In vitro profiling of endothelial volatile organic compounds under resting and pro-inflammatory conditions.

INTRODUCTION: The evaluation of volatile organic compounds(VOCs) emitted by human body offers a unique tool to set up new non-invasive devices for early diagnosis and long-lasting monitoring of most human diseases. However, their cellular origin and metabolic fate have not been completely elucidated yet, thus limiting their clinical application. Endothelium acts as an interface between blood and surrounding tissues. As such, it adapts its physiology in response to different environmental modifications thus playing a role in the pathogenesis of many metabolic and inflammatory diseases. OBJECTIVES: Since endothelium specifically reshapes its physiologic functions upon environmental changes the objective of this study was to evaluate if and how pro-inflammatory stimuli affect VOC metabolism in endothelial cell in culture. METHODS: Gas chromatography with mass spectrometric detection was applied to profile VOCs in the headspace of cultured endothelial cells (EC) in the absence or presence of the pro-inflammatory stimulus lipopolysaccharide (LPS). RESULTS: We observed that, under resting conditions, EC affected the amount of 58 VOCs belonging to aldehyde, alkane and ketone families. Among these, LPS significantly altered the amount of 15 VOCs. ROC curves show a perfect performance (AUC = 1) for 10 metabolites including 1-butanol, 3-methyl-1-butanol and 2-ethyl-1-hexanol. DISCUSSION: The emission and uptake of the aforementioned VOCs disclose potential unexplored metabolic pathways for EC that deserve to be investigated. Overall, we identified new candidate VOC potentially exploitable, upon experimental confirm in in vivo model of disease, as potential biomarkers of sepsis and pro-inflammatory clinical settings.

Fe3O4/γ-Fe2O3 nanoparticle multilayers deposited by the Langmuir-Blodgett technique for gas sensors application.

Fe3O4/γ-Fe2O3 nanoparticles (NPs) based thin films were used as active layers in solid state resistive chemical sensors. NPs were synthesized by high temperature solution phase reaction. Sensing NP monolayers (ML) were deposited by Langmuir-Blodgett (LB) techniques onto chemoresistive transduction platforms. The sensing ML were UV treated to remove NP insulating capping. Sensors surface was characterized by scanning electron microscopy (SEM). Systematic gas sensing tests in controlled atmosphere were carried out toward NO2, CO, and acetone at different concentrations and working temperatures of the sensing layers. The best sensing performance results were obtained for sensors with higher NPs coverage (10 ML), mainly for NO2 gas showing interesting selectivity toward nitrogen oxides. Electrical properties and conduction mechanisms are discussed.

Label-free electrochemical biosensor for direct detection of Oncostatin M (OSM) inflammatory bowel diseases (IBD) biomarker in human serum.

Oncostatin M (OSM) is an interleukin-6 (IL-6) member family cytokine implicated in the pathogenesis of chronic diseases including inflammatory bowel disease (IBD). OSM is a novel diagnostic biomarker over-expressed in the serum of IBD patients. This paper reports on the first electrochemical OSM immunosensor, developed using a multistep fabrication process aimed at covalently immobilizing OSM antibodies on a mixed self-assembled monolayer coated gold working electrode. Cyclic voltammetry, atomic force microscopy (AFM), IR spectroscopy and optical characterizations were used to validate the sensor functionalization protocol. Electrochemical impedance spectroscopy (EIS) measurements were performed to assess the reliability of the immunosensor preparation and to verify the antibody-antigen complexes formation. The label-free immunosensor showed high sensitivity identifying OSM at clinically relevant concentrations (37-1000 pg mL-1) with low detection limit of 2.86 pg mL-1. Both sensitivity and selectivity of the proposed immunosensor were also demonstrated in human serum in the presence of interfering biomarkers, making it an innovative potential platform for the OSM biomarker detection in IBD patients' serum.

Effect of top-down nanomachining on electrical conduction properties of TiO2 nanostructure-based chemical sensors.

