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1.
Proc Natl Acad Sci U S A ; 119(44): e2209743119, 2022 11.
Article in English | MEDLINE | ID: mdl-36279429

ABSTRACT

Allopolyploidization, resulting in divergent genomes in the same cell, is believed to trigger a "genome shock", leading to broad genetic and epigenetic changes. However, little is understood about chromatin and gene-expression dynamics as underlying driving forces during allopolyploidization. Here, we examined the genome-wide DNase I-hypersensitive site (DHS) and its variations in domesticated allotetraploid cotton (Gossypium hirsutum and Gossypium barbadense, AADD) and its extant AA (Gossypium arboreum) and DD (Gossypium raimondii) progenitors. We observed distinct DHS distributions between G. arboreum and G. raimondii. In contrast, the DHSs of the two subgenomes of G. hirsutum and G. barbadense showed a convergent distribution. This convergent distribution of DHS was also present in the wild allotetraploids Gossypium darwinii and G. hirsutum var. yucatanense, but absent from a resynthesized hybrid of G. arboreum and G. raimondii, suggesting that it may be a common feature in polyploids, and not a consequence of domestication after polyploidization. We revealed that putative cis-regulatory elements (CREs) derived from polyploidization-related DHSs were dominated by several families, including Dof, ERF48, and BPC1. Strikingly, 56.6% of polyploidization-related DHSs were derived from transposable elements (TEs). Moreover, we observed positive correlations between DHS accessibility and the histone marks H3K4me3, H3K27me3, H3K36me3, H3K27ac, and H3K9ac, indicating that coordinated interplay among histone modifications, TEs, and CREs drives the DHS landscape dynamics under polyploidization. Collectively, these findings advance our understanding of the regulatory architecture in plants and underscore the complexity of regulome evolution during polyploidization.


Subject(s)
Gossypium , Histones , Chromatin/genetics , Deoxyribonuclease I , DNA Transposable Elements , Gossypium/genetics , Histones/genetics
2.
Adv Exp Med Biol ; 3234: 89-107, 2024.
Article in English | MEDLINE | ID: mdl-38507202

ABSTRACT

Cellular machines formed by the interaction and assembly of macromolecules are essential in many processes of the living cell. These assemblies involve homo- and hetero-associations, including protein-protein, protein-DNA, protein-RNA, and protein-polysaccharide associations, most of which are reversible. This chapter describes the use of analytical ultracentrifugation, light scattering, and fluorescence-based methods, well-established biophysical techniques, to characterize interactions leading to the formation of macromolecular complexes and their modulation in response to specific or unspecific factors. We also illustrate, with several examples taken from studies on bacterial processes, the advantages of the combined use of subsets of these techniques as orthogonal analytical methods to analyze protein oligomerization and polymerization, interactions with ligands, hetero-associations involving membrane proteins, and protein-nucleic acid complexes.


Subject(s)
Proteins , RNA , Spectrometry, Fluorescence , Proteins/chemistry , Macromolecular Substances , Ultracentrifugation/methods
3.
Proc Natl Acad Sci U S A ; 118(33)2021 08 17.
Article in English | MEDLINE | ID: mdl-34385324

ABSTRACT

As phosphorus is one of the most limiting nutrients in many natural and agricultural ecosystems, plants have evolved strategies that cope with its scarcity. Genetic approaches have facilitated the identification of several molecular elements that regulate the phosphate (Pi) starvation response (PSR) of plants, including the master regulator of the transcriptional response to phosphate starvation PHOSPHATE STARVATION RESPONSE1 (PHR1). However, the chromatin modifications underlying the plant transcriptional response to phosphate scarcity remain largely unknown. Here, we present a detailed analysis of changes in chromatin accessibility during phosphate starvation in Arabidopsis thaliana root cells. Root cells undergo a genome-wide remodeling of chromatin accessibility in response to Pi starvation that is often associated with changes in the transcription of neighboring genes. Analysis of chromatin accessibility in the phr1 phl2 double mutant revealed that the transcription factors PHR1 and PHL2 play a key role in remodeling chromatin accessibility in response to Pi limitation. We also discovered that PHR1 and PHL2 play an important role in determining chromatin accessibility and the associated transcription of many genes under optimal Pi conditions, including genes involved in the PSR. We propose that a set of transcription factors directly activated by PHR1 in Pi-starved root cells trigger a second wave of epigenetic changes required for the transcriptional activation of the complete set of low-Pi-responsive genes.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/metabolism , Gene Expression Regulation, Plant/drug effects , Genome, Plant , Phosphates/administration & dosage , Phosphates/pharmacology , Transcription Factors/metabolism , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Chromatin/metabolism , Phosphates/metabolism , Plant Roots/cytology , Transcription Factors/genetics
4.
Circulation ; 146(16): e229-e241, 2022 10 18.
Article in English | MEDLINE | ID: mdl-36120864

ABSTRACT

Academic medicine as a practice model provides unique benefits to society. Clinical care remains an important part of the academic mission; however, equally important are the educational and research missions. More specifically, the sustainability of health care in the United States relies on an educated and expertly trained physician workforce directly provided by academic medicine models. Similarly, the research charge to deliver innovation and discovery to improve health care and to cure disease is key to academic missions. Therefore, to support and promote the growth and sustainability of academic medicine, attracting and engaging top talent from fellows in training and early career faculty is of vital importance. However, as the health care needs of the nation have risen, clinicians have experienced unprecedented demand, and individual wellness and burnout have been examined more closely. Here, we provide a close look at the unique drivers of burnout in academic cardiovascular medicine and propose system-level and personal interventions to support individual wellness in this model.


