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BACKGROUND AND OBJECTIVES: Despite the obligate iron loss from blood donation, some donors present with hyperferritinaemia that can result from a wide range of acute and chronic conditions including hereditary haemochromatosis (HH). The objective of our study was to investigate the causes of hyperferritinaemia in the blood donor population and explore the value of extensive HH mutational analyses. MATERIALS AND METHODS: Forty-nine consecutive donors (f = 6, m = 43) were included prospectively from the Capital Regional Blood Center. Inclusion criteria were a single ferritin value >1000 µg/l or repeated hyperferritinaemia with at least one value >500 µg/l. All donors were questioned about their medical history and underwent a physical examination, biochemical investigations and next-generation sequencing of HH-related genes, including the HFE gene, the haemojuvelin gene (HFE2/HJV), the hepcidin gene (HAMP), the ferroportin 1 gene (SLC40A1) and the transferrin receptor 2 gene (TFR2). RESULTS: Forty of 49 donors were mutation positive with a combined 69 mutations, 54 of which were located in the HFE gene. There were 11 mutations in the TFR2 gene, two mutations in the HFE2 gene and two mutations in the HAMP gene. Only four donors had apparent alternative causes of hyperferritinaemia. CONCLUSION: HH-related mutations were the most frequent cause of hyperferritinaemia in a Danish blood donor population, and it appears that several different HH-genotypes can contribute to hyperferritinaemia. HH screening in blood donors with high ferritin levels could be warranted. HH-related iron overload should not in itself result in donor ineligibility.
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Doadores de Sangue , Genótipo , Hemocromatose/genética , Sobrecarga de Ferro/genética , Adulto , Idoso , Proteínas de Transporte de Cátions/genética , Feminino , Proteínas Ligadas por GPI/genética , Hemocromatose/sangue , Proteína da Hemocromatose , Hepcidinas/genética , Humanos , Sobrecarga de Ferro/sangue , Masculino , Pessoa de Meia-Idade , Taxa de MutaçãoRESUMO
This corrects the article DOI: 10.1038/bjc.2012.109.
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BACKGROUND: We assessed the development in the number of new base of tongue squamous-cell carcinoma (BSCC) cases per year in eastern Denmark from 2000 to 2010 and whether HPV may explain any observable increased incidence. METHODS: We performed HPV DNA PCR and p16 immunohistochemistry analysis for all (n=210) BSCCs registered in the Danish Head and Neck Cancer Group (DAHANCA) and the Danish Pathology Data Bank, and genotyped all HPV-positive specimens with amplicon-based next-generation sequencing. RESULTS: The overall crude incidence of BSCCs increased significantly (5.4% per year) during the study period. This was explained by a significant increase in the number of HPV-positive BSCCs (8.1% per year), whereas the number of HPV-negative BSCCs did not increase significantly. The overall HPV prevalence was 51%, with HPV16 as the predominant HPV type. CONCLUSIONS: The increased number of HPV-positive BSCCs may explain the increasing incidence of BSCCs in eastern Denmark, 2000-2010.
