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1.
Plant Biol (Stuttg) ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38837312

RESUMEN

Rocky outcrop environments at high altitudes have nutrient-poor soil, where species are exposed to water scarcity and high solar radiation. Baccharis platypoda DC. occurs in such an environment and has a rigid and transparent secretion that covers the entire inflorescence. We analysed and compared the secretory structures and their chemical composition in female and male inflorescences of B. platypoda, a dioecious species, to explore chemodiversity within this species and assess potential differences between individuals. Our investigation also aims to understand the occurrence of these substances in the genus Baccharis L. Chemical compounds and secretory structures were similar in female and male inflorescences. There are glandular trichomes on the epidermis of the abaxial surface of bracts, and secretory ducts in the axis of the inflorescence, as well as in sepals, petals, and bracts. Histochemical tests were positive for phenolic compounds, flavonoids, proteins, pectin, and lipids, but not for mucilage. Flavonoid content varied between 6.24% and 9.81%, being higher in female inflorescences. Chromatography revealed the presence of several phenolic compounds, some terpenes, and other less frequent classes in both female and male inflorescences. We highlight that trichomes found on these surfaces produce abundant phenolic compounds. These act as natural defence agents, absorbing UV radiation and minimizing oxidative stress to plant cells. The chemical composition of the secretion covering the inflorescences may reflect adaptation and survival mechanisms of these organisms under extreme sun exposure.

2.
Dent Mater ; 38(11): 1679-1688, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36089409

RESUMEN

OBJECTIVE: This study aimed to investigate the role of the incorporation of an antibacterial nanoceramic (AgVO3) on the properties of a restorative dental glass-ceramic. METHOD: A commercially available restorative glass-ceramic, commonly designated as porcelain (IPS d.SIGN) was functionalized with an antibacterial agent (nanostructured ß-AgVO3), synthesized by a hydrothermal route. Both functionalized and pristine samples were processed according to the manufacturer's instructions. All samples were characterized by X-ray diffraction, Rietveld refinement, particle size distribution, Scanning Electron Microscopy, chemical solubility, and Inductively Coupled Plasma Spectroscopy. Their antibacterial potential (Mueller-Hinton test) was analyzed against gram-positive (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli). RESULTS: The commercial glass-ceramic showed leucite (KAlSi2O6) as the only detectable crystalline phase, and, for both strains, no antibacterial activity could be detected in the Mueller-Hinton agar plates test. A monophasic, needle-shaped, and nanometric ß-AgVO3 powder was successfully synthesized by a simple hydrothermal route. After thermal treatment, glass-ceramic samples containing different percentages of ß-AgVO3 showed a second crystalline phase of microline [K0.95(AlSi3O8)]. For modified samples, inhibition halos were easily visible on the Mueller-Hinton test, which ranged from 11.1 ± 0.5 mm to 16.6 ± 0.5 mm and 12.7 ± 0.3 mm to 15.5 ± 0.3 mm in the S. aureus and E.coli cultures, respectively, showing that the halos formed were dose-dependent. Also, increasing the percentage of ß-AgVO3 promoted a significant increase in chemical solubility, from 72 µg/cm2 (samples with 1 wt% of ß-AgVO3) to 136 µg/cm2 (samples with 2 wt% of ß-AgVO3), which was associated with the silver and vanadium ions released from the glass matrix. SIGNIFICANCE: Our in vitro results indicate that IPS d.SIGN, as most of the dental glass-ceramics, do not exhibit antibacterial activity per se. Nonetheless, in this concept test, we demonstrated that it is possible to modify dental veneering materials giving them antibacterial properties by adding at least 2 wt% of ß-AgVO3, a nanomaterial easily synthesized by a simple route.


Asunto(s)
Porcelana Dental , Nanopartículas , Agar , Antibacterianos/farmacología , Cerámica/química , Cerámica/farmacología , Porcelana Dental/química , Ensayo de Materiales , Polvos , Plata/farmacología , Staphylococcus aureus , Propiedades de Superficie , Vanadio
3.
Braz. j. biol ; 79(4): 639-645, Nov. 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1001491

RESUMEN

Abstract In order to evaluate aspects of reproductive biology of the "pequira" ( Bryconamericus stramineus) in the elevator of the Funil Dam - MG, fish capture was carried out from November 2008 to January 2009 and 317 individuals were collected. The mean standard length (SL) of the population was 4.96 cm and mean weight 1.80 g. The females had SL of 5.0 cm, while males had a SL of 4.6 cm. A sex ratio of 2.20: 1 (females: male) was observed. Our results show that 73% of the individuals analyzed were considered adults. The species presented low fecundity, mean of 470.9 oocytes per female and a mean diameter of 221.08 μm, with an increase in oocyte diameter over the evaluation period. The length of the first gonadal maturation was estimated at 5.0 cm. The results obtained in this work suggest that the reproductive cycle of the species occurs in the analyzed period. Although this species does not have migratory reproductive habits, the presence of adults in the reproductive stage was observed in the transposition area, which suggests a search for new environments for spawning.


