100 resultados para spermatozoa motility


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Objective: To study the effect of freeze-thaw on embryos derived from intracytoplasmic sperm injection (ICSI) using surgically retrieved and ejaculated spermatozoa. Design: Retrospective study. Setting: Private IVF center. Patient(s): Three hundred eighty-three patients undergoing frozen-thawed ET cycles. Intervention(s): Testicular sperm aspiration (TESA) or percutaneous epididymal sperm aspiration (PESA) were the sperm surgical retrieval methods used for ICSI. Embryos resulting from ICSI using Surgically retrieved and ejaculated spermatozoa were frozen, thawed, and transferred. Main Outcome Measure(s): Post-thaw survival, implantation, and pregnancy rates. Result(s): No differences were found between the ejaculated sperm and TESA/PESA groups in terms of post-thaw survival rate (68.4% vs. 66.1%, respectively), pregnancy rate (20.1% vs. 16.1%), and implantation rate (10.6% vs. 12.7%). Similar results were found for those variables when comparing TESA and PESA groups. Conclusion(s): Cleavage embryos arising from ICSI cycles using testicular and epididymal spermatozoa can be frozen with survival, pregnancy,and implantation rates comparable to those obtained with ejaculated spermatozoa. (Fertil Steril (R) 2009;91:727-32. (C) 2009 by American Society for Reproductive Medicine.)

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Cisplatin is one of the most widely used and effective chemotherapeutic agents for the treatment of several human malignancies. This study evaluated the effects of peri-pubertal cisplatin administration on several reproductive end-points and the reversibility of these effects in adulthood. Peri-pubertal Wistar male rats (45 days old) were divided into two groups: control (saline 0.9%) and cisplatin (1 mg/kg/day, 5 days/week, for 3 weeks, i.p.). The study was conducted in two steps and evaluations were performed at ages of 66 (post-pubertal age) and 140 (adult age) days on: (i) organ weights, serum gonadotropins and testosterone levels, sperm counts, motility and morphology, testicular histomorphometry, spermatogenesis kinetics, Sertoli cell number and in situ detection of apoptotic germ cells and (ii) sexual behaviour, fertility and intratesticular testosterone. At the end of cisplatin therapy, rats showed reductions in sperm production and reserves, sperm with progressive movement, tubular diameter, intratesticular testosterone and fertility potential, but increased numbers of TUNEL-positive seminiferous tubules, immotile sperm and pre-implantation losses compared with control. Moreover, cisplatin-treated post-pubertal rats displayed impaired testicular histopathology and sexual behaviour. Serum gonadotropins and testosterone levels, sperm morphology, spermatogenesis kinetics and Sertoli cell number were comparable between experimental groups at both ages. Alterations found in post-puberty were recovered at adulthood, except for sperm motility and damage to testicular histology. The persistence of these cisplatin effects, despite the unaltered fertility after natural mating in rats, may have implications for reproductive function of young boys undergoing cancer therapy, given the lower reproductive efficiency in human beings compared with rats.

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Radial glia in the developing optic tectum express the key guidance molecules responsible for topographic targeting of retinal axons. However, the extent to which the radial glia are themselves influenced by retinal inputs and visual experience remains unknown. Using multiphoton live imaging of radial glia in the optic tectum of intact Xenopus laevis tadpoles in conjunction with manipulations of neural activity and sensory stimuli, radial glia were observed to exhibit spontaneous calcium transients that were modulated by visual stimulation. Structurally, radial glia extended and retracted many filopodial processes within the tectal neuropil over minutes. These processes interacted with retinotectal synapses and their motility was modulated by nitric oxide (NO) signaling downstream of neuronal NMDA receptor (NMDAR) activation and visual stimulation. These findings provide the first in vivo demonstration that radial glia actively respond both structurally and functionally to neural activity, via NMDAR-dependent NO release during the period of retinal axon ingrowth.

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Ion channels have been assigned a pivotal importance in various sperm functions and are therefore promising targets for contraceptive development. The lack of data on channel functionality and pharmacology has hampered this goal. This is a consequence of technical problems of applying electrophysiological techniques to spermatozoa due to their small size and form. By using a laminin coating to increase adherence of spermatozoa and nystatin in the patch pipette for pore formation, we have adapted the whole-cell recording technique to study currents in mature uncapacitated bovine spermatozoa. Employing these conditions, in the head region, patched spermatozoa could be transferred into the whole-cell configuration. For the first time we document an outward rectifying current in mature bovine spermatozoa was blocked by tetraethyl ammonium (TEA) chloride. The observation of a shift in the reversal potential as a response to changes in the extracellular concentration of K+ ions allowed us to identify this current as K+ selective. This result shows that K+ channels in the head region of mature uncapacitated bovine spermatozoa can be suitably investigated using the whole-cell recording patch-clamp technique.

