Central neurocytoma: case report of an 81-year-old and histopathologic findings

Central Neurocytomas are rare and usually benign tumors found primarily in the lateral ventricles of the brain. Central Neurocytomas are composed of uniform round cells exhibiting neuronal differentiation and are found almost exclusively in young adults between 15 and 60 years of age. The authors report the case of an 81-year-old man with a history of severe psychosis and depression, who presented with progressive confusion and ataxia likely unrelated to a central neurocytoma of his right lateral ventricle. The patient underwent a stereotactic biopsy of the lesion, followed by Gamma Knife radiosurgery. Histopathology showed immunohistological staining for synaptophysin, neuron specific enolase (NSE) and neuronal nuclear antigen (NeuN). A review of published literature on central neurocytomas revealed that this tumor occurs most frequently in young adults with a median age between 25 and 30 years. This pathology has never been reported in patients over the age of 80. Gamma Knife radiosurgery was successful in decreasing the tumor volume by 20% at the four month follow-up, but the fact that the patient died of unrelated occurrences in the elderly cannot be ruled out. Patients with central neurocytomas commonly present with obstructive hydrocephalus and immediate treatment may be necessary to tide over urgent situations.

An IPM Program for Managing Fungal Leaf Blight Diseases of Carrot in New York

Fungal leaf blight diseases caused by Cercospora carotae and Alternaria dauci occur annually on processing carrot in New York, with growers applying up to eight fungicide sprays to manage these diseases. An integrated pest management (IPM) program involving the use of a 25% disease incidence threshold to prompt the first fungicide application and timing subsequent sprays by monitoring for increases in disease severity and weather forecasts in conjunction with a 10- to 14-day spray interval was evaluated in grower fields in 1997 and 1998. The IPM plots, compared with the grower plots, required two to six fewer fungicide applications but showed no yield reduction. From 1999 to 2004, the IPM program was validated and the effect of crop rotation and carrot cultivar susceptibility also were assessed. Carrot plants growing in fields with 2-year or longer crop rotation intervals reached the 25% disease incidence threshold later in the season and required fewer fungicide applications. The less-susceptible carrot cultivars also reached the 25% disease incidence threshold later, required fewer fungicide applications, and were less severely diseased than more susceptible cultivars. Validation of the IPM program in New York showed that both fungal leaf blights can be managed effectively using a 25% incidence threshold to prompt the first fungicide spray and making the subsequent fungicide applications based on increases in disease severity, weather forecasts, and a 10- to 14-day spray interval.

Teriparatide in postmenopausal women with osteoporosis and mild or moderate renal impairment

INTRODUCTION

The prevalence of both osteoporosis and renal impairment increases with age.

METHODS

Using data from the Fracture Prevention Trial, the safety and efficacy of teriparatide [rhPTH(1-34)] in postmenopausal women with osteoporosis and renal impairment were explored. Patients were required to have serum creatinine concentrations < or =2.0 mg/dl and normal serum parathyroid hormone (PTH) concentrations and were randomized to receive daily subcutaneous injections of placebo or teriparatide 20 or 40 mcg/day. Glomerular filtration rate (GFR) was estimated using the Cockcroft-Gault equation. Patients were defined from baseline assessments to have normal (GFR > or =80 ml/min), mildly impaired (GFR 50-79 ml/min), or moderately impaired (GFR 30-49 ml/min) renal function for bone mineral density (BMD) and amino-terminal extension peptide of procollagen type 1 (PINP) analyses, and normal (GFR > or =80 ml/min) or impaired (GFR <80 ml/min) renal function for fracture analyses.

