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1.
Cell ; 185(12): 2184-2199.e16, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35649412

RESUMO

The factors driving therapy resistance in diffuse glioma remain poorly understood. To identify treatment-associated cellular and genetic changes, we analyzed RNA and/or DNA sequencing data from the temporally separated tumor pairs of 304 adult patients with isocitrate dehydrogenase (IDH)-wild-type and IDH-mutant glioma. Tumors recurred in distinct manners that were dependent on IDH mutation status and attributable to changes in histological feature composition, somatic alterations, and microenvironment interactions. Hypermutation and acquired CDKN2A deletions were associated with an increase in proliferating neoplastic cells at recurrence in both glioma subtypes, reflecting active tumor growth. IDH-wild-type tumors were more invasive at recurrence, and their neoplastic cells exhibited increased expression of neuronal signaling programs that reflected a possible role for neuronal interactions in promoting glioma progression. Mesenchymal transition was associated with the presence of a myeloid cell state defined by specific ligand-receptor interactions with neoplastic cells. Collectively, these recurrence-associated phenotypes represent potential targets to alter disease progression.


Assuntos
Neoplasias Encefálicas , Glioma , Microambiente Tumoral , Adulto , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Evolução Molecular , Genes p16 , Glioma/genética , Glioma/patologia , Humanos , Isocitrato Desidrogenase/genética , Mutação , Recidiva Local de Neoplasia
2.
Nature ; 633(8029): 359-364, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38977018

RESUMO

Two-dimensional (2D) and three-dimensional (3D) perovskite heterostructures have played a key role in advancing the performance of perovskite solar cells1,2. However, the migration of cations between 2D and 3D layers results in the disruption of octahedral networks, leading to degradation in performance over time3,4. We hypothesized that perovskitoids, with robust organic-inorganic networks enabled by edge- and face-sharing, could impede ion migration. We explored a set of perovskitoids of varying dimensionality and found that cation migration within perovskitoid-perovskite heterostructures was suppressed compared with the 2D-3D perovskite case. Increasing the dimensionality of perovskitoids improves charge transport when they are interfaced with 3D perovskite surfaces-this is the result of enhanced octahedral connectivity and out-of-plane orientation. The 2D perovskitoid (A6BfP)8Pb7I22 (A6BfP: N-aminohexyl-benz[f]-phthalimide) provides efficient passivation of perovskite surfaces and enables uniform large-area perovskite films. Devices based on perovskitoid-perovskite heterostructures achieve a certified quasi-steady-state power conversion efficiency of 24.6% for centimetre-area perovskite solar cells. We removed the fragile hole transport layers and showed stable operation of the underlying perovskitoid-perovskite heterostructure at 85 °C for 1,250 h for encapsulated large-area devices in ambient air.

3.
Nature ; 598(7880): 348-352, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34552244

RESUMO

The determination of molecular features that mediate clinically aggressive phenotypes in prostate cancer remains a major biological and clinical challenge1,2. Recent advances in interpretability of machine learning models as applied to biomedical problems may enable discovery and prediction in clinical cancer genomics3-5. Here we developed P-NET-a biologically informed deep learning model-to stratify patients with prostate cancer by treatment-resistance state and evaluate molecular drivers of treatment resistance for therapeutic targeting through complete model interpretability. We demonstrate that P-NET can predict cancer state using molecular data with a performance that is superior to other modelling approaches. Moreover, the biological interpretability within P-NET revealed established and novel molecularly altered candidates, such as MDM4 and FGFR1, which were implicated in predicting advanced disease and validated in vitro. Broadly, biologically informed fully interpretable neural networks enable preclinical discovery and clinical prediction in prostate cancer and may have general applicability across cancer types.


Assuntos
Aprendizado Profundo , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/tratamento farmacológico , Proteínas de Ciclo Celular/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Masculino , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptores Androgênicos/genética , Reprodutibilidade dos Testes , Proteína Supressora de Tumor p53/genética
4.
Proc Natl Acad Sci U S A ; 121(27): e2314026121, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38917011

