Preclinical Development and Characterization of Novel Adeno-Associated Viral Vectors for the Treatment of Lipoprotein Lipase Deficiency

Lipoprotein lipase deficiency (LPLD) results from mutations within the lipoprotein lipase (LPL) gene that lead to a complete lack of catalytically active LPL protein. Glybera was one of the first adeno-associated virus (AAV) gene replacement therapy to receive European Medicines Agency regulatory approval for the treatment of LPLD. However, Glybera is no longer marketed potentially due to a combination of economical, manufacturing, and vector-related issues. The aim of this study was to develop a more efficacious AAV gene therapy vector for LPLD. Following preclinical biodistribution, efficacy and non-Good Laboratory Practice toxicity studies with novel AAV1 and AAV8-based vectors in mice, we identified AAV8 pVR59. AAV8 pVR59 delivered a codon-optimized, human gain-of-function hLPLS447X transgene driven by a CAG promoter in an AAV8 capsid. AAV8 pVR59 was significantly more efficacious, at 10- to 100-fold lower doses, compared with an AAV1 vector based on Glybera, when delivered intramuscularly or intravenously, respectively, in mice with LPLD. Efficient gene transfer was observed within the injected skeletal muscle and liver following delivery of AAV8 pVR59, with long-term correction of LPLD phenotypes, including normalization of plasma triglycerides and lipid tolerance, for up to 6 months post-treatment. While intramuscular delivery of AAV8 pVR59 was well tolerated, intravenous administration augmented liver pathology. These results highlight the feasibility of developing a superior AAV vector for the treatment of LPLD and provide critical insight for initiating studies in larger animal models. The identification of an AAV gene therapy vector that is more efficacious at lower doses, when paired with recent advances in production and manufacturing technologies, will ultimately translate to increased safety and accessibility for patients.

Interaction of Hoechst 33342 with POPC Membranes at Different pH Values

Hoechst 33342 (H33342) is a fluorescent probe that is commonly used to stain the DNA of living cells. To do so, it needs to interact with and permeate through cell membranes, despite its high overall charge at physiological pH values. In this work, we address the effect of pH in the association of H33342 with lipid bilayers using a combined experimental and computational approach. The partition of H33342 to 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) lipid membranes was experimentally quantified using fluorescence spectroscopy and isothermal titration calorimetry (ITC) measurements. Quantum chemical calculations were performed to select the most stable isomer of H33342 for the overall charges 0, +1, and +2, expected to predominate across the 5 < pH < 10 range. The interaction of these isomers with POPC bilayers was then studied by both unrestrained and umbrella sampling molecular dynamics (MD) simulations. Both experimental results and computational free energy profiles indicate that the partition coefficient of H33342 displays a small variation over a wide pH range, not exceeding one order of magnitude. The enthalpy variation upon partition to the membrane suggests efficient hydrogen bonding between the probe and the lipid, namely, for the protonated +2 form, which was confirmed in the MD simulation studies. The relatively high lipophilicity obtained for the charged species contrasts with the decrease in their general hydrophobicity as estimated from octanol/water partition. This highlights the distinction between lipophilicity and hydrophobicity, as well as the importance of considering the association with lipid bilayers when predicting the affinity for biomembranes.

Differentiation of Adipose-Derived Stem Cells into Vascular Smooth Muscle Cells for Tissue Engineering Applications

Synthetic grafts have been developed for vascular bypass surgery, however, the risks of thrombosis and neointimal hyperplasia still limit their use. Tissue engineering with the use of adipose-derived stem cells (ASCs) has shown promise in addressing these limitations. Here we further characterized and optimized the ASC differentiation into smooth muscle cells (VSMCs) induced by TGF-β and BMP-4. TGF-β and BMP-4 induced a time-dependent expression of SMC markers in ASC. Shortening the differentiation period from 7 to 4 days did not impair the functional property of contraction in these cells. Stability of the process was demonstrated by switching cells to regular growth media for up to 14 days. The role of IGFBP7, a downstream effector of TGF-β, was also examined. Finally, topographic and surface patterning of a substrate is recognized as a powerful tool for regulating cell differentiation. Here we provide evidence that a non-woven PET structure does not affect the differentiation of ASC. Taken together, our results indicate that VSMCs differentiated from ASCs are a suitable candidate to populate a PET-based vascular scaffolds. By employing an autologous source of cells we provide a novel alternative to address major issues that reduces long-term patency of currently vascular grafts.

In vivo near-infrared fluorescent optical imaging for CNS drug discovery

INTRODUCTION

In vivo imaging technologies have become integral and essential component of drug discovery, development, and clinical assessment for central nervous system (CNS) diseases. Near-infrared (NIR) fluorescence imaging in the range of 650-950 nm is widely used for pre-clinical in vivo imaging studies. The recent expansion of NIR imaging into the shortwave infrared (SWIR, 1000-1700 nm) window enabled improvements in tissue penetration and resolution required for anatomical, dynamic, and molecular neuroimaging with high potential for clinical translation.

AREAS COVERED

This review focuses on the latest progress in near-infrared (NIR)-fluorescent optical imaging modalities with an emphasis on the SWIR window. Advantages and challenges in developing novel organic and inorganic SWIR emitters, with special attention to their toxicology and pharmacology, are discussed. Examples of their application in preclinical imaging of brain function and pathology provide a platform to assess the potential for their clinical translation.

EXPERT OPINION

Propelled through concomitant technological advancements in imaging instrumentation, algorithms and new SWIR emitters, SWIR imaging has addressed key barriers to optical imaging modalities used in pre-clinical studies addressing the CNS. Development of biocompatible SWIR emitters and adoption of SWIR into multi-modal imaging modalities promise to rapidly advance optical imaging into translational studies and clinical applications.

