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Objective: Skin brightness and spot have a significant impact on youthful and beautiful appearance. One important factor influencing skin brightness is the amount of internal reflected light from the skin. Observers recognize the total surface-reflected light and internal reflected light as skin brightness. The more internal reflected light from the skin, the more attractive and brighter the skin appears. This study aims to identify a new natural cosmetic ingredient that increases the skin's internal reflected light, decreases spot and provides a youthful and beautiful skin appearance., Methods: Lipofuscin in epidermal keratinocytes, the aggregating complex of denatured proteins and peroxidized lipids, is one factor that decreases skin brightness and causes of spot. Aggregates block light transmission, and peroxidized lipids lead to skin yellowness, dullness and age spot. Lipofuscin is known to accumulate intracellularly with ageing. Rapid removal of intracellular denatured proteins prevents lipofuscin formation and accumulation in cells. We focused a proteasome system that efficiently removes intracellular denatured proteins. To identify natural ingredients that increase proteasome activity, we screened 380 extracts derived from natural products. The extract with the desired activity was fractionated and purified to identify active compounds that lead to proteasome activation. Finally, the efficacy of the proteasome-activating extract was evaluated in a human clinical study., Results: We discovered that Juniperus communis fruits (Juniper berry) extract (JBE) increases proteasome activity and suppresses lipofuscin accumulation in human epidermal keratinocytes. We found Anthricin and Yatein, which belong to the lignan family, to be major active compounds responsible for the proteasome-activating effect of JBE. In a human clinical study, an emulsion containing 1% JBE was applied to half of the face twice daily for 4 weeks, resulting in increased internal reflected light, brightness improvement (L-value) and reduction in yellowness (b-value) and spot in the cheek area., Conclusion: This is the first report demonstrating that JBE containing Anthricin and Yatein decreases lipofuscin accumulation in human epidermal keratinocytes through proteasome activation, increases brightness and decreases surface spots in human skin. JBE would be an ideal natural cosmetic ingredient for creating a more youthful and beautiful skin appearance with greater brightness and less spot., (© 2023 Society of Cosmetic Scientists and Societe Francaise de Cosmetologie.)

The berries of Juniperus communis have been traditionally used for therapeutic purposes. They have been reported to possess various pharmacological effects such as anti-inflammatory, hypoglycemic and hypolipidemic activities. In this study, a methanolic extract of J. communis berries (JB) was evaluated for its effects on peroxisome proliferator-activated receptors alpha and gamma (PPAR α and PPAR γ ), liver X receptor (LXR), glucose uptake and lipid accumulation using various cellular systems. At a concentration of 25  μ g/mL, JB caused 3.77-fold activation of PPAR α , 10.90-fold activation of PPAR γ , and 4.43-fold activation of LXR in hepatic cells. JB inhibited (11%) the adipogenic effect induced by rosiglitazone in adipocytes and increased glucose uptake (90%) in muscle cells. In high-fat diet (HFD) fed mice, JB at a dose of 25 mg/kg body weight exhibited a 21% decrease in body weight. Fasting glucose levels in mice treated with 12.5 mg/kg of JB were significantly decreased (39%) indicating its efficacy in regulating hyperglycemia and obesity induced by HFD thus ameliorating the symptoms of type 2 diabetes. A series of energy metabolic genes, including Sirt1 (2.00-fold) and RAF1 (2.04-fold), were upregulated by JB, while rosiglitazone regulated the hepatic PPAR γ only. Phytochemical analysis of JB indicated presence of a number of flavonoids and biflavonoids which seem to be responsible for the observed activity. It was concluded that JB acted as a multiple agonist of PPAR α , PPAR γ and LXR without the undesired effect of adipogenesis and exhibited the property of enhancing glucose uptake. The regulation of PPAR α , PPAR γ and LXR seems to be through Sirt1 and RAF1. In vivo results confirmed the antidiabetic and antiobesity potential of JB and indicated its utility in metabolic disorder and type 2 diabetes.

Climate change is increasing the variability of precipitation, altering the frequency of soil drying-wetting events and the distribution of seasonal precipitation. These changes in precipitation can alter nitrogen (N) cycling and stimulate nitric oxide (NO) emissions (an air pollutant at high concentrations), which may vary according to legacies of past precipitation and represent a pathway for ecosystem N loss. To identify whether precipitation legacies affect NO emissions, we excluded or added precipitation during the winter growing season in a Pinyon-Juniper dryland and measured in situ NO emissions following experimental wetting. We found that the legacy of both excluding and adding winter precipitation increased NO emissions early in the following summer; cumulative NO emissions from the winter precipitation exclusion plots (2750 ± 972 μg N-NO m -2 ) and winter water addition plots (2449 ± 408 μg N-NO m -2 ) were higher than control plots (1506 ± 397 μg N-NO m -2 ). The increase in NO emissions with previous precipitation exclusion was associated with inorganic N accumulation, while the increase in NO emissions with previous water addition was associated with an upward trend in microbial biomass. Precipitation legacies can accelerate soil NO emissions and may amplify ecosystem N loss in response to more variable precipitation., (© 2022 The Ecological Society of America.)

Proteins related to DNA replication have been proposed as cancer biomarkers and targets for anticancer agents. Among them, minichromosome maintenance (MCM) proteins, often overexpressed in various cancer cells, are recognized both as notable biomarkers for cancer diagnosis and as targets for cancer treatment. Here, we investigated the activity of cedrol, a single compound isolated from Juniperus chinensis , in reducing the expression of MCM proteins in human lung carcinoma A549 cells. Remarkably, cedrol also strongly inhibited the expression of all other MCM protein family members in A549 cells. Moreover, cedrol treatment reduced cell viability in A549 cells, accompanied by cell cycle arrest at the G1 phase, and enhanced apoptosis. Taken together, this study broadens our understanding of how cedrol executes its anticancer activity while demonstrating that cedrol has potential application in the treatment of human lung cancer as an inhibitor of MCM proteins.

