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1.
Small ; 18(50): e2200272, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36319476

RESUMO

For most electrodes fabricated with carbon, transition metal compounds, or conductive polymers, the capacitance may deteriorate with cyclic charging and discharging. Thus, an electrochemically stable supercapacitor has long been pursued by researchers. In this work, the hierarchical structure of balsa wood is preserved in the converted carbon which is used as a supporting framework to fabricate electrodes for supercapacitors. Well-grown carbon nanotubes (CNTs) on interior and exterior surfaces of balsa carbon channels provide two advantages including 1) offering more specific surface area to boost capacitance via electric double layer capacitance and 2) offering more active Fe and Ni sites to participate in the redox reaction to enhance capacitance of the balsa carbon/CNTs electrode. The balsa carbon/CNTs demonstrate an excellent area capacitance of 1940 mF cm-2 . As active sites on Ni and Fe catalysts and inner walls of CNTs are gradually released, the capacitance increases 66% after 4000 charge-discharge cycles. This work brings forward a strategy for the rational design of high-performance biomass carbon coupled with advanced nanostructures for energy storage.

2.
Breast Cancer Res Treat ; 181(3): 679-689, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32367460

RESUMO

PURPOSE: Discordance between HER2 expression in tumor tissue (tHER2) and HER2 status on circulating tumor cells (cHER2) has been reported. It remains largely underexplored whether patients with tHER2-/cHER2+ can benefit from anti-HER2 targeted therapies. METHODS: cHER2 status was determined in 105 advanced-stage patients with tHER2- breast tumors. Association between cHER2 status and progression-free survival (PFS) was analyzed by univariate and multivariate Cox models and survival differences were compared by Kaplan-Meier method. RESULTS: Compared to the patients with low-risk cHER2 (cHER2+ < 2), those with high-risk cHER2 (cHER2+ ≥ 2) had shorter survival time and an increased risk for disease progression (hazard ratio [HR] 2.16, 95% confidence interval [CI] 1.20-3.88, P = 0.010). Among the patients with high-risk cHER2, those who received anti-HER2 targeted therapies had improved PFS compared with those who did not (HR 0.30, 95% CI 0.10-0.92, P = 0.035). In comparison, anti-HER2 targeted therapy did not affect PFS among those with low-risk cHER2 (HR 0.70, 95% CI 0.36-1.38, P = 0.306). Similar results were obtained after adjusting covariates. A longitudinal analysis of 67 patients with cHER2 detected during follow-ups found that those whose cHER2 status changed from high-risk at baseline to low-risk at first follow-up exhibited a significantly improved survival compared to those whose cHER2 remained high-risk (median PFS: 11.7 weeks vs. 2.0 weeks, log-rank P = 0.001). CONCLUSION: In advanced-stage breast cancer patients with tHER2- tumors, cHER2 status has the potential to guide the use of anti-HER2 targeted therapy in patients with high-risk cHER2.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/patologia , Células Neoplásicas Circulantes/patologia , Receptor ErbB-2/metabolismo , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Células Neoplásicas Circulantes/metabolismo , Receptor ErbB-2/genética , Taxa de Sobrevida
3.
J Phys Chem Lett ; 14(47): 10693-10699, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37988698

RESUMO

Activated carbon (AC)-based materials have shown promising performance in carbon capture, offering low cost and sustainable sourcing from abundant natural resources. Despite ACs growing as a new class of materials, theoretical guidelines for evaluating their viability in carbon capture are a crucial research gap. We address this gap by developing a hierarchical guideline, based on fundamental gas-solid interaction strength, that underpins the success and scalability of AC-based materials. The most critical performance indicator is the CO2 adsorption energy, where an optimal range (-0.41 eV) ensures efficiency between adsorption and desorption. Additionally, we consider thermal stability and defect sensitivity to ensure consistent performance under varying conditions. Further, selectivity and capacity play significant roles due to external variables such as partial pressure of CO2 and other ambient air gases (N2, H2O, O2), bridging the gap between theory and reality. We provide actionable examples by narrowing our options to methylamine- and pyridine-grafted graphene.

4.
JNMA J Nepal Med Assoc ; 60(245): 90-92, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35199668

RESUMO

Penetrating neck injuries causing rupture of sternocleidomastoid muscle along with transection of major vessels of the neck have significant morbidity and mortality due to the risk of severe hemorrhage and cerebral infarction. However, there are no universal guidelines for the management of penetrating neck injuries. Here, we report a case of a 67-year-old female with a lacerated wound on the left side of the neck with a complete transection of the left sternocleidomastoid muscle along with transection of internal jugular vein and two superficial branches of internal carotid artery following penetrating injury to the neck by a bamboo stick. It was managed by emergency wound exploration with ligation of the injured vessels with repair of sternocleidomastoid muscle. Post-operatively the hemorrhage was controlled and the patient was discharged on the fourth postoperative day. Thus, in a case of penetrating injury to the neck, prompt surgical wound exploration is beneficial.


