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1.
An Acad Bras Cienc ; 94(4): e20201775, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36228212

RESUMO

We evaluated the influence of the substitution of soybean meal by detoxified castor cake on performance, digestibility of nutrients, nitrogen balance, hepatic and renal functions of pregnant goats fed with diets containing detoxified castor cake by alkaline solutions during the stages (first two-thirds and final third) of pregnancy. Three diets were provided: one based on soybean meal and the other two based on castor cake detoxified with whit calcium hydroxide or sodium hydroxide. Goats fed detoxified castor cake sodium hydroxide had lower consumption. Was no effect (P>0.05) of diets or stages on the digestibility of dry matter and nutrients. The goats that received the diets based on soybean meal and detoxified castor cake calcium hydroxide consumed larger amounts of nitrogen. The goats fed with diet the basis of SM had greater weight in the parturition day. The average levels of enzymes for hepatic and renal functions were within normal patterns. Of enzymes related to liver metabolism, only the gamma-glutamyl transferase increased in the final third of pregnancy. The present study demonstrated that detoxified castor by sodium hydroxide reduces the consumption of goats during gestation, but did not affect negatively the renal and hepatic parameters.


Assuntos
Ração Animal , Cabras , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Hidróxido de Cálcio , Óleo de Rícino , Dieta/veterinária , Digestão , Feminino , Rim/fisiologia , Fígado , Nitrogênio , Gravidez , Hidróxido de Sódio , Transferases
2.
Molecules ; 26(18)2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34577145

RESUMO

Chagas disease (CD) affects more than 6 million people worldwide. The available treatment is far from ideal, creating a demand for new alternative therapies. Botanical diversity provides a wide range of novel potential therapeutic scaffolds. Presently, our aim was to evaluate the mammalian host toxicity and anti-Trypanosoma cruzi activity of botanic natural products including extracts, fractions and purified compounds obtained from Brazilian flora. In this study, 36 samples of extracts and fractions and eight pure compounds obtained from seven plant species were evaluated. The fraction dichloromethane from Aureliana fasciculata var. fasciculata (AFfPD) and the crude extract of Piper tectoniifolium (PTFrE) showed promising trypanosomicidal activity. AFfPD and PTFrE presented EC50 values 10.7 ± 2.8 µg/mL and 12.85 ± 1.52 µg/mL against intracellular forms (Tulahuen strain), respectively. Additionally, both were active upon bloodstream trypomastigotes (Y strain), exhibiting EC50 2.2 ± 1.0 µg/mL and 38.8 ± 2.1 µg/mL for AFfPD and PTFrE, respectively. Importantly, AFfPD is about five-fold more potent than Benznidazole (Bz), the reference drug for CD, also reaching lower EC90 value (7.92 ± 2.2 µg/mL) as compared to Bz (23.3 ± 0.6 µg/mL). Besides, anti-parasitic effect of eight purified botanic substances was also investigated. Aurelianolide A and B (compounds 1 and 2) from A. fasciculata and compound 8 from P. tuberculatum displayed the best trypanosomicidal effect. Compounds 1, 2 and 8 showed EC50 of 4.6 ± 1.3 µM, 1.6 ± 0.4 µM and 8.1 ± 0.9 µM, respectively against intracellular forms. In addition, in silico analysis of these three biomolecules was performed to predict parameters of absorption, distribution, metabolism and excretion. The studied compounds presented similar ADMET profile as Bz, without presenting mutagenicity and hepatotoxicity aspects as predicted for Bz. Our findings indicate that these natural products have promising anti-T. cruzi effect and may represent new scaffolds for future lead optimization.


