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1.
BMC Oral Health ; 22(1): 553, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36457084

RESUMEN

BACKGROUND: Orofacial clefts are characterized by a frequent occurrence of dental anomalies. Numerous studies demonstrate the high prevalence of dental aplasia, supernumerary teeth, and hypoplastic teeth in patients with cleft lip with/without cleft palate (CL/P), yet the therapeutic consequences are rarely discussed. This study explores prevalence, localization, and association between primary and secondary dentition in a large European collective and begins to evaluate the significance of dental anomalies in the therapeutic course of patients with CL/P. METHODS: The medical reports of 1070 patients with different entities of CL/P who presented to our clinic within a 15-year investigation period were evaluated retrospectively. Dental anomalies were classified into three different diagnostic groups: dental aplasia, supernumerary teeth and hypoplastic teeth. The statistical analyses included studies of the frequency and localization of dental anomalies in different cleft entities as well as of the association between primary and secondary dentition and the therapeutic consequences. RESULTS: Uni- or bilateral cleft lip and palate (CLP) (47.5%) occurred most frequently, followed by cleft palate only (CPO) (32.9%) and cleft lip with or without alveolus (CL ± A) (19.6%). Dental anomalies were found significantly more often on the side of the cleft. Aplastic permanent teeth were mostly found in patients with CLP (54.8%), while supernumerary permanent teeth occurred primarily in patients with CL ± A (21.7%). Patients with CPO presented dental aplasia but no patient with CPO showed supernumerary teeth. The occurrence of dental aplasia in the primary dentition significantly increases the probability of aplastic teeth in the permanent dentition. Dental anomalies, in particular dental aplasia, significantly increase patients' need for subsequent orthodontic therapy and orthognathic surgery. CONCLUSION: Dental aplasia and hypoplasia are common in patients with CL/P not only in the cleft area but in the whole dentition. In the event of dental aplasia in the primary dentition, the frequency of aplastic teeth in the permanent dentition is significantly higher. Additionally, the need for therapeutic interventions, especially concerning orthognathic surgery, seems to be significantly higher in patients with CL/P who are affected by dental anomalies. Clinicians should take this into account when creating long-term treatment plans.


Asunto(s)
Labio Leporino , Fisura del Paladar , Diente Supernumerario , Humanos , Labio Leporino/complicaciones , Labio Leporino/epidemiología , Fisura del Paladar/complicaciones , Fisura del Paladar/epidemiología , Estudios Retrospectivos , Diente Supernumerario/complicaciones , Diente Supernumerario/epidemiología
2.
Soft Matter ; 15(5): 956-962, 2019 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-30652170

RESUMEN

Saccharide diesters have been recently shown to be excellent gelators of vegetable oils. In this paper, different fatty acid trehalose diesters were synthesized by a selective enzymatic transesterification performed only on the primary hydroxyl group of the trehalose. The resulting trehalose diesters demonstrated their ability to self-assemble in a large variety of edible vegetable oils with a minimum gelation concentration of 0.25 wt%/v. Microscopic analysis and X-ray scattering studies indicate that the gels are obtained by the self-assembly of trehalose diesters in crystalline fibers constituting the tridimensional network. The rheological study revealed that the properties of the gels depend on the kind of fatty acid grafted on the trehalose but are also influenced by the vegetable oil composition.

3.
Eur Phys J E Soft Matter ; 41(9): 107, 2018 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-30219930

RESUMEN

The adsorption of the 5-Fluorouracil (5-FU) molecule on the pristine and Al-doped activated carbon (AC) was investigated by using the Vienna Ab-initio Simulation Package. It is found that the 5-FU molecule is only weakly adsorbed on the pristine AC with high adsorption energy and large surface distance. The adsorption of the 5-FU molecule on pristine AC is highly disfavored. In contrast, the molecule shows strong interactions with the Al-doped AC confirmed by the lesser adsorption energy, the charge transfers on the Al-modified zone and the significant changes in the DOS at the Fermi level. The results of our study suggest that the Al dopant increases the adsorption capacity of AC enhancing its interactions with polar atoms of the adsorbate, hence improving its adsorption properties.


Asunto(s)
Aluminio/química , Antineoplásicos/química , Carbón Orgánico/química , Fluorouracilo/química , Teoría Cuántica , Adsorción , Modelos Moleculares , Conformación Molecular
4.
Gen Comp Endocrinol ; 257: 168-176, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28652133

