bluuebunny/crossref_metadata_2025 huggingface dataset:
Smooth, Bumpy and Ghostly Rides: (Re)Viewing the American Landscape and Travel Imagery in Bill Morrison’s Night Highway (1990), The Death Train (1993), City Walk (1999) and Ghost Trip (2000)
Authors: Boczkowska Kornelia
Published: August 2023

In this paper I analyze various ways in which Bill Morrison’s travel films, Night Highway (1990), The Death Train (1993), City Walk (1999) and Ghost Trip (2000), tend to challenge the concept of the American landscape through the use of cinematic conventions traditionally associated with early cinema’s phantom rides as well as contemporary travel ride films and road movies. Particularly, I argue that Morrison’s experimental pictures, while simultaneously drawing on and playing with selected phantom ride, travel ride film and road movie tropes, exploit the dynamics between the spectator’s unique frontal perspective, visual mobilities and distant panoramic views as well as evoke a distorted experience of sensational and contemplative voyages, hence challenging panoramic perception and an idealized image of American (film) landscape intrinsically bound with the natural and technological sublime. To achieve this particular effect, the analyzed material incorporates such elements as deteriorated footage, manipulated travel imagery and image looping enhanced by atmospheric scores, slow and fast motion cinematography or more conventional traditions of abstract formalism.
Prototype for chemical analysis and process intensification that is useful for research and teaching
Authors: Leite Alisson Rodolfo , Lima Roberto da Rocha , Hernandez Leonardo Frois , Da Silva Maria Lúcia Pereira
Published: August 2023

This work describes the design, manufacturing and testing of a detection system useful to be applied with microTAS or other compact equipment, such as those needed for Process Intensification in Chemical Engineering. The detection is carried out by a Quartz Microbalance (QCM), based on Piezoelectric Quartz Crystals (PQC) of multiple frequencies, from tens of kHz to almost GHz. With this instrument, it is possible to detect particles and droplets in a gaseous flow, as well as vapors of volatile organic compounds. The system allows simultaneous measurement at five different points, and due to its modularity, such points can be positioned several centimeters apart from each other. The use in teaching is favored not only because of its low cost and modularity, and also due to its portability, i.e., its small size.
Reasons Patients Seek Ophthalmic Medical Certificates/ Reports at the Chukwuemeka Odumegwu Ojukwu University Teaching Hospital Amaku, Awka, Nigeria
Authors: Ochiogu Bernard Chukwunonyerem , Onwuegbuna Arinze Anthony , Apakama Akunne Ijeoma
Published: August 2023

Background: Medical certificates or medical reports are often requested by patients for varying reasons which include permission to absent from work, school or certain duties or as evidence of ill health or ocular injury.

Aim: To explore the reasons patients seek medical certificate/medical report at the Chukwuemeka Odumegwu Ojukwu University Teaching Hospital, Awka, Nigeria.

Methods: This is a retrospective hospital based study conducted at the Chukwuemeka Odumegwu Ojukwu University Teaching Hospital Awka. The case files of new patients seen at the Eye Unit of the hospital from January 2016 to December 2021were examined. Those who requested for medical certificates/reports were identified and relevant information were extracted for the study. The results were analyzed and presented with frequency tables.

Results: Out of the 4407 new patients seen, 290(6.6%) requested ophthalmic medical certificate. Among the 290 patients, 170 (58.6%) were males while 120 (41.4%) were females, with male to female ratio of 1.4:1. The age range was 9 years to 75 years, while the mean age was 35.9years. Obtaining tinted vehicle wind shield permit 49 (16.9%) was the most common reason for seeking ophthalmic medical certificate followed by voluntary retirement. Civil servants 75 (25.2%) constituted the most common group, followed by students/pupils 57(26.2%). Among those that applied, 214 (73.8%) were granted while 76 (26.2%) were not granted. Ninety seven (33.4%) cases had ocular morbidities of which  assault cases 19(19.6%) were responsible for most of the ocular morbidities. Refractive error was the commonest diagnosis and some people had more than one diagnosis. Most patients 221 (96.2%) had presenting visual acuity of 6/6 – 6/18. Four patients had presenting visual acuity of <3/60 in both eyes.

Conclusion: Ophthalmic medical certificates/reports are requested for many reasons by patients. While some reasons are genuine, others are not. It behooves the certifier to obtain proper information about the patient. The certificate/report should be accurate, not misleading and devoid of sentiments.
Statistical Properties of Buys-Ballot Estimates for Multiplicative Model with the Error Terms
Authors: Dozie Kelechukwu C. N. , Ibebuogu Christian C.
Published: August 2023

In this study, we discuss statistical properties of Buys-Ballot estimates for multiplicative model with their error terms. The aim of this study is to characterize the properties of the row, column and overall means and variances of the Buys-Ballot table for multiplicative model with the error terms. The properties of Buys-Ballot estimates in this study are used for (1) estimation of trend parameters (2) estimation of seasonal effect (3) choice of model for decomposition. The results indicate that (1)
the column variance (\(\hat{\sigma}^2_j\)) of the Buys-Ballot depends on the seasonal indices (\(S^2_j\)) of the jth seasons. (2) the model that best describe the pattern in the transformed series is additive. This further confirms that the appropriate model of the original series is multiplicative.
Study of Genetic Diversity for Rust Resistance and Yield Related Traits in F5 and F6 Populations of Bread wheat (Triticum aestivum L.)
Authors: Mohammadi Lina , Kumar Mukesh , Singh Vikram , Akbarzai Darya Khan
Published: August 2023

Aims: To study the variability for morphological traits and yellow rust resistance in the bread wheat.

