By K. Marius. Guilford College.
First generation: Tolbutamide prozac 10 mg overnight delivery, Chlorpropamide Second generation: Glibenclamide purchase prozac 10 mg with mastercard, Glipizide Mechanism: hypoglycemic action is due to Stimulation of insulin release from β cell purchase 10 mg prozac visa, Depression of glucagon secretion discount prozac 10mg otc, Increase number of insulin receptor, Reduce insulin output from liver (Decrease hepatic gluconeogenesis and glycogenolysis) Pharmacokinetics: They are rapidly absorbed from the gastrointestinal tract. They are also extensively plasma protein bound and are mainly metabolized in the liver. The important toxic effects include: hypoglycemia, allergic skin rash and bone marrow depression, cholestatic jaundice (esp. Alcohol produces “Disulfirum” like action (flushing of the face, severe headache, vomiting etc. Biguinides They potentiate the hypoglycemic action of insulin and sulphonyl ureas but they don’t produce clinical hypoglycemia in diabetics. Biguanides include drugs like metformin and phenformin Mechanism: They do not stimulate the release of insulin. They increase glucose uptake in skeletal muscle, and have effects on glucose absorption and hepatic glucose production. Metformin is largely excreted unchanged in the urine and has a longer duration of action. Side effects: Nausea, vomiting, anorexia, diarrhea, abdominal cramp, lactic acidosis (esp. It also causes ejection of milk through contraction of the myo-epithelial cells around the alveoli of the mammary gland. Pharmacokinetics: It is inactivated orally and absorbed rapidly after intramuscular administration. Use: Induction of labor in women with uterine inertia, Relief of breast engorgement during lactation (few minutes before breast feeding) as nasal spray, Postpartum hemorrhage. Side effect: Oxytocin may cause over stimulation and leads to rupture of the uterus in the presence of cephalo-pelvic disproportion. Prostaglandins They induce labor at anytime during pregnancy but most effective at the third trimester. In female reproductive system prostaglandin E & F are found in ovaries, endometrium and menstrual fluid which is responsible for initiating and maintaining normal birth process. They are contraindicated in the presence of cardiac, renal, pulmonary or hepatic disease Ergometrine It is one of the ergot alkaloids with the ability to cause contraction of the uterine smooth muscle. Use: after delivery of placenta if bleeding is severe (Prevent postpartum bleeding) Adverse effect: Nausa, vomiting but serious toxic effects are rare. Female Sex Hormones and Hormonal Contraception Oestrogens These drugs can be classified into three groups. Synthetic: Diethylstibosterol Natural Estradiol: Estradiol is most potent, major secretory product of ovary. It is oxidized into esterone by liver; estrone is hydrated to estriol and synthesized by ovarian follicle, adrenal cortex, fetoplacental unit, and testis. Cervix: it makes cervical mucus thin and alkaline Vagina: Stratification, cornification and glycogen deposit is affected by estrogen. It is less effective orally due to complete metabolism by liver so it’s given through intramuscular route. Metabolic actions: (a) Thermogenic action (b) Competes with aldosterone at renal tubule so inhibits sodium reabsorption. They can also be classified as fixed dose combination (monophasic), biphasic and triphasic pills. Fixed dose combination: the commonest procedure is to administer one pill containing both an estrogen and progestin daily at bed time for 21 days. In biphasic and triphasic pills: these are combined oral contraceptive pills containing varying proportion of an estrogen and a progesterone designed to stimulate the normal pattern of menustral cycle. Medroxyprogestrone acetate (Depoprovera ) iii) Subcutanous implant L – norgestril (Norplant®) Mechanism: It makes cervical mucus thick, though & hostile and also alter endometrial wall B. Post coital “morning after” pill Oestrogen like Diethyl stilbosterol used within 72 hrs Combined oral contraceptive pills can also be used. Side effects of oral contraceptive: Thromboembolic complication, Weight gain & fluid