Enzymes are protein catalysts that support biochemical reactions in cells and tissues. They have active sites that substrates must fit into in order to undergo reaction. Enzymes are classified based on their reactions and components. Some require coenzymes like B vitamins or metal ions. Enzyme activity is affected by factors like substrate, enzyme, and product concentration; temperature; pH; and presence of activators or inhibitors. Clinical enzyme tests can indicate tissue damage, such as elevated liver enzymes in hepatitis or muscle enzymes in infarction. Together with other markers, enzymes help diagnose and monitor various conditions.
An enzyme is a biological catalyst and is almost always a protein. It speeds up the rate of a specific chemical reaction in the cell. The enzyme is not destroyed during the reaction and is used over and over.
This ppt describes the overview of enzyme regulation and Allosterism. Presented since October 23,2017GC at Addis Ababa University, School of Medicine, Department of medical biochemistry.
"Bacterial metabolism: Fueling life's processes in tiny powerhouses."
Use of bacterial metabolism in biotechnology, biofuels, and other industries
Examples of how bacterial metabolism is harnessed for beneficial purposes
"Metabolism: the sum of chemical reactions in an organism, supporting growth, energy production, and vital functions."
"Bacterial Metabolism and Life: Pervading every aspect of life, shaping ecosystems, and influencing our world."
Bacterial metabolism refers to the collective chemical reactions and processes that occur within bacterial cells, enabling them to maintain life, grow, and reproduce. These metabolic activities involve a complex network of biochemical pathways that facilitate the conversion of nutrients into energy, biomolecules, and essential compounds necessary for bacterial survival.
Metabolic processes in bacteria include catabolic pathways that break down complex molecules (such as sugars) to release energy and anabolic pathways that build complex molecules (such as proteins, nucleic acids) using energy. Bacteria utilize various metabolic strategies based on their energy and carbon sources, including aerobic and anaerobic respiration, fermentation, and photosynthesis in photosynthetic bacteria.
The primary goals of bacterial metabolism are to obtain energy, synthesize necessary cellular components, regulate chemical processes, and adapt to changing environmental conditions. The understanding of bacterial metabolism is crucial for various fields, including medicine, agriculture, biotechnology, and environmental science, as it allows us to develop strategies to combat harmful bacteria, harness their metabolic capabilities for beneficial applications, and study their role in ecological systems.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
An enzyme is a biological catalyst and is almost always a protein. It speeds up the rate of a specific chemical reaction in the cell. The enzyme is not destroyed during the reaction and is used over and over.
This ppt describes the overview of enzyme regulation and Allosterism. Presented since October 23,2017GC at Addis Ababa University, School of Medicine, Department of medical biochemistry.
"Bacterial metabolism: Fueling life's processes in tiny powerhouses."
Use of bacterial metabolism in biotechnology, biofuels, and other industries
Examples of how bacterial metabolism is harnessed for beneficial purposes
"Metabolism: the sum of chemical reactions in an organism, supporting growth, energy production, and vital functions."
"Bacterial Metabolism and Life: Pervading every aspect of life, shaping ecosystems, and influencing our world."
Bacterial metabolism refers to the collective chemical reactions and processes that occur within bacterial cells, enabling them to maintain life, grow, and reproduce. These metabolic activities involve a complex network of biochemical pathways that facilitate the conversion of nutrients into energy, biomolecules, and essential compounds necessary for bacterial survival.
Metabolic processes in bacteria include catabolic pathways that break down complex molecules (such as sugars) to release energy and anabolic pathways that build complex molecules (such as proteins, nucleic acids) using energy. Bacteria utilize various metabolic strategies based on their energy and carbon sources, including aerobic and anaerobic respiration, fermentation, and photosynthesis in photosynthetic bacteria.