Subject(s)
Burnout, Professional , Medicine , Physicians , American Heart Association , Burnout, Professional/prevention & control , Delivery of Health Care , Humans , United States
5.
Cell Commun Signal ; 21(1): 30, 2023 02 03.
Article in English | MEDLINE | ID: mdl-36737758

ABSTRACT

BACKGROUND: C3G is a guanine nucleotide exchange factor (GEF) that activates Rap1 to promote cell adhesion. Resting C3G is autoinhibited and the GEF activity is released by stimuli that signal through tyrosine kinases. C3G is activated by tyrosine phosphorylation and interaction with Crk adaptor proteins, whose expression is elevated in multiple human cancers. However, the molecular details of C3G activation and the interplay between phosphorylation and Crk interaction are poorly understood. METHODS: We combined biochemical, biophysical, and cell biology approaches to elucidate the mechanisms of C3G activation. Binding of Crk adaptor proteins to four proline-rich motifs (P1 to P4) in C3G was characterized in vitro using isothermal titration calorimetry and sedimentation velocity, and in Jurkat and HEK293T cells by affinity pull-down assays. The nucleotide exchange activity of C3G over Rap1 was measured using nucleotide-dissociation kinetic assays. Jurkat cells were also used to analyze C3G translocation to the plasma membrane and the C3G-dependent activation of Rap1 upon ligation of T cell receptors. RESULTS: CrkL interacts through its SH3N domain with sites P1 and P2 of inactive C3G in vitro and in Jurkat and HEK293T cells, and these sites are necessary to recruit C3G to the plasma membrane. However, direct stimulation of the GEF activity requires binding of Crk proteins to the P3 and P4 sites. P3 is occluded in resting C3G and is essential for activation, while P4 contributes secondarily towards complete stimulation. Tyrosine phosphorylation of C3G alone causes marginal activation. Instead, phosphorylation primes C3G lowering the concentration of Crk proteins required for activation and increasing the maximum activity. Unexpectedly, optimal activation also requires the interaction of CrkL-SH2 domain with phosphorylated C3G. CONCLUSION: Our study revealed that phosphorylation of C3G by Src and Crk-binding form a two-factor mechanism that ensures tight control of C3G activation. Additionally, the simultaneous SH2 and SH3N interaction of CrkL with C3G, required for the activation, reveals a novel adaptor-independent function of Crk proteins relevant to understanding their role in physiological signaling and their deregulation in diseases. Video abstract.


Subject(s)
Guanine Nucleotide-Releasing Factor 2 , Nuclear Proteins , Humans , Guanine Nucleotide Exchange Factors/metabolism , Guanine Nucleotide-Releasing Factor 2/metabolism , HEK293 Cells , Nuclear Proteins/metabolism , Nucleotides/metabolism , Proto-Oncogene Proteins c-crk/metabolism , src Homology Domains , Tyrosine/metabolism
6.
Biochemistry ; 61(22): 2482-2489, 2022 11 15.
Article in English | MEDLINE | ID: mdl-36315857

ABSTRACT

Dynamic biomolecular condensates formed by liquid-liquid phase separation can regulate the spatial and temporal organization of proteins, thus modulating their functional activity in cells. Previous studies showed that the cell division protein FtsZ from Escherichia coli formed dynamic phase-separated condensates with nucleoprotein complexes containing the FtsZ spatial regulator SlmA under crowding conditions, with potential implications for condensate-mediated spatiotemporal control of FtsZ activity in cell division. In the present study, we assessed formation of these condensates in the presence of lipid surfaces and glutamate ions to better approximate the E. coli intracellular environment. We found that potassium glutamate substantially promoted the formation of FtsZ-containing condensates when compared to potassium chloride in crowded solutions. These condensates accumulated on supported lipid bilayers and eventually fused, resulting in a time-dependent increase in the droplet size. Moreover, the accumulated condensates were dynamic, capturing protein from the external phase. FtsZ partitioned into the condensates at the lipid surface only in its guanosine diphosphate (GDP) form, regardless of whether it came from FtsZ polymer disassembly upon guanosine triphosphate (GTP) exhaustion. These results provide insights into the behavior of these GTP-responsive condensates in minimal membrane systems, which suggest how these membraneless assemblies may tune critical bacterial division events during the cell cycle.


