Pretargeting of Carcinomas with the Avidin-Biotin System

Diagnosis and experimental therapy of cancer have been performed with encouraging results using radiolabelled monoclonal antibodies. However, the high background due to non-specific uptake by normal tissue and blood is a major drawback in antibody-guided tumor detection. Various strategies have been proposed to overcome this problem, such as computed background subtraction, use of a second antibody, and local delivery. An antibody is a slow “bullet” for tumor targeting, since in many lesions it requires two or three days to accumulate. The use of fragments such as F(ab’)2 or Fab, which display a faster blood clearance than whole antibody, improves tumor localization to a sufficient extent (hours) to allow the use of the most suitable radionuclides, e.g. 99m-Tc. In therapeutic applications we are still far away from the optimal condition in terms of the absolute amount of radioactivity delivered to the tumor. The high specificity of antibodies could be exploited at its best by delaying the delivery of the label to a time when the ratio tumor-bound to non-tumor-bound antibody has reached its maximum value. To obtain this goal, the label should display a fast clearance and should be captured by the antibody already targeted onto tumor cells. These considerations have led to strategies of tumor pretargeting where antibody and label are administered separately. One of these strategies, based on the avidin-biotin system, has already been used extensively for several years in immunohistochemistry and in ELISA. Due to the flexibility of this system, several alternative protocols are possible.

We describe a three-step and a two-step pretargeting protocol based on the avidin-biotin system.

Using Deconvolution to Improve PET Spatial Resolution in OSEM Iterative Reconstruction

Objectives : A novel approach to the PET image reconstruction is presented, based on the inclusion of image deconvolution during conventional OSEM reconstruction. Deconvolution is here used to provide a recovered PET image to be included as “a priori" information to guide OSEM toward an improved solution.

Methods : Deconvolution was implemented using the Lucy-Richardson (LR) algorithm: Two different deconvolution schemes were tested, modifying the conventional OSEM iterative formulation: 1) We built a regularizing penalty function on the recovered PET image obtained by deconvolution and included i in the OSEM iteration. 2) After each conventional global OSEM iteration, we deconvolved the resulting PET image and used this “recovered" version as the initialization image for the next OSEM iteration. Tests were performed on both simulated and acquired data.

Results : Compared to the conventional OSEM, both these strategies, applied to simulated and acquired data, showed an improvement in image spatial resolution with better behavior in the second case. In this way, small lesions, present on data, could be better discriminated in terms of contrast.

Conclusions : Application of this approach to both simulated and acquired data suggests its efficacy in obtaining PET images of enhanced quality.

Different training schedules influence platelet aggregation in show jumping horses

Depending on the intensity, duration and type of physical exercise, equine metabolism has to adapt to nervous, cardiovascular, endocrine and respiratory system requirements. In horses, exercise and training are known to have considerable effects on the mechanisms of hemostatic system involving platelet activity. The aim of the present study was to evaluate the effect of different training schedules on platelet aggregation in 15 Italian Saddle jumping horses. Animals were divided into three equal groups: Group A was subjected to a high intensity-training program; group B to a light training program, group C included sedentary horses. From each animal, blood samples were collected by jugular venipuncture at rest on the 1st, 3rd and 5th days, and afterwards, once a week, for a total of 5 weeks data recording, in order to assess the maximum degree of platelet aggregation and the initial velocity of aggregation (slope) platelet aggregation. Two-way analysis of variance (ANOVA) showed a significant effect of the different training schedules on studied parameters. The results revealed a different degree of platelet aggregation and a different initial velocity of platelet aggregation that changes during the different training schedules in horses that could represent a different protective endothelial mechanism. These findings could have an important role for a clearer knowledge of the physiological reference values of platelet aggregation and for a better interpretation of these variations during the training.

Iron profile in Thoroughbreds during a standard training program

OBJECTIVES

The aim of this study was to evaluate the modifications of some haematological parameters and iron profile during an 80-day training program and their relationship with athletic performance of performance horses.

METHODS

During the training period, 20 Thoroughbreds were subjected to a standardised exercise test, previously standardised for gallopers to evaluate athletic performance. The test was performed immediately before the beginning of the training program (T0) and after 30 days (T30), 60 days (T60) and 90 days (T90). For each horse, their velocities at blood lactate concentrations of 2 and 4 mmol/L (V2 and V4) and a heart rate of 200 beats/min (V200) were calculated to assess the effect of the training program on athletic performance. Blood samples were collected at 20-day intervals over a period of 80 days from the beginning of the training program.

