bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of bisphosphonates and titanium particles on osteoblasts
Authors: Peter B. , Zambelli P.-Y. , Guicheux J. , Pioletti D. P.
Published: July 2005

In an attempt to increase the life of cementless prostheses, an hydroxyapatite-coated implant which releases a bisphosphonate has been suggested as a drug-delivery system. Our in vitro study was designed to determine the maximum dose to which osteoblasts could be safely exposed.

Our findings demonstrated that zoledronate did not impair the proliferation of human osteoblasts when used at concentrations below 1 μm. Murine cells can be exposed to concentrations as high as 10 μm.

A concentration of 0.01% of titanium particles did not impair the proliferation of either cell line. Zoledronate affected the alkaline phosphatase activity of murine osteoblasts through a chelation phenomenon. The presence of titanium particles strongly decreased the alkaline phosphatase activity of murine osteoblasts. We did not detect any synergic effect of zoledronate and titanium particles on the behaviour of both human and murine osteoblasts.
Revision surgery for nonunion after early failure of fixation of fractures of the distal humerus
Authors: Ali A. , Douglas H. , Stanley D.
Published: July 2005

Sixteen patients who underwent a revision operation for nonunion of fractures of the distal humerus following previous internal fixation were reviewed at a mean follow-up of 39 months (8 to 69).

The Mayo elbow performance score was excellent in 11, good in two, fair in two and poor in one. In 15 patients union was achieved and in one with an infected nonunion a subsequent bone graft was necessary in order to obtain union.

Age, gender, a history of smoking, mechanism of the injury and the AO classification of the initial fracture did not correlate with the development of nonunion. In 12 patients (75%), the initial fixation was assessed as being suboptimal. The primary surgery was regarded as adequate in only three patients. Our findings suggest that the most important determinant of nonunion of a distal humeral fracture after surgery is the adequacy of fixation.
Continuous passive motion in the prevention of deep-vein thrombosis
Authors: Fuchs S. , Heyse T. , Rudofsky G. , Gosheger G. , Chylarecki C.
Published: July 2005

There is a high risk of venous thromboembolism when patients are immobilised following trauma. The combination of low-molecular-weight heparin (LMWH) with graduated compression stockings is frequently used in orthopaedic surgery to try and prevent this, but a relatively high incidence of thromboembolic events remains. Mechanical devices which perform continuous passive motion imitate contractions and increase the volume and velocity of venous flow.

In this study 227 trauma patients were randomised to receive either treatment with the Arthroflow device and LMWH or only with the latter. The Arthroflow device passively extends and plantarflexes the feet. Patients were assessed initially by venous-occlusion plethysmography, compression ultrasonography and continuous wave Doppler, which were repeated weekly without knowledge of the category of randomisation. Those who showed evidence of deep-vein thrombosis underwent venography for confirmation. The incidence of deep-vein thrombosis was 25% in the LMWH group compared with 3.6% in those who had additional treatment with the Arthroflow device (p < 0.001). There were no substantial complications or problems of non-compliance with the Arthroflow device. Logistic regression analysis of the risk factors of deep-vein thrombosis showed high odds ratios for operation (4.1), immobilisation (4.3), older than 40 years of age (2.8) and obesity (2.2).
The bicompartmental acetabulum in Perthes’ disease
Authors: Cho T.-J. , Choi I. H. , Chung C. Y. , Yoo W. J. , Lee K. S.
Published: July 2005

The bicompartmental acetabulum is one of the morphological changes which may be seen in children with Legg-Calvé-Perthes’ disease. Three-dimensional CT and MRI were used to analyse the detailed morphology of the acetabulum with special reference to its inner surface, in 16 patients with Perthes’ disease and a bicompartmental acetabulum.

The bicompartmental appearance was seen on the coronal plane image through the acetabular fossa. The lunate surface was seen to grow laterally resulting in an increased mediolateral thickness of the triradiate cartilage. On the horizontal plane images, the acetabular fossa had deepened and had a distinct prominence at its posterior border. The combination of these morphological changes resulted in a bicompartmental appearance on plain radiography. Acetabular bicompartmentalisation appears to be the result of an imbalance of growth between the cartilage-covered lunate surface and the cartilage-devoid acetabular fossa.
Prostaglandin EP4 receptor agonist augments fixation of hydroxyapatite-coated implants in a rat model of osteoporosis
Authors: Hayashi K. , Fotovati A. , Ali S. A. , Oda K. , Oida H. , Naito M.
Published: July 2005

The reduced stability of hydroxyapatite (HA)-coated implants in osteopenic conditions is considered to be a major problem. We therefore developed a model of a boosted cementless implantation in osteopenic rats.

Twelve-week-old rats were either ovariectomised (OVX) or sham-operated (SO), and after 24 weeks plain or HA-coated implants were inserted. They were treated with either a prostaglandin EP4 receptor agonist (ONO-4819) or saline for one month.

The EP4 agonist considerably improved the osteoporosis in the OVX group. Ultrastructural analysis and mechanical testing showed an improvement in the implant-bone attachment in the HA-coated implants, which was further enhanced by the EP4 agonist. Although the stability of the HA-coated implants in the saline-treated OVX rats was less than in the SO normal rats, the administration of the EP4 agonist significantly compensated for this shortage. Our results showed that the osteogenic effect of the EP4 agonist augmented the osteoconductivity of HA and significantly improved the stability of the implant-bone attachment in the osteoporotic rat model.
Outcome of revision hip arthroplasty in patients with a previous total hip replacement for developmental dysplasia of the hip
Authors: Morag G. , Zalzal P. , Liberman B. , Safir O. , Flint M. , Gross A. E.
Published: July 2005

Our aim was to determine if the height of the cup, lateralisation or the abduction angle correlated with functional outcome or survivorship in revision total hip replacement in patients with a previous diagnosis of developmental dysplasia of the hip. A retrospective investigation of 51 patients (63 hips) who had undergone revision total hip replacement was performed. The mean duration of follow-up was 119 months. Forty-one patients (52 hips) were available for both determination of functional outcome and survivorship analysis. Ten patients (11 hips) were only available for survivorship analysis.

