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1.
NPJ Metab Health Dis ; 2(1): 20, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39149696

RESUMO

Histone deacetylases (HDACs) have a wide range of targets and can rewire both the chromatin and lipidome of cancer cells. In this study, we show that valproic acid (VPA), a brain penetrant anti-seizure medication and histone deacetylase inhibitor, inhibits the growth of IDH1 mutant tumors in vivo and in vitro, with at least some selectivity over IDH1 wild-type tumors. Surprisingly, genes upregulated by VPA showed no enhanced chromatin accessibility at the promoter, but there was a correlation between VPA-downregulated genes and diminished promoter chromatin accessibility. VPA inhibited the transcription of lipogenic genes and these lipogenic genes showed significant decreases in promoter chromatin accessibility only in the IDH1 MT glioma cell lines tested. VPA inhibited the mTOR pathway and a key lipogenic gene, fatty acid synthase (FASN). Both VPA and a selective FASN inhibitor TVB-2640 rewired the lipidome and promoted apoptosis in an IDH1 MT but not in an IDH1 WT glioma cell line. We further find that HDACs are involved in the regulation of lipogenic genes and HDAC6 is particularly important for the regulation of FASN in IDH1 MT glioma. Finally, we show that FASN knockdown alone and VPA in combination with FASN knockdown significantly improved the survival of mice in an IDH1 MT primary orthotopic xenograft model in vivo. We conclude that targeting fatty acid metabolism through HDAC inhibition and/or FASN inhibition may be a novel therapeutic opportunity in IDH1 mutant gliomas.

3.
Mol Ecol Resour ; : e14010, 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39155537

RESUMO

Field-collected specimens were used to obtain nine high-quality genome assemblies from a total of 10 insect species native to prairies and savannas of central Illinois (USA): Mellilla xanthometata (Lepidoptera: Geometridae), Stenolophus ochropezus (Coleoptera: Carabidae), Forcipata loca (Hemiptera: Cicadellidae), Coelinius sp. (Hymenoptera: Braconidae), Thaumatomyia glabra (Diptera: Chloropidae), Brachynemurus abdominalus (Neuroptera: Myrmeleontidae), Catonia carolina (Hemiptera: Achilidae), Oncometopia orbona (Hemiptera: Cicadellidae), Flexamia atlantica (Hemiptera: Cicadellidae) and Stictocephala bisonia (Hemiptera: Membracidae). Sequencing library preparation from single specimens was successful despite extremely small DNA yields (<0.1 µg) for some samples. Additional sequencing and assembly workflows were adapted to each sample depending on the initial DNA yield. PacBio circular consensus (CCS/HiFi) or continuous long reads (CLR) libraries were used to sequence DNA fragments up to 50 kb in length, with Illumina sequenced linked-reads (TellSeq libraries) and Omni-C libraries used for scaffolding and gap-filling. Assembled genome sizes ranged from 135 MB to 3.2 GB. The number of assembled scaffolds ranged from 47 to >13,000, with the longest scaffold per assembly ranging from ~23 to 439 Mb. Genome completeness was high, with BUSCO scores ranging from 85.5% completeness for the largest genome (Stictocephala bisonia) to 98.8% completeness for the smallest genome (Coelinius sp.). The unique content was estimated using RepeatMasker and GenomeScope2, which ranged from 50.7% to 75.8% and roughly decreased with increasing genome size. Structural annotation predicted a range of 19,281-72,469 protein models for sequenced species. Sequencing costs per genome at the time ranged from US$3-5k, averaged ~1600 CPU-hours on a high-performance cluster and required approximately 14 h of bioinformatics analyses with samples using PacBio HiFi data. Most assemblies would benefit from further manual curation to correct possible scaffold misjoins and translocations suggested by off-diagonal or depleted signals in Omni-C contact maps.