Assuntos
Biodiversidade , Produtos Biológicos , Trypanosoma cruzi , Brasil , Simulação por Computador
3.
Implant Dent ; 22(2): 193-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23442599

RESUMO

INTRODUCTION: Passive fit has been considered an important requirement for the longevity of implant-supported prostheses. Among the different steps of prostheses construction, casting is a feature that can influence the precision of fit and consequently the uniformity of possible deformation among abutments upon the framework connection. PURPOSE: This study aimed at evaluating the deformation of abutments after the connection of frameworks either cast in one piece or after soldering. MATERIALS AND METHODS: A master model was used to simulate a human mandible with 5 implants. Ten frameworks were fabricated on cast models and divided into 2 groups. Strain gauges were attached to the mesial and distal sides of the abutments to capture their deformation after the framework's screw retentions were tightened to the abutments. RESULTS: The mean values of deformation were submitted to a 3-way analysis of variance that revealed significant differences between procedures and the abutment side. The results showed that none of the frameworks presented a complete passive fit. CONCLUSION: The soldering procedure led to a better although uneven distribution of compression strains on the abutments.


Assuntos
Dente Suporte , Ligas Dentárias/química , Projeto do Implante Dentário-Pivô , Implantes Dentários , Soldagem em Odontologia/métodos , Técnica de Fundição Odontológica , Adaptação Marginal Dentária , Prótese Dentária Fixada por Implante , Humanos , Teste de Materiais , Fenômenos Mecânicos , Paládio/química , Prata/química , Propriedades de Superfície , Torque
4.
Curr Med Chem ; 19(14): 2176-228, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22414104

RESUMO

Infections with protozoan parasites are a major cause of disease and mortality in many tropical countries of the world. Diseases caused by species of the genera Trypanosoma (Human African Trypanosomiasis and Chagas Disease) and Leishmania (various forms of Leishmaniasis) are among the seventeen "Neglected Tropical Diseases" (NTDs) defined by the WHO. Furthermore, malaria (caused by various Plasmodium species) can be considered a neglected disease in certain countries and with regard to availability and affordability of the antimalarials. Living organisms, especially plants, provide an innumerable number of molecules with potential for the treatment of many serious diseases. The current review attempts to give an overview on the potential of such plant-derived natural products as antiprotozoal leads and/or drugs in the fight against NTDs. In part I, a general description of the diseases, the current state of therapy and need for new therapeuticals, assay methods and strategies applied in the search for new plant derived natural products against these diseases and an overview on natural products of terpenoid origin with antiprotozoal potential were given. The present part II compiles the current knowledge on natural products with antiprotozoal activity that are derived from the shikimate pathway (lignans, coumarins, caffeic acid derivatives), quinones of various structural classes, compounds formed via the polyketide pathways (flavonoids and related compounds, chromenes and related benzopyrans and benzofurans, xanthones, acetogenins from Annonaceae and polyacetylenes) as well as the diverse classes of alkaloids. In total, both parts compile the literature on almost 900 different plant-derived natural products and their activity data, taken from over 800 references. These data, as the result of enormous efforts of numerous research groups world-wide, illustrate that plant secondary metabolites represent an immensely rich source of chemical diversity with an extremely high potential to yield a wealth of lead structures towards new therapies for NTDs. Only a small percentage, however, of the roughly 200,000 plant species on earth have been studied chemically and only a small percentage of these plants or their constituents has been investigated for antiprotozoal activity. The repository of plant-derived natural products hence deserves to be investigated even more intensely than it has been up to present.


Assuntos
Antiprotozoários/uso terapêutico , Produtos Biológicos/uso terapêutico , Doenças Negligenciadas/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Plantas Medicinais/química , Infecções por Protozoários/tratamento farmacológico , Animais , Antiprotozoários/química , Antiprotozoários/metabolismo , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Humanos , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Plantas Medicinais/metabolismo
5.
Curr Med Chem ; 19(14): 2128-75, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22414103

