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1.
Cureus ; 16(5): e60411, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38882970

RESUMO

Baclofen is a commonly prescribed muscle relaxant that functions to reduce spasticity associated with a variety of musculoskeletal and neurological conditions. Patients with decreased renal function, however, are at an increased risk of suffering from baclofen withdrawal symptoms. We discuss the case of a 77-year-old male who presented to the emergency room with altered mental status and was admitted for acute metabolic encephalopathy found to be from abrupt cessation of baclofen. The presence of kidney disease in this patient further increased his susceptibility to the withdrawal symptoms that began after cessation of the normal medication regimen. This case further illustrates the importance of both comprehensive history and a high index of suspicion when it comes to patient presentation of baclofen withdrawal.

2.
Anat Sci Int ; 99(3): 305-319, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38758496

RESUMO

Variations in the arch of the aorta and aortic valves among fetal, cadaveric, and post-mortem specimens present a spectrum of anatomical configurations, posing challenges in establishing a standard norm. While some variations hold surgical significance, many bear little functional consequence but provide insights into embryological origins. The aortic arch exhibits diverse branching patterns, including common trunks and different orders, relevant for endovascular surgeries. Meanwhile, malformations in the aortic valve, affecting the aorta, may lead to ischemia and cerebral infarction, warranting understanding of coexisting arch and valve anomalies to predict complications like aortic dissection. Studies in the Indian population mirror global variations, underscoring the need to explore embryological, clinical, and surgical implications for safer vascular surgeries involving the aortic arch and valves. The study's objectives included examining branching patterns, diameters, and distances between arch branches and exploring aortic valve variations. Employing a cross-sectional design, the study was conducted across Anatomy, Forensic Medicine, and Obstetrics and Gynecology departments. A sample of 100, comprising cadavers, fetuses, and postmortem specimens, were gathered. Specimens ranged from 14 weeks of intrauterine life to 85 years, with intact thoracic cages as inclusion criteria. Methodology involved dissection, specimen fixation, and macroscopic examination for variations and morphological parameters. Results showed aortic diameter increase with age, with significant gender differences. A statistically significant association between arch variations and anomalous valves was observed, suggesting mutual predictability. Individuals with valve anomalies should undergo comprehensive cardiology evaluation to avert complications like aortic dissection during endovascular surgeries. While atheromatous plaques were prevalent in younger groups, their frequency rose with age, necessitating vigilant vascular monitoring. Careful handling during surgeries is paramount, given potential adverse outcomes resulting from variations. Overall, the study underscores the importance of comprehensive anatomical understanding in clinical contexts, guiding effective management strategies and ensuring patient safety in vascular surgeries.


Assuntos
Variação Anatômica , Aorta Torácica , Valva Aórtica , Cadáver , Humanos , Feminino , Masculino , Valva Aórtica/anatomia & histologia , Valva Aórtica/anormalidades , Aorta Torácica/anatomia & histologia , Aorta Torácica/embriologia , Idoso , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Adolescente , Adulto Jovem , Criança , Lactente , Pré-Escolar , Feto/anatomia & histologia , Recém-Nascido , Estudos Transversais
3.
J Cannabis Res ; 6(1): 18, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582889

RESUMO

BACKGROUND: Prior reports indicate that modulation of the endocannabinoid system (ECS) may have a protective benefit for Covid-19 patients. However, associations between cannabis use (CU) or CU not in remission (active cannabis use (ACU)), and Covid-19-related outcomes among hospitalized patients is unknown. METHODS: In this multicenter retrospective observational cohort analysis of adults (≥ 18 years-old) identified from 2020 National Inpatient Sample database, we utilize multivariable regression analyses and propensity score matching analysis (PSM) to analyze trends and outcomes among Covid-19-related hospitalizations with CU and without CU (N-CU) for primary outcome of interest: Covid-19-related mortality; and secondary outcomes: Covid-19-related hospitalization, mechanical ventilation (MV), and acute pulmonary embolism (PE) compared to all-cause admissions; for CU vs N-CU; and for ACU vs N-ACU. RESULTS: There were 1,698,560 Covid-19-related hospitalizations which were associated with higher mortality (13.44% vs 2.53%, p ≤ 0.001) and worse secondary outcomes generally. Among all-cause hospitalizations, 1.56% of CU and 6.29% of N-CU were hospitalized with Covid-19 (p ≤ 0.001). ACU was associated with lower odds of MV, PE, and death among the Covid-19 population. On PSM, ACU(N(unweighted) = 2,382) was associated with 83.97% lower odds of death compared to others(N(unweighted) = 282,085) (2.77% vs 3.95%, respectively; aOR:0.16, [0.10-0.25], p ≤ 0.001). CONCLUSIONS: These findings suggest that the ECS may represent a viable target for modulation of Covid-19. Additional studies are needed to further explore these findings.

