Depilatory double-disc mouse model for evaluation of vesicant dermal injury pharmacotherapy countermeasures

BACKGROUND

Sulfur mustard (SM) is a chemical warfare vesicant that severely injures exposed eyes, lungs, and skin. Mechlorethamine hydrochloride (NM) is widely used as an SM surrogate. This study aimed to develop a depilatory double-disc (DDD) NM skin burn model for investigating vesicant pharmacotherapy countermeasures.

METHODS

Hair removal method (clipping only versus clipping followed by a depilatory), the effect of acetone in the vesicant administration vehicle, NM dose (0.5-20 μmol), vehicle volume (5-20 μl), and time course (0.5-21 days) were investigated using male and female CD-1 mice. Edema, an indicator of burn response, was assessed by biopsy skin weight. The ideal NM dose to induce partial-thickness burns was assessed by edema and histopathologic evaluation. The optimized DDD model was validated using an established reagent, NDH-4338, a cyclooxygenase, inducible nitric oxide synthase, and acetylcholinesterase inhibitor prodrug.

RESULTS

Clipping/depilatory resulted in a 5-fold higher skin edematous response and was highly reproducible (18-fold lower %CV) compared to clipping alone. Acetone did not affect edema formation. Peak edema occurred 24-48 h after NM administration using optimized dosing methods and volume. Ideal partial-thickness burns were achieved with 5 μmol of NM and responded to treatment with NDH-4338. No differences in burn edematous responses were observed between males and females.

CONCLUSION

A highly reproducible and sensitive partial-thickness skin burn model was developed for assessing vesicant pharmacotherapy countermeasures. This model provides clinically relevant wound severity and eliminates the need for organic solvents that induce changes to the skin barrier function.

Effect of acetone fraction of Ottelia alismoides on the G2/M cell cycle arrest and apoptosis in the human carcinoma cell lines

ETHNOPHARMACOLOGICAL RELEVANCE

The North-eastern parts of India have immense therapeutic floras, Ottelia alismoides is an aquatic plant that has been in use for a long time in traditional medicine for treating diseases like cancer, tuberculosis, diabetes, febrifuge, hemorrhoids, and rubefacient. In lung and skin carcinoma cells with a high rate of proliferation and metastasis including drug resistance and non-specific target activity, generates important challenges towards their treatment strategy. Thus, finding novel therapeutic targets to treat lung and skin cancer progression is essential to enhance the patients' survival with treatment.

AIM OF THE STUDY

The purpose of this study was to evaluate the apoptotic potential of acetone extract of O. alismoides (L.) Pers. (OA-AC) and to identify the compounds responsible for this effect, HRLC-MS-QTOF analysis of the extract has been undertaken along with in-silico molecular docking analysis of the identified compounds.

MATERIALS AND METHODS

A549 and A431 cells were treated with acetone extract of O. alismoides (OA-AC) at 24 h and 48 h exposure and cell cycle phase distribution was evaluated and also apoptosis induction activity was evaluated by OA-EtBr staining and Mitochondrial outer membrane potential assay. Western blotting was performed for the evaluation of apoptotic protein expression. At last, the HR-LCMS of OA-AC was analyzed to identify the compounds responsible for the apoptotic activity of the extract.

RESULTS

The cell cycle phase distribution analysis in A549 and A431 cells at 24hrs exposure with 10 μg/mL and 25 μg/mL of OA-AC showed a potent arrest or blockage at the G2/M phase of the cell cycle with reduced expression of cyclin B and p-Cdc2. At 48 h exposure, apoptosis was observed in these cancer cells with elevated expression of Bax, p21 and cleaved caspase 3 and reduced expression of the Bcl2.

CONCLUSION

AO-EtBr staining of these cancer cells reveals that the death induced by OA-AC was apoptotic in nature with depolarization of mitochondrial membrane due to loss or damage of the mitochondrial membrane. The HRLC-MS-QTOF analysis of OA-AC depicted 14 major isolable compounds and molecular docking analysis displayed 4 compounds that might act as an inhibitor of cyclin B for G2/M phase arrest that leads to apoptotic induction in the cells.