The height of the cup was found to have a statistically significant correlation with functional outcome and a high hip centre correlated with a worse outcome score. Patients with a hip centre of less than 3.5 cm above the anatomical level had a statistically better survivorship of the cup than those with centres higher than this. Restoration of the height of the centre of the hip to as near the anatomical position as possible improved functional outcome and survivorship of the cup.
Results of a hydroxyapatite-coated (Furlong) total hip replacement
Authors: Shetty A. A. , Slack R. , Tindall A. , James K. D. , Rand C.
Published: July 2005

We describe the survival of 134 consecutive JRI Furlong hydroxyapatite-coated uncemented total hip replacements. The mean follow-up was for 14.2 years (13 to 15).

Patients were assessed clinically, using the Merle d’Aubigné and Postel score. Radiographs were evaluated using Gruen zones for the stem and DeLee and Charnley zones for the cup. Signs of subsidence, radiolucent lines, endosteal bone formation (spot welds) and pedestal formation were used to assess fixation and stability of the stem according to Engh’s criteria. Cup angle, migration and radiolucency were used to assess loosening of the cup. The criteria for failure were revision, or impending revision because of pain or loosening. Survival analysis was performed using a life table and the Kaplan-Meier curve.

The mean total Merle d’Aubigné and Postel score was 7.4 pre-operatively and 15.9 at follow-up. During the study period 22 patients died and six were lost to follow-up. None of the cups was revised. One stem was revised for a periprosthetic fracture following a fall but none was revised for loosening, giving a 99% survival at 13 years. Our findings suggest that the long-term results of these hydroxyapatite-coated prostheses are more than satisfactory.
Correlation of the condition of the patellar articular cartilage and patellofemoral symptoms and function in osteoarthritic patients undergoing total knee arthroplasty
Authors: Han I. , Chang C. B. , Lee S. , Lee M. C. , Seong S. C. , Kim T. K.
Published: July 2005

We sought to determine the degree of correlation between the condition of the patellar articular cartilage and patellofemoral symptoms and function in osteoarthritic patients undergoing total knee arthroplasty. The depth of the osteoarthritic lesion, as graded by the Outerbridge classification and its size and location were assessed to determine the condition of the patellar cartilage in 80 consecutive osteoarthritic knees undergoing total knee arthroplasty. The association between the condition of the cartilage and patellofemoral symptoms and function was investigated by correlation analysis.

The depth and size of the lesion had a significant but weak correlation with anterior knee pain (r = −0.300 and −0.289; p = 0.007 and 0.009, respectively), whereas location had no significant association (p > 0.05). None had a significant association with patellofemoral functional parameters (chair-rising, stair-climbing, and quadriceps power) (p > 0.05).

Our study indicates that patellofemoral symptoms and function are not completely determined by the condition of the cartilage. Caution should be taken when the symptoms and functional limitations are attributed to a lesion in the patellofemoral joint in making a decision regarding patellar resurfacing in total knee arthroplasty.
Delay to surgery prolongs hospital stay in patients with fractures of the proximal femur
Authors: Siegmeth A. W. , Gurusamy K. , Parker M. J.
Published: July 2005

Previous studies on the timing of surgery for fracture of the hip provide conflicting evidence as to the effect of prolonged delay before operation. We have prospectively reviewed 3628 such fractures in patients older than 60 years of age. Those for whom the delay was for medical reasons were excluded. Patients were followed up for one year or until death. Operation was undertaken within 48 hours in 95.2% and after this in 4.8%. A significant increase in length of stay was found in patients operated on after 48 hours when compared with those in the earlier group (21.6 vs 32.5 days). No increase in hospital stay was found for lesser delays.
Gait abnormalities following rupture of the tendo Achillis
Authors: Costa M. L. , Kay D. , Donell S. T.
Published: July 2005

One of the factors that influence the outcome after rupture of the tendo Achillis is abnormality of gait. We prospectively assessed 14 patients and 15 normal control subjects using an in-shoe plantar pressure measurement system. There was a significant reduction in peak mean forefoot pressure in the early period of rehabilitation (p < 0.001). There was a concomitant rise in heel pressure on the injured side (p = 0.05). However, there was no difference in cadence, as determined by the duration of the terminal stance and pre-swing phases as a proportion of total stance. The forefoot pressure deficit in the group with tendon ruptures was smaller when assessed six months after the injury but was still significant (p = 0.029). Pedobarographic assessment confirms that there are marked abnormalities within the gait cycle. Rehabilitation programmes which address these abnormalities may improve outcome.
Sciatic nerve palsy after total hip replacement
Authors: Sosna A. , Pokorny D. , Jahoda D.
Published: July 2005

We report a case of sciatic nerve palsy following total hip replacement which has lead to a novel hypothesis to account for this complication.
Impact of the Clinical Pharmacist on Readmission in Patients with Acute Coronary Syndrome
Authors: O'Del Kate M , Kucukarslan Suzan N
Published: July 2005

BACKGROUND:

Previous studies have reported a positive impact of pharmacists on care of patients with chronic illnesses. The impact of the clinical pharmacist on hospital readmission in patients with acute coronary syndromes (ACS) has yet to be evaluated, as of this writing.

