Thesis (M. Med. Sc.)--University of Hong Kong, 2005.

Thesis (M. Med. Sc.)--University of Hong Kong, 2006.

Thesis (M. Med. Sc.)--University of Hong Kong, 2006.

Although pregnant viviparous squamates are sometimes claimed to be able to resorb inviable eggs and embryos from the uterus, definitive evidence for such resorption is not available. After placing pregnant female Pseudemoia pagenstecheri into conditions under which embryonic development is terminated, we periodically harvested the gravid oviducts and examined them histologically. Females contained abnormal and degenerating eggs and embryos that had died in various stages of development. Dead embryos had undergone extensive cytolysis, dissolution, and aseptic necrosis and vitelline masses showed signs of deterioration and passage down the oviduct. The uterine mucosa lay in direct contact with the vitelline material, with no intact shell membrane intervening between them. Yolk was sometimes displaced into the exocoelom and allantoic cavity due to rupture of the extraembryonic membranes. Histological examination revealed no evidence of the uptake of yolk by the uterine epithelium or its accumulation in the subepithelial connective tissue. In many specimens, the uterine epithelium showed minuscule, apical granules. The position, appearance, and staining properties of the granules suggests them to be secretory, a manifestation of placentotrophy. Our observations indicate that P. pagenstecheri females retain dead eggs and embryos for several weeks or longer, yet do not resorb them during that period. This lizard is the second placentotrophic skink species in which resorption has been suspected, but in which abortive eggs appear to be retained or extruded instead of being resorbed by the oviducts. Researchers should not assume that squamates can digest and resorb oviductal eggs without definitive morphological evidence.

The female reproductive system of the humpbacked fly Megaselia scalaris Loew (Diptera : Phoridae) was examined in whole mount preparations and serial sections. The system includes 2 ovaries, paired lateral oviducts, a common oviduct, and a genital chamber, opening externally through a gonopore, anteriad and ventrad to the anus. The ducts of the 2 accessory glands open independently into the dorsal region of the genital chamber. The terminal duct of a 2-armed spermatheca joins the right posterior and ventral wall of the genital chamber, immediately inside the gonopore. Passing dorally, the spermathecal duct lies immediately ventral to the duct of the right accessory gland. A short distance posteriad, it divides into two branches, each supplying an arm of the spermatheca. The genital chamber extends both anteriorly and posteriorly from its junction with the common oviduct, creating anterior and posterior compartments. In the right lateral wall of the genital chamber, a distinctive loop-shaped thickening (plate) resembles a darkened thread when it is observed through the integument. Features likely to have taxonomic utility include the posterior and ventral location of the terminal portion of the spermathecal duct; and the asymmetrically arranged, loop-shaped plate.

Indiana University-Purdue University Indianapolis (IUPUI) / Progression of Chlamydia into upper reproductive tract epithelium and the induction of subsequent immune responses to infection are major contributors to Chlamydia-induced pathogenesis of the genital tract. We reported that C. muridarum infection of the oviduct epithelial cells (OEs) secrete IFN-β in a TLR3 dependent manner. However, we showed that the C. muridarum infected TLR3-deficient OEs were still able to secrete minimal amounts of IFN-β into the supernatants, which is suggestive that there are other signaling pathways that contribute to Chlamydia-induced IFN-β synthesis in these cells. Previous studies describing the activation of the JAK/STAT signaling pathway during Chlamydia infection of cervical epithelial cells proposes a putative role for STAT1 in the synthesis of type I IFNs during Chlamydia infection. The present study investigated the role of STAT1 in Chlamydia-induced IFN-β production in OEs. OEs were infected with Chlamydia muridarum and analyzed at 24 hours by RT-PCR and western blot to determine STAT1 expression. STAT (-/-) OEs were infected and IFN-β production measured by ELISA. Quantitative real-time PCR analyses were performed at 6 and 16 hour post-infection to elucidate the mechanisms involved in IFN-β production during infection. Fluorescent microscopy was used to observe changes in Chlamydia replication. STAT1 activation and expression were significantly increased in wild-type (WT) OEs upon infection. TLR3 (-/-) OEs showed diminished STAT1 protein activation and expression. Augmented STAT1 protein expression corresponded to STAT1 mRNA levels. ELISA analyses revealed significantly less IFN-β production in infected STAT1 (-/-) OEs compared to WT OEs. Quantitative real-time PCR data showed that gene expression of IFN-β and of type I IFN signaling components were significantly increased during late stage Chlamydia infection, dependent on STAT1. Temporal regulation and increases in expression of IFN-α subtypes during infection were STAT1-dependent. Our results implicate STAT1-mediated signaling as a contributor to the C. muridarum-induced synthesis of IFN-β and other type I IFNs in OEs. We previously described a major role for TLR3 in the early-stage Chlamydia-induced synthesis of IFN-β in OEs; the results from this study suggest a role for STAT1 in the synthesis of type I IFNs that occurs during early and late stages of infection.