RESULTS

One-way repeated measures analysis of variance (ANOVA) showed a statistically significant effect of days of training (time) on iron, ferritin, transferrin, total iron-binding capacity, transferrin saturation and unsaturated iron-binding capacity (P < 0.001 for all).

CONCLUSIONS

The results showed the influence of the intensity and duration of exercise on iron metabolism. These findings may be useful for evaluating the athletic status of horses during training and to assess the degree of training adaptability, providing an opportunity to modify the training schedule to achieve the desired performance.

Risonanza magnetica funzionale: Localizzazione dell'area motoria primaria in pazienti portatori di lesioni espansive cerebrali Risultati preliminari

La Risonanza Magnetica Funzionale (RMF) ha dimostrato di poter localizzare la sede di aree corticali funzionali in numerosi protocolli su volontari sani. La identificazione prechirurgica di aree corticali eloquenti è molto importante al fine della realizzazione di un intervento il meno lesivo possibile per la funzione. Il sowertimento più o meno grossolano della regione anatomica da parte di un processo espansivo rende spesso difficile la identificazione di determinati reperi anatomici.

Ci siamo proposti di studiare con RMF, su tomografo convenzionale, pazienti affetti da neoplasie intra ed extrassiali che interessavano il lobo frontale posteriore o quello parietale. Sono stati studiati quindici pazienti, tutti destrimani, di età compresa tra i 15 ed i 64 anni. Sono state ottenute mappe di attivazione, che hanno evidenziato aree di significativo aumento del segnale in regione parieto-frontale posteriore.

La morfologia delle aree di significativo aumento di segnale era il più delle volte di tipo serpiginoso. Quando l'effetto massa era netto, l'area attivata nell'emisfero patologico appariva dislocata rispetto a quella nell'emisfero controlaterale. Sino ad ora sono stati ripetuti gli esami di RMF dopo l'intervento chirurgico in tre pazienti che non presentavano deficit motori significativi all'arto superiore.

Neoplasms compressing or infiltrating cerebral cortex often alter the normal anatomy in such a way that the neurosurgeon can not easily localize and spare functional areas. Moreover, the results of mass effect on brain functional anatomy have not been extensively investigated in vivo yet.

Water temperature influences growth and gonad differentiation in European sea bass (Dicentrarchus labrax, L. 1758)

The effect of rearing temperature on gonad differentiation and growth was evaluated in sea bass (Dicentrarchus labrax). One control group (CG, n = 60) and two experimental groups (EG1, n = 30; EG2, n = 30) were selected. CG was reared at 15.0 °C during 10 days post-hatch (dph) and at 19.0 °C throughout the remaining larval and post-larval development. EG1 was exposed to 14.5 °C from 1 to 50 dph, followed by an increase to 20 °C until sampling (176 dph). EG2 was exposed to 14.5 °C from 1 to 37 dph, followed by an increase to 20 °C until sampling (226 dph); 30 fish from CG were randomly sampled at 176 dph (CG1, control for EG1) and 30 fish were sampled at 226 dph (CG2, control for EG2). Weight, total and fork length measurement, and gonad collection were performed. All biometric indices were higher in EG1 and EG2 than in CG1 and CG2, respectively. Histologic analysis reported 100% of undifferentiated gonads in CG1 and; EG1 reported 80% of undifferentiated gonads and 20% of gonads at early differentiation toward the male line. CG2 reported 34% of undifferentiated gonads, 10% of gonads at early differentiation toward the female line, 23% of gonads at early differentiation toward the male line, and 33% of gonads with intratesticular oocytes. EG2 reported 47% of gonads differentiated in testis, 33% gonads differentiated in ovary, and 20% of gonads with intratesticular oocytes. These results suggest that water temperature plays an important role in the process of gonad differentiation and growth of sea bass.

