Continuous cell lines have the characteristics of convenient culture, wide variety, fast growth rate, low cost, and rapid research, which makes them have always been the first choice for cell-level studies .Although continuous cell lines are full of treasures, there are still some limitations in their application.
In order to better understand the essence of life and reveal the laws of life activities of cells, scientists have carried out a series of researches on cell proliferation, movement, metabolism, death and other activities.
This artical intruduce three reasons to disuse continuous cell lines.Let's click here to learn more.
In conclusion, both cell strains and primary cells have played vital roles in advancing our understanding of cellular processes, disease mechanisms, and drug discovery. While cell strains provide a continuous and convenient supply of cells, primary cells offer a more authentic representation of human biology, enabling researchers to study specific tissues and diseases in a physiologically relevant context. The growth of cell strains and the significance of primary cells have propelled biomedical research forward, leading to breakthroughs in various fields and fostering the development of innovative therapeutic strategies. As technologies continue to evolve, primary cells will remain indispensable in further unraveling the complexities of human health and disease.
For decades, cell lines have played a critical role in scientific developments. In most cases, researchers just got data generated from cell lines. However, due to some weaknesses of cell lines, scientists become increasingly cautious about these generated results. But now the game has changed! Primary cells now are believed to be a more biologically relevant tool than cell lines for studying human and animal biology. And we design this primary cell culture guide aimed at showing new investigators the basic principles of primary cell and some practical culture skills.
1
CHAPTER 1 Microbiology: Then and Now
CHAPTER 2 The Chemical Building Blocks of Life
CHAPTER 3 Concepts and Tools for Studying Microorganisms
CHAPTER 4 Cell Structure and Function in the Bacteria and Archaea
CHAPTER 5 Microbial Growth and Nutrition
CHAPTER 6 Metabolism of Microorganisms
CHAPTER 7 Control of Microorganisms: Physical and Chemical Methods
1 Foundations of Microbiology
P A R T
n 1676, a century before the Declaration of Independence, a Dutch
merchant named Antony van Leeuwenhoek sent a noteworthy let-
ter to the Royal Society of London. Writing in the vernacular of his
home in the United Netherlands, Leeuwenhoek described how he used a simple
microscope to observe vast populations of minute, living creatures. His reports
opened a chapter of science that would evolve into the study of microscopic
organisms and the discipline of microbiology. At that time, few people, including
Leeuwenhoek, attached any practical significance to the microorganisms, but
during the next three centuries, scientists would discover how profoundly these
organisms influence the quality of our lives and the environment around us.
We begin our study of the microorganisms by exploring the grassroot devel-
opments that led to the establishment of microbiology as a science. These devel-
opments are surveyed in Chapter 1, where we focus on some of the individuals
who stood at the forefront of discovery. Today we are in the midst of a third Golden Age of microbiology and our
understanding of microorganisms continues to grow even as you read this book. Chapter 1, therefore, is an important
introduction to microbiology then and now.
Part 1 also contains a chapter on basic chemistry, inasmuch as microbial growth, metabolism, and diversity
are grounded in the molecules and macromolecules these organisms contain and in the biological processes they
undergo. The third chapter in Part 1 sets down some basic concepts and describes one of the major tools for study-
ing microorganisms. Much as the alphabet applies to word development, in succeeding chapters we will formulate
words into sentences and sentences into ideas as we survey the different groups of microorganisms and concentrate
on their importance to public health and human welfare.
Although most microorganisms are harmless—or even beneficial, some cause infectious disease. We will concentrate
on the bacterial organisms in Chapter 4, where we survey their structural frameworks. In Chapter 5, we build on these
frameworks by examining microbial growth patterns and nutritional requirements. Chapter 6 describes the metabolism
of microbial cells, including those chemical reactions that produce energy and use energy. Part 1 concludes by consider-
ing the physical and chemical methods used to control microbial growth and metabolism (Chapter 7).
I
Cells of Vibrio cholerae, transmitted to
humans in contaminated water and food, are
the cause of cholera.
62582_CH01_001_034.pdf 162582.
Contains everything about cell culture and cell culture laboratory. The data has been collected from various sources and piled up to make this presentation.
