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1.
Proc Biol Sci ; 291(2021): 20240235, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38654650

RESUMO

Terror birds (Aves, Phorusrhacidae) were large flightless apex predators in South America during the Cenozoic. Here, we estimate a new phylogeny for phorusrhacids using Bayesian inference. We demonstrate phylogenetic evidence for a monophyletic Patagornithinae and find significant support for a distinct crown group associated with the quintessential 'terror bird' characteristics. We use this phylogeny to analyse the evolution of body size and cursoriality. Our results reveal that size overlap was rare between co-occurring subfamilies, supporting the hypothesis that these traits were important for niche partitioning. We observe that gigantism evolved in a single clade, containing Phorusrhacinae and Physornithinae. The members of this lineage were consistently larger than all other phorusrhacids. Phorusrhacinae emerged following the extinction of Physornithinae, suggesting the ecological succession of the apex predator niche. The first known phorusrhacine, Phorusrhacos longissimus, was gigantic but significantly smaller and more cursorial than any physornithine. These traits likely evolved in response to the expansion of open environments. Following the Santacrucian SALMA, phorusrhacines increased in size, further converging on the morphology of Physornithinae. These findings suggest that the evolution and displacement of body size drove terror bird niche partitioning and competitive exclusion controlled phorusrhacid diversity.


Assuntos
Evolução Biológica , Tamanho Corporal , Filogenia , Animais , Passeriformes/fisiologia , Teorema de Bayes , América do Sul , Aves/fisiologia
2.
Best Pract Res Clin Endocrinol Metab ; 38(3): 101892, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521632

RESUMO

It is usually considered that only 5% of all pituitary neuroendocrine tumours are due to inheritable causes. Since this estimate was reported, however, multiple genetic defects driving syndromic and nonsyndromic somatotrophinomas have been unveiled. This heterogeneous genetic background results in overlapping phenotypes of GH excess. Genetic tests should be part of the approach to patients with acromegaly and gigantism because they can refine the clinical diagnoses, opening the possibility to tailor the clinical conduct to each patient. Even more, genetic testing and clinical screening of at-risk individuals have a positive impact on disease outcomes, by allowing for the timely detection and treatment of somatotrophinomas at early stages. Future research should focus on determining the actual frequency of novel genetic drivers of somatotrophinomas in the general population, developing up-to-date disease-specific multi-gene panels for clinical use, and finding strategies to improve access to modern genetic testing worldwide.


Assuntos
Acromegalia , Testes Genéticos , Gigantismo , Humanos , Acromegalia/genética , Acromegalia/diagnóstico , Acromegalia/terapia , Gigantismo/genética , Gigantismo/diagnóstico , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/diagnóstico , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Adenoma Hipofisário Secretor de Hormônio do Crescimento/diagnóstico , Adenoma Hipofisário Secretor de Hormônio do Crescimento/terapia
3.
JCEM Case Rep ; 1(2): luad034, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37908467

RESUMO

Acromegaly/giantism results from the chronic excess of growth hormone (GH) and insulin-like growth factor-1 (IGF-1), in more than 96% of cases, due to a GH-secreting pituitary adenoma. Primary treatment of choice is transsphenoidal resection of the adenoma. More than 30% to 40% of operated cases require adjunctive forms of treatment, be it pharmacological or radiotherapeutical. The multimodal treatment of acromegaly has resulted in substantial improvements in the quality of life and life expectancy of these patients. We herein present the complex case of a patient with acromegaly due to a mammosomatotrope adenoma, with a germ-line AIP (aryl hydrocarbon receptor-interacting protein) mutation, who had a chronic and protracted course of more than 15 years during which he was treated with surgery, somatostatin receptor ligands, dopamine agonist, and the GH receptor antagonist pegvisomant. At one point, he was able to come off medications and was even found to be transiently GH-deficient, only to develop acromegaly again after a couple of years.

