Intraovarian sperm storage in Helicolenus dactylopterus dactylopterus fertilitzation, crypt formation and maintenance of stored sperm

The females of the bluemouth rockfish, Helicolenus dactylopterus dactylopterus (DelaRoche, 1809), store sperm within their ovaries for periods of up to 10 months. Twenty six females with standard lengths between 152 and 257 mm and six males with standard lengths between 253 and 209 mm were caught storage crypts with stored spermatozoa and to describe their evolution over the year. After internal fertilization and once sperm reaches the ovary, a crypt forms probably by an epithelial inclusion at the base of the lamellae of one or several spermatozoa groups that are floating freely in the interlamellar space of the ovarian lumen. Stored spermatozoa have a large cytoplasm bag surrounding their heads. This bag could serve as a nutritive reservoir during the long storage period. Many desmosonal and tight junctions between the crypt cells ensure tha male sex cells are protected against the female immune system

Adaptation to experimental alterations of the operational sex ratio in populations of Drosophila melanogaster.

Theory predicts that males adapt to sperm competition by increasing their investment in testis mass to transfer larger ejaculates. Experimental and comparative data support this prediction. Nevertheless, the relative importance of sperm competition in testis size evolution remains elusive, because experiments vary only sperm competition whereas comparative approaches confound it with other variables, in particular male mating rate. We addressed the relative importance of sperm competition and male mating rate by taking an experimental evolution approach. We subjected populations of Drosophila melanogaster to sex ratios of 1:1, 4:1, and 10:1 (female:male). Female bias decreased sperm competition but increased male mating rate and sperm depletion. After 28 generations of evolution, males from the 10:1 treatment had larger testes than males from other treatments. Thus, testis size evolved in response to mating rate and sperm depletion, not sperm competition. Furthermore, our experiment demonstrated that drift associated with sex ratio distortion limits adaptation; testis size only evolved in populations in which the effect of sex ratio bias on the effective population size had been compensated by increasing the numerical size. We discuss these results with respect to reproductive evolution, genetic drift in natural and experimental populations, and consequences of natural sex ratio distortion.

Anxiety and Psychological Stress Before Prenatal Screening in First-Time Mothers Who Conceived Through IVF/ICSI or Spontaneously.

Mothers' general anxiety, anxiety about the well-being of the child and psychological stress before prenatal testing was studied by comparing women who conceived through in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) with women who conceived naturally. Before the first trimester screening test for Down's syndrome, a group of 51 women who conceived through IVF/ICSI and a group of 54 women who conceived spontaneously completed the State Scale of the State-Trait Anxiety Inventory (S-Anxiety; Spielberger, 1983), the Fear of Bearing a Physically or Mentally Handicapped Child Subscale of the Pregnancy-related Anxiety Questionnaire (PRAQ-R; Huizink et al., 2004), the Psychological Stress Measure (PSM; Lemyre & Tessier, 1988), and the Prenatal Psychosocial Profile (PPP; Curry, Campbell, & Christian, 1994). Women who conceived through IVF/ICSI had more elevated levels of general anxiety and psychological stress than the women who conceived naturally; however, no difference was observed between the two groups for anxiety specifically related to the health of the child. These results underline the need to monitor women's emotional state after conception via IVF/ICSI-when counseling usually ends-and around the time of the first trimester screening. Counseling might thus be extended.

Development of a well-defined medium for the in vitro maturation of immature bovine cumulus-oocyte complexes.

PURPOSE: Our purpose was to develop a well-defined medium for the in vitro maturation (IVM) of immature bovine cumulus-oocyte complexes (COC). METHODS: The COC were cultured in the presence of three protein supplementations: fetal bovine serum (FBS), bovine serum albumin, and Synthetic Serum Substitute. The embryos obtained after in vitro fertilization of IVM oocytes were cocultured with Vero cells and their development to the morula and blastocyst stages was studied. RESULTS: When FBS was absent from the IVM medium, a significantly lower fertilization rate was observed, followed by a decrease in the percentage of embryos reaching the blastocyst stage. When FBS was replaced by a defined protein supplementation, the best results were obtained with Synthetic Serum Substitute. CONCLUSIONS: Adequate protein supplementation of the IVM medium optimizes the fertilization rate and the development of bovine IVM oocytes. The implication of these results in the human field is discussed.

