Ageing is a gradual process that takes place over many decades. Most theories of ageing relate to impaired DNA replication and loss of cell viability and hence the viability of the body’s organs. Ageing is often accompanied by socioeconomic changes that can have a great impact on the nutritional needs and status of elderly individuals. The incidence of disability increases with ageing, with over a third of the elderly population limited by chronic conditions and unable to carry on normal daily living activity
ROle of selenium, Zinc in the eye, functions of zinc and selenium in the eye, Zn and the antioxidant mechanisms of eye General nutritional fact of calcium and its role in the body
Retinal Rhodopsin and its function in the eye, Crystalline proteins and its age-related degeneration, Kwashiorkor and xerophthalmia and other eye problems, Cornea in Kwashiorkor
Types of fat, transportation of fat in the blood, FUnction of fat in the diet, DHA accumulation in the eye, Disc shedding in the retina, DHA conservation in eye, Role of DHA in the eye
ROle of selenium, Zinc in the eye, functions of zinc and selenium in the eye, Zn and the antioxidant mechanisms of eye General nutritional fact of calcium and its role in the body
Retinal Rhodopsin and its function in the eye, Crystalline proteins and its age-related degeneration, Kwashiorkor and xerophthalmia and other eye problems, Cornea in Kwashiorkor
Types of fat, transportation of fat in the blood, FUnction of fat in the diet, DHA accumulation in the eye, Disc shedding in the retina, DHA conservation in eye, Role of DHA in the eye
Vitamin A-intoduction, functions, sources, storage, WHO statistics, deficiency, treatment, prevention and control of deficiencies, Vit. A deficiency in India, assessment of Vit. A deficiency, recommended allowances, toxicity.
Vitamin A, Digestion, absorption, transport, Functions and requirement and deficiency ad eye relate problems.
Vitamin C, Functions, requiremnts, deficiency
Vitamin E, defciency and eye
Management of visual problems of Aging by Ashith Tripathi Ashith Tripathi
This presentation contains headings - Visual performance in the ageing eye
Routine optometric and ocular examination of an older adult:
History
Ocular health examination
Visual acuity measurement
Refraction
Binocular vision
Visual field measurement
Colour vision
Management of vision problems in older adults
Frame requirement
Lens requirements
And special instructions etc.
These are various structures in an eye , which are changing with age.
# ocular adnexa/ eyelids
# eyelashes / eyelid margin
# tear film
# cornea
# conjunctiva
# anterior chamber
# ciliary body
# pupil /iris
# crystalline lens
# vitreous
# choroid
# retina
Vitamin A-intoduction, functions, sources, storage, WHO statistics, deficiency, treatment, prevention and control of deficiencies, Vit. A deficiency in India, assessment of Vit. A deficiency, recommended allowances, toxicity.
Vitamin A, Digestion, absorption, transport, Functions and requirement and deficiency ad eye relate problems.
Vitamin C, Functions, requiremnts, deficiency
Vitamin E, defciency and eye
Management of visual problems of Aging by Ashith Tripathi Ashith Tripathi
This presentation contains headings - Visual performance in the ageing eye
Routine optometric and ocular examination of an older adult:
History
Ocular health examination
Visual acuity measurement
Refraction
Binocular vision
Visual field measurement
Colour vision
Management of vision problems in older adults
Frame requirement
Lens requirements
And special instructions etc.
These are various structures in an eye , which are changing with age.
# ocular adnexa/ eyelids
# eyelashes / eyelid margin
# tear film
# cornea
# conjunctiva
# anterior chamber
# ciliary body
# pupil /iris
# crystalline lens
# vitreous
# choroid
# retina
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com
Elderly Assignment Due Tuesday, November 29, 201125 points + 15 .docxjack60216
Elderly Assignment Due Tuesday, November 29, 2011
25 points + 15 points for educational material
Older Adult Assignment
I. Interview an older adult (70 years or older) regarding changes in food habits over the years.
· What foods did they eat as a youngster? Why?
· What foods are they eating now? Why?
· Were there any ethnic, cultural, or regional influences in their diet?
· Do they have any nutritional related chronic disease(s)?
