scholarly journals Prenatal Exposure to the Endocrine Disrupting Chemical DEHP Impacts Reproduction-Related Gene Expression in the Pituitary

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A491-A491
Author(s):  
Xiyu Ge ◽  
Karen Weis ◽  
Lori Raetzman
Keyword(s):  
Gene Expression ◽  
Prenatal Exposure ◽  
Mrna Level ◽  
In Vitro Experiments ◽  
Related Gene ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
Dehp Exposure

Abstract Phthalates are chemicals used in various common products including plastics and medical devices, leading to widespread contact. Phthalate exposure during embryonic development can cause changes in puberty timing, reduced fertility and genital abnormalities. Previous studies on prenatal exposure to Di-(2-ethylhexyl) phthalate (DEHP) in mice indicated that it disrupts pituitary-gonadal feedback and alters reproductive performance in the offspring, however, the mechanism behind this is unknown. We hypothesize that prenatal exposure to DEHP during a critical period of embryonic development (e15.5 to e18.5) will cause sex-specific disruptions in reproduction-related functions in the pituitary in offspring due to interference with androgen and aryl hydrocarbon receptor (AhR) signaling. In order to discover the direct effects of DEHP on the reproduction-related functions in the pituitary, we performed both in vivo dosing and in vitro pituitary culture experiments. First, we dosed pregnant CD-1 mice with corn oil, the antiandrogen flutamide or DEHP from gestational day 15.5 to 18.5, then collected the pituitaries of the offspring on postnatal day 0. We found that prenatal DEHP exposure caused a significant increase in Fshb specifically in males, and flutamide caused significant increases in both Lhb and Fshb in males. Besides, DEHP exposure significantly increased AhR pathway related gene Cyp1b1 in both males and females. In the in vitro experiment, we took whole pituitaries from e16.5 embryos and cultured them in media containing DEHP, MEHP and/or AhR antagonist for 72hrs. We found that the DEHP metabolite MEHP was actually the chemical that exerted the effects directly at the level of the pituitary. Similar to in vivo experiments, Cyp1a1 and Cyp1b1 mRNA level were increased in pituitaries treated with MEHP in both sexes and the induction could be reduced by co-treatment with AhR antagonist. The mRNA level of Lhb, Fshb and Gnrhr were significantly decreased in both sexes by MEHP and co-treatment with AhR antagonist did not restore mRNA levels. The induction of Cyp1a1/Cyp1b1 gene in both in vivo and in vitro experiments indicates the possible activation of AhR by DEHP/MEHP. The in vitro experiment with AhR antagonist further proved that the induction of Cyp1a1/Cyp1b1 was indeed due to AhR activation directly at the level of the pituitary. The difference between in vivo and in vitro experiments in terms of gonadotropin gene expression indicates multiple mechanisms should be involved in the regulation of gonadotropin gene expression in vivo including androgen-related pathways and possibly AhR-related pathways. In summary, our data suggest that phthalates can directly affect the function of the pituitary in terms of regulation of reproductive- related genes. This indicates that pituitary impacts of phthalates could contribute to reproductive dysfunction observed in exposed mice and humans.

In Vitro Experimental Investigation of the Integrity of the Stem–Cement Interface

2013 ◽  
Vol 647 ◽  
pp. 53-56
Author(s):  
Hong Yu Zhang ◽  
Leigh Fleming ◽  
Liam Blunt
Keyword(s):  
Experimental Investigation ◽  
Fluid Flow ◽  
Hip Replacement ◽  
Hip Prosthesis ◽  
Vitro Experiment ◽  
Cement Interface ◽  
In Vitro Experiment ◽  
Mechanical Bonding

The rationale behind failure of cemented total hip replacement is still far from being well understood in a mechanical and molecular perspective. In the present study, the integrity of the stem–cement interface was investigated through an in vitro experiment monitoring fluid flow along this interface. The results indicated that a good mechanical bonding formed at the stem–cement interface before debonding of this interface was induced by physiological loadings during the in vivo service of the hip prosthesis.

Cadmium Chloride Induces Memory Deficits and Hippocampal Damage by Activating the JNK/p66Shc/NADPH Oxidase Axis

2020 ◽  
Vol 39 (5) ◽  
pp. 477-490
Author(s):  
Attalla Farag El-kott ◽  
Ali S. Alshehri ◽  
Heba S. Khalifa ◽  
Abd-El-karim M. Abd-Lateif ◽  
Mohammad Ali Alshehri ◽  
...  
Keyword(s):  
Nadph Oxidase ◽  
Cadmium Chloride ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Male Rats ◽  
Hippocampal Damage ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
In Vivo Experiment