4.
Nat Commun ; 15(1): 3602, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684700

RESUMO

Glioblastoma (GBM) is a highly lethal type of cancer. GBM recurrence following chemoradiation is typically attributed to the regrowth of invasive and resistant cells. Therefore, there is a pressing need to gain a deeper understanding of the mechanisms underlying GBM resistance to chemoradiation and its ability to infiltrate. Using a combination of transcriptomic, proteomic, and phosphoproteomic analyses, longitudinal imaging, organotypic cultures, functional assays, animal studies, and clinical data analyses, we demonstrate that chemoradiation and brain vasculature induce cell transition to a functional state named VC-Resist (vessel co-opting and resistant cell state). This cell state is midway along the transcriptomic axis between proneural and mesenchymal GBM cells and is closer to the AC/MES1-like state. VC-Resist GBM cells are highly vessel co-opting, allowing significant infiltration into the surrounding brain tissue and homing to the perivascular niche, which in turn induces even more VC-Resist transition. The molecular and functional characteristics of this FGFR1-YAP1-dependent GBM cell state, including resistance to DNA damage, enrichment in the G2M phase, and induction of senescence/stemness pathways, contribute to its enhanced resistance to chemoradiation. These findings demonstrate how vessel co-option, perivascular niche, and GBM cell plasticity jointly drive resistance to therapy during GBM recurrence.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioblastoma/metabolismo , Glioblastoma/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Animais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Camundongos , Quimiorradioterapia/métodos , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Tolerância a Radiação , Proteínas de Sinalização YAP/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Proteômica
5.
J Am Heart Assoc ; 12(24): e030042, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38108253

RESUMO

The United States witnessed a nearly 4-fold increase in personal health care expenditures between 1980 and 2010. Despite innovations and obvious benefits to health, participants enrolled in clinical trials still do not accurately represent the racial and ethnic composition of patients nationally or globally. This lack of diversity in cohorts limits the generalizability and significance of results among all populations and has deep repercussions for patient equity. To advance diversity in clinical trials, robust evidence for the most effective strategies for recruitment of diverse participants is needed. A major limitation of previous literature on clinical trial diversity is the lack of control or comparator groups for different strategies. To date, interventions have focused primarily on (1) community-based interventions, (2) institutional practices, and (3) digital health systems. This review article outlines prior intervention strategies across these 3 categories and considers health policy and ethical incentives for substantiation before US Food and Drug Administration approval. There are no current studies that comprehensively compare these interventions against one another. The American Heart Association Strategically Focused Research Network on the Science of Diversity in Clinical Trials represents a multicenter, collaborative network between Stanford School of Medicine and Morehouse School of Medicine created to understand the barriers to diversity in clinical trials by contemporaneous head-to-head interventional strategies accessing digital, institutional, and community-based recruitment strategies to produce informed recruitment strategies targeted to improve underrepresented patient representation in clinical trials.


