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1.
Proc Natl Acad Sci U S A ; 121(11): e2307813120, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38437570

RESUMO

Lipid nanoparticles (LNPs) largely rely on ionizable lipids to yield successful nucleic acid delivery via electrostatic disruption of the endosomal membrane. Here, we report the identification and evaluation of ionizable lipids containing a thiophene moiety (Thio-lipids). The Thio-lipids can be readily synthesized via the Gewald reaction, allowing for modular lipid design with functional constituents at various positions of the thiophene ring. Through the rational design of ionizable lipid structure, we prepared 47 Thio-lipids and identified some structural criteria required in Thio-lipids for efficient mRNA (messenger RNA) encapsulation and delivery in vitro and in vivo. Notably, none of the tested lipids have a pH-response profile like traditional ionizable lipids, potentially due to the electron delocalization in the thiophene core. Placement of the tails and localization of the ionizable headgroup in the thiophene core can endow the nanoparticles with the capability to reach various tissues. Using high-throughput formulation and barcoding techniques, we optimized the formulations to select two top lipids-20b and 29d-and investigated their biodistribution in mice. Lipid 20b enabled LNPs to transfect the liver and spleen, and 29d LNP transfected the lung and spleen. Unexpectedly, LNP with lipid 20b was especially potent in mRNA delivery to the retina with no acute toxicity, leading to the successful delivery to the photoreceptors and retinal pigment epithelium in non-human primates.


Assuntos
Pulmão , Retina , Animais , Camundongos , Distribuição Tecidual , RNA Mensageiro/genética , Lipídeos
2.
Trends Genet ; 37(1): 73-85, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32988634

RESUMO

Multiple hosts and various life cycle stages prompt the human malaria parasite, Plasmodium falciparum, to acquire sophisticated molecular mechanisms to ensure its survival, spread, and transmission to its next host. To face these environmental challenges, increasing evidence suggests that the parasite has developed complex and complementary layers of regulatory mechanisms controlling gene expression. Here, we discuss the recent developments in the discovery of molecular components that contribute to cell replication and differentiation and highlight the major contributions of epigenetics, transcription factors, and nuclear architecture in controlling gene regulation and life cycle progression in Plasmodium spp.


Assuntos
Cromatina/química , Cromatina/metabolismo , Epigênese Genética , Regulação da Expressão Gênica , Interações Hospedeiro-Parasita , Malária Falciparum/parasitologia , Plasmodium falciparum/genética , Animais , Cromatina/genética , Humanos , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/metabolismo , Fatores de Transcrição
3.
Org Biomol Chem ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946460

RESUMO

The palladium-catalysed regioselective C-H chalcogenation of benzoxazines with disulfides and diselenides in air has been described. In this protocol, palladium acetate serves as the catalyst in conjunction with copper as an oxidizing agent. Through this approach, a wide array of sulfenylation and selenylation reactions of benzomorpholines have been effected, yielding results ranging from good to excellent. Thus, the established procedure demonstrates superb regioselectivity and a strong tolerance towards various functional groups and is suitable for gram-scale synthesis. Additionally, this synthetic approach offers a practical and convenient pathway for late-stage functionalization leading to the Rosenmund-von Braun reaction.

4.
Nano Lett ; 23(12): 5482-5489, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37295781

RESUMO

Current-induced spin-orbit torques (SOTs) enable fast and efficient manipulation of the magnetic state of magnetic tunnel junctions (MTJs), making them attractive for memory, in-memory computing, and logic applications. However, the requirement of the external magnetic field to achieve deterministic switching in perpendicularly magnetized SOT-MTJs limits its implementation for practical applications. Here, we introduce a field-free switching (FFS) solution for the SOT-MTJ device by shaping the SOT channel to create a "bend" in the SOT current. The resulting bend in the charge current creates a spatially nonuniform spin current, which translates into inhomogeneous SOT on an adjacent magnetic free layer enabling deterministic switching. We demonstrate FFS experimentally on scaled SOT-MTJs at nanosecond time scales. This proposed scheme is scalable, material-agnostic, and readily compatible with wafer-scale manufacturing, thus creating a pathway for developing purely current-driven SOT systems.