Subject(s)
Carrier Proteins , Cytoskeletal Proteins , Escherichia coli Proteins , Anions/metabolism , Biomolecular Condensates , Carrier Proteins/metabolism , Cell Division , Cytoskeletal Proteins/metabolism , DNA/metabolism , Escherichia coli/metabolism , Escherichia coli Proteins/metabolism , Glutamic Acid/metabolism , Guanosine Triphosphate/metabolism , Lipid Bilayers/metabolism
7.
J Biol Chem ; 297(3): 101039, 2021 09.
Article in English | MEDLINE | ID: mdl-34343569

ABSTRACT

Hereditary transthyretin amyloidosis (ATTR) is an autosomal dominant disease characterized by the extracellular deposition of the transport protein transthyretin (TTR) as amyloid fibrils. Despite the progress achieved in recent years, understanding why different TTR residue substitutions lead to different clinical manifestations remains elusive. Here, we studied the molecular basis of disease-causing missense mutations affecting residues R34 and K35. R34G and K35T variants cause vitreous amyloidosis, whereas R34T and K35N mutations result in amyloid polyneuropathy and restrictive cardiomyopathy. All variants are more sensitive to pH-induced dissociation and amyloid formation than the wild-type (WT)-TTR counterpart, specifically in the variants deposited in the eyes amyloid formation occurs close to physiological pHs. Chemical denaturation experiments indicate that all the mutants are less stable than WT-TTR, with the vitreous amyloidosis variants, R34G and K35T, being highly destabilized. Sequence-induced stabilization of the dimer-dimer interface with T119M rendered tetramers containing R34G or K35T mutations resistant to pH-induced aggregation. Because R34 and K35 are among the residues more distant to the TTR interface, their impact in this region is therefore theorized to occur at long range. The crystal structures of double mutants, R34G/T119M and K35T/T119M, together with molecular dynamics simulations indicate that their strong destabilizing effect is initiated locally at the BC loop, increasing its flexibility in a mutation-dependent manner. Overall, the present findings help us to understand the sequence-dynamic-structural mechanistic details of TTR amyloid aggregation triggered by R34 and K35 variants and to link the degree of mutation-induced conformational flexibility to protein aggregation propensity.


Subject(s)
Amyloid Neuropathies, Familial/genetics , Mutation, Missense , Prealbumin/chemistry , Prealbumin/genetics , Amyloid Neuropathies, Familial/metabolism , Humans , Kinetics , Molecular Dynamics Simulation , Prealbumin/metabolism , Protein Aggregates , Protein Conformation, alpha-Helical , Protein Stability , Thermodynamics
8.
FASEB J ; 35(8): e21815, 2021 08.
Article in English | MEDLINE | ID: mdl-34314064

ABSTRACT

The Src homology 2 containing inositol 5-phosphatase 2 (SHIP2) is a large multidomain enzyme that catalyzes the dephosphorylation of the phospholipid phosphatidylinositol 3,4,5-triphosphate (PI(3,4,5)P3 ) to form PI(3,4)P2 . PI(3,4,5)P3 is a key lipid second messenger controlling the recruitment of signaling proteins to the plasma membrane, thereby regulating a plethora of cellular events, including proliferation, growth, apoptosis, and cytoskeletal rearrangements. SHIP2, alongside PI3K and PTEN, regulates PI(3,4,5)P3 levels at the plasma membrane and has been heavily implicated in serious diseases such as cancer and type 2 diabetes; however, many aspects of its regulation mechanism remain elusive. We recently reported an activating effect of the SHIP2 C2 domain and here we describe an additional layer of regulation via the pleckstrin homology-related (PHR) domain. We show a phosphoinositide-induced transition to a high activity state of the enzyme that increases phosphatase activity up to 10-15 fold. We further show that PI(3,4)P2 directly interacts with the PHR domain to trigger this allosteric activation. Modeling of the PHR-phosphatase-C2 region of SHIP2 on the membrane suggests no major inter-domain interactions with the PHR domain, but close contacts between the two linkers offer a possible path of allosteric communication. Together, our data show that the PHR domain acts as an allosteric module regulating the catalytic activity of SHIP2 in response to specific phosphoinositide levels in the cell membrane.


Subject(s)
Cell Membrane/metabolism , Phosphatidylinositol Phosphates/metabolism , Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases , Pleckstrin Homology Domains , Allosteric Regulation , Biocatalysis , Humans , Models, Molecular , Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases/chemistry , Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases/metabolism
9.
Nucleic Acids Res ; 48(14): 8113-8127, 2020 08 20.
Article in English | MEDLINE | ID: mdl-32658272

ABSTRACT

Quorum sensing allows bacterial cells to communicate through the release of soluble signaling molecules into the surrounding medium. It plays a pivotal role in controlling bacterial conjugation in Gram-positive cells, a process that has tremendous impact on health. Intracellular regulatory proteins of the RRNPP family are common targets of these signaling molecules. The RRNPP family of gene regulators bind signaling molecules at their C-terminal domain (CTD), but have highly divergent functionalities at their N-terminal effector domains (NTD). This divergence is also reflected in the functional states of the proteins, and is highly interesting from an evolutionary perspective. RappLS20 is an RRNPP encoded on the Bacillus subtilis plasmid pLS20. It relieves the gene repression effectuated by RcopLS20 in the absence of the mature pLS20 signaling peptide Phr*pLS20. We report here an in-depth structural study of apo and Phr*pLS20-bound states of RappLS20 at various levels of atomic detail. We show that apo-RappLS20 is dimeric and that Phr*pLS20-bound Rap forms NTD-mediated tetramers. In addition, we show that RappLS20 binds RcopLS20 directly in the absence of Phr*pLS20 and that addition of Phr*pLS20 releases RcopLS20 from RappLS20. This allows RcopLS20 to bind the promotor region of crucial conjugation genes blocking their expression.


