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1.
Diagnostics (Basel) ; 13(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37835833

RESUMO

Pancreatic cancer (PC) has one of the lowest survival rates among all major types of cancer. Consequently, it is one of the leading causes of mortality worldwide. Serum biomarkers historically correlate well with the early prognosis of post-surgical complications of PC. However, attempts to identify an effective biomarker panel for the successful prognosis of PC were almost non-existent in the current literature. The current study investigated the roles of various serum biomarkers including carbohydrate antigen 19-9 (CA19-9), chemokine (C-X-C motif) ligand 8 (CXCL-8), procalcitonin (PCT), and other relevant clinical data for identifying PC progression, classified into sepsis, recurrence, and other post-surgical complications, among PC patients. The most relevant biochemical and clinical markers for PC prognosis were identified using a random-forest-powered feature elimination method. Using this informative biomarker panel, the selected machine-learning (ML) classification models demonstrated highly accurate results for classifying PC patients into three complication groups on independent test data. The superiority of the combined biomarker panel (Max AUC-ROC = 100%) was further established over using CA19-9 features exclusively (Max AUC-ROC = 75%) for the task of classifying PC progression. This novel study demonstrates the effectiveness of the combined biomarker panel in successfully diagnosing PC progression and other relevant complications among Egyptian PC survivors.

2.
Int J Mol Sci ; 24(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37895159

RESUMO

Diabetes mellitus is a metabolic disorder associated with various complications encompassing male reproductive dysfunction. The present study aimed to investigate the therapeutic potential of biologically active Lepidium sativum seed oil (LSO) against the testicular dysfunction associated with streptozotocin (STZ)-induced diabetes. Male adults (n = 24) were divided into four groups: control, LSO-administered, diabetic (D), and LSO-treated diabetic (D+LSO) groups. LSO was extracted from L. sativum seeds, and its chemical composition was determined using GC-MS. Serum testosterone levels, testicular enzymatic antioxidants (catalase (CAT) and superoxide dismutase (SOD)), an oxidative stress (OS) biomarker, malondialdehyde (MDA), pro-inflammatory markers (NF-kB, IL-1, IL-6, and TNF-α), and the expression level of NF-kB were assessed. In addition, histopathological changes were evaluated in testicular tissues. The results obtained showed that the chemical composition of LSO indicated its enrichment mainly with γ-tocopherol (62.1%), followed by 2-methylhexacosane (8.12%), butylated hydroxytoluene (8.04%), 10-Methylnonadecane (4.81%), and δ-tocopherol (3.91%). Moreover, LSO administration in the D+LSO mice significantly increased testosterone levels and ameliorated the observed testicular oxidative damage, inflammatory response, and reduced NF-kB expression compared to the diabetic mice. Biochemical and molecular analyses confirmed the histological results. In conclusion, LSO may prevent the progression of diabetes-induced impairment in the testes through inhibition of the OS- and NF-kB-mediated inflammatory response.


Assuntos
Diabetes Mellitus Experimental , Doenças Testiculares , Humanos , Camundongos , Masculino , Animais , Testículo/metabolismo , Lepidium sativum/metabolismo , NF-kappa B/metabolismo , Diabetes Mellitus Experimental/metabolismo , Estresse Oxidativo , Antioxidantes/metabolismo , Doenças Testiculares/metabolismo , Inflamação/metabolismo , Testosterona/metabolismo , Óleos de Plantas/farmacologia , Óleos de Plantas/uso terapêutico , Óleos de Plantas/metabolismo
3.
Biomedicines ; 11(9)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37760831

