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The mergers of binary compact objects such as neutron stars and black holes are of central interest to several areas of astrophysics, including as the progenitors of gamma-ray bursts (GRBs)1, sources of high-frequency gravitational waves (GWs)2 and likely production sites for heavy-element nucleosynthesis by means of rapid neutron capture (the r-process)3. Here we present observations of the exceptionally bright GRB 230307A. We show that GRB 230307A belongs to the class of long-duration GRBs associated with compact object mergers4-6 and contains a kilonova similar to AT2017gfo, associated with the GW merger GW170817 (refs. 7-12). We obtained James Webb Space Telescope (JWST) mid-infrared imaging and spectroscopy 29 and 61 days after the burst. The spectroscopy shows an emission line at 2.15 microns, which we interpret as tellurium (atomic mass A = 130) and a very red source, emitting most of its light in the mid-infrared owing to the production of lanthanides. These observations demonstrate that nucleosynthesis in GRBs can create r-process elements across a broad atomic mass range and play a central role in heavy-element nucleosynthesis across the Universe.
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A dichotomous choice for metazoan cells is between proliferation and differentiation. Measuring tRNA pools in various cell types, we found two distinct subsets, one that is induced in proliferating cells, and repressed otherwise, and another with the opposite signature. Correspondingly, we found that genes serving cell-autonomous functions and genes involved in multicellularity obey distinct codon usage. Proliferation-induced and differentiation-induced tRNAs often carry anticodons that correspond to the codons enriched among the cell-autonomous and the multicellularity genes, respectively. Because mRNAs of cell-autonomous genes are induced in proliferation and cancer in particular, the concomitant induction of their codon-enriched tRNAs suggests coordination between transcription and translation. Histone modifications indeed change similarly in the vicinity of cell-autonomous genes and their corresponding tRNAs, and in multicellularity genes and their tRNAs, suggesting the existence of transcriptional programs coordinating tRNA supply and demand. Hence, we describe the existence of two distinct translation programs that operate during proliferation and differentiation.
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Diferenciación Celular , Proliferación Celular , Biosíntesis de Proteínas , ARN de Transferencia/genética , Anticodón , Línea Celular Tumoral , Transformación Celular Neoplásica , Codón , Histonas/metabolismo , Humanos , Neoplasias/genética , ARN Mensajero/metabolismo , ARN de Transferencia/química , ARN de Transferencia/metabolismo , TranscriptomaRESUMEN
BACKGROUND AND AIMS: Hereditary haemorrhagic telangiectasia (HHT) is an autosomal dominant condition characterised by recurrent epistaxis, telangiectatic lesions in the skin and mucosal membranes, and arteriovenous malformations (AVMs) in various organs. In 3%-5% of patients, HHT is caused by pathogenic germline variants (PVs) in SMAD4, and these patients often have additional symptoms of juvenile polyposis syndrome and thoracic aneurysms. The phenotypic spectrum of SMAD4-associated HHT is less known, including the penetrance and severity of HHT. We aimed to investigate the phenotypic spectrum of HHT manifestations in Danish patients with PVs in SMAD4 and compare the findings with current literature. METHODS: The study is a retrospective nationwide study with all known Danish patients with PVs in SMAD4. In total, 35 patients were included. The patients were identified by collecting data from genetic laboratories, various databases and clinical genetic departments across the country. Clinical information was mainly collected from the Danish HHT-Centre at Odense University Hospital. RESULTS: Twenty-nine patients with PVs in SMAD4 (83%) were seen at the HHT-Centre. Seventy-six per cent of these fulfilled the Curaçao criteria, 86% experienced recurrent epistaxis and 83% presented with telangiectatic lesions at different anatomical localisations. Almost 60% had AVMs, mainly pulmonary and hepatic, while none was found to have cerebral AVMs. Fifteen per cent had thoracic aortic abnormalities. CONCLUSION: We present a nationwide study of one of the largest populations of patients with PVs in SMAD4 that has systematically been examined for HHT manifestations. The patients presented the full spectrum of HHT-related manifestations and the majority fulfilled the Curaçao criteria.
