bluuebunny/crossref_metadata_2025 huggingface dataset:
The movements and breeding site fidelity of the natterjack toad (Bufo calamita) in an urban park near Paris (France) with management recommendations
Authors: Husté Aurélie , Clobert Jean , Miaud Claude
Published: November 2006

The isolation of animal populations due to urban activities provides a useful
framework for studying the consequences of landscape fragmentation. We
studied a population of natterjack toads (Bufo calamita) in an urban park
near Paris, France. In 2001 and 2002 we used radio-tracking to estimate the
terrestrial movements of adults around their breeding sites. Twenty-four
toads were equipped with internal transmitters in 2001 to record movements
during and after the breeding period. In 2002, 19 males were released at 300
and 380 meters from their breeding ponds. Natterjack toad movements around
and outside their breeding ponds were reduced compared to previous
observations on this species. The only exchanges that were observed occurred
between closely neighbouring breeding sites. During a translocation
experiment in 2002, 58% of the displaced males returned to their site of
capture and this happened mainly during the breeding period. The remaining
42% stayed close to the release site. There was no exchange of males between
distant breeding sites. Natterjack toad conservation needs to take into
account the high fidelity to a breeding site and the reduced breeding
dispersal and homing ability of these animals. Conservation biology in urban
landscapes constitutes a specific urban ecology with specific concepts such
as 'population area'. Information from this study can assist land managers
in establishing protected areas of high habitat quality around breeding
ponds in urban areas, and managing parks for the protection of amphibian
populations, particularly by facilitating exchanges between available
areas.
Breeding phenology of an amphibian community in a Mediterranean area
Authors: Richter-Boix Alex , Llorente Gustavo A. , Montori Albert
Published: November 2006

We studied the temporal breeding patterns and strategies of anuran
assemblages in the Mediterranean region over five consecutive years. We
collected monthly data on the number of clutches, tadpoles and juveniles
presence of six species in 98 ponds. The data showed a great temporal
segregation of species. Species using permanent ponds have a breeding peak
that is related to temperature whereas reproductive success in temporary
pond breeders is determined by rainfall pulses. Many species showed great
plasticity of reproduction with two peaks: one in spring and the other in
autumn. In spite of this temporal segregation, a large overlap was observed
among species during the larval phase period. Three species (Alytes
obstetricans, Pelodytes punctatus and Rana perezi) have over-wintering
tadpoles. We discuss temporal segregation, differences between species in
their breeding strategies and variable conditions between years as factors
that favour the temporal coexistence of species in the Mediterranean
region.
Myctolaimus platypi sp. n. (Nematoda: Cylindrocorporidae) isolated from the oak borer, Platypus quercivorus (Coleoptera: Platypodidae)
Authors: Kanzaki Natsumi , Kobayashi Masahide , Nozaki Ai , Futai Kazuyoshi
Published: November 2006

Myctolaimus platypi sp. n. is described and figured. The third-stage dauer
juveniles of M. platypi sp. n. were isolated from the underside of the
elytra of the oak borer, Platypus quercivorus, and were reared on an
Asparagine-Mannitol (A-M) agar. Specimens of adult nematodes for description
and measurements were collected from a 2-week-old culture on A-M agar. The
new species is characterised by having the stoma shorter than the
pro-metacorpus, shape of the rounded-cylindroid pro-metacorpus, the obvious
longitudinal striations on the cuticle, and thick cuticle. The male and
female of the new species have a body length of ca 700-1000 μm, a value of
ca 20, b value of ca 6, and c value of ca 10. Males of the new species have
strongly arcuate, C-shaped spicules 71 (62-80) μm long, 29 (25-35) μm long
gubernaculum with pointed distal end, and nine pairs of caudal papillae.
There is no bursa. Ceratosolenus is proposed as a junior synonym of
Myctolaimus and the following new combinations are also proposed: M.
anoplophorae comb. n.; M. inevectus comb. n.; and M. racemosa comb. n.
Linking soil properties and nematode community composition: effects of soil management on soil food webs
Authors: Sánchez-Moreno Sara , Minoshima Hideomi , Ferris Howard , Jackson Louise E.
Published: November 2006

The purported benefits of conservation tillage and continuous cropping in
agricultural systems include enhancement of soil ecosystem functions to
improve nutrient availability to crops and soil C storage. Studies relating
soil management to community structure allow the development of
bioindicators and the assessment of the consequences of management practices
on the soil food web. During one year (December 2003-December 2004), we
studied the influence of continuous cropping (CC), intermittent fallow (F),
standard tillage (ST) and no tillage (NT) on the nematode assemblage and the
soil food web in a legume-vegetable rotation system in California. The most
intensive systems included four crops during the study period. Tillage
practices and cropping pattern strongly influenced nematode faunal
composition, and the soil food web, at different soil depths. Management
effects on nematode taxa depended on their position along the
coloniser-persister (cp) scale and on their trophic roles. At the last
sampling date (December 2004), Mesorhabditis and Acrobeloides were
positively associated with NH+4, while Panagrolaimus and Plectus were
negatively correlated with certain phospholipid fatty acids (PLFA).
Microbial-feeders were in general associated with both bacterial and fungal
PLFA, microbial biomass C (MBC) by chloroform fumigation-extraction, total C
and N, NH+4 and NO−3, and were most abundant in the surface soil of the NTCC
treatment. Fungal-feeders were more closely related to PLFA markers of fungi
than to ergosterol, a purported fungal sterol. Discolaimus, Prionchulus,
Mylonchulus and Aporcelaimidae, in contrast, were associated with
intermittent fallow and deeper soil layers. The organisms in the higher
levels of the soil food web did not respond to the continuous input of C in
the soil and a long recovery period may be required for appropriate taxa to
be reintroduced and to increase. At the end of the experiment, each
treatment supported quite different nematode assemblages and soil food
webs.
Steinernema ashiuense sp. n. (Nematoda: Steinernematidae), a new entomopathogenic nematode from Japan
Authors: Phan Long K. , Takemoto Shuhei , Futai Kazuyoshi
Published: November 2006