Subject(s)
Bacterial Proteins/metabolism , Gene Expression Regulation, Bacterial , Operon , Protein Multimerization , Trans-Activators/metabolism , Bacillus subtilis , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Conjugation, Genetic/genetics , Peptides/metabolism , Promoter Regions, Genetic , Tetratricopeptide Repeat , Trans-Activators/chemistry , Trans-Activators/genetics
10.
Nucleic Acids Res ; 48(19): 10785-10801, 2020 11 04.
Article in English | MEDLINE | ID: mdl-33045732

ABSTRACT

Quorum sensing plays crucial roles in bacterial communication including in the process of conjugation, which has large economical and health-related impacts by spreading antibiotic resistance. The conjugative Bacillus subtilis plasmid pLS20 uses quorum sensing to determine when to activate the conjugation genes. The main conjugation promoter, Pc, is by default repressed by a regulator RcopLS20 involving DNA looping. A plasmid-encoded signalling peptide, Phr*pLS20, inactivates the anti-repressor of RcopLS20, named RappLS20, which belongs to the large group of RRNPP family of regulatory proteins. Here we show that DNA looping occurs through interactions between two RcopLS20 tetramers, each bound to an operator site. We determined the relative promoter strengths for all the promoters involved in synthesizing the regulatory proteins of the conjugation genes, and constructed an in vivo system uncoupling these regulatory genes to show that RappLS20 is sufficient for activating conjugation in vivo. We also show that RappLS20 actively detaches RcopLS20 from DNA by preferentially acting on the RcopLS20 molecules involved in DNA looping, resulting in sequestration but not inactivation of RcopLS20. Finally, results presented here in combination with our previous results show that activation of conjugation inhibits competence and competence development inhibits conjugation, indicating that both processes are mutually exclusive.


Subject(s)
Bacillus subtilis/genetics , Bacterial Proteins/genetics , Conjugation, Genetic , Gene Expression Regulation, Bacterial , Quorum Sensing , Bacillus subtilis/metabolism , Bacillus subtilis/physiology , Bacterial Proteins/metabolism , Plasmids/genetics , Promoter Regions, Genetic
11.
Nucleic Acids Res ; 47(12): 6519-6537, 2019 07 09.
Article in English | MEDLINE | ID: mdl-31114891

ABSTRACT

Human mitochondrial DNA (h-mtDNA) codes for 13 subunits of the oxidative phosphorylation pathway, the essential route that produces ATP. H-mtDNA transcription and replication depends on the transcription factor TFAM, which also maintains and compacts this genome. It is well-established that TFAM activates the mtDNA promoters LSP and HSP1 at the mtDNA control region where DNA regulatory elements cluster. Previous studies identified still uncharacterized, additional binding sites at the control region downstream from and slightly similar to LSP, namely sequences X and Y (Site-X and Site-Y) (Fisher et al., Cell 50, pp 247-258, 1987). Here, we explore TFAM binding at these two sites and compare them to LSP by multiple experimental and in silico methods. Our results show that TFAM binding is strongly modulated by the sequence-dependent properties of Site-X, Site-Y and LSP. The high binding versatility of Site-Y or the considerable stiffness of Site-X tune TFAM interactions. In addition, we show that increase in TFAM/DNA complex concentration induces multimerization, which at a very high concentration triggers disruption of preformed complexes. Therefore, our results suggest that mtDNA sequences induce non-uniform TFAM binding and, consequently, direct an uneven distribution of TFAM aggregation sites during the essential process of mtDNA compaction.


Subject(s)
DNA, Mitochondrial/chemistry , DNA, Mitochondrial/metabolism , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , Mitochondrial Proteins/chemistry , Mitochondrial Proteins/metabolism , Transcription Factors/chemistry , Transcription Factors/metabolism , Base Sequence , Humans , Poly A , Promoter Regions, Genetic , Protein Binding , Protein Multimerization , Thermodynamics
12.
Nucleic Acids Res ; 46(22): 11910-11926, 2018 12 14.
Article in English | MEDLINE | ID: mdl-30380104

ABSTRACT

The principal route for dissemination of antibiotic resistance genes is conjugation by which a conjugative DNA element is transferred from a donor to a recipient cell. Conjugative elements contain genes that are important for their establishment in the new host, for instance by counteracting the host defense mechanisms acting against incoming foreign DNA. Little is known about these establishment genes and how they are regulated. Here, we deciphered the regulation mechanism of possible establishment genes of plasmid p576 from the Gram-positive bacterium Bacillus pumilus. Unlike the ssDNA promoters described for some conjugative plasmids, the four promoters of these p576 genes are repressed by a repressor protein, which we named Reg576. Reg576 also regulates its own expression. After transfer of the DNA, these genes are de-repressed for a period of time until sufficient Reg576 is synthesized to repress the promoters again. Complementary in vivo and in vitro analyses showed that different operator configurations in the promoter regions of these genes lead to different responses to Reg576. Each operator is bound with extreme cooperativity by two Reg576-dimers. The X-ray structure revealed that Reg576 has a Ribbon-Helix-Helix core and provided important insights into the high cooperativity of DNA recognition.


