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| - | Add intro image | + | {{:rsz_alzh.png|}} |
| =======Alzheimer's Disease Powerpoint======= | =======Alzheimer's Disease Powerpoint======= | ||
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| ===== INTRODUCTION ===== | ===== INTRODUCTION ===== | ||
| - | blah | + | Alzheimer’s disease is a type of dementia specifically targeting areas of the brain responsible for memory, behaviour and language. Throughout the progression of this disease, neurons lose their ability to properly communicate, causing cell death in these regions. Alzheimer’s is a progressive disease where its symptoms accumulate very slowly, and worsen over time (da Silva, 2017). Beginning stages are typically very mild, however eventually individual’s lose the ability to engage in everyday tasks such as having meaningful conversation and responding to environmental cues. Though Alzheimer’s is not a normal side effect of aging, its greatest risk factor is age. However, approximately five percent of people between the ages of 40-50 develop early-onset Alzheimer’s (da Silva, 2017). |
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| + | Alzheimer’s is the most common neurodegenerative disease. Individuals diagnosed with this disease live approximately eight years after symptoms become noticeable (Alzheimer's Association, 2011). This is a result of the progressive nerve cell death and tissue loss within the brain. Consequently, as an individual continues to age the size of the brain drastically shrinks, causing loss of function to almost all areas. | ||
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| + | <box 65% round | > {{:brain_comparison.png|}} </box| Figure 1 - Brain size comparison between a healthy and advanced Alzheimer’s brain. (Alzheimer’s Association, 2011))> | ||
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| =====SIGNS & SYMPTOMS===== | =====SIGNS & SYMPTOMS===== | ||
| - | blah | + | Though there are many signs of early onset Alzheimer’s, five of the major symptoms include: |
| + | - **Memory loss**: I.e. forgetting important dates or repeatedly asking the same question | ||
| + | - **Difficulty with familiar tasks**: I.e. not being able to drive to familiar locations | ||
| + | - **Confusion with time or place**: I.e. losing track of dates/seasons | ||
| + | - **New issues with speaking or writing**: I.e. trouble following/ joining a conversation | ||
| + | - **Changes in mood and personality**: I.e. becoming confused, depressed and anxious | ||
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| + | <box 90% round | > {{:ad.png|}} </box| Figure 2 - Common symptoms of Alzheimer’s. (Cephalicvein, 2016)> | ||
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| ===== EPIDEMIOLOGY ===== | ===== EPIDEMIOLOGY ===== | ||
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| * Alzheimer’s is least prevalent in Sub-Saharan Africa. | * Alzheimer’s is least prevalent in Sub-Saharan Africa. | ||
| * Alzheimer’s and other dementias are the top cause for disabilities in later life. (Alzheimer’s Disease International, 2015) | * Alzheimer’s and other dementias are the top cause for disabilities in later life. (Alzheimer’s Disease International, 2015) | ||
| - | <box 90% round | > {{:epia.png|}} </box| Figure ## - Projected growth of Dementia in the world in several areas. (Alzheimer's Disease International, 2015) > | + | <box 70% round | > {{:epia.png|}} </box| Figure 3 - Projected growth of Dementia in the world in several areas. (Alzheimer's Disease International, 2015) > |
| The incidence of AD is approximately 5–8 for per thousand person, which represents half of new dementia cases each year are AD (Bermejo-Pareja et al, 2008). One of the primary risk factor for AD, where there is a correlation of the incidence rate of every five years after the age of 65, the risk of acquiring AD approximately doubles (Di Carlo et al, 2002). Furthermore, there is also higher incidence rates in women compared to men of developing AD particularly in the population older than 85 (Andersen et al, 1999). | The incidence of AD is approximately 5–8 for per thousand person, which represents half of new dementia cases each year are AD (Bermejo-Pareja et al, 2008). One of the primary risk factor for AD, where there is a correlation of the incidence rate of every five years after the age of 65, the risk of acquiring AD approximately doubles (Di Carlo et al, 2002). Furthermore, there is also higher incidence rates in women compared to men of developing AD particularly in the population older than 85 (Andersen et al, 1999). | ||
