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1.
Nat Commun ; 15(1): 4400, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38782898

RESUMO

Digestive Chagas disease (DCD) is an enteric neuropathy caused by Trypanosoma cruzi infection. There is a lack of evidence on the mechanism of pathogenesis and rationales for treatment. We used a female C3H/HeN mouse model that recapitulates key clinical manifestations to study how infection dynamics shape DCD pathology and the impact of treatment with the front-line, anti-parasitic drug benznidazole. Curative treatment 6 weeks post-infection resulted in sustained recovery of gastrointestinal transit function, whereas treatment failure led to infection relapse and gradual return of DCD symptoms. Neuro/immune gene expression patterns shifted from chronic inflammation to a tissue repair profile after cure, accompanied by increased cellular proliferation, glial cell marker expression and recovery of neuronal density in the myenteric plexus. Delaying treatment until 24 weeks post-infection led to partial reversal of DCD, suggesting the accumulation of permanent tissue damage over the course of chronic infection. Our study shows that murine DCD pathogenesis is sustained by chronic T. cruzi infection and is not an inevitable consequence of acute stage denervation. The risk of irreversible enteric neuromuscular tissue damage and dysfunction developing highlights the importance of prompt diagnosis and treatment. These findings support the concept of treating asymptomatic, T. cruzi-infected individuals with benznidazole to prevent DCD development.


Assuntos
Doença de Chagas , Modelos Animais de Doenças , Sistema Nervoso Entérico , Camundongos Endogâmicos C3H , Nitroimidazóis , Tripanossomicidas , Trypanosoma cruzi , Animais , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Feminino , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Nitroimidazóis/farmacologia , Nitroimidazóis/uso terapêutico , Trypanosoma cruzi/efeitos dos fármacos , Camundongos , Sistema Nervoso Entérico/efeitos dos fármacos , Regeneração Nervosa/efeitos dos fármacos
2.
Proc Natl Acad Sci U S A ; 121(20): e2403871121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38717857

RESUMO

DNA base damage is a major source of oncogenic mutations and disruption to gene expression. The stalling of RNA polymerase II (RNAP) at sites of DNA damage and the subsequent triggering of repair processes have major roles in shaping the genome-wide distribution of mutations, clearing barriers to transcription, and minimizing the production of miscoded gene products. Despite its importance for genetic integrity, key mechanistic features of this transcription-coupled repair (TCR) process are controversial or unknown. Here, we exploited a well-powered in vivo mammalian model system to explore the mechanistic properties and parameters of TCR for alkylation damage at fine spatial resolution and with discrimination of the damaged DNA strand. For rigorous interpretation, a generalizable mathematical model of DNA damage and TCR was developed. Fitting experimental data to the model and simulation revealed that RNA polymerases frequently bypass lesions without triggering repair, indicating that small alkylation adducts are unlikely to be an efficient barrier to gene expression. Following a burst of damage, the efficiency of transcription-coupled repair gradually decays through gene bodies with implications for the occurrence and accurate inference of driver mutations in cancer. The reinitation of transcription from the repair site is not a general feature of transcription-coupled repair, and the observed data is consistent with reinitiation never taking place. Collectively, these results reveal how the directional but stochastic activity of TCR shapes the distribution of mutations following DNA damage.


Assuntos
Dano ao DNA , Reparo do DNA , RNA Polimerase II , Transcrição Gênica , RNA Polimerase II/metabolismo , RNA Polimerase II/genética , Animais , Processos Estocásticos , Camundongos , DNA/metabolismo , DNA/genética , Humanos , Alquilação , Mutação , Reparo por Excisão
3.
Nat Genet ; 56(5): 913-924, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38627597