· What, if anything, are they doing to help the problem?
II. Take a diet history/24 hour recall (do during interview).
a. Analyze diet; identify key nutrient deficiencies in diet.
b. Include the 24 hour recall & Analysis as Appendix A of your paper.
III. Take anthropometric data & figure requirements
a. Get height & weight
b. Figure kcal & protein requirements
i. Determine if they are meeting needs using data from II.
IV. Give them an educational piece of material on the key nutrient deficiencies of elder adults. THIS IS DUE BY NOVEMBER 17th and worth 15 points
a. Language they understand
b. Large font
c. Easy to read
d. Include what the nutrient is, why it’s important, & where to find it in foods.
Turn in a ~3 pages essay in response to the questions from I. Discuss what you found out regarding the adequacy of their diet in II & III in your paper as well. The cover of this assignment should be a brief demographic description of the person you select (gender, age, where they live, health disparities, etc). Pictures are welcome and encouraged.
Conditions and interventions
Angie stiegemeyer, MA,rD,LD, BSN,RN
Southeast Missouri State University
Nutrition and the Older Adult
Health-sense of well-being
Quality of Life-measure of life satisfaction
Medical Nutrition Therapy-treatment of nutritional aspects of disease
Topics Covered
Cardiovascular Disease (CVD)/Heart Disease
Stroke
Hypertention
Diabetes/DM
Osteoporosis
Constipation
Osteoarthritis
Alzheimer’s Disease
Underweight
Elder Abuse
End of Life Care
Nutrition for CVD
Decrease amount of fat
Reduce cholesterol intake
Increase fiber, F & V
Limit Sodium
Exercise
Maintain Healthy Weight
Reduce Stress
Smoking Cessation
Stroke
Reduced blood flow to brain
Etiology
Blocked arteries
Easily clotting blood cells
Effects
Deprive brain of oxygen-nerve cells die
Differing levels of paralysis
Stroke
Risk Factors
Hypertension, high chol., DM, smoking, family hx, obesity
S/S: FAST
F-Facial weakness
A-Arm & Leg Problems
S-Speech Problems
T-Time to call 911
Nutrition
Normalize blood pressure
Hypertension
Systolic 140mm Hg or higher AND/OR Diastolic 90 mm Hg or higher
Effects- excess tension on vessels & organs
Wears them out before normal aging process
Kidney damage
Risk Factors
Excess alcohol intake, high sat. fat intake, overweight & obesity, low calcium intake, smoking
Nutrition for Hypertension
DASH Diet
Weight management
Moderate alcohol intake
Limit sodium
Adequate calcium, po ...
This presentation is about aging and aging related changes in the body. Here we learn how yoga can be an effective lifestyle modification to age gracefully. Here I have discussed about various research based yogic and lifestyle procedures to manage old age related complications and diseases. I have discussed about sattvic diet, asana, pranayama, mudras, bandhas, meditation and how they will be helpful according to science.
An enzyme is a substance that acts as a catalyst in living organisms, regulating the rate at which chemical reactions proceed without itself being altered in the process. The biological processes that occur within all living organisms are chemical reactions, and most are regulated by enzymes
The aqueous humour is a transparent, watery fluid similar to plasma, but containing low protein concentrations. It is secreted from the ciliary epithelium, a structure supporting the lens
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. The cornea, with the anterior chamber and lens, refracts light, with the cornea accounting for approximately two-thirds of the eye's total optical power.
Lens is a transparent, biconvex, crystalline structure placed between iris and the vitreous in a saucer-shaped depression, the patellar fossa. The lens is a crystalline structure that is avascular and is devoid of nerves and connective tissue
It consists of three distinct part:
Lens capsule
Anterior lens epithelium, and
Lens substance or lens fibres
Small amounts of vitamins are required in the diet to promote growth, reproduction, and health. Vitamins A, D, E, and K are called the fat-soluble vitamins, because they are soluble in organic solvents and are absorbed and transported in a manner similar to that of fats.
Water soluble vitamins include Vitamin C and the vitamin B complex: thiamin (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), Vitamin B6, biotin (B7), folic acid (B9), Vitamin B12. Vitamin A in its Beta-Carotene form is also water-soluble.