Retinal injury mouse model and pathophysiological assessment of the effect of arsenical vesicants

The eye is ten times more vulnerable to chemical warfare agents than other organs. Consistently, exposure to vesicant arsenical lewisite (LEW) manifests significant corneal damage leading to chronic inflammation, corneal opacity, vascularization, and edema, culminating in corneal cell death. However, despite the progress has made in the research field investigating arsenical-induced pathogenesis of the anterior chamber of the eye, the retinal damage resulted from exposure to arsenicals has not been identified yet. Therefore, we investigated the effects of direct ocular exposure (DOE) to LEW and phenylarsine oxide (PAO) on the retina. DOE to arsenicals was conducted using the vapor cap method at the MRIGlobal facility or an eye patch soaked in solutions with different PAO concentrations at UAB. Animals were assessed at 1, 3, 14, and 28 days postexposure. Results of the study demonstrated that both arsenicals cause severe retinal damage, activating proinflammatory programs and launching apoptotic cell death. Moreover, the DOE to PAO resulted in diminishing ERG amplitudes in a dose-dependent manner, indicating severe retinal damage. The current study established a prototype mouse model of arsenical-induced ocular damage that can be widely used to identify the key cellular signaling pathways involved in retinal damage pathobiology and to validate medical countermeasures against the progression of ocular damage.

[ANALYSIS OF PATCH TEST RESULTS USING COCAMIDOPROPYL BETAINE-RELATED SURFACTANTS]

BACKGROUND

A few previous studies have compared the patch test (PT) results obtained using different types of PT units.

OBJECTIVES

This study aimed to compare PT results between the Patch Tester 'Torii' and Finn Chamber.

METHODS

Thirty-four patients with intractable scalp dermatitis were enrolled in this study. PT were performed with three kinds of amphoteric surfactants, cocamidopropyl betaine (CAPB), high-concentration CAPB (h-CAPB), and lauramidopropyl betaine (LAPB), using both the Patch Tester 'Torii' and Finn Chamber, and the changes in the subjects' symptoms after they stopped using these surfactants were examined.

RESULTS

Regarding the PT results for CAPB, h-CAPB, and LAPB, the results obtained with the Finn Chamber included a significantly lower frequency of irritant reactions (CAPB; p=0.003, h-CAPB; p=0.046, LAPB; p=0.002) than those obtained with the Patch Tester 'Torii'. However, there were no significant differences in the frequencies of positive reactions between the Patch Tester 'Torii' and Finn Chamber in each surfactant. The same tendency was seen in PT with LAPB (p=0.041) in 17 selected patients, who showed positive or doubtful reactions in PT performed with the surfactant-containing products they had used and whose symptoms 'markedly improved' or 'improved' after they stopped using these products. Among these surfactants, CAPB exhibited the highest positivity rate; however, the differences were not significant.

CONCLUSION

In patients with intractable scalp dermatitis, PT of the abovementioned surfactants performed using the Finn Chamber were superior to those conducted using the Patch Tester 'Torii' because they resulted in fewer irritant reactions.

Stress Drivers of Glucose Dynamics during Ozone Exposure Measured Using Radiotelemetry in Rats

BACKGROUND

Inhaled irritant air pollutants may trigger stress-related metabolic dysfunction associated with altered circulating adrenal-derived hormones.

OBJECTIVES

We used implantable telemetry in rats to assess real-time changes in circulating glucose during and after exposure to ozone and mechanistically linked responses to neuroendocrine stress hormones.

METHODS

First, using a cross-over design, we monitored glucose during ozone exposures (0.0, 0.2, 0.4, and 0.8 ppm) and nonexposure periods in male Wistar Kyoto rats implanted with glucose telemeters. A second cohort of unimplanted rats was exposed to ozone (0.0, 0.4 or 0.8 ppm) for 30 min, 1 h, 2 h, or 4 h with hormones measured immediately post exposure. We assessed glucose metabolism in sham and adrenalectomized rats, with or without supplementation of adrenergic/glucocorticoid receptor agonists, and in a separate cohort, antagonists.

RESULTS

Ozone (0.8 ppm) was associated with significantly higher blood glucose and lower core body temperature beginning 90 min into exposure, with reversal of effects 4-6 h post exposure. Glucose monitoring during four daily 4-h ozone exposures revealed duration of glucose increases, adaptation, and diurnal variations. Ozone-induced glucose changes were preceded by higher levels of adrenocorticotropic hormone, corticosterone, and epinephrine but lower levels of thyroid-stimulating hormone, prolactin, and luteinizing hormones. Higher glucose and glucose intolerance were inhibited in rats that were adrenalectomized or treated with adrenergic plus glucocorticoid receptor antagonists but exacerbated by agonists.

DISCUSSION

We demonstrated the temporality of neuroendocrine-stress-mediated biological sequalae responsible for ozone-induced glucose metabolic dysfunction and mechanism in a rodent model. Stress hormones assessment with real-time glucose monitoring may be useful in identifying interactions among irritant pollutants and stress-related illnesses. https://doi.org/10.1289/EHP11088.