Study Design: Randomized block design (RBD) at a 5% level of significance.

Place and Duration of Study: The study was undertaken in the Department of Genetics & Plant Breeding, CCS Haryana Agricultural University, Hisar during the 2018-2019 and 2019-2020 cropping seasons.

Methodology: A total of 210 F5 and F6 progenies from the cross WH711 (susceptible) x PBW698 (resistant) including parents were evaluated in a single row of 1m length and 11 different morphological traits were included in the study. Infector rows were planted and artificial inoculation (using spray method) was carried out under field conditions using Pst (Puccinia striformis) isolate as a source of inoculums.

Results: The analysis of variance was highly significant (P<0.01) for yield and its related components. In F5 and F6 generations, high to moderate PCV and GCV were recorded for harvest index, biological yield/plant, 1000-grain weight, grain yield/plant, number of spikelets/spike, and number of grains/spike. High heritability coupled with high genetic advance as a percent of mean was observed for the number of grains/spike, number of spikelets/spike, 1000-grain weight, biological yield/plant, harvest index, and grain yield/plant in F5 and F6 generations. The correlation coefficient studies revealed that grain yield/ plant is significantly correlated with all yield-attributing characters except with days to heading in F5 and plant height in F6 generation. The path analysis recommended that all the traits had maximum positive direct contribution towards grain yield/plant except plant height and days to heading in F5 and F6 generations. The 135 and 148 progenies showed no infection in F5 and F6 generations.

Conclusion: The presence of substantial variability has existed among the tested wheat lines and possibility of improving yield and other desirable traits through selection or hybridization. Phenotypic and genotypic correlation analysis showed a positive correlation of grain yield with important quantitative characters. Hence, improving one or more of these traits could result in a high grain yield/ plant.
Genetic Variability, Heritability, Genetic Advance and Cluster Analysis in Indian Mustard (Brassica juncea L. Czern & Coss.) Under Timely and Late Sown Conditions
Authors: Gupta Anuj , Chauhan Sugandh , Tyagi Sunil Dutt , Singh Satpal
Published: August 2023

Two sets of field experiments were conducted at Genetics and Plant Breeding Research Farm of Narendra Deva University of Agriculture and Technology Kumarganj, Faizabad(U.P.), India during Rabi 2014-15 with 30 diverse genotypes of Indian mustard including three checks (Kranti, Vardan and RGN-73) to assess the genetic variability, heritability  and genetic advance under timely (TS) and late sown (LS) conditions. The genotypes were evaluated for thirteen quantitative characters. The analysis of variance showed highly significant differences among the genotypes for all the characters. The maximum phenotypic and genotypic coefficient of variability was observed for biological yield plant-1 in timely sown condition while in late sown condition the maximum phenotypic and genotypic coefficient of variability was observed for seed yield plant-1. High heritability coupled  with high genetic advance was observed for biological yield plant-1 and seed yield plant-1 in both TS and LS conditions indicating the influence of additive gene effects. D2 analysis grouped the 30 genotypes into six clusters. The distribution of genotypes in both the environments was different. Maximum genotypes (11) were present in cluster II in TS while maximum genotypes (12) were present in cluster IV in LS. The maximum inter cluster distance was observed between clusters IV and VI in TS while in LS the clusters II and VI showed maximum inter cluster distance. Hybridization among the genotypes separated by high inter-cluster distance will result in most heterotic crosses.
Drug Counterfeiting: Key Factors Affecting Vulnerable People in the World
Authors: Sarkar Shambhu
Published: August 2023

Drug counterfeiting has been a major problem for the government and regulatory agencies since the beginning of the 20th century. Most of the drug counterfeiting reported is in countries where a high demand for drugs combines with poor surveillance, quality control, regulation, and education to make it easy for criminals and cartels to supply it to the market through illegal sources. These fake medications are frequently produced in hazardous conditions, with insufficient, excess, or no active ingredients, and/or by using potentially harmful and even fatal chemicals. Counterfeit drugs mostly affect vulnerable sections of society due to their social and economic conditions. Some critical factors, such as insufficient or no health insurance coverage, disparities with racial and ethnic minorities, government policies, low income, lack of education, and uncontrolled online pharmacies, tend to attract them towards counterfeit drugs. This article explains the key risk factors of counterfeit drugs operating in legal environments and reviews recent adverse cases in the pharmaceutical supply chain.
The Effect of the Climate Change Looming for Indian Summer Monsoon
Authors: Yadav Manisha
Published: August 2023

