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1.
Crit Care Med ; 50(4): 624-632, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34582412

RESUMO

OBJECTIVES: Coronavirus disease 2019 has been reported to be a prothrombotic condition; however, multicenter data comparing this with other viral pneumonias in those requiring extracorporeal membrane oxygenation are lacking. We conducted a multicenter study using whole-body CT to examine the prevalence, severity, and nature of vascular complications in coronavirus disease 2019 in comparison with patients with other viral pneumonias. DESIGN: We analyzed whole-body CT scans for the presence of vascular thrombosis (defined as pulmonary artery thrombus, venous thrombus, systemic arterial thrombus, or end-organ infarct). The severity, distribution, and morphology of pulmonary artery thrombus were characterized. Competing risk cumulative incidence analysis was used to compare survival with discharge. SETTING: Three centers of the English national extracorporeal membrane oxygenation service. PATIENTS: Consecutive patients admitted with either coronavirus disease 2019 or noncoronavirus disease 2019 viral pneumonia admitted from January 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: One-hundred thirty-six patients (45.2 ± 10.6 yr old, 39/146 [27%] female) requiring extracorporeal membrane oxygenation support underwent whole-body CT scans at admission. Of these, 86 had coronavirus disease 2019 pneumonia, and 50 had noncoronavirus disease 2019 viral pneumonia. Vascular thrombosis was seen more often in patients with coronavirus disease 2019 (odds ratio, 12.9 [95% CI 4.5-36.8]). In those with coronavirus disease 2019, 57 (73%) demonstrated pulmonary artery thrombus or pulmonary perfusion defects. Eighty-two percent of thrombus exhibited emboli-like morphology. The location of pulmonary artery thrombus and parenchymal perfusion defects was only concordant in 30% of cases. The risk of mortality was higher in those with coronavirus disease 2019 compared with noncoronavirus disease 2019 pneumonia (χ2 = 3.94; p = 0.047). Mortality was no different in coronavirus disease 2019 patients with or without vascular thrombosis (χ2 = 0.44; p = 0.51). CONCLUSIONS: In patients who received extracorporeal membrane oxygenation, coronavirus disease 2019 is associated with a higher prevalence of vascular thrombosis compared with noncoronavirus disease viral pneumonias. The pattern of pulmonary vascular changes suggests concurrent embolic disease and small vessel disease. Despite this, vascular thrombosis was not linked to poorer short-term prognosis in those with coronavirus disease 2019.


Assuntos
COVID-19/complicações , Oxigenação por Membrana Extracorpórea , Pneumonia Viral/complicações , Trombose/etiologia , Adulto , COVID-19/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/terapia , Prognóstico , Trombose/diagnóstico por imagem , Tomografia Computadorizada por Raios X
2.
Sensors (Basel) ; 20(12)2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32630509

RESUMO

Electrowetting on dielectric-based digital microfluidic platforms (EWOD-DMF) have a potential to impact point-of-care diagnostics. Conventionally, EWOD-DMF platforms are manufactured in cleanrooms by expert technicians using costly and time consuming micro-nanofabrication processes such as optical lithography, depositions and etching. However, such high-end microfabrication facilities are extremely challenging to establish in resource-poor and low-income countries, due to their high capital investment and operating costs. This makes the fabrication of EWOD-DMF platforms extremely challenging in low-income countries, where such platforms are most needed for many applications such as point-of-care testing applications. To address this challenge, we present a low-cost and simple fabrication procedure for EWOD-DMF electrode arrays, which can be performed anywhere with a commercial office inkjet printer without the need of expensive cleanroom facilities. We demonstrate the utility of our platform to move and mix droplets of different reagents and physiologically conductive buffers, thereby showing its capability to potentially perform a variety of biochemical assays. By combining our low-cost, inkjet-printed EWOD-DMF platform with smartphone imaging technology and a compact control system for droplet manipulation, we also demonstrate a portable and hand-held device which can be programmed to potentially perform a variety of biochemical assays.


