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1.
J Invertebr Pathol ; 202: 108041, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38092085

RESUMEN

The Asian tiger mosquito, Aedes albopictus, is a highly invasive and aggressive species capable of transmitting a large number of etiological agents of medical and veterinary importance, posing a high risk for the transmission of emerging viruses between animals and humans. In this work, we evaluated the mosquitocidal activity of Neochloris aquatica against A. albopictus throughout its development and analyzed whether this effect was potentiated when the microalga was cultivated under stress conditions due to nutrient deprivation. Our results suggest that N. aquatica produces metabolites that have negative effects on these insects, including larval mortality, interruption of pupal development, and incomplete emergence of adults when fed on microalgae in the larval stages. When microalgae were cultured under stress conditions, an increase in molting defects was recorded, and the number of healthy adults emerged drastically decreased. Histological studies revealed severe signs of total disintegration of different tissues and organs in the thorax and abdomen regions. The muscles and fat bodies in the midgut and foregut were severely distorted. In particular, larval intestinal tissue damage included vacuolization of the cytoplasm, destruction of brush border microvilli, and dilation of the intercellular space, which are distinctive morphological characteristics of apoptotic cells. Evidence suggests that N. aquatica produces metabolites with mosquitocidal effects that affect development and, therefore, the ability to vector etiological agents of medical and veterinary importance.


Asunto(s)
Aedes , Chlorophyceae , Microalgas , Humanos , Animales , Larva , Muda
2.
Plant Physiol Biochem ; 197: 107635, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36933508

RESUMEN

The microalgae Neochloris aquatica were previously evaluated as a potential biological control agent and source of bioactive compounds against immature stages of Culex quinquefasciatus. Larvae reared on microalgae suspension showed mortality or drastic effects with morphological alterations and damage in the midgut. N. aquatica have nutritional and toxic effects, resulting in delayed life cycle and incomplete adult development. Given the possibility of its use as a biological control agent, in this work we evaluate the effect of microalgae on other organisms of the environment, such as plants. Arabidopsis thaliana, a terrestrial plant, and Lemna sp., a floating aquatic plant, were selected as examples. Interaction assays and compound evaluations showed that the microalgae release auxins causing root inhibition, smaller epidermal cells and hairy root development. In Lemna sp., a slight decrease in growth rate was observed, with no deleterious effects on the fronds. On the other hand, we detected a detrimental effect on plants when interactions were performed in a closed environment, in a medium containing soluble carbonate, in which microalgae culture rapidly modifies the pH. The experiments showed that alkalinization of the medium inhibits plant growth, causing bleaching of leaves or fronds. This negative effect in plants was not observed when plants and microalgae were cultured in carbonate-free media. In conclusion, the results showed that N. aquatica can modify plant growth without being harmful, but the rapid alkalinization produced by carbon metabolism of microalgae under CO2-limiting conditions, could regulate the number of plants.


Asunto(s)
Arabidopsis , Microalgas , Agentes de Control Biológico/farmacología , Plantas , Hormonas/farmacología
3.
Front Plant Sci ; 13: 992543, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36212340

RESUMEN

Heterotrimeric Nuclear Factor Y (NF-Y) transcription factors are key regulators of the symbiotic program that controls rhizobial infection and nodule organogenesis. Using a yeast two-hybrid screening, we identified a putative protein kinase of Phaseolus vulgaris that interacts with the C subunit of the NF-Y complex. Physical interaction between NF-YC1 Interacting Protein Kinase (NIPK) and NF-YC1 occurs in the cytoplasm and the plasma membrane. Only one of the three canonical amino acids predicted to be required for catalytic activity is conserved in NIPK and its putative homologs from lycophytes to angiosperms, indicating that NIPK is an evolutionary conserved pseudokinase. Post-transcriptional silencing on NIPK affected infection and nodule organogenesis, suggesting NIPK is a positive regulator of the NF-Y transcriptional complex. In addition, NIPK is required for activation of cell cycle genes and early symbiotic genes in response to rhizobia, including NF-YA1 and NF-YC1. However, strain preference in co-inoculation experiments was not affected by NIPK silencing, suggesting that some functions of the NF-Y complex are independent of NIPK. Our work adds a new component associated with the NF-Y transcriptional regulators in the context of nitrogen-fixing symbiosis.