Steinernema ashiuense sp. n. was collected by a Galleria baiting method from
grassland along the riverbank of the Yura river, near the Ashiu Research
Forest Station of Kyoto University. The new species is characterised by an
infective juvenile body length of 768 (720-800) μm, lateral field with five
equally developed ridges (i.e., six lines or incisures), head smooth lacking
horn-like structures, excretory pore located at level of middle of pharynx,
hyaline portion short (ca one-third of tail length). Males have 50-65 μm
long, broad, slightly yellowish spicules; spicule length / spicule width = 4
(3.5-4.4), and two subventral and one subdorsal pair of genital papillae in
the postcloacal region. The analysis of ITS-rDNA sequence placed S.
ashiuense sp. n. in the 'feltiae-kraussei-oregonense' group in the clade
containing S. robustispiculum and S. monticolum. It can be distinguished
from these species by morphological characters of the infective juveniles
and males.
Aquatic macrophytes as a habitat for free-living nematodes
Authors: Vidaković Jasna , Bogut Irella
Published: November 2006

The composition, trophic structure and diversity of nematode assemblages
associated with three aquatic macrophyte species (Polygonum amphibium, Carex
sp., Ceratophyllum demersum) were surveyed. Sampled stands were present at
the three sites of the north bank in the Čonakut Channel (Nature Park
Kopački rit, Croatia). They were all submerged during the period of
investigation, which included two vegetation seasons. Nematode abundances
(expressed as a number of individuals per 100 g of macrophyte dry weight)
differ between the two vegetation seasons and between the sites, but not
between the macrophyte species. In total, 19 nematode species were recorded.
Chromadorina viridis, C. bioculata, Brevitobrilus stefanskii, Eutobrilus
notus, Prodorylaimus longicaudatus and Ethmolaimus sp. were associated with
all macrophyte species. Genera Eutobrilus, Brevitobrilus and Chromadorina
were present at the highest relative abundances. Species diversity (H and
Simpson's D) and evenness (Pielou's J), calculated on the nematode species
level, display little or no change in relation to different macrophyte
species. Ceratophyllum demersum associated nematode fauna had distinct
dominance of one species (Eutobrilus notus) and consequently lower evenness,
which was not statistically significant. Chewers (CH) represented the
dominant trophic group of total nematode abundance for all three macrophyte
species followed by epistrate feeders (EF). Detritus feeders (DF) and
suction feeders (SF) were represented by low relative abundances. This paper
is a contribution to ecology of aquatic nematodes associated with macrophyte
species in mesoeutrophic to eutrophic slow flowing channel.
Article 76 of the UN Convention on the Law of the Sea—Implementation Problems from the Technical Perspective
Authors: Carleton Chris
Published: November 2006

The paper will discuss the technical problems experienced by coastal States when considering and preparing claims to an extended continental shelf in accordance with Article 76 and Annex II to the UN Convention on the Law of the Sea.The initial requirement to ascertain whether the State has the possibility of claiming a extended continental shelf and if so the securing of the political will to make provision for the technical process required to bring it to fruition will be discussed followed by the technical pitfalls that await an unwary State in the desk top study procedure.The paper will then discuss the data gathering phase and the subsequent processing and assessment of the data and the possible technical difficulties that may be encountered.Finally the paper will outline the vexed question of claims on ridges, focusing on what a ridge actually is within the wording of Article 76. The differences, if any between an "oceanic" ridge and a "submarine" ridge and possible claim solutions that may be considered by the claiming State. The lack of guidance from the Commission on the Limits of the Continental Shelf (CLCS) concerning this issue will also be highlighted.
Sustaining Tobacco Control Coalitions Amid Declining Resources
Authors: Carver Vivien , Reinert Bonita , Range Lillian M.
Published: November 2006

Mississippi is unique among the 50 states in settling a lawsuit against tobacco companies earlier than the Master Settlement Agreement, devoting a relatively high amount of per capita funding on tobacco control, and avoiding tobacco-control budget cuts. Using a social-ecological approach combining insider and outsider strategies, tobacco-prevention coalitions in Mississippi succeeded in sustaining funding despite serious obstacles. Lessons learned included taking specific actions to embed themselves in the local community, wisely aligning with legislators, choosing courageous and effective champions, and ensuring that people are keenly aware of their existence and efforts. In using these strategies, tobacco-prevention coalitions in Mississippi have become an institution of the community and in so doing helped sustain their funding.
Peroxiredoxin 2 functions as a noncatalytic scavenger of low-level hydrogen peroxide in the erythrocyte
Authors: Low Felicia M. , Hampton Mark B. , Peskin Alexander V. , Winterbourn Christine C.
Published: November 2006