RESUMO

Infections with protozoan parasites are a major cause of disease and mortality in many tropical countries of the world. Diseases caused by species of the genera Trypanosoma (Human African Trypanosomiasis and Chagas Disease) and Leishmania (various forms of Leishmaniasis) are among the seventeen "Neglected Tropical Diseases" (NTDs) defined as such by WHO due to the neglect of financial investment into research and development of new drugs by a large part of pharmaceutical industry and neglect of public awareness in high income countries. Another major tropical protozoan disease is malaria (caused by various Plasmodium species), which -although not mentioned currently by the WHO as a neglected disease- still represents a major problem, especially to people living under poor circumstances in tropical countries. Malaria causes by far the highest number of deaths of all protozoan infections and is often (as in this review) included in the NTDs. The mentioned diseases threaten many millions of lives world-wide and they are mostly associated with poor socioeconomic and hygienic environment. Existing therapies suffer from various shortcomings, namely, a high degree of toxicity and unwanted effects, lack of availability and/or problematic application under the life conditions of affected populations. Development of new, safe and affordable drugs is therefore an urgent need. Nature has provided an innumerable number of drugs for the treatment of many serious diseases. Among the natural sources for new bioactive chemicals, plants are still predominant. Their secondary metabolism yields an immeasurable wealth of chemical structures which has been and will continue to be a source of new drugs, directly in their native form and after optimization by synthetic medicinal chemistry. The current review, published in two parts, attempts to give an overview on the potential of such plant-derived natural products as antiprotozoal leads and/or drugs in the fight against NTDs.


Assuntos
Antiprotozoários/uso terapêutico , Produtos Biológicos/uso terapêutico , Doenças Negligenciadas/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Infecções por Protozoários/tratamento farmacológico , Animais , Antiprotozoários/química , Antiprotozoários/metabolismo , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Humanos , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/metabolismo
9.
Folia Parasitol (Praha) ; 47(3): 216-26, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11104150

RESUMO

The development of the nematode Procamallanus saccobranchi Karve, 1952, a parasite in the stomach of the fish Heteropneustes fossilis (Bloch), was studied in Mesocyclops crassus (Fischer) and Mesocyclops leuckarti (Claus). After being ingested by the copepods the nematode first-stage larvae penetrated into the haemocoel of the intermediate host; there they moulted twice (on days 3 and 5 p.i. at 28-30 degrees C) attaining the third, infective stage. The definitive host H. fossilis acquired infection by feeding on copepods harbouring infective-stage larvae; in the stomach of this definitive host, the larvae were observed to undergo two more moults. The third moult occurred on day 13 p.i. and the fourth moult on day 38 p.i. and day 66 p.i. in "male" and "female" larvae, respectively. The larval stages, including the moulting forms are described and illustrated.


Assuntos
Peixes/parasitologia , Nematoides/crescimento & desenvolvimento , Animais , Clorpromazina , Crustáceos/parasitologia , Feminino , Água Doce , Índia , Muda , Nematoides/anatomia & histologia , Estômago/parasitologia
14.
Folia Parasitol (Praha) ; 42(3): 220-6, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8774775

RESUMO

A new nemarode, Dichelyne alatae sp. n., is described on the basis of the worms recovered from the intestine of the whiting, Sillaginopsis panijus (Perciformes: Sillaginidae) from the estuary of the river Hooghly at Kalyani, West Bengal, India. Dichelyne alatae differs from congeners in having a small body size, deirids posterior to the oesophagus, short and wide caudal alae at the level of cloacal opening, unequal, alate spicules, a shield-shaped gubernaculum, a different number of caudal papillae and a conical tail with spines in its distal region.


Assuntos
Nematoides/isolamento & purificação , Perciformes/parasitologia , Animais , Feminino , Índia , Intestinos/parasitologia , Masculino , Nematoides/anatomia & histologia , Nematoides/ultraestrutura
16.
Folia Parasitol (Praha) ; 40(1): 49-52, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8325564

RESUMO

The seasonal changes of the nematode Camallanus anabantis Pearse, 1933, in the climbing perch (Anabas testudineus) from the freshwater swamps near Kalyani town, West Bengal, India were studied during the period from February 1988 to August 1989. The nematode exhibited a one-year cycle. Larvated females occurred in the fishes from October to February at a water temperature of 12 degrees-29 degrees C. New infection of fishes occurred from February to May and occasionally in September. The fourth-stage larvae, the males, and the young females (without eggs), although irregularly, were found present throughout the year. Egg-laden females occurred in the fishes in August, October to February, and March.


