Novel oviduct endoscope combining optical coherence tomography with intratubal ultrasonography for fallopian tube exploration: An in vivo rabbit pilot study.

BACKGROUND AND STUDY AIM: Currently, several limitations exist in the examination of the oviduct. In this study, the usefulness and feasibility of a novel ultrafine dual-modality oviduct endoscopy device for in vivo assessment of the oviduct were evaluated. METHODS: Five Japanese white rabbits were selected to undergo oviduct probing using a combination of optical coherence tomography (OCT) and intratubal ultrasonography. The feasibility of the procedure was evaluated through 152 pairs of clear, clinically interpretable images obtained using spiral scanning via the pull-back method. OCT images were compared with the oviduct histopathology sections. RESULTS: Visualization of the oviduct using both OCT and ultrasound revealed a differentiated three-layer tissue; however, ultrasound showed a poorer clarity than OCT. By comparing OCT images with the histological morphology of the oviduct, the inner low-reflective layer of the oviduct corresponds to the mucosal layer, the middle high-reflective layer corresponds to the fibrous muscle layer, and the outer low-reflective layer corresponds to the connective tissue layer. Postoperatively, the general condition of the animals was good. CONCLUSION: This study demonstrated the feasibility and potential clinical value of the novel ultrafine dual-modality oviduct endoscope. Dual-modality imaging of OCT and intratubal ultrasonography can provide clearer microstructure of the oviduct wall.

In vivo dynamic 3D imaging of oocytes and embryos in the mouse oviduct.

Developmental biologists have always relied on imaging to shed light on dynamic cellular events. However, processes such as mammalian fertilization and embryogenesis are generally inaccessible for direct imaging. In consequence, how the oviduct (fallopian tube) facilitates the transport of gametes and preimplantation embryos continues to be unanswered. Here we present a combination of intravital window and optical coherence tomography for dynamic, volumetric, in vivo imaging of oocytes and embryos as they are transported through the mouse oviduct. We observed location-dependent circling, oscillating, and long-distance bi-directional movements of oocytes and embryos that suggest regulatory mechanisms driving transport and question established views in the field. This in vivo imaging approach can be combined with a variety of genetic and pharmacological manipulations for live functional analysis, bringing the potential to investigate reproductive physiology in its native state.

Incidence of malignant transformation in the oviductal fimbria in laying hens, a preclinical model of spontaneous ovarian cancer.

Ovarian high grade serous carcinoma (HGSC) is a lethal form of ovarian cancer (OVCA). In most cases it is detected at late stages as the symptoms are non-specific during early stages. Emerging information suggests that the oviductal fimbria is a site of origin of ovarian HGSC. Currently available tests cannot detect ovarian HGSC at early stage. The lack of a preclinical model with oviductal fimbria that develops spontaneous ovarian HGSC is a significant barrier to developing an early detection test for this disease. The goal of this study was to examine if the oviductal fimbria in hens is a site of origin of HGSC and whether it expresses several putative markers expressed in ovarian HGSC in patients. A total of 135 laying hens (4 years old) were selected from a flock using transvaginal ultrasound (TVUS) imaging, followed by euthanasia and gross examination for the presence of solid masses and ascites. Histological types of carcinomas were determined by hematoxylin and eosin staining. Expression of WT-1, mutant p53, CA-125, PAX2 and Ki67 in normal or malignant fimbriae or ovaries were examined using immunohistochemistry, immunoblotting and gene expression assays. This study detected tumors in oviductal fimbriae in hens and routine staining revealed ovarian HGSC-like microscopic features in these tumors. These tumors showed similarities to ovarian HGSC in patients in expressing several markers. Compared with normal fimbriae, intensities of expression of WT-1, mutant p53, CA-125, and Ki67 were significantly (P<0.05) higher in fimbrial tumors. In contrast, expression of PAX2 decreased gradually as the tumor progressed to late stages. The patterns of expression of these markers were similar to those in ovarian HGSC patients. Thus, tumors of the oviductal fimbria in hens may offer a preclinical model to study different aspects of spontaneous ovarian HGSC in women including its early detection.

In Vivo Imaging of the Mouse Reproductive Organs, Embryo Transfer, and Oviduct Cilia Dynamics Using Optical Coherence Tomography.