4.
Ann Bot ; 132(7): 1233-1248, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-37818893

RESUMO

BACKGROUND AND AIMS: Gigantism is a key component of the domestication syndrome, a suite of traits that differentiates crops from their wild relatives. Allometric gigantism is strongly marked in horticultural crops, causing disproportionate increases in the size of edible parts such as stems, leaves or fruits. Tomato (Solanum lycopersicum) has attracted attention as a model for fruit gigantism, and many genes have been described controlling this trait. However, the genetic basis of a corresponding increase in size of vegetative organs contributing to isometric gigantism has remained relatively unexplored. METHODS: Here, we identified a 0.4-Mb region on chromosome 7 in introgression lines (ILs) from the wild species Solanum pennellii in two different tomato genetic backgrounds (cv. 'M82' and cv. 'Micro-Tom') that controls vegetative and reproductive organ size in tomato. The locus, named ORGAN SIZE (ORG), was fine-mapped using genotype-by-sequencing. A survey of the literature revealed that ORG overlaps with previously mapped quantitative trait loci controlling tomato fruit weight during domestication. KEY RESULTS: Alleles from the wild species led to lower cell number in different organs, which was partially compensated by greater cell expansion in leaves, but not in fruits. The result was a proportional reduction in leaf, flower and fruit size in the ILs harbouring the alleles from the wild species. CONCLUSIONS: Our findings suggest that selection for large fruit during domestication also tends to select for increases in leaf size by influencing cell division. Since leaf size is relevant for both source-sink balance and crop adaptation to different environments, the discovery of ORG could allow fine-tuning of these parameters.


Assuntos
Gigantismo , Solanum lycopersicum , Solanum , Solanum lycopersicum/genética , Tamanho do Órgão/genética , Gigantismo/genética , Locos de Características Quantitativas/genética , Solanum/genética , Frutas/genética
5.
BMC Ecol Evol ; 23(1): 62, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37872505

RESUMO

BACKGROUND: Cetaceans (whales, porpoises, and dolphins) are a lineage of aquatic mammals from which some species became giants. Only recently, gigantism has been investigated from the molecular point of view. Studies focused mainly on coding regions, and no data on the influence of regulatory regions on gigantism in this group was available. Accordingly, we investigated the molecular evolution of non-coding regulatory regions of genes already described in the literature for association with size in mammals, focusing mainly on the promoter regions. For this, we used Ciiider and phyloP tools. Ciiider identifies significantly enriched transcription factor binding sites, and phyloP estimates the molecular evolution rate of the promoter. RESULTS: We found evidence of enrichment of transcription binding factors related to large body size, with distinct patterns between giant and non-giant cetaceans in the IGFBP7 and NCAPG promoters, in which repressive agents are present in small cetaceans and those that stimulate transcription, in giant cetaceans. In addition, we found evidence of acceleration in the IGF2, IGFBP2, IGFBP7, and ZFAT promoters. CONCLUSION: Our results indicate that regulatory regions may also influence cetaceans' body size, providing candidate genes for future research to understand the molecular basis of the largest living animals.


Assuntos
Golfinhos , Toninhas , Animais , Evolução Biológica , Baleias , Sequências Reguladoras de Ácido Nucleico , Regiões Promotoras Genéticas/genética , Aceleração
6.
Medisur ; 20(1)feb. 2022.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1405885

RESUMO

RESUMEN Tanto el gigantismo como la acromegalia pueden deberse a una secreción excesiva de hormona del crecimiento por parte de la hipófisis anterior. Cuando los afectados son jóvenes en edades próximas al cierre de los cartílagos se manifiestan signos y síntomas de gigantismo y de acromegalia. Se presenta el caso de un paciente masculino de 20 años de edad atendido en el Servicio de Endocrinología del Hospital Gustavo Aldereguia Lima de Cienfuegos con manifestaciones clínicas de alta talla, crecimiento acral e hipertensión arterial. Se le realizó prueba de tolerancia oral a la glucosa que midió hormona de crecimiento y confirmó el exceso hormonal. La resonancia magnética contrastada con gadolinio informó macroadenoma hipofisario. Se diagnosticó como gigantismo acromegaloide por un tumor hipofisario productor de hormona del crecimiento. Se realizó exéresis del macroadenoma, con evolución favorable. Es indiscutible la importancia del diagnóstico precoz de esta enfermedad, pues acorta la esperanza de vida, aumenta la mortalidad global no solo por la hipersecreción hormonal, sino también por el efecto de masa del tumor.


