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1.
Bone ; 138: 115447, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32454257

RESUMEN

Biomineralization is remarkably diverse and provides myriad functions across many organismal systems. Biomineralization processes typically produce hardened, hierarchically organized structures usually having nanostructured mineral assemblies that are formed through inorganic-organic (usually protein) interactions. Calcium­carbonate biomineral predominates in structures of small invertebrate organisms abundant in marine environments, particularly in shells (remarkably it is also found in the inner ear otoconia of vertebrates), whereas calcium-phosphate biomineral predominates in the skeletons and dentitions of both marine and terrestrial vertebrates, including humans. Reconciliation of the interplay between organic moieties and inorganic crystals in bones and teeth is a cornerstone of biomineralization research. Key molecular determinants of skeletal and dental mineralization have been identified in health and disease, and in pathologic ectopic calcification, ranging from small molecules such as pyrophosphate, to small membrane-bounded matrix vesicles shed from cells, and to noncollagenous extracellular matrix proteins such as osteopontin and their derived bioactive peptides. Beyond partly knowing the regulatory role of the direct actions of inhibitors on vertebrate mineralization, more recently the importance of their enzymatic removal from the extracellular matrix has become increasingly understood. Great progress has been made in deciphering the relationship between mineralization inhibitors and the enzymes that degrade them, and how adverse changes in this physiologic pathway (such as gene mutations causing disease) result in mineralization defects. Two examples of this are rare skeletal diseases having osteomalacia/odontomalacia (soft bones and teeth) - namely hypophosphatasia (HPP) and X-linked hypophosphatemia (XLH) - where inactivating mutations occur in the gene for the enzymes tissue-nonspecific alkaline phosphatase (TNAP, TNSALP, ALPL) and phosphate-regulating endopeptidase homolog X-linked (PHEX), respectively. Here, we review and provide a concept for how existing and new information now comes together to describe the dual nature of regulation of mineralization - through systemic mineral ion homeostasis involving circulating factors, coupled with molecular determinants operating at the local level in the extracellular matrix. For the local mineralization events in the extracellular matrix, we present a focused concept in skeletal mineralization biology called the Stenciling Principle - a principle (building upon seminal work by Neuman and Fleisch) describing how the action of enzymes to remove tissue-resident inhibitors defines with precision the location and progression of mineralization.


Asunto(s)
Raquitismo Hipofosfatémico Familiar , Hipofosfatasia , Fosfatasa Alcalina , Animales , Huesos , Calcificación Fisiológica , Matriz Extracelular , Humanos , Osteopontina
2.
Braz. j. biol ; 76(2): 526-530, Apr.-June 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-781395

RESUMEN

Abstract This study aimed to evaluate the effect of keeping three couples in the same cage, and the size of adults emerged from small, medium-sized and large pupae (278.67 mg; 333.20 mg and 381.58 mg, respectively), on the reproductive potential of S. eridania (Stoll, 1782) adults, under controlled conditions (25 ± 1 °C, 70% RH and 14 hour photophase). We evaluated the survival, number of copulations, fecundity and fertility of the adult females. The survival of females from these different pupal sizes did not differ statistically, but the survival of males from large pupae was statistically shorter than from small pupae. Fecundity differed significantly and correlated positively with size. The number of effective copulations (espematophores) and fertility did not vary significantly with pupal size. Our results emphasize the importance of indicating the number of copulations and the size of the insects when reproductive parameters are compared.


