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1.
Plants (Basel) ; 13(14)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39065478

RESUMO

There are inconclusive claims in the scientific literature that the species Trema micranthum, widely distributed throughout the Brazilian territory, may produce phytocannabinoids, potentially serving as an alternative to Cannabis sativa. In this study, we conducted a comprehensive investigation to assess the presence of phytocannabinoids in two Trema micranthum samples collected in the Midwest region of Brazil. In trying to detect cannabinoids in T. micranthum, a recommended cannabis screening test was employed, the Fast Blue BB Salt (FBBBS) colorimetric assay, followed by thin-layer chromatography (TLC) and instrumental techniques: high-performance liquid chromatography coupled to diode array detector (HPLC-DAD) and gas chromatography coupled to mass spectrometry (GC-MS). When employed without chloroform extraction, the FBBBS reagent yielded positive results for extracts from all parts of T. micranthum (leaves, branches, fruits, and inflorescences). However, these initial positive results from the FBBBS test, suggesting the presence of cannabinoids, were not corroborated by FBBBS followed by chloroform extraction, TLC, or the instrumental techniques used in this study. These additional outcomes suggest that the positive FBBBS test results were likely due to the presence of other phenolic compounds rather than phytocannabinoids. For example, the presence of vitexin-like compounds in T. micranthum extracts might explain the positive FBBBS test results. Therefore, new assertions that T. micranthum produces cannabinoids will require the support of more selective experiments to avoid false-positive claims based on less selective screening tests.

2.
Semina ciênc. agrar ; 43(3): 1373-1394, maio.-jun. 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1369587

RESUMO

Hop (Humulus lupulus L.) female inflorescences are important raw materials used to produce beers, cosmetics, and medicines. Vegetative propagation is the preferred way of obtaining seedlings for commercial cultivations as female plants produce more lupulin than male plants, a component of commercial interest. It can be carried out by macropropagation (stem cuttings or rhizomes) or micropropagation. This review aimed to systematize different techniques of hop vegetative propagation, with no time frame, from searches in the main academic research bases: Capes Journal Portal, Scielo, Scopus, Web of Science, Science Direct, Google Scholar, and ResearchGate. Most studies are related to micropropagation, mainly addressing different plant regulators and concentrations, as well as types of explants and culture media, strategies to produce virus-free plants, artificial lighting, and cryopreservation. Experiments with stem cuttings are more common regarding macropropagation, but factors such as size and origin of cuttings, rooting period, and the response of different cultivars need to be better evaluated. Cultivation by cuttings allows the production of clones of female plants and micropropagation the production of virus-free clones in a short time and less physical space. Currently, micropropagation has been widely applied to cryopreservation.(AU)


As inflorescências femininas do lúpulo (Humulus lupulus L.) são matérias-primas importantes utilizadas na produção de cervejas, cosméticos e medicamentos. Como as plantas femininas produzem mais lupulina que as masculinas, componente de interesse comercial, a propagação vegetativa é a forma preferencial de obtenção de mudas para os cultivos comerciais. Esta pode ser realizada por macropropagação (estaquia caulinar ou rizomas) ou micropropagação. O objetivo desta revisão foi sistematizar as diferentes técnicas de propagação vegetativa do lúpulo, sem recorte temporal, a partir de buscas nas principais bases de pesquisa acadêmica: Portal de Periódicos Capes, Scielo, Scopus, Web of Science, Science Direct, Google Acadêmico e Research Gate. A maioria dos trabalhos são relacionados à micropropagação, abordando principalmente diferentes reguladores vegetais e concentrações, além de tipos de explantes e meios de cultura, estratégias para produzir plantas livres de vírus, iluminação artificial e criopreservação. Quanto à macropropagação, experimentos com estaquia caulinar são mais comuns, porém fatores precisam ser melhor avaliados tais como tamanho e origem das estacas, período de enraizamento e resposta de diferentes cultivares. O cultivo por estacas permite a produção de clones de plantas femininas e a micropropagação a produção de clones isentos de vírus, em pouco tempo e em menor espaço físico. Atualmente, a micropropagação tem sido muito aplicada à criopreservação.(AU)


