Neurology Flashcards
(380 cards)
1
Q
Main types of cells in the nervous system?
A
Neurons: Functional units that transmit signals.Glial Cells: Support, protect, and nourish neurons.
2
Q
Roles of neurons and glial cells?
A
Neurons: Transmit electrical signals for communication.Glial cells: Support, nourish, and protect neurons; maintain homeostasis.
3
Q
Neurons and brain complexity?
A
Enable communication between different brain regions.Connections and synapses indicate brain complexity and functionality.
4
Q
Significance of glial cells?
A
Support neurons structurally and functionally.Maintain brain health by regulating the environment.
5
Q
Key components of a pyramidal neuron?
A
Cell body: Contains the nucleus.Axons: Transmit signals away from the cell body.Dendrites: Receive signals from other neurons.Dendritic spines: Sites for synaptic connections.
6
Q
Signal transmission in pyramidal neurons?
A
Electrical signals travel through dendrites to the cell body, then down the axon to communicate with other neurons.
7
Q
Shape of pyramidal neuron?
A
Triangular shape, which facilitates connections with other neurons.
8
Q
Distinct parts of a neuron?
A
Cell body: Contains the nucleus and organelles.Long axon: Conducts impulses away from the cell body.Dendrites: Branching structures that receive signals.
9
Q
Role of dendritic spines?
A
Facilitate synaptic transmission and increase the surface area for connections.
10
Q
Main components of the CNS?
A
Brain: Central organ of the nervous system.Spinal Cord: Transmits signals between the brain and body.
11
Q
Main divisions of the Nervous System?
A
CNS: Central Nervous System (brain and spinal cord).PNS: Peripheral Nervous System (nerves outside the CNS).
12
Q
Role of the Cerebrum?
A
Largest part of the brain responsible for higher mental functions, sensory processing, and voluntary movement.Involved in reasoning, problem-solving, and emotions.
13
Q
Components of the PNS?
A
Spinal nerves: Connect the spinal cord to the body.Cranial nerves: Connect the brain to the head and neck.Parasympathetic nerves: Regulate involuntary functions.
14
Q
Cerebellum location?
A
Located below the cerebrum, at the back of the brain.
15
Q
Dendritic spines and axon terminals?
A
Dendritic spines: Sites for synapse formation with axon terminals.
16
Q
Main parts of the brainstem?
A
Midbrain: Involved in vision and hearing.Pons: Connects different parts of the brain.Medulla Oblongata: Controls vital functions like breathing and heart rate.
17
Q
Functions of the brainstem?
A
Regulates basic life functions such as heart rate, breathing, and blood pressure.Coordinates reflexes and movement.
18
Q
Brainstem connections?
A
Connects the cerebrum and cerebellum, facilitating communication between them.
19
Q
Cranial nerves and brainstem?
A
12 pairs of cranial nerves emerge from the brainstem, supplying the head and neck.
20
Q
Cranial vs spinal nerves?
A
Cranial: 12 pairs that emerge from the brain.Spinal: 31 pairs that emerge from the spinal cord.
21
Q
Types of grey matter in the spinal cord?
A
Sensory grey matter: Located posteriorly, processes sensory information.Motor grey matter: Located anteriorly, controls motor functions.
22
Q
Brainstem and movement coordination?
A
Essential for real-time corrections of movements and balance.
23
Q
Spinal cord and sensory/motor info?
A
Ascending tracts: Carry sensory information to the brain.Descending tracts: Carry motor commands from the brain.
24
Q
Spinal cord structure features?
A
White matter: Located outside, contains myelinated axons.Grey matter: Located inside, contains neuron cell bodies.
25
Lateral grey horn cells in the spinal cord?
Sympathetic: Located in the thoracolumbar region.Parasympathetic: Located in sacral segments.
26
Grey matter organization in the spinal cord?
Anterior: Contains motor neurons.Posterior: Contains sensory neurons.
27
Sympathetic and parasympathetic lateral grey horn cells?
Sympathetic: Found in thoracolumbar region.Parasympathetic: Found in sacral segments.
28
Main structures in scalp anatomy?
Skin and cutaneous tissue: Protects underlying structures.Loose connective tissue: Allows movement of the scalp.
29
Layers after scalp removal?
Loose connective tissue: Provides cushioning.Pericranium: Connective tissue covering the skull.
30
Skull cap significance?
Bone structure that protects the brain.
31
Three layers of meninges?
Pia mater: Innermost layer, adheres to the brain.Arachnoid: Middle layer, contains CSF.Dura mater: Outermost layer, tough protective layer.
32
Function of dura mater?
Thickest layer that protects the brain and spinal cord.
33
Meninges covering the brain?
Three layers: Dura mater, Arachnoid, Pia mater.
34
Sub-arachnoid space significance?
Located between arachnoid and pia mater, contains CSF for cushioning and protection.
35
Role of superior sagittal sinus?
Venous sinus that drains blood and CSF from the brain.
36
Arachnoid granulations and CSF absorption?
Projections that absorb CSF into the superior sagittal sinus.
37
CSF production and absorption?
Produced in brain ventricles and absorbed through arachnoid granulations into the bloodstream.
38
Dura Mater features and head injuries?
Outermost layer, crucial for protecting the brain during head injuries.
39
Consequences of Middle Meningeal Artery rupture?
Risk of extradural hematoma, leading to increased intracranial pressure.
40
Emergency intervention for head injury?
Drainage of hematoma is critical to relieve pressure on the brain.
41
Key structures formed by dura mater?
Falx Cerebri: Separates cerebral hemispheres.Tentorium Cerebelli: Separates cerebrum from cerebellum.
42
Color-coded regions of cranial cavity?
Red: Anterior cranial fossa.Purple: Middle cranial fossa.
43
Anatomical structures in cranial cavity?
Base of the skull revealed after brain removal, showing foramina for nerve passage.
44
Significance of foramina in the skull?
Allow passage of cranial nerves and blood vessels.
