Attention%20Deficit%20Hyperactivity%20Disorder

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Attention Deficit Hyperactivity Disorder

• James H. Johnson, Ph.D., ABPP
• University of Florida

2
ADHD Nature of the Problem

• ADHD is a neurodevelopmental disorder of
  childhood that is characterized by
  developmentally inappropriate levels of
• Hyperactivity,
• Impulsivity,
• Inattention.

3
ADHD How Common is it?

• Prevalence is estimated at 3 to 9 per cent of the
  elementary school population.
• ADHD occurs more often in males than females,
  with the sex ratio being about 4 to 1 to 9 to 1.
• It is one of the most common disorders of
  childhood
• Accounts for a large number of referrals to
  pediatricians, family physicians and child mental
  health professionals.

4
ADHD Not a New Problem

• Characteristics of this disorder have been
  recognized for at least a century.
• The disorder has been referred to by a variety of
  labels
• Minimal Brain Dysfunction (MBD)
• Hyperkinetic Reaction of Childhood
• Attention Deficit Disorder (ADD)
• Attention Deficit Hyperactivity Disorder (ADHD)

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ADHD Evolution of the Disorder

• Still (1902) ADHD Case study
• Encephalitis epidemic of 1917
• Frontal lobe ablation studies with primates
  (1930s)
• Strauss work on Minimal Brain Dysfunction
  (1940's -1950's)
• Beginnings of child psychopharmacology Using
  Amphetamines for treatment 1930-1940.
• MBD becomes Hyperkinetic Disorder (the 1960s)

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ADHD Evolution of the Disorder (cont.)

• Hyperkinesis becomes ADD The decade of the 70s
• Focus on Dietary Factors Feingold and the
  1970s
• Studies of psychophysiological responses of
  hyperactive children the 1970s
• Development of objective diagnostic criteria DSM
  III
• Recognition of Attention Deficit Disorder The
  early 80s

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ADHD Evolution of the Disorder (cont.)

• The decade of the 80s DSM III DSM III-R
  stimulates ADHD research and the development of
  new assessment methods new treatment methods -
  increased focus on biological factors.
• The 1990s - Present Neuroimaging, genetics and
  and a reevaluation of DSM.

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ADHD Core Features

• As noted earlier, ADHD is a disorder
  characterized by developmentally inappropriate
  levels of
• Hyperactivity,
• Impulsivity,
• Inattention.

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DSM IV Symptoms of Hyperactivity

• Often fidgets with hands or feet, squirms in
  seat.
• Often leaves seat in classroom or in other
  situations in which remaining seated is expected
• Often runs about or climbs excessively in
  situations in which it is inappropriate.
• Often has difficulty playing or engaging in
  leisure activities quietly.

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Hyperactive Symptoms

• Is often "on the go" or often acts as if "driven
  by a motor.
• Often talks excessively when inappropriate to the
  situation
• A combined total of 6 or more of
  hyperactivity/impulsivity criteria are required
  for diagnosis.

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What do we Know about Hyperactivity?

• Children with ADHD are more active, restless, and
  fidgety than normal children during the day and
  during sleep.
• There are different types of hyperactivity.
• Gross Motor Activity
• Restless/Squirmy
• Occasionally see verbal hyperactivity
• Hyperactivity often varies according to
  situation.
• Degree of hyperactivity may vary with age.

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Symptoms of Impulsivity

• Often blurts out answers before questions have
  been completed.
• Often has difficulty awaiting turn.
• Often interrupts or intrudes on others.
• Six symptoms of hyperactivity and impulsivity
  are required for diagnosis.

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Symptoms of Inattention

• Often fails to give close attention to details or
  makes careless mistakes.
• Often has difficulties sustaining attention in
  tasks or play activities.
• Often does not seem to listen when spoken to
  directly.
• Often does not follow through on instructions and
  fails to finish homework, chores, or duties in
  the workplace

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Symptoms of Inattention

• Often has difficulty organizing tasks and
  activities
• Often avoids, dislikes, or is reluctant to engage
  in tasks that require sustained mental effort.
• Often loses things necessary for tasks or
  activities
• Is often easily distracted by extraneous stimuli.
• Is often forgetful in daily activities
• (6 or more necessary for diagnosis)

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What Do We Know About ADHD Attention Problems?