RESUMO

Lead (Pb)-induced reprotoxicity is a detrimental consequence of Pb exposure, which results in abnormal spermatogenesis, testicular degeneration, and pathogenic sperm changes. The association between impaired male reproductive function and Pb-induced oxidative stress (OS) has been demonstrated, with consequent testicular antioxidant deficiency. The current study investigated the protective role of the natural antioxidant hesperidin (HSD) against lead-acetate (PbAc)-induced testicular toxicity. Male Wistar rats (n = 40) were randomly divided into four experimental groups: Group I (negative control) received 2.0 mL/kg BW 0.9% saline; Group II received 100 mg/kg BW PbAc; Group III received 100 mg/kg BW HSD; and Group IV received HSD two hours before PbAc using the abovementioned doses. The treatments were administered daily for 30 consecutive days. The results showed that HSD treatment significantly restored PbAc-induced decrease in body, epididymal, and testicular weights as well as in semen parameters, reproductive hormones, and testicular markers of OS. Reduced MDA levels and improved testicular histopathological findings were also observed. Collectively, this study sheds light on the preventive role of HSD against PbAc-induced testicular injury, which is mediated via the suppression of OS and the modulation of reproductive hormones as well as the plausibility of HSD being used as a supplementary therapeutic option for recovery.

4.
J Genet Eng Biotechnol ; 20(1): 166, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36520239

RESUMO

BACKGROUND: A useful technique for growing large amounts of plant material is in vitro propagation of important medicinal plants. The present investigation deals with the enhancement of secondary metabolite production via elicitation using gamma (γ)-radiation and phenylalanine (Phe) precursor feeding in callus cultures of Silybum marianum L. RESULTS: Seeds were exposed to two doses of γ-radiation (25 and 50 Gy) and the calli derived from stem explants  obtained from seedlings of these radiated seeds were treated with different concentrations of Phe. The biosynthesis of phenols and flavonoids was evaluated. It was found that callus cultures derived from explants of the seeds exposed to 25 Gy γ-radiation and treated with 4 mg/l Phe accumulated the maximum phenolic content (34.27±0.02 mg/g d.wt.), while the highest flavonoid content (9.56±0.12 mg/g d.wt.) was found in callus cultures derived from explants of seeds radiated with 25 Gy γ-radiation and subjected to 1 mg/l Phe. Similarly, HPLC quantification revealed that the production of flavonoids was highly accumulated (1343.06 µg/mg d.wt.) in callus cultures from explants of seeds  exposed to 25 Gy γ-radiation and grown at 1 mg/l Phe compared to the other treatments. In addition, a total of 11 important flavonoids have been determined in all callus cultures, except for acacetin-7-O-rutinoside, which was not found in the callus culture of the control. CONCLUSIONS: These findings suggest that γ-radiation combined with Phe can improve the metabolism of S. marianum L. and could be used to produce such valuable metabolites on a commercial scale.

5.
J Biochem Mol Toxicol ; 35(9): e22859, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34328254

RESUMO

Clinically, the use of doxorubicin (DOX) is limited due to DOX-induced cardiotoxicity (DIC). The current study aimed to evaluate the cardioprotective effect of trehalose (TRE) against DIC in a female Swiss albino mouse model. Mice were divided into five experimental groups: Gp. I: saline control group (200 µl/mouse saline three times per week for 3 weeks day after day), Gp. II: DOX-treated group (2 mg/kg body weight three times per week for 3 weeks day after day), Gp. III: TRE group (200 µg/mouse three times per week for 3 weeks day after day), Gp. IV: DOX + TRE cotreatment group (animals were coadministered with DOX and TRE as in Gp. II and III, respectively), and Gp. V: DOX + TRE posttreatment group (animals were treated with DOX as in Gp. II followed by treatment with TRE as in Gp. III). DOX-treated mice showed significant elevation in cardiac injury biomarkers (lactate dehydrogenase, creatine kinase isoenzyme-MB, and cardiac troponin I), cardiac oxidative stress (OS) markers (malondialdehyde and myeloperoxidase), and cardiac levels of autophagy-related protein 5. Moreover, DOX significantly reduced the levels of total antioxidant capacity and activities of catalase and glutathione S-transferase. In contrast, TRE treatment of DOX-administered mice significantly improved almost all of the above-mentioned assessed parameters. Furthermore, histopathological changes of cardiac tissues observed in mice treated with TRE in combination with DOX were significantly improved as compared to DOX-treated animals. Taken together, the present study provides evidence that TRE has cardioprotective effects against DIC, which is likely mediated via suppression of OS and autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Cardiotônicos/farmacologia , Cardiotoxicidade/tratamento farmacológico , Doxorrubicina/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Trealose/farmacologia , Animais , Biomarcadores/metabolismo , Cardiotoxicidade/metabolismo , Doxorrubicina/farmacologia , Feminino , Camundongos , Miocárdio/metabolismo
6.
Nutr Cancer ; 73(5): 829-844, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32406258