In recent years, with global temperature rise, extreme weather and climate events, especially high temperature heat waves, floods and droughts, occur more frequently.  Recent observational and simulation projections with paleoclimate research reported that monsoon rainfall would become uncertain in the forthcoming century. One of the major problem in predicting the ISM is the accumulation of uncertainties arising from the complex role of Anthropocene activities on the climate system. This, in turn, would result in indecisions in the projected Gross Domestic Product (GDP), sustainable growth, and economy. About 21% of the Indian GDP is contributed by Agriculture (arguably the backbone of India's Economy) which itself highly dependent on the spatial and temporal distribution of monsoon rainfall. This paper reviews the projection of the Indian Summer Monsoon (ISM) in looming climate change. Evaluating the uncertainties in future monsoon behavior predictions would facilitate informed decision-making while formulating strategies for a sustainable Economy and energy policy. Reliable predictions of future ISM in the context of climate change are required while formulating adaptation strategies for sustainable growth and water availability.
Green Synthesis of Cr-PTC-HIna Metal Organic Frameworks (MOFs) and Its Application in Methylene Blue Photocatalytic Degradation
Authors: Mahrunnisa Nur , Adawiah Adawiah , Aziz Isalmi , Zulys Agustino
Published: August 2023

Metal Organic Framework (MOF) is a material that serves as a photocatalyst for decomposing methylene blue pollutant. MOF can be constructed using several kinds of synthetic methods. This study aims to determine the alternative efficient and eco-friendly synthesis method of isonicotinic acid-modulated chromium perylene 3,4,9,10-tetracharboxylate MOF (Cr-PTC-HIna) using solvothermal, hydrothermal, sonochemical, and mechanochemical methods. FTIR analysis revealed that Cr-PTC-HIna was successfully fabricated only by solvothermal, hydrothermal, and sonochemical methods, yielding 40.68%, 44.27%, and 46.50%. Cr-PTC-HIna-ST, Cr-PTC-HIna-HT, and Cr-PTC-HIna-SC have band gap energies of 2.02, 2.02, and 1.98 eV, respectively. Cr-PTC-HIna-HT and Cr-PTC-HIna-SC with irregular shapes form agglomerations. Cr-PTC-HIna-SC had the highest surface area, pore volume, and pore size of 92.76 m2.g−1, 0.3947cm3.g−1, and 142.74 nm, respectively. Cr-PTC-HIna-SC has the highest percentage of methylene blue decolorization through adsorption of 61.843% and photocatalytic degradation of 25.635%. Sonochemical and hydrothermal showed potential as more eco-friendly methods than solvothermal in synthesizing Cr-PTC-HIna MOF. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
VIGS as a strategy to reverse aphid wing induction by Y‐satellite RNA of cucumber mosaic virus
Authors: Kim Hangil , Masuta Chikara
Published: August 2023

Y‐satellite RNA (Y‐sat) of cucumber mosaic virus upregulates the expression of the aphid ABCG4 gene, which promotes aphid wing formation. We used ABCG4 virus‐induced gene silencing (VIGS) to prevent the wing‐induction mechanism of Y‐sat and thus inhibited aphid wing formation. Of the aphids on plants with VIGS of ABCG4, only about 30% had wings, and 60–70% of the winged aphids were small and likely impaired in flying ability. In addition, we showed that double‐stranded RNAs (dsRNAs) and small RNAs were transferred from the plant to the aphid to adequately silence aphid genes. Supplying ABCG4 dsRNA by VIGS to aphids is thus a potential strategy to inhibit aphid wing formation.
Epidemiology of Skin Disease
Authors: Williams Hywel C.
Published: August 2023

In addition to describing the prevalence and morbidity, modern epidemiology offers one of the most direct methods for identifying the causes of skin diseases such as nicotinic acid causing pellagra or ultraviolet causing cutaneous squamous cell carcinoma. Identifying risk factors for skin disease can lead to effective prevention which is better than treating sick individuals who present after a long chain of pathological events. This chapter explains the importance of thinking in terms of a population diagnosis rather than individual diagnoses and how a public health approach may be effective for some skin conditions such as scabies. Extensive information on the global burden of skin disease is presented, which describes how skin disease is a leading cause of disability‐adjusted life years. The chapter concludes with a description of a needs assessment for planning appropriate and comprehensive skin care, along with a useful glossary, checklists and further reading resources.
Genetics and the Skin
Authors: McGrath John A.
Published: August 2023

The mass of new knowledge emerging from studies on the human genome is having a major impact on how we investigate and understand the molecular basis of human diseases. Although the principles of genetics that govern the modes of inheritance and patterns of disease remain important, new DNA sequencing tools are providing substantial novel insights into genetic susceptibility, disease causation and clinical variation. Understanding how the new genetics is changing clinical practice is fundamental to improving the management of patients with the vast number of skin diseases that are influenced by genetic variants, both common and rare.
Adverse Immunological Reactions to Drugs
Authors: Ardern‐Jones Michael R.
Published: August 2023

Drug hypersensitivity reactions have been the subject of great interest to immunologists for more than half a century, yet the precise molecular pathways involved in their pathogenesis remain elusive. Significant recent advances include the discovery that abacavir directly binds the HLA‐B*5701 MHC peptide groove, thereby altering the repertoire of self‐peptides that can be expressed in the major histocompatibility complex (MHC). This induces T‐cell‐mediated inflammation and the hypersensitivity syndrome. Human leukocyte antigen (HLA) associations with severe cutaneous adverse reactions have so far been shown for six different drugs. However, the link between HLA association and clinical phenotype is confusing, with carbamazepine hypersensitivity associated with both HLA‐B*1502 and HLA‐A*3101. Genetic studies show that the former only predisposes to Stevens–Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN), yet the latter associates with exanthems, systemic hypersensitivity and SJS/TEN. In TEN, multiple molecular mechanisms of keratinocyte death have been postulated, but two predominate: (i) FasL up‐regulation and induction of Fas‐mediated keratinocyte cell death; and (ii) cytotoxic granulysin production by T, NK and NKT cells. Whether these act independently or synergistically remains to be established.
Principles of Measurement and Assessment in Dermatology
Authors: Finlay Andrew Y.
Published: August 2023

