Misc Flashcards
1
Q
What happens to the mesonephric and paramesonephric ducts in male development? What part of the male DNA allows these changes to occur?
A
Mesonephric - becomes vas deferens
Paramesonephric - obliterated by production of mullerian inhibiting substance in males
SRY genes on the Y chromosome
2
Q
What are the mesonephric and paramesonephric ducts AKA?
A
Mesonephric - Wolffian duct
Paramesonephric - Mullerian duct
3
Q
What occurs in Turner’s syndrome? When and how is it diagnosed? What is the chromsomal classification?
A
- 45,XO.
- Results in degeneration of ovaries at 15th week of gestation.
- Diagnosis only occurs post puberty, when a lack of a menstrual cycle and secondary sexual characteristics are revealed.
4
Q
What is the function of hCG and hPL (human placental lactogen)?
A
HCG - Promotes progesterone release form corpus luteum
hPL - Decreases maternal insulin and glucose utlitisation. Increases lipolysis.
5
Q
What is the name of the visceral layer that covers the testis?
A
Tunica Vaginalis
6
Q
What occurs post puberty with regards to spermatogenesis? How long does spermatogenesis take? How long does it take for new groups of spermatogonia to arise? What occurs during copuluation? Where do spermatozoa mature?
A
- At intervals, A1 spermatogonia emerge from population of stem cells, marking beginning of spermatogenesis in that part of the tubule.
- The A1 spermatogonia divide to produce more type A (stem) cells or Type B cells
- Type B spermatogonium divides to produce 64 clones of primary spermatocytes all linked together by a cytoplasm bridge
- Chain of primary spermatocytes push out of lumen of tubule and begin meiosis, producing 256 sperms per A1 spermatogonium.
- After meiosis complete, spermatids remodelled to form sperm by spermiogenesis and the cytoplasmic bridges are broken down. They are then released into the tubule lumen and washed down the rete testis by fluid secreted from Sertoli cells.
- Spermatogenesis takes 70 days and new groups of spermatogonia arise every 16 days.
- Production of sperm is continuous as different sections of the tubule begin the process at different times, therefore some part is always released sperm – Spermatogenic wave of production.
- Spermatozoa mature during progress through epididymis.
- During copulation, contraction of vas deferens sweep sperm to be mixed with seminal and prostate secretions.
Stem cells –> A1 Spermatogonia –> Type B spermatogonia –> primary spermatocytes (linked) –> Spermatids –> sperms (unlinked)
7
Q
Distinguish between a spermatogenic cycle and a spermatogenic wave
A
Spermatogenic cycle – Development of A1 spermatogonia through to 256 sperms. Time taken for the same stage of the cycle to reappear in the same segment of tubule.
Spermatogenic wave – Different parts of tubule start the spermatogenic cycle at different times, so a constant ‘wave’ of production of sperm occurs. This can be thought of as the distance between 2 parts of the tubule on the same stage in the spermatogenic wave.
8
Q
What happens before birth in the ovarian cycle? What are the 3 stages that a follicle must go through to mature? Can a woman produce more oocytes, why?
A
- Primordial germ cells in the primordial gonad, AKA oogonia, proliferate by mitosis to form primary oocytes.
- Oogonia’s entry to meiosis 1 stimulated by mesonephric cells which surround the primary oocytes to form primordial follicles.
- Meiosis arrested at prophase due to oocyte maturation inhibitor (OMI) secreted by primordial follicles.
- A woman therefore has all the oocytes she will ever have at birth. The longer the oocytes remain in an arrested stage the increases chances there are of cell damage.
- A small number of follicles begin further development each day post puberty, formation of a mature gamete requires follicles to go through 3 stages.
3 stages are - primordial follicle, secondary follicle, pre-ovulatory follicle
9
Q
What happens in the primordial follicle stage to form the primary follicle?
A
- The primary oocyte grows dramatically
- Squamous granulosa cells become cuboidal Granulosa cells
- Zona pellucida forms around oocyte
10
Q
What happens to the primary follicle to get to the secondary follicle? What substance does the theca produce?
