Enforce of pfysical, chemical and biological factors in pathogenesis of diseases

Enforce of pfysical, chemical and Enforce of pfysical, chemical and biological factors in pathogenesis of biological factors in pathogenesis of

diseasesdiseases

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Mechanical influencesMechanical influences

Contusion, oppressionContusion, oppression Tissue disruption, infractionTissue disruption, infraction Bone fracturesBone fractures Distorsion or luxation of jointsDistorsion or luxation of joints Vessel disturbancesVessel disturbances Traumatic shockTraumatic shock

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Traumatic shockTraumatic shock

Ethiogenesis: pain and blood lossEthiogenesis: pain and blood loss Overload reactinOverload reactin Inflammatory reactionInflammatory reaction Vascular reaction – tissue hypoxiaVascular reaction – tissue hypoxia Metabolic acidosisMetabolic acidosis

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Exposure to traumaExposure to trauma

Fat embolismFat embolism Air embolismAir embolism Crush syndromeCrush syndrome

develops after trauma followeddevelops after trauma followed

by contusio and break up by contusio and break up

(decomposition) of sceletal muscles (decomposition) of sceletal muscles

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Body core temperatureBody core temperature

Regulation of body core temperatureRegulation of body core temperature

Hypothalamic thermoregulatory centreHypothalamic thermoregulatory centre Vessel reaction (vasoconstriction and vasodilatation)Vessel reaction (vasoconstriction and vasodilatation)

Creation (generation) of warmth (heat)Creation (generation) of warmth (heat)

Metabolism Metabolism production under influence of some hormonsproduction under influence of some hormons catecholamines, thyroxin, tetraiodthyronin catecholamines, thyroxin, tetraiodthyronin

Contraction of sceletal musclesContraction of sceletal muscles shivering thermogenesisshivering thermogenesis

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Acquirement and loss of warmthAcquirement and loss of warmth

Emission - Emission - heat radation heat radation Conduction - Conduction - contact with warm or cold substancescontact with warm or cold substances Convection - Convection - dependent on air flow (ev. water flow)dependent on air flow (ev. water flow) EvaporationEvaporation

Significantelly influenced by relative athmospheric humiditySignificantelly influenced by relative athmospheric humidity

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Effect of (chilli) coldEffect of (chilli) cold

Global (overall) cold effectGlobal (overall) cold effect

a)a) Sympathicus tone:Sympathicus tone: Vasoconstriction in skinVasoconstriction in skin

b)b) Creation of warmthCreation of warmth Voluntary muscle activityVoluntary muscle activity Muscle shiveringMuscle shivering

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HypothermiaHypothermia

Disability of vasoconstriction and muscle toneDisability of vasoconstriction and muscle tone to keep body core temperature:to keep body core temperature: Slowdown heart frequencySlowdown heart frequency Disturbance of cardiac contractilityDisturbance of cardiac contractility Consciousness disturbances:Consciousness disturbances: Unconsciousness in decrease Unconsciousness in decrease of body core temperature below 32of body core temperature below 32OOCC Decrease of metabolic rate Decrease of metabolic rate among 34 – 27among 34 – 27OOC C

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HypothermiaHypothermia

Body core temperature among 34Body core temperature among 34OOC – 27C – 27OOC C Decrease in metabolic rateDecrease in metabolic rate Decrease in muscle toneDecrease in muscle tone VasodilatationVasodilatation Death in temperature decrease to about 24Death in temperature decrease to about 24OO C C Respiratory failureRespiratory failure Circulatory failure – less frequentCirculatory failure – less frequent

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Other ECG changesOther ECG changes

BradycardiaBradycardia ArrhythmiasArrhythmias Absence of a P waveAbsence of a P wave Wide QRS complexWide QRS complex T wave inversionT wave inversion

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Hypothermia – danger to healthHypothermia – danger to health

Persones living in cold, unheated and wet areasPersones living in cold, unheated and wet areas (spaces), defitient nutrition(spaces), defitient nutrition Iatrogenic hypothermia – anaesthesia inhibits Iatrogenic hypothermia – anaesthesia inhibits muscle shiveringmuscle shivering Professional damage – construction worker,Professional damage – construction worker, ship´s company, etc.ship´s company, etc. High altitude conditions – moutaineers,High altitude conditions – moutaineers, tourists, etc.tourists, etc. Rapid undercooling – in cold waterRapid undercooling – in cold water