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Proteína Smad4 , Telangiectasia Hemorrágica Hereditaria , Humanos , Dinamarca/epidemiología , Epistaxis/etiología , Epistaxis/genética , Malformaciones Arteriovenosas Intracraneales , Mutación , Estudios Retrospectivos , Proteína Smad4/genética , Telangiectasia Hemorrágica Hereditaria/epidemiología , Telangiectasia Hemorrágica Hereditaria/genética , Telangiectasia Hemorrágica Hereditaria/diagnósticoRESUMEN
Peutz-Jeghers syndrome (PJS) is an autosomal dominant hereditary polyposis syndrome causing increased morbidity and mortality due to complications of polyposis and the development of cancer. STK11 is the only gene known to be associated with PJS, although in 10%-15% of patients fulfilling the diagnostic criteria no pathogenic variant (PV) is identified. The primary aim of this study was to identify the genetic etiology in all known PJS patients in Denmark and to estimate the risk of cancer, effect of surveillance and overall survival. We identified 56 patients (2-83 years old) with PJS. The detection rate of PVs was 96%, including three cases of mosaicism (6%). In two patients a variant was not detected. At the age of 40 years, the probabilities of cancer and death were 21% and 16%, respectively; at the age of 70 years these probabilities were 71% and 69%. Most cases of cancer (92%) were identified between the scheduled examinations in the surveillance program. These observations emphasize that PJS should be regarded as a general cancer predisposition syndrome, where improvement of clinical care is needed.
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Neoplasias Colorrectales , Síndrome de Peutz-Jeghers , Humanos , Adulto , Anciano , Preescolar , Niño , Adolescente , Adulto Joven , Persona de Mediana Edad , Anciano de 80 o más Años , Síndrome de Peutz-Jeghers/complicaciones , Síndrome de Peutz-Jeghers/genética , Síndrome de Peutz-Jeghers/diagnóstico , Proteínas Serina-Treonina Quinasas/genética , Genotipo , MosaicismoRESUMEN
Skipping of BRCA2 exon 3 (∆E3) is a naturally occurring splicing event, complicating clinical classification of variants that may alter ∆E3 expression. This study used multiple evidence types to assess pathogenicity of 85 variants in/near BRCA2 exon 3. Bioinformatically predicted spliceogenic variants underwent mRNA splicing analysis using minigenes and/or patient samples. ∆E3 was measured using quantitative analysis. A mouse embryonic stem cell (mESC) based assay was used to determine the impact of 18 variants on mRNA splicing and protein function. For each variant, population frequency, bioinformatic predictions, clinical data, and existing mRNA splicing and functional results were collated. Variant class was assigned using a gene-specific adaptation of ACMG/AMP guidelines, following a recently proposed points-based system. mRNA and mESC analysis combined identified six variants with transcript and/or functional profiles interpreted as loss of function. Cryptic splice site use for acceptor site variants generated a transcript encoding a shorter protein that retains activity. Overall, 69/85 (81%) variants were classified using the points-based approach. Our analysis shows the value of applying gene-specific ACMG/AMP guidelines using a points-based approach and highlights the consideration of cryptic splice site usage to appropriately assign PVS1 code strength.
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Genes BRCA2 , Sitios de Empalme de ARN , Animales , Humanos , Ratones , Empalme Alternativo , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Empalme del ARN , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
The use of the sleep-promoting hormone melatonin is rapidly increasing as an assumed safe sleep aid. During the last decade, accumulating observations suggest that melatonin affects glucose homeostasis, but the precise role remains to be defined. We investigated the metabolic effects of long-term melatonin treatment in patients with type 2 diabetes including determinations of insulin sensitivity and glucose-stimulated insulin secretion. We used a double-blinded, randomized, placebo-controlled, crossover design. Seventeen male participants with type 2 diabetes completed (1) 3 months of daily melatonin treatment (10 mg) 1 h before bedtime (M) and (2) 3 months of placebo treatment 1 h before bedtime (P). At the end of each treatment period, insulin secretion was assessed by an intravenous glucose tolerance test (0.3 g/kg) (IVGTT) and insulin sensitivity was assessed by a hyperinsulinemic-euglycemic clamp (insulin infusion rate 1.5 mU/kg/min) (primary endpoints). Insulin sensitivity decreased after melatonin (3.6 [2.9-4.4] vs. 4.1 [3.2-5.2] mg/(kg × min), p = .016). During the IVGTT, the second-phase insulin response was increased after melatonin (p = .03). In conclusion, melatonin treatment of male patients with type 2 diabetes for 3 months decreased insulin sensitivity by 12%. Clinical use of melatonin treatment in dosages of 10 mg should be reserved for conditions where the benefits will outweigh the potential negative impact on insulin sensitivity.
