Keeping People Healthy: Week One Flashcards
1
Q
Name the determinates of health
A
- Income and social status
- Education
- Physical environment
- Social support channels
- Genetic
- Personal behaviour
- Health services
- Gender
2
Q
What are the factors that contribute to the Bradford Hill Criteria?
A
- Strength
- Constituency
- Specificity
- Temporality
- Biological gradient
- Plausibility
- Coherence
- Experiment
- Analogy
3
Q
What does Noggin inactivate?
A
BMP-4
4
Q
Name four threats to validity of a study’s findings
A
- lack of generalising
- chance
- confounding
- bias
5
Q
What part of the cytotrophoblast ensures remodelling of the spiral arteries?
A
Extravilllous
6
Q
How are amino acids transported across the placenta?
A
Active transport
7
Q
What wave was the agent-vector model of disease most prominent?
A
Second
8
Q
What system has the longest critical period of development?
A
Nervous system
9
Q
What system does the drug tetracycline affect?
A
Teeth enamel
10
Q
What system does the drug sodium valproate effect?
A
Neural tube development. This drug is more epilepsy
11
Q
What system does the drug thalidomide effect?
A
Limb development
12
Q
What system does Rubella affect?
A
Ear development
13
Q
Which weeks is the pre-embryonic period?
A
Weeks 1-2
14
Q
Which weeks is the embryonic period?
A
Weeks 3-8
15
Q
Which weeks is the fetal period?
A
Weeks 9- Term
16
Q
Which germ layer forms the notochord?
A
Mesoderm
17
Q
What forms the nucleus fibrosis?
A
Notochord
18
Q
What germ layer gives the neural tube?
A
Ectoderm
19
Q
How many cervical somite pairs are there?
A
8
20
Q
How many thoracic somite pairs are there?
A
12
21
Q
How many lumbar somite pairs are there?
A
5
22
Q
How many sacral somite pairs are there?
A
5
23
Q
How many coccygeal somite pairs are there?
A
8-10
24
Q
What separates the somatic (dorsal layer) and the splanchnic (ventral layer) mesoderm layer?
A
Coelem
25
What two structures form the chorion?
The trophoblast and the extra-embryonic mesoderm.
26
What shape is the placenta?
Discoidal
27
When and how do primary villi form?
Day 14: stalks of cytotrophoblast emerge
28
When and how to secondary villi form?
Extra-embryonic mesoderm invades the core of the primary villi
29
How do tertiary villi form?
Blood vessels develop in the mesenchyme and these will eventually connect with the umbilical vessels.
30
How are amino acids and glucose transported across placenta?
Facilitated diffusion: against concentration gradient
31
What vitamins cross the placenta?
B,C,D
32
How do antibodies cross the placenta?
Pinocytosis
33
Name two viruses that can cross the placenta
HIV, Rubella
34
What layer of the trophoblast produces hormones, including oestradiol and progesterone
Syncytiotrophoblasts
35
What are the features of the early placental barrier?
There is both the syncytiotrophoblasts layer and the cytotrophoblast layer which some blood vessels
36
What are the features of the late placental barrier?
There is no cytotrophoblast. The mesenchyme becomes more dense and the mass of villi and blood vessels increase
37
What are Hafobauer cells?
Placenta macrophages
38
What are placental macrophages called?
Hafobauer cells
39
What does the central nasal prominence become?
Forehead, nose, middle portion of upper lip and primary palate
40
What does the left and right maxillary prominences become?
Lower face regions lower lip, jaw and secondary palate
41
Why is folate essential during pregnancy?
RNA and DNA synthesis
42
Which arteries does maternal blood flow through to reach the intervillus space?
Spiral arteries
43
What is the rate of blood flow during full pregnancy?
500ml/min
44
What are the four extra-embryonic membranes and what is the innermost one?
The amnion, chorion, yolk sac and allantois
| The amnion is the inner one
45
What is the meaning of malformation?