The present research was motivated by the growing interest of the scientific community towards the understanding of basic gas-surface interaction mechanisms in 1D nanostructured metal oxide semiconductors, whose significantly enhanced chemical detection sensitivity is known. In this work, impedance spectroscopy (IS) was used to evaluate how a top-down patterning of the sensitive layer can modulate the electrical properties of a gas sensor based on a fully integrated nanometric array of TiO(2) polycrystalline strips. The aim of the study was supported by comparative experimental activity carried out on different thin film gas sensors based on identical TiO(2) polycrystalline sensitive thin films. The impedance responses of the investigated devices under dry air (as the reference environment) and ethanol vapors (as the target gas) were fitted by a complex nonlinear least-squares method using LEVM software, in order to find an appropriate equivalent circuit describing the main conduction processes involved in the gas/semiconductor interactions. Two different equivalent circuit models were identified as completely representative of the TiO(2) thin film and the TiO(2) nanostructure-based gas sensors, respectively. All the circuit parameters were quantified and the related standard deviations were evaluated. The simulated results well approximated the experimental data as indicated by the small mean errors of the fits (in the range of 10(-4)) and the small standard deviations of the circuit parameters. In addition to the substrate capacitance, three different contributions to the overall conduction mechanism were identified for both equivalent circuits: bulk conductivity, intergrain contact and semiconductor-electrode contact, electrically represented by an ideal resistor R(g), a parallel R(gb)C(gb) block and a parallel R(c)-CPE(c) combination, respectively. In terms of equivalent circuit modeling, the sensitive layer patterning introduced an additional parameter in parallel connection with the whole circuit block. Such a circuit element (an ideal inductor, L) has an average value of about 125 µH and exhibits no direct dependence on the analyte gas concentration. Its presence could be due to complex mutual inductance effects occurring both between all the adjacent nanostrips (10 µm spaced) and between the nanostrips and the n-type-doped silicon substrate underneath the thermal oxide (wire/plate effect), where a two order of magnitude higher magnetic permeability of silicon can give L values comparable with those estimated by the fitting procedure. Slightly modified experimental models confirmed that the theoretical background, regulating thin film devices based on metal oxide semiconductors, is also valid for nanopatterned devices.

Safe and fit genetically modified insects for pest control: from lab to field applications.

Insect transgenesis is continuously being improved to increase the efficacy of population suppression and replacement strategies directed to the control of insect species of economic and sanitary interest. An essential prerequisite for the success of both pest control applications is that the fitness of the transformant individuals is not impaired, so that, once released in the field, they can efficiently compete with or even out-compete their wild-type counterparts for matings in order to reduce the population size, or to spread desirable genes into the target population. Recent research has shown that the production of fit and competitive transformants can now be achieved and that transgenes may not necessarily confer a fitness cost. In this article we review the most recent published results of the fitness assessment of different transgenic insect lines and underline the necessity to fulfill key requirements of ecological safety. Fitness evaluation studies performed in field cages and medium/large-scale rearing will validate the present encouraging laboratory results, giving an indication of the performance of the transgenic insect genotype after release in pest control programmes.

Effect of dietary boron on immune function in growing beef steers.

Thirty-six Angus and Angus x Simmental cross steers (initial BW 269.5 +/- 22.3 kg) were used to determine the effects of dietary boron (B) on performance and immune function. Steers were fed on one of the three dietary treatments: (i) control (no supplemental B; 7.2 mg B/kg DM), (ii) 5 mg supplemental B/kg DM and (iii) 50 mg supplemental B/kg DM, from sodium borate for 78 days. Supplementation of dietary B had no effect on body weight (BW) gain, feed intake or gain:feed during the study. Jugular blood samples were collected prior to feeding on days 28, 63 and 77 for plasma-B analysis. Supplementation of dietary B increased (p < 0.001) plasma B-concentration in a dose-responsive manner. Furthermore, plasma B-concentration was correlated (p < 0.001; R(2) = 0. 95) to daily B-intake (mg B/day). Jugular blood was also collected, from an equal number of steers from each treatment, on day 42 or 44 for determination of in vitro production of interferon-gamma and tumour necrosis factor-alpha from isolated monocytes and assessment of lymphocyte proliferation. Dietary B did not affect T- or B-lymphocyte proliferation or in vitro cytokine production from monocytes. On day 49 of the study, the humoral immune response was assessed by i.m. injection of a 25% pig red blood cell (PRBC) solution for determination of anti-PRBC IgG and IgM titre responses. Boron-supplemented steers had greater (p = 0.035) anti-PRBC IgG titres than controls on day 7 but not on day 14 or 21 post-injection. Anti-PRBC IgM titres did not differ throughout the sampling period. Results from this study indicate that supplemental B had minimal effects on immune function and did not affect performance of growing steers.

