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1.
J Bacteriol ; 204(3): e0053921, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35007156

RESUMO

DNA replication forks regularly encounter lesions or other impediments that result in a blockage to fork progression. PriA is one of the key proteins used by virtually all eubacteria to survive conditions that result in a blockage to replication fork movement. PriA directly binds stalled replication forks and initiates fork restart allowing for chromosomes to be fully duplicated under stressful conditions. We used a CRISPR-Cas gene editing approach to map PriA residues critical for surviving DNA damage induced by several antibiotics in B. subtilis. We find that the winged helix (WH) domain in B. subtilis PriA is critical for surviving DNA damage and participates in DNA binding. The important in vivo function of the WH domain mapped to distinct surfaces that were also conserved among several Gram-positive human pathogens. In addition, we identified an amino acid linker neighboring the WH domain that is greatly extended in B. subtilis due to an insertion. Shortening this linker induced a hypersensitive phenotype to DNA damage, suggesting that its extended length is critical for efficient replication fork restart in vivo. Because the WH domain is dispensable in E. coli PriA, our findings demonstrate an important difference in the contribution of the WH domain during fork restart in B. subtilis. Furthermore, with our results we suggest that this highly variable region in PriA could provide different functions across diverse bacterial organisms. IMPORTANCE PriA is an important protein found in virtually all bacteria that recognizes stalled replication forks orchestrating fork restart. PriA homologs contain a winged helix (WH) domain. The E. coli PriA WH domain is dispensable and functions in a fork restart pathway that is not conserved outside of E. coli and closely related proteobacteria. We analyzed the importance of the WH domain and an associated linker in B. subtilis and found that both are critical for surviving DNA damage. This function mapped to a small motif at the C-terminal end of the WH domain, which is also conserved in pathogenic bacteria. The motif was not required for DNA binding and therefore may perform a novel function in the replication fork restart pathway.


Assuntos
Bacillus subtilis , Proteínas de Escherichia coli , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , DNA/genética , Dano ao DNA , DNA Helicases/genética , Replicação do DNA , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo
2.
Liver Transpl ; 28(6): 936-944, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34596955

RESUMO

The Stanford Integrated Psychosocial Assessment for Transplant (SIPAT) is a validated interview tool to assess psychosocial well-being in candidates for solid organ transplants, with higher scores indicating greater vulnerability. We hypothesized that patients with alcohol-related liver disease (ALD) undergoing liver transplantation (LT) evaluation would have higher SIPAT scores than candidates with non-ALD, but that only patients with ALD who have low scores would be selected. We analyzed retrospectively consecutive adults undergoing LT evaluation from June 2018 to December 2019. Comparisons between patients with ALD and patients with non-ALD were made using the nonparametric Wilcoxon rank sum test plus a multivariate analysis to determine independent predictors for approval. In the study cohort of 358 patients, there were 199 (56%) patients with ALD with a mean age of 55 years, and 133 (67%) were men. There were 159 (44%) patients with non-ALD with a mean age of 57 years, and 95 (60%) were men. Mean Model for End-Stage Liver Disease-sodium scores were similar for selected versus not selected patients with ALD (25 versus 25.6) and selected versus not selected patients with non-ALD (18.3 versus 17.4), although the ALD group had substantially higher Model for End-Stage Liver Disease scores. Patients with ALD had higher mean SIPAT composite and individual domain scores compared with their non-ALD counterparts. SIPAT scores were not affected by age or sex. Proportionately more candidates with non-ALD were selected compared to candidates with ALD (68% versus 42%; P < 0.001; odds ratio for approval of non-ALD versus ALD, 2.9; 95% confidence interval, 1.8-4.7; P < 0.001). Composite SIPAT scores were lower in the selected versus nonselected in both ALD and non-ALD groups, although the SIPAT scores were significantly higher in selected patients with ALD (median, 39) than selected patients with non-ALD (median, 23; P = 0.001). Psychosocial assessment has a greater influence than acuity of liver failure on the selection of patients with ALD for LT listing, whereas psychosocial assessment has a minor influence on the selection of non-ALD candidates.


