Needle Tissue Research Articles

Variation of mobile carbon reserves in trees at the alpine treeline ecotone is under environmental control

In low temperature-adapted plants, including treeline trees, light-saturated photosynthesis is considerably less sensitive to temperature than growth. As a consequence, all plants tested so far show increased nonstructural carbohydrate (NSC) tissue concentrations when exposed to low temperatures. Reduced carbon supply is thus an unlikely cause for low temperature range limits of plants. For altitudinal treeline trees there is, however, a possibility that high NSC genotypes have been selected. Here, we explored this possibility using afforestations with single-provenance conifers along elevational gradients in the Southern Chilean Andes and the Swiss Alps. Tree growth was measured at each of four approximately equidistant elevations at and below the treeline. Additionally, at the same elevations, needle, branch and stem sapwood tissues were collected to determine NSC concentrations. Overall, growth decreased and NSC concentrations increased with elevation. Along with previous empirical and experimental studies, the findings of this study provide no indication of NSC reduction at the treeline; NSC increased in most species (each represented by one common population) towards their upper climatic limit. The disparity between carbon acquisition and structural carbon investment at low temperature (accumulation of NSC) thus does occur even among genotypes not adapted to treeline environments.

SU-D-213AB-06: Surface Texture and Insertion Speed Effect on Needle Friction.

High frictional forces between the needle surface and tissue cause tissue deflection which hinders accurate needle placement for procedures such as brachytherapy and needle biopsy. Accurate needle placement isimportant to maximize procedure efficacy. This work investigates how needle surface roughness and insertion speed affect the frictional forcebetween a needle and tissue. A friction experiment was conducted to measure the force of friction between bovine liver and three 11 gauge needles having Ra surface roughness of 3.43, 1.33, and 0.2 μm. Each of the three needles were mounted on a linear slide and were advanced and retracted through bovine liver at speeds of 50, 100, 150, and 200 mm/s for a total of 12 trials. In each trial the needle was advanced and retracted in 10 cycles producing a steady state insertion force and a steady state retraction force for each cycle. A force sensor connecting the needle to the linear slide recorded the resistance force of the needle sliding through the liver. The liver was mounted in a box with a pneumatic cylinder which compressed the liver sample by 11.65 kPa. The roughest needle (Ra = 3.43 μm) on average produced 68, 73, 74, and 73% lower friction force than the smoothest needle (Ra = 0.2 μm) for the speeds of 50, 100, 150, and 200mm/s, respectively. The second roughest needle (Ra = 1.33 μm) on average produced 25, 45, 60 and 64% lower friction force than the smoothest needle (Ra = 0.2 μm) for the speeds of 50, 100, 150, and 200 mm/s, respectively. Rougher needle surface texture and higher insertion speed reduced frictional forces between the tissue and the needle. Future studies will examine how frictional forces can be modeled and predicted given surface texture and insertion speed.

Isolation and characterization of pathogen defence‐related class I chitinase from the actinorhizal tree Casuarina equisetifolia

SummaryCasuarina equisetifolia has the widest distribution of all Casuarina species and is a nitrogen‐fixing tree of considerable social, economic and environmental importance. Trichosporium vesiculosum, a causal agent of blister bark disease, is a serious pathogen of C. equisetifolia. In this study, a cDNA clone encoding class I chitinase (CeChi1) belonging to PR‐3 family was cloned and characterized from the needle tissues of C. equisetifolia challenged with the toxic exudate of the fungal pathogen T. vesiculosum. The CeChi1 open reading frame comprised 966 nucleotides that encoded 321 amino acid residues with the molecular mass of mature protein being approximately 34 kDa. Analysis of the predicted amino acid sequence revealed the similarity of CeChi1 protein to class I chitinase from other plant species containing a hydrophobic signal peptide domain and hinge domain. The sequence also harboured a cysteine‐rich chitin‐binding domain and lysozyme‐like domain. A hydrophobic C‐terminal domain similar to the vacuole targeting sequences of class I chitinases isolated from other plants was also detected. The genomic sequence of CeChi1 indicated that the coding region contained three exons and two introns. In silico analysis of the untranslated regions revealed the presence of several cis‐acting regulatory elements associated with hormonal regulation and stress responses. Quantitative real‐time PCR analyses at different time points showed upregulation of the transcript during pathogen elicitation and salicylic acid signalling. However, no significant expression of CeChi1 was observed during other abiotic stress condition including wounding, water deficit, salt and heat stress revealing the specific expression of the gene during pathogenesis. This is the first report on isolation of a gene from C. equisetifolia, and the detailed functional analyses of CeChi1 will help in understanding its specific role in defence against pathogens in this tropical tree species.

