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1.
Zootaxa ; 5404(1): 76-101, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38480406

RESUMO

Three new species of Tetrapedia Klug, 1810 (Apidae) from Central Brazil are described and illustrated: Tetrapedia marina sp. nov., Tetrapedia tereza sp. nov., and Tetrapedia bruno sp. nov. Additionally, a key to the 22 species of Tetrapedia known from Brazil is provided. The lectotype of T. clypeata Friese is designated to establish the species name.


Assuntos
Himenópteros , Abelhas , Animais , Brasil , Distribuição Animal
2.
Front Chem ; 11: 1267634, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795387

RESUMO

Introduction: The green revolution model that is followed in the Brazilian Cerrado is dependent on mechanization, chemical fertilization for soil dressing and correction, and the use of herbicides. Paraquat is a methyl viologen herbicide marketed as bipyridylium dichloride salts and used (in low doses) to combat weeds in their post-emergence stage. It is a non-selective pesticide that causes the peroxidation of the lipids that make up the cell membrane, and when it comes into contact with foliage, it results in the death of the plant. Methods: The effect of water molecules co-crystallized in Paraquat salt structures was analyzed in anhydrous, dihydrate, and trihydrate forms to understand those physicochemical properties in its redox activity. The frontier molecular orbitals were also carried out using DFT to obtain the chemical reactivity of the bipyridylium cation. Finally, the supramolecular arrangements were evaluated to analyze the physicochemical stability and acquire insights on superoxide anions. Results and discussion: The electronic structure indicated that the BP cation presents an acidic character due to its low ELUMO value, while the salt has a more basic character due to its high EHOMO value. For this reason, the BP ion is more susceptible to reduction during the weeds' photosynthesis process. During the process of plant photosynthesis, PQ is reduced to form a stable radical cation. In the supramolecular arrangement, the presence of water molecules increases the number of strong H-bonds, while the weak/moderate H-bonds are stabilized. PQ's toxic effects are observed in wildlife, domesticated animals, human populations, and ecosystems. The influence of PQ on the terrestrial environment is limited because of the soil adsorption capacity associated with good agricultural practices. The current use of good agricultural practices in the Cerrado seems not to prevent the environmental impacts of herbicides like PQ because it aims for the expansion and profitability of large-scale farming based on input-intensive practices instead of sustainable agriculture processes.

3.
Trop Med Infect Dis ; 8(9)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37755891

RESUMO

Leishmaniasis is a disease caused by protozoa of the genus Leishmania. Treatment options are limited, and there are frequent cases of treatment failure and clinical relapse. To understand these phenomena better, a systematic review was conducted, considering studies published between 1990 and 2021 in Portuguese, English, and Spanish. The review included 64 articles divided into three categories. Case reports (26 articles) focused on treatment failure and clinical relapse in cutaneous leishmaniasis patients (47.6%), primarily affecting males (74%) and children (67%), regardless of the clinical manifestation. Experimental studies on the parasite (19 articles), particularly with L. major (25%), indicated that alterations in DNA and genic expression (44.82%) played a significant role in treatment failure and clinical relapse. Population data on the human host (19 articles) identified immunological characteristics as the most associated factor (36%) with treatment failure and clinical relapse. Each clinical manifestation of the disease presented specificities in these phenomena, suggesting a multifactorial nature. Additionally, the parasites were found to adapt to the drugs used in treatment. In summary, the systematic review revealed that treatment failure and clinical relapse in leishmaniasis are complex processes influenced by various factors, including host immunology and parasite adaptation.