SKIN FEATURES IMPORTANT FOR THE OCCURRENCE OF CONTACT DERMATITIS IN HEALTHCARE WORKERS

The occurrence of skin lesions in healthcare workers is associated with a negative impact on important skin functions, including protection from mechanical injuries, sunlight, dehydration, and penetration of chemical substances or pathogenic microorganisms. In healthcare professionals, the most common occupational skin disease is contact dermatitis (CD), either irritant (ICD) or allergic (ACD), and typically on the hands. ICD accounts for about 80% of occupational CD, making it the most frequent cause. According to the literature, CD frequency is higher among healthcare professionals than other occupations, with critical occupational risk factors including contact with irritants and allergens at the workplace. Furthermore, ICD is a multifactorial disorder influenced by many constituent and environmental factors. Constituent factors include age, gender, body location, atopy, and genetic factors, while environmental factors include temperature, airflow, humidity, and occlusion. Commonly encountered irritants are water, detergents and surfactants, solvents, oxidizing agents, acids, and alkalis; however, use of protective gloves or equipment, hand-washing habits, use of cleansers and creams, active inflammatory skin diseases, and daily activities are also important for ICD onset. Additionally, ICD is known to predispose to ACD. Important risk factors for ACD development include occupation, age, history of atopic dermatitis, genetics, female gender, and fair skin phototype. In summary, numerous skin features and other occupation-related factors contribute to CD among healthcare practitioners. Given the high level of exposure to contact irritants/allergens in the healthcare setting, implementation of preventive measures is crucial for a safer work environment.

Drimane Sesquiterpene Aldehydes Control Candida Yeast Isolated from Candidemia in Chilean Patients

Drimys winteri J.R. (Winteraceae) produce drimane sesquiterpenoids with activity against Candida yeast. In this work, drimenol, polygodial (1), isotadeonal (2), and a new drimane α,β-unsaturated 1,4-dialdehyde, named winterdial (4), were purified from barks of D. winteri. The oxidation of drimenol produced the monoaldehyde drimenal (3). These four aldehyde sesquiterpenoids were evaluated against six Candida species isolated from candidemia patients in Chilean hospitals. Results showed that 1 displays fungistatic activity against all yeasts (3.75 to 15.0 µg/mL), but irritant effects on eyes and skin, whereas its non-pungent epimer 2 has fungistatic and fungicide activities at 1.9 and 15.0 µg/mL, respectively. On the other hand, compounds 3 and 4 were less active. Molecular dynamics simulations suggested that compounds 1–4 are capable of binding to the catalytic pocket of lanosterol 14-alpha demethylase with similar binding free energies, thus suggesting a potential mechanism of action through the inhibition of ergosterol synthesis. According to our findings, compound 2 appears as a valuable molecular scaffold to pursue the future development of more potent drugs against candidiasis with fewer side effects than polygodial. These outcomes are significant to broaden the alternatives to treat fungal infections with increasing prevalence worldwide using natural compounds as a primary source for active compounds.

Comparison of two skin protection regimes for the Prevention of Incontinence-associated Dermatitis in geriatric care (PID): a study protocol for an exploratory randomised controlled pragmatic trial

INTRODUCTION

The majority of aged long-term care receivers and patients in geriatric acute care are affected by some form of incontinence. These individuals are at risk of developing incontinence-associated dermatitis (IAD), a common type of irritant contact dermatitis caused by repeated and prolonged direct contact of the skin with urine and stool. The prevalence of IAD in these settings is high. Preventive measures include mild skin cleansing and the application of skin protecting leave-on products. Available evidence is weak regarding the comparative performance of different skin protection strategies and products due to a lack of confirmatory trials using relevant comparators and endpoints. Therefore, the overall aim of this exploratory trial is to compare the effects of three skin protection strategies to estimate effect sizes of the recently published core outcomes in IAD research.

METHODS AND ANALYSIS

A pragmatic three-arm, assessor-blinded, randomised controlled, exploratory trial with parallel group design will be performed, comparing film-forming and lipophilic skin protecting leave-on products for IAD prevention with standard incontinence care alone. The trial will be conducted in geriatric nursing homes and geriatric acute care settings in the federal state of Berlin, Germany. A total of n=210 participants being incontinent of urine and stool will be included. Outcomes include IAD incidence, erythema, erosion, maceration, IAD-related pain, patient satisfaction, safety, feasibility and compliance. IAD incidence of the control and intervention groups will be compared to estimate effect sizes, and the procedural feasibility of the intervention will be tested to plan a possible subsequent confirmatory randomised controlled trial.

ETHICS AND DISSEMINATION

The study received the approval of the ethics committee of Charité-Universitätsmedizin Berlin (EA4/043/22). Results will be disseminated through peer-reviewed open-access journals and international conferences.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT05403762) and German Clinical Trials Register (Deutsches Register Klinischer Studien, or DRKS) (DRKS00028954).