Molecular changes underlying mammalian phenotypic innovation

Mammals are characterized by specific phenotypic traits that include lactation, hair, and relatively large brains with unique structures. Individual mammalian lineages have, in turn, evolved characteristic traits that distinguish them from others. These include obvious anatom��ical differences but also differences related to reproduction, life span, cognitive abilities, be��havior. and disease susceptibility. However, the molecular basis of the diverse mammalian phenotypes and the selective pressures that shaped their evolution remain largely unknown. In the first part of my thesis, I analyzed the genetic factors associated with the origin of a unique mammalian phenotype lactation and I studied the selective pressures that forged the transition from oviparity to viviparity. Using a comparative genomics approach and evolutionary simulations, I showed that the emergence of lactation, as well as the appear��ance of the casein gene family, significantly reduced selective pressure on the major egg-yolk proteins (the vitellogenin family). This led to a progressive loss of vitellogenins, which - in oviparous species - act as storage proteins for lipids, amino acids, phosphorous and calcium in the isolated egg. The passage to internal fertilization and placentation in therian mam��mals rendered vitellogenins completely dispensable, which ended in the loss of the whole gene family in this lineage. As illustrated by the vitellogenin study, changes in gene content are one possible underlying factor for the evolution of mammalian-specific phenotypes. However, more subtle genomic changes, such as mutations in protein-coding sequences, can also greatly affect the phenotypes. In particular, it was proposed that changes at the level of gene reg��ulation could underlie many (or even most) phenotypic differences between species. In the second part of my thesis, I participated in a major comparative study of mammalian tissue transcriptomes, with the goal of understanding how evolutionary forces affected expression patterns in the past 200 million years of mammalian evolution. I showed that, while com��parisons of gene expressions are in agreement with the known species phylogeny, the rate of expression evolution varies greatly among lineages. Species with low effective population size, such as monotremes and hominoids, showed significantly accelerated rates of gene expression evolution. The most likely explanation for the high rate of gene expression evolution in these lineages is the accumulation of mildly deleterious mutations in regulatory regions, due to the low efficiency of purifying selection. Thus, our observations are in agreement with the nearly neutral theory of molecular evolution. I also describe substantial differences in evolutionary rates between tissues, with brain being the most constrained (especially in primates) and testis significantly accelerated. The rate of gene expression evolution also varies significantly between chromosomes. In particular, I observed an acceleration of gene expression changes on the X chromosome, probably as a result of adaptive processes associated with the origin of therian sex chromosomes. Lastly, I identified several individual genes as well as co-regulated expression modules that have undergone lineage specific expression changes and likely under��lie various phenotypic innovations in mammals. The methods developed during my thesis, as well as the comprehensive gene content analyses and transcriptomics datasets made available by our group, will likely prove to be useful for further exploratory analyses of the diverse mammalian phenotypes.

Concepts and Rationale for Regional Nitrogen Rate Guidelines for Corn, April 2006

Nitrogen (N) is typically one of the largest corn fertilization expenses. Nitrogen application is critical because it signifi cantly improves corn yield in many crop rotations. When choosing N rates, producers need to carefully consider both achieving most profi table economic return and advancing environmental stewardship. In 2004, university agronomists from the Corn Belt states began discussions regarding N rate use for corn production. The reasons for the discussions centered on apparent differences in methods for determining N rates across states, misperceptions regarding N rate guidelines, and concerns about application rates as corn yields have climbed to historic levels. An outcome of those discussions was an effort with the objectives to: ��� develop N rate guidelines that could be applicable on a regional basis and ��� identify the most profi table fertilizer N rates for corn production across the Corn Belt. This publication provides an overview of corn N fertilization in regard to rate of application, investigates concepts for determining economic application rates, and describes a suggested regional approach for developing corn N rate guidelines directly from recent research data.