| In the United States, Alzheimer prevalence was estimated to be 1.6% in 2000 both overall and in the 65–74 age group, with the rate increasing to 19% in the 75–84 group and to 42% in the greater than 84 group. (Hebert et al, 2003) Prevalence rates of AD is less in developed countries compared to developing countries (Ferri et al, 2006). AD accounts to 50-70% of all forms of dementia, making it the leading cause of this neurodegenerative disease (7). Furthermore, due to the rapid increase of dementia, individuals would also be at increased risk of AD. Another study estimated that in 2006, 0.40% of the world population were afflicted by AD, and that the prevalence rate would triple and the absolute number would quadruple by 2050. (Brookmeyer et al, 2007) | In the United States, Alzheimer prevalence was estimated to be 1.6% in 2000 both overall and in the 65–74 age group, with the rate increasing to 19% in the 75–84 group and to 42% in the greater than 84 group. (Hebert et al, 2003) Prevalence rates of AD is less in developed countries compared to developing countries (Ferri et al, 2006). AD accounts to 50-70% of all forms of dementia, making it the leading cause of this neurodegenerative disease (7). Furthermore, due to the rapid increase of dementia, individuals would also be at increased risk of AD. Another study estimated that in 2006, 0.40% of the world population were afflicted by AD, and that the prevalence rate would triple and the absolute number would quadruple by 2050. (Brookmeyer et al, 2007) | ||
| - | <box 90% round | > {{:deathsa.png|}} </box| Figure ## - Deaths due to Alzheimer's in 2012 (Red indicating larger number of deaths compared to orange). (Wikipedia, 2013) > | + | <box 70% round | > {{:deathsa.png|}} </box| Figure 4 - Deaths due to Alzheimer's in 2012 (Red indicating larger number of deaths compared to orange). (Wikipedia, 2013) > |
| - | <box 90% round | > {{:resized.png|}} </box| Figure ## - The prevalence and incidence rates in various areas compared to an age category. (Qiu, Kivipelto & Strauss, 2009) > | + | <box 70% round | > {{:resized.png|}} </box| Figure 5 - The prevalence and incidence rates in various areas compared to an age category. (Qiu, Kivipelto & Strauss, 2009) > |
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| - | ===== DIAGNOSIS ===== | + | ===== PATHOPHYSIOLOGY ===== |
| - | blah | + | The early onset of Alzheimer’s disease (AD) is marked by neuronal loss occurring within the entorhinal cortex of the brain, which is located under the cerebral cortex (Columbia University Medical Center, 2013). The major function of this region of the brain is to submit information to and from structures in the hippocampus. The hippocampus then accumulates this information and stores it as long-term memory. Any pathology in these areas of the brain would affect an individual’s memory, being as they are so closely associated with memory processing (Saylor, 2017). Additionally, pathology is also seen in the amygdala, a region accountable for emotional responses and behaviour to various stimuli (Saylor, 2017). During the moderate onset of AD, cortical and hippocampal atrophy continues, alongside the widening of cerebrospinal fluid-filled ventricles within the brain (Salcudean, 2010). This ventricle widening causes further damage to surrounding tissues in the brain. A patient affected by AD may experience an inability to accomplish daily tasks, increased anxiety and emotional outbursts, and language impairment among several other symptoms as their memory loss continues. The severe (late) stage of dementia is characterized by the presence of two major neuropathological trademarks including intracellular neurofibrillary tangles and extracellular amyloid plaques (Salcudean, 2010). At this point, irreversible neuronal loss is evident throughout the brain, causing extensive dysfunction and extreme atrophies to affected areas (see Figure 6). This individual would experience severe loss of autonomic functions and would require complete dependence on others for care. |
| + | <box 45% round | >{{:brain-w550.jpg|}} </box|Figure 6: Normal brain vs. Brain affected with Alzheimer's Disease. Atrophy of cerebral cortex, and hippocampus is shown, as well as enlarged ventricles (Whole Health Insider, 2013)> | ||
