A HAIR RESEARCH

ELECTROLYSIS / SKIN RESEARCH

1. Explain the Integumentary System and include particular focus on hair, how it works/grows and what it is made of.
   The integumentary system, the largest organ in the human body, serves as a physical barrier that separates the external environment from the body's internal environment. The integumentary system comprises the hair, nails, dermis, hypodermis, and associated glands. The integumentary system serves multiple functions, including thermoregulation, maintenance of cellular fluid, vitamin D synthesis, detection of stimuli, and acting as a barrier. The system as a whole performs these activities. For instance, regulating body temperature is the responsibility of thermoreceptors, which subsequently impact peripheral blood flow, sweat, and hair growth (Kim & Dao, 2021).
    Hair is derived from the epidermal layer of the skin, with its roots extending deeply into the dermis. The two primary components of hair are the hair follicle, situated beneath the epidermis, and the hair shaft, visible externally. The hair bulb, located within the intricate structure of the hair follicle, undergoes active division to promote the elongation of the hair shaft in a vertical orientation. The only regions that remain uncovered include the palms and soles of the feet, the lips, and the external genitalia. Hair is crucial in safeguarding the skin against mechanical damage, augmenting sensory function, and regulating body temperature. The erector pili muscles connect to the hair follicles and provide support to the hair shaft. Additionally, they create a thermal barrier by retaining air close to the skin’s surface.
2. Explain the origin of hair and how hair grows in the body.
   Angiogenesis of the hair initiates at approximately ten weeks of gestation. Placodes are initial local thickenings that manifest on the scalp and facial regions. The placodes progress further into the dermis and differentiate into the hair germ and a dermal condensate cap. The formation of dermal papillae occurs as the hair germ develops, whereby the hair bulb epithelium encloses the dermal condensate. The root develops various layers, including a protective outer sheath, an inner sheath, a cuticle, a cortex, and a medulla. The sebaceous and apocrine glands originate from this particular structure (Murphrey et al., 2018). The visible hair follicle is the result of this development. In recent years, it has been identified that Vascular Endothelial Growth Factor (VEGF) plays a crucial role in hair angiogenesis (Yano et al., 2001).
3. Explain everything about the different types of hair.
• Terminal Hair
  Terminal hair, commonly called body hair, is typically characterized by its dense and dark appearance. The condition can affect multiple body regions, such as the scalp, face, armpits, and genital area. Terminal hair functions as a protective barrier for the body in various aspects. Maintaining a stable core temperature can be achieved naturally. It protects against the sun’s harmful rays to ensure the safety of your skin.
  Both children and adults possess terminal and non-terminal hair. The development and speed of terminal hair growth are influenced by several hormonal variables regulated by the endocrine system. Terminal hair growth is a secondary sexual characteristic that manifests during adolescence, similar to the development of breasts and penis. These changes in bodily functions are induced by androgens, a group of sexual hormones that are synthesized during the phase of puberty. The hormones exhibit differential sensitivity across different body regions ( Miranda et al., 2018).
• Vellus Hair
  Vellus hair is light, short, and fine in texture and is distributed throughout the entire human body. The length and thickness of the item in question vary according to the individual. The primary purpose of vellus hair is to provide a protective barrier to the skin and retain body heat. During puberty, hormonal changes trigger the transformation of specific vellus hair follicles into terminal hair follicles, resulting in heightened hair density in those areas.
  The density, color, and length of vellus hair exhibit inter-individual variation. The vellus hair of certain individuals may only be discernible when viewed nearby and under intense illumination. There is a noticeable variation in the thickness and darkness of vellus hair among individuals. Vellus hair exhibits thickness variations across different body regions (Vogt et al., 2007).
  The structure of vellus hair is similar to that of terminal hair. The hair follicle serves as the origin of hair growth for both the genitalia. The sebaceous gland within each hair follicle secretes sebum, an oily substance that lubricates the skin and hair. In contrast to terminal hair, vellus hair frequently lacks a medulla. The medulla is a structural element present in the cortex of hair that facilitates robust and expeditious growth.