The peripartum period influenced the serum macromineral profile in mares

Abstract. Changes in metabolic requirements during pregnancy may produce nutritional imbalances predisposing mares to pathological conditions. Therefore, we aimed to examine changes in serum macrominerals during the peripartum period in mares. Fifteen pregnant mares (Group A) were monitored starting at the 263rd day of pregnancy until the 21st day after foaling. Seven non-pregnant and non-lactating mares were used as a control group (Group B). Group A was subjected to blood sampling within 24 ± 12 h after parturition (P) and then 7, 14 and 21 days after foaling (+1, +2, +3 weeks, respectively). Group B was subjected to regular sampling throughout the study to ensure that seasonal changes had no significant effect on studied parameters. Serum samples were analysed for serum electrolytes including sodium (Na+), potassium (K+), calcium (Ca+ + ), phosphorus (P+), chloride (Cl−) and magnesium (Mg+ + ). Two-way repeated measures of analysis of variance (ANOVA) was applied to evaluate significant effects of peripartum on electrolyte concentrations. Group A showed a decrease in Cl− concentrations (P = 0.011) after foaling and lower P+ concentrations (P = 0.015) compared to Group B throughout the study. The linear regression model showed an increase in Na+ concentrations (P = 0.002) and a gradual decrease in serum Ca+ +  (P = 0.001) during pregnancy. Because the most significant changes in serum electrolytes occurred within 2 weeks before and 2 weeks after foaling, monitoring serum electrolyte concentrations would indicate whether the mare needs further mineral supplementation at this stage. The significant changes in a mare's macromineral profile that we observed over the peripartum provide enhanced knowledge about mineral interrelations and their modifications during specific physiological conditions such as late pregnancy and early postpartum.

Metabolic profile of broodmares during late pregnancy and early post-partum

Pregnancy represents a specific physiological status characterized by continuous adjustments that affect maternal metabolism of all nutrients. In the last trimester of pregnancy, mare's nutrient requirements greatly increase and most pregnancy-associated diseases are likely to occur. Therefore, we aimed to assess the metabolic profile of broodmares focusing on the last 3 months of pregnancy and the early post-partum. Fifteen pregnant mares (Group A) were monitored from 263 ± 3 days of pregnancy until 21 days after foaling. Seven non-pregnant mares (Group B) were used as the control group. Blood samples were collected weekly by jugular venipuncture throughout the experimental period, and additional blood samples were collected within 24 ± 12 h of foaling. Obtained sera were analyzed for urea (Ur), creatinine (Cre), total protein (TP), total, direct and indirect bilirubin (tB, dB, iB), triglycerides (TG), total cholesterol (tChol) and β-hydroxybutyrate (BHB). During pregnancy, Ur (p = 0.015) and dB (p = 0.028) were higher in Group A than Group B. Serum Cre, tB, iB and TG (p < 0.001) decreased after foaling; furthermore, Group A exhibited lower tChol (p < 0.001) and higher BHB (p < 0.001) than Group B during the study. There were significant interactions of time × peripartum on Ur (p = 0.007), Cre (p < 0.001), tB (p = 0.018), TG (p < 0.001) and tChol (p < 0.001). These results can be used in the interpretation of biochemical studies in late gestation mares which develop systemic disease. The improved understanding of the metabolic profile during the peripartum might assist in monitoring the health status of the broodmares to promote foetal growth and well-being.

Hemostatic profile during late pregnancy and early postpartum period in mares

Hemostasis is a physiological process that prevents excessive blood loss and represents a protective mechanism at the time of delivery. Peripartum hemorrhage is a recurring hazardous condition to mare's health; therefore, we aimed to study mares' hemostatic profile to investigate whether physiological adjustments occur during late pregnancy and early postpartum. Fifteen pregnant mares have been monitored from the 34th week of pregnancy until the third week after foaling. Fifteen nonpregnant mares were used as control group. Jugular blood samples were analyzed for platelet count (Plt), prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen (Fb). Platelet count showed significant changes at foaling (P < 0.05) and a negative correlation (r = -0.968; P = 0.032) with postpartum. Prothrombin time changed (P < 0.05) showing a significant correlation (r = 0.675; P = 0.016) with late pregnancy. Fibrinogen concentrations changed throughout the experimental period (P < 0.0001). The linear regression model revealed a positive correlation (r = 0.9210; P < 0.0001) between Fb and late pregnancy and a negative correlation (r = -0.9583; P = 0.042) between Fb and early postpartum. The shortening in PT recorded in the imminence of parturition along with the increase in Plt and Fb at foaling might reflect a physiological hypercoagulable state that constrains excessive bleeding, enhancing mares' odds of surviving. Our research improves the knowledge about blood coagulation in periparturient mares providing specific information on routine coagulation tests that may support in monitoring mare's hemostatic profile during late pregnancy and early postpartum.

