The process of providing care macotherapy buy doxycycline american express antimicrobial resistance and antibiotic resistance, usually during the acute to a patient or taking action to modify a phase of treatment generic doxycycline 100mg overnight delivery antibiotics for sinus infection necessary, in which steady-state symptom purchase doxycycline 100mg without a prescription infection humanitys last gasp, an effect, or a behavior. Types of -M - intervention can include crisis interven- tion, brief intervention, and long-term m aintenance dosage. Medication sons related to program operations, safety, used for ongoing treatment of opioid or treatment complianceófor example, addiction. An opioid ago- incident to withdrawal from the continuous nist medication derived from methadone or sustained use of opioid drugs. Type of fully or do not show an acceptable response addiction treatment, usually provided in to other addiction treatments. Program offering treatment services, including medical and the benefits of peer support to people who psychosocial services. Facility established as part Twelve-Step programs are one type of of, but geographically separate from, an mutual-help program. The most frequently used opioid displaces opioids from these receptors and agonist medication. Methadone is a synthet- can precipitate withdrawal, but it does not ic opioid that binds to mu opiate receptors activate the mu receptors, nor does it cause and produces a range of mu agonist effects the euphoria and other effects associated similar to those of short-acting opioids such with opioid drugs. Some pro- Dispensing of methadone at stable dosage grams use naloxone to evaluate an individ- levels for more than 21 days in the super- ualís level of opioid dependence. W ithdrawal comprehensive maintenance services (with symptoms evoked by naloxoneís antagonist medication and counseling in one or several interaction with opioids confirm an individ- mobile units) to more limited care, usually ualís current dependence. Other substances com- drawal from opioids to prevent drug monly used by people addicted to opioids relapse in selected, well-motivated patients. Some drugsóin particular, high-dose barbituratesóused in Glossary 289 -O- opioid agonist. Areas on cell surfaces in that normally are bound by opioid psy- the central nervous system that are activat- choactive substances and that blocks the ed by opioid molecules to produce the activity of opioids at these receptors with- effects associated with opioid use, such as out producing the physiologic activity pro- euphoria and analgesia. Drug that binds to, Mu and kappa opiate receptor groups prin- but incompletely activates, opiate receptors cipally are involved in this activity. Natural derivative of opium or syn- nist but, at increasing doses, does not pro- thetic psychoactive substance that has duce as great an agonist effect as do effects similar to morphine or is capable of increased doses of a full agonist. Opioid trexone, of individuals who are addicted to addiction is characterized by repeated self- opioids. Services may include medically supervised withdrawal and/or maintenance opioid addiction treatm ent. Dispensing treatment, along with various levels of of approved medication to prevent with- medical, psychiatric, psychosocial, and drawal and craving during the elimination other types of supportive care. Method of identify- and rehabilitation services or medication ing evidence of opioid and other psychoac- prescribed when necessary to alleviate the tive substance use and measuring the levels adverse medical, psychological, or physical of substances or medications in the body by effects. This term encompasses medically examining patient saliva for the presence supervised withdrawal, maintenance treat- and concentrations of identifiable drugs ment, comprehensive maintenance treat- and their metabolites. In most States, patient excep- withdrawal but not for ongoing mainte- tions are contingent on the approval of the nance pharmacotherapy. OxyContin is one of several as well as rights and responsibilities of prescription opioids increasingly obtained patients and treatment providers. Term applied to two lev- els of activity in addiction treatment: (1) a patient referral. Alternative to providing all social or political movement working for necessary treatment services and levels of changes in legislation, policy, and funding care at the program site by collaboratively to reflect patient concerns and protect their outsourcing some services to other settings rights (i. W hen a patient must obtain philosophy of substance abuse treatment comprehensive services in multiple settings, practice maintaining that patients should Glossary 291 treatment program staff members should psychotherapy. Treatment service provided arrange the referrals, monitor patient to patients in a comprehensive opioid treat- progress, and coordinate care. Process of and treats patients for diagnosed psychi- individualizing therapeutic resources to atric problems. Readmission usually is preceded by a (1) assessing, (2) selecting the most suitable review of the patientís records to determine treatment modality and site, and (3) identi- whether and how the individualís treatment fying the most appropriate services. Treatment of disease treatment medication continue to eliminate with prescribed medications. Breakdown or setback in a personís attempt to change or modify a particular prevalence. Number of cases of a disease in a behavior; an unfolding process in which the population, either at a point in time (point resumption of compulsive substance use is prevalence) or over a period (period the last event in a series of maladaptive prevalence). Prevalence rate is the fraction responses to internal or external stressors of people in a population who have a or stimuli. State in which a mental or physi- existing cases of the condition at a specified cal disorder has been overcome or a disease time and the denominator is the total process halted. Evaluation of within the context of a cooperative living program effectiveness based on compliance arrangement. A substance that affects combination of patient and program char- the mind, thoughts, feelings, and sometimes acteristics. Process of determining whether a assigned by the governor to exercise the prospective patient has a substance use dis- responsibility and authority within a State order before admission to treatment. Negative