Assuntos
Doença Hepática Terminal , Hepatopatias Alcoólicas , Transplante de Fígado , Transplante de Órgãos , Adulto , Doença Hepática Terminal/diagnóstico , Doença Hepática Terminal/cirurgia , Feminino , Humanos , Hepatopatias Alcoólicas/complicações , Hepatopatias Alcoólicas/cirurgia , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Transplante de Órgãos/psicologia , Estudos Retrospectivos , Índice de Gravidade de Doença
3.
Nucleic Acids Res ; 48(10): 5332-5348, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32324221

RESUMO

The genomes of organisms from all three domains of life harbor endogenous base modifications in the form of DNA methylation. In bacterial genomes, methylation occurs on adenosine and cytidine residues to include N6-methyladenine (m6A), 5-methylcytosine (m5C), and N4-methylcytosine (m4C). Bacterial DNA methylation has been well characterized in the context of restriction-modification (RM) systems, where methylation regulates DNA incision by the cognate restriction endonuclease. Relative to RM systems less is known about how m6A contributes to the epigenetic regulation of cellular functions in Gram-positive bacteria. Here, we characterize site-specific m6A modifications in the non-palindromic sequence GACGmAG within the genomes of Bacillus subtilis strains. We demonstrate that the yeeA gene is a methyltransferase responsible for the presence of m6A modifications. We show that methylation from YeeA does not function to limit DNA uptake during natural transformation. Instead, we identify a subset of promoters that contain the methylation consensus sequence and show that loss of methylation within promoter regions causes a decrease in reporter expression. Further, we identify a transcriptional repressor that preferentially binds an unmethylated promoter used in the reporter assays. With these results we suggest that m6A modifications in B. subtilis function to promote gene expression.


Assuntos
Adenosina/análogos & derivados , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , DNA Metiltransferases Sítio Específica (Adenina-Específica)/metabolismo , Adenosina/análise , Adenosina/metabolismo , Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Cromossomos Bacterianos , Metilação de DNA , Enzimas de Restrição-Modificação do DNA , Epigênese Genética , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Regiões Promotoras Genéticas , Proteínas Repressoras/metabolismo , DNA Metiltransferases Sítio Específica (Adenina-Específica)/fisiologia , Fatores de Transcrição/metabolismo
4.
Int J Biometeorol ; 65(5): 749-762, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-31522261

RESUMO

The complexity of the human-environment interface predicates the need for tools and techniques that can enable the effective translation of weather and climate products into decision-relevant information. Indices are a category of such tools that may be used to simplify multi-faceted climate information for economic and other decision-making. Climate indices for tourism have been popularized in the literature over the past three decades, but despite their prevalence, these indices have a number of limitations, including coarse temporal resolution, subjective rating and weighting schemes, and lack of empirical validation. This paper critically assesses the design of the tourism climate index, the holiday climate index-beach, and a new, mathematically optimized index developed for the unique contextual realities of Great Lakes beach tourism. This new methodology combines the use of expert knowledge, stated visitor preferences, and mathematical optimization to develop an index that assigns daily weather scores based on four weather sub-indices (thermal comfort, wind speed, precipitation, and cloud cover). These daily scores are then averaged to the monthly level and correlated to visitation data at two beach parks in Ontario (Canada). This optimized index demonstrates a strong fit (R2 = 0.734, 0.657) with observed visitation at Pinery Provincial Park and Sandbanks Provincial Park, outperforming both the tourism climate index (R2 = 0.474, 0.018) and the holiday climate index-beach (R2 = 0.668, 0.427). This study advances our understanding of the magnitude and seasonality of weather impact on beach tourist visitation and can inform decision-making of tourism marketers and destination managers.


Assuntos
Turismo , Tempo (Meteorologia) , Clima , Humanos , Ontário , Vento
5.
J Bacteriol ; 202(21)2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817095