4.
PLoS Negl Trop Dis ; 15(12): e0009988, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34860833

RESUMEN

Culex quinquefasciatus is a cosmopolitan species widely distributed in the tropical and subtropical areas of the world. Due to its long history of close association with humans, the transmission of arboviruses and parasites have an important role in veterinary and public health. Adult females feed mainly on birds although they can also feed on humans and other mammals. On the other hand, larvae are able to feed on a great diversity of microorganisms, including microalgae, present in natural or artificial breeding sites with a high organic load. These two particularities, mentioned above, are some of the reasons why this mosquito is so successful in the environment. In this work, we report the identification of a microalga found during field sampling in artificial breeding sites, in a group of discarded tires with accumulated rainwater. Surprisingly, only one of them had a bright green culture without mosquito larvae while the other surrounding tires contained a large number of mosquito larvae. We isolated and identified this microorganism as Neochloris aquatica, and it was evaluated as a potential biological control agent against Cx. quinquefasciatus. The oviposition site preference in the presence of the alga by gravid females, and the effects on larval development were analyzed. Additionally, microalga effect on Cx. quinquefasciatus wild type, naturally infected with the endosymbiotic bacterium Wolbachia (w+) and Wolbachia free (w-) laboratory lines was explored. According to our results, even though it is chosen by gravid females to lay their eggs, the microalga had a negative effect on the development of larvae from both populations. Additionally, when the larvae were fed with a culture of alga supplemented with balanced fish food used as control diet, they were not able to reverse its effect, and were unable to complete development until adulthood. Here, N. aquatica is described as a biological agent, and as a potential source of bioactive compounds for the control of mosquito populations important in veterinary and human health.


Asunto(s)
Culex/crecimiento & desarrollo , Culex/microbiología , Larva/microbiología , Microalgas , Control de Mosquitos/métodos , Mosquitos Vectores/microbiología , Animales , Culex/fisiología , Conducta Alimentaria , Femenino , Mosquitos Vectores/fisiología , Oviposición , Wolbachia/aislamiento & purificación
5.
Planta ; 253(2): 50, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33506329

RESUMEN

MAIN CONCLUSION: Morpho-physiological changes were observed in Arabidopsis plants acclimated to long-term combined cold and water deficit stresses. Limiting growth and differences in bolting, flowering, and silique development were evidenced. In nature, plants are exposed to multiple and simultaneous abiotic stresses that influence their growth, development, and reproduction. In the last years, the study of combined stresses has aroused the interest to know the physiological and molecular responses, because these new stress conditions are probed to be different from the sum of the individual stress. We are interested in the study of the acclimation of plants growing under the combination of cold and water deficit stresses prevalent in cold-arid or semi-arid climates worldwide. We hypothesized that the reproduction of the acclimated plants will be compromised and affected. Arabidopsis plants were submitted to long-term combined stress from the beginning to the reproductive stage, when floral bud was visible, until the silique development. Our results demonstrate severe morpho-anatomical changes after acclimation to combined stress. Inflorescence stem morphology was altered having a delayed bolting and a limited growth. Flowering and silique formation were delayed, and a higher size in the corolla and the petals was observed. Flower and silique number were severely diminished as a result of combined stress, unlike acclimated plants to individual cold stress. These traits were recovered after deacclimation to optimal conditions and plants achieved similar silique production as control plants. The long-term stress results suggest that there is not a single dominant stress, but there is an alternating dominance depending on the structure or the plant stage development evaluated.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Frío , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Reproducción , Agua
6.
Rev. bras. entomol ; 65(2): e20200115, 2021. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1251248