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Alphapapillomavirus/isolamento & purificação , Neoplasias da Língua/epidemiologia , Alphapapillomavirus/genética , Dinamarca/epidemiologia , Humanos , Incidência , Neoplasias da Língua/virologiaRESUMO
STUDY QUESTION: Is the ovarian reserve in a woman at a given age associated with her mother's age at menopause? SUMMARY ANSWER: We demonstrated a significant, positive association between age at maternal menopause and serum anti-Müllerian hormone (AMH) levels and antral follicle count (AFC) in daughters. The rate of decline in serum-AMH level and AFC is also associated with age at maternal menopause. WHAT IS KNOWN AND WHAT THIS PAPER ADDS: The association between menopausal age in mothers and daughters has been established through several epidemiological studies. This paper shows that early maternal menopause is related to an advanced depletion of the ovarian reserve and that late maternal menopause is related to a delayed depletion. STUDY DESIGN AND SIZE: Cross-sectional data were obtained from a prospective cohort study of 863 women. The study comprised 527 participants from this prospective cohort whose mothers' age at natural menopause was known. PARTICIPANTS, SETTING AND METHODS: Participants were recruited from female health care workers aged 20-40 years employed at Copenhagen University Hospital, Rigshospitalet, and were enrolled in the study between September 2008 and February 2010. The response rate was 52.1%. Endocrine and ovarian parameters related to reproductive ageing (AMH and AFC) were assessed by serum AMH analyses and transvaginal ovarian sonography on cycle Day 2-5. Data on reproductive history, including age at natural maternal menopause, were obtained through an internet-based questionnaire. We used an analysis of covariance model with serum-AMH and AFC as outcomes, age as the quantitative predictor and onset of maternal menopause as the categorical predictor, with further adjustments for BMI, use of oral contraceptives, participants' smoking habits and prenatal smoking exposure. MAIN FINDINGS: We found a significant effect of age at maternal menopause on both serum AMH levels (P < 0.001) and AFC (P = 0.005). Median serum-AMH concentration declined by 8.6% per year [95% confidence interval (CI): 6.4-10.8%, P < 0.001] in the group with early maternal menopausal age (≤ 45 years), by 6.8% per year (95% CI: 5.0-8.6%, P < 0.001) in the group with normal maternal menopausal age (46-54 years) and by 4.2% per year (95% CI: 2.0-6.4%, P < 0.001) in the group with late maternal menopausal age (≥ 55 years). Median AFC declined by 5.8% per year (95% CI: 4.0-7.5%, P < 0.001) in the group with early maternal menopausal age (≤ 45 years), by 4.7% per year (95% CI: 3.3-6.1%, P < 0.001) in the group with normal maternal menopausal age (46-54 years) and by 3.2% per year (95% CI: 1.4-4.9%, P < 0.001) in the group with late maternal age (≥ 55 years) at menopause. BIAS, LIMITATIONS AND GENERALIZABILITY: Information on 'age at maternal menopause' was obtained retrospectively and may be prone to recall bias and digit preference. The study population consisted of health care workers, which implies a potential selection bias. Finally, the cross-sectional nature of the data limits the generalizability. STUDY FUNDING/POTENTIAL COMPETING INTERESTS: This study was co-financed by PhD scholarships where funding was covered by the Danish Agency for Science, Technology and Innovation, Copenhagen Graduate School of Health Science (CGSHS) and the Fertility Clinic at Copenhagen University Hospital, Rigshopitalet. No competing interests are declared.
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Envelhecimento , Hormônio Antimülleriano/sangue , Regulação para Baixo , Saúde da Família , Menopausa , Folículo Ovariano/diagnóstico por imagem , Insuficiência Ovariana Primária/diagnóstico , Adulto , Biomarcadores/sangue , Estudos de Coortes , Estudos Transversais , Dinamarca/epidemiologia , Diagnóstico Precoce , Feminino , Pessoal de Saúde , Hospitais Universitários , Humanos , Menopausa Precoce , Mães , Valor Preditivo dos Testes , Insuficiência Ovariana Primária/sangue , Insuficiência Ovariana Primária/diagnóstico por imagem , Insuficiência Ovariana Primária/epidemiologia , Estudos Prospectivos , Ultrassonografia , Adulto JovemRESUMO
BACKGROUND: Although the role of human papilloma virus (HPV) in cervical squamous cell carcinoma (CSCC) is well established, the role in head and neck SCC (HNSCC) is less clear. MicroRNAs (miRNAs) have a role in the cancer development, and HPV status may affect the miRNA expression pattern in HNSCC. To explore the influence of HPV in HNSCC, we made a comparative miRNA profile of HPV-positive (HPV+) and HPV-negative (HPV-) HNSCC against CSCC. METHODS: Fresh frozen and laser microdissected-paraffin-embedded samples obtained from patients with HPV+/HPV- HNSCC, CSCC and controls were used for microarray analysis. Differentially expressed miRNAs in the HPV+ and HPV- HNSCC samples were compared with the differentially expressed miRNAs in the CSCC samples. RESULTS: Human papilloma virus positive (+) HNSCC had a distinct miRNA profile compared with HPV- HNSCC. Significantly more similarity was seen between HPV+ HNSCC and CSCC than HPV- and CSCC. A set of HPV core miRNAs were identified. Of these especially the miR-15a/miR-16/miR195/miR-497 family, miR-143/miR-145 and the miR-106-363 cluster appear to be important within the known HPV pathogenesis. CONCLUSION: This study adds new knowledge to the known pathogenic pathways of HPV and substantiates the oncogenic role of HPV in subsets of HNSCCs.