Assuntos
Humulus/crescimento & desenvolvimento , Rizoma , Inflorescência , Cannabaceae/crescimento & desenvolvimento , História
3.
Am J Bot ; 108(9): 1595-1611, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34478152

RESUMO

PREMISE: Celtis is the most species-rich genus of Cannabaceae, an economically important family. Celtis species have been described as wind-pollinated and andromonoecious. However, the andromonoecy of Celtis has been debated because there are reports of monoclinous flowers with non-opening anthers on short filaments. Our objective was to study the floral morphogenesis of Celtis to establish the breeding system and to better understand the developmental patterns that lead to the formation of reduced flowers in the genus. METHODS: Flowers and floral buds of Celtis species were studied using scanning electron microscopy, high-resolution x-ray computed tomography, and light microscopy. RESULTS: All flowers initiate stamens and carpels during early floral development, but either stamens or carpels abort during later stages. Thus, at anthesis, flowers are either functionally pistillate or functionally staminate. In pistillate flowers, stamens abort late and become staminodes with normal-looking anthers. These anthers have no functional endothecium and, in most of the species studied, produce no viable pollen grains. The gynoecium is pseudomonomerous, and its vascularization is similar in the sampled species. In staminate flowers, the gynoecium aborts early resulting in small pistillodes. No vestiges of petals were found. CONCLUSIONS: The species studied are monoecious and not andromonoecious as described earlier. The absence of petals, the carpel and stamen abortion, and the pseudomonomerous gynoecium result in the reduced flowers of Celtis species. The use of high-resolution x-ray computed tomography was essential for a more accurate interpretation of ovary vascularization, confirming the pseudomonomerous structure of the gynoecium.


Assuntos
Cannabaceae , Ulmaceae , Flores , Morfogênese , Melhoramento Vegetal
4.
Am J Bot ; 106(3): 489-506, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30875436

RESUMO

PREMISE OF THE STUDY: This study details the unusual synorganization of the staminate flower in wind-pollinated urticalean rosids to add the missing pieces that complete the puzzle of the explosive mechanism of pollen release in this group. METHODS: Flower buds and flowers were analyzed using light and scanning electron microscopy. KEY RESULTS: The pistillode, stamens, and sepals form a floral apparatus that explosively releases pollen to be carried by the wind. The anthers dehisce when the stamens are still inflexed on the floral bud and are enveloped by the sepals and supported by an inflated pistillode. The distension of the filaments presses the pistillode, which decreases the pressure exerted on the anthers by releasing the air accumulated internally through its apical orifice. The extended filaments and the dehiscent free anthers move rapidly outward from the center of the flower. This movement of the filaments is then blocked by the robust basally united sepals, which causes a rapid inversion of the anther position, thus hurling the pollen grains far from the flower. The pollen grains are released grouped by the mucilage produced in high quantity in the cells found in all floral organs. CONCLUSIONS: The anatomical structure of the pistillode and the finding of mucilaginous cells are the main features that help in the understanding the explosive mechanism of pollen release in urticalean rosids. The pistillode can be considered an exaptation because it was evolved later to provide a new role in the plant, optimizing male fitness.


Assuntos
Cannabaceae/anatomia & histologia , Flores/anatomia & histologia , Moraceae/anatomia & histologia , Polinização , Urticaceae/anatomia & histologia , Cannabaceae/fisiologia , Flores/fisiologia , Moraceae/fisiologia , Urticaceae/fisiologia , Vento
5.
Equine Vet J ; 50(2): 192-195, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28805273

