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60-419: Auramine O is a diarylmethane dye used as a fluorescent stain . In its pure form, Auramine O appears as yellow needle crystals. It is insoluble in water and soluble in ethanol and DMSO . Auramine O can be used to stain acid-fast bacteria (e.g. Mycobacterium , where it binds to the mycolic acid in its cell wall) in a way similar to Ziehl–Neelsen stain . It can also be used as a fluorescent version of

120-588: A certain class of immune cells known as B lymphocytes , while antigens are defined as anything that elicits the generation of antibodies ( anti body gen erators). Immunology rests on an understanding of the properties of these two biological entities and the cellular response to both. It is now getting clear that the immune responses contribute to the development of many common disorders not traditionally viewed as immunologic, including metabolic, cardiovascular, cancer, and neurodegenerative conditions like Alzheimer's disease. Besides, there are direct implications of

180-401: A child's immune system responds favorably to protein antigens while not as well to glycoproteins and polysaccharides . In fact, many of the infections acquired by neonates are caused by low virulence organisms like Staphylococcus and Pseudomonas . In neonates, opsonic activity and the ability to activate the complement cascade is very limited. For example, the mean level of C3 in

240-590: A commercial scale. Early industrialization was conducted by J. Pullar and Sons in Scotland. The first synthetic dye, mauve , was discovered serendipitously by William Henry Perkin in 1856. The discovery of mauveine started a surge in synthetic dyes and in organic chemistry in general. Other aniline dyes followed, such as fuchsine , safranine , and induline . Many thousands of synthetic dyes have since been prepared. The discovery of mauve also led to developments within immunology and chemotherapy . In 1863

300-465: A disease or disorder is known as immunotherapy . Immunotherapy is most commonly used to treat allergies, autoimmune disorders such as Crohn's disease , Hashimoto's thyroiditis and rheumatoid arthritis , and certain cancers . Immunotherapy is also often used for patients who are immunosuppressed (such as those with HIV ) and people with other immune deficiencies. This includes regulating factors such as IL-2, IL-10, GM-CSF B, IFN-α. Clinical immunology

360-439: A living body - administered by injection or other means (intravital staining) - as the latter is (for instance) subject to higher safety standards, and must typically be a chemical known to avoid causing adverse effects on any biochemistry (until cleared from the tissue), not just to the tissue being studied, or in the short term. The term "vital stain" is occasionally used interchangeably with both intravital and supravital stains,

420-406: A microscope). As the visibility is meant to allow study of the cells or tissues, it is usually important that the dye not have other effects on the structure or function of the tissue that might impair objective observation. A distinction is drawn between dyes that are meant to be used on cells that have been removed from the organism prior to study (supravital staining) and dyes that are used within

480-418: A newborn is approximately 65% of that found in the adult. Phagocytic activity is also greatly impaired in newborns. This is due to lower opsonic activity, as well as diminished up-regulation of integrin and selectin receptors, which limit the ability of neutrophils to interact with adhesion molecules in the endothelium . Their monocytes are slow and have a reduced ATP production, which also limits

540-492: A non-genetic direct basis for the transmission. Aphids , for example, rely on several different symbionts for defense from key parasites, and can vertically transmit their symbionts from parent to offspring. Therefore, a symbiont that successfully confers protection from a parasite is more likely to be passed to the host offspring, allowing coevolution with parasites attacking the host in a way similar to traditional immunity. The preserved immune tissues of extinct species, such as

600-520: A phrase coined by Mark Schaller , specifically refers to psychological pathogen avoidance drivers, such as disgust aroused by stimuli encountered around pathogen-infected individuals, such as the smell of vomit . More broadly, "behavioural" ecological immunity has been demonstrated in multiple species. For example, the Monarch butterfly often lays its eggs on certain toxic milkweed species when infected with parasites. These toxins reduce parasite growth in

660-399: A previous bout of the disease could nurse the sick without contracting the illness a second time. Many other ancient societies have references to this phenomenon, but it was not until the 19th and 20th centuries before the concept developed into scientific theory. The study of the molecular and cellular components that comprise the immune system, including their function and interaction, is

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720-401: Is testosterone . Estradiol usually begins to act around the age of 10 and testosterone some months later. There is evidence that these steroids not only act directly on the primary and secondary sexual characteristics but also have an effect on the development and regulation of the immune system, including an increased risk in developing pubescent and post-pubescent autoimmunity. There

