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Current knowledge on the capacity of plastics as vectors of microorganisms and their ability to transfer microorganisms between different habitats (i.e. air, soil and river) is limited. The objective of this study was to characterise the evolution of the bacterial community adhered to environmental plastics [low-density polyethylene (LDPE)] across different environments from their point of use to their receiving environment destination in the sea. The study took place in a typical Mediterranean intermittent river basin in Larnaka, Cyprus, characterised by a large greenhouse area whose plastic debris may end up in the sea due to mismanagement. Five locations were selected to represent the environmental fate of greenhouse plastics from their use, through their abandonment in soil and subsequent transport to the river and the sea, taking samples of plastics and the surrounding environments (soil and water). The bacterial community associated with each sample was studied by 16S rRNA metabarcoding; also, the main physicochemical parameters in each environmental compartment were analysed to understand these changes. The identification and chemical changes in greenhouse plastics were tracked using Attenuated Total Reflection Fourier Transform Infra-red spectroscopy (ATR-FTIR). Scanning Electron Microscope (SEM) analysis demonstrated an evolution of the biofilm at each sampling location. ß-diversity studies showed that the bacterial community adhered to plastics was significantly different from that of the surrounding environment only in samples taken from aqueous environments (freshwater and sea) (p-value p-value > 0.05). The environmental parameters (pH, salinity, total nitrogen and total phosphorus) explained the differences observed at each location to a limited extent. Furthermore, bacterial community differences among samples were lower in plastics collected from the soil than in plastics taken from rivers and seawater. Six genera (Flavobacterium, Altererythrobacter, Acinetobacter, Pleurocapsa, Georgfuchsia and Rhodococcus) were detected in the plastic, irrespective of the sampling location, confirming that greenhouse plastics can act as possible vectors of microorganisms between different environments: from their point of use, through a river system to the final coastal receiving environment. In conclusion, this study confirms the ability of greenhouse plastics to transport bacteria, including pathogens, between different environments. Future studies should evaluate these risks by performing complete sequencing metagenomics to decipher the functions of the plastisphere.
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Plásticos , Água do Mar , Bactérias/genética , RNA Ribossômico 16S/genética , Rios , Água do Mar/microbiologiaRESUMO
BACKGROUND: The onset of puberty is influenced by the interplay of stimulating and restraining factors, many of which have a genetic origin. Premature activation of the GnRH secretion in central precocious puberty (CPP) may arise either from gain-of-function mutations of the KISS1 and KISS1R genes or from loss-of-function manner mutations of the MKRN3 gene leading to MKRN3 deficiency. OBJECTIVE: To explore the genetic causes responsible for CPP and the potential role of the RING finger protein 3 (MKRN3) gene. DESIGN AND PATIENTS: We investigated potential sequence variations in the intronless MKRN3 gene by Sanger sequencing of the entire 507 amino acid coding region of exon 1 in a family with two affected girls presented with CPP at the age of 6 and 5·7 years, respectively. RESULTS: A novel heterozygous g.Gly312Asp missense mutation in the MKRN3 gene was identified in these siblings. The imprinted MKRN3 missense mutation was also identified as expected in the unaffected father and followed as expected an imprinted mode of inheritance. In silico analysis of the altered missense variant using the computational algorithms Polyphen2, SIFT and Mutation Taster predicted a damage and pathogenic alteration causing CPP. The pathogenicity of the alteration at the protein level via an in silico structural model is also explored. CONCLUSION: A novel mutation in the MKRN3 gene in two sisters with CPP was identified, supporting the fundamental role of this gene in the suppression of the hypothalamic GnRH neurons.
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Simulação por Computador , Predisposição Genética para Doença/genética , Mutação de Sentido Incorreto , Puberdade Precoce/genética , Ribonucleoproteínas/genética , Sequência de Aminoácidos , Criança , Pré-Escolar , Análise Mutacional de DNA , Saúde da Família , Feminino , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Conformação Proteica , Ribonucleoproteínas/química , Irmãos , Ubiquitina-Proteína LigasesRESUMO
Steinfeld syndrome (MIM #184705) was first reported in 1982. It is characterised by holoprosencephaly and limb defects, however other anomalies may also be present. Following the initial description, three further cases have been reported in the literature. We report on a 23-year-old girl, with features of microform holoprosencephaly and bilateral congenital elbow dislocation in association with hypoplastic radial heads. She was identified to have a variant in the CDON gene inherited from her father who had ocular hypotelorism, but no other clinical features. We discuss the clinical features of Steinfeld syndrome, and broaden the phenotypic spectrum of this condition. Structural analysis suggests that this variant could lead to destabilisation of binding of CDON with hedgehog proteins. Further work needs to be done to confirm whether mutations in the CDON gene are the cause of Steinfeld syndrome.