Resumo Com o objetivo de avaliar aspectos da biologia reprodutiva da pequira Bryconamericus stramineus no elevador da represa do Funil - MG foram realizadas capturas entre os meses de novembro de 2008 a janeiro de 2009, sendo coletados 317 indivíduos. O comprimento padrão (CP) médio da população foi de 4,96 cm e peso médio de 1,80 g. As fêmeas apresentaram CP de 5,0 cm, enquanto que os machos obtiveram um CP de 4,6 cm. Foi observada proporção sexual de 2,20:1(fêmeas:macho). Dos indivíduos analisados, 73% foram considerados adultos. A espécie apresentou baixa fecundidade, com média de 470,9 ovócitos por fêmea e diâmetro médio de 221,08 μm, ocorrendo aumento no diâmetro de ovócitos com o decorrer do tempo no período avaliado. O comprimento de primeira maturação gonadal foi estimado em 5,0 cm. Os resultados obtidos neste trabalho sugerem que o ciclo reprodutivo da espécie ocorre no período analisado. Embora esta espécie não tenha hábitos reprodutivos migratórios, a presença de adultos no estágio reprodutivo foi observada na área de transposição, o que sugere a busca de novos ambientes para a reprodução.


Asunto(s)
Animales , Femenino , Reproducción/fisiología , Characidae/crecimiento & desarrollo , Characidae/fisiología , Estaciones del Año , Razón de Masculinidad , Brasil , Ríos , Fertilidad
4.
Int Endod J ; 52(5): 716-724, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30481389

RESUMEN

AIM: To evaluate the effectiveness of a solvent (eucalyptol) in improving filling material removal from canals connected by isthmuses, and the additional cleaning effect of a finishing instrument. METHODOLOGY: The mesial canals from 32 mandibular molars (Vertucci's type II morphology) were instrumented and filled with the single-cone technique using Reciproc R25 gutta-percha points (VDW, Munich, Germany) combined with Sealer 26 (Dentsply, Petrópolis, RJ, Brazil). Each root was then subjected to retreatment using the Mtwo instrument system (VDW), with or without a solvent (n = 16 per group). The volume of filling material in the canals was assessed by micro-computed tomographic (micro-CT) scans taken before and after retreatment. Canals with remnants of filling material received a supplementary procedure with the XP-endo Finisher R instrument (FKG Dentaire, La Chaux-de-Fonds, Switzerland), with or without eucalyptol, and another micro-CT scan was taken. All retreatment procedures were performed inside a cabinet under a controlled temperature (37 °C). Filling material removal was evaluated in the 5-mm apical canal system for the canal+isthmus space or the isthmus alone. Statistical analyses were performed to compare the removal of filling material with and without eucalyptol, and after a supplementary approach with XP-endo Finisher R. The level of significance was set at 5% for all statistical tests (P < 0.05). RESULTS: The amount of filling material removed from the canal+isthmus with Mtwo instruments was 83.2% when no solvent was used and 83.8% using the solvent (P > 0.05). When the isthmus area was evaluated separately, most specimens were associated with a reduction in the filling material, with no significant difference between the groups with or without using a solvent (P > 0.05). The supplementary step with XP-endo Finisher R significantly improved removal of filling material from both canal and isthmus area (P < 0.05), regardless of the use of a solvent (P > 0.05). CONCLUSION: The use of eucalyptol did not improve filling material removal from Vertucci's type II molar mesial canals and isthmuses. XP-endo Finisher R significantly enhanced removal of filling material from the canals and isthmuses.


Asunto(s)
Materiales de Obturación del Conducto Radicular , Obturación del Conducto Radicular , Brasil , Instrumentos Dentales , Cavidad Pulpar , Diseño de Equipo , Alemania , Gutapercha , Retratamiento , Preparación del Conducto Radicular , Solventes
5.
Braz J Biol ; 79(4): 639-645, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30379203

RESUMEN

In order to evaluate aspects of reproductive biology of the "pequira" ( Bryconamericus stramineus) in the elevator of the Funil Dam - MG, fish capture was carried out from November 2008 to January 2009 and 317 individuals were collected. The mean standard length (SL) of the population was 4.96 cm and mean weight 1.80 g. The females had SL of 5.0 cm, while males had a SL of 4.6 cm. A sex ratio of 2.20: 1 (females: male) was observed. Our results show that 73% of the individuals analyzed were considered adults. The species presented low fecundity, mean of 470.9 oocytes per female and a mean diameter of 221.08 µm, with an increase in oocyte diameter over the evaluation period. The length of the first gonadal maturation was estimated at 5.0 cm. The results obtained in this work suggest that the reproductive cycle of the species occurs in the analyzed period. Although this species does not have migratory reproductive habits, the presence of adults in the reproductive stage was observed in the transposition area, which suggests a search for new environments for spawning.


