The opposite effect of tapinarof between IMQ and IL-23 induced psoriasis mouse models

Tapinarof is an aryl hydrocarbon receptor (AHR) ligand which is used to treat plaque psoriasis in adults. However, the underlying mechanism is not yet fully understood. In this study, we applied two of the most studied psoriasis mouse models: topical application of imiquimod (IMQ) and subcutaneous injection of IL-23. Although both models successfully induced psoriasis-like lesions in mice, tapinarof had a completely opposite effect on the two models. Tapinarof decreased the expression of multiple essential cytokines involved in the pathological IL-23/IL-17/IL-22 axis and ameliorated IMQ-induced psoriatic dermatitis, inhibiting keratinocyte proliferation and abnormal differentiation. However, in the IL-23-injection-model, tapinarof instead aggravated the disease. Here, tapinarof increased epidermal thickness and differentiated epidermal dysplasia in mice. Our data suggest that tapinarof may have different effects on varied types of psoriasis.

Heat shock protein 90 (HSP90) inhibitors in gastrointestinal cancer: where do we currently stand?-A systematic review

PURPOSE

Dysregulated expression of heat shock proteins (HSP) plays a fundamental role in tumor development and progression. Consequently, HSP90 may be an effective tumor target in oncology, including the treatment of gastrointestinal cancers.

METHODS

We carried out a systematic review of data extracted from clinicaltrials.gov and pubmed.gov, which included all studies available until January 1st, 2022. The published data was evaluated using primary and secondary endpoints, particularly with focus on overall survival, progression-free survival, and rate of stable disease.

RESULTS

Twenty trials used HSP90 inhibitors in GI cancers, ranging from phase I to III clinical trials. Most studies assessed HSP90 inhibitors as a second line treatment. Seventeen of the 20 studies were performed prior to 2015 and only few studies have results pending. Several studies were terminated prematurely, due to insufficient efficacy or toxicity. Thus far, the data suggests that HSP90 inhibitor NVP-AUY922 might improve outcome for colorectal cancer and gastrointestinal stromal tumors.

CONCLUSION

It currently remains unclear which subgroup of patients might benefit from HSP90 inhibitors and at what time point these inhibitors may be beneficial. There are only few new or ongoing studies initiated during the last decade.

Phase 3 Trials of Tapinarof Cream for Plaque Psoriasis

BACKGROUND

Tapinarof cream is a topical aryl hydrocarbon receptor-modulating agent under investigation for the treatment of psoriasis. Tapinarof modulates the expression of interleukin-17 and the skin-barrier proteins filaggrin and loricrin.

METHODS

We conducted two identical phase 3 randomized trials of tapinarof in patients with mild-to-severe plaque psoriasis. Adults with a baseline Physician's Global Assessment (PGA) score of 2 (mild) to 4 (severe) (on a scale from 0 to 4, with higher scores indicating more severe psoriasis) and a percent of total body-surface area affected of 3 to 20% were randomly assigned in a 2:1 ratio to use tapinarof 1% cream or vehicle cream once daily for 12 weeks. The primary end point, PGA response, was a PGA score of 0 (clear) or 1 (almost clear) and a decrease from baseline of at least 2 points at week 12. Secondary efficacy end points at week 12 were a reduction of at least 75% in the Psoriasis Area and Severity Index (PASI) score, a PGA score of 0 or 1, the mean change from baseline in the percent of body-surface area affected, and a reduction of at least 90% in the PASI score. Patient-reported outcomes were the mean changes from baseline to week 12 in the proportion of patients who had a decrease of at least 4 points in the Peak Pruritus Numeric Rating Scale (PP-NRS) score (range, 0 [no itch] to 10 [worst imaginable itch]), the PP-NRS total score, the Dermatology Life Quality Index total score, and the Psoriasis Symptom Diary score.

RESULTS

In trials 1 and 2, a total of 692 and 674 patients, respectively, were screened, with 510 and 515 patients being enrolled. A PGA response occurred in 35.4% of the patients in the tapinarof group and in 6.0% of those in the vehicle group in trial 1 and in 40.2% and 6.3%, respectively, in trial 2 (P<0.001 for both comparisons). Results for secondary end points and patient-reported outcomes were generally in the same direction as those for the primary end point. Adverse events with tapinarof cream included folliculitis, nasopharyngitis, contact dermatitis, headache, upper respiratory tract infection, and pruritus.

CONCLUSIONS

Tapinarof 1% cream once daily was superior to vehicle control in reducing the severity of plaque psoriasis over a period of 12 weeks but was associated with local adverse events and headache. Larger and longer trials are needed to evaluate the efficacy and safety of tapinarof cream as compared with existing treatments for psoriasis. (Funded by Dermavant Sciences; PSOARING 1 and 2 ClinicalTrials.gov numbers, NCT03956355 and NCT03983980, respectively.).

Read-across can increase confidence in the Next Generation Risk Assessment for skin sensitisation: A case study with resorcinol

Historically skin sensitisation risk assessment for cosmetic ingredients was based on animal models, however regulatory demands have led to Next Generation Risk Assessment (NGRA), using data from New Approach Methodologies (NAM) and Defined Approaches (DA). This case study was meant to investigate if the use of resorcinol at 0.2% in a face cream was safe and a maximum use concentration could be defined. The NAM data and DA predictions could not provide sufficient confidence to determine a point of departure (POD). Therefore, the application of read-across was explored to increase the level of confidence. Analogue searches in various tools and databases using "mode of action" and "chemical structural features" retrieved 535 analogues. After refinement by excluding analogues without a defined structure, similar reactivity profile and skin sensitisation data, 39 analogues remained. A final selection was made based on three approaches: expert judgment, chemical similarity or Local Lymph Node Assay data (LLNA). All read-across approaches supported a moderate potency. A POD derived from the LLNA EC3 of 3.6% was determined leading to a favourable NGRA conclusion and a maximum use concentration of 0.36%. This was supported by a traditional risk assessment based on the available animal data for resorcinol.