RAB20 deficiency promotes the development of silicosis via NLRP3 inflammasome

Silicosis is a worldwide serious occupational disease that is caused by inhalation of silica crystals. However, little is known about the pathogenesis mechanism of silicosis. We performed single-cell sequencing in bronchoalveolar lavage fluid (BALF) from mine workers with silicosis and their co-workers who did not develop silicosis, and found that the RAB20 deficiency in monocytes/macrophages was strongly linked to the development of silicosis. In the silicosis murine model, RAB20 knockout markedly enhanced the silica crystal-induced pulmonary interstitial fibrosis and respiratory dysfunction. Moreover, this process is strongly accompanied by IL-1β release and NLRP3 activation. In vitro, RAB20 knockout macrophages aggravated the crystalline silica-induced IL-1β release and NLRP3 inflammasome activation partly by increased ratio of crystalline silica/phagosomal areas/volumes to induce lysosomal injury. Thus, these findings provide novel molecular insights into the intricate mechanisms underlying lysosomal protein RAB20 that are necessary for environmental irritant-mediated innate immunity, and shed light on the future development of novel therapy target for the prevention of silicosis.

[Irritant toxicity and lectin content of different processed products of Pinelliae Rhizoma]

The present study aims to investigate the correlation between irritant toxicity variation and lectin content variation during the processing of Pinelliae Rhizoma products and to explore the feasibility of Western blot as a method for the detection of lectin. We processed Pinelliae Rhizoma Praeparatum Cum Alumine, Pinelliae Rhizoma Praeparatum, and Pinelliae Rhizoma Praeparatumcum Zingibere et Alumine to different degrees and then analyzed their irritant toxicity via Draize rabbit eye test. Western blot was employed to determine the lectin content in Pinelliae Rhizoma products processed with different methods. The correlation between toxicity variation and lectin content variation was then analyzed. Different decoction pieces of Pinelliae Rhizoma were collected for the determination of lectin content. The three processed products of Pinelliae Rhizoma showed gradually decreased toxicity and lectin content as the processing continued. The decreasing trend of lectin content was consistent with that of irritant toxicity during processing, which indicated that the change in lectin content could reflect the trend of irritant toxicity. No band of lectin appeared in the Western blot of processed products of Pinelliae Rhizoma, which suggested that western blotting can be used for the detection of toxic lectin in the processed products of Pinelliae Rhizoma. Lectin should not be detected in the Pinelliae Rhizoma products processed according to the methods in the Chinese Pharmacopoeia.

Role of hair follicles in the pathogenesis of arsenical-induced cutaneous damage

Arsenical vesicants cause skin inflammation, blistering, and pain. The lack of appropriate animal models causes difficulty in defining their molecular pathogenesis. Here, Ptch1+/- /C57BL/6 mice were employed to investigate the pathobiology of the arsenicals lewisite and phenylarsine oxide (PAO). Following lewisite or PAO challenge (24 h), the skin of animals becomes grayish-white, thick, leathery, and wrinkled with increased bi-fold thickness, Draize score, and necrotic patches. In histopathology, infiltrating leukocytes (macrophages and neutrophils), epidermal-dermal separation, edema, apoptotic cells, and disruption of tight and adherens junction proteins can be visualized. PCR arrays and nanoString analyses showed significant increases in cytokines/chemokines and other proinflammatory mediators. As hair follicles (HFs), which provide an immune-privileged environment, may affect immune cell trafficking and consequent inflammatory responses, we compared the pathogenesis of these chemicals in this model to that in Ptch1+/- /SKH-1 hairless mice. Ptch1+/- /SKH-1 mice have rudimentary, whereas Ptch1+/- /C57BL/6 mice have well-developed HFs. Although no significant differences were observed in qualitative inflammatory responses between the two strains, levels of cytokines/chemokines differed. Importantly, the mechanism of inflammation was identical; both reactive oxygen species induction and consequent activation of unfolded protein response signaling were similar. These data reveal that the acute molecular pathogenesis of arsenicals in these two murine models is similar.

Laryngeal and pharyngeal actinomycosis: a systematic review and report of 3 cases

INTRODUCTION

Actinomycosis is a granulomatous infection that rarely involves the larynx or pharynx. Three cases of actinomycosis of the larynx or pharynx from our institution were reviewed and a systematic literature review was performed to better define surgical management, antibiotic therapy, risk factors, and incidence of recurrence or complications.