4.
Sci Rep ; 13(1): 14474, 2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660141

RESUMO

Stingless bees are major flower visitors in the tropics, but their foraging preferences and behavior are still poorly understood. Studying stingless bee interactions with angiosperms is methodologically challenging due to the high tropical plant diversity and inaccessibility of upper canopy flowers in forested habitats. Pollen DNA metabarcoding offers an opportunity of assessing floral visitation efficiently and was applied here to understand stingless bee floral resources spectra and foraging behavior. We analyzed pollen and honey from nests of three distantly related stingless bee species, with different body size and social behavior: Melipona rufiventris, Scaptotrigona postica and Tetragonisca angustula. Simultaneously, we evaluate the local floristic components through seventeen rapid botanical surveys conducted at different distances from the nests. We discovered a broad set of explored floral sources, with 46.3 plant species per bee species in honey samples and 53.67 in pollen samples. Plant families Myrtaceae, Asteraceae, Euphorbiaceae, Melastomataceae and Malpighiaceae dominated the records, indicating stingless bee preferences for abundant resources that flowers of these families provide in the region. Results also reinforce the preference of stingless bees for forest trees, even if only available at long distances. Our high-resolution results encourage future bee-plant studies using pollen and honey metabarcoding in hyper-diverse tropical environments.


Assuntos
Asteraceae , Mel , Abelhas , Animais , Pólen , Comportamento Social , Tamanho Corporal
5.
Int J Biol Macromol ; 253(Pt 5): 127085, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37774819

RESUMO

This study aimed to investigate the application of biopolymeric materials (chitosan, gelatin, and pomegranate peel extract as photosensitizer) and antimicrobial photodynamic therapy (aPDT) on the physicochemical and microbial safety of strawberries. The photosensitizer potential of the materials was confirmed by a light-dose-dependent photobleaching profile. The application of light (525 nm; 50 J cm-2) decreased by >2 log CFU mL-1 the survival of Staphylococcus aureus on the surface of the photoactive-biopolymeric films. Moreover, the materials did not present in vivo cytotoxicity using Danio rerio (Zebrafish) as well as cytophytotoxic, genotoxic, or mutagenic potentials against Allium cepa plant model, which points out their safety to be used as films without posing a risk to the humans and the environment. The photoactive-polymeric coatings were able to maintain the strawberries weight, and the association with green light was 100 % effective in delaying fungal contamination. These coated-strawberries presented a significant reduction in S. aureus survival after light application (5.47-4.34 log CFU mL-1). The molecular level analysis of the photoactive compound cyanidin-3-glucoside indicates absorption on UV-Vis consistent with aPDT action. Therefore, this study showed that the antimicrobial effects of aPDT combined with photoactive-biopolymeric coatings were enhanced, while the quality of the strawberries was maintained.


Assuntos
Anti-Infecciosos , Quitosana , Fragaria , Punica granatum , Humanos , Animais , Quitosana/farmacologia , Quitosana/química , Punica granatum/química , Fragaria/microbiologia , Fármacos Fotossensibilizantes , Gelatina , Staphylococcus aureus , Peixe-Zebra , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química
6.
J Mol Model ; 29(8): 241, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37436478

RESUMO

CONTEXT: The design and synthesis of safe and highly active sulfonylurea herbicides is still a challenge. Therefore, following some principles of structure-activity relationship (SAR) of sulfonylurea herbicides, this work focuses on evaluating two sulfonylurea derivatives bearing electron-withdrawing substituents, namely, -(CO)OCH3 and -NO2 on the aryl group, on herbicidal activity. To understand the effects caused by the substituent groups, the molecular and electronic structures of the sulfonylureas were evaluated by density functional theory. Likewise, the crystalline supramolecular arrangements of both compounds were analyzed by Hirshfeld surface, QTAIM, and NBO, with the aim of verifying changes in intermolecular interactions caused by substituent groups. Finally, through a toxicophoric analysis, we were able to predict the interacting groups in their biological target, acetolactate synthase, and verify the interactions with the binding site. METHODS: All theoretical calculations were conducted using the highly parameterized empirical exchange-correlation functional M06-2X accompanied by the diffuse and polarized basis set 6-311++G(d,p). The atomic coordinates were obtained directly from the crystalline structures, and from the energies of the frontier molecular orbitals (HOMO and LUMO), chemical descriptors were obtained that indicated the influence of the functional groups in the sulfonylureas on the reactivity of the molecules. The intermolecular interactions in the crystals were analyzed using the Hirshfeld, QTAIM, and NBO surfaces. Toxicophoric modeling was performed by the PharmaGist webserver and molecular docking calculations were performed by the GOLD 2022.1.0 software package so that the ligand was fitted to the binding site in a 10 Å sphere. For this, genetic algorithm parameters were used using the ChemPLP scoring function for docking and ASP for redocking.


