By Q. Ballock. American University.
Risk of heart failure in patients with recent-onset type 2 diabetes: population-based cohort study buy fenofibrate 160mg. Comparison of extended-release metformin in combination with a sulfonylurea (glyburide) to sulfonylurea monotherapy in adult patients with type 2 diabetes: a multicenter buy cheap fenofibrate 160mg on line, double-blind, randomized, controlled, phase III study. Medical therapy for diabetes is associated with increased use of lower endoscopy. Pharmacoepidemiology and Drug Safety (England) 2007;16(Nov). The effect of thiazolidinediones on bone mineral density in Chinese older patients with type 2 diabetes. Effects of rosiglitazone on fasting plasma fibroblast growth factor- 21 levels in patients with type 2 diabetes mellitus. Thiazolidinedione addition reduces the serum retinol-binding protein 4 in type 2 diabetic patients treated with metformin and sulfonylurea. Pioglitazone and risk of cardiovascular events in patients with type 2 diabetes mellitus: a meta-analysis of randomized trials. Thiazolidinediones and cardiovascular outcomes in older patients with diabetes. Case reports of suspected adverse drug reactions--systematic literature survey of follow-up. Vertebral fractures in males with type 2 diabetes treated with rosiglitazone. Chronic heart failure-related interventions after starting rosiglitazone in patients receiving insulin. Association between serious ischemic cardiac outcomes and medications used to treat diabetes. Effects of the long-acting human glucagon-like peptide-1 analog liraglutide on beta-cell function in normal living conditions. Effect of pioglitazone on energy intake and ghrelin in diabetic patients. Metabolic effects of pioglitazone in combination with insulin in patients with type 2 diabetes mellitus whose disease is not adequately controlled with insulin therapy: results of a six-month, randomized, double-blind, prospective, multicenter, parallel-group study. Coronary heart disease outcomes in patients receiving antidiabetic agents. Pharmacoepidemiology and Drug Safety (England) 2007;16(Jul). Reduced daily risk of glycemic variability: comparison of exenatide with insulin glargine. UNR Md Isa SH, Najihah I, Nazaimoon WMW, Kamarudin NA, Umar NA, Mat NH, et al. Improvement in C-reactive protein and advanced glycosylation end-products in poorly controlled diabetics is independent of glucose control. Diabetes Research & Clinical Practice 2006;72(1):48-52. Estimating the long-term cost- effectiveness of exenatide in the United States: an adjunctive treatment for type 2 diabetes mellitus. Bone fractures and hypoglycemic treatment in type 2 diabetic patients: a case-control study. Lipids behavior and adverse effects for oral antidiabetic agents in patients with Type 2 diabetes treated with sulfonylureas alone based on systematic review. Effects of thiazolidinediones on bone loss and fracture. Pioglitazone induces regression of coronary atherosclerotic plaques in patients with type 2 diabetes mellitus or impaired glucose tolerance: a randomized prospective study using intravascular ultrasound. Liraglutide (NN-2211) for type 2 diabetes: horizon scanning technology briefing (Brief record). Rosiglitazone effects on blood pressure and metabolic parameters in nondipper diabetic patients. Diabetes Research & Clinical Practice 2005;70(1):20-5. Comparison of bare metal stent with pioglitazone versus sirolimus-eluting stent for percutaneous coronary intervention in patients with Type 2 diabetes mellitus. Comparison of pioglitazone vs glimepiride on progression of coronary atherosclerosis in patients with type 2 diabetes: the PERISCOPE randomized controlled trial. Effect of rosiglitazone on the risk of myocardial infarction and death from cardiovascular causes (Provisional abstract). New England Journal of Medicine 2007;356(24):2457-2471. Efficacy and safety of sitagliptin monotherapy in Japanese patients with type 2 diabetes. Diabetes Research and Clinical Practice 2008;79(2):291-8. Pioglitazone reduces the necrotic- core component in coronary plaque in association with enhanced plasma adiponectin in patients with type 2 diabetes mellitus. Effects of exenatide on systolic blood pressure in subjects with type 2 diabetes. Do incretin-based therapies cause acute pancreatitis? Insulin and oral agents for managing cystic fibrosis-related diabetes. Effect of rosiglitazone versus insulin on the pancreatic beta-cell function of subjects with type 2 diabetes. The risk of developing coronary artery disease or congestive heart failure, and overall mortality, in type 2 diabetic patients receiving rosiglitazone, pioglitazone, metformin, or sulfonylureas: a retrospective analysis. Rosiglitazone in Canada: experience in clinical practice. Long-term effects of pioglitazone versus gliclazide on hepatic and humoral coagulation factors in patients with type 2 diabetes. Diabetes distress and its association with clinical outcomes in patients with type 2 diabetes treated with pramlintide as an adjunct to insulin therapy. Modeling determinants of treatment satisfaction and preference. The clinical implications of the CHICAGO study for the management of cardiovascular risk in patients with type 2 diabetes mellitus.