Peroxiredoxin 2 (Prx2), a thiol-dependent peroxidase, is the third most abundant protein in the erythrocyte, and its absence in knock-out mice gives rise to hemolytic anemia. We have found that in human erythrocytes, Prx2 was extremely sensitive to oxidation by H2O2, as dimerization was observed after exposure of 5 × 106 cells/mL to 0.5 μM H2O2. In contrast to Prx2 in Jurkat T lymphocytes, Prx2 was resistant to overoxidation (oxidation of the cysteine thiol to a sulfinic/sulfonic acid) in erythrocytes. Reduction of dimerized Prx2 in the erythrocyte occurred very slowly, with reversal occurring gradually over a 20-minute period. Very low thioredoxin reductase activity was detected in hemolysates. We postulate that this limits the rate of Prx2 regeneration, and this inefficiency in recycling prevents the overoxidation of Prx2. We also found that Prx2 was oxidized by endogenously generated H2O2, which was mainly derived from hemoglobin autoxidation. Our results demonstrate that in the erythrocyte Prx2 is extremely efficient at scavenging H2O2 noncatalytically. Although it does not act as a classical antioxidant enzyme, its high concentration and substrate sensitivity enable it to handle low H2O2 concentrations efficiently. These unique redox properties may account for its nonredundant role in erythrocyte defense against oxidative stress.
Convergent Roles of α‐Synuclein, DA Metabolism, and the Ubiquitin‐Proteasome System in Nigrostriatal Toxicity
Authors: FORNAI FRANCESCO , LAZZERI GLORIA , DI POGGIO ADOLFO BANDETTINI , SOLDANI PAOLA , DE BLASI ANTONIO , NICOLETTI FERDINANDO , RUGGIERI STEFANO , PAPARELLI ANTONIO
Published: November 2006

Abstract:  Recent studies disclosed the relevance of specific molecules for the onset of Parkinson's disease (PD) and for the composition of neuronal inclusions. The scenario which is now emerging leads to identify a potential common pathway named the ubiquitin‐proteasome (UP) system. In line with this, striatal or systemic inhibiton of the UP system causes experimental Parkinsonism characterized by the formation of neuronal inclusions. 1‐Methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP), which is also a complex I inhibitor, has been used for decades to produce experimental Parkinsonism with no evidence for neuronal inclusions in rodents. This leaves open the question whether neuronal inclusions need an alternative mechanism or the inhibition of complex I needs to be carried out continuously to build up inclusions. In the present article, we administered continuously MPTP. In these experimental conditions we compared the neurological consequence of intermittent versus continuous MPTP. In both cases we observed a severe dopamine (DA) denervation and cell loss. However, when MPTP was delivered continuously, spared DA nigral neurons develop ubiquitin, parkin, and α‐synuclein positive inclusions, which are not detectable after intermittent dosing. The onset of Parkinsonism is associated with inhibition of the UP system. We compared these results with those obtained with amphetamine derivative in vivo and in vitro in which occurrence of neuronal inclusions was associated with inhibition of the UP system and we evaluated the role of DA metabolism in inducing these effects.
Repeated Methamphetamine Administration Alters Expression of the NMDA Receptor Channel ɛ2 Subunit and Kinesins in the Mouse Brain
Authors: YAMAMOTO HIDEKO , IMAI KAZUHIDE , KAMEGAYA ETSUKO , TAKAMATSU YUKIO , IRAGO MASASHI , HAGINO YOKO , KASAI SINYA , SHIMADA KIYO , YAMAMOTO TOSHIFUMI , SORA ICHIRO , KOGA HISASHI , IKEDA KAZUTAKA
Published: November 2006

Abstract:  Repeated amphetamine administration results in behavioral sensitization. Behavioral sensitization related to abuse and/or relapse may be associated with stable changes in gene expression. To explore the participating genes, we examined the changes in gene expression levels 24 h or 21 days (long‐term withdrawal period) after chronic methamphetamine (METH) treatment for 2 weeks. The expression of several genes related to glutamatergic neural transmission was altered, although changes in the corresponding protein expression were not always consistent with the results for mRNA expression. Of interest, in the frontal cortex of mice treated with METH for 2 weeks, protein expression levels of KIF17 and the N‐methyl‐D‐asparate (NMDA) receptor channel ɛ2 subunit (NRɛ2) were concomitantly increased. The alteration in expression of these proteins, KIF17 and NRɛ2, might be a part of the molecular basis of the behavioral sensitization to METH.
Age‐Dependent Effects of Methamphetamine on VMAT‐2
Authors: RAU KRISTI S. , TRUONG JANNINE G. , WILKINS DIANA G. , FLECKENSTEIN ANNETTE E. , HANSON GLEN R.
Published: November 2006

Abstract:  Abuse of methamphetamine (METH) among adolescents and young adults is concerning since studies have demonstrated that multiple administrations of high‐dose METH induce persistent dopaminergic deficits. METH has also been shown to reduce dopamine (DA) uptake by the vesicular monoamine transporter‐2 (VMAT‐2) and to reduce the amount of VMAT‐2 protein in a purified vesicular fraction. VMAT‐2 plays a critical role in the sequestration of DA in dopaminergic nerve terminals. This function is important since DA can oxidize rapidly to form highly reactive species. It is likely that disruption of this normal intracellular processing of DA contributes to oxidative sequences ultimately leading to persistent deficits. Interestingly, METH appears to be less toxic in adolescent rats compared to young adult rats. VMAT‐2 is proposed to play an important role in the age‐dependent difference. Since the effect of METH on the function and quantity of VMAT‐2 has primarily been studied in young adult rats and since developmental changes in the dopaminergic system are reported to occur between adolescence and adulthood, it is important to determine if there is an age‐dependent difference in response of VMAT‐2 to METH.
In PC12 Cells Neurotoxicity Induced by Methamphetamine Is Related to Proteasome Inhibition
Authors: LAZZERI GLORIA , LENZI PAOLA , GESI MARCO , FERRUCCI MICHELA , FULCERI FEDERICA , RUGGIERI STEFANO , BRUNO VALERIA , FORNAI FRANCESCO
Published: November 2006