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| - | ===== PATHOPHYSIOLOGY ===== | + | Amyloid precursor proteins (APP) are constantly released during normal metabolism in the brain. Little is understood about the functioning of these proteins, especially regarding its part in the pathogenesis of AD (Lin, 2001). APP can be cleaved by α-secretase proteases, which would result in normal functioning of the brain, and no buildup of extracellular amyloid plaque (Lichtenthaler, 2012) (See left hand side of Figure 7). However, if the APP molecule is cleaved by β-secretase and/or γ-secretase, amyloid-β peptide fragments are released into the extracellular space due to an abnormal cleavage of the protein by these enzymes (Salcudean, 2010). In small amounts, this procedure is not harmful and may even be desirable for normal synaptic functioning. More often than not, however, the over activity of these β- and γ-secretase enzymes cause a large, toxic amount of amyloid-β peptide fragments. In excessive amounts, these fragments aggregate and form plaque in the extracellular space (see right hand side of Figure 7). PSEN1 and PSEN2 (Presenilin 1 and 2 respectively) play a part in regulating APP processing through γ-secretase, but mutuations in these protein molecules increase γ-secretase activity, which can lead to even more plaque formation (Salcudean, 2010). A huge component of these plaques are found throughout the brains of patients affected by AD, showing that they may play a huge role in the loss of functioning of the brain in these individuals (Lin, 2001). |
| - | Breast Cancer is similar to other cancers in which abnormal cell growth can potentially invade and spread to other areas of the body. In normal cell growth, cells can divide as necessary and have functioning signals that can stop cell division. These cells stay attached and localized in their respective sites and do not spread or invade other areas. Normal cells can also undergo programmed cell death, which keeps a balance in the cell population and discards unnecessary cells (Hartwell & Kastan, 1994). | + | <box 45% round | > {{:screen_shot_2017-03-04_at_8.35.30_pm.png|}} </box| Figure 7: Normal cleavage vs Abnormal cleavage of the APP molecule by proteases (da Silva, 2015).> |
| - | ==== The P13K Pathway and HER2 Gene ==== | ||
| - | The P13K pathway is an example of one of the most important pathways that protect cells by controlling functions such as cell growth, differentiation, motility, survival, and proliferation. P13Ks are lipid kinases that phosphorylate phosphoinositides. The P13Ks involved in breast cancer are Class 1A, which are comprised of a regulatory subunit (p85) and a catalytic subunit (p110). The activation of the P13K is initiated from growth factor or ligand binding to its respective receptor tyrosine kinase (RTK). These receptors contain two important growth factor receptors; the human epidermal growth factor receptor (HER) family and the insulin-like growth factor 1 receptor (IGF-1R). Once activated by a receptor, the P13K heterodimer interacts with a portion of the p85. This binding removes the inhibitory effect of p85 on p1110 rendering the P13K pathway active. The activation leads to a cascade of events downstream of the pathway, resulting in diverse functions such as cellular metabolism, proliferation, differentiation and survival (Liang & Slingerland, 2003). | + | Similarly, the brains of patients with AD seem to have an abundant amount of intracellular neurofibrillary tangles (Salcudean, 2010). Microtubules run along the length of axons, simulating tracks for motor proteins like kinesin and dynein to use in transporting their neuron signals to other areas of the brain. The Tau protein binds to this microtubule to stabilize it and prevent its depolymerization (Salcudean, 2010) (See Figure 8 a). In normal physiology of a healthy neuron, protein kinases phosphorylate tau, lifting them off the microtubule and allowing the passage of the motor proteins along the track. After this passage, the tau dephosphorylates and reattaches to the microtubule, stabilizing it once again (Salcudean, 2010). This procedure is much different in pathology of a diseased neuron. Hyperphosphorylation of tau proteins occur, which causes tau to aggregate with other taus, forming tangles in the brain (See Figure 8 b). Neuron signaling is not able to function as normal when this occurs, and it seems to have a choking affect on nerve cells, killing them in abundance (Ballatore, 2007). |