The vast diversity of cytochrome P450 enzymes in mammals has been proposed to result in large measure from plant-animal warfare, whereby evolution of chemical defenses such as phenolics and terpenoids in plants led to duplication and divergence of P450 genes in herbivores. Over evolutionary time, natural selection is predicted to have produced P450s with high affinity and enhanced metabolism of substrates that are ingested regularly by herbivores. Interestingly, however, almost all knowledge of the interactions of mammalian P450 enzymes with substrates stems from studies of the metabolism of drugs and model compounds rather than studies on wild mammalian herbivores and their respective PSMs. A question of particular interest centers on the role of individual P450 enzymes in the ability of certain herbivores to specialize on plants that are lethal to most other species, including those from the same genus as the specialists. We tackled this intricate problem using a tractable natural system (herbivorous woodrats, genus Neotoma) focusing on comparisons of the specialist N. stephensi, the facultative specialist N. lepida, and the generalist N. albigula, and employing a cross-disciplinary approach involving ecology, biochemistry, pharmacology, structural biology, and genomics. Based on multiple findings suggesting the importance of CYP2B enzymes for ingestion of juniper and a major constituent, α-pinene, we characterized the structure, function and activity of several CYP2B enzymes in woodrats with different dietary habits. Results to date suggest that differences in CYP2B gene copy number may contribute to differential tolerance of PSMs among woodrat species, although additional work is warranted to firmly link gene copy number to juniper tolerance., Competing Interests: Conflict of interest statement The authors have no conflicts of interest to declare., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Juniperus excelsa M. Bieb and J. sabina L. contain essential oil (EO), while J. sabina also contains podophyllotoxin, which is used as a precursor for anti-cancer drugs. Two studies were conducted. The first assessed the variability in the EO profile and podophyllotoxin concentration of the two junipers, depending on the location and tree gender. The main EO constituents of J. excelsa were α-cedrol, α-limonene and α-pinene, while the constituents in J. sabina were sabinene, terpinen-4-ol, myrtenyl acetate and α-cadinol. The podophyllotoxin yield of 18 J. sabina accessions was 0.07-0.32% ( w/w ), but this was not found in any of the J. excelsa accessions. The second study assessed the effect of hydrodistillation (Clevenger apparatus) and steam distillation (in a semi-commercial apparatus) on the EO profile and bioactivity. The extraction type did not significantly alter the EO composition. The EO profiles of the two junipers and their accessions were different and may be of interest to the industry utilizing juniper leaf EO. Breeding and selection programs could be developed with the two junipers (protected species) in order to identify chemotypes with (1) a high EO content and desirable composition, and (2) a high concentration of podophyllotoxin in J. sabina . Such chemotypes could be established as agricultural crops for the commercial production of podophyllotoxin and EO.

The expansion of woody plants into grasslands and old fields is often ascribed to fire suppression and heavy grazing, especially by domestic livestock. However, it is also recognized that nutrient availability and interspecific competition with grasses and other woody plants play a role in certain habitats. I examined potential factors causing range- and niche expansion by the eastern redcedar Juniperus virginiana, the most widespread conifer in the eastern United States, in multifactorial experiments in a greenhouse. Historical records suggest that the eastern redcedar is a pioneer forest species, and may be replaced as the forest increases in tree density due to shading. Another possible factor that affects its distribution may be nutrient availability, which is higher in old fields and other disturbed lands than in undisturbed habitats. In its historic range, eastern redcedars are particularly abundant on limestone outcrops, often termed 'cedar barrens'. However, the higher abundance on limestone could be due to reduced interspecific competition rather than a preference for high pH substrates. I manipulated shade, fertilization, lime, and interspecific competition with a common dominant tree, the post oak Quercus stellata. In a separate experiment, I manipulated fire and grass competition. I measured growth rates (height and diameter) and above- and belowground biomass at the end of both experiments. I also measured total non-structural carbohydrates and nitrogen in these plants. Shade was the most important factor limiting the growth rates and biomass of eastern redcedars. I also found that there were significant declines in nitrogen and non-structural carbohydrates when shaded. These results are consistent with the notion that the eastern redcedar is a pioneer forest species, and that shade is the reason that these redcedars are replaced by other tree species. In the second experiment, I found that a single fire had a negative effect on young trees. There was no significant effect of competition with grass, perhaps because the competitive effect was shading by grasses and not nutrient depletion. Overall, the effects of shade were far more apparent than the effects of fire., Competing Interests: The author declares that no competing interests exist.

Seasonal aeroallergens commonly cause allergic conjunctivitis, rhinorrhea, sinusitis, and cough in sensitized individuals. These clinical symptoms are the result of IgE-mediated type I hypersensitivity reactions, which trigger the degranulaton of mast cells and basophils. In contrast, aeroallergens are not common precipitants of urticarial dermatitis, which is driven by a cell-mediated type IV hypersensitivity reaction. In this case report, we describe an Active Duty Air Force member stationed in San Antonio, TX, who presented to the dermatology clinic with a three year history of recalcitrant urticarial dermatitis found to be directly related to exposure to the pollen from the Juniperus ashei tree, also referred to as Mountain Cedar. While laboratory findings confirmed a high level of circulating IgE antibody to Mountain Cedar, the patient had no upper respiratory symptoms consistent with a typical allergic reaction. Further, his skin disease rapidly cleared within 24 hours of leaving southern Texas. Because of the recalcitrant nature of his condition upon returning home, he was considered unfit for further military service. This case not only highlights the growing link between IgE and chronic skin disease, but also the impact aeroallergens can have on the medical readiness and world-wide deployability of Airmen, Sailors, Soldiers, and Marines., (Published by Oxford University Press on behalf of the Association of Military Surgeons of the United States 2019. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Climate warming should result in hotter droughts of unprecedented severity in this century. Such droughts have been linked with massive tree mortality, and data suggest that warming interacts with drought to aggravate plant performance. Yet how forests will respond to hotter droughts remains unclear, as does the suite of mechanisms trees use to deal with hot droughts. We used an ecosystem-scale manipulation of precipitation and temperature on piñon pine (Pinus edulis) and juniper (Juniperus monosperma) trees to investigate nitrogen (N) cycling-induced mitigation processes related to hotter droughts. We found that while negative impacts on plant carbon and water balance are manifest after prolonged drought, performance reductions were not amplified by warmer temperatures. Rather, increased temperatures for 5 years stimulated soil N cycling under piñon trees and modified tree N allocation for both species, resulting in mitigation of hotter drought impacts on tree water and carbon functions. These findings suggest that adjustments in N cycling are likely after multi-year warming conditions and that such changes may buffer reductions in tree performance during hotter droughts. The results highlight our incomplete understanding of trees' ability to acclimate to climate change, raising fundamental questions about the resistance potential of forests to long-term, compound climatic stresses., (© 2018 John Wiley & Sons Ltd.)

We investigated stem radial growth and water storage dynamics of 2 conifer species differing in hydraulic carbon strategies, Juniperus monosperma and Pinus edulis, under conditions of ambient, drought (∼45% reduction in precipitation), heat (∼4.8 °C temperature increase), and the combination of drought + heat, in 2013 and 2014. Juniper maintained low growth across all treatments. Overall, the relatively isohydric piñon pine showed significantly greater growth and water storage recharge than the relatively anisohydric juniper across all treatments in the average climate year (2014) but no differences in the regionally dry year (2013). Piñon pine ceased growth at a constant predawn water potential across all treatments and at a less negative water potential threshold than juniper. Heat has a greater negative impact on piñon pines' growth and water storage than drought, whereas juniper was, in contrast, unaffected by heat but strongly impacted by drought. The whole-plant hydraulic carbon strategies, in this case captured using the isohydric/anisohydric concept, translate into alternative growth and water storage strategies under drought and heat conditions., (© 2018 John Wiley & Sons Ltd.)