Abstract:  Neurodegenerative disorders are featured by a variety of pathological hallmarks, and very often they are characterized by neuronal inclusions in specific brain nuclei. Occurrence of neuronal inclusions has been often related to the onset of cell death. Recent studies demonstrated that amphetamine derivatives produce intracellular inclusions, which are reminiscent of those occurring in degenerative disorders. In the present article, we analyzed the correlation between neuronal inclusions and cell death using methamphetamine (METH) in PC12 cell cultures. We found that the dose necessary to induce cell death is higher compared with that required to induce inclusions formation. Our results demonstrate a dissociation between formation of inclusion bodies and cell death suggesting that neuronal inclusions do not necessarily lead to cell death. The conclusions of the present article suggest that the onset of inclusion bodies represents a slight consequence of toxicity, which requires a prolonged cell viability to take place.
Alterations in Blood–Brain Barrier Function by Morphine and Methamphetamine
Authors: SHARMA HARI SHANKER , ALI SYED F.
Published: November 2006

Abstract:  The possibility that stress associated with morphine and amphetamine administration or withdrawal will influence the blood–brain barrier (BBB) and brain dysfunction was examined in a rodent model. Repeated daily administration of morphine (10 mg/kg, i.p.) resulted in drug dependence in rats on the sixth day and onwards. Measurement of the BBB permeability to large molecule tracers normally bound to proteins, e.g., Evans blue albumin and radioiodine ([131]Iodine) did not show any leakage on the 12th day of drug dependence. On the other hand, spontaneous withdrawal of morphine on day 1 resulted in profound stress symptoms. These symptoms were much more intense on the second day of morphine withdrawal. Alterations in the BBB to protein tracers were seen in several regions of the brain. This increase in BBB to protein tracers was most pronounced on the second day of morphine withdrawal. These rats also exhibited abnormal neuronal, glial and stress protein, the heat‐shock protein 72 kD (HSP‐72 kD) response. On the other hand, acute administration of methamphetamine (40 mg/kg, i.p.) in mice resulted in marked extravasation of endogenous serum protein as seen with increased expression of albumin immunohistochemistry. These observations suggest that psychostimulants and associated stress are capable to influence the brain function, probably through modifying the BBB function, not reported earlier.
Calpain Activation in Apoptosis of Motoneurons in Cell Culture Models of Experimental Parkinsonism
Authors: SAMANTARAY SUPRITI , RAY SWAPAN K. , ALI SYED F. , BANIK NAREN L.
Published: November 2006

Abstract:  Parkinson's disease (PD) is a movement disorder characterized by progressive degeneration of primarily the dopaminergic neurons in the substantia nigra (SN). The present study briefly describes our findings to support the hypothesis that there is a possibility of degeneration of spinal cord (SC) motoneurons in course of parkinsonism. In cell culture models of experimental parkinsonism, we examined the degeneration of ventral SC motoneuron cell line (VSC4.1) following exposure to two different toxins, such as 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) and rotenone. Our studies suggested calpain activation in the apoptosis of VSC4.1 motoneurons due to exposure to these parkinsonian toxins. Furthermore, our study showed the toxic effects of the dopaminergic toxin methamphetamine (METH) on VSC4.1 cells. The results strongly implicated a possible role for calpain in the mechanism of motoneuron apoptosis during parkinsonian degeneration, at large. Hence, we examined the neuroprotective efficacy of calpeptin, a specific inhibitor of calpain, in cell culture model of experimental parkinsonism.
Neural Effects of MDMA as Determined by Functional Magnetic Resonance Imaging and Magnetic Resonance Spectroscopy in Awake Marmoset Monkeys
Authors: MEYER JERROLD S. , BREVARD MATTHEW E. , PIPER BRIAN J. , ALI SYED F. , FERRIS CRAIG F.
Published: November 2006

Abstract:  We used functional magnetic resonance imaging (fMRI) to investigate the acute effects of a recreational dose (1 mg/kg p.o.) of 3,4‐methylenedioxymethamphetamine (MDMA) on regional brain activity in awake, restrained marmoset monkeys. In a second study, magnetic resonance spectroscopy (MRS) and postmortem measurements of serotonin transporter (SERT) binding and serotonin (5‐HT) concentrations were used to determine the neurotoxic effects of low (4 × 1 mg/kg p.o.) and high (4 × 10 mg/kg i.m.) doses of MDMA. Several brain areas were significantly activated by the low oral dose of MDMA, including the midbrain raphe nuclei, hippocampus, hypothalamus, amygdala, and the corticostriatal circuit composed of the dorsal thalamus, sensory motor cortex, and basal ganglia. MDMA activated the primary visual cortex under baseline conditions and also enhanced the visual cortical response to photic stimulation. The onset of brain activation correlated well with the rise in plasma MDMA concentrations measured in separate monkeys given the same drug treatment. In the second study, the ratio of N‐acetylaspartate (NAA; a putative neuronal marker) to creatine was significantly reduced in the hypothalamus following either MDMA treatment regimen, suggesting a particular vulnerability of this structure to MDMA‐induced damage. Monkeys given the high‐dose regimen also showed prolonged hyperthermia and reductions in 5‐HT and SERT in a number of brain areas. These results are the first to identify the pattern of MDMA‐induced brain activation in a nonhuman primate model, and they further suggest that even recreational doses of MDMA may have adverse consequences as indicated by the reduced hypothalamic NAA/creatine ratio.
MDMA Induces Caspase‐3 Activation in the Limbic System but not in Striatum
Authors: TAMBURINI ILARIA , BLANDINI FABIO , GESI MARCO , FRENZILLI GIADA , NIGRO MARCO , GIUSIANI MARIO , PAPARELLI ANTONIO , FORNAI FRANCESCO
Published: November 2006

