Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 53
Filter
1.
Environ Toxicol Chem ; 42(8): 1730-1742, 2023 08.
Article in English | MEDLINE | ID: mdl-37132612

ABSTRACT

The pituitary gland is a central regulator of reproduction, producing two gonadotropins, follicle-stimulating hormone (Fsh) and luteinizing hormone (Lh), which regulate gonadal development, sex steroid synthesis, and gamete maturation. The present study sought to optimize an in vitro test system using pituitary cells isolated from previtellogenic female coho salmon and rainbow trout, focusing on fshb and lhb subunit gene expression. Initially, we optimized culture conditions for duration and benefits of culturing with and without addition of endogenous sex steroids (17ß-estradiol [E2] or 11-ketotestosterone) or gonadotropin-releasing hormone (GnRH). The results suggest that culturing with and without E2 was valuable because it could mimic the (+) feedback effects on Lh that are observed from in vivo studies. After optimizing assay conditions, a suite of 12 contaminants and other hormones was evaluated for their effects on fshb and lhb gene expression. Each chemical was tested at four to five different concentrations up to solubility limitations in cell culture media. The results indicate that more chemicals alter lhb synthesis than fshb. The more potent chemicals were estrogens (E2 and 17α-ethynylestradiol) and the aromatizable androgen testosterone, which induced lhb. The estrogen antagonists 4-OH-tamoxifen and prochloraz decreased the E2-stimulated expression of lhb. Among several selective serotonin reuptake inhibitors tested, the sertraline metabolite norsertraline was notable for both increasing fshb synthesis and decreasing the E2 stimulation of lhb. These results indicate that diverse types of chemicals can alter gonadotropin production in fish. Furthermore, we have shown that pituitary cell culture is useful for screening chemicals with potential endocrine-disrupting activity and can support the development of quantitative adverse outcome pathways in fish. Environ Toxicol Chem 2023;42:1730-1742. © 2023 SETAC.


Subject(s)
Salmonidae , Animals , Female , Salmonidae/metabolism , Pituitary Gland/metabolism , Gonadotropin-Releasing Hormone/metabolism , Gonadotropin-Releasing Hormone/pharmacology , Estradiol/metabolism , Reproduction , Steroids/metabolism
2.
Aquat Toxicol ; 217: 105346, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31704580

ABSTRACT

Endogenous estrogens play major roles in many aspects of female reproductive development in fish. In order to develop a relatively high-throughput assay to determine the potential impact on reproductive development, vitellogenic rainbow trout ovarian follicles were exposed to a suite of contaminants in vitro and then assessed for the ability to produce estradiol-17ß (E2) after a 500 ng/ml salmon gonadotropin (sGTH) challenge. There was a positive correlation between ovarian follicle size and E2 production, but an inverse correlation between size and responsiveness to sGTH. Significant impacts on E2 levels were observed following treatment with different endocrine disrupting chemicals, such as 17α-ethinylestradiol (EE2), prochloraz, or trenbolone. EE2 was remarkably potent and significantly reduced ovarian follicle responsiveness to sGTH at concentrations as low as 0.1 nM. Of the other contaminants tested, only tamoxifen impacted E2 levels, and only at concentrations near the limits of solubility. Flutamide, fluoxetine, 4-hydroxy tamoxifen, hydroxyflutamide, and norfluoxetine had little or no impact. Quantitative PCR analyses of steroidogenesis-related genes were carried out on EE2 treated ovarian follicles, but significant transcriptional responses to EE2 were not observed. Overall, this study suggests that xenoestrogens and anti-estrogens are more likely to interfere with ovarian E2 synthesis than other classes of EDCs. This also provides a template for further testing of the effects of EDCs on ovarian function.


Subject(s)
Endocrine Disruptors/toxicity , Estradiol/biosynthesis , Gonadotropins/pharmacology , Oncorhynchus mykiss/physiology , Ovarian Follicle/drug effects , Vitellogenesis/drug effects , Water Pollutants, Chemical/toxicity , Animals , Female , In Vitro Techniques , Ovarian Follicle/metabolism
3.
Aquat Toxicol ; 214: 105231, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31295703

