Infundibulum Research Articles

The Double-Stranded RNA Analog, Poly(I:C), Triggers Distinct Transcriptomic Shifts in Keratinocyte Subsets

IFN-1 responses during viral infections activate host-protective immunity, but it may also trigger autoimmune cascades in lupus erythematosus and psoriasis (Illescas-Montes et al., 2019; Wang et al., 2021). Aspects of antiviral immunity can be modeled in mice through the intraperitoneal injection of the double-stranded RNA analog, poly(I:C), which provokes systemic IFN-1 production (Kühn et al., 1995). Utilizing this approach, we recently reported that innate epithelial barrier during a IFN-1 response was bolstered by ADAM10‒Notch signaling pathway in upper hair follicles, infundibulum (IFD), and isthmus (ISM) (Sakamoto et al., 2021).

A Methodology to Assess Subregional Geometric Complexity for Tetralogy of Fallot Patients

Abstract During surgical repair of tetralogy of fallot (TOF), pulmonary valve preservation (preservative repair) has demonstrated improved long-term outcomes compared to repairs that incise into the valve annulus (nonpreservative repair). Given the influence of geometry on hemodynamics, the success of preservative repair may be linked to the suitability of the preoperative patient geometry. However, the specific patient anatomies that may be predisposed to successful preservative repair are unknown due to significant interpatient variability in right ventricular outflow tract (RVOT) and pulmonary artery geometries, as well as the limitations in current methods of subregional geometric analysis. As a first step toward understanding the link between geometry and hemodynamics in TOF patients at a subregion level, we characterize the TOF geometry from the right ventricular infundibulum (INF) to the left and right pulmonary arteries. Our process consists of segmentation of magnetic resonance (MR) images and analysis of cross-sectional slices of the geometries along the centerlines. For the INF, main, left, and right pulmonary arteries individually, we quantify geometric parameters important in determining hemodynamic characteristics such as flow separation and recirculation, which can influence the degree of regurgitation. Specifically, we calculate the diameter along the subregion length, the average diameter, length, and tortuosity for each segment, as well as the bifurcation, left pulmonary artery (LPA) and right pulmonary artery (RPA) branch angles. This approach enables direct geometric comparisons within and among patients and allows for observation of the range in anatomic presentation. We have applied this approach to a dataset of 11 postoperative TOF patients, repaired with both preservative and nonpreservative surgical techniques.

Molecular signatures of epithelial oviduct cells of a laying hen (Gallus gallus domesticus) and quail (Coturnix japonica)

BackgroundIn this work we have determined molecular signatures of oviduct epithelial and progenitor cells. We have proposed a panel of selected marker genes, which correspond with the phenotype of oviduct cells of a laying hen (Gallus gallus domesticus) and quail (Coturnix japonica). We demonstrated differences in characteristics of those cells, in tissue and in vitro, with respect to different anatomical and functional parts of the oviduct (infundibulum (INF), distal magnum (DM, and proximal magnum (PM)). The following gene expression signatures were studied: (1) oviduct markers (estrogen receptor 1, ovalbumin, and SPINK7 - ovomucoid), (2) epithelial markers (keratin 5, keratin 14, and occludin) and (3) stem-like/progenitor markers (CD44 glycoprotein, LGR5, Musashi-1, and sex determining region Y-box 9, Nanog homebox, OCT4/cPOUV gene encoding transcription factor POU5F3).ResultsIn chicken, the expression of oviduct markers increased toward the proximal oviduct. Epithelial markers keratin14 and occludin were high in distal oviduct and decreased toward the proximal magnum. In quail oviduct tissue, the gene expression pattern of oviduct/epithelial markers was similar to chicken. The markers of progenitors/stemness in hen oviduct (Musashi-1 and CD44 glycoprotein) had the highest relative expression in the infundibulum and decreased toward the proximal magnum. In quail, we found significant expression of four progenitor markers (LGR5 gene, SRY sex determining region Y-box 9, OCT4/cPOUV gene, and CD44 glycoprotein) that were largely present in the distal oviduct. After in vitro culture of oviduct cells, the gene expression pattern has changed. High secretive potential of magnum-derived cells diminished by using decreased abundance of mRNA. On the other hand, chicken oviduct cells originating from the infundibulum gained ability to express OVM and OVAL. Epithelial character of the cells was maintained in vitro. Among progenitor markers, both hen and quail cells expressed high level of SOX9, LGR5 and Musashi-1.ConclusionAnalysis of tissue material revealed gradual increase/decrease pattern in majority of the oviduct markers in both species. This pattern changed after the oviductal cells have been cultured in vitro. The results can provide molecular tools to validate the phenotype of in vitro biological models from reproductive tissue.

