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1.
Proc Biol Sci ; 290(2008): 20231029, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37817600

RESUMEN

Variation in formant frequencies has been shown to affect social interactions and sexual competition in a range of avian species. Yet, the anatomical bases of this variation are poorly understood. Here, we investigated the morphological correlates of formants production in the vocal apparatus of African penguins. We modelled the geometry of the supra-syringeal vocal tract of 20 specimens to generate a population of virtual vocal tracts with varying dimensions. We then estimated the acoustic response of these virtual vocal tracts and extracted the centre frequency of the first four predicted formants. We demonstrate that: (i) variation in length and cross-sectional area of vocal tracts strongly affects the formant pattern, (ii) the tracheal region determines most of this variation, and (iii) the skeletal size of penguins does not correlate with the trachea length and consequently has relatively little effect on formants. We conclude that in African penguins, while the variation in vocal tract geometry generates variation in resonant frequencies supporting the discrimination of conspecifics, such variation does not provide information on the emitter's body size. Overall, our findings advance our understanding of the role of formant frequencies in bird vocal communication.


Asunto(s)
Spheniscidae , Animales , Spheniscidae/fisiología , Vocalización Animal/fisiología , Tamaño Corporal , Acústica , Comunicación
2.
Animals (Basel) ; 12(6)2022 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35327134

RESUMEN

A catastrophic fracture of the radial carpal bone experienced by a racehorse during a Palio race was analyzed. Computational modelling of the carpal joint at the point of failure informed by live data was generated using a multibody code for dynamics simulation. The circuit design in a turn, the speed of the animal and the surface characteristics were considered in the model. A macroscopic examination of the cartilage, micro-CT and histology were performed on the radio-carpal joint of the limb that sustained the fracture. The model predicted the points of contact forces generated at the level of the radio-carpal joint where the fracture occurred. Articular surfaces of the distal radius, together with the proximal articular surface of small carpal bones, exhibited diffuse wear lines, erosions of the articular cartilage and subchondral bone exposure. Even though the data in this study originated from a single fracture and further work will be required to validate this approach, this study highlights the potential correlation between elevated impact forces generated at the level of contact surfaces of the carpal joint during a turn and cartilage breakdown in the absence of pre-existing pathology. Computer modelling resulted in a useful tool to inversely calculate internal forces generated during specific conditions that cannot be reproduced in-vivo because of ethical concerns.

3.
Vet Sci ; 8(8)2021 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-34437469

RESUMEN

Intravenous iodinated contrast (IVIC) medium is routinely administered to dogs. Scattered information exists regarding the serum biochemical or urinary profiles associated with the administration of IVIC in dogs. The aim of the study was to describe, compare, and discuss from the perspective of previous studies the alterations in serum biochemical and urinary parameters before (T0) and within one week (T1) of the IVIC administration during routine computed tomography (CT) scan evaluation of 22 dogs. Mature dogs presenting for CT scan evaluation for preoperative oncology staging/surgical planning were included. T1 evaluation was performed within one week of IVIC administration. Statistically significant differences in serum total protein, albumin, chloride, calcium, and phosphorus concentrations, urine protein to creatinine ratio, and urine specific gravity were found between T1 and T0. At T1, the serum creatinine concentration was within reference ranges in all dogs but one. An increase in the urine protein to creatinine ratio was observed in four samples, one of which was non-proteinuric at T0. Changes in biochemistry and urine parameters between T0 and T1 were not considered clinically significant.

