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1.
Contact Dermatitis ; 86(6): 524-530, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35150015

RESUMO

BACKGROUND: Preservatives are usually added to a wide array of consumer products to prevent growth of microbes and to prevent product destabilization and degradation. However, many of these preservatives are common skin sensitizers and may cause allergic contact dermatitis. The amount of preservatives may vary per country or region according to their respective legislation and may be reported in differences in prevalence rates of contact dermatitis. OBJECTIVE: To examine and identify preservatives in consumer products in accordance with Philippine legislation. To verify the accuracy of the list of ingredients of Philippine cosmetic products as legislated by the Philippine Bureau of Food and Drug Administration. METHODS: A total of 65 commonly used Philippine consumer products ranging from liquid facial and body washes, bar soaps, laundry detergents, feminine hygiene washes and wipes, shampoos and conditioners, sunblock, and moisturizers were selected. Ingredients noted on labels were documented. Products were subsequently investigated chemically for the presence of methylchloroisothiazolinone, methylisothiazolinone, or formaldehyde. RESULTS: The preservatives most commonly used in cosmetic products in the Philippine market are methylchloroisothiazolinone (MCI), methylisothiazolinone (MI), and/or formaldehyde. In accordance with Philippine legislation, almost all products provided a detailed ingredient list as printed on the packaging. Measurements of MCI/MI ranged from less than 1 ppm to 16 ppm, and MI ranged from only less than 1 ppm to 66 ppm, whereas formaldehyde was noted to range from less than 2.5 ppm to greater than 40 ppm in the products tested. Most products are manufactured by international brands, with a few products being manufactured locally. CONCLUSIONS: The preservatives found in cosmetic products were MCI, MI, and formaldehyde. Discrepancies were found in the preservatives and labeling of these products, with a majority of investigated Philippine products labeled inaccurately with varying concentrations of preservatives.


Assuntos
Cosméticos , Dermatite Alérgica de Contato , Cosméticos/efeitos adversos , Dermatite Alérgica de Contato/epidemiologia , Dermatite Alérgica de Contato/etiologia , Formaldeído , Humanos , Filipinas , Conservantes Farmacêuticos/efeitos adversos
2.
Contact Dermatitis ; 83(1): 8-18, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32087031

RESUMO

BACKGROUND: Most patients with contact allergy to Asteraceae plants are patch test positive to sesquiterpene lactone mix (SLM). There are several reports among these patients of a flare-up of hand eczema after ingestion of food and beverages originating from Asteraceae plants. AIM: To investigate whether German chamomile tea can elicit systemic allergic dermatitis. PATIENTS AND METHODS: Individuals with or without contact allergy to SLM were patch tested with an extract of German chamomile tea. Six weeks later, they were provoked with capsules containing either freeze-dried German chamomile tea or placebo capsules containing lactose, in a double-blind, randomized study. A numerical rating scale (NRS) was used to ascertain the volunteers' opinion of their hand eczema status. The study individuals were examined to detect a possible flare-up of healed patch test reactions to chamomile. RESULTS: None of the subjects had a flare-up of healed patch test reactions. According to the NRS, SLM-positive individuals experienced a significant worsening of hand eczema, independently of whether they received chamomile or lactose capsules. CONCLUSION: No evidence suggestive of systemic allergic dermatitis was found.


Assuntos
Dermatite Alérgica de Contato/etiologia , Ingestão de Alimentos , Dermatoses da Mão/etiologia , Matricaria/efeitos adversos , Preparações de Plantas/efeitos adversos , Adulto , Idoso , Estudos de Casos e Controles , Dermatite Alérgica de Contato/fisiopatologia , Método Duplo-Cego , Feminino , Dermatoses da Mão/fisiopatologia , Humanos , Lactonas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro , Preparações de Plantas/administração & dosagem , Distribuição Aleatória , Sesquiterpenos/efeitos adversos
3.
Contact Dermatitis ; 71(2): 92-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24720468

RESUMO

BACKGROUND: The possible impact of metal release from coronary artery stents has, with their increased use, become a concern. OBJECTIVES: To study in vitro metal release in biologically relevant milieu from coronary stents made of different alloys. MATERIALS AND METHOD: Coronary stents in common use in a department of cardiology at the time of the study were tested. A previously described in vitro technique was used, whereby the stents were kept in the extraction media for a week. Two different extraction media were used to show the necessity of studying the actual biological surrounding of the implant when metal release is investigated. Metal release was determined with atomic absorption spectrometry. RESULTS: In this study, we show metal release from stents after immersion in extraction media of artificial sweat and cysteine solution, as illustrative media. CONCLUSION: Metal release from coronary stents is shown. The magnitude of release is influenced by several factors. The extent to which metal release in vitro has potential biological effects, in terms of elicitation of an allergic reaction or induction of sensitization, in vivo needs to be explored. However, as metal release from an implant in a biologically appropriate medium has been established, better risk assessments in relation to delayed hypersensitivity may be undertaken.


