bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oestrogen and Testosterone Modulate the Firing Activity of Dorsal Raphe Nucleus Serotonergic Neurones in Both Male and Female Rats
Authors: Robichaud M. , Debonnel G. 
Published: March 2005

AbstractWomen are twice as likely to suffer from mood disorders than men. Moreover, a growing body of evidence suggests a reciprocal modulation between sex steroids and the serotonin (5‐HT) system. A previous study from our laboratory has shown that the progesterone metabolites 5β‐pregnane‐3,20‐dione (5β‐DHP) and 5α‐pregnan‐3α‐ol,20‐one (3α,5α‐THP), as well as dehydroepiandrosterone (DHEA), increase the firing activity of dorsal raphe nucleus (DRN) 5‐HT neurones in female rats. The present study was undertaken to assess the effects of these steroids in male rats, as well as the effects of testosterone and 17β‐oestradiol (17β‐E) in both sexes, and finally to evaluate gender differences in the modulation of the 5‐HT neuronal firing activity by these different neuroactive steroids. Male rats were treated i.c.v., for 7 days, with a dose of 50 µg/kg/day of one of the following steroids: progesterone, 5β‐DHP, 3α,5α‐THP, DHEA, testosterone, 17β‐hydroxy‐5α‐androstan‐3‐one (5α‐DHT) and 17β‐E. Some rats also received a 3‐day administration of testosterone (50 µg/kg/day, i.c.v). Females were treated in the same fashion with testosterone and 17β‐E. Extracellular unitary recordings of 5‐HT neurones, obtained in vivo in the DRN of these rats, revealed that testosterone and 17β‐E increased the firing activity of 5‐HT neurones in both males and females. In males, the effect of testosterone could already be seen after 3 days of treatment. Neither castration nor any treatment with other steroids significantly modified the firing rate of male 5‐HT neurones. Taken together with previous findings, the results of the present study indicate both similarities and differences between sexes in the modulation of 5‐HT neurones by some steroids. This could prove important in understanding gender differences in mood disorders.
The unique structure of archaeal ‘hami’, highly complex cell appendages with nano‐grappling hooks
Authors: Moissl Christine , Rachel Reinhard , Briegel Ariane , Engelhardt Harald , Huber Robert 
Published: March 2005

SummaryProteinaceous, hair‐like appendages known as fimbriae or pili commonly extend from the surface of prokaryotic cells and serve important functions such as cell adhesion, biofilm formation, motility and DNA transfer. Here we show that a novel group of archaea from cold, sulphidic springs has developed cell surface appendages of an unexpectedly high complexity with a well‐defined base‐to‐top organization. It represents a new class of filamentous cell appendages, for which the term ‘hamus’ is proposed. Each archaeal cell is surrounded by a halo of about 100 hami, which mediate strong adhesion of the cells to surfaces of different chemical composition. The hami are mainly composed of 120 kDa subunits and remained stable in a broad temperature and pH range (0–70°C; 0.5–11.5). Electron microscopy and cryo‐electron tomography revealed that the hamus filament possesses a helical basic structure. At periodic distances, three prickles emanate from the filament, giving it the character of industrially produced barbwire. At its distal end the hami carry a tripartite, barbed grappling hook (60 nm in diameter). The architecture of this molecular hook is reminiscent of man‐made fishhooks, grapples and anchors. It appears that nature has developed a perfect mechanical nano‐tool in the course of biological evolution, which also might prove useful in the field of nanobiotechnology.
Co‐regulation of Salmonella enterica genes required for virulence and resistance to antimicrobial peptides by SlyA and PhoP/PhoQ
Authors: Navarre William Wiley , Halsey Thomas A. , Walthers Don , Frye Jonathan , McClelland Michael , Potter Jennifer L. , Kenney Linda J. , Gunn John S. , Fang Ferric C. , Libby Stephen J. 
Published: March 2005

