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1.
Artigo em Inglês | MEDLINE | ID: mdl-38876439

RESUMO

External and internal factors are involved in controlling the growth of fishes. However, little is known about the mechanisms by which external factors trigger stimulus signals. This study explored the physiological roles of melatonin in the transcription of growth-related genes in the brain and liver of Chrysiptera cyanea, a tropical damselfish with long-day preference. In brain samples of this species collected at 4-h intervals, the transcript levels of arylalkylamine N-acetyltransferase2 (aanat2), the rate-limiting enzyme of melatonin synthesis, and growth hormone (gh) peaked at 20:00 and 00:00, respectively. Concomitantly, the transcript levels of insulin-like growth factors (igf1 and igf2) in the brain and liver were upregulated during the scotophase. Levels of iodothyronine deiodinases (dio2 and dio3), enzymes that convert thyroxine (T4) to triiodothyronine (T3) and reverse T3, respectively, increased in the brain (dio2 and dio3) and liver (dio2) during the photophase, whereas dio3 levels in the liver showed the opposite trend. Fish reared in melatonin-containing water exhibited significant increases in the transcription levels of gh and igf1 in the brain and igf1 in the liver, suggesting that growth in this fish is positively regulated by the GH/IGF pathway on a daily basis. Melatonin treatment also stimulated the transcript levels of dio2 and dio3 in the liver, but not in the brain. Fish consuming pellets containing T3, but not T4, showed significant increases in gh and igf1 in the brain and igf1 and igf2 in the liver, suggesting that the intercellular actions of the TH/IGF pathway have an impact on growth on a daily basis. In summary, IGF synthesis and action in the brain and liver undergo dual regulation by distinct hormone networks, which may also be affected by daily, seasonal, or nutritional factors.

2.
Artigo em Inglês | MEDLINE | ID: mdl-37269939

RESUMO

Salinity, a determining factor in aquatic environments, influences fish growth. Here, we evaluated the effect of salinity on osmoregulation and growth performance in juveniles of the Malabar grouper, Epinephelus malabaricus, a species of high commercial value in Asian markets; we also identified the salinity that maximized this species' growth rate. Fish were reared at 26 °C and under a 14:10 h photoperiod with a salinity of 5 psu, 11 psu, 22 psu, or 34 psu for 8 weeks. Change in salinity had minimal impact on the plasma Na+ and glucose concentrations, although the Na+/K+-ATPase (nkaα and nkaß) transcript levels in the gills were significantly lower among fish reared at 11 psu salinity. Concomitantly, oxygen consumption was low in fish reared at 11 psu salinity. The feed conversion ratio (FCR) was lower in fish reared at 5 psu and 11 psu salinities than at 22 psu and 34 psu salinities. However, the specific growth rate (SGR) was higher in fish reared at 11 psu salinity. These results suggest that rearing fish at 11 psu salinity would decrease energy consumption for respiration and improve food-conversion efficiency. Among fish reared at 11 psu salinity, the transcript levels of growth hormone (gh) in the pituitary, as well as its receptor (ghr) and insulin-like growth factor I (igf-1) in the liver, were upregulated; these findings suggested stimulation of the growth axis at low salinity. In contrast, there were minimal differences in the transcript levels of neuropeptide Y (npy) and pro-opiomelanocortin (pomc) in the brains of fish reared at any salinity, suggesting that salinity does not affect appetite. Therefore, growth performance is higher in fish reared at 11 psu salinity because of activation of the GH-IGF system, but not appetite, in Malabar grouper juveniles.


Assuntos
Bass , Animais , Bass/metabolismo , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Osmorregulação , Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo , Equilíbrio Hidroeletrolítico , Salinidade
3.
J Appl Clin Med Phys ; 24(3): e13849, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36443959

RESUMO

We have proposed a method for patient-specific dose-volume histogram (DVH) verification using a 40-ms high-sampling-rate log file (HLF) available in an Elekta linac. Ten prostate volumetric-modulated arc therapy plans were randomly selected, and systematic leaf position errors of ±0.2, ±0.4, or ±0.8 mm were added to the 10 plans, thereby producing a total of 70 plans. An RTP file was created by interpolating each leaf position in the HLF to obtain values at each control point, which is subsequently exported to a treatment planning system. The isocenter dose calculated by the HLF-based plan to a phantom (Delta4 Phantom+) was compared to that measured by the diode in the phantom in order to evaluate the accuracy of the HLF-based dose calculation. The D95 of the planning target volume (PTV) was also compared between the HLF-based plans and the original plans with the systematic leaf position errors, the latter being referred to as theory-based plans. Sensitivities of the DVH parameters in the target, the rectum, and the bladder were also calculated with the varied systematic leaf position errors. The relative differences in the isocenter doses between the HLF-based calculations and the measurements among the 70 plans were 0.21% ± 0.67% (SD). The maximum relative differences in PTV D95 between the HLF-based and the theory-based plans among the 70 cases were 0.11%. The patient-specific DVH verification method detected a change in the target DVH parameters of less than 1% when the systematic leaf position error was ±0.2 mm. It is therefore suggested that the proposed DVH verification method may simplify patient-specific dose quality assurance procedures without compromising accuracy and sensitivity.