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| - | In breast cancer this pathway is aberrantly hyperactive, as shown in Figure __. This results from mutations in various parts of the pathway but most predominantly in PIK3CA, which encodes for the catalytic p110a subunit. Mutations in these promote downstream signaling elements such as Akt that increase enzymatic function. The overexpression of p110a subunit, therefore leads to robust activation of the pathway (Berns et al., 2007). P13K pathway also involves tumor suppressors such as PTEN, which turn off the pathway and induce cell death. However, in cases such as breast cancer, the PTEN protein may be mutated and unable to turn off the pathway. Therefore, there is excessive cell proliferation and the cell does not undergo programmed cell death. In this case, low expression of PTEN leads to excessive cell growth (Depowski, Rosenthal, & Ross, 2001). | + | |
| - | <box 80% round| > {{:f1.large1.jpg|}} </box| Figure 5 - PTEN Pathway and Mutations Retrieved from: http://theoncologist.alphamedpress.org/content/16/suppl_1/12/F1.expansion> | + | <box 45% round | > {{:screen_shot_2017-03-04_at_9.05.44_pm.png|}} </box| Figure 8: Healthy vs. Diseased neuron and formation of intracellular neurofibrillary tangles (Brunden, 2008).> |
| + | Thus, both these processes are seen in many patients that suffer from AD. However, there are some patients with AD that do not seem to have mutations in their APP, PSEN1 and PSEN2 genes. This insinuates that some forms of this dementia can be associated with alterations in other genes that have yet to be identified by scientific research (Mayo Foundation for Medical Education and Research, 2016). | ||
| - | ==== The HER2 Gene ==== | ||
| - | The ErbB is a family of receptor tyrosine kinases, which include the Her2 (ErbB2) receptor-tyrosine-protein kinase. Both the P13K/AKT pathway and Ras-Raf-MAPK pathway are important signalling routes for the ErbB protein. In normal cell activity, the ErbB protein forms homodimers and heterodimers upon activation by growth factor ligands. Upon dimerization these proteins become autophosphorylated and act as binding sites for intracellular signal activators. This triggers a signal cascade leading to increased cell proliferation and inhibition of apoptosis (cell death). Mutation in the HER2 gene leads to amplification of this oncogene and excessive ErbB signalling. Therefore, this increased signalling leads to aberrant cell proliferation and increased inhibition of cell apoptosis (Mitri, Constantine, & O’Regan, 2012). | ||
| - | ==== Types of Abnormalities ==== | + | ---- |
| - | Figure shows the various types of abnormalities that can result from abnormal cell growth. Ductal hyperplasia contains lesions in the breast that are not cancerous but have active growth and division in the breast tissue cells. Atypical Ductal Hyperplasia and Ductal Carcinoma In Situ (DCIS) occurs when breast tissue is beginning to take an abnormal appearance, however the abnormal cells are still localized in within the tissue. In DCIS-microinvasion and Invasive ductal cancer, the excessive cell growth spreads outside of the tissue and invades other areas of the body (Hüsemann et al., 2008). | + | ===== DIAGNOSIS ===== |
| - | <box 40% round| > {{:untitled_copy.jpg|}} </box| Figure 6 - Type of Abnormalities. (Da Silva, R. (2015) Module 3 Lecture 2: Breast Cancer[PowerPoint Slides]. Retrieved from McMaster University Health and Disease)> | + | Alzheimer’s Disease can be categorized into three stages; Early, Mild-to-severe, and Advanced. The clinical diagnosis is most often made during the mild-to-severe stage. Nonetheless, definitive diagnosis of Alzheimer’s can only be made post-mortem by examining brain tissues (Dubois et al., 2014). |
| + | Clinicians can diagnose the presence of Alzheimer’s disease with an adequate amount of certainty using several factors. These factors include the individual’s medical history, history from relatives, behaviour observations, presence of characteristic neurological and neuropsychological features, and the absence of alternate conditions (Dubois et al., 2014). This probable diagnosis of Alzheimer’s Disease can be made with approximately 90% confidence based on the stated criteria. Clinicians focus heavily on a combination of both brain imaging and clinical assessments for diagnosis, particularly focusing on declining mental ability (Dubois et al., 2014). In order to identify the