780-559: Is added to the dye bath to help the uptake of the dye onto the fiber. Basic dyes are also used in the coloration of paper . Direct or substantive dyeing is normally carried out in a neutral or slightly alkaline dye bath, at or near boiling point , with the addition of either sodium chloride (NaCl) or sodium sulfate (Na 2 SO 4 ) or sodium carbonate (Na 2 CO 3 ). Direct dyes are used on cotton , paper, leather , wool, silk and nylon . They are also used as pH indicators and as biological stains . Laser dyes are used in

840-405: Is also some evidence that cell surface receptors on B cells and macrophages may detect sex hormones in the system. The female sex hormone 17-β-estradiol has been shown to regulate the level of immunological response, while some male androgens such as testosterone seem to suppress the stress response to infection. Other androgens, however, such as DHEA , increase immune response. As in females,

900-486: Is the food dye . Because food dyes are classed as food additives , they are manufactured to a higher standard than some industrial dyes. Food dyes can be direct, mordant and vat dyes, and their use is strictly controlled by legislation . Many are azo dyes, although anthraquinone and triphenylmethane compounds are used for colors such as green and blue . Some naturally occurring dyes are also used. A number of other classes have also been established, including: By

960-581: Is the study of diseases caused by disorders of the immune system (failure, aberrant action, and malignant growth of the cellular elements of the system). It also involves diseases of other systems, where immune reactions play a part in the pathology and clinical features. The diseases caused by disorders of the immune system fall into two broad categories: Other immune system disorders include various hypersensitivities (such as in asthma and other allergies ) that respond inappropriately to otherwise harmless compounds . The most well-known disease that affects

1020-463: Is used. The very fine particle size gives a large surface area that aids dissolution to allow uptake by the fiber. The dyeing rate can be significantly influenced by the choice of dispersing agent used during the grinding. Azoic dyeing is a technique in which an insoluble Azo dye is produced directly onto or within the fiber. This is achieved by treating a fiber with both diazoic and coupling components . With suitable adjustment of dyebath conditions

1080-428: Is usually no marked improvement in their response to polysaccharides until they are at least one year old. This can be the reason for distinct time frames found in vaccination schedules . During adolescence, the human body undergoes various physical, physiological and immunological changes triggered and mediated by hormones , of which the most significant in females is 17-β-estradiol (an estrogen ) and, in males,

1140-562: The Republic of Georgia in a prehistoric cave dated to 36,000 BP . Archaeological evidence shows that, particularly in India and Phoenicia , dyeing has been widely carried out for over 5,000 years. Early dyes were obtained from animal , vegetable or mineral sources, with no to very little processing. By far the greatest source of dyes has been from the plant kingdom , notably roots, berries, bark, leaves and wood, only few of which are used on

1200-528: The Schiff reagent . Auramine O can be used together with Rhodamine B as the Truant auramine-rhodamine stain for Mycobacterium tuberculosis . It can be also used as an antiseptic agent. Dye The majority of natural dyes are derived from non-animal sources such as roots, berries, bark, leaves, wood, fungi and lichens . However, due to large-scale demand and technological improvements, most dyes used in

1260-487: The physiological functioning of the immune system in states of both health and diseases; malfunctions of the immune system in immunological disorders (such as autoimmune diseases , hypersensitivities , immune deficiency , and transplant rejection ); and the physical, chemical, and physiological characteristics of the components of the immune system in vitro , in situ , and in vivo . Immunology has applications in numerous disciplines of medicine, particularly in

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1320-534: The " danger model " (or "danger theory"), and the "discontinuity" theory. The danger model, suggested by Polly Matzinger and colleagues, has been very influential, arousing many comments and discussions. The body's capability to react to antigens depends on a person's age, antigen type, maternal factors and the area where the antigen is presented. Neonates are said to be in a state of physiological immunodeficiency, because both their innate and adaptive immunological responses are greatly suppressed. Once born,

1380-436: The active immune agents were soluble components (molecules) found in the organism's "humors" rather than its cells. In the mid-1950s, Macfarlane Burnet , inspired by a suggestion made by Niels Jerne , formulated the clonal selection theory (CST) of immunity. On the basis of CST, Burnet developed a theory of how an immune response is triggered according to the self/nonself distinction: "self" constituents (constituents of

1440-555: The addition of salt to produce a lake pigment . Textile dyeing dates back to the Neolithic period. Throughout history, people have dyed their textiles using common, locally available materials. Scarce dyestuffs that produced brilliant and permanent colors such as the natural invertebrate dyes Tyrian purple and crimson kermes were highly prized luxury items in the ancient and medieval world. Plant-based dyes such as woad , indigo , saffron , and madder were important trade goods in