Avalia����o da infesta����o de insetos-praga associados �� batata (Solanum tuberosum L.) sob efeito de nutrientes nitrogenados e pot��ssicos e teores acumulados de amino��cidos livres nas cultivares Achat e Monalisa

Evaluation of insect-pest infestation associated to potato (Solanum tuberosum L.) under effect of nitrogen and potassium fertilizers and the accumulated amount of free aminoacids in Achat and Monalisa cultivars. The objective of this work was to evaluate the occurence of insect-pests on potato plants influenced by dosages of nitrogen and potassium accumulated in plant organs. A total of 169 plants of the Achat and Monalisa cultivars were evaluated to determine the presence-absence of Diabrotica speciosa Germar, 1824 and Agrotis ipsilon H��fnagel, 1767. The experiment was carried out and executed at the Universidade Federal Fluminense, and the delineation was complete randomized block design, with four replication and nine treatments, using three fertilization level (0; 75 and 150 Kg/ha) with N-urea + KCl. The aminoacid levels were adjusted by the Leucine standard-curve (��g/l), using the Ninhydrin method, at 570 nm. The results showed that the tubercles of Monalisa accumulated high free aminoacid levels with 7,95% in the treatment N1K2 and 7,75% in the N2K1.These treatments, induced the infestation by D. speciosa larvae in 27,03%, when the aminoacid level was 2,01 �� 0,58% (X �� EP), with probability of 0,0196<P<0,05. The studied cultivars showed a diferential behavior, especially, in relationship to the N and K metabolism, resulting in the accumulation of free aminoacids, and consequently in the pest infestation increment. The results indicated that the aminoacid level increasing affects the tubercles production, mainly in the Monalisa cultivar, in winter cropping with long dry periods.

The In Vitro Mass-Produced Model Mycorrhizal Fungus, Rhizophagus irregularis, Significantly Increases Yields of the Globally Important Food Security Crop Cassava.

The arbuscular mycorrhizal symbiosis is formed between arbuscular mycorrhizal fungi (AMF) and plant roots. The fungi provide the plant with inorganic phosphate (P). The symbiosis can result in increased plant growth. Although most global food crops naturally form this symbiosis, very few studies have shown that their practical application can lead to large-scale increases in food production. Application of AMF to crops in the tropics is potentially effective for improving yields. However, a main problem of using AMF on a large-scale is producing cheap inoculum in a clean sterile carrier and sufficiently concentrated to cheaply transport. Recently, mass-produced in vitro inoculum of the model mycorrhizal fungus Rhizophagus irregularis became available, potentially making its use viable in tropical agriculture. One of the most globally important food plants in the tropics is cassava. We evaluated the effect of in vitro mass-produced R. irregularis inoculum on the yield of cassava crops at two locations in Colombia. A significant effect of R. irregularis inoculation on yield occurred at both sites. At one site, yield increases were observed irrespective of P fertilization. At the other site, inoculation with AMF and 50% of the normally applied P gave the highest yield. Despite that AMF inoculation resulted in greater food production, economic analyses revealed that AMF inoculation did not give greater return on investment than with conventional cultivation. However, the amount of AMF inoculum used was double the recommended dose and was calculated with European, not Colombian, inoculum prices. R. irregularis can also be manipulated genetically in vitro, leading to improved plant growth. We conclude that application of in vitro R. irregularis is currently a way of increasing cassava yields, that there is a strong potential for it to be economically profitable and that there is enormous potential to improve this efficiency further in the future.

Ejaculation failure on the day of oocyte retrieval for IVF: case report.

Unexpected ejaculation failure on the day of oocyte retrieval for IVF occurs once or twice a year in our Reproductive Medicine Unit, where approximately 500 oocyte retrievals are performed each year. Two clinical situations which occurred in 2001 are presented. In the first case, sperm were finally obtained by epididymal aspiration and resulted in the fertilization of five oocytes by ICSI. The transfer of two fresh embryos did not result in a pregnancy and the three supernumerary zygotes were cryopreserved. The male patient presented an anxio-depressive episode necessitating psychiatric hospitalization 1 week after the oocyte retrieval. In the second case, no sperm were obtained and the four oocytes were therefore lost. The couple went through a crisis in their relationship and tried another cycle of IVF 10 months later, after the preventive cryopreservation of a sperm sample. On the day of oocyte retrieval the patient was unable to produce a fresh sample but three zygotes were obtained through ICSI using the back-up cryopreserved sperm. Two embryos were transferred but no pregnancy ensued. The clinical decision-making processes for these two cases are described, as well as the measures employed to help prevent these unfortunate situations.

Adiponectin isoform distribution in serum and in follicular fluid of women undergoing treatment by ICSI.