Methods to measure skin disease may involve measurement of signs (the Psoriasis Area Severity Index and SCORAD (scoring atopic dermatitis)), symptoms (visual analogue scales, itch scores or the Psoriasis Symptom Inventory), the impact on quality of life (the Dermatology Life Quality Index, the Children's Dermatology Life Quality Index or Skindex) or the benefit that patients perceive they have received from treatment (the Patient Benefit Index). There are also objective methods, such as ultrasound, to measure skin thickness. Measurement techniques should be validated to ensure that they correctly measure what they set out to measure. Methods may be designed for use in a particular skin disease, or for use across dermatology.
Principles of Systemic Therapy
Authors: Tidman Michael J. , Smith Catherine H.
Published: August 2023

This chapter on systemic dermatological therapy aims to provide practising dermatologists with sufficient information about the most frequently used systemic medications to enable these to be used for treating skin disease to the maximum benefit and minimum detriment to their patients. The introduction covers general aspects of systemic therapy, including patient selection and education, risk reduction measures and the importance of good record keeping. Thereafter follows a detailed review of immunomodulatory and antimicrobial drugs, including antihistamines, antimalarial agents, azathioprine, ciclosporin, colchicine, dapsone, fumaric acid esters, glucocorticoids, hydroxycarbamide, methotrexate, mycophenolate mofetil, potassium iodide, protein therapies (biological drugs and intravenous immunoglobulin), retinoids, thalidomide, antibiotics, antifungal agents and antiviral drugs. The profile of each individual drug includes its pharmacological properties (formula and structure, pharmacodynamics, pharmacokinetics and, where relevant, pharmacogenetic aspects), potential adverse effects, contraindications, cautions, drug–drug interactions, pre‐treatment screening, dosage regimens, monitoring requirements and its range of licensed and off‐label dermatological usage.
Principles of Skin Surgery
Authors: Hussain S. Walayat , Motley Richard J. , Wang Timothy S.
Published: August 2023

With the increasing global burden of skin cancer, the role of surgery in the armamentarium of the clinical dermatologist has never been so important. This chapter introduces the reader to the fundamentals of dermatological surgery. For the novice, the chapter outlines the basics of skin surgery including relevant anatomy, biopsy techniques and the simple elliptical excision. A comprehensive review and guide to common suturing techniques used during skin surgery is also provided. For the more experienced dermatologist, in addition to Mohs micrographic surgery, advanced cutaneous reconstructive techniques including full‐ and split‐thickness skin grafts, and one‐ and two‐stage flaps are also discussed. Important safety aspects and complications associated with skin surgery are dealt with. The chapter also provides a comprehensive guide to the essential equipment necessary prior to embarking upon cutaneous surgery.
Principles of Phototherapy
Authors: McKenna Kevin , Ibbotson Sally
Published: August 2023

Phototherapy or ‘light therapy’ has been used to treat skin diseases since ancient times. Modern phototherapy uses specific wavelengths typically within the ultraviolet part of the electromagnetic spectrum, by means of treatment modalities including UVB phototherapy (narrow‐band UVB 311–313 nm), photochemotherapy (psoralen and UVA; PUVA), UVA‐1 phototherapy and extracorporeal photochemotherapy (photopheresis) to treat a variety of skin diseases. The most frequently treated skin diseases include psoriasis, eczema, cutaneous T‐cell lymphoma (CTCL; mycosis fungoides), vitiligo and various photodermatoses. Narrow‐band UVB is the most commonly used phototherapy and is the phototherapy of first choice for most indications. PUVA is used mainly for UVB phototherapy treatment failures and in specific conditions, such as palmoplantar pustulosis, pustular psoriasis and pityriasis rubra pilaris. UVA‐1 is particularly useful for the treatment of sclerotic skin conditions such as morphoea and for atopic eczema. Photopheresis is indicated for the severe forms of CTCL: Sézary syndrome and graft‐versus‐host disease. The main short‐term hazard of UV therapy is burning of the skin and the primary long‐term concern is of skin cancer risk. Systemic PUVA is associated with a dose‐related increased risk of squamous cell carcinoma. No evidence of increased risk of skin cancer has yet been shown for UVB or UVA‐1 phototherapy. To avoid adverse events, careful patient selection, education and assessment of skin cancer risk is important. In addition, accurate dosimetry and UV lamp maintenance is required. Patient and staff safety is of paramount importance and is ensured by the establishment of good clinical governance pathways.
Viral Infections
Authors: Sterling Jane C.
Published: August 2023

Skin disease due to viruses may be a primary infection of the epidermis or may arise secondary to systemic infection. Depending on the virus, the effects may be necrotic damage of the infected cells, proliferation and tumour formation or inflammation without major skin cell damage. The features of DNA and RNA virus infections and their skin manifestations are covered in this chapter.
Fungal Infections
Authors: Hay Roderick J. , Ashbee H. Ruth
Published: August 2023