The tear film is a complex mixture of substances secreted from multiple sources on the ocular surface, including the lacrimal gland, the accessory lacrimal glands, the meibomian glands, and the goblet cells.
A picornavirus is a virus belonging to the family Picornaviridae, a family of viruses in the order Picornavirales. Vertebrates, including humans, serve as natural hosts. Picornaviruses are nonenveloped viruses that represent a large family of small, cytoplasmic, plus-strand RNA viruses with a 30-nm icosahedral capsid.
Poxviruses are brick or oval-shaped viruses with large double-stranded DNA genomes. Poxviruses exist throughout the world and cause disease in humans and many other types of animals. Poxvirus infections typically result in the formation of lesions, skin nodules, or disseminated rash.
Leptospirosis is a bacterial disease that affects humans and animals. It is caused by bacteria of the genus Leptospira. In humans, it can cause a wide range of symptoms, some of which may be mistaken for other diseases. Some infected persons, however, may have no symptoms at all.
The human immunodeficiency virus (HIV) is a lentivirus (a subgroup of retrovirus) that causes HIV infection and over time acquired immunodeficiency syndrome (AIDS).
Treponema is a genus of spiral-shaped bacteria. The major treponeme species of human pathogens is Treponema pallidum, whose subspecies are responsible for diseases such as syphilis, bejel, and yaws.
Haemophilus is the name of a group of bacteria. There are several types of Haemophilus. They can cause different types of illnesses involving breathing, bones and joints, and the nervous system. One common type, Hib (Haemophilus influenzae type b), causes serious disease. It usually strikes children under 5 years old
Moraxella is a genus of Gram-negative bacteria in the Moraxellaceae family. It is named after the Swiss ophthalmologist Victor Morax. The organisms are short rods, coccobacilli, or as in the case of Moraxella catarrhalis, diplococci in morphology, with asaccharolytic, oxidase-positive, and catalase-positive properties
Pseudomonas is a type of bacteria that can cause infections. Pseudomonas is a common genus of bacteria, which can create infections in the body under certain circumstances. There are many different types of Pseudomonas bacteria
Neisseria gonorrhoeae is the obligate human pathogen that causes the sexually transmitted disease (STD) gonorrhea. This Gram-negative diplococci/gonococci does not infect other animals or experimental animals and does not survive freely in the environment. The gonococcal infection occurs in the upper or lower tract, pharynx, ophthalmic area, rectum, and bloodstream. During the 1980’s gonorrhea was also referred to as “the clap” when public awareness was quite minimal. This was one of the venereal diseases prostitutes hoped to contract since it resulted in infertility by pelvic inflammatory disease (PID). As documentation, diagnostic testing, and public awareness improved, there has been a decline in incidence reports, however, it is still considered a very common infectious disease.
Meningococci are a type of bacteria that cause serious infections. The most common infection is meningitis, which is an inflammation of the thin tissue that surrounds the brain and spinal cord. Meningococci can also cause other problems, including a serious bloodstream infection called sepsis. In its early stages, you may have flu-like symptoms and a stiff neck. But the disease can progress quickly and can be fatal. Early diagnosis and treatment are extremely important. Lab tests on your blood and cerebrospinal fluid can tell if you have it. Treatment is with antibiotics. Since the infection spreads from person to person, family members may also need to be treated.
A vaccine can prevent meningococcal infections.
Diphtheria is an infection caused by the bacterium Corynebacterium diphtheriae. Diphtheria causes a thick covering in the back of the throat. It can lead to difficulty breathing, heart failure, paralysis, and even death. CDC recommends vaccines for infants, children, teens and adults to prevent diphtheria. The presentation consists of basic concepts regarding the bacteria and its infection. It has explanation in detail about signs and symptoms of Diptheria
Contraindications, Adverse reactions and ocular nutritional supplementsArun Geetha Viswanathan
utritional supplements comprise a great deal of the products available over the counter in most pharmacies. Although most vitamin supplements are relatively harmless—except for the fat soluble ones A, D, E, and K—they are not the only supplements available to patients. Some of these other, non-vitamin supplements can actually be harmful to patients and often they have been proven to be ineffective. This doesn’t mean that patients will stop taking them though, which in turn leaves the potential for contraindications of nutritional supplements with prescription-based drugs wide open.