association attached to an observation of known presenting com- activity or condition; a cause of shame or plaints and symptoms that are indicators of embarrassment. Agent, drug, or medication that system sedating and tranquilizing proper- produces stimulation. An example is any of the benzodi- lant usually refers to drugs that stimulate azepines. Medically unsanctioned use referred to as substance abuse or of drugs by a person to relieve any of a dependence). Consequence (especially an or it can occur regularly and be associated adverse result) other than that for which a with medical and mental problems, often drug is usedóespecially the result pro- including tolerance and withdrawal. Process of provid- substances and continue on maintenance ing immediate assistance (as with an opioid medication while receiving other types of agonist) to eliminate withdrawal symptoms intervention as needed to resume primary and drug craving. Opioid addiction problems, language difficulties, ethnic and treatment medication dispensed to patients social attitudes, logistics (caring for chil- for unsupervised self-administration. Joining of patients and their treatment providers in an effec- treatm ent eligibility. Relative qualification tive collaboration to assess and treat of a prospective patient for admission to an patientsí substance use disorders. Consciously Federal guidelines are minimum require- designed social environment or residential ments and restrict admission to individuals treatment setting in which social and group who have been demonstrably dependent on processes are harnessed with treatment opioids for 1 year; however, certain high- intent. Treatment focuses on drug abstinence, coupled with social and treatm ent outcom es.
A progestin that inhibits hormone dependent tumor growth by inhibiting pituitary and adrenal steroidogenesis purchase doxycycline 200mg infection gums. Available forms: oral suspension 40 mg/ml; oral suspension (concentrated) 125 mg/ml; tablets 20 mg and 40 mg order doxycycline 100mg without prescription antibiotics during labor. Available forms: capsules (delayed release) 10 mg order doxycycline with a visa antibiotic 2 times a day, 20 mg and 40 mg; powder for oral suspension 20 mg/packet, and 40 mg/packet; tablets (delayed release 20 mg. The onset of drug is 1 hour, the peak is 30 minutes to 2 hours and the duration is less than 3 days. Nursing Considerations: Ampicillin esters, iron derivatives, Ketoconazole (Nizoral – antifungal) may cause poor bioavailability of these drugs because they need a low gastric pH for optimal absorption. Drug is unstable in gastric acid; less drug is lost to hydrolysis because drug increases gastric pH. Zegerid (Prilosec - antiulcer) powder for oral suspension should be taken on an empty stomach at least 1 hour before a meal. For children ages 1 month to 16 years for duodenal and gastric ulcers only, 2 mg to 4 mg/kg orally twice a day, up to 300 mg/day. Available forms are: granules (effervescent) 150 mg; infusion 1 mg/ml in 50 ml containers; injection 25 mg/ml; syrup 15 mg/ml; tablets 75 mg, 150 mg, and 300 mg; tablets (dispersible) 150 mg; tablets 25 mg and 150 mg. The oral route has a 1 hour onset with a peak of 1 – 3 hours and a duration of 13 hours. Compatible solutions include sterile water for injection, normal saline solution for injection, D5W, or lactated ringers injection. For hypersecretory conditions 282 such Zollinger Ellison syndrome, dilute with D5W or other compatible solution to no more than 2. Tell patient to dissolve 25 mg effervescent dose tablet in at least 5 ml of water and give with a dosing cup, medicine dropper, or oral syringe. Nursing Considerations: Interactions with Carbamazepine (Tegretol – anticonvulsant) - increased blood levels and increased risk of toxicity. Do not give within 2 hours of a meal; caution patient to avoid grapefruit juice during therapy. Tell patient not to take drug with fruit juice or to swallow the chewable tablets whole. Dosage of oral antidiabetic or insulin may need to be reduced because improved metabolic control may accompany weight loss. Tell him to distribute daily intake of fat, carbohydrate, and protein over three main meals. If a meal is occasionally missed or contains no fat, tell patient that dose of drug can be omitted. Artificially produced trans fatty acids are bad in any amount and saturated fats from animal products should be kept to a minimum. The best fats or oils rather, since they are liquid at room temperature, are those that contain the essential fatty acids, so named because without them we would die. Essential fatty acids are polysaturated and grouped into two families, Omega 6 and Omega 3. Seemingly, minor differences in their molecular structure make the two families act very differently in the body. While the metabolic products of Omega 6 promote inflammation, blood clotting, and tumor growth, the Omega 3 acids act entirely opposite. Although, we do need both Omega 3 and Omega 6, it is becoming increasingly clear that an excess of Omega 6 fatty acids can have dire consequences. Many scientists believe that a major reason for the high incidence of Heart Disease, Hypertension, Diabetes, Obesity, premature aging, and some forms of cancer is the profound imbalance between our intake of Omega 6 and Omega 3 fatty acids. The main sources of Omega 6 fatty acids are vegetable oils such as corn oil and soy oil, which contain a high proportion of linoleic acid. A high intake of fish has been linked to a significant decrease in age related memory loss and cognitive function impairment and a lower risk of developing Alzheimer’s disease. Researchers have used fish oil supplements to treat bipolar disease (manic-depressive illness) and schizophrenia. Studies have shown that children who regularly eat fresh, oily fish have a four times lower risk of developing asthma than do children who rarely eat such fish by reducing airway inflammation and responsiveness. Fish oils help maintain the elasticity of artery walls, prevent blood clotting, reduce blood pressure and stabilize heart rhythm. Fish oil supplementation may help prevent arrhythmias and sudden cardiac death in healthy men. Heart attack survivors taking supplemental fish oil markedly reduce their risk of another heart attack, a stroke, or death. It is estimated that 85% or more of people in the Western world are deficient in Omega 3 fatty acids and most get far too much of the Omega 6 fatty acids. The