Tolerability profile of topical cannabidiol and palmitoylethanolamide: a compilation of single-centre randomized evaluator-blinded clinical and in vitro studies in normal skin

BACKGROUND

An increasing number of studies have investigated the adverse effect profile of oral cannabinoids; however, few studies have provided sufficient data on the tolerability of topical cannabinoids in human participants.

AIM

To assess the tolerability profile of several commercial topical formulations containing cannabidiol (CBD) and palmitoylethanolamide (PEA) on the skin of healthy human participants.

METHODS

Three human clinical trials and one in vitro study were conducted. The potential for skin irritation, sensitization and phototoxicity of several products, were assessed via patch testing on healthy human skin. The products assessed included two formulations containing CBD and PEA, one containing hemp seed oil and four concentrations of CBD alone. Ocular toxicity was tested using a traditional hen's egg chorioallantoic membrane model with three CBD, PEA and hemp seed oil formulations.

RESULTS

There was no irritation or sensitization of the products evident via patch testing on healthy participants. Additionally, mild phototoxicity of a hemp seed oil product was found at the 48-h time point compared with the negative control. The in vitro experiment demonstrated comparable effects of cannabinoid products with historically nonirritating products.

CONCLUSION

These specific formulations of CBD- and PEA-containing products are nonirritating and nonsensitizing in healthy adults, and further encourage similar research assessing their long-term safety and efficacy in human participants with dermatological diseases. There are some limitations to the study: (i) external validity may be limited as formulations from a single manufacturer were used for this study, while vast heterogeneity exists across unregulated, commercial CBD products on the market; and (ii) products were assessed only on normal, nondiseased human skin, and therefore extrapolation to those with dermatological diseases cannot be assumed.

The global burden of atopic dermatitis: lessons from the Global Burden of Disease Study 1990-2017

BACKGROUND

The Global Burden of Disease (GBD) Study provides an annually updated resource to study disease-related morbidity and mortality worldwide.

OBJECTIVES

Here we present the burden estimates for atopic dermatitis (AD), including data from inception of the GBD project in 1990 until 2017.

METHODS

Data on the burden of AD were obtained from the GBD Study.

RESULTS

Atopic dermatitis (AD) ranks 15th among all nonfatal diseases and has the highest disease burden among skin diseases as measured by disability-adjusted life-years (DALYs). Overall, the global DALY rate for AD in 1990 was 121 [95% uncertainty interval (UI) 65·4-201] and remained similar in 2017 at 123 (95% UI 66·8-205). The three countries with the highest DALY rates of AD were Sweden (327, 95% UI 178-547), the UK (284, 95% UI 155-478) and Iceland (277, 95% UI 149-465), whereas Uzbekistan (85·1, 95% UI 45·2-144), Armenia (85·1, 95% UI 45·8-143) and Tajikistan (85·1, 95% UI 46·1-143) ranked lowest.

CONCLUSIONS

The global prevalence rate of AD has remained stable from 1990 to 2017. However, the distribution of AD by age groups shows a bimodal curve with the highest peak in early childhood, decreasing in prevalence among young adults, and a second peak in middle-aged and older populations. We also found a moderate positive correlation between a country's gross domestic product and disease burden. GBD data confirm the substantial worldwide burden of AD, which has remained stable since 1990 but shows significant geographical variation. Lifestyle factors, partially linked to affluence, are likely important disease drivers. However, the GBD methodology needs to be developed further to incorporate environmental risk factors, such as ultraviolet exposure, to understand better the geographical and age-related variations in disease burden.

Development of Patient Decision Aids for Plaque Psoriasis and Acne

INTRODUCTION

Despite proven benefits in other medical specialties, there is a paucity of patient decision aids (PDAs) in dermatology. The present study developed online PDAs for acne and psoriasis, incorporating iterative patient and physician feedback, in accordance with International Patient Decision Aid Standards (IPDAS).

