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HAIR AND SCALP

Structure and chemical composition of hair

The hair on our bodies has a particular structure and is divided into thin and thick hair. Thin hair, also called lanugo or vellus, is located on all skin surfaces except for the palms of the hands and the soles of the feet. Thick hair, also called terminal hair, is dark and located only in some areas such as the scalp, the armpits, the pubic area, the beard area in the case of men, etc...

Structure of hair

Hair is located in the hair follicle, a particular skin structure with a sac-like form, tilted by approximately 75° with respect to the skin's surface. The lower part of the hair follicle is located in the deeper part of the dermis but its depth level varies from hair to hair (in the case of hair on the head, the average depth is around 0.6 -1 cm).
The sebaceous gland is attached to the upper third of the hair follicle. The hair follicle and sebaceous gland together are called the pilosebaceous unit. The arrector pili muscles of the hair are located on andanchored to the sebaceous glands, on the outer wall of the follicle. Inside the hair follicle we can note the following: it emerges from the skin's surface through an opening called an ostium; there is a narrowing in the upper third called the shaft; it also features a portion between the ostium and the shaft, called the infundibulum, a portion located between the shaft and lower part of the arrector pili muscles, called the bulge and finally a part underneath the bulge called the hair root.

In the center of the root, at the base of the follicle, is a loop facing upward and containing connective tissue full of blood vessels, lymphatic vessels and nerves, called the papilla, which is responsible for support, nourishment and endocrine control of the cells in the hair matrix.
Inside the follicle structure, proceeding from the outer layer inwards, we can note: the connective tissue sheath (full of nerve endings and consisting of concentric and longitudinal layers of collagen fibers with numerous fibroblasts); the vitreous membrane (a direct continuation of the cutaneous basement membrane); the external epithelial root sheath (direct continuation of the deeper layers of the epidermis that deepen as it follows the vitreous membrane); the internal epithelial root sheath (made up of three cellular layers, in direct contact with the outermost layer of the hair shaft).

Structure of hair

The hair structure of an adult is divided into three parts: shaft, root and bulb. The shaft is the visible, outer part of the follicle, with an average thickness of 65-78 microns in an adult. The root, a part that is usually not visible, within the follicle itself, is located in the skin between the ostium of the follicle and the insertion point of the arrector pili muscles. The bulb, even deeper than the root and located at the base of the root of the hair follicle, contains two-three layers of cells undergoing fast reproduction in its lower part: these constitute the matrix. The matrix cells are the only germinal cells. As they reproduce, the matrix cells push those born previously outward. As they emerge, the cells process the keratin going towards the "keratinization process", thereby becoming progressively more rigid. Immediately above the matrix cells are some melanocytes that are responsible for "coloring", pumping melanin into the cells that will become the hair "cortex".

By horizontally dissecting hair you can appreciate its structure, divided into three parts: the cuticle, the cortex and the medulla.
On the outside we find the cuticle consisting of a single layer of transparent thin cells, with a thickness between 0.2-0.5 microns, layered vertically at the level of the root and obliquely (similarly to scales) at the level of the shaft. Given its position, the cuticle is the first part to be damaged when hair is mistreated (via use of inadequate shampoo, perms, brushing, etc.).
The cortex is located at the intermediate level, and is the thickest part. It consists of thicker, spindle-shaped cells, 90 microns long and 5 microns wide, layered vertically in parallel rows. These contain a colored pigment called melanin, which tends to diminuish with age, thus making hair become "white" (process of going grey).
The medulla is located inside and consists of round cells, layered in columns, generally separated by air pockets.

In addition to water, the elements that compose the chemical composition of hair are: keratin, lipids, minerals and pigments.
Keratin is a protein found in the cortex. Keratin is composed of 18 amino acids. The most abundant amino acids are: Cysteine, cystine, serine, glutamic acid, glycine, threonine, arginine, valine, leucine and isoleucine.
Alpha keratin, fibrous and with a low sulphur content, is the protein we find in the greatest quantity in hair. It has a molecular weight of around 45,000 and is insoluble in water. Keratin may be deformed with water vapor ("styling").
The hair keratinization process is regulated by various elements (hormones, vitamins, genetic factors and metabolism) and is connected to the metabolism of cholesterol and its esterification with fatty acids synthesized by the epidermis. Dietary deficiencies and/or enzyme defects due to cholesterol and fatty acid synthesis may lead to irregular keratinization which results in structural defects in the hair shaft.
Lipids present in the hair's chemical structure are made up of triglycerides, waxes, phospholipids, cholesterol, squalene and free fatty acids. Quantifying these is extremely complex given that they are mostly derived from sebum.
Minerals and trace elements of the hair's chemical structure are an essential component of the protein-enzymatic systems. These are iron, magnesium, zinc, copper and lead.