Isolation and identification of diazotrophic bacteria from internal tissues ofPinus contortaandThuja plicata

Lodgepole pine ( Pinus contorta var. latifolia Engelm. ex S. Watson) and western red cedar ( Thuja plicata Donn ex D. Don) are capable of growing in soils that are severely nitrogen-limited. A rarely evaluated but possible nitrogen source for gymnosperms growing at nutrient poor sites is nitrogen fixation by endophytic bacteria. To investigate this possibility, we looked for nitrogen-fixing bacteria in surface-sterilized needle, stem, and root tissues of naturally regenerating lodgepole pine and western red cedar seedlings (2–4 years old) and trees (>20 years old) growing near Williams Lake, Chilliwack Lake, and Boston Bar, British Columbia, Canada. Ninety-nine bacterial isolates were obtained by plating surface-sterilized plant tissue extracts on tryptic soy agar (TSA) and combined carbon medium agar (CCMA), a nitrogen-free medium. Bacterial isolates were identified using gas chromatographic fatty acid methyl ester (GC-FAME) and 16S rRNA gene analyses and were evaluated for nitrogenase activity using an acetylene reduction assay. Representatives of the genera Bacillus and Paenibacillus dominated the culturable endophytic bacterial community in tissues of both tree species, with three Paenibacillus isolates and one Dyadobacter fermentans strain demonstrating consistently high acetylene-reduction activities. Our results raise the possibility that endophytic nitrogen fixation provides a supplementary nitrogen source for naturally regenerated lodgepole pine and western red cedar.

Seasonal dynamics of histological parameters of the needles of Scots pine (Pinus sylvestris L.) growing in conditions of excess ammonia

Ammonia is one of the most important aerial pollutants which might affect morphology of conifers. The purpose of our study was to assess morphological and histological parameters of the needles of Scots pine (Pinus sylvestris L.) growing under elevated concentration (up to 17.5 μg m–3) ammonia (near JSC Achema, Lithuania) during the vegetation season (June–August, 2009). Current-year needles from the young age stand with higher concentration of air ammonia (17.5 μg m–3) were wider (p < 0.05; 1.11 times) when compared to the needles of Kačerginė site (3.9 μg m–3). The investigation of the seasonal dynamics of the needle morphology (length, width, thickness) and the thickness of the needle tissues in the cross-section (epidermis, hypodermis, mesophyll and central cylinder tissues – transfusion parenchyma and sclerenchyma) in most other cases did not reveal statistically significant differences between the trees growing in ammonia-polluted and relatively clean sites. It was true for both middle-aged and young age stands. Under the elevated concentration of air-ammonia, only some tendencies were observed for thicker needles (up to 1.05 times), thicker adaxial mesophyll (up to 1.10 times) and adaxial transfusion parenchyma (up to 1.06 times) of the needles. For middle-aged stands significant (p < 0.01) needle age differences were observed according to the abaxial and adaxial mesophyll thickness (up to 1.21 times thicker in 1-year-old needles), the same was true for the needles of the young age stand (up to 1.25 times). At the end of August, the average length of 1-year-old needles was 76 mm, width 1.7 mm and thickness 0.76 mm. For some histological parameters statistically significant (p < 0.05) seasonal differences were observed: the thickness of adaxial transfusion parenchyma was decreasing and the sclerenchyma width was increasing within the June–August period.

A Novel Force Modeling Scheme for Needle Insertion Using Multiple Kalman Filters

In this paper, the interaction force between a surgical needle and soft tissue is studied. The force is modeled using a novel nonlinear dynamic model. Encouraged by the LuGre model for representing friction forces, the proposed model captures all stages of needle-tissue interaction, including puncture, cutting, and friction forces. An estimation algorithm for identifying the parameters of the model is presented. This online approach, which is based on sequential extended Kalman filtering, enables us to characterize the total contact force using an efficient mathematical model. The algorithm compares the axial force measured at the needle base with its expected value and then adapts the model parameters to represent the actual interaction force. While the nature of this problem is very complex, the use of multiple Kalman filters makes the system highly adaptable for capturing the force evolution during an interventional procedure in standard operating conditions. To evaluate the performance of our model, experiments were performed on artificial phantoms.

Development and evaluation of an epidural injection simulator with force feedback for medical training.

