bluuebunny/crossref_metadata_2025_split huggingface dataset:
Combined radioguided occult lesion and sentinel node localization for breast cancer
Authors: Kim Joon , Chung David , Spillane Andrew 
Published: July 2004

Introduction:  The incidence of non‐palpable breast lesions requiring intraoperative localization has greatly increased, particularly because of the widespread use of mammographic screening. These lesions have previously been localized preoperatively using hook‐wire or carbon track techniques. In the era of increasing acceptance of sentinel node biopsy (SNB) a separate procedure would be required for sentinel node localization (SNL). The present study describes an experience with ultrasound guided radionucleotide occult lesion localization (ROLL) as a reliable alternative that enables SNL synchronously.Methods:  Twenty‐two patients with proven breast malignancy on core biopsy were enrolled in the present study. Preoperatively, technetium‐99m was injected around the lesion under radiological guidance. A γ‐probe was then used to locate the lesion and guide its surgical removal. Complete excision was then confirmed immediately by verifying minimal residual radioactivity in the cavity wall tissue. Appropriate SNB then proceeded.Results:  The primary breast lesion was identified in all cases except in one, where the radiotracer was injected into the wrong site, giving a miss rate of 1/22 (4.5%). The average size of the tumour was 13 mm (range 6−22 mm) and the closest margins ranged from 0 (1 patient) to 22 mm (mean 7 mm). Two patients had inadequate margins and required further excision giving a re‐excision rate of 2/21 (9.5%). SNB specimens included a median of 3.7 nodes/patientConclusion:  Radionucleotide occult lesion localization/SNL is a simple, accurate and reliable method of combining localization of impalpable breast lesions with the localization required for SNB. The miss and re‐excision rates compare favourably with the needle‐wire systems and carbon tracking techniques. There are significant resource efficiency and time advantages.
Is procalcitonin a reliable marker for the diagnosis of infected pancreatic necrosis?
Authors: Yonetci Nadir , Sungurtekin Ugur , Oruc Nevin , Yilmaz Mustafa , Sungurtekin Hulya , Kaleli Ilknur , Kaptanoglu Bunyamin , Yuce Gul , Ozutemiz Omer 
Published: July 2004

Background:  Infected necrosis in acute pancreatitis is the main factor in determining the prognosis of the disease. Early and accurate diagnosis of infected pancreatic necrosis might decrease mortality. The aim of the present study is to identify a reliable marker for the onset infection in three different experimentally induced pancreatitis models.Methods:  Ninety female Wistar albino rats were randomly divided into nine groups. In three different experimental models, including cerulein induced acute oedematous pancreatitis (AEP), sterile pancreatic necrosis due to taurocholate‐induced acute pancreatitis (SPN) and infected pancreatic necrosis taurocholate‐induced acute pancreatitis (IPN). Serum levels of procalcitonin (PCT), C‐reactive protein (CRP), tumour necrosis factor a (TNF‐α), interleukin 6 (IL‐6) and interleukin 8 (IL‐8), amylase were measured. The degree of pancreatic damage also evaluated pathologically.Results:  Procalcitonin levels were increased significantly in AEP, SPN and IPN compared to control groups (P < 0.05). PCT and IL‐6 level were the highest in the IPN group (P < 0.05). Serum amylase, CRP, TNF‐α, IL‐2, and IL‐8 levels were similar between IPN and SPN groups (P > 0.05), but higher than in other groups. The results of histological evaluation also correlated with the advent of the disease.Conclusion:  Procalcitonin and IL‐6 acts as reliable acute phase reactant in an experimental model of AEP, SPN and IPN in the rat. PCT and IL‐6 combination might be surrogate marker of infected pancreatic necrosis and should be preferred to other markers assay especially in severe pancreatitis.
Anaplastic thyroid carcinoma: dismal outcome despite current treatment approach
Authors: Veness Michael J. , Porter Guy S. , Morgan Gary J. 
Published: July 2004

