Mercury bioaccumulation pathways in tusk (Brosme brosme) from Sognefjord, Norway: Insights from C and N isotopes.

Seafood is the main source of methylmercury (MeHg) exposure for humans and elevated total mercury (Hg) concentrations have been reported in marine fish from Norwegian fjords compared with offshore areas. Hg in tusk fillets (n = 201) and liver samples (n = 177) were measured in individuals from different habitats including offshore, coastal area, outer and inner Sognefjord. Specifically, the effects of habitat, energy sources and trophic complexity on Hg bioaccumulation pathways in tusk (Brosme brosme) were investigated using stable isotopes of carbon (δ13C) and nitrogen (δ15N). The concentrations of Hg in tusk increased from offshore towards inner Sognefjord. While Hg concentrations in sediment were at background levels, tusk fillet samples from 7 of 8 sites in Sognefjord had higher Hg levels than the maximum level set by European Union. Based on these findings, human consumption advice for tusk from Sognefjord was issued by the Norwegian Food Safety Authority. δ13C values in tusk successfully discriminated individuals from different habitats and were positively correlated to Hg concentrations in tusk across individuals, sites and habitats, outlining the potential importance of terrestrial carbon and most likely the atmospheric deposition of Hg from the catchment to the overall Hg bioaccumulation and exposure regime in tusk. Additionally, we postulate that the effects of terrestrial carbon sources increased towards inner Sognefjord and likely influenced Hg bioavailability throughout the food web. In contrast, δ15N values were patchy throughout the fjord system and although trophic position explained some of the Hg variation between individual fish, it was not correlated with Hg variation across sites and habitats. Our results suggest that tusk can accumulate high levels of Hg in fjord ecosystems and that catchment runoff is likely an important driver of Hg bioaccumulation in this species.

Ten years of barcoding at the African Centre for DNA Barcoding.

The African Centre for DNA Barcoding (ACDB) was established in 2005 as part of a global initiative to accurately and rapidly survey biodiversity using short DNA sequences. The mitochondrial cytochrome c oxidase 1 gene (CO1) was rapidly adopted as the de facto barcode for animals. Following the evaluation of several candidate loci for plants, the Plant Working Group of the Consortium for the Barcoding of Life in 2009 recommended that two plastid genes, rbcLa and matK, be adopted as core DNA barcodes for terrestrial plants. To date, numerous studies continue to test the discriminatory power of these markers across various plant lineages. Over the past decade, we at the ACDB have used these core DNA barcodes to generate a barcode library for southern Africa. To date, the ACDB has contributed more than 21 000 plant barcodes and over 3000 CO1 barcodes for animals to the Barcode of Life Database (BOLD). Building upon this effort, we at the ACDB have addressed questions related to community assembly, biogeography, phylogenetic diversification, and invasion biology. Collectively, our work demonstrates the diverse applications of DNA barcoding in ecology, systematics, evolutionary biology, and conservation.

Exposing the illegal trade in cycad species (Cycadophyta: Encephalartos) at two traditional medicine markets in South Africa using DNA barcoding.

Species in the cycad genus Encephalartos are listed in CITES Appendix I and as Threatened or Protected Species in terms of South Africa's National Environmental Management: Biodiversity Act (NEM:BA) of 2004. Despite regulations, illegal plant harvesting for medicinal trade has continued in South Africa and resulted in declines in cycad populations and even complete loss of sub-populations. Encephalartos is traded at traditional medicine markets in South Africa in the form of bark strips and stem sections; thus, determining the species traded presents a major challenge due to a lack of characteristic plant parts. Here, a case study is presented on the use of DNA barcoding to identify cycads sold at the Faraday and Warwick traditional medicine markets in Johannesburg and Durban, respectively. Market samples were sequenced for the core DNA barcodes (rbcLa and matK) as well as two additional regions: nrITS and trnH-psbA. The barcoding database for cycads at the University of Johannesburg was utilized to assign query samples to known species. Three approaches were followed: tree-based, similarity-based, and character-based (BRONX) methods. Market samples identified were Encephalartos ferox (Near Threatened), Encephalartos lebomboensis (Endangered), Encephalartos natalensis (Near Threatened), Encephalartos senticosus (Vulnerable), and Encephalartos villosus (Least Concern). Results from this study are crucial for making appropriate assessments and decisions on how to manage these markets.