Assuntos
Radioterapia de Intensidade Modulada , Software , Masculino , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Garantia da Qualidade dos Cuidados de Saúde , Dosagem Radioterapêutica , Imagens de Fantasmas , Radioterapia de Intensidade Modulada/métodos
4.
Zoolog Sci ; 39(6): 570-580, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36495492

RESUMO

Synchronous spawning is a striking feature of coral. Although it is important for reproductive success, corals reallocate energy for reproduction to growth when they are damaged by external stimuli. To assess the transcriptome before and after spawning in the scleractinian coral Acropora tenuis, we tagged three colonies (one bleached and two unbleached) in the field around Sesoko Island (Okinawa, Japan) in November 2016, sampled them monthly from May to July 2017, and performed RNA sequencing (RNA-Seq) analysis. Histological analysis revealed that the previously bleached colony possessed gametes in June, by which time the other two colonies had already spawned. In RNA-Seq analyses, multi-dimensional scaling based on gene expression similarity among the samples reflected the differences between colonies and between months except for the sample of a non-spawned colony in May, which was similar to the samples in June. The similarity of the non-spawned colony sample in May to the samples in June was also shown in hierarchical clustering based on the expression patterns of the genes that were differentially expressed between months in the spawned colonies. These results suggest that non-spawning was already decided in May, and that the physiological condition in a non-spawned colony in May was advanced to June. RNA-Seq analysis also showed that genes related to gametogenesis and those related to apoptosis were upregulated before and after spawning, respectively.


Assuntos
Antozoários , Animais , Antozoários/genética , Estações do Ano , Gametogênese/genética , Reprodução/fisiologia , Perfilação da Expressão Gênica
5.
J Appl Clin Med Phys ; 23(3): e13493, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35077004

RESUMO

The Catalyst™ HD (C-RAD Positioning AB, Uppsala, Sweden) is surface-guided radiotherapy (SGRT) equipment that adopts a deformable model. The challenge in applying the SGRT system is accurately correcting the setup error using a deformable model when the body of the patient is deformed. This study evaluated the effect of breast deformation on the accuracy of the setup correction of the SGRT system. Physical breast phantoms were used to investigate the relationship between the mean deviation setup error obtained from the SGRT system and the breast deformation. Physical breast phantoms were used to simulate extension and shrinkage deformation (-30 to 30 mm) by changing breast pieces. Three-dimensional (3D) Slicer software was used to evaluate the deformation. The maximum deformations in X, Y, and Z directions were obtained as the differences between the original and deformed breasts. We collected the mean deviation setup error from the SGRT system by replacing the original breast part with the deformed breast part. The mean absolute difference of lateral, longitudinal, vertical, pitch, roll, and yaw, between the rigid and deformable registrations was 2.4 ± 1.7 mm, 1.3 ± 1.2 mm, 6.4 ± 5.2 mm, 2.5° ± 2.5°, 2.2° ± 2.4°, and 1.0° ± 1.0°, respectively. Deformation in the Y direction had the best correlation with the mean deviation translation error (R = 0.949) and rotation error (R = 0.832). As the magnitude of breast deformation increased, both mean deviation setup errors increased, and there was greater error in translation than in rotation. Large deformation of the breast surface affects the setup correction. Deformation in the Y direction most affects translation and rotation errors.


