Howard I Maibach

Howard I Maibach
University of California, San Francisco | UCSF

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1,757
Publications
269,513
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68,982
Citations
Citations since 2017
5 Research Items
15481 Citations
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201720182019202020212022202305001,0001,5002,0002,500
201720182019202020212022202305001,0001,5002,0002,500
201720182019202020212022202305001,0001,5002,0002,500

Publications

Publications (1,757)
Book
Full-text available
Thousands of international medical graduates come to the United States to start their career as physicians. Many of them, however, are not aware of the challenges and problems that they may encounter along the way. These difficulties can range from the language and cultural barriers to a lack of confidence and self-esteem. Many students are also un...
Article
Topical corticosteroid therapies are widely utilized, despite the controversial results of corticoid therapy in irritant contact dermatitis as a local inflammatory reaction after repeated or single skin exposure to a chemical substance. Although corticoids may reduce the inflammatory response to the irritant, their antiproliferative effects may red...
Article
Sensitive skin syndrome is a widely reported complaint but a diagnostic challenge because of its subjective symptoms and lack of clearly visible manifestations. Epidemiological studies have shown the prevalence of sensitive skin to be as high as 60–70% among women and 50–60% among men. Patients with this syndrome usually have unpleasant sensations...
Chapter
While human skin is an important external feature which can distinguish people of different ethnicities, less clear is how variations in human skin pigmentation may contribute to differences in skin structure, function, and pathophysiology. An understanding of differences in pigmentation, skin structure, and function becomes more important for trea...
Article
Background: Although there are several case reports of wet wipe-associated contact dermatitis, the prevalence of wipes as a source of allergic contact dermatitis in larger populations and the responsible allergens are largely unknown. Objective: The aim of the study was to determine the prevalence of wet wipes as a source of contact allergy and...
Chapter
As the proportion of the elderly in the United States increases steadily, the costs of treating cutaneous disorders also rise. Proliferative disorders of the skin are particularly common in the aged, and the risk of malignancy increases with age with possible catastrophic consequences. Nonmalignant proliferative disorders (e.g., skin tags, seborrhe...
Article
Interaction between drug and proteins and lipids in stratum corneum (SC) is an important pharmacokinetic parameter in early steps of absorption. Previous in vivo studies showed that the total amount of compound, regardless of properties, penetrating over a 96 h period could be predicted by the amount present in SC 30 min after application by a line...
Article
This review summarizes historical aspects, clinical expression and pathophysiology leading to coining of the terms atopy and atopic dermatitis, current diagnostic criteria and further explore the possibility of developing quantitative diagnostic criteria of atopic dermatitis (AD) based on the importance of atopic features - subjective, objective, a...
Chapter
While human skin is an important external feature which can distinguish people of different ethnicities, less clear is how variations in human skin pigmentation may contribute to differences in skin structure, function, and pathophysiology. An understanding of differences in pigmentation, skin structure, and function becomes more important for trea...
Article
Ethnic and socioeconomic (SES) disparities exist within healthcare. Specifically, minority group members experience more deleterious health outcomes than do majority group members. In this paper, we explore the factors that influence such variety, with a focus on the field of dermatology, in an attempt to understand ways to improve minority group r...
Article
Increased awareness of skin cancer and mosquito-transmitted diseases has increased use of insect repellents and sunscreens. The challenge in setting recommendations for use and reapplication, especially when used concomitantly, lies in finding the balance between applying a durable product effective in withstanding natural and physical factors such...
Article
Introduction: Dermatology is a relatively small field concerned with conditions of the hair, skin, nails and their related diseases; yet there is considerable active research and development within the field. Pharmaceutical companies seek more effective treatments through various therapeutic classes and delivery routes. However, 28 drugs have been...
Article
Skin decontamination is an important step mitigating percutaneous absorption through the stratum corneum (SC), which is also a highly complex process. Thus, understanding diffusion mechanisms and measuring dermal absorption rates are critical to protect humans from toxic exposures. Here, highly varied literature is placed in a biological and clinic...