ABSTRACT Both gigantism and acromegaly can be due to excessive secretion of growth hormone by the anterior pituitary. When those affected are young, close to cartilage closure, signs and symptoms of gigantism and acromegaly appear. The case of a 20-year-old male patient treated in the Endocrinology Service of the Gustavo Aldereguia Lima Hospital in Cienfuegos with clinical manifestations of tall stature, acral growth and arterial hypertension is presented. An oral glucose tolerance test was performed that measured growth hormone and confirmed the excess of hormones. Gadolinium-enhanced MRI reported pituitary macroadenoma. It was diagnosed as acromegaloid gigantism due to a growth hormone-producing pituitary tumor. The macroadenoma was excised, with a favorable evolution. The importance of early diagnosis of this disease is indisputable, since it shortens life expectancy, increases global mortality not only due to hormonal hypersecretion, but also due to the mass effect of the tumor.

7.
Am J Med Genet A ; 185(12): 3916-3923, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34405946

RESUMO

Sotos syndrome is characterized by overgrowth starting before birth through childhood with intellectual disability and craniofacial anomalies. The majority of patients are large for gestational age with developmental delay or intellectual disability. The majority of cases are caused by pathogenic variants in NSD1. The most consistent physical features in this disorder are facial dysmorphisms including prominent forehead, downslanted palpebral fissures, prognathism with a pointed chin, and a long and narrow face. We present a follow-up to a cohort of 11 individuals found to harbor heterozygous, pathogenic, or likely pathogenic variants in NSD1. We analyzed the facial dysmorphisms and the condition using retrospective over 20 years. Among these patients, followed in our medical genetics outpatient clinic for variable periods of time, all had a phenotype compatible with the characteristic Sotos syndrome facial features, which evolved with time and became superimposed with natural aging modifications. We present here a long-term follow-up of facial features of Brazilian patients with molecularly confirmed Sotos syndrome. In this largest Brazilian cohort of molecularly confirmed patients with Sotos syndrome to date, we provide a careful description of the facial phenotype, which becomes less pronounced with aging and possibly more difficult to recognize in adults. These results may have broad clinical implications for diagnosis and add to the global clinical delineation of this condition.


Assuntos
Anormalidades Craniofaciais/genética , Predisposição Genética para Doença , Histona-Lisina N-Metiltransferase/genética , Síndrome de Sotos/genética , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Anormalidades Craniofaciais/diagnóstico por imagem , Anormalidades Craniofaciais/fisiopatologia , Deficiências do Desenvolvimento/complicações , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/fisiopatologia , Face/diagnóstico por imagem , Face/fisiopatologia , Feminino , Seguimentos , Transtornos do Crescimento/complicações , Transtornos do Crescimento/genética , Transtornos do Crescimento/fisiopatologia , Humanos , Lactente , Deficiência Intelectual/complicações , Deficiência Intelectual/genética , Deficiência Intelectual/fisiopatologia , Masculino , Fenótipo , Síndrome de Sotos/diagnóstico por imagem , Síndrome de Sotos/fisiopatologia
8.
Am J Bot ; 108(2): 200-215, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33598914

RESUMO

PREMISE: The Caribbean islands are in the top five biodiversity hotspots on the planet; however, the biogeographic history of the seasonally dry tropical forest (SDTF) there is poorly studied. Consolea consists of nine species of dioecious, hummingbird-pollinated tree cacti endemic to the West Indies, which form a conspicuous element of the SDTF. Several species are threatened by anthropogenic disturbance, disease, sea-level rise, and invasive species and are of conservation concern. However, no comprehensive phylogeny yet exists for the clade. METHODS: We reconstructed the phylogeny of Consolea, sampling all species using plastomic data to determine relationships, understand the evolution of key morphological characters, and test their biogeographic history. We estimated divergence times to determine the role climate change may have played in shaping the current diversity of the clade. RESULTS: Consolea appears to have evolved very recently during the latter part of the Pleistocene on Cuba/Hispaniola likely from a South American ancestor and, from there, moved into the Bahamas, Jamaica, Puerto Rico, Florida, and the Lesser Antilles. The tree growth form is a synapomorphy of Consolea and likely aided in the establishment and diversification of the clade. CONCLUSIONS: Pleistocene aridification associated with glaciation likely played a role in shaping the current diversity of Consolea, and insular gigantism may have been a key innovation leading to the success of these species to invade the often-dense SDTF. This in-situ Caribbean radiation provides a window into the generation of species diversity and the complexity of the SDTF community within the Antilles.


