Diagnostic value of whole body bone scan in horses

Scintigraphy is widely used in the assessment of musculoskeletal disorders and often it is considered as a screening tool in lame or poor performing horses. It is proved that nuclear scintigraphy is useful in highlighting the presence of lesions undetectable by clinical examination, in horses that do not respond to local analgesic blocks or with intermittent lameness[1]. Despite the usefulness of bone scan is proven, in a recent report, Quiney et al. observed that false-negative results predominate and may lead to missed diagnosis[2]. The aim of this study is to analyze the diagnostic usefulness of whole body bone scan in horses referred for lameness or poor performance. For this retrospective study, bone scans acquired at the Ospedale Veterinario Universitario di Lodi between July 2014 and February 2019 were reviewed. In the study have been included only horses that had a whole body bone scan. On the basis of the history, horses were classified as poor performing, for localized lameness or non-localized lameness. Scintigraphic findings were organized in five categories: definitive diagnosis, localization of the lameness, no findings related to the present clinical signs, findings of unlikely clinical significance and findings that need further investigations. A contingency table and a chi-squared test were used for the statistical analysis. One hundred and eighty horses underwent scintigraphy and 102 were included in the study; twenty-one horses were referred for lameness localized using diagnostic analgesia while in 44 horses the source of lameness was not identified. Thirty-seven horses had an history of poor performance. Statistical analysis highlighted that the only correlation between clinical history and scintigraphic findings was between horse referred for poor performance and findings of unlikely clinical significance (59,5% of horses with a poor performance diagnosis). A final diagnosis or localization of the source of pain were observed respectively in the 5.9% and in the 29.4% of horses. In 11 subjects (10.8%) were found increased radiopharmaceutical uptakes (IRU) of uncertain clinical significant that needed further investigations using analgesic blocks. In the 20% of cases, all referred for lameness, no findings related to the present clinical signs were found. In order to increase the capability of bone scintigraphy, it is mandatory to consider that the sensitivity and specificity are higher in specific regions[2] and the interpretation of the relevance of IRU must be based on detailed clinical examination. In conclusion, we confirm that whole body bone scintigraphy should not be considered a diagnostic screening especially in poor performing horses and that localization of lameness can improve the possibility of a positive result. [1] Dyson S.J. Musculoskeletal scintigraphy of the equine athlete. Semin Nucl Med, 44:4-14, 2014. [2] Quiney L., Ireland J., Dyson S.J. Evaluation of the diagnostic accuracy of skeletal scintigraphy in lame and poorly performing sports horses. Vet Radiol Ultrasound, 59:477-489, 2018

Impact of sand feed rate on the damage of railway wheel steels

The global railway industry plays a pivotal role in economic development, offering efficient transportation solutions. However, railways operating in desert environments face unique challenges due to windblown sand. This study investigates the influence of sand feed rates on wheel-rail wear in desert conditions. Experimental tests were conducted using a bidisc apparatus to simulate sand feed rates. Results indicate that low feed rates lead to spalling and pitting, while high rates increase abrasive and fatigue wear. A critical transition point at 0.4 g/min suggests sand-induced abrasion of wheel surfaces. Moreover, the research highlights the crucial role of sand feed rates not only in wear but also in surface roughness, further emphasizing the complex interplay between sand transport rates, adhesion, and wear mechanisms. These insights provide valuable guidance for mitigating wear-related challenges in desert railway operations and optimizing maintenance strategies

Can music be figurative? Exploring the possibility of crossmodal similarities between music and visual arts