Background/aims: Herbal materials derived from Juniperus communis (JCo) possess anticancer activity. In this study, we evaluated the efficacy of a JCo berry extract in suppressing glioblastoma growth., Methods: The effects of JCo extract on the viability of normal and glioma cell lines was analyzed using a modified 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The synergistic therapeutic effect of JCo extract and temozolomide (TMZ) on glioma cells was examined by MTT analysis. Flow cytometry analysis, the terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) test, and western blotting were performed to identify the apoptotic pathway. To determine the in vivo efficacy of the JCo extract, rats were injected with 5 × 104 rat glioma RG2 cells in the back skin and brain hemisphere and then received a subcutaneous injection in the back skin that contained either JCo extract or vehicle. Finally, blood and histologic examinations were performed to evaluate JCo toxicity., Results: The IC50 values of JCo extract were 57-69 µg/mL and 49-67 µg/mL in the glioblastoma cell lines after 24 and 48 h, respectively. However, in non-tumor cell lines, the respective IC50 values of JCo extract were 76-105 µg/mL and 77-108 µg/mL. The JCo extract had a stronger cytotoxicity and a larger range of IC50 values in glioma than in normal cells as compared to those effects caused by temozolomide (TMZ). In addition, the results of flow cytometry analysis, TUNEL test, and western blotting revealed that the JCo extract induced glioma cell cycle arrest through intrinsic and extrinsic apoptotic pathways. In the in vivo studies, a significant reduction of tumor size in JCo-treated rats, as measured by animal MRI, demonstrated that the JCo extract effectively inhibited glioma cell growth and successfully penetrated the blood-brain barrier. The immunohistochemical (IHC) staining detected positive signals of PCNA, VEGFR-1, and VEGFR -2 in 44.49%, 5.88%, and 5.85% of JCo-treated glioma cells, respectively. However, positive signals of PCNA, VEGFR-1, and VEGFR-2 were detected in 73.08%, 9.67%, and 11.70% of vehicle-treated glioma cells, respectively. The IHC examination of PCNA and VEGFR-1 and -2 indicated that JCo extract significantly decreased the degree of neovascularization. However, no significant differences in serum levels of blood cell count and hepatic enzymes, renal function index, and the histologic appearance of vital organs were detected between the JCo and vehicle-treated rats., Conclusion: The JCo extract penetrated the blood-brain barrier and significantly induced glioma cell apoptosis by reducing neovascularization via suppression of the PI3K/AKT/mTOR pathway. Furthermore, JCo extract was less cytotoxic to non-neoplastic vital organs than TMZ., (© 2018 The Author(s). Published by S. Karger AG, Basel.)

The allelopathic effects of Juniperus rigida litter aqueous extract (LE) on wheat and Pinus tabuliformis were studied, as well as the physiological responses to the extract. High concentration LE (0.10 g Dw/ml) significantly inhibited the seed germination and seedling growth in receptor plants. The chlorophyll content and root activity in the wheat seedlings were reduced significantly across all treatments; however, those were more prominently reduced at high concentration (0.10 g Dw/ml) but received little stimulation at low concentration (0.025 g Dw/ml) in P. tabuliformis. The content of malonaldehyde (MDA) increased with increasing concentrations of LE, except at 0.025 g Dw/ml. Activities of antioxidant enzymes (POD, CAT and SOD) in receptor plants were all significantly inhibited at high concentrations but stimulated at low concentrations. These results demonstrate that the aqueous extract from J. rigida litter has allelopathic potential. Various phenolic compounds were identified in litter aqueous extract and litter ethanol extract by HPLC. The phenolic compound content in the aqueous extract was significantly lower than that in the ethanol extract. Chlorogenic acid and podophyllotoxin were the predominant phenolic compounds in both types of litter extracts. These findings suggest that the seed germination and seedling growth of P. tabuliformis and wheat would be inhibited when planted near large amounts J. rigida litter., (© 2017 Wiley-VHCA AG, Zurich, Switzerland.)

Herbivores employ numerous strategies to reduce their exposure to toxic plant secondary chemicals (PSCs). However, the physiological mechanisms of PSC absorption have not been extensively explored. In particular, the absorption of PSCs via intestinal lymphatic absorption has been largely overlooked in herbivores, even though this pathway is well recognized for pharmaceutical uptake. Here, we investigated for the first time whether PSCs might be absorbed by lymphatic transport. We fed woodrats (Neotoma albigula) diets with increasing concentrations of terpene-rich juniper (Juniperus monosperma) either with or without a compound that blocks intestinal lymphatic absorption (Pluronic L-81). Woodrats consuming diets that contained the intestinal lymphatic absorption blocker exhibited increased food intakes and maintained higher body masses on juniper diets. Our study represents the first demonstration that PSCs may be absorbed by intestinal lymphatic absorption. This absorption pathway has numerous implications for the metabolism and distribution of PSCs in the systemic circulation, given that compounds absorbed via lymphatic transport bypass first-pass hepatic metabolism. The area of lymphatic transport of PSCs represents an understudied physiological pathway in plant-herbivore interactions.

Plant tissue cultures are a potential source of secondary metabolites. However, their production, when compared with intact plants, is usually lower. Phenylalanine, a biogenetic precursor of podophyllotoxin, was used to stimulate podophyllotoxin production in callus and suspension cultures of Juniperus virginiana L. The best phenylalanine effect on podophyllotoxin production was manifested in three-years-old callus cultures after a 21-days application of a 10 mmol/L concentration. A podophyllotoxin content of 0.15 mg/g DW was determined, which was about 400% higher in comparison with the control. The maximum content (0.48 mg/g DW) in newly derived suspension cultures (the 4' passage) was induced by 14-days application of a I mmol/L concentration; this was about 243% higher than the control. In one-year-old suspension cultures the highest podophyllotoxin content (0.56 mg/g DW) was recorded also after 14-days application of a I mmol/L concentration; this was about 211% higher than in the control cultures.

Recent droughts in southwestern USA have led to large-scale mortality of piñon (Pinus edulis) in piñon-juniper woodlands. Piñon mortality alters soil moisture, nutrient and carbon availability, which could affect the root-associated fungal (RAF) communities and therefore the fitness of the remaining plants. We collected fine root samples at a piñon-juniper woodland and a juniper savannah site in central New Mexico. Roots were collected from piñon and juniper (Juniperus monosperma) trees whose nearest neighbors were live piñon, live juniper or dead piñon. RAF communities were analyzed by 454 pyrosequencing of the universal fungal ITS region. The most common taxa were Hypocreales and Chaetothyriales. More than 10% of ITS sequences could not be assigned taxonomy at the phylum level. Two of the unclassified OTUs significantly differed between savanna and woodland, had few like sequences in GenBank and formed new fungal clades with other unclassified RAF from arid plants, highlighting how little study has been done on the RAF of arid ecosystems. Plant host or neighbor did not affect RAF community composition. However, there was a significant difference between RAF communities from woodland vs. savanna, indicating that abiotic factors such as temperature and aridity might be more important in structuring these RAF communities than biotic factors such as plant host or neighbor identity. Ectomycorrhizal fungi (EM) were present in juniper as well as piñon in the woodland site, in contrast with previous research, but did not occur in juniper savanna, suggesting a potential shared EM network with juniper. RAF richness was lower in hosts that were neighbors of the opposite host. This may indicate competitive exclusion between fungi from different hosts. Characterizing these communities and their responses to environment and plant neighborhood is a step toward understanding the effects of drought on a biome that spans 19,000,000 ha of southwestern USA., (© 2015 by The Mycological Society of America.)