Assuntos
Filogenia , Animais , Bahamas , Região do Caribe , Florida , Porto Rico , Índias Ocidentais
9.
Mol Biol Evol ; 38(1): 84-95, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33035304

RESUMO

Reconstructing the evolutionary history of island biotas is complicated by unusual morphological evolution in insular environments. However, past human-caused extinctions limit the use of molecular analyses to determine origins and affinities of enigmatic island taxa. The Caribbean formerly contained a morphologically diverse assemblage of caviomorph rodents (33 species in 19 genera), ranging from ∼0.1 to 200 kg and traditionally classified into three higher-order taxa (Capromyidae/Capromyinae, Heteropsomyinae, and Heptaxodontidae). Few species survive today, and the evolutionary affinities of living and extinct Caribbean caviomorphs to each other and to mainland taxa are unclear: Are they monophyletic, polyphyletic, or paraphyletic? We use ancient DNA techniques to present the first genetic data for extinct heteropsomyines and heptaxodontids, as well as for several extinct capromyids, and demonstrate through analysis of mitogenomic and nuclear data sets that all sampled Caribbean caviomorphs represent a well-supported monophyletic group. The remarkable morphological and ecological variation observed across living and extinct caviomorphs from Cuba, Hispaniola, Jamaica, Puerto Rico, and other islands was generated through within-archipelago evolutionary radiation following a single Early Miocene overwater colonization. This evolutionary pattern contrasts with the origination of diversity in many other Caribbean groups. All living and extinct Caribbean caviomorphs comprise a single biologically remarkable subfamily (Capromyinae) within the morphologically conservative living Neotropical family Echimyidae. Caribbean caviomorphs represent an important new example of insular mammalian adaptive radiation, where taxa retaining "ancestral-type" characteristics coexisted alongside taxa occupying novel island niches. Diversification was associated with the greatest insular body mass increase recorded in rodents and possibly the greatest for any mammal lineage.


Assuntos
DNA Antigo/análise , Roedores/genética , Animais , Filogeografia , Índias Ocidentais
10.
Mol Biol Evol ; 38(5): 1715-1730, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33169792

RESUMO

Gigantism results when one lineage within a clade evolves extremely large body size relative to its small-bodied ancestors, a common phenomenon in animals. Theory predicts that the evolution of giants should be constrained by two tradeoffs. First, because body size is negatively correlated with population size, purifying selection is expected to be less efficient in species of large body size, leading to increased mutational load. Second, gigantism is achieved through generating a higher number of cells along with higher rates of cell proliferation, thus increasing the likelihood of cancer. To explore the genetic basis of gigantism in rodents and uncover genomic signatures of gigantism-related tradeoffs, we assembled a draft genome of the capybara (Hydrochoerus hydrochaeris), the world's largest living rodent. We found that the genome-wide ratio of nonsynonymous to synonymous mutations (ω) is elevated in the capybara relative to other rodents, likely caused by a generation-time effect and consistent with a nearly neutral model of molecular evolution. A genome-wide scan for adaptive protein evolution in the capybara highlighted several genes controlling postnatal bone growth regulation and musculoskeletal development, which are relevant to anatomical and developmental modifications for an increase in overall body size. Capybara-specific gene-family expansions included a putative novel anticancer adaptation that involves T-cell-mediated tumor suppression, offering a potential resolution to the increased cancer risk in this lineage. Our comparative genomic results uncovered the signature of an intragenomic conflict where the evolution of gigantism in the capybara involved selection on genes and pathways that are directly linked to cancer.


