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1.
Z Rheumatol ; 80(10): 972-979, 2021 Dec.
Article in German | MEDLINE | ID: mdl-33931806

ABSTRACT

In soft tissue tumors of the extremities it is of utmost importance to differentiate between benign and malignant entities. The majority of the swellings vary from benign tissue changes through soft tissue sarcomas up to pseudotumors. Because of the low incidence of malignancy and the predominantly benign alterations together with a high heterogeneity, there is a need for a reproducible diagnostic and therapeutic concept for the treatment of all tumors of the extremities. This article reports the case of a 59-year-old patient with longstanding rheumatoid arthritis who presented to the orthopedic rheumatologic consultation with a massive swelling directly ventral to the knee joint. At that point the tumor had already grown very slowly for 5 years. The staged diagnostic process (patient history, clinical, laboratory tests, sonographic examinations, X­ray, MRI with contrast medium) revealed no trace of malignancy whatsoever. The treatment then consisted of the complete surgical excision in accordance with the recommendations for tumor surgery. Histopathological findings confirmed the diagnosis of a massive prepatellar bursitis. Initially, the extreme and solid prepatellar swelling was suspected of being malignant; however, this could already be broadly excluded preoperatively. This article presents the rationale and the orthopedic rheumatologic approach for addressing unclear space-occupying lesions of the musculoskeletal system in patients with rheumatism. In the inflammatory systemic disease in the differential diagnosis periarticular swellings can ultimately also have benign causes, such as an organized bursitis.


Subject(s)
Arthritis, Rheumatoid , Bursitis , Neoplasms , Arthritis, Rheumatoid/diagnosis , Bursitis/diagnosis , Bursitis/surgery , Humans , Knee Joint/diagnostic imaging , Knee Joint/surgery , Magnetic Resonance Imaging , Middle Aged
2.
Nat Commun ; 11(1): 1447, 2020 03 19.
Article in English | MEDLINE | ID: mdl-32193414

ABSTRACT

The de Broglie wave nature of matter is a paradigmatic example of quantum physics and it has been exploited in precision measurements of forces and fundamental constants. However, matter-wave interferometry has remained an outstanding challenge for natural polypeptides, building blocks of life, which are fragile and difficult to handle. Here, we demonstrate the wave nature of gramicidin, a natural antibiotic composed of 15 amino acids. Its center of mass is delocalized over more than 20 times the molecular size in our time-domain Talbot-Lau interferometer. We compare the observed interference fringes with a model that includes both a rigorous treatment of the peptide's quantum wave nature as well as a quantum chemical assessment of its optical properties to distinguish our result from classical predictions. The realization of quantum optics with this prototypical biomolecule paves the way for quantum-assisted measurements on a large class of biologically relevant molecules.


Subject(s)
Gramicidin/chemistry , Models, Chemical , Peptides/chemistry , Quantum Theory , Interferometry , Photons , Ultraviolet Rays
3.
Orthopade ; 47(10): 883-896, 2018 10.
Article in German | MEDLINE | ID: mdl-30132014

ABSTRACT

The management of acute pain is of utmost importance in the treatment regimen of orthopedic and trauma patients. Pain perception is different for each patient and has to be individually addressed. Especially in a postoperative setting often with a very dynamic course of pain, it is optimal that the pain management is adapted to the individual course of pain. In this situation it makes sense to apply patient-controlled systems. By combining different analgesic substance classes and non-pharmaceutical therapy in the sense of a multimodal concept, the mechanisms of action complement each other and side effects can be reduced. Patient satisfaction is higher when they are actively involved in the (medicinal) pain therapy and in the decision making. This is particularly important for patient-controlled analgesia (PCA). In addition to invasive catheter administration procedures, there are also modern approaches for oral individual self-administered opioid treatment.


