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2.
BMC Oral Health ; 22(1): 553, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36457084

RESUMO

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.


Assuntos
Fenda Labial , Fissura Palatina , Dente Supranumerário , Humanos , Fenda Labial/complicações , Fenda Labial/epidemiologia , Fissura Palatina/complicações , Fissura Palatina/epidemiologia , Estudos Retrospectivos , Dente Supranumerário/complicações , Dente Supranumerário/epidemiologia
3.
Vet J ; 286: 105865, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35817389

RESUMO

Current consensus defines mild-moderate equine asthma (mEA; previously inflammatory airway disease) by a hierarchy of indicators of lung pathology: cough, poor performance, increased tracheobronchial mucus, inflammatory bronchoalveolar lavage (BAL) cytology and pulmonary dysfunction. Exclusion criteria include fever, systemic disease, or increased resting respiratory effort. The aim of this review was to inform future research by identifying gaps, strengths and weaknesses in the current body of evidence supporting this consensus-proposed definition. Objectives were to critique evidence supporting the inclusion of each diagnostic indicator in the case definition, by summarising and evaluating evidence for its association with higher-level indicators of lung inflammation. Searches of three databases identified 2275 articles relating to mEA or its diagnostic indicators, from which 298 full-text articles were screened and 45 reviewed in full. Studies (n = 44) had been performed worldwide in clinics, hospitals, racetracks, yards or research herds, in 6092 horses. Studies were predominantly opportunistic observational (n = 13/44: 29.5%) or cross-sectional (n = 11/44; 25%). The median number of horses per study was 74. Where breed and use were reported most were Thoroughbreds (58.2%; 2730/4688) and racehorses (72.8%; n = 3960/5439). Domains rated as high risk of bias in almost 50% of articles were 'study power' and 'masking'. Heterogeneity in clinical and laboratory measures precluded meta-analysis. Evidence was more consistent for certain pairwise relationships (e.g., between cough and tracheobronchial mucus) than others (e.g., BAL cytology and lung function). Findings highlight the need for increased standardisation of diagnostic methods and reporting to facilitate future systematic review and meta-analysis.


Assuntos
Asma , Doenças dos Cavalos , Animais , Asma/diagnóstico , Asma/veterinária , Líquido da Lavagem Broncoalveolar , Consenso , Tosse/etiologia , Tosse/veterinária , Estudos Transversais , Doenças dos Cavalos/diagnóstico , Cavalos
6.
Rev. esp. anestesiol. reanim ; 66(8): 434-438, oct. 2019. ilus
Artigo em Espanhol | IBECS | ID: ibc-187560

RESUMO

La ecografía ha demostrado tener un papel determinante en el diagnóstico y pronóstico del tratamiento de los pacientes con politrauma. Describimos el caso de un hombre de 52 años politraumatizado y hemodinámicamente inestable. La evaluación ecográfica abdominal fue positiva para hemoperitoneo, por lo que se realizó una laparotomía exploratoria de urgencia. En el período intraoperatorio, se utilizó la ecografía pulmonar para excluir lesión pulmonar traumática. En el pulmón derecho, la ecografía pulmonar sugirió presencia de neumotórax y en el pulmón izquierdo, consolidación subpleural. Posteriormente se realizó una tomografía computarizada que confirmó los hallazgos ecográficos. Al cuarto día del ingreso se le realizó una corrección quirúrgica de fractura compleja izquierda de cadera, con un bloqueo cuadrado lumbar tipo 2 guiado por ecografía antes de la incisión quirúrgica. El procedimiento transcurrió sin incidentes y el paciente permaneció hemodinámicamente estable, sin signos indirectos de dolor. Este caso ilustra que el examen guiado por ecografía puede tener un papel crucial en el manejo de los pacientes politraumatizados. Fue una herramienta de diagnóstico fundamental en la evaluación inicial, así como en la gestión posterior en quirófano


Ultrasound has an important role in the diagnosis and prognosis of polytrauma patients. We describe a case of a 52-year-old man with hemodynamic instability and multiple injuries. Abdominal ultrasound evaluation was positive for hemoperitoneum, so an exploratory laparotomy was performed. During the intraoperative period, lung ultrasound was used to exclude traumatic lung injury. In the right lung, lung ultrasound suggested the presence of pneumothorax, and in the left a subpleural consolidation. Subsequently, a computed tomography was performed, confirming the sonographic findings. On the fourth admission day, he underwent surgical correction of a left hip fracture. A type 2 quadratus lumborum block (ultrasound-guided) was performed before surgical incision. The procedure was uneventful. The patient remained hemodynamically stable, without indirect signs of pain. This case shows that ultrasound-guided examination plays a crucial role in the management of polytrauma patients. It was a fundamental diagnostic tool in the initial evaluation, and was also used during surgery