MATERIALS AND METHODS

PubMed/Medline, Cochrane, Embase, and Google Scholar were searched on November 30, 2021 using the terms "laryngeal actinomycosis", "pharyngeal actinomycosis", "actinomycosis AND larynx", and "actinomycosis AND pharynx." Articles which did not describe appropriate sites or were non-English were excluded. Results were collected for demographic information, site(s) of infection, comorbidities, lesion characteristics and treatments.

RESULTS

Along with three cases reported from our institution, 40 unique cases were reviewed from 37 studies for a total of 43 patients (Table 1). 34 (81.0 %) of the patients were male with the highest incidence of infection in the seventh decade (54.8 %). The most common site for the infection was the larynx (69.0 %) followed by the pharynx (16.7 %). Risk factors included a history of radiation therapy, immunosuppression, inhalational irritant, and diabetes (Table 3). The duration of antibiotic therapy varied greatly, from one month to one year and total follow up ranged from 1 month to 2.5 years (Table 1).

CONCLUSIONS

A comprehensive review of the literature on pharyngolaryngeal actinomycosis shows that this infection has increased prevalence within the head and neck cancer patient population. Similar to cervicofacial actinomycosis, these atypical sites have shown favorable responses to extended antibiotic therapy and generally do not require aggressive surgical management.

Earthworm half-pipe assay: A new alternative in vivo skin corrosion test using invertebrates

As a result of the efforts to introduce the principle of the 3Rs (replacement, reduction, and refinement) into animal testing, alternative in vitro skin corrosion test methods have been developed and standardized globally. However, alternative in vitro skin corrosion test methods have some limitations in terms of the use of humanely killed rats or commercial models and kits. The present study focused on the applicability of invertebrates as alternative in vivo skin models. Even though earthworm skin comprises the same biomolecules as human skin, the possibility of using earthworm skin as an alternative for skin testing remains unexplored. In this study, we developed a half-pipe tool for earthworm skin corrosion testing and optimized the test protocol. Subsequently, the applicability of the earthworm half-pipe assay for corrosion testing with six chemicals, including inorganic acids, organic acids, and alkalis, was investigated using stereomicroscopy and electron microscopy. It was observed that the specific concentrations for earthworm skin corrosion were lower than those for animal or in vitro tests. Therefore, the sensitivity of the earthworm half-pipe assay indicates that it could be useful as a screening tool before conducting in vivo animal tests or in vitro skin tests. This new method can contribute to research on alternative skin corrosion tests by reducing ethical issues, time, and cost while achieving effective results.

Nicotine Exerts Cytotoxic Effects in a Panel of Healthy Cell Lines and Strong Irritating Potential on Blood Vessels

The use of tobacco products is a major global public health issue, as it is the leading cause of preventable death worldwide. In addition, nicotine (NIC) is a key component of electronic and conventional cigarettes. Although nicotine’s addictive potential is well known, its health effects are not entirely understood. Thus, the main objective of the present study was to evaluate its toxicological profile both in vitro, at the level of three healthy cell lines, and in ovo, at the level of the chorioallantoic membrane. Five different concentrations of nicotine were used in keratinocytes, cardiomyocytes, and hepatocytes for the purpose of evaluating cell viability, cell morphology, and its impact on nuclei. Additionally, the hen’s egg test on the chorioallantoic membrane (HET-CAM) method was used to assess the biocompatibility and irritant potential of the chorioallantoic membrane. Across all cell lines studied, nicotine was proven to be significantly damaging to cell viability, with the highest concentration tested resulting in less than 2% viable cells. Moreover, the morphology of cells changed dramatically, with alterations in their shape and confluence. Nicotine-induced cell death appears to be apoptotic, based on its impact on the nucleus. In addition, nicotine was also found to have a very strong irritating effect on the chorioallantoic membrane. In conclusion, nicotine has an extremely strong toxicological profile, as demonstrated by the drastic reduction of cell viability and the induction of morphological changes and nuclear alterations associated with cellular apoptosis. Additionally, the HET-CAM method led to the observation of a strong irritating effect associated with nicotine.

Improving Recovery of Irritant Hand Dermatitis in Healthcare Workers With Workplace Interventions During the COVID-19 Pandemic

Introduction:

Occupational hand dermatitis is common among healthcare workers, with increased incidence during the COVID-19 pandemic. Irritant contact dermatitis accounts for the majority of occupational hand dermatitis and is largely due to frequent contact with hand hygiene products. Long-term prognosis of occupational contact dermatitis is often very poor. This study aims to identify and implement suitable workplace interventions to aid in the recovery of occupational irritant hand dermatitis among healthcare workers during the COVID-19 pandemic.

