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1.
Toxicol Appl Pharmacol ; 319: 59-68, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28167221

RESUMO

5-Methoxy-2-aminoindane (MEAI) is a psychoactive compound of the aminoindane class, which in recent years has been recreationally used by many people, who reported of a mild euphoric, alcohol-like tipsy experience and reduced desire to consume alcoholic beverages. In the light of these observations it was decided to progress MEAI through a preliminary drug development route and evaluate the acute and subacute toxicity of MEAI administrated orally to Sprague Dawley rats, as well as to determine potential in-vitro cytotoxic and mutagenic effects using state-of-the-art protocols. Furthermore, the interaction of MEAI at the highest non-toxic concentration (100mg/L) with ethanol at cytotoxic levels of 6% and 7.5% was explored, in order to identify possible additive or synergistic effects. MEAI showed a good safety profile in rats at 10 and 30mg/kg body weight, corresponding to the human doses of 1.6mg/kg and 4.8mg/kg body weight, respectively. Cytotoxic effect was demonstrated using concentrations of 500 and 1000mg/L with calculated IC50 value of 368.2mg/L for rat brain striatum primary neurons and 403.1mg/L for human primary healthy hepatocytes. The combination of 6% or 7.5% ethanol with 100mg/L MEAI revealed no statistically significant increase of cytotoxic effect. Further studies, especially long term chronic and addictive behavior studies, are required in-order to assess MEAI safety profile.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas , Peso Corporal/efeitos dos fármacos , Descoberta de Drogas/métodos , Indanos/toxicidade , Animais , Consumo Excessivo de Bebidas Alcoólicas/prevenção & controle , Consumo Excessivo de Bebidas Alcoólicas/psicologia , Peso Corporal/fisiologia , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Hepatócitos/efeitos dos fármacos , Hepatócitos/fisiologia , Humanos , Indanos/química , Indanos/uso terapêutico , Masculino , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Subaguda/métodos
2.
Chem Res Toxicol ; 30(3): 851-858, 2017 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-28125883

RESUMO

Pyrrolizidine alkaloids are among the most common poisonous plants affecting livestock, wildlife, and humans. Exposure of humans and livestock to toxic pyrrolizidine alkaloids through the intake of contaminated food and feed may result in poisoning, leading to devastating epidemics. During February 2014, 73 mixed breed female beef cows from the Galilee region of Israel were accidently fed pyrrolizidine alkaloid contaminated hay for 42 days, resulting in the sudden death of 24 cows over a period of 63 days. The remaining cows were slaughtered 2.5 months after the last ingestion of the contaminated hay. In this study, we report the histopathological analysis of the livers from five of the slaughtered cows and quantitation of pyrrolizidine alkaloid-derived DNA adducts from their livers and three livers of control cows fed with feed free of weeds producing pyrrolizidine alkaloids. Histopathological examination revealed that the five cows suffered from varying degrees of bile duct proliferation, fibrosis, and megalocytosis. Selected reaction monitoring HPLC-ES-MS/MS analysis indicated that (±)-6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine (DHP)-derived DNA adducts were formed in all five livers. The livers from the three control cows did not have any liver damage nor any indication of DHP-DNA adduct formed. These results confirm that the toxicity observed in these cattle was caused by pyrrolizidine alkaloid poisoning and that pyrrolizidine alkaloid-derived DNA adducts could still be detected and quantified in the livers of the chronically poisoned cows 2.5 months after their last exposure to the contaminated feed, suggesting that DHP-derived DNA adducts can serve as biomarkers for pyrrolizidine alkaloid exposure and poisoning.


