Correction: Archibong, A.E., et al. Effects of Benzo(a)pyrene on Intra-testicular Function in F-344 Rats

We found some errors in Figure 4 in our paper published in the International journal of Environmental Research and Public Health [1].[...

Comparative Metabolism of Benzo(a)pyrene by Ovarian Microsomes of Various Species

Knowledge of the ability of the female reproductive system to metabolize polycyclic aromatic hydrocarbons (PAHs) is critical to the diagnosis and management of female infertility and for risk assessment purposes. The PAHs are a family of widespread pollutants that are released into the environment from automobile exhausts, cigarette smoke, burning of refuse, industrial emissions, and hazardous waste sites. In exposed animals, PAHs become activated to reactive metabolites that interfere with target organ function and as a consequence cause toxicity. The extent of susceptibility to PAH exposure may depend on the ability of animals to metabolize these chemicals. The present study has been undertaken to assess whether any differences exist among mammals in the metabolism of benzo(a)pyrene (BaP), a prototypical PAH compound

Comparative Metabolism of Benzo(a)pyrene by Ovarian Microsomes of Various Species

Knowledge of the ability of the female reproductive system to metabolize polycyclic aromatic hydrocarbons (PAHs) is critical to the diagnosis and management of female infertility and for risk assessment purposes. The PAHs are a family of widespread pollutants that are released into the environment from automobile exhausts, cigarette smoke, burning of refuse, industrial emissions, and hazardous waste sites. In exposed animals, PAHs become activated to reactive metabolites that interfere with target organ function and as a consequence cause toxicity. The extent of susceptibility to PAH exposure may depend on the ability of animals to metabolize these chemicals. The present study has been undertaken to assess whether any differences exist among mammals in the metabolism of benzo(a)pyrene (BaP), a prototypical PAH compound

Perturbation of the Developmental Potential of Preimplantation Mouse Embryos by Hydroxyurea

Women are advised not to attempt pregnancy while on hydroxyurea (HU) due to the teratogenic effects of this agent, based on results obtained from animal studies. Several case reports suggest that HU may have minimal or no teratogenic effects on the developing human fetus. Fourteen cases of HU therapy in pregnant patients diagnosed with acute or chronic myelogenous leukemia, primary thrombocythemia, or sickle cell disease (SCD) have been reported. Three pregnancies were terminated by elective abortion; 1 woman developed eclampsia and delivered a phenotypically normal stillborn infant. All other patients delivered live, healthy infants without congenital anomalies. We contend that case studies such as these have too few patients and cannot effectively address the adverse effect of HU on preimplantation embryo or fetuses. The objective of this study was to assess the risks associated with a clinically relevant dose of HU used for the treatment of SCD, on ovulation rate and embryo development, using adult C57BL/6J female mice as a model. In Experiment 1, adult female mice were randomly assigned to a treatment or a control group (N = 20/group). Treatment consisted of oral HU (30 mg/kg) for 28 days; while control mice received saline (HU vehicle). Five days to the cessation of HU dosing, all mice were subjected to folliculogenesis induction with pregnant mare serum gonadotropin (PMSG). Five mice/group were anesthetized at 48 hours post PMSG to facilitate blood collection via cardiac puncture for estradiol-17β (E2) measurement by RIA. Ovulation was induced in the remaining mice at 48 hours post PMSG with human chorionic gonadotropin (hCG) and immediately caged with adult males for mating. Five plugged female mice/group were sacrificed for the determination of ovulation rate. The remaining mated mice were sacrificed about 26 hours post hCG, ovaries excised and weighed and embryos harvested and cultured in Whitten’s medium (WM) supplemented with CZBt. In Experiments 2 and 3, (N = 10/Experiment) folliculogenesis and ovulation were induced in untreated mice followed by mating. Recovered embryos were either exposed continuously (Experiment 2) or intermittently (Experiment 3) to bioavailable HU (18 μg HU/mL of WM + CZBt) or WM + CZBt only (control). Treated mice sustained decreased ovarian wt, ovulation rate and circulating E2 compared with controls (P < 0.05). Fewer embryos retrieved from HU-treated mice developed to blastocyst stage (32%) compared with those from controls (60%; P < 0.05). Furthermore, continuous or intermittent in vitro exposures of embryos to HU also resulted in reduced development to blastocyst stage (continuous HU, 9 vs. control, 63%; P < 0.05; intermittent HU, 20 vs. control, 62%; P < 0.05) with embryos exposed continuously to HU in vitro fairing worse. Even though HU is well tolerated, our data suggest that it compromises folliculogenesis and the ability of generated embryos to develop. Therefore, designed studies with larger numbers of patients receiving HU during pregnancy, with longer follow-up of exposed children and more careful assessment of embryo/fetotoxic effects, are required before this agent can be promoted as safe in pregnancy

Bone Marrow Transplantation Restores Follicular Maturation and Steroid Hormones Production in a Mouse Model for Primary Ovarian Failure

