Carbohydrates are digested in the mouth by salivary amylase and in the small intestine by pancreatic amylase and intestinal enzymes. Monosaccharides like glucose are absorbed into the bloodstream through active transport involving sodium-glucose transporters in the intestinal walls. Glucose is the primary fuel for cells and its uptake is mediated by glucose transporters, especially GLUT2 and GLUT4 which are regulated by insulin. Deficiencies in disaccharide-digesting enzymes can cause issues like lactose intolerance and related symptoms.
Class 1 digestion and absorption of carbohydrateDhiraj Trivedi
Dr. Dhiraj J. Trivedi presenting Lecture on Carbohydrate metabolism for medical students.
Professor, SDM College of Medical Sciences, Dharwad, Karnataka, India
Digestion and absorption of lipids ppt
what is lipid ppt
digestion of lipid ppt
phase of digestion and absorption ppt
phases of lipids ppt
digestion in mouth and stomach ppt
digestion in small intestine ppt
secretion of lipids ppt
enzyme involved in lipid digestion ppt
transportation phases of lipids ppt
principles of lipid digestion ppt
These are major source of energy for living organisms.
Supplying a huge array of metabolic intermediates for biosynthetic reactions.
The structural elements in cell coat or connective tissues.
In this section, we describe digestion and absorption of proteins.
Most of the slides are cited from:
1. Lippincott's Illustrated Review Biochemistry
2. U. Satyrana Biochemistry
Dr. Haroon
Absorption of proteins ppt
composition of protein ppt
digestion of protein ppt
Absorption of protein ppt
absorption of amino acid ppt
function of protein ppt
amino acid ppt
role enzyme ppt
Class 1 digestion and absorption of carbohydrateDhiraj Trivedi
Dr. Dhiraj J. Trivedi presenting Lecture on Carbohydrate metabolism for medical students.
Professor, SDM College of Medical Sciences, Dharwad, Karnataka, India
Digestion and absorption of lipids ppt
what is lipid ppt
digestion of lipid ppt
phase of digestion and absorption ppt
phases of lipids ppt
digestion in mouth and stomach ppt
digestion in small intestine ppt
secretion of lipids ppt
enzyme involved in lipid digestion ppt
transportation phases of lipids ppt
principles of lipid digestion ppt
These are major source of energy for living organisms.
Supplying a huge array of metabolic intermediates for biosynthetic reactions.
The structural elements in cell coat or connective tissues.
In this section, we describe digestion and absorption of proteins.
Most of the slides are cited from:
1. Lippincott's Illustrated Review Biochemistry
2. U. Satyrana Biochemistry
Dr. Haroon
Absorption of proteins ppt
composition of protein ppt
digestion of protein ppt
Absorption of protein ppt
absorption of amino acid ppt
function of protein ppt
amino acid ppt
role enzyme ppt
This lecture talking about; Digestion hydrolysis of large and complex organic molecules of foodstuffs into smaller and preferably water-soluble molecules which can be easily absorbed by the GIT.
Carbohydrates (also called carbs) are a type of macronutrient found in certain foods and drinks. Sugars, starches and fiber are carbohydrates. Other macronutrients include fat and protein. Your body needs these macronutrients to stay healthy.