RESUMEN

Osmoregulation in vertebrates is largely controlled by the neuroendocrine system. Prolactin (PRL) is critical for the survival of euryhaline teleosts in fresh water by promoting ion retention. In the euryhaline Mozambique tilapia (Oreochromis mossambicus), pituitary PRL cells release two PRL isoforms, PRL188 and PRL177, in response to a fall in extracellular osmolality. Both PRLs function via two PRL receptors (PRLRs) denoted PRLR1 and PRLR2. We conducted a comparative study using the Nile tilapia (O. niloticus), a close relative of Mozambique tilapia that is less tolerant to increases in environmental salinity, to investigate the regulation of PRLs and PRLRs upon acute hyperosmotic challenges in vivo and in vitro. We hypothesized that differences in the regulation of PRLs and PRLRs underlie the variation in salinity tolerance of tilapias within the genus Oreochromis. When transferred from fresh water to brackish water (20‰), Nile tilapia increased plasma osmolality and decreased circulating PRLs, especially PRL177, to a greater extent than Mozambique tilapia. In dispersed PRL cell incubations, the release of both PRLs was less sensitive to variations in medium osmolality in Nile tilapia than in Mozambique tilapia. By contrast, increases in pituitary and branchial prlr2 gene expression in response to a rise in extracellular osmolality were more pronounced in Nile tilapia relative to its congener, both in vitro and in vivo. Together, these results support the conclusion that inter-specific differences in salinity tolerance between the two tilapia congeners are tied, at least in part, to the distinct responses of both PRLs and their receptors to osmotic stimuli.


Asunto(s)
Cíclidos , Prolactina/metabolismo , Receptores de Prolactina/metabolismo , Animales , Concentración Osmolar , Osmorregulación , Salinidad
5.
Gen Comp Endocrinol ; 240: 227-237, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-27449341

RESUMEN

Leptin is an important cytokine for regulating energy homeostasis, however, relatively little is known about its function and control in teleost fishes or other ectotherms, particularly with regard to interactions with the growth hormone (GH)/insulin-like growth factors (IGFs) growth regulatory axis. Here we assessed the regulation of LepA, the dominant paralog in tilapia (Oreochromis mossambicus) and other teleosts under altered nutritional state, and evaluated how LepA might alter pituitary growth hormone (GH) and hepatic insulin-like growth factors (IGFs) that are known to be disparately regulated by metabolic state. Circulating LepA, and lepa and lepr gene expression increased after 3-weeks fasting and declined to control levels 10days following refeeding. This pattern of leptin regulation by metabolic state is similar to that previously observed for pituitary GH and opposite that of hepatic GHR and/or IGF dynamics in tilapia and other fishes. We therefore evaluated if LepA might differentially regulate pituitary GH, and hepatic GH receptors (GHRs) and IGFs. Recombinant tilapia LepA (rtLepA) increased hepatic gene expression of igf-1, igf-2, ghr-1, and ghr-2 from isolated hepatocytes following 24h incubation. Intraperitoneal rtLepA injection, on the other hand, stimulated hepatic igf-1, but had little effect on hepatic igf-2, ghr1, or ghr2 mRNA abundance. LepA suppressed GH accumulation and gh mRNA in pituitaries in vitro, but had no effect on GH release. We next sought to test if abolition of pituitary GH via hypophysectomy (Hx) affects the expression of hepatic lepa and lepr. Hypophysectomy significantly increases hepatic lepa mRNA abundance, while GH replacement in Hx fish restores lepa mRNA levels to that of sham controls. Leptin receptor (lepr) mRNA was unchanged by Hx. In in vitro hepatocyte incubations, GH inhibits lepa and lepr mRNA expression at low concentrations, while higher concentration stimulates lepa expression. Taken together, these findings indicate LepA gene expression and secretion increases with fasting, consistent with the hormones function in promoting energy expenditure during catabolic stress. It would also appear that LepA might play an important role in stimulating GHR and IGFs to potentially spare declines in these factors during catabolism. Evidence also suggests for the first time in teleosts that GH may exert important regulatory effects on hepatic LepA production, insofar as physiological levels (0.05-1 nM) suppresse lepa mRNA accumulation. Leptin A, may in turn exert negative feedback effects on basal GH mRNA abundance, but not secretion.


Asunto(s)
Hormona del Crecimiento/metabolismo , Factor II del Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Leptina/metabolismo , Hígado/metabolismo , Receptores de Somatotropina/metabolismo , Tilapia/metabolismo , Animales , Peso Corporal/efectos de los fármacos , Ayuno , Conducta Alimentaria/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Hipofisectomía , Masculino , Hipófisis/efectos de los fármacos , Hipófisis/metabolismo , ARN Mensajero/genética , Receptores de Somatotropina/genética
6.
Artículo en Inglés | MEDLINE | ID: mdl-27032617

RESUMEN

The growth hormone (GH)/insulin-like growth factor (IGF) axis plays a central role in the regulation of growth in teleosts and has been shown to be affected by acclimation salinity. This study was aimed at characterizing the effects of rearing tilapia, Oreochromis mossambicus, in a tidally-changing salinity on the GH/IGF axis and growth. Tilapia were raised in fresh water (FW), seawater (SW), or in a tidally-changing environment, in which salinity is switched between FW (TF) and SW (TS) every 6h, for 4months. Growth was measured over all time points recorded and fish reared in a tidally-changing environment grew significantly faster than other groups. The levels of circulating growth hormone (GH), insulin-like growth factor I (IGF-I), pituitary GH mRNA, gene expression of IGF-I, IGF-II, and growth hormone receptor 2 (GHR) in the muscle and liver were also determined. Plasma IGF-I was higher in FW and TS than in SW and TF tilapia. Pituitary GH mRNA was higher in TF and TS than in FW and SW tilapia. Gene expression of IGF-I in the liver and of GHR in both the muscle and liver changed between TF and TS fish. Fish growth was positively correlated with GH mRNA expression in the pituitary, and GHR mRNA expression in muscle and liver tissues. Our study indicates that rearing fish under tidally-changing salinities elicits a distinct pattern of endocrine regulation from that observed in fish reared in steady-state conditions, and may provide a new approach to increase tilapia growth rate and study the regulation of growth in euryhaline fish.