A
- Inner and outer theca forms
- Theca secretes oestrogens
- Fluid filled vesicles develop among granulosa cells
11
Q
What happens in the secondary follicle stage? What cells do FSH and LH bind to?
A
- Fluid filled vesicles combine to make one antrum
- Continued development depends on reproductive hormones.
- FSH – Binds only to Granulosa cells
- LH – Binds only to Thecal cells
12
Q
What happens in the pre-ovulatory stage? How many hours before ovulation does the phase start? After how many hours do unfertilised cells degenerate?
A
- Phase begins 37 hours before ovulation
- Oestrogen causes receptors for LH to appear on outer Granulosa cells
- LH surge stimulates these receptors, leading to rapid changes in the follicle
- Within 3 hours of the LH surge, the follicle restarts meiosis, and the first meiotic division is completed. This division is asymmetric; cytoplasm remains with one daughter cell and the other forms a condensed polar body.
- The secondary follicle then enters meiosis II and arrests again 3 hours prior to ovulation.
- LH stimulates collagenase activity leading to follicle rupture
- Ovum is carried out in the fluid and gathered up into the fallopian tube by fimbria
- Meiosis is not completed unless the ovum is fertilised
- Unfertilised cells degenerate 24 hours after ovulation
13
Q
What would happen to an XY individual with genitalia that are insensitive to testosterone or DHT?
A
- Testes remain in abdomen but removed post puberty due to high risk of malignancy
- Well developed breasts, no pubic hair or menstruation
- Genital ambiguity
14
Q
What would happen in an XX individual and excessive androgen secretion?
A
External appearance is male but genetically female with internal genitalia of both sexes
15
Q
What would happen to an XY individual with resistance to MIH?
A
Genetically and gonadally male but internal genitalia of both sexes due to test promoting external genitalia and wolffian duct.
Testes will fail to descend
16
Q
What are the glycoprotein hormones that the ant pit secretes? What cell type produces each hormone?
A
FSH – produced by gonadotrophs
LH - produced by gonadotrophs
TSH - produced by thyrotrophs
17
Q
What are the polypeptide hormones that the ant pit secretes? What cell type produces each hormone?
A
GH - produced by somatotrophs
ACTH - produced by Corticotrophs
Prolactin - produced by lactotrophs
18
Q
What are the hormones that the post pit produces?
A
ADH Oxytocin (important for reproduction)
19
Q
What is the action of GnRH in males? What is the action of FSH and LH? What is inhibin secretion rate related to? What else can affect the production of testosterone?
A
- Testosterone reduced GnRH secretion
- Spermatogenesis occurs continuously and male must be ready for action at any time. Therefore, hormone levels constant in medium and long term, achieved by –ve feedback
- FSH binds to Sertoli cells
- LH binds to Leydig cells:
- Promotes testosterone release and spermatogenesis
- Inhibin secretion related to rate of spermatogenesis.
- Testosterone is higher in mornings due to circadian rhythms and can be affected by environmental stimuli
20
Q
What does inhibin do in both sexes? What is inhibin secretion related to?
A
Inhibin from gonad reduces FSH secretion
Inhibin secretion related to developing gametes - More developed gametes release more inhibin
21
Q
What is the action of LH during the luteal phase? What about progesterone? How do progesterone only contraceptives function?
A
LH maintains corpus luteum
Progesterone in this stage acts on oestrogen primed cells:
Further thickening of endometrium
Thickening of myometrium
Thick, acid cervical mucus – barrier against sperm and bacteria between uterus and vagina. This is how progesterone only contraceptives work.
Changes in mammary tissue
22
Q
At the beginning of the menstrual cycle, what are the levels of progesterone and oestrogen? What happens here?
A
Low progesterone and oestrogen
FSH levels rise:
- Binds to granulosa cells
- Theca interna develops
- Secretes oestrogen stimulated by LH
- Secretes inhibin
23
Q
What happens in the mid follicular stage?
A
- Oestrogen levels rising
- Inhibin levels rising – inhibit FSH, no new follicles can develop
- Oestrogen exerts +ve feedback at hypothalamus and pituitary
- LH levels rise but not FSH
24
Q
What happens in the pre-ovulatory phase?