SummaryAnalysis of the transcriptome of slyA mutant Salmonella enterica serovar Typhimurium revealed that many SlyA‐dependent genes, including pagC, pagD, ugtL, mig‐14, virK, phoN, pgtE, pipB2, sopD2, pagJ and pagK, are also controlled by the PhoP/PhoQ regulatory system. Many SlyA‐ and PhoP/PhoQ‐co‐regulated genes have functions associated with the bacterial envelope, and some have been directly implicated in virulence and resistance to antimicrobial peptides. Purified His‐tagged SlyA binds to the pagC and mig‐14 promoters in regions homologous to a previously proposed ‘SlyA‐box’. The pagC promoter lacks a consensus PhoP binding site and does not bind PhoP in vitro, suggesting that the effect of PhoP on pagC transcription is indirect. Stimulation of pagC expression by PhoP requires SlyA. Levels of SlyA protein and mRNA are not significantly changed under low‐magnesium PhoP‐inducing conditions in which pagC expression is profoundly elevated, however, indicating that the PhoP/PhoQ system does not activate pagC expression by altering SlyA protein concentration. Models are proposed in which PhoP may control SlyA activity via a soluble ligand or SlyA may function as an anti‐repressor to allow PhoP activation. The absence of almost all SlyA‐activated genes from the Escherichia coli K12 genome suggests that the functional linkage between the SlyA and PhoP/PhoQ regulatory systems arose as Salmonella evolved its distinctive pathogenic lifestyle.
Influence of Water Stress on the Chemical Composition of Seeds of Two Lupins (Lupinus albus and Lupinus mutabilis)
Authors: Carvalho I. S. , Chaves M. , Pinto Ricardo C. 
Published: March 2005

AbstractWe have performed chemical proximate analysis and determined the carbohydrate profile of mature seeds of Lupinus albus, cv. Rio Maior and Lupinus mutabilis, cv. Potosi plants, either well watered (ww) or subjected to a water‐stress period (imposed from the 15th to 35th day after anthesis). Protein content from lupin seeds was 450 and 320 g kg−1 of seed on dry weight basis, for ww plants, respectively, of L. albus and L. mutabilis. Water stress did not affect protein content. The oil content of ww plants was about 120 g kg−1 of seed dry weight for L. albus and 180 g kg−1 of seed dry weight for L. mutabilis. Water stress reduced those values of half. The sugar content was about 90 g kg−1 for L. albus and 50 g kg−1 of seed dry weight for L. mutabilis, in ww plants. Water stress led to an increase in sugar content to 200 and 130 g kg−1 of seed dry weight, respectively, for L. albus and L. mutabilis. The α‐galactosides amounted to 70 % of the total sugars (raffinose being 30 % and stachyose, 40 %) and sucrose was about 20 % of the total sugars. Water stress increased total carbohydrates and increased the sucrose/α‐galactoside ratio, although reducing raffinose content and increasing sucrose content.
Seed Priming Increases Crop Yield Possibly by Modulating Enzymes of Sucrose Metabolism in Chickpea
Authors: Kaur S. , Gupta A. K. , Kaur N. 
Published: March 2005

AbstractThe number of seeds and seed yield per plant were higher in chickpea crops raised from water and mannitol (4 %) primed seeds in comparison with the control non‐primed crops. In primed plants, an enhanced acid invertase activity in the apical part of the main stem and the part immediately below it at 100 and 130 days after sowing (DAS) might result in an increased availability of hexoses to these plant parts. In addition, decreased acid invertase activity at the point of initiation of branches and in the internodes of stem observed in primed plants indicated restricted hydrolysis of sucrose during its transport through the stem, resulting in its more supply to the actively growing sinks. The activities of sucrose‐cleaving enzymes, i.e. invertase and sucrose synthase (SS) in podwall of primed plants were higher at 110 DAS. At 140 DAS, a stage of rapid seed filling, increased activities of SS and sucrose phosphate synthase (SPS) were observed in seeds of primed plants. Increased SPS activity in seeds of primed crop could meet the increased assimilate requirements of the developing seeds. Higher activity of SS in seeds of primed crop may facilitate seed filling. These data suggest that enzymes of sucrose metabolism play an important role in increasing the yield of chickpea crops raised from primed seeds.
Alternate Row Spacing and Plant Density Effects on Forage and Dry Matter Yield of Corn Hybrids (Zea mays L.)
Authors: Turgut I. , Duman A. , Bilgili U. , Acikgoz E. 
Published: March 2005