processing and packaging of the fish oil are crucial in determining its quality. Low quality oils may be quite unstable and contain significant amounts of mercury, pesticides, and undesirable oxidation products. High quality oils are stabilized with adequate amounts of Vitamin E and are packaged in individualized foil pouches to seal out all light and oxygen. Cod liver oil is extracted from cod liver and is an excellent source of Vitamin A and D. Fish oil supplementation does, however, lower blood concentrations of Vitamin E, so it is a good idea to take extra Vitamin E when adding fish oils to your diet. Fish oils speed up healing of ligament injuries by daily supplementation of fish oil which could be used to improve the healing of the ligaments by enhancing the entry of new cells into the wound area and by speeding up collagen synthesis. Atopic diseases (which are a form of 294 allergy) where the hypersensitivity reaction occurs at a location different from the initial contact point between the body and the offending agent, and it also can alleviate Raynaud’s disease (which is characterized by periods of disrupted blood flow to the fingers and sometimes toes, caused by exposure to cold and stress. Progesterone inhibits through positive feedback, the secretion of pituitary gonadotrophins, in turn, this prevents follicular maturation and ovulation or alternatively promotes it for the prime follicle. Occasionally noted with short-term dosage, frequently observed with prolonged high dosage. Assess for any thrombophlebitis, pulmonary embolism, cardiac, liver, or renal dysfunction, cerebral hemorrhage, breast or genital cancers 296 2. Gastric distress usually subsides after the first few cycles of the drug, report if these symptoms persist. Report any symptoms of thrombic disorders such as pains in the legs, sudden onset of chest pain, and shortness of breath or coughing. Report any yellowing of the skin or eyes, which may necessitate discontinuing the drug, evaluation of liver function tests, and possibly a dosage change. May worsen psychic depression; report any mental status changes and the circumstance of the depression 8. With diabetes may alter glucose levels and the dosage of diabetic medications may need changed. Report early symptoms of ophthalmic pathology, such as headache, dizziness, blurred vision, or partial loss of vision, and get a thorough eye pain. Stimulant laxatives: substances that chemically stimulate the smooth muscles of the bowel to increase contractions, (Bisacodyl, Cascara, Danthron, and Senna).
Peter watches the weather chan- nel and listens to the news before he ventures any distance from home and avoids driving if the radio reports any chance of inclement weather buy generic doxycycline 100 mg on-line antibiotics for sinus ear infection. He also worries about his health and often visits his doctor cheap doxycycline amex antibiotic resistance nature, complaining of vague symptoms purchase doxycycline 200 mg amex virus hitting schools, such as nausea, head- aches, and fatigue. Peter’s doctor suggests that his worry may be causing many of his physical problems. He tells Peter to fill out a cost/benefit analysis of his vulnerability schema, which you can see in Table 7-4. Table 7-4 Cost/Benefit Analysis of Peter’s Vulnerability Schema Benefits Costs I keep myself safe. I’m so concerned about getting hurt that I’ve never enjoyed things that other people do, such as skiing or taking trips abroad. I am more careful than most people about I worry so much about tomorrow saving for retirement. My doctor tells me that my worry probably harms my health more than anything else. Someone as entrenched as Peter in his vulnerability schema certainly isn’t going to give it up just because of his cost/benefit analysis. However, this analysis starts the ball rolling by showing him that his assumption is costing him big-time. Counting up control People who have an anxious control schema only feel comfortable when they hold the reins. They fear that others won’t do what’s necessary to keep the world steady and safe. Jeff takes pride in the fact that, although he asks for plenty, he demands more of himself than he does of his employees. Although known for productivity, his division is viewed as lacking in creativity and leads all others in requests for trans- fers. The real cost of Jeff’s control assumption comes crashing down upon him when, at 46 years of age, he suffers his first heart attack. Jeff has spent many years feeling stressed and anxious, but he never looks closely at the issue. Debating dependency People with a dependency schema turn to others whenever the going gets tough. Unfortunately, people with the anxious depen- dency schema often lose the people they depend on the most. At the beginning of their relationship, Dorothy was fond of Daniel’s constant attention. Today, he still calls her at work three or four times every day, asking for advice about trivia and sometimes seeking reassurance that she still loves him. Dorothy’s friends tell her that they aren’t sure that Daniel could go to the bathroom by him- self. After he quits sev- eral jobs because “they’re too hard,” Dorothy threatens divorce. Daniel finally sees a therapist who has him conduct a cost/benefit analysis of his dependency schema, as shown in Table 7-5. Chapter 7: Busting Up Your Agitating Assumptions 115 Table 7-5 Cost/Benefit Analysis of Daniel’s Dependency Schema Benefits Costs I get people to help me I never find out how to handle difficult problems, when I need it. I’m never lonely because I might drive my wife away if I continue to cling to I always make sure that I her so much. It makes life easier when Sometimes I’d like to take care of something, but I someone else takes care of think I’ll screw it up. Someone like Daniel is unlikely to give up his defective dependency assump- tion without more work than this. See the list of agitating assump- tions in the “Sizing Up Anxious Schemas” section, earlier in this chapter. If you haven’t already taken the Anxious Schemas Quiz in Table 7-1, do so now and look at your answers. Do you tend towards perfection, seeking approval, vulnerability, control, or dependency or maybe have a combination of these schemas? First, determine which schema applies to you; if the quiz shows that you suffer from more than one schema, select one. Then, using the format of Table 7-5, fill out all the benefits that you can think of for your anxious schema in