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1.
Braz. j. biol ; Braz. j. biol;80(4): 777-782, Oct.-Dec. 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1142524

RESUMEN

Abstract The objective of this study was to evaluate the internal morphology of seeds of Campomanesia pubescens (Mart. ex DC.) O. Berg with varying water content through X-ray image analysis, and correlate the images with the germination of these seeds. Fruits were collected in Jataí, Goiás, Brazil, and taken to the Seed Laboratory of the Federal Institute Goiano, Rio Verde Campus, where they were processed and the seeds were extracted. To establish the predetermined water content (43%, 37%, 34%, 31%, and 28% wet basis), seeds with an initial water content of 43% were kept in an oven with forced air circulation at a temperature of 40 °C until they reached the predetermined water content levels. Next, the seeds were placed in acrylic holders with double-sided tape and transported to the Federal University of Lavras (UFLA), where they were exposed to different intensities of radiation. The X-ray test was conducted with 200 seeds per treatment, and images of the internal structures of the seeds were evaluated. The seeds were returned to the Seed Laboratory of the Federal Institute Goiano, Rio Verde Campus, where the germination test was initiated. The experimental design was completely randomized, in a factorial design (5 × 4), in which there were five water content levels and four seed classes, with four replications. The X-ray test was efficient in the identification of filled, malformed, damaged and empty seeds, which germination rate above 50% in the filled seeds. This visualization of the internal morphology of the seed can be useful to select seeds of better quality, improving the percentage of germination of C. pubescens seeds.


Resumo O objetivo deste trabalho foi avaliar a morfologia interna de sementes de Campomanesia pubescens (Mart. ex DC.) O.Berg com diferentes teores de água por meio de análise de imagens de raios-X, e correlacionar as imagens com a germinação dessas sementes. Os frutos foram coletados no município de Jataí, Goiás, Brasil, e levados ao Laboratório de Sementes do Instituto Federal Goiano, Campus Rio Verde, onde foram processados ​​e as sementes foram extraídas. Para estabelecer o teor de água predeterminado (43%, 37%, 34%, 31% e 28% base úmida), as sementes com um teor inicial de água de 43% foram mantidas em estufa com circulação de ar induzida, a uma temperatura de 40 °C até atingirem os níveis de conteúdo de água predeterminados. Em seguida, as sementes foram colocadas em suportes acrílicos com fita dupla face e transportadas para a Universidade Federal de Lavras (UFLA), onde foram expostas a diferentes intensidades de radiação. O teste de raios-X foi realizado com 200 sementes por tratamento, e imagens das estruturas internas das sementes foram avaliadas. As sementes foram devolvidas ao Laboratório de Sementes do Instituto Federal Goiano, Campus Rio Verde, onde foi iniciado o teste de germinação. O delineamento experimental foi inteiramente casualizado, em esquema fatorial (5 × 4), no qual foram encontrados cinco níveis de umidade e quatro classes de sementes, com quatro repetições. O teste de raios-X foi eficiente na identificação de sementes preenchidas, malformadas, danificadas e vazias, com taxas de germinação acima dos 50% nas sementes cheias. Essa visualização das morfologia interna da semente pode ser útil para selecionar sementes de melhor qualidade, melhorando a porcentagem de germinação das sementes de C. pubescens.


Asunto(s)
Germinación , Myrtaceae , Semillas , Temperatura , Brasil , Desecación
2.
Braz. j. biol ; Braz. j. biol;2017.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467356