Performing epidural injections is a complex task that demands a high level of skill and precision from the physician, since an improperly performed procedure can result in serious complications for the patient. The objective of our project is to create an epidural injection simulator for medical training and education that provides the user with realistic feel encountered during an actual procedure. We have used a Phantom haptic interface by SensAble Technologies, which is capable of three-dimensional force feedback, to simulate interactions between the needle and bones or tissues. An additional degree-of-freedom through an actual syringe was incorporated to simulate the "loss of resistance" effect, commonly considered to be the most reliable method for identifying the epidural space during an injection procedure. The simulator also includes a new training feature called "Haptic Guidance" that allows the user to follow a previously recorded expert procedure and feel the encountered forces. Evaluations of the simulator by experienced professionals indicate that the simulation system has considerable potential to become a useful aid in medical training.

Frictional Force Modeling Ranging from Hyper to Slow Relative Velocity between a Needle and Liver Tissue

Frictional Force Modeling Ranging from Hyper to Slow Relative Velocity between a Needle and Liver Tissue

Fungi colonizing shoots of common yew (Taxus baccata L.) in the Jagiellonian University Botanic Garden in Cracow

The aim of the investigations was determination the reasons of dying down of needles and branches of common yew (&lt;i&gt;Taxus baccata&lt;/i&gt; L.) in the park collection of Botanic Garden of Jagiellonian University in Cracow. The disease changes of infectious nature were observed on the examined plants' parts. The changes'appearance, its location and extent were described in details. At first the spots were brown colour with distinct hem. Then the needle and branch tissues were dying down. From end of May to July mass falling down of infesteted needles was observed. Mycological analysis of diseased tissues showed 34 fungi species. To the dominant species belonged: &lt;i&gt;Alternaria alternata&lt;/i&gt;, &lt;i&gt;Colletotrichum gloeosporioides&lt;/i&gt;, &lt;i&gt;Fusarium&lt;/i&gt; spp., &lt;i&gt;Pestalotiopsis guepinii&lt;/i&gt;, &lt;i&gt;Phomopsis juniperivora&lt;/i&gt; and &lt;i&gt;Zythiostroma pinastri&lt;/i&gt;. Common yew pathogens: &lt;i&gt;Phomopsis juniperivora&lt;/i&gt; and &lt;i&gt;Sclerophoma pityophila&lt;/i&gt; were found among the isolated fungi.

Immunocytochemistry versus nucleic acid amplification in fine needle aspirates and tissues of extrapulmonary tuberculosis

Background:Immunocytochemistry (ICC) is an established routine diagnostic adjunct to cytology and histology for tumor diagnosis but has received little attention for diagnosis of tuberculosis.Aims:To have an objective method of direct visualization of mycobacteria or their products in clinical extrapulmonary tuberculosis (EPTB) specimens, immunocytochemical localization of M. tuberculosis antigen by staining with species specific monoclonal antibody to 38-kDa antigen of Mycobacterium tuberculosis complex.Materials and Methods:Immunostaining with specific monoclonal antibody to 38-kDa antigen of Mycobacterium tuberculosis complex was done in fresh and archival fine needle aspirates and tissue granulomata of 302 cases of extrapulmonary tuberculosis and was compared with the molecular diagnostic i.e., nucleic amplification and conventional [Cytomorphology, Ziehl Neelsen (ZN) staining and culture] tests and 386 controls.Results:Diagnostic indices by Bayesian analysis for all types of archival and fresh material varied from 64 to 76% in nucleic acid amplification (NAA) and 96 to 98% in ICC. There was no significant difference in the diagnostic indices of ZN staining and/ or ICC in fresh or archival material whereas the sensitivity of NAA differed significantly in fresh versus archival material both in cytology (71.4% vs 52.1%) and histology (51.1% vs 38.8%). ICC can be easily used on archival smears and formalin-fixed paraffin-embedded tissue sections with almost equal sensitivity and specificity as with fresh material, in contrast to NAA which showed significant difference in test results on archival and fresh material.Conclusions:Low detection sensitivity of MTB DNA in archival material from known tuberculous cases showed the limitation of in-house NAA-based molecular diagnosis. ICC was found to be sensitive, specific and a better technique than NAA and can be used as an adjunct to conventional morphology and ZN staining for the diagnosis of EPTB in tissue granulomas.