Subject(s)
Bacillus pumilus/genetics , Bacterial Proteins/chemistry , DNA/chemistry , Gene Transfer, Horizontal , Plasmids/chemistry , Repressor Proteins/chemistry , Bacillus pumilus/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Base Sequence , Binding Sites , Cloning, Molecular , Conjugation, Genetic , DNA/genetics , DNA/metabolism , Drug Resistance, Multiple, Bacterial/genetics , Escherichia coli/genetics , Escherichia coli/metabolism , Gene Expression , Gene Expression Regulation, Bacterial , Genetic Vectors/chemistry , Genetic Vectors/metabolism , Nucleic Acid Conformation , Plasmids/metabolism , Promoter Regions, Genetic , Protein Binding , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Interaction Domains and Motifs , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Repressor Proteins/genetics , Repressor Proteins/metabolism , Shigella flexneri/genetics , Shigella flexneri/metabolism
13.
PLoS Genet ; 13(2): e1006586, 2017 02.
Article in English | MEDLINE | ID: mdl-28207825

ABSTRACT

Antibiotic resistance is a serious global problem. Antibiotic resistance genes (ARG), which are widespread in environmental bacteria, can be transferred to pathogenic bacteria via horizontal gene transfer (HGT). Gut microbiomes are especially apt for the emergence and dissemination of ARG. Conjugation is the HGT route that is predominantly responsible for the spread of ARG. Little is known about conjugative elements of Gram-positive bacteria, including those of the phylum Firmicutes, which are abundantly present in gut microbiomes. A critical step in the conjugation process is the relaxase-mediated site- and strand-specific nick in the oriT region of the conjugative element. This generates a single-stranded DNA molecule that is transferred from the donor to the recipient cell via a connecting channel. Here we identified and characterized the relaxosome components oriT and the relaxase of the conjugative plasmid pLS20 of the Firmicute Bacillus subtilis. We show that the relaxase gene, named relLS20, is essential for conjugation, that it can function in trans and provide evidence that Tyr26 constitutes the active site residue. In vivo and in vitro analyses revealed that the oriT is located far upstream of the relaxase gene and that the nick site within oriT is located on the template strand of the conjugation genes. Surprisingly, the RelLS20 shows very limited similarity to known relaxases. However, more than 800 genes to which no function had been attributed so far are predicted to encode proteins showing significant similarity to RelLS20. Interestingly, these putative relaxases are encoded almost exclusively in Firmicutes bacteria. Thus, RelLS20 constitutes the prototype of a new family of relaxases. The identification of this novel relaxase family will have an important impact in different aspects of future research in the field of HGT in Gram-positive bacteria in general, and specifically in the phylum of Firmicutes, and in gut microbiome research.


Subject(s)
Bacterial Proteins/genetics , Conjugation, Genetic , Drug Resistance, Bacterial/genetics , Endodeoxyribonucleases/genetics , Firmicutes/enzymology , Amino Acid Sequence , Bacillus subtilis/enzymology , DNA, Single-Stranded/genetics , Endodeoxyribonucleases/isolation & purification , Firmicutes/genetics , Gastrointestinal Microbiome/genetics , Gene Transfer, Horizontal , Humans , Plasmids/genetics
14.
Int J Mol Sci ; 22(1)2020 Dec 22.
Article in English | MEDLINE | ID: mdl-33375200

ABSTRACT

Microbiota is defined as the collection of microorganisms within the gastrointestinal ecosystem. These microbes are strongly implicated in the stimulation of immune responses. An unbalanced microbiota, termed dysbiosis, is related to the development of several liver diseases. The bidirectional relationship between the gut, its microbiota and the liver is referred to as the gut-liver axis. The translocation of bacterial products from the intestine to the liver induces inflammation in different cell types such as Kupffer cells, and a fibrotic response in hepatic stellate cells, resulting in deleterious effects on hepatocytes. Moreover, ischemia-reperfusion injury, a consequence of liver surgery, alters the microbiota profile, affecting inflammation, the immune response and even liver regeneration. Microbiota also seems to play an important role in post-operative outcomes (i.e., liver transplantation or liver resection). Nonetheless, studies to determine changes in the gut microbial populations produced during and after surgery, and affecting liver function and regeneration are scarce. In the present review we analyze and discuss the preclinical and clinical studies reported in the literature focused on the evaluation of alterations in microbiota and its products as well as their effects on post-operative outcomes in hepatic surgery.


