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Morax-Axenfeld Diplobacilli
''Moraxella lacunata'' is a rod-shaped, Gram-negative, nonmotile bacterium, generally present as diploid pairs. It causes one of the commonest forms of catarrhal conjunctivitis. History ''Moraxella lacunata'' was first described independently by Victor Morax (1896) and Theodor Axenfeld (1897), hence the alternate name "Morax-Axenfeld diplobacilli" and the name of eye infection in humans is sometimes called Morax-Axenfeld conjunctivitis. Characters It has the ability to change its morphology in laboratory. '' M. lacunata'' became shorter and tended to lose its Gram-negative staining characteristic when left out for 5 days. It also tended to retain these new characteristics on subsequent blood-agar transfers. Clinical significance Infection occurs mainly in adults, but can occur at any age. It is characterized by: * Chronic, mild angular blepharoconjunctivitis frequently localized on the lid at the outer canthus * Typical erythema Erythema (from the Greek , meaning red) is re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-negative
Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall sandwiched between an inner cytoplasmic cell membrane and a bacterial outer membrane. Gram-negative bacteria are found in virtually all environments on Earth that support life. The gram-negative bacteria include the model organism ''Escherichia coli'', as well as many pathogenic bacteria, such as ''Pseudomonas aeruginosa'', ''Chlamydia trachomatis'', and ''Yersinia pestis''. They are a significant medical challenge as their outer membrane protects them from many antibiotics (including penicillin), detergents that would normally damage the inner cell membrane, and lysozyme, an antimicrobial enzyme produced by animals that forms part of the innate immune system. Additionally, the outer leaflet of this membrane comprises a complex lipo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diploid
Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair, which chromosomes naturally exist as. Somatic cells, tissues, and individual organisms can be described according to the number of sets of chromosomes present (the "ploidy level"): monoploid (1 set), diploid (2 sets), triploid (3 sets), tetraploid (4 sets), pentaploid (5 sets), hexaploid (6 sets), heptaploid or septaploid (7 sets), etc. The generic term polyploid is often used to describe cells with three or more chromosome sets. Virtually all sexually reproducing organisms are made up of somatic cells that are diploid or greater, but ploidy level may vary widely between different organisms, between different tissues within the same organism, and at different stages in an organism's life cycle. Half ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conjunctivitis
Conjunctivitis, also known as pink eye, is inflammation of the conjunctiva, outermost layer of the white part of the eye and the inner surface of the eyelid. It makes the eye appear pink or reddish. Pain, burning, scratchiness, or itchiness may occur. The affected eye may have increased tears or be "stuck shut" in the morning. Swelling of the sclera, white part of the eye may also occur. Itching is more common in cases due to allergies. Conjunctivitis can affect one or both eyes. The most common infectious causes are viral infection, viral followed by bacterial infection, bacterial. The viral infection may occur along with other symptoms of a common cold. Both viral and bacterial cases are easily spread between people. Allergies to pollen or animal hair are also a common cause. Diagnosis is often based on signs and symptoms. Occasionally, a sample of the discharge is sent for microbial culture, culture. Prevention is partly by handwashing. Treatment depends on the underlying c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Victor Morax
Victor Morax, Paris, 1920 Victor Morax (16 March 1866 – 14 May 1935) was an ophthalmologist born in Morges, Switzerland. He studied in Freiburg (Germany) and Paris, and from 1891 to 1903, he worked at the Pasteur Institute in Paris. From 1903 to 1928, he was associated with the Hôpital Lariboisière, rejoining the Pasteur Institute as a permanent member in 1929. In 1930, he became a member of the Académie de Médecine. While at the Pasteur Institute, Morax discovered the bacillus '' Moraxella lacunata'', the cause of chronic conjunctivitis. The disease is sometimes referred to as either "Morax' disease" or as "Axenfeld's conjunctivitis", named after German ophthalmologist Theodor Axenfeld (1867-1930), who made his discovery of the bacillus during the same time period as did Morax. In 1923, he became vice-president of the "International League Against Trachoma" with bacteriologist Charles Nicolle (1866-1936) serving as its president. In 1929, he published a treatise on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theodor Axenfeld
Karl Theodor Paul Polykarpus Axenfeld (24 June 1867 – 29 July 1930) was a German ophthalmologist born in Smyrna (İzmir) in the Ottoman Empire to a German minister, who was a Jewish convert to Christianity and served as missionary in Asia Minor. As a child his family moved back to Germany, settling in the town of Godesberg. He received his medical doctorate in 1890 from the University of Marburg. In 1896 he became an assistant to Wilhelm Uhthoff (1853–1927) at Breslau, and during the following year, was appointed director of the university eye clinic in Rostock. In 1901 he attained the chair of ophthalmology in Freiburg, where he remained until his death in 1930. In 1925 he was chosen as president of the German Ophthalmological Society (''Deutsche ophthalmologische Gesellschaft''). Publications and research Axenfeld was involved in all aspects of ophthalmology and is associated with almost 200 written works involving the eye, including an important textbook of ophthalmology ti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphology (biology)