Adventitial growth and lung connective tissue growth factor expression in pulmonary arterioles due to hypobaric hypoxia in broilers

Forty broilers maintained under natural hypobaric hypoxia (2,638 m above sea level) and 20 maintained under relative normoxia (460 m above sea level) were selected as pulmonary hypertensive (PHB) and nonpulmonary hypertensive (NPHB), to estimate the degree of the adventitial vascular thickness in lung arterioles and connective tissue growth factor (CTGF) expression in lung. In each group, the adventitial thickness (%AT) of 20 arterioles with 100 to 250 μm of external diameter was measured in lung samples of 24 and 42-day-old broilers. Also, mRNA extraction and real-time reverse transcription-PCR analysis were used to measure lung CTGF expression. The %AT was higher in PHB at 42 D as compared to NPHB at both ages and PHB at 24 D; however, the same differences were not evidenced at 24 D. In the 2 ages evaluated, differences were observed in the %AT between broilers under hypobaric hypoxia (PHB and NPHB) and under relative normoxia (P < 0.01). In broilers subjected to relative normoxia, no significant differences were found at any of the 2 ages. The expression levels of CTGF mRNA were higher in PHB compared to NPHB at the 2 ages. The %AT was higher in PHB with high levels of expression of CTGF mRNA than those NPHB with low expression of CTGF mRNA. This study showed that adventitial thickening is part of the pulmonary hypertension (PH) physiopathology in broilers exposed to hypobaric hypoxia, in which CTGF appears to be a fibrosis enhancer. Although present data suggest that adventitial engrossment could be a time-dependent process, individual susceptibility and the variable time-course of PH pathophysiology have to be considered.

P1223Attributable risk proportion of uncontrolled low-density lipoprotein cholesterol in recurrent acute coronary syndromes

Background

Coronary heart disease is chronic condition that usually has recurrent events. Risk factors for incident coronary heart disease are well known conditions related to recurrences have not been clearly outlined. Attributable risk proportion (ARP) refers to the proportion of incident cases in subjects exposed to risk factors that are attributable to that risk factor so we analysed ARP in wide cohort of patients admitted for an acute coronary syndrome (ACS).

Methods

Cross-sectional analysis of all patients admitted in two hospitals between January 2006 and December 2016. ARP was calculated by the equation: prevalence in exposed – (prevalence in exposed/odds ratio). LDL uncontrolled was codified as >70 mg/dl in patients with previous cardiovascular disease; >100 mg/dl in patients with diabetes without previous cardiovascular disease or; >155 mg/dl in patients without cardiovascular disease.

Results

We included 7,518 patients, mean age 66.9 (12.9) years, 72.5% males, median GRACE score 143.2 (40.3) and 35.3% STEMI. Previous coronary heart disease total was present in 2,032 (23.2%) patients and they had statistically higher mean age (70.6±11.11 vs. 65.8±13.3), prevalence of diabetes (37.9% vs. 25.3%) and hypertension (72.9% vs. 53.3%) and lower smoking habit (15.5% vs. 30.9%). LDLc was lower in patients with previous coronary heart disease (90.3±33.8 vs. 111.7±38.1; p<0.01), as well as HDLc (33.5±14.29 vs. 35.9±35.5; p<0.01) and haemoglobin (13.5±3.7 vs. 14.0±2.4; p<0.01). Uncontrolled LDLc was present in 83.4% of the patients with previous coronary heart disease, in contrast to the 28.7% of patients without previous coronary heart disease; this resulted in an ARP of 13.8%. The ARP for diabetes and hypertension were 1.6% and 1.4%, respectively.

Conclusions

The proportion of attributable risk of uncontrolled LDL on recurrent ACS is 13.8% and, therefore, 1 out of every 7 recurrent ACS could be prevented by an accurate LDLc control.

P1759Elevated NT-pro BNP predicts Heart Failure re-hospitalizations after an acute coronary syndrome

Background

NT pro-BNP is a well-established biomarker of tissue congestion and has prognostic value in patients with heart failure (HF) and, also, with acute coronary syndrome (ACS). Nonetheless, there is scarce evidence on the predictive capacity of NT pro-BNP for HF re-admission after an ACS.

Objective

To test whether elevated values of NT pro-BNP can predict subsequent hospitalizations for HF in patients discharged after an ACS.

Methods

We performed a prospective study of all patients discharged after an ACS in a single center. HF re-admission was analysed by competing risk regression, taking all-cause mortality as a competing event, and results are presented as sub-Hazard Ratio (sHR); recurrent hospitalizations were tested by negative binomial regression and results are presented as incidence risk ratio (IRR).

Results

We included 1,679 patients, mean age 70.1 (29.7) year, 71.9% males, 41.4% STEMI and mean GRACE score 151.7 (44.4). Median NT pro-BNP was 948.2 pg/ml (IQ range 274.5–2923) and patients were divided in <300U (27.0%), 300–600 pg/ml (13.4%), 600–1000 pg/ml (10.8%) and >1000 pg/ml (46.7%) A total of 132 (5.9%) died within hospitalization and follow-up was available 98% of the patients, with a median follow-up of 33 months (IQ range 16–59). A total of 220 patients (13.1%) had at least one hospital re-admission of HF and 126 (7.5%) had more than one re-hospitalization for HF. Patients with NT pro-BNP had higher un-adjusted HF re-admissions (22.2% vs. 4.4%; p<0.01). Cardiovascular mortality increased significantly in each category of NT pro-BNP (3.8%; 8.0%; 7.7%; 18.5%) as well as all-cause mortality (0.1%; 12.4%; 11.6%; 25.3%), first HF readmission (2.7%; 7.1%; 5.5%; 23.5%); patients with NT pro-BNP had higher rates of recurrent HF readmissions: 11.6/1000 vs. 2.4/1000 patients/years (p<0.01). Multivariate analyses, adjusted by age, gender, GRACE score, left ventricle ejection fraction, revascularization and medical treatments at discharge, identified that NT pro-BNP >1000 pg/ml was associated to HF re-hospitalization (sHR: 2.60 95% CI 1.12–5.95) and recurrent hospitalizations (IRR: 1.10 95% CI 1.04–1.14).

Conclusions

NT pro-BNP >1000 pg/ml is an accurate risk factor for first and recurrent HF rehospitalisations after an ACS.

Interaction of Bile Salts With Lipid Bilayers: An Atomistic Molecular Dynamics Study

Bile salts (BS) are biosurfactants crucial for emulsification and intestinal absorption of cholesterol and other hydrophobic compounds such as vitamins and fatty acids. Interaction of BS with lipid bilayers is important for understanding their effects on membranes properties. The latter have relevance in passive diffusion processes through intestinal epithelium such as reabsorption of BS, as well as their degree of toxicity to intestinal flora and their potential applications in drug delivery. In this work, we used molecular dynamics simulations to address at the atomic scale the interactions of cholate, deoxycholate, and chenodeoxycholate, as well as their glycine conjugates with POPC bilayers. In this set of BS, variation of three structural aspects was addressed, namely conjugation with glycine, number and position of hydroxyl substituents, and ionization state. From atomistic simulations, the location and orientation of BS inside the bilayer, and their specific interactions with water and host lipid, such as hydrogen bonding and ion-pair formation, were studied in detail. Membrane properties were also investigated to obtain information on the degree of perturbation induced by the different BS. The results are described and related to a recent experimental study (Coreta-Gomes et al., 2015). Differences in macroscopic membrane partition thermodynamics and translocation kinetics are rationalized in terms of the distinct structures and atomic-scale behavior of the bile salt species. In particular, the faster translocation of cholate is explained by its higher degree of local membrane perturbation. On the other hand, the relatively high partition of the polar glycine conjugates is related to the longer and more flexible side chain, which allows simultaneous efficient solvation of the ionized carboxylate and deep insertion of the ring system.

