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1.
Plant Biol (Stuttg) ; 24(2): 240-248, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34741381

RESUMO

Approximately 20,000 species of flowering plant offer mainly pollen to their pollinators, generally bees. Stamen dimorphism, a floral trait commonly present in some pollen flowers, is thought to be associated with exclusive pollen provision for highly effective bee pollinators. Notwithstanding, little is known about how stamen dimorphism is related to other floral morphological traits and, consequently, plant-pollinator interactions at the community scale. Here we investigated the relationship between stamen dimorphism and other floral morphological traits, as well as the interactions with pollinators in plants of Melastomataceae. We characterized each plant species as stamen dimorphic or stamen isomorphic according to differences in size and shape between stamen sets. Data on interactions between the plants and their bee pollinators were analysed as quantitative bipartite networks. We found that petal and style size and shape were correlated to stamen dimorphism. Stamen dimorphic species present larger flowers and less variable style shapes than stamen isomorphic species. Furthermore, stamen dimorphism is associated with higher richness of visiting bees, i.e. higher ecological generalization. During the evolutionary history of Melastomataceae, the dependence on pollinators for fruit set has possibly favoured the evolution of larger flowers with dimorphic stamens, which in turn are able to make use of a larger spectrum of pollen-collecting bees, leading to ecological generalization.


Assuntos
Flores/anatomia & histologia , Melastomataceae , Polinização , Animais , Abelhas , Pólen
2.
Acta Ortop Mex ; 35(2): 153-157, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-34731915

RESUMO

INTRODUCTION: The diagnosis of ACL injury is established with the physical examination that includes the Lachman maneuver and the pivot-shift test since it has the highest positive predictive value. Imaging tests such as MRI are still used for confirmation of the same; so the quantification of clinical maneuvers is sought. MATERIAL AND METHODS: Prospective clinical study in which the maneuvers of pivot-shift and Lachman are quantified for later classification. RESULTS: Of 36 patients, 64% found a range between 0 and 3 mm when subtracting the value of the affected knee from the value of the healthy knee. It was found that 28% of the patients recorded values of KT-1000 ranging between 4 and 6 mm of displacement. In 8% of the total patients, values of KT-1000 were found that exceeded 7 mm of displacement. The data obtained are normalized and classified into 3 degrees of injury: grade 1 with partial injury; grade 2 with complete anteromedial and partial injury in posterolateral bundle; grade 3 with complete injury of both bundles. CONCLUSION: A classification is proposed for the degrees of ACL injury with future application to a more personalized reconstruction.


INTRODUCCIÓN: El diagnóstico de lesión del ligamento cruzado anterior se establece con la exploración física que incluya la maniobra de Lachman y la prueba de pivot-shift, ya que cuenta con el mayor valor predictivo positivo. Aún se recurre a pruebas de gabinete como la RMN para la confirmación del mismo; por lo que se busca la cuantificación de maniobras clínicas. MATERIAL Y MÉTODOS: Estudio clínico prospectivo en el que se cuantifican las maniobras de pivot-Shift y Lachman para su posterior clasificación. RESULTADOS: De 36 pacientes, 64% se encontró un rango entre 0 y 3 mm al restar al valor de la rodilla sana el valor de la rodilla afectada. Se encontró que 28% de los pacientes, registraron valores de KT-1000, que oscilan entre los 4 y 6 mm de desplazamiento. En 8% del total de los pacientes se encontraron valores de KT-1000 que superaron los 7 mm de desplazamiento. Se normalizan los datos obtenidos y se clasifican en 3 grados de lesión: grado 1 con lesión parcial; grado 2 con lesión completa de haz anteromedial y parcial en haz posterolateral; grado 3 con lesión completa de ambos haces. CONCLUSIONES: Se propone una clasificación para los grados de lesión del LCA con futura aplicación a una reconstrucción más personalizada.