According to both experimental research and common sense, classical music is a better fit for figurative art than jazz. We hypothesize that similar fits may reflect underlying crossmodal structural similarities between music and painting genres. We present two preliminary studies aimed at addressing our hypothesis. Experiment 1 tested the goodness of the fit between two music genres (classical and jazz) and two painting genres (figurative and abstract). Participants were presented with twenty sets of six paintings (three figurative, three abstract) viewed in combination with three sound conditions: 1) silence, 2) classical music, or 3) jazz. While figurative paintings scored higher aesthetic appreciation than abstract ones, a gender effect was also found: the aesthetic appreciation of paintings in male participants was modulated by music genre, whilst music genre did not affect the aesthetic appreciation in female participants. Our results support only in part the notion that classical music enhances the aesthetic appreciation of figurative art. Experiment 2 aimed at testing whether the conceptual categories ‘figurative’ and ‘abstract’ can be extended also to music. In session 1, participants were first asked to classify 30 paintings (10 abstract, 10 figurative, 10 ambiguous that could fit either category) as abstract or figurative and the to rate them for pleasantness; in session 2 participants were asked to classify 40 excerpts of music (20 classical, 20 jazz) as abstract or figurative and to rate them for pleasantness. Paintings which were clearly abstract or figurative were all classified accordingly, while the majority of ambiguous paintings were classified as abstract. Results also show a gender effect for painting’s pleasantness: female participants rated higher ambiguous and abstract paintings. More interestingly, results show an effect of music genre on classification, showing that it is possible to classify music as figurative or abstract, thus supporting the hypothesis of cross-modal similarities between the two sensory-different artistic expressions

Genotoxicity of DrinkingWater Disinfectants in Plant Bioassays

The genotoxicity of two widely used drinking water disinfectants, sodium hypochlorite (NaClO) and chlorine dioxide (ClO2), and a new disinfectant, peracetic acid (PAA, CH3-CO-COOH), was evaluated in three short-term plant tests: (1) induction of anaphase chromosome aberrations in the root cells of Allium cepa, (2) micronucleus induction in the root cells of Vicia faba, and (3) micronucleus induction in Tradescantia pollen cells. The study was carried out in the laboratory by directly exposing the plants to several concentrations of the disinfectants in redistilled water at unadjusted (acid) and adjusted (neutral) pHs. Both 0.1 and 0.2 mg/l NaClO induced chromosome aberrations in the Allium cepa test at acid pH, but concentrations up to 0.5 mg/l of all the disinfectants were negative at neutral pH. Concentrations ranging from 0.1 to 0.5 mg/l NaClO, ClO2, and PAA induced micronuclei in Vicia faba at acid pH, while 1–2 mg/l NaClO and ClO2 and 0.5–2 mg/l PAA gave positive responses at neutral pH. Most of concentrations of ClO2 produced positive responses in the Tradescantia micronucleus test. In general, the highest levels of genotoxicity were observed under acid conditions; at acid pH, significant effects were induced by low concentrations of ClO2 and PAA. Since the test concentrations of disinfectants are typical of those encountered in the biocidal treatment of tap water and similar concentrations are consumed daily by a large number of people, the genotoxicity of these compounds may constitute a significant public health concern

Brain imaging in rabbits : preliminary results of CBF variation by different anaestethic drugs

In the last decades the animal model has been usually considered as a research tool, especially for functional studies and brain imaging. Although general anesthesia and sedation are fundamental requirements to perform nuclear imaging in veterinary patients, very few studies have been published on the effect of anesthesia itself, on brain perfusion. Brain SPECT in humans is widely applied to assess brain perfusion mainly in awake patients. The aim of the study was to evaluate general brain perfusion in rabbits through a non-invasive nuclear medicine technique, before and after the administration of different anesthetic protocols commonly used for veterinary patients. Ten male New Zeland White rabbits of 6 months of age were enrolled in the prospective study. Before SPECT examinations, the rabbits underwent CT studies of the skull in order to exclude any gross malformations or lesions and to acquire images for CT/SPECT fusion. 99mTc-HMPAO brain SPECT scans were acquired with a single head gamma camera: circular orbit, continuos rotation 10 seconds/step and 120 steps. During the first session 99mTc-HMPAO was IV injected in two groups of five awake rabbits, with a randomized selection. The first one was subsequently anesthetized with propofol and the other with dexmedetomidine. The same procedure was repeated three weeks later when the injection of the radiopharmaceutical was performed after the induction of general anaesthesia. The brain perfusion uptake index (BPUi%) was calculated as the percentage ratio between total counts in the brain and injected activity. Rabbits anesthetized with propofol showed exactly the same tracer distribution in both injection condition: awake or asleep. The radiopharmaceutical was concentrated in the brain but a generalized distribution was observed also in the facial muscles. On the contrary when dexmedetomidine was used, rabbits anesthetized after the 99mTc-HMPAO injection showed a distribution similar to propofol group, while when the radiotracer was injected after the anesthetic drug, a generalized reduction of the uptake was observed especially in extra-encephalic tissues. The average BPUi% values were about 1.6% for all rabbits anesthetized with propofol and for rabbits injected with 99mTc-HMPAO before dexmedetomidine administration. Animals injected with 99mTc- HMPAO after dexmedetomidine administration showed a lower value of BPUi% equal to about 1.25 %. Although the major limitation of our study is the small number of subjects analyzed, our results showed that when propofol is used as anesthetic drug, any difference in brain perfusion occurred if the radiotracer was injected prior or before anesthesia. On the contrary the vasocostriction of dexmedetomidine is responsible of a mild reduction of the IRU in the brain and a good inhibition of tracer uptake in other tissues. These preliminary data suggest that the use of propofol in uncooperative patients, that need sedation before brain perfusion studies, could not influence the CBF. On the other hand the results of the CBF in rabbits medicated with dexmedetomidine before tracer injection, suggest a possible neuronal protective proprieties of this drug

