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1.
2.
This study investigated the role of vitamin C as an antioxidant in protecting the testis against damage in experimental unilateral cryptorchidism. Forty‐five male Wistar Albino rats were divided into three groups. The control group had intact rats, the cryptorchid group had unilateral cryptorchid rats and the treatment group had unilateral cryptorchid rats that it received vitamin C at a dose of 50 mg kg?1 body weight intraperitoneal, once a day, during experimental period. Histopathological samples were obtained from five cases of 15 animals of each group at 15, 30 and 60 days after induction of cryptorchidism. The results showed histopathological parameters of the cryptorchid (left) testes in the cryptorchid group significantly decreased compared with the control group (P < 0.05), and treatment with vitamin C after 60 days significantly improved all parameters of these testes compared with the cryptorchid group (P < 0.05). In addition, the left testes on unilateral cryptorchid rats had noticeable adverse effects on the scrotal (right) testes (P < 0.05). Treatment with vitamin C after 60 days significantly improved all parameters of these testes compared with the cryptorchid group (P < 0.05). It can be concluded that treatment with vitamin C significantly improved histopathological parameters in scrotal testes on unilateral cryptorchid rats.  相似文献   

3.
Exposure to either environmental toxicants or chronic hyperglycaemia could impair male reproductive function. However, the extent to which exposure to such toxicants, in the presence of pre‐existing metabolic dysfunction, could affect male reproduction is unclear. Streptozotocin‐induced diabetic Wistar rats (12 weeks old) were exposed to oral aluminium chloride at 250 ppm for 30 days; followed by evaluation of caudal epididymal sperm count and motility, assay for serum follicle stimulating hormone (FSH), testosterone (T) and oestradiol; and assessment of testicular histology. Moreover, blood glucose was evaluated by the glucose oxidase method. In rats treated with streptozotocin (STZ) or aluminium (Al) alone, erosion of testicular parenchyma and stroma was observed. This effect was most severe in diabetic rats simultaneously exposed to Al; coupled with reduced caudal epididymal sperm count that was least in this (STZ+Al) group (18.75 × 106 ml?1) compared with controls (61.25 × 106 ml?1; P < 0.05), STZ group or Al group. Moreover, these reproductive perturbations (in the STZ+Al group) were associated with reduced sperm motility and significantly reduced serum FSH (P < 0.05); but elevated serum T and oestradiol (P < 0.05), compared with control. These suggest that diabetes‐induced testicular lesion is exacerbated by simultaneous oral Al toxicity in Wistar rats.  相似文献   

4.
In this study, solitary and combined effects of vitamin E and the calcium‐channel blocker diltiazem were investigated in streptozotocin (STZ)‐induced diabetic rats. Thirty male Wistar albino rats, weighing approximately 200 g were used. Diabetes mellitus was induced by a single intravenous injection of STZ at a dose of 65 mg/kg body weight. Five experimental groups were established as STZ‐diabetic, STZ‐diabetic + vitamin E, STZ‐diabetic + diltiazem and STZ‐diabetic + vitamin E + diltiazem. Vitamin E was injected intraperitoneally three times a week at a dose of 500 mg/kg body weight. Diltiazem was given orally every day at a dose of 25 mg/kg body weight. At the end of the study (10 weeks) blood glucose levels of diabetic rats, which had received vitamin E and diltiazem, had significantly decreased when compared with untreated diabetic rats (P < 0.02). Similarly, HbA1c levels had significantly decreased in diabetic rats which had received vitamin E (P < 0.05), diltiazem (P < 0.01) and vitamin E + diltiazem (P < 0.02) when compared with untreated diabetic rats. Liver glutathione levels of diabetic rats, which had received vitamin E (P < 0.01) and vitamin E + diltiazem (P < 0.05) had significantly increased when compared with untreated diabetic rats. Liver lipid peroxide levels had significantly decreased in diabetic rats, which had received vitamin E (P < 0.001) and diltiazem (P < 0.01). With respect to their metabolic and antioxidant effects, vitamin E proved superior to diltiazem.  相似文献   