RESUMO

The fucosylation of glycoproteins regulates diverse physiological processes. Inhibitors that can control cellular levels of protein fucosylation have consequently emerged as being of high interest. One area where inhibitors of fucosylation have gained significant attention is in the production of afucosylated antibodies, which exhibit superior antibody-dependent cell cytotoxicity as compared to their fucosylated counterparts. Here, we describe ß-carbafucose, a fucose derivative in which the endocyclic ring oxygen is replaced by a methylene group, and show that it acts as a potent metabolic inhibitor within cells to antagonize protein fucosylation. ß-carbafucose is assimilated by the fucose salvage pathway to form GDP-carbafucose which, due to its being unable to form the oxocarbenium ion-like transition states used by fucosyltransferases, is an incompetent substrate for these enzymes. ß-carbafucose treatment of a CHO cell line used for high-level production of the therapeutic antibody Herceptin leads to dose-dependent reductions in core fucosylation without affecting cell growth or antibody production. Mass spectrometry analyses of the intact antibody and N-glycans show that ß-carbafucose is not incorporated into the antibody N-glycans at detectable levels. We expect that ß-carbafucose will serve as a useful research tool for the community and may find immediate application for the rapid production of afucosylated antibodies for therapeutic purposes.


Assuntos
Cricetulus , Fucose , Fucose/metabolismo , Animais , Células CHO , Glicosilação , Humanos , Trastuzumab/farmacologia , Trastuzumab/metabolismo , Fucosiltransferases/metabolismo , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos
5.
PLoS Pathog ; 20(7): e1012170, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39074144

RESUMO

While Merkel cell polyomavirus (MCPyV or MCV) is an abundant virus frequently shed from healthy skin, it is one of the most lethal tumor viruses in immunocompromised individuals, highlighting the crucial role of host immunity in controlling MCPyV oncogenic potential. Despite its prevalence, very little is known about how MCPyV interfaces with the host immune response to maintain asymptomatic persistent infection and how inadequate control of MCPyV infection triggers MCC tumorigenesis. In this study, we discovered that the MCPyV protein, known as the Alternative Large Tumor Open Reading Frame (ALTO), also referred to as middle T, effectively primes and activates the STING signaling pathway. It recruits Src kinase into the complex of STING downstream kinase TBK1 to trigger its autophosphorylation, which ultimately activates the subsequent antiviral immune response. Combining single-cell analysis with both loss- and gain-of-function studies of MCPyV infection, we demonstrated that the activity of ALTO leads to a decrease in MCPyV replication. Thus, we have identified ALTO as a crucial viral factor that modulates the STING-TBK1 pathway, creating a negative feedback loop that limits viral infection and maintains a delicate balance with the host immune system. Our study reveals a novel mechanism by which a tumorigenic virus-encoded protein can link Src function in cell proliferation to the activation of innate immune signaling, thereby controlling viral spread, and sustaining persistent infection. Our previous findings suggest that STING also functions as a tumor suppressor in MCPyV-driven oncogenesis. This research provides a foundation for investigating how disruptions in the finely tuned virus-host balance, maintained by STING, could alter the fate of MCPyV infection, potentially encouraging malignancy.


Assuntos
Poliomavírus das Células de Merkel , Infecções por Polyomavirus , Proteínas Serina-Treonina Quinases , Infecções Tumorais por Vírus , Proteínas Serina-Treonina Quinases/metabolismo , Infecções por Polyomavirus/metabolismo , Infecções por Polyomavirus/imunologia , Infecções por Polyomavirus/virologia , Humanos , Infecções Tumorais por Vírus/metabolismo , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/virologia , Carcinoma de Célula de Merkel/virologia , Carcinoma de Célula de Merkel/metabolismo , Proteínas de Membrana/metabolismo , Transdução de Sinais , Proteínas Virais/metabolismo , Replicação Viral , Neoplasias Cutâneas/virologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/imunologia , Animais
6.
Nucleic Acids Res ; 52(D1): D351-D359, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37904593

RESUMO

A growing interest in aptamer research, as evidenced by the increase in aptamer publications over the years, has led to calls for a go-to site for aptamer information. A comprehensive, publicly available aptamer dataset, which may be a repository for aptamer data, standardize aptamer reporting, and generate opportunities to expand current research in the field, could meet such a demand. There have been several attempts to create aptamer databases; however, most have been abandoned or removed entirely from public view. Inspired by previous efforts, we have published the UTexas Aptamer Database, https://sites.utexas.edu/aptamerdatabase, which includes a publicly available aptamer dataset and a searchable database containing a subset of all aptamer data collected to date (1990-2022). The dataset contains aptamer sequences, binding and selection information. The information is regularly reviewed internally to ensure accuracy and consistency across all entries. To support the continued curation and review of aptamer sequence information, we have implemented sustaining mechanisms, including researcher training protocols, an aptamer submission form, data stored separately from the database platform, and a growing team of researchers committed to updating the database. Currently, the UTexas Aptamer Database is the largest in terms of the number of aptamer sequences with 1,443 internally reviewed aptamer records.