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Cardiopatias Congênitas/diagnóstico , Holoprosencefalia/diagnóstico , Deformidades Congênitas dos Membros/diagnóstico , Fenótipo , Sequência de Aminoácidos , Encéfalo/patologia , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/genética , Hibridização Genômica Comparativa , Fácies , Feminino , Cardiopatias Congênitas/genética , Heterozigoto , Holoprosencefalia/genética , Humanos , Deformidades Congênitas dos Membros/genética , Imageamento por Ressonância Magnética , Modelos Moleculares , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Conformação Proteica , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética , Adulto JovemRESUMO
Familial Mediterranean fever (FMF) is caused by mutations in the MEFV gene and the spectrum of mutations among Greek-Cypriots with FMF-related symptoms was examined. Sequence analysis for exons 2, 3, 5, and 10 of the MEFV gene was performed in a cohort of 593 patients. A total of 70 patients carried mutations in the homozygote or compound heterozygote state, 128 were identified with one MEFV mutation and 395 had no mutations. Of the 268 identified alleles, p.Val726Ala (27.61%) was the most frequent followed by p.Met694Val (19.40%). The missense mutations p.Arg761His (3.73%) and p.Ala744Ser (2.24%) were identified as the rarest. An interesting finding is the high frequency (18.28%) of the complex p.Phe479Leu-p.Glu167Asp that was identified in 49 of the mutated alleles. The MEFV genotypes did not follow a binomial distribution and proved not to satisfy the HWE (P < 0.001). The high percentage (66.61%) of patients with unidentified mutations could be due to mutations in the rest of the coding or noncoding MEFV gene or due to mutations in other genes that are also causing Hereditary Recurrent Fevers. Results from this work indicate the high incidence of FMF in Cyprus and describe the spectrum of the mutations which occur in the country.
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Proteínas do Citoesqueleto/genética , Febre Familiar do Mediterrâneo/genética , Adulto , Alelos , Estudos de Coortes , Chipre , Análise Mutacional de DNA , Éxons , Feminino , Frequência do Gene , Genótipo , Heterozigoto , Homozigoto , Humanos , Masculino , Mutação de Sentido Incorreto , PirinaRESUMO
The highly conserved 29-mer RNA motif corresponding to the peptidyl transferase central circle region of the domain V of Halobacterium halobium 23S rRNA has been characterised by multidimensional NMR spectroscopy. The NMR structure has a good all atom average RMSD of 1.28 Å and a stable A-form helical conformation. The NMR structure differs from the X-ray crystal structure of an analogous motif, contained within the Escherichia coli ribosome, as none of the bases are flipped out and a number of non-canonical base pairs are formed in the solution structure. Thus in the observed NMR structure, the predicted A7 to U30 base pair is not seen and a non-canonical U6 to U30 base pair was formed in its place. Similarly the predicted A9 to U26 base pair was also not observed and another non-canonical A9 to A27 base pair was formed. It was also seen from the conformational analysis that the steps near the bulges had the greatest deviation from the canonical Watson-Crick base pair step parameters. Despite these differences, the 29-mer structure provides a working model of the RNA within the ribosome in a more natural solution state than that observed in the intact ribosome crystal structures, particularly around the A27 residue. The NMR structure determination of the 29-mer RNA motif provides a solid foundation for determining the NMR structure of the RNA-amicetin complex in the next step. To extend the above study, a fully (13)C and (15)N isotopically labelled 37-mer RNA version of the Halobacterium halobium RNA sample has been characterised using ultra high field 1 GHz spectroscopy. The results have been used to demonstrate the advantages conferred by the use of a 1 GHz spectrometer frequency over 800 MHz in terms of superior sensitivity and greater spectral dispersion achieved in the spectrum of the RNA.
