter. The primary cancer was colorectal adenocarcinoma (seven patients), adenocarcinoma of the stomach (four patients), abdominal leiomyosarcoma (one patient), gastrinoma of unknown origin (one patient), and bronchial carcinoid (one patient). The indicators of therapeutic efficacy were US, computed tomography, fine-needle biopsy, and serologic markers. No complications occurred after a total of 175 treatment sessions. Complete response was obtained in 11 lesions, nine of which were less than 2 cm in diameter, and in all endocrine metastases (four lesions in two patients) with a maximum, recurrence-free follow-up of 38 months. Carcinoembryonic antigen values decreased in all patients but one for a 2-6-month period. The natural course of metastatic disease strictly limits the applicability of PEI, a local treatment. Single, metachronous, nonoperable metastasis of adenocarcinoma and endocrine metastases seem to be the only indications for PEI.

Percutaneous alcohol injection of portal thrombosis in hepatocellular carcinoma: a new possible treatment.

Hepatocellular carcinoma (HCC) with portal thrombosis is usually regarded as a contraindication for surgery and for percutaneous alcohol injection (PAI). For palliative purposes we used PAI in 4 patients with infiltrative HCC and segmental portal thrombosis. Ethanol, injected directly into the thrombus, diffused mostly along it. No complications emerged after 20 injections. In the first patient, who later received a liver transplant, the thrombus was completely necrotic. In the other patients, biopsies yielded only necrotic material: in two cases, progression of the thrombus was stopped at 4 and 12 months of follow-up, and in one case the thrombus shrank and remained as such 13 months later. This preliminary experience might broaden the scope of treatment for HCC.