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1.
Geriatr Nurs ; 57: 217-223, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38696879

RESUMO

INTRODUCTION: This study aimed to examine baseline risk factors in Alzheimer's Disease (AD) and Vascular dementia (VaD) patients with neuropsychiatry symptoms (NPS), and determine whether specific risk factors differ by subtypes of dementia for AD and VaD patients with NPS. METHODS: A retrospective data analysis was conducted to evaluate similarities and differences in the risk factors for AD and VaD with NPS. The analysis included 2949 patients with VaD and 6341 patients with clinical confirmation of AD and VaD with or without NPS collected between February 2016 and August 2021. The multivariate logistic regression analysis was used to determine the risk factors associated with AD and VaD with NPS, by predicting the increasing odds (odds ratios (ORs) of an association of a specific baseline risk factor with AD or VaD with NPS. The validity of the regression models was tested using a Hosmer-Lemeshow test, while the Receiver Operating Curve (ROC) was used to test the sensitivity of the models. RESULTS: In the adjusted analysis TSH (OR = 1.781, 95 % CI, p = 0.0025) and CHF (OR = 1.620, 95 %, p = 0.016) were associated with VaD with NPS, while a history of emergency department(ED) admission (OR = 0.277, 95 % CI, p = 0.003) likely to be associated with VaD patients without NPS. For AD patients, a history of CVA (OR = 1.395, 95 % CI, p = 0.032) and cancer (OR = 1.485, 95 % CI, p = 0.013) were associated with AD patients with NPS. DISCUSSION: The findings of this study indicate that an abnormal thyroid gland and CHF were linked to VaD patients with behavioral disturbances, while CVA and cancer were linked to AD patients with behavioral disturbances. These findings suggest the need to develop management strategies for the care of patients with AD and VaD with NPS.

2.
Cancer Discov ; 14(4): 620-624, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38571424

RESUMO

SUMMARY: Spatial biology approaches enabled by innovations in imaging biomarker platforms and artificial intelligence-enabled data integration and analysis provide an assessment of patient and disease heterogeneity at ever-increasing resolution. The utility of spatial biology data in accelerating drug programs, however, requires balancing exploratory discovery investigations against scalable and clinically applicable spatial biomarker analysis.


Assuntos
Inteligência Artificial , Multiômica , Humanos , Desenvolvimento de Medicamentos , Biomarcadores
3.
Anat Sci Educ ; 17(2): 263-273, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37772635

RESUMO

Basic science, clinical science, and health system science (HSS) have become three pillars of integration upon which modern, post-Flexner, medical education is now based. Because of this new approach to curricular integration in a clinical presentation curruculum, medical training is now placed in the context of healthcare delivery. This study described the design, implementation, and assessment of an integrated teaching strategy, including the effect on students' performance in a medical neuroscience course's summative and formative examinations of an integrated clinical presentation curriculum. The integrated teaching of basic science content, clinical case discussion, and HSS was performed in the first year of an allopathic integrated pre-clerkship curriculum. The two cohorts were from two different years, spring 2018 and 2019. The acceptance of the integrated teaching strategy by medical students was above 80% in all categories that were assessed, including enhancing the integrated experience in learning basic and clinical science materials in the context of HSS; understanding of the learning lessons; facilitation of self-directed learning; provision of a better learning environment; and a holistic understanding of materials including the relevance of HSS issues in the discussion of neurological cases in the medical career of the students. More than 90% of the students scored ≥70% in summative questions mapped to the four learning objectives of the integrated teaching session. The objectives are the correlation of structure to specific functions (94.0 ± 0.21), clinical anatomical features of the nervous system (95.0 ± 0.27), cross-sectional features of the nervous system (96.0 ± 0.31), and the effect of lesions on the structure and functional pathways of the nervous system (97.0 ± 0.34). This result was significantly higher when compared to students' performance in the non-integrated teaching cohort (p < 0.05). Formative assessments (F(7,159) = 92.52, p < 0.001) were significantly different between the two groups. When medical students were evaluated using the same questions for formative assessment, they performed better in the integrated teaching cohort (*p < 0.05) compared to the non-integrated teaching cohort (**p < 0.05).