Assuntos
Evolução Biológica , Tamanho Corporal/genética , Genoma , Roedores/genética , Animais , Feminino , Crescimento/genética , Família Multigênica , Neoplasias/genética , Roedores/crescimento & desenvolvimento
11.
Pituitary ; 24(2): 252-261, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33156432

RESUMO

PURPOSE: Non-syndromic pituitary gigantism (PG) is a very rare disease. Aryl hydrocarbon receptor-interacting protein (AIP) and G protein-coupled receptor 101 (GPR101) genetic abnormalities represent important etiologic causes of PG and may account for up to 40% of these cases. Here, we aimed to characterize the clinical and molecular findings and long-term outcomes in 18 patients (15 males, three females) with PG followed at a single tertiary center in Sao Paulo, Brazil. METHODS: Genetic testing for AIP and GPR101 were performed by DNA sequencing, droplet digital PCR and array comparative genomic hybridization (aCGH). RESULTS: Pathogenic variants in the AIP gene were detected in 25% of patients, including a novel variant in splicing regulatory sequences which was present in a sporadic male case. X-LAG due to GPR101 microduplication was diagnosed in two female patients (12.5%). Of interest, these patients had symptoms onset by age 5 and 9 years old and diagnosis at 5 and 15 years, respectively. X-LAG, but not AIP, patients had a significantly lower age of symptoms onset and diagnosis and a higher height Z-score when compared to non-X-LAG. No other differences in clinical features and/or treatment outcomes were observed among PG based on their genetic background. CONCLUSION: We characterize the clinical and molecular findings and long-term outcome of the largest single-center PG cohort described so far.


Assuntos
Gigantismo/genética , Gigantismo/patologia , Adolescente , Adulto , Brasil , Criança , Hibridização Genômica Comparativa , Feminino , Testes Genéticos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Imageamento por Ressonância Magnética , Masculino , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/patologia , Receptores Acoplados a Proteínas G/genética , Adulto Jovem
12.
J Exp Biol ; 223(Pt 11)2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32366692

RESUMO

Whale sharks (Rhincodon typus) - the largest extant fish species - reside in tropical environments, making them an exception to the general rule that animal size increases with latitude. How this largest fish thrives in tropical environments that promote high metabolism but support less robust zooplankton communities has not been sufficiently explained. We used open-source inertial measurement units (IMU) to log 397 h of whale shark behavior in Yucatán, Mexico, at a site of both active feeding and intense wildlife tourism. Here we show that the strategies employed by whale sharks to compensate for the increased drag of an open mouth are similar to ram feeders five orders of magnitude smaller and one order of magnitude larger. Presumed feeding constituted 20% of the total time budget of four sharks, with individual feeding bouts lasting up to 11 consecutive hours. Compared with normal, sub-surface swimming, three sharks increased their stroke rate and amplitude while surface feeding, while one shark that fed at depth did not demonstrate a greatly increased energetic cost. Additionally, based on time-depth budgets, we estimate that aerial surveys of shark populations should consider including a correction factor of 3 to account for the proportion of daylight hours that sharks are not visible at the surface. With foraging bouts generally lasting several hours, interruptions to foraging during critical feeding periods may represent substantial energetic costs to these endangered species, and this study presents baseline data from which management decisions affecting tourist interactions with whale sharks may be made.


Assuntos
Tubarões , Natação , Animais , Espécies em Perigo de Extinção , Masculino , México
13.
Growth Horm IGF Res ; 50: 48-56, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31864177

RESUMO

The aim of this article is to present a historical review on giants and dwarves living in South America and the contribution of South America's researchers to scientific advances on growth hormone (GH) and human disorders related to GH excess and GH deficiency (GHD). We went back in time to investigate facts and myths stemming from countless reports of giants who lived in the Patagonia region, focusing on what is currently known about gigantism in South America. Additionally, we have reviewed the exceptional work carried out in two of the world's largest cohorts of dwarfism related to GH-IGF axis: one living in Itabaianinha, Brazil, suffering from severe GHD due to a mutation in the GHRH receptor (GHRHR) gene, and the other living in El Oro and Loja provinces of Ecuador, who are carriers of GH receptor gene mutation that causes total GH insensitivity (Laron syndrome). Importantly, we present an overview of the outstanding medical contribution of Jose Dantas de Souza Leite, a Brazilian physician that described the first cases of acromegaly, and Bernardo Alberto Houssay, an Argentine researcher graced with the Nobel Prize, who was one the first scientists to establish a link between GH and glucose metabolism.


