bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pregnancy complicated by multiple pituitary hormone deficiencies
Authors: Fukami Tatsuya , Makino Yasuo , Kawarabayashi Tatsuhiko 
Published: March 2006

AbstractWe report a case of pituitary dwarfism and diabetes insipidus due to pituitary stalk transection in a pregnant Japanese woman, 138 cm in height, born by breech delivery with no evidence of ante‐ or intrapartum asphyxia. The patient had no central nervous disturbance, was diagnosed with pituitary dwarfism during childhood and was treated at another hospital with growth hormone supplement from 5 to 14 years of age. This patient was referred to our department at 17 weeks’ gestation due to a change of residence. At 30 weeks’ gestation, she was hospitalized for assessment of hydronephrosis and polyuria (15–20 L/day). Analysis of a 24‐h urine sample showed creatinine clearance of 157 mL/min and urine osmolality of 38 mOsm/L. The patient's urine output decreased after receiving a test dose of 0.75 g of 1‐desamino‐8‐D‐arginine vasopressin (DDAVP). Cranial magnetic resonance imaging showed transection of the pituitary stalk. Subsequently, the patient's urine output was well controlled by a maintenance dose of 0.275 mL/day intranasal DDAVP. A cesarean section was performed at 37 weeks, as the patient height was 138 cm, and a pelvic X‐ray showed cephalopelvic disproportion. She delivered a female baby weighing 2302 g, and both 1‐ and 5‐min Apgar scores were 9. The patient was followed up after 4 months and showed no visual deterioration or polyuria while on DDAVP therapy, while the neonate grew favorably.
Axonal damage and demyelination in long‐term dorsal root ganglia cultures from a rat model of Charcot–Marie–Tooth type 1A disease
Authors: Nobbio Lucilla , Gherardi Gianfranco , Vigo Tiziana , Passalacqua Mario , Melloni Edon , Abbruzzese Michele , Mancardi Gianluigi , Nave Klaus‐Armin , Schenone Angelo 
Published: March 2006

AbstractClinical progression in hereditary and acquired demyelinating disorders of both the central and peripheral nervous system is mainly due to a time‐dependent axonal impairment. We established 90‐day dorsal root ganglia (DRG) cultures from a rat model of Charcot–Marie–Tooth type 1A (CMT1A) neuropathy to evaluate the structure of myelin and axons, and the expression of myelin‐related proteins and cytoskeletal components, by morphological and molecular techniques. Both wild‐type and CMT1A cultures were rich in myelinated fibres. Affected cultures showed dysmyelinated internodes and focal myelin swellings. Furthermore, uncompacted myelin and smaller axons with increased neurofilament (NF) density were found by electron microscopy, and Western blots showed higher levels of nonphosphorylated NF. Confocal microscopy demonstrated an abnormal distribution of the myelin‐associated glycoprotein which, instead of being expressed at the noncompact myelin level, showed focal accumulation along the internodes while other myelin proteins were normally distributed. These findings suggest that CMT1A DRG cultures, similarly to the animal model and human disease, undergo axonal atrophy over a period of time. This model may be utilized to study the molecular changes underlying demyelination and secondary axonal impairment. As axonal damage may occur after just 3 months and tissue cultures represent a strictly controlled environment, this model may be ideal for testing neuroprotective therapies.
Kv3 potassium channels control the duration of different arousal states by distinct stochastic and clock‐like mechanisms
Authors: Joho Rolf H. , Marks Gerald A. , Espinosa Felipe 
Published: March 2006

AbstractSleep–wake behavior is tightly controlled in many animal species, suggesting genetically encoded, homeostatic control mechanisms that determine arousal‐state dynamics. We reported that two voltage‐gated potassium channels, Kv3.1 and Kv3.3, control sleep in wild‐type and Kv3‐mutant mice. Compared with wild‐type (WT), homozygous double mutants (DKO) that lack these channels sleep 40% less in the light and 22% less in the dark. To understand how the lack of these channels affects sleep, we analysed arousal‐state changes during the light period where the differences are greatest between WT and DKO. We determined the kinetic complexity of each arousal state from the episode durations of wakefulness, slow‐wave sleep and rapid eye movement sleep (REMS). Based on the number of exponential components in episode‐duration histograms, WT and DKO mice have several kinetically distinct states of wakefulness, and these states are longer in duration in DKO. For slow‐wave sleep, WT mice have a single slow‐wave sleep (SWS) state in contrast to DKO mice, which show two distinct SWS states, one that is 60% shorter than that in WT and a second that is similar in duration. Both WT and DKO mice have two kinetically distinct REMS states. DKO mice show an 84% reduction in the frequency of short REMS episodes (< 45 s) without any change in the occurrence of long REMS episodes (> 60 s). In contrast to the stochastic control of episode durations of wakefulness and SWS, the durations of both REMS states are normally distributed, indicating that the underlying control processes are fundamentally different.
Estrogen‐dependent selectivity of genomic responses to birdsong
Authors: Maney Donna L. , Cho Ellen , Goode Christopher T. 
Published: March 2006

