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Journal of Sensor Technology 2023年第4期13卷 59-68页

作者： Srivatsa Aithal Sujasha Gupta Khanh Duong Ankit Kumar Nathan Ho Dongdong Liu John Warden David Huy Ho hememics biotechnologies inc Gaithersburg USA

Exposure to toxins can lead to a wide range of adverse health effects, including respiratory problems, neurological disorders, cancer, and reproductive issues. Toxins can come from various sources, such as industrial waste, agricultural runoff, and household chemicals. Therefore, detecting and monitoring toxins in the environment is crucial for protecting human health and the environment. This study aimed to evaluate the performance of hememics biosensor system in detecting environmental toxins such as Ricin and Staphylococcal enterotoxin B (SEB) in mixed matrixes. When Ricin and SEB are spiked into soil, chopped lettuce, tap water, milk and serum, the biosensor was able to detect these toxins, without sample processing, at a level of detection comparable to lab testing with high sensitivity and specificity. Furthermore, hememics biosensor system is designed to be network-enabled, which means that results can be transmitted to relevant agencies for quick decisions. This feature is crucial in cases where quick action is needed to prevent further contamination or exposure to harmful toxins.

关键词： Portable Biosensor Graphene Based Biochip HemChip™ Rapid Detection Field Use Networking

Transporting Mammalian Cells at Ambient Temperature:A Viable Alternative to Dry Ice

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Advances in Bioscience and Biotechnology 2017年第4期8卷 127-133页

作者： Steingrimur Stefansson Seunghyun Han Ye In Jeon David S.Chung Peter Hwang Huyen Le John L.Warden David Ho hememics biotechnologies inc RockvilleUSA Johns Hopkins University BaltimoreUSA George Washington University WashingtonDCUSA Division of Biology and Medicine Brown UniversityProvidenceUSA Thomas Jefferson High School for Science and Technology AlexandriaUSA Nauah Solutions McleanUSA

The most common method of shipping cells between institutes and companies is sending them frozen, usually treated with anti-freeze solution (most commonly DMSO because it is less toxic than many alternatives), and then packaging them in dry ice for shipment. However many countries place restrictions on dry ice shipments. An alternative to shipping frozen cell vials is to send flasks of growing cells in media. This also has problems because cells in media have limited viability and the flasks can leak. Here we report on an alternative method for shipping viable cells at ambient temperature without dry ice or in media filled flasks. In this study we report on the development and properties of HemSol?. This is an inexpensive, eco-friendly and protects cell integrity at ambient temperature while maintaining viability. We have previously shown that HemSol? protects platelet and RBC function in cold storage and circulating tumor cells up to 6 days. Therefore we wanted to know if HemSol? could also be used to transport live cells. Since HemSol? is a liquid, we experimented with encasing the cells with HemSol? and gelatin so as to prevent dry ice shipment of cells and circumvent the shipping of cells in media. We performed mock shipping experiments where cells were stored in HemSol? gel kept at room temperature on a lab benchtop and cells stored in dry ice was also kept on lab benchtop for up to 2 days. After the mock shipping period, we analyzed cells for their functions. Our results show that cells in HemSol? gel have greater than 95% viability and restored biological functions in 2 hours, whereas, cells shipped in dry ice required more than 24 hours to recover and needed media change to remove the DMSO.

关键词： HemSol^(TM) HemSol^(TM) Gel Transportation Short Term Storage Cells Shipment Dry Ice Ambient Temperature Shipment

Evaluating an enzyme multiplied immunoassay technique of a phenytoin kit on an ARCHITECT C16000

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Evaluating an enzyme multiplied immunoassay technique of a p...

Glucose-6-phosphate dehydrogenase mutant K56C/D306C/D427C with higher inhibition rate for enzyme multiplied immunoassay of Cyclosporine A

2021年中国肿瘤标志物学术大会暨第十五届肿瘤标志物青年科学家论坛

作者： Jinxiang Qi Jun Gong Beijing Strong biotechnologies Inc.

