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1.
J Exp Biol ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38757152

RESUMO

Myxine limosa is a burrowing species of hagfish that occurs in the western north Atlantic in areas with muddy substrate and at depths generally greater than 100 meters. Burrowing of M. limosa has been observed from submersibles, but little is known about the behavior of these animals within the substrate or the biomechanical mechanisms involved. Here we investigated burrowing in M. limosa by observing individuals as they burrowed through transparent gelatin. A photoelastic setup using crossed polarizers allowed us to visualize stress development in the gelatin as the hagfish moved through it. We found that M. limosa created U-shaped burrows in gelatin using a stereotyped, two-phase burrowing behavior. In the first ("Thrash") phase, hagfish drove their head and their anterior body into the substrate using vigorous sinusoidal swimming movements, with their head moving side-to-side. In the second ("Wriggle") phase, swimming movements ceased, with propulsion coming exclusively from the anterior, submerged portion of body. The Wriggle phase involved side-to-side head movements and movements of the submerged part of the body that resembled the "internal concertina" strategy used by caecilians and uropeltid snakes. The entire burrowing process took on average 7.6 minutes to complete and ended with the hagfish's head protruding from the substrate and the rest of its body generally concealed. Understanding the burrowing activities of hagfishes could lead to improved understanding of sediment turnover in marine benthic habitats, new insights into the reproductive behavior of hagfishes, or even inspiration for the design of burrowing robots.

2.
Mol Ther ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702886

RESUMO

In the rapidly evolving landscape of medical research, the emergence of RNA-based therapeutics is paradigm shifting. It is mainly driven by the molecular adaptability and capacity to provide precision in targeting. The coronavirus disease 2019 pandemic crisis underscored the effectiveness of the mRNA therapeutic development platform and brought it to the forefront of RNA-based interventions. These RNA-based therapeutic approaches can reshape gene expression, manipulate cellular functions, and correct the aberrant molecular processes underlying various diseases. The new technologies hold the potential to engineer and deliver tailored therapeutic agents to tackle genetic disorders, cancers, and infectious diseases in a highly personalized and precisely tuned manner. The review discusses the most recent advancements in the field of mRNA therapeutics for cancer treatment, with a focus on the features of the most utilized RNA-based therapeutic interventions, current pre-clinical and clinical developments, and the remaining challenges in delivery strategies, effectiveness, and safety considerations.

3.
Nat Commun ; 15(1): 2340, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491013

RESUMO

Protein synthesis is frequently deregulated during tumorigenesis. However, the precise contexts of selective translational control and the regulators of such mechanisms in cancer is poorly understood. Here, we uncovered CNOT3, a subunit of the CCR4-NOT complex, as an essential modulator of translation in myeloid leukemia. Elevated CNOT3 expression correlates with unfavorable outcomes in patients with acute myeloid leukemia (AML). CNOT3 depletion induces differentiation and apoptosis and delayed leukemogenesis. Transcriptomic and proteomic profiling uncovers c-MYC as a critical downstream target which is translationally regulated by CNOT3. Global analysis of mRNA features demonstrates that CNOT3 selectively influences expression of target genes in a codon usage dependent manner. Furthermore, CNOT3 associates with the protein network largely consisting of ribosomal proteins and translation elongation factors in leukemia cells. Overall, our work elicits the direct requirement for translation efficiency in tumorigenesis and propose targeting the post-transcriptional circuitry via CNOT3 as a therapeutic vulnerability in AML.