Morphology is a branch of biology dealing with the study of the form and structure of organisms and their specific structural features. This includes aspects of the outward appearance (shape, structure, colour, pattern, size), i.e. external morphology (or eidonomy), as well as the form and structure of the internal parts like bones and organs, i.e. internal morphology (or anatomy). This is in contrast to physiology, which deals primarily with function. Morphology is a branch of life science dealing with the study of gross structure of an organism or taxon and its component parts. History The etymology of the word "morphology" is from the Ancient Greek (), meaning "form", and (), meaning "word, study, research". While the concept of form in biology, opposed to function, dates back to Aristotle (see Aristotle's biology), the field of morphology was developed by Johann Wolfgang von Goethe (1790) and independently by the German anatomist and physiologist Karl Friedrich Burdach ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram Stain
In microbiology and bacteriology, Gram stain (Gram staining or Gram's method), is a method of staining used to classify bacterial species into two large groups: gram-positive bacteria and gram-negative bacteria. The name comes from the Danish bacteriologist Hans Christian Gram, who developed the technique in 1884. Gram staining differentiates bacteria by the chemical and physical properties of their cell walls. Gram-positive cells have a thick layer of peptidoglycan in the cell wall that retains the primary stain, crystal violet. Gram-negative cells have a thinner peptidoglycan layer that allows the crystal violet to wash out on addition of ethanol. They are stained pink or red by the counterstain, commonly safranin or fuchsine. Lugol's iodine solution is always added after addition of crystal violet to strengthen the bonds of the stain with the cell membrane. Gram staining is almost always the first step in the preliminary identification of a bacterial organism. While Gram s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canthus
The canthus (pl. canthi, palpebral commissures) is either corner of the eye where the upper and lower eyelids meet. More specifically, the inner and outer canthi are, respectively, the medial and lateral ends/angles of the palpebral fissure. The bicanthal plane is the transversal plane linking both canthi and defines the upper boundary of the midface. Etymology The word ' is the Latinized form of the Ancient Greek ('), meaning 'corner of the eye'. Population distribution The eyes of those of East Asian and some Southeast Asian people tend to have the inner canthus veiled by the epicanthus. In the Caucasian or double eyelid, the inner corner tends to be exposed completely. Commissures * The ''lateral palpebral commissure'' (commissura palpebrarum lateralis; external canthus) is more acute than the medial, and the eyelids here lie in close contact with the bulb of the eye. * The ''medial palpebral commissure'' (commissura palpebrarum medialis; internal canthus) is prolonged ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erythema
Erythema (from the Greek , meaning red) is redness of the skin or mucous membranes, caused by hyperemia (increased blood flow) in superficial capillaries. It occurs with any skin injury, infection, or inflammation. Examples of erythema not associated with pathology include nervous blushes. Types * Erythema ab igne * Erythema chronicum migrans * Erythema induratum * Erythema infectiosum (or fifth disease) * Erythema marginatum * Erythema migrans * Erythema multiforme (EM) * Erythema nodosum * Erythema toxicum * Erythema elevatum diutinum * Erythema gyratum repens * Keratolytic winter erythema * Palmar erythema Causes It can be caused by infection, massage, electrical treatment, acne medication, allergies, exercise, solar radiation (sunburn), photosensitization, acute radiation syndrome, mercury toxicity, blister agents, niacin administration, or waxing and tweezing of the hairs—any of which can cause the capillaries to dilate, resulting in redness. Erythema is a common sid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skin Maceration
Maceration is defined as the softening and breaking down of skin resulting from prolonged exposure to moisture. It was first described by Jean-Martin Charcot in 1877. Maceration is caused by excessive amounts of fluid remaining in contact with the skin or the surface of a wound for extended periods. Maceration often occurs with the application of a bandage to a wound, regardless of its mildness or severity. This occurs because the skin under the bandage becomes wet due to perspiration, urine or other bodily fluids. The excess moisture is sometimes called hyperhydration. One may also notice maceration after wearing non-breathable plastic or latex rubber gloves, which trap moisture against the skin. Wrinkles are the first sign that the skin is over-hydrated. In addition, macerated skin becomes extremely soft and takes on a whitish appearance. However, this white skin should not be confused with the pale, whitish appearance of the new epithelial tissue in a healing wound. Althou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-negative Bacteria
Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall sandwiched between an inner cytoplasmic cell membrane and a bacterial outer membrane. Gram-negative bacteria are found in virtually all environments on Earth that support life. The gram-negative bacteria include the model organism ''Escherichia coli'', as well as many pathogenic bacteria, such as ''Pseudomonas aeruginosa'', '' Chlamydia trachomatis'', and ''Yersinia pestis''. They are a significant medical challenge as their outer membrane protects them from many antibiotics (including penicillin), detergents that would normally damage the inner cell membrane, and lysozyme, an antimicrobial enzyme produced by animals that forms part of the innate immune system. Additionally, the outer leaflet of this membrane comprises a complex lipopol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