A
LH surge. Precise timing may be influenced by environmental factors
25
What happens after the luteal phase if there is a preganancy?
If pregnancy occurs, HCG released by placenta preserves corpus luteum. Corpus luteum secretes increasing amounts of steroids but placenta soon secretes even more and after 12 weeks corpus luteum no longer supports pregnancy.
26
Why does the menstrual cycle vary in length? How many days is it from ovulation to menses?
Variation in timing of ovulation. From ovulation to menses always takes 14 days
27
During what ages doees puberty occur for males and females?
Females: 8-13
Males: 9-14
28
What is the female process of puberty?
1. Breast bud (thelarche)
2. Pubic hair growth begins (adrenarche)
3. Growth spurt
4. Onset of menstrual cycle (menarche)
5. Pubic hair adult
6. Breasts adult
29
What is the male process of puberty?
1. Genital development begins
2. Pubic hair growth
3. Spermatogenesis begins
4. Growth spurt
5. Genitalia adult
6. Pubic hair adult
30
What are the effects on the body of menopause on oestrogen sensitive tissue? What about on bone? How can you reverse the changes done to bone?
Vascular changes – hot flushes, relieved by oestrogen treatment
On oestrogen sensitive tissues:
* Uterus – regression of endometrium, shrinkage of myometrium
* Thinning of cervix
* Vaginal rugae lost
* Involution of some breast tissue
* Changes in skin
* Changes in bladder
Bone:
* Bone mass reduces 2.5% per year
* Increased reabsorption relative to production
* Osteoporosis
* Limited by oestrogen therapy
31
Define amenorrhoea
absence of menstruation
32
Define menorrhagia
Heavy periods
33
Define dysmenorrhoea
Painful periods
34
Define oligomenorrhoea
Lots of small periods
35
Define cryptomenorrhoea
hidden periods
36
What is dyfunctional uterine bleeding (DUB)?
Excessively heavy, prolonged or frequent bleeding of uterine origin that is not due to pregnancy, pelvic or systemic disease
Anovulatory
37
Define primary amenorrhoea and secondary amenorrhoea. To what age group does secondary amenorrhoea usually occur?
Primary amenorrhea – Absence of menses by age 14 with absence of 2ndary sexual characteristics (SSC)
Secondary amenorrhoea: Where an established menstruation has ceased.
* 3 months in a women with a history of regular cyclic bleeding
* 9 months in a woman with a history of irregular periods
* Usually happens to women aged 40-55 (menopause)
38
Describe the pathophysiology of DUB
* Disturbance in the HPO axis thus changing in the length of menstrual cycle
* No progesterone withdrawal from an oestrogen-primed endometrium
* Endometrium builds up with erratic bleeding as it breaks down
39
How do you manage DUB?
* HCG, TSH
* Smear if appropriate
* Possible malignancy
* Oestrogen therapy
* Followed by cyclic progesterone for 10 to 12 days each cycle
40
What is menorrhagia?
Heavy bleeding that isnt DUB
Usually ovulatory
41
What is the pathophysiology of menorrhagia?
* Usually secondary to distortion of uterine cavity – heavy with or without prolongation
* Uterus unable to contract down on open venous sinuses in the zona basalis
42
How do you manage menorrhagia?
NSAIDS or combined oral contraceptibe pill
43
What are the disadvantages of HRT?
Increased risk of thromboembolism and breast cancer
44
What embryological structures fuse to form the uterus?
Mesonephric ducts
45
46
47
48
49
50
What is the internal lining of the uterus called? Which layer is subject to growth and shedding?
endometrium
Stratum functionalis
51
What are the 3 phases of the endometrium? What occurs to hormone secretion during each stage?
1. Proliferative phase of endometrium – oestrogen secreted during folliculogenesis
2. Secretory phase of endometrium – corpus luteum secretes progesterone which stimulates endometrial glands to secrete glycogen and encriching vascular supply to mucous membrane
3. Menstrual phase – conceptus failes to implant. Withdrawal of hormones. Changes in vascular supply of endometrium and degeneration of bulk of upper endometrium
52
What is the position of the uterus in relation to the vagina and cervix?