Every component of the eye is vulnerable to damage from ROI, particularly retina. There are several reasons for the vulnerability of the retina, including high concentrations of polyunsaturated fatty acid (PUFA), constant exposure to visible light, high consumption of oxygen, an abundance of photosensitisers in the neurosensory retina and the RPE, the process of phagocytosis by the RPE which is known to generate hydrogen peroxide.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
The ASGCT Annual Meeting was packed with exciting progress in the field advan...
Nutrition and ocular aging
1. Unit: V
Vitamin A, C and E deficiency
Nutrition and ocular aging
Contraindications Adverse reactions and ocular nutritional supplements
Attribution-NonCommercial-ShareAlike
4.0 International (CC BY-NC-SA 4.0)
2. Unit: V
Nutrition and ocular aging
Attribution-NonCommercial-ShareAlike
4.0 International (CC BY-NC-SA 4.0)
3. The Ageing Process
• Ageing is a gradual process that takes place over many decades
• Most theories of ageing relate to impaired DNA replication and loss of cell viability
and hence the viability of the body’s organs
• Ageing is often accompanied by socioeconomic changes that can have a great
impact on the nutritional needs and status of elderly individuals
• The incidence of disability increases with ageing, with over a third of the elderly
population limited by chronic conditions and unable to carry on normal daily living
activity
4. Characteristics of ageing
1. Increased mortality with increasing age after maturation
2. Change in the biochemical composition of tissues with increasing age
3. Progressive decrease in physiological capacity with increasing age
4. Reduced ability to respond adaptively to environmental stimuli with increasing age
5. Increased susceptibility to disease with increasing age
5. Common theories of ageing
1. Immunological breakdown
2. Reduction in cellular proliferation
3. Reduction in basal metabolic rate
4. Reduction in telomere length
5. Reduction in DNA repair activity
6. Free radical damage
7. Reduction in rate of protein synthesis and catabolism
6. Nutrition and The Ageing Process
• Some major biological changes seen amongst elderly people occur primarily as an
irreversible result of the ageing process.
• However, many of the health problems and physiological changes experienced by
older people, commonly attributed to the ageing process, are now recognised to be
linked to lifestyle or environmental factors
• Good nutrition and other lifestyle factors, such as being physically active and not
smoking, are essential to ensure that people have long, healthy and active lives,
continuing to live independently for as long as possible
7. Dietary restriction experiments with animal models
• Moderate energy restriction markedly extends the life span of experimental
animals, compared with control animals
• It is also known that dietary restriction decreases the incidence of several chronic
diseases such as glomerulonephritis, atherosclerosis and cancer
• The mechanism or mechanisms through which this prolongation of life occurs are
unclear
• Caloric restriction reduces metabolic rate and oxidative stress, improves insulin
sensitivity, and alters neuroendocrine and sympathetic nervous system function in
animals.
8. Malnutrition Prevalence In Older People
• Morley and Silver highlighted that malnutrition is common among nursing-home
residents, and that protein–energy undernutrition prevalence ranges from 17 to
65% in this setting.
• Neel suggested that approximately 50% of residents in care homes in the USA are
undernourished
• whilst Crogan et.al. found the rate in some homes to be as high as 85%
• UK National Diet and Nutrition Survey of people aged 65 years and older examined
453 older people from 155 care homes, and found that 15% of women and 16% of
men were malnourished, compared to figures of 6 and 3% respectively of those
living in the community independently
9. In the Survey in Europe on
Nutrition and the Elderly: A
Concerted Action (SENECA) study,
which sampled a cohort of
community-dwelling subjects born
between 1913 and 1918 in 12
European countries, a relatively
high risk of malnutrition was
found (47% for vitamin D, 23.3%
for vitamin B6, 2.7% for vitamin
B12 and 1.1% for vitamin E)
10. Factors Affecting Nutritional Status
• Elderly persons are more likely to be in marginal nutritional health and thus to be at
higher risk of frank nutritional deficiency in times of stress or health care problems
• Physical, social and emotional problems may interfere with appetite or affect the
ability to purchase, prepare or consume an adequate diet
• These factors include whether or not a person lives alone, how many daily meals
are eaten, who does the cooking and shopping and any physical impediments such
as problems in chewing and denture use, adequate income to purchase appropriate
foods, and alcohol and medication use
11. THE PHYSICAL EFFECTS OF AGEING
• In general, older people tend to lose bone and muscle and gain body fat.