Assuntos
American Heart Association , Instalações de Saúde , Estados Unidos , Humanos , Política de Saúde , Assistência Médica , Diversidade Cultural , Estudos Multicêntricos como Assunto
6.
Nat Commun ; 14(1): 7432, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37973846

RESUMO

Spatial resolution of the T cell repertoire is essential for deciphering cancer-associated immune dysfunction. Current spatially resolved transcriptomic technologies are unable to directly annotate T cell receptors (TCR). We present spatially resolved T cell receptor sequencing (SPTCR-seq), which integrates optimized target enrichment and long-read sequencing for highly sensitive TCR sequencing. The SPTCR computational pipeline achieves yield and coverage per TCR comparable to alternative single-cell TCR technologies. Our comparison of PCR-based and SPTCR-seq methods underscores SPTCR-seq's superior ability to reconstruct the entire TCR architecture, including V, D, J regions and the complementarity-determining region 3 (CDR3). Employing SPTCR-seq, we assess local T cell diversity and clonal expansion across spatially discrete niches. Exploration of the reciprocal interaction of the tumor microenvironmental and T cells discloses the critical involvement of NK and B cells in T cell exhaustion. Integrating spatially resolved omics and TCR sequencing provides as a robust tool for exploring T cell dysfunction in cancers and beyond.


Assuntos
Receptores de Antígenos de Linfócitos T , Linfócitos T , Receptores de Antígenos de Linfócitos T/genética , Regiões Determinantes de Complementaridade/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Perfilação da Expressão Gênica , Receptores de Antígenos de Linfócitos T alfa-beta/genética
8.
Obes Surg ; 33(11): 3472-3486, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37804470

RESUMO

PURPOSE: The association between bariatric surgery and IBD-related inpatient outcomes is not well characterized. We report, analyze, and compare inpatient trends and outcomes among encounters with a history of bariatric surgery (Hx-MBS) compared to those receiving bariatric surgery during index admission (PR-MBS) admitted from 2009 to 2020. METHODS: Retrospective cohort design: the 2009-2020 National Inpatient Sample (NIS) databases were used to identify hospital encounters with patients aged ≥ 18 years with a history of MBS (Hx-MBS) or with procedure coding indicating MBS procedure (PR-MBS) according to International Classification of Diseases, Ninth (ICD-9-CM/ ICD-9-PCS) or Tenth Revision (ICD-10-CM/ICD-10-PCS) Clinical Modification/Procedure Coding System during index admission (ICD-9-CM: V4586; ICD-10-CM: Z9884; ICD-9-PR: 4382, 4389; ICD-10-PR: 0DB64Z3, 0DB63ZZ). Pearson χ2 analysis, analysis of variance, multivariable regression analyses, and propensity matching on independent variables were conducted to analyze significant associations between variables and for primary outcome inflammatory bowel disease-related admission, and secondary outcomes: diagnosis of nonalcoholic steatohepatitis, nonalcoholic fatty liver disease, or chronic mesenteric ischemia during admission. RESULTS: We identified 3,365,784 (76.20%) Hx-MBS hospitalizations and 1,050,900 hospitalizations with PR-MBS (23.80%). Propensity score matching analysis demonstrated significantly higher odds of inflammatory bowel disease, and chronic mesenteric ischemia for Hx-MBS compared to PR-MBS, and significantly lower odds of nonalcoholic steatohepatitis and nonalcoholic fatty liver disease for Hx-MBS compared to PR-MBS. CONCLUSION: In our study, Hx-MBS was associated with significantly increased odds of inflammatory bowel disease and other GI pathologies compared to matched controls. The mechanism by which this occurs is unclear. Additional studies are needed to examine these findings.


Assuntos
Cirurgia Bariátrica , Doenças Inflamatórias Intestinais , Isquemia Mesentérica , Hepatopatia Gordurosa não Alcoólica , Obesidade Mórbida , Humanos , Estudos Retrospectivos , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/cirurgia , Hepatopatia Gordurosa não Alcoólica/complicações , Obesidade Mórbida/cirurgia , Doenças Inflamatórias Intestinais/epidemiologia , Doenças Inflamatórias Intestinais/cirurgia , Doenças Inflamatórias Intestinais/complicações , Cirurgia Bariátrica/métodos , Gastrectomia
9.
STAR Protoc ; 4(3): 102383, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37393609

RESUMO

Single-cell RNA-sequencing (scRNA-seq) is becoming a ubiquitous method in profiling the cellular transcriptomes of both malignant and non-malignant cells from the human brain. Here, we present a protocol to isolate viable tumor cells from human ex vivo glioblastoma cultures for single-cell transcriptomic analysis. We describe steps including surgical tissue collection, sectioning, culturing, primary tumor cells inoculation, growth tracking, fluorescence-based cell sorting, and population-enriched scRNA-seq. This comprehensive methodology empowers in-depth understanding of brain tumor biology at the single-cell level. For complete details on the use and execution of this protocol, please refer to Ravi et al.1.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/genética , Perfilação da Expressão Gênica , Neoplasias Encefálicas/genética , Encéfalo , Transcriptoma/genética
10.
Neuro Oncol ; 25(11): 1963-1975, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37288604