Residents' Self-Reported Health Effects and Annoyance in Relation to Air Pollution Exposure in an Industrial Area in Eastern-Estonia

Eastern Estonia has large oil shale mines and industrial facilities mainly focused on electricity generation from oil shale and shale oil extraction, which produce high air pollution emissions. The "Study of the health impact of the oil shale sector-SOHOS" was aimed at identifying the impacts on residents' health and annoyance due to the industrial processing. First, a population-wide survey about health effects and annoyance was carried out. Second, the total and oil shale sectors' emitted concentrations of benzene, phenol, and PM2.5 were modelled. Third, the differences between groups were tested and relationships between health effects and environmental pollution studied using multiple regression analysis. Compared to the control groups from non-industrial areas in Tartu or Lääne-Viru, residents of Ida-Viru more frequently (p < 0.05) reported wheezing, chest tightness, shortness of breath, asthma attacks, a long-term cough, hypertension, heart diseases, myocardial infarction, stroke, and diabetes. All health effects except asthma were reported more frequently among non-Estonians. People living in regions with higher levels of PM2.5, had significantly higher odds (p < 0.05) of experiencing chest tightness (OR = 1.13, 95% CI 1.02-1.26), shortness of breath (1.16, 1.03-1.31) or an asthma attack (1.22, 1.04-1.42) during the previous year. People living in regions with higher levels of benzene had higher odds of experiencing myocardial infarction (1.98, 1.11-3.53) and with higher levels of phenol chest tightness (1.44, 1.03-2.00), long-term cough (1.48, 1.06-2.07) and myocardial infarction (2.17, 1.23-3.83). The prevalence of adverse health effects was also higher among those who had been working in the oil shale sector. Next to direct health effects, up to a quarter of the residents of Ida-Viru County were highly annoyed about air pollution. Perceived health risk from air pollution increased the odds of being annoyed. Annoyed people in Ida-Viru had significantly higher odds of experiencing respiratory symptoms during the last 12 months, e.g., wheezing (2.30, 1.31-4.04), chest tightness (2.88, 1.91-4.33 or attack of coughing (1.99, 1.34-2.95).

Systemic Pharmacokinetics, Safety, and Preliminary Efficacy of Topical AhR Agonist Tapinarof: Results of a Phase 1 Study

Tapinarof cream is a novel topical nonsteroidal agent that represents a unique class of anti-inflammatory molecules targeting the aryl hydrocarbon receptor. Study 201851 was an open-label, 2-cohort sequential study that assessed the systemic pharmacokinetics, safety, and efficacy of tapinarof in adults with moderate to severe atopic dermatitis. A total of 11 participants were enrolled: 5 received 2% cream, and 6 received 1% cream. Tapinarof was systemically absorbed, and measurable amounts were detected in both cohorts. Generally, plasma exposure was greater with the 2% cream and decreased from day 1 to day 21. Median T_max ranged from 1 to 4 hours. Preliminary efficacy results were similar between the 1% and 2% concentrations, with the 1% cream showing better tolerability based on 3 subjects in the 2% cohort who discontinued treatment because of systemic AEs. The efficacy and safety of 1% tapinarof support results of previous positive studies that used a different formulation. However, conclusions in the present study are limited because of the open-label design and small number of participants. The 1% cream was selected as the concentration for use in future studies because of its lower AE incidence and efficacy comparable to the 2% cream.

Antiseptic mouthwashes could worsen xerostomia in patients taking polypharmacy

OBJECTIVE

Polypharmacy is a common cause of xerostomia. This study aimed to investigate whether xerostomia could be an adverse drug event of mouthwashes, when they are used for longer than 2 weeks by patients taking polypharmacy.

MATERIALS AND METHODS

This cross-sectional observational study included 120 hospitalized patients (60 middle-aged and 60 elderly patients), taking polypharmacy (≥4 drugs daily) and at risk of drug-induced xerostomia. Xerostomia was assessed by questioning participants.

RESULTS

A total of 62.5% of patients complained of xerostomia. In the middle-aged group (mean age=44.0 (8.7) years; 35.0% women) xerostomia seemed independently associated to mouthwashes, at the limit of significance (OR=5.00, 95% CI=0.99-25.3, p=0.052). Active principles in mouthwashes were mainly quaternary ammonium compounds (91.9%). Mouthwashes may disturb the healthy balance of the biofilm moisturizing the oral mucosa. The biofilm contains mucins, salivary glycoproteins with oligosaccharides side chains able to sequester water and endogenous bacteria surrounded by a glycocalyx. Oral bacteria are fully susceptible to quaternary ammonium (chlorhexidine, hexetidine, cetylpyridinium chloride) and to other antiseptics used in mouthwashes, such as betain, resorcin, triclosan, essential oils and alcohol. However, caregivers currently recommend such dental plaque control products to patients suffering from xerostomia in order to reduce the risk of caries and periodontitis.

CONCLUSION

This study is the first report that use of antiseptic mouthwashes for more than 2 weeks could worsen xerostomia in patients taking polypharmacy. Oral care protocols should avoid this iatrogenic practice, particularly when xerostomia alters the quality-of-life and worsens malnutrition.

Classification of benzoyl peroxide as safe and effective and revision of labeling to drug facts format; topical acne drug products for over-the-counter human use; final rule

We, the Food and Drug Administration (FDA), are issuing this final rule to include benzoyl peroxide as a generally recognized as safe and effective (GRASE) active ingredient in over-the-counter (OTC) topical acne drug products. In addition, this final rule includes new warnings and directions required for OTC acne drug products containing benzoyl peroxide. We are also revising labeling for OTC topical acne drug products containing resorcinol, resorcinol monoacetate, salicylic acid and/or sulfur to meet OTC drug labeling content and format requirements in a certain FDA regulation. This final rule is part of our ongoing review of OTC drug products and represents our conclusions on benzoyl peroxide in OTC acne drug products.