45
Functions of cranial nerves?
Cranial Nerve I: Smell.Cranial Nerve II: Vision.
46
Cranial nerves exit points?
12 pairs exit through foramina in the skull.
47
Roles of mandibular and maxillary nerves?
Mandibular: Innervates muscles of mastication and sensation to the jaw.Maxillary: Supplies sensation to the upper teeth and face.
48
Cranial nerves for eye movement?
Cranial Nerve III: Oculomotor, controls most eye movements.
49
Significance of cranial nerve XII?
Supplies motor function to the tongue, essential for speech and swallowing.
50
Cranial nerves for sensory functions?
Cranial Nerve V: Provides sensory innervation to the face.
51
Cranial nerves associated with the ear?
Cranial Nerve VII: Supplies sensory and motor functions to the ear.
52
Main functions of cranial nerves IX, X, and XI?
Cranial Nerve IX: Taste and swallowing.Cranial Nerve X: Controls heart rate and digestion.Cranial Nerve XI: Controls neck and shoulder movements.
53
Arachnoid layer features?
Shiny covering of the brain, providing a protective layer.
54
Rupture of cerebral arteries?
Blood accumulates in the subarachnoid space, leading to hemorrhagic stroke.
55
Arterial pulsation and CSF movement?
Helps move CSF to the superior sagittal sinus, aiding in circulation.
56
Types of hematomas?
Extradural: Occurs outside the dura mater.Subdural: Caused by ruptured veins beneath the dura.
57
Significance of subarachnoid space?
Contains CSF, providing cushioning and protection for the brain.
58
Types of artery ruptures in strokes?
Large arteries: Often linked to aneurysms and hemorrhagic strokes.
59
Major sulci of the brain?
Central Sulcus: Divides the frontal and parietal lobes.
60
Brain structure organization?
Divided into lobes, with gyri (ridges) and sulci (grooves) for increased surface area.
61
Functional significance of brain lobes?
Each lobe has distinct functional areas for processing different types of information.
62
Main areas for motor and sensory functions?
Motor Area: Located in the frontal lobe, responsible for voluntary movement.Sensory Area: Located in the parietal lobe, processes sensory information.
63
Damage to brain areas?
Motor problems: Typically occur in areas anterior to the central sulcus.
64
Exploration of brain structure?
Involves understanding individual gyri and their specific functions.
65
Types of gyrus in the brain?
Various types exist, each associated with different functions.
66
Structures at the base of the brain?
Brainstem and cerebellum: Critical for basic life functions and coordination.
67
Significance of gyrus?
Crucial for increasing the surface area of the brain, allowing for more neurons.
68
Memorizing types of gyrus?
No need to memorize specific types at this stage.
69
Key structures in sagittal brain section?
Corpus Callosum: Connects the left and right cerebral hemispheres.
70
Significance of labeled structures?
Helps in identifying and understanding the functions of different brain lobes.
71
Role of Corpus Callosum?
Facilitates communication between the two cerebral hemispheres.
72
Function of Thalamus?
Acts as a relay station for sensory information before it reaches the cortex.
73
Feature between thalami?
Third ventricle: Contains CSF and circulates it around the brain.
74
Significance of lateral ventricle?
Contains CSF, providing cushioning for the brain.
75
Features of ventricular system?
Located inside the cerebrum, connected by Foramen of Monro for CSF flow.
76
CSF flow path in the brain?
Lateral ventricles → Foramen of Monro → Third ventricle → Aqueduct of Sylvius.
77
CSF production site?
Produced in the lateral, third, and fourth ventricles of the brain.
78
Structures in CSF flow?
Foramen of Monro connects the lateral and third ventricles.
79
Significance of septum pellucidum?
Thin membrane that separates the lateral ventricles.
80
Fourth ventricle and spinal cord?
Located behind the pons and medulla, connects to the central canal of the spinal cord.
81
Key structures in the brain?
Medulla, Pons, Midbrain: Essential for various brain functions.
82
Importance of identifying brain structures?
Crucial for understanding brain anatomy and functions.
83
Identification process of brain structures?
Utilizes various methods for easier identification.
84
Objective of identification focus?
Know how to identify key structures and their functions.
85
Main structures of the cerebellum?
Two hemispheres connected by the vermis, involved in coordination.
86
Cerebellar peduncles and functions?
Superior: Connects to midbrain; Middle: Connects to pons; Inferior: Connects to medulla.
87
CSF production sites?
Third, fourth, and lateral ventricles produce CSF.
88
Roof of fourth ventricle?
Covered by cerebellum and pia mater, providing protection.
89
Openings for CSF movement?
Foramen of Magendie and Foramen of Luschka allow CSF to exit the fourth ventricle.
90
CSF movement to subarachnoid space?
Exits through openings in the fourth ventricle into the subarachnoid space.
91
Foramina in CSF flow?
Foramen of Magendie and Foramen of Luschka facilitate CSF flow.
92
CSF absorption process?
Pulsatile vessels move CSF to the brain for absorption.
93
Sequence of CSF production and flow?
1. Production in Lateral Ventricles.2. Flow through Foramen of Monro.
94
CSF travel through brain ventricles?
3. Enters third ventricle.4. Progresses through Aqueduct of Sylvius.
95
CSF after fourth ventricle?
5. Reaches fourth ventricle.
96
CSF exit points from fourth ventricle?
Median Aperture and two Lateral Apertures allow CSF to exit.
97
CSF flow into subarachnoid space?
Exits through openings in the fourth ventricle into the subarachnoid space.
98
Arachnoid granulations and CSF absorption?
Absorb CSF into the superior sagittal sinus for drainage.
99
Superior sagittal sinus function?
Venous channel for drained CSF and blood from the brain.
100
Functions of CSF in CNS?
Provides buoyancy, cushioning, and nutrient transport for the brain.
101
CSF interaction with spinal cord?
Descends into the central canal of the spinal cord.