1500-447: The antigen are Lymphocytes. Once they recognize, they secrete antibodies. Antibodies are proteins that neutralize the disease-causing microorganisms. Antibodies do not directly kill pathogens, but instead, identify antigens as targets for destruction by other immune cells such as phagocytes or NK cells. The (antibody) response is defined as the interaction between antibodies and antigens . Antibodies are specific proteins released from

1560-413: The beginning of the 20th century saw a battle between "cellular" and "humoral" theories of immunity. According to the cellular theory of immunity, represented in particular by Elie Metchnikoff , it was cells – more precisely, phagocytes – that were responsible for immune responses. In contrast, the humoral theory of immunity, held by Robert Koch and Emil von Behring , among others, stated that

1620-558: The body) do not trigger destructive immune responses, while "nonself" entities (e.g., pathogens, an allograft) trigger a destructive immune response. The theory was later modified to reflect new discoveries regarding histocompatibility or the complex "two-signal" activation of T cells. The self/nonself theory of immunity and the self/nonself vocabulary have been criticized, but remain very influential. More recently, several theoretical frameworks have been suggested in immunology, including " autopoietic " views, "cognitive immune" views,

1680-440: The central science of immunology. The immune system has been divided into a more primitive innate immune system and, in vertebrates , an acquired or adaptive immune system . The latter is further divided into humoral (or antibody ) and cell-mediated components. The immune system has the capability of self and non-self-recognition. An antigen is a substance that ignites the immune response. The cells involved in recognizing

1740-466: The child will produce a dampened response. Passively acquired maternal antibodies can suppress the antibody response to active immunization. Similarly, the response of T-cells to vaccination differs in children compared to adults, and vaccines that induce Th1 responses in adults do not readily elicit these same responses in neonates. Between six and nine months after birth, a child's immune system begins to respond more strongly to glycoproteins , but there

1800-409: The different aspects of the specialty and treat allergic conditions, primary immunodeficiencies and systemic autoimmune and autoinflammatory conditions. As part of their training fellows may do additional rotations in rheumatology , pulmonology , otorhinolaryngology , dermatology and the immunologic lab. When health conditions worsen to emergency status, portions of immune system organs, including

1860-410: The dyeing of cellulose acetate , and are water-insoluble. The dyes are finely ground in the presence of a dispersing agent and sold as a paste, or spray-dried and sold as a powder. Their main use is to dye polyester , but they can also be used to dye nylon, cellulose triacetate , and acrylic fibers. In some cases, a dyeing temperature of 130 °C (266 °F) is required, and a pressurized dyebath

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1920-503: The economies of Asia and Europe. Across Asia and Africa, patterned fabrics were produced using resist dyeing techniques to control the absorption of color in piece-dyed cloth. Dyes from the New World such as cochineal and logwood were brought to Europe by the Spanish treasure fleets, and the dyestuffs of Europe were carried by colonists to America. Dyed flax fibers have been found in

1980-493: The fabric in a solution of an organic compound, typically a nitrophenol derivative, and sulfide or polysulfide . The organic compound reacts with the sulfide source to form dark colors that adhere to the fabric. Sulfur Black 1, the largest selling dye by volume, does not have a well defined chemical structure. Some dyes commonly used in Staining: One other class that describes the role of dyes, rather than their mode of use,

2040-454: The fiber is attributed, at least partly, to salt formation between anionic groups in the dyes and cationic groups in the fiber. Acid dyes are not substantive to cellulosic fibers. Most synthetic food colors fall in this category. Examples of acid dye are Alizarine Pure Blue B, Acid red 88 , etc. Basic dyes are water-soluble cationic dyes that are mainly applied to acrylic fibers , but find some use for wool and silk. Usually acetic acid

2100-448: The fiber substrate. The covalent bonds that attach reactive dye to natural fibers make them among the most permanent of dyes. "Cold" reactive dyes, such as Procion MX , Cibacron F , and Drimarene K , are very easy to use because the dye can be applied at room temperature. Reactive dyes are by far the best choice for dyeing cotton and other cellulose fibers at home or in the art studio. Disperse dyes were originally developed for

2160-482: The fields of organ transplantation, oncology, rheumatology, virology, bacteriology, parasitology, psychiatry, and dermatology. The term was coined by Russian biologist Ilya Ilyich Mechnikov , who advanced studies on immunology and received the Nobel Prize for his work in 1908 with Paul Ehrlich "in recognition of their work on immunity". He pinned small thorns into starfish larvae and noticed unusual cells surrounding

2220-401: The forerunner to Bayer AG was formed in what became Wuppertal , Germany . In 1891, Paul Ehrlich discovered that certain cells or organisms took up certain dyes selectively. He then reasoned that a sufficiently large dose could be injected to kill pathogenic microorganisms, if the dye did not affect other cells. Ehrlich went on to use a compound to target syphilis , the first time a chemical