Subject(s)
Acute Pain , Orthopedics , Pain Management , Wounds and Injuries , Analgesia, Patient-Controlled , Analgesics, Opioid , Humans , Pain, Postoperative , Wounds and Injuries/surgery
4.
Phys Chem Chem Phys ; 20(16): 11412-11417, 2018 Apr 25.
Article in English | MEDLINE | ID: mdl-29645042

ABSTRACT

Photocleavable tags (PCTs) have the potential for excellent spatio-temporal control over the release of subunits of complex molecules. Here, we show that electrosprayed oligopeptides, functionalized by a tailored ortho-nitroarylether can undergo site-specific photo-activated cleavage under UV irradiation (266 nm) in high vacuum. The comparison of UV photodissociation (UVPD) and collision-induced dissociation (CID) points to the thermal nature of the cleavage mechanism, a picture corroborated by the temperature dependence of the process. Two competing photodissociation pathways can be identified. In one case a phenolate anion is separated from a neutral zwitterion. In the other case a neutral phenol derivative leaves a negatively charged peptide behind. To understand the factors favoring one channel over the other, we investigate the influence of the peptide length, the nature of the phenolic group and the position of the nitro-group (ortho vs. para). The observed gas phase cleavage of a para-nitro benzylic ether markedly differs from the established behavior in solution.


Subject(s)
Nitrobenzenes/radiation effects , Oligopeptides/radiation effects , Phenols/radiation effects , Models, Chemical , Molecular Structure , Nitrobenzenes/chemistry , Oligopeptides/chemistry , Phenols/chemistry , Quantum Theory , Spectrometry, Mass, Electrospray Ionization , Temperature , Ultraviolet Rays , Vacuum
5.
J Mass Spectrom ; 52(8): 550-556, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28608445

ABSTRACT

Amino acids are essential building blocks of life, and fluorinated derivatives have gained interest in chemistry and medicine. Modern mass spectrometry has enabled the study of oligo- and polypeptides as isolated entities in the gas phase, but predominantly as singly or even multiply charged species. While laser desorption of neutral peptides into adiabatically expanding supersonic noble gas jets is possible, UV-VIS spectroscopy, electric or magnetic deflectometry as well as quantum interferometry would profit from the possibility to prepare thermally slow molecular beams. This has typically been precluded by the fragility of the peptide bond and the fact that a peptide would rather 'fry', i.e. denature and fragment than 'fly'. Here, we explore how tailored perfluoroalkyl functionalization can reduce the intermolecular binding and thus increase the volatility of peptides and compare it to previously explored methylation, acylation and amidation of peptides. We show that this strategy is essential and enables the formation of thermal beams of intact neutral tripeptides, whereas only fragments were observed for an extensively fluoroalkyl-decorated nonapeptide. © 2017 The Authors. Journal of Mass Spectrometry Published by John Wiley & Sons Ltd.


Subject(s)
Oligopeptides/analysis , Oligopeptides/chemical synthesis , Amino Acid Sequence , Binding Sites , Fluorine , Isomerism , Mass Spectrometry , Protein Binding , Protein Conformation , Protein Stability , Volatilization
6.
Nanoscale ; 9(26): 9175-9180, 2017 Jul 06.
Article in English | MEDLINE | ID: mdl-28650054

ABSTRACT

We explore the synthesis, characterization, neutral launch and vacuum ultraviolet ionization of massive perfluorinated-alkyl-capped nanoparticles. The presence of the ligand coating in solution is corroborated by Fourier transform infrared spectroscopy (FT-IR) and the particle size distribution is analyzed by transmission electron microscopy (TEM). Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry identifies perfluoralkyl coated silver nanoparticles as the most stable species among the materials studied here. They can be launched in high vacuum using long-pulse low-power laser heating - orders of magnitude below typical thresholds for laser desorption. Energy-dispersive X-ray spectroscopy (EDX) of the recaptured silver clusters confirms the expected elemental distribution. Volatilization with subsequent ionization of the neutral nanoparticle beam in high vacuum by 157 nm light allows analyzing their mass with atomic resolution.