Assuntos
Lesões do Pescoço , Lesões do Sistema Vascular , Ferimentos Penetrantes , Idoso , Feminino , Humanos , Ligadura , Pescoço/cirurgia , Lesões do Pescoço/complicações , Lesões do Pescoço/diagnóstico , Lesões do Pescoço/cirurgia , Lesões do Sistema Vascular/diagnóstico , Lesões do Sistema Vascular/etiologia , Lesões do Sistema Vascular/cirurgia , Ferimentos Penetrantes/complicações , Ferimentos Penetrantes/diagnóstico , Ferimentos Penetrantes/cirurgia
5.
Ann Med Surg (Lond) ; 74: 103228, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35127064

RESUMO

In agrarian countries where bulls are used for farming and stock breeding, bull horn injuries are common. Bull horn injuries range from blunt trauma to penetrating injuries, which can cause massive hemorrhage. Vascular injuries to the limbs by goring bull horn injury usually involve transection of vessels but rarely cause intimal tear with thrombus formation. Here, we report an unusual case of a 33-year-old male with circumferential intimal tear with thrombosis in the subintimal region of the right superficial femoral artery without transection of the vessel following penetrating injury to the right thigh caused by a bull's horn. There was a pulse deficit above the popliteal artery, and Doppler ultrasonography revealed decreased flow indicative of underlying femoral vessel injury for which the wound was surgically explored. It was followed by right superficial femoral arteriotomy at the site of the thrombus with the evacuation of a 6 cm long clot, revealing a 6 cm long endothelial injury in the same vessel. Next, an interposition reversed saphenous graft was placed in the same location. Following this, Doppler ultrasonography was done that revealed restoration of blood flow to the site of thrombosis. Thus, in a case of bull horn injury, thrombosis should be ruled out with prompt surgical wound exploration despite the presence of an intact vessel.

6.
Mol Cancer Res ; 19(10): 1763-1777, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34021072

RESUMO

Bone is a common site of cancer metastasis, including cancers such as breast, prostate, and multiple myeloma. Disseminated tumor cells (DTC) shed from a primary tumor may travel to bone and can survive undetected for years before proliferating to form overt metastatic lesions. This period of time can be defined as metastatic latency. Once in the metastatic microenvironment, DTCs engage in intercellular communication with surrounding stromal cells, which can influence cancer cell survival, proliferation, and ultimately disease progression. The role of the surrounding tumor microenvironment in regulating DTC fate is becoming increasingly recognized. We have previously shown that in the bone microenvironment, osteoblasts are "educated" by interactions with breast cancer cells, and these "educated" osteoblasts (EO) produce soluble factors that regulate cancer cell proliferation. In this study, we provide evidence indicating that EOs produce small extracellular vesicles (sEV) that suppress breast cancer proliferation, in part through regulation of ERK1/2 signaling. In addition, using EdU-incorporation assays and propidium iodide staining we demonstrate that exposure to EO-derived sEVs decreases breast cancer cell entry to S-phase of cell cycle. We also have evidence that particular microRNAs, including miR-148a-3p, are enriched in EO-derived sEVs, and that miR-148a-3p is capable of regulating breast cancer proliferation. IMPLICATIONS: These findings underscore the importance of sEV-mediated communication in the earlier stages of cancer progression, and suggest that EO-derived sEVs may be one mechanism by which the bone microenvironment suppresses breast cancer cell proliferation.


Assuntos
Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Proliferação de Células/fisiologia , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Células 3T3 , Animais , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Comunicação Celular/fisiologia , Ciclo Celular/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Feminino , Camundongos , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Osteoblastos/metabolismo , Osteoblastos/patologia , Microambiente Tumoral/fisiologia
7.
Stem Cells Dev ; 28(21): 1424-1433, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31495275