Resumo Este estudo objetivou avaliar o efeito de confinar três casais em cada gaiola e o tamanho de adultos emergidos de pupas pequenas, medias e grandes (278,67 mg, 333,20 mg e 381,58 mg, respectivamente), sobre o potencial reprodutivo de S. eridania (Stoll, 1782), em condições controladas (25 ± 1 °C, 70% UR e 14 horas de fotofase). Avaliou-se a sobrevivência, o número de cópulas, fecundidade e fertilidade dos adultos. A sobrevivência não diferiu significativamente entre fêmeas provenientes de pupas de diferentes tamanhos, mas os machos oriundos de pupas grandes tiveram sobrevivência significativamente menor que os demais tamanhos. A fecundidade diferiu significativamente e correlacionou-se positivamente com o tamanho. O número de cópulas (espematóforos) e a fertilidade não variaram em função do peso pupal. Os resultados enfatizam a importância de indicar o número de cópulas e o tamanho dos insetos estudados para que comparações entre os parâmetros reprodutivos possam ser efetuadas.


Asunto(s)
Animales , Masculino , Femenino , Spodoptera/crecimiento & desarrollo , Spodoptera/fisiología , Pupa/fisiología , Ambiente , Fenómenos Fisiológicos Reproductivos , Fertilidad , Larva/fisiología
3.
Braz J Biol ; 76(2): 526-30, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26959952

RESUMEN

This study aimed to evaluate the effect of keeping three couples in the same cage, and the size of adults emerged from small, medium-sized and large pupae (278.67 mg; 333.20 mg and 381.58 mg, respectively), on the reproductive potential of S. eridania (Stoll, 1782) adults, under controlled conditions (25 ± 1 °C, 70% RH and 14 hour photophase). We evaluated the survival, number of copulations, fecundity and fertility of the adult females. The survival of females from these different pupal sizes did not differ statistically, but the survival of males from large pupae was statistically shorter than from small pupae. Fecundity differed significantly and correlated positively with size. The number of effective copulations (espematophores) and fertility did not vary significantly with pupal size. Our results emphasize the importance of indicating the number of copulations and the size of the insects when reproductive parameters are compared.


Asunto(s)
Spodoptera , Animales , Ambiente , Femenino , Fertilidad , Larva/fisiología , Masculino , Pupa/fisiología , Fenómenos Fisiológicos Reproductivos , Spodoptera/crecimiento & desarrollo , Spodoptera/fisiología
4.
Neotrop Entomol ; 45(1): 22-7, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26429580

RESUMEN

We provide detailed temporal and morphological parameters of the immature stages of Spodoptera dolichos (Fabricius) larvae fed on artificial diet under controlled conditions (25 ± 1 °C, 70 ± 10% RH, and 14 h photophase). The viability of the egg, larval, pupal, and prepupal stages was 97.5%, 97.0%, 93.1%, and 98.9%, respectively. The average duration of the egg, larval, prepupal, and pupal stages was 5.0, 23.4, 3.2, and 21.5 days, respectively. Females took longer at the larval stage than males, with 10.5% of them having seven instars. The growth rate of female larvae that developed through six and seven instars was 1.72 and 1.54, respectively. Female pupae were significantly larger, exhibiting slower development than males.


Asunto(s)
Spodoptera/crecimiento & desarrollo , Animales , Femenino , Larva/crecimiento & desarrollo , Masculino , Pupa/crecimiento & desarrollo
5.
Biochem Mol Biol Educ ; 40(3): 204-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22615229

RESUMEN

Concepts from disciplines such as Biochemistry, Genetics, Cellular and Molecular Biology are essential to the understanding and treatment of an elevated number of illnesses, but often they are studied separately, with no integration between them. This article proposes a model for basic sciences integration based on problem-based learning (PBL) and compares failure rate, global final grade, approved student final grade, grade distribution and students' satisfaction with teacher conduction between integrated curriculum and traditional learning in health courses from Anhembi Morumbi University-a private institution from Brazil. Comparison between integrated and traditional curriculum was based on students' records obtained from first-year health sciences students. A total of 1,697 records from 2005 to 2007 (nonintegrated curriculum) and 785 records from 2008 (integrated curriculum) were selected for this study and they were necessary to get information about students' grades. Moreover, a questionnaire was applied in order to cover student's satisfaction with teacher conduction. The data presented in this study indicated that the integrated curriculum based on PBL was related to an improvement in student's grades and satisfaction compared with traditional teaching. We believe that the effectiveness in health education will be a combination of "classical" presentation of contents associated to actively involved students in the educational process and methodology based on problems in order to create the stimulus for the undergraduates continue to integrate basic and clinical investigation.