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Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Melatonina , Glucemia/metabolismo , Estudios Cruzados , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Método Doble Ciego , Glucosa , Humanos , Insulina/metabolismo , Masculino , Melatonina/uso terapéuticoRESUMEN
Candidates for the modest galaxies that formed most of the stars in the early Universe, at redshifts z > 7, have been found in large numbers with extremely deep restframe-ultraviolet imaging. But it has proved difficult for existing spectrographs to characterize them using their ultraviolet light. The detailed properties of these galaxies could be measured from dust and cool gas emission at far-infrared wavelengths if the galaxies have become sufficiently enriched in dust and metals. So far, however, the most distant galaxy discovered via its ultraviolet emission and subsequently detected in dust emission is only at z = 3.2 (ref. 5), and recent results have cast doubt on whether dust and molecules can be found in typical galaxies at z ≥ 7. Here we report thermal dust emission from an archetypal early Universe star-forming galaxy, A1689-zD1. We detect its stellar continuum in spectroscopy and determine its redshift to be z = 7.5 ± 0.2 from a spectroscopic detection of the Lyman-α break. A1689-zD1 is representative of the star-forming population during the epoch of reionization, with a total star-formation rate of about 12 solar masses per year. The galaxy is highly evolved: it has a large stellar mass and is heavily enriched in dust, with a dust-to-gas ratio close to that of the Milky Way. Dusty, evolved galaxies are thus present among the fainter star-forming population at z > 7.
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PURPOSE: We assessed the associations between population-based polygenic risk scores (PRS) for breast (BC) or epithelial ovarian cancer (EOC) with cancer risks for BRCA1 and BRCA2 pathogenic variant carriers. METHODS: Retrospective cohort data on 18,935 BRCA1 and 12,339 BRCA2 female pathogenic variant carriers of European ancestry were available. Three versions of a 313 single-nucleotide polymorphism (SNP) BC PRS were evaluated based on whether they predict overall, estrogen receptor (ER)-negative, or ER-positive BC, and two PRS for overall or high-grade serous EOC. Associations were validated in a prospective cohort. RESULTS: The ER-negative PRS showed the strongest association with BC risk for BRCA1 carriers (hazard ratio [HR] per standard deviation = 1.29 [95% CI 1.25-1.33], P = 3×10-72). For BRCA2, the strongest association was with overall BC PRS (HR = 1.31 [95% CI 1.27-1.36], P = 7×10-50). HR estimates decreased significantly with age and there was evidence for differences in associations by predicted variant effects on protein expression. The HR estimates were smaller than general population estimates. The high-grade serous PRS yielded the strongest associations with EOC risk for BRCA1 (HR = 1.32 [95% CI 1.25-1.40], P = 3×10-22) and BRCA2 (HR = 1.44 [95% CI 1.30-1.60], P = 4×10-12) carriers. The associations in the prospective cohort were similar. CONCLUSION: Population-based PRS are strongly associated with BC and EOC risks for BRCA1/2 carriers and predict substantial absolute risk differences for women at PRS distribution extremes.