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Halobacterium/química , RNA Ribossômico 23S/química , Cristalografia por Raios X , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Conformação de Ácido NucleicoRESUMO
Microbiota and the metabolites they produce within the large intestine interact with the host epithelia under the influence of a range of host-derived metabolic, immune, and homeostatic factors. This complex host-microbe interaction affects intestinal tumorigenesis, but established microbial or metabolite profiles predicting colorectal cancer (CRC) risk are missing. Here, we aimed to identify fecal bacteria, volatile organic compounds (VOC), and their associations that distinguish healthy (non-adenoma, NA) from CRC prone (high-risk adenoma, HRA) individuals. Analyzing fecal samples obtained from 117 participants ≥15 days past routine colonoscopy, we highlight the higher abundance of Proteobacteria and Parabacteroides distasonis, and the lower abundance of Lachnospiraceae species, Roseburia faecis, Blautia luti, Fusicatenibacter saccharivorans, Eubacterium rectale, and Phascolarctobacterium faecium in the samples of HRA individuals. Volatolomic analysis of samples from 28 participants revealed a higher concentration of five compounds in the feces of HRA individuals, isobutyric acid, methyl butyrate, methyl propionate, 2-hexanone, and 2-pentanone. We used binomial logistic regression modeling, revealing 68 and 96 fecal bacteria-VOC associations at the family and genus level, respectively, that distinguish NA from HRA endpoints. For example, isobutyric acid associations with Lachnospiraceae incertae sedis and Bacteroides genera exhibit positive and negative regression lines for NA and HRA endpoints, respectively. However, the same chemical associates with Coprococcus and Colinsella genera exhibit the reverse regression line trends. Thus, fecal microbiota and VOC profiles and their associations in NA versus HRA individuals indicate the significance of multiple levels of analysis towards the identification of testable CRC risk biomarkers.
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Commencing in December 2019 with the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), three years of the coronavirus disease 2019 (COVID-19) pandemic have transpired. The virus has consistently demonstrated a tendency for evolutionary adaptation, resulting in mutations that impact both immune evasion and transmissibility. This ongoing process has led to successive waves of infections. This study offers a comprehensive assessment spanning genetic, phylogenetic, phylodynamic, and phylogeographic dimensions, focused on the trajectory of the SARS-CoV-2 epidemic in Cyprus. Based on a dataset comprising 4700 viral genomic sequences obtained from affected individuals between October 2021 and October 2022, our analysis is presented. Over this timeframe, a total of 167 distinct lineages and sublineages emerged, including variants such as Delta and Omicron (1, 2, and 5). Notably, during the fifth wave of infections, Omicron subvariants 1 and 2 gained prominence, followed by the ascendancy of Omicron 5 in the subsequent sixth wave. Additionally, during the fifth wave (December 2021-January 2022), a unique set of Delta sequences with genetic mutations associated with Omicron variant 1, dubbed "Deltacron", was identified. The emergence of this phenomenon initially evoked skepticism, characterized by concerns primarily centered around contamination or coinfection as plausible etiological contributors. These hypotheses were predominantly disseminated through unsubstantiated assertions within the realms of social and mass media, lacking concurrent scientific evidence to validate their claims. Nevertheless, the exhaustive molecular analyses presented in this study have demonstrated that such occurrences would likely lead to a frameshift mutation-a genetic aberration conspicuously absent in our provided sequences. This substantiates the accuracy of our initial assertion while refuting contamination or coinfection as potential etiologies. Comparable observations on a global scale dispelled doubt, eventually leading to the recognition of Delta-Omicron variants by the scientific community and their subsequent monitoring by the World Health Organization (WHO). As our investigation delved deeper into the intricate dynamics of the SARS-CoV-2 epidemic in Cyprus, a discernible pattern emerged, highlighting the major role of international connections in shaping the virus's local trajectory. Notably, the United States and the United Kingdom were the central conduits governing the entry and exit of the virus to and from Cyprus. Moreover, notable migratory routes included nations such as Greece, South Korea, France, Germany, Brazil, Spain, Australia, Denmark, Sweden, and Italy. These empirical findings underscore that the spread of SARS-CoV-2 within Cyprus was markedly influenced by the influx of new, highly transmissible variants, triggering successive waves of infection. This investigation elucidates the emergence of new waves of infection subsequent to the advent of highly contagious and transmissible viral variants, notably characterized by an abundance of mutations localized within the spike protein. Notably, this discovery decisively contradicts the hitherto hypothesis of seasonal fluctuations in the virus's epidemiological dynamics. This study emphasizes the importance of meticulously examining molecular genetics alongside virus migration patterns within a specific region. Past experiences also emphasize the substantial evolutionary potential of viruses such as SARS-CoV-2, underscoring the need for sustained vigilance. However, as the pandemic's dynamics continue to evolve, a balanced approach between caution and resilience becomes paramount. This ethos encourages an approach founded on informed prudence and self-preservation, guided by public health authorities, rather than enduring apprehension. Such an approach empowers societies to adapt and progress, fostering a poised confidence rooted in well-founded adaptation.