Assuntos
Anatomia , Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Estudos Transversais , Anatomia/educação , Currículo , Aprendizagem
4.
Nat Metab ; 5(11): 1870-1886, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37946084

RESUMO

Tumors are intrinsically heterogeneous and it is well established that this directs their evolution, hinders their classification and frustrates therapy1-3. Consequently, spatially resolved omics-level analyses are gaining traction4-9. Despite considerable therapeutic interest, tumor metabolism has been lagging behind this development and there is a paucity of data regarding its spatial organization. To address this shortcoming, we set out to study the local metabolic effects of the oncogene c-MYC, a pleiotropic transcription factor that accumulates with tumor progression and influences metabolism10,11. Through correlative mass spectrometry imaging, we show that pantothenic acid (vitamin B5) associates with MYC-high areas within both human and murine mammary tumors, where its conversion to coenzyme A fuels Krebs cycle activity. Mechanistically, we show that this is accomplished by MYC-mediated upregulation of its multivitamin transporter SLC5A6. Notably, we show that SLC5A6 over-expression alone can induce increased cell growth and a shift toward biosynthesis, whereas conversely, dietary restriction of pantothenic acid leads to a reversal of many MYC-mediated metabolic changes and results in hampered tumor growth. Our work thus establishes the availability of vitamins and cofactors as a potential bottleneck in tumor progression, which can be exploited therapeutically. Overall, we show that a spatial understanding of local metabolism facilitates the identification of clinically relevant, tractable metabolic targets.


Assuntos
Neoplasias da Mama , Humanos , Camundongos , Animais , Feminino , Neoplasias da Mama/metabolismo , Ácido Pantotênico , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição/metabolismo , Vitaminas
5.
Proc Natl Acad Sci U S A ; 120(49): e2312261120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38011568

RESUMO

While radical prostatectomy remains the mainstay of prostate cancer (PCa) treatment, 20 to 40% of patients develop postsurgical biochemical recurrence (BCR). A particularly challenging clinical cohort includes patients with intermediate-risk disease whose risk stratification would benefit from advanced approaches that complement standard-of-care diagnostic tools. Here, we show that imaging tumor lactate using hyperpolarized 13C MRI and spatial metabolomics identifies BCR-positive patients in two prospective intermediate-risk surgical cohorts. Supported by spatially resolved tissue analysis of established glycolytic biomarkers, this study provides the rationale for multicenter trials of tumor metabolic imaging as an auxiliary tool to support PCa treatment decision-making.


Assuntos
Antígeno Prostático Específico , Neoplasias da Próstata , Masculino , Humanos , Antígeno Prostático Específico/análise , Ácido Láctico , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Próstata/patologia , Prostatectomia/métodos , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos
6.
Eur J Hum Genet ; 31(12): 1421-1429, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37704779

RESUMO

Börjeson-Forssman-Lehmann syndrome (BFLS) is an X-linked intellectual disability syndrome caused by variants in the PHF6 gene. We ascertained 19 individuals from 15 families with likely pathogenic or pathogenic PHF6 variants (11 males and 8 females). One family had previously been reported. Six variants were novel. We analysed the clinical and genetic findings in our series and compared them with reported BFLS patients. Affected males had classic features of BFLS including intellectual disability, distinctive facies, large ears, gynaecomastia, hypogonadism and truncal obesity. Carrier female relatives of affected males were unaffected or had only mild symptoms. The phenotype of affected females with de novo variants overlapped with the males but included linear skin hyperpigmentation and a higher frequency of dental, retinal and cortical brain anomalies. Complications observed in our series included keloid scarring, digital fibromas, absent vaginal orifice, neuropathy, umbilical hernias, and talipes. Our analysis highlighted sex-specific differences in PHF6 variant types and locations. Affected males often have missense variants or small in-frame deletions while affected females tend to have truncating variants or large deletions/duplications. Missense variants were found in a minority of affected females and clustered in the highly constrained PHD2 domain of PHF6. We propose recommendations for the evaluation and management of BFLS patients. These results further delineate and extend the genetic and phenotypic spectrum of BFLS.