RESUMO

BACKGROUND: Trema micrantha is a tree widely distributed throughout the Americas. The tree produces highly palatable leaves that have been associated with natural poisoning in goats, sheep and horses, in which hepatic necrosis and hepatic encephalopathy have been observed. OBJECTIVES: This study describes malacia and haemorrhage in the central nervous system (CNS) due to T. micrantha consumption, with minimal to absent hepatic lesions. STUDY DESIGN: Retrospective case series. METHODS: A total of 14 horses with a history of neurological signs and spontaneous consumption of T. micrantha leaves were submitted to necropsy and multiple samples were collected for histopathology. Details of clinical history and signs of the horses were obtained through inquiries to the owners and attending veterinarians. RESULTS: All the 14 horses had neurological signs of ataxia, severe sialorrhoea, involuntary running movements, sternal and lateral recumbency, and death after a clinical course that lasted from 24 h to 9 days. For a few days prior to onset of clinical signs, all horses had spontaneously consumed, potentially toxic doses of T. micrantha leaves. All 14 brains had diffuse yellowish discoloration affecting the rhombencephalon, mesencephalon, diencephalon, telencephalon and corpus striatum. In all cases, the most severe lesions were observed in the pons. Spinal cord lesions were observed affecting the lumbar intumescence, which was swollen with darken and depressed areas at the dorsal and ventral horns, and at the sacral level, which on cut surface displayed a friable and yellowish grey matter. The lesions observed grossly in brain and spinal cord consisted microscopically of severe vasculitis and liquefactive necrosis of white and grey matter of the brainstem, cerebellum and spinal cord. MAIN LIMITATIONS: This is a small retrospective series relying on clinical observations reported by owners and attending veterinarians. The mechanism of action of the plant toxin in the CNS is still unidentified. CONCLUSION: T. micrantha poisoning in horses causes predominantly a neurological disease, with minimal to absent hepatic lesions.


Assuntos
Doenças do Sistema Nervoso Central/veterinária , Doenças dos Cavalos/induzido quimicamente , Intoxicação por Plantas/veterinária , Plantas Tóxicas/toxicidade , Trema , Animais , Doenças do Sistema Nervoso Central/induzido quimicamente , Doenças do Sistema Nervoso Central/patologia , Doenças dos Cavalos/mortalidade , Doenças dos Cavalos/patologia , Cavalos , Intoxicação por Plantas/patologia , Estudos Retrospectivos
6.
Pesqui. vet. bras ; 33(11): 1339-1344, nov. 2013. ilus
Artigo em Português | VETINDEX | ID: vti-10014

RESUMO

Trema micrantha é uma planta arbórea distribuída amplamente no Brasil. Descrevem-se nesse trabalho novos aspectos epidemiológicos e patológicos relacionados com a intoxicação por essa planta em equídeos. Dois equinos adultos da raça Crioula e dois asininos, de localidades distintas, foram intoxicados naturalmente por Trema micrantha, após consumirem grande quantidade da planta que ficou disponível a eles após uma poda. Além disso, um cavalo adulto, de outra propriedade, que estava passando por restrição alimentar, se intoxicou após consumir as partes baixas de um grande número de árvores jovens de T. micrantha. Clinicamente, em todos os equídeos a doença se caracterizou por alterações neurológicas, que apareceram três a quatro dias após o consumo da planta, com curso clínico de dois a quatro dias (abreviadas por eutanásia). Os principais achados de necropsia foram observados no fígado, que estavam levemente aumentados e com padrão lobular evidente e no sistema nervoso central (SNC), com múltiplas áreas amareladas, focos de malacia e hemorragia, principalmente, no tronco cerebral e cerebelo. Histologicamente, havia necrose hepática aguda, edema acentuado no SNC com degeneração fibrinoide da parede de vasos associada a hemorragia e trombose e, frequentemente, com infiltrado de neutrófilos. Outras alterações observadas nos encéfalos foram: grande quantidade de astrócitos de Alzheimer tipo II na substância cinzenta, acúmulos de células Gitter e degeneração Walleriana próxima a focos de lesões vasculares. (AU)