4.
Animals (Basel) ; 11(5)2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-34064742

RESUMEN

Dogs with benign intra-pelvic rectal or vaginal masses show symptoms indicating compression on the adjacent organs. Clinical signs usually develop late when the lesion is large enough to interfere functionally. The dogs were referred for severe fecal and/or urinary tenesmus. The data collected included signalment, clinical signs, results of physical examination, pre-surgical diagnostic tests, surgical technique used, surgical complications and histological findings. Digital rectal and vaginal examination allowed the detection of a mass occupying space in the pelvic cavity in all patients. Abdominal ultrasonography and/or total body computed tomography (CT) were used to better characterize the lesion and to exclude a metastatic spread of the tumor in case of malignancy. A dorsal approach to the rectum, a dorsal episiotomy, a midline celiotomy, and a combined perineal and abdominal approach were performed to remove the mass. No postoperative complications were observed. Benign and well-differentiated malignant mesenchymal neoplasms were histologically diagnosed. As a consequence of the chronic urethral compression caused by the mass, urinary incontinence and/or urinary retention were observed for a few postoperative days. Fecal tenesmus resolved in all cases in the immediate postoperative period. The dogs' quality of life quickly improved after surgery, especially considering the serious and life-threatening pre-surgical clinical conditions. Both the recovery time after surgery and overall survival were also evaluated.

5.
Vet Comp Oncol ; 19(4): 651-660, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33751759

RESUMEN

Canine oral malignant melanoma is locally invasive and highly metastatic. At present, the best option for local control is en bloc excision followed by radiation if excision margins are incomplete. Adjuvantly, the role of chemotherapy is dubious while immunotherapy appears encouraging. This retrospective study evaluated 155 dogs with oral malignant melanomas (24 stage I, 54 stage II, 66 stage III and 11 stage IV) managed in a single institution. The aim was to evaluate the differences in median survival time (MST) and disease-free interval (DFI) between dogs which, at presentation, were treated surgically with a curative intent (group 1) vs those marginally excised only (group 2). MST in group 1 was longer than in group 2 (594 vs 458 days), but no significant difference was found (P = .57); a statistical difference was, however, found for DFI (232 vs 183 days, P = .008). In the subpopulation of vaccinated dogs, the impact of adjuvant anti-CSPG4 DNA electrovaccination was then evaluated (curative intent, group 3, vs marginal, group 4); a significant difference for both MST (1333 vs 470 days, respectively, P = .03) and DFI (324 vs 184 days, respectively, P = .008) was found. Progressive disease was significantly more common in dogs undergoing marginal excision than curative intent excision for both the overall population (P = .03) and the vaccinated dogs (P = .02). This study pointed out that, after staging, wide excision together with adjuvant immunotherapy was an effective approach for canine oral malignant melanoma.


Asunto(s)
Vacunas contra el Cáncer/uso terapéutico , Enfermedades de los Perros , Melanoma , Neoplasias de la Boca , Adyuvantes Inmunológicos/uso terapéutico , Animales , ADN , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/cirugía , Perros , Márgenes de Escisión , Melanoma/tratamiento farmacológico , Melanoma/cirugía , Melanoma/veterinaria , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/cirugía , Neoplasias de la Boca/veterinaria , Estudios Retrospectivos , Neoplasias Cutáneas , Resultado del Tratamiento , Vacunas de ADN/uso terapéutico , Melanoma Cutáneo Maligno
6.
Comp Med ; 67(2): 147-156, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28381315

RESUMEN

Research in neurooncology traditionally requires appropriate in vivo animal models, on which therapeutic strategies are tested before human trials are designed and proceed. Several reproducible animal experimental models, in which human physiologic conditions can be mimicked, are available for studying glioblastoma multiforme. In an ideal rat model, the tumor is of glial origin, grows in predictable and reproducible patterns, closely resembles human gliomas histopathologically, and is weakly or nonimmunogenic. In the current study, we used MRI and histopathologic evaluation to compare the most widely used allogeneic rat glioma model, C6-Wistar, with the F98-Fischer syngeneic rat glioma model in terms of percentage tumor growth or regression and growth rate. In vivo MRI demonstrated considerable variation in tumor volume and frequency between the 2 rat models despite the same stereotactic implantation technique. Faster and more reproducible glioma growth occurred in the immunoresponsive environment of the F98-Fischer model, because the immune response is minimized toward syngeneic cells. The marked inability of the C6-Wistar allogeneic system to generate a reproducible model and the episodes of spontaneous tumor regression with this system may have been due to the increased humoral and cellular immune responses after tumor implantation.