Study on Extraction of Shikimic Acid from Pine Needles of Pinus Elliottii Engelm by Means of Microwave Pretreatment

The aim was to provide scientific basis for development and utilization of pinus elliottii engelm resources.As the raw material, pines needles of pinus elliottii were moistened first by vaporization medium. After that, the needles were processed in advance by microwave to change tissues of needles, and finally, the Shikimic acid was extracted from the needles in hot water. Meanwhile, the extraction method is compared with traditional one in the paper. As a result, the perfect technological conditions were gained for extraction of Shikimic acid by microwave preprocessing. The method is: moistening pine needles within 15 minutes in 70% ethanol water which was 1.6 times weight of needles, then, processing the needles for 60 seconds by 70W microwave. The processing time should increase 30 seconds every 5-gram material added. Finally, the extraction lasted over 30 minutes adding 25-time hot water at 80°C. Seven eighths of extraction time by microwave preprocessing is shortened compared by the traditional extraction method, and extraction ratio for Shikimic acid raises by 35.8%.

Study on Extraction of Shikimic Acid from Pine Needles of Pinus Elliottii Engelm by Means of Microwave Pretreatment

The aim was to provide scientific basis for development and utilization of pinus elliottii engelm resources.As the raw material, pines needles of pinus elliottii were moistened first by vaporization medium. After that, the needles were processed in advance by microwave to change tissues of needles, and finally, the Shikimic acid was extracted from the needles in hot water. Meanwhile, the extraction method is compared with traditional one in the paper. As a result, the perfect technological conditions were gained for extraction of Shikimic acid by microwave preprocessing. The method is: moistening pine needles within 15 minutes in 70% ethanol water which was 1.6 times weight of needles, then, processing the needles for 60 seconds by 70W microwave. The processing time should increase 30 seconds every 5-gram material added. Finally, the extraction lasted over 30 minutes adding 25-time hot water at 80°C. Seven eighths of extraction time by microwave preprocessing is shortened compared by the traditional extraction method, and extraction ratio for Shikimic acid raises by 35.8%.

Variation in telomeric repeats of Scots pine (Pinus sylvestris L.)

The shortening of telomeres, the specific structures at the end of the eukaryotic chromosomes, has been associated with ageing and loss of cell replication or regeneration capacity. The aim of this study was to determine the variation in telomeric repeats during the life-span of Scots pine (Pinus sylvestris L.) by studying different tissues and age groups ranging from immature embryos to cambium, buds, and needles of mature, 200-year-old trees. The telomeric repeats in Scots pine including interstitial and centromeric repeats ranged from 0.9 up to 25 kb, and true telomeres were evaluated to have a mean length of 19.3 kb (±SE 0.17). Telomeres were observed to shorten with increasing tissue differentiation, embryonal samples having the longest repeats with an average length of 21.1 (±0.34) to 21.7 kb (±0.42) and the needles having, on average, the shortest repeats of 18.1 kb (±0.24). After germination, ageing per se had no significant effect on the length of telomeric repeats in cambium, bud, or needle tissues. In the older trees (50–200 years of age), the telomeres in stem cambium showed shortening towards the tree top. This is the first observation on such a position-related variation in telomeric repeats. Finally, there was a remarkable genotypic variation in the length of telomeric repeats, and this was consistent over the tissue types. In the small number of tested donor trees, the genotypic differences were not related to regeneration ability in tissue culture.

Effect of Water Stress and Fungal Inoculation on Monoterpene Emission from an Historical and a New Pine Host of the Mountain Pine Beetle

The mountain pine beetle (Dendroctonus ponderosae, MPB) has killed millions of lodgepole pine (Pinus contorta) trees in Western Canada, and recent range expansion has resulted in attack of jack pine (Pinus banksiana) in Alberta. Establishment of MPB in the Boreal forest will require use of jack pine under a suite of environmental conditions different from those it typically encounters in its native range. Lodgepole and jack pine seedlings were grown under controlled environment conditions and subjected to either water deficit or well watered conditions and inoculated with Grosmannia clavigera, a MPB fungal associate. Soil water content, photosynthesis, stomatal conductance, and emission of volatile organic compounds (VOCs) were monitored over the duration of the six-week study. Monoterpene content of bark and needle tissue was measured at the end of the experiment. β-Phellandrene, the major monoterpene in lodgepole pine, was almost completely lacking in the volatile emission profile of jack pine. The major compound in jack pine was α-pinene. The emission of both compounds was positively correlated with stomatal conductance. 3-Carene was emitted at a high concentration from jack pine seedlings, which is in contrast to monoterpene profiles of jack pine from more southern and eastern parts of its range. Fungal inoculation caused a significant increase in total monoterpene emission in water deficit lodgepole pine seedlings right after its application. By 4weeks into the experiment, water deficit seedlings of both species released significantly lower levels of total monoterpenes than well watered seedlings. Needle tissue contained lower total monoterpene content than bark. Generally, monoterpene tissue content increased over time independent from any treatment. The results suggest that monoterpenes that play a role in pine-MPB interactions differ between lodgepole and jack pine, and also that they are affected by water availability.

