Modeling Phenological Phases across Olive Cultivars in the Mediterranean

Modeling phenological phases in a Mediterranean environment often implies tangible challenges to reconstructing regional trends over heterogenous areas using limited and scattered observations. The present investigation aimed to project phenological phases (i.e., sprouting, blooming, and pit hardening) for early and mid-late olive cultivars in the Mediterranean, comparing two phenological modeling approaches. Phenoflex is a rather integrated but data-demanding model, while a combined model of chill and anti-chill days and growing degree days (CAC_GDD) offers a more parsimonious and general approach in terms of data requirements for parameterization. We gathered phenological observations from nine experimental sites in Italy and temperature timeseries from the European Centre for Medium-Range Weather Forecasts, Reanalysis v5. The best performances of the CAC_GDD (RMSE: 4 days) and PhenoFlex models (RMSE: 5-9.5 days) were identified for the blooming and sprouting phases of mid-late cultivars, respectively. The CAC_GDD model was better suited to our experimental conditions for projecting pit hardening and blooming dates (correlation: 0.80 and 0.70, normalized RMSE: 0.6 and 0.8, normalized standard deviation: 0.9 and 1.0). The optimization of the principal parameters confirmed that the mid-late cultivars were more adaptable to thermal variability. The spatial distribution illustrated the near synchrony of blooming dates between the early and mid-late cultivars compared to other phases.

Control of postharvest diseases caused by Penicillium spp. with myrtle leaf phenolic extracts: in vitro and in vivo study on mandarin fruit during storage

BACKGROUND

In the postharvest handling of horticultural commodities, plant extracts with fungicidal activity are a valid alternative to synthetic fungicides. The fungicidal activity of myrtle leaf extracts from eight cultivars was studied in vitro against Penicillium digitatum, Penicillium italicum, and Penicillium expansum and on artificially inoculated mandarins with green and blue molds during storage for 12 days at 20 °C and 90% RH.

RESULTS

Hydroxybenzoic acids, hydrolysable tannins, and flavonols were identified by high-performance liquid chromatography (HPLC). Despite sharing the same phenolic profile, extracts of eight myrtle cultivars significantly differed in the concentration of phenolics. Hydrolysable tannins are the principal subclass representing nearly 44.9% of the total polyphenols, whereas myricitrin was the most abundant flavonol in all cultivars. Myrtle extracts strongly inhibited conidial germination of the pathogens tested, although the greatest efficacy was observed against P. digitatum. At a concentration of 20 g L^-1 , all the extracts completely inhibited fungi growth; only 'Angela', 'Tonina' and 'Grazia' extracts were effective at lower concentrations (15 g L^-1 ). On inoculated fruit, myrtle extracts significantly controlled rot development. As a preventive treatment, 'Ilaria' and 'Maria Rita' extracts significantly reduced the rate of fruit with green mold decay lesions. When applied as a curative treatment, all the exacts decreased the incidence of decay. Against P. italicum, all the extracts applied as preventive treatments controlled decay effectively, while as curative treatment some of the extracts were not effective. All the extracts reduced the size of the infected areas.

CONCLUSION

The results propose myrtle extracts as a possible natural alternative to synthetic fungicides. © 2021 Society of Chemical Industry.

Natural Compounds and PCL Nanofibers: A Novel Tool to Counteract Stem Cell Senescence

Tissue homeostasis mainly depends on the activity of stem cells to replace damaged elements and restore tissue functions. Within this context, mesenchymal stem cells and fibroblasts are essential for maintaining tissue homeostasis in skin, in particular in the dermis. Modifications in collagen fibers are able to affect stem cell features. Skin properties can be significantly reduced after injuries or with aging, and stem cell niches, mainly comprising extracellular matrix (ECM), may be compromised. To this end, specific molecules can be administrated to prevent the aging process induced by UV exposure in the attempt to maintain a youngness phenotype. NanoPCL-M is a novel nanodevice able to control delivery of Mediterranean plant myrtle (Myrtus communis L.) extracts. In particular, we previously described that myrtle extracts, rich in bioactive molecules and nutraceuticals, were able to counteract senescence in adipose derived stem cells. In this study, we analyzed the effect of NanoPCL-M on skin stem cells (SSCs) and dermal fibroblasts in a dynamic cell culture model in order to prevent the effects of UV-induced senescence on proliferation and collagen depot. The BrdU assay results highlight the significantly positive effect of NanoPCL-M on the proliferation of both fibroblasts and SSCs. Our results demonstrate that-M is able to preserve SSCs features and collagen depot after UV-induced senescence, suggesting their capability to retain a young phenotype.

Expression of Structural Flavonoid Biosynthesis Genes in Dark-Blue and White Myrtle Berries (Myrtus communis L.)