This is a structural defect of part or the whole organ caused by an abnormal process intrinsic to its development. An example is spina bifida
46
What is the meaning of disruption?
This is a defect in an organ or body part caused by a process that interferes with an originally normal developmental process. An example is thalidomide induced Phocomelia.
47
What is the meaning of deformation?
Structural abnormality caused by mechanic fore. An example is amniotic band constriction.
48
What is a sequence?
This is a pattern of multiple malformations stemming form a disturbance of developmental process/mechanical factor. An example is Potter sequence.
49
What is a syndrome?
Group of malformations of differ structures due to a single primary cause, but acting through multiple pathways. An example is Down syndrome
50
What is an association?
Group of anomalies seen in more than one individual that cant be attributed to definitive cause.
51
What is teratology?
Study of abnormal development of congenital defects
52
What is a teratogen?
An agent that disturbs the development of embryo
53
What period is the more susceptible to teratogens?
Weeks 3-8 (embryonic stage)
54
What are the outcomes of a teratogen in weeks 1-2?
Death or embryo can compensate
55
What is the critical period for the Heart?
Weeks 3-6
56
What is the critical period for the CNS?
Weeks 2-7
57
What teratogen can caused hydantoin syndrome and what are some features?
Fetal hydantoin syndrome, also called fetal dilantin syndrome is a group of defects caused to the developing fetus by exposure to teratogenic effects of phenytoin or carbamazepine. Dilantin is the brand name of the drug phenytoin sodium in the United States, commonly used in the treatment of epilepsy.
Effects include prominent eye and increase space between eyes
58
What are the consequences of methotrexate during pregnancy?
Craniofacial abnormalites
59
What affect does alcohol have on pregnancy?
Foetal alcohol syndrome
60
Why is alcohol bad during pregnancy?
The liver cant metabolize the alcohol ad hence the blood becomes highly concetrated
61
What does Rubella cause on the 6th week of development?
Cataracts.
62
What does Rubella cause on the 9th week of development?
Deafness
63
What is raised body temperature during pregnancy associated with?
Anencephaly
64
Explain the Manchester triage system
RED: urgent and patient is seen straight away
ORANGE: this is very urgent and patient is seen in 10 minutes
YELLOW: this is urgent and patient is seen in 60 minutes
GREEN: this is standard and patient is seen in 120 minutes
BLUE: this is non-urgent and patient is seen in 240 minutes
65
Explain the diffusion of oxygen and carbon dioxide in the placenta
This will diffuse due to partial pressure
66
What is the difference with fetal haemoglobin?
The fetal blood have 50% more haemoglobin and this has a higher oxygen affinity.
67
How is glucose transported across the placenta?
Through hexose transporters via facilitated transport that aren't dependent on insulin.
68
How is glucose used in embryo for energy?
Glucose oxidised to lactate and this is used as energy.
69
How doe amino acids cross the placenta?
Active transport
70
What is the only antibody that crosses the placenta?
IgG
71
What is bilirubin?
A waste product of haemoglobin. This is usually conjugated in liver to be water-soluble and then is secreted in bile.
72
What happens to bilirubin in the featus?
Conjugated Bilirubin crosses the placenta poorly. There is therefore only a small portion of conjugated bilirubin produced, most is unconjugated.
73
When does the Morula form?
Day 4
74
When does the blastocoel form?
Day 5
75
What affect does warfarin have during pregnancy?
Bone abnormalities
76
What affect does aspirin have during pregnancy?
Heart abnormalities
77
What affect does sodium valproate have on folate levels?
Decreases it
78
What does the amniotic cavity consist of?
The inner ectoderm layer and outer mesoderm layer.
79
What three parts does a receptor have?
Extracellular part, transmembrane part, intracellular part
80
Where is sonic hedgehog secreted?
Notochord
81
Where does the notochord form and what is it formed of?
This is from the mesoderm and is ventral to ectoderm
82
The signals noggin and chordin, are from the notochord. What are their functions?