Overweight and the feline gut microbiome - a pilot study.

Compared with lean humans, the gut microbiota is altered in the obese. Whether these changes are due to an obesogenic diet, and whether the microbiota contributes to adiposity is currently discussed. In the cat population, where obesity is also prevalent, gut microbiome changes associated with obesity have not been studied. Consequently, the aim of this study was to compare the gut microbiota of lean cats, with that of overweight and obese cats. Seventy-seven rescue-shelter cats housed for ≥3 consecutive days were included in the study. Faecal samples were obtained by rectal swab and, when available, by a paired litter box sample. Body condition was assessed using a 9-point scoring system. DNA was extracted, and the 16S rRNA gene was amplified with a high-throughput quantitative real-time PCR chip. Overweight and obese cats had a significantly different gut microbiota compared to lean cats (p < 0.05), but this finding could not be linked to differences in specific bacterial groups. The rectal samples obtained higher DNA concentration than litter box samples (p < 0.0001). In conclusion, overweight and obese cats seem to have an altered gut microbiome as compared to lean cats.

Fungal Planet description sheets: 214-280.

Novel species of microfungi described in the present study include the following from South Africa: Cercosporella dolichandrae from Dolichandra unguiscati, Seiridium podocarpi from Podocarpus latifolius, Pseudocercospora parapseudarthriae from Pseudarthria hookeri, Neodevriesia coryneliae from Corynelia uberata on leaves of Afrocarpus falcatus, Ramichloridium eucleae from Euclea undulata and Stachybotrys aloeticola from Aloe sp. (South Africa), as novel member of the Stachybotriaceae fam. nov. Several species were also described from Zambia, and these include Chaetomella zambiensis on unknown Fabaceae, Schizoparme pseudogranati from Terminalia stuhlmannii, Diaporthe isoberliniae from Isoberlinia angolensis, Peyronellaea combreti from Combretum mossambiciensis, Zasmidium rothmanniae and Phaeococcomyces rothmanniae from Rothmannia engleriana, Diaporthe vangueriae from Vangueria infausta and Diaporthe parapterocarpi from Pterocarpus brenanii. Novel species from the Netherlands include: Stagonospora trichophoricola, Keissleriella trichophoricola and Dinemasporium trichophoricola from Trichophorum cespitosum, Phaeosphaeria poae, Keissleriella poagena, Phaeosphaeria poagena, Parastagonospora poagena and Pyrenochaetopsis poae from Poa sp., Septoriella oudemansii from Phragmites australis and Dendryphion europaeum from Hedera helix (Germany) and Heracleum sphondylium (the Netherlands). Novel species from Australia include: Anungitea eucalyptorum from Eucalyptus leaf litter, Beltraniopsis neolitseae and Acrodontium neolitseae from Neolitsea australiensis, Beltraniella endiandrae from Endiandra introrsa, Phaeophleospora parsoniae from Parsonia straminea, Penicillifer martinii from Cynodon dactylon, Ochroconis macrozamiae from Macrozamia leaf litter, Triposporium cycadicola, Circinotrichum cycadis, Cladosporium cycadicola and Acrocalymma cycadis from Cycas spp. Furthermore, Vermiculariopsiella dichapetali is described from Dichapetalum rhodesicum (Botswana), Ophiognomonia acadiensis from Picea rubens (Canada), Setophoma vernoniae from Vernonia polyanthes and Penicillium restingae from soil (Brazil), Pseudolachnella guaviyunis from Myrcianthes pungens (Uruguay) and Pseudocercospora neriicola from Nerium oleander (Italy). Novelties from Spain include: Dendryphiella eucalyptorum from Eucalyptus globulus, Conioscypha minutispora from dead wood, Diplogelasinospora moalensis and Pseudoneurospora canariensis from soil and Inocybe lanatopurpurea from reforested woodland of Pinus spp. Novelties from France include: Kellermania triseptata from Agave angustifolia, Zetiasplozna acaciae from Acacia melanoxylon, Pyrenochaeta pinicola from Pinus sp. and Pseudonectria rusci from Ruscus aculeatus. New species from China include: Dematiocladium celtidicola from Celtis bungeana, Beltrania pseudorhombica, Chaetopsina beijingensis and Toxicocladosporium pini from Pinus spp. and Setophaeosphaeria badalingensis from Hemerocallis fulva. Novel genera of Ascomycetes include Alfaria from Cyperus esculentus (Spain), Rinaldiella from a contaminated human lesion (Georgia), Hyalocladosporiella from Tectona grandis (Brazil), Pseudoacremonium from Saccharum spontaneum and Melnikomyces from leaf litter (Vietnam), Annellosympodiella from Juniperus procera (Ethiopia), Neoceratosperma from Eucalyptus leaves (Thailand), Ramopenidiella from Cycas calcicola (Australia), Cephalotrichiella from air in the Netherlands, Neocamarosporium from Mesembryanthemum sp. and Acervuloseptoria from Ziziphus mucronata (South Africa) and Setophaeosphaeria from Hemerocallis fulva (China). Several novel combinations are also introduced, namely for Phaeosphaeria setosa as Setophaeosphaeria setosa, Phoma heteroderae as Peyronellaea heteroderae and Phyllosticta maydis as Peyronellaea maydis. Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.