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Hypothermia - etiology (1)Hypothermia - etiology (1)

Disturbances in warm creationDisturbances in warm creation CachexiaCachexia Endocrine disturbancesEndocrine disturbances Liver failureLiver failure Disturbances of thermoregulatory centreDisturbances of thermoregulatory centre Hypothalamus injuryHypothalamus injury Spinal cord injurySpinal cord injury Sever generalised disturbancesSever generalised disturbances

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Hypothermia – etiology (2)Hypothermia – etiology (2)

Sever vasculation disturbancesSever vasculation disturbances Generalised atherosclerosisGeneralised atherosclerosis M. M. BBüürger, collagenosisrger, collagenosis Cardiac diseases with hypokinetic circulationCardiac diseases with hypokinetic circulation Aortic stenosis, bradycardiaAortic stenosis, bradycardia OthersOthers Drugs - benzodiazepines, hypnotics, anaestheticsDrugs - benzodiazepines, hypnotics, anaesthetics Other substances - morphine, alcoholOther substances - morphine, alcohol

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Local influence of cold Local influence of cold frostbite (cheimetlon) frostbite (cheimetlon)

1. degree1. degree

arteriospasm – skin goes palearteriospasm – skin goes pale 2. degree 2. degree

transient vasodilatation and formationtransient vasodilatation and formation

of blistersof blisters 3. degree 3. degree

continued vasoconstriction – tissue necrosiscontinued vasoconstriction – tissue necrosis

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Hypothermia of limbs (extremity)Hypothermia of limbs (extremity)

Trench (fosse) legTrench (fosse) leg Combination of low temperature with prolongedCombination of low temperature with prolonged water expositionwater exposition Clinical picture:Clinical picture:1.1. Ischaemic stage Ischaemic stage with cold, paleness , cyanosis with cold, paleness , cyanosis (1-3 days)(1-3 days)2.2. Hyperaemic stage Hyperaemic stage – fulminating pain, oedema, – fulminating pain, oedema, red, hot skin with blisters, lymphangitis,red, hot skin with blisters, lymphangitis, gangrene (10 – 30 days)gangrene (10 – 30 days)3.3. Posthyperaemic stage Posthyperaemic stage with slow progressive with slow progressive adaptation, persisting paraesthaesiae,adaptation, persisting paraesthaesiae, hyperhidrosis and intolerance to cold hyperhidrosis and intolerance to cold

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Influence of increased surrouding Influence of increased surrouding temperature - hyperthermiatemperature - hyperthermia

Hyperthermia - overheatingHyperthermia - overheating Inability to quarantee heat output (expediture)Inability to quarantee heat output (expediture) Increase in body core temperature over 39Increase in body core temperature over 39OOCC Increase of oxygen tissue consumption Increase of oxygen tissue consumption Increase in protein, saccharide and fat catabolismIncrease in protein, saccharide and fat catabolism Increase in pulse and breathing frequencyIncrease in pulse and breathing frequency

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Hyperthermia – heat stroke (insolation)Hyperthermia – heat stroke (insolation)

Consequences:Consequences: VasodilatationVasodilatation - decrease in blood pressure, - decrease in blood pressure,

dizzness, colaps, even transient lossdizzness, colaps, even transient loss

of consciousnessof consciousness SweatingSweating - depletion of water and ionts, even - depletion of water and ionts, even

arrest of sweat productionarrest of sweat production Significant disability of CNS Significant disability of CNS -- loss of consciuosness,loss of consciuosness,

periodic breathing, crampsperiodic breathing, cramps

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Hyperthermia – insolation (siriasis)Hyperthermia – insolation (siriasis)

Initiated by direct sunlight on uncovered surface Initiated by direct sunlight on uncovered surface

of head and neckof head and neck Significantly influenced CNS function Significantly influenced CNS function

headache and vomitingheadache and vomiting Distinct disturbances of nervous functionsDistinct disturbances of nervous functions Unconciousness, hyperreflexia with tonicUnconciousness, hyperreflexia with tonic

clonic crampsclonic cramps

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HyperthermiaHyperthermia

Acute hyperthermiaAcute hyperthermia – syncope from heat – syncope from heat Subacute injurySubacute injury Instability of body core temperatureInstability of body core temperature Generalised weakness, vertigo, headache, tachycardia, Generalised weakness, vertigo, headache, tachycardia,

excessive vasomotor reactionsexcessive vasomotor reactions Muscle crampsMuscle cramps