Within the myrtle (Myrtus communis L.) species, different genotypes may produce dark-blue berries or white berries depending on the peel color upon ripening. One dark-blue cultivar and one white myrtle cultivar were used to study the molecular mechanisms underlying flavonoid biosynthesis. The relative expression levels of common (PAL, CHS, CHI, DFR and LDOX) and specific (FLS, ANR, LAR and UFGT) flavonoid genes were analyzed during fruit development by means of quantitative real-time polymerase chain reaction (RT-qPCR). Moreover, the anthocyanin content was determined, and it showed an increase with the ripening of the berries of the dark-blue cultivar. The results showed an increased transcript abundance of PAL, CHI, DFR, LDOX and UFGT gene expression in the dark-blue cultivar compared to the white one, as well as a strong positive correlation between the changes in gene expression and anthocyanin accumulation. The transcript levels of UFGT showed sharp increases at 150 and 180 days after full blooming (DAF) in the dark-blue cultivar, which corresponded with anthocyanin accumulation. However, ripening seemed to modulate the expression of genes implicated in flavonols (i.e., FLS) and flavan-3-ols (i.e., LAR and ANR) in different manners. However, whereas FLS transcript accumulation increased at the end of the ripening period in the dark-blue cultivar, LAR and ANR gene expression decreased in both cultivars.

Smart Nanofibers with Natural Extracts Prevent Senescence Patterning in a Dynamic Cell Culture Model of Human Skin

Natural cosmetic products have recently re-emerged as a novel tool able to counteract skin aging and skin related damages. In addition, recently achieved progress in nanomedicine opens a novel approach yielding from combination of modern nanotechnology with traditional treatment for innovative pharmacotherapeutics. In the present study, we investigated the antiaging effect of a pretreatment with Myrtus communis natural extract combined with a polycaprolactone nanofibrous scaffold (NanoPCL-M) on skin cell populations exposed to UV. We set up a novel model of skin on a bioreactor mimicking a crosstalk between keratinocytes, stem cells and fibroblasts, as in skin. Beta-galactosidase assay, indicating the amount of senescent cells, and viability assay, revealed that fibroblasts and stem cells pretreated with NanoPCL-M and then exposed to UV are superimposable to control cells, untreated and unexposed to UV damage. On the other hand, cells only exposed to UV stress, without NanoPCL-M pretreatment, exhibited a significantly higher yield of senescent elements. Keratinocyte-based 3D structures appeared disjointed after UV-stress, as compared to NanoPCL-M pretreated samples. Gene expression analysis performed on different senescence associated genes, revealed the activation of a molecular program of rejuvenation in stem cells pretreated with NanoPCL-M and then exposed to UV. Altogether, our results highlight a future translational application of NanoPCL-M to prevent skin aging.

Mineral composition of Atriplex halimus plant as influenced by genotype and thermal regime

Atriplex halimus grows in humid and saline warm regions of Mediterranean area showing high adaptability but less information is available on resistance to chilling temperatures.Potted plants of five clones (MAR1, GIO1, SAN3, PAL1, and FAN3) were cultivated during 30 months in four localities (Oristano, Tempio, Sassari, and Villasor). Every 6 months, leaves, stems and roots of plants were the object of mineral composition analysis (N, P, Na, K, Ca, Mg, Cu, Zn, Fe, and Mn). During the experiment, air temperature was recorded and hour degrees sums calculated for thresholds ranging from 0 °C to 35 °C.Leaves showed highest content of all elements, with the exception of iron.Plants showed ability to accumulate mineral elements in a synergic or antagonistic way. Accumulation of chilling hour degrees positively correlated with calcium in leaves and stems, and with manganese in the whole plant. Sodium in leaves, instead, was favored by high temperatures, which are unfavorable to nitrogen accumulation in roots. Magnesium accumulation in leaves and roots enhanced with moderately high temperatures. Two of the tested clones (GIO1 and SAN3) showed a relative low adaptability to the coldest conditions. The other three clones provided better performances with the best behavior of PAL1.

Myrtus Polyphenols, from Antioxidants to Anti-Inflammatory Molecules: Exploring a Network Involving Cytochromes P450 and Vitamin D

Inflammatory response represents one of the main mechanisms of healing and tissue function restoration. On the other hand, chronic inflammation leads to excessive secretion of pro-inflammatory cytokines involved in the onset of several diseases. Oxidative stress condition may contribute in worsening inflammatory state fall, increasing reactive oxygen species (ROS) production and cytokines release. Polyphenols can counteract inflammation and oxidative stress, modulating the release of toxic molecules and interacting with physiological defenses, such as cytochromes p450 enzymes. In this paper, we aimed at evaluating the anti-inflammatory properties of different concentrations of Myrtus communis L. pulp and seeds extracts, derived from liquor industrial production, on human fibroblasts. We determined ROS production after oxidative stress induction by H₂O₂ treatment, and the gene expression of different proinflammatory cytokines. We also analyzed the expression of CYP3A4 and CYP27B1 genes, in order to evaluate the capability of Myrtus polyphenols to influence the metabolic regulation of other molecules, including drugs, ROS, and vitamin D. Our results showed that Myrtus extracts exert a synergic effect with vitamin D in reducing inflammation and ROS production, protecting cells from oxidative stress damages. Moreover, the extracts modulate CYPs expression, preventing chronic inflammation and suggesting their use in development of new therapeutic formulations.

