Hytrin

By C. Randall. Point Loma Nazarene College.

Macewen became inter- incision corresponding to the transverse line just ested in the disease and the pathology of its defor- spoken of buy discount hytrin 2mg line. The length of the incision is slightly mities; he found that the epiphysial cartilages of greater than the largest chisel to be used generic hytrin 1mg. He therefore devised an instrument, children in the open Highlands escaped the wedge-shaped at the cutting end, which a skilled malady. The procedure Macewen devised for point out the depth to which the instrument has their cure became the standard operation in penetrated and thus serve as a guide. The osteotome performed in England was by Stromeyer Little in has so completely captivated the orthopedic 1865 at the Royal Orthopedic Hospital when, surgeon as a bone-cutting instrument that the using a mallet and chisel, he corrected a knock- chisel is entirely neglected and its use forgotten. Richard von Volkmann of Halle, Yet for the controlled shaving and molding of the most powerful advocate of Listerian prin- bone, as in sculpture, the chisel is incomparably ciples in Germany, was the first to perform the better tool; the osteotome was never intended osteotomy under antiseptic precautions when, in by its originator for anything but straight 1874, he corrected flexion ankylosis of the knee fissuring. Macewen, after reading von Volkmann’s Macewen in 1880 published his experiences in description of the operation, repeated the proce- a small book, which became a classic, entitled On dure in 1875 for a similar condition. Two years Osteotomy: with an enquiry into the aetiology and later he operated for knock-knee, removing some pathology of knock-knee, bow-leg and other bone from the inner condyle. It was he performed linear osteotomy for the first time translated into several languages. At the Interna- for correction of genu valgum, using a mallet and tional Congress of Medicine held at Copenhagen chisel. The same year, in a paper in the Lancet in 1884, he delivered an address on “Osteotomy entitled “Antiseptic Osteotomy,” he described this for Genu Valgum. They also be the uppermost part of the external border of the helped to vindicate antiseptic principles in patellar articular surface which can easily be felt surgery for which Lister was pleading. John Hunter, after disc was only concerned with the growth of the much patience, had wonderfully succeeded in shaft. He also believed, contrary to Duhamel and transplanting a human tooth to a cock’s comb. Ollier, that the periosteum had no osteogenetic Some scanty success was gained by others in the power; it was purely a limiting membrane giving transference of bone from one lower animal to direction to bone growth but taking no active part another. He excised bone shafts with the epiphyses transplant bone in a human being successfully. It in dogs but left the periosteum intact and found was a great pioneer achievement for at once it that there was no periosteal reproduction of the opened up a new field in bone surgery. In another animal a flap of periosteum was was described in a communication to the Royal lifted from a radius, detached at its lower end, Society in 1881 entitled “Observations concern- brought around some muscle fibers and reat- ing transplantation of bone. Illustrated by a case tached to the intact periosteum, but the strip of inter-human osseous transplantation, whereby produced no bone. Again he removed part of a over two-thirds of the shaft of a humerus was radial shaft and inserted a glass tube between the restored. It here forms an effective barrier against he succeeded in restoring the transverse ramus of osseous union, the ossific formation being one half of the jaw by transplantation of bone in absolutely limited by the periosteum and fibrous a girl 15 years of age who had the horizontal union results. He pouring of osteoblasts from broken surfaces into was particularly gratified with the result, for the the gap between the bones and into the surround- girl had been restored to her natural good looks ing tissues to form binding osseous deposits. Growth and reproduction are an inherent property of the osseous elements themselves. The result of 30 years’ clinical and experimental investigation The Growth of Bone was in 1912 published in a book, The Growth of Bone: Observations in Osteogenesis. This was Macewen, by his extended researches in the phys- followed in 1921 by another work, The Growth iology of bone, greatly advanced our knowledge and Shedding of the Antlers of the Deer. He proved that bone was a living casting of the antlers in early spring followed by tissue capable of transplantation; he believed the the growth of a new pair provided him with the graft played a vital part during the process of opportunity of closely studying rapid massive incorporation. They provided a greater surface Royal Infirmary and saw the effect of the appli- than the massive graft, each forming a center of cation of antiseptic principles in the treatment of ossification that threw out osteoblasts from its compound fractures, the impressive lowered mor- whole periphery. Herein he displays a remarkable tality and the hastened healing of wounds.