Fungal Planet description sheets: 281-319.

Novel species of fungi described in the present study include the following from South Africa: Alanphillipsia aloeicola from Aloe sp., Arxiella dolichandrae from Dolichandra unguiscati, Ganoderma austroafricanum from Jacaranda mimosifolia, Phacidiella podocarpi and Phaeosphaeria podocarpi from Podocarpus latifolius, Phyllosticta mimusopisicola from Mimusops zeyheri and Sphaerulina pelargonii from Pelargonium sp. Furthermore, Barssia maroccana is described from Cedrus atlantica (Morocco), Codinaea pini from Pinus patula (Uganda), Crucellisporiopsis marquesiae from Marquesia acuminata (Zambia), Dinemasporium ipomoeae from Ipomoea pes-caprae (Vietnam), Diaporthe phragmitis from Phragmites australis (China), Marasmius vladimirii from leaf litter (India), Melanconium hedericola from Hedera helix (Spain), Pluteus albotomentosus and Pluteus extremiorientalis from a mixed forest (Russia), Rachicladosporium eucalypti from Eucalyptus globulus (Ethiopia), Sistotrema epiphyllum from dead leaves of Fagus sylvatica in a forest (The Netherlands), Stagonospora chrysopyla from Scirpus microcarpus (USA) and Trichomerium dioscoreae from Dioscorea sp. (Japan). Novel species from Australia include: Corynespora endiandrae from Endiandra introrsa, Gonatophragmium triuniae from Triunia youngiana, Penicillium coccotrypicola from Archontophoenix cunninghamiana and Phytophthora moyootj from soil. Novelties from Iran include Neocamarosporium chichastianum from soil and Seimatosporium pistaciae from Pistacia vera. Xenosonderhenia eucalypti and Zasmidium eucalyptigenum are newly described from Eucalyptus urophylla in Indonesia. Diaporthe acaciarum and Roussoella acacia are newly described from Acacia tortilis in Tanzania. New species from Italy include Comoclathris spartii from Spartium junceum and Phoma tamaricicola from Tamarix gallica. Novel genera include (Ascomycetes): Acremoniopsis from forest soil and Collarina from water sediments (Spain), Phellinocrescentia from a Phellinus sp. (French Guiana), Neobambusicola from Strelitzia nicolai (South Africa), Neocladophialophora from Quercus robur (Germany), Neophysalospora from Corymbia henryi (Mozambique) and Xenophaeosphaeria from Grewia sp. (Tanzania). Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.

Fungal Planet description sheets: 154-213.