• ADHD "attentional" problems may be most obvious
  on specific types of attentional tasks.
• Children with ADHD seem to have their greatest
  difficulties with sustaining their attention in
  responding to tasks - in being vigilant.
• Attention problems are usually seen most clearly
  in situations requiring the child to attend over
  time to dull, boring, and repetitive tasks.

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Situational Variations in Symptoms

• ADHD symptoms show significant variation across
  situations.
• Children with ADHD do not display symptoms in all
  situations
• The absence of symptoms in some situations does
  not mean that the child does not have ADHD.

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Situations That Increase ADHD Symptoms

• When the demands of the situation are to be good,
  to be still, and to be quiet.
• The greater the demands, the more problematic the
  behavior of the child will likely become.
• An exception might be in situations where the
  child is being continuously rewarded for
  complying with demands.
• In familiar situations where novelty and task
  stimulation are low.

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Other Situations That Increase Symptoms

• Situations where there are low rates of intrinsic
  or external reinforcement.
• When the child is fatigued.
• Studies, monitoring 24 hour activity levels have
  suggested that the hours of 1 5 seem to be peak
  times for increased activity in children with
  ADHD.

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Overview of Diagnostic Criteria

• Symptom Criteria - Core Symptoms of Hyperactivity
  Impulsivity and/or Inattention (Six or More
  Symptoms of either category).
• Duration Criterion - Symptoms have Persisted for
  at Least 6 Months.
• Developmental Criterion - Symptoms are
  Inconsistent with Developmental Level.
• Impairment Criterion - Clear Evidence of
  Clinically Significant Impairment in Social,
  Academic, or Occupational Functioning

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Overview of Criteria (cont.)

• Age Criterion - Some Symptoms that Cause
  Impairment Were Present Before Age 7.
• Situation Criterion - Some Impairment from
  Symptoms is Present in Two or More Settings.
• NOTE. The failure to attend to full range of
  symptoms is not uncommon
• Presence of hyperactivity, impulsivity, and
  inattention is not necessarily to be equated with
  ADHD.

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Types of ADHD

• Combined Type
• Symptoms of hyperactivity, impulsivity and
  inattention.
• Hyperactive/Impulsive
• Symptoms of hyperactivity and impulsivity.
• Predominately Inattentive
• Symptoms of inattention.

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ADHD Mimicry

• Sensory Impairments
• Medication side effects
• Phenobarbital
• Dilantin
• Some Asthma Medications
• Seizure Disorder
• RTH (Resistance to Thyroid Hormone)
• PTSD
• Bipolar Disorder
• Anxiety Disorders
• Depressive Disorders

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Comorbid Conditions

• What are comorbid conditions?
• Controversy over use of the term.
• Why is it essential to consider the possibility
  of comorbid conditions in assessing children with
  ADHD?
• Importance of distinguishing between comorbid
  conditions and mimicry.
• What is the frequency of comorbidities in
  children with ADHD?

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Comorbid Conditions

• Learning Disabilities - 19 to 26
• Oppositional Defiant Disorder - 40 Conduct
  Disorder - 25 children 45-50 Adolescents.
• Anxiety Disorders - 30
• Depressive Disorder - 10 - 30
• Bipolar Disorder up to 20.
• Tics and Tourettes Disorder 7 of children
  with ADHD have a tic disorder.
• 40 to 50 of those with Tourettes disorder have
  ADHD

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Developmental Issues

• There are factors in infancy, such as difficult
  temperament, that appear to be early precursors
  of ADHD.
• Initial development of ADHD is most often during
  the preschool years.
• While there is often a decline in the level of
  hyperactivity and some improvement in attention
  and impulse control in adolescence, perhaps 80
  continue to be impaired by their symptoms and
  meet current diagnostic criteria.
• A significant number of children with ADHD
  (probably over 50) continue to display problems
  into the adult years.

