Spermatogenesis is the process by which male germ cells develop into mature sperm cells. It begins at puberty and continues throughout a man's life. The process occurs in the testes and epididymis. In the testes, spermatogonia undergo mitosis and meiosis to form haploid spermatids. Spermatids then undergo spermiogenesis to form mature sperm, acquiring motility and other structures. Hormones like FSH, LH and testosterone regulate spermatogenesis, which produces several hundred million sperm daily.
In testis, the immature male germ cell (spermatogonia ) produce sperms by spermatogenesis
The spermatogonia ( sing. Spermatogonium ) present on the inside of seminiferous tubules multiply by mitotic division and increase in numbers
Each spermatogonium is diploid and contains 46 chromosomes
Some of the spermatogonia called primary spermatocytes periodically undergo meiosis.A primary spermatocyte completes the first meiotic division (reduction division) leading to formation of two equal, haploid cells called secondary spermatocyte, which have only 23 chromosomes
The secondary spermatocyte undergo the second meiotic division to produce four equal, haploid spermatids
presentation on oogenesis of fertilisation process full details about it u will never find it anywhere else have full details about the ovum formation polar bodies and everything . so explore here
In testis, the immature male germ cell (spermatogonia ) produce sperms by spermatogenesis
The spermatogonia ( sing. Spermatogonium ) present on the inside of seminiferous tubules multiply by mitotic division and increase in numbers
Each spermatogonium is diploid and contains 46 chromosomes
Some of the spermatogonia called primary spermatocytes periodically undergo meiosis.A primary spermatocyte completes the first meiotic division (reduction division) leading to formation of two equal, haploid cells called secondary spermatocyte, which have only 23 chromosomes
The secondary spermatocyte undergo the second meiotic division to produce four equal, haploid spermatids
presentation on oogenesis of fertilisation process full details about it u will never find it anywhere else have full details about the ovum formation polar bodies and everything . so explore here
The biological process via which the testes, the male reproductive organs, produce sperm cells is known as spermatogenesis. It begins with the development of immature germ cells from stem cells in the seminiferous tubule walls, which grow into mature sperm cells featuring a condensed nucleus, a head, and a tail.
The biological process via which the testes, the male reproductive organs, produce sperm cells is known as spermatogenesis. It begins with the development of immature germ cells from stem cells in the seminiferous tubule walls, which grow into mature sperm cells featuring a condensed nucleus, a head, and a tail.
This gives in detail about male reproductive system including Spermatogenesis.
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Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
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Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
2. Spermatogenesis is the process by which
male germ cell (spermatogonia) develop into
mature spermatozoa.
Spermatozoa are the mature male gametes in
many sexually reproducing organisms.
Thus, spermatogenesis is the male version of
gametogenesis.
In humans it takes on an average 74 days to
form a mature sperm
3. It starts at puberty and usually continues
uninterrupted until death, although a
slight decrease can be discerned in the
quantity of produced sperm with increase
in age.
The entire process can be broken up into
several distinct stages, each
corresponding to a particular type of cell:
4.
5. The initial stages occur within the testes and progress
to the epididymis where the developing gametes
mature and are stored until ejaculation.
The seminiferous tubules of the testes are the starting
point for the process, where stem cells adjacent to the
inner tubule wall divide in a centripetal direction.
The cells begin to divide at the walls proceeding
towards the lumen to produce immature sperm.
Maturation occurs in the epididymis and involves the
acquisition of a tail and hence motility.
6. Stages of Spermatogenesis
A diploid spermatogonium which resides in
the basal compartment of seminiferous
tubules, divides mitotically to produce two
diploid intermediate cell called a primary
spermatocyte.
Each primary spermatocyte then moves into
the adluminal compartment of the
seminiferous tubules and duplicates its DNA
and subsequently undergoes meiosis to
produce two haploid secondary
spermatocytes.
7. Secondary spermatocytes undergo a second
meiotic division to form spermatids with
haploid no of chromosomes.
Spermatids mature to form the Sperm/
spermatozoa and this process is termed
spermiogenesis.
During spermiogenesis, the spermatids begin
to grow a tail, and develop a thickened mid-
piece, where the mitochondria gather.
8. Spermatid DNA also undergoes packaging,
becoming highly condensed.
The DNA is packaged firstly with specific
nuclear basic proteins, which are subsequently
replaced with protamines during spermatid
elongation.
Maturation then takes place under the
influence of testosterone, which removes the
remaining unnecessary cytoplasm and
organelles
9. The excess cytoplasm, known as residual
bodies, is phagocytosed by surrounding Sertoli
cells in the testes.
The resulting spermatozoa are now mature but
lack motility, rendering them sterile.
The mature spermatozoa are released from
the protective Sertoli cells into the lumen of the
seminiferous tubule in a process called
spermiation.
11. A mature spermatozoa, or spermatozoon, has
3 distinct parts: a head, a mid-piece, and a tail.