Assuntos
Leucemia Mieloide Aguda , Proteômica , Fatores de Transcrição , Humanos , Carcinogênese/genética , Diferenciação Celular , Leucemia Mieloide Aguda/genética , Receptores CCR4 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Cell Rep Med ; 4(7): 101110, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37467717

RESUMO

Multiple myeloma (MM) is an incurable malignancy of plasma cells. To identify targets for MM immunotherapy, we develop an integrated pipeline based on mass spectrometry analysis of seven MM cell lines and RNA sequencing (RNA-seq) from 900+ patients. Starting from 4,000+ candidates, we identify the most highly expressed cell surface proteins. We annotate candidate protein expression in many healthy tissues and validate the expression of promising targets in 30+ patient samples with relapsed/refractory MM, as well as in primary healthy hematopoietic stem cells and T cells by flow cytometry. Six candidates (ILT3, SEMA4A, CCR1, LRRC8D, FCRL3, IL12RB1) and B cell maturation antigen (BCMA) present the most favorable profile in malignant and healthy cells. We develop a bispecific T cell engager targeting ILT3 that shows potent killing effects in vitro and decreased tumor burden and prolonged mice survival in vivo, suggesting therapeutic relevance. Our study uncovers MM-associated antigens that hold great promise for immune-based therapies of MM.


Assuntos
Mieloma Múltiplo , Animais , Camundongos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Imunoterapia/métodos , Linfócitos T , Plasmócitos/metabolismo
5.
Nat Commun ; 14(1): 2290, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-37085479

RESUMO

Tissue homeostasis is maintained after stress by engaging and activating the hematopoietic stem and progenitor compartments in the blood. Hematopoietic stem cells (HSCs) are essential for long-term repopulation after secondary transplantation. Here, using a conditional knockout mouse model, we revealed that the RNA-binding protein SYNCRIP is required for maintenance of blood homeostasis especially after regenerative stress due to defects in HSCs and progenitors. Mechanistically, we find that SYNCRIP loss results in a failure to maintain proteome homeostasis that is essential for HSC maintenance. SYNCRIP depletion results in increased protein synthesis, a dysregulated epichaperome, an accumulation of misfolded proteins and induces endoplasmic reticulum stress. Additionally, we find that SYNCRIP is required for translation of CDC42 RHO-GTPase, and loss of SYNCRIP results in defects in polarity, asymmetric segregation, and dilution of unfolded proteins. Forced expression of CDC42 recovers polarity and in vitro replating activities of HSCs. Taken together, we uncovered a post-transcriptional regulatory program that safeguards HSC self-renewal capacity and blood homeostasis.


Assuntos
Células-Tronco Hematopoéticas , Ribonucleoproteínas Nucleares Heterogêneas , Proteostase , Animais , Camundongos , Regulação da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Camundongos Knockout , Proteostase/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
6.
Int J Hematol ; 117(6): 807-820, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36929506

RESUMO

RNA modifications play an important role in various cancers including blood cancers by controlling gene expression programs critical for survival, proliferation and differentiation of cancer cells. While hundreds of RNA modifications have been identified, many have not been functionally characterized. With development of enabling technologies to identify and map RNA modifications, tremendous advancement has been made in our understanding of the biological functions of these molecular markers in diverse cellular contexts. In the last 5 years, N6-methyladenosine (m6A), the most prevalent internal mRNA modification, has been extensively implicated in many facets of leukemogenesis. Other types of RNA modifications are also involved in the regulation of cell fate decisions and tumorigenesis. Here, we summarize existing knowledge and recent discoveries regarding the role of RNA modifications in leukemia. We choose to highlight cutting-edge techniques to characterize and profile RNA modifications while discussing critical functions of key modifiers and regulatory mechanisms in the pathogenesis of hematological malignancies and touch on therapeutic strategies targeting RNA modifications. These important advancements in the field will continue to foster a strong foundation for the development of innovative treatments for hematological malignancies.