102
CSF movement and absorption pathways?
Passes through foramens and is absorbed into the superior sagittal sinus.
103
Meningitis and diagnosis?
Infection causing inflammation of the meninges; diagnosed via CSF sample.
104
Types of fibers in the brain?
Short association fibers: Connect nearby areas; Long association fibers: Connect distant areas; Commissural fibers: Connect hemispheres.
105
Types of projection fibers?
Ascending: Carry sensory information; Descending: Carry motor commands.
106
Motor and sensory areas relative to central sulcus?
Motor: Located in front of the central sulcus; Sensory: Located behind the central sulcus.
107
Main topics in upcoming weeks?
Focus on sensory and motor control mechanisms.
108
First half of upcoming block?
Majority will cover sensory systems and their functions.
109
Transition after initial weeks?
Shift focus to higher mental functions and cognitive processes.
110
Weeks 6, 7, and 8 topics?
Higher mental functions, including memory and learning.
111
Final week of block?
Focus on infections related to the brain and their implications.
112
Main segments of the spinal cord?
Cervical, thoracic, lumbar, sacral, coccygeal segments.
113
Spinal cord start and end in adults?
Begins at foramen magnum and ends at L1/L2 vertebrae.
114
Spinal nerves exit the spinal cord?
Each segment produces a pair of spinal nerves that exit through intervertebral foramina.
115
Spinal cord segment alignment with vertebral levels?
Misalignment can lead to diagnostic confusion and complications.
116
Cauda equina features?
Bundle of spinal nerves that exit below L5, resembling a horse's tail.
117
Dura and arachnoid layers in spinal taps?
Continue until S2; taps are performed at L3/L4 or L4/L5 levels.
118
Spinal cord termination in infants vs adults?
Ends at L3 in infants, while in adults it ends at L1/L2.
119
Spinal cord and meninges relationship?
Spinal cord is covered by meninges, with CSF in the subarachnoid space for protection.
120
Extent of spinal cord in vertebral column?
Extends from foramen magnum to L1/L2 in adults.
121
First week of block significance?
Establishes a framework for understanding the nervous system's structure and function.
122
Topics in first week of nervous system development?
Focus on early development stages of the nervous system.
123
Transcription and review of content?
Transcribed by Raghda Adwan and reviewed by Aiko Danish.
124
Significance of new terms in first week?
Foundational for understanding complex concepts in neuroscience.
125
Key components in neurulation?
Neural plate, notochord, and neural crest cells are essential for development.
126
Main brain vesicles?
Crucial for classifying brain structures during development.
127
Neural tube defects (NTDs) importance?
Essential for understanding prevention and etiology of developmental disorders.
128
Three important concepts in lecture?
Neurulation, brain vesicles, and neural tube defects.
129
Brain vesicles and structure development?
Foundation for brain classification and organization.
130
Primary germ layers significance?
Ectoderm: Forms the nervous system and skin.
131
Embryonic development timeline?
Week 1: Fertilization and initial cell divisions.
132
Germ layers and nervous system development?
The entire nervous system develops from the ectoderm layer.
133
Colors for germ layers in textbooks?
Blue: Ectoderm; Red: Mesoderm; Yellow: Endoderm.
134
Organ systems development timeline?
Most organ systems begin developing in week 4 of gestation.
135
Neural plate significance?
Initial appearance of the nervous system during embryonic development.
136
Neural plate induction?
Induced by the sonic hedgehog (SHH) gene, crucial for neural development.
137
Notochord role in CNS development?
Crucial for the development of the central nervous system.
138
Notochord characteristics?
Rod-like structure in the mesoderm that provides support during development.
139
Ectoderm above notochord under SHH?
Becomes the neural plate, initiating CNS development.
140
Notochord location during development?
Located in the midline of the embryonic disk, providing structural support.
141
Notochord functions?
Induces ectoderm differentiation into neural tissue.
142
Structures from notochord?
Forms the nucleus pulposus of intervertebral discs.
143
Parts of intervertebral disks?
Annulus Fibrosus: Outer layer; Nucleus Pulposus: Inner gel-like core.
144
Remains of notochord in adults?
Nucleus pulposus in intervertebral discs is a remnant of the notochord.
145
Notochord influence on bony structures?
Initiates the formation of vertebral bodies during development.
146
Key stages of neurulation?
Neural groove formation and closure to form the neural tube.
147
Consequences of neurulation failure?
Can lead to developmental disorders such as spina bifida.
148
Structures from neural canal?
Forms the brain ventricles and central canal of the spinal cord.
149
Neural crest cells significance?
Migrate to form multiple body systems, including the peripheral nervous system.
150
Neurulation timeline?
Occurs between days 20-28 of embryonic development.
151
Neurulation initiation?
Begins with the thickening of the neural plate.
152
Neural tube formation?
Neural groove deepens and closes to form the neural tube.
153
SHH protein role in neurulation?
Stimulates growth of the neural ectoderm, essential for CNS development.
154
Consequences of neurulation failure?
Can lead to embryonic death or severe developmental disorders.
155
Neural tube structure and function?
Tube with a central canal that develops into the brain and spinal cord.
156
Future structures from neural tube?
Develops into the brain and spinal cord, central components of the CNS.
157
Neural tube features?
Curved structure with neuropores that close during development.
158
Directional terms for neural tube?
Caudal: tail end; rostral: head end, important for orientation.
159
Parts of neural tube developing into brain and spinal cord?
Cranial 2/3: Develops into the brain; Caudal 1/3: Develops into the spinal cord.
160
Primary vesicles from neural tube?
Prosencephalon, Mesencephalon, Rhombencephalon: Key for brain structure development.
161
Dorsal vs ventral in brain and spinal cord?
Dorsal: Superior in the brain, posterior in the spinal cord; Ventral: Inferior in both.
162
Caudal and rostral significance in embryology?
Caudal: Towards the tail; Rostral: Towards the head, important for developmental orientation.