Assuntos
Acromegalia/história , Nanismo Hipofisário/história , Endocrinologia/história , Gigantismo/história , Pesquisa Biomédica , Transtornos do Crescimento/história , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Síndrome de Laron/história , Prêmio Nobel , América do Sul
14.
Arch. endocrinol. metab. (Online) ; 63(4): 385-393, July-Aug. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1019354

RESUMO

ABSTRACT Introduction Gigantism is a rare pediatric disease characterized by increased production of growth hormone (GH) before epiphyseal closure, that manifests clinically as tall stature, musculoskeletal abnormalities, and multiple comorbidities. Materials and methods Case series of 6 male patients with gigantism evaluated at the Endocrinology Service of Hospital de San José (Bogotá, Colombia) between 2010 and 2016. Results All patients had macroadenomas and their mean final height was 2.01 m. The mean age at diagnosis was 16 years, and the most common symptoms were headache (66%) and hyperhidrosis (66%). All patients had acral changes, and one had visual impairment secondary to compression of the optic chiasm. All patients underwent surgery, and 5 (83%) required additional therapy for biochemical control, including radiotherapy (n = 4, 66%), somatostatin analogues (n = 5, 83%), cabergoline (n = 3, 50%), and pegvisomant (n = 2, 33%). Three patients (50%) achieved complete biochemical control, while 2 patients showed IGF-1 normalization with pegvisomant. Two patients were genetically related and presented a mutation in the aryl hydrocarbon receptor-interacting protein (AIP) gene (pathogenic variant, c.504G>A in exon 4, p.Trp168*), fulfilling the diagnostic criteria of familial isolated pituitary adenoma. Conclusions This is the largest case series of patients with gigantism described to date in Colombia. Transsphenoidal surgery was the first-choice procedure, but additional pharmacological therapy was usually required. Mutations in the AIP gene should be considered in familial cases of GH-producing adenomas.


Assuntos
Humanos , Masculino , Adolescente , Adulto Jovem , Neoplasias Hipofisárias/terapia , Adenoma/terapia , Gigantismo/terapia , Linhagem , Neoplasias Hipofisárias/diagnóstico , Fator de Crescimento Insulin-Like I/análise , Hormônio do Crescimento/sangue , Adenoma/diagnóstico , Estudos Retrospectivos , Seguimentos , Resultado do Tratamento , Distribuição por Sexo , Colômbia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Gigantismo/diagnóstico , Mutação/genética
15.
Artigo em Inglês | MEDLINE | ID: mdl-30941100

RESUMO

Human phosphodiesterases (PDEs) comprise a complex superfamily of enzymes derived from 24 genes separated into 11 PDE gene families (PDEs 1-11), expressed in different tissues and cells, including heart and brain. The isoforms PDE4, PDE7, and PDE8 are specific for the second messenger cAMP, which is responsible for mediating diverse physiological actions involving different hormones and neurotransmitters. The cAMP pathway plays an important role in the development and function of endocrine tissues while phosphodiesterases are responsible for ensuring the appropriate intensity of the actions of this pathway by hydrolyzing cAMP to its inactive form 5'-AMP. PDE1, PDE2, PDE4, and PDE11A are highly expressed in the pituitary, and overexpression of some PDE4 isoforms have been demonstrated in different pituitary adenoma subtypes. This observed over-expression in pituitary adenomas, although of unknown etiology, has been considered a compensatory response to tumorigenesis. PDE4A4/5 has a unique interaction with the co-chaperone aryl hydrocarbon receptor-interacting protein (AIP), a protein implicated in somatotroph tumorigenesis via germline loss-of-function mutations. Based on the association of low PDE4A4 expression with germline AIP-mutation-positive samples, the available data suggest that lack of AIP hinders the upregulation of PDE4A4 protein seen in sporadic somatotrophinomas. This unique disturbance of the cAMP-PDE pathway observed in the majority of AIP-mutation positive adenomas could contribute to their well-described poor response to somatostatin analogs and may support a role in tumorigenesis.

