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Risk factors for development of schizophrenia
Dunglová, Eva ; Flegr, Jaroslav (advisor) ; Kodym, Petr (referee)
Schizophrenia is a severe disease. There is a complicity of genetic and environmental factors in schizophrenia onset. Factors with probable influence on development of schizophrenia are rate of urbanization, geographic location, migration, month of birth, maternal nutrition during pregnancy and birth complications, stress during pregnancy, length of lactation period, prenatal and postnatal infection exposure, exposure to a cat during childhood or cannabis abuse. Until now the information on the environmental risk factors of schizophrenia mentioned above concludes in possibility of existence of one factor which would be determinative in schizophrenia onset. Vitamin D deficiency could be this key factor. Lack of vitamin D in prenatal and postnatal period is linked with most of the environmental risk factor for schizophrenia mentioned above, so they could be just the indicators of vitamin D deficiency. Powered by TCPDF (www.tcpdf.org)
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Variability of skin colour: causes and implications
Mašek, Jan ; Černý, Viktor (advisor) ; Hora, Martin (referee)
Melanin acts as a solar radiation filter. Genes are responsible for the amount and the type of the melanin produced, however also an UV radiation is able to induce a melanin synthesis. It appears that the UV radiation has been the determining factor in the human evolution to which the skin colour had to adapt. The original colour of skin was fair and pigmentation has developed after the loss of fur. High levels of UV radiation in equatorial Africa presented a selection pressure for dark pigmentation due to its negative effect on skin. On the other hand, it is important that the skin is bright enough so that a part of the UV radiation could pass through and launch the synthesis of vitamin D. When anatomically modern humans spread out of Africa, a decrease in pigmentation occurred in order to adapt for new levels of the UV radiation in new regions. Nutrition and sexual selection also have an effect on the formation of the skin colour but they have rather secondary importance. The variability of this trait is high between populations but very low within the populations, what testifies to a very intense natural selection. It has also been proven that there is a connection between civilization diseases, such as cancer. Differences in the skin colour have also been and still are important for social...
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The most important dietary sources of lipophilic vitamins
Šafránková, Simona ; Hejtmánková, Alena (advisor) ; Táborský, Jan (referee)
Basic piece of knowledge about nutrition and its need should be integral to every mans general knowledge. One of the vital nutritions ensuring a full-functioning organism are vitamins. Vitamins are essential ingredients, which play an important role in the human body and also in the processes of absorption and the exchange of substances between the external environment and living organism. They were discovered recently during the 20th century. The researches on their effects on the human body are still ongoing.
The vitamins are divided into two basic groups, water soluble vitamins, the so called hydrophilic (vitamins B and C), and fat soluble vitamins, the so called lipophilic (vitamins A, D, E and K).
The vitamin A is important to ensure good vision and recognizing colors. It support the quality and growth of bones, affects the egg and sperm and is needed for proper fetal development.
Vitamin A is found in foods of animal origin, such as dairy products, milk, meat and liver. In the food of plant origin, the vitamin A is replaced with many provitamins, of which most important is the beta carotene. A very rich source of these provitamins are leafy greens such as spinach or cabbage.
The recommended daily intake of vitamin A is 800 microgram, according to the standards of Czech republic. This need depends on the gender and age of each individual. The lack of vitamins A causes photophobia and impaired vision. The excess of vitamin A may be toxic for the organism. The interesting fact is that the beta carotene is not considered to be toxic.
Vitamin A is one of the labile vitamins. It is sensitive to heat, light and oxygen. At a gentle meal preparation and usual diet, the losses are around 20 %.
The vitamin D is consisted of group of several biologically active substances, of which the most important are vitamin D2, ergokalciferol, to be found in foods of plant origin, and vitamin D3, cholekalciferol, to be found in foods of animal origin.
In the human body, vitamin D acts as a hormone, it is formed at one point of the organism, but affects a different part of the body. The vitamin D ensures the intake and absorption of calcium and phosphorus and maintain their balance. It supports the immune system and may help in the psoriasis treatment.
The recommended daily intake of vitamin D is about 2,5 to 10 microgram. Pregnant and lactating women have a greater need for it, as well as infants and children. The lack of vitamin D disturbs the homeostasis of calcium and phosphate metabolism. The excess of vitamin D causes hypercalcaemia.
The most important foods source of vitamin D are liver, oil from fish liver, oil sea fish, fortified margarine and milk.
Vitamin D is sensitive to oxygen and light, its activity is not significantly affected by food storage or preparation.