Frequency and clinical impact of CDKN2A/ARF/CDKN2B gene deletions as assessed by in-depth genetic analyses in adult T cell acute lymphoblastic leukemia

Recurrent deletions of the CDKN2A/ARF/CDKN2B genes encoded at chromosome 9p21 have been described in both pediatric and adult acute lymphoblastic leukemia (ALL), but their prognostic value remains controversial, with limited data on adult T-ALL. Here, we investigated the presence of homozygous and heterozygous deletions of the CDKN2A/ARF and CDKN2B genes in 64 adult T-ALL patients enrolled in two consecutive trials from the Spanish PETHEMA group. Alterations in CDKN2A/ARF/CDKN2B were detected in 35/64 patients (55%). Most of them consisted of 9p21 losses involving homozygous deletions of the CDKNA/ARF gene (26/64), as confirmed by single nucleotide polymorphism (SNP) arrays and interphase fluorescence in situ hybridization (iFISH). Deletions involving the CDKN2A/ARF/CDKN2B locus correlated with a higher frequency of cortical T cell phenotype and a better clearance of minimal residual disease (MRD) after induction therapy. Moreover, the combination of an altered copy-number-value (CNV) involving the CDKN2A/ARF/CDKN2B gene locus and undetectable MRD (≤ 0.01%) values allowed the identification of a subset of T-ALL with better overall survival in the absence of hematopoietic stem cell transplantation.

Effect of Acyl Chain Length on the Rate of Phospholipid Flip-Flop and Intermembrane Transfer

The rate at which phospholipids equilibrate between different membranes and between the non-polar environments in biological fluids is of high importance in the understanding of biomembrane diversity, as well as in the development of liposomes for drug delivery. In this work, we characterize the rate of insertion into and desorption from POPC bilayers for a homologous series of amphiphiles with the fluorescent NBD group attached to phosphoethanolamines of different acyl chain lengths, NBD-diC _n -PE with n = 6, 8, 10, and 12. The rate of translocation between bilayer leaflets was also characterized, providing all the relevant parameters for their interaction with lipid bilayers. The results are complemented with data for NBD-diC₁₄-PE obtained from literature (Abreu et al. Biophys J 87:353-365, 2004; Moreno et al. Biophys J 91:873-881, 2006). The rate of translocation between the POPC leaflets is not dependent on the length of the acyl chains, while this affects strongly the rate of desorption from the bilayer. Insertion in the POPC bilayer is not diffusion controlled showing a significant dependence on the acyl chain length and on temperature. The results obtained are compared with those previously reported for NBD-LysoC₁₄-PE (Sampaio et al. Biophys J 88:4064-4071, 2005), and with the homologous series of single chain amphiphiles NBD-C _n (Cardoso et al. J Phys Chem B 114:16337-16346, 2010; J Phys Chem B 115:10098-10108, 2011). This allows the establishment of important relations between the rate constants for interaction with the lipid bilayers and the structural properties of the amphiphiles, namely the total surface and the cross-section of their non-polar region.

A High Fundamental Frequency (HFF)-based QCM Immunosensor for Tuberculosis Detection

BACKGROUND

Tuberculosis, one of the oldest diseases affecting human beings, is still considered as a world public health problem by the World Health Organization.

METHOD & MATERIAL

Therefore, there is a need for new and more powerful analytical methods for early illness diagnosis. With this idea in mind, the development of a High Fundamental Frequency (HFF) piezoelectric immunosensor for the sensitive detection of tuberculosis was undertaken. A 38 kDa protein secreted by Mycobacterium tuberculosis was first selected as the target biomarker. Then, specific monoclonal antibodies (MAbs) were obtained. Myc-31 MAb, which showed the highest affinity to the analyte, was employed to set up a reference enzyme-linked immunosorbent assay (ELISA) with a limit of detection of 14 ng mL-1 of 38 kDa antigen.

RESULTS & DISCUSSION

For the development of the HFF piezoelectric immunosensor, 100 MHz quartz crystals were used as transducer elements. The gold electrode surface was functionalized by covalent immobilization of the target biomarker through mixed self-assembled monolayers (mSAM) of carboxylic alkane thiols. A competitive immunoassay based on Myc-31 MAb was integrated with the transducer as sensing bio-recognition event. Reliable assay signals were obtained using low concentrations of antigen for functionalization and MAb for the competitive immunoassay. Under optimized conditions, the HFF immunosensor calibration curve for 38 kDa determination showed a limit of detection as low as 11 ng mL-1 of the biomarker. The high detectability attained by this immunosensor, in the picomolar range, makes it a promising tool for the easy, direct and sensitive detection of the tuberculosis biomarker in biological fluids such as sputum.

Effect of ethyleneoxide groups of anionic surfactants on lipase activity

The use of enzymes in laundry and dish detergent products is growing. Such tendency implies dedicated studies to understand surfactant-enzyme interactions. The interactions between surfactants and enzymes and their impact on the catalytic efficiency represent a central problem and were here evaluated using circular dichroism, dynamic light scattering, and enzyme activity determinations. This work focuses on this key issue by evaluating the role of the ethyleneoxide (EO) groups of anionic surfactants on the structure and activity of a commercial lipase, and by focusing on the protein/surfactant interactions at a molecular level. The conformational changes and enzymatic activity of the protein were evaluated in the presence of sodium dodecyl sulfate (SDS also denoted as SLE₀ S) and of sodium lauryl ether sulfate with two EO units (SLE₂ S). The results strongly suggest that the presence of EO units in the surfactant polar headgroup determines the stability and the activity of the enzyme. While SDS promotes enzyme denaturation and consequent loss of activity, SLE₂ S preserves the enzyme structure and activity. The data further highlights that the electrostatic interactions among the protein groups are changed by the presence of the adsorbed anionic surfactants being such absorption mainly driven by hydrophobic interactions. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1276-1282, 2016.

