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1.
Nature ; 601(7893): 422-427, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34987224

RESUMO

Maternal morbidity and mortality continue to rise, and pre-eclampsia is a major driver of this burden1. Yet the ability to assess underlying pathophysiology before clinical presentation to enable identification of pregnancies at risk remains elusive. Here we demonstrate the ability of plasma cell-free RNA (cfRNA) to reveal patterns of normal pregnancy progression and determine the risk of developing pre-eclampsia months before clinical presentation. Our results centre on comprehensive transcriptome data from eight independent prospectively collected cohorts comprising 1,840 racially diverse pregnancies and retrospective analysis of 2,539 banked plasma samples. The pre-eclampsia data include 524 samples (72 cases and 452 non-cases) from two diverse independent cohorts collected 14.5 weeks (s.d., 4.5 weeks) before delivery. We show that cfRNA signatures from a single blood draw can track pregnancy progression at the placental, maternal and fetal levels and can robustly predict pre-eclampsia, with a sensitivity of 75% and a positive predictive value of 32.3% (s.d., 3%), which is superior to the state-of-the-art method2. cfRNA signatures of normal pregnancy progression and pre-eclampsia are independent of clinical factors, such as maternal age, body mass index and race, which cumulatively account for less than 1% of model variance. Further, the cfRNA signature for pre-eclampsia contains gene features linked to biological processes implicated in the underlying pathophysiology of pre-eclampsia.


Assuntos
Ácidos Nucleicos Livres , Pré-Eclâmpsia , RNA , Ácidos Nucleicos Livres/sangue , Feminino , Humanos , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/genética , Valor Preditivo dos Testes , Gravidez , RNA/sangue , Estudos Retrospectivos , Sensibilidade e Especificidade
2.
Int J Legal Med ; 138(4): 1685-1700, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38376570

RESUMO

When dealing with badly preserved cadavers or skeletal human remains, the assessment of death circumstances remains challenging. When forensic evidence cannot be taken from the skin and soft tissue, the information may only be deduced from more resistant elements such as bone. Compared to cranial gunshot injuries, reliable data on ballistic long bone trauma remains scarce. This study aims to define ballistic fracture characteristics in human long bones. The shaft of 16 femurs and 13 humeri from body donors was perpendicularly shot with a 9-mm Luger full metal jacket bullet at an impact velocity of 360 m/s from a distance of 2 m. Some bones were embedded in Clear Ballistics Gel®, and some were shot without soft tissue simulant in order to better visualise the fracture propagation on the high-speed camera. The fractures were examined macroscopically and compared between the sample groups. We consistently found comminuted fractures with a stellate pattern. Fracture details were classified into entrance, exit and general characteristics. For some traits, we detected different occurrence values in the group comparison. The results indicate that some of the traits depend on bone properties such as shaft diameter, bone length and cortical thickness. The presence of ballistic gel also influenced some fracture traits, emphasising the relevance of soft tissue simulant in osseous gunshot experiments. This study revealed new insights in the detailed fracture pattern of human long bones. These may serve as guidelines for the identification and reconstruction of gunshot trauma in human long bones.


Assuntos
Balística Forense , Ferimentos por Arma de Fogo , Humanos , Balística Forense/métodos , Ferimentos por Arma de Fogo/patologia , Masculino , Pessoa de Meia-Idade , Fraturas Cominutivas/patologia , Adulto , Idoso , Feminino , Fraturas do Fêmur/patologia
4.
Development ; 147(6)2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32108026

RESUMO

Reliance on rodents for understanding pancreatic genetics, development and islet function could limit progress in developing interventions for human diseases such as diabetes mellitus. Similarities of pancreas morphology and function suggest that porcine and human pancreas developmental biology may have useful homologies. However, little is known about pig pancreas development. To fill this knowledge gap, we investigated fetal and neonatal pig pancreas at multiple, crucial developmental stages using modern experimental approaches. Purification of islet ß-, α- and δ-cells followed by transcriptome analysis (RNA-seq) and immunohistology identified cell- and stage-specific regulation, and revealed that pig and human islet cells share characteristic features that are not observed in mice. Morphometric analysis also revealed endocrine cell allocation and architectural similarities between pig and human islets. Our analysis unveiled scores of signaling pathways linked to native islet ß-cell functional maturation, including evidence of fetal α-cell GLP-1 production and signaling to ß-cells. Thus, the findings and resources detailed here show how pig pancreatic islet studies complement other systems for understanding the developmental programs that generate functional islet cells, and that are relevant to human pancreatic diseases.