Assuntos
Neoplasias Hematológicas , Leucemia , Humanos , RNA Mensageiro/genética , Diferenciação Celular , Leucemia/genética , Leucemia/terapia , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/terapia
7.
Biochem Cell Biol ; 101(2): 131-147, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36645883

RESUMO

RNA deadenylation, the process of shortening of the 3' poly(A) tail of an RNA molecule, is one of the key steps of post-transcriptional regulation of gene expression in eukaryotic cells. PAN2/3 and CCR4-NOT (CNOT) are the two dominant RNA deadenylation complexes, which play central roles in mediating mRNA decay and translation. While degradation is the final fate of virtually all RNAs in their life cycles, selection of RNA targets as well as control of the rate and timing of RNA decay, in coordination with other molecular pathways, including translation, can be modulated in certain contexts. Such regulation influences cell growth, proliferation, and differentiation at the cellular level; and contributes to establish polarity and regulate signaling at the tissue level. Dysregulation of deadenylation processes have also been implicated in human diseases ranging from cardiac diseases and neurodevelopmental disorders to cancers. In this review, we will discuss mechanisms of gene expression control mediated by the RNA deadenylation complexes and highlight relevant evidence supporting the emerging roles of RNA deadenylation and its regulatory proteins during development and in diseases. A systemic understanding of these mechanisms will be a critical foundation for development of effective strategies to therapeutically target them.


Assuntos
Exorribonucleases , RNA , Humanos , RNA/genética , Exorribonucleases/genética , Exorribonucleases/metabolismo , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica
8.
Blood Adv ; 7(15): 3846-3861, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-36322827

RESUMO

Regulation of gene expression at the RNA level is an important regulatory mechanism in cancer. However, posttranscriptional molecular pathways underlying tumorigenesis remain largely unexplored. In this study, we uncovered a functional axis consisting of microRNA (miR)-148a-3p, RNA helicase DDX6, and its downstream target thioredoxin-interacting protein (TXNIP) in acute myeloid leukemia (AML). Using a DROSHA-knockout cell system to evaluate miR-mediated gene expression control, we comprehensively profiled putative transcripts regulated by miR-148a-3p and identified DDX6 as a direct target of miR-148a-3p in AML cells. DDX6 depletion induced cell cycle arrest, apoptosis, and differentiation, although delaying leukemia development in vivo. Genome-wide assessment of DDX6-binding transcripts and gene expression profiling of DDX6-depleted cells revealed TXNIP, a tumor suppressor, as the functional downstream target of DDX6. Overall, our study identified DDX6 as a posttranscriptional regulator that is required for AML survival. We proposed the regulatory link between miR-148a-3p and DDX6 as a potential therapeutic target in leukemia.


Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Genes Supressores de Tumor , Leucemia Mieloide Aguda/genética , Diferenciação Celular/fisiologia , Proteínas Proto-Oncogênicas/genética , RNA Helicases DEAD-box/genética
9.
Exp Hematol ; 111: 25-31, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35487293

RESUMO

Post-transcriptional RNA modifications determine RNA fate by influencing numerous processes such as translation, decay and localization. One of the most abundant RNA modifications is N6-methyladenoside (m6A), which has been shown to be important in healthy as well as malignant hematopoiesis. Several proteins representing key players in m6A RNA biology, such as m6A writers, erasers and readers, were recently reported to be essential for hematopoietic stem cell (HSC) function. In leukemia, expression of m6A regulators has been shown to be increased, opening up potential opportunities for therapeutic exploitation by targeting them in blood malignancies. These recent discoveries were the focus of the Fall 2021 International Society for Experimental Hematology New Investigators webinar. We review here the latest findings in the field of mRNA modifications in normal and malignant hematopoiesis and how this might open up novel therapeutic options.