Asunto(s)
Characidae , Reproducción/fisiología , Animales , Brasil , Characidae/crecimiento & desarrollo , Characidae/fisiología , Femenino , Fertilidad , Masculino , Ríos , Estaciones del Año , Razón de Masculinidad
6.
Int Endod J ; 52(5): 709-715, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30417931

RESUMEN

AIM: To compare the effects of three instrumentation systems, and a supplementary approach with a finishing instrument, on filling material removal during retreatment of mandibular molar canals. METHODS: Sixty mesial canals from mandibular molars (Vertucci's type IV anatomy) were instrumented, filled and subjected to retreatment. After initial removal of the root canal filling material using the D-RaCe system, the canals were randomly distributed into three groups (n = 20) according to the instrument system used for preparation: the Self-Adjusting File (SAF), TRUShape or XP-endo Shaper. The filling material volume in the apical 5 mm of the canals was assessed by means of micro-computed tomography (micro-CT) before and after retreatment. All specimens with residual filling material were subjected to a supplementary approach with the XP-endo Finisher R instrument and another micro-CT scan was taken. Data on the volumes of filling material and incidence of total removal were compared between groups by the general linear model for paired data and the Fisher's exact test. The effects of the refinement step were evaluated by the Wilcoxon Signed Ranks test. RESULTS: The amount of removed material was 92.4%, 96.9% and 96.9% for the SAF, TRUShape and XP-endo Shaper, respectively. There were no significant differences between them (P > 0.05). Canals were completely cleaned of filling material in 70% of the specimens for XP-endo Shaper, 55% for SAF and 30% for TRUShape; the difference between XP-endo Shaper and TRUShape was significant (P = 0.03). The supplementary step with the XP-endo Finisher R instrument was associated with additional filling material removal of 38% (P < 0.001). Six more canals were rendered free of filling material after using this finishing instrument. CONCLUSIONS: The tested systems were equally effective in removing the mass of filling material from the apical 5 mm of molar canals. The supplementary step with the XP-endo Finisher R instrument enhanced filling material removal.


Asunto(s)
Materiales de Obturación del Conducto Radicular , Preparación del Conducto Radicular , Cavidad Pulpar , Diente Molar , Retratamiento , Microtomografía por Rayos X
7.
Int Endod J ; 51(6): 684-690, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29112281

RESUMEN

AIM: To evaluate the effects of progressive apical enlargement on the amount of unprepared root canal surface area and remaining dentine thickness. METHODOLOGY: The root canals of 30 extracted mandibular incisors with Vertucci's type I configuration were instrumented with rotary HyFlex CM instruments (Coltene-Whaledent, Altstätten, Switzerland) up to 4 instruments larger than the first one that bound at the working length (WL). Teeth were scanned in a micro-computed tomography (micro-CT) device before canal preparation and after instrumentation with the 2nd, 3rd and 4th larger instruments. The amount of unprepared surface area in the full canal or in the apical 4 mm as well as the remaining dentine thickness at 10 mm from the WL were calculated and compared. The general linear model for repeated measures adjusted by Bonferroni's post hoc test was used for statistic analysis. RESULTS: There was a significant reduction in the amount of unprepared areas after each increase in preparation size (P < 0.01). This was observed for both the full canal length and the 4-mm apical segment. The amount of remaining dentine was also significantly reduced after each file size (P < 0.01). However, dentine thickness always remained greater than 1 mm, even after using the largest instrument. CONCLUSION: Apical preparations up to 4 instruments larger than the first one to bind at the WL caused a significant progressive reduction in the unprepared canal area.


Asunto(s)
Cavidad Pulpar/diagnóstico por imagen , Preparación del Conducto Radicular/instrumentación , Ápice del Diente/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen , Microtomografía por Rayos X , Humanos , Técnicas In Vitro , Incisivo
8.
Int Endod J ; 51(5): 501-508, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-28196289

RESUMEN

AIM: To microscopically examine the cleanliness of root canal walls that remained unprepared as revealed by micro-CT. METHODOLOGY: The root canals of 10 freshly extracted mandibular premolars with necrotic pulps and apical periodontitis along with the mesiobuccal canals of 11 mandibular molars with vital pulps were prepared using Reciproc instruments R40 and R25, respectively, and 2.5% sodium hypochlorite irrigation. Specimens were scanned in micro-CT before and after preparation, and the unprepared areas were identified. The outer root surface corresponding to the untouched areas was marked on each root third to guide further analysis using histological (for teeth with vital pulps) and scanning electron microscopic (SEM; for necrotic teeth) examination. In the teeth with vital pulps, the root canal area occupied by tissue remnants was calculated. In SEM analysis of teeth with necrotic pulps, scores were attributed for the amount of debris on the untouched areas. RESULTS: The proportion of unprepared areas in the mesiobuccal molar canals was 18.1% and 9.6% over the full canal length and apical canal, respectively. In premolars, corresponding figures were 34.6% and 17.6%, respectively. Histological analysis of canals with vital pulps revealed tissue remnants over the untouched walls almost exclusively in the apical canal. SEM analysis of the canals with necrotic pulps revealed debris along the untouched walls in all root canal thirds. CONCLUSION: The areas that remain untouched by Reciproc instruments used with 2.5% NaOCl irrigation as revealed by micro-CT analysis were usually covered with debris, in the form of pulp tissue remnants, bacteria and dentine chips, especially in the apical root canal.