• Loss of muscle, known as sarcopenia, can be significant in later years and its
consequences may be dramatic
• Loss of muscle mass reduces energy requirements and may also reduce mobility
• As people lose their ability to move and maintain balance, falls become more likely
• The limitations that accompany the loss of muscle and its strength would appear to
play a key role in the diminishing health that often accompanies ageing.
• Optimal nutrition and regular physical activity can help maintain muscle mass and
strength and minimise the changes in body composition associated with ageing.
Body composition
12. THE PHYSICAL EFFECTS OF AGEING
• Energy expenditure tends to decrease as people age
• The basal metabolic rate (BMR) of 70-yearolds is approximately 9–12% lower than
that of adults aged 18–30 years, mainly because of a reduction in lean body mass
• As people grow older, physical activity may decrease as they become increasingly
sedentary
• However, activity levels in the elderly do vary widely, ranging from the physically
active recently retired to the frail and chair-bound
Energy expenditure and physical activity
13. THE PHYSICAL EFFECTS OF AGEING
• Even in the eighth decade of life, activity levels of some people can equate to those
of younger and middle-aged people
• Reduced activity levels lead to accelerated loss of muscle (although sarcopenia does
occur regardless of activity levels), with the resultant declines in muscle strength
and mass leading to a reduced BMR.
• The degree of loss may be ameliorated by resistance training exercise, which can
increase muscle mass and strength even in individuals suffering from chronic
disease
Energy expenditure and physical activity
14. THE PHYSICAL EFFECTS OF AGEING
• Bone density is reduced with increasing age, and this process is more predominant
in women
• Up until about the age of 30, the rate of new bone formation exceeds that of bone
degradation
• Once peak bone mass is achieved at about this age this process is reversed, and
minerals and collagen matrix are removed from bone faster than new bone tissue is
added
• There are many factors that influence the rate of age-related bone loss, such as
immobility, thinness, cigarette smoking, alcohol intake, physical activity, obesity and
hormone replacement therapy use
Bone loss
15. THE PHYSICAL EFFECTS OF AGEING
• Studies of sensitivity in taste amongst older people show a gradual decline with age, and this is
likely to have an impact on food selection
• The loss of taste and/or smell is highly variable, and certain medical conditions and some drugs
may affect taste, smell and appetite, thus affecting food intake
• In addition to altered taste perception, a person’s enjoyment of eating may be impaired by
reduced salivary flow and a resulting dry mouth
• These do not usually arise as an inevitable consequence of ageing, but rather as a side-effect of
medication, or the presence or treatment of disease (e.g. with radiotherapy)
• Decreased thirst sensation may exacerbate the problem of a dry mouth, and can contribute
towards dehydration.
• A stroke can affect a person’s swallow reflex, making eating and drinking difficult
• Older adults are at risk of dehydration due to reduced fluid intake and increased fluid losses
Taste changes
16. THE PHYSICAL EFFECTS OF AGEING
• Mental impairment and dementia, as a result of chronic degenerative brain disease,
can have a severe impact on a person’s autonomy and independence
• Cognitive impairment is thought to be sensitive to vitamin and mineral status
Neurological and cognitive function
17. THE PHYSICAL EFFECTS OF AGEING
Immune function
• Considerable evidence indicates that ageing is associated with altered regulation of
the immune system, and this contributes to the increased incidence of infections
seen in older people, and to their prolonged recovery period post-illness
• Studies have shown that undernutrition contributes to the decline of the immune
response with ageing
• However, it is not yet clear whether this effect is due to protein–energy
undernutrition, micronutrient deficiency or deficiency of some other dietary
component
18. THE PHYSICAL EFFECTS OF AGEING
Dentition
• Poor dentition can have a major impact on the foods, and therefore nutrients, that
can be consumed
• The National Diet and Nutrition Survey of people aged 65 years and over in the UK
found that those who had their own teeth had better vitamin and mineral intakes
and better nutritional status than those who had lost most or all of their teeth
• Those with no or few natural teeth ate a more restricted range of foods, because of
their perceived inability to chew.