Background:  Anaplastic thyroid carcinoma (ATC) accounts for <5% of all thyroid malignancies and is one of the most aggressive malignancies known. Survival is limited to months and death is often caused by uncontrolled neck disease. There is evidence that multimodality treatment, incorporating surgery (Sx), external beam radiotherapy (RT) and chemotherapy (CT), might enhance local control and improve survival.Methods:  Between 1979 and 2002, 18 patients with ATC were referred to the multidisciplinary Head and Neck Cancer Service, Westmead Hospital, Sydney, Australia. The aim of the present study is to report on the treatment and outcome of these patients. Survival was calculated from the time of diagnosis until death using the Kaplan−Meier method.Results:  Median age at diagnosis was 72 years (29−92 years) in 12 women and six men. Five patients had distant metastases at diagnosis. Seven patients were treated with various combinations of Sx, RT and/or CT. Ten patients received a single modality, including three undergoing a total thyroidectomy. Many patients died from local disease progression. Only one patient received triple modality treatment (Sx/RT/CT), surviving 26 months, and maintaining local control until death. Sixteen patients died from disease with a median survival of 6.2 months (0.3−56.8 months).Conclusion:  Most patients with ATC are incurable; however, a multimodality approach incorporating Sx and RT ± CT, in selected individuals, might improve local control and extend survival.
Epidemiological changes in colorectal cancer in Shiraz, Iran: 1980−2000
Authors: Hosseini Seyed Vahid , Izadpanah Ahmad , Yarmohammadi Hooman 
Published: July 2004

Background:  The present study was performed to determine trends in colorectal cancer rates over the past two decades (1970−80 vs 1990−2000) with in a main referral centre in Shiraz, Iran.Methods:  The Cancer Registry data on all colorectal cancer cases from 1970 to 2000 in Shiraz, Iran, were analysed. Demographic characteristics, clinical features, cancer site and type and stage of cancer were compared in the populations of two different decades.Results:  The age‐adjusted incidence of colorectal cancer per 100 000 population per year increased in men from a mean annual incidence of 1.61 in the decade 1970−80 to 4.2 in 1990−2000 (P < 0.05), and in women from 2.35 to 2.72 (P < 0.05). In 1970−80, patients over 60 years had 62.5% of all the colorectal cancers, which decreased to 30% in 1990−2000 (P < 0.05). The distribution of right and left sided cancers were almost equal and showed no significant difference between the two decades (P > 0.05).Conclusion:  A marked increase in the incidence of colorectal cancer has been shown in Shiraz. Also, the marked increase in the incidence of colorectal cancer in the 40−60‐year‐old age group shown in the present study necessitates a more detailed work‐up in younger age group patients.
Quadratic damage rule in random loading case
Authors: KOŠÚT J. 
Published: July 2004

ABSTRACTThe simple mathematical structure of the quadratic damage rule (QDR) enables mathematical expression of the failure condition in the case of random loading. Random loading after modified rainflow analysis is considered as a random marked point process. Moments of the damage distribution can be expressed by use of ensemble averages. A condition for validity of the first damage moment solution is formulated. The QDR damage first moment solution involves failure predictions for both stationary and non‐stationary loadings. In these cases, final fracture conditions suitable for practical use are derived. QDR predicts fatigue lives that are always shorter than the linear damage rule (LDR) in the case of stationary loading with short interval of statistical dependence of random variables. QDR appears to be a suitable additional engineering tool for random loading fatigue life predictions considering loading sequence and loading level interactions.
Weight functions and stress intensity factors for quarter‐elliptical corner cracks in fastener holes
Authors: CHEN Q. , WANG X. 
Published: July 2004

ABSTRACTApproximate weight functions for a quarter‐elliptical crack in a fastener hole were derived from a general weight function form and two reference stress intensity factors. Closed‐form expressions were obtained for the coefficients of the weight functions. The derived weight functions were validated against numerical data by comparison of stress intensity factors calculated for several nonlinear stress fields. Good agreements were achieved. These derived weight functions are valid for the geometric range of 0.5 ≤a/c≤ 1.5 and 0 ≤a/t≤ 0.8 and R/t= 0.5; and are given in forms suitable for computer numerical integration. The weight functions appear to be particularly suitable for fatigue crack growth prediction of corner cracks in fastener holes and fracture analysis of such cracks in complex stress fields.
Somatodendritic minicolumns of output neurons in the rat visual cortex
Authors: Vercelli Alessandro E. , Garbossa Diego , Curtetti Roberta , Innocenti Giorgio M. 
Published: July 2004

