bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamics of photosynthetic pigments in an Andean lake in Colombia
Authors: Zapata‐Anzola Angela M. , Rivera‐Rondón Carlos A. , Donato‐Rondón Jhon Ch. 
Published: March 2006

AbstractGuatavita Lake is a small, sheltered tropical high mountain lake located in the Colombian Andes, with a closed watershed and a maximum depth of 25 m. It is the freshwater source for human consumption in nearby small towns, as well as being a site of cultural value for the country, as it was a sacred place to indigenous peoples until about five centuries ago. As the structure and function of this aquatic ecosystem is poorly understood, this study provides initial knowledge on its phytoplankton biomass dynamics, which should be useful in designing efficient management plans with environmental baseline information for similar lakes elsewhere. Physical and chemical data, and photosynthetic pigment concentrations, were measured for the period November 1999–November 2000 at the central vertical axis of Guatavita Lake. The vertical profile of the chlorophyll‐a concentration was closely related to the dissolved inorganic nitrogen concentrations and the thermal stratification characteristics. The maximum chlorophyll‐a concentration in the metalimnion was recorded for the thermal stratification period (November 1999–June 2000). Deepening of the maximum chlorophyll‐a concentration began in February, continuing to June, when it reached its lowest value at the 15 m depth. The phytoplankton biomass values showed an increment within the entire water column at the beginning of the mixing period (July). The relation between the metalimnetic peak of chlorophyll‐a and the dissolved inorganic nitrogen concentration suggests the growth of the phytoplankton community is limited mainly by the availability of nitrogen.
Restoration scheme for macrophytes in a hypertrophic water body, Wuli Lake, China
Authors: Jin Xiangcan , Xu Qiujin , Yan Changzhou 
Published: March 2006

AbstractThis report analyses the relevant factors that influence the restoration of macrophytes in hypertrophic water bodies, including hydrology, water quality and sediment. Wuli Lake in China is used as a case study for the goal of achieving limno‐ecosystem protection and sustainable development. This report also identifies and discusses some potential macrophyte restoration measures, including pollution control at the source and reducing external pollutant loads to the lake, and environmental restoration measures to improve lake water quality and sediment conditions. The potential for the sustainable management of the lake ecosystem also was explored from the perspective of new restoration systems and mechanisms.
Dendritic amplification of inhibitory postsynaptic potentials in a model Purkinje cell
Authors: Solinas Sergio M. G. , Maex Reinoud , De Schutter Erik 
Published: March 2006

AbstractIn neurons with large dendritic arbors, the postsynaptic potentials interact in a complex manner with active and passive membrane properties, causing not easily predictable transformations during the propagation from synapse to soma. Previous theoretical and experimental studies in both cerebellar Purkinje cells and neocortical pyramidal neurons have shown that voltage‐dependent ion channels change the amplitude and time‐course of postsynaptic potentials. We investigated the mechanisms involved in the propagation of inhibitory postsynaptic potentials (IPSPs) along active dendrites in a model of the Purkinje cell. The amplitude and time‐course of IPSPs recorded at the soma were dependent on the synaptic distance from the soma, as predicted by passive cable theory. We show that the effect of distance on the amplitude and width of the IPSP was significantly reduced by the dendritic ion channels, whereas the rise time was not affected. Somatic IPSPs evoked by the activation of the most distal synapses were up to six times amplified owing to the presence of voltage‐gated channels and the IPSP width became independent of the covered distance. A transient deactivation of the Ca2+ channels and the Ca2+‐dependent K+ channels, triggered by the hyperpolarization following activation of the inhibitory synapse, was found to be responsible for these dynamics. Nevertheless, the position of activated synapses had a marked effect on the Purkinje cell firing pattern, making stellate cells and basket cells most suitable for controlling the firing rate and spike timing, respectively, of their target Purkinje cells.
Axon guidance during establishment of electroreceptor innervation in the catfish Kryptopterus
Authors: Roth Anton 
Published: March 2006