The head contains 23 chromosomes within a
nucleus.
The tip of the nucleus is covered by a cap
called the acrosome, which contain enzymes
needed to breach the egg for fertilization.
The mid-piece contains energy-producing
mitochondria.
The tail is made up of microtubules that form
cilia and flagella.
12. It should also be noted that not all
spermatogonia divide to produce
spermatocytes, otherwise the supply
would run out.
Instead, certain types of spermatogonia
divide to produce copies of themselves,
thereby ensuring a constant supply of
gametogonia to fuel spermatogenesis.
13. A normal human male usually produces
several hundred million sperm per day.
The estimated number of spermatids
formed from a single spermatogonium is
estimated to be 512.
Sperm are continually produced
throughout a male's reproductive life,
though production decreases with age.
14. The non-motile spermatozoa are transported
to the epididymis in testicular fluid secreted by
the Sertoli cells with the aid of peristaltic
contraction.
Whilst in the epididymis they acquire motility
and become capable of fertilisation.
However, transport of the mature spermatozoa
through the remainder of the male
reproductive system is achieved via muscle
contraction rather than the spermatozoon's
recently acquired motility.
15. During ejaculation, sperm leaves the
penis in a fluid called seminal fluid
(semen).
This fluid is produced by 3 types of
glands, the seminal vesicles, the
prostate gland, and Bulbourethral gland
(Cowper's glands).
Each component of a seminal fluid has a
particular function.
16. Sperm are more viable in a basic solution, so
seminal fluid has a slightly basic pH balance.
Seminal fluid also acts as an energy source for
the sperm, and contains chemicals that cause
the uterus to contract.
An average volume per ejaculate is 2.5-3.5 ml
Normal sperm count is 100 million
sperms/ml
17. Role of Sertoli cells
Sertoli cells serve a number of functions
during spermatogenesis, they support
the developing gametes in the following
ways:
Maintain the environment necessary for
development and maturation via the
blood-testis barrier
Secrete substances initiating meiosis
Secrete supporting testicular fluid
18. Secrete androgen-binding protein, which
concentrates testosterone in close
proximity to the developing gametes
Secrete hormones effecting pituitary
gland control of spermatogenesis,
particularly the polypeptide hormone,
inhibin
Inhibin decreases FSH secretion.
Phagocytise residual cytoplasm left over
from spermiogenesis
19. Factors influencing
spermatogenesis
The process of spermatogenesis is highly
sensitive to fluctuations in the environment,
particularly hormones and temperature.
Testosterone is required in large local
concentrations to maintain the process, which
is achieved via the binding of testosterone by
androgen binding protein present in the
seminiferous tubules.
Testosterone is produced by Leydig cells,
which reside adjacent to the seminiferous
tubules.
20. Seminiferous epithelium is sensitive to
elevated temperature in humans and
spermatogenesis will be adversely affected by
temperatures as high as normal body
temperature.
Consequently, the testes are located outside
the body in a sack of skin called the scrotum.
The testes are kept cool at a temp. of about
32°C by;
Air circulating around the scrotum
Heat exchange in a counter current fashion
between the spermatic arteries and veins
21. Other factors influencing
spermatogenesis
Dietary deficiencies (such as vitamins B, E
and A)
Anabolic steroids
Metals (cadmium and lead)
x-ray exposure
Drugs like digoxin
Alcohol and
Infectious diseases will also adversely affect
the rate of spermatogenesis.
22. Composition of human semen
Color: white, opalescent
Sp gravity: 1.028
pH: 7.35-7.5
Average sperm count: 100 million/ml
Components:
Fructose
Prostaglandins
23. Ascorbic acid
Phosphorylcholine
Flavins
Cholesterol
Phospholipids
Fibrinolysin
Phosphate and bicarbonate buffers etc.
24. Hormonal control
Hormonal control of spermatogenesis varies
among species.
In humans the mechanism are not completely
understood, however it is known that initiation
of spermatogenesis occurs at puberty due to
the interaction of the hypothalamus, pituitary
gland and Leydig cells.
If the pituitary gland is removed,
spermatogenesis can still be initiated by follicle
stimulating hormone and testosterone.
25. During puberty the hypothalamus
releases gonadotropin-releasing
hormone (GnRH).
The anterior pituitary produces the
gonadotropins; follicle-stimulating
hormone (FSH) and luteinizing hormone
(LH).
26. Follicle stimulating hormone stimulates
both the production of androgen binding
protein by Sertoli cells, and the formation
of the blood-testis barrier.
FSH stimulates secretion of Inhibin
which has a negative feed back on FSH
secretion.
FSH may initiate the sequestering of
testosterone in the testes, but once
developed only testosterone is required
to maintain spermatogenesis.
27. Luteinizing Hormone
In both sexes, LH stimulates secretion of
sex steroids from the gonads.
