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1.
Short‐term storage of semen is a useful strategy for preservation of fish spermatozoa. However, there is a significantly decrease on sperm function mainly due to oxidative stress. In this way, sodium alginate plays an important role as free radical scavenger compound. Accordingly, the aim of our study was to analyse the effect of a sodium alginate‐based extender on sperm function in the short‐term storage of salmonids semen. Samples of Salmo salar, Oncorhynchus kisutch, and Oncorhynchus mykiss were stored in Storfish® (Ext‐C) and Storfish® supplemented with sodium alginate (Ext‐A) during 10 days at 4°C. After storage, motility, viability, mitochondrial membrane potential (ΔΨmit), superoxide anion (O2?) level and DNA fragmentation (DNA Frag) were assessed. Ext‐A had positive effect in preservation of sperm motility, viability, ΔΨmit, O2? level and DNA integrity in the three species analysed compared to control samples. In Ext‐A, the spermatozoa of S. salar and O. mykiss showed significantly higher motility, viability and ΔΨmit than O. kisutch. However, O. kisutch and O. mykiss had significantly lower O2? level than S. salar, and DNA fragmentation in O. kisutch and S. salar was significantly lower than in samples of O. mykiss (p < 0.05). Dilution of salmonids semen in a sodium alginate‐based extender is effective for protecting sperm quality during 10 days of short‐term storage.  相似文献   

2.
The aims of this study were to evaluate porcine sperm vitrification in cryoloops, with and without two different cryoprotectants and assess two warming procedures. Extended (n = 3; r = 4) and raw (n = 5; r = 2) semen was diluted in media without and with cryoprotectants (4% dimethylformamide and 4% glycerol) to a final concentration of 20 × 106 spermatozoa ml?1 and vitrified using the cryoloops method. Two warming procedures were evaluated: rapid method (30 s at 37°C) and an ultra‐rapid method (7 s at 75°C, followed by 30 s at 37°C). Total motility (phase contrast), sperm viability (6‐carboxifluorescein diacetate and propidium iodide stain), membrane function (hypo‐osmotic swelling test), acrosome integrity (phase contrast), chromatin condensation (toluidine blue stain) and chromatin susceptibility to acid denaturation (acridine orange stain) were evaluated before and after vitrification and analysed using Friedman's test. In all media, the only seminal parameters that were maintained after vitrification were chromatin condensation and integrity. Vitrification of porcine spermatozoon using cryoloops, both in the presence or absence of cryoprotectants and independent of the warming procedure used, permits conservation of sperm chromatin condensation and integrity. It would be interesting to further verify this by producing porcine embryos using vitrified spermatozoon with intracytoplasmic sperm injection.  相似文献   

3.
Sperm vitrification is a cryopreservation method based on high‐speed freezing by direct exposure of cells in liquid nitrogen (N2L), thereby avoiding the traditional cooling curves of freezing. The objective of this work was to determine the optimal warming temperature for vitrified human spermatozoa in order to maintain their fertilisation potential. Spermatozoa were cryopreserved by direct plunging into N2L and warmed at different temperatures for 5 and 10 s at 38, 40 and 42 °C. Sperm motility was evaluated by the CASA system and the sperm membrane function by HOST test. It was detected that progressive motility of sperm warmed at 38, 40 and 42 °C was 26.4 ± 8.4%; 56.6 ± 16.3% and 65.4 ± 15%, respectively, with statistically significant differences between the temperatures of 38 and 40 °C and 38 and 42 °C (P < 0.05). The plasma membrane function evaluated by HOST test was better preserved at 42 °C (76.3 ± 2.0%) compared to 40 °C (43 ± 2%) and 38 °C (65.6 ± 1.5%). The temperature in the thawing process can affect the motility and plasma membrane integrity and function. The warming at 42 °C for thawed vitrified sperm is the optimum temperature to preserve the sperm physiological parameters.  相似文献   

