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HP
Terms modified by HP Selected AbstractsOptical studies of defects generated in neutron-irradiated Cz-Si during HP-HT treatmentCRYSTAL RESEARCH AND TECHNOLOGY, Issue 4-5 2005B. Surma Abstract Neutron-irradiated Czochralski grown silicon subjected to heat treatment (HT) at 350 °C and 1000 °C under enhanced hydrostatic pressure (HP) was studied in this work. It has been shown that external hydrostatic pressure enhances the creation of VO2 defects in neutron irradiated silicon subjected to the HP - HT treatment at 350 °C. Enhanced formation of platelet-like oxygen precipitates was found in the samples treated at 1000 °C under 1.1 GPa. This effect was more pronounced in the samples with VO2 defects. Presented results seem to suggest that probably HP helps to transform VO2 to some kind of defects or change alone VO2 defects in the form that can act as an additional nucleus for an additional oxygen precipitation at 1000°C. No correlation between the plate-like oxygen precipitates related absorption at 1225 cm -1 and dislocation-related emission has been confirmed. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Species-specific injury-induced cell proliferation in the hippocampus and subventricular zone of food-storing and nonstoring wild birdsDEVELOPMENTAL NEUROBIOLOGY, Issue 1 2010L.M. Law Abstract Cells are continuously born and incorporated into the adult hippocampus (HP). Adult neurogenesis might act to increase the total number of cells or replace dead cells. Thus, neurogenesis might be a primary factor in augmenting, maintaining, or even recovering functions. In zebra finches, HP injury increases cell proliferation in the HP and stem cell rich subventricular zone (SVZ). It is unknown what effect injury has on a species dependent upon the HP for survival in the wild. In food-storing birds, recovery of caches is seasonal, necessary for survival, dependent upon the HP and is concomitant with a peak in HP neurogenesis. During the fall, food-storing black-capped chickadees (BCCs) and nonstoring dark-eyed juncos (DEJs) were captured and given a unilateral penetrating lesion to the HP one day later. On day 3, birds were injected with the mitotic marker 5-bromo-2,-deoxyuridine (BrdU) and perfused on day 10. If unlesioned, more BrdU-labeled cells were observed in the HP and SVZ of BCCs compared to DEJs, indicating higher innate cell proliferation or incorporation in BCCs. If lesioned, BrdU-labeled cells increased in the injured HP of both species; however, lesions caused larger increases in DEJs. DEJs also showed increases in BrdU-labeled cells in the SVZ and contralateral HP. BCCs showed no such increases on day 10. Thus, during the fall food-storing season, storers showed suppressed injury-induced cell proliferation and/or reduced survival rates of these new cells compared to nonstorers. These species differences may provide a useful model for isolating factors involved in cellular responses following injury. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2010 [source] Hippocampal lesions impair spatial memory performance, but not song,A developmental study of independent memory systems in the zebra finchDEVELOPMENTAL NEUROBIOLOGY, Issue 8 2009David J. Bailey Abstract Songbirds demonstrate song- and spatial-learning, forms of memory that appear distinct in formal characteristics and fitting the descriptions and criteria of procedural and episodic-like memory function, respectively. As in other vertebrates, the neural pathways underlying these forms of memory may also be dissociable, and include the corresponding song circuit and hippocampus (HP). Whether (or not) these two memory systems interact is unknown. Interestingly, the HP distinguishes itself as a site of immediate early gene expression in response to song and as a site of estrogen synthesis, a steroid involved in song learning. Thus, an interaction between these memory systems and their anatomical substrates appears reasonable to hypothesize, particularly during development. To test this idea, juvenile male or female zebra finches received chemical lesions of the HP at various points during song learning, as did adults. Song structure, singing behavior, song preference, and spatial memory were tested in adulthood. Although lesions of the HP severely compromised HP-dependent spatial memory function across all ages and in both sexes, we were unable to detect any effects of HP lesions on song learning, singing, or song structure in males. Interestingly, females lesioned as adults, but not as juveniles, did lose the characteristic preference for their father's song. Since compromise of the neural circuits that subserve episodic-like memory does very little (if anything) to affect procedural-like (song learning) memory, we conclude that these memory systems and their anatomical substrates are well dissociated in the developing male zebra finch. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009 [source] The hippocampus and caudomedial neostriatum show selective responsiveness to conspecific song in the female zebra finchDEVELOPMENTAL NEUROBIOLOGY, Issue 1 2002David J. Bailey Abstract The perception of song is vital to the reproductive success of both male and female songbirds. Several neural structures underlying this perception have been identified by examining expression of immediate early genes (IEGs) following the presentation of conspecific or heterospecific song. In the few avian species investigated, areas outside of the circuit for song production contain neurons that are active following song presentation, specifically the caudal hyperstriatum ventrale (cHV) and caudomedial neostriatum (NCM). While studied in detail in the male zebra finch, IEG responses in these neural substrates involved in song perception have not been quantified in females. Therefore, adult female zebra finches were presented with zebra finch song, nonzebra finch song, randomly generated tones, or silence for 30 min. One hour later they were sacrificed, and their brains removed, sectioned, and immunocytochemically processed for FOS expression. Animals exposed to zebra finch song had a significantly higher density of FOS-immunoreactive cells in the NCM than those presented with other songs, tones, or silence. Neuronal activation in the cHV was equivalent in birds that heard zebra finch and non-zebra finch song, expression that was higher than that observed in the groups that heard no song. Interestingly, the hippocampus (HP) and adjacent parahippocampal area (AHP) were activated in a manner comparable to the NCM. These results suggest a general role for the cHV in song perception and a more specific role for the NCM and HP/AHP in facilitating recognition of and responsiveness to species-specific song in female zebra finches. © 2002 Wiley Periodicals, Inc. J Neurobiol 52: 43,51, 2002 [source] Children's narratives and patterns of cardiac reactivityDEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2004Yair Bar-Haim Abstract The present study examines the associations between narrative processing, narrative production, and cardiac rate and variability in children. Heart period (HP) and vagal tone (VT) were computed for fifty-eight 7-year-olds (29 males) during a resting baseline and during epochs in which the children listened to and completed a selected set of story-stems from the MacArthur Story-Stem Battery (I. Bretherton, D. Oppenheim, H. Buchsbaum, R. N. Emde, & the MacArthur Narrative Group, 1990). Significant decreases in HP and VT were observed between a resting baseline and epochs of story-stem presentation by the experimenter. In addition, HP was shorter and VT lower during children's narrative production to emotionally laden story-stems compared with narration to a neutral story-stem. Furthermore, narrative and cardiac responses to stories containing separation,reunion themes reflected increased emotional and cognitive load compared with responses to stories that did not contain such themes. Finally, children who showed VT suppression in response to emotion-laden stories produced more coherent and adaptive narratives compared to those of children who did not show VT suppression. The findings suggest interplay between the cognitive-emotional processes associated with narrative processing and production and cardiac activation patterns. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 44: 238,249, 2004. [source] Gastroesophageal reflux before and after Helicobacter pylori eradication.DISEASES OF THE ESOPHAGUS, Issue 4 2003A prospective study using ambulatory 24-h esophageal pH monitoring SUMMARY, The aim of this study was to assess prevalence of GERD before and after Helicobacter pylori (HP) eradication utilizing 24-h esophageal pH/manometry studies. Helicobacter pylori status was confirmed by the Campylobacter like organism test. Those testing positive underwent 24-h pH/manometry followed by HP eradication therapy and urea breath test. Patients were followed up at 6 months and then at 1 year when they underwent a repeat 24-h pH/manometry. Twenty patients, 10 with non-ulcer dyspepsia (NUD) and 10 with duodenal ulcer (DU) were enrolled, though only 10 patients attended for a repeat 24-h pH/manometry study. The patients were well matched, though patients with NUD had a significantly higher symptom score at entry compared with the DU group (8.5 vs 5.7, P < 0.05). The pH and esophageal manometry data were similar in the two groups. Overall nine patients (45%; DU = 5, NUD = 4) had evidence of GERD prior to HP eradication and it persisted one year after cure of the infection. The reflux disease occurred in the presence of normal LES pressure (mean 15.6 ± 3.3 mmHg). New onset GERD was uncommon after cure of HP infection, occurring in only one patient with NUD. Overall HP eradication had no impact on percentage of time pH < 4 (4.69 ± 3 vs 4.79 ± 3), episodes > 5 min (9.8 ± 16 vs 15.5 ± 25.3) and Johnson DeMeester Score (16.8 ± 7.5 vs 26.8 ± 18). In addition successful cure of HP produced no significant changes in LES pressure (17.9 ± 3.8 mmHg vs 19.3 ± 4.6 mmHg), and other esophageal manometry data. Half of HP-positive patients with NUD and DU have evidence of GERD before HP eradication. This persists after successful cure of the infection. New onset GERD occurs very uncommonly one year after HP eradication. [source] Phosphorus availability mediates plasticity in life-history traits and predator,prey interactions in DaphniaECOLOGY LETTERS, Issue 10 2005Punidan D. Jeyasingh Abstract We analysed growth plasticity of two Daphnia pulex clones under low-phosphorus (LP) and high phosphorus (HP) conditions, in the presence of Chaoborus kairomones to examine how food quality (P-availability) might impact life-history responses and vulnerability to predation. Overall, clone 1 grew faster, and was larger at maturity. Under HP, both clones responded to kairomones by increasing growth, age and size at maturity, and decreasing fecundity. Under LP, both clones suffered reduced growth, and fecundity. However, the magnitude of response to kairomones depended on a clone by P-availability interaction. Chaoborus presented a 1 : 1 clonal mixture under HP or LP, consumed more individuals under LP. Moreover, fewer clone 1 individuals were consumed. Studying the effects of P-availability on life histories, and predator,prey interactions may help us understand the mechanisms generating and maintaining plasticity, as well as influencing genotypic diversity and microevolutionary processes in natural populations. [source] Mr Drage, Mr Everyman, and the creation of a mass market for domestic furniture in interwar Britain1ECONOMIC HISTORY REVIEW, Issue 4 2009PETER SCOTT This article examines strategies used by durable goods retailers to create a mass market in interwar Britain, via a case study of domestic furniture. Interwar demand for new furniture witnessed particularly rapid growth,mainly owing to the extension of the market to lower-income groups. A number of innovative national retailers developed liberal hire purchase (HP) facilities in order to bring furniture within the economic reach of these groups, while sophisticated national advertising campaigns were used both to legitimize the buying of furniture on HP and to project the idea that furnishing by this means was key to achieving the type of aspirational lifestyles being promulgated in the popular media. [source] Analysis of amphetamine-type substances by capillary zone electrophoresis using capacitively coupled contactless conductivity detectionELECTROPHORESIS, Issue 15 2010Rochelle Epple Abstract CE with capacitively coupled contactless conductivity detection (C4D) was employed for the separation and detection of seven amphetamine analogues as well as amphetamine, dextroamphetamine, methamphetamine and 3,4-methylenedioxymethamphetamine. The separation electrolyte was 30,mM hydroxypropyl-,-cyclodextrin (HP,CD) in a 75,mM acetic acid+25,mM sodium acetate buffer adjusted to pH 4.55. Conductivity detection was compared with UV detection using this same electrolyte. Average detection limits for C4D and UV were 1.3 and 1.0,ppm, respectively. The effects of HP,CD concentration and BGE composition on the selectivity of the separation were also investigated. An illicit, street-grade sample of 3,4-methylenedioxymethamphetamine (Ecstasy) and a prescription dextroamphetamine tablet were also analysed. [source] Chiral separation of N -imidazole derivatives, aromatase inhibitors, by cyclodextrin-capillary zone electrophoresis.ELECTROPHORESIS, Issue 16 2004Mechanism of enantioselective recognition Abstract Baseline separation of ten new, substituted [1-(imidazo-1-yl)-1-phenylmethyl)] benzothiazolinone and benzoxazolinone derivatives with one chiral center was achieved using cyclodextrin-capillary zone electrophoresis (CD-CZE). A method for the enantiomeric resolution of these compounds was developed using neutral CDs (native ,-, ,-, ,-CDs or ,-, ,-, ,-hydroxypropyl (HP)-CDs) as chiral selectors. Operational parameters including the nature and concentration of the chiral selectors, pH, ionic strength, organic modifiers, temperature, and applied voltage were investigated. The use of neutral CDs provides enantiomeric resolution by inclusion of compounds in the CD cavity. The HP-,-CD and HP-,-CD were found to be the most effective complexing agents and allowed efficient enantiomeric resolutions. Optimal separation of N -imidazole derivatives was obtained using 50 mM phosphate buffer at pH 2.5 containing either HP-,-CD or HP-,-CD (7.5,12.5 mM) at 25°C, with an applied field of 0.50 kV·cm,1 giving resolution factors Rs superior to 1.70 with migration times of the second enantiomer less than 13 min. The same enantiomer