Aortic root reimplantation using a Valsalva graft for postoperative pseudoaneurysm after acute aortic dissection

We report a reoperative case in which a Valsalva graft was utilized on a 64-year-old woman who had previously undergone emergency repair of a DeBakey type I acute aortic dissection. On follow-up computed tomography (CT), she was found to have pseudoaneurysms of both proximal and distal anastomoses. We performed valve-sparing aortic root replacement (VSRR) with the reimplantation technique and total arch replacement, since we felt that a graft with pseudosinuses helps to prevent torsion of the coronary arteries. The postoperative course was uneventful, and postoperative echocardiography revealed no significant aortic valve regurgitation. The pathology results raised the hypothesis that pseudoaneurysm formation might have been related to the use of gelatin-resorcinol-formaldehyde (GRF) glue at the time of the initial intervention.

[Proximal anastomotic pseudoaneurysm due to gelatin-resorcin-formalin (GRF) glue after replacement of ascending aorta for acute aortic dissection; report of a case]

A 78-year-old man had previously undergone replacement of ascending aorta using gelatin-resorcin-formalin (GRF) glue for acute aortic dissection. Five years later, a follow-up computed tomography (CT) showed an aortic root pseudoaneurysm. Ultrasound cardiography revealed moderate aortic regurgitation and pseudoaneurysm of aortic root. Aortic root replacement was planned based on a clinical diagnosis of an anastomotic pseudoaneurysm of the aortic root. The patient was discharged without complication 26 days after surgery. In the histopathological examination, the necrotic change of smooth muscle cells in the aortic media was revealed. Previous reports suggests that the use of GRF glue for reconstructing the dissected aorta results in higher rates of postoperative redissection or pseudoaneurysm. Therefore, careful postoperative follow-up is necessary in such cases and further improvements in the quality of glue or alternative methods will be necessary to prevent problems in the first place.

Evaluation of gelatin/resorcinol/aldehyde as a hemostatic agent and tissue adhesive: an experimental study in rat

Use of gelatin/resorcinol/formaldehyde glue as a tissue adhesive and hemostatic agent was evaluated experimentally after modification of the aldehyde component. Gelatin/ resorcinol/aldehyde (GRA) glue was prepared by mixing gelatin and resorcinol and cross-linking with a blend of formaldehyde/glutaraldehyde. After wedge resection of the liver of 28 albino rats, bleeding was controlled, and the cut surfaces were joined with GRA. Liver biopsy was done at 7, 14, 21, and 28-day intervals. Hemostasis was excellent in 71.4%, satisfactory in 25.0%, and poor in 3.6%. Mean time for tissue adhesion was 2.6 minutes. No necrosis or bile leakage was seen. Visibility of site of repair decreased from 50.0% on day 7 to 14.3% on day 28. Residual glue was seen microscopically on day 28 in 43% cases. GRA is safe and good hemostatic, tissue adhesive, and sealant in rat liver.

A clinical assessment of a patch test kit marketed to U.K. hairdressers for detecting hair dye allergy

BACKGROUND

In 2004 a U.K.-based company developed and marketed a patch test kit (Colourstart); Trichocare, Ridgmont, Beds, U.K.) for use by hairdressers. It is intended to assess whether clients have a 'problem with hair dye' and promotes itself as the 'only practical solution to sensitivity testing'. However, a patient presented with a hair dye reaction that had not been detected while using this patch test system.

OBJECTIVES

To assess the Colourstart system in the next seven consecutive patients presenting with a history of adverse reactions to hair dyes.

METHODS

The Colourstart system was tested in parallel with commercially available hair dye patch test reagents, where applicable.

RESULTS

Only three of seven patients allergic to p-phenylenediamine were detected using this system and one patient allergic to toluene-2,5-diamine sulphate was not detected using this system.

CONCLUSIONS

The results raise concerns about the sensitivity of this kit for consumer protection, but also wider questions about the regulation, use and interpretation of 'home diagnostic patch test kits' in general.

Late Complications of Gelatin-Resorcin-Formalin Glue in the Repair of Acute Type A Aortic Dissection

BACKGROUND

During surgical treatment for acute type A aortic dissection, gelatin-resorcin-formalin glue is generally applied and its efficacy has been reported. However, some late complications that are potentially associated with this glue have also been reported. In the present study, we reviewed our experiences of treatment for acute type A aortic dissection and late complications that occurred in the anastomotic site, which needed a reoperation.

METHODS

From October 1994 to August 2005, 68 patients underwent emergency surgery for acute type A aortic dissection. Gelatin-resorcin-formalin glue was applied to 56 (82.4%) of these patients at one or both of the distal and proximal anastomosis sites.

RESULTS

Eight (11.8%) patients died in hospital within 30 days after the operation, among which two patients already had cerebral complications prior to the surgery. There were five late deaths from causes unrelated to cardiac events. Five patients developed an aortic pseudoaneurysm at the anastomotic site and underwent a late reoperation. All of these patients had been treated with gelatin-resorcin-formalin glue during the previous operation. Histologic examination of the resected aortic wall after the reoperation revealed tissue necrosis, severe local inflammation, and organization of old thrombi at the site of the glue application.

CONCLUSIONS

Late complications after the use of gelatin-resorcin-formalin glue may occur with a certain amount of risk, suggesting its toxicity for aortic tissue. Therefore, proper use of this glue and close follow-up of the patients are strictly required.

Ostial stenosis after Bentall technique using glue: percutaneous stenting may be ineffective

BACKGROUND

Hemorrahage after coronary re-implantation during a Bentall surgery is a rare complication. In case of friable tissue, the use of a felt disc usually solves the problem. The use of resorcinol-formol-glue should be avoided to prevent tissue damage. Extrinsic compression of the coronary arteries has been reported with the use of this surgical glue.

CASE

We report a rare case of extrinsic compression of both coronary arteries after a Bentall procedure. A 50-year-old man with severe aortic valve stenosis, without coronary disease and an ascending aortic aneurysm, underwent a modified Bentall procedure with insertion of a valved tube and coronary re-implantation using surgical glue. Seven weeks later he suffered severe acute coronary ischemia and both coronary ostium were compressed by a dense and hard fibrose material. Three months after stenting, the patient required coronary surgery because of severe myocardial ischemia. Transesophageal and intracoronary ultrasounds were useful for the diagnosis of this rare complication.

