Length Of Cones Research Articles

СОСТОЯНИЕ ЖЕНСКОЙ ГЕНЕРАТИВНОЙ СФЕРЫ СОСНЫ ОБЫКНОВЕННОЙ В ДЕЙСТВУЮЩЕМ ОЧАГЕ КОРНЕВОЙ ГУБКИ (HETEROBASIDION ANNOSUM (FR.) BREF.)

Evaluation of the manifestation of Scots pine trees reaction to the weakening effect of Heterobasidion annosum (Fr.) Bref. is relevant from the perspective of the potential opportunities for further natural regeneration of the forest. The main reason for the decrease in the biological stability of the pine plantation was the development of the root sponge focus. Over the three-year period 2017-2019 the weighted average tree health category in the sample area increased from 2.21 to 2.52. The morphometric parameters of cones turned out to be more stable in the female generative sphere. Greater variability was noted for full-grain seed yield and the number of sterile apex scales. Relatively high preservation of seed ovules was found in the first and second vegetative periods of development within the boundaries of average values. For trees of different status categories during the whole period of observations it was 70.60-81.77 and 79.07-88.35% respectively, which indicated sufficient quality of pollination and marked compatibility of male and female genotypes against the background of reduced viability of mother trees. Embryo survival in the experiment reached 63.44-81.48%. The sensitivity of the generative sphere of Scots pine to the stress caused by the development of the disease has been proved. A significant decrease in the average length and diameter of mature cones and a relative increase in female reproduction rates were confirmed with the weakening and dying out of pine trees infected with root sponge. The possibility of identifying separate periods of preservation of ovules during gametophytic and embryonic cycles and the annual regularity of seed production allow us to recommend Scots pine for monitoring the state of the female generative sphere and assess the potential of the species to survive the action of aggressive stressors, such as Heterobasidion annosum (Fr.) Bref.

Изменчивость морфоструктурных показателей разных возрастных поколений в популяциях сосны (Pinus sylvestris L.) в условиях постоянного избыточного увлажнения почв северной тайги Архангельской области

The data is presented for studying the variability of morphostructural parameters of different age (g1 and g2) pine populations under conditions of constant excessive soil moisture of the northern taiga of the Arkhangelsk region. The frequency of occurrence distribution of the age and morphostructural parameters (size of the trunk and crown, self-pruning, length of coarse bark, size and number of side shoots, length and life span of needles) of trees is shown. It has been established that pine trees with smaller trunk and crown sizes, worse self-pruning are more common. Greater height and diameter of the trunk, length and diameter of the crown, better self-pruning, a greater length of the coarse bark is observed in the older generation (g2). This is due to the older age of the trees. It has been established that the relationship between the height of the trunk and the age of the trees is higher in the samples of young generative trees. It was revealed that the young generation (g1) has a significantly greater length and mass of cones, the length, width and height of the apophysis of seed scales compared to the older generation (g2).

INDIVIDUAL VARIABILITY OF SIBERIAN SPRUCE CONES AND SEEDS IN THE MIDDLE REACHES OF THE SEVERNAYA SOSVA RIVER (KHANTY-MANSI AUTONOMOUS OKRUG)

Individual (intrapopulation) variability of cones and seeds of Siberian spruce in the north-west of the Khanty-Mansi Autonomous Okrug in the middle reaches of the Severnaya Sosva River corresponds to "typical" values for the species in a number of traits. At the same time, increased values of the weight of 100 full seeds were noted: 0.547 (0.445-0.644) g and the number of cotyledons associated with it (6.9-8.0 pcs). The coefficient of variation of the first trait is 10 %, the second - about 4 %. The average length of cones on different trees is in the range of 49-80 mm. Seed germination and especially germination readiness have an increased variability. The duration of the seed germination period is on average 11 days, the coefficient of variation is about 12 %; it is 2-4 times less than the coefficient of variation of seed germination and germination readiness. The mass of 100 seeds is associated with the length of cones and the number of cotyledons by a reliable correlation of the average level. A closer relationship (the correlation coefficient is 0.55-0.77) was found between the germination readiness and seed germination. The results of the study contain new information about the regional biological features of Siberian spruce and may be of interest to forestry.

