Bicameral Chamber Research Articles

Sort[Ition]Ing Out Local Government Financial Sustainability

Many local governments across the globe are facing financial sustainability challenges. Notably these challenges have emerged under extant democratic political institutions where the voice of the wider citizenry is often muted, and only heard at infrequent intervals and then in the context of assessing potential representatives according to a bundle of issues. Fiscal institutions such as balanced budget legislation and debt brakes may mitigate some of the financial sustainability problems faced by local government, but are often less than entirely effective owing to the acts of clever politicians who circumvent the spirit, if not the letter, of constraints. We propose a concurrent change to political institutions – specifically the addition of a bi-cameral sortition chamber – which we argue will inter alia enhance the efficacy of fiscal institutions implemented to arrest waning local government financial sustainability by introducing greater accountability, closer monitoring, and a more expedient pathway for censure and enforcement.

PENGUATAN KEDUDUKAN DAN KEWENANGAN KONSTITUSIONAL DPD RI DALAM PERSPEKTIF UUD NEGARA RI TAHUN 1945

The dynamics in the system and structure of the Indonesian constitution began in the reform era so quickly developed. All can run properly and correctly because it was initiated by reforming the constitution through an amendment or constitutional amendment mechanism (the 1945 Constitution) in four stages of change (1999 - 2002). One of the essence of the amendment, gave birth to the Regional Representative Council (DPD RI) as a state institution with its constitutionality can be found explicitly in Chapter VIIA Article 22 C Paragraph 1 - Paragraph 4 and Article 22 D Paragraph 1 - Paragraph 4. And UUNO. 17 of 2014 Jo UUNo.2 of 2018 concerning the MPR, DPR, DPD, DPRD. As a new post-amendment state institution, the DPD is designed as a strong bicameral second chamber of our parliament which was originally only unicameral, namely the DPR RI as a state institution and a representative institution of the people. But one of the characteristics of bicameral is if both parliamentary chambers carry out the legislative function as they should. However, if examined carefully until now based on the substitution of article 22 C and Article 22D of the 1945 Constitution of the Republic of Indonesia in 1945 the authority and authority of the DPD is still very limited. So that as an organic law does not give much space for the implementation of authority to the DPD in carrying out its main duties and functions, especially the legislative function like the DPR. For this reason, in order to strengthen and empower the future, the DPD's consistency and authority need to get priority place in the context of the subsequent amendments to the 1945 Constitution of the Republic of Indonesia as the Holder of strategic and fundamental national political decision authority. Everything is inseparable from the problems in the DPD now is a matter of the authority granted by the constitution to him, especially in the context of the legislative function to make laws. Its existence is expected to bridge the relationship between the center and the regions, in a two-chamber parliamentary frame which has strong bicameralism authority.

Hepatocytes cocultured with Sertoli cells in bioreactor favors Sertoli barrier tightness in rat.

The lack of a reliable in vitro system to assess reprotoxicity is an emerging problem in the context of European law for Registration, Evaluation, Authorization and Restriction of Chemicals (REACH, 2007), as it requires a reduction in animal utilization for testing. Furthermore, in vitro reprotoxicological tests would be more relevant and greatly improved by integrating both hepatic metabolism and the blood-testis barrier. Here, we took advantage of an integrated insert in a dynamic microfluidic platform (IIDMP) to co-cultivate hepatocytes in biochip and Sertoli cells in the bicameral chamber. This microfluidic tool has been previously demonstrated to be helpful in cell function and/or quality improvement. We demonstrate that permeability of the Sertoli barrier is reduced by dynamic coculture in our system. Exometabolomics analysis reveals that interactions between hepatocytes and Sertoli cells may have been mediated by the polyamines increase and/or mid-chain fatty acid decrease in the circulating medium. These metabolic changes may be involved in permeability reduction by contributing to modifying junction protein quantity and localization. The present study gives an example of IIDMP as an in vitro partitioning/transport model for cell culture and toxicological testing. Further, based on both our previous results using an intestinal-hepatic cell coculture and the present study, IIDMP seems to be well-suited for (i) assessing the dose-response effect of chemicals within the rodent or human male reproductive tract, and (ii) improving the quality of reprotoxicological assays by including hepatic metabolism. Copyright © 2016 John Wiley & Sons, Ltd.