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COVID-19 , Coinfecção , Humanos , SARS-CoV-2/genética , Chipre/epidemiologia , Filogenia , COVID-19/epidemiologia , Genômica , PandemiasRESUMO
Polycystic ovary syndrome (PCOS) is a very common endocrine condition in women in India. Gut microbiome alterations were shown to be involved in PCOS, yet it is remarkably understudied in Indian women who have a higher incidence of PCOS as compared to other ethnic populations. During the regional PCOS screening program among young women, we recruited 19 drug naive women with PCOS and 20 control women at the Sher-i-Kashmir Institute of Medical Sciences, Kashmir, North India. We profiled the gut microbiome in faecal samples by 16S rRNA sequencing and included 40/58 operational taxonomic units (OTUs) detected in at least 1/3 of the subjects with relative abundance (RA) ≥ 0.1%. We compared the RAs at a family/genus level in PCOS/non-PCOS groups and their correlation with 33 metabolic and hormonal factors, and corrected for multiple testing, while taking the variation in day of menstrual cycle at sample collection, age and BMI into account. Five genera were significantly enriched in PCOS cases: Sarcina, Megasphaera, and previously reported for PCOS Bifidobacterium, Collinsella and Paraprevotella confirmed by different statistical models. At the family level, the relative abundance of Bifidobacteriaceae was enriched, whereas Peptococcaceae was decreased among cases. We observed increased relative abundance of Collinsella and Paraprevotella with higher fasting blood glucose levels, and Paraprevotella and Alkalibacterium with larger hip, waist circumference, weight, and Peptococcaceae with lower prolactin levels. We also detected a novel association between Eubacterium and follicle-stimulating hormone levels and between Bifidobacterium and alkaline phosphatase, independently of the BMI of the participants. Our report supports that there is a relationship between gut microbiome composition and PCOS with links to specific reproductive health metabolic and hormonal predictors in Indian women.
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Microbioma Gastrointestinal , Síndrome do Ovário Policístico , Bacteroidetes/genética , Bifidobacterium/genética , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Humanos , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo , RNA Ribossômico 16S/genéticaRESUMO
Breast cancer patients are at a particularly high risk of cardiotoxicity from chemotherapy having a detrimental effect on quality-of-life parameters and increasing the risk of mortality. Prognostic biomarkers would allow the management of therapies to mitigate the risks of cardiotoxicity in vulnerable patients and a key potential candidate for such biomarkers are microRNAs (miRNA). miRNAs are post-transcriptional regulators of gene expression which can also be released into the circulatory system and have been associated with the progression of many chronic diseases including many types of cancer. In this review, the evidence for the potential application of miRNAs as biomarkers for chemotherapy-induced cardiotoxicity (CIC) in breast cancer patientsis evaluated and a simple meta-analysis is performed to confirm the replication status of each reported miRNA. Further selection of miRNAs is performed by reviewing the reported associations of each miRNA with other cardiovascular conditions. Based on this research, the most representative panels targeting specific chemotherapy agents and treatment regimens are suggested, that contain several informative miRNAs, including both general markers of cardiac damage as well as those for the specific cancer treatments.
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The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in December 2019 resulted in the coronavirus disease 2019 (COVID-19) pandemic, which has had devastating repercussions for public health. Over the course of this pandemic, the virus has continuously been evolving, resulting in new, more infectious variants that have frequently led to surges of new SARS-CoV-2 infections. In the present study, we performed detailed genetic, phylogenetic, phylodynamic and phylogeographic analyses to examine the SARS-CoV-2 epidemic in Cyprus using 2352 SARS-CoV-2 sequences from infected individuals in Cyprus during November 2020 to October 2021. During this period, a total of 61 different lineages and sublineages were identified, with most falling into three groups: B.1.258 & sublineages, Alpha (B.1.1.7 & Q. sublineages), and Delta (B.1.617.2 & AY. sublineages), each encompassing a set of S gene mutations that primarily confer increased transmissibility as well as immune evasion. Specifically, these lineages were coupled with surges of new infections in Cyprus, resulting in the following: the second wave of SARS-CoV-2 infections in Cyprus, comprising B.1.258 & sublineages, during late autumn 2020/beginning of winter 2021; the third wave, comprising Alpha (B.1.1.7 & Q. sublineages), during spring 2021; and the fourth wave, comprising Delta (B.1.617.2 & AY. sublineages) during summer 2021. Additionally, it was identified that these lineages were primarily imported from and exported to the UK, Greece, and Sweden; many other migration links were also identified, including Switzerland, Denmark, Russia, and Germany. Taken together, the results of this study indicate that the SARS-CoV-2 epidemic in Cyprus was characterized by successive introduction of new lineages from a plethora of countries, resulting in the generation of waves of infection. Overall, this study highlights the importance of investigating the spatiotemporal evolution of the SARS-CoV-2 epidemic in the context of Cyprus, as well as the impact of protective measures placed to mitigate transmission of the virus, providing necessary information to safeguard public health.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Chipre/epidemiologia , Filogenia , COVID-19/epidemiologia , Genômica , PandemiasRESUMO