Quaternary ammonium surfactant structure determines selective toxicity towards bacteria: mechanisms of action and clinical implications in antibacterial prophylaxis

OBJECTIVES

Broad-spectrum antimicrobial activity of quaternary ammonium surfactants (QAS) makes them attractive and cheap topical prophylactic options for sexually transmitted infections and perinatal vertically transmitted urogenital infections. Although attributed to their high affinity for biological membranes, the mechanisms behind QAS microbicidal activity are not fully understood. We evaluated how QAS structure affects antimicrobial activity and whether this can be exploited for use in prophylaxis of bacterial infections.

METHODS

Acute toxicity of QAS to in vitro models of human epithelial cells and bacteria were compared to identify selective and potent bactericidal agents. Bacterial cell viability, membrane integrity, cell cycle and metabolism were evaluated to establish the mechanisms involved in selective toxicity of QAS.

RESULTS

QAS toxicity normalized relative to surfactant critical micelle concentration showed n-dodecylpyridinium bromide (C12PB) to be the most effective, with a therapeutic index of ∼10 for an MDR strain of Escherichia coli and >20 for Neisseria gonorrhoeae after 1 h of exposure. Three modes of QAS antibacterial action were identified: impairment of bacterial energetics and cell division at low concentrations; membrane permeabilization and electron transport inhibition at intermediate doses; and disruption of bacterial membranes and cell lysis at concentrations close to the critical micelle concentration. In contrast, toxicity to mammalian cells occurs at higher concentrations and, as we previously reported, results primarily from mitochondrial dysfunction and apoptotic cell death.

CONCLUSIONS

Our data show that short chain (C12) n-alkyl pyridinium bromides have a sufficiently large therapeutic window to be good microbicide candidates.

Histological assessment of angiogenesis in the hypoxic central nervous system

Angiogenesis, the sprouting of new capillaries from preexisting vessels, is an integral part of both normal development and numerous pathological conditions such as tumor growth, inflammation, and stroke. The development of angiogenesis assays has been critical in understanding this process in both the context of disease and normal physiology. With the growing availability of antibodies against angiogenic markers as well as advances in microscopy and imaging analysis software, a more comprehensive assessment of the angiogenesis process is beginning to take form (Milner et al., Stroke 39:191-197, 2008; Freitas-Andrade et al., J Cereb Blood Flow Metab 32:663-675, 2012; Li et al., Glia 58:1157-1167, 2010; Dore-Duffy and LaManna, Antioxid Redox Signal 9:1363-1371, 2007). This chapter describes an in vivo method of inducing brain angiogenesis in mice by chronic exposure to mild hypoxia. In addition, a detailed procedure of quantifying angiogenesis using multiple immunofluorescent labeling of mouse brain tissue sections is also presented.

A novel automated cell-seeding device for tissue engineering of tubular scaffolds: design and functional validation

Obtaining an efficient, uniform and reproducible cell seeding of porous tubular scaffolds constitutes a major challenge for the successful development of tissue-engineered vascular grafts. In this study, a novel automated cell-seeding device utilizing direct cell deposition, patterning techniques and scaffold rotation was designed to improve the cell viability, uniformity and seeding efficiency of tubular constructs. Quantification methods and imaging techniques were used to evaluate these parameters on the luminal and abluminal sides of fibrous polymer scaffolds. With the automated seeding method, a high cell-seeding efficiency (~89%), viability (~85%) and uniformity (~85-92%) were achieved for both aortic smooth muscle cells (AoSMCs) and aortic endothelial cells (AoECs). The duration of the seeding process was < 8 min. Initial cell density, cell suspension in matrix-containing media, duration of seeding process and scaffold rotation were found to affect the seeding efficiency. After few days of culture, a uniform longitudinal and circumferential cell distribution was achieved without affecting cell viability. Both cell types were viable and spread along the fibres after 28 h and 6 days of static incubation. This new automated cell-seeding method for tubular scaffolds is efficient, reliable and meets all the requirements for clinical applicability.

Development of a compliant and cytocompatible micro-fibrous polyethylene terephthalate vascular scaffold

Bioengineering approaches have been intensively applied to create small diameter vascular grafts using artificial materials. However, a fully successful, high performing and anti-thrombogenic structure has not been achieved yet. In this study, we have designed and fabricated a novel non-woven fibrous vascular graft with biomechanical properties closely resembling those of native vessels. Vascular cell growth, preservation of cell phenotype, retention of vasoactive properties, as well as the effect of gelatin coating on the cellular interaction with the scaffolds under static and shear stress conditions were investigated. The non-woven fibrous scaffolds were made from melt blown polyethylene terephthalate fiber webs stacked by means of a consolidation technique. The scaffold variables were fiber diameter distribution and the number of consolidated web stacks. SEM analysis confirmed various fiber diameter and pore size ranges corresponding to the different conditions. The scaffolds showed burst pressure values of ∼1500 mmHg and compliance (8.4 ± 1.0 × 10(-2) % mmHg(-1) ) very similar to those of native arteries (∼8 × 10(-2) % mmHg(-1) ). The structure with the smallest fiber diameter range (1-5 μm) and pore size range (1-20 μm) was the most suitable for the growth of human brain endothelial cells and aortic smooth muscle cells. The cells maintained their specific cell phenotype, expressed collagen and elastin and produced cAMP in response to α-calcitonin gene-related peptide. However, under shear stress conditions (0.9 dyne cm(-2) ), only 30% of the cells were retained in both uncoated and gelatin-coated scaffolds indicating the need for improving the cell retention capacity of these structures, which is our future research direction. This study indicates that the biomechanical and biocompatible properties of this novel vascular scaffold are promising for the development of a vascular graft with similar characteristics to those of native vessels.