Assuntos
Braquiterapia , Radioterapia Guiada por Imagem , Braquiterapia/métodos , Humanos , Posicionamento do Paciente/métodos , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador/métodos , Erros de Configuração em Radioterapia/prevenção & controle , Radioterapia Guiada por Imagem/métodos
6.
Fish Physiol Biochem ; 48(1): 253-262, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35099686

RESUMO

Photoperiod plays a role in controlling the initiation and termination of reproduction in fish. Melatonin is an internal transducer of environmental photoperiod and is involved in regulating reproduction. The present study aimed to examine how melatonin impacts the transcript levels of kisspeptin (kiss1 and kiss2), gonadotropin-releasing hormones (gnrh1), and the ß-subunit of gonadotropins (fshß and lhß) in the brain of the sapphire devil, a tropical damselfish with long photoperiod preference. Feeding mature females with melatonin-containing pellets inhibited increases in the transcript levels of kiss1, gnrh1, and lhß within 3 h. Continuous melatonin treatment for 1 week resulted in oocyte regression and downregulation of kiss2, gnrh1, fshß, and lhß. When the transcript levels of kiss1 and gnrh1 were measured at 4-h intervals in the brain of sapphire devil, a day-high/night-low fluctuation was observed. The hypothalamic-pituitary-gonadal (HPG) axis may be influenced by melatonin, exerting a negative effect at night because the transcript levels of aralkylamine N-acetyltransferase (aanat2) increased during the scotophase. The expression of aanat2 was higher under short-day than long-day conditions, suggesting that there is a seasonal change in melatonin levels at night. It was concluded that change in photoperiod becomes a key factor for controlling the hormone synthesis in the HPG axis through melatonin.


Assuntos
Melatonina , Perciformes , Reprodução , Animais , Feminino , Subunidade beta do Hormônio Folículoestimulante , Hormônio Liberador de Gonadotropina , Kisspeptinas/genética , Hormônio Luteinizante Subunidade beta , Melatonina/farmacologia , Perciformes/fisiologia
7.
Zoolog Sci ; 38(6): 558-564, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34854287

RESUMO

This study investigated ovarian development and larval release in the hermit crab Clibanarius eurysternus, which inhabits the upper intertidal zone on Okinawa, Japan. Adult females were collected monthly and had a high gonadosomatic index (GSI) from May to October. Oocytes at vitellogenic stages were observed from May to October. Some females had post-ovulatory follicles in the ovary and embryos on the abdomen (ovigerous females) in June and August, suggesting active ovarian development and larval release during these months (breeding season). When adult females were collected weekly according to the lunar cycle, a high GSI with oocytes at the tertiary yolk globule stage in the ovaries was maintained in all lunar phases. Since post-ovulated follicles were seen in ovaries collected around the last quarter and new moons, darkness at night is needed for spawning. Ovigerous females exposed to stepwise changes in hydrostatic pressure exhibited significantly higher synchrony between larval release and high pressure at night from the last quarter moon to the new moon, suggesting the importance of the tidal amplitude cycle in larval release under non-moonlight conditions. We concluded that the continuity of synchronous spawning and larval release of C. eurysternus are repeated under darkness and high tide at night during the breeding season.


Assuntos
Anomuros , Animais , Feminino , Japão , Larva , Ovário , Ovulação
8.
Artigo em Inglês | MEDLINE | ID: mdl-33486078

RESUMO

Most broadcast spawner corals have a vitellogenic phase that lasts at least 6 months. It is established that estrogen regulates vitellogenin synthesis in vertebrates. Although some research have been conducted on the physiological role of sex steroids in corals, little is known about their involvement in oocyte development. This study aimed to detect steroid hormones - progesterone, testosterone, and estradiol-17ß (E2) - in Acropora tenuis and study the relationships between vitellogenesis/vitellogenin synthesis and these steroids. This study also investigated the effect of E2 on vitellogenin synthesis in corals and identified steroidogenic enzymes in A. tenuis genome. Branches from tagged coral colonies were collected monthly from March to November. Histological observations showed that oocytes were vitellogenic from March to May (Stage IV and V), but not in June, and that gonads were occupied by immature oocytes in September (Stage I). Real-time qPCR revealed that vitellogenin (vg1 and vg2) transcript levels in coral branches were high in April and May, implying that corals actively underwent vitellogenesis during these months, and spawned before June. Liquid chromatography-mass spectrometry revealed that E2 could be detected in coral branches in March, April, and May, but not in June, whereas testosterone and progesterone did not fluctuate much in the same months. Immersing branches in E2-containing seawater failed to increase vitellogenin transcript levels. The results indicate that E2 is involved in oogenesis but does not positively regulate vitellogenin synthesis. Steroidogenic enzymes (except CYP19A) were identified in A. tenuis, suggesting that corals may endogenously synthesize progestogens and androgens from cholesterol.