Assuntos
Aptâmeros de Nucleotídeos , Bases de Dados de Ácidos Nucleicos , Conjuntos de Dados como Assunto
7.
J Am Chem Soc ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39377645

RESUMO

Sialic acid (Neu5Ac) is installed onto glycoconjugates by sialyltransferases (STs) using cytidine monophosphate-Neu5Ac (CMP-ß-d-Neu5Ac) as their donor. The only class of cell-active ST inhibitors are those based on a 3FaxNeu5Ac scaffold, which is metabolically converted into CMP-3FaxNeu5Ac within cells. It is essential for the fluorine to be axial, yet stereoselective installation of fluorine in this specific orientation is challenging. Sialic acid aldolase can convert 3-fluoropyruvate and 2-acetamido-2-deoxy-d-mannopyranose (ManNAc) to 3FNeu5Ac, but stereocontrol of the fluorine in the product has not been possible. We hypothesized that the 3Fax kinetic product of a sialic acid aldolase reaction could be trapped by coupling with CMP-sialic acid synthetase to yield CMP-3FaxNeu5Ac. Here, we report that highly active CMP-sialic acid synthetase and short reaction times produce exclusively CMP-3FaxNeu5Ac. Removal of CMP from CMP-3FaxNeu5Ac under acidic conditions unexpectedly led to 3-fluoro-ß-d-Neu5Ac 2-phosphate (3FaxNeu5Ac-2P). Alkaline phosphatase successfully converted 3FaxNeu5Ac-2P to 3FaxNeu5Ac, enabling stereochemically controlled access to 3FaxNeu5Ac, which is effective in lowering the sialoglycan ligands for Siglecs on cells. Moreover, our kinetic trapping approach could be used to access CMP-3FaxNeu5Ac with modifications at the C5, C9, or both positions, which enabled the chemoenzymatic synthesis of a photo-cross-linkable version of CMP-3FaxNeu5Ac that selectively photo-cross-linked to ST6GAL1 over two other STs.

8.
Br J Cancer ; 131(4): 685-691, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38914804

RESUMO

BACKGROUND: Early phase clinical trials in Oncology represent a subspecialised area where UK patient selection is influenced by access to Experimental Cancer Medicine Centres (ECMCs). Equity of access with respect to social determinants of health (SDoH) were explored for two major ECMCs. METHODS: A retrospective cohort study including all referrals to Newcastle and Manchester ECMCs in 2021 was completed. Consent to screening or pre-screening was stratified against SDoH characteristics, including: Index of Multiple Deprivation (IMD) decile, ethnicity and distance to centre. RESULTS: 1243 patients were referred for trials. IMD quintile 1 (most deprived) patients had reduced likelihood of referral compared to expected population models (OR, 0.67; 95% CI: 0.55 to 0.80, p = <0.0001). IMD quintile 5 (least deprived) had increased likelihood of referral (OR, 1.46; 95% CI: 1.17 to 1.82, p = 0.0007). Living beyond median distance from Manchester reduced the likelihood of consenting to trials (OR, 0.72; 95% CI: 0.55 to 0.94, p = 0.015). Ethnicity data represented a White British propensity. CONCLUSIONS: Inequalities in socioeconomic and geographic factors influence referral and enrolment to early phase clinical trials in Northern England. This has implications for equity of access and generalisability of trial results internationally and warrants further study.


Assuntos
Determinantes Sociais da Saúde , Humanos , Inglaterra/epidemiologia , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/terapia , Idoso , Disparidades em Assistência à Saúde/estatística & dados numéricos , Ensaios Clínicos como Assunto/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos , Seleção de Pacientes , Fatores Socioeconômicos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Adulto
9.
J Virol ; 97(4): e0190722, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36946735

