Molecular and Medical Parasitology Leistungsnachweise (9 LP)
Transcription
Molecular and Medical Parasitology Leistungsnachweise (9 LP)
Molecular and Medical Parasitology Mosquito feeding on human blood Leishmania amastigotes bursting from a macrophage 1 Leistungsnachweise (9 LP) • Klausur (4 LP) – 2 Stunden – Format: 10-14 Fragen • Praktikumsprotokoll (2 LP) – Gruppenprotokoll (2 Studenten/Gruppe) • Seminarvortrag (3 LP) 2 1 Seminars What do I expect? • Two meetings with me (Starting literature & final check) • 20-25 min Powerpoint presentation • Printed reference list on the day of the seminar • One question relating to each seminar (relevant for exam) Content? • Address your fellow students! • Thorough introduction • Use of research papers (not just internet resources) • German or English (English highly recommended) Marking? • Style and content! 3 Some hints for a good presentation • About 1 (or less) slide/minute • Make slides simple • Textbook figures are often too complex • Use illustrations rather than text • Use good quality images (sufficient resolution) • Don’t do jokes (unless you are really good at it) • See “Genetik” Teaching Website for more infos 4 2 The microtubule system Centrosome 5 Microtubules in Mitotic cell Chromosomes Centrosome Mitotic Spindle Centrosome 6 3 Molecular and Medical Parasitology SS2014 Seminars Name Thema des Vortrags Wolter, Madita Weisert, Nadine Simmler, Julia Schrüfer, Sebastian Schöps, Anna-Lena Schmidt, Stefanie Schließner, Marcel Schirber, Fabian Schalles, Simone Reichert, Anja Priesnitz, Chantal Newald, Josephine Misun, Jan Michalski, Marlen The molecular biology of life cycle differen4a4on in T. brucei Development of Trypanosoma brucei in the tsetse fly How does Trypanosoma cruzi survive inside the host cell? How does Leishmania survive inside the host cell? The role of mosquitoes in the transmission of infec4ous diseases Transgenic mosquitos to control vector popula4ons Sexual differen4a4on in malaria parasites The current status of malaria vaccina4on The current status of malaria chemotherapy Hemoglobinopathies and protec4on from malaria Func4on of Toll-‐like receptors in the immune response against infec4ons Metabolic adapta4ons of parasites Tapeworm genomes and adapta4ons to parasi4sm Molecular mimicry by pathogens Mezei, Agnes Meier, Anja Lubosch, Alexander Dinges, Gesa Chelius, Xenia Breu, Mike Bayer, Katharina Molecular interac4ons and signaling mechanisms during erythrocyte invasion by malaria parasites Mechanisms of drug resistance Chemosensory behaviour of parasite Parasite-‐induced behavioural altera4ons of the host: fact or fic4on? Virulence mechanisms of Toxoplasma gondii Ectoparasites: Lice and 4cks Virulence mechanisms of Entamoeba histoly4ca 12.5. 12.5. 12.5. 19.5. 19.5. 19.5. 26.5. 26.5. 26.5. 2.6. 2.6. 2.6. 16.6. 16.6. 16.6. 23.6. 23.6. 23.6. 30.6. 30.6. 30.6. Location: Seminarraum S33, Mondays 17:00-19:00 7 Recommended Literature • Roberts,L. and Janovy, J.: Foundations of Parasitology, 8th ed., McGraw-Hill, 2009 • Bogitsh, B.J. et al.: Human Parasitology, 4th ed., Academic Press 2013 • Lucius, R. and Loos-Frank, B.: Biologie von Parasiten, 2nd ed., Springer, 2008 • Additional Literature on Teaching-website of Genetics Department 8 4 Additional online-Material • Website: Lehrstuhl Genetik->Teaching – http://www.genetik.uni-bayreuth.de/teach/39/SS-14 • • • • Access: username:para password:malaria14 Powerpoints of lectures (as PDF) Additional Literature (papers) Handbook of the Practical 9 Aims of this module • Overview of important parasites causing diseases in humans • Factors leading to the spread of infectious diseases (biological and socio-economic) • Appreciate the diversity of parasites and their lifestyles (e.g. protozoa, worms, ticks) • Insight into molecular mechanisms of pathogenesis • Insight into parasite strategies to survive inside a hostile environment • Pathology and treatment of diseases 10 5 Humans are potential hosts to numerous parasites 11 Parasites of humans 12 6 Infectious Diseases as Major Cause of Mortality World Coronary heart disease Stroke and other cerebrovascular diseases Lower respiratory infections Chronic obstructive pulmonary disease Diarrhoeal diseases HIV/AIDS Tuberculosis Trachea, bronchus, lung cancers Road traffic accidents Prematurity and low birth weight Deaths in millions % of deaths 7.2 5.71 4.18 3.02 2.16 2.04 1.46 1.32 1.27 1.18 12.2 9.7 7.1 5.1 3.7 3.5 2.5 2.3 2.2 2 Source: WHO 2004 13 The global importance of infectious diseases Mortality/100.000 Infectious diseases Noncommunicable (e.g. cancer, cardiovascular)* Injuries 230 573 78 Low income regions 636 757 124 High income regions 380 41 Global *Note 31 that certain cancers and autoimmune diseases are linked to infections Source: WHO World Health Statistics 2012 (data for 2008/9) 14 7 Infectious Diseases as Major Cause of Mortality in Poor Countries Low-income countries Lower respiratory infections Coronary heart disease Diarrhoeal diseases HIV/AIDS Stroke and other cerebrovascular diseases Chronic obstructive pulmonary disease Tuberculosis Neonatal infections Malaria Prematurity and low birth weight Deaths in millions % of deaths 2.94 2.47 1.81 1.51 1.48 0.94 0.91 0.9 0.86 0.84 11.2 9.4 6.9 5.7 5.6 3.6 3.5 3.4 3.3 3.2 Source: WHO 2004 15 A brief history of infectious diseases • Plague • Killed up to 60% of population in the Middle Ages • Several epidemics till the 19th century • Still endemic in Asia (India) • Flu • Smallpox • e.g. “Spanish Flu” 1918, 50 million deaths • During the Middle Ages about 10% of all children died of smallpox • The first infectious disease considered eradicated worldwide due to vaccination campaign • Malaria • HIV/AIDS • Tuberculosis • 1.3 million deaths per year • 37 million deaths since ~1990 • 1.8 million deaths per year, re-emerging • SARS/EHEC/Flu/CJD/BSE/??? • Transmission across species borders • spread of drug resistances 16 8 The global burden of neglected infectious diseases DALYs Infected globally Deaths/year 1 Hookworm infec<on Disease 22.1 million 576 million 65.000 2 Ascaris 10.5 million 807 million 60.000 3 Trichuris 6.4 million 604 million 10.000 4 Lympha<c filariasis 5.8 million 120 million 0 5 Schistosomiasis 4.5 million 207 million 280.000 6 Trachoma 2.3 million 84 million 0 7 Onchocerciasis 0.5 million 37 million 0 52.1 million >1 billion Total Source: WHO 2010 DALYs = Disability Adjusted Life Years: The sum of years of potential life lost due to premature 17 mortality and the years of productive life lost due to disability. Why is it still difficult to control or eliminate Infectious Diseases? • Which factors contribute to the continuing persistence of infectious diseases? 18 9 Growing Problems in Controlling Infectious Diseases • • • • • • • Population growth Breakdown of civil infrastructures Wars Failing health care systems Drug resistance Few new drugs Western societies are not (yet) affected 19 Infectious Diseases are a global problem • • • • • Travel & Migration Military engagements Climate change Emerging or re-emerging diseases Drug resistance 20 10 Global development: Example Drinking water quality 21 Lack of improvements is often, but not always, based on income 22 11 Lack of improvements is often, but not always, based on income 23 Increased use of antibiotics contributes to the emergence of resistances 24 12 Increased use of antibiotics contributes to the emergence of resistances 25 Shifts in the usage of antibiotics are due to new