Method for physiologic phenotype characterization at the single-cell level in...Shashaanka Ashili
Intercellular heterogeneity is a key factor in a variety of core cellular processes including proliferation, stimulus response, carcinogenesis, and drug resistance. However, cell-to-cell variability studies at the single-cell level have been hampered by the lack of enabling experimental techniques. We present a measurement platform that features the capability to quantify oxygen consumption rates of individual, non-interacting and interacting cells
under normoxic and hypoxic conditions. It is based on real-time concentration measurements of metabolites of
interest by means of extracellular optical sensors in cell-isolating microwells of subnanoliter volume. We present the results of a series of measurements of oxygen consumption rates (OCRs) of individual non-interacting and interacting human epithelial cells. We measured the effects of cell-to-cell interactions by using the system’s capability to isolate two and three cells in a single well. The major advantages of the approach are: 1. ratiometric, intensity-based characterization of the metabolic phenotype at the single-cell level, 2. minimal invasiveness due to the distant positioning of sensors, and 3. ability to study the effects of cell-cell interactions on cellular respiration rates.
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
In conclusion, both cell strains and primary cells have played vital roles in advancing our understanding of cellular processes, disease mechanisms, and drug discovery. While cell strains provide a continuous and convenient supply of cells, primary cells offer a more authentic representation of human biology, enabling researchers to study specific tissues and diseases in a physiologically relevant context. The growth of cell strains and the significance of primary cells have propelled biomedical research forward, leading to breakthroughs in various fields and fostering the development of innovative therapeutic strategies. As technologies continue to evolve, primary cells will remain indispensable in further unraveling the complexities of human health and disease.
For decades, cell lines have played a critical role in scientific developments. In most cases, researchers just got data generated from cell lines. However, due to some weaknesses of cell lines, scientists become increasingly cautious about these generated results. But now the game has changed! Primary cells now are believed to be a more biologically relevant tool than cell lines for studying human and animal biology. And we design this primary cell culture guide aimed at showing new investigators the basic principles of primary cell and some practical culture skills.
1
CHAPTER 1 Microbiology: Then and Now
CHAPTER 2 The Chemical Building Blocks of Life
CHAPTER 3 Concepts and Tools for Studying Microorganisms
CHAPTER 4 Cell Structure and Function in the Bacteria and Archaea
CHAPTER 5 Microbial Growth and Nutrition
CHAPTER 6 Metabolism of Microorganisms
CHAPTER 7 Control of Microorganisms: Physical and Chemical Methods
1 Foundations of Microbiology
P A R T
n 1676, a century before the Declaration of Independence, a Dutch
merchant named Antony van Leeuwenhoek sent a noteworthy let-
ter to the Royal Society of London. Writing in the vernacular of his
home in the United Netherlands, Leeuwenhoek described how he used a simple
microscope to observe vast populations of minute, living creatures. His reports
opened a chapter of science that would evolve into the study of microscopic
organisms and the discipline of microbiology. At that time, few people, including
Leeuwenhoek, attached any practical significance to the microorganisms, but
during the next three centuries, scientists would discover how profoundly these
organisms influence the quality of our lives and the environment around us.
We begin our study of the microorganisms by exploring the grassroot devel-
opments that led to the establishment of microbiology as a science. These devel-
opments are surveyed in Chapter 1, where we focus on some of the individuals
who stood at the forefront of discovery. Today we are in the midst of a third Golden Age of microbiology and our
understanding of microorganisms continues to grow even as you read this book. Chapter 1, therefore, is an important
introduction to microbiology then and now.
Part 1 also contains a chapter on basic chemistry, inasmuch as microbial growth, metabolism, and diversity
are grounded in the molecules and macromolecules these organisms contain and in the biological processes they
undergo. The third chapter in Part 1 sets down some basic concepts and describes one of the major tools for study-
ing microorganisms. Much as the alphabet applies to word development, in succeeding chapters we will formulate
words into sentences and sentences into ideas as we survey the different groups of microorganisms and concentrate
on their importance to public health and human welfare.
Although most microorganisms are harmless—or even beneficial, some cause infectious disease. We will concentrate
on the bacterial organisms in Chapter 4, where we survey their structural frameworks. In Chapter 5, we build on these
frameworks by examining microbial growth patterns and nutritional requirements. Chapter 6 describes the metabolism
of microbial cells, including those chemical reactions that produce energy and use energy. Part 1 concludes by consider-
ing the physical and chemical methods used to control microbial growth and metabolism (Chapter 7).