Chemical Composition of Myrtle (Myrtus communis L.) Berries Essential Oils as Observed in a Collection of Genotypes

Myrtle (Myrtus communis L.) is a shrub spontaneously growing in the Mediterranean area. The leaf and fruit content of essential oils and phenolic compounds justify the wide use of the plant as medicinal and aromatic. Because of overexploitation of wild plants, a domestication process is in progress in different regions and the influence of the genotype variability on the chemical composition of fruit essential oils may be useful to breeding programs. Consequently, the analysis performed on a selected group of candidate clones growing in the same field collection in Sardinia is the object of this report. Forty-seven selections provided fully ripe fruits for essential oil extraction by hydrodistillation and Gas Chromatography-Mass Spectrometry (GC-MS) analysis. Only five candidate clones showed white fruits. The highest yield of essential oil was observed in the LAC31 genotype with 0.55 g·kg-1, while the samples BOS1, MON5, RUM4, RUM10, V4 and V8 showed values above 0.20 g·kg-1 and most of the genotypes under 0.10 g·kg-1. Geranyl acetate was the compound with the highest relative abundance. The second compound for relative abundance was the 1,8-cineole. Other compounds with high relative abundance were α-terpinyl acetate, methyleugenol, linalool, α-terpineol, β-caryophyllene, α-humulene, Trans-caryophyllene oxide, and humulene epoxide II.

Water potential in soil and Atriplex nummularia (phytoremediator halophyte) under drought and salt stresses

Atriplex nummularia is a halophyte widely employed to recover saline soils and was used as a model to evaluate the water potentials in the soil-plant system under drought and salt stresses. Potted plants grown under 70 and 37% of field capacity irrigated with solutions of NaCl and of a mixture of NaCl, KCl, MgCl₂ and CaCl₂ reproducing six electrical conductivity (EC): 0, 5, 10, 20, 30, and 40 dS m^-1. After 100 days, total water (Ψ_{w, plant}) and osmotic (Ψ_{o, plant}) potentials at predawn and midday and Ψ_{o, soil}, matric potential (Ψ_{m, soil}) and Ψ_{w, soil} were determined. The type of ion in the irrigation water did not influence the soil potential, but was altered by EC. The soil Ψ_o component was the largest contributor to Ψ_{w, soil}. Atriplex is surviving ECs close to 40 dS m^-1 due to the decrease in the Ψ_w. The plants reached a Ψ_w of approximately -8 MPa. The water potentials determined for different moisture levels, EC levels and salt types showed huge importance for the management of this species in semiarid regions and can be used to recover salt affected soils.

Influence of postharvest hot-dip fungicide treatments on Redblush grapefruit quality during long-term storage/Efecto de los tratamientos fungicidas postcosecha por inmersión en agua caliente sobre la calidad del pomelo Redblush durante el almacenamiento en frío

The efficacy of postharvest hot-dip treatment on Redblush grapefruit was investigated by 3-min dips in water at 50°C and 20°C, with and without 1500 ppm imazalil (IMZ) or thiabendazole (TBZ). Fruits were stored for 16 weeks in cold rooms at 8°C and then held at 20°C for 1 week to simulate shelf life. IMZ and TBZ treatment at 20°C considerably reduced the incidence of chilling injury (by about 50-60%) and the percentage (by 20%) of fungal infections. The effectiveness of the two fungicides was found to be considerably increased at 50°C. However, the beneficial effect of hot-dip treatment was noted, whether or not associated with the use of fungicides. The chilling index was threefold lower in fruit dipped in water at 50°C. Similar results were obtained by IMZ treatment and mold decay was decreased by about 50%. IMZ treatment at 50°C proved to be phytotoxic, thus resulting in reddish peel pitting, starting on the fourth week of storage. No further detrimental heat-related effect was detected in the remaining cases. Fruit treated with the two fungicides exhibited no significant differences in respiration rate under cold storage, when compared to control. By contrast, by the end of shelf life, sharply increased values were found in fruit treated with IMZ at 20°C. Endogenous ethylene production and internal quality attributes (juice%, total soluble solid content, juice acidity, and ripening index) did not reveal important differences between treatments. Ethanol concentration in the juice was remarkably lower in fruit treated with the two fungicides, whereas differences due to dip temperature were negligible in most cases.