retention, Menstrual disorder, Breast tenderness & fullness, Skin changes, Nausea & vomiting, Depressed mood, Reduced lactation Beneficial effects of estrogen /progesterone oral contraceptive 1) Reduced risk of endometrial Carcinoma, ovarian cyst 2) regular Menses, No excessive blood loss 3) Less premenustrual tension and dysmennorrhea 4) Relief of endometriosis Contraindication: In patients withcardiovascular diseases (hypertension, coronary heart disease) Thromboemolic disease, breast Cancer, diabetes mellitus, liver disease, women > 35 years (esp. Effect reduced when taken with enzyme inducers like Rifampicin, Phenytoin, Phenobarbitone etc. Oral contraceptive antagonize the effect of Coumarin anticoagulant and some antihypertensives Ovulation inducing drug These are drugs used in the treatment of infertility due to ovulatory failure. Therapeutic activity in inflammatory disorder is proportional to the glucocorticoid activity. They are not widely used in therapeutics rather its antagonists are of value in cases of edema. Thyroid and Antithyroid Drugs They inhibit the function of the thyroid gland and used in hyperthyroidism. Radioactive iodine ( I) Thiourea Compounds Inhibit the formation of throid hormone through inhibiting the oxidation of iodide to iodine by peroxidase enzyme and blocking the coupling of iodothryosines to form iodothyronines. Toxicities include drug fever, skin rashes, increased size and vascularity of the thyroid gland, and agranulocytosis. Ionic Inhibitors Potassium percholate prevents the synthesis of thyroid hormones through inhibition of uptake and concentration of iodide by the gland. It has the risk of aplastic anemia, therefore no longer used in the treatment of hyperthyroidism. Iodides: Improve manifestations of hyperthyroidism by decreasing the size and vascularity of the gland so they are required for preoperative preparation of the patient for partial thyroidectomy. Iodides act through inhibition of the “protease” enzyme which releases T3 and T4 from thyroglobulin, and organification. It is trapped and concentrated as ordinary iodine, which emits beta rays that act on parenchymal cells of the gland. It is contraindicated in pregnancy and lactation as it affects thyroid gland in the fetus and the infant. Propranolol This is an important drug which controls the peripheral manifestations of hyperthyroidism (tachycardia, tremor). Manifestations include hyperpyrexia, gastrointestinal symptoms, dehydration, tachycardia, arrhythmia, restlessness, etc. Management: It consists of infusion of intravenous fluids, supportive management, and also administration of propylthiouracil, sodium iodide, hydrocortisone, and propranolol. Discuss the mechanism and beneficial effects of combined oral contraceptive pills. Describe the mechanims of action and the adverse effects of antituberculois drugs. Discuss the use, mechanism of action and problems associated with anthelminthic drugs. Antimicrrobials: are chemical agents (synthetic/natural) used to treat bacterial, fungal and viral infections.
Paraphymosis Defnition: Is the retraction of foreskin behind the corona of the glans penis reducing a tonic efect buy 10mg prozac with amex. Causes - Trauma - Latrogenic Signs and symptoms - Oedema of the fore skin and glans penis - Pain - Fore skin ulceration Management - Reduction under anesthesia - Operation (circumcision) 7 buy 10mg prozac amex. Phymosis Defnition: Is tightness of the fore skin of such a degree as to prevent retraction discount 10mg prozac. Causes - Congenital - Secondary to infection Signs and symptoms - Ballooning of the fore skin micturation - Failure of retraction - Small contracted orifce Management - Circumcision Surgery Clinical Treatment Guidelines 177 Chapiter 7: Genito-Urinary Disorders 7 generic 10 mg prozac. Hypospadias Defnition: A condition where the urethral orifce opens in abnormal position on the ventral surface of the penis or scrotum. Causes /risk factors - Use of maternal estrogen or progesterone during pregnancy - Hereditary Signs and symptoms - Difculty directing the urinary stream and stream spraying - Chordee - Males with this condition ofen have a downward curve (ventral