Adiponectin is an adipokine, present in the circulation in comparatively high concentrations and different molecular weight isoforms. For the first time, the distribution of these isoforms in serum and follicular fluid (FF) and their usefulness as biological markers for infertility investigations was studied. In vitro study. University based hospital. Fifty-four women undergoing intracytoplasmic sperm injection (ICSI). Oocytes were retrieved, fertilized in vitro using ICSI, and the resulting embryos transferred. Serum was collected immediately prior to oocyte retrieval. Adiponectin isoforms (high molecular weight (HMW), medium and low molecular weight) were determined in serum and FF. Total adiponectin and the different isoform levels were compared with leptin and ovarian steroid concentrations. Adiponectin isoforms in serum and FF. Adiponectin isoform distribution differed between serum and FF; the HMW fraction made up half of all adiponectin in the serum but only 23.3% in the FF. Total and HMW adiponectin in both serum and FF correlated negatively with the body mass index and the concentration of leptin. No correlations were observed for total adiponectin or its isoforms with estradiol, progesterone, anti-Mullerian hormone, inhibin B, or the total follicle stimulating hormone (FSH) dose administered during the ovarian stimulation phase. This study shows for the first time that adiponectin isoform distribution varies between the serum and FF compartments in gonadotropin stimulated patients. A trend towards higher HMW adiponectin serum levels in successful ICSI cycles compared to implantation failures was observed; studies with larger patient groups are required to confirm this observation.

Respostas do cacaueiro �� aplica����o de N, P e K em dois solos da Amaz��nia Brasileira

A cacauicultura da Amaz��nia est�� implantada em solos eutr��ficos, com predomin��ncia da Terra Roxa Estruturada, e em Latossolos ou Podz��licos distr��ficos, sendo desconhecidas as limita����es nutricionais desses solos na fase produtiva do cacaueiro. As respostas do cacaueiro �� aplica����o de N, P e K foram determinadas em dois experimentos instalados nos munic��pios de Medicil��ndia, ao longo da Rodovia Transamaz��nica, e Benevides, Par��, em solos das unidades Terra Roxa Estrutura eutr��fica (TR) e Latossolo Amarelo (LA), respectivamente. As lavouras de cacau do h��brido Sca 6 x Be 10 foram implantadas ap��s o corte e queima da mata prim��ria, utilizando-se, como esquema experimental, um fatorial NPK 2�� com tratamentos adicionais de P. Os resultados obtidos demonstraram que o P foi o principal nutriente que limitou a produ����o, provocando incrementos de produtividade (P < 0,01) da ordem de 13,7% (110 kg ha-1) e 44,3% (214 kg ha-1) nos solos TR e LA, respectivamente, na m��dia do per��odo 1987 a 1993. O K tamb��m aumentou (P < 0,01) o rendimento de am��ndoas secas de cacau no solo LA, verificando-se, ainda, intera����es significativas (P < 0,05) entre N x K e P x K neste solo. A resposta linear do cacaueiro ao P e o aumento ou diminui����o da taxa de infec����o de vassoura-de-bruxa ao N, P e K evidenciam a necessidade de novas pesquisas para definir a dosagem econ��mica de P, de K e o efeito da intera����o dos nutrientes com a enfermidade.

Efeitos do fracionamento da aduba����o mineral, da aduba����o org��nica e da calagem na produtividade e incid��ncia de vassoura-de-bruxa em cacaueiros da Amaz��nia

A resposta do cacaueiro �� aplica����o de micronutrientes, mat��ria org��nica, calc��rio e fracionamento da aduba����o foi determinada em dois experimentos, instalados em solos das unidades Terra Roxa estruturada eutr��fica (TR) e Latossolo Amarelo (LA), no Estado do Par��, no per��odo de 1988 a 1993. As lavouras de cacau do h��brido Sca 6 x Be 10 foram implantadas pelo sistema de derrubada total e queima da floresta prim��ria, utilizando-se sombreamento provis��rio de bananeira (Musa spp.) e permanente de Erythrina poeppigiana ou Gmelina arborea. Os tratamentos foram distribu��dos em blocos casualizados, com tr��s repeti����es, sendo a parcela constitu��da de 20 plantas ��teis. Os resultados de produ����o de cacau demonstraram que n��o houve intera����o significativa entre tratamentos e solos ou ano de condu����o do experimento. O fracionamento da aduba����o NPK em tr��s aplica����es/ano e a aduba����o NPK + Zn foram os melhores tratamentos, provocando incrementos (P < 0,05) na produtividade do cacaueiro da ordem de 27,5% e 10,9%, respectivamente. A menor incid��ncia (P < 0,05) de frutos atacados pela enfermidade vassoura-de-bruxa, causada pelo fungo Crinipellis perniciosa, foi observada nos tratamentos em que se aplicaram uma mistura de micronutrientes (B, Cu, Zn, Fe e Mo) ou esterco de gado na dosagem de 5 t ha-1; as porcentagens de frutos doentes dos demais tratamentos n��o diferiram da aduba����o NPK (testemunha). Para o aumento da produtividade, a estrat��gia de aduba����o mais eficiente foi o fracionamento da aduba����o NPK (60 kg ha-1 de N, P(2)0(5) e K(2)0) em tr��s aplica����es ao ano. O efeito de micronutrientes e do esterco de gado na infec����o da vassoura-de-bruxa merece ser investigado com mais aten����o.