In these exceptional cases in which may not be inhibited by high doses of heparin generic fenofibrate 160mg amex. If the polyspeciﬁc assay is positive discount fenofibrate 160mg otc, this may reveal the guide the laboratory evaluation of HIT. For the majority of patients presence of HIT IgA or IgM antibodies, which in some reports have with suspected HIT, the clinical evaluation combined with the been associated with HIT. In cases in which there is intermediate clinical suspicion and The majority of patients we evaluate fall into the “intermediate” immunoassays are not particularly helpful because of mixed sero- category (4Ts 4-5) of clinical suspicion for HIT. Serologic logic features (high polyclonal, but negative IgG or high IgG OD information (polyspeciﬁc vs IgG, OD, and a high heparin “conﬁrma- and negative excess heparin step), we send samples out for tory” step) and/or functional assay results are particularly helpful for functional assay testing. Historically, before the availability of the evaluation of this group of patients (Figure 2). A negative PF4/H immunoassays, functional assays were used routinely to immunoassay in a patient with intermediate clinical suspicion establish the presence of heparin-dependent antibodies. In func- virtually eliminates the possibility of HIT because of the high NPV tional assays, platelets from normal donors are incubated with of immunoassays. The posttest probability for this group of patients patient plasma in the presence of buffer or various doses of heparin is estimated at 0. The end point used for detecting platelet activation can vary. Functional end points of light transmission (platelet aggrega- by functional assay and/or evaluation of serologic features (IgG, tion or visualization of magnetic beads), release of radioactivity OD, or excess heparin) could further reﬁne the risk estimate for (platelets labeled with radioactive serotonin), or membrane activa- HIT. For instance, in a recent study by Nellen et al, patients were tion markers (ﬂow cytometry) are described in the literature. Additional investigations on the impact of 100%)30,31 and is heavily inﬂuenced by technical variables, includ- combining clinical suspicion with the various serologic variables ing baseline platelet reactivity and complexity of assay. For these (IgG isotype, OD, and high heparin) are likely to further clarify the reasons, functional assays are limited to major commercial laborato- utility of immunoassays and may even one day obviate the need for ries or referral laboratories at academic medical centers. The “ideal” assay for detecting HIT antibodies would combine the Management of the heparinized patient with sensitivity and technical feasibility of the immunoassays with the thrombocytopenia speciﬁcity of functional assays. Such hybrid assays are now in The management of patients suspected of HIT begins at the time of development. One recently described assay uses the expression of consultation, often long before results of laboratory testing are exogenous Fc RIIA receptors on lymphocytes32 and another mea- available (Figure 2). For patients with a low clinical suspicion of sures proteolysis of the Fc RIIA receptor33 as a surrogate marker HIT, we do not obtain testing and recommend continuation of for platelet activation. Both of these assays hold promise for heparin therapy. For patients with an intermediate or high clinical improving the speciﬁcity of and simplifying functional assays. Argatroban is the only nonheparin anticoagulant currently approved by the Food and Drug Administration for the Combining the clinical and laboratory evaluation treatment of HIT, but other agents such as bivalirudin and fondapa- Our approach to evaluating the thrombocytopenic patient for HIT rinux are increasingly used based on successful clinical experience. For dosing, and clinical experience of the nonheparin anticoagulants in patients with a low clinical suspicion of HIT, we do not recommend HIT. The reader is referred to recent excellent comprehensive testing due to the high negative predictive value (NPV) of scoring reviews on these topics. Studies have shown that patients with a high comorbidities and half-life considerations. We prefer to use paren- 4Ts score and a positive immunoassay have a posttest probability of teral direct thrombin inhibitors (DTI) in the critically ill patient, HIT approaching 100% (Table 1). We recommend judicious use of these alternative antico- immunoassays is high (false negative rate of 0. NPV 99%),22,34 in patients with high clinical suspicion, there If laboratory evaluation later reveals a low likelihood of HIT, we remains a quantiﬁable likelihood of HIT. In one study of 213 discontinue alternative anticoagulants and resume heparin therapy. Once the patient is anticoagulated on an alternative therapy antibodies to other related antigens, such as IL-8 or neutrophil and platelet counts have increased back to baseline, we initiate 672 American Society of Hematology warfarin therapy at a low dose (5 mg). Current guidelines recom- during cardiac surgery, however, is not trivial. At our institution, mend up to 4 weeks of anticoagulation with warfarin for patients some surgeons deem the bleeding risk unacceptable and will not with isolated HIT and a minimum of 3 months for patients with HIT perform surgery using DTIs. For these patients, management complicated by thrombosis. It should be noted that the use of plasmapheresis in HIT is not a categorized indication by the American Society of Apheresis. We bring attention to these questions not 2T32HL007057-36 and 1F32-AI108118-01 to G. Can PF4/H sensitized patients be exposed or ﬁnancial interests. Whether sensitized patients with or without HIT can receive future Correspondence heparin therapy is unresolved. Arepally, MD, Associate Professor, Medicine, Divi- guidelines advise limiting heparin reexposure in patients with a 1 sion of Hematology, Department of Medicine, Duke University history of HIT. The PF4/H immune response peaks between 5 and Medical Center, DUMC Box 3486, Room 301 Sands Building, 14 days after heparin exposure and wanes over time (120-360 16,38 Durham, NC 27710; Phone: 919-668-1550; Fax: 919-684-2420; days). In one case series, HIT patients were safely reexposed to e-mail: arepa001@mc. Treatment and become sensitized to heparin without developing HIT. Another unanswered question is whether these sensi- Guidelines. How I treat heparin-induced thrombocyto- subsequent heparin exposure. PF4/heparin-antibody complex induces monocyte tissue factor expression and release anticoagulation in patients with isolated of tissue factor positive microparticles by activation of Fcgam- thrombocytopenia in HIT? Patients with HIT and isolated thrombocytopenia are hypercoagu- 5. Is the incidence of lable and are at high risk for developing new thromboses ( 17%- 39,40 heparin-induced thrombocytopenia affected by the increased 53% over a 30-day period).
