Sources: cereals zebeta 10mg discount hypertension treatment algorithm, legumes cheap zebeta 10 mg online pulse pressure equation, raisins generic 10 mg zebeta free shipping blood pressure chart by age and gender, nuts etc Functions: • Cofactor of enzymes like cytochrome oxidase cheap 10mg zebeta fast delivery hypertension in young adults, dopamine decarboxylase, tyrosinase, Cyt. C oxidase and superoxide dismutase and monoamine oxidases are dependant on copper. Tyrosyl oxidase is important for collagen metabolism ++ +++ • Ceruloplasmin (serum ferroxidase) catalyses Fe to Fe , a pre requisite for the incorporation of iron into transferrin. Menke’s disease or Kinky hair syndrome: It is fatal sex linked recessive disorder in which there is cerebral and cerebellar degeneration, connective tissue abnormalities and kinky hair. Patient has normal absorption of iron but transport across the serosal aspect of mucosal membrane is defective. Patients are treated with Pencillamine, which binds to tissue copper and mobilizes it. Sources: Widely distributed in vegetables, chlorophyll, cereals, beans, potatoes, cheese and animal tissues. Fluorine It is solely derived from water, tea, and fish Daily intake should not be more than 3mg. Small quantities of it promotes bone development, increases retention of calcium and phosphate, prevent osteoporosis • High level of fluoride in bone causes abnormal rise in calcium deposition, increases bone density Flurosis is due to toxicity of fluoride. Excess can be due to high dietary intake, contaminated water or inhalation of fluorine. Iodine Sources: Vegetables, fruits obtained from sea shore, sea fish are rich in iodine. It is absorbed from small intestines and transported as protein complex in plasma. See the details of iodine metabolism, thyroid hormone synthesis from the chapter on hormones. Zinc Sources are liver, milk, fish, dairy products, cereals, legumes, pulses, oil seeds, yeast and spinach etc. Absorption of Zinc from the intestine appear to be controlled in a manner similar to Iron. It is transported bound to a protein (α2-macroglobulin and transferrin) It is excreted in urine and feces. The body does not store Zinc to any appreciable extent in any organ, urinary excretion is fairly constant at 10 μmol/day. Retenene reductase (zinc enzyme) participates in the regeneration of rhodopsin (visual cycle). Deficiency of Zinc: Patients requiring total parentral nutration, pregnancy, lactation, old age and alcoholics have been reported as being associated with increased incidence of Zinc deficiency. Deficiency of selenium: • Liver cirrhosis • Pancreatic degeneration • Myopathy, infertility • Failure of growth Toxicity: - Selenium toxicity is called Selenosis - Toxic dose is 900micro gram/day - It is present in metal polishes and anti-rust compounds 191 - The Toxicity symptoms are Hair loss,failing of nails, diarrhea,weight loss and gaslicky odour in breath(due to the presence of dimethyl selenide in expired air). Introduction Hormones are responsible for monitoring changes in the internal and external environment. They direct the body to make necessary adaptations to these environmental changes. Tissue production (paracrine) of hormones is also possible Hormones and Central nervous system interact to shape up development, physiology, behaviour and cognition. The actions and interactions of the endocrine and nervous system control the neurological activities as well as endocrine functions. A messenger secreted by neurons is neurotransmitter while the secretion of endocrine is called hormone. Cellular functions are regulated by hormones, neurotransmitters and growth factors through their interaction with the receptors, located at the cell surface. Part of chapter discusses receptors, signal transduction and second messenger pathways. Both hyper and hypo-function of the endocrine glands produce distinct clinical symptoms. The basic information provides a solid foundation from which to view the existing and future developments in the rapidly moving discipline. Major endocrine glands are pituitary, hypothalamus, thyroid; adrenals, pancreas, ovaries and testes. Hormones can be classified based on their structure, mechanism of action, based on their site of production etc. Sometimes the concentration of the hormone is less, which stimulates the production of hormone by a process of feedback stimulation. Some protein hormones are synthesized as precursors, which are converted to active form by removal of certain peptide sequences. It is synthesized as a glycoprotein precursor called thyroglobulin, which has 115 amino acids. Other hormones like glucocorticoids/ minerolacorticoids from Adrenal gland are synthesized and secreted in their final active form. Pro-hormones: Some hormones are synthesized as biologically inactive or less active molecules called pro-hormones. Storage Hormones are stored in secretory granules within the cytoplasm of endocrine cells. Release: • When the target cells require free hormones, they are released immediately. It involves fusion