DIVERSITY AND PHENOTYPIC STRUCTURE OF POPULATIONS OF EUROPEAN SPRUCE (PICEA ABIES) IN THE EAST OF THE RANGE

European spruce ( Picea abies (L.) Karst.) is widespread in Europe. It is of interest to study its biological characteristics in the eastern part of the range, where it transforms into an intermediate form with Siberian spruce. Phenotypic traits of spruce in this area have so far been studied mainly by visual and descriptive techniques. The aim of the study is to study the variability of the main systematic characters, diversity and phenotypic structure of European spruce in the east of the range using mathematical and statistical techniques. This approach made it possible to objectively assess the parameters of its systematic characters, their relationship, and also to identify three significantly different groups of populations. It is shown that in this area the average length of spruce cones is in the range from 80-85 to 100-114 mm. The coefficient of narrowing of the upper part of the seed scales ( C ) is 25-35%, the coefficient of projection ( C ) is 60-80%, their difference ( C- C ) is -25… -55%. The value of the individual variation in the length of cones and the C index is 12-15%, C index is about 20%, and C-C is 30-35%. The intrapopulation coefficient of negative correlation of C and C indices has an average level (-0.3…-0.6). Their correlation between populations is much higher (-0.9). In the geographic variability of indicators of the shape of seed scales and the length of the cones, there is a correlation of the average level. The frequency of individuals of European spruce phenotypes in the populations of the groups P. ab, P. ab×ab×m., P. ab×m., Distinguished by the metric parameters of seed scales, is 98-100, 85-95, 57-70%, respectively. The research results can be useful for forestry and in substantiating the identified intraspecific taxa.

ФЕНОТИПИЧЕСКАЯ СТРУКТУРА ПОПУЛЯЦИЙ ЕЛИ НА ЕВРОПЕЙСКОМ СЕВЕРЕ РОССИИ

Spruce populations in the north of the European part of Russia have formed with traits, the population-geographic variability of which has not been sufficiently studied. The research purpose is to study on the basis of biometric parameters the phenotypic structure and geographic differentiation of spruce populations located north of the 60th parallel, as well as their relative position to European and Siberian spruces. Spruce is characterized here by a significant population-geographical diversity. The average length of cones in populations is within 44–85 mm, the coefficient of narrowing of the upper part of seed scales (Cn) is 36‒68, elongation coefficient (Cp) is 40‒60 %, and their difference (Cn‒Cp) is from ‒23 to +28 %. The coefficients of geographical variation are 15, 18, 12, and 61 %, respectively. By the value of the Cn‒Cp index, 6 groups of populations out of 9 (I‒IX) existing throughout the east of Europe and Siberia are distinguished, excluding the first three groups. There are intermediate phenotypes of individuals (f.emm., f.m., f.mms.) in groups IV, V and VI with the highest frequency (61, 72, 55 %), in groups VII, VIII and IX the highest frequency (71, 86, 98 %) is among Siberian spruce phenotypes (f.ms., f.mss., f.s.). The length of the cones varies significantly in the population groups: 70–80 mm on average in the first; 50–60 mm on average in the second. Population groups IV, V and VI represent an intermediate form of European and Siberian spruces and are distributed southwest of the conditional line between the rivers Pinega and Mezen to Syktyvkar. Groups VII, VIII and IX represent Siberian spruce and occupy the territory northeast of the specified line: the Arkhangelsk region, the territory of the Komi Republic, the Murmansk region and the northernmost part of Karelia. There are no populations representing European spruce in the region according to the studied characteristics. The results obtained can be used in the development of differentiated methods of forestry in the European North of Russia.