Assuntos
Diferenciação Celular/genética , Células Secretoras de Insulina/fisiologia , Ilhotas Pancreáticas/embriologia , Ilhotas Pancreáticas/crescimento & desenvolvimento , Suínos , Animais , Animais Recém-Nascidos , Células Cultivadas , Embrião de Mamíferos , Feminino , Feto/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Células Secretoras de Glucagon/citologia , Células Secretoras de Glucagon/fisiologia , Humanos , Ilhotas Pancreáticas/citologia , Camundongos , Organogênese/genética , Gravidez , Suínos/embriologia , Suínos/genética , Suínos/crescimento & desenvolvimento , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma
5.
Gastroenterol Hepatol ; 46(1): 69-79, 2023 Jan.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36179947

RESUMO

Endoscopic retrograde cholangiopancreatography (ERCP) is the technique of choice for the treatment of biliopancreatic pathology. However, fluoroscopic imaging does not always allow an adequate diagnosis. On the other hand, some large stones cannot be removed by the usual methods. In these situations, cholangioscopy has proven to be an essential tool for the diagnosis of biliary strictures and the treatment of large stones. Its role in pancreatic pathology is also increasing. The development of a single-operator, disposable cholangioscope has made it possible to expand the technique to a large number of hospitals that perform ERCP. For this reason, the Spanish Society of Digestive Endoscopy has developed this consensus document on the use of the Spyglass-DS cholangioscope. The document has been prepared by a group of endoscopists with expertise in cholangioscopy, reviewing the scientific evidence on the main current indications for cholangiopancreatoscopy.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Colestase , Humanos , Consenso , Colangiopancreatografia Retrógrada Endoscópica/métodos , Endoscopia Gastrointestinal , Pâncreas
6.
Am J Obstet Gynecol ; 227(1): 72.e1-72.e16, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35398029

RESUMO

BACKGROUND: Spontaneous preterm birth remains the main driver of childhood morbidity and mortality. Because of an incomplete understanding of the molecular pathways that result in spontaneous preterm birth, accurate predictive markers and target therapeutics remain elusive. OBJECTIVE: This study sought to determine if a cell-free RNA profile could reveal a molecular signature in maternal blood months before the onset of spontaneous preterm birth. STUDY DESIGN: Maternal samples (n=242) were obtained from a prospective cohort of individuals with a singleton pregnancy across 4 clinical sites at 12-24 weeks (nested case-control; n=46 spontaneous preterm birth <35 weeks and n=194 term controls). Plasma was processed via a next-generation sequencing pipeline for cell-free RNA using the Mirvie RNA platform. Transcripts that were differentially expressed in next-generation sequencing cases and controls were identified. Enriched pathways were identified in the Reactome database using overrepresentation analysis. RESULTS: Twenty five transcripts associated with an increased risk of spontaneous preterm birth were identified. A logistic regression model was developed using these transcripts to predict spontaneous preterm birth with an area under the curve =0.80 (95% confidence interval, 0.72-0.87) (sensitivity=0.76, specificity=0.72). The gene discovery and model were validated through leave-one-out cross-validation. A unique set of 39 genes was identified from cases of very early spontaneous preterm birth (<25 weeks, n=14 cases with time to delivery of 2.5±1.8 weeks); a logistic regression classifier on the basis of these genes yielded an area under the curve=0.76 (95% confidence interval, 0.63-0.87) in leave-one-out cross validation. Pathway analysis for the transcripts associated with spontaneous preterm birth revealed enrichment of genes related to collagen or the extracellular matrix in those who ultimately had a spontaneous preterm birth at <35 weeks. Enrichment for genes in insulin-like growth factor transport and amino acid metabolism pathways were associated with spontaneous preterm birth at <25 weeks. CONCLUSION: Second trimester cell-free RNA profiles in maternal blood provide a noninvasive window to future occurrence of spontaneous preterm birth. The systemic finding of changes in collagen and extracellular matrix pathways may serve to identify individuals at risk for premature cervical remodeling, with growth factor and metabolic pathways implicated more often in very early spontaneous preterm birth. The use of cell-free RNA profiles has the potential to accurately identify those at risk for spontaneous preterm birth by revealing the underlying pathophysiology, creating an opportunity for more targeted therapeutics and effective interventions.


