[A case of 63,X/64,XX mosaicism in a subfertile pony mare]. / Ein Fall von 63,X/64,XX Mosaizismus bei einer subfertilen Ponystute.

INTRODUCTION: The present case report describes a 6-year old subfertile pony mare, which became pregnant after the eleventh artificial insemination. The examination of the ovaries and the uterus did not reveal any abnormal clinical findings and the mare showed a regular oestrous cycle. Based on cytogenetic and molecular genetic analyses it became possible to elucidate the observed subfertility. The mosaic karyotype of the mare consisted of 63,X (20%) and 64,XX (80%) cells. A PCR analysis failed to amplify sequences from the equine SRY gene. The observed classic 63,X/64,XX mosaicism is a plausible explanation for the subfertility of the mare.

Cell volume regulated transporters of compatible osmolytes.

Virtually all cells respond to hypertonicity by accumulating certain small organic solutes (compatible osmolytes) that, in contrast to intracellular ions, do not perturb macromolecular function. Several important compatible osmolytes are accumulated by coupled transport. Transcription of genes encoding these cotransporters is increased by hypertonicity and a tonicity-responsive enhancer element has been identified. When cells return to an iso-osmotic environment, osmolytes are rapidly lost through a pathway that current evidence indicates may be a volume-sensitive chloride channel.

Microarray analysis of equine endometrium at days 8 and 12 of pregnancy.

Establishment and maintenance of pregnancy in equids is only partially understood. To provide new insights into early events of this process, we performed a systematic analysis of transcriptome changes in the endometrium at Days 8 and 12 of pregnancy. Endometrial biopsy samples from pregnant and nonpregnant stages were taken from the same mares. Composition of the collected biopsy samples was analyzed using quantitative stereological techniques to determine proportions of surface and glandular epithelium and blood vessels. Microarray analysis did not reveal detectable changes in gene expression at Day 8, whereas at Day 12 of pregnancy 374 differentially expressed genes were identified, 332 with higher and 42 with lower transcript levels in pregnant endometrium. Expression of selected genes was validated by quantitative real-time RT-PCR. Gene set enrichment analysis, functional annotation clustering, and cocitation analysis were performed to characterize the genes differentially expressed in Day 12 pregnant endometrium. Many known estrogen-induced genes and genes involved in regulation of estrogen signaling were found, but also genes known to be regulated by progesterone and prostaglandin E2. Additionally, differential expression of a number of genes related to angiogenesis and vascular remodeling suggests an important role of this process. Furthermore, genes that probably have conserved functions across species, such as CRYAB, ERRFI1, FGF9, IGFBP2, NR2F2, STC1, and TNFSF10, were identified. This study revealed the potential target genes and pathways of conceptus-derived estrogens, progesterone, and prostaglandin E2 in the equine endometrium probably involved in the early events of establishment and maintenance of pregnancy in the mare.

Monoclonal antibodies as probes of epithelial membrane polarization.

Monoclonal antibodies directed against antigens in the apical plasma membrane of the toad kidney epithelial cell line A6 were produced to probe the phenomena that underlie the genesis and maintenance of epithelial polarity. Two of these antibodies, 17D7 and 18C3, were selected for detailed study here. 17D7 is directed against a 23-kD peptide found on both the apical and basolateral surfaces of the A6 epithelium whereas 18C3 recognizes a lipid localized to the apical membrane only. This novel observation of an apically localized epithelial lipid species indicates the existence of a specific sorting and insertion process for this, and perhaps other, epithelial plasma membrane lipids. The antibody-antigen complexes formed by both these monoclonal antibodies are rapidly internalized by the A6 cells, but only the 18C3-antigen complex is recycled to the plasma membrane. In contrast to the apical localization of the free antigen, however, the 18C3-antigen complex is recycled to both the apical and basolateral surface of the epithelium, which indicates that monoclonal antibody binding interferes in some way with the normal sorting process for this apical lipid antigen.

Diseases and medical disabilities of enslaved Barbadians, from the seventeenth century to around 1838 part II.