163
Neural crest cells characteristics?
Form at the margins of the neural plate and migrate to various locations.
164
Dorsal and ventral in anatomical positioning?
Dorsal: Superior; Ventral: Inferior, crucial for anatomical orientation.
165
Consequences of neural crest cell migration failure?
Can lead to cardiac, craniofacial, or neurological defects.
166
Neurons from neural crest cells?
Form primary sensory neurons and postganglionic autonomic neurons.
167
Neural crest cell origin?
Derived from the neural folds of the neural tube during development.
168
Main derivatives of neural crest cells?
All neural ganglia, adrenal medulla, and Schwann cells.
169
PNS neurons from neural crest cells?
Form dorsal root ganglia and autonomic ganglia in the peripheral nervous system.
170
Neural crest cells in nervous system structure?
Contribute to the formation of neurons and supportive structures in the PNS.
171
Nuclei vs ganglia?
Nuclei: Clusters of neuron cell bodies in the CNS; Ganglia: Clusters in the PNS.
172
Example of a ganglion?
Dorsal root ganglia (DRG): Contains sensory neuron cell bodies.
173
Embryological origin of CNS neurons?
Derived from the neural tube during embryonic development.
174
Adrenal medulla characteristics?
Produces epinephrine, a key stress hormone involved in the fight-or-flight response.
175
Schwann cells role?
Myelinate peripheral nerves, facilitating faster signal transmission.
176
Melanocytes function?
Produce melanin for skin pigmentation and protection against UV radiation.
177
Leptomeninges significance?
Protect the CNS and are derived from neural crest cells.
178
Hirschsprung disease characteristics?
Absence of ganglia in the large intestine, leading to bowel obstruction.
179
Hirschsprung disease cause?
Caused by RET gene mutation affecting neural crest cell migration.
180
Parasympathetic innervation in Hirschsprung disease?
Absence leads to peristalsis issues and bowel obstruction.
181
RET gene significance in Hirschsprung disease?
Regulates neural crest cell migration; mutations can lead to Hirschsprung disease.
182
Clinical sign of Hirschsprung disease?
Absence of meconium passage within the first 48 hours after birth.
183
Sympathetic innervation in Hirschsprung disease?
Promotes constriction of the affected colon segment, worsening obstruction.
184
Treatment for Hirschsprung disease?
Surgical removal of the affected segment of the intestine is necessary.
185
Constipation in Hirschsprung disease?
Due to the affected segment of the intestine not functioning properly.
186
Affected segment in Hirschsprung disease over time?
Enlarges, preventing stool passage and leading to severe complications.
187
Neural tube differentiation components?
Develops into the CNS, including the brain and spinal cord.
188
Structures from neural tube cavity?
Forms the central canal and ventricular system of the brain.
189
Cells lining neural tube?
Neuroepithelial cells: Precursors to neurons and glial cells.
190
Spinal cord relation to brain?
Direct continuation of the brain, with no gap between them.
191
Neuroepithelial cells significance?
Serve as precursors to neurons and glial cells during development.
192
Closure stages of neural tube?
Middle closes first, cranial next, and caudal last during development.
193
Consequences of cranial neuropore failure?
Can lead to encephalocele or anencephaly, severe neural tube defects.
194
Caudal neuropore closure failure?
Leads to spina bifida, a defect in the spinal column.
195
Neuropore closure timeline?
Middle: day 22; cranial: day 25; caudal: day 27 of embryonic development.
196
Neural tube defects from neuropore closure failure?
Anterior: Encephalocele/anencephaly; Posterior: Spina bifida.
197
Neural tube closure progress?
Starts in the middle and extends cranially and caudally.
198
SHH roles in neural tube development?
Induces floor and basal plate formation, crucial for CNS structure.
199
Basal plate structures?
Contains motor neurons and preganglionic autonomic neurons.
200
Sulcus limitans significance?
Separates the alar and basal plates in the developing neural tube.
201
Neural tube cross-section components?
Includes the central canal, neuroepithelial cells, floor plate, and basal plate.
202
Notochord influence on neural tube?
Expresses SHH, essential for basal plate formation and neural development.
203
Ectoderm and neural tube relationship?
Ectoderm forms the skin above the neural tube, providing protection.
204
Dorsal vs ventral in neural tube?
Basal plate: Motor functions; Alar plate: Sensory functions.
205
Neurons from basal plate?
Develop into motor neurons and preganglionic autonomic neurons.
206
Motor neurons influenced by SHH?
Lower motor neurons in the spinal cord are influenced by SHH signaling.
207
Motor neuron development under SHH?
SHH influences the development of lower motor neurons in the spinal cord.
208
SHH role in motor neuron development?
Essential for the differentiation of lower motor neurons in the spinal cord.
209
BMPs in dorsal neural tube development?
Induce roof and alar plate formation, critical for sensory neuron development.
210
Dorsal neural tube structures from BMPs?
Includes the roof plate and alar plate, important for sensory processing.
211
First vs second order sensory neurons?
First: Located in DRG; Second: Transmit sensory information to the CNS.
212
BMPs and sensory neuron development?
Differentiate into second-order sensory neurons for processing sensory information.
213
Roof plate significance?
Organizes the dorsal neural tube and influences sensory neuron development.
214
Primary brain vesicles?
Prosencephalon, Mesencephalon, Rhombencephalon: Key for brain structure development.
215
Secondary brain vesicles?
Telencephalon, Diencephalon, Mesencephalon, Metencephalon, Myelencephalon: Develop from primary vesicles.
216
Primary vesicles split timeline?
Occurs at week 5 of embryonic development.
217
Prosencephalon during secondary vesicle formation?
Splits into Telencephalon and Diencephalon, forming major brain regions.
218
Mesencephalon significance?
Remains unchanged during secondary vesicle formation, serving as a key brain region.
219
Final brain vesicles?
Telencephalon, Diencephalon, Mesencephalon, Metencephalon, Myelencephalon: Final structures of the brain.