presence of neurological features, a number of brain imaging techniques are used, such as, computed tomography (CT), magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT), and positron emission tomography (PET). These can not only be used to identify presence of neurological features characteristic of Alzheimer’s disease, but also exclude other pathology or subtypes of dementia that may be mistaken for Alzheimer’s Disease (McKhann et al., 2011) . Figure 9 shows a PET scan in which we can compare a healthy brain to a mild-to-moderate Alzheimer’s Disease brain. Not only is there a shrinkage in mass of the Alzheimer’s Disease brain, but glucose metabolism, indicated by the red probe, seems to be significantly decreased in the Alzheimer’s Disease brain relative to the healthy brain (Landau et al., 2014). In addition, assessment of the individual’s intellectual functioning can further help support a diagnosis. The Mini-Mental State Examination (MMSE) is the most common administered test to evaluate cognitive impairments such as problems with memory, attention and language. Further examinations are crucial to diagnose Alzheimer’s with sufficient certainty, including, interviews with family members and caregivers, who can provide important information about daily living abilities (McKhann et al., 2011). | ||
| + | <box 40% round | > {{:picture1222.jpg|}} </box| Figure 9 - Healthy brain vs. Alzheimer's Disease brain in the mild-to-moderate stage (daSilva, 2015)> | ||
| - | ==== Spread of Malignant Tumours ==== | + | It is vital to also identify biomarkers that will help assess risk, diagnosis, and monitor the progression of the disease (Hansson et al., 2006). They can provide valuable indications of health and disease, and contain high sensitivity and specificity that defines their diagnostic utility (Humpel, 2011). Biomarkers can help distinguish between different types of dementias that may appear very similar to Alzheimer’s Disease. There are no specific biomarkers that can confirm Alzheimer’s Disease with 100% certainty. However, it is possible to use measurements of B-amyloid (1-42), total tau, and phosphorylated-tau—181 in the cerebrospinal fluid as biomarkers for Alzheimer’s Disease (Humpel, 2011). The combination of all three can significantly increase the diagnosis of Alzheimer’s Disease (Humpel, 2011). In patients with Alzheimer’s, due to aggregation of B-Amyloid (1-42) in the brain, B-amyloid (1-42) would essentially be reduced in the cerebrospinal fluid, whereas total tau and phosphorylated tau would be enhanced (Humpel, 2011). |
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| - | The spread of the tumour varies with different stages in breast cancer. Usually, the least progressive is when atypical cells are in the breast tissue and there are no signs of spread to lymph nodes. As the tumour size increases it begins to spread to lymph nodes and there is metastases in axillary lymph nodes. From here the tumours of any size may spread into the skin, chest wall, and eventually the cancer spreads to other organs and tissues (Hüsemann et al., 2008). | + | |
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| - | The cancer cells are able to spread to various areas of the body by penetrating the extracellular matrix and blood vessels. Cells are constrained in their respective organs by cell-cell adhesion and basement membrane. However, cancer cells can penetrate the basement membrane by using invadopodia. Invadopodia is the process in which cells form actin-rich protrusions in the plasma membrane and subsequently degrade the extracellular matrix. Genes involved in these protrusions and invasions are upregulated in malignant cancer cells, allowing increased cell invasion and motility. This way, some cells contained in the tumour can separate from their parent mass and enter vascular and lymphatic circulation (Linder, 2007). | + | |
| + | Candidate gene studies for Alzheimer’s Disease do not allow conclusive evidence for the presence of disease beyond a simple hypothesis. The Genome-wide association studies (GWAS) test many genetic markers to detect the presence of diseases related to Alzheimer’s Disease. This form of study is most often used in clinical trials rather than clinical diagnosis (Bertram & Tanzi, 2009). | ||
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| ===== CURRENT TREATMENTS ===== | ===== CURRENT TREATMENTS ===== | ||