5.
Acc Chem Res ; 55(1): 2-12, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34850635

RESUMO

Lipid nanoparticles (LNPs) are a type of lipid vesicles that possess a homogeneous lipid core. These vesicles are widely used in small-molecule drug and nucleic acid delivery and recently gained much attention because of their remarkable success as a delivery platform for COVID-19 mRNA vaccines. Nonetheless, the utility of transient protein expression induced by mRNA extends far beyond vaccines against infectious diseases─they also hold promise as cancer vaccines, protein replacement therapies, and gene editing components for rare genetic diseases. However, naked mRNA is inherently unstable and prone to rapid degradation by nucleases and self-hydrolysis. Encapsulation of mRNA within LNPs protects mRNA from extracellular ribonucleases and assists with intracellular mRNA delivery.In this Account, we discuss the core features of LNPs for RNA delivery. We focus our attention on LNPs designed to deliver mRNA; however, we also include examples of siRNA-LNP delivery where appropriate to highlight the commonalities and the dissimilarities due to the nucleic acid structure. First, we introduce the concept of LNPs, the advantages and disadvantages of utilizing nucleic acids as therapeutic agents, and the general reasoning behind the molecular makeup of LNPs. We also briefly highlight the most recent clinical successes of LNP-based nucleic acid therapies. Second, we describe the theory and methods of LNP self-assembly. The common idea behind all of the preparation methods is inducing electrostatic interactions between the nucleic acid and charged lipids and promoting nanoparticle growth via hydrophobic interactions. Third, we break down the LNP composition with special attention to the fundamental properties and purposes of each component. This includes the identified molecular design criteria, commercial sourcing, impact on intracellular trafficking, and contribution to the properties of LNPs. One of the key components of LNPs is ionizable lipids, which initiate electrostatic binding with endosomal membranes and facilitate cytosolic release; however, the roles of other lipid components should not be disregarded, as they are associated with stability, clearance, and distribution of LNPs. Fourth, we review the attributes of LNP constructs as a whole that can heavily influence RNA delivery. These attributes are LNP size, charge, internal structure, lipid packing, lipid membrane hydration, stability, and affinity toward biomacromolecules. We also discuss the specific techniques used to examine these attributes and how they can be adjusted. Finally, we offer our perspective on the future of RNA therapies and some questions that remain in the realm of LNP formulation and optimization.


Assuntos
COVID-19 , Nanopartículas , Humanos , Lipossomos , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , SARS-CoV-2 , Vacinas de mRNA
6.
Clin Exp Rheumatol ; 40(4): 714-719, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35383563

RESUMO

OBJECTIVES: To determine the factors (clinical, biochemical, angiographic, and echocardiographic) which predict left ventricular (LV) dysfunction in Takayasu's arteritis (TAK). TAK causes inflammation of the aorta and its large branches. Systemic hypertension, aortic valvular disease, and coronary artery involvement are probable contributors to LV dysfunction in some patients. In other patients, inflammation and resulting myocarditis play an essential role. However, the prevalence and relative contribution of such predictors of LV dysfunction in TAK patients is unknown. METHODS: We enrolled 87 patients with angiographically confirmed TAK in the study after proper informed consent. A complete clinical, biochemical, and echocardiographic evaluation of all the cases was done. We defined LV systolic dysfunction as an ejection fraction below 50% and diastolic dysfunction by ASE 2016 criteria into grades I, II, and III. RESULTS: We evaluated 87 consecutive angiographically proven TAK patients. The incidence of LV systolic and diastolic dysfunction in our study was 19.5% (17/87) and 100% (87/87), respectively. All the patients with LV dysfunction (n=17, 100%) had an ITAS 2010 score of more than two suggestive of active disease. In 15 (88%) out of 17 patients with LV systolic dysfunction, we could identify a significant haemodynamic cause of LV dysfunction (untreated hypertension HTN, descending thoracic or abdominal aorta stenosis, renal artery stenosis, coronary stenosis, significant valvular regurgitation). In the rest 2 cases, no important haemodynamic factor was present, and here LV dysfunction was probably because of myocarditis and its sequalae. CONCLUSIONS: This study represents the largest cohort of TAK patients to estimate LV systolic and diastolic dysfunction. We have found LV systolic and diastolic dysfunction multifactorial, with hemodynamic and inflammatory factors contributing to its pathophysiology.


Assuntos
Hipertensão , Miocardite , Arterite de Takayasu , Disfunção Ventricular Esquerda , Aorta Abdominal , Constrição Patológica , Humanos , Inflamação , Arterite de Takayasu/complicações , Arterite de Takayasu/diagnóstico por imagem , Arterite de Takayasu/epidemiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/epidemiologia , Disfunção Ventricular Esquerda/etiologia
7.
Org Biomol Chem ; 20(45): 8944-8951, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36325908

RESUMO

A sustainable and environment-friendly approach for the regioselective acylation of 1-methyl-3-phenyl quinoxaline-2(1H)-ones has been developed in water. The present protocol requires palladium acetate as a catalyst and exhibits a wide substrate scope by employing commercially available, non-toxic aldehydes, benzyl alcohols and toluenes as acyl surrogates. The mechanistic studies demonstrated the adoption of a free radical pathway for this transformation. Furthermore, the established protocol exhibits excellent regioselectivity and high functional group tolerance and is amenable to the gram scale. The established synthetic method also provides a practical and convenient route for the late-stage functionalization of some potential drug candidates.


