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1.
Antioxidants (Basel) ; 10(11)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34829689

RESUMO

Iron is an essential co-factor for many cellular metabolic processes, and mitochondria are main sites of utilization. Iron accumulation promotes production of reactive oxygen species (ROS) via the catalytic activity of iron species. Herein, we investigated the consequences of dietary and genetic iron overload on mitochondrial function. C57BL/6N wildtype and Hfe-/- mice, the latter a genetic hemochromatosis model, received either normal diet (ND) or high iron diet (HI) for two weeks. Liver mitochondrial respiration was measured using high-resolution respirometry along with analysis of expression of specific proteins and ROS production. HI promoted tissue iron accumulation and slightly affected mitochondrial function in wildtype mice. Hepatic mitochondrial function was impaired in Hfe-/- mice on ND and HI. Compared to wildtype mice, Hfe-/- mice on ND showed increased mitochondrial respiratory capacity. Hfe-/- mice on HI showed very high liver iron levels, decreased mitochondrial respiratory capacity and increased ROS production associated with reduced mitochondrial aconitase activity. Although Hfe-/- resulted in increased mitochondrial iron loading, the concentration of metabolically reactive cytoplasmic iron and mitochondrial density remained unchanged. Our data show multiple effects of dietary and genetic iron loading on mitochondrial function and linked metabolic pathways, providing an explanation for fatigue in iron-overloaded hemochromatosis patients, and suggests iron reduction therapy for improvement of mitochondrial function.

2.
Cancer Med ; 10(21): 7747-7758, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34569185

RESUMO

BACKGROUND: Women with Li-Fraumeni syndrome (LFS) have elevated breast cancer (BC) risk. Optimal BC treatment strategies in this population are yet unknown. METHODS: BC subtypes and treatment were retrospectively investigated between December 2016 and January 2019 in a multicentre study. BC risks were evaluated according to the type of surgery. RESULTS: Thirty-five women of our study population (35/44; 79.5%) had developed 36 breast lesions at first diagnosis at a mean age of 34 years. Those breast lesions comprised 32 invasive BCs (89%), three ductal carcinoma in situ alone (8%) and one malignant phyllodes tumour (3%). BCs were mainly high-grade (18/32), of no special type (NST; 31/32), HER2-enriched (11/32) or luminal-B-(like)-type (10/32). Affected women (n = 35) received breast-conserving surgery (BCS, n = 17) or a mastectomy (ME, n = 18) including seven women with simultaneous contralateral prophylactic mastectomy (CPM) at first diagnosis. Nineteen women suffered 20 breast or locoregional axillary lesions at second diagnosis with mean age of 36. Median time between first and second diagnosis was 57 months; median time to contra- and ipsilateral recurrence depended on surgical strategies (BCS: 46 vs. unilateral ME: 93 vs. bilateral ME > 140 months). Women with a primary treatment of solitaire therapeutic ME suffered from contralateral BC earlier compared to those with therapeutic ME and CPM (median: 93 vs. >140 months). CONCLUSION: Aggressive BC subtypes occur among women with LFS. Surgical treatment, i.e. ME and CPM, may prolong time to a second BC diagnosis. Conclusion on long-term survival benefit is pending. Individual competing tumour risks and long-term outcomes need to be taken into consideration.

3.
Cells ; 10(7)2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34359992

RESUMO

Arginase 1 (ARG1) is a cytosolic enzyme that cleaves L-arginine, the substrate of inducible nitric oxide synthase (iNOS), and thereby impairs the control of various intracellular pathogens. Herein, we investigated the role of ARG1 during infection with Salmonella enterica serovar Typhimurium (S.tm). To study the impact of ARG1 on Salmonella infections in vitro, bone marrow-derived macrophages (BMDM) from C57BL/6N wild-type, ARG1-deficient Tie2Cre+/-ARG1fl/fl and NRAMPG169 C57BL/6N mice were infected with S.tm. In wild-type BMDM, ARG1 was induced by S.tm and further upregulated by the addition of interleukin (IL)-4, whereas interferon-γ had an inhibitory effect. Deletion of ARG1 did not result in a reduction in bacterial numbers. In vivo, Arg1 mRNA was upregulated in the spleen, but not in the liver of C57BL/6N mice following intraperitoneal S.tm infection. The genetic deletion of ARG1 (Tie2Cre+/-ARG1fl/fl) or its pharmacological inhibition with CB-1158 neither affected the numbers of S.tm in spleen, liver and blood nor the expression of host response genes such as iNOS, IL-6 or tumour necrosis factor (TNF). Furthermore, ARG1 was dispensable for pathogen control irrespective of the presence or absence of the phagolysosomal natural resistance-associated macrophage protein 1 (NRAMP1). Thus, unlike the detrimental function of ARG1 seen during infections with other intraphagosomal microorganisms, ARG1 did not support bacterial survival in systemic salmonellosis, indicating differential roles of arginine metabolism for host immune response and microbe persistence depending on the type of pathogen.