The disease environment, health problems and causes of mortality of enslaved Barbadians are described. Data are derived mainly from documentary sources; also included are bio-archaeological data from analyses of skeletons recovered from Newton Plantation cemetery. Major topics include infectious diseases transmitted from person to person, as well as those contracted through water soil, and other environmental contaminations, and diseases transmitted by insects, parasites and other animals; nutritional diseases, including protein energy malnutrition, vitamin deficiencies, anaemia, and geophagy or "dirt eating"; dental pathologies, lead poisoning, alcoholism, traumas, and other disorders, including psychogenic death or illness caused by beliefs in witchcraft or sorcery.

Diseases and medical disabilities of enslaved Barbadians from the seventeenth century to around 1838. Part I.

The disease environment, health problems and causes of mortality of enslaved Barbadians are described. Data are derived mainly from documentary sources; also included are bio-archaeological data from analyses of skeletons recovered from Newton Plantation cemetery. Major topics include infectious diseases transmitted from person to person, as well as those contracted through water soil, and other environmental contaminations, and diseases transmitted by insects, parasites, and other animals; nutritional diseases, including protein energy malnutrition, vitamin deficiencies, anaemia, and geophagy or "dirt eating"; dental pathologies; and lead poisoning, alcoholism, traumas, and other disorders, including psychogenic death or illness caused by beliefs in witchcraft or sorcery.

Influence of cycle stage, age and endometrial biopsy score on oxytocin receptor distribution and gene expression in the cervix and uterus of non-pregnant mares.

Persistent breeding-induced endometritis (PBIE) or delayed uterine clearance (DUC) are major causes of mare subfertility. Oxytocin and its receptor are thought to play significant roles in the pathogenesis of DUC but the specific roles of oxytocin receptor (OR) distribution and gene expression remain undefined. In this study both OR distribution and gene expression in the endometrium, myometrium and cervix during both luteal and non-luteal phases in non-pregnant mares (n = 27) of differing age (young: 2-9 years, n = 17; old: > 10 years, n = 10) and endometrial biopsy score were described using immunohistochemistry (IHC) and quantitative reverse-transcription polymerase chain reaction (RT-qPCR), respectively. Immunohistochemistry showed a similar pattern of OR distribution in uterus and cervix, with the exception of the glandular epithelium, absent in the cervix. Uterine ORs were localized in endometrial luminal and glandular epithelia, transmural vascular endothelium, sub-epithelial and peri-glandular stromal cells and myometrial smooth muscle cells. The OR labeling intensity was consistently greatest in the vascular endothelium. Real-time qPCR showed a higher OR gene expression in myometrium compared to cervix (P = 0.001) and endometrium (P = 0.009). There was no difference in OR gene expression between cervix and endometrium (P = 1.0). Oxytocin receptor gene expression was significantly higher during the non-luteal phase in both combined uterine tissues (endometrium and myometrium) and myometrium. Oxytocin receptor distribution and gene expression were not influenced by a mare's age or endometrial biopsy score. As endometrial biopsy score and mare age were not predictors of OR gene expression, deficient OR gene expression is unlikely to be associated with DUC.

Transepithelial water flow regulates apical membrane retrieval in antidiuretic hormone-stimulated toad urinary bladder.

Antidiuretic hormone (ADH) increases the osmotic water permeability (Posm) of toad urinary bladder. This increase is believed to be produced by fusion of intracellular vesicles called aggrephores with the granular cell apical plasma membrane. Aggrephores contain intramembrane particle aggregates postulated to be water channels. ADH-stimulated Posm is decreased by osmotic gradient exposure, which is termed flux inhibition. We studied flux inhibition by exposing ADH-stimulated bladders to various osmotic gradients. Osmotic water flow was initially proportional to the applied osmotic gradient, but Posm decreased with time. Ultrastructural and quantitative studies of endocytosis demonstrate that apical membrane retrieval was a direct function of the transepithelial osmotic gradient. Posm remained unchanged when apical membrane retrieval was blocked by incubation of bladders at 2 degrees C, or under low water-flow conditions. These effects were reversed by increases in temperature or the applied osmotic gradient. We conclude that apical membrane retrieval causes the phenomenon of flux inhibition.

Effect of adrenal steroid hormones on the response of the toad's urinary bladder to vasopressin.