RESUMO

How chronic mutational processes and punctuated bursts of DNA damage drive evolution of the cancer genome is poorly understood. Here, we demonstrate a strategy to disentangle and quantify distinct mechanisms underlying genome evolution in single cells, during single mitoses and at single-strand resolution. To distinguish between chronic (reactive oxygen species (ROS)) and acute (ultraviolet light (UV)) mutagenesis, we microfluidically separate pairs of sister cells from the first mitosis following burst UV damage. Strikingly, UV mutations manifest as sister-specific events, revealing mirror-image mutation phasing genome-wide. In contrast, ROS mutagenesis in transcribed regions is reduced strand agnostically. Successive rounds of genome replication over persisting UV damage drives multiallelic variation at CC dinucleotides. Finally, we show that mutation phasing can be resolved to single strands across the entire genome of liver tumors from F1 mice. This strategy can be broadly used to distinguish the contributions of overlapping cancer relevant mutational processes.


Assuntos
Dano ao DNA , Reparo do DNA , Mitose , Mutagênese , Raios Ultravioleta , Animais , Camundongos , Reparo do DNA/genética , Raios Ultravioleta/efeitos adversos , Dano ao DNA/genética , Mitose/genética , Espécies Reativas de Oxigênio/metabolismo , Mutação , Humanos
4.
Nature ; 626(8000): 799-807, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326615

RESUMO

Linking variants from genome-wide association studies (GWAS) to underlying mechanisms of disease remains a challenge1-3. For some diseases, a successful strategy has been to look for cases in which multiple GWAS loci contain genes that act in the same biological pathway1-6. However, our knowledge of which genes act in which pathways is incomplete, particularly for cell-type-specific pathways or understudied genes. Here we introduce a method to connect GWAS variants to functions. This method links variants to genes using epigenomics data, links genes to pathways de novo using Perturb-seq and integrates these data to identify convergence of GWAS loci onto pathways. We apply this approach to study the role of endothelial cells in genetic risk for coronary artery disease (CAD), and discover 43 CAD GWAS signals that converge on the cerebral cavernous malformation (CCM) signalling pathway. Two regulators of this pathway, CCM2 and TLNRD1, are each linked to a CAD risk variant, regulate other CAD risk genes and affect atheroprotective processes in endothelial cells. These results suggest a model whereby CAD risk is driven in part by the convergence of causal genes onto a particular transcriptional pathway in endothelial cells. They highlight shared genes between common and rare vascular diseases (CAD and CCM), and identify TLNRD1 as a new, previously uncharacterized member of the CCM signalling pathway. This approach will be widely useful for linking variants to functions for other common polygenic diseases.


Assuntos
Doença da Artéria Coronariana , Células Endoteliais , Estudo de Associação Genômica Ampla , Hemangioma Cavernoso do Sistema Nervoso Central , Humanos , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Predisposição Genética para Doença/genética , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Polimorfismo de Nucleotídeo Único , Epigenômica , Transdução de Sinais/genética , Herança Multifatorial
5.
Nature ; 627(8004): 636-645, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38418875

RESUMO

A hallmark of cancer is the avoidance of immune destruction. This process has been primarily investigated in locally advanced or metastatic cancer1-3; however, much less is known about how pre-malignant or early invasive tumours evade immune detection. Here, to understand this process in early colorectal cancers (CRCs), we investigated how naive colon cancer organoids that were engineered in vitro to harbour Apc-null, KrasG12D and Trp53-null (AKP) mutations adapted to the in vivo native colonic environment. Comprehensive transcriptomic and chromatin analyses revealed that the endoderm-specifying transcription factor SOX17 became strongly upregulated in vivo. Notably, whereas SOX17 loss did not affect AKP organoid propagation in vitro, its loss markedly reduced the ability of AKP tumours to persist in vivo. The small fraction of SOX17-null tumours that grew displayed notable interferon-γ (IFNγ)-producing effector-like CD8+ T cell infiltrates in contrast to the immune-suppressive microenvironment in wild-type counterparts. Mechanistically, in both endogenous Apc-null pre-malignant adenomas and transplanted organoid-derived AKP CRCs, SOX17 suppresses the ability of tumour cells to sense and respond to IFNγ, preventing anti-tumour T cell responses. Finally, SOX17 engages a fetal intestinal programme that drives differentiation away from LGR5+ tumour cells to produce immune-evasive LGR5- tumour cells with lower expression of major histocompatibility complex class I (MHC-I). We propose that SOX17 is a transcription factor that is engaged during the early steps of colon cancer to orchestrate an immune-evasive programme that permits CRC initiation and progression.