16.
Zootaxa ; 4387(3): 499-510, 2018 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-29690477

RESUMO

The genus Pseudacanthicus currently comprises the following six species distributed in the Amazon and Tocantins basins, and coastal drainages from Guyana to French Guyana: P. serratus, P. fordii, P. histrix, P. spinosus, P. leopardus, P. pitanga, and P. pirarara. Herein we describe P. major, from rio Tocantins basin, one of the largest loricariid species known. The new species is distinguished from its congeners by the following combination of characters: having body color pattern with dark brown background without spots or blotches and dorsal and caudal fins with transversal white bands; anterior process of compound pterotic with no contacting with the posterior margin of the orbit and by the absence of a conspicuous crest on the posterior edge of parieto-supraocciptal. Other osteological characteristics are further used to diagnose P. major from others congeners. A discussion on gigantism and miniaturization in freshwater fish, ornamental fisheries activities, threats and conservation of the new species are also provided.


Assuntos
Peixes-Gato , Animais , Brasil , Guiana Francesa , Água Doce , Guiana
17.
Clinics ; Clinics;72(4): 218-223, Apr. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-840068

RESUMO

OBJECTIVE: To evaluate the effectiveness of the treatment of acromegaly patients at the Federal University of Triangulo Mineiro. METHODS: Cross-sectional and retrospective study of thirty cases treated over a period of two decades. RESULTS: 17 men (56.7%) aged 14-67 years and 13 women aged 14-86 years were analyzed. Twenty-one patients underwent transphenoidal surgery, whichwas associated with somatostatin receptor ligands in 11 patients (39.3%), somatostatin receptor ligands + radiotherapyin 5 patients (17.8%), radiotherapy in 3 patients (10.7%), and radiotherapy + somatostatin receptorligands + cabergoline in 1 patient (3.6%). Additionally, 2 patients underwent radiotherapy and surgeryalone. Six patients received somatostatin receptor ligands before surgery, and 2 were not treated due to refusal and death. Nine patients have died, and 20 are being followed; 13 (65%) have growth hormonelevels o1 ng/mL, and 11 have normal insulin-like growth factor 1 levels. CONCLUSION: The current treatment options enable patients seen in regional reference centers to achieve strict control parameters, which allows them to be treated close to their homes.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Acromegalia/terapia , Adenoma/cirurgia , Adenoma Hipofisário Secretor de Hormônio do Crescimento/cirurgia , Receptores de Somatostatina/metabolismo , Acromegalia/sangue , Adenoma/metabolismo , Glicemia/análise , Brasil , Terapia Combinada , Estudos Transversais , Gigantismo/sangue , Gigantismo/terapia , Hormônio do Crescimento/sangue , Fator de Crescimento Insulin-Like I/análise , Ligantes , Estudos Retrospectivos , Resultado do Tratamento
18.
Pituitary ; 20(1): 22-32, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27812777

RESUMO

BACKGROUND: Acromegaly is a rare and underdiagnosed disorder caused, in more than 95% of cases, by a growth hormone (GH)-secreting pituitary adenoma. The GH hypersecretion leads to overproduction of insulin-like growth factor 1 (IGF-1) which results in a multisystem disease characterized by somatic overgrowth, multiple comorbidities, physical disfigurement, and increased mortality. OBJECTIVE: This article aims to review the clinical features of acromegaly at diagnosis. DISCUSSION/CONCLUSION: Acromegaly affects both males and females equally and the average age at diagnosis ranges from 40 to 50 years (up to 5% of cases < the age 20). Due to insidious onset and slow progression, acromegaly is often diagnosed five to more than ten years after its onset. The typical coarsening of facial features include furrowing of fronthead, pronounced brow protrusion, enlargement of the nose and the ears, thickening of the lips, skin wrinkles and nasolabial folds, as well as mandibular prognathism that leads to dental malocclusion and increased interdental spacing. Excessive growth of hands and feet (predominantly due to soft tissue swelling) is present in the vast majority of acromegalic patients. Gigantism accounts for up to 5% of cases and occurs when the excess of GH becomes manifest in the young, before the epiphyseal fusion. The disease also has rheumatologic, cardiovascular, respiratory, neoplastic, neurological, and metabolic manifestations which negatively impact its prognosis and patients quality of life. Less than 15% of acromegalic patients actively seek medical attention for change in appearance or enlargement of the extremities. The presentation of acromegaly is more often related to its systemic comorbidities or to local tumor effects.