4.
There are many protocols for horse sperm cryopreservation, but results are inconsistent; sperm survival after freeze‐thawing is usually poor; in consequence, fertility is low. The objective of this work was to see whether slow cooling before freezing to minus 3 °C instead of +5 °C, the traditional target temperature, could improve horse sperm cryosurvival, capability to carry out capacitation and the acrosome reaction induced by progesterone. Spermatozoa from five stallions were packaged in straws and slowly cooled to +5 °C. Half of the straws were frozen directly and the other half was further cooled to ?3 °C before freezing. Progressive motility, viability, plasma membrane integrity, acrosome integrity and capacitation status were assessed. After thawing, there were no differences between cooling treatments on motility, viability, acrosome integrity and capacitation status; however, there was difference (P < 0.05) regarding plasma membrane integrity. Acrosome integrity decreased as incubation, without or with progesterone (2 μg ml?1), progressed, but there were no differences between cooling treatments regardless of progesterone. Both capacitated and acrosome‐reacted spermatozoa increased as incubation progressed, but there were no differences between cooling treatments regardless of progesterone. Slow cooling to ?3 °C before freezing did not improve horse sperm cryosurvival or capability to undergo the acrosome reaction.  相似文献   

5.
This study was conducted to investigate the effect of l ‐arginine addition on long‐term storability of ram semen. Six Akkaraman rams were used as material. Semen samples were collected. Pooled samples were diluted and were divided into six equal aliquots. While aliquot 1 was kept as control, the stock solutions including 0.1, 0.5, 1, 5 and 10 mm l ‐arginine were added to other aliquots. All aliquots were routinely frozen in 0.25‐ml straws at ?130°C liquid nitrogen vapour and stored in liquid nitrogen ?196°C until being analysed. The equilibrated and thawed sperm motility, membrane integrity and arginase activity were evaluated. While the 10 mm l ‐arginine supplementation significantly (< .001) decreased equilibrated sperm motility, the 5 mm significantly (< .05) increased the membrane integrity and arginase activity in comparison with the control group. The motility (< .001) and membrane integrity (< .01) were determined to be highest in 0.5 mm group, while significant reductions were observed in motility (< .001) of 10 mm group and arginase activity (< .05) of 1, 10 mm groups as compared to the control group. It was concluded that in vitro addition of 0.5 mm l ‐arginine to ram semen may be useful, but 10 mm may be harmful to spermatozoa quality during long‐term storage.  相似文献   

6.
The ability of sucrose to protect spermatozoa against mitochondrial damage, artificial acrosome reaction and DNA fragmentation during ultra‐rapid cryopreservation in canine sperm was investigated. Swim‐up selected spermatozoa of second‐fraction semen were vitrified with different concentrations of sucrose (0.1, 0.25 and 0.4 m ) in proportion 1 : 1 v/v with HTF–BSA 1%. From each group, 30‐μl suspensions of cells were dropped directly into liquid nitrogen and stored for at least 24 h. Cells were thawed by submerging the spheres in HTF with 1% BSA at 37 °C. The number of progressively motile spermatozoa was significantly higher in the sucrose 0.25 m + HTF–BSA 1% (42.5 ± 2.3%, P < 0.01) than in HTF only (1.66 ± 0.3%). The same combination of sucrose 0.25 m + HTF–BSA 1% (42.7 ± 1.5%) had a stronger cryoprotective effect on the integrity of mitochondrial membrane potential (P < 0.05) and decreased the DNA fragmentation (2.8 ± 0.5%) as compared with HTF only (1.93 ± 0.6% and 5.6 ± 0.6% respectively). With respect to acrosome‐reacted spermatozoa, no significant difference was found between the groups investigated (P > 0.05). It is concluded that sucrose, a nonpermeable cryoprotectant, can effectively preserve important physiological parameters such as mitochondrial membrane potential and DNA integrity during ultra‐rapid cryopreservation.  相似文献   

7.
We focussed on evaluating the protective effect of lycopene and resveratrol on post‐thaw bull sperm and oxidative stress parameters. Nine ejaculates for each bull were used in the study. Each ejaculate, splitted into three equal aliquots and diluted at 37 °C with base extenders containing lycopene (1 × 10?3 g ml?1) and resveratrol (1 mm ), and no antioxidant (control), was cooled to 5 °C and then frozen. Frozen straws were thawed in a water bath for evaluation. The supplementation of the semen extender with lycopene and resveratrol increased the percentages of post‐thawed computer‐assisted sperm analysis (CASA) motility (55.8 ± 3.8 and 61.9 ± 4.0%) and progressive motility (38 ± 2.4 and 37 ± 8.8), compared with the controls (50.7 ± 2.65 and 33.3 ± 3.74%, respectively, P < 0.05). Resveratrol provided a higher ALH (4.3 ± 0.1), in comparison with the control (3.9 ± 0.3, P < 0.05). The supplementation of the semen extender with lycopene and resveratrol produced a higher mitochondrial activity (24.6 ± 2.9 and 30.1 ± 6.5% respectively), compared with that of the control (11.8 ± 9.5%, P < 0.05). It was determined that both antioxidants resulted in a lower percentage of sperm with damaged DNA than that of the control (P < 0.05). Sperm motion characteristics except for ALH, acrosome integrity, sperm viability and oxidative stress parameters were not affected by the adding of lycopene and resveratrol.  相似文献   