DM1 (myotonic dystrophy type I) is a common form of muscular dystrophy that affects mainly adults. It is a disease that belongs to the group of defective RNA export diseases, since a major part of the pathogenic mechanism of the disease is the retention of the mutant transcripts in the cell nucleus. The presence of an expanded CUG trinucleotide repeat in the 3'-UTR (3'-untranslated region) of the DMPK (myotonic dystrophy protein kinase) gene causes the attraction of RNA-binding proteins by the nuclear-located mutant transcripts. As a result of the occupation of the RNA-binding proteins, there is defective mis-splicing of several cellular transcripts. This is believed to be a major pathogenic mechanism of the disease and any attempt to repair the activities of the RNA-binding proteins or target the mutant transcripts should be beneficial for the patients. Certain approaches have been described in the literature and they demonstrate progress in various directions. The purpose of the present review is to summarize the successful attempts to tackle the pathogenesis caused by nuclear retention of mutant transcripts in myotonic dystrophy and to discuss the possible gains from such approaches.
Assuntos
Núcleo Celular/metabolismo , Distrofia Miotônica/etiologia , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro Estocado/genética , RNA Mensageiro/metabolismo , Expansão das Repetições de Trinucleotídeos , Regiões 3' não Traduzidas , Adulto , Núcleo Celular/genética , Humanos , Mutação , Distrofia Miotônica/genética , Distrofia Miotônica/terapia , Miotonina Proteína Quinase , RNA Mensageiro Estocado/metabolismo , RNA Nuclear/genética , RNA Nuclear/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismoRESUMO
BACKGROUND: The detection and diagnosis of ß-thalassaemia for populations with molecular heterogeneity, or diverse ethnic groups, has increased the need for the development of an array high-throughput diagnostic tool that can deliver large scale genetic detection. We report on the update and validation of the ThalassoChip, a ß-thalassaemia genetic diagnostic tool which is based on arrayed primer extension (APEX) technology. METHODS: ThalassoChip slides with new and redesigned probes were prepared for testing the microarray. Six hundred and sixty DNA samples collected from eight Mediterranean countries were used for standardisation, optimisation and validation of the ThalassoChip. The ß-globin gene region was amplified by PCR, the products were hybridised to the probes after fragmentation and the APEX reaction followed. RESULTS: The ThalassoChip was updated with new probes and now has the ability to detect 57 ß-globin gene mutations and three single nucleotide polymorphisms (SNPs) in a single test. The ThalassoChip as well as the PCR and APEX reactions were standardised and optimised using 500 DNA samples that were previously genotyped using conventional diagnostic techniques. Some probes were redesigned in order to improve the specificity and sensitivity of the test. Validation of the ThalassoChip performed using 160 samples analysed in blinded fashion showed no error. CONCLUSIONS: The updated version of the ThalassoChip is versatile, robust, cost-effective and easily adaptable, but most notably can provide comprehensive genetic diagnosis for ß-thalassaemia and other haemoglobinopathies.
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Ensaios de Triagem em Larga Escala/métodos , Mutação , Polimorfismo de Nucleotídeo Único , Talassemia beta/diagnóstico , Sondas de DNA/normas , Hemoglobinopatias/diagnóstico , Hemoglobinopatias/genética , Humanos , Sensibilidade e Especificidade , Globinas beta/genética , Talassemia beta/genéticaRESUMO
BACKGROUND: Next-generation sequencing has revolutionized our perspective on the gut microbiome composition, revealing the true extent of the adverse effects of antibiotics. The impact of antibiotic treatment on gut microbiota must be considered and researched to provide grounds for establishing new treatment strategies that are less devastating on commensal bacteria. This study investigates the impact on gut microbiome when a commonly used antibiotic, azithromycin is administered, as well as uncovers the benefits induced when it is used in combination with lactulose, a prebiotic known to enhance the proliferation of commensal microbes. METHODS: 16S rRNA gene sequencing analysis of stool samples obtained from 87 children treated with azithromycin in combination with or without lactulose have been determined. Children's gut microbial profile was established at the pre- and post-treatment stage. RESULTS: Azithromycin caused an increase in the relative abundance of opportunistic pathogens such as Streptococcus that was evident 60 days after treatment. While few days after treatment, children who also received lactulose started to show a higher relative abundance of saccharolytic bacteria such as Lactobacillus, Enterococcus, Anaerostipes, Blautia and Roseburia, providing a protective role against opportunistic pathogens. In addition, azithromycin-prebiotic combination was able to provide a phylogenetic profile more similar to the pre-treatment stage. CONCLUSION: It is suggested that during azithromycin treatment, lactulose is able to reinstate the microbiome equilibrium much faster as it promotes saccharolytic microbes and provides a homeostatic effect that minimizes the opportunistic pathogen colonization.