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Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Neoplasias de Cabeça e Pescoço/genética , MicroRNAs/genética , Papillomaviridae/genética , Infecções por Papillomavirus/genética , Adolescente , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/virologia , Estudos de Casos e Controles , Criança , DNA Viral/genética , Feminino , Perfilação da Expressão Gênica , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Microdissecção e Captura a Laser , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Infecções por Papillomavirus/virologia , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo RealRESUMO
It remains controversial whether anti-Müllerian hormone (AMH) concentration is influenced by hormonal contraception. This study quantified the effect of hormonal contraception on both endocrine and sonographic ovarian reserve markers in 228 users and 504 non-users of hormonal contraception. On day 2-5 of the menstrual cycle or during withdrawal bleeding, blood sampling and transvaginal sonography was performed. After adjusting for age, ovarian reserve parameters were lower among users than among non-users of hormonal contraception: serum AMH concentration by 29.8% (95% CI 19.9 to 38.5%), antral follicle count (AFC) by 30.4% (95% CI 23.6 to 36.7%) and ovarian volume by 42.2% (95% CI 37.8 to 46.3%). AFC in all follicle size categories (small, 2-4 mm; intermediate, 5-7 mm; large, 8-10 mm) was lower in users than in non-users of hormonal contraception. A negatively linear association was observed between duration of hormonal-contraception use and ovarian reserve parameters. No dose-response relation was found between the dose of ethinyloestradiol and AMH or AFC. This study indicates that ovarian reserve markers are lower in women using sex steroids for contraception. Thus, AMH concentration and AFC may not retain their accuracy as predictors of ovarian reserve in women using hormonal contraception. Serum anti-Müllerian hormone (AMH) concentration is an indirect marker of the number of small follicles in the ovary and thereby the ovarian reserve. The AMH concentration is now widely used as one of the markers of the ovarian reserve in ovarian hormonal stimulation regimens. Hence the AMH concentration in a patient is used to decide the dose of the ovarian hormonal stimulation prior to IVF treatment. In some infertile patients, hormonal contraception is used prior to ovarian hormonal stimulation and therefore it is important to clarify whether serum AMH concentration is influenced by the use of sex steroids. The aim of this study was to quantify the potential effect of hormonal contraception on the ovarian function by hormonal analyses and ovarian ultrasound examination. Examinations were performed in the early phase of the menstrual cycle or the hormone-free interval of hormonal contraception. We compared the AMH concentration, the antral follicle count (AFC) and the ovarian volume in 228 users versus 504 non-users of hormonal contraception. Users of hormonal contraception had 29.8% lower AMH concentration, 30.4% lower AFC and 42.2% lower ovarian volume than non-users. These findings were more pronounced with increasing duration of hormonal contraception. No dose-response relation was found between the dose of ethinylestradiol and the impact on serum AMH and AFC. The study indicates that ovarian reserve markers are lower in women using sex steroids for contraception. Thus, serum AMH concentration and AFC may not retain their accuracy as predictors of the ovarian reserve in women using hormonal contraception.