Asunto(s)
Hormona del Crecimiento/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Tilapia/fisiología , Alimentación Animal , Animales , Acuicultura , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Regulación de la Expresión Génica , Hormona del Crecimiento/genética , Factor I del Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/genética , Hígado/fisiología , Músculos/fisiología , Hipófisis/metabolismo , Receptores de Somatotropina/genética , Salinidad , Tilapia/crecimiento & desarrollo , Tilapia/metabolismo
7.
Artículo en Inglés | MEDLINE | ID: mdl-27210417

RESUMEN

In euryhaline teleosts, reorganization of gill tight junctions during salinity acclimation involves dynamic expression of specific claudin (Cldn) paralogs. We identified four transcripts encoding Cldn tight junction proteins in the tilapia gill transcriptome: cldn10c, cldn10e, cldn28a and cldn30. A tissue distribution experiment found cldn10c and cldn10e expression levels in the gill to be 100-fold higher than any other tissues examined. cldn28a and cldn30 levels in the gill were 10-fold greater than levels in other tissues. Expression of these genes in Mozambique tilapia was examined during acclimation to fresh water (FW), seawater (SW), and in response to hormone treatments. Transfer of tilapia from FW to SW elevated cldn10c and cldn10e, while cldn28a and cldn30 were stimulated following transfer from SW to FW. In hypophysectomized tilapia transferred to FW, pituitary extirpation induced reduced expression of cldn10c, cldn10e and cldn28a; these effects were mitigated equally by either prolactin or cortisol replacement. In vitro experiments with gill filaments showed that cortisol stimulated expression of all four cldns examined, suggesting a direct action of cortisol in situ. Our data indicate that elevated cldn10c and cldn10e expression is important during acclimation of tilapia to SW possibly by conferring ion specific paracellular permeability. On the other hand, expression of cldn28a and cldn30 appears to contribute to reorganization of branchial epithelium during FW acclimation. Hormone treatment experiments showed that particular FW- and SW-induced cldns are controlled by cortisol and prolactin.


Asunto(s)
Claudinas/genética , Proteínas de Peces/genética , Branquias/efectos de los fármacos , Hidrocortisona/farmacología , Prolactina/farmacología , Tilapia/genética , Animales , Agua Dulce , Regulación de la Expresión Génica/efectos de los fármacos , Branquias/metabolismo , Hipofisectomía , Técnicas In Vitro , Isoformas de Proteínas/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Salinidad , Agua de Mar , Transcriptoma/efectos de los fármacos
8.
Am J Physiol Regul Integr Comp Physiol ; 309(10): R1251-63, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26377558

RESUMEN

This study characterized the local effects of extracellular osmolality and prolactin (PRL) on branchial ionoregulatory function of a euryhaline teleost, Mozambique tilapia (Oreochromis mossambicus). First, gill filaments were dissected from freshwater (FW)-acclimated tilapia and incubated in four different osmolalities, 280, 330, 380, and 450 mosmol/kg H2O. The mRNA expression of Na(+)/K(+)-ATPase α1a (NKA α1a) and Na(+)/Cl(-) cotransporter (NCC) showed higher expression with decreasing media osmolalities, while Na(+)/K(+)/2Cl(-) cotransporter 1a (NKCC1a) and PRL receptor 2 (PRLR2) mRNA levels were upregulated by increases in media osmolality. We then incubated gill filaments in media containing ovine PRL (oPRL) and native tilapia PRLs (tPRL177 and tPRL188). oPRL and the two native tPRLs showed concentration-dependent effects on NCC, NKAα1a, and PRLR1 expression; Na(+)/H(+) exchanger 3 (NHE3) expression was increased by 24 h of incubation with tPRLs. Immunohistochemical observation showed that oPRL and both tPRLs maintained a high density of NCC- and NKA-immunoreactive ionocytes in cultured filaments. Furthermore, we found that tPRL177 and tPRL188 differentially induce expression of these ion transporters, according to incubation time. Together, these results provide evidence that ionocytes of Mozambique tilapia may function as osmoreceptors, as well as directly respond to PRL to modulate branchial ionoregulatory functions.