19. THE PHYSICAL EFFECTS OF AGEING
Digestive function
• It is thought that the digestive and absorptive efficiency of the gastrointestinal (GI)
tract declines with age
• The intestinal wall loses strength and elasticity with age, and GI hormone secretions
change
• All of these actions slow motility, and as a result constipation is much more
common in the elderly than in the young
• The most significant change in GI function with ageing is the reduction in gastric
acid output in older people who have atrophic gastritis
• Atrophy of the stomach mucosa becomes more common in old age and is estimated
to affect about 30% of those over 60 years
20. THE PHYSICAL EFFECTS OF AGEING
Digestive function
• Gastric acid, intrinsic factor and pepsin secretion are reduced, which impairs the
digestion and absorption of nutrients, most notably vitamin B12, but also biotin,
folate, calcium, iron and zinc
• Pancreatic enzyme secretion also appears to decline with age, impairing the
digestion of fat and protein when consumed in large amounts
• Sensitivity of the gallbladder to cholecystokinin (a hormone that influences the
release of bile from the gallbladder) may be reduced in older people and this may
also have adverse effects on fat digestion
21. THE PHYSICAL EFFECTS OF AGEING
Eyesight
• Deteriorating eyesight can make buying food more difficult, in terms of getting to
the supermarket (an inability to drive, for example), reading food labels and
counting money
• Failing eyesight can also affect a person’s ability to prepare food.
22. NUTRITIONAL NEEDS OF OLDER ADULTS
Energy and macronutrients
• Older adults often have reduced energy needs because of their reduced energy expenditure
• If energy intakes are lower, it becomes crucially important that the foods that are consumed are
micronutrient-dense so that other nutritional needs are still met.
• Foods with high nutrient density that are low in fat, such as lean meat, fish helpful in that they
provide the protein, vitamins and minerals the elderly need with relatively few calories
• Data on protein requirements of the elderly are limited, but the currently available evidence
suggests that, in healthy elderly people, a mean intake of 0.75–0.8 g protein/kg body weight per
day results in nitrogen balance.
• Recommendations for carbohydrate and fat are similar for healthy elderly people and for healthy
younger adults, but for elderly people with small appetites, fat may be substituted for starchy
carbohydrates to make up energy needs
23. NUTRITIONAL NEEDS OF OLDER ADULTS
Micronutrients
• Ageing affects requirements for certain micronutrients, but it is difficult to
distinguish changes in nutrient needs resulting from the ageing process alone from
those resulting from disorders prevalent in older people
• Low-to-inadequate dietary intake may account for much of the poor vitamin status
observed in the elderly.
24. NUTRITIONAL NEEDS OF OLDER ADULTS
Vitamins
• older people may have greater needs for vitamins B12, B6 and folate owing to the
prevalence of disorders that reduce absorption (e.g. atrophic gastritis)
• Elderly people may also have increased requirements for vitamin D, which is
necessary for the absorption of calcium and important for bone health
• Deficiency of vitamin D in older people is a significant risk factor for hip fractures
• the main source of vitamin D is from the action of sunlight on skin, but for older
people, particularly for those in residential or nursing homes, exposure to the sun
may be limited
25. NUTRITIONAL NEEDS OF OLDER ADULTS
Vitamins
• Older skin also has a reduced ability to synthesise the pre vitamin D3, and declining
kidney function may result in impaired synthesis of active metabolites of vitamin D
• Diet is a secondary source of vitamin D, as only a few foods such as oily fish, meat
and fortified margarines contain substantial amounts of vitamin D
• Oxidative stress is believed to be an important factor in ageing and many age-
associated degenerative diseases
• Dietary antioxidants are regarded as being important in modulating oxidative stress,
However, there are no special dietary reference values for vitamin C or vitamin E in
the elderly
26. NUTRITIONAL NEEDS OF OLDER ADULTS
Minerals
• The body’s requirements for iron are lowest in old age, as iron is not required for
growth and there is no menstrual blood loss
• However, factors associated with old age may increase the risk of iron deficiency
anaemia, and the consequences of this can be life-threatening
• Factors that may increase the risk of iron deficiency include chronic blood loss from
ulcers or other disease conditions, poor iron absorption due to reduced stomach
acid secretion or medicines like aspirin that can cause blood loss from the GI tract
• Older people should be encouraged to consume foods containing bioavailable haem
iron, such as red meat, liver and meat products
27. THEORIES OF AGEING
Evolutionary theories
• These theories basically argue that ageing results from a decline in the force of
natural selection.