the left-hand column. Refer to the cost/benefit analyses that Prudence, Peter, and Daniel (see Tables 7-3, 7-4, and 7-5, respectively) filled out earlier in the chapter. Seeking input doesn’t necessarily mean that you operate on the depen- dency assumption or that you’re overly dependent; sometimes you just need someone else’s perspective to see what your anxiety is costing you. When you’ve finished your cost/benefit analysis, take another look at each of the benefits. Ask yourself whether those benefits will truly disappear if you change your agitating assumption. Prudence the perfectionist believes that her income is higher because of her perfectionism, but is that really true? Many people report that they make far more mistakes when they feel under pressure. So, it’s probably not the case that perfectionists earn more money and make fewer mistakes. As often as not, they end up not doing as well as they could because their perfectionism leads them into making more mistakes. When you look carefully at your perceived benefits, you’re likely to find, like Prudence, that the presumed benefits won’t evaporate if you change your assumption. But she finds herself even more frightened and embarrassed when she’s required to present in class than if she took more risks earlier. If you’re going to give up your assumptions, you need to replace them with a more balanced perspective. Designing Calm, Balanced Assumptions So, do you think you have to be perfect or that everyone has to like you all the time? For example, it is nice when people like you, and it is nice to be in charge sometimes. Chapter 7: Busting Up Your Agitating Assumptions 117 The solution is to find new, balanced schemas that hold even greater truth, but old assumptions are like habits — they’re hard to break. In the following sections, we go over each of the assumptions and help you see how to develop an alternative, more reasonable assumption to replace your old one. Try using these reasonable, balanced perspectives to talk back to your agitating assumptions when they occur. Finally, once you develop a new assumption, try acting in ways that are consistent with that new belief. If you find that your agitating assumptions rule your life and cause you intense anxiety and misery, you may want to consult a professional psychologist or mental-health counselor. Sometimes anxiety does have a physical base, and your primary care doctor can give you a referral after physical causes have been looked into. Should you consult a professional, you’ll still find this book useful because most anxiety experts are familiar with the tools that we provide, and they’ll help you implement them.
Mark’s Hospital order genuine doxycycline line nti virus, London Poisons in small doses are the best medicines; and Children are not little adults but paediatricians useful medicines in too large doses are poisonous buy doxycycline 200 mg antibiotic beginning with c. Ltd purchase 100 mg doxycycline mastercard virus like chicken pox, London () Humbert Wolfe – English poet and critic The doctors are a frightful race. Leonard Williams – I can’t see how they have the face Harley Street physician and author to go on practising their base The crime of our civilisation is gluttony. Cursory Rhymes ‘Poems Against Doctors’ I John Wilson (Christopher North) Paul Hamilton Wood – – British cardiologist, London Scottish poet, essayist and critic. The best history taker is he who can best interpret Doctors are generally dull dogs. It is Maxwell Wintrobe – just as it was the ﬁrst time, I am always hearing voices. March · World Medical Association Francis BrettYoung – I will maintain the utmost respect for human life English novelist and physician from the time of conception. Half the patients who get you up in the middle of Declaration of Geneva () the night and think they are dying are suffering If at all possible, consistent with patient from wind! Bradley Remembers () freely given consent after the patient has been It was a son’s duty to see his father into the grave. London () Declaration of Helsinki () Henry Youngman – Almroth Wright – I was so ugly when I was born, the doctor slapped British immunologist, St. A one liner quoted in the British Press from this Microbial infections are conveniently divided into contemporary comedian at time of his death septicaemias and intoxications. In the case of the former the bacteria multiply freely in the blood and produce their poisons there. New York Times Magazine October () Zeta (Sir (Vincent) Zachary Cope –) Carl August Wunderlich – Surgeon, St. Mary’s Hospital, London German Professor of Medicine, Leipzig The diagnostic problem of to-day Latter-day medicine recognises its tasks and its Has greatly changed—the change has come to duties as part of the immeasurably extensive and stay; sublime science of nature. We know in addition We all have to confess, though with a sigh that genuine facts and trustworthy data are solely On complicated tests we much rely attainable by means of the strictest attention to And use too little hand and ear and eye. Lewis () continually bearing in mind the possible sources Acute abdominal disease of fallacy. Is sometimes diagnosed with ease Vienna and Paris Concluding paragraphs () But oft the best attempts will meet A knowledge of the course of temperature in With sad and sorrowful defeat. Not every acute abdomen requires Preface to Medical Thermometry and Human Temperature Immediate operation for its cure (1871) And each good surgeon eagerly desires To make the needs for operation fewer. Mozon, California, June () To the average professional ofﬁcer, the military doctor is an unwillingly tolerated noncombatant who takes sick call, gives cathartic pills, makes transportation troubles, complicates tactical Yiddish proverb plans, and causes the water to smell bad. A cross-sectional, correlational non-experimental study was conducted with a convenience sample of 80 Black women who were taking antihypertensive prescription medications for blood pressure control. Almost one-third 30% (n=24) of the participants reported household incomes levels at or below the federal poverty level. The majority of the sample was employed (67%), physically inactive (90%), overweight/obese (88%), and had a history of smoking (54%). The study results did not show a difference between those who adhere to antihypertensive medications and those who do not. Also, there was no relationship between reactant behaviors