Assuntos
Adutos de DNA/química , Heliotropium/fisiologia , Fígado/química , Plantas Tóxicas/toxicidade , Alcaloides de Pirrolizidina/química , Animais , Bovinos , Cromatografia Líquida , Fígado/patologia , Espectrometria de Massas em Tandem
3.
Front Neuroanat ; 18: 1383126, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38741761

RESUMO

The topographic anatomy of the abducens nerve has been the subject of research for more than 150 years. Although its vulnerability was initially attributed to its length, this hypothesis has largely lost prominence. Instead, attention has shifted toward its intricate anatomical relations along the cranial base. Contrary to the extensive anatomical and neurosurgical literature on abducens nerve anatomy in humans, its complex anatomy in other species has received less emphasis. The main question addressed here is why the human abducens nerve is predisposed to injury. Specifically, we aim to perform a comparative analysis of the basicranial pathway of the abducens nerve in mammals and primates. Our hypothesis links its vulnerability to cranial base flexion, particularly around the sphenooccipital synchondrosis. We examined the abducens nerve pathway in various mammals, including primates, humans (N = 40; 60% males; 40% females), and human fetuses (N = 5; 60% males; 40% females). The findings are presented at both the macroscopic and histological levels. To associate our findings with basicranial flexion, we measured the cranial base angles in the species included in this study and compared them to data in the available literature. Our findings show that the primitive state of the abducens nerve pathway follows a nearly flat (unflexed) cranial base from the pontomedullary sulcus to the superior orbital fissure. Only the gulfar segment, where the nerve passes through Dorello's canal, demonstrates some degree of variation. We present evidence indicating that the derived state of the abducens pathway, which is most pronounced in humans from an early stage of development, is characterized by following the significantly more flexed basicranium. Overall, the present study elucidates the evolutionary basis for the vulnerability of the abducens nerve, especially within its gulfar and cavernous segments, which are situated at the main synchondroses between the anterior, middle, and posterior cranial fossae-a unique anatomical relation exclusive to the abducens nerve. The principal differences between the pathways of this nerve and those of other cranial nerves are discussed. The findings suggest that the highly flexed human cranial base plays a pivotal role in the intricate anatomical relations and resulting vulnerability of the abducens nerve.

4.
Transl Lung Cancer Res ; 13(1): 60-75, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38404993

RESUMO

Background: Radiotherapy is a standard treatment modality in cancer therapy, particularly for lung cancer. Diffusing alpha-emitters Radiation Therapy sources (hereafter, "Alpha DaRTs") are fixed with Ra-244 (half-life =3.6 days) that releases alpha-emitting atoms into the tumor tissue to an effective range of a few millimeters. Methods: The feasibility, usability, and safety of Alpha DaRTs deployment and implantation via bronchoscopy into the lung parenchyma and mediastinum in a big animal model of healthy swine was studied in two phases: (I) inert and (II) active Alpha DaRTs deployment. The Alpha DaRTs were inserted in both individual and cluster patterns based on a predefined plan. Swine health was monitored throughout the study. The usability of bronchoscopic deployment and implantation was evaluated using a user questionnaire. The movement and migration of the Alpha DaRTs were assessed. Necropsy was performed, and lungs were evaluated via gross pathology and histopathology. Results: A total of 158 Alpha DaRTs were inserted successfully in the lung parenchyma and mediastinum of five swine in two phases. It was possible to deliver and place the Alpha DaRTs in clusters of no more than 4 mm distance between the Alpha DaRTs. No adverse event or change in the health and general condition of animals was observed. Hematologic evaluation did not show any clinically significant abnormality related to the Alpha DaRTs. Histopathology demonstrated local mild inflammatory changes, minimal fibrosis, and dystrophic mineralization with giant cells. Minimal movement and no migration of Alpha DaRTs were observed. Conclusions: Bronchoscopic deployment of Alpha DaRTs in the lung parenchyma and mediastinum of the porcine animal is feasible, precise, and safe.