ABSTRACT

Untreated urban runoff poses significant water quality threats to aquatic organisms. In northwestern North America, ongoing development in coastal watersheds is increasing the transport of toxic chemical contaminants to river and stream networks that provide spawning and rearing habitats for several species of Pacific salmon. Adult coho (Oncorhynchus kisutch) are particularly vulnerable to a stormwater-driven mortality syndrome. The phenomenon may prematurely kill more than half of the coho that return each fall to spawn in catchments with a high degree of imperviousness. Here we evaluate the coho mortality syndrome at the juvenile life stage. Freshwater-stage juveniles were exposed to stormwater collected from a high traffic volume urban arterial roadway. Symptoms characteristic of the mortality syndrome were evaluated using digital image analysis, and discrete stages of abnormal behavior were characterized as the syndrome progressed. At a subset of these stages, blood was analyzed for ion homeostasis, hematocrit, pH, glucose, and lactate. Several of these blood chemistry parameters were significantly dysregulated in symptomatic juvenile coho. Affected fish did not recover when transferred to clean water, suggesting a single runoff event to stream habitats could be lethal if resident coho become overtly symptomatic. Among coho life stages, our findings indicate the urban runoff mortality syndrome is not unique to adult spawners. Therefore, the consequences for wild coho populations in developing watersheds are likely to be greater than previously anticipated.


Subject(s)
Oncorhynchus kisutch/physiology , Water , Animals , Behavior, Animal , Fresh Water , Oncorhynchus kisutch/blood , Principal Component Analysis , Water Pollutants, Chemical/toxicity , Water Quality
4.
Mol Cell Endocrinol ; 460: 104-122, 2018 01 15.
Article in English | MEDLINE | ID: mdl-28711606

ABSTRACT

Although estrogens have been generally considered to play a critical role in ovarian differentiation in non-mammalian vertebrates, the specific functions of estrogens during ovarian differentiation remain unclear. We isolated two mutants with premature stops in the ovarian aromatase (cyp19a1) gene from an N-ethyl-N-nitrosourea-based gene-driven mutagenesis library of the medaka, Oryzias latipes. In XX mutants, gonads first differentiated into normal ovaries containing many ovarian follicles that failed to accumulate yolk. Subsequently, ovarian tissues underwent extensive degeneration, followed by the appearance of testicular tissues on the dorsal side of ovaries. In the newly formed testicular tissue, strong expression of gsdf was detected in sox9a2-positive somatic cells surrounding germline stem cells suggesting that gsdf plays an important role in testicular differentiation during estrogen-depleted female-to-male sex reversal. We conclude that endogenous estrogens synthesized after fertilization are not essential for early ovarian differentiation but are critical for the maintenance of adult ovaries.


Subject(s)
Loss of Function Mutation/genetics , Oryzias/genetics , Ovary/pathology , Sex Determination Processes , Sexual Maturation , Amino Acid Sequence , Animals , Aromatase/chemistry , Aromatase/genetics , Base Sequence , Cell Lineage , Down-Regulation/genetics , Estrogens/biosynthesis , Female , Gene Expression Profiling , Male , Ovarian Follicle/pathology , Sex Determination Processes/genetics , Testis/pathology , Up-Regulation/genetics , Vitellogenins/metabolism
5.
Biol Reprod ; 97(5): 731-745, 2017 Nov 01.
Article in English | MEDLINE | ID: mdl-29045593

ABSTRACT

Recent studies using several teleost models have revealed that androgens increase the size of previtellogenic (primary and/or early secondary) ovarian follicles. To explore our hypothesis that androgens drive the development of primary follicles into early secondary follicles, and to determine the mechanisms underlying these androgenic effects, we exposed juvenile coho salmon to near-physiological and relatively sustained levels of the nonaromatizable androgen 11-ketotestosterone (11-KT). This resulted in significant growth of primary ovarian follicles after 10 and 20 days, with follicles after 20 days displaying a morphological phenotype characteristic of early secondary follicles (presence of cortical alveoli). Utilizing the same experimental approach, we then analyzed how 11-KT rapidly altered the ovarian transcriptome after 1 and 3 days of treatment. RNA-Seq analysis revealed that 69 (day 1) and 1,022 (day 3) contiguous sequences (contigs) were differentially expressed relative to controls. The differentially expressed contigs mapped to genes including those encoding proteins involved in gonadotropin, steroid hormone, and growth factor signaling, and in cell and ovarian development, including genes with putative androgen-response elements. Biological functions and canonical pathways identified as potentially altered by 11-KT include those involved in ovarian development, tissue differentiation and remodeling, and lipid metabolism. We conclude that androgens play a major role in stimulating primary ovarian follicle development and the transition into secondary growth.