and medication adherence. However, in the optimal predictive model, those aged 40-49 were less likely to be adherent to their antihypertensive medications. Trust in the health care provider was highly associated with adherence to the medication treatment regimen. These results are congruent with the expectation that trust in the health care provider promotes better medication adherence. Abel A Dissertation Submitted to the Faculty of The Graduate School at The University of North Carolina at Greensboro in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy Greensboro 2011 Approved by ____________________________________ Committee Chair © 2011 Willie M. Abel Without God I could do nothing, Without Him I would fail, Without Him my life would be rugged, Like a ship without a sail. To all who helped me in any way, thank you, especially the professors who taught me how to approach my work as a nurse scientist and my cohort/fellow PhD students who knowingly and unknowingly inspired me to work hard to succeed. A loving thank you I give to my husband, Kenneth, for his never ending love, support, encouragement, patience, and prayers during this endeavor. Special thanks to my mother, Virginia, for believing in me and keeping me lifted up in prayer. I thank all my family (including my church family) and friends for prayers and moral support. To all the women who participated in my study, I offer kind regards and blessings for their willingness to share in the research process. Exact Discrete-Event Model (Proportional Odds) for Compliance Scale from High (33) to Low (9)................................................................. More importantly, the reasons for not participating are not fully understood (Benjamin et al. Though a shorter life expectancy is troubling, morbidity and disability present a unique set of problems such as increased health care costs. Although not implicit, the factors related to antihypertensive medication nonadherence in Black women include the multifaceted nature of historical and socioeconomic determinants such as coping with multiple stressors, perceived racism, (Webb & Gonzalez, 2006), lower education, divergent health beliefs, inadequate lifestyle modifications, poor social support, alcohol and illicit drug use, medication side effects, cost factors, lack of health insurance, lack of access to care (Fongwa et al. However, the multifaceted nature of this problem creates a complexity that may be more individualistic in nature whereby one intervention strategy may not fit the majority of this population. Over time, damage to arterial walls and diminished blood supply cause destructive effects to major body systems such as the heart, kidney, and brain (Chobanian et al. Because of the critical need to reduce health disparity for Blacks and improve cardiovascular health, Healthy People 2010 objectives underwent revisions for Healthy People 2020. However, of particular interest is one new objective for Healthy People 2020 that focuses on medication adherence. However many third party payers will not pay for combination medications that are not available in the generic form because the cost is higher than reimbursing for two generic medications (Chobanian et al. One of the most intriguing reasons for nonadherence in Blacks stems from their historical beginnings within the United States healthcare system. Introduced to this country as slaves, Blacks were marketed as property with little to no human rights. They were frequently used in medical experiments by White doctors to perfect their technique before attempting procedures on those who were White (Gamble, 1997; Spillers, 1987; Washington, 2006). Because of skin color and other distinctive features such as hair texture, thick lips, and body shape, the lives of Blacks were not valued, and their exploitation by White physicians endured a long history (Gamble, 1997; Spillers, 1987; Washington, 2006). As a result, perceived stereotypes and prejudices experienced by Blacks in the health care arena have resulted in mistrust, refusal of treatment, and/or poor adherence with treatment regimens by Blacks (Gamble, 1997; "Unequal treatment", 2002).
Only in the sinusoidal capillaries of the liver order genuine doxycycline on line antibiotics for sinus infection dose, spleen and bone marrow can “pores” (so-called fenestrae) be found best purchase doxycycline antibiotics for sinus infection contagious. In the lining of these capillaries the basal membrane is fragmented or even completely missing purchase doxycycline with amex antibiotic groups. This anatomical information has important implications for the rational design of targeted carrier systems. If a therapeutic target is located outside the blood circulation and if normal anatomical conditions exist around the target site, a small-sized macromolecular carrier must be selected, in order to achieve 110 sufficient “escaping tendency” from the blood circulation. Particulate carriers will generally fail to extravasate, simply because there is no possibility for endothelium penetration. In addition to the issue of endothelial permeability, the effect of macrophages in direct contact with the blood circulation (e. Kupffer cells in the liver) on the disposition of carrier systems must be considered. Unless precautions are taken, particulate carrier systems are readily phagocytosed by these macrophages and tend to accumulate in these cells. Particle charge For liposomes, it has been shown that negatively charged vesicles tend to be removed relatively rapidly from the circulation whereas neutral vesicles tend to remain in the circulation for longer periods. Surface hydrophobicity Hydrophobic particles are immediately recognized as “foreign” and are generally rapidly covered by plasma proteins known to function as opsonins, which facilitate phagocytosis. The extent and pattern of opsonin adsorption depends highly on surface characteristics such as charge and hydrophilicity. A further consideration is that under pathological conditions, endothelium exhibits modified characteristics. For example, the endothelial fenestrations in inflammation sites can be as large as 0. However, in this case, the pattern is not uniform and depends on the tumor type and stage of development. Even within one 111 tumor, highly permeable sites can be identified in close proximity to sites of low permeability. Consequently, the major organs of accumulation are the liver and the spleen, both in terms