The primary goals of bacterial metabolism are to obtain energy, synthesize necessary cellular components, regulate chemical processes, and adapt to changing environmental conditions. The understanding of bacterial metabolism is crucial for various fields, including medicine, agriculture, biotechnology, and environmental science, as it allows us to develop strategies to combat harmful bacteria, harness their metabolic capabilities for beneficial applications, and study their role in ecological systems.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
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NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
2. Enzyme
Definition
• Enzymes are protein catalyst produced by a cell and responsible ‘for the high
rate’ and specificity of one or more intracellular or extracellular biochemical
reactions.
• Enzymes are biological catalysts responsible for supporting almost all of the
chemical reactions that maintain animal homeostasis. Enzyme reactions are
always reversible.
• The substance, upon which an enzyme acts, is called as substrate. Enzymes
are involved in conversion of substrate into product.
3. Enzyme
Characteristics
• The basic characteristics of enzymes includes
• (i) Almost all the enzymes are proteins and they follow the physical and
chemical reactions of proteins
• (ii) Enzymes are sensitive and labile to heat
• (iii) Enzymes are water soluble
• (iv) Enzymes could be precipitated by protein precipitating agents such as
ammonium sulfate and trichloroacetic acid.
4. Each enzyme has an
“active site.” This area
has a unique shape.
The substance an
enzyme works on is a
substrate. The
substrate also has a
unique shape. The
enzyme and the
substrate must fit
together to work.
5. Enzymes
Classification
• Currently enzymes are grouped into six functional classes by
the International Union of Biochemists and Molecular Biology
(IUBMB). As per the IUBMB system, each enzyme name starts
with EC (enzyme class) followed by 4 digits.
• The first digit represents the class, the second digit strands for
the subclass, the third digit represents the sub-subclass or
subgroup and the fourth digit provides the particular enzyme
6.
7. Enzymes
Classification
• Enzymes are also classified on the basis of their composition. Enzymes composed wholly of
protein are known as simple enzymes in contrast to complex enzymes, which are composed
of protein plus a relatively small organic molecule.
• Complex enzymes are also known as holo-enzymes. The non- protein component of an
enzyme may be as simple as a metal ion or as complex as a small non-protein organic
molecule.
• Enzymes that require a metal in their composition are known as metalloenzymes.
Metalloenzymes bind and retain their metal atom(s) under all conditions with very high affinity.
• Enzymes with lower affinity for metal ion, but still require the metal ion for activity, are known
as metal-activated enzymes.
8. Enzymes
Classification
• Based on requirement of ATP, enzymes are further classified into two types namely
synthetases and synthase.
• Synthetases are ATP- dependent enzymes catalyzing biosynthetic reactions.
Synthetases are enzyme belong to the class 6 (Ligases). Enzymes such as
Carbamoyl phosphate synthetase, Arginino succinate synthetase and Glutamine
synthetase are examples of the synthetases group of enzymes. The enzyme class
other than ligases includes synthases.
• Synthases group of enzymes involves in catalyzing biosynthetic reactions that do
not require ATP directly. Enzymes such as glycogen synthase and Alanine synthase
are examples of synthase group.
9. Coenzyme
Definition
• Enzymes may be simple proteins, or complex enzymes. A complex enzyme
contains a non-protein part, called as prosthetic group (co-enzymes). Co-
enzymes are heat stable low molecular weight organic compound.
• The combined form of protein and the co-enzyme are called as holo-enzyme.
• The heat labile or unstable part of the holo-enzyme is called as apo-enzyme.
The apo-enzyme gives necessary three dimensional structures required for the
enzymatic chemical reaction. Co-enzymes are very essential for the biological
activities of the enzyme.
• Most of the co-enzymes are derivatives of vitamin B complex
10. Coenzyme
Definition
• Co-enzymes are further divided into two groups. The first groups of co-
enzymes are a part of reaction catalyzed by oxidoreductase by
donating or accepting hydrogen atoms or electrons. The first
group of co-enzymes are also called as co-substrates or secondary
substrates. Because they are involved in counter- balance in change
occurring in the substrate.
• The second group of co-enzymes involves in reactions transferring
groups other than hydrogen.