Assuntos
Adenoma , Neoplasias Colorretais , Evasão da Resposta Imune , Fatores de Transcrição SOXF , Animais , Humanos , Camundongos , Adenoma/imunologia , Adenoma/patologia , Linfócitos T CD8-Positivos/imunologia , Cromatina/genética , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Perfilação da Expressão Gênica , Interferon gama/imunologia , Organoides/imunologia , Organoides/patologia , Fatores de Transcrição SOXF/metabolismo , Microambiente Tumoral/imunologia , Mutação , Endoderma/metabolismo , Progressão da Doença
6.
Nature ; 626(7997): 194-206, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38096902

RESUMO

The LINE-1 (L1) retrotransposon is an ancient genetic parasite that has written around one-third of the human genome through a 'copy and paste' mechanism catalysed by its multifunctional enzyme, open reading frame 2 protein (ORF2p)1. ORF2p reverse transcriptase (RT) and endonuclease activities have been implicated in the pathophysiology of cancer2,3, autoimmunity4,5 and ageing6,7, making ORF2p a potential therapeutic target. However, a lack of structural and mechanistic knowledge has hampered efforts to rationally exploit it. We report structures of the human ORF2p 'core' (residues 238-1061, including the RT domain) by X-ray crystallography and cryo-electron microscopy in several conformational states. Our analyses identified two previously undescribed folded domains, extensive contacts to RNA templates and associated adaptations that contribute to unique aspects of the L1 replication cycle. Computed integrative structural models of full-length ORF2p show a dynamic closed-ring conformation that appears to open during retrotransposition. We characterize ORF2p RT inhibition and reveal its underlying structural basis. Imaging and biochemistry show that non-canonical cytosolic ORF2p RT activity can produce RNA:DNA hybrids, activating innate immune signalling through cGAS/STING and resulting in interferon production6-8. In contrast to retroviral RTs, L1 RT is efficiently primed by short RNAs and hairpins, which probably explains cytosolic priming. Other biochemical activities including processivity, DNA-directed polymerization, non-templated base addition and template switching together allow us to propose a revised L1 insertion model. Finally, our evolutionary analysis demonstrates structural conservation between ORF2p and other RNA- and DNA-dependent polymerases. We therefore provide key mechanistic insights into L1 polymerization and insertion, shed light on the evolutionary history of L1 and enable rational drug development targeting L1.


Assuntos
Endonucleases , Elementos Nucleotídeos Longos e Dispersos , DNA Polimerase Dirigida por RNA , Transcrição Reversa , Humanos , Microscopia Crioeletrônica , Endonucleases/química , Endonucleases/genética , Endonucleases/metabolismo , Elementos Nucleotídeos Longos e Dispersos/genética , RNA/genética , DNA Polimerase Dirigida por RNA/química , DNA Polimerase Dirigida por RNA/genética , DNA Polimerase Dirigida por RNA/metabolismo , Cristalografia por Raios X , DNA/biossíntese , DNA/genética , Imunidade Inata , Interferons/biossíntese
7.
ACS Environ Au ; 3(6): 342-347, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38028741