Assuntos
Hematopoese , Leucemia , Hematopoese/genética , Células-Tronco Hematopoéticas/metabolismo , Humanos , Leucemia/genética , RNA/metabolismo , Processamento Pós-Transcricional do RNA
10.
Nat Cancer ; 2: 741-757, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34458856

RESUMO

RNA binding proteins (RBPs) are key arbiters of post-transcriptional regulation and are found to be found dysregulated in hematological malignancies. Here, we identify the RBP RBMX and its retrogene RBMXL1 to be required for murine and human myeloid leukemogenesis. RBMX/L1 are overexpressed in acute myeloid leukemia (AML) primary patients compared to healthy individuals, and RBMX/L1 loss delayed leukemia development. RBMX/L1 loss lead to significant changes in chromatin accessibility, as well as chromosomal breaks and gaps. We found that RBMX/L1 directly bind to mRNAs, affect transcription of multiple loci, including CBX5 (HP1α), and control the nascent transcription of the CBX5 locus. Forced CBX5 expression rescued the RBMX/L1 depletion effects on cell growth and apoptosis. Overall, we determine that RBMX/L1 control leukemia cell survival by regulating chromatin state through their downstream target CBX5. These findings identify a mechanism for RBPs directly promoting transcription and suggest RBMX/L1, as well as CBX5, as potential therapeutic targets in myeloid malignancies.


Assuntos
Cromatina , Leucemia Mieloide Aguda , Animais , Cromatina/genética , Regulação da Expressão Gênica , Ribonucleoproteínas Nucleares Heterogêneas/genética , Humanos , Leucemia Mieloide Aguda/genética , Camundongos , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/genética
11.
HIV Med ; 22(3): 201-211, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33151020

RESUMO

OBJECTIVES: To assess second-line antiretroviral therapy (ART) virological failure and HIV drug resistance-associated mutations (RAMs), in support of third-line regimen planning in Asia. METHODS: Adults > 18 years of age on second-line ART for ≥ 6 months were eligible. Cross-sectional data on HIV viral load (VL) and genotypic resistance testing were collected or testing was conducted between July 2015 and May 2017 at 12 Asia-Pacific sites. Virological failure (VF) was defined as VL > 1000 copies/mL with a second VL > 1000 copies/mL within 3-6 months. FASTA files were submitted to Stanford University HIV Drug Resistance Database and RAMs were compared against the IAS-USA 2019 mutations list. VF risk factors were analysed using logistic regression. RESULTS: Of 1378 patients, 74% were male and 70% acquired HIV through heterosexual exposure. At second-line switch, median [interquartile range (IQR)] age was 37 (32-42) years and median (IQR) CD4 count was 103 (43.5-229.5) cells/µL; 93% received regimens with boosted protease inhibitors (PIs). Median duration on second line was 3 years. Among 101 patients (7%) with VF, CD4 count > 200 cells/µL at switch [odds ratio (OR) = 0.36, 95% confidence interval (CI): 0.17-0.77 vs. CD4 ≤ 50) and HIV exposure through male-male sex (OR = 0.32, 95% CI: 0.17-0.64 vs. heterosexual) or injecting drug use (OR = 0.24, 95% CI: 0.12-0.49) were associated with reduced VF. Of 41 (41%) patients with resistance data, 80% had at least one RAM to nonnucleoside reverse transcriptase inhibitors (NNRTIs), 63% to NRTIs, and 35% to PIs. Of those with PI RAMs, 71% had two or more. CONCLUSIONS: There were low proportions with VF and significant RAMs in our cohort, reflecting the durability of current second-line regimens.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Fármacos Anti-HIV/efeitos adversos , Estudos Transversais , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Mutação , Falha de Tratamento , Carga Viral
12.
Cell Stem Cell ; 27(6): 853-855, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33275897

RESUMO

COVID-19 has unfortunately halted lab work, conferences, and in-person networking, which is especially detrimental to researchers just starting their labs. Through social media and our reviewer networks, we met some early-career stem cell investigators impacted by the closures. Here, they introduce themselves and their research to our readers.