Trema micrantha is a tree widely distributed in Brazil. This paper describes new epidemiological and pathological aspects of this plant poisoning in equids. Two adult horses, Criollo breed and two donkeys from different locations were naturally poisoned by Trema micrantha after consuming large amounts of the plant which was available to them due to pruning. Also an adult horse from another ranch, which was undergoing dietary restriction, was poisoned after consuming the lower parts of a large number of young T. micrantha trees. Clinically, in all cases, the disease was characterized by neurological symptoms that started 3 to 4 days after consumption of the plant, with a clinical course that varied 2 to 4 days (abbreviated by euthanasia). The main gross findings were in the liver, which had slightly increased lobular pattern evident, and in the central nervous system (CNS) with multiple yellowish areas, foci of malacia and hemorrhage, especially in the brainstem and cerebellum. Histologically, there was acute liver necrosis with marked edema of the CNS with fibrinoid vessel wall degeneration, hemorrhage and thrombosis as well as neutrophil infiltration. Other changes in the brain were Alzheimer type II astrocytes in the gray matter, accumulation of Gitter cells and Wallerian degeneration near to vascular lesion foci. (AU)


Assuntos
Animais , Equidae/fisiologia , Trema/toxicidade , Plantas Tóxicas/intoxicação , Intoxicação por Plantas/epidemiologia , Intoxicação por Plantas/veterinária
7.
Pesqui. vet. bras ; Pesqui. vet. bras;33(11): 1339-1344, Nov. 2013. ilus
Artigo em Português | LILACS | ID: lil-697880

RESUMO

Trema micrantha é uma planta arbórea distribuída amplamente no Brasil. Descrevem-se nesse trabalho novos aspectos epidemiológicos e patológicos relacionados com a intoxicação por essa planta em equídeos. Dois equinos adultos da raça Crioula e dois asininos, de localidades distintas, foram intoxicados naturalmente por Trema micrantha, após consumirem grande quantidade da planta que ficou disponível a eles após uma poda. Além disso, um cavalo adulto, de outra propriedade, que estava passando por restrição alimentar, se intoxicou após consumir as partes baixas de um grande número de árvores jovens de T. micrantha. Clinicamente, em todos os equídeos a doença se caracterizou por alterações neurológicas, que apareceram três a quatro dias após o consumo da planta, com curso clínico de dois a quatro dias (abreviadas por eutanásia). Os principais achados de necropsia foram observados no fígado, que estavam levemente aumentados e com padrão lobular evidente e no sistema nervoso central (SNC), com múltiplas áreas amareladas, focos de malacia e hemorragia, principalmente, no tronco cerebral e cerebelo. Histologicamente, havia necrose hepática aguda, edema acentuado no SNC com degeneração fibrinoide da parede de vasos associada a hemorragia e trombose e, frequentemente, com infiltrado de neutrófilos. Outras alterações observadas nos encéfalos foram: grande quantidade de astrócitos de Alzheimer tipo II na substância cinzenta, acúmulos de células Gitter e degeneração Walleriana próxima a focos de lesões vasculares.


Trema micrantha is a tree widely distributed in Brazil. This paper describes new epidemiological and pathological aspects of this plant poisoning in equids. Two adult horses, Criollo breed and two donkeys from different locations were naturally poisoned by Trema micrantha after consuming large amounts of the plant which was available to them due to pruning. Also an adult horse from another ranch, which was undergoing dietary restriction, was poisoned after consuming the lower parts of a large number of young T. micrantha trees. Clinically, in all cases, the disease was characterized by neurological symptoms that started 3 to 4 days after consumption of the plant, with a clinical course that varied 2 to 4 days (abbreviated by euthanasia). The main gross findings were in the liver, which had slightly increased lobular pattern evident, and in the central nervous system (CNS) with multiple yellowish areas, foci of malacia and hemorrhage, especially in the brainstem and cerebellum. Histologically, there was acute liver necrosis with marked edema of the CNS with fibrinoid vessel wall degeneration, hemorrhage and thrombosis as well as neutrophil infiltration. Other changes in the brain were Alzheimer type II astrocytes in the gray matter, accumulation of Gitter cells and Wallerian degeneration near to vascular lesion foci.