Protein and/or electrolyte deficiencies in the hair's chemical structure may create hair problems and will become evident under the microscope due to the presence of a thin shaft associated with small bulbs. If the hair is structurally thin the bulbs will instead appear to be a normal size.
The pigments consist of melanin (colored substances), present in the hair in a diffused or granular form. These are not water soluble but they are soluble in strong acids and the color may be removed with hydrogen peroxide.
Melanocytes, using tyrosine (an amino acid that synthesizes protein) as a precursor, synthesize two main types of melanin: eumelanin, dark and present in black hair, and pheomelanin, lighter and present in golden, blonde and red hair.
The main chemical elements present in hair are composed of carbon (45%), oxygen (28%), nitrogen (15%), hydrogen (6.7%) and sulphur (5.3%).
Moreover, various trace elements are present (these can be found by performing a trace mineral analysis): Ca, Mg, Sr, B, Al, Si, Na, K, Zn, Cu, Mn, Fe, Ag, Au, Hg, As,Pb, Sd, Ti, W, Mo, I, P, Se. It is important to remember that the percentages of trace elements present in hair are subjective and vary in each individual.
Cystine is the main amino acid present in keratin (17.5%), followed by serine (11.7%) and glutamic acid (11.1%). Threonine, arginine and glycine are instead present in smaller percentages (approximately 6%).
80% of the weight of hair is due to the presence of protein (amino acid polymers), among which the main one is keratin, composed of 18 amino acids.
The main amino acids that make up keratin are: cystine (17.5%), serine (11.7%) glutamic acid (11.1%), threonine (6.9%), glycine (6.5%) and lastly arginine (5.6%).

Scientific collaboration between Professor Marco Toscani and Dr. Pasquale Fino, Chair of Plastic, Reconstructive and Aesthetic Surgery, Umberto I Health Center – “Sapienza” University of Rome.

Consent for marketing purposes
I, the undersigned, hereby give my consent to the processing and communication of my personal data so as to receive newsletters, commercial communications and/or advertising material via e-mail, post, text message and/or telephone regarding products or services provided by the Data Controller as well as the measurement of the degree of satisfaction relating to the quality of said services. The provision of such consent is optional

PRIVACY POLICY STATEMENT (Art. 13 of EU Regulation n. 2016/679 regarding personal data processing)

ADVIHAIR S.R.L., VAT N° 11495171008, with its offices at Via Benini n. 11 - 40069 Zola Predosa (Bologna, Italy), (hereinafter referred to as the, "Data Controller"), in its capacity as Data Controller, hereby informs you, in accordance with Art. 13 of EU Regulation n. 679/2016 (hereinafter referred to as, "GDPR") that your personal data (provided at the moment of subscription, by means of which business relationships deriving from the existing contract are established) shall be processed in compliance with the methods and for the purposes specified below. In accordance with the provisions of both the GDPR, Italian Legislative Decree n. 196/2003 and any subsequent amendments (hereinafter referred to as the "Privacy Code"), the processing operations carried out by the Data Controller, shall be based on principles of correctness, lawfulness and transparency and they shall be carried with the aim of complying with the principles of relevance, completeness, non-excessiveness while also safeguarding confidentiality.

The scope of data processing

Such data shall be processed, also by using IT and telematic procedures, with the acquisition, where necessary, of images, in accordance with the abovementioned legislation as well as any foreseen confidentiality obligations. More specifically, the personal data shall be processed by the centre, that will carry out all the necessary, individual processing operations ? collection, registration, organisation, storing, processing, modification, extraction, etc. as well as any other operation deemed useful with regards to the provision of the services requested.

Data processing purposes, Nature of data provision and consequences arising from the refusal to provide the requested data

1. Primarily, personal data shall be processed exclusively for purposes closely linked and instrumental to the fulfilment of contractual obligations to which you are party and that constitute the legal basis for the data processing itself in accordance with Art. 13, paragraph 1, letter c) of the GDPR. Such purposes particularly include:
- The conclusion of contracts for services and products provided by the Data Controller;
- The conclusion of contracts for services and products provided by the Supplier;
- Participation in presentation/courses/demonstration activities;
- The fulfilment of precontractual, contractual, administrative, and tax obligations arising from the existing business relationship established with you (requirements regarding operational, organisational, management, tax, administrative, insurance and accounting activities relating to the contractual and/or precontractual business relationship established);
- The fulfilment of obligations foreseen by law, by regulations, community legislation or by an order from a legal Authority (for example, with regards to anti-money laundering);
- The exercising of the Data Controller's rights, for example, with regards to the right to defence before a court. The processing of such data shall be carried out without the need for your express consent (Art. 6 letters b), c) of the GDPR) and the provision of such data is deemed as mandatory. In the absence of such provision, we cannot guarantee the establishment and execution of contractual relations with the Data Controller.
2. Secondarily, personal data may be processed only after obtaining your specific and explicit consent (Art. 7 of the GDPR) for the following purposes:
a) Marketing: to send you newsletters, commercial communications and/or advertising material via e-mail, post, text message and/or telephone, regarding products or services provided by the Data Controller as well as the measurement of the degree of satisfaction relating to the quality of said services.
b) The taking and use of portraits, photographic images and videos: the use and publication of portraits in photos and/videos that shall be taken, on the Data Controller's website and on its social network profile pages. For this purpose, the Data Controller hereby guarantees the fullest respect for rights relating to the honour and reputation of such data. The posing and use of the images are understood to be completely free of charge. The giving of one's consent with regards to Data Processing for Marketing purposes as well as for the use of the portrait, photographic image and video, for the abovementioned purposes and methods, is absolutely facultative and optional (and, in any case, such consent can be revoked without any formal procedure, also following the provision of services) and failure to provide such data shall not lead to any interference and/or consequences with regards to the abovementioned business relationship. In any case, also when the consent to authorise the Data Controller to carry out all the aforementioned operations has already been given, you shall be entitled to revoke such at any time whatsoever, by sending a registered letter regarding your "de-listing" and/or "image deletion" requests to the Data Controller's address as specified below. Following the receipt of such request, the Data Controller shall promptly remove and delete the relevant data from the databases used for Data processing for Marketing purposes and/or the use of the portrait, photographic image and video. The mere receipt of the de-listing request shall automatically be considered as a confirmation that such deletion process has been carried out.