DESIGN AND METHOD

Content was adapted from clinical practice guidelines and primary research and formatted for an 8th grade reading level. Feedback on content and format was obtained through focus groups with 15 psoriasis patients and survey with 34 acne patients. Feedback on presentation and clinical utility of the PDAs was gathered by survey from 51 physicians in Canada and the United States. Each data collection stage informed further development.

RESULTS

Demand for decision support, and satisfaction with the PDAs was high among patients. Physicians were approving of content and expressed a strong interest in PDA use.

CONCLUSION

Patients and physicians approve of the PDAs' content, format, and intended use. Online PDAs allow accessibility for patients and may reduce barriers to use for physicians.

Shared decision making and patient decision aids in dermatology

Shared decision making combines individual patient interests and values with clinical best evidence under the guiding principle of patient autonomy. Patient decision aids can support shared decision making and facilitate decisions that have multiple options with varying outcomes for which patients may attribute different values. Given the variable psychosocial impact of skin disease on individuals and relative uncertainty regarding best treatments and their adherence in many dermatological conditions, informed shared decision making, supported by patient decision aids, should constitute a central component of dermatological care.

The global burden of melanoma: results from the Global Burden of Disease Study 2015

BACKGROUND

Despite recent improvements in prevention, diagnosis and treatment, vast differences in melanoma burden still exist between populations. Comparative data can highlight these differences and lead to focused efforts to reduce the burden of melanoma.

OBJECTIVES

To assess global, regional and national melanoma incidence, mortality and disability-adjusted life year (DALY) estimates from the Global Burden of Disease Study 2015.

METHODS

Vital registration system and cancer registry data were used for melanoma mortality modelling. Incidence and prevalence were estimated using separately modelled mortality-to-incidence ratios. Total prevalence was divided into four disease phases and multiplied by disability weights to generate years lived with disability (YLDs). Deaths in each age group were multiplied by the reference life expectancy to generate years of life lost (YLLs). YLDs and YLLs were added to estimate DALYs.

RESULTS

The five world regions with the greatest melanoma incidence, DALY and mortality rates were Australasia, North America, Eastern Europe, Western Europe and Central Europe. With the exception of regions in sub-Saharan Africa, DALY and mortality rates were greater in men than in women. DALY rate by age was highest in those aged 75-79 years, 70-74 years and ≥ 80 years.

CONCLUSIONS

The greatest burden from melanoma falls on Australasian, North American, European, elderly and male populations, which is consistent with previous investigations. These substantial disparities in melanoma burden worldwide highlight the need for aggressive prevention efforts. The Global Burden of Disease Study results can help shape melanoma research and public policy.

Conflicts of interest in dermatology: a medical student and mentor perspective

Conflict of interest (COI) in medicine is well defined, but is seldom discussed in the field of dermatology. This perspective sheds light on this topic in dermatology and provides suggestions on how better to approach COI in medical school and residency.

A North American perspective on dermoscopy: benefits, limitations, and grey zones

Dermoscopy offers novel and cost-effective diagnostic information to guide patient care for melanocytic and non-melanocytic dermatoses. This article reviews the current use of dermoscopy, including its clinical benefits and limitations. Surveys of U.S. and Canadian dermatology residents have demonstrated a desire for improved dermoscopy teaching; an abundance of evidence calls for increasing its use in the clinical setting. Using the current evidence framework, North American dermatology training centers and professional societies should work to foster dermoscopy training and use by both dermatologists and other health care providers.

Clinical questions asked by medical students: a learning tool for dermatology rotations

BACKGROUND/AIMS

To determine whether having medical students answer self-generated patient-specific questions in a clinical setting promotes learning.

METHODS

Medical students rotating through dermatology clinics at the Denver Veterans' Affairs (VA) Medical Center were asked to formulate and answer one clinical question arising during patient encounters, and to complete a survey regarding their findings and experience.