Assuntos
Paládio , Água , Estrutura Molecular , Quinoxalinas , Catálise
8.
Echocardiography ; 39(11): 1401-1411, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36266740

RESUMO

OBJECTIVE: Cardiac involvement in recovered COVID-19 patients assessed by cardiac magnetic resonance imaging (MRI). METHODS: Subjects recently recovered from COVID-19 and with an abnormal left ventricular global longitudinal strain were enrolled. Cardiac MRI in all the enrolled subjects was done at baseline (within 30-90 days following recovery from COVID-19) with a follow-up scan at 6 months in individuals with an abnormal baseline scan. Additionally, 20 age-and sex-matched individuals were enrolled as healthy controls (HCs). RESULTS: All the 30 enrolled subjects were symptomatic during active COVID-19 disease and were categorized as mild: 11 (36.7%), moderate: 6 (20%), and severe: 13 (43.3%). Of the 30 patients, 16 (53.3%) had abnormal CMR findings. Myocardial edema was reported in 12 (40%) patients while 10 (33.3%) had late gadolinium enhancement (LGE). No difference was observed in terms of conventional left ventricular (LV) parameters; however, COVID-19-recovered patients had significantly lower right ventricular (RV) ejection fraction, RV stroke volume, and RV cardiac index compared to HCs. Follow-up scan was abnormal in 4/16 (25%) with LGE persisting in three patients (who had severe COVID-19 [3/4;75%]). Subjects with severe COVID-19 had a greater frequency of LGE (53.8%) and myocardial edema (61.5%) as compared to mild and moderate cases. Myocardial T1 (1284 ± 43.8 ms vs. 1147.6 ± 68.4 ms; p < .0001) and T2 values (50.8 ± 16.7 ms vs. 42.6 ± 3.6 ms; p = .04) were significantly higher in post COVID-19 subjects compared to HCs. Similarly, T1 and T2 values of severe COVID-19 patients were significantly higher compared to mild and moderate cases. CONCLUSIONS: An abnormal CMR was seen in half of the recovered patients with persistent abnormality in one-fourth at 6 months. Our study suggests a need for closer follow-up among recovered subjects in order to evaluate for long-term cardiovascular sequelae. COVID-19 causes structural changes in the myocardium in a small segment of patients with partial spontaneous resolution.


Assuntos
COVID-19 , Imagem Cinética por Ressonância Magnética , Humanos , Seguimentos , Imagem Cinética por Ressonância Magnética/métodos , COVID-19/complicações , Meios de Contraste , Gadolínio , Volume Sistólico , Miocárdio/patologia , Imageamento por Ressonância Magnética , Função Ventricular Esquerda , Valor Preditivo dos Testes
9.
Indian Pacing Electrophysiol J ; 22(2): 70-76, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35101582

RESUMO

INTRODUCTION: Cardiovascular dysautonomia comprising postural orthostatic tachycardia syndrome (POTS) and orthostatic hypotension (OH) is one of the presentations in COVID-19 recovered subjects. We aim to determine the prevalence of cardiovascular dysautonomia in post COVID-19 patients and to evaluate an Artificial Intelligence (AI) model to identify time domain heart rate variability (HRV) measures most suitable for short term ECG in these subjects. METHODS: This observational study enrolled 92 recently COVID-19 recovered subjects who underwent measurement of heart rate and blood pressure response to standing up from supine position and a 12-lead ECG recording for 60 s period during supine paced breathing. Using feature extraction, ECG features including those of HRV (RMSSD and SDNN) were obtained. An AI model was constructed with ShAP AI interpretability to determine time domain HRV features representing post COVID-19 recovered state. In addition, 120 healthy volunteers were enrolled as controls. RESULTS: Cardiovascular dysautonomia was present in 15.21% (OH:13.04%; POTS:2.17%). Patients with OH had significantly lower HRV and higher inflammatory markers. HRV (RMSSD) was significantly lower in post COVID-19 patients compared to healthy controls (13.9 ± 11.8 ms vs 19.9 ± 19.5 ms; P = 0.01) with inverse correlation between HRV and inflammatory markers. Multiple perceptron was best performing AI model with HRV(RMSSD) being the top time domain HRV feature distinguishing between COVID-19 recovered patients and healthy controls. CONCLUSION: Present study showed that cardiovascular dysautonomia is common in COVID-19 recovered subjects with a significantly lower HRV compared to healthy controls. The AI model was able to distinguish between COVID-19 recovered patients and healthy controls.