• Lanugo Hair
  Hair with these characteristics—fine, supple, and lacking in pigmentation—is known as lanugo. Fetuses, babies, and people with particular medical disorders often have this hair. The appearance of lanugo in an older adult may indicatean underlying disease, even though it is a common finding in fetuses. Verhave et al. (2022) point out that lanugo formation is a cell- and molecular-intensive process essential for healthy embryonic growth.
  The fetal lanugo is essential for attaching the vernix caseosa to the epidermis. The term “vernix caseosa”describes the white, gelatinous fluid that covers infants and helps them retain moisture, regulate their body temperature, and develop an innate immune response. Amniotic fluid protects the embryo against urea and electrolytes, two potentially damaging chemicals (Faist, 2020).
   
4. Explain Pili Multigemini hairs in detail:
   These are hairs that grow multiple hairs from a single hair follicle. Researchers are not sure why these hairs grow this way, but are convinced that it tends to run in families. These overachieving follicles can happen anywhere on the body that hair grows, and does not seem to cause concern with research.
    
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5. Explain in detail the hair terms:
   Hairs in different locations are given specific names, e.g., cilia, capilli, tragi, vibrissae, pubes, and hirci.
    
• Cilia: Cilia are slender, microscopic, hair-like organelles that protrude from the surface of almost all mammalian cells. They are of ancient origin.
• Supercilia:“Supercilium” denotes the curved line of hair located precisely above each eye. The morphology and pigmentation of the eyebrow are primarily attributed to the superciliary region. The primary function of eyebrows is to protect the eyes by preventing debris from entering and salty sweat from running into them. Due to its anatomical position and distinctive shape, the eyebrow functions as an inherent barrier for the eyes, shielding them from direct sunlight and impeding the flow of sweat or tears from descending onto the forehead and entering the eye. The large eyebrow hairs possess numerous sensory innervations, rendering them highly responsive to tactile stimuli. An individual's emotional state can also be communicated through their eyebrows, specifically by lowering the inner portion of the eyebrow, which may indicate anger or anxiety. The facial expression of raising one eyebrow in inquiry is quite indicative. Facial expressions are a form of nonverbal communication utilized to convey emotions (Kar et al., 2013).
• Vibrissa: Whiskers, scientifically known as vibrissae, are prominent tactile hairs that develop in specialized hair follicles. The trigeminal nerve, also known as the fifth cranial nerve, offers distinct sensory innervation to every whisker on the face. The facial vibrissae are frequently arranged in distinct grid patterns indicative of a particular species. Each vibrissa has a corresponding barrel in the homologous grid. Each afferent fiber is linked with a specific receptor subtype in the hair follicle. These receptor subtypes work in conjunction to represent the movement of the whisker in both spatial and temporal dimensions. The modulation of vibrissal sensory signals is influenced by the coordination of motor activity (Woolsey, 2009).
• Capilla:  The hairs of the scalp.
• Hirci: The hairs which grow in the axilla.
• Pubes:  The hair on genitals
• Tragi:  The hairs growing at the entrance to the external acoustic meatus.
   
6. What are Eccrine, Apocrine, and Sebaceous Glands?
• The Eccrine sweat glands are the predominant type of sweat gland distributed extensively throughout the skin. Perspiration is generated by these glands and transported through convoluted ducts to the skin's surface.
• Apocrine glands are present in various parts of the human body, such as the epidermis, breast, eyelid, and ear. The apocrine glands in the breast are responsible for the secretion of lipid droplets into milk. In contrast, the apocrine glands found in the ear contribute to the production of cerumen, commonly known as earwax. The apocrine glands located in the skin and eyelids are responsible for producing sweat.
• Sebaceous glands, which are holocrine in nature, are present throughout the body's surface except for the feet' palms, soles, and dorsums. Sebum is a multifaceted oil comprising triglycerides, fatty acid breakdown products, wax esters, squalene, cholesterol esters, and cholesterol. These components are typically generated and excreted by the sebaceous glands. Sebum’s lubricating properties enhance the skin’s resistance to moisture and friction
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7. Explain all parts that attach to and are within a hair follicle.