Subject(s)
Gastrointestinal Microbiome/physiology , Gastrointestinal Tract/metabolism , Liver Diseases/surgery , Liver Transplantation/methods , Liver/physiology , Animals , Dysbiosis/metabolism , Dysbiosis/microbiology , Dysbiosis/physiopathology , Gastrointestinal Tract/microbiology , Hepatectomy/methods , Humans , Liver Diseases/physiopathology , Reperfusion Injury/metabolism , Reperfusion Injury/microbiology , Reperfusion Injury/physiopathology
15.
Catheter Cardiovasc Interv ; 93(3): 373-379, 2019 02 15.
Article in English | MEDLINE | ID: mdl-30280472

ABSTRACT

BACKGROUND: Despite improvements in acute care and survival after non-ST-elevation acute coronary syndrome (NSTE-ACS) hospitalization, early readmissions remain common, and have significant clinical and financial impact. OBJECTIVES: Determine the predictors and etiologies of 30-day readmissions in NSTE-ACS. METHOD: The study cohort was derived from the National Readmission Database 2014 identifying patients with a primary diagnosis of NSTE-ACS using ICD9 code. RESULTS: We identified a total of 300,269 patients admitted with NSTE-ACS; 13.4% were readmitted within 30-day. The most common cause of readmission was heart failure (HF) (15.6%), followed by a recurrent myocardial infarction (MI) (10%). Predictors of increased readmissions were age ≥ 75 years (OR: 1.34, 95% CI: 1.30-1.39), female gender (OR 1.12, 95% CI 1.09-1.16), a Charlson Comorbidity Index (CCI) >3 (OR 2.11, 95% CI: 2.04-2.18), ESRD (OR 2.01, 95% CI 1.89-2.14), CKD (OR: 1.58, 95% CI: 1.51-1.64), length of stay ≥5 days (OR: 1.51, 95% CI 1.46-1.56) and adverse events during the index admission such as AKI (OR:1.31, 95% CI: 1.25-1.36), major bleeding (OR:1.20, 95% CI: 1.12-1.24); whereas admission to a teaching hospital (OR 0.92, 95% CI 0.89-0.95) and PCI (OR 0.70, 95% CI 0.67-0.72) were associated with less likelihood of 30-day readmission. CONCLUSION: Readmission rate at 30-days is high among NSTE-ACS patients and the most common readmission etiologies are HF and recurrent MI. A CCI more than 3 and ESRD were the most significant predictors for readmission; patients undergoing PCI had less odds of readmission.


Subject(s)
Acute Coronary Syndrome/therapy , Cardiovascular Agents/therapeutic use , Coronary Artery Bypass , Heart Failure/therapy , Non-ST Elevated Myocardial Infarction/therapy , Patient Readmission , Percutaneous Coronary Intervention , Acute Coronary Syndrome/diagnosis , Acute Coronary Syndrome/epidemiology , Adolescent , Adult , Aged , Cardiovascular Agents/adverse effects , Comorbidity , Databases, Factual , Female , Heart Failure/diagnosis , Heart Failure/epidemiology , Humans , Kidney Failure, Chronic/epidemiology , Male , Middle Aged , Non-ST Elevated Myocardial Infarction/diagnosis , Non-ST Elevated Myocardial Infarction/epidemiology , Percutaneous Coronary Intervention/adverse effects , Recurrence , Retrospective Studies , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome , United States/epidemiology , Young Adult
16.
Catheter Cardiovasc Interv ; 94(4): 578-587, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-30790415

ABSTRACT

BACKGROUND: Pulseless ventricular tachycardia/ventricular fibrillation (VT/VF) is the initial rhythm in a third of in-hospital cardiac arrest patients. Mechanical circulatory support (MCS) device use remains poorly understood in this population. METHODS: We conducted an observational analysis of temporal trends in the utilization of MCS in VT/VF IHCA between January 2008 and December 2014 utilizing the Nationwide Inpatient Sample (NIS) database. Using multivariable analysis, we assessed factors associated with MCS use and survival to discharge. RESULTS: Among 151,628 hospitalizations with VT/VF IHCA, 14,981 (9.9%) received MCS. Intra-aortic balloon pump (IABP) was the most commonly used MCS (9.1%). From 2008 to 2014, there was significant increase in the utilization of MCS (8.7-11%; ptrend < 0.0001). On multivariable analysis, there was 12-fold increase and three-fold increase in the utilization of PVAD and ECMO respectively; however, there was no significant change in the use of IABP. Over the seven-year sample period, there was significant increase in the overall survival to hospital discharge (35.4-43.5%; ptrend < 0.0001). Survival to hospital discharge increased in both MCS and non-MCS groups. CONCLUSION: There was significant increase in utilization of MCS after VT/VF IHCA during the study period. IABP was the most commonly utilized MCS. The survival to hospital discharge increased in the overall study population including both MCS and non-MCS groups. Future studies are needed to identify patient population most likely to benefit from the use of MCS after VT/VF IHCA.