Subject(s)
Androgens/pharmacology , Oncorhynchus kisutch , Ovarian Follicle/drug effects , Testosterone/analogs & derivatives , Transcriptome/drug effects , Animals , Female , Testosterone/pharmacology
6.
Article in English | MEDLINE | ID: mdl-27387444

ABSTRACT

At the completion of vitellogenesis, the steroid biosynthetic pathway in teleost ovarian follicles switches from estradiol-17ß (E2) to maturational progestin production, associated with decreased follicle stimulating hormone (Fsh) and increased luteinizing hormone (Lh) signaling. This study compared effects of gonadotropins, human insulin-like growth factor-I (IGF1), and cAMP/protein kinase A signaling (forskolin) on E2 production and levels of mRNAs encoding steroidogenic proteins and gonadotropin receptors using midvitellogenic (MV) and late/postvitellogenic (L/PV) ovarian follicles of rainbow trout. Fsh, Lh and forskolin, but not IGF1, increased testosterone and E2 production in MV and L/PV follicles. Fsh increased steroidogenic acute regulatory protein (star; MV), 3ß-hydroxysteroid dehydrogenase/Δ(5-4) isomerase (hsd3b; MV) and P450 aromatase (cyp19a1a; MV) transcript levels. Lh increased star mRNA levels (MV, L/PV) but reduced cyp19a1a transcripts in L/PV follicles. At both follicle stages, IGF1 reduced levels of hsd3b transcripts. In MV follicles, IGF1 decreased P450 side-chain cleavage enzyme (cyp11a1) transcripts but increased cyp19a1a transcripts. In MV follicles only, forskolin increased star and hsd3b transcripts. Forskolin reduced MV follicle cyp11a1 transcripts and reduced cyp19a1a transcripts in follicles at both stages. Fsh and Lh reduced fshr transcripts in L/PV follicles. Lh also reduced lhcgr transcripts (L/PV). IGF1 had no effect on gonadotropin receptor transcripts. Forskolin reduced MV follicle fshr transcript levels and reduced lhcgr transcripts in L/PV follicles. These results reveal hormone- and stage-specific transcriptional regulation of steroidogenic protein and gonadotropin receptor genes and suggest that the steroidogenic shift at the completion of vitellogenesis involves loss of stimulatory effects of Fsh and Igfs on cyp19a1a expression and inhibition of cyp19a1a transcription by Lh.


Subject(s)
Fish Proteins/genetics , Gonadal Steroid Hormones/biosynthesis , Oncorhynchus mykiss/genetics , Oncorhynchus mykiss/physiology , Receptors, Gonadotropin/genetics , Animals , Aromatase/genetics , Cholesterol Side-Chain Cleavage Enzyme/genetics , Colforsin/pharmacology , Cyclic AMP/metabolism , Estradiol/biosynthesis , Female , Insulin-Like Growth Factor I/metabolism , Multienzyme Complexes/genetics , Ovarian Follicle/drug effects , Ovarian Follicle/physiology , Phosphoproteins/genetics , Progesterone Reductase/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Steroid Isomerases/genetics , Testosterone/biosynthesis , Vitellogenesis/genetics , Vitellogenesis/physiology
7.
Article in English | MEDLINE | ID: mdl-27320185

ABSTRACT

Molecular processes that either regulate ovarian atresia or are consequences of atresia are poorly understood in teleost fishes. We hypothesized that feed restriction that perturbs normal ovarian growth and induces follicular atresia would alter ovarian gene expression patterns. Previtellogenic, two-year old coho salmon (Oncorhynchus kisutch) were subjected to prolonged fasting to induce atresia or maintained on a normal feeding schedule that would promote continued ovarian development. To identify genes that were specifically up- or down-regulated during oocyte growth in healthy, growing fish compared to fasted fish, reciprocal suppression subtractive hybridization (SSH) cDNA libraries were generated using ovaries from fed and fasted animals. Differential expression of genes identified by SSH was confirmed with quantitative PCR. The SSH library representing genes elevated in ovaries of fed fish relative to those of fasted fish contained steroidogenesis-related genes (e.g., hydroxy-delta-5-steroid dehydrogenase), Tgf-beta superfamily members (e.g., anti-Mullerian hormone) and cytoskeletal intermediate filament proteins (e.g., type I keratin s8). Overall, these genes were associated with steroid production, cell proliferation and differentiation, and ovarian epithelialization. The library representing genes elevated in ovaries of fasted fish relative to fed fish contained genes associated with apoptosis (e.g., programmed cell death protein 4), cortical alveoli (e.g., alveolin), the zona pellucida (e.g., zona pellucida protein c), and microtubules (e.g., microtubule associated protein tau). Elevated expression of this suite of genes was likely associated with the initiation of atresia and/or a reduced rate of follicle development in response to fasting. This study revealed ovarian genes involved in normal early secondary oocyte growth and potential early markers of atresia.