Abstract 4225: Expression of NANOG in a prostate cancer cell line increases CD24 expression and enhances cell invasion

Abstract The transcription factor NANOG is critical for the maintenance of embryonic stem cell properties including self-renewal and pluripotency. NANOG performs these functions by regulating the expression of genes required for the preservation of the stem cell phenotype. Introduction of NANOG and other embryonic stem cell genes has successfully established disease-specific induced pluripotent stem cells in several types of human cancers. Although the expression of NANOG has been documented in cancer cells, the function of NANOG in cancer has not been extensively investigated. We hypothesized that NANOG plays a role in prostate cancer cell biology based on our observation of NANOG protein expression in prostate cancer cell lines. To test this hypothesis, we transduced the PC3 prostate cancer cell line with a lentivirus capable of directing the expression of NANOG. A stable cell line containing the NANOG expression cassette was established by selection with puromycin, and expression of NANOG protein was verified by Western blot analysis. Analysis of stem cell surface markers by flow cytometry in the PC3-NANOG cells and PC3 cells transduced with empty virus revealed an increase in the percentage of CD24 positive cells in the PC3-NANOG sample as compared with the control. In addition, the density of CD24 per cell appeared to increase. This increase in CD24 expression was confirmed by Western blot analysis. In multiple cancers expression of CD24, a mucin-like adhesion protein, correlates with invasion and metastatic potential. Therefore, we conducted an invasion assay to assess the ability of PC3-NANOG cells to invade through a matrix assaying invasion by migration of cells from one chamber of a bicameral chamber through a porous membrane. The results showed that PC3-NANOG cells exhibited a 30-40% increase in invasion as compared to the control cells. (p<0.001). These results suggest that expression of NANOG in a prostate cancer cell line contributes to increased invasive capacity, possibly through enhanced expression of CD24. Therefore, NANOG could be a potential mediator of prostate cancer cell invasion and maneuvers to decrease NANOG expression could be a new therapeutic target for treatment of prostate cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4225.

An engineered 3D blood-testis barrier model for the assessment of reproductive toxicity potential

We have developed an in vitro model that replicates the composition, organization, and barrier and spermatogenesis functions of the in vivo rat blood-testis barrier. This engineered blood-testis barrier (eBTB) is based on a three-dimensional (3-D) culture in a bicameral chamber of testicular cells isolated from 18-day-old rats. Peritubular cells were cultured on the bottom of the insert. On the top of the insert, a mixture of Sertoli and germ cells were coated within an artificial extracellular matrix, thereby mimicking the basement membrane. The matrix composition was defined to obtain a cord-like organization. This structure was revealed depending on morphogenetic gradients, and was made of polarized Sertoli cells and germ cells in the center of the structure. The in vivo functionality of the BTB was characterized by tight junctions between Sertoli cells. Claudin-11 protein immunodetection suggests that these junctions were also implicated in vitro in the cord-like structure, suggesting the presence of a physical compartment with apical and basal spaces. Measurement of the trans-epithelial electrical resistance characterized the relationship between the Sertoli cells, peritubular cells, and matrix/cells that influenced the tightness of their junctions during the course of the culture. In vitro germ cell differentiation was confirmed with the detection of haploid cells. The development of the eBTB under optimum conditions addresses the involvement of new models, testing the barrier and spermatogenesis functions that are sensitive to chemical compounds from the environment. In this way, the eBTB could be used as an alternative method to animal reprotoxicity studies, and would be of high interest in the scope of regulatory requests for chemical risk assessment.

Amiodarone Inhibits Thyroidal Iodide Transportin Vitroby a Cyclic Adenosine 5′-Monophosphate- and Iodine-Independent Mechanism