Digestion & absorption of carbohydrate.pptxABHIJIT BHOYAR
The goal of carbohydrate digestion is to break down all disaccharides and complex carbohydrates into monosaccharides for absorption, although not all are completely absorbed in the small intestine (e.g., fiber). Digestion begins in the mouth with salivary amylase released during the process of chewing.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
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.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
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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
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
2. Digestion is a process involving the hydrolysis of large
and complex organic molecules of foodstuffs into smaller
and preferably water-soluble molecules which can be
easily absorbed by the GIT for utilization by the organism
Digestion of macromolecules also promotes the
absorption of fat soluble vitamins and certain minerals
3. The principal dietary carbohydrates are polysaccharides
(starch, glycogen) disaccharides (lactose, sucrose) &
monosaccharides (glucose, fructose)
The digestion of carbohydrates occurs in the mouth &
intestine
The hydrolysis of glycosidic bonds is carried out by a group
of enzymes called glycosidases
10. Digestion in mouth:
Saliva contains carbohydrate splitting enzyme salivary
amylase (ptyalin)
Action of salivary amylase (ptyalin):
It is α – amylase, requires Cl- ions for activation & optimum
pH 6.7 (6.6 to 6.8)
Salivary amylase hydrolyses α 1-4 glycosidic bonds of
polysaccharides, producing smaller molecules maltose,
glucose & trisaccharide, maltotriose
11. Salivary amylase action stops in stomach when pH falls to 3.0
Digestion in stomach:
No carbohydrate splitting enzyme in gastric juice
Some dietary sucrose may be hydrolysed to equimolar
amounts of glucose & fructose by HCL
Digestion in duodenum:
Food bolus in duodenum mixes with pancreatic juice
Pancreatic juice contains pancreatic amylase, similar to
salivary amylase
12. Action of pancreatic amylase:
It is an α-amylase, optimum pH 7.1, requires Cl- ions
It specifically hydrolyzes α1-4 glycosidic bonds & not on
a1-6 bonds
It produces disaccharides (maltose, isomaltose) &
oligosaccharides
The final digestion of di- & oligosaccharides to
monosaccharides primarily occurs at the mucosal lining
of the upper jejunum
13. Carried out by oligosaccharidases (e.g. glucoamylase acting
on amylose) and disaccharidases (e.g. maltase, sucrase,
lactase)
Digestion in small intestine:
Action of intestinal juice:
Intestinal amylase: It hydrolyses terminal a 1-4-glycosidic
bonds in polysaccharides & oligosaccharides, liberating free
glucose
Lactase: It is β-galactosidase, its pH range 5.4 to 6.0
Lactose is hydrolysed to glucose & galactose
14. Isomaltase:
It catalyses a 1-6 glycosidic bonds, branching points,
producing maltose & glucose
Maltase:
It hydrolyses a 1-4-glycosidic bonds between glucose
units in maltose & its pH range is 5.8 to 6.2
Sucrase:
It hydrolyses sucrose to glucose & fructose
Its pH range is 5.0 to 7.0
15.
16.
17. Absorption of carbohydrates
The principal monosaccharides produced by the digestion
of carbohydrates are glucose, fructose and galactose
Glucose accounts for 80% of the total monosaccharides
The absorption occurs mostly in the duodenum & upper
jejunum of small intestine
Only monosaccharides are absorbed by the intestine
Absorption rate is maximum for galactose; moderate for
glucose; and minimum for fructose
18. Absorption rates
Cori study:
He studies the rate of absorption of different sugars from
small intestine in rat
Glucose absorption as 100, comparative absorption of other
sugars as
Galactose=110, Glucose=100, Fructose=43, Mannoase=19,
Xylose=15 & Arabinose=9
Galactose is absorbed more rapidly than glucose
Pentoses are absorbed slowly
19. Mechanism of absorption
Different sugars possess different mechanisms for
their absorption
Glucose is transported into the intestinal mucosal cells
by a carrier mediated and energy requiring process
20. Monosaccharides, the end products of carbohydrate
digestion, enter the capillaries of the intestinal villi
In the liver,
galactose &
fructose are
converted to
glucose.
Small intestine
Monosaccharides travel to
the liver via the portal vein.
22. Active transport mechanism
Glucose and Na+ share the same transport system (symport)
referred to as sodium dependent glucose transporter
The concentration of Na+ is higher in the intestinal lumen
compared to mucosal cells
Na+ moves into the cells along its concentration gradient &
simultaneously glucose is transported into the intestinal cells
Mediated by the same carrier system
23. Na+ diffuses into the cell and it drags glucose along with it
The intestinal Na+ gradient is the immediate energy source
for glucose transport
This energy is indirectly supplied by ATP since the re-entry of
Na+ (against the concentration gradient) into the intestinal
lumen is an energy requiring active process
The enzyme Na+-K+ ATPase is involved in the transport of
Na+ in exchange of K+ against the concentration gradient
24. Intestinal absorption of glucose
At the intestinal lumen, absorption is by SGluT & at the blood