Assuntos
Arginase/metabolismo , Citocinas/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiologia , Salmonelose Animal/enzimologia , Salmonella typhimurium/fisiologia , Animais , Células da Medula Óssea/microbiologia , Proteínas de Transporte de Cátions , Integrases/metabolismo , Interleucina-4/metabolismo , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pirrolidinas/farmacologia , Regulação para Cima
4.
Respiration ; 100(5): 369-378, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33765679

RESUMO

BACKGROUND: Pulmonary arterial compliance (PAC) is a prognostic parameter in pulmonary arterial hypertension (PAH) reflecting the elasticity of the pulmonary vessels. OBJECTIVES: The objective of this post hoc analysis of a prospective randomized controlled trial (RCT) was to assess the effect of exercise training on PAC and stroke volume (SV) in patients with PAH and persistent/inoperable chronic thromboembolic pulmonary hypertension (CTEPH). METHOD: From the previous RCT, 43 out of 87 patients with severe PAH (n = 29) and CTEPH (n = 14) had complete haemodynamic examinations at baseline and after 15 weeks by right heart catheterization and were analysed (53% female, 79% World Health Organization functional class III/IV, 58% combination therapy, 42% on supplemental oxygen therapy, training group n = 24, and control group n = 19). Medication remained unchanged for all patients. RESULTS: Low-dose exercise training at 4-7 days/week significantly improved PAC (training group 0.33 ± 0.65 mL/mm Hg vs. control group -0.06 ± 1.10 mL/mm Hg; mean difference 0.39 mL/mm Hg, 95% confidence interval [CI] 0.15-0.94 mL/mm Hg; p = 0.004) and SV (training group 9.9 ± 13.4 mL/min vs. control group -4.2 ± 11.0 mL/min; mean difference 14.2 mL, 95% CI 6.5-21.8 mL; p < 0.001) in the training versus control group. Furthermore, exercise training significantly improved cardiac output and pulmonary vascular resistance at rest, peak oxygen consumption, and oxygen pulse. CONCLUSIONS: Our findings suggest that supervised exercise training may improve right ventricular function and PAC at the same time. Further prospective studies are needed to evaluate these findings.

5.
JCI Insight ; 6(8)2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33764904

RESUMO

BACKGROUNDPancreatic cancer is one of the deadliest cancers, with low long-term survival rates. Despite recent advances in treatment, it is important to identify and screen high-risk individuals for cancer prevention. Familial pancreatic cancer (FPC) accounts for 4%-10% of pancreatic cancers. Several germline mutations are related to an increased risk and might offer screening and therapy options. In this study, we aimed to identity of a susceptibility gene in a family with FPC.METHODSWhole exome sequencing and PCR confirmation was performed on the surgical specimen and peripheral blood of an index patient and her sister in a family with high incidence of pancreatic cancer, to identify somatic and germline mutations associated with familial pancreatic cancer. Compartment-specific gene expression data and immunohistochemistry were also queried.RESULTSThe identical germline mutation of the PALLD gene (NM_001166108.1:c.G154A:p.D52N) was detected in the index patient with pancreatic cancer and the tumor tissue of her sister. Whole genome sequencing showed similar somatic mutation patterns between the 2 sisters. Apart from the PALLD mutation, commonly mutated genes that characterize pancreatic ductal adenocarcinoma were found in both tumor samples. However, the 2 patients harbored different somatic KRAS mutations (G12D and G12V). Healthy siblings did not have the PALLD mutation, indicating a disease-specific impact. Compartment-specific gene expression data and IHC showed expression in cancer-associated fibroblasts (CAFs).CONCLUSIONWe identified a germline mutation of the palladin (PALLD) gene in 2 siblings in Europe, affected by familial pancreatic cancer, with a significant overexpression in CAFs, suggesting that stromal palladin could play a role in the development, maintenance, and/or progression of pancreatic cancer.FUNDINGDFG SFB 1321.