Uncovering the tracks of a recent and rapid invasion: the case of the fruit fly pest Bactrocera invadens (Diptera: Tephritidae) in Africa.

Phytophagous insects of the genus Bactrocera are among the most economically important invasive fruit fly pests. In 2003, an unknown Bactrocera species was found in Kenya. First identified as an 'aberrant form' of the Asian B. dorsalis complex, it was later recognized as a new species, Bactrocera invadens. Within 2 years of its discovery, the species was recorded in several African countries, becoming an important quarantine pest. As this invasive fly was discovered only recently, no data are available on its invasion pattern in Africa. This pilot study attempts to infer from genetic data the dynamic aspects of the African invasion of this pest. Using microsatellite markers, we evaluated the level of genetic diversity and the extent of common ancestry among several African populations collected across the invaded areas. A sample from the Asian Sri Lankan population was analysed to confirm the Asian origin of this pest. Genetic data cast no doubt that Sri Lanka belongs to the native range, but only a small percentage of its genotypes can be found in Africa. African populations display relatively high levels of genetic diversity associated with limited geographical structure and no genetic footprints of bottlenecks. These features are indicative of processes of rapid population growth and expansion with possible multiple introductions. In the span of relatively few years, the African invasion registered the presence of at least two uncorrelated outbreaks, both starting from the East. The results of the analyses support that invasion started in East Africa, where B. invadens was initially isolated.

Fabrication and characterization of AlN-based flexible piezoelectric pressure sensor integrated into an implantable artificial pancreas.

This study reports on the fabrication and characterization of an event detection subsystem composed of a flexible piezoelectric pressure sensor and the electronic interface to be integrated into an implantable artificial pancreas (IAP) for diabetic patients. The developed sensor is made of an AlN layer, sandwiched between two Ti electrodes, sputtered on Kapton substrate, with a preferential orientation along c-axis which guarantees the best piezoelectric response. The IAP is made of an intestinal wall-interfaced refilling module, able to dock an ingestible insulin capsule. A linearly actuated needle punches the duodenum tissue and then the PDMS capsule to transfer the insulin to an implanted reservoir. The device is located at the connection of the needle with the linear actuator to reliably detect the occurred punching of the insulin-filled capsule. Finite Element Analysis (FEA) simulations were performed to evaluate the piezoelectric charge generated for increasing loads in the range of interest, applied on both the sensor full-area and footprint area of the Hamilton needle used for the capsule punching. The sensor-interface circuit was simulated to estimate the output voltage that can be obtained in real operating conditions. The characterization results confirmed a high device sensitivity during the punching, in the low forces (0-4 N) and low actuator speed (2-3 mm/s) ranges of interest, meeting the requirement of the research objective. The choice of a piezoelectric pressure sensor is particularly strategic in the medical field due to the request of self-powered implantable devices which do not need any external power source to output a signal and harvest energy from natural sources around the patient.

Surface plamon resonance imaging of DNA based biosensors for potential applications in food analysis.

The adsorption processes of oligonucleotides immobilised onto suitable photolithographic patterned gold substrates have been investigated in aqueous buffer solution by using a home made surface plasmon resonance (SPR) imaging equipment. A rapid self-assembled method for the construction of DNA chips to be used in SPR imaging experiments have been followed. The immobilised DNA molecules (probes) adopted in our SPR experiments anchored to a gold surface via thiol group were 5'thiol-modified containing a (CH(2))(15) tail. The hybridisation processes taking place with its complementary sequence have been observed and characterized by monitoring phenomena by a SPR imaging system. The two analysed oligonucleotides (probes and target) are of interest in plant gene biotechnological application and differing for the presence at the 5'-end of a poly T16 spacer. Dynamic investigation of smallest changes in SPR imaging pictures performed in liquid phase in the presence of DNA complementary probes have been performed. Quantitative information in terms of threshold of sensitivity has been extracted by using a specific images treatment.