vessel side, absorption is by GluT2
25. SGluT: Sodium and glucose co-transport system at
luminal side; sodium is then pumped out
26. Oral rehydration therapy (ORT):
ORT is common treatment of diarrhoea
Oral rehydration fluid contains glucose & sodium
Intestinal absorption of sodium is facilitated by the
presence of glucose
Mechanism of absorption of galactose is similar to that of
glucose
Phlorozin blocks the Na+ dependent transport of glucose &
galactose
27. Glucose transporters
Glucose transporters GluT-1 to 7 have been described in
various tissues
GluT-2 & GluT-4 are very important
GluT-2:
Operates in intestinal epithelial cells
It is a uniport system & not dependent on Na+ ions
Glucose is held on GluT-2, by weak hydrogen bonds
After fixing glucose, changes configuration & opens inner
side releasing glucose
28. GluT-4:
Operates in the muscle & adipose tissue
GluT-4 is under control of insulin
Insulin induces the intracellular GluT-4 molecules to move
to the cell membrane & increases the uptake
Other “GluT” molecules are not under control of insulin
GluT-1 is present in RBCs & brain
Also present in retina, colon, placenta
It helps in glucose uptake in most of these tissues which
is independent of insulin
30. Glucose transporters
Transporter Present in Properties
GluT1
RBC, brain, kidney, colon,
retina, placenta
Glucose uptake in most of cells
GluT2
Surface of intestinal cells, liver,
β-cells of pancreas
Low affinity; glucose uptake in liver;
glucose sensor in β-cells
GluT3
Neurons, brain High affinity; glucose into brain cells
GluT4
Skeletal, heart muscle,
adipose tissue
Insulin mediated glucose uptake
GluT5
Small intestine, testis,
sperms, kidney
Fructose transporter; poor ability to
transport glucose
GluT7 Liver endoplasmic reticulum Glucose from ER to cytoplasm
SGluT Intestine, kidney Cotransport; from lumen into cell
31. Absorption of fructose:
Fructose absorption is simple
Does not require energy and Na+ ions
Transported by facilitated diffusion mediated by a carrier
Inside the epithelial cell, most of the fructose is converted
to glucose
The latter then enters the circulation
Pentoses are absorbed by a process of simple diffusion
32. Factors influencing rate of absorption
Mucus membrane:
Mucus membrane is not healthy, absorption will decrease
Thyroid hormones:
Increases absorption of hexoses & act on intestinal mucosa
Adrenal cortex: Absorption decreases in adrenocortical
deficiency, mainly due to decreased concentration of sodium
Anterior pituitary: It affects mainly through thyroid hormones
33. Insulin:
It has no effect on absorption of glucose
Vitamins:
Absorption is decreased in B-complex vitamins
deficiency-thiamine, pyridoxine, pantothenic acid
Inherited deficiency of sucrase & lactase enzymes
interfere with corresponding disaccharide absorption
34. Abnormalities of carbohydrate digestions
Defect in disaccharidases results in the passage of undigested
disaccharides into the large intestine
The disaccharides draw water from the intestinal mucosa by
osmosis and cause osmotic diarrhoea
Bacterial action of these undigested carbohydrates leads to
flatulence
Flatulence is characterized by increased intestinal motility,
cramps and irritation
35. The carbohydrates (di, oligo and polysaccharides) not
hydrolysed by α-amylase
The di & oligosaccharides can be degraded by the bacteria
present in ileum to liberate monosaccharides
During the course of utilization of monosaccharides by the
intestinal bacteria, the gases such as hydrogen, methane &
carbon dioxide-besides lactate and short chain fatty acids
are released & causes flatulence
36. The occurrence of flatulence after the ingestion of
leguminous seeds (bengal gram, redgram, beans, peas,
soya bean) is very common
They contain several non-digestible oligonccharides by
human intestinal enzymes
These compounds are degraded and utilised by intestinal
bacteria causing flatulence
Raffinose containing galactose, glucose and fructose is a
predominant oligosaccharide found in leguminous seeds
37. Lactose intolerance
lactase (β-galactosidase) deficiency is the most common
disaccharidase deficiency in humans
lt is estimated that more than half of the world's adult
population is affected by lactose intolerance
Some infants may have deficiency of lactase & they show
intolerance to lactose, the milk sugar
Symptoms:
Diarrhoea, flatulence, abdominal cramps
38. Discussion:
Lactose of milk cannot be hydrolysed due to deficiency of
lactase
Accumulation of lactose in intestinal tract, which is
“osmotically active” & holds water, producing diarrhoea.
Accumulated lactose is also fermented by intestinal
bacteria which produce gas & other products, producing
flatulence & abdominal pain
39. Sucrase deficiency:
Inherited deficiency of sucrose
Symptoms occurs in early childhood with ingestion of sugars,
sucrose
Symptoms: Diarrhoea, flatulence, abdominal cramps
Disacchariduria:
Increase in the excretion of disaccharides may be observed in
some patients with disaccharidase deficiency
Observed in intestinal damage, celiac diseases
40. Reference books
Textbook of Biochemistry - Dr.U.Satyanarayana
Textbook of Biochemistry - DM.Vasudevan
Textbook of Medical Biochemistry - MN Chatterjea