Publications by authors named "Marcio A Figueiredo"

Objective: To investigate the effects of maxillary orthodontic expansion on the alveolar bone tissue in adult patients treated with aligners by using cone-beam computed tomography.

Methods: Thirty patients (22 females and 8 males; mean age: 36.3 years) were treated with Invisalign aligners.

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In this report, we demonstrate the effectiveness of the Invisalign system in the treatment of severe gingival recession and bone dehiscence through torque, translation, and intrusion movements in a young woman. Cone-beam computed tomography was used to assess bone parameters and check the teeth during treatment. The root of the mandibular right central incisor, which was buccally positioned and exhibited bone dehiscence of 9.

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The brain is a highly demanding organ in terms of energy requirements, and precise regulatory mechanisms must operate to ensure adequate energy delivery to maintain normal neuronal activity. Of the energy-promoting substrates present in the circulation, glucose is preferred by the brain, and as with all other substrates, its utilization depends on the presence of humoral factors such as hormones including growth hormone (GH). Glucose enters the cells though specific transport proteins.

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The somatotropic axis, composed essentially of the growth hormone (GH) and insulin-like growth factors (IGFs), is the main regulator of somatic growth in vertebrates. However, these protein hormones are also involved in various other major physiological processes. Although the importance of IGFs in mechanisms involving tissue regeneration has already been established, little is known regarding the direct effects of GH in these processes.

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The objective of this study was to investigate the relationship between IGFs produced in the liver and skeletal muscle with muscle hypertrophy previously observed in a line of GH-transgenic zebrafish. In this sense, we evaluated the expression of genes related to the IGF system in liver and muscle of transgenics, as well as the main intracellular signaling pathways used by GH/IGF axis. Our results showed an increase in expression of igf1a, igf2a, and igf2b genes in the liver.

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Transgenic fish for growth hormone (GH) has been considered as a potential technological improvement in aquaculture. In this study, a double-transgenic zebrafish was used to evaluate the effect of GH and its receptor (GHR) on muscle growth. Double transgenics reached the same length of GH transgenic, but with significantly less weight, featuring an unbalanced growth.

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The method usually employed to stimulate gonadal maturation and spawning of captive shrimp involves unilateral eyestalk ablation, which results in the removal of the endocrine complex responsible for gonad-inhibiting hormone (GIH) synthesis and release. In the present study, RNAi technology was used to inhibit transcripts of GIH in Litopenaeus vannamei females. The effect of gene silencing on gonad development was assessed by analyzing the expression of GIH and vitellogenin, respectively, in the eyestalk and ovaries of L.

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It has been reported that nuclear translocation of growth hormone receptor (GHR) may directly activate cell proliferation in mammals and birds. However, this phenomenon has not yet been described in fish. Recently, we have developed a transgenic zebrafish that overexpresses GHR in a muscle-specific manner.

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The development of growth hormone (GH) transgenic fish has been shown to be a promising method to improve growth rates. However, the role of GH is not restricted only to processes involved in growth. Several others physiological processes, including immune function, are impaired due to GH imbalances.

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The biological actions of growth hormone (GH) are pleiotropic, including growth promotion, energy mobilization, gonadal development, appetite, and social behavior. The regulatory network for GH is complex and includes many central and peripheral endocrine factors as well as that from the environment. It is known that GH transgenesis results in increased growth, food intake, and consequent metabolic rates in fishes.

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The OCT4 transcription factor is a crucial stem cells marker and it has been related to the cancer stem cells concept. Moreover, it has also been associated to the multiple drug resistance (MDR) phenotype. Our first results pointed out a straight relation between OCT4 and ABC transporters in K562-derivative MDR (Lucena) cells.

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Growth hormone (GH) is an important regulator of immune functions in vertebrates, and it has been intensively reported a series of stimulatory actions of this hormone over on the immune system. Within aquaculture, overexpression of GH has been considered a promising alternative for promoting higher growth rates in organisms of commercial interest. Considering the various pleiotropic effects of GH, there are still few studies that aim to understand the consequences of the excess of GH on the physiological systems.