8.
The effects of freezing methods (FR1, nonprogrammable/static, 5 cm above liquid nitrogen [LN2] for 10 min, plunging in LN2; FR2, programmable medium, +4°C to ?15°C at 3°C min?1, from ?15 to ?80°C at 10°C min?1 and final holding for 1 min at ?80°C, plunging in LN2; FR3, programmable fast, from initial holding at +4°C for 2 min, from +4°C to ?20°C at 10°C min?1, from ?20°C to ?100°C at 30°C min?1, final holding for 1 min at ?100°C and plunging in LN2) were assessed on post‐thaw in vitro quality and in vivo fertility of water buffalo spermatozoa. Mean sperm progressive motility (%), rapid velocity (%), average path velocity (μm s?1), straight line velocity (μm s?1), curved line velocity (μm s?1), integrities (%) of plasmalemma, mitochondrial transmembrane, DNA and acrosome were higher (< .05) in samples cryopreserved with FR3 compared to FR1 and FR2. Similarly, in vivo fertility (%) of buffalo spermatozoa was higher (< .05) with FR3 than FR1 (%; 68.0 versus 50.0). We concluded that programmable fast‐freezing method (FR3) improves the post‐thaw in vitro quality and in vivo fertility of water buffalo spermatozoa.  相似文献   

9.
The potential protective effect of catalase supplementation during in vitro culture of frozen/thawed bull spermatozoa was investigated. Frozen/thawed semen collected from three fighting bulls was diluted in phosphate buffered saline (PBS) and incubated at 37 °C under different experimental conditions: Control, Catalase (CAT) (200 U/mL), Oxidant (OXI) (100 μ m Fe2+/1 m m ascorbate), and Catalase + Oxidant (CAT/OXI). We assessed sperm motility, acrosomal integrity, viability and chromatin status (SCSA®) at 0, 2 and 6 h of incubation. Our results showed that catalase abolished the effect of the oxidant, protecting spermatozoa against reactive oxygen species, and improving both sperm motility and chromatin status during incubation. The OXI treatment significantly reduced the percentage of motile sperm after 6 h of incubation. The statistical model also showed that there were differences in sperm motility between CAT/OXI (20.8 ± 2.9%) and OXI (11.6 ± 7.6%) ( p  < 0.001). There were no significant effects of OXI on sperm viability, acrosomal status or proportion of abnormal tails. %DFI (spermatozoa with moderate or high DNA Fragmentation Index) was significantly higher on OXI ( p  < 0.001). Catalase prevented DNA fragmentation even in the presence of the oxidant (%DFI: 30.3 ± 0.8% OXI vs. 17.4 ± 0.7% CAT/OXI). We conclude that catalase supplementation after thawing could protect bull spermatozoa against oxidative stress, and it could improve media used for processing thawed spermatozoa.  相似文献   

10.
Owing to current problems in boar sperm cryopreservation, this study proposes to evaluate vitrification in spheres as an alternative cryopreservation procedure, comparing the use or not of permeable cryoprotectants and two warming methods. Extended (n = 3; r = 4) and raw (n = 5; r = 2) porcine spermatozoa were diluted in media, in the absence or presence of either 4% dimethylformamide or 4% glycerol, to a final concentration of 5 × 106 spermatozoa/ml and vitrified using the spheres method. Two warming procedures were evaluated: a rapid method (30 s at 37°C) and an ultrarapid method (7 s at 75°C, followed by 30 s at 37°C). Percentages of total motility (phase contrast), membrane function (hypo‐osmotic swelling test), acrosome integrity (phase contrast), sperm viability (6‐carboxyfluorescein diacetate and propidium iodide stain), chromatin condensation (toluidine blue stain) and chromatin susceptibility to acid denaturation (acridine orange stain) were evaluated in the samples before and after vitrification. Results, analysed using Friedman's test, suggest that rapid warming of raw porcine spermatozoa vitrified without permeable cryoprotectants may preserve DNA condensation and integrity better than the other processing methods studied in this work. Hence, porcine sperm vitrification using spheres could be used to produce embryos with ICSI to further validate this method.  相似文献   