The oviduct (or fallopian tube) serves as the site where a number of major reproductive events occur for the start of a new life in mammals. Understanding the oviduct physiology is essential to uncover hidden mechanisms of the human reproduction and its disorders, yet the current analysis of the oviduct that is largely limited to in vitro imaging is a significant technical hurdle. To overcome this barrier, we have recently developed in vivo approaches based on optical coherence tomography for structural and functional imaging of the mouse oviduct. In this chapter, we describe the details of such live imaging methods that allow for three-dimensional visualization of the oviduct wall morphology, microscale mapping of the oviduct cilia beat frequency, and high-resolution observation of the cumulus-oocyte complex at the cellular level. We expect this set of imaging tools will enable novel studies toward a comprehensive knowledge of the mammalian reproduction.

Prolonged in vivo functional assessment of the mouse oviduct using optical coherence tomography through a dorsal imaging window.

The oviduct (or fallopian tube) serves as an environment for gamete transport, fertilization and preimplantation embryo development in mammals. Although there has been increasing evidence linking infertility with disrupted oviduct function, the specific roles that the oviduct plays in both normal and impaired reproductive processes remain unclear. The mouse is an important mammalian model to study human reproduction. However, most of the current analyses of the mouse oviduct rely on static histology or 2D visualization, and are unable to provide dynamic and volumetric characterization of this organ. The lack of imaging access prevents longitudinal live analysis of the oviduct and its associated reproductive events, limiting the understanding of mechanistic aspects of fertilization and preimplantation pregnancy. To address this limitation, we report a 3D imaging approach that enables prolonged functional assessment of the mouse oviduct in vivo. By combining optical coherence tomography with a dorsal imaging window, this method allows for extended volumetric visualization of the oviduct dynamics, which was previously not achievable. The approach is used for quantitative analysis of oviduct contraction, spatiotemporal characterization of cilia beat frequency and longitudinal imaging. This new approach is a useful in vivo imaging platform for a variety of live studies in mammalian reproduction.

Lateral Body Wall Herniation Involving the Oviduct in Two Psittacine Birds.

Lateral body wall herniation with involvement of the oviduct was diagnosed in a female nanday conure (Aratinga nenday) and a female eclectus parrot (Eclectus roratus). A history of chronic egg laying and chronic reproductive activity was reported in both cases. A subcutaneous mass in the area of the caudal left lateral body wall was present in both birds. Diagnostic imaging (ultrasonography, computed tomography) and cytologic examination lead to the diagnosis of left lateral body wall herniation with involvement of the oviduct. In the conure, a developing egg was contained within the herniated oviduct. Both cases were successfully treated by salpingohysterectomy and surgical correction of the hernal ring. Lateral body wall herniation with oviductal involvement in birds has not previously been reported and should be considered as a differential for birds presenting with masses originating from the lateral body wall.

In vivo micro-scale tomography of ciliary behavior in the mammalian oviduct.

Motile cilia in the mammalian oviduct play a key role in reproduction, such as transporting fertilized oocytes to the uterus for implantation. Due to their small size (~5-10 µm in length and ~300 nm in diameter), live visualization of cilia and their activity in the lumen of the oviduct through tissue layers represents a major challenge not yet overcome. Here, we report a functional low-coherence optical imaging technique that allows in vivo depth-resolved mapping of the cilia location and cilia beat frequency (CBF) in the intact mouse oviduct with micro-scale spatial resolution. We validate our approach with widely-used microscopic imaging methods, present the first in vivo mapping of the oviduct CBF in its native context, and demonstrate the ability of this approach to differentiate CBF in different locations of the oviduct at different post-conception stages. This technique opens a range of opportunities for live studies in reproductive medicine as well as other areas focused on cilia activity and related ciliopathies.

Follistatin is essential for normal postnatal development and function of mouse oviduct and uterus.

