Sarita due Sunday 12 September 2021
2500 words ± 10%
You will be marked against the criteria in the marking rubric for Case analysis.
Theme 5 Stress response in health and illness and theme 6 Immunology concepts
Weighting: 50%
referenced using APA style. •
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Microsoft WORD compatible format,.
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Based on E.3.3 ACN Marking Rubric –
UNDERSTANDING &; KNOWLEDGE
The student demonstrates a sound knowledge of the questions asked
Maximum score35
RESEARCH AND EVIDENCE
The student is able to integrate research and evidence based guidelines in a scholarly way
Maximum score25
ANALYSIS AND CRITICAL THINKING
The student demonstrates evidence of critical thinking in their answer
Maximum score25
WRITING The student writing is consistent with the ACN guidelines
Maximum score5
REFERENCING The student demonstrates knowledge of referencing according to the ACN guidelines
Maximum score10
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Case study: Sarita
Sarita is a 22-year-old overseas student who has been living in Australia for 18 months. She has been very fit, participating in many athletic events since childhood. Except for glandular fever as a teenager, Sarita has an unremarkable medical history. Over the past weeks she has experienced significant lethargy, anorexia, general aches and pains and non-specific bruising. She was reviewed by her GP who ordered blood tests and prescribed analgesics and anti-inflammatory medications. As her symptoms were not improving, Sarita was admitted yesterday for further investigations in view of an abnormal blood count.
Clinical assessment reveals:
HR 95 beats/minute
BP 100/60 mmHg
RR 18 breaths/minute
Temperature 38.2ºC
SpO2 92%
Blood pathology Suggested normal range
WBC 40 000 (4800–10 800 cells/μl [mm3] of blood)
Hb 85 g/L
Platelets 12 000 (150 000–400 000 cells/μl [mm3] of blood)
Sarita has been given the diagnosis of acute lymphocytic leukaemia and is awaiting further results and a management plan. Today she is anxious and has developed nose bleeds, a cough and a fever 38.2ºC. She is also suffering from an upper respiratory tract infection. Her mother has arrived from from India to be with her.
Management includes:
IV Fluids
3 units of packed cells
Ibuprofen
Panadeine FORTE®
CXR
The purpose of this assessment is to demonstrate your knowledge and understanding of complex pathophysiology related to a young person presenting with a significant immune disorder. This case analysis will enable you to explore the concepts of immune dysfunction, stress response, pain pathways and the associated clinical signs and symptoms. Sarita’s presentation is in the case studies folder and will be used to guide your discussion. Please complete all three parts.
Part A (750 words)
Physical examination shows that Sarita has pain and tenderness consistent with enlarged spleen. She also states that she is experiencing right lateral chest pain; exacerbated on inspiration. Panadeine forte and Ibuprofen were prescribed.
• Explain the types of pain Sarita is experiencing: outlining the pain pathways and the associated neurotransmitters.
• Discuss the positive and negative consequences of her prescribed analgesics on her clinical status. What impact will these medications have on her existing comorbidities, such as infection and bleeding.
B (750 words)
As a result of her hospitalisation and symptoms, Sarita is experiencing physical and psychological stress or the “alarm stage” of stress response.
• Analyse the effects of the alarm and resistance stages on Sarita’s immune and cardiovascular systems
• Explain how prolonged stress response could lead to neuro-endocrine exhaustion phase and irreversible systemic dysfunction such overwhelming sepsis.
Part C (1000 words)
Sarita’s diagnosis of leukaemia, the presence of infection as well her clinical findings show that the disease is advanced and potentially life threatening.
• Discuss the immune aspects and cellular changes associated with Sarita’s leukaemia
• Outline Sarita’s risk of bleeding and potential sites of haemorrhage (e.g. mucous membranes) that need to be assessed if her heart rate continues to rise
• Explain how intravascular fluids and pack cells will stabilise Sarita and prevent further deterioration in her condition. What parameters will need continued monitoring
Resources
As we have seen in previous themes, homeostasis is maintained through various feedback mechanisms. Understanding the physiology that supports homeostasis, we are better able to interpret the complex array of body’s responses to stress and illness related to homeostatic imbalance.