Assuntos
Ácidos Nucleicos Livres , Nascimento Prematuro , Ácidos Nucleicos Livres/genética , Colo do Útero , Feminino , Humanos , Recém-Nascido , Gravidez , Nascimento Prematuro/genética , Estudos Prospectivos , RNA
7.
Proc Natl Acad Sci U S A ; 114(36): 9623-9628, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28830999

RESUMO

Blood circulates throughout the human body and contains molecules drawn from virtually every tissue, including the microbes and viruses which colonize the body. Through massive shotgun sequencing of circulating cell-free DNA from the blood, we identified hundreds of new bacteria and viruses which represent previously unidentified members of the human microbiome. Analyzing cumulative sequence data from 1,351 blood samples collected from 188 patients enabled us to assemble 7,190 contiguous regions (contigs) larger than 1 kbp, of which 3,761 are novel with little or no sequence homology in any existing databases. The vast majority of these novel contigs possess coding sequences, and we have validated their existence both by finding their presence in independent experiments and by performing direct PCR amplification. When their nearest neighbors are located in the tree of life, many of the organisms represent entirely novel taxa, showing that microbial diversity within the human body is substantially broader than previously appreciated.


Assuntos
Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/genética , DNA Bacteriano/sangue , DNA Bacteriano/genética , DNA Viral/sangue , DNA Viral/genética , Microbiota/genética , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Metagenômica/métodos , Filogenia
8.
Eur J Haematol ; 102(5): 389-394, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30719772

RESUMO

OBJECTIVE: The presence of plasmacytomas (Ps) in patients with multiple myeloma (MM) is associated with a poor outcome, both in patients treated conventionally and in patients treated with novel agents. Two types of plasmacytomas have being recognized: paraskeletal plasmacytomas (PPs) and extramedullary plasmacytomas (EMPs), being the incidence of EMPs lower but with worse prognosis. Our aim has been to analyze the efficacy of the pomalidomide-dexamethasone combination in this patient profile. METHOD: In the present study, the efficacy of pomalidomide and dexamethasone in 21 patients from nine hospitals of Catalonia (Spain), with relapsed or refractory MM and Ps, was analyzed. For this purpose, we describe the evolution of paraprotein in serum and urine and the size of plasmacytomas during treatment with pomalidomide-dexamethasone. RESULTS: While 34% of the patients achieved a paraprotein response, only two patients with PPs (9%) responded (RC and PR). There were no responses among patients with EMPs. The median progression-free survival from the start of treatment with pomalidomide/dexamethasone was only 1.7 months and the median overall survival of 4.5 months. CONCLUSION: In conclusion, pomalidomide and dexamethasone has limited efficacy in patients with advanced MM and soft-tissue plasmacytomas.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mieloma Múltiplo/complicações , Plasmocitoma/complicações , Plasmocitoma/tratamento farmacológico , Neoplasias de Tecidos Moles/complicações , Neoplasias de Tecidos Moles/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Dexametasona/administração & dosagem , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Mieloma Múltiplo/diagnóstico , Recidiva Local de Neoplasia , Plasmocitoma/diagnóstico , Neoplasias de Tecidos Moles/diagnóstico , Talidomida/administração & dosagem , Talidomida/análogos & derivados
9.
Clin Chem ; 64(2): 336-345, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29097507