10.
J Urol ; 205(2): 370-382, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32915080

RESUMO

PURPOSE: Cancer specific survival for men with early stage (I to IIB) testicular germ cell tumors is greater than 90% with any management strategy. The data regarding the comparative effectiveness of surveillance, primary chemotherapy, radiotherapy and retroperitoneal lymph node dissection were synthesized with a focus on oncologic outcomes, patient reported outcomes, and short and long-term toxicities. MATERIALS AND METHODS: PubMed®, Embase® and the Cochrane Central Register of Controlled Trials were searched from 1980 to 2018 for studies addressing the effectiveness of surveillance, chemotherapy, radiotherapy and retroperitoneal lymph node dissection, according to pathology and clinical stage, for men with an early stage testicular germ cell tumor. RESULTS: Cancer specific survival ranged from 94% to 100% for patients with early stage testicular germ cell tumors regardless of tumor histology and initial management strategy. For men with seminoma the median cancer specific survival was 99.7% (range 97% to 100%), 99.5% (96.8% to 100%) and 100% (100% to 100%) among those managed by surveillance, radiotherapy and chemotherapy, respectively. Median cancer specific survival for men with nonseminomatous testicular germ cell tumors was 100% (range 98.6% to 100%), 100% (96.9% to 100%) and 100% (94% to 100%) when managed by surveillance, retroperitoneal lymph node dissection and chemotherapy, respectively. Recurrence rates and toxicities varied by management strategy. For men with seminoma surveillance, chemotherapy and radiotherapy were associated with median recurrence rates of 15%, 2% and 3.7%, respectively. For men with nonseminomatous testicular germ cell tumors the median recurrence rates were 20.5%, 3.3% and 11.1% for surveillance, chemotherapy and retroperitoneal lymph node dissection, respectively. Surveillance was associated with minimal toxicities compared to other approaches. Primary chemotherapy had the highest rate of short-term toxicities and was associated with long-term risks of metabolic syndrome, hypogonadism, renal impairment, neuropathy, infertility and secondary malignancies. Toxicities with radiotherapy included acute dermatitis and long-term gastrointestinal complications, infertility and high rates of secondary malignancies (2% to 3%). Patients undergoing retroperitoneal lymph node dissection had significant risk of toxicity perioperatively and long-term infertility in men with anejaculation. Transient detriments in patient reported outcomes and quality of life were noted with all management options. CONCLUSIONS: Men with early stage testicular germ cell tumors experience excellent cancer specific survival regardless of management strategy. Management options, however, differ in terms of associated recurrence rates, short and long-term toxicities, and patient reported outcomes. The profile for each approach should be clearly communicated to patients and matched with patient preferences to offer the best individual outcome.


Assuntos
Neoplasias Embrionárias de Células Germinativas/terapia , Neoplasias Testiculares/terapia , Humanos , Excisão de Linfonodo/métodos , Masculino , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/radioterapia , Neoplasias Embrionárias de Células Germinativas/cirurgia , Espaço Retroperitoneal , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/radioterapia , Neoplasias Testiculares/cirurgia , Fatores de Tempo , Resultado do Tratamento , Conduta Expectante
11.
World J Urol ; 39(9): 3399-3405, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33710425

RESUMO

PURPOSE: Increasing use and resolution of testicular ultrasound imaging has resulted in a greater diagnosis of non-palpable small testicular masses and subsequent over-treatment with orchiectomy. Our aim was to determine the diagnostic accuracy of testicular ultrasound to accurately determine the pathologic size of small testicular masses (SMTMs) and to evaluate the association of various measurements with benign pathology. METHODS: Retrospectively, an institutional testicular cancer database was reviewed to evaluate the patients who underwent an orchiectomy for a testicular mass seen on ultrasound from 2003 to 2017. Three-dimensional measurements were compared from the ultrasound and pathology specimens, including other measures such as tumor volume and percentage of testicular volume. Finally, the predictive accuracy of maximum diameter and tumor volume to predict benign pathology was evaluated using receiver-operating curve analysis. RESULTS: We identified 208 patients and showed that ultrasound significantly underestimated sub-centimeter testicular masses (mean difference 0.56 cm, 95%CI 0.89-0.14, p = 0.004) and testicular masses between 1 and < 2 cm (mean difference 0.50 cm, 95%CI 0.97-0.15, p = 0.009). Tumor volume measured on ultrasound was consistently similar to pathologic tumor volume across all sizes and was significantly correlated (Spearman's Rho = 0.81). Mass volume had a greater predictive accuracy for benign pathology than maximum diameter using a 1 cm cut-off (AUC 0.65 vs 0.60). CONCLUSION: Using the maximal diameter, testicular ultrasound significantly miscalculated the pathologic dimensions of masses less than 2 cm compared to orchiectomy specimens. Volumetric measurements may better represent actual tumor sizes for SMTMs and may be a more useful measure for identifying those a higher risk for benign pathology, however, further studies are required.