RESUMEN

Abstract The objective of this study was to evaluate the internal morphology of seeds of Campomanesia pubescens (Mart. ex DC.) O. Berg with varying water content through X-ray image analysis, and correlate the images with the germination of these seeds. Fruits were collected in Jataí, Goiás, Brazil, and taken to the Seed Laboratory of the Federal Institute Goiano, Rio Verde Campus, where they were processed and the seeds were extracted. To establish the predetermined water content (43%, 37%, 34%, 31%, and 28% wet basis), seeds with an initial water content of 43% were kept in an oven with forced air circulation at a temperature of 40 °C until they reached the predetermined water content levels. Next, the seeds were placed in acrylic holders with double-sided tape and transported to the Federal University of Lavras (UFLA), where they were exposed to different intensities of radiation. The X-ray test was conducted with 200 seeds per treatment, and images of the internal structures of the seeds were evaluated. The seeds were returned to the Seed Laboratory of the Federal Institute Goiano, Rio Verde Campus, where the germination test was initiated. The experimental design was completely randomized, in a factorial design (5 × 4), in which there were five water content levels and four seed classes, with four replications. The X-ray test was efficient in the identification of filled, malformed, damaged and empty seeds, which germination rate above 50% in the filled seeds. This visualization of the internal morphology of the seed can be useful to select seeds of better quality, improving the percentage of germination of C. pubescens seeds.


Resumo O objetivo deste trabalho foi avaliar a morfologia interna de sementes de Campomanesia pubescens (Mart. ex DC.) O.Berg com diferentes teores de água por meio de análise de imagens de raios-X, e correlacionar as imagens com a germinação dessas sementes. Os frutos foram coletados no município de Jataí, Goiás, Brasil, e levados ao Laboratório de Sementes do Instituto Federal Goiano, Campus Rio Verde, onde foram processados e as sementes foram extraídas. Para estabelecer o teor de água predeterminado (43%, 37%, 34%, 31% e 28% base úmida), as sementes com um teor inicial de água de 43% foram mantidas em estufa com circulação de ar induzida, a uma temperatura de 40 °C até atingirem os níveis de conteúdo de água predeterminados. Em seguida, as sementes foram colocadas em suportes acrílicos com fita dupla face e transportadas para a Universidade Federal de Lavras (UFLA), onde foram expostas a diferentes intensidades de radiação. O teste de raios-X foi realizado com 200 sementes por tratamento, e imagens das estruturas internas das sementes foram avaliadas. As sementes foram devolvidas ao Laboratório de Sementes do Instituto Federal Goiano, Campus Rio Verde, onde foi iniciado o teste de germinação. O delineamento experimental foi inteiramente casualizado, em esquema fatorial (5 × 4), no qual foram encontrados cinco níveis de umidade e quatro classes de sementes, com quatro repetições. O teste de raios-X foi eficiente na identificação de sementes preenchidas, malformadas, danificadas e vazias, com taxas de germinação acima dos 50% nas sementes cheias. Essa visualização das morfologia interna da semente pode ser útil para selecionar sementes de melhor qualidade, melhorando a porcentagem de germinação das sementes de C. pubescens.

3.
J Cell Physiol ; 227(6): 2694-709, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21898410

RESUMEN

This study aimed at investigating the expression and function of uracil nucleotide-sensitive receptors (P2Y(2), P2Y(4), and P2Y(6)) on osteogenic differentiation of human bone marrow stromal cells (BMSCs) in culture. Bone marrow specimens were obtained from postmenopausal female patients (68 ± 5 years old, n = 18) undergoing total hip arthroplasty. UTP and UDP (100 µM) facilitated osteogenic differentiation of the cells measured as increases in alkaline phosphatase (ALP) activity, without affecting cell proliferation. Uracil nucleotides concentration-dependently increased [Ca(2+)](i) in BMSCs; their effects became less evident with time (7 > 21 days) of the cells in culture. Selective activation of P2Y(6) receptors with the stable UDP analog, PSB 0474, mimicked the effects of both UTP and UDP, whereas UTPγS was devoid of effect. Selective blockade of P2Y(6) receptors with MRS 2578 prevented [Ca(2+)](i) rises and osteogenic differentiation caused by UDP at all culture time points. BMSCs are immunoreactive against P2Y(2), P2Y(4), and P2Y(6) receptors. While the expression of P2Y(6) receptors remained fairly constant (7∼21 days), P2Y(2) and P2Y(4) became evident only in less proliferative and more differentiated cultures (7 < 21 days). The rate of extracellular UTP and UDP inactivation was higher in less proliferative and more differentiated cell populations. Immunoreactivity against NTPDase1, -2, and -3 rises as cells differentiate (7 < 21 days). Data show that uracil nucleotides are important regulators of osteogenic cells differentiation predominantly through the activation of UDP-sensitive P2Y(6) receptors coupled to increases in [Ca(2+)](i) . Endogenous actions of uracil nucleotides may be balanced through specific NTPDases determining whether osteoblast progenitors are driven into proliferation or differentiation.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Células de la Médula Ósea/enzimología , Osteogénesis , Posmenopausia/metabolismo , Receptores Purinérgicos P2/metabolismo , Células del Estroma/enzimología , Uridina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Adolescente , Adulto , Anciano , Fosfatasa Alcalina/metabolismo , Antígenos CD/metabolismo , Apirasa/metabolismo , Células de la Médula Ósea/efectos de los fármacos , Calcio/metabolismo , Señalización del Calcio , Proliferación Celular , Células Cultivadas , Cromatografía Líquida de Alta Presión , Femenino , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Humanos , Persona de Mediana Edad , Osteogénesis/efectos de los fármacos , Fenotipo , Agonistas del Receptor Purinérgico P2Y/farmacología , Antagonistas del Receptor Purinérgico P2Y/farmacología , Receptores Purinérgicos P2/efectos de los fármacos , Receptores Purinérgicos P2Y2/metabolismo , Células del Estroma/efectos de los fármacos , Factores de Tiempo , Uridina Trifosfato/metabolismo , Adulto Joven
4.
J Cell Physiol ; 226(5): 1353-66, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20945394