11. Enzymes
Factors affecting Enzyme Activity
• Velocity or rate of enzymatic reaction is assessed by the rate of change in concentration of
substrate or product at a given time duration. Various factors which affect the activity of
enzymes include:
• 1. Substrate concentration
• 2. Enzyme concentration
• 3. Product concentration
• 4. Temperature
• 5. Hydrogen ion concentration (pH)
• 6. Presence of activators
• 7. Presence of inhibitor
12. Enzymes
Factors affecting Enzyme Activity
• Effect of substrate Concentration
• Reaction velocity of an enzymatic process increases with constant enzyme
concentration and increase in substrate concentration.
• Effect of enzyme Concentration
• As there is optimal substrate concentration, rate of an enzymatic reaction or velocity
(V) is directly proportional to the enzyme concentration
13. Enzymes
Factors affecting Enzyme Activity
• Effect of product concentration
• In case of a reversible reaction catalyzed by a enzyme, as per the law of mass action
the rate of reaction is slowed down with equilibrium. So, rate of reaction is slowed,
stopped or even reversed with increase in product concentration.
• Effect of temperature
• Velocity of enzymatic reaction increases with temperature of the medium which they
are most efficient and the same is termed as optimum temperature. As temperatures
increases it leads to denaturation; a molecular arrangement which causes a loss of the
active sites of the enzyme surfaces and results in a loss of efficiency.
14. Enzymes
Factors affecting Enzyme Activity
• Effect of temperature
• Like temperature, all enzymes have a optimum pH, at which the enzymatic activity will
be at maximum. Many enzymes are most efficient in the region of pH 6-7, which
is the pH of the cell. Outside this range, enzyme activity drops off very rapidly.
Reduction in efficiency caused by changes in the pH is due to changes in the degree
of ionization of the substrate and enzyme. Highly acidic or alkaline conditions
bring about a denaturation and subsequent loss of enzymatic activity. Some
exceptions such as pepsin (with optimum pH 1-2), alkaline phosphatase (with
optimum pH 9-10) and acid phosphatase (with optimum pH 4-5) are even noticed.
15. Enzymes
Factors affecting Enzyme Activity
• Presence of activators
• Presence of certain inorganic ions increases the activity of enzymes. The best examples are chloride ions activated
salivary amylase and calcium activated lipases.
• Effect of Inhibitors
• The catalytic enzymatic reaction may be inhibited by substances which prevent the formation of a normal enzyme-
substrate complex. The level of inhibition then depends entirely upon the relative concentrations of the true
substrate and the inhibitor. Such inhibition, which depends on competition with the substrate for the active sites of
the enzyme, is termed competitive inhibition. In other cases, the inhibitor combines with the enzyme-substrate
complex to give an inactive enzyme-substrate-inhibitor complex, which cannot undergo further reaction to give the
usual product. This is termed uncompetitive inhibition. Non competitive inhibition involves combination of the
inhibitor with the enzyme or the enzyme substrate complex, to give inactive complexes. In this case, the inhibitor
binds to sites, on the enzyme other than enzyme sites, resulting in deformation of the enzyme molecule so that the
formation of the enzyme- substrate complex is slower than normal
16.
17.
18. Enzymes
CLINICAL SIGNIFICANCE OF ENZYMES
• The measurement of enzymes level in serum is
applied in diagnostic application. Detection of certain
enzymes in the serum indicates that tissue or cellular
damage has occurred resulting in the release of
intracellular components into the blood.
19. Enzymes
CLINICAL SIGNIFICANCE OF ENZYMES
• Pancreatic Enzymes Acute pancreatitis is an inflammatory process where auto digestion of gland
was noticed with activation of the certain pancreatic enzymes. Enzymes which involves in
pancreatic destruction includes α-amylase, lipase etc.,
• α-amylase α-amylase (AMYs) are calcium dependent hydrolyase class of metaloenzyme The
normal values of amylase is in range of 28-100 U/L. Marked increase of 5 to 10 times the upper
reference limit (URL) in AMYs activity indicates acute pancreatitis and severe glomerular
impairment.