Assuntos
Hipogonadismo , Deficiência Intelectual , Deficiência Intelectual Ligada ao Cromossomo X , Masculino , Humanos , Feminino , Deficiência Intelectual/genética , Deficiência Intelectual Ligada ao Cromossomo X/genética , Hipogonadismo/genética , Hipogonadismo/complicações , Hipogonadismo/diagnóstico , Obesidade/genética
8.
J Immunother Cancer ; 11(8)2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553182

RESUMO

BACKGROUND: The prognosis for patients with pancreatic ductal adenocarcinoma (PDAC) remains extremely poor. It has been suggested that the adenosine pathway contributes to the ability of PDAC to evade the immune system and hence, its resistance to immuno-oncology therapies (IOT), by generating extracellular adenosine (eAdo). METHODS: Using genetically engineered allograft models of PDAC in syngeneic mice with defined and different immune infiltration and response to IOT and autochthonous tumors in KPC mice we investigated the impact of the adenosine pathway on the PDAC tumor microenvironment (TME). Flow cytometry and imaging mass cytometry (IMC) were used to characterize the subpopulation frequency and spatial distribution of tumor-infiltrating immune cells. Mass spectrometry imaging (MSI) was used to visualize adenosine compartmentalization in the PDAC tumors. RNA sequencing was used to evaluate the influence of the adenosine pathway on the shaping of the immune milieu and correlate our findings to published data sets in human PDAC. RESULTS: We demonstrated high expression of adenosine pathway components in tumor-infiltrating immune cells (particularly myeloid populations) in the murine models. MSI demonstrated that extracellular adenosine distribution is heterogeneous in tumors, with high concentrations in peri-necrotic, hypoxic regions, associated with rich myeloid infiltration, demonstrated using IMC. Protumorigenic M2 macrophages express high levels of the Adora2a receptor; particularly in the IOT resistant model. Blocking the in vivo formation and function of eAdo (Adoi), using a combination of anti-CD73 antibody and an Adora2a inhibitor slowed tumor growth and reduced metastatic burden. Additionally, blocking the adenosine pathway improved the efficacy of combinations of cytotoxic agents or immunotherapy. Adoi remodeled the TME, by reducing the infiltration of M2 macrophages and regulatory T cells. RNA sequencing analysis showed that genes related to immune modulation, hypoxia and tumor stroma were downregulated following Adoi and a specific adenosine signature derived from this is associated with a poorer prognosis in patients with PDAC. CONCLUSIONS: The formation of eAdo promotes the development of the immunosuppressive TME in PDAC, contributing to its resistance to conventional and novel therapies. Therefore, inhibition of the adenosine pathway may represent a strategy to modulate the PDAC immune milieu and improve therapy response in patients with PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Camundongos , Animais , Adenosina , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/patologia , Imunoterapia/métodos , Microambiente Tumoral
9.
NPJ Breast Cancer ; 9(1): 64, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37543694