RESUMO

DnaB is an essential primosomal protein that coloads the replicative helicase in many Gram-positive bacteria, including several human pathogens. Although DnaB is tetrameric in solution, it is from a protein family whose members can oligomerize into large complexes when exposed to DNA. It is currently unknown how DNA binding by DnaB is regulated or how these interactions induce changes in its oligomeric state. Here, we investigated DNA binding by DnaB from Bacillus subtilis and the critical human pathogen Staphylococcus aureus We found that B. subtilis DnaB binds double-stranded DNA as a tetramer; however, M13mp18 single-stranded DNA induces high-order oligomerization. Mutating a conserved motif at the C-terminal end of DnaB stimulates single-stranded DNA binding, suggesting that conformational changes in this region regulate DNA substrate preferences. S. aureus DnaB could also be induced to form high-order oligomers with either M13mp18 or PhiX174 single-stranded DNA. Therefore, oligomeric shifts in DnaB are tightly controlled and this activity is conserved between B. subtilis and a pathogenic species.IMPORTANCE DnaB is a replicative helicase loader involved in initiating DNA replication in many bacterial species. We investigated the binding preferences of DnaB for its DNA substrate and determined that the C-terminal end of the protein plays a critical role in controlling DNA interactions. Furthermore, we found that DNA binding in general did not trigger changes to the oligomeric state of DnaB, but rather, certain types of single-stranded DNA substrates specifically induced DnaB to self-assemble into a large complex. This indicates that the structure of DNA itself is an important regulatory element that influences the behavior of DnaB. Importantly, these observations held for both Bacillus subtilis and the pathogenic species Staphylococcus aureus, demonstrating conserved biochemical functions of DnaB in these species.


Assuntos
Bacillus subtilis , Proteínas de Bactérias/metabolismo , DNA Bacteriano/metabolismo , Proteínas de Ligação a DNA/metabolismo , DnaB Helicases/metabolismo , Staphylococcus aureus , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Replicação do DNA , Conformação de Ácido Nucleico , Ligação Proteica , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
6.
Mol Microbiol ; 111(1): 118-130, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30285297

RESUMO

DNA replication is a fundamental biological process that is tightly regulated in all cells. In bacteria, DnaA controls when and where replication begins by building a step-wise complex that loads the replicative helicase onto chromosomal DNA. In many low-GC Gram-positive species, DnaA recruits the DnaD and DnaB proteins to function as adaptors to assist in helicase loading. How DnaA, its adaptors and the helicase form a complex at the origin is unclear. We addressed this question using the bacterial two-hybrid assay to determine how the initiation proteins from Bacillus subtilis interact with each other. We show that cryptic interaction sites play a key role in this process and we map these regions for the entire pathway. In addition, we found that the SirA regulator that blocks initiation in sporulating cells binds to a surface on DnaA that overlaps with DnaD. The interaction between DnaA and DnaD was also mapped to the same DnaA surface in the human pathogen Staphylococcus aureus, demonstrating the broad conservation of this surface. Therefore, our study has unveiled key protein interactions essential for initiation and our approach is widely applicable for mapping interactions in other signaling pathways that are governed by cryptic binding surfaces.


Assuntos
Bacillus subtilis/enzimologia , Proteínas de Bactérias/metabolismo , Replicação do DNA , Proteínas de Ligação a DNA/metabolismo , DnaB Helicases/metabolismo , Multimerização Proteica , Bacillus subtilis/genética , Sítios de Ligação , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Mapeamento de Interação de Proteínas , Staphylococcus aureus/enzimologia , Staphylococcus aureus/genética , Técnicas do Sistema de Duplo-Híbrido
7.
Arch Phys Med Rehabil ; 101(10): 1796-1812, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32416149

RESUMO

OBJECTIVE: This systematic review examines the facilitators and barriers to the use of patient-reported outcome measures (PROMs) in outpatient rehabilitation settings and provides strategies to improve care to maximize patient outcomes. DATA SOURCES: Eleven databases were systematically searched from November 2018 to May 2019. STUDY SELECTION: Two reviewers independently assessed articles based on the following inclusion criteria: English text, evaluate barriers and facilitators, include PROMs, and occur in an outpatient rehabilitation setting (physical therapy, occupational therapy, speech language pathology, or athletic training). Of the 10,164 articles initially screened, 15 articles were included in this study. DATA EXTRACTION: Data were extracted from the selected articles by 2 independent reviewers and put into an extraction template and into the Consolidated Framework for Implementation Research (CFIR) model. The Appraisal Tool for Cross-Sectional Studies (AXIS) was conducted on each study to assess study design, risk of bias, and reporting quality of the eligible studies. DATA SYNTHESIS: Ten studies were identified as high quality, according to the AXIS. Based on the CFIR model, the top barriers identified focused on clinician training and time in the implementation process, lack of recognized value and knowledge at the individual level, lack of access and support in the inner setting, and inability of patients to complete PROMs in the intervention process. Facilitators were identified as education in the implementation process, support and availability of PROMs in the inner setting, and recognized value at the individual level. CONCLUSIONS: More barriers than facilitators have been identified, which is consistent with PROM underuse. Clinicians and administrators should find opportunities to overcome the barriers identified and leverage the facilitators to improve routine PROM use and maximize patient outcomes.