Assuntos
Acetolactato Sintase , Herbicidas , Simulação de Acoplamento Molecular , Modelos Moleculares , Acetolactato Sintase/química , Acetolactato Sintase/metabolismo , Herbicidas/química , Herbicidas/farmacologia , Compostos de Sulfonilureia/química , Compostos de Sulfonilureia/farmacologia , Pirimidinas
7.
Rev Enferm UFPI ; 11(1): e2863, 2022-12-31. tab
Artigo em Inglês, Português | LILACS, BDENF - Enfermagem | ID: biblio-1519600

RESUMO

Objetivo: Avaliar os indicadores antropométricos e o consumo alimentar de pessoas com diabetes mellitus tipo 2 atendidas em uma unidade básica de saúde na cidade de São Luís, Maranhão.Métodos:Trata-se de um estudo do tipo transversal, descritivo, com abordagem quantitativa realizado com 46 pacientes portadores de diabetes mellitus tipo 2,atendidos em uma unidade básica de saúde da capital maranhense. Foram utilizados formulários semiestruturados para a coleta de dados sociodemográficos, antropométricos e relacionados aos hábitos alimentares. As análises foram realizadas por meio de estatística descritiva, com dados sendo representados através de média, frequência e seus respectivos desvios padrões além do teste de correlação de Pearson entre as variáveis quantitativas. Resultados:A amostra foi representada em maioria por mulheres(54,4%), idosos (59,6%), sedentários (63,1%), que apresentavam alta obesidade abdominal (80,4%),ingeriam baixa quantidade de fibras (93,5%) e consumiam em grande quantidade proteínas (67,4%), gorduras saturadas (69,6%) esacarose (57,5%).Conclusão: Fatores como peso inadequado e alimentação desregulada podem representar risco para o controle glicêmico e contribuir para o agravamento do diabetes mellitus. Descritores: Diabetes mellitus. Estado nutricional. Ingestão de alimentos.


Objective: To evaluate the anthropometric indicators and food consumption of people with Type2 Diabetes Mellitustreated at a Basic Health Unit in the city of São Luís, Maranhão. Methods: This is a cross-sectional and descriptive study with a quantitative approach conducted with 36patients who have Type2 Diabetes Mellitus, treated at a BasicHealth Unit in the capital city of Maranhão. Semi-structured forms were used to collect sociodemographic and anthropometric data, as well as related to eating habits. The analyses were performed using descriptive statistics, with data represented as mean,frequency and their respective standard deviations, in addition to Pearson's correlation test between the quantitative variables. Results: The sample was mostly representedby women (54.4%), older adults(59.6%), sedentary people (63.1%), who had high abdominal obesity (80.4%), ingested a low amount of fiber (93.5%) and consumed a large amount ofprotein (67.4%), saturated fat(69.6%) and sucrose (57.5%). Conclusion: Factors such as inadequate weight and unregulated eating habits can represent risks for glycemic control and contribute to worsening of Diabetes Mellitus. Descriptors:Diabetes mellitus. Nutritional status. Eating.