resistance patterns 26 13 Increasing costs of treatment due to increase in resistance 27 Lack of investment into infectious diseases research, control and treatment 28 14 What is a parasite? Well, a parasite is an organism that is studied by parasitologists Greek: parasitos, one who eats at the table of another 29 With very few exceptions, we all interact with other species 30 15 Inter-species interactions Symbiosis • General term to describe close inter-species associations Commensalism • Non-obligatory, unilateral or mutual benefit • Phoresis (Transport commensalism) • Protective commensalisms • Cleaning commensalism Mutualism • Usually obligate, mutual benefit, usually essential Predator/Parasitoid • Death of prey (However: “micropredators don’t usually kill) Parasitism • Unilaterally obligate, unilateral benefit, (damage to host) • A well adapted parasite usually does not kill its host! 31 Protective/Transport commensalism (Phoresis) Hermit crab/anemone Fly/lice • Usually not harmful, but sometimes close to parasitism • Often beneficial to one or both partners 32 • Commensalism (latin: sharing the table, Tischgenosse) 16 Synoecious commensalism (de: Entökie “Einmietung”) • Pea crab (Pinnotheres pisum) lives in the shell of certain mussles • For the crab, this association is essential 33 Cleaning symbiosis cleaner wrasse/Putzerfisch Possible application in biological control of fish farms 34 17 Mutualism (sometimes also described as Symbiosis) Cow Termites 35 Predator/Prey 36 18 Parasitoid • • • • Usually insects (e.g. parasitic wasps) Essential for development of parasitoid Association is highly species-specific Always results in death of infected organism 37 Brood parasitism Reed warbler (Teichrohrsänger) feeding a cuckoo chick 38 19 Parasitism Wuchereria bancrofti Lymphatic filariasis 39 Parasites come in various forms Dracunculus medinensis (Guinea worm) Schistosoma 40 20 Parasites can undergo dramatic changes during their life cycle Adult dog tapeworm cysts of a dog tapeworm after surgery 5 mm 41 What is the definition of a parasite? 1. Distinction between micro- and macroparasites I. Microparasites are pathogenic bacteria and viruses • Usually covered by medical microbiology II. Macroparasites are eukaryotic organisms • Protozoa (e.g. Plasmodium falciparum) • Worms • Trematodes (e.g. Schistosomes) Endoparasites • Cestodes (e.g. pig tapeworm) • Nematodes (e.g. roundworm Ascaris) • Arthropodes (e.g. ticks, lice, midges) Ectoparasites 42 21 A functional definition of parasitism • A parasite lives for an appreciable time of its life in or on another organism • Parasites are absolutely dependent on their hosts - They require at least one host to complete their reproductive life cycle • Parasites benefit from this association at the hosts expense and cause damage to the host (loss of fitness to death) 43 Parasites are of no benefit to their hosts Is this statement really true? • What about infections as a driving force of evolution and socialisation? • Development of the immune system • Close co-evolution between hosts and parasites • Possible transition from parasitism to mutualism/ symbiosis • Emergence of widespread parasitic diseases during colonialism/destruction of traditional settlement patterns • However, no immediate benefit (within an individuals life span) is obvious. 44 22 Sources of Information Books: Roberts & Janovy: Foundations of Parasitology, McGraw-Hill, 8th edition, 2009 Bogitsh, B.J. et al.: Human Parasitology, 4th ed., Academic Press 2013 Lucius & Loos-Frank: Biologie on Parasiten, Springer Verlag, 2. Auflage, 2008 (online version available) Websites: http://www.who.int/en/ http://www.who.int/tdr/ http://www.cdc.gov/ 45 http://www.dpd.cdc.gov/DPDx/default.htm 23