Methods

A quality improvement (QI) project was performed in a tertiary hospital using the Plan-Do-Study-Act model. Healthcare workers seen at the Occupational Dermatology Clinic from March 2020 to May 2021 for the first time for likely occupational irritant dermatitis were targeted for the project. Four workplace interventions were implemented: (a) substitute current alcohol-based hand rub (ABHR) with a different, gentler ABHR, (b) alternate ABHR with gentle hand wash products, (c) temporary job modification with less clinical work (d) switch latex gloves to nitrile gloves. The improvement was assessed after 2 months of workplace intervention using a visual analogue scale, based on changes seen on photographs taken at the baseline and monthly review. The target improvement was set at 70% after 2 months of workplace interventions.

Results

A total of 21 participants were included in the QI project. All participants were found to have significant improvement in their hand condition. The estimated mean reduction of signs and symptoms was 80% in comparison to their baseline hand condition before intervention.

Conclusion

Workplace interventions such as substituting irritant hand hygiene products with gentler alternatives and temporary reduction in clinical duties may be useful in improving the recovery rate of irritant hand dermatitis among healthcare workers. Areas with high hand hygiene workload or high incidences of hand dermatitis may opt to implement systemic workplace changes.

Therapeutische Besonderheiten bei Erkrankungen der Mamillenhaut

Die Mamillenregion ist durch besondere anatomische Verhältnisse charakterisiert und lässt sich aus dermatologischer Perspektive in Brusthaut, Haut des Brustwarzenhofes (Areola) und Haut der Brustwarze (Papilla mammae) unterteilen. Im klinischen Zusammenhang sind die Brustwarzen häufig während der Stillzeit durch mechanische Beanspruchung, Milieuänderung mit Mazeration durch den Milchfluss sowie durch mikrobielle Erreger alteriert. Zudem besteht hier die Gefahr der Entwicklung einer Mastitis puerperalis. Außerhalb der Schwangerschaft und Stillzeit finden sich gelegentlich an der Mamillenhaut Ekzemerkrankungen, häufig bei atopischer Disposition (atopisches Mamillenekzem) oder als irritatives Kontaktekzem („joggers nipple“). Seltener werden allergische Kontaktekzeme auf Konservierungsstoffe von Topika oder Metallen (Piercings) beobachtet. Auch im Rahmen einer Skabiesinfestation wird eine Beteiligung der Mamillen, insbesondere bei Frauen, regelmäßig beobachtet. Von großer klinischer Bedeutung sind seltene, präinvasive Läsionen eines Mammakarzinoms oder der Morbus Paget der Mamille vom extramammären Typ. Durch die besonderen anatomischen Gegebenheiten ist es naheliegend, dass bei der Anwendung von Topika sich auch spezifische Penetrationsbedingungen ableiten. Experimentelle Untersuchungen an Humanhaut ex vivo legen nahe, dass in Abhängigkeit von der Molmasse und der Löslichkeit des Arzneistoffs sowie des eingesetzten Vehikelsystems eine deutliche Zunahme der kutanen Bioverfügbarkeit, insbesondere an der Brustwarze selbst durch den transpapillären Diffusionsweg, auftreten kann. Dies sollte insbesondere bei der topischen Anwendung von Arzneistoffen mit bekanntem dosisabhängigem Nebenwirkungspotenzial (z. B. Glukokortikoiden) beachtet werden. Allerdings fehlt dafür bisher eine klinische Evidenz.

Household use of green and homemade cleaning products, wipe application mode, and asthma among French adults from the CONSTANCES cohort

While exposure to irritant and sprayed cleaning products at home is known to have a harmful role in asthma, the potential health effect of other categories or forms has not been investigated. We studied the associations of household use of cleaning products, including green, homemade products, and disinfecting wipes, with asthma based on data from the large French population-based CONSTANCES cohort. Participants completed standardized questionnaires on respiratory health and household use of cleaning products. Cross-sectional associations of cleaning products with current asthma, adjusted for gender, age, smoking status, BMI, and educational level, were evaluated by logistic regressions. Analyses were conducted in 41 570 participants (mean age: 47 years, 56% women, weekly use of the six specific products/forms studied varied from 11% to 37%). Weekly use of irritants (OR = 1.23 [1.13-1.35]), scented (OR = 1.15 [1.06-1.26]), green (OR = 1.09 [1.00-1.20]), and homemade products (OR = 1.19 [1.06-1.34]), as well as sprays (OR = 1.18 [1.08-1.29]), disinfecting wipes (OR = 1.21 [1.09-1.34]) were significantly associated with asthma, with significant trends according to the frequency of use. When they were not co-used with irritants/sprays, associations were reduced and persisted only for disinfecting wipes. Weekly use of disinfecting wipes at home was associated with current asthma, but fewer risks were observed for the use of green and homemade products.