4.
bioRxiv ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39131340

RESUMO

Small extracellular vesicles (sEVs) are emerging as critical mediators of intercellular communication in the tumor microenvironment (TME). Here, we investigate the mechanisms by which sEVs derived from neutrophils treated with the cholesterol metabolite, 27-hydroxycholesterol (27HC), influence breast cancer progression. sEVs released from 27HC treated neutrophils enhance epithelial-mesenchymal transition (EMT) and stem-like properties in breast cancer cells, resulting in loss of adherence, increased migratory capacity and resistance to cytotoxic chemotherapy. Decreased microRNAs (miRs) within the sEVs resulted in activation of the WNT/ß-catenin signaling pathway in recipient cells and suggest that this may be a predominant pathway for stem-like phenotype and EMT. Our findings underscore a novel mechanism by which 27HC-modulated neutrophils contribute to breast cancer pathophysiology through EV-mediated intercellular communication, suggesting potential therapeutic targets in cancer treatment.

5.
Bioconjug Chem ; 35(7): 971-980, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38958375

RESUMO

Conventional serum markers often fail to accurately detect cholestasis accompanying many liver diseases. Although elevation in serum bile acid (BA) levels sensitively reflects impaired hepatobiliary function, other factors altering BA pool size and enterohepatic circulation can affect these levels. To develop fluorescent probes for extracorporeal noninvasive hepatobiliary function assessment by real-time monitoring methods, 1,3-dipolar cycloaddition reactions were used to conjugate near-infrared (NIR) fluorochromes with azide-functionalized BA derivatives (BAD). The resulting compounds (NIRBADs) were chromatographically (FC and PTLC) purified (>95%) and characterized by fluorimetry, 1H NMR, and HRMS using ESI ionization coupled to quadrupole TOF mass analysis. Transport studies using CHO cells stably expressing the BA carrier NTCP were performed by flow cytometry. Extracorporeal fluorescence was detected in anesthetized rats by high-resolution imaging analysis. Three NIRBADs were synthesized by conjugating alkynocyanine 718 with cholic acid (CA) at the COOH group via an ester (NIRBAD-1) or amide (NIRBAD-3) spacer, or at the 3α-position by a triazole link (NIRBAD-2). NIRBADs were efficiently taken up by cells expressing NTCP, which was inhibited by taurocholic acid (TCA). Following i.v. administration of NIRBAD-3 to rats, liver uptake and consequent release of NIR fluorescence could be extracorporeally monitored. This transient organ-specific handling contrasted with the absence of release to the intestine of alkynocyanine 718 and the lack of hepatotropism observed with other probes, such as indocyanine green. NIRBAD-3 administration did not alter serum biomarkers of hepatic and renal toxicity. NIRBADs can serve as probes to evaluate hepatobiliary function by noninvasive extracorporeal methods.


Assuntos
Ácidos e Sais Biliares , Corantes Fluorescentes , Fígado , Animais , Ácidos e Sais Biliares/química , Corantes Fluorescentes/química , Ratos , Fígado/metabolismo , Fígado/diagnóstico por imagem , Células CHO , Cricetulus , Testes de Função Hepática/métodos , Masculino , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Ratos Sprague-Dawley , Fluorescência
6.
Chempluschem ; : e202400410, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950125

RESUMO

Rh(III) and Ru(II) complexes, [RhCl2(κ4-N2N'P-L)][SbF6] (1) and [RuCl2(κ4-N2N'P-L)] (2), were synthesised using the tetradentate ligand L (L=N,N-bis[(pyridin-2-yl)methyl]-[2-(diphenylphosphino)phenyl]methanamine). In each case only one diastereomer is detected, featuring cis-disposed pyridine groups. The chloride ligand trans to pyridine can be selectively abstracted by AgSbF6, with the ruthenium complex (2) reacting more readily at room temperature compared to the rhodium complex (1) which requires elevated temperatures. Rhodium complexes avoid the second chloride abstraction, whereas ruthenium complexes can form the chiral bisacetonitrile complex [Ru(κ4-N2N'P-L)(NCMe)2][SbF6]2 (5) upon corresponding treatment with AgSbF6. The complex [RhCl2(κ4-N2N'P-L)][SbF6] (1) has also been used to synthesise polymetallic species, such as the tetrametallic complex [{RhCl2(κ4-N2N'P-L)}2(µ-Ag)2][SbF6]4 (6) which was formed with complete diastereoselectivity and chiral molecular self-recognition. In addition, a stable bimetallic mixed-valence complex [{Rh(κ4-N2N'P-L)}{Rh(COD)}(µ-Cl)2][SbF6]2 (7) (COD=cyclooctadiene) was synthesised. These results highlight the significant differences in chloride lability between Rh3+ and Ru2+ complexes and demonstrate the potential for complexes to act as catalyst precursors and ligands in further chemistry applications.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38898570