This chapter discusses the principles of medical mycology together with an introductory section on pathogenesis and the methods used to diagnose fungal infections. These are then set in the context of human fungal infections affecting the skin. The more common superficial mycoses such as dermatophyte andCandidainfection are included together with the rarer subcutaneous mycoses such as sporotrichosis and the deep and systemic infections. The main HIV/AIDS‐related conditions are covered from diagnosis to treatment. The treatment regimens are summarized using simple algorithms and there is a useful glossary of the mycological terms used in the chapter.
Psoriasis and Related Disorders
Authors: Burden A. David , Kirby Brian
Published: August 2023

Psoriasis encompasses a group of related immune‐mediated inflammatory skin diseases that affect up to 3% of the population. These diseases are heritable and over 40 genetic susceptibility loci have been identified, many of which are involved in antigen presentation, cytokine signalling or innate antimicrobial responses. The commonest presentation of psoriasis is plaque psoriasis but the disease is clinically hetereogeneous in its manifestations and natural history depending on the age of the patient, environmental triggers and the sites affected. Distinct but related phenotypes include psoriatic arthritis, palmoplantar pustulosis and generalized pustular psoriasis. Psoriasis is associated with co‐morbidities including obesity, diabetes, vascular disease, depression and inflammatory bowel disease, which contribute to the considerable morbidity and increased mortality. Treatments include topical agents for disease of limited extent, phototherapy (UVB, PUVA) and systemic therapy (methotrexate, ciclosporin, acitretin, fumarates) for more extensive disease, and biological treatment (tumour necrosis factor α inhibitors, ustekinumab) for severe resistant psoriasis.
Pityriasis Rubra Pilaris
Authors: Chu Anthony C.
Published: August 2023

Pityriasis rubra pilaris (PRP) comprises a group of clinically similar papulosquamous dermatoses, the underlying pathogenesis of which is only just beginning to be unravelled. They initially present with erythematous hyperkeratotic perifollicular papules that tend to coalesce into plaques but may progress to erythroderma, particularly in adults. The distribution, age of onset and speed of onset differ markedly between patients and these differences have been used to classify PRP into a number of clinically distinct subtypes. Using candidate gene screening, investigators have identified heterozygous gene mutations in
CARD14
, an activator of nuclear factor κ light chain enhancer of activated B cell (NFκB) signalling, which is implicated in other inflammatory diseases. In addition to coverage of conventional therapies such as acitretin and methotrexate, the place of biological agents, in particular ustekinumab, in managing these disorders is discussed.
Lichen Planus and Lichenoid Disorders
Authors: Piguet Vincent , Breathnach Stephen M. , Le Cleach Laurence
Published: August 2023

Lichenoid disorders are inflammatory disorders characterized clinically by flat‐topped, papular lesions and histologically by a lymphocytic infiltrate with a band‐like distribution in the papillary dermis. This group of conditions includes lichen planus, lichen planopilaris, lichen nitidus and keratosis lichenoides chronica, among others.
Eczematous Disorders
Authors: Ingram John R.
Published: August 2023

Eczema, also known as dermatitis, is a clinical and histopathological pattern of skin inflammation, which presents as pruritus, skin dryness and erythema. This chapter covers the non‐atopic eczema subtypes, which can be classified based on aetiology and skin site. The main subtypes are: nummular dermatitis, asteatotic eczema, hand eczema, venous eczema of the lower legs, eyelid eczema, juvenile plantar dermatosis and miscellaneous eczematous dermatoses. Eczema may result in skin lichenification and severe eczema is the commonest cause of erythroderma. Quality of life for patients and their families may be considerably reduced and occupational issues may add to the financial consequences. Management of non‐atopic eczema involves the avoidance of any external causes, where relevant, and treatment modalities that are similar to those for atopic eczema, in the context that relatively few clinical trials have been performed for non‐atopic eczema.
Seborrhoeic Dermatitis
Authors: Wakelin Sarah
Published: August 2023

Seborrhoeic dermatitis is a common, chronic, inflammatory dermatosis that has a predilection for the scalp, facial creases and large flexures including the ano‐genital area. It affects adults of all ages and often runs a relapsing course. A short‐lived infantile variant is also recognized. The cause is unclear, but increasing evidence supports a pathogenic role for lipophilicMalasseziayeasts, which comprise part of the normal skin microbiome. Most affected individuals are healthy, but seborrhoeic dermatitis may be a presenting feature of HIV infection, so at‐risk individuals should be tested. Treatment is aimed at reducing scalp yeasts and/or the inflammatory response, with topically applied imidazole antifungal drugs, mild potency corticosteroids and calcineurin antagonists.
Recurrent Angio‐Oedema without Weals
Authors: Grattan Clive E. H. , Maurer Marcus
Published: August 2023

Angioedema without weals may be either hereditary or acquired. Hereditary angioedema (HAE) is mediated by bradykinin and requires completely different assessment and treatment to acquired mast cell mediator‐induced angioedema. It is inherited as an autosomal dominant disorder. Types I and II are due to mutations in
SERPING1
, resulting in deficient or non‐functional C1‐esterase inhibitor (C1INH), respectively. HAE with normal C1INH (type III HAE) is associated with gain‐of‐function mutations in
F12
in about 20% of patients; no genetic mutation has been identified in the other patients and C1INH is normal. About 10% of patients with chronic spontaneous urticaria will present with mast cell mediator‐induced angioedema without weals, thus it is much commoner than HAE. The assessment and treatment is similar to that for patients with urticaria with weals. Acquired angioedema is mediated by bradykinin when it is due to angiotensin‐converting enzyme inhibitors or C1INH deficiency resulting from consumption of C1INH or its inactivation by autoantibodies. Acquired bradykinin‐mediated idiopathic angioedema, a rare condition, appears to be non‐mast cell mediator induced in a few patients. The entity is poorly defined as there is no diagnostic test but these patients may respond to tranexamic acid.
Immunobullous Diseases
Authors: Schmidt Enno , Groves Richard
Published: August 2023