Subject(s)
Follicular Atresia/genetics , Oncorhynchus kisutch/genetics , Animals , Fasting , Female , Fish Proteins/genetics , Follicular Atresia/physiology , Gene Expression , Gene Library , Oncorhynchus kisutch/growth & development , Oncorhynchus kisutch/physiology , Ovarian Follicle/cytology , Ovarian Follicle/growth & development , Ovarian Follicle/metabolism , Steroids/biosynthesis , Subtractive Hybridization Techniques , Transforming Growth Factor beta/genetics
8.
Ophthalmology ; 123(8): 1731-1736, 2016 08.
Article in English | MEDLINE | ID: mdl-27206840

ABSTRACT

PURPOSE: The objective of the study was to evaluate the accuracy of the Notal OCT Analyzer (NOA) versus that of a retina specialist (RS) in the automated detection of fluid on optical coherence tomography (OCT). DESIGN: A study of the performance of the NOA compared with the results from 3 RSs. PARTICIPANTS: A selection of 155 anonymized OCT scans (Zeiss Cirrus; Carl Zeiss Meditec, Dublin, CA) from an image repository at a single tertiary referral retina center (Belfast Health and Social Care Trust, Belfast, United Kingdom) after approval from the local data guardian of the clinical site. METHODS: One hundred fifty-five OCT cube scans were stripped of all clinical identifiers and exported. The NOA and 3 independent RSs analyzed all 128 B-scans of each cube scan for the presence of intraretinal fluid, subretinal fluid, and sub-retinal pigment epithelium fluid. The NOA also ranked individual B-scans of each volume scan for likelihood of CNV activity, which was subjected to a second grading session by the 3 RSs. MAIN OUTCOME MEASURES: The NOA's sensitivity and specificity versus the RS grading and the NOA's performance in ranking B-scans for activity. RESULTS: One hundred forty-two cube scans met the inclusion criteria for the primary analysis. On testing the RS grading versus the NOA, the accuracy was 91% (95% confidence interval [CI], ±7%), sensitivity was 92% (95% CI, ±6%), and specificity was 91% (95% CI, ±6%), meeting the primary outcome. The graders' accuracy when compared with the majority of the other graders (including a fourth grader) was 93%. On average, the 3 graders could identify fluid in 95% of scans by just reviewing a single cross-section with the highest NOA score and 99.5% of scans with fluid by viewing the top 3 cross-sections. CONCLUSIONS: Concordance between the NOA and the RS determination of lesion activity was extremely high. The level of discrepancy between the RS and the NOA results was similar to the NOA's mismatches. Our results show that automated delineation of the retinal contours combined with interpretation of disease activity is feasible and has the potential to become a powerful tool in terms of its clinical applications.


Subject(s)
Choroidal Neovascularization/diagnosis , Ophthalmology , Specialization , Subretinal Fluid , Tomography, Optical Coherence , Wet Macular Degeneration/diagnosis , False Positive Reactions , Female , Humans , Machine Learning , Male , Predictive Value of Tests , Prospective Studies , ROC Curve , Reproducibility of Results , Sensitivity and Specificity , United Kingdom
9.
Cent European J Urol ; 69(1): 98-104, 2016.
Article in English | MEDLINE | ID: mdl-27123335

ABSTRACT

Our "tips and tricks" focuses on all aspects of upper tract endourology and we hope these will be of use to all trainees and consultants who perform ureteroscopy. We report an "expert consensus view" from experienced endourological surgeons, on all aspects of advanced ureteroscopic techniques, with a particular focus on avoiding and getting out of trouble while performing ureteroscopy. In this paper we provide a summary of placing ureteric access sheath, flexible ureteroscopy, intra renal stone fragmentation and retrieval, maintaining visual clarity and biopsy of ureteric and pelvicalyceal tumours.