I
Cells of Vibrio cholerae, transmitted to
humans in contaminated water and food, are
the cause of cholera.
62582_CH01_001_034.pdf 162582.
Contains everything about cell culture and cell culture laboratory. The data has been collected from various sources and piled up to make this presentation.
Method for physiologic phenotype characterization at the single-cell level in...Shashaanka Ashili
Intercellular heterogeneity is a key factor in a variety of core cellular processes including proliferation, stimulus response, carcinogenesis, and drug resistance. However, cell-to-cell variability studies at the single-cell level have been hampered by the lack of enabling experimental techniques. We present a measurement platform that features the capability to quantify oxygen consumption rates of individual, non-interacting and interacting cells
under normoxic and hypoxic conditions. It is based on real-time concentration measurements of metabolites of
interest by means of extracellular optical sensors in cell-isolating microwells of subnanoliter volume. We present the results of a series of measurements of oxygen consumption rates (OCRs) of individual non-interacting and interacting human epithelial cells. We measured the effects of cell-to-cell interactions by using the system’s capability to isolate two and three cells in a single well. The major advantages of the approach are: 1. ratiometric, intensity-based characterization of the metabolic phenotype at the single-cell level, 2. minimal invasiveness due to the distant positioning of sensors, and 3. ability to study the effects of cell-cell interactions on cellular respiration rates.
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
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A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
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This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
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Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
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1. - 1 -
Three reasons to disuse continuous
cell lines
In 1665, Robert Hooke, a British scientist, discovered and named the cells. Subsequently,
German biologists Matthias Jakob Schleiden and Theodor Schwann proposed the cell theory,
giving everyone a clearer understanding of the cell, a relatively independent unit that makes up
our lives.
In order to better understand the essence of life and reveal the laws of life activities of cells,
scientists have carried out a series of researches on cell proliferation, movement, metabolism,
death and other activities. In fact, as early as the 19th century, some people proposed the
concept of separating living cells from tissues, but the culture of animal cells was not studied
until 1950. From simple observation of cell development, to isolation of primary cells from
tissue, to obtaining continuous cell lines that can be passaged continuously. The
transformation of cells from an illusory concept to an indispensable experimental material for in
vitro research experiments has run through the entire history of biological development. Cells
used for scientific research are mainly divided into two types: primary cells directly isolated
from tissues and purchased cell lines.
Usually, the cells from the first to tenth passages isolated from the tissue are collectively
referred to as primary cells, and most of the primary cells will gradually stagnate, senesce and
die after this, and a very small number of cells that can survive to the fiftieth generation. After
fifty generations, the genetic information of cells has changed, and they have become a
continuous cell line. It has the characteristics of immortality, and some cells have lost contact
inhibition, can grow in multiple layers, and can even cause tumors after allogeneic inoculation.
Continuous cell lines have always been the first choice for cell-level studies due to their
immortality and rapid division. In addition, it has the characteristics of convenient culture, wide
variety, fast growth rate, low cost, and rapid research, which makes various continuous cell
lines widely used. For example, Hela cells, as the first human cell line that can be passaged
2. - 2 -
indefinitely, help scientists to more efficiently focus on human cell diseases and the mechanism
of action of active drugs, and are widely used in oncology, immunology, virology and other
disciplines.
In recent years, studies have found that although continuous cell lines are full of treasures,
there are still some limitations in their application.
Limitation 1: The biology of the cell is altered
During the research process, a large number of samples are often required, so the rapid
propagation and expansion of continuous cell lines are required. And the continuous passaging
process is prone to mutations, unrestricted passage may lead to changes in the genotype and
phenotype of the cell line, thereby affecting the experimental results. At the same time, the
biological characteristics of immortalized cell lines and living cells are quite different, and they
cannot fully represent the real environment in animals. Primary cells are considered to be more
representative of the in vivo tissue situation and have been legally recognized in some
countries/regions (Human Tissue Act 2004, UK), especially in the early toxicity assessment
tests of drugs, compared to cell lines, using primary cells isolated directly from patient tissue is
more appropriate.