RESUMEN

Purines are important modulators of bone cell biology. ATP is metabolized into adenosine by human primary osteoblast cells (HPOC); due to very low activity of adenosine deaminase, the nucleoside is the end product of the ecto-nucleotidase cascade. We, therefore, investigated the expression and function of adenosine receptor subtypes (A(1) , A(2A) , A(2B) , and A(3) ) during proliferation and osteogenic differentiation of HPOC. Adenosine A(1) (CPA), A(2A) (CGS21680C), A(2B) (NECA), and A(3) (2-Cl-IB-MECA) receptor agonists concentration-dependently increased HPOC proliferation. Agonist-induced HPOC proliferation was prevented by their selective antagonists, DPCPX, SCH442416, PSB603, and MRS1191. CPA and NECA facilitated osteogenic differentiation measured by increases in alkaline phosphatase (ALP) activity. This contrasts with the effect of CGS21680C which delayed HPOC differentiation; 2-Cl-IB-MECA was devoid of effect. Blockade of the A(2B) receptor with PSB603 prevented osteogenic differentiation by NECA. In the presence of the A(1) antagonist, DPCPX, CPA reduced ALP activity at 21 and 28 days in culture. At the same time points, blockade of A(2A) receptors with SCH442416 transformed the inhibitory effect of CGS21680C into facilitation. Inhibition of adenosine uptake with dipyridamole caused a net increase in osteogenic differentiation. The presence of all subtypes of adenosine receptors on HPOC was confirmed by immunocytochemistry. Data show that adenosine is an important regulator of osteogenic cell differentiation through the activation of subtype-specific receptors. The most abundant A(2B) receptor seems to have a consistent role in cell differentiation, which may be balanced through the relative strengths of A(1) or A(2A) receptors determining whether osteoblasts are driven into proliferation or differentiation.


Asunto(s)
Adenosina/metabolismo , Células de la Médula Ósea/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Agonistas del Receptor Purinérgico P1/farmacología , Receptores Purinérgicos P1/efectos de los fármacos , Células del Estroma/efectos de los fármacos , Adenosina Monofosfato/metabolismo , Adenosina Trifosfato/metabolismo , Anciano , Fosfatasa Alcalina/metabolismo , Biomarcadores/metabolismo , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/patología , Células Cultivadas , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Osteoblastos/metabolismo , Osteoblastos/patología , Antagonistas de Receptores Purinérgicos P1/farmacología , Receptores Purinérgicos P1/metabolismo , Células del Estroma/metabolismo , Células del Estroma/patología , Factores de Tiempo
5.
J Clin Epidemiol ; 50(12): 1377-84, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9449941