Abstract:  Several studies, carried out in chronic (+/−) 3,4‐methylenedioxymethamphetamine (MDMA) abusers, have shown memory loss and cognitive impairment, as well as persistent electroencephalographic changes. This suggests that, at least in humans, forebrain areas, including the limbic system, might be altered by MDMA. Consistently, recent experimental evidences suggest that, in rodents, MDMA, besides effects on the basal ganglia, produces alterations in the hippocampus. Therefore, the aim of the present article was to investigate whether treatment with MDMA produces activation of the caspase‐3 enzyme, which is part of an enzymatic pathway involved in cell death, within limbic areas (i.e., hippocampus, amygdala, and piriform cortex) and striatum. A marked induction of caspase‐3 activity was demonstrated in the amygdala and hippocampus, although MDMA did not affect caspase‐3 activity neither in the striatum nor in the frontal cortex. These data indicate that limbic structures possess a high sensitivity to MDMA with respect to the activation of at least one step in the apoptotic pathway. Potential implications and pitfalls of such an experimental observation are reported.
Brain Blood Flow SPET Imaging in Heroin Abusers
Authors: BOTELHO MARIA FILOMENA , RELVAS JOÃO S. , ABRANTES MARGARIDA , CUNHA MARIA JOÃO , MARQUES TIAGO R. , ROVIRA EUGÉNIA , FONTES RIBEIRO CARLOS A. , MACEDO TICE
Published: November 2006

Abstract:  To assess whether chronic heroin abuse may generate vascular central nervous deficits, we studied the profile of vascular alterations in 17 heroin addicts (14 males mean age 31 years, range 23–39 years and 3 females mean age 33 years, range 30–35 years) before and, in one of them, 10 weeks after an ultra‐rapid heroin detoxification. Using the functional technique of single‐photon emission tomography (SPET) with 740 MBq of 99mTc‐hexametazine (HMPAO) and computational brain‐mapping techniques by means of a Talairach analysis, we determined the pattern of vascular brain alterations associated with chronic heroin abuse. Compared with controls, subjects who had used heroin chronically showed a decrease of global brain perfusion that was more significant in the frontal cortex—mainly in orbito‐frontal regions, as well as in the occipital and temporal lobes. All patients showed marked asymmetric perfusion of the basal ganglia and the majority of them showed also an asymmetric perfusion of cerebellum. In addition, there were small activated areas dispersed in the occipital lobe (3 of 17) and apex region (4 of 17). In conclusion, decreased perfusion in heroin addicts was found in regions involved in the control of attention, motor speed, memory and visual–spatial processing. The prefrontal cortex is involved in decision making and inhibitory control, processes disturbed in heroin addicts who have stopped heroin consumption. A reduction in regional perfusion may reflect ongoing subtle neurocognitive deficits, which are consistent with the maintenance of asymmetry of the basal nuclei.
CNS Aspects of Prenatal Drug Exposure
Authors: VELÍŠEK LIBOR
Published: November 2006

Abstract:  Studies of the effects of prenatal exposure (to drugs or environmental factors) on postnatal brain morphology and function have an important role in assessing adverse effects of prenatal administration of corticosteroids in obstetrics, in studying the impairment of the offspring due to maternal drug abuse, as well as in studies of the influence of other environmental factors (such as toxins or stress). Timing, duration, and dose of the prenatal exposure play a significant role in the postnatal expression of the impact. However, data interpretation may be complicated by additional factors. As mixed litters of prenatally exposed subjects are evaluated, significant differences between males and females may occur. Additionally in females, cyclical changes in ovarian steroids may interfere with the effects of prenatal impact. Developmental differences may be also present, and data from infant, juvenile, prepubertal, and adult individuals cannot be simply compared. Finally, prenatal treatment is a stressful event and may present itself as prenatal stress, misguiding the interpretation. Postnatal environmental factors in raising the offspring, such as housing, maternal care, light–dark cycle, and weaning age can also change the data in such a way, which makes comparisons between different research laboratories impossible.
Nitric Oxide and Oxidative Stress in the Brain of Rats Exposed In Utero to Cocaine
Authors: BASHKATOVA VALENTINA , MEUNIER JOHANN , VANIN ANATOLY , MAURICE TANGUI
Published: November 2006

Abstract:  The role of nitric oxide (NO) and lipid peroxidation (LPO) processes in the physiological deficits induced by in utero cocaine exposure was examined in rats. NO generation in the hippocampus and cortex was detected using the electron paramagnetic resonance and LPO products were measured as thiobarbituric acid reactive species (TBARS). Pregnant Sprague‐Dawley rats received a daily intraperitoneal injection of 20 mg/kg cocaine (IUC) or saline solution for control dams (IUV) between E17–E20. NO level was lower in the brain of IUC rats at postnatal day 1 and 2, but not 4, as compared with IUV rats. TBARS content was increased at day 1–4. Animals were used for behavioral testing at 25 days of age. Both NO and TBARS were elevated in the hippocampus of IUC rats as compared with IUV rats. Juvenile IUC rats developed significant learning impairments in the water‐maze, as revealed by probe test retrieval deficits. Behavioral sessions resulted in a significant increase of TBARS levels only in IUV animals. Therefore, IUC rats showed a significant oxidative stress in basal conditions that may be related to their impaired learning ability. We did not find direct correlation between the changes in NO generation and intensity of LPO processes. It may probably mean that changes in intensity of LPO processes observed during prenatal cocaine exposure are not directly linked to NO pathway activation.
Effect of Massive Weight Loss on Inflammatory Adipocytokines and the Innate Immune System in Morbidly Obese Women
Authors: Manco Melania , Fernandez-Real J. Manuel , Equitani Francesco , Vendrell Joan , Valera Mora Maria Elena , Nanni Giuseppe , Tondolo Vincenzo , Calvani Menotti , Ricart Wilfredo , Castagneto Marco , Mingrone Geltrude
Published: November 2006

Context: Obesity may be regarded as a low-grade inflammatory state.