Often the bacteria contain a cell cheap hytrin 1mg with mastercard, which produces and secretes large amounts of an anti- bright spot under light microscopic illumination cheap 5mg hytrin free shipping. Depending on the identity of the infecting bacterium and on the physical state of the human host (primarily with respect to the efficiency of the immune system), bacteremic infections may not produce any symptoms. However, some infections do produce symptoms, ranging from an elevated temperature, as the immune system copes with the infection, to a spread of the infection to the heart (endocarditis or peri- carditis) or the covering of nerve cells (meningitis). In more rare instances, a bacteremic infection can produce a condition Light microscope image of Bacillus bacteria. The latter occurs when the infection overwhelms the ability of the body’s defense mechanisms to cope. Like the Septicemic infections usually result from the spread of spores of other bacterial species, the endospore of Bacillus an established infection. Bacteremic (and septicemic) infec- thuringiensis allows the organism to survive inhospitable con- tions often arise from bacteria that are normal resident on the ditions in a dormant state. Endospores that contain the pro- surface of the skin or internal surfaces, such as the intestinal toxin crystal can be applied to fields via crop-dusting aircraft. In their normal environments the bacteria The protoxin crystal is a hardy structure, and does not are harmless and even can be beneficial. However, in the gut of insects, where the pH entry to other parts of the body, these so-called commensal is very basic, the protoxin can go into solution. The entry of these commen- happens an insect enzyme splits the molecule. One of the sal bacteria into the bloodstream is a normal occurrence for toxin fragments, the delta endotoxin, confers the lethal effect most people. If the The delta endotoxin binds to the epithelial cells lining immune system is not functioning efficiently then the invad- the gut wall of the insect. By creating holes in the cells, the ing bacteria may be able to multiply and establish an infection. Another consequence of are another illness (such as acquired immunodeficiency syn- the destruction is a modification of the pH to a more neutral drome and certain types of cancer), certain medical treatments level that is hospitable for the germination of the endospores. The resuscitation and growth of Bacillus thuringiensis within Examples of bacteria that are most commonly associ- the insect gut kills the larva. In the recent three or four The generalized location of bacteremia produces gener- decades, with the advent of techniques of molecular alized symptoms. These symptoms can include a fever, chills, rearrangement, the specificity of the bacterium for target pain in the abdomen, nausea with vomiting, and a general feel- insect pests has been refined. Not all these symptoms are present at the some one percent of the worldwide use of fungicides, herbi- same time. Septic shock produces more drastic See also Bacteriocidal, bacteriostatic symptoms, including elevated rates of breathing and heartbeat, loss of consciousness and failure of organs throughout the body. The onset of septic shock can be rapid, so prompt med- BBacteremicACTEREMIC ical attention is critical. The discovery of bacteria in the blood should be taken Bacteremic is a term that refers to the ability of a bacterium to as grounds to suspect bacteremia, because bacteria do not typ- multiply and cause an infection in the bloodstream. Antibiotic therapy is usually initiated sion of the bloodstream by the particular type of bacteria is immediately, even if other options, such as the transient entry also referred to as bacteremia. In addition, If the invading bacteria also release toxins into the antibiotic therapy is prudent because many bacteremic infec- bloodstream, the malady can also be called blood poisoning or tions arise because of an ongoing infection elsewhere in the septicemia. Along with the prompt start of treatment, the antibiotic associated with septicemia. Use of an ineffective antibi- 44 WORLD OF MICROBIOLOGY AND IMMUNOLOGY Bacteria and bacterial infection otic can provide the bacteria with enough time to undergo lacking fimbrae, showing that these structures can indeed pro- explosive increases in number, whereas the use of an antibiotic mote the capacity of bacteria to cause infection. At the As with many other infections, bacteremic infections point of entry, usually at small breaks or lesions in the skin or can be prevented by observance of proper hygienic procedures mucosal surfaces, growth is often established in the submu- including hand washing, cleaning of wounds, and cleaning cosa. Growth can also be established on intact mucosal sur- sites of injections to temporarily free the surface of living bac- faces, especially if the normal flora is altered or eliminated. The rate of bacteremic infections due to surgery is much Pathogen growth may also be established at sites distant from less now than in the past, due to the advent of sterile surgical the original point of entry. Access to distant, usually interior, procedures, but is still a serious concern. If a pathogen gains access to tissues by adhesion and See also Bacteria and bacterial infection; Infection and invasion, it must then multiply, a process called colonization. The initial inoculum is rarely sufficient to cause BACTERIA AND BACTERIAL INFECTION damage.