Loss of homeostasis impacts most body systems and is mediated via the autonomic nervous system. In particular, stress response is generated through the activity of the parasympathetic and the sympathetic nervous systems
Parasympathetic nervous system – we look at the components of the parasympathetic nervous system, the impact of cholinergic and anticholinergic medications on neurotransmission and implications for the compromised patient.
Sympathetic nervous system – we examine the role of the sympathetic nervous system in the stress response, and the implications of adrenergic and noradrenergic drugs on neurotransmission and the stress response.
Pain as a stressor – this explores the concept of pain, types of pain and physiological pathways of pain in relation to the stress response.
Content in the theme will explore:
disruption to homeostatic control
stress response and the ramifications on clinical assessment findings
actions and impact of commonly used drugs on patients experiencing the stress response
physiological impact of cholinergic and noradrenergic drugs
types of pain and the relationships between chronic and acute pain and the stress response
clinical assessment findings and predict changes in relation to the patient’s response to stress. Loss of homeostasis
Maintenance of homeostatic equilibrium requires the communication pathways between body systems to function smoothly. The nervous and endocrine systems utilise neural electrical impulses or bloodborne hormones as information carriers to enable them to work together. Homeostasis can be disrupted by pathogens, diseases and toxins. Nervous system generally responds rapidly to counteract the disrupting elements. The endocrine system is slower to act and can have more lasting consequences.
Examples of body functions under constant equilibrium are PB, blood pH, temperature, ventilation etc. All body components; from cells to body organs contribute in some aspect of homeostasis and the preservation of normal body functions. For example; high performance athletes push their bodies to the limit to change their cellular and organ function. They can derive significant physical benefits from intensive training. However, over-training can overwhelm the body’s homeostatic processes, resulting in injury and health breakdown. (Tortora & Derrickson 2019, p. 11)
Our innate resistance to stress and the body’s healing powers can be disrupted by many factors such as: genetic makeup, the environment, our behaviour and even our psychological disposition. Our internal environment is under constant challenge to avoid disorders and restore health if diseases do occur. (Tortora & Derrickson 2019, p. 17)
heme 5 Learning guide – Topics 1-2
Pathogens and body temperature response
The control of body temperature is a good example of homeostatic control. Many patients in your care will have experienced alteration in thermoregulation. Both hypothermia and hyperthermia are examples of altered homeostasis. High temperatures can be classed as either a fever or as hyperthermia.
Fever (pyrexia) assists in the body’s defence against invading organisms. There are many reasons for the development of a fever. Fever may be due to dehydration, infection, cancer, transfusion reaction, drug reaction or environmental factors to name but a few causes. Fever caused by a pyrogen (e.g. infection) changes the hypothalamic set-point for body temperature regulation.
Hyperthermia is typically seen in the context of head injury or other intracranial pathology, and may be caused by direct pressure on the hypothalamus. Hyperthermia in brain-injured patients must be controlled because it increases the metabolic rate of all cells including brain cells. Nicholson (2019) explains that “oxygen consumption rises approximately 5-7% for every 1°C rise in temperature. A rise from 37°C to 40.5°C results in a 35% increase in oxygen consumption”. There is therefore a potential for brain injury as oxygen supply may not meet oxygen demand.
Key point
Fever and hyperthermia both lead to increases in metabolic rate and oxygen consumption. Treatment for either will depend on understanding the underlying cause
When nursing immunocompromised patients, it is important to consider how their ability to mount a fever is affected. Such patients may not be able to mount a fever, but it doesn’t necessarily mean that they are free of infection. So it is important not to rely on temperature alone in determining whether a patient has an infection. Conversely, immunocompromised patients may sometimes have a fever in the absence of infection.
The following readings provide a good overview of the mechanisms and management of body temperature regulation.
Prescribed text reading
Marieb, EN & Hoehn, K c2018, Human anatomy and physiology, 11th edn, Global edn, Pearson Education, Harlow, Essex
Chapter 24: Nutrition, metabolism and energy balance.
Read ‘Section 24.11: The hypothalamus acts as the body’s thermostat’ (pp. 995-1001).
Chapter 21: The immune system: Innate and adaptive body defenses.