Thyroid side effects are common in patients treated for cardiac arrhythmias with amiodarone (AM). A major disturbance is inhibited thyroidal radioiodine uptake in AM-induced thyrotoxicosis, which makes 131I therapy ineffective. On the other hand, failure to escape from the Wolff-Chaikoff effect by down-regulation of the sodium/iodide symporter (NIS) is proposed to explain AM-induced hypothyroidism. However, previously no experimental studies on the possible mechanisms have been conducted. We therefore investigated the early effects of AM on thyroidal iodide transport using bicameral chamber cultures of primary pig thyrocytes that reproduce the three tissue compartments (epithelium, lumen, and extrafollicular space) of the gland. AM dose-dependently (1-50 microm) inhibited the TSH-stimulated transepithelial (basal to apical) transport of 125I- by up to 90%. The inhibitory effect was noticed already after 8 h and was further pronounced after 1-4 d, depending on the AM concentration. The intracellularly accumulated 125I- was reduced by perchlorate but not AM, and quantitative real-time RT-PCR revealed no change in the NIS expression in AM-treated cells. Blocking of cAMP degradation with 3-isobutyl-1-methylxanthine or withdrawal of AM reversed AM-induced changes in electrolyte transport but were unable to recover the suppressed 125I- transport. The iodine-free AM analog dronedarone also inhibited 125I- transport to the same extent as AM. The findings indicate that AM blocks thyroidal iodide uptake by reducing the iodide permeability of the apical plasma membrane of the thyroid epithelial cells. The effect is iodine independent and long-lasting and does not involve impaired function of NIS or the TSH receptor/cAMP signaling pathway.

Empirical Determinants of Bicameral Sequence in State Legislatures

In a previous article (Rogers 1998), I showed that the bicameral chamber that originates enacted legislation tends to realize policy outcomes closer to the preference of its median legislator than does the chamber that votes second on legislation. All things being equal, this �first-mover advantage� implies that each chamber could be expected to originate roughly half of all enacted legislation. But all other things are not equal in U.S. state bicameral legislatures. Drawing on an expanded dataset, I innovate and test a number of additional hypotheses related to bicameral voting sequence. My results account for the effects of constitutional, institutional, and electoral variables on bicameral sequence.

An in vitro model based on cell monolayers grown on the underside of large- pore filters in bicameral chambers for studying thyrocyte-lymphocyte interactions.

In the processes underlying thyroid autoimmunity, thyrocytes probably act as antigen-presenting cells exposing T-cell epitopes to intrathyroid lymphocytes. To study the interactions between lymphocytes and thyrocytes, which are arranged in a tight, polarized monolayer, we developed a new in vitro model based on human thyrocytes grown on the underside of a filter placed in a bicameral chamber. Thyrocytes from Graves' disease glands were plated onto the upper face of a 8-mum-pore polyethylene terephthalate culture insert filter placed in the inverted position and grown for 24 h before the insert was returned to the normal position for a week in the cell culture plate wells. Thyrocytes grown in the presence of thyroid stimulating hormone, forming a homogeneous monolayer on the underside of the filter, reached confluence after 8 days in vitro. The cells developed a transepithelial electrical resistance >1,000 Omega.cm(2), and the ZO-1 tight junction protein showed a junctional pattern of distribution. Thyrocytes showed a polarized pattern of thyroperoxidase and thyroid stimulating hormone receptor expression in the apical and basolateral positions, respectively. They were also found to aberrantly express DR class II human leukocyte antigen and an Fc immunoglobulin receptor (FcgammaRIIB2) in the basolateral and apical positions, respectively. Autologous intrathyroidal T lymphocytes cocultured for 24 h across the filter with the thyrocyte monolayer proliferated and remained in the upper chamber without any leakage occurring through the epithelial barrier, which makes this model particularly suitable for studying the cell-cell interactions involved in antigen processing.

Interferon-gamma down-regulates claudin-1 and impairs the epithelial barrier function in primary cultured human thyrocytes.

Proinflammatory cytokines are known to affect the follicular epithelium in autoimmune thyroid disease. Here we investigated the effect of interferon-gamma (IFN-gamma) on the barrier function of primary cultured human thyrocytes. Graves' thyroid follicle segments were cultured as a tight and polarised monolayer on the filter of a bicameral chamber, thereby allowing the in vivo epithelial characteristics to be maintained. Transepithelial electrical resistance was measured with a Millicell ERS ohmmeter. The tight junction proteins claudin-1 and occludin were analysed by immunofluorescence and Western blotting. Cell morphology was studied by transmission electron microscopy. Thyrotrophin (TSH; 1 mU/ml) promoted the development of a tight epithelium monitored as a persistent increase in the transepithelial resistance to about 800 omega x cm2. IFN-gamma (100 U/ml), on the other hand, decreased the resistance to 60-150 omega x cm2 after 48 h. In IFN-gamma-treated cells the expression of claudin-1, but not that of occludin, was decreased along with a diminished intracellular and cell surface immunostaining. In addition, claudin-1 was disrupted at cell-cell contacts. IFN-gamma also caused profound cell shape changes and a multilayered cellular organisation, without ultrastructural or biochemical (caspase-3 activity) signs of cytotoxicity. TSH was unable to counteract the effects of IFN-gamma. IFN-gamma destroys the barrier function of filter-cultured human thyroid epithelial cells. The loss of barrier involves down-regulation and an altered distribution of claudin-1. This novel effect of IFN-gamma on target cells in thyroid autoimmunity might be of pathophysiological relevance to the exposure of hidden autoantigens.