Assuntos
Medidas de Resultados Relatados pelo Paciente , Centros de Reabilitação/organização & administração , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Avaliação de Resultados em Cuidados de Saúde/métodos , Pacientes Ambulatoriais , Centros de Reabilitação/normas , Fatores de Tempo
8.
Biophys J ; 116(4): 684-693, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30686488

RESUMO

The replisome is a multiprotein machine responsible for the faithful replication of chromosomal and plasmid DNA. Using single-molecule super-resolution imaging, we characterized the dynamics of three replisomal proteins in live Bacillus subtilis cells: the two replicative DNA polymerases, PolC and DnaE, and a processivity clamp loader subunit, DnaX. We quantified the protein mobility and dwell times during normal replication and following replication fork stress using damage-independent and damage-dependent conditions. With these results, we report the dynamic and cooperative process of DNA replication based on changes in the measured diffusion coefficients and dwell times. These experiments show that the replication proteins are all highly dynamic and that the exchange rate depends on whether DNA synthesis is active or arrested. Our results also suggest coupling between PolC and DnaX in the DNA replication process and indicate that DnaX provides an important role in synthesis during repair. Furthermore, our results suggest that DnaE provides a limited contribution to chromosomal replication and repair in vivo.


Assuntos
Proteínas de Bactérias/metabolismo , DNA Polimerase III/metabolismo , Replicação do DNA , DNA Polimerase Dirigida por DNA/metabolismo , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Dano ao DNA
9.
Crit Rev Biochem Mol Biol ; 50(3): 181-93, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25387798

RESUMO

In all living cells, DNA is the storage medium for genetic information. Being quite stable, DNA is well-suited for its role in storage and propagation of information, but RNA is also covalently included in DNA through various mechanisms. Recent studies also demonstrate useful aspects of including ribonucleotides in the genome during repair. Therefore, our understanding of the consequences of RNA inclusion into bacterial genomic DNA is just beginning, but with its high frequency of occurrence the consequences and potential benefits are likely to be numerous and diverse. In this review, we discuss the processes that cause ribonucleotide inclusion in genomic DNA, the pathways important for ribonucleotide removal and the consequences that arise should ribonucleotides remain nested in genomic DNA.


Assuntos
Reparo do DNA , Replicação do DNA , DNA Bacteriano/química , Escherichia coli/metabolismo , Ribonucleotídeos/metabolismo , Bacillus subtilis/metabolismo , DNA Polimerase I/metabolismo , DNA Bacteriano/metabolismo , Escherichia coli/enzimologia
10.
Liver Int ; 36(12): 1783-1792, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27232579

RESUMO

BACKGROUND: Chronic liver injury can result in fibrosis that may progress over years to end-stage liver disease. The most effective anti-fibrotic therapy is treatment of the underlying disease, however when not possible, interventions to reverse or slow fibrosis progression are needed. AIM: The aim of this study was to study the safety and tolerability of simtuzumab, a monoclonal antibody directed against lysyl oxidase-like 2 (LOXL2) enzyme, in subjects with hepatitis C virus (HCV), human immunodeficiency virus (HIV), or HCV-HIV co-infection and advanced liver disease. METHODS: Eighteen subjects with advanced liver fibrosis received simtuzumab 700 mg intravenously every 2 weeks for 22 weeks. Transjugular liver biopsies were performed during screening and at the end of treatment to measure hepatic venous pressure gradient (HVPG) and to stage fibrosis. RESULTS: Treatment was well-tolerated with no discontinuations due to adverse events. No significant changes were seen in HVPG or liver biopsy fibrosis score after treatment. Exploratory transcriptional and protein profiling using paired pre- and post-treatment liver biopsy and serum samples suggested up-regulation of TGF-ß3 and IL-10 pathways with treatment. CONCLUSION: In this open-label, pilot clinical trial, simtuzumab treatment was well-tolerated in HCV- and HIV-infected subjects with advanced liver disease. Putative modulation of TGF-ß3 and IL-10 pathways during simtuzumab treatment merits investigation in future trials.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Coinfecção/complicações , Infecções por HIV/complicações , Hepatite C Crônica/complicações , Cirrose Hepática/tratamento farmacológico , Administração Intravenosa , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Coinfecção/virologia , Progressão da Doença , Feminino , Humanos , Interleucina-10/sangue , Fígado/patologia , Cirrose Hepática/virologia , Masculino , Maryland , Pessoa de Meia-Idade , Pressão na Veia Porta/efeitos dos fármacos , Fator de Crescimento Transformador beta3/sangue , Resultado do Tratamento
11.
Anim Cogn ; 19(1): 207-14, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26433604