Influence of temperature on biomass production of clones of Atriplex halimus

A very effective tool to combat desertification is revegetation. Promising species for this purpose are the evergreen shrubs of the genus Atriplex. The objective of the research was to study the growing responses of Atriplex halimus under different thermal regimes and to evaluate the biomass accumulation of selected clones. The test was carried out in four sites of Sardinia Island (Italy) characterized by different latitude, altitude and air temperature trends along the year. In every site, potted plants of five clones of A. halimus were compared for biomass production as measured by linear growth of plants (central axis and secondary shoots), as well as by dry weight of leaves, shoots and roots per plant. Correlations between sums of hour-degrees under or above the thresholds of critical air temperatures, comprised between 0 and 35 °C, and the plant growth indicators were analysed. Differences among the five clones, with regard to the influence of low temperatures on plant growth and on the biomass production were evaluated. Among five tested clones, GIO1 and SAN3 resulted more sensitive to low temperatures. Clones MAR1, PAL1 and FAN3 resulted less sensitive to low temperatures and in the site characterized by the lowest minimum temperatures also have shown greater adaptability and thus biomass growth in the observed period. The clone PAL1 showed a lower shoot/root biomass ratio as adaptation to cold temperature, and the clone FAN3, the opposite behaviour and a general preference to temperate thermal regimes.

Effect of water stress on growth, water use efficiency and gas exchange as related to osmotic adjustment of two halophytes Atriplex spp

Atriplex halimus L. is known in the Mediterranean basin and along the coastal areas of Sardinia for its adaptability to salinity, although less information is available on the resistance of this species to water stress in absence of salinity. The effect of water stress on growth and water utilisation was investigated in two Atriplex species: A. halimus originating of south Sardinian island and the exotic species Atriplex nummularia Lindl., originating in Australia and widely used in land restoration of arid areas. Water stress was applied to young plants growing in 20L pots with a sufficient water reserve to store a potentially sufficient water reserve to maintain substrate near to field capacity (30%) between irrigations. Watering was at 70% (control) or 40% (stress) of field capacity. In order to simulate the grazing by livestock, four plant biomass cuttings were conducted at times T0, T1, T2 and T3, corresponding to one cutting at the end of well watered phase (T0) before water stress induction, two cuttings after cycles of 5 weeks each during full summer (T1) and late summer (T2) and one cutting during autumn (T3). All plants remained alive until the end of treatment although growth was strongly reduced. Leaf dry weight (DW) and water use efficiency (WUE) were determined for all cuttings; relative water content (RWC), turgid weight:dry weight ratio (TW:DW), water potential (Ψw), osmotic potential (Ψs), CO2 assimilation, osmotic adjustment (OA), abscisic acid (ABA) and sugar accumulation were determined for the late summer cutting at T2. Water stress induced a decrease in DW, RWC, Ψw, Ψs, TW:DW and CO2 assimilation for both species, but an increase in WUE expressed in terms of dry matter production and a high accumulation of ABA and total sugars mainly for A. halimus. This suggests a more developed adaptive mechanism in this selection. Indeed, the clone was selected from the southern part of the island, where natural populations of saltbush are more exposed to abiotic stresses, mainly the water stress generated not by salinity. A. nummularia showed a greater OA and a positive net solute accumulation as than A. halimus, suggesting that water stress resistance in A. halimus is linked to a higher WUE rather than a greater osmotic adjustment.

Effect of maturation and cold storage on the organic acid composition of myrtle fruits

BACKGROUND

The effect of maturation and senescence on the chemical composition of two myrtle cultivars was studied in mature, overripe and cold-stored fruits in order to find the most appropriate harvesting period and best storage technology for industrial purposes.

RESULTS

After cold storage at 10 °C for 15 days, berry weight loss ranged from 12.5 to 18.4%, with the highest losses in less mature fruits. Titratable acidity decreased during maturation and cold storage in both cultivars. Reducing and total sugars increased during maturation. Anthocyanin concentration increased during maturation but decreased in overripe berries. The major organic acids in myrtle fruits were quinic, malic and gluconic acids. In fresh and cold-stored fruits, malic acid rose to 3 g kg(-1) and decreased thereafter. Quinic acid peaked at 90 or 120 days after bloom and decreased thereafter to reach low concentrations in mature fruits.

CONCLUSION

Cold storage for 15 days at 10 °C does not affect myrtle fruit quality for liqueur production. Anthocyanin concentration is the best indicator of harvest time for industrial purposes. Gluconic acid concentration is high in mature, overripe and cold-stored berries. This parameter can be used as a marker of the onset of fruit senescence.