RESUMO

Merkel cell polyomavirus (MCPyV) has been associated with approximately 80% of Merkel cell carcinoma (MCC), an aggressive and increasingly incident skin cancer. The link between host innate immunity, viral load control, and carcinogenesis has been established but poorly characterized. We previously established the importance of the STING and NF-κB pathways in the host innate immune response to viral infection. In this study, we further discovered that MCPyV infection of human dermal fibroblasts (HDFs) induces the expression of type I and III interferons (IFNs), which in turn stimulate robust expression of IFN-stimulated genes (ISGs). Blocking type I IFN downstream signaling using an IFN-ß antibody, JAK inhibitors, and CRISPR knockout of the receptor dramatically repressed MCPyV infection-induced ISG expression but did not significantly restore viral replication activities. These findings suggest that IFN-mediated induction of ISGs in response to MCPyV infection is not crucial to viral control. Instead, we found that type I IFN exerts a more direct effect on MCPyV infection postentry by repressing early viral transcription. We further demonstrated that growth factors normally upregulated in wounded or UV-irradiated human skin can significantly stimulate MCPyV gene expression and replication. Together, these data suggest that in healthy individuals, host antiviral responses, such as IFN production induced by viral activity, may restrict viral propagation to reduce MCPyV burden. Meanwhile, growth factors induced by skin abrasion or UV irradiation may stimulate infected dermal fibroblasts to promote MCPyV propagation. A delicate balance of these mutually antagonizing factors provides a mechanism to support persistent MCPyV infection. IMPORTANCE Merkel cell carcinoma is an aggressive skin cancer that is particularly lethal to immunocompromised individuals. Though rare, MCC incidence has increased significantly in recent years. There are no lasting and effective treatments for metastatic disease, highlighting the need for additional treatment and prevention strategies. By investigating how the host innate immune system interfaces with Merkel cell polyomavirus, the etiological agent of most of these cancers, our studies identified key factors necessary for viral control, as well as conditions that support viral propagation. These studies provide new insights for understanding how the virus balances the effects of the host immune defenses and of growth factor stimulation to achieve persistent infection. Since virus-positive MCC requires the expression of viral oncogenes to survive, our observation that type I IFN can repress viral oncogene transcription indicates that these cytokines could be explored as a viable therapeutic option for treating patients with virus-positive MCC.


Assuntos
Carcinoma de Célula de Merkel , Interferons , Infecções por Polyomavirus , Transdução de Sinais , Infecções Tumorais por Vírus , Poliomavírus das Células de Merkel/imunologia , Interferons/fisiologia , Transdução de Sinais/imunologia , Infecções por Polyomavirus/imunologia , Infecções Tumorais por Vírus/imunologia , Carcinoma de Célula de Merkel/imunologia , Imunidade Inata/imunologia , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Expressão Gênica/imunologia , Replicação Viral/genética
10.
Am J Med Genet A ; : e63871, 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39243170

RESUMO

This research aims to compare and assess the clinical and radiological presentations of tuberous sclerosis complex (TSC)-associated lymphangioleiomyomatosis (LAM) and sporadic LAM. A retrospective medical record review was conducted for 90 patients with confirmed LAM diagnoses. Radiologists who were blinded to the LAM type evaluated CT images of the chest and abdomen for the presence of four CT phenotypes: multiple sclerotic bone lesions (SBLs), multifocal micronodular pneumocyte hyperplasia (MMPH), hepatic fat-containing lesions, and cardiac fat-containing lesions. Statistical analyses were then completed to analyze the differences between TSC-LAM and sporadic LAM. Sporadic LAM patients reported a greater number of clinical symptoms at the time of diagnosis than TSC-LAM patients. All four CT phenotypes were present among the TSC-LAM patient population, whereas hepatic fat containing lesions were the only phenotype present in sporadic LAM patients evaluated in this study. The clinical and radiological presentations of sporadic LAM and TSC-LAM differ significantly, suggesting that the diagnostic criteria for sporadic LAM and/or TSC itself could be adapted accordingly. However, the similarities in the presentation of the LAM types are also important to note as these trends inform theories surrounding the potential underlying pathogenic mechanisms of sporadic LAM.

11.
Horm Behav ; 165: 105618, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39180889

RESUMO

Infusion of 17ß-estradiol (E2) into the dorsal hippocampus (DH) of ovariectomized (OVX) mice enhances memory consolidation, an effect that depends on rapid phosphorylation of extracellular signal-regulated kinase (ERK) and Akt. Astrocytic glutamate transporter 1 (GLT-1) modulates neurotransmission via glutamate uptake from the synaptic cleft. However, little is known about the contribution of DH astrocytes, and astrocytic glutamate transport, to the memory-enhancing effects of E2. This study was designed to test whether DH astrocytes contribute to estrogenic modulation of memory consolidation by determining the extent to which DH GLT-1 is necessary for E2 to enhance memory in object recognition and object placement tasks and trigger rapid phosphorylation events in DH astrocytes. OVX female mice were bilaterally cannulated into the DH or the DH and dorsal third ventricle (ICV). Post-training DH infusion of the GLT-1 inhibitor dihydrokainic acid (DHK) dose-dependently impaired memory consolidation in both tasks. Moreover, the memory-enhancing effects of ICV-infused E2 in each task were blocked by DH DHK infusion. E2 increased p42 ERK and Akt phosphorylation in DH astrocytes, and these effects were blocked by DHK. Results suggest the necessity of DH GLT-1 activity for object and spatial memory consolidation, and for E2 to enhance consolidation of these memories and to rapidly activate cell signaling in DH astrocytes. Findings indicate that astrocytic function in the DH of OVX females is necessary for memory formation and is regulated by E2, and suggest an essential role for DH astrocytic GLT-1 activity in the memory-enhancing effects of E2.