RESUMEN

Abstract The interest in and use of Aedes (Stegomyia) aegypti (Linnaeus) (Diptera: Culicidae) insectary lines increased in most laboratories around the world since the recognition of the transmission of human and animal pathogens by this mosquito species, resulting in further scientific research on tropical diseases and vectors, and the development of chemical and biological products for mosquito populations control. In recent years, approaches to mosquito populations reduction have focused on new technologies that include the release of Wolbachia-infected lines, genetically modified vector and insects subjected to radiation in the Sterile Insect Technique. In order to evaluate some of these techniques, it is essential to count with wild A. aegypti populations and the reference strain, accurately identified, maintained under laboratory conditions. This work proposes a new tool to monitor possible exchanges between reference mosquito strain and wild native populations of A. aegypti in neighboring areas, or between different lines in the same insectary. We aligned and compared ND5 gene fragments of A. aegypti from diverse sources, finding a region with putative Single Nucleotide Polymorphisms between individuals of Rockefeller (Rock) strain and different wild A. aegypti populations. These polymorphic sites in the molecular marker, allowed us to discriminate Rock reference strain from the wild A. aegypti haplotypes found in the southeast of Argentina and bordering areas with Brazil, Uruguay and Paraguay, and it can be useful as a tool for regulatory entities of mosquito insectaries at different Arthropod Containment Levels.

7.
PLoS One ; 12(9): e0185286, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28945799

RESUMEN

Alkaline/neutral invertases (A/N-Inv), glucosidases that irreversibly hydrolyze sucrose into glucose and fructose, play significant roles in plant growth, development, and stress adaptation. They occur as multiple isoforms located in the cytosol or organelles. In Arabidopsis thaliana, two mitochondrial A/N-Inv genes (A/N-InvA and A/N-InvC) have already been investigated. In this study, we functionally characterized A/N-InvH, a third Arabidopsis gene coding for a mitochondrial-targeted protein. The phenotypic analysis of knockout mutant plants (invh) showed a severely reduced shoot growth, while root development was not affected. The emergence of the first floral bud and the opening of the first flower were the most affected stages, presenting a significant delay. A/N-InvH transcription is markedly active in reproductive tissues. It is also expressed in the elongation and apical meristem root zones. Our results show that A/N-InvH expression is not evident in photosynthetic tissues, despite being of relevance in developmental processes and mitochondrial functional status. NaCl and mannitol treatments increased A/N-InvH expression twofold in the columella root cap. Moreover, the absence of A/N-InvH prevented ROS formation, not only in invh roots of salt- and ABA-treated seedlings but also in invh control roots. We hypothesize that this isoform may take part in the ROS/sugar (sucrose or its hydrolysis products) signaling pathway network, involved in reproductive tissue development, cell elongation, and abiotic stress responses.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , beta-Fructofuranosidasa/metabolismo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Técnicas de Inactivación de Genes , Genes de Plantas , Concentración de Iones de Hidrógeno , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Mitocondrias/enzimología , Proteínas Mitocondriales/química , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Fenotipo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Especies Reactivas de Oxígeno/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Distribución Tisular , beta-Fructofuranosidasa/química , beta-Fructofuranosidasa/genética
8.
World Neurosurg ; 83(4): 588-95, 2015 04.
Artículo en Inglés | MEDLINE | ID: mdl-25527878

RESUMEN

OBJECTIVE: The cause precipitating intracranial aneurysm rupture remains unknown in many cases. It has been observed that aneurysm ruptures are clustered in time, but the trigger mechanism remains obscure. Because solar activity has been associated with cardiovascular mortality and morbidity, we decided to study its association to aneurysm rupture in the Swiss population. METHODS: Patient data were extracted from the Swiss SOS database, at time of analysis covering 918 consecutive patients with angiography-proven aneurysmal subarachnoid hemorrhage treated at 7 Swiss neurovascular centers between January 1, 2009, and December 31, 2011. The daily rupture frequency (RF) was correlated to the absolute amount and the change in various parameters of interest representing continuous measurements of solar activity (radioflux [F10.7 index], solar proton flux, solar flare occurrence, planetary K-index/planetary A-index, Space Environment Services Center [SESC] sunspot number and sunspot area) using Poisson regression analysis. RESULTS: During the period of interest, there were 517 days without recorded aneurysm rupture. There were 398, 139, 27, 12, 1, and 1 days with 1, 2, 3, 4, 5, and 6 ruptures per day. Poisson regression analysis demonstrated a significant correlation of F10.7 index and RF (incidence rate ratio [IRR] = 1.006303; standard error (SE) 0.0013201; 95% confidence interval (CI) 1.003719-1.008894; P < 0.001), according to which every 1-unit increase of the F10.7 index increased the count for an aneurysm to rupture by 0.63%. A likewise statistically significant relationship of both the SESC sunspot number (IRR 1.003413; SE 0.0007913; 95% CI 1.001864-1.004965; P < 0.001) and the sunspot area (IRR 1.000419; SE 0.0000866; 95% CI 1.000249-1.000589; P < 0.001) emerged. All other variables analyzed showed no significant correlation with RF. CONCLUSIONS: We found greater radioflux, SESC sunspot number, and sunspot area to be associated with an increased count of aneurysm rupture. The clinical meaningfulness of this statistical association must be interpreted carefully and future studies are warranted to rule out a type-1 error.