8.
Nat Commun ; 6: 7336, 2015 Jun 11.
Article in English | MEDLINE | ID: mdl-26066053

ABSTRACT

Matter-wave interferometry can be used to probe the foundations of physics and to enable precise measurements of particle properties and fundamental constants. It relies on beam splitters that coherently divide the wave function. In atom interferometers, such elements are often realised using lasers by exploiting the dipole interaction or through photon absorption. It is intriguing to extend these ideas to complex molecules where the energy of an absorbed photon can rapidly be redistributed across many internal degrees of freedom. Here, we provide evidence that center-of-mass coherence can be maintained even when the internal energy and entropy of the interfering particle are substantially increased by absorption of photons from a standing light wave. Each photon correlates the molecular center-of-mass wave function with its internal temperature and splits it into a superposition with opposite momenta in addition to the beam-splitting action of the optical dipole potential.

9.
Genet Mol Res ; 14(4): 19110-6, 2015 Dec 29.
Article in English | MEDLINE | ID: mdl-26782563

ABSTRACT

The aim of the current study was to investigate the association between the InDel polymorphism in the angiotensin I-converting enzyme gene (ACE) and the rs699 polymorphism in the angiotensinogen gene (AGT) and diabetes mellitus type 2 (DM2) in a sample population from Southern Brazil. A case-control study was conducted with 228 patients with DM2 and 183 controls without DM2. The ACE InDel polymorphism was genotyped by polymerase chain reaction (PCR) with specific primers, followed by electrophoresis on 1.5% agarose gel. The AGT rs699 polymorphism was genotyped using a real-time PCR assay. No significant association between the ACE InDel polymorphism and DM2 was detected (P = 0.97). However, regarding the AGT rs699 polymorphism, DM2 patients had a significantly higher frequency of the AG genotype and lower frequency of the GG genotype when compared to the controls (P = 0.03). Our results suggest that there is an association between the AGT rs699 polymorphism and DM2 in a Brazilian sample.


Subject(s)
Angiotensinogen/genetics , Diabetes Mellitus, Type 2/genetics , Genetic Predisposition to Disease , INDEL Mutation , Peptidyl-Dipeptidase A/genetics , Polymorphism, Genetic , Aged , Alleles , Angiotensinogen/metabolism , Brazil , Case-Control Studies , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/pathology , Female , Gene Expression , Gene Frequency , Humans , Male , Middle Aged , Peptidyl-Dipeptidase A/metabolism , Renin-Angiotensin System/genetics , Risk Factors
10.
J Perinatol ; 34(6): 441-8, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24603455

ABSTRACT

OBJECTIVE: This prospective observational study explored the association of hypertensive disorders of pregnancy and small-for-gestational age with obstructive sleep apnea (OSA) as determined by screening measures for OSA and sleep studies. STUDY DESIGN: Two symptom-based screening questionnaires, the Berlin Questionnaire (BQ) and the Epworth Sleepiness Scale (ESS), were administered to enroll 1509 gravidae. Screen-positive subjects were referred for polysomnography. The primary outcome was the occurrence of either gestational hypertension or preeclampsia. Generalized linear models (GLM) were used to estimate the relative risks of associations. RESULT: One thousand one hundred and fifty-seven subjects were available for outcomes analysis. Screening positive on the BQ was positively associated with hypertensive disorders in GLM models (adjusted relative risk=1.90, 95% confidence interval 1.52 to 2.37). CONCLUSION: In this large prospective trial, GLM modeling suggests that the BQ but not the ESS demonstrated significant association with measured adverse pregnancy outcomes, and specific items predicted these outcomes better than others. However, causative association of BQ with OSA cannot be assumed.