Nitrate estimation in the denitrifying post-filtration unit of a municipal wastewater treatment plant: the Viikinmäki case

In this work we present and discuss the design of an array of soft-sensors to estimate the nitrate concentration in the denitrifying post-filtration unit at the Viikinmäki wastewater treatment plant in Helsinki (Finland). The developed sensors aim at supporting the existing hardware analyzers by providing a reliable back-up system in case of malfunction of the instruments. In the attempt to design easy to implement and interpretable sensors, computationally light linear models have been considered. However, due to the intrinsic nonlinearity of the process, also nonlinear but still computationally affordable models have been considered for comparison. The experimental results demonstrate the potential of the developed soft-sensors and the possibility for an on-line implementation in the plant's control system as alternative monitoring devices.

Wastewater treatment modelling in practice: a collaborative discussion of the state of the art

Three consulting teams conducted independent modelling projects for three different wastewater treatment plants ranging in size from approximately 113,800 m(3)/d (30 mgd) to 530,000 m(3)/d (140 mgd), in different parts of the world (USA and Finland). The plants have different treatment objectives ranging from nitrification and partial denitrification (nitrate plus nitrite <8.7 mg/L) to enhanced nutrient removal (total nitrogen <3 mg/L, total phosphorus <0.3 mg/L). Commonly-used models were applied in the case studies, including ASM3 (using the GPS-X simulator), New General (using GPS-X), Dold (using BioWin), and a variation of the Dold model methanol degradation capabilities (NGmeth within GPS-X). The authors compare and contrast the modelling approaches taken, including calibration and validation approaches, sensitivity analyses, and the application of results to full-scale studies, designs and operations. Despite several differences between the approaches, there are many similarities which are discussed in light of the IWA draft uniform protocol for activated sludge modelling. The authors also discuss current modelling limitations and offer suggestions to improve the state of the art.

Efficacy of heat treatments with water and fludioxonil for postharvest control of blue and gray molds on inoculated pears and fludioxonil residues in fruit

The residue levels of fludioxonil (FLU) were determined in pear cultivars Precoce di Fiorano, Coscia, and Spadona estiva after a 2-min dip in an aqueous mixture of FLU containing 300 or 100 mg/liter of active ingredient at 20 or 50 degrees C and after 12 days at 17 degrees C and 80% relative humidity (simulated shelf life conditions). The accumulation trend of FLU residues was determined in 'Precoce di Fiorano' pears after treatments with 25, 50, 100, or 200 mg/liter of active ingredient at 20 or 50 degrees C for 2 min or at 60 degrees C for 1 min. The efficacy of heat treatments with water and FLU was investigated on artificially inoculated 'Precoce di Fiorano', 'Coscia', and 'Spadona estiva' pears for the control of postharvest blue mold and gray mold caused by Penicillium expansum and Botrytis cinerea, respectively. Treatment with 300 mg/liter FLU at 20 degrees C resulted in residue levels similar to those from treatment with 100 mg/liter FLU at 50 degrees C in 'Coscia' fruit but in significantly lower residues in 'Precoce di Fiorano' and 'Spadona estiva' pears. Post-shelf life residues decreased in all cultivars, especially in 'Spadona estiva' pears treated with 300 mg/liter FLU at 20 degrees C. Residue levels of FLU in 'Precoce di Fiorano' pears treated at 20, 50, or 60 degrees C were correlated with fungicide dosage. When an equal rate was used, treatment at 50 degrees C resulted in a higher and a notably higher FLU deposition than that found under treatment at 60 and 20 degrees C, respectively. The in vitro tests showed that both pathogens were very sensitive to FLU, with MICs averaging 0.05 and 0.1 mg/liter for B. cinerea and P. expansum isolates, respectively. The 50% effective concentration ranged between 0.01 and 0.05 mg/liter for B. cinerea and between 0.05 and 0.1 mg/liter for P. expansum. In the in vivo trials, hot water treatment effectively reduced the incidence of both diseases during the first 4 to 8 days, depending on cultivar, dip temperature, and type of inoculum. However, as the incubation time proceeded, decay reduction was generally lower and the benefit of heat treatments was notably reduced or almost lost. In contrast, all treatments with FLU had a long-lasting effect. Treatments with heated FLU were more effective than those with unheated FLU; reduced concentrations of active ingredient were required to achieve a comparable control of blue and gray mold decay in these pears.

Genetic structure of wild and cultivated olives in the central Mediterranean basin

BACKGROUND AND AIMS

Olive cultivars and their wild relatives (oleasters) represent two botanical varieties of Olea europaea subsp. europaea (respectively europaea and sylvestris). Olive cultivars have undergone human selection and their area of diffusion overlaps that of oleasters. Populations of genuine wild olives seem restricted to isolated areas of Mediterranean forests, while most other wild-looking forms of olive may include feral forms that escaped cultivation.

METHODS

The genetic structure of wild and cultivated olive tree populations was evaluated by amplified fragment length polymorphism (AFLP) markers at a microscale level in one continental and two insular Italian regions.