Liquid phase SPR imaging experiments for biosensors applications.

Surface plasmon resonance (SPR) has recently gained attention as a label-free method for the detection of biological molecules binding onto functionalised surfaces. It is one of the most sensitive detection method for monitor variations in the thickness and refractive index in ultra-thin films. Here, the adsorption processes of oligonucleotides onto gold substrates have been investigated in aqueous buffer solution using SPR imaging measurements. The hybridization of a thiol-modified, single stranded oligonucleotide anchored to a gold surface via thiol group, with its complementary sequence has been observed and characterised monitoring the hybridization process by SPR equipment. In situ investigation of smallest changes in SPR imaging measurements dynamically performed in liquid phase in the presence of DNA complementary probes was performed. Infrared spectroscopy and scanning electron microscopy characterisation of the functionalised gold surfaces of the biosensor were compared with the images obtained by SPR experimental apparatus.

Primary eosinophilic granuloma invading the skull base: case report and critical review of the literature.

A case of eosinophilic granuloma of the lesser wing of the sphenoid bone is reported. The patient was a 5-year-old white male, with left temporal-frontal headache, left III cranial nerve palsy, left exophthalmos and ptosis caused by an osteolytic lesion of the anterior clinoid process extending to the left optic canal and cavernous sinus. The patient underwent surgical resection of pathologic tissue. Pathologic diagnosis was eosinophilic granuloma of the sphenoid bone. Surgical management, postoperative prognosis and differential diagnosis of eosinophilic granuloma of the skull base are discussed along with a review of the literature.

Evidence supporting an increased presence of reactive oxygen species in the diseased equine joint.

Reactive oxygen species (ROS) are capable of degrading many components of the joint in the presence of insufficient antioxidant defences, and as a result have been implicated in the pathogenesis of joint disease in horses. However, to our knowledge, evidence of ROS occurring in diseased joints of horses has not been reported. The objective of this experiment was to compare differences in synovial fluid protein carbonyl content (as a marker of oxidative modification of synovial fluid proteins by ROS) and the antioxidant status of synovial fluid between clinically normal and diseased equine joints. Synovial fluid was collected from the metacarpophalangeal, metatarsophalangeal, carpal and tarsal joints of 4 horses, age 2-5 years, as controls, and from diseased joints (metacarpophalangeal, metatarsophalangeal, carpal, tarsal and/or femoropatellar) of 61 horses, age 2-5 years. Synovial fluid protein carbonyl content was higher (P<0.01) in diseased joints as compared to controls. Antioxidant status of synovial fluid from diseased joints was higher, but not significantly, than that of controls (P = 0.0595). These findings require further study to determine their contribution to the overall disease process.

The effect of added dietary soybean oil on vitamin E status of the horse.

Fourteen 2-yr-old Quarter Horses and Quarter Horse x Thoroughbreds were randomly assigned to either a control (CTRL) diet or a diet supplemented with 6.4% soybean oil (SBO). The amounts of both diets that were fed met current NRC nutrient requirements and were isoenergetic with similar nutrient:energy ratios. Venous blood samples (20 mL) were taken at d 0, 30, 60, and 90 of the experiment and analyzed for serum alpha-tocopherol, serum cholesterol, and serum triglyceride. The sum of serum cholesterol and serum triglyceride values was used as an estimate of serum total lipid. The ratio of serum alpha-tocopherol:serum total lipid was used as a measure of vitamin E status of horses. The SBO group had higher serum cholesterol concentrations (P < .001) at 30, 60, and 90 d. Serum triglyceride was not affected by diet. Serum total lipids tended to be greater (P < .06) for the SBO group. Serum alpha-tocopherol was greater (P < .001) at 90 d in the SBO group. There was a significant correlation (P < .001, r = .62) between serum total lipids and serum alpha-tocopherol concentrations in the SBO group. This correlation was not significant (P < .07, r = .35) in the CTRL group. The ratio of serum alpha-tocopherol:serum total lipid was not affected by diet. The results of this experiment suggest that vitamin E status in non-exercising, 2-yr-old horses fed currently recommended levels of vitamin E was not affected by the addition of 6.4% SBO to the diet.