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/diagnóstico por imagem , Anestesia por Condução/métodos , Ultrassonografia/métodos , Hemoperitônio/cirurgia , Plexo Lombossacral , Laparotomia/métodos , Tratamento de Emergência/métodos , Bloqueio Nervoso/métodos , Traumatismo Múltiplo/cirurgia
7.
Rev Esp Anestesiol Reanim (Engl Ed) ; 66(8): 434-438, 2019 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31466799

RESUMO

Ultrasound has an important role in the diagnosis and prognosis of polytrauma patients. We describe a case of a 52-year-old man with hemodynamic instability and multiple injuries. Abdominal ultrasound evaluation was positive for hemoperitoneum, so an exploratory laparotomy was performed. During the intraoperative period, lung ultrasound was used to exclude traumatic lung injury. In the right lung, lung ultrasound suggested the presence of pneumothorax, and in the left a subpleural consolidation. Subsequently, a computed tomography was performed, confirming the sonographic findings. On the fourth admission day, he underwent surgical correction of a left hip fracture. A type 2 quadratus lumborum block (ultrasound-guided) was performed before surgical incision. The procedure was uneventful. The patient remained hemodynamically stable, without indirect signs of pain. This case shows that ultrasound-guided examination plays a crucial role in the management of polytrauma patients. It was a fundamental diagnostic tool in the initial evaluation, and was also used during surgery.


Assuntos
Anestesiologia/métodos , Traumatismo Múltiplo/diagnóstico por imagem , Ultrassonografia/métodos , Anestesiologistas , Avaliação Sonográfica Focada no Trauma , Hemoperitônio/diagnóstico por imagem , Hemoperitônio/etiologia , Hemoperitônio/cirurgia , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/etiologia , Fraturas do Quadril/cirurgia , Humanos , Laparotomia , Fígado/lesões , Fígado/cirurgia , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/cirurgia , Bloqueio Nervoso , Pneumotórax/diagnóstico por imagem , Pneumotórax/etiologia , Sistemas Automatizados de Assistência Junto ao Leito , Cuidados Pré-Operatórios/métodos , Prática Profissional , Baço/diagnóstico por imagem , Baço/lesões , Baço/cirurgia , Esplenectomia , Tomografia Computadorizada por Raios X , Ultrassonografia de Intervenção
8.
Soft Matter ; 15(5): 956-962, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30652170

RESUMO

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.

9.
RSC Adv ; 9(8): 4415-4421, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35520196

RESUMO

Theoretical calculations are performed using the Vienna Ab-initio simulation package (VASP) to understand the mechanisms that control the adsorption of Ampyra drug on the different crystallographic planes of ß-cristobalite: the hydroxylated (111) and (100) surfaces. The Ampyra-silica interaction is most favored on the (100) surface where the entire ring of the molecule interacts with the surface while on the (111) face, lesser exchange and fewer non-polar atoms are involved. Calculations show that the interactions mainly occur at the interface between the Ampyra and the closest silanol groups, according to the formation of the H-bonding interactions. The results indicate that the H-bonds have an important influence on the adsorption of the Ampyra. In consequence, adsorption on the (111) surface is observed to a lesser extent than on the (100) surface according the smaller hydroxyl density.

10.
Eur Phys J E Soft Matter ; 41(9): 107, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30219930

RESUMO

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.


Assuntos
Alumínio/química , Antineoplásicos/química , Carvão Vegetal/química , Fluoruracila/química , Teoria Quântica , Adsorção , Modelos Moleculares , Conformação Molecular
11.
Artigo em Inglês | MEDLINE | ID: mdl-30186233

RESUMO

We assessed if leptin, a cytokine hormone known to enhance energy expenditure by promoting lipid and carbohydrate catabolism in response to physiologic stress, might directly regulate cellular glycolysis. A transcriptomic analysis of prolactin cells in the tilapia (Oreochromis mossambicus) pituitary rostral pars distalis (RPD) revealed that recombinant leptin (rtLep) differentially regulates 1,995 genes, in vitro. Machine learning algorithms and clustering analyses show leptin influences numerous cellular gene networks including metabolism; protein processing, transport, and metabolism; cell cycle and the hypoxia response. Leptin stimulates transcript abundance of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (gapdh) in a covariate manner to the hypoxic stress gene network. Orthogonal tests confirm that rtLepA dose-dependently increases gapdh gene expression in the RPD along with transcript abundance of 6-phosphofructo-1-kinase (pfk1), the rate limiting glycolytic enzyme. Functional testing demonstrated that leptin stimulates PFK activity and glycolytic output, while Stattic (a STAT3 blocker) was sufficient to suppress these responses, indicating leptin stimulates glycolysis through a STAT3-dependent mechanism. Leptin also stimulated pfk1 gene expression and lactate production in primary hepatocyte incubations in a similar manner to those shown for the pituitary RPD. This work characterizes a critical metabolic action of leptin to directly stimulate glycolysis across tissue types in a teleost model system, and suggest that leptin may promote energy expenditure, in part, by stimulating glycolysis. These data in a teleost fish, suggest that one of leptin's ancient, highly-conserved functions among vertebrates may be stimulation of glycolysis to facilitate the energetic needs associated with various stressors.