RESUMO

Backgrounds/Aims: Thirty percent of liver grafts in donors after brain death (DBD) in Spain are rejected by procurement surgeons owing to marginal graft quality. Poor donor indocyanine green (ICG) clearance has been associated with graft discard and malfunction. This study aimed to internally and externally validate the predictive value of ICG-plasma disappearance rate (ICG-PDR) to reject grafts before donation and set a cut-off to avoid missing any potential effective donors. Methods: Between March 2017 and August 2023, ICG clearance test was performed immediately before procurement in 71 DBD. The surgeon was blinded to test results. Univariate and multivariate analyses were performed to detect independent predictors of graft discard. Discrimination and calibration of predictors were assessed and a cut-off with 100% specificity was set. External validation was performed on 17 donors evaluated by three other transplantation teams. Results: In the training cohort, 30 of 71 grafts were discarded for transplantation. ICG-PDR was the only donor variable independently associated with graft discard. The area under receiver operating characteristic curve for ICG-PDR was 0.875 (95% confidence interval: 0.768-0.947) and good calibration was observed. Below a PDR of 13.5%/min, no graft was accepted for transplantation. These results were successfully validated using the external cohort of donors. Conclusions: ICG clearance test performed in DBD was internally and externally validated to predict liver graft discard. It could be used as a screening tool before donation to avoid unnecessary costs of travel and human resources.

8.
Redox Biol ; 75: 103249, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38945076

RESUMO

Tumors develop in an oxidative environment characterized by peroxynitrite production and downstream protein tyrosine (Y) nitration. We showed that tyrosine nitration supports schwannoma cell proliferation and regulates cell metabolism in the inheritable tumor disorder NF2-related Schwannomatosis (NF2-SWN). Here, we identified the chaperone Heat shock protein 90 (Hsp90) as the first nitrated protein that acts as a metabolic switch to promote schwannoma cell proliferation. Doubling the endogenous levels of nitrated Hsp90 in schwannoma cells or supplementing nitrated Hsp90 into normal Schwann cells increased their proliferation. Metabolically, nitration on either Y33 or Y56 conferred Hsp90 distinct functions; nitration at Y33 (Hsp90NY33) down-regulated mitochondrial oxidative phosphorylation, while nitration at Y56 (Hsp90NY56) increased glycolysis by activating the purinergic receptor P2X7 in both schwannoma and normal Schwann cells. Hsp90NY33 and Hsp90NY56 showed differential subcellular and spatial distribution corresponding with their metabolic and proliferative functions in schwannoma three-dimensional cell culture models. Collectively, these results underscore the role of tyrosine nitration as a post-translational modification regulating critical cellular processes. Nitrated proteins, particularly nitrated Hsp90, emerge as a novel category of tumor-directed therapeutic targets.


Assuntos
Proliferação de Células , Proteínas de Choque Térmico HSP90 , Neurilemoma , Células de Schwann , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Neurilemoma/metabolismo , Neurilemoma/patologia , Células de Schwann/metabolismo , Linhagem Celular Tumoral , Animais , Tirosina/metabolismo , Processamento de Proteína Pós-Traducional , Fosforilação Oxidativa
9.
Am J Physiol Cell Physiol ; 327(1): C11-C33, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38708523