RESUMO

Plastic waste is a critical global issue, yet current strategies to avoid committing plastic waste to landfills include incineration, gasification, or pyrolysis high carbon emitting and energy consuming approaches. However, plastic waste can become a resource instead of a problem if high value products, such as fine chemicals and liquid fuel molecules, can be liberated from controlled its decomposition. This letter presents proof of concept on a low-cost, low energy approach to controlled decomposition of plastic, photocatalytic hydrolysis. This approach integrates photolysis and hydrolysis, both slow natural decomposition processes, with a photocatalytic process. The photocatalyst, α-Fe2O3, is embedded into a polylactic acid (PLA) plastic matrix. The photocatalyst/plastic composite is then immersed in water and subjected to low-energy (25 W) UV light for 90 h. The monomer lactide is produced as the major product. α-Fe2O3 (6.9 wt %) was found to accelerate the PLA degradation pathway, achieving 32% solid transformation into liquid phase products, in comparison to PLA on its own, which was found to not decompose, using the same conditions. This highlights a low energy route toward plastic waste upgrade and valorization that is less carbon intensive than pyrolysis and faster than natural degradation. By directly comparing a 25 W (0.025 kWh) UV bulb with a 13 kWh furnace, the photocatalytic reaction would directly consume 520× less energy than a conventional thermochemical pathway. Furthermore, this technology can be extended and applied to other plastics, and other photocatalysts can be used.

8.
PLoS Pathog ; 19(11): e1011627, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37956215

RESUMO

Benznidazole is the front-line drug used to treat infections with Trypanosoma cruzi, the causative agent of Chagas disease. However, for reasons that are unknown, treatment failures are common. When we examined parasites that survived benznidazole treatment in mice using highly sensitive in vivo and ex vivo bioluminescence imaging, we found that recrudescence is not due to persistence of parasites in a specific organ or tissue that preferentially protects them from drug activity. Surviving parasites are widely distributed and located in host cells where the vast majority contained only one or two amastigotes. Therefore, infection relapse does not arise from a small number of intact large nests. Rather, persisters are either survivors of intracellular populations where co-located parasites have been killed, or amastigotes in single/low-level infected cells exist in a state where they are less susceptible to benznidazole. To better assess the nature of parasite persisters, we exposed infected mammalian cell monolayers to a benznidazole regimen that reduces the intracellular amastigote population to <1% of the pre-treatment level. Of host cells that remained infected, as with the situation in vivo, the vast majority contained only one or two surviving intracellular amastigotes. Analysis, based on non-incorporation of the thymidine analogue EdU, revealed these surviving parasites to be in a transient non-replicative state. Furthermore, treatment with benznidazole led to widespread parasite DNA damage. When the small number of parasites which survive in mice after non-curative treatment were assessed using EdU labelling, this revealed that these persisters were also initially non-replicative. A possible explanation could be that triggering of the T. cruzi DNA damage response pathway by the activity of benznidazole metabolites results in exit from the cell cycle as parasites attempt DNA repair, and that metabolic changes associated with non-proliferation act to reduce drug susceptibility. Alternatively, a small percentage of the parasite population may pre-exist in this non-replicative state prior to treatment.


Assuntos
Doença de Chagas , Nitroimidazóis , Parasitos , Tripanossomicidas , Trypanosoma cruzi , Animais , Camundongos , Trypanosoma cruzi/genética , Nitroimidazóis/farmacologia , Doença de Chagas/parasitologia , Dano ao DNA , Tripanossomicidas/farmacologia , Tripanossomicidas/metabolismo , Mamíferos
9.
Cell Genom ; 3(11): 100419, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38020974

RESUMO

We describe the complete synthesis, assembly, debugging, and characterization of a synthetic 404,963 bp chromosome, synIX (synthetic chromosome IX). Combined chromosome construction methods were used to synthesize and integrate its left arm (synIXL) into a strain containing previously described synIXR. We identified and resolved a bug affecting expression of EST3, a crucial gene for telomerase function, producing a synIX strain with near wild-type fitness. To facilitate future synthetic chromosome consolidation and increase flexibility of chromosome transfer between distinct strains, we combined chromoduction, a method to transfer a whole chromosome between two strains, with conditional centromere destabilization to substitute a chromosome of interest for its native counterpart. Both steps of this chromosome substitution method were efficient. We observed that wild-type II tended to co-transfer with synIX and was co-destabilized with wild-type IX, suggesting a potential gene dosage compensation relationship between these chromosomes.