Female mice lacking the follistatin gene but expressing a human follistatin-315 transgene (tghFST315) have reproductive abnormalities (reduced follicles, no corpora lutea and ovarian-uterine inflammation). We hypothesised that the absence of follistatin-288 causes the abnormal reproductive tract via both developmental abnormalities and abnormal ovarian activity. We characterised the morphology of oviducts and uteri in wild type (WT), tghFST315 and follistatin-knockout mice expressing human follistatin-288 (tghFST288). The oviducts and uteri were examined in postnatal Day-0 and adult mice (WT and tghFST315 only) using histology and immunohistochemistry. Adult WT and tghFST315 mice were ovariectomised and treated with vehicle, oestradiol-17ß (100ng injection, dissection 24h later) or progesterone (1mg×three daily injections, dissection 24h later). No differences were observed in the oviducts or uteri at birth, but abnormalities developed by adulthood. Oviducts of tghFST315 mice failed to coil, the myometrium was disorganised, endometrial gland number was reduced and oviducts and uteri contained abundant leukocytes. After ovariectomy, tghFST315 mice had altered uterine cell proliferation, and inflammation was maintained and exacerbated by oestrogen. These studies show that follistatin is crucial to postnatal oviductal-uterine development and function. Further studies differentiating the role of ovarian versus oviductal-uterine follistatin in reproductive tract function at different developmental stages are warranted.

Usefulness of 11C-choline positron emission tomography for genital chlamydial infection assessment in a BALB/c murine model.

PURPOSE: The aim of this study is to explore the feasibility of 11C-Choline PET in the assessment of the degree of inflammation in the Chlamydia muridarum genital infection model. PROCEDURES: Forty female Balb/c mice received 2.5 mg of medroxyprogesterone acetate i.m. 9 and 2 days prior to the infection: 21 mice were infected by C. muridarum into the vaginal vault, 12 mice were treated with inactivated chlamydiae, and 7 mice were SPG buffer-treated as negative controls. Three healthy control mice were not treated with progesterone. Mice in each category were randomly subdivided in two groups: (1) sacrificed at 5, 10, 15, and 20 days for histological analysis and (2) undergoing 11C-Choline PET at days 5, 10, and 20 post-infection (20 MBq of 11C-Choline, uptake time of 10 min, acquisition through a small-animal PET tomograph for 15 min). RESULTS: Infected animals showed a significantly higher standardized uptake value than both controls and animals inoculated with heat-inactivated chlamydiae in each PET scan (P<0.05). All organs of the infected animals had scores of inflammation ranging between 2 and 3 at day 5, decreasing to 1-2 at day 20. CONCLUSIONS: This preliminary result demonstrated that 11C-Choline PET can highlight a specific proliferation mechanism of inflammatory cells induced by C. muridarum, thanks to a very high sensitivity in detecting very small amounts of tracer in inflammatory cells.

Superconception in mammalian pregnancy can be detected and increases reproductive output per breeding season.

The concept of superfetation, a second conception during pregnancy, has been controversial for a long time. In this paper we use an experimental approach to demonstrate that female European brown hares (Lepus europaeus) frequently develop a second pregnancy while already pregnant and thereby increase their reproductive success. After a new, successful copulation, we confirmed additional ovulations before parturition in living, late-pregnant females by detecting a second set of fresh corpora lutea using high-resolution ultrasonography. The presence of early embryonic stages in the oviduct, demonstrated by oviduct flushing, next to fully developed fetuses in the uterus is best explained by passage of semen through the late-pregnant uterus; this was confirmed by paternity analysis using microsatellite profiling. Subsequent implantation occurred after parturition. This superfetation, categorized as superconception, significantly increased litter size and permitted females to produce up to 35.4% more offspring per breeding season. It is therefore most likely an evolutionary adaptation.

Ultrasonography of reproductive structures and hormonal correlates of follicular development in female American alligators, Alligator mississippiensis, in southwest Louisiana.

Ultrasonography has been used effectively to study reproduction in a variety of reptile species, but its application to crocodilians has been relatively limited. We present results from a study testing the efficacy of using ultrasonography to monitor reproduction in the American alligator, Alligator mississippiensis. Ultrasound results were then compared with plasma hormone levels. A total of 124 females were examined during March, April, May, and early June (2001-2003). Ultrasound results were validated on a series of reproductive females (n=14) necropsied for other studies. Previtellogenic follicles, vitellogenic follicles, recently shelled eggs, fully developed well-calcified eggs, and atretic follicles were readily discernible with ultrasound in mature females. Reproductive structures were observed in 57 females of which 43 were actively reproductive, while 14 were non-reproductive, but contained large atretic follicles from prior years. Oviducts were discernible in females with eggs. Ovarian state was also correlated with hormone levels. These results are in agreement with previous studies that showed that 50% or less of the adult female alligator population is reproductively active in a given year. Ultrasonography can be used to make an accurate assessment of reproductive condition in wild alligator populations.