OBJECTIVE:

To evaluate the impact of the clinical pharmacist as a direct patient-care team member on cardiac-related readmission in patients admitted to the general cardiology unit with ACS.

METHODS:

A prospective, nonrandomized observational study compared patients who received standard practice care with patients admitted to a service with a clinical pharmacist to provide care at the bedside. Patients admitted to and discharged from the general cardiology unit for ACS were included. The primary endpoint of the study was cardiac-related readmission at 30 days following hospital discharge. Secondary endpoints included length of stay and medication utilization. Interventions provided by the clinical pharmacist in the study group were documented.

RESULTS:

Cardiac readmission at 30 days was similar between the groups (p = 0.59%). In the subset of patients with unstable angina, readmission in the study group was significantly lower than in the control group (1.3% vs 9.1%; p = 0.04%). Patients in both groups were similarly managed using drug therapy and invasive coronary interventions. The medical staff's rate of acceptance of recommendations provided by the pharmacist was 94.4%. The most common interventions were medication education and identification of indicated therapy.

CONCLUSIONS:

The addition of pharmacists did not decrease readmission in patients with ACS. The finding of significant reduction in readmission in the subset of patients with unstable angina should be considered “hypothesis generating” for future randomized studies to confirm the results.
Detection of Myelination Using a Novel Histological Probe
Authors: Xiang Zhongmin , Nesterov Evgueni E. , Skoch Jesse , Lin Tong , Hyman Bradley T. , Swager Timothy M. , Bacskai Brian J. , Reeves Steven A.
Published: July 2005

Current methods for myelin staining in tissue sections include both histological and immunohistochemical techniques. Fluorescence immunohistochemistry, which uses antibodies against myelin components such as myelin basic protein, is often used because of the convenience for multiple labeling. To facilitate studies on myelin, this paper describes a quick and easy method for direct myelin staining in rodent and human tissues using novel near-infrared myelin (NIM) dyes that are comparable to other well-characterized histochemical reagents. The near-infrared fluorescence spectra of these probes allow fluorescent staining of tissue sections in multiple channels using visible light fluorophores commonly used in immunocytochemistry. These dyes have been used successfully to detect normal myelin structure and myelin loss in a mouse model of demyelination disease.
Expression of Serum- and Glucocorticoid-Inducible Kinase Is Regulated in an Experience-Dependent Manner and Can Cause Dendrite Growth
Authors: David Samuel , Stegenga Susan L. , Hu Peter , Xiong Guoxiang , Kerr Elizabeth , Becker Katherine B. , Venkatapathy Sumathi , Warrington Janet A. , Kalb Robert G.
Published: July 2005

The interaction of an animal with its environment during a critical period in early postnatal life has lifelong effects on the structure and function of sensory and motor systems. To gain insight into the molecular mechanisms of experience-dependent development, we challenged young rats to adapt to a new environment that engenders novel motor behavior. Rats born in the gravitational field (1G) of the earth subsequently were reared for 2 weeks either in the absence of gravity (microgravity) or at 1G. A comparison of gene expression using microarrays led to the identification of a panel of differentially regulated transcripts. We report here that the abundance of serum- and glucocorticoid-inducible kinase (SGK) is increased in spinal cord tissue from animals reared in microgravity in comparison with 1G-reared controls. The induction of SGK expression also can be achieved by administration of glucocorticoids to animals at 1Gor neuronsin vitro. Expression of constitutively active SGK in neurons leads to the elaboration of neuronal dendrites and their branching. Glucocorticoids also lead to dendrite elaboration, and this effect can be abrogated by inhibiting SGK activity. Changes in the level of expression of SGK could be part of the mechanism for experience-dependent acquisition of mature neuronal properties.
Region-Specific Myelin Pathology in Mice Lacking the Golli Products of the Myelin Basic Protein Gene
Authors: Jacobs Erin C. , Pribyl Thomas M. , Kampf Kathy , Campagnoni Celia , Colwell Christopher S. , Reyes Samuel D. , Martin Melanie , Handley Vance , Hiltner Timothy D. , Readhead Carol , Jacobs Russell E. , Messing Albee , Fisher Robin S. , Campagnoni Anthony T.
Published: July 2005

The myelin basic protein (MBP) gene encodes two families of proteins, the classic MBP constituents of myelin and the golli-MBPs, the function of which is less well understood. In this study, targeted ablation of the golli-MBPs, but not the classic MBPs, resulted in a distinct phenotype unlike that of knock-outs (KOs) of the classic MBPs or other myelin proteins. Although the golli KO animals did not display an overt dysmyelinating phenotype, they did exhibit delayed and/or hypomyelination in selected areas of the brain, such as the visual cortex and the optic nerve, as determined by Northern and Western blots and immunohistochemical analysis with myelin protein markers. Hypomyelination in some areas, such as the visual cortex, persisted into adulthood. Ultrastructural analysis of the KOs confirmed both the delay and hypomyelination and revealed abnormalities in myelin structure and in some oligodendrocytes. Abnormal visual-evoked potentials indicated that the hypomyelination in the visual cortex had functional consequences in the golli KO brain. Evidence that the abnormal myelination in these animals was a consequence of intrinsic problems with the oligodendrocyte was indicated by an impaired ability of oligodendrocytes to form myelin sheets in culture and by the presence of abnormal Ca2+transients in purified cortical oligodendrocytes studiedin vitro. The Ca2+results reported in this study complement previous results implicating golli proteins in modulating intracellular signaling in T-cells. Together, all these findings suggest a role for golli proteins in oligodendrocyte differentiation, migration, and/or myelin elaboration in the brain.
Differential Regulation of CaV2.1 Channels by Calcium-Binding Protein 1 and Visinin-Like Protein-2 Requires N-Terminal Myristoylation
Authors: Few Alexandra P. , Lautermilch Nathan J. , Westenbroek Ruth E. , Scheuer Todd , Catterall William A.
Published: July 2005