Data Processing Methods

Data processing shall be carried out both manually (e.g. the collection of paper forms) and electronically or in any case, with the aid of appropriate electronic, IT and telematic tools so as to guarantee the security and confidentiality of the data itself, in accordance with what is stated in both Art. 32 of the GDPR and the Privacy Code. In any case, during the performance of data processing operations, all the necessary technical, IT, organisational, logistic measures and safety procedures shall be adopted, in order that the minimum level of protection of the data foreseen by law shall be guaranteed.

Duration of data processing

The Data Controller shall process the personal data for the necessary time so as to fulfil the aforementioned purposes and, in any case, for no longer than 10 years after the business relationship has ended, for the primary purposes and for no longer than 2 years after the need for data processing for Marketing Purposes has ended. The images shall be kept indefinitely and stored in the databases so as to have a historical memory of the events. Anyhow, a periodic verification is carried out relating to the obsolescence of the data stored in relation to the purposes for which they had been collected.

Categories of Individuals to whom the data may be communicated:

Your personal data may be communicated:
- To the Data Controller's employees in their capacity as persons in charge of data processing and/or internal data processors and/or system administrators;
- To self-employed professionals (lawyers, consultants, etc.), administrative and tax consultants for the necessary legal fulfilments, companies that carry out outsourcing activities on behalf of the Data Controller, in their capacity as appointed external Data Processors.
- To supervisory bodies, judicial authorities, insurance companies for the provision of insurance services, as well as those individuals to whom the communication of data is compulsory by law in order to carry out said purposes.
- For defensive investigations or to assert or defend one's rights before judicial courts, as long as it exclusively refers and is closely linked to such purpose.

Transfer of personal data

The Data Controller shall not transfer your personal data to a third-party country or to an international organisation.

Rights of the Data Subject

In your capacity as a data subject, you have rights in accordance with Art. 15 of the GDPR and more specifically, the right to obtain the confirmation from the Data Controller as whether or not personal data relating to you is being processed and, in which case, to obtain access to such personal data as well as the following information: a) the purpose of the processing; b) the categories of the personal data in question; c) recipients or categories of recipients to whom personal data has been or shall be communicated, in particular if these refer to third-party countries or international organisations; d) when possible, the foreseen period of retention of the personal data or, if this is not possible, the criteria used to determine such period; e) the right to ask the Data Controller to rectify or delete your personal data or the restriction of the processing of the personal data relating to you or to oppose to its processing; f) the right to lodge a complaint with a supervisory authority; g) if such data has not been provided by the data subject himself/herself, all the information available regarding its origin; h) the existence of an automated decision-making process, including profiling operations and, at least in such cases, significant information regarding the logic used, as well as the importance and the foreseen consequences of such processing for the data subject. Where applicable, you also have the faculty to exercise the rights pursuant to Articles 16-21 of the GDPR (the right to rectification, the right to be forgotten, the right to restriction of processing, the right to data portability and the right to object), as well as the right to lodge a complaint with the Italian Anti-trust Authority by following the procedures and indications published on said Authority's official website: www.garanteprivacy.it or alternatively, alternatively the right to lodge a complaint before a competent judicial authority.

Methods of exercising rights

You shall be able to exercise your rights at any time whatsoever by sending a registered letter to the Data Controller to such effect.

Data Controller

The Data Controller of the personal data you provided is: ADVIHAIR S.R.L., VAT N° 11495171008, with its offices at Via Benini n. 11 - 40069 Zola Predosa (Bologna, Italy) in the person of its Legal Representative. Articles from 15 to 22 of the GDPR are available by clicking on this link: http://eur-lex.europa.eu/legal-content/IT/TXT/HTML/?uri=CELEX:32016R0679&from=IT

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