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Neoplasias de la Mama , Neoplasias Ováricas , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Carcinoma Epitelial de Ovario/genética , Femenino , Predisposición Genética a la Enfermedad , Heterocigoto , Humanos , Mutación , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/genética , Estudios Prospectivos , Estudios Retrospectivos , Factores de RiesgoRESUMEN
Familial dysautonomia (FD) is a severe genetic disorder causing sensory and autonomic dysfunction. It is predominantly caused by a c.2204+6T>C mutation in the IKBKAP gene. This mutation decreases the 5' splice site strength of IKBKAP exon 20 leading to exon 20 skipping and decreased amounts of full-length IKAP protein. We identified a binding site for the splicing regulatory protein hnRNP A1 downstream of the IKBKAP exon 20 5'-splice site. We show that hnRNP A1 binds to this splicing regulatory element (SRE) and that two previously described inhibitory SREs inside IKBKAP exon 20 are also bound by hnRNP A1. Knockdown of hnRNP A1 in FD patient fibroblasts increases IKBKAP exon 20 inclusion demonstrating that hnRNP A1 is a negative regulator of IKBKAP exon 20 splicing. Furthermore, by mutating the SREs in an IKBKAP minigene we show that all three SREs cause hnRNP A1-mediated exon repression. We designed splice switching oligonucleotides (SSO) that blocks the intronic hnRNP A1 binding site, and demonstrate that this completely rescues splicing of IKBKAP exon 20 in FD patient fibroblasts and increases the amounts of IKAP protein. We propose that this may be developed into a potential new specific treatment of FD.
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Proteínas Portadoras/genética , Ribonucleoproteína Nuclear Heterogénea A1/genética , Mutación , Empalme del ARN , Secuencia de Bases , Sitios de Unión/genética , Proteínas Portadoras/metabolismo , Línea Celular , Células Cultivadas , Exones/genética , Fibroblastos/metabolismo , Ribonucleoproteína Nuclear Heterogénea A1/metabolismo , Humanos , Intrones/genética , Oligonucleótidos/genética , Oligonucleótidos/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos/genética , Factores de Elongación TranscripcionalRESUMEN
The potential endocrine disrupting effects of the commonly prescribed anti-epileptic drug lamotrigine (LAM) were investigated using the H295R steroidogenic in vitro assay and computational chemistry methods. The H295R cells were exposed to different concentrations of LAM, and a multi-steroid LC-MS/MS method was applied to quantify the amount of secreted steroid hormones. LAM affected several steroid hormones in the steroidogenesis at therapeutic concentrations. All progestagens as well as 11-deoxycorticosterone and corticosterone increased 100-200% with increasing concentrations of LAM suggesting a selective inhibitory effect of LAM on CYP17A1, in particular on the lyase reaction. Recombinant CYP17A1 assay confirmed the competitive inhibition of LAM toward the enzyme with IC50 values of 619 and 764 µM for the lyase and the hydroxylase reaction, respectively. Levels of androstenedione and testosterone decreased at LAM concentrations above the therapeutic concentration range. The ability of LAM to bind to CYP17A1, CYP19A1, and CYP21A2 was investigated using docking and molecular dynamics simulations. This in silico study showed that LAM was able to bind directly to the heme iron in the active site of CYP17A1, but not CYP21A2, thus supporting the results of the in vitro studies. The molecular dynamics simulations also suggested binding of LAM to the heme iron in the CYP19A1 active site. No inhibition of the aromatase enzyme was, however, observed in the H295R assay. This could be due to a sequential effect within the steroidogenesis caused by the inhibition of CYP17A1, which reduced the amounts of androgens available for CYP19A1.
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Anticonvulsivantes/farmacología , Inhibidores de la Aromatasa/farmacología , Aromatasa/metabolismo , Lamotrigina/farmacología , Anticonvulsivantes/química , Aromatasa/química , Inhibidores de la Aromatasa/química , Dominio Catalítico , Línea Celular , Disruptores Endocrinos/química , Disruptores Endocrinos/farmacología , Humanos , Técnicas In Vitro , Lamotrigina/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Esteroides/biosíntesisRESUMEN
Increased tendon cell nuclei density (TCND) has been proposed to induce tendon mechanical adaptations. However, it is unknown whether TCND is increased in tendon tissue after mechanical loading and whether such an increase can be quantified in a reliable manner. The aim of this study was to develop a reliable method for quantification of TCND and to investigate potential changes in TCND in rat Achilles tendons in response to 12 weeks of running. Eight adult male Sprague-Dawley rats ran (RUN) on a treadmill with 10° incline, 1 h/day, 5 days/wk (17-20 m/min) for 12 weeks (which improved tendon mechanical properties) and were compared with 11 control rats (SED). Tissue-Tek-embedded cryosections (10 µm) from the mid region of the Achilles tendon were cut longitudinally on a cryostat. Sections were stained with alcian blue and picrosirius red. One blinded investigator counted the number of tendon cell nuclei 2-3 times in three separate regions of the mid longitudinal tendon sections with fields of 390 µm × 280 µm. Unpaired t tests were used for the statistical analysis (mean ± SE). Typical Error % for replicate counts was 5.5 and 14 % coefficient of variation for the three regions. There was no difference in TCND between running rats versus control rats (nuclei per image (≈105 µm2): RUN, 152 ± 9; SED, 146 ± 8, p = 0.642). This new method provided reproducible quantification of TCND. There was no difference in TCND despite improvements in tendon mechanics, which suggests that cell number is not a major cause for altered tendon mechanical properties with loading.