Assuntos
Astrócitos , Estradiol , Transportador 2 de Aminoácido Excitatório , Ácido Glutâmico , Hipocampo , Ovariectomia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Feminino , Estradiol/farmacologia , Camundongos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Ácido Glutâmico/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Consolidação da Memória/efeitos dos fármacos , Consolidação da Memória/fisiologia , Fosforilação/efeitos dos fármacos , Memória/efeitos dos fármacos , Memória/fisiologia , Camundongos Endogâmicos C57BL , Reconhecimento Psicológico/efeitos dos fármacos , Reconhecimento Psicológico/fisiologia , Ácido Caínico/análogos & derivados
12.
J Surg Res ; 302: 106-115, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39094257

RESUMO

INTRODUCTION: Tranexamic acid (TXA) administered early after traumatic brain injury (TBI) can decrease morbidity and mortality. The purpose of this study is to determine if the timing of TXA administration after TBI affects postinjury inflammatory markers or phosphorylated tau (p-tau) levels within the hippocampus. METHODS: Male mice (9-11 wk) were split into six groups based on injury and timing of TXA administration (n = 5 per group): Sham, TBI-only, 100 mg/kg TXA-only, TBI + TXA 10 min, TBI + TXA 1 h, and TBI + TXA 6 h. Moderate concussive TBI was induced via weight drop. Serum and brain homogenates were collected at 6 and 24 h postinjury and analyzed for 14 inflammatory cytokines via multiplex enzyme-linked immunosorbent assay. Serum was analyzed for glial fibrillary acidic protein levels. Additional cohorts were survived to 30 d for hippocampal p-tau quantification using immunohistochemistry. RESULTS: Serum levels of interleukin (IL) 1ß (IL-1ß), IL-3, IL-12, IL-17, monocyte chemoattractant protein-1, granulocyte-macrophage colony-stimulating factor, and regulated on activation, normal T-cell expressed and secreted were elevated in TBI mice compared to sham mice at 24 h. Levels of IL-1ß and monocyte chemoattractant protein-1 were lower in 6-h TXA-treated mice than 1-h TXA-treated mice following TBI. IL-12 and macrophage inflammatory protein-1α levels were decreased in 6-h TXA-treated mice compared to 10-min TXA-treated mice. Administration of TXA at 10 min and 6 h but not 1 h postTBI reduced serum glial fibrillary acidic protein levels compared to TBI-only mice. Hippocampal p-tau accumulation was increased after TBI but not reduced by TXA administration. CONCLUSIONS: Our results demonstrate that neither early nor delayed administration of TXA conveyed significant systemic or cerebral benefit in cytokine levels following TBI. Further research should be conducted to assess blood brain barrier integrity and neurobehavioral recovery following TXA administration postTBI.

13.
J Surg Res ; 300: 25-32, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38795670

RESUMO

INTRODUCTION: Previous literature suggests that sphingolipids may impact systemic coagulation and platelet aggregation, thus modulating the risks of thrombotic events. The goal of this investigation was to evaluate the role of serum sphingolipids on intrinsic platelet function to assess whether pharmacologic manipulation of sphingolipid metabolites would impact platelet aggregability. METHODS: C57BL/6J mice were injected with either normal saline, 1 mg/kg FTY720 (synthetic sphingosine-1-phosphate [S1P] receptor analog), or 5 mg/kg SLM6031434 (sphingosine kinase two inhibitor). Mice were sacrificed at 6 h and whole blood (WB) was collected for impedance aggregometry assessing platelet responsiveness to arachidonic acid or adenosine diphosphate. Ex vivo studies utilized WB or platelet-rich plasma that was pretreated with S1P, FTY720, amitriptyline, or d-sphingosine then analyzed by aggregability and flow cytometry for platelet and platelet-derived microvesicle characteristics. RESULTS: FTY720 and SLM6031434 pretreated induced similar arachidonic acid and adenosine diphosphate-mediated platelet aggregation as controls. Ex vivo WB and platelet-rich plasma treatment with S1P, FTY720, amitriptyline and d-sphingosine did not impact platelet aggregation. The percentages of CD41+, CD62P+ and CD41+/ceramide+, CD62P+/ceramide + platelets, and platelet-derived microvesicle were not significantly different between amitriptyline-treated and normal saline-treated cohorts. CONCLUSIONS: Sphingolipid modulating agents, such as FTY720, SLM6031434, S1P, amitriptyline, ceramide, and d-sphingosine do not appear to independently impact platelet aggregation in murine models.