RESUMO

Combining the selective AKT inhibitor, capivasertib, and SERD, fulvestrant improved PFS in a Phase III clinical trial (CAPItello-291), treating HR+ breast cancer patients following aromatase inhibitors, with or without CDK4/6 inhibitors. However, clinical data suggests CDK4/6 treatment may reduce response to subsequent monotherapy endocrine treatment. To support understanding of trials such as CAPItello-291 and gain insight into this emerging population of patients, we explored how CDK4/6 inhibitor treatment influences ER+ breast tumour cell function and response to fulvestrant and capivasertib after CDK4/6 inhibitor treatment. In RB+, RB- T47D and MCF7 palbociclib-resistant cells ER pathway ER and Greb-1 expression were reduced versus naïve cells. PI3K-AKT pathway activation was also modified in RB+ cells, with capivasertib less effective at reducing pS6 in RB+ cells compared to parental cells. Expression profiling of parental versus palbociclib-resistant cells confirmed capivasertib, fulvestrant and the combination differentially impacted gene expression modulation in resistant cells, with different responses seen in T47D and MCF7 cells. Fulvestrant inhibition of ER-dependent genes was reduced. In resistant cells, the combination was less effective at reducing cell cycle genes, but a consistent reduction in cell fraction in S-phase was observed in naïve and resistant cells. Despite modified signalling responses, both RB+ and RB- resistant cells responded to combination treatment despite some reduction in relative efficacy and was effective in vivo in palbociclib-resistant PDX models. Collectively these findings demonstrate that simultaneous inhibition of AKT and ER signalling can be effective in models representing palbociclib resistance despite changes in pathway dependency.

11.
Nat Metab ; 5(8): 1303-1318, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37580540

RESUMO

The genomic landscape of colorectal cancer (CRC) is shaped by inactivating mutations in tumour suppressors such as APC, and oncogenic mutations such as mutant KRAS. Here we used genetically engineered mouse models, and multimodal mass spectrometry-based metabolomics to study the impact of common genetic drivers of CRC on the metabolic landscape of the intestine. We show that untargeted metabolic profiling can be applied to stratify intestinal tissues according to underlying genetic alterations, and use mass spectrometry imaging to identify tumour, stromal and normal adjacent tissues. By identifying ions that drive variation between normal and transformed tissues, we found dysregulation of the methionine cycle to be a hallmark of APC-deficient CRC. Loss of Apc in the mouse intestine was found to be sufficient to drive expression of one of its enzymes, adenosylhomocysteinase (AHCY), which was also found to be transcriptionally upregulated in human CRC. Targeting of AHCY function impaired growth of APC-deficient organoids in vitro, and prevented the characteristic hyperproliferative/crypt progenitor phenotype driven by acute deletion of Apc in vivo, even in the context of mutant Kras. Finally, pharmacological inhibition of AHCY reduced intestinal tumour burden in ApcMin/+ mice indicating its potential as a metabolic drug target in CRC.


Assuntos
Neoplasias Colorretais , Animais , Humanos , Camundongos , Adenosil-Homocisteinase/genética , Adenosil-Homocisteinase/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Metabolômica , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética
12.
Med Sci Educ ; 33(3): 747-753, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37501810

RESUMO

Purpose: Despite the different benefits of formative assessments in an integrated medical curriculum, the effective strategies to provide feedback to medical students to benefit from the different merits of formative assessment are not fully understood. This study aims to determine the effect of different strategies of formative feedback on students' outcomes in a medical neuroscience course. Method: We compared medical students' performance in summative examinations in the academic year that formative feedback was provided using in-person discussion and compared such performances with the academic year when the feedback was provided by written rationales or a combination of written rationales and in-person discussion. We also surveyed medical students' preferences for whether written or in-person formative feedback is a better strategy to provide feedback at the end of each course. Results: ANOVA found a significant difference in summative performance scores for those scoring ≥ 70% when formative feedback was provided by providing a rationale, in-person, and a combination of both ([F (2,80) = 247.60, P < 0.001]. Post hoc analysis revealed a significant and highest performance when feedback was provided using the written rationale approach (***P < 0.05), followed by in-person (**P < 0.05). In contrast, the least performance was recorded when formative feedback was provided using a combination of providing a written rationale for the answers to the questions and in-person discussion of the questions (*P < 0.05). Students' preferred approach for receiving formative feedback for their formative assessment was highest for written rationale (***P < 0.05), followed by in-person or a combination of in-person and written rationale (**P < 0.05). Conclusion: Our results found that medical students preferred a written formative feedback approach, which was associated with better student performance on the summative examination. This study reveals the importance of developing effective strategies to provide formative feedback to medical students for medical students to fully benefit from the merits of formative assessment in an integrated medical school curriculum.