RESUMO

In contrast to other types of cancers, there is no available efficient pharmacological treatment to improve the outcomes of patients suffering from major primary liver cancers, i.e., hepatocellular carcinoma and cholangiocarcinoma. This dismal situation is partly due to the existence in these tumors of many different and synergistic mechanisms of resistance, accounting for the lack of response of these patients, not only to classical chemotherapy but also to more modern pharmacological agents based on the inhibition of tyrosine kinase receptors (TKIs) and the stimulation of the immune response against the tumor using immune checkpoint inhibitors (ICIs). This review summarizes the efforts to develop strategies to overcome this severe limitation, including searching for novel drugs derived from synthetic, semisynthetic, or natural products with vectorial properties against therapeutic targets to increase drug uptake or reduce drug export from cancer cells. Besides, immunotherapy is a promising line of research that is already starting to be implemented in clinical practice. Although less successful than in other cancers, the foreseen future for this strategy in treating liver cancers is considerable. Similarly, the pharmacological inhibition of epigenetic targets is highly promising. Many novel "epidrugs," able to act on "writer," "reader," and "eraser" epigenetic players, are currently being evaluated in preclinical and clinical studies. Finally, gene therapy is a broad field of research in the fight against liver cancer chemoresistance, based on the impressive advances recently achieved in gene manipulation. In sum, although the present is still dismal, there is reason for hope in the non-too-distant future.


Assuntos
Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Animais , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Imunoterapia/métodos , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores de Proteínas Quinases/uso terapêutico , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/imunologia , Colangiocarcinoma/patologia , Epigênese Genética/efeitos dos fármacos
10.
J Obes ; 2024: 6997280, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38817395

RESUMO

Background: Weight loss and lifestyle interventions are the mainstay of treatment in pediatric NAFLD. There are gaps in the literature on the objective improvement in BMI to meaningfully impact NAFLD in children. Aim: To determine the decrease in BMI associated with a significant decline in ALT and other metabolic parameters. Methods: Retrospective chart review of pediatric patients with the diagnosis of NAFLD. Data were collected at the baseline and 6 and 12 months. A linear regression model was used to assess the percent change in BMI predictive of change in ALT and other metabolic parameters. Results: 281 charts were included. 71% of patients who had up to a 2.5% loss in BMI at 6 months had a decrease in ALT of up to 10 U/L compared to 43% patients who did not have a decrease in BMI up to 2.5% loss at the same time period (P=0.01). The linear regression model showed that 6-month and 12-month percent changes in BMI are predictive of 6-month and 12-month ALT changes (P=0.01 and 0.02), respectively. ALT normalization was achieved on 12% of patients with a ≥2.5% decrease in BMI at 6 months compared to 1% of patients that had no decrease of ≥2.5% decrease in BMI at 6 months (P=0.01). The mean BMI Z-score decline was 0.18 (P=0.001) in the group with a ≥2.5% decrease in BMI at 6 months. Conclusions: BMI loss of up to 2.5% and the mean BMI Z-score 0.18 are associated with a significant decrease in ALT of up to 10 U/L. BMI percent change at 6 months and 12 months is predictive of changes in ALT. These results should help guide providers in clinical practice set objective goals for the management of children with NAFLD resulting from obesity.


Assuntos
Alanina Transaminase , Índice de Massa Corporal , Hepatopatia Gordurosa não Alcoólica , Redução de Peso , Humanos , Masculino , Feminino , Estudos Retrospectivos , Criança , Adolescente , Alanina Transaminase/sangue , Obesidade Infantil/complicações , Obesidade Infantil/terapia
11.
Neurooncol Adv ; 6(1): vdae005, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38616896