Assuntos
Antozoários/metabolismo , Estradiol/fisiologia , Vitelogeninas/biossíntese , Animais , Cromatografia Líquida/métodos , Clonagem Molecular , Estradiol/metabolismo , Espectrometria de Massas/métodos , Oócitos/citologia , Oogênese/fisiologia , Progesterona/metabolismo , RNA Mensageiro/genética , Testosterona/metabolismo , Vitelogeninas/genética
9.
J Appl Clin Med Phys ; 22(6): 262-267, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34048143

RESUMO

This study aims to investigate the influence of the phantom position on weighted computed tomography dose index (CTDIw ) in cone beam computed tomography (CBCT) when assuming breast irradiation. Computed tomography dose index (CTDI) was measured by the x-ray volume imaging of CBCT using parameters for image-guided radiation therapy (IGRT) in right breast irradiation. The measurement points of CTDI ranged from 0 (center) to 16 cm in the right-left (RL) direction, and from 0 (center) to 7.5 cm in the anterior-posterior (AP) direction, which assumed right breast irradiation. A nonuniform change exists in the relative value of CTDIw when the phantom deviated from the isocenter of CBCT. The CTDIw was ~30% lower compared with the value at the isocenter of CBCT when the phantom deviated 7.5 and 16 cm at the AP and RL directions, respectively. This study confirmed the influence of the phantom position on the CTDI values of CBCT. The CTDI measured at the isocenter of CBCT overestimates that measured at the irradiation center of the breast.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Radioterapia Guiada por Imagem , Humanos , Imagens de Fantasmas , Dosagem Radioterapêutica , Raios X
10.
J Appl Clin Med Phys ; 22(2): 58-68, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33369014

RESUMO

The Catalyst HD (C-RAD Positioning AB, Uppsala, Sweden) optical surface imaging (OSI) system is able to manage interfractional patient positioning, intrafractional motion monitoring, and non-contact respiratory gating without x-ray exposure for radiation therapy. In recent years, a novel high-precision surface registration algorithm for stereotactic radiosurgery (SRS algorithm) has been released. This study aimed to evaluate the technical performance of the OSI system using rigid phantoms, by comparing the conventional and SRS algorithms. To determine the system's technical performance, isocenter displacements were calculated by surface image registration via the OSI system using head, thorax, and pelvis rigid phantoms. The reproducibility of positioning was evaluated by the mean value calculated by repeating the registration 10 times, without moving each phantom. The accuracy of positioning was evaluated by the mean value of the residual error, where the 10 offset values given to each phantom were subtracted from the isocenter displacement values. The stability of motion monitoring was evaluated by measuring isocenter drift during 20 min and averaging it over 10 measurements. For the head phantom, all tests were compared with the mask types and algorithms. As a result, for all sites and both algorithms, the reproducibility, accuracy, and stability for translation and rotation were <0.1 mm and <0.1°, <1.0 mm and <1.0°, and <0.1 mm and <0.1°, respectively. In particular, the SRS algorithm had a small absolute error and standard deviation of calculated isocenter displacement, and a significantly higher reproducibility and accuracy than the conventional algorithm (P < 0.01). There was no difference in the stability between the algorithms (P = 0.0280). The SRS algorithm was found to be suitable for the treatment of rigid body sites with less deformation and small area, such as the head and face.


Assuntos
Radiocirurgia , Algoritmos , Humanos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Suécia
11.
J Appl Clin Med Phys ; 22(1): 76-91, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33270985

RESUMO

PURPOSE: To investigate the effect of an integral quality monitor (IQM; iRT Systems GmbH, Koblenz, Germany) on 4, 6, 10, and 6-MV flattening filter-free (FFF) photon beams. METHODS: We assessed surface dose, PDD20,10 , TPR20,10 , PDD curves, inline and crossline profiles, transmission factor, and output factor with and without the IQM. PDD, transmission factor, and output factor were measured for square fields of 3, 5, 10, 15, 20, 25, and 30 cm and profiles were performed for square fields of 3, 5, 10, 20, and 30 cm at 5-, 10-, and 30-cm depth. RESULTS: The differences in surface dose of all energies for square fields of 3, 5, 10, 15, 20, and 25 cm were within 3.7% whereas for a square field of 30 cm, they were 4.6%, 6.8%, 6.7%, and 8.7% for 4-MV, 6-MV, 6-MV-FFF, and 10-MV, respectively. Differences in PDD20,10 , TPR20,10 , PDD, profiles, and output factors were within ±1%. Local and global gamma values (2%/2 mm) were below 1 for PDD beyond dmax and inline/crossline profiles in the central beam region, respectively. The gamma passing rates (10% threshold) for PDD curves and profiles were above 95% at 2%/2 mm. The transmission factors for 4-MV, 6-MV, 6-MV-FFF, and 10-MV for field sizes from 3 × 3 to 30 × 30 cm2 were 0.926-0.933, 0.937-0.941, 0.937-0.939, and 0.949-0.953, respectively. CONCLUSIONS: The influence of the IQM on the beam quality (in particular 4-MV X-ray has not verified before) was tested and introduced a slight beam perturbation at the surface and build-up region and the edge of the crossline/inline profiles. To use IQM in pre- and intra-treatment quality assurance, a tray factor should be put into treatment planning systems for the dose calculation for the 4-, 6-, 10-, and 6-MV flattening filter-free photon beams to compensate the beam attenuation of the IQM detector.