Asunto(s)
Cavidad Pulpar/patología , Cavidad Pulpar/diagnóstico por imagen , Cavidad Pulpar/ultraestructura , Necrosis de la Pulpa Dental/patología , Humanos , Microscopía Electrónica de Rastreo , Periodontitis Periapical/patología , Preparación del Conducto Radicular , Microtomografía por Rayos X
9.
Theriogenology ; 97: 67-72, 2017 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-28583610

RESUMEN

As production of in vitro (IVP) bovine embryos steadily increases, the sanitary risk associated with IVP embryos remains a concern. One of the greatest concerns is how BVDV may be transmitted through IVP embryos. The objective of this study was to evaluate the effects caused by BVDV-1, BVDV-2 and Hobi-like virus exposure during in vitro maturation on embryo development and viral infection. Abittior-derived oocytes were randomly assigned for in vitro maturation with serial concentrations of BVDV-1 (3.12 × 102 - 2.50 × 103 TCID50/100 µL), BVDV-2 (6.25 × 101 - 5.20 × 102 TCID50/100 µL) or Hobi-like virus (1.90 × 102 - 1.58 × 103 TCID50/100 µL) for 22-24 h. After maturation, oocytes were fertilized and embryo cultured following standard in vitro procedures. Embryo development was evaluated and percentage of respective, positive BVDV degenerated and viable embryos were evaluated by RT-qPCR. No concentration of BVDV-1 altered embryo development as measured by cleavage and blastocyst rates, compared to negative control group. However 100% of degenerated embryos and 50-100% of viable embryos tested positive for BVDV-1, depending on the viral concentration. BVDV-2 exposed oocytes had higher cleavage rates than the negative control group (60.2-64.1% vs 49.8%; P = 0.003-0.032). However, no difference was detected for blastocyst rates. In aadition, 100% of degenerated embryos and 20-50% of viable embryos tested positive for BVDV-2. Hobi-like virus treated oocytes had reduced cleavage rates for the three highest viral concentrations (33.3-38.0% vs 49.8% for negative controls; P ≤ 0.001-0.014). Blastocyst rates were only reduced in the 7.9 × 102 Hobi-like virus concentration (6.9 ± 0.9% vs 15.1 ± 1.6%; P = 0.009), when calculated by oocyte number. 50-80% of degenerated embryos tested positive for Hobi-like virus. No viable embryos from the Hobi-like virus treated oocytes tested positive. These results suggest that IVP embryos from BVDV-1 and -2 infected oocytes develop normally, but carry the virus. However, Hobi-like virus infected oocytes had reduced cleavage and cause pre-implantation embryo loss, but viable embryos did not carry the virus.


Asunto(s)
Bovinos , Desarrollo Embrionario/fisiología , Oocitos/fisiología , Oocitos/virología , Infecciones por Pestivirus/embriología , Pestivirus/fisiología , Animales , Virus de la Diarrea Viral Bovina Tipo 1/fisiología , Virus de la Diarrea Viral Bovina Tipo 2/fisiología , Técnicas de Cultivo de Embriones/veterinaria , Fertilización In Vitro/veterinaria
10.
Plant Biol (Stuttg) ; 19(2): 140-146, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27870312

RESUMEN

Mixed cross and self-pollen load on the stigma (mixed pollination) of species with late-acting self-incompatibility system (LSI) can lead to self-fertilized seed production. This "cryptic self-fertility" may allow selfed seedling development in species otherwise largely self-sterile. Our aims were to check if mixed pollinations would lead to fruit set in LSI Adenocalymma peregrinum, and test for evidence of early-acting inbreeding depression in putative selfed seeds from mixed pollinations. Experimental pollinations were carried out in a natural population. Fruit and seed set from self-, cross and mixed pollinations were analysed. Further germination tests were carried out for the seeds obtained from treatments. Our results confirm self-incompatibility, and fruit set from cross-pollinations was three-fold that from mixed pollinations. This low fruit set in mixed pollinations is most likely due to a greater number of self- than cross-fertilized ovules, which promotes LSI action and pistil abortion. Likewise, higher percentage of empty seeds in surviving fruits from mixed pollinations compared with cross-pollinations is probably due to ovule discounting caused by self-fertilization. Moreover, germinability of seeds with developed embryos was lower in fruits from mixed than from cross-pollinations, and the non-viable seeds from mixed pollinations showed one-third of the mass of those from cross-pollinations. The great number of empty seeds, lower germinability, lower mass of non-viable seeds, and higher variation in seed mass distribution in mixed pollinations, strongly suggests early-acing inbreeding depression in putative selfed seeds. In this sense, LSI and inbreeding depression acting together probably constrain self-fertilized seedling establishment in A. peregrinum.