Zonificación altitudinal de Pinus patula a partir de conos y semillas en la sierra de Huayacocotla, Veracruz, México

Las poblaciones de especies forestales con amplia distribución tienden a diferenciarse en caracteres morfológicos a través de gradientes altitudinales. Esto permite establecer zonas para el movimiento de semillas, que garanticen la adaptación y un mejor crecimiento de las plantas. El patrón de variación morfológica asociado a gradientes altitudinales es desconocido para muchas especies de pinos mexicanos. Por lo tanto, se exploró la variación morfológica altitudinal con base en el largo y ancho de conos y semillas de 70 árboles superiores de Pinus patula seleccionados en ocho poblaciones de Huayacocotla, Veracruz, para establecer zonas provisionales para el movimiento de semillas. Se realizaron análisis de varianza y de asociación con variables geográficas. Se registró variación significativa entre y dentro de poblaciones para todas las características evaluadas y correlación positiva de la altitud con los caracteres de los conos y el ancho de las semillas. Con base en la variación del largo y ancho del cono, así como el ancho de semilla, se sugiere la delimitación provisional de dos zonas altitudinales (zona I: 1850 m - 2350 m snm; zona II: 2350 m - 2850 m snm), para el movimiento de semilla y reforestación. Se sugiere que la semilla de cada zona se utilice provisionalmente en un intervalo de ± 250 m altitudinales a partir de su origen, sin considerar el efecto del cambio climático y mover altitudinalmente hacia arriba las fuentes de semillas 250 m de altitud considerando el cambio climático, para reacoplar al clima proyectado para el año 2030, o 500 m para el de 2060.

Developmental indices of cones collected from male plants of Juniperus polycarpos K. Koch under in vitro water deficit and salt stress conditions

Cones of male plants have vital role in regeneration of plants especially in dioecious species propagated by sexual reproduction. Juniperus polycarpos K. Koch is an evergreen dioecious species with some problems at reproductive stage specially in arid and semi-arid regions. The purpose of this research was to evaluate the effects of water deficit and salinity stress on developmental indices of cones from male J. polycarpos. This research carried out in a complete randomized design with water deficit (2.5, 5, 7.5 and 9% PEG-6000) and salinity (100, 200 and 400 mM NaCl) treatments along with control. Explants with the same size (2.4 -2.6 cm) were taken from the shoot tip of male trees at a given time, decontaminated explants were placed on MS basal medium under aseptic condition. Both stresses significantly accelerated the date of cone from male plant maturation, this accelerating effect was reliant on stress treatments. Early maturation of cones from male J. polycarpos were observed at 7.5% PEG while aborted premature cones from male plants were obtained with the application of 9% PEG, and 200 or 400 mM NaCl. All treatments of water deficit and salt stress caused decrease in length, diameter and fresh weight of cones from male plants and number of microsporophyll per cone, which this effect had increasing trend with stress level. In fact, water deficit and salt stresses resulted in production of weak cones from male plants with irregular maturation and poor sexual reproduction. Due to extending of aridity in Southern part of Iran, tissue culture techniques can be suggested as a useful and relatively rapid method for reproductive and regenerative studies to protect J. polycarpos as a valuable species in ecological landscape.

ИНДИВИДУАЛЬНАЯ ИЗМЕНЧИВОСТЬ МОРФОЛОГИЧЕСКИХ ПРИЗНАКОВ ЛИСТВЕННИЦЫ ПОЛЬСКОЙ В УСЛОВИЯХ ИНТРОДУКЦИИ

Polish larch trees are among the most valuable among forest species both in natural growing conditions and in the conditions of introduction. However, its taxonomic status is not fully resolved due to the similarity in morphological features with European and Siberian larch. We conducted a comparative analysis of these species of larch on the morphological features of cones and needles. The studies were carried out in the conditions of introduction in the center of the European part of Russia. We present the average value of the trait (XSR ± Sx) and the degree of its variation (V %). The reliability of the difference between the samples according to these characteristics was determined based on the calculation of the student's criterion t. As a result, we found that the Polish larch has smaller cones and significantly differs from the European and Siberian larch in all studied features (length of cones, width of cones, number of scales in cones, length of needles). These results indicate the isolation of the Polish larch, but this pattern can be expressed not only when referring to the Polish larch in the rank of an independent species – Larix polonica Racib., but also as a subspecies of European larch (Larix decidua var. polonica (Racib. ex Wóycicki) Ostenf. & Syrach).

Cone and seeds variability in seed orchards and seed stands of Pinus sylvestris L.