Vitamin E is a major antioxidant. It is important to maintain the healthy cell wall and skin, muscles, nerves, erythrocytes, heart, and it is also responsible for the proper function of blood circulation.
The recommended daily intake of vitamin E is 8 to 20 mg. Its need is increased during exposure to sunlight and harmful influences, during increased physical exertion and when receiving large amounts of unsaturated fatty acids. The lack of vitamin E almost does not occur in healthy people, since it is present in nearly all basic kind of foods. The hypervitaminosis of vitamin E occurs only rarely, because there is no risk of overdose when receiving a normal diet.
The most important foods source of vitamin E are vegetal oils (such as sunflower and rapeseed), nuts, corn, pea, corn products, dark green leaf vegetables, eggs, liver and viscera.
Vitamin E is considered the most stable lipophilic vitamin. There is only a minimal loss of tocopherol during food processing, these losses are approximately 10 %.
The vitamin K supports blood clotting in the human body and, along with the vitamin D, is involved in the constant bone development and remodeling.
Both foods of plant and animal origin are sources of vitamin K, such as meat, liver, milk, vegetables and fruit. The recommended daily intake of vitamin K is around 0,01 to 0,14 mg. The infants and children up to three years have lower need of vitamin K intake. The most common cause of vitamin K hypovitaminosis is disruption of intestinal microflora caused by various drugs, e.g. antibiotics. Too high doses of vitamin K can accumulate in the body and lead to the breakdown of erythrocytes, damage the liver and cause jaundice in children.
There is not much information known about the stability of vitamin K yet. It has been found that vitamin K decomposes rapidly in the light, however its losses during food processing are minimal.
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Retence fosforu krmiva v chovu ryb
Malý, Ondřej
The aim of this study was observed the digestibility of diet phosphorus in fishfeed for carp (Cyprinus carpio). Observation of phosphorus digestibility is important factor for fishery in terms of environmental pollution and reduction of feed costs. Sixty carps were divided into three groups. Control diet and two experimental diets were used in this study. The basic of each diet was granulated mixture KP1. Digestibility of phosphorus in experimental diets was supported by the addition of microbial phytase OptiPhos5000 CT. Content of phytase was 500 FTU in first experimental diet (F500) and 1000 FTU in second experimental diet (F1000). Indicator method was used for determination of phosphorus digestibility. Fiber was used as indicator. Excreta of carps were collected for twelve days. Phosphorus digestibility of control group was 63.9%. There was found lower phosphorus digestibility (62.6%) in the group fed diet with phytase 500 FTU. In the group fed diet with the largest content of phytase (1000 FTU) was observed 62.2% of phosphorus digestibility. According to the obtained results it can be concluded that the addition of phytase did not affect the digestibility of phosphorus. The reason for these results could be improperly chosen of method.
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Risk factors for osteoporosis - knowledge and behavior of adolescent girls
KVASNÍKOVÁ, Martina
The thesis deals with the theme of risk factors for osteoporosis, knowledge and behavior of adolescent girls. The theoretical part of the thesis is divided into four chapters. The first chapter deals with the anatomy and physiology of bone. The second chapter discusses general information about osteoporosis. The third chapter summarizesthe prevention of osteoporosis and in the fourth chapter describes the treatment of osteoporosis. In the practical part of thesis was used method quantitative research. The target group consisted of 100 adolescent girls in the age range of 15-17 years of grammar school and vocational school in the České Budějovice. The girls were interviewed using a questionnaire, which consisted of questions related to osteoporosis. In thesis were determined two main objectives. The first of them was to map the knowledge of adolescent girls in the prevention of osteoporosis. The second objective is concerned with mapping the behavior of adolescent girls in the prevention of osteoporosis. The first research question dealt with by what kind of knowledge adolescent girls in the prevention of osteoporosis. The second research question was focused on the behavior of adolescent girls in the prevention of osteoporosis. According to the questionnaires can be concluded that the majority of respondents are not sufficiently informed about osteoporosis, but I find girls that basic information about the disease they have. Questionnaires filled in by teenage girls from the first and second years of grammer school and vocational school, therefore, the results are compared with one another. The survey shows that respondents from vocational school awareness of osteoporosis do not. Girls from grammer school have heard about this disease, but they can´t define it. The reason for this ignorance is that girls (from grammer school and from vocational school) have never been informed about osteoporosis. This fact mention the majority of the respondent girls. In most cases in the families of the respondents there is not osteoporosis or the girls do not know. On the following questions in the questioannarire girl (from both schools) have marked mostly option "not know". It were a questions whether sex hormones protects to some extent against osteoporosis. Furthermore, for which persons osteoporosis frequently occurs, whether the osteoporosis relate with calcium and vitamin D, or not. Schoolgirl from grammer school and vocational school mostly said that they consume milk and milk products several times a day or once a day. Of the 100 respondents sonly 18 girls said that do not drink alcohol. A total of 55 female students do not smoke and 23 female students smoke. The number of girl who smoke from vocational school is more than number of girls from grammer school. Schoolgirls of grammer school correctly think that physical activity can affect osteoporosis, the respondents of vocational school hold a different opinion. All of the girls regularly do sports, except for the two girls who do not purposefully movement. Based on the information from the questionnaire it would be appropriate that the teenager girls should be more informed about osteoporosis. There are several variations, such as educational material prepared for teenage girls or classes in school or self studying. Very important is the prevention of osteoporosis. The important role have a adequate nutrition and physical activity. Therefore, it is necessary to increase the knowledge of adolescent girls about the disease, so they can avoid.