RESUMO

Background: Non-enhancing (NE) infiltrating tumor cells beyond the contrast-enhancing (CE) bulk of tumor are potential propagators of recurrence after gross total resection of high-grade glioma. Methods: We leveraged single-nucleus RNA sequencing on 15 specimens from recurrent high-grade gliomas (n = 5) to compare prospectively identified biopsy specimens acquired from CE and NE regions. Additionally, 24 CE and 22 NE biopsies had immunohistochemical staining to validate RNA findings. Results: Tumor cells in NE regions are enriched in neural progenitor cell-like cellular states, while CE regions are enriched in mesenchymal-like states. NE glioma cells have similar proportions of proliferative and putative glioma stem cells relative to CE regions, without significant differences in % Ki-67 staining. Tumor cells in NE regions exhibit upregulation of genes previously associated with lower grade gliomas. Our findings in recurrent GBM paralleled some of the findings in a re-analysis of a dataset from primary GBM. Cell-, gene-, and pathway-level analyses of the tumor microenvironment in the NE region reveal relative downregulation of tumor-mediated neovascularization and cell-mediated immune response, but increased glioma-to-nonpathological cell interactions. Conclusions: This comprehensive analysis illustrates differing tumor and nontumor landscapes of CE and NE regions in high-grade gliomas, highlighting the NE region as an area harboring likely initiators of recurrence in a pro-tumor microenvironment and identifying possible targets for future design of NE-specific adjuvant therapy. These findings also support the aggressive approach to resection of tumor-bearing NE regions.

12.
Chaos ; 34(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38572944

RESUMO

We have studied the rich dynamics of a damped particle inside an external double-well potential under the influence of state-dependent time-delayed feedback. In certain regions of the parameter space, we observe multistability with the existence of two different attractors (limit cycle or strange attractor) with well separated mean Lyapunov energies forming a two-level system. Bifurcation analysis reveals that, as the effects of the time-delay feedback are enhanced, chaotic transitions emerge between the two wells of the double-well potential for the attractor corresponding to the fundamental energy level. By computing the residence time distributions and the scaling laws near the onset of chaotic transitions, we rationalize this apparent tunneling-like effect in terms of the crisis-induced intermittency phenomenon. Further, we investigate the first passage times in this regime and observe the appearance of a Cantor-like fractal set in the initial history space, a characteristic feature of hyperbolic chaotic scattering. The non-integer value of the uncertainty dimension indicates that the residence time inside each well is unpredictable. Finally, we demonstrate the robustness of this tunneling intermittency as a function of the memory parameter by calculating the largest Lyapunov exponent.

13.
Mol Cancer Res ; 22(7): 656-667, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38441553

RESUMO

A key feature distinguishing high-grade glioma (HG) from low-grade glioma (LG) is the extensive neovascularization and endothelial hyperproliferation. Prior work has shown that tumor-associated vasculature from HG is molecularly and functionally distinct from normal brain vasculature and expresses higher levels of protumorigenic factors that promote glioma growth and progression. However, it remains unclear whether vessels from LG also express protumorigenic factors, and to what extent they functionally contribute to glioma growth. Here, we profile the transcriptomes of glioma-associated vascular cells (GVC) from IDH-mutant (mIDH) LG and IDH-wild-type (wIDH) HG and show that they exhibit significant molecular and functional differences. LG-GVC show enrichment of extracellular matrix-related gene sets and sensitivity to antiangiogenic drugs, whereas HG-GVC display an increase in immune response-related gene sets and antiangiogenic resistance. Strikingly, conditioned media from LG-GVC inhibits the growth of wIDH glioblastoma cells, whereas HG-GVC promotes growth. In vivo cotransplantation of LG-GVC with tumor cells reduces growth, whereas HG-GVC enhances tumor growth in orthotopic xenografts. We identify ASPORIN (ASPN), a small leucine-rich repeat proteoglycan, highly enriched in LG-GVC as a growth suppressor of wIDH glioblastoma cells in vitro and in vivo. Together, these findings indicate that GVC from LG and HG are molecularly and functionally distinct and differentially regulate tumor growth. Implications: This study demonstrated that vascular cells from IDH-mutant LG and IDH-wild-type HG exhibit distinct molecular signatures and have differential effects on tumor growth via regulation of ASPN-TGFß1-GPM6A signaling.