Assuntos
Precisão da Medição Dimensional , Neoplasias Testiculares/diagnóstico por imagem , Neoplasias Testiculares/patologia , Carga Tumoral , Adulto , Correlação de Dados , Humanos , Masculino , Estudos Retrospectivos , Ultrassonografia
12.
Echocardiography ; 38(10): 1722-1730, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34555203

RESUMO

OBJECTIVES: Myocardial injury during active coronavirus disease-2019 (COVID-19) infection is well described; however, its persistence during recovery is unclear. We assessed left ventricle (LV) global longitudinal strain (GLS) using speckle tracking echocardiography (STE) in COVID-19 recovered patients and its correlation with various parameters. METHODS: A total of 134 subjects within 30-45 days post recovery from COVID-19 infection and normal LV ejection fraction were enrolled. Routine blood investigations, inflammatory markers (on admission) and comprehensive echocardiography including STE were done for all. RESULTS: Of the 134 subjects, 121 (90.3%) were symptomatic during COVID-19 illness and were categorized as mild: 61 (45.5%), moderate: 50 (37.3%) and severe: 10 (7.5%) COVID-19 illness. Asymptomatic COVID-19 infection was reported in 13 (9.7%) patients. Subclinical LV and right ventricle (RV) dysfunction were seen in 40 (29.9%) and 14 (10.5%) patients, respectively. Impaired LVGLS was reported in 1 (7.7%), 8 (13.1%), 22 (44%) and 9 (90%) subjects with asymptomatic, mild, moderate and severe disease, respectively. LVGLS was significantly lower in patients recovered from severe illness(mild: -21 ± 3.4%; moderate: -18.1 ± 6.9%; severe: -15.5 ± 3.1%; p < 0.0001). Subjects with reduced LVGLS had significantly higher interleukin-6 (p < 0.0001), C-reactive protein (p = 0.001), lactate dehydrogenase (p = 0.009), serum ferritin (p = 0.03), and troponin (p = 0.01) levels during index admission. CONCLUSIONS: Subclinical LV dysfunction was seen in nearly a third of recovered COVID-19 patients while 10.5% had RV dysfunction. Our study suggests a need for closer follow-up among COVID-19 recovered subjects to elucidate long-term cardiovascular outcomes.


Assuntos
COVID-19 , Disfunção Ventricular Esquerda , Ecocardiografia , Humanos , SARS-CoV-2 , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda
13.
Monaldi Arch Chest Dis ; 92(3)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34918500

RESUMO

Coronary artery anomalies (CAAs) are a diverse group of disorders with varied clinical presentation and pathophysiological mechanisms. A majority of these anomalies are asymptomatic and often an incidental finding on coronary angiogram or autopsy. This retrospective study included 28,800 patients who underwent coronary angiography from 2016 to 2020. The coronary angiograms were reviewed by two independent reviewers and CAAs were documented. CAAs were classified into i) anomalies of coronary artery connection, ii) anomalies of intrinsic coronary arterial anatomy and iii) anomalies of myocardial/coronary artery interaction as proposed by the European Society of Cardiology. Of the 28,800 coronary angiograms, CAAs were present in 4.12% with anomalies in the left coronary artery (LCA) being most common. Anomalies of coronary artery connection were most common (48.48%) followed by anomalies of myocardial/coronary artery interaction (34.49%) and anomalies of intrinsic coronary artery anatomy (17.03%). Among anomalies of coronary artery connection, absent left main trunk or split LCA with separate origins of left anterior descending coronary artery and left circumflex coronary artery from the left coronary sinus of Valsalva (22.59%) was most common. An intramural course or "myocardial bridge" had an incidence of 1.16%  while incidence of coronary artery fistulae (CAF) was 0.115%.


Assuntos
Doença da Artéria Coronariana , Anomalias dos Vasos Coronários , Adulto , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Anomalias dos Vasos Coronários/diagnóstico por imagem , Anomalias dos Vasos Coronários/epidemiologia , Humanos , Índia/epidemiologia , Prevalência , Estudos Retrospectivos , Centros de Atenção Terciária
14.
J Cell Biochem ; 121(2): 1156-1168, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31464004

RESUMO

Triple-negative breast cancers (TNBCs) represent 15% to 20% of all breast cancers and are often associated with poor prognosis. The lack of targeted therapies for TNBCs contributes to higher mortality rates. Aberrations in the phosphoinositide-3-kinase (PI3K) and mitogen-activated protein kinase pathways have been linked to increased breast cancer proliferation and survival. It has been proposed that these survival characteristics are enhanced through compensatory signaling and crosstalk mechanisms. While the crosstalk between PI3K and extracellular signal-regulated kinase 1/2 (ERK1/2) pathways has been characterized in several systems, new evidence suggests that MEK5/ERK5 signaling is a key component in the proliferation and survival of several aggressive cancers. In this study, we examined the effects of dual inhibition of PI3K/protein kinase B (Akt) and MEK5/ERK5 in the MDA-MB-231, BT-549, and MDA-MB-468 TNBC cell lines. We used the Akt inhibitor ipatasertib, ERK5 inhibitors XMD8-92 and AX15836, and the novel MEK5 inhibitor SC-1-181 to investigate the effects of dual inhibition. Our results indicated that dual inhibition of PI3K/Akt and MEK5/ERK5 signaling was more effective at reducing the proliferation and survival of TNBCs than single inhibition of either pathway alone. In particular, a loss of Bad phosphorylation at two distinct sites was observed with dual inhibition. Furthermore, the inhibition of both pathways led to p21 restoration, decreased cell proliferation, and induced apoptosis. In addition, the dual inhibition strategy was determined to be synergistic in MDA-MB-231 and BT-549 cells and was relatively nontoxic in the nonneoplastic MCF-10 cell line. In summary, the results from this study provide a unique prospective into the utility of a novel dual inhibition strategy for targeting TNBCs.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , MAP Quinase Quinase 5/metabolismo , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/metabolismo , Apoptose/efeitos dos fármacos , Benzodiazepinonas/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Humanos , MAP Quinase Quinase 5/antagonistas & inibidores , Proteína Quinase 7 Ativada por Mitógeno/antagonistas & inibidores , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Piridonas/farmacologia , Pirimidinas/farmacologia , Pirimidinonas/farmacologia
15.
J Urol ; 203(5): 894-901, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31609176