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Chronic heat damage (warmth exhaustion)Chronic heat damage (warmth exhaustion)

In increased loss of liquids and exhaustion - weight loss, In increased loss of liquids and exhaustion - weight loss,

hypotonia, insomnia, tachycardia, strugglehypotonia, insomnia, tachycardia, struggle

dyspnoea dyspnoea Drop of libido, impotenceDrop of libido, impotence In tropic regions more often occurrence of skin diseasesIn tropic regions more often occurrence of skin diseases Drop in function of the sweat glands – intoleranceDrop in function of the sweat glands – intolerance

to heatto heat Heat caused muscle spasmsHeat caused muscle spasms

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Local effects of high temperature - fire injuriesLocal effects of high temperature - fire injuries

1. degree1. degree -- hyperaemia with light hyperaemia with light inflammatory responseinflammatory response 2. 2. degree -degree - exsudative inflammation, exsudative inflammation, developementdevelopement

of of blistersblisters 3. 3. degreedegree -- necrotic skin changes, necrotic skin changes, formationformation of ulcers of ulcers 4. 4. degreedegree – – carbonisationcarbonisation

GeneralGeneral symptoms depend on the amount of symptoms depend on the amount of body surface body surface

damage damage and the degree of burnsand the degree of burns..

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Atmospheric pressureAtmospheric pressure (1)(1)

Low pressureLow pressure1.1. AAcute cute altitudealtitude illness illness The symptoms during a quick climb come as late as The symptoms during a quick climb come as late as the second and third daythe second and third day HHeadache, eadache, aanorexia, fatigue, vertigo, insomnia, norexia, fatigue, vertigo, insomnia, dyspnoedyspnoe Causes: hypoxia, struggle, air temperature, previous Causes: hypoxia, struggle, air temperature, previous viral viral diseasedisease, , congenitalcongenital predispo predispossitionition

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2. Alpine pulmonary edema2. Alpine pulmonary edema Life threatening situations, which can, but needn´t be Life threatening situations, which can, but needn´t be

preceded by symptoms of acute alpine diseasepreceded by symptoms of acute alpine disease DyspnoeaDyspnoea - progressively ingravescenting, cough- progressively ingravescenting, cough,,

white sputum withwhite sputum with ocasional ocasional blood blood contentcontent The cause is not knownThe cause is not known - excessive hypoxic - excessive hypoxic

pulmonary vasoconstrictionpulmonary vasoconstriction

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3.3. Alpine brain Alpine brain ooedemaedema The most malignant formThe most malignant form Symptoms: strong headache, cerebSymptoms: strong headache, cerebellellaarr ataxia, ataxia,

irational behaviour, hairational behaviour, halllucinations, lucinations, ooedemaedema

of of papilla papilla Persistent vasodilatation and decreasing autoPersistent vasodilatation and decreasing auto--

regulation of brain circulationregulation of brain circulation

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High pressureHigh pressure

1.1. Scuba diving Scuba diving –– narcotic effect of nitrogen, toxic narcotic effect of nitrogen, toxic

hyperkapniahyperkapnia

2.2. DivingDiving – – drowning due to lack of oxygen for returndrowning due to lack of oxygen for return

to the surfaceto the surface

3.3. De Deccompresompression sion ((kesonkeson) ) diseasedisease – – the release the release

of dissolved gas bubbles in the tissues when of dissolved gas bubbles in the tissues when

suddenly ascenting, air embolussuddenly ascenting, air embolus

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Sickness from the effects of ioniSickness from the effects of ionissing ing radiationradiation

1.1. Acute disease from radiationAcute disease from radiation Genesis Genesis single, short term radiationsingle, short term radiation

of whole of whole body,body, or in the inner entry or in the inner entry

of radionuclids into the organism of radionuclids into the organism

in a dose bigger than 1 Gray (Gy)in a dose bigger than 1 Gray (Gy)

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Acute disease from radiationAcute disease from radiation (1)(1)

RadiobiologicRadiobiological al ef efffeecctt

depends on depends on physio physio - biological changes - biological changes

of cell structure, can lead to cellof cell structure, can lead to cell

apoptosisapoptosis or can or can cause a long term changecause a long term change

of their functionof their function LDLD5050 in healthy without treatment in healthy without treatment

2,7- 3 Gy to the2,7- 3 Gy to the center of the body. center of the body.