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Tendón Calcáneo/citología , Recuento de Células , Animales , Núcleo Celular , Masculino , Ratas , Ratas Sprague-Dawley , Adhesión del TejidoRESUMEN
INTRODUCTION AND HYPOTHESIS: Alternative approaches to reinforce the native tissue in patients with pelvic organ prolapse (POP) are needed to improve surgical outcome. Our aims were to develop a weakened abdominal wall in a rat model to mimic the weakened vaginal wall in women with POP and then evaluate the regenerative potential of a quickly biodegradable synthetic scaffold, methoxypolyethylene glycol polylactic-co-glycolic acid (MPEG-PLGA), seeded with autologous muscle fiber fragments (MFFs) using this model. METHODS: In an initial pilot study with 15 animals, significant weakening of the abdominal wall and a feasible technique was established by creating a partial defect with removal of one abdominal muscle layer. Subsequently, 18 rats were evenly divided into three groups: (1) unrepaired partial defect; (2) partial defect repaired with MPEG-PLGA; (3) partial defect repaired with MPEG-PLGA and MFFs labeled with PKH26-fluorescence dye. After 8 weeks, we performed histopathological and immunohistochemical testing, fluorescence analysis, and uniaxial biomechanical testing. RESULTS: Both macroscopically and microscopically, the MPEG-PLGA scaffold was fully degraded, with no signs of an inflammatory or foreign-body response. PKH26-positive cells were found in all animals from the group with added MFFs. Analysis of variance (ANOVA) showed a significant difference between groups with respect to load at failure (p = 0.028), and post hoc testing revealed that the group with MPEG-PLGA and MFFs showed a significantly higher strength than the group with MPEG-PLGA alone (p = 0.034). CONCLUSION: Tissue-engineering with MFFs seeded on a scaffold of biodegradable MPEG-PLGA might be an interesting adjunct to future POP repair.
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Pared Abdominal/cirugía , Fibras Musculares Esqueléticas/fisiología , Polietilenglicoles , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Análisis de Varianza , Animales , Materiales Biocompatibles , Portadores de Fármacos , Femenino , Humanos , Modelos Animales , Compuestos Orgánicos , Prolapso de Órgano Pélvico/cirugía , Proyectos Piloto , Distribución Aleatoria , RatasRESUMEN
INTRODUCTION AND HYPOTHESIS: The use of permanent synthetic meshes to improve the outcome of pelvic organ prolapse (POP) repair causes frequent and serious complications. The use of the synthetic, biodegradable scaffold methoxypolyethyleneglycol-polylactic-co-glycolic acid (MPEG-PLGA) seeded with autologous muscle fiber fragments (MFF), as an adjunct to native tissue POP repair, is a potential new alternative. METHODS: A rat abdominal wall model of native repair was used with six animals in each of three groups: native repair, native repair + MPEG-PLGA, and native repair + MPEG-PLGA + MFF. MFF were labeled with PKH26-fluorescence dye. After 8 weeks labeled cells were identified in tissue samples and histopathological and immunohistochemical analyses of connective tissue organization and desmin reactivity of muscle cells were performed. Fresh tissue samples were subjected to uniaxial biomechanical testing. Statistical analyses were performed using one-way analysis of variance (ANOVA). RESULTS: MPEG-PLGA was fully degraded after 8 weeks. Desmin-immunopositive (6/6) and PKH26-positive cells (6/6) were found only after native repair + MPEG-PLGA + MFF, indicating survival, proliferation, and integration of cells originating from the MFF. This group also showed significantly increased stiffness in the high stiffness zone compared with native repair + MPEG-PLGA (p = 0.032) and borderline significantly higher stiffness compared to native repair (p = 0.054). CONCLUSIONS: In this pilot study, MPEG-PLGA scaffolds seeded with autologous MFF affected some histological and biomechanical properties of native tissue repair in an abdominal wall defect model in rats. The method thus appears to be a simple tissue engineering concept with potential relevance for native tissue repair of POP.