14.
JMIR Perioper Med ; 6: e40402, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37256676

RESUMO

BACKGROUND: Pelvic organ prolapse (POP) refers to symptomatic descent of the vaginal wall. To reduce surgical failure rates, surgical correction can be augmented with the insertion of polypropylene mesh. This benefit is offset by the risk of mesh complication, predominantly mesh exposure through the vaginal wall. If mesh placement is under consideration as part of prolapse repair, patient selection and counseling would benefit from the prediction of mesh exposure; yet, no such reliable preoperative method currently exists. Past studies indicate that inflammation and associated cytokine release is correlated with mesh complication. While some degree of mesh-induced cytokine response accompanies implantation, excessive or persistent cytokine responses may elicit inflammation and implant rejection. OBJECTIVE: Here, we explore the levels of biomaterial-induced blood cytokines from patients who have undergone POP repair surgery to (1) identify correlations among cytokine expression and (2) predict postsurgical mesh exposure through the vaginal wall. METHODS: Blood samples from 20 female patients who previously underwent surgical intervention with transvaginal placement of polypropylene mesh to correct POP were collected for the study. These included 10 who experienced postsurgical mesh exposure through the vaginal wall and 10 who did not. Blood samples incubated with inflammatory agent lipopolysaccharide, with sterile polypropylene mesh, or alone were analyzed for plasma levels of 13 proinflammatory and anti-inflammatory cytokines using multiplex assay. Data were analyzed by principal component analysis (PCA) to uncover associations among cytokines and identify cytokine patterns that correlate with postsurgical mesh exposure through the vaginal wall. Supervised machine learning models were created to predict the presence or absence of mesh exposure and probe the number of cytokine measurements required for effective predictions. RESULTS: PCA revealed that proinflammatory cytokines interferon gamma, interleukin 12p70, and interleukin 2 are the largest contributors to the variance explained in PC 1, while anti-inflammatory cytokines interleukins 10, 4, and 6 are the largest contributors to the variance explained in PC 2. Additionally, PCA distinguished cytokine correlations that implicate prospective therapies to improve postsurgical outcomes. Among machine learning models trained with all 13 cytokines, the artificial neural network, the highest performing model, predicted POP surgical outcomes with 83% (15/18) accuracy; the same model predicted POP surgical outcomes with 78% (14/18) accuracy when trained with just 7 cytokines, demonstrating retention of predictive capability using a smaller cytokine group. CONCLUSIONS: This preliminary study, incorporating a sample size of just 20 participants, identified correlations among cytokines and demonstrated the potential of this novel approach to predict mesh exposure through the vaginal wall following transvaginal POP repair surgery. Further study with a larger sample size will be pursued to confirm these results. If corroborated, this method could provide a personalized medicine approach to assist surgeons in their recommendation of POP repair surgeries with minimal potential for adverse outcomes.

15.
Int J Mol Sci ; 24(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37047786

RESUMO

The two-hit model has been proposed to explain the effects of diabetes on mothers who are already in a putative subclinical damaged state and then undergo neuronal damage during the delivery process. However, the anatomical and pathophysiological mechanisms are not well understood. Our overarching hypothesis in this review paper is that pregnant women who are diabetic have a damaged peripheral nervous system, constituting the "first hit" hypothesis. The delivery process itself-the "second hit"-can produce neurological damage to the mother. Women with diabetes mellitus (DM) are at risk for neurological damage during both hits, but the cumulative effects of both "hits" pose a greater risk of neurological damage and pathophysiological changes during delivery. In our analysis, we introduce the different steps of our concept paper. Subsequently, we describe each of the topics. First, we outline the mechanisms by which diabetes acts as a detrimental variable in neuropathy by focusing on the most common form of diabetic neuropathy, diabetic distal symmetrical polyneuropathy, also known as distal sensorimotor neuropathy. The possible role of macrosomia in causing diabetic neuropathy and obstetric neurological injury is discussed. Second, we describe how vaginal delivery can cause various obstetrical neurological syndromes and pathophysiological changes. Third, we highlight the risk of obstetric neuropathy and discuss anatomical sites at which lesions may occur, including lesions during delivery. Fourth, we characterize the pathophysiological pathways involved in the causation of diabetic neuropathy. Finally, we highlight diabetic damage to sensory vs. motor nerves, including how hyperglycemia causes different types of damage depending on the location of nerve cell bodies.