12.
Gen Comp Endocrinol ; 257: 168-176, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28652133

RESUMO

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.


Assuntos
Ciclídeos , Prolactina/metabolismo , Receptores da Prolactina/metabolismo , Animais , Concentração Osmolar , Osmorregulação , Salinidade
13.
J Mol Endocrinol ; 59(4): 391-402, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28974537

RESUMO

Teleosts inhabiting fresh water (FW) depend upon ion-absorptive ionocytes to counteract diffusive ion losses to the external environment. A Clc Cl- channel family member, Clc-2c, was identified as a conduit for basolateral Cl- transport by Na+/Cl- cotransporter 2 (Ncc2)-expressing ionocytes in stenohaline zebrafish (Danio rerio). It is unresolved whether Clc-2c/clc-2c is expressed in euryhaline species and how extrinsic and/or intrinsic factors modulate branchial clc-2c mRNA. Here, we investigated whether environmental salinity, prolactin (Prl) and osmotic conditions modulate clc-2c expression in euryhaline Mozambique tilapia (Oreochromis mossambicus). Branchial clc-2c and ncc2 mRNAs were enhanced in tilapia transferred from seawater (SW) to FW, whereas both mRNAs were attenuated upon transfer from FW to SW. Next, we injected hypophysectomized tilapia with ovine prolactin (oPrl) and observed a marked increase in clc-2c from saline-injected controls. To determine whether Prl regulates clc-2c in a gill-autonomous fashion, we incubated gill filaments in the presence of homologous tilapia Prls (tPrl177 and tPrl188). By 24 h, tPrl188 stimulated clc-2c expression ~5-fold from controls. Finally, filaments incubated in media ranging from 280 to 450 mosmol/kg for 3 and 6 h revealed that extracellular osmolality exerts a local effect on clc-2c expression; clc-2c was diminished by hyperosmotic conditions (450 mosmol/kg) compared with isosmotic controls (330 mosmol/kg). Our collective results suggest that hormonal and osmotic control of branchial clc-2c contributes to the FW adaptability of Mozambique tilapia. Moreover, we identify for the first time a regulatory link between Prl and a Clc Cl- channel in a vertebrate.


Assuntos
Canais de Cloreto/genética , Canais de Cloreto/metabolismo , Brânquias/fisiologia , Concentração Osmolar , Prolactina/metabolismo , Salinidade , Tilápia/fisiologia , Animais , Canais de Cloro CLC-2 , Regulação da Expressão Gênica , Masculino , Especificidade de Órgãos/genética , Isoformas de Proteínas
14.
Gen Comp Endocrinol ; 240: 227-237, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27449341

RESUMO

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.


Assuntos
Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/metabolismo , Fígado/metabolismo , Receptores da Somatotropina/metabolismo , Tilápia/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Jejum , Comportamento Alimentar/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hipofisectomia , Masculino , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , RNA Mensageiro/genética , Receptores da Somatotropina/genética
15.
J Endocrinol ; 230(3): 325-37, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27402066

RESUMO

Aquaporins (Aqps) are expressed within key osmoregulatory tissues where they mediate the movement of water and selected solutes across cell membranes. We leveraged the functional plasticity of Mozambique tilapia (Oreochromis mossambicus) gill epithelium to examine how Aqp3, an aquaglyceroporin, is regulated in response to osmoregulatory demands. Particular attention was paid to the actions of critical osmoregulatory hormones, namely, prolactin (Prl), growth hormone and cortisol. Branchial aqp3 mRNA levels were modulated following changes in environmental salinity, with enhanced aqp3 mRNA expression upon transfer from seawater to freshwater (FW). Accordingly, extensive Aqp3 immunoreactivity was localized to cell membranes of branchial epithelium in FW-acclimated animals. Upon transferring hypophysectomized tilapia to FW, we identified that a pituitary factor(s) is required for Aqp3 expression in FW. Replacement with ovine Prl (oPrl) was sufficient to stimulate Aqp3 expression in hypophysectomized animals held in FW, an effect blocked by coinjection with cortisol. Both oPrl and native tilapia Prls (tPrl177 and tPrl188) stimulated aqp3 in incubated gill filaments in a concentration-related manner. Consistent with in vivo responses, coincubation with cortisol blocked oPrl-stimulated aqp3 expression in vitro Our data indicate that Prl and cortisol act directly upon branchial epithelium to regulate Aqp3 in tilapia. Thus, within the context of the diverse actions of Prl on hydromineral balance in vertebrates, we define a new role for Prl as a regulator of Aqp expression.