Changes in blood coagulation induced by exercise training in young athletic horses

Prothrombin Time (PT), Activated Partial Prothrombin Time (APTT), Fibrinogen concentration (Fbg) and Platelet number (Plt) were evaluated in 20 young athletic horses during a training program. A standardized exercise test (SET) was performed every month for three months. The V4 variations (the speed, in m/min, reached at the blood lactate concentration of 4 mmol/l) obtained for each test were calculated to assess the effect of training program on athletic performance. Blood samples were collected at 20-day intervals over a period of 80 days from the beginning of the training program. The V4 (P < 0.001), PT (P < 0.001), APTT (P < 0.01), Fbg (P < 0.01) and Plt (P < 0.001) varied throughout the training period showing that the modifications of clotting mechanism in response to training period may be considered as a normal physiological response of the hemostatic system to training exercise.

Cinnabarinic acid, an endogenous metabolite of the kynurenine pathway, activates type 4 metabotropic glutamate receptors

Cinnabarinic acid is an endogenous metabolite of the kynurenine pathway that meets the structural requirements to interact with glutamate receptors. We found that cinnabarinic acid acts as a partial agonist of type 4 metabotropic glutamate (mGlu4) receptors, with no activity at other mGlu receptor subtypes. We also tested the activity of cinnabarinic acid on native mGlu4 receptors by examining 1) the inhibition of cAMP formation in cultured cerebellar granule cells; 2) protection against excitotoxic neuronal death in mixed cultures of cortical cells; and 3) protection against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine toxicity in mice after local infusion into the external globus pallidus. In all these models, cinnabarinic acid behaved similarly to conventional mGlu4 receptor agonists, and, at least in cultured neurons, the action of low concentrations of cinnabarinic acid was largely attenuated by genetic deletion of mGlu4 receptors. However, high concentrations of cinnabarinic acid were still active in the absence of mGlu4 receptors, suggesting that the compound may have off-target effects. Mutagenesis and molecular modeling experiments showed that cinnabarinic acid acts as an orthosteric agonist interacting with residues of the glutamate binding pocket of mGlu4. Accordingly, cinnabarinic acid did not activate truncated mGlu4 receptors lacking the N-terminal Venus-flytrap domain, as opposed to the mGlu4 receptor enhancer, N-phenyl-7-(hydroxyimino)cyclopropa[b]chromen-1a-carboxamide (PHCCC). Finally, we could detect endogenous cinnabarinic acid in brain tissue and peripheral organs by high-performance liquid chromatography-tandem mass spectrometry analysis. Levels increased substantially during inflammation induced by lipopolysaccharide. We conclude that cinnabarinic acid is a novel endogenous orthosteric agonist of mGlu4 receptors endowed with neuroprotective activity.

Influence of transportation on serum concentrations of acute phase proteins in horse

The modifications of Haptoglobin (Hp), Serum Amyloid A (SAA), Fibrinogen (Fbg) and White Blood Cells (WBCs) were evaluated in 15 Saddle Italian horses. Ten horses were transported covering a distance of about 320 km within 4 h with an average speed of 80 km/h (experimental group) and five horses were not subject to transportation (control group). Blood was collected via jugular venipuncture before the transportation (T0), immediately after the transportation (T1), 12 (T12), 24 (T24) and 48 (T48)hours after the transportation in experimental group and at the same time point in control group. For each parameter statistical analysis of different groups and sampling time was performed using a two-way analysis of covariance, with the data before the transportation (T0) as the covariate, by the GLM procedure of SAS. For all parameters the interaction (Group × Time) was tested and it was resulted no significant. The application of statistical analysis showed significant differences between the control group and horses subjected to transportation (P<0.01), and the influence of sampling time (P<0.05) on Hp, SAA and WBCs. These modifications appeared to be innovative showing that equine Hp, generally considered as moderate acute phase protein, increases more rapidly than the SAA after transportation-induced stress.

Electrophoretic serum protein fraction profile during the different physiological phases in Comisana ewes