P/Q-type Ca2+currents through presynaptic CaV2.1 channels initiate neurotransmitter release, and differential modulation of these channels by neuronal calcium-binding proteins (nCaBPs) may contribute to synaptic plasticity. The nCaBPs calcium-binding protein 1 (CaBP1) and visinin-like protein-2 (VILIP-2) differ from calmodulin (CaM) in that they have an N-terminal myristoyl moiety and one EF-hand that is inactive in binding Ca2+. To determine whether myristoylation contributes to their distinctive modulatory properties, we studied the regulation of CaV2.1 channels by the myristoyl-deficient mutants CaBP1/G2A and VILIP-2/G2A. CaBP1 positively shifts the voltage dependence of CaV2.1 activation, accelerates inactivation, and prevents paired-pulse facilitation in a Ca2+-independent manner. Block of myristoylation abolished these effects, leaving regulation that is similar to endogenous CaM. CaBP1/G2A binds to CaV2.1 with reduced stability, butin situprotein cross-linking and immunocytochemical studies revealed that it binds CaV2.1in situand is localized to the plasma membrane by coexpression with CaV2.1, indicating that it binds effectively in intact cells. In contrast to CaBP1, coexpression of VILIP-2 slows inactivation in a Ca2+-independent manner, but this effect also requires myristoylation. These results suggest a model in which nonmyristoylated CaBP1 and VILIP-2 bind to CaV2.1 channels and regulate them like CaM, whereas myristoylation allows differential, Ca2+-independent regulation by the inactive EF-hands of CaBP1 and VILIP-2, which differ in their positions in the protein structure. Differential, myristoylation-dependent regulation of presynaptic Ca2+channels by nCaBPs may provide a flexible mechanism for diverse forms of short-term synaptic plasticity.
Chromogranin A Deficiency in Transgenic Mice Leads to Aberrant Chromaffin Granule Biogenesis
Authors: Kim Taeyoon , Zhang Chun-fa , Sun Ziqing , Wu Heling , Loh Y. Peng
Published: July 2005

The biogenesis of dense-core secretory granules (DCGs), organelles responsible for the storage and secretion of neurotransmitters and neuropeptides in chromaffin cells, is poorly understood. Chromogranin A (CgA), which binds catecholamines for storage in the lumen of chromaffin granules, has been shown to be involved in DCG biogenesis in neuroendocrine PC12 cells. Here, we report that downregulation of CgA expressionin vivoby expressing antisense RNA against CgA in transgenic mice led to a significant reduction in DCG formation in adrenal chromaffin cells. The number of DCGs formed in CgA antisense transgenic mice was directly correlated with the amount of CgA present in adrenal medulla. In addition, DCGs showed an increase in size, with enlargement in the volume around the dense core, a phenomenon that occurs to maintain constant “free” catecholamine concentration in the lumen of these granules. The extent of DCG swelling was inversely correlated with the number of DCGs formed, as well as the amount of CgA present in the adrenal glands of CgA antisense transgenic mice. These data indicate an essential role of CgA in regulating chromaffin DCG biogenesis and catecholamine storagein vivo.
Functional Recovery in Traumatic Spinal Cord Injury after Transplantation of Multineurotrophin-Expressing Glial-Restricted Precursor Cells
Authors: Cao Qilin , Xu Xiao-Ming , DeVries William H. , Enzmann Gaby U. , Ping Peipei , Tsoulfas Pantelis , Wood Patrick M. , Bunge Mary Bartlett , Whittemore Scott R.
Published: July 2005

Demyelination contributes to the physiological and behavioral deficits after contusive spinal cord injury (SCI). Therefore, remyelination may be an important strategy to facilitate repair after SCI. We show here that rat embryonic day 14 spinal cord-derived glial-restricted precursor cells (GRPs), which differentiate into both oligodendrocytes and astrocytes, formed normal-appearing central myelin around axons of cultured DRG neurons and had enhanced proliferation and survival in the presence of neurotrophin 3 (NT3) and brain-derived neurotrophin factor (BDNF). We infected GRPs with retroviruses expressing the multineurotrophin D15A (with both BDNF and NT3 activities) and then transplanted them into the contused adult thoracic spinal cord at 9 d after injury. Expression of D15A in the injured spinal cord is five times higher in animals receiving D15A-GRP grafts than ones receiving enhanced green fluorescent protein (EGFP)-GRP or DMEM grafts. Six weeks after transplantation, the grafted GRPs differentiated into mature oligodendrocytes expressing both myelin basic protein (MBP) and adenomatus polyposis coli (APC). Ultrastructural analysis showed that the grafted GRPs formed morphologically normal-appearing myelin sheaths around the axons in the ventrolateral funiculus (VLF) of spinal cord. Expression of D15A significantly increased the percentage of APC+oligodendrocytes of grafted GRPs (15-30%). Most importantly, 8 of 12 rats receiving grafts of D15A-GRPs recovered transcranial magnetic motor-evoked potential responses, indicating that conduction through the demyelinated VLF axons was restored. Such electrophysiological recovery was not observed in rats receiving grafts of EGFP-GRPs, D15A-NIH3T3 cells, or an injection of an adenovirus expressing D15A. Recovery of hindlimb locomotor function was also significantly enhanced only in the D15A-GRP-grafted animals at 4 and 5 weeks after transplantation. Therefore, combined treatment with neurotrophins and GRP grafts can facilitate functional recovery after traumatic SCI and may prove to be a useful therapeutic strategy to repair the injured spinal cord.
Interaction via a Key Tryptophan in the I-II Linker of N-Type Calcium Channels Is Required for β1 But Not for Palmitoylated β2, Implicating an Additional Binding Site in the Regulation of Channel Voltage-Dependent Properties
Authors: Leroy Jérôme , Richards Mark S. , Butcher Adrian J. , Nieto-Rostro Manuela , Pratt Wendy S. , Davies Anthony , Dolphin Annette C.
Published: July 2005