RESUMO

BACKGROUND: Prenatal diagnosis in pregnancies at risk of single-gene disorders is currently performed using invasive methods such as chorionic villus sampling and amniocentesis. This is in contrast with screening for common aneuploidies, for which noninvasive methods with a single maternal blood sample have become standard clinical practice. METHODS: We developed a protocol for noninvasive prenatal diagnosis of inherited single-gene disorders using droplet digital PCR from circulating cell-free DNA (cfDNA) in maternal plasma. First, the amount of cfDNA and fetal fraction is determined using a panel of TaqMan assays targeting high-variability single-nucleotide polymorphisms. Second, the ratio of healthy and diseased alleles in maternal plasma is quantified using TaqMan assays targeting the mutations carried by the parents. Two validation approaches of the mutation assay are presented. RESULTS: We collected blood samples from 9 pregnancies at risk for different single-gene disorders, including common conditions and rare metabolic disorders. We measured cases at risk of hemophilia, ornithine transcarbamylase deficiency, cystic fibrosis, ß-thalassemia, mevalonate kinase deficiency, acetylcholine receptor deficiency, and DFNB1 nonsyndromic hearing loss. We correctly differentiated affected and unaffected pregnancies (2 affected, 7 unaffected), confirmed by neonatal testing. We successfully measured an affected pregnancy as early as week 11 and with a fetal fraction as low as 3.7% (0.3). CONCLUSIONS: Our method detects single-nucleotide mutations of autosomal recessive diseases as early as the first trimester of pregnancy. This is of importance for metabolic disorders in which early diagnosis can affect management of the disease and reduce complications and anxiety related to invasive testing.


Assuntos
Doenças Genéticas Inatas/diagnóstico , Reação em Cadeia da Polimerase/métodos , Diagnóstico Pré-Natal/métodos , Adulto , Alelos , Ácidos Nucleicos Livres/sangue , Protocolos Clínicos , Feminino , Feto/metabolismo , Genes Recessivos , Doenças Genéticas Inatas/sangue , Doenças Genéticas Inatas/genética , Doenças Genéticas Ligadas ao Cromossomo X/sangue , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/genética , Heterozigoto , Humanos , Mutação , Polimorfismo de Nucleotídeo Único , Gravidez , Reprodutibilidade dos Testes
10.
Clin Chem ; 63(11): 1695-1704, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28904056

RESUMO

BACKGROUND: Plasma cell-free RNA (cfRNA) encompasses a broad spectrum of RNA species that can be derived from both human cells and microbes. Because cfRNA is fragmented and of low concentration, it has been challenging to profile its transcriptome using standard RNA-seq methods. METHODS: We assessed several recently developed RNA-seq methods on cfRNA samples. We then analyzed the dynamic changes of both the human transcriptome and the microbiome of plasma during pregnancy from 60 women. RESULTS: cfRNA reflects a well-orchestrated immune modulation during pregnancy: an up-regulation of antiinflammatory genes and an increased abundance of antimicrobial genes. We observed that the plasma microbiome remained relatively stable during pregnancy. The bacteria Ureaplasma shows an increased prevalence and increased abundance at postpartum, which is likely to be associated with postpartum infection. We demonstrated that cfRNA-seq can be used to monitor viral infections. We detected a number of human pathogens in our patients, including an undiagnosed patient with a high load of human parvovirus B19 virus (B19V), which is known to be a potential cause of complications in pregnancy. CONCLUSIONS: Plasma cfRNA-seq demonstrates the potential to simultaneously monitor immune response and microbial infections during pregnancy.


Assuntos
Infecções/imunologia , Complicações Infecciosas na Gravidez/imunologia , RNA/sangue , Adulto , Feminino , Humanos , Infecções/complicações , Microbiota , Gravidez , RNA/genética , Análise de Sequência de RNA , Transcriptoma
11.
Nucleic Acids Res ; 43(5): 2767-79, 2015 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-25690887

RESUMO

DNA bis-intercalators are widely used in molecular biology with applications ranging from DNA imaging to anticancer pharmacology. Two fundamental aspects of these ligands are the lifetime of the bis-intercalated complexes and their sequence selectivity. Here, we perform single-molecule optical tweezers experiments with the peptide Thiocoraline showing, for the first time, that bis-intercalation is driven by a very slow off-rate that steeply decreases with applied force. This feature reveals the existence of a long-lived (minutes) mono-intercalated intermediate that contributes to the extremely long lifetime of the complex (hours). We further exploit this particularly slow kinetics to determine the thermodynamics of binding and persistence length of bis-intercalated DNA for a given fraction of bound ligand, a measurement inaccessible in previous studies of faster intercalating agents. We also develop a novel single-molecule footprinting technique based on DNA unzipping and determine the preferred binding sites of Thiocoraline with one base-pair resolution. This fast and radiolabelling-free footprinting technique provides direct access to the binding sites of small ligands to nucleic acids without the need of cleavage agents. Overall, our results provide new insights into the binding pathway of bis-intercalators and the reported selectivity might be of relevance for this and other anticancer drugs interfering with DNA replication and transcription in carcinogenic cell lines.


