Panayiotis Loukopoulos - Academia.edu (original) (raw)

Papers by Panayiotis Loukopoulos

Social Science Research Network, 2018

We investigate how the realignment in political landscape (local policy risk) increases IPO mispr... more We investigate how the realignment in political landscape (local policy risk) increases IPO mispricing. Using the concept of corporate proximity to political power, we find that local policy risk amplifies adverse selection problems, which leads to higher underpricing. Economically, a shift on the political map from an area completely opposed to the ruling party to being completely aligned translates to $12 million left on the table for the average issuer. While politically active firms successfully manage this policy realignment risk, the other firms bear majority of its consequences. We also demonstrate considerable heterogeneity on the impact of uncertainty emanating from the dynamic nature of the political landscape across industries, states, and firms. Lastly, we document that policy risk has a substantial adverse impact on the survival of IPO issuers.

Journal of Animal and Veterinary Advances, 2004

Up to 500 species of Panicum (panic grasses) are recognised worldwide, of which 24 species are in... more Up to 500 species of Panicum (panic grasses) are recognised worldwide, of which 24 species are indigenous to Australia and nine introduced. Recently, some of the introduced summer-growing annual Panicum spp. have been identified with high prevalence across southern Australia. Certain Panicum species have also been implicated in severe outbreaks of hepatogenous photosensitization in livestock, characterized by crystal-associated cholangiohepatopathy. The causal compound(s) responsible for liver dysfunction in livestock ingesting Panicum spp. have been previously identified as steroidal saponins. Although metabolic profiling of Panicum spp. has been undertaken in the USA and NZ, the saponins implicated in toxic outbreaks in Australia have not yet been identified. In this study, fresh shoot tissue from three introduced (P. capillare,P. hillmanii and P. gilvum) and two native (P. decompositumand P. effusum) species were extracted in methanol and analysed by UPLC/QTOF mass spectrometry. The relative abundance of key steroidal saponins was determined based on specific molecular features including retention time, mass spectra and fragmentation pattern when compared to saponin analytical standards. Distinct qualitative and quantitative differences were observed in the saponin profiles of the Panicum species evaluated, including in the type, number and abundance of the saponins detected, such as protodioscin and pseudoprotodioscin.. In vitro cytotoxicity assays of shoot extracts collected from Panicumrelated photosensitization outbreaks will be performed to further identify key steroidal saponins and saponin profiles associated with hepatogenous photosensitization in grazing livestock

ABSTRACT Un guacamayo militar (Ara militaris), hembra, de ocho años de edad y 700 gr, presentó le... more ABSTRACT Un guacamayo militar (Ara militaris), hembra, de ocho años de edad y 700 gr, presentó letargia y biliverdinuria luego de sufrir episodios recurrentes de leucocitosis durante el último año. A pesar de la administración de doxiciclina, nistatina y fluconazol, se observó el desmejoramiento del ave durante una semana. En ese momento, la técnica de inmunofluorescencia indirecta fue negativa para Chlamydia spp. y el animal presentó leucocitosis severa y ácidos biliares y AST elevados. Debido al mal pronóstico clínico, se realizó eutanasia. A la necropsia, se observó hepatomegalia y esplenomegalia con nódulos blanquecinos de 1 a 2 mm de diámetro en ambos órganos y el proventrículo se observó marcadamente distendido. Microscópicamente, la mayoría del parénquima hepático se observó reemplazado por granulomas coalescentes de 50 a 300 μm de diámetro cuyos centros estaban compuestos por macrófagos espumosos o por material hipereosinofílico amorfo y restos celulares cariorrécticos junto con linfocitos y macrófagos espumosos. Estos centros estaban circundados por macrófagos epiteloides, células gigantes multinucleadas y escasos linfocitos y células plasmáticas y fibrosis. Los macrófagos, macrófagos epiteloides, y en menor medida los hepatocitos, presentaban bacilos cortos débilmente teñidos con hematoxilina y eosina en su interior. Entre los granulomas, se observaron cordones hepáticos desorganizados, con pérdidas de hepatocitos y áreas de fibrosis leve. El bazo presentó granulomas similares a los del hígado. Además, se destacaron infiltraciones linfocíticas y plasmocíticas, severas, en los plexos mioentéricos del buche, estómago glandular, intestino delgado y ciegos, neuritis linfocítica y plasmocítica en los senos paranasales, leve y multifocal y ganglioneuritis linfocítica y plasmocítica, moderada, en el corazón. La tinción de Ziehl-Neelsen modificada reveló la presencia de pequeños bacilos ácido-alcohol resistentes intracelulares en macrófagos en hígado y bazo. La tinción de Giménez no demostró la presencia de microorganismos. Las inmunohistoquímica (IHQ) para Chlamydia spp. fue negativa en ambos órganos. Se observaron resultados negativos en los cultivos bacteriológicos aeróbicos de hígado y pulmones, en la detección del virus del Nilo Occidental usando IHQ, en las detecciones de Salmonella spp., Mycobacterium genavense e influenza aviar utilizando PCR y en la observación de partículas virales en materia fecal usando microscopía electrónica. Los plexos mioentéricos del buche, estómago glandular e intestino delgado resultaron positivos para bornavirus aviar por medio de IHQ. Mycobacterium avium subsp. hominissuis fue aislado a partir del hígado e identificado como el agente etiológico causal. El aislamiento de M. avium subsp. hominissuis fue secuenciado en las regiones 16S rARN y rpoB de su genoma. La secuencia de genes fue comparada con aquellas presentes en el GenBank y se encontró que presentó un 100% de similitud con ellas. Los hallazgos anatomopatológicos y microbiológicos confirmaron un diagnóstico de micobacteriosis sistémica concurrente con enfermedad de dilatación proventricular (EDP). Un estudio retrospectivo de 123 casos en psitácidos concluyó que M. avium subsp. avium y M. genavense actuaron como los agentes causales intervinientes. La infección producida por M. avium subsp. hominissuis es encontrada principalmente en cerdos y humanos. Sin embargo, durante los últimos años, también fueron reportados casos en perros, caballos, burros asiáticos salvajes, jabalíes y antílopes africanos. A pesar que la secuenciación genómica de M. avium subsp. hominissuis se logró a partir de un aislamiento de un ave paserina de la familia Eurylaimidae, la infección causada por M. avium subsp. hominissuis en aves fue descripta únicamente en un psitácido Amazona de frente azul (Amazona aestiva) mascota en 2009. Debido a que M. avium subsp. hominissuis fue propuesta como una nueva subespecie en 2002, se presume que su prevalencia podría ser mayor a la reportada hasta el momento. En el presente caso, se conjetura que la EDP concurrente a la micobacteriosis sistémica pudo haber contribuido al deterioro del psitácido.