CO-CULTURE OF HUMAN MONOCYTES AND THYROCYTES IN BICAMERAL CHAMBER: MONOCYTE-DERIVED IL-1α IMPAIRS THE THYROID EPITHELIAL BARRIER

Pro-inflammatory cytokines are important mediators in tissue responses to a wide range of endogenous (e.g. autoantigens) and exogenous (e.g. infections, wounds, biomaterials) stimuli. The complex interactions taking place between different cell types in such processes are difficult to examine in vivo. Here we studied the effect of human monocytes on thyroid epithelial cells co-cultured in bicameral chambers. Freshly isolated monocytes (1×106/ml) added to the basal compartment reduced the transepithelial resistance (from 300–600 to <100Ω·cm2) and caused a disruption of the tight junctions in apically grown thyrocyte monolayers after co-culture for 24h. The barrier function was further attenuated by monocytes exposed to lipopolysaccharide (10μg/ml) or polystyrene microspheres (size: 3μm; 1×107/ml). Loss of transepithelial resistance was accompanied by release of interleukin 1α (maximally 550pg/ml) from the monocytes. Conversely, the resistance remained high when co-cultures were simultaneously incubated with neutralizing anti-human interleukin 1α antibodies. The results show that the integrity of cultured thyroid epithelium is impaired by monocytes without requirement of direct cell-to-cell contact. This action, mediated by interleukin-1α, suggests a mechanism by which hidden (lumenal) autoantigens might be exposed to interstitial antigen-presenting cells in autoimmune thyroid disease. In perspective, the model provides a tool in which humoral and cell-cell dependent processes generated by bioactive agents and particulate materials, for instance, during the healing and repair of tissue around biomaterials and hybrid implants, can be selectively examined.

Bicameral Sequence: Theory and State Legislative Evidence

Theory: Voting sequence is a strategic variable between bicameral chambers. Decisions by chambers to acquire costly information affect the payoffs chambers receive from sequencing choices. Thus, it is also a strategic variable between bicameral chambers. Hypotheses: (1) Because of incentives to take advantage of one chamber's informational expertise when chambers share relatively homogeneous policy preferences, house chambers in legislatures dominated by a single party will initiate adopted legislation in greater proportion relative to legislatures that are not dominated by a single party. (2) A cost advantage in acquiring information grows with an increasing disparity in the number of legislators between bicameral chambers. Lower information acquisition costs in the larger bicameral chamber account for a persistent first-mover advantage for that chamber. Methods: Hypotheses are derived from a game theoretic model in which informational endowments are endogenously chosen by bicameral chambers and in which voting sequence is endogenously determined. Implications of the model are tested with an original data set developed from the session laws of thirty-three state legislatures. Results: Under specified conditions, bicameral chambers sequence themselves to take advantage of one chamber's informational expertise. Under other conditions, bicameral chambers will not take advantage of a chamber's informational expertise. The main theoretical results conclude: (1) that one-party legislatures take greater advantage of informational expertise relative to divided-party legislatures; (2) that senators have an incentive to specialize in more risky policy environments relative to house members; and, (3) that there is an informational basis for house chambers to initiate more adopted legislation than senate chambers. The empirical results are consistent with hypothesis 1. The results are consistent with hypothesis 2, although an alternative (noncontradictory) theory might also account for the result.