curvature or chordee) of the penis during an erection - Abnormal spraying of urine - Having to sit down to urinate - Malformed foreskin that makes the penis look “hooded” Investigations - A physical examination can diagnose this condition - A buccal smear and karyotyping - Urethroscopy - cystoscopy - Excretory urography Complications - Difculty with toilet training - Problems with sexual intercourse in adulthood - Urethral strictures and fstulas may form throughout the boy’s life Management - Infants with hypospadias should not be circumcised - For a Minor degree of hypospadias (e. Te repair may require multiple surgeries 178 Surgery Clinical Treatment Guidelines Chapiter 7: Genito-Urinary Disorders 7 • Relief of the chordee • Urethral reconstruction • In some cases, more surgery is needed to correct fstulas or a return of the abnormal penis curve Recommendations - Surgery is usually done before the child starts school - Surgery can be done as young as 4 months old, better before the child is 18 months old 7. Carcinoma of the Penis Te majority of penis malignancies are squamous cell carcinomas. Impotence Defnition: Persistent inability to obtain and sustain an erection sufcient for sexual intercourse. Causes - Psychological - Neurological causes (spinal cord lesions, myelodisplasia, multiple sclerosis, tabes dorsalis,peripheral neuropathies) - Diabetes mellitus - Endocrine (hypogonadotrophic hypogonadism Klinefelter’s Syndrome or surgical orchidectomy) - Low testosterone levels (prolactin producing tumors) - Vascular (atherosclerosis) - Trauma (perineal, posterior urethra, pelvic fracture leading to arterial injury, uraemicchronic dialysis - Iatrogenic (radical prostatectomy, cystoprostatectomy, neurological surgical procedures,transurethral endoscopic procedures, pelvic irradiation procedures) - Medication (centrally acting agents, anticholinergic agents (antidepressant), anti-androgenic agents (digoxin), hyperprolactinemic agent (cimetidine), sympatholitic agent (methyl dopa) Diagnosis - Detailed history - Physical examination - Length, plaques and deformity of the corporal bodies of penis - Presence or absence of testis - Size and consistency of the penis 180 Surgery Clinical Treatment Guidelines Chapiter 7: Genito-Urinary Disorders 7 - Gynecomastia (endrogene defciency) - Neurological assessment - Sensory function of the penis and perineal skin - Bulbo cavernosus refexe to evaluate the sacral refexes Investigations - Nocturnal penile turnescence (change in penis size during sleep) - Dynamic infusion cavernosometry and cavernosonography (to assess venous/corporal leak) Management Psychological • Treated by trained psychotherapist or sex therapist Medical therapy • Sildenafl(viagra), tadalafl (cialis) • Apomorphine (uprima) • Intracorporal administration of vasoactive substances (papaverine hydrochloride alone or associated with vasodilator like phentolamine, or prostaglandin E1) • Androgen replacement therapy with testosterone • Vacuum suction devices Surgical therapy • Penile prostheses • Vascular surgical techniques like micro surgical anastomosis of inferior epigastric artery to the dorsal penile artery Surgery Clinical Treatment Guidelines 181 Chapiter 7: Genito-Urinary Disorders 7. Urethra Meatal Stenosis Defnition: Is a narrowing of the opening of the urethra, the tube through which urine leaves the body. Causes - Not known - Predisposing factors are age, normally functioning testes, race, geographical location, sexual behavior, diet, alcohol, tobacco (no evidence that they play a part). Bladder Calculi/stones Defnition: Bladder calculi/stones are hard buildups of minerals that form in the urinary bladder. Causes - Calculi from the kidney - Bladder outfow obstruction - Presence of foreign bodies ( e. Bladder Cancer Defnition: Bladder cancer is a cancer that starts in the bladder; 90% is transitional cell carcinoma, 5-7% is squamous cell carcinoma, and 1-2% is adenocarcinoma/urachal carcinoma. Staging helps guide future treatment and follow-up and gives idea on patient prognosis. Cystocele Defnition: Is a medical condition that occurs when the tough fbrous wall between a woman’s bladder and her vagina is