Background : Phenytoin(PTN) is one of the most commonly used drugs in epilepsy,and its special pharmacokinetics and narrow therapeutic window make it necessary to monitor the concentration of PTN in the blood to help ensure approprite ***: The objective of this study was to evaluate the performance of an enzyme multiplied immunoassay technique(EMIT) PTN kit on an ARCHITECT ***: The EMIT PTN kit was developed by Beijing Strong biotechnologies(BSBE), *** the following studies were performed on an ARCHITECT C16000 clinical chemistry ***-level controls and two serum sample pools were adopted to the precision studies according to Clinical and Laboratory Standards Institute(CLSI) EP05-A2, and the accuracy, linearity and specificity studies were evaluated according to EP15-A2, EP06-A2 and EP14-A2 ***: The repeatability, precision, spike recovery, specificity data are demonstrated in Table 1 A,1 B,1 C,1 *** linear range of the PTN kit is 2.0 to 40 μg/ml, and the linear equation is y =3.7355 x-1.8278 with R2 = 0.999.16 kinds of compounds were tested for specificity studies,15 compounds list in table 1 D caused ≤10% change in drug concentration when tested in the presence of15 μg/ml *** the compound fosphenytoin,at a level of 60 μg/ml, caused a 22.98% change when tested in the presence of 15 μg/ml ***: The EMIT PTN kit developed by BSBE has a good performance in repeatability, precision,accuracy, specificity and linearity which could be used for clinical phenytoin detection.

关键词： EMIT PTN evaluat

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Glucose-6-phosphate dehydrogenase mutant K56C/D306C/D427C wi...

Soluble Expression in Escherichia Coli and Purification of Human Carboxylesterase 1

2021年中国肿瘤标志物学术大会暨第十五届肿瘤标志物青年科学家论坛

作者： Lei Zhao Guili Wang Qifei Zhang Jun Gong Beijing Strong biotechnologies Inc.

Background: The inhibition rate is a key parameter to accurately detect the concentration of small moleculars such as Cyclosporine A(CsA) in patient sample with enzyme-multiplied immunoassay technique(EMIT). Several factors may contribute to the inhibitor rate in EMIT assay, such as the conjugation site on Glucose-6-phosphate dehydrogenase(G6 PDH), the selection of the antibody,reaction buffer composition, etc. Here we use CsA as an example to investigate the influence of conjugation sites on the inhibition ***: G6 PDH(about 55.4 KDa) mutants with one to three cysteines mutations at different sites, including K56 C, D156 C, D200 C, D259 C, D306 C, D427 C, D480 C, K56 C/D306 C, K56 C/D427 C,K56 C/D306 C/D427 C and K56 C/D306 C/D454 C were constructed. Site directed conjugation were carried out between the cysteine group from the mutants and the maleimide group from the CsA derivative. The molecular weight of the conjugate was confirmed by mass spectrometer, and the change of enzyme activity was measured by a Hitachi 7180 biochemical analyzer to evaluate the antibody inhibition rate. The inhibition rate was expressed as following:Inhibition rate= [1-G6 PDH Activity(antibody)/G6 PDH Activity(without antibody)] ×100%Results: The structure of the CsA derivative was shown in Fig. 1 A, and the molecular weight of the CsA derivative was 1424.88. According to the Fig. 1 B and Fig. 1 C, the molecular weight of the G6 PDH D427 C-CsA conjugate was 56921.67, and the K56 C/D306 C/D427 C-CsA was 59735.63, which indicated the mutants with single or triple cysteines were coupled with one and three derivatives,respectively. The inhibition rates of different G6 PDH-CsA conjugates were shown in Table 1. Among the different single mutants, the inhibition rate of D427 C-CsA was the highest(22%), D306 C-CsA the second(12%), and other sites showed little inhibition. Besides, one triple mutant,K56 C/D306 C/D427 C, exhibited the highest inhibition rate(52%), which was approximately

关键词： EMIT Cyclosporine A Inhibition rate

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Chinese Journal of Biomedical Engineering(English Edition) 2014年第1期23卷 29-37页

作者： WANG Lei TONG Jin-ying CAO Peng-rong PENG Xiao-ning YI Yin-sha LV Yuan Medical College of Hunan Normal University Changsha Yingrun biotechnologies inc.