AnteVerted – In relation to Vagina
AntifleXed – In relation to the cerviX
53
What are the 3 parts of the broad ligament?
mesovarium, mesosalpinx, mesometrium
54
What is the lining of the endocervix and exocervix?
Endocervix:
Lined by columnar epithelium
Exocervix:
Stratified squamous non keratinised epithelium.
55
What innervates the uterus and vagina?
Inferior 1/5th of vagina receives somatic innervation from pudendal nerve S2-S4
Superior 4/5ths of vagina and uterus receives innervation from uterovaginal plexus
56
Where does the pain refer in vaginal/uteral injuries?
Above pelvic pain line – pain refers back up
Below pelvic pain line – pain refers locally
57
What is salpingitis? What can it lead to and how? How can it result in ectopic pregnancies?
* Inflammation of uterine tube caused by MOs
* Causes fusions or adhesions of mucosa and can block its lumen leading to infertility
* Blocked or dysfunctional tubes may result in ectopic pregnancies
58
What is endometriosis? What are the symptoms?
* Ectopic endometrial tissue is dispersed to various sites along the peritoneal cavity and beyond
* Associated with severe period pain and/or infertility
59
Where is an endoetrial carcinoma likely to occur? What is a symptom?
* Junction between columnar cells of endocervix and squamous cells of exocervix is wher emost neoplasma form
* Major symptom Is abnormal uterine bleeding
60
What is vaginismus?
Reflex of pubococcygeus muscle makes vaginal penetration painful or impossible
61
62
What are the 3 layers of the uterus?
endometrium, myometrium, perimetrium
63
64
65
66
What are the 4 muscles located in the root of the penis? What is their action?
* Bulbospongiosus x2 – Found in the bulb. Contacts to empty spongy urethra of any residual semen or urine. Anterior fibres aid in maintaining erection by increasing pressure in the bulb of the penis.
* Ischiocavernosus x2 – Surrounds left and right crura. Contracts to force blood from cavernous spaces in the crura into the corpus cavernosa, helping to maintain an erection.
67
What is the suspensory ligament a condensation of? What does it connect?
condensation of deep fascia. Connects erectile bodies to pubic symphysis
68
What is the fundiform ligament a condensation of?
Condensation of abdominal subcutaneous tissue
69
What is the innervation of the penis? Which spinal nerve roots? What nerve supplies sensory, sympathetic and PS innervation?
* Supplied by S2-S4
* Sensory and sympathetic innervation supplied by pudendal nerve
* PS innervation is from prostatic nerve plexus.
70
What is peyronie's disease? What are the symptoms?
* Abnormal curvature of shaft of penis caused by build up of scar tissue
* Pain on erection
71
What is priapism? What can happen?
* Erection for more than 4 hours
* Caused by blood being trapped in erectile bodies
* Can lead to scarring and ED.
72
What lymphatic nodes drain the testes? Where are they located?
lumbar and preaortic nodes located at L1
73
What is varicocoele? Why is the left more commonly affected?
dilation of veins. Left testicle more commonly affected due to drainage into smaller left renal vein at a perpendicular angle.
74
What arteries feed the scrotum?
anterior and posterior scrotal arteries arising from external and internal pudendal arteries respectively
75
What is the cutaneous innervation of the antero lateral scrotum?
geintal branch of genitofermoal nerve
76
What is innervation for anterior and posterior scrotum?
Anterior and posterior scrotal nerves
77
What is the innervation of the inferior scrotum
Perineal branches of posterior femoral cutaneous nerve
78
What drains the lymphatics of the scrotum?
Superficial inguinal nodes
79
What are the 3 fascial layers of the spermatic cord and where are they each derived from?
* External spermatic fascia – derived from aponeurosis of external oblique
* Cremaster muscle and fascia – internal oblique and its fascial oblique
* Internal spermatic fascia – transversalis fascia
* 3 fascial layers also covered by layer of superficial fascia which lies underneath scrotal skin
80
What is the cremasteric reflex? How is it stimulated and which nerves are involved?
* Stimulated by stroking superior and medial thigh
* Produces contraction of cremaster muscle, elevating testis on ipsilateral side.
