bluuebunny/crossref_metadata_2025_split huggingface dataset:
Astrocyte differentiation selectively upregulates CCL2/monocyte chemoattractant protein‐1 in cultured human brain‐derived progenitor cells
Authors: Lawrence Diane M.P. , Seth Pankaj , Durham Linda , Diaz Frank , Boursiquot Roosevelt , Ransohoff Richard M. , Major Eugene O. 
Published: October 2005

AbstractChemokines (chemoattractant cytokines) and their receptors are present in the brain and may play roles in both neurodevelopment and neuropathology. Increased brain levels of monocyte chemoattractant protein‐1 (MCP‐1), also known as CCL2, are found in patients with human immunodeficiency virus type 1 (HIV‐1)‐associated dementia and other acute and chronic neurologic diseases. Although the function of CCL2 in the brain is unclear, it is believed that upregulation of this chemokine during neuropathologic or neuroinflammatory conditions leads to recruitment of activated monocytes into the brain, where they differentiate into macrophages producing neurotoxic and inflammatory molecules. We recently showed that human fetal brain‐derived progenitor cells are susceptible to HIV‐1 and JC virus infection, and that differentiation toward an astrocyte phenotype increased virus production from these cells. In the current study, we found that in the absence of infection, progenitors produced moderate levels of CCL2 (5.6 ng per million cells). Astrocyte differentiation over 3 weeks increased CCL2 protein levels 30‐fold in a biphasic manner, whereas neuronal differentiation decreased production 20‐fold. Electromobility shift assays (EMSAs) demonstrated increased nuclear NF‐κB levels within 2 h of initiating astrocyte differentiation, and inhibitors of NF‐κB activation partially blocked the CCL2 increase in differentiating astrocytes. Transfection of progenitors with mutated CCL2 promoter/CAT reporter constructs showed that the distal promoter region, containing NF‐κB and NF‐I binding sites, is important for differentiation‐induced CCL2 upregulation. Together these results suggest that the transcription factor NF‐κB, and possibly NF‐I, contribute to the upregulation of CCL2 chemokine production during the differentiation of human progenitor cells toward an astrocyte phenotype. © 2005 Wiley‐Liss, Inc.
HIV‐1 Tat and opiate‐induced changes in astrocytes promote chemotaxis of microglia through the expression of MCP‐1 and alternative chemokines
Authors: El‐Hage Nazira , Wu Guanghan , Wang Juan , Ambati Jayakrishna , Knapp Pamela E. , Reed Janelle L. , Bruce‐Keller Annadora J. , Hauser Kurt F. 
Published: October 2005

AbstractOpiates exacerbate human immunodeficiency virus type 1 (HIV‐1) Tat1‐72‐induced release of key proinflammatory cytokines by astrocytes, which may accelerate HIV neuropathogenesis in opiate abusers. The release of monocyte chemoattractant protein‐1 (MCP‐1, also known as CCL2), in particular, is potentiated by opiate–HIV Tat interactions in vitro. Although MCP‐1 draws monocytes/macrophages to sites of CNS infection, and activated monocytes/microglia release factors that can damage bystander neurons, the role of MCP‐1 in neuro‐acquired immunodeficiency syndrome (neuroAIDS) progression in opiate abusers, or nonabusers, is uncertain. Using a chemotaxis assay, N9 microglial cell migration was found to be significantly greater in conditioned medium from mouse striatal astrocytes exposed to morphine and/or Tat1‐72than in vehicle‐, μ‐opioid receptor (MOR) antagonist‐, or inactive, mutant TatΔ31‐61‐treated controls. Conditioned medium from astrocytes treated with morphine and Tat caused the greatest increase in motility. The response was attenuated using conditioned medium immunoneutralized with MCP‐1 antibodies, or medium from MCP‐1−/−astrocytes. In the presence of morphine (time‐release, subcutaneous implant), intrastriatal Tat increased the proportion of neural cells that were astroglia and F4/80+macrophages at 7 days post‐injection. This was not seen after treatment with Tat alone, or with morphine plus inactive TatΔ31‐61or naltrexone. Glia displayed increased MOR and MCP‐1 immunoreactivity after morphine and/or Tat exposure. The findings indicate that MCP‐1 underlies most of the response of microglia, suggesting that one way in which opiates exacerbate neuroAIDS is by increasing astroglial‐derived proinflammatory chemokines at focal sites of CNS infection and promoting macrophage entry and local microglial activation. Importantly, increased glial expression of MOR can trigger an opiate‐driven amplification/positive feedback of MCP‐1 production and inflammation. © 2005 Wiley‐Liss, Inc.
Divergent effects of oncostatin M on astroglioma cells: Influence on cell proliferation, invasion, and expression of matrix metalloproteinases
Authors: Chen Shao‐Hua , Gillespie G. Yancey , Benveniste Etty N. 
Published: October 2005