torn by childbirth, allowing the bladder to herniate into the vagina. Urinary Incontinence Defnition: Is the involuntary loss of urine Classifcation Classifcation of incontinence according to anatomical abnormality Class Sub- class Causes/risk factors Signs and symptoms Urethral Urethral Involuntary abnormalities incompetence urine loss Incontinence less common in men Urethral afer prostatectomy incontinence or pelvic fracture Bladder Inhibited detrusor Frequency and abnormality contractions by: urgency (urge Neuropathic incontinence) (detrusor hyperrefexia) non neuropathic (detrusor instability Non urinary impaired mobility abnormalities(in Impaired mental elderly patients) function Non urethral Fistula incontinence Ureteral ectopia Classifcation of incontinence according to clinical presentation Stress Ref. Vesico-Ureteric Refux Defnition: A congenital condition from the ureteral bud coming of too close to the urogenital sinus on the mesonephric duct which result in short intravesical length (intramural) of ureter. Urine travels retrograde from the bladder into the ureter and ofen into the kidney. Calculus Calcium stones (Ca oxalate, Ca phosphate) are the most common types in 70% of the cases. Management Palliation • Renal artery embolisation (may stop hematuria) • Chemotherapy (10% response rate) • Hormonal therapy (5% response rate) • Immunotherapy (under review) Surgery • Partial nephrectomy, if small peripheral lesions • Radical nephrectomy (Gerota’s fascia and regional lymphnodes) • Isolated lung metastases should also be removed surgically 7. Pelvi-Ureteric Junctions Defnition: Blockage of the ureter where it meets the renal pelvis. Cause - Congenital from either abnormalities of the muscles itself or crossing vessels. Signs and symptoms - Abdominal mass in the new born - Flank pain and infection in later life Surgery Clinical Treatment Guidelines 195 Chapiter 7: Genito-Urinary Disorders Investigations - Ultrasound - Diuretic renal scan Management - Pyeloplasty (Anderson- Hayne) 7. Tey account for approximately 10% of all renal tumours and approximately 5% of all urotherial tumours. A urethral catheter should be lef in situ for at least 10 days - High fstula (supratrigonal): Suprapubic approach 7. Posterior Urethral Valves Defnition: Obstructive urethral lesions usually diagnosed in male newborns and infants. Cause and Risk factors - Congenital Signs and symptoms - Assymptomatic till adolescence or childhood in incomplete valves - Urinary retention - Weak stream - Dysuria (infection) - Able to pass catheter without difculty Investigations - Urinalysis - Ultrasound scan - Voiding cyctogram (dilatation of the urethra above the valves) Management - Detect and treat early to avoid renal failure - Suprapubic catheter - Transurethral resection Surgery Clinical Treatment Guidelines 199 Chapiter 7: Genito-Urinary Disorders 7. Urethral Stricture Defnition: Congenital narrowing of the urethra Cause - Duplication of the urethra. Causes - Idiopathic - Predisposing factors: age, normally functioning testes, sexual behavior, diet, alcohol, tobacco (no evidence that they play a part) 200 Surgery Clinical Treatment Guidelines Chapiter 7: Genito-Urinary Disorders 7 Signs and symptoms - Nocturia - Urinary urgency and frequency - Acute urinary retention - Urinary tract infections - Renal failure - Urinary stones - Haematuria Management Conservative management Medical therapy • Alpha Blockers: e. Adenocarcinoma Defnition: Adenocarcinoma is a cancer originating in glandular epithelial tissue. Epithelial tissue includes, but is not limited to, skin, glands and a variety of other tissue that lines the cavities and organs of the body. It is of two forms, transitional cell carcinoma (> 90%) and squamous cell carcinoma (5-7%). Causes/Risk factors - Cigarette smoking - Chemical exposure at work (carcinogens - dye workers, rubber workers, aluminum workers, leather workers, truck drivers, and pesticide applicators) - Chemotherapy (e. Renal Cell Carcinoma Defnition: Renal cell carcinoma is a type of kidney cancer that starts in the lining of the kidney tubules. Burns Defnition: Burns are skin and tissue damage caused by exposure to or