Spinal reflex consists of 2 parts:
* Sensory limb – genitofemoral nerve
* Motor limb – genital branch of genitofemoral nerve
81
Name the contents of the spermatic cord. there are 9 things!!!
Spermatic cord contents "3 arteries, 3 nerves, 3 other things":
3 arteries: testicular, ductus deferens, cremasteric.
3 nerves: genital branch of the genitofemoral, cremasteric, autonomics.
3 other things: ductus deferens, pampiniform plexus, lymphatics.
82
What is the secretion of the prostate gland and what does it do?
* Secretes proteolytic enzymes into semen which act to break down clotting factors in the ejaculate.
* Allows semen to remain in a fluid state
83
What is the sympathetic, PS, and sensory innevation of the prostate?
Sympathetic, PS, and sensory form inferior hypogastric plexus.
84
How does benign prostatic hyperplasia present? Which area of the prostate enlarges?
* Compresses on both bladder and urethra
* Presents with urinary frequency, urgency and difficulty initiating micturition
* Enlargement in the transitional zone of prostate
85
How does prostatic carcinoma preesent? Which area of the prostate enlarges?
* Compresses on both bladder and urethra
* Presents with urinary frequency, urgency and difficulty initiating micturition
* Malignant cells commonly originate from peripheral zones, therefore symptoms present late in the disease.
86
Where is the bulbourethral gland found? What is its epithelium?
* Bulbourethral glands found enclosed within fibres of the external urethral sphincter.
* Lined by columnar epithelium
87
What is the lymphatic drainage of the bulbourethral gland?
Internal and external iliac lymph nodes
88
What do the seminal vesicles contribute to semen?
Produces 70% of volume of semen:
* Alkaline fluid
* Fructose – provides energy source for spermatozoa
* Prostaglandins – Suppress the female immune response to foreign semen
* Clotting factors – designed to keep semen in the female reproductive tract post ejaculation
89
What structures are derived from mesonephric ducts embryologically?
SEED
## Footnote
Seminal glands, Ejaculatory ducts, Epididymis, Ductus deferens are all derived from mesonephric ducts.
90
What is the lymphatic drainage of the seminal vesicles?
external and internal iliac lymph nodes
91
Why is a right sided varicocoele more worrying than a left sided one?
Right is more indicative of problems such as raised IVC pressure due to an obstruction
Right test vein attaches straight to IVC
Left sided is also more likely due to a lack of valves in the left test vein
92
93
What are the 2 holes found in the pelvic floor. What is their function?
* Urogenital hiatus – anteriorly positioned, allows passage of urethra (and vagina in females).
* Rectal hiatus – centrally positioned, allows passage of anal canal.
94
What is the innervation of the levator ani muscles?
Pudendal S2-4
95
What are the 3 muscles which make up the levator ani?
pubococcygeus, puborectalis, iliococcygeus
96
What is the perineal body and its function?
Connective tissue mass in centre of perineum
Anchors perineal muscles and rectum
97
What are the boundaries of the perineum?
Anterior – Pubic symphysis.
Posterior– The tip of the coccyx.
Laterally – Inferior pubic rami and inferior ischial rami, and the sacrotuberous ligament.
Roof – The pelvic floor.
Base – Skin and fascia.
98
What can the perineum be subdivided into?
Anterior urogenital triangle
Posterior anal triangle
99
What are the contents of the anal triangle?
Anal aperture
External anal sphincter
2 ischioanal fossae
100
What are the layers of the urogenital triangle?
1. Skin
2. Superficial perineal fascia
3. Deep perineal fascia
4. Superficial perineal pouch
5. Perineal membrane
6. Deep perineal pouch
101
What is contained in the deep perineal pouch in males and females?
Both - part of urethra and external urethral sphincter and deep transverse perineal muscles
Males - bulbourethral glands
Females - urethrovaginal sphincter
102
What is found within the superficial perineal pouch?
Both sexes - ischiocavernosus, bulbospongiosus, superficial transverse perineal muscle. Bartholin's glands.
103
104
What is the neurovascular supply to the perineum?
Pudendal - S2 to S4
Internal pudendal artery
105
How can damage to the perineal body during labour be avoided?
episiotomy - surgical cut in the perineum which prevents tearing of perineal body
106
How can damage occur to the pelvic floor during childbirth?