RESUMO

PURPOSE: We synthesized evidence on the comparative performance characteristics, benefits and harms of diagnostic imaging modalities used in combination with serum tumor markers for clinical staging of testicular germ cell tumors. The diagnostic imaging modalities included computerized tomography, magnetic resonance imaging, positron emission tomography and chest radiographs. MATERIALS AND METHODS: Paired reviewers independently searched PubMed, Embase® and the Cochrane Central Register of Controlled Trials from 1980 to 2018 using title-abstract and full-text screening to identify original studies of the use of computerized tomography, magnetic resonance imaging, positron emission tomography, chest radiographs and serum tumor markers for the clinical staging of early stage testicular germ cell tumors. RESULTS: We found 21 studies of a total of 1,702 patients. With significant bias and limitations to the data, the performance characteristics of computerized tomography, magnetic resonance imaging and positron emission tomography for staging of the retroperitoneum were similar, with median sensitivity ranging from 67% to 80% and median specificity ranging from 95% to 100%. Computerized tomography of the chest (median sensitivity 100%) was more sensitive than a chest radiograph (median sensitivity 76%), especially in men with nonseminomatous germ cell tumors. The addition of serum tumor markers to diagnostic imaging improved staging sensitivity from 38% to 41% to 59% to 60%. No study specifically reported on harms of the imaging modalities. CONCLUSIONS: The combination of axial imaging with computerized tomography or magnetic resonance imaging and serum tumor markers demonstrates optimal performance characteristics for staging early stage testicular germ cell tumors. There is little use for chest computerized tomography in men with seminoma, negative abdominal imaging and negative serum tumor markers.


Assuntos
Diagnóstico por Imagem/métodos , Detecção Precoce de Câncer/métodos , Estadiamento de Neoplasias/métodos , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Neoplasias Testiculares/diagnóstico , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Reprodutibilidade dos Testes
16.
J Urol ; 204(1): 33-41, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31967523

RESUMO

PURPOSE: We performed a systematic review of studies assessing the diagnosis and effectiveness of management strategies for germ cell neoplasia in situ. MATERIALS AND METHODS: Paired investigators independently searched for studies on the diagnosis and management of testicular germ cell neoplasia in situ using PubMed®, Embase® and the Cochrane Central Register of Controlled Trials from January 1, 1980 through August 2018. The reviewers then extracted data and assessed quality. RESULTS: Eighteen studies met inclusion criteria. Among patients with a testicular germ cell tumor the prevalence of contralateral germ cell neoplasia in situ was 4.0% to 8.1%. No significant difference in the risk of metachronous malignancy was identified between unscreened groups vs those with routine contralateral testicular screening (cumulative incidence 1.9% vs 3.1%, p=0.097, respectively). Patients who presented with a history of testicular atrophy, age less than 40 years or cryptorchidism had an elevated risk of germ cell neoplasia in situ. In patients with germ cell neoplasia in situ the use of 18 to 20 Gy radiation therapy demonstrated the lowest rate of disease on followup biopsies (0% to 2.5%), compared to a median of 30% on biopsies in patients treated with cisplatin based chemotherapy. Carboplatin based treatment regimens demonstrated positive disease in 66% to 75% on repeat biopsies. Rates of treatment related hypogonadism were 30.8% to 38.5% and 13% to 20% for patients treated with 18 to 20 Gy and cisplatin based chemotherapy, respectively. CONCLUSIONS: In patients with a testicular germ cell tumor the risk of having contralateral germ cell neoplasia in situ is 4% to 8%, with a greater risk in patients with testicular atrophy, cryptorchidism or age less than 40 years. The risk is high enough to support use of contralateral testicular biopsy in patients with these risk factors for germ cell neoplasia in situ. However, routine screening is not advised. Radiation therapy with 18 to 20 Gy was associated with much better eradication of germ cell neoplasia in situ than chemotherapy. Chemotherapy may eradicate germ cell neoplasia in situ in up to two-thirds of patients undergoing chemotherapy as adjuvant treatment for a primary germ cell tumor. Further research and data are needed to strengthen many aspects of the evidence base.