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Xylella fastidiosa is an important phytopathogenic bacterium that causes many serious plant diseases, including Pierce`s disease of grapevines. Disease manifestation by X. fastidiosa is associated with the expression of several factors, including the type IV pili that are required for twitching motility. We provide evidence that an operon, named Pil-Chp, with genes homologous to those found in chemotaxis systems, regulates twitching motility. Transposon insertion into the pilL gene of the operon resulted in loss of twitching motility (pilL is homologous to cheA genes encoding kinases). The X. fastidiosa mutant maintained the type IV pili, indicating that the disrupted pilL or downstream operon genes are involved in pili function, and not biogenesis. The mutated X. fastidiosa produced less biofilm than wild-type cells, indicating that the operon contributes to biofilm formation. Finally, in planta the mutant produced delayed and less severe disease, indicating that the Pil-Chp operon contributes to the virulence of X. fastidiosa, presumably through its role in twitching motility.

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This paper reports a rare case of acute severe orbital abscess manifested 2 days after a facial trauma without bone fracture in a 20-year-old Afro-American female. The symptoms worsened within the 24 h prior to hospital admission resulting in visual disturbances such as diplopia and photophobia. The clinical findings at the first consultation included fever, periorbital swelling and redness, ptosis, proptosis and limitation of ocular movements upwards, downwards, to the right and to the left. Computed tomography scan showed proptosis with considerable soft tissue swelling on the left side and no fracture was evidenced in the facial skeleton, including the zygomatic-orbital complex. After hospital admission and antibiotic therapy intravenously the patient was conducted to the operation room and submitted to incision and drainage under general anesthesia. The orbit was approached thorough both eyelids and the maxillary sinus was reached only through the Caldwell-Luc approach. The postoperative period was uneventful and the rapid improvement of symptoms was remarkable. Visual acuity and ocular motility returned to the normal ranges within 2 days after the surgical intervention. After 12 postoperative days, the patient presented with significative improvement in the ptosis and proptosis, and acceptable scars.

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Flavobacterium columnare is the causative agent of columnaris disease in freshwater fish, implicated in skin and gill disease, often causing high mortality. The aim of this study was the isolation and characterization of Flavobacterium columnare in tropical fish in Brazil. Piracanjuba (Brycon orbignyanus), pacu (Piaractus mesopotamicus), tambaqui (Colossoma macropomum) and cascudo (Hypostomus plecostomus) were examined for external lesions showing signs of colunmaris disease such as greyish white spots, especially on the head, dorsal part and caudal fin of the fish. The sampling comprised 50 samples representing four different fish species selected for study. Samples for culture were obtained by skin and kidney scrapes with a sterile cotton swabs of columnaris disease fish and streaked onto Carlson and Pacha (1968) artificial culture medium (broth and solid) which were used for isolation. The strains in the liquid medium were Gram negative, long, filamentous, exhibited flexing movements (gliding motility), contained a large number of long slender bacteria and gathered into ‘columns'. Strains on the agar produced yellow-pale colonies, rather small, flat that had rhizoid edges. A total of four Flavobacterium columnare were isolated: 01 Brycon orbignyanus strain, 01 Piaractus mesopotamicus strain, 01 Colossoma macropomum strain, and 01 Hypostomus plecostomus strain. Biochemical characterization, with its absorption of Congo red dye, production of flexirubin-type pigments, H2S production and reduction of nitrates proved that the isolate could be classified as Flavobacterium columnare.

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Lepidocharax, new genus, and Lepidocharax diamantina and L. burnsi new species from eastern Brazil are described herein. Lepidocharax is considered a monophyletic genus of the Stevardiinae and can be distinguished from the other members of this subfamily except Planaltina, Pseudocorynopoma, and Xenurobrycon by having the dorsal-fin origin vertically aligned with the anal-fin origin, vs. dorsal fin origin anterior or posterior to anal-fin origin. Additionally the new genus can be distinguished from those three genera by not having the scales extending over the ventral caudal-fin lobe modified to form the dorsal border of the pheromone pouch organ or to represent a pouch scale in sexually mature males. In this paper, we describe these two recently discovered species and the ultrastructure of their spermatozoa.