RESUMO

We assessed motor laterality in sheep to explore species-specific brain hemi-field dominance and how this could be affected by genetic or developmental factors. Further, we investigated whether directionality and strength of laterality could be linked to emotional stress in ewes and their lambs during partial separation. Forty-three ewes and their singleton lambs were scored on the (left/right) direction of turn in a y-maze to rejoin a conspecific (laterality test). Further, their behavioural response (i.e. time spent near the fence, vocalisations, and activity level) during forced separation by an open-mesh fence was assessed (separation test). Individual laterality was recorded for 44.2% ewes (significant right bias) and 81.4% lambs (equally biased to the left and the right). There was no significant association in side bias between dams and offspring. The Chi-squared test revealed a significant population bias for both groups (p < 0.05). Evolutionary adaptive strategies or stimuli-related visual laterality may provide explanation for this decision-making process. Absolute strength of laterality (irrespective of side) was high (Kolmogorov-Smirnov test, dams: D = 0.2; p < 0.001; lambs: D = 0.36, p < 0.0001). The Wilcoxon test showed that lateralised lambs and dams spent significantly more time near each other during separation than non-lateralised animals (p < 0.05), and that lateralised dams were also more active than non-lateralised ones. Arguably, the lateralised animals showed a greater attraction to their pair because they were more disturbed and thus required greater reassurance. The data show that measures of laterality offer a potential novel non-invasive indicator of separation stress.


Assuntos
Comportamento Animal/fisiologia , Lateralidade Funcional/fisiologia , Carneiro Doméstico/fisiologia , Estresse Psicológico , Animais , Tomada de Decisões/fisiologia , Feminino , Masculino , Carneiro Doméstico/psicologia , Vocalização Animal
12.
Psychosomatics ; 57(4): 423-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27095586

RESUMO

BACKGROUND: Post-traumatic stress disorder (PTSD) may be associated with chronic immune dysregulation and a proinflammatory state. Among HIV-infected individuals, PTSD is associated with greater morbidity and mortality, but the association with immune dysfunction has not been evaluated. This study explores the association between PTSD and selected markers of inflammation and immune activation in a cohort of HIV-infected, virally-suppressed individuals. METHODS: HIV-infected adults who were virologically controlled on antiretroviral medications were recruited through a screening protocol for studies of HIV-related neurocognitive disorders. Each participant underwent blood draws, urine toxicology screen, and completed the Client Diagnostic Questionnaire, a semistructured psychiatric interview. RESULTS: Of 114 eligible volunteers, 72 (63%) were male, 77 (68%) African American, and 34 (30%) participants met criteria for PTSD. Participants with PTSD were more likely to be current smokers (79%) than those without (60%) (p = 0.05). The PTSD cohort had significantly higher total white blood cell counts (5318 and 6404 cells/uL, p = 0.03), absolute neutrophil count (2767 and 3577 cells/uL, p = 0.02), CD8% (43 and 48, p = 0.05), and memory CD8% (70 and 78%, p = 0.04); lower naïve CD8% (30 and 22%, p = 0.04) and higher rate of high-sensitivity C-reactive protein >3mg/L (29 and 20, p = 0.03). DISCUSSION: A high prevalence of PTSD was identified in this cohort of HIV-infected adults who were virally suppressed. These results suggest that PTSD may be associated with immune dysregulation even among antiretroviral therapy-adherent HIV-infected individuals.