Asunto(s)
Disciplinas de las Ciencias Biológicas/educación , Educación de Pregrado en Medicina/métodos , Aprendizaje Basado en Problemas/métodos , Adolescente , Brasil , Curriculum , Educación de Pregrado en Medicina/estadística & datos numéricos , Evaluación Educacional/estadística & datos numéricos , Humanos , Modelos Educacionales , Satisfacción Personal , Aprendizaje Basado en Problemas/estadística & datos numéricos , Estudiantes/psicología , Encuestas y Cuestionarios , Adulto Joven
6.
Braz J Biol ; 70(4): 931-6, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21180896

RESUMEN

Several insects are harmful to apples grown in Brazil, especially the leafroller Bonagota salubricola (Lepidoptera, Tortricidae), usually controlled with chemical insecticides. The purpose of the present study was to investigate the use of Metarhizium anisopliae strains in the control of the apple leafroller, by assessing their virulence to B. salubricola larvae in bioassays with suspensions of 2 x 105 to 2 x 109 conidia/mL as well as their relationship with protease expression. The most effective strain underwent a compatibility test with chemical insecticides. The M. anisopliae E6 strain showed a good performance, with up to 88% mortality and a LT50 of 1.66 days. The virulence was positively correlated with a higher enzymatic activity. The E6 strain was compatible with tebufenozide, evidencing its potential to control B. salubricola.


Asunto(s)
Ascomicetos/fisiología , Insecticidas , Lepidópteros/parasitología , Metarhizium/fisiología , Control Biológico de Vectores/métodos , Animales , Larva/parasitología , Lepidópteros/enzimología , Factores de Tiempo
7.
Braz J Biol ; 70(4): 1039-46, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21180911

RESUMEN

Samples of the Bacillus thuringiensis (Bt) were collected from soil and insects. Eight isolates were selected from rural soil, 15 from urban soil and 11 from insects. These were evaluated for entomopathogenicity against larvae of Anticarsia gemmatalis and Culex quinquefasciatus. The pathogenicity tests showed that a higher percentage of isolates were active against A. gemmatalis (60%) compared to C. quinquefasciatus (31%). Probit analysis (LC50) indicated that against A. gemmatalis four of the isolates presented values similar to the reference strain against A. gemmatalis, while against C. quinquefasciatus one isolate showed an LC50 similar to the reference strain (IPS-82). SDS-PAGE characterisation of two isolates showed a 27 kDa protein fraction related to the Bt subspecies israelensis cytolytic toxin (cyt) gene. One 130 kDa protein, possibly related to the Bt crystal inclusions (cry1) gene, was identified in the other two isolates, which were more toxic for lepidoptera; another isolate presented a protein of 100 kDa. Some new local Bt isolates had similar LC50 probit values to the reference strains.


Asunto(s)
Bacillus thuringiensis/patogenicidad , Culex/microbiología , Lepidópteros/microbiología , Control Biológico de Vectores/métodos , Animales , Bacillus thuringiensis/química , Bacillus thuringiensis/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Larva/microbiología , Microbiología del Suelo
8.
Genet Mol Res ; 9(3): 1421-30, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20662157