Novel species of microfungi described in the present study include the following from South Africa: Camarosporium aloes, Phaeococcomyces aloes and Phoma aloes from Aloe, C. psoraleae, Diaporthe psoraleae and D. psoraleae-pinnatae from Psoralea, Colletotrichum euphorbiae from Euphorbia, Coniothyrium prosopidis and Peyronellaea prosopidis from Prosopis, Diaporthe cassines from Cassine, D. diospyricola from Diospyros, Diaporthe maytenicola from Maytenus, Harknessia proteae from Protea, Neofusicoccum ursorum and N. cryptoaustrale from Eucalyptus, Ochrocladosporium adansoniae from Adansonia, Pilidium pseudoconcavum from Greyia radlkoferi, Stagonospora pseudopaludosa from Phragmites and Toxicocladosporium ficiniae from Ficinia. Several species were also described from Thailand, namely: Chaetopsina pini and C. pinicola from Pinus spp., Myrmecridium thailandicum from reed litter, Passalora pseudotithoniae from Tithonia, Pallidocercospora ventilago from Ventilago, Pyricularia bothriochloae from Bothriochloa and Sphaerulina rhododendricola from Rhododendron. Novelties from Spain include Cladophialophora multiseptata, Knufia tsunedae and Pleuroascus rectipilus from soil and Cyphellophora catalaunica from river sediments. Species from the USA include Bipolaris drechsleri from Microstegium, Calonectria blephiliae from Blephilia, Kellermania macrospora (epitype) and K. pseudoyuccigena from Yucca. Three new species are described from Mexico, namely Neophaeosphaeria agaves and K. agaves from Agave and Phytophthora ipomoeae from Ipomoea. Other African species include Calonectria mossambicensis from Eucalyptus (Mozambique), Harzia cameroonensis from an unknown creeper (Cameroon), Mastigosporella anisophylleae from Anisophyllea (Zambia) and Teratosphaeria terminaliae from Terminalia (Zimbabwe). Species from Europe include Auxarthron longisporum from forest soil (Portugal), Discosia pseudoartocreas from Tilia (Austria), Paraconiothyrium polonense and P. lycopodinum from Lycopodium (Poland) and Stachybotrys oleronensis from Iris (France). Two species of Chrysosporium are described from Antarctica, namely C. magnasporum and C. oceanitesii. Finally, Licea xanthospora is described from Australia, Hypochnicium huinayensis from Chile and Custingophora blanchettei from Uruguay. Novel genera of Ascomycetes include Neomycosphaerella from Pseudopentameris macrantha (South Africa), and Paramycosphaerella from Brachystegia sp. (Zimbabwe). Novel hyphomycete genera include Pseudocatenomycopsis from Rothmannia (Zambia), Neopseudocercospora from Terminalia (Zambia) and Neodeightoniella from Phragmites (South Africa), while Dimorphiopsis from Brachystegia (Zambia) represents a novel coelomycetous genus. Furthermore, Alanphillipsia is introduced as a new genus in the Botryosphaeriaceae with four species, A. aloes, A. aloeigena and A. aloetica from Aloe spp. and A. euphorbiae from Euphorbia sp. (South Africa). A new combination is also proposed for Brachysporium torulosum (Deightoniella black tip of banana) as Corynespora torulosa. Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.

Endothelial progenitors encapsulated in bioartificial niches are insulated from systemic cytotoxicity and are angiogenesis competent.

Intrinsic stem cells (SC) participate in tissue remodeling and regeneration in various diseases and following toxic insults. Failure of tissue regeneration is in part attributed to lack of SC protection from toxic stress of noxious stimuli, thus prompting intense research efforts to develop strategies for SC protection and functional preservation for in vivo delivery. One strategy is creation of artificial SC niches in an attempt to mimic the requirements of endogenous SC niches by generating scaffolds with properties of extracellular matrix. Here, we investigated the use of hyaluronic acid (HA) hydrogels as an artificial SC niche and examined regenerative capabilities of encapsulated embryonic endothelial progenitor cells (eEPC) in three different in vivo models. Hydrogel-encapsulated eEPC demonstrated improved resistance to toxic insult (adriamycin) in vitro, thus prompting in vivo studies. Implantation of HA hydrogels containing eEPC to mice with adriamycin nephropathy or renal ischemia resulted in eEPC mobilization to injured kidneys (and to a lesser extent to the spleen) and improvement of renal function, which was equal or superior to adoptively transferred EPC by intravenous infusion. In mice with hindlimb ischemia, EPC encapsulated in HA hydrogels dramatically accelerated the recovery of collateral circulation with the efficacy superior to intravenous infusion of EPC. In conclusion, HA hydrogels protect eEPC against adriamycin cytotoxicity and implantation of eEPC encapsulated in HA hydrogels supports renal regeneration in ischemic and cytotoxic (adriamycin) nephropathy and neovascularization of ischemic hindlimb, thus establishing their functional competence and superior capabilities to deliver stem cells stored in and released from this bioartificial niche.