The immunobullous disorders represent a group of conditions characterized by an antibody‐mediated autoimmune response against structural elements of the skin resulting in blistering of the skin and mucosae. Antibody targets include proteins in hemidesmosomes and the basement membrane zone (pemphigoid group), anchoring fibrils in the papillary dermis (epidermolysis bullosa acquisita), desmosomes (pemphigus group) and epidermal transglutaminase (dermatitis herpetiformis). If left untreated, immunobullous disorders may be associated with significant morbidity and mortality so prompt, accurate diagnosis and treatment are mandatory. Therapeutic options include systemic corticosteroid therapy, steroid‐sparing immunosuppressants (e.g. azathioprine and mycophenolates) and immunomodulating agents (e.g. dapsone and tetracyclines). In severe and/or refractory patients, intravenous immunoglobulin, immunoadsorption and the anti‐B‐cell drug rituximab are applied.
Lupus Erythematosus
Authors: Goodfield Mark , Dutz Jan , McCourt Collette
Published: August 2023

Lupus erythematosus (LE) is a complex spectrum of disease, involving one or multiple organ systems, and characterized by humoral and cellular autoimmunity, resulting in combinations of skin, joint, vascular and internal organ involvement. Skin disease occurs in the overwhelming majority of patients, and the patterns of skin involvement form an important part of subclassification, with localized discoid lupus usually being a single‐system manifestation, and acute cutaneous LE part of a potentially fatal multisystem disease. Intermediate forms, including subacute cutaneous LE are common and variable in their involvement of other organ systems. Ultraviolet exposure is an important disease precipitant. LE forms a major part of the group of disorders called connective tissue diseases, along with systemic sclerosis, localized and generalized morphoea, dermatomyositis, rheumatoid arthritis and Sjögren syndrome on the basis of clinical, pathological and immunological overlap.
Dermatological Manifestations of Rheumatoid Disease
Authors: Goodfield Mark
Published: August 2023

Whilst there are a number of specific connective tissue disorders with well‐recognized and diagnostic cutaneous features, there are other disorders with rheumatological features in which skin problems occur as part of the condition, but which are not necessarily diagnostic for the disease. These are sometimes less well described than those classic features of, for example, lupus erythematosus. Such conditions include rheumatoid arthritis and Sjögren yndrome, but also Still disease and rheumatic fever. The skin conditions seen in these diseases may involve the skin primarily, or the vasculature, but often present to dermatologists for diagnosis, usually in a patient known to have an underlying disease.
Cutaneous Amyloidoses
Authors: Schreml Stephan
Published: August 2023

Amyloids are common protein aggregates in nature. Some amyloids fulfil important biological tasks while others are known to cause diseases. Despite the fact that the ultrastructure of amyloid is highly conserved, the mechanism of amyloidogenesis remains a challenging research topic. In humans, amyloidoses can develop primarily in the skin, or systemic amyloidoses can lead to secondary cutaneous involvement. An accurate diagnostic procedure is crucial for planning therapy in this heterogeneous group of diseases. This chapter gives an overview of the different kinds of cutaneous amyloidoses as well as on diagnostic and therapeutic approaches. Furthermore, the contrast between functional and disease‐causing amyloid is discussed.
Cutaneous Porphyrias
Authors: Sarkany Robert P. E.
Published: August 2023

The porphyrias are a group of disorders caused by defects in the biosynthesis of haem. Their relevance to the skin arises from the phototoxic properties of the porphyrins, which accumulate in most porphyrias and cause photosensitivity. The majority of the porphyrias are inherited. Many of them affect other organs as well as the skin. The recognition and management of both the genetic and internal consequences of porphyrias presenting in the skin are a key challenge for the dermatologist. Clinical management in these disorders is made easier when the clinician understands their theoretical basis. Thus, this section is divided into two halves. The first provides a theoretical basis for understanding the porphyrias, the general principles of clinical management and a clinician's guide to laboratory testing. The second half covers individual porphyries in detail.
Calcification of the Skin and Subcutaneous Tissue
Authors: Bourke Johnny
Published: August 2023

Calcification occurs in the skin and subcutaneous tissues either as a consequence of the alteration of systemic calcium homeostasis or as a local side effect of inflammation, infection, trauma or neoplastic disease. In its most benign form, calcification is noticed as an incidental finding on histopathlogical analysis. The more severe forms, seen in scleroderma, dermatomyositis and calciphylaxis, lead to significant morbidity and mortality. The different forms of calcification are usually recognizable on clinical assessment. Further investigation, where clinically indicated, include biopsy, biochemistry and autoimmune serology. Excision is the most effective treatment for localized disease. Many different modalities are proposed for extensive disease and are often disappointing.
Xanthomas and Abnormalities of Lipid Metabolism and Storage
Authors: Flynn Paul D.
Published: August 2023