6.
Hepatology ; 73(5): 1783-1796, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32893372

RESUMO

BACKGROUND AND AIMS: Gallbladder cancer (GBC) is a neglected disease with substantial geographical variability: Chile shows the highest incidence worldwide, while GBC is relatively rare in Europe. Here, we investigate the causal effects of risk factors considered in current GBC prevention programs as well as C-reactive protein (CRP) level as a marker of chronic inflammation. APPROACH AND RESULTS: We applied two-sample Mendelian randomization (MR) using publicly available data and our own data from a retrospective Chilean and a prospective European study. Causality was assessed by inverse variance weighted (IVW), MR-Egger regression, and weighted median estimates complemented with sensitivity analyses on potential heterogeneity and pleiotropy, two-step MR, and mediation analysis. We found evidence for a causal effect of gallstone disease on GBC risk in Chileans (P = 9 × 10-5 ) and Europeans (P = 9 × 10-5 ). A genetically elevated body mass index (BMI) increased GBC risk in Chileans (P = 0.03), while higher CRP concentrations increased GBC risk in Europeans (P = 4.1 × 10-6 ). European results suggest causal effects of BMI on gallstone disease (P = 0.008); public Chilean data were not, however, available to enable assessment of the mediation effects among causal GBC risk factors. CONCLUSIONS: Two risk factors considered in the current Chilean program for GBC prevention are causally linked to GBC risk: gallstones and BMI. For Europeans, BMI showed a causal effect on gallstone risk, which was itself causally linked to GBC risk.

7.
Z Kinder Jugendpsychiatr Psychother ; 48(6): 478-489, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33172359

RESUMO

Objective: Developmental dyslexia is a highly heritable specific reading and writing disability. To identify a possible new locus and candidate gene for this disability, we investigated a four-generation pedigree where transmission of dyslexia is consistent with an autosomal dominant inheritance pattern. Methods: We performed genome wide array-based SNP genotyping and parametric linkage analysis and sequencing analysis of protein-coding exons, exon-intron boundaries and conserved extragenic regions within the haplotype cosegregating with dyslexia in DNA from one affected and one unaffected family member. Cosegregation was confirmed by sequencing all available family members. Additionally, we analyzed 96 dyslexic individuals who had previously shown positive LOD scores on chromosome 4q28 as well as an even larger sample (n = 2591). Results: We found a single prominent linkage interval on chromosome 4q, where sequence analysis revealed a nucleotide variant in the 3' UTR of brain expressed SPRY1 in the dyslexic family member that cosegregated with dyslexia. This sequence alteration might affect the binding efficiency of the IGF2BP1 RNA-binding protein and thus influence the expression level of the SPRY1 gene product. An analysis of 96 individuals from a cohort of dyslexic individuals revealed a second heterozygous variant in this gene, which was absent in the unaffected sister of the proband. An investigation of the region in a much larger sample further found a nominal p-value of 0.0016 for verbal short-term memory (digit span) in 2,591 individuals for a neighboring SNV. After correcting for the local number of analyzed SNVs, and after taking into account linkage disequilibrium, we found this corresponds to a p-value of 0.0678 for this phenotype. Conclusions: We describe a new locus for familial dyslexia and discuss the possibility that SPRY1 might play a role in the etiology of a monogenic form of dyslexia.


Assuntos
Cromossomos Humanos Par 4/genética , Dislexia/genética , Regiões 3' não Traduzidas/genética , Saúde da Família , Humanos , Escore Lod , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Linhagem , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo
8.
Genes (Basel) ; 11(10)2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33036198