Watershed nitrogen and mercury geochemical fluxes integrate landscape factors in long-term research watersheds at Acadia National Park, Maine, USA.

This paper is an overview of this special issue devoted to watershed research in Acadia National Park (Acadia NP). The papers address components of an integrated research program on two upland watersheds at Acadia NP, USA (44 degrees 20' N latitude; 68 degrees 15' E longitude). These watersheds were instrumented in 1998 to provide a long-term foundation for regional ecological and watershed research. The research was initiated as part of EPA/NPS PRIMENet (Park Research and Intensive Monitoring of Ecosystems Network), a system of UV-monitoring stations and long-term watershed research sites located in US national parks. The initial goals at Acadia NP were to address research questions about mercury, acid rain, and nitrogen saturation developed from prior research. The project design was based on natural differences in forests and soils induced by an intense wildfire in one watershed in 1947. There is no evidence of fire in the reference watershed for several hundred years. We are testing hypotheses about controls on surface water chemistry, and bioavailability of contaminants in the contrasting watersheds. The unburned 47-ha Hadlock Brook watershed is 70% spruce-fir mature conifer forest. In contrast, burned 32-ha Cadillac Brook watershed, 4 km northeast of the Hadlock watershed, is 20% regenerating mixed northern hardwoods and 60% shrub/rocky balds. Differences in atmospheric deposition are controlled primarily by forest stand composition and age. The watersheds are gauged and have water chemistry stations at 122 m (Cadillac) and 137 m (Hadlock); watershed maximum elevations are 468 and 380 m, respectively. The stream water chemistry patterns reflect, in part, the legacy of the intense fire, which, in turn, controls differences in forest vegetation and soil characteristics. These factors result in higher nitrogen and mercury flux from the unburned watershed, reflecting differences in atmospheric deposition, contrasting ecosystem pools of nitrogen and mercury, and inferred differences in internal cycling and bioavailabilty.

High expression of markers of apoptosis in Langerhans cell histiocytosis.

AIMS: Langerhans cell histiocytosis is a rare disease with clonal proliferation of dendritic histiocytes, occurring most frequently in infancy and early childhood. In the localized form (single system), the disease is self-limiting, but in the cases of multisystem disease a third of the patients develop organ dysfunction. In these cases the prognosis is poor. Our objective has been to study the immunohistochemical expression of Fas and Fas-ligand (Fas-L) in order to determine whether the level of expression of these proteins could predict the outcome of the disease. We also wanted to determine the number of apoptotic cells to compare with the expression of Fas and Fas-L. METHODS AND RESULTS: We analysed the expression of Fas and Fas-L in 76 infiltrates from 49 paediatric patients with Langerhans cell histiocytosis. We also compared the results with the expression of the tumour suppressor protein p53 and the number of cells in apoptosis detected with TUNEL. Langerhans cell histiocytosis cells showed strong expression of p53 and in some cases co-expression of Fas and Fas-L. The expression of Fas-L was significantly higher in infiltrates from patients with single-system disease. The actual number of pathological Langerhans cells in apoptosis as estimated by TUNEL was low. CONCLUSIONS: The low number of TUNEL-reactive cells can be explained by the rapid turnover of apoptotic cells in the tissue, not leaving the apoptotic cells long enough in the tissue to be detected. The co-expression of Fas and Fas-L in some Langerhans cells can lead to an autocrine apoptotic shortcut, mediating the death of the double-positive cells. Our findings suggest that apoptosis mediated through the Fas/Fas-L pathway may contribute to the spontaneous regression of lesions in single-system disease. A delicate balance between autocrine death and survival of Langerhans cells may have been disturbed in patients with multisystem lesions.