Seeds from seed orchards and seed stands may differ in morphology and quality, both determined during the seed assessment. The study aims at the comparison of phenotypic characters of cones and seeds originating from economic seed stands and seed orchards of Scots pine from western Poland. The study was conducted in 5 seed stands and 5 clonal seed orchards, representing five Scots pine populations. The analyses included the following measurements: length and width of cones, the number of empty and full seeds in the cone and the weight of 1,000 seeds. Moreover, the measurements of the length and width of the seed surface were carried out.
 The analysed seed stands and orchards were characterized by high variability in terms of the size and weight of cones and the amount of seeds. An ANOVA treatment showed that seed stands and orchards significantly differed in length and width of cones and seeds. Both seeds and cones from the seed orchards were characterized by higher values of analyzed traits than ones from the economic seed stands. Differences in mass of cones and 1000 seed weigh were of low significance (p = 0.022 ÷ 0.037). Significant differences between the length of seeds and seed area among all of the examined populations were demonstrated. The percentage contribution of empty seeds for all of the analysed sites of origin was not statistically significant.
 
 
 
 Keywords: Scots pine, population, seed orchards, variation, seeds, cones

Role of serotiny on Pinus pinaster Aiton germination and its relation to mother plant age and fire severity

Abstract: Serotiny degree may hypothetically depend on mother plant age and fire severity, and fire severity can strongly affect the regeneration of Pinus pinaster Aiton, which is an obligate seeder species with aerial seed banks stocked in cones showing a certain degree of serotiny. The main objective of this study was to evaluate the effect of serotiny and mother plant age on seed germination of P. pinaster in relation to fire severity. For this purpose, cones were collected in two stands from mother trees of different ages. Serotinous cones were opened in oven at increasing temperatures to determine the number of seeds released. The length of cones and the number and weight of seeds were measured. Seeds from both classes of mother plant age were subjected to 34 different treatments simulating different fire severity levels, and their germination was recorded. The results showed that serotiny was significantly higher in cones from young mother trees. Seed germination in the control groups from serotinous cones was always higher than that from non-serotinous cones without thermal shock. Fire severity decreased seed germination as fire severity increases in both mother age classes. Mother plant age was related to the serotiny level, which was higher in young than in old trees, suggesting a strong selection in the population due to a recent fire.

Селекционно-генетический анализ лиственниц сибирской и Сукачева, интродуцированных в Москву и Подмосковье

The question of taxonomic status of Sukachev’s larch is still not understood to a full degree. There are arguments both in favor of separation of Siberian and Sukachev’s larches into individual species, and in favor of association them into the one. The issues of great importance are the works on the introduction of larch trees in the center of the European part of Russia in order to increase the resource potential of forests in this region. The study of variability of Siberian and Sukachev’s larches in the new climatic conditions, which take place during the introduction, can give interesting results important not only for discussion of their taxonomic rank, but for practical purposes of introduction. The paper presents comparative analysis of Siberian and Sukachev’s larches according to their individual variability of morphological characteristics and molecular genetic analysis. The studies were carried out in the conditions of introduction in Moscow (Main Botanical Garden named after N.V. Tsitsin) and Moscow region (Ivanteevskiy Arboretum). The morphological features of cones, needles and seeds were studied: length and width of cones, number of scales in them, length of needles, length and width of seeds. The arithmetic mean values of characters, the error of the arithmetic mean values of characters and the coefficient of variation were counted. On the basis of the obtained results, significant differences in morphological characteristics of cones, seeds and needles are established, which gives reasons to distinguish Sukachev’s larch as a geographical race; a subspecies of Siberian larch.For citation: Bryntsev V.A., Lavrenov M.A. Genetic Selection Analysis of Siberian and Sukachev’s Larches Introduced in Moscow and Moscow Region. Lesnoy Zhurnal [Forestry Journal], 2019, no. 4, pp. 9–21. DOI: 10.17238/issn0536-1036.2019.4.9