Asunto(s)
Bignoniaceae/fisiología , Depresión Endogámica , Polinización , Autoincompatibilidad en las Plantas con Flores , Bignoniaceae/genética , Bignoniaceae/crecimiento & desarrollo , Biomasa , Flores/genética , Flores/crecimiento & desarrollo , Flores/fisiología , Frutas/genética , Frutas/crecimiento & desarrollo , Frutas/fisiología , Germinación , Óvulo Vegetal/genética , Óvulo Vegetal/crecimiento & desarrollo , Óvulo Vegetal/fisiología , Polen/genética , Polen/crecimiento & desarrollo , Polen/fisiología , Plantones/genética , Plantones/crecimiento & desarrollo , Plantones/fisiología , Semillas/genética , Semillas/crecimiento & desarrollo , Semillas/fisiología , Autofecundación
11.
Aust Dent J ; 62(2): 223-227, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27471145

RESUMEN

Radiolucent or hypodense lesions in the crown of unerupted teeth may be due to pre-eruptive intracoronal resorption. Clinicians must be aware of this risk so that they can diagnose and appropriately treat this condition. The purpose of this study is to present a well-documented clinical case of pre-eruptive intracoronal resorption in an impacted third upper left molar of a 63 year old female patient. This was an unexpected finding, which occurred after cone-beam computed tomography was used to investigate the first upper left molar, which had an acute periradicular abscess. A multidisciplinary team followed up the case to describe clinical, radiographic and histological findings. The available treatment options were discussed, and the tooth extraction was the option chosen. Previous case studies describing such resorption in third upper molars have not been reported. This case shows that all permanent teeth in a pre-eruptive stage must be analysed radiographically to detect early pre-eruptive intracoronal resorption.


Asunto(s)
Corona del Diente/patología , Resorción Dentaria , Diente no Erupcionado/patología , Absceso/diagnóstico por imagen , Absceso/etiología , Tomografía Computarizada de Haz Cónico , Dentición Permanente , Femenino , Humanos , Persona de Mediana Edad , Diente Molar , Tercer Molar , Tomografía Computarizada por Rayos X , Corona del Diente/diagnóstico por imagen , Erupción Dental , Extracción Dental , Diente Impactado/patología
12.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467231

RESUMEN

Abstract In order to evaluate aspects of reproductive biology of the pequira ( Bryconamericus stramineus) in the elevator of the Funil Dam - MG, fish capture was carried out from November 2008 to January 2009 and 317 individuals were collected. The mean standard length (SL) of the population was 4.96 cm and mean weight 1.80 g. The females had SL of 5.0 cm, while males had a SL of 4.6 cm. A sex ratio of 2.20: 1 (females: male) was observed. Our results show that 73% of the individuals analyzed were considered adults. The species presented low fecundity, mean of 470.9 oocytes per female and a mean diameter of 221.08 m, with an increase in oocyte diameter over the evaluation period. The length of the first gonadal maturation was estimated at 5.0 cm. The results obtained in this work suggest that the reproductive cycle of the species occurs in the analyzed period. Although this species does not have migratory reproductive habits, the presence of adults in the reproductive stage was observed in the transposition area, which suggests a search for new environments for spawning.


Resumo Com o objetivo de avaliar aspectos da biologia reprodutiva da pequira Bryconamericus stramineus no elevador da represa do Funil - MG foram realizadas capturas entre os meses de novembro de 2008 a janeiro de 2009, sendo coletados 317 indivíduos. O comprimento padrão (CP) médio da população foi de 4,96 cm e peso médio de 1,80 g. As fêmeas apresentaram CP de 5,0 cm, enquanto que os machos obtiveram um CP de 4,6 cm. Foi observada proporção sexual de 2,20:1(fêmeas:macho). Dos indivíduos analisados, 73% foram considerados adultos. A espécie apresentou baixa fecundidade, com média de 470,9 ovócitos por fêmea e diâmetro médio de 221,08 m, ocorrendo aumento no diâmetro de ovócitos com o decorrer do tempo no período avaliado. O comprimento de primeira maturação gonadal foi estimado em 5,0 cm. Os resultados obtidos neste trabalho sugerem que o ciclo reprodutivo da espécie ocorre no período analisado. Embora esta espécie não tenha hábitos reprodutivos migratórios, a presença de adultos no estágio reprodutivo foi observada na área de transposição, o que sugere a busca de novos ambientes para a reprodução.

13.
Genet Mol Res ; 15(4)2016 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-27966759

RESUMEN

Myrcia lundiana Kiaersk. is a tree of the family Myrtaceae found in tropical and subtropical areas of the southern hemisphere that produces essential oil. The aim of this study was to characterize the genetic diversity of M. lundiana plants from a native population of Parque Nacional de Itabaiana, using inter-simple sequence repeat molecular markers. Thirty-five primers were tested, 20 of which were polymorphic, resulting in 135 polymorphic and informative bands. Results of the cluster analysis, obtained using the unweighted pair group method with arithmetic mean, grouped plants into three clusters: Cluster I - MLU001, MLU002, MLU003, MLU004, MLU005, MLU006, MLU018, MLU019, MLU020, MLU021, MLU022; MLU008, MLU011, MLU012, MLU014, MLU015, MLU017, MLU026, and MLU028; Cluster II - MLU007, MLU009, MLU010, MLU013, and MLU016; and Cluster III - MLU023, MLU024, MLU025, and MLU027. Jaccard similarity coefficients for pair-wise comparisons of plants ranged between 0.15 and 0.87. MLU014 and MLU015 presented low genetic diversity, with a similarity index of 0.87. Conversely, MLU007 and MLU019 presented high diversity, with a similarity index of 0.15. According to the structure analysis, three distinct clusters were formed. Genetic diversity of M. lundiana plants was intermediate, and expansion of its genetic diversity is necessary. MLU026 and MLU028 are the most suitable for selection in breeding programs, since they clearly represent all of the diversity present in these plants. Moreover, these results provide important information on the existing genetic variability, highlighting the importance of Parque Nacional de Itabaiana for the conservation of this species.