Subject(s)
Hypertension, Pregnancy-Induced/diagnosis , Infant, Small for Gestational Age , Pre-Eclampsia/diagnosis , Pregnancy Outcome , Sleep Apnea, Obstructive/diagnosis , Adult , Female , Humans , Mass Screening , Middle Aged , Polysomnography , Pregnancy , Prospective Studies , Risk Assessment , Risk Factors , Surveys and Questionnaires , Young Adult
11.
J Perinatol ; 34(8): 587-93, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24674980

ABSTRACT

OBJECTIVE: We sought to ascertain the validity of two screening scales for obstructive sleep apnea (OSA) in pregnancy and to establish the prevalence of OSA in pregnancy. STUDY DESIGN: In this prospective observational study, two screening scales were administered. Screen positive subjects were referred for diagnostic polysomnography (PSG); if admitted for antepartum care, screen positive subjects underwent a modified study with a type 3 device (T3D). RESULT: A total of 1509 subjects underwent OSA screening; 58 completed diagnostic testing. Neither measure was a reliable diagnostic tool for OSA as determined by T3D or PSG (detection rates of 10.3% and 18.0%, respectively). Among screen positive subjects undergoing PSG or T3D testing, 15.5% ultimately met 'gold standard' OSA diagnostic criteria for an estimated point prevalence of 4.9%. CONCLUSION: In this prospective trial, screening positive on the Berlin questionnaire or Epworth sleepiness scale was poorly predictive of OSA among gravidae and was associated with a high false referral rate.


Subject(s)
Pregnancy Complications/diagnosis , Pregnancy Complications/epidemiology , Sleep Apnea, Obstructive/diagnosis , Sleep Apnea, Obstructive/epidemiology , Adult , Female , Humans , Polysomnography , Predictive Value of Tests , Pregnancy , Prevalence , Prospective Studies , Referral and Consultation , Reproducibility of Results , Surveys and Questionnaires , Young Adult
12.
Anal Bioanal Chem ; 405(22): 7133-44, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23831753

ABSTRACT

In this work, a novel evaluation strategy for the X-ray photoelectron spectroscopy (XPS) chemical assessment is proposed to identify the corrosion products formed on the surface of hot-dip galvanized ZnMgAl coatings after exposure to standardized salt spray tests. The experiments demonstrate that the investigated system exhibits a problematic differential charging behavior between the different compounds, an effect which cannot be fully compensated for by the flood gun of the XPS system, making a reliable evaluation of the individual spectra impossible by using standard evaluation and fitting methods. For that reason, a new effective approach--taking the different charge shifts into account--was implemented and its reliability experimentally verified on model mixtures of assumed corrosion products with known composition. With this new approach, the chemical surface composition of an industrial sample of a corroded ZnMgAl coating was revealed and discussed in order to clearly demonstrate the potential of the proposed method for future corrosion studies.

13.
Anal Bioanal Chem ; 405(22): 7119-32, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23404132

ABSTRACT

Second generation advanced high strength steel is one promising material of choice for modern automotive structural parts because of its outstanding maximal elongation and tensile strength. Nonetheless there is still a lack of corrosion protection for this material due to the fact that cost efficient hot dip galvanizing cannot be applied. The reason for the insufficient coatability with zinc is found in the segregation of manganese to the surface during annealing and the formation of manganese oxides prior coating. This work analyses the structure and chemical composition of the surface oxides on so called nano-TWIP (twinning induced plasticity) steel on the nanoscopic scale after hot dip galvanizing in a simulator with employed analytical methods comprising scanning Auger electron spectroscopy (SAES), energy dispersive X-ray spectroscopy (EDX), and focused ion beam (FIB) for cross section preparation. By the combination of these methods, it was possible to obtain detailed chemical images serving a better understanding which processes exactly occur on the surface of this novel kind of steel and how to promote in the future for this material system galvanic protection.