RESUMO

Pathogenic variants have been identified in 85% of heritable pulmonary arterial hypertension (PAH) patients. These variants were mainly located in the bone morphogenetic protein receptor 2 (BMPR2) gene. However, the penetrance of BMPR2 variants was reduced leading to a disease manifestation in only 30% of carriers. In these PAH patients, further modifiers such as additional pathogenic BMPR2 promoter variants could contribute to disease manifestation. Therefore, the aim of this study was to identify BMPR2 promoter variants in PAH patients and to analyze their transcriptional effect on gene expression and disease manifestation. BMPR2 promoter variants were identified in PAH patients and cloned into plasmids. These were transfected into human pulmonary artery smooth muscle cells to determine their respective transcriptional activity. Nine different BMPR2 promoter variants were identified in seven PAH families and three idiopathic PAH patients. Seven of the variants (c.-575A>T, c.-586dupT, c.-910C>T, c.-930_-928dupGGC, c.-933_-928dupGGCGGC, c.-930_-928delGGC and c.-1141C>T) led to a significantly decreased transcriptional activity. This study identified novel BMPR2 promoter variants which may affect BMPR2 gene expression in PAH patients. They could contribute to disease manifestations at least in some families. Further studies are needed to investigate the frequency of BMPR2 promoter variants and their impact on penetrance and disease manifestation.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Regulação da Expressão Gênica , Predisposição Genética para Doença , Mutação , Regiões Promotoras Genéticas , Hipertensão Arterial Pulmonar/patologia , Adulto , Feminino , Humanos , Masculino , Penetrância , Hipertensão Arterial Pulmonar/genética , Estudos Retrospectivos
9.
Cancer Manag Res ; 12: 5077-5084, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636673

RESUMO

Background/Aim: Up to 30% of all patients will present with an advanced or a metastatic stage (mUCC) at the moment of the initial diagnosis of urothelial cell carcinoma of the bladder (UCC). We investigated the numbers, the efficacy and toxicity of different chemotherapies for mUCC in daily practice and "real-life" conditions and evaluated them substance-specifically. Patients and Methods: All patients with a mUCC, who were treated between January 1, 2006 and October 31, 2016 at the Department of Urology and Pediatric Urology at University Hospital Marburg (Germany), were retrospectively analyzed. We set the focus on demographic and tumor-specific data as well as on effectiveness, therapy sequences, and drug tolerance. Results: Forty-one patients were identified. Of the 41 patients, 85.4% of the patients in first-line therapy received gemcitabine/cisplatin. A large proportion of 85.4% received a second-line therapy and 40% a third-line therapy due to progress or relapse. Median overall survival (mOS) was 18 months including all patients and increased up to 29.5 months in the cases of three therapy lines. Conclusion: Our data reveal that chemotherapy of mUCC is effective and side effects are manageable in daily clinical practice.

10.
Cancer ; 126(17): 4032-4041, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32557628

RESUMO

BACKGROUND: Li-Fraumeni syndrome (LFS) is a high-risk cancer predisposition syndrome caused by pathogenic germline variants of TP53. Cancer surveillance has noted a significant survival advantage in individuals with LFS; however, little is known about the feasibility, acceptance, and psychosocial effects of such a program. METHODS: Pathogenic TP53 germline variant carriers completed a 7-part questionnaire evaluating sociodemographics, cancer history, surveillance participation, reasons for nonadherence, worries, and distress adapted from the Cancer Worry Scale. Counselees' common concerns and suggestions were assessed in MAXQDA Analytics Pro 12. RESULTS: Forty-nine participants (46 females and 3 males), aged 40.0 ± 12.6 years, formed the study population; 43 (88%) had a personal cancer history (including multiple cancers in 10 [20%]). Forty-three individuals participated (88%) in surveillance during the study or formerly. Willingness to undergo surveillance was influenced by satisfaction with genetic testing and counseling (P = .019 [Fisher-Yates test]) but not by sociodemographics, cancer history, or distress level. Almost one-third of the participants reported logistical difficulties in implementing surveillance because of the high frequency of medical visits, scheduling difficulties, and the travel distance to their surveillance providers. Self-reported distress and perceived emotional burden for family members and partners were moderate (median for self-reported distress, 3.3; median for perceived emotional burden, 3.0). For both, the interquartile range was moderate to very high (2.7-3.7 and 3.0-3.7, respectively). CONCLUSIONS: Individuals with LFS require efficient counseling as well as an accessible, well-organized, interdisciplinary, standardized surveillance program to increase adherence and psychological coping.