Assuntos
Animais , Equidae/fisiologia , Intoxicação por Plantas/epidemiologia , Plantas Tóxicas/intoxicação , Trema/toxicidade , Intoxicação por Plantas/veterinária
8.
Pesqui. vet. bras ; 31(11): 991-996, 2011. ilus, tab
Artigo em Português | VETINDEX | ID: vti-1370

RESUMO

O objetivo desse estudo foi confirmar a toxidez e caracterizar os aspectos clínicos e patológicos da intoxicação por Trema micrantha em equinos. Três equinos, pôneis, com idade entre 2 e 7 anos consumiram espontaneamente folhas de T. micrantha em doses únicas de 30g/kg, 25g/ kg e 20g/kg. Os três animais adoeceram e evoluíram para morte. Outro equino recebeu 15 e 25g/kg da planta com intervalo de 30 dias entre as doses e não apresentou alteração clínica. Coletas diárias de sangue foram realizadas para análises bioquímicas. Os principais sinais clínicos apresentados foram apatia, desequilíbrios, dificuldade de deglutição, decúbito esternal, decúbito lateral, movimentos de pedalagem, coma e morte. Os três equinos afetados apresentaram elevação da atividade sérica de gama-glutamil transferase, dos níveis séricos de amônia e diminuição da glicemia. Esses animais foram necropsiados e fragmentos de diversos órgãos foram coletados para análise histopatológica e imuno-histoquímica. Os principais achados patológicos foram encontrados no fígado e no encéfalo dos três animais. O fígado apresentava, macroscopicamente, acentuação do padrão lobular; enquanto que, no encéfalo havia áreas amareladas na superfície de corte, mais evidentes na substância branca do cerebelo. Microscopicamente, o fígado apresentava tumefação hepatocelular, necrose de coagulação predominantemente centrolobular e hemorragia associada. No encéfalo, havia edema perivascular generalizado e astrócitos Alzheimer tipo II na substância cinzenta. Esses astrócitos apresentaram marcação fraca ou negativa na imuno-histoquímica anti-GFAP e marcação positiva do antígeno S-100. A dose letal mínima de folhas de T. micrantha estabelecida nesse experimento foi de 20g/kg. A ampla distribuição e palatabilidade desta planta, associadas à alta sensibilidade da espécie equina, constatada nesse experimento, reforçam a importância da planta em casos acidentais de intoxicação em equinos.(AU)


The aim of this study was to confirm the toxicity and characterize the clinical and pathological aspects of poisoning by Trema micrantha in horses. The green leaves of the plant were spontaneously consumed by three ponies at single doses of 20, 25, and 30g/kg. The three ponies developed clinical disease characterized by apathy, equilibrium deficit, deglutition difficulty, sternal or lateral recumbency, paddling, coma and death. Affected ponies had also enhanced seric activity of gamma-glutamyl transferase, seric ammonia apart of diminished glycemia. An additional pony, that received 15 and 25g/kg of T. micrantha with a 30 day interval between the two doses, showed no clinical disease. The three ponies were necropsied and fragments from organs were collected for histology and immunostaining (IS) procedures. The main pathological findings were in the liver and encephalon. There were enhanced lobular pattern of the liver and yellowish areas in the cut surface of the encephalon, especially visualized in the cerebellar white matter. Microscopically, there was hepatocellular swelling and coagulative hepatic necrosis predominantly centrilobular with hemorrhages. Generalized perivascular edema and Alzheimer type II astrocytes were observed in the encephalon. The Alzheimer type II astrocytes showed weak or absent anti-glial fibrillar acid protein IS associated with positive IS for S-100 protein. The minimal lethal dose of Trema micrantha leaves was established at 20g/kg. The sensibility of horses to this plant, its wide distribution and high palatability reinforces the importance of Trema micrantha in accidental poisoning of horses.(AU)