Asunto(s)
Aneurisma Roto/complicaciones , Aneurisma Roto/epidemiología , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/epidemiología , Actividad Solar , Intervalos de Confianza , Bases de Datos Factuales , Femenino , Humanos , Masculino , Distribución de Poisson , Análisis de Regresión , Suiza/epidemiología
9.
J Biol Chem ; 289(46): 31995-32009, 2014 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-25271167

RESUMEN

Late embryogenesis-abundant proteins accumulate to high levels in dry seeds. Some of them also accumulate in response to water deficit in vegetative tissues, which leads to a remarkable association between their presence and low water availability conditions. A major sub-group of these proteins, also known as typical LEA proteins, shows high hydrophilicity and a high percentage of glycine and other small amino acid residues, distinctive physicochemical properties that predict a high content of structural disorder. Although all typical LEA proteins share these characteristics, seven groups can be distinguished by sequence similarity, indicating structural and functional diversity among them. Some of these groups have been extensively studied; however, others require a more detailed analysis to advance in their functional understanding. In this work, we report the structural characterization of a group 6 LEA protein from a common bean (Phaseolus vulgaris L.) (PvLEA6) by circular dichroism and nuclear magnetic resonance showing that it is a disordered protein in aqueous solution. Using the same techniques, we show that despite its unstructured nature, the addition of trifluoroethanol exhibited an intrinsic potential in this protein to gain helicity. This property was also promoted by high osmotic potentials or molecular crowding. Furthermore, we demonstrate that PvLEA6 protein is able to form soluble homo-oligomeric complexes that also show high levels of structural disorder. The association between PvLEA6 monomers to form dimers was shown to occur in plant cells by bimolecular fluorescence complementation, pointing to the in vivo functional relevance of this association.


Asunto(s)
Phaseolus/química , Proteínas de Plantas/química , Secuencia de Aminoácidos , Calorimetría , Cromatografía en Gel , Dicroismo Circular , Reactivos de Enlaces Cruzados/química , Fluorometría , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Datos de Secuencia Molecular , Concentración Osmolar , Unión Proteica , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Homología de Secuencia de Aminoácido , Agua/química
10.
Plant Signal Behav ; 9(5): e28847, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24736593

RESUMEN

Transcription factors are DNA binding proteins that regulate gene expression. The nitrogen fixing symbiosis established between legume plants and soil bacteria is a complex interaction, in which plants need to integrate signals derived from the symbiont and the surrounding environment to initiate the developmental program of nodule organogenesis and the infection process. Several transcription factors that play critical roles in these processes have been reported in the past decade, including proteins of the GRAS and NF-Y families. Recently, we reported the characterization of a new GRAS domain containing-protein that interacts with a member of the C subunit of the NF-Y family, which plays an important role in nodule development and the progression of bacterial infection during the symbiotic interaction. The connection between transcription factors of these families highlights the significance of multimeric complexes in the fabulous capacity of plants to integrate and respond to multiple environmental stimuli.