RESULTS AND CONCLUSIONS

Compared with patients with normal renal function, patients with renal impairment were older, shorter, weighed less, had been postmenopausal longer, and had lower baseline lumbar spine and femoral neck BMD. Compared with placebo, teriparatide significantly increased PINP and lumbar spine and femoral neck BMD within each renal function subgroup, and there was no evidence that these increases were altered by renal insufficiency (each treatment-by-subgroup interaction p>0.05). Similarly, teriparatide-mediated vertebral and nonvertebral fracture risk reductions were similar and did not differ significantly between patients with normal or impaired renal function (treatment-by-subgroup interactions p>0.05). The incidences of treatment-emergent and renal-related adverse events were consistent across treatment assignment in the normal, mildly impaired, and moderately impaired renal function subgroups. Teriparatide induced changes in mean GFR were unaffected by baseline renal function (treatment-by-renal function interaction p>0.05 for normal, mildly impaired, or moderately impaired subgroups). Patients in all renal function categories treated with teriparatide 20 or 40 mcg had an increased incidence of 4-6-h postdose serum calcium >10.6 mg/dl (the upper limit of normal) versus placebo; however, teriparatide 20 mcg/day was not associated with significantly increased incidence of 4-6-h postdose serum calcium >11 mg/dl in any renal function category. Teriparatide therapy was associated with increased incidence of elevated uric acid, with the incidences being highest in patients with moderately impaired renal function and in those receiving teriparatide 40 mcg/day. Even so, adverse event data did not suggest an increased incidence of gout or arthralgia or of nephrolithiasis events in teriparatide-treated patients with normal, mild, or moderate renal impairment.

Severity of vertebral fracture reflects deterioration of bone microarchitecture

INTRODUCTION

Bone microarchitecture, a component of bone strength, is generally measured on transiliac bone biopsy samples. The objective of this study was to determine whether assessment of four grades of vertebral fracture severity could serve as a noninvasive surrogate marker for trabecular bone volume and microarchitecture.

METHODS

Baseline vertebral fracture severity was determined by semiquantitative assessment of spine radiographs from 190 postmenopausal women with osteoporosis. Bone-structure indices were obtained by 2D histomorphometry and 3D microcomputed tomography (CT) analyses. Significance of differences was determined after adjusting for age, height, and lumbar spine bone mineral density.

RESULTS

There were significant (P < 0.05) trends in decreasing bone volume, trabecular number, and connectivity, and increasing trabecular separation with greater vertebral fracture severity. Histomorphometric bone volume was 25 and 36% lower (P < 0.05) in women with moderate and severe fractures than in women with no fractures, respectively. Compared with women without fractures, women with mild, moderate, and severe fractures had lower (P < 0.05) microCT bone volume (23, 30, and 51%, respectively).

CONCLUSIONS

Microarchitectural deterioration was progressively worse in women with increasing severity of vertebral fractures. We conclude that assessment of vertebral fracture severity is an important clinical tool to evaluate the severity of postmenopausal osteoporosis.

Formation of colloidal suspension of hydrophobic compounds with an amphiphilic self-assembling peptide

The amphiphilic self-assembling peptide EAK16-II was found to be able to stabilize hydrophobic compounds in aqueous solution. Micro/nanocrystals of a hydrophobic compound, pyrene, and a hydrophobic anticancer agent, ellipticine, were stabilized by EAK16-II to form colloidal suspensions in water. Initial evidence of the association between EAK16-II and hydrophobic compounds was the observation of a clouding phenomenon and a difference in fluorescence spectra of the solution. A further investigation on the interaction between EAK16-II and pyrene was carried out using fluorescence spectroscopy and scanning electron microscopy (SEM). It was found that the pyrene-peptide complex formation required mechanical stirring, and the freshly prepared peptide solution (containing peptide monomers and/or peptide protofibrils) was more effective at stabilizing pyrene than the mature fibrils in aged peptide solutions. The time duration over which the complex formed was about 22 h. The data on the complexation of pyrene and EAK16-II at various concentrations suggested that the maximum amount of stabilized pyrene was concentration dependent. SEM images showed that peptide concentration did not significantly affect the size of the complexes/suspensions but altered the structures of the peptide coating on the surface of the complex. Atomic force microscopy (AFM) was conducted to study the interaction of EAK16-II with a model hydrophobic surface, which provided some detailed information of how peptide adsorbed onto the hydrophobic compounds and stabilize them. This study shows the potential of self-assembling peptides for encapsulation of hydrophobic compounds.

Response rate of bone mineral density to teriparatide in postmenopausal women with osteoporosis

PURPOSE

It is desirable for clinicians to know what bone mineral density (BMD) response they can expect in women treated with osteoporosis therapies. The focus of this analysis was to determine what percentage of women attained a lumbar spine BMD response to teriparatide that equaled or exceeded the least significant change (LSC) value of 3%.