   The formation of hair follicles and their associated appendages occurs through the development of specialized cell buds within the fetal epidermis at approximately 9 weeks of gestation. Dermal mesenchymal cells secrete chemicals like epimorphin, which tell dermal epithelial cells to multiply and move in a downward (craniocaudal) direction into the dermis. When this process is complete, the fetus will have a hair follicle with an ectodermal matrix and a mesodermal dermal papilla. Each follicle undergoes the development of an associated arrector pili muscle and sebaceous gland. To produce the lipid-rich sebum that mixes with desquamated stratum corneum cells to create the vernix caseosa, the fetal sebaceous glands must be activated in the womb by maternal androgens (Martel et al., 2017).
   The growth of lanugo hair during the fetal stage occurs after the hair follicle's formation. The hair follicles in question generate fine and abbreviated strands. With the time a baby is between 36 and 40 weeks along, most of its baby hairs have fallen out to be replaced with soft, downy vellus hairs. On the contrary, the terminal hairs on the scalp, eyebrows, and eyelashes exhibit greater thickness and coarseness. At puberty, the vellus hairs in this region are transformed into terminal hairs by androgen hormones, resulting in the growth of a beard. It is important to note that there is no further development of hair follicles postpartum. Even after birth, it is possible to increase or decrease the size of follicles (Grubbs et al., 2023) so that new hair may develop from the current ones.
    
8. Does the hair on your head grow differently than the rest of the hair on the body, and how?
   The hair on head grows in a different direction than the hair on your body, which explains why your head hair may become so long while your body hair stays relatively short. Head hair is so much longer than other hair because its follicles stay in the active growth (or anagen) phase for a much longer period (years, rather than months).
9. Explain how the Arrector Pili Muscle functions and works to make hair grow.
   The arrector pili muscle is a smooth muscle that exhibits dual attachment sites, namely the dermis and the hair follicle. The contraction of the arrector pili muscle results in the elevation of the hair follicle, leading to the formation of goosebumps.
   Hair follicle stem cells (HFSCs) are situated within the bulge of the hair follicle, which is connected by the erector pili muscles. Sympathetic pilomotor neurons stimulate the erector pili muscles to secrete norepinephrine (NE) in response to cold. This results in the contraction of the muscles and the erection of hair (Pascalau & Kuruvilla, 2020).
10. Explain how the Sebaceous Gland functions and works to make hair grow.
    During embryonic development, hair follicles transform and eventually develop into sebaceous glands, which are fully developed and substantial at birth. Sebum is a lipid that serves as a seal to prevent the skin from drying out. It is the primary byproduct of the sebaceous gland. The pilosebaceous canal serves as the principal conduit for sebum to transit from the sebaceous glands situated in the dermis to the epidermal surface. The sebaceous glands produce sebum, a substance that functions as a lubricant for hair and a protective barrier against harmful microorganisms. Sebum is a naturally produced oil that aids in preserving the moisture and suppleness of the scalp and hair. Excessive sebum production may result in the obstruction of hair follicles (Agarwal & Krishnamurthy, 2023).
11. Explain how the Dermal Papilla is attached to the hair and how it functions and works to make hair grow.
    Dermal papillae are an extremely dynamic cell population found in the dermal mesenchyme. The mesenchymal cells located in the dermal papilla of the hair follicle are responsible for regulating hair growth. The dermal papillae, located at the base of hair follicles, play a crucial role in the hair growth cycle by promoting the development of epidermal follicles, which is imperative for producing hair fiber. Preserving the potential hair inductivity of dermal papilla cells (DPCs) and dermal sheath cells is a critical factor in in vitro hair follicle formation and regeneration during cell culture (Taghiabadi et al., 2020).
     
12. Explain in detail about the blood vessels that are attached to the hair follicle and how they function to produce/interact with hair.