Asunto(s)
Variación Genética , Repeticiones de Microsatélite , Myrtaceae/genética , Análisis por Conglomerados , Conservación de los Recursos Naturales , ADN de Plantas/genética , Marcadores Genéticos/genética , Genética de Población , Filogenia , Fitomejoramiento
14.
Int Endod J ; 49(11): 1079-1087, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26459183

RESUMEN

AIM: To evaluate the removal of accumulated hard-tissue debris (AHTD) from the root canal system of mandibular molars by positive and negative pressure irrigation systems, using micro-CT imaging analysis. METHODOLOGY: Mandibular molars with a single canal in the distal root and 2 canals connected by an isthmus in the mesial root were matched based on similar morphological dimensions using micro-CT evaluation and assigned to 2 experimental groups (n = 20 mesial and 10 distal canals), according to the irrigation protocol: apical positive (conventional irrigation) or negative (EndoVac system) pressure. Changes in root canal volume and surface area as well as percentage of uninstrumented canal wall surface and accumulated hard-tissue debris (AHTD) after canal preparation were compared statistically using the independent sample t-test and Mann-Whitney U-test, with the significance level set at 5%. RESULTS: Volume, surface area and percentage of static voxels in either mesial or distal root canal systems were not significantly different between groups before or after root canal preparation (P > 0.05). After preparation, AHTD was not observed in the distal canal of both groups. However, in the mesial root canal system, the conventional irrigation group was associated with a significantly higher median percentage of AHTD (11.48%; IQR: 5.9-22.6; range: 1.86-41.98) than the EndoVac group (3.40%; IQR: 1.5-7.3; range: 0.82-12.84) (P < 0.05). CONCLUSIONS: Neither irrigation protocol succeeded in rendering the mesial canal system free of AHTD; however, apical negative pressure irrigation resulted in lower levels of AHTD than conventional irrigation.


Asunto(s)
Diente Molar/anatomía & histología , Preparación del Conducto Radicular/métodos , Raíz del Diente/anatomía & histología , Cavidad Pulpar/anatomía & histología , Cavidad Pulpar/diagnóstico por imagen , Humanos , Modelos Dentales , Diente Molar/diagnóstico por imagen , Irrigantes del Conducto Radicular , Raíz del Diente/diagnóstico por imagen , Microtomografía por Rayos X
15.
Rev. bras. plantas med ; 18(1,supl.1): 336-340, 2016. tab
Artículo en Inglés | LILACS | ID: lil-782977

RESUMEN

ABSTRACT Hyptis pectinata, popularly known as “sambacaitá”, is a native medicinal herb used by local people for treating disease. Its pharmacological, antimicrobial, and medicinal properties have been reported in several studies. The essential oil of the leaves is rich in terpene compounds responsible for its properties. Because there are factors that can influence the chemical composition of essential oils, the objective of this study was to evaluate the influence of storage on Hyptis pectinata essential oil for 360 days at two different temperatures. The essential oil was distilled from dried leaves of seven-month-old plants using the hydrodistillation method, and the chemical composition was determined using GC-MS and GC/FID. The effects of storage on the essential oil Hyptis pectinata were tested over the course of a year (0, 15, 30, 60, 90, 120, 150, 180, 240, 300, and 360 days), using two temperatures: room (±32ºC) and freezer (-20ºC). The predominant compounds in the essential oil are β–caryophyllene, caryophyllene oxide, and germancrene D. The concentration of the chemical constituents of the essential oil varied depending on the storage temperature, and over the 360 days. The storage of the essential oil at room temperature over one year resulted in higher concentrations of β-elemene, α-copaene, germacrene D, caryophyllene oxide, and (E,E)-α-farnesene and lower content of α-humulene and β-caryophyllene, compared to the results obtained from storing the essential oil in a freezer. These results indicate that the essential oil should be stored in a freezer, which provides greater stability to the concentration of the chemical constituents.