Assuntos
Diabetes Mellitus , Neuropatias Diabéticas , Hiperglicemia , Gravidez , Humanos , Feminino , Neuropatias Diabéticas/patologia
16.
Metabolites ; 13(3)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36984817

RESUMO

With increased use of mass spectrometry imaging (MSI) in support of pharmaceutical research and development, there are opportunities to develop analytical pipelines that incorporate exploratory high-performance analysis with higher capacity and faster targeted MSI. Therefore, to enable faster MSI data acquisition we present analyte-targeted desorption electrospray ionization-mass spectrometry imaging (DESI-MSI) utilizing a triple-quadrupole (TQ) mass analyzer. The evaluated platform configuration provided superior sensitivity compared to a conventional time-of-flight (TOF) mass analyzer and thus holds the potential to generate data applicable to pharmaceutical research and development. The platform was successfully operated with sampling rates up to 10 scans/s, comparing positively to the 1 scan/s commonly used on comparable DESI-TOF setups. The higher scan rate enabled investigation of the desorption/ionization processes of endogenous lipid species such as phosphatidylcholines and a co-administered cassette of four orally dosed drugs-erlotininb, moxifloxacin, olanzapine, and terfenadine. This was used to enable understanding of the impact of the desorption/ionization processes in order to optimize the operational parameters, resulting in improved compound coverage for olanzapine and the main olanzapine metabolite, hydroxy-olanzapine, in brain tissue sections compared to DESI-TOF analysis or matrix-assisted laser desorption/ionization (MALDI) platforms. The approach allowed reducing the amount of recorded information, thus reducing the size of datasets from up to 150 GB per experiment down to several hundred MB. The improved performance was demonstrated in case studies investigating the suitability of this approach for mapping drug distribution, spatially resolved profiling of drug-induced nephrotoxicity, and molecular-histological tissue classification of ovarian tumors specimens.

17.
Vaccines (Basel) ; 11(2)2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36851240

RESUMO

The COVID-19 pandemic has led to significant loss of life and severe disability, justifying the expedited testing and approval of messenger RNA (mRNA) vaccines. While found to be safe and effective, there have been increasing reports of myocarditis after COVID-19 mRNA vaccine administration. The acute events have been severe enough to require admission to the intensive care unit in some, but most patients fully recover with only rare deaths reported. The pathways involved in the development of vaccine-associated myocarditis are highly dependent on the specific vaccine. COVID-19 vaccine-associated myocarditis is believed to be primarily caused by uncontrolled cytokine-mediated inflammation with possible genetic components in the interleukin-6 signaling pathway. There is also a potential autoimmune component via molecular mimicry. Many of these pathways are similar to those seen in viral myocarditis, indicating a common pathophysiology. There is concern for residual cardiac fibrosis and increased risk for the development of cardiomyopathies later in life. This is of particular interest for patients with congenital heart defects who are already at increased risk for fibrotic cardiomyopathies. Though the risk for vaccine-associated myocarditis is important to consider, the risk of viral myocarditis and other injury is far greater with COVID-19 infection. Considering these relative risks, it is still recommended that the general public receive vaccination against COVID-19, and it is particularly important for congenital heart defect patients to receive vaccination for COVID-19.