These induce neural tube development. These signals will inactivate BMP4. The absence of BMP4 will cause NT patterning and somite formation
83
What does the appearance on the notochord cause the overlying ectoderm to do?
The ectoderm thickens and forms the neural plate. Cells of the plate make up the neuroectoderm. Once the plate is induced, the growing begins. The structure lengthens and the lateral edges elevates, forming the neural folds. The depressed region forms the neural groove. The folds will eventually fuse and form the neural tube.
84
When do anterior pores fuse?
Day 25
85
When do posterior pores fuse?
Day 27
86
What affect does SHH have on the neural tube?
Causes the formation of the neural plate
87
What is anencephaly the result of?
Failure of anterior neuropore closure
88
What are the signals in the upper spine?
There is increased SHH and inhibition by BMP2. There is only the median hinge points and the dorsal lateral hinge points are absent
89
What are the signals in the lower spine?
There is reduced SHH, noggin in uninhibited and this mean BMP2 is inhibited. Only the dorsal hinge points are present.
90
What two membrane proteins does SHH require and what are their roles?
Patched and Smoothened. SHH binds to patched and this removes the original inhibition it caused to smoothened. This regulate downstream pathways.
91
What does SHH require to be activated?
Cholesterol
92
What is the fetal portion of the placenta called?
Villus Chorion
93
What is the maternal portion of the placenta called?
Decidua basalis
94
What vessels are in the umbilical cord?
Two arteries and one vein
95
What are cotyledons?
Lobes of the maternal side of the placenta
96
What does the chorionic plate consist of?
Amnion, extra-embryonic mesoderm, cytotrophoblast and syncytiotrophoblasts
97
What twins are formed at day 1-3?
Dichorionic diamniotic: separate chorionic and amniotic sacs
98
What twins are formed at days 4-8?
Monochorioinic diamniotic: only share chorionic sac
99
What twins are formed at days 8-13?
Monoamniotic: share the amniotic sac
100
What twins are formed during the formed embryo?
Conjoined
101
What does the trophoblast remodel the maternal arteries to?
Low flow - high resistance to High flow - low resistance
102
What is pre-eclampsia diagnosed with?
High blood pressure and protien in the blood (proteinuria)
103
What is pre-eclampsia?
Trophoblast invasion is abnormal
104
When is fetal blood flow establish?
By the end of the 4th week
105
What is the acrosome reaction?
This occurs when the sperm bind to the zona pellucida. The sperm will release enzymes to break he zone pellucida and the sperms protective coat is removed.
106
How does the egg prevent more sperm entering?
Release cortical granules
107
What are blastomeres?
The cell divides in the early stages
108
When does the trophoblast differentiate?
As it makes contact with the endometrium
109
Where does the amniotic cavity form?
Between epiblast and cytotrophoblast
110
How does the exocoelemic membrane form and what is it a part of?
This forms from the hypoblast migrate around the inner membrane of the trophoblast. This membrane, and the hypoblast, forms the primitive yolk sac.
111
What are lacunar networks?
The lacunae will form in the syncytiotrophoblasts and will stop forming at day 12, by which point they fuse and form networks.
112
What do enzymes from the syncytiotrophoblasts break down?
The maternal sinusoids and uterine glands. This allows the secretions to flow into the networks.
113
Where does the extraembryonic mesoderm form?
Between inner cytotrophoblast and outer surface of the yolk sac
114
Where does the chorionic cavity form?
Extraembryonic mesoderm will form large cavities and these will eventually fuse
115
How is the secondary yolk sac formed?
A part of the extra-coelmic membrane is pinched of
116
How is the bilaminar disc connected to the trophoblast?
A band of extraembryonic mesoderm called the connecting stalk. This is the future umbilical cord.
117
How does the primitive streak form?
Around day 15, the epiblast thickens are the caudal end. This defines the major axis of the body.