This study was designed to examine the effect of adrenal steroid hormones on the response of the toad bladder to vasopressin. Aldosterone enhanced the short-circuit current response, the osmotic water flow response, and the urea permeability response to vasopressin. Since aldosterone also enhanced the short-circuit current response and the osmotic water flow response to adenosine 3',5'-monophosphate, the steroid effect on the bladder's response to vasopressin appears to be at a step beyond the stimulation of adenyl cyclase. Indirect evidence was obtained that the effect of adrenal steroid hormones on the osmotic water flow response to vasopressin is mediated by a different hormone-tissue interaction than that mediating the effect of adrenal steroid hormones on sodium transport. In experiments with three different pairs of mineralocorticoid and glucocorticoid analogues, the former had a greater effect on short-circuit current, the latter on the osmotic water flow response to vasopressin. In addition, the spirolactone SC-14266 markedly inhibited the short-circuit current effect of dexamethasone and had little or no inhibitory effect on the dexamethasone enhancement of the osmotic water flow response to vasopressin. Aldosterone and dexamethasone stimulate the oxidation by the bladder of glucose-6-(14)C and depress the rate of oxidation of glucose-1-(14)C compared with glucose-6-(14)C. SC-14266 inhibited the effect of dexamethasone on the oxidation of glucose-6-(14)C but did not alter the effect of the steroid on the rate of oxidation of glucose-1-(14)C compared with glucose-6-(14)C, suggesting that the latter is a glucocorticoid effect and the stimulation of glucose-6-(14)C oxidation a mineralocorticoid effect. Under conditions in which aldosterone has produced a marked enhancement of short-circuit current and the permeability response to vasopressin, the steroid had no detectable effect on cell water content or on cell sodium, potassium, or chloride.

Vasopressin-stimulated prostaglandin E biosynthesis in the toad urinary bladder. Effect of water flow.

Prostaglandin E biosynthesis and its effect on water permeability were investigated in the toad urinary bladder. Arginine vasopressin (1 mU/ml) increased prostaglandin E (PGE) biosynthesis from 0.5+/-0.1 to 5.0+/-0.4 pmol/min per hemibladder (mean +/-SEM, n= 8, P less than 0.001). Maximal vasopressin-stimulated PGE biosynthesis, 6.4+/-0.2 pmol/min per hemibladder, occurred at vasopressin concentrations in excess of 3 mU/ml. Half-maximal stimulation of PGE biosynthesis occurred at a vasopressin concentration of approximately 0.7 mU/ml, whereas half-maximal stimulation of water flow occurred at a vasopressin concentration of approximately 5 mU/ml. Vasopressin-stimulated PGE biosynthesis did not depend on water flow along an osmotic gradient or upon sodium transport. Thin-layer chromatographic analysis of the lipids released from hemibladders labeled with tritium-arachidonic acid revealed that vasopressin stimulates the release of arachidonic acid from intracellular lipid stores without affecting the percentage of free arachidonic acid converted to PGE. Neither cyclic AMP nor theophylline stimulated PGE biosynthesis although they mimic arginine vasopressin (AVP) in stimulating water permeability. Biosynthesis of PGE was inhibited by mepacrine, a phospholipase inhibitor, and by agents that inhibit arachidonic acid oxygenase. The inhibition of PGE biosynthesis resulted in augmented vasopressin- and theophylline-stimulated water flow, but had no effect on cyclic AMP-stimulated water flow. We interpret these results to mean that endogenous PGE inhibits basal and vasopressin-stimulated adenylate cyclase activity. In contrast to the effects of AVP on permeability and transport, AVP stimulates PGE biosynthesis by a mechanism that does not depend on an increase in cellular cyclic AMP levels. The water permeability response of the toad urinary bladder to vasopressin is inhibited by PGE synthesized by the bladder in response to vasopressin.

Inhibition of vasopressin-stimulated prostaglandin E biosynthesis by chlorpropamide in the toad urinary bladder. Mechanism of enhancement of vasopressin-stimulated water flow.

Chlorpropamide is known to enhance the water permeability response of the toad urinary bladder to vasopressin and to theophylline. In other studies, we have shown that prostaglandin E synthesis by the toad bladder inhibits the water permeability response to arginine vasopressin and to theophylline. In this study, the effect of chlorpropamide on vasopressin-, theophylline-, and cyclic AMP-stimulated water flow and on prostaglandin E biosynthesis was investigated in the toad urinary bladder in vitro. Chlorpropamide inhibited prostaglandin E biosynthesis during vasopressin-, theophylline- and cyclic AMP-stimulated water flow. Tolbutamide and glyburide, two other sulfonylurea compounds, also enhanced vasopressin-stimulated water flow and inhibited vasopressin-stimulated prostaglandin E biosynthesis. We conclude that the mechanism of enhancement on vasopressin-stimulated water flow by the sulfonylureas is the inhibition of prostaglandin E biosynthesis.