• Lipase is single chain glycoprotein . Bile salts and a cofactor called colipase are required for full
catalytic activity of lipase. Colipase is secreted by pancreas. Lipase is small molecule filtered
through the glomerulus and totally reabsorbed by the renal tubules. Lipase is not normally detected
in urine samples. The normal value of lipase ranges from 40-200 U/ L. Increase in plasma lipase
activity indicates acute pancreatitis and carcinoma of the pancreas. So determination of both
amylase and lipase together helps in the diagnosis of acute pancreatitis.
20. Enzymes
CLINICAL SIGNIFICANCE OF ENZYMES
• Liver Enzymes The assay of serum enzymes is very useful for the
differential diagnosis and monitoring of various liver disorders. Liver
enzymes acts as marker of hepatocellular damage, cholestasis and
disturbances in the hepatocellular synthesis.
• Markers of Hepatocellular Damage In case of hepatocellular
damage, the enzymes which are normally present inside the
hepatocytes are released into the blood. Aminotransaminases
such as aspartate transaminase (AST) and alanine
transaminase (ALT) are routinely used in diagnosis of
hepatocellular damages.
21. Enzymes
CLINICAL SIGNIFICANCE OF ENZYMES
• Aspartate transaminase (AST) Aspartate transaminase is present in high
concentrations in cells of cardiac and skeletal muscle, liver, kidney and erythrocytes.
Damage to any of these tissues may increase plasma AST levels. The normal value of
AST for male is <35 U/ L and for female it is <31 U/L. Marked increase of AST activity in
the range of 10 to 100 times the upper adult reference limit indicates myocardial
infarction or acute viral or toxic hepatitis.
• Alanine transaminase (ALT) Alanine transaminase is present at high
concentrations in liver and to a lesser extent, in skeletal muscle, kidney and heart.
Thus in case of liver damage increase in both AST and ALT were noticed. While in
myocardial infarction AST is increased with little or no increase in ALT. The normal value
of ALT is <45 U/L and <34 U/L for male and female respectively. In acute viral hepatitis
there is a 100-1000 times increase in both ALT and AST but ALT level is increased more
than that of AST.
22. Enzymes
CLINICAL SIGNIFICANCE OF ENZYMES
• 3 Muscle Enzymes Clinically important muscle enzymes include creatine kinase and lactate dehydrogenase.
• Creatine kinase (CK) is most abundant in cells of brain, cardiac and skeletal. In addition to their abundance in above
tissues, it also occurs in other tissues such as smooth muscle. In normal physiological condition the CK activity is 46171
U/L (for male) and 34-145 U/L (for female). Serum CK level elevates in all types of muscular dystrophy. Quite high values
of CK are noted in viral myositis, polymyositis and similar muscle disease. Under the circumstances of neurogenic muscle
disease such as: myasthenia gravis, multiple sclerosis and Parkinsonism, the level of serum CK is normal. CK consist of
two protein subunits, M (for muscle) and B (for brain) and exist as three different isoforms namely BB (CK-1), MB (CK-2)
and MM (CK-3). CK-MM is the predominant isoenzyme in skeletal and cardiac muscle and is detectable in the plasma of
normal subjects. CK-BB is present in high concentrations in the brain and in the smooth muscle of the gastrointestinal and
genital tracts.
• Lactate dehydrogenase (LD) catalyses the reversible interconversion of lactate and pyruvate. LD has a molecular weight
of 134 kDa and is widely distributed in the body, with high concentrations in cells of cardiac and skeletal muscle, liver,
kidney, brain and erythrocytes. Five isoforms (LD-1 to LD-5) of LD are existing. The normal physiological limit of LD is 180-
360 U/L.
• Other clinically important enzymes includes acid phosphatase, glucose -6phosphate dehydrogenase, cystathionine α-
synthase and sphingomyelinase.