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21.
Sperm cell defense against DNA damage relies on two factors: the tight packaging of chromatin, based on condensation and substitution of histones with protamines, and the antioxidant agents present in seminal plasma. These defenses are extremely important as mature sperm is unable to repair DNA damage and even if a successful fertilization occurs, embryo undergoes apoptosis at the time of genomic activation. Sex-sorting exposes spermatozoa to stress sources such as high pressure, laser beam and electrical charge. The aim of this work was to determine how sorting procedures affect viability and DNA integrity in boar spermatozoa, by using the newly developed Sperm-Sus-Halomax. Four sperm populations were considered: CONTROL (no treatment), REAL (sex-sorted semen), BULK (semen sorted without sex separation) and NO LASER (semen only exposed to the high pressure, but including also cells normally discarded from sex-sorting). A significantly (P=0.019) lower viability in NO LASER (64.71%) than in CONTROL (78.6%) and REAL (80.5%) groups was found; this was accompanied by a significantly (P=0.001) higher DNA fragmentation index (DFI) in NO LASER group (6.86%) respect to CONTROL (3.30%) and REAL (3.42%) groups. BULK group did not show any difference in viability or DFI as compared to the other groups. In conclusion, we may believe that sex-sorting procedure as a whole does not affect either viability or DFI and that shear mechanical forces are a relevant source of DNA damage for sorted semen.  相似文献   
22.
Brucella ovis was isolated for the first time in Italy in 1994 from the genital organs of two domestic rams. In subsequent years bacteriologic and serologic investigations demonstrated an increasing distribution of this disease in domestic sheep. Mouflon (Ovis musimon) occur in several hilly and mountainous areas of Italy where they can potentially contact domestic sheep. To determine if this species may have a role in the epidemiology of B. ovis, four male and four female mouflon, serologically negative for B. ovis and other Brucella spp., were infected intra-conjunctivally with B. ovis strain BG1/94. Physical examinations, including collection of blood samples for serology and bacteriology, were performed weekly. The animals were euthanized 8 mo postinoculation (p.i.). Samples of retropharyngeal, parotid, and iliac lymph nodes; bone marrow; kidneys; spleen; epididymis; testicle; bulbourethral glands; seminal vesicles; uterus; and oviducts were collected from each animal as appropriate for histopathology and bacteriology. At the time of euthanasia none of the animals exhibited obvious clinical signs of brucellosis. The animals seroconverted 2 wk p.i. and became seronegative 24 wk p.i. Bacterial cultures, including hemocultures, were negative. No lesions due to B. ovis infection were revealed by histologic examinations. Brucella ovis probably did not infect mouflon and this wild sheep is not likely to play a role in the epidemiology of contagious epididymitis caused by B. ovis.  相似文献   
23.
In Brazil, the epicenter of the Zika crisis, brown, black, and indigenous poor women living in municipalities with scarce resources were disproportionally affected. The gendered consequences of the epidemic exposed how intersectional lenses are central to understand the impact of public health emergencies in the lives of women and girls. The demand for Zika-affected children and women to be research participants is relevant for an ethical analysis of participant protection procedures during a crisis. We investigated how women experienced research participation by analyzing their narratives. Two-year-long longitudinal qualitative study in Brazilian sites located in the epidemic's epicenter was performed using mixed methods: ethnography with women from two distinct states and individual semi-structured interviews with five women in different Zika-affected states, four of which were community leaders. All women in the study were mothers or grandmothers of Zika-affected children. Thematic analysis was used for data evaluation. Women perceived being pressured to participate in research and a lack of benefit sharing. Structural determinants of gender inequality, such as its effect on power distribution, were found to impact research participant protection. Formal procedures for research protocols approvals were insufficient in protecting participants because these instruments were unable to account for structural aspects. Communitarian mobilization, through WhatsApp groups, was found to be an important mechanism to create conditions to challenge oppressive structures. Strengthening public health, effective community-based participation in research planning and implantation of ethical strategies that promotes gender equality can have transformative effect on unequal power structures and promote participant protection.  相似文献   
24.
25.
Many non-indigenous species have been found during recent decades in the Lagoon of Venice; many of these species are rapidly becoming both widespread and abundant. Reported here is the invasion of an accidentally introduced bryozoan Tricellaria inopinata, which dominated the Lagoon's fouling community within seven years of its initial detection. Recent declines in its population as well as those of indigenous bryozoans illustrate the importance of placing invasions in the context of the hydrological, chemical and biotic changes that occur in the Lagoon environment. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
26.
Upon damage by herbivores, plants induce an array of volatile organic compounds (VOCs) that mediate ecological interactions involving communication with organisms of the second and third trophic levels. VOC-mediated tritrophic interactions have largely been studied in various systems, including cassava (Manihot esculenta), but little is known about the chemical nature of herbivore-induced VOCs in this crop and the response they evoke in natural enemies. Several tetranychid and predatory mites are associated with cassava. Here, VOC emissions from uninfested plants and plants infested with 200 or 400 Mononychellus tanajoa, a specialist herbivore on cassava, and the generalists Tetranychus urticae and T. gloveri were measured. Dual-choice experiments were also conducted to assess the preference of inexperienced (reared on prey-infested bean plants) and experienced (adapted on prey-infested cassava plants) predatory mites, Neoseiulus idaeus (Phytoseiidae), between odors of uninfested plants versus odors of plants infested with M. tanajoa, T. urticae or T. gloveri. Two hundred individuals significantly increased the emissions of (Z)-3-hexen-1-ol, (E)-β-ocimene, β-caryophyllene, alloaromadendrene and (E)-geranyl acetone in T. urticae-infested plants, and (E)-β-ocimene and methyl salicylate (MeSA) in T. gloveri-infested plants. Four hundred individuals significantly increased the emissions of (Z)-3-hexen-1-ol, MeSA, α-pinene and D-limonene in M. tanajoa-infested plants. In addition, T. urticae at this density induced (E)-β-ocimene, D-limonene, (E)-geranyl acetone and six compounds that were not detected in other treatments. Tetranychus gloveri-infested plants induced the emissions of (E)-2-hexenal and D-limonene. Regardless of the infesting species, inexperienced N. idaeus did not discriminate between uninfested or infested plants. Upon experience, they discriminated between the odors of uninfested and T. urticae-damaged plants. Our findings reveal that mite infestations in cassava result in density-dependent and species-specific emission of VOCs, and that N. idaeus relies on associative learning to forage for its prey.  相似文献   
27.