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Antibacterianos/farmacologia , Azitromicina/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Lactulose/farmacologia , Prebióticos , Adolescente , Antibacterianos/administração & dosagem , Azitromicina/administração & dosagem , Criança , Pré-Escolar , Método Duplo-Cego , Combinação de Medicamentos , Humanos , Lactulose/administração & dosagemRESUMO
The prevalence of genetic variants associated to cutaneous melanoma (CM) has never been determined within Cypriot melanomas. This study evaluates the frequency of variants in cyclin-dependent kinase inhibitor 2A (CDKN2A) and melanocortin-1 receptor (MC1R) in 32 patients diagnosed with CM. Other characteristics and risk factors were also assessed. CDKN2A p.Ala148Thr was detected in three of 32 patients, while the control group revealed no variations within CDKN2A. MC1R screening in 32 patients revealed the following variations: p.Val60Leu in 11 patients, p.Arg142His in four patients, p.Thr314Thr in one patient, p.Arg160Trp in one patient, p.Val92Met/p.Thr314Thr in one patient and p.Val92Met/p.Arg142His/p.Thr314Thr in one patient. The control group revealed only p.Val60Leu (in 10 of 45 individuals), which is frequently found in general populations. Two unrelated patients carried CDKN2A p.Ala148Thr in combination with MC1R p.Arg142His, suggesting digenic inheritance that may provide evidence of different gene variants acting synergistically to contribute for CM development. This study confirms the presence of CDKN2A and MC1R variants among Cypriot melanomas and supports existing evidence of a role for these variants in susceptibility to melanoma.
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Inibidor p16 de Quinase Dependente de Ciclina/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Melanoma/diagnóstico , Melanoma/genética , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/genética , Adulto , Idoso , Alelos , Substituição de Aminoácidos , Feminino , Genótipo , Grécia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Melanoma Maligno CutâneoRESUMO
Heterozygosity for CYP21A2 mutations in females is possibly related to increased risk of developing clinical hyperandrogenism. The present study was designed to seek evidence on the phenotype-genotype correlation in female children, adolescents, and women with CYP21A2 mutations and variants in the 3'UTR region of the gene. Sixty-six patients out of the 169 were identified as carriers of CYP21A2 mutations. Higher values of stimulated 17 hydroxyprogesterone (17-OHP) levels were found in the carriers of the p.Val281Leu mutation compared to the carriers of other mutations (mean: 24.7 nmol/l versus 15.6 nmol/l). The haplotype of the ∗52C>T, ∗440C>T, and ∗443T>C in the 3'UTR was identical in all heterozygous patients with p.Val281Leu and the haplotype of the ∗12C>T and ∗52C>T was identical in all heterozygous patients with the p.Gln318∗. In conclusion, hyperandrogenaemic females are likely to bear heterozygous CYP21A2 mutations. Carriers of the mild p.Val281Leu mutation are at higher risk of developing hyperandrogenism than the carriers of more severe mutations. The identification of variants in the 3'UTR of CYP21A2 in combination with the heterozygous mutation may be associated with the mild form of nonclassic congenital adrenal hyperplasia and reveal the importance of analyzing the CYP21A2 untranslated regions for the appropriate management of this category of patients.
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The interaction of a highly conserved secondary structural RNA motif of Halobacterium halobium and Escherichia coli 23S ribosomal RNAs with the peptidyl transferase inhibitor antibiotic amicetin has been investigated by proton NMR spectroscopy and molecular modelling. The NMR spectra of the synthetic 35mer RNA motifs revealed spectral features characteristic of a stable, well folded A-RNA type tertiary conformation, including resolved resonances assigned to unpaired bases located in the middle of the motif strongly implicated in amicetin binding. Addition of amicetin to the 35mer RNA samples was accompanied by significant and discrete changes to the spectra which can be qualitatively interpreted to the changes induced to the local conformation of the RNA motifs arising from the formation of a specific complex with amicetin. These results are also supported by the unconstrained molecular model of RNA-amicetin complex which highlights potential interactions between the two molecular components.