AbstractIrrigated field experiments were conducted in the Marmara region of Turkey in 2002 and 2003 to compare alternate 40 : 25 cm row spacings and conventional 65 cm with four different plant densities (65 000, 85 000, 105 000 and 125 000 plants ha−1) of three corn hybrids (DK‐585, ADA 95–10 and C‐955) in some morphological traits and forage and dry matter yield. Morphological traits such as plant height, leaf per plant, stem diameter, ear per plant and ear percentage were measured, forage and dry matter yield was also determined in this study. Hybrids, row spacings and plant densities significantly affected some morphological traits, forage and dry matter yield at 0.01 level. Later maturing hybrids tended to produce taller and thicker stemmed plants. Row spacings and plant densities did not affect plant height. Average stem diameter increased significantly with population density. Row spacings did not influence leaf number, whereas leaf number increased slightly with plant density. On average, all corn plants had slightly more than 1.0 ear per plant in our experiment. Row spacings and plant densities did not affect significantly number of ear per plant. Early maturing DK‐585 had the highest ear percentage whilst late maturing C‐955 lowest. Yields usually increased with hybrid maturity. When averaged across years, row spacings and plant densities, late maturing C‐955 performed significantly better in forage and dry matter yield in all experimental years and combined years. The studies showed favourable advantage for alternate 40 : 25 cm rows over conventional 65 cm row spacings at all plant densities. Average forage and dry matter yields were greater for alternate 40 : 25 cm row spacings than for 65 cm row spacings. However, strong hybrid × row spacing interactions for both forage and dry matter yield were detected.
Stimulation through electrodes implanted near the subthalamic nucleus activates projections to motor areas of cerebral cortex in patients with Parkinson's disease
Authors: MacKinnon Colum D. , Webb Ruth M. , Silberstein Paul , Tisch Steven , Asselman Peter , Limousin Patricia , Rothwell John C. 
Published: March 2005

AbstractHigh‐frequency electrical stimulation through electrodes implanted in the subthalamic nucleus (STN) has been shown to reduce significantly the cardinal symptoms of Parkinson's disease (PD). Despite the success of this treatment, the mechanisms of action of stimulation are poorly understood. To elucidate further the mechanisms of action of deep brain stimulation and its effects on cortical activity, we recorded electroencephalographic potentials from 61 scalp‐surface electrodes during low‐frequency (5–10 Hz) bipolar stimulation in 11 patients with advanced PD (14 implanted electrodes were tested). In all electrodes tested, stimulation through at least one of the four contacts produced a medium‐latency waveform with an average onset of 14 ± 3 ms and peak at 23 ± 4 ms. This potential typically increased in magnitude across contacts from ventral to dorsal. Within‐subject comparisons of median nerve somatosensory evoked potentials demonstrated that the generator of the medium‐latency potential was within the primary sensorimotor cortex or lateral premotor cortex ipsilateral to stimulation. The timing and topography of this potential were consistent with indirect activation of the cortex by excitation of pallido‐thalamic axons that traverse the dorsal aspect of the STN. The potential evoked by stimulation through the contact used for optimal clinical effect was highly variable across electrodes and frequently different from the medium‐latency potential described above, suggesting that the neuronal elements mediating the medium‐latency potential were different from those that mediate the clinical effects.
Type grouping in skeletal muscles after experimental reinnervation: another explanation
Authors: Vleggeert‐Lankamp C. L. A. M. , De Ruiter G. C. W. , Wolfs J. F. C. , Pêgo A. P. , Feirabend H. K. P. , Lakke E. A. J. F. , Malessy M. J. A. 
Published: March 2005

AbstractType grouping signifies clustering of muscle fibres of the same metabolic type, and is a frequent finding in reinnervated muscles. To elucidate the mechanism behind it, the rat sciatic nerve was either autografted or grafted with hollow synthetic nerve grafts. Twelve weeks later the number and fibre area of the type I and type II muscle fibres in the gastrocnemic and anterior tibial muscles were determined after ATP‐ase staining. The number and diameter of peroneal nerve fibres distal to the grafts were measured, and the number of Aα‐nerve fibres was derived. Nearly all nerve and muscle morphometrical parameters changed equally in both experimental groups. However, type grouping occurred frequently only after autografting, whereas the number of nerve fibres and the number of Aα‐nerve fibres increased in this group. Hence type grouping cannot be explained by increased intramuscular sprouting subsequent to a decrease in the number of innervating nerve fibres, as previously presumed. Regenerating axons branch along their course through the peripheral nerve. We propose that the probability of the occurrence of type grouping is related to the dispersion of sibling branches in the nerve. In the autograft, emerging branches are kept together by Schwann cell basal lamina scaffolds, in contrast to the hollow synthetic nerve grafts where the emerging branches become dispersed. Thus, in muscles reinnervated after autografting, the probability that nerve branches that arrive at a specific muscle territory are sibling branches is greater than after hollow tube grafting. Consequently, the probability that type grouping will occur is greater.
NR2 to NR3B subunit switchover of NMDA receptors in early postnatal motoneurons
Authors: Fukaya Masahiro , Hayashi Yasunori , Watanabe Masahiko 
Published: March 2005