RESULTS

49% (44/89) of rotating medical students completed the exercise. Self-generated questions frequently addressed therapy (61%, 27/44), prognosis (13%, 6/44), etiology/risk factors (7%, 3/44), and harm (5%, 2/44). The most frequently used sources of clinical information were journal abstracts/articles (55%, 24/44), UpToDate (50%, 22/44), websites (27%, 12/44) and printed textbooks (25%, 11/44). Medical students rated the impact of answers they obtained on a Likert scale of 1 (strongly disagree) to 5 (strongly agree) for the following: can be used to assist in patient's care (mean 4.1), improved care (mean 3.7), improved communication (mean 4.4), improved confidence in care (mean 4.2), improved knowledge (mean 4.6), and will improve future care (mean 4.5).

CONCLUSIONS

Medical students report increased knowledge, confidence and patient care skills after completing a self-directed formal exercise consisting of formulating and answering a patient-specific clinical question.

Cochrane Skin Group systematic reviews are more methodologically rigorous than other systematic reviews in dermatology

BACKGROUND

The Cochrane collaboration aims to produce high-quality systematic reviews. It is not known whether the methods used in producing Cochrane Skin Group (CSG) reviews result in higher quality reviews than other systematic reviews in dermatology.

OBJECTIVES

To determine how the methodological quality of dermatological CSG reviews published in The Cochrane Library and in peer-reviewed journals compare with non-Cochrane systematic reviews.

METHODS

Two blinded investigators independently assessed review quality using the 10-item Oxman and Guyatt scale.

RESULTS

Thirty-eight systematic reviews (17 Cochrane reviews published in The Cochrane Library, 11 Cochrane reviews published in peer-reviewed journals and 10 non-Cochrane reviews published in peer-reviewed journals) were examined. The Cochrane Library reviews included quality of life (11/17 vs. 1/10, P = 0.014) and adverse outcomes (14/17 vs. 2/10, P = 0.003) more often than non-Cochrane reviews published in peer-reviewed journals. Cochrane reviews published in both peer-reviewed journals and The Cochrane Library were more likely to include comprehensive search strategies (11/11 and 17/17 vs. 6/10, P-values = 0.04 and 0.01), take steps to minimize selection bias (11/11 and 16/17 vs. 3/10, P-values = 0.003 and 0.001) and appropriately assess the validity of all included trials (10/11 and 16/17 vs. 4/10, P-values = 0.04 and 0.007) than non-Cochrane reviews. Overall, Cochrane reviews published both in peer-reviewed journals and in The Cochrane Library were assigned higher quality scores by reviewers than non-Cochrane reviews (median = 6.0 and 6.5 vs. 4.5, P-values = 0.01 and 0.002).

CONCLUSIONS

The Cochrane Library systematic review methodology leads to higher quality reviews on dermatological topics.

Statins and fibrates for preventing melanoma

BACKGROUND

Effective treatment for advanced melanoma is lacking. While no drug therapy currently exists for prevention of melanoma, in vitro, case-control, and animal model evidence suggest that lipid-lowering medications, commonly taken for high cholesterol, might prevent melanoma.

OBJECTIVES

To assess the effects of statin or fibrate lipid-lowering medications on melanoma outcomes.

SEARCH STRATEGY

We searched the Cochrane Skin Group Specialised Register (February 2003), CENTRAL (The Cochrane Library Issue 1, 2005), MEDLINE (to March 2003), EMBASE (to September 2003), CANCERLIT (to October 2002), Web of Science (to May 2003), and reference lists of articles. We approached study investigators and pharmaceutical companies for additional information (published or unpublished studies).

SELECTION CRITERIA

Trials involving random allocation of study participants, where experimental groups used statins or fibrates and participants were enrolled for at least four years of therapy.

DATA COLLECTION AND ANALYSIS

Three authors screened 109 abstracts of articles with titles of possible relevance. We then thoroughly examined the full text of 72 potentially relevant articles. We requested unpublished melanoma outcomes data from the corresponding author of each qualifying trial.