This chapter describes the various xanthomas that are the cutaneous manifestation of a number of primary and secondary dyslipidaemias. It includes an account of the relevant investigations of patients presenting with xanthomas, together with an outline of the dyslipidaemias and their management.
Skin Disorders in Diabetes Mellitus
Authors: Bourke Johnny
Published: August 2023

Many disorders are associated with diabetes, either directly or indirectly. Vascular damage, caused by an accumulation of advanced glycation end‐products, leads to leg ulceration, diabetic dermopathy and rubeosis. Neurological damage, due to damaged endoneurial microvessels, leads to the diabetic foot and foot ulcers. Bacterial and fungal infections are more common in diabetes. Obesity, insulin resistance and hyperlipidaemia lead to skin tags, acanthosis nigricans and eruptive xanthomas. A number of autoimmune and genetic disorders are more common in those with diabetes or predispose to diabetes, including thyroid disease, vitiligo, Cushing syndrome and autoimmune polyendocrine syndrome. In addition, a number of disorders of uncertain pathophysiology are linked to diabetes including necrobiosis lipoidica, cheiroarthropathy, scleredema diabeticorum and diabetic bullae.
Ectodermal Dysplasias
Authors: Itin Peter
Published: August 2023

Ectodermal dysplasias, a large group of heterogeneous heritable conditions, are characterized by congenital defects in two or more ectodermal structures, involving at least one in the hair (trichodysplasia), teeth (dental defects), nails (onychodysplasia) or sweat glands (hypohidrosis). Of the approximately 220 different ectodermal dysplasias, about 80 have been identified at the molecular level with the identification of the causative genes. Recent evidence implicates genetic defects in different key pathways orchestrating ectodermal organogenesis.
Genetic Defects of Nails and Nail Growth
Authors: Rubin Adam , Paller Amy S.
Published: August 2023

Hundreds of genodermatoses show changes of the nails, most commonly among the ectodermal dysplasias. Among the more common nail disorders are: (i) pachyonychia congenita, a group of disorders caused by mutations in one of five keratin genes expressed in the nail matrix, which also features painful plantar keratoderma; (ii) dyskeratosis congenita, characterized by telomerase shortening leading to nail dystrophy, oral leukoplakia and poikiloderma with a high risk of bone marrow failure; (iii) nail–patella syndrome resulting from mutations in the LIMX1b transcription factor that disrupt the development of the nails, patella, elbow, pelvis and kidneys; and (iv) hereditary anonychia, due to mutations inR‐spondin 4.
Genetic Disorders of Adipose Tissue
Authors: Millington George W. M.
Published: August 2023

Subcutaneous fat consists of two main groups of cells, white adipose tissue (WAT) and brown adipose tissue, as well as capillaries, which facilitate its metabolic functions. In adults, it comprises almost entirely WAT, where its functions include insulation, energy storage and a recently recognized complex endocrine role. Excess energy is stored in WAT, which leads to obesity. Brown fat is most detectable in the neonate and its function appears to be quite different from that of WAT, particularly being involved in thermogenesis. Its role in the older child and adult is less clear. Disorders of adipose tissue can be divided principally into: disorders of distribution of fat, the lipodystrophies, lipoedema and fibroadipose hyperplasia, disorders of excessive generalized accumulation of fat (in other words obesity), tumours and inflammation (such as panniculitis). There is increasing evidence of a hereditary component in the pathogenesis of all of these conditions.
DNA
Repair Disorders with Cutaneous Features
Authors: Fassihi Hiva
Published: August 2023

The human genome is continually being damaged by a variety of sources (such as reactive oxygen species and ultraviolet and ionizing radiation). Cells have evolved a number of complex pathways (nucleotide excision repair, double strand break repair and mismatch repair) to recognize and repair this damage in actively transcribed genes. Defects in these pathways result in a number of disorders, many with skin involvement, commonly photosensitivity, cancer and premature ageing. Xeroderma pigmentosum (XP), Cockayne syndrome and trichothiodystrophy are caused by defects in the nucleotide excision repair. All three syndromes can show photosensitivity because of an inability to repair UV radiation‐induced DNA damage. However, they are clinically very heterogeneous and only patients with XP have an increased risk of skin cancer. Early accurate diagnosis, based on clinical features, assessment of DNA repair and genetic analysis, can significantly improve morbidity and mortality from skin cancers, and also enables appropriate genetic counselling and prenatal diagnosis.
Inherited Metabolic Diseases
Authors: Morris Andrew
Published: August 2023

Many inherited metabolic diseases have dermatological features. Characteristic findings include angiokeratomas, which are associated with several lysosomal storage disorders. Xanthomas occur in hyperlipidaemias, cerebrotendinous xanthomatosis, Niemann–Pick disease and glycogen storage disease type 1. Ichthiosis is found in steroid sulphatase deficiency, Sjögren–Larsson syndrome, Chanarin–Dorfman syndrome, Refsum disease, defects of cholesterol synthesis and some congenital disorders of glycosylation (CDGs). Cutis laxa is typical of other CDGs and Menkes disease. Photosensitivity occurs in the porphyrias, Hartnup disease and Smith–Lemli–Opitz syndrome. Hair abnormalities include alopecia (in biotinidase deficiency), hypertrichosis (in the mucopolysaccharidoses), trichorrhexis nodosa (in argininosuccinic aciduria) and pili torti (in Menkes disease).
Inherited Immunodeficiency
Authors: Niehues Tim , Gennery Andrew R.
Published: August 2023