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Anticoncepcionais Femininos/efeitos adversos , Anticoncepcionais Orais Hormonais/efeitos adversos , Estrogênios/efeitos adversos , Ovário/efeitos dos fármacos , Insuficiência Ovariana Primária/induzido quimicamente , Adulto , Hormônio Antimülleriano/sangue , Biomarcadores/sangue , Estudos de Coortes , Anticoncepcionais Femininos/administração & dosagem , Dispositivos Anticoncepcionais Femininos/efeitos adversos , Anticoncepcionais Orais Combinados/administração & dosagem , Anticoncepcionais Orais Combinados/efeitos adversos , Anticoncepcionais Orais Hormonais/administração & dosagem , Dinamarca , Estrogênios/administração & dosagem , Etinilestradiol/administração & dosagem , Etinilestradiol/efeitos adversos , Feminino , Pessoal de Saúde , Humanos , Tamanho do Órgão/efeitos dos fármacos , Folículo Ovariano/citologia , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/efeitos dos fármacos , Ovário/citologia , Ovário/diagnóstico por imagem , Ovário/patologia , Insuficiência Ovariana Primária/sangue , Insuficiência Ovariana Primária/diagnóstico por imagem , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Tempo , Ultrassonografia , Adulto JovemRESUMO
OBJECTIVE: To prospectively evaluate the performance of first-trimester combined screening for trisomy 21 using the biochemical markers pregnancy-associated plasma protein-A (PAPP-A) and free beta-human chorionic gonadotropin (free ß-hCG) obtained before and at the time of the nuchal translucency (NT) scan. METHODS: Three fetal medicine departments in Denmark participated in the study. Screening for trisomy 21 was set up as a two-step approach with blood sampling performed before the NT scan (early sample) and again at the time of the NT scan (late sample). PAPP-A and free ß-hCG were measured on both the early and late samples. Age-standardized detection and false-positive rates for different screening protocols were calculated. RESULTS: We collected two blood samples in 27 pregnancies affected by trisomy 21 and in 3891 control pregnancies. The early samples were taken between gestational ages 8 + 0 and 13 + 6 weeks, and the late samples between 11 + 3 and 14 + 6 weeks. The median interval between the samples was 17 (range, 1-40) days. We found a significantly better estimated screening performance when using early sampling vs late sampling (P < 0.05). With a risk cut-off of 1 in 100, at the time of the risk assessment the estimated detection and false-positive rates when using the early sample were 91% (95% CI, 81-98%) and 1.6% (95% CI, 1.3-2.0%), respectively. For fixed false-positive rates the highest detection rates were achieved using both blood samples. When comparing early sampling vs double sampling there was no significant difference in screening performance. CONCLUSION: In combined first-trimester screening for trisomy 21, use of early sampling with measurement of PAPP-A and free ß-hCG before the time of the NT scan can optimize screening performance. Using maternal serum markers obtained both before and at the time of the NT scan has the potential to further improve performance, but larger studies are needed to confirm this potential.
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Gonadotropina Coriônica Humana Subunidade beta/sangue , Síndrome de Down/diagnóstico , Proteína Plasmática A Associada à Gravidez/análise , Diagnóstico Pré-Natal/métodos , Adulto , Biomarcadores/sangue , Dinamarca , Síndrome de Down/sangue , Síndrome de Down/diagnóstico por imagem , Feminino , Humanos , Medição da Translucência Nucal , Gravidez , Primeiro Trimestre da Gravidez , Estudos Prospectivos , Medição de Risco , Ultrassonografia Pré-NatalRESUMO
BACKGROUND: MicroRNAs (miRNAs) are small non-coding RNAs, which regulate mRNA translation/decay, and may serve as biomarkers. We characterised the expression of miRNAs in clinically sampled oral and pharyngeal squamous cell carcinoma (OSCC and PSCC) and described the influence of human papilloma virus (HPV). METHODS: Biopsies obtained from 51 patients with OSCC/PSCC and 40 control patients were used for microarray analysis. The results were correlated to clinical data and HPV status. Supervised learning by support vector machines was employed to generate a diagnostic miRNA signature. RESULTS: One hundred and fourteen miRNAs were differentially expressed between OSCC and normal oral epithelium, with the downregulation of miR-375 and upregulation of miR-31 as the most significant aberrations. Pharyngeal squamous cell carcinoma exhibited 38 differentially expressed miRNAs compared with normal pharyngeal epithelium. Differences in the miRNA expression pattern of both normal epithelium and SCC were observed between the oral cavity compared with the pharynx. Human papilloma virus infection revealed perturbations of 21 miRNAs, most significantly in miR-127-3p and miR363. A molecular classifier including 61 miRNAs was generated for OSCC with an accuracy of 93%. CONCLUSION: MicroRNAs may serve as useful biomarkers in OSCC and PSCC. The influence of HPV on miRNA may provide a mechanism for the distinct clinical behaviour of HPV-infected tumours.