MAIN RESULTS

We identified 16 qualifying randomised controlled trials (RCTs) (seven statin, nine fibrate). Thirteen of these trials (involving 62,197 participants) provided data on incident melanomas (six statin, seven fibrate). A total of 66 melanomas were reported in groups receiving the experimental drug and 86 in groups receiving placebo or other control therapies. For statin trials this translated to an odds ratio of 0.90 (95% confidence interval 0.56 to 1.44) and for fibrate trials an odds ratio of 0.58 (95% confidence interval 0.19 to 1.82). Subgroup analyses failed to show statistically significant differences in melanoma outcomes by gender, melanoma occurrence after two years of participation in trial, stage or histology, or trial funding. Subgroup analysis by type of fibrate or statin also failed to show statistically significant differences, except for the statin subgroup analysis which showed reduced melanoma incidence for lovastatin, based on one trial only (odds ratio 0.52, 95% confidence interval 0.27 to 0.99).

AUTHORS' CONCLUSIONS

The melanoma outcomes data collected in this review of RCTs of statins and fibrates does not exclude the possibility that these drugs prevent melanoma. There was a 10% and 42% reduction for participants on statins and fibrates, respectively, however these results were not statistically significant. Until further evidence is established, limiting exposure to ultraviolet radiation remains the most effective way to reduce the risk of melanoma.

A new method for manipulating transgenes: engineering heat tolerance in a complex, multicellular organism

BACKGROUND

Heat-shock proteins (hsps) are thought to protect cells against stresses, especially due to elevated temperatures. But while genetic manipulation of hsp gene expression can protect microorganisms and cultured metazoan cells against lethal stress, this has so far not been demonstrated in multicellular organisms. Testing whether expression of an hsp transgene contributes to increased stress tolerance is complicated by a general problem of transgene analysis: if the transgene cannot be targeted to a precise site in the genome, newly observed phenotypes may be due to either the action of the transgene or mutations caused by the transgene insertion.

RESULTS

To study the relationship between heat tolerance and hsp expression in Drosophila melanogaster, we have developed a novel method for transgene analysis, based upon the site-specific FLP recombinase. The method employs site-specific sister chromatid exchange to create an allelic series of transgene insertions that share the same integration site, but differ in transgene copy number. Phenotypic differences between members of this series can be confidently attributed to the transgenes. Using such an allelic series and a novel thermotolerance assay for Drosophila embryos, we investigated the role of the 70 kD heat-shock protein, Hsp 70, in thermotolerance. At early embryonic stages, Hsp70 accumulation was rate-limiting for thermotolerance, and elevated Hsp70 expression increased survival at extreme temperatures.

CONCLUSION

Our results provide an improved method for analyzing transgenes and demonstrate that, in Drosophila, Hsp70 is a critical thermotolerance factor. They show, moreover, that manipulating the expression of a single hsp can be sufficient to improve the stress tolerance of a complex multicellular organism.

CUSP/p63 expression in rat and human tissues

The human homolog of KET, p63, bears strong homology to the tumor suppressor p53 and plays an essential role in epithelial development. CUSP, the most abundant cutaneous product of p63, has been identified as an autoantigen in chronic ulcerative stomatitis (CUS). The original report of KET expression at least partially contradicts p63 expression subsequently reported by many different groups. We have examined p63 expression by Northern analysis of RNA from multiple human tissues and by indirect immunofluorescence of rat tissue with CUS patient sera. Northern analysis reveals p63 RNA in skin, thymus, placenta, skeletal muscle, kidney, and lung, with non-transactivating p63 RNA in skin, thymus, and placenta. Reverse transcriptase polymerase chain reaction (rtPCR) assays show abundant non-transactivating p63 RNA, and little to no transactivating p63 RNA, in human basal cell carcinoma as well as in normal skin adjacent to the tumors. p63 RNA expression was not detected in brain, heart, colon, spleen, liver, or small intestine. Immunofluorescence reveals p63 expression in skin, oral epithelium, tongue, kidney, and trachea, but not in liver, large intestine, testis, skeletal muscle, or heart. Focal p63 expression within tissues, the complex array of isoforms encoded by the gene, and the specificity of the probes and antibodies utilized, may all contribute to contradictory accounts of CUSP/p63 expression.

