Thomas Schmitt

Nervous System Development Overview The development of a single human fertilized egg into an individual is largely mysterious. In the process, the developmental central nervous system is the most complex. The central nervous system is formed by the ectoderm of the embryo. In the neuroblast stage, the notochord is the central axis of the embryo that runs through the embryo early and induces the undifferentiated ectodermal cells above it to transform into the primordium of the central nervous system. First, the dorsal ectoderm cells above the notochord are elongated and thickened to form a front wide and narrow nerve plate; the edge of the nerve plate is thickened and pleated to form a nerve pleat; the central plate of the nerve plate is concave to form a nerve groove. Then, the nerve pleat moves to the midline of the back and finally closes to form a neural tube. The anterior part of the neural tube develops into a brain, and the posterior part develops into a spinal cord. From this ... Continue reading →

Blood-brain Barrier Overview The blood-brain barrier is a barrier system in which the capillary endothelial cells in the brain are closely connected to each other while interacting with surrounding pericytes and astrocytes. It precisely controls the exchange of substances between blood and brain tissue, which is essential for maintaining the stability of the microenvironment in the brain. Studies show that the cells that make up the blood-brain barrier regulate the development and function of the blood-brain barrier by expressing tight and adherent connexins, transporters, and related signaling molecules. In addition, neurons and microglia are also involved in the regulation of the blood-brain barrier under physiological and pathological conditions. Recent studies have shown that the occurrence and development of various neurological diseases are accompanied by the destruction of the structure and function of the blood-brain barrier. Therefore, the study of the blood-brain barrier ... Continue reading →

What is Toll-like receptor? Toll-like receptors (TLRs) are a class of proteins that play a key role in innate immunity. They are single domain trans-membrane receptors belong to pattern recognition receptors (PRRs) which usually expressed in sentinel cells such as macrophages dendritic cells and many other non-immune cells such as fibroblasts and epithelial cells. They recognize structurally conserved molecules derived from microbes which are called pathogen-associated molecular patterns (PAMPs) or self-derived molecules derived from damaged cells, referred as damage associated molecules patterns (DAMPs). PAMPs include various bacterial cell wall components such as lipopolysaccharide (LPS), peptidoglycan (PGN) and lipopeptides, as well as flagellin, bacterial DNA and viral double-stranded RNA. DAMPs include intracellular proteins such as heat shock proteins as well as protein fragments from the extracellular matrix. PRRs activate downstream signaling pathways that lead to the ... Continue reading →

Overview Growth differentiation factors (GDFs) are a subfamily of proteins belonging to the transforming growth factor beta superfamily that have functions predominantly in development. They are produced as inactive preproproteins which are then cleaved and assembled into active secreted homodimers. GDF dimers are disulfide-linked with the exception of GDF-3 and GDF-9. GDF proteins are important during embryonic development, particularly in the skeletal, nervous, and muscular systems. Members of GDF family Table 1. GDF family related products GDF Ligands GDF1 GDF2 GDF3 GDF5 GDF6 GDF7 GDF9 GDF10 GDF11 GDF15     GDF1 Growth differentiation factor 1 (GDF1) is a protein that in humans is encoded by the GDF1 gene. GDF1 belongs to the transforming growth factor beta superfamily that has a role in left-right patterning and mesoderm induction during embryonic development. It is found in the brain, spinal cord and peripheral nerves of embryos. GDF2 Growth differentiation factor 2 ... Continue reading →

Whether for thyroid disease or thyroid surgery, blood tests for thyroid function is indispensable. However, there are too many test items, and many patients found the high or low arrow on the laboratory report (often prompted to anomalies), which can frighten a lot of patients. In fact, there are different meanings for the anomalies in these thyroid test results, and many of them do not need to worry. So what are the implications of these results, and how to explain the different diseases? The following chart is a common test report, which basically covers common used inspection items: Table1. Laboratory results of the thyroid function test       T3 and T4 (ie triiodothyronine—TT3 and triiodothyronine—TT4) They are the products of thyroid hormone synthesis, and T4 has one more iodine group than T3. Abnormal results of these two suggest abnormalities in thyroid function, but often are not directly related to clinical manifestations. Therefore, abnormal ... Continue reading →

Clinically, some people often have repeated allergies, eczema and respiratory infections or other parts of the infection, in this case, in addition to some routine tests such as tests for white blood cells, immunoglobulin series, lymphocyte subsets, etc., the five immune immunoglobulin tests are also necessary. Although many people do these tests in the doctor’s advice, they do not know its role or clinical significance. Here you can find an explanation. 1. What is immunoglobulin? Immunoglobulin (Ig) refers to a class of globulin with antibody activity or with chemical structure similar to antibody, and it is the main reaction substances of humoral immune response. With anti-bacterial, anti-viral effect and strengthening the phagocytosis of cells function, as well as killing or dissolving pathogenic microorganisms in the complement of the collaboration, it is an important component of disease resistance in the body. Immunoglobulin is produced by plasma cells, widely found in ... Continue reading →

Influenza A viruses, the culprits of respiratory illness in humans, are a complex and multifaceted group of viruses. Among the numerous subtypes of Influenza A, H1N1 and H3N2 with a notorious history of causing seasonal epidemics and pandemics, demand special attention. Figure 1. The Spread of Influenza A. Influenza A H1N1, also known as the swine flu, is a formidable subtype of Influenza A virus that made its first appearance in pigs in 1930. Its ominous presence resulted in a pandemic in 2009, and the World Health Organization (WHO) declared it a public health emergency of international concern. The pandemic’s spread was unprecedented, reaching numerous countries and causing a significant impact on morbidity and mortality. In the first year alone, the H1N1 pandemic claimed between 151,700 and 575,400 lives. The H1N1 virus, a type A virus in the Orthomyxoviridae family, harbors a segmented RNA genome that codes for 11 proteins. ... Continue reading →