Optimal allocation of resources is crucial to maximize plant success. Plants modify their economic strategies by adjusting functional traits in response to shifts in environmental conditions. Facilitation has been recognized as a major biotic filter of trait distribution in communities, although the effect of facilitation on intraspecific variability has been scarcely explored. We evaluated intraspecific shifts in leaf functional traits of a perennial forb (Helleborus foetidus) in relation to the presence of a nurse plant (Juniperus sabina) in two sites with contrasting abiotic stress levels. The effects of abiotic (site) and biotic (juniper presence, microsite) environments on specific leaf area (SLA), leaf area (LA), lamina/petiole length ratio (LPR), intrinsic water use efficiency (iWUE) and leaf nutrient content (N, P and N:P) per mass were evaluated. Alleviation of drought stress associated with nurse plant presence was reflected in SLA, LA, LPR and iWUE at the high-stress site. Individuals growing in open areas showed more resource-conservative traits, supporting the argument that this strategy is advantageous in environments that limit opportunities for rapid carbon gain. Leaf nutrients were unrelated to other traits. The large amount of intraspecific variation in leaf functional traits related to facilitative processes highlights the importance of facilitation as a major source of plant trait variation. Both positive and negative biotic interactions, as well as intraspecific trait variability, should be considered in mechanistic models of plant communities' functional responses to environmental changes.

Chlorhexidine (CHX), one of the most effective drugs administered for periodontal treatment, presents collateral effects including toxicity when used for prolonged periods; here, we have evaluated the bactericidal potency and the cytocompatibility of Juniperus excelsa M. Bieb essential oil (EO) in comparison with 0.05% CHX. The EO was extracted from berries by hydrodistillation and components identified by gas chromatography and mass spectrometry. Bacterial inhibition halo analysis, quantitative cell viability 2,3-bis(2-methoxy-4-nitro-5-sulphophenyl)-5-[(phenyl amino) carbonyl]-2H-tetrazolium hydroxide assay (XTT), and colony forming unit (CFU) count were evaluated against the two biofilm formers Aggregatibacter actinomycetemcomitans and Streptococcus mutans. Finally, cytocompatibility was assessed with human primary gingival fibroblasts (HGF) and mucosal keratinocytes (HK). The resulting EO was mainly composed of monoterpene hydrocarbons and oxygenated monoterpenes. An inhibition halo test demonstrated that both bacteria were sensitive to the EO; XTT analysis and CFU counts confirmed that 10-fold-diluted EO determined a statistically significant (p < 0.05) reduction in bacteria count and viability towards both biofilm and planktonic forms in a comparable manner to those obtained with CHX. Moreover, EO displayed higher cytocompatibility than CHX (p < 0.05). In conclusion, EO exhibited bactericidal activity similar to CHX, but a superior cytocompatibility, making it a promising antiseptic alternative to CHX.

The photosynthesis in evergreen trees living in Mediterranean ecosystems is subjected to multiple climatic stresses due to water shortage and high temperatures during the summer and to low temperatures during the winter. Mediterranean perennials deploy different photoprotective mechanisms to prevent damage to the photosynthetic system. Wax accumulation in leaves is a primary response which by enhancing light scattering in the leaf surface reduces incident radiation in the mesophyll. The existence of high variability in wax accumulation levels between coexisting individuals of a species has a visual effect on colour that provides distinguishable green and glaucous phenotypes. We explored this variability in a Mediterranean evergreen tree Juniperus thurifera (L.) to evaluate the impact of epicuticular wax on optical and ecophysiological properties and on the abundance of photoprotective pigments throughout an annual cycle. Because of light attenuation by waxes, we expected that glaucous phenotypes would lower the need for photoprotective pigments. We evaluated the effect of phenotype and season on reflectance, defoliation levels, photochemical efficiency and photoprotective pigment contents in 20 green and 20 glaucous junipers. Contrary to our expectations, the results showed that glaucous trees suffered from a diminution in photochemical efficiency, but there was no reduction in photoprotective pigments. Differences between glaucous and green phenotypes were greater in winter, which is the most stressful season for this species. Glaucous individuals also showed the highest levels of leaf defoliation. The lower photochemical efficiency of glaucous trees, together with higher defoliation rates and equal or greater number of physiological photoprotective mechanisms, suggests that in spite of wax accumulation, glaucous trees suffer from more severe stress than green ones. This result suggests that changes in colouration in Mediterranean evergreens may be a decline indicator.

Differential plant use by herbivores has been observed for several woody plant species and has frequently been attributed to plant secondary metabolites. We examined the relationship between terpenoid concentration and Juniperus monosperma herbivory by small ruminants. Two groups of animals (10 goats or 5 goats plus 4 sheep) browsed 16 paddocks (20 × 30 m) containing one-seed juniper for six days during two seasons. Juniper leaves were sampled from 311 saplings immediately after browsing. Saplings were categorized by size (short [<0.5 m], medium [0.5-1.0 m], or tall [>1.0 m]), and by browsing intensity (light [<33 %], moderate [33-66 %], or heavy [>66 %]). Juniper bark was collected from 12 saplings during spring. Total estimated terpenoid concentrations in leaves and bark were 18.3 ± 0.3 and 8.9 ± 0.8 mg/g, respectively, and the dominant terpene in both tissues was α-pinene (11.1 ± 0.2 and 7.6 ± 0.7 mg/g, respectively). Total terpenoid concentration of juniper leaves was greater in spring than summer (20.6 ± 0.5 vs. 16.7 ± 0.3 mg/g, respectively) and was lower in short saplings than medium or tall saplings (16.5 ± 0.6 vs. 19.8 ± 0.4 and 19.5 ± 0.4 mg/g, respectively). Total terpenoid concentration of leaves also differed among the three defoliation categories (21.2 ± 0.6, 18.7 ± 0.5, and 16.1 ± 0.4 mg/g for light, moderate, and heavy, respectively). The smallest subset of terpenoids able to discriminate between light and heavy browsing intensity categories included eight compounds ([E]-β-farnesene, bornyl acetate, γ-eudesmol, endo-fenchyl acetate, γ-cadinene, α-pinene, cis-piperitol, and cis-p-menth-2-en-1-ol). Our results suggest terpenoid concentrations in one-seed juniper are related to season, sapling size, and browsing by small ruminants.

Using dendroisotopic techniques, we show the recovery of Juniperus virginiana L. (eastern red cedar) trees in the Central Appalachian Mountains from decades of acidic pollution. Acid deposition over much of the 20th century reduced stomatal conductance of leaves, thereby increasing intrinsic water-use efficiency of the Juniperus trees. These data indicate that the stomata of Juniperus may be more sensitive to acid deposition than to increasing atmospheric CO2. A breakpoint in the 100-y δ(13)C tree ring chronology occurred around 1980, as the legacy of sulfur dioxide emissions declined following the enactment of the Clean Air Act in 1970, indicating a gradual increase in stomatal conductance (despite rising levels of atmospheric CO2) and a concurrent increase in photosynthesis related to decreasing acid deposition and increasing atmospheric CO2. Tree ring δ(34)S shows a synchronous change in the sources of sulfur used at the whole-tree level that indicates a reduced anthropogenic influence. The increase in growth and the δ(13)C and δ(34)S trends in the tree ring chronology of these Juniperus trees provide evidence for a distinct physiological response to changes in atmospheric SO2 emissions since ∼1980 and signify the positive impacts of landmark environmental legislation to facilitate recovery of forest ecosystems from acid deposition.