Objective: The aim of this study was to evaluate changes in pro-inflammatory adipocytokines and the innate immune system, cardiovascular risk, and insulin sensitivity after massive weight loss.

Design: This was a longitudinal study.

Setting: The study was conducted at Catholic University, Rome.

Subjects and Methods: There were 10 normoglucose-tolerant obese women evaluated before and 36 months after bilio-pancreatic diversion (BPD). Glucose sensitivity (M value) was estimated using the euglycemic-hyperinsulinemic clamp. Mannan-binding lectin (MBL), bactericidal/permeability increasing protein (BPI), α-defensins, soluble CD14 receptor (sCD14), C-reactive protein, adiponectin, leptin, visfatin, IL-6, and TNF-α were assayed.

Results: After massive weight loss (53% of excess body weight), leptin (P ≤ 0.0001), IL-6 (P ≤ 0.0001), α-defensins (P ≤ 0.001), and C-reactive protein (P ≤ 0.0001) decreased significantly. Adiponectin increased significantly (P ≤ 0.001). Of the nine subjects who lost more than 20% of body mass index, sCD14 (2.87 ± 0.5 to 2.55 ± 0.5; P = 0.016) and visfatin levels (12.20 ± 0.93 to 10.63 ± 1.93 ng/ml; P = 0.045) decreased significantly. No significant changes were observed in TNF-α, BPI, or MBL. Insulin sensitivity more than doubled after BPD (P ≤ 0.0001). sCD14 changes were significantly associated with body mass index (r0 = 0.80; P = 0.003) and M changes (r0 = −0.59; P = 0.03). MBL correlated with insulin sensitivity in obese (r0 = 0.93; P = 0.0001) and post-BPD women (r0 = 0.66; P = 0.038). Adiponectin correlated negatively with cardiovascular risk (r0 = −0.709; P = 0.02) and IL-6 (r0 = −0.634; P = 0.05). Multiple linear regression analysis showed that changes in sCD14 were also significantly related to changes in insulin sensitivity.

Conclusions: Surgically induced weight loss is capable of reversing low-grade inflammation, at least partially. The relationships between sCD14, MBL, BPI, and glucose sensitivity, and the role of TNF-α in obesity warrant further investigation.
New insights into the molecular basis of desmoplakinand desmin-related cardiomyopathies
Authors: Lapouge Karine , Fontao Lionel , Champliaud Marie-France , Jaunin Fabienne , Frias Miguel A. , Favre Bertrand , Paulin Denise , Green Kathleen J. , Borradori Luca
Published: November 2006

Desmosomes are intercellular adhesive complexes that anchor the intermediate filament cytoskeleton to the cell membrane in epithelia and cardiac muscle cells. The desmosomal component desmoplakin plays a key role in tethering various intermediate filament networks through its C-terminal plakin repeat domain. To gain better insight into the cytoskeletal organization of cardiomyocytes, we investigated the association of desmoplakin with desmin by cell transfection, yeast two-hybrid, and/or in vitro binding assays. The results indicate that the association of desmoplakin with desmin depends on sequences within the linker region and C-terminal extremity of desmoplakin, where the B and C subdomains contribute to efficient binding; a potentially phosphorylatable serine residue in the C-terminal extremity of desmoplakin affects its association with desmin; the interaction of desmoplakin with non-filamentous desmin requires sequences contained within the desmin C-terminal rod portion and tail domain in yeast, whereas in in vitro binding studies the desmin tail is dispensable for association; and mutations in either the C-terminus of desmoplakin or the desmin tail linked to inherited cardiomyopathy seem to impair desmoplakindesmin interaction. These studies increase our understanding of desmoplakin-intermediate filament interactions, which are important for maintenance of cytoarchitecture in cardiomyocytes, and give new insights into the molecular basis of desmoplakin- and desmin-related human diseases.
The DNA helicase ChlR1 is required for sister chromatid cohesion in mammalian cells
Authors: Parish Joanna L. , Rosa Jack , Wang Xiaoyu , Lahti Jill M. , Doxsey Stephen J. , Androphy Elliot J.
Published: November 2006

It has recently been suggested that the Saccharomyces cerevisiae protein Chl1p plays a role in cohesion establishment. Here, we show that the human ATP-dependent DNA helicase ChlR1 is required for sister chromatid cohesion in mammalian cells. Localization studies show that ChlR1 diffusely coats mitotic chromatin in prophase and then translocates from the chromatids to concentrate at the spindle poles during the transition to metaphase. Depletion of ChlR1 protein by RNA interference results in mitotic failure with replicated chromosomes failing to segregate after a pro-metaphase arrest. We show that depletion also results in abnormal sister chromatid cohesion, determined by increased separation of chromatid pairs at the centromere. Furthermore, biochemical studies show that ChlR1 is in complex with cohesin factors Scc1, Smc1 and Smc3. We conclude that human ChlR1 is required for sister chromatid cohesion and, hence, normal mitotic progression. These functions are important to maintain genetic fidelity.
Involvement of the Src-cortactin pathway in podosome formation and turnover during polarization of cultured osteoclasts
Authors: Luxenburg Chen , Parsons J. Thomas , Addadi Lia , Geiger Benjamin
Published: November 2006