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Prognosis of ADHD

• Outcome of ADHD in adolescents is highlighted by
  the results of a study by Barkley, Fischer, et
  al, (1990).
• This study followed a large sample of ADHD (158)
  and normal children (81) prospectively for 8
  years after diagnosis.
• 123 hyperactive children and 66 normals were
  located, interviewed and complete questionnaires.
• In the hyperactive group 12 (9.7) were female
  and 111 were male. In the normal group 4 of the
  subjects were female and 62 were male.
•  

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Prognosis In Adolescence

• The vast majority of the hyperactive subjects
  (71.5) met DSM III-R criteria for ADHD at follow
  up.
• More than 59 met criteria for Oppositional
  Defiant Disorder as compared to 11 of the
  controls.
•  Approximately 43 of the hyperactive group
  could be diagnosed as CD as compared to 1.6 of
  the control group.

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Prognosis Continued

• Hyperactive subjects were more likely to have had
  an auto accident, to have had more automobile
  accidents, to have had more bodily injuries in
  accidents, and to be at fault for accidents more
  often than did controls.
• Adolescents in the hyperactive group were also
  more likely to have received traffic citations,
  especially for speeding

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Prognosis Continued

• Cigarette and alcohol use were the only
  categories of substance use that differentiated
  hyperactives and normals.
• When the the hyperactive sample was separated
  into groups (purely ADHD and ADHD CD) purely
  ADHD subjects showed no greater use of
  cigarettes, alcohol, or marijuana than did normal
  controls.
• Mixed hyperactive/Conduct disordered children
  displayed two to five times the rate of substance
  use as did pure hyperactives or normals.

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Prognosis Continued

• Three times as many hyperactives had failed a
  grade (29.3 versus 10), had been suspended
  (46.3 versus 15.2) or had been expelled (10.6
  versus 1.5).
• Results indicated that hyperactivity alone
  increases the risk of suspension (30.6 vs
  15.2), and dropping out
• (4.8 vs 0 ) as compared to controls
• However, the added diagnosis of CD greatly
  increases the risk (67 suspended, 13 dropped
  out).
• The presence of CD accounted almost entirely for
  the gt risk of expulsion within the hyperactive
  group

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Prognosis In Adulthood

• As many as 67 of children diagnosed with ADHD
  will display symptoms in adulthood serious enough
  to interfere with academic, vocational or social
  functioning.
• There are indications that the type of ADHD that
  persists into adulthood is more highly genetic
  than the type that remits in childhood.
• ADHD in adults is sometimes considered a hidden
  disorder as symptoms are often obscured by other
  problems.
• Prevalence is thought to be 2 4 with sex ratio
  of 2 1 or lower).

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Risk Factors

• Maternal cigarette use
• Maternal alcohol use
• Unusually long or short labor
• Forceps delivery
• Toxemia
• Meconium staining
• Birth during the month of September.
• Minor physical anomalies

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Etiology - Genetics

• Between 10 and 35 per-cent of the immediate
  family members of children with ADHD also display
  this disorder.
•  Risk for siblings of children with disorder is
  approximately 32
• If a parent has ADHD the risk to offspring is on
  the order of 50
• Twin studies suggest concordance rates for
  monozygotic twins is around 80 with concordance
  rates of approximately 30 for dizygotic twins.
• Overall, twin studies suggest an average
  heritability of .80

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Etiology Molecular Genetics

• Molecular genetics has begun to identify specific
  genes related to ADHD.
• A dopamine type 2 gene has been found to be
  related to ADHD as well as Tourettes and
  alcoholism.
• More recently a "dopamine transporter gene" and a
  dopamine repeater genehave been identified.
• This gene, found to be related to ADHD in
  multiple studies, seems to be related to
  post-synaptic sensitivity in the frontal and
  prefrontal cortical regions and to be associated
  with executive functions.

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Genetic Contributions (cont.)