• Evolutionary pressures select for a minimum successful life, which includes the
ability to reach reproductive age, procreate and care for offspring until they are
weaned.
28. THEORIES OF AGEING
Evolutionary theories
• Mutation accumulation
• Detrimental, late-acting mutations
that affect older age are not selected
against, and therefore may
accumulate within a population and
ultimately lead to pathology and
senescence.
• Disposable soma
• The somatic organism is effectively
maintainedonly for reproductive
success, after which it is disposable;
longevity has a cost and therefore the
balance of resources invested in
longevity versus reproductive fitness
determines the life span.
29. THEORIES OF AGEING
Evolutionary theories
• Antagonistic pleiotropy
• Genes that are beneficial at a younger age become deleterious at an older age.
An example is the p53 tumour suppressor gene which appears to require a fine
equilibrium in order for the organism to achieve a long life span. Too little p53
results in death from cancer whereas too much p53 leads to death by
accelerated ageing
30. THEORIES OF AGEING
Molecular theories
Gene regulation
• Ageing is caused by changes in the expression of genes regulating development and
ageing
Codon restriction
• Fidelity/accuracy of mRNA translation is impaired due to the inability to decode codons
in mRNA.
Error catastrophe
• This theory proposes that random errors in synthesis eventually occur in proteins that
synthesise DNA or other ‘template’ molecules, leading to rapid accumulation of error-
containing molecules that would be incompatible with normal function and life.
31. THEORIES OF AGEING
Molecular theories
Somatic mutation
Random damage to vital molecules accumulates to a sufficient level to result in the
physiological decline associated with ageing.
Dysdifferentiation
Gradual accumulation of random molecular damage impairs regulation of gene
expression.
32. THEORIES OF AGEING
Cellular theories
Cellular senescence – telomere theory
• Phenotypes of ageing are considered to be caused by an increase in the frequency of
senescent cells
• Senescence may result from cellular stress (cellular senescence) or telomere shortening
(replicative senescence)
• Telomeres are specialised structures composed of repeating DNA sequence, and are
located at the ends of each chromosome
• Cell division results in ever-shorter telomeres, altered telomere structure, and,
ultimately, replicative senescence
• In this context, environmental influences such as exposure to high levels of oxidative
stress, and thus damage, have been shown to accelerate telomere shortening
33. THEORIES OF AGEING
Cellular theories
Free-radical theory
• This theory postulates that the ageing process is the consequence of free-radical
reactions
• Free radicals are responsible for the progressive deterioration of biological systems
over time because of their unstable state
Wear and tear
• This involves accumulation of normal injury
Apoptosis
• Apoptosis is programmed cell death from genetic events or genome crisis
34. THEORIES OF AGEING
System-based theories
Neuroendocrine
• Functional decrements in neurons and their associated hormones that control
homeostasis may result in age-related physiological changes
Immunological
• Decline of immune function (decreased T-cell response) with ageing results in
decreased incidence of infectious diseases but increased incidence of
autoimmunity (e.g. increased serum antibodies)
Rate of living
• The rate of living assumes a fixed amount of metabolic potential for every living
organism (live fast, die young)
35. Anatomical And Physiological Age-related Changes In The Eye
Cornea
The changes which occur in the cornea can be divided into three main categories:
(1) changes in shape and optical properties
(2) corneal degeneration
(3) physical and biological changes
36. Changes in Cornea
• a shift from with-the-rule to against-the-rule astigmatism
• decreasing pressure from the lids as they become more relaxed with age
Changes in shape and optical properties
37. Changes in Cornea