METHODS

Data from three clinical trials involving postmenopausal women with osteoporosis were examined. The Fracture Prevention Trial was a double-blinded, placebo-controlled clinical trial examining the safety and efficacy of teriparatide 20 and 40 microg/day. The other two trials were double-blinded, head-to-head comparisons of alendronate 10 mg/day and teriparatide 20 or 40 microg/day, respectively. Only treatment-compliant women who had lumbar spine BMD measurements at all specified time points in these trials were included. For reference, we also examined the percentage of women with lumbar spine BMD responses to alendronate. Hip BMD responses that equaled or exceeded 3% were also examined.

RESULTS

According to the LSC criteria, 91% of the teriparatide 20 microg/day group and 94% of the teriparatide 40 microg/day group were lumbar spine BMD responders at 18 months in the Fracture Prevention Trial. In the teriparatide 20 microg/alendronate head-to-head trial, 94% of women receiving teriparatide had a lumbar spine BMD response that equaled or exceeded the 3% criterion at 18 months compared to 75% of those receiving alendronate 10 mg/day (p < 0.01). In the teriparatide 40 microg/day group of the other head-to-head trial, 92% of women achieved the 3% criterion for the lumbar spine at 12 months compared to 69% of those receiving alendronate 10 mg/day (p < 0.01). The median 3-month change in amino-terminal extension peptide of procollagen type 1 [PINP] in women who had a lumbar spine BMD response to teriparatide at 18 months was larger than in women who did not have a lumbar spine BMD response. However, the median 3-month PINP change in lumbar spine BMD nonresponders still exceeded the LSC value of 10 microg/L. Although the percentage of teriparatide-treated women with a hip BMD response that met the 3% criterion was significantly greater than for placebo, there was no significant difference between the percentage of teriparatide 20 microg/day and alendronate 10 mg/day responders in the comparison trial. The baseline characteristics of teriparatide lumbar spine responders and nonresponders were similar.

CONCLUSION

This analysis demonstrates that the vast majority of treatment-compliant postmenopausal women with osteoporosis and minimal prior bisphosphonate exposure have a lumbar spine BMD response to teriparatide that meets or exceeds the LSC. The characteristics of teriparatide responders and nonresponders were not significantly different; thus, we were unable to discern any characteristics that could be used to identify potential nonresponders.

On the role of energy barriers in determining contact angle hysteresis

The thermodynamic model of contact angles on rough, heterogeneous surfaces developed by Long et al. [J. Long, M.N. Hyder, R.Y.M. Huang and P. Chen, Adv. Colloid Interface Sci. 118 (2005) 173] was employed to study the role of energy barriers in determining contact angle hysteresis. Major energy barriers corresponding to metastable states and minor energy barriers corresponding to secondary metastable states were defined. Distributions of major and/or minor energy barriers as a function of apparent contact angle for various surfaces were obtained. The reproducibility of contact angle measurement, the effect of vibrational energy on contact angle hysteresis and the "stick-slip" phenomenon were discussed. Quantitative relations between contact angles and vibrational energy were obtained. It was found that receding contact angles are normally poorly reproducible for hydrophilic surfaces, but for extremely hydrophobic surfaces, advancing contact angles may have a poor reproducibility. When the vibrational energy available to a system increases, the measured advancing contact angle will decrease while the receding angle will increase until both reach a common value: the system equilibrium angle. This finding not only agrees well with the experimental observations in system equilibrium contact angle measurements, but also lays a theoretical foundation for such measurements. A small vibrational energy may result in a "stick-slip" phenomenon.

Humoral and cellular immunity induced by tumor cell vaccine based on the chicken xenogeneic homologous matrix metalloproteinase-2

Matrix metalloproteinase-2 (MMP-2) has been used as a target for cancer immunotherapy. The activation of immunization by breaking immune tolerance to self-MMP-2 may be one of the promising approaches for the treatment of MMP-2-positive tumors. In this study, we constructed the xenogeneic tumor cell vaccine c-MMP-2 by transfecting CT26 and LLC cells with chicken MMP-2 cDNA constructs. MMP-2-specific autoantibodies in sera and tumor cells were found in mice immunized with c-MMP-2. Protection against tumor growth was evaluated in respect of the relative contributions of autoantibodies, CD4+, and CD8+ T cells. Treatment with this vaccine (c-MMP-2) also prolonged the survival time of mice bearing cancer. The specific cytotoxic T-cell responses suggested that the treatment increased CD8+ T-cell activity. The antitumor activity of c-MMP-2 was abrogated by in vivo depletion of CD4+ and CD8+ T-lymphocytes and improved by adoptive transfer of CD4+ and CD8+ T-lymphocytes from the mice treated with c-MMP-2. An alternative DNA vaccination strategy for cancer therapy was identified in this study by eliciting humoral and cellular immunoresponse with a crossreacting transfectant.