5.
This study was conducted to compare the effects of administration of coconut oil (CO) and Moringa oleifera oil (MO) on testicular oxidative stress, sperm quality and steroidogenesis parameters in rats treated with mercury chloride (HgCl2). After 15 days of oral administration of CO (2 ml kg?1 body weight) and MO (2 ml kg?1 body weight) along with intraperitoneal (i.p.) administration of HgCl2 (5 mg kg?1 body weight) alone or in combination, we found that CO treatment did not protect against HgCl2‐induced poor sperm quality (motility, count) as well as decreased testosterone level and 17β‐hydroxysteroid dehydrogenase (17β‐HSD) activity. Treatment with CO alone decreased glutathione (GSH), and glutathione peroxidase (GSH‐Px) activities and increased malondialdehyde (MDA) level in rat's testis, whereas MO did not change these parameters. Cotreatment with MO prevented HgCl2‐induced testicular catalase (CAT) and superoxide dismutase (SOD) activities, poor sperm quality and low testosterone level and also blocks the adverse effect of CO+HgCl2 (2 ml kg?1 body weight + 5 mg kg?1 body weight) on the investigated endpoints. In conclusion, MO and not CO decreased the deleterious effects of HgCl2 on sperm quality and steroidogenesis in rats and also strengthen the antioxidant defence of the testes. Therefore, MO is beneficial as an antioxidant in HgCl2‐induced oxidative damage.  相似文献   

6.
Cinnamon and its contents have multifactorial properties such as antioxidant, anti‐inflammatory and antidiabetic. Male infertility is one of the major health problems in life. The aim of this study was to investigate the effects of long‐term cinnamon bark oil (CBO) ingestion on testicular antioxidant values, apoptotic germ cell and sperm quality of adult rats. Twelve male healthy Wistar rats were divided into two groups, each group containing six rats. While olive oil was given to control group, 100 mg kg?1 CBO was administered to the other group by gavage daily for 10 weeks. Body and reproductive organ weights, sperm characteristics, testicular lipid peroxidation and antioxidant enzyme activities, and testicular apoptosis via terminal deoxynucleotidyl transferase–mediated dUTP nick end labelling (TUNEL) method were examined. A significant decrease in malondialdehyde level and marked increases in reduced glutathione level, glutathione peroxidase and catalase activities were observed in rats treated with CBO compared with the control group. CBO consumption provided a significant increase in weights of testes and epididymides, epididymal sperm concentration, sperm motility and diameter of seminiferous tubules when compared with the control group. However, CBO consumption tended to decrease the abnormal sperm rate and apoptotic germ cell count, but it did not reach statistical significance. It is concluded that CBO has improvement effect on testicular oxidant–antioxidant balance and sperm quality, and its consumption may be useful for asthenozoospermic men.  相似文献   

7.
This study investigates the ameliorative potential of Launea taraxacifolia (LT) aqueous leaf extract on cisplatin‐induced testicular dysfunction in Wistar rats. Thirty rats were randomly divided into six groups (A–F) of 5 rats each: Group A which served as control received water; Group B was intraperitoneally (ip) injected 10 mg kg?1 body wt cisplatin on day 21; Groups C and D were given 100 and 400 mg of LT via oral administration, respectively, for 21 days while Groups E and F received similar treatment as Groups C and D, respectively, and then exposed to ip administration of 10 mg kg?1 body weight cisplatin on the 21st day. Exclusively, Cisplatin‐exposed Group B rats showed reduced sperm characteristics and increased sperm morphological abnormalities; distorted histological architecture of seminiferous tubules; significantly increased lipid peroxidation (LPO) and decreased activities of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH)levels in the testes. These parameters in LT alone treated Groups C and D were not markedly different compared with the control group. The rats with the combined treatment in Groups E and F showed significantly improved sperm parameters, testicular histo‐architecture and antioxidant enzymatic activities. Conclusively, aqueous extract of L. taraxacifolia has protective potential against cisplatin damage.  相似文献   