Asunto(s)
Transporte Iónico/fisiología , Concentración Osmolar , Prolactina/farmacología , Simportadores del Cloruro de Sodio/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Tilapia/fisiología , Animales , Matriz Extracelular , Regulación de la Expresión Génica/fisiología , Branquias , Masculino , Receptores de Prolactina/genética , Receptores de Prolactina/metabolismo , Simportadores del Cloruro de Sodio/genética , Regulación hacia Arriba
9.
J Exp Biol ; 218(Pt 5): 731-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25617466

RESUMEN

This study characterizes the differences in osmoregulatory capacity among Mozambique tilapia, Oreochromis mossambicus, reared in freshwater (FW), in seawater (SW) or under tidally driven changes in salinity. This was addressed through the use of an abrupt exposure to a change in salinity. We measured changes in: (1) plasma osmolality and prolactin (PRL) levels; (2) pituitary expression of prolactin (PRL) and its receptors, PRLR1 and PRLR2; (3) branchial expression of PRLR1, PRLR2, Na(+)/Cl(-) co-transporter (NCC), Na(+)/K(+)/2Cl(-) co-transporter (NKCC), α1a and α1b isoforms of Na(+)/K(+)-ATPase (NKA), cystic fibrosis transmembrane conductance regulator (CFTR), aquaporin 3 (AQP3) and Na(+)/H(+) exchanger 3 (NHE3). Mozambique tilapia reared in a tidal environment successfully adapted to SW while fish reared in FW did not survive a transfer to SW beyond the 6 h sampling. With the exception of CFTR, the change in the expression of ion pumps, transporters and channels was more gradual in fish transferred from tidally changing salinities to SW than in fish transferred from FW to SW. Upon transfer to SW, the increase in CFTR expression was more robust in tidal fish than in FW fish. Tidal and SW fish successfully adapted when transferred to FW. These results suggest that Mozambique tilapia reared in a tidally changing salinity, a condition that more closely represents their natural history, gain an adaptive advantage compared with fish reared in FW when facing a hyperosmotic challenge.


Asunto(s)
Branquias/metabolismo , Hipófisis/metabolismo , Tilapia/crecimiento & desarrollo , Aclimatación , Animales , Acuaporina 3/metabolismo , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Agua Dulce , Osmorregulación , Prolactina/metabolismo , Receptores de Prolactina/metabolismo , Salinidad , Agua de Mar , Simportadores de Cloruro de Sodio-Potasio/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Tilapia/metabolismo , Movimientos del Agua , Equilibrio Hidroelectrolítico
10.
Gen Comp Endocrinol ; 224: 216-27, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26320855

RESUMEN

The conventional prolactin (PRL), also known as PRL1, is an adenohypophysial hormone that critically regulates various physiological events in reproduction, metabolism, growth, osmoregulation, among others. PRL1 shares its evolutionary origin with PRL2, growth hormone (GH), somatolactin and placental lactogen, which together form the GH/PRL hormone family. Previously, several bioassays implied the existence of PRL1 in elasmobranch pituitaries. However, to date, all attempts to isolate PRL1 from chondrichthyans have been unsuccessful. Here, we cloned PRL1 from the pituitary of the holocephalan elephant fish, Callorhinchus milii, as the first report of chondrichthyan PRL1. The putative mature protein of elephant fish PRL1 (cmPRL1) consists of 198 amino acids, containing two conserved disulfide bonds. The orthologous relationship of cmPRL1 to known vertebrate PRL1s was confirmed by the analyses of molecular phylogeny and gene synteny. The cmPRL1 gene was similar to teleost PRL1 genes in gene synteny, but was distinct from amniote PRL1 genes, which most likely arose in an early amphibian by duplication of the ancestral PRL1 gene. The mRNA of cmPRL1 was predominantly expressed in the pituitary, but was considerably less abundant than has been previously reported for bony fish and tetrapod PRL1s; the copy number of cmPRL1 mRNA in the pituitary was less than 1% and 0.1% of that of GH and pro-opiomelanocortin mRNAs, respectively. The cells expressing cmPRL1 mRNA were sparsely distributed in the rostral pars distalis. Our findings provide a new insight into the studies on molecular and functional evolution of PRL1 in vertebrates.


Asunto(s)
Evolución Biológica , Pez Eléctrico/metabolismo , Evolución Molecular , Filogenia , Hipófisis/metabolismo , Prolactina/metabolismo , Secuencia de Aminoácidos , Animales , Clonación Molecular , Pez Eléctrico/crecimiento & desarrollo , Hibridación in Situ , Datos de Secuencia Molecular , Hipófisis/citología , Homología de Secuencia de Aminoácido , Distribución Tisular
11.
Artículo en Inglés | MEDLINE | ID: mdl-26021981