Subject(s)
Extracorporeal Membrane Oxygenation/trends , Heart Arrest/therapy , Heart-Assist Devices/trends , Intra-Aortic Balloon Pumping/trends , Oxygenators, Membrane/trends , Practice Patterns, Physicians'/trends , Tachycardia, Ventricular/complications , Ventricular Fibrillation/complications , Aged , Aged, 80 and over , Databases, Factual , Extracorporeal Membrane Oxygenation/adverse effects , Extracorporeal Membrane Oxygenation/instrumentation , Extracorporeal Membrane Oxygenation/mortality , Female , Heart Arrest/etiology , Heart Arrest/mortality , Heart Arrest/physiopathology , Humans , Intra-Aortic Balloon Pumping/adverse effects , Intra-Aortic Balloon Pumping/instrumentation , Intra-Aortic Balloon Pumping/mortality , Male , Middle Aged , Risk Factors , Tachycardia, Ventricular/mortality , Tachycardia, Ventricular/physiopathology , Time Factors , Treatment Outcome , United States , Ventricular Fibrillation/mortality , Ventricular Fibrillation/physiopathology
17.
Pacing Clin Electrophysiol ; 42(7): 846-852, 2019 07.
Article in English | MEDLINE | ID: mdl-30977144

ABSTRACT

BACKGROUND: Complete heart block is a known complication after transcatheter aortic valve replacement (TAVR), often requiring pacemaker implantation within 24 hours of the procedure. However, clinical markers for delayed progression to complete heart block after TAVR remain unclear. OBJECTIVES: We examined electrocardiographic data that may correlate with delayed progression to complete heart block and need for pacemaker. METHODS: This is a single-center retrospective study of 608 patients who underwent TAVR between April 2008 and June 2017. We excluded 164 (27.0%) patients due to having a pacemaker before the procedure or expiring within 24 hours of the procedure (8, 1.3%). We excluded an additional 50 (8.2%) patients who received a pacemaker within 24 hours of the procedure. Electrocardiograms (EKGs) obtained after the procedure were compared to the preprocedural EKG to detect new changes. RESULTS: Left bundle branch block, intraventricular conduction delay, left anterior fascicular block, and right bundle branch block were the most commonly seen conduction abnormalities after TAVR (25.1%, 10.9%, 7.5%, and 3.6%, respectively). Both left bundle branch block (odds ratio [OR] = 2.77 [95% confidence interval (CI): 1.24-6.22]) and right bundle branch block (OR = 13.2 [95% CI: 4.18-41.70]) carried an increased risk of pacemaker implantation after TAVR. Additionally, ΔPR greater than 40 ms from baseline also carried an increased risk of pacemaker implantation (OR = 3.53 [95% CI: 1.49-8.37]). CONCLUSION: Left bundle branch block, right bundle branch block, and ΔPR greater than 40 ms were all associated with delayed progression to complete heart block and need for pacemaker implantation after TAVR.


Subject(s)
Heart Block/etiology , Heart Block/therapy , Pacemaker, Artificial , Postoperative Complications/etiology , Postoperative Complications/therapy , Transcatheter Aortic Valve Replacement , Aged, 80 and over , Disease Progression , Electrocardiography , Female , Heart Conduction System/physiopathology , Humans , Male , Retrospective Studies
18.
Aten Primaria ; 51(10): 617-625, 2019 12.
Article in Spanish | MEDLINE | ID: mdl-30857912

ABSTRACT

OBJECTIVES: To estimate insomnia prevalence as well as habits comorbidity, sleep quality of insomnia patients. DESIGN: Cross sectional descriptive study. SETTING: Calvia health center (Majorca, Spain). PARTICIPANTS: We included subjects registered in a Health Center (> 2 years) of 18-80 years old. METHODS: Firstly, they were interviewed by telephone in order to identify persons with insomnia using the Insomnia Severity Index. Afterward, subjects with insomnia were interviewed in the health center in order to collect the data. RESULTS: From a simple of 1,563 persons, we contacted 591 and 467 participated. Insomnia prevalence was 21.1% (IC 95% 17.38-25.01) and 6.9% (IC 95% 4.45-9.25) clinical insomnia. It was significantly more frequent in women, widow, divorced, retired and unemployed. Two in three presented obesity or overweight, 37% chronic pain, 21.1% depression and 37.9% anxiety. Half of the patients with insomnia referred a negative impact on daily activities and difficulties to maintain enthusiasm. Moreover, 41.1% declared to take pharmacological treatment for sleep usually. The more common therapeutic measures for insomnia were sleep hygiene and benzodiazepines; while cognitive-behavioral therapies were rarely used. CONCLUSIONS: The prevalence of insomnia in our health area is similar to those described in population based studies. The presence of some prejudicial habits for sleep quality as well as comorbidities could facilitate insomnia to become a chronic illness. Then, management of insomnia should be considered in a patient more general context. Pharmacological treatment is still in the first line and effective non pharmacological treatment is still a rare option.