RESUMO

Dome formation can occur in cultured tubular epithelial cells originating from various tissues, including the mammary gland and the kidney. The isolation and characterization of normal kidney epithelial stem cells that give rise to dome-forming tubular cells have never been reported. We attempted to isolate and characterize canine kidney epithelial stem cells using a simple cell culture method that we have previously used to isolate other adult human stem cells. Dome-forming kidney epithelial cells were derived from dissociated adult canine kidney tissues that were cultured in a modified keratinocyte serum-free medium supplemented with N-acetyl-l-cysteine, l-ascorbic acid 2-phosphate, nicotinamide, and fetal bovine serum. These cells exhibited high self-renewal capacity in long-term culture (growth for >13 months and 30 cumulative population doublings) and exhibited characteristics of stem cells, including (1) deficiency in gap junctional intercellular communication, (2) anchorage-independent growth, (3) expression of stem cell markers octamer-binding transcription factor 4 and SRY (sex determining region Y)-box 2, (4) expression of cell surface markers CD24 and CD133, and (5) multipotent differentiation into osteoblasts, adipocytes, chondrocytes, and dome-forming tubular cells. Most of these characteristics are shared by the well-known canine renal tubule-derived immortalized Madin-Darby Canine Kidney cell line. Furthermore, the putative canine kidney stem cells developed in this study formed budding tubule-like organoids on Matrigel and required high cell density (>4,000 cells/cm2) for sustained growth and confluency for dome formation. The signal transducer and activator of transcription-3 (STAT3) phosphorylation inhibitor, AG490, inhibited colony-forming efficiency and dome formation, whereas lipopolysaccharide, an activator of STAT3, increased colony-forming efficiency in a dose-dependent manner. These results are consistent with the hypothesis that high cell density induces STAT3 expression, which promotes both stem cell self-renewal and differentiation into tubular cells. Our novel cell culture method should be useful for the future development of normal human kidney stem cells for clinical applications and for studying mechanisms of nephrotoxicity.


Assuntos
Células Epiteliais/citologia , Túbulos Renais/citologia , Células-Tronco Multipotentes/citologia , Fator de Transcrição STAT3/metabolismo , Antígeno AC133/metabolismo , Animais , Antígeno CD24/metabolismo , Linhagem Celular , Terapia Baseada em Transplante de Células e Tecidos/métodos , Cães , Inibidores Enzimáticos/farmacologia , Falência Renal Crônica/terapia , Lipopolissacarídeos , Células Madin Darby de Rim Canino , Fator 3 de Transcrição de Octâmero/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Tirfostinas/farmacologia
8.
Eur J Cancer ; 106: 133-143, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30528798

RESUMO

BACKGROUND: Both circulating tumour cell (CTC) and total circulating cell-free DNA (ccfDNA) predict cancer patient prognosis. However, no study has explored the prognostic value of the combined use of CTC and ccfDNA. We aimed to investigate individual and joint effects of CTC and ccfDNA on clinical outcomes of metastatic breast cancer (MBC) patients. METHODS: We collected 227 blood samples from 117 MBC patients. CTCs were enumerated using the CellSearch System. ccfDNAs were quantified by quantitative real-time polymerase chain reaction and Qubit fluorometer. The individual and joint effects of CTC and ccfDNA levels on patient progression-free survival (PFS) and overall survival (OS) were analysed using Cox proportional hazards models. RESULTS: Compared to patients with <5 CTCs, patients with ≥5 CTCs had a 2.58-fold increased risk of progression and 3.63-fold increased risk of death. High level of ccfDNA was associated with a 2.05-fold increased risk of progression and 3.56-fold increased risk of death. These associations remained significant after adjusting for other important clinical covariates and CTC/ccfDNA levels. CTC and ccfDNA levels had a joint effect on patient outcomes. Compared to patients with low levels of both CTC and ccfDNA, those with high levels of both markers exhibited a >17-fold increased death risk (P < 0.001). Moreover, longitudinal analysis of 132 samples from 22 patients suggested that the inconsistency between CTC level and outcome in some patients could possibly be explained by ccfDNA level. CONCLUSIONS: CTC and total ccfDNA levels were individually and jointly associated with PFS and OS in MBC patients.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , DNA Tumoral Circulante/genética , Células Neoplásicas Circulantes/patologia , Adulto , Idoso , Neoplasias da Mama/sangue , Neoplasias da Mama/mortalidade , Contagem de Células , DNA Tumoral Circulante/sangue , Progressão da Doença , Feminino , Humanos , Biópsia Líquida , Pessoa de Meia-Idade , Metástase Neoplásica , Valor Preditivo dos Testes , Intervalo Livre de Progressão , Reação em Cadeia da Polimerase em Tempo Real , Medição de Risco , Fatores de Risco , Fatores de Tempo
9.
Cancer Discov ; 6(1): 45-58, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26546296

RESUMO

UNLABELLED: An unbiased genome-scale screen for unmutated genes that drive cancer growth when overexpressed identified methyl cytosine-guanine dinucleotide (CpG) binding protein 2 (MECP2) as a novel oncogene. MECP2 resides in a region of the X-chromosome that is significantly amplified across 18% of cancers, and many cancer cell lines have amplified, overexpressed MECP2 and are dependent on MECP2 expression for growth. MECP2 copy-number gain and RAS family member alterations are mutually exclusive in several cancer types. The MECP2 splicing isoforms activate the major growth factor pathways targeted by activated RAS, the MAPK and PI3K pathways. MECP2 rescued the growth of a KRAS(G12C)-addicted cell line after KRAS downregulation, and activated KRAS rescues the growth of an MECP2-addicted cell line after MECP2 downregulation. MECP2 binding to the epigenetic modification 5-hydroxymethylcytosine is required for efficient transformation. These observations suggest that MECP2 is a commonly amplified oncogene with an unusual epigenetic mode of action. SIGNIFICANCE: MECP2 is a commonly amplified oncogene in human malignancies with a unique epigenetic mechanism of action. Cancer Discov; 6(1); 45-58. ©2015 AACR.This article is highlighted in the In This Issue feature, p. 1.