Assuntos
Estado Nutricional , Diabetes Mellitus , Ingestão de Alimentos
8.
Molecules ; 27(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36432059

RESUMO

Angiotensin-converting enzyme (ACE) inhibitors are one of the most active classes for cardiovascular diseases and hypertension treatment. In this regard, developing active and non-toxic ACE inhibitors is still a continuous challenge. Furthermore, the literature survey shows that oxidative stress plays a significant role in the development of hypertension. Herein, glutathione's molecular structure and supramolecular arrangements are evaluated as a potential ACE inhibitor. The tripeptide molecular modeling by density functional theory, the electronic structure by the frontier molecular orbitals, and the molecular electrostatic potential map to understand the biochemical processes inside the cell were analyzed. The supramolecular arrangements were studied by Hirshfeld surfaces, quantum theory of atoms in molecules, and natural bond orbital analyses. They showed distinct patterns of intermolecular interactions in each polymorph, as well as distinct stabilizations of these. Additionally, the molecular docking study presented the interactions between the active site residues of the ACE and glutathione via seven hydrogen bonds. The pharmacophore design indicated that the hydrogen bond acceptors are necessary for the interaction of this ligand with the binding site. The results provide useful information for the development of GSH analogs with higher ACE inhibitor activity.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Hipertensão , Humanos , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/química , Simulação de Acoplamento Molecular , Sítios de Ligação , Glutationa
9.
J Mol Model ; 28(10): 338, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36181566

RESUMO

Active pharmaceutical ingredients are formulated as the salt form, aiming to modulate their physicochemical properties. In this regard, the optimization and choice of the salt former have a strong influence on toxicity, therapeutic efficiency, and bioavailability. Sulfamethoxazole (SMZ) salts with Na+, Cl-, and Br- counterions influence in the supramolecular arrangement as well as in their thermodynamic and kinetic parameters. Herein, we analyzed the interactions of the Na+, Cl-, and Br- counterions on the supramolecular arrangement of the sulfamethoxazole salts by Hirshfeld surfaces, fingerprint plots, and theoretical methods-quantum theory of atoms in molecules and natural bond orbitals. Moreover, we evaluated their electronic structure by density functional theory using calculation of the frontier molecular orbitals. Molecular electrostatic potential maps were also obtained to predict the interactions of the counterions along crystalline arrangements. We observed that the structures of [SMZ]+ and [SMZ]- ions differ slightly from the SMZ. The chemical reactivity indices show that the SMZ is kinetically more stable than its respective ions, while its anion is more polarizable, and its cation has a higher global electrophilicity index. The molecular electrostatic potential maps show high charge density in the sulfonyl group (nucleophilic region) and the heterocyclic amino group (electrophilic region). Although the molecular skeleton is identical among the three SMZ species and the presence of different counterions in the formation of the crystalline structure of the salts results in supramolecular arrangements with different patterns of intermolecular interactions, despite being very similar in terms of intensities.


Assuntos
Sais , Sulfametoxazol , Íons/química , Preparações Farmacêuticas , Eletricidade Estática
10.
J Phys Chem A ; 126(43): 7852-7863, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36282217

RESUMO

The structural and electronic properties of 2,3-dimethoxybenzaldehyde (2,3-DMB), 5-bromo-2,3-dimethoxybenzaldehyde (5-BRB), and 6-bromo-2,3-dimethoxybenzaldehyde (6-BRB) were extensively discussed with emphasis on linear and nonlinear optical responses. The intermolecular interactions were comparatively studied by Hirshfeld surfaces, quantum theory of atoms in molecules (QTAIM), and natural bond orbitals (NBOs), indicating that bromine substitution decreases the H···H and C···H contacts and increases H···Br and Br···Br closed-shell interactions on crystalline arrangements. The frontier molecular orbitals and molecular electrostatic potential map, carried out at the CAM-B3LYP/6-311++G(d,p) level of theory, showed that the kinetic stability occurs in the increasing order 6-BRB < 5-BRB < 2.3-DMB. The bromine atom has a beneficial effect on the nonlinear third-order susceptibility of 2,3-DMB, with theoretical predictions of 89.54 ×10-22 and 83.15 ×10-22 (m/V)2 for 6-BRB and 5-BRB, respectively. These findings were favorably compared with available theoretical and experimental data of other organic crystals that may be promising as NLO materials.