Assuntos
Eletroumectação , Microfluídica , Condutividade Elétrica , Eletrodos , Impressão
3.
Anal Chem ; 91(23): 14927-14935, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31710202

RESUMO

Cancer drug resistance mechanisms such as tumor heterogeneity and adaptable feedback loops are prevalent issues facing cancer therapy development. Drug resistance can be unique to a cancer type and, most importantly, to each individual cancer patient. Consequently, testing different dosages and therapeutics directly on each individual patient sample (i.e., tumor and cancer cells) has compelling advantages compared to large scale in vitro drug testing and is a step toward personalized drug selection and effective treatment development. Recently, microfluidic-based chemo-sensitivity assays on patient biopsies have been proposed. Despite their novelty, these platforms usually rely on optical labels, optical equipment, or complex microfabricated channel geometries and structures. In this work, we proposed a novel lab on a chip platform capable of real-time and continuous screening of drug efficacy on (cancer) cell subpopulations without the need of labels or bulky readout optical equipment. In this platform, several label-free and rapid techniques have been implemented for the precise capturing of cells of interest in parallel with the real-time measurement and characterization of the effectiveness of candidate therapeutic agents. To demonstrate the utility of the platform, the effect of an apoptotic inducer, topoisomerase I inhibitor, 7-ethyl-10-hydrocamptothecin (SN38) on human colorectal carcinoma cancer cells (HCT 116) was used as a study model. Additionally, electrical results were optically verified to examine the continuous measurements of the biological mechanisms, specifically, apoptosis and necrosis, during therapeutic agent characterizations. The proposed device is a versatile platform which can also be easily redesigned for the automated and arrayed analysis of cell-drug interaction down to the single cell level. Our platform is another step toward enabling the personalized screening of drug efficacy on individual patients' samples that potentially leads to a better understanding of drug resistance and the optimization of patients' treatments.


Assuntos
DNA Topoisomerases Tipo I/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Irinotecano/farmacologia , Dispositivos Lab-On-A-Chip , Inibidores da Topoisomerase I/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , DNA Topoisomerases Tipo I/metabolismo , Monitoramento de Medicamentos/métodos , Impedância Elétrica , Células HCT116 , Humanos , Modelos Biológicos , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/genética , Neoplasias/patologia , Medicina de Precisão
4.
Mod Pathol ; 30(1): 60-68, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27713424

RESUMO

Outcomes for melanoma patients vary within cancer stage. Prognostic biomarkers are potential adjuncts to provide more precise prognostic information. Simple, low-cost biomarker assays, such as those based on immunohistochemistry, have strong translational potential. 5-hydroxymethylcytosine (5 hmC) shows prognostic potential in melanoma but prior studies were small. We, therefore, analysed 5 hmC in a retrospective cohort to provide external validation of its prognostic value. Two hundred primary melanomas were evaluated for 5 hmC expression using immunohistochemistry. The primary objective was to assess the effect on overall survival while controlling for important confounders. Univariable and multivariable analyses were performed. REMARK guidelines were followed. The 5 hmC immunohistochemistry scoring showed very strong inter-observer agreement (ICC 0.88) and expression was significantly related to age, site, Breslow thickness, ulceration, mitotic rate, and stage. Kaplan-Meier analysis showed 5 hmC was associated with metastasis-free, melanoma-specific, and overall survival, P<0.0001 for each. In univariable Cox proportional hazards models, 5 hmC hazard ratios were significant and remained so in a multivariable model. A two-step cox model was created using stage and 5 hmC, as stage is the gold standard for clinical practice. The addition of 5 hmC produced significant improvement in the model and 5 hmC and stage were independent significant predictors. This is the largest study of the prognostic value of 5 hmC immunohistochemistry in melanoma. The 5 hmC scoring was easily and reproducibly performed and it was an independent predictor of metastasis-free survival, melanoma-specific survival, and overall survival. This work supports further development of 5 hmC as a prognostic biomarker and suggests that it could add more precision to American Joint Committee on Cancer staging.


Assuntos
5-Metilcitosina/análogos & derivados , Melanoma/metabolismo , Neoplasias Cutâneas/metabolismo , Pele/metabolismo , 5-Metilcitosina/metabolismo , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Pele/patologia , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Taxa de Sobrevida
5.
ACS Biomater Sci Eng ; 10(6): 3896-3908, 2024 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-38748191

RESUMO

Microfluidic spinning is emerging as a useful technique in the fabrication of alginate fibers, enabling applications in drug screening, disease modeling, and disease diagnostics. In this paper, by capitalizing on the benefits of aqueous two-phase systems (ATPS) to produce diverse alginate fiber forms, we introduce an ATPS-Spinning platform (ATPSpin). This ATPS-enabled method efficiently circumvents the rapid clogging challenges inherent to traditional fiber production techniques by regulating the interaction between alginate and cross-linking agents like Ba2+ ions. By varying system parameters under the guidance of a regime map, our system produces several fiber forms─solid, hollow, and droplet-filled─consistently and reproducibly from a single device. We demonstrate that the resulting alginate fibers possess distinct features, including biocompatibility. We also encapsulate HEK293 cells in the microfibers as a proof-of-concept that this versatile microfluidic fiber generation platform may have utility in tissue engineering and regenerative medicine applications.