The CaVβ subunits of voltage-gated calcium channels regulate these channels in several ways. Here we investigate the role of these auxiliary subunits in the expression of functional N-type channels at the plasma membrane and in the modulation by G-protein-coupled receptors of this neuronal channel. To do so, we mutated tryptophan 391 to an alanine within the α-interacting domain (AID) in the I-II linker of CaV2.2. We showed that the mutation W391 virtually abolishes the binding of CaVβ1b and CaVβ2a to the CaV2.2 I-II linker and strongly reduced current density and cell surface expression of both CaV2.2/α2δ-2/β1b and/β2a channels. When associated with CaVβ1b, the W391A mutation also prevented the CaVβ1b-mediated hyperpolarization of CaV2.2 channel activation and steady-state inactivation. However, the mutated CaV2.2W391A/β1b channels were still inhibited to a similar extent by activation of the D2dopamine receptor with the agonist quinpirole. Nevertheless, key hallmarks of G-protein modulation of N-type currents, such as slowed activation kinetics and prepulse facilitation, were not observed for the mutated channel. In contrast, CaVβ2a was still able to completely modulate the biophysical properties of CaV2.2W391A channel and allow voltage-dependent G-protein modulation of CaV2.2W391A. Additional data suggest that the concentration of CaVβ2a in the proximity of the channel is enhanced independently of its binding to the AID by its palmitoylation. This is essentially sufficient for all of the functional effects of CaVβ2a, which may occur via a second lower-affinity binding site, except trafficking the channel to the plasma membrane, which requires interaction with the AID region.
Pax6 Is Required for Making Specific Subpopulations of Granule and Periglomerular Neurons in the Olfactory Bulb
Authors: Kohwi Minoree , Osumi Noriko , Rubenstein John L. R. , Alvarez-Buylla Arturo
Published: July 2005

The subventricular zone (SVZ) produces different subclasses of olfactory bulb (OB) interneurons throughout life. Little is known about the molecular mechanisms controlling the production of different types of interneurons. Here we show that most proliferating adult SVZ progenitors express the transcription factor Pax6, but only a small subpopulation of migrating neuroblasts and new OB interneurons derived from these progenitors retains Pax6 expression. To elucidate the cell-autonomous role of Pax6 in OB neurogenesis, we transplanted green fluorescent protein-expressing embryonic forebrain progenitors of the dorsal lateral ganglionic eminence from Pax6 mutantSmall Eye(Pax6Sey/Sey) mice into the SVZ of adult wild-type mice. Pax6Sey/Seyprogenitors produce neuroblasts capable of migrating into the OB but fail to generate dopaminergic periglomerular and superficial granule cells. Interestingly, superficial granule neurons also express mRNA for tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis. Our data show that SVZ neuroblasts are heterogeneous and that Pax6 is required in a cell-autonomous manner for the production of cells in the dopaminergic lineage.
Homer2 Is Necessary for EtOH-Induced Neuroplasticity
Authors: Szumlinski Karen K. , Lominac Kevin D. , Oleson Erik B. , Walker Jennifer K. , Mason Ashley , Dehoff Marlin H. , Klugman Matthias , Cagle Stephanie , Welt Kristine , During Matthew , Worley Paul F. , Middaugh Lawrence D. , Kalivas Peter W.
Published: July 2005

Homer proteins are integral to the assembly of proteins regulating glutamate signaling and synaptic plasticity. ConstitutiveHomer2gene deletion [knock-out (KO)] and rescue with adeno-associated viral (AAV) transfection ofHomer2bwas used to demonstrate the importance of Homer proteins in neuroplasticity produced by repeated ethanol (EtOH) administration.Homer2KO mice avoided drinking high concentrations of EtOH and did not develop place preference or locomotor sensitization after repeated EtOH administration. The deficient behavioral plasticity to EtOH afterHomer2deletion was paralleled by a lack of augmentation in the rise in extracellular dopamine and glutamate elicited by repeated EtOH injections. The genotypic differences in EtOH-induced change in behavior and neurochemistry were essentially reversed by AAV-mediated transfection ofHomer2binto accumbens cells including, differences in EtOH preference, locomotor sensitization, and EtOH-induced elevations in extracellular glutamate and dopamine. These data demonstrate a necessary and active role for accumbens Homer2 expression in regulating EtOH-induced behavioral and cellular neuroplasticity.
Pattern-Dependent Role of NMDA Receptors in Action Potential Generation: Consequences on Extracellular Signal-Regulated Kinase Activation
Authors: Zhao Meilan , Adams J. Paige , Dudek Serena M.
Published: July 2005