Primary immunodeficiencies (PIDs) are inherited disorders resulting in defects in the immune system leading to increased susceptibility to infection, autoimmune diseases, autoinflammation and failure of the inflammatory response and/or lymphocyte apoptosis as well as an increased susceptibility to neoplasia. Commonly, PIDs present with cutaneous infections or non‐infectious skin manifestations – some are mainly characterized by their dermatological presentation. PIDs are classified as combined immunodeficiencies with or without associated or syndromic features, predominantly antibody deficiencies, diseases with immune dysregulation, congenital defects of phagocyte number and function, defects in innate immunity, or autoinflammatory or complement disorders. The most prevalent of these primary immunodeficiencies are discussed.
Pruritus, Prurigo and Lichen Simplex
Authors: Ständer Sonja , Greaves Malcolm
Published: August 2023

Chronic pruritus (of more than 6 weeks duration) is one of the most frequent and burdensome of symptoms, occurring not only in association with a variety of dermatoses but also in other medical specialities, such as neurology, gynaecology and psychiatry. Prurigo nodularis and lichen simplex are characterized by a vicious circle of repeated scratching and pruritus, and represent cutaneous reaction patterns with a high negative impact on patients' quality of life. During the past two decades, new insights have been gained on specific neurons, receptors and mediators that are exclusively involved in the mediation of pruritus and not of pain. Diagnostic work‐up of chronic pruritus, prurigo nodularis and lichen simplex is challenging and time‐consuming, and management of the conditions remains difficult and unsatisfactory. The mainstays of treatment to date are antihistamines, anticonvulsants and certain antidepressants. Better understanding of the underlying pathophysiology of pruritus has enabled novel treatment approaches that target the pruritus‐specific mechanisms. Current knowledge on treatment is summarized for the first time in the European Guideline on Chronic Pruritis.
Mucocutaneous Pain Syndromes
Authors: Zakrzewska Joanna M. , Bewley Anthony
Published: August 2023

The mucocutaneous pain syndromes (MCPs) typically involve the head, neck and mouth. Genital dysaesthetic syndromes (vulvodynia, vestibulodynia, penoscrotodynia) are also common and are discussed in this chapter, as well as in specific genital chapters. For many MCPs no organic cause for their disease can be identified (with the exception of post‐herpetic neuralgia and trigeminal trophic syndrome), and the causes are thought to be related to the complex physiological interaction between the cranial and peripheral nervous systems and the brain itself. It is therefore essential that organic differential diagnoses for MCPs are excluded before a firm diagnosis is established. The management of patients with these diseases is often complex. There is a growing body of evidence that these patients are best managed in specialist, multidisciplinary clinics.
Acquired Pigmentary Disorders
Authors: van Geel Nanja , Speeckaert Reinhart
Published: August 2023

Abnormal skin pigmentation represents a common skin problem which may be congenitally determined or acquired during life. The former are discussed in Chapter [70]. Acquired pigmentary disorders encompass a broad range of diseases resulting not only in abnormal melanin pigmentation of the skin but also in skin colour change produced by a variety of other endogenous and exogenous pigments. The first part of this chapter examines the melanocyte and normal melanogenesis. The second part discusses not only acquired abnormalities of skin pigmentation resulting from disturbances in melanin pigmentation but also those disorders due to other endogenous or exogenous pigments. The third part describes acquired hypomelanosis including disorders with reduced pigmentation (hypopigmentation) and total absence of pigmentation (depigmentation). In the final part, non‐melanin pigmentation of the skin is examined.
Acne
Authors: Layton Alison M. , Eady E. Anne , Zouboulis Christos C.
Published: August 2023

Acne represents the commonest inflammatory dermatosis seen worldwide and is the leading reason for seeing a dermatologist; a number of acne variants are described. In children, these include neonatal, infantile, mid‐childhood and prepubertal acne. Acne fulminans and acne conglobata represent severe but rare forms. Predisposing factors may be implicated in acneform dermatoses; these include medications, occupational and environmental triggers, cosmetics, systemic diseases and syndromes. This chapter describes all clinical variants and provides evidence‐based or expert opinion on management.
Other Acquired Disorders of the Pilosebaceous Unit
Authors: Hay Roderick J. , Morris‐Jones Rachael , Jemec Gregor B. E.
Published: August 2023

This chapter includes descriptions of a number of non‐infective disorders involving the pilosebaceous unit that are not covered in other chapters.
Disorders of the Sweat Glands
Authors: Coulson Ian H. , Wilson Niall J. E.
Published: August 2023

In this chapter the anatomy, physiology and diseases of eccrine and apocrine sweat glands are described. The clinical patterns, causes and associations of excessive sweating as well as those of reduced or absent sweating are addressed in detail. Guidance is given on the management of hyperhidrosis and on the choice of appropriate therapy, including topical and systemic agents and surgery. The presentation and management of occlusive and inflammatory disorders of eccrine sweat glands is covered fully, as are the clinical features and management of abnormal sweat odour and colour and of apocrine miliaria. Brief reference is made to conditions associated with sweat gland inclusions.