Mo1423 Endoscopic Ultrasound-Guided Fine Needle Tissue Acquisition (EUS-FNTA) Using a 19-Gauge Needle for Histological Grading of Pancreatic Endocrine Tumors (PETs): A Prospective Study

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is increasingly used in the diagnosis of pancreatic endocrine tumors(PETs). Determination of Ki-67 expression, an important prognostic factor to grade PETs according to the WHO classification is difficult to be determined on cytological specimens. We prospectively evaluated the feasibility and yield of EUS-guided fine needle tissue acquisition (EUS-FNTA) utilizing a 19-gauge needle to obtain tissue samples for histological diagnosis and Ki-67 expression in patients with suspected PETs.

938 NEEDLE STEERING SYSTEM USING DUTY-CYCLED ROTATION FOR PERCUTANEOUS KIDNEY ACCESS

You have accessJournal of UrologyTechnology & Instruments: Robotics/Laparoscopy1 Apr 2011938 NEEDLE STEERING SYSTEM USING DUTY-CYCLED ROTATION FOR PERCUTANEOUS KIDNEY ACCESS Khaled Shahrour, Michael Ost, Nathan Wood, Stephen Jackman, Timothy Averch, and Cameron Riviere Khaled ShahrourKhaled Shahrour Pittsburgh, PA More articles by this author , Michael OstMichael Ost Pittsburgh, PA More articles by this author , Nathan WoodNathan Wood Pittsburgh, PA More articles by this author , Stephen JackmanStephen Jackman Pittsburgh, PA More articles by this author , Timothy AverchTimothy Averch Pittsburgh, PA More articles by this author , and Cameron RiviereCameron Riviere Pittsburgh, PA More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.856AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES A novel technique of percutaneous renal access (PRA) is needed to overcome the drawbacks of using rigid needles. If a flexible needle with a beveled tip is inserted into tissue, it will bend in the direction of the tip. The curve depends on the needle flexibility and tissue resistance. If the needle spins constantly during insertion, it follows a straight path as the bevel is negated. Alternating periods of spinning and stopping (duty-cycling) allows for proportional control of the trajectory in order to steer the needle in tissue non-traumatically. Our objective is to test the ability of the duty-cycled steerable needle system to follow a specific trajectory in vitro using phantom and swine kidneys. METHODS The nitinol needle has a 0.52mm diameter with a 7° bevel and is attached to a motor for inserting motion and to another motor for spinning. The system is controlled using a graphical user interface to automatically select tip orientation, insertion and spinning speeds based on the actual needle position. A PRA phantom kidney training model was used in which the minor calyces were set as target points and needle is followed in real-time by a camera. In swine experiments, needle is followed fluoroscopically into the contrast-filled calyces. The distance between the actual path of the needle and the planned path (cross track error) and the final needle position were the objective and subjective outcomes respectively. RESULTS The needle successfully entered the phantom and swine kidneys during all attempts. Mean cross track error was 0.71mm with a range between 0.05mm and 1.4mm in phantoms. In swine kidneys, the mean cross track error was 1.38 mm. CONCLUSIONS Duty-cycled needle can be successfully steered along a pre-planed path in vitro and in swine kidney. Further studies on cadaveric and live animals are warranted prior to clinical investigation. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e376 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Khaled Shahrour Pittsburgh, PA More articles by this author Michael Ost Pittsburgh, PA More articles by this author Nathan Wood Pittsburgh, PA More articles by this author Stephen Jackman Pittsburgh, PA More articles by this author Timothy Averch Pittsburgh, PA More articles by this author Cameron Riviere Pittsburgh, PA More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Hollow needle tissue insertion force model

In this study, a mechanistic approach using elementary cutting tool (ECT) edges of varying inclination and normal rake angles is demonstrated to be capable to predict hollow needle insertion force. A needle force model is developed and validated for the specific case of 11 gauge two-plane symmetric needles. Blades of varying inclination and rake angles are inserted into bovine liver to determine the specific force of initial tissue cutting for the given edge geometry; this information is applied to the ECT force model which is validated against experimental force results of hollow needles inserted into bovine liver.