The aim of this study was to evaluate the influence of different physiological phases on serum total proteins and their fractions of ten Comisana ewes housed in Mediterranean area. From each animal, blood samples were collected at different physiological phases: late pregnancy, post-partum, early, mid-, end lactation and dry period. On all samples serum total proteins were determined by the biuret method, and albumin, α-globulins, β(1) -globulins, β(2) -globulins and γ-globulins concentrations were assessed using an automated system. One-way repeated measures analysis of variance was applied to determine the significant effect of different physiological phases on the parameters studied. During the late pregnancy and post-partum, total proteins, β1- and β2-globulins and γ-globulins showed the highest values. Starting from post-partum, α-globulins increased to reach their peaks in mid-lactation. Early lactation was characterized by low γ-globulins values. The increase in serum albumin concentration and the drop in some globulin fractions determined the significant increase in albumin/globulin ratio. The obtained results contributed to improve the knowledge on electrophoretic profile during the different physiological phases in ewes, confirming that pregnancy and lactation periods affect the protein metabolism. Particularly, serum protein fractions pattern could give information about dehydration, plasma volume expansion and hepatic function, which occur during the different physiological phases. Dynamics of the protein profile - from pregnancy to dry period - which are provided by our results, could be considered as guidelines for the management strategies to guarantee the nutritional needs of these animals during the different physiological phases and to avoid a decline of productive performance and consequently an economic loss.

Seasonal variations of the serum proteins in sheep and goats (Short Communication)

Abstract. The aim of this study was to assess the seasonal trend of the serum protein content of sheep and goats. The tested animals were six female goats (Maltese breed) and six female sheep (Valle del Belice breed). All animals were clinically healthy and not pregnant or lactating before or during the study. On blood samples, collected through an external jugular venipuncture every 30 days for 12 months, electrophoresis was performed using a semiautomated AGE system and then electrophoretic curves with the relative protein concentrations were analyzed. One way for repeated measure analysis of variance (ANOVA) was applied to determine the effect of time and by means of cosinor rythmometry, mesor (mean level), amplitude (half the range of oscillation) and acrophase (Φ, time of peak) were determined. The results showed a seasonal rhythm on Albumin and Alumin/Globulin ratio for sheep and goats, with different acrophases, winter for goats and spring for sheep. A seasonal rhythm was shown also in Alpha 2 globulins by sheep and in Beta globulins by goats. The difference in the acrophase can be attributed to a different production pattern of melatonin in goat, so the liver production of albumin is major during the winter that has a longer scotophase.

Training-induced modifications of circadian rhythmicity of peroxidative parameters in horses

The aim of this study was to evaluate the daily rhythms of peroxidative parameters in untrained and trained horses. Blood samples were collected every 4 h for a 48-h period for the determination of reactive oxygen metabolites test (d-ROMs), antioxidant barrier (Oxy-ads), thiol antioxidant barrier (SHp) and lipid peroxidation (LPO). Two-way anova showed a significant effect of time of day on all parameters studied, except on LPO. Higher values of Oxy-ads and SHp were observed in trained horses during both days of monitoring (p < 0.01). All studied parameters, except for LPO, showed robust daily rhythms. Their acrophases occurred during the day in untrained horses and in the evening in trained horses. Our results showed that training increases antioxidative capacity and demonstrated that the daily rhythms of antioxidative parameters can be modified by training.

Daily variations of serum lipids in Ovis aries under different lighting and feeding conditions

The aim of this study was to discriminate the impact of lighting and feeding conditions on the regulation of lipid metabolism in Ovis aries. Six clinically healthy female Comisana ewes, not pregnant and not lactating were kept under different environmental conditions: 12:12 light-dark (LD) cycle, constant darkness and fasting. Blood samples were collected at the end of each period of treatment every 4 h for a 24-h period. Blood concentration of triglycerides, total cholesterol and non-esterified fatty acid showed robust daily rhythmicity in ewes maintained under 12:12 LD cycle and fed ad libitum. Conversely, either constant darkness or fasting had a deep impact on all lipid parameters investigated. Our results suggest that lighting and feeding conditions have an impact on daily variations in lipid metabolism in ewes.

Levels of serum osteocalcin and some electrolytes in foal during the first six months of life (Brief Report)

Abstract. Bone is a dynamic tissue characterized by continuous bone formation and bone resorption. The transformation of the primordial part of the long bones (the cartilaginous matrix during the embryonal period) into the definitive bone (lamellar bone tissue) is completed after puberty. Osteocalcin, also called the vitamin k-dependent protein of bone and synthesized predominantly by osteoblasts and in lower way by odontoblasts, is incorporated into the extracellular matrix of bone (LEPAGE et al. 2001) and it may function as a useful indicator of the equine bone growth rate which decreases considerably with age. In particular, osteocalcin or bone Gla-protein is a small abundant non-collagenous calcium binding protein, indigenous to the organic matrix of bone dentin and possibly other mineralized tissue, which circulates in the blood (LEPAGE et al. 1991). It is accepted as a marker of osteoblast activity (RISTELI and RISTELI 1993) and plays a not yet defined role in the regulation of bone turnover (BOSKEY et al. 1998).