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Carcinoma de Células Escamosas/genética , MicroRNAs/biossíntese , Neoplasias Bucais/genética , Neoplasias Faríngeas/genética , Feminino , Expressão Gênica , Humanos , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
The aim of this study was to investigate endothelial lipase (EL, LIPG) and lipoprotein lipase (LPL) mRNA and protein expression in normal human testis and testicular germ cell tumours (GCT). Both EL and LPL were expressed in normal seminiferous tubules and in the interstitial compartment. EL mRNA and protein were found in all germ cells as well as in Sertoli and Leydig cells. EL mRNA was abundant in pre-invasive carcinoma in situ (CIS) cells and GCTs, and EL protein was present in the cytoplasm of these cells. LPL mRNA was also relatively abundant in germ cells, Sertoli cells, CIS cells and GCTs. The LPL protein, however, was restricted to the cell membranes of pachytene spermatocytes and spermatids in normal tubules, absent from CIS cells and scarcely represented in tumours. The distribution of LPL protein in non-seminomas resembled the distribution of OCT3/4, a marker of embryonal carcinoma. The results suggest that both EL and LPL participate in the supply of nutrients and steroidogenesis in the testes, and that especially EL may be important for the supply of cholesterol for testosterone production in the Leydig cells. The partial cellular separation of the expression of the two lipases in normal testis suggests the existence of distinct biological roles, perhaps developmentally regulated, as indicated by the LPL expression in GCTs with embryonic features. A high expression of EL and abundance of lipid in tubules with CIS may have a diagnostic value.
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Lipase/genética , Lipase Lipoproteica/genética , Neoplasias Testiculares/metabolismo , Testículo/metabolismo , Carcinoma Embrionário/metabolismo , Carcinoma Embrionário/patologia , Endotélio/metabolismo , Células Germinativas/metabolismo , Humanos , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Células Intersticiais do Testículo/patologia , Lipase/metabolismo , Lipase Lipoproteica/metabolismo , Masculino , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Embrionárias de Células Germinativas/patologia , Óxido Nítrico Sintase Tipo III , RNA Mensageiro/metabolismo , Túbulos Seminíferos/metabolismo , Seminoma/metabolismo , Seminoma/patologia , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Células de Sertoli/patologia , Espermatócitos/metabolismo , Neoplasias Testiculares/patologia , Testículo/citologiaRESUMO
This preliminary prospective study investigated serum anti-Müllerian hormone (AMH) through correlations to other basal parameters (123 patients) and according to ovarian response to 75 IU recombinant follicle-stimulating hormone (rFSH)/day (62 patients) in ovulatory patients' first rFSH treatment cycle before intrauterine insemination. Mean age of the patients was 33 years. Serum AMH significantly correlated to age (r=-0.38), antral follicle count (AFC) (r=0.68), ovarian volume (r=0.40), FSH (r=-0.31), (P<0.001) and cycle length (r=0.26, P=0.004). Serum AMH median (interquartile range; IQR) was 8.5 pmol/l (1.9-15.1) in hyporesponders (one mature follicle) versus 10.7 (7.3-17.3) in normal responders (2-3 follicles, with a maximum of two follicles 18 mm and no need for dose reduction) and 13.4 (4.4-24.2) in hyperresponders (>2-3 mature follicles or dose reduction). There was a significant trend over response groups for body weight (P=0.005), body mass index (P=0.035), AFC (P=0.031) and FSH (P=0.001). Serum AMH median (IQR) was 10.6 pmol/l (6.9-18.2) in the 23 patients who achieved an ongoing pregnancy versus 10.5 (5.9-17.2) in the 100 non-pregnant women. Serum AMH may not be the best marker of the ovarian response in these patients.
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Hormônio Antimülleriano/sangue , Hormônio Foliculoestimulante/administração & dosagem , Inseminação Artificial , Ovulação , Adulto , Relação Dose-Resposta a Droga , Feminino , Humanos , Gravidez , Estudos ProspectivosRESUMO
Antibodies against the common active site of cholecystokinin (CCK) and gastrin stain three endocrine cell-types in the gut: G-cells (that synthesize gastrin) I-cells (that synthesize CCK), and TG-cells (whose product is unknown). In order to examine whether TG-cells either process progastrin or proCCK in a specific manner, or express a novel gastrin-CCK related hormone, we studied the distal porcine ileum, which have far more TG- than G- and I-cells. Ileal CCK and gastrin mRNA corresponded to those of the antroduodenal mucosa. Gel, ion-exchange and reversed-phase chromatography monitored with sequence-specific immunoassays showed that the ileal mucosa on average contain 0.3 and 7.6 pmol/g progastrin and proCCK, respectively; 1.1 and 13.5 pmol/g glycine-extended intermediates; and 1.1 and 24.8 pmol/g of bioactive carboxyamidated gastrin and CCK, respectively. Gastrin was present only as non-sulfated gastrin-34, whereas CCK occurred in forms similar to those of the proximal intestine. Although ileal progastrin processing is tissue specific, the amounts of gastrin and CCK are too small to explain the TG-cells. Moreover, since the ileal extracts were without traces of other peptides having the C-terminus common to gastrin and CCK, the results suggest that TG-cells produce a peptide, which is only weakly related to gastrin and CCK.