Osteoclasts are large, multinucleated cells that adhere to bone via podosomes, and degrade it. During osteoclast polarization, podosomes undergo reorganization from a scattered distribution, through the formation of clusters and ring super-structures, to the assembly of a sealing zone at the cell periphery. In the present study, we demonstrate that the levels of podosome-associated actin, and its reorganization in cultured osteoclasts, radically increase upon formation of podosome rings. At the peripheral ring, actin levels and dynamic reorganization were high, whereas paxillin, associated with the same adhesion super-structure, remained relatively stable. These dynamic changes were regulated by the tyrosine kinase pp60c-Src, whose scaffolding activity supported the assembly of immature stationary podosomes; its catalytic activity was essential for podosome maturation and turnover. The enhanced dynamic reorganization of podosomes during osteoclast polarization was inversely related to the local levels of tyrosine phosphorylation of the Src substrate, cortactin. Furthermore, overexpression of cortactin, mutated at its major Src phosphorylation sites, enhanced actin turnover, suggesting that podosome dynamics in polarizing osteoclasts are attributable to the downregulation of cortactin activity by its Src-dependent phosphorylation.
Dynamic regulation of ERK2 nuclear translocation and mobility in living cells
Authors: Costa Mario , Marchi Matilde , Cardarelli Francesco , Roy Anusrhee , Beltram Fabio , Maffei Lamberto , Ratto Gian Michele
Published: November 2006

The extracellular signal-regulated protein kinase ERK1/2 is a crucial effector linking extracellular stimuli to cellular responses: upon phosphorylation ERK [also known as mitogen-activated protein kinase P42/P44 (MAPK)] concentrates in the nucleus where it activates specific programs of gene expression. Notwithstanding the importance of this process, little is known about the modalities, time course and regulation of ERK exchange between nucleus and cytoplasm in living cells. We visualized the dynamic of nuclear translocation by expressing low levels (<150 nM) of fluorescently tagged ERK2 in living fibroblasts. Time-lapse imaging demonstrated that nuclear concentration can change bidirectionally with a time constant of a few minutes. The increase of nuclear concentration requires continuous MEK (also known as MAPK kinase) activity upstream of ERK and is rapidly reduced by the operation of phosphatases. We measured quantitatively the speed of ERK2 shuttling between nucleus and cytoplasm and determined that shuttling accelerated after ERK activation, becoming fast enough not to be rate-limiting for translocation. Finally, we demonstrated that ERK2 did not diffuse freely in the nucleus and that diffusion was further impeded after phosphorylation, suggesting the formation of complexes of low mobility. These results show that nucleocytoplasmic trafficking of ERK2 and its mobility are dynamically regulated in living cells.
The 46-kDa mannose 6-phosphate receptor does not depend on endosomal acidification for delivery of hydrolases to lysosomes
Authors: Probst Olivia C. , Ton Phuong , Svoboda Barbara , Gannon Andrew , Schuhmann Werner , Wieser Johannes , Pohlmann Regina , Mach Lukas
Published: November 2006

In mammalian cells, the mannose 6-phosphate receptor pathway accounts for the transport of most soluble acid hydrolases to lysosomes. It is believed that dissociation of mannose 6-phosphate receptors and their ligands is entirely driven by the acidic environment in endosomal compartments. Indeed, pH-perturbing substances such as ammonium chloride and monensin have been shown to inhibit lysosomal enzyme targeting in cells that express both known mannose 6-phosphate receptors. We now demonstrate that ammonium chloride and monensin exert modest effects on the intracellular retention of lysosomal hydrolases in murine cells that synthesize only the 46-kDa mannose 6-phosphate receptor. Neither ammonium chloride nor monensin induces changes to the subcellular localization of lysosomal hydrolases and the 46-kDa mannose 6-phosphate receptor in these cells. This suggests that endosomal dissociation of the receptor and its ligands still occurs in the presence of these agents. We conclude that the murine 46-kDa mannose 6-phosphate receptor has the capacity to deliver its cargo proteins to lysosomes even in the absence of endosomal acidification.
Adsorption Reaction Constants between Nanosilica/Nanodiamond and Lysozyme Molecule at pH = 11.0
Authors: Wu Victor Wei-Keh
Published: November 2006

Adsorption reaction constants of chicken egg lysozyme of 0–1000 nM prepared with potassium phosphate buffer solution (PPBS) of 7.0 mM and at pH = 11.0 on the surfaces of nanosilica and nanodiamond of diameter 100 nm by fluorescence method have been determined as 4.0 × 107 and 1.5 × 108 nM−1, respectively. The Langmuir isotherm can be well followed under the assumption of monolayer adsorption on both surfaces. The available surface areas per individual lysozyme molecule adsorbed on nanosilica and nanodiamond within the linear regions of Langmuir isotherms can be approximated with 2 and 10 nm2, respectively.
Self-assembled Multilayer Formed by Alternate Stacking of Zirconium and Terephthalic Acid Layers
Authors: Yonezawa Hiroyuki , Lee Kyung-Hwang , Murase Kuniaki , Sugimura Hiroyuki
Published: November 2006

A self-assembled multilayer consisting of transition metal and biscarboxyl acid was fabricated by simply immersing an oxide-covered silicon substrate into zirconium (Zr) n-butoxide and terephthalic acid (TPA) solutions alternately. In this multilayer, two TPA monolayers were bridged with a ZrIV monolayer. The chemistry connecting these monolayers is most likely coordinate bonds between ZrIV ions and carboxyl groups.
Thermally Reversible Structural Transformation Involving a C–H···O Hydrogen Bond in a Supramolecular Crystal
Authors: Ishii Daisuke , Yamada Takeshi , Iyoda Tomokazu , Yoshida Hirohisa , Nakagawa Masaru
Published: November 2006