• ageing influences changes in patterns of astigmatism differently in men and
women, with the corneas of older men flatter than those of older women
• Transparency is unaffected in the central cornea by physiological ageing
• The average corneal radius decreases with age, and the cornea becomes more
spherical, resulting in significantly more spherical aberration in middle-aged and
older corneas
• Image quality is degraded with age as a consequence of increased wave
aberrations
Changes in shape and optical properties
39. Changes in Cornea
• intramolecular and interfibrillar spacing in collagen increases with age, possibly
via increased protein glycation
• Also, the number of corneal endothelial cells decreases as they do not regenerate,
and neighbouring cells expand to fill the space, resulting in a departure from the
classical uniform six-sided endothelial cell appearance (polymorphism)
Changes in shape and optical
properties
41. Changes in Cornea
Changes in shape and optical properties
Galgauskas, S., juodkaite, grazina, & Tutkuviene, J. (2014). Age-related changes in central corneal thickness in normal eyes among
the adult Lithuanian population. Clinical Interventions in Aging, 1145. doi:10.2147/cia.s61790
42. Changes in Cornea
Cornea farinata
This innocuous condition is
characterised by the presence of
minute, usually flour-like deposits
in the deep corneal stroma that are
most prominent centrally.
Corneal degenerations
43. Changes in Cornea
Vogt’s limbal girdle
This common, innocuous, bilateral, asymptomatic, age-related finding is characterised
by narrow, crescenteric, white opacities of the peripheral cornea in the interpalpebral
zone along the nasal and temporal limbus. It is seen in all patients over the age of 80,
and in 50% of normal eyes of people between the ages of 40 and 60
Corneal degenerations
44. Changes in Cornea
Deep crocodile shagreen
This is usually asymptomatic, and
appears as bilateral, polygonal,
greyish-white opacities which can
occur either in the anterior two-thirds
of the stroma (anterior crocodile
shagreen) or more posteriorly
(posterior crocodile shagreen). These
are thought to be due to changes in
the collagen lamellae accompanied by
widely spaced collagen fibres.
Corneal degenerations
45. Changes in Cornea
Hassall–Henle bodies
These are defined as small
hyaline excrescences on the
posterior surface of
Descemet’s membrane at
the periphery of the cornea.
Corneal degenerations
46. Changes in Cornea
Arcus senilis
This is the most common peripheral corneal opacity.
It appears as bilateral grey, white or yellowish
circumferential deposits in the peripheral cornea.
The sharp peripheral edge is usually separated from
the limbus by a lucid area, and this clear zone may
occasionally undergo thinning. Its presence is due to
increased permeability of local blood vessels to
lipids, and is related to serum cholesterol level..
Corneal degenerations
47. Changes in Cornea
• Resistance to corneal infection is reduced with increasing age, as is the number of
phagocytically active cells following infection
• Other age-related features include:
1. failure to upregulate intercellular adhesion molecule-1 (ICAM-1) and reduced
inflammatory cell infiltration
2. a decline in high energy metabolism
3. increased tear contact time
4. increased epithelial permeability to fluorescein
5. reduced corneal sensitivity
Physical and biological changes
48. Changes in lens
• Lens growth in adults cause an increase in the dioptric power of the lens, which is
attenuated by a compensatory decrease in refractive index of the lens with time
• Increased absorption and scatter of optical radiation with age cause the lens to
become yellow and fluorescent, contrasting sharply with the young human lens
• a decrease in low-contrast acuity
49. Changes in Optic nerve
• Ageing is associated with an increase in mean diameter of the optic nerve
• The mean number of nerve fibres of large diameter decreases with increasing age
• increased elastin and decreased fibronectin; a decreased lipid content; and
decreased total sulphinated glycosaminoglycans