Assuntos
Lesões do Ligamento Cruzado Anterior , Instabilidade Articular , Ligamento Cruzado Anterior , Lesões do Ligamento Cruzado Anterior/diagnóstico por imagem , Humanos , Instabilidade Articular/diagnóstico por imagem , Articulação do Joelho , Estudos Prospectivos , Amplitude de Movimento Articular
3.
Acta ortop. mex ; 35(2): 153-157, mar.-abr. 2021. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1374161

RESUMO

Resumen: Introducción: El diagnóstico de lesión del ligamento cruzado anterior se establece con la exploración física que incluya la maniobra de Lachman y la prueba de pivot-shift, ya que cuenta con el mayor valor predictivo positivo. Aún se recurre a pruebas de gabinete como la RMN para la confirmación del mismo; por lo que se busca la cuantificación de maniobras clínicas. Material y métodos: Estudio clínico prospectivo en el que se cuantifican las maniobras de pivot-Shift y Lachman para su posterior clasificación. Resultados: De 36 pacientes, 64% se encontró un rango entre 0 y 3 mm al restar al valor de la rodilla sana el valor de la rodilla afectada. Se encontró que 28% de los pacientes, registraron valores de KT-1000, que oscilan entre los 4 y 6 mm de desplazamiento. En 8% del total de los pacientes se encontraron valores de KT-1000 que superaron los 7 mm de desplazamiento. Se normalizan los datos obtenidos y se clasifican en 3 grados de lesión: grado 1 con lesión parcial; grado 2 con lesión completa de haz anteromedial y parcial en haz posterolateral; grado 3 con lesión completa de ambos haces. Conclusiones: Se propone una clasificación para los grados de lesión del LCA con futura aplicación a una reconstrucción más personalizada.


Abstract: Introduction: The diagnosis of ACL injury is established with the physical examination that includes the Lachman maneuver and the pivot-shift test since it has the highest positive predictive value. Imaging tests such as MRI are still used for confirmation of the same; so the quantification of clinical maneuvers is sought. Material and methods: Prospective clinical study in which the maneuvers of pivot-shift and Lachman are quantified for later classification. Results: Of 36 patients, 64% found a range between 0 and 3 mm when subtracting the value of the affected knee from the value of the healthy knee. It was found that 28% of the patients recorded values of KT-1000 ranging between 4 and 6 mm of displacement. In 8% of the total patients, values of KT-1000 were found that exceeded 7 mm of displacement. The data obtained are normalized and classified into 3 degrees of injury: grade 1 with partial injury; grade 2 with complete anteromedial and partial injury in posterolateral bundle; grade 3 with complete injury of both bundles. Conclusion: A classification is proposed for the degrees of ACL injury with future application to a more personalized reconstruction.

4.
Plant Biol (Stuttg) ; 23(4): 556-563, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33550673

RESUMO

Floral structures, such as stamen appendages, play crucial roles in pollinator attraction, pollen release dynamics and, ultimately, the reproductive success of plants. The pollen-rewarding, bee buzz-pollinated flowers of Melastomataceae often bear conspicuous staminal appendages. Surprisingly, their functional role in the pollination process remains largely unclear. We use Huberia bradeana Bochorny & R. Goldenb. (Melastomataceae) with conspicuously elongated, twisted stamen appendages to investigate their functional role in the pollination process. We studied the effect of stamen appendages on pollinator behaviour and reproductive success by comparing manipulated flowers (appendages removed) with unmanipulated flowers. To assess bee pollinator behaviour, we measured three properties of buzzes (vibrations) produced by bees on Huberia flowers: frequency, duration and number of buzzes per flower visit. We measured male and female reproductive success by monitoring pollen release and deposition after single bee visits. Finally, we used artificial vibrations and laser vibrometry to assess how flower vibrational properties change with the removal of stamen appendages. Our results show that the absence of staminal appendages does not modify bee buzzing behaviour. Pollen release was higher in unmanipulated flowers, but stigmatic pollen loads differ only marginally between the two treatments. We also detected lower vibration amplitudes in intact flowers as compared to manipulated flowers in artificial vibration experiments. The presence of connective appendages are crucial in transmitting vibrations and assuring optimal pollen release. Therefore, we propose that the high diversity of colours, shapes and sizes of connective appendages in buzz-pollinated flowers may have evolved by selection through male fitness.