This study investigated whether the mechanism underlying the neurotoxic effects of cadmium chloride (CdCl2) in rats involves p66Shc. This study comprised an initial in vivo experiment followed by an in vitro experiment. For the in vivo experiment, male rats were orally administered saline (vehicle) or CdCl2 (0.05 mg/kg) for 30 days. Thereafter, spatial and retention memory of rats were tested and their hippocampi were used for biochemical and molecular analyses. For the in vitro experiment, control or p66Shc-deficient hippocampal cells were treated with CdCl2 (25 µM) in the presence or absence of SP600125, a c-Jun N-terminal kinase (JNK) inhibitor. Cadmium chloride impaired the spatial learning and retention memory of rats; depleted levels of glutathione and manganese superoxide dismutase; increased reactive oxygen species (ROS), tumor necrosis factor α, and interleukin 6; and induced nuclear factor kappa B activation. Cadmium chloride also decreased the number of pyramidal cells in the CA1 region and induced severe damage to the mitochondria and endoplasmic reticulum of cells in the hippocampi of rats. Moreover, CdCl2 increased the total unphosphorylated p66Shc, phosphorylated (Ser36) p66Shc, phosphorylated JNK, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, cytochrome c, and cleaved caspase-3. A dose–response increase in cell death, ROS, DNA damage, p66Shc, and NADPH oxidase was also observed in cultured hippocampal cells treated with CdCl2. Of note, all of these biochemical changes were attenuated by silencing p66Shc or inhibiting JNK with SP600125. In conclusion, CdCl2 induces hippocampal ROS generation and apoptosis by promoting the JNK-mediated activation of p66Shc.

Effects of adaptation to lasalocid, monensin or a daily rotation of lasalocid and monensin on in vitro fermentation of a 90% concentrate diet

1995 ◽  
Vol 75 (1) ◽  
pp. 129-134 ◽  
Author(s):  
G. C. Duff ◽  
M. L. Galyean ◽  
M. E. Branine
Keyword(s):  
Key Words ◽  
In Vitro Experiments ◽  
In Vitro Fermentation ◽  
Ruminal Fluid ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
In Vitro Incubation

Effects of adaptation to L, M or a daily rotation of L and M (R) on in vitro fermentation were measured in a replicated in vitro experiment with a 4 × 4 factorial arrangement of treatments. Treatments were adaptation of ruminal fluid donor steers (0 or 200 mg steer−1 d−1 of L, M or R) and culture ionophore treatment (0 or 4 μg mL−1 of L, M or a 50:50 mixture of L and M). At 12 and 24 h, IVDMD was increased (P < 0.05) by adaptation to L compared with M, and decreased at 12 h (P < 0.05) by adaptation to R compared with the average of L and M adaptation. At 6 and 12 h, culture ionophore treatments increased (P < 0.10) IVDMD, compared with control. After 24 and 48 h of in vitro incubation, L adaptation increased (P < 0.01) acetate, decreased (P < 0.01) propionate, increased the acetate/propionate ratio (P < 0.01), and increased total VF A (P < 0.05), compared with M adaptation. Total VFA was increased (P < 0.10) for ionophore adaptation treatments compared with control at 48 h of incubation. Culture ionophore treatments decreased (P < 0.10) acetate and increased (P < 0.05) propionate at 24 and 48 h and decreased the acetate/propionate ratio (P < 0.10) at 24 h of incubation versus control cultures, with no measurable effects on total VFA. Adaptation treatments did not interact with culture treatments, suggesting that animals used as inoculum donors for in vitro experiments involving ionophores need not be adapted to an ionophore. Key words: In vitro, fermentation, ionophores, monensin, lasalocid

Surface Changes of Fluoride-Releasing Composites: a Comparison of in Vivo and in Vitro Results

1995 ◽  
Vol 9 (4) ◽  
pp. 348-354 ◽  
Author(s):  
G.E.H.M. Dijkman ◽  
J. De Vries ◽  
W.L. Jongebloed ◽  
J. Arends
Keyword(s):  
Mechanical Properties ◽  
Outer Surface ◽  
Tap Water ◽  
Surface Microhardness ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
Over Time ◽  
Surface Changes

Fluoride-releasing composites lose fluoride very slowly over time. An interesting question is the possible change in mechanical properties related to the F release. If this happens, it might be expected that the mechanical properties of the outer surface of a fluoridating composite are affected first. The purpose of this study was to investigate in vivo and in vitro the changes in surface microhardness and surface structure of three fluoride-releasing composites and a non-F-containing control after 28 days. In the in vitro experiment, the composites were stored in tap water at 37°C. The results show that all composites stored in water were significantly softened after 28 days. In vivo, however, a very different picture emerged: The surface microhardness of the fluoride-releasing composites did not change significantly. In vitro, the data indicate that the amount of softening of the fluoridating composites is related to the amount of fluoride released. No relation was found between the amount of F released in one month in vitro and the microhardness changes in vivo. SEM micrographs of fluoridating composites do not reflect the microhardness changes mentioned.