10.
Environ Pollut ; 213: 254-267, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26907702

ABSTRACT

This study was designed to assess the occurrence and concentrations of a broad range of contaminants of emerging concern (CECs) from three local estuaries within a large estuarine ecosystem. In addition to effluent from two wastewater treatment plants (WWTP), we sampled water and whole-body juvenile Chinook salmon (Oncorhynchus tshawytscha) and Pacific staghorn sculpin (Leptocottus armatus) in estuaries receiving effluent. We analyzed these matrices for 150 compounds, which included pharmaceuticals, personal care products (PPCPs), and several industrial compounds. Collectively, we detected 81 analytes in effluent, 25 analytes in estuary water, and 42 analytes in fish tissue. A number of compounds, including sertraline, triclosan, estrone, fluoxetine, metformin, and nonylphenol were detected in water and tissue at concentrations that may cause adverse effects in fish. Interestingly, 29 CEC analytes were detected in effluent and fish tissue, but not in estuarine waters, indicating a high potential for bioaccumulation for these compounds. Although concentrations of most detected analytes were present at relatively low concentrations, our analysis revealed that overall CEC inputs to each estuary amount to several kilograms of these compounds per day. This study is unique because we report on CEC concentrations in estuarine waters and whole-body fish, which are both uncommon in the literature. A noteworthy finding was the preferential bioaccumulation of CECs in free-ranging juvenile Chinook salmon relative to staghorn sculpin, a benthic species with relatively high site fidelity.


Subject(s)
Ecosystem , Estuaries , Wastewater/chemistry , Water Pollutants, Chemical/chemistry , Animals , Fishes
11.
Cent European J Urol ; 68(4): 439-46, 2015.
Article in English | MEDLINE | ID: mdl-26855797

ABSTRACT

Ureteroscopy is fast becoming the first line treatment option for the majority of urinary tract stones. Ureteroscopy training can be performed in a variety of ways including simulation, hands on ureteroscopy courses and supervised operative experience. We report an "expert consensus view" from experienced endourological surgeons, on all aspects of basic ureteroscopic techniques, with a particular focus on avoiding and getting out of trouble while performing ureteroscopy. In this paper we provide a summary of treatment planning, positioning, cannulation of ureteric orifice, guidewire placement, rigid ureteroscopy and stone fragmentation.

12.
Aquat Toxicol ; 142-143: 146-63, 2013 Oct 15.
Article in English | MEDLINE | ID: mdl-24007788

ABSTRACT

Considerable research has been done on the effects of endocrine disrupting chemicals (EDCs) on reproduction and gene expression in the brain, liver and gonads of teleost fish, but information on impacts to the pituitary gland are still limited despite its central role in regulating reproduction. The aim of this study was to further our understanding of the potential effects of natural and synthetic estrogens on the brain-pituitary-gonad axis in fish by determining the effects of 17α-ethynylestradiol (EE2) on the pituitary transcriptome. We exposed sub-adult coho salmon (Oncorhynchus kisutch) to 0 or 12 ng EE2/L for up to 6 weeks and effects on the pituitary transcriptome of females were assessed using high-throughput Illumina(®) sequencing, RNA-Seq and pathway analysis. After 1 or 6 weeks, 218 and 670 contiguous sequences (contigs) respectively, were differentially expressed in pituitaries of EE2-exposed fish relative to control. Two of the most highly up- and down-regulated contigs were luteinizing hormone ß subunit (241-fold and 395-fold at 1 and 6 weeks, respectively) and follicle-stimulating hormone ß subunit (-3.4-fold at 6 weeks). Additional contigs related to gonadotropin synthesis and release were differentially expressed in EE2-exposed fish relative to controls. These included contigs involved in gonadotropin releasing hormone (GNRH) and transforming growth factor-ß signaling. There was an over-representation of significantly affected contigs in 33 and 18 canonical pathways at 1 and 6 weeks, respectively, including circadian rhythm signaling, calcium signaling, peroxisome proliferator-activated receptor (PPAR) signaling, PPARα/retinoid x receptor α activation, and netrin signaling. Network analysis identified potential interactions between genes involved in circadian rhythm and GNRH signaling, suggesting possible effects of EE2 on timing of reproductive events.