AbstractThe apical dendrites of the pyramidal neurons of the cerebral cortex form radial bundles in all species and areas. Using microtubule‐associated protein (MAP)2 immunostaining and Voronoi tessellation analysis in the rat visual cortex, we obtained objective criteria to define dendritic bundles in tangential sections: in supragranular layers of the rat visual cortex we found bundles of 6–6.4 dendrites, at a density of 1929 bundles/mm2 and a centre‐to‐centre distance of 27 µm. Using lipophilic tracers to label different pyramidal cell populations, based on the same criteria as in MAP2‐immunostained material, we found that in the rat visual cortex the bundles consist of neurons with specific targets. Neurons projecting to the ipsi‐ or contralateral cortex form bundles together and with neurons projecting to the striatum, but not with those projecting to the superior colliculus, dorsal division of the lateral geniculate nucleus or through the cerebral peduncle. The latter neurons form bundles with neurons projecting to the striatum. Thus, the cerebral cortex is organized in minicolumns of output neurons visible at the earliest ages studied (P3), which might have a higher probability of being interconnected than those outside.
Disruption of hippocampal CA3 network: effects on episodic‐like memory processing in C57BL/6J mice
Authors: Daumas Stéphanie , Halley Hélène , Lassalle Jean‐Michel 
Published: July 2004

AbstractLesion studies have demonstrated the prominent role of the hippocampus in spatial and contextual learning. To better understand how contextual information is processed in the CA3 region during learning, we focused on the CA3 autoassociative network hypothesis. We took advantage of a particularity of the mossy fibre (MF) synapses, i.e. their high zinc concentration, to reversibly disrupt the afferent MF pathway by microinfusions of an intracellular (DEDTC) or an extracellular (CaEDTA) zinc chelator into the CA3 area of the dorsal hippocampus of mice. Disruption of the CA3 network significantly impaired the acquisition and the consolidation of contextual fear conditioning, whereas contextual retrieval was unaffected. These results also suggest a heterogeneity between the cognitive processes underlying spatial and contextual memory that might be linked to the specific involvement of free zinc in contextual information processing.
Quantitative effects produced by modifications of neuronal activity on the size of GABAA receptor clusters in hippocampal slice cultures
Authors: Marty Serge , Wehrlé Rosine , Fritschy Jean‐Marc , Sotelo Constantino 
Published: July 2004

AbstractThe number and strength of GABAergic synapses needs to be precisely adjusted for adequate control of excitatory activity. We investigated to what extent the size of GABAA receptor clusters at inhibitory synapses is under the regulation of neuronal activity. Slices from P7 rat hippocampus were cultured for 13 days in the presence of bicuculline or 4‐aminopyridine (4‐AP) to increase neuronal activity, or DNQX to decrease activity. The changes provoked by these treatments on clusters immunoreactive for the α1 and α2 subunits of the GABAA receptor or gephyrin were quantitatively evaluated. While an increase in activity augmented the density of these clusters, a decrease in activity provoked, in contrast, a decrease in their density. An inverse regulation was observed for the size of individual clusters. Bicuculline and 4‐AP decreased whilst DNQX increased the mean size of the clusters. When the pharmacological treatments were applied for 2 days instead of 2 weeks, no effects on the size of the clusters were observed. The variations in the mean size of individual clusters were mainly due to changes in the number of small clusters. Finally, a regulation of the size of GABAA receptor clusters occurred during development in vivo, with a decrease of the mean size of the clusters between P7 and P21. This physiological change was also the result of an increase in the number of small clusters. These results indicate that neuronal activity regulates the mean size of GABAA receptor‐ and gephyrin‐immunoreactive clusters by modifying specifically the number of synapses with small clusters of receptors.
Cell‐type‐specific splicing of KChIP4 mRNA correlates with slower kinetics of A‐type current
Authors: Baranauskas Gytis 
Published: July 2004