RESUMO

Brown algae earned importance by virtue of their promising secondary metabolites of reasonable biological activities. Herein, the antioxidant, antimicrobial, and anticancer effects of crude extracts obtained from two Egyptian brown seaweeds, Sargassum linearifolium and Cystoseira crinita were evaluated. Phytochemical and GC-MS analyses revealed numerous active secondary metabolites in C. crinita cold methanolic extract (CCME) and S. linearifolium hot aqueous extract (SHAE). Both SHAE and CCME exhibited comparable DPPH (124.5 vs 125.6 µg/ml) and ABTS (257.1 vs 254.8 µg/ml) scavenging activities, respectively. Moreover, both crude extracts exhibited antimicrobial activity against various pathogenic microorganisms. Interestingly, employing MTT assay revealed cytotoxic effects of both extracts against a panel of cancer cells, where CCME showed a strong cytotoxic activity against MCF-7 cells (IC50 = 18.0 ± 0.74 µg/ml), while SHAE exhibited a moderate effect (IC50 = 31.1 ± 1.04 µg/ml). Increased mRNA and protein expression of Bax and Beclin-1 as well as the decreased expression of Bcl-2 revealed the ability of both extracts to induce apoptosis and autophagy in MCF-7 cells. Collectively, these findings provide evidence for antioxidant, antimicrobial, as well as anticancer effects driven by the two brown seaweeds that may underlay their plausible application in the therapeutic uses.


Assuntos
Anti-Infecciosos , Phaeophyceae , Sargassum , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Egito , Humanos , Extratos Vegetais
7.
Nutr Cancer ; 72(3): 460-480, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31318622

RESUMO

Egyptian propolis is a powerful antioxidant and free radical scavenger produced by bees. The current study was designed to characterize Egyptian propolis, investigate its anticancer effect in vitro and its protective role against methotrexate (MTX) toxicity in Ehrlich ascites carcinoma (EAC) experimental model. Our results revealed a high content of total phenolics, flavonoids and dihydroflavonols in propolis ethanolic extract (PEE). PEE prompted cytotoxic effects in cancer cell lines and antitumor effects against EAC mice model by reducing tumor volume, count of viable tumor cells with a significant elevation in the life span as well as the mean survival time of mice. The hepatic and renal biochemical and toxicity parameters of EAC-bearing mice treated with MTX were improved by PEE. Also, it elevates the expression of Bax, caspase-3 and cytochrome-C and reduces the Bcl2 expression in EAC cells. Moreover, PEE with MTX induced cell cycle arrest at the G0/G1 phase. Interestingly, the combination of PEE with MTX showed potent apoptosis as shown by DNA fragmentation gel, comet assay and dihydrofolate reductase level (DHFR). These findings demonstrate that Egyptian propolis extract had high chemical diversity and different antioxidant effects. Also, it optimizes the antitumor potential of MTX and declined its toxic effects.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Antioxidantes/farmacologia , Carcinoma de Ehrlich/patologia , Metotrexato/efeitos adversos , Própole/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Apoptose/efeitos dos fármacos , Abelhas , Carcinoma de Ehrlich/tratamento farmacológico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Egito , Metotrexato/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Própole/química
8.
Appl Biochem Biotechnol ; 189(1): 87-102, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30868382