of total uptake and uptake per gram of tissue. After phagocytosis, the carrier and the associated drug are transported to lysosomes and the drug is released upon disintegration of the carrier in this cellular compartment. If the drug is not broken down by the lytic enzymes of the lysosomes, it may be released in its active form from the lysosomal compartment into the cytoplasm and may even escape from the phagocyte, so causing a prolonged release systemic effect. Technology is available to reduce the tendency of macrophages to rapidly phagocytose colloidal drug carrier complexes. The process of “steric stabilization” involves the coating of the delivery system with synthetic or biological materials, which make it energetically unfavorable for other macromolecules to approach. This repulsive steric layer reduces the adsorption of opsonins and consequently slows down phagocytosis. This form of passive targeting, also called “selective targeting”, requires two conditions to be satisfied: • The size of the drug-carrier system should exceed the size of normal endothelial fenestrations to ensure that the carrier system only crosses inflamed endothelium; a certain size range is preferred as there is an upper limit to the endothelial fenestration dimensions under pathological conditions. If the circulation time is sufficiently prolonged and the particle size does not exceed, say, 0. Thus delivery systems designed for active targeting are usually composed of three parts: the carrier, the homing device and the drug (Table 5. Preferably, the homing device is covalently attached to the carrier, although successful targeting attempts of non-covalently attached homing device-carrier combinations have also been described. A list of cell-specific receptors and their corresponding ligands, expressed under physiological conditions, is presented in Table 5. Thus, for example, galactose can be used to target a drug carrier to parenchymal liver cells, etc. In the future, it is expected that the rapidly growing field of genomics will be used to identify specific receptors for targeting purposes (see Chapter 15). Sometimes it is necessary for the carrier-bound drug to reach all target cells to be clinically successful, as is the case with antitumor therapy. Bystander effects occur when the targeted drug carrier reaches its target site, and released drug molecules also act on surrounding non-target cells. In other cases not all target cells have to be reached, as is the case, for example, for targeted gene delivery for the local production of a therapeutic protein. Antibodies raised against a selected receptor are extensively used as homing devices. Modern molecular biotechnology permits the production of large amounts of tailor-made material. The antigen binding site of IgG molecules represents the homing part, which specifically interacts with the target (cells, pathogens, tissue). The sites that are responsible for the pharmacological effects of IgG, such as complement activation and macrophage interaction, are located at the stem part of the Y. The rest of the molecule forms the connection between the homing device and the pharmacologically active sites and also contributes to the long blood circulation characteristics of the IgG molecule, which has an elimination half-life much greater than 24 h. Often, the full antibody molecule (Mw 150 kD) is not utilized for targeting, but the antigen binding domain carrying the Fab (Mw 50 kD) fragment, or even smaller fragments (single chain antibodies, Mw 25 kD) can be used. The present generation of murine monoclonal antibodies is now being replaced by humanized or human antibodies. Antibodies have received most attention as potential homing devices, but other potential candidates are emerging, in the cytokine and the growth hormone family and, finally, among the adhesion molecules that play a role in the homing of inflammatory cells to inflammation sites. Active targeting strategies for soluble carriers include attaching rather simple homing devices such as galactose, for targeting to liver parenchymal cells (see Table 5. However, a number of disadvantages are also associated with the use of soluble carriers: • Limited drug loading capacity: poor stoichiometry of drug to carrier limits the mass transport mediated by the drug carrier. Examples of toxins are ricin, diphtheria toxin and abrin, which are all glycoproteins. Their toxicity is based on their ability to block protein synthesis at the ribosomal protein assembly site. They are normally extremely toxic and not suitable for therapeutic purposes because they induce liver and vascular toxicity, even at low dose levels. Chain A (Mw 32 kD) blocks the ribosomal activity, and chain B (Mw 34 kD) is responsible for cell entry of the A chain. Unfortunately, studies completed so far show that the present generation of immunotoxins lack specificity and are also immunogenic; a major fraction still ends up in the liver and causes toxicity, and severe side- 116 Figure 5. Attempts are being made to reduce liver uptake, by blocking or removing certain ligands on the ricin molecule which recognize receptors on liver parenchymal cells. Here again, the emphasis is on the improvement in drug disposition conferred by the carrier and homing device, as well as the protection offered by the system against premature inactivation. The drug moiety can be bound via either a direct linkage, or via a short chain “spacer”. The spacer overcomes problems associated with the shielding of the drug moiety by the polymer backbone.