10.
Pathogens ; 12(11)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38003828

RESUMO

Chronic Chagas cardiomyopathy (CCC) results from infection with the protozoan parasite Trypanosoma cruzi and is a prevalent cause of heart disease in endemic countries. We previously found that cardiac fibrosis can vary widely in C3H/HeN mice chronically infected with T. cruzi JR strain, mirroring the spectrum of heart disease in humans. In this study, we examined functional cardiac abnormalities in this host:parasite combination to determine its potential as an experimental model for CCC. We utilised electrocardiography (ECG) to monitor T. cruzi-infected mice and determine whether ECG markers could be correlated with cardiac function abnormalities. We found that the C3H/HeN:JR combination frequently displayed early onset CCC indicators, such as sinus bradycardia and right bundle branch block, as well as prolonged PQ, PR, RR, ST, and QT intervals in the acute stage. Our model exhibited high levels of cardiac inflammation and enhanced iNOS expression in the acute stage, but denervation did not appear to have a role in pathology. These results demonstrate the potential of the C3H/HeN:JR host:parasite combination as a model for CCC that could be used for screening new compounds targeted at cardiac remodelling and for examining the potential of antiparasitic drugs to prevent or alleviate CCC development and progression.

12.
J Med Chem ; 66(18): 13043-13057, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37722077

RESUMO

We designed and synthesized a series of symmetric bis-6-amidino-benzothiazole derivatives with aliphatic central units and evaluated their efficacy against bloodstream forms of the African trypanosome Trypanosoma brucei. Of these, a dicationic benzothiazole compound (9a) exhibited sub-nanomolar in vitro potency with remarkable selectivity over mammalian cells (>26,000-fold). Unsubstituted 5-amidine groups and a cyclohexyl spacer were the crucial determinants of trypanocidal activity. In all cases, mice treated with a single dose of 20 mg kg-1 were cured of stage 1 trypanosomiasis. The compound displayed a favorable in vitro ADME profile, with the exception of low membrane permeability. However, we found evidence that uptake by T. brucei is mediated by endocytosis, a process that results in lysosomal sequestration. The compound was also active in low nanomolar concentrations against cultured asexual forms of the malaria parasite Plasmodium falciparum. Therefore, 9a has exquisite cross-species efficacy and represents a lead compound with considerable therapeutic potential.


Assuntos
Tripanossomicidas , Trypanosoma brucei brucei , Trypanosoma , Tripanossomíase Africana , Tripanossomíase , Camundongos , Animais , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Africana/parasitologia , Tripanossomíase/tratamento farmacológico , Benzotiazóis/farmacologia , Benzotiazóis/uso terapêutico , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Mamíferos
13.
Cancer Discov ; 13(12): 2532-2547, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-37698949

RESUMO

Improved biomarkers are needed for early cancer detection, risk stratification, treatment selection, and monitoring treatment response. Although proteins can be useful blood-based biomarkers, many have limited sensitivity or specificity for these applications. Long INterspersed Element-1 (LINE-1) open reading frame 1 protein (ORF1p) is a transposable element protein overexpressed in carcinomas and high-risk precursors during carcinogenesis with negligible expression in normal tissues, suggesting ORF1p could be a highly specific cancer biomarker. To explore ORF1p as a blood-based biomarker, we engineered ultrasensitive digital immunoassays that detect mid-attomolar (10-17 mol/L) ORF1p concentrations in plasma across multiple cancers with high specificity. Plasma ORF1p shows promise for early detection of ovarian cancer, improves diagnostic performance in a multianalyte panel, provides early therapeutic response monitoring in gastroesophageal cancers, and is prognostic for overall survival in gastroesophageal and colorectal cancers. Together, these observations nominate ORF1p as a multicancer biomarker with potential utility for disease detection and monitoring. SIGNIFICANCE: The LINE-1 ORF1p transposon protein is pervasively expressed in many cancers and is a highly specific biomarker of multiple common, lethal carcinomas and their high-risk precursors in tissue and blood. Ultrasensitive ORF1p assays from as little as 25 µL plasma are novel, rapid, cost-effective tools in cancer detection and monitoring. See related commentary by Doucet and Cristofari, p. 2502. This article is featured in Selected Articles from This Issue, p. 2489.