RESUMO

BACKGROUND: In glioblastoma (GBM), the effects of altered glycocalyx are largely unexplored. The terminal moiety of cell coating glycans, sialic acid, is of paramount importance for cell-cell contacts. However, sialic acid turnover in gliomas and its impact on tumor networks remain unknown. METHODS: We streamlined an experimental setup using organotypic human brain slice cultures as a framework for exploring brain glycobiology, including metabolic labeling of sialic acid moieties and quantification of glycocalyx changes. By live, 2-photon and high-resolution microscopy we have examined morphological and functional effects of altered sialic acid metabolism in GBM. By calcium imaging we investigated the effects of the altered glycocalyx on a functional level of GBM networks. RESULTS: The visualization and quantitative analysis of newly synthesized sialic acids revealed a high rate of de novo sialylation in GBM cells. Sialyltrasferases and sialidases were highly expressed in GBM, indicating that significant turnover of sialic acids is involved in GBM pathology. Inhibition of either sialic acid biosynthesis or desialylation affected the pattern of tumor growth and lead to the alterations in the connectivity of glioblastoma cells network. CONCLUSIONS: Our results indicate that sialic acid is essential for the establishment of GBM tumor and its cellular network. They highlight the importance of sialic acid for glioblastoma pathology and suggest that dynamics of sialylation have the potential to be targeted therapeutically.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/patologia , Ácido N-Acetilneuramínico/metabolismo , Ácidos Siálicos/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral
11.
EMBO Mol Med ; 14(12): e15343, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36278433

RESUMO

Lactate is a central metabolite in brain physiology but also contributes to tumor development. Glioblastoma (GB) is the most common and malignant primary brain tumor in adults, recognized by angiogenic and invasive growth, in addition to its altered metabolism. We show herein that lactate fuels GB anaplerosis by replenishing the tricarboxylic acid (TCA) cycle in absence of glucose. Lactate dehydrogenases (LDHA and LDHB), which we found spatially expressed in GB tissues, catalyze the interconversion of pyruvate and lactate. However, ablation of both LDH isoforms, but not only one, led to a reduction in tumor growth and an increase in mouse survival. Comparative transcriptomics and metabolomics revealed metabolic rewiring involving high oxidative phosphorylation (OXPHOS) in the LDHA/B KO group which sensitized tumors to cranial irradiation, thus improving mouse survival. When mice were treated with the antiepileptic drug stiripentol, which targets LDH activity, tumor growth decreased. Our findings unveil the complex metabolic network in which both LDHA and LDHB are integrated and show that the combined inhibition of LDHA and LDHB strongly sensitizes GB to therapy.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Lactato Desidrogenases , Animais , Camundongos , Ácido Láctico , Metabolômica , Glioblastoma/enzimologia , Glioblastoma/patologia , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/patologia
12.
PLoS Pathog ; 18(8): e1010726, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36044447

RESUMO

Although combination antiretroviral therapy (ART) blocks HIV replication, it is not curative because infected CD4+ T cells that carry intact, infectious proviruses persist. Understanding the behavior of clones of infected T cells is important for understanding the stability of the reservoir; however, the stabilities of clones of infected T cells in persons on long-term ART are not well defined. We determined the relative stabilities of clones of infected and uninfected CD4+ T cells over time intervals of one to four years in three individuals who had been on ART for 9-19 years. The largest clones of uninfected T cells were larger than the largest clones of infected T cells. Clones of infected CD4+ T cells were more stable than clones of uninfected CD4+ T cells of a similar size. Individual clones of CD4+ T cells carrying intact, infectious proviruses can expand, contract, or remain stable over time.