Assuntos
Predisposição Genética para Doença , Síndrome de Li-Fraumeni/genética , Neoplasias/genética , Proteína Supressora de Tumor p53/genética , Adulto , Feminino , Testes Genéticos , Mutação em Linhagem Germinativa/genética , Alemanha/epidemiologia , Heterozigoto , Humanos , Síndrome de Li-Fraumeni/complicações , Síndrome de Li-Fraumeni/epidemiologia , Síndrome de Li-Fraumeni/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/epidemiologia , Neoplasias/patologia , Adulto Jovem
11.
Int J Mol Sci ; 21(9)2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32397294

RESUMO

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare disease which is often caused by recurrent emboli. These are also frequently found in patients with myeloproliferative diseases. While myeloproliferative diseases can be caused by gene defects, the genetic predisposition to CTEPH is largely unexplored. Therefore, the objective of this study was to analyse these genes and further genes involved in pulmonary hypertension in CTEPH patients. A systematic screening was conducted for pathogenic variants using a gene panel based on next generation sequencing. CTEPH was diagnosed according to current guidelines. In this study, out of 40 CTEPH patients 4 (10%) carried pathogenic variants. One patient had a nonsense variant (c.2071A>T p.Lys691*) in the BMPR2 gene and three further patients carried the same pathogenic variant (missense variant, c.1849G>T p.Val617Phe) in the Janus kinase 2 (JAK2) gene. The latter led to a myeloproliferative disease in each patient. The prevalence of this JAK2 variant was significantly higher than expected (p < 0.0001). CTEPH patients may have a genetic predisposition more often than previously thought. The predisposition for myeloproliferative diseases could be an additional risk factor for CTEPH development. Thus, clinical screening for myeloproliferative diseases and genetic testing may be considered also for CTEPH patients.


Assuntos
Predisposição Genética para Doença , Hipertensão Pulmonar/genética , Janus Quinase 2/genética , Transtornos Mieloproliferativos/genética , Embolia Pulmonar/genética , Idoso , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/sangue , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Doença Crônica , Códon sem Sentido , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hipertensão Pulmonar/sangue , Hipertensão Pulmonar/fisiopatologia , Janus Quinase 2/sangue , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Embolia Pulmonar/sangue , Embolia Pulmonar/fisiopatologia , Fatores de Risco
12.
Eur Heart J ; 41(40): 3949-3959, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-32227235

RESUMO

AIMS: Imbalances of iron metabolism have been linked to the development of atherosclerosis. However, subjects with hereditary haemochromatosis have a lower prevalence of cardiovascular disease. The aim of our study was to understand the underlying mechanisms by combining data from genome-wide association study analyses in humans, CRISPR/Cas9 genome editing, and loss-of-function studies in mice. METHODS AND RESULTS: Our analysis of the Global Lipids Genetics Consortium (GLGC) dataset revealed that single nucleotide polymorphisms (SNPs) in the haemochromatosis gene HFE associate with reduced low-density lipoprotein cholesterol (LDL-C) in human plasma. The LDL-C lowering effect could be phenocopied in dyslipidaemic ApoE-/- mice lacking Hfe, which translated into reduced atherosclerosis burden. Mechanistically, we identified HFE as a negative regulator of LDL receptor expression in hepatocytes. Moreover, we uncovered liver-resident Kupffer cells (KCs) as central players in cholesterol homeostasis as they were found to acquire and transfer LDL-derived cholesterol to hepatocytes in an Abca1-dependent fashion, which is controlled by iron availability. CONCLUSION: Our results disentangle novel regulatory interactions between iron metabolism, KC biology and cholesterol homeostasis which are promising targets for treating dyslipidaemia but also provide a mechanistic explanation for reduced cardiovascular morbidity in subjects with haemochromatosis.


Assuntos
Aterosclerose , Proteína da Hemocromatose , Hemocromatose , Animais , Aterosclerose/genética , LDL-Colesterol , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Estudo de Associação Genômica Ampla , Hemocromatose/genética , Homeostase , Humanos , Macrófagos do Fígado , Camundongos , Receptores de LDL
13.
Cancer Epidemiol ; 65: 101643, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32058310

RESUMO

BACKGROUND: The first large-scale genome-wide association study of gallbladder cancer (GBC) recently identified and validated three susceptibility variants in the ABCB1 and ABCB4 genes for individuals of Indian descent. We investigated whether these variants were also associated with GBC risk in Chileans, who show the highest incidence of GBC worldwide, and in Europeans with a low GBC incidence. METHODS: This population-based study analysed genotype data from retrospective Chilean case-control (255 cases, 2042 controls) and prospective European cohort (108 cases, 181 controls) samples consistently with the original publication. RESULTS: Our results confirmed the reported associations for Chileans with similar risk effects. Particularly strong associations (per-allele odds ratios close to 2) were observed for Chileans with high Native American (=Mapuche) ancestry. No associations were noticed for Europeans, but the statistical power was low. CONCLUSION: Taking full advantage of genetic and ethnic differences in GBC risk may improve the efficiency of current prevention programs.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Neoplasias da Vesícula Biliar/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Chile/epidemiologia , Europa (Continente)/epidemiologia , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Neoplasias da Vesícula Biliar/epidemiologia , Estudos de Associação Genética , Humanos , Índios Sul-Americanos/genética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos
14.
Am J Pathol ; 190(3): 702-710, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31953036