AbstractOncostatin M (OSM), a cytokine of the interleukin‐6 (IL‐6) family, can either promote or inhibit cell growth in various normal and tumor cells. We addressed the effects of exogenous OSM on the proliferation and invasion of human astroglioma cells. In addition, we investigated one of the possible mechanisms involved: modulation of matrix metalloproteinase (MMP) expression and enzymatic activity. We found that OSM inhibited the proliferation of two human astroglioma cell lines (CH235‐MG and U87‐MG), and that this effect was not due to apoptosis. The inhibitory effect of OSM on proliferation was mediated through the gp130/OSMRβ receptor complex. To extend these findings, we analyzed the effects of OSM on primary tumor cells from glioblastoma patients. OSM suppressed the proliferation of primary glioblastoma cells, but not that of normal astrocytes. Interestingly, OSM did not suppress astroglioma cell invasion. This may be due to the differential regulation of MMPs by OSM. We found that OSM inhibited the constitutive expression of MMP‐2, while MMP‐9 expression was enhanced in astroglioma cell lines. We conclude that OSM inhibits proliferation of human astroglioma cells and primary glioblastoma cells via the gp130/OSMRβ receptor complex. However, OSM does not affect the invasive capacity of the astroglioma cells, which may be due to the divergent effects of OSM on MMP‐2 and MMP‐9 expression. Collectively, these findings suggest a complex role for OSM in astroglioma biology. © 2005 Wiley‐Liss, Inc.
Optimisation of microwave digestion for determination of Fe, Zn, Mn and Cu in various legumes by flame atomic absorption spectrometry
Authors: Erdoğan Selim , Erdemoğlu Sema B , Kaya Satılmış 
Published: October 2005

AbstractFe, Zn, Mn and Cu levels in three Turkish legumes, kidney bean (Phaseolus vulgaris L.), lentil (Lens esculenta) and chickpea (Cicer arietinum), were determined by flame atomic absorption spectrometry. Dissolution conditions in the microwave‐assisted wet digestion method were studied by investigating several variables, including type of acid mixture, acid volume, digestion time, microwave power input and sample weight. Comparison with conventional wet acid digestion was also made. In order to check the element losses during digestion and the accuracy of the results, all tests were repeated after the addition of a spiked standard element solution to the legume sample. The microwave‐assisted digestion procedure optimised for kidney bean was adapted for lentil and chickpea. Fe, Zn, Mn and Cu concentrations (mg per 100 g sample) were determined in kidney bean as 6.27 ± 0.94, 2.23 ± 0.36, 1.64 ± 0.14 and 0.99 ± 0.19, in lentil as 8.24 ± 1.11, 2.46 ± 0.06, 1.17 ± 0.19 and 1.01 ± 0.28 and in chickpea as 6.00 ± 1.40, 2.21 ± 0.14, 1.60 ± 0.43 and 0.58 ± 0.18 respectively. Copyright © 2005 Society of Chemical Industry
A phase I/II study of doxorubicin, ifosfamide, etoposide and interval methotrexate in patients with poor prognosis osteosarcoma
Authors: McTiernan Anne , Meyer Tim , Michelagnoli Maria P. , Lewis Ian , Whelan Jeremy S. 
Published: October 2005

AbstractBackgroundThe prognosis for patients with metastatic or axial‐skeletal osteosarcoma is poor. A phase I/II study was conducted of intensive chemotherapy with interval methotrexate, to assess the feasibility, response rate and toxicity in this group of patients.Patients and MethodsThirteen patients, median age 18 (range: 8–34), with metastatic or axial‐skeletal osteosarcoma were treated with ifosfamide 2.5 g/m2, etoposide 150 mg/m2, and doxorubicin 20 mg/m2 on days 1–3, every 21 days, with interval methotrexate 12 g/m2 given on day 14, for a maximum of eight cycles. Surgery to the primary was considered after four cycles for those with operable disease, or together with metastatic disease at completion of chemotherapy in those with inoperable tumours.ResultsA total of 85 cycles were given, median 6 per patient (range: 4–8). Only 6 of the 13 patients completed all 8 cycles of chemotherapy. Forty‐eight cycles (56%) required a dose reduction. The principal toxicity was myelosuppression, with a median nadir neutrophil count of 0.1 (range: 0–4.1). Grade 3 or 4 infection was seen in 41 cycles (48%). Histological response was assessable in seven patients, all of whom achieved a ≥90% necrosis. Radiological response rate, evaluable in seven patients with lung metastases, was 43%. All but one patient has had subsequent disease progression or relapse, with a median event free survival of 13 months (range: 5–53).ConclusionThis regimen was associated with responses, but these were not sustained. Substantial toxicity was seen, preventing optimal delivery. More effective, less toxic regimens are needed in this group of patients. Pediatr Blood Cancer © 2005 Wiley‐Liss, Inc.
Diagnosis and treatment of thrombosis in children: General principles
Authors: Young Guy 
Published: October 2005