Assuntos
Infecções por HIV , HIV-1 , Linfócitos T CD4-Positivos , Células Clonais , DNA Viral , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Provírus/genética
13.
J Virol ; 96(13): e0012222, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35674431

RESUMO

Effective strategies to eliminate human immunodeficiency virus type 1 (HIV-1) reservoirs are likely to require more thorough characterizations of proviruses that persist on antiretroviral therapy (ART). The rarity of infected CD4+ T-cells and related technical challenges have limited the characterization of integrated proviruses. Current approaches using next-generation sequencing can be inefficient and limited sequencing depth can make it difficult to link proviral sequences to their respective integration sites. Here, we report on an efficient method by which HIV-1 proviruses and their sites of integration are amplified and sequenced. Across five HIV-1-positive individuals on clinically effective ART, a median of 41.2% (n = 88 of 209) of amplifications yielded near-full-length proviruses and their 5'-host-virus junctions containing a median of 430 bp (range, 18 to 1,363 bp) of flanking host sequence. Unexpectedly, 29.5% (n = 26 of 88) of the sequenced proviruses had structural asymmetries between the 5' and 3' long terminal repeats (LTRs), commonly in the form of major 3' deletions. Sequence-intact proviruses were detected in 3 of 5 donors, and infected CD4+ T-cell clones were detected in 4 of 5 donors. The accuracy of the method was validated by amplifying and sequencing full-length proviruses and flanking host sequences directly from peripheral blood mononuclear cell DNA. The individual proviral sequencing assay (IPSA) described here can provide an accurate, in-depth, and longitudinal characterization of HIV-1 proviruses that persist on ART, which is important for targeting proviruses for elimination and assessing the impact of interventions designed to eradicate HIV-1. IMPORTANCE The integration of human immunodeficiency virus type 1 (HIV-1) into chromosomal DNA establishes the long-term persistence of HIV-1 as proviruses despite effective antiretroviral therapy (ART). Characterizing proviruses is difficult because of their rarity in individuals on long-term suppressive ART, their highly polymorphic sequences and genetic structures, and the need for efficient amplification and sequencing of the provirus and its integration site. Here, we describe a novel, integrated, two-step method (individual proviral sequencing assay [IPSA]) that amplifies the host-virus junction and the full-length provirus except for the last 69 bp of the 3' long terminal repeat (LTR). Using this method, we identified the integration sites of proviruses, including those that are sequence intact and replication competent or defective. Importantly, this new method identified previously unreported asymmetries between LTRs that have implications for how proviruses are detected and quantified. The IPSA method reported is unaffected by LTR asymmetries, permitting a more accurate and comprehensive characterization of the proviral landscape.


Assuntos
HIV-1 , Provírus , Sequências Repetidas Terminais , Infecções por HIV/virologia , HIV-1/genética , HIV-1/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Leucócitos Mononucleares/virologia , Provírus/genética , Provírus/metabolismo , Sequências Repetidas Terminais/genética
14.
Cancer Cell ; 40(6): 639-655.e13, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35700707

RESUMO

Glioblastomas are malignant tumors of the central nervous system hallmarked by subclonal diversity and dynamic adaptation amid developmental hierarchies. The source of dynamic reorganization within the spatial context of these tumors remains elusive. Here, we characterized glioblastomas by spatially resolved transcriptomics, metabolomics, and proteomics. By deciphering regionally shared transcriptional programs across patients, we infer that glioblastoma is organized by spatial segregation of lineage states and adapts to inflammatory and/or metabolic stimuli, reminiscent of the reactive transformation in mature astrocytes. Integration of metabolic imaging and imaging mass cytometry uncovered locoregional tumor-host interdependence, resulting in spatially exclusive adaptive transcriptional programs. Inferring copy-number alterations emphasizes a spatially cohesive organization of subclones associated with reactive transcriptional programs, confirming that environmental stress gives rise to selection pressure. A model of glioblastoma stem cells implanted into human and rodent neocortical tissue mimicking various environments confirmed that transcriptional states originate from dynamic adaptation to various environments.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Humanos , Metabolômica/métodos
15.
Nat Commun ; 13(1): 925, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177622