11.
Am J Bot ; 108(5): 828-843, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34019302

RESUMO

PREMISE: There is little direct evidence linking floral development and pollination biology in plants. We characterize both aspects in plain and ornamented flowers of Trimezieae (Iridaceae) to investigate how changes in floral ontogeny may affect their interactions with pollinators through time. METHODS: We examined floral ontogeny in 11 species and documented pollination biology in five species displaying a wide range of floral morphologies. We coded and reconstructed ancestral states of flower types over the tribal phylogeny to estimate the frequency of transition between different floral types. RESULTS: All Trimezieae flowers are similar in early floral development, but ornamented flowers have additional ontogenetic steps compared with plain flowers, indicating heterochrony. Ornamented flowers have a hinge pollination mechanism (newly described here) and attract more pollinator guilds, while plain flowers offer less variety of resources for a shorter time. Although the ornamented condition is plesiomorphic in this clade, shifts to plain flowers have occurred frequently and abruptly during the past 5 million years, with some subsequent reversals. CONCLUSIONS: Heterochrony has resulted in labile morphological changes during flower evolution in Trimezieae. Counterintuitively, species with plain flowers, which are endemic to the campo rupestre, are derived within the tribe and show a higher specialization than the ornamented species, with the former being visited by pollen-collecting bees only.


Assuntos
Iridaceae , Polinização , Animais , Abelhas , Biologia , Flores , Pólen
12.
J Mol Model ; 27(2): 65, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33532877

RESUMO

This work describes a comparative molecular structure of two hydroxychlorochalcones with an emphasis on their planarity. Hirshfeld surface analysis investigates the effect of ortho- and para-chlorine substitution on supramolecular arrangement and physical chemical properties. The molecular conformation of 2'-hydroxy-4',6'-dimethyl-2-chlorochalcone and 2'-hydroxy-4',6'-dimethyl-4-chlorochalcone chalcones was obtained through DFT with the exchange-correlation functional M06-2X and the 6-311++G(2d,2p) basis set, and the results were compared with the experimental X-ray data in order to get insights on the effect of ortho- and para-chlorine substitution. The charge transfer into entire main carbon chain was also investigated using frontier molecular orbitals (HOMO and LUMO), NBO, and MEP map in order to describe the comparative conformational stability due to the resonance effect produced by π electron displacements. Finally, the intermolecular observed interactions were analyzed by QTAIM, with the M06-2X/6-311G++(d,p) theory level.

13.
J Equine Vet Sci ; 92: 103146, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32797776

RESUMO

The goal of this study was to compare the efficiency of histrelin acetate (GnRH analog) and human chorionic gonadotropin (hCG) to hasten ovulation in Brazilian Northeastern jennies (Equus africanus asinus). Thirty cycles of ten jennies were randomly assigned in one of the three groups: G0 (control group), saline; G1, 250 µg of histrelin acetate; G2, 2500 IU of hCG. Jennies were evaluated by transrectal palpation and ultrasonography, and had the administration of an ovulation-inducing agent when a follicle measuring between 29 and 32 mm of diameter was diagnosed. Jennies were monitored every 6 hours by transrectal ultrasonography until ovulation. The interval between prostaglandin administration and ovulation was lower (P < .05) in jennies from the G1 (145.2 ± 34.6 hours) and G2 (147.4 ± 27.3 hours) groups compared with the control cycle (220.0 ± 41.8 hours). Both treatments (G1, 41.15 ± 3.5 hours; G2, 37.8 ± 2.5 hours) also reduced (P < .05) the interval that jennies took to ovulate after the administration of the ovulation-inducing agent compared with the control (81.8 ± 28.8 hours). All jennies from G1 and G2 ovulated up to 48 hours after ovulation induction, whereas 100% of jennies in the control cycle ovulated later (>48 hours from the administration of saline). In conclusion, both histrelin acetate and hCG at the used dose are efficient ovulation-inducing agents in jennies promoting ovulation up to 48 hours after administration.