Subject(s)
Ethinyl Estradiol/toxicity , Oncorhynchus kisutch/physiology , Pituitary Gland/drug effects , Transcriptome , Water Pollutants, Chemical/toxicity , Animals , Endocrine System/drug effects , Female , Follicle Stimulating Hormone/genetics , Gonads/drug effects , Luteinizing Hormone/genetics , Oncorhynchus kisutch/genetics
13.
PLoS One ; 8(7): e69615, 2013.
Article in English | MEDLINE | ID: mdl-23894510

ABSTRACT

Exploitation of fisheries resources has unintended consequences, not only in the bycatch and discard of non-target organisms, but also in damage to targeted fish that are injured by gear but not landed (non-retention). Delayed mortality due to non-retention represents lost reproductive potential in exploited stocks, while not contributing to harvest. Our study examined the physiological mechanisms by which delayed mortality occurs and the extent to which injuries related to disentanglement from commercial gear compromise reproductive success in spawning stocks of Pacific salmon (Oncorhynchus spp.). We found evidence for elevated stress in fish injured via non-retention in gillnet fisheries. Plasma cortisol levels correlated with the severity of disentanglement injury and were elevated in fish that developed infections related to disentanglement injuries. We also analyzed sex steroid concentrations in females (estradiol-17ß and 17,20ß-dihydroxy-4-pregnen-3-one) to determine whether non-retention impairs reproductive potential in escaped individuals. We demonstrate evidence for delayed or inhibited maturation in fish with disentanglement injuries. These findings have important implications for effective conservation and management of exploited fish stocks and suggest means to improve spawning success in such stocks if retention in commercial fisheries is improved and incidental mortality reduced.


Subject(s)
Fisheries , Fishes/blood , Fishes/injuries , Reproduction/physiology , Animals , Estradiol/blood , Female , Fishes/physiology , Hydrocortisone/blood , Hydroxyprogesterones/blood , Salmon/blood , Salmon/injuries , Salmon/physiology
14.
Dev Biol ; 372(2): 239-48, 2012 Dec 15.
Article in English | MEDLINE | ID: mdl-23022660

ABSTRACT

It has long been hypothesized that in fishes the contents of cortical granules are involved in the hardening of egg envelope following fertilization. We previously purified the egg envelope hardening initiation factor from the exudates released from activated medaka (Oryzias latipes) eggs and tentatively termed this protein alveolin. Alveolin is a member of the astacin metalloprotease family and was proposed to be a protease which hydrolyzes ZPB at one restricted position to allow starting cross-linking with ZPC. Here, we investigated the complete pathway from biosynthesis and accumulation to secretion of alveolin. A single alveolin transcript was detected only in ovarian preparations, confirming the specific expression of alveolin in the ovary. In situ hybridization indicated that the alveolin mRNA is already expressed in the very early previtellogenic oocytes. However, immunocytochemical studies revealed that the appearance of alveolin protein was delayed until the beginning of the vitellogenic stage. The cortical granules isolated from unfertilized eggs contained a high molecular weight form of glycosylated alveolin with a 50kDa relative molecular mass. Hypotonic treatment burst isolated granules in vitro and transformed alveolin to a 21.5kDa form, which is the same size as that of natural alveolin released from eggs upon fertilization. This transformation was inhibited in the presence of leupeptin and 4-(2-aminoethyl) benzenesulfonyl fluoride hydrochloride (AEBSF), suggesting that a serine protease is involved in alveolin activation upon fertilization. Furthermore, the phylogenetic relationship of alveolin with other vertebrate astacin family members was analyzed. The result shows that alveolin and its teleostean homologs make a new group which is separate from either the hatching enzyme, meprin and BMP1/tolloid groups.


Subject(s)
Fertilization , Metalloendopeptidases/metabolism , Oocytes/metabolism , Oryzias/metabolism , Animals , Female , Gene Expression Regulation, Developmental , Male , Metalloendopeptidases/genetics , Oocytes/cytology , Oocytes/enzymology , Oogenesis , Organ Specificity , Oryzias/anatomy & histology , Oryzias/genetics , Phylogeny , RNA, Messenger/genetics
15.
Biol Reprod ; 87(3): 64, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22674392