RESUMO

Protease-producing Staphylococcus sciuri was isolated from poultry soil samples and culture conditions for protease production were optimized. The isolated protease showed a maximum activity of 235.1 U/ml. Enzyme purification procedure involved ammonium sulphate precipitation and Sephacryl S-200 HR gel filtration chromatography (GFC). The purification process resulted in the production of three protease fractions namely protease І (metallo-alkaline protease), II, and IІІ. The metallo-alkaline protease was purified to 25.49-fold with specific activity of 982.22 U/mg and 3.76% recovery. The partially purified metallo-protease was optimally active at pH 10.0 and 70 °C and exhibited thermal stability up to 50 °C. The protease activity was enhanced by Ca2+ and Mg2+, completely inhibited by Hg2+ and Cu2+, and significantly reduced by EDTA. The protease showed significant stability towards various surfactants, including SDS. The Km and Vmax values were 0.68 mg/ml and 166.66 nmol of azocasein/ml/h, respectively, while the activation energy (Ea) was 3.07 Kcal/mol. Hence, it is evident that the produced protease possesses unique characteristics and could be a plausible candidate for various industrial and biotechnological applications.


Assuntos
Adaptação Fisiológica , Metaloproteases/metabolismo , Staphylococcus/enzimologia , Cromatografia em Gel , Concentração de Íons de Hidrogênio , Metaloproteases/biossíntese , Metaloproteases/isolamento & purificação , Proteólise , Temperatura
9.
Environ Sci Pollut Res Int ; 24(31): 24272-24283, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28889190

RESUMO

Exposure to either lead (Pb) or γ-irradiation (IR) results in oxidative stress in biological systems. Herein, we explored the potential anti-apoptotic effect of spermine (Spm) against lead and/or γ-irradiation-induced hepatotoxicity in male albino rats. Rats were divided into eight experimental groups of ten rats each: groups including negative control, whole body γ-irradiated (6 Gray (Gy)), lead acetate (PbAct) trihydrate orally administered (75 mg/kg bw ≡ 40 mg/kg bw Pb for 14 consecutive days), and Spm intraperitoneally dosed (10 mg/kg bw for 14 consecutive days) rats and groups subjected to combinations of Pb + IR, Spm + IR, Spm + Pb, and Spm + Pb followed by IR on day 14 (Spm + Pb + IR). A significant decrease in arginase activity as well as mRNA and protein levels of Bcl-2 and p21 was observed in rats intoxicated with Pb and/or γ-irradiation compared to controls, whereas Bax mRNA and protein levels were significantly increased. Also, an increased level of nitric oxide (NO) with a reduced arginase activity was observed in liver tissues of intoxicated rats. Spm co-treatment with lead and/or γ-irradiation attenuated the increase in Bax mRNA and protein expression, while it restored those of Bcl-2 and p21 together with NO levels and arginase activity to control values. Altogether, we suggest that Spm may be useful in combating free radical-induced apoptosis in Pb-intoxicated and/or γ-irradiated rats.


Assuntos
Apoptose/efeitos dos fármacos , Raios gama/efeitos adversos , Chumbo/toxicidade , Fígado/metabolismo , Substâncias Protetoras/farmacologia , Espermina/farmacologia , Animais , Fígado/efeitos dos fármacos , Masculino , Ratos , Irradiação Corporal Total/efeitos adversos
10.
Best Pract Res Clin Endocrinol Metab ; 31(2): 143-159, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28648504

RESUMO

Developmental anomalies of the thyroid gland, defined as thyroid dysgenesis, underlie the majority of cases of congenital hypothyroidism. Thyroid dysgenesis is predominantly a sporadic disorder although a reported familial enrichment, variation of incidence by ethnicity and the monogenic defects associated mainly with athyreosis or orthotopic thyroid hypoplasia, suggest a genetic contribution. Of note, the most common developmental anomaly, thyroid ectopy, remains unexplained. Ectopy may result from multiple genetic or epigenetic variants in the germline and/or at the somatic level. This review provides a brief overview of the monogenic defects in candidate genes that have been identified so far and of the syndromes which are known to be associated with thyroid dysgenesis.