Assuntos
Neoplasias Encefálicas , Glioma , Neovascularização Patológica , Humanos , Glioma/patologia , Glioma/genética , Glioma/metabolismo , Animais , Camundongos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neovascularização Patológica/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Mutação , Gradação de Tumores
14.
Gene ; 910: 148329, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38431234

RESUMO

DNA methylation is an epigenetic modification that can alter gene expression, and the incidence can vary across developmental stages, inflammatory conditions, and sexes. The effects of viral maternal viral infection and sex on the DNA methylation patterns were studied in the hypothalamus of a pig model of immune activation during development. DNA methylation at single-base resolution in regions of high CpG density was measured on 24 individual hypothalamus samples using reduced representation bisulfite sequencing. Differential over- and under-methylated sites were identified and annotated to proximal genes and corresponding biological processes. A total of 120 sites were differentially methylated (FDR-adjusted p-value < 0.05) between maternal infection or sex groups. Among the 66 sites differentially methylated between groups exposed to inflammatory signals and control, most sites were over-methylated in the challenged group and included sites in the promoter regions of genes SIRT3 and NRBP1. Among the 54 differentially methylated sites between females and males, most sites were over-methylated in females and included sites in the promoter region of genes TNC and EIF4G1. The analysis of the genes proximal to the differentially methylated sites suggested that biological processes potentially impacted include immune response, neuron migration and ensheathment, peptide signaling, adaptive thermogenesis, and tissue development. These results suggest that translational studies should consider that the prolonged effect of maternal infection during gestation may be enacted through epigenetic regulatory mechanisms that may differ between sexes.


Assuntos
Metilação de DNA , Epigênese Genética , Masculino , Feminino , Animais , Suínos , Ilhas de CpG , Epigenômica/métodos , Hipotálamo/metabolismo
15.
Aging Cell ; 23(5): e14108, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38408164

RESUMO

Histones serve as a major carrier of epigenetic information in the form of post-translational modifications which are vital for controlling gene expression, maintaining cell identity, and ensuring proper cellular function. Loss of histones in the aging genome can drastically impact the epigenetic landscape of the cell leading to altered chromatin structure and changes in gene expression profiles. In this study, we investigated the impact of age-related changes on histone levels and histone acetylation in the retinal pigment epithelium (RPE) and retina of mice. We observed a global reduction of histones H1, H2A, H2B, H3, and H4 in aged RPE/choroid but not in the neural retina. Transcriptomic analyses revealed significant downregulation of histones in aged RPE/choroid including crucial elements of the histone locus body (HLB) complex involved in histone pre-mRNA processing. Knockdown of HINFP, a key HLB component, in human RPE cells induced histone loss, senescence, and the upregulation of senescence-associated secretory phenotype (SASP) markers. Replicative senescence and chronological aging in human RPE cells similarly resulted in progressive histone loss and acquisition of the SASP. Immunostaining of human retina sections revealed histone loss in RPE with age. Acetyl-histone profiling in aged mouse RPE/choroid revealed a specific molecular signature with loss of global acetyl-histone levels, including H3K14ac, H3K56ac, and H4K16ac marks. These findings strongly demonstrate histone loss as a unique feature of RPE aging and provide critical insights into the potential mechanisms linking histone dynamics, cellular senescence, and aging.


Assuntos
Envelhecimento , Histonas , Epitélio Pigmentado da Retina , Epitélio Pigmentado da Retina/metabolismo , Histonas/metabolismo , Animais , Acetilação , Camundongos , Envelhecimento/metabolismo , Humanos , Senescência Celular , Camundongos Endogâmicos C57BL
16.
Front Cell Infect Microbiol ; 14: 1329438, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38362496