Assuntos
Melastomataceae , Polinização , Animais , Abelhas , Flores , Pólen , Reprodução
5.
Acta ortop. mex ; 33(6): 370-375, nov.-dic. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1345063

RESUMO

Resumen: Introducción: Las lesiones del LCA se encuentran dentro de las lesiones ligamentarias más frecuentes. Esto ha llevado al desarrollo de diferentes técnicas quirúrgicas para recuperar la estabilidad de la rodilla. Material y métodos: Estudio clínico, aleatorizado, ciego comparando técnicas de reconstrucción de LCA con Un Haz y «U-Dos¼ mediante escalas clínicas y artrometría con KT-1000 y Pivot Shift Meter. Resultados: De 36 pacientes, 52.94% fue sorteado para la técnica de Un Haz y 47.06% para «U-Dos¼. En 11.76% de los pacientes se presentó un desplazamiento mayor a 11 mm en la rodilla afectada con KT-1000. En 8.82% se mostró un desplazamiento anterior igual en ambas rodillas. Un paciente presentó un desplazamiento anterior mayor posterior a la cirugía de reconstrucción con la técnica de Un Haz, pero con mejoría en las escalas clínicas. En las mediciones de Pivot Shift se encontró una diferencia en el desplazamiento mayor a los 4,000 m/s en el eje de las X tras la técnica de Un Haz en comparación con la rodilla sana calculando integrales, mientras que con U-Dos la diferencia fue menor de 600 m/s. En el eje de «Y¼ se encontró una diferencia > 3,500 m/s entre la pierna sana y la lesionada, la cual disminuye a menos de 2,000 m/s tras la reconstrucción mediante técnica de U-Dos. Conclusiones: A lo largo del estudio se han encontrado diferencias en la evolución de los pacientes que indican que la reparación mediante la técnica de U-Dos tiene mejores resultados al lograr recuperar la estabilidad anteroposterior y rotacional del miembro afectado.


Abstract: Introduction: ACL injuries are found within the most common ligament injuries. This has led to the development of different surgical techniques to restore knee stability. Material y Methods: Clinical study, randomized, blind comparing ACL reconstruction techniques with One Band and «U-Two¼ using clinical scales and arthrometria with KT-1000 and Pivot Shift Meter. Results: Of 36 patients, 52.94% was drawn for the One Band technique and 47.06% for «U-Two¼. 11.76% of patients had a displacement greater than 11mm in the affected knee with KT-1000. 8.82% showed an equal anterior displacement on both knees. One patient had a major previous displacement after reconstruction surgery with the one band technique, but with improvement on clinical scales. Pivot Shift measurements found a difference in displacement greater than 4,000 m/s on the X axis following the One Band technique compared to the healthy knee calculating integrals, while with U-Two the difference was less than 600 m/s. On the Y axis a difference of > 3,500 m/s was found between the healthy and the injured leg, which decreases to less than 2,000 m/s after reconstruction using U-Two technique. Conclusions: Differences have been found throughout the study in patient evolution, indicating that repair using the U-Dos technique has better results in recovering the anteroposterior and rotational stability of the affected limb.


Assuntos
Humanos , Reconstrução do Ligamento Cruzado Anterior , Lesões do Ligamento Cruzado Anterior/cirurgia , Instabilidade Articular/cirurgia , Fenômenos Biomecânicos , Amplitude de Movimento Articular , Articulação do Joelho/cirurgia
6.
J Atr Fibrillation ; 11(6): 2147, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31384365