Asunto(s)
Modelos Animales de Enfermedad , Glioma/patología , Ratas/inmunología , Aloinjertos/inmunología , Aloinjertos/patología , Animales , Glioma/inmunología , Isoinjertos/inmunología , Isoinjertos/patología , Imagen por Resonancia Magnética/veterinaria , Ratas/genética , Ratas Endogámicas F344/genética , Ratas Endogámicas F344/inmunología , Ratas Wistar/genética , Ratas Wistar/inmunología , Reproducibilidad de los Resultados
7.
Nanomedicine (Lond) ; 12(6): 639-656, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28186465

RESUMEN

AIM: Methotrexate-loaded biocompatible nanoparticles were tested for preliminary efficacy in glioma treatment. MATERIALS & METHODS: Behenic acid nanoparticles, prepared by the coacervation method, were loaded with the ester prodrug didodecylmethotrexate, which was previously tested in vitro against glioblastoma human primary cultures. Nanoparticle conjugation with an ApoE mimicking chimera peptide was performed to obtain active targeting to the brain. RESULTS & CONCLUSION: Biodistribution studies in healthy rats assessed the superiority of ApoE-conjugated formulation, which was tested on an F98/Fischer glioma model. Differences were observed in tumor growth rate (measured by MRI) between control and treated rats. In vitro tests on F98 cultured cells assessed their susceptibility to treatment, with consequent apoptosis, and allowed us to explain the apoptosis observed in glioma models.


Asunto(s)
Glioma/tratamiento farmacológico , Metotrexato/administración & dosificación , Nanopartículas/administración & dosificación , Profármacos/administración & dosificación , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Humanos , Lípidos/administración & dosificación , Lípidos/química , Metotrexato/química , Nanopartículas/química , Profármacos/química , Ratas , Distribución Tisular
8.
Eur J Pharm Biopharm ; 88(3): 746-58, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25445304

RESUMEN

Paclitaxel loaded solid lipid nanoparticles (SLN) of behenic acid were prepared with the coacervation technique. Generally, spherical shaped SLN with mean diameters in the range 300­600 nm were obtained. The introduction of charged molecules, such as stearylamine and glycol chitosan into the formulation allowed to obtain positive SLN with Zeta potential in the 8-20 mV range and encapsulation efficiency in the 25­90% range.Blood­brain barrier (BBB) permeability, tested in vitro through hCMEC/D3 cells monolayer, showed a significantly increase in the permeation of Coumarin-6, used as model drug, when vehicled in SLN. Positive-charged SLN do not seem to enhance permeation although stearylamine-positive SLN resulted the best permeable formulation after 24 h.Cytotoxicity studies on NO3 glioblastoma cell line demonstrated the maintenance of cytotoxic activity of all paclitaxel-loaded SLN that was always unmodified or greater compared with free drug. No difference in cytotoxicity was noted between neutral and charged SLN.Co-culture experiments with hCMEC/D3 and different glioblastoma cells evidenced that, when delivered in SLN, paclitaxel increased its cytotoxicity towards glioblastoma cells.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Barrera Hematoencefálica/metabolismo , Neoplasias Encefálicas/patología , Sistemas de Liberación de Medicamentos , Glioblastoma/patología , Paclitaxel/administración & dosificación , Antineoplásicos Fitogénicos/farmacocinética , Antineoplásicos Fitogénicos/uso terapéutico , Barrera Hematoencefálica/citología , Barrera Hematoencefálica/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Línea Celular Tumoral , Permeabilidad de la Membrana Celular , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Portadores de Fármacos/química , Liberación de Fármacos , Estabilidad de Medicamentos , Glioblastoma/tratamiento farmacológico , Humanos , Lípidos/química , Nanopartículas/química , Paclitaxel/farmacocinética , Paclitaxel/uso terapéutico , Tamaño de la Partícula , Propiedades de Superficie
9.
BMC Vet Res ; 10 Suppl 1: S9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25238113