RESUMO

Candida albicans SC5314 is the most-often used strain for molecular manipulation of the species. The SC5314 reference genome sequence is the result of considerable effort from many scientists and has advanced research into fungal biology and pathogenesis. Although the resource is highly developed and presented in a phased diploid format, the sequence includes gaps and does not extend to the telomeres on its eight chromosome pairs. Accurate SC5314 genome assembly is complicated by the presence of extensive repeated sequences and considerable allelic length variation at some loci. Advances in genome sequencing technology provide the tools to obtain highly accurate long-read data that span even the most-difficult-to-assemble genome regions. Here, we describe derivation of a PacBio HiFi data set and creation of a collapsed haploid telomere-to-telomere assembly of the SC5314 genome (ASM3268872v1) that revealed previously unknown features of the strain. ASM3268872v1 subtelomeric distances were up to 19 kb larger than in the reference genome and revealed a family of highly conserved DNA helicase-encoding genes at 10 of the 16 chromosome ends. We also describe alignments of individual HiFi reads to deduce accurate diploid sequences for the most notoriously difficult-to-assemble C. albicans genes: the agglutinin-like sequence (ALS) gene family. We provide a tutorial that demonstrates how the HiFi reads can be visualized to explore any region of interest. Availability of the HiFi reads data set and the ASM3268872v1 comparative guide assembly will streamline research efforts because accurate diploid sequences can be derived using simple in silico methods rather than time-consuming laboratory-bench approaches.


Assuntos
Candida albicans , Genoma Fúngico , Candida albicans/genética , Sequência de Bases , Sequências Repetitivas de Ácido Nucleico , Telômero/genética , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala
17.
Antibiotics (Basel) ; 13(2)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38391571

RESUMO

Among carbapenem-resistant Enterobacterales (CRE) are diverse mechanisms, including those that are resistant to meropenem but susceptible to ertapenem, adding further complexity to the clinical landscape. This study investigates the emergence of ertapenem-resistant, meropenem-susceptible (ErMs) Escherichia coli and Klebsiella pneumoniae CRE across five hospitals in San Antonio, Texas, USA, from 2012 to 2018. The majority of the CRE isolates were non-carbapenemase producers (NCP; 54%; 41/76); 56% of all NCP isolates had an ErMs phenotype. Among ErMs strains, E. coli comprised the majority (72%). ErMs strains carrying blaCTX-M had, on average, 9-fold higher copies of blaCTX-M than CP-ErMs strains as well as approximately 4-fold more copies than blaCTX-M-positive but ertapenem- and meropenem-susceptible (EsMs) strains (3.7 vs. 0.9, p < 0.001). Notably, carbapenem hydrolysis was observed to be mediated by strains harboring blaCTX-M with and without a carbapenemase(s). ErMs also carried more mobile genetic elements, particularly IS26 composite transposons, than EsMs (37 vs. 0.2, p < 0.0001). MGE- ISVsa5 was uniquely more abundant in ErMs than either EsMs or ErMr strains, with over 30 more average ISVsa5 counts than both phenotype groups (p < 0.0001). Immunoblot analysis demonstrated the absence of OmpC expression in NCP-ErMs E. coli, with 92% of strains lacking full contig coverage of ompC. Overall, our findings characterize both collaborative and independent efforts between blaCTX-M and OmpC in ErMs strains, indicating the need to reappraise the term "non-carbapenemase (NCP)", particularly for strains highly expressing blaCTX-M. To improve outcomes for CRE-infected patients, future efforts should focus on mechanisms underlying the emerging ErMs subphenotype of CRE strains to develop technologies for its rapid detection and provide targeted therapeutic strategies.

18.
Front Pediatr ; 12: 1221863, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38410770

RESUMO

Bronchopulmonary dysplasia (BPD) is a complex, multifactorial lung disease affecting preterm neonates that can result in long-term pulmonary and non-pulmonary complications. Current therapies mainly focus on symptom management after the development of BPD, indicating a need for innovative approaches to predict and identify neonates who would benefit most from targeted or earlier interventions. Clinical informatics, a subfield of biomedical informatics, is transforming healthcare by integrating computational methods with patient data to improve patient outcomes. The application of clinical informatics to develop and enhance clinical therapies for BPD presents opportunities by leveraging electronic health record data, applying machine learning algorithms, and implementing clinical decision support systems. This review highlights the current barriers and the future potential of clinical informatics in identifying clinically relevant BPD phenotypes and developing clinical decision support tools to improve the management of extremely preterm neonates developing or with established BPD. However, the full potential of clinical informatics in advancing our understanding of BPD with the goal of improving patient outcomes cannot be achieved unless we address current challenges such as data collection, storage, privacy, and inherent data bias.