In trauma purchase fenofibrate 160mg overnight delivery, platelet count does strongly inﬂuence hemosta- Others have demonstrated rapid decrease in functional ﬁbrinogen sis and a low or decreasing platelet count in trauma patients does concentration and clot strength during hemorrhage and before ﬂuid predict greater mortality buy 160mg fenofibrate mastercard. During ﬁbrinolysis, tissue plasminogen activator (tPA) and the precursor plasminogen undergo high-afﬁnity Moderate or even mildly decreased platelet aggregation is strongly binding to ﬁbrin, where tPA activates plasminogen to plasmin. Kutcher et al used impedance aggregom- Plasmin then cuts ﬁbrin ﬁbers at speciﬁc lysine residues. As a result, etry to characterize platelet dysfunction in trauma patients on arrival the scaffold of the formed clot is rapidly degraded and the clot is at the emergency department. An increase in ﬁbrinolysis, known as hyperﬁ- almost half (45. It was described as a critical mechanism of action of TIC by acid (AA), and/or collagen. There was an astonishing 10-fold Brohi et al, who detected increased levels of tPA and the clot increase in mortality in patients having any one of these platelet breakdown product D-dimer. Solomon et tion and overt clot lysis by ROTEM in 303 trauma patients. They al showed similar results in 163 trauma patients of which 20 found that overt lysis was rare ( 5%), whereas moderate ﬁbrino- (12. They also found the platelet contribution in this cohort. In addition, those with ﬁbrinolytic activation demon- to clot ﬁrmness measured using rotational thromboelastometry strated higher mortality (12% vs 1%, P. ADP-induced platelet aggregation is mediated by a subgroup of nucleotide- The mechanism of hyperﬁbrinolysis in trauma is attributed to activated platelet receptors designated as P2T. Members of this activated protein C-mediated inactivation of plasminogen activator subgroup produce calcium inﬂux (P2X),17 inhibition of adenylyl inhibitor-1 (PAI-1), leaving tPA unchecked. Brohi et al have cyclase (P2T ),18 and mobilization of intracellular calcium stores provided evidence for this mechanism by demonstrating that AC through inositol phosphate production (P2T ),18 thus mediating activation of protein C by thrombin-thrombomodulin is associated PLC shape change, aggregation, and granule secretion. Activation of the with reduced PAI-1 concentration and elevated D-dimer. Therefore, common mecha- aPC on PAI-1, which has also been demonstrated in vitro. Further focused study is required to inhibiting thrombin-dependent PAI-1 degradation. Destruc- found elevated plasma syndecan-1 concentration in severely injured tion of PAI-1 via neutrophil elastase may also enhance ﬁbrinolysis trauma patients in hemorrhagic shock. In a smaller series of 57 trauma patients, Hayakawa et al proinﬂammatory cytokines, IFN- , IL-1 , and fractalkine, were found that those meeting the criteria for early DIC also displayed negatively associated with plasma syndecan-1 levels, presumably increased neutrophil elastase concentrations and neutrophil elastase- by their binding and activation of endothelium. These investigators speciﬁc ﬁbrin degradation products in addition to markers of then showed that endothelial barrier function was reduced in plasmin activation and tPA release on day 1 of treatment. Glycocalyx elastase can also degrade and inactivate PAI-1,31 so it may act shedding and associated loss of endothelial barrier function also similarly to the aPC system by altering PAI-1 availability during presumably promotes leukocyte recruitment and activation, libera- traumatic shock. Obviously, these data raise more questions than tion of injurious reactive oxygen species, and endothelial cell answers and further speciﬁc study of the mechanisms involved in damage, as demonstrated by the damaging effect of incubating hyperﬁbrinolysis during trauma are needed to reach deﬁnitive leukocytes captured from trauma patients on endothelial progenitor conclusions. Recent evidence points toward several interconnected from hemorrhagic shock. A multicenter retrospective study of over mechanisms, including anticoagulation by the thrombin-thrombo- 3646 trauma patients conﬁrmed that the severity of TIC is strongly modulin protein C system, platelet dysfunction, and hyperﬁbrinoly- associated with combined severe injury and shock. New evidence regarding the prominent role of inﬂammation and effect of materials released from tissue injury with inﬂammation endothelial activation/dysfunction as orchestrators of TIC continues and anticoagulant factors induced by endothelial injury and tissue to add to our understanding of this important and complex hypoxia likely mediate this relationship to produce TIC. Although our understanding of this disease has improved immensely in recent years, there remain many questions yet to be There is evidence that circulating intracellular contents such as answered. Kutcher et al examined plasma histone concentration in Disclosures 132 trauma patients on hospital arrival, ﬁnding a high degree of Conﬂict-of-interest disclosure: The author is on the board of circulating histone burden in patients with higher anatomical injury 33 directors or an advisory committee for Stasys Medical Corporation; severity. Increased histone concentration was present in patients has received research funding from the National Institutes of Health, with abnormal coagulation tests, increased markers of ﬁbrinolysis, the Department of Defense, the Wallace H. Rapid measurement of extracellular DNA levels the Washington State Life Sciences Discovery Fund; has consulted in the plasma of trauma patients also revealed a signiﬁcant elevation 34 for Stasys Medical Corporation; holds patents with or receives within 20 minutes of injury. In a small study of 37 multiple trauma royalties from Stasys Medical Corporation; and has equity owner- patients, patterns of elevated histones and extracellular DNA ship in Stasys Medical Corporation. Off-label drug use: None derived from activated neutrophils followed leukocyte counts, IL-6 disclosed. White, Harborview Medical Center, Emergency Dept, explain the critical role of anatomical injury severity in the Box 359702, 325 9th Ave, Seattle, WA 98104; Phone: 206-744- development of TIC. Neurohormonal and endothelial activation in response to acute References blood loss may also be involved in the development of TIC. Acute traumatic coagulopa- Johansson et al examined 75 victims of trauma and found that thy. Early coagulopathy in adrenaline concentration was signiﬁcantly elevated in nonsurvivors trauma patients: an on-scene and hospital admission study. Early evaluation of relationship may be mediated by products of endothelial or platelet acute traumatic coagulopathy by thrombelastography. Transl activation, such as soluble vascular endothelial growth factor Res. Brohi K, Cohen MJ, Ganter MT, Matthay MA, Mackersie RC, to be predictive of shock, coagulopathy, and mortality in trauma Pittet JF. Acute traumatic coagulopathy: initiated by hypoperfu- patients. Although speciﬁc mechanisms of shock-induced endothelial activa- 5. Acute coagulopathy of tion and dysfunction have not yet been elucidated, there is emerging trauma: hypoperfusion induces systemic anticoagulation and evidence that disruption of the endothelial glycocalyx barrier hyperﬁbrinolysis. Disseminated endothelial response to traumatic shock. Haywood-Watson et al intravascular coagulation or acute coagulopathy of trauma 662 American Society of Hematology shock early after trauma?