Internal fertilization occurs in birds and eutherian mammals. Foetal development, however, is either extra- respectively intra-corpore (egg vs uterus). In these animal classes, the female genital tract stores ejaculated spermatozoa into a restricted oviductal segment; the functional pre-ovulatory sperm reservoir, where they survive until ovulation/s occur. Paradoxically, this immunologically foreign sperm suspension in seminal fluid/plasma, often microbiologically contaminated, ought to be promptly eliminated by the female local immune defence which, instead, tolerates its presence. The female immune tolerance is presumably signalled via a biochemical interplay of spermatozoa, as well as the peptides and proteins of the extracellular seminal fluid, with female epithelial and immune cells. Such interplay can result in gene expression shifts in the sperm reservoir in relation to variations in fertility. To further aid our understanding of the underlying mechanisms, this thesis studied the proteome of the seminal fluid (using 2D SDS-PAGE and mass spectrometry) including cytokine content (using Luminex and/or ELISA) of healthy, sexually mature and fertile boars and cocks. As well, gene expression changes (using cDNA microarray) in the oviductal sperm reservoirs of sexually-mature females, mated or artificially infused with homologous sperm-free seminal fluid/plasma were studied. Pigs were of commercial, fertility-selected modern breeds (Landrace), while chicken belonged to the ancestor Red Junglefowl (RJF, low egg laying-capacity), a selected egg-layer White Leghorn (WL) and of their Advanced Intercross Line (AIL). Ejaculates were manually collected as single sample in cocks or as the sperm-rich fraction [SRF] and the post- SRF fraction in boars to harvest seminal fluid/plasma for proteome/cytokine and infusion-studies. Oviducts were retrieved for gene-expression analyses via microarray immediately post-mortem (chicken) or at surgery (pig), 24 h after mating or genital infusion. In pigs, the protein-rich seminal plasma showed the highest amounts of cytokines [interferon-γ, interferon gamma-induced protein 10 (IP-10/CXCL10), macrophage derived chemokine (MDC/CCL22), growth-regulated oncogene (GRO/CXCL1), granulocyte-macrophage colony-stimulating factor (GM-CSF), monocyte chemo-attractant protein-1 (MCP-1/ CCL2), interleukin (IL)-6, IL-8/CXCL8, IL-10, IL-15, IL-17 and transforming growth factor (TGF)-β1-3) in the larger, protein-rich and sperm-poor post-SRF, indicating its main immune signalling influence. Chicken showed also a plethora of seminal fluid proteins with serum albumin and ovotransferrin being conserved through selection/evolution. However, they showed fewer cytokines than pigs, as the anti-inflammatory/immune-modulatory TGF-β2 or the pro-inflammatory CXCL10. The RJF contained fewer immune system process proteins and lacked TGF-β2 compared to WL and AIL, suggesting selection for increased fertility could be associated with higher expression of immune-regulating peptides/proteins. The oviductal sperm reservoir reacted in vivo to semen exposure. In chicken, mating significantly changed the expression of immune-modulatory and pH-regulatory genes in AIL. Moreover, modern fertile pigs (Landrace) and chicken (WL), albeit being taxonomically distant, shared gene functions for preservation of viable sperm in the oviduct. Mating or SP/SF-infusion were able to change the expression of comparable genes involved in pH-regulation (SLC16A2, SLC4A9, SLC13A1, SLC35F1, ATP8B3, ATP13A3) or immune-modulation (IFIT5, IFI16, MMP27, ADAMTS3, MMP3, MMP12). The results of the thesis demonstrate that both mating and components of the sperm-free seminal fluid/plasma elicit gene expression changes in the pre-ovulatory female sperm reservoir of chickens and pigs, some conserved over domestication and fertility-selection.