Assuntos
Neoplasias Embrionárias de Células Germinativas/diagnóstico , Neoplasias Embrionárias de Células Germinativas/terapia , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/terapia , Terapia Combinada , Humanos , Masculino , Medição de Risco , Fatores de Risco
17.
J Urol ; 203(6): 1101-1108, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31898919

RESUMO

PURPOSE: The impact of preoperative chemotherapy in patients with upper urinary tract urothelial carcinoma remains poorly investigated. We assessed the rates of pathological complete response (pT0N0/X) and downstaging (pT1N0/X or less) at radical nephroureterectomy after preoperative chemotherapy and evaluated their impact on survival. MATERIALS AND METHODS: This was an international observational study of patients who underwent preoperative chemotherapy and radical nephroureterectomy for high risk upper tract urothelial carcinoma between 2005 and 2017. Multiple imputation of chained equations was applied to account for missing values. Logistic regression analyses were performed to identify predictors of pathological response. Cox proportional hazard regression models were used to estimate recurrence-free survival, cancer specific survival and overall survival. RESULTS: A total of 267 patients met our inclusion criteria. Among included patients 82 (31%) received methotrexate, vinblastine, doxorubicin and cisplatin; 123 (46%) gemcitabine and cisplatin; 25 (9%) gemcitabine and carboplatin; and 32 (12%) other regimens. The overall rates of pathological complete response and pathological downstaging were 10.1% and 44.9%, respectively. On multivariable analysis the use of gemcitabine and cisplatin, and gemcitabine and carboplatin was not statistically different from methotrexate, vinblastine, doxorubicin and cisplatin in achieving pathological complete response and pathological downstaging, respectively. The number of administered cycles did not appear to have an effect on pathological responses. Pathological downstaging was the strongest prognostic factor for recurrence-free survival (HR 0.2, p <0.001), cancer specific survival (HR 0.19, p <0.001) and overall survival (HR 0.40, p <0.001). CONCLUSIONS: Pathological downstaging after preoperative chemotherapy is a robust prognostic factor at radical nephroureterectomy and is associated with improved survival outcomes. Although preoperative chemotherapy appears to be effective, well designed prospective studies are still needed.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células de Transição/tratamento farmacológico , Terapia Neoadjuvante , Nefrectomia , Ureter/cirurgia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Antineoplásicos/uso terapêutico , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/patologia , Carcinoma de Células de Transição/cirurgia , Quimioterapia Adjuvante , Esquema de Medicação , Feminino , Seguimentos , Humanos , Modelos Logísticos , Masculino , Estadiamento de Neoplasias , Estudos Retrospectivos , Risco , Análise de Sobrevida , Resultado do Tratamento , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia
18.
J Clin Gastroenterol ; 54(10): 891-897, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32168133

RESUMO

BACKGROUND: Recent guidelines have recommended screening for nonalcoholic fatty liver disease (NAFLD) and case finding of advanced disease with fibrosis in patients with type-2 diabetes (T2D). The aim of this study is to assess the accuracy of commonly used noninvasive scores to predict the presence of advanced fibrosis (AF) in a large cohort of diabetics in real-life settings. PATIENTS AND METHODS: Using International Classification of Diseases, Ninth Revision (ICD-9) codes, all patients with the diagnosis of T2D who had a liver biopsy for suspected NAFLD between January 2000 and December 2015, were identified and analyzed. Patients with secondary causes of hepatic steatosis were excluded. AST/ALT ratio, aspartate aminotransferase to platelet ratio index (APRI), fibrosis-4 (FIB-4) index, and Nonalcoholic fatty liver disease Fibrosis Score (NFS) were calculated to predict advanced disease. Sensitivity, specificity, and area under the receiver operator curve were calculated and compared with liver biopsies to predict the overall accuracy of each score. RESULTS: A total of 1319 patients with T2D underwent liver biopsy for suspected NAFLD. After exclusions, 1,157 subjects were included in the final analysis. Our cohort consisted of 64.6% females and 88.4% were whites. Overall, 85% of the population was overweight or obese (body mass index>25 kg/m). Liver biopsy showed 31.7% with AF [Nonalcoholic Steatohepatitis Clinical Research Network (NASH-CRN) stage 3 to 4]. In comparison to liver biopsy, for the diagnosis of AF, AST/ALT>1.4, APRI>1.5, FIB-4>2.67, and NFS>0.676 had reasonable specificities of 84.2%, 97.4%, 69.9%, and 93% but poor sensitivities of 27.4%, 16.5%, 6.7%, and 44.1%, respectively. Even at lower cutoff values of AST/ALT≥1, APRI≥1, and FIB-4≥1.45 sensitivities remained low at 60.7%, 27.9%, and 72.6%, respectively, except for NFS ≥-1.455 with sensitivity of 94.6%, but at this cutoff, its specificity decreased to 16.9%. The area under the receiver operator curve to detect AF was 0.62, 0.74, 0.77, and 0.72, respectively. CONCLUSIONS: In this large cohort of adult patients with T2D and NAFLD, commonly used fibrosis scores had reasonable specificity, but poor sensitivity for detecting AF in diabetics. The development of reliable biomarkers for NAFLD/NASH in diabetics is urgently needed.


