Identification of a tachykinin-related peptide with orexigenic properties in the German cockroach

A number of evidences suggest that tachykinin-related peptides (TRPs) of insects can stimulate food consumption after being released from the midgut to the hemolymph. The idea of the present work has been to test this hypothesis in the anautogenous cockroach Blattella germanica. First, we have identified the peptide LemTRP-1 (APSGFLGVR-NH2) from brain extracts, by means of an ELISA developed with a polyclonal antibody against this peptide. ELISA studies have also shown that, whereas brain LemTRP-1 levels were fairly constant, midgut levels increase to a maximum on day 3 after adult emergence, falling thereafter until the end of the gonadotrophic cycle. Interestingly, maximum values of food consumption are concomitant with the decrease of LemTRP-1 immunoreactivity in the midgut. Furthermore, starvation decreases LemTRP-1 immunoreactivity in midgut, whereas in the hemolymph it increases. Finally, injection of synthetic LemTRP-1 to adult females significantly stimulates food consumption. The whole observations suggest that LemTRP-1 is released from the midgut to the hemolymph when sustained food consumption is required to maintain vitellogenesis at the highest levels, and that LemTRP-1 in the hemolymph stimulates food consumption in these days. © 2007 Elsevier Inc. All rights reserved.Financial support from the Spanish Ministry of Science and Technology (projects AGL2002-01169 and AGL2005-00773 (X.B.) and BFU2006-01090 (J.L.M.)) and the Generalitat de Catalunya (2005 SGR 00053) are gratefully acknowledged.Peer Reviewe

Detection of pathogenic Bacteria by Electrochemical Impedance Spectroscopy: Influence of the immobilization strategies on the sensor performance

Electrochemical impedance spectroscopy (EIS) is applied to detect pathogenic E. coli O157:H7 bacteria via a label free immunoassay-based detection method. Polyclonal anti-E.coli antibodies (PAb) are immobilized onto gold electrodes following two different strategies, via chemical bond formation between antibody amino groups and a carboxylic acid containing self-assembled molecular monolayer (SAM) and alternatively by linking a biotinylated anti-E. coli to Neutravidin on a mixed-SAM. Impedance spectra for sensors of both designs for increasing concentrations of E. coli are recorded in phosphate buffered saline (PBS). The Nyquist plots can be modeled with a Randle equivalent circuit, identifying the charge transfer resistance RCT as the relevant concentration dependent parameter. Sensors fabricated from both designs are able to detect very low concentration of E. coli with limits of detection as low as 10-100 cfu/ml. The influence of the different immobilization protocols on the sensor performance is evaluated in terms of sensitivity, dynamic range and resistance against nonspecific absorption

Family physician and endocrinologist coordination as the basis for diabetes care in clinical practice

<p>Abstract</p> <p>Background</p> <p>To estimate the proportion of diabetic patients (DPts) with peripheral vascular disease treated at a primary health care site after an endocrinologist-based intervention, who meet ATP III and Steno targets of metabolic control, as well as to compare the outcome with the results of the patients treated by endocrinologists.</p> <p>Methods</p> <p>A controlled, prospective over 30-months period study was conducted in area 7 of Madrid. One hundred twenty six eligible diabetic patients diagnosed as having peripheral vascular disease between January 2003 and June 2004 were included in the study. After a treatment period of three months by the Diabetes team at St Carlos Hospital, 63 patients were randomly assigned to continue their follow up by diabetes team (Group A) and other 63 to be treated by the family physicians (FP) at primary care level with continuous diabetes team coordination (Group B). 57 DPts from Group A and 59 from Group B, completed the 30 months follow-up period. At baseline both groups were similar in age, weight, time from diagnosis and metabolic control. The main outcomes of this study were the proportion of patients meeting ATP III and Steno goals for HbA1c (%), Cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, blood pressure, albumine-to-creatinine excretion ratio (ACR), body mass index (BMI), waist circumference (WC), anti-aggregation treatment and smoking status.</p> <p>Results</p> <p>At the end of the follow up, no differences were found between the groups. More than 37% of diabetic patients assigned to be treated by FP achieved a HbA1c < 6.5%, more than 50% a ACR < 30 mg/g, and more than 80% reached low risk values for cholesterol, LDL cholesterol, triglycerides, diastolic blood pressure and were anti-aggregated, and 12% remained smokers. In contrast, less than 45% achieved a systolic blood pressure < 130 mm Hg, less than 12% had a BMI < 25 Kg.m-2 (versus 23% in group A; p < 0.05) and 49%/30% (men/women) had a waist circumference of low risk.</p> <p>Conclusion</p> <p>Improvements in metabolic control among diabetic patients with peripheral vascular disease treated at a primary health care setting is possible, reaching similar results to the patients treated at a specialized level. Despite such an improvement, body weight control remains more than poor in both levels, mainly at primary care level. General practitioner and endocrinologist coordination care may be important to enhance diabetes management in primary care settings.</p> <p>Trial registration</p> <p>Clinical Trial number ISRCTN75037597</p