This study investigates the potential for extracting sugars from the polysaccharides of Eastern redcedar. Pretreatment temperature, time, sulfuric acid loading, sodium bisulfite loading and impregnation time were varied using factorial treatment design experiments for identifying near optimal overall wood glucan-to-glucose yields during acid bisulfite pretreatments. The highest overall wood glucan-to-glucose yield of 87% was achieved when redcedar was impregnated with pretreatment liquor containing 3.75 g of sulfuric acid/100g of dry wood and 20 g of sodium bisulfite/100g of dry wood at 90 °C for 3h followed by increasing the temperature to 200 °C with a hold time of 10 min. Hemicellulose and lignin removal during pretreatments made the substrate amenable to enzymatic hydrolysis using 0.5 ml of Accelerase® 1500/g of glucan at 2% (w/w) solid loading. Preliminary mass balances showed 97% glucan recovery at pretreatment condition with 87% overall wood glucan-to-glucose yield and 59% delignification., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Rationale: Globally, many drylands are experiencing the encroachment of woody vegetation into grasslands. These changes in ecosystem structure and processes can result in increased sediment and nutrient fluxes due to fluvial erosion. As these changes are often accompanied by a shift from C(4) to C(3) vegetation with characteristic δ(13) C values, stable isotope analysis provides a promising mechanism for tracing these fluxes., Methods: Input vegetation, surface sediment and fluvially eroded sediment samples were collected across two contrasting C(4) -C(3) dryland vegetation transitions in New Mexico, USA. Isotope ratio mass spectrometric analyses were performed using a Carlo Erba NA2000 analyser interfaced to a SerCon 20-22 isotope ratio mass spectrometer to determine bulk δ(13) C values., Results: Stable isotope analyses of contemporary input vegetation and surface sediments over the monitored transitions showed significant differences (p <0.05) in the bulk δ(13) C values of C(4) Bouteloua sp. (grama) grassland, C(3) Larrea tridentata (creosote) shrubland and C(3) Pinus edulis/Juniperus monosperma (piñon-juniper) woodland sites. Significantly, this distinctive δ(13) C value was maintained in the bulk δ(13) C values of fluvially eroded sediment from each of the sites, with no significant variation between surface sediment and eroded sediment values., Conclusions: The significant differences in bulk δ(13) C values between sites were dependent on vegetation input. Importantly, these values were robustly expressed in fluvially eroded sediments, suggesting that stable isotope analysis is suitable for tracing sediment fluxes. Due to the prevalent nature of these dryland vegetation transitions in the USA and globally, further development of stable isotope ratio mass spectrometry has provided a valuable tool for enhanced understanding of functional changes in these ecosystems., (Copyright © 2012 John Wiley & Sons, Ltd.)

Background and Aims: Hydration, rupture and exine opening due to the sudden and large expansion of intine are typical of taxoid-type pollen grains. A hemispheric outgrowth external to the exine was observed on Cupressus and Juniperus pollen grains before the intine swelling and exine release. However, the actual existence of this permanent or temporary structure and its precise role in pollen hydration is still being debated. The aim of this paper is to collect information on the actual presence of this peculiar outgrowth on the surface of the Cupressus pollen grain, its structure, composition and function., Methods: Pollen grains of several Cupressus species were observed using various techniques and methodologies, under light and fluorescence microscopy, phase-contrast microscopy, confocal microscopy, scanning electron microscopy, and an environmental scanning electron microscope. Observations were also performed on other species with taxoid-type pollen grains., Key Results: A temporary structure located just above the pore was observed on Cupressus pollen grains, as well as on other taxoid-type pollens. It is hemispheric, layered, and consists of polysaccharides and proteins. The latter are confined to its inner part. Its presence seems to regulate the entrance of water into the grains at the beginning of pollen hydration., Conclusions: The presence of a temporary structure over the pore of taxoid-type pollen grains was confirmed and its structure was resolved using several stains and observation techniques. This structure plays a role in the first phases of pollen hydration.

Chemical polymorphism may contribute to variation in browsing damage by mammalian herbivores. Earlier, we demonstrated that essential oil concentration in juniper, Juniperus communis, was negatively associated with herbivore browsing. The aim of the present study was to characterize the volatile chemical composition of browsed and non-browsed J. communis. By using either gas chromatography with flame ionization detection (GC-FID) or an electronic nose device, we could separate sheep-browsed or non-browsed juniper shrubs by their essential oil pattern and complex odor matrix. The main components of the essential oil from J. communis were monoterpenes. We distinguished three chemotypes, dominated either by α-pinene, sabinene, or δ-3-carene. Shrubs belonging to the α-pinene- or sabinene-dominated groups were browsed, whereas all individuals with the δ-3-carene chemotype were unused by the local herbivores. The electronic nose also separated the browsed and non-browsed shrubs indicating that their odor matrix could guide sheep browsing. Responses of sheep could integrate the post-ingestive effects of plant secondary metabolites with sensory experience that stems from odor-phytotoxin interactions. Chemotype diversity could increase the survival rate in the present population of J. communis as certain shrubs could benefit from relatively better chemical protection against the herbivores.

Foliar carbon isotope discrimination (Δ) is widely used as an integrator of physiological plant responses to environmental change. However, the relationship between foliar Δ and mineral nutrient accumulation is still not well-known. The foliar Δ, K, Ca, Mg, Si and ash contents of S. przewalskii Kom. (SP) and S. chinensis (Lin.) Ant. (SC), two over-winter trees distributed on high altitude plateaux and lower altitude plains, respectively, were measured at monthly intervals over two years under the same growing conditions to examine the genetic and seasonal variation in foliar nutrient concentrations in relation to foliar Δ. The foliar Δ, Mg, K and ash contents were markedly lower in SP than in SC, and the foliar Si content was significantly higher in SP than SC, while the differences in Ca contents between the two Sabina trees were not significant. There was higher foliar Δ in winter than in summer for both Sabina trees. Close negative correlations of foliar Δ with K and Mg content, and significant positive correlations between foliar Δ and Si contents, were observed in SP but not in SC. Thus, higher water-use efficiency of SP than of SC is related to higher Si and lower Mg and K contents that have positive effects on the reduction of transpiration rates or stomatal conductances. The results obtained by the present study will advance the understanding of the adaptive strategies of mineral nutrition and water use in harsh environments., (Copyright © 2011 John Wiley & Sons, Ltd.)

Changes in climate, land management and fire regime have contributed to woody species expansion into grasslands and savannas worldwide. In the USA, Pinus ponderosa P.&C. Lawson and Juniperus virginiana L. are expanding into semiarid grasslands of Nebraska and other regions of the Great Plains. We examined P. ponderosa and J. virginiana seedling response to soil water content, one of the most important limiting factors in semiarid grasslands, to provide insight into their success in the region. Photosynthesis, stomatal conductance, maximum photochemical efficiency of PSII, maximum carboxylation velocity, maximum rate of electron transport, stomatal limitation to photosynthesis, water potential, root-to-shoot ratio, and needle nitrogen content were followed under gradual soil water depletion for 40 days. J. virginiana maintained lower L(s), higher A, g(s), and initial F(v)/F(m), and displayed a more gradual decline in V(cmax) and J(max) with increasing water deficit compared to P. ponderosa. J. virginiana also invested more in roots relative to shoots compared to P. ponderosa. F(v)/F(m) showed high PSII resistance to dehydration in both species. Photoinhibition was observed at approximately 30% of field capacity. Soil water content was a better predictor of A and g(s) than Psi, indicating that there are other growth factors controlling physiological processes under increased water stress. The two species followed different strategies to succeed in semiarid grasslands. P. ponderosa seedlings behaved like a drought-avoidant species with strong stomatal control, while J. virginiana was more of a drought-tolerant species, maintaining physiological activity at lower soil water content. Differences between the studied species and the ecological implications are discussed.