220
Importance of memorizing brain vesicle names?
Essential for classifying brain structures and understanding their functions.
221
Telencephalic structure example?
Corpus callosum: Connects the left and right cerebral hemispheres.
222
Primary brain vesicles and derivatives?
3 primary vesicles give rise to 5 secondary vesicles during development.
223
Major CNS components?
6 components, with 5 derived from secondary vesicles.
224
Telencephalon development?
Forms two cerebral hemispheres, responsible for higher cognitive functions.
225
Diencephalon structures?
Includes the thalamus and hypothalamus, critical for sensory and autonomic functions.
226
Rhombencephalon components?
Divides into metencephalon and myelencephalon, forming pons, cerebellum, and medulla.
227
Main derivatives of telencephalon?
Cerebral hemispheres and basal ganglia, involved in movement and cognition.
228
Diencephalon structures?
Thalamus and hypothalamus, key for sensory processing and homeostasis.
229
Cerebral aqueduct function?
Communicates between the third and fourth ventricles, allowing CSF flow.
230
Mesencephalon components?
Midbrain remains unchanged, involved in vision and hearing.
231
Significance of lateral ventricles?
Cavities formed from the telencephalon, containing CSF for brain protection.
232
Vital brain communication parts?
Thalamus and hypothalamus: Key for sensory relay and autonomic control.
233
Fourth ventricle association?
Common cavity for metencephalon and myelencephalon, containing CSF.
234
Structures from metencephalon and myelencephalon?
Metencephalon: Pons and cerebellum; Myelencephalon: Medulla oblongata.
235
Open neural tube defects characteristics?
Neural folds fail to close, leading to severe developmental issues.
236
Alpha-fetoprotein and neural tube defects?
Elevated levels may indicate the presence of neural tube defects.
237
Common congenital malformations with NTDs?
Abnormalities in skull or vertebrae, often associated with NTDs.
238
Imaging for neural tube defects?
Ultrasound effectively visualizes defects during pregnancy.
239
NTDs and mesoderm relationship?
Can lead to bone abnormalities and other structural defects.
240
Craniorachischisis totalis characteristics?
Open brain and spinal cord defect, most severe form of NTD.
241
Craniorachischisis totalis significance?
Incompatible with life due to severe structural defects.
242
Craniorachischisis totalis implications?
Failure in neural tube closure during early development.
243
Anencephaly characteristics?
Failure of cranial neuropore closure, leading to absence of major brain structures.
244
Anencephaly complications during pregnancy?
Elevated alpha-fetoprotein levels may indicate the condition.
245
Anencephaly and amniotic fluid levels?
Excess fluid due to lack of swallowing by the fetus.
246
Ultrasound findings in anencephaly?
Large amniotic fluid volume and small fetal size are common findings.
247
Alpha-fetoprotein in diagnosing anencephaly?
Elevated levels indicate the presence of anencephaly.
248
Structural brain abnormalities in anencephaly?
Absence of brain structures, leading to severe neurological deficits.
249
Encephalocele characteristics?
Meninges and brain herniate through a skull defect, forming a sac.
250
Encephalocele key characteristics?
Herniation of brain tissue through the skull, often requiring surgical intervention.
251
Regions for encephaloceles?
Commonly occur in occipital and frontal regions of the skull.
252
Brain in encephalocele?
Part of the brain protrudes outside the skull, leading to complications.
253
Spina bifida occulta characteristics?
Closed defect with normal alpha-fetoprotein levels, often asymptomatic.
254
Most common spina bifida form?
Spina bifida occulta is the most common type.
255
Detecting spina bifida occulta?
Often undetected unless a tuft of hair or other signs are present.
256
Implications of spina bifida occulta for newborn?
Typically no neurological deficits, allowing for a normal life.
257
Caudal neuropore in spina bifida occulta?
Closes normally, preventing severe defects.
258
Spina bifida cystica with meningocele characteristics?
Cyst-like protrusion through the defect, containing meninges.
259
'Cystica' in spina bifida cystica?
Indicates a bulging structure containing cerebrospinal fluid.
260
Types of spina bifida cystica?
Meningocele and Meningomyelocele are the two main types.
261
Significance of meningocele?
No neurological deficit, but carries a risk of infection.
262
Risks with meningocele?
Higher risk of infection due to exposure of the cyst.
263
Spina bifida cystica with meningomyelocele characteristics?
Most common form, with the spinal cord displaced into the cyst.
264
Neurological issues in meningomyelocele?
Deficits in lower limbs due to spinal cord involvement.
265
'Meningomyelocele' meaning?
Cyst containing both meninges and spinal cord tissue.
266
Why is meningomyelocele severe?
Displaced spinal cord may not function properly, leading to significant deficits.
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Spinal cord control for lower limbs?
Cauda equina controls lower limb function and sensation.
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Factors increasing NTD risk?
Valproic acid, hypothermia, and excessive Vitamin A during pregnancy.
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Preventing NTDs?
Folic acid supplements significantly reduce the incidence of neural tube defects.
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Folic acid role in preventing NTDs?
Crucial for DNA synthesis and repair during early pregnancy.
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Excessive Vitamin A during pregnancy?
Can lead to neural tube defects and other developmental issues.
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Hyaluronic acid significance?
Supports neuroepithelial cell function and promotes tissue hydration.
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Recommended neuroscience textbooks?
Essential Neuroscience, Neuroscience Ed., Fundamental Neuroscience are highly recommended.
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USMLE Step 1 preparation resources?
First Aid for USMLE Step 1, Kaplan Medical's Lecture Notes are useful resources.
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Neuroanatomy and clinical applications books?
Neuroanatomy in Clinical Context, BRS Neuroanatomy are recommended for clinical applications.
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Basic Clinical Neuroscience editions?
Basic Clinical Neuroscience, Fundamental Neuroscience are essential for foundational knowledge.
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Cellular composition of the nervous system?