Antioxidant response of overwintering conifers suggest species specific strategies for coping with excess excitation energy

Abstract Background/Question/Methods: Evergreen plants, growing in seasonally cold environments, must cope with a severe imbalance between light absorption and its utilization, as low temperatures during winter inhibit photosynthetic carbon reduction. In such conditions photoprotective mechanisms are critical, including the leaf antioxidant systems of plants. In a previous study examining Taxus cuspidata, we found significant increases in the enzyme glutathione reductase (GR) and the metabolite glutathione (GSH) during winter, but no increases in the enzymes superoxide dismutase, ascorbate peroxidase (APX) or the metabolite ascorbate (ASC). These results led to the hypothesis that GR and GSH serve an important role during winter stress that was separate form their role in the ascorbate glutathione cycle. The goal of this study was to examine the seasonal response of several species of conifers in order to determine if the differences in the antioxidant response observed in Taxus would occur generally in conifers during winter, or if there are species specific effects. We collected needle tissue in summer and winter from three conifer species: eastern white pine (Pinus strobus L.), balsam fir [Abies balsamea (L.) P. Mill], and white cedar (Thuga occidentalis L.). We analyzed the activity of both GR and APX and the amount of GSH and ASC. Results/Conclusions: Our results demonstrated significant increases in the antioxidant enzyme GR in all species in response to winter stress. The antioxidant enzyme APX showed significant winter increases in two species (pine and cedar) but not the third (fir). Preliminary results of the antioxidant metabolites glutathione and ascorbate show similar results. Our data suggest that the different species examined utilize different strategies for coping with excess excitation energy during winter. Pine and cedar apparently boost their overall antioxidant enzyme capacity and their utilization of the ascorbate glutathione cycle. Balsam fir shows a similar response to Taxus cuspidata, where glutathione reductase activity is significantly increased but ascorbate peroxidase activity is not. These results suggest a role for reduced glutathione in winter-stressed fir that is independent of its role in the ascorbate glutathione cycle.

State of Scots pine (Pinus sylvestris L.) under nutrient and water deficit on coastal dunes of the Baltic Sea

The aim of the present study was to assess the ecophysiological state of Scots pine (Pinus sylvestris L.) growing at different heights on one of the typical coastal sand dunes in the dune field situated in southwestern Estonia. Dependence of the anatomical structure, morphological parameters, nutrients accumulation and biochemical characteristics of needles on the location of the site on the dune and on the concentration of nutrients in soil and in needle tissues was established. Correlation analysis revealed the dependence of chlorophyll a on the concentration of N and Mg in soil as well as in needles. The mesophyll area and chlorophyll concentration in needles were smallest on the top of the dune. The proportion of epidermis in the total needle cross-section area from the top was a little larger than in the needles from the bottom; the epicuticular wax layer on needles decreased towards the top. The length of needles and shoots was the lowest on the top of the dune, where the growth substrate contains notably less nutrients and water than needed for optimum growth of trees. The t test showed statistically significant larger average tree-ring width of the pines growing at the bottom. The pines on the top and at the bottom of the dune were not sensitive to temperature conditions. The radial growth of pines on the top of the dune was positively correlated with the total precipitation of the previous year.

MicroRNAs, the epigenetic memory and climatic adaptation in Norway spruce

*Norway spruce expresses a temperature-dependent epigenetic memory from the time of embryo development, which thereafter influences the timing bud phenology. MicroRNAs (miRNAs)are endogenous small RNAs, exerting epigenetic gene regulatory impacts. We have tested for their presence and differential expression. *We prepared concatemerized small RNA libraries from seedlings of two full-sib families, originated from seeds developed in a cold and warm environment. One family expressed distinct epigenetic effects while the other not. We used available plant miRNA query sequences to search for conserved miRNAs and from the sequencing we found novel ones; the miRNAs were monitored using relative real time-PCR. *Sequencing identified 24 novel and four conserved miRNAs. Further screening of the conserved miRNAs confirmed the presence of 16 additional miRNAs. Most of the miRNAs were targeted to unknown genes. The expression of seven conserved and nine novel miRNAs showed significant differences in transcript levels in the full-sib family showing distinct epigenetic difference in bud set, but not in the nonresponding full-sib family. Putative miRNA targets were studied. *Norway spruce contains a set of conserved miRNAs as well as a large proportion of novel nonconserved miRNAs. The differentially expression of specific miRNAs indicate their putative participation in the epigenetic regulation.