AbstractThrombosis is an increasingly recognized complication occurring primarily in children with serious underlying conditions and most often associated with intravenous catheters. There are few clinical trials available to guide the decision‐making in the diagnosis and treatment of thrombosis. Although there are published guidelines which suggest how to manage such patients, they are based on data from adult studies and uncontrolled pediatric studies and it is unclear how widely these guidelines are utilized in clinical practice. What is clear is that many additional studies are needed to provide the data required to make evidence‐based decisions. Nevertheless, patients today are being diagnosed with thrombosis and must be treated. Diagnosis is based largely on various diagnostic‐imaging methods. While Doppler ultrasonography is non‐invasive and relatively inexpensive, its sensitivity for the upper venous system is poor. Venography/angiography, the most sensitive method to diagnose venous/arterial thrombosis is underutilized due to the need for peripheral venous access for venography and arterial catheterization for angiography as well as interventional radiology. Newer methods such as computed tomography and magnetic resonance imaging are useful for large vessel disease but are not validated in pediatrics. Treatment is based on the methods that are best at restoring circulation rapidly balanced by the risk for bleeding. Both thrombolysis and anticoagulation can be utilized with the circumstances of each individual patient dictating the choice. The field of pediatric thrombosis continues to advance with numerous new studies currently underway or being planned. In the near future, the results of these studies will allow for better management of pediatric patients with thrombosis. © 2005 Wiley‐Liss, Inc.
Cancer surveillance and control in adolescents—similarities and contrasts between Canada and the United States
Authors: Barr Ronald D. , Greenberg Mark L. 
Published: October 2005

AbstractOpportunities for cancer prevention in adolescents range from limitation of sun exposure to the use of human papillomavirus vaccines. Those who develop malignant disease experience longer waiting times for diagnosis and treatment than do children, especially when referred to adult treatment centers, and they are less frequently enrolled in clinical trials. More attention to developmentally appropriate psychological support, enhancement of compliance/adherence, health promotion, and palliative care is needed. Improving cancer surveillance and control in adolescents in North America will require co‐ordinated national efforts, involving pediatric and adult health care providers, institutions, and multiple levels of government. Pediatr Blood Cancer © 2005 Wiley‐Liss, Inc.
Dynamic light scattering of semidilute hydrophobically modified alkali‐soluble emulsion solutions with different lengths of poly(ethylene oxide) spacer chain
Authors: Dai Sheng , Chiu Tam Kam , Jenkins Richard D. 
Published: October 2005

AbstractSemidilute solutions of hydrophobically modified alkali‐soluble emulsion (HASE) were examined by dynamic light scattering and rheological techniques. For the model polymer without associative macromonomer, twoq2dependent diffusional modes were detected in the decay time distributions. With increasing hydrophobicity of the associative macromonomer, the narrow fast peak was substituted by a shallow broad peak and only oneq2dependent slow mode could be accurately detected, which indicated that the heterogeneity of these associated clusters increases with increasing carbon number. The bulk steady‐shear viscosity exhibits similar results to the diffusion coefficients of the aggregate observed from light scattering measurements. The length of poly(ethylene oxide) (PEO) spacer chain alters the solution properties as well as the associative cluster structure. With increasing length of PEO spacer chain, intramolecular association was substituted by intermolecular association. For EO segment larger than 32 units, intramolecular association dominates, where the formation of HASE aggregates is controlled by the balance of electrostatic repulsion and hydrophobic attraction. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3288–3298, 2005
A simplified method of preparing phosphoric acid for stable isotope analyses of carbonates
Authors: Burman Johan , Gustafsson Owe , Segl Monika , Schmitz Birger 
Published: October 2005