When the dose overcomes 4When the dose overcomes 4 -- 6 Gy,6 Gy, d deatheath

within 60 dayswithin 60 days..

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Acute disease from radiationAcute disease from radiation (2)(2)

Classification of clinical manifestation Classification of clinical manifestation

in connection to absorbed dosage:in connection to absorbed dosage:

Up to 0,25 GyUp to 0,25 Gy no clinical changes, anorexia and nausea no clinical changes, anorexia and nausea

in anamnesis in anamnesis 0,25 – 0,75 Gy0,25 – 0,75 Gy – blood account changes – blood account changes 1-10 Gy1-10 Gy – typical clinical picture, domination of haemo – – typical clinical picture, domination of haemo –

poetic disturbancespoetic disturbances

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Classification of clinical manifestationClassification of clinical manifestation

10-20 Gy10-20 Gy – – bowel formbowel form

bloody diarrhoea, bloody diarrhoea,

death 10.-14. daydeath 10.-14. day 20-80 Gy20-80 Gy – – toxemic formtoxemic form - oliguria, azotemia, - oliguria, azotemia,

metabolic acidosis,metabolic acidosis,

death 5. -7. daydeath 5. -7. day 80 Gy80 Gy – – nervous formnervous form - coma, - coma,

death within first hours or daysdeath within first hours or days

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Stages of acute radiation diseaseStages of acute radiation disease

Primary stage of general reaction Primary stage of general reaction

1- 5 days1- 5 days

fatigue, apathy, ataxia, vomiting, diarrhoeafatigue, apathy, ataxia, vomiting, diarrhoea

Latent stageLatent stage

over 6 Gy – not compulsory to be expressed, over 6 Gy – not compulsory to be expressed,

health status seemingly improvinghealth status seemingly improving

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Stage of fully developed clinical pictureStage of fully developed clinical picture

Stage of fully developed clinical pictureStage of fully developed clinical picture

weeks, months weeks, months

severe haemorrhagic diathesissevere haemorrhagic diathesis

with bleeding into mucouses, skin and organs, with bleeding into mucouses, skin and organs,

thrombocytopenia, thrombocytopenia,

infectious disease - pneumonia, infectious disease - pneumonia,

exhaustion and cachexia,exhaustion and cachexia,

myocarditis, cardio - vascular failuremyocarditis, cardio - vascular failure

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Stage of restoration to healthStage of restoration to health

Stage of recoveryStage of recovery

several months, up to 2 years several months, up to 2 years

persistence of fatigue syndrome persistence of fatigue syndrome

defficiency of cardio – vascular defficiency of cardio – vascular

and neuro - endocrine systemand neuro - endocrine system

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Acute radiation disease - helpAcute radiation disease - help

First aidFirst aid::

Basic first aidBasic first aid Situation analysis, radiation anamnesisSituation analysis, radiation anamnesis DeactivationDeactivation Blood and urine sample check Blood and urine sample check Hospital careHospital care

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Acute radiation disease - outcomesAcute radiation disease - outcomes

Permanent effects :Permanent effects :

Aplastic anaemiaAplastic anaemia LeukaemiaLeukaemia CataractCataract Genetic malfunctionsGenetic malfunctions Breast, pulmonary and thyreoid gland carcinomasBreast, pulmonary and thyreoid gland carcinomas

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Chronic radiation disease (1)Chronic radiation disease (1)

DevelopementDevelopement

repeated or chronic incidence of low dosesrepeated or chronic incidence of low doses of iono radiation exceeding permitted dosageof iono radiation exceeding permitted dosage

EffectsEffects

complicated clinical syndrome from different complicated clinical syndrome from different organ and system damageorgan and system damage long lasting fluctuant courselong lasting fluctuant course disease signs remain clinically silent for a long timedisease signs remain clinically silent for a long time