Freshly ground Utah juniper [Juniperus osteosperma (Torr.) Little] bark was given via gavage at a dosage of 2.3 kg per cow twice daily to three pregnant cows starting on day 255 of gestation. All three cows aborted the calves after 4, 5 and 6 days of treatment. A fourth cow was dosed with Utah juniper needles and this cow calved early on day 268 of gestation with complications consistent with pine needle abortion. Chemical analysis of Juniperus osteosperma bark identified the major diterpene acid as the labdane acid known as agathic acid. Agathic acid was measured in the bark at a concentration of 1.5% (dry weight basis). Analysis of sera samples obtained from treated cows found detectable quantities of agathic acid, dihydroagathic acid and tetrahydroagathic acid, which are known serum metabolites of the abortifacient compound isocupressic acid. Based on the high incidence of induced abortion and detection of known metabolites in affected animals, the labdane acid known as agathic acid is considered to be an abortifacient compound in late-term pregnant cattle.

The different abilities of plant species to use ephemeral or permanent water sources strongly affect physiological performance and species coexistence in water-limited ecosystems. In addition to withstanding drought, plants in coastal habitats often have to withstand highly saline soils, an additional ecological stress. Here we tested whether observed competitive abilities and C-water relations of two interacting shrub species from an arid coastal system were more related to differences in root architecture or salinity tolerance. We explored water sources of interacting Juniperus phoenicea Guss. and Pistacia lentiscus L. plants by conducting physiology measurements, including water relations, CO2 exchange, photochemical efficiency, sap osmolality, and water and C isotopes. We also conducted parallel soil analyses that included electrical conductivity, humidity, and water isotopes. During drought, Pistacia shrubs relied primarily on permanent salty groundwater, while isolated Juniperus plants took up the scarce and relatively fresh water stored in upper soil layers. As drought progressed further, the physiological activity of Juniperus plants nearly stopped while Pistacia plants were only slightly affected. Juniperus plants growing with Pistacia had stem-water isotopes that matched Pistacia, unlike values for isolated Juniperus plants. This result suggests that Pistacia shrubs supplied water to nearby Juniperus plants through hydraulic lift. This lifted water, however, did not appear to benefit Juniperus plants, as their physiological performance with co-occurring Pistacia plants was poor, including lower water potentials and rates of photosynthesis than isolated plants. Juniperus was more salt sensitive than Pistacia, which withstood salinity levels similar to that of groundwater. Overall, the different abilities of the two species to use salty water appear to drive the outcome of their interaction, resulting in asymmetric competition where Juniperus is negatively affected by Pistacia. Salt also seems to mediate the interaction between the two species, negating the potential positive effects of an additional water source via hydraulic lift.

Regional, high-resolution mapping of vegetation cover and biomass is central to understanding changes to the terrestrial carbon (C) cycle, especially in the context of C management. The third most extensive vegetation type in the United States is pinyon-juniper (P-J) woodland, yet the spatial patterns of tree cover and aboveground biomass (AGB) of P-J systems are poorly quantified. We developed a synoptic remote-sensing approach to scale up pinyon and juniper projected cover (hereafter "cover") and AGB field observations from plot to regional levels using fractional photosynthetic vegetation (PV) cover derived from airborne imaging spectroscopy and Landsat satellite data. Our results demonstrated strong correlations (P < 0.001) between field cover and airborne PV estimates (r2 = 0.92), and between airborne and satellite PV estimates (r2 = 0.61). Field data also indicated that P-J AGB can be estimated from canopy cover using a unified allometric equation (r2 = 0.69; P < 0.001). Using these multiscale cover-AGB relationships, we developed high-resolution, regional maps of P-J cover and AGB for the western Colorado Plateau. The P-J cover was 27.4% +/- 9.9% (mean +/- SD), and the mean aboveground woody C converted from AGB was 5.2 +/- 2.0 Mg C/ha. Combining our data with the southwest Regional Gap Analysis Program vegetation map, we estimated that total contemporary woody C storage for P-J systems throughout the Colorado Plateau (113 600 km2) is 59.0 +/- 22.7 Tg C. Our results show how multiple remote-sensing observations can be used to map cover and C stocks at high resolution in drylands, and they highlight the role of P-J ecosystems in the North American C budget.

Deposition of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were measured in Loblolly pine needles (Pinus taeda) collected in and around a Linden Chemicals and Plastics (LCP) Superfund Site at Brunswick, Georgia, USA. For the comparison, foliage of eastern red cedar (Juniperus virginiana) was also collected to monitor contaminant levels. This study revealed that concentrations of OCPs, PCBs and PBDEs ranged from 0.75-10, 3.4-15 to 0.05-3, ng/g wet wt, respectively in both plant species. Total OCPs concentrations in pine needles decreased from 10 to 2.3 ng/g; and total PCBs decreased from 28 to 9.3 ng/g between 1997 and 2006. To our knowledge, this is the first report on PBDEs concentrations in pine needles and red cedar foliage samples from the Superfund Site at Brunswick, Georgia, USA.

The impact of browsing on vegetation depends on the relative density and species composition of browsers. Herbivore density and plant damage can be either site-specific or change seasonally and spatially. For juniper (Juniperus communis) forests of a sand dune region in Hungary, it has been assumed that plant damage investigated at different temporal and spatial scales would reflect selective herbivory. The level of juniper damage was tested for a possible correlation with the concentration of plant secondary metabolites (PSMs) in plants and seasonal changes in browsing pressure. Heavily browsed and nonbrowsed junipers were also assumed to differ in their chemical composition, and the spatial distribution of browsing damage within each forest was analyzed to reveal the main browser. Long-term differences in local browsing pressure were also expected and would be reflected in site-specific age distributions of distant juniper populations. The concentrations of PSMs (essential oils) varied significantly among junipers and seasons. Heavily browsed shrubs contained the lowest oil yield; essential oils were highest in shrubs bearing no damage, indicating that PSMs might contribute to reduce browsing in undamaged shrubs. There was a seasonal fluctuation in the yield of essential oil that was lower in the summer period than in other seasons. Gas chromatography (GC) revealed differences in some essential oil components, suggesting that certain chemicals could have contributed to reduced consumption. The consequential long-term changes were reflected in differences in age distribution between distant juniper forests. These results confirm that both the concentration of PSMs and specific compounds of the essential oil may play a role in selective browsing damage by local herbivores.