AbstractThe principles were studied, according to which the characteristic electroreceptor distribution pattern consisting of organ rows and clusters on the tail of the catfish Kryptopterus spec. is formed. As each electroreceptor is induced by its future afferent (‘electrosensory’) nerve fibre at the site where the outgrowing fibre reaches the epidermis, it is the fibre navigation which controls the organ distribution. Three navigation principles of the outgrowing electrosensory fibres were found. (i) The electrosensory fibre courses are bound to the tail segmentation. Nerve displacement experiments suggest that the fibres are guided by the intersegmental connective tissue sheaths, i.e. the myosepta and myocommata. (ii) The individual fibres have no specificity for a certain route or target area on the tail, but can grow in any direction and into any tail area and induce organs there. This is indicated by experiments with nerve elimination and nerve deflection. (iii) An outgrowing fibre's only orientation is towards a nearby ‘free site’; i.e. it aims for a place in clusters with fewer organs than their actual capacity allows. The capacity increases continuously with the specimen's age, so that free sites progressively develop. So, it depends on chance which outgrowing fibre occupies which ‘free site’; a free site is targeted by whatever outgrowing fibre happens to be the nearest. The mechanisms of development of the somatotopic projection of the electrosensory fibres to the central nervous system (CNS) are discussed.
Hippocampal vulnerability following traumatic brain injury: a potential role for neurotrophin‐4/5 in pyramidal cell neuroprotection
Authors: Royo N. C. , Conte V. , Saatman K. E. , Shimizu S. , Belfield C. M. , Soltesz K. M. , Davis J. E. , Fujimoto S. T. , McIntosh T. K. 
Published: March 2006

AbstractTraumatic brain injury (TBI) causes selective hippocampal cell death, which is believed to be associated with cognitive impairment observed both in clinical and experimental settings. Although neurotrophin administration has been tested as a strategy to prevent cell death following TBI, the potential neuroprotective role of neurotrophin‐4/5 (NT‐4/5) in TBI remains unknown. We hypothesized that NT‐4/5 would offer neuroprotection for selectively vulnerable hippocampal neurons following TBI. Measurements of NT‐4/5 in rats subjected to lateral fluid percussion (LFP) TBI revealed two–threefold increases in the injured cortex and hippocampus in the acute period (1–3 days) following brain injury. Subsequently, the response of NT‐4/5 knockout (NT‐4/5–/–) mice to controlled‐cortical impact TBI was investigated. NT‐4/5–/– mice were more susceptible to selective pyramidal cell loss in Ahmon's corn (CA) subfields of the hippocampus following TBI, and showed impaired motor recovery when compared with their brain‐injured wild‐type controls (NT‐4/5wt). Additionally, we show that acute, prolonged administration of recombinant NT‐4/5 (5 µg/kg/day) prevented up to 50% of the hippocampal CA pyramidal cell death following LFP TBI in rats. These results suggest that post‐traumatic increases in endogenous NT‐4/5 may be part of an adaptive neuroprotective response in the injured brain, and that administration of this neurotrophic factor may be useful as a therapeutic strategy following TBI.
Reparatory effects of nicotine on NMDA receptor‐mediated synaptic plasticity in the hippocampal CA1 region of chronically lead‐exposed rats
Authors: Wang Hui‐Li , Chen Xiang‐Tao , Luo Le , Lou Zhi‐Yi , Wang Shu , Chen Ju‐Tao , Wang Ming , Sun Li‐Guang , Ruan Di‐Yun 
Published: March 2006