Assuntos
Pegada de DNA/métodos , DNA/metabolismo , Depsipeptídeos/metabolismo , Substâncias Intercalantes/metabolismo , Algoritmos , DNA/química , DNA/genética , Depsipeptídeos/química , Elasticidade , Substâncias Intercalantes/química , Cinética , Ligantes , Modelos Moleculares , Conformação de Ácido Nucleico , Pinças Ópticas , Ligação Proteica , Termodinâmica , Fatores de Tempo
12.
Nucleic Acids Res ; 42(3): 2064-74, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24225314

RESUMO

Single-stranded DNA (ssDNA) plays a major role in several biological processes. It is therefore of fundamental interest to understand how the elastic response and the formation of secondary structures are modulated by the interplay between base pairing and electrostatic interactions. Here we measure force-extension curves (FECs) of ssDNA molecules in optical tweezers set up over two orders of magnitude of monovalent and divalent salt conditions, and obtain its elastic parameters by fitting the FECs to semiflexible models of polymers. For both monovalent and divalent salts, we find that the electrostatic contribution to the persistence length is proportional to the Debye screening length, varying as the inverse of the square root of cation concentration. The intrinsic persistence length is equal to 0.7 nm for both types of salts, and the effectivity of divalent cations in screening electrostatic interactions appears to be 100-fold as compared with monovalent salt, in line with what has been recently reported for single-stranded RNA. Finally, we propose an analysis of the FECs using a model that accounts for the effective thickness of the filament at low salt condition and a simple phenomenological description that quantifies the formation of non-specific secondary structure at low forces.


Assuntos
DNA de Cadeia Simples/química , Pareamento de Bases , Cátions Bivalentes/química , Cátions Monovalentes/química , Elasticidade , Cloreto de Magnésio/química , Cloreto de Sódio/química , Eletricidade Estática
13.
Gastrointest Endosc ; 82(6): 1039-46, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26014960

RESUMO

BACKGROUND AND AIMS: A lumen-apposing, self-expanding metal stent incorporated in an electrocautery-enhanced delivery system for EUS-guided drainage of pancreatic fluid collections (PFCs) recently has become available. The aim of this study was to analyze the safety and clinical effectiveness of this newly developed device in this clinical setting. METHODS: This was a retrospective analysis of all consecutive patients with PFCs who underwent EUS-guided drainage using the study device in 13 European centers. RESULTS: Ninety-three patients with PFCs (80% with complex collections) underwent drainage using the study device. Penetration of the PFC was accomplished directly with the study device in 74.2% of patients, and successful stent placement was accomplished in all but 1 patient, mostly without fluoroscopic assistance. Direct endoscopic necrosectomy (DEN) was carried out in 31 of 52 cases (59.6%) of walled-off necrosis and in 2 of 4 cases (50%) of acute peripancreatic fluid collection. Complete resolution of the PFC was obtained in 86 cases (92.5%), with no recurrence during follow-up. Treatment failure occurred in 6 patients because of persistent infection requiring surgery (n = 3), perforation and massive bleeding caused by the nasocystic drainage catheter (NCDC) (n = 2), and the need for a larger opening to extract large necrotic tissue pieces (n = 1). Major adverse events occurred in 5 patients (perforation and massive bleeding caused by the NCDC in 2 patients, 1 pneumoperitoneum and 1 stent dislodgement during DEN, and 1 postdrainage infection) and were mostly not related to the drainage procedure. CONCLUSIONS: EUS-guided drainage with the electrocautery-enhanced delivery system is a safe, easy to perform, and a highly effective minimally invasive treatment modality for PFCs.