Assuntos
Plaquetas , Cloridrato de Fingolimode , Camundongos Endogâmicos C57BL , Agregação Plaquetária , Esfingolipídeos , Esfingosina , Animais , Agregação Plaquetária/efeitos dos fármacos , Cloridrato de Fingolimode/farmacologia , Esfingosina/análogos & derivados , Esfingosina/sangue , Camundongos , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Esfingolipídeos/sangue , Esfingolipídeos/metabolismo , Masculino , Lisofosfolipídeos/farmacologia , Lisofosfolipídeos/sangue , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Ácido Araquidônico/farmacologia , Amitriptilina/farmacologia , Difosfato de Adenosina/farmacologia
14.
J Surg Res ; 295: 631-640, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38101109

RESUMO

INTRODUCTION: Dynamic preload assessment measures including pulse pressure variation (PPV), stroke volume variation (SVV), pleth variability index (PVI), and hypotension prediction index (HPI) have been utilized clinically to guide fluid management decisions in critically ill patients. These values aid in the balance of correcting hypotension while avoiding over-resuscitation leading to respiratory failure and increased mortality. However, these measures have not been previously validated at altitude or in those with temporary abdominal closure (TAC). METHODS: Forty-eight female swine (39 ± 2 kg) were separated into eight groups (n = 6) including all combinations of flight versus ground, hemorrhage versus no hemorrhage, and TAC versus no TAC. Flight animals underwent simulated aeromedical evacuation via an altitude chamber at 8000 ft. Hemorrhagic shock was induced via stepwise hemorrhage removing 10% blood volume in 15-min increments to a total blood loss of 40% or a mean arterial pressure of 35 mmHg. Animals were then stepwise transfused with citrated shed blood with 10% volume every 15 min back to full blood volume. PPV, SVV, PVI, and HPI were monitored every 15 min throughout the simulated aeromedical evacuation or ground control. Blood samples were collected and analyzed for serum levels of serum IL-1ß, IL-6, IL-8, and TNF-α. RESULTS: Hemorrhage groups demonstrated significant increases in PPV, SVV, PVI, and HPI at each step compared to nonhemorrhage groups. Flight increased PPV (P = 0.004) and SVV (P = 0.003) in hemorrhaged animals. TAC at ground level increased PPV (P < 0.0001), SVV (P = 0.0003), and PVI (P < 0.0001). When TAC was present during flight, PPV (P = 0.004), SVV (P = 0.003), and PVI (P < 0.0001) values were decreased suggesting a dependent effect between altitude and TAC. There were no significant differences in serum IL-1ß, IL-6, IL-8, or TNF-α concentration between injury groups. CONCLUSIONS: Based on our study, PPV and SVV are increased during flight and in the presence of TAC. Pleth variability index is slightly increased with TAC at ground level. Hypotension prediction index demonstrated no significant changes regardless of altitude or TAC status, however this measure was less reliable once the resuscitation phase was initiated. Pleth variability index may be the most useful predictor of preload during aeromedical evacuation as it is a noninvasive modality.


Assuntos
Hemodinâmica , Hipotensão , Humanos , Feminino , Animais , Suínos , Volume Sistólico , Altitude , Fator de Necrose Tumoral alfa , Interleucina-6 , Interleucina-8 , Pressão Sanguínea , Hemorragia/diagnóstico , Hemorragia/etiologia , Hemorragia/terapia , Hidratação
15.
J Surg Res ; 296: 302-309, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38306935