VARIABILITY OF CONES AND SEEDSCALESIN PICEA SPECIES AND THEIR FORMS IN CONDITIONS OF THE CITY OF OMSK

The study addressedthe morphometric indicators of cones and seed scales, such as length, width, and weight (before opening and after drying). Similarly, seed scales were measured, the marginal lines were described, and the number of seed scales in the cones was counted. The summary tables showed significant differences in the length and width of cones (Student's criterion). The correlation analysis was used to quantify the association between various indicators and the seed scale size. The samples were collected in the Genze Dendrological Garden, a natural landmark of regional significance. The study was carried out usingMolchanov and Smirnov’s (1967) method in the summer-autumn period. Siberian spruce (both blue and green forms), Serbian spruce, Colorado spruce (green form), and Canadian spruce had medium and large cones, which indicates a high adaptive capacity of these species. The length of cones in blue-grey and golden forms of Colorado spruce was below the average, indicating a low adaptive ability of the introduced species in the West Siberian foreststeppe. The correlation analysis showed a moderate dependence of the weight of seed scales and the weight of cones after drying (K = 0.60). A small dependence was found between the weight of seed scales and the length of cone after drying (K = 0.39). The size of seed scales strongly correlated with the size of cones (K ˃ 0.8). Student's t-test did not reveal significant differences in the width of cones in the studied species and forms of spruce, except for green form of Colorado spruce as compared to Serbian spruce and Canadian spruce, and blue-grey form of Colorado spruce as compared to Canadian spruce , showing notable differences at 1% significance point. By the length of cones, the studied species can be categorized into twoessentially different groups, the first one including all forms of Siberian spruce and Colorado spruce and the second one including Serbian spruce and Canadian spruce .

Вплив забруднення сульфітами та фторидами на накопичення біомаси квітковими рослинами

Вивчено реакцію 7 видів квітково-декоративних рослин на забруднення грунтуфторидами та сульфітами. Встановлено значну негативну дію забруднювачів на нако-пичення сирої та сухої маси усіма вивченими видами рослин. Найбільш стійкими зарезультатами дослідження виявилися кукіль звичайний (Agrostemma githago L.), кос-мея жовтогаряча (Соsmos sulphureus Cav.), льон звичайний (Linum usitatissimum L.).

Sеed productivity and quality of Picea abies and P. pungens in the Kriviy Rih plantations

Reproductive capability is considered as one of indicators of successful introduction; it helps to evaluate adaptation potential of plants, especially in techogenic conditions. The aim of our work is to research morphometric parameters of cones, profitability and seed quality of Рісеа аbies та P. pungens in the plantations with various levels of aerotechnogenic influence in conditions of an industrial city in the steppe zone of Ukraine. The objects of the studying were the cones of 30–40-year-old trees of P. аbies та P. pungens from eight different plantations situated along the whole city of Kryvyi Rih (126 km) and having various levels of technogenic pollution. We revealed that the maximal length of cone in two investigated species (108,4 and 88,7 mm respectively), width (28,6 and 24,7 mm); the highest seedling vigour (41,0 and 7,2 %), laboratory germination (54,2 and 20,6 %), seed mass (6,9 and 4,2 g), and length of germ (18,5 and 13,8 mm) are noted in the trees from Botanical Garden. The minimal values of all the same indices were ascertained for the trees growing near the metallurgical combine “ArcelorMittal Kryvyi Rih”: length of cones – 92,3 and 73,9 mm; width of cones – 26,2 and 22,4 mm; as well as the lowest seedling vigour (2,4 and 1,4 %); laboratory germination (5,0 and 2,0 %), seed mass (5,4 and 3,4 g), and length of germ (12,6 and 5,4 mm). The general seed quantity for a cone of P. аbies та P. pungens, in all the plantation types, varied from 203,9 to 217,2 seeds and from 198,6 to 204,3 ones respectively. The least part of fertile seeds (11,5–13,3 %), and the biggest part of sterile (56,5–58,7 %) and underdeveloped (29,8–30,1 %) ones were noted in the plants of P. pungens directly exposed to emissions of industrial enterprises; for the plants of P. abies the same indices were 20,2–22,5 %; 51,5–52,6 % та 26,0–27,2 % respectively. Therefore, increasing level of techogenic pollution by air pollutants, which is observed during some last years, oppresses the generative sphere of species of genus Рісеа in conditions of the steppe zone of Ukraine.