14.
Anal Bioanal Chem ; 403(3): 663-73, 2012 May.
Article in English | MEDLINE | ID: mdl-22362274

ABSTRACT

Zn-Cr alloyed coatings electrochemically deposited are of high interest for leading steel manufacturing companies because of their novel properties and high corrosion resistance compared with conventional Zn coatings on steel. For tuning and optimizing the properties of the electrodeposited Zn-Cr coatings, a broad range of the deposition conditions must be studied. For this reason, two different types of material were investigated in this study, one with a low electrolyte temperature and one with an elevated electrolyte pH, compared with the standard values. Because different corrosion performance and delamination behaviour of the layers were observed for the two types, advanced surface analysis was conducted to understand the origin of this behaviour and to discover differences in the formation of the coatings. The topmost surface, the shallow subsurface region, and the whole bulk down to the coating-steel interface surface were analysed in detail by X-ray photoelectron spectroscopy (XPS) and high-resolution scanning Auger electron spectroscopy to determine the elemental and the chemical composition. For better understanding of the resulting layer structure, multiple reference samples and materials were measured and their Auger and XPS spectra were fitted to the experimental data. The results showed that one coating type is composed of metallic Zn and Cr, with oxide residing only on the surface and interface, whereas the other type contains significant amounts of Zn and Cr oxides throughout the whole coating thickness.

15.
Anal Bioanal Chem ; 403(3): 651-61, 2012 May.
Article in English | MEDLINE | ID: mdl-22086398

ABSTRACT

In this work, the first few nanometres of the surface of ZnMgAl hot-dip-galvanised steel sheets were analysed by scanning Auger electron spectroscopy, angle-resolved X-ray photoelectron spectroscopy and atomic force microscopy. Although the ZnMgAl coating itself is exhibiting a complex micro-structure composed of several different phases, it is shown that the topmost surface is covered by a smooth, homogeneous oxide layer consisting of a mixture of magnesium oxide and aluminium oxide, exhibiting a higher amount of magnesium than aluminium and a total film thickness of 4.5 to 5 nm. Especially by the combined analytical approach of surface-sensitive methods, it is directly demonstrated for the first time that within surface imprints--created by industrial skin rolling of the steel sheet which ensures a smooth surface appearance as well as reduced yield-point phenomenon--the original, smooth oxide layer is partly removed and that a layer of native oxides, exactly corresponding to the chemical structure of the underlying metal phases, is formed.

16.
Appl Radiat Isot ; 69(6): 834-43, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21388817

ABSTRACT

This paper describes the development of methods for the rapid screening of gross alpha (GA) and gross beta (GB) radioactivity in liquid foods, specifically, Tang drink mix, apple juice, and milk, as well as screening of GA, GB, and gamma radioactivity from surface deposition on apples. Detailed procedures were developed for spiking of matrices with (241)Am (alpha radioactivity), (90)Sr/(90)Y (beta radioactivity), and (60)Co, (137)Cs, and (241)Am (gamma radioactivity). Matrix stability studies were performed for 43 days after spiking. The method for liquid foods is based upon rapid digestion, evaporation, and flaming, followed by gas proportional (GP) counting. For the apple matrix, surface radioactivity was acid-leached, followed by GP counting and/or gamma spectrometry. The average leaching recoveries from four different apple brands were between 63% and 96%, and have been interpreted on the basis of ion transport through the apple cuticle. The minimum detectable concentrations (MDCs) were calculated from either the background or method-blank (MB) measurements. They were found to satisfy the required U.S. FDA's Derived Intervention Levels (DILs) in all but one case. The newly developed methods can perform radioactivity screening in foods within a few hours and have the potential to capacity with further automation. They are especially applicable to emergency response following accidental or intentional contamination of food with radioactivity.