migration order observed for all molecules can be related to a close interaction mechanism with CDs. The influence of structural features of the solutes on Rs and tm was studied. The lipophilic character (log kw) of the solutes and the apparent and averaged association constants of inclusion complexes for four compounds with the six different CDs led us to rationalize the enantioseparation mechanisms. The conclusions were corroborated with reversed-phase high-performance liquid chromatography (HPLC) on chiral stationary phases (CSPs) based on CDs. [source] Large-volume sample stacking combined with separation by 2-hydroxypropyl-,-cyclodextrin for analysis of isoxyzolylpenicillins by capillary electrophoresisELECTROPHORESIS, Issue 17 2003Zhiwei Zhu Abstract A simple, quick and sensitive capillary electrophoretic technique has been developed for the pharmaceutical analysis of isoxazolylpenicillins (oxacillin, cloxacillin and dicloxacillin) at trace levels for the first time. This method comprises large-volume sample stacking using the electroosmotic flow (EOF) pump (LVSEP), separation using 2-hydroxypropyl-,-cyclodextrin (HP-,-CD) as selective complex-forming background electrolyte additive, and direct UV detection. A complete resolution was achieved in the optimal background electrolyte containing 5.2 mM HP-,-CD. LVSEP was successfully applied in their determinations to improve the sensitivity, where the EOF in the buffer zone was suppressed by using an acidic buffer with pH 3.6. The detection limits of the current technique were found to be 2.0 ,g/L for each of the isoxazolylpenicillins based on the signal-to-noise ratio of 3. The curves of peak response versus concentration were linear from 5.0 to 400.0 ,g/L with regression coefficients of 0.9982, 0.9986 and 0.9976, respectively. The interaction of isoxazolylpenicillins with HP-,-CD was discussed. The association constants for complexes of HP-,-CD with isoxazolylpenicillins were determined by electrophoretic method. The obtained association constants were 27.3, 34.9, and 48.5 M,1, respectively, being proportional to their hydrophobic properties and steric hindrances. A simple and easy-manipulative sample preparation method was developed and validated by analyzing commercially available milk samples. It was found that with current sample preparation process and instrumentation system, 0.1 mL of milk sample is enough for the analysis of isoxazolylpenicillins to meet European Union (EU) guideline of 30 ,g/kg. [source] Outcome after hemispherectomy in hemiplegic adult patients with refractory epilepsy associated with early middle cerebral artery infarctsEPILEPSIA, Issue 6 2009Arthur Cukiert Summary Purpose:, To study the outcome after hemispherectomy (HP) in a homogeneous adult patient population with refractory hemispheric epilepsy. Methods:, Fourteen adult patients submitted to HP were studied. Patients had to be at least 18 years old, and have refractory epilepsy, clearly focal lateralized seizures and unilateral porencephalus consistent with early middle cerebral artery infarct on magnetic resonance imaging (MRI). All patients were submitted to functional hemispherectomy. We analyzed age of seizure onset, age by the time of surgery, gender, seizure type and frequency, interictal and ictal electroencephalography (EEG) findings, MRI and IQ scores preoperatively; seizure frequency, drug regimen, and IQ outcome were studied postoperatively. Results:, Mean follow-up was 64 months. All patients had frequent daily seizures preoperatively. All patients had unilateral simple partial motor seizures (SPS); 11 patients had secondarily generalized tonic,clonic (GTC) seizures and five patients had complex partial seizures (CPS), preoperatively. All patients had hemiplegia and hemianopsia. Twelve patients had unilateral EEG findings, and in two epileptic discharges were seen exclusively over the apparently normal hemisphere. Twelve patients were seizure-free after surgery and two patients had at least 90% improvement in seizure frequency. Pre- and postoperative mean general IQ was 84 and 88, respectively. Five of the twelve Engel I patients were receiving no drugs at last follow-up. There was no mortality or major morbidity. Conclusions:, Our results suggest that well-selected adult patients might also get good results after HP. Although good results were obtained in our adult series, the same procedure yielded a much more striking result if performed earlier in life. [source] The influence of strenuous exercise on collagen characteristics of articular cartilage in Thoroughbreds age 2 yearsEQUINE VETERINARY JOURNAL, Issue 6 2000P. A. J. BRAMA Summary In order to assess the influence of strenuous exercise on collagen characteristics of articularcartilage, the response of the collagen network was studied in seven 2-year-old Thoroughbreds subjected to strenuous exercise compared to 7 nontrained individuals. After 13 weeks, the animals were subjected to euthanasia, fetlock joints of the forelimbs were scored macroscopically after Indian Ink staining, and articular cartilage from different locations of the articular surface of the proximal first phalanx was sampled and analysed for water content, collagen content, hydroxylysine content and amount of hydroxylysylpyridinoline (HP) crosslinks. Gross lesions were significantly more severe in the exercised than in the nonexercised group. In the control animals, the characteristic site-specific differences in collagen parameters were found as described earlier, but in the strenuously exercised animals this physiological biochemical heterogeneity had disappeared. In the exercised animals, an increase in water content and a sharp decrease in HP crosslinking was found that was correlated with the presence of wear lines. It is concluded that the strenuous exercise provoked significant alterations in the characteristics of the collagen network of the articular cartilage of the fetlock joint which were suggestive of microdamage and loosening of the collagen network. The collagen component of cartilage, in contrast to the proteoglycan component, is known to have a very limited capacity for repairand remodelling due to an extremely low turnover rate. Therefore, alterations within the articular collagen network might be expected to play an important role in the pathophysiology of degenerative joint disorders. [source] Tolerance to non-opioid analgesics in PAG involves unresponsiveness of medullary pain-modulating neurons in male ratsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2009Victor Tortorici Abstract Opiate analgesia can be hampered by a reduction in pharmacological effectiveness (tolerance), and this crucially depends on the periaqueductal gray matter (PAG). Non-opioids like metamizol (dipyrone) or aspirin also induce PAG-dependent analgesia and tolerance, but the neuronal bases of this tolerance are unknown. Metamizol is a pyrazolon derivative and cyclooxygenase inhibitor with widespread use as an analgesic in Europe and Latin America. Metamizol was microinjected into the PAG of awake male rats, and antinociception was assessed by the tail flick (TF) and hot plate (HP) tests. Microinjection twice daily for 2.5 days caused tolerance to metamizol. The rats were then anesthetized and recordings from pain-facilitating on-cells and pain-inhibiting off-cells of the rostral ventromedial medulla (RVM) were performed. PAG microinjection of morphine or metamizol depresses on-cells, activates off-cells and thus inhibits nociception, including TF and HP. In metamizol-tolerant rats, however, PAG microinjection of metamizol failed to affect on- or off-cells, and this is interpreted as the reason for tolerance. In metamizol-tolerant rats morphine microinjection into PAG also failed to affect RVM neurons or nociception (cross-tolerance). In naïve, non-tolerant rats the antinociceptive effect of PAG-microinjected metamizol or morphine was blocked when CTOP, a ,-opioid antagonist, was previously microinjected into the same PAG site. These results emphasize a close relationship between opioid and non-opioid analgesic mechanisms in the PAG and show that, like morphine, tolerance to metamizol involves a failure of on- and off-cells to, respectively, disfacilitate and inhibit nociception. Cross-tolerance between non-opioid and opioid analgesics should be important in the clinical setting. [source] Elevated levels of collagen cross-link residues in gingival tissues and crevicular fluid of teeth with periodontal diseaseEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2003Søren Jepsen Lysylpyridinoline (LP) and hydroxylysylpyridinoline (HP) are collagen cross-link residues. Lysylpyridinoline is present in most tissues, whereas LP is present mainly in mineralized tissue. Both are elevated in tissue with increased collagen resorption. The purpose of this investigation was to assess if the concentrations of LP and HP are elevated in gingiva and gingival crevicular fluid (GCF) of teeth with advanced periodontitis (AP). We investigated human gingival biopsies of healthy teeth (n = 19) and teeth with AP (n = 43) in 49 individuals. Samples of GCF from 54 teeth with AP were collected in seven patients and compared with samples from 11 patients with experimentally induced gingivitis. Levels of LP and HP were measured by HPLC and fluorescence detection. Gingival concentrations of HP but not LP around teeth with advanced periodontitis were significantly elevated compared with teeth with healthy periodontium. While significant amounts of HP and LP were measurable in the GCF of teeth with AP, no HP and LP was identified 3 months following non-surgical periodontal therapy of the teeth or in fluid from teeth subjected to experimentally induced gingivitis. Elevated concentrations of HP and LP in GCF may serve as indicators of ongoing destruction of periodontal tissues and alveolar bone in advanced periodontitis. [source] Analysis of DNA-binding sites on Mhr1, a yeast mitochondrial ATP-independent homologous pairing proteinFEBS JOURNAL, Issue 6 2010Tokiha Masuda The Mhr1 protein is necessary for mtDNA homologous recombination in Saccharomyces cerevisiae. Homologous pairing (HP) is an essential reaction during homologous recombination, and is generally catalyzed by the RecA/Rad51 family of proteins in an ATP-dependent manner. Mhr1 catalyzes HP through a mechanism similar, at the DNA level, to that of the RecA/Rad51 proteins, but without utilizing ATP. However, it has no sequence homology with the RecA/Rad51 family proteins or with other ATP-independent HP proteins, and exhibits different requirements for DNA topology. We are interested in the structural features of the functional domains of Mhr1. In this study, we employed the native fluorescence of Mhr1's Trp residues to examine the energy transfer from the Trp residues to etheno-modified ssDNA bound to Mhr1. Our results showed that two of the seven Trp residues (Trp71 and Trp165) are spatially close to the bound DNA. A systematic analysis of mutant Mhr1 proteins revealed that Asp69 is involved in Mg2+ -dependent DNA binding, and that multiple Lys and Arg residues located around Trp71 and Trp165 are involved in the DNA-binding activity of Mhr1. In addition, in vivo complementation analyses showed that a region around Trp165 is important for the maintenance of mtDNA. On the basis of these results, we discuss the function of the region surrounding Trp165. [source] Calcium balance in Daphnia grown on diets differing in food quantity, phosphorus and calciumFRESHWATER BIOLOGY, Issue 11 2009XUE-JIA HE Summary 1.,The influences of dietary phosphorus (P) and food concentration on the calcium (Ca) balance in Daphnia magna were examined in this study at two different ambient Ca concentrations (0.5 and 10 mg Ca L,1). Daphnia were grown by feeding the young adults differentially under contrasting dietary P conditions [molar C : P ratio = c. 900 and c. 90 as low P (LP) and high P (HP), respectively], ambient Ca concentrations [0.5 mg and 10 mg Ca L,1 as low Ca (LCa) or high Ca (HCa), respectively] and food levels [0.15 or 1.5 mg C L,1 as low food (LF) or high food (HF), respectively] for 5 days. 2.,The specific Ca contents of daphniids (1.9,6.5% of dry weight,1) increased with increasing Ca concentration, food level and dietary P content, although the food level did not affect the Ca content in the HPHCa treatment. A radioactive tracer method showed that the food level did not affect the influx of Ca from the water under LP conditions, but the Ca influx under HP conditions doubled with a HF level. A LP condition also led to a decrease in Ca influx with a HF level. 3.,During the 3 days of efflux, generally only a small proportion of Ca (2.6,3.3%) was retained by the daphniids, but this retention increased (14,23%) under low ambient Ca concentrations and under P-limitation. Excretion was the most important pathway for Ca loss (accounting for 50,60% of body Ca), followed by moulting (20,47%), but the relative contribution of these two pathways (excretion and moulting) did not vary among all the different treatments. The absolute loss of Ca through excretion and moulting, on the contrary, differed with different ambient Ca concentrations and dietary P conditions. A HF level led to an increase in the loss rates in most cases. 4.,Our study strongly suggested that there is an interaction between an essential metal (Ca) and macronutrients (C and P) in freshwater crustaceans with HCa and P contents. The results imply that variation in environmental nutrient conditions may change the Ca budget in crustaceans and may affect the dynamics of Ca in the epilimnion of freshwaters. [source] Evaluation of gastric toxicity of indomethacin acid, salt form and complexed forms with hydroxypropyl-,-cyclodextrin on Wistar rats: histopathologic analysisFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 6 2009A.C. Ribeiro-Rama Abstract Indomethacin (IM) is a non-steroidal anti-inflammatory drug which inhibits prostaglandin biosynthesis. It is practically insoluble in water and has the capacity to induce gastric injury. Hydroxypropyl-,-cyclodextrin (HP-,-CD) is an alkylated derivative of ,-CD with the capacity to form inclusion complexes with suitable molecules. IM is considered to form partial inclusion complexes with HP-,-CD by enclosure of the p -chlorobenzoic part of the molecule in the cyclodextrin channel, reducing the adverse effects. The aim of this paper is to evaluate the gastric damage induced by the IM inclusion complex prepared by freeze-drying and spray-drying. A total of 135 Wistar rats weighing 224.4 ± 62.5 g were put into 10 groups. They were allowed free access to water but were maintained fasted for 18 h before the first administration until the end of the