RESUMEN

A project for studying the prevalence of hereditary ataxias (HA) and familial spastic paraplegias (FSP) in Portugal was set up in 1993. The ascertainment of patients in previous prevalence studies relied mainly on the information of hospital admissions and out-patient contacts with the neurology and other related departments at central hospitals covering the whole region surveyed. Many patients might be overlooked if large populations were studied using this method, since registers at central hospitals are very incomplete and for most part not yet computerized. On the other hand HA and FSP are rare diseases appearing in family clusters, and it would be unreasonable to undertake a sample survey based upon a suitable frame of the Portuguese population. Therefore we decided to carry out a two-phase prevalence survey at district level, involving the collaboration of all physicians working in the district health institutions and the population, in the screening of eligible subjects in phase 1. All subjects screened as positive were examined by a neurologist in phase 2. This method provided a direct estimate of false positives and false negatives were all patients also examined in phase 2, who came to our knowledge using other sources of information. The prevalence of hereditary ataxias and spastic paraplegias in the pilot district was 6.4 per 100,000 inhabitants. The sensitivity of the screening procedure was 81.2% and the predictive value of a positive screening was 25%. Considering the geographically circumscribed district nature of the populations to be studied, the comprehensive sources of case identification used and the high adherence of the health professionals involved, we believe that this method can be widely used, particularly in countries with similar health care services.


Asunto(s)
Paraplejía Espástica Hereditaria/epidemiología , Degeneraciones Espinocerebelosas/epidemiología , Adulto , Interpretación Estadística de Datos , Errores Diagnósticos , Estudios de Factibilidad , Femenino , Registros de Hospitales , Humanos , Masculino , Tamizaje Masivo , Proyectos Piloto , Vigilancia de la Población , Portugal/epidemiología , Valor Predictivo de las Pruebas , Prevalencia , Paraplejía Espástica Hereditaria/diagnóstico , Paraplejía Espástica Hereditaria/genética , Degeneraciones Espinocerebelosas/diagnóstico , Degeneraciones Espinocerebelosas/genética
6.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;24(10): 1011-6, 1991. ilus, tab
Artículo en Inglés | LILACS | ID: lil-102081

RESUMEN

Wuchereria bancrofti microfilariae were isolated from blood of infected individuals and cultured in vitro under several conditions. RPMI 1640 and TC-199 media supplemented with fetal or human serum were able to support the microfilariae for periods up to 35 days at 37-C (viability > 85%). In contrast, in minimal essential medium the microfilariae did not survive for more than 48h. In culture kept at 28-C, where viability was much lower (approximately 10% on day 15), microfilariae differentiated into type IV larvae ("sausage form). The in vitro maintainance of microfilarial larval forms is particularly important in the case of W. bancrofti due to the absence of an experimental model for the disease


Asunto(s)
Humanos , Diferenciación Celular , Técnicas In Vitro , Wuchereria bancrofti/fisiología , Supervivencia Celular , Medios de Cultivo , Temperatura , Wuchereria bancrofti/aislamiento & purificación
7.
Chirurgie ; 116(1): 65-70; discussion 70-1, 1990.
Artículo en Francés | MEDLINE | ID: mdl-2226041

RESUMEN

Emergency surgery is aimed at achieving the same results as elective surgery, but still has specific limitations in the case of CDDC, in spite of significant progress. We describe the physiopathological bases of the emergent treatment of the septic, occlusive and hemorrhagic complications of the CDDC, as well as the experience acquired in the Emergency Unit and Department 3 Hospital San José with 54 cases operated since 1981. The modern means of intensive care and preparation, including powerful antibiotics, make primary resection (1) as a principle possible, but do not allow yielding to the temptation of immediately creating an anastomosis as long as the local conditions have not improved. On the other hand, we emphasize the advantages of performing primary resection-anastomosis surgery in elective operations for non-emergent cases.


Asunto(s)
Divertículo del Colon/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades del Colon/etiología , Enfermedades del Colon/cirugía , Divertículo del Colon/complicaciones , Urgencias Médicas , Femenino , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/cirugía , Humanos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Masculino , Persona de Mediana Edad , Peritonitis/etiología , Peritonitis/cirugía
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