Assuntos
Alginatos , Alginatos/química , Humanos , Células HEK293 , Microfluídica/métodos , Microfluídica/instrumentação , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química
6.
Cureus ; 15(10): e46651, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37936999

RESUMO

BACKGROUND: Maintenance hemodialysis (MHD) prolongs the life of patients with end-stage chronic kidney disease (CKD), but this process can change their lifestyle, affecting their quality of life (QoL). Patients with MHD require their caregivers' assistance in daily management and repeated hospital visitation. This places a burden on caregivers affecting their QoL. Both patient and caregiver form a unit during the caregiving process. This study aims to compare and correlate the QoL of patients with CKD under MHD with their caregivers, considering their common familial and socioeconomic backgrounds. METHODOLOGY: This is a cross-sectional, comparative study in the Hemodialysis Unit of Patan Academy of Health Sciences (PAHS), Lalitpur, Nepal. Patients aged >14 years with CKD under MHD and caregivers staying with the patient at their resident place for a minimum of two months were included in the study. QoL of patients with CKD under MHD was compared with caregivers under different domains of the physical component summary (PCS) and mental component summary (MCS) scores using an SF-36 (Short form-36) health survey questionnaire. Data was collected and entered in Microsoft Excel 2010/Epi info version 7.2 and analyzed. RESULTS: The overall QoL of caregivers was better than CKD patients under MHD in terms of both PCS score (48.13 vs. 35.36) and MCS score (48.11 vs. 43.25) and was statistically significant (p-value: <0.001) in both scores. The patient's QoL was not significantly correlated with the caregiver's PCS score (p-value: 0.635). Still, there was a significant correlation between QoL and MCS scores (p-value: 0.006). Similarly, caregivers had better QoL than CKD patients under MHD under all eight domains, which was statistically significant. No significant correlation was found between the frequency and duration of MHD with PCS and MCS scores of both patient and caregiver. CONCLUSION: Overall, the physical and mental QoL of the caregiver was better than CKD patients under MHD. Further studies need to be conducted to assess the QoL of both groups compared to the healthy population to address the issue of hemodialysis patients and their caregivers.

7.
Pharmaceutics ; 14(11)2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36432707

RESUMO

Targeted drug and gene delivery using ultrasound and microbubbles (USMB) has the potential to treat several diseases. In vitro investigation of USMB-mediated delivery is of prime importance prior to in vivo studies because it is cost-efficient and allows for the rapid optimization of experimental parameters. Most in vitro USMB studies are carried out with non-clinical, research-grade ultrasound systems, which are not approved for clinical use and are difficult to replicate by other labs. A standardized, low-cost, and easy-to-use in vitro experimental setup using a clinical ultrasound system would facilitate the eventual translation of the technology to the bedside. In this paper, we report a modular 3D-printed experimental setup using a clinical ultrasound transducer that can be used to study USMB-mediated drug delivery. We demonstrate its utility for optimizing various cargo delivery parameters in the HEK293 cell line, as well as for the CMT167 lung carcinoma cell line, using dextran as a model drug. We found that the proportion of dextran-positive cells increases with increasing mechanical index and ultrasound treatment time and decreases with increasing pulse interval (PI). We also observed that dextran delivery is most efficient for a narrow range of microbubble concentrations.

8.
Biomedicines ; 9(7)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34356867

RESUMO

Acute respiratory distress syndrome (ARDS) is characterized by increased permeability of the alveolar-capillary membrane, a thin barrier composed of adjacent monolayers of alveolar epithelial and lung microvascular endothelial cells. This results in pulmonary edema and severe hypoxemia and is a common cause of death after both viral (e.g., SARS-CoV-2) and bacterial pneumonia. The involvement of the lung in ARDS is notoriously heterogeneous, with consolidated and edematous lung abutting aerated, less injured regions. This makes treatment difficult, as most therapeutic approaches preferentially affect the normal lung regions or are distributed indiscriminately to other organs. In this review, we describe the use of thoracic ultrasound and microbubbles (USMB) to deliver therapeutic cargo (drugs, genes) preferentially to severely injured areas of the lung and in particular to the lung endothelium. While USMB has been explored in other organs, it has been under-appreciated in the treatment of lung injury since ultrasound energy is scattered by air. However, this limitation can be harnessed to direct therapy specifically to severely injured lungs. We explore the cellular mechanisms governing USMB and describe various permutations of cargo administration. Lastly, we discuss both the challenges and potential opportunities presented by USMB in the lung as a tool for both therapy and research.