Mechanical - muscles stretched or pudendal nerve damaged.
Iatrogenic - damaged in episiotomy
107
Describe the physiological processes involved in emission. What spinal nerves are involved?
1. Movement of ejaculate into prostatic urethra – can get some leakage
2. Vas deferens peristalsis
3. Accessory gland secretions e.g. bulbourethral
4. contraction of glands and ducts
5. bladder internal sphincter contracts to prevent urine output
6. rhythmic striatal muscle contractions
Sympathetic L1,L2
108
Explain the mechanism through which the penis vasodilates
1. PS stimulation results in release of ACH to the endothelium of the artery
2. Ach bonds to M3 receptor and results in a rise in intracellular calcium, activation of NOS and formation of NO
3. NO diffuses into vascular smooth muscle and increases amount of cGMP in the smooth muscle cell. NO can also be released directly from nerves.
4. cGMP results in increased uptake of calcium in SER, therefore less calcium in cell --\> erection.
109
How does viagra work?
Works by inhibiting cGMP breakdown by PDE5
110
Describe what happens when a sperm meets an egg
1. Sperm pushes through granulosa cells and proteins on sperm head bind to ZP3 proteins of zona pellucida (ZP)
2. Binding triggers acrosome reaction:
1. Acrosomal enzymes released from sperm digest path through ZP
2. Sperm penetrates and fusion of plasma membrane soccurs
3. Sperm moves into cytoplasm to form a zygote
4. Polyspermy blocked by the cortical reaction
3. Egg completes Meiosis 2 and the 2 nuclei fuse
4. Cleavage occurs – a series of metabolic changes and rapid mitotic division, increasing number of cells without growth, forming morulla.
111
What is the capcitation of sperm? what happens in capacitation?
Maturing of sperm.
* Sperm cell membrane changes to allow fusion with oocyte cell surface – removal of glycoprotein coat
* Tail movement changes from a beat to a whip-like action.
* Sperm becomes responsive to signals from oocyte
112
What is the acrosome reaction of sperm and what happens during it?
Maturing of sperm when it comes into contact with oocyte zona pellucida
* Membranes fuse
* Acrosome swells and frees its content by exocytosis
* Proteolytic enzymes and further binding facilitate penetration of zona pellucida by sperm.
113
How does the combined OCP work?
* Oestrogen + progesterone
* –ve feedback to hypothalamus/pituitary inhibits follicular development
* No LH surge
114
What is the morning after pill? How does the morning after pill work?
Combined oestrogen + progesterone high dose up to 72 hours after intercourse
May disrupt ovulation, block implantation and impair luteal function
115
How do intrauterine contraceptive devices prevent pregnancy?
* Copper interferes with endometrial enzymes, and may also interfere with sperm transport into fallopian tubes
* Interferes with implantation.
116
What are the features of polycystic ovarian syndrome?
* Increased androgen secretion
* Raised LH/FSH ratio
* Insulin resistance
* Multiple small ovarian cysts
117
What is an ectopic pregnancy? What are the consequences?
* Implantation at site other than uterine body, commonly fallopian tube
* Can be peritoneal or ovarian
* Can rupture and cause severe haemorrhage
118
What is pre-eclampsia?
hypertension and large amount of protein in urine during pregnancy caused by incomplete invasion of placenta
119
How is the endometrium prepared for implantaiton?
Decidualisation – provides the balancing force for the invasive force of the trophoblast:
* Stimulated by progesterone
* W/o this complications such as haemorrhage can occur
Remodelling of spiral arteries:
* Creates low resistance vascular bed
* This maintains a high flow rate required to meet fetal demand.
120
What is the fetal portion and the maternal portion of the placenta made of?
Fetal - Formed by chorion frondsum
Maternal - Formed by decidua basalis
121
How does the thickness of the placenta change in the first and second trimester?
First trimester placenta:
* Placenta established
* Placental barrer to diffusion still thick
* Complete cytotrophoblast layer beneath syncytotrophoblast
Second trimester placenta:
* Loss of cytotrophoblast layer
* Barrier thin
* SA for exchange increased
122
Give 2 examples of pathogens able to cross the placenta
Cytomegalovirus
Rubella
123
What is haemolytic disease of the newborn? How is it treated?