Assuntos
Aceleradores de Partículas , Radiometria , Humanos , Fótons
12.
Gen Comp Endocrinol ; 295: 113479, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32246963

RESUMO

Food availability is a permissive determinant that drives gonadal activity in fish. The present study aimed to clarify the interactions between reproductive and nutritive statuses in the sapphire devil (Chrysiptera cyanea), a tropical damselfish with a long-day preference for reproduction. Insulin-like growth factor 3 (IGF3), a novel IGF that likely plays a role in gonadal maturation, was closely monitored in the sapphire devil. The cDNA of sapphire devil igf3 had an open reading frame of 443 base pairs (146 amino acid residues). Phylogenetic analyses revealed that sapphire devil IGF3 was clustered within the teleost IGF3 family. The transcript levels of sapphire devil igf3 increased in the brain, liver, and ovary of the fish during the late vitellogenic phase, suggesting that it plays a role in reproduction. Immersion of the fish in seawater containing estradiol-17ß suppressed transcript levels of sapphire devil igf3 in the liver, but not in the brain, suggesting that intensive protein synthesis in relation to vitellogenesis negatively impacts somatic metabolism in this tissue. When fish were reared with high or low food under conditions of photoperiod (LD = 14:10) and temperature (at 25-28 °C) during the non-reproductive season, ovarian development was induced in high-food fish. Furthermore, prior to ovarian development in the high-food fish, the transcript levels of sapphire devil igf3 increased in the brain, liver, and ovary. These results indicated crosstalk between the reproductive and growth networks and suggested that a metabolic shift, from growth mode to reproductive mode, occurs in peripheral tissues when nutritive status is improved under suitable conditions of photoperiod and water temperature.


Assuntos
Alimentos , Perciformes/genética , Perciformes/fisiologia , Reprodução/genética , Estações do Ano , Somatomedinas/genética , Sequência de Aminoácidos , Animais , Clonagem Molecular , Estradiol/farmacologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Ovário/citologia , Ovário/efeitos dos fármacos , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodução/efeitos dos fármacos , Somatomedinas/química , Somatomedinas/metabolismo , Distribuição Tecidual
13.
Gen Comp Endocrinol ; 285: 113264, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31469997

RESUMO

Thyroid hormone (TH) is involved in regulating the reproduction of vertebrates. Its physiological action in the target tissues is due to the conversion of TH by iodothyronine deiodinases. In this study, we aimed to clone and characterize type 2 (sdDio2) and type 3 (sdDio3) of the sapphire devil Chrysiptera cyanea, a tropical damselfish that undergoes active reproduction under long-day conditions, and to study the involvement of THs in the ovarian development of this species. When the cDNAs of sdDio2 and sdDio3 were partially cloned, they had deduced amino acid sequences of lengths 271 and 267, respectively, both of which were characterized by one selenocysteine residue. Real-time quantitative PCR (qPCR) revealed that both genes are highly expressed in the whole brain, and sdDio2 and sdDio3 are highly transcribed in the liver and ovary, respectively. In situ hybridization analyses showed positive signals of sdDio2 and sdDio3 transcripts in the hypothalamic area of the brain. Little change in mRNA abundance of sdDio2 and sdDio3 in the brain was observed during the vitellogenic phases. It is assumed that simultaneous activation and inactivation of THs occur in this area because oral administration of triiodothyronine (T3), but not of thyroxine (T4), upregulated mRNA abundance of both genes in the brain. The transcript levels of sdDio2 in the liver and sdDio3 in the ovary increased as vitellogenesis progressed, suggesting that, through the metabolism of THs, sdDio2 and sdDio3 play a role in vitellogenin synthesis in the liver and yolk accumulation/E2 synthesis in the ovary. Taken together, these results suggest that iodothyronine deiodinases act as a driver for vitellogenesis in tropical damselfish by conversion of THs in certain peripheral tissues.