18.
Redox Biol ; 59: 102600, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36630820

RESUMO

Current treatments for acute ischemic stroke aim to reinstate a normal perfusion in the ischemic territory but can also cause significant ischemia-reperfusion (IR) injury. Previous data in experimental models of stroke show that ischemia leads to the accumulation of succinate, and, upon reperfusion, the accumulated succinate is rapidly oxidized by succinate dehydrogenase (SDH) to drive superoxide production at mitochondrial complex I. Despite this process initiating IR injury and causing further tissue damage, the potential of targeting succinate metabolism to minimize IR injury remains unexplored. Using both quantitative and untargeted high-resolution metabolomics, we show a time-dependent accumulation of succinate in both human and mouse brain exposed to ischemia ex vivo. In a mouse model of ischemic stroke/mechanical thrombectomy mass spectrometry imaging (MSI) shows that succinate accumulation is confined to the ischemic region, and that the accumulated succinate is rapidly oxidized upon reperfusion. Targeting succinate oxidation by systemic infusion of the SDH inhibitor malonate upon reperfusion leads to a dose-dependent decrease in acute brain injury. Together these findings support targeting succinate metabolism upon reperfusion to decrease IR injury as a valuable adjunct to mechanical thrombectomy in ischemic stroke.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , AVC Isquêmico , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Camundongos , Animais , Humanos , Isquemia , Traumatismo por Reperfusão/terapia , Traumatismo por Reperfusão/metabolismo , Isquemia Encefálica/terapia , Isquemia Encefálica/metabolismo , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/metabolismo , Ácido Succínico/metabolismo , Trombectomia
19.
Int J Aging Hum Dev ; 96(1): 63-75, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35695199

RESUMO

The Research Education Program (REP) is an NIH R25-funded training grant designed to increase the pipeline of underrepresented minority (URM) students entering graduate programs and pursuing biomedical research and health care careers. Each week, students participated in different academic enrichment activities during morning sessions. Research activities were during afternoon sessions. URM students presented their research findings in a local poster session with their peers, graduate medical students, and faculty members. They also attended national conferences to gain experience and expand their professional networks. Our participants included 14.3% rural, 42.85% suburban, and 42.85% urban students. Of this, 83.33% were females, while 16.67% were males. In addition, 100% of students indicated exceptional satisfaction in 64.0% of the academic enrichment activities offered by the REP, and 100% indicated exceptional satisfaction in 63.0% of the research activities. Future research will investigate the long-term effects of REP and graduate enrollments.


Assuntos
Grupos Minoritários , Estudantes , Masculino , Feminino , Humanos , Pesquisa , Percepção , Escolha da Profissão
20.
Nat Commun ; 13(1): 7690, 2022 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-36509758

RESUMO

The brain is a major sanctuary site for metastatic cancer cells that evade systemic therapies. Through pre-clinical pharmacological, biological, and molecular studies, we characterize the functional link between drug resistance and central nervous system (CNS) relapse in Epidermal Growth Factor Receptor- (EGFR-) mutant non-small cell lung cancer, which can progress in the brain when treated with the CNS-penetrant EGFR inhibitor osimertinib. Despite widespread osimertinib distribution in vivo, the brain microvascular tumor microenvironment (TME) is associated with the persistence of malignant cell sub-populations, which are poised to proliferate in the brain as osimertinib-resistant lesions over time. Cellular and molecular features of this poised state are regulated through a Ras homolog family member A (RhoA) and Serum Responsive Factor (SRF) gene expression program. RhoA potentiates the outgrowth of disseminated tumor cells on osimertinib treatment, preferentially in response to extracellular laminin and in the brain. Thus, we identify pre-existing and adaptive features of metastatic and drug-resistant cancer cells, which are enhanced by RhoA/SRF signaling and the brain TME during the evolution of osimertinib-resistant disease.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteína rhoA de Ligação ao GTP/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Receptores ErbB/genética , Compostos de Anilina/farmacologia , Compostos de Anilina/uso terapêutico , Encéfalo/patologia , Mutação , Resistencia a Medicamentos Antineoplásicos/genética , Microambiente Tumoral
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