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Esta pesquisa caracteriza os estádios de desenvolvimento dos testículos e canais deferentes da lagosta Panulirus echinatus Smith, 1869 a partir da relação entre seus aspectos macroscópicos, microscópicos e a relação gonadossomática (RGS). Através de amostragem mensal (novembro de 1999 a outubro de 2000) foram capturados 1716 machos, empregando-se redes de espera de fundo. Retirou-se a região dorsal da carapaça para avaliação dos órgãos reprodutivos. Os testículos e canais deferentes foram dissecados, pesados, fixados em solução de Bouin e submetidos aos procedimentos histológicos. A análise microscópica dos órgãos reprodutivos foi avaliada pela presença ou ausência de espermatozóides nos testículos e canais deferentes. Esta, quando associada a macroscopia (mudança de cor, tamanho, diâmetro e desenvolvimento de espermatóforo) e a relação gonadossomática (RGS), possibilitou a caracterização de três estádios de desenvolvimento: imaturo, intermediário e maturo. Ficou evidenciada que a maturidade dos testículos precedeu a maturidade dos canais deferentes. Para avaliar se a RGS é um bom indicador quantitativo dos estádios de maturidade, um teste t (alfa = 0,05) foi usado e constatou diferença significativa nas médias da RGS. A RGS pode ser utilizada como indicadora dos estádios de maturidade para P. echinatus.

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To validate a practical technique of simultaneous evaluation of the plasma, acrosomal and mitochondrial membranes in equine spermatozoa three fluorescent probes (PI, FITC-PSA and MITO) were associated. Four ejaculates from three stallions (n=12) were diluted in TALP medium and split into 2 aliquots, 1 aliquot was flash frozen in liquid nitrogen to induce damage in cellular membranes. Three treatments were prepared with the following fixed ratios of fresh semen: flash frozen semen: 100:0 (T100), 50:50 (T50), and 0:100 (T0). A 150-µL aliquot of diluted semen of each treatment was added of 2 µL of PI, 2 µL of MITO and 80 µL of FITC-PSA; incubated at 38.5ºC/8 min, and sperm cells were evaluated by epifluorescent microscopy. Based in regression analysis, this could be an efficient and practical technique to assess damage in equine spermatozoa, as it was able to determine the sperm percentage more representative of the potential to fertilize the oocyte.

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We describe the male reproductive system of the intertidal hermit crab Calcinus tihicen, with emphasis on the sexual apparatus, spermatophore, and spermatozoa. The crabs were collected on the rocky shore of Praia Grande Beach, Ubatuba, southeastern Brazil. The morphological analysis, based on 30 specimens, was made with the use of a stereomicroscope, an optical microscope, and scanning and transmission electron microscopes. The male reproductive system is composed of a pair of juxtaposed testes, located dorsally in the pleon. From each testis emerges a vas deferens that links it to the exterior by the gonopores. located on the base of the fifth pair of pereiopods. The vas deferens has three macroscopically distinct regions that contain spermatophores in different stages of maturation. The spermatophore morphology is similar to that of other members of Paguroidea, having a distal, nearly spherical ampulla containing spermatozoa; an approximately cylindrical peduncle and a proximal foot connecting the spermatophores. We describe, for the first time, the variability in the spermatophore morphology and size in the three regions of the vas deferens using the type species of the genus Calcinus. The spermatozoa have three main regions (the acrosomal vesicle, the nucleus, and the cytoplasm). The morphological similarity of the male reproductive system of C. tihicen with previously studied species of Diogenidae is an indicative of complex phylogenetic relationships among the members of the genus.

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We have adapted an actin-mosin motility assay to examine the interactions in vitro between actin cables isolated from the giant internodal cells of the freshwater alga, Nitella, and pigment granules extracted from red ovarian chromatophores of the freshwater palaemonid shrimp, Macrobrachium olfersi. The chromatophore pigment mass consists of large (0.5-1.0-mu m diameter) membrane-bounded granules, and small (140-nm diameter), a membranous granules, both structurally continuous with the abundant smooth endoplasmic reticulum. Our previous immunocytochemical studies show a myosin motor to be stably associated with the pigment mass; however, to which granule type or membrane the myosin motor is attached is unclear. Here, we show that sodium vanadate, a myosin ATPase inhibitor, markedly increases the affinity of isolated, large, membrane-bounded granules for Nitella actin cables to which they become permanently attached. This interaction does not occur in granule preparations containing ATP with uninhibited, active myosin without vanadate. We propose that a stable state of elevated affinity is established between the granule-located myosin motor and the Nitella actin cables, resulting from a vanadate-inhibited acto-myosin-ADP complex. This finding provides further evidence for a myosin motor positioned on the surface of the membrane-bounded pigment granules in shrimp ovarian chromatophores.