Types of cells: Neurons and glial cells, each with distinct functions.
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If slides not covered in class?
Review remaining slides independently to ensure understanding.
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Professor mentioned in content?
Volodymyr Mavrych, MD, PhD, DSc is the professor referenced.
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Significance of slides in content?
Provide detailed information on nervous system composition and functions.
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Transcription and review of content?
Transcribed by Hafsah Khalifey, reviewed by Serina for accuracy.
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Learning objectives of neuron lecture?
Understand different types of neurons and their functions in the nervous system.
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Types of neurons?
Pseudounipolar, bipolar, and multipolar neurons, each serving different roles.
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Sensory neurons types?
Pseudounipolar and bipolar neurons are primarily sensory neurons.
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Bipolar neurons locations?
Found in the retina, vestibular ganglia, and spiral ganglia.
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Multipolar neurons types?
Include motor neurons, sympathetic, and parasympathetic neurons.
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Two main glial cell categories?
Macroglia and microglia, each with distinct functions in the nervous system.
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Macroglia types?
Astrocytes and oligodendrocytes are the main types of macroglia.
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Ependyma cells function?
Line the ventricles and produce cerebrospinal fluid (CSF).
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Schwann cells origin?
Peripheral glial cells derived from neural crest cells during development.
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Astrocytes role?
Support neurons and maintain the blood-brain barrier for CNS protection.
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Microglia vs macroglia?
Microglia: Fewer in number, act as immune cells; Macroglia: More numerous, provide support.
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Histological techniques for neurons?
Golgi method, Nissl stain, and Weigert method are used for studying neuronal structures.
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Golgi method use?
Used to study the branching patterns of neurons in detail.
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Nissl stain primary use?
Highlights structures involved in protein synthesis, such as ribosomes and rough ER.
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Weigert method in demyelination?
Stains myelinated axons black, useful for studying demyelination.
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Golgi method limitations?
Shows a limited number of neurons, making it difficult to generalize findings.
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Nissl stain highlights?
Highlights the nucleus, cell body, and ribosomes of neurons.
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Weigert method significance?
Stains myelinated axons to study their integrity and function.
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Neuron types and characteristics?
Bipolar: Single axon and dendrite; Pseudounipolar: One axon with two branches; Multipolar: Multiple dendrites and one axon.
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What are the main functions of neurons in the nervous system?
Neurons are the anatomical and functional units of the nervous system.They receive impulses from receptor organs and transmit them to other neurons or effector organs.
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What is the structure of a neuron?
A neuron consists of a cell body, dendrites, and a single axon.Neurons have mostly lost the capacity to undergo cell division.
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How many neurons are estimated to be in the human brain?
The human brain contains approximately 86 billion neurons.It also contains about 85 billion glial cells.
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What are the main components found in the cell body of a neuron?
The nucleusMembrane-bound cytoplasmic organelles such as endoplasmic reticulum, Golgi apparatus, mitochondria, and lysosomes
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What are the two main processes of a neuron and their functions?
Axon: Conducts impulses away from the cell bodyDendrites: Specialized to receive information and conduct it to the cell body
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How does the size of the axon compare to the neuronal cell body?
The axon is thousands of times more voluminous than the neuronal cell bodyThis allows for efficient transmission of impulses over long distances
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What is the role of dendrites in a neuron?
Dendrites are processes that receive information from other neuronsThey conduct this information to the cell body for processing
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What are the key functions and structures associated with the nucleus in a cell?
The nucleus contains DNA and is the site of RNA synthesis.It has a double-layered nuclear membrane with fine pores.Chromatin, which includes euchromatin (active) and heterochromatin (inactive), is found within the nucleus.
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What is a Barr body and its significance in female cells?
A Barr body is the inactive copy of an X chromosome in female cells.It is present in the nucleus and represents one of the two X chromosomes.
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What are the differences between euchromatin and heterochromatin?
Euchromatin is the active, homogenous portion of the genome.Heterochromatin is tightly packed and represents the inactive form of DNA.
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What role does the nucleolus play in the cell?
The nucleolus is responsible for the synthesis of ribonucleic acid (RNA).It is a prominent structure found within the nucleus.
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How does the structure of the nuclear membrane contribute to its function?
The nuclear membrane is double-layered, providing a barrier and compartmentalization for the nucleus.It contains fine pores that allow selective transport of molecules in and out of the nucleus.
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Why are the nucleus and nucleolus particularly prominent in neurons?
Neurons have high metabolic activity and require significant amounts of RNA for protein synthesis.The nucleus and nucleolus support the production of necessary components for neurotransmission and cellular function.
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What are the characteristics and functions of Rough Endoplasmic Reticulum (RER) in neurons?
RER has ribosomes on its walls, which are essential for protein synthesis.It is present in the cell body and dendrites but absent in the axon and axon hillock.
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What is the significance of Nissl bodies in neurons?
Nissl bodies, or Nissl substance, are large granular bodies found in neurons.They consist of rough endoplasmic reticulum and are the primary site for protein synthesis.
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How are neurotransmitters synthesized in neurons?
Small molecule neurotransmitters, like acetylcholine (Ach), are synthesized in the axonal terminal.Neuropeptides are synthesized in the neuronal cell body and transported to the axonal terminal.
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What is the role of the Golgi apparatus in relation to proteins synthesized in the RER?
Proteins synthesized in the RER are packed and modified in the Golgi apparatus.The Golgi apparatus is crucial for processing and distributing proteins to their final destinations.
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What distinguishes the cytoplasm of the axon from that of the cell body in neurons?
The cytoplasm of the axon lacks free polysomes, Nissl substance, and Golgi apparatus.This difference is important for the unique functions of the axon in signal transmission.
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What are the main functions of the Golgi apparatus in a cell?
Acts as a warehouse for synthesized materials.Modifies proteins through processes like glycosylation and phosphorylation.Packages proteins into vesicles for transport to various intracellular locations.
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How do lysosomes function within neurons?