Juvenile hormone and allatostatins in the German cockroach embryo

6 páginas, 4 figuras.Levels of juvenile hormone III (JH), FGLamide allatostatin peptides (ASTs), ASTs precursor (preproAST) mRNA and methyl farnesoate epoxidase (CYP15A1) mRNA were measured in embryos of the cockroach Blattella germanica. JH starts to rise just after dorsal closure, reaches maximal levels between 60% and 80% of embryogenesis, and decrease subsequently to undetectable levels. ASTs show low levels during the first two thirds of embryogenesis, increase thereafter and maintain high levels until hatching. PreproAST mRNA shows quite high levels during the two days following oviposition, thus behaving as a maternal transcript, the levels then become very low until mid embryogenesis, and increase afterwards, peaking towards the end of embryo development. CYP15A1 transcripts were detected around 25% embryogenesis and the levels tended to increase through embryogenesis, although differences amongst the days studied were not statistically significant. The opposite patterns of JH and AST towards the end of embryo development, along with the detection of AST immunoreactivity in corpora allata from late embryos, suggest that JH decline is caused by the increase of AST. Moreover, the uncorrelated patterns of JH concentration and CYP15A1 mRNA levels suggest that CYP15A1 expression does not modulate JH production.This work was supported by the Spanish Ministry of Education and Science through the projects BFU2006-01090/BFI (to J.L.M.) and CGL2008-03517/BOS (to X.B.), and by the Rector of the University of Salzburg (Austria).Peer reviewe

Peptides derived from S. aureus peptidoglycan and use thereof as haptens in a detection method

[ES] Compuestos y sus usos como haptenos para la detección S. aureus. La presente invención se refiere a compuestos derivados de la pared bacteriana de Staphylococcus aureus para su uso como haptenos, a sus aplicaciones y métodos para la detección de S. aureus, así como a los anticuerpos y antisueros generados para su utilización.[EN] The invention relates to compounds derived from the bacterial wall of Staphylococcus aureus for use as haptens, to applications and methods thereof for detecting S. aureus, and to the antibodies and antisera generated for use.Peer reviewedConsejo Superior de Investigaciones Científicas (España), Centro de Investigación Biomedica en Red (CIBER)B1 Patente sin examen previ

Compuestos y sus usos como haptenos para la detección S. aureus

[EN] The invention relates to compounds derived from the bacterial wall of Staphylococcus aureus for use as haptens, to applications and methods thereof for detecting S. aureus, and to the antibodies and antisera generated for use.[ES] Compuestos y sus usos como haptenos para la detección S. aureus. La presente invención se refiere a compuestos derivados de la pared bacteriana de Staphylococcus aureus para su uso como haptenos, a sus aplicaciones y métodos para la detección de S. aureus, así como a los anticuerpos y antisueros generados para su utilización.Peer reviewedConsejo Superior de Investigaciones Científicas (España), Centro de Investigación Biomedica en Red (CIBER)A1 Solicitud de patente con informe sobre el estado de la técnic

Peptides derived from S. aureus peptidoglycan and use thereof as haptens in a detection method

[ES] Compuestos y sus usos como haptenos para la detección S. aureus. La presente invención se refiere a compuestos derivados de la pared bacteriana de Staphylococcus aureus para su uso como haptenos, a sus aplicaciones y métodos para la detección de S. aureus, así como a los anticuerpos y antisueros generados para su utilización.[EN] The invention relates to compounds derived from the bacterial wall of Staphylococcus aureus for use as haptens, to applications and methods thereof for detecting S. aureus, and to the antibodies and antisera generated for use.Peer reviewedConsejo Superior de Investigaciones Científicas (España), Centro de Investigación Biomedica en Red (CIBER)A1 Solicitud de patente con informe sobre el estado de la técnic

Automated Multiplexed Electrochemical Immunosensing Platform for Antibiotic Residue Analysis in Milk Samples