5.
Parasit Vectors ; 16(1): 337, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752595

RESUMO

BACKGROUND: Borrelia persica causes tick-borne relapsing fever in Israel, the eastern Mediterranean basin, and Asia. Relapsing fever is associated with severe illness and potentially death in humans and animals. Since B. persica infection has rarely been described in wild animals, the aim of this study was to evaluate the prevalence of infection with B. persica in wild carnivores in Israel. METHODS: Spleen and blood clot samples from wild carnivores, which underwent necropsy, were tested for the presence of Borrelia DNA by real-time polymerase chain reaction (PCR). PCR products were sequenced, and the spirochete loads were quantified using a specific quantitative PCR (qPCR). RESULTS: A total of 140 samples from 74 wild carnivores were analyzed for the presence of Borrelia DNA. Six out of the 74 (8.1%) animals were found positive for B. persica by PCR and sequencing of the flagellin B gene, of which 4/74 (5.4%) were also positive by PCR for the glycerophosphodiester phosphodiesterase (glpQ) gene. Positive samples were obtained from three European badgers, and one striped hyena, golden jackal, and red fox each. All B. persica-positive animals were young males (P < 0.0001). Quantifiable results were obtained from 3/5 spleen and 4/5 blood samples. The spirochete loads in the blood were significantly higher than those found in the spleen (P = 0.034). CONCLUSIONS: The prevalence of B. persica infection found in wild carnivores brought for necropsy was unexpectedly high, suggesting that this infection is widespread in some wild animal species in Israel. This is the first report of B. persica infection in the European badger and striped hyena. These carnivores have a wide geographical range of activity, and the results of this survey raise the possibility that they may serve as reservoir hosts for B. persica.


Assuntos
Infecções por Borrelia , Borrelia , Hyaenidae , Mustelidae , Febre Recorrente , Humanos , Masculino , Animais , Israel/epidemiologia , Borrelia/genética , Animais Selvagens , DNA
6.
Microbiol Spectr ; 11(4): e0484822, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37428095

RESUMO

Coronaviruses (CoVs) are enveloped viruses with a large RNA genome (26 to 32 kb) and are classified into four genera: Alphacoronavirus, Betacoronavirus, Gammacoronavirus, and Deltacoronavirus. CoV infections cause respiratory, enteric, and neurologic disorders in mammalian and avian species. In 2019, Oryx leucoryx animals suffered from severe hemorrhagic diarrhea and high morbidity rates. Upon initial diagnosis, we found that the infected animals were positive for coronavirus by pancoronavirus reverse transcriptase RT-PCR. Next, we detected the presence of CoV particles in these samples by electron microscopy and immunohistochemistry. CoV was isolated and propagated on the HRT-18G cell line, and its full genome was sequenced. Full-genome characterization and amino acid comparisons of this viral agent demonstrated that this virus is an evolutionarily distinct Betacoronavirus belonging to the subgenus Embecovirus and the Betacoronavirus 1 species. Furthermore, we found that it is most similar to the subspecies dromedary camel coronavirus HKU23 by phylogenetic analysis. Here, we present the first report of isolation and characterization of Betacoronavirus associated with enteric disease in Oryx leucoryx. IMPORTANCE CoVs cause enteric and respiratory infections in humans and animal hosts. The ability of CoVs to cross interspecies barriers is well recognized, as emphasized by the ongoing pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The identification of novel CoV strains and surveillance of CoVs in both humans and animals are relevant and important to global health. In this study, we isolated and characterized a newly identified Betacoronavirus that causes enteric disease in a wild animal, Oryx leucoryx (the Arabian oryx). This work is the first report describing CoV infection in Oryx leucoryx and provides insights into its origin.


Assuntos
COVID-19 , Animais , Humanos , Filogenia , SARS-CoV-2 , Animais Selvagens , Aves , Mamíferos
7.
Viruses ; 13(3)2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806696

RESUMO

During 2019, five carcasses of juvenile Egyptian fruit bats (Rousettus aegyptiacus) were submitted to the Kimron Veterinary Institute. These bats exhibited typical poxvirus like lesion plaques of different sizes on the skin, abdomen and the ventral side of the wings. Clinical and histopathological findings suggested a poxvirus infection. Infectious virus was isolated from skin swabs, skin tissue and tongue of the dead bats and was further confirmed to be a Poxvirus by molecular diagnosis using PCR with pan-chordopoxviruses primers. All the dead bats were found positive for two Poxvirus genes encoding a metalloproteinase and DNA dependent DNA polymerase. In this study, a novel real time quantitative PCR (qPCR) assay was established to further confirmed the presence of specific poxvirus viral DNA in all pathologically tested tissues. Moreover, according to sequence analysis, the virus was found to be highly similar to the recently discovered Israeli Rousettus aegyptiacus Pox Virus (IsrRAPXV).