Research
Full-text available
We conducted a study to evaluate the urogenital skin environment of pre-menopausal and post-menopausal women. Differences in biomolecular and physical measures of urogenital skin sites are reported in a separate publication, however, compelling observations on self-perceived sensitive skin, in light of the differences observed in the measured bioma...
Article
Postmenopausal hypoestrogenism often manifests as vulvovaginal atrophy. The labia shrinks, the introitus narrows, the vagina shortens, and the vaginal mucosa becomes more friable; vaginal pH rises, the microbiota composition is altered, and discharge becomes sparse. These atrophic changes cause vulvar and coital discomfort and also result in a high...
Article
Age-related changes occur in the function and basic structure of the skin and mucosa. With aging, the skin becomes drier, with more tendency to crack. It also becomes thinner, more fragile, and less resistant to infection. Loss of elasticity leaves it more susceptible to injury, while its ability to repair itself diminishes. Skin aging results in l...
Article
Full-text available
Serum concentrations of the sex steroids, which modulate skin structure and function, differ in aging men and women. Serum estradiol levels are unaffected by age in men, but in women, postmenopausal estrogen deficiency results in thinner, drier skin with a lower collagen content and reduced elasticity. Dehydroepiandrosterone and its sulfate form, p...
Article
Several studies have shown nickel and cobalt release from jewellery by using spot tests, but the metal composition of jewellery is largely unknown. To evaluate the metal composition of a large worldwide sample of mainly inexpensive jewellery items, and investigate the release of nickel, cobalt and lead from a subsample by using EN 1811:1998-require...
Article
At least 15 factors of percutaneous penetration exist that should be considered when investigating dermal absorption profiles of chemicals. Rubbing is one variable that has been understudied, but may play an important role in understanding overall exposure rates, chemical toxicity, dermal absorption and skin's barrier abilities. This reviews curren...
Article
Objective: Examine clinical trials performed for depigmenting agents in order to determine the most effective and well-tolerated depigmenting agent. Methods: We searched clinical trials, published and unpublished, performed for hydroquinone, ascorbic acid, azelaic acid, retinol and niacinamide in the period 2009 till present. Studies were examin...
Article
Full-text available
Cite this article: Farage M. A. et al. Possible Correlation between Self-Reported Sensitive Skin and Physical and Chemical Biomarkers. J J Expt Derm Res. 2015, 1(2): 010. We conducted a study to evaluate the urogenital skin environment of pre-menopausal and post-menopausal women. Differences in biomolecular and physical measures of urogenital skin...
Article
Animal models are used to predict human in vivo percutaneous absorption/penetration. Monkeys, pigs, rats, rabbits, guinea pigs, hairless rodents such as hairless rats, hairless mice, and hairless guinea pigs are among the animals most used for this purpose. Each animal model has its own advantages and weaknesses or limitations. Thus, we need to be...
Book
Full-text available
An era of global population aging is upon us. By 2030, one in eight people will be over age 65. Since women generally live longer than men, the health and welfare of postmenopausal women will become a significant public health concern. This book offers a comprehensive review of the life changes associated with menopause, both at the dermatological...
Article
Full-text available
Sex steroid hormones, estrogen, progesterone, and androgen play an important role in the gender-based pathophysiological differences observed in skin structure, function, and pathology. Age-related hormonal disturbances also have an impact on skin thickness, elasticity and moisture, skin aging, sebum production, and cellular immunity of the skin. P...
Article
The extensive procedure required to measure percutaneous absorption versus transepidermal water loss (TEWL) enhances the desire to find a correlation between the two measurements in order to more easily assess skin barrier function and should aid in the understanding and development of penetration enhancers. However, experiments investigating a qua...
Chapter
The application of drugs via the skin is appealing because it is non-invasive and avoids systemic side effects and numerous problems associated with conventional routes of drug application, i.e. intravenous or oral drug delivery (e.g. hepatic first pass, food enzymes, pH changes, etc.). In addition to this the rate of drug input can be controlled a...
Chapter
Chemical penetration enhancers have been studied for a long time as a means to increase the transport of a drug across the skin barrier. They exert their effect by using a range of mechanisms such as disrupting the lipid bilayer structure in the stratum corneum (SC) and thereby increasing the drug’s diffusion coefficient, extracting lipids from the...