experiment. IM acid-form, IM trihydrated-sodium-salt and IM-HP-,-CD spray and freeze-dried, at normal and toxic doses, were administered through gastric cannula once/day for 3 days. Seventy-two hours after the first administration, the animals were sacrificed and the stomachs collected and prepared for morphological study by using the haematoxylin-eosin technique. Lesion indexes (rated 0/4) were developed and the type of injury was scored according to the severity of damage and the incidence of microscopic evidence of harm. Microscopic assessment demonstrated levels of injury with index one on 10,25%. The type of complexation method had different incidence but the same degree. The results show that IM inclusion complexation protects against gastric injury, reducing the incidence and the maximum degree of severity from 4 to 1, with a better performance of the spray-dried complex. [source] High-Pressure Synthesis of Tantalum Nitride Having Orthorhombic U2S3 StructureADVANCED FUNCTIONAL MATERIALS, Issue 14 2009Andreas Zerr Abstract Among binary compounds, there is a high potential for discovery of novel members (polymorphic phases or compounds) of the nitrides of transition metals group due to a pronounced dependence of the oxidation state of the metals (M) on pressure. The power of high pressure,high temperature (HP-HT) route for synthesis of binary nitrides has already been demonstrated by the discovery of cubic nitrides of the group 4 and 14 elements, of crystalline polymorphs of P3N5, and by reports on formation of four noble metal nitrides. It is anticipated that such HP products exhibit, in addition to enhanced elastic and mechanical behavior, other functional properties making them interesting for industrial applications. Here, HP,HT synthesis research is extended to nitrides of group 5 elements, resulting in the discovery of a novel hard tantalum nitride, exhibiting U2S3 structure: , -Ta2N3 (Pbnm, a,=,8.1911(17),Å, b,=,8.1830(17),Å, c,=,2.9823(3),Å). The stoichiometry is supported by two independent means, verifying that , -Ta2N3 is the first thermodynamically stable transition metal nitride with a N:M ratio exceeding 4:3. Due to its high hardness and peculiar texture (needle-like and granular crystallites), , -Ta2N3 may find practical applications as a hard fracture resistant material. [source] Teaching and Learning Guide for: Memoryscape: How Audio Walks Can Deepen Our Sense of Place by Integrating Art, Oral History and Cultural GeographyGEOGRAPHY COMPASS (ELECTRONIC), Issue 5 2008Toby Butler Author's Introduction This article is concerned with the history and practice of creating sound walks or ,memoryscapes': outdoor trails that use recorded sound and spoken memory played on a personal stereo or mobile media to experience places in new ways. It is now possible to cheaply and easily create this and other kinds of located media experience. The development of multi-sensory-located media (,locedia') presents some exciting opportunities for those concerned with place, local history, cultural geography and oral history. This article uses work from several different disciplines (music, sound art, oral history and cultural geography) as a starting point to exploring some early and recent examples of locedia practice. It also suggests how it might give us a more sophisticated, real, embodied and nuanced experience of places that the written word just can not deliver. Yet, there are considerable challenges in producing and experiencing such work. Academics used to writing must learn to work in sound and view or image; they must navigate difficult issues of privacy, consider the power relations of the outsider's ,gaze' and make decisions about the representation of places in work that local people may try and have strong feelings about. Creating such work is an active, multi-sensory and profoundly challenging experience that can offer students the chance to master multi-media skills as well as apply theoretical understandings of the histories and geographies of place. Author Recommends 1.,Perks, R., and Thomson, A. (2006). The oral history reader, 2nd ed. London: Routledge. This is a wonderful collection of significant writing concerned with oral history. Part IV, Making Histories features much of interest, including a thought-provoking paper on the challenges of authoring in sound rather than print by Charles Hardy III, and a moving interview with Graeme Miller, the artist who created the Linked walk mentioned in the memoryscape article. These only feature in the second edition. 2.,Cresswell, T. (2004). Place: a short introduction. Oxford, UK: Blackwell. A refreshingly clear and well-written guide to the different theoretical takes on what makes places , a good starting point for further reading. 3.,Carlyle, A. (ed.). (2008). Autumn leaves: sound and the environment in artistic practice. Paris, France: Double Entendre. This is a collection of short essays and examples of located sonic media art; it includes interviews with practitioners and includes Hildegard Westekamp's Soundwalking, a practical guide to leading students on a mute walk. Lots of thought provoking, applied reading material for students here. 4.,Blunt, A., et al. (eds) (2003). Cultural geography in practice. London: Arnold. A great book for undergraduate and postgraduate students , concepts explained and lots of examples of actually doing cultural geography. The chapter on mapping worlds by David Pinder is particularly useful in this context. 5.,Pinder, D. (2001). Ghostly footsteps: voices, memories and walks in the city. Ecumene 8 (1), pp. 1,19. This article is a thoughtful analysis of a Janet Cardiff sound walk in Whitechapel, East London. Online Materials http://www.memoryscape.org.uk This is my project website, which features two online trails, Dockers which explores Greenwich and the memories of the London Docks that are archived in the Museum of London, and Drifting which is a rather strange experiment-combining physical geography and oral history along the Thames at Hampton Court, but still makes for an interesting trail. Audio, maps and trails can be downloaded for free, so students with phones or iPods can try the trails if you are within reach of Surrey or London. The site features an online version, with sound-accompanying photographs of the location. http://www.portsofcall.org.uk This website has three more trails here, this time of the communities surrounding the Royal Docks in East London. The scenery here is very dramatic and anyone interested in the regeneration of East London and its impact on local communities will find these trails interesting. Like Dockers, the walks feature a lot of rare archive interviews. This project involved a great deal of community interaction and participation as I experimented with trying to get people involved with the trail-making process. The site uses Google maps for online delivery. http://www.soundwalk.com This New York-based firm creates exceptionally high-quality soundwalks, and they are well worth the money. They started by producing trails for different districts of New York (I recommend the Bronx Graffiti trail) and have recently made trails for other cities, like Paris and Varanassi in India. http://www.mscapers.com This website is run by Hewlett Packard, which has a long history of research and development in located media applications. They currently give free licence to use their mscape software which is a relatively easy to learn way of creating global positioning system-triggered content. The big problem is that you have to have a pricey phone or personal digital assistant to run the software, which makes group work prohibitively expensive. But equipment prices are coming down and with the new generations of mobile phones developers believe that the time when the player technology is ubiquitous might be near. And if you ask nicely HP will lend out sets of equipment for teaching or events , fantastic if you are working within reach of Bristol. See also http://www.createascape.org.uk/ which has advice and examples of how mscape software has been used for teaching children. Sample Syllabus public geography: making memoryscapes This course unit could be adapted to different disciplines, or offered as a multidisciplinary unit to students from different disciplines. It gives students a grounding in several multi-media techniques and may require support/tuition from technical staff. 