Asunto(s)
Fabaceae/microbiología , Proteínas de Plantas/fisiología , Simbiosis/fisiología , Factores de Transcripción/fisiología , Factor de Unión a CCAAT/fisiología , Fabaceae/fisiología , Fijación del Nitrógeno , Raíces de Plantas/microbiología , Raíces de Plantas/fisiología , Dominios y Motivos de Interacción de Proteínas
11.
Plant Physiol ; 164(3): 1430-42, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24424321

RESUMEN

A C subunit of the heterotrimeric nuclear factor Y (NF-YC1) was shown to play a key role in nodule organogenesis and bacterial infection during the nitrogen fixing symbiosis established between common bean (Phaseolus vulgaris) and Rhizobium etli. To identify other proteins involved in this process, we used the yeast (Saccharomyces cerevisiae) two-hybrid system to screen for NF-YC1-interacting proteins. One of the positive clones encodes a member of the Phytochrome A Signal Transduction1 subfamily of GRAS (for Gibberellic Acid-Insensitive (GAI), Repressor of GAI, and Scarecrow) transcription factors. The protein, named Scarecrow-like13 Involved in Nodulation (SIN1), localizes both to the nucleus and the cytoplasm, but in transgenic Nicotiana benthamiana cells, bimolecular fluorescence complementation suggested that the interaction with NF-YC1 takes place predominantly in the nucleus. SIN1 is expressed in aerial and root tissues, with higher levels in roots and nodules. Posttranscriptional gene silencing of SIN1 using RNA interference (RNAi) showed that the product of this gene is involved in lateral root elongation. However, root cell organization, density of lateral roots, and the length of root hairs were not affected by SIN1 RNAi. In addition, the expression of the RNAi of SIN1 led to a marked reduction in the number and size of nodules formed upon inoculation with R. etli and affected the progression of infection threads toward the nodule primordia. Expression of NF-YA1 and the G2/M transition cell cycle genes Cyclin B and Cell Division Cycle2 was reduced in SIN1 RNAi roots. These data suggest that SIN1 plays a role in lateral root elongation and the establishment of root symbiosis in common bean.


Asunto(s)
Factor de Unión a CCAAT/metabolismo , Organogénesis , Phaseolus/microbiología , Proteínas de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Nódulos de las Raíces de las Plantas/microbiología , Simbiosis , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Núcleo Celular/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Genes de Plantas/genética , Familia de Multigenes , Especificidad de Órganos/genética , Phaseolus/crecimiento & desarrollo , Phaseolus/metabolismo , Raíces de Plantas/anatomía & histología , Raíces de Plantas/microbiología , Unión Proteica , Interferencia de ARN , Rhizobium/fisiología , Nódulos de las Raíces de las Plantas/metabolismo , Transcripción Genética
12.
Front Plant Sci ; 4: 190, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23805145

RESUMEN

Plants are exposed to different external conditions that affect growth, development, and productivity. Water deficit is one of these adverse conditions caused by drought, salinity, and extreme temperatures. Plants have developed different responses to prevent, ameliorate or repair the damage inflicted by these stressful environments. One of these responses is the activation of a set of genes encoding a group of hydrophilic proteins that typically accumulate to high levels during seed dehydration, at the last stage of embryogenesis, hence named Late Embryogenesis Abundant (LEA) proteins. LEA proteins also accumulate in response to water limitation in vegetative tissues, and have been classified in seven groups based on their amino acid sequence similarity and on the presence of distinctive conserved motifs. These proteins are widely distributed in the plant kingdom, from ferns to angiosperms, suggesting a relevant role in the plant response to this unfavorable environmental condition. In this review, we analyzed the LEA proteins from those legumes whose complete genomes have been sequenced such as Phaseolus vulgaris, Glycine max, Medicago truncatula, Lotus japonicus, Cajanus cajan, and Cicer arietinum. Considering their distinctive motifs, LEA proteins from the different groups were identified, and their sequence analysis allowed the recognition of novel legume specific motifs. Moreover, we compile their transcript accumulation patterns based on publicly available data. In spite of the limited information on these proteins in legumes, the analysis and data compiled here confirm the high correlation between their accumulation and water deficit, reinforcing their functional relevance under this detrimental conditions.