Assuntos
Carcinoma , Neoplasias Ovarianas , Feminino , Humanos , Elementos Nucleotídeos Longos e Dispersos , Proteínas/genética , Biomarcadores Tumorais , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética
14.
Pharmaceuticals (Basel) ; 16(7)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37513957

RESUMO

Flaviviridae infections, such as those caused by hepatitis C (HCV) and dengue viruses (DENVs), represent global health risks. Infected people are in danger of developing chronic liver failure or hemorrhagic fever, both of which can be fatal if not treated. The tropical parasites Trypanosoma brucei and Trypanosoma cruzi cause enormous socioeconomic burdens in Sub-Saharan Africa and Latin America. Anti-HCV chemotherapy has severe adverse effects and is expensive, whereas dengue has no clinically authorized treatment. Antiparasitic medicines are often toxic and difficult to administer, and treatment failures are widely reported. There is an urgent need for new chemotherapies. Based on our previous research, we have undertaken structural modification of lead compound V with the goal of producing derivatives with both antiviral and trypanocidal activity. The novel spirocarbocyclic-substituted hydantoin analogs were designed, synthesized, and tested for antiviral activity against three HCV genotypes (1b, 3a, 4a), DENV, yellow fever virus (YFV), and two trypanosome species (T. brucei, T. cruzi). The optimization was successful and led to compounds with significant antiviral and trypanocidal activity and exceptional selectivity. Several modifications were made to further investigate the structure-activity relationships (SARs) and confirm the critical role of lipophilicity and conformational degrees of freedom.

15.
Crit Care Med ; 51(12): e264-e268, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37449964

RESUMO

OBJECTIVES: Trimethoprim-sulfamethoxazole (TMP-SMX)-associated severe acute respiratory distress syndrome (ARDS) has gone underrecognized. We propose the first disease definition and clinical evaluation for a novel adverse drug reaction (ADR) based on a series of recently identified rare cases of life-threatening ADRs. DESIGN: A retrospective study was conducted. All medical records were evaluated. Available pathology samples were sent to Massachusetts General for clinical consultation. Blood samples from surviving patients were obtained and human leukocyte antigen (HLA) analysis was performed by the Children's Mercy Hospital Genomic Center and Vanderbilt University Medical Center. SETTING: U.S. ICUs, 1996-2021. PATIENTS: Nineteen young patients (10-37) were identified. Patients were previously healthy, with no preexisting pulmonary disease, no other cause for respiratory failure, and no chronic history of smoking/vaping. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Through our retrospective analysis, we analyzed clinical characteristics associated with TMP-SMX. Pathology samples were reviewed, and HLA analysis was performed on available samples by the study team or as standard of care at treatment hospitals in some cases. In 19 critically ill patients, we identified a pattern of severe respiratory failure requiring ICU admission, mechanical ventilation, and frequent extracorporeal membrane oxygenation use. We describe the first three-part clinical diagnosis and evaluation strategy: 1) Clinical definition: Unexplained severe respiratory failure in a patient receiving greater than or equal to 6 days of TMP-SMX at treatment dose (not prophylaxis). TMP-SMX ARDS is a diagnosis of exclusion. 2) Genetic association: One hundred percent of currently available TMP-SMX respiratory failure patient genomic data, ( n = 11) have been carriers of both HLA-B*07:02 and HLA-C*07:02 alleles. HLA allele evaluation could be considered in patients with suspected TMP-SMX respiratory failure. 3) Lung pathology: A unique pulmonary pathologic pattern of lung injury termed diffuse alveolar injury with delayed epithelialization has been observed in these cases. In suspected cases, surgical lung biopsy early in the clinical course could be considered. CONCLUSIONS: TMP-SMX is a commonly prescribed antibiotic. However, we find it imperative to share this relatively rare but life-threatening condition with clinicians as the mortality rate approaches 40%.