Chain length effect on the binding of amphiphiles to serum albumin and to POPC bilayers

The interaction of small molecules, such as drugs or metabolites, with proteins and biomembranes is of fundamental importance for their bioavailability. The systematic characterization of the binding affinity for structurally related ligands may provide rules that allow its prediction for any other relevant molecule. In this work we have studied a homologous series of fluorescent fatty amines with the fluorescent moiety 7-nitrobenz-2-oxa-1,3-diazol-4-yl covalently bound to the amine group (NBD-C(n); n = 4, 6, 8, 10, 12, 14, and 16) in aqueous solution and associated with BSA or lipid bilayers. We have found a linear dependence with the length of the alkyl chain, up to NBD-C(10), for the Gibb's free energy of partition between the aqueous solution and 1-palmitoyl-2-oleoyl phosphatidylcholine bilayers equal to ΔΔG = -2.5 ± 0.3 kJ/mol per methylene group. Additionally, the amphiphiles interacted efficiently with bovine serum albumin, and it was inhibited by fatty acids indicating that binding occurs to the fatty acids highest affinity binding site. The association of the amphiphiles with BSA and POPC bilayers was performed at different temperatures (15-35 °C) allowing for the calculation of the enthalpic and entropic contributions. A value of ΔH = -15 ± 4 kJ/mol was obtained for all amphiphiles and binding agents. The entropy contribution was always positive and increased with the length of the alkyl chain. The location of the ligand in the biological membrane is also of high relevance, namely because this will determine its effect on biomembrane properties at high ligand concentrations. With this goal, we have measured some photophysical properties of the amphiphiles inserted in POPC bilayers, and we found no significant variation along the series, indicating that the NBD group is located in a region with similar properties regardless of the length of the nonpolar group. An exception was noted for the case of NBD-C(14) whose parameters were somewhat different from the trend observed.

Identification of secreted proteins regulated by cAMP in glioblastoma cells using glycopeptide capture and label-free quantification

Exposure of glioblastoma U87MG cells to a cAMP analog leads to a decrease in proliferation, invasion, and angiogenic potential. Here, we apply a label-free MS-based approach to identify formerly N-linked glycopeptides that change in abundance upon cAMP treatment. Over 150 unique glycopeptides in three biological repetitions were quantified, leading to the identification of 14 upregulated proteins and 21 downregulated proteins due to cAMP treatment. Of these, eight have been validated, either through comparison with microarray data or by Western blot. We estimate our ability to identify differentially expressed peptides at greater than 85% in a single biological repetition, while the analysis of multiple biological repetitions lowers the false positive rate to approximately 2%. Many of the proteins identified in this study are involved in cell signaling and some, such as Tenascin C, Cathepsin L, Neuroblastoma suppressor of tumorigenicity, and AXL/UFO tyrosine-protein kinase receptor, have been previously shown to be involved in glioblastoma progression. We also identify several semitryptic peptides that increase in abundance upon cAMP treatment, suggesting that cAMP regulates protease activity in these cells. Overall, these results demonstrate the benefits of using a highly specific enrichment method for quantitative proteomic experiments.

[Circumscript myositis ossificans in a four-year-old boy]

We present the case of a 4 year old boy with no previous personal or family history of interest, who attended the Paediatric Department of our hospital after a physical examination revealed a painful induration in the left arm which had increased in size; imaging tests were consistent with a calcified mass in soft tissues, without cortical involvement, suspected of being malignant. Two-phase bone scintigraphy was requested in which a soft tissue lesion, not suggestive of malignancy, was detected. The biopsy was negative for malignant cells. However, in view of the progressive increase in size of the lesion, FDG positron emission tomography (FDG-PET) was performed, showing a hypermetabolic mass consistent with malignancy in the left arm, for which the patient underwent surgery for suspected possible parosteal osteosarcoma.

Glioblastoma-secreted factors induce IGFBP7 and angiogenesis by modulating Smad-2-dependent TGF-beta signaling

Insulin-like growth factor-binding protein 7 (IGFBP7) is a selective biomarker of glioblastoma (GBM) vessels, strongly expressed in tumor endothelial cells and vascular basement membrane. IGFBP7 gene regulation and its potential role in tumor angiogenesis remain unclear. Mechanisms of IGFBP7 induction and its angiogenic capacity were examined in human brain endothelial cells (HBECs) exposed to tumor-like conditions. HBEC treated with GBM cell (U87MG)-conditioned media (-CM) exhibited fourfold upregulation of IGFBP7 mRNA and protein compared to control cells. IGFBP7 gene regulation in HBEC was methylation independent. U87MG-CM analysed by enzyme-linked immunosorbent assay contained approximately 5 pM transforming growth factor (TGF)-beta1, a concentration sufficient to stimulate IGFBP7 in HBEC to similar levels as U87MG-CM. Both pan-TGF-beta-neutralizing antibody (1D11) and the TGF-beta1 receptor (activin receptor-like kinase 5, ALK5) antagonist, SB431542, blocked U87MG-CM-induced IGFBP7 expression in HBEC, indicating that TGF-beta1 is an important tumor-secreted effector capable of IGFBP7 induction in endothelial cells. HBEC exposed to either U87MG-CM or IGFBP7 protein exhibited increased capillary-like tube (CLT) formation in Matrigel. Both TGF-beta1- and U87MG-CM-induced Smad-2 phosphorylation and U87MG-CM-induced CLT formation in HBEC were inhibited by the ALK5 antagonist, SB431542. These data suggest that proangiogenic IGFBP7 may be induced in brain endothelial cells by TGF-betas secreted by GBM, most likely through TGF-beta1/ALK5/Smad-2 pathway.

Endothelin 1, its Endothelin Type A Receptor, Connective Tissue Growth Factor, Platelet-Derived Growth Factor, and Adrenomedullin Expression in Lungs of Pulmonary Hypertensive and Nonhypertensive Chickens

Twenty-four 1-d-old broilers were distributed in 2 groups, pulmonary hypertensive broilers (PHB) and pulmonary nonhypertensive broilers (NPHB), to estimate possible differences between them in the expression of endothelin 1 (ET-1) and its type A receptor, connective tissue growth factor, platelet-derived growth factor, and adrenomedullin expression in the lungs. For this purpose, total RNA extraction and real-time PCR analysis were used. Endothelin 1 mRNA levels in the lungs of PHB were significantly higher than the corresponding level in NPHB (P < 0.001). In contrast, the opposite was true for ET-1 type A receptor mRNA levels (P < 0.001). Connective tissue growth factor mRNA levels in the lungs of PHB were significantly higher than in the lungs of NPHB (P < 0.01). However, no differences were encountered between the 2 groups of broilers in platelet-derived growth factor mRNA expression (P > 0.05). Adrenomedullin mRNA levels in the lungs of PHB were significantly higher than in NPHB (P < 0.01). It has been demonstrated for the first time that ET-1, connective tissue growth factor, and adrenomedullin are upregulated in the lungs of PHB. Furthermore, it is suggested that these peptides may play a major role in pulmonary hypertension pathophysiology. Present data might provide clues for future research directions such as genetic selection and therapeutic intervention to revert the process of pulmonary vasoconstriction and vascular remodeling. Major research goals could be to find endothelium-derived factors that probably trigger endothelial dysfunction, as well as possible interactions with already identified molecules which also intervene in the pulmonary response to hypoxia.