118
Explain the process of the formation of the primitive node, pit and groove
The primitive streak will expand at the cranial end from the caudal end to create the primitive node. This node has a circular depression known as the primitive pit. The depression continues along the caudal end, forming the primitive groove.
119
Explain the process of invagination and how the three germ layers are formed
Once the primitive groove has been formed, the cells from the epiblast go beneath the groove. This process is called invagination. The first cells to invaginate, invade the hypoblast and displace their cells. These cells will become the endoderm. The remaining cells of the epiblast form the ectoderm.
Some invaginated cells remain between the endoderm an ectoderm and form the mesoderm.
120
Explain the process of neurulation
There is a thickened layer of ecotderm cells to form the neural plate. This forms at the cranial end and grows in a cranial to caudal direction. The cranial region of the plate indicates the future brain.
By the end of the third week, the lateral edges of the plate become elevated and more together to form the neural folds. The resulting space in the middle is known as the neural groove. The folds will eventually fuse and from the neural tube. This is the pre-cursor for the CNS.
Fusion of the folds occurs firstly in the middle of the embryo and then heads in a cranial and caudal direction.
During folding, cells are the top detach and form a new cell population called the neural crest. These cells will contribute to the PNS.
121
What is the difference in positions of the neural tube and Primitive steak?
The neural tube begins at the cranial end and the primitive streak ends at the caudal end.
122
What happens during the fourth week of development?
The flat trilaminar disc folds into a cylinder. This occurs in the horizontal and median planes. In the horizontal place, there is the formation of the lateral body folds. In the median place, there is the cranial and caudal folds.
The endoderm moves towards the midline and fuses, forming the primitive gut tube. It forms the precursors for the midgut, hindgut and foregut. The midgut still remains in contact with the yolk sac. As folding increases, the yolk sac narrows and at its connection with the yolk sac, forms the vitelline duct
123
What does the neural tube and crest form?
The neural tube forms the CNS and the neural crest forms the PNS.
124
What proteins is DNA wrapped around?
Histones
125
What is the phenotype?
The physical appearance resulting from inherited information.
126
What is the genotype?
Gene constitution of an individual organism
127
What is the karyotype?
Number and appearance of chromosomes in the nucleus
128
Where does fertilization occur?
Ampulla
129
What is Capacitation and Acrosome reaction?
Capacitation: glycoprotein coat and seminal plasma protien removed from sperm hear
Acrosome reaction: acrosome like substances released to penetrate the zona pellucida
130
What happens to the endometrium before implantation?
It will thicken prior and expand due to the increase in oestrogen. It will become more vascularised and proliferates.
131
What is the shape of hypoblast cells?
Cuboidal
132
What is the shape of epiblast cells?
Columnar
133
What are the three mutations that cause Down syndrome?
Non-disjunction, Robertsonain translocation and Mosaic
134
What is trisomy 13?
Patau syndrome
135
What is the endocardial cushion?
A subset of cells involved in the developing heart which forms the valves and the septa
136
What cancer are people with Down syndrome more likely to get?
Megakaryoblastic form of acute myeloid leukaemia
137
What is the first trimester test during pregnancy?
This occur 11-14 weeks and involves a blood test an ultrasound. The blood measures for Pregnancy associated plasma-protein (PAPP-A) and Human Chorionic Gonadotropin (hCG). The ultrasound is measures the nuchal translucency.
138
What are the results of the first trimester test with a baby with Down syndrome?
- Low PAPP-A
- High hGC
- Increased nuchal lucency (this can also indicate Edwards syndrome)
139
What is trisomy 18?
Edwards syndrome
140
What does the Quadruple blood screening test look for?
- Alpha-fetoprotein (AFP): this is produced by featus, yolk sac and liver and it can diffuse through placenta. Low levels will indicate DS, Edwards etc
- Human Chorionic Gonadotropin: elevated levels can show DS and lowered levels can show Edwards
- Estroil: this is a type of oestrogen produced by foetus and placenta. It normally increases during pregnancy and hence low levels are associated with DS and Edwards
- Inhibin A: this is a protien secreted by ovaries and levels are increased with DS
141
When is amniocentesis, chronic villi sampling and cordocentesis performed?