Read ‘Fever’ on page 821-822.
heme 5 Learning guide – Topics 1-2
Disease changed energy needs
Blood glucose levels are maintained primarily by glucagon and insulin, two of the hormones secreted by the pancreas. When blood glucose levels are not maintained between the normal range of 3.5 to 7.0 mmol/L (non-fasting) there are serious consequences. Hypoglycaemia can cause agitation and disorientation, convulsion and in severe cases unconsciousness. Hyperglycaemia causes fluid shifts and an osmotic diuresis which results in alteration in fluid and electrolyte balance. Diabetes mellitus is the most common disorder that alters blood glucose homeostasis. The three cardinal signs of diabetes mellitus are polyuria, polydipsia and polyphagia.
As you read the next part of your text, note the effects of glucagon and insulin on blood glucose control. Pay particular attention to the section on diabetes mellitus especially figure 16.18 on page 664. Ketoacidosis affects acid-base metabolism and hyperglycaemia will affect water and electrolyte homeostasis.
Endoplasmic Reticulum Stress in Metabolic Disorders – can be found in a Resources folder on the front page – Theme 5 section
Key point
The three cardinal signs of diabetes mellitus are polyuria, polydipsia and polyphagia.
Prescribed text reading
Marieb, EN & Hoehn, K c2018, Human anatomy and physiology, 11th edn, Global edn, Pearson Education, Harlow, Essex
Chapter 16: The endocrine system.
Read ‘Section 16.11: The pancreas, gonads, and most other organs secrete hormones’ pp. 662-664. heme 5 Learning guide – Topics 1-2
Disease changed energy needs
Optional Activity 5.1: Discussion forum – Fever
Understanding physiological benefits of fever helps us decided if and when we should intervene to decrease pyrexia.
Fever is a protective mechanism, but what is the physiology behind the changes in our thermostat?
Do these vary across the life span and what implication does this have for patient care related to different age groups? Toxins and loss of homestasis
Many toxins can invade the body and cause damage to cells and organs. Some of the prominent and well documented damaging toxins are those associated with tobacco and cigarette smoking. click on the links for more info.
Tobacco – you may wish to do some independent research on how tobacco affects cellular, organ and systemic function
Tobacco smoking in the Australian population
These two links will provide you with a lot of information on how tobacco smoke disrupts homeostasis and contributes to diseases and chronic poor health
opic 2 – Stress response
What is the stress response?
A stressor is an event or experience which will impact on the state of homeostasis; it may be perceived or real, psychological or physiological, acute or chronic. We are all exposed to stressors every day such as changes in external temperature, insufficient sleep, work pressures and anxiety about relationships or finances to name but a few. People who have experienced a number of more potent stressors such as pain, infection, blood loss, hypoxia, fear and anxiety, and sleep deprivation will develop health problems immediately or over time. Though we all experience stress, it is important to be aware that the stressors experienced by patients in our care tend to be much more serious when left unchecked and can negatively affect their health outcomes.
Stress has significant consequences for homeostasis and health. While the stress response is essential in maintaining homeostasis, it can have negative consequences on all body systems when allowed to continue out of balance. Homeostatic mechanisms attempt to counteract the effects of stress and return the body’s internal environment to normal.
The body’s response to stress is also known as the ‘flight-or-fight’ response. It involves both neural and endocrine responses that make heart rate, blood pressure and respiratory rate increase. The neural response is activated by the sympathetic nervous system (SNS), and it prepares our body for immediate physical activity. The endocrine response is under hormonal control that can respond to and sustained and prolonged stressors. (Tortora & Derrickson 2019, p. 11)
Patients in your care will experience many stressors that will have physiological consequences. You must be able to recognise stressors, monitor their effects and plan interventions to alleviate the stress and assist the body in restoring homeostasis. What is the stress response? (cont…)
Key characteristics of the stress response are:
It is coordinated by neurons in the hypothalamus, locus coeruleus, noradrenergic cell groups in the medulla and pons and the adrenal medulla.
A significant chemical mediator in the stress response is Corticotrophin releasing factor (CRF)
‘The impact of the stress response in critical illness is complicated by the presence of co-stressors such as tissue hypoxia and bacteraemia (Lusk & Lash, 2005, p. 26)
CRF, adrenocorticotrophic hormone (ACTH), glucocorticoids, mineralocorticoids and catecholamines are released in response to stress
Cortisol suppresses inflammatory and immune responses
Gender may influence the impact of the stress response
Patients experience significant stressors when they are ill
Prolonged stress response is a major factor contributing to chronic illness.