Objective: To achieve an optimized method for soluble expression of human carboxylesterase 1(hCE-1) in escherichia coil and purification by Ni2+-NTA agarose affinity chromatography, to get improved protein yield and purity for further development of hepatocellular carcinoma(HCC) diagnosis ELISA kits. Methods: The best antigen epitopes of hCE1 were predicted by comparing secondary structure, flexible regions, hydrophilicity, antigenic index surface probability of residues. Afterwards,pET-42a(+) with a His-tag and a GST-tag was applied to form recombinant plasmid pET-42a(+)/hCE1, which facilitated purification when using Ni2+-NTA agarose affinity chromatography. Protein quality was measured by SDS-PAGE and BCA protein ***-blot identification was also performed to ensure the correct expression of hCE1protein. Results: The residues from 500 to 567 near C-terminal of hCE1 protein were considered the best epitopes which exhibited high hydrophilicity and high surface probability and relatively flexible secondary structure and low homology compared with hCE2 and hCE3. His-hCE1 500-567 fusion protein was achieved by IPTG-inducted expression with an expected mass of 42 kDa. After purification, the final product was specially identified, which reached over 95% purity and more than 10 mg/L of microbial culture. In Western blot, the purified fusion protein was recognized by anti-hCE1monoclonal antibody, along with previous sequencing validation, which demonstrated the correct preparation of soluble hCE1 protein. Conclusion: This is an efficacious and affordable strategy to generate fusion hCE1 of high quality in E coli, which facilitates preparation of hCE1 monoclonal antibody and further HCC diagnosis research.

关键词：可溶性表达大肠杆菌羧酸酯酶纯化 Western-blot Western印迹 ELISA方法单克隆抗体

Motor neuron replacement therapy for amyotrophic lateral sclerosis

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Neural Regeneration Research 2022年第8期17卷 1633-1639页

作者： Bochao Liu Mo Li Lingyan Zhang Zhiguo Chen Paul Lu Cell Therapy Center Beijing Institute of GeriatricsXuanwu HospitalCapital Medical UniversityNational Clinical Research Center for Geriatric Diseasesand Key Laboratory of Neurodegenerative DiseasesMinistry of EducationBeijingChina Center of Neural Injury and Repair Beijing Institute for Brain DisordersBeijingChina Center of Parkinson’s Disease Beijing Institute for Brain DisordersBeijingChina iXCells biotechnologies USA Inc.San DiegoCAUSA Amogene Biotech XiamenFujian ProvinceChina Veterans Administration San Diego Healthcare System San DiegoCAUSA Department of Neurosciences University of California-San DiegoLa JollaCAUSA

Amyotrophic lateral sclerosis is a motor neuron degenerative disease that is also known as Lou Gehrig’s disease in the United States,Charcot’s disease in France,and motor neuron disease in the *** loss of motor neurons causes muscle wasting,paralysis,and eventually death,which is commonly related to respiratory failure,within 3-5 years after onset of the *** there are a limited number of drugs approved for amyotrophic lateral sclerosis,they have had little success at treating the associated symptoms,and they cannot reverse the course of motor neuron ***,there is still a lack of effective treatment for this debilitating neurodegenerative *** cell therapy for amyotrophic lateral sclerosis is a very attractive strategy for both basic and clinical researchers,particularly as transplanted stem cells and stem cell-derived neural progenitor/precursor cells can protect endogenous motor neurons and directly replace the lost or dying motor *** cell therapies may also be able to re-establish the motor control of voluntary ***,we review the recent progress in the use of neural stem cells and neural progenitor cells for the treatment of amyotrophic lateral *** focus on MN progenitor cells derived from fetal central nervous system tissue,embryonic stem cells,and induced pluripotent stem *** our recent studies,we found that transplanted human induced pluripotent stem cell-derived motor neuron progenitors survive well,differentiate into motor neurons,and extend axons into the host white matter,not only in the rostrocaudal direction,but also along motor axon tracts towards the ventral roots in the immunodeficient rat spinal ***,the significant motor axonal extension after neural progenitor cell transplantation in amyotrophic lateral sclerosis models demonstrates that motor neuron replacement therapy could be a promising therapeutic strategy for amyotrophic lateral sclerosis,particularly as a variety