Metformin cheap 160mg fenofibrate visa, like all biguanides buy 160 mg fenofibrate with mastercard, can theoretically precipitate lactic acidosis and should thus be used with caution. Use of metformin should be avoided in patients with creatinine levels above 1. Surgical intervention (liposuction) for the treatment of local fat hypertrophy has been successfully performed, but appears to be associated with an increased risk of secondary infection (Guaraldi 2011), and recurrence of fat accumulation is possible. For the treatment of facial lipoatrophy, repeated subcutaneous injection of agents such as poly-L-lactic acid (Sculptra, New-Fill), a resorbable molecule that promotes collagen formation, has been effectively used in HIV+ patients (Casavantes 2004, Mest 2004, Behrens 2008). In 2004, Sculptra was approved by the FDA as an injectable filler to correct facial fat loss in people with HIV. We recommend consul- tation with experienced specialists for surgical treatments and injection therapy. Further evaluation in long-term follow-up studies is necessary to fully assess the value of these methods. We do not recommend the following drugs for HIV-related lipodystrophy: • The therapeutic intervention of recombinant human growth hormone (rHGH) (Serostim); the role of rHGH for HIV-associated fat accumulation has not been clearly defined. This therapy is very expensive and its only at best moderate effects disappear after stopping the treatment; there was rapid rebound of visceral fat to levels above baseline after treatment discontinuation (Grunfeld 2007, Lo 2008, Lo 2010). Management of Side Effects 295 Lifestyle changes Dietary interventions are commonly accepted as the first therapeutic option for hyperlipidemia, especially hypertriglyceridemia. Use of NCEP guidelines may reduce total cholesterol and triglycerides by 11 and 21%, respectively. Whenever possible, dietary restriction of total fat to 25–35% of the total caloric intake should be a part of any treatment in conjunction with lipid-lowering drugs. Consultation with pro- fessional and experienced dieticians should be considered for HIV+ patients and their partners. Patients with excessive hypertriglyceridemia (>1,000 mg/dl) may benefit from a very low fat diet and alcohol abstinence to reduce the risk of pancreatitis, especially if there is a positive family history or concurrent medications that may harbor a risk of developing pancreatitis. Regular exercise may have beneficial effects, not only on triglycerides and insulin resistance, but probably also on fat redistribu- tion (reduction in truncal fat and intramyocellular fat) and should be considered in all HIV+ patients (Driscoll 2004). All patients should be advised and supported to give up smoking in order to reduce cardiovascular risk. Cessation of smoking is more likely to reduce cardiovascular risk than any choice or change of ART or use of any lipid-lowering drug (Petoumenos 2010). Metabolic effects of darunavir/ritonavir versus atazanavir/ritonavir in treat- ment-naive, HIV type 1-infected subjects over 48 weeks AIDS Res Hum Retroviruses 2012, 28:1184-95. A randomized, pilot trial to evaluate glomerular filtration rate by creatinine or cystatin C in naïve HIV-infected patients after tenofovir/emtricitabine in combination with atazanavir/riton- avir or efavirenz. Barrios A, Garcia-Benayas T, Gonzalez-Lahoz J, et al. Treatment option for lipodystrophy in HIV-positive patients. Suspected drug-induced liver fatalities reported to the WHO database. Clinical Review : low body weight mediates the relationship between HIV infection and low bone mineral density: a meta-analysis. Risk factors for lactic acidosis in HIV-infected patients treated with nucleo- side reverse-transcriptase inhibitors: a case-control study. Adverse cutaneous reactions associated with the newest anti- retroviral drugs in patients with human immunodeficiency virus infection. Stevens-johnson syndrome associated with abacavir therapy. Relationship betwee renal dysfunction, nephrotoxicity and death among HIV adults on tenofovir. Management of hyperlactatemia: no need for routine lactate measurements. Recommendations for evaluation and management of bone disease in HIV. Fatal lactic acidosis and pancreatitis associated with ribavirin and didanosine therapy. Efficacy and tolerability of initial antiretroviral therapy: a systematic review. Carr A, Emery S, Law M, Puls R, Lundgren JD, Powderly WG. An objective case definition of lipodystrophy in HIV-infected adults: a case-control study. Fatal portal hypertension, liver failure, and mitochondrial dysfunction after HIV- 1 nucleoside analogue-induced hepatitis and lactic acidaemia. A syndrome of peripheral lipodystrophy, hyperlipidaemia and insulin resist- ance in patients receiving HIV protease inhibitors. Bio-Alcamid, a high-volume injectable posthesis for facial reconstruction in HIV- related lipoatrophy: a report on 100 patients. Reduced bone mineral density in HIV-infected patients: preva- lence and associated factors. Intracranial hemorrhage and liver-associated deaths associated with tipranavir/ritonavir: review of cases from the FDA’s Adverse Event Reporting System. Clinical management of treatment-experienced, HIV infected patients with the fusion inhibitor enfuvirtide: consensus recommendations. Cohen CJ, Andrade-Villanueva J, Clotet B on behalf of the THRIVE study group. Rilpivirine versus efavirenz with two background nucleoside or nucleotide reverse transcriptase inhibitors in treatment-naive adults infected with HIV-1 (THRIVE): a phase 3, randomised, non-inferiority trial The Lancet 2011: 378, 229 – 237. Adherence to antiretroviral therapy in managed care members in the United States: a retrospective claims analysis. Systematic review and meta-analysis: renal safety of tenofovir disoproxil fumarate in HIV-infected patients.
Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Year Control group Length of Country standard of care follow-up Cleland 2003 Yes 189 days (mean) Carvedilol Hibernating Reversible Ischaemia Trial: Marker of Success (CHRISTMAS) COPERNICUS Yes Mean 10 generic fenofibrate 160 mg with visa. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Year Randomization Allocation Similarity to target Country described? Carvedilol Heart Failure Study Group Anderson Inferior; pairs NR Yes Mean age 51 Screened: NR 1985 66% male Eligible: 50 Race NR Enrolled: 50 Waagstein Computer-generated NR Yes Mean age 49 Screened: NR 1993 with "block size of 4 cheap 160 mg fenofibrate mastercard," 73% male Eligible: 417 stratified Race NR Enrolled: 383 Beta blockers Page 271 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Eligibility Outcome Patient Year criteria assessors Care provider unaware of Country Exclusion criteria for recruitment specified blinded blinded treatment Hori Valvular heart disease, hypertrophic obstructive Yes NR NR NR 2004 cardiomyopathy, cardiogenic shock, systolic blood pressure < Japan 90 mm Hg, bradycardia (<60/min), grade II or III atrioventricular block, life-threatening arrhythmia, unstable The Multicenter angina, resting angina, cor pulmonale, asthma, Raynaud Carvedilol Heart Failure phenomenon, and intermittent claudication; myocardial Dose Assessment infarction or coronary artery bypass grafting had occurred (MUCHA) Trial within the preceding 3 months Packer 1996 Major CV event or surgical procedure within 3 months of study Yes Yes Yes Yes Colucci 1996 entry; uncorrected, primary valvular disease; active Yancy 2001 myocarditis; sustained ventricular tachycardia or advanced U. Carvedilol Heart heart block not controlled by antiarrhythmic intervention or a Failure Study Group pacemaker; systolic blood pressure of more than 160 or less than 85 mm Hg or diastolic blood pressure of more than 100 mm Hg; a heart rate of less than 68 beats per minute; clinically important hepatic or renal disease; or any condition other than heart failure that could limit exercise or survival; concomitant use of calcium-channel blockers α- or β-adrenergic agonists or antagonists or class IC or III antiarrhythmic agents Anderson Unstabilized overt cardiac failure; alcohol abuse; secondary Yes NR NR NR 1985 cardiomyopathies; firm exclusions to beta blocker treatment (asthma, advanced heart block, allergy) Waagstein Treatment with beta blockers, calcium channel blockers, Yes Yes NR NR 1993 inotropic agents or high doses of tricyclic antidepressant drugs; significant CAD shown by angiography; clinical or histological signs of ongoing myocarditis; other life-threatening diseases; obstructive lung disease; excessive alcohol consumption; drug abuse; insulin-dependent diabetes; pheochromocytoma; thyroid disease Beta blockers Page 272 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Maintenance of Reporting of attrition, Year Intention-to-treat (ITT) comparable crossovers, adherence, Loss to follow-up: Country analysis groups and contamination differential/high Score Funding Hori No (1 patient that did not NR No NR Fair NR 2004 received any medication No Japan was excluded from ITT) No No The Multicenter Carvedilol Heart Failure Dose Assessment (MUCHA) Trial Packer 1996 Yes NR AE withdrawals reported; none fair SmithKline Beecham Colucci 1996 others NR Pharmaceuticals and Roche Yancy 2001 Laboratories U. Carvedilol Heart Failure Study Group Two investigators/authors are employees and stock holders of SKB Anderson Yes NR Attrition=5/50(10%); others No Fair Univ. Foundation & Swedish Medical Research Council Beta blockers Page 273 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Year Control group Length of Country standard of care follow-up Hori Yes mean follow-up 2004 NR Japan The Multicenter Carvedilol Heart Failure Dose Assessment (MUCHA) Trial Packer 1996 Yes 12 months Colucci 1996 Yancy 2001 U. Carvedilol Heart Failure Study Group Anderson NR Mean 19 1985 months Waagstein NR 12 months and 1993 18 months (n=211/383) Beta blockers Page 274 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Year Randomization Allocation Similarity to target Country described? Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Eligibility Outcome Patient Year criteria assessors Care provider unaware of Country Exclusion criteria for recruitment specified blinded blinded treatment MERIT-HF Acute MI or unstable angina within 28 days; indication or Yes Yes NR NR contraindication for treatment with beta-blockade or drugs with Anonymous 1999 beta-blocking properties; heart failure secondary to systemic Goldstein 1999 disease or alcohol abuse; scheduled or performed heart Hjalmarson 2000 transplantation or cardiomyoplasty; implanted cardioversion Goldstein 2001 defibrillator (expected or performed); CABG or percutaneous Ghali 2002 transluminal coronary angioplasty planned or performed in the Gottlieb 2002 past 4 months; atrioventricular block of the second or third degree; unstable decompensated heart failure; supine systolic Metoprolol CR/XL BP >100 mm Hg; any serious disease that might complicate Randomised management and follow-up according to protocol; use of Intervention Trial in calcium antagonists; use of amiodarone within 6 months; poor Congestive Heart compliance. Failure Anonymous NR yes yes yes yes 2000 The Randomized Evaluation of Strategies for Left Ventricular Dysfunction Pilot Study (RESOLVD) Beta blockers Page 276 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Maintenance of Reporting of attrition, Year Intention-to-treat (ITT) comparable crossovers, adherence, Loss to follow-up: Country analysis groups and contamination differential/high Score Funding MERIT-HF Yes NR Attrition=589/3991 (15%); No Fair Project leader, coordinator, others NR medical advisor, and Anonymous 1999 acknowledgement to Astra Goldstein 1999 Hassle, Sweden Hjalmarson 2000 Goldstein 2001 Ghali 2002 Gottlieb 2002 Metoprolol CR/XL Randomised Intervention Trial in Congestive Heart Failure Anonymous yes NR Compliance (>80% of study NR Fair NR 2000 medication): met CR=93%; pla=92%; others NR The Randomized Evaluation of Strategies for Left Ventricular Dysfunction Pilot Study (RESOLVD) Beta blockers Page 277 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Year Control group Length of Country standard of care follow-up MERIT-HF Yes 1 year (mean) Anonymous 1999 Goldstein 1999 Hjalmarson 2000 Goldstein 2001 Ghali 2002 Gottlieb 2002 Metoprolol CR/XL Randomised Intervention Trial in Congestive Heart Failure Anonymous yes 24 weeks 2000 The Randomized Evaluation of Strategies for Left Ventricular Dysfunction Pilot Study (RESOLVD) Beta blockers Page 278 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Year Randomization Allocation Similarity to target Country described? Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Eligibility Outcome Patient Year criteria assessors Care provider unaware of Country Exclusion criteria for recruitment specified blinded blinded treatment Waagstein Coronary artery bypass grafting (CABG) or percutaneous yes NR NR NR 2003 transluminal coronary angioplasty (PTCA) within the previous Europe 6 months or who were scheduled for or expected to require these treatments during the 6-month study; patients who had a major ischemic event (acute MI or unstable angina) within the previous 6 months and those with large anterior aneurysms, acute myocarditis, primary valvular heart disease, exercise- limiting angina pectoris or severe systemic disease; excessive consumption of alcohol (≥ 100 g of pure alcohol/day or ≥ 700 gram/week), resting systolic blood pressure > 190 mmHg or diastolic > 100 mmHg, systolic blood pressure <95 mmHg (unless considered occasional), heart rate < 50 beats/min, second- or third-degree atrioventricular (AV) block, sick sinus syndrome, sinoatrial block or atrial fibrillation (which makes equilibrium radionuclide angiography difficult to perform; pacemaker for third-degree AV block or a ventricular inhibited (VVI) pacemaker programmed with a fixed heart rate above the spontaneous heart rate Edes Acute corinary syndrome; a MI within the last 3 months; PTCA yes stated double- stated double- stated double- 2005 or coronary artery bypass surgery within the last month; blind, but no blind, but no blind, but no (ENECA) obstructive or hypertrophic cardiomyopathy; hemodynamically details given details given details given relevant congenital or valvular heart disease; tachyarrhythmia resistant therapy (>100/min); bradycardia. Patients were also excluded if they received beta-blocker therapy in the 4 weeks prior to the beginining of the trial or known intolerance or hypersensitivity to nebibolol. Beta blockers Page 280 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Maintenance of Reporting of attrition, Year Intention-to-treat (ITT) comparable crossovers, adherence, Loss to follow-up: Country analysis groups and contamination differential/high Score Funding Waagstein no (4 patients excluded NR yes no Fair Medical Research Council 2003 from ITT due to never no no (Project 02529), the Swedish Europe taking study medication) no Heart-Lung Foundation and no AstraZeneca Edes yes yes yes no Fair Berlin-Chemie AG, Menarini 2005 no no Group, Berlin, Germany (ENECA) no no Beta blockers Page 281 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Year Control group Length of Country standard of care follow-up Waagstein Yes 6 months 2003 Europe Edes yes 12 months 2005 (ENECA) Beta blockers Page 282 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Year Randomization Allocation Similarity to target Country described? Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Eligibility Outcome Patient Year criteria assessors Care provider unaware of Country Exclusion criteria for recruitment specified blinded blinded treatment Flather New drug therapy for heart failure 6 weeks prior to yes NR NR yes 2005 randomization, any change in cardiovascular drug therapy 2 (SENIORS) weeks prior to randomization, heart failure due primarily to valvular heart disease, contraindication or previous intolerance to beta-blockers (e. Beta blockers Page 284 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Maintenance of Reporting of attrition, Year Intention-to-treat (ITT) comparable crossovers, adherence, Loss to follow-up: Country analysis groups and contamination differential/high Score Funding Flather analysis excluded 7 yes yes no Fair Menarini Ricerche SpA 2005 patients no no (SENIORS) yes no Beta blockers Page 285 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 10. Quality assessments of placebo-controlled trials of beta blockers for heart failure Author Year Control group Length of Country standard of care follow-up Flather yes mean 21 2005 months (SENIORS) Beta blockers Page 286 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 11. Head-to-head trials of beta blockers for heart failure Author Study Year Design Country Setting Eligibility criteria Exclusion criteria Sanderson RCT Patients with typical symptoms of heart failure and reduced LV Valvular heart disease as the etiology of LV dysfunction, active 1999 ejection fraction (<0. Head-to-head trials of beta blockers for heart failure Author Allowed other Age Year Interventions (drug, medications/ Method of outcome assessment Gender Country regimen, duration) interventions and timing of assessment Ethnicity Sanderson Metoprolol (met) 100 mg Frusemide Minnesota Heart Failure Symptom Mean age: met=60. Head-to-head trials of beta blockers for heart failure Number Number Author Other population screened/ Author withdrawn/ Year characteristics eligible/ Year lost to fu/ Country (diagnosis, etc) enrolled Country analyzed Sanderson Mean NYHA class: met=2. Head-to-head trials of beta blockers for heart failure Author Year Method of adverse effects Adverse effects Country Outcomes assessment? Head-to-head trials of beta blockers for heart failure Author Withdrawals due to Year adverse events (%, Country adverse n/enrolled n) Sanderson 1999 China Kukin NR 1999 Beta blockers Page 291 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 11. Head-to-head trials of beta blockers for heart failure Author Study Year Design Country Setting Eligibility criteria Exclusion criteria Metra RCT Patients with chronic heart failure caused by an ischemic or Patients with unstable angina, an acute myoardial infarction, or a 2000 nonischemic cardiomyopathy; NYHA class II, III, or IV coronary revascularization procedure within 3 months; history of alcohol symptoms for >/= 6 months; LV ejection fraction = 0. Head-to-head trials of beta blockers for heart failure Author Allowed other Age Year Interventions (drug, medications/ Method of outcome assessment Gender Country regimen, duration) interventions and timing of assessment Ethnicity Metra Weight <75 kg/Weight >/= Frusemide LVEF Age= met=58; car=55 2000 75 kg ACE inhibitor Bicycle exercise testing Gender(%male): Metoprolol tartrate (met): Angiotensin II 6-minute walk test met=90. Head-to-head trials of beta blockers for heart failure Number Number Author Other population screened/ Author withdrawn/ Year characteristics eligible/ Year lost to fu/ Country (diagnosis, etc) enrolled Country analyzed Metra Etiology NR/NR/150 Metra 28 withdrawn/0 2000 IDC(%): met=46(61. Head-to-head trials of beta blockers for heart failure Author Year Method of adverse effects Adverse effects Country Outcomes assessment? Head-to-head trials of beta blockers for heart failure Author Withdrawals due to Year adverse events (%, Country adverse n/enrolled n) Metra met=3; car=2 2000 Beta blockers Page 296 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 11. Head-to-head trials of beta blockers for heart failure Author Study Year Design Country Setting Eligibility criteria Exclusion criteria Metra RCT Patients with chronic HF caused by an ischemic or nonischemic Patients with an acute ischemic event or a coronary revascularization 2002 cardiomyopathy who had NYHA function II-IV symptoms, a procedure within 3 months; a history of alcohol abuse; primary valve USA, Italy LVEF =35% by radionuclide ventriculography, and ongoing disease or congenital heart disease; frequent ventricular premature treatment with furosemide and an ACEI beats and/or runs of ventricular tachycardia; contraindications to beta- blocker therapy; concomitant treatment with other beta-blockers, α- antagonists, calcium antagonists or antiarrhythmic agents (except amiodarone) Beta blockers Page 297 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 11. Head-to-head trials of beta blockers for heart failure Author Allowed other Age Year Interventions (drug, medications/ Method of outcome assessment Gender Country regimen, duration) interventions and timing of assessment Ethnicity Metra Weight <75 kg/Weight >/= Furosemide NYHA functional classification x 9- Mean age: met=60; 2002 75 kg ACE inhibitor 12 months car=56 USA, Italy Metoprolol tartrate (met): Gender(%male): 100/200 mg daily (n=17) met=17. Head-to-head trials of beta blockers for heart failure Number Number Author Other population screened/ Author withdrawn/ Year characteristics eligible/ Year lost to fu/ Country (diagnosis, etc) enrolled Country analyzed Metra Etiology NR/NR/34 Metra 29 analyzed 2002 IDC n(%): met=11(64. Head-to-head trials of beta blockers for heart failure Author Year Method of adverse effects Adverse effects Country Outcomes assessment? Head-to-head trials of beta blockers for heart failure Author Withdrawals due to Year adverse events (%, Country adverse n/enrolled n) Metra NR 2002 USA, Italy Beta blockers Page 301 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 11. Head-to-head trials of beta blockers for heart failure Author Study Year Design Country Setting Eligibility criteria Exclusion criteria Poole-Wilson RCT Men or women with symptomatic chronic heart failure (HYHA Recent change in treatment within 2 weeks before randomization; 2003/Cleland class II-IV); at least one cardiovascular admission during the requirement for intravenous inotropic therapy; current treatment with 2006/Torp- previous 2 years; on stable heart failure treatment with ACE non-dihydropyridine calcium channel blockers (diltiazem, verapamil); Pedersen inhibitors for at least 4 weeks unless contraindicated; on amiodarone (>200 mg per day); class-I antiarrhythmic drugs; unstable 2005/Torp- treatment with diuretics (≥40 mg of frusemide or equivalent) for angina; myocardial infarction; coronary revascularisation or stroke within Pedersen 2007 at least 2 weeks; LVEF = 35% measured within the previous 3 the previous 2 months; uncontrolled hypertension (SBP >170 mm Hg or Europe months by echocardiography or radionuclide ventriculography DBP >105 mm Hg); hemodynamically significant valvular disease; symptomatic and sustained ventricular arrhythmias within the past 2 Carvedilol Or months note adequately treatment with antiarrhythmic drugs or Metoprolol implantation of an automatic defibrillator; pregnancy; women with European Trial childbrearing potential on inadequate contraception; known drug or (COMET) alcohol misuse; poor compliance; any other serious systemic disease; contraindication to beta blockers Beta blockers Page 302 of 494 Final Report Update 4 Drug Effectiveness Review Project Evidence Table 11. Head-to-head trials of beta blockers for heart failure Author Allowed other Age Year Interventions (drug, medications/ Method of outcome assessment Gender Country regimen, duration) interventions and timing of assessment Ethnicity Poole-Wilson Carvedilol (car) 50 mg ACE inhibitor Follow-up visits at 4-month Mean age: 62 2003/Cleland Metoprolol (met) 100 mg x Diuretic intervals 79.
Long-term effects of two different continuous combined regimens of hormone replacement therapy on well-being fenofibrate 160mg low cost. Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology purchase 160 mg fenofibrate amex. Gordon SF, Thompson KA, Ruoff GE, Imig JR, Lane PJ, Schwenker CE. Efficacy and safety of a seven-day, transdermal estradiol drug-delivery system: comparison with conjugated estrogens and placebo. International Journal of Fertility & Menopausal Studies. Efficacy and tolerance of Menorest compared to Premarin in the treatment of postmenopausal women. A comparison of transdermal and oral HRT for menopausal symptom control. Quality of life assessment in a chemoprevention trial: fenretinide and oral or transdermal HRT. Comparison of a novel vaginal ring delivering estradiol acetate versus oral estradiol for relief of vasomotor menopausal symptoms. Endometrial and vaginal effects of low-dose estradiol delivered by vaginal ring or vaginal tablet. Climacteric : the journal of the International Menopause Society. Almeida OP, Lautenschlager NT, Vasikaran S, Leedman P, Gelavis A, Flicker L. A 20- week randomized controlled trial of estradiol replacement therapy for women aged 70 years and older: effect on mood, cognition and quality of life. Baksu A, Ayas B, Citak S, Kalan A, Baksu B, Goker N. Efficacy of tibolone and transdermal estrogen therapy on psychological symptoms in women following surgical menopause. International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics. Effects of genistein on hot flushes in early postmenopausal women: a randomized, double-blind EPT- and placebo-controlled study. Dayal M, Sammel MD, Zhao J, Hummel AC, Vandenbourne K, Barnhart KT. Supplementation with DHEA: effect on muscle size, strength, quality of life, and lipids. Effects of ultralow-dose transdermal estradiol on postmenopausal symptoms in women aged 60 to 80 years. The effect of hormone replacement on physical performance in community-dwelling elderly women. Hormone therapy Page 61 of 110 Final Report Update 3 Drug Effectiveness Review Project 32. Estrogen therapy selectively enhances prefrontal cognitive processes: a randomized, double-blind, placebo-controlled study with functional magnetic resonance imaging in perimenopausal and recently postmenopausal women. Levine DW, Dailey ME, Rockhill B, Tipping D, Naughton MJ, Shumaker SA. Newton KM, Reed SD, LaCroix AZ, Grothaus LC, Ehrlich K, Guiltinan J. Treatment of vasomotor symptoms of menopause with black cohosh, multibotanicals, soy, hormone therapy, or placebo: a randomized trial. Gabapentin, estrogen, and placebo for treating hot flushes: a randomized controlled trial. Estradiol and drospirenone for climacteric symptoms in postmenopausal women: a double-blind, randomized, placebo-controlled study of the safety and efficacy of three dose regimens. Climacteric : the journal of the International Menopause Society. Speroff L, Haney AF, Gilbert RD, Ellman H, Estradiol Acetate Investigator G. Efficacy of a new, oral estradiol acetate formulation for relief of menopause symptoms. Speroff L, Symons J, Kempfert N, Rowan J, femhrt Study I. The effect of varying low- dose combinations of norethindrone acetate and ethinyl estradiol (femhrt) on the frequency and intensity of vasomotor symptoms. The effect of ultralow-dose transdermal estradiol on urinary incontinence in postmenopausal women. Short-term transdermal estradiol therapy, cognition and depressive symptoms in healthy older women. A randomized placebo controlled pilot cross-over study. Effects of low-dose, continuous combined hormone replacement therapy on sleep in symptomatic postmenopausal women. Investigating the effects of estradiol or estradiol/progesterone treatment on mood, depressive symptoms, menopausal symptoms and subjective sleep quality in older healthy hysterectomized women: a questionnaire study. Estradiol or estradiol/progesterone treatment in older women: no strong effects on cognition. Do combinations of 1 mg estradiol and low doses of NETA effectively control menopausal symptoms? Bech P, Munk-Jensen N, Obel EB, Ulrich LG, Eiken P, Nielsen SP. Combined versus sequential hormonal replacement therapy: a double-blind, placebo-controlled study on Hormone therapy Page 62 of 110 Final Report Update 3 Drug Effectiveness Review Project quality of life-related outcome measures. Cardiovascular risk factors and combined estrogen-progestin replacement therapy: a placebo-controlled study with nomegestrol acetate and estradiol. Quality of life during sequential hormone replacement therapy -- a placebo-controlled study. International Journal of Fertility & Menopausal Studies. Estrogen raises the sweating threshold in postmenopausal women with hot flashes. Dose-response and withdrawal effects on climacteric symptoms after hormonal replacement therapy.