KEY RESULTS

The observed patterns of genetic variation were able to distinguish wild from cultivated populations and continental from insular regions. Island oleasters were highly similar to each other and were clearly distinguishable from those of continental regions. Ancient cultivated material from one island clustered with the wild plants, while the old plants from the continental region clustered with the cultivated group.

CONCLUSIONS

On the basis of these results, we can assume that olive trees have undergone a different selection/domestication process in the insular and mainland regions. The degree of differentiation between oleasters and cultivated trees on the islands suggests that all cultivars have been introduced into these regions from the outside, while the Umbrian cultivars have originated either by selection from local oleasters or by direct introduction from other regions.

Genetic structure of wild and cultivated olives in the central Mediterranean basin

BACKGROUND AND AIMS

Olive cultivars and their wild relatives (oleasters) represent two botanical varieties of Olea europaea subsp. europaea (respectively europaea and sylvestris). Olive cultivars have undergone human selection and their area of diffusion overlaps that of oleasters. Populations of genuine wild olives seem restricted to isolated areas of Mediterranean forests, while most other wild-looking forms of olive may include feral forms that escaped cultivation.

METHODS

The genetic structure of wild and cultivated olive tree populations was evaluated by amplified fragment length polymorphism (AFLP) markers at a microscale level in one continental and two insular Italian regions.

KEY RESULTS

The observed patterns of genetic variation were able to distinguish wild from cultivated populations and continental from insular regions. Island oleasters were highly similar to each other and were clearly distinguishable from those of continental regions. Ancient cultivated material from one island clustered with the wild plants, while the old plants from the continental region clustered with the cultivated group.

CONCLUSIONS

On the basis of these results, we can assume that olive trees have undergone a different selection/domestication process in the insular and mainland regions. The degree of differentiation between oleasters and cultivated trees on the islands suggests that all cultivars have been introduced into these regions from the outside, while the Umbrian cultivars have originated either by selection from local oleasters or by direct introduction from other regions.

Genetic structure of wild and cultivated olives in the central Mediterranean basin

BACKGROUND AND AIMS

Olive cultivars and their wild relatives (oleasters) represent two botanical varieties of Olea europaea subsp. europaea (respectively europaea and sylvestris). Olive cultivars have undergone human selection and their area of diffusion overlaps that of oleasters. Populations of genuine wild olives seem restricted to isolated areas of Mediterranean forests, while most other wild-looking forms of olive may include feral forms that escaped cultivation.

METHODS

The genetic structure of wild and cultivated olive tree populations was evaluated by amplified fragment length polymorphism (AFLP) markers at a microscale level in one continental and two insular Italian regions.

KEY RESULTS

The observed patterns of genetic variation were able to distinguish wild from cultivated populations and continental from insular regions. Island oleasters were highly similar to each other and were clearly distinguishable from those of continental regions. Ancient cultivated material from one island clustered with the wild plants, while the old plants from the continental region clustered with the cultivated group.

CONCLUSIONS

On the basis of these results, we can assume that olive trees have undergone a different selection/domestication process in the insular and mainland regions. The degree of differentiation between oleasters and cultivated trees on the islands suggests that all cultivars have been introduced into these regions from the outside, while the Umbrian cultivars have originated either by selection from local oleasters or by direct introduction from other regions.

[Surgical treatment of varicocele in day surgery]

Aim of this study is the comparison between spermatic vein ligature (Ivanissevich technique) and low intrafunicular ligature in the surgical treatment of varicocele. The Authors present two groups of patients (total 61) operated between 1995 and 1999 with the above-mentioned surgical techniques. Apart from the utilized method, they didn't ascertain any improvements in the spermiograms of the patients older than 30 years. The low ligature of the spermatic veins demonstrated the advantages of surgery treatment and lower percentage of relapses.

[Monomorphic adenomas of the parotid gland: description of 3 clinical cases]

Three cases of monomorphic adenomas (two oncocytic adenomas and one basal cell adenoma) of the parotid gland are reported. The diagnosis is based on echography with fine needle biopsy and cervical computerized tomography. Because of the high percentages of multicentricity, the therapy of choice is superficial parotidectomy when the lesion is in the pre-neural lobe of the gland, or total parotidectomy in case of a deep mass.

Disposition of propofol between red blood cells, plasma, brain and cerebrospinal fluid in rabbits

The disposition of propofol in the blood and brain of New Zealand rabbits was studied in three groups of six rabbits. One group received a single anaesthetic dose; a second group received a 1-h infusion; and a third group was studied after the rabbits were judged to have recovered from a 1-h infusion. There was a high concentration of propofol in the red blood cell fraction and in the brain, however, the red blood cell concentration largely exceeded the one found in the brain in all groups of animals. This is consistent with the high fat solubility of diisopropylphenol. The possible effects of propofol sequestered in red blood cells is discussed.