RESUMEN

BACKGROUND: Stapled jejunocecal anastomoses are commonly performed in equine abdominal surgery. They carry higher complication rates compared to handsewn techniques. In human surgery various causes likely to lead to failure of stapled techniques have been evaluated, including staple line failure. Recently Freeman proposed a technique to perform a stapled jejunocecal anastomosis in horses while avoiding blind pouch formation. The aim of this study is to describe a method for stapled side-to-side jejunocecal anastomosis in horses and to compare it with other techniques with computed tomography to assess stomal area, shape and blind pouch size. METHODS: Intestinal specimens comprising the cecum, ileum and jejunum from 18 horses were collected and were divided into three groups. In Group S a standard stapled side-to-side jejunocecal anastomosis was performed. In Group F the anastomosis was performed using a modified technique proposed by Freeman. In Group G the anastomosis was performed with a modified technique proposed by the authors. Inflated bowel segments were CT scanned to obtain a MultiPlanar Reconstruction of the stoma and afferent small intestine before calculating the cross-sectional area of each of these regions. The ratio of the measured areas was compared between the three techniques. The volume of the blind-end pouch was measured and its ratio with the intestinal area compared between techniques. The cecum was opened and the length of the stoma measured with a caliper and compared to the intended initial length. RESULTS: The stomal/intestinal area ratio was not significantly different between techniques. CONCLUSIONS: Both the Freeman and the new (G) technique were comparable to the standard technique in terms of stomal area, stomal shape and difference in stomal elongation. They consistently produced a smaller blind pouch and allowed easier placement of the staplers.


Asunto(s)
Anastomosis Quirúrgica/veterinaria , Ciego/cirugía , Caballos/cirugía , Yeyuno/cirugía , Grapado Quirúrgico/veterinaria , Anastomosis Quirúrgica/métodos , Animales
10.
J Pharm Sci ; 103(7): 2157-2165, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24824141

RESUMEN

The major obstacle to glioblastoma pharmacological therapy is the overcoming of the blood-brain barrier (BBB). In literature, several strategies have been proposed to overcome the BBB: in this experimental work, solid lipid nanoparticles (SLN), prepared according to fatty acid coacervation technique, are proposed as the vehicle for doxorubicin (Dox), to enhance its permeation through an artificial model of BBB. The in vitro cytotoxicity of Dox-loaded SLN has been measured on three different commercial and patient-derived glioma cell lines. Dox was entrapped within SLN thanks to hydrophobic ion pairing with negatively charged surfactants, used as counterions. Results indicate that Dox entrapped in SLN maintains its cytotoxic activity toward glioma cell lines; moreover, its permeation through hCMEC/D3 cell monolayer, assumed as a model of the BBB, was increased when the drug was entrapped in SLN. In conclusion, SLN proved to be a promising vehicle for the delivery of Dox to the brain in glioblastoma treatment.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Neoplasias Encefálicas/patología , Doxorrubicina/administración & dosificación , Portadores de Fármacos/química , Ácidos Grasos/química , Glioblastoma/patología , Nanopartículas/química , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacología , Antibióticos Antineoplásicos/uso terapéutico , Barrera Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamiento farmacológico , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Liberación de Fármacos , Glioblastoma/tratamiento farmacológico , Humanos , Tamaño de la Partícula , Permeabilidad , Cultivo Primario de Células , Solubilidad , Células Tumorales Cultivadas
11.
J Digit Imaging ; 27(5): 563-70, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24793019

RESUMEN

Picture Archiving and Communications Systems (PACS) are the most needed system in a modern hospital. As an integral part of the Digital Imaging and Communications in Medicine (DICOM) standard, they are charged with the responsibility for secure storage and accessibility of the diagnostic imaging data. These machines need to offer high performance, stability, and security while proving reliable and ergonomic in the day-to-day and long-term storage and retrieval of the data they safeguard. This paper reports the experience of the authors in developing and installing a compact and low-cost solution based on open-source technologies in the Veterinary Teaching Hospital for the University of Torino, Italy, during the course of the summer of 2012. The PACS server was built on low-cost x86-based hardware and uses an open source operating system derived from Oracle OpenSolaris (Oracle Corporation, Redwood City, CA, USA) to host the DCM4CHEE PACS DICOM server (DCM4CHEE, http://www.dcm4che.org ). This solution features very high data security and an ergonomic interface to provide easy access to a large amount of imaging data. The system has been in active use for almost 2 years now and has proven to be a scalable, cost-effective solution for practices ranging from small to very large, where the use of different hardware combinations allows scaling to the different deployments, while the use of paravirtualization allows increased security and easy migrations and upgrades.