Assuntos
Morfogênese/fisiologia , Disgenesia da Tireoide/genética , Glândula Tireoide/embriologia , Animais , Hipotireoidismo Congênito/epidemiologia , Hipotireoidismo Congênito/genética , Feminino , Estudos de Associação Genética , Humanos , Hipotireoidismo/epidemiologia , Hipotireoidismo/etiologia , Incidência , Masculino , Doenças da Glândula Tireoide/complicações , Doenças da Glândula Tireoide/epidemiologia , Doenças da Glândula Tireoide/genética , Disgenesia da Tireoide/embriologia , Disgenesia da Tireoide/epidemiologia , Glândula Tireoide/anormalidades , Glândula Tireoide/crescimento & desenvolvimento
11.
J Clin Pathol ; 68(6): 434-40, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25770162

RESUMO

AIMS: CD133 expression in cancer is frequently associated with poor outcome. Thyroid carcinomas are rare in childhood and adolescence and are associated with a higher risk of recurrence and more metastases than the adult tumours. The aim of the study was to assess whether the expression of CD133 in thyroid carcinomas of children, adolescents and young adults was correlated with clinical prognostic factors. METHODS: Tissue microarrays were constructed with 235 tumours coming from 208 young adults with a median age of 28 years and 27 children with a median age of 13 years. An immunohistochemical study was performed with anti-CD133 antibody. CD133 expression was evaluated, using a semiquantitative score based on the percentage of positive cells. The mutation status of tumours was evaluated by reverse transcriptase PCR. Three cell lines were used to confirm CD133 expression by western blot. RESULTS: CD133 expression was found in 43% of adult and 37% of child tumours and was confirmed by western blot in cell lines. In young adults, the expression of CD133 was significantly more frequent in patients with tumours >3 cm (p=0.04) and in patients with lymph node metastases (p=0.02). The expression of CD133 was more frequent in patients in whom the tumour presented a BRAF mutation (p=0.03). CONCLUSIONS: CD133 expression is correlated with tumour size, lymph nodes metastases and BRAF mutations in young adults. The presence of these cancer stem cells could offer new therapeutic alternatives for aggressive thyroid cancers.


Assuntos
Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Glicoproteínas/metabolismo , Peptídeos/metabolismo , Neoplasias da Glândula Tireoide/diagnóstico , Antígeno AC133 , Adolescente , Adulto , Carcinoma/diagnóstico , Carcinoma/genética , Carcinoma Papilar , Linhagem Celular Tumoral , Criança , Feminino , Humanos , Metástase Linfática , Masculino , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Câncer Papilífero da Tireoide , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/genética , Adulto Jovem
12.
Endocrinology ; 156(1): 377-88, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25353184

RESUMO

Congenital hypothyroidism caused by thyroid dysgenesis (CHTD) is a common congenital disorder with a birth prevalence of 1 case in 4000 live births, and up to 8% of individuals with CHTD have co-occurring congenital heart disease. Initially we found nine patients with cardiac and thyroid congenital disorders in our cohort of 158 CHTD patients. To enrich for a rare phenotype likely to be genetically simpler, we selected three patients with a ventricular septal defect for molecular studies. Then, to assess whether rare de novo copy number variants and coding mutations in candidate genes are a source of genetic susceptibility, we used a genome-wide single-nucleotide polymorphism array and Sanger sequencing to analyze blood DNA samples from selected patients with co-occurring CHTD a congenital heart disease. We found rare variants in all three patients, and we selected Netrin-1 as the biologically most plausible contributory factor for functional studies. In zebrafish, ntn1a and ntn1b were not expressed in thyroid tissue, but ntn1a was expressed in pharyngeal arch mesenchyme, and ntn1a-deficient embryos displayed defective aortic arch artery formation and abnormal thyroid morphogenesis. The functional activity of the thyroid in ntn1a-deficient larvae was, however, preserved. Phenotypic analysis of affected zebrafish indicates that abnormal thyroid morphogenesis resulted from a lack of proper guidance exerted by the dysplastic vasculature of ntn1a-deficient embryos. Hence, careful phenotyping of patients combined with molecular and functional studies in zebrafish identify Netrin-1 as a potential shared genetic factor for cardiac and thyroid congenital defects.