    The deep dermal vascular plexus supplies the hair follicle with blood as it grows. The blood arteries facilitate the provision of nutrients, elimination of waste, and promotion of development in the hair follicle. Hair follicles may die from a lack of blood flow in certain types of hair loss. Angiogenesis is also observed in anagen hair follicles. While the precise nature of the relationship between blood flow and the development, maturation, and maintenance of healthy hair follicles remains unclear, it is evident that adequate blood flow is a prerequisite for all three processes. The lymphatic vasculature in the dermis serves the dual purpose of nourishing the hair follicles and contributing to the skin’s immunological response.
13. Explain which nerves attach to the hair follicle and how they function to produce hair.
    The innervation of hair and hair follicles involves two distinct neural networks, each containing sensory and autonomic nerve fibers. The neural network in question comprises the area surrounding the hair follicle’s neck and comprises sensory C fibers and sympathetic fibers. The former refers to the A-delta fibers that traverse the entire length of the hair follicle. At the same time, the latter pertains to the C fibers that encircle the center of the follicle, situated between the isthmus and the sebaceous gland. The nerves in close proximity provide innervation to the proximal arrector pili muscles. The arrector pili muscle functions as a rope to maintain the integrity of the hair’s sympathetic nervous system. The regulation of hair follicle stem cells is facilitated by vesicles containing norepinephrine, which are released from the sympathetic nervous system via synapse-like connections (J. Zhang et al., 2021).
14. Explain how hair is white and black at the same time.
    Individuals with iron deficiency anemia are more likely to have segmented heterochromia in the hair on their scalp (Sato et al., 1989). Segmented heterochromia in scalp hair is the medical term for this disorder. Heterochromia may be inherited or brought on by genetic mosaicism, chimerism, illness, or injury. Genetic mosaicism occurs when a person’s body has two or more genetically separate sets of cells.
15. Explain what is Pili annulati or Ringed hair?
    Pili annulati (PA) is a rare benign disorder that causes the hair to appear speckled and banded with alternating light and dark colors. Other names for this condition include “ringed” hair and “Morse alphabet” hair. This appearance is due to an amplified light reaction caused by the recurrent appearance of abnormal air-filled cavities inside the hair shafts of those with the condition. Affected individuals may be recognized by the halo appearance that appears around their hair. The pili annulati occurs within the broader class of hair shaft issues that are not linked to fragility. Although a few outliers have been reported, the disease is almost always thought to be inherited.
    
    An increase in hair fragility is not often associated with pili annulati. Hair growth and tensile strength are normal in affected individuals, although hair shafts with abnormalities seem more susceptible to weathering and may have minor surface flaws. Alopecia areata is the medical term for this hair loss. Extreme hair fracturing and breakage, as found in trichorrhexis nodosa, may indicate an increased sensitivity at the level of the light bands (Nam et al., 2017). Even though pubic, axillary, and beard hair may be affected by pili annulati, it more often affects the hair on the scalp (Teysseire et al., 2017).
16. Explain how white hair becomes white.
    A reduction in the number of pigment cells within a hair follicle will produce lighter-colored hair due to a decrease in melanin content. The number of pigment cells, which are accountable for melanin production, decreases with advancing age in humans. Various factors, including genetics, stress, and chemical treatments, may contribute to the condition of the hair(Kumar et al., 2018).
17. Explain how gray hair becomes gray.
    The graying of hair in individuals is typically not attributed to stress. In actuality, hair does not undergo a “turning” gray process. It is impossible to alter the hair's color once it has grown from a follicle. Unless the hair is artificially colored, a solitary strand of hair in shades of brown, red, black, or blond will maintain its natural color. Due to a decrease in pigment production by hair follicles as one age, there is an increased likelihood of hair regenerating as gray beyond the age of 35. Genetic factors may influence the onset of this condition.
    
    Although stress does not directly impact the color of individual hairs, it can trigger a medical condition called telogen effluvium. This condition accelerates hair shedding by approximately three times the normal rate. As hair growth persists despite the presence of the disease, alopecia does not pose a significant concern for baldness. If an individual in their mid-30s is encountering escalated hair loss and regrowth due to stress, it is likely that the newly grown hair will exhibit a gray hue. The phenomenon of fur graying induced by stress has been scientifically documented. The extent to which this factor contributes to hair graying and its relevance to human subjects remains uncertain (B. Zhang et al., 2020).
