966 resultados para Sperm injections, intracytoplasmic


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Mode of access: Internet.

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Study Design. A systematic review of randomized and quasi-randomized controlled trials. Objectives. To determine the efficacy of prolotherapy injections in adults with chronic low back pain. Summary of Background Data. Prolotherapy is an injection-based treatment for chronic low back pain. Proponents of prolotherapy suggest that some back pain stems from weakened or damaged ligaments. Repeatedly injecting them with irritant solutions is thought to strengthen the ligaments and reduce pain and disability. Prolotherapy protocols usually include co-interventions to enhance the effectiveness of the injections. Methods. The authors searched MEDLINE, EMBASE, CINAHL, and Science Citation Index up to January 2004, and the Cochrane Controlled Trials Register 2004, issue 1, and consulted content experts. Both randomized and quasi-randomized controlled trials comparing prolotherapy injections to control injections, either alone or in combination with other treatments, were included. Studies had to include measures of pain and disability before and after the intervention. Two reviewers independently selected the trials and assessed them for methodologic quality. Treatment and control group protocols varied from study to study, making meta-analysis impossible. Results. Four studies, all of high quality and with a total of 344 participants, were included. All trials measured pain and disability levels at 6 months, three measured the proportion of participants reporting a greater than 50% reduction in pain or disability scores from baseline to 6 months. Two studies showed significant differences between the treatment and control groups for those reporting more than 50% reduction in pain or disability. Their results could not be pooled. In one, cointerventions confounded interpretation of results; in the other, there was no significant difference in mean pain and disability scores between the groups. In the third study, there was little or no difference between groups in the number of individuals who reported more than 50% improvement in pain and disability. The fourth study reporting only mean pain and disability scores showed no differences between groups. Conclusions. There is conflicting evidence regarding the efficacy of prolotherapy injections in reducing pain and disability in patients with chronic low back pain. Conclusions are confounded by clinical heterogeneity among studies and by the presence of co-interventions. There was no evidence that prolotherapy injections alone were more effective than control injections alone. However, in the presence of co-interventions, prolotherapy injections were more effective than control injections, more so when both injections and co-interventions were controlled concurrently.

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Objectives. To assess the efficacy of a prolotherapy injection and exercise protocol in the treatment of chronic nonspecific low back pain. Design. Randomized controlled trial with two- by- two factorial design, triple- blinded for injection status, and single- blinded for exercise status. Setting. General practice. Participants. One hundred ten participants with nonspecific low- back pain of average 14 years duration were randomized to have repeated prolotherapy ( 20% glucose/ 0.2% lignocaine) or normal saline injections into tender lumbo- pelvic ligaments and randomized to perform either flexion/ extension exercises or normal activity over 6 months. Main outcome measures: Pain intensity ( VAS) and disability scores ( Roland- Morris) at 2.5, 4, 6, 12, and 24 months. Results. Follow- up was achieved in 96% at 12 months and 80% at 2 years. Ligament injections, with exercises and with normal activity, resulted in significant and sustained reductions in pain and disability throughout the trial, but no attributable effect was found for prolotherapy injections over saline injections or for exercises over normal activity. At 12 months, the proportions achieving more than 50% reduction in pain from baseline by injection group were glucose- lignocaine: 0.46 versus saline: 0.36. By activity group these proportions were exercise: 0.41 versus normal activity: 0.39. Corresponding proportions for > 50% reduction in disability were glucose- lignocaine: 0.42 versus saline 0.36 and exercise: 0.36 versus normal activity: 0.38. There were no between group differences in any of the above measures. Conclusions. In chronic nonspecific low- back pain, significant and sustained reductions in pain and disability occur with ligament injections, irrespective of the solution injected or the concurrent use of exercises.

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Acrosomal development in the early spermatid of the rufous hare wallaby shows evidence of formation of an acrosomal granule, similar to that found in eutherian mammals, the Phascolarctidae and Vombatidae. Unlike the other members of the Macropodidae so far examined, the acrosome of this species appears to be fully compacted at spermiation and extends evenly over 90% of the dorsal aspect of the nucleus. During spermiogenesis, the nucleus of the rufous hare wallaby spermatid showed evidence of uneven condensation of chromatin; this may also be related to the appearance of unusual nucleoplasm evaginations from the surface of the fully condensed spermatid. This study was unable to find evidence of the presence of Sertoli cell spurs or nuclear rotation during spermiogenesis in the rufous hare wallaby. The majority of spermatozoa immediately before spermiation had a nucleus that was essentially perpendicular to the long axis of the sperm tail. Nuclei of spermatozoa found in the process of being released or isolated in the lumen of the seminiferous tubule were rotated almost parallel to the long axis of the flagellum; complete parallel alignment occurred during epididymal maturation. At spermiation spermatozoa have characteristically small cytoplasmic remnants compared to those of other macropods. Unlike the majority of macropodid spermatozoa so far described, the spermatozoa of the rufous hare wallaby showed little evidence of morphological change during epididymal transit. There was no formation of a fibre network around the midpiece or of plasma membrane specializations in this region; the only notable change was a distinctive flattening of midpiece mitochondria and scalloping of the anterior mitochondrial sheath to accommodate the sperm head. Preliminary evidence from spermiogenesis and epididymal sperm maturation supports the classification of the rufous hare wallaby as a separate genus but also indicates that its higher taxonomic position may need to be re-evaluated.