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Background: Melanoma progression occurs through three major stages: radial growth phase (RGP), confined to the epidermis; vertical growth phase (VGP), when the tumor has invaded into the dermis; and metastasis. In this work, we used suppression subtractive hybridization (SSH) to investigate the molecular signature of melanoma progression, by comparing a group of metastatic cell lines with an RGP-like cell line showing characteristics of early neoplastic lesions including expression of the metastasis suppressor KISS1, lack of alpha v beta 3-integrin and low levels of RHOC. Methods: Two subtracted cDNA collections were obtained, one (RGP library) by subtracting the RGP cell line (WM1552C) cDNA from a cDNA pool from four metastatic cell lines (WM9, WM852, 1205Lu and WM1617), and the other (Met library) by the reverse subtraction. Clones were sequenced and annotated, and expression validation was done by Northern blot and RT-PCR. Gene Ontology annotation and searches in large-scale melanoma expression studies were done for the genes identified. Results: We identified 367 clones from the RGP library and 386 from the Met library, of which 351 and 368, respectively, match human mRNA sequences, representing 288 and 217 annotated genes. We confirmed the differential expression of all genes selected for validation. In the Met library, we found an enrichment of genes in the growth factors/receptor, adhesion and motility categories whereas in the RGP library, enriched categories were nucleotide biosynthesis, DNA packing/repair, and macromolecular/vesicular trafficking. Interestingly, 19% of the genes from the RGP library map to chromosome 1 against 4% of the ones from Met library. Conclusion: This study identifies two populations of genes differentially expressed between melanoma cell lines from two tumor stages and suggests that these sets of genes represent profiles of less aggressive versus metastatic melanomas. A search for expression profiles of melanoma in available expression study databases allowed us to point to a great potential of involvement in tumor progression for several of the genes identified here. A few sequences obtained here may also contribute to extend annotated mRNAs or to the identification of novel transcripts.

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A century after its discovery, Chagas' disease still represents a major public health challenge in Latin America. Moreover, because of growing population movements, an increasing number of cases of imported Chagas' disease have now been detected in non-endemic areas, such as North America and some European countries. This parasitic zoonosis, caused by Trypanosoma cruzi, is transmitted to humans by infected Triatominae insects, or occasionally by non-vectorial mechanisms, such as blood transfusion, mother to fetus, or oral ingestion of materials contaminated with parasites. Following the acute phase of the infection, untreated individuals enter a chronic phase that is initially asymptomatic or clinically unapparent. Usually, a few decades later, 40-50% of patients develop progressive cardiomyopathy and/or motility disturbances of the oesophagus and colon. In the last decades several interventions targeting primary, secondary and tertiary prevention of Chagas' disease have been attempted. While control of both vectorial and blood transfusion transmission of T cruzi (primary prevention) has been successful in many regions of Latin America, early detection and aetiological treatment of asymptomatic subjects with Chagas' disease (secondary prevention) have been largely underutilised. At the same time, in patients with established chronic disease, several pharmacological and non-pharmacological interventions are currently available and have been increasingly used with the intention of preventing or delaying complications of the disease (tertiary prevention). In this review we discuss in detail each of these issues.

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AIM: To evaluate the effects of meal size and three segmentations on intragastric distribution of the meal and gastric motility, by scintigraphy. METHODS: Twelve healthy volunteers were randomly assessed, twice, by scintigraphy. The test meal consisted of 60 or 180 mL of yogurt labeled with 64 MBq (99m)Tc-tin colloid. Anterior and posterior dynamic frames were simultaneously acquired for 18 min and all data were analyzed in MatLab. Three proximal-distal segmentations using regions of interest were adopted for both meals. RESULTS: Intragastric distribution of the meal between the proximal and distal compartments was strongly influenced by the way in which the stomach was divided, showing greater proximal retention after the 180 mL. An important finding was that both dominant frequencies (1 and 3 cpm) were simultaneously recorded in the proximal and distal stomach; however, the power ratio of those dominant frequencies varied in agreement with the segmentation adopted and was independent of the meal size. CONCLUSION: It was possible to simultaneously evaluate the static intragastric distribution and phasic contractility from the same recording using our scintigraphic approach. (C) 2010 Baishideng. All rights reserved.