AbstractActivation of neuronal nicotinic acetylcholine receptors (nAChRs) modulates the induction of long‐term potentiation (LTP): a possible cellular mechanism of learning. To investigate the effect of nicotine on synaptic plasticity in chronically lead‐exposed rats, field excitatory postsynaptic potentials and paired‐pulse facilitation (PPF) were recorded in the CA1 area of hippocampal slices from chronically lead‐exposed 23–30‐day‐old rats. The results showed the following. (1) Nicotine (1 µm) facilitated the induction of LTP in CA1 by a weak tetanic stimulation (100 Hz, 20 pulses), which does not by itself produce LTP in lead‐exposed rats. This effect was significantly suppressed by mecamylamine, a nicotinic antagonist, suggesting that the facilitation of LTP was through nAChRs. (2) The nicotine‐facilitated LTP was blocked by dihydro‐β‐erythroidine (DHβE), a non‐α7 nAChR antagonist, whereas long‐term depression (LTD) was produced by the combination of nicotine and methyllycaconitine, a α7‐nAChR antagonist. This type of LTD was blocked by DHβE. This suggested that several nAChR subtypes were involved in the nicotine‐facilitated synaptic plasticity. (3) Nicotine enhanced PPF in the hippocampal CA1 region, and the nicotine‐facilitated LTP in lead‐exposed rats was blocked by eitherd‐(–)‐2‐amino‐5‐phosphonopentanoic acid, theN‐methyl‐d‐aspartate (NMDA) receptor antagonist, or picrotoxin, an antagonist of γ‐aminobutyric acidAreceptors. We suggest that nicotine‐facilitated synaptic plasticity was due to the activation of NMDARs by disinhibition of pyramidal cells through presynaptic nAChRs. This may represent the cellular basis of nicotine‐facilitated cognitive enhancement observed in chronically lead‐exposed rats.
The value of a second transurethral resection for T1 bladder cancer
Authors: SCHWAIBOLD HARTWIG E. , SIVALINGAM SIVAPRAKASAM , MAY FLORIAN , HARTUNG RUDOLF 
Published: March 2006

OBJECTIVETo evaluate a series of repeat transurethral resections (TURs) of tumour in patients with T1 bladder cancer, usually used to ensure a complete resection and to exclude the possibility muscle‐invasive disease.PATIENTS AND METHODSIn all, 136 consecutive patients had a second TUR because of a histopathological diagnosis of T1 transitional cell carcinoma (TCC) after their initial TUR. Of the 136 patients, 101 were first presentations and 35 had recurrent tumours. The second TUR was done 4–6 weeks later. The evaluation included the presence of previously undetected residual tumour, changes to histopathological staging/grading, and tumour location.RESULTSIn all, 71 patients (52%) had residual disease according to findings from specimens obtained during the second TUR. The staging was: no tumour, 65 (48%); Ta, 11 (8%); T1, 32 (24%); Tis, 15 (11%); and ≥ T2, 13 (10%). Histopathological changes that worsened the prognosis (>T1 and or concomitant Tis) were found in 21% of patients. Residual malignant tissue was found in the same location as the first TUR in 86% of the patients, and at different locations in 14%. Overall, 28 patients (21% of the original 136) had a radical cystectomy as a consequence of the second TUR findings.CONCLUSIONSA routine second TUR should be advised in patients with T1 TCC of the bladder, to achieve a more complete tumour resection and to identify patients who should have a prompt cystectomy.
A re‐staging transurethral resection predicts early progression of superficial bladder cancer
Authors: HERR HARRY W. , DONAT S. MACHELE 
Published: March 2006

OBJECTIVETo determine whether pathology on a re‐staging transurethral resection (TUR) predicts the early progression of superficial bladder cancer.PATIENTS AND METHODSIn all, 710 patients presenting with multiple superficial bladder cancers were evaluated by re‐staging TUR and followed for 5 years. Tumours were classified by stage as confined to mucosa (Ta) or invading submucosa (T1), and by grade (low‐ or high‐grade). Pathology on re‐staging TUR was correlated with the endpoints of tumour recurrence and stage progression.RESULTSOf the 710 patients, 490 (69%) had a recurrence and 149 (21%) progressed over 5 years. Eighty patients had high‐grade invasive (T1G3) cancer on re‐staging TUR and 61 (76%) progressed to muscle invasion (median time to progression 15 months), compared with 88 of 630 (14%) who had no evidence of tumour (T0) or other than T1 tumours detected on re‐staging TUR.CONCLUSIONA re‐staging TUR identifies patients with superficial bladder cancer who are at high risk of early tumour progression.
Using prostate‐specific antigen screening and nomograms to assess risk and predict outcomes in the management of prostate cancer
Authors: HAMMERER PETER G. , KATTAN MICHAEL W. , MOTTET NICOLAS , PRAYER‐GALETTI TOMMASO 
Published: March 2006