Chapter
Skin as the main interface between body and environment is a functional barrier with unique anatomic and physiologic features. This chapter provides an overview of the key elements of skin structure including skin layers, appendages, and immunologic components. Protective properties of skin, absorption pathways, as well as methods for objective mea...
Chapter
Solar radiation, necessary for numerous physiologic processes in human skin, is a ubiquitous environmental stressor. Ultraviolet (UV), visible light, and infrared (IR), collectively referred to as optical radiation, are most relevant in human photobiology. Physiologic and pathologic processes occur with acute and chronic exposure to UV radiation,...
Article
The aim of the present study was to objectively quantify and predict bioavailability of three sunscreen agents (i.e., benzophenone-3, 2-ethylhexylsalicylate, and 2 ethylhexyl-4-methoxycinnamate) in epidermis treated by petrolatum and emulsion-based formulations for 7 and 30min on four human volunteers. Profiles of sunscreen agents through stratum c...
Article
Introduction: Onychomycosis, a common chronic fungal infection affecting fingernails and toenails, globally may affect 10 - 30% of the population. This chronic disease is difficult to eradicate. The goal of developing a highly effective and safe topical treatment has not yet been reached as it depends on the type of onychomycosis and the variety o...
Article
Full-text available
Background: Allergic contact dermatitis is common in children. Epicutaneous patch testing is an important tool for identifying responsible allergens. Objective: The objective of this study was to provide the patch test results from children (aged ≤18 years) examined by the North American Contact Dermatitis Group from 2005 to 2012. Methods: Thi...
Article
Full-text available
Unlabelled: BACKGROUNDS/OBJECTIVES: Cathepsin D plays an important part in maintaining a normal skin barrier. Our previous study found that cathepsin D decreased in chronic photodamaged skin. This study investigated the cathepsin D content change in the stratum corneum (SC) and the repairing role of cathepsin D in chronic photodamaged skin barrier...
Article
Full-text available
Context: Human/animal shaving biology. Objective: To assess the effect of shaving on percutaneous penetration and skin function. Methods: We screened 500+publications in Pub Med, Scopus, Cochrane Library and pertinent journals out of which only 17 were deemed relevant. Terms for searches included shaving and skin, percutaneous penetration and...
Article
Skin offers easy access, convenience and non-invasiveness for drug delivery and diagnosis. In principle, these advantages of skin appear to be attractive for critically ill patients given potential difficulties that may be associated with oral and parenteral access in these patients. However, the profound changes in skin physiology that can be seen...
Article
Full-text available
Abstract Nanotechnology is a rapidly expanding area of research involved in developing science-based solutions for innovative therapeutics. Silica nanoparticles (SNPs) have received wide attention in several industries and medicine and are being developed for biomedical and biotechnological applications such as drug delivery, DNA transfection, and...
Article
Abstract Dermal exposure is an important pathway in environmental health. Exposure comes from contaminated water, soil, treated surfaces, textiles, aerosolized chemicals, and agricultural products. It can occur in homes, schools, play areas, and work settings in the form of industrial sources, consumer products, or hazardous wastes. Dermal exposure...
Article
Background: Percutaneous penetration of urea in vivo in man has been documented. If urea can penetrate the skin, it may also move laterally. Lateral spreading of topical substances leads to unpredictable penetration dynamics and increased skin surface area exposure. Methods: The ability of urea, a low molecular-weight hydrophilic model, to penet...
Article
Background: Percutaneous penetration is a passive process that can occur following skin exposure to chemicals used in agriculture, industry, pharmaceuticals, cosmetics, and in the household. Once a penetrant is absorbed into the skin it may cause a local reaction or enter systemic circulation to produce widespread effects. Improved understanding o...
Article
Materials and methods: We conducted a thorough review of Pubmed search results for "textile percutaneous penetration" and "textile absorption". We also determined relevant articles that discussed percutaneous penetration of textiles into the skin and their associated disease states. Limitations: Due to limitations in current and past publication...
Article
Abstract Some natural sites, as a result of contaminants emitted into the air and subsequently deposited in soil or accidental industrial release, have high levels of organic and non-organic chemicals in soil. In occupational and recreation settings, these could be potential sources of percutaneous exposure to humans. When investigating percutaneou...