Synaptic long-term potentiation is maintained through gene transcription, but how the nucleus is recruited remains controversial. Activation of extracellular signal-regulated kinases (ERKs) 1 and 2 with synaptic stimulation has been shown to require NMDA receptors (NMDARs), yet stimulation intensities sufficient to recruit action potentials (APs) also appear to be required. This has led us to ask the question of whether NMDARs are necessary for AP generation as they relate to ERK activation. To test this, we examined the effects of NMDAR blockade on APs induced with synaptic stimulation using whole-cell current-clamp recordings from CA1 pyramidal cells in hippocampal slices. NMDAR antagonists were found to potently inhibit APs generated with 5 and 100 Hz synaptic stimulation. Blockade of APs and ERK activation could be overcome with the addition of the GABAAantagonist bicuculline, indicating that APs are sufficient to activate signals such as ERK in the nucleus and throughout the neuron in the continued presence of NMDAR antagonists. Interestingly, no effects of the NMDAR antagonists were observed when theta-burst stimulation (TBS) was used. This resistance to the antagonists is conferred by temporal summation during the bursts. These results clarify findings from a previous study showing that ERK activation induced with TBS is resistant to 2-amino-5-phosphonovalerate, in contrast to that induced with 5 or 100 Hz stimulation, which is sensitive. By showing that NMDAR blockade inhibits AP generation, we demonstrate that a major role that NMDARs play in cell-wide and nuclear ERK activation is through their contribution to action potential generation.
Integrin-Linked Kinase Deletion from Mouse Cortex Results in Cortical Lamination Defects Resembling Cobblestone Lissencephaly
Authors: Niewmierzycka Agnieszka , Mills Julia , St-Arnaud Rene , Dedhar Shoukat , Reichardt Louis F.
Published: July 2005

Integrin-linked kinase (Ilk) is a scaffold and kinase that links integrin receptors to the actin cytoskeleton and to signaling pathways involved in cell adhesion, migration, and extracellular matrix deposition. Targeted deletion ofIlkfrom embryonic mouse dorsal forebrain neuroepithelium results in severe cortical lamination defects resembling cobblestone (type II) lissencephaly. Defects in adult mutants include neuronal invasion of the marginal zone, downward displacement of marginal zone components, fusion of the cerebral hemispheres, and scalloping of the dentate gyrus. These lesions are associated with abundant astrogliosis and widespread fragmentation of the basal lamina at the cortical surface. During cortical development, neuronal ectopias are associated with severe disorganization of radial glial processes and displacement of Cajal-Retzius cells. Lesions are not seen whenIlkis specifically deleted from embryonic neurons. Interestingly, targetedIlkdeletion has no effect on proliferation or survival of cortical cells or on phosphorylation of two Ilk substrates, Pkb/Akt and Gsk-3β, suggesting that Ilk does not regulate cortical lamination via these enzymes. Instead, Ilk actsin vivoas a major intracellular mediator of integrin-dependent basal lamina formation. This study demonstrates a critical role for Ilk in cortical lamination and suggests that Ilk-associated pathways are involved in the pathogenesis of cobblestone lissencephalies.
Neurofilament Polymer Transport in Axons
Authors: Yan Yanping , Brown Anthony
Published: July 2005

Neurofilament proteins are known to be transported along axons by slow axonal transport, but the form in which they move is controversial. In previous studies on cultured rat sympathetic neurons, we found that green fluorescent protein-tagged neurofilament proteins move predominantly in the form of filamentous structures, and we proposed that these structures are single-neurofilament polymers. In the present study, we have tested this hypothesis by using a rapid perfusion technique to capture these structures as they move through naturally occurring gaps in the axonal neurofilament array. Because the gaps lack neurofilaments, they permit unambiguous identification of the captured structure. Using quantitative immunofluorescence microscopy and correlative light and electron microscopy, we show that the captured structures are single continuous neurofilament polymers. Thus, neurofilament polymers are one of the cargo structures of slow axonal transport.
Temporal and spatial associations of oestrogen receptor alpha and progesterone receptor in the endometrium of cyclic and early pregnant mares
Authors: Hartt L S , Carling S J , Joyce M M , Johnson G A , Vanderwall D K , Ott T L
Published: July 2005

Uterine function is primarily controlled by the combined actions of oestrogen and progesterone working through their cognate nuclear receptors. The mechanism of establishment of pregnancy in the mare is of interest because it involves prolonged pre-attachment and conceptus migration phases, and both invasive and non-invasive placental cell types, and as such has been an important comparative model. This study characterised regulation of oestrogen (ER) and progesterone (PR) receptors in the endometrium of the mare during the oestrous cycle and early pregnancy. Endometrial tissues collected during the oestrous cycle and early pregnancy were analysed for steady-state levels of ER and PR mRNA and protein. Steady-state levels of ER and PR mRNA were highest on days 0, 17 and 20 in cyclic mares and lowest on days 11 and 14. A day-by-status interaction was detected, indicating that day 17 and day 20 pregnant mares exhibited low levels of ER and PR compared with the corresponding days of the oestrous cycle. In situ hybridisation analyses showed receptor mRNA localisation primarily in the luminal epithelium (LE), glandular epithelium (GE) and stroma around oestrus. During dioestrus and early pregnancy, receptors were not detected in the LE, and were lower in the stroma and deeper GE. Changes in hybridisation intensity in these cell types were consistent with changes in mRNA levels detected by slot-blot hybridisation. ER and PR proteins were detected in the nuclei of LE, GE and stromal cells. Consistent with results from in situ hybridisation, levels of ER and PR immunoreactivity were higher around oestrus, declined to low levels during dioestrus and remained low during early pregnancy. Results described here for temporal and spatial changes in steroid receptor gene expression in mares show the greatest similarities with those described for cattle and sheep.
Recombination in men with Klinefelter syndrome
Authors: Gonsalves Joanna , Turek Paul J , Schlegel Peter N , Hopps Carin V , Weier Jingly Fung , Pera Renee A Reijo
Published: July 2005