| - | There are many procedures to treat breast cancer ranging from invasive to non-invasive treatments. One of the least invasive treatments is a lumpectomy, which is considered breast conserving surgery. This form of treatment aims to remove any abnormal masses within the breast, without removing all breast tissue (Fisher et al, 1993). Along with the mass itself, a layer of surrounding tissue, specifically regions near the axillary nodes, are also extracted to ensure cancer has not spread to neighboring regions (Fisher et al, 1993). However, due to the conservation of most breast tissue, this method is most effectively used at the earliest stages of breast cancer, before it has spread to multiple layers of tissue. | + | Similar to the diagnosis of the disease, there has yet to be an effective cure for Alzheimer’s Disease. Although there are several treatments available that help treat the symptoms of the disease, they provide relatively few benefits. They have not shown to delay the onset of AD or halt the progression of the disease. Current treatments can be pharmaceutical, psychosocial and caregiving in nature (Yiannopoulou & Papageorgiou, 2013). |
| - | One of the most commonly used treatments is a mastectomy. This is because a lot of breast cancer cases are reported late, after cancer has already spread to multiple layers of tissue. Using this method all of the breast tissue, including the nipple and areola is removed on the affected breast(s) (Canadian Cancer Society, 2017). Once removed, the skin is stitched closed with a temporary tube attached to an opening in the wound, allowing for any fluid post-surgery to be removed safely (Canadian Cancer Society, 2017). After surgery, a pathologist examines the removed tissue to determine the extent of cancer penetration, and detect whether it has spread to neighboring regions. Since the axillary nodes have the highest likelihood for cancer to spread from the breasts, a few lymph nodes are also removed during surgery for examination (Canadian Cancer Society, 2017). If cancer has appeared to spread to other regions, then other treatments may be used in conjunction with a mastectomy, such as radiation therapy, in order to kill all remaining cancer cells. | + | Pharmaceutical treatments include acetylcholinesterase inhibitors and as well as a NMDA receptor antagonist. Donzepil, Rivastigmine, and Galantime are acetylcholinesterase inhibitors most often used in the mild-to-moderate stage of the disease (Lahiri, Greig, & Sambamurti, 2002). Alzheimer’s Disease is correlated with a decrease in the activity of cholinergic neurons, and these drugs inhibit the activity acetylcholinesterase (breakdown of acetylcholine), therefore increasing the concentration of acetylcholine in the brain. Approximately 20% of patients taking one of these three drugs may show common side effects associated with cholinergic excess such as, nausea and vomiting (Lahiri, Greig, & Sambamurti, 2002). Memantine is a NMDA receptor antagonist, which is predominantly used in the moderate-to-severe stages of the disease (Reisberg et al., 2003). In Alzheimer’s Disease the excitatory neurotransmitter Glutamate is overstimulated, ultimately causing cell death though a process known as excitotoxicity. Memantine acts on the glutamatergic system by inhibiting the overstimulation of glutamate. Common side effects of this drug include, hallucinations, confusion, fatigue, headache, and dizziness (Reisberg et al., 2003). |
| - | Radiation therapy is a form of treatment that targets specific suspected regions. This type of therapy uses high-energy X-rays to assist in targeting and killing cancer cells (Canadian Cancer Society, 2017). Due to its ability to target cells, this form of treatment is typically used post-surgery in order to kill any remaining cancer cells that were missed during surgical procedures. This form of treatment used alone is an option for those experiencing early stage breast cancer, when all the cancer cells are contained within a specific region. However, radiation therapy is also an option for individuals with more advanced breast cancer if used in combination with other forms of treatment such as surgery or chemotherapy (Canadian Cancer Society, 2017). | + | <box 75% round | > {{:treatments22.jpeg|}} </box| Figure 10 - Pharmaceutical Treatments Summarized (Lahiri, Grieg, & Sambamurti, 2002)> |