RESUMO

AIMS: Pulmonary vein isolation (PVI) can be accomplished using radiofrequency (RF) or second generation cryoballoon (CB2). We aimed to compare the freedom from very late recurrence (VLR) defined as recurrence beyond one year in patients who were AF-free during the first post-procedural year after PVI using CB2 or RF. METHODS: Consecutive patients who underwent PVI by RF or CB2 ablation between August 2014 and December 2015 were included. The primary endpoint was the occurrence of VLR in follow-up after 12 months. Patients who experienced recurrence between the first 3 to 12 months after PVI and those who did not complete 15-month follow-up time were excluded. RESULTS: 139 patients were included: 68 underwent PVI by CB2 and 71 using RF. The global VLR rate was of 22.15%. The freedom from VLR beyond 12-month follow-up was of 84.5% (57 patients) for the CB2 group vs. 71% (50 patients) in the RF group (p=0.037). 15 patients underwent re-ablation (11 of the RF group and 4 of the CB2 group): all of the patients who had undergone PVI by RF in the index procedure were found to have vein reconnection, whereas none of the CB2 group had reconnected veins (3 cavotricuspid isthmus and 1 mitral isthmus). CONCLUSION: In patients free of recurrence during the first post-procedural year after pulmonary vein isolation for the treatment of paroxysmal atrial fibrillation: second generation cryoballoon ablation showed a significantly lower very late recurrence rate compared to radiofrequency ablation. CONDENSED ABSTRACT: The present study evaluates the freedom from very late recurrence (VLR), defined as recurrence in patients who were arrhythmia-free during the first post-procedural year after pulmonary vein isolation using second generation cryoballoon (CB2) or radiofrequency (RF). CB2 ablation had a lower VLR rate compared to RF.

7.
Acta Ortop Mex ; 33(6): 370-375, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-32767879

RESUMO

INTRODUCTION: ACL injuries are found within the most common ligament injuries. This has led to the development of different surgical techniques to restore knee stability. MATERIAL Y METHODS: Clinical study, randomized, blind comparing ACL reconstruction techniques with One Band and «U-Two¼ using clinical scales and arthrometria with KT-1000 and Pivot Shift Meter. RESULTS: Of 36 patients, 52.94% was drawn for the One Band technique and 47.06% for «U-Two¼. 11.76% of patients had a displacement greater than 11mm in the affected knee with KT-1000. 8.82% showed an equal anterior displacement on both knees. One patient had a major previous displacement after reconstruction surgery with the one band technique, but with improvement on clinical scales. Pivot Shift measurements found a difference in displacement greater than 4,000 m/s on the X axis following the One Band technique compared to the healthy knee calculating integrals, while with U-Two the difference was less than 600 m/s. On the Y axis a difference of 3,500 m/s was found between the healthy and the injured leg, which decreases to less than 2,000 m/s after reconstruction using U-Two technique. CONCLUSIONS: Differences have been found throughout the study in patient evolution, indicating that repair using the U-Dos technique has better results in recovering the anteroposterior and rotational stability of the affected limb.


INTRODUCCIÓN: Las lesiones del LCA se encuentran dentro de las lesiones ligamentarias más frecuentes. Esto ha llevado al desarrollo de diferentes técnicas quirúrgicas para recuperar la estabilidad de la rodilla. MATERIAL Y MÉTODOS: Estudio clínico, aleatorizado, ciego comparando técnicas de reconstrucción de LCA con Un Haz y «U-Dos¼ mediante escalas clínicas y artrometría con KT-1000 y Pivot Shift Meter. RESULTADOS: De 36 pacientes, 52.94% fue sorteado para la técnica de Un Haz y 47.06% para «U-Dos¼. En 11.76% de los pacientes se presentó un desplazamiento mayor a 11 mm en la rodilla afectada con KT-1000. En 8.82% se mostró un desplazamiento anterior igual en ambas rodillas. Un paciente presentó un desplazamiento anterior mayor posterior a la cirugía de reconstrucción con la técnica de Un Haz, pero con mejoría en las escalas clínicas. En las mediciones de Pivot Shift se encontró una diferencia en el desplazamiento mayor a los 4,000 m/s en el eje de las X tras la técnica de Un Haz en comparación con la rodilla sana calculando integrales, mientras que con U-Dos la diferencia fue menor de 600 m/s. En el eje de «Y¼ se encontró una diferencia 3,500 m/s entre la pierna sana y la lesionada, la cual disminuye a menos de 2,000 m/s tras la reconstrucción mediante técnica de U-Dos. CONCLUSIONES: A lo largo del estudio se han encontrado diferencias en la evolución de los pacientes que indican que la reparación mediante la técnica de U-Dos tiene mejores resultados al lograr recuperar la estabilidad anteroposterior y rotacional del miembro afectado.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior , Instabilidade Articular/cirurgia , Fenômenos Biomecânicos , Humanos , Articulação do Joelho/cirurgia , Amplitude de Movimento Articular
8.
Hum Reprod ; 33(5): 914-918, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29538680