Assuntos
Perfilação da Expressão Gênica , Iodeto Peroxidase/genética , Perciformes/genética , Clima Tropical , Vitelogênese/genética , Animais , Feminino , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Iodeto Peroxidase/metabolismo , Ovário/efeitos dos fármacos , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Perciformes/metabolismo , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Hormônios Tireóideos/administração & dosagem , Hormônios Tireóideos/farmacologia , Distribuição Tecidual , Vitelogênese/efeitos dos fármacos
14.
Artigo em Inglês | MEDLINE | ID: mdl-31634572

RESUMO

Dopamine plays a crucial role in controlling reproduction in eels, and its action is mediated through D2-type dopamine receptors. D2A and D2B receptors in the Japanese eel Anguilla japonica were cloned and characterized in the present study. Attention (daily expression patterns in the brain and endogenous regulation) was paid to D2B receptor because it is considered to play a crucial role in eel reproduction. The cDNAs of D2A and D2B receptors had open reading frames comprising 456 and 454 amino acid residues, respectively, which were phylogenetically clustered with those of other teleost species. Both receptors were highly expressed in the brain. D2B receptor transcript levels exhibited high day/low night variation in the midbrain and pituitary, suggesting that its transcription in these tissues is regulated in a daily manner, possibly under influence of melatonin. Intraperitoneal injection of dopamine downregulated D2B receptor transcription significantly in the midbrain and moderately in the pituitary within 1 h, but upregulated its transcription in the forebrain. Co-injection of dopamine with its antagonist (domperidone) reversed the effect of dopamine in the pituitary and forebrain, but not in the midbrain, suggesting that the effect of dopamine on D2B receptor transcription differs among brain regions. The same treatment with melatonin resulted in decreased D2B receptor transcription in the midbrain. These findings indicate that dopamine and melatonin have key roles in the daily variation in D2B receptor transcription in the brain of Japanese eel, and that they are related to a daily base secretion of hormones in the hypothalamic-pituitary-gonadal axis in this species.


Assuntos
Anguilla/genética , Encéfalo/metabolismo , Relógios Circadianos , Dopamina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Melatonina/farmacologia , Receptores de Dopamina D2/genética , Anguilla/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Depressores do Sistema Nervoso Central/farmacologia , Dopaminérgicos/farmacologia , Japão , Masculino , Filogenia , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Receptores de Dopamina D2/metabolismo
15.
J Fish Biol ; 97(4): 1027-1038, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32648600

RESUMO

Fish that inhabit shallow water are exposed to periodic changes in tidal cues, including hydrostatic pressure (HP). The present study aimed at verifying differentially expressed genes (DEGs) in the brain of the threespot wrasse Halichoeres trimaculatus (tropical species) and the honbera wrasse Halichoeres tenuispinis (temperate species), both of which were exposed to HP at 30 kPa (possible high-tide stimuli in the field) or 1 kPa (low tide) for 3 or 6 h. A de novo assembly yielded 174,710 contigs (63,530 contigs were annotated) from the brain of threespot wrasse. Following RNA sequencing, quantitative PCR confirmed DEGs that were upregulated [AT atypical cadherin 2 (FAT2)] and downregulated [neuronal leucine-rich repeat protein 3 (LRRN3), dual specificity tyrosine phosphorylation-regulated kinase 1 (DYRK), mitogen-activated protein kinase kinase 1 (MAP2K1) and phosphoinositide 3 kinase (PI3K)]. The effect of HP on the transcription of these DEGs (except for MAP2K1) disappeared within 6 h, suggesting that HP is a transitory stimulus occurring at the beginning of the tidal cycle. Similar DEG transcription was observed in the brain of honbera wrasse maintained under HP for 6 h. In situ hybridization of the brain of the threespot wrasse revealed that strong signals of MPA2K1 were seen in the telencephalon, diencephalon and pituitary, whereas those of PI3K were seen in the telencephalon, diencephalon and medulla oblongata. This result suggests that these kinases are involved in sensory function (telencephalon), somatic and visceral function (medullar oblongata) and the neuroendocrine system (diencephalon and pituitary), all of which were related to changes in HP stimuli. Following HP exposure, the transcription of c-fos increased in the pituitary of honbera wrasse, suggesting that external stimuli directly or indirectly activate hormone synthesis at the hypothalamic-pituitary-gonadal axis. It is concluded that HP alters gene expression in relation to neural development and function in the central nervous system and plays a role in exerting tidal-related reproduction and feeding in wrasses.