RESUMEN

Pathogenicity of strains of the entomopathogenic fungus Beauveria bassiana and endophytic strains of Beauveria sp against the bovine tick Rhipicephalus (Boophilus) microplus was tested in laboratory bioassays and under field conditions. Suspensions containing 10(5), 10(7) and 10(9) conidia/mL were prepared of each fungal strain for laboratory bioassays. The ticks were maintained at 28 degrees C, 90 +/- 5% relative humidity, and the following variables were evaluated: initial female weight, egg weight, hatching percentage, reproductive efficiency, and percentage control. For tests under field conditions, a Beauveria suspension containing 10(6) conidia/mL was sprayed on tick-infested cows. After 72 h, the ticks were collected to estimate mortality under field conditions. Laboratory bioassays showed a mortality of 20 to 50% of the ticks seven days after inoculation with 10(7) Beauveria conidia/mL. Under field conditions 10(6) Beauveria conidia/mL induced 18-32% mortality. All Beauveria strains were effective in biological control of R. (Boophilus) microplus under laboratory and field test conditions. This is the first demonstration that endophytic fungi can be used for biological control of the cattle tick; this could help reduce environmental contamination by diminishing the need for chemical acaricides. Two endophytic strains were isolated from maize leaves and characterized by molecular sequencing of 5.8S rDNA ITS1 and ITS2 and morphological analyses of conidia. We found that these two endophytic Beauveria isolates, designated B95 and B157, are close to Beauveria amorpha.


Asunto(s)
Beauveria/patogenicidad , Control Biológico de Vectores , Rhipicephalus/microbiología , Animales , Bioensayo , Bovinos , Femenino , Dosificación Letal Mediana , Masculino , Datos de Secuencia Molecular , Filogenia , Reproducción/fisiología , Esporas Fúngicas/patogenicidad
9.
Braz J Biol ; 70(2): 373-80, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20549065

RESUMEN

Aiming to contribute to knowledge of the immature instars of Neotropical Lepidoptera, this study details the morphology of the egg and last instar larvae of Aucula magnifica (Schaus, 1904) (Lepidoptera: Noctuidae: Agaristinae), emphasising the structures of the corium and the chaetotaxy. There is also a report of the occurrence of entomopathogenic action of Nomuraea rileyi (Farlow) Samson fungi on the larva.


Asunto(s)
Hypocreales/aislamiento & purificación , Lepidópteros/anatomía & histología , Óvulo , Animales , Femenino , Larva/anatomía & histología , Larva/microbiología , Lepidópteros/clasificación , Lepidópteros/microbiología
10.
Am J Vet Res ; 62(9): 1478-80, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11560280

RESUMEN

OBJECTIVE: To evaluate the pathogenicity of 4 strains of the entomopathogenic fungi Metarhizium flavoviride var flavoviride and Metarhizium anisopliae var anisopliae in vitro against the bovine tick Boophilus microplus. SAMPLE POPULATION: 300 B. microplus females were used for each series of 5 conidial suspensions of the 4 fungal strains; a control group of 60 females was treated with sterilized water. PROCEDURE: For each fungal strain, sporulating cultures were used to produce conidial suspensions containing 10(4), 10(5), 10(6), 10(7), and 10(8) conidia/ml. A bioassay was performed by immersing B. microplus females in conidial suspensions; the procedure was repeated with a new group of 60 females for each dilution (a total of 300). A control group was immersed in the same volume of sterilized distilled water. Ticks were maintained at 27 C and 80% relative humidity for 7 days, and the following variables were evaluated: weight before egging, egging weight, percentage eclosion, reproductive efficiency, and percentage control. RESULTS: A low index of eclosion was found in the treated groups, with a progressive decrease in percentage eclosion (control = 100%) with increased conidial concentration. The highest level of effectiveness of biocontrol was detected in groups treated with concentrations of 10(7) and 10(8) conidia/ml. CONCLUSIONS AND CLINICAL RELEVANCE: Strains of the entomopathogenic fungi M. anisopliae var anisopliae and M. flavoviride var flavoviride were effective as biological control agents against B. microplus, with M. flavoviride strain CG-291 being the most effective. The pathogenicity of these strains and the development of an application method for this fungus for control of ticks may result in improved animal productivity and a reduction in environmental pollution through the use of fewer chemical insecticides.


Asunto(s)
Hongos/patogenicidad , Garrapatas/microbiología , Animales , Peso Corporal , Bovinos , Femenino , Masculino , Control Biológico de Vectores/métodos
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