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Growth hormone (GH) transgenesis has been postulated as a biotechnological tool for improving growth performance in fish aquaculture. However, GH is implied in several other physiological processes, and transgenesis-induced GH excess could lead to unpredictable collateral effects, especially on reproductive traits. Here, we have used two-years-old transgenic zebrafish males to evaluate the effects of GH-transgenesis on spermatic parameters and reproductive success.

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The presence of higher level of exogenous growth hormone (GH) in transgenic animals could lead to several physiological alterations. A GH transgenic zebrafish (Danio rerio) line was compared to nontransgenic (NT) samples of the species through a DDRT-PCR approach, with the goal of identifying candidate differentially expressed transcripts in brain tissues that could be involved in GH overexpression. Densitometric analyses of two selected amplification products, p300 and ADCY2, pointed to a significant lower gene expression in the transgenic zebrafish (104.

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Even though growth hormone (GH) transgenesis has demonstrated potential for improved growth of commercially important species, the hormone excess may result in undesired collateral effects. In this context, the aim of this work was to develop a new model of transgenic zebrafish (Danio rerio) characterized by a muscle-specific overexpression of the GH receptor (GHR) gene, evaluating the effect of transgenesis on growth, muscle structure and expression of growth-related genes. In on line of transgenic zebrafish overexpressing GHR in skeletal muscle, no significant difference in total weight in comparison to non-transgenics was observed.

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The aim of the present study was to analyse the morphology of white skeletal muscle in males and females from the GH-transgenic zebrafish (Danio rerio) lineage F0104, comparing the expression of genes related to the somatotrophic axis and myogenesis. Histological analysis demonstrated that transgenic fish presented enhanced muscle hypertrophy when compared to non-transgenic fish, with transgenic females being more hypertrophic than transgenic males. The expression of genes related to muscle growth revealed that transgenic hypertrophy is independent from local induction of insulin-like growth factor 1 gene (igf1).

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The aim of this study was to evaluate the effects of growth hormone (GH) overexpression on the gene expression profile of multiple components of the antioxidant defense system (ADS) of different genotypes of a GH-transgenic zebrafish (Danio rerio) model. Several ADS-related genes were analyzed by semiquantitative reverse transcription-PCR in the liver of hemizygous (HE) and homozygous (HO) transgenic zebrafish. The results showed a significant reduction in the glutamate cysteine ligase catalytic subunit (GCLC) and the gene expression of two glutathione S-transferase (GST) isoforms and an increase in the glutathione reductase gene in the HO group compared to non-transgenic controls.

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Growth hormone (GH) action is the result of an intracellular cascade initiated just after its interaction with the growth hormone receptor (GHR) located on the surface of target cells. This cascade culminates with the transcription of target genes, such as the insulin-like growth factors (IGFs), which are responsible for most GH biological effects. In addition to its central role in growth, fish GH is also involved with osmoregulatory control.

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Aim: To describe the dentoskeletal changes occurring during treatment of a patient with a skeletal Class III malocclusion treated for orthodontic compensation at 10 years 4 months of age.

Methods: Rapid maxillary expansion was performed with a Hyrax appliance, Petit orthopedic face mask, high-pull chin cap, and bioprogressive fixed mechanics.

Results: The mechanics employed yielded downward and backward mandibular rotation (3 degrees of opening of the facial axis), advancement of the maxillary incisors, and retraction of the mandibular incisors.

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Aim: To describe the treatment of a 7-year-old patient with a hyperdivergent (dolichofacial) pattern, Class II Division 1 malocclusion, and anterior open bite.

Methods: Treatment was performed in 2 stages following the principles of the Ricketts bioprogressive technique and comprised early extraction of the maxillary permanent first molars and primary second molars.

Results: The treatment plan established for correction of the initial malocclusion reached the orthodontic goals, providing optimal esthetics and normal function.

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