CONCLUSIONS

Use of glue should be avoided for coronary reimplantation during Bentall surgery. In cases of external ostial compression by glue reaction, stenting may be ineffective and surgical coronary revascularization may be needed.

[Durability of aortic root preservation using gelatin-resorcin-formalin glue in acute type A aortic dissection]

During the last 9 years, aortic root preservation using gelatin-resorcin-formalin (GRF) glue was performed in 63 patients as a part of surgery for acute type A aortic dissection. Residual aortic regurgitation (AR) was evaluated, grading 0 to IV+ by echocardiography. The survival and root reoperation-free rates were also assessed. The operative mortality was 9.5% (6 patients). Early postoperative AR < or = I+, = II+ and > or =III+ were 93, 7 and 0%, respectively. Late postoperative AR > or =III+ was observed in 4 patients. Root reoperation was performed in 4 patients (7.0%). In a case of reoperation, medial degeneration was found in the aortic wall, suggesting toxic effect of GRF glue. The actuarial survival and root reoperation-free rates at 9 years were 73 and 80%, respectively. In conclusion, aortic root preservation with the proper use of GRF glue has long-term durability with very low adverse effect.

The use of resorcine adhesive in repairing osteochondral's defect in knees of rabbits

PURPOSE

To study the morphology of the articulation of the knee of rabbits after the repairing of the defect osteochondral standardized with resorcina adhesive or metallic synthesis.

METHODS

The procedure was to the creation of the defect osteochondral in femoral medial condylus of the knee of 80 rabbits, The animals were distributed in two groups with continuations of 7 and 42 days and submitted to the technique G (resection and retreat of the fragment osteochondral of the femoral medial condylus and relocation with resorcina adhesive), technique S (resection and retreat of the fragment osteochondral of the femoral medial condylus and relocation and metallic synthesis) or technique C (resection and retreat of the fragment osteochondral of the femoral medial condylus, leaving the empty standard defect the control). It was Made clinical study, radiographic, macroscopic and histological in two groups.

RESULTS

the resorcina adhesive provokes: necrosis of the fragment osteochondral in 100% and 95%, degeneration 90% and 100%, free body in 80% and 65% respectively in the group I and II; compared with the metallic synthesis that it presented: necrosis in 25% and 35%, degeneration 25% and 35%, free body in 35% and 10% respectively in the group I and II.

CONCLUSION

the resorcinol adhesive, related with the necrosis, cartilaginous degeneration and detachment of the fragment osteochondral lives frequently that the metallic synthesis.

Devastating late complication for repair of type A acute aortic dissection with usage of gelatin-resorcinol-formalin glue

OBJECTIVES

We review cases of pseudoaneurysm formation of the graft anastomosis sites following repair of type A acute aortic dissection by our original leak-proof technique for dissected aortic wall reinforcement with xenopericardium and gelatin-resorcinol-formalin (GRF) glue.

CASES

A 47-year-old male presented inferior acute myocardial infarction with bradycardia and cardiogenic shock 34 months after the initial total arch replacement for acute aortic dissection. The patient underwent reoperation with total arch replacement and coronary artery bypass grafting to the right coronary artery. There was rupture of the proximal anastomosis with clotted pseudoaneurysm formation extending over the right ventricle. The right coronary artery was compressed by the pseudoaneurysm. The distal anastomosis also ruptured with localized pseudoaneurysm formation. Twenty-two patients with type A acute aortic dissection underwent aortic repair by our original leak-proof technique for dissected aortic wall reinforcement with xenopericardium and gelatin-resorcinol-formalin glue between 1997-2003. Four patients developed redissection of the anastomosis sites, which required reoperation, including the current case.

DISCUSSION

The cause of redissection was unclear, however, use of GRF glue itself might develop tissue damage and redissection of the aorta, and also glued xenopericardium strip reinforcement in our original technique might accelerate damage to the aortic wall.

CONCLUSION

Follow-up examination is mandatory for the patient of aortic repair with the use of GRF glue.

Aortic root necrosis after surgical treatment using gelatin-resorcinol-formaldehyde (GRF) glue in patients with acute type A aortic dissection

BACKGROUND

Although gelatin-resorcinol-formaldehyde (GRF) glue is used for surgical repair of acute type A aortic dissections, late complications possibly ascribed to toxic effects of GRF glue have been reported. We analyzed the benefits and risks of using GRF glue.

PATIENTS AND METHODS

Between January 1990 and August 2003, 269 consecutive patients underwent emergency operations for acute type A aortic dissection. GRF glue was not used in 47 patients (non-GRF group) who were operated on until May 1995 and was used in the 222 (GRF group) who underwent operation subsequently.

RESULTS

The rate of in-hospital mortality was significantly higher in the non-GRF group (31.9%) than in the GRF group (12.6%) (p<0.0001). In the GRF group, false aneurysms were found in 31 patients (31/194 survivors, 16.0%) 1-65 (mean, 30+/-18) months after initial operation. Reoperation was done in 24 of these patients. At reoperation, the site to which GRF glue was applied had degenerated, and the anastomosis between the aortic root and prosthesis had opened widely, creating a false aneurysm and resulting in aortic regurgitation with prolapse of the coronary cusps. The mortality rate of reoperation was 4.2% (1/24).

CONCLUSION

The use of GRF glue improved the short-term outcome of surgery for acute type A aortic dissection, but was associated with a high incidence of false aneurysms forming at the site of proximal anastomosis, where GRF glue had been applied. Patients in whom GRF glue has been used should be carefully followed up after surgery.

Late Complications Following Surgery for Type A Acute Aortic Dissection Using Gelatin-Resorcin-Formaldehyde Glue: Report of Two Cases

Gelatin-resorcin-formaldehyde (GRF) glue has been widely applied during operations for acute aortic dissection (AAD). At our institution, GRF glue was applied in 40 patients who underwent surgical procedures for AAD from 1995, two of whom needed a reoperation because of the development of a redissection and/or a pseudoaneurysm at the anastomotic sites. The operative findings and histological examinations suggested that the application of GRF glue during the initial operations might be related to the development of a redissection and/or a pseudoaneurysm.