pH como un trazador de la variabilidad biogeoqu��mica en el Sistema de Humboldt

Se analiz�� informaci��n sobre par��metros biogeoqu��micos como pH, CO2 parcialmente disuelto, clorofila-a, ox��geno, salinidad y temperatura, obtenidos en el Sistema de Humboldt frente a Per�� en los a��os 2007-2009, a fin de comprender la importancia del pH como una variable clave para trazar la variabilidad biogeoqu��mica del Sistema de Afloramiento de Humboldt. Las Aguas Costeras Fr��as (ACF) ricas en nutrientes evidencian una relaci��n inversa con el pH, en ese sentido valores de 7,6 a 8,0 se encontraron asociados a la ocurrencia de eventos de afloramiento; en condiciones fr��as como La Ni��a 2007 el pH predominante se encuentra por debajo de 8,0, y en el caso de las Aguas Subtropicales Superficiales presentan un pH entorno a 8,3. La productividad en los veranos se incrementa debido a factores como la intensidad de luz gener��ndose n��cleos de clorofila-a superiores a 10,0 ��g.L-1; como constituyentes de la reacci��n bioqu��mica de fotos��ntesis se tiene en cuenta la forma inmediata del compuesto CO2 y el consumo de iones hidronio; en situaciones extremas de fertilizaci��n, se tiene elevado pH entre 8,2 e inclusive 9,0, en donde los contenidos de ox��geno disuelto superan los 6,0 mL.L-1.

Reproducci��n inducida del s��balo cola roja Brycon cephalus (G��nther, 1869). Amazon��a peruana: Iquitos

The experiment was conducted at the Aquaculture Station ���Amazonia Aquaculture Service���. We worked with 13 females and 16 males. The main objectives was the inducing breeding with carp pituitary extract. All females spawned, however, five females with negative results on fertility. In an average temperature of 28.12��0.61 ��C, it takes 5.68��0.53 hours for spawning or 159.01��14.45 hours-grade. The females of 4 years of 2310��143.2 g, fertilization rate achieved, over 66% on average 1497.60��14,57 eggs are per gram, fertilization and hatching rate of 68.80��1.9% and 53.59��8.7% respectively. Hatching occurred at 11.67��0.32 hours, the water temperature was 28.25��0.09 ��C, so that the hatching 331.07��12.56 required hour���s degree.

Altera����es qu��micas do solo e crescimento do milho decorrentes da adi����o de lodos de curtume

O presente trabalho foi elaborado com o objetivo de avaliar as altera����es qu��micas e o crescimento de plantas de milho em um Planossolo Hidrom��rfico ap��s a aplica����o de res��duos de curtume. Foram utilizados o lodo proveniente do decantador prim��rio (lodo com cromo), nas doses correspondentes �� aplica����o de 250 e 500mgkg-1 de Cr (13,8 e 27,6Mgha-1, respectivamente), e o efluente do caleiro (lodo do caleiro), nas doses de 10,25 e 20,50Mgha-1. O experimento foi realizado em vasos mantidos em casa de vegeta����o durante 108dias. A aplica����o m��xima de lodo do caleiro elevou o pH de 4,9 para 5,8 e os teores de Ca do solo de 0,5 para 3,2cmol c dm-3, resultando em rendimentos de milho equivalentes aos obtidos com aduba����o mineral mais calagem. A adi����o de lodo com cromo mais calc��rio elevou o teor de Ntotal do solo de 0,6 para 0,7gkg-1, resultando em rendimentos tamb��m semelhantes aos obtidos com o tratamento NPK+calc��rio. Os teores de Cr no solo permaneceram abaixo do limite m��ximo permitido (500mgkg-1).