Immunocytochemical study of rhodopsin-containing putative encephalic photoreceptors in house sparrow, Passer domesticus

In seasonally breeding birds, encephalic photoreceptors (EPs) play an important role in regulating photoperiodic gonadal responses. Multiple photopigments have been suggested as the putative EPs, including rhodopsin, melanopsin, VA opsin and the cryptochromes. As for rhodopsin, two potential brain sites, the lateral septum (SL) and the infundibulum (INF) have been reported to co-express rhodopsin immunoreactivity (rhodopsin-ir) with vasoactive intestinal polypeptide immunoreactivity (VIP-ir) in groups of cerebrospinal fluid-contacting (CSF) cells, hypothesized to be the EPs for gonadal responses. In order to confirm the presence of rhodopsin in seasonally breeding birds and examine whether these EPs show daily change as do the photopigments in the retina and pineal gland, the present study immunocytochemically investigated: (1) the presence of rhodopsin expression in the deep brain of the house sparrow, Passer domesticus maintained in short days, and (2) rhythmic expression of rhodopsin and VIP in both SL and INF at Zeitgeber time (ZT) 1 and ZT 17 in house sparrows. Rhodopsin-ir and VIP-ir were observed in both areas of sparrow brains as previously described in other avian species but with a novel rod-like rhodopsin-ir cell type in the INF and novel expression of rhodopsin-ir fiber close to the preoptic area. Daily changes of rhodopsin-ir and VIP-ir cell number were revealed in the INF, but not in the SL. More rhodopsin-ir and fewer VIP-ir cells were found at ZT 17 than at ZT 1. In the median eminence, rhodopsin-ir fibers were only observed at ZT 1, and the relative optic density (ROD) of VIP-ir fibers was higher at ZT 1 than ZT 17. The results indicate daily changes of EPs in the IN and ME, suggesting a role of EPs in the orchestration of photoperiodic gonadal recrudesence.

Morphological changes and proliferative activity in the oviductal epithelium during hormonally defined stages of the oestrous cycle in the bitch.

The aim of the present study was to investigate morphological changes and proliferative activities in the epithelium of the canine oviduct with regard to the part of the oviduct - possibly indicating the existence of a locally restricted sperm reservoir - and the stage of the oestrous cycle. Nine healthy adult nulliparous bitches were submitted to ovariohysterectomy at three stages of the cycle: anoestrus (n = 3), late follicular phase (n = 3) and mid-luteal phase (n = 3). The whole oviduct ranging from the utero-tubal junction (UTJ) to the infundibulum (IN) was collected, divided into UTJ, IN plus six segments of equal length, i.e. eight oviductal specimens per animal were studied by light microscopy. Morphological characteristics of ovaries and endometrium were recorded macroscopically and verified histologically. The height of oviduct epithelial cells and percentage of ciliated cells (CC) were assessed and the respective data analysed statistically. Proliferative activity was immunohistochemically visualized by means of Ki-67 antigen detection. Blood was collected and concentrations of oestradiol-17beta and progesterone (P(4)) were measured. Within the IN and five of the six tissue samples collected from the ampulla and isthmus in anoestrous bitches, the oviductal surface epithelium consisted of low cuboidal cells demonstrating a uniform dark staining intensity. Only a very few scattered lighter staining CC could be detected. Under the influence of oestrogens during late follicular phase, the oviductal epithelium was highly differentiated. Lighter stained CC with apically located nuclei were easily distinguishable from basophilic secretory cells with apical cytoplasmic protrusions. Cell height and percentage of CC were significantly higher than in anoestrus (p <or= 0.05). During mid-luteal phase, high levels of P(4) were associated with differentiated and dedifferentiated cells as well as cells in regression seen in the mucosal folds of all samples. The percentage of CC and cell height were significantly lower than during late follicular phase (p <or= 0.05). Further signs of dedifferentiation consisted of a loss of cilia, a pinching off of the apical cytoplasm as well as the presence of debris and macrophages within the oviductal lumen. In the oviductal part of UTJ and the caudal isthmus hormone-dependent variations in cellular morphology were less distinct. Changes in cell height were minimal and did not differ significantly throughout the oestrous cycle. Hypertrophic cells with large nuclei were predominantly present at these sites, but did not consistently demonstrate signs of ciliation or secretion. Sporadic proliferating activity, visualized by means of Ki-67 antigen, was mainly seen in some cells of the late follicular phase samples. Thus, overall proliferative activity is generally very low or may occur within a relatively short period of time. It therefore cannot be excluded, that periods exhibiting higher mitotic rates are not included in the present study. It should, however, be mentioned that cells demonstrating morphological signs of apoptosis can only be seen very sporadically within a few specimens during mid-luteal phase, thus, reflecting low proliferative capacities and minimal cellular turnover found during this study. The results of the present study strongly indicate that oestrogens cause hypertrophy and differentiation, whereas P(4) induces gradual dedifferentiation or regression of the oviductal epithelium. Furthermore, they reveal clearly visible changes in the morphology of the tubal epithelium during the oestrous cycle. Depending on the tubal segment, these are, however, variably expressed. Whether the low degree of cellular variation of the UTJ and caudal isthmus is caused by specific hormone concentrations at these sites or specific regulatory mechanisms and may be associated with specific functional properties such as the formation of a locally restricted sperm reservoir needs further investigations.