In this section there are two reviews concerning prostate cancer, both from the same group of authors. In the first, they describe the combination of nomograms with PSA screening to assess risk and to predict outcomes in the management of prostate cancer. In the second, they indicate how outcomes and quality of life can be optimised in the hormonal treatment of prostate cancer.Botulinum toxin has become very popular in the management of a whole range of conditions both inside and outside the urinary tract. Now it has been extended to prostatic disorders, and the mini‐review presented here has evaluated reports and the authors’ personal experience in the mechanisms of action and clinical efficacy of Botulinum toxin in the prostate.Finally, there is a mini‐review of FISH in bladder cancer, particularly its development, applications, and its potential for the future.We review the role of prostate‐specific antigen (PSA) and the importance of patient education in the management of prostate cancer, based on discussions held at a European symposium on managing prostate cancer. Although PSA is the most widely used serum marker for detecting prostate cancer and for monitoring treatment responses, its use as a diagnostic marker is controversial due to concerns of over‐diagnosis and low specificity. PSA isoforms, as well as PSA doubling time, might improve the specificity for earlier prostate cancer detection and can be used as surrogate markers for treatment efficacy. Patients can differ considerably in the importance they place on health‐related quality of life aspects and fear of cancer progression. Consequently, there needs to be active, educated discussion of risk and outcomes between physicians and patients. Risk assessment tools, e.g. validated nomograms, enable clinicians to improve their decision analysis and form the basis for subsequent discussion of treatment options between the physician and patient, thereby enabling informed consent and appropriate decision‐making.
Locating Impropriety: Street Drinking, Moral Order, and the Ideological Dilemma of Public Space
Authors: Dixon John , Levine Mark , McAuley Rob 
Published: March 2006

Drawing on research in urban sociology, cultural geography, and social psychology, this paper explores some of the moral rules that govern social relations in public places. In particular, we consider how certain practices become classified as everyday incivilities—infractions of the moral order that sustains public life. In order to develop this notion, we draw illustrations from an ongoing research project that is investigating social attitudes towards “street drinking,” an activity that has led to the creation of “alcohol‐free zones” in over 100 British cities during the past decade. As an emergent theme, this research has suggested that the classification of street drinking as either acceptable or unacceptable conduct is contingent upon the social construction of public space that users invoke. This theme is discussed in the context of wider struggles over citizenship and social control in the public domain—struggles manifest within “ideological dilemmas” (Billig et al., 1988) over the limits of free conduct, the tension between open and closed public spaces, and the attempt to distinguish “admissible” from “inadmissible” publics.
On the reading and interpretation of the month‐line in the gothic calendar1
Authors: Landau David 
Published: March 2006

AbstractUsing a digital image processing method I demonstrate that a reading from 1833 of the month‐line of the Gothic calendar is incorrect. According to that reading, the line includes the word Naubaimbair‘November’, in addition to fruma jiuleis ·l·. In this article I endeavour to demonstrate that there is no Naubaimbair in the original manuscript.
Post‐verbal subjects in early east slavonic
Authors: Turner Sarah 
Published: March 2006

AbstractIn Contemporary Standard Russian (CSR) the subject typically appears before the verb (SV order). The high proportion of clauses in which the verb appears before the subject (VS order) in some early medieval sources of East Slavonic provenance is striking by comparison. This paper investigates the phenomenon against the background of the complex linguistic situation of the period. It uses the concepts of Functional Sentence Perspective (FSP) as set out in the Academy Grammar of Russian (Kovtunova 1980: 190–214) as basic tools for analysis and finds that, with a slight expansion of one of its central ideas, FSP can account for many of the VS orders in the medieval material. It suggests that clause patterns which resist interpretation in these terms can be understood as features characteristic of the different text types proposed by Benveniste (1966: 238–42) and Weinrich (1971).
Horizontal advancement flap for lateral dorsal nasal defects
Authors: Ascari‐Raccagni A , Righini MG 
Published: March 2006

AbstractBackground  Repairing dorsal nasal defects is a frequent challenge for dermatologic surgeons, mainly due to the high frequency of basal cell carcinomas on this site. Obvious scars, mismatched skin and distortion of the nasal contour are the surgical hazards that must be avoided in these cases.Aim  Our aim was to perform surgery involving a simple flap in order to repair medium to large defects on the dorsal side of the nose.Methods  The dorsal horizontal advancement flap was studied in 12 patients, in order to evaluate the benefits and limits of this surgical procedure.Results  The resulting scars on most of our patients were well‐camouflaged among their natural skin lines, and there was neither distortion of the alar contour nor the nostril.Conclusions  This flap is easy to perform and, in selected cases, provides an outstanding alternative to second‐intention healing, full‐thickness skin grafts, transposition, rotation and pedicle flaps.
Stevens–Johnson syndrome in two patients treated with cranial irradiation and phenytoin
Authors: Aydin F , Cokluk C , Senturk N , Aydin K , Canturk MT , Turanli AY 
Published: March 2006