of granules and cellular membrane, followed by secretion in to blood stream. Free Hormone concentration correlates best with the clinical status of either excess or deficit hormone. Hormone action and Signal Transduction Based on their mechanism of action, hormones are divided into two groups, steroid and peptide/protein hormones. Mechanism of action of steroid hormones • The group consists of sterol derived hormones which diffuse through cell membrane of target cells. Mechanism of action of Protein hormones: • The group comprises the peptide/protein hormones. Lipophilic hormones like steroids, thyroxine are recognized by intracellular receptors, eg. Receptor binding to hormone involves electrostatic and hydrophobic interactions, and is usually reversible process. Prolonged exposure to high concentration of hormone leads to decreased receptors, called as desentitization. Down regulation: There is internal distribution of receptors such that few receptors are available on the cell surface. Removal of receptor to the interior or cycling of membrane components alters the responsiveness to the hormone. In another type of down regulation, H-R complex, after reaching nucleus controls the synthesis of receptor molecule. Some times Covalent modification of receptors by phosphorylation decreases binding to hormone, which diminishes signal transduction. Up regulation: Some hormones like prolactin up regulate,(increase) their own receptors which ultimately increases the biological response and sensitivity in target tissues. Receptors and diseases: Abnormality in the receptors cause the following diseases. This molecule mediates phosphorylation of intracellular proteins, by activating protein kinase A. Protein kinase A is a tetramer having two regulatory units and two catalytic units (R2C2). The inhibitory system consists of different receptors (Ri), and inhibition regulatory complex (Gi). Bacterial Toxins: Vibrio cholerae produce entero toxin which binds to ganglioside (Gm) from the intestinal mucosa. Intracellular Ca is increased by a) Entry of Ca from extra cellular region when stimulated.
Gastrointestinal helminth parasites of the black rat (Rattus rattus) in Abeokuta order zebeta 5mg without prescription low pressure pulse jet bag filter, southwest Nigeria buy discount zebeta 5mg on-line blood pressure medication cialis. Intestinal perforation due to Macracanthorhynchus hirudinaceus infection in Thailand zebeta 5 mg hypertension 16070. Etiology: The agents of this disease are the metastrongylid nematodes Angiostrongylus (Morerastrongylus) costaricensis order 10mg zebeta heart attack 2013, A. The first of these nematodes was recognized as a parasite of man in Taiwan in 1944; the second was described in Costa Rica in 1971, although the human disease had been known since 1952; the third was identified in Japan in 1990 and was subsequently diagnosed in aborigines in Malaysia. The first species is responsible for abdominal angiostrongyliasis; the second for eosinophilic meningitis or meningoencephalitis; and the third, A. Some 12 other rat species have been found to be infected; coatis (Nasua arica), monkeys (Saguinus mystax), and dogs can be exper- imentally infected. The female lays eggs in those arteries; the eggs are then carried by the bloodstream and form emboli in the arterioles and capillaries of the intestinal wall. The eggs mature and form a first-stage larva which hatches, penetrates the intestinal wall to the lumen, and is carried with the fecal matter to the exterior, where it begins to appear around the twenty-fourth day of the prepatent period of the infec- tion. In order to continue their development, the first-stage larvae have to actively penetrate the foot of a slug of the family Veronicellidae (particularly Vaginulus ple- beius) or be ingested by it. In Brazil, four species of Veronicellidae slug were found to be infected: Phyllocaulis variegatus, Bradybaena similaris, Belocaulus angustipes, and Phyllocaulis soleiformis (Rambo et al. In the slug, the lar- vae mature and change successively into second- and third-stage larvae in approxi- mately 18 days. The third-stage larva, which is infective for the definitive host, is eliminated with the slug’s mucous or slime, and contaminates the soil and plants around it (Mojon, 1994). When the definitive host ingests the infective larva in the free state or inside the mollusk, the larva migrates to the ileocecal region, penetrates the intestinal wall, and invades the lymphatic vessels. In this location the larvae undergo two molts before migrating to their final habitat: the mesenteric arteries of the cecal region. The parasite can complete the life cycle in man, an accidental host, reaching sexual maturity and producing eggs, but the eggs usually degenerate, caus- ing a granulomatous reaction in the intestinal wall of the host. The intermediate hosts are various species of land, amphibian, or aquatic gastropods, e. The definitive hosts can become infected by ingesting the infective third-stage larvae, either with infected