13.
Plant Cell ; 22(12): 4142-57, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21139064

RESUMEN

Legume plants are able to interact symbiotically with soil bacteria to form nitrogen-fixing root nodules. Although specific recognition between rhizobia and legume species has been extensively characterized, plant molecular determinants that govern the preferential colonization by different strains within a single rhizobium species have received little attention. We found that the C subunit of the heterotrimeric nuclear factor NF-Y from common bean (Phaseolus vulgaris) NF-YC1 plays a key role in the improved nodulation seen by more efficient strains of rhizobia. Reduction of NF-YC1 transcript levels by RNA interference (RNAi) in Agrobacterium rhizogenes-induced hairy roots leads to the arrest of nodule development and defects in the infection process with either high or low efficiency strains. Induction of three G2/M transition cell cycle genes in response to rhizobia was impaired or attenuated in NF-YC1 RNAi roots, suggesting that this transcription factor might promote nodule development by activating cortical cell divisions. Furthermore, overexpression of this gene has a positive impact on nodulation efficiency and selection of Rhizobium etli strains that are naturally less efficient and bad competitors. Our findings suggest that this transcription factor might be part of a mechanism that links nodule organogenesis with an early molecular dialogue that selectively discriminates between high- and low-quality symbiotic partners, which holds important implications for optimizing legume performance.


Asunto(s)
Factor de Unión a CCAAT/fisiología , Phaseolus/fisiología , Rhizobium etli/fisiología , Simbiosis/fisiología , Factor de Unión a CCAAT/genética , Factor de Unión a CCAAT/metabolismo , Núcleo Celular/metabolismo , Perfilación de la Expresión Génica , Genes de Plantas , Phaseolus/genética , Raíces de Plantas/metabolismo , Raíces de Plantas/microbiología , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
Asian J Androl ; 12(6): 871-9, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20852650

RESUMEN

Objective measurements are required for computer-aided sperm morphometric analysis (CASMA) machines to distinguish normal from abnormal sperm heads. The morphometric characteristics of spermatozoa in 72 samples of semen and of spermatozoa from 72 other semen samples after swim-up were quantified by the semi-automated Integrated Sperm Analysis System (ISAS) computer-aided system, which measured the sperm head parameters length (L), width (W), area (A), perimeter (P), acrosomal area (Ac), and the derived values L/W and P/A. For each man a homogeneous population of distributions characterized seminal spermatozoa (7 942 cells: median values L 4.4 µm, W 2.8 µm, A 9.8 µm(2), P 12.5 µm, Ac 47.5%, L/W 1.57, P/A 1.27), and there was no significant difference in within- and among-individual variation. Different men could have spermatozoa of significantly different dimensions. Head dimensions for swim-up spermatozoa from different men (4 812 cells) were similar to those in semen, differing only by 2%-5%. The values of L, W and L/W fell within the limits given by the World Health Organization (WHO). Although these samples were not biologically matched, linear mixed-effects statistical analyses permitted valid comparison of the groups. A subpopulation of 404 spermatozoa considered to fit the stringent criteria of WHO 'normal' seminal spermatozoa from both semen and swim-up were characterized by median values (and 95% confidence intervals) of L, 4.3 µm (3.8-4.9), W, 2.9 µm (2.6-3.3), A, 10.2 µm(2) (8.5-12.2), P, 12.4 µm (11.3-13.9), Ac, 49% (36-60), L/W, 1.49 (1.32-1.67) and P/A, 1.22 (1.11-1.35). These median values fall within the 95th centile confidence limits given by WHO, but the confidence intervals for L and W were larger. Although these differences in head dimensions among men and after swim-up could be detected by CASMA, the small differences make it unlikely that technicians would be able to distinguish them. The values could be used as default sperm head values for the CASMA machine used here.