Tissue Adhesives for a Sutureless Fadenoperation: An Experimental Study in a Rabbit Model

PURPOSE

To use tissue adhesives for a sutureless Fadenoperation to eliminate perioperative risks related to the sutures.

METHODS

In an in vivo procedure, 120 superior recti muscles in New Zealand White rabbits were subjected to the posterior fixation procedure, at a distance of 6 mm from the insertion point of the muscle. They were divided into four groups of 30 muscles, according to the material used to perform a myopexy: group 1 (control): nonabsorbable 5-0 polyester sutures; group 2: n-butyl-2-cyanoacrylate adhesive; group 3: fibrin glue; group 4: gelatin-resorcin-formaldehyde-glutaraldehyde (GRFG) adhesive. The animals were examined at 1, 7, 14, and 21 days after surgery. Afterward, they were killed, and their eyes were enucleated to measure the distance between the myopexy and the anatomic insertion point and to assure the strength of the bond with a dynamometer. Finally, a histologic examination was performed.

RESULTS

Almost all eyes were clear after the third week, although group 4 presented the most intense inflammatory reaction. In histologic examination, groups 1 and 2 showed a chronic inflammatory reaction of the foreign-body type, with similar intensity. Fibrin glue induced minimal inflammation, but GRFG adhesive produced a pronounced reaction. Concerning the distance of the myopexy, groups 1 and 2 presented measures close to the expected distance of 6 mm, whereas groups 3 and 4 showed a greater variability. All groups performed well in the strength test, with no statistically significant differences among them.

CONCLUSIONS

n-Butyl-2-cyanoacrylate adhesive performed best in the sutureless Fadenoperation, characterized by precision in the expected distance of myopexy, sufficient resistance to separation, and acceptable inflammatory reaction.

A study of cross-reactions between mango contact allergens and urushiol

The allergens causing mango dermatitis have long been suspected to be alk(en)yl catechols and/or alk(en)yl resorcinols on the basis of observed cross-sensitivity reactions to mango in patients known to be sensitive to poison ivy and oak (Toxicodendron spp.). Earlier, we reported the 3 resorcinol derivatives: heptadecadienylresorcinol (I), heptadecenylresorcinol (II) and pentadecylresorcinol (III); collectively named 'mangol', as mango allergens. In this study, we extracted the 1st 2 components (I and II) from the Philippine mango, adjusted them to 0.05% concentration in petrolatum and patch tested the components on 2 subjects with mango dermatitis. Both subjects reacted to I. 1 subject also elicited a weaker positive reaction to II. To investigate the cross-reaction between mangol and urushiol, we also patch tested the same subjects with urushiol. The subject sensitive to II reacted to urushiol. 6 subjects with a history of lacquer contact dermatitis and positive reactions to urushiol were similarly patch tested. 5 persons reacted to I. 2 subjects also exhibited a slower but positive reaction to II. This is the 1st report in which heptadec(adi)enyl resorcinols known to be present in mango have been shown to elicit positive patch test reactions in mango-sensitive patients.

Resorcinol-formaldehyde resin "Russian Red" endodontic therapy

Resorcinol-formaldehyde resin is a material used in endodontic therapy in many foreign countries. With immigration to the United States increasing, American dentists need to become familiar with resorcinol-formaldehyde therapy. It contains two potentially toxic components, formaldehyde (liquid) and resorcinol (powder). Zinc oxide or barium sulfate may be used for radiopacity. When 10% sodium hydroxide is added to the mixture, polymerization occurs, which can form a brick-hard red material that has no known solvent. Several variations in technique exist. The catalyst can be mixed in before insertion into the tooth, added after the mixture is inserted, or not used. Providers believe pulp tissue will be fixed and bacteria destroyed apical to the level of resorcinol-formaldehyde resin placement. Canals are frequently not instrumented or obturated to their full length. Few success-failure studies have been published and results are contradictory. Consequently, providers have little guidance regarding when to retreat or for predicting the difficulty of retreatment.

Toxicology review and risk assessment of resorcinol: thyroid effects

Resorcinol administered at high doses to rodents can disrupt thyroid hormone synthesis and can produce goitrogenic effects. These effects were not seen in a 2-year bioassay at doses of up to 520 mg/kg/day. There are species-specific differences in synthesis, binding, and transport of thyroid hormone that complicate interpretation of goitrogenesis in rodents. Clinical case reports from patients undergoing resorcinol therapy for dermatological indications reveal thyroid side effects when copious amounts of resorcinol-containing ointments are applied to integrity-compromised skin for months to years. Effect levels were greater than 34 mg/kg/day. Occupational epidemiology studies provide no evidence that exposure to resorcinol at levels greater than found in the general environment causes thyroid dysfunction. Studies investigating the relationship between endemic goiter and exposure to "phenolics," including resorcinol, in drinking water do not fulfill accepted scientific criteria for establishing resorcinol as a cause of thyroid disease. Those reports neither quantify exposure levels nor demonstrate dose-response relationships or rule out confounding by the multiple other chemicals present in water supplies, by bacterial contamination of water, or by nutritional factors. A risk assessment comparing potential worst-case exposures to resorcinol through its use in dermatological preparations supports the conclusion that under real-world conditions, human exposures to resorcinol are not expected to cause adverse effects on thyroid function.

A simple trick for repairing coronary pseudoaneurysm complicating a Bentall operation

Coronary pseudoaneurysms are a known complication of the Bentall wrap-inclusion method of composite valve grafting. We describe two cases to illustrate a straightforward technique for repair and prevention of coronary pseudoaneurysm formation.

Late aortic root redissection following surgical treatment for acute type A aortic dissection using Gelatin-Resorcin-Formalin glue

OBJECTIVES

Although Gelatin-Resorcin-Formalin (GRF) glue is widely used in surgery for acute aortic dissection, late complications possibly due to the glue, such as late aortic root redissection, have also been reported. We have experienced similar complications, some of which required redo surgeries, and these cases are reviewed.