These observations could be interpreted to mean that the speciﬁc qnr protein ought to be found in this group of proteins doxycycline 100mg on-line virus yang menguntungkan. This search resulted in the ﬁnding in Shewanella algae of a gene identical to that found originally on a plasmid in K discount doxycycline online american express treatment for dogs cough. Test tube experiments showed doxycycline 100mg line antibiotics pharmacology, furthermore, that the qnrA- like protein inhibited the gyrase function. This probably leads to slower bacterial growth, but for the bacterium, this is better than to be killed by the quinolone. After deﬁning the concept of plasmid-borne quinolone resistance, and characterization of the qnrA gene, several resistance genes of this type have been found. At a food- mediated eruption of Shigella ﬂexneri infections in Japan in 2003, a plasmid-borne gene for quinolone resistance was found and named qnrS. Its corresponding amino acid sequence shows a 59% amino acid sequence identity with the corresponding sequence of qnrA. Still another transferable quinolone resistance gene qnrB was found in a clinical isolate of K. All these observations seem to mean that quinolone resistance will soon be very widespread. It should be added here that another type of plasmid-borne quinolone resistance has already been mentioned in Chapter 6. That was the mutationally changed enzyme of aminoglycoside acetyltransferase, in which spontaneous mutations had changed the substrate spectrum of the enzyme to include a quinolone, ciproﬂoxacin. That was a notable development under the intense increase in the medical use of ciproﬂoxacin: A single-function resistance enzyme crossed substrate group boundaries to become capable of mediating resistance to unrelated antimicrobial agents, one of which is fully synthetic and which has not been present in nature until its relatively recent medical use. Finding the qnr protein in human pathogens also demonstrates the efﬁciency of those genetic mechanisms transporting resistance genes horizontally over long biological distances. Those genetic transport mechanisms might also have been developed and selected for by our distribution of antibiotics (see Chapter 10). These drugs are now used less as antibacterial agents in urinary tract infections. Finally, nitroimi- dazoles, which have found use against the peptic ulcer bacterium Helicobacter pylori, are discussed. There is evidence to show that mycobacteria emerged from the soil to ﬁnd a niche ﬁrst infesting, then infecting, various mammals and birds. Mycobacterium bovis is a common animal pathogen affecting a variety of animals, including ruminants and primates. It has been speculated that the tuberculosis bacterium was intro- duced into humankind when humans domesticated cattle some 7000 years ago. The disease of tuberculosis has been rampant in Europe and North America for the past ﬁve centuries. During the seven- teenth and eighteenth centuries ‘‘the white plague’’ took the life of one in ﬁve humans in these parts of the world. In the years 1850–1950, before medical treatment was introduced, 1 billion persons are estimated to have died from the disease. The tuber- culosis bacterium turned out to be highly resistant to the ﬁrst selectively acting antibacterial agents, such as the sulfonamides and penicillin. However, a betalactam derivative, meropenem, has recently been shown to have an effect on M. As mentioned in Chapter 6, streptomycin was the ﬁrst selectively acting agent that could be used to treat tuberculosis. Instead, today four standard remedies are used in the treatment of tuber- culosis: rifampicin, isoniazid, pyrazinamide, and ethambutol. A few other drugs for the treatment of tuberculosis are also mentioned later in the chapter. The antibacterial treatment of tuberculosis takes a long time because of the growth properties of M. Because of this risk it becomes very important to treat the infection with several antibacterial agents given in combination at the same time. Random bacte- rial mutations leading to resistance to individual drugs occur infrequently during bacterial replication, approximately once in 105 to 108 replications, and the resistance mutations to dif- ferent drugs are unlinked. The number of bacilli in a patient, also with extensive disease, rarely exceeds 109, which means that the occurrence of multiresistant mutants is highly improbable. The combination of drugs then means that the multiplication of low mutational resis- tance frequencies results in a much lower risk for antibacterial resistance. Rifampicin With the example of many antibiotics found earlier in soil microorganisms, a group of compounds, the rifamycins (9-1), which have an antibacterial effect, were found at the end of the 1950s in the soil bacterium Streptomyces mediterranei. The structure of these compounds contains an aromatic ring system, naphtokinone, over which there is a long aliphatic carbon bridge. Rifampicin has a broad antibacterial spectrum, although gram-negative rods such as E. This is because the large molecule cannot very well penetrate the thick lipopolysacharide layer of these bacteria. Rifampicin is also very effec- tive against both gram-positive and gram-negative cocci and has found good use with severe and hard-to-handle staphylococcal infections. Also, with infectious meningitis caused by Neisseria meningitidis, rifampicin has found good use for both treatment and prophylaxis. This is a large and complex enzyme, which in bacteria comprises ﬁve peptide subunits, one of which occurs in a pair. The complete enzyme, the holoenzyme, is built of two alpha subunits, one beta subunit, one beta subunit, and one sigma subunit. The corresponding enzyme in mammalian cells does not bind rifampicin, which is then acting selectively on bacteria. The common occurrence of rifampicin resistance is explained partially by the nucleotide composi- tion of the beta subunit gene, which is unusually A-T rich, which makes it prone to spontaneous mutations. This resis- tance development threatens the treatment of tuberculosis, for which, as noted, rifampicin is a very important remedy. Resis- tance determination would otherwise be very difﬁcult to handle because of the very slow growth of the tuberculosis bacterium. These conditions of resistance necessitate the combination of rifampicin with other antibacterial agents in tuberculosis treat- ment, which has to continue for several months. The combination of several antibacterial agents means that the low frequencies of spontaneous mutations to resistance for each agent are multiplied by one another, resulting in a very low probability of simulta- neous mutation toward resistance to two or more antibacterial agents. Plasmid-Borne Resistance Transferable plasmid-borne resistance to rifampicin was long regarded as nonexistent. During the 1990s, however, integron cassettes (see Chapter 10) were observed to mediate rifampicin resistance in clinical isolates of, for example, Pseudomonas aerug- inosa and E. Integron-borne genes can transfer with trans- posons and with plasmids and then also horizontally between bacteria (see Chapter 10). Rifampicin resistance by ribosylation was ﬁrst characterized in the nontuberculous bac- terium Mycobacterium smegmatis, which is endogenously resistant to rifampicin. The ribosylating enzyme could be speculated to have evolved as a defense against rifamycins in the microbial world of soil. A variant of arr-1 with a very similar nucleotide sequence, arr-2, has been found as an integron cassette (Chapter 10) in pathogenic clinical isolates of P.