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Colecistocinina/biossíntese , Gastrinas/biossíntese , Íleo/metabolismo , Sequência de Aminoácidos , Animais , Cromatografia em Gel , Hormônios/análise , Íleo/citologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Precursores de Proteínas/metabolismo , RNA Mensageiro/análise , SuínosRESUMO
The fat mouse strain exhibits a late-onset obesity syndrome associated with a mutation in the gene encoding carboxypeptidase E (CPE). Since CPE plays a central role in the biosynthesis of a number of regulatory peptides, including gastrin, we examined the biogenesis and processing of progastrin in fat/fat mice by measuring gastrin mRNA, carboxyamidated gastrin and its processing intermediates in the stomach. The tissue concentration of carboxyamidated (i.e. bioactive) gastrin was only slightly reduced (601 +/- 28 pmol/g in fat/fat mice vs. 715 +/- 43 pmol/g in wild-type controls). However, progastrin processing intermediates accumulated excessively with an 86-fold increase in the concentration of the CPE substrate, glycyl-arginine extended gastrin, and a seven-fold increase in the concentration of glycine-extended gastrin. Accordingly, the total progastrin product was doubled, as was the concentration of gastrin mRNA. Plasma concentrations of carboxyamidated gastrin were, however slightly reduced both in fasted fat/fat mice and postprandially. The results show that the CPE mutation diminishes the efficiency of progastrin processing, but gastrin synthesis is nevertheless increased to maintain an almost normal production of bioactive gastrins. By comparison with other neuroendocrine prohormones, progastrin processing in CPE-deficient mice is unique. Hence, the increase of glycine-extended gastrin in combination with normal levels of carboxyamidated gastrin suggests that G-cells may have another biosynthetic pathway for gastrin.
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Carboxipeptidases/genética , Gastrinas/metabolismo , Precursores de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Animais , Carboxipeptidase H , Carboxipeptidases/deficiência , Gastrinas/sangue , Gastrinas/genética , Heterozigoto , Camundongos , Camundongos Mutantes , Precursores de Proteínas/sangue , Precursores de Proteínas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
The fat mouse strain exhibits a late-onset obesity syndrome associated with a mutation in the gene encoding carboxypeptidase E (CPE). CPE plays a central role in the biosynthesis of many regulatory peptides. Therefore, we examined the processing of procholecystokinin (proCCK) in the brain (neurons) and small intestine (endocrine cells) of fat/fat mice. In the brain, bioactive CCK was markedly reduced (7.9+/-1.0 pmol/g in fat/fat mice vs. 82.5+/-11.2 pmol/g in controls), but the concentration of the CPE substrate, glycylarginine-extended CCK, was elevated 105-fold. In contrast, the concentration of bioactive CCK in intestinal endocrine cells was unaffected. Endocrine cell processing was, nevertheless, altered with a 33-fold increase in glycyl-arginine-extended CCK. Interestingly, although total proCCK products were normal in the brain they were elevated 3-fold in the intestine, indicating that biosynthesis is upregulated in endocrine cells but not neurons to compensate for the processing defect. These results demonstrate that the CPE mutation differentially affects CCK processing in these two cell types. Intestinal CCK synthesis more closely resembles progastrin processing, suggesting the presence of an endocrine-specific biosynthetic regulatory mechanism not present in neurons.