RESUMO

INTRODUCTION: Grade-C postoperative pancreatic fistulas (POPFs) are dreaded complications following pancreaticoduodenectomy. The aim of this study was to quantify the incidence and risk factors associated with grade C POPF in a national database. METHODS: The National Surgical Quality Improvement Program targeted user files were queried for patients who underwent elective pancreaticoduodenectomy (2014-2020). Outcomes were compared between clinically relevant (CR) grade B POPF and grade C POPF. RESULTS: Twenty-six thousand five hundred fifty-two patients were included, of which 90.1% (n = 23,714) had No CR POPF, 8.7% (n = 2287) suffered grade B POPF, and 1.2% (n = 327) suffered grade C POPF. There was no change in the rate Grade-C fistula overtime (m = 0.06, P = 0.63), while the rate of Grade-B fistula significantly increased (m = +1.40, P < 0.01). Fistula Risk Scores were similar between grade B and C POPFs (high risk: 34.9% versus 31.2%, P = 0.21). Associated morbidity was increased with grade C POPF, including delayed gastric emptying, organ space infections, wound dehiscence, respiratory complications, renal complications, myocardial infarction, and bleeding. On multivariate logistic regression, diabetes mellitus (odds ratio: 1.41 95% confidence interval: 1.06-1.87, P = 0.02) was associated with grade C POPF. CONCLUSIONS: This study represents the largest contemporary series evaluating grade C POPFs. Of those suffering CR POPF, the presence of diabetes mellitus was associated with grade C POPF. While modern management has led to grade C POPF in 1% of cases, they remain associated with alarmingly high morbidity and mortality, requiring further mitigation strategies to improve outcomes.


Assuntos
Diabetes Mellitus , Fístula Pancreática , Humanos , Fístula Pancreática/epidemiologia , Fístula Pancreática/etiologia , Fístula Pancreática/cirurgia , Pâncreas/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Pancreaticoduodenectomia/efeitos adversos , Fatores de Risco , Diabetes Mellitus/etiologia , Estudos Retrospectivos
16.
Curr Oncol Rep ; 26(3): 191-199, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38289521

RESUMO

PURPOSE OF REVIEW: Cancer risk reduction remains a significant concern for both individuals with a cancer diagnosis and those aiming to prevent it. Dairy products, a source of beneficial dietary nutrients, have sparked controversy regarding their impact on cancer risk. RECENT FINDINGS: Evidence indicates that dairy consumption, particularly milk, can decrease colorectal cancer risk. However, cow's milk, a key dairy product, exposes individuals to growth hormones, notably insulin-like growth factor-1, potentially elevating cancer risk. Extensive research supports the link between dairy intake and heightened prostate cancer risk. Nonetheless, investigations into dairy's association with breast, ovarian, and other cancers yield mixed results. The overall data on dairy and cancer remains inconclusive. Available data suggests that a diet emphasizing fiber-rich foods such as whole grains, fruits, and vegetables, while restricting milk and dairy intake-similar to the Mediterranean dietary pattern-might mitigate cancer incidence. However, further research is crucial to elucidate the precise role of dairy products in overall cancer risk.


Assuntos
Leite , Neoplasias , Masculino , Feminino , Animais , Bovinos , Humanos , Neoplasias/epidemiologia , Neoplasias/etiologia , Neoplasias/prevenção & controle , Dieta , Incidência , Padrões Dietéticos
17.
J Cutan Pathol ; 51(9): 658-661, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38769706

RESUMO

Cytophagic histiocytic panniculitis (CHP) is associated with a number of systemic conditions and is characterized by the presence of benign phagocytic histiocytes ("bean bag cells"), including phagocytosed erythrocytes, leukocytes, and platelets. We describe a case of a 72-year-old female who presented with a papular eruption that clinically mimicked pityriasis lichenoides et varioliformis acuta (PLEVA). Given that her skin biopsy had multiple features concerning PLEVA, this diagnosis was classified as a superficial pityriasis lichenoides-like variant of CHP. The histopathologic presence of cytophagic histiocytosis prompted workup for a systemic malignancy, leading to a diagnosis of underlying acute monocytic leukemia of myeloid lineage.


Assuntos
Paniculite , Humanos , Feminino , Idoso , Paniculite/patologia , Paniculite/diagnóstico , Histiócitos/patologia , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/diagnóstico , Leucemia Monocítica Aguda/patologia , Leucemia Monocítica Aguda/diagnóstico , Diagnóstico Diferencial , Diferenciação Celular , Monócitos/patologia
18.
Mol Ther ; 31(7): 1904-1919, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-36945775

RESUMO

The function and significance of RAS proteins in cancer have been widely studied for decades. In 2013, the National Cancer Institute established the RAS Initiative to explore innovative approaches for attacking the proteins encoded by mutant forms of RAS genes and to create effective therapies for RAS-driven cancers. This initiative spurred researchers to develop novel approaches and to discover small molecules targeting this protein that was at one time termed "undruggable." More recently, advanced efforts in RAS degraders including PROTACs, linker-based degraders, and direct proteolysis degraders have been explored as novel strategies to target RAS for cancer treatment. These RAS degraders present new opportunities for RAS therapies and may prove fruitful in understanding basic cell biology. Novel delivery strategies will further enhance the efficacy of these therapeutics. In this review, we summarize recent efforts to develop RAS degraders, including PROTACs and E3 adaptor and ligase fusions as cancer therapies. This review also details the direct RAS protease degrader, RAS/RAP1-specific endopeptidase that directly and specifically cleaves RAS.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Proteólise , Proteínas/metabolismo , Endopeptidases/genética , Proteínas ras/genética , Ubiquitina-Proteína Ligases
19.
Neurol Sci ; 45(2): 507-514, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37736852