1.,Introduction What is a located mediascape, now and in the future? Use examples from resources above. 2.,Cultural geographies of site-specific art and sound Theories of place; experiments in mapping and site-specific performance. 3.,Walk activity: Westergard Hildekamp , sound walk, or one of the trails mentioned above The best way , and perhaps the only way , to really appreciate located media is to try one in the location they have been designed to be experienced. I would strongly advise any teaching in this field to include outdoor, on-site experiences. Even if you are out of reach of a mediascape experience, taking students on a sound walk can happen anywhere. See Autumn Leaves reference above. 4.,Researching local history An introduction to discovering historical information about places could be held at a local archive and a talk given by the archivist. 5.,Creating located multimedia using Google maps/Google earth A practical exercise-based session going through the basics of navigating Google maps, creating points and routes, and how to link pictures and sound files. 6.,Recording sound and oral history interviews A practical introduction to the techniques of qualitative interviewing and sound recording. There are lots of useful online guides to oral history recording, for example, an online oral history primer http://www.nebraskahistory.org/lib-arch/research/audiovis/oral_history/index.htm; a more in depth guide to various aspects of oral history http://www.baylor.edu/oral%5fhistory/index.php?id=23566 or this simple oral history toolkit, with useful links to project in the North of England http://www.oralhistorynortheast.info/toolkit/chapter1.htm 7.,Sound editing skills Practical editing techniques including working with clips, editing sound and creating multi-track recordings. The freeware software Audacity is simple to use and there are a lot of online tutorials that cover the basics, for example, http://www.wikieducator.org/user:brentsimpson/collections/audacity_workshop 8.,Web page design and Google maps How to create a basic web page (placing pictures, text, hyperlinks, buttons) using design software (e.g. Dreamweaver). How to embed a Google map and add information points and routes. There is a great deal of online tutorials for web design, specific to the software you wish to use and Google maps can be used and embedded on websites free for non-profit use. http://maps.google.com/ 9,and 10. Individual or group project work (staff available for technical support) 11.,Presentations/reflection on practice Focus Questions 1What can sound tell us about the geographies of places? 2When you walk through a landscape, what traces of the past can be sensed? Now think about which elements of the past have been obliterated? Whose past has been silenced? Why? How could it be put back? 3Think of a personal or family story that is significant to you. In your imagination, locate the memory at a specific place. Tell a fellow student that story, and describe that place. Does it matter where it happened? How has thinking about that place made you feel? 4What happens when you present a memory of the past or a located vision of the future in a present landscape? How is this different to, say, writing about it in a book? 5Consider the area of this campus, or the streets immediately surrounding this building. Imagine this place in one of the following periods (each group picks one): ,,10,000 years ago ,,500 years ago ,,100 years ago ,,40 years ago ,,last Thursday ,,50 years time What sounds, voices, stories or images could help convey your interpretation of this place at that time? What would the visitor hear or see today at different points on a trail? Sketch out an outline map of a located media trail, and annotate with what you hear/see/sense at different places. Project Idea small group project: creating a located mediascape Each small group must create a located media experience, reflecting an aspect of the history/geography/culture of an area of their choosing, using the knowledge that they have acquired over the course of the semester. The experience may be as creative and imaginative as you wish, and may explore the past, present or future , or elements of each. Each group must: ,,identify an area of interest ,,research an aspect of the area of the groups choosing; this may involve visiting local archives, libraries, discussing the idea with local people, physically exploring the area ,,take photographs, video or decide on imagery (if necessary) ,,record sound, conduct interviews or script and record narration ,,design a route or matrix of media points The final project must be presented on a website, may embed Google maps, and a presentation created to allow the class to experience the mediascape (either in the classroom or on location, if convenient). The website should include a brief theoretical and methodological explanation of the basis of their interpretation. If the group cannot be supported with tuition and support in basic website design or using Google mapping with sound and imagery, a paper map with locations and a CD containing sound files/images might be submitted instead. For examples of web projects created by masters degree students of cultural geography at Royal Holloway (not all sound based) see http://www.gg.rhul.ac.uk/MA/web-projects.html [source] Making a profit , and a difference: HP invents an organization to drive sustainabilityGLOBAL BUSINESS AND ORGANIZATIONAL EXCELLENCE, Issue 3 2004Walt Rosenberg More companies are realizing that doing well and doing good are not mutually exclusive. The merger of Hewlett-Packard and Compaq has produced an innovative organizational model for addressing corporate, social, and environmental responsibility (CSER). HP's CSER group integrates these seemingly disparate functions and relies on influence rather than control to make sustainability a way of life at HP. © 2004 Hewlett-Packard Development Company, L.P. [source] Modeled interactive effects of precipitation, temperature, and [CO2] on ecosystem carbon and water dynamics in different climatic zonesGLOBAL CHANGE BIOLOGY, Issue 9 2008YIQI LUO Abstract Interactive effects of multiple global change factors on ecosystem processes are complex. It is relatively expensive to explore those interactions in manipulative experiments. We