METHODS

Twenty-six consecutive patients who underwent surgery for acute type A aortic dissection using GRF glue, from December 1996 to February 2001, were retrospectively studied, with a special focus on any late complications and any reoperation.

RESULTS

Of the 21 patients who survived and were followed as outpatients, false aneurysms were found in 5 patients (21%) at 24-42 (mean 34) months following the initial surgery. Of these, 2 patients required resternotomy because of the increasing aneurysm diameter. In both cases, the aortic root was redissected at the site of the GRF glue use where the anastomosis between the aortic root and the prosthesis had widely opened and had become the aneurysm entry point. Significant aortic regurgitation was noticed in 3 patients (14%, 1 of whom showed a false aneurysm), and 2 of these underwent reoperation for aortic root redissection.

CONCLUSIONS

A high incidence of aortic root redissection with false aneurysm and/or aortic insufficiency was found following the surgery for acute aortic dissection using GRF glue. These patients should be carefully followed for years after surgery.

Aortic wall alterations after use of gelatin-resorcinol-formalin glue

We report the case of a patient who underwent reoperation 8 years after aortic valve replacement because of aneurysmal dilatation of the aortic root. During the initial intervention, gelatin-resorcinol-formalin glue had been applied on the outside of the aortic root. Perioperative examination revealed a necrotic appearance of the right coronary sinus, with contained ruptures at two different sites. Histologic analysis showed major destruction of the aortic root media, leading to vascular wall thinning and rupture. The use of gelatin-resorcinolformalin glue may expose patients to major alterations of the aortic wall.

Exogenous ochronosis. An update on clinical features, causative agents and treatment options

Exogenous ochronosis is clinically and histologically similar to its endogenous counterpart; however, it exhibits no systemic effects and is not an inherited disorder. It is characterized by an asymptomatic hyperpigmentation of the face, sides and back of the neck, back, and extensor surfaces of the extremities. The associated ochronotic discoloration most commonly results from use of products containing hydroquinone. It also occurs following use of antimalarials and products containing resorcinol, phenol, mercury or picric acid. The etiology of hydroquinone-induced hyperpigmentation in exogenous ochronosis remains speculative. The majority of patients with this condition are Black, but it has been reported to occur in Hispanics and Caucasians. Exogenous ochronosis is prevalent among South African Blacks, but is believed relatively uncommon within the US. The reasons for this phenomenon are not clear, but it could be a result of the use of skin care products containing resorcinol in combination with hydroquinone or the use of hydroquinone in a hydroalcoholic lotion. Treatment of this condition is difficult. The offending agent must be avoided, but improvement occurs only slowly. A number of topical agents have been studied as have dermabrasion and the use of lasers. Controlled studies in larger numbers of patients are require to determine the true efficacy of newer treatments.

Ostial stenosis of coronary arteries after complete replacement of aortic root using gelatin-resorcinol-formaldehyde glue

Coronary ostial stenosis between an interposition graft and coronary artery is rare and fatal. A 46-year-old woman who had reconstruction of both coronary arteries using interposition grafts for type A acute dissecting aneurysm presented with acute chest pain. Emergent coronary artery bypass grafting was done with saphenous vein grafts. Inappropriate use of gelatin-resorcinol-formaldehyde glue can be associated with ostial stenosis in the long term. Transesophageal echocardiography is useful to diagnose ostial stenosis of the coronary arteries.

Role of biologic glue repair of proximal aortic dissection in the development of early and midterm redissection of the aortic root

BACKGROUND

Redissection of the aortic root after supracommissural aortic graft replacement with reapproximation of the layers of the dissected aortic root is relatively rare. Causes and surgical treatment of this lesion remain controversial.

METHODS

From January 1983 to September 2000, 130 patients had emergency operation for acute type A aortic dissection. Of them, 57 patients underwent root reconstruction using biologic glues and 4 patients (7.0%) developed redissection of the aortic root associated with moderate to severe aortic regurgitation 5 to 27 months after the initial operation. In all patients, the proximal false lumen was obliterated with infusion of gelatin-resorcinol-formaldehyde (GRF) glue or BioGlue and the aorta was reinforced with Teflon felt strip or Surgicel placed on its outside wall.

RESULTS

During reoperation, the noncoronary aortic sinus was found to be redissected in all patients with the dissection extending retrogradely to the aortic annulus. This resulted in aortic regurgitation with prolapse of the noncoronary cusp because the proximal suture line dehisced. Histopathology showed disappearance of the nuclei of the medial smooth muscle cells, suggesting tissue necrosis at the site of GRF glue application. The lesions were treated successfully with full root replacement using a freestyle heterograft bioprosthesis or a composite graft prosthesis.

CONCLUSIONS

The use of biologic glues for reapproximating the layers of the dissected aortic root is associated with a certain amount of risk of aortic wall necrosis. Therefore, care should be taken to ensure proper use of these glues. Full root replacement could be a preferable technique for treating redissection of the aortic root.

Contact allergy to balsam of Peru. II. Patch test results in 102 patients with selected balsam of Peru constituents

BACKGROUND

In Switzerland, Germany, and Austria, allergic reactions to balsam of Peru (BP) have now made it the third most common contact allergen.

OBJECTIVE

A series of 20 single BP constituents (including resorcinol monobenzoate), established in 1995, was used for patch tests in patients with a positive reaction to BP in the standard series.

MATERIALS AND METHODS

Between 1995 and 1998, 2,273 patients were tested with the standard series, including BP, fragrance mix (FM), and propolis. Patients positive for BP were requested to participate in a further test using the 19 compounds of the BP constituents and resorcin monobenzoate (BP series); 102 patients agreed and were patch tested. The results of the 72-hour reading were used for the evaluation.