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Chronic radiation disease (2)Chronic radiation disease (2)

Effects:Effects: Long lasting local influence – skin and nail injury,Long lasting local influence – skin and nail injury, even spino - or basocellular carcinomaeven spino - or basocellular carcinoma Uranium mine workers – lung and larynx caUranium mine workers – lung and larynx ca Chronic inhalation of thorium oxide – pneumosclerosis Chronic inhalation of thorium oxide – pneumosclerosis Eye irradiation – cataractEye irradiation – cataract Agranulocytosis, aplastic anaemia, panmyelophysis,Agranulocytosis, aplastic anaemia, panmyelophysis, leukaemialeukaemia

Prevention:Prevention: Protection of workers and exposure monitoringProtection of workers and exposure monitoring

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Electric current and lightning damageElectric current and lightning damage Effects depend on :Effects depend on : Current characteristicsCurrent characteristics::a)a) TypeType AC 3x more dangerous than DC AC 3x more dangerous than DCb)b) IntensityIntensity danger from 25mA danger from 25mA 25 - 80mA passing through longer than 30s25 - 80mA passing through longer than 30s cardiac arrhytmia, fibrilation cardiac arrhytmia, fibrilation 80mA to 3A cardiac fibrilation after 0,3 s, over80mA to 3A cardiac fibrilation after 0,3 s, over 3A fibrilation and vital centres in prolonged3A fibrilation and vital centres in prolonged medulla irritated to eliminated, spasms, burns medulla irritated to eliminated, spasms, burns

c)c) TensionTension Electric resistenceElectric resistence of tissues and clothes of tissues and clothes EntranceEntrance and pathway of current through body and pathway of current through body TermTerm of contact of contact

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Electric current damage (1)Electric current damage (1)

Resistance of current passing through tissueResistance of current passing through tissue:: The lowest resistance along nerves and vessels, The lowest resistance along nerves and vessels,

then muscles, skin, tendons, fat and bonesthen muscles, skin, tendons, fat and bones The best conduction liquor and plasmaThe best conduction liquor and plasma THe biggest resistance skin and bonesTHe biggest resistance skin and bones

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Effects:Effects: ElectrothermicElectrothermic (AC) big amount of heat, burns (AC) big amount of heat, burns High skin resistanceHigh skin resistance local skin destruction local skin destruction

(hand, wrist, forearm and axilla damage)(hand, wrist, forearm and axilla damage) Low skin resistance Low skin resistance system and organ damage system and organ damage

(heart and brain) (heart and brain)

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Specific effectsSpecific effects:: Irritation of nerve endings spasms, breathing Irritation of nerve endings spasms, breathing

and cardiac activity arrestand cardiac activity arrest Acute kidney failureAcute kidney failure Tetanisation of limb muscles with generalisationTetanisation of limb muscles with generalisation

to other muscleto other muscle Passing through heart vessel spasms, musclePassing through heart vessel spasms, muscle

spasms with ventricular fibrilationspasms with ventricular fibrilation

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Specific effectsSpecific effects:: Passing through brain – loss of consciousness, electroPassing through brain – loss of consciousness, electro

shock, retrograde amnesia after unconsciousnessshock, retrograde amnesia after unconsciousness Posttraumatic stress reactionPosttraumatic stress reaction PolyneuropathyPolyneuropathy Autonomic NS dysfunctionAutonomic NS dysfunction Long bones, vertebrae fracturesLong bones, vertebrae fractures Electric cataractElectric cataract

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Lightning damageLightning damage

LightningLightning – mechanic electric discharge – mechanic electric discharge intensity 10 –20 kA, intensity 10 –20 kA, voltage 3 – 200 milion voltsvoltage 3 – 200 milion volts expansion of overheated airexpansion of overheated air effect of „pace“ voltage effect of „pace“ voltage up to 30 m from impact to the groundup to 30 m from impact to the groundEffects:Effects: Asystolia, less frequent ventricular fibrilationAsystolia, less frequent ventricular fibrilation Postburn syndrome and multiorgan damage Postburn syndrome and multiorgan damage with loss of consciousnesswith loss of consciousness

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Influence of chemical substances (1)Influence of chemical substances (1)