AbstractBehavioral responses to sociosexual signals often depend on gonadal steroid hormones, which are thought to modulate behavior by acting on motivational systems in the brain. There is mounting evidence that sex steroids may also modulate perception of sociosexual signals by affecting sensory processing. In seasonally breeding songbirds such as the white‐throated sparrow (Zonotrichia albicollis), the female's behavioral response to hearing male song depends on her plasma levels of estradiol (E2). Here, we examined whether plasma E2 also affects the selectivity of the song‐induced zenk (egr‐1) response in the auditory forebrain, which is known to vary according to the behavioral relevance of song stimuli. Non‐breeding females were held on a winter‐like photoperiod and implanted with silastic capsules containing either no hormone or E2. E2‐treated birds hearing 42 min of conspecific song had more cells immunoreactive for the protein product of zenk in the auditory forebrain than did those hearing frequency‐matched synthetic tones. In birds not treated with E2, however, the zenk response to song did not differ from that to tones. We found similar effects in the avian homolog of the inferior colliculus, indicating that E2 may affect the processing of auditory information upstream of the forebrain. Our data suggest that in females, zenk induction in the auditory system is selective for song only when plasma E2 exceeds non‐breeding levels. E2‐dependent plasticity of auditory pathways and processing centres may promote recognition of and attention to conspecific song during the breeding season.
Olfactory sensory neurons expressing class I odorant receptors converge their axons on an antero‐dorsal domain of the olfactory bulb in the mouse
Authors: Tsuboi Akio , Miyazaki Takaaki , Imai Takeshi , Sakano Hitoshi 
Published: March 2006

AbstractVertebrate odorant receptor (OR) genes are divided phylogenetically into two distinct classes: the fish‐like class I and the terrestrial‐specific class II. In the present study, we systematically analysed mouse class I OR genes (42 subfamilies) to elucidate the expression profiles in the olfactory epithelium (OE) and the projection sites of their olfactory sensory neurons (OSNs) in the olfactory bulb (OB). In situ hybridization (ISH) revealed that most class I OR genes (36 subfamilies) were expressed in the dorso‐medial zone (zone 1) of the OE. Furthermore, there appeared to be no significant differences in the distributions of OSNs expressing class I genes within zone 1. These results indicate that there is a clear boundary between zone 1 and non‐zone 1 areas in the OE. Some class I ORs are known to possess ligand specificity for aliphatic acids, aldehydes and alcohols. Our ISH analysis has revealed that OSNs expressing the class I ORs in zone 1 tend to converge their axons on a cluster of glomeruli in an antero‐dorsal domain that is assumed to be involved in responses to the aliphatic compounds on the OB.
Dopaminergic modulation of long‐lasting direct current‐induced cortical excitability changes in the human motor cortex
Authors: Nitsche Michael A. , Lampe Christian , Antal Andrea , Liebetanz David , Lang Nicolas , Tergau Frithjof , Paulus Walter 
Published: March 2006