Subject(s)
Sleep Initiation and Maintenance Disorders/epidemiology , Adult , Age Distribution , Aged , Aged, 80 and over , Confidence Intervals , Cross-Sectional Studies , Employment/statistics & numerical data , Female , Humans , Male , Marital Status/statistics & numerical data , Middle Aged , Prevalence , Severity of Illness Index , Sex Distribution , Sleep Initiation and Maintenance Disorders/therapy , Spain/epidemiology , Young Adult
19.
Actas Esp Psiquiatr ; 47(3): 88-96, 2019 May.
Article in English | MEDLINE | ID: mdl-31233207

ABSTRACT

OBJECTIVES: To compare alcohol and other drugs abuse, state impulsivity, craving and the relationship between craving and impulsivity in alcohol-dependent patients with or without dual disorder attending to an alcohol treatment center in Cadiz town. METHOD: An observational, descriptive and transversal study performed on 112 alcohol dependent patient sample who were seeking treatment in ARCA outpatient treatment center in Cadiz. The sample was divided in two groups, according to present dual diagnosis or not. The sample was assessed with an AdHoc sociodemographic and clinical questionnaire and specific scales and interviews that included: 5.0 Mini International Neuropsychiatric Interview results (MINI), State Impulsivity Scale (SIS), and Multidimensional Alcohol Craving Scale (MACS). RESULTS: The prevalence of dual diagnosis was 50%, being the most prevalent disorders: Current and recurrent Major Depressive Episode Mood Disorder, Current Dysthymic Mood Disorder, Panic Disorder and Anxiety Disorder. 52,7% of the total sample had a positive result on the State Impulsivity Scale. No statistically significant results were found on the Craving Scale (neither in the score or in the sub-sections). A relationship between craving and impulsivity were found for all groups and researched items. CONCLUSIONS: As a relationship between craving and impulsivity was observed, these aspects should be considered as main factors for the treatment and evolution of alcohol- dependent patients.


Subject(s)
Alcohol-Related Disorders/epidemiology , Craving/drug effects , Depressive Disorder, Major/epidemiology , Impulsive Behavior/drug effects , Outpatients/statistics & numerical data , Cross-Sectional Studies , Diagnosis, Dual (Psychiatry) , Female , Humans , Male , Middle Aged , Prevalence , Psychiatric Status Rating Scales , Spain/epidemiology
20.
Catheter Cardiovasc Interv ; 92(6): 1182-1193, 2018 11 15.
Article in English | MEDLINE | ID: mdl-29968273

ABSTRACT

BACKGROUND: We examined the outcomes of older adults undergoing nontrans-femoral (non-TF) transcatheter aortic valve replacement (TAVR) procedures including trans-apical (TA), trans-aortic (TAo), trans-subclavian (TSub), and trans-carotid (TCa) techniques. METHODS AND RESULTS: This is an observational study of all consecutive older patients who underwent non-TF TAVR for symptomatic severe AS with Edwards Sapien (ES), Medtronic CoreValve, ES3 or Lotus Valve at three centers in France and the United States from 04/2008 to 02/2017. Baseline characteristics and clinical outcomes were defined according to VARC-2 criteria. Of 857 patients who received TAVR, 172 (20%) had an alternative access procedure. Of these, 45 (26%) were TA, 67 (39%) TAo, 17 (10%) TSub, and 43 (25%) TCa procedures. The preference for non-TF access site was different between the two countries (US: TA 39%, TAo 52%, TSub 9%; TCa 0% vs. France: TA 9%, TAo 23%, TSub 11%, and TCa 57%, P-value < .001). Most patients who underwent TAo TAVR were older women (median age: TA 82, TAo 84, TSub 81, TCa 81, P-value = 0.043; female gender: TA 32 (27%), TAo 30 (55%), TSub 10 (41%), TCa 27 (37%), P-value = .021). The predicted Society of Thoracic Surgery risk of mortality was similar among groups (TA 7%, TAo 7%, TSub 6%, TCa 7%, P-value= .738). No differences were observed in the frequency of para-valvular leak, intra-procedural bleeding, vascular complications, conversion to open-heart surgery, or development of acute kidney injury. The highest in-hospital mortality was observed in the TAo group (TA 2%, TAo 15%, TSub 0%, TCa 2%, P-value = .014). However, hospital length of stay, one-month, and one-year mortality were similar among non-TF techniques. CONCLUSION: Although regional differences exist in the choice of alternative access techniques, centers with high technical expertise can provide a safe alternative to traditional TF TAVR. TAo TAVR was associated with higher in-hospital mortality than other non-TF approaches, and this may have reflected patient rather than procedural factors. All alternative access techniques had similar mortality rates and clinical outcomes at one-year follow-up. Trans-carotid access is safe and feasible compared to other non-TF access techniques.


Subject(s)
Aortic Valve Stenosis/surgery , Aortic Valve/surgery , Catheterization, Peripheral/methods , Transcatheter Aortic Valve Replacement , Aged , Aged, 80 and over , Aortic Valve/diagnostic imaging , Aortic Valve/physiopathology , Aortic Valve Stenosis/diagnostic imaging , Aortic Valve Stenosis/mortality , Aortic Valve Stenosis/physiopathology , Catheterization, Peripheral/adverse effects , Catheterization, Peripheral/mortality , Databases, Factual , Female , France , Hospital Mortality , Humans , Male , Postoperative Complications/mortality , Postoperative Complications/surgery , Reoperation , Risk Factors , Severity of Illness Index , Time Factors , Transcatheter Aortic Valve Replacement/adverse effects , Transcatheter Aortic Valve Replacement/instrumentation , Transcatheter Aortic Valve Replacement/mortality , Treatment Outcome , United States
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