Assuntos
Citosina/análogos & derivados , Amplificação de Genes , Proteína 2 de Ligação a Metil-CpG/genética , Neoplasias/genética , Proteínas ras/genética , 5-Metilcitosina/análogos & derivados , Processamento Alternativo , Animais , Linhagem Celular Tumoral , Citosina/metabolismo , Epigênese Genética , Humanos , Proteína 2 de Ligação a Metil-CpG/metabolismo , Camundongos , Transplante de Neoplasias , Isoformas de Proteínas/metabolismo , Transdução de Sinais
11.
Nutr Metab (Lond) ; 9(1): 109, 2012 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-23216800

RESUMO

BACKGROUND: Leptin-deficient ob/ob mice exhibit adipocyte hypertrophy and hyperplasia as well as elevated adipose tissue and systemic inflammation. Multipotent stem cells isolated from adult adipose tissue can differentiate into adipocytes ex vivo and thereby contribute toward increased adipocyte cell numbers, obesity, and inflamm ation. Currently, information is lacking regarding regulation of adipose stem cell numbers as well as leptin-induced inflammation and its signaling pathway in ob/ob mice. METHODS: Using leptin deficient ob/ob mice, we investigated whether leptin injection into ob/ob mice increases adipose stem cell numbers and adipose tissue inflammatory marker MCP-1 mRNA and secretion levels. We also determined leptin mediated signaling pathways in the adipose stem cells. RESULTS: We report here that adipose stem cell number is significantly increased following leptin injection in ob/ob mice and with treatment of isolated stem cells with leptin in vitro. Leptin also up-regulated MCP-1 secretion in a dose- and time-dependent manner. We further showed that increased MCP-1 mRNA levels were due to increased phosphorylation of Signal Transducer and Activator of Transcription 3 (STAT3) Ser727 but not STAT3 Tyr705 phosphorylation, suggesting differential regulation of MCP-1 gene expression under basal and leptin-stimulated conditions in adipose stem cells. CONCLUSIONS: Taken together, these studies demonstrate that leptin increases adipose stem cell number and differentially activates STAT3 protein resulting in up-regulation of MCP-1 gene expression. Further studies of mechanisms mediating adipose stem cell hyperplasia and leptin signaling in obesity are warranted and may help identify novel anti-obesity target strategies.

12.
Tissue Eng Part A ; 14(6): 1007-15, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19230125

RESUMO

This study is the first documentation of the isolation and extensive characterization of mesenchymal stem cells from canine adipose tissue. Methods previously used by our group to isolate and differentiate human adipose-derived mesenchymal stem cells (hAD-MSCs) have been modified and optimized for derivation of similar cells from canine adipose tissues. The canine adipose tissue-derived mesenchymal stem cells (cAD-MSCs) showed lower proliferation ability and were refractory to osteogenic and adipogenic differentiation under conditions employed to differentiate hAD-MSCs. The differentiation of cAD-MSCs into osteoblasts and adipocytes was effectively achieved under modified conditions, by using laminin-coated plates and peroxisome proliferative activated receptor, gamma (PPARgamma) ligands, respectively. The formation of micromass was sufficient to induce chondrogenesis, unlike hAD-MSCs, which require transforming growth factor beta (TGF-beta). These cells displayed anchorage-independent growth in soft agar, and their colony-forming efficiency in plastic was comparable with human counterparts. The cAD-MSCs expressed genes associated with pluripotency, while their differentiated progeny expressed appropriate lineage-specific genes. The optimization of growth and differentiation of cAD-MSCs should facilitate future stem cell-based reparative and regenerative studies in dogs. The dog is a promising biomedical model that is suitable for evaluation of novel therapies such as those employing stem cells in experimental and in spontaneous disease settings.


Assuntos
Tecido Adiposo/citologia , Separação Celular/métodos , Células-Tronco Mesenquimais/citologia , Animais , Biomarcadores/metabolismo , Adesão Celular , Células Cultivadas , Senescência Celular , Condrogênese , Meios de Cultura , Cães , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Fenótipo , Plásticos
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