• With developments in molecular genetics occurring
  at an increasingly rapid rate (due to the Human
  Genome Project), in the near future, we may have
  genetic tests that can provide early screening
  for ADHD and possibly associated comorbidities.
• Genetic factors are clearly strongly implicated
  in the development of this disorder.
• Hereditary is one of the most well supported
  etiological factors in the development of ADHD

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Etiology Neurological Insult

• Multiple factors that can result in brain damage
  are associated with ADHD.
• For example, anoxia, is associated with increased
  frequencies of hyperactivity and attentional
  problems.
• ADHD occurs more often in children with seizure
  disorders, who are presumed to have neurological
  involvement
• As was noted earlier, diseases such as
  encephalitis can also result in symptoms of ADHD
  as can various types of infections.

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Etiology Brain Damage

• These findings suggest that neurological insult
  can result in an increased probability of
  developing ADHD.
• However, most children with ADHD do not have a
  significant history of brain injury.
• Indeed, such injuries are unlikely to account for
  ADHD in most children.
• In fact probably 95 of hyperactive children show
  no evidence of documentable neurological
  impairment.
• This does not mean, however, that neurological
  factors are not involved.

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Neuropsychological Test Findings

• Results from research involving
  neuropsychological testing has often suggested
  that children with ADHD have problems
• in inhibiting behavioral responses,
• with working memory,
• with planning and organization,
• with verbal fluency,
• with perserveration,
• In motor sequencing,
• with other frontal lobe functions.

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Research with Neuropsychological Testing (Cont.)

• Not only do children with ADHD show executive
  functioning deficits but siblings of ADHD
  children who do not have ADHD, have milder yet
  significant impairments of the same type.
• This suggests a possible genetic risk for
  executive function deficits in families.

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Cerebral Blood Flow

• Studies of cerebral blood flow in ADHD and normal
  children have consistently shown decreased blood
  flow to the prefrontal regions and pathways
  connecting these regions to the limbic system via
  the striatum and specifically its anterior region
  (the Caudate Nucleus)
• Studies using PET scans to assess cerebral
  glucose metabolism in the frontal regions have
  found diminished metabolism in, adults and
  adolescent females with ADHD.

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Cerebral Blood Flow Continued

• Significant correlation's between diminished
  metabolic activity in the left anterior frontal
  region and severity of symptoms in adolescents
  with ADHD have also been demonstrated
• This demonstration of a relationship between
  decreased metabolic activity of certain brain
  regions and severity of ADHD symptoms is crucial
  to documenting the importance of the link between
  brain activation and behaviors associated with
  ADHD

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Frontal Lobes
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Basal Ganglia
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Striatal Network
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MRI Studies

• Early studies found differences in the Corpus
  Callosum, with this structure being smaller in
  children with ADHD. Not always replicated.
• Other MRI studies have found children with ADHD
  to have a smaller left caudate nucleus than did
  normal children. These findings are interesting
  in light of the results of earlier blood flow
  studies suggesting lower levels of activation in
  this specific area in children with ADHD.

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MRI Continued

• Several more recent MRI studies, with larger
  samples, have replicated these early results by
  finding that ADHD children had significantly
  smaller anterior right frontal regions, a smaller
  caudate nucleus, and smaller golbus pallidus
  regions that normals.
• Research has also found decreased cerebellar
  volume in ADHD children.
• Work in this area suggests that abnormalities in
  the development of the frontal-striatal regions
  may well underlie the development of ADHD.

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Neurotransmitter Deficiencies

• The possibility of a neurotransmitter dysfunction
  in children with ADHD has been suggested for many
  years.
• This notion seemed to originate from observations
  of the response of children with ADHD to
  different type of stimulant drugs.
• The fact that stimulant drugs have an impact on
  ADHD and that they increase dopamine has
  contributed to the neurotransmitter dysfunction
  hypothesis.

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Neurotransmitter Deficiencies

• There is more direct evidence of neurotransmitter
  deficiencies from studies of cerebral spinal
  fluid in ADHD and normal children which suggests
  decreased dopamine levels in ADHD children
• There is also some evidence of a deficiency in
  the availability of norepinephrine in children
  with ADHD.
• This is of interest given that a very new
  non-stimulant ADHD medication, Straterra, is
  thought to act on norepinephrine levels.