RESUMO

Papillary thyroid carcinomas (PTCs) account for 90% of human thyroid cancer cases, which represent 1% of all cancer cases. They are likely to develop from papillary thyroid microcarcinomas (PTMCs), found in up to 36% of healthy individuals, due to rare progression events (0.01%). Although the prognosis of PTCs is excellent, 5% to 10% of tumors display an unfavorable outcome. About 45% of PTCs exhibit activating BRAFV600E mutations. Rats of the inbred BD strains postnatally exposed to the carcinogen N-ethyl-N-nitrosourea developed PTMCs, which closely resembled their human counterparts judging from their histology, size, and marginal tendency to progress. DNA sequencing revealed mutations in exon 15 of the Braf gene identical to the human BRAFV600E mutation in 82% of the cases. Predominantly a 50:50 ratio of wild-type to mutant Braf alleles was seen regardless of tumor size or animal age, indicating that the Braf mutation is an early, if not the initial, event in rat PTMC development. Surprisingly, most PTMCs carrying a confirmed BrafV600E mutation did not display BrafV600E protein expression. As the BrafV600Egene is supposed to be the driver in PTC development, down-regulation of expression should contribute to the low risk for progression of PTMC. This model system will enable further insights into the molecular mechanisms of PTMC initiation and progression to PTC, further translating into targeted tumor prevention strategies/therapies.


Assuntos
Carcinoma Papilar/patologia , Etilnitrosoureia/efeitos adversos , Proteínas Proto-Oncogênicas B-raf/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Alelos , Substituição de Aminoácidos , Animais , Modelos Animais de Doenças , Éxons/genética , Feminino , Humanos , Imuno-Histoquímica , Masculino , Mutação , Prognóstico , Ratos , Análise de Sequência de DNA , Câncer Papilífero da Tireoide/induzido quimicamente , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/induzido quimicamente , Neoplasias da Glândula Tireoide/patologia
15.
High Alt Med Biol ; 21(1): 28-36, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31976756

RESUMO

Background: Exaggerated pulmonary arterial hypertension (PAH) is a hallmark of high-altitude pulmonary edema (HAPE). The objective of this study was therefore to investigate genetic predisposition to HAPE by analyzing PAH candidate genes in a HAPE-susceptible (HAPE-S) family and in unrelated HAPE-S mountaineers. Materials and Methods: Eight family members and 64 mountaineers were clinically and genetically assessed using a PAH-specific gene panel for 42 genes by next-generation sequencing. Results: Two otherwise healthy family members, who developed re-entry HAPE at 3640 m during childhood, carried a likely pathogenic missense mutation (c.1198T>G p.Cys400Gly) in the Janus Kinase 2 (JAK2) gene. One of them progressed to a mild form of PAH at the age of 23 years. In two of the 64 HAPE-S mountaineers likely pathogenic variants have been detected, one missense mutation in the Cytochrome P1B1 gene, and a deletion in the Histidine-Rich Glycoprotein (HRG) gene. Conclusions: This is the first study identifying an inherited missense mutation of a gene related to PAH in a family with re-entry HAPE showing a progression to borderline PAH in the index patient. Likely pathogenic variants in 3.1% of HAPE-S mountaineers suggest a genetic predisposition in some individuals that might be linked to PAH signaling pathways.