Assuntos
Camallanina/crescimento & desenvolvimento , Doenças dos Peixes/epidemiologia , Percas/parasitologia , Infecções por Spirurida/veterinária , Animais , Camallanina/isolamento & purificação , Feminino , Doenças dos Peixes/parasitologia , Índia/epidemiologia , Masculino , Prevalência , Estações do Ano , Infecções por Spirurida/epidemiologia , Infecções por Spirurida/parasitologia
17.
Folia Parasitol (Praha) ; 39(2): 145-51, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1644361

RESUMO

The Raillietascaris varani (Baylis et Daubney, 1922), parasitic in the Indian monitor lizard, Varanus monitor (L.), was studied by scanning electron microscopy (SEM). A surface topography of the worm, especially the head and male tail, were described, illustrated and discussed with regard to the available data on this species, and also other species of ascaridoid nematodes. The present study confirms the previous observations from Sprent (1985), and also provides some additional information concerning the microtopography of the worm which might be useful in comparative studies on the Ascaridoidea.


Assuntos
Ascaridoidea/ultraestrutura , Lagartos/parasitologia , Animais , Feminino , Índia , Masculino , Microscopia Eletrônica de Varredura
18.
Folia Parasitol (Praha) ; 37(4): 295-9, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2093609

RESUMO

The nematode, Lappetascaris lutjani, recovered from the fish, Pellona ditchela from West Bengal, India, was studied by light and scanning electron microscopes. Surface features of the head and tail ends of the body as also the distal parts of the spicules were described, illustrated and discussed with regard to the available data relative to this species. Present LM studies provide information concerning the head structure in greater detail and existence of narrow but distinct lateral cervical alae. SEM studies give microtopographic details of the worm. Some of these represent new information and might be useful in the taxonomic evaluation of this interesting nematode. P. ditchela is the recorded new host of L. lutjani.


Assuntos
Peixes/parasitologia , Nematoides/anatomia & histologia , Animais , Feminino , Masculino , Nematoides/classificação
19.
Folia Parasitol (Praha) ; 35(1): 41-5, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3417200

RESUMO

Morphology of the nematode Spinitectus minor harboured by Mastacembelus armatus from Burdwan, West Bengal, India was studied by light and scanning electron microscopes. The worms were described, illustrated and discussed taking into consideration of the information available relative to this species. Alate spicules, polar caps on the eggs and prodelphic uteri are clearly seen in the present LM studies and SEM photomicrographs provided detailed information about the microtopography of the worms.


Assuntos
Nematoides/ultraestrutura , Animais , Feminino , Peixes/parasitologia , Masculino , Microscopia Eletrônica de Varredura
20.
Am J Hosp Pharm ; 43(6): 1486-8, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3728484

RESUMO

The stability of pentamidine isethionate in small-volume intravenous admixtures was studied. In an initial experiment, duplicate admixtures containing pentamidine 1 or 2 mg/mL were prepared using 100 mL each of 5% dextrose injection and 0.9% sodium chloride injection in polyvinyl chloride (PVC) bags. All solutions were kept at room temperature and were assayed at various times up to 48 hours by high-performance liquid chromatography. Solutions were also examined visually and tested for pH at each assay time. In a second experiment, single admixtures containing pentamidine 2 mg/mL were prepared in 100-mL PVC bags of both 5% dextrose injection and 0.9% sodium chloride injection. After time-zero determinations of pentamidine concentration, pH, and visual clarity, solutions were allowed to run through PVC infusion sets at 20 mL/hr. Samples were collected at the distal end of each set at various times up to five hours for analysis of pentamidine concentration, pH, and clarity. All admixtures in the initial experiment retained greater than 90% of initial concentration for the 48-hour study period. However, 5% dextrose admixtures infused through PVC administration sets showed a loss in initial concentration of about 2%, while 0.9% sodium chloride admixtures lost about 10% of initial concentration after infusion through these sets. The pH of all solutions in both experiments varied by less than 0.5 units, and no particulate matter or color change was noted in any of the admixtures. In the concentrations and diluents studied, pentamidine appears to be stable for 48 hours in PVC bags. Slight losses in the initial concentrations of these solutions after infusing them through PVC infusion sets may be caused by adsorption to the set.


Assuntos
Amidinas/análise , Pentamidina/análise , Embalagem de Medicamentos , Estabilidade de Medicamentos , Glucose , Infusões Parenterais , Injeções Intravenosas , Pentamidina/administração & dosagem , Cloreto de Polivinila , Cloreto de Sódio
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