The following reading explores the stress response further. While the reading focuses their discussion on patients in the critical care environment, the information is extremely important for nurses across all care contexts. You will draw on the concepts covered in these readings throughout the rest of this subject.
Required reading
(Tortora & Derrickson 2019, p. 956-959) This reading is located in Theme 5 section – additional resources folder front page of this subject.
heme 5 Learning guide – Topics 1-2
Pain as a stressor
Proposed New Definition of Pain:
An aversive sensory and emotional experience typically caused by, or resembling that caused by, actual or potential tissue injury.
Proposed Accompanying Notes Section:
Pain is always a subjective experience that is influenced to varying degrees by biological, psychological, and social factors.
Pain and nociception are different phenomena: the experience of pain cannot be reduced to activity in sensory pathways.
Through their life experiences, individuals learn the concept of pain and its applications.
A person’s report of an experience as pain should be accepted as such and respected.
Although pain usually serves an adaptive role, it may have adverse effects on function and social and psychological well-being.
Verbal description is only one of several behaviors to express pain; inability to communicate does not negate the possibility that a human or a non-human animal experiences pain.
Etymology: Middle English, from Anglo-French peine, from Latin poena (penalty, punishment), in turn from Greek poinē (payment, penalty, recompense).
IASP’s Proposed New Definition of Pain Released for Comment Aug 7, 2019
Pain is a significant stressor that can trigger the physiological and psychological components of a stress response in the individual who is experiencing that pain. The physiological stress response produced by pain is characterised by increased heart and respiratory rates in response to increased demands for oxygen and nutrients by vital organs.
Pain can also worsen or prolong the stress response in seriously ill patients. Acute pain can have an important function in alerting us to an injury, and thus enabling us to protect the site from further injury. However, excessive or prolonged pain must be prevented or managed appropriately. While pain remains unrelieved, the hypothalamic pituitary adrenal (HPA) axis of stress response continues and the pain experienced is exacerbated.
Theme 5 Resource folder will have additional information for you.
You may also like to visit IASP web page for more information and resources heme 5 Learning guide – Topics 1-2
Classifications of pain
The Australian National Pain Strategy (2019) broadly describes five categories of pain that include:
Acute pain
Sub-acute pain that is progressing towards chronic pain but this progression may be prevented
Recurrent pain such as migraines
Chronic non-cancer pain and
Cancer-related pain.
These classifications are often broadly categorised as either acute or chronic pain.
Acute pain is usually associated with a known injury or incident, such as a twisted ankle, broken bone or following surgery. It has a definite onset, a predictable duration, and once healing is complete, the experience of pain is expected to subside (American Medical Association, 2018). The classic symptoms that often accompany acute pain reflect the sympathetic activity of the stress response, they include: tachycardia, tachypnoea, hypertension, pupil dilation and sweating.
Chronic pain can be defined as pain that persists beyond the time of healing of an injury, and can develop as a result of unresolved acute pain (American Medical Association, 2018). Please note that chronic pain had been defined as pain persisting for 3 months or more. However, this may be revised in future.
Pain can also be either nociceptive or neuropathic.
Nociceptive pain is caused by stimulation of sensory nerve endings called ‘nociceptors’ by a noxious chemical, mechanical or thermal stimulus.
Neuropathic pain is caused by physical damage or disease processes in sensory nerve fibres, or abnormal processing of sensory information in the peripheral and central nervous systems.
Nociceptive pain can be further classified as either somatic, visceral, or referred.
Somatic pain arises from the body wall, skin, connective tissues, head, neck and limbs
Visceral pain arises from the internal organs.
Pain that originates in one area of the body but is felt in a different area is called ‘referred pain’.