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Marsupial spermatozoa tolerate cold shock well, but differ in cryopreservation tolerance. In an attempt to explain these phenomena, the fatty acid composition of the sperm membrane from caput and cauda epididymides of the Eastern grey kangaroo, koala, and common wombat was measured and membrane sterol levels were measured in cauda epididymidal spermatozoa. While species-related differences in the levels of linolenic acid (18:3, n-6) and arachidonic acid (20:4, n-6) were observed in caput epididymal spermatozoa, these differences failed to significantly alter the ratio of unsaturated/saturated membrane fatty acids. However in cauda epididymidal spermatozoa, the ratio of unsaturated/saturated membrane fatty acids in koala and kangaroo spermatozoa was approximately 7.6 and 5.2, respectively; substantially higher than any other mammalian species so far described. Koala spermatozoal membranes had a higher ratio of unsaturated/saturated membrane fatty acids than that of wombat spermatozoa (t = 3.81; df = 4; p less than or equal to 0.02); however, there was no significant difference between wombat and kangaroo spermatozoa. The highest proportions of DHA (22:6, n-3), the predominant membrane fatty acid in cauda epididymidal spermatozoa, were found in wombat and koala spermatozoa. While species-related differences in membrane sterol levels (cholesterol and desmosterol) were observed in cauda epididymidal spermatozoa, marsupial membrane sterol levels are very low. Marsupial spermatozoal membrane analyses do not support the hypothesis that a high ratio of saturated/unsaturated membrane fatty acids and low membrane sterol levels predisposes spermatozoa to cold shock damage. Instead, cryogenic tolerance appears related to DHA levels. (C) 2004 Elsevier Inc. All rights reserved.

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Sperm ultrastructure is examined and described for the actinocyclidid nudibranchs Actinocyclus verrucosus, Hallaxa iju and Hallaxa indecora. Although general characteristics were consistent with previously described heterobranch observations, present investigations revealed ultrastructural synapomorphies for the family based on the morphology of the terminal region of the spermatozoon. In actinocyclidids, the axonemal microtubules penetrate for some distance beyond the annulus, and the annular accessory body elongates to completely seal the terminal region. Chromodoris also has an annular accessory body that completely seals the axoneme and terminal region, but it does not extend far beyond the annulus, and it is possible that these states were derived independently. Cytochemical staining confirmed that there was no glycogen present in the posterior region of the sperm for H. indecora or Chromodoris kuniei. However, representatives of other chromodoridid genera (Noumea, Risbecia) have an axoneme that penetrates through the entire annular complex, after which it is sheathed by a glycogen deposit. Similarities in the acrosomal complex support the proposed sister group relationship between the Actinocyclidae and Chromodorididae.

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The relationship between three genera considered basal in the Chromodorididae (Cadlina, Tyrinna, Cadlinella) has not yet been resolved by traditional morphological means. Here we examined the sperm ultrastructure of Tyrinna nobilis, Tyrinna evelinae, Cadlina flavomaculata and Cadlina cf. nigrobranchiata, with the expectation of finding phylogenetically informative characters. No Tyrinna or Cadlina species showed sperm similarities to Cadlinella. Both Cadlina species and Tyrinna nobilis (but not T. evelinae) exhibited coarse striations in the acrosomal pedestal. The putative fibers that occurred between the coarse striations of the pedestal are condensed into a layer in Cadlina and Tyrinna, but not in other species that also have coarse striations (Gymnodoris), and may constitute evidence for a close relationship. Tyrinna evelinae possessed fine acrosomal striations, which was shared with other Chromodorididae, Actinocyclidae and the cryptobranchs Rostanga and Aphelodoris. We also examined the sperm ultrastructure of 'Chromodoris' ambiguus, an animal which has shown molecular affinities to species of Cadlina, and not Chromodoris. The sperm of 'C'.' ambiguus did not exhibit the typical Cadlina characteristics, but also showed important differences to other investigated Chromodoris species.