The effect of initiation of exercise training in young horses on vitamin K status.

Twelve Quarter Horses, 18 to 24 mo of age and having an average body weight of 460+/-12 kg, were randomly assigned to one of two exercise treatments (control and exercise) to study the effect of initiation of exercise training in young horses on vitamin K status. The control treatment consisted of hand-walking the horses 7 min/d and 5 d/wk for 180 d. Exercise consisted of the following treadmill exercise regimen: 2 min at 4.5 to 5.4 m/s, 3 min at 13.4 to 14.3 m/s, and 2 min at 4.5 to 5.4 m/s on 5 d/wk for 180 d. Both groups were allowed free access to brome grass hay (273 mg of phylloquinone/100 g) individually. Additionally, the exercise group was fed .45 kg of a grain-mix concentrate (40 mg of phylloquinone/100 g) on the days they were exercised. Jugular venous blood samples were collected at d 0, 30, 60, 90, 120, 150, and 180. Blood samples were analyzed for total serum osteocalcin and vitamin K status via the hydroxyapatite binding capacity of serum osteocalcin calculated as follows: Hydroxyapatite binding capacity of serum osteocalcin = [(total serum osteocalcin - serum osteocalcin following extraction of serum with hydroxyapatite)/total serum osteocalcin] x 100. All horses were killed with an overdose of sodium pentobarbital on d 180. Computed tomographic osteoabsorptiometry was used to measure relative bone density distribution on the surface of the distal radial carpal bone, proximal third carpal bone, and the distal third metacarpal condyle. Relative bone density distribution was measured in Hounsfield units and categorized as low-, medium-, and high-density bone corresponding to 800 to 1,199, 1,200 to 1,299, and 1,300 to 3,000 Hounsfield units, respectively. Carpal and metacarpophalangeal joints were assigned a score of 0 (normal) to 3 (severe) that reflected the presence and severity of joint lesions. Hydroxyapatite binding capacity of serum osteocalcin and serum osteocalcin were unchanged over the 180-d period in both groups. Exercised horses had a higher percentage of high density bone (P < .01) and a lower percentage of low density bone (P < .01) on the surface of the third metacarpal condyle and a higher cumulative gross lesion score (P < .01) in the metacarpophalangeal joint than controls. There were no differences between treatments in relative bone density distribution in the carpal bones, or cumulative gross lesion score of the carpal joints. No significant correlation was present between the serum measures, osteocalcin and hydroxyapatite binding capacity of serum osteocalcin, and the bone measures, relative bone density distribution and joint gross lesion score.

Effect of dietary vitamin E supplementation on the integrity of skeletal muscle in exercised horses.

The effect of vitamin E intake on indicators of muscle integrity was studied in exercised horses. Nineteen horses were blocked by sex and then assigned to one of three diets: no supplemental vitamin E (BASAL), BASAL plus 80 IU of supplemental vitamin E/kg DM (80), or BASAL plus 300 IU of supplemental vitamin E/kg DM (300). The BASAL diet contained less than 44 IU of vitamin E/kg DM, but it was adequate in all other nutrients. During the 90-d treatment period, horses were exercised 5 d/wk; in addition, serum and middle gluteal muscle alpha-tocopherol concentrations were measured at 0, 30, and 90 d. All horses performed a repeated submaximal exercise test (RSET) at the end of the 90-d period. The following were measured before and after the RSET: alpha-tocopherol, thiobarbituric acid reactive substances (TBARS), conjugated diene (CD) concentrations of the middle gluteal muscle, and serum creatine kinase (CK) and aspartate aminotransferase (AST) activities. Serum alpha-tocopherol concentrations of horses receiving the BASAL and 80 diets decreased (P < .05 and P < .06, respectively) during the 90-d treatment period but did not change in horses receiving the 300 diet. Serum and muscle alpha-tocopherol concentrations were higher (P < .05) at 30 and 90 d in horses receiving the 300 diet than in horses receiving the BASAL and 80 diets. Serum CK and AST activities increased (P < .05) following RSET but were not affected by dietary vitamin E level. Muscle alpha-tocopherol level did not affect muscle CD or TBARS.

Effect of short-term feed restriction and calorie source on hormonal and metabolic responses in geldings receiving a small meal.