Focused ion beam induced deflections of freestanding thin films

Prominent deflections are shown to occur in freestanding silicon nitride thin membranes when exposed to a 50 keV gallium focused ion beam for ion doses between 10(14) and 10(17) ions/cm(2). Atomic force microscope topographs were used to quantify elevations on the irradiated side and corresponding depressions of comparable magnitude on the back side, thus indicating that what at first appeared to be protrusions are actually the result of membrane deflections. The shape in high-stress silicon nitride is remarkably flattopped and differs from that in low-stress silicon nitride. Ion beam induced biaxial compressive stress generation, which is a known deformation mechanism for other amorphous materials at higher ion energies, is hypothesized to be the origin of the deflection. A continuum mechanical model based on this assumption convincingly reproduces the profiles for both low-stress and high-stress membranes and provides a family of unusual shapes that can be created by deflection of freestanding thin films under beam irradiation.

Extraction and protein component analysis of venom from the dissected venom glands of Latrodectus tredecimguttatus

Black widow spiders (genus Latrodectus) have attracted increasing attention due to frequently reported human injuries caused by them and the potential applications of biologically active components in their venoms. Although a number of studies have described the biological properties and structures of several venomous proteins such as latrotoxins, a comprehensive analysis of protein component of the venom from the spider is not available. We used combinative proteomic strategies to assess the protein components of the crude venom collected from Latrodectus tredecimguttatus by extracting the dissected venom glands. The experiments demonstrated that the crude venom of L. tredecimguttatus has a high abundance of acidic proteins with molecular masses greater than 15 kDa, and the content of proteins and peptides of below 15 kDa is low. 86 unique proteins were identified, part of which were contaminations of cellular components during the extraction, determined in comparison with venom obtained by electrostimulation. Except for members of latrotoxin family that were commonly considered as the primary toxic components of the venom, several other special enzymes and proteins were detected such as protease, phosphatase, lysozyme, inhibitory protein, and so on. These protein components, particularly the proteases, were speculated to play important roles in the action of L. tredecimguttatus venom.

Fibrinogen and von Willebrand factor-independent platelet aggregation in vitro and in vivo

BACKGROUND

Fibrinogen (Fg) has been considered essential for platelet aggregation. However, we recently demonstrated formation of occlusive thrombi in Fg-deficient mice and in mice doubly deficient for Fg and von Willebrand factor (Fg/VWF(-/-)).

METHODS AND RESULTS

Here we studied Fg/VWF-independent platelet aggregation in vitro and found no aggregation in citrated platelet-rich plasma of Fg/VWF(-/-) mice. Surprisingly, in Fg/VWF(-/-) plasma without anticoagulant, adenosine diphosphate induced robust aggregation of Fg/VWF(-/-) platelets but not of beta(3)-integrin-deficient (beta(3) (-/-)) platelets. In addition, beta(3) (-/-) platelets did not significantly incorporate into thrombi in Fg/VWF(-/-) mice. This Fg/VWF-independent aggregation was blocked by thrombin inhibitors (heparin, hirudin, PPACK), and thrombin or thrombin receptor activation peptide (AYPGKF-NH(2)) induced aggregation of gel-filtered Fg/VWF(-/-) platelets in 1 mm Ca(2+) PIPES buffer. Notably, aggregation in PIPES buffer was only 50-60% of that observed in Fg/VWF(-/-) plasma. Consistent with the requirement for thrombin in vitro, hirudin completely inhibited thrombus formation in Fg/VWF(-/-) mice. These data define a novel pathway of platelet aggregation independent of both Fg and VWF. Although this pathway was not detected in the presence of anticoagulants, it was observed under physiological conditions in vivo and in the presence of Ca(2+)in vitro.

CONCLUSIONS

beta(3) integrin, thrombin, and Ca(2+) play critical roles in this Fg/VWF-independent aggregation, and both plasma and platelet granule proteins contribute to this process.