Assuntos
COVID-19 , Pesquisadores , Feminino , Humanos , Masculino
13.
Antivir Ther ; 25(3): 131-142, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32369040

RESUMO

BACKGROUND: This study investigated survival in people living with HIV being followed-up from 5 and 10 years after antiretroviral therapy (ART) initiation in a multi-country Asian cohort. METHODS: We included patients in follow-up >5 years after ART initiation. Factors associated with mortality beyond 5 and 10 years on ART were analysed using competing risk regression with time-updated variables. RESULTS: Of 13,495 patients retained after 5 years on ART, 279 subsequently died (0.56/100 person-years). Increased mortality was associated with age >50 years (sub-hazard ratio [sHR] 2.24, 95% CI 1.58, 3.15, compared with ≤40 years), HIV exposure through injecting drug use (sHR 2.17, 95% CI 1.32, 3.56), HIV viral load ≥1,000 copies/ml: sHR 1.52, 95% CI 1.05, 2.21, compared with <400), regimen (second-line regimen: sHR 2.11, 95% CI 1.52, 2.94, and third-line regimen: sHR 2.82, 95% CI 2.00, 3.98, compared with first-line regimen), HBV coinfection (sHR 2.23, 95% CI 1.49, 3.33), fasting plasma glucose ≥126 mg/dl (sHR 1.98, 95% CI 1.22, 3.21, compared with <100 mg/dl) and estimated glomerular filtration rate <60 ml/min/1.73 m2 (sHR 2.57, 95% CI 1.56, 4.22). Decreased mortality was associated with transmission through male-to-male sexual contact (sHR 0.44, 95% CI 0.22, 0.88, compared with heterosexual transmission) and higher CD4+ T-cell count (200-349 cells/µl: sHR 0.27, 95% CI 0.20, 0.38, 350-499 cells/µl: sHR 0.10, 95% CI 0.07, 0.16 and ≥500 cells/µl: sHR 0.09, 95% CI 0.06, 0.13, compared with <200 cells/µl). Results after 10 years were similar, but most associations were weaker due to limited power. CONCLUSIONS: Next to preventing ART failure, HIV programmes should carefully monitor and treat comorbidities, including hepatitis, kidney disease and diabetes, to optimize survival after long-term ART exposure.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Adulto , Fatores Etários , Feminino , Infecções por HIV/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Tailândia/epidemiologia , Fatores de Tempo , Carga Viral
14.
Nat Commun ; 11(1): 2026, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32332729

RESUMO

The cell-context dependency for RNA binding proteins (RBPs) mediated control of stem cell fate remains to be defined. Here we adapt the HyperTRIBE method using an RBP fused to a Drosophila RNA editing enzyme (ADAR) to globally map the mRNA targets of the RBP MSI2 in mammalian adult normal and malignant stem cells. We reveal a unique MUSASHI-2 (MSI2) mRNA binding network in hematopoietic stem cells that changes during transition to multipotent progenitors. Additionally, we discover a significant increase in RNA binding activity of MSI2 in leukemic stem cells compared with normal hematopoietic stem and progenitor cells, resulting in selective regulation of MSI2's oncogenic targets. This provides a basis for MSI2 increased dependency in leukemia cells compared to normal cells. Moreover, our study provides a way to measure RBP function in rare cells and suggests that RBPs can achieve differential binding activity during cell state transition independent of gene expression.


Assuntos
Diferenciação Celular/genética , Células-Tronco Hematopoéticas/patologia , Leucemia/genética , Células-Tronco Neoplásicas/patologia , Proteínas de Ligação a RNA/metabolismo , Adenosina Desaminase/genética , Animais , Sítios de Ligação/genética , Modelos Animais de Doenças , Proteínas de Drosophila/genética , Regulação Leucêmica da Expressão Gênica , Redes Reguladoras de Genes , Células HEK293 , Humanos , Leucemia/sangue , Leucemia/patologia , Camundongos , Camundongos Knockout , Cultura Primária de Células , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , RNA-Seq , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
15.
J Virus Erad ; 6(1): 11-18, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32175086