Erythema ab igne following heating/cooling blanket use in the intensive care unit

Erythema ab igne caused by chronic heat exposure presents as a net-like hyperpigmentation of the skin. We report this condition rapidly evolving due to the inadvertent use or dysfunction of an adjustable-temperature blanket in the intensive care unit. The use of heating/cooling blankets, especially in a patient with altered mental status, can result in iatrogenic erythema ab igne.

Characterization of an autoantigen associated with chronic ulcerative stomatitis: the CUSP autoantigen is a member of the p53 family

A unique clinical syndrome has been described in which patients have chronic oral ulceration and autoantibodies to nuclei of stratified squamous epithelium. We have characterized the autoantibodies from patients sera and found that the major autoantigen is a 70 kDa epithelial nuclear protein. Sequencing of the cDNA for this protein, chronic ulcerative stomatitis protein, revealed it to be homologous to the p53 tumor suppressor and to the p73 putative tumor suppressor, and to be a splicing variant of the KET gene. The p53-like genes, p73 and the several KET splicing variants, are recently described genes of uncertain biologic and pathologic significance. This study provides the first clear association of a p53-like protein with a disease process.

Preferential deadenylation of Hsp70 mRNA plays a key role in regulating Hsp70 expression in Drosophila melanogaster

Following a standard heat shock, approximately 40% of Hsp70 transcripts in Drosophila melanogaster lack a poly(A) tail. Since heat shock disrupts other aspects of RNA processing, this observation suggested that heat might disrupt polyadenylation as well. We find, however, that as the temperature is increased a larger fraction of Hsp70 RNA is polyadenylated. Poly(A)-deficient Hsp70 RNAs arise not from a failure in polyadenylation but from the rapid and selective removal of poly(A) from previously adenylated transcripts. Poly(A) removal is highly regulated: poly(A) is (i) removed much more rapidly from Hsp70 RNAs than from Hsp23 RNAs, (ii) removed more rapidly after mild heat shocks than after severe heat shocks, and (iii) removed more rapidly after a severe heat shock if cells have first been conditioned by a mild heat treatment. Poly(A) seems to be removed by simple deadenylation rather than by endonucleolytic cleavage 5' of the adenylation site. During recovery from heat shock, deadenylation is rapidly followed by degradation. In cells maintained at high temperatures, however, the two processes are uncoupled and Hsp70 RNAs are deadenylated without being degraded. These deadenylated mRNAs are translated with low efficiency. Deadenylation therefore allows Hsp70 synthesis to be repressed even when degradation of the mRNA is blocked. Poly(A) tail shortening appears to play a key role in regulating Hsp70 expression.

DEFICIENCY ANALYSIS OF THE TIP OF CHROMOSOME 3R IN DROSOPHILA MELANOGASTER

Region 98EF-100F in chromosome 3 is interesting for genetic analysis because it contains a number of genes of developmental importance. Although there are no preexisting simple deficiency stocks, this region is amenable to genetic manipulation using other types of rearrangements. In the present investigation we obtained deficiencies by combining the terminal deficiencies formed by segregation of Y;3 translocations with a series of duplications of the tip of 3R, both from Y;3 translocations with different breakpoints and from 3;1 duplications in which the 3R tip is carried as a second arm on the X chromosome. Analysis of such synthetic deficiencies reveals five haplo-abnormal loci in the 98A-100F interval. These include a haplolethal site, a newly described Minute and three previously reported Minute mutations. The newly discovered Minute has been designated M(3)99D and is localized cytologically to bands 99D1-9. The three previously reported Minute loci in the region have been localized more precisely: M(3)1 to bands 99B5-9, M(3)f to bands 99E4-F1 and M(3)g to region 100C-F. In addition, we have been able to obtain synthetic deficiencies uncovering all of the intervals from 99B5 to 100B. These deficiencies will be useful for future genetic and molecular analyses of the genes that map within the right tip of chromosome 3.