11.
Sperm DNA damage, excessive oxidative stress and decrease in motility ?may lead to low fertilisation or poor? assisted reproductive techniques outcomes in asthenoteratozoospermic ?men. Selenium was considered as essential element for male reproductive functions. Selenium has important role in enzymatic process for elimination of excessive reactive oxygen species and helps to maintain membrane integrity. The aim of this study was to determine the effect of selenium supplementation on sperm quality, DNA fragmentation, mitochondrial membrane potential and membrane lipid peroxidation during sperm sampling in vitro at different times. In this experimental study, semen samples were collected from 50 asthenoteratozoospermic men. Samples were divided into two groups as control group and test group (incubated with 2 μg/ml selenium at 37°C for 2, 4 and 6 hr). Motility and viability were assessed based on WHO 2010 criteria. Mitochondrial membrane potential, sperm DNA fragmentation and malondialdehyde levels were evaluated in each group. Results revealed that motility, viability and mitochondrial membrane potential were significantly higher in the test group (p < .05). Also malondialdehyde levels were significantly lower in the test group (p < .03). DNA fragmentation significantly decreased in the test group after 6 hr of incubation (p < .02). In conclusion, in vitro selenium supplementation may protect spermatozoa from maltreatment effect of reactive oxygen species (ROS) during sperm sampling via keeping enzymatic and antioxidant process in optimum condition.  相似文献   

12.
The aim of this study was to assess the stability of nuclear and mitochondrial DNA (n‐DNA and mt‐DNA) of spermatozoa under freeze‐thawing and to find out the correlation between them and their association with standard sperm parameters. Forty‐three semen samples were collected from fertile (G.1; n = 29) and sub‐fertile (G.2; n = 14). N‐DNA fragmentation was determined by TUNEL assay and mt‐DNA using caspase 3 staining. Each semen sample was frozen at ?196°C by the programmed freezer. Freeze‐thawing decrease vitality, total motility and membrane integrity from (43.02 ± 22.74%; 31.63 ± 18.15%; 51.5 ± 24.82%) to (22.71 ± 17.3%; 9.21 ± 6.61%; 34.64 ± 19.92% respectively [p < .001]). G.1 native spermatozoa stained positive with TUNEL and caspase 3 were (14.85 ± 17.6% and 5.8 ± 11.59%) and increased after freeze‐thawing to 27.54 ± 19.74% (p = .004) and 7.3 ± 6.13% (p = .01) respectively. In G.2, TUNEL and caspase 3 were (19.84 ± 17.52% and 7.53 ± 8.56%) and increased to (29.48 ± 16.97% [p = .03] and 10.21 ± 11.73%). In conclusion, freeze‐thawing process affects not only semen parameters but also n‐DNA and mt‐DNA. Therefore, n‐DNA and mt‐DNA could be used as sensitive parameters for assessment of the cryodamage of human spermatozoa.  相似文献   

13.
The knowledge of sperm quality in the broodstock males of different ages is a prerequisite to identify the reproductive ability of cultivated fish for the hatchery management. Thus, in this work, we analysed sperm function of the semen stored of broodstock males of rainbow trout (Oncorhychus mykiss) in different reproductive ages (2, 3 and 4 years old). Sperm samples of each reproductive age were stored in Storfish® during 10 days at 4°C, and then, motility, viability, mitochondrial function (MMP), superoxide anion () level and DNA fragmentation (DNAfrag) were assessed. The results demonstrated that sperm function parameters were affected significantly by the age of the males and the time of storage. Motility, viability and MMP significantly decreased, and DNAfrag and level increased with the age increment and the time of storage. In conclusion, sperm quality of 2 and 3 years old were superior to those of 4 years old, based on higher quality of various sperm functions such as motility, viability, MMP, DNA integrity and level during short‐term storage. This information must be considered for optimum utilization of broodstock males in aquaculture.  相似文献   