AbstractDopaminergic mechanisms participate in N‐methyl‐d‐aspartate (NMDA) receptor‐dependent neuroplasticity, as animal experiments have shown. This may be similar in humans, where dopamine influences learning and memory. We tested the role of dopamine in human cortical neuroplasticity. Changes of excitability were induced by transcranial direct current stimulation (tDCS). D2 receptor blocking by sulpiride abolished the induction of after‐effects nearly completely. D1 activation alone in the presence of D2 receptor blocking induced by co‐administration of sulpiride and pergolide did not re‐establish the excitability changes induced by tDCS. This suggests that D2 receptors play a major supporting role in inducing neuroplasticity in the human motor cortex. Enhancement of D2 and, to a lesser degree, D1 receptors by pergolide consolidated tDCS‐generated excitability diminution until the morning after stimulation. The readiest explanation for this pattern of results is that D2 receptor activation has a consolidation‐enhancing effect on tDCS‐induced changes of excitability in the human cortex. The results of this study underscore the importance of the dopaminergic system for human neuroplasticity, suggest a first pharmacological add‐on mechanism to prolong the excitability‐diminishing effects of cathodal tDCS for up to 24 h after stimulation, and thus render the application of tDCS practicable in diseases displaying enhanced cortical excitability, e.g. migraine and epilepsy.
Force and time control in the production of rhythmic movement sequences in Parkinson's disease
Authors: Pope Paul A. , Praamstra Peter , Wing Alan M. 
Published: March 2006

AbstractThis study investigated force and time control in rhythm production in Parkinson's disease. Patients and age‐matched controls reproduced rhythms consisting of equal (600 ms) or alternating (400 and 800 ms) intervals, produced with equal (12 N) or alternating (8 and 16 N) forces, under paced (synchronization) and unpaced (continuation) conditions. Performance was assessed in terms of accuracy and variability. Reproduction of force amplitudes was less accurate in patients than in controls when either time or force alternated but did not deteriorate further when force and time alternated. In contrast, interval timing was least accurate in patients compared with controls when rhythm alternated on both dimensions. The ratio between alternating force levels was better maintained by controls than by patients, without influence of timing requirements in either group. In contrast, the ratio between alternating intervals was relatively preserved in patients when force remained constant but was severely compromised when force alternated. Timing variability was greater in the patient group, especially in the more affected side, but there was no difference in timing variability between groups as a function of rhythm, and there were no differences between groups in variability of force. The results show that force and time control in patients are affected in different ways. We interpret the preserved timing of rhythms with alternation on one dimension as evidence of intact ability to organize movements in a sequence. The data are compatible with a basal ganglia role in the coregulation of time and force, but do not support a general timing function of the basal ganglia.
CB2 receptor‐mediated antihyperalgesia: possible direct involvement of neural mechanisms
Authors: Beltramo M. , Bernardini N. , Bertorelli R. , Campanella M. , Nicolussi E. , Fredduzzi S. , Reggiani A. 
Published: March 2006

AbstractIn mouse the cannabinoid receptor 2 (CB2) agonists L768242 and (+)‐AM1241, at doses of 30 mg/kg i.p. and 1 and 3 mg/kg i.v., respectively, reduced the second phase of nocifensive behaviors elicited by formalin intraplantar injection. This effect was counteracted by the selective CB2 antagonist SR144528 (1 mg/kg i.p.). In rat (+)‐AM1241 (3 and 6 mg/kg i.v.) and L768242 (30 mg/kg i.p.) reduced allodynia elicited by L5–L6 spinal nerve ligation. SR144528 reverted these effects, supporting a CB2‐mediated action. To clarify the mechanisms underlying these effects we investigated CB2 gene expression and function in the nervous system. CB2 mRNA was expressed in spinal cord and dorsal root ganglia (DRG) of both sham and neuropathic rats and was up‐regulated in the ipsilateral spinal cord of neuropathic rats. Expression studies demonstrated the presence of CB2 mRNA in culture of spinal cord microglia. A biomarker, CGRP, was used to investigate modulation of DRG primary afferents by CB2 agonists. Both L768242 and (+)‐AM1241 dose dependently (EC50 of 3.6 and 4.5 nm, respectively) reduced capsaicin‐induced calcitonin gene‐related peptide (CGRP) release. Coadministration of SR144528 resulted in a rightforward shift (pKB 8.1 and 8.2 for (+)‐AM1241 and L768242, respectively) of the dose–response curve. Experiments on capsaicin‐induced CGRP release in tissue from CB1–/– mice ruled out a CB1‐mediated effect. These results confirm that CB2 is present in the central nervous system and suggest that CB2 agonists may elicit their analgesic effect by acting not only at non‐neuronal peripheral sites but also at neural level, making CB2 an attractive target for chronic pain treatment.
Identification of genes co‐upregulated with Arc during BDNF‐induced long‐term potentiation in adult rat dentate gyrus in vivo
Authors: Wibrand Karin , Messaoudi Elhoucine , Håvik Bjarte , Steenslid Vibeke , Løvlie Roger , Steen Vidar M. , Bramham Clive R. 
Published: March 2006