Assuntos
Drenagem/instrumentação , Eletrocoagulação/instrumentação , Endossonografia , Pancreatite/terapia , Stents Metálicos Autoexpansíveis , Ultrassonografia de Intervenção , Adulto , Idoso , Idoso de 80 Anos ou mais , Drenagem/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Suco Pancreático , Estudos Retrospectivos , Resultado do Tratamento
14.
Biophys Rev ; 16(1): 89-107, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38495444

RESUMO

I review recent technological advancements in coupling single-cell transcriptomics with cellular phenotypes including morphology, calcium signaling, and electrophysiology. Single-cell RNA sequencing (scRNAseq) has revolutionized cell type classifications by capturing the transcriptional diversity of cells. A new wave of methods to integrate scRNAseq and biophysical measurements is facilitating the linkage of transcriptomic data to cellular function, which provides physiological insight into cellular states. I briefly discuss critical factors of these phenotypical characterizations such as timescales, information content, and analytical tools. Dedicated sections focus on the integration with cell morphology, calcium imaging, and electrophysiology (patch-seq), emphasizing their complementary roles. I discuss their application in elucidating cellular states, refining cell type classifications, and uncovering functional differences in cell subtypes. To illustrate the practical applications and benefits of these methods, I highlight their use in tissues with excitable cell-types such as the brain, pancreatic islets, and the retina. The potential of combining functional phenotyping with spatial transcriptomics for a detailed mapping of cell phenotypes in situ is explored. Finally, I discuss open questions and future perspectives, emphasizing the need for a shift towards broader accessibility through increased throughput.

15.
bioRxiv ; 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36711922

RESUMO

Altered function and gene regulation of pancreatic islet beta cells is a hallmark of type 2 diabetes (T2D), but a comprehensive understanding of mechanisms driving T2D is still missing. Here we integrate information from measurements of chromatin activity, gene expression and function in single beta cells with genetic association data to identify disease-causal gene regulatory changes in T2D. Using machine learning on chromatin accessibility data from 34 non-diabetic, pre-T2D and T2D donors, we robustly identify two transcriptionally and functionally distinct beta cell subtypes that undergo an abundance shift in T2D. Subtype-defining active chromatin is enriched for T2D risk variants, suggesting a causal contribution of subtype identity to T2D. Both subtypes exhibit activation of a stress-response transcriptional program and functional impairment in T2D, which is likely induced by the T2D-associated metabolic environment. Our findings demonstrate the power of multimodal single-cell measurements combined with machine learning for identifying mechanisms of complex diseases.

16.
Nat Genet ; 55(6): 984-994, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37231096

RESUMO

Dysfunctional pancreatic islet beta cells are a hallmark of type 2 diabetes (T2D), but a comprehensive understanding of the underlying mechanisms, including gene dysregulation, is lacking. Here we integrate information from measurements of chromatin accessibility, gene expression and function in single beta cells with genetic association data to nominate disease-causal gene regulatory changes in T2D. Using machine learning on chromatin accessibility data from 34 nondiabetic, pre-T2D and T2D donors, we identify two transcriptionally and functionally distinct beta cell subtypes that undergo an abundance shift during T2D progression. Subtype-defining accessible chromatin is enriched for T2D risk variants, suggesting a causal contribution of subtype identity to T2D. Both beta cell subtypes exhibit activation of a stress-response transcriptional program and functional impairment in T2D, which is probably induced by the T2D-associated metabolic environment. Our findings demonstrate the power of multimodal single-cell measurements combined with machine learning for characterizing mechanisms of complex diseases.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Humanos , Diabetes Mellitus Tipo 2/genética , Multiômica , Células Secretoras de Insulina/metabolismo , Regulação da Expressão Gênica , Cromatina/metabolismo
17.
Cir Esp ; 90(5): 310-7, 2012 May.
Artigo em Espanhol | MEDLINE | ID: mdl-22480916