RESULTS

A total of 93 patients reacted to 1 or more of the BP series compounds. Positive reactions were seen, in decreasing order, to cinnamic alcohol, cinnamic acid, coniferyl benzoate, benzoic acid, cinnamyl cinnamate, eugenol, resorcinol monobenzoate, coniferyl alcohol, and benzyl alcohol. There were no positive reactions to vanillin or ferulic acid. A correlation between skin lesions and frequent consumption of sweets was found in 7 patients with major positive test reactions to coniferyl benzoate and benzyl alcohol. Most of the reactions to eugenol and isoeugenol had less to do with BP itself than with a primary sensitization to fragrances. Although resorcin monobenzoate (RMB) has up to now not been detected in BP, 16 patients reacted distinctly to this compound. Eleven were strong smokers; the remaining ones had contact with plastic materials that have been reported to contain RMB. RMB is used frequently as an antioxidant in synthetic material. When these patients stopped smoking, the skin lesions cleared. However, consumption of sweets caused recurrences.

CONCLUSION

The evaluation of reactions to single constituents of BP by testing with the special BP series facilitates understanding how sensitization may be acquired. The allergen may prove to be BP itself or 1 or more of its constituents. Testing for the constituents of this series may provide patients with a more specific allergen diagnosis and may facilitate improved therapy. BP may function as an important indicator for contact allergy to RMB.

Diagnosis by intraoperative transesophageal echocardiography of acute thrombosis of mechanical aortic valve prosthesis associated with the use of biological glue

Mechanical aortic valve thrombosis is an uncommon complication of valve replacement. Inadequate anticoagulation is observed in 45% of patients presenting with this complication and it occurs as close as 15 days postoperation (1). Failure to wean from cardiopulmonary bypass (CPB) after aortic valve replacement may be because of a multitude of pathologies. We present a case where easy access to transesophageal echocardiography (TEE) allowed a rapid diagnosis of acute mechanical aortic valve occlusion with subsequent successful surgical management.

[Sensitization to resorcinol in a prescription verrucide preparation: unusual systemic clinical features and prevalence]

BACKGROUND

Resorcinol is a rare sensitizer. In Lorraine, where it is used in high concentrations in an anti-wart ointment, this molecule has induced many cases of allergy. The purpose of this study was to describe clinical features in patients sensitized to resorcinol, to determine the incidence of sensitization in Lorraine and ascertain the occurrence of cross reactions with other phenolic pro-haptens.

PATIENTS AND METHODS

The files of all patients sensitized to resorcinol were studied from 1992 to 1999. Over a 20-month period, 983 consecutive patients underwent our standard patch tests where we included resorcinol (1 p. 100 in petrolatum). Co-sensitization with other pro-haptens was studied in all sensitized patients.

RESULTS

Sensitization to resorcinol was observed in 0.5 p. 100 of the 983 consecutively tested patients. Contact sensitization was found in 24 patients, who all but one had previously used the anti-wart ointment containing resorcinol. All developed contact eczema on the site of application of the ointment, with generalized urticaria (4 cases), pompholyx (1 case), and generalized papulo-vesicular rash with pompholyx (6 cases). Positive patch tests were observed with resorcinol monobenzoate (15/19 cases), pyrocatechol (7/14 cases), pyrogallol (9/19 cases), salicylaldehyde (2/17 cases), and hydroquinone (6/17 cases). Negative patch tests were observed with phenysalicylate, hexylresorcinol, or fluoresceine.

CONCLUSION

Resorcinol should not be applied in high concentrations as it can provoke generalized sensitization and co-sensitization with other pro-haptens.

Patch test sensitization to Compositae mix, sesquiterpene-lactone mix, Compositae extracts, laurel leaf, Chlorophorin, Mansonone A, and dimethoxydalbergione

BACKGROUND

Compositae mix and sesquiterpene-lactone (SL) mix are important patch test substances to show allergic contact dermatitis from various Compositae plants.

OBJECTIVES

The aims of this study are to calculate the sensitization rates to Compositae mix and SL mix in an occupational dermatology clinic and to describe cases of active sensitization caused by patch testing with Compositae mix and SL mix.

METHODS

Conventional patch testing was performed. SL mix (0.1%) and Compositae mix (6% in petrolatum) were tested in a modified European standard series and a plant allergen series. Testing with other appropriate patch test series was also performed.

RESULTS

SL mix provoked 8 allergic patch test reactions (0.7%) in 1,076 patients, whereas Compositae mix was positive in 15 of 346 patients (4.2%). Three patients were actively sensitized to Compositae mix and 1 patient to SL mix. One patient was also sensitized to other plant allergens in a series of allergenic plant chemicals, namely to Mansonone A, an ortho-quinone; (R)-3,4-dimethoxydalbergione, a quinone; and Chlorophorin, a hydroxy stilbene. Allergic patch test reactions to laurel leaf were caused by cross-sensitization to SLs.

CONCLUSION

Compositae mix seems to be a more important patch test substance than SL mix to detect allergic contact dermatitis to Compositae plants, but patch testing may sensitize. The concentration of the individual components of the Compositae mix should be adjusted so that the mix detects allergic patients but does not sensitize.

Contact allergy to resorcinol monobenzoate

Resorcinol monobenzoate is an ultraviolet light absorber used in cellulose plastics and is known to cause allergic contact dermatitis reactions. It is the most important allergen in spectacle frames but can be a potential allergen in shoes as well. We report 7 cases of allergy to resorcinol monobenzoate with different clinical presentations. Our series further illustrates several possible cross-sensitizers.

Anaphylactic shock during endodontic treatment due to allergy to formaldehyde in a root canal sealant

A 41-yr-old patient experienced an anaphylactic shock reaction caused by formaldehyde in a root canal sealant during endodontic treatment. The clinical events, positive skin tests, and a high level of immunoglobin E to formalin RAST (class 4) suggest the involvement of immunoglobin E-dependent mechanisms toward formaldehyde. This very infrequent observation in endodontic therapy focuses attention on the different pathological manifestations related to formalin, their mechanisms, and the prevention possibilities in dentistry.