Modifications of some acute phase proteins and the white blood cell count in thoroughbreds during training

The concentrations of plasma fibrinogen and serum haptoglobin and the white blood cell count (WBC) were assessed in 17 thoroughbreds. All horses were trained for 80 days, six days a week, with one day of rest per week. Blood samples were collected from each animal by jugular venepuncture, at 06.00, every 20 days for a period of 80 days, and the fibrinogen and haptoglobin concentrations and WBC were determined. One-way repeated measures analysis of variance, followed by the Bonferroni test, was used to determine significant differences. Training was associated with a significant increase in the concentrations of plasma fibrinogen (P<0.01) and serum haptoglobin (P<0.0005), but had no significant effect on the WBC count.

Daily rhythms of serum and salivary parameters in goats

OBJECTIVE

Determine the daily rhythms of urea, bicarbonate, sodium, potassium, chloride, calcium, magnesium and inorganic phosphorus secretion in the serum and saliva of goats and whether there is a relationship between them.

DESIGN

Ten non-gravid, non-lactating does underwent a 30-day preconditioning period (natural 24-h photoperiod, environmental temperature 19-21 degrees C, relative humidity 40-50%, the same feeding regimen, offered as a single meal at 07:00 hours, and water ad libitum), following which saliva and blood samples were collected from each subject every 4 h for 2 days (starting at 08:00 hours) for measurement of urea and electrolytes.

RESULTS

Data analysis was conducted by one-way repeated measures analysis of variance (ANOVA) and by the single cosinor method. ANOVA showed a significant effect of time (0.001 < P < 0.01) on all the studied parameters in saliva and serum on both days. Cosinor analysis identified the periodic parameters and their acrophases (expressed in hours) during the 2 days of monitoring. Serum and salivary acrophases were all diurnal and were observed between 11:40 and 16:24 hours. No circadian rhythmicity was found for bicarbonate, magnesium or potassium in either saliva or serum.

CONCLUSION

There was a daily rhythm of secretion for the majority of the measured parameters, suggesting the potential role of saliva as an additional, reliable index for physiological, clinical, nutritional and chronophysiological studies.

Incidental detection by [11C]choline PET/CT of meningiomas in prostate cancer patients

AIM

Anti-androgenic hormonal therapy in prostate cancer patients with concomitant meningioma may result in tumor growth and development of neurological symptoms. Positron emission tomography/computed tomography (PET/CT) with [11C]choline is used for restaging prostate cancer patients with biochemical failure. In vitro and in vivo data support altered choline metabolism in meningiomas.

METHODS

During a retrospective study in prostate cancer patients with biochemical failure referred to our institution between November 2004 and January 2007, encephalic focal uptake of [11C]choline was incidentally noted in 4 patients, 2 of which had been taking luteinizing hormone-releasing hormone analogs.

RESULTS

Subsequent to the incidental finding, one patient underwent surgical removal of the meningioma; strict neuroradiological follow-up was planned for the 3 other patients.

CONCLUSION

We suggest that in prostate cancer patients candidate for anti-androgenic therapy the whole body [11C]choline PET/CT scan should include the whole skull to check for the possible presence of meningiomas. This could help to identify patients at risk for the development of neurological symptoms during anti-androgenic therapy and help the referring urologist in the clinical management of these patients.

Daily pattern of some fatty acids in the athletic horse

In the sport field, non-esterified fatty acids (NEFA) are important for the physical performance during the aerobic exercise of short intensity and long duration. In man, rat, goat and in the sedentary horse studies on the chronometabolism showed the presence of a circadian rhythm of the plasmatic concentration of NEFA while data for the athletic horse are lacking. To define a chronogram helpful for a specific planning and the differentiation of the training programmme in the athletic horse, the circadian pattern of some fatty acids (NEFA, palmitic, stearic, oleic, linoleic and linolenic acids) was studied in five Sella Italiana horses. These horses trained following a daily model of activity consisting of walk, trot, gallop and jump of obstacles of different heights. Blood samples were collected from the jugular vein every 4 h, starting at 08:00 hours, for 2 days to assess the concentrations of total NEFA (by spectrophotometry), palmitic, stearic, oleic, linoleic and linolenic acids (by gas chromatography). anova for repeated measures showed a statistical significant effect of the time of the day in NEFA, oleic and linolenic acids. The application of the periodic model showed the periodic pattern of NEFA, oleic, linoleic and linolenic acids. Acrophases were in the afternoon for all parameters. The results obtained showed a different trend of the circadian pattern of the studied parameters in the athletic horse than in the sedentary one because the physical activity and the post-prandial metabolism acted as zeitgebers.