* IgG antibodies produced by mother attacks RBCs of neonate.
* Due to incompatability of rhesus blood groups between mother and fetus.
* Mother prevbiously sensitised to rhesus antigen e.g. prevbious pregnancy
* Treated with prophylactic treatment
124
Why is there a decrease in BP during pregnancy?
* T1 and T2 – progesterone effects on systemic vascular resistance
* T3 – aortocaval compression by gravid uterus results in reduced return to heart. Can result in syncope when lying in supine position. Roll woman on left to relieve compression.
125
Why can urinary stasis occur during pregnancy? What are the possible consequences of this?
Progesterone relaxes smooth muscle of ureter which can result in stasis, hydroureter, UTIs, and pyelonephritis (PN can induce pre-term labour)
126
How does the metabolism of carbohydrates change for the mother? How do the hormones help do this?
* Progesterone stimulates appetite in first half of pregnancy and diverts glucose into fat synthesis
* Oestrogen stimulates increase in prolactin release, generates maternal resistance to insulin
* Maternal glucose usage thus declines and gluconeogenesis increases, maximising availability of glucose to fetus
* Later in pregnancy, mother’s energy needs are met by metabolising peripheral fatty acids
127
How does the insulin production change as pregnancy proceeds? Why do some women develop gestational diabetes as a result?
* Rate of secretion of insulin increases as pregnancy proceeds
* Achieved by beta cell hyperplasia and hypertrophy and increased rate of insulin synthesis in beta cell
* In some women, endocrine pancreas unable to respond to metabolic demand of pregnancy and cannot release enough insulin, results in loss of control of metabolism, blood glucose increases and diabetes results
128
What are the hallmark features of pre-eclampsia and how does this compare to a normal pregnancy?
Normal pregnancy:
* Vasodilated
* Plasma expanded
Pre-eclamptic pregnancy:
* Vasoconstricted
* Plasma contracted
* Raised blood pressure
* Proteinuria
* Pitting oedema
129
How much is cardiac output increased by in pregnant women?
40%
130
How much is HR increased by in pregnant women?
to 80/90
131
How much is o2 consumption increased by in pregnant women?
15%
132
How much is tidal volume increased by in pregnant women?
40%
133
What is reflex hypoglycaemia in a child?
If uncontrolled maternal diabetes occurs, foetus increases secretion of insulin.
Once isolated from other, neonate experiences reflex due to hgih circulating levels of insulin, can damage brain due to hypoglycaemia.
134
What are the 4 stages of development of the resp system? Name their time periods
1. Pseudoglandular: 8 to 16 weeks
2. Canalicular stage: 16 to 26 weeks
3. Terminal Sac stage: 26 week to term
4. Aleolar period: late fetal to 8 years
135
When does myelination of the spinal cord and the brain begin?
Spinal cord - 20th week
Brain - 36 week
136
What are the 5 factors measured in biophysical profiles? What does each test?
1. Fetal movement - nervous, MSK
2. Fetal tone - nervous, MSK
3. Fetal breathing - Resp, MSK, nervous
4. Amniotic fluid volume - Urinary, GI
5. Fetal Heart Rate - Resp
137
What are criteria that can be used to estimate fetal age? What measurements are specific to T1 and T2/3
* Foot length
* Weight after delivery
* Appearance after delivery
T1 - crown rump length
T2/3 - biparietal diameter of head
138
What is oligohydramnios? What can it cause?
* Too little amniotic fluid
* Can cause placental insufficency, fetal renal impairment, pre-eclampsia
139
What is polyhydramnios and what are its consequences?
* too much amniotic fluid
* Results in inability to coordinate swallowing movements and blind ended oesophagus
140
What happens after the baby takes its first breath?
* Pressure in lungs reduced leading to pressure in LA \> RA, closing foramen ovale
* Increased oxygen saturation in blood and removed prostaglandins results in constriction of ductus arteriosus and umbilical artery
* Stasis of blood in umbilical vein and ductus venosus leads to clotting of blood and closure due to subsequent fibrosis.