Asunto(s)
Análisis de Semen/métodos , Espermatozoides/citología , Colorantes , Eyaculación , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Procesamiento de Imagen Asistido por Computador/normas , Masculino , Prueba de Papanicolaou , Cabeza del Espermatozoide/ultraestructura , Espermatozoides/ultraestructura
15.
Eur J Endocrinol ; 162(5): 861-7, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20176736

RESUMEN

OBJECTIVE: Current data clearly demonstrate that sports-related chronic repetitive head trauma due to boxing might result in hypopituitarism. However, the mechanism of sports-related traumatic brain injury-induced pituitary dysfunction is still unclear. In order to understand whether autoimmune mechanisms could play a role in the pituitary dysfunction due to sports-related head trauma, we investigated the presence of antipituitary antibodies (APAs) and antihypothalamus antibodies (AHAs) in amateur boxers. PATIENTS AND DESIGN: Sixty-one actively competing (n=44) or retired (n=17) male boxers (mean age, 26 years; range, 17-53) who had been evaluated regarding pituitary functions previously were included in the study. In all boxers and in 60 age/sex-similar normal controls, AHAs and APAs were investigated by an indirect immunofluorescence method. RESULTS: AHAs were detected in 13 of 61 boxers (21.3%), and APAs were detected in 14 of 61 boxers (22.9%), but in none of the normal controls. Pituitary dysfunction was significantly higher in AHA-positive boxers (46.2%) than in AHA-negative boxers (10.4%) (P=0.003). There was a significant association between AHA positivity and hypopituitarism due to boxing (odds ratio: 7.37, 95% confidence interval 1.8-30.8). There was no significant association between APA positivity and hypopituitarism. CONCLUSIONS: This study demonstrates for the first time the presence of AHAs and APAs in boxers who were exposed to sports-related head trauma. Moreover, the present investigation provides preliminary evidence that AHAs are associated with the development of pituitary dysfunction in boxers, thus suggesting that autoimmunity may have a role in the pathogenesis.


Asunto(s)
Autoanticuerpos/análisis , Boxeo/lesiones , Lesiones Encefálicas/complicaciones , Traumatismos Craneocerebrales/complicaciones , Hipopituitarismo/etiología , Hipotálamo/inmunología , Hipófisis/inmunología , Adolescente , Adulto , Autoinmunidad/inmunología , Lesiones Encefálicas/inmunología , Humanos , Masculino , Persona de Mediana Edad
17.
Clin Sci (Lond) ; 114(6): 413-21, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18260829

RESUMEN

LYH (lymphocytic hypophysitis) is an autoimmune disease of the pituitary gland which can present with varying degrees of pituitary hormonal impairment and/or with symptoms related to pituitary enlargement. In this review, we provide an overview of the epidemiology, diagnosis, pathogenesis, treatment, and the role of organ-specific and antipituitary antibodies as potential markers of LYH. In addition, although the mechanisms underlying LYH are not completely understood, the role of prolactin, which plays an important part in maintaining immune system homoeostasis and is increased in the disease, is considered.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Linfocitosis/inmunología , Enfermedades de la Hipófisis/inmunología , Autoanticuerpos/análisis , Enfermedades Autoinmunes/etiología , Enfermedades Autoinmunes/patología , Enfermedades Autoinmunes/terapia , Humanos , Linfocitosis/etiología , Linfocitosis/patología , Linfocitosis/terapia , Sistemas Neurosecretores/fisiopatología , Enfermedades de la Hipófisis/etiología , Enfermedades de la Hipófisis/patología , Enfermedades de la Hipófisis/terapia , Hipófisis/inmunología
18.
Eur J Endocrinol ; 158(2): 147-52, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18230820

RESUMEN

OBJECTIVE: While anti-pituitary antibodies (APAs) were detected in some patients with Sheehan's syndrome (SS) suggesting an autoimmune pituitary involvement in the development of their hypopituitarism, hypothalamic cell anti-hypothalamus antibodies (AHAs) have not been investigated so far. DESIGN: The aim of this study was to evaluate the presence of AHA and APA in SS patients to verify whether an autoimmune hypothalamic-pituitary process can contribute to their late hypopituitarism. METHODS: Twenty women with SS with a duration of disease ranging from 3 to 40 years (median 25.5 years) were enrolled into the study. Out of 20 patients, 12 (60%) had panhypopituitarism and the others had partial hypopituitarism well corrected with appropriate replacement therapy. None of them had clinical central diabetes insipidus. AHA and APA were investigated by immunofluorescence method in all patients. In addition, a four-layer immunofluorescence method was used to verify whether AHA immunostained vasopressin-secreting cells (AVP-c) or not. RESULTS: AHAs were found in 8 out of 20 (40%) and APAs in 7 out of 20 (35%) patients with titers ranging from 1:32 to 1:128 and 1:16 to 1:32 respectively; however, in none of these positive patients AHA immunostained vasopressin cells. None of controls resulted positive for both antibodies. CONCLUSIONS: Patients with SS, even many years after the onset of SS, can show antibodies to pituitary and/or hypothalamic but not AVP-secreting cells. Antibodies to unknown hypothalamic cells (releasing factor-secreting cells) other than APAs suggest that an autoimmune process involving both the hypothalamus and pituitary gland may contribute to late pituitary dysfunction in SS patients.