AbstractIn order to produce CO2 for stable isotope analyses (δ18O and δ13C), carbonate samples are commonly digested in phosphoric acid. The acid recipe here presented is based on phase shifting crystalline orthophosphoric acid of pro‐analysis quality to a liquid state through heating, followed by pre‐vacuum treatment during a start‐up procedure before mass analyses for common acid bath preparation, or adding a small amount of phosphoric pentoxide for single drop equipments, respectively. This methodology results in a final acid concentration of 104%. Copyright © 2005 John Wiley & Sons, Ltd.
Automated assignment of high‐resolution collisionally activated dissociation mass spectra using a systematic bond disconnection approach
Authors: Hill Alastair W. , Mortishire‐Smith Russell J. 
Published: October 2005

AbstractAn essential component of the process of characterising chemical unknowns via mass spectrometry is the analysis of collisionally activated dissociation (CAD) mass spectra. Existing tools for the automated assignment of CAD spectra typically use a rule‐based approach which identifies those bonds that are likely to break. While valuable, the failure of explicitly rule‐based approaches to suggest rationalisations for a significant proportion of observed product ions led us to develop an alternative approach (elucidation of product ion connectivity, EPIC) based on high‐resolution mass spectrometry, systematic bond disconnection of the precursor structure, and ranking of the resulting substructures. We exemplify this approach with a reanalysis of published MS/MS data for two compounds taken from the literature. Copyright © 2005 John Wiley & Sons, Ltd.
In vivo comparison of the reinforcing and dopamine transporter effects of local anesthetics in rhesus monkeys
Authors: Wilcox Kristin M. , Kimmel Heather L. , Lindsey Kimberly P. , Votaw John R. , Goodman Mark M. , Howell Leonard L. 
Published: October 2005

AbstractDopaminergic mechanisms are thought to play a central role in the reinforcing effects of cocaine. Similar to cocaine, other local anesthetics bind to the dopamine transporter (DAT) and inhibit DA uptake in rodent and monkey brain. Additionally, local anesthetics are self‐administered in rhesus monkeys, indicative of abuse liability. The present study examined the reinforcing and DAT effects of the local anesthetics dimethocaine, procaine and cocaine using in vivo techniques. Monkeys were trained to respond under a second‐order schedule for i.v. cocaine administration (0.10 or 0.30 mg/kg/infusion). When responding was stable, dimethocaine (0.030‐1.7 mg/kg/ infusion) or procaine (0.10‐10 mg/kg/ infusion) was substituted for the cocaine training dose. Dimethocaine administration produced higher response rates compared with that of procaine, and was a more potent reinforcer. Drug effects on behavior were related to DAT occupancy in monkey striatum during neuroimaging with positron emission tomography (PET). DAT occupancy was determined by displacement of 8‐(2‐[18F]fluroethyl)2β‐carbomethoxy‐3β‐(4‐chlorophenyl)nortropane (FECNT). DAT occupancy was between 66 and 82% and <10‐41% for doses of dimethocaine and procaine that maintained maximum response rates, respectively. Finally, in vivo microdialysis in awake subjects determined drug‐induced changes in extracellular DA in the caudate nucleus. There was close correspondence between peak increases in DA and DAT occupancy. Overall, reinforcing effects were consistent with DAT effects determined with in vivo techniques. The results further support a role for the DAT in the abuse liability of local anesthetics. Synapse 58:220–228, 2005. © 2005 Wiley‐Liss, Inc.
3,4‐Methylenedioxymethamphetamine (MDMA) enhances the release of acetylcholine by 5‐HT4and D1receptor mechanisms in the rat prefrontal cortex
Authors: Nair Sunila G. , Gudelsky Gary A. 
Published: October 2005

Abstract3,4‐Methylenedioxymethamphetamine (MDMA), an amphetamine analog, has been shown recently to increase the release of acetylcholine (ACh) in the prefrontal cortex (PFC). The present study further characterizes the stimulatory effect of MDMA on cortical ACh release and examines the role of serotonin (5‐HT) and dopamine (DA) receptors in this response. The extracellular concentration of ACh was increased dose‐dependently and similarly by the (+) and (−) enantiomers of MDMA (5 and 20 mg/kg, i.p.). The systemic administration of the 5‐HT4antagonist SDZ 205,557 (1 mg/kg, i.p.), but not the 5‐HT2A/2B/2Cantagonist LY‐53,857 (3 mg/kg, i.p.), significantly decreased cortical ACh release induced by MDMA. The MDMA‐induced increase in the extracellular concentration of ACh also was significantly blunted in rats treated with the D1receptor antagonist SCH 23390 (0.5 mg/kg, i.p.). The extent to which the coadministration of SDZ 205,557 and SCH 23390 suppressed the MDMA‐induced release of ACh in the PFC was no greater than that produced by either antagonist alone. These results suggest that the 5‐HT4and D1receptor subtypes contribute to the mechanism by which MDMA increases ACh release in the PFC. Synapse 58:229–235, 2005. © 2005 Wiley‐Liss, Inc.
Cesarean plus anoxia at birth induces hyperresponsiveness to locomotor activity by dopamine D2 agonist
Authors: Juárez Ismael , De La Cruz Fidel , Zamudio Sergio , Flores Gonzalo 
Published: October 2005