Enhanced Excito-Repellency of Binary Mixtures of Plant-Based Mosquito Repellents Against Culex quinquefasciatus Say (Diptera: Culicidae), a Night Biting Mosquito Species

Efficacies of essential oils (EOs) of Vetiveria zizanioides (L.) Nash. (Poales: Poaceae) (VZ EO), Cananga odorata (Lam) Hook. F. & Thomson (Magnoliales: Annonaceae) (CO EO), and crude extract (CE) of Andrographis paniculata (Burm.F.) Wall ex. Nees (Lamiales: Acanthaceae) (AP CE), against laboratory (lab) and field strains of Culex quinquefasciatus Say were investigated. Irritant and repellent activities of individual and binary mixtures of plant extracts were compared with N,N-diethyl-m-toluamide (DEET) using an excito-repellency system. The irritant activity (direct tarsal contact), the mean percent escape response of VZ EO (91.67%, 83.33%), and CO EO (80%, 88.33%) were not significantly different compared with DEET (88.33%, 95%) against lab and field strains, respectively. Similarly, irritant responses in combinations (1:1 and 1:2, v:v) of either VZ EO or CO EO with AP CE were not significantly different from DEET against both strains (P > 0.001). The repellent activity (no tarsal contact), the mean percent escape response of VZ EO (68.33%), CO EO (61.67%), and VZ EO+AP CE (1:1, v:v) (81.67%) against lab strain and CO EO (85%) against field strain were not significantly different from that of DEET (P > 0.001). Interestingly, the greatest contact irritancy of VZ EO+AP CE (1:1, v:v) (96.67%) (P = 0.0026) and a stronger repellency response of CO EO (85%) (P = 0.0055) produced significantly different patterns of escape response compared with DEET against both lab and field strains, respectively. The EOs of VZ EO and CO EO or their mixture with AP CE showed potential as plant-based active ingredients for mosquito repellents. In addition, the major chemical constituents of VZ EO were β-vetivone (6.4%), khusimol (2.96%), and α-vetivone (2.94%) by gas chromatograpy-mass spectrometry.

Moisture-Associated Skin Damage: Expanding Practice Based on the Newest ICD-10-CM Codes for Irritant Contact Dermatitis Associated With Digestive Secretions and Fecal or Urinary Effluent From an Abdominal Stoma or Enterocutaneous Fistula

Moisture-associated skin damage (MASD) occurs when skin is repeatedly exposed to various sources of bodily secretions or effluents, often leading to irritant contact dermatitis, characterized by inflammation with or without denudation of affected skin. In 2020, the Wound, Ostomy and Continence Nurses Society commissioned an initiative that led to the addition of multiple International Classification of Diseases, Tenth Revision, Clinical Modification codes (ICD-10-CM) for irritant contact dermatitis caused by various forms of MASD for use in the United States. In a recent issue of the Journal of Wound, Ostomy and Continence Nursing, a clinical practice alert identifying the various new codes was published that summarized each of the new codes and provided highlights of the descriptions for each of these codes. This is the second in a series of 2 follow-up articles providing a more detailed description of the MASD conditions to which the newest irritant contact dermatitis ICD-10-CM codes apply. Specifically, this article reviews the clinical manifestations and assessment, pathophysiology, epidemiology, prevention, and management of irritant contact dermatitis associated with digestive secretions from a stoma or fistula, and fecal or urinary effluent from an abdominal stoma or enterocutaneous fistula.

Molluscum and Tinea and Warts, Oh My!

The skin is the largest organ in the human body, and it acts as the barrier between the world and our bodies. As such, it is constantly being exposed to infections, irritants, and allergens. Approximately one-third of primary care visits involve at least one skin complaint. This may manifest as a rash, a lesion, pruritis, pigment changes, or textural abnormalities. Whatever the presentation, it is important to know the common causes of these skin abnormalities and the appropriate management. Just as important as management is the ability to set expectations for patients, as many common skin conditions can be difficult to treat and may take significant time to resolve. This article will highlight some of the most common skin lesions we see in pediatric patients. [Pediatr Ann. 2022;51(1):e2-e5.].

Effects of piperonyl butoxide synergism and cuticular thickening on the contact irritancy response of field Aedes aegypti (Diptera: Culicidae) to deltamethrin

BACKGROUND

Exploiting indoor-resting mosquitoes' innate behavioral responses to commonly used insecticide is crucial in vector control programs. Indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs) treated with pyrethroids have become widely used for controlling dengue fever vectors. The present study tested the effects of piperonyl butoxide (PBO) synergism and cuticular thickening on the contact irritancy response of field A. aegypti (Diptera: Culicidae) to deltamethrin in Taiwan and Thailand.