The nuclear localization of blue-staining flavanols was investigated histochemically throughout microsporogenesis in yellow cypress (Callitropsis nootkatensis (D. Don) Oerst., formerly Cupressus nootkatensis), juniper (Juniperus communis L.) and yew (Taxus baccata L.). During meiotic development, both the cytoplasm and nuclei of microspores of all species contained varying amounts of flavanols; however, the flavanols were largely confined to the nuclei in microspores just released from tetrads. Quantification by HPLC analysis indicated that, in all species, catechin and epicatechin were the dominant nuclear flavanols. At the early free microspore stage, the nuclear flavanols were barely detectable in all species, but they increased fivefold on incubation in the presence of 0.1 mM benzylaminopurine (BA) or zeatin. Histochemical studies revealed that, in addition to non-fluorescing flavanols, microspores contained yellow-fluorescing flavonoids, which yielded a distinct HPLC flavonoid profile for each species. In yellow cypress, the hydrolyzed flavonoids were identified as quercetin, apigenin, kaempferol and luteolin, whereas only quercetin and myricetin were found in microspores of juniper and in anthers of yew. Application of a UV-VIS titration technique revealed that the aglycone quercetin seems to interact more strongly with histone H3 than either glycoside rutin or kaempferol.

A large proportion of rainfall in dryland ecosystems is intercepted by plant foliage and is generally assumed to evaporate to the atmosphere or drip onto the soil surface without being absorbed. We demonstrate foliar absorption of intercepted rainfall in a widely distributed, continental dryland, woody-plant genus: Juniperus. We observed substantial improvement in plant water status, exceeding 1.0 MPa water potential for drought-stressed plants, following precipitation on an experimental plot that excluded soil water infiltration. Experiments that wetted shoots with unlabeled and with isotopically labeled water confirmed that water potential responded substantially to foliar wetting, that these responses were not attributable to re-equilibration with other portions of the xylem, and that magnitude of response increased with water stress. Foliar absorption is not included in most ecological, hydrological, and atmospheric models; has implications for interpreting plant isotopic signatures; and not only supplements water acquisition associated with increases in soil moisture that follow large or repeated precipitation events, but also enables plants to bypass soil water uptake and benefit from the majority of precipitation events, which wet foliage but do not increase soil moisture substantially. Foliar absorption of intercepted water could be more important than previously appreciated, especially during drought when water stress is greatest.

Previous studies of pinyon-juniper woodlands show that Pinus edulis Engelm. makes better use of soil water from summer precipitation pulses than does co-occurring Juniperus osteosperma (Torr.) Little. To investigate the basis of this difference, we examined seasonal variation in cavitation and hydraulic conductance. Pinus edulis remained isohydric over the growing season. Minimum water potentials never fell below -2.3 MPa, and the extent of xylem cavitation remained near constant during the dry season. In contrast, J. osteosperma was anisohydric, reaching water potentials as low as -6.9 MPa, and experiencing progressively greater xylem cavitation as the dry season progressed despite having more cavitation-resistant xylem than P. edulis. We conducted an irrigation experiment to observe the responses of the study species to a summer pulse of water. Although sap flow increased in both species in response to the 25-mm irrigation pulse, only J. osteosperma responded to the 10-mm pulse. This was inconsistent with the response of P. edulis to light rain events and may have been due to a difference in the distribution of irrigation water and rain water between the under- and between-canopy areas. Whole-plant conductance increased following the 25-mm irrigation in P. edulis but remained constant in J. osteosperma. We hypothesized that this difference was caused, in part, by differential refilling of embolized xylem. Area specific hydraulic conductivity was 66% higher in roots of irrigated P. edulis trees relative to roots of control trees 3 days after the 25-mm irrigation (t = 2.14, P = 0.02, df = 16). There was no change in hydraulic conductivity of the roots of J. osteosperma or in the stems of either species. Our results indicate that the response to an irrigation pulse in P. edulis depended on cavitation avoidance in stems and the reversal of cavitation in roots, resulting in increased whole-plant conductance and water uptake. In contrast, J. osteosperma failed to exploit light summer rain events but was able to extract deep soil water at low water potentials.

Background and Aims: The pollination drop is a liquid secretion produced by the ovule and exposed outside the micropyle. In many gymnosperms, pollen lands on the surface of the pollination drop, rehydrates and enters the ovule as the drop retracts. The objective of this work was to study the formation of the pollination drop in Juniperus communis, its carbohydrate composition and the response to deposition of conspecific pollen, foreign pollen and other particulate material, in an attempt to clarify the mechanism of pollination drop retraction., Methods: Branches with female cones close to pollination drop secretion were collected. On the first day of pollination drop exposure, an eyelash mounted on a wooden stick with paraffin was used to collect pollen or silica gel particles, which were then deposited by contact with the drop. Volume changes in pollination drops were measured by using a stereomicroscope with a micrometer eyepiece 3 h after deposition. The volume of non-pollinated control drops was also recorded. On the first day of secretion, drops were also collected for sugar analysis by high-performance liquid chromatography., Key Results: The pollination drop persisted for about 12 d if not pollinated, and formed again after removal for up to four consecutive days. After pollination with viable conspecific pollen, the drop retracted quickly and did not form again. Partial withdrawal occurred after deposition of other biological and non-biological material. Fructose was the dominant sugar; glucose was also present but at a much lower percentage., Conclusions: Sugar analysis confirmed the general trend of fructose dominance in gymnosperm pollination drops. Complete pollination drop withdrawal appears to be triggered by a biochemical mechanism resulting from interaction between pollen and drop constituents. The results of particle deposition suggest the existence of a non-specific, particle-size-dependent mechanism that induces partial pollination drop withdrawal. These results suggest that the non-specific response may decrease the probability of pollen landing on the drop, reducing pollination efficiency.

Eastern redcedar is widespread in the US and produces significant amount of biomass. Open-grown trees invade abandoned fields and compete with valuable forage species in pastures and rangelands. Value-added product development from redcedar is vital for management of eastern redcedar. Cedarwood oil is a valuable component which can be used for further value-added product development. This study examined the effect of age on the distribution of oil in redcedar tree segments. Trunks of eastern redcedar (Juniperus virginiana L.) trees at different stages of growth (26-63 years old) were divided into three sections (top, center and lower). Each section was fractionated separately into bark, heartwood and sapwood segments. Heartwood and sapwood samples from each tree section were analyzed for oil content and composition. A hydrodistillation method was used for oil extraction. Volatile components of tree segments were examined by using a Gas Chromatograph-headspace analysis technique. The heartwood of eastern redcedar contained significantly higher oil than sapwood. Older trees had more oil in the heartwood than younger trees. Both redcedar bark and leaves contained significantly lower oil content than the cedarwood. There were also significant differences in the oil composition of bark, leaves and wood fractions. Cedarwood oil extraction may benefit from prior separation of tree segments prior to oil extraction. However, the economic feasibility of separation prior to an extraction process needs to be further studied. Required extra capital investment and operating costs need to be examined, as well as whether sapwood is worth processing.