Article
Objective: This study aimed to examine the association between piercing and patch test sensitivity to metals (nickel, cobalt, and chromium) in North America. Methods: A retrospective analysis of 9334 patients tested by the North American Contact Dermatitis Group from 2007 to 2010 was conducted. Results: Nickel sensitivity was statistically ass...
Article
Unlabelled: Abstract Background: The stratum corneum has a wide variety of important functions, including host protection from foreign chemicals and bacteria, water loss prevention, and body temperature regulation. While water absorption studies on healthy intact skin are abundant, data on the percutaneous absorption of water in diseased skin are...
Article
Full-text available
Background: Cathepsin K (CatK), a cysteine protease with the potent elastolytic activity, plays a predominant role in intracellular elastin degradation in human dermal fibroblasts (HDFs), and contributes to solar elastosis. In previous studies, CatK expression was downregulated in photoaged skin and fibroblasts, but upregulated in acute UVA-irradi...
Article
Abstract Today's fragrances are present in more than just perfumes, having become ubiquitous in skin care products such as creams, shampoos, sun tan lotion and deodorants. While aromatics can arouse the senses, aromatic compounds applied to skin can also cause allergic contact dermatitis. This article describes diagnosis, limitations of patch testi...
Article
Objective: This study compared three model decontaminant solutions (distilled water, 10% distilled water and soap and methanol) for their ability to remove salicylic acid and aminophylline from an in vitro skin model. Materials and methods: Human abdominal skin was dosed with 20 µL of either [(14)C]-aminophylline or [(14)C]-salicylic acid on 1 c...
Article
Background Disperse dyes are well-known contact sensitizers. However, they are not included in the majority of commercially available baseline patch test series.Objectives To investigate the outcome of patch testing with a textile dye mix (TDM) consisting of eight disperse dyes at dermatology clinics in various countries.Patients/materials/methodsT...
Article
Allergic contact dermatitis is one of the most important dermatologic disorders worldwide - it can cause significant morbidity and decreased quality of life, as well as having major economic implications and loss of vocational productivity. Patch testing is the most important discovery in allergic contact dermatitis and the best diagnostic modality...
Article
Abstract This article describes how to identify allergic contact dermatitis resulting from hair dye, and outlines interventions and prevention principles for those who wish to continue dyeing their hair despite being allergic. Hair dye chemicals thought to be the most frequent sensitizers are discussed with instructions for health care providers on...
Article
Full-text available
Background Methylchloroisothiazolinone (MCI) and methylisothiazolinone (MI) are the active ingredients in commonly used preservative systems (e.g. Kathon CG®). MCI/MI is present in the European baseline patch test series at 100 ppm aq. Since 1986, 200 ppm (dose 0.006 mg/cm2) has been used in Sweden without causing skin irritation. Centres in Spain,...
Chapter
The viscosity is responsible for a covering effect which makes the simple passive washing more difficult, because the product sticks to the contact area (Fig. 4.1). A corrosive has, most often, a hydrophilic character. Mechanical washing can more or less remove hydrophilic viscous products, depending on their properties. However, viscous substances...
Article
Abstract The authors provide a framework for working up and counseling a patient with suspected textile dermatitis, focusing on identifying which textile materials are most likely to be the cause of the eczematous lesions, the current clinical guidelines, the utility and appropriateness of patch testing, the limitations of these guidelines, and our...
Article
Abstract The notion of treating the patient, and not the particular disease, has been emphasized by physicians for some time. In the past decade, this idea advanced with the human genome project, and has been taken further with the advent of personalized dermatology, or using genetics to drive pharmacological treatment. For example, recent melanoma...
Article
This in vitro investigation evaluated [14C] - d-methamphetamine hydrochloride ([14C]-meth HCl) transfer from contaminated vinyl tile (non-porous and smooth) and upholstery fabric (rough and loose) to human skin. 14C-METH HCL TRANSFER RATE FROM VINYL TO SKIN WAS RAPID; A CONTACT DURATION AS BRIEF AS 15 SECONDS RESULTED IN MEASURABLE RADIOACTIVITY IN...