ABSTRACT

An in vitro system was used to analyze the effects of sex steroids on the development of primary (late perinucleolar stage) and early secondary, previtellogenic (early cortical alveolus stage) ovarian follicles of coho salmon cultured for up to 21 days. Late perinucleolar-stage follicles increased significantly in size after 7 days of treatment with low concentrations of 11-ketotestosterone (11-KT), a nonaromatizable androgen. An androgen receptor antagonist (flutamide) inhibited this growth-promoting effect, and the highest concentration resulted in atresia of follicles, implicating androgens as survival factors at this stage. Testosterone (T) was less effective than 11-KT in promoting growth, but blocking aromatization with exemestane resulted in a growth response similar to that of 11-KT. Estradiol-17beta (E2) had no effect on growth at this stage. After 21 days of culture, E2 was the most potent steroid in increasing the number of follicles containing cortical alveoli and the number of cortical alveoli within those follicles. At the early cortical alveolus stage, low doses of E2 promoted growth and strongly stimulated synthesis of cortical alveoli, actions that were inhibited by an estrogen receptor antagonist (tamoxifen). 11-KT displayed moderate growth-promoting effects, and 11-KT and T stimulated moderate to substantial increases in abundance of cortical alveoli. This study shows that the predominant role of androgens is the promotion of growth of late perinucleolar-stage follicles, while E2 stimulates both the growth and accumulation of cortical alveoli in early cortical alveolus-stage follicles.


Subject(s)
Androgens/pharmacology , Estradiol/pharmacology , Oncorhynchus kisutch , Ovarian Follicle/drug effects , Animals , Aromatase Inhibitors/pharmacology , Cell Culture Techniques , Cell Enlargement/drug effects , Cell Size/drug effects , Cells, Cultured , Female , Hormone Antagonists/pharmacology , Oncorhynchus kisutch/metabolism , Oncorhynchus kisutch/physiology , Ovarian Follicle/cytology , Ovarian Follicle/physiology , Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors , Time Factors
17.
Cent European J Urol ; 65(1): 51-2, 2012.
Article in English | MEDLINE | ID: mdl-24578928

ABSTRACT

A 31-year-old man with recurrent testicular torsion and infertility was found to have a fusional anomaly of the epididymis on scrotal exploration in which only the head of epididymis was attached to the testis, while the body and tail were completely free. He had bilateral orchidopexy, which relieved pain and recurrent torsion. He was then referred for fertility treatment. Literature search has shown that infertility is more associated with congenital anomalies of the epididymis and not with recurrent torsions.

18.
Reproduction ; 142(6): 869-77, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21976616

ABSTRACT

Gh plays important roles in development, somatic growth and gametogenesis in vertebrates. To determine the physiological role of Gh in reproduction in male teleosts, the expression of genes encoding Gh and the two Gh receptors (Ghrs) during spermatogenesis, and the action of Gh in vitro was examined using the Japanese eel (Anguilla japonica). gh, ghr1 and ghr2 mRNA transcripts were detected in all spermatogenic stages. In situ hybridization showed the presence of ghr1 and ghr2 mRNA in the germ cells. Immunohistochemistry using an antiserum against eel Gh indicated that Gh protein was localized to Sertoli cells surrounding the germ cells in early spermatogenesis. Recombinant eel Gh induced spermatogonial proliferation in a testis organ culture system, an effect that was independent from the production of steroid hormones or Igf1. This study identifies a role for eel Gh in the regulation of early spermatogenesis, particularly in the mitotic phase of spermatogenesis, that is not mediated by either steroid hormones or Igf1 production.


Subject(s)
Anguilla/metabolism , Growth Hormone/metabolism , Receptors, Somatotropin/metabolism , Spermatogenesis , Testis/metabolism , Animals , Cell Proliferation , Dihydrotestosterone/analogs & derivatives , Gonadal Steroid Hormones/metabolism , Insulin-Like Growth Factor I/metabolism , Male , RNA, Messenger/metabolism , Recombinant Proteins , Spermatogonia/physiology , Testosterone/analogs & derivatives
19.
Gen Comp Endocrinol ; 174(2): 156-65, 2011 Nov 01.
Article in English | MEDLINE | ID: mdl-21906597