RESUMEN

Recently, a teleost ortholog of renal outer medullary K(+) channel (ROMK) expressed in gill ionocytes (ROMKa) has emerged as a primary K(+)-excreting pathway in fish. However, the mechanisms by which ROMKa expression is regulated in response to perturbations of plasma K(+) levels are unknown. In this study, we aimed to identify potential links between the endocrine system and K(+) regulation in a euryhaline fish. We assessed time-course changes in multiple endocrine parameters, including plasma cortisol and gene expression of branchial glucocorticoid and mineralocorticoid receptors (GR1, GR2, and MR) and pituitary hormones, in seawater (SW)-acclimated Mozambique tilapia (Oreochromis mossambicus) exposed to high-K(+) (H-K) SW. Exposure to H-K SW elicited little effects on plasma cortisol or mRNA levels of GRs and pituitary hormones. Since plasma K(+) and branchial ROMKa expression was increased within 6h after H-K treatment in vivo, the effect of high K(+) was subsequently tested in a gill filament incubation experiment using media with differing K(+) concentrations. ROMKa mRNA levels were induced following incubation of filaments in H-K medium for 6h. The present study is the first to demonstrate that the expression of ROMKa in teleost ionocytes can respond to high K(+) conditions independent from systemic signaling.


Asunto(s)
Adaptación Fisiológica , Canales de Potasio/metabolismo , Potasio/metabolismo , Agua de Mar , Tilapia/fisiología , Animales , Hidrocortisona/sangre , Técnicas In Vitro , Receptores de Glucocorticoides/genética , Receptores de Mineralocorticoides/genética
12.
Gen Comp Endocrinol ; 207: 94-102, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24681189

RESUMEN

The native distribution of Mozambique tilapia, Oreochromis mossambicus, is characterized by estuarine areas subject to salinity variations between fresh water (FW) and seawater (SW) with tidal frequency. Osmoregulation in the face of changing environmental salinity is largely mediated through the neuroendocrine system and involves the activation of ion uptake and extrusion mechanisms in osmoregulatory tissues. We compared plasma osmolality, plasma prolactin (PRL), pituitary PRL mRNA, and mRNA of branchial ion pumps, transporters, channels, and PRL receptors in tilapia reared in FW, SW, brackish water (BW) and in tidally-changing salinity, which varied between FW (TF) and SW (TS) every 6h. Plasma PRL was higher in FW tilapia than in SW, BW, TF, and TS tilapia. Unlike tilapia reared in FW or SW, fish in salinities that varied tidally showed no correlation between plasma osmolality and PRL. In FW fish, gene expression of PRL receptor 1 (PRLR1), Na(+)/Cl(-) cotransporter (NCC), aquaporin 3 (AQP3) and two isoforms of Na(+)/K(+)-ATPase (NKA α1a and NKA α1b) was higher than that of SW, BW or tidally-changing salinity fish. Gene expression of the Na(+)/K(+)/2Cl(-) cotransporter (NKCC1a), and the cystic fibrosis transmembrane conductance regulator (CFTR) were higher in fish in SW, BW or a tidally-changing salinity than in FW fish. Immunocytochemistry revealed that ionocytes of fish in tidally-changing salinities resemble ionocytes of SW fish. This study indicated that tilapia reared in a tidally-changing salinity can compensate for large changes in external osmolality while maintaining osmoregulatory parameters within a narrow range closer to that observed in SW-acclimated fish.


Asunto(s)
Aclimatación/fisiología , Hipófisis/metabolismo , Salinidad , Tilapia/crecimiento & desarrollo , Movimientos del Agua , Animales , Acuaporina 3/genética , Acuaporina 3/metabolismo , Agua Dulce , Técnicas para Inmunoenzimas , Transporte Iónico , Prolactina/genética , Prolactina/metabolismo , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Prolactina/genética , Receptores de Prolactina/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Agua de Mar , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Tilapia/metabolismo , Equilibrio Hidroelectrolítico/fisiología
13.
Gen Comp Endocrinol ; 207: 86-93, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24662392

RESUMEN

The present study identifies regulatory interactions between leptin A (LepA) and the pituitary hormone prolactin (PRL). In order to measure tilapia (Oreochromis mossambicus) LepA, an enzyme-linked immunosorbent assay (ELISA) utilizing a rabbit polyclonal antibody specific to tilapia LepA was first developed. The antibody shows strong cross reactivity to recombinant tilapia LepA (rtLepA), and a corresponding 16kDa protein in both tilapia and striped bass plasma, but not to recombinant human leptin (rhLep). The assay has a linear detection range of 0.25-1000nM, with intra- and interassay variability of 9% and 16%, respectively. Plasma LepA levels measured in tilapia ranged from 0.8 to 3.9nM, similar to that found for other vertebrates. Hypophysectomy (Hx) increased circulating LepA and lepa mRNA levels in the liver, the dominant source of hormone production. Adminstration of ovine PRL (oPRL, 5µg/g BW) to Hx fish restored circulating LepA and hepatic lepa mRNA levels to those of control fish. Additionally, oPRL reduced lepa mRNA levels in a dose-dependent fashion in cultured hepatocytes following an 18h incubation. Previous work in our lab indicates that rhLep stimulates PRL release in vitro from tilapia pituitaries. Here, both rtLepA and rhLep (0.5µg/g BW) increased mRNA expression of tilapia prolactin mRNAs (prl1, prl2) in the pituitary in vivo. These results demonstrate that LepA enhances pituitary prolactin synthesis and release, while PRL in turn inhibits hepatic leptin secretion and synthesis in teleosts. We postulate this regulatory interaction may be necessary for mobilizing energy reserves during acute hyperosmotic adaptation.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Leptina/metabolismo , Hipófisis/metabolismo , Prolactina/farmacología , Tilapia/metabolismo , Aclimatación , Animales , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Humanos , Hipofisectomía , Leptina/antagonistas & inhibidores , Leptina/genética , Hígado/efectos de los fármacos , Hígado/metabolismo , Hipófisis/efectos de los fármacos , ARN Mensajero/genética , Conejos , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tilapia/crecimiento & desarrollo
14.
Gen Comp Endocrinol ; 207: 66-73, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24818968