Changes in Brain Gonadotropin-Releasing Hormone- and Vasoactive Intestinal Polypeptide-like Immunoreactivity Accompanying Reestablishment of Photosensitivity in Male Dark-Eyed Juncos (Junco hyemalis)

In seasonally breeding, photoperiodic birds, the development of photorefractoriness is associated with decreased brain expression of gonadotropin-releasing hormone-like immunoreactivity (GnRH-li ir) and increased expression of vasoactive intestinal polypeptide-like immunoreactivity (VIP-li ir). Dissipation of photorefractoriness and reestablishment of photosensitivity are associated with increased GnRH-li ir brain production, but concurrent changes in VIP-li ir expression have not been investigated. To address this question, we compared the expression of VIP-li ir in the infundibulum (INF) of adult male dark-eyed juncos (Junco hyemalis) that were made photorefractory (PR) by prolonged exposure to long days with that of birds that were not photostimulated (PS), but had regained photosensitivity by exposure to short days for 5 (short-term-PS, ST-PS) or 13 (long-term-PS, LT-PS) consecutive months. Photosensitive males had smaller INF VIP-li ir cell bodies than PR males, but the numbers of INF VIP-li ir cells were independent of photoperiodic condition. Changes in infundibular VIP-li ir were correlated with changes in preoptic area (POA) GnRH-li expression. Specifically, photosensitive males had more and larger POA GnRH-li ir cells and more GnRH-li ir fibers in this region than PR males. Further, LT-PS males had more GnRH-li ir POA fibers and larger testes than ST-PS juncos. Thus, induction of photorefractoriness is associated with increased VIP and decreased GnRH brain expression whereas dissipation of photorefractoriness concurs with decreased VIP and increased GnRH brain expression. These results suggest a physiological role for VIP in the control of changes in GnRH expression as a function of the photosensitive condition.

Expression of tissue inhibitor of metalloproteinase-1 protein and messenger ribonucleic acid by the oviduct of cyclic, early-pregnant, and ovariectomized steroid-treated gilts.

It has been suggested that tissue inhibitor of metalloproteinases (TIMP)-1 has a role in reproductive tissues, regulating tissue remodeling or enhancing embryonic development. Oviductal TIMP-1 mRNA levels and protein expression were examined in gilts during the estrous cycle and early pregnancy and in steroid-treated ovariectomized (OVX) gilts by explant culture, two-dimensional SDS-PAGE and fluorography, dot-blot hybridization, immunoblot analysis, RIA, and immunocytochemical studies. TIMP-1 mRNA levels in the oviduct during the estrous cycle were greater (p < 0.02) on Days 2, 15, and 18 than on other days examined, and analysis of oviductal functional segments indicated an effect of day (p < 0.003), an effect of segment (p < 0.007), and a day x segment effect (p < 0.03). The level of TIMP-1 mRNA was greater (p < 0.003) in the isthmus (I) on Day 2 than in the ampulla (A) or infundibulum (INF) or on other days examined (0 and 12). In steroid-treated OVX gilts, an effect of treatment with estradiol valerate (EV) + progesterone (P4) was shown with increased (p < 0.003) TIMP-1 mRNA levels. De novo synthesis of TIMP-1 protein was found throughout the estrous cycle and early pregnancy in all functional segments, but protein expression was greater in the I and greatest on Day 2. In steroid-treated OVX gilts, TIMP-1 protein synthesis was greatest in the I regardless of treatment, but with increased intensity after EV+P4 treatment. TIMP-1 protein was found in oviductal flushings during the estrous cycle and early pregnancy, and in steroid-treated OVX gilts regardless of day, status, or treatment. Differences in TIMP-1 concentrations in oviductal fluid were found by day (p < 0.001), with breed differences detected between the Meishan and standard Western breeds. TIMP-1 protein was immunolocalized primarily to luminal epithelium of the INF, A, and I on all days of the estrous cycle and early pregnancy and to some cells in the stroma and blood vessel walls. Staining intensity correlated with TIMP-1 protein levels in oviductal flushings. The role of TIMP-1 in the oviduct remains to be established.