RESUMO

OBJECTIVES: Integration of HIV and non-communicable disease services improves the quality and efficiency of care in low- and middle-income countries (LMICs). We aimed to describe current practices for the screening and management of atherosclerotic cardiovascular disease (ASCVD) among adult HIV clinics in Asia. METHODS: Sixteen LMIC sites included in the International Epidemiology Databases to Evaluate AIDS - Asia-Pacific network were surveyed. RESULTS: Sites were mostly (81%) based in urban public referral hospitals. Half had protocols to assess tobacco and alcohol use. Protocols for assessing physical inactivity and obesity were in place at 31% and 38% of sites, respectively. Most sites provided educational material on ASCVD risk factors (between 56% and 75% depending on risk factors). A total of 94% reported performing routine screening for hypertension, 100% for hyperlipidaemia and 88% for diabetes. Routine ASCVD risk assessment was reported by 94% of sites. Protocols for the management of hypertension, hyperlipidaemia, diabetes, high ASCVD risk and chronic ischaemic stroke were in place at 50%, 69%, 56%, 19% and 38% of sites, respectively. Blood pressure monitoring was free for patients at 69% of sites; however, most required patients to pay some or all the costs for other ASCVD-related procedures. Medications available in the clinic or within the same facility included angiotensin-converting enzyme inhibitors (81%), statins (94%) and sulphonylureas (94%). CONCLUSION: The consistent availability of clinical screening, diagnostic testing and procedures and the availability of ASCVD medications in the Asian LMIC clinics surveyed are strengths that should be leveraged to improve the implementation of cardiovascular care protocols.

16.
HIV Med ; 21(6): 397-402, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31852025

RESUMO

OBJECTIVES: Early mortality among those still initiating antiretroviral therapy (ART) with advanced stages of HIV infection in resource-limited settings remains high despite recommendations for universal HIV treatment. We investigated risk factors associated with early mortality in people living with HIV (PLHIV) starting ART at low CD4 levels in the Asia-Pacific. METHODS: PLHIV enrolled in the Therapeutics, Research, Education and AIDS Training in Asia (TREAT Asia) HIV Observational Database (TAHOD) who initiated ART with a CD4 count < 100 cells/µL between 2003 and 2018 were included in the study. Early mortality was defined as death within 1 year of ART initiation. PLHIV in follow-up for > 1 year were censored at 12 months. Competing risk regression was used to analyse risk factors with loss to follow-up as a competing risk. RESULTS: A total of 1813 PLHIV were included in the study, of whom 74% were male. With 73 (4%) deaths, the overall first-year mortality rate was 4.27 per 100 person-years (PY). Thirty-eight deaths (52%) were AIDS-related, 10 (14%) were immune reconstituted inflammatory syndrome (IRIS)-related, 13 (18%) were non-AIDS-related and 12 (16%) had an unknown cause. Risk factors included having a body mass index (BMI) < 18.5 [sub-hazard ratio (SHR) 2.91; 95% confidence interval (CI) 1.60-5.32] compared to BMI 18.5-24.9, and alanine aminotransferase (ALT) ≥ 5 times its upper limit of normal (ULN) (SHR 6.14; 95% CI 1.62-23.20) compared to ALT < 5 times its ULN. A higher CD4 count (51-100 cells/µL: SHR 0.28; 95% CI 0.14-0.55; and > 100 cells/µL: SHR 0.12; 95% CI 0.05-0.26) was associated with reduced hazard for mortality compared to CD4 count ≤ 25 cells/µL. CONCLUSIONS: Fifty-two per cent of early deaths were AIDS-related. Efforts to initiate ART at CD4 counts > 50 cell/µL are associated with improved short-term survival rates, even in those with late stages of HIV disease.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/mortalidade , Adulto , Alanina Transaminase/metabolismo , Contagem de Linfócito CD4 , Causas de Morte , Feminino , Infecções por HIV/sangue , Infecções por HIV/metabolismo , Humanos , Masculino , Mortalidade , Pobreza , Tempo para o Tratamento
17.
Cell Rep ; 28(7): 1703-1716.e6, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31412241