In the testes, LH binds to receptors on
Leydig cells, stimulating synthesis and
secretion of testosterone.
Testosterone in turn inhibits LH secretion
29. Endocrine function of testes
(Testosterone)
Like other steroid hormones,
testosterone is derived from cholesterol.
The largest amounts of testosterone are
produced by the testes in men.
It is also synthesized in far smaller
quantities in women by the thecal cells of
the ovaries, by the placenta, as well as
by the zona reticularis of the adrenal
cortex in both sexes.
30. Like most hormones, testosterone is
supplied to target tissues in the blood
where much of it is transported bound to
a specific plasma protein (sex steroid
binding globulin).
31. Functions of testosterone
In general, androgens promote protein
synthesis and growth of those tissues
with androgen receptors.
In addition to their action during
development, it exerts an inhibitory
feedback effect on pituitary LH secretion.
It maintains spermatogenesis
32. Testosterone effects can be classified as
virilizing and anabolic, although the
distinction is somewhat artificial, as
many of the effects can be considered
both.
33. Anabolic effects include,
Growth of muscle mass and strength,
Increased bone density,
Stimulation of linear growth and
Bone maturation.
34. Virilizing effects include;
Maturation of the sex organs, particularly
the penis and the formation of the
scrotum in unborn children.
And after birth (usually at puberty) a
deepening of the voice, growth of the
beard and axillary hair.
Many of these fall into the category of
male secondary sex characteristics.
35. Secondary sex characteristics in
Male
Growth of body hair, including underarm,
abdominal, chest, and pubic hair
Greater mass of thigh muscles
Growth of facial hair
Enlargement of larynx and deepening of voice
Increased stature; adult males taller than adult
females, on average
Heavier skull and bone structure
36. Increased muscle mass and strength
Broadening of shoulders and chest;
shoulders wider than hips
Increased secretions of oil and sweat
glands, often causing acne and body odor
Coarsening or rigidity of skin texture, due to
less subcutaneous fat
A prominent Adam's apple
37. Fat deposits mainly around the abdomen
and waist
Higher waist to hip ratio than prepubescent
or adult females or prepubescent males, on
average
On average, larger hands and feet than
prepubescent or adult females or
prepubescent males
38. Mechanism of action of
Testosterone
Free testosterone (T) is transported into the
cytoplasm of target tissue cells, where it can
bind to the androgen receptor, or can be
reduced to 5α-dihydrotestosterone (DHT) by
the cytoplasmic enzyme 5-alpha reductase.
DHT is more potent than T.
DHT binds to the same androgen receptor
even more strongly than T, so that its
androgenic potency is about 2.5 times that of
Testosterone.
39. The T-receptor or DHT-receptor complex
undergoes a structural change that
allows it to move into the cell nucleus
and bind directly to specific nucleotide
sequences of the chromosomal DNA.
This influence transcriptional activity of
certain genes, producing the androgen
effects.
40. T-receptor complexes are responsible for the
maturation of wolffian duct structures and
consequently for the formation of male internal
organ during development.
DHT-receptor complexes are needed to form
the external genitalia in males
Note: if there is a 5-alpha reductase
deficiency, the male body will continue growing
into a female with testicles, condition called
pseudohermaphroditism.
41. Male pseudohermaphroditism
Individuals with this syndrome are born
with male internal genitalia with testes,
but have female external genitalia.
They are usually raised up like girls.
However, when they reach puberty, there
is LH secretion and the levels of
circulating testosterone increases.
Consequently they develop male body
contours.
42. Abnormalities of testicular function
CRYPTORCHIDISM: (undescended testes)
In this condition, after the formation of testes in
the abdomen, their descent is incomplete.
Chances of malignancy is high in
undescended testes than the scrotal testes.
This is because, after puberty the high
temperatures cause irreversible damage to the
spermatogenic epithelium.
Treatment is administration of gonadotropic
hormone in early childhood or surgical
correction
43. Male hypogonadism
The clinical picture depends upon
weather the testicular deficiency
develops before or after puberty.
In adults, if it is due to testicular disease,
circulating gonadotropin levels are
elevated- hypergonadotropic
hypogonadism
44. If the defect lies in the hypothalamus or
pituitary, circulating gonadotropin levels
are low- hypogonadotropic
hypogonadoism.
When the endocrine function of testes is
lost in adulthood, the secondary sex
characteristics regress gradually but the
voice remains deep as the laryngeal
growth is permanent.
45. When the Leydig cell deficiency starts from
childhood, the clinical picture is like that of
Eunuchodism.
Characteristic features are;
Individuals above 20yrs are tall (not as in
Gigantism) as their epiphysis remains open
and growth continues post puberty.
Narrow shoulders
Small muscles
46. Small genitalia
Voice high pitched
Pubic and axillary hair present due to
androgens from adrenal cortex but of the
female pattern