RESUMO

Infantile spasms, newly classified as infantile epileptic spasm syndrome (IESS), occur in children under 2 years of age and present as an occur as brief, symmetrical, contractions of the musculature of the neck, trunk, and extremities. When infantile spasms occur with a concomitant hypsarrhythmia on electroencephalogram (EEG) and developmental regression, it is known as West Syndrome. There is no universally accepted mainstay of treatment for this condition, but some options include synthetic adrenocorticotropic hormone (ACTH), repository corticotropin injection (RCI/Acthar Gel), corticosteroids, valproic acid, vigabatrin, and surgery. Without effective treatment, infantile spasms can cause an impairment of psychomotor development and/or cognitive and behavioral functions. The first-line treatment in the USA is ACTH related to high efficacy for cessation of infantile spasms long-term and low-cost profile. Acthar Gel is a repository corticotropin intramuscular injection that became FDA-approved for the treatment of IESS in 2010. Though it is believed that ACTH, Acthar Gel, and corticosteroids all work via a negative feedback pathway to decrease corticotropin-releasing hormone (CRH) release, their safety and efficacy profiles all vary. Vigabatrin and valproic acid are both anti-seizure medications that work by increasing GABA concentrations in the CNS and decreasing excitatory activity. Acthar Gel has been shown to have superior efficacy and a diminished side effect profile when compared with other treatment modalities.


Assuntos
Espasmos Infantis , Criança , Humanos , Lactente , Espasmos Infantis/tratamento farmacológico , Vigabatrina/uso terapêutico , Anticonvulsivantes/uso terapêutico , Ácido Valproico/uso terapêutico , Hormônio Adrenocorticotrópico/uso terapêutico , Hormônio Adrenocorticotrópico/efeitos adversos , Corticosteroides/uso terapêutico , Resultado do Tratamento , Espasmo/tratamento farmacológico , Espasmo/induzido quimicamente , Espasmo/complicações
20.
Mol Cell Neurosci ; 124: 103804, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36592800

RESUMO

Cardiolipin is a mitochondrial phospholipid that is also detected in serum inferring its extracellular release; however, this process has not been directly demonstrated for any of the brain cell types. Nevertheless, extracellular cardiolipin has been shown to modulate several neuroimmune functions of microglia and astrocytes, including upregulation of their endocytic activity. Low cardiolipin levels are associated with brain aging, and may thus hinder uptake of amyloid-ß (Αß) in Alzheimer's disease. We hypothesized that glial cells are one of the sources of extracellular cardiolipin in the brain parenchyma where this phospholipid interacts with neighboring cells to upregulate the endocytosis of Αß. Liquid chromatography-mass spectrophotometry identified 31 different species of cardiolipin released from murine BV-2 microglial cells and revealed this process was accelerated by exposure to Aß42. Extracellular cardiolipin upregulated internalization of fluorescently-labeled Aß42 by primary murine astrocytes, human U118 MG astrocytic cells, and murine BV-2 microglia. Increased endocytic activity in the presence of extracellular cardiolipin was also demonstrated by studying uptake of Aß42 and pHrodo™ Bioparticles™ by human induced pluripotent stem cells (iPSCs)-derived microglia, as well as iPSC-derived human brain organoids containing microglia, astrocytes, oligodendrocytes and neurons. Our observations indicate that Aß42 augments the release of cardiolipin from microglia into the extracellular space, where it can act on microglia and astrocytes to enhance their endocytosis of Aß42. Our observations suggest that the reduced glial uptake of Aß due to the decreased levels of cardiolipin could be at least partially responsible for the extracellular accumulation of Aß in aging and Alzheimer's disease.


Assuntos
Doença de Alzheimer , Células-Tronco Pluripotentes Induzidas , Humanos , Animais , Camundongos , Microglia/metabolismo , Cardiolipinas/metabolismo , Doença de Alzheimer/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Neuroglia/metabolismo , Peptídeos beta-Amiloides/metabolismo , Astrócitos/metabolismo
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