14.
Due to homologies between the chicken egg perivitelline membrane with mammalian zona pellucida proteins, spermatozoa of several species are able to bind to this membrane. However, adequate standardisation is required to attest possible applications of this technique for semen evaluation of a given species. Therefore, we thawed and divided cryopreserved semen samples into two aliquotes, one kept in water bath at 37 °C (thawed) and the other submitted to snap‐freezing to damage sperm cells (dead spermatozoa). Aliquotes were mixed into different ratios of thawed:dead cells and analysed for motility, membrane and acrosomal integrity, and mitochondrial activity. In parallel, chicken egg perivitelline membranes were inseminated with these ratios, and the number of spermatozoa bound per mm2 of membrane was assessed by conventional microscopy (CM) and computer‐assisted sperm analysis (CASA). Linear regression showed high correlation between thawed:dead sperm ratio and number of spermatozoa bound to the membrane (CM: r2 = 0.91 and CASA: r2 = 0.92 respectively). Additionally, positive correlations were found between the number of spermatozoa bound to the membrane and acrosomal integrity, membrane integrity, mitochondrial activity and motility. These findings indicate that sperm‐egg‐binding assay associated with CASA is a reliable, practical and inexpensive method for examining the fertilising capacity of cryopreserved bull semen.  相似文献   

15.
Reports indicate an increase in the incidence of DNA fragmentation in male factor infertility and its role in the outcome of assisted reproductive techniques (ART). However, reports are conflicting between the relationships of sperm DNA integrity with conventional semen parameters. We examined the relationship between conventional sperm parameters and DNA integrity using acridine orange (AO) test. The study included 373 patients and 28 fertile volunteers. DNA normality was compared with semen parameters between the patient and donor populations. Significant correlations were noted between DNA normality and sperm concentration ( r  = 0.18, P  = 0.000), motility ( r =  0.21, P  = 0.0001), rapid motility (0.19, P  = 0.000), normal morphology by World Health Organization ( r =  0.15, P  = 0.019) and head defects ( r =  −0.15, P  = 0.023). A significant difference was noted in AO levels between donors and patients with asthenozoospermia ( P  = 0.002) and oligoasthenozoospermia ( P  = 0.001). A significant difference in DNA integrity was noted in samples having <30% and >30% normal morphology. A wide range of % DNA normality was observed in the patient group. Sperm assessment for DNA status using AO is reliable and shows good correlation with sperm count, motility and morphology. Assessment of sperm DNA status with AO staining may be helpful prior to ART.  相似文献   

16.
The aim of the present study was to evaluate the degree of sperm DNA fragmentation in couples with idiopathic recurrent spontaneous abortion (RSA) and in those with no history of infertility or abortion. In this cohort study, 30 couples with RSA and 30 fertile couples as control group completed the demographic data questionnaires, and their semen samples were analysed according to World Health Organization (WHO) standards (September 2009–March 2010) for evaluation of sperm DNA fragmentation, using sperm chromatin dispersion (SCD) technique. The percentage of morphologically normal sperm was significantly lower in RSA patients compared with control group (51.50 ± 11.60 versus 58.00 ± 9.05, P = 0.019), but not in other parameters. Additionally, the level of abnormal DNA fragmentation in the RSA group was significantly higher than in the control group (43.3% versus 16.7%, P = 0.024). Our results indicated a negative correlation between the number of sperm with progressive motility and DNA fragmentation (r = ?0.613; P < 0.001). The sperm from men with a history of RSA had a higher incidence of DNA fragmentation and poor motility than those of the control group, indicating a possible relationship between idiopathic RSA and DNA fragmentation.  相似文献   