Taurine behaves as an osmolyte in Madin-Darby canine kidney cells. Protection by polarized, regulated transport of taurine.

Using a clonal growth assay, we demonstrated that taurine, a nonperturbing osmolyte accumulated in kidney medulla, brain, and some other tissues of hypertonic experimental animals can function as a nonperturbing osmolyte in Madin-Darby canine kidney (MDCK) cells. The taurine content of hypertonic MDCK cells is twice that of isotonic MDCK cells (isotonic 160 nmol/mg protein; hypertonic 320 nmol/mg protein). Therefore we studied taurine transport in MDCK cells grown on porous supports and then studied the effect of hypertonicity which is known to elicit increased uptake of some other nonperturbing osmolytes by MDCK cells. Basal uptake exceeded apical uptake, with Km and Vmax of 56 microM and 933 pmol/min.mg protein on the basal surface and 10 microM and 50 pmol/min.mg protein on the apical surface. On both surfaces, virtually all taurine uptake was Na+ and Cl- dependent. 24 h after cells were shifted to hypertonic medium (500 mosmol/kg), taurine uptake doubled on the basolateral surface without change on the apical surface. The response to hypertonicity was the result of an increase in Vmax without change in Km. There was no change in taurine efflux when cells were shifted from isotonic to hypertonic medium. When cells adapted to hypertonic medium were shifted to isotonic medium, a large transient basolateral efflux of taurine occurred within 10 min. We conclude that taurine can function as a nonperturbing osmolyte in MDCK cells and that tonicity-regulated taurine transport is a basolateral function in MDCK cells.

Medium tonicity regulates expression of the Na(+)- and Cl(-)-dependent betaine transporter in Madin-Darby canine kidney cells by increasing transcription of the transporter gene.

Betaine is one of the major compatible osmolytes accumulated by kidney derived Madin-Darby canine kidney cells cultured in hypertonic medium. Betaine is accumulated by Na(+)- and Cl(-)-dependent uptake from the medium. To gain insight into the mechanism by which hypertonicity evokes an increase in the Vmax of the betaine transporter in Madin-Darby canine kidney cells, we measured the relative abundance of mRNA for the transporter in cells shifted to a hypertonic medium and found parallel increases in mRNA abundance and cotransporter activity. The increase in mRNA levels preceded the increase in transporter activity slightly. Transcription of the gene for the transporter rose rapidly and to the same relative extent as mRNA abundance in cells shifted to hypertonic medium, indicating that transcription of the gene for the cotransporter plays a major role in regulating the accumulation of betaine in response to hypertonicity.

[Plasma concentrations of folic acid, vitamin B12 and progesterone of cyclic bitches, bitches during pregnancy and induced abortion and bitches with pyometra]. / Plasmakonzentrationen von Folsäure, Vitamin B12 und Progesteron während des Sexualzyklus, Gravidität, Abortinduktion und Pyometra bei der Hündin.