A review of the use of allozyme electrophoresis in plant systematics.

The role of electrophoretic data is discussed as it applies to plant taxonomy and systematic studies. Nei's (Am. Nat. 106 (1972) 283-292; Genetics 89 (1978) 583-590) genetic distances calculated for a large number of populations, species and genera were taken from published data. The relation between Nei's genetic identity measures and taxonomic rank (populations, species and genera) are shown graphically. The graphs obtained in this way (from 3021 pairs of plant taxa) differ substantially from previous graphs published by Thorpe (Ann. Rev. Ecol. Syst. 13 (1982) 139-168; in: G.S. Oxford, D. Rollinson (Eds.), Protein Polymorphism: Adaptive and Taxonomic Significance, Academic Press, London, 1983, pp. 131-152) and Thorpe and Solé-Cava (Zool. Scripta 23 (1994) 3-18). These authors suggested that the divergence between the different taxonomic ranks is roughly similar across a wide range of taxa. The latter was based on values for 2664 (Thorpe, 1982) and 8060 (Thorpe, 1983) pairs of animal and plant taxa, but the plant data contributed little to the total. For any given taxonomic rank, we found that plants are genetically more closely related than animals (possibly with the exception of birds). This result is important because the empirical relationships of genetic distance measures, to different levels of taxonomic separation, is often used for distinguishing and identifying cryptic or sibling species where conventional methods are unable to resolve systematic problems.

Allozyme and DNA sequence comparisons of nine species of Encephalartos (Zamiaceae).

Phylogenetic relationships between Encephalartos altensteinii Lehmann, E. arenarius R.A. Dyer, E. horridus (Jacquin) Lehmann, E. latifrons Lehmann, E. lehmannii Lehmann, E. longifolius (Jacquin) Lehmann, E. princeps R.A. Dyer and E. trispinosus (Hooker) R.A. Dyer were studied, using E. ferox Bertoloni f. as outgroup. Three continuous and one discontinuous buffer systems were used and gene products of 14 enzyme coding loci were examined by horizontal starch gel-electrophoresis. Genetic variation was studied in a cultivated population of E. lehmannii and the average heterozygosity value for this population is 13.5%, which falls within the range reported for other cycad species. Fixed allele differences between the species studied was not found at any of the loci studied, which suggest that these species are closely related. DNA sequence analysis of rbcL and ITS 1 & 2 genes (1428 and 895 basepairs, respectively) confirmed the close genetic relationships between these taxa. According to ITS and rbcL sequences E. altensteinii and E. princeps are sibling taxa which form a sister group to E. arenarius, E. horridus, E. latifrons, E. lehmannii, E. longifolius, and E. trispinosus. The genetic distances between both groups were 0.12-0.47% for ITS and 0.08-0.16% for rbcL DNA. The results indicate recent (probably pleistocenic) speciation for this group of cycads, and the relationships are discussed with reference to affinities based on morphology and distribution.

Preliminary experience in the treatment of choroidal melanoma with gamma knife radiosurgery.

OBJECT: The authors report their early results from an ongoing experience treating patients with choroidal melanoma by using gamma knife radiosurgery (GKS). METHODS: Between September 1998 and March 2000, 11 patients were treated for choroidal melanoma. Treatment was facilitated with specialized frame placement. Eye immobilization was accomplished with supra- and infraorbital nerve block and tethering sutures to the periorbital tissue. Magnetic resonance imaging was performed to localize the tumor for treatment planning. Plugging patterns were used to steer fall-off radiation away from the fovea, optic nerve, or lens. Tumor volume, tumor location relative to critical structures, and dose to critical structures were determined using GammaPlan. Tumor response was determined using ultrasonography. Toxicity was determined by clinical assessment, visual acuity testing, and ophthalmoscopy. All 11 patients successfully completed the treatment. In every case, 40 Gy was prescribed to the 50% isodose, which completely encompassed all visible tumor. Tumor height ranged from 2.9 to 7 mm. The tumor diameter ranged from 6 to 13 mm. The range of follow up was 2 to 19 months. No tumor has progressed. One patient had improvement in vision because of improvement in retinal detachment. Two patients experienced visual decline. One patient's visual decline was due to a vitreous hemorrhage, and the other's was due to hard exudates encroaching on the macula. One patient has developed a dry eye that is managed effectively with topical eye lubricants. CONCLUSIONS: This preliminary experience demonstrates that GKS is a feasible treatment option for small- to medium-sized choroidal melanomas. Longer follow up and additional patients will be required to improve the assessment and the ultimate tumor control and toxicity in this ongoing series.