Morphology and function of rooster efferent ductule epithelial cells in culture

Regulation of the excurrent ducts of the testis is not well understood, particularly in avian species. To investigate the role of steroid hormones in the male reproductive tract, we developed a primary cell culture of epithelia isolated from rooster ductuli efferentes (efferent ductules). Efferent ductules of the avian testis comprise 77% of the epididymal region and form a mass of tubules containing a heavily folded epithelium enmeshed in connective tissue. The epididymal region was separated by microdissection and small epithelial plaques isolated by serial digestion with collagenase, elastase and repeated pipetting. Isolated cell plaques were cultured in a bicameral chamber on Millicell-CM inserts coated with two layers of basement membrane matrix, consisting primarily of laminin and Types I and IV collagen. Active ciliary beat was observed before plating and this activity was maintained for 14 days in culture. Cell plaques attached within 24 h and outgrowths formed a confluent monolayer by 5–6 days. The epithelial nature of cultured cells was demonstrated by immunocytochemical staining for cytokeratin. Light and electron microscopy confirmed that morphology and polarity of the original epithelial cells were maintained in culture. Cultured efferent ductal epithelium was cuboidal in shape and maintained many of the cytoplasmic organelles typical of these cells in vivo. The uptake of cationic ferritin indicated the endocytotic activity of these cultured cells was maintained. Estrogen receptor mRNA expression was maintained in cultured cells. These data demonstrate avian efferent ductal epithelium can be isolated and grown in defined culture medium for the purpose of determining the role of hormones and other factors in regulating the function of the epididymal region in the bird.

Primary culture of human thyrocytes in Transwell bicameral chamber: thyrotropin promotes polarization and epithelial barrier function.

Epithelial properties of thyrocytes are difficult to maintain in conventional cell culture systems. We used bicameral chambers (Transwell) in attempts to establish a functional epithelium of thyrocytes of human origin. Thyroid follicle segments were isolated by collagenase digestion of paradenomatous tissue obtained at surgery for follicular adenoma and of tissue from glands with Graves' disease. After careful separation from connective tissue and single cells by centrifugation, the follicles were plated at high density on the collagen-coated filter of the chambers and cultured in Eagle's essential medium (EMEM) containing 10% fetal calf serum (FCS) or Coon's modified Hams medium enriched with five or six factors (5H, 6H); the latter media contained 5% FCS without (5H) or with (6H) thyrotropin (TSH). The follicles were converted into a confluent cell layer, which had similar DNA content irrespective of type of medium, after 4-6 days. Cells grown in EMEM or 5H established a transepithelial electrical resistance (R) of 200-500 omega.cm2 and was impermeable to [3H]inulin, indicating the formation of epithelial junctions. Addition of 6H to confluent cells initially cultured in EMEM or 5H caused a further increase of R, maximally to 1500 omega.cm2, along with a rise of the transepithelial potential difference; 6H promoted the monolayer formation of cells, increased the number of apical microvilli and reinforced the junctional distribution of actin, cadherin and ZO-1; 6H also enhanced the polarized secretion of [3H]leucine-labeled thyroglobulin into the apical medium. Cells from Graves' thyroid tissue established an epithelium on the filter with similar characteristics to that of normal thyrocytes; some platings contained in addition large numbers of HLA-DR positive cells with a dendritic shape. HLA-DR expression was generally absent in EMEM-or 5H-grown thyrocytes, but appeared in limited areas of the cell layer after 6H and was expressed by all epithelial cells after interferon-gamma stimulation for 48 h. We conclude that human thyrocytes form a tight and polarized epithelium when cultured on permeable filters. The polarized structure and function of the cells are positively regulated by TSH. The culture system may be useful in studies addressing the role of the epithelial phenotype (cell polarity and tight barrier) in normal thyroid function as well as in pathological processes in the thyroid, such as autoimmunity, cell transformation and tumor progression.

Effect of chloroquine on the formation of tight junctions in cultured immature rat Sertoli cells.