НАСІННА ПРОДУКТИВНІСТЬ СОСНИ КЕДРОВОЇ КОРЕЙСЬКОЇ (PINUS KORAIENSIS SIEB. ET ZUCC.) В МЕЖАХ ГАЛИЦЬКОГО НАЦІОНАЛЬНОГО ПРИРОДНОГО ПАРКУ


 
 
 
 _____________________________________
 Інформація про авторів:
 Мандзюк Роман Іванович, канд. с.-г. наук, наук. співробітник. Email: romanmandziuk@gmail.com
 Харачко Тарас Іванович, канд. с.-г. наук, доцент, кафедра лісових культур і лісової селекції. Email: taras-forester@ukr.net
 Цитування за ДСТУ: Мандзюк Р. І., Харачко Т. І. Насінна продуктивність сосни кедрової корейської (Pinus Koraiensis Sieb. et Zucc.) в межах Галицького національного природного парку. Scientific Bulletin of UNFU. 2018, т. 28, № 3. С. 00–00.
 Citation APA: Mandziuk, R. I., & Kharachko, T. I. (2018). On Seed Productivity of the Pinus Koraiensis (Sieb. et Zucc.) in Halych National Nature Park. SBUNFU, 28(3), 00–00. https://doi.org/10.15421/40280300
 
 
 
 
 Наведено коротку характеристику сосни кедрової корейської та проведено історичний екскурс щодо його появи у лісових насадженнях Галицького національного природного парку (Галицький НПП). Проаналізовано сучасні напрями досліджень виду у світі та зроблено висновок щодо актуальності його досліджень в Україні, а саме: доцільність вивчення процесів шишко- та насіннєношення, які безпосередньо впливають на насінну продуктивність. Описано результати фенологічних спостережень та встановлено періодичність шишконошення виду на постійній лісонасінній ділянці у Галицькому НПП. Висвітлено результати дослідження біометричних показників шишок і насіння кедрової корейської сосни. Результати досліджень свідчать про високу насінну продуктивність інтродуцента в умовах підприємства та дають підстави висловити припущення про збільшення цього показника впродовж кількох найближчих десятиліть, одночасно зі збільшенням віку шишконосних дерев. Встановлено оптимальні терміни заготівлі лісонасінної сировини та виявлено чинник, що впливає на зменшення врожаю шишок. Висвітлено результати інвентаризації самосіву досліджуваного виду на пробних ділянках та зроблено аналіз його висотної структури. Одночасно з обліком самосіву, наведено найхарактерний місця його появи в насадженні та висунуто припущення щодо причин його масового випадання впродовж другого та третього років життя. Проведене дослідження підтвердило натуралізацію виду в умовах Галицького НПП і вказало на притаманну для нього досить високу насінну продуктивність. Результати досліджень свідчать про можливість ширшого впровадження цього цінного, для лісового господарства, виду у лісові насадження регіону.

Fiber properties of axis and scale of eleven different coniferous cones

Fiber properties of eleven different coniferous cones, growing naturally in Turkey, were studied. Axis and scales of cones were analyzed separately. The slenderness, flexibility, and Runkel ratios were derived from measured fiber dimensions. Fiber length and fiber width of cones were between 0.93mm and 1.87mm, 16.6μm and 32.2μm, respectively. The longest fiber length was determined with 1.87mm in Pinus pinea cone axis fibers. Also, the widest fiber (32.2μm) and the widest lumen (20.0μm) were found in Abies equi-trojani cone scale fibers. The thickest cell wall (8.40μm) were found in Pinus sylvestris cone axis fibers. The sclerenchyma fibers, which were shorter and wider than fibers, were observed both in scale and axis of all cones. In general, cone axis fibers had lower slenderness and Runkel ratios and higher flexibility ratio than those of cone scale fibers. These results indicated that fiber properties of coniferous cones showed similarities with fibers of hardwood and nonwood species.