Amniocentesis: after 15 weeks
Chorionic Villi sampling: after 10 weeks
Cordocentesis: after 19 weeks
142
What test is done in the first ten weeks of pregnancy?
Screening for sickle cells disease and thalassemia
143
What test is done during 8-12 weeks of pregnancy?
Blood test for HIV, Hep B and syphilis
144
What test is done during 18-21 weeks of pregnancy?
Physical abnormalities
145
What are the screening results for DS?
PAPP-A levels are low
| Free beta-hCG and NT measurement is raised
146
What are the screening results for Edwards and Patau?
PAPP-A and Free beta-hCG levels are low
| NT measurement is raised
147
What is sensitivity?
Screens ability to refer individual who do have target condition
148
What is specificity?
Screens ability to not refer individuals who don't have condition
149
What is the risk of giving a DS baby at aged 20 compared to 45?
20 years: 1/1500
| 45 years: 1/50
150
How does a mother's immune system not reject a baby?
Secretion of Neurokinin K and Small lymphocytic suppressor cells inhibit CD8+ by inhibiting IL-2. Placenta does not express MHC 1.
151
What is Bias?
This is a systematic design in a stud that results in mistaken estimates of and given factor.
152
How do you calculate Sensitivity?
(true positive)/(true positives + false negatives)
153
How do you calculate Specificity?
(true negatives)/ (true negatives + false positives)
154
What forms the notochord?
Mesenchyme from mesoderm. This runs the length of the embryo.
155
How is pre-eclampsia diagnosed?
Blood Pressure >140/90mmHg and proteinuria: >300mg in 24 hours
156
What is the blood pressure got to be above for the diagnosis of pre-eclampsia?
>140/90mmHg
157
What is the proteinuria got to be above for the diagnosis of pre-eclampsia?
>300mg in 24 hours
158
What effect would tetracycline have during pregnancy?
Teeth enamel
159
What effect would sodium valproate have during pregnancy?
Neural tube defect
160
What effect would Thalidomide have during pregnancy?
Limb development
161
What does sodium valproate treat?
Epilepsy
162
How many cervical somite pairs are there?
8
163
When do primary villi form?
Day 14
164
When do secondary villi form?
Day 16
165
During late pregnancy, what is the rate of water flow into placenta?
3.5 litres an hour
166
How do drugs cross the placenta?
Simple diffusion
167
What is the difference between the early placenta and late placental barrier?
The early barrier has both the syncytiotrophoblasts and cytotrophoblast layer.
The late barrier has no cytotrophoblast. There are more blood vessels and the mesenchyme core will become more dense.
168
What are Hafobauer cells?
Placenta macrophages
169
At full pregnancy, what is the rate of maternal blood flow?
500ml/min
170
What is a malformation?
Structural defect of body caused by an abnormal process intrinsic to its development.
171
What is a disruption?
Defect in body caused by a process that interferes with an originally normal process
172
What is a deformation?
Structural abnormality caused by mechanical forces
173
What word describes a structural defect in the body caused by an abnormal process intrinsic to its development?
Malformation
174
What is an example of a malformation?
Spina bifida
175
What work describe a structural defect caused by mechanical forces?
Deformation
176
What word describes a defect in the body caused by a process that interferes with an originally normal developmental process
Disruption
177
What is raised body temperature of the other associated with?
Anencephaly
178
What are the six domains of life?
- Physical
- Spiritual
- Social relationships
- Psychological
- Environment
- Dependence level
179
What is the fetal part of the placenta called?
Villus chorion
180
What is the maternal part of the placenta called?
Decidua Basalis
181
What holds the maternal and fetal portion of the placenta together?
Anchoring villi
182
What are the lobes on the maternal side of the placenta called?
Cotyledons
183
What are cotyledons?