Molecular cloning and characterization of an estrogen-dependent porcine oviductal secretory glycoprotein.

A family of estrogen-dependent porcine oviductal secretory glycoproteins (POSPs) that exhibit structural similarities are synthesized and secreted into the oviductal lumen at proestrus, estrus, and metestrus. The objectives of this study were to clone the POSP cDNA, obtain the full-length cDNA and protein sequence, examine tissue specificity and species distribution, characterize its regulation, and establish its identity by comparison to other known protein, RNA, or DNA sequences. A full-length cDNA of 2022 base pairs was obtained with an open reading frame of 1581 nucleotides, coding for a deduced protein of 527 amino acids (57 970 M(r)). The deduced protein contained three potential N-glycosylation sites, a consensus heparin-binding site, and potential O-glycosylation sites. Amino acid analysis of POSP-E3 confirmed the presence of a 21-amino acid signal sequence. Northern blot analysis revealed an oviduct-specific mRNA species of 2.25 kb in the infundibulum (INF), ampulla (A), and isthmus (I). An mRNA of similar size was detected in the oviduct of the sheep, cow, and rabbit, and one of slightly greater size (2.8 kb) in the mouse and hamster oviduct but not in the horse or alligator oviduct. Dot blot analysis indicated that steady-state levels of POSP mRNA were significantly greater (p = 0.0001) in the A than in the INF or I regardless of day of the estrous cycle and were greater on Day 0 (estrus; p = 0.0001) regardless of location. Further, steady-state mRNA levels were significantly increased (p = 0.02) on Days 0 and 1, declining rapidly to Day 2 through Day 15 of the estrous cycle. Steady-state POSP mRNA levels were significantly greater (p < 0.003) in ovariectomized gilts treated with estradiol valerate than those treated with other steroid regimens, vehicle, or no treatment (Control), consistent with estrogen control of mRNA expression. The POSP protein exhibited significant identity to oviductal glycoproteins from the baboon, cow, hamster, human, mouse, and sheep, to several mammalian nonoviductal glycoproteins; and to several chitinases. POSP joins a growing subfamily of the chitinase gene family that lacks chitinase enzymatic activity.

Surgical Anatomy of the Paranasal Sinuses

Good understanding of the antomy of the paranasal sinues is the basis for endoscopic sinus surgery (ESS) . Antomical terminlogy of the paranasal sinuses has not always been clearly defined so far and, in some cases, confusing. The word inf undibulum has been used to indicate different places in the paranasal sinuses. The author tried to clear the difficulties and explain the anatomy of the paranasal sinus in explicit way for practical use in ESS.

Changes in luteinizing hormone-releasing hormone content of discrete hypothalamic areas associated with spontaneous and induced preovulatory luteinizing hormone surges in the domestic hen.

It is widely assumed that luteinizing hormone-releasing hormone (LHRH) neuronal activation is involved in the preovulatory surge of LH in the hen. In addition, this LH surge may be initiated by ovarian progesterone (P4) release. Thus, spontaneous and P4-induced LH surges should be associated with acute changes in LHRH content of discrete hypothalamic areas associated with LHRH cell bodies and/or LHRH axon terminals. Medial preoptic area (mPOA) and infundibulum (INF) LHRH content was measured by radioimmunoassay at intervals before, at, and following peak LH levels of a spontaneous preovulatory surge of LH, as well as when this surge was advanced by P4 administration in laying hens. Nonlaying birds served as additional controls. Levels of serum LH, P4, 17 beta-estradiol and pituitary LH were also measured. Increased (P less than 0.05) LHRH content in mPOA without changes in the INF are associated with peak serum LH levels of the spontaneous LH surge. By contrast, decreased (P less than 0.05) LHRH content in both mPOA and INF is associated with peak serum LH levels when the spontaneous surge was advanced 8 h by P4 administration to laying hens. Medial preoptic area and INF LHRH contents were significantly lower (P less than 0.05) in nonlaying than in laying hens.(ABSTRACT TRUNCATED AT 250 WORDS)

