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1.
Iran J Biotechnol ; 20(3): e3036, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36381284

RESUMO

Background: Autolysate products from yeast origin are very interesting for food, feed, cosmetic, pharmaceutical, and fermentation industries. The lysis process greatly influences the quality and efficiency of the final autolysates. Objectives: Here, we have compared four lysis methods based on autolysis, plasmolysis (with ethanol 1.5% (v/v) and coconut fatty acids 1% (w/w)) and hydrolysis (with alkaline protease 0.4 % (v/w)) on degrading the baker's yeast Saccharomyces cerevisiae. Materials and Methods: The efficiency of processes was evaluated according to the recovered solid and protein contents, release of intracellular materials, cell viability, microscopy imaging, degree of hydrolysis and electrophoresis studies. Results: Results showed that the increased recovered solids and proteins, as well as a higher degree of hydrolysis (DH) were obtained for the enzymatic hydrolyzed cells using alkaline protease. SDS-PAGE analysis also confirmed the results. Further, functionality of the final products by agglutination test showed that the hydrolyzed cells could effectively bind pathogenic bacteria compared to the other cell lysates. Conclusions: In conclusion, this work provides adequate evidence for efficiency of alkaline protease for producing the nutritional cell lysates from baker's S. cerevisiae used in food, feed, cosmetic, and pharmaceutical applications. Moreover, this was the first report on using coconut fatty acids and alkaline protease in lysis of baker's yeast.

2.
Cancer Med ; 11(7): 1630-1645, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35224879

RESUMO

BACKGROUND: Cancer diagnostic probe (CDP) had been developed to detect involved breast cavity side margins in real-time (Miripour et al. Bioeng Transl Med. e10236.). Here, we presented the results of the in vivo human model CDP studies on non-neoadjuvant cases. METHODS: This study is a prospective, blind comparison to a gold standard, and the medical group recruited patients. CDP and frozen data were achieved before the permanent pathology experiment. The main outcome of the study is surgical margin status. From November 2018 to April 2020, 202 patients were registered, and 188 were assigned for the study. Breast-conserving surgery at any age or gender, re-surgery due to re-currency, or involved margins are acceptable. Patients must be non-neoadjuvant. The reliability of CDP scoring had been evaluated by the pathology of the scored IMs. Then, three models of the study were designed to compare CDP with the frozen sections. Receiver operating characteristic (ROC) curves and AUC were measured based on the permanent postoperative pathology gold standard. RESULTS: A matched clinical diagnostic categorization between the pathological results of the tested IMs and response peaks of CDP on 113 cases, was reported (sensitivity = 97%, specificity = 89.3%, accuracy = 92%, positive predictive value (PPV) = 84.2%, and negative predictive value (NPV) = 98%). Study A showed the independent ability of CDP for IM scoring (sensitivity = 80%, specificity = 90%, accuracy = 90%, PPV = 22.2%, and NPV = 99.2%). Study B showed the complementary role of CDP to cover the missed lesions of frozen sections (sensitivity = 93.8%, specificity = 91%, accuracy = 91%, PPV = 55.6%, and NPV = 99.2%). Study C showed the ability of CDP in helping the pathologist to reduce his/her frozen miss judgment (specificity = 92%, accuracy = 93%, PPV = 42.1%, and NPV = 100%). Results were reported based on the post-surgical permanent pathology gold standard. CONCLUSION: CDP scoring ability in intra-operative margin detection was verified on non-neoadjuvant breast cancer patients. Non-invasive real-time diagnosis of IMs with pathological values may make CDP a distinct tool with handheld equipment to increase the prognosis of breast cancer patients.


Assuntos
Neoplasias da Mama , Margens de Excisão , Feminino , Humanos , Masculino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Glicólise , Hipóxia , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Med Phys ; 49(4): 2746-2760, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35107181