The following activity will provide you with some excellent information on the different types of pain
Recommended video
Sylvester, MJ 2013, Queen’s Meds 115: Family Medicine, Pain 1: Physiological types of pain, viewed 29 September 2019,
Theme 5 Learning guide – Topics 1-2
Pain pathways for nociceptive and neuropathic pain
The term ‘pain pathway’ describes the mechanism or pathophysiology of pain from the stimulus through to central perception or pain. The pain pathways for nociceptive pain and neuropathic pain both include the following major steps:
Transduction – the process whereby a stimulus is converted to a neuronal action potential (nerve impulse)
Transmission – the process whereby the action potential is passed to, and through, the CNS to the areas of the brain where perception occurs
Modulation – the body’s mechanism for inhibiting pain
Perception – the process of conscious awareness of pain
Recommended videos
Jackson, P 2014, The Pain Pathway. video, 03 March, viewed 29 September 2019,
Theme 5 Learning guide – Topics 1-2
Pain pathways for referred pain
Another type of pain you will have either witnessed or experienced is referred pain. This is when damage occurs in one location but the sensation of pain is experienced in a different location. Most referred pain is visceral in origin, though there are some exceptions.
A common example of referred pain is in patients experiencing myocardial ischaemia. The damage occurring is in the heart muscle (viscera) but the pain may present in their jaw, or as a tight/heavy feeling in their upper chest or an ache/heaviness down their left arm. This may occur because the nerves involved in the transmission of noxious stimuli from the heart travel down similar pathways as sensations coming from the anterior chest wall, forearms and hands – the origin of the nerves are the same having developed from the same tissue embryologically. Consequently interpretation of data in the brain may become confused and messages may be misinterpreted as somatic rather than visceral.
Another example of referred pain is shoulder tip pain following laparoscopy. This is caused by irritation of the phrenic nerve secondary to the air that has been inserted into the peritoneum.
A much more common type of referred pain is ‘ice-cream headache’ when you eat ice-cream or drink an icy cold drink and you experience pain in your head. This occurs because the vagus nerve in the throat and the trigeminal nerve in the palate transmit pain signals as a result of the rapid cooling then rewarming of the capillaries in the sinuses. So next time you experience ‘ice-cream headache’ think about the physiology of referred pain!
heme 5 Learning guide – Topics 1-2
Patient experience of pain
The experience of acute pain results in a ‘fight-or-flight’ stress response. This process initiates the neurohormonal changes previously discussed as well as production of natural endorphins and noradrenaline. These factors feed back into the modulation of pain and thus influence the patient’s pain experience. For example, in cases of acute pain, someone with a traumatic injury may not report severe pain or experience a stress response immediately following the initial incident. However, if pain levels increase for any reason, the stress response will once again kick in.
In cases of chronic pain, a continued ‘fight-or-flight’ response can occur, which can result in endocrine and immune malfunction, and impair the body’s capacity to modulate pain. Patients with chronic pain may also experience frustration, lethargy, sadness, grief, depression and a reduced ability to maintain daily activities. The biopsychosocial model of pain suggests that psychological responses to pain, such as attention, beliefs and learnt responses can contribute to modulation of the physical experience of pain, and may lead to pain-related fear and avoidance behaviours.
Recommended video
Understanding pain: what to do about it in less than five minutes. video, n.d., viewed 29 September 2019
Hunter Integrated Pain Service. Available URL: http://www.hnehealth.nsw.gov.au/Pain/Pages/Brainman-Videos.aspx
Theme 5 Learning guide – Topics 1-2
Clinical applications
The pain processes discussed so far form the basis for medical and nursing management of pain using analgesics, anaesthesia, and a range of other strategies. These will be discussed in other subjects within this course.
It is important to remember that while analgesics are extremely important in the management of pain, they are not the only option. Pain can to some extent be modulated by other strategies, including:
rubbing the painful area
applying cool or warm mediums
psychosocial support
relaxation techniques
cognitive behavioural interventions.
Please note that this is not a comprehensive list! You will need to investigate these and other techniques in more detail throughout the remainder of this course.
You may find further information on understanding and managing acute and chronic pain on the Pain Australia website available at heme 6 Learning guide: Immunology concepts – Introduction
Why study this theme?
Immunology is a vast and rapidly growing subject resulting in new medical specialities such as psychoneuroimmunology and immunosenescence. We are continually learning more about the intricate processes of the immune system and its integration and effect on other body systems. The stress response has a significant effect on various immune system functions.
You have already been introduced to the concepts of psychoneuroimmunology and the stress response in earlier themes, and have learned of the impact of these on immune function.