AbstractTransient global anoxia after Cesarean birth in rats may produce alterations in the subcortical DA function and related behaviors. The reports only tested the behavioral changes induced by a general DA agonist, such as amphetamine or apomorphine, in adult rats. Here we investigated the role of perinatal anoxia on the locomotion induced by a specific dopamine (DA) agonist and its relation to the DA D1‐like and D2‐like receptors, measured by autoradiography at two different ages, prepubertal (35 days old, P35) and postpubertal (60 days old, P60). Cesarean birth with or without (C‐only) an additional period of 10 min of the anoxia was done in Sprague‐Dawley rats, and the effects of the DA D1‐like and D2‐like agonist and their receptors were studied at P35 and P60. In addition, a third group of animals born vaginally served as the control. The quantitative autoradiography study of the DA D1‐like and D2‐like receptors revealed an enhancement of the DA D1‐like receptor levels in the nucleus accumbens (NAcc) and dorsolateral part of the caudate–putamen in the prepubertal C‐only animals. The postpubertal C‐only rats showed a decrease in the levels of DA D2‐like receptors in the NAcc. However, quinpirole, a DA D2 agonist (0.125 and 0.25 mg/kg, s.c.), induced a dose‐dependent increase of the locomotor activity in the animals born by Cesarean with anoxia at birth at both ages. Our results suggest that Cesarean with or without anoxia at birth may mediate differently the neurodevelopmental aspects of the dopaminergic system before and after puberty. Synapse 58:236–242, 2005. © 2005 Wiley‐Liss, Inc.
Temperature insensitivity of short‐term adaptation in single‐units of the chick cochlear nerve
Authors: Crumling Mark A. , Saunders James C. 
Published: October 2005

AbstractShort‐term adaptation in acoustically stimulated chick cochlear nerve fibers has recently been shown to have similar kinetics as the readily‐releasable vesicle pool in patch‐clamped chick hair cells, suggesting that short‐term adaptation depends on the dynamics of hair cell exocytosis. Our understanding of the relationship between these two phenomena has been hampered by differences in the temperatures at which the two types of data have been collected. In this report, the effect of temperature on short‐term adaptation was studied in single‐units of the chick cochlear nerve. Compared to units recorded at 38–41°C, spontaneous and evoked firing rates were markedly decreased when the temperature was lowered to 28–32°C, but the rate of short‐term adaptation during 100 ms tone bursts was relatively unchanged, with a temperature Q10, of ∼1.2. The continued similarity of the adaptation time‐constant of cooled units to vesicle depletion kinetics in chick hair cells measured at room temperature suggests that comparison of in vitro hair cell exocytosis and in vivo cochlear nerve firing properties may not be confounded by temperature differences between the two approaches. Synapse 58:243–248, 2005. © 2005 Wiley‐Liss, Inc.
N‐[18F]4′‐fluorobenzylpiperidin‐4yl‐(2‐fluorophenyl) acetamide ([18F]FBFPA): A potential fluorine‐18 labeled PET radiotracer for imaging sigma‐1 receptors in the CNS
Authors: Mach Robert H. , Gage H. Donald , Buchheimer Nancy , Huang Yunsheng , Kuhner Ross , Wu Li , Morton Thomas E. , Ehrenkaufer Richard L. 
Published: October 2005

AbstractA series of brain uptake studies and PET imaging studies were conducted with the σ1 selective imaging agent, [18F]FBFPA. The results of the study indicate that this radiotracer readily crosses the blood‐brain barrier and labels σ1 receptors in vivo. In vivo blocking studies with a σ1 selective ligand and a nonselective σ1/σ2 receptor ligand indicates that [18F]FBFPA labels σ1 and not σ2 receptors in rodent brain. PET imaging studies demonstrated a high uptake in regions of rhesus monkey brain having a high density of σ1 receptors. The uptake of [18F]FBFPA was displaced by the sigma ligand, haloperidol (1 mg/kg, i.v.). In vivo blocking studies indicate that the progesterone blocked the brain uptake of [18F]FBFPA in rat brain. These data indicate that [18F]FBFPA is a potential radiotracer for imaging σ1 receptors in the CNS in vivo with PET. Synapse 58:267–274, 2005. © 2005 Wiley‐Liss, Inc.