2280-470: The humoral response as well as the phagocitic activity of macrophage. B cells develop early during gestation but are not fully active. Maternal factors also play a role in the body's immune response. At birth, most of the immunoglobulin present is maternal IgG. These antibodies are transferred from the placenta to the fetus using the FcRn (neonatal Fc receptor). Because IgM, IgD, IgE and IgA do not cross

2340-606: The immune system (Yemeserach 2010). The specificity of the bond between antibody and antigen has made the antibody an excellent tool for the detection of substances by a variety of diagnostic techniques. Antibodies specific for a desired antigen can be conjugated with an isotopic (radio) or fluorescent label or with a color-forming enzyme in order to detect it. However, the similarity between some antigens can lead to false positives and other errors in such tests by antibodies cross-reacting with antigens that are not exact matches. The use of immune system components or antigens to treat

2400-483: The immune system are cellular in nature, and not associated with specific organs, but rather embedded or circulating in various tissues located throughout the body. Classical immunology ties in with the fields of epidemiology and medicine . It studies the relationship between the body systems, pathogens , and immunity. The earliest written mention of immunity can be traced back to the plague of Athens in 430 BCE. Thucydides noted that people who had recovered from

2460-477: The immune system in the infectious diseases (tuberculosis, malaria, hepatitis, pneumonia, dysentery, and helminth infestations) as well. Hence, research in the field of immunology is of prime importance for the advancements in the fields of modern medicine, biomedical research, and biotechnology. Immunological research continues to become more specialized, pursuing non-classical models of immunity and functions of cells, organs and systems not previously associated with

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2520-557: The immune system itself is AIDS , an immunodeficiency characterized by the suppression of CD4+ ("helper") T cells , dendritic cells and macrophages by the human immunodeficiency virus (HIV). Clinical immunologists also study ways to prevent the immune system's attempts to destroy allografts ( transplant rejection ). Clinical immunology and allergy is usually a subspecialty of internal medicine or pediatrics . Fellows in Clinical Immunology are typically exposed to many of

2580-652: The male sex hormones seem to have more control of the immune system during puberty and post-puberty than during the rest of a male's adult life. Physical changes during puberty such as thymic involution also affect immunological response. Ecoimmunology, or ecological immunology, explores the relationship between the immune system of an organism and its social, biotic and abiotic environment. More recent ecoimmunological research has focused on host pathogen defences traditionally considered "non-immunological", such as pathogen avoidance , self-medication, symbiont -mediated defenses, and fecundity trade-offs. Behavioural immunity,

2640-559: The modern world are synthetically produced from substances such as petrochemicals. Some are extracted from insects and/or minerals . Synthetic dyes are produced from various chemicals. The great majority of dyes are obtained in this way because of their superior cost, optical properties (color), and resilience (fastness, mordancy). Both dyes and pigments are colored, because they absorb only some wavelengths of visible light . Dyes are usually soluble in some solvent, whereas pigments are insoluble. Some dyes can be rendered insoluble with

2700-718: The nature of their chromophore , dyes are divided into: Dyes produced by the textile, printing and paper industries are a source of pollution of rivers and waterways. An estimated 700,000 tons of dyestuffs are produced annually (1990 data). The disposal of that material has received much attention, using chemical and biological means. A "vital dye" or stain is a dye capable of penetrating living cells or tissues without causing immediate visible degenerative changes. Such dyes are useful in medical and pathological fields in order to selectively color certain structures (such as cells) in order to distinguish them from surrounding tissue and thus make them more visible for study (for instance, under

2760-440: The newborn's phagocytic activity. Although, the number of total lymphocytes is significantly higher than in adults, the cellular and humoral immunity is also impaired. Antigen-presenting cells in newborns have a reduced capability to activate T cells. Also, T cells of a newborn proliferate poorly and produce very small amounts of cytokines like IL-2, IL-4, IL-5, IL-12, and IFN-g which limits their capacity to activate

2820-518: The offspring of the infected Monarch. However, when uninfected Monarch butterflies are forced to feed only on these toxic plants, they suffer a fitness cost as reduced lifespan relative to other uninfected Monarch butterflies. This indicates that laying eggs on toxic plants is a costly behaviour in Monarchs which has probably evolved to reduce the severity of parasite infection. Symbiont-mediated defenses are also heritable across host generations, despite