19.
Neurotherapeutics ; 21(1): e00300, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38241165

RESUMO

Neurodevelopmental disorders (NDs) are neuropsychiatric conditions affecting central nervous system development, characterized by cognitive and behavioural alterations. Inflammation has been recently linked to NDs. Animal models are essential for understanding their pathophysiology and identifying therapeutic targets. Double-hit models can reproduce neurodevelopmental and neuroinflammatory impairments. Sixty-seven newborn rats were assigned to four groups: Control, Maternal deprivation (MD, 24-h-deprivation), Isolation (Iso, 5 weeks), and Maternal deprivation â€‹+ â€‹Isolation (MD â€‹+ â€‹Iso, also known as double-hit). Cognitive dysfunction was assessed using behavioural tests. Inflammasome, MAPKs, and TLRs inflammatory elements expression in the frontal cortex (FC) and hippocampus (HP) was analysed through western blot and qRT-PCR. Oxidative/nitrosative (O/N) evaluation and corticosterone levels were measured in plasma samples. Double-hit group was affected in executive and working memory. Most inflammasomes and TLRs inflammatory responses were increased in FC compared to the control group, whilst MAPKs were downregulated. Conversely, hippocampal inflammasome and inflammatory components were reduced after the double-hit exposure, while MAPKs were elevated. Our findings reveal differential regulation of innate immune system components in FC and HP in the double-hit group. Further investigations on MAPKs are necessary to understand their role in regulating HP neuroinflammatory status, potentially linking our MAPKs results to cognitive impairments through their proliferative and anti-inflammatory activity.


Assuntos
Lobo Frontal , Inflamassomos , Ratos , Animais , Inflamassomos/metabolismo , Lobo Frontal/metabolismo , Anti-Inflamatórios/metabolismo , Sistema Imunitário/metabolismo , Hipocampo/metabolismo
20.
Vet Surg ; 53(2): 357-366, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37463876

RESUMO

OBJECTIVE: To report the use and feasibility of a self-locking resorbable loop device for cryptorchidectomy. STUDY DESIGN: Clinical prospective study. POPULATION: Twenty horses. METHODS: Horses suspected to have an abdominal testicle/s after admission work-up were enrolled. Horses were anesthetized in dorsal recumbency and a standard laparoscopic technique was performed. The looped device was inserted into the abdomen, glided around the testis/cord and tightened. Then, the spermatic cord was transected prior testis removal. Surgical procedure details and remarks, perioperative complications and total surgical time were recorded. Short- (>3 weeks) and long-term (>6 months) follow-ups were obtained by telephone questionnaire. RESULTS: Median total surgical time was 67 min (range: 43-189 min) and significantly shortened after the first four horses. The loop device was easily glided around 13/20 abdominal testes and required more time and technical skills around larger testes (≥3 years). Excellent intraoperative hemostasis was achieved in 17 horses. Three horses demonstrated mild intraoperative bleeding that required retightening, device replacement or adding a second device, respectively. Three horses developed mild postoperative hemoabdomen identified ultrasonographically and were successfully managed medically. Follow-up revealed no significant complications related to the procedure. One horse was euthanized for colic 4 months after surgery and one died of hemolytic shock 17 months postoperatively. CONCLUSION: This device represents another method to perform equine cryptorchidectomy that requires minimal training and laparoscopic expertise but demands knowledge of the device and application to prevent complications. CLINICAL SIGNIFICANCE: Laparoscopic cryptorchidectomy using this device is an alternative technique for horses <3 years.


Assuntos
Criptorquidismo , Doenças dos Cavalos , Laparoscopia , Masculino , Cavalos/cirurgia , Animais , Criptorquidismo/cirurgia , Criptorquidismo/veterinária , Estudos Prospectivos , Doenças dos Cavalos/cirurgia , Orquiectomia/veterinária , Orquiectomia/métodos , Laparoscopia/veterinária , Laparoscopia/métodos
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