RESUMO Hyptis pectinata, conhecida popularmente como Sambacaitá é uma erva medicinal nativa utilizada pela população local para o tratamento de enfermidades, cujas propriedades farmacológicas, antimicrobianas e medicinais foram relatadas em diversos estudos. O óleo essencial das folhas é rico em compostos terpênicos responsáveis pelas suas propriedades. Devido à existência de fatores que podem influenciar a composição química dos óleos essenciais, o objetivo deste trabalho foi avaliar a influência do armazenamento do óleo essencial Hyptis pectinata durante 360 dias em duas temperaturas diferentes. O óleo essencial foi destilado a partir de folhas secas de plantas de sete meses de idade, utilizando o método de hidrodestilação e a composição química foi determinada usando CG-EM e CG-DIC. Os efeitos do armazenamento no óleo essencial Hyptis pectinata foram testados ao longo de um ano (0, 15, 30, 60, 90, 120, 150, 180, 240, 300 e 360 dias), utilizando duas temperaturas: ambiente (±32ºC) e freezer (-20ºC). Os compostos predominantes no óleo essencial foram o β-cariofileno, óxido de cariofileno e germancreno D e houve variação na concentração dos constituintes químicos do óleo essencial, dependendo da temperatura de armazenamento, bem como ao longo dos 360 dias. O armazenamento do óleo essencial, à temperatura ambiente ao longo de um ano resultou em maiores concentrações de β-elemeno, α-copaeno, germacreno D, óxido de cariofileno e (E, E) -α-farneseno e menores teores de α-humuleno e β-cariofileno, quando comparado com os resultados obtidos a partir de armazenamento do óleo essencial no freezer. Estes resultados indicam que o óleo essencial deve ser estocado no freezer, o que propicia maior estabilidade na concentração dos constituintes químicos.


Asunto(s)
Temperatura , Aceites Volátiles/análisis , Química , Hyptis/clasificación , Almacenamiento de Productos , Plantas Medicinales/clasificación , Productos Agrícolas
17.
PLoS One ; 10(5): e0127515, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26010093

RESUMEN

BACKGROUND: There is growing interest in sex differences and RAS components. However, whether gender influences cardiac angiotensin I-converting enzyme (ACE) and angiotensin-converting enzyme 2 (ACE2) activity is still unknown. In the present work, we determined the relationship between ACE and ACE2 activity, left ventricular function and gender in spontaneously hypertensive rats (SHRs). METHODOLOGY/PRINCIPAL FINDINGS: Twelve-week-old female (F) and male (M) SHRs were divided into 2 experimental groups (n = 7 in each group): sham (S) and gonadectomized (G). Fifty days after gonadectomy, we measured positive and negative first derivatives (dP/dt maximum left ventricle (LV) and dP/dt minimum LV, respectively), hypertrophy (morphometric analysis) and ACE and ACE2 catalytic activity (fluorimetrically). Expression of calcium handling proteins was measured by western blot. Male rats exhibited higher cardiac ACE and ACE2 activity as well as hypertrophy compared to female rats. Orchiectomy decreased the activity of these enzymes and hypertrophy, while ovariectomy increased hypertrophy and ACE2, but did not change ACE activity. For cardiac function, the male sham group had a lower +dP/dt than the female sham group. After gonadectomy, the +dP/dt increased in males and reduced in females. The male sham group had a lower -dP/dt than the female group. After gonadectomy, the -dP/dt increased in the male and decreased in the female groups when compared to the sham group. No difference was observed among the groups in SERCA2a protein expression. Gonadectomy increased protein expression of PLB (phospholamban) and the PLB to SERCA2a ratio in female rats, but did not change in male rats. CONCLUSION: Ovariectomy leads to increased cardiac hypertrophy, ACE2 activity, PLB expression and PLB to SERCA2a ratio, and worsening of hemodynamic variables, whereas in males the removal of testosterone has the opposite effects on RAS components.


Asunto(s)
Cardiomegalia/enzimología , Cardiomegalia/fisiopatología , Hormonas Esteroides Gonadales/farmacología , Hipertensión/enzimología , Contracción Miocárdica/efectos de los fármacos , Peptidil-Dipeptidasa A/metabolismo , Enzima Convertidora de Angiotensina 2 , Animales , Presión Sanguínea/efectos de los fármacos , Western Blotting , Peso Corporal/efectos de los fármacos , Cardiomegalia/complicaciones , Densitometría , Femenino , Gónadas/efectos de los fármacos , Gónadas/cirugía , Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/patología , Ventrículos Cardíacos/fisiopatología , Hemodinámica/efectos de los fármacos , Hipertensión/complicaciones , Hipertensión/fisiopatología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas Endogámicas SHR , Sístole/efectos de los fármacos
18.
Int Endod J ; 48(12): 1129-36, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25400256