Teg® and rotem® traces: Clinical applications of viscoelastic coagulation monitoring in neonatal intensive care unit

The concentration of the majority of hemostatic proteins differs considerably in early life, especially in neonates compared to adulthood. Knowledge of the concept of developmental hemostasis is an essential prerequisite for the proper interpretation of conventional coagulation tests (CCT) and is critical to ensure the optimal diagnosis and treatment of hemorrhagic and thrombotic diseases in neonatal age. Viscoelastic tests (VETs) provide a point-of-care, real-time, global, and dynamic assessment of the mechanical properties of the coagulation system with the examination of both cellular and plasma protein contributions to the initiation, formation, and lysis of clots. In this work, we provide a narrative review of the basic principles of VETs and summarize current evidence regarding the two most studied point-of-care VETs, thromboelastography (TEG®) and rotational thromboelastometry (ROTEM®), in the field of neonatal care. A literature analysis shows that viscoelastic hemostatic monitoring appears to be a useful additive technique to CCT, allowing targeted therapy to be delivered quickly. These tools may allow researchers to determine the neonatal coagulation profile and detect neonatal patients at risk for postoperative bleeding, coagulation abnormalities in neonatal sepsis, and other bleeding events in a timely manner, guiding transfusion therapies using the goal-oriented transfusion algorithm. However, diagnosis and treatment algorithms incorporating VETs for neonatal patients in a variety of clinical situations should be developed and applied to improve clinical outcomes. Further studies should be performed to make routinary diagnostic and therapeutic application possible for the neonatal population

Magic angle nella RM a bassa intensità di campo: è solo un errore di posizionamento?