Assuntos
Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Adulto , Alanina Transaminase , Aspartato Aminotransferases , Biópsia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/patologia , Feminino , Fibrose , Humanos , Fígado/patologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/patologia , Contagem de Plaquetas , Índice de Gravidade de Doença
19.
Dig Dis Sci ; 65(11): 3341-3349, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31981110

RESUMO

BACKGROUND AND AIMS: Obesity and diabetes are risk factors for advanced alcoholic liver disease, and both are components of the metabolic syndrome. We aimed to assess the prevalence of metabolic syndrome and its components in a contemporary US cohort of adults with alcoholic liver disease and compare it to a historic cohort to assess changes over time. METHOD: Individuals 18 years or older who participated in the National Health and Nutrition Examination Survey during 2009-2014 and 1999-2001 were used as the contemporary and historic cohort, respectively. Alcoholic liver disease was defined as excessive alcohol consumption (men: ≥ 3 drinks/day; women: ≥ 2 drinks/day) and elevated alanine aminotransferase. Metabolic syndrome definition was based on the updated International Diabetes Federation criteria. Data are presented as mean ± standard error or unweighted frequency. A logistic regression analysis was performed to assess differences in metabolic syndrome components between the two period cohorts while adjusting for central obesity. RESULTS: The mean age for our contemporary cohort was 41.9, 66.1% being male. Central obesity was present in 66.3%, type 2 diabetes in 18.7%, low high-density lipoprotein in 28.3%, hypertriglyceridemia in 44.8%, and hypertension in 54.7%. 36.9% met the criteria for metabolic syndrome. Compared to the historic cohort, patients in the contemporary cohort were more likely to have central obesity (50% vs. 66%, p = 0.002), metabolic syndrome (26% vs. 37%, p = 0.044), and type 2 diabetes (12% vs. 19%, p = 0.099). CONCLUSIONS: Prevalence of both obesity and metabolic syndrome is increasing in alcoholic liver disease patients. Further studies are required to investigate effective interventions to avoid disease progression in these high-risk patients.


Assuntos
Fígado Gorduroso Alcoólico/epidemiologia , Síndrome Metabólica/epidemiologia , Obesidade/epidemiologia , Adulto , Feminino , Humanos , Testes de Função Hepática , Masculino , Inquéritos Nutricionais , Prevalência , Fatores de Risco , Estados Unidos/epidemiologia
20.
Dig Dis Sci ; 65(4): 978-986, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31187324

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) has become the most common form of chronic liver disease in the USA. Interestingly, most patients with NAFLD are unaware of having any liver disease (LD). We aimed to assess the awareness of suspected NAFLD and factors associated with being aware of LD. METHODS: Adult subjects with suspected NAFLD (BMI > 25) with elevated ALT in the absence of secondary causes of LD who participated in the continuous national health and nutrition examination survey (NHANES) during 2001-2016 were identified and analyzed. Trends of NAFLD awareness were then assessed in periods of 4 years each. Multivariable logistic regression analysis was performed to assess factors associated with LD awareness. RESULTS: A total of 7033 subjects were included in the final analysis (1731, 1757, 1711, and 1834 subjects for the periods of 2001-2004, 2005-2008, 2009-2012, and 2013-2016, respectively). Over the study duration, an increase in BMI, waist circumference, diabetes, and HbA1c; and a decrease in the number of smokers, platelets count, bilirubin, total cholesterol, and LDL level were noticed (p < 0.001). Awareness of having LD across study periods has increased over time from 1.5% in the 2001-2004 periods to 3.1% in the 2013-2016 periods. Multivariable logistic regression analysis showed that older age, ethnicity (non-black), having fewer drinks/week, metabolic syndrome, higher ALT, ALP, and GGT were associated with being aware of having LD. CONCLUSIONS: Awareness of having LD among subjects with suspected NAFLD has increased over the last two decades, but more than 95% of these patients are still unaware of having LD. Educational programs to increase awareness of LD and risk factors for NAFLD should be implemented on a large scale. CLINICAL TRIAL REGISTRATION NUMBER: Not required, as we used de-identified NHANES data.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Inquéritos Nutricionais , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais/métodos , Fatores de Risco , Estados Unidos/epidemiologia
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