Positron emission tomography/computed tomography introduction in the clinical management of patients with suspected recurrence of ovarian cancer: a cost-effectiveness analysis

Aim of this study was to evaluate the economic impact of the introduction of positron emission tomography/computed tomography (PET/CT) in the early detection of recurrent ovarian cancer through a cost-effectiveness analysis of different diagnostic strategies. Thirty-two consecutive patients with suspected ovarian cancer recurrence, studied by both contrast enhanced abdominal CT and PET/CT, were retrospectively included in the study. Three different diagnostic strategies were evaluated and compared: (1) CT only or baseline strategy; (2) PET/CT for negative CT or strategy A; (3) PET/CT for All or strategy B. For each one, expected costs, avoided surgery and incremental cost-effectiveness ratio (ICER) were calculated to identify the most cost-effective strategy. The number of positive patients increased from baseline strategy (20/32) to strategy A and B (30/32 and 29/32 respectively). Positron emission tomography/computed tomography reoriented physician choice in 31% and 62% of patients (strategies A and B respectively). Strategy A is dominated by strategy B, which is more expensive (2909 euro vs. 2958 euro), but also more effective (3 cases of surgery avoided) and presents an ICER of 226.77 euro per surgery avoided (range: 49.50-433.00 euro). Positron emission tomography/computed tomography introduction in this population is cost-effective and allowed to redirect the clinical management of patients towards more appropriate therapeutic choices.

Role of 18FDG-PET/CT in detecting relapse during follow-up of patients with Hodgkin's lymphoma

The role of 18FDG-PET/CT during follow-up of patients affected by Hodgkin's lymphoma (HL) in complete remission after treatment is not fully elucidated, since a wide use of 18F fluorodeoxyglucose positron emission tomography/computed tomography (18FDG-PET/CT) in this setting could be limited by a relative high rate of false-positive results. Herein, we summarize a retrospective analysis of 27 patients with Hodgkin's lymphoma in complete remission after the first-line (n = 20) or salvage (n = 7) therapy receiving serial 18FDG-PET/CT scans during follow-up. Out of 165 scans, 13 were suspected for relapse, which was confirmed in seven patients. All relapses were correctly identified by 18FDG-PET/CT positivity, with a 100% sensitivity; false-positive rate was 46% and negative predictive value was 100%. True-positive findings were mostly associated with multiple sites, subdiaphragmatic involvement, and/or previous sites of disease. According to our results, we conclude that performing routine PET/CT scan during follow-up of those patients who are at high risk of relapse would be advisable, although caution must be adopted when interpreting PET/CT results due to the relatively high rate of false-positive findings. If FDG abnormal uptake is present at multiple nodal sites, subdiaphragmatic lymph nodes, or previous sites of disease, histological verification of PET abnormal findings is warranted.

Supercalifragilisticexpialidocious: how the brain learns words never heard before

Vocabulary acquisition is such a major aspect of language learning in children, but also in adults when learning a foreign language, that a dedicated vocabulary learning device may exist within the language organ. To identify the relevant brain systems, we performed regional cerebral blood flow measurements in normal subjects while they were learning a list of neologisms or a list of word-nonword pairs. Structures implicated in phonological short-term memory (Broca's area, left temporo-parietal junction) were steadily activated during nonwords learning, while the left temporal lobe neocortical and paralimbic structures (parahippocampal region), associated with long-term memory, contributed to learning in a time-dependent manner, with maximal activation at the beginning of the process. The neural system specifically activated when learning new vocabulary was strongly lateralized to the left hemisphere. This evidence refines current models of memory function and supports theories which emphasise the importance of phonological competence in hemispheric dominance for language.