They are small membrane-bound vesicles formed from the Golgi apparatus.Contain hydrolytic enzymes that help in breaking down waste materials.Serve as scavengers, cleaning up cellular debris in neurons.
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What is the relationship between the Golgi apparatus and the rough endoplasmic reticulum (RER)?
Protein-containing vesicles bud off from the RER.These vesicles are transported to the Golgi apparatus for further processing.The Golgi modifies and packages these proteins for delivery to their destinations.
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What structural features characterize the Golgi apparatus?
Consists of aggregations of flat vesicles of various sizes.Made up of smooth endoplasmic reticulum.Functions in the modification and packaging of proteins.
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What processes occur to proteins in the Golgi apparatus?
Proteins undergo modifications such as glycosylation and phosphorylation.They are then packaged into vesicles for transport.This ensures proteins reach their correct intracellular locations.
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What are Lewy bodies and where are they typically found?
Lewy bodies are eosinophilic cytoplasmic inclusions in degenerating neurons.They are primarily found in the substantia nigra in Parkinson's disease and in cortical neurons in Lewy body dementia.
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What are the effects of Lewy body dementia on patients?
Patients may experience vision problems and visual hallucinations due to involvement of the occipital cortex.Other symptoms can include sleep disturbances and movement disorders.
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What are Negri bodies and their association with diseases?
Negri bodies are eosinophilic cytoplasmic viral inclusions found in degenerating neurons.They are typically associated with rabies and are found in Purkinje cells in the cerebellum and hippocampus.
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How do Lewy bodies differ from Negri bodies in terms of origin?
Lewy bodies are associated with neurodegenerative diseases like Parkinson's and Lewy body dementia.Negri bodies are viral inclusions specifically linked to rabies infection.
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What role does the occipital cortex play in Lewy body dementia?
The occipital cortex is involved in vision processing.Damage or degeneration in this area can lead to visual hallucinations in patients with Lewy body dementia.
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What are the common locations for Lewy bodies in the brain?
Commonly found in the substantia nigra in the midbrain for Parkinson's disease.Also found in the cortical neurons, particularly in the occipital cortex for Lewy body dementia.
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What are the key characteristics of mitochondria?
Mitochondria have their own DNA.They are inherited only from maternal cells.They are spherical or rod-shaped structures.They consist of a double membrane.
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What is the role of mitochondria in energy production?
Mitochondria generate ATP, the energy currency of the cell.They require glucose (in the form of pyruvate) and oxygen to produce ATP.They are involved in aerobic oxidation processes.
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What happens to ATP production during starvation and lack of oxygen?
In starvation, there is a lack of glucose, leading to reduced ATP production.If there is a lack of oxygen, ATP production ceases entirely.
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How do mitochondria contribute to the process of aerobic oxidation?
Pyruvate from glycolysis is transported into mitochondria for oxidation.Oxygen is used to convert pyruvate into carbon dioxide, generating ATP.34 out of 36 ATP molecules are produced in this process.
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Where are mitochondria located within a neuron?
Mitochondria are present in the body of the neuron.They are also found in dendrites and the axon of the neuron.
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What is anoxia and how does it affect survival?
Anoxia is the lack of oxygen.Humans can survive without oxygen for a maximum of 5 minutes before neuronal cells get severely damaged and die.
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What role does ATP play in neuronal function?
ATP is the energy currency of the cell, fueling biochemical reactions in neurons.Without ATP, the sodium-potassium pump cannot function, leading to a loss of resting membrane potential.
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How does the sodium-potassium pump maintain resting membrane potential?
The pump moves 3 Na+ ions out of the cell and 2 K+ ions into the cell.This creates a higher negative charge inside the cell, establishing the resting membrane potential (RMP).
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What happens to the sodium-potassium pump in the absence of oxygen?
Without oxygen, ATP production ceases, and the sodium-potassium pump cannot function.This results in equal concentrations of Na+ and K+ on both sides of the membrane, eliminating resting membrane potential.
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What is the consequence of losing resting membrane potential in neurons?
Without resting membrane potential, action potentials cannot occur.This leads to a failure of neuronal communication and brain function.
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Why do we have a negative resting membrane potential (RMP)?
The RMP is negative because 3 positive Na+ ions are pumped out for every 2 positive K+ ions pumped in.This results in a higher concentration of positive ions outside the cell compared to the inside, creating a negative charge within the cell.
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What are the main functions of microtubules in neurons?
Provide structural support and shape to the neuron.Facilitate intracellular transport of vesicles through anterograde and retrograde directions.
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What are the key components of microtubules?
Microtubules are made up of helical cylinders consisting of 13 protofilaments.Each protofilament is assembled from alpha- and beta-tubulin subunits.
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How do microtubules align in axons?
Microtubules align with their '+' ends directed away from the soma.Accessory proteins, known as MAPs, help in the proper alignment of microtubules.
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What roles do kinesin and dynein play in microtubule transport?
Kinesin translocates vesicles toward the '+' ends of microtubules (fast anterograde transport).Dynein moves vesicles toward the '-' ends of microtubules (retrograde transport).
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What are microtubule-associated proteins (MAPs)?
MAPs are proteins that regulate the assembly and function of microtubules.They help maintain the structural integrity and alignment of microtubules in neurons.
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What are the main uses of vincristine in cancer treatment?
Used to treat several types of cancer including acute leukemia.Effective for Hodgkin's disease, neuroblastoma, and small-cell lung cancer.
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How does vincristine work at the cellular level?
It binds to the tubulin protein, disrupting microtubule assemblies.This prevents spindle formation, stopping chromosome separation during metaphase.
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What is the primary side effect of vincristine?
Induced peripheral neuropathy affecting the longest peripheral nerves.Results in glove-and-stock pattern neuropathy in fingers and toes.
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Why does vincristine not affect the central nervous system?
It does not cross the blood-brain barrier.This limits its effects to peripheral nerves only.