GnRH localization in the equine brain and infundibulum: An immunohistochemical study

Immunohistochemical localization of the decapeptide gonadotropin releasing hormone (GnRH) in neural structures in the pony brain and infundibulum (INF) was conducted at the light-microscopic level. This procedure utilized an antiserum generated against GnRH conjugated to bovine serum albumin. In the rostral INF, GnRH was distributed mainly in the external layer, with greatest concentrations adjacent to the long capillary loops of the hypophyseal portal system. The intermediate portion of the INF contained the hormone throughout the external layer, especially in the dorsolateral regions just ventral and medial to the tuberoinfundibular sulcus (TIS) with lesser amounts dorsal to the TIS. Caudally, GnRH was very concentrated along the medial border of the TIS, and in small amounts within the medial portion of the INF just rostral to the mammillary bodies. Throughout the INF, reaction product was noted in the internal layer, although the concentration was less than that observed in the external layer. The hormone was localized in axons of the brain from the medial and lateral septal nuclei through the mammillary region. GnRH positive perikarya were localized in the lamina terminalis, infundibular nucleus and the caudal periventricular nucleus. Preabsorption of the specific antiserum with synthetic GnRH abolished staining in both axons and perikarya, whereas preabsorption with other hypothalamic peptides did not affect staining intensity.

Immunohistochemical localization of gonadotropin-releasing hormone (GnRH) in the brain and infundibulum of the sheep.

The distribution of gonadotropin-releasing hormone (GnRH) was studied in the brain and infundibulum (INF) or median eminence of sheep utilizing a peroxidase-antiperoxidase immunohistochemical method. This procedure utilized a specific antiserum generated against GnRH conjugated to bovine serum albumin. In the rostral INF, the greatest concentration of GnRH positive axons was found in the medial region, mostly in the external layer dorsal to the hypophysial portal plexus. In the intermediate portion of the INF, the hormone was mainly observed in the external layer at the more dorsolateral areas ventral to the tuberoinfundibular sulcus. GnRH was generally located medially in the caudal portion of the INF and dorsomedially in the rostral infundibular stalk. Substantial amounts of reaction product were also noted in the internal layer throughout the entire rostrocaudal extent of the INF. The hormone was localized in axons throughout the brain from the septal and medial preoptic areas to the mammillary bodies. GnRH-positive perikarya were scattered in various regions of the infundibular (arcuate) and for the first time in the ventromedial nuclei of sheep hypothalamus. Preabsorption of the specific antiserum with synthetic GnRH abolished staining in both axons and perikarya, whereas preabsorption with thyrotropin-releasing hormone, oxytocin, arginine-vasopressin, and adrenocorticotrophic hormone did not affect staining intensity.

The armadillo infundibulum: Correlative histochemistry, scanning and transmission electron microscopy of the ventricular surface

The ependymal and supraependymal cells of the armadillo infundibulum (INF) were investigated by correlative histochemistry, scanning and transmission electron microscopy. Eighteen armadillos (8 adult females, 6 adult males, 2 immature females and 2 immature males) were examined. The following supraependymal elements were observed: (a) individual pleiomorphic cells made up of neurons, macrophages, and astrocytic-glial cells; (b) numerous spherical blebs of various sizes occurring singly or in clusters; (c) axons, traversing the surface alone or in association with macrophages and other SEC; (d) multicellular clusters containing SEC, macrophages, axons and other cell types. There were neurosecretory axons or blebs on and below the ependymal cell layer and a unique arrangement of multipolar cells and their processes, traversing the INF floor for several millimeters. The presence of neurosecretory axons at the INF ventricular surface, spherical blebs and SEC in contact with one another via long filaments or vast networks of smaller axons on the surface and numerous macrophages in close apposition to possible metabolic and transport sites give evidence of organized activity in a regulatory system.