RESUMO

PURPOSE: Evaluating a real-time complementary bioelectrical diagnostic device based on electrical impedance spectroscopy (EIS) for improving breast imaging-reporting and data system (BI-RADS) scoring accuracy, especially in high-risk or borderline breast diseases. The primary purpose is to characterize breast tumors based on their dielectric properties. Early detection of high-risk lesions and increasing the accuracy of tumor sampling and pathological diagnosis are secondary objectives of the study. METHODS: The tumor detection probe (TDP) was first applied to the mouse model for electrical safety evaluations by electrical current measurement. Then it was utilized for characterization of 138 human palpable breast lesions that were to undergo core needle biopsy (CNB), vacuum-assisted biopsy (VAB), or fine needle aspiration (FNA) on the surgeon's requests. Impedance phase slope (IPS) in frequency ranges of 100- 500 kHz and impedance magnitude in f = 1 kHz were extracted as the classification parameters. Consistency of radiological and pathological declarations for the excisional recommendation was then compared with the IPS values. RESULTS: Considering pathological results as the gold standard, meaningful correlations between IPS and pathophysiological status of lesions recommended for excision (such as atypical ductal hyperplasia, papillary lesions, complex sclerosing adenosis, and fibroadenoma) were observed (p < 0.0001). These pathophysiological properties may include cell size, membrane permeability, packing density, adenosis, cytoplasm structure, etc. Benign breast lesions showed IPS values greater than 0, while high-risk proliferative, precancerous, or cancerous lesions had negative IPS values. Statistical analysis showed 95% sensitivity with area under the curve (AUC) equal to 0.92. CONCLUSION: Borderline breast diseases and high-risk lesions that should be excised according to standard guidelines can be diagnosed with TDP before any sampling process. It is an important outcome for high-risk lesions that are radiologically underestimated to BI-RADS3, specifically in younger patients with dense breast masses that present challenges in mammographic and sonographic evaluations. Also, the lowest IPS value detects the most pathologic portions of the tumor for increasing sampling accuracy in large tumors. SIGNIFICANCE: Precise detection of high-risk breast masses, which may be declared BI-RADS3 instead of BI-RADS4a.


Assuntos
Doenças Mamárias , Neoplasias da Mama , Animais , Densidade da Mama , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Proteínas de Ligação a DNA , Espectroscopia Dielétrica , Feminino , Humanos , Mamografia , Camundongos , Estudos Retrospectivos
4.
Bioeng Transl Med ; 7(1): e10236, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35079624

RESUMO

For most people, the first step in treatment is to take out the tumor (surgery), so precise and fast diagnosis of any sign of high-risk and neoplastic cells, especially in surgical cavity margins, is significant. The frozen pathology method is the conventional standard of intraoperative diagnosis, but the low number of slides prepared from non-fixed tissues prevents us from achieving a perfect diagnosis. Although many improvements in intraoperative margin detection were achieved, still real-time detection of neoplastic lesions is crucial to improving diagnostic quality. Functionalized carbon nanotubes grown on the electrode needles lively and selectively determine the H2O2 released from cancer/atypical cells through reverse Warburg effect and hypoxia assisted glycolysis pathways in a quantitative electrochemical manner. The study was carried out on cell lines, 57 in vivo mice models with breast cancer, and 258 fresh in vitro samples of breast cancer tumors. A real-time electrotechnical system, named cancer diagnostic probe (CDP) (US Patent Pub. No.: US 2018/02991 A1, US 2021/0007638 A1, and US 2021/0022650 A1 [publications], and US 10,786,188 B1 [granted]), has been developed to find pre-neoplastic/neoplastic cells in vivo in a quantitative electrochemical manner by tracing hypoxia glycolysis byproducts. Matched pathological evaluations with response peaks of CDP were found based on the presence of neoplasia (from atypia to invasive carcinoma) in live breast tissues. The ability of CDP to find neoplastic lesions in mice models in vivo and fresh breast tumors in vitro was verified with sensitivity and specificity of 95% and 97%, respectively. The system may help a surgeon assistant system for usage in the operating room after passing many trials and standard examinations in the future.

5.
Nanoscale ; 12(43): 22129-22139, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33119020

RESUMO

Herein, we present a new design on the Single Needle Electrochemical Therapy (SNEChT) method by introducing some major improvements, including a nanoporous platinum electrode, tunable in situ anode size that depends on the width and location of the tumor, and the capability of measuring the efficacy of therapy based in intra-therapeutic impedance recording by the same EChT needle. It could have significant implications in optimizing EChT operative conditions. The nanoporous Pt electrode increased the interactive surface with a tumor, and produced a higher amount of current with lower stimulating DC voltage. The tunable anode size prevents the over-acidification of treated or non-desired lesions. Hence, this feature reduced the over distribution of tissue. Monitoring the impedance during the therapy clearly informs us about the local destruction of the tumor in each location. Thus, we can be informed about the threshold of tissue acidosis with the lowest electrical stimulation. The insertion of one needle with a tunable anode length for both precise therapy and impedance-based intra-therapeutic monitoring will shed new light on the applications of EChT.


Assuntos
Terapia por Estimulação Elétrica , Nanoporos , Neoplasias , Impedância Elétrica , Eletroquímica , Eletrodos , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Platina
6.
Analyst ; 145(23): 7636-7645, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-32955530

RESUMO

Separation of cancerous from normal cells is of broad importance in a large number of cancer diagnosis and treatment methods. One of the most important factors to designate and specify different cells is to study their dielectric and electric cell membrane characteristics. In this research, a label-free cytological slide chip (CSC) is designed and fabricated based on AC electric field stimulation of breast cell lines and blood cells at low frequencies (1 kHz-200 kHz). The AC-CSC traps cells based on their dielectric polarization functions which is distinct between different phenotypes of breast cells and blood cells. We learned that by using AC electric fields, each breast cell line shows a capturing response to a specific range of frequencies. The progression in cancer phenotypes decreases the cell's polarizability. Hence, characteristic frequency responses were achieved for these cells. In this study, thermal potential and electrolysis which were the main bottle neck problems in DC applied fields were completely solved. The AC-CSC could be used in CTC separation from leukocytes, a test performed based on a compound with 1% cancer cells in white blood cells (1% MDA-MB-231 : 99% WBC) which results in 90% capturing efficiency of cancer cells. Frequency dependent capturing brings so much hope that smart slides will be useful at the clinical stage in the near future.