141
How much urine is produced at 25 weeks and at term?
25 weeks - 100 ml per day
at term - 500 ml per day
142
What is the average fetal heart rate at term?
140-160 bpm
143
Name the 2 proteins found in mature milk
lactoglobulin and lactalbumin
144
Describe how suckling promotes release of milk
Mechanical stimulation results in impulses travelling to hypothalamus and reducing secretion of dopamine and vaso-active intestinal peptide, promoting prolactin secretion.
145
Describe the hormonal control of milk let down. How does this hormone release milk and what other important function does it have?
Let down caused by increase in secretion of oxytocin.
Oxytocin contracts myoepithelial cells surrounding alveoli, ejecting milk. Also keeps uterus clamped down on open placenta blood vessels
146
How does cessation of lactation occur?
If suckling stops, prolactin levels decrease. Also milk in breast builds up and causes turgor induced damage to ducts.
147
What age do fibroadenomas occur most often\>
148
what age do phyllodes tumours most likely occur?
60s
149
What organism causes acute mastitis?
Staphylococcus aureus
150
What is acute mastitis? How is it treated?
Occurs during lactation due to nipple cracks and fissures. painful breast and often fevers. May be breast abscesses.
Treated by expressing milk and antibiotics.
151
What is duct ectasia?
dilation and inflammation of lactiferous duct. May have peri-areolar mass and/or nipple discharge
152
What can gynaecomastia indicate?
hormonal abormalities, cirrhosis of liver (oestrogen not broken down), fat people (adipocytes convert androgens to oestrogen), testicular tumour, drug use.
153
What is epithelial hyperplasia?
Epithelial cells get bigger and fill and distend ducts and lobules
154
If a breast cancer is palpable, what does that mean?
More than half of patients will have axillary lymph node metastases
155
What is the triple approach to investigating and diagnosing breast cancer?
Clinical - history, exam, and genetics
Radiographic imaging - mammogram, USS
Pathology - Fine needle aspiration cytology and core biopsy
156
What is CIN? What is the most common cause of CIN and cervical carcinomas and how does it do so?
Cervical intraepithelial neoplasia
HPVs - 16 and 18
HPV infects metaplastic squamous cells in transformation zone and produces proteins that interfere with tumour suppressor proteins.
157
What stain is used to examine cells from the transformation zone of the cervix?
papanicolaou stain
158
How is CIN 1, 2 and 3 treated?
1 - follow up or cryotherapy
2 and 3 - superficial excision
159
How does a cervical carcinoma present?
postcoital, intermenstrual, or post menopausal vaginal bleeding
160
How is a microinvasive and invasive carcinoma treated?
Microinvasive - cervical cone excision
Invasive - hysterectomy, lymph node dissection, radiation and chemo
161
What can be a precursor to endometrial carcinoma? What features does it contain? WHy does it occur?
endometrial hyperplasia
increased gland to stroma ratio
Occurs due to prolonged oestrogenic stimulation
162
What are the 2 main types of endometrial adenocarcinoma? How do they differ?
1. Endometrioid - mimics proliferative glands
2. Serous - poorly differentiated, aggressive, exfoilates and travels through fallopian tubes
163
What is a leiomyoma and how can it cause problems?
* Tumour of myometrium
* Benign
* Can be massive and cause heavy periods, bladder compression, infertility
164
How do ovarian tumours present?
* Abdo pain, abdo distension
* Urinary and GI symptoms
* Ascites
* Menstrual disturbances
165
What is pseudomyxoma peritonei?
Cancer that begins as polyp in the appendix and spreads through the wall.
Spreads to ovaries, peritoneum and can cause intestinal obstruction
166
What are the effects of ovarian sertoli-leydig cell tumours?
* Definiminsation and masculinisation
* Breast atrophy
* Amenorrhoea
* hair loss
* hirsuitism
* clitoral hypertrophy
167
Where does a vulval squamous cell carcinoma spread to?
Initially to inguinal, pelvic, iliac, and para-aortic lymph nodes
Then lungs and liver
168
What hormone indicates the possibility of an invasive mole during pregnancy?
HCG levels dont fall during pregnancy