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| - | Majority of lumpectomy procedures are followed by radiation therapy to ensure the cancer is killed from remaining breast tissue (Fisher et al, 1993). By doing this it will lower the chance of breast cancer recurrence by 50 percent, along with death due to breast cancer events by approximately 20 percent (Fisher et al, 1993). In terms of a mastectomy, radiation therapy has not shown to be a beneficial post-procedure (Canadian Cancer Society, 2017). However, in rare cases when radiation therapy is used after mastectomy, its purpose is to treat neighboring regions that are highly susceptible to the spread of cancer, such as the chest wall and axillary nodes (Canadian Cancer Society, 2017). | + | |
| - | One of the most common forms of treatment for general cancer cases is chemotherapy. During this form of treatment tumors are treated with high levels of radiation to kill the rapidly diving cells (Canadian Cancer Society, 2017). This form of treatment targets cells non-specifically, and is therefore highly invasive as it kills both healthy and cancerous cells within the body. The radiation from chemotherapy causes the cells within the body to remain in the metaphase-anaphase stage during cell division, leading to apoptosis instead of replication (Canadian Cancer Society, 2017). Due to the killing of these cells there are high toxicity levels associated with this form of treatment which cause side effects such as hair loss, fatigue and nausea (Canadian Cancer Society, 2017). | + | In addition to pharmaceutical treatments, many Alzheimer’s patients will undergo psychosocial and caregiving treatments. Psychosocial treatments specifically target the cognition, emotion, behaviour, and stimulation-oriented aspects of the disease (Brodaty, Green, & Koschera, 2003). A common example of a psychosocial intervention is known as Reminiscence Therapy, in which patients are involved in a discussion of past experiences with photographs, music, and other familiar items. This type of intervention tends to show minor improvements in the cognition and mood of the patients (Sitzer, Twamley, & Jeste, 2006). Caregiving is essential to help patients who are incapable of carrying out common day-to-day activities. Both have received minimal scientific support but seem to be significant in helping patients adjust to the illness (Brodaty, Green, & Koschera, 2003). |
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| - | Chemotherapy is divided into two categories depending on when it is used. Chemotherapy done prior to surgery is referred to as Neoadjuvant therapy. This method is used to shrink large tumors before attempting surgery to increase the chances of successful lump extraction, preventing breast removal (Kuerer et al, 1999). Neoadjuvant therapy can also be used in those with larger tumors in need of a mastectomy. In this case it would be used to increase the chances of tumor shrinkage, and promote a lumpectomy breast conserving procedure instead. Treatment this way also monitors how the tumor responds to treatment, making it safer for tumor removal (Kuerer et al, 1999). Chemotherapy used post surgery is referred to as Adjuvant therapy. This method is given to those who have no current evidence of containing cancer cells in their body (Kuerer et al, 1999). The purpose of adjuvant therapy is to kill the cancer cells that may potentially have been left behind or have metastasized, to reduce the risk of recurrence. | + | ===== FUTURE TREATMENTS ===== |
| + | Researchers are continually looking at possible ways to delay and halt the progression of Alzheimer’s Disease. Current treatments only provide minimal relief to the symptoms of the disease and not the underlying disease itself. | ||
| - | Patients who have been diagnosed with estrogen-receptor positive tumors often experience beneficial results from undergoing endocrine therapy (Lumachi et al, 2011). This type of therapy is usually done through oral contraceptives containing specific estrogen-receptor modulators (SERMs) (Lumachi et al, 2011). A few of the most commonly used SERMs are aromatase inhibitors, GnRH agonists and tamoxifen. Aromatase inhibitors decrease estrogen levels, whereas tamoxifen blocks estrogen receptors, both of which aim to either decrease the tumor’s size or delay its growth (Lumachi et al, 2011). Since endocrine therapy is used amongst those with estrogen-receptor positive tumors, women are classified as premenopausal or postmenopausal in order to determine which method of treatment to undergo. Women in the premenopausal stage who have