Assuntos
Anormalidades Cardiovasculares/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Genótipo , Fatores de Crescimento Neural/metabolismo , Disgenesia da Tireoide/genética , Proteínas Supressoras de Tumor/metabolismo , Animais , Animais Geneticamente Modificados , Feminino , Técnicas de Silenciamento de Genes , Predisposição Genética para Doença , Humanos , Masculino , Morfolinos , Fatores de Crescimento Neural/genética , Netrina-1 , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sinaptotagminas/genética , Sinaptotagminas/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas de Peixe-Zebra
13.
J Clin Endocrinol Metab ; 99(6): E1120-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24646064

RESUMO

BACKGROUND: Discordance of monozygotic twins for thyroid dysgenesis suggests that epigenetic mechanisms may underlie defects in thyroid gland development. This prompted us to evaluate whether differentially methylated regions (DMRs) can be found between human thyroids (either eutopic or ectopic) and matched leukocytes. METHODS: To compare the genome-wide methylation profile of thyroids and leukocytes, immunoprecipitated methylated DNA was interrogated on human promoter plus CpG island tiling arrays. In addition, the methylation profile of the human FOXE1, PAX8, and NKX2.1 promoter was examined using bisulfite sequencing. Finally, the functional impact of CpG methylation of the promoter on FOXE1 expression was assessed with luciferase assays. RESULTS: Genome-wide methylation profiling and bisulfite sequencing of CpG islands of PAX8 and NKX2.1 promoters revealed no DMR between thyroid and leukocytes. However, bisulfite sequencing revealed that the methylation level of two consecutive CpG dinucleotides (CpG14 and CpG15, which were not covered by the genome-wide array) in one CpG island of the FOXE1 promoter (-1600 to -1140 from the transcription start site) is significantly higher in leukocytes than in eutopic or ectopic thyroid tissues, suggesting that methylation of this region may decrease FOXE1 gene expression. Indeed, luciferase activities were decreased when FOXE1 promoter constructs were methylated in vitro. Moreover, derepression of luciferase activity was observed when the methylation of CpG14 and CpG15 was prevented by mutations. CONCLUSION: We report a tissue-dependent DMR in the FOXE1 promoter. This DMR contains two consecutive CpG dinucleotides, which are epigenetic modifiers of FOXE1 expression in nontumoral tissues.


Assuntos
Metilação de DNA , Fatores de Transcrição Forkhead/genética , Leucócitos/metabolismo , Glândula Tireoide/metabolismo , Animais , Células Cultivadas , Ilhas de CpG , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica , Humanos , Células K562 , Especificidade de Órgãos/genética , Regiões Promotoras Genéticas , Ratos
14.
J Clin Endocrinol Metab ; 97(3): 951-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22238389