RESUMEN

Growth in teleosts is controlled in large part by the activities of the growth hormone (Gh)/insulin-like growth factor (Igf) system. In this study, we initially identified igf-binding protein (bp)1b, -2b, -4, -5a and -6b transcripts in a tilapia EST library. In Mozambique tilapia (Oreochromis mossambicus), tissue expression profiling of igfbps revealed that igfbp1b and -2b had the highest levels of expression in liver while igfbp4, -5a and -6b were expressed at comparable levels in most other tissues. We compared changes in hepatic igfbp1b, -2b and -5a expression during catabolic conditions (28days of fasting) along with key components of the Gh/Igf system, including plasma Gh and Igf1 and hepatic gh receptor (ghr2), igf1 and igf2 expression. In parallel with elevated plasma Gh and decreased Igf1 levels, we found that hepatic igfbp1b increased substantially in fasted animals. We then tested whether systemic Gh could direct the expression of igfbps in liver. A single intraperitoneal injection of ovine Gh into hypophysectomized tilapia specifically stimulated liver igfbp2b expression along with plasma Igf1 and hepatic ghr2 levels. Our collective data suggest that hepatic endocrine signaling during fasting may involve post-translational regulation of plasma Igf1 via a shift towards the expression of igfbp1b. Thus, Igfbp1b may operate as a molecular switch to restrict Igf1 signaling in tilapia; furthermore, we provide new details regarding isoform-specific regulation of igfbp expression by Gh.


Asunto(s)
Hormona del Crecimiento/farmacología , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Hígado/metabolismo , Animales , Ayuno/fisiología , Hipofisectomía , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Isoformas de Proteínas , ARN Mensajero/genética , Radioinmunoensayo , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tilapia/metabolismo
15.
Gen Comp Endocrinol ; 206: 146-54, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-25088575

RESUMEN

Euryhaline teleosts are faced with significant challenges during changes in salinity. Osmoregulatory responses to salinity changes are mediated through the neuroendocrine system which directs osmoregulatory tissues to modulate ion transport. Prolactin (PRL) plays a major role in freshwater (FW) osmoregulation by promoting ion uptake in osmoregulatory tissues, including intestine. We measured mRNA expression of ion pumps, Na(+)/K(+)-ATPase α3-subunit (NKAα3) and vacuolar type H(+)-ATPase A-subunit (V-ATPase A-subunit); ion transporters/channels, Na(+)/K(+)/2Cl(-) co-transporter (NKCC2) and cystic fibrosis transmembrane conductance regulator (CFTR); and the two PRL receptors, PRLR1 and PRLR2 in eleven intestinal segments of Mozambique tilapia (Oreochromis mossambicus) acclimated to FW or seawater (SW). Gene expression levels of NKAα3, V-ATPase A-subunit, and NKCC2 were generally lower in middle segments of the intestine, whereas CFTR mRNA was most highly expressed in anterior intestine of FW-fish. In both FW- and SW-acclimated fish, PRLR1 was most highly expressed in the terminal segment of the intestine, whereas PRLR2 was generally most highly expressed in anterior intestinal segments. While NKCC2, NKAα3 and PRLR2 mRNA expression was higher in the intestinal segments of SW-acclimated fish, CFTR mRNA expression was higher in FW-fish; PRLR1 and V-ATPase A-subunit mRNA expression was similar between FW- and SW-acclimated fish. Next, we characterized the effects of hypophysectomy (Hx) and PRL replacement on the expression of intestinal transcripts. Hypophysectomy reduced both NKCC2 and CFTR expression in particular intestinal segments; however, only NKCC2 expression was restored by PRL replacement. Together, these findings describe how both acclimation salinity and PRL impact transcript levels of effectors of ion transport in tilapia intestine.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Mucosa Intestinal/metabolismo , Transporte Iónico/fisiología , Prolactina/farmacología , Receptores de Prolactina/genética , Salinidad , Tilapia/metabolismo , Aclimatación/fisiología , Animales , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Agua Dulce , Intestinos/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Prolactina/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Agua de Mar , ATPasa Intercambiadora de Sodio-Potasio/genética , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Miembro 1 de la Familia de Transportadores de Soluto 12/genética , Miembro 1 de la Familia de Transportadores de Soluto 12/metabolismo , Tilapia/crecimiento & desarrollo , ATPasas de Translocación de Protón Vacuolares/genética , ATPasas de Translocación de Protón Vacuolares/metabolismo , Equilibrio Hidroelectrolítico/genética
16.
Artículo en Inglés | MEDLINE | ID: mdl-25193178