Assuntos
Equidae , Ovulação , Acetatos , Animais , Brasil , Gonadotropina Coriônica , Feminino , Hormônio Liberador de Gonadotropina/análogos & derivados
14.
J Mol Model ; 26(9): 243, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32816129

RESUMO

This work presents the synthesis of the chalcone (E)-3-(2,6-difluorophenyl)-1-(furan-2-yl)-prop-2-en-1-one molecule through the equimolar reaction between 1-(furan-2-yl)-ethenone and 2,6-difluorobenzaldehyde. The crystallographic characterization and the extensive theoretical study regarding electronic properties were obtained. The supramolecular arrangement was described by X-ray diffraction and Hirshfeld surfaces. Optimized geometrical structure was obtained by density functional theory, and the electronic study for differences between the solid and gas phases was carried out with M062-X at 6-311++G(2d,2p) basis set. Natural bond orbital, frontier molecular orbitals (HOMO-LUMO), and molecular electrostatic potential map were determined to elucidate the information related to the charge transfer in the molecule. The theoretical and experimental vibrational spectra were plotted, which included the IR intensities, the calculated and experimental vibrational frequencies, and the assigned vibrational modes for the main groups of DTP.

15.
Mol Phylogenet Evol ; 143: 106692, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31770589

RESUMO

Worldwide distributed tropical savannas were established only in the Miocene, with climatic cooling and rise of C4 grasses. However, there is evidence for an earlier presence of savanna-like vegetation in southern parts of South America. Here we investigated the biogeographic history of a clade of solitary bees which have endemic groups in areas covered by savannas and other types of open vegetation as well as forested areas. We hypothesized that these bees originated in savanna-like biomes and that shifts to forested areas and floral host shifts increased species diversification along their evolutionary history. We reconstructed a comprehensive phylogeny for Tapinotaspidini bees based majorly on original DNA sequences. We then used macroevolutionary tools to estimate ancestral range area and reconstructed ancestral habitat (open versus forested) and host plant association to analyze the effects of shifts in vegetation type and flower hosts on their diversification. Tapinotaspidini bees originated in the Paleocene and in a savanna-type, Cerrado-like, which is reinforced by reconstruction of open vegetation as the most probable ancestral area, thus bringing additional evidence to a much earlier origin of this vegetation type in South America. Shifts to forested areas occurred at least three times in a period of 30 Ma and were responsible for slight increases in diversification rates. Malpighiaceae is the ancestral floral host; host broadening occurred only in the Miocene and at least in three occasions. Host shifts, i.e. from Malpighiaceae to other oil families, occurred in the Eocene and Miocene. Both host broadening and host shifts did not significantly alter diversification rates, however exploitation of other oil sources were important in occupying new habitats. The link between biomes and host plant shifts and changes in diversification rate brings us additional insights into the evolution of bees and associated flora in South America.


Assuntos
Abelhas/classificação , Animais , Abelhas/genética , Abelhas/fisiologia , Evolução Biológica , Complexo IV da Cadeia de Transporte de Elétrons/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fósseis/história , Pradaria , História Antiga , Malpighiaceae/crescimento & desenvolvimento , Malpighiaceae/fisiologia , Filogenia , Filogeografia , América do Sul
16.
Pap. avulsos Zool. ; 59: e.20195936, Oct. 3, 2019. ilus
Artigo em Inglês | VETINDEX | ID: vti-24643