The metabolic effects of short-term feed restriction and dietary calorie source were studied in horses receiving high-roughage or high-concentrate diets. Four Thoroughbred geldings were assigned to four treatment groups in a 4 x 4 Latin square experiment. The four treatments were 1) a nutritionally adequate high-roughage ration (70% roughage, 30% concentrate; AHR), 2) a nutritionally adequate high-concentrate ration (40% roughage, 60% concentrate; AHC), 3) 70% of the intake of the AHR diet (RHR), and 4) 70% of the intake of the AHC diet (RHC). Diets AHR and AHC were designed to meet the caloric need of horses undergoing moderately intense work. Blood samples were taken on the first 7 d of each period for analysis of serum T4 and T3 concentrations. On d 9 of each feeding period, each horse was fed 1.0 kg of oats as the morning meal. Jugular blood was sampled before and immediately after, as well as at 30 min after, completion of the meal and subsequently every hour for 7 h. Daily serum T4 and T3 concentrations were not affected by day, feeding level, or diet composition. Meal feeding produced an increase (P < 0.01) in T4 and T3 concentrations when horses were adapted to the AHR and AHC diets but not the RHR or RHC diets. Thyroxine concentrations were lowest (P < 0.05) when horses were adapted to the AHC diet. Glucose (P < 0.05), insulin (P < 0.01), and NEFA (P < 0.01) concentrations were higher in response to the meal when horses received RHR than for the other diets. These results indicate that nutrient restriction alters responses to meal feeding in horses and that this response may also be affected by the dietary roughage:concentrate ratio.

[Reflux oesophagitis and risk factors. Results of a population study]. / Esofagite da reflusso e fattori di rischio. Risultati di uno studio di popolazione.

BACKGROUND: To evaluate the prevalence and endoscopic grade of reflux oesophagitis (RO) and to correlate them to symptoms and to a list of risk factors including age, sex, weight, smoking, alcohol, work, hiatus hernia. METHODS: This study was carried out in Roccacorga (LT), a little town of 3435 inhabitants in central Italy. The sample totalled 1084 volunteers, aged over 18 years old and enlisted in opened cohort. After filling in the questionnaire, all the patients were subjected to esophagogastroduodenoscopy without eating for at least six hours and diazepam pretreated (10 mg ev). Three biopsies were routine performed on the 3 biopsies on distal esophagous wall. The RO range was evaluated according to the Savary-Miller classification. RESULTS: The RO was found in 443 patients (188 M, 42%; 255 F, 58%) (p<0.0002), a large number of asymptomatic patients (39%). The prevalence of hiatus hernia was 7.2%, RO associated in 60.3% (p<0005). The prevalence of associated gastroduodenal injuries was pointed out (p<0.03). Patients affected only by RO were mostly female (p<0.02). Precancerous esophagous were 0,37%. CONCLUSIONS: According to this study the RO diagnosed through endoscopy is much more prevalent than supposed, especially among females and it affects a younger age than reported (31-50 years). Smoking and alcohol are among male risk factors, while, in female, agricultural works, weight and hormonal state could have a leading role (p=NS).

[Duodenal ulcer and Helicobacter pylori]. / Ulcera duodenale in epoca Helicobacter pylori.

BACKGROUND: The purpose of this study was to evaluate the relationship between duodenal ulcer (DU), Helicobacter pylori (Hp) infection and genetic and enviromental factors, and its influence on treatment and long-term RESULTS. METHOD: In the course of an epidemiological study on the prevalence of esophagogastroduodenal diseases, 1,169 volunteers underwent an endoscopy of the upper part of the gastrointestinal tract. The relationship of incidence rate and size of duodenal ulcers and several risks factors was investigated. RESULTS: A DU was observed in 240 subjects (20.5%), mostly of male gender (64.4% - p<0.0001). The Histological presence of a gastric Hp infection was confirmed in 179 cases (74.6%); it did not influenced the mean size of the ulcers and the presence of gastric intestinal metaplasia, compared to subjects without Hp infection. However, a superficial chronic gastritis was observed in 95.9% of Hp+ subjects and in 83.3% of Hp- (p<0.003), whereas a familiar history of DU was noted in 33.3% of Hp+ subjects and in 50.8% of Hp- (p<0.02). The main risk factor for DU was represented by Hp infection in 119 cases (49.6%), by infective and genetic factors in 60 cases (25%) and only by the genetic factor in 31 cases (12.9%), and was not detected in 30 cases (12.5%). Ulcer recurrence rates, after medical therapy, were 0,5% and 6.5% (p<0.03) at a 2-month follow-up, and 2.2% and 49.1% (p<0.00001) at a 12-month follow-up, among Hp+ and Hp- patients, respectively. CONCLUSIONS: The most common risk factor for DU was a gastric Hp infection, alone or associated to the genetic factor. Since the high incidence of recurrences at a 12-month follow-up, patients affected with a DU but Hp- represented an important therapeutic concern.