Asunto(s)
Autoanticuerpos/sangre , Síndrome de Silla Turca Vacía/complicaciones , Hipopituitarismo/inmunología , Hipotálamo/inmunología , Hipófisis/inmunología , Adulto , Anciano , Autoinmunidad , Estudios de Casos y Controles , Síndrome de Silla Turca Vacía/inmunología , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Hipopituitarismo/sangre , Hipopituitarismo/patología , Imagen por Resonancia Magnética , Persona de Mediana Edad , Hipófisis/patología , Hormonas Hipofisarias/administración & dosificación , Hormonas Hipofisarias/sangre , Síndrome , Factores de Tiempo
19.
Ann N Y Acad Sci ; 1107: 129-35, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17804540

RESUMEN

Hyperprolactinemia is often observed in lymphocytic hypophysitis (LYH). To clarify the possible autoimmune pituitary involvement in patients with apparently idiopathic hyperprolactinemia we investigated the presence of antipituitary antibodies (APA) in hyperprolactinemic patients with idiopathic hyperprolactinemia and in those with prolactinoma. Sixty-six hyperprolactinemic patients (52 F, 14 M age range 28-42 years, group 1) were studied. Of them, 34 out of 66 showed clinical features of hyperprolactinemia and subsequently underwent cabergoline therapy; the 32 out of 66 patients without symptoms of hyperprolactinemia did not receive cabergoline therapy. Moreover, 32 patients (24 F/8M, age range 23-44 years) with hyperprolactinemia due to microprolactinoma (group 2) were also studied. APA, by immunofluorescence method, and anterior pituitary function were evaluated in both groups of patients. APA were present in 17 out of 66 (25.7%) patients in group 1 with titers ranging from 1/16 to 1/64. All patients of group 2 were considered APA negative because these antibodies were found at low titer (

Asunto(s)
Autoanticuerpos/inmunología , Hiperprolactinemia/inmunología , Hipófisis/inmunología , Adulto , Femenino , Humanos , Hiperprolactinemia/patología , Masculino
20.
Planta ; 225(5): 1121-33, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17109151

RESUMEN

Plant cell walls undergo dynamic changes in response to different environmental stress conditions. In response to water deficit, two related proline-rich glycoproteins, called p33 and p36, accumulate in the soluble fraction of the cell walls in Phaseolus vulgaris (Covarrubias et al. in Plant Physiol 107:1119-1128, 1995). In this work, we show that p33 and p36 are able to form a 240 kDa oligomer, which is found in the cell wall soluble fraction. We present evidence indicating that the highest accumulation of these proteins in response to water deficit occurs in the growing regions of common bean seedlings, particularly in the phloem tissues. These proteins were detected in P. vulgaris cell suspension cultures, where the p33/p36 ratio was higher under hyperosmotic conditions than in bean seedlings subjected to the same treatment. The results support a role for these proteins during the plant cell response to changes in its water status, and suggest that cell wall modifications are induced in active growing cells of common bean in response to water limitation.


Asunto(s)
Pared Celular/metabolismo , Phaseolus/metabolismo , Floema/fisiología , Proteínas de Plantas/metabolismo , Prolina/metabolismo , Agua/metabolismo , Células Cultivadas , Electroforesis en Gel de Poliacrilamida , Phaseolus/citología , Phaseolus/crecimiento & desarrollo , Proteínas de Plantas/aislamiento & purificación , Abastecimiento de Agua
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