RESUMO

CONTEXT: The thyroid contains two types of cells, the thyroid follicular cells and the calcitonin-producing cells. The site of origin of the thyroid follicular cells is the median thyroid anlage, an endothelial diverticulum in the midline of the ventral pharynx between the first and the second pharyngeal pouches. The ultimobranchial bodies (UBB), a pair of transient embryonic structures evaginated from the fourth pharyngeal pouch and located symmetrically on the sides of the developing neck, are the source of calcitonin-producing cells. In human embryos, the thyroid bud starts its migration at embryonic day 24 and reaches its final location in front of the trachea at embryonic day 45-50. The UBB fuse with the primitive thyroid when thyroid migration is completed. Lingual thyroids result from the failure of the thyroid precursor cells to migrate from the primordial pharynx to the anterior part of the neck. Therefore, calcitonin-producing cells are not expected to be present in lingual thyroids. OBJECTIVE: Our objective was to determine whether calcitonin-producing C cells are present in ectopic lingual thyroids. DESIGN, SETTING, PATIENTS, AND MAIN OUTCOME MEASURE: We performed calcitonin immunolabeling and transcript detection on four flash-frozen ectopic lingual thyroids. Additional calcitonin immunolabeling was performed on two other paraffin-embedded ectopic lingual thyroids. RESULTS: We report evidence of calcitonin-producing cells in six independent cases of ectopic lingual thyroids. CONCLUSION: The UBB are not the only source of calcitonin-producing cells in humans. Interactions between calcitonin-producing and thyroid follicular cells occur earlier than previously accepted.


Assuntos
Calcitonina/metabolismo , Tireoide Lingual/metabolismo , Adolescente , Adulto , Calcitonina/genética , Criança , Feminino , Humanos , Tireoide Lingual/patologia , Masculino
15.
PLoS One ; 5(10): e13420, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20976176

RESUMO

BACKGROUND: Congenital hypothyroidism from thyroid dysgenesis (CHTD) is predominantly a sporadic disease characterized by defects in the differentiation, migration or growth of thyroid tissue. Of these defects, incomplete migration resulting in ectopic thyroid tissue is the most common (up to 80%). Germinal mutations in the thyroid-related transcription factors NKX2.1, FOXE1, PAX-8, and NKX2.5 have been identified in only 3% of patients with sporadic CHTD. Moreover, a survey of monozygotic twins yielded a discordance rate of 92%, suggesting that somatic events, genetic or epigenetic, probably play an important role in the etiology of CHTD. METHODOLOGY/PRINCIPAL FINDINGS: To assess the role of somatic genetic or epigenetic processes in CHTD, we analyzed gene expression, genome-wide methylation, and structural genome variations in normal versus ectopic thyroid tissue. In total, 1011 genes were more than two-fold induced or repressed. Expression array was validated by quantitative real-time RT-PCR for 100 genes. After correction for differences in thyroid activation state, 19 genes were exclusively associated with thyroid ectopy, among which genes involved in embryonic development (e.g. TXNIP) and in the Wnt pathway (e.g. SFRP2 and FRZB) were observed. None of the thyroid related transcription factors (FOXE1, HHEX, NKX2.1, NKX2.5) showed decreased expression, whereas PAX8 expression was associated with thyroid activation state. Finally, the expression profile was independent of promoter and CpG island methylation and of structural genome variations. CONCLUSIONS/SIGNIFICANCE: This is the first integrative molecular analysis of ectopic thyroid tissue. Ectopic thyroids show a differential gene expression compared to that of normal thyroids, although molecular basis could not be defined. Replication of this pilot study on a larger cohort could lead to unraveling the elusive cause of defective thyroid migration during embryogenesis.


Assuntos
Metilação de DNA , Perfilação da Expressão Gênica , Genômica , Glândula Tireoide/metabolismo , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Mutação , Fatores de Transcrição/genética
16.
J Pediatr ; 155(4): 593-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19773006

RESUMO

A term infant was born with respiratory distress, and subsequent imaging, histopathologic, and hormonal studies confirmed congenital hypothyroidism. This report is intended to alert pediatricians to the possibility of congenital hypothyroidism as a cause of respiratory symptoms of unknown cause in neonates with respiratory distress.


Assuntos
Hipotireoidismo Congênito/complicações , Hipotireoidismo Congênito/diagnóstico , Doenças Pulmonares Intersticiais/etiologia , Insuficiência Respiratória/etiologia , Hipotireoidismo Congênito/terapia , Humanos , Recém-Nascido , Doenças Pulmonares Intersticiais/patologia , Doenças Pulmonares Intersticiais/terapia , Masculino , Insuficiência Respiratória/patologia , Insuficiência Respiratória/terapia
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