Thiswell-studied vi- rus illustrates how one can measure multiple selective forces on partic- ular amino acids purchase 160 mg fenofibrate mastercard. Selective forces on amino acids in viral surface mole- cules include altered binding to host-cell receptors and changed binding to host antibodies cheap fenofibrate 160 mg otc. The selective forces imposed by antibodies and by at- tachment to host-cell receptors can be varied in experimental evolution studies to test their eﬀects on aminoacidchange in the parasite. The amino acid substitutions can also bemapped onto three-dimensional structural models of the virus to analyze how particular changes alter binding properties. Chapter 13 continues with experimental evolution of inﬂuenza A vi- ruses. Experimental evolution has shown how altering the host species favors speciﬁc amino acid changes intheinﬂuenzasurface protein that binds to host cells. Experimental manipulation of host-cell receptors and antibody pressure can be combined with structural data to under- stand selection on the viral surface amino acids. These mechanistic analyses of selection can be combined with observations on evolution- arychange in natural populations to gain a better understanding of how selection shapes the observed patterns of antigenic variation. The host T cells can potentially bind to any short peptide of an intracellular parasite, whereas antibodies typically bind only to the surface molecules of parasites. T cell binding to parasite peptides depends on a sequence of steps by which hosts cut up parasite proteins and present the resulting peptides on the surfaces of host cells. Para- site escape from T cell recognition can occur at any of the processing steps, including the digestion of proteins, the transport of peptides, the binding of peptides by the highly speciﬁc host MHC molecules, and the binding of peptide-MHC complexes to receptors on the T cells. One or two amino acid substitutions in a parasite protein can often abrogate binding to MHC molecules or to the T cell receptors. Experimental evo- lution has helped us to understand escape from T cells because many of the steps can be controlled, such as the MHC alleles carried by the host and the speciﬁcities of the T cell receptors. Parasite proteins may be shaped by opposing pressures on physiological performance and es- cape from recognition. Chapter 15 turns to samples of nucleotide sequences from natural populations. A phylogenetic classiﬁcation of sequences provides a his- torical reconstruction of evolutionary relatedness and descent. Against the backdrop of ancestry, one can measure how natural selection has changed particular attributes of parasite antigens. For example, one can study whether selection caused particular amino acids to change rapidly or slowly. The rates of change for particular amino acids can be com- pared with the three-dimensional structural location of the amino acid site, the eﬀects on immunological recognition, and the consequences for binding to host cells. The changes in natural populations can also be compared with patterns of change in experimental evolution, in which one controls particular selective forces. Past evolutionary change in pop- ulation samples may be used to predict which amino acid variants in antigens are likely to spread in the future. The last chapter recaps some interesting problems for future research that highlight the potential to study parasites across multiple levels of analysis. PART I BACKGROUND Vertebrate Immunity 2 “The CTLs destroy host cells when their TCRs bind matching MHC-pep- tide complexes. I had initially intended this book to avoid such jargon, so that any reasonably trained biologist could read any chapter without getting caught up in technical terms. I failed— the quoted sentence comes from a later section in this chapter. The vertebrate immune system has many specialized cells and mole- cules that interact in particular ways. One has to talk about those cells and molecules, which means that they must be named. I could have tried a simpler or more logically organized naming system, but then I would have created a private language that does not match the rest of the literature. In this chapter, I introduce the major features of immunity shared by vertebrates. I present enough about the key cells and molecules so that one can understand how immune recognition shapes the diversity of parasites. I have not attempted a complete introduction to immunology, because many excellent ones already exist. I recommend starting with Sompayrac’s (1999) How the Immune System Works,whichisashort, wonderfully written primer. One should keep a good textbook by one’s side—I particularly like Janeway et al. Mims’s texts also pro- vide good background because they describe immunology in relation to parasite biology (Mims et al. The ﬁrst section of this chapter describes nonspeciﬁc components of immunity. Nonspeciﬁc recognition depends on generic signals of par- asites such as common polysaccharides in bacterial cell walls. These signals trigger various killing mechanisms, including the complement system, which punches holes in the membranes of invading cells, and the phagocytes, which engulf invaders. The second section introduces speciﬁc immunity, the recognition of small regions on particular parasite molecules. Speciﬁc recognition oc- curs when molecules of the host immune system bind to a molecular shape on the parasite that is not shared by other parasites. Sometimes all parasites of the same species share the speciﬁcity, and recognition 14 CHAPTER 2 diﬀerentiates between diﬀerent kindsofparasites. Other times, diﬀer- ent parasite genotypes vary in molecular shape, so that the host mole- cules that bind speciﬁcally to one parasite molecule do not bind another parasite molecule that diﬀers by as little as one amino acid. A parasite molecule that stimulates speciﬁc recognition is called an antigen. The small region of the parasite molecule recognized by the host is called an epitope. Antigenic variation occurs when a speciﬁc immune response against one antigenic molecule fails to recognize a variant antigenic mol- ecule. The third section presents the B cells, which secrete antibodies.