mollusks or with plants or water contaminated with the larvae that abandon the mollusk. In addition, infection can occur as a result of consuming transfer hosts (paratenic hosts), such as crustaceans, fish, amphibians, and reptiles, which in turn have eaten infected mol- lusks or free larvae. When a definitive host ingests an infected mollusk or infective larvae, the larvae penetrate the intestine and are carried by the bloodstream to the brain, where they undergo two additional changes to become juvenile parasites 2 mm long. From the cerebral parenchyma, they migrate to the surface of the organ, where they remain for a time in the subarachnoid space and later migrate to the pul- monary arteries, where they reach sexual maturity and begin oviposition. The eggs hatch in the pulmonary arterioles or their branches, releasing the first-stage larva, which penetrates the pulmonary alveoli and migrates through the airways to the pharynx; there it is swallowed and is eliminated with the feces starting six weeks after infection. Snails or slugs, which are the intermediate hosts, become infected when they ingest the feces of infected rodents. The third-stage infective larva forms in the mollusk in 17 or 18 days and can remain there for some time or be expelled and contaminate the envi- ronment. A large number of paratenic or transport hosts, such as crustaceans, fish, amphibians, or reptiles, may become infected with these larvae and, in turn, infect rats or human beings. The adult parasite has been found in rats, and its larva infects the snail Biomphalaria glabrata, although not as easily as it infects A. It has been iden- tified in children in Costa Rica since 1952, and more than 130 human cases had been diagnosed when Morera and Cespedes described the parasite in 1971. Morera (1991) indicated that about 300 cases a year were diagnosed in Costa Rica alone. In 1992, two cases were discovered in children on the French island of Guadeloupe in the Caribbean (Juminer et al. The first known epidemic occurred in 1994–1995 in Guatemala and affected 22 persons (Kramer et al. With respect to the animal definitive hosts, 15% of Rattus norvegicus and 6% of R. In Panama, the adult parasite was found in five species of rodents belonging to three different families. It is highly probable that the parasitosis is much more wide- spread than is currently recognized. In 1992, 27 cases had been reported in Japan, the majority in the prefecture of Okinawa. It is believed that the parasite was introduced to the island some years ago by rats from a ship from Asia. Since 1950, cases have been identified in Indonesia (island of Sumatra), Philippines, Taiwan, and even Tahiti. It subsequently appeared in Australia, mainland China, India, and Japan (Okinawa). The Disease in Man: The clinical manifestations of abdominal angiostrongylia- sis caused by A. Leukocytosis is characteristic (20,000 to 50,000 per mm3), with marked eosinophilia (11% to 82%). Lesions are located primarily in the ileocecal region, the ascending colon, appendix, and regional ganglia. Granulomatous inflammation of the intestinal wall can cause partial or complete obstruction. Out of 116 children with intestinal eosinophilic granulomas studied from 1966 to 1975 in the National Children’s Hospital in Costa Rica, 90 had surgery (appendectomy, ileocolonic resection, and hemicolectomy). Ectopic localizations may occur, such as those found in the livers of Costa Rican patients with visceral larva migrans-like syndrome (Morera et al. In Taiwan, the disease occurs mainly in children, but in other endemic areas it occurs in adults. A study of 82 children found that the incubation period was 13 days, shorter than the average of 16. The symptoma- tology of meningitis and eosinophilic meningoencephalitis was studied in 1968 and 1969 in 125 patients from southern Taiwan. Most patients had a mild or moderate symptomatology, and only a few suffered serious manifestations; four of the patients died and another three had permanent sequelae. In 78% of the patients, the disease had a sudden onset, with intense headache, vomiting, and moderate intermittent fever. More than 50% of the patients experienced coughing, anorexia, malaise, constipation, and somnolence, and less than half had stiffness in the neck. Pleocytosis in the cerebrospinal fluid was particularly pronounced in the second and third weeks of the disease. The percent- age of eosinophils was generally high and was directly related to the number of leukocytes in the cerebrospinal fluid. While there are no effective anthelminthic and the headaches and weakness can last a few weeks, as a general rule the patient recovers without sequelae. The reason for the different clinical pictures is not known, but the severe cases may be due to the higher number of parasites present (intensity of infection). Eosinophilic meningitis usually occurs after the ingestion of paratenic hosts or contaminated vegetables containing few larvae; the most serious forms of the disease are due to direct consumption of highly infected intermediate hosts (Kliks et al.