Assuntos
Peixes/fisiologia , Regulação da Expressão Gênica , Pressão Hidrostática , Reprodução , Animais , Encéfalo/metabolismo , Caderinas/genética , Proteínas de Peixes/genética , Perfilação da Expressão Gênica , Glicoproteínas de Membrana/genética , Perciformes/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Hipófise/metabolismo , Proteínas Quinases/genética , Reprodução/fisiologia
16.
Fish Physiol Biochem ; 46(3): 787-801, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32128660

RESUMO

The aim of this study was to investigate the expression patterns of ocular melatonin in the annual reproductive cycle of the female grass puffer. Spawning season of the female grass puffer is from June to July in Jeju, South Korea. Time-resolved fluoroimmunoassay revealed that levels of ocular melatonin, which show an annual change, peaked in May (spawning season). Additionally, expression of reproductive-related genes also showed annual patterns: GnRH1 peaked in August, GnRH2 peaked in February, GnRH3, Kiss2, and LPXRFa peaked in November. These results suggest that ocular melatonin may be related to the annual reproductive cycle in the grass puffer. To better understand the photic regulation of AANAT1a mRNA in the retina, we observed the nocturnal pattern of ocular melatonin levels daily, which shows a nocturnal pattern in both short photoperiod (SD) and long photoperiod (LD) conditions. In the brain, AANAT2 mRNA also shows a nocturnal pattern in both SD and LD; however, the time of peak expression of AANAT2 mRNA was unchanged in both conditions. Following intraperitoneal injection of melatonin for 2 weeks, expression of GnRH2 and LPXRFa mRNA in the brain significantly increased, while that of Kiss2 mRNA was decreased, suggesting that melatonin has a reproduction-related effect. Furthermore, under SD and LD conditions for 14 weeks, the gonadosomatic index more increased and the maturity of the ovary progressed under LD compared with those under SD, suggesting that the SD photoperiodic signal inactivated ovarian development. These results indicate that the ocular melatonin may have a possible role in the reproductive endocrinology of the grass puffer.


Assuntos
Olho/metabolismo , Melatonina/metabolismo , Reprodução , Takifugu/genética , Takifugu/metabolismo , Acetiltransferases/genética , Animais , Encéfalo/metabolismo , Feminino , Proteínas de Peixes/genética , Expressão Gênica , Hormônio Liberador de Gonadotropina/genética , Kisspeptinas/genética , Fotoperíodo , RNA Mensageiro/metabolismo , Reprodução/genética , Estações do Ano
17.
Fish Physiol Biochem ; 46(1): 277-291, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31705423

RESUMO

The sapphire devil (Chrysiptera cyanea) is a tropical damselfish that undergoes active reproduction under long-day conditions. To elucidate the physiological regulation of the brain-pituitary-gonadal axis in female sapphire devil, we cloned and characterized the genes of two kisspeptins (kiss1 and kiss2), three gonadotropin-releasing hormones (gnrh1, gnrh2, gnrh3), and the ß-subunit of two gonadotropins (fshß and lhß) and investigated the gene expression changes during ovarian development. Quantitative polymerase chain reaction analyses in various brain parts revealed high expression levels of kiss1, kiss2, and gnrh2 in the diencephalon; gnrh2 and gnrh3 in the telencephalon; and fshß and lhß in the pituitary. In situ hybridization (ISH) analyses revealed positive signals of kiss1 in the dorsal and ventral habenular nucleus and of kiss2 in the dorsal and ventral parts of the nucleus of the lateral recess. This analysis showed gnrh1 expression in the preoptic area (POA), suggesting that GnRH1 plays a stimulating role in the secretion of gonadotropins from the pituitary of the sapphire devil. High transcription levels of kiss1, kiss2, gnrh1, gnrh2, fshß, and lhß were observed in the brain during the late vitellogenic stage, suggesting their involvement in the physiological processes of vitellogenesis. Immersion of fish in estradiol-17ß (E2)-containing seawater resulted in increased expression of kiss2 and gnrh1 in their brains. This study showed that kiss-expressing neurons in the diencephalon are influenced by E2, leading to upregulation of gnrh1 in the POA and of fshß and lhß in the pituitary during vitellogenesis.