Changes in the signaling effort of virgin females are known to occur until their first mating. Young females tend to increase the calling effort (number and time duration of bouts) as they age. In this context, the calling behavior of virgin females of Atheloca subrufella, an important pest of coconut palms (Cocos nucifera), was studied under laboratory conditions. Thirty four virgin females were observed during 16 scotophases (25 ± 2 °C, 75 ± 5 % RH and 10 h scotophase), until they stopped calling in the following photophase. The calling position, pattern and frequency were evaluated. Females of A. subrufella showed only one calling position, and calling peaked between the second and fifth scotophases. Most females did not start calling immediately after emergence. Neither the individual duration of calling nor the number of calling bouts changed over time. However, the time that calling started was earlier in older females, probably to avoid competition with younger females and increase the probability of mating. These data support the hypothesis that there is an age-dependent pattern of pheromone emission in virgin females of A. subrufella.  相似文献   
28.
The aim of this work was the design of sustained-release mucoadhesive bilayered tablets, using mixtures of mucoadhesive polymers and an inorganic matrix (hydrotalcite), for the topical administration of flurbiprofen in the oral cavity. The first layer, responsible for the tablet retention on the mucosa, was prepared by compression of a cellulose derivative and polyacrylic derivative blend. The second layer, responsible for buccal drug delivery, was obtained by compression of a mixture of the same (first layer) mucoadhesive polymers and hydrotalcite containing flurbiprofen. Nonmedicated tablets were evaluated in terms of swelling, mucosal adhesion, and organoleptic characteristics; in vitro and in vivo release studies of flurbiprofen-loaded tablets were performed as well. The best results were obtained from the tablets containing 20 mg of flurbiprofen, which allowed a good anti-inflammatory sustained release in the buccal cavity for 12 hours, ensuring efficacious salivary concentrations, and led to no irritation. This mucoadhesive formulation offers many advantages over buccal lozenges because it allows for reduction in daily administrations and daily drug dosage and is suitable for the treatment of irritation, pain, and discomfort associated with gingivitis, sore throats, laryngopharyngitis, cold, and periodontal surgery. Moreover, it adheres well to the gum and is simple to apply, which means that patient compliance is improved. Published: July 13, 2007  相似文献   
29.
The beneficial properties of green tea and especially of its principal active polyphenol, epigallocatechin-3-gallate (EGCG), have led to an increased demand for dietary supplements with highly enriched EGCG concentrations. In order to investigate the possible reproductive-related consequence of EGCG supplementation, the effects of this catechin on in vitro maturation (IVM) and fertilization (IVF) of oocyte, using the pig as experimental model, were examined. In the first series of experiments EGCG, at concentrations ranging from 0 to 25 microg/ml, was added during in vitro maturation of pig oocytes. EGCG had no effect on nuclear maturation of pig oocytes and on fertilization traits considered after IVF at any of the doses tested. By contrast, a significant (p<0.05) decrease in the number of embryos that developed to blastocysts following parthenogenetic activation was recorded when 25 microg/ml EGCG was added to IVM medium; in addition this catechin concentration significantly (p<0.05) inhibited progesterone production by cumulus cells after 48 h of culture. When induction of sperm capacitation was performed in presence of EGCG, a significantly lower percentage of spermatozoa showing a Hsp70-capacitated pattern and a significant reduction of sperm H(2)O(2) production were evident at a concentration of 25 microg/ml EGCG (p<0.05). During gamete coincubation EGCG reduced, in a dose response manner, the number of reacted spermatozoa suspended in fertilization medium and increased the number of sperm bound to ZP. Supplementation of 10 microg/ml EGCG during IVF significantly increased the fertilization rate while higher EGCG concentrations (25 microg/ml) decreased the percentage of fertilized oocytes (p<0.05). In conclusion, our data suggest that high EGCG concentrations could affect in vitro maturation and fertilization in pig; it cannot be totally excluded that excessive EGCG concentrations could induce reproductive-related consequences also in vivo.  相似文献   
30.
Artificial breeding bypasses the effect of natural selection and, inevitably, subjects game birds to selection by breeding technology. For this reason, we evaluated whether different breeding technologies, carried out for six generations, were enough to differentiate two grey partridge lines. Two lines of grey partridges, obtained from the same population, were used: the animals of the line broody had been hatched directly by their own mothers for six generations; the animals of the line incubator had always been hatched in incubators from eggs laid by cage-reared grey partridges. Offspring from the two lines were reared under the same conditions and 2 years of production were monitored. Results showed that grey partridges of the broody line had a shorter and delayed laying period and, consequently, a lower egg production than the incubator line. In the first year of production, mean length of laying period 58 vs. 75 days, p<0.01; mean start of egg production through photostimulation: 61 vs. 42 days, p<0.01; mean number of eggs laid: 46 vs. 58, p<0.01. In the second year: mean length of laying period, 63 vs. 66 days, p<0.05; mean start of first egg production through photostimulation: 51 vs. 45 days, p<0.05; mean number of eggs laid: 45 vs. 56, p<0.01.  相似文献   
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