contact with temperature extremes, electrical current, a chemical agent or radiation. Electrical Burns Defnition: Electrical burns are body injuries caused by electrical current itself. Te current generates intense heat along its path through the body, which can lead to severe muscle, nerve and blood vessel damage. Animal Bites Defnition: Animal bites are wounds inficted on the body due to animals sinking teeth into one’s body. Animal bites and scratches, even when they are minor can become infected and spread bacteria to other parts of the body. Whether the bite is from a family pet or an animal in the wild, scratches and bites can carry disease. Animal Type Evaluation and Post-exposure 9 Disposition of Prophylaxis Animal Recommendations Dogs and cats Healthy and available Should not begin prophylaxis, 10 days observation, unless animal develops symptoms of rabies Rabid or suspected Immediate rabid vaccination (consider also tetanus toxoids) Unknown (escaped) Consult public health ofcials Skunks, Regarded as rabid Immediate raccoons, bats, unless geographic area vaccination foxes, and is known to be free of most other rabies or until animal carnivores; proven negative by woodchucks laboratory tests Livestock, Consider individually Consult public health rodents, and ofcials; bites of lagomorphs squirrels, hamsters, (rabbits and guinea pigs, gerbils, hares) chipmunks, rats, mice, other rodents, rabbits, and hares almost never require anti-rabies treatment Surgery Clinical Treatment Guidelines 213 Chapiter 9: Bites and Stings of Animals and Insects 9. Rabies Defnition: Rabies is a deadly viral infection that is mainly spread by infected animals. Snakebites and Venom Defnition: Poisonous snakes inject venom using modifed salivary glands The venom apparatus Venomous snakes of medical importance have a pair of enlarged teeth, the fangs, at the front of their upper jaw. Tese fangs contain a venom channel (like a hypodermic needle) or groove along which venom can be introduced deep intp the tissue of their natural prey. If a human is bitten, venom is usually injected subcutaneously or intramuscularly. Spitting cobras can squeeze the venom out of the tips of their fangs, producing a fne spray directed toward the eyes of an aggressor.
Role of domestic ducks in the propagation and biological evolution of highly pathogenic H5N1 inßuenza viruses in Asia order prozac 10mg with mastercard. Receptor speciÞcity of inßuenza A viruses from sea mammals correlates with lung sialyloligosaccharides in these animals cheap prozac 10 mg without a prescription. Generation of a highly pathogenic avian inßuenza A virus from an avirulent Þeld isolate by passaging in chicken buy generic prozac 10 mg on line. Development of enzyme-linked immunosorbent assay with nucleoprotein as antigen for detection of antibodies to avian inßuenza virus order 10 mg prozac with mastercard. Comparative pathobiology of low and high pathogenicity H7N3 Chilean avian inßuenza viruses in chicken. Antibody response in individuals infected with avian inßuenza A (H5N1) viruses and detection of anti-H5 antibody among household and social contacts. Is virulence of H5N2 inßuenza viruses in chicken associated with loss of carbohydrate from the hemagglutinin? Cells in the respiratory and intestinal tracts of chicken have different proportions of both human and avian inßuenza virus receptors. Neurotropism of highly pathogenic avian inßuenza virus A/chicken/Indonesia/2003 (H5N1) in experimentally infected pigeons (Columbia livia f. Transmission of H7N7 avian inßuenza A virus to human beings during a large outbreak in commercial poultry farms in the Netherlands. H5N2 avian inßuenza outbreak in Texas in 2004: the Þrst highly pathogenic strain in the United States in 20 years? Characterization of H9 subtype inßuenza viruses from the ducks of southern China: a candidate for the next inßuenza pandemic in humans? Generation of seal inßuenza virus variants pathogenic for chicken, because of hemagglutinin cleavage site changes. Avian-to-human transmission of H9N2 subtype inßuenza A viruses: relationship between H9N2 and H5N1 human isolates. A mouse model for the evalua- tion of pathogenesis