Assuntos
Células Neoplásicas Circulantes , Células Sanguíneas , Linhagem Celular Tumoral , Separação Celular , Humanos , Leucócitos , Fenótipo
7.
Biosens Bioelectron ; 165: 112421, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32729539

RESUMO

In this paper, freshly (non-fixed) dissected tissues obtained from breast cancer surgery were impedimetrically and pathologically scanned, analyzed, and probable electro-pathological mutual matching was investigated. A new electrical model was proposed for pathological scores of breast lesions based on the theory of electric current dispersion by different types of biological tissues. This integrated handheld bioimpedance sensor named EPA would score the clearance or malignancy involvement of dissected tumor margins by introducing two crucial classification parameters named Z1kHz and IPS (impedance phase slope in the frequency ranges of 100-500 kHz). EPA benefits from a precise signal recording and analysis method which leads to the detection of the presence of even about 5% distribution of premalignant cells among healthy breast tissue. EPA can be clinically used by pathologists, as a complementary device, for real-time diagnosis of suspicious margins of dissected tumors to declare more precise intraoperative diagnosis by scanning all around the dissected tissues. Each data sampling and analysis covers 2 mm of the surface in less than 5 s. Measurements on about 313 human breast tumor margins showed more than 90% accuracy and near 93% specificity for EPA as an independent diagnostic tool.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Mama , Neoplasias da Mama/diagnóstico , Espectroscopia Dielétrica , Impedância Elétrica , Humanos
8.
Biosens Bioelectron ; 165: 112435, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32729548

RESUMO

COVID-19 is the shocking viral pandemics of this year which affected the health, economy, communications, and all aspects of social activities all over the world. Early diagnosis of this viral disease is very important since it can prevent lots of mortalities and care consumption. The functional similarities between COVID-19 and COVID-2 in inducing acute respiratory syndrome lightened our mind to find a diagnostic mechanism based on early traces of mitochondrial ROS overproduction as lung cells' dysfunctions induced by the virus. We designed a simple electrochemical sensor to selectively detect the intensity of ROS in the sputum sample (with a volume of less than 500 µl). Comparing the results of the sensor with clinical diagnostics of more than 140 normal and involved cases resulted in a response calibration with accuracy and sensitivity both 97%. Testing the sensor in more than 4 hospitals shed promising lights in ROS based real-time tracing of COVID-19 from the sputum sample.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas Biossensoriais/métodos , Infecções por Coronavirus/diagnóstico , Técnicas Eletroquímicas/métodos , Pneumonia Viral/diagnóstico , Espécies Reativas de Oxigênio/análise , Escarro/virologia , Adulto , Idoso , Técnicas Biossensoriais/instrumentação , COVID-19 , Infecções por Coronavirus/virologia , Diagnóstico Precoce , Técnicas Eletroquímicas/instrumentação , Desenho de Equipamento , Feminino , Humanos , Pulmão/química , Pulmão/virologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/virologia , SARS-CoV-2 , Sensibilidade e Especificidade , Escarro/química , Adulto Jovem
9.
Biosens Bioelectron ; 161: 112209, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32442106

RESUMO

An electrochemical biopsy probe was designed and fabricated to detect cancer tumors under the sonography guide without the need for any sample dissection (biopsy). The system was based on recording the hypoxic function of cancer tumors by Multi-wall carbon nanotubes (MWCNTs) sensing agents had been decorated on the tip of the needle electrodes by an electrostatic deposition method. This system named BGP successfully distinct 4T1 and MC4L2 breast tumors from normal lesions. It also diagnosed the treated tumors from vital ones. BGP as a clinically useful biosensor would detect the cancerous probability of any suspicious breast mass without any sample excision. Also, it can present a profile from neoplastic states of different regions of a tumor. This ability would make ensure for the radiologist to do biopsy or not, especially in the cases which are suspicious between BIRADS III and IVa. This would not only shed new light in detecting breast cancer tumors without biopsy (applied in radiological BIRADS classifications) but also evaluate the therapeutic effects on cancer tumors after chemotherapy/radiotherapy therapies without complicated and expensive scanning.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama/diagnóstico , Mama/diagnóstico por imagem , Nanotubos de Carbono/química , Biópsia com Agulha de Grande Calibre/métodos , Mama/patologia , Neoplasias da Mama/patologia , Feminino , Humanos , Radiologia Intervencionista , Ultrassonografia
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