8.
This study evaluated the protective effects of 6‐gingerol‐rich fraction (6‐GRF) from Zingiber officinale on carbendazim (CBZ)‐induced reproductive toxicity in rats. Adult male rats were treated with either CBZ (50 mg/kg) alone or in combination with 6‐GRF (50, 100 and 200 mg/kg) for 14 consecutive days. Gas chromatography–mass spectrometry (GCMS) analysis revealed that 6‐GRF consists of ten bioactive chemical components with 6‐gingerol being the most abundant (30.76%). Administration of 6‐GRF significantly (< .05) prevented CBZ‐mediated increase in absolute and relative testes weights as well as restored the sperm quantity and quality in the treated rats to near control. In testes and epididymis, 6‐GRF significantly abolished CBZ‐mediated increase in oxidative damage as well as augmented antioxidant enzymes activities and glutathione level in the treated rats. Moreover, CBZ administration alone significantly decreased plasma levels of testosterone, thyrotropin, triiodothyronine and tetraiodothyronine, whereas follicle‐stimulating hormone was significantly elevated without affecting luteinising hormone and prolactin levels when compared with the control. Conversely, 6‐GRF ameliorated the disruption in the hormonal levels and restored their levels to near normalcy in CBZ‐treated rats. Collectively, 6‐GRF inhibited the adverse effects of CBZ on the antioxidant defence systems, hormonal balance and histology of the testes and epididymis in rats.  相似文献   

9.
The protective role of gallic acid (GA) on reproductive toxicity induced by cyclophosphamide (CPA), an antineoplastic drug, was investigated in male Wistar rats. Sixty rats were grouped into 10 rats per group. Group 1 (control) received distilled water. Rats in groups 2 and 3 received GA alone at 60 and 120 mg kg?1 for 14 consecutive days, respectively. Group 4 received a single intraperitoneal dose of CPA at 200 mg kg?1 on day 1. Groups 5 and 6 received a single dose of CPA (200 mg kg?1) intraperitoneally on day 1 followed by treatment with GA at 60 and 120 mg kg?1 for 14 consecutive days, respectively. In testes and epididymis of the treated rats, CPA administration resulted in significant elevation (P < 0.05) in malondialdehyde (MDA), nitrite and hydrogen peroxide levels. There was a significant decrease in the activities of superoxide dismutase and glutathione‐S‐transferase. Furthermore, there were significant reductions in plasma luteinising hormone (LH), follicle stimulation hormone (FSH) and testosterone levels, which were accompanied by significant decrease in sperm motility and viability in CPA‐treated rats. Histological examination revealed marked testicular and epididymal atrophy in CPA alone treated rats and these aberrations were reversed by GA. In conclusion, GA has capacity to protect against reproductive toxicity induced by cyclophosphamide.  相似文献   

10.
Previous studies showed that exposure to stress or nicotine induced reproductive impairment in male rats. Here, we assessed the effect of an antioxidant (vitamin E) on nicotine‐, stress‐ and nicotine + stress‐induced reproductive impairment in male rats. Forty‐eight male albino Wistar rats were divided into eight groups as follows; control, stress (generator noise 90–120 dB, 8 hr/day), nicotine (1.5 mg kg?1 day?1), nicotine + stress, vitamin E (100 mg kg?1 day?1), stress + vitamin E, nicotine + vitamin E and stress + nicotine + vitamin E. Sperm count, viability, motility and rapid progressive forward movement decreased significantly (p < 0.05), while percentage of nonmotile spermatozoa increased significantly (p < 0.05) in stress, nicotine and nicotine + stress groups, compared with control. Serum testosterone and follicle‐stimulating hormone decreased significantly (p < 0.05) in stress, nicotine and nicotine + stress groups, compared with control. Serum luteinising hormone decreased (p < 0.05) significantly in stress and nicotine + stress groups, compared with the control. Histology of the testes showed loss of germ cells in numerous seminiferous tubules, and epididymal histology showed decreased sperm density in stress, nicotine and nicotine + stress groups compared with the control. These negative changes were more severe in the nicotine + stress group. Vitamin E ameliorated the negative changes in the above parameters. This may be attributable to its antioxidant property.  相似文献   