Assuntos
Doença da Altitude , Hipertensão Pulmonar , Edema Pulmonar , Adulto , Altitude , Doença da Altitude/genética , Criança , Predisposição Genética para Doença , Humanos , Hipertensão Pulmonar/genética , Edema Pulmonar/genética , Adulto Jovem
16.
Int J Cancer ; 146(4): 999-1009, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31081934

RESUMO

Comparably little is known about breast cancer (BC) risks in women from families tested negative for BRCA1/2 mutations despite an indicative family history, as opposed to BRCA1/2 mutation carriers. We determined the age-dependent risks of first and contralateral breast cancer (FBC, CBC) both in noncarriers and carriers of BRCA1/2 mutations, who participated in an intensified breast imaging surveillance program. The study was conducted between January 1, 2005, and September 30, 2017, at 12 university centers of the German Consortium for Hereditary Breast and Ovarian Cancer. Two cohorts were prospectively followed up for incident FBC (n = 4,380; 16,398 person-years [PY], median baseline age: 39 years) and CBC (n = 2,993; 10,090 PY, median baseline age: 42 years). Cumulative FBC risk at age 60 was 61.8% (95% CI 52.8-70.9%) for BRCA1 mutation carriers, 43.2% (95% CI 32.1-56.3%) for BRCA2 mutation carriers and 15.7% (95% CI 11.9-20.4%) for noncarriers. FBC risks were significantly higher than in the general population, with incidence rate ratios of 23.9 (95% CI 18.9-29.8) for BRCA1 mutation carriers, 13.5 (95% CI 9.2-19.1) for BRCA2 mutation carriers and 4.9 (95% CI 3.8-6.3) for BRCA1/2 noncarriers. Cumulative CBC risk 10 years after FBC was 25.1% (95% CI 19.6-31.9%) for BRCA1 mutation carriers, 6.6% (95% CI 3.4-12.5%) for BRCA2 mutation carriers and 3.6% (95% CI 2.2-5.7%) for noncarriers. CBC risk in noncarriers was similar to women with unilateral BC from the general population. Further studies are needed to confirm whether less intensified surveillance is justified in women from BRCA1/2 negative families with elevated risk.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/epidemiologia , Predisposição Genética para Doença , Adulto , Fatores Etários , Neoplasias da Mama/genética , Monitoramento Epidemiológico , Feminino , Seguimentos , Alemanha/epidemiologia , Heterozigoto , Humanos , Incidência , Anamnese , Pessoa de Meia-Idade , Mutação , Estudos Prospectivos , Medição de Risco , Fatores de Risco
17.
Arthritis Res Ther ; 21(1): 217, 2019 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655622

RESUMO

OBJECTIVE: The objective of this randomized, placebo-controlled, double-blind, parallel group, trial was to assess the effect of ambrisentan on mean pulmonary arterial pressure (mPAP) in patients with systemic sclerosis (SSc) and mildly elevated pulmonary hypertension (PH). METHODS: Thirty-eight SSc patients with mildly elevated mPAP at rest between 21 and 24 mmHg and/or > 30 mmHg during low-dose exercise were randomly assigned to treatment with either ambrisentan 5-10 mg/day or placebo. Right heart catheterization and further clinical parameters were assessed at baseline and after 6 months. The primary endpoint was the difference of mPAP change at rest between groups. RESULTS: After 6 months, the two groups did not differ in the primary endpoint (ambrisentan mPAP - 1 ± 6.4 mmHg vs. placebo - 0.73 ± 3.59 mmHg at rest, p = 0.884). However, three patients from the placebo group but none of the ambrisentan group progressed to SSc-associated pulmonary arterial hypertension. Furthermore, ambrisentan treatment showed significant improvements in the secondary endpoints cardiac index (CI) and pulmonary vascular resistance (PVR) at rest (CI 0.36 ± 0.66 l/min/m2 vs. - 0.31 ± 0.71 l/min/m2, p = 0.010; PVR - 0.70 ± 0.78 WU vs. 0.01 ± 0.71 WU, p = 0.012) and during exercise (CI 0.7 ± 0.81 l/min/m2 vs. - 0.45 ± 1.36 l/min/m2, p = 0.015; PVR - 0.84 ± 0.48 WU vs. - 0.0032 ± 0.34 WU, p < 0.0001). CONCLUSION: This is the first randomized, double-blind, placebo-controlled study testing the effect of ambrisentan in patients with mildly elevated mPAP and/or exercise PH. The primary endpoint change in mPAP did only tendentially improve in the ambrisentan group, but the significant improvement of other hemodynamic parameters points to a possible benefit of ambrisentan and will be helpful to design future trials. TRIAL REGISTRATION: www.ClinicalTrials.gov, unique identifier NCT: NCT02290613 , registered 14th of November 2014.