RESUMO

Here we provide descriptions of gynandromorphs of two species oil-collecting bees: Lophopedia nigrispinis and Epicharis iheringii, both with partial bilateral phenotypic asymmetry. The bees have a female phenotype predominantly on mesosoma and metasoma. The specimen of L. nigrispinis has distinct characteristics on legs, suggesting a mosaic pattern of gynandromorphism. The pollen and oil loads on legs suggest that the bee was foraging normally. The gynander specimen of E. iheringii has mostly a female phenotype, except for head, with right half female type and left half male type. The specimen of L. nigrispinis was collected foraging on flowers of Bidens sp. at Parque Nacional Iguazú, Argentina with loads of pollen on legs suggesting it was reproductive and was provisioning a nest. The specimen of Epicharis iheriingi has no evidence of any oil or pollen collection, despite its mostly female phenotype.(AU)


Assuntos
Animais , Abelhas/anatomia & histologia , Caracteres Sexuais , Transtornos do Desenvolvimento Sexual , Polinização/genética , Pólen
17.
Reprod Domest Anim ; 54(12): 1567-1573, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31520567

RESUMO

This study aims to investigate the effect of melatonin on activation, growth and morphology of bovine primordial follicles, as well as on stromal cells density in ovarian tissues after in vitro culture. Ovarian fragments were cultured in α-MEM+ alone or supplemented with melatonin (250, 500, 1,000 or 2,000 pM) for a period of six days. Non-cultured and cultured tissues were processed for histological analysis; according to developmental stages, follicles were classified as primordial or growing follicles. These follicles were further classified as morphologically normal or degenerated. Ovarian stromal cell density was also evaluated. The percentages of primordial and developing follicles, as well as those classified of normal follicles, were compared by Fisher's exact test, and the differences were considered significant when p < .05. The results showed that the presence of 1,000 and 2,000 pM melatonin in culture medium promoted a reduction in the percentage of primordial follicles and an increase in the percentage of development follicles, when compared to follicles cultured in control medium. On the other hand, the presence of 250 or 500 pM melatonin did not show a significant effect on the percentage of primordial and developing follicles. Besides that, the presence of 500, 1,000 and 2,000 pM melatonin maintained the percentage of normal follicles similar to those seen uncultured control. Moreover, tissues cultured in presence of 1,000 pM melatonin showed a higher percentage of normal follicles when compared to follicles cultured in the presence of 250 pM melatonin. It was observed a similar profile of stromal density in both uncultured tissues and those cultured in vitro in the presence of melatonin. In conclusion, melatonin (1,000 and 2,000 pM) promotes bovine primordial follicles activation and maintains the stromal cell density during in vitro culture of ovarian cortical tissue.


Assuntos
Antioxidantes/farmacologia , Melatonina/farmacologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos/veterinária , Animais , Bovinos , Feminino
18.
Pap. avulsos zool ; 59: e.20195936, 25 mar. 2019. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1487210

RESUMO

Here we provide descriptions of gynandromorphs of two species oil-collecting bees: Lophopedia nigrispinis and Epicharis iheringii, both with partial bilateral phenotypic asymmetry. The bees have a female phenotype predominantly on mesosoma and metasoma. The specimen of L. nigrispinis has distinct characteristics on legs, suggesting a mosaic pattern of gynandromorphism. The pollen and oil loads on legs suggest that the bee was foraging normally. The gynander specimen of E. iheringii has mostly a female phenotype, except for head, with right half female type and left half male type. The specimen of L. nigrispinis was collected foraging on flowers of Bidens sp. at Parque Nacional Iguazú, Argentina with loads of pollen on legs suggesting it was reproductive and was provisioning a nest. The specimen of Epicharis iheriingi has no evidence of any oil or pollen collection, despite its mostly female phenotype.