ABSTRACT

The effects of chronic exposure to adrenocorticotropic hormone (ACTH) or the synthetic glucocorticoid dexamethasone (DEX) on the expression of genes involved in cortisol synthesis were examined using quantitative RT-PCR and immunohistochemistry. Juvenile Chinook salmon were treated with either ACTH via micro-osmotic pumps or with DEX via a lipid-based sustained release vehicle. Plasma cortisol levels were significantly elevated in ACTH-treated fish after 1 day, with a significant reduction in this effect with increasing treatment duration. ACTH also appeared to cause progressive hyperplasia of interrenal cells. Steroidogenic acute regulatory protein (StAR) and cytochrome P450 side chain cleavage enzyme (P450scc) transcripts but not 3ß-hydroxysteroid dehydrogenase-isomerase (3ß-HSD) or cytochrome P450 11ß-hydroxylase (P45011ß) transcripts in head kidneys significantly increased after 5 days of ACTH treatment. Significant linear relationships between plasma cortisol levels and transcript levels were identified at day 1 and day 5 for StAR, and day 5 for P450scc. Increased immunoreactivity for P450scc was observed in interrenal cells of ACTH-treated fish after 5 and 10 days. No effect of ACTH on 3ß-HSD immunoreactivity was apparent at any time point. P45011ß immunoreactivity was more intense after 5 days treatment with ACTH. DEX significantly reduced resting plasma cortisol levels and induced interrenal cell atrophy. Although no significant effect of treatment with DEX was found for any transcript, immunoreactivity for P450scc and P45011ß appeared to be reduced. These results indicate that StAR and P450scc are subject to transcriptional regulation by chronic changes in ACTH levels.


Subject(s)
Adrenocorticotropic Hormone/pharmacology , Phosphoproteins/metabolism , 3-Hydroxysteroid Dehydrogenases/genetics , 3-Hydroxysteroid Dehydrogenases/metabolism , Animals , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Gene Expression Regulation/drug effects , Immunohistochemistry , Phosphoproteins/genetics , Polymerase Chain Reaction , Salmon
20.
Retina ; 31(8): 1620-6, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21610564

ABSTRACT

PURPOSE: To estimate the usefulness of preferential hyperacuity perimetry (PHP) in detecting conversion of early to late age-related macular degeneration in the Carotenoids and co-antioxidants in patients with Age-Related Maculopathy, a multicenter randomized controlled clinical trial. METHODS: This was a nested case control study within the Carotenoids and co-antioxidants in patients with Age-Related Maculopathy (CARMA) clinical trial and included all participants enrolled in a single center (n = 200). Data are from participants who progressed to neovascular age-related macular degeneration (nvAMD) during time on study, Group 1 (n = 10) before the use of PHP and Group 2 (n = 10) during use of PHP. We also randomly selected 21 other participants (Group 3) who did not progress to nvAMD during time on study as a control group. Change in best-corrected visual acuity and contrast sensitivity and size of neovascular lesion at detection of conversion to nvAMD in Groups 1 and 2. RESULTS: At detection of nvAMD, mean best-corrected visual acuity in Group 1 was 57.5 letters versus 67.4 in Group 2. In Group 1, the change in best-corrected visual acuity from baseline to detection of nvAMD was twice that of Group 2 (21.6 ± 9.0 versus 11.9 ± 10.7) with a mean difference of 9.7 letters (95% confidence interval, 0.41 to 19.0, P = 0.04, independent-samples t-test). The size of the neovascular lesion at detection was 3.06 mm in Group 1 versus 0.89 mm in Group 2 (P = 0.02). Two thirds of the participants in Group 2 were asymptomatic at detection of nvAMD compared with one fifth in Group 1. Preferential hyperacuity perimetry distortion maps were abnormal in 9 of 10 eyes in Group 2, which were confirmed by optical coherence tomography. Of the 21 eyes in Group 3, PHP maps were normal in 18 and abnormal in 3. CONCLUSION: Preferential hyperacuity perimetry detected abnormalities in central visual function with high reliability. Eyes with nvAMD lesions detected by PHP had smaller lesions and better function when compared with the group before the introduction of PHP. The false-negative rate was <10% on PHP. The PHP distortion map was helpful in alerting clinicians to the presence of subclinical nvAMD.


Subject(s)
Tomography, Optical Coherence , Vision Disorders/diagnosis , Visual Acuity/physiology , Visual Field Tests , Wet Macular Degeneration/diagnosis , Antioxidants/administration & dosage , Ascorbic Acid/administration & dosage , Case-Control Studies , Double-Blind Method , False Negative Reactions , Humans , Lutein/administration & dosage , Predictive Value of Tests , Vision Disorders/drug therapy , Vision Disorders/physiopathology , Vitamin E/administration & dosage , Wet Macular Degeneration/drug therapy , Wet Macular Degeneration/physiopathology , Xanthophylls/administration & dosage , Zeaxanthins , Zinc/administration & dosage
SELECTION OF CITATIONS
SEARCH DETAIL
...