Adjoining immature Sertoli cells in the seminiferous epithelium form a tight junctional complex leading to the development of the blood-testis barrier. Protease and antiprotease activities have been implicated in the process of formation of tight junctions. Here, we report the effect of chloroquine, an antimalarial drug with antiprotease activity, on the development of intercellular tight junctions in cultured immature rat Sertoli cells. For positive control, the classical lysosomotropic agent ammonium chloride was used. Sertoli cells were seeded in serum-free defined medium at a density of 3 x 10(6) cells/0.64-cm2 well on Matrigel-covered Millicell-HA filters. Chloroquine at concentrations ranging from 25 to 100 microM was added to the outer chamber of the bicameral system on either day 1 or 7 of the culture. The formation of the tight junction was monitored by the measurement of the transepithelial resistance (TER) at 24-hour intervals using an impedance meter. TER in untreated controls was 50 ohms/cm2 on day 1; it increased progressively to 80 ohms/cm2 by day 7 and plateaued until day 12. The cells treated from day 1 with chloroquine also showed a dose-dependent progressive increase in TER until day 9, reaching 225 ohms/cm2 in cells treated with the 100 microM concentration. In comparison to controls, the increase in TER was significantly higher. In cells treated with chloroquine starting from day 7 of culture onwards, there was no observable difference in TER from the untreated control. These observations demonstrate that chloroquine and ammonium chloride increase the TER of immature Sertoli cells in the bicameral chamber.

Proliferation of newt spermatogonia by mammalian FSH via Sertoli cells in vitro

Our previous studies showed that mammalian follicle-stimulating hormone (FSH) stimulated the proliferation and differentiation of secondary spermatogonia into primary spermatocytes in organ culture of testes fragments from Cynops pyrrhogaster. To elucidate how FSH stimulates spermatogonial proliferation, we studied the interaction of spermatogonia with somatic cells in the presence or absence of FSH in cultures of aggregated cells derived from fractionated cell populations. When spermatogonia or those with somatic cells were cultured, they formed aggregates with themselves or with somatic cells, respectively. Most of the somatic cells in the aggregates were Sertoli cells, judged by the lipid droplets in their cytoplasm. [3H]thymidine incorporation into aggregates and autoradiography demonstrated spermatogonial proliferation that was enhanced in the presence of FSH and somatic cells (most probably Sertoli cells), but not in the absence of FSH or in the presence of luteinizing hormone (LH). To examine whether direct contact between spermatogonia and Sertoli cells is indispensable for the stimulation of spermatogonial proliferation by Sertoli cells, the two cell types were separated by a 0.4 micron pore filter in two compartments of a bicameral chamber. In this case, Sertoli cells did not stimulate spermatogonial proliferation in the presence of FSH, indicating that direct contact between spermatogonia and Sertoli cells is indispensable for the stimulation of spermatogonial proliferation by Sertoli cells. Finally, Sertoli cells isolated from the testes from the primary spermatocyte stage did not stimulate spermatogonial proliferation in the presence of FSH. This result indicated that the function of Sertoli cells with respect to their stimulation of proliferation was stage-specific.

Growth factors (EGF, IGF-I) modulate the morphological differentiation of adult marmoset (Callithrix jacchus) Sertoli cells in vitro.

The effects of epidermal growth factor (EGF) and insulin-like growth factor I (IGF-I) on mature marmoset (Callithrix jacchus) Sertoli cells in vitro were investigated using light and electron microscopic and histochemical means. The morphological data were substantiated by morphometric analysis at the electron microscopic level. In a bicameral chamber system, cultured Sertoli cells displayed a high degree of ultrastructural differentiation and exhibited a polarized appearance. Basally located tight junctions joined adjacent cells. Germ cells of early stages of development were regularly seen. Under the influence of IGF-I, cells developed extensive cell-cell contacts. The surface density of smooth endoplasmic reticulum was increased. In contrast, the volume density of lipid inclusions was decreased. The morphological integrity of enclosed germ cells was maintained for a longer period. With EGF, cells were arranged in loose aggregates. Intercellular spaces were widened. The volume density of lipid inclusions was increased. Germ cells exhibited profound signs of degeneration early in culture, paralleled by increased development of phagolysosomes and high acid-beta-galactosidase activity. Under the influence of either growth factor, mitochondria displayed a shift from the crista to the tubulo-vesicular type. Mitochondrial dimensions and the volume density of mitochondrial compartment were increased. In comparison with control cultures all documented changes were statistically significant. Our findings indicate that marmoset Sertoli cells are target cells for EGF and IGF-I. Moreover, the dynamics of intercellular contacts, germ cell survival, and morphological indices of lipid and/or steroid metabolism seem to be differentially modulated.