Klinefelter syndrome (KS: 47,XXY), occurs in one in 1000 male births. Men with KS are infertile and have higher rates of aneuploidies in sperm compared with normal fertile men. In the course of analyzing recombination in a population of infertile men, we observed that four men in our study presented with KS. We examined whether these men differed in recombination parameters among themselves and relative to normal men. Even though the number of men with KS analyzed was small, we observed remarkable variation in spermatogenesis. In spite of the fact that the men had the same genetic cause for infertility, two of four KS patients had few or no spermatogenic cells that progressed through meiosis to the pachytene stage, whereas the other two men produced abundant pachytene cells that had recombination frequencies comparable with those of fertile men, although one had a significant reduction in fidelity of synapsis. Moreover, regardless of histological appearance, examination of outcomes of assisted reproduction indicated that sperm were extracted from testis biopsies in all four cases, and when used in assisted reproductive practices chromosomally normal babies were born. These results reinforce that: (i) men with the same underlying genetic cause for infertility do not present with uniform pathology, (ii) the checkpoint machinery that might arrest spermatogenesis in the face of chromosomal abnormalities does not prevent pockets of complete spermatogenesis in men with KS, and (iii) aneuploidy, in some cases, is compatible with birth of a chromosomally normal child, suggesting that sperm produced from a background of aneuploidy can be normal in men with KS.
Impact of various endocrine and paracrine factors on in vitro culture of preantral follicles in rodents
Authors: Demeestere I , Centner J , Gervy C , Englert Y , Delbaere A
Published: July 2005

Folliculogenesis is a complex process regulated by various paracrine and autocrine factors. In vitro growth systems of primordial and preantral follicles have been developed for future use of immature oocytes, as sources of fertilizable oocytes and for studying follicular growth and oocyte maturation mechanisms. Rodents were often chosen for in vitro follicular culture research and a lot of factors implicated in folliculogenesis have been identified using this model. To date, the mouse is the only species in which the whole process of follicular growth, oocyte maturation, fertilization and embryo transfer into recipient females was successfully performed. However, the efficiency of in vitro culture systems must still be considerably improved. Within the follicle, numerous events affect cell proliferation and the acquisition of oocyte developmental competency in vitro, including interactions between the follicular cells and the oocyte, and the composition of the culture medium. Effects of the acting factors depend on the stage of follicle development, the culture system used and the species. This paper reviews the action of endocrine, paracrine factors and other components of culture medium on in vitro growth of preantral follicles in rodents.
Expression of IGF-II mRNA-binding proteins (IMPs) in gonads and testicular cancer
Authors: Hammer Niels A , Hansen Thomas v O , Byskov Anne Grete , Rajpert-De Meyts Eva , Grøndahl Marie Louise , Bredkjær Helle E , Wewer Ulla M , Christiansen Jan , Nielsen Finn C
Published: July 2005

Insulin-like growth factor-II mRNA-binding proteins 1, 2 and 3 (IMP1, IMP2 and IMP3) belong to a family of RNA-binding proteins implicated in mRNA localization, turnover and translational control. We examined their expression pattern during development of murine and human testis and ovaries. In the mouse, IMPs were expressed in male and female gonadal cells at embryonic day 12.5 (E12.5). From E16.5, IMP1 and IMP3 became restricted to the developing germ cells, whereas IMP2 expression persisted in the interstitial cells. In mature mouse and human ovaries, IMP1, IMP2 and IMP3 were detected in resting and growing oocytes and in the granulosa cells. In testis, IMP1 and IMP3 were found mainly in the spermatogonia, whereas IMP2 was expressed in the immature Leydig cells. Moreover, all three IMPs were detected in human semen. The developmental expression pattern of IMP1 and IMP3 in the human testis prompted us to examine their possible involvement in testicular neoplasia. IMPs were detected primarily in germ-cell neoplasms, including preinvasive testicular carcinomain situ, classical and spermatocytic seminoma, and nonseminomas, with particularly high expression in undifferentiated embryonal carcinoma. The relative expression of IMP1, IMP2 and IMP3 varied among tumor types and only IMP1 was detected in all carcinomain situcells. Thus IMPs, and in particular IMP1, may be useful auxiliary markers of testicular neoplasia.
Phospholipase Cζ, the trigger of egg activation in mammals, is present in a non-mammalian species
Authors: Coward K , Ponting C P , Chang H-Y , Hibbitt O , Savolainen P , Jones K T , Parrington J
Published: July 2005