Assuntos
Animais , Abelhas/anatomia & histologia , Caracteres Sexuais , Polinização/genética , Transtornos do Desenvolvimento Sexual , Pólen
19.
Vet Rec ; 181(15): 402, 2017 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-28822974

RESUMO

Dexmedetomidine (DEX) alone, or combined with butorphanol (BUT), may be administered by constant rate infusions (CRIs) in standing horses. This blinded, randomised, crossover study in six healthy adult horses aimed to determine the sedative and cardiopulmonary effects of DEX (dexmedetomidine (3.5 µg/kg+5 µg/kg/hour CRI) and DEX/BUT (dexmedetomidine (3.5 µg/kg+3.5 µg/kg/hour CRI) and butorphanol (20 µg/kg+24 µg/kg/hour CRI)). Head height above ground (HHAG), ataxia, responses to tactile/auditory stimuli and cardiopulmonary variables were recorded before, at 5/15/30/60/90 minutes and after CRIs terminated (15/30/60 minutes). Repeated measures analysis of variance with Tukey-Kramer test were used for cardiopulmonary values (mean±SD) and HHAG reduction (per cent), and Friedman's and Dunn's for non-parametric data (P<0.05). Maximum HHAG reductions of 54 per cent (DEX) and 58 per cent (DEX/BUT) occurred at 15 minutes, with ataxia for 15 minutes in both treatments. Responses to stimuli were reduced for 30 minutes in both treatments, and auditory up to 60 minutes in DEX. Cardiopulmonary effects typical of α2-agonists were observed, with no differences between treatments. At the doses and rates reported here, both regimens provided clinically sufficient sedation for only 30 minutes.


Assuntos
Analgésicos Opioides/farmacologia , Anestésicos Combinados/farmacologia , Butorfanol/farmacologia , Sistema Cardiovascular/efeitos dos fármacos , Dexmedetomidina/farmacologia , Hipnóticos e Sedativos/farmacologia , Sistema Respiratório/efeitos dos fármacos , Analgésicos Opioides/administração & dosagem , Anestésicos Combinados/administração & dosagem , Animais , Butorfanol/administração & dosagem , Estudos Cross-Over , Dexmedetomidina/administração & dosagem , Feminino , Cavalos , Hipnóticos e Sedativos/administração & dosagem , Infusões Intravenosas/métodos , Infusões Intravenosas/veterinária , Masculino , Postura , Método Simples-Cego
20.
PLoS One ; 9(6): e99903, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24932729

RESUMO

Planting of native trees for habitat restoration is a widespread practice, but the consequences for the retention and transmission of genetic diversity in planted and natural populations are unclear. Using Inga vera subsp. affinis as a model species, we genotyped five natural and five planted populations in the Atlantic forest of northeastern Brazil at polymorphic microsatellite loci. We studied the breeding system and population structure to test how much genetic diversity is retained in planted relative to natural populations. We then genotyped seedlings from these populations to test whether genetic diversity in planted populations is restored by outcrossing to natural populations of I. vera. The breeding system of natural I. vera populations was confirmed to be highly outcrossing (t = 0.92; FIS = -0.061, P = 0.04), with populations showing weak population substructure (FST = 0.028). Genetic diversity in planted populations was 50% less than that of natural populations (planted: AR = 14.9, HO = 0.865 and natural: AR = 30.8, HO = 0.655). However, seedlings from planted populations showed a 30% higher allelic richness relative to their parents (seedlings AR = 10.5, parents AR = 7.6). Understanding the processes and interactions that shape this system are necessary to provide ecologically sensible goals and successfully restore hyper-fragmented habitats. Future restoration plans for I. vera must consider the genetic diversity of planted populations and the potential for gene flow between natural populations in the landscape, in order to preserve ecological interactions (i.e. pollination), and promote opportunities for outcrossing.


Assuntos
Ecossistema , Fabaceae/genética , Fabaceae/fisiologia , Árvores/genética , Árvores/fisiologia , Clima Tropical , Cruzamento , Variação Genética , Genética Populacional , Geografia , Repetições de Microssatélites/genética , Plântula/genética
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