Intake estimation of horses grazing tall fescue (Lolium arundinaceum) or fed tall fescue hay.

Six mature geldings of light horse breeds (557 ± 37 kg) were randomly assigned to a nontoxic endophyte-infected tall fescue hay (n = 3) or pasture treatment (n = 3) in a crossover design with 14-d periods to estimate DMI with alkane markers and to compare DMI of hay and pasture. When fed pasture, horses were housed in stalls from 0700 to 1300 h daily with access to water and then grazed pasture as a group in a single 0.4 ha pasture from 1300 to 0700 h. When fed hay, horses were maintained individually in stalls and given access to hay ad libitum from 1300 to 0700 h. All horses were individually fed 225 g oats twice daily treated with hexatriacontane (C36; external marker) and fecal samples were collected at 0700 and 1900 h on d 10 to 14. Fecal samples were mixed, dried, subsampled, and analyzed for tritriacontane (C33) and hentriacontane (C31) as internal markers and C36 as the external marker using gas chromatography. Estimated hay DMI using either C33 (1.75 kg/100 kg BW) or C31 (1.74 kg/100 kg BW) as internal alkane marker did not differ (P = 0.55) from measured hay DMI (1.70 kg/100 kg BW). Pasture DMI and DM digestibility (DMD) estimated with C31 (2.24 kg/100 kg BW and 53.1 g/100 g DMI) or with C33 (2.34 kg/100 kg BW and 56.2 g/100 g DMI) was greater (P = 0.05) than hay DMI and DMD (1.74 kg/100 kg BW and 44.5 g/100 g DMI). Intake estimated with C33 or C31 did not differ (P = 0.35) during hay or pasture. In conclusion, alkanes can be used to estimate pasture or hay DMI and DMD, and pasture intake exceeded hay intake when offered ad libitum.

Identification of pheromone components and their binding affinity to the odorant binding protein CcapOBP83a-2 of the Mediterranean fruit fly, Ceratitis capitata.

The Mediterranean fruit fly (or medfly), Ceratitis capitata (Wiedemann; Diptera: Tephritidae), is a serious pest of agriculture worldwide, displaying a very wide larval host range with more than 250 different species of fruit and vegetables. Olfaction plays a key role in the invasive potential of this species. Unfortunately, the pheromone communication system of the medfly is complex and still not well established. In this study, we report the isolation of chemicals emitted by sexually mature individuals during the "calling" period and the electrophysiological responses that these compounds elicit on the antennae of male and female flies. Fifteen compounds with electrophysiological activity were isolated and identified in male emissions by gas chromatography coupled to electroantennography (GC-EAG). Within the group of 15 identified compounds, 11 elicited a response in antennae of both sexes, whilst 4 elicited a response only in female antennae. The binding affinity of these compounds, plus 4 additional compounds known to be behaviourally active from other studies, was measured using C. capitata OBP, CcapOBP83a-2. This OBP has a high homology to Drosophila melanogaster OBPs OS-E and OS-F, which are associated with trichoid sensilla and co-expressed with the well-studied Drosophila pheromone binding protein LUSH. The results provide evidence of involvement of CcapOBP83a-2 in the medfly's odorant perception and its wider specificity for (E,E)-α-farnesene, one of the five major compounds in medfly male pheromone emission. This represents the first step in the clarification of the C. capitata and pheromone reception pathway, and a starting point for further studies aimed towards the creation of new powerful attractants or repellents applicable in the actual control strategies.