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Carboxipeptidases/deficiência , Carboxipeptidases/genética , Colecistocinina/metabolismo , Células Enteroendócrinas/metabolismo , Neurônios/metabolismo , Precursores de Proteínas/metabolismo , Animais , Encéfalo/metabolismo , Carboxipeptidase H , Carboxipeptidases/metabolismo , Colecistocinina/sangue , Colecistocinina/genética , Heterozigoto , Camundongos , Camundongos Mutantes , Obesidade/genética , Processamento de Proteína Pós-TraducionalRESUMO
The mouse gastrin gene has three exons totalling 460 bp and a deduced preprogastrin of 101 amino acids. The sequence of murine gastrin-34 is 94% identical to rat gastrin-34 and 76% identical to human gastrin-34. At Arg79, mouse progastrin has a unique cleavage site that might allow species-specific synthesis of gastrin-13. Northern analysis and RT-PCR demonstrated that gastrin gene transcripts are abundant in mouse stomach and duodenum and present at low levels in brain, ovary and pancreas, similar to the pattern described for other mammals. The gastrin gene was mapped to the distal region of mouse chromosome 11.
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Mapeamento Cromossômico , Gastrinas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar , Expressão Gênica , Humanos , Camundongos , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Transcrição GênicaRESUMO
Studies of transgenic mice have shown that transcriptional control of the gastrin gene exhibits significant species differences. Transfection of the human gastrin promoter in murine cells have depicted proximal Sp1, E-box and CACC elements as the major determinants of transcription. We have examined cis-regulatory elements of the human promoter on a human gastrin expressing cell line and find that a distal -135 to -142 Sp1 element is necessary for maximal activity. Alignment of the mouse and human promoters shows that the proximal human Sp1 and CACC elements are not conserved, whereas the E-box element is retained. The distal Sp1 element is present in mouse but exhibits a C to T transition in the core that is likely to reduce binding affinity of Sp1. We conclude that gastrin gene transcription is regulated by distinct elements in man and rodents.
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Gastrinas/genética , Regiões Promotoras Genéticas/genética , Fator de Transcrição Sp1/metabolismo , Transcrição Gênica/genética , Adenocarcinoma , Animais , Sequência de Bases , Clonagem Molecular , DNA/metabolismo , Humanos , Camundongos , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de DNA , Deleção de Sequência , Neoplasias Gástricas , Células Tumorais CultivadasRESUMO
The maturation of many peptide hormones is attenuated in carboxypeptidase E (CPE)-deficient fat/fat mice, leading to a slowly developing, adult-onset obesity with mild diabetes. To determine the contribution of the hormones generated from the proglucagon precursor to this phenotype, we studied the tissue-specific processing of glucagon and glucagon-like peptide-1 (GLP-1) in these mice. In all tissues examined there was a great reduction in mature amidated GLP-1. Furthermore, a lack of CPE attenuates prohormone convertase processing of proglucagon in both the pancreas and the intestine. These findings suggest that defects in proglucagon processing together with other endocrine malfunctions could contribute to the diabetic and obesity phenotype in fat/fat mice.
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Carboxipeptidases/deficiência , Diabetes Mellitus Experimental/metabolismo , Glucagon/metabolismo , Obesidade/metabolismo , Fragmentos de Peptídeos/metabolismo , Precursores de Proteínas/metabolismo , Animais , Carboxipeptidase H , Carboxipeptidases/fisiologia , Cromatografia em Gel , Diabetes Mellitus Experimental/enzimologia , Furina , Peptídeo 1 Semelhante ao Glucagon , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Mutantes , Obesidade/enzimologia , Pâncreas/metabolismo , Proglucagon , Subtilisinas/fisiologia , Extratos de Tecidos/metabolismoRESUMO
The gastric hormone gastrin was first recognized for its ability to induce acid secretion. Following the purification and subsequent development of specific radioimmunoassays for gastrin, it was also shown to be a regulator of oxyntic mucosal growth. To examine the importance of gastrin or its receptors during development in general and for gastric physiology specifically both have been knocked out. Gastrin and gastrin receptor knockout mice are viable, develop without any gross abnormalities, and are fertile. Even though gastrin acts as a growth factor during hypergastrinemia there was no general atrophy of the gastric mucosa in the knockout mice. However, the maturation of both parietal and ECL cells was disturbed and the number of parietal cells was reduced. Basal acid secretion was impaired and rendered the parietal cells unresponsive to secretagogues. Outside the stomach the mice had no apparent phenotype. However, studies have suggested that progastrin and glycine-extended proforms of gastrin may have biological importance, but these results are still circumstantial and identification of the implicated receptors will be crucial for further studies.