AbstractStevens‐Johnson syndrome (SJS) is a severe cutaneous eruption that most often appears as an adverse reaction to medication. In this report, we present two patients diagnosed with SJS, which developed in patients with brain tumour, after receiving cranial irradiation and phenytoin. Concomitant application of these two therapies may play an important role in the occurrence of the disease.
Calorie restriction mimetics: an emerging research field
Authors: Ingram Donald K. , Zhu Min , Mamczarz Jacek , Zou Sige , Lane Mark A. , Roth George S. , DeCabo Rafael 
Published: March 2006

SummaryWhen considering all possible aging interventions evaluated to date, it is clear that calorie restriction (CR) remains the most robust. Studies in numerous species have demonstrated that reduction of calories 30–50% below ad libitum levels of a nutritious diet can increase lifespan, reduce the incidence and delay the onset of age‐related diseases, improve stress resistance, and decelerate functional decline. A current major focus of this research area is whether this nutritional intervention is relevant to human aging. Evidence emerging from studies in rhesus monkeys suggests that their response to CR parallels that observed in rodents. To assess CR effects in humans, clinical trials have been initiated. However, even if results from these studies could eventually substantiate CR as an effective pro‐longevity strategy for humans, the utility of this intervention would be hampered because of the degree and length of restriction required. As an alternative strategy, new research has focused on the development of ‘CR mimetics’. The objective of this strategy is to identify compounds that mimic CR effects by targeting metabolic and stress response pathways affected by CR, but without actually restricting caloric intake. For example, drugs that inhibit glycolysis (2‐deoxyglucose), enhance insulin action (metformin), or affect stress signaling pathways (resveratrol), are being assessed as CR mimetics (CRM). Promising results have emerged from initial studies regarding physiological responses which resemble those observed in CR (e.g. reduced body temperature and plasma insulin) as well as protection against neurotoxicity (e.g. enhanced dopamine action and up‐regulated neurotrophic factors). Ultimately, lifespan analyses in addition to expanded toxicity studies must be accomplished to fully assess the potential of any CRM. Nonetheless, this strategy clearly offers a very promising and expanding research endeavor.
Thymic output and functionality of the IL‐7/IL‐7 receptor system in centenarians: implications for the neolymphogenesis at the limit of human life
Authors: Nasi Milena , Troiano Leonarda , Lugli Enrico , Pinti Marcello , Ferraresi Roberta , Monterastelli Elena , Mussi Chiara , Salvioli Gianfranco , Franceschi Claudio , Cossarizza Andrea 
Published: March 2006

SummaryDuring aging, the thymus undergoes a marked involution that is responsible for profound changes in the T‐cell compartment. To investigate the capacity of the thymus to produce new cells at the limit of human lifespan, we analyzed some basic mechanisms responsible for the renewal and maintenance of peripheral T lymphocytes in 44 centenarians. Thymic functionality was analyzed by the quantification of cells presenting the T‐cell receptor rearrangement excision circles (TREC). A new method based upon real‐time PCR was used, and we found that most centenarians (84%) had undetectable levels of TREC+ cells. Six‐color cytofluorimetric analysis revealed that centenarians had an extremely low number of naïve T cells; central memory and effector memory T cells were greatly increased, while terminally differentiated cells were as numerous as in young (aged 20–45) or middle‐aged (aged 58–62) donors. Interleukin (IL)‐7 and IL‐7 receptor α‐chain (CD127) levels were the same at all ages, as shown by ELISA, flow cytometry and real‐time PCR. However, IL‐7 plasma levels were higher in centenarian females than males. The presence of TREC+ cells and of very few naïve T lymphocytes suggests that in centenarians such cells could either derive from residues of thymic lymphopoietic islets, or even represent long‐living lymphocytes that have not yet encountered their antigen. IL‐7 could be one of the components responsible, among others, for the higher probability of reaching extreme ages typical of females.