O desenvolvimento da técnica de transferência embrionária no oviduto mediante videolaparoscopia e a avaliação de produtividade da punção folicular laparoscópica (LOPU) associada à transferência embrionária laparoscópica e/ou por laparotomia videoassistida, ambas no oviduto, foram os objetivos do presente trabalho. Foram utilizados 53 animais, sendo as punções foliculares para obtenção dos oócitos realizadas em 9 ovelhas adultas estimuladas hormonalmente, chamadas doadoras. Os oócitos foram obtidos através de LOPU repetidamente com intervalo mínimo de um mês entre os procedimentos nas mesmas doadoras. Os oócitos puncionados foram maturados, fertilizados e mantidos em cultivo por até três. Os embriões clivados foram transferidos no segundo dia após a fertilização in vitro (FIV) em ovelhas receptoras com cio sincronizado. A transferência dos embriões (TE) foi realizada primeiramente em 10 receptoras por laparoscopia e em 34 receptoras por laparotomia videoassistida, sendo esta última dividida em duas etapas cronológicas. Para a realização da TE por videolaparoscopia, foi introduzido, inicialmente, um trocarte de 5 mm na linha média ventral próximo à glândula mamária para passagem da óptica. Um segundo portal, crânio-lateral ao primeiro, foi criado para introdução de pinça de manipulação de ovário. Confirmada a existência de corpo lúteo (CL) em um dos ovários, um trocarte foi inserido no lado oposto a esse para passagem de cateter de Foley. Sua função foi auxiliar na exposição e abertura da fímbria. Um cateter urinário, contendo os embriões foi então introduzido na porção inicial do oviduto para deposição dos mesmos. Obteve-se 8 fetos resultantes da transferência por laparoscopia (10 receptoras), 10 fetos resultantes da primeira etapa da transferência por laparotomia (14 receptoras) e 30 fetos resultantes da segunda etapa da laparotomia (20 receptoras). A média de fetos por sessão de LOPU foi de 1 para transferência laparoscópica, 1,3 na primeira etapa da transferência por laparotomia e 3,3 na segunda etapa de laparotomia. A transferência embrionária videolaparoscópica de embriões clivados no oviduto mostrou resultado positivo na produção de fetos, podendo ser considerada técnica promissora. Quando associada à LOPU, a transferência embrionária no oviduto por laparoscopia / laparotomia videoassistida, apresentou resultados superiores aos relatados na literatura com a transferência intra-uterina de embriões FIV. / The development of the technique of embryo transfer in oviduct through video-assisted laparoscopy and the demonstration of productive association between laparoscopic follicle aspiration (LOPU) and embryonic transfer laparoscopy and / or open surgery (video-assisted laparotomy)both in oviduct was the goal of the work. From the 53 animals used in the study, follicular puncture was used to obtain oocytes from 9 adult ewes for super-ovulated with hormonally stimulation, referred to as the donors. The oocytes were obtained through repeated LOPU with minimum intervals of one month from the same donor. The retrieved oocytes were matured, fertilized with frozen semen and cultured in vitro for up to two days after IVF. The cleaved embryos were transferred on the second day after IVF into synchronized receptor ewes. The transfer of embryos was first done in 10 receptors through laparoscopy and then in 34 receptors through video-assisted laparotomy, the latter being divided into two chronological stages. For the development of ET by video-assisted laparoscopy, a 5mm trocar was initially introduced ventral midline near the mammary gland for passage of the laparoscope. A second portal, in a craniolateral position was used for passage of another 5 mm trocar for introduction of forceps to manipulate the ovary. After confirming the existence of CL in one of the ovaries, a trocar was inserted on the opposite side for passage of the Foley catheter, to assist in the exposure and opening of the fimbria. A urinary catheter, containing the embryo, was then introduced into the initial portion of the oviduct for deposition of the embryos. There were 8 fetuses resulting from the transfer by laparoscopy (10 receptors), 10 fetuses resulting from the first stage of the transfer by laparotomy (14 receptors) and 30 fetuses resulting from the second stage of the laparotomy (20 receptors). The average number of fetuses per session of LOPU was 1 for laparoscopic transfer, 1.3 for the first stage of the transfer by laparotomy and 3.3 in the second stage of laparotomy. The technique of embryo transfer through video-assisted laparoscopy with cleaved embryos in oviduct was thus shown to a positive fetus\'s result of production, and will be promising. When associated with LOPU, the transfer of embryos in oviduct by laparoscopy / video-assisted laparotomy presented better results then other authors when compare intrauterine IVF embryo transfer.

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

Progestagenic compounds are emerging contaminants found in surface and ground water around the world. Information on the effects and potency of progestagens is needed in order to understand the environmental risks posed by these compounds. Using the Xenopus (Silurana) tropicalis test system, developmental and reproductive toxicity after exposure to selected progestagens were determined. Larval exposure to levonorgestrel (LNG) severely impaired oviduct and ovary development causing sterility. No effects on testicular development, spermcount or male fertility were observed. Hepatic mRNA expression of the androgen receptor was increased in the females indicating that the receptor is involved in LNG-induced developmental reproductive toxicity. Exposure of adult females to LNG, norethindrone (NET) or progesterone (P) increased the proportions of previtellogenic oocytes and reduced the proportions of vitellogenic oocytes compared with the controls, indicating an inhibited vitellogenesis. The effects on oocyte development were ascertained at environmentally relevant concentrations of LNG, NET and P (1.3, 1 and 10 ng/L respectively). Since unintentional co-exposure of progestagens and ethinylestradiol (EE2) occurs in wildlife and also in human infants, data on mixture effects of combined exposures to these hormones during development are needed. Co-exposure during development showed antagonistic effects of EE2 and LNG. EE2 caused a female biased sex ratio which showed a tendency to be antagonized by LNG. Moreover, the hepatic AR induction by LNG was counteracted by co-exposure to EE2. In conclusion, the results show that female amphibians are susceptible to reproductive toxicity of progestagens after developmental exposure as well as after adult exposure during the breeding period. The differentiating Müllerianduct and ovary, and the egg development are sensitive targets for progestagens. Finally, the findings reported in this thesis show that environmental progestagens impairs reproductive function in amphibians and may present a threat to reproduction in wild populations.