Assuntos
Síndrome do Desconforto Respiratório , Insuficiência Respiratória , Criança , Humanos , Combinação Trimetoprima e Sulfametoxazol/efeitos adversos , Estudos Retrospectivos , Antibacterianos/efeitos adversos , Síndrome do Desconforto Respiratório/tratamento farmacológico , Insuficiência Respiratória/induzido quimicamente , Insuficiência Respiratória/tratamento farmacológico
16.
Science ; 380(6650): 1118-1120, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37319228

RESUMO

Impacts on ecology, health, energy, and climate are critical.


Assuntos
Poluição Luminosa , Clima , Ecologia , Poluição Luminosa/efeitos adversos , Poluição Luminosa/prevenção & controle , Iluminação
17.
ChemMedChem ; 18(18): e202300261, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37376962

RESUMO

Novel benzo[b]thienyl- and 2,2'-bithienyl-derived benzothiazoles and benzimidazoles were synthesized to study their antiproliferative and antitrypanosomal activities in vitro. Specifically, we assessed the impact that amidine group substitutions and the type of thiophene backbone have on biological activity. In general, the benzothiazole derivatives were more active than their benzimidazole analogs as both antiproliferative and antitrypanosomal agents. The 2,2'-bithienyl-substituted benzothiazoles with unsubstituted and 2-imidazolinyl amidine showed the most potent antitrypanosomal activity, and the greatest selectivity was observed for the benzimidazole derivatives bearing isopropyl, unsubstituted and 2-imidazolinyl amidine. The 2,2'-bithiophene derivatives showed most selective antiproliferative activity. Whereas the all 2,2'-bithienyl-substituted benzothiazoles were selectively active against lung carcinoma, the benzimidazoles were selective against cervical carcinoma cells. The compounds with an unsubstituted amidine group also produced strong antiproliferative effects. The more pronounced antiproliferative activity of the benzothiazole derivatives was attributed to different cytotoxicity mechanisms. Cell cycle analysis, and DNA binding experiments provide evidence that the benzimidazoles target DNA, whereas the benzothiazoles have a different cellular target because they are localized in the cytoplasm and do not interact with DNA.


Assuntos
Antineoplásicos , Carcinoma , Humanos , Antineoplásicos/química , Linhagem Celular Tumoral , Benzotiazóis/química , DNA/metabolismo , Benzimidazóis/química , Amidinas/farmacologia , Amidinas/química , Relação Estrutura-Atividade , Proliferação de Células
18.
Mob DNA ; 14(1): 5, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165451

RESUMO

BACKGROUND: Patients with systemic lupus erythematosus (SLE) have autoantibodies against the L1-encoded open-reading frame 1 protein (ORF1p). Here, we report (i) which immune cells ORF1p emanates from, (ii) which L1 loci are transcriptionally active, (iii) whether the cells express L1-dependent interferon and interferon-stimulated genes, and (iv) the effect of inhibition of L1 ORF2p by reverse transcriptase inhibitors. RESULTS: L1 ORF1p was detected by flow cytometry primarily in SLE CD66b+CD15+ regular and low-density granulocytes, but much less in other immune cell lineages. The amount of ORF1p was higher in neutrophils from patients with SLE disease activity index (SLEDAI) > 6 (p = 0.011) compared to patients with inactive disease, SLEDAI < 4. Patient neutrophils transcribed seven to twelve human-specific L1 loci (L1Hs), but only 3 that are full-length and with an intact ORF1. Besides serving as a source of detectable ORF1p, the most abundant transcript encoded a truncated ORF2p reverse transcriptase predicted to remain cytosolic, while the two other encoded an intact full-length ORF2p. A number of genes encoding proteins that influence L1 transcription positively or negatively were altered in patients, particularly those with active disease, compared to healthy controls. Components of nucleic acid sensing and interferon induction were also altered. SLE neutrophils also expressed type I interferon-inducible genes and interferon ß, which were substantially reduced after treatment of the cells with drugs known to inhibit ORF2p reverse transcriptase activity. CONCLUSIONS: We identified L1Hs loci that are transcriptionally active in SLE neutrophils, and a reduction in the epigenetic silencing mechanisms that normally counteract L1 transcription. SLE neutrophils contained L1-encoded ORF1p protein, as well as activation of the type I interferon system, which was inhibited by treatment with reverse transcriptase inhibitors. Our findings will enable a deeper analysis of L1 dysregulation and its potential role in SLE pathogenesis.