RESUMEN

AIM: To investigate changes in three-dimensional geometry, in various cross-sectional morphological parameters and in the centring ability of root canals prepared with different preparation systems using microcomputed tomographic imaging technology. METHODOLOGY: Sixty-four mesial canals of mandibular molars were matched based on similar morphological dimensions using micro-CT evaluation and assigned to four experimental groups (n = 16), according to the canal preparation technique: Reciproc, WaveOne, Twisted File and HyFlex CM systems. Changes in several 2D (area, perimeter, form factor, roundness, minor and major diameter) and 3D [volume, surface area, structure model index (SMI)] morphological parameters, as well as canal transportation, were compared with preoperative values using Kruskal-Wallis and anovapost hoc Tukey's tests with the significance level set at 5%. RESULTS: Preparation significantly increased all tested parameters in the experimental groups. No significant differences were observed between groups regarding changes in volume, surface area, SMI, form factor and roundness of the root canal after preparation (P > 0.05). In the apical third, the Reciproc group had significantly greater changes in canal area, perimeter, major and minor diameters than the other groups (P < 0.05). Overall, the Twisted File and HyFlex CM systems were associated with significantly less transportation than the reciprocating instruments, Reciproc and WaveOne (P < 0.05). CONCLUSIONS: Shaping procedures led to the enlargement of the root canal space with no evidence of significant preparation errors. Changes in 3D parameters were not different between groups whilst, in the apical third, Reciproc was associated with significantly greater changes in several 2D parameters compared to the other groups. Twisted File and HyFlex CM systems were able to maintain the original canal anatomy with less canal transportation than Reciproc and WaveOne; however, these differences are unlikely to be of clinical significance.


Asunto(s)
Diente Molar/diagnóstico por imagen , Diente Molar/cirugía , Preparación del Conducto Radicular/instrumentación , Microtomografía por Rayos X , Instrumentos Dentales , Diseño de Equipo , Humanos , Técnicas In Vitro
19.
Genet Mol Res ; 12(1): 597-609, 2013 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-23512677

RESUMEN

Gossypium mustelinum is the only cotton species native to Brazil; it is endemic to the semi-arid region of the northeast. The populations are found near perennial and semi-perennial sources of water, such as ponds or pools in intermittent streams. Problems with in situ conservation derive from human interference in its habitat, mainly because of excessive cattle grazing and deforestation. Establishing efficient strategies for in situ conservation requires knowledge of the genetic structure of the populations. We evaluated the structure and genetic variability of populations of G. mustelinum in the Tocó and Capivara Rivers (State of Bahia). Two hundred and eighteen mature G. mustelinum plants were genotyped with SSR markers. The molecular data were used to estimate the allelic frequencies, the heterozygosity, the F statistics, and the genetic distance among the populations and among individuals. We found high genetic diversity among the populations. The FST indexes for each population were also high and strongly correlated with physical distance. The high estimated level of endogamy and the low observed heterozygosity are indicative that the populations reproduce mainly by self-fertilization and crosses between related individuals. Consequently, strategies for in situ preservation should include at least three occurrence sites of G. mustelinum from each population. For ex situ conservation, the collections should include as many sites as possible.


Asunto(s)
Ecosistema , Variación Genética , Gossypium/genética , Repeticiones de Microsatélite/genética , Alelos , Animales , Brasil , Bovinos , ADN de Plantas/química , ADN de Plantas/genética , Frecuencia de los Genes , Estructuras Genéticas , Genética de Población , Genotipo , Geografía , Gossypium/clasificación , Gossypium/crecimiento & desarrollo , Humanos , Filogenia , Ríos , Análisis de Secuencia de ADN
20.
Braz J Med Biol Res ; 46(2): 171-7, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23369979

RESUMEN

Sex hormones modulate the action of both cytokines and the renin-angiotensin system. However, the effects of angiotensin I-converting enzyme (ACE) on the proinflammatory and anti-inflammatory cytokine levels in male and female spontaneously hypertensive rats (SHR) are unclear. We determined the relationship between ACE activity, cytokine levels and sex differences in SHR. Female (F) and male (M) SHR were divided into 4 experimental groups each (n = 7): sham + vehicle (SV), sham + enalapril (10 mg/kg body weight by gavage), castrated + vehicle, and castrated + enalapril. Treatment began 21 days after castration and continued for 30 days. Serum cytokine levels (ELISA) and ACE activity (fluorimetry) were measured. Male rats exhibited a higher serum ACE activity than female rats. Castration reduced serum ACE in males but did not affect it in females. Enalapril reduced serum ACE in all groups. IL-10 (FSV = 16.4 ± 1.1 pg/mL; MSV = 12.8 ± 1.2 pg/mL), TNF-α (FSV = 16.6 ± 1.2 pg/mL; MSV = 12.8 ± 1 pg/mL) and IL-6 (FSV = 10.3 ± 0.2 pg/mL; MSV = 7.2 ± 0.2 pg/mL) levels were higher in females than in males. Ovariectomy reduced all cytokine levels and orchiectomy reduced IL-6 but increased IL-10 concentrations in males. Castration eliminated the differences in all inflammatory cytokine levels (IL-6 and TNF-α) between males and females. Enalapril increased IL-10 in all groups and reduced IL-6 in SV rats. In conclusion, serum ACE inhibition by enalapril eliminated the sexual dimorphisms of cytokine levels in SV animals, which suggests that enalapril exerts systemic anti-inflammatory and anti-hypertensive effects.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Enalapril/farmacología , Hipertensión/sangre , Interleucina-10/sangre , Interleucina-6/sangre , Factor de Necrosis Tumoral alfa/sangre , Animales , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Femenino , Hipertensión/fisiopatología , Masculino , Ovariectomía , Ratas Endogámicas SHR , Factores Sexuales
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