The activation of the egg to begin development into an embryo is triggered by a sperm-induced increase in intracellular egg Ca2+. There has been much controversy about how the sperm induces this fundamental developmental event, but recent studies suggest that, in mammals, egg activation is triggered by a testis-specific phospholipase C: PLCζ. Since the discovery of PLCζ, it has been unclear whether its role in triggering egg activation is common to all vertebrates, or is confined to mammals. Here, we demonstrate for the first time that PLCζ is present in a non-mammalian vertebrate. Using genomic and cDNA databases, we have identified the cDNA encoding a PLCζ orthologue in the domestic chicken that, like the mammalian isoforms, is a testis-specific gene. The chicken PLCζ cDNA is 2152 bp in size and encodes an open reading frame of 639 amino acids. When injected into mouse oocytes, chicken PLCζ cRNA triggers Ca2+oscillations, indicating that it has functional properties similar to those of mammalian PLCζ. Our findings suggest that PLCζ may have a universal role in triggering egg activation in vertebrates.
Ruthenium Complexes Bearing N-Heterocyclic Carbene (NHC) Ligands
Authors: Dragutan Valerian , Dragutan Ileana , Demonceau Albert
Published: July 2005

The vast family of ruthenium complexes with nucleophilic N-heterocyclic carbene (NHC) ligands is selectively discussed as an improved alternative to their parent diphosphane ruthenium counterparts previously applied in olefin metathesis reactions. The survey covers work done to-date
on the ruthenium alkylidene, vinylidene, allenylidene and indenylidene complexes bearing imidazolin-2-ylidene and dihydroimidazolin-2-ylidene carbenes, as well as a number of immobilised ruthenium complexes having these types of ligands. Examples of chiral compounds complete the spectrum of
NHC ruthenium complexes. Synthetic methods, catalytic properties and application profile in ring-closing metathesis, cross metathesis, ring-opening metathesis and metathesis polymerisation are highlighted.
The Thermodynamic Properties of Platinum
Authors: Arblaster J. W.
Published: July 2005

The thermodynamic properties of platinum were reviewed here by the author in 1994. However, the use of superior values for the enthalpy of liquid platinum have resulted in a major revision of the thermodynamic values for the liquid phase. One consequence of the revision is that the
boiling point at one atmosphere pressure is altered from 4125 K, as calculated in the 1994 paper, to 4149 K. Previously accepted values for solid platinum are not altered, and there are only very minor changes to the gaseous phase values as a result of using a new atomic weight for platinum
and the CODATA 2002 recommended values of the fundamental constants.
Diesel Engines: Design and Emissions
Authors: Pignon John
Published: July 2005

Diesel engines have major roles in automotive and stationary applications, both large (heavy duty) and small (light duty). Diesel engines are energy efficient, but their NOx and particulate emissions present major obstacles to engine development. This selective review of the course
"Diesel Particulates and NOx Emissions" reports the latest developments taking place in diesel technology: engine design, fuel injection systems, fuel, lubricants, turbochargers, aftertreatment, emissions and health effects, that impact on particulate and NOx emissions. The course is run by
the University of Leeds, Energy and Resources Research Institute.
Cystatin C expression is associated with granule cell dispersion in epilepsy
Authors: Pirttilä Terhi J. , Manninen Anni , Jutila Leena , Nissinen Jari , Kälviäinen Reetta , Vapalahti Matti , Immonen Arto , Paljärvi Leo , Karkola Kari , Alafuzoff Irina , Mervaala Esa , Pitkänen Asla
Published: July 2005

Human temporal lobe epilepsy (TLE) is associated with cellular alterations (eg, hilar cell death, neurogenesis, and granule cell dispersion) in the dentate gyrus but their underlying molecular mechanism are not known. We previously demonstrated increased expression of cystatin C, a protease inhibitor linked to both neurodegeneration and neurogenesis, during epileptogenesis in the rat hippocampus. Here, we investigated cystatin C expression in the dentate gyrus in chronic epilepsy and its association with neuronal loss and neurogenesis. In both rats with epilepsy and human patients with TLE, cystatin C expression was increased in glial cells in the molecular layer of the dentate gyrus, being most prominent in cases with granule cell dispersion. In patients with TLE, high cystatin C expression associated with greater numbers of polysialylated neural cell adhesion molecule–positive newborn cells in the molecular layer, although the overall number was decreased, indicating that the newborn cells migrate to abnormal locations in the epileptic dentate gyrus. These data thus demonstrate that cystatin C expression is altered during the chronic phase of epilepsy and suggest that cystatin C plays a role in network reorganization in the epileptic dentate gyrus, especially in granule cell dispersion and guidance of migrating newborn granule cells. Ann Neurol 2005;58:211–223
Complement inhibition abrogates nerve terminal injury in Miller Fisher syndrome
Authors: Halstead Susan K. , Humphreys Peter D. , Goodfellow John A. , Wagner Eric R. , Smith Richard A. G. , Willison Hugh J.
Published: July 2005

A large body of clinical and experimental data indicate that complement activation is an important mechanism for neuronal and glial injury in Guillain–Barré syndromes. Inhibition of complement activation therefore might be expected to limit the progression of the disease. Using in vitro and in vivo models of the Guillain–Barré syndrome variant, Miller Fisher syndrome, we have shown previously that anti‐GQ1b ganglioside antibodies target the presynaptic motor nerve terminal axon and surrounding perisynaptic Schwann cells, thereby mediating destructive injury through deposition of membrane attack complex. Here, we have used this model to investigate the effects of a novel therapeutic inhibitor of complement activation, APT070 (Mirococept), both in vitro and in vivo. In these models, APT070 completely prevents membrane attack complex formation, and thereby has a major neuroprotective effect at the nerve terminal, as assessed by immunohistology of perisynaptic Schwann cell and axonal integrity. These data provide a rationale for considering clinical trials of APT070 in Guillain–Barré syndrome, its variant forms, and other complement dependent neuromuscular disorders. Ann Neurol 2005;58:203–210