In contrast buy zebeta 5mg low price blood pressure lowering, important in the dissemination of genes in unlike many of the bacterial species men- natural populations (Stevens et al purchase 5mg zebeta with amex blood pressure gauge. The role in transduction mechanism of genetic exchange observed in and bacteriophages in horizontal transfer is S generic 10 mg zebeta mastercard arteria urethralis. The majority of Leonard and co-workers when they identiﬁed studies into streptococcal transduction were ﬁve phages discount zebeta 5 mg on-line blood pressure exercise program, two temperate and three lytic, carried out before the advent of many of the that were able to transduce streptomycin current techniques in molecular biology, and resistance (Leonard et al. The highest so the time may have come to re-examine this frequency of transduction was observed for phenomenon. A beter understanding of lytic phage A25 (1 10–6 plaque-forming streptococcal transduction may prove key to units). 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Diversity of stx2 converting bacteriophages (2006) Predominance of clones carrying induced from Shiga-toxin-producing Escherichia Panton–Valentine leukocidin genes among coli strains isolated from cattle. Journal of Clinical Microbiology (2004b) Free Shiga toxin bacteriophages 44, 4515–4527. Journal of Clinical Microbiology 46, Phage conversion of Panton–Valentine 3246–3258. Nature (2007) A generalized transducing phage for the Reviews Microbiology 8, 541–551. Shiga-like toxin-converting phages from (2003a) Superantigens and streptococcal toxic Escherichia coli strains that cause hemorrhagic shock syndrome. Infection and Immunity Sequence analysis of Escherichia coli O157:H7 70, 1896–1908. Applied and Zentralblatt für Bakteriologie A 247, 95–100 (in Environmental Microbiology 73, 8032–8040. Journal of General Microbiology 39, innate immune modulators staphylococcal 321–333. Journal of Experimental Medicine Bioscience, Biotechnology and Biochemistry 137, 1338–1353. Hendrickson 5 The Lion and the Mouse: How Bacteriophages Create, Liberate and Decimate Bacterial Pathogens Heather Hendrickson1 1New Zealand Institute for Advanced Study, Massey University ‘…I had my eyes opened by that microscope, to the fact that there is a world of tiny creatures that you can’t see with the naked eye. Like the So interdependent are these organisms that ratchet in the handyman’s tool box, mutation deﬁning which is the proverbial lion of the can be thought of as only permiting change jungle and which the unassuming mouse can in a single direction, that is, away from the be a challenge. On in bacteria means there is no opportunity to evolutionary timescales, however, phages reshuﬄe combinations of genes that sexually also can convert bacteria from pussy cats into reproducing organisms have, which produce the human predators we call pathogens. A are the accidental architects of the genetic continual accumulation of deleterious combinations that we observe in the bacterial mutations over time is predicted to eventually world. This has profound lineages afer a mere 1700 generations consequences for these organisms and their (Andersson and Hughes, 1996). Thus phages and of fresh insight into the evolutionary processes bacteria are engaged day to day in a undergone by bacteria (Fleischmann et al. In population growth amounts of genomic content in some fraction experiments where bacterial genetic diversity of extant lineages would be novel and notable, would normally emerge as a result of niche there are recent suggestions that an average of specialization and trade-oﬀs, the eﬀect of 81% of bacterial genes might be acquired adding predatory phages is to decrease horizontally (Zhaxybayeva et al. Two major have been proposed as the standard for advantages in using parametric methods are phylogenetic comparison across the three that they are computationally simple and that domains of life because these molecules are multiple genomes for comparison are not present in all branches of life and are required for transferred genes to be identiﬁed. Even this overlapping but diﬀerent sets of genes for paragon of molecular metrics, however, has the same genome. This is due, in part, to been horizontally transferred in some cases the confounding similarity in mutational (Gogarten et al. Homologous genes from process termed amelioration (Lawrence and diﬀerent organisms can therefore be used to Ochman, 1997). Developmental stages in bacterial align with the inferred organismal tree then a growth, such as sporulation in Bacillus subtilis, transfer event can be inferred (Snel et al. Hendrickson organismal tree to use as the benchmark for recipient genome, and this acquisition takes such comparisons? Multiple methods are place through three processes: transformation, being developed to determine the phylo- conjugation and transduction (Fig. This hypothesis Conjugation Transformation received support recently through direct testing using a set of ubiquitously