Subject(s)
Alpha Particles , Analytic Sample Preparation Methods/methods , Food Contamination, Radioactive/analysis , Gamma Rays , Malus/chemistry , Radioisotopes/analysis , Radioisotopes/chemistry , Beverages/analysis , Calibration , Cesium Radioisotopes/analysis , Cobalt Radioisotopes/analysis , Digestion , Emergencies , Malus/radiation effects , Radioactivity , Spectrometry, Gamma/methods , Strontium Radioisotopes/analysis , Yttrium Radioisotopes/analysis
17.
Curr Pharm Des ; 15(23): 2665-75, 2009.
Article in English | MEDLINE | ID: mdl-19689337

ABSTRACT

Ribonucleases degrade RNA, now considered an important drug target. The parent member of this protein superfamily is bovine pancreatic RNase A that functions as a digestive enzyme. Other physiological roles and activities have been ascribed to more recently discovered members of this superfamily. Angiogenin was isolated by following angiogenic activity from cell culture media conditioned by colon cancer cells. ONCONASE kills tumor cells in vitro and in vivo and has advanced to a phase IIIb confirmatory clinical trial for the treatment of unresectable malignant mesothelioma. All three of these RNA degrading enzymes have been used to generate immunoRNases; chemical conjugates and ligand-RNase fusion proteins, for cancer therapy. The properties of each of these RNases are described along with the increasingly sophisticated construction of recombinant immunoRNases. The advantages of using RNase as an antibody payload is compared to using plant or bacterial toxins in the construction of immunotoxins, a related strategy for specifically killing malignant cells.


Subject(s)
Antineoplastic Agents/therapeutic use , Drug Discovery/methods , Ribonucleases/therapeutic use , Animals , Humans , Immunotoxins/therapeutic use , Models, Molecular , Recombinant Proteins/biosynthesis , Recombinant Proteins/therapeutic use , Ribonuclease, Pancreatic/therapeutic use , Ribonucleases/immunology , Ribonucleases/physiology
18.
Clin Res Cardiol ; 97(11): 820-6, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18648726

ABSTRACT

AIMS: This prospective pilot-study was performed to assess whether regular moderate physical activity elevates the parasympathetic tone to the atrio-ventricular node and decreases VR during permanent AF. BACKGROUND: Adequate ventricular rate (VR) control in patients with permanent atrial fibrillation (AF) is not easy to accomplish. METHODS: 10 patients (mean age 59 +/- 10 years) with permanent AF (duration: 10 +/- 8 years) underwent moderate physical exercise adjusted to their individual physical capability (45 min walking/jogging twice a week). To analyze VR control physical exercise tests and Holter-ECG recordings were performed before and after 4 months. In addition, stepwise lactate tests and psycho-pathometric examinations were obtained. RESULTS: After 4 months of training, there was a trend toward a decrease of mean VR in 24 h Holter-ECGs by 12% from 76 +/- 20 to 67 +/- 12 bpm (P = 0.05) while there was no significant decrease of the minimal VR (38 +/- 8 vs. 36.3 +/- 4.5 bpm, P = 0.54). At a lactate threshold of 2 mmol/l there was a trend towards an increase of the running speed from 105 +/- 11 to 116 +/- 12 m/min (P = 0.05). A significant VR decrease of 8% (range 5-10%) was observed at almost all exercise levels during exercise treadmill testing. Increases of exercise capacity and decreases of VR were accompanied by subjective improvements of health perception. CONCLUSION: Regular moderate physical activity decreases VR at rest and during exercise while increasing exercise capacity. Physical training should be taken into account for ventricular rate control during AF.


Subject(s)
Atrial Fibrillation/therapy , Exercise , Heart Rate , Adolescent , Adult , Aged , Aged, 80 and over , Atrial Fibrillation/physiopathology , Electrocardiography , Exercise Test , Female , Humans , Male , Middle Aged , Patient Satisfaction , Physical Fitness , Pilot Projects , Prospective Studies , Treatment Outcome , Walking
19.
Transplant Proc ; 40(4): 981-2, 2008 May.
Article in English | MEDLINE | ID: mdl-18555095