2880-457: The percentage of total cells that stain negatively. Because the dye determines whether the staining is supravital or intravital, a combination of supravital and vital dyes can be used to more accurately classify cells into various groups (e.g., viable, dead, dying). Immunology Immunology is a branch of biology and medicine that covers the study of immune systems in all organisms . Immunology charts, measures, and contextualizes

2940-406: The placenta, they are almost undetectable at birth. Some IgA is provided by breast milk . These passively-acquired antibodies can protect the newborn for up to 18 months, but their response is usually short-lived and of low affinity . These antibodies can also produce a negative response. If a child is exposed to the antibody for a particular antigen before being exposed to the antigen itself then

3000-474: The production of some lasers, optical media ( CD-R ), and camera sensors ( color filter array ). Mordant dyes require a mordant , which improves the fastness of the dye against water, light and perspiration . The choice of mordant is very important as different mordants can change the final color significantly. Most natural dyes are mordant dyes and there is therefore a large literature base describing dyeing techniques. The most important mordant dyes are

3060-532: The synthetic mordant dyes, or chrome dyes, used for wool; these comprise some 30% of dyes used for wool, and are especially useful for black and navy shades. The mordant potassium dichromate is applied as an after-treatment. It is important to note that many mordants, particularly those in the heavy metal category, can be hazardous to health and extreme care must be taken in using them. Vat dyes are essentially insoluble in water and incapable of dyeing fibres directly. However, reduction in alkaline liquor produces

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3120-447: The thorns. This was the active response of the body trying to maintain its integrity. It was Mechnikov who first observed the phenomenon of phagocytosis , in which the body defends itself against a foreign body. Ehrlich accustomed mice to the poisonous ricin and abrin. After feeding them with small but increasing dosages of ricin he ascertained that they had become "ricin-proof". Ehrlich interpreted this as immunization and observed that it

3180-427: The thylacine ( Thylacine cynocephalus ), can also provide insights into their biology. The study of the interaction of the immune system with cancer cells can lead to diagnostic tests and therapies with which to find and fight cancer. The immunology concerned with physiological reaction characteristic of the immune state. Inflammation is an immune response that has been observed in many types of cancers. This area of

3240-414: The thymus, spleen, bone marrow, lymph nodes, and other lymphatic tissues, can be surgically excised for examination while patients are still alive. Immunology is strongly experimental in everyday practice but is also characterized by an ongoing theoretical attitude. Many theories have been suggested in immunology from the end of the nineteenth century up to the present time. The end of the 19th century and

3300-404: The two components react to produce the required insoluble azo dye. This technique of dyeing is unique, in that the final color is controlled by the choice of the diazoic and coupling components. This method of dyeing cotton is declining in importance due to the toxic nature of the chemicals used. Sulfur dyes are inexpensive dyes used to dye cotton with dark colors. Dyeing is effected by heating

3360-408: The underlying concept in either case being that the cells examined are still alive. In a stricter sense, the term "vital staining" means the polar opposite of "supravital staining." If living cells absorb the stain during supravital staining, they exclude it during "vital staining"; for example, they color negatively while only dead cells color positively, and thus viability can be determined by counting

3420-565: The visible region (some examples are nitro , azo , quinoid groups) and an auxochrome which serves to deepen the color. This theory has been superseded by modern electronic structure theory which states that the color in dyes is due to excitation of valence π-electrons by visible light. Dyes are classified according to their solubility and chemical properties. Acid dyes are water - soluble anionic dyes that are applied to fibers such as silk , wool , nylon and modified acrylic fibers using neutral to acid dye baths. Attachment to

3480-412: The water-soluble alkali metal salt of the dye. This form is often colorless, in which case it is referred to as a Leuco dye , and has an affinity for the textile fibre. Subsequent oxidation reforms the original insoluble dye. The color of denim is due to indigo , the original vat dye. Reactive dyes utilize a chromophore attached to a substituent that is capable of directly reacting with

3540-541: Was abruptly initiated after a few days and was still in existence after several months. Prior to the designation of immunity , from the etymological root immunis , which is Latin for 'exempt', early physicians characterized organs that would later be proven as essential components of the immune system. The important lymphoid organs of the immune system are the thymus , bone marrow , and chief lymphatic tissues such as spleen , tonsils , lymph vessels , lymph nodes , adenoids , and liver . However, many components of

3600-448: Was used in order to selectively kill bacteria in the body. He also used methylene blue to target the plasmodium responsible for malaria . The color of a dye is dependent upon the ability of the substance to absorb light within the visible region of the electromagnetic spectrum (380–750 nm). An earlier theory known as Witt theory stated that a colored dye had two components, a chromophore which imparts color by absorbing light in

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