Antigens are liv- mother to her fetus discount hytrin 5mg overnight delivery, thus conferring a temporary defense to the ing foreign bodies such as viruses generic hytrin 2mg overnight delivery, bacteria, and fungi that unborn child. Or they can be dust, chemicals, After birth, IgG is passed along to the child through the pollen grains, or food proteins that cause allergic reactions. But some of Antigens that cause allergic reactions are called aller- the Ig will still be retained in the baby from the placental trans- gens. A large percentage of any population, in varying mission until it has time to develop its own antibodies. It is an antibody that pro- the body or a blood transfusion that is not of the same blood vides a first line of defense against invading pathogens and type as itself. It is There are some substances such as nylon, plastic, or found in large quantities in the bloodstream and protects other Teflon that rarely display antigenic properties. While they have basic similarities, nonantigenic substances are used for artificial blood vessels, each IgA is further differentiated to deal with the specific component parts in heart pacemakers, and needles for hypo- types of invaders that are present at different openings of the dermic syringes. Practically everyone reacts to certain chemicals, for combines five Y-shaped units), it remains in the bloodstream example, the resin from the poison ivy plant, the venoms from where it provides an early and diffuse protection against insect and reptile bites, solvents, formalin, and asbestos. Viral invading antigens, while the more specific and effective IgG and bacterial infections also generally trigger an antibody antibodies are being produced by the plasma cells. For most people penicillin The ratio of IgM and IgG cells can indicate the various is not antigenic, but for some there can be an immunological stages of a disease. In an early stage of a disease there are response that ranges from severe skin rashes to death. The presence of a greater number of IgG Another type of antigen is found in the tissue cells of antibodies would indicate a later stage of the disease. If, for example, a kidney is transplanted, the antibodies usually form clusters that are in the shape of a star. These are called human leukocyte T-cells to help them in location of antigens. Research contin- antigens (HLA), and there are four major types of HLA subdi- ues on establishing more precise functions of this antibody. In order to avoid organ rejection, tis- The antibody responsible for allergic reactions, IgE acts sue samples are taken to see how well the new organ tissues by attaching to cells in the skin called mast cells and basophil match for HLA compatibility with the recipient’s body. In the presence of will also be used to suppress and control the production of environmental antigens like pollens, foods, chemicals, and helper/suppressor T-cells and the amount of antibodies. The hista- Red blood cells with the ABO antigens pose a problem mines cause the nasal inflammation (swollen tissues, running when the need for blood transfusions arises. Before a transfu- nose, sneezing) and the other discomforts of hay fever or other sion, the blood is tested for type so that a compatible type is types of allergic responses, such as hives, asthma, and in rare used. Type A blood has one kind of antigen and type B cases, anaphylactic shock (a life-threatening condition another. A person with type AB blood has both the A and B brought on by an allergy to a drug or insect bite). A person with type A tion for the role of IgE in allergy is that it was an antibody that blood would require either type A or O for a successful trans- was useful to early man to prepare the immune system to fight fusion. Type B blood would 27 Antibody and antigen WORLD OF MICROBIOLOGY AND IMMUNOLOGY described her experience in a letter to a friend. Children who were injected with pus from a smallpox victim did not die from the disease but built up immunity to it. Rejected in England by most doctors who thought the practice was bar- barous, smallpox vaccination was adopted by a few English physicians of the period. By the end of the eighteenth century, Edward Jenner (1749–1823) improved the effectiveness of vaccination by injecting a subject with cowpox, then later injecting the same subject with smallpox. The experiment showed that immu- nity against a disease could be achieved by using a vaccine that did not contain the specific pathogen for the disease. In the nineteenth century, Louis Pasteur (1822–1895) proposed the germ theory of disease. He went on to develop a rabies vaccine that was made from the spinal cords of rabid rabbits. Through a series of injections starting from the weakest strain of the disease, Pasteur was able, after 13 injections, to prevent the death of a child who had been bitten by a rabid dog. There is now greater understanding of the principles of vaccines and the immunizations they bring because of our knowledge of the role played by antibodies and antigens within the immune system.