An association between abortion and low selenium (Se) status in cattle has been suspected, but no... more An association between abortion and low selenium (Se) status in cattle has been suspected, but not confirmed previously. Abortion outbreaks in 3 Se-deficient beef cattle herds, between 2010 and 2013, are described. In total, 130 out of the 480 cattle aborted (27.1%): among these, 28/130 (21.5%) abortions were in herd 1, 47/150 (31.3%) in herd 2 and 55/200 (27.5%) in herd 3. Five aborted fetuses were examined grossly and histopathologically. Laboratory examinations for bacterial, viral and parasitic causes of abortions were conducted (fetuses, fetal membranes, cows' blood) and were found negative. Moreover, blood samples from 18 aborting cows were examined for Se, vitamin A and vitamin E concentrations. Blood Se levels in cows belonging to farms that experienced abortions were lower than reference values and significantly lower than 28 control cows from 3 herds without abortions (0.46±0.08 vs. 2.20±0.04 μmol/L; P<0.0001). Serum vitamin E and vitamin A concentrations were within reference range and did not differ from controls. Skeletal muscle and myocardial degeneration and atrophy were observed in 5 aborted calves. Abortions were significantly reduced from 26% to 1.1% following the subcutaneous administration of a Se and vitamin E containing commercial preparation to each of the remaining pregnant cows, at a dose 0.1 mg/kg body weight for Se and 8.98 mg/kg body weight for vitamin E. In conclusion, determination of whole blood Se status before late gestation is useful in early diagnosis of Se deficiency and should be included in the diagnostic panel when investigating abortions in cattle.

Journal of the Hellenic Veterinary Medical Society, Dec 20, 2017

Μελέτη της επίδρασης της Nigella sativa σε αρουραίους, στους οποίους είχε προκληθεί πειραματικά κ... more Μελέτη της επίδρασης της Nigella sativa σε αρουραίους, στους οποίους είχε προκληθεί πειραματικά καρκίνος του ήπατος μετά από χορήγηση διεθυλονιτροζαμίνης

Australian Veterinary Journal, Nov 1, 2019

This article is protected by copyright. All rights reserved. This is the author manuscript accept... more This article is protected by copyright. All rights reserved. This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as

A 14-month-old golden retriever was presented with progressive right front limb lameness of 1.5 m... more A 14-month-old golden retriever was presented with progressive right front limb lameness of 1.5 months' duration caused by a large spherical mass in the right scapula. Radiographic examination was consistent with skeletal neoplasia, showing a distinctive area of osteolytic and osteogenic activity, adjacent soft tissue invasion and metastatic lesions in the anterior lung fields. The histopathologic examination established the diagnosis of minimally productive, osteoblastic, grade III osteosarcoma. Both scapular osteosarcomas and osteosarcomas in very young dogs are rarely described; to the best of our knowledge, scapular osteosarcomas have not been described at such a young age previously.

Equine Veterinary Education, Dec 17, 2015

This paper describes the occurrence of a lipoma associated with the long digital extensor tendon ... more This paper describes the occurrence of a lipoma associated with the long digital extensor tendon sheath at the level of the tarsus in a 5-month-old female Thoroughbred. Radiographic and ultrasonographic images were interpreted as being an atypically located lipoma. Its position and character have some similarities to lipoma arborescens, which is reported to occur in and around human joints and tendon sheaths. Surgical removal is considered to be the treatment of choice.