The aim of this study was to investigate the plasma concentrations of folic acid, vitamin B12 and progesterone at different stages of the sexual cycle and pregnancy, during induced abortion and in bitches with pyometra. Bitches (n = 97) were assigned to groups as follows: a) oestrous cycle (n = 42) b) pregnancy (n = 25) c) induction of abortion (n = 10 and d) pyometra (n = 20). Oestrous cycle stages were determined by vaginal inspection and cytology. Pregnancies were estimated by ultrasound (5.0 Mhz; linear transducer; Schimadzu) at days 15-25, 35-45 and 46-63 of pregnancy. Treatments for the induction of abortion were started between days 25 and 35 after mating (5 microg/kg cabergoline daily, Galastop; 5-10 microg/kg Alfaprostol every other day, Gabbrostim). Diagnosis of pyometra was confirmed by ultrasound and vaginoscopy. Folic acid and vitamin B12 concentrations did not differ among different stages of the oestrous cycle. The mean concentration of folic acid during early pregnancy (days 15-25) exceeded levels of later stages (days 46-63): 9.4 +/- 3.7 microg/ml and 4.7 +/- 1.8 microg/ml, respectively (p < 0.01). A positive correlation between folic acid and vitamin B12 was determined in pregnant dogs ( r = 0.925; p < 0.02). Before the induction of abortion, the concentration of folic acid was 9.6 +/- 5.2 microg/ml; during abortion it decreased to 5.0 +/- 3.2 microg/ml (p < 0.01). A significant correlation (r = 0.925; p < 0.02) between progesterone and folic acid was obtained in bitches with abortion. The mean concentration of folic acid in bitches with pyometra significantly differed from that of bitches at different stages of the oestrous cycle (p < 0.05). The mean concentration of folic acid was significantly lower in metoestrous bitches when compared to bitches with pyometra (p < 0.05). The decrease of serum concentrations of folic acid during pregnancy and induced abortion show that fetal growth and abortion caused higher consumption of folic acid. Concerning bitches did not show any deficiency symptoms, which is why it can be concluded that this decrease is physiological.

Effect of parathyroid hormone and cyclic AMP on protein phosphorylation in rabbit kidney cortex.

Suspensions of renal cortical tubules were incubated with 33Pi and exposed to parathyroid hormone (40 mlg/ml) or 1 mM dibutyryl cyclic AMP. In other experiments homogenates of renal cortex were assayed for protein kinase and phosphoprotein phosphatase activity using [gamma-32P]ATP with or without 5 mM cyclic AMP. Proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and phosphorylation of proteins measured by liquid scintillation counting of gel slices. The pattern of protein phosphorylation was similar in control tissue from both tubule suspensions and homogenates. In intact tubules, parathyroid hormone stimulated the phosphorylation of four proteins with molecular weights of approx. 150 000, 125 000, 100 000 and 50 000 by 28%, 24%, 13%, and 20%, respectively. Results with dibutyryl cyclic AMP were comparable but more variable. Stimulation of phosphorylation by cyclic AMP in homogenates was more generalized with the major effect on a 50 000 dalton protein (50% stimulation). No effect of cyclic AMP on dephosphorylation of proteins was observed. The results are interpreted as indicating that increased phosphorylation of cell proteins is part of the cyclic AMP-mediated response of the renal cortex to parathyroid hormone.

Identification of the second tonicity-responsive enhancer for the betaine transporter (BGT1) gene.

When certain cells are exposed to a hypertonic solution, transcription of the BGT1 gene is markedly increased. The ensuing rise in betaine transport leads to cellular accumulation of betaine that protects the cells from the stress of hypertonicity. We have previously identified a tonicity-responsive enhancer (TonE1) in the 5' flanking region of the BGT1 gene. It was recognized, however, that full activation of transcription requires additional sequence upstream from the TonE1. Now we report that there is another TonE (named TonE2) 72 base pairs upstream from the TonE1. TonE1 and TonE2 act synergistically to stimulate transcription of BGT1 in response to hypertonicity.

Aldosterone-induced proteins in renal epithelia.

Similar aldosterone-induced proteins have been demonstrated in two renal epithelia, the urinary bladder of the toad, Bufo marinus, and epithelia formed by cells of the A6 line derived from the kidney of the toad, Xenopus laevis. The proteins are induced along with the stimulation of Na+ transport but their synthesis is not dependent on Na+ transport per se. In view of the similar characteristics of the aldosterone-induced proteins in these two different epithelia, we suggest that they may have an important role in aldosterone-induced Na+ transport.

Transepithelial transport of vinblastine by kidney-derived cell lines. Application of a new kinetic model to estimate in situ Km of the pump.