Assuntos
Acromegalia/diagnóstico , Acromegalia/patologia , Feminino , Gigantismo/diagnóstico , Gigantismo/patologia , Humanos , Masculino
19.
Pituitary ; 19(5): 507-14, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27287035

RESUMO

INTRODUCTION: Pituitary gigantism is a rare condition caused by growth hormone secreting hypersecretion, usually by a pituitary tumor. Acromegaly and gigantism cases that have a genetic cause are challenging to treat, due to large tumor size and poor responses to some medical therapies (e.g. AIP mutation affected cases and those with X-linked acrogigantism syndrome). MATERIALS AND METHODS: We performed a retrospective study to identify gigantism cases among 160 somatotropinoma patients treated between 1985 and 2015 at the University Hospital of Caracas, Venezuela. We studied clinical details at diagnosis, hormonal responses to therapy and undertook targeted genetic testing. Among the 160 cases, eight patients (six males; 75 %) were diagnosed with pituitary gigantism and underwent genetic analysis that included array comparative genome hybridization for Xq26.3 duplications. RESULTS: All patients had GH secreting pituitary macroadenomas that were difficult to control with conventional treatment options, such as surgery or primary somatostatin receptor ligand (SRL) therapy. Combined therapy (long-acting SRL and pegvisomant) as primary treatment or after pituitary surgery and radiotherapy permitted the normalization of IGF-1 levels and clinical improvement. Novel AIP mutations were the found in three patients. None of the patients had Xq26.3 microduplications. CONCLUSIONS: Treatment of pituitary gigantism is frequently challenging; delayed control increases the harmful effects of GH excess, such as, excessive stature and symptom burden, so early diagnosis and effective treatment are particularly important in these cases.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Gigantismo/tratamento farmacológico , Hormônio do Crescimento Humano/análogos & derivados , Octreotida/uso terapêutico , Adolescente , Adulto , Quimioterapia Combinada , Feminino , Gigantismo/genética , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Estudos Retrospectivos , Adulto Jovem
20.
Endocrine ; 53(2): 402-11, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27033541

RESUMO

Although aryl hydrocarbon receptor-interacting protein (AIP) mutations are rare in sporadic acromegaly, their prevalence among young patients is nonnegligible. The objectives of this study were to evaluate the frequency of AIP mutations in a cohort of Mexican patients with acromegaly with disease onset before the age of 30 and to search for molecular abnormalities in the AIP gene in teeth obtained from the "Tampico Giant". Peripheral blood DNA from 71 patients with acromegaly (51 females) with disease onset <30 years was analysed (median age of disease onset of 23 years) and correlated with clinical, biochemical and imaging characteristics. Sequencing was also carried out in DNA extracted from teeth of the Tampico Giant. Five patients (7 %) harboured heterozygous, germline mutations of the AIP gene. In two of them (a 9-year-old girl with gigantism and a young man with symptoms of GH excess since age 14) the c.910C>T (p.Arg304Ter), well-known truncating mutation was identified; in one of these two cases and her identical twin sister, the mutation proved to be a de novo event, since neither of their parents were found to be carriers. In the remaining three patients, new mutations were identified: a frameshift mutation (c.976_977insC, p.Gly326AfsTer), an in-frame deletion (c.872_877del, p.Val291_Leu292del) and a nonsense mutation (c.868A > T, p.Lys290Ter), which are predicted to be pathogenic based on in silico analysis. Patients with AIP mutations tended to have an earlier onset of acromegaly and harboured larger and more invasive tumours. A previously described genetic variant of unknown significance (c.869C > T, p.Ala299Val) was identified in DNA from the Tampico Giant. The prevalence of AIP mutations in young Mexican patients with acromegaly is similar to that of European cohorts. Our results support the need for genetic evaluation of patients with early onset acromegaly.


Assuntos
Acromegalia/genética , Gigantismo/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Adenoma/genética , Adolescente , Adulto , Feminino , Frequência do Gene , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Humanos , Masculino , México , Mutação , Adulto Jovem
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