11.
Polychlorinated biphenyls (PCBs) are a group of environmental contaminants widely reported to cause gonadal toxicity in both humans and animals. This study investigated the amelioratory role of quercetin in PCBs‐induced DNA damage in male Wistar rats. Polychlorinated biphenyls were administered intraperitoneally at a dose of 2 mg kg?1 alone or in combination with quercetin (orally) at 50 mg kg?1 for 25 days. Quercetin modulation of PCBs‐induced gonadal toxicity was evaluated using selected oxidative stress indices, comet assay, measurement of DNA concentration and histology of the testes. Administration of PCBs alone caused a significant (P < 0.05) depletion in the total thiol level in testes of treated rats. Conversely, the levels of reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) production were markedly elevated in testes of PCBs‐treated rats compared with control. Further, PCBs exposure produced statistically significant increases in DNA tail migration, degraded double‐stranded DNA (dsDNA) concentration and histological alterations of testes of the treated rats compared to control. Quercetin cotreatment significantly improved the testicular antioxidant status, decreased DNA fragmentation and restored the testicular histology, thus demonstrating the protective effect of quercetin in PCBs‐treated rats.  相似文献   

12.
An aqueous extract of Eurycoma longifolia (Tongkat Ali; TA) roots is traditionally used to enhance male sexuality. Because previous studies are limited to only few sperm parameters or testosterone concentration, this study investigated the in vivo effects of TA on body and organ weight as well as functional sperm parameters in terms of safety and efficacy in the management of male infertility. Forty‐two male rats were divided into a control, low‐dose (200 mg kg?1 BW) and high‐dose (800 mg kg?1 BW) group (n = 14). Rats were force‐fed for 14 days and then sacrificed. Total body and organ weights of the prostate, testes, epididymides, gastrocnemius muscle and the omentum were recorded. Moreover, testosterone concentration, sperm concentration, motility, velocity, vitality, acrosome reaction and mitochondrial membrane potential (MMP) were assessed. Whilst TA decreased BW by 5.7% (P = 0.0276) and omentum fat by 31.9% (P = 0.0496), no changes in organ weights were found for the prostate, testes and epididymides. Testosterone concentration increased by 30.2% (P = 0.0544). Muscle weight also increased, yet not significantly. Whilst sperm concentration, total and progressive motility and vitality increased significantly, MMP improved markedly (P = 0.0765) by 25.1%. Because no detrimental effect could be observed, TA appears safe for possible treatment of male infertility and ageing male problems.  相似文献   

13.
This study investigated the protective effects of melatonin (MT) against gentamicin (GM)‐induced testicular toxicity and oxidative damage in rats. GM (100 mg kg?1) was injected intraperitoneally (i.p.) to rats for 6 days. MT (15 mg kg?1) was administered i.p. to rats for 6 days at 1 hr after the GM treatment. GM caused a decrease in prostate and seminal vesicle weights, sperm count and sperm motility. Histopathological examination showed various morphological alterations in the testis, characterised by degeneration of spermatogonia/spermatocytes, decrease in the number of early spermatogenic cells and vacuolisation. In addition, an increased malondialdehyde concentration and decreased glutathione content and glutathione reductase, catalase and glutathione‐S‐transferase activities were found in the testis. In contrast, MT treatment significantly attenuated the testicular toxicity of GM, including decreased reproductive organ weights, sperm count, and sperm motility and increased histopathological alterations. MT also had an antioxidant benefit by decreasing the lipid peroxidative product malondialdehyde and increasing the level of the antioxidant glutathione and the activities of antioxidant enzymes in the testis. These results indicate that MT prevents testicular toxicity induced by GM in rats, presumably due to its potent antioxidant activity, and its ability to inhibit lipid peroxidation, and restore antioxidant enzyme activity.  相似文献   

14.
The study investigated the reproductive function and the antioxidant defence system of rats co‐exposed to atrazine [ATZ, 120 mg kg?1 body weight (b. wt)] and quercetin (QT, 20 mg kg?1 b. wt.). ATZ had no significant effects on feed intake, body weights and reproductive organs weight except prostate weight. Sperm abnormalities were increased, whereas sperm production, sperm motility and epididymal and testicular sperm numbers were decreased with ATZ treatment. Antioxidant enzymes including superoxide dismutase, glutathione‐S‐transferase and glutathione peroxidase were significantly altered in the epididymis and testis resulting to lipid peroxidation. A potentiating response on glutathione‐S‐transferase and aspartate aminotransferase activities in the testis and on lactate dehydrogenase activity and glutathione level in the epididymis was observed in the QT + ATZ animals. Quercetin alone decreased seminal vesicle and prostate weights, increased superoxide dismutase activity in the testis and ascorbate level in the epididymis. Mild pathological changes were observed in the ATZ group, whereas considerable necrosis of seminiferous tubular cells with hypoplasia of the epithelia was observed in the QT + ATZ animals. The epididymis of these animals had multilayered and sometimes a single lining epididymal epithelium with few spermatozoa. We conclude that quercetin at the investigated dose increases the susceptibility of rat reproductive tissues to atrazine‐induced oxidative damage.  相似文献   