Molecular markers of extracellular matrix remodeling in glioblastoma vessels: microarray study of laser-captured glioblastoma vessels

Glioblastoma multiforme (GBM) are the most malignant and vascularized brain tumors. The aberrant vascular phenotype of GBM could be exploited for diagnosis or therapeutic targeting. This study identified new molecular markers of GBM vessels, using a combination of laser capture microdissection (LCM) microscopy, RNA amplification, and microarray analyses to compare vessels from nonmalignant human brain and GBM tumors. Forty-two genes were differentially expressed in GBM vessels compared to nonmalignant brain vessels. Validation of differentially expressed genes was performed by literature mining, Q-PCR, and immunohistochemistry. Among the differentially expressed genes, only 64% were previously associated with vessels, angiogenesis, gliomas, and/or cancer. The upregulation of genes encoding secreted extracellular proteins IGFBP7 and SPARC was confirmed by Q-PCR in LCM-captured vessels. Whereas SPARC and IGFBP7 protein were absent in nonmalignant brain vessels, a distinct immunoreactivity patterns were observed in GBM sections whereby SPARC was strongly expressed in perivascular cells adjacent to GBM vessels while GBM endothelial cells were immunostained for IGFBP7. IGFBP7 immunoreactivity was also detected on the abluminal side of GBM vessels deposited between strands of vascular basal lamina. The study discerns unique molecular characteristics of GBM vessels compared with nonmalignant brain vessels that could potentially be used for diagnostic or therapeutic purposes.

Eosinophil-selective mediators in human strongyloidiasis

Strongyloides stercoralis infection is characterized by the production of IgE and eosinophils in peripheral blood. Experimental studies have demonstrated that eosinophils play an important role in protection against Strongyloides stercoralis, but the mechanisms regulating eosinophils are not known. In this study we have focused on analysing the molecules that selectively regulate eosinophil migration, namely eotaxin and interleukin-5 (IL-5), using an enzyme-linked immunosorbent assay in patients with strongyloidiasis. Serum expression of eotaxin and IL-5 were significantly increased in patients compared with the control group. This rise suggests that selective mediators of the eosinophil can have a role in immunity against S. stercoralis in human infection.

Erythrophagocytosis in de novo-philadelphia-positive acute leukemia of ambiguous lineage

Erythrophagocytosis by neoplastic cells in acute leukemia has been most frequently associated with FAB M4 and M5 subtypes, with the t(8;16) and with C-MOZ rearrangements, however it is exceptional in acute lymphoblastic leukemia and has not been previously reported in Philadelphia-positive (Ph+) acute leukemia. We herein present a case of Ph+ acute leukemia of ambiguous lineage in which erythrophagocytosis is an outstanding feature. The implications between the different postulated leukemogenic pathways and the hypothesized mechanism of erythrophagocytosis are concisely reviewed and discussed.

Metastasis-associated protein S100A4 induces angiogenesis through interaction with Annexin II and accelerated plasmin formation

Many advanced tumors overexpress and secrete the S100A4 protein that is known to promote angiogenesis and metastasis development. The mechanisms of this effect and the endothelial receptor for S100A4 are both still unknown. Here we report that extracellular S100A4 interacts with annexin II, an endothelial plasminogen co-receptor. Co-localization and direct binding of S100A4 and annexin II were demonstrated, and the binding site was identified in the N-terminal region of annexin II. S100A4 alone or in a complex with annexin II accelerated tissue plasminogen activator-mediated plasminogen activation in solution and on the endothelial cell surface through interaction of the S100A4 C-terminal lysines with the lysine-binding domains of plasminogen. A synthetic peptide corresponding to the N terminus of annexin II prevented S100A4-induced plasmin formation in the endothelial cell culture. Local plasmin formation induced by circulating S100A4 could contribute to tumor-induced angiogenesis and metastasis formation that makes this protein an attractive target for new anti-cancer and anti-angiogenic therapies.

Comparative toxic effects of formulated simazine on Vibrio fischeri and gilthead seabream (Sparus aurata L.) larvae

The use of Early Life Stage (ELS) tests is a useful tool in risk assessment. The purpose of this study was to compare the sensitivity of the seabream (Sparus aurata) larvae with the extensively used Microtox test on a commercial formulation containing simazine, an s-triazine herbicide. To this end, survival, growth and histopathological changes displayed by seabream yolk sac larvae exposed during 72 h post-hatching to nominal concentrations of the commercial preparation up to its saturating concentration in water, and bioluminescence of the marine bacteria Vibrio fischeri (Microtox) were studied. Survival of larvae after three days of exposure was significantly reduced in the highest (4.5 mg/l) concentration, but no effects on growth were found in any of the simazine treatments. The 72 h LC50 value for yolk sac larvae was estimated as 4.19 mg/l. Commercial grade simazine did not exert any significant toxicity to the marine bacterium V. fischeri at the concentrations tested.

Toxicity of a commercial herbicide containing terbutryn and triasulfuron to seabream (Sparus aurata L.) larvae: a comparison with the Microtox test

The present study aimed to compare the sensitivity of larvae of the gilthead seabream (Sparus aurata), a valuable fish species of the Spanish South Atlantic littoral, with the extensively used Microtox test on a commercial herbicide formulation containing terbutryn (59.4%) and triasulfuron (0.6%). To this purpose, mortality displayed by endogenous feeding S. aurata larvae exposed during 72 h post-hatching to nominal concentrations of the commercial formulation and bioluminescence of the marine bacterium Vibrio fischeri were compared. Histomorphological changes were also studied. Clearly, the S. aurata assay was the more sensitive indicator of toxicity for this herbicide. The 72-h concentration lethal to 50% of the individuals (LC(50)) found for yolk sac larvae was 1.41 mg/L. This value was more than one order of magnitude below the 15-min EC(50) found for V. fischeri (15.94 mg/L). Growth of the larvae was not significantly affected by a terbutryn-triasulfuron mixture at concentrations up to 1.56 mg/L, the maximum at which there was some proportion of survival.