Anion effect on the nanostructure of a metal ion binding self-assembling peptide

Effects of copper salts containing different anions (SO(4)(2)(-), Cl(-), and NO(3)(-)) on the self-assembly of a designed peptide EAK16(II)GGH with affinity for Cu(2+) have been investigated. The peptide secondary structure, self-assembled nanostructures, and surface activity were observed to depend strongly on the type of anion. Over a salt concentration range from 0.05 to 10.0 mM, SO(4)(2)(-) induced long fiber formation, whereas Cl(-) and NO(3)(-) caused short fiber formation. The fiber length increased with copper sulfate concentration, but the concentration of copper chloride and copper nitrate did not affect the peptide nanostructures significantly. Analysis by Fourier transform infrared spectroscopy (FTIR) revealed that the addition of the copper salts tended to cause the peptide conformation to change from alpha-helix/random coil to beta-sheet, the extent to which depended on the anion type. This evidence of the anion effect was also supported by surface tension measurements using the axisymmetric drop shape analysis-profile (ADSA-P) technique. An explanation for the effect of anions on the peptide self-assembly was proposed. The divalent anion SO(4)(2)(-) might serve as a bridge by electrostatically interacting with two lysine residues from different peptide molecules, promoting beta-sheet formation. The extensive beta-sheet formation may further promote peptide self-assembly into long fibers. On the other hand, monovalent anions Cl(-) and NO(3)(-) may only electrostatically interact with one charged residue of the peptide; hence, a mixed secondary structure of alpha-helix/random coil and beta-sheet was observed. This observation might explain the predominant formation of short fibers in copper chloride and copper nitrate solutions.

Solvent Effect on the Photophysical Properties of the Anticancer Agent Ellipticine

This paper investigates how solution conditions, especially solvent polarity and hydrogen bonding, affect the fluorescence of ellipticine, a natural plant alkaloid with anticancer activity. A total of 16 solvents that cover a wide range of polarities were tested. The ultraviolet (UV) absorption and fluorescence emission of ellipticine were found to be solvent dependent. The absorption and emission maximum shifted to higher wavelengths (red shift) with increased solvent polarity. The difference in absorption and emission maximum (Stokes' shift) was large, approximately 10,000-11,000 cm-1, in polar solvents (with orientation polarizability Deltaf>0.2) but unusually small, approximately 8900 cm-1, in nonpolar solvents (hexane and cyclohexane). Large Stokes' shifts were due to an intramolecular charge transfer (ICT), which was enabled by large solvent polarity and hydrogen bonding of ellipticine with the solvents. Two transitions were found in the Lippert-Mataga plot between (1) nonpolar and semipolar solvents and between (2) semipolar and polar solvents. The first transition reflected the formation of hydrogen bonds between ellipticine and the solvents whereas the second transition indicated that ellipticine underwent an ICT. In addition, the larger extinction coefficients and the longer lifetime of ellipticine obtained in protic solvents were attributed to the formation of stronger hydrogen bonds. The photophysical response of ellipticine to changes in solvent polarity and hydrogen bond formation could be used to infer the location of ellipticine in a heterogeneous medium, namely liposomes in aqueous solution. A relatively large red shift of emission in liposomes indicated that ellipticine may be in a more polar environment with respect to the lipid bilayer, possibly close to the hydrophilic interface.

Effect of Crop Rotation on Meloidogyne spp. and Pratylenchus spp. Populations in Strawberry Fields in Taiwan

Changes in population levels of Meloidogyne hapla, M. incognita, Pratylenchus coffeae, and P. penetrans were studied in 12 strawberry fields in the Dahu region of Taiwan. Ten potential rotation crops and two cultural practices were evaluated for their effect on nematode populations and influence on strawberry yield. Rotation with rice or taro and the cultural practice of flooding and bare fallowing for four months were found to reduce nematode soil populations to two or fewer nematodes per 100 ml soil. Average strawberry yields increased between 2.4% to 6.3% following taro compared to the bare fallow treatment. Corn suppressed M. incognita and M. hapla populations and resulted in an increased in strawberry yield compared to bare fallow. Other phytopathogens also present in these fields limited taro as the rotation choice for nematode management. Results of this research and economic analysis of the input requirements for various rotation crops, corn and bare fallow were recommended as the most appropriate rotation strategies for nematode management in strawberry in this region.