Increasingly research efforts are focused on the development of multi-analyte residue analysis using portable devices for the on-site evaluation of foodquality, and specifically in milk. According to the directive 37/2010/EU, the EU establishes maximum residue limits (MRL) for each family of antibiotics (ATB) used in the veterinary field. The risk of ATB overuse in animals raises serious concerns for human health and the threat of antibiotic-resistant microorganisms. In this regard, we developed an automatized electrochemical platform for the multiplexed determination of the most commonly used antibiotics families in cow milk. The different immunoreagents involved in the determination of the targeted antibiotics (fluoroquinolones, streptomycin, sulfonamides and chloramphenicol) were characterized by indirect competitive enzyme-linked immunosorbent assay (ELISA). Each assay was based on the immobilization of haptenized proteins and the use of broad specificity antibodies, following a previous strategy developed by our group. Once the parameters of the assay were optimized, the matrix effect of full-fat commercial milk was assessed at different dilutions factors, ranging from 1:1 to 1:5. In all cases, the ELISAs reached a IC50 values lower than the corresponding EU MRL. Afterwards, the same immunoreagents were implemented in an automated amperometric immunosensing platform provided of gold screen-printed electrode arrays formed by eight 3-electrode electrochemical cells. The device worked using a cocktail of antibodies for the simultaneous determination of all targeted antibiotics. The LOD and IC50 values achieved are in the same range as the microplate ELISA. Matrix effect studies demonstrated that samples could be measured without any pretreatment. Moreover, a regeneration protocol was established for the consecutive measurements of real samples using the same electrodes. Altogether, our results suggest that the proposed system has a great potential for the on-site semicontinous analysis of a broad range of antibiotics residues in milk samples

Screening of antifeedant activity in brain extracts led to the identification of sulfakinin as a satiety promoter in the German cockroach. Are arthropod sulfakinins homologous to vertebrate gastrins-cholecystokinins?

7 pages, 4 figures.-- PMID: 11722569 [PubMed].-- Online version available Dec 20, 2001.The feeding cycle of the adult female cockroach Blattella germanica parallels vitellogenesis. The study of the mechanisms that regulate this cycle led us to look for food-intake inhibitors in brain extracts. The antifeedant activity of brain extracts was tested in vivo by injecting the extract and measuring the carotenoids contained in the gut from carrot ingested after the treatment. By HPLC fractionation and tracking the biological activity with the carrot test, we isolated the sulfakinin EQFDDY(SO3H) GHMRFamide (Pea-SK). A synthetic version of the peptide inhibited food intake when injected at doses of 1 microg (50% inhibition) and 10 microg (60% inhibition). The sulfate group was required for food-intake inhibition. These biological and structural features are similar to those of the gastrin-cholecystokinin (gastrin-CCK) family of vertebrate peptides. However, heterologous feeding assays (human CCK-8 tested on B. germanica, and Pea-SK tested on the goldfish Carassius auratus) were negative. In spite of this, alignment and cluster analysis of these and other structurally similar peptide families suggest that sulfakinins and gastrin-CCKs are homologous, and that mechanisms of feeding regulation involving these regulatory peptides may have been conserved during evolution between insects and vertebrates.Financial support from the Comisión Interministerial de Ciencia y Tecnología, Spain (projects 2FD97-0787 and PB98-0472) and the Generalitat de Catalunya (1999 SGR 00186) is gratefully acknowledged.Peer reviewe

DNA directed immobilization (DDI) for the development of an antibody fluorescent microarray for the determination of three family antibiotic residues in milk.

Misuse of antibiotics in food producing animals enhances the possibility to develop antibiotic resistance and can also lead to the appearance of these compounds in derivate products. New strategies to overcome this issue are required. In this context, the FoodSmartphone project will provide analytical tools to ensure food quality concerning pesticides, veterinary products or allergens, from farm to fork. The first approach is based on fluorescent microarrays which emerge as potential screening tools to determine the presence of multiple analytes at the same time. In this study, we present a multiplexed analytical platform based on hapten-oligonucleotide arrays to detect three families of antibiotics. The use of hapten-oligonucleotide conjugates allows the directed immobilization (DDI) of the signal for each antibiotic family by immobilizing the complementary oligo-probes over the surface of glass slide. After hybridization, the cocktail of primary antibodies is added in the samples and this binding is elucidated by the addition of secondary antibodies labeled to a fluorophore which provide the fluorescent signal. Using this system a group of penicillin, sulfonamides and tylosin can be quantified on buffer and milk samples. The format of this assay will provide the basis for its implementation on a Smartphone readout system