[Causes of obesity]

The aetiology and treatment of obesity requires a knowledge of the mechanisms that control the homeostasis of the fuel substrates and adiposity. The processes of regulation adjust the supply of macronutrients and energy demands with the aim of maintaining a stable body mass. In the light of the most recent research, the hypothesis can be advanced that the control of body weight and its composition depends on an axis integrated by three self-regulated components: appetite, stores thermogenesis and fat deposits. The most important factors involved in obesity seem to be dietary habits diet and physical activity, which are affected by genes, which in their turn affect energy expenditure, the metabolism of energy substrates and food consumption. However, the growing rates of obesity cannot be explained exclusively by genetic causes, since they are in some cases associated with the consumption of diets with a high energy density or rich in fat, and by a growing sedentary life style in society, both in developed and developing countries. The study of genetics and life style involved in the increase of body weight and obesity can facilitate the implementation of preventive actions.

[Adipose tissue: a storage and secretory organ]

The adipose tissue plays a fundamental role in maintaining the energy balance in mammals. During periods of high energy intake, the adipocytes store energy in the form of fat (triglycerides), which can be mobilized as free fatty acids during energy deprivation. Adipose tissue can no longer be considered only as a passive tissue that simply stores energy. Some recent discoveries have made it evident that this is a very active endocrine tissue that secretes important molecules related to different processes such as the immune response (TNF alpha) the regulation of food intake and expenditure of energy (leptin, Acrp30/adipoQ) and the vascular function (angiotensin and plasminogen activator inhibitor type 1). Alterations in the growth, development and function of the adipose tissue might therefore be involved in the development of different pathologies such as obesity, insulin resistance and type 2 diabetes, hypertension and atherosclerosis. A deeper understanding of the adipose tissue (morphology, development-adipogenesis, role in the metabolism and in the regulation of body weight, endocrine functions.) is needed for an adequate study of the underlying aspects in the development of obesity.

[Sporadic Creutzfeldt-Jakob disease: phenotypic variability]

Prion disease are characterized by cerebral deposition of an abnormal protease-resistant isoform of a membrane-bound glycoprotein called prion protein. Sporadic Creutzfeldt-Jakob disease (CJDs) is the most frequent, accounting for approximately 85% of all human prion disease. The identification of a new variant of Creutzfeldt-Jakob disease has reinforced the need for a detailed analysis of phenotypic variability of CJDs. CJDs is typically characterized by rapidly progressive dementia, myoclonus, periodic sharp-wave electroencephalographic activity, and wide-spread spongiform degeneration. However, variations in clinical presentation, disease duration, as well as type and distribution of lesion have been consistently observed. The physicochemical properties of PrPsc in conjunction with the PRNP codon 129 genotype largely determine this phenotypic variability. Continued attention to clinically atypical cases is required to monitor the real incidence of CJDs. To reach this goal neuropathological examination, including the search for PrPsc, and molecular genetic analysis of human prion protein gene (PRNP) should be increasingly applied to atypical neurodegenerative diseases.

Could ivermectin have a synergic effect with albendazole in hydatidosis therapy?

The efficacy of a combination of ivermectin (IVM) and albendazole (ABZ) used as a chemoprophylactic treatment and as treatment of secondary hydatidosis is described for the first time. IVM treatment alone was not effective against Echinococcus granulosus, either when the protoscolices were recently inoculated or when they had developed to the metacestode stage. However, the efficacy of IVM and ABZ when used in combination as a prophylactic treatment was 95.72% and 87% with respect to the number and the wet weight of cysts, respectively. These results were higher than in the treatment of secondary hydatidosis, which were 44.8% and 45.26%, respectively. The ultrastructural changes in the germinal layer of the cysts after the treatments are also described.

Efficacy of the non-peptide CGRP receptor antagonist BIBN4096BS in blocking CGRP-induced dilations in human and bovine cerebral arteries: potential implications in acute migraine treatment

Calcitonin gene-related peptide (CGRP) is a potent vasodilator in brain vessels and it has been implicated in the pathogenesis of migraine headache. Blocking post-junctional CGRP receptors, mediators of trigeminal-induced vasodilation, has been suggested as a potential antimigraine strategy. In this study, we tested the ability of a new non-peptide CGRP receptor antagonist, BIBN4096BS, to inhibit the CGRP-induced dilation in human and/or bovine brain vessels and compared it to that of the antagonist alpha-CGRP(8-37). BIBN4096BS and alpha-CGRP(8-37) both blocked the alpha-CGRP-induced dilation in bovine middle artery segments with respective potency (pK(B) values) of 6.3 and 7.8. In human pial vessels, BIBN4096BS was particularly potent. When tested at 10(-14)-10(-9) M concentrations, it induced a rightward shift in the alpha-CGRP concentration-response curve and yielded a biphasic Schild plot suggesting interaction with more than one receptor population, as was also indicated by the significant best fit of the alpha-CGRP-induced dilation in human brain vessels with a two receptor site interaction. Schild plot analysis in the linear portion of the BIBN4096BS inhibition curve revealed interaction with one high affinity site (pA(2) value approximately 14). In bovine vessels, both alpha-CGRP(8-37) and BIBN4096BS concentration-dependently reversed a pre-established CGRP-induced dilation ( approximately 59 and 85%, respectively), BIBN4096BS being approximately tenfold more potent than alpha-CGRP(8-37) (respective pIC(50) values of 7.5 and 6.75). In human middle cerebral and middle meningeal arteries, BIBN4096BS reversed the alpha-CGRP-induced dilation (> or =70%) by interaction with two different receptor populations: it exhibited a high affinity for one population (pIC(50) value approximately 13) and a lower affinity for the other (pIC(50) value approximately 8). The present data demonstrate that BIBN4096BS is a very potent antagonist that could, depending on its bioavailability and in vivo affinity, be of potential benefit in the acute treatment of migraine headache by blocking and/or reversing the CGRP-mediated dilation of intracranial vessels induced by activation of trigeminovascular afferents.

Could ivermectin have a synergic effect with albendazole in hydatidosis therapy?

The efficacy of ivermectin (IVM) alone, albendazole (ABZ) alone and a combination of both (IVM + ABZ) against Echinococcus granulosus protoscolices was studied by means of in vitro incubation. The maximum protoscolicidal effect was detected when we used IVM+ABZ in combination. In this case, protoscolex viability dropped to 35% in comparison with 50% for IVM alone and 82.5% with ABZ alone 18 days post-incubation. Only the protoscolices incubated with IVM + ABZ did not develop into cysts following their inoculation into mice. The changes in ultrastructure induced in the protoscolices after the different drug incubations are also described. The incubation of cysts with IVM and IVM + ABZ shows that IVM + ABZ in combination is more effective than IVM alone as only when we incubated the cysts with IVM + ABZ did they completely lose their infectivity to mice. This occurred after only 10 days post-incubation. Cellular alterations were also more marked with IVM+ABZ incubations with: (1) the presence of residual bodies, (2) numerous lipids droplets and (3) vacuoles in the cytoplasm of cytons. However, the truncated microtriches and the nuclei remained unaltered after 10 days.