Lobes on the maternal side of the placenta that roughly mark the villous tree
184
Why is there no blood flow into the lacunae of the placenta in the first 10 weeks of pregnancy?
The trophoblast cells will initially plug the spiral arteries. This means there is no blood in the lacunae and hence very little oxidative stress. As the plug dissolves, the oxidative stress will increase and the placenta will produce anti-oxidants for protection.
185
Explain the process of gas exchange within the placenta
Maternal blood flows through the uterine arteries and reaches the intervillus space. The fetal blood, which is low in oxygen and nutrients, flows in umbilical arteries to fetal capillaries and returns through umbilical veins.
186
How is glucose transported across the placenta?
Facilitated diffusion: hexose transporters
187
How are amino acids transported across the placenta?
Active transport
188
What does the Baker hypothesis state?
Babies that are too small are predisposed to adult disease
189
What is the blood pressure and proteinuria in pre-eclampsia?
Blood Pressure: >140/90
Proteinuria: >300mg in 24 hours
This is after 20 weeks of gestation
190
What is the fetal portion of the placenta called?
Villus Chorion
191
What is the maternal portion of the placenta called?
Decidua Basalis
192
When would a chorionic villus sampling take place?
10-14 weeks
193
What would amniocentesis take place?
14-16 weeks
194
What is the meaning of malformation?
This is where there is a structural defect in the embryo caused by an abnormal process intrinsic to normal process
195
What is the meaning of disruption?
A defect in the embryo caused by a process that interferes with the normal development
196
What is the meaning of deformation?
This s a structural defect caused by mechanical forces
197
What is the critical time for facial development?
Weeks 6-9
198
If a pregnant women get Rubella virus in the first three months, what would be the effect caused in the 6th week?
Cataracts
199
If a pregnant women get Rubella virus in the first three months, what would be the effect caused in the 9th week?
Deafness. This is due to the destruction of the Organ of Corti.
200
What is the purpose of the Bradford Hill criteria?
This provides epidemiological evidence of a casual relationship between a presumed cause and the observed effect
201
What is the nucleus pulposes derived from?
Notochord
202
Where is the intermediate mesoderm in comparison to the somites?
Ventrolateral
203
What does the parietal and visceral layers form?
The parietal layer together with overlying ectoderm forms the lateral body wall folds. The visceral layer forms the walls of the gut tube.
204
What is the only antibody that crosses the placenta?
IgG
205
What forms the exocoelemic membrane?
Cells from the hypoblast
206
What two layers surround the primitive yolk sac?
Hypoblast and exocoelemic membrane
207
What is the meaning of Phenotype?
The physical appearance resulting from inherited information
208
What is Karyotype?
The number and appearance of chromosomes
209
What is Genotype?
Genetic constitution of an organism
210
What are the three different ways there can be an extra chromosome 21?
- 95% non-disjunction
- 4% Robertsonain Translocation
- 1% Mosaic
211
What are the five acrocentric chromosomes?
13, 14, 15, 21, 22
212
What does it mean by an acrocentric chromosome?
The centromere is located near the end. This means there is both a short and long arm.
213
What are some clinical features of Down syndrome?
- Flat nasal bridge
- Slanted eyes
- Poor muscle tone
- Single crease on hands
- Large tongue and small mouth
- Short mouth
- Small ear
- Short fingers
214
What is meant by primary prevention?
This is the system of preventing a disease
215
What is meant by secondary prevention?
This is where someone has a disease nut no symptoms. This type of prevention aims to prevent the symptoms occurring.
216
What is meant by tertiary prevention?
This is where there is disease and symptoms. The prevention aims to decrease complications.
217
What is the phenotype of someone with Down syndrome?
- flat and wide face
- protruding tongue and wide face
- flat nasal bridge
- single crease on hand
- short neck
- increased leukaemia risk
- slanted eyes
- mental retardation
- small ears
- large space between first two toes
- small chin
- heart defects