RESUMO

Despite recent advances in cancer immunotherapy, certain tumor types, such as Glioblastomas, are highly resistant due to their tumor microenvironment disabling the anti-tumor immune response. Here we show, by applying an in-silico multidimensional model integrating spatially resolved and single-cell gene expression data of 45,615 immune cells from 12 tumor samples, that a subset of Interleukin-10-releasing HMOX1+ myeloid cells, spatially localizing to mesenchymal-like tumor regions, drive T-cell exhaustion and thus contribute to the immunosuppressive tumor microenvironment. These findings are validated using a human ex-vivo neocortical glioblastoma model inoculated with patient derived peripheral T-cells to simulate the immune compartment. This model recapitulates the dysfunctional transformation of tumor infiltrating T-cells. Inhibition of the JAK/STAT pathway rescues T-cell functionality both in our model and in-vivo, providing further evidence of IL-10 release being an important driving force of tumor immune escape. Our results thus show that integrative modelling of single cell and spatial transcriptomics data is a valuable tool to interrogate the tumor immune microenvironment and might contribute to the development of successful immunotherapies.


Assuntos
Neoplasias Encefálicas/imunologia , Glioblastoma/imunologia , Interleucina-10/metabolismo , Células Mieloides/metabolismo , Linfócitos T/imunologia , Adulto , Idoso , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Comunicação Celular/imunologia , Linhagem Celular Tumoral , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Voluntários Saudáveis , Heme Oxigenase-1/metabolismo , Humanos , Imunoterapia/métodos , Inibidores de Janus Quinases/farmacologia , Inibidores de Janus Quinases/uso terapêutico , Janus Quinases/antagonistas & inibidores , Janus Quinases/metabolismo , Masculino , Pessoa de Meia-Idade , Neocórtex/citologia , Neocórtex/imunologia , Neocórtex/patologia , Cultura Primária de Células , RNA-Seq , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Análise de Célula Única , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Técnicas de Cultura de Tecidos , Evasão Tumoral , Microambiente Tumoral/imunologia
16.
Nat Neurosci ; 25(1): 20-25, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34811521

RESUMO

Microglia appear activated in the vicinity of amyloid beta (Aß) plaques, but whether microglia contribute to Aß propagation into unaffected brain regions remains unknown. Using transplantation of wild-type (WT) neurons, we show that Aß enters WT grafts, and that this is accompanied by microglia infiltration. Manipulation of microglia function reduced Aß deposition within grafts. Furthermore, in vivo imaging identified microglia as carriers of Aß pathology in previously unaffected tissue. Our data thus argue for a hitherto unexplored mechanism of Aß propagation.


Assuntos
Peptídeos beta-Amiloides , Microglia , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Humanos , Microglia/metabolismo , Neurônios/metabolismo , Placa Amiloide/patologia
17.
Biomaterials ; 279: 121230, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34736153

RESUMO

Long term implantation of (micro-)probes into neural tissue causes unique and disruptive responses. In this study, we investigate the transcriptional trajectory of glial cells responding to chronic implantation of 380 µm flexible micro-probes for up to 18 weeks. Transcriptomic analysis shows a rapid activation of microglial cells and a strong reactive astrocytic polarization, both of which are lost over the chronic of the implant duration. Animals that were implanted for 18 weeks show a transcriptional profile similar to non-implanted controls, with increased expression of genes associated with wound healing and angiogenesis, which raises hope of a normalization of the neuropil to the pre-injury state when using flexible probes. Nevertheless, our data shows that a subset of genes upregulated after 18 weeks belong to the family of immediate early genes, which indicates that structural and functional remodeling is not complete at this time point. Our results confirm and extend previous work on the molecular changes resulting from the presence of neural probes and provide a rational basis for developing interventional strategies to control them.


Assuntos
Microglia , Neuroglia , Animais , Astrócitos , Eletrodos Implantados , Ratos , Ratos Sprague-Dawley
18.
Sci Adv ; 7(42): eabi8795, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34644108

RESUMO

Retroviruses cause cancers in animals by integrating in or near oncogenes. Although HIV-1 infection increases the risk of cancer, most of the risk is associated with immunodeficiency and coinfection by oncogenic virus (Epstein-Barr virus, Kaposi sarcoma herpesvirus, and human papillomavirus). HIV-1 proviruses integrated in some oncogenes cause clonal expansion of infected T cells in vivo; however, the infected cells are not transformed, and it is generally believed that HIV-1 does not cause cancer directly. We show that HIV-1 proviruses integrated in the first introns of signal transducer and activator of transcription 3 (STAT3) and lymphocyte-specific protein tyrosine kinase (LCK) can play an important role in the development of T cell lymphomas. The development of these cancers appears to be a multistep process involving additional nonviral mutations, which could help explain why T cell lymphomas are rare in persons with HIV-1 infection.