15.
In this study, we investigated the protective ability of the addition of two antioxidant herb extracts, mate tea and lemon balm, on boar epididymal frozen–thawed spermatozoa quality. Testes from mature boars were collected at local slaughterhouse, and sperm samples from epididymis were recovered by flushing. Spermatozoa were cryopreserved in lactose–egg yolk buffer supplemented with various concentrations of lemon balm and mate tea (0, 2.5, 5 and 10 g l?1) using the straw‐freezing procedure. Motion parameters, acrosome and plasma membrane integrity, lipoperoxidation levels and DNA oxidative damage (8‐hydroxy‐2′‐deoxyguanosine base lesion) were evaluated. There were no differences among experimental groups with regard to motility characteristics, viability, acrosome and plasma membrane integrity; however, the highest concentration of lemon balm produced significant (P < 0.05) improvement in curvilinear trajectory, straightness and amplitude of lateral head displacement after thawing. The supplementation of freezing extender with mate tea and lemon balm reduced sperm lipid membrane peroxidation, and only mate tea protected DNA against oxidative damage during cryopreservation at 120 min post‐thawing (P < 0.05). Mate tea experimental extender at concentration of 10 g l?1 showed the lowest percentage of sperm oxidised DNA and malondialdehyde generation; thus, mate tea is a potential candidate such as antioxidant compound on boar sperm cryopreservation medium.  相似文献   

16.
We investigated the effects of folic acid and zinc sulphate supplementation on the improvement of sperm function in subfertile oligoasthenoteratozoospermic (OAT) men. Eighty‐three OAT men participated in a 16‐week intervention randomised, double‐blind clinical trial with daily treatment of folic acid (5 mg day?1) and zinc sulphate (220 mg day?1), or placebo. Before and after treatment, semen and blood samples were obtained for determining sperm concentration, motility, and morphology, sperm viability, sperm mitochondrial function, sperm chromatin status using toluidine blue, aniline blue, acridine orange and chromomycin A3 staining; and semen and blood folate, zinc, B12, total antioxidant capacity ( TAC) and malondialdehyde (MDA) concentrations. Sperm concentration (×106 ml?1) increased in subfertile men receiving the combined treatment of folic acid and zinc sulphate and also in the group receiving only folic acid treatment; however, it was not statistically significant (P = 0.056 and P = 0.05, respectively). Sperm chromatin integrity (%) increased significantly in subfertile men receiving only zinc sulphate treatment (P = 0.048). However, this improvement in sperm quality was not significant after adjusting placebo effect. This study showed that zinc sulphate and folic acid supplementation did not ameliorate sperm quality in infertile men with severely compromised sperm parameters, OAT. Male infertility is a multifactorial disorder, and also nutritional factors play an important role in results of administration of supplementation on sperm parameters. However, these results should be confirmed by multiple studies in larger populations of OAT men.  相似文献   

17.
Fenitrothion (FNT) is a widely used organophosphorus pesticide in agriculture. Quercetin (QR), a plant‐derived flavonoid, has a free radical scavenging property. This study investigated the protective effect of QR on FNT‐induced testicular toxicity in rats. Twenty‐four male rats were divided into four groups. Group I (control) received normal saline. Group II was administered QR at the dose of 50 mg kg?1 b.wt. Group III was orally administered FNT (20 mg kg?1 b.wt). Group IV was gavaged FNT and QR together at the same doses. All administrations were performed daily by gavage and maintained for 70 days. Sperm parameters and histopathological changes in testes were investigated. Serum testosterone and luteinising hormone were estimated using radioimmunoassay kits. In testes, expressions of steroidogenic genes (3β‐hydroxysteroid dehydrogenase type 6, 17 β‐hydroxysteroid dehydrogenase type 3 and steroidogenic factor‐1) and oxidative stress genes (catalase and superoxide dismutase) were determined using real‐time PCR. FNT administration caused significant decreases in sperm count, motility and hormonal levels, a significant increase in abnormal sperm morphology and a significant down‐regulation of steroidogenic and antioxidant genes in the testis. However, QR administration ameliorated FNT‐induced toxic effects. Our results concluded that QR effectively mitigated testicular damage induced by FNT in rats.  相似文献   