AbstractBrain‐derived neurotrophic factor (BDNF) is a critical regulator of transcription‐dependent adaptive neuronal responses, such as long‐term potentiation (LTP). Brief infusion of BDNF into the dentate gyrus of adult anesthetized rats triggers stable LTP at medial perforant path‐granule synapses that is transcription‐dependent and requires induction of the immediate early gene Arc. Rather than acting alone, Arc is likely to be part of a larger BDNF‐induced transcriptional program. Here, we used cDNA microarray expression profiling to search for genes co‐upregulated with Arc 3 h after BDNF‐LTP induction. Of nine cDNAs encoding for known genes and up‐regulated more than four‐fold, we selected five genes, Narp, neuritin, ADP‐ribosylation factor‐like protein‐4 (ARL4L), TGF‐β‐induced immediate early gene‐1 (TIEG1) and CARP, for further validation. Real‐time PCR confirmed robust up‐regulation of these genes in an independent set of BDNF‐LTP experiments, whereas infusion of the control protein cytochrome C had no effect. In situ hybridization histochemistry further revealed up‐regulation of all five genes in somata of post‐synaptic granule cells following both BDNF‐LTP and high‐frequency stimulation‐induced LTP. While Arc synthesis is critical for local actin polymerization and stable LTP formation, several of the co‐upregulated genes have known functions in excitatory synaptogenesis, axon guidance and glutamate receptor clustering. These results provide novel insight into gene expression responses underlying BDNF‐induced synaptic consolidation in the adult brain in vivo.
Effect of auditory cortex lesions on the discrimination of frequency‐modulated tones in rats
Authors: Rybalko Natalia , Šuta Daniel , Nwabueze‐Ogbo Fidel , Syka Josef 
Published: March 2006

AbstractThe lateralization of functions to individual hemispheres of the mammalian brain remains, with the exception of the human brain, unresolved. The aim of this work was to investigate the ability to discriminate between falling and rising frequency‐modulated (FM) stimuli in rats with unilateral or bilateral lesions of the auditory cortex (AC). Using an avoidance conditioning procedure, thirsty rats were trained to drink in the presence of a rising FM tone and to stop drinking when a falling FM tone was presented. Rats with a lesion of the AC were able to learn to discriminate between rising and falling FM tones; however, they performed significantly worse than did control rats. A greater deficit in the ability to discriminate the direction of frequency modulation was observed in rats with a right or bilateral AC lesion. The discrimination performance (DP) in these rats was significantly worse than the DP in rats with a left AC lesion. Animals with a right or bilateral AC lesion improved their DP mainly by recognizing the pitch at the beginning of the stimuli. The lesioning of the AC in trained animals caused a significant decrease in DP, down to chance levels. Retraining resulted in a significant increase in DP in rats with a left AC lesion; animals with a right lesion improved only slightly. The results demonstrate a hemispheric asymmetry of the rat AC in the recognition of FM stimuli and indicate the dominance of the right AC in the discrimination of the direction of frequency modulation.
Patterns in body mass distributions: sifting among alternative hypotheses
Authors: Allen C. R. , Garmestani A. S. , Havlicek T. D. , Marquet P. A. , Peterson G. D. , Restrepo C. , Stow C. A. , Weeks B. E. 
Published: March 2006

AbstractUnderstanding how animals interact with their environment is critical for evaluating, mitigating and coping with anthropogenic alteration of Earth's biosphere. Researchers have attempted to understand some aspects of these interactions by examining patterns in animal body mass distributions. Energetic, phylogenetic, biogeographical, textural discontinuity and community interaction hypotheses have been advanced to explain observed patterns. Energetic and textural discontinuity hypotheses focus upon the allometry of resource use. The community interaction hypothesis contends that biotic interactions within assemblages of species are of primary importance. Biogeographical and phylogenetic hypotheses focus on the role of constraints on the organization of communities. This paper examines and organizes these various propositions about species body mass distributions and discusses the multiple competing hypotheses, how their predictions vary, and possible methods by which the hypotheses can be distinguished and tested. Each of the hypotheses is partial, and explains some elements of pattern in body mass distributions. The scale of appropriate application, relevance and interpretation varies among the hypotheses, and the mechanisms underlying observed patterns are likely to be multicausal and vary with scale.
Expression profiles of fhs (FTHFS) genes support the hypothesis that spirochaetes dominate reductive acetogenesis in the hindgut of lower termites
Authors: Pester Michael , Brune Andreas 
Published: March 2006