Relationship between the efficacy of praziquantel treatment and the cystic differentiation in vivo of Echinococcus granulosus metacestode

The cyst differentiation of protoscolices inoculated in NMRI mice was studied in detail. Although the laminated layer began its formation at 21 days post-infection (p.i.), we could not identify this structure in all parasites until 34 days p.i.. At 34 days p.i., all protoscolices were transformed into the metacestode stage. Subsequently, the efficacy of praziquantel (PZ) was studied in different stages of development of the parasite. We have found a different PZ susceptibility in both earlier stages and well-developed cyst. PZ treatment exhibited a high efficacy at the beginning of cyst differentiation and a zero efficacy in the mature metacestode when the cystic layers were totally developed. The relationship between the tegumental ultrastructural changes occurring during the vesicular evolution of protoscolices in NMRI mice and the efficacy of PZ treatment is discussed in the present study.

Combined praziquantel and albendazole chemoprophylaxis in experimental hydatidosis

The results of the chemoprophylaxis of experimental hydatidosis with a combination of praziquantel and albendazole are presented. In vivo studies were performed on NMRI mice injected with protoscolices of Echinococcus granulosus. The treatment was the same as that previously used by us, but reducing the treatment period to only 1 month. Four months after injection , the mice were killed and autopsied. Developed hydatid cysts were counted, weighed and processed for observation by transmission electron microscopy. The efficacy of the present treatment was 97.7% and 97.15%, in number and weight of the cysts respectively, only slightly lower than that obtained by us after 4 months of treatment. Moreover, the few cysts that had developed in the treated mice showed severe damage to their ultrastructure.

Cholelithiasic disease and associated factors in a Spanish population

In order to analyze the factors associated with cholelithiasic disease, 1268 participants of a population sample were studied. On univariate analysis, 11 of the 23 variables included showed a statistically significant association (P < 0.05). Five of these variables, including obesity, triglyceride level, intake of hypolipidemic drugs, and a diet rich in cholesterol and saturated fats in women, and physical exercise in men, remained significantly associated after controlling for age. On multivariate analysis among women, a positive association was found with age (P < 0.001), obesity, and the use of hypolipidemic agents (P < 0.05) and a negative one with a diet rich in cholesterol and saturated fats (P < 0.05). Among men, the same analysis revealed there was a positive association with age (P < 0.001) and triglycerides (P < 0.05) and a negative one with physical exercise (P < 0.05). In conclusion, obesity and the use of hypolipidemic agents in women and triglycerides in men, were positively associated with cholelithiasic disease, independent of age, while negative associations included the intake of cholesterol and saturated fats in women and physical exercise in men.

Chemoprophylactic praziquantel treatment in experimental hydatidosis

In the present study, new data on the chemoprophylactic treatment of experimental hydatid disease with praziquantel are presented. In vivo studies have been performed reducing the treatment to 1 and 2 months. NMRI female mice inoculated with protoscolices of Echinococcus granulosus were treated with praziquantel 48 h p.i. at a dose of 600 mg/kg, 5 days a week for 1 or 2 months. After 4 months p.i. the animals were killed, and the cysts obtained were counted, weighed and processed for observations by means of transmission electron microscopy. Both wet weight and number of hyaline cysts found in treated mice were significantly lower than those found in control groups in both experiments (1 and 2 months of treatment), obtaining a high efficacy in all cases. Moreover, severe ultrastructural damage in the treated cysts was seen compared to the control cysts. The reduction in treatment time lays the basis for an important advance in the control and prevention of hydatidosis.

16α,17α-Epoxy-20-oxopregn-5-en-3β-yl acetate

The title compound, C23H32O4, has a 3beta configuration, with the epoxy O atom at 16alpha,17alpha. Rings A and C have slightly distorted chair conformations. Because of the presence of the C5=C6 double bond, ring B assumes an 8beta,9alpha-half-chair conformation slightly distorted towards an 8beta-sofa. Ring D has a conformation close to a 14alpha-envelope. The acetoxy and acetyl substituents are twisted with respect to the average molecular plane of the steroid. The conformation of the molecule is compared with that given by a quantum chemistry calculation using the RHF-AM1 (RHF = Roothaan Hartree-Fock) Hamiltonian model. Cohesion of the crystal can be attributed to van der Waals interactions and weak intermolecular C-H.O interactions, which link the molecules head-to-tail along [101].

Validation of a monoclonal enzyme immunoassay for the determination of carbofuran in fruits and vegetables

The N-methylcarbamate pesticide carbofuran is a very important insecticide used worldwide. In the present work, the validation of a monoclonal antibody-based enzyme immunoassay (ELISA) to determine this compound in fruits and vegetables is described. The immunoassay is a competitive heterologous ELISA in the antibody-coated format, with an I(50) value for standards in buffer of 740 ng/L and with a dynamic range between 200 and 3100 ng/L. For recovery studies, peppers, cucumbers, strawberries, tomatoes, potatoes, oranges, and apples were spiked with carbofuran at 10, 50, and 200 ppb. After liquid extraction, analyses were performed by ELISA on extracts purified on solid-phase extraction (SPE) columns and crude, nonpurified extracts. Depending on the crop, mean recoveries in the 43.9--90.7% range were obtained for purified samples and in the 90.1--121.6% range for crude extracts. The carbofuran immunoassay performance was further validated with respect to high-performance liquid chromatography (HPLC) with postcolumn derivatization and fluorescence detection (EPA Method 531.1). Samples were spiked with carbofuran at several concentrations and analyzed as blind samples by ELISA and HPLC after SPE cleanup. The correlation between methods was very good (y = 0.90x + 2.66, r(2)() = 0.958, n = 25), with HPLC being more precise than ELISA (mean coefficients of variation of 4.1 and 11.5%, respectively). The immunoassay was then applied to the analysis of nonpurified extracts of the same samples. Results also compared very well with those obtained by HPLC on purified samples (y = 1.02x + 10.44, r(2)() = 0.933, n = 29). Therefore, the developed immunoassay is a suitable method for the quantitative and reliable determination of carbofuran in fruits and vegetables even without sample cleanup, which saves time and money and considerably increases the sample throughput.