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Pared Abdominal/cirugía , Regeneración Tisular Dirigida , Fibras Musculares Esqueléticas/trasplante , Poliésteres , Polietilenglicoles , Andamios del Tejido , Animales , Materiales Biocompatibles , Femenino , Modelos Animales , Ratas , Ratas Sprague-DawleyRESUMEN
BACKGROUND AND PURPOSE: YKL-40 is a glycoprotein that is expressed in many types of cancer cells. In some cancers, there is a correlation between high serum YKL-40 levels on the one hand and more aggressive disease and early death on the other. YKL-40 has never been studied in patients with soft-tissue sarcomas (STSs). We investigated whether YKL-40 is expressed in STS tissue and ascertained that the degree of expression is related to survival and/or the histological grade of the malignancy (FNCLCC). PATIENTS AND METHODS: We included archived tissue from 49 patients (40 with STS and 9 with atypical lipomatous tumor, 20 female and 29 male, mean age 58 (4-89) years) who were treated with tumor resection in 2004 or 2005 at the Department of Orthopedics, Rigshospitalet. The minimum length of follow-up with respect to survival was 5-7 years. Immunohistochemical analysis with anti-YKL-40 antibody using tissue microarray was performed on resected tumors, and a semiquantitative measure of the intensity of YKL-40 staining was performed. RESULTS: 41 of the 49 tumors were positive for YKL-40, and of these, 36 had moderate to intense staining. 24 of the patients died within the follow-up period, and the intensity of YKL-40 staining was significantly higher in tumors from patients who had died in the follow-up period than in tumors from those who survived (p = 0.01). The staining intensity was different for the 3 grades of malignancy (p = 0.004): it was higher in highly malignant tumors (FNCLCC grade 2 and grade 3) than in low-malignancy tumors (grade 1). INTERPRETATION: YKL-40 is expressed in soft-tissue sarcomas. There is a correlation between expression of YKL-40 in STS and both histological grade of the malignancy and survival. Whether or not YKL-40 expression is an independent prognostic variable could not be determined in the present study.
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Adipoquinas/metabolismo , Biomarcadores de Tumor/metabolismo , Lectinas/metabolismo , Lipoma/metabolismo , Sarcoma/metabolismo , Neoplasias de los Tejidos Blandos/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Proteína 1 Similar a Quitinasa-3 , Estudios de Cohortes , Femenino , Humanos , Inmunohistoquímica , Lipoma/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Sarcoma/mortalidad , Neoplasias de los Tejidos Blandos/mortalidad , Adulto JovenRESUMEN
Lactic acid bacteria (LAB) have evolved into fastidious microorganisms that require amino acids from environmental sources. Some LAB have cell envelope proteases (CEPs) that drive the proteolysis of high molecular weight proteins like casein in milk. CEP activity is typically studied using casein as the predominant substrate, even though CEPs can hydrolyze other protein sources. Plant protein hydrolysis by LAB has rarely been connected to the activity of specific CEPs. This study aims to show the activity of individual CEPs using LAB growth in a minimal growth medium supplemented with high molecular weight casein or potato proteins. Using Lactococcus cremoris MG1363 as isogenic background to express CEPs, we demonstrate that CEP activity is directly related to growth in the protein-supplemented minimal growth media. Proteolysis is analyzed based on the amino acid release, allowing a comparison of CEP activities and analysis of amino acid utilization by L. cremoris MG1363. This approach provides a basis to analyze CEP activity on plant-based protein substrates as casein alternatives and to compare activity of CEP homologs.