RESULTS

The escape response of field mosquitoes treated with PBO was significantly elicited, with an escape percentage increase between 2- and 10-fold. In addition, the escape time was significantly lower in PBO-pretreated mosquitoes compared with field mosquitoes treated with deltamethrin alone. PBO-pretreated mosquitoes from seven out of 11 field strains exhibited a knockdown percentage of 11.23-54.91%, significantly higher than that of mosquitoes in corresponding strains treated with deltamethrin only. The Annan, Zhongxi, Sanmin, and North strains exhibited weak knockdown responses (≤3.75%). The mortality of PBO-pretreated field mosquitoes increased 2- to 75-fold compared with those treated with deltamethrin alone (mortality: 0-6.70%). Furthermore, the effect of cuticular thickness on the escape response of field mosquitoes was significant, that is, the escape response marginally increased inversely to cuticular thickness. By contrast, cuticular thickness was not significantly associated with knockdown or mortality percentage.

CONCLUSION

Irritant behavior in mosquitoes was significantly elicited by PBO synergism. PBO incorporating deltamethrin IRS or LLINs may be effective for controlling dengue fever vectors. © 2021 Society of Chemical Industry.

Podoconiosis: A Possible Cause of Lymphedema in Micronesia

Podoconiosis is a type of tropical lymphedema sharing some clinical characteristics with lymphatic filariasis. Also referred to as endemic non-filarial elephantiasis, podoconiosis is a non-infectious disease from barefoot exposure to irritant red clay soil of volcanic origins. Podoconiosis is most common in Ethiopia and has also been reported in many other countries, but not in the Pacific Islands. Lymphatic filariasis is endemic in the Pacific Islands and was historically reported as elephantiasis in Micronesia. It was considered to have been eradicated in Guam and the Northern Mariana Islands following World War II. A small number of patients in Saipan exhibited characteristics of lymphatic filariasis but were seronegative for filariasis. Clinical examination of these patients matched podoconiosis much more closely than filariasis. Moreover, these patients reported a history of chronic barefoot exposure to irritant red clay soil and a prodrome characteristic of podoconiosis. While this study is limited to several cases, the results suggest that podoconiosis could be considered a cause of non-filarial lymphedema in Saipan and perhaps other islands in Micronesia. Preventive patient education is focused on discouraging barefoot exposure to red clay soils, particularly in those with a family history of lymphedema. Early recognition of the possibility of podoconiosis would allow appropriate treatment and prevent progression to later debilitating stages of the disease.

Contact Dermatitis in Children

Contact dermatitis (CD) is commonly encountered in the pediatric population. Allergic and irritant are the two forms of CD and both cause significant clinical problems in children, but they are often underrecognized. The skin lesions in CD may be polymorphic and closely mimic other common pediatric skin diseases. The diagnosis usually requires patch testing after obtaining a detailed history and performing a physical examination. Metals, fragrances, and certain preservatives are the most common causative agents in children. This article discusses the pathophysiology, diagnosis, and management of this common skin condition in the pediatric population. [Pediatr Ann. 2021(5):e198-e205.].

Standardization and Chemical Characterization of Intravenous Therapy in Adult Patients: A Step Further in Medication Safety

BACKGROUND

Intravenous drug administration is associated with potential complications, such as phlebitis. The physiochemical characteristics of the infusate play a very important role in some of these problems.

AIM

The aim of this study was to standardize the dilutions of intravenous drugs most commonly used in hospitalized adult patients and to characterize their pH, osmolarity and cytotoxic nature to better guide the selection of the most appropriate vascular access.

METHODS

The project was conducted in three phases: (i) standardization of intravenous therapy, which was conducted using a modified double-round Delphi method; (ii) characterization of the dilutions agreed on in the previous phase by means of determining the osmolarity and pH of each of the agreed concentrations, and recording the vesicant nature based on the information in literature; and (iii) algorithm proposal for selecting the most appropriate vascular access, taking into account the information gathered in the previous phases.

RESULTS

In total, 112 drugs were standardized and 307 different admixtures were assessed for pH, osmolarity and vesicant nature. Of these, 123 admixtures (40%), had osmolarity values >600 mOsm/L, pH < 4 or > 9, or were classified as vesicants. In these cases, selection of the most suitable route of infusion and vascular access device is crucial to minimize the risk of phlebitis-type complications.

CONCLUSIONS

Increasing safety of intravenous therapy should be a priority in the healthcare settings. Knowing the characteristics of drugs to assess the risk involved in their administration related to their physicochemical nature may be useful to guide decision making regarding the most appropriate vascular access and devices.