Assessing the effect of radiocollars on juvenile guanaco survival.

To evaluate the potential impact of our research activities on guanacos (Lama guanicoe), we tested for effects of radiocollaring on juvenile (≤1 year of age) survival in Torres del Paine National Park, Chile during 1992-1996. The survival of collared (40.1%) and uncollared (38.2%) juveniles was not significantly different (G=0.08; P=0.77). Our results suggest that radiocollaring does not adversely affect the survival of juvenile guanacos. Although we observed no effect of radiocollaring, we still underline the importance of testing for effects of radiocollars in other wildlife investigations when feasible.

Segregation of presynaptic inputs on an identified target neuron in vitro: structural remodeling visualized over time.

Sensory cells of Aplysia form chemical synapses with the motor cell L7 in culture. Under certain conditions, sensory cells will also form electrical connections with each other. Sites of chemical synaptic interaction between the sensory cells and L7 are located at varicosities along sensory cell processes that overlie the main axons of L7, since these structures have been shown ultrastructurally to contain active zones. Previous studies have suggested that the distribution of sensory cell varicosities can be restricted to exclusive regions of the motor cell by the presence of other sensory cells. We wished to investigate (1) how this segregated pattern is generated over time and (2) whether electrical coupling between sensory cells has an effect on this segregated pattern. Using fluorescent dye injection and low-light video microscopy, we visualized the distribution of varicosities for each of two sensory cells growing on L7. In cases in which sensory cells are not electrically coupled, the varicosities from these two cells are spatially segregated on the target after 4 d in culture but not after 2 d in culture. Examination of the varicosity distribution of the same sensory cells on the second and third day of growth indicated both an increased rate in the elimination of varicosities from previously occupied areas and a restriction of varicosity formation in new areas of the target when a second sensory cell is present. For sensory cells that are electrically coupled, varicosities from these cells were not spatially segregated on the target even after 4 d in culture. These observations in vitro suggest that segregation of synaptic inputs by Aplysia sensory cells, which show little spontaneous activity of action potentials, can emerge over time via a process that includes both the elimination of existing sensory varicosities and the restriction of new varicosity formation. Our results also suggest that electrical connections between presynaptic cells can disrupt the segregation of their varicosities on a target, resulting in significant changes in the developing connectivity.

Effect of storage time and temperature on folacin and vitamin C levels in term and preterm human milk.

A survey of infant feeding practices indicated that 40% of the mothers who breast-fed their infants frequently expressed and stored their milk in the home refrigerator/freezer prior to feeding. Effects of different lengths of storage time on the levels of folacin and vitamin C in both term (T) and preterm (PT) human milk were examined. Folacin and vitamin C intakes of most mothers were such that the levels of these vitamins in milk appeared to have reached saturation. Folacin levels in T and PT milk were similar but were lower in both after three months of freezer storage compared to one week of storage. Vitamin C content in PT milk was significantly higher than that in T milk and did not change after three months of freezer storage, whereas the vitamin C level in T milk decreased significantly. After 24 hr refrigeration of T milk, vitamin C content was lower but the folacin level was similar to that observed prior to refrigeration. The findings indicated that T or PT human milk, stored for 3 months in the freezer, would provide the recommended allowance of vitamin C but not of folacin for infants.

Adverse reactions (aseptic meningitis) from 111-indium-DTPA cisternographic examinations.

Cisternographic examinations have become a relatively common procedure in the evaluation of patients with suspected communicating hydrocephalus. Adverse reactions to radiopharmaceuticals are relatively uncommon, particularly with the commonly used agents such as 111-In-DTPA and 169-Yb-DTPA. Adverse reactions after lumbar intrathecal instillation of 111-In-DTPA in three patients are described.