conducted a modeling analysis to identify potentially important interactions and to stimulate hypothesis formulation for experimental research. Four models were used to quantify interactive effects of climate warming (T), altered precipitation amounts [doubled (DP) and halved (HP)] and seasonality (SP, moving precipitation in July and August to January and February to create summer drought), and elevated [CO2] (C) on net primary production (NPP), heterotrophic respiration (Rh), net ecosystem production (NEP), transpiration, and runoff. We examined those responses in seven ecosystems, including forests, grasslands, and heathlands in different climate zones. The modeling analysis showed that none of the three-way interactions among T, C, and altered precipitation was substantial for either carbon or water processes, nor consistent among the seven ecosystems. However, two-way interactive effects on NPP, Rh, and NEP were generally positive (i.e. amplification of one factor's effect by the other factor) between T and C or between T and DP. A negative interaction (i.e. depression of one factor's effect by the other factor) occurred for simulated NPP between T and HP. The interactive effects on runoff were positive between T and HP. Four pairs of two-way interactive effects on plant transpiration were positive and two pairs negative. In addition, wet sites generally had smaller relative changes in NPP, Rh, runoff, and transpiration but larger absolute changes in NEP than dry sites in response to the treatments. The modeling results suggest new hypotheses to be tested in multifactor global change experiments. Likewise, more experimental evidence is needed for the further improvement of ecosystem models in order to adequately simulate complex interactive processes. [source] Impact of land use and land cover change on groundwater recharge and quality in the southwestern USGLOBAL CHANGE BIOLOGY, Issue 10 2005Bridget R. Scanlon Abstract Humans have exerted large-scale changes on the terrestrial biosphere, primarily through agriculture; however, the impacts of such changes on the hydrologic cycle are poorly understood. The purpose of this study was to test the hypothesis that the conversion of natural rangeland ecosystems to agricultural ecosystems impacts the subsurface portion of the hydrologic cycle by changing groundwater recharge and flushing salts to underlying aquifers. The hypothesis was examined through point and areal studies investigating the effects of land use/land cover (LU/LC) changes on groundwater recharge and solute transport in the Amargosa Desert (AD) in Nevada and in the High Plains (HP) in Texas, US. Studies use the fact that matric (pore-water-pressure) potential and environmental-tracer profiles in thick unsaturated zones archive past changes in recharging fluxes. Results show that recharge is related to LU/LC as follows: discharge through evapotranspiration (i.e., no recharge; upward fluxes <0.1 mm yr,1) in natural rangeland ecosystems (low matric potentials; high chloride and nitrate concentrations); moderate-to-high recharge in irrigated agricultural ecosystems (high matric potentials; low-to-moderate chloride and nitrate concentrations) (AD recharge: ,130,640 mm yr,1); and moderate recharge in nonirrigated (dryland) agricultural ecosystems (high matric potentials; low chloride and nitrate concentrations, and increasing groundwater levels) (HP recharge: ,9,32 mm yr,1). Replacement of rangeland with agriculture changed flow directions from upward (discharge) to downward (recharge). Recent replacement of rangeland with irrigated ecosystems was documented through downward displacement of chloride and nitrate fronts. Thick unsaturated zones contain a reservoir of salts that are readily mobilized under increased recharge related to LU/LC changes, potentially degrading groundwater quality. Sustainable land use requires quantitative knowledge of the linkages between ecosystem change, recharge, and groundwater quality. [source] The influence of strain of Holstein-Friesian dairy cow and pasture-based feeding system on grazing behaviour, intake and milk productionGRASS & FORAGE SCIENCE, Issue 1 2007S. McCarthy Abstract A comparative study of grazing behaviour, herbage intake and milk production of three strains of Holstein-Friesian dairy cow was conducted using three grass-based feeding systems over two years. The three strains of Holstein-Friesian cows were: high production North American (HP), high durability North American (HD) and New Zealand (NZ). The three grass-based feeding systems were: high grass allowance (MP), high concentrate (HC) and high stocking rate (HS). In each year seventy-two pluriparous cows, divided equally between strains of Holstein-Friesian and feeding systems were used. Strain of Holstein-Friesian cow and feeding system had significant effects on grazing behaviour, dry matter (DM) intake and milk production. The NZ strain had the longest grazing time while the HD strain had the shortest. The grazing time of cows in the HC system was shorter than those in both the HS and MP systems. There was a significant strain of Holstein-Friesian cow by feeding system interaction for DM intake of grass herbage and milk production. The NZ strain had the highest substitution rate with the HP strain having the lowest. Hence, response in milk production to concentrate was much greater with the HP than the NZ strain. Reduction in milk yield as a consequence of a higher stocking rate (MP vs. HS system) was, however, greater for the HP and HD strains compared with the NZ strain. The results suggest that differences in grazing behaviour are important in influencing DM intake and milk production. [source] Safety and efficacy of solvent/detergent-treated antihaemophilic factor with an added 80 °C terminal dry heat treatment in patients with haemophilia AHAEMOPHILIA, Issue 3 2000J. S. Powell Plasma-derived factor VIII concentrates remain an important resource for haemophilia A patients. To improve the safety of these preparations, various methods of viral removal and inactivation have been used that are designed to eliminate both enveloped and non-enveloped viruses. There have been rare reports that some viral inactivation processes altered the immunogenicity of some concentrates, leading to the development of factor VIII inhibitors in previously treated haemophilia A patients. This study evaluated the safety, efficacy and lack of neo-antigenicity of a highly purified factor VIII preparation which undergoes both solvent/detergent treatment and final dry heat treatment at 80 °C for 72 h. The study included: (i) a single blind, single-dose crossover pharmacokinetic study in 18 previously treated patients, comparing sibling lots of the unheated preparation (Koate® -HP) and the heat-treated preparation (Koate® -DVI), and (ii) an extended home treatment programme for 36 patients at two haemophilia treatment centres primarily to assess immunogenicity. Clinical parameters were assessed at regular intervals. The results confirm that Koate® -HP and Koate® -DVI are bioequivalent, and that Koate® -DVI is safe and efficacious for treatment of acute bleeding episodes and for surgery. Furthermore, the heat-treated preparation is not associated with the development of inhibitors in previously treated patients. [source] Synthesis, Spectroscopy, and Hydroformylation Activity of Sterically