We present a new transport model that may be useful for many kinds of transepithelial transport experiments. The model permits estimation of a pump Km and pump activity solely on the basis of transepithelial tracer fluxes. We apply the model to studies of a multidrug efflux pump, P-glycoprotein, which is normally located in the apical plasma membrane of certain transporting epithelia such as kidney proximal tubule cells. To determine the functional properties of this multidrug transporter in an epithelium, we studied the transepithelial transport of the chemotherapeutic drug, vinblastine, in epithelia formed by the kidney cell lines MDCK, LLC-PK1, and OK. We have previously shown that basal to apical flux of 100 nM vinblastine was about five times higher than apical to basal flux in MDCK epithelia, indicating that there is a net transepithelial transport of vinblastine across MDCK epithelia. Addition of unlabeled vinblastine reduced basal to apical flux of tracer and increased apical to basal flux of tracer in a concentration-dependent manner, a pattern expected if there is a saturable pump that extrudes vinblastine at the apical plasma membrane. The model permits estimation of a pump Km and pump activity solely on the basis of transepithelial tracer fluxes. According to the transport model the apical membrane pump has Michaelis-Menten kinetics with an apparent Km = 1.1 microM. Net basal to apical transport of vinblastine was also observed in LLC-PK1 cells and OK cells which are other kidney-derived cell lines. The order of potency of the transport is LLC-PK1 greater than MDCK greater than OK cells. The organic cation transporter is not involved in this vinblastine transport because vinblastine transport in MDCK cells was not affected by 3 mM tetramethyl- or tetraethylammonium. Inhibitors of vinblastine transport in MDCK cells was not affected by potency, were verapamil greater than vincristine greater than actinomycin D greater than daunomycin. The transport pattern we observed is that predicted to result from the function of the multidrug transporter in the apical plasma membrane.

Gangliosides do not move from apical to basolateral plasma membrane in cultured epithelial cells.

Both qualitative and quantitative approaches were used to ascertain whether gangliosides, incorporated into the apical plasma membrane of cultured epithelial cells from kidney of toad (A6) and dog (MDCK), were able to redistribute past the tight junctions to the basolateral membrane. The apical surfaces of confluent epithelia were exposed to rhodaminyl gangliosides and the distribution of the inserted gangliosides was assessed qualitatively by fluorescence microscopy. All of the fluorescence was confined to the apical surface for at least 1 h after the fluorescent gangliosides had become incorporated; none appeared on the basolateral surface. These observations were confirmed by incubating the cells with anti-rhodamine antibodies and 125I-labeled protein A. In order to quantitate further the ganglioside distribution, binding assays were performed using 125I-labeled cholera toxin, which binds specifically to ganglioside GM1. Exogenous GM1 added to the apical membrane was not detected on the basolateral membrane 4 h after its incorporation even though there was extensive disappearance of the inserted ganglioside, presumably through endocytosis. To directly examine the behaviour of endogenous gangliosides, the apical surface of the epithelial cells was exposed to bacterial neuraminidase, which hydrolyzes more complex gangliosides to GM1. The cells exhibited a 10-fold increase in binding of cholera toxin to their apical surface, but no increase in binding to their basolateral surface. Thus, no cellular pathways for movement from apical to basolateral plasma membrane appear to be available for implanted or endogenous gangliosides.

Matrix metalloproteinase 2 (MMP-2) and tissue transglutaminase (TG 2) are expressed in periglandular fibrosis in horse mares with endometrosis.

Periglandular arrangement of myofibroblasts, associated with the deposition of extracellular matrix (ECM), is a cardinal feature of endometrosis in mares. We hypothesized that a disturbance in the expression of matrix degrading enzymes such as matrix metalloproteinases (MMP's) and matrix cross-linking proteins might lead to an imbalance in deposition and degradation of extracellular matrix components and thereby accentuate degeneration. Therefore, distributions of MMP-2, capable of collagen IV and laminin degradation, and tissue transglutaminase (TG2), a cross-linker of extracellular matrix proteins, were investigated by means of immunohistochemistry on uterine biopsies of healthy mares and animals with endometrosis. It was illustrated that both proteins were present in fibrotic regions of affected endometria, and that they were in most cases colocalized. Periglandular MMP-2 expression was significantly associated with dilated and fibrotic uterine glands. Furthermore, MMP-2 and TG 2 were demonstrated in the stratum compactum of healthy and endometrotic endometria. Gelatin zymography proved that active and inactive pro-form of MMP-2 were present in all examined samples with significantly higher amounts of total and active MMP-2 in affected endometria. TG 2-activity, determined by an in situ assay, was found in cases of severe periglandular fibrosis. We suggest that both enzymes play a major role in changes that occur in ECM homeostasis in endometrial fibrotic regions.