Assuntos
Proteína C-Reativa/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Transtornos de Estresse Pós-Traumáticos/imunologia , Adulto , Negro ou Afro-Americano , Terapia Antirretroviral de Alta Atividade , Biomarcadores , Linfócitos T CD8-Positivos/citologia , Estudos de Casos e Controles , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Humanos , Inflamação , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Neutrófilos/citologia , Neutrófilos/imunologia , Prevalência , Fumar/epidemiologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Inquéritos e Questionários , Carga Viral , População Branca
13.
J Biol Chem ; 289(5): 2589-99, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24285546

RESUMO

Forkhead-associated (FHA) and BRCA1 C-terminal (BRCT) domains are overrepresented in DNA damage and replication stress response proteins. They function primarily as phosphoepitope recognition modules but can also mediate non-canonical interactions. The latter are rare, and only a few have been studied at a molecular level. We have identified a crucial non-canonical interaction between the N-terminal FHA1 domain of the checkpoint effector kinase Rad53 and the BRCT domain of the regulatory subunit of the Dbf4-dependent kinase that is critical to suppress late origin firing and to stabilize stalled forks during replication stress. The Rad53-Dbf4 interaction is phosphorylation-independent and involves a novel non-canonical interface on the FHA1 domain. Mutations within this surface result in hypersensitivity to genotoxic stress. Importantly, this surface is not conserved in the FHA2 domain of Rad53, suggesting that the FHA domains of Rad53 gain specificity by engaging additional interaction interfaces beyond their phosphoepitope-binding site. In general, our results point to FHA domains functioning as complex logic gates rather than mere phosphoepitope-targeting modules.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Quinase do Ponto de Checagem 2/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Quinase do Ponto de Checagem 2/química , Quinase do Ponto de Checagem 2/genética , Biologia Computacional , Dano ao DNA/fisiologia , Replicação do DNA/fisiologia , Fatores de Transcrição Forkhead/química , Genes cdc/fisiologia , Ligação Proteica/fisiologia , Domínios e Motivos de Interação entre Proteínas/fisiologia , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética
14.
Clin Infect Dis ; 60(10): 1569-78, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25681381

RESUMO

BACKGROUND: Persistent aminotransferase elevations are common in human immunodeficiency virus (HIV)-infected patients on antiretroviral therapy (ART), including those without hepatitis B or C coinfection, but their clinical significance is unknown. METHODS: HIV-infected adults with aminotransferase levels elevated above the upper limit of normal for ≥6 months while receiving ART, and without chronic viral hepatitis or other known causes of chronic liver disease, underwent a detailed metabolic assessment and liver biopsy. RESULTS: Sixty-two HIV-infected subjects completed the study. Forty (65%) had clinically significant liver pathology, including 34 (55%) with nonalcoholic steatohepatitis (NASH) and 11 (18%) with bridging fibrosis, 10 of whom also had NASH. Nonspecific abnormalities alone were seen in 22 (35%) subjects, including mild steatosis, mild to moderate inflammation, and evidence of drug adaptation. Insulin resistance, obesity, and the presence of either of 2 minor alleles in the PNPLA3 gene were significantly associated with increased risk of NASH and fibrosis. NASH and/or fibrosis were not associated with duration of HIV infection or ART, specific antiretroviral drugs, history of opportunistic infection, immune status, or duration of aminotransferase elevation. CONCLUSIONS: HIV-infected adults with chronic aminotransferase elevations while receiving ART have a high rate of liver disease. Noninvasive testing can help identify liver disease in such patients, but liver biopsy is necessary to definitively identify those at risk for liver disease progression and complications. Longitudinal follow-up of this cohort will better characterize the natural history of aminotransferase elevations in this population and identify noninvasive biomarkers of liver disease progression.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Cirrose Hepática/epidemiologia , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Transaminases/sangue , Adolescente , Adulto , Idoso , Biópsia , Análise Química do Sangue , Estudos de Coortes , Feminino , Histocitoquímica , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
15.
J Bacteriol ; 196(19): 3363-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25049091

RESUMO

All living organisms must repair DNA double-stranded breaks (DSBs) in order to survive. Many bacteria rely on nonhomologous end joining (NHEJ) when only a single copy of the genome is available and maintain NHEJ pathways with a minimum of two proteins. In this issue, Bhattarai and colleagues identify additional factors that can work together to aid in survival of stationary-phase cells with chromosomal breaks.