and immunity to inßuenza A (H5N1) viruses isolated from humans. Vaccination with infectious laryngotra- cheitis virus recombinants expressing the hemagglutinin (H5) gene. Avian inßuenza (H5N1) viruses isolated from humans in Asia in 2004 exhibit increased virulence in mammals. Analysis of the 1999-2000 highly pathogenic avian inßuenza (H7N1) epidemic in the main poultry-production area in northern Italy. The surface glycoproteins of H5 inßuenza viruses isolated from humans, chicken, and wild aquatic birds have distinguish- able properties. Neuraminidase is im- portant for the initiation of inßuenza virus infection in human airway epithelium. Comparison of hemagglutination-inhibition, agar gel precipitin, and enzyme-linked immunosorbent assay for measuring antibodies against inßuenza viruses in chicken. Comparative pathology of chicken experimentally inoculated with avian inßuenza viruses of low and high pathoge- nicity. Clinical, gross, and microscopic Þndings in different avian species naturally infected during the H7N1 low- and high-pathogenicity avian inßuenza epidemics in Italy during 1999 and 2000. Epidemiology, pathol- ogy, and immunohistochemistry of layer hens naturally affected with H5N1 highly patho- genic avian inßuenza in Japan. Molecular analysis of the hemagglu- tinin genes of Australian H7N7 inßuenza viruses: role of passerine birds in maintenance or transmission? Intersegmental recombination between the hemag- glutinin and matrix genes was responsible for the emergence of a highly pathogenic H7N3 avian inßuenza virus in British Columbia. Payungporn S, Phakdeewirot P, Chutinimitkul S, Theamboonlers A, Keawcharoen J, Oraveerakul K, Amonsin A, Poovorawan Y. Cocirculation of avian H9N2 and contemporary ‘human‘ H3N2 inßuenza A viruses in pigs in southeastern China: potential for genetic reassortment? Virulence-associated sequence duplication at the hemagglutinin cleavage site of avian inßuenza viruses. Pathogenicity of a Hong Kong-origin H5N1 highly pathogenic avian inßuenza virus for emus, geese, ducks, and pigeons. Susceptibility of laughing gulls (Larus atricilla) to H5N1 and H5N3 highly pathogenic avian inßuenza viruses. Comparative susceptibility of selected avian and mammalian species to a Hong Kong-origin H5N1 high-pathogenicity avian influenza virus. Serological analysis of serum samples from humans exposed to avian H7 inßuenza viruses in Italy between 1999 and 2003. Do hemagglutinin genes of highly pathogenic avian inßuenza viruses constitute unique phylogenetic lineages? Vergleichende sero-immunologische Untersuchungen über die Viren der Inßuenza und klassischen Geßügelpest. Development and validation of a competitive enzyme- linked immunosorbent assay for detection of type A inßuenza antibodies in avian sera. Ice as a reservoir for pathogenic human viruses: speciÞcally, caliciviruses, inßuenza viruses, and enteroviruses. Avian inßuenza A virus (H7N7) epidemic in The Netherlands in 2003: course of the epidemic and effectiveness of control measures. Failure of a recombinant fowl poxvirus vaccine contain- ing an avian inßuenza hemagglutinin gene to provide consistent protection against inßuenza in chicken preimmunized with a fowl pox vaccine. EfÞcacy of recombinant fowl poxvirus vaccine in pro- tecting chicken against a highly pathogenic Mexican-origin H5N2 avian inßuenza virus. Protection against diverse highly pathogenic H5 avian inßuenza viruses in chicken immunized with a recombinant fowlpox vaccine containing an H5 avian inßuenza hemagglutinin gene insert. Recombinant paramyxovirus type 1- avian inßuenza-H7 virus as a vaccine for protection of chicken against inßuenza and New- castle disease. Protective efÞcacy in chicken, geese and ducks of an H5N1-inactivated vaccine developed by reverse ge- netics. Acylation-mediated membrane anchoring of avian inßuenza virus hemagglutinin is essential for fusion pore formation and virus infec- tivity. Importance of conserved amino acids at the cleavage site of the haemagglutinin of a virulent avian inßuenza A virus. Avian inßuenza A(H5N1)- update 31: Situation (poultry) in Asia: need for a long-term response, comparison with previous outbreaks. Matrix