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Calcium in foods and its importance for nutrition
POKORNÁ, Veronika
This bachelor's thesis deals with the calcium in food and its importance for the nutrition of students at second grade of primary school. The theoretical part discusses the general characteristics of calcium, especially the chemical, physical and biological significance of chemical compounds, the occurrence of calcium in water and nature. It is focused on the calcium content in foods of animal and vegetable origin. Finally, in the theoretical part, is outlined the importance of calcium for the human body, especially the intake, absorption, excretion and consequences of its insufficient income, for example hypocalcemia, osteoporosis and osteomalacia. Practical work is focused on findings to estimate the knowledge of students aged 12 to 15 years about calcium and consequently its consumption, occurrence in foods and the importance of nutrition, using a questionnaire. The results are evaluated and graphically presented.
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Human nutrition like part of prevention in osteoporosis and osteomalacia
BRABCOVÁ, Markéta
The purpose of this baccalaureate work is to study deseases related to osteoporosis and osteomalacia. It describes the composition of the bones, historical occurrence of osteoporosis, the characteristics of the osteoporosis and osteomalacia, as well as the differences between these osseous diseases. Furthermore, the present work focuses on the prevention of osteoporosis from the nutrition point of view. It analyses the influence of mineral substances, vitamins and hormons on the formation of bones. Osteoporosis is an old disease. Women suffering from osteoporosis can be seen already on some Chinese and Greek paintings. Premature osteoporosis has been noticed also in skeletal residues of young women steming from the 3rd - 5th centuries A.D. In such young women, the osteoporosis was due to consumption of bread containing a higher portion of phytate which bonds calcium. Within the whole group of osseous metabolic osteopathias, the osteomalacia is the least frequent one. It can be found also in developing countries like India and Pakistan, but also in Muslim minorities living in the United Kingdom. It originates in the shortage of vitamin D. The purpose of this work was to find out to which extent the human nutrition influences bone diseases. A bone is never a finished product, it is subject to a continuous process of creation and destruction. Osteoporosis is a result . In aging individuals, the destruction of bones predominates over the creation of new ones, the total osseous substance decreases as such and there is an excessive decrease in all bone components - minerals, especially in calcium. This is why calcium reserves in bones are so important. The level of sexual hormons as well can cause an accelerated decrease in osseous substance. We refer here to the so-called menopausal osteoporosis which occurs in women. In men, it occurs at a later age and has a milder course. Osteomalacia is originated by a malfunction of the mineralisation of bones. There is a sufficient quantity of osseous substance, however, what is missing are minerals. A good mineralisation of bones requires enough vitamin D, calcium, phosphorus, magnesium and trace elements boron and fluorine. Osteoporosis and osteomalacia are, in the last years, an increasingly serious problem in the developed countries, as a consequence of the increasing life expectancy. The treatment of osteoporosis and osteomalacia is very expensive, and this is why so much emphasis is placed in their prevention. Prevention measures should be commenced as soon as possible, because lack of calcium in the infant food and in the nutrition of young people causes health problems and is the inception stage of osteoporosis. The most important preventive measure is a sufficient supply of calcium and vitamin D. Other measures are physical training and exercises, staying in the sun, a sufficient supply of minerals - magnesium, phosphorus, fluorine and vitamins, especially vitamins C, K and B12 from the daily food. A negative effect on the bones is caused by excessive consumption of proteins and caffeine, which leads to calciuria. A nutrition rich in fruits and vegetables increases the alkalinity of the environment, which reduces the calciuria.
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