This theme will build on your existing knowledge and has been divided into the following topics. Topic 1 covers a lot of physiology, which we relate to clinical practice in Topic 2 through the use of clinical scenarios and the prescribed case studies.
Topic 1 – Immune system roles and functions
The first topic in this theme focuses on immune system physiology, which may be revision for some of you, but may be new for others.
Topic 2 – Effect of stress on immune function
The second topic builds on what you have learned about the stress response in earlier themes and explores the effect of stress and the stress response on immune function. The specific effects of ageing, pain, acute and chronic illness will be addressed because they have a profound effect on immune function.
The learning concepts in this theme are:
Content in the theme will explore:
concepts of innate and adaptive immunity
the effects of the stress response on immune function
the effects of ageing and illness on the immune system
clinical scenarios to ascertain the impact of stressors on immune function.
Text and images in this theme were authored by Christine Mackey.w.painaustralia.org.au Theme 6 Learning guide: Immunology concepts – Introduction
An immunology metaphor
The concept of the immune system and how it provides protection for the body is frequently envisaged as a medieval castle. The medieval castle has different levels of fortification, as well as various standard of soldiers, knights, kings and queens armed at each level that forms some kind of physical barrier to invading forces and can be seen here in Figure 6.1.
The immune system has three levels of defence:
outer barriers of the castle moat – similar to the surface barriers of the body
castle wall – can be likened to the innate immune system
inside the castle – similar to the adaptive immune system.
Figure 6.1: Levels of immune defence (Mackey, 2013)
As you read through this theme it can be useful to reflect on the different levels of protection provided by the physical walls and fortifications of a castle, and the interplay of all the members of the armed forces of the castle. Relate which element of the immune system correlates to these and you will start to see the synergies between the two systems in play. Theme 6 Learning guide: Immunology concepts – Introduction
Definitions
Throughout this theme, we will be using various physiological terms, many of which you should already be familiar with, but some of which may be new to you. The following list of terms are from the prescribed textbook and the page numbers correlate to the section of the textbook where you will see the terms in context. You may wish to review and add to this list to check your knowledge of these terms before you continue with the theme.
Antibody
a protein molecule that is released by a plasma cell and that binds specifically to an antigen; an immunoglobulin
Antigen
a substance or part of a substance that is recognised as foreign by the immune system, activates the immune system, and reacts with immune cells or their products
Antigen presenting cell (APC)
a specialised cell that captures, processes, and presents antigens on its surface to T lymphocytes
Chemotaxis
movement of a cell, organism, or part of an organism toward or away from a chemical substance
Clone formation
cloning is the formation of descendant cells from a single cell. In the context of immunology, clone formation refers to activation and proliferation of lymphocytes with the same antigen-specific receptors
Co-stimulation
additional surface proteins on APCs that produce stimulatory signals required for T cell activation
Cytokines
small proteins that act as chemical messengers between various parts of the immune system
Diapedesis
passage of white blood cells between cells of an intact vessel wall
Hapten
an incomplete antigen; has reactivity but not immunogenicity
Immune surveillance
cells that roam the body examining surfaces of other cells for markers they might recognise
Specialised Stellate Macrophages (Kupffer cells)
are specialised macrophages that form part of the lining of the sinusoids of the liver that remove debris and dead RBCs
Leucocytosis
An increase in the number of white blood cells; usually the result of a microbial attack on the body
Macrophages
protective cell type common in connective tissue, lymphoid tissue, and many body organs; phagocytizes tissue cells, bacteria, and other foreign debris; presents antigens to T cells in the immune response
Mucosa-associated lymphoid tissue (MALT)
the collection of lymphoid tissue in mucous membranes – e.g. tonsils, Peyer’s patches, Appendix
Margination
phenomenon where phagocytes cling to the inner wall margins of capillaries in response to signal by inflammatory chemicals
Neutrophils
most abundant type of white blood cell
Peyer’s patches
Lymphoid tissue located in the mucosa of the small intestine – see MALT
Phagocytosis
Engulfing of foreign material by phagocytic cells
T cell activation
a two-step process where APCs undergo antigen binding and co-stimulation to activate the T-cell.
Adopted from:
Marieb, E. N., & Hoehn, K. (c2018). Human anatomy and physiology (11th ed. Global ed.).
Pearson Education. 9781292261034
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