Anticonvulsant activity of two metabotropic glutamate group I antagonists selective for the mGlu5 receptor: 2-methyl-6-(phenylethynyl)-pyridine (MPEP), and (E)-6-methyl-2-styryl-pyridine (SIB 1893)

The selective mGlu5 antagonists, MPEP, 2-methyl-6-phenylethynyl-pyridine, and SIB1893, (E)-6-methyl-2-styryl-pyridine, have been evaluated as antiepileptic drugs in DBA/2 mice and lethargic mice. Clonic seizures induced by the selective mGlu5 agonist, (R,S)-2-chloro-5-hydroxyphenylglycine (CHPG), 3 micromol intracerebroventricularly (i.c.v.), are potently suppressed by both compounds (MPEP, ED(50)=0.42 [0.28-0.62] mg/kg intraperitoneally (i.p.); SIB 1893 ED(50)=0.19 [0.11-0.33] mg/kg i.p. ). Clonic seizures induced by the mGlu1,5 agonist, 3, 5-dihydroxyphenylglycine (DHPG), 1.5 micromol i.c.v., are less potently suppressed by both compounds (MPEP, ED(50)=22 [13-38] mg/kg i.p., 110 [67-180] nmol i.c.v.; SIB1893, ED(50)=31 [18-54] mg/kg i.p. , 95 [82-110] nmol i.c.v.). Sound-induced seizures in DBA/2 mice are suppressed at 15 min by MPEP and SIB 1893 (MPEP ED(50) clonic seizures=18 [10-32] mg/kg i.p., 93 [69-125] nmol i.c.v.; tonic seizures=6.1 [4.5-8.3] mg/kg i.p., 46 [26-80] nmol i.c.v.; SIB 1893 ED(50) clonic seizures=27 [17-44] mg/kg i.p., 825 [615-1108] nmol i. c.v., tonic seizures=5.4 [3.4-8.6] mg/kg i.p., 194 [113-332] nmol i. c.v.). The ED(50) for MPEP for impaired rotarod performance is 128 [83-193] mg/kg i.p., at 15 min, i.e. a therapeutic index for sound-induced seizures of 5-20. In lethargic mice (lh/lh), a genetic absence model, MPEP, 50 mg/kg i.p., caused a marked reduction in the incidence of spontaneous spike-and-wave discharges. These selective antagonists of mGlu5 block seizures due to activation of mGlu5 at very low systemic doses. At rather higher doses they block convulsive and non-convulsive primary generalised seizures.

Late complications of tissue glues in aortic surgery

BACKGROUND

Tissue glues are used in cardiothoracic surgery as an adjunct to operative procedures where tissues are frail, as in aortic dissection, or where added hemostasis is required. This study was undertaken to review the use of tissue glue in our institution over a 5.5-year period. The aim of the study was to identify any potentially glue-related complications.

METHODS

A review of tissue glue use for the period from January 1993 to September 1998 was performed and pre-, intra-, and postoperative parameters were collected. After some unusual surgical findings, of special interest was a range of pathology found at late reoperation.

RESULTS

A total of 67 cases of tissue glue use were identified, with the majority of operations for type A dissection (76%). There were two intraoperative deaths. Twenty-seven of 65 patients (41%) required 29 further open chest operations; of these, 17 were for acute problems of bleeding or tamponade. Twelve patients (18%) underwent late reoperations months to years later. Nine of these patients, concentrated in two operative groups (7 patients with aortic valve resuspension and 2 patients who had undergone "switch" operations for transposition of great vessels), displayed complications related to the application of gelatin-resorcinol-formaldehyde (GRF) tissue glue.

CONCLUSIONS

Indications for tissue glues in cardiothoracic surgery must be carefully considered. We have reviewed our use of some tissue glues in acute type A aortic dissections and in pediatric cardiac patients and have discontinued the use of GRF glues because of unsatisfactory long-term complications.

Contact dermatitis from polyvinyl chloride identification bands

One case of allergic contact dermatitis caused by polyvinyl chloride identification bands is reported. Patch tests in this case were positive for three of four bands tested, resorcinol monobenzoate, and benzoyl peroxide. Manufacturers could not confirm the presence of resorcinol monobenzoate and benzoyl peroxide in their respective bands. It is concluded that the patient's reaction was allergic and due to an unknown chemical(s) in the bands. Additives may comprise a significant portion of polyvinyl chloride bands. These components may be leachable, and thus lead to contact sensitization with subsequent allergy. Although patch testing is an excellent first step in determining the offending allergen, specialized chemical analysis may be required for exact identification.

[A case of progressive right coronary ostial stenosis after Carrel patch method using gelatin-resorcin-formalin glue]

A 31-year-old man with type A chronic aortic dissection associated with annuloaortic ectasia underwent the concomitant graft replacement of the total aortic root and the transverse aortic arch. The two coronary arteries were reconstructed using the Carrel patch method. The false lumen of right coronary artery was closed by injection of GRF glue into the dissected space and compressing the dissected layers. Postoperative course was uneventful, and the patient has returned to normal daily life 2 months after surgery. Remarkable progression of the right coronary artery ostial stenosis was observed by coronary angiography 6 months after surgery. The remarkable progression of stenosis may occur in association with injection of GRF glue into the dissected space, although the exact etiology of the progressive stenosis remains obscure.

Treatment of melasma with Jessner's solution versus glycolic acid: a comparison of clinical efficacy and evaluation of the predictive ability of Wood's light examination

BACKGROUND

Melasma can be resistant to topical therapy.

OBJECTIVE

Our purpose was to evaluate the efficacy of superficial peels in conjunction with topical tretinoin and hydroquinone in patients with melasma and to evaluate the ability of Wood's light examination to predict response to treatment.

METHODS

We measured increased light reflectance in melasma areas with a colorimeter. Clinical observations were scored through an index designed to weigh numerically homogeneity, intensity of color, and area of melasma.

RESULTS

Colorimetric analysis showed an average lightening of 3.14 +/- 3.1 on the glycolic acid-treated side and 2.96 +/- 4.84 on the Jessner's solution-treated side. There was no statistically significant difference between the right and left. There was an overall decrease in melasma area and severity of 63%.

CONCLUSION

Superficial peels hasten the effects of topical therapy in melasma. Wood's light examination did not help predict response to treatment.