Assuntos
Anti-Hipertensivos/administração & dosagem , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/epidemiologia , Fenilpropionatos/administração & dosagem , Piridazinas/administração & dosagem , Escleroderma Sistêmico/tratamento farmacológico , Escleroderma Sistêmico/epidemiologia , Idoso , Estudos de Coortes , Método Duplo-Cego , Feminino , Humanos , Hipertensão Pulmonar/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Escleroderma Sistêmico/diagnóstico , Tempo para o Tratamento/tendências
19.
Arthritis Rheumatol ; 71(5): 805-816, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30615302

RESUMO

OBJECTIVE: This prospective study was undertaken to evaluate right ventricular function and pulmonary arterial compliance (PAC; ratio of stroke volume to pulse pressure) at rest and during exercise in patients with systemic sclerosis (SSc) with normal mean pulmonary artery pressure (PAP), patients with SSc with mildly elevated mean PAP, and patients with SSc with manifest pulmonary hypertension (PH). METHODS: Patients with SSc (n = 112) underwent clinical assessment and right-sided heart catheterization at rest and during exercise and were divided into 3 groups according to their resting mean PAP values: normal mean PAP (≤20 mm Hg), mildly elevated mean PAP (21-24 mm Hg), and PH (mean PAP ≥25 mm Hg). Results were compared between groups by analysis of variance followed by post hoc Student's t-test. RESULTS: Compared to patients with normal mean PAP, patients with mildly elevated mean PAP had a lower 6-minute walking distance (P = 0.008), lower cardiac index (P = 0.027) and higher pulmonary vascular resistance (P = 0.0002) during exercise, and lower PAC at rest (P = 0.016) and different stages of exercise (P = 0.033 for 25W and P = 0.024 for 75W). CONCLUSION: The results of this study suggest that impaired 6-minute walking distance in SSc patients with mildly elevated mean PAP might be caused by reduced PAC during exercise and reduced right ventricular output reserve, presumably due to impaired coupling between the right ventricle and the pulmonary vasculature. These findings provide further evidence of the clinical relevance of mildly elevated mean PAP in patients with SSc.


Assuntos
Débito Cardíaco/fisiologia , Hipertensão Arterial Pulmonar/fisiopatologia , Artéria Pulmonar/fisiopatologia , Escleroderma Sistêmico/fisiopatologia , Resistência Vascular/fisiologia , Disfunção Ventricular Direita/fisiopatologia , Adulto , Idoso , Pressão Sanguínea/fisiologia , Cateterismo Cardíaco , Estudos de Casos e Controles , Complacência (Medida de Distensibilidade) , Ecocardiografia Doppler , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico/fisiologia , Disfunção Ventricular Direita/diagnóstico por imagem , Teste de Caminhada
20.
Front Mol Biosci ; 5: 109, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30560135

RESUMO

Intestinal absorption of dietary amino acids is mediated via two routes. Free amino acids released by hydrolysis of dietary proteins are taken up by a multitude of amino acid transporters while di- and tripeptides released are taken up by the peptide transporter PEPT-1. Loss of PEPT-1 impairs growth, post-embryonic development and reproduction in Caenorhabditis elegans, and supplementation with a mixture of all L-amino acids only partially rescues fertility. In the present study, we demonstrate that dietary L-glutamate is the responsible amino acid that can increase fertility in hermaphrodite pept-1 worms. This effect was associated with a significantly higher uptake of glutamate/aspartate in pept-1 than in wildtype C. elegans. Furthermore, we found that the intestinal transporter proteins SNF-5 of the solute carrier SLC6 family of nutrient amino acid transporters (NAT) and AAT-6 of the SLC7 family as the light subunit of a heteromeric amino acid transporter (HAT) play a key role in glutamate homeostasis in pept-1 C. elegans. Genes encoding these transporters are highly expressed and upon silencing a 95% reduced fertility (snf-5) and sterility (aat-6) was observed. A subsequent L-glutamate supplementation failed to rescue these phenotypes. Dietary glutamate supplementation did neither influence the feeding frequency, nor did it improve mating efficiency of pept-1 males. Most strikingly, pept-1 were more prone to habituation to repeated gentle touch stimuli than wildtype C. elegans, and dietary glutamate supply was sufficient to alter this behavioral output by restoring the mechanosensory response to wildtype levels. Taken together, our data demonstrate a key role of L-glutamate in amino acid homeostasis in C. elegans lacking the peptide transporter in the intestine and demonstrate its distinct role in reproduction and for neural circuits mediating touch sensitivity.

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