RESUMO

INTRODUCTION: The treatment of bile duct calculi associated with cholelithiasis is controversial. The hospital costs could be a decisive factor in choosing between the different therapeutic options. OBJECTIVES: To compare the effectiveness and costs of two options in the treatment of common bile duct calculi: 1) One-stage: Laparoscopic cholecystectomy and bile duct exploration, and 2) Two-stage: sequential endoscopic retrograde cholangiopancreatography and laparoscopic cholecystectomy. MATERIAL AND METHODS: A retrospective, observational study was performed on 49 consecutive patients with bile duct calculi and gallbladder in situ, treated consecutively and simultaneously over a two year period. The post-operate complication, hospital stay, number of procedures per patient, conversion to laparotomy, efficacy of removing the calculi, and hospital costs. RESULTS: There were no differences as regards the patient clinical features or morbidity. The mean post-surgical hospital stay for the One-stage group was less than that in the Two-stage group. Three patients of the Two-stage group required conversion to laparotomy. The median costs per patient were less for the One-stage strategy, representing an overall saving of 37,173€ during the period studied. CONCLUSIONS: No significant differences were found between the two treatment options as regards efficacy or post-surgical morbidity and mortality, but there were differences in hospital stay and costs. The management of patients with gallstones in one-stage surgery represents a saving of 3 days hospital stay and 1,008€ per patient.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/economia , Colecistectomia Laparoscópica/economia , Cálculos Biliares/economia , Cálculos Biliares/cirurgia , Custos Hospitalares/estatística & dados numéricos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
18.
Blood Cancer J ; 12(4): 68, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440057

RESUMO

Infections remain a common complication in patients with multiple myeloma (MM) and are associated with morbidity and mortality. A risk score to predict the probability of early severe infection could help to identify the patients that would benefit from preventive measures. We undertook a post hoc analysis of infections in four clinical trials from the Spanish Myeloma Group, involving a total of 1347 patients (847 transplant candidates). Regarding the GEM2010 > 65 trial, antibiotic prophylaxis was mandatory, so we excluded it from the final analysis. The incidence of severe infection episodes within the first 6 months was 13.8%, and majority of the patients experiencing the first episode before 4 months (11.1%). 1.2% of patients died because of infections within the first 6 months (1% before 4 months). Variables associated with increased risk of severe infection in the first 4 months included serum albumin ≤30 g/L, ECOG > 1, male sex, and non-IgA type MM. A simple risk score with these variables facilitated the identification of three risk groups with different probabilities of severe infection within the first 4 months: low-risk (score 0-2) 8.2%; intermediate-risk (score 3) 19.2%; and high-risk (score 4) 28.3%. Patients with intermediate/high risk could be candidates for prophylactic antibiotic therapies.


Assuntos
Mieloma Múltiplo , Antibioticoprofilaxia , Humanos , Masculino , Mieloma Múltiplo/complicações , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/terapia
19.
Cell Metab ; 34(2): 256-268.e5, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35108513

RESUMO

In diabetes, glucagon secretion from pancreatic α cells is dysregulated. The underlying mechanisms, and whether dysfunction occurs uniformly among cells, remain unclear. We examined α cells from human donors and mice using electrophysiological, transcriptomic, and computational approaches. Rising glucose suppresses α cell exocytosis by reducing P/Q-type Ca2+ channel activity, and this is disrupted in type 2 diabetes (T2D). Upon high-fat feeding of mice, α cells shift toward a "ß cell-like" electrophysiological profile in concert with indications of impaired identity. In human α cells we identified links between cell membrane properties and cell surface signaling receptors, mitochondrial respiratory chain complex assembly, and cell maturation. Cell-type classification using machine learning of electrophysiology data demonstrated a heterogenous loss of "electrophysiologic identity" in α cells from donors with type 2 diabetes. Indeed, a subset of α cells with impaired exocytosis is defined by an enrichment in progenitor and lineage markers and upregulation of an immature transcriptomic phenotype, suggesting important links between α cell maturation state and dysfunction.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Glucagon , Ilhotas Pancreáticas , Animais , Diabetes Mellitus Tipo 2/metabolismo , Exocitose/fisiologia , Glucagon/metabolismo , Células Secretoras de Glucagon/metabolismo , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Camundongos
20.
Rev Esp Enferm Dig ; 103(4): 204-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21526874

RESUMO

A review is made of the indications of ultrasonographic contrast enhancement as applied to conventional ultrasonography and endocopic ultrasonography (EUS) as opposed to the use of EUS-sonoelastography today.


Assuntos
Meios de Contraste , Doenças do Sistema Digestório/diagnóstico por imagem , Técnicas de Imagem por Elasticidade , Algoritmos , Colangiopancreatografia Retrógrada Endoscópica , Colangiopancreatografia por Ressonância Magnética , Endossonografia , Previsões , Humanos , Sensibilidade e Especificidade , Ultrassonografia de Intervenção
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