Demanding, Phosphite-Modified Cobalt CatalystsHELVETICA CHIMICA ACTA, Issue 3 2005Reinout Meijboom The dinuclear complex [Co2(CO)6{P(O-2,4- t -Bu2C6H3)3}2] (6) has been synthesised and fully characterised. X-Ray crystal-structure analysis revealed a trans -diaxial geometry, no bridging carbonyls, and CoCo and CoP bond lengths of 2.706(5) and 2.134(4),Å, respectively. The hydroformylation of pent-1-ene in the presence of 6 was studied at 120,180° at pressures between 20 and 80,bar Syngas. High-pressure (HP) spectroscopy (IR, NMR) was used to detect potential hydride intermediates. HP-IR Studies revealed the formation of [CoH(CO)3{P(O-2,4- t -Bu2C6H3)3}] (2) at ca. 105°, with no significant amount of [CoH(CO)4] detectable. The intermediate 2 was synthesised and characterised. The formation of the undesired complex [CoH(CO)2{P(O-2,4- t -Bu2C6H3)3}2] was completely suppressed due to the large cone angle of the sterically demanding phosphite. [source] Advanced colorectal polyps with the molecular and morphological features of serrated polyps and adenomas: concept of a ,fusion' pathway to colorectal cancerHISTOPATHOLOGY, Issue 2 2006J R Jass Aim :,To establish and explain the pattern of molecular signatures across colorectal polyps. Methods and results :,Thirty-two sessile serrated adenomas (SSA), 10 mixed polyps (MP), 15 traditional serrated adenomas (SA), 49 hyperplastic polyps (HP) and 84 adenomas were assessed for mutation of KRAS and BRAF and aberrant expression of p53. The findings were correlated with loss of expression of O-6-methylguanine DNA methyltransferase (MGMT). KRAS mutation occurred more frequently (26.5%) than BRAF mutation (4.8%) in adenomas (P < 0.001) and particularly in adenomas with villous architecture (50%). Loss of expression of MGMT correlated with KRAS mutation in small tubular adenomas (P < 0.04). BRAF mutation was frequent in HPs (67%) and SSAs (81%), while KRAS mutation was infrequent (4% and 3%, respectively). Of MPs and SAs, 72% had either BRAF or KRAS mutation. Aberrant expression of p53 was uncommon overall, but occurred more frequently in MPs and SAs (12%) than adenomas (1%) (P < 0.04) and there was concordant loss of expression of MGMT. Conclusions :,Molecular alterations that are characteristic of the serrated pathway and adenoma,carcinoma sequence can co-occur in a minority of advanced colorectal polyps that then show morphological features of both pathways. These lesions account for only 2% of colorectal polyps, but may be relatively aggressive. [source] Haemosuccus pancreaticus: diagnostic and therapeutic challengesHPB, Issue 4 2009Velayutham Vimalraj Abstract Background:, Haemosuccus pancreaticus (HP) is a rare cause of upper gastrointestinal bleeding. The objective of our study was to highlight the challenges in the diagnosis and management of HP. Methods:, The records of 31 patients with HP diagnosed between January 1997 and June 2008 were reviewed retrospectively. Results:, Mean patient age was 34 years (11,55 years). Twelve patients had chronic alcoholic pancreatitis, 16 had tropical pancreatitis, two had acute pancreatitis and one had idiopathic pancreatitis. Selective arterial embolization was attempted in 22 of 26 (84%) patients and was successful in 11 of the 22 (50%). Twenty of 31 (64%) patients required surgery to control bleeding after the failure of arterial embolization in 11 and in an emergent setting in nine patients. Procedures included distal pancreatectomy and splenectomy, central pancreatectomy, intracystic ligation of the blood vessel, and aneurysmal ligation and bypass graft in 11, two, six and one patients, respectively. There were no deaths. Length of follow-up ranged from 6 months to 10 years. Conclusions:, Upper gastrointestinal bleeding in a patient with a history of chronic pancreatitis could be caused by HP. Diagnosis is based on investigations that should be performed in all patients, preferably during a period of active bleeding. These include upper digestive endoscopy, contrast-enhanced computed tomography (CECT) and selective arteriography of the coeliac trunk and superior mesenteric artery. Contrast-enhanced CT had a high positive yield comparable with that of selective angiography in our series. Therapeutic options consist of selective embolization and surgery. Endovascular treatment can control unstable haemodynamics and can be sufficient in some cases. However, in patients with persistent unstable haemodynamics, recurrent bleeding or failed embolization, surgery is required. [source] The application of change management theory to HR portal implementation in subsidiaries of multinational corporationsHUMAN RESOURCE MANAGEMENT, Issue 1 2005Cataldo Dino Ruta HR portals are complex information technology (IT) applications that can be accessed by all employees of a given organization. By placing more applications and information online, HR portals reduce the reliance employees have on HR personnel. Given this relational change, from human to computer, the HR portal implementation process must take into account the challenges of both change management and technology acceptance. By integrating change management theories with IT user acceptance models, this article adds to HR's collective knowledge of ways to effectively implement HR portals. In addition, this article describes the cross-national challenges that exist when a global firm attempts to implement an HR portal around the world. Thus, this article will present a model that (1) integrates change management theories and IT user acceptance models and (2) illustrates the ways in which change management plans may need to be adapted to be effective in various subsidiaries. A case study of Hewlett-Packard's (HP's) worldwide implementation of their @HP Employee Portal in the Italian subsidiary of HP illustrates the key issues of these theories. © 2005 Wiley Periodicals, Inc. [source] Heteropolymer-mediated clearance of immune complexes via erythrocyte CR1: mechanisms and applicationsIMMUNOLOGICAL REVIEWS, Issue 1 2001Margaret A. Lindorfer Summary: Opsonization of particulate pathogens by antibodies and complement can lead to their binding to the complement receptor (CR1), specific for C3b, on primate erythrocytes (E). This process of immune adherence may play a role in immunologic defense by immobilizing bacteria and viruses, thus preventing them from leaving the bloodstream to invade susceptible tissue and organs. Immune adherence of C3b-opsonized and immune complexed pathogens to E may also facilitate their transfer to, and destruction by, fixed tissue macrophages. We have used mAbs specific for CR1 crosslinked with pathogen specific mAbs to generate heteropolymers (HP) which can bind a wide range of substrates to primate erythrocytes. Both prototype and bonafide pathogens bound to primate E via HP are handled in the circulation of non-human primates in a manner which appears to be virtually identical to the mechanism by which C3b-opsonized substrates bound to E CR1 are cleared. In this process of focused phagocytosis, Fc receptors on the phagocytic cell engage the E-bound complex, CR1 is removed by proteolysis, and the entire immune complex and CR1 are internalized while sparing the E. It may be possible to use HP to target pathogens in the bloodstream in a wide range of therapeutic applications. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||