Assuntos
Encéfalo/fisiologia , Perciformes/fisiologia , Hipófise/fisiologia , Reprodução/fisiologia , Animais , Feminino , Peixes , Subunidade beta do Hormônio Folículoestimulante , Expressão Gênica , Hormônio Liberador de Gonadotropina , Kisspeptinas , Hormônio Luteinizante Subunidade beta , Precursores de Proteínas , Ácido Pirrolidonocarboxílico/análogos & derivados , RNA Mensageiro , Vitelogênese
18.
Artigo em Japonês | MEDLINE | ID: mdl-32963139

RESUMO

It is necessary to verify an intensity-modulated radiation therapy (IMRT) plan and to confirm dose error within the tolerance, in order to perform it securely and precisely. IMRT with dynamic multi-leaf collimator (DMLC) requires high DMLC position accuracy. The DMLC position accuracy analysis software DynaLog File Viewer (DFV; Varian Medical Systems, Palo Alto, CA, USA) is used to analyze position errors of DMLC for IMRT plans. We analyzed correlation between DMLC parameters and position error of DMLC obtained from DFV in prostate IMRT. A regression analysis of the position error and the DMLC parameters was performed. As a result, a strong correlation was found between MLC position error and each of the DMLC parameters: leaf speed, gap width, and segment monitor unit (MU). We found the factors for the DMLC position error in this study. DMLC position error could be estimated from leaf speed, gap width, and segment MU when we analyze IMRT cases in the further study.


Assuntos
Radioterapia de Intensidade Modulada , Masculino , Próstata , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Software
19.
Artigo em Japonês | MEDLINE | ID: mdl-32435034

RESUMO

Guidelines require commissioning for deformable image registration (DIR) software before clinical use. The accuracy of DIR software depends upon data used. If common datasets for the DIR commissioning are available, the DIR results using the common datasets would be useful as an accuracy benchmark. Thus, the DIR-database (DIR-DB) was developed for DIR accuracy check and was open to access, which included radiotherapy plan data. This study was approved by Institutional Review Board (IRB). The DIR-DB recorded radiotherapy plans which had been finished on June 2017 and which at least two radiotherapy plans were built for a case in a treatment course. Cone-beam computed tomography (CBCT) images for patient setup were also collected and recorded in the DIR-DB, if it is available. All recorded data were anonymized and were allowed to access by users in Japan with the IRB approval. The accuracy metrics of DIR; Hausdorff distance, mean distance to agreement, Dice similarity coefficient, Jaccard were put up on the DIR-DB web site. The number of recorded cases were 11 cases for head and neck, 16 cases for thorax, 7 cases for abdomen, 8 cases for pelvis and 6 cases for prostate treated with brachytherapy. The number of case for CBCT was 17 cases. It was meaningful for DIR accuracy check in Japan that the DIR-DB and DIR results using the data in the database were released.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Planejamento da Radioterapia Assistida por Computador , Algoritmos , Tomografia Computadorizada de Feixe Cônico , Humanos , Processamento de Imagem Assistida por Computador , Japão , Masculino , Dosagem Radioterapêutica
20.
Artigo em Japonês | MEDLINE | ID: mdl-32684559

RESUMO

PURPOSE: The aim of this study was to analyze improvement prediction on contour deformation accuracy using deformable image registration (DIR) results compared to rigid image registration (RIR) results. METHOD: Radiotherapy plans for 31 cases (seven head and neck cases, 10 chest cases, six abdomen cases and eight female pelvis cases) from the privately open database for DIR were used. These cases used at least two radiotherapy plans, and registration was performed using two plans, not only for one case but also for different cases. The DIR and RIR were performed using the DIR software MIM Maestro (MIM software Inc., Cleveland, USA). The registration results for the following organs were analyzed: eye balls, optic nerves, brain stem, spinal cord and right and left parotid glands for head and neck; right and left lungs for chest; liver and right and left kidneys for abdomen; and rectum and bladder for pelvis. Dice similarity coefficient (DSC) for the organs was calculated from the results of RIR and DIR. The improvement in the DSC was observed. RESULTS AND DISCUSSION: DIR improved the DSC values by more than 0.2 for simple shapes, well-defined boundaries and large volumes such as eye balls, brain stem, lungs and liver. The minimum DSC for these organs was approximately 0.7. The improvement in DSC for the organs eye balls, brain stem, lungs and liver had ceiling values 0.95, 0.90, 1.0 and 1.0, respectively. DSC for the spinal cord, parotid gland, bladder and kidney also improved by DIR compared to RIR; however, DIR could not improve the DSC value for rectum compared to RIR because of a large difference in the position, shape and size due to stool and gas.


Assuntos
Processamento de Imagem Assistida por Computador , Planejamento da Radioterapia Assistida por Computador , Algoritmos , Feminino , Cabeça , Pescoço
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