Reliability of linear distance measurements of surgical implants and gutta percha lengths used in endodontic treatment with standardized digital radiography

Aim: The length of gutta percha cones used in endodontic treatment and of dental implants used in dental surgery were compared with the lengths of periapical radiographs taken with phosphor plates and panoramic radiographs.
 Methodology: This study included 120 radiographs: 60 panoramic and 60 periapical radiographs, 30 of dental implants and 30 of gutta percha cones. The actual length and width measurements of both implants and gutta percha cones were compared with panoramic radiographs and length and width measurements on periapical radiographs.
 Results: When the measurements made on panoramic and periapical radiographs taken with phosphor plates were evaluated statistically, it was apparent that the periapical radiographs taken with phosphor plate showed less magnification error than did those taken with the panoramic technique.
 Conclusions: Clinicians should be aware of the limitations of the techniques used in clinical dentistry, comparing data obtained with digital radiographs of surgical implants and gutta percha cones. 
 Keywords: Implant length, gutta percha length, standardized digital radiography, dental x-ray measurement
 How to cite this article: Colak M, Adiguzel O, Aktuna Belgin C, Falakaloglu S, Akkus Z. Reliability of linear distance measurements of surgical implants and gutta percha lengths used in endodontic treatment with standardized digital radiography. Int Dent Res 2017;7:1-5.
 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

LIM Kinase 1 (LIMK1) Interacts with Tropomyosin-related Kinase B (TrkB) and Mediates Brain-derived Neurotrophic Factor (BDNF)-induced Axonal Elongation

BDNF/TrkB signaling plays critical roles in axonal outgrowth of neurons, the process of which requires the remodeling of the cytoskeleton structure, including microtubules and filamentous actin. However, the mechanism by which BDNF/TrkB signaling regulates cytoskeleton reorganization is still unclear. Here, we identified a novel interaction between LIMK1 and TrkB, which is required for the BDNF-induced axonal elongation. We demonstrated that BDNF-induced TrkB dimerization led to LIMK1 dimerization and transphosphorylation independent of TrkB kinase activity, which could further enhance the activation and stabilization of LIMK1. Moreover, activated LIMK1 translocated to the membrane fraction and phosphorylated its substrate cofilin, thus promoting actin polymerization and axonal elongation. Our findings provided evidence of a novel mechanism for the BDNF-mediated signal transduction leading to axonal elongation.

Body mass, phylogeny and diet composition affects kidney morphology in passerine birds

We studied the renal morphology of 16 species of passerines to assess whether the composition of the diet of birds have been paralleled by differences in the characteristics of the kidneys. We determined the number and length of the medullary cones and the percentage of renal medulla in birds with contrasting dietary habits and then correlated these features with the percentage of nitrogen and proportion of invertebrates in the diet. To examine the correlation between kidney and diet variables, we first used standard correlation and least square regression, and correlation and regression on phylogenetically independent data. We found that the mass of the medullary portion of the kidney, and the medullary cone length were negatively correlated with the percentage of invertebrates present in the diet. We hypothesized that the further development of the renal medulla observed in granivorous birds may be correlated with the small amount of water present in the seeds. Our results suggest that the availability of water in different foods is probably one of the main factors that have led to structural and probably functional changes of the kidney in the studied species.

Expression in the mammalian retina of parkin and UCH-L1, two components of the ubiquitin-proteasome system

The ubiquitin-proteasome system (UPS) functions as a major degradation pathway for misfolded and damaged proteins with an important neuroprotective role in the CNS against a variety of cellular stresses. Parkin and ubiquitin C-terminal hydrolase L1 (UCH-L1) are two relevant components of the UPS associated with a number of neurodegenerative disorders. We here address the expression profile of parkin and UCH-L1 in the mammalian retina, with special emphasis on primates. We describe for the first time the presence of parkin in the retina of mammals, including humans. Parkin and UCH-L1 genes were expressed at the mRNA and protein levels in the retina of all species examined. The immunolocalization pattern of parkin was quite widespread, being expressed by most retinal neuronal types, including photoreceptors. UCH-L1 was localized to horizontal cells and specific subtypes of bipolar and amacrine cells, as well as to ganglion cells and their axons forming the nerve fiber layer. In rodents no UCH-L1 immunoreactivity was found in cone or rod photoreceptors, whereas this protein was present along the whole length of cones in all other mammals. Remarkably, UCH-L1 was expressed by dopaminergic amacrine cells of primates. The ample distribution of parkin and UCH-L1 in the mammalian retina, together with the crucial role played by the UPS in normal neuronal physiology in the brain, points to a participation of these two proteins in the ubiquitin-proteasomal pathway of protein degradation in most retinal cell types, where they could exert a protective function against neuronal stress.