RESUMO

Stem cells balance cellular fates through asymmetric and symmetric divisions in order to self-renew or to generate downstream progenitors. Symmetric commitment divisions in stem cells are required for rapid regeneration during tissue damage and stress. The control of symmetric commitment remains poorly defined. Using single-cell RNA sequencing (scRNA-seq) in combination with transcriptomic profiling of HSPCs (hematopoietic stem and progenitor cells) from control and m6A methyltransferase Mettl3 conditional knockout mice, we found that m6A-deficient hematopoietic stem cells (HSCs) fail to symmetrically differentiate. Dividing HSCs are expanded and are blocked in an intermediate state that molecularly and functionally resembles multipotent progenitors. Mechanistically, RNA methylation controls Myc mRNA abundance in differentiating HSCs. We identified MYC as a marker for HSC asymmetric and symmetric commitment. Overall, our results indicate that RNA methylation controls symmetric commitment and cell identity of HSCs and may provide a general mechanism for how stem cells regulate differentiation fate choice.


Assuntos
Diferenciação Celular , Linhagem da Célula , Hematopoese , Células-Tronco Hematopoéticas/citologia , Metiltransferases/fisiologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Feminino , Células-Tronco Hematopoéticas/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Metilação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Proto-Oncogênicas c-myc/genética , Estabilidade de RNA , Análise de Célula Única
18.
HIV Med ; 20(7): 439-449, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30980495

RESUMO

OBJECTIVES: With earlier antiretroviral therapy (ART) initiation, time spent in HIV care is expected to increase. We aimed to investigate loss to follow-up (LTFU) in Asian patients who remained in care 5 years after ART initiation. METHODS: Long-term LTFU was defined as LTFU occurring after 5 years on ART. LTFU was defined as (1) patients not seen in the previous 12 months; and (2) patients not seen in the previous 6 months. Factors associated with LTFU were analysed using competing risk regression. RESULTS: Under the 12-month definition, the LTFU rate was 2.0 per 100 person-years (PY) [95% confidence interval (CI) 1.8-2.2 among 4889 patients included in the study. LTFU was associated with age > 50 years [sub-hazard ratio (SHR) 1.64; 95% CI 1.17-2.31] compared with 31-40 years, viral load ≥ 1000 copies/mL (SHR 1.86; 95% CI 1.16-2.97) compared with viral load < 1000 copies/mL, and hepatitis C coinfection (SHR 1.48; 95% CI 1.06-2.05). LTFU was less likely to occur in females, in individuals with higher CD4 counts, in those with self-reported adherence ≥ 95%, and in those living in high-income countries. The 6-month LTFU definition produced an incidence rate of 3.2 per 100 PY (95% CI 2.9-3.4 and had similar associations but with greater risks of LTFU for ART initiation in later years (2006-2009: SHR 2.38; 95% CI 1.93-2.94; and 2010-2011: SHR 4.26; 95% CI 3.17-5.73) compared with 2003-2005. CONCLUSIONS: The long-term LTFU rate in our cohort was low, with older age being associated with LTFU. The increased risk of LTFU with later years of ART initiation in the 6-month analysis, but not the 12-month analysis, implies that there was a possible move towards longer HIV clinic scheduling in Asia.


Assuntos
Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/tratamento farmacológico , Perda de Seguimento , Adulto , Fatores Etários , Ásia/epidemiologia , Contagem de Linfócito CD4 , Feminino , Seguimentos , Infecções por HIV/imunologia , Humanos , Incidência , Masculino , Adesão à Medicação/estatística & dados numéricos , Medição de Risco
19.
PLoS One ; 14(4): e0215759, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31034482