The relation between ultrasonographic observations in the oviduct and plasma progesterone, luteinizing hormone and estradiol during the egg laying cycle in ostriches.

In this study we investigated the temporal relationship between ovulation, egg formation, oviposition and the changes in plasma concentrations of progesterone, luteinizing hormone and estradiol-17beta during the egg laying cycle in farmed ostriches. In 10 egg-producing birds, transcutaneous ultrasound scanning was performed at 3h intervals and blood sampling at hourly intervals during a period of at least 48h (one egg laying cycle). In hens (n=8) that ovulated during the observational period, the ovulated egg was first detected 2h after oviposition; thus, ovulation occurred shortly after oviposition in all birds. During the period between two consecutive ovipositions, the developing egg remained for 9h in the proximal part (infundibulum, magnum or isthmus) and for 39h in the distal part of the oviduct (uterus). In ovulating hens, plasma progesterone concentrations showed a characteristic and consistent profile: from basal levels of around 0.1ng/ml concentrations started to increase 12h before oviposition, reached an average maximum of 3.5ng/ml at 3h before oviposition and returned to basal levels 3h and 30min after oviposition. Changes in plasma luteinizing hormone and estradiol-17beta concentrations showed comparable patterns of elevation and decline relative to the timing of oviposition and ovulation. However, variation in their individual basal concentrations was generally larger and peak values were less conspicuous than those of progesterone. In non-ovulating hens (n=2) neither progesterone, nor luteinizing hormone nor estradiol-17beta showed elevations to peak concentrations before oviposition. These data demonstrate that during the egg laying cycle of ostriches, events such as ovulation, egg development and oviposition evolve according to a rather strict time schedule, and that progesterone, luteinizing hormone and estradiol-17beta reach peak concentrations shortly before ovulation. Additionally, our findings also show that on-farm ultrasound scanning is a useful technique to discriminate between ovulating and non-ovulating hens.

Observations on the significance of diagnostic findings in egg-binding of Psittaciformes.

Clinical examination of 2192 psittacine birds of both sexes revealed a prevalence of 2.74 per cent (60 birds) of egg-binding. Domesticated species easily bred in captivity were the most commonly affected; the prevalence in cockatiels (15.75 per cent), and in budgerigars (5.73 per cent). An accurate diagnosis was possible in all cases by means of an evaluation of the case history, a visual examination, palpation and radiographic and ultrasonographic examinations. The case history alone was typical in 60 per cent of the cases, and reliable diagnosis was reached with the help of a visual examination in 70 per cent of the cases. Radiographic examination provided a definitive diagnosis in 30 per cent of the cases, especially in those with shelled eggs. Medullary bone proved to be a radiographic indication of laminated and thin-shelled eggs. However, laminated and thin-shelled eggs could only be differentiated definitively from abdominal masses, salpingitis and cystic degeneration by means of ultrasonography.

Induced hydrosalpinges in rabbits: comparison of hysterosalpingographic media and development of an animal model.

Experiments were conducted in rabbits to test the effect of commonly used hysterosalpingographic media on tubal structure and function. A model of hydrosalpinx was created by ligating both ends of the oviduct, and the lumen was filled with test solutions. Three groups of animals were studied. Group 1 rabbits (operated controls) received Hanks' balanced salt solution or no solution. In the second group (unoperated controls), no solution or occlusive ligature was applied. Group 3 received either Ethiodol (Savage Laboratories, Missouri City, TX), an oil-soluble contrast medium (OSCM), or Sinografin (E.R. Squibb & Sons, Princeton, NJ), a water-soluble contrast medium (WSCM). Histopathologic changes in the endosalpinx were moderate in the doubly ligated oviducts, and no difference was found between the effects of OSCM and WSCM in group 3 or between groups 1 and 3. Ciliary transport rate on the ampullary endosalpinx of group 1 was 0.05 mm/second, i.e., half the normal rate in the unoperated controls (P less than 0.001) and OSCM-filled oviducts (P less than 0.01). The rate in WSCM oviducts was 0.01 mm/second, significantly slower than in the OSCM-filled oviducts (P less than 0.05).