Article
Full-text available
Symptoms without obvious physical cause are commonly reported in medical practice; when chronic, they can have a significant influence on patients' well-being. When traditional medicine is unable to provide relief, sufferers of such conditions often turn to alternative therapies. Western medicine has historically viewed the body through a silo mode...
Article
Full-text available
Despite the fact that women living in industrialized countries are likely to spend a third of their lives in menopause, the influence of the estrogen withdrawal associated with menopause on many body systems is not fully understood. This is particularly true of the immune system. Autoimmune diseases show a clear predominance in women, implying a ce...
Article
Full-text available
This paper summarises the proceedings of a recent workshop which brought together pharmaceutical scientists and dermatologists from academia, industry and regulatory agencies to discuss current regulatory issues and industry practices for establishing therapeutic bioequivalence (BE) of dermatologic topical products. The methods currently available...
Article
Mercaptobenzothiazole (MBT) and mercapto compounds are primarily used in rubber products. This study aimed to examine concomitant-positive rates of MBT (1% pet) and the 4-part mercapto mix (MM) (1% pet). This is a retrospective cross-sectional data from the North American Contact Dermatitis Group. A total of 30,880 patients were patch tested to MM...
Article
Carba mix (CM) contains 3 chemicals used as accelerators in manufacturing of rubber products and agricultural chemicals. Iodopropynyl butylcarbamate (IPBC) is a preservative used in industrial and personal care products. Potential cross-reactivity between these allergens is unclear. This study aimed to determine concomitant reaction rates between C...
Article
Onychomycosis, a common fungal infection of the nail, can have a substantial impact on quality of life. The success of topical therapy for onychomycosis depends on effective penetration, which can be enhanced using an appropriate delivery method. This study evaluated the effectiveness of a novel topical lacquer on enhancing [14C]-ketoconazole penet...
Article
Context: Occlusion is widely utilized to enhance the percutaneous penetration of applied drugs in clinical practice; however, occlusion does not increase the penetration of all chemicals. Objective: This study determines: (1) whether occlusion enhances the percutaneous penetration of the lipophilic salicylic acid or the hydrophilic formaldehyde...
Article
Both active and inactive ingredients in sunscreen may cause contact dermatitis. This study aimed to describe allergens associated with a sunscreen source. A cross-sectional analysis of patients patch tested by the North American Contact Dermatitis Group between 2001 and 2010 was performed. Of 23,908 patients patch tested, 219 (0.9%) had sunscreen c...
Article
Full-text available
p-Phenylenediamine (PPD) is the primary patch test screening agent for hair dye contact allergy, and approximately 100 different hair dye chemicals are allowed. To examine whether PPD is an optimal screening agent for diagnosing hair dye allergy or whether other clinically important sensitizers exist. Two thousand nine hundred and thirty-nine conse...
Article
Full-text available
Background Previous studies of epidermal kinetics in psoriasis have relied on invasive biopsy procedures or the use of radioactive labels. We previously developed a non-invasive method for measuring keratin synthesis in human skin using deuterated water labeling, serial collection of tape strips and measurement of deuterium enrichment in protein by...
Article
Abstract Accurate assessment of acne severity is essential for determining the appropriate treatment required. This paper reviews photographic methods for such assessment. Literature included met the following criteria: proposed photographic standards to assess acne, evaluated such standards, or offered photographic methods to improve visualization...
Article
Nail Apparatus Melanoma (NAM) is rare, particularly in Caucasians. Understanding its pathogenesis and collecting epidemiologic data may be difficult due to its location and the exiguity of the case series of this cancer. Cutaneous melanoma has been thought related to UV radiation, and NAM is considered an acral variant of melanoma, even if the nail...
Article
Tixocortol-21-pivalate (tixocortol pivalate) is used as a surrogate marker for contact allergy to hydrocortisone and other corticosteroids. To review the results of repeated open application testing (ROAT) and patch testing with hydrocortisone creams and ointments in tixocortol pivalate patch test-positive patients. ROAT was performed when the hist...