AbstractThe NR3B NMDA receptor subunit is selective to somatic motoneurons in the adult nervous system. Here we report its developmental expression in the mouse brain and spinal cord by in situ hybridization. NR3B mRNA was detected in few neural regions during embryonic and neonatal periods. It first appeared in motoneurons at postnatal day (P)10−P14, and attained the maximal level at P21 and adult stage. This developmental profile was reciprocal with that of NR2 subunits, of which NR2A mRNA was most predominant in embryonic and neonatal motoneurons and downregulated by P14. Interestingly, mRNA of the NR1 subunit, which is required for functional NMDA receptors, displayed a ‘V’‐shaped change, decreasing with the early postnatal decline of NR2 mRNAs and increasing with the subsequent appearance of NR3B mRNA. Therefore, the major regulatory subunit of NMDA receptors is likely to switch from NR2 to NR3B in somatic motoneurons during the early postnatal period.
A single time‐window for protein synthesis‐dependent long‐term memory formation after one‐trial appetitive conditioning
Authors: Fulton Daniel , Kemenes Ildiko , Andrew Richard J. , Benjamin Paul R. 
Published: March 2005

AbstractProtein synthesis is generally held to be essential for long‐term memory formation. Often two periods of sensitivity to blockade of protein synthesis have been described, one immediately after training and another several hours later. We wished to relate the timing of protein synthesis‐dependence of behavioural long‐term memory (LTM) formation to an electrophysiological correlate of the LTM memory trace. We used the snail Lymnaea because one‐trial appetitive conditioning of feeding using a chemical conditioned stimulus leads to a stable LTM trace that can be monitored behaviourally and then electrophysiologically in preparations made from the same animals. Anisomycin (an inhibitor of translation) injected 10 min after training blocked behavioural LTM formation. Actinomycin D (an inhibitor of transcription) was also effective at 10 min. When anisomycin, at doses shown to be effective in blocking central nervous system protein synthesis, was injected at 1, 2, 3, 4, 5 and 6 h after training there was no effect on recall. These results indicate that there is a single period of sensitivity to protein synthesis inhibition in Lymnaea lasting for between 10 min and 1 h after training with no evidence for a second window of sensitivity. An electrophysiological correlate of LTM was found to be sensitive to anisomycin injected 10 min after training. It is unusual to find only one period of protein synthesis‐dependence in detailed time‐course studies of LTM, and this suggests that the consolidation processes involving protein synthesis are relatively rapid in one‐trial appetitive conditioning and complete within 1 h of training.
Dopamine depletion increases the power and coherence of β‐oscillations in the cerebral cortex and subthalamic nucleus of the awake rat
Authors: Sharott Andrew , Magill Peter J. , Harnack Daniel , Kupsch Andreas , Meissner Wassilios , Brown Peter 
Published: March 2005

AbstractLocal field potentials (LFPs) recorded from the subthalamic nucleus (STN) of untreated patients implanted with stimulation electrodes for the treatment of Parkinson's disease (PD) demonstrate strong coherence with the cortical electroencephalogram over the β‐frequency range (15–30 Hz). However, studies in animal models of PD emphasize increased temporal coupling in cortico‐basal ganglia circuits at substantially lower frequencies, undermining the potential usefulness of these models. Here we show that 6‐hydroxydopamine (6‐OHDA) lesions of midbrain dopamine neurons are associated with significant increases in the power and coherence of β‐frequency oscillatory activity present in LFPs recorded from frontal cortex and STN of awake rats, as compared with the healthy animal. Thus, the pattern of synchronization between population activity in the STN and cortex in the 6‐OHDA‐lesioned rodent model of PD closely parallels that seen in the parkinsonian human. The peak frequency of coherent activity in the β‐frequency range was increased in lesioned animals during periods of spontaneous and sustained movement. Furthermore, administration of the dopamine receptor agonist apomorphine to lesioned animals suppressed β‐frequency oscillations, and increased coherent activity at higher frequencies in the cortex and STN, before producing the rotational behaviour indicative of successful lesion. Taken together, these results support a crucial role for dopamine in the modulation of population activity in cortico‐basal ganglia circuits, whereby dopaminergic mechanisms effectively filter out synchronized, rhythmic activity at β‐frequencies at the systems level, and shift temporal couplings in these circuits to higher frequencies. These changes may be important in regulating movement.
The novel cytosolic RING finger protein dactylidin is up‐regulated in brains of patients with Alzheimer's disease
Authors: Von Rotz Ruth C. , Kins Stefan , Hipfel Rainer , Von Der Kammer Heinz , Nitsch Roger M. 
Published: March 2005