In water-limited environments of the intermountain region of North America, summer precipitation may play a role in the structure and function of aridland communities and ecosystems. This study examined the potential reliance on summer precipitation of two widespread, coexisting woody species in the southwestern United States, Pinus edulis Englmn. (Colorado piñon) and Juniperus osteosperma (Torr) Little (Utah juniper). The current distributions of P. edulis and J. osteosperma are highly suggestive of different dependencies on summer rainfall. We hypothesized that P. edulis was dependent on summer precipitation, utilizing summer precipitation even during extremely dry summers, whereas J. osteosperma was not dependent, using summer precipitation only when amounts were above some minimum threshold. Using sap flux and stable isotopic methods to assess seasonal water sources and water use efficiency, we examined the response of these two species to seasonal variations in moisture at a site located near the northern limits of the North American monsoon. Both sap flux and isotopic results indicated that P. edulis was responsive to summer rain, while J. osteosperma was not. Following summer rain events, sap flux density increased in P. edulis for several days, but not in J. osteosperma. Isotopic evidence indicated that P. edulis took up summer-derived moisture to a greater extent than J. osteosperma. Values of the natural abundance stable isotope ratio of carbon of leaf soluble carbohydrates increased over the summer for P. edulis, indicative of assimilation at higher water use efficiency, but were invariant for J. osteosperma. Our results supported the hypothesis that P. edulis and J. osteosperma are differentially sensitive to summer precipitation and are discussed in the light of potential changes in the seasonality of precipitation associated with climate change.

Arsenic concentrations were measured in annual rings, pith, bark, and leaves of five tree species (four genera) from a site highly contaminated with As in Vineland, New Jersey, and two nearby uncontaminated areas. The highest As concentrations were found in bark (0.68+/-0.89 mg/kg, n=16) and leaves (1.9+/-1.8 mg/kg, n=4) from the contaminated area. Tree-ring As levels from the contaminated area (0.28+/-0.15 mg/kg, n=32) were low but still considerably higher than those from the control areas (0.06+/-0.06 mg/kg, n=30). There is a generally positive relationship between soil and tree-ring As levels. The overall low uptake of As by trees contrasts with that of P, a chemical analog for As(V) in aerated soils. Much higher P concentration in sapwood than in heartwood indicates that P is exported into more recently formed wood during the conversion from sapwood to heartwood; this again is drastically different than the behavior of As which is present in sapwood and heartwood at comparable levels. Variable sapwood As concentrations observed in detailed radial profiles of tree-ring chemistry of a pine and an oak from the contaminated site suggest that As is most likely transported among multiple rings within the sapwood. Therefore, tree species for which sapwood is thin (e.g., oak as in this study) should be preferred for reconstructing the history of contamination of a site. Due to the possibility of lateral translocation between growth rings, further studies are necessary to understand within-tree As transport and storage before dendrochemistry can be confidently accepted for such applications.

Amyotrophic lateral sclerosis (ALS) is characterized by degeneration of motor neurons. We tested the hypothesis that proteomic analysis will identify protein biomarkers that provide insight into disease pathogenesis and are diagnostically useful. To identify ALS specific biomarkers, we compared the proteomic profile of cerebrospinal fluid (CSF) from ALS and control subjects using surface-enhanced laser desorption/ionization-time of flight mass spectrometry (SELDI-TOF-MS). We identified 30 mass ion peaks with statistically significant (p < 0.01) differences between control and ALS subjects. Initial analysis with a rule-learning algorithm yielded biomarker panels with diagnostic predictive value as subsequently assessed using an independent set of coded test subjects. Three biomarkers were identified that are either decreased (transthyretin, cystatin C) or increased (carboxy-terminal fragment of neuroendocrine protein 7B2) in ALS CSF. We validated the SELDI-TOF-MS results for transthyretin and cystatin C by immunoblot and immunohistochemistry using commercially available antibodies. These findings identify a panel of CSF protein biomarkers for ALS.

Peanut-like 1 (PNUTL1) is a septin gene which is expressed at high levels in human brain. There it plays a role in the process of membrane fusion during exocytosis by interacting with syntaxin and synaptophysin. As the secretory apparatus of pancreatic islet cells closely resembles that of neurons, we decided to study the expression of PNUTL1 in the human endocrine pancreas, both in normal islets and in pancreatic endocrine tumors (PETs). Normal pancreatic tissue, purified islets, 11 PETs and two cell lines were used to evaluate the presence of PNUTL1 by RT-PCR and Western blot. The expression of the PNUTL1 protein was also evaluated by immunohistochemistry on normal pancreas, additional 26 PETs, eight pancreatic adenocarcinomas, one mixed endocrine-exocrine pancreatic neoplasm, a specimen of solid papillary pseudomucinous tumor, an adult islet cell hyperplasia and a case of neonatal nesidioblastosis. In addition, a tissue array (LandMark High Density Cancer Tissue MicroArray) comprising 280 various tumor and matched normal specimens was utilized. In PETs, the expression of pancreatic hormones, chromogranin-A, synaptophysin and Ki-67 were also evaluated. In the normal pancreas PNUTL1 expression is almost exclusively confined to the islet cells, weak expression was occasionally seen in some acinar cells, while immunoreactivity was completely absent in the ductal epithelia. PNUTL1 expression is maintained at similar high levels in hyperplastic and neoplastic islet cells, but this did not correlate with any of the clinicopathological data nor with proliferation status in PETs. Weak immunoreactivity was also noted in a proportion of exocrine neoplasms. Our findings describe for the first time the high expression levels of PNUTL1 in human pancreatic endocrine cells that suggests a similar role of this protein in islet cells to that demonstrated in neuronal tissues, and warrants further functional studies of this protein., (Copyright (c) 2005 S. Karger AG, Basel.)

In coastal environments plants have to cope with various water sources: rainwater, water table, seawater, and mixtures. These are usually characterized by different isotopic signatures ( (18)O/ (16)O and D/H ratios). Xylem water reflects the isotopic compositions of the water sources. Additionally, water-use efficiency (WUE) can be assessed with carbon isotope discrimination (Delta) analyses. Gas exchange, Delta of leaf dry matter, and isotopic composition (delta (18)O) of xylem water were measured from June to August 2001 in herbaceous perennials of mobile dunes (Ammophila littoralis, Elymus farctus) and sclerophyllous shrubs and climbers (Arbutus unedo, Pistacia lentiscus, Phillyrea angustifolia, Qercus ilex, Juniperus oxycedrus, Smilax aspera) of consolidated dunes. Assimilation rates were rather low and did not show clear seasonal patterns, possibly due to limited precipitation and generally low values of stomatal conductance. The lowest values were shown in S. aspera. Different physiological patterns were found, on the basis of delta (18)O and Delta analyses. Values of delta (18)O of xylem water of phanerophytes were remarkably constant and matched those of the water table, indicating dependence on a reliable water source; values of Delta were relatively high, indicating low intrinsic WUE, with the exception of J. oxycedrus. Surprisingly, very high delta (18)O values were found for the xylem water from S. aspera in August. This suggests retrodiffusion of leaf water to xylem sap in the stem or direct uptake of water by leaves or stems, owing to dew or fog occurrence. Low Delta values indicated high WUE in S. aspera. Contrasting strategies were shown by the species of mobile dunes: E. farctus relied on superficial water and exhibited low WUE, accordingly to its therophyte-like vegetative cycle; on the contrary, A. littoralis used deeper water sources, showing higher WUE in relation to its long-lasting vegetative habit.