Early postoperative MRI findings following surgery for herniated lumbar disc. Part II: A gadolinium-enhanced study

The aim of our study was to evaluate the contrast-enhanced MR imaging (MRI) findings, in the early postoperative period, in unselected patients undergoing lumbar microdiscectomy (15/16 had total resolution of their symptoms). Contrast-enhanced imaging studies were performed, in all 16 patients of our series, before surgery, and at the third postoperative day and, two months after surgery. Postoperative paraspinal muscles enhancement was present in all patients. In the postoperative period, nerve root enhancement was present in 5/16 patients at the early survey and persisted in one after two months. A pseudohernia depicted as epidural intermediate signal intensity tissue, was seen in 13 patients at the third day MRI, and only in eight after two months. This pseudohernia enhanced peripherally in 8/13 patients and enhanced homogeneously in the remaining five at the first postsurgical examination; in the late MRI the peripheral enhancement was appreciable in only two patients while a homogeneous enhancement was observed in six. Clinical symptoms resolved completely in 14/16 patients on clinical evaluation at the third postoperative day, while the remaining two patients showed residual symptoms and signs of radicular compression. At the early MRI these two patients showed intradural nerve root enhancement. Two months later, one patient did not show the previously described nerve root enhancement and improved clinically, while the other had a positive Straight Leg Raising Sign with persistent intradural nerve root enhancement. In conclusion, no correlation between clinical course and contrast-enhancement of pseudohernia and extradural nerve root was appreciable, although intradural nerve root enhancement seems to represent a clinically relevant finding.

[Echographic measurements in the posterior cranial fossa: the normal values of the term and premature newborn infant]

INTRODUCTION

We support the normal standards for two sonographic (US) signs of the posterior cranial fossa, namely the magnitude of the cisterna magna and the height of the fourth ventricle fastigium, in preterm and fullterm infants.

MATERIALS AND METHODS

The cisterna magna was measured as the distance between the inferior aspect of the cerebella vermis and the inner aspect of the occiput. The height of the fourth ventricle fastigium was calculated as the line drawn from the fastigium to the inner aspect of the occiput, close to the opisthion.

RESULTS

The cisterna magna was .46 +/- .13 cm in preterm infants and .45 +/- .1 cm in fullterm infants (the difference was not significant), whereas the height of the fourth ventricle fastigium was 1.7 +/- .26 cm in preterm and 1.9 +/- .16 cm in fullterm infants (the difference was significant, p < .005).

CONCLUSIONS

The finding of a cisterna magna of equal size in preterm and fullterm infants is in agreement with the concept that subarachnoid and cisternal spaces of the posterior fossa are still large at birth and start to decrease in size later in life. Our results suggest that a cisterna magna smaller than .2 cm in height and/or a fastigium closer than 1.2 cm to the basiocciput in preterm and closer than 1.6 cm in fullterm infants indicate, in a proper clinical context, an abnormally low cerebellum position (Arnold-Chiari malformation). On the other hand, cisterna magna values exceeding .72 in preterm and .65 cm in fullterm infants, as well as fastigium values exceeding 2.22 cm in both groups may suggest the presence of the Dandy-Walker complex or of an arachnoid cyst.

Early postoperative MRI findings following surgery for herniated lumbar disc

MRI is routinely used in the evaluation and management of patients with failed back surgery syndrome (FBSS). However, its value is unclear in the early detection of signs that can negatively affect that later course of surgical cases. The purpose of the present study is to describe the MR images of early postoperative MRI at 3 days in 30 unselected patients who underwent lumbar microdiscectomy, and to correlate the findings with follow up MRI at 8 weeks and with final outcome. The findings are correlated with literature data. Early postoperative MRI findings were consisting of pseudohernia in 24 patients (80%), annular rent in 23 patients (80%), and other non-specific postoperative findings. On the late MRI the pseudohernia persisted in 12 patients (50%), the annular rent in 4 patients (15%) and asymptomatic pseudo-spondylodiscitis was apparent in 3 patients (10%) as was a case of true spondylodiscitis. Therefore, early postoperative findings have limited value in the management of patients after surgery for lumbar disc herniation, since the images were not correlated with the immediate clinical course after surgery nor with the late radiological and clinical outcome. The evident imaging changes in the early postoperative period after lumbar disc surgery limit the accuracy of the interpretation of MRI examinations.