conserved gene sequences, which suggested a high-level Transduction tree of universal relatedness (Theobald, 2010). How Bacteriophages Create, Liberate and Decimate Bacterial Pathogens 65 it can then be recombined into the recipient selective constraints in order to be maintained genome by repair-like recombination pro- for long periods of time. As such, the that can be as short as 1 kb and can range up following is far from an exhaustive discussion to many hundreds of kb. Upon more detailed but gives a breadth of mechanisms that analysis, many of these gaps can be atributed constrain gene transfer. Integrated phage transmitance of genetic material between genomes can carry genetic elements that donor and recipient cells. This is mediated by contribute both to the pathogenicity of the multiple processes, all of which will have strain and to their own retention (Brüssow et natural host-range limitations to one degree al. If organisms that are the recipient bacterial chromosome or other most closely related are those that are cytoplasmic replicon such as a native plasmid. The mismatch repair in higher organisms contributes directly to system, for example, acts to correct mutations, the species cohesiveness (and, indeed, deﬁnes including small insertions and deletions. This will be less likely to to mismatch repair anti-recombination interfere with segregation afer integration. Transfer that involves re- An additional, sequence-based dis- combination into plasmids will also avoid the crimination mechanism has been recognized constraints of integrating into a structured in the clustered, regularly interspaced, short genome. By contrast, the acquired for destruction and have been shown to functions of the inherited genes have the interfere with lateral gene transfer (Marraﬃni potential to increase the ﬁtness of the and Sontheimer, 2008). Interruptions of important genes or unlikely to be anything more than neutral or regulatory regions, for example, tend to be may be deleterious to the ﬁtness of the detrimental to ﬁtness. Observations of becoming organelles such as mitochondria recently acquired genes may reﬂect neutral or and chloroplasts (Gray and Doolitle, 1982; even disadvantageous acquisitions in the Moran, 1996; Lang et al. It should be noted, however, that a been maintained up to that point by genetic recent study suggests that rare co-infection drif. Thus, a genome sequence should be events can support genetic exchange in some considered to be a snapshot of a single cases between such obligately intracellular bacterium at some point on its evolutionary bacteria (Kent et al. These ‘core’ extant organisms are subject to both genes, however, have been observed to be speculation and ﬁerce debate.
By contrast cheap 5 mg zebeta visa prehypertension at 24, the increase in more-developed nations buy zebeta 5 mg line blood pressure medication prices, largely attributable to an 29 expansion of the population of older people at risk zebeta 5mg online blood pressure emergency, will range between 30% and 60 % buy 10mg zebeta mastercard prehypertension icd 9 code. International Cardiovascular Disease Statistics 5 • In England, the death rates for stroke for people under 65 fell by 23 percent in the last 10 years. Recently, rates have declined at a slower rate, particularly in the younger age groups. The European countries were Germany, 17 Finland, Sweden, England, Spain and Italy. In those older than age 3 60, as many as one-half in some populations are hypertensive. In Mexico (1997) female deaths from hypertension surpassed those for males, starting at age 35. The prevalence of hypertension in Latin America and the Caribbean has been estimated at between 8 and 30 16 percent. Some 250,000 deaths could be prevented each year through effective case management. Hypertension-related 19 stroke rate is high in Africa, and victims are relatively young. In general, awareness of hypertensiona nd use of medication increased with income. In Asia, a steep increase in stroke mortality has accompanied a rapid rise in the prevalence of hypertension. Rheumatic Fever/Rheumatic Heart Disease International Cardiovascular Disease Statistics 6 • In developing countries, rheumatic fever is the most frequent cause of heart disease in the 5-13-year-old group, causing 25-40 percent of all cardiovascular diseases and 33-50 20 percent of all hospital admissions. A few studies conducted in developing countries report incidence rates ranging from 1. These direct costs divert the scarce family and 4 societal resources to medical care. Developing countries show an 5 increasing prevalence, with higher rates in urban than in rural areas. International Cardiovascular Disease Statistics 7 • Economic transition, urbanization, industrialization and globalization bring about lifestyle changes that promote heart disease. Urban dwellers may believe that a diet high in energy and fat, similar to that of Western affluent countries, is a symbol of their new status. The global availability of cheap vegetable oils and fats has led