18.
Manganese inhibits oxidative stress damage. The aim of this study was to investigate the protective role of manganese on testis structure and sperm parameters in adult mice exposed to formaldehyde (FA). Twenty adult male NMRI mice were selected and randomly divided into four groups: (i) control; (ii) sham; (iii) ‘FA’‐exposed group; and (iv) ‘FA and manganese chloride’‐exposed group. The FA‐exposed groups received 10 mg kg?1 FA daily for 14 days, and manganese chloride was just injected intraperitoneally 5 mg kg?1 on 2nd weeks. Mice were sacrificed, and spermatozoa were collected from the cauda of the right epididymis and analysed for count, motility, morphology and viability. The other testicular tissues were weighed and prepared for histological examination upon removal. Seminiferous tubules, lumen diameters and epithelium thickness were also measured. The findings revealed that FA significantly reduced the testicular weight, sperm count, motility, viability and normal morphology compared with control group (P ≤ 0.05). In addition, seminiferous tubules atrophied and seminiferous epithelial cells disintegrated in the FA group in comparison with the control group (P ≤ 0.05). However, manganese improved the testicular structure and sperm parameters in FA‐treated mice testes (P ≤ 0.05). According to the results, manganese may improve and protect mice epididymal sperm parameters and testis structure treated with FA respectively.  相似文献   

19.
In this study, we aimed to investigate the effects of pentoxifylline (PTX) on male reproductive parameters in diabetic mice. Male adult mice (n = 24) were divided into control and three experimental groups (n = 6) including Diabetic, Diabetic + PTX and PTX groups. Diabetes was induced by single injection of streptozotocin (60 mg kg?1). PTX was administered intraperitoneally at the dose of 12 mg kg?1 for 14 days 1 week after diabetes induction. Serum levels of testosterone and blood glucose were determined and collected spermatozoa from cauda epididymidis analysed. Based on histological slides prepared from testis, the diameter of seminiferous tubules was determined using Motic camera and software and also apoptosis using TUNEL assay. Data were analysed using one‐way anova method, and P < 0.05 was considered statistically significant. The mean of seminiferous tubules diameter, final body weight, testis weight, sperm parameters and testosterone hormone level in PTX‐treated diabetic group indicated a significant increase compared to diabetic one, whereas apoptosis index and blood glucose were decreased in this comparison (P < 0.05). These results suggest that intraperitoneal administration of PTX is a potentially beneficial agent to reduce testicular damage and improves sperm parameters in diabetic mice by decreasing the ratio of apoptosis.  相似文献   

20.
The aim of this study was to compare the effectiveness of antioxidants including cysteamine (2.5, 7.5 mm ), hyaluronan (0.25, 1 mg ml?1) and fetuin (5, 10 mg ml?1) in the freezing of Brown Swiss bull semen. The best percentages of CASA motilities were achieved with 10 mg ml?1 of fetuin and 2.5 mm of cysteamine. For sperm morphology, 10 mg ml?1 of fetuin and 2.5 mm of cysteamine had better protective effects (P < 0.001). The results of hypo‐osmotic swelling test showed that the percentage values of membrane integrity in all the groups, excluding that supplemented with 5 mg ml?1 of fetuin, were higher than those of the control group (P < 0.001). Results obtained for the DNA damage of sperm cells demonstrated that 0.25 mg ml?1 of hyaluronan, and 2.5 and 7.5 mm of cysteamine led to lower rates of spermatozoa with damaged DNA, compared with the control group (P < 0.001). The maintenance of superoxide dismutase and glutathione peroxidase antioxidant activities following freeze‐thawing with 2.5 and 7.5 mm of cysteamine and 10 mg ml?1 of fetuin was demonstrated to be at a higher level in comparison with the control group (P < 0.001). Malondialdehyde formation was found to be lower in the groups supplemented with 0.25 mg ml?1 of hyaluronan and 7.5 mm of cysteamine after the freeze‐thawing process (P < 0.001).  相似文献   

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