RESUMO

To expand our knowledge of lipid and fatty acid (FA) biosynthesis in marine cnidarians, polar lipidomes of hydrocorals were studied for the first time and then compared with those of soft corals from tropical and boreal regions. The structure and content of FAs and molecular species of ethanolamine, choline, serine, and inositol glycerophospholipids (PE, PC, PS, and PI, respectively), and ceramide aminoethylphosphonate (CAEP) in tropical hydrocorals (Millepora platyphylla, M. dichotoma) and the cold-water hydrocoral Allopora steinegeri were determined by chromatography and mass spectrometry. All soft corals and cold-water hydrocorals are characterized by a considerable amount of C20 polyunsaturated FAs (PUFAs) elongated into C22 PUFAs. In the Millepora species, the high level of 22:5n-6 and 22:6n-3 against the background of the extremely low level of C20 PUFAs may be explained by a high activity of rare Δ4 desaturase. In contrast to hydrocorals, soft corals are able to elongate and further desaturate C22 PUFAs into C24 PUFAs. Allopora and soft corals use C20 PUFAs mainly for the synthesis of PE and PC. The molecular species of PS of soft corals concentrate C24 PUFAs, while in Allopora and Millepora the PS molecules are mainly based on 22:4n-6 and 22:5n-6 acyl groups, respectively. Short acyl groups (C14) dominate the CAEP molecules of Allopora. In all the animals compared, most molecular species of PE and PC are ether lipids, but diacyl molecular species dominate PI. Hydrocorals and tropical soft corals contain diacyl and ether PS molecules, respectively, whereas cold-water soft corals contain a mixture of these PS forms. The high similarity of the alkyl/acyl compositions indicates a possible biosynthetic relationship between PS and PI in hydrocorals. The data obtained in our study will provide a resource to further investigate the lipid metabolism in marine invertebrates.


Assuntos
Antozoários/metabolismo , Recifes de Corais , Fosfolipídeos/metabolismo , Animais , Antozoários/química , Antozoários/classificação , Clima Frio , Ecossistema , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Glicerofosfolipídeos/química , Glicerofosfolipídeos/metabolismo , Lipidômica , Fosfolipídeos/química , Fosfolipídeos/classificação , Especificidade da Espécie , Clima Tropical
20.
Antivir Ther ; 24(4): 271-279, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30833516

RESUMO

BACKGROUND: We aimed to project the 10-year future incidence of cardiovascular disease (CVD) and model several intervention scenarios based on a multi-site Asian HIV-positive cohort. METHODS: Analyses were based on patients recruited to the TREAT Asia HIV Observational Database (TAHOD), consisting of 21 sites in 12 countries. Patients on triple antiretroviral therapy (ART) were included if they were alive, without previous CVD, and had data on CVD risk factors. Annual new CVD events for 2019-2028 were estimated with the D:A:D equation, accounting for age- and sex-adjusted mortality. Modelled intervention scenarios were treatment of high total cholesterol, low high-density lipoprotein cholesterol (HDL) or high blood pressure, abacavir or lopinavir substitution, and smoking cessation. RESULTS: Of 3,703 included patients, 69% were male, median age was 46 (IQR 40-53) years and median time since ART initiation was 9.8 years (IQR 7.5-14.1). Cohort incidence rates of CVD were projected to increase from 730 per 100,000 person-years (pys) in 2019 to 1,432 per 100,000 pys in 2028. In the modelled intervention scenarios, most events can be avoided by smoking cessation, abacavir substitution, lopinavir substitution, decreasing total cholesterol, treating high blood pressure and increasing HDL. CONCLUSIONS: Our projections suggest a doubling of CVD incidence rates in Asian HIV-positive adults in our cohort. An increase in CVD can be expected in any ageing population, however, according to our models, this can be close to averted by interventions. Thus, there is an urgent need for risk screening and integration of HIV and CVD programmes to reduce the future CVD burden.


Assuntos
Doenças Cardiovasculares/epidemiologia , Infecções por HIV/epidemiologia , Adulto , Algoritmos , Terapia Antirretroviral de Alta Atividade , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/mortalidade , Comorbidade , Bases de Dados Factuais , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Prognóstico
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