A molecular crystal of 6-[2-propyl-4-(4-pyridylazo)phenoxy]hexanoic acid prepared by sublimation showed two thermally reversible transitions at 17 and 172 °C on heating. Temperature dependence of its X-ray diffraction profile analyzed on the basis of its crystal structure revealed that the reversible transitions were related to a thermally induced hierarchical structural transformation involving cleavage of a C–H···O hydrogen bond, followed by cleavage of a O–H···N hydrogen bond.
Homogeneous Ag Particle Formation Confirmed by Real-time In Situ Surface-enhanced Raman Scattering Measurements under Microwave Irradiation
Authors: Tsukahara Yasunori , Nakamura Takashi , Kobayashi Taishi , Wada Yuji
Published: November 2006

In situ surface-enhanced Raman scattering (SERS) was applied to observe the early stage of the formation of Ag nanoparticles in solution under microwave (MW) irradiation. Rise of SERS successfully observed for Rhodamine 6G confirmed homogeneous particle formation due to homogeneous and rapid heating under MW irradiation.
Diastereo- and Enantioselective Synthesis of 3-Amino-3,4-dihydropyran-2-ones by Tandem Michael Addition and Lactonization Using a Chiral Quaternary Ammonium Phenoxide
Authors: Nagao Hitoshi , Yamane Yoshinobu , Mukaiyama Teruaki
Published: November 2006

The first efficient synthesis of 3-amino-3,4-dihydropyran-2-ones from glycine-derived silyl enolates and α,β-unsaturated ketones was successfully performed by using quaternary ammonium phenoxide prepared from cinchonidine. In this asymmetric reaction, the corresponding 3-amino-3,4-dihydropyran-2-ones were obtained in high yields with complete diastereoselectivities and good to excellent enantioselectivities.
Density Functional Study of Catalytic Oxygen Reduction Reaction (ORR) on Cathode Electrode for Fuel Cell System
Authors: Suga Yoshinori
Published: November 2006

Density functional studies have performed for the platinum cluster model of cathode catalysts that are used in polymer electrolyte membrane fuel cell (PEMFC). A generalized gradient approximation treatment of total energies denoted that the activation barrier for oxygen dissociation after the proton-transfer step, as intermediate species formation, would have similar magnitude that determined by the temperature dependent oxygen reduction Tafel plot measurements.
Hydrothermal Synthesis of Ultrafine β-FeOOH Nanorods as Cathode Materials for Lithium Ion Batteries
Authors: Zhou Fu , Zhao Xuemei , Yuan Cunguang , Xu Hai
Published: November 2006

β-FeOOH nanorods with the diameter of only 10 nm were fabricated through a facile PEG-assisted hydrothermal synthetic route, which was the smallest dimension reported for the fabrication of β-FeOOH one-dimensional (1-D) nanostructures so far. The as-prepared ultrafine β-FeOOH nanorods were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and galvanostatic tests. Electrochemical tests on the as-obtained ultrafine β-FeOOH nanorods revealed that they exhibited excellent electrochemical properties with a large discharge capacity of 290 mA h g−1 and good cycleability, which enabled them to be applied as superior cathode materials for lithium ion battery systems.
Synthesis and Two-photon Properties of New Perylene Bisimide Derivatives
Authors: Gao Bo , Lu Changgui , Xu Jin , Meng Fanshun , Cui Yiping , Tian He
Published: November 2006

The synthesis of some novel perylene bisimide derivatives was reported and their linear absorption, emission, and two-photon properties were measured and discussed. Two-photon cross-sections for these compounds were determined to be 8735 GM maximum (nonlinear transmittance, ≈7 ns, 10 Hz and 850 nm). The frequency upconversion fluorescence was observed under the excitation of 850-nm-nanoseconds laser pulses with the peaks located around 669 nm.
Otitis media (silent): A potential cause of childhood meningitis
Authors: Djerić Dragoslava R. , Schachern Patricia A. , Paparella Michael M. , Jaramillo Mario , Haruna Shinichi , Bassioni Mohktar
Published: November 2006

Sixteen temporal bones from 8 infants with otitis media, who died of meningitis, and 6 controls from infants with only otitis media, were studied histologically. All bones contained middle ear effusion and residual mesenchyme, but, unlike the controls, the meningitic cases showed considerable histopathological tissue changes of chronic and acute otitis media and chronic inflammatory cells in the round window membrane and within the perilymph, the modiolus, and the cochlear aqueduct, suggesting the latter as likely portals from the inner ear to the meninges. Since all tympanic membranes were intact and 3 were histologically normal, this silent route of infection warrants medical vigilance.
Linear and nonlinear properties of photonic crystal fibers filled with nematic liquid crystals
Authors: Brzdąkiewicz K. , Laudyn U. , Karpierz M. , Woliński T. , Wójcik J.
Published: November 2006

We investigate linear and nonlinear light propagation in the photonic crystal fibers infiltrated with nematic liquid crystals. Such a photonic structure, with periodic modulation of refractive index, which could be additionally controlled by the temperature and by the optical power, allows for the study of discrete optical phenomena. Our theoretical investigations, carried out with the near infrared wavelength of 830 nm, for both focusing and defocusing Kerr-type nonlinearity, show the possibility of the transverse light localization, which can result in the discrete soliton generation. In addition, we present the preliminary experimental results on the linear light propagation in the photonic crystal fiber with the glycerin-water solution and 6CHBT nematics, as the guest materials.
Formation and dynamics of easy orientation axis in magnetic field on PVCN-F surface
Authors: Buluy O. , Reznikov Y. , Slyusarenko K. , Nobili M. , Reshetnyak V.
Published: November 2006

We describe the experiments on a magnetically-induced drift of the easy axis on a soft surface of photoaligning material fluoro-polyvinyl-cinnamate. We found unexpected partial relaxation of the drift of the easy axis after switching the magnetic field off. This relaxation cannot be explained in a framework of the existing models and requires additional assumptions about the drift process. We propose a model that explains the experimental data suggesting elastic-like behaviour of the polymer fragments during the drift of the easy axis.