19.
Cell Death Dis ; 12(8): 723, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34290229

RESUMO

Glioblastoma (GBM), the most malignant tumor of the central nervous system, is marked by its dynamic response to microenvironmental niches. In particular, this cellular plasticity contributes to the development of an immediate resistance during tumor treatment. Novel insights into the developmental trajectory exhibited by GBM show a strong capability to respond to its microenvironment by clonal selection of specific phenotypes. Using the same mechanisms, malignant GBM do develop intrinsic mechanisms to resist chemotherapeutic treatments. This resistance was reported to be sustained by the paracrine and autocrine glutamate signaling via ionotropic and metabotropic receptors. However, the extent to which glutamatergic signaling modulates the chemoresistance and transcriptional profile of the GBM remains unexplored. In this study we aimed to map the manifold effects of glutamate signaling in GBM as the basis to further discover the regulatory role and interactions of specific receptors, within the GBM microenvironment. Our work provides insights into glutamate release dynamics, representing its importance for GBM growth, viability, and migration. Based on newly published multi-omic datasets, we explored the and characterized the functions of different ionotropic and metabotropic glutamate receptors, of which the metabotropic receptor 3 (GRM3) is highlighted through its modulatory role in maintaining the ability of GBM cells to evade standard alkylating chemotherapeutics. We addressed the clinical relevance of GRM3 receptor expression in GBM and provide a proof of concept where we manipulate intrinsic mechanisms of chemoresistance, driving GBM towards chemo-sensitization through GRM3 receptor inhibition. Finally, we validated our findings in our novel human organotypic section-based tumor model, where GBM growth and proliferation was significantly reduced when GRM3 inhibition was combined with temozolomide application. Our findings present a new picture of how glutamate signaling via mGluR3 interacts with the phenotypical GBM transcriptional programs in light of recently published GBM cell-state discoveries.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Glioblastoma/tratamento farmacológico , Receptores de Glutamato Metabotrópico/metabolismo , Aminoácidos/farmacologia , Antineoplásicos Alquilantes/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/patologia , Ácido Glutâmico/metabolismo , Humanos , Cinética , Terapia Neoadjuvante , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos , Xantenos/farmacologia
20.
Viruses ; 13(7)2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202310

RESUMO

Efforts to cure HIV-1 infection require better quantification of the HIV-1 reservoir, particularly the clones of cells harboring replication-competent (intact) proviruses, termed repliclones. The digital droplet PCR assays commonly used to quantify intact proviruses do not differentiate among specific repliclones, thus the dynamics of repliclones are not well defined. The major challenge in tracking repliclones is the relative rarity of the cells carrying specific intact proviruses. To date, detection and accurate quantification of repliclones requires in-depth integration site sequencing. Here, we describe a simplified workflow using integration site-specific qPCR (IS-qPCR) to determine the frequencies of the proviruses integrated in individual repliclones. We designed IS-qPCR to determine the frequencies of repliclones and clones of cells that carry defective proviruses in samples from three donors. Comparing the results of IS-qPCR with deep integration site sequencing data showed that the two methods yielded concordant estimates of clone frequencies (r = 0.838). IS-qPCR is a potentially valuable tool that can be applied to multiple samples and cell types over time to measure the dynamics of individual repliclones and the efficacy of treatments designed to eliminate them.


Assuntos
Linfócitos T CD4-Positivos/virologia , Infecções por HIV/virologia , HIV-1/fisiologia , Leucócitos Mononucleares/virologia , Provírus/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Integração Viral , 5'-Nucleotidase/genética , Linhagem Celular , Glicoproteínas/genética , HIV-1/genética , Humanos , Provírus/genética , Carga Viral
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