Assuntos
Quirópteros/virologia , DNA Viral/isolamento & purificação , Infecções por Poxviridae/virologia , Poxviridae/isolamento & purificação , Animais
8.
Dis Model Mech ; 14(3)2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33608323

RESUMO

Fatty liver is an abnormal metabolic condition of excess intrahepatic fat. This condition, referred to as hepatic steatosis, is tightly associated with chronic liver disease and systemic metabolic morbidity. The most prevalent form in humans, i.e. non-alcoholic fatty liver, generally develops due to overnutrition and sedentary lifestyle, and has as yet no approved drug therapy. Previously, we have developed a relevant large-animal model in which overnourished sheep raised on a high-calorie carbohydrate-rich diet develop hyperglycemia, hyperinsulinemia, insulin resistance, and hepatic steatosis. Here, we tested the hypothesis that treatment with thiamine (vitamin B1) can counter the development of hepatic steatosis driven by overnutrition. Remarkably, the thiamine-treated animals presented with completely normal levels of intrahepatic fat, despite consuming the same amount of liver-fattening diet. Thiamine treatment also decreased hyperglycemia and increased the glycogen content of the liver, but it did not improve insulin sensitivity, suggesting that steatosis can be addressed independently of targeting insulin resistance. Thiamine increased the catalytic capacity for hepatic oxidation of carbohydrates and fatty acids. However, at gene-expression levels, more-pronounced effects were observed on lipid-droplet formation and lipidation of very-low-density lipoprotein, suggesting that thiamine affects lipid metabolism not only through its known classic coenzyme roles. This discovery of the potent anti-steatotic effect of thiamine may prove clinically useful in managing fatty liver-related disorders.This article has an associated First Person interview with the joint first authors of the paper.


Assuntos
Fígado Gorduroso/etiologia , Fígado Gorduroso/prevenção & controle , Hipernutrição/complicações , Tiamina/administração & dosagem , Tiamina/uso terapêutico , Adiposidade , Animais , Glicemia/metabolismo , Citocinas/metabolismo , Dieta Hiperlipídica , Relação Dose-Resposta a Droga , Ácidos Graxos/metabolismo , Fígado Gorduroso/sangue , Fígado Gorduroso/tratamento farmacológico , Regulação da Expressão Gênica , Glicogênio/metabolismo , Mediadores da Inflamação/metabolismo , Complexo Cetoglutarato Desidrogenase/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Mitocôndrias/metabolismo , Hipernutrição/sangue , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ovinos , Tiamina Pirofosfato/metabolismo , Aumento de Peso
9.
Pathogens ; 10(2)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572875

RESUMO

Bovine babesiosis, caused by Babesia bovis and B. bigemina, is a major tick-borne disease of cattle with global economic impact. The disease can be prevented using integrated control measures including attenuated Babesia vaccines, babesicidal drugs, and tick control approaches. Vaccination of cattle with the Rhipicephalus microplus Bm86-based recombinant vaccine reduces the fitness of R. microplus and R. annulatus, but several booster inoculations are required to maintain protection. Herein, we generated a stable transfected strain of B. bovis expressing an enhanced GFP (eGFP) and a chimeric version of Bm86 (B. bovis/Bm86/eGFP). The eGFP was expressed in the parasite cytoplasm, whereas Bm86 was displayed on the surface of merozoites. Three splenectomized calves experimentally infected with B. bovis/Bm86/eGFP showed mild signs of acute disease and developed long-lasting antibody responses to B. bovis and native Bm86. No evidence of sequestration of parasites in the cerebral capillaries was found upon postmortem analysis, confirming attenuation of the strain. This is the first report of transfected B. bovis expressing the tick antigen Bm86 on the merozoite surface that elicits an antibody response to native Bm86. These results represent a proof of concept for a novel live, attenuated, tagged dual-vaccine approach to attempt simultaneous control of babesiosis and tick infestation.

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