Scopo del lavoro. Nell\u2019interpretazione delle immagini di Risonanza Magnetica (RM) deve essere tenuto in considerazione che la posizione delle strutture tenodesmiche rispetto al campo magnetico pu\uf2 provocare un aumento di segnale delle stesse, mimando una lesione1,2,3,4,5,6. Tale artefatto viene definito \u201cMagic Angle\u201d ed \ue8 gi\ue0 stato descritto in letteratura a carico dei leg. collaterali (CL) del- l\u2019articolazione interfalangea distale (DIPJ)2,3,5,6 del tendine flessore profondo del dito (DDFT)1,4,5 e dei legamenti sesamoidei obliqui (OSL)3. Tale artefatto pu\uf2 presentarsi utilizzando sia sistemi RM ad alto che basso campo quando le strutture anatomiche prima elencate si posizionano a circa 54\ub0 rispetto al campo magnetico (CM). In nessuno studio per\uf2 vengono descritte le alterazioni di se- gnale riconducibili a Magic Angle a carico degli OSL utilizzando posizionamenti che mimino di- fetti conformazionali dell\u2019estremit\ue0 distale del cavallo (Toe-in/Toe-out). Lo scopo del presente stu- dio \ue8 quello di verificare la presenza di Magic Angle a carico degli OSL nel cavallo, utilizzando un tomografo a basso campo con CM verticale e posizionando l\u2019arto in modo tale da simulare difetti conformazionali. Gli autori si propongono inoltre di verificare quali sequenze, tra quelle comune- mente inserite in un protocollo standard, siano le pi\uf9 sensibili a tale artefatto. Materiali e metodi. Sono stati sottoposti ad esame RM utilizzando un tomografo a basso campo n=3 arti isolati sinistri di soggetti sottoposti ad eutanasia per ragioni non correlate allo studio. Ogni arto \ue8 stato posizionato mantenendo l\u2019asse sagittale perpendicolare al CM, mimando il posiziona- mento \u201cin-vivo\u201d con il soggetto in decubito laterale sinistro. Per ogni arto sono state eseguite scan- sioni RM lungo il piano trasversale, utilizzando un protocollo standard previsto per esami clinici in cavalli affetti da zoppia che comprendeva sequenze pesate in T1, T2, Proton Density (PD) e se- quenze ad inversione con soppressione del segnale lipidico (STIR). Per verificare l\u2019assenza di le- sioni a carico degli OSL sono state acquisite le scansioni mantenendo l\u2019arto in posizione neutra (0\ub0). Successivamente, ogni arto \ue8 stato ruotato lungo l\u2019asse sagittale di 4\ub0, 8\ub0, 12\ub0 e 16\ub0, sia in senso orario che antiorario e per ciascun grado di rotazione il protocollo RM \ue8 stato ripetuto. L\u2019intensit\ue0 di segnale a carico degli OSL \ue8 stata misurata in ogni sequenza e per ogni posiziona- mento impiegando un software dedicato. Ogni misurazione \ue8 stata ripetuta tre volte ed \ue8 stata poi calcolata la media. Il test t di sudent \ue8 stato quindi utilizzato per valutare la significativit\ue0 dell\u2019in- cremento di segnale rispetto alla media. La significativit\ue0 \ue8 stata ritenuta positiva con a=0,05. Risultati. Il segnale a carico OSL laterale e mediale con l\u2019arto in posizione neutra era pressoch\ue9 so- vrapponibile. \uc8 stato invece osservato come all\u2019aumentare del grado di rotazione si verificasse un aumento dell\u2019intensit\ue0 di segnale a carico dell\u2019uno o dell\u2019altro legamento. Infatti, ruotando l\u2019arto in senso orario (+4\ub0, +8\ub0, +12\ub0, +16\ub0) \ue8 stato osservato un incremento lineare di segnale dell\u2019OSL me- diale, posto verso l\u2019alto. Viceversa, ruotando l\u2019arto in senso antiorario, l\u2019aumento d\u2019intensit\ue0 del se- gnale si \ue8 verificato a carico dell\u2019OSL laterale, posto verso il basso. Nonostante l\u2019incremento linea- re di segnale e la corrispondenza tra localizzazione dell\u2019iperintensit\ue0 e direzione della rotazione, una significativit\ue0 statistica \ue8 stata osservata solo con rotazioni di 16\ub0 e -16\ub0. Conclusioni. Nel presente studio \ue8 stato osservato come, in tutte le sequenze, ad un incremento del grado di rotazione corrispondesse un aumento del segnale legamentoso riconducibile a Magic An- gle. \uc8 stata inoltre riscontrata una stretta relazione tra localizzazione dell\u2019iperintensit\ue0 e direzione della rotazione. Gli scarsi valori di significativit\ue0 statistica possono essere ricondotti alla ridotta nu- merosit\ue0 del campione ma soprattutto agli elevati valori di deviazione standard dovuti alla presen- za di segnale disomogeneo caratteristico degli OSL. Sebbene in letteratura sia stato descritto che l\u2019aumento del Tempo di Eco (TE) possa ridurre, fino ad annullare, la presenza del Magic Angle6, nel presente studio, utilizzando le sequenze normal- mente impiegate in esami RM di tipo clinico, tale evenienza non \ue8 stata osservata. Un corretto posizionamento dell\u2019arto all\u2019interno del CM \ue8 indispensabile per ovviare alla compar- sa del Magic Angle. Tuttavia, in presenza di rotazioni del piede secondo il piano soleare identifica- bili come Toe in/Toe out, \ue8 opportuno prestare molta attenzione all\u2019aumento di segnale osservabile a carico degli OSL al fine di non commettere errori nella diagnosi ed interpretare la presenza di un artefatto come una desmopatia. Per questa ragione, in accordo con altri autori3, si consiglia di con- siderare come segno di patologia legamentosa non solo l\u2019iperintensit\ue0 di segnale ma anche varia- zioni nelle dimensioni e nella forma e l\u2019eventuale presenza di entesiofiti