SummaryReductive acetogenesis is an important metabolic process in the hindgut of wood‐feeding termites. We analysed diversity and expression profiles of the bacterial fhs gene, a marker gene encoding a key enzyme of reductive acetogenesis, formyl tetrahydrofolate synthetase (FTHFS), to identify the active homoacetogenic populations in representatives of three different termite families. Clone libraries of polymerase chain reaction‐amplified fhs genes from hindgut contents of Reticulitermes santonensis (Rhinotermitidae) and Cryptotermes secundus (Kalotermitidae) were compared with previously published fhs gene sequences obtained from Zootermopsis nevadensis (Termopsidae). Most of the clones clustered among the ‘Termite Treponemes’, which comprise also the fhs genes of the two strains of the homoacetogenic spirochaete Treponema primitia. The high abundance of treponemal fhs genes in all clone libraries was in agreement with the results of DNA‐based terminal‐restriction fragment length polymorphism (T‐RFLP) analysis. Moreover, in mRNA‐based T‐RFLP profiles of the three termites, only expression of fhs genes of ‘Termite Treponemes’ was detected, albeit at different levels. In C. secundus, only one of the dominating phylotypes was transcribed, while in R. santonensis, the apparently less abundant fhs genes were the most actively expressed. Our results strongly support the hypothesis that spirochaetes are responsible for reductive acetogenesis in the hindgut of lower, wood‐feeding termites.
A paradox explained? Patients with delayed diagnosis of symptomatic colorectal cancer have good prognosis
Authors: Rupassara K. S. , Ponnusamy S. , Withanage N. , Milewski P. J. 
Published: March 2006

AbstractObjective  To investigate the impact on outcome of delay between referral and diagnosis in colorectal cancer (CRC).Patients and methods  One hundred and fifty‐four patients were studied after excluding from a consecutive series of 411 with CRC, those with factors known to affect the prognosis that may also have affected the speed of diagnosis. These were advanced disease, emergency admission or surgery, referral with diagnosis already made, and tumours treated by colonoscopic polypectomy alone. Possible causative factors were compared between early and late diagnosis groups. For assessment of symptom risk, the Department of Health criteria were used.Results  Forty‐four patients had Referral to Diagnosis Interval (RDI) ≥ 50 days (‘Late’), and 110 had RDI < 50 days (‘Early’). In the Late group there were only 2 deaths from cancer and 93.7% cancer‐specific five year survival (c5ys), compared with 22 and 65.3%, respectively, in the Early one (P = 0.007). There were more Duke's A cases in the Late group (38.6%vs 15.2%, P = 0.006), but this did not fully explain the improved survival. Comparisons for each Duke's Stage showed improved c5ys for Late Duke's B ones (100% of 16 vs 60.3% of 54, P = 0.039). Late patients had more low risk symptoms than Early ones, both overall (31.8%vs 13.7%, P = 0.013) and in Duke's B cases (56%vs 15.3%, P = 0.003). Tumours were smaller in the Late group (length 35.3 vs 41.6 mm, P= 0.04); this difference was confined to the Duke's A patients and sigmoid tumours. Late sigmoid tumours were not only shorter (32.4 vs 45.9 mm, P = 0.02) but also were all cured (c5ys 100% of 18 vs 60.3% of 23, P = 0.011). There were no differences between Late and Early groups in: age (mean 69.9 years), sex (male 57.7%), date of diagnosis (mean December 1998), ASA comorbidity index (mean 1.9), number of lymph nodes found in the operative specimen (mean 8.6), or histological grading (moderate differentiation 94.4%).Conclusion  In the context of modern rapid access clinics, symptomatic CRC patients with delay between referral and diagnosis (even if this is several months or occasionally more than a year) have less aggressive tumours and markedly better long‐term cure rate than their earlier diagnosed counterparts. Attempts to speed up further the diagnosis would be a waste of time and resources, being unlikely to make an appreciable difference to the overall cure rate.