关键词： amyotrophic lateral sclerosis motor neuron replacement neural progenitor cells neural stem cells stem cells

Progressive loss of striatal dopamine terminals in MPTP-induced acute parkinsonism in cynomolgus monkeys using vesicular monoamine transporter type 2 PET imaging([^(18)F]AV-133)

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Neuroscience Bulletin 2014年第3期30卷 409-416页

作者： Yajing Liu Feng Yue Rongping Tang Guoxian Tao Xiaomei Pan Lin Zhu Hank F.Kung Piu Chan Department of Neurobiology Xuanwu Hospital of Capital Medical University Key Laboratory of Neurodegenerative Diseases Ministry of Education Xuanwu Hospital of Capital Medical University Beijing Key Laboratory on Parkinson's Disease Wincon Theracells biotechnologies inc. Key Laboratory of Radiopharmaceuticals Beijing Normal University Department of Radiology University of Pennsylvania

The 1-methyl-4-phenyl-1,2,3,4-tetrahydropyridine （MPTP）-induced parkinsonism model, particularly in non-human primates, remains the gold-standard for studying the pathogenesis and assessing novel therapies for Parkinson＇s disease. However, whether the loss of dopaminergic neurons in this model is progressive remains controversial, mostly due to the lack of objective in vivo assessment of changes in the integrity of these neurons. In the present study, parkinsonism was induced in cynomolgus monkeys by intravenous administration of MPTP （0.2 mg/kg） for 15 days; stable parkinsonism developed over 90 days, when the symptoms were stable. Noninvasive positron emission tomographic neuroimaging of vesicular monoamine transporter 2 with 9-[18F] fluoropropyl-（＋）-dihydrotetrabenazine （[18F]AV-133） was used before, and 15 and 90 days after the beginning of acute MPTP treatment. The imaging showed evident progressive loss of striatal uptake of [18SF]AV-133. The dopaminergic denervation severity had a significant linear correlation with the clinical rating scores and the bradykinesia subscores. These findings demonstrated that [18F]AV-133 PET imaging is a useful tool to noninvasively evaluate the evolution of monoaminergic terminal loss in a monkey model of MPTP-induced parkinsonism.

关键词： Parkinson's disease non-human primate [18F]AV-133 VMAT2 positron emission tomography

<i>In Vitro</i>Characterization of Cell Surface Properties of 14 Vaginal <i>Lactobacillus</i>Strains as Potential Probiotics

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Advances in Microbiology 2021年第2期11卷 144-155页

作者： Shao-Ji Li Jae-Seong So SignalDT biotechnologies (SZ) Inc. Shenzhen China Department of Biological Engineering Inha University Incheon Korea

Probiotics are live microorganisms which when administered in adequate amounts confer a health benefit on the host. Human-origin Lactobacillus is a preferable source of probiotic bacteria. This study screened 14 vaginal Lactobacillus strains as probiotic candidates by investigating probiotic-related cell surface characteristics including cell surface hydrophobicity (CSH), Lewis acidity/basicity, autoaggregation, and biofilm formation. Moderate to high CSH and autoaggregation, high basicity and low acidity were prevalent in the 14 tested strains. Biofilm formation varied in a large range among the 14 tested strains. CSH showed a high correlation with Lewis acidity and autoaggregation, while Lewis acidity was highly correlated with autoaggregation and biofilm formation. Four strains were selected as promising probiotic strains. This study was the first one to compare antibiotic sensitivity between biofilm-forming cells and planktonic cells of Lactobacillus species, and found that biofilm-forming cells of a L. fermentum strain had a significantly higher survival rate than planktonic cells in cefotaxime, cefmetazole and tetracycline, but were as sensitive to oxacillin and ampicillin as planktonic cells were.