Recent studies suggest that bone marrow stem cells (BMSCs) are promising grafts to treat a variety of diseases, including reproductive dysfunction. Primary ovarian failure is characterized by amenorrhea and infertility in a normal karyotype female, with an elevated serum level of follicle-stimulating hormone (FSH) and a decrease level of estrogen caused by a mutation in FSH receptor (FSHR) gene. Currently, there is no effective treatment for this condition. The phenotype of FSHR (−/−) mouse, FORKO (follitropin receptor knockout), is a suitable model to study ovarian failure in humans. Female FORKO mice have elevated FSH, decreased estrogen levels, are sterile because of the absence of folliculogenesis, and display thin uteri and small nonfunctional ovaries. In this study, we determined the effects of BMSC transplantation on reproductive physiology in this animal model. Twenty four hours post BMSC transplantation, treated animals showed detectable estroidogeneic changes in daily vaginal smear. Significant increase in total body weight and reproductive organs was observed in treated animals. Hemotoxylin and eosin (H&E) evaluation of the ovaries demonstrated significant increase in both the maturation and the total number of the follicles in treated animals. The FSH dropped to 40–50% and estrogen increased 4–5.5 times in the serum of treated animals compared to controls. The FSHR mRNA was detected in the ovaries of treated animals. Our results show that intravenously injected BMSCs were able to reach the ovaries of FORKO mice, differentiate and express FHSR gene, make FSHR responsive to FSH, resume estrogen hormone production, and restore folliculogenesis

The Poet as A Crusader for Social Justice: Stylistic Implications in Niyi Osundare's Random Blues

The role of the poet as a crusader for social justice has been well-acknowledged in literary circles and beyond. This stems from the nature of art as a humanistic endeavor genetically imbued with the spirit of standing with humanity and freeing it from the stranglehold of social malfeasance, reprehensible and tendencious inclinations. Poetry is, therefore, a unique artistic expression of solidarity with the people and an aspiration or vision towards a better human experience. Osundare's social involvement through literary practice has meant the engagement of issues with the intent of exposing the contradictions that impoverish society. The social involvement and foregrounding of the thematic issues has entailed the mobilization of linguistic resources as stylistic strategies for poignancy and effective communication. This paper interrogates the meeting point between Osundare's social concerns in his Random Blues and the linguistic strategies he employs to the service of poetic communication. To this end, the paper analyses New Historicism which underscores the invocation of socio-political times in the production and interpretation of literature; and insights from Systemic Functional Linguistics that stress the place of function and relevance in determining linguistic choice and meaning. The paper concludes that as a social critic, Osundare has used poetry to spearhead a rude awakening of the oppressed in the society against the contradictions and manipulations by the powerful few, calling the latter to action and championing the cause to bring about social transformation and liberation from the chokehold of tyranny and oppression

Do Progestin-Only Contraceptives Contribute to the Risk of Developing Depression as Implied by Beta-Arrestin 1 Levels in Leukocytes? A Pilot Study

We reported previously that reduction in beta-arrestin 1 (&beta;-AR 1) protein levels in peripheral blood mononuclear leukocytes (PBMC) significantly correlated with the severity of depressive symptoms in reproductive women. In this pilot study, we used &beta;-AR 1 protein levels in PBMC as a marker for developing depressive symptoms and the Hamilton Depression Rating Scale (HAM-D) scores to assess potential mood-related side effects of oral contraceptive use for routine birth control among women. We evaluated 29 women in this study. We enrolled the participants in three groups: Estrogen-progestin combination-oral contraceptives (COC, n = 10), progestin-only contraceptives (POC, n = 12), and non-hormonal or no contraceptives (NC, n = 7). We determined the &beta;-AR 1 protein levels in PBMCs by enzyme-linked immunosorbent assay (ELISA). We found that women in the POC group had significantly higher HAM-D scores compared to those in the COC (p &lt; 0.0004) and NC (p &lt; 0.004). The levels of &beta;-AR 1 protein were significantly attenuated in women in the POC group compared to women in the NC group (p = 0.03). Our findings suggest that the use of POC is a potential risk factor for developing depressive symptoms

Effects of Benzo(a)pyrene on Intra-testicular Function in F-344 Rats

The objective of this study was to evaluate the reproductive risk associated with exposure of adult male Fisher-344 (F-344) rats to inhaled benzo(a)pyrene (BaP), a ubiquitous environmental toxicant present in cigarette smoke, automobile exhaust fumes and industrial emissions. Rats were assigned randomly to a treatment or control group. Treatment consisted of exposure of rats via nose-only inhalation to 75μg BaP/m3, 4 hours daily for 60 days, while control animals were unexposed (UNC). Blood samples were collected immediately on day 60 of exposures (time 0) and subsequently at 24, 48, and 72 hours, to assess the effect of exposures to BaP on plasma testosterone and luteinizing hormone (LH) concentrations. Mean testis weight, total weight of tubules and total tubular length per paired testes were reduced 33% (P< 0.025), 27% (P < 0.01) and 39%, respectively in exposed rats (P < 0.01) compared with UNC rats. The number of homogenization -resistant spermatids was significantly reduced in BaP-exposed versus UNC rats. Plasma testosterone and intra-testicular testosterone (ITT) concentrations were significantly decreased by BaP compared with those of UNC rats. The decreases in circulating plasma testosterone were accompanied by concomitant increases in plasma LH concentrations in BaP-exposed versus control rats (P < 0.05). These data suggest that 60 days exposure to inhaled BaP contribute to reduced testicular endocrine and spermatogenic functions in exposed rats