to greatly increased fat consumption among low-income countries. Despite that fact, worldwide trends show more young smokers, especially young women. Mortality from any cardiovascular disease was around 60 percent higher in smokers ( and 85 percent higher in heavy smokers) than in non-smokers. Many of International Cardiovascular Disease Statistics 8 these children started smoking before age 10. An overwhelming majority want to quit but are 1 unable to do so because of nicotine addiction. Tobacco use is responsible for about 5 1 million deaths a year, mostly in poor countries and poor populations. This is especially evident in populations whose diets are high in saturated fat with subsequent high blood cholesterol and high blood 5 pressure. International Cardiovascular Disease Statistics 9 • High blood cholesterol is estimated to cause about 4. Physical Inactivity • From 60 to 85 percent of the world population from both developed and developing 8 countries are not physically active enough to gain health benefits. In Europe only 3 countries offer at least 2 hours per week of physical education courses. In the United States in the last 30 years the prevalence of overweight children ages 5-14 has increased from 15 to 32 percent. Obesity kills about 220,000 men and women annually in the United States and Canada and about 320,000 men and women in 20 countries of Western 13 Europe. Projections indicate that by 2025, 37% of men and 40% of women 30 will be overweight, compared to 8% and 12% in 1995. The number of adults with diabetes in 28 the world is estimated to rise from 135 million in 1995 to 300 million in 2025. The rate of increase ranges from 2 to 6 percent in most of the countries and up to 8 percent in men in Barbedos. The age distribution shows that its greatest effect is on 16 women starting at age 40. Nutrition • Availability of calories per capita from the mid-1960s to 1997-99 increased globally by about 450 kcal/capita/day and in developing countries by 600 kcal/capita/day. Per capita supply of calories remained almost stagnant in sub- Saharan Africa and showed a decreasing trend in the transition countries. In contrast, the per capita supply of energy rose dramatically in East Asia (mainly in China) and in the Near 7 East/North Africa. The highest available vegetable supply is in Asia and the lowest in South America and Africa. Only a small and negligible minority of the world’s population consumes at present the generally recommended high average intakes of fruits and vegetables. The availability of 7 fruit generally decreased between 1990 and 1998 in most regions of the world. About 13 percent of men and 15 percent of women consume the recommended five or more portions of fruit and vegetables daily. Among British children ages 2-15 the average food energy derived from fat is 35 percent for 11 boys and 36 percent for girls. Links to Web Sources Note: These links are provided as a helpful reference tool for finding information. The data are not complete and may not be consistent as to the type of data and years available. Please note that more complete data from more developed nations (like the United States) can be found on government health sites for those countries. Institute for International Health – Global Burden of Disease International Cardiovascular Disease Statistics 13 http://www. It includes systematic tabulations of health spending by source, use and function. International Cardiovascular Disease Statistics 14 World Federation of Public Health Associations http://www. Hypertension prevalence and blood pressure levels in 6 European countries, Canada, and the United States. Overweight is an independent risk factor for cardiovascular disease in Chinese populations. The Challenge of Cardiovascular Disease in Developing Economies,” 2004 Columbia University, New York. By following a series of systematic steps, an unbiased, organized assessment of the problem can be made, and the likelihood of understanding a disease outbreak is increased. Introduction ing these disease patterns and relating them to the While individual sick or injured horses can be chal- patterns of potential risk factors that allows identiﬁ- lenging cases, problems affecting a large number of cation of measures to prevent new cases of disease animals at the same time can be unsettling and even and future outbreaks. Typically, it is cases of Different combinations of infectious or toxic agents, respiratory disease, diarrhea, or abortion that make individual and herd immunity, population age and a practitioner wonder if they might be seeing the movement, nutrition and environmental factors may contribute to an outbreak of disease. It is possible, is possible to identify the cause or causes of an however, to encounter cases of neurologic disease, outbreak simply using keen observation and intu- sudden death, even colic or lameness that may be ition gained through experience. Unfortunately, this part of a larger problem affecting a number of approach can be biased easily by an individual’s animals.