Jouw kennis van de Q-Trap 6500 heeft ervoor gezorgd dat we last-minute de overstap konden maken en dat we toch tijdig de validatiedata konden produceren purchase genuine doxycycline on line antibiotic 4 times daily. Je hebt er zeker aan bijgedragen dat er weer financieel draagvlak kwam voor vervolgonderzoek naar chlooramfenicol en de ß-lactamanalyse order 100mg doxycycline otc bacteria model. Ingrid buy generic doxycycline pills virus yugioh, bedankt dat je er altijd bent om even 341 inhoudelijk mee te sparren en om af en toe wat persoonlijke zaken te bespreken. Hoe eenvoudig deze gesprekken misschien lijken, ze helpen wel om zaken wat te relativeren. Echt heel fijn om jou als collega te hebben en top dat jij als routinier paranimf wilt zijn. Ook jij bedankt dat je de proefversie van dit proefschrift hebt gecontroleerd; knap dat je nog zoveel kleine inconsistenties en taalfoutjes hebt weten te vinden. Sinds ik erachter kwam dat we zelf ook een Streptomyces venezuelae kunnen opkweken, hebben jullie je enorm flexibel opgesteld (een preparaat stond klaar wanneer ik maar wilde) en waren jullie enorm betrokken bij het onderzoek. Toch jammer dat het zo verdomd lastig is ervoor te zorgen dat die bacterie chlooramfenicol gaat produceren. Ooit gaat het ons lukken… Het is erg leuk om met jullie samen te werken, juist omdat onze achtergronden zo verschillend zijn. Mede daardoor ga ik iedere dag (nou ja, bijna iedere dag) met plezier naar mijn werk. Iedereen is altijd bereid om bij te springen waar nodig en o klaren we met ’n allen toch steeds weer iedere klus. Ook wil ik alle studenten bedanken die een bijdrage hebben geleverd aan het werk in dit proefschrift. Jullie hebben met ’n allen o ont ettend veel werk verzet dat ik niet anders kan dan concluderen dat dit proefschrift zonder jullie een stuk dunner was geweest. Ik heb het altijd leuk gevonden jullie te begeleiden en te zien hoe jullie je ontwikkelden. Richetti, bedankt voor het uitzoeken van goede condities om die nare chlooramfenicolisomeren op de chirale kolom te scheiden. Vooral de reproduceerbaarheid viel in het begin nogal tegen, maar het is toch gelukt. Cynthia, super dat je de methode voor de analyse van ceftiofur met behulp van de hydrolyse met ammoniak hebt geoptimaliseerd. Later is weliswaar overgestapt op piperidine, maar jij hebt de basis van de monstervoorbewerking. Sven, bedankt voor het implementeren van de verschillende methodes voor de analyse van ceftiofur en de analyse van al die vleesmonsters. Mathilde, bedankt voor het onderzoek naar de invloed van de 342 Dankwoord maalprocedure op de vorming van degradatieproducten van ceftiofur. Hoewel jouw werk niet direct in dit proefschrift is opgenomen (ik zou het misschien nog eens moeten publiceren), vormt het wel een heel belangrijke basis van het onderzoek. Ik ben blij dat je hebt kunnen aantonen dat er wel degelijk metabolieten gevormd worden na injectie van kippen met ceftiofur. Jouw werk vormde een mooie basis om de uiteindelijk gerapporteerde methode op te zetten. Het was een enorme klus: ik denk dat het je nog steeds duizelt als je bedenkt dat je meer dan 15000 pieken hebt geïntegreerd gedurende je stage. Ik schrik er elf een beetje van… In dit dankwoord uiteraard ook een mooie plek voor Freek. Iedereen weet wel dat dat niet waar is, maar uiteraard houd ik dat gerucht graag in stand. Met name tussen 2008 en 2010, de jaren waarin ik hele avonden en weekenden heb gestudeerd, heb jij alle andere taken uit handen genomen, zodat ik me op mijn opleiding kon concentreren. Hele weekenden zat ik opgesloten in de voorkamer te werken en ik heb jou daar niet één keer over horen mopperen. Hetzelfde geldt voor de laatste fase van mijn PhD: ik kon me volledig focussen op mijn proefschrift, omdat jij altijd voor me klaar staat en me steunt. Als ik na mijn promotie in het bekende zwarte gat val, zal ik jullie allemaal weer wat vaker gaan vervelen. Hoewel, de puzzel die ik van Sinterklaas heb gekregen met duizend stukjes uitsluitend grijskleurige olifant houdt me nog wel even van de straat (moet ik dat als subtiele hint van Sinterklaas beschouwen? Bjorn 343 344 Curriculum Vitae th Bjorn Berendsen was born on the 10 of March 1978 in Bemmel, The Netherlands. He started his Bachelor study, Higher Laboratory Education, at Hogeschool van Arnhem en Nijmegen. Nielen, The occurrence of chloramphenicol in crops through the natural production by bacteria in soil, J. Nielen, Comprehensive analysis of ß-lactam antibiotics including penicillins, cephalosporins and carbapenems in poultry muscle using liquid chromatography coupled to tandem mass spectrometry, Anal. Nielen, The (un)certainty of selectivity in liquid chromatography tandem mass spectrometry, J. Nielen, Assessment of liquid chromatography–tandem mass spectrometry approaches for the analysis of ceftiofur metabolites in poultry muscle, Food Add. Nielen, Quantitative trace analysis of eight chloramphenicol isomers in urine by chiral liquid chromatography coupled to tandem mass spectrometry, J. Nielen, Discrimination of eight chloramphenicol isomers by liquid chromatography tandem mass spectrometry in order to investigate the natural occurrence of chloramphenicol, Anal. Elliott, Evidence of natural occurrence of the banned antibiotic chloramphenicol in herbs and grass, Anal. Stolker, Newly identified degradation products of ceftiofur and cephapirin impact the analytical approach for quantitative analysis of kidney, J. Stolker, Determination of the stability of antibiotics in matrix and reference solutions using a straightforward procedure applying mass spectrometric detection, Food Add. Van Rhijn, Residue analysis of tetracyclines in poultry muscle: Shortcomings revealed by a proficiency test, Food Add. Brinkman, Liquid chromatographic–tandem mass spectrometric determination of selected sulphonamides in milk, J. Berendsen, Polymyxin E-1 (colistin sulphate) (neuro-)intoxication in young ostriches (Struthio camelus spp. Course Advanced Chromatography, Wageningen University, Organic Chemistry, Wageningen, the Netherlands (2011). Symposium Recent Advances in Food Analysis, Institute of Chemical Technology, Prague, Czech Republic (2011). Training School for Advanced Residue Analysis: group A6 antibiotics, Cochin, India.