Assuntos
Aquaporina 3/metabolismo , Proteínas de Peixes/metabolismo , Brânquias/metabolismo , Hidrocortisona/farmacologia , Prolactina/farmacologia , Tilápia/metabolismo , Animais , Animais Geneticamente Modificados , Aquaporina 3/genética , Proteínas de Peixes/genética , Água Doce , Brânquias/efeitos dos fármacos , RNA Mensageiro/genética , Água do Mar , Ovinos , Tilápia/genética , Equilíbrio Hidroeletrolítico/efeitos dos fármacos
16.
Endocrinology ; 157(9): 3505-16, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27379370

RESUMO

Prolactin (PRL) is a vertebrate hormone with diverse actions in osmoregulation, metabolism, reproduction, and in growth and development. Osmoregulation is fundamental to maintaining the functional structure of the macromolecules that conduct the business of life. In teleost fish, PRL plays a critical role in osmoregulation in fresh water. Appropriately, PRL cells of the tilapia are directly osmosensitive, with PRL secretion increasing as extracellular osmolality falls. Using a model system that employs dispersed PRL cells from the euryhaline teleost fish, Oreochromis mossambicus, we investigated the autocrine regulation of PRL cell function. Unknown was whether these PRL cells might also be sensitive to autocrine feedback and whether possible autocrine regulation might interact with the well-established regulation by physiologically relevant changes in extracellular osmolality. In the cell-perfusion system, ovine PRL and two isoforms of tilapia PRL (tPRL), tPRL177 and tPRL188, stimulated the release of tPRLs from the dispersed PRL cells. These effects were significant within 5-10 minutes and lasted the entire course of exposure, ceasing within 5-10 minutes of removal of tested PRLs from the perifusion medium. The magnitude of response varied between tPRL177 and tPRL188 and was modulated by extracellular osmolality. On the other hand, the gene expression of tPRLs was mainly unchanged or suppressed by static incubations of PRL cells with added PRLs. By demonstrating the regulatory complexity driven by positive autocrine feedback and its interaction with osmotic stimuli, these findings expand upon the knowledge that pituitary PRL cells are regulated complexly through multiple factors and interactions.


Assuntos
Comunicação Autócrina , Retroalimentação Fisiológica , Lactotrofos/metabolismo , Osmorregulação , Prolactina/metabolismo , Animais , Feminino , Masculino , Tilápia
17.
Artigo em Inglês | MEDLINE | ID: mdl-27210417

RESUMO

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.


Assuntos
Claudinas/genética , Proteínas de Peixes/genética , Brânquias/efeitos dos fármacos , Hidrocortisona/farmacologia , Prolactina/farmacologia , Tilápia/genética , Animais , Água Doce , Regulação da Expressão Gênica/efeitos dos fármacos , Brânquias/metabolismo , Hipofisectomia , Técnicas In Vitro , Isoformas de Proteínas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Salinidade , Água do Mar , Transcriptoma/efeitos dos fármacos
18.
Artigo em Inglês | MEDLINE | ID: mdl-27032617

RESUMO

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.


Assuntos
Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Tilápia/fisiologia , Ração Animal , Animais , Aquicultura , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica , Hormônio do Crescimento/genética , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like II/genética , Fígado/fisiologia , Músculos/fisiologia , Hipófise/metabolismo , Receptores da Somatotropina/genética , Salinidade , Tilápia/crescimento & desenvolvimento , Tilápia/metabolismo
19.
Am J Physiol Regul Integr Comp Physiol ; 309(10): R1251-63, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26377558

RESUMO

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.


Assuntos
Transporte de Íons/fisiologia , Concentração Osmolar , Prolactina/farmacologia , Simportadores de Cloreto de Sódio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Tilápia/fisiologia , Animais , Matriz Extracelular , Regulação da Expressão Gênica/fisiologia , Brânquias , Masculino , Receptores da Prolactina/genética , Receptores da Prolactina/metabolismo , Simportadores de Cloreto de Sódio/genética , Regulação para Cima
20.
Gen Comp Endocrinol ; 224: 216-27, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26320855

RESUMO

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.


Assuntos
Evolução Biológica , Peixe Elétrico/metabolismo , Evolução Molecular , Filogenia , Hipófise/metabolismo , Prolactina/metabolismo , Sequência de Aminoácidos , Animais , Clonagem Molecular , Peixe Elétrico/crescimento & desenvolvimento , Hibridização In Situ , Dados de Sequência Molecular , Hipófise/citologia , Homologia de Sequência de Aminoácidos , Distribuição Tecidual
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