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18/03/2026

Diabetic Peripheral Neuropathy (DPN)

This illustration demonstrates the structural differences between healthy peripheral nerves and those affected by diabetic peripheral neuropathy. Under normal conditions, peripheral nerves are supplied by small blood vessels known as the vasa nervorum, which provide essential oxygen and nutrients required for proper nerve function. These nerves contain myelinated fibers, responsible for rapid signal transmission, and unmyelinated fibers, which conduct slower sensory impulses such as pain and temperature.

In diabetes, persistent hyperglycemia causes metabolic and microvascular damage. The vasa nervorum may become narrowed or occluded, leading to reduced blood supply and ischemia of the nerve tissue. As a result, both myelinated and unmyelinated nerve fibers undergo degeneration, impairing nerve conduction. Clinically, this manifests as numbness, tingling, burning sensations, reduced sensation, and weakness, most commonly affecting the distal extremities in a “glove and stocking” distribution.

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18/03/2026

11/03/2026

The arterial supply of the face is primarily derived from branches of the External Carotid Artery, particularly the Maxillary Artery, which plays a crucial role in supplying the deep structures of the face. In this illustration, key branches such as the Inferior Alveolar Artery, Infraorbital Artery, Buccal Artery, Masseteric Artery, and Mental Artery are highlighted. These vessels supply the teeth, mandible, maxilla, muscles of mastication, cheek, chin, and surrounding facial tissues.
The maxillary arterial network also gives rise to superior alveolar arteries that provide vascular supply to the maxillary teeth and gingiva, while the inferior alveolar artery travels through the mandibular canal to supply the mandibular teeth before terminating as the mental artery at the chin. Understanding this vascular anatomy is essential for clinical procedures such as dental surgery, maxillofacial operations, regional anesthesia, and management of facial trauma or hemorrhage.

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25/02/2026

Ej*******on – Full Educational Explanation
What Is Ej*******on?
Ej*******on is the release of semen from the p***s.Semen is a fluid that contains s***m and other substances.
Ej*******on usually happens during or**sm (sexual climax), but it can also occur during sleep (called a nocturnal emission or “wet dream”).

It is a normal and healthy function of the male reproductive system.

⸻

What Is the Function of Ej*******on?
Ej*******on has two main functions:
1. Reproduction
• Ej*******on delivers s***m into the female reproductive tract.
• If a s***m meets an egg, fertilization can occur.
• This is how pregnancy begins.
2. Sexual Pleasure
• Ej*******on is usually associated with or**sm.
• It is part of sexual response and intimacy.
• It is controlled by nerves, muscles, and hormones.How Does Ej*******on Happen? (Process)
Ej*******on occurs in two main phases:
1. Emission Phase
• S***m move from the te**es to the vas deferens.
• Fluids from the seminal vesicles and prostate mix with s***m.
• This forms semen.
2. Expulsion Phase
• Muscles contract rhythmically.
• Semen is pushed through the urethra.
• It exits the p***s.
The process is controlled by the nervous system.Is Ej*******on the Same in Everyone?
No. Ej*******on varies from person to person.Differences may include:
• Time to ej*******on
• Volume of semen
• Strength of release
• Sensation
• Frequency
Factors that affect ej*******on include:
• Age
• Physical health
• Mental health
• Hormones
• Stress level
• Sexual experience
• Frequency of sexual activity
• Medications
Variation is normal unless it causes distress or health problems.
What Is the Normal Time for Ej*******on?
There is no exact “perfect” time. Normal varies widely.Average time:
• During sexual in*******se: about 2 to 10 minutes after pe*******on.
• The release itself usually lasts a few seconds (5–30 seconds).
Some men ej*****te faster. Some take longer. Both can be normal.

13/02/2026

❇️ Pulse Evaluation: Assessment of arterial pulse points to determine heart rate, rhythm, and circulatory status.

🔹 Pulse Points & Their Locations

1. Temporal Artery
Location: Lateral side of the forehead, just above the zygomatic arch.

Clinical Use: Checking pulse in children; evaluating temporal arteritis.

2. Carotid Artery
Location: Anterolateral neck, between the trachea and sternocleidomastoid muscle.

Clinical Use: Checking pulse in emergencies; assessing cardiac output and cerebral perfusion.

3. Apical Pulse
Location: Over the apex of the heart, 5th intercostal space, mid-clavicular line.

Clinical Use: Auscultation preferred over palpation; used for cardiac assessment.

4. Brachial Artery
Location: Medial aspect of the antecubital fossa.

Clinical Use: Blood pressure measurement; evaluating circulation to the forearm and hand.

5. Radial Artery
Location: Lateral aspect of the wrist, proximal to the thumb.

Clinical Use: Common site for pulse checking; assessing peripheral circulation.

6. Femoral Artery
Location: Mid-inguinal point, midway between ASIS (anterior superior iliac spine) and p***c symphysis.

Clinical Use: Assessing lower limb circulation, cardiac output, and shock evaluation.