Introduction Malaria is caused by infection with Plasmodium parasites. Plasmodium belongs to unicellular eukaryote, and the Plasmodium that infects human body mainly comprises 5 kinds: Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, Plasmodium ovale and Plasmodium knowlesi. Among them, Plasmodium falciparum and Plasmodium vivax are the most widespread in the global epidemic area, and Plasmodium falciparum is the most important species that causes the death of malaria patients. The life cycle of Plasmodium is complex and mainly includes three stages: infrared stage, red inner stage and mosquito stage. Among them, both the red inner stage and the infrared stage of Plasmodium carry out asexual development and reproduction in the human body, while the mosquito stage carries out sexual reproduction and spore proliferation and development in Anopheles mosquitoes. In order to control and eliminate malaria, corresponding candidate vaccines are mainly designed for the three ... Continue reading →

After the host is infected by the virus, the immune system can generate a corresponding immune response. Antibodies specific to viral surface proteins produced at this time can often prevent the virus from adhering to the surface of host cells, making it incapable of infecting cells. However, in some cases, antibodies play the opposite role during viral infection, they assist the virus to enter the target cells and increase the infection rate, this phenomenon is antibody-dependent enhancement (ADE). The role of ADE was first reported by Hawkes in the 1960s. Since then, the presence of ADE has been found in the infection of more than 40 kinds of viruses in multiple families and genera. It is often difficult to prevent and control such viral diseases with ADE effects. Mechanism of ADE Action in Viral Infection This intricate mechanism has been the focus of intense scrutiny, with scientists examining the involvement of various immune cells such as ... Continue reading →

Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by bilateral motor (eg, bradykinesia, resting tremor, postural instability, rigidity) and nonmotor (eg, memory loss, depression) disability. About 10 million people worldwide suffer from Parkinson’s disease. Current PD treatments are limited to motor symptom management, such as dopamine replacement therapy or enhancing the activity of remaining dopaminergic neurons. There are no known treatments that slow progression or prevent the onset of the disease. Furthermore, PD patients are growing at an unprecedented rate and are expected to increase to 17.5 million by 2040. Although aging remains a major risk factor for PD, more than 20 genes have been found to be associated with PD onset and progression, suggesting therapeutic potential for Parkinson’s disease. The current drugs for the treatment of Parkinson’s disease are mainly levodopa, which forms ... Continue reading →

Biopharmaceutical impurities can be divided into two categories: extraneous contaminants and product-related impurities. Extraneous contaminants include microbial contamination, pyrogens, cellular components, components in culture media, substances from various steps in the production process, and substances from purification steps, etc. Various impurities and quantities will affect the safety of the final drug, and the identification, quantification, qualitative and control and removal of impurities are very important in the development process. Common biopharmaceutical impurities include: Protein A, G and L residues; double-stranded RNA (dsRNA) residues; host DNA residues; BSA residues; CHO host protein (HCP) residues. Figure1. The Production of biological products. Protein A, G and L residues Affinity chromatography for Protein A, G and L is a common method for purifying therapeutic antibodies. They can separate the ... Continue reading →

In recent years, with the changes in human environment and diseases, the incidence of fungal infections has been increasing year by year. Candida albicans is one of the important pathogens causing fungal infections. In addition, it is also an important food-borne pathogen. Therefore, it is of great significance to carry out research on detection methods of Candida albicans in the fields of medical clinical testing and food safety testing. Biological characteristics of Candida Albicans Candida albicans exists widely in nature, and also exists in the oral cavity, upper respiratory tract, intestinal tract and vagina of normal people. It is generally small in number in normal organisms, does not cause disease, and is conditionally pathogenic. When the body’s resistance is reduced or the flora is out of balance, Candida albicans will multiply and change its growth form to invade human cells and cause diseases. Figure 1. Candida albicans visualized using scanning electron ... Continue reading →

Inflammation is an important defense response of the body that can control and clear various endogenous or exogenous damaging factors acting on the body, and also has a role in repairing damage. However, excessive or persistent inflammation can also cause damage to tissues and organs. Calprotectin, named for its antibacterial function, is a heterodimer composed of S100A8 protein (also known as myeloid-related protein 8, calgranulin A) and S100A9 protein (also known as myeloid-related protein 14, calgranulin B), which are abundant in important inflammatory cells such as monocytes and neutrophils, and play an important role in the inflammatory process. Therefore, calprotectin has potential for diagnosis and even treatment of inflammation-related diseases, and is worth further study. Functions of Calprotectin Intracellular Functions of Calprotectin Inside the cell, calprotectin interacts with cytoskeletal components such as keratin, actin, and profilin in a calcium-dependent manner, and ... Continue reading →

Influenza A viruses, the culprits of respiratory illness in humans, are a complex and multifaceted group of viruses. Among the numerous subtypes of Influenza A, H1N1 and H3N2 with a notorious history of causing seasonal epidemics and pandemics, demand special attention. Figure 1. The Spread of Influenza A. Influenza A H1N1, also known as the swine flu, is a formidable subtype of Influenza A virus that made its first appearance in pigs in 1930. Its ominous presence resulted in a pandemic in 2009, and the World Health Organization (WHO) declared it a public health emergency of international concern. The pandemic’s spread was unprecedented, reaching numerous countries and causing a significant impact on morbidity and mortality. In the first year alone, the H1N1 pandemic claimed between 151,700 and 575,400 lives. The H1N1 virus, a type A virus in the Orthomyxoviridae family, harbors a segmented RNA genome that codes for 11 proteins. ... Continue reading →