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Lactococcus lactis , Péptido Hidrolasas , Animales , Péptido Hidrolasas/metabolismo , Caseínas/metabolismo , Peso Molecular , Endopeptidasas/química , Lactococcus lactis/metabolismo , Aminoácidos/metabolismoRESUMEN
BACKGROUND: The etiology of long-lasting adverse reactions to gel fillers used in cosmetic surgery is not known. Bacterial infection and immunological reaction to the product have been suggested. METHODS: We performed a case-control study, with 77 biopsies and 30 cytology specimens originating from 59 patients with adverse reactions to polyacrylamide gel, and 54 biopsies and 2 cytology specimens from 28 control subjects with no adverse reactions. Samples from 5 patients and 4 controls could not be investigated for presence of bacteria owing to limited material. Samples from the remaining 54 patients and 24 controls were systematically examined for the presence of bacteria by culture, 16S rRNA gene sequencing, Gram stain, and fluorescence in situ hybridization. RESULTS: Bacteria, mostly normal skin bacteria such as Staphylococcus epidermidis and Propionibacterium acnes, were identified in bacteriologically investigated samples from 53 of 54 patients (98%), and in none of the 24 controls (0%). The bacteria were lying in small clusters, which in symptomatic lesions were detected up to 5 years postinjection. CONCLUSIONS: Commensal bacteria of low virulence are capable of producing long-term infection in the presence of polyacrylamide filler in cosmetic surgery, possibly due to a biofilm mode of growth. Adequate skin preparation and use of sterile technique in these procedures are mandatory, but antibiotic prophylaxis prior to injection of nondegradable gels like polyacrylamide should be explored as well.
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Resinas Acrílicas/efectos adversos , Infecciones Bacterianas/etiología , Infecciones Bacterianas/microbiología , Técnicas Cosméticas/efectos adversos , Hidrogeles/efectos adversos , Prótesis e Implantes/microbiología , Cirugía Plástica/efectos adversos , Adulto , Anciano , Bacterias/clasificación , Bacterias/aislamiento & purificación , Biopelículas , Biopsia , Estudios de Casos y Controles , Femenino , Mano/microbiología , Histocitoquímica , Humanos , Labio/química , Labio/microbiología , Masculino , Persona de Mediana Edad , Prótesis e Implantes/efectos adversosRESUMEN
Gene silencing by DNA hypermethylation of CpG islands is a well-characterized phenomenon in cancer. The effect of hypomethylation in particular of non-CpG island genes is much less well described. By genome-wide screening, we identified 105 genes in microsatellite stable (MSS) colorectal adenocarcinomas with an inverse correlation (Spearman's ρ ≤ -0.40) between methylation and expression. Of these, 35 (33%) were hypomethylated non-CpG island genes and two of them, APOLD1 (Spearman's ρ = -0.82) and SRPX2 (Spearman's ρ = -0.80) were selected for further analyses. Hypomethylation of both genes were localized events not shared by adjacent genes. A set of 662 FFPE DNA samples not only confirmed that APOLD1 and SRPX2 are hypomethylated in CRC but also revealed hypomethylation to be significantly (p < 0.01) associated with tumors being localized in the left side, CpG island methylator phenotype negative, MSS, BRAF wt, undifferentiated and of adenocarcinoma histosubtype. Demethylation experiments supported SRPX2 being epigenetically regulated via DNA methylation, whereas other mechanisms in addition to DNA methylation seem to be involved in the regulation of APOLD1. We further identified miR-149 as a potential novel post-transcriptional regulator of SRPX2. In carcinoma tissue, miR-149 was downregulated and inversely correlated to SRPX2 (ρ = -0.77). Furthermore, ectopic expression of miR-149 significantly reduced SRPX2 transcript levels. Our study highlights that in colorectal tumors, hypomethylation of non-CpG island-associated promoters deregulate gene expression nearly as frequent as do CpG-island hypermethylation. The hypomethylation of SRPX2 is focal and not part of a large block. Furthermore, it often translates to an increased expression level, which may be modulated by miR-149.