19.
Nanomaterials (Basel) ; 13(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37111019

RESUMO

Recyclable PdCu single atom alloys supported on Al2O3 were applied to the selective hydrogenation of crotonaldehyde to elucidate the minimum number of Pd atoms required to facilitate the sustainable transformation of an α,ß-unsaturated carbonyl molecule. It was found that, by diluting the Pd content of the alloy, the reaction activity of Cu nanoparticles can be accelerated, enabling more time for the cascade conversion of butanal to butanol. In addition, a significant increase in the conversion rate was observed, compared to bulk Cu/Al2O3 and Pd/Al2O3 catalysts when normalising for Cu and Pd content, respectively. The reaction selectivity over the single atom alloy catalysts was found to be primarily controlled by the Cu host surface, mainly leading to the formation of butanal but at a significantly higher rate than the monometallic Cu catalyst. Low quantities of crotyl alcohol were observed over all Cu-based catalysts but not for the Pd monometallic catalyst, suggesting that it may be a transient species converted immediately to butanol and or isomerized to butanal. These results demonstrate that fine-tuning the dilution of PdCu single atom alloy catalysts can leverage the activity and selectivity enhancement, and lead to cost-effective, sustainable, and atom-efficient alternatives to monometallic catalysts.

20.
Acta Ophthalmol ; 101(6): 627-635, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36879397

RESUMO

PURPOSE: This study was performed with the aim of finding a more convenient and less time-consuming method to diagnose retinal breaks in posterior vitreous detachment (PVD) patients. METHODS: A prospective double-blind observational case study was performed with patients who were admitted to the Eye Emergency Department Sahlgrenska University Hospital with PVD symptoms and approved to participate in the study (n = 128). Standard slit lamp examination was compared with images from a Zeiss Clarus 700 ultra-wide-field camera (UWFC). Patients were examined and photographed by an independent operator. Data and image review was performed by three independent reviewers with varying experience. Retinal break detection with the two different methods (detailed eye examination by well-trained ophthalmologist and UWFC evaluations) was analysed statistically. RESULTS: After excluding diagnoses other than PVD as well as unclear images due to cataracts, vitreous bleeding, etc., a total of 103 eyes with PVD were evaluated. A total of 38 ruptures in 25 patients were detected by routine examination and were subjected to laser treatment. UWFC images were reviewed by three ophthalmology consultants and compared with routine examinations. Sensitivity values in detecting retinal ruptures in UWFC images of the three reviewers were 0.89, 0.87 and 0.79, and specificity values were 0.88, 0.86 and 0.93 (kappa values: 0.742, 0.689 and 0.728) respectively. CONCLUSION: Although there have been rapid developments in imaging with UWFC in recent years and it is a very promising method for the future, routine clinical examination is still the only valid method for the detection of retinal tears today.


Assuntos
Descolamento Retiniano , Perfurações Retinianas , Descolamento do Vítreo , Humanos , Diagnóstico por Imagem , Estudos Prospectivos , Retina/diagnóstico por imagem , Descolamento Retiniano/diagnóstico , Perfurações Retinianas/diagnóstico , Perfurações Retinianas/cirurgia , Descolamento do Vítreo/diagnóstico
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