AbstractIn neurons, rapidly inactivating A‐type potassium currents regulate repetitive firing and sensitivity to synaptic inputs both in the soma and in the dendrites. It has been established that Kv4 family subunits with several modifying proteins such as KChIPs are responsible for A‐type current in most neurons. However, it is not clear which of these modifying proteins are responsible for the observed difference in the properties of A‐type currents in the neurons. For example, in globus pallidus (GP) and basal forebrain (BF) neurons in rats, A‐type current possesses a slowly inactivating (τ > 80 ms) component of inactivation that is absent in the currents obtained from striatal cholinergic interneurons (StrI) and hippocampal area CA1 pyramidal neurons (HIP). It has been shown that KChIP4 splice variant A but not splice variant B can increase inactivation rates of Kv4 current to > 100 ms in Xenopus oocytes. We tested the hypothesis that cell‐specific expression of KChIP4A is responsible for the slow inactivation of A‐type current in these neurons. Employing single‐cell RT‐PCR in acutely dissociated rat neurons, KChIP4A mRNA was detected in 12/14 GP cells and in 12/14 BF neurons whereas it was not detected in any StrI or HIP cells. By contrast, the KChIP4 splice variant B was detected in all four types of cells. Moreover, deactivation rates at −100 mV were slower in BF and GP cells than in StrI and HIP neurons as expected, owing to the presence KChIP4A in BF and GP neurons. These data are consistent with our initial hypothesis.
Induced visual illusions and gamma oscillations in human primary visual cortex
Authors: Adjamian Peyman , Holliday Ian E. , Barnes Gareth R. , Hillebrand Arjan , Hadjipapas Avgis , Singh Krish D. 
Published: July 2004

AbstractUsing magnetoencephalography, we studied the spatiotemporal properties of cortical responses in terms of event‐related synchronization and event‐related desynchronization to a range of stripe patterns in subjects with no neurological disorders. These stripes are known for their tendency to induce a range of abnormal sensations, such as illusions, nausea, dizziness, headache and attacks of pattern‐sensitive epilepsy. The optimal stimulus must have specific physical properties, and maximum abnormalities occur at specific spatial frequency and contrast. Despite individual differences in the severity of discomfort experienced, psychophysical studies have shown that most observers experience some degree of visual anomaly on viewing such patterns. In a separate experiment, subjects reported the incidence of illusions and discomfort to each pattern. We found maximal cortical power in the gamma range (30–60 Hz) confined to the region of the primary visual cortex in response to patterns of 2–4 cycles per degree, peaking at 3 cycles per degree. This coincides with the peak of mean illusions and discomfort, also maximal for patterns of 2–4 cycles per degree. We show that gamma band activity in V1 is a narrow band function of spatial frequency. We hypothesize that the intrinsic properties of gamma oscillations may underlie visual discomfort and play a role in the onset of seizures.
A novel role for polyamines in adult neurogenesis in rodent brain
Authors: Malaterre Jordane , Strambi Colette , Aouane Aïcha , Strambi Alain , Rougon Geneviève , Cayre Myriam 
Published: July 2004

AbstractAlthough neurogenesis in the adult is known to be regulated by various internal cues such as hormones, growth factors and cell‐adherence molecules, downstream elements underlying their action at the cellular level still remain unclear. We previously showed in an insect model that polyamines (putrescine, spermidine and spermine) play specific roles in adult brain neurogenesis. Here, we demonstrate their involvement in the regulation of secondary neurogenesis in the rodent brain. Using neurosphere assays, we show that putrescine addition stimulates neural progenitor proliferation. Furthermore, in vivo depletion of putrescine by specific and irreversible inhibition of ornithine decarboxylase, the first key enzyme of the polyamine synthesis pathway, induces a consistent decrease in neural progenitor cell proliferation in the two neurogenic areas, the dentate gyrus and the subventricular zone. The present study reveals common mechanisms underlying birth of new neurons in vertebrate and invertebrate species.
Influence of the hippocampus on interneurons of the rat prefrontal cortex
Authors: Tierney Patrick L. , Dégenètais Eric , Thierry Anne‐Marie , Glowinski Jacques , Gioanni Yves 
Published: July 2004