the estrogen/progesterone receptor are normally treated with tamoxifen for a length of five years (Lumachi et al, 2011). This drug’s ability to block estrogen receptors lowers the risk of breast cancer recurrence by approximately 50 percent (Lumachi et al, 2011). Alternatively, women who are postmenopausal and estrogen-receptor positive have higher beneficial rates from adjuvant therapy, using an aromatase inhibitor (Lumachi et al, 2011). Since postmenopausal women still produce low levels of estrogen in specific fatty tissues, such as the breast tissue, this estrogen-lowering drug reduces the amounts of hormones which contribute to breast cancer growth. | + | Some possible therapeutics include drugs that decrease the production of B-amyloid plaques and tau tangles, removing the toxic aggregates, or preventing the aggregation (Yiannopoulou & Papageorgiou, 2013). |
| - | ---- | + | Figure 11 depicts therapeutics that target Tau aggregates through kinase inhibitors, which block the formation of the tau aggregates (Yiannopoulou & Papageorgiou, 2013). |
| - | ===== FUTURE TREATMENTS ===== | + | <box 40% round | > {{:picture122.jpg|}} </box| Figure 11 - Possible therapeutics targeting tau aggregates (daSilva, 2015)> |
| - | To continue declining mortality rates, some future treatments and screening technologies that are in the process of being introduced, focus on more micro areas of the disease. A new screening technology called Scintimammography, which is molecular breast imaging, uses a radioactive drug called Tracer which is injected into the patient. The drug travels to the breasts via circulation and attaches to breast tissue cells (American Cancer Society, 2016). The radioactive substance is then detected by a special camera called a cadmium-zinc-tullerida gamma camera. The significance of this piece of technology is its beneficial detection of small tumours which other current screening technologies lack in advancement (Rhodes, 2005). This screening technology is able to give an early diagnosis to certain cases that show no symptoms of the disease in earlier stages, leading to declines of mortality rates. (Rhodes, 2005). | + | |
| + | Figure 12 shows four distinct ways amyloid specific antibodies may be able to degenerate the B-amyloid plaques (Yiannopoulou & Papageorgiou, 2013). | ||
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| + | <box 40% round | > {{:picture133.jpg|}} </box| Figure 12 - Possible therapeutics targeting B-amyloid plaques (daSilva, 2015)> | ||
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| + | In addition to future treatments, it is important to focus on advancing research and development in biomarkers that can help assess risk and monitor the underlying disease. | ||
| - | Future treatments are underway. These specific treatments are called target therapies and are a group of drugs which target specific changes in genes of cancer cells, a preventative measure in cancer cell proliferation. Some of these target therapies include PARP inhibitors. PARP inhibitors target the BRCA mutations (American Cancer Society, 2016). These target drugs have shown success in some types of breast cancers and are further being studies to determine exactly when these drugs have their highest potential to be helpful in treatment. Another target therapy in current research is anti-angiogenesis drugs, which refers to the blocking process of angiogenesis. Fast growing cancer cells require blood cells to nourish their cell bodies. Therefore preventing the proliferation and rapid growth of the cancer cells, blocking angiogenesis may be helpful in slowing down the disease (American Cancer Society, 2016). | ||
| - | <box 75% round| > {{:3qtgdv.jpg|}} </box| Figure 7 - (Zetter, 2008)> | ||
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| === References === | === References === | ||
| + | Alzheimer's Association. (2011). Healthy Brain Versus Alzheimer's Brain. Retrieved March 03, 2017, from http://www.alz.org/braintour/healthy_vs_alzheimers.asp | ||
| - | Ballo, M. S., & Sneige, N. (1996). Can core needle biopsy replace fine‐needle aspiration cytology in the diagnosis of palpable breast carcinoma: A comparative study of 124 women. Cancer, 78(4), 773-777. | + | Alzheimer's: Is it in your genes? (n.d.). Retrieved March 4, 2017, from http://www.mayoclinic.org/diseases-conditions/alzheimers-disease/in-depth/alzheimers-genes/art-20046552?pg=2 |
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