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What distinguishes cancer cells from normal cells?
Cancer cells divide uncontrollably and continuously.Normal cells have regulated division processes.
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What is the role of Tau protein in neurons?
Tau protein assembles and stabilizes microtubules by binding to their surface.It acts as a bridge in axons, ensuring microtubules run straight and parallel.
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How do neurodegenerative disorders affect Tau proteins?
In neurodegenerative diseases, Tau proteins can become excessively phosphorylated.This phosphorylation prevents Tau from cross-linking microtubules, leading to their detachment and accumulation in the soma.
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What happens to microtubules when Tau protein is dysfunctional?
Dysfunctional Tau leads to the formation of helical filaments in microtubules.This progression results in neurofibrillary tangles, which are characteristic of certain neurodegenerative diseases.
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What is the significance of Tau protein in microtubule assembly?
Tau promotes the self-assembly of microtubules from tubulin subunits.It stabilizes the structure of microtubules, which is crucial for neuronal function.
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What are the primary areas of the brain affected by Alzheimer's disease?
Neurons in the limbic systemCholinergic neurons in the basal nucleus of MeynertNeurons in the cerebral cortex
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What are the prominent features of degenerating neurons in Alzheimer's disease?
Neurofibrillary tanglesDegeneration of neurons in specific brain regions
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What is the most common cause of dementia?
Alzheimer's diseaseIt primarily affects neurons in the basal nucleus of Meynert and the cerebral cortex
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Which other conditions exhibit neurofibrillary tangles similar to Alzheimer's disease?
Amyotrophic lateral sclerosisDown syndrome
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What type of neurons are primarily affected in Alzheimer's disease?
Cholinergic neurons in the basal nucleus of MeynertNeurons in the cerebral cortex and limbic system
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Who was the first to describe Alzheimer's disease and what are its key characteristics?
Aloysius Alzheimer was the first to describe this disorder.Alzheimer's disease typically affects patients around 65 years of age and progresses slowly over approximately 10 years.
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What are the classical signs and symptoms of Alzheimer's disease?
Gradual onset and progressive memory loss.Mood alterations, disorientation, aphasia, and apraxia, leading to a bedridden state and eventual death.
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What is the pathophysiology of Alzheimer's disease?
An abnormal protein is synthesized instead of the normal protein, leading to the formation of amyloid plaques.These plaques cause hyperphosphorylation of Tau proteins, resulting in neurofibrillary tangles and neuron death.
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What percentage of dementia cases does Alzheimer's disease account for and how does incidence change with age?
Alzheimer's disease accounts for 60% of all cases of dementia.The incidence of Alzheimer's disease increases with age.
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What are the hereditary aspects of Alzheimer's disease?
5% - 10% of cases are hereditary and classified as early onset.These cases are transmitted as an autosomal dominant trait.
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What are the key pathological features of Alzheimer's disease?
Involves amyloid beta (Aβ) 42-residue peptide and abnormal tau proteins.Lesions affect the neocortex, hippocampus, and cholinergic nuclei in the forebrain.
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What are senile plaques and neurofibrillary tangles in the context of Alzheimer's disease?
Senile plaques consist of a core of Aβ amyloid surrounded by microglia and astrocytes.Neurofibrillary tangles are intraneuronal aggregates of insoluble phosphorylated tau.
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What are the key gross and microanatomical changes associated with Alzheimer's disease?
Brain tissue shrinkage and cortical atrophy.Formation of amyloid plaques and neurofibrillary tangles.
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What is Hydrocephalus ex vacuo and how is it related to Alzheimer's disease?
It results from the degeneration of cortical and cholinergic neurons.It is associated with significant loss of choline acetyltransferase in the cerebral cortex.
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What is the significance of the Nucleus of Meynert in Alzheimer's disease?
It is involved in the degeneration of cholinergic neurons.Its degeneration contributes to cognitive decline in Alzheimer's patients.
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What percentage of choline acetyltransferase loss is observed in the cerebral cortex of Alzheimer's patients?
60% to 90% loss is typically observed.This loss is linked to cognitive impairments in Alzheimer's disease.
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What visual changes can be observed in the brain of an Alzheimer's patient?
Shrinking of brain tissue and formation of small gyra.Presence of plaques and tangles in brain images.
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Why is it recommended to watch videos about Alzheimer's disease?
Videos can provide visual and detailed explanations of the disease.They help in understanding the complexities of Alzheimer's pathology.
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What are the key findings in CNS neurons during an autopsy of a patient with Alzheimer's disease?
Neurofibrillary tangles, which are aggregates of hyperphosphorylated tau protein.Possible presence of plaques near the surfaces of the lateral and fourth ventricles, indicating amyloid-beta accumulation.
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What are the main functions of neurofilaments in neurons?
Provide structural support for axons.Regulate axon diameter, influencing nerve conduction velocity.
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How do astrocytes contribute to the maintenance of brain shape?
They provide a scaffold for neurons.Synthesize neurofilaments made of glial fibrillary acidic proteins (GFAP) and release them into the extracellular space.
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What role do radial glial cells play in neuronal development?
They serve as precursors for astrocytes.Guide future neurons to their proper locations during development.
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Is neuronal regeneration possible in the central nervous system (CNS)?
No, regeneration is not possible in the CNS.Astrocytes release GFAP, which prevents regeneration in the affected area.
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What are neurofilaments composed of?
Fibers that twist around each other to form coils.Two thin protofilaments form a protofibril, and three protofibrils form a neurofilament about 10 nm in diameter.
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What is the difference between neurofilaments in neurons and filaments in astrocytes?
Neurofilaments in neurons are composed of neurofilament proteins.Astrocytes have vimentin-related filaments made of glial fibrillary acidic protein (GFAP).
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How do GFAP filaments affect neuronal regeneration in adults?
GFAP prevents neuronal regeneration in the CNS.Specific chemical inhibitors released by astrocytes and oligodendrocytes also contribute to this inhibition.