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Antibacterianos/metabolismo , RNA Ribossômico 23S/química , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Nucleosídeos de Pirimidina/química , Nucleosídeos de Pirimidina/metabolismo , RNA Ribossômico 23S/metabolismoRESUMO
OBJECTIVE: Congenital adrenal hyperplasia (CAH) is an endocrine autosomal recessive disorder with various symptoms of diverse severity. Mild hyperandrogenemia is the most commonclinical feature in non-classic CAH patients and 95% of the cases are identified by mutations in the CYP21A2 gene. In the present study, the second most common cause for non-classic CAH (NC-CAH), 11ß-hydroxylase deficiency due to mutations in the CYP11B1 gene, is investigated. DESIGN: Screening of the CYP21A2 and CYP11B1 genes by direct sequencing was carried out for the detection of possible genetic defects in patients with suspected CAH. RES ULTS: It wasobserved that CYP11B1 variants co-exist only in rare cases along with mutations in CYP21A2 in patients clinically diagnosed with CAH. A total of 23 NC-CAH female patients out of 75 were identified with only one mutation in the CYP21A2 gene. The novel CYP11B1 gene mutation, p.Val484Asp, was identified in a patient with CAH in the heterozygous state. The structural characterization of the novel p.Val484Asp was found to likely cause distortion of the surrounding beta sheet and indirect destabilization of the cavity that occurs on the opposite face of the structural elements, leading to partial impairment of the enzymatic activity. CONCLUSIONS: CYP21A2 gene mutations are the most frequent genetic defects in cases of NC-CAH even when these patients are in the heterozygous state. These mutations have a diverse phenotype giving rise to a variable extent of cortisol synthesis impairment; it is also clear that CYP11B1 mutants are a rare type of defects causing CAH.
Assuntos
Hiperplasia Suprarrenal Congênita/genética , Análise Mutacional de DNA , Testes Genéticos/métodos , Hiperandrogenismo/genética , Mutação , Esteroide 11-beta-Hidroxilase/genética , Adolescente , Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/enzimologia , Criança , Pré-Escolar , Simulação por Computador , Estabilidade Enzimática , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Hiperandrogenismo/diagnóstico , Hiperandrogenismo/enzimologia , Modelos Moleculares , Fenótipo , Valor Preditivo dos Testes , Conformação Proteica em Folha beta , Esteroide 11-beta-Hidroxilase/química , Esteroide 11-beta-Hidroxilase/metabolismo , Esteroide 21-Hidroxilase/genética , Relação Estrutura-AtividadeRESUMO
Familial Mediterranean fever (FMF) has traditionally been considered as a monogenic autosomal recessive disorder caused by mutations in the MEFV gene with highest incidence among Mediterranean populations. In a considerable number of patients with typical FMF, only one MEFV mutation was identified and the possibility that more than one autoinflammatory gene may be responsible for their disease was investigated. In the present study, an extensive search for possible mutations in three hereditary recurrent fever (HRF) genes was performed in 128 MEFV heterozygous Greek-Cypriots clinically diagnosed based on their phenotype with FMF-like disease from a previous study. Sequence analysis was performed for MVK, TNFRSF1A and NLRP3 genes which is also known to cause HRFs. In total, three patients were identified with heterozygous mutations and a second mutation in an autoinflammatory gene. Two patients carried a MEFV mutation and a NLRP3 mutation, and an additional third carried a MEFV mutation and a TNFRSF1A mutation. Patient 1 carried MEFV p.[Val726Ala] (NM_000243.2:c.2177T>C) and NLRP3 p.[Val198Met] (NM_001243133.1:c.592G>A) variants and patient 2 carried MEFV p.[Glu148Gln] (NM_000243.2:c.442G>C) variant which is of uncertain significance and NLRP3 p.[Arg176Trp] (NM_001243133.1:c.526C>T). Lastly, patient 3 was identified to carry MEFV p.[Met694Val] (NM_000243.2:c.2080A>G) and TNFRSF1A p.[Arg121Gln] (NM_001065.3:c.362G>A) variants. The results from this study indicate that screening of genes known to cause HRFs in patients already identified with a single MEFV mutation, can reveal quite rare but potentially causative mutational combinations at different loci. Such interaction provide further evidence for possible locus-locus interactions and phenotypes resulting from digenic inheritance.
Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Inflamação/genética , Padrões de Herança , Adolescente , Adulto , Febre Familiar do Mediterrâneo/diagnóstico , Febre Familiar do Mediterrâneo/tratamento farmacológico , Febre Familiar do Mediterrâneo/genética , Feminino , Humanos , Inflamação/diagnóstico , Inflamação/tratamento farmacológico , Masculino , Mutação , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Linhagem , Fenótipo , Pirina/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Adulto JovemRESUMO
OBJECTIVE: Heterozygous mutations on the melanocortin-4-receptor gene (MC4R) are the most frequent cause of monogenic obesity. We describe a novel MC4R deletion in a girl with severe early onset obesity, tall stature, pale skin and red hair. CASE REPORT: Clinical and hormonal parameters were evaluated in a girl born full-term by non-consanguineous parents. Her body mass index (BMI) at presentation (3 years) was 30 kg/m2 (z-score: +4.5SDS). By the age of 5.2 years, she exhibited extreme linear growth acceleration and developed hyperinsulinemia. METHODS: Direct sequencing of the MC4R, MC1Rand for the knownFTOsingle nucleotide polymorphism (SNP) rs9939609was performed for the patient and her family. RESULTS: A novel heterozygous MC4R p.Met215del (c.643_645delATG) deletion was identified in the patient, her father and her brother, both of whom exhibited a milder phenotype. 3D structural dynamic simulation studies investigated the conformational changes induced by the p.Met215del. The patient and her mother were also found to be carriers of the obesity risk associated FTOrs9939609SNP. Finally, the identification of the known p.Arg160Trp MC1Rvariant in the patient accounts for the red hair and pale skin phenotypic features. CONCLUSION: The p.Met215del causes global conformational and functional changes as it is localized at the alpha-helical transmembrane regions and the membrane spanning regions of the beta-barrel. This novel mutation produces a severe overgrowth phenotype that is apparent as from infancy and is progressive in childhood. The additional negative effect of environmental and unhealthy lifestyle habits as well as a possible co-interaction of FTOrs9939609 SNP may worsen the phenotype.
Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Deleção de Genes , Obesidade Infantil/genética , Polimorfismo de Nucleotídeo Único , Receptor Tipo 1 de Melanocortina/genética , Receptor Tipo 4 de Melanocortina/genética , Idade de Início , Índice de Massa Corporal , Criança , Pré-Escolar , Comportamento Alimentar , Feminino , Predisposição Genética para Doença , Cor de Cabelo/genética , Hereditariedade , Heterozigoto , Humanos , Hiperfagia/genética , Hiperfagia/fisiopatologia , Obesidade Infantil/diagnóstico , Obesidade Infantil/fisiopatologia , Linhagem , Fenótipo , Conformação Proteica , Receptor Tipo 4 de Melanocortina/química , Receptor Tipo 4 de Melanocortina/metabolismo , Índice de Gravidade de Doença , Pigmentação da Pele/genética , Relação Estrutura-AtividadeRESUMO
OBJECTIVES: The objective was to seek evidence on the prevalence and consequences of heterozygous CYP21A2 mutations in girls, adolescent, and adult females with clinical manifestation of androgen excess. PATIENTS AND METHODS: The study included 64 girls diagnosed with premature adrenarche (PA) in childhood and 141 females with clinical hyperandrogenemia manifested in adolescence or adulthood. Direct DNA sequencing and multiplex ligation-dependent probe amplification analysis were used to identify mutations in the CYP21A2 gene. RESULTS: (1) Thirty-four patients were diagnosed with nonclassical-congenital adrenal hyperplasia (NC-CAH) based on the 17-hydroxyprogesterone (17-OHP) levels and the presence of two mutations in CYP21A2 and therefore were excluded from the study, 66 were found to be heterozygotes and finally 105 had no identifiable mutations. The most frequent mutations among the carriers were the mild p.Val281 Leu and p.Qln318stop. Higher levels of mean stimulated 17-OHP were found in the carriers of the p.Val281 Leu. (2) A notable increased allelic frequency for the known p.Asn493 Ser polymorphism was observed in the pool of females with hyperandrogenemia in whom no mutation was identified. (3) In girls, who presented early with PA, 26.6% were diagnosed with NC-CAH and carried two mutations, 28.7% were identified as heterozygotes 43.7% had no identifiable genetic defect in the translated region of the CYP21A2 gene. On the contrary, in the group of 141 females with late onset hyperandrogenemia, the presence of 2 mutations was detected in 12%, 1 mutation in 33.4% and no mutation in 54.6%. CONCLUSIONS: The carrier status for 21-OHD, may be an important factor in the variable phenotype of hyperandrogenism and may be a contributing factor for the early manifestation of the disease.