RESUMEN

This study investigated the effects of two rearing salinities, and acute salinity transfer, on the energetic costs of osmoregulation and the expression of metabolic and osmoregulatory genes in the gill of Mozambique tilapia. Using automated, intermittent-flow respirometry, measured standard metabolic rates (SMRs) of tilapia reared in seawater (SW, 130 mg O2 kg⁻¹ h⁻¹) were greater than those reared in fresh water (FW, 103 mg O2 kg⁻¹ h⁻¹), when normalized to a common mass of 0.05 kg and at 25±1°C. Transfer from FW to 75% SW increased SMR within 18h, to levels similar to SW-reared fish, while transfer from SW to FW decreased SMR to levels similar to FW-reared fish. Branchial gene expression of Na⁺-K⁺-2Cl⁻ cotransporter (NKCC), an indicator of SW-type mitochondria-rich (MR) cells, was positively correlated with SMR, while Na⁺-Cl⁻ cotransporter (NCC), an indicator of FW-type MR cells, was negatively correlated. Principal Components Analysis also revealed that branchial expression of cytochrome c oxidase subunit IV (COX-IV), glycogen phosphorylase (GP), and a putative mitochondrial biogenesis regulator in fish, peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), were correlated with a higher SMR, plasma osmolality, and environmental salinity, while expression of glycogen synthase (GS), PGC-1ß, and nuclear respiratory factor 1 (NRF-1) had negative correlations. These results suggest that the energetic costs of osmoregulation are higher in SW than in FW, which may be related to the salinity-dependent differences in osmoregulatory mechanisms found in the gills of Mozambique tilapia.


Asunto(s)
Región Branquial/fisiología , Metabolismo Energético , Regulación del Desarrollo de la Expresión Génica , Osmorregulación , Estrés Fisiológico , Tilapia/fisiología , Animales , Acuicultura , Región Branquial/enzimología , Región Branquial/crecimiento & desarrollo , Complejo IV de Transporte de Electrones/genética , Complejo IV de Transporte de Electrones/metabolismo , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Agua Dulce , Branquias/enzimología , Branquias/crecimiento & desarrollo , Branquias/fisiología , Glucógeno Fosforilasa/genética , Glucógeno Fosforilasa/metabolismo , Masculino , Análisis de Componente Principal , Salinidad , Agua de Mar , Miembro 1 de la Familia de Transportadores de Soluto 12/genética , Miembro 1 de la Familia de Transportadores de Soluto 12/metabolismo , Miembro 3 de la Familia de Transportadores de Soluto 12/genética , Miembro 3 de la Familia de Transportadores de Soluto 12/metabolismo , Tilapia/crecimiento & desarrollo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
17.
Rehabilitation (Stuttg) ; 53(1): 38-42, 2014 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-24217884

RESUMEN

OBJECTIVE: There is a lack of positive predictors for long-term treatment of subjects with alcohol addiction. We analyzed the relation between motivation and other external variables of access to treatment as well as treatment outcome. METHOD: 434 persons with alcohol addiction, treated in 2004 in the Diakonie-Krankenhaus Harz (DHK), Elbingerode, as part of a long-term therapy, were followed-up one year after treatment. Access variables were defined and examined in relation to outcome variables with multiple linear and logistic regressions. RESULT: Ways of accessing treatment had no effect on later treatment outcome, while motiva­tion at the start of therapy was relevant: Patients with ambivalent motivation had the most negative outcome. CONCLUSION: Therapy motivation was the main predictor for the outcome of a long-term anti-addiction treatment. To improve the quality of the treatment system, interventions to strengthen motivation should be promoted.


Asunto(s)
Alcoholismo/diagnóstico , Alcoholismo/rehabilitación , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/normas , Cooperación del Paciente , Indicadores de Calidad de la Atención de Salud/normas , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Alemania , Humanos , Cuidados a Largo Plazo/métodos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Motivación , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
18.
Prenat Diagn ; 33(2): 173-8, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23280558