Assuntos
Proteínas de Bactérias/metabolismo , Reparo do DNA por Junção de Extremidades , DNA Ligases/metabolismo , DNA Bacteriano/genética , DNA Polimerase Dirigida por DNA/metabolismo , Mycobacterium smegmatis/enzimologia , Mycobacterium smegmatis/genética , DNA Ligase Dependente de ATP
16.
J Biol Chem ; 287(4): 2378-87, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22130670

RESUMO

Dbf4 is a conserved eukaryotic protein that functions as the regulatory subunit of the Dbf4-dependent kinase (DDK) complex. DDK plays essential roles in DNA replication initiation and checkpoint activation. During the replication checkpoint, Saccharomyces cerevisiae Dbf4 is phosphorylated in a Rad53-dependent manner, and this, in turn, inhibits initiation of replication at late origins. We have determined the minimal region of Dbf4 required for the interaction with the checkpoint kinase Rad53 and solved its crystal structure. The core of this fragment of Dbf4 folds as a BRCT domain, but it includes an additional N-terminal helix unique to Dbf4. Mutation of the residues that anchor this helix to the domain core abolish the interaction between Dbf4 and Rad53, indicating that this helix is an integral element of the domain. The structure also reveals that previously characterized Dbf4 mutants with checkpoint phenotypes destabilize the domain, indicating that its structural integrity is essential for the interaction with Rad53. Collectively, these results allow us to propose a model for the association between Dbf4 and Rad53.


Assuntos
Proteínas de Ciclo Celular/química , Modelos Moleculares , Dobramento de Proteína , Proteínas Serina-Treonina Quinases/química , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Quinase do Ponto de Checagem 2 , Cristalografia por Raios X , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Estabilidade Proteica , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Relação Estrutura-Atividade
17.
Hepatol Commun ; 7(1): e0017, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36633478

RESUMO

BACKGROUND: Our research showed that patients with alcohol-associated liver disease (ALD) had more severe liver disease than those without a diagnosis of ALD yet were less likely to be selected for transplant listing due to their increased psychosocial vulnerability. This study aims to answer whether this vulnerability translates to worse short-term outcomes after transplant listing. METHODS: A total of 187 patients were approved for liver transplant listing and are included in the present retrospective study. We collected dates of transplantation, retransplantation, death, and pathologic data for evidence of rejection, and reviewed alcohol biomarkers and documentation for evidence of alcohol use. RESULTS: The ALD cohort had higher Stanford Integrated Psychosocial Assessment for Transplant (SIPAT) scores (39.4 vs. 22.5, p <0.001) and Model for End-Stage Liver Disease (MELD)-Na scores (25.0 vs. 18.5, p <0.001) compared with the non-ALD cohort. Forty-nine (59.7%) subjects with ALD and 60 (57.1%, p =0.71) subjects without ALD subsequently received a liver transplant. Overall mortality was similar between the 2 groups (20.7% ALD vs. 21.0% non-ALD, p =0.97). Neither the SIPAT score (HR: 0.98, 95% CI: 0.96-1.00, p =0.11) nor MELD-Na score (HR 0.99, 95% CI 0.95-1.02, p =0.40) were associated with mortality. Patients with ALD were more likely to have alcohol biomarkers tested both before (84.1% vs. 24.8% non-ALD, p <0.001) and after liver transplantation (74.0% vs. 16.7% non-ALD, p <0.001). SIPAT score was associated with alcohol use after listing (OR: 1.03, 95% CI: 1.0-1.07, p =0.04), although a return to alcohol use was not associated with mortality (HR: 1.60, 95% CI: 0.63-4.10, p =0.33). CONCLUSION: Patients with ALD had higher psychosocial risk compared with patients without a diagnosis of ALD who were placed on the waitlist, but had similar short-term outcomes including mortality, transplantation, and rejection. Although a high SIPAT score was predictive of alcohol use, in the short-term, alcohol use after transplant listing was not associated with mortality.