Assuntos
Vasos Coronários , Dermatite Alérgica de Contato/etiologia , Haptenos/efeitos adversos , Haptenos/análise , Metais/efeitos adversos , Metais/análise , Stents/efeitos adversos , Humanos , Espectrofotometria Atômica
4.
Arterioscler Thromb Vasc Biol ; 32(3): 810-4, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22207727

RESUMO

OBJECTIVE: Cholesterol and lipoprotein metabolism display pronounced gender differences. Premenopausal women have lower LDL and higher HDL cholesterol, whereas men display higher synthetic rates of bile acids and cholesterol. The effects of the administration of exogenous hormones to humans and animals indicate that these gender differences can often be explained by estrogens. We evaluated how increased levels of endogenous estrogens modulate cholesterol and lipoprotein metabolism in women. METHODS AND RESULTS: We studied healthy women during initiation of in vitro fertilization using blood samples obtained when endogenous estrogens were low and high. Cholesterol in VLDL and LDL, but not in HDL, was reduced 20% when estrogens were high. Apolipoprotein B levels decreased 13%. Apolipoprotein A-I and triglyceride levels increased 8% and 37%, respectively, whereas lipoprotein(a) levels were unchanged. Circulating PCSK9, a suppressor of LDL receptors, was reduced 14% when estrogens were high. Serum markers of bile acid and cholesterol synthesis were unaltered. Growth hormone levels increased 3-fold when estrogens were high, whereas insulin-like growth factor-1 and fibroblast growth factor-21 concentrations were unaltered. CONCLUSION: In women, Apolipoprotein B-containing particles and circulating PCSK9 are reduced when endogenous estrogens are high, indicating that endogenous estrogens induce hepatic LDL receptors partly through a posttranscriptional mechanism. However, estrogens do not stimulate bile acid or cholesterol synthesis.


Assuntos
Ácidos e Sais Biliares/biossíntese , LDL-Colesterol/sangue , Estradiol/sangue , Lipoproteína(a)/sangue , Pró-Proteína Convertases/sangue , Serina Endopeptidases/sangue , Adulto , Apolipoproteínas B/sangue , Ácidos e Sais Biliares/sangue , Biomarcadores/sangue , Busserrelina/administração & dosagem , Regulação para Baixo , Feminino , Fármacos para a Fertilidade Feminina/administração & dosagem , Fertilização in vitro , Hormônio do Crescimento Humano/sangue , Humanos , Indução da Ovulação , Pró-Proteína Convertase 9 , Suécia
5.
Contact Dermatitis ; 69(3): 172-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23948034

RESUMO

BACKGROUND: For investigation of chemical exposure in allergic individuals, spot tests are invaluable. A reagent may react with a specific compound to give a specific typical colour, and thus indicate the presence of the specific substance. Spot tests can give both false-negative and false-positive reactions. To confirm the presence of the substance and quantify it, more sophisticated methods are required. On the basis of a positive cobalt spot test result, a woman was initially diagnosed with an occupational allergic contact dermatitis caused by cobalt. OBJECTIVES: To investigate cobalt release from three different metal weaves to which our patient was occupationally exposed. METHODS: The cobalt gel test and atomic absorption spectroscopy (AAS) were used to investigate the metal weaves. Two types of extract based on artificial sweat and nitric acid, respectively, were investigated with AAS. RESULTS: No cobalt release was demonstrated with AAS. CONCLUSIONS: When a diagnosis of allergic contact dermatitis caused by a sensitizer based on a positive spot test result will have far-reaching consequences, such as change of work, retraining, and claim on and payment of worker's compensation, conformational analysis must be performed.


Assuntos
Cobalto/imunologia , Dermatite Alérgica de Contato/etiologia , Dermatite Alérgica de Contato/imunologia , Dermatite Ocupacional/etiologia , Dermatite Ocupacional/imunologia , Exposição Ocupacional/efeitos adversos , Ligas/análise , Ligas/química , Cobalto/análise , Reações Falso-Positivas , Feminino , Humanos , Pessoa de Meia-Idade , Espectrofotometria Atômica
6.
BMC Nurs ; 12: 11, 2013 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-23574878

RESUMO

BACKGROUND: Knowledge of experiences from prostate cancer is sparse in a longitudinal perspective. From a nursing perspective, results from combined qualitative and quantitative studies are lacking however would present the broadest knowledge base for best practice. Present descriptions of medical-physical symptoms such as urinary, bowel