Assuntos
Animais , Intoxicação por Plantas/veterinária , Trema/toxicidade , Necrose Hepática Massiva/veterinária , Encefalopatia Hepática/veterinária , Cavalos/anatomia & histologia , Intoxicação por Plantas/fisiopatologia
9.
Pesqui. vet. bras ; Pesqui. vet. bras;31(11): 991-996, Nov. 2011. ilus, tab
Artigo em Português | LILACS | ID: lil-608538

RESUMO

O objetivo desse estudo foi confirmar a toxidez e caracterizar os aspectos clínicos e patológicos da intoxicação por Trema micrantha em equinos. Três equinos, pôneis, com idade entre 2 e 7 anos consumiram espontaneamente folhas de T. micrantha em doses únicas de 30g/kg, 25g/ kg e 20g/kg. Os três animais adoeceram e evoluíram para morte. Outro equino recebeu 15 e 25g/kg da planta com intervalo de 30 dias entre as doses e não apresentou alteração clínica. Coletas diárias de sangue foram realizadas para análises bioquímicas. Os principais sinais clínicos apresentados foram apatia, desequilíbrios, dificuldade de deglutição, decúbito esternal, decúbito lateral, movimentos de pedalagem, coma e morte. Os três equinos afetados apresentaram elevação da atividade sérica de gama-glutamil transferase, dos níveis séricos de amônia e diminuição da glicemia. Esses animais foram necropsiados e fragmentos de diversos órgãos foram coletados para análise histopatológica e imuno-histoquímica. Os principais achados patológicos foram encontrados no fígado e no encéfalo dos três animais. O fígado apresentava, macroscopicamente, acentuação do padrão lobular; enquanto que, no encéfalo havia áreas amareladas na superfície de corte, mais evidentes na substância branca do cerebelo. Microscopicamente, o fígado apresentava tumefação hepatocelular, necrose de coagulação predominantemente centrolobular e hemorragia associada. No encéfalo, havia edema perivascular generalizado e astrócitos Alzheimer tipo II na substância cinzenta. Esses astrócitos apresentaram marcação fraca ou negativa na imuno-histoquímica anti-GFAP e marcação positiva do antígeno S-100. A dose letal mínima de folhas de T. micrantha estabelecida nesse experimento foi de 20g/kg. A ampla distribuição e palatabilidade desta planta, associadas à alta sensibilidade da espécie equina, constatada nesse experimento, reforçam a importância da planta em casos acidentais de intoxicação em equinos.


The aim of this study was to confirm the toxicity and characterize the clinical and pathological aspects of poisoning by Trema micrantha in horses. The green leaves of the plant were spontaneously consumed by three ponies at single doses of 20, 25, and 30g/kg. The three ponies developed clinical disease characterized by apathy, equilibrium deficit, deglutition difficulty, sternal or lateral recumbency, paddling, coma and death. Affected ponies had also enhanced seric activity of gamma-glutamyl transferase, seric ammonia apart of diminished glycemia. An additional pony, that received 15 and 25g/kg of T. micrantha with a 30 day interval between the two doses, showed no clinical disease. The three ponies were necropsied and fragments from organs were collected for histology and immunostaining (IS) procedures. The main pathological findings were in the liver and encephalon. There were enhanced lobular pattern of the liver and yellowish areas in the cut surface of the encephalon, especially visualized in the cerebellar white matter. Microscopically, there was hepatocellular swelling and coagulative hepatic necrosis predominantly centrilobular with hemorrhages. Generalized perivascular edema and Alzheimer type II astrocytes were observed in the encephalon. The Alzheimer type II astrocytes showed weak or absent anti-glial fibrillar acid protein IS associated with positive IS for S-100 protein. The minimal lethal dose of Trema micrantha leaves was established at 20g/kg. The sensibility of horses to this plant, its wide distribution and high palatability reinforces the importance of Trema micrantha in accidental poisoning of horses.

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