Proliferative and morphogenic changes induced by the coculture of rat uterine and peritoneal cells: a cell culture model for endometriosis

To evaluate the proliferative and morphogenic effects induced by the coculture of uterine and peritoneal cells to establish a cell culture model for endometriosis. Uterine epithelial and stromal cells and peritoneal mesothelial and subserosal cells were cocultured with homologous cell types, heterologous cell types, or as isolated populations using a bicameral chamber design. Department of Obstetrics and Gynecology at the University of Missouri, Columbia, Missouri. Cells isolated and purified from five mature female Sprague Dawley rats of normal reproductive status were used to establish cell cultures. Cell proliferation (deoxyribonucleic acid synthesis) was measured by the incorporation of 3H-thymidine, and cell morphology was assessed using inverted phase-contrast microscopy. Peritoneal mesothelial cells augmented proliferation and induced cellular aggregation of uterine stromal cell monolayers. Peritoneal subserosal cells amplified proliferation and induced an irregular, compacted morphology in uterine epithelial cells. The proliferation and morphology of the two peritoneal cell types was not altered by uterine cell coculture. The coculture of uterine and peritoneal cells in bicameral chambers provides a tool to study the paracrine interactions of cells that comprise the endometriotic lesion. The altered proliferation and morphology of the uterine cells may be related to the histologic and biochemical asynchrony observed between uterine endometrium and ectopic endometriotic tissue in vivo and offers insight into possible mechanisms of the histogenesis of endometriosis.

Structural and functional aspects of the thyroid follicular epithelium

The thyroid epithelium is morphologically and functionally polarized, with an apical surface facing the follicular lumen containing colloid and a basolateral surface facing the interstitium. Iodination and thyroid hormone synthesis occur in the colloid at the apical plasma membrane. The introduction by Mauchamp et al. of primary cultures of porcine thyroid cells grown as a polarized, confluent monolayer on a filter in a bicameral chamber system has now made it possible to study in more detail the barrier function and vectorial ion transport in the thyroid epithelium. The follicular cells form a very tight monolayer (transepithelial resistance > 6000 ohm cm 2) and establish a transepithelial potential difference (apical medium negative) of about 20 mV. These parameters are rapidly influenced by TSH, mainly by an action on apical sodium channels, and by EGF. The integrity of the barrier is, as in other epithelia, dependent on extracellular calcium. A calcium-dependent cell adhesion molecule, uvomorulin, is expressed at the lateral plasma membrane surface. EGF induces cell proliferation as well as migration of some of the epithelial cells to a position below the monolayer, which however maintains its polarity and barrier function. In contrast, during TPA-induced proliferation the barrier function is disrupted. Iodide is vectorially transported in basoapical direction while the epithelial layer is virtually impermeable for iodide transfer in the opposite direction. Iodide is concentrated in the cell by the basolateral “iodide-pump” and its efflux across the apical plasma membrane is rapidly and selectively increased by TSH via cAMP. EGF inhibits vectorial basoapical iodide transport mainly by reducing the iodide permeability of the apical plasma membrane. Together, these recent observations indicate that the ion content of the follicular lumen is strictly controlled by the thyroid epithelium.

Opposite vectorial secretion of insulin-like growth factor I and its binding proteins by pig Sertoli cells cultured in the bicameral chamber system.

A two-chamber system has been employed to investigate the vectorial secretion of insulin-like growth factor I (IGF-I) and its binding proteins (IGF-BPs) by pig Sertoli cells. The kinetics of transport of [3H]insulin as well as the transepithelial electrical resistance of filters coated with reconstituted basement membrane, in the absence of presence of Sertoli cells, indicated the formation of a functional barrier by Sertoli cells. The rates of diffusion of [125I]IGF-I or [125I]human CG were slower from the apical (AC) to the basal (BC) compartment than in the opposite direction. However, the IGF-I content and concentration in the BC was twice that seen in the AC. FSH increased the secretion of IGF-I in the BC, and therefore increased the BC/AC ratio. In contrast, most of the IGF-BPs, with apparent molecular sizes of 39-43, 34, 29 and 24 kDa, were secreted in the AC. FSH increased the secretion of IGF-BP 39-43 kDa (BP3). This is the first report of opposite vectorial secretion of IGF-I and its binding protein by any cell type.

Opposite vectorial secretion of insulin-like growth factor I and its binding proteins by pig Sertoli cells cultured in the bicameral chamber system

Opposite vectorial secretion of insulin-like growth factor I and its binding proteins by pig Sertoli cells cultured in the bicameral chamber system