scholarly journals Alternative control of post-harvest diseases in Tainung 1 papaya

2018 ◽  
Vol 48 (1) ◽  
pp. 29-35 ◽  
Author(s):  
Andréa Mirne de Macêdo Dantas ◽  
Selma Rogéria de Carvalho Nascimento ◽  
Beatriz Letícia Silva da Cruz ◽  
Fernando Henrique Alves da Silva ◽  
Márcia Michelle de Queiroz Ambrósio ◽  
...  
Keyword(s):  
Essential Oil ◽  
Mycelial Growth ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
Post Harvest ◽  
Randomized Design ◽  
Clove Essential Oil

ABSTRACT Controlling post-harvest papaya diseases without using agrochemicals is a challenge for producers. This study aimed at evaluating the effect of clove essential oil, biological fungicide (Trichodermil®), resistance inducer (Cob Sistem®) and chemical fungicide (Imazacure®) on the in vitro control of phytopathogenic fungi isolates from papaya as well as on the post-harvest quality of Tainung 1 papaya. The in vitro experiment was conducted in a complete randomized design, with five fungal species x five treatments and five replications. The in vivo experiment was conducted in a complete randomized design, with five treatments x five storage times, five replications and three fruits per replication. The fruits were stored under refrigeration at 10 ± 2 ºC and 90 ± 5 % of relative humidity and evaluated at 0, 7, 14, 21 and 28 days of storage, plus two shelf life days at 25 ± 2 ºC, to simulate marketing conditions. The inhibition of mycelial growth was evaluated in the in vitro experiment, while the diseases occurrence and post-harvest quality of the fruits were evaluated in the in vivo experiment. The clove essential oil and Trichodermil® were as efficient as Imazacure® in inhibiting the mycelial growth of Alternaria sp., Colletotrichum gloeosporioides and Rhizopus sp. The treatments with clove essential oil, Trichodermil® and Imazacure® were similar in controlling the pathogens up to 21 days of storage. The treatments had no effect on the fruits soluble solid contents.

scholarly journals Study the effect of the mixture of alcoholic extract of Peganum harmala seeds & Pericarp of Punica granutum on viability of protoscolices of Echinococcus granulosus in vitro and in vivo

2013 ◽  
Vol 7 (2) ◽  
pp. 39-46
Author(s):  
Fawzia Ahmed AL-Shanawi ◽  
Noor Nihad Baker
Keyword(s):  
Echinococcus Granulosus ◽  
Infected Group ◽  
Alcoholic Extract ◽  
Peganum Harmala ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
Complete Inactivation

This study included the preparation of the mixture of alcoholic extracts of Peganum harmala seeds and Pericarp of Punica granutum at concentration (1+40), (1.5+45), (2+50) mgml. To study the influence of the mixture of alcoholic extracts of P. harmala and P. granutum on viability of the protoscolices of Echinococcus granulosus In vitro (In tubes), and In vivo (In albaino white mice injected intraperitoneal with protoscolices). In vitro experiment revealed complete inactivation of protoscolices (death) with concentration (2+ 50) mg/ ml after 30 minute. In vivo a significant reduction in weight of liver and spleen occurred in treated groups in comparison to control (untreated) infected group.

scholarly journals In vitro versus In vivo: Development-, Apoptosis-, and Implantation-Related Gene Expression in Mouse Blastocyst

2019 ◽  
Vol 17 (1) ◽  
pp. 90-97 ◽  
Author(s):  
Forough Mahdavinezhad ◽  
Parinaz Kazemi ◽  
Parisa Fathalizadeh ◽  
Fatemeh Sarmadi ◽  
Ehsan Hashemi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Related Gene ◽  
Mouse Blastocyst

An In-Vitro Experiment to Study Sustained Torque on the Spine

2009 ◽  
Author(s):  
Robert Rizza ◽  
Xue-Cheng Liu ◽  
Mohammad Mahinfalah ◽  
Yu Wang ◽  
John Thometz ◽  
...  
Keyword(s):  
Shear Force ◽  
Bone Growth ◽  
Axial Loading ◽  
Spinal Curvature ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
Immature Spine ◽  
Tension Loading

In adolescent scoliosis patients, as the vicious cycle hypothesis proposed by Dr. Stokes suggests [1], a lateral spinal curvature produces asymmetrical loading of the skeletally immature spine, which in turn causes asymmetrical growth and therefore progressive wedging deformity. Numerous studies have been done to evaluate the effect of sustained compression or tension loading on the spinal bone growth [2,3]. However, in scoliosis patients, there is not only the asymmetrical axial loading which will worsen the curve progression, but also constant shear force in the transverse plane that may affect the bone growth. So far, no in vivo experiment has been done to study the effect of shear force on the spine. The goal of this study is to design an in vitro experiment that will provide incessant torques in the calves’ tails, and determine the relationship between the magnitude of the torque and change of stress between tail segments.

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