关键词： Lactobacillus Probiotics Cell Surface Hydrophobicity Lewis Acidity Lewis Basicity Autoaggregation Biofilm Antibiotics

Improving Oxygen Binding of Desiccated Human Red Blood Cells

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Advances in Bioscience and Biotechnology 2016年第2期7卷 47-54页

作者： Steingrimur Stefansson David S. Chung Jamie Yoon Won Seok Yoo Young Wook Park George Kim David Hahn Huyen Le Sung-Jae Chung Stephen P. Bruttig David H. Ho hememics biotechnologies inc. Rockville MD USA Division of Biology & Medicine Brown University Providence RI USA Earl Warren College UC San Diego CA USA Department of Chemistry Michigan University Ann Arbor MI USA Seoul International School Seongnam South Korea Fuzbien Technology Institute Rockville MD USA Nauah Solutions Mclean VA USA Marymount University School of Arts & Science Arlington VA USA

Desiccating human red blood cells (RBCs) to increase their storage life has been the subject of intense research for a number of years. However, drying RBCs invariably compromises their integrity and has detrimental effects on hemoglobin function due to autoxidation. We have previously demonstrated an RBC desiccation and rehydration process that preserves RBC antigenic epitopes better than frozen RBCs. This study expands on those observations by examining what effects this desiccation process has on RBC hemoglobin function with respect to oxygen binding properties. In this paper, we examined RBCs from normal donors which were desiccated to 25% moisture content and stored dry for 2 weeks at room temperature prior to rehydration with plasma followed by structural and functional studies. Our data showed that approximately 98% of the RBCs were intact upon rehydration based on hemolysis assays. Oxygen dissociation curves for the desiccated/rehydrated RBCs showed a left shift compared to fresh RBCs (pO2 = 17 mmHg vs. 26 mmHg, respectively). The desiccated/rehydrated RBCs also showed an increase in methemoglobin compared to fresh RBCs (4.5% vs 0.9%, respectively). 2,3-Diphosphoglycerate concentration of the desiccated/rehydrated RBCs was reduced by 20%. In conclusion, although this RBC dehydration process preserves RBC integrity and hemoglobin oxygen binding properties better than most other dehydration techniques described so far, further optimization and long-term studies are needed to make this procedure acceptable for human transfusion.

关键词： Desiccation Red Blood Cells Oxygen Binding Hemolysis Methemoglobin 2 3-Diphosphoglycerate

Detection of the Pandemic H1N1/2009 Influenza A Virus by a Highly Sensitive Quantitative Real-time Reverse-transcription Polymerase Chain Reaction Assay

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Virologica Sinica 2013年第1期28卷 24-35页

作者： Zhu Yang Guoliang Mao Yujun Yuan-Chuan Chen Chengjing Liu Jun Luo Xihan Li Ke Zen Yanjun Pang Jianguo Wu Fenyong Liu Institute of Virology School of Life Sciences Nanjing University Taizhou Institute of Virology Jiangsu Affynigen biotechnologies Inc. State Key Laboratory of Virology College of Life Sciences Wuhan University College of Letters and Sciences University of Chicago Division of Infectious Diseases and Vaccinology School of Public Health University of California

A quantitative real time reverse-transcription polymerase chain reaction (qRT-PCR) assay with specific primers recommended by the World Health Organization (WHO) has been widely used successfully for detection and monitoring of the pandemic H1N1/2009 influenza A virus. In this study, we report the design and characterization of a novel set of primers to be used in a qRT-PCR assay for detecting the pandemic H1N1/2009 virus. The newly designed primers target three regions that are highly conserved among the hemagglutinin (HA) genes of the pandemic H1N1/2009 viruses and are different from those targeted by the WHO-recommended primers. The qRT-PCR assays with the newly designed primers are highly specific, and as specific as the WHO-recommended primers for detecting pandemic H1N1/2009 viruses and other influenza viruses including influenza B viruses and influenza A viruses of human, swine, and raccoon dog origin. Furthermore, the qRT-PCR assays with the newly designed primers appeared to be at least 10-fold more sensitive than those with the WHO-recommended primers as the detection limits of the assays with our primers and the WHO-recommended primers were 2.5 and 25 copies of target RNA per reaction, respectively. When tested with 83 clinical samples, 32 were detected to be positive using the qRT-PCR assays with our designed primers, while only 25 were positive by the assays with the WHO-recommended primers. These results suggest that the qRT-PCR system with the newly designed primers represent a highly sensitive assay for diagnosis of the pandemic H1N1/2009 virus infection.

关键词： RT-PCR检测逆转录聚合酶链反应 A型流感病毒实时定量敏感世界卫生组织流行性定量RT-PCR