18. Explain how red hair becomes red.
    The development of red hair is attributed to a genetic variation that enables the body to produce a greater amount of one type of melanin and a lesser amount of another type in both skin and hair cells. The prevalence of red hair can be attributed to a mutation in the melanocortin 1 receptor (MC1R) gene. Individuals with this genetic mutation exhibit a production of pheomelanin, a yellow-red pigment, due to malfunctioning melanocortin receptors, which manifestsin red hair and fair skin (Sessler, 2015).
     
19. Explain how blond hair becomes blond.
    Individuals with lower production of eumelanin pigment typically exhibit lighter skin and hair coloration (Mengel-From et al., 2009). Eumelanin and pheomelanin are the two types of melanin that determine the pigmentation of hair follicles, resulting in various hair colors. The presence of higher levels of eumelanin results in darker hair, whereas lower levels of eumelanin lead to lighter hair. An individual can possess hair follicles of varying colors, and fluctuations in melanin levels can result in a modification of hair color over time.
20. Explain what a club hair is and how it is formed.
    Club hair refers to a fully matured and non-proliferating hair strand. The presence of club hairs during the process of hair growth is a common occurrence. During this period, the hair follicles enter a state of rest and decrease in size. The cessation of oxygen and nutrient supply to hair follicles results in the cessation of hair shaft growth. During this period, there is a deceleration in the synthesis of melanin, a pigment in the hair shaft. It is common for the bulbous tips of telogen hairs that have been shed to appear white due to the loss of pigment during the process (Fernandez Flores et al., 2019).
    Club hairs are characterized by a keratin bulb at the root tip, indicating full hair development. The hair bulb retains the hair within the follicle until it is shed, and the growth cycle restarts. The hair replacement process involves gradually displacing club hairs by newly growing hair from the follicles.
21. Explain what a bulge is in the hair follicle and how it is formed and works to produce hair.
    Throughout an individual’s lifespan, there is a continuous proliferation of epidermal cells, which are subsequently replaced by germinative cells originating from the basal layer (Rompolas & Greco, 2014). The cells are exfoliated from the epidermal layer of the skin. In contrast, the hair follicle undergoes a structured process of regeneration characterized by distinct phases of activity (anagen), regression (catagen), and rest (telogen). The stem cells in the hair follicle's bulge regulate the cyclical development and differentiation of various cell types that collectively produce a pigmented hair shaft. The region between the sebaceous gland orifice and the attachment site of the arrector pili muscles is commonly referred to as the bulge area (Joulai Veijouye et al., 2017).
     Adipose tissue-derived stem cells possess remarkable versatility and reproducibility. These cells give rise to hair, sebaceous glands, and keratinocytes. The region of a hair follicle in cycling, known as the bulge area, is distinguished by cells lacking morphological differentiation. This area also functions as the point of attachment for the arrector pili muscle.
22. Explain what a hair bulb is in the hair follicle and how it is formed and works to produce hair.
    The hair follicle comprises three distinct parts: the infundibulum, the isthmus, and the inferior section. The hair bulb refers to the enlarged dermal papilla and hair matrix located at the base of the hair follicle.
    Mesenchymal cells, located within the dermal papilla, are involved in regulating hair growth. The network of connective tissue also accommodates the blood arteries and nerve terminals responsible for transporting oxygen and nutrients to the hair follicle. The keratinocytes, comprising the hair matrix, are undergoing active division in the region above the dermal papilla. As the cells undergo division and upward migration, they undergo keratinization to produce the hair shaft. The region of active hair development is commonly recognized as the hair bulb, encompassing the dermal papilla and hair matrix (Martel et al., 2017).
23. Explain what makes hair curly.
    The form of our hair follicles, which is genetically determined, dictates whether our hair is straight or curly. The activities of follicles are inherently linked to the follicle's anatomy and the hair fiber's maturation beneath the scalp. The observable fiber above the scalp possesses physical (macroscopic) qualities supported by its mechanical characteristics. These mechanical characteristics are determined by the physical (micro- and nano-) structures that take on various shapes and have a distinct biochemical compositions (Cloete et al., 2019). Hair from an asymmetrical follicle tends to exhibit a curly texture due to its oval shape.