AbstractAlzheimer's disease (AD) is characterized by a progressive degeneration of neurons along with deposition of amyloid plaques and the formation of neurofibrillary tangles. Neurodegeneration in AD follows both a spatial pattern of selective vulnerability and temporal staging of affected neurons. In order to address transcriptional changes associated with this selective vulnerability, we used subtractive hybridization of transcripts derived from human frontal cortex, which degenerates in late stages of AD, against transcripts of the inferior temporal cortex, which is affected both heavily and early in the course of AD. Moreover, we compared these to brain sections obtained from age‐matched control subjects. We isolated a differentially expressed novel gene encoding a polypeptide that contained an amino‐terminal C3HC4 RING finger domain, called dactylidin. It is ubiquitously expressed in all tissues examined and in situ hybridization of mouse brain sections revealed specific expression in neurons. Further, heterologous expression studies revealed a cytoplasmic localization of dactylidin and as all known cytoplasmic RING finger proteins function as ubiquitin protein ligases, an E3‐like ligase function of dactylidin is probable. However, the up‐regulation of dactylidin in highly vulnerable brain tissues of AD patients was confirmed by a quantitative PCR approach, suggesting that dactylidin may function early in the progression of neurodegenerative diseases.
Prostate‐specific antigen (PSA) complexed to α1‐antichymotrypsin improves prostate cancer detection using total PSA in Japanese patients with total PSA levels of 2.0–4.0 ng/mL
Authors: Kobayashi Takashi , Kamoto Toshiyuki , Nishizawa Koji , Mitsumori Kenji , Ogura Keiji , Ide Yoshihiro 
Published: March 2005

OBJECTIVETo assess the utility of prostate‐specific antigen (PSA) complexed to α1‐antichymotrypsin (PSA‐ACT) in prostate cancer screening in Japanese men with a total PSA level of 2.0–4.0 ng/mL, as improving cancer detection in men with these total PSA levels is a challenge for clinical urologists.PATIENTS AND METHODSTotal PSA and PSA‐ACT were prospectively assessed and prostate biopsy recommended for patients who met either of two thresholds, i.e. a total PSA of ≥ 2.0 ng/mL or a PSA‐ACT of ≥ 1.5 ng/mL. The diagnostic ability of total PSA and PSA‐ACT, and free‐to‐total PSA ratio and prostate volume‐adjusted density were evaluated by receiver operating characteristic (ROC) analysis.RESULTSOf 1003 men enrolled, 547 met the biopsy criteria and a biopsy was taken in 315 (57.6%) patients. The area under the ROC curve for PSA‐ACT (0.679) was significantly greater than that for total PSA (0.601, P = 0.04) and equivalent to that for the free‐to‐total ratio (0.686, P = 0.911) in 116 men, including 27 with cancer with total PSA levels of 2.0–4.0 ng/mL. PSA‐ACT was more specific than the free‐to‐total ratio at a sensitivity of 95% (36% vs 18%, P < 0.05). The best variable for discriminating between cancer and benign disease in men with PSA levels of 2.0–4.0 ng/mL was PSA‐ACT density (area under the curve 0.852) which provided 66% specificity at a sensitivity of 90%.CONCLUSIONSPSA‐ACT is better than total PSA and equivalent to the free‐to‐total ratio for detecting prostate cancer in men with PSA levels of 2.0–4.0 ng/mL, and is thus useful for reducing the number of unnecessary biopsies.