17.
The aim of this study was to compare the sperm separation technique using filtration through glass wool compared with just diluted cooled semen. Eighteen ejaculates were collected from 6 pony stallions of the Brazilian pony breed. Evaluations were done on pH, osmolarity, total motility, membrane functionality (HOST), membrane integrity (CFDA/PI), morphology and mitochondrial viability (MTT) in fresh, 24 and 48 h of cooled semen at 5°C. After dilution, the half of the extended semen was cooled (control group). The other half was cooled after filtration trough glass wool (filtered group). Retained semen was considered the portion of cells that did not transpose glass wool barrier. Total motility from the control, filtered and retained groups after 24 h of cooling was 35.5%, 43.3% and 10% (p < .0001) respectively. Sperm membrane integrity percentage at the CFDA/PI test was 37.9%, 44.8% and 14.8% (p < .0001), on the control, filtered and retained groups respectively. The results confirmed that the passage of spermatozoa through glass wool increased the selection of spermatozoa from pony stallions with higher motility, mitochondrial viability and membrane integrity for cooling in milk extender up to 24 h. Moreover, it was not obtained higher sperm parameters to control after cooling 48 h under the conditions that the study was conducted.  相似文献   

18.
The short‐term storage of salmonid semen is a viable method for in vitro fertilisation. Previous studies have found that short‐term storage affects sperm motility, compromising quality and fertilising capacity. However, the functional characteristics of the spermatozoa of O. mykiss during storage time and its relation to the spawning period are little known. This study was designed to evaluate the effects of in vitro short‐term storage on sperm functional parameters in O. mykiss, determined by flow cytometry. Semen samples of the first spawning – undiluted (SSD) and diluted (SD) (Storfish® 1 : 2v/v; IMV AI solutions, France) – were stored at 4 °C for 14 days. Motility, viability (PMI: plasma membrane integrity) and mitochondrial membrane potential (ΔΨM) were assessed. On the fifth day of storage, spermatozoa showed a motility >70% (SSD: 78.3% versus SD 85.0%), PMI (81.5% SSD/87.2% SD) and ΔΨM (72.5% SSD/SD 80.0%) (P < 0.05). However, a significant decline in the percentage of all functional parameters (P < 0.05) was observed after 5 days of storage for all samples of both undiluted (SSD) and diluted semen. In conclusion, the results here provide new data on O. mykiss sperm quality with respect to in vitro short‐term storage evaluated by flow cytometry.  相似文献   

19.
The aim of this study was to evaluate motility, viability, DNA integrity and apoptosis of spermatozoa when washed semen samples were kept for up to 12 days at 4–6°C and 25°C. In this experimental study, 26 normozoospermic semen samples were washed twice in Modified Ham's F10 and resuspended in IVF fertilisation medium. Half of the specimens were stored at 4–6°C, and the other half was kept at 25°C for 12 days. The proportions of viable, motile, spermatozoa with double-stranded DNA and apoptotic spermatozoa were examined during storage time. Apoptosis was measured using annexin V-PI staining followed by flow cytometry. Results showed that sperm motility and viability decreased during 12 days of sample storage (p < .001). There was no significant difference between the two temperatures in terms of motility and viability for up to 2 days (p < .05). The percentage of spermatozoa with double-stranded DNA remained unchanged during the 12 days of storage at both temperatures (> .05). Although there was no difference between the two temperatures in terms of motility, viability and apoptosis during the first two days of storage, storage of spermatozoa at 4–6°C is better than storage for a longer period than storage at 25°C. Sperm DNA resisted against denaturation during storage.  相似文献   

20.
目的:探讨可以全面有效评估捐精者生育力的精子功能指标,运用于复苏精液标本的筛选,旨在提高辅助生殖技术成功率。方法:根据捐精者精液使用的妊娠结局,收集上海市人类精子库高、低生育力捐精者的冷冻精液标本各20例,比较两组精液标本复苏后的精子浓度、活力、正常形态率、顶体完整率、DNA完整性以及线粒体膜电位。结果:高、低生育力组精液复苏经系列评估后,正常形态率分别为(18.50±6.10)%、(14.42±6.44)%;顶体完整率分别为(86.17±4.49)%、(80.04±7.52)%;精子DNA碎片率分别为(9.21±3.22)%、(15.72±8.20)%,以上指标经统计学分析两组之间具有显著性差异(P0.05)。但线粒体膜电位高生育力组[(56.75±18.80)%]与低生育力组[(52.23±18.86)%]之间无显著性差异(P0.05)。精子线粒体膜电位与精子活力呈显著正相关(r=0.760,P0.05),其他功能指标与精子浓度、活力无显著相关。结论:精子浓度、活力与正常形态率、顶体完整率以及DNA完整性可以有效评估捐精者复苏精液生育能力。  相似文献   

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