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Adenocarcinoma/genética , Neoplasias Colorrectales/genética , Metilación de ADN , MicroARNs/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Regiones Promotoras Genéticas , Adenoma/genética , Apolipoproteínas/metabolismo , Islas de CpG , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas de la Membrana , Inestabilidad de Microsatélites , Proteínas de Neoplasias , Regiones Promotoras Genéticas/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Transcripción Genética , TranscriptomaRESUMEN
Colorectal cancer (CRC) is one of the leading causes of cancer deaths in Western countries. A significant number of CRC patients undergoing curatively intended surgery subsequently develop recurrence and die from the disease. MicroRNAs (miRNAs) are aberrantly expressed in cancers and appear to have both diagnostic and prognostic significance. In this study, we identified novel miRNAs associated with recurrence of CRC, and their possible mechanism of action. TaqMan(®) Human MicroRNA Array Set v2.0 was used to profile the expression of 667 miRNAs in 14 normal colon mucosas and 46 microsatellite stable CRC tumors. Four miRNAs (miR-362-3p, miR-570, miR-148 a* and miR-944) were expressed at a higher level in tumors from patients with no recurrence (p<0.015), compared with tumors from patients with recurrence. A significant association with increased disease free survival was confirmed for miR-362-3p in a second independent cohort of 43 CRC patients, using single TaqMan(®) microRNA assays. In vitro functional analysis showed that over-expression of miR-362-3p in colon cancer cell lines reduced cell viability, and proliferation mainly due to cell cycle arrest. E2F1, USF2 and PTPN1 were identified as potential miR-362-3p targets by mRNA profiling of HCT116 cells over-expressing miR-362-3p. Subsequently, these genes were confirmed as direct targets by Luciferase reporter assays and their knockdown in vitro phenocopied the effects of miR-362-3p over-expression. We conclude that miR-362-3p may be a novel prognostic marker in CRC, and hypothesize that the positive effects of augmented miR-362-3p expression may in part be mediated through the targets E2F1, USF2 and PTPN1.
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Biomarcadores de Tumor/metabolismo , Puntos de Control del Ciclo Celular , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Factor de Transcripción E2F1/metabolismo , MicroARNs/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Factores Estimuladores hacia 5'/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Proliferación Celular , Supervivencia Celular , Colon/metabolismo , Colon/patología , Neoplasias Colorrectales/genética , Factor de Transcripción E2F1/genética , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Mucosa Intestinal/metabolismo , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Pronóstico , Modelos de Riesgos Proporcionales , Proteína Tirosina Fosfatasa no Receptora Tipo 1/genética , Recurrencia , Regulación hacia Arriba , Factores Estimuladores hacia 5'/genéticaRESUMEN
This state-of-the-art review evaluates whether contraceptive apps could improve knowledge resulting in greater interest and use of long-acting contraception, what type of information an app should contain, and who may benefit most from apps. The studies found a high interest in easy accessibility and respect for privacy. Science-based information and facilitation of knowledge about all contraceptives were desired. Contraceptive apps were useful in presenting women with validated information and complement professional advice.
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Anticoncepción , Anticonceptivos , Femenino , Humanos , Anticoncepción/métodosRESUMEN
Lactic acid bacteria (LAB) have an extracellular proteolytic system that includes a multi-domain, cell envelope protease (CEP) with a subtilisin homologous protease domain. These CEPs have different proteolytic activities despite having similar protein sequences. Structural characterization has previously been limited to CEP homologs of dairy- and human-derived LAB strains, excluding CEPs of plant-derived LAB strains. CEP structures are a challenge to determine experimentally due to their large size and attachment to the cell envelope. This study aims to clarify the prevalence and structural diversity of CEPs by using the structure prediction software AlphaFold 2. Domain boundaries are clarified based on a comparative analysis of 21 three-dimensional structures, revealing novel domain architectures of CEP homologs that are not necessarily restricted to specific LAB species or ecological niches. The C-terminal flanking region of the protease domain is divided into fibronectin type-III-like domains with various structural traits. The analysis also emphasizes the existence of two distinct domains for cell envelope attachment that are preceded by an intrinsically disordered cell wall spanning domain. The domain variants and their combinations provide CEPs with different stability, proteolytic activity, and potentially adhesive properties, making CEPs targets for steering proteolytic activity with relevance for both food development and human health.