Assuntos
Doença Hepática Terminal , Hepatopatias Alcoólicas , Transplante de Fígado , Humanos , Doença Hepática Terminal/diagnóstico , Doença Hepática Terminal/cirurgia , Estudos Retrospectivos , Índice de Gravidade de Doença , Biomarcadores
18.
JMIR Rehabil Assist Technol ; 10: e43250, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37224276

RESUMO

BACKGROUND: Patients who were incarcerated were disproportionately affected by COVID-19 compared with the general public. Furthermore, the impact of multidisciplinary rehabilitation assessments and interventions on the outcomes of patients admitted to the hospital with COVID-19 is limited. OBJECTIVE: We aimed to compare the functional outcomes of oral intake, mobility, and activity between inmates and noninmates diagnosed with COVID-19 and examine the relationships among these functional measures and discharge destination. METHODS: A retrospective analysis was performed on patients admitted to the hospital for COVID-19 at a large academic medical center. Scores on functional measures including the Functional Oral Intake Scale and Activity Measure for Postacute Care (AM-PAC) were collected and compared between inmates and noninmates. Binary logistic regression models were used to evaluate the odds of whether patients were discharged to the same place they were admitted from and whether patients were being discharged with a total oral diet with no restrictions. Independent variables were considered significant if the 95% CIs of the odds ratios (ORs) did not include 1.0. RESULTS: A total of 83 patients (inmates: n=38; noninmates: n=45) were included in the final analysis. There were no differences between inmates and noninmates in the initial (P=.39) and final Functional Oral Intake Scale scores (P=.35) or in the initial (P=.06 and P=.46), final (P=.43 and P=.79), or change scores (P=.97 and P=.45) on the AM-PAC mobility and activity subscales, respectively. When examining separate regression models using AM-PAC mobility or AM-PAC activity scores as independent variables, greater age upon admission decreased the odds (OR 0.922, 95% CI 0.875-0.972 and OR 0.918, 95% CI 0.871-0.968) of patients being discharged with a total oral diet with no restrictions. The following factors increased the odds of patients being discharged to the same place they were admitted from: being an inmate (OR 5.285, 95% CI 1.334-20.931 and OR 6.083, 95% CI 1.548-23.912), "Other" race (OR 7.596, 95% CI 1.203-47.968 and OR 8.515, 95% CI 1.311-55.291), and female sex (OR 4.671, 95% CI 1.086-20.092 and OR 4.977, 95% CI 1.146-21.615). CONCLUSIONS: The results of this study provide an opportunity to learn how functional measures may be used to better understand discharge outcomes in both inmate and noninmate patients admitted to the hospital with COVID-19 during the initial period of the pandemic.

19.
Clin Liver Dis (Hoboken) ; 19(1): 17-20, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35106144

RESUMO

Content available: Author Interview and Audio Recording.

20.
Physiother Theory Pract ; : 1-9, 2022 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-36567617

RESUMO

INTRODUCTION: Low back pain (LBP) is the top health condition requiring rehabilitation in the United States. The financial burden of managing LBP is also amongst the highest in the United States. Clinical practice guidelines (CPGs) provide management recommendations and have the potential to lower health costs. Limited evidence exists on the impact of CPG implementation on downstream medical costs. OBJECTIVE: To examine the impact of CPG implementation in physical therapist (PT) practice on direct and downstream costs for patients with LBP. METHODS: A retrospective observational study examined billing data from 270 patients with LBP who were treated at multiple sites within one large academic medical center by PTs who participated in a multifaceted CPG implementation program. Costs were analyzed for direct PT services, downstream medical services, and PT utilization from September 2017 to March 2018 (pre-implementation group) and compared with costs from June 2018 to December 2018 (post-implementation group). RESULTS: Direct PT costs were significantly lower post-implementation than pre-implementation mean: $2,863 USD (SD: $1,968) vs. $3,459 USD (SD: $2,838), p = .05, 95% CI [11, 1182]. All downstream costs were lower post-implementation with statistically significant lower costs found in downstream imaging: p = .04, 95% CI [32, 1,905]; pharmacy: p = .03, 95% CI [70, 1,217]; surgery: p = .03, 95% CI [446, 9,152], and "other": p = .02, 95% CI [627, 7,920]. CONCLUSION: Implementing the LBP CPG in outpatient PT practice can have a positive impact on lowering downstream costs and the potential to increase the value of PT services.

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