XenobioticsXenobiotics

Recieved in relatively low doses asRecieved in relatively low doses as

food, water and air contaminationfood, water and air contamination Actively recieved as Actively recieved as drugsdrugs Voluntary exposition Voluntary exposition to relatively toxic substances to relatively toxic substances

tobacco smoke, alcohol, drugstobacco smoke, alcohol, drugs

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Entry of xenobiotics into organismEntry of xenobiotics into organism

Mostly by breathing pathways, skin or digestive tractMostly by breathing pathways, skin or digestive tract Gas substancesGas substances – direct lung or other organs – direct lung or other organs influence, e.g. liver, influence, e.g. liver, CNS – gas solubility significance CNS – gas solubility significance Skin absorbtionSkin absorbtion – lipophilic and non polar substances – lipophilic and non polar substances pass through more easilypass through more easily GIT absorbtionGIT absorbtion – ability of lipophilic substances – ability of lipophilic substances pass through cell membranes, pass through cell membranes, biotransformation in liverbiotransformation in liver

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Xenobiotic effects mechanismXenobiotic effects mechanism

Substance interaction with receptorsSubstance interaction with receptors

receptor activation (morphine, heroin)receptor activation (morphine, heroin)

or antagonistic influence or antagonistic influence

(DDT – receptor antagonist for testosterone)(DDT – receptor antagonist for testosterone) Interference with membranes processesInterference with membranes processes

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Enzyme inhibitionEnzyme inhibition reversible nebo irreversible, reversible nebo irreversible, competetive or non-competetive molecular competetive or non-competetive molecular bond (CO link to hemoglobin, bond (CO link to hemoglobin, oxygen displacement)oxygen displacement) Influence onInfluence on energetic cell metabolism energetic cell metabolism and intracellular calcium leveland intracellular calcium level Oxygenative stressOxygenative stress free radicals reaction (paracetamol)free radicals reaction (paracetamol) Combined mechanismsCombined mechanisms

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Specific xenobiotic influences – examplesSpecific xenobiotic influences – examples Nitrates and nitritesNitrates and nitrites – methaemoglobinaemia – methaemoglobinaemia in newbornsin newborns Harmful air substancesHarmful air substances – sulphure dioxide, – sulphure dioxide, nitrogen oxides and dust nitrogen oxides and dust Tobbacco smokeTobbacco smoke – nikotine (vasoconstriction in CNS, – nikotine (vasoconstriction in CNS, tachycardia, blood pressure increase),tachycardia, blood pressure increase), nitrosamins, polyaromatic hydrocarbonsnitrosamins, polyaromatic hydrocarbons (cancerogenous), carbon monooxide (cancerogenous), carbon monooxide (high affinity to haemoglobin)(high affinity to haemoglobin) DrugsDrugs

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Unhealthy building syndrome (1)Unhealthy building syndrome (1)

Originally in closed climatised industrial building workers, Originally in closed climatised industrial building workers, event. occurrence even without professional load.event. occurrence even without professional load.

Etiology:Etiology: Fugitive organic Fugitive organic soulventssoulvents aldehydes, formaldehyde,.. soulvents from aldehydes, formaldehyde,.. soulvents from water soluble colours - glycol, ammonia,..water soluble colours - glycol, ammonia,.. General dustfallGeneral dustfall dust from biological remanences - animal fur,dust from biological remanences - animal fur, fell, mites,.. fell, mites,.. smoke,..smoke,..

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Acute effectsAcute effects::

Conjunctiva, mucosaes, upper airwayes ador Conjunctiva, mucosaes, upper airwayes ador Dryness and irritation of skin Dryness and irritation of skin Cephalgia, fatique, irritability, nauseaCephalgia, fatique, irritability, nausea Nasal bleeding Nasal bleeding Breathing difficulties Breathing difficulties Mass psychogenic disease Mass psychogenic disease chain incidence of dyscomfort induced,chain incidence of dyscomfort induced, for example, by unanccountable smell for example, by unanccountable smell

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Later effects:Later effects:

Radon influence from building materials on lungs Radon influence from building materials on lungs Ionizing radiation influence from strata (lower beds)Ionizing radiation influence from strata (lower beds) Cancerous influences (more pronounced in smokers)Cancerous influences (more pronounced in smokers)

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Enforce of pfysical, chemical and biological factors in pathogenesis of diseases

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