24. Explain what makes hair straight.
    Straight hair results from a concerted effort on the part of the cells in the hair follicle, which results in uniform hair development. The hairs here are round.
25. What does keratin do to your hair?
    Keratin, a crucial constituent of hair and feathers' highly intricate morphological architecture, is a prevalent element in hair care formulations. Regarding mass production, keratins are commonly obtained from non-human animal sources like chicken feathers, wool, and so on (Gupta et al., 2012).
    The protein keratin K31 in the hair cortex plays a crucial role in strengthening the hair shaft (Sinclair et al., 2012). Chemical hair treatments, including bleaching, can potentially weaken hair strands by penetrating deep into the hair fiber and breaking down keratin K31. The application of K31 treatment has the potential to notably enhance the diameter, tensile strength, and surface smoothness of chemically damaged hair.
26. Explain all the distorted hair follicles known…e.g., corkscrew, s-shaped, and u-shaped.
    Repeated lifting and compression of the follicle can cause deformation and result in crooked hair growth beneath the skin. It is advisable to exercise caution when tweezing or plucking hair to avoid potentially distorting the follicle. Hair follicle distortion can also be attributed to other factors. An example of this would be that scurvy is primarily caused by a deficiency in vitamin C. Symptoms of scurvy may include hair loss and the presence of “corkscrew hairs,” resulting from pinpoint hemorrhage around hair follicles.
27. Explain all the causes and treatments of ingrown hairs and the best way to remove them.
    In cases where a hair regrows after removal, it may become ingrown if its growth direction causes it to bend and penetrate the skin. This condition may be triggered by certain grooming methods such as shaving, tweezing, and waxing. The presence of small, tender nodules on the skin resulting from hair follicles growing inward can cause significant discomfort. This condition disproportionately impacts individuals of African descent with naturally curly hair.
    Ways to remove ingrown hairs:
• Circular washing with a soft toothbrush or washcloth.
• Removal with sterile tweezers or needle
• Exfoliation
• Ice or a cold compress.
• Tea tree essential oil.
• Avoiding tight, non-breathable clothing.
• Laser treatments
28. After a hair is removed (with a tweezer)…what happens inside the follicle?
    Temporary damage to hair follicles may occur when hair is extracted from the root. However, a new bulb will regenerate, and hair will regrow through the follicle. The act of plucking hairs elicits a response contingent upon the population density and dispersion of the extracted follicles.
    The translucent bulb becomes visible upon extraction of hair from the root. The root sheath, commonly called the hair’s growth segment, is situated above the bulb in a plucked hair. The size of the hair bulb upon plucking can indicate the developmental stage of the hair. The hair bulb undergoes thinning in aging individuals. Typically, there is minimal residual bulb structure present upon natural hair shedding.
29. Technically, when does a hair die? Is it when the hair detaches from the blood vessel, falls out or is taken out of the body?
    The telogen phase, or resting phase, precedes hair loss. This stage lasts for around a few months. After death, the hair remains held in place by the follicle for roughly three months. It has broken off from the follicular papilla, making its way outward and eventually falling off the scalp. When the anagen phase of new, younger hair starts, the older hair is pushed out and falls away. Only 14 percent of hair is immune to this regeneration phase.
30. Explain the Meissner corpuscles, Ruffini corpuscles, Merkel corpuscles and Pacinian corpuscles.
• The Meissner corpuscles are sensory receptors in the skin that transmit signals related to gentle touch, vibration, and light pressure. Meissner corpuscles are activated by dynamic deformation, detecting skin movement and object manipulation. Corpuscle found in the Papillary Layer that is Sensitive to Touch. Messiner is Round and in the Dermis.