Article
Abstract Choroidal neovascularization membrane (CNVM) is a significant cause of ocular morbidity. Immunologic mechanisms have been proposed in the development of these lesions in exudative age related macular degeneration. Here, we describe the case of an 81-year-old man receiving ipilimumab, an immune modulating drug that enhances T cell response,...
Article
Full-text available
Context: Cutaneous toxicity is a frequent side effect of new anticancer targeted therapies. Skin reactions can severely impact the patient's physical, psychological and social well-being and may sometimes lead to discontinuations either treatment dose reductions. Objective: This study evaluates the impact of cutaneous adverse drug reactions (cAD...
Article
Context: Onychomycosis is a common fungal infection of the nail plate and bed that affects up to 14% of the population and can have a substantial impact on the quality of life of those affected. Objective: This study compared the onychopharmacokinetics, nail absorption, nail distribution, and nail penetration of [(14)C]-ciclopirox dissolved in n...
Article
BACKGROUND/PURPOSE: The stratum corneum serves as a main barrier for the skin, minimizing water loss and regulating absorption of substances. Because of its surface location, it is readily available for analysis. Consequently, many techniques are amenable to investigating its content and function. Here, we review the methods employed to evaluate th...
Article
This study assessed the bioequivalence, using keratolytic efficacy, of topical preparations studied in humans using adhesive tape stripping and biophysical methods. Ten healthy patients (3 men and 7 women [7 Caucasians and 3 Asians] mean age, 47 years) completed the study. Each coded product was randomly applied to the back according to the designa...
Article
Transdermal drug delivery is a multifactorial process with variable penetration mechanisms. Adverse effects associated with nonsteroidal anti-inflammatory drugs’ (NSAIDs) use in treatment for joint and muscle diseases are sufficiently severe to consider topical application. A drug's lipophilicity, fraction unbound and permeability found in the viab...
Article
Full-text available
Abstract Erlotinib is a targeted anticancer therapy with selective inhibitory activity for tyrosine kinase of the epidermal growth factor receptor (EGFR). Different skin reactions have been described linked to these drugs. There are no other reports about erlotinib-induced leukocytoclastic vasculitis (LV) in the erlotinib-bevacizumab regimen for bo...
Article
Context: Skin occlusion influences percutaneous penetration by limiting penetrant evaporation, but also through impeding loss of water from skin and increasing the hydration state of the stratum corneum, thus dramatically altering the physiological nature of the stratum corneum. In general, occlusion is widely utilized to enhance penetration of ap...
Article
BACKGROUND: Climates of the world are diverse and produce changes in skin integrity and functioning. Evidence on skin and its response to severe climates is limited, but information can be inferred from data characterizing skin under controlled climate conditions using noninvasive bioengineering techniques. METHODS: A literature search was conducte...
Article
Objective: To characterize the profile of application site reactions (ASRs) for patients treated with the buprenorphine transdermal system (BTDS) in chronic pain studies. Methods: The incidences of ASRs during treatment with BTDS were examined using (a) integrated data from 16 controlled and uncontrolled Phase III chronic pain studies (N = 6566)...
Article
Since the advent of World War II, governments and laboratories have made a concerted effort to improve prophylactic and therapeutic interventions counteracting cutaneously directed chemical warfare agents (CWA), and by inference, common industrial and consumer dermatotoxicants. In vitro percutaneous penetration assays, first utilized by Tregear in...
Article
Cutaneously directed chemical warfare agents can elicit significant morbidity and mortality. The optimization of prophylactic and therapeutic interventions counteracting these agents is crucial, and the development of decontamination protocols and methodology of post dermal exposure risk assessments would be additionally applicable to common indust...
Article
Background: Patch testing is an important diagnostic tool for determination of substances responsible for allergic contact dermatitis. Objective: This study reports the North American Contact Dermatitis Group (NACDG) patch testing results from January 1, 2009, to December 31, 2010. Methods: At 12 centers in North America, patients were tested...
Article
Full-text available
Skin prick testing is an essential test procedure to confirm sensitization in IgE-mediated allergic disease in subjects with rhinoconjunctivitis, asthma, urticaria, anapylaxis, atopic eczema and food and drug allergy. This manuscript reviews the available evidence including Medline and Embase searches, abstracts of international allergy meetings an...