9.
Adv Biosyst ; 4(11): e2000160, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33025770

RESUMO

Cancers are a complex conglomerate of heterogeneous cell populations with varying genotypes and phenotypes. The intercellular heterogeneity within the same tumor and intratumor heterogeneity within various tumors are the leading causes of resistance to cancer therapies and varied outcomes in different patients. Therefore, performing single-cell analysis is essential to identify and classify cancer cell types and study cellular heterogeneity. Here, the development of a machine learning-assisted nanoparticle-printed biochip for single-cell analysis is reported. The biochip is integrated by combining powerful machine learning techniques with easily accessible inkjet printing and microfluidics technology. The biochip is easily prototype-able, miniaturized, and cost-effective, potentially capable of differentiating a variety of cell types in a label-free manner. n-feature classifiers are established and their performance metrics are evaluated. The biochip's utility to discriminate noncancerous cells from cancerous cells at the single-cell level is demonstrated. The biochip's utility in classifying cancer sub-type cells is also demonstrated. It is envisioned that such a chip has potential applications in single-cell studies, tumor heterogeneity studies, and perhaps in point-of-care cancer diagnostics-especially in developing countries where the cost, limited infrastructures, and limited access to medical technologies are of the utmost importance.


Assuntos
Dispositivos Lab-On-A-Chip , Aprendizado de Máquina , Nanopartículas/química , Análise de Célula Única/métodos , Bioimpressão , Linhagem Celular Tumoral , Humanos
10.
FEBS J ; 285(16): 3097-3113, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29971953

RESUMO

A large body of data demonstrates that interferon regulatory factor 5 (IRF5) and nuclear factor kappa B (NF-κB) are the two major transcription factors in classically activated macrophages responsible for the transcriptional control of proinflammatory genes. Although recent evidence suggests that IRF5 interacts with certain members of the nuclear factor kappa B pathway, the extent of cooperation and its implications in disease are ambiguous. Since both pathways are known for their strong contributions in TLR8 signaling we used the human monocytic cell line THP-1.Dual, featuring gene reporters for NF-κB and IRFs, to simultaneously study the roles of IRF5 and the NF-κB subunit p65 in TLR8-mediated gene reporter activities. Furthermore, we profiled from these cells the proinflammatory cytokines involved in the differentiation of TH1 and TH17 cells. After ablation of IRF5 and/or p65 we activated the resultant cells with the TLR8 agonists R848 or the psoriasis-associated antimicrobial peptide LL-37 complexed with ssRNA and demonstrate that IRF5 deficiency drastically impairs the secretion of IL-1ß, IL-6, IL-12, IL-23 and TNFα. In contrast, the lack of p65 impaired only IL-6, IL-12, and IL-23 secretion. Furthermore, we discovered that upon TLR8 stimulation, IRF5 but not NF-κB signaling is essential to provide a cytokine milieu supporting TH1 responses. Additionally, we demonstrate that IRF5 and NF-κB cooperate to provide a cytokine milieu supporting TH17 responses. Therefore, the distinct role of IRF5 in the intricate signaling network downstream of TLR8 may open new treatment options interfering with but not disrupting NF-κB signaling in human diseases.


Assuntos
Inflamação/metabolismo , Fatores Reguladores de Interferon/metabolismo , NF-kappa B/metabolismo , Células Th1/imunologia , Células Th17/imunologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Sistemas CRISPR-Cas , Linhagem Celular , Citocinas/metabolismo , Técnicas de Inativação de Genes , Genes Reporter , Humanos , Imidazóis/farmacologia , Fatores Reguladores de Interferon/genética , NF-kappa B/genética , Elementos de Resposta , Transdução de Sinais , Células Th1/efeitos dos fármacos , Células Th1/metabolismo , Células Th17/efeitos dos fármacos , Células Th17/metabolismo , Receptor 8 Toll-Like/agonistas , Receptor 8 Toll-Like/imunologia , Receptor 8 Toll-Like/metabolismo , Catelicidinas
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