AbstractThe hippocampus and prefrontal cortex (PFC), two structures implicated in learning and memory processes, are linked by a direct hippocampo‐prefrontal pathway. It has been shown that PFC pyramidal cells receive monosynaptic excitatory inputs from the hippocampus and, in this study, we sought to determine the influence of the hippocampus on PFC interneurons in anesthetized rats. Extracellular recordings were coupled to juxtacellular injections of neurobiotin or biotinylated dextran amine to morphologically differentiate interneurons from pyramidal cells. In all cases, the action potentials of labeled interneurons were of shorter duration (< 0.70 ms) than those of identified pyramidal cells (> 0.70 ms). Single pulse stimulation of the hippocampal CA1/subiculum region induced an excitatory response in 70% of recorded interneurons in the prelimbic and medial‐orbital areas of the PFC. In contrast to the one to two action potentials generated by pyramidal cells, an important group of interneurons fired a burst of action potentials in response to hippocampal stimulation. A large proportion of these excitatory responses was probably monosynaptic as their latency is consistent with the conduction time of the hippocampo‐prefrontal pathway. In addition, when both a pyramidal cell and an interneuron were simultaneously recorded and both responded to stimulation, the interneuron consistently fired before the pyramidal cell. In conclusion, the hippocampus exerts a direct excitatory influence on PFC interneurons and is thus capable of feedforward inhibition of pyramidal cells. Hippocampal output is spatially and temporally focalized via this inhibitory process and consequently could facilitate the synchronization of a specific subset of PFC neurons with hippocampal activity.
Peripheral noxious stimulation induces phosphorylation of the NMDA receptor NR1 subunit at the PKC‐dependent site, serine‐896, in spinal cord dorsal horn neurons
Authors: Brenner Gary J. , Ji Ru‐Rong , Shaffer Sebastian , Woolf Clifford J. 
Published: July 2004

AbstractThe N‐methyl‐D‐aspartate receptor (NMDAR) contributes to central sensitization in the spinal cord and the generation of pain hypersensitivity. NMDAR function is modulated by post‐translational modifications including phosphorylation, and this is proposed to underlie its involvement in the production of pain hypersensitivity in the spinal cord. We now show that a noxious heat stimulus applied to the rat hindpaw induces phosphorylation of the NMDAR NR1 subunit at a protein kinase C (PKC)‐dependent site, serine‐896, in superficial dorsal horn neurons. Phosphorylation of NR1 serine‐896 is essentially absent in the superficial dorsal horn laminae of naïve rats, but there is rapid (< 2 min) induction following a noxious but not innocuous heat stimulus. The number of pNR1‐immunoreactive neuronal profiles in the superficial dorsal horn peaks 30 min after noxious heat stimulation and persists for up to 1 h. pNR1serine896 induction occurs in the endoplasmic reticulum, suggesting that it contributes to trafficking of the receptor from intracellular stores to the membrane. The phosphorylation of the subunit is attenuated by intrathecal injection of the NMDAR antagonist, MK801, suggesting that the NMDAR is involved via a feed‐forward mechanism in its own phosphorylation. The pNR1serine896‐positive neurons are highly co‐localized with PKCdelta and only rarely with PKCgamma. These data provide evidence for an activity‐dependent NMDAR phosphorylation at the PKC‐dependent site, serine‐896, in spinal cord dorsal horn neurons initiated by peripheral noxious stimuli.
The spatial and temporal pattern of fatty acid amide hydrolase expression in rat hippocampus during postnatal development
Authors: Morozov Yury M. , Ben‐Ari Yezekiel , Freund Tamas F. 
Published: July 2004

AbstractGABAergic synaptic transmission is efficiently controlled by endogenous cannabinoids in cortical structures. Fatty acid amide hydrolase (FAAH) is one of the metabolizing enzymes of endocannabinoids in the brain. In this study we investigated the cellular and subcellular distribution of FAAH at various timepoints during the first postnatal weeks, when GABA is still depolarizing, and plays a crucial role in network events. FAAH immunoreactivity is strong in the CA3 region already at postnatal day 0 (P0), but in CA1 only after P8. During this period, FAAH levels in hilar mossy cells decrease and in granule cells slowly increase. Pyramidal cells express FAAH first in the soma and proximal dendrites, and gradually in more distal segments, reaching adult levels in the most distal dendrites only at P22. Transient expression of FAAH was found in a small number of stratum radiatum cells that may be interneurons and in ependymal cells at the border of the alveus and corpus callosum between P2 and P8. At the ultrastructural level, FAAH distribution at all ages was very similar to the adult pattern, i.e. it was largely associated with the membrane of cytoplasmic vesicles, mitochondria and endoplasmic reticulum. During postnatal development of the hippocampus, the spatio‐temporal expression of FAAH correlates well with the general pattern of neuronal maturation, but not with the arrival of afferent pathways, which suggests that FAAH – and its major endocannabinoid substrate, anandamide – is unlikely to be involved in the presynaptic control of neurotransmission. Instead, FAAH may subserve general roles as the inactivating enzyme for many fatty acid amides, in addition to anandamide.