RESUMO

Testotoxicosis is a rare cause of peripheral precocious puberty in boys caused by constitutively activating mutations of the LHCG receptor. Affected males usually have normal gonadotropin profiles and fertility in their adult life. Here, we described the long-term follow-up of a 24-year-old young man with severe testotoxicosis due to a de novo activating mutation in the third transmembrane helix of the LHCGR (p.Leu457Arg). This patient was treated with different medications, including medroxyprogesterone acetate, ketoconazole, cyproterone acetate and aromatase inhibitor from age 2.5 to 9.5 years. His basal and GnRH-stimulated gonadotropin levels were continually suppressed during and after medical treatment. At adulthood, extremely high serum testosterone levels (>35 nmol/L), undetectable gonadotropin levels (LH < 0.15 IU/L and FSH < 0.6 IU/L) and oligozoospermia were evidenced. Despite his suppressed FSH levels and an unfavorable spermogram, the patient fathered a healthy girl and biological paternity was confirmed through analysis of microsatellites. Spontaneous fertility in a young man with severe testotoxicosis and chronic suppression of FSH levels reinforces the key role of high intratesticular testosterone levels in human spermatogenesis.


Assuntos
Fertilidade/genética , Puberdade Precoce/genética , Receptores do LH/genética , Testosterona/sangue , Adulto , Humanos , Masculino , Mutação , Puberdade Precoce/sangue
9.
Rev. chil. obstet. ginecol. (En línea) ; 83(1): 45-51, feb. 2018. tab
Artigo em Espanhol | LILACS | ID: biblio-899971

RESUMO

RESUMEN Objetivo: Determinar la influencia de la actividad física en la sintomatología del síndrome premenstrual en un grupo de mujeres de la Facultad de Medicina de la Universidad de Concepción. Métodos: Estudio observacional, descriptivo, transversal, realizado en 340 mujeres escogidas al azar de edades entre 18 a 27 años, estudiantes de la Facultad de Medicina de la Universidad de Concepción. Se utilizaron instrumentos validados para población chilena, como los criterios para el diagnóstico del trastorno disfórico premenstrual DSM-IV-TR, la Escala Visual Análoga (EVA) para la medición del dolor y el Cuestionario Internacional de Actividad Física (IPAQ) para la intensidad de esta. Los datos se obtuvieron por medio de encuestas autoadministradas y los resultados se analizaron mediante pruebas estadísticas. Resultados: Un 55,9% (n=190) presenta Síndrome premenstrual según los criterios utilizados. Los principales síntomas manifestados fueron: fatiga y falta de energía en un 64,7% (n=220), hipersensibilidad mamaria, cefalea e hinchazón en un 62,9% (n=214) y ansiedad, tensión, agobio y colapso en un 60,9% (n=207). Del total de encuestadas, el mayor porcentaje (42,6%) (n=145) realiza actividad física moderada. Al cruzar las variables de actividad física y la sintomatología del síndrome premenstrual se estableció que no existía relación entre ellas (valor p=0,605). Conclusiones: la actividad física no tiene influencia sobre la disminución de la sintomatología del síndrome premenstrual en la población estudiada.