gene of inßuenza a viruses isolated from wild aquatic birds: ecology and emergence of inßuenza a viruses. Deduced amino acid se- quences at the haemagglutinin cleavage site of avian inßuenza A viruses of H5 and H7 subtypes. Enhanced recovery of avian inßuenza virus isolates by a combination of chicken embryo inoculation methods. Genetic characterization of the pathogenic inßuenza A/Goose/Guangdong/1/96 (H5N1) virus: similarity of its hemagglutinin gene to those of H5N1 viruses from the 1997 outbreaks in Hong Kong. Clinical features and rapid viral diagnosis of human disease associated with avian inßuenza A H5N1 virus.
Using higher magnification prozac 10mg on line, examine the muscle layers and notice that the musculature is skeletal mixed with bundles of smooth muscle fibers due to the level of the esophagus at which this section was taken purchase prozac 10mg on line. In cross-section note that the skeletal muscle fibers resemble rounded polygons separated by the endomysium with the nuclei clearly visible the periphery buy prozac 10mg line. Why do smooth muscle fibers in cross section have different diameters and why do some of these fail to show nuclei? During this lab generic 10 mg prozac with visa, become familiar with the morphology of mature peripheral blood cells and study the stages of blood development. The cellular or formed elements of peripheral blood are classified according to the details of their appearance following staining with polychromic stains, e. After finding an area that is well smeared and well stained, use the highest magnification to examine the blood cells, particularly the leukocytes. This slide does not have basophils, which account for less than one percent of the total number of leukocytes. There are stem cells that are precursors of both the red and white blood cell series, however because their proportion in bone marrow is low it is unlikely that you will be able to recognize them in your slides. The student should bear in mind that the frequency of any given cell type or stage of differentiation in the marrow is a complex function related to the relative frequency of the cells in the blood, to the half life of the cell type in the circulation, and to the maturation time of the cells in the marrow. The most frequent precursor series is the erythroid cell series, followed closely by the neutrophilic series. Distinctions between the cells of the granulocytic series are based on nuclear morphology and the size and staining properties of the granules. Criteria for evaluating cell type and stage of maturation are as follows: Size of the cell and its nucleus: In general there is a gradual decrease in size of the cell and its nucleus with maturation. Appearance of the chromatin network in the nucleus: Immature cells have a delicate fine- meshed chromatin network. Presence or absence of nucleoli: Nucleoli are visible as pale blue circular areas within the chromatin network of immature cells. Cytoplasmic basophilia: Very immature cells have pale blue cytoplasm, due to the presence of only a few scattered ribosomes. Specialized cell products: Accumulation of hemoglobin in erythroid cells, and the appearance of granules and their type in granulocytes. Basophilic erythroblast - This cell is usually smaller and the nucleus, which is intensely heterochromatic, is centrally located. The cytoplasm is a deeper blue color than that of the proerythroblast, due to the mixture of abundant free ribosomes and the initiation of hemoglobin synthesis. Polychromatophilic erythroblast - The nucleus is intensely heterochromatic, and the cytoplasm is now a characteristic lilac color. The basophilia is due to the cytoplasmic ribosomes, and the acidophilia is due to the increase in the 38 amount of hemoglobin being synthesized by the ribosomes. Normoblast (orthochromatic erythroblast) - The nucleus has become pyknotic and therefore is very dark in appearance. Occasionally there is still some residual basophilia in the cytoplasm of these cells, due to the retention of some ribosomes. Such immature red cells are called reticulocytes because of the so-called reticulated pattern of cytoplasmic basophilia. Under