[Study of prostatic carcinoma with ultrasonography and magnetic resonance with "dedicated" surface coil]

We investigated the role of an experimental surface coil for low field (0.2 T) MRI of prostatic gland carcinoma; the study was performed comparing MRI with US findings and with bioptic and pathologic results. To this purpose, 16 patients with prostatic cancer suspected at US and demonstrated with US-guided biopsy, were examined with low intensity field (0.2 T) MRI performed with a dedicated saddle-shaped coil and a body coil. This experimental surface coil with perineal application is used to study the prostatic gland with low field MR equipment where no transrectal probe is available. We analyzed the results of this study and found that, in all patients but one, the neoplastic lesions exhibited low signal intensity on T2-weighted images, while the normal gland was hyperintense. Six patients underwent radical prostatectomy and diagnostic imaging findings were correlated with pathologic findings obtained with whole mount specimens and serial histologic slides. The number of tumor foci, their site and size, and stromal reaction were studied on T2-weighted images; the typical low signal intensity was absent in one of 16 patients, in which case the microscopic exam of pathologic specimens showed extensive tumor spread with infiltration of perineural lymphatic vessels, with neither nodular patterns nor stromal reactions. The correlation between MR findings and the whole mount specimens (n = 6) demonstrated MR underestimation of tumor spread. In our opinion, this technique is useful for the detection and characterization of prostatic lesions, in spite of the presence of isointense lesions and the risk of underestimating the disease, especially to the prostatic capsule. To conclude, the dedicated surface coil can improve the diagnostic accuracy of low field MRI.

`Fortune' Mandarin Quality following Prestorage Water Dips and Intermittent Warming during Cold Storage

Freshly harvested `Fortune' mandarins (Citrus reticulata Blanco) were dipped for 3 minutes in 25 or 52C water and then stored for 5 weeks at 2C. Then, the fruit were or were not intermittently warmed at 10C for 3 days after each 4-day storage period. All fruit then were held at 20C for 1 week to simulate retail marketing. Chilling injury was more severe in fruit dipped in 25C water and stored at 2C than in fruit dipped in 25C water and stored under intermittent warming. The hot dip treatment significantly reduced the extent of damage during storage and the subsequent 1 week of holding at 20C. The hot dip treatment reduced the incidence of fungal decay, especially during holding at 20C. Dip temperature and storage conditions slightly affected fruit physiological and quality characteristics. We conclude that prestorage hot dip treatments can be used to improve `Fortune' mandarin storing qualities. Also, this practice may be combined with intermittent warming during cold storage, and it could help limit fungicide use in postharvest treatments.

Propofol anticonvulsant activity in experimental epileptic status

We have examined the anticonvulsant properties of propofol in high doses in two experimental models of status epilepticus: generalized pentylenetetrazol (PTZ)-induced seizures and partial, cortically applied penicillin G-induced seizures. Propofol was administered either as a single bolus injection or as a bolus injection followed by an infusion for 1 h. When administered as a single bolus injection, propofol 12 mg kg-1 suppressed electrical and clinical seizures in PTZ generalized epileptic status, and an infusion of 50 mg kg-1 h-1 prevented the reappearance of electrical and clinical signs. In focal epileptic status, the single dose stopped paroxysmal activity and the associated clonic jerks for a few seconds. When the bolus dose was followed by an infusion, the firing bursts were replaced by isolated spikes, and contralateral jerks became sporadic and feeble. The greater efficacy of propofol against PTZ convulsions may be a reflection of the opposite action of the two drugs on neural membrane conductance: PTZ induces paroxysmal neural discharge by enhancing membrane conductance while propofol appears to decrease membrane conductance, thus suppressing paroxysmal discharge. There was no close relationship between blood concentration of the anaesthetic and its clinical effects, at least after a short-term infusion, as used in the present experiments. We suggest that propofol may be a potentially useful drug in status epilepticus in patients in whom benzodiazepines, barbiturates and phenytoin have failed.

Effect of discrete kainic acid-induced lesions of corpus caudatus and globus pallidus on glutamic acid decarboxylase of rat substantia nigra

Locally applied kainic acid was used in order to destroy pallidal perikarya without damaging axons en passage, in an effort to clarify the role of the globus pallidus as a source of nigral GABAergic terminals. Rats were microinjected unilaterally with kainic acid in the globus pallidus, head, body and tail of the caudate and were sacrificed 7 days later. The forebrain of each rat was examined histologically in order to establish the extent of the lesion and nigral glutamate decarboxylase (GAD) was assayed as a marker of GABAergic terminals. Kainic acid produced in the globus pallidus loss of neuronal perikarya and reactive gliosis. Large multipolar neurons of the globus pallidus were characteristically absent on the lesioned-side. Lesions of the pallidum resulted in a non-significant (5.5%) reduction of nigral GAD. Kainate lesions restricted to the head of the caudate resulted in a significant (19%) drop of nigral GAD, while lesions of the caudate body provided the largest reductions of nigral GAD (53%). Lesions of the caudate tail were without effect. The results indicate that nigral GAD arises mostly from the body and, in part, also from the head of the caudate but not from the globus pallidus or from the tail of the caudate.