• Ruffini corpuscles primarily detect skin elongation, motion, and finger location. These elongated, capsule-shaped specialized structures can be located in the subcutaneous layer and the connective tissues of tendons and ligaments. Corpuscle that is Sensitive to Heat. Ruffini is Threadlike and in the Dermis.
• Merkel corpuscles, specialized cells, are located beneath the epidermis, the outermost layer of the skin. These cells may process touch due to their proximity to sensory nerve endings. Corpuscle that is Sensitive to Light Touch and ONLY corpuscle in Epidermis. Merkel is Tree like…Free Nerve Endings.
• Pacinian corpuscles are capable of detecting vibrations and discerning delicate textures. The sense of proprioception depends on the activation of Pacinian corpuscles, also known as Vater-Pacini or lamellar corpuscles, which are specialized sensory receptors responsible for detecting vibrations and deep pressure. Although distributed throughout the body, their highest concentration is observed in the palmar and plantar regions. Corpuscle in Skin Sensitive to Pressure. Pacinian is Round in the Hypodermis.
• Krause - Corpuscle in Skin Sensitive to Cold. Krause is Round and found in the Middle Dermis.
31. Explain or define the following:
• Bleeding or Hemorrhage
  Hemorrhage occurs when a blood vessel ruptures and causes bleeding. Various factors may cause internal and external bleeding. Bleeding may vary in severity from being relatively harmless, like a bruise, to life-threatening, like bleeding in the brain.
• Bruising or Ecchymosis
  A bruise is called “ecchymosis” in the medical field. The broken capillaries beneath the skin cause the coloring, a bruise or contusion.
• Redness or Erythema
  A skin injury or other inflammatory disease may induce erythema or redness. Erythema manifests as a rash and may be brought on by the sun, an infection, or both.
• Swelling or Edema
  The excess fluid causes this condition. Most of the time, venous insufficiency or congestive heart failure is to blame. Edema is characterized by puffiness or swelling of the subcutaneous tissue, most often in the legs and arms.
• Heat – Warm to Touch
  It’s the medical term for when skin becomes heated when touched. Your skin may be feeling warm for a variety of reasons. Some examples of these symptoms include running hot or having more blood flow to the skin’s surface. Fever, allergic responses, and environmental factors are common triggers.
• Petechiae or Microhemorrhage
  When the (microscopic) capillaries that provide blood to the body's cells burst, it causes petechial hemorrhages. From the heart, the oxygenated blood passes via arteries of progressively decreasing diameters until arriving at the capillaries.
• Scabs – Crusts
  A scab is a hard, dry crust that grows over a cut or wound to protect it while it heals. When skin is damaged, a scab quickly develops. The platelets in your blood stick together and create a sloppy clot to stop the bleeding. The clot will dry into a scab.
• Pain
  Pricking, tingling, stinging, burning, or aching are all examples of this unpleasant sensation. Pain may be either severe or mild. It might be intermittent or persistent. Pain might be localized to a cbody partur body (e.g., your back, abdomen, chest, or pelvis) or widespread. In certain cases, pain is a useful diagnostic indicator.
• Numbness – Anesthesia
  Loss of sensation is what anesthesia refers to. Anesthetics are painkillers or numbing medicines. Anesthetics are drugs used before, during, and after medical procedures to prevent pain, reduce anxiety, and induce sleep. This allows for many medical treatments to be performed without cng any discomfort or agony to the patient.
• Infection
  Intrusion and proliferation of microorganisms within the body. The microorganisms might be anything from bacteria and viruses to yeast and fungus. All parts of the body are potentially susceptible to infection.
• Pitted Scars
  A pitted scar is a depressed scar extending beyond the skin's surface. When the skin cannot renew its tissue, a pitted scar results. Acne and chicken pox are common causes of pitted scars. They may also develop in response to mole excision.
• Keloid Scars
  A keloid scar is a hypertrophic scar that forms after an injury heals.
• Leaking Follicle or Weeping
  This is a severe skin infection that has spread to the hair follicle. Pus (abscess) gathers in a localized area. A furuncle is another name for it.
• Scar Tissue
  Scar tissue forms at an injured site as a cluster of cells and collagen.
   
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