7. Popliteal Artery
Location: Deep within the popliteal fossa, behind the knee.

Clinical Use: Evaluating circulation to the lower leg, particularly in vascular disease.

8. Posterior Tibial Artery
Location: Behind the medial malleolus of the ankle.

Clinical Use: Assessing peripheral circulation, especially in diabetic patients.

9. Dorsalis Pedis Artery
Location: Dorsum of the foot, lateral to the extensor hallucis longus tendon.

Clinical Use: Checking foot circulation, especially in peripheral artery disease (PAD).

09/02/2026

The RAAS (Renin–Angiotensin–Aldosterone System) is a key
physiological mechanism that regulates blood pressure,
fluid balance, and electrolyte homeostasis.
Understanding it is essential for exams and clinical practice.

⚠️Disclaimer- For educational purposes only. Not medical advice. Consult a qualified healthcare professional.

09/02/2026

Radiotherapy and Immune Checkpoint Blockade: Converging on Antitumor Immunity👇

✅Radiotherapy as an inducer of immunogenic cell death
Radiotherapy (RT) promotes immunogenic cell death (ICD) in tumor cells. This process leads to the release and surface exposure of damage-associated molecular patterns (DAMPs), including calreticulin, HMGB1, ATP, and DNA fragments. These signals act as danger cues that alert and activate the immune system within the tumor microenvironment (TME).

✅Dendritic cell activation and T cell priming
DAMPs activate dendritic cells (DCs), enhancing antigen uptake and cross-presentation. Activated DCs prime CD8⁺ cytotoxic T lymphocytes, which then recognize tumor antigens presented on MHC molecules. This step is critical for initiating effective adaptive antitumor immunity.

✅cGAS–STING pathway activation by RT
RT-induced DNA damage results in the accumulation of cytosolic double-stranded DNA. This DNA is sensed by cGAS, which generates cGAMP to activate STING. Activated STING translocates to the Golgi and recruits TBK1 and IKK, triggering phosphorylation of IRF3 and NF-κB. These transcription factors drive the production of type I interferons and pro-inflammatory cytokines.

✅Remodeling the tumor microenvironment
Type I interferons and inflammatory cytokines reshape the TME toward a pro-immunogenic state. Regulatory T cells are reduced, tumor-associated macrophages are reprogrammed toward an M1-like phenotype, and the suppressive activity of myeloid-derived suppressor cells (MDSCs) is diminished. Cancer-associated fibroblasts and CD4⁺ T cells further amplify immune cell recruitment and effector responses.

✅Adaptive immune resistance via PD-L1 upregulation
Despite immune activation, cGAS–STING–TBK1–IRF3 signaling can induce PD-L1 expression on tumor cells. PD-L1 engagement with PD-1 on T cells leads to T cell exhaustion and adaptive immune resistance, limiting the durability of RT-induced antitumor immunity.

✅Synergy with PD-1/PD-L1 inhibitors

28/01/2026

🟣 Normal Newborn Skin Findings (First Days of Life)

These are physiologic neonatal skin changes seen in healthy newborns and require no treatment.

🟣 Vernix Caseosa

Definition:
→ Thick, white, cheesy material covering newborn skin at birth.

Composition:
→ Sebaceous secretions + desquamated epithelial cells.

Functions:
→ Acts as skin barrier
→ Prevents transepidermal water loss
→ Has antimicrobial properties
→ Provides lubrication during delivery

Clinical points:
→ Common in term babies
→ More abundant in preterm infants
→ Disappears spontaneously in few days

🟣 Lanugo

Definition:
→ Fine, soft, non-pigmented fetal hair.

Distribution:
→ Shoulders, back, forehead, ears.

Clinical points:
→ More prominent in premature infants
→ Normally sheds within first 2–4 weeks of life
→ No treatment required

🟣 Congenital Dermal Melanocytosis (Mongolian Spots)

Definition:
→ Blue-gray macular pigmentation due to dermal melanocyte entrapment.

Common sites:
→ Lumbosacral region
→ Buttocks

Characteristics:
→ Flat
→ Non-tender
→ Present at birth
→ Not raised

Epidemiology:
→ Common in Asian, African, Hispanic populations.

Course:
→ Gradually fades during early childhood.

Exam pearl:
→ Must be differentiated from bruising / child abuse.

🟣 Acrocyanosis

Definition:
→ Bluish discoloration of hands and feet with normal pink lips and tongue.

Cause:
→ Peripheral vasoconstriction due to immature neonatal circulation.

Timing:
→ First 24–48 hours after birth
→ May recur with cold exposure.

Important distinction:
→ Central cyanosis = lips/tongue blue → pathological
→ Acrocyanosis = peripheral only → physiologic

🟣 Physiologic Desquamation

Definition:
→ Peeling or scaling of newborn skin.

Sites:
→ Palms and soles commonly.

Cause:
→ Adaptation from amniotic fluid environment to dry air.

Timing:
→ Appears in first few days of life.

Course:
→ Resolves spontaneously within weeks.