ABSTRACT

UNLABELLED: The short cold ischemic tolerance of the gut is a major problem in small bowel transplantation. We have shown that intestinal lipid administration is beneficial during systemic inflammation like sepsis. METHODS: Rats were intestinally infused with either water or 1% olive oil for 12 hours. The small bowel was removed and stored in HTK solution on ice. At t = 0, t = 60, t = 120, t = 180, t = 240, t = 300, t = 360, t = 420, and t = 480 minutes, a tissue sample of the gut was fixed, stained, and analyzed by three independent observers. Damage score was calculated (0 = no damage, 1 = minor damage, 2 = major damage, 3 = loss of structure) for integrity of the mucosa, integrity of the basal membrane of the mucosa, and integrity of villy. The damage score was allocated when all three observers agreed on the same or a higher damage score. RESULTS: In all control animals minor damage for the integrity of the basal membrane occurred within 60 minutes, but in only 50% of the lipid-treated rats. In all control rats, major damage for both integrity of mucosa and villi occurred within 300 minutes or less, but only in 50% of the lipid-treated rats. In all control rats, the structure of the villi was completely lost within 480 minutes or less, whereas only 50% of the lipid treated animals reached maximal damage scores for either mucosa or villi. CONCLUSION: Intestinal lipid administration before cold storage clearly decreases histologic damage of the small bowel and might increase the tolerance for cold ischemia. Lipids or their metabolites stored in enterocytes may act as an antiinflammatory. Intestinal lipid administration in organ donors might be useful to increase cold ischemic tolerance of the small bowel.


Subject(s)
Intestinal Absorption , Intestine, Small/physiopathology , Ischemia/physiopathology , Lipids/physiology , Plant Oils/pharmacology , Animals , Intestinal Mucosa/drug effects , Intestine, Small/blood supply , Intestine, Small/drug effects , Male , Olive Oil , Organ Preservation Solutions , Rats , Rats, Sprague-Dawley
20.
Ecotoxicol Environ Saf ; 70(2): 334-40, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18068780

ABSTRACT

The effects of the insecticidal Cry1Ab protein from Bacillus thuringiensis (Bt) on the nematode, Caenorhabditis elegans, were studied with soil from experimental fields cultivated with transgenic Bt corn (MON810) and with trypsinized Cry1Ab protein expressed in Escherichia coli. The content of Cry1Ab protein was above the detection limit of an ELISA test in only half of the soil samples obtained from transgenic plots, ranging from 0.19 to 1.31 ng g(-1) dry weight. In a laboratory bioassay, C. elegans was exposed to rhizosphere and bulk soil from fields with isogenic or transgenic corn or to solutions of Cry1Ab protein (0, 24, 41, 63, 118, and 200 mg l(-1)) over a period of 96 h, with growth and reproduction serving as the test parameters. Nematode reproduction and growth were significantly reduced in rhizosphere and bulk soil of Bt corn compared with soil from isogenic corn and were significantly correlated with concentrations of the Cry1Ab protein in the soil samples. Moreover, the toxicity of pure Cry1Ab protein to the reproduction and growth of C. elegans was concentration-dependent. As significant inhibition occurred at relatively high concentrations of the Cry1Ab protein (41 mg l(-1)), the effects of the soil samples from Bt corn could not be assigned directly to the toxicity of the Cry1Ab protein. The results demonstrate that bioassays with the nematode, C. elegans, provide a promising tool for monitoring the potential effects of Bt toxins in aqueous medium and soils.


Subject(s)
Bacterial Proteins/toxicity , Caenorhabditis elegans/drug effects , Endotoxins/toxicity , Hemolysin Proteins/toxicity , Insecticides/toxicity , Plants, Genetically Modified , Zea mays/genetics , Animals , Bacillus thuringiensis Toxins , Bacterial Proteins/genetics , Caenorhabditis elegans/physiology , Endotoxins/genetics , Escherichia coli/genetics , Hemolysin Proteins/genetics , No-Observed-Adverse-Effect Level , Reproduction/drug effects
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