Limitation 2: cell line cross-contamination
When it comes to cell contamination, everyone’s first reaction is that pathogenic
microorganisms cause the failure of cell experiments. However, what is mentioned here is not
to say that the bacterial proliferation in the culture system affects the experiment, but the
cross-contamination between cell lines, that is, the cell lines used for the experiment may be
mixed with other types of cells. This problem may be caused when the cell line is established,
or it may be caused by some improper operations, such as co-culture of multiple cells at the
same time, reuse of consumables, or caused by related cell culture products. Every inadvertent
operation can lead to the failure of the entire experiment.
In 2011, the United States issued a national standard for cell STR identification. Although many
researchers are still unaware of the seriousness of the problem, relevant institutions have
begun to sound the alarm:
In both the December 2014 and February 2015 issues of the journal Science, articles were
published explaining the seriousness of cell cross-contamination and misidentification, and
highlighting the consequences of contamination. It not only wastes time and energy, but also
the research results cannot be reproduced, and its impact is very serious. Therefore,
authoritative institutions such as NIH and ATCC have repeatedly issued calls for researchers to
identify cells. In April 2015, Nature announced that all its journals would require authors to
identify the cell lines used in their papers. Then in June, it was reported that a scientist
withdrew the Nature paper due to cell line problems. In October 2017, an article published in
the journal PLoS ONE stated that there was cross-contamination of the HeLa cell lines used in
more than 30,000 papers, rendering the research results invalid[1]. Another study in 2019
showed that at least 24% of human cell lines were contaminated with HeLa[2].
3. - 3 -
Limitation 3: Cell Application
Many cells fail to proliferate in vitro, and each experiment requires isolation of primary cells
from fresh tissue. Such as neurons, skeletal muscle cells, cardiomyocytes, pericytes, and
terminally differentiated hepatocytes, etc.
In addition, the state of primary cells is closest to the physiological environment in the body
and can maintain certain tissue biological characteristics. Therefore, it is the best choice for
evaluating drug efficacy and virulence, and at the same time, the probability of
cross-contamination is greatly reduced. In addition, for studies related to oncology and
immunology, if living animal models are involved, the isolation of primary cells is also required.
However, the difficulty of culturing primary cells is much higher than that of ordinary cell lines.
Meanwhile, the isolation and preparation of primary cells has always been an urgent problem
to be solved. Under the premise of ensuring reproducibility, how to efficiently prepare a
single-cell suspension with high activity?
RWD single cell suspension dissociator:
(https://www.rwdstco.com/product-item/single-cell-suspension-dissociator/) easily solves this
problem. The self-developed tissue processing tube, enzymatic digestion kit and built-in
optimization programs for preparing high-activity single-cell suspension and tissue
homogenate.
The instrument can quickly complete the preparation of single-cell suspension with high activity
and good uniformity, increasing the repeatability of experiments. It has four independent
channels, and the heating jacket can improve the efficiency of tissue processing. It is widely
used in immunology, oncology, neurobiology and other research fields.
After obtaining the single cell suspension, the cells need to be counted and analyzed for
viability and placed in a culture system or corresponding buffer system. RWD automatic cell
counter C100 (https://www.rwdstco.com/product-item/automatedcellcounter/) can accurately
count primary cells. With multiple fluorescence channels, it can quickly quantitatively analyze
cells in suspension, and simultaneously display brightfield and fluorescence images, clearly
showing the counting results and cell morphology. It is very suitable for immunology, vaccine
4. - 4 -
development, cell therapy, tumor research, stem cell and metabolic research and other fields.
Cell culture is the last step in the primary cell separation process.RWD CO2
incubator (https://www.rwdstco.com/product-item/incubators/) can precisely control the
temperature and carbon dioxide concentration, and can maintain a high-humidity environment.
The HEPA high-efficiency filter can effectively remove particulate pollution in the air, and the
140°C dry heat sterilization can realize regular sterilization and maintenance of the incubator,
providing a stable and clean culture environment for primary cell samples.
【References】
1. Serge P. J. M. Horbach,Willem Halffman. The ghosts of HeLa:How cell line misidentification
contaminates the scientific literature. PLoSONE,Published:
October 12,2017,doi:10.1371/journal.pone.0186281
2. Lin J,Chen L,Jiang W, Zhang H, Shi Y, Cai W. Rapid detection of low-level HeLa cell
contamination in cell culture using nested PCR. J Cell Mol Med.2019;23(1):
227–236. doi:10.1111/jcmm.13923