RESUMEN

OBJECTIVE: This study aims to assess the suitability of non-invasive prenatal RHD genotyping in non-immunized midtrimester pregnant women from a mixed ethnic population, to prevent unnecessary anti-D immunoglobulin prophylaxis and to identify RHD variants METHODS: Rhesus D-negative pregnant women were offered fetal RHD genotyping at 24 gestational weeks. A total of 284 samples were tested for RHD status using multiplex rt-PCR amplification of exons 5 and 7 of the RHD gene and exons 6 and 10 in selected cases. Women carrying RHD-negative fetuses were counseled about their option to avoid routine antenatal anti-D immunoglobulin administration. Diagnostic accuracy of RHD genotyping was compared with postnatal Rhesus D serotyping. RESULTS: A total of 184 positives (65%), 91 negatives (32%) and 7 cases (2.5%) compatibles with RHD variants were detected by RHD genotyping. No false negative results were found, and a single false positive was observed in a twin pregnancy. Genotyping was accepted when offered by 94% of women (284/302), and anti-D immunoglobulin was avoided in 95% (90/95) of RHD-negative fetuses. CONCLUSIONS: Non-invasive routine antenatal RHD genotyping at 24 weeks of pregnancy is a highly accurate method, resulting in the avoidance of 95% of unnecessary administrations of anti-D immunoglobulin, with no false negative results.


Asunto(s)
Técnicas de Genotipaje , Diagnóstico Prenatal , Sistema del Grupo Sanguíneo Rh-Hr/genética , Exones , Femenino , Sangre Fetal , Humanos , Recién Nacido , Masculino , Embarazo , Segundo Trimestre del Embarazo , Grupos Raciales/genética , España
19.
Gen Comp Endocrinol ; 192: 191-203, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23722201

RESUMEN

Prolactin (PRL) cells of the Mozambique tilapia, Oreochromis mossambicus, are osmoreceptors by virtue of their intrinsic osmosensitivity coupled with their ability to directly regulate hydromineral homeostasis through the actions of PRL. Layered upon this fundamental osmotic reflex is an array of endocrine control of PRL synthesis and secretion. Consistent with its role in fresh water (FW) osmoregulation, PRL release in tilapia increases as extracellular osmolality decreases. The hyposmotically-induced release of PRL can be enhanced or attenuated by a variety of hormones. Prolactin release has been shown to be stimulated by gonadotropin-releasing hormone (GnRH), 17-ß-estradiol (E2), testosterone (T), thyrotropin-releasing hormone (TRH), atrial natriuretic peptide (ANP), brain-natriuretic peptide (BNP), C-type natriuretic peptide (CNP), ventricular natriuretic peptide (VNP), PRL-releasing peptide (PrRP), angiotensin II (ANG II), leptin, insulin-like growth factors (IGFs), ghrelin, and inhibited by somatostatin (SS), urotensin-II (U-II), dopamine, cortisol, ouabain and vasoactive intestinal peptide (VIP). This review is aimed at providing an overview of the hypothalamic and extra-hypothalamic hormones that regulate PRL release in euryhaline Mozambique tilapia, particularly in the context on how they may modulate osmoreception, and mediate the multifunctional actions of PRL. Also considered are the signal transduction pathways through which these secretagogues regulate PRL cell function.


Asunto(s)
Prolactina/genética , Angiotensina II/metabolismo , Animales , Hormona Liberadora de Gonadotropina/metabolismo , Péptido Natriurético Tipo-C/metabolismo , Concentración Osmolar , Hormona Liberadora de Prolactina/metabolismo , Somatomedinas/metabolismo , Somatostatina/metabolismo , Tilapia
20.
Am J Physiol Regul Integr Comp Physiol ; 302(8): R1004-11, 2012 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-22378774

RESUMEN

In teleost fish, prolactin (PRL) is an important hormone for hyperosmoregulation. The release of PRL from the pituitary of Mozambique tilapia is stimulated by a decrease in extracellular osmolality. Previous studies have shown that hyposmotically induced PRL release is linked with cell volume changes, and that stretch-activated Ca(2+) channels are likely responsible for the initiation of the signal transduction for PRL release. In this study, we identified the stretch-activated Ca(2+) channel transient receptor potential vanilloid 4 (TRPV4) from the rostral pars distalis (RPD) of tilapia acclimated to freshwater (FW). TRPV4 transcripts were ubiquitously expressed in tilapia; the level of expression in RPDs of FW-acclimated fish was lower than that found in RPDs of seawater (SW)-acclimated fish. Immunohistochemical analysis of the pituitary revealed that TRPV4 is localized in the cell membrane of PRL cells of both FW and SW tilapia. A functional assay with CHO-K1 cells showed that tilapia TRPV4 responded to a decrease in extracellular osmolality, and that its function was suppressed by ruthenium red (RR) and activated by 4α-phorbol 12,13-didecanoate (4aPDD). Exposure of dissociated PRL cells from FW-acclimated tilapia to RR blocked hyposmolality induced PRL release. PRL release, on the other hand, was stimulated by 4aPDD. These results indicate that PRL release in response to physiologically relevant changes in extracellular osmolality is mediated by the osmotically sensitive TRPV4 cation channel.


Asunto(s)
Lactotrofos/metabolismo , Adenohipófisis/metabolismo , Prolactina/metabolismo , Canales Catiónicos TRPV/metabolismo , Tilapia/metabolismo , Equilibrio Hidroelectrolítico/fisiología , Aclimatación/fisiología , Animales
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