normal conditions, a small percentage of reticulocytes enter the circulation before completing their maturation. However, when there is a great increase in erythrocyte production the percentage of reticulocytes entering the blood increases. The myeloblast is a large cell with a large ovoid pale-staining nucleus, 2 to 5 nucleoli, and lightly basophilic cytoplasm (due to a scattering of ribosomes). Promyelocyte: This large cell is very similar to a myeloblast, but can be distinguished by the presence of a few azurophilic granules (pink-purple, primary lysosomes) in its cytoplasm. Myelocyte: The promyelocyte in turn gives rise to eosinophilic, neutrophilic and basophilic myelocytes, which have both azurophilic and specific granules according to their respective cell line. These cells can be identified by the round nucleus and by the accumulation of specific granules in their cytoplasm. Metamyelocytes: This stage can be identified by the indented nucleus and the presence of their specific cytoplasmic granules. You may be able to identify the unstained image of the Golgi complex in the region where the nucleus is indented. Mature granulocytes: The mature cells can be recognized by their complex nuclear morphologies and their specific granules. Do not confuse the fine granules of the neutrophil (which may appear lightly acidophilic) for the coarser granules of eosinophils or basophils. The most immediately obvious cell type will be the enormous megakaryocyte which gives rise to blood platelets. Choose an area of this slide where the cells are not too closely smeared to study the cells of the erythroid and granulocyte series. You should be able to assign a well-fixed and well-stained cell to either the erythrocyte or granulocyte line of development. If a cell in the granulocyte line already has specific granules it should be further classified into the neutrophilic, eosinophilic, or basophilic series and based on its nuclear morphology, whether it is a myelocyte, metamyelocyte, or a mature cell. Be sure you know the biochemical composition of the cytoplasmic granules of neutrophils (polymorphonuclear leukocytes), eosinophils, and basophils. The cells of the erythroid and myeloid series tend to be grouped in small foci and that within each group the cells tend to be at the same stage of development. What is the functional significance of the cytoplasmic staining affinities of the basophilic erythroblast, polychromatophilic erythroblast, normoblast and erythrocyte? Know the structure and function of the lymphoid tissues and organs: (including afferent and efferent flow and specialized vasculature) a. B cells (as well as monocytes, erythrocytes, granulocytes, and megakaryoctyes) remain in the bone marrow as they mature. Lymphatic vessels carry lymph fluid, which contains particulate matter and protein that escape from blood capillaries as well as ingested fats, microorganisms, and other antigenic material that penetrate epithelial surfaces. Lymph is filtered in lymph nodes and then returned to the circulation via the thoracic duct and the right lymphatic duct. H & E The tonsillar ring is located near the entrance of the throat and consists of the palatine tonsil (commonly known as "the tonsil"), the pharyngeal tonsil (commonly known as "adenoids”), and the lingual tonsil (on the posterior surface of the tongue) This is a section through the palatine tonsil. Notice the stratified squamous non-keratinized epithelium covering the free oropharyngeal surface of the tonsil. In the underlying lamina propria identify simple and branched epithelial crypts sectioned in different planes and representing tubular invaginations of the surface epithelium. The lining epithelium of the crypts may show evidence of keratinization or erosion and can be obscured when heavily infiltrated with lymphocytes. Between the crypts identify the masses of lymphoid tissue containing numerous individual lymphoid nodules. Identify the connective tissue septa that extend at intervals between the crypts and Crypt Germinal center divide the tonsil into lobules, each with an 41 individual crypt as an axis.
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