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Etiology Psychosocial Factors

• There is little evidence for the role of
  psychosocial factors in the development of ADHD,
  although factors such as parent-child conflict
  may exacerbate problems in a child with ADHD.
• Psychosocial factors may also contribute to the
  development of certain comorbid disorders that
  may complicate the clinical picture.

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Etiology Overview

• In reviewing the literature on the etiology of
  ADHD, Barkley suggests
• It should be evident from the researchthat
  neurological and genetic factors make a
  substantial contribution to symptoms of ADHD and
  the occurrence of this disorder.
• A variety of genetic and neurological etiologies
  (e.g., pregnancy and birth complications,
  acquired brain damage, toxins, infections, and
  genetic effects) can give rise to the disorder
  through some disturbance in a final common
  pathway in the nervous system.

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Overview Continued

• That final common pathway appears to be the
  integrity of the prefrontal cortical-striatal
  network.
• It now appears that hereditary factors play the
  largest role in the occurrence of ADHD symptoms
  in children.
• It may be that what is transmitted genetically is
  a tendency toward a smaller and less active
  prefrontal-striatal network.

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Overview Continued

• The condition can also be caused or exacerbated
  by pregnancy complications, exposure to toxins,
  or neurological disease
• Social factors alone cannot be supported as
  causal in this disorder, but such factors may
  exacerbate the condition, contribute to its
  persistence, and more likely, contribute to the
  forms of comorbid disorders associated with ADHD.
  
• Cases of ADHD can arise without genetic
  predisposition if the child is exposed to a
  significant disruption or neurological injury to
  this final common neurological pathway, but this
  would seem to account for only a small minority
  of ADHD children.

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Treatment of ADHD

• Stimulant Medications
• Other Medications
• Psychosocial Treatments
• Educational Accommodations

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Commonly Used Stimulant Medications

• Ritalin
• Dexadrine
• Adderall
• Concerta
• Between 70 and 80 of children with ADHD respond
  positively to stimulant drugs.
• Stimulant drugs represent an empirically
  supported treatment for core symptoms of ADHD.

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Side Effects of Stimulants

• Common side effects can include loss of
  appetite, weight loss, sleeping problems,
  irritability,
• restlessness, stomachache, headache, rapid heart
  rate, elevated blood pressure, sudden
  deterioration of behavior
• symptoms of depression with sadness, crying, and
  withdrawn behavior.
• intensification of tics (muscle twitches of the
  face and other parts of the body), possible
  Tourettes and growth suppression.

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Side Effects (Cont.)

• While side effects are always a possibility they
  are often
• Transient in nature
• The result of inappropriate medication levels
• If one medication results in side effects,
  another might be used without side effects.
• Sometimes other medications are used to minimize
  side effects.
• Good clinical judgment by the clinician may help
  to minimize side effects.

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Some Examples of NonStimulant Drugs in ADHD
Treatment

• Non Stimulant ADHD Medication
• Straterra - a norepinephrine reuptake inhibitor-
  selectively blocks the reuptake of
  norepinephrine, which increases its availability
• Other Non Stimulant Drugs
• Anti-depressants (e.g., Tofranil, Wellbutrin)
• Anti-hypertensives (Clonidine)

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Psychosocial Treatments

• Parent Training
• Social Skills Training
• Cognitive Behavioral Treatments.
• Psychotherapy for comorbid conditions

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Educational Interventions

• Special Education Services for existing learning
  problems.
• Classroom accommodations.
• Classroom behavior modification programs.

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ADHD Treatment Concluding Comments

• In treating ADHD it is essential to treat the
  full range of difficulties that impact on child
  and family functioning.
• Treatment of ADDH will often need to be
  multimodal in nature.
• Findings from the Multimodal Treatment Study
  suggest that
• Stimulant medication is effective in reducing
  core symptoms
• Psychosocial treatments are of value in
  addressing associated comorbidities.

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Thats All Folks!