Serum homocysteine and oxidative stress evaluation during exercise in horse

The aim of the present work was to evaluate the influence of exercise on serum homocysteine and oxidative stress in Thoroughbreds during official races. For our study, ten Thoroughbred mares, 5 years old and clinically healthy, were used. The horses were trained to take part in an official 2100 meter race. Reactive oxygen species (dROMs), antioxidant barrier (Oxy-adsorbent), thiol antioxidant barrier (SHp) and homocysteine (sHcy) were investigated. Blood samples, collected from each horse at rest, immediately after the race, and 30 and 180 min after the end of the race, were collected by jugular venipuncture using vacutainer tubes with no additive for the assessment of dROMs, Oxy-adsorbent and SHp by means of a UV spectrophotometer, while serum total Hcy values were determined by high performance liquid chromatography with fluorimetric detection and isocratic elution. Statistical analysis, one way repeated measures analysis of variance (ANOVA), followed by Bonferroni's test, showed statistical differences (P<0.05 was considered statistically significant) for all parameters studied. Moreover, a coefficient of linear correlation (r) was computed for values of dROMs and sHcy for all sampling times but a significant linear regression (r = 0.94) was found only after the race. The variations of sHcy, dROMs, Oxy-adsorbent and SHp during the experimental period considered suggest the important role of oxidative status in the athletic horse. The systematic analysis of oxidative stress and its influence on homocysteine levels contribute to the clinical evaluation and assessment of the athletic performance of the horse.

Education and occupation as proxies for reserve in aMCI converters and AD: FDG-PET evidence

BACKGROUND

Previous reports have shown that higher education is associated with more severe brain pathology in patients with Alzheimer disease (AD), suggesting that these individuals have a functional reserve provided by education, which masks the clinical expression of a higher degree of neurodegeneration. It is unknown if a similar reserve mechanism exists in patients with amnestic mild cognitive impairment (aMCI). The aim of this study was to assess the impact of education and occupation on brain glucose metabolism (rCMRglc) measured with FDG-PET in aMCI and in a very large sample of subjects with probable AD (pAD).

METHODS

A total of 242 patients with pAD, 72 with aMCI, and 144 healthy controls participated in the study. At follow-up, 21 subjects with aMCI progressed to AD. A regression analysis was conducted (SPM2), with education and occupation as independent variables, and rCMRglc as dependent variable, adjusting for demographic data, global cognitive status, and neuropsychological scores.

RESULTS

The analysis showed a significant association between higher education/occupation and lower rCMRglc in posterior temporoparietal cortex and precuneus in pAD and aMCI converters, and no correlation in aMCI nonconverters and healthy controls. This means that, when submitted to FDG-PET for diagnostic evaluation, pAD and aMCI converters with higher education/occupation had, for comparable cognitive impairment, a more severe rCMRglc reduction than the ones with lower education/occupation.

CONCLUSIONS

This study suggests that education and occupation may be proxies for brain functional reserve, reducing the severity and delaying the clinical expression of Alzheimer disease (AD) pathology. The results in aMCI converters suggest that functional reserve is already at play in the predementia phase of AD.

Switch in the expression of mGlu1 and mGlu5 metabotropic glutamate receptors in the cerebellum of mice developing experimental autoimmune encephalomyelitis and in autoptic cerebellar samples from patients with multiple sclerosis

Recent evidence suggests that changes in the expression of membrane receptors/ion channels in cerebellar Purkinje cells contribute to the onset of cerebellar motor symptoms in patients with multiple sclerosis (MS). We examined the expression of group-I metabotropic glutamate receptors (mGlu1 and mGlu5 receptors) in the cerebellum of mice developing experimental autoimmune encephalomyelitis (EAE) and in autoptic cerebellar samples of MS patients. EAE was induced in mice by immunization with the 35-55 fragment of MOG (myelin oligodendrocyte glycoprotein). EAE mice showed a progressive loss of mGlu1a receptors in the cerebellum, associated with an increased expression of mGlu5 receptors. These changes were restricted to Purkinje cells and their dendritic arborization, as shown by immunohistochemistry. A reduced expression of mGlu1a receptors in cerebellar Purkinje cells was also found in 7 of 9 MS patients. In addition, a light/moderate to very strong mGlu5 receptor immunoreactivity was detected in Purkinje cells of 8 MS patients, but was always absent in non-MS control patients. In EAE mice, an acute treatment with the mGlu1 receptor enhancer, 9H-xanthene-9-carboxylic acid (4-trifluoromethyl-oxazol-2-yl)-amide (RO0711401), significantly improved motor coordination, whereas treatment with the mGlu5 receptor antagonists, 2-methyl-6-(phenylethynyl)-pyridine (MPEP) and 6-methyl-2-(phenylazo)-3-pyridinol (SIB-1757), had no effect. We conclude that mGlu1 receptor enhancers improve motor symptoms associated with EAE and might be helpful as symptomatic drugs in patients with MS.