ABSTRACT Objectives: Determine the influence of physical activity on the symptoms of premenstrual syndrome in females students of the Faculty of Medicine, Universidad de Concepción, Concepción Campus in 2014 Methods: A cross sectional study was applied to 340 randomly selected women aged between 18-27 years old belonging to the Faculty of Medicine of the Universidad de Concepción. Data were obtained through self-administered surveys and the results were analyzed by the respective statistical techniques. Results: Of the sample (n = 340), 55.9% (n = 190) had premenstrual syndrome according to the canon used. The main symptoms manifested were fatigue and lack of energy in 64.7% (n = 220), breast tenderness, headache and swelling in 62.9% (n = 214) and anxiety, stress, overwhelm and collapse into a 60.9% (n = 207). Of the total of the participants, the highest percentage (42.6%) (n = 145) performs moderate physical activity. When the variables of physical activity and premenstrual syndrome were crossed, was established that it did not exist relationship between them (p value = 0.605). Conclusions: With the obtaining and analyzing of the results, it seems that physical activity does not have major influence on the symptoms of premenstrual syndrome in the population studied.


Assuntos
Humanos , Feminino , Adolescente , Adulto , Síndrome Pré-Menstrual/prevenção & controle , Síndrome Pré-Menstrual/psicologia , Exercício Físico/psicologia , Qualidade de Vida , Estudantes de Medicina , Inquéritos e Questionários , Estudo Observacional
10.
Scand J Med Sci Sports ; 28(2): 425-435, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28649743

RESUMO

We investigated the skeletal muscle adaptation to l-arginine supplementation prior to a single session of resistance exercise (RE) during the early phase of muscle repair. Wistar rats were randomly assigned into non-exercised (Control), RE plus vehicle (RE); RE plus l-arginine (RE+L-arg) and RE plus aminoguanidine (RE+AG) groups. Animals received four doses of either vehicle (0.9% NaCl), l-arg (1 g/b.w.), or AG (iNOS inhibitor) (50 mg/b.w.). The animals performed a single RE session until the concentric failure (ladder climbing; 80% overload) and the skeletal muscles were harvested at 0, 8, 24, and 48 hours post-RE. The RE resulted in increased neutrophil infiltrate (24 hours post-RE) (3621 vs 11852; P<.0001) associated with enhanced TNF-α (819.49 vs 357.02; P<.005) and IL-6 (3.84 vs 1.08; P<.0001). Prior, l-arginine supplementation attenuates neutrophil infiltration (5622; P<.0001), and also TNF-α (506.01; P<.05) and IL-6 (2.51, P<.05) levels. AG pretreatment mediated an inhibition of iNOS levels similar to levels found in RE group. RE animals displayed increased of atrogin-1 (1.9 fold) and MuRF-1 (3.2 fold) mRNA levels, reversed by l-arg supplementation [atrogin-1 (0.6 fold; P<.001); MuRF-1 (0.8-fold; P<.001)] at 24 hours post-RE. MyoD up-regulated levels were restricted to l-arg treated animals at 24 hours (2.8 vs 1.5 fold; P<.005) and 48 hours post-RE (2.4 vs 1.1 fold; P<.001). AG pretreatment reversed these processes at 24 hours [atrogin-1 (2.1 fold; P<.0001); MuRF-1 (2.5 fold; P<.0001); MyoD (1.4 fold)]. l-arginine supplementation seems to attenuate the resolution of RE-induced muscle inflammation and up-regulates MyoD expression during the early phase of muscle repair.


Assuntos
Arginina/administração & dosagem , Inflamação/metabolismo , Músculo Esquelético/metabolismo , Condicionamento Físico Animal/fisiologia , Adaptação Fisiológica , Animais , Guanidinas/administração & dosagem , Inflamação/genética , Interleucina-6/metabolismo , Masculino , Proteínas Musculares/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Peroxidase/metabolismo , Ratos Wistar , Proteínas Ligases SKP Culina F-Box/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
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