Asunto(s)
Almacenamiento y Recuperación de la Información/economía , Almacenamiento y Recuperación de la Información/métodos , Administración de la Práctica Veterinaria/economía , Administración de la Práctica Veterinaria/organización & administración , Sistemas de Información Radiológica/economía , Sistemas de Información Radiológica/organización & administración , Seguridad Computacional , Programas Informáticos , Medicina Veterinaria
12.
J Vet Med ; 2014: 234738, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-26464922

RESUMEN

The aim of this study is to compare handsewn and stapled jejunocecal anastomosis with different stomal lengths in terms of anatomical differences. Group 1 underwent a two-layer handsewn jejunocecal side-to-side anastomosis (HS); Group 2 received a stapled jejunocecal side-to-side anastomosis (GIA). Each group was divided into two subgroups (HS80 and HS100, GIA80 and GIA100). Specimens were inflated and CT scanned. The stomal/jejunal area ratio and blind end pouch volume/area were measured and compared. Effective length of the stoma was measured and compared with the initial length. Stomal/jejunal area ratio was 1.1 for both 80 techniques, 1.6 for the GIA100, and 1.9 for the HS100 technique. Both HS and GIA techniques produced a blind end pouch and exhibited a mean increase of the final stomal length ranging from 6 to 11% greater than the original stomal length. All techniques will exhibit a length increase of the final stomal length compared to the intended stomal length, with a consequent increase in stomal area. Stapled techniques consistently produced a large distal blind end pouch. Length of a jejunocecal anastomosis should be selected in accordance with the diameter of afferent jejunum, and the 80 mm stomal length could be deemed sufficient in horses.

13.
J Feline Med Surg ; 11(10): 869-72, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19464217

RESUMEN

A 12-year-old male cat was referred for progressive limb weakness lasting 2 weeks. Physical examination detected muscle atrophy and bilateral renomegaly with distortion of the renal contours. The cat was ambulatory but tetraparetic. It showed a peculiar posture on forelimbs with bilateral flexion of the carpi and extrarotation of forearms. The cat was unable to go upstairs or jump. Neurological examination showed findings compatible with peripheral nervous system involvement. Histopathological findings revealed a high grade non-B, non-T cell renal lymphoma and peripheral neuropathy characterised by demyelination, axonal degeneration and muscle denervation. In the absence of congenital, metabolic and infectious diseases or exposure to toxins, a paraneoplastic peripheral neuropathy was hypothesised. In humans and dogs, paraneoplastic peripheral neuropathies have been documented with different neoplastic processes including lymphoproliferative disorders. To the authors' knowledge, this is the first report of suspected paraneoplastic polyneuropathy in a cat with malignant tumour.


Asunto(s)
Enfermedades de los Gatos/etiología , Linfoma no Hodgkin/veterinaria , Polineuropatía Paraneoplásica/veterinaria , Enfermedades del Sistema Nervioso Periférico/veterinaria , Animales , Antineoplásicos Hormonales/administración & dosificación , Enfermedades de los Gatos/diagnóstico , Enfermedades de los Gatos/tratamiento farmacológico , Enfermedades de los Gatos/patología , Gatos , Eutanasia Animal , Neoplasias Renales/complicaciones , Neoplasias Renales/diagnóstico , Neoplasias Renales/patología , Neoplasias Renales/veterinaria , Linfoma no Hodgkin/complicaciones , Linfoma no Hodgkin/diagnóstico , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/patología , Masculino , Polineuropatía Paraneoplásica/diagnóstico , Polineuropatía Paraneoplásica/etiología , Enfermedades del Sistema Nervioso Periférico/diagnóstico , Enfermedades del Sistema Nervioso Periférico/etiología , Prednisona/administración & dosificación
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