Assuntos
Gastrinas/deficiência , Gastrinas/genética , Receptores da Colecistocinina/deficiência , Receptores da Colecistocinina/genética , Animais , Colecistocinina/deficiência , Colecistocinina/genética , Colecistocinina/fisiologia , Neoplasias Colorretais/etiologia , Mucosa Gástrica/crescimento & desenvolvimento , Mucosa Gástrica/fisiologia , Gastrinas/fisiologia , Expressão Gênica , Camundongos , Camundongos Knockout , Fenótipo , Receptores da Colecistocinina/fisiologiaRESUMO
Autoantibodies towards coagulation factor VIII is a rare disease, incidence 1 pr. 2.5-5 million/year. The symptoms are most often subcutaneous or intramuscular haemorrhages or uncontrollable bleeding after minimal traumas. Screening tests show prolonged activated partial thromboplastin time, normal prothrombin time and thrombocyte count. Production of autoantibodies is controlled by prednisolone which may be supplemented with chemotherapy, i.e. azathioprine. Bleeding can be controlled by using coagulation factor concentrates that bypass factor VIII. If diagnosed early, there is a good chance of both stopping bleeding and suppressing autoantibody production. In order to be able to detect patients at risk of having factor VIII autoantibodies, it is recommended to screen all bleeding patients using activated partial thromboplastin time, prothrombin time and thrombocyte count. All patients showing isolated prolonged activated partial thrombin time should be referred to a laboratory specialized in coagulation problems for immediate evaluation.
Assuntos
Autoanticorpos , Transtornos da Coagulação Sanguínea/imunologia , Fator VIII/imunologia , Autoanticorpos/análise , Autoanticorpos/biossíntese , Transtornos da Coagulação Sanguínea/diagnóstico , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Hemorragia/diagnóstico , Hemorragia/tratamento farmacológico , Hemorragia/imunologia , HumanosRESUMO
An East Danish population of acquired haemophilia A (factor VIII inhibitors) patients are described in a retrospective survey. Fifteen patients attended the centre during the period 1981-1994. The epidemiology, clinical presentation, time from début until diagnosis and response to treatment are presented. Acquired factor VIII inhibitors are rare and without treatment the disease has a high mortality and morbidity. Inhibitors mostly develop among the elderly, independent of sex and almost half have no known underlying disease. When the diagnosis is clear, bleedings may be controlled and the patient may be cured by treatment that eliminates the inhibitor. Time until diagnosis varies a lot, for some patients it takes years. It is therefore important to be aware of the disease, so that time with risk of fatal bleeding is shortened as much as possible.
Assuntos
Hemofilia A/etiologia , Adulto , Idoso , Dinamarca/epidemiologia , Diagnóstico Diferencial , Feminino , Hemofilia A/diagnóstico , Hemofilia A/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
CONTEXT: Multiple endocrine neoplasia (MEN-1) is a rare, autosomal dominant inherited disorder. Primary hyperparathyroidism (pHPT) is the most frequent and usually the earliest expression of MEN-1, with typical age of onset at 20-25 years. Early detection of the disease and correct treatment are therefore of great importance. CASE PRESENTATION: A 31-year-old woman with osteogenesis imperfecta was incidentally found also to have hypercalcemia and elevated PTH (pHPT). Exploratory neck surgery showed multiglandular parathyroid affection; she turned out to have MEN-1, but she was diagnosed 7 years after her debut of pHPT. OBJECTIVE AND METHODS: The aim was to search literature on indications for performing mutational analysis in young patients with pHPT and no family history of MEN-1. PubMed was searched for English language articles, and words used were: MEN1 OR MEN-1 OR MEN type 1 OR multiple endocrine neoplasia 1 OR multiple endocrine neoplasia type 1 AND Mutational analysis OR genetic testing OR testing OR Hyperparathyroidism, primary [majr]. A total of 625 abstracts were reviewed. RESULTS AND DISCUSSION: Whether to perform screening of patients with pHPT under the age of 30, 35, or 40 years is controversial. According to international guidelines from 2001, genetic testing is indicated only in patients with pHPT below the age of 30 years. However, in updated guidelines from 2012, it is suggested to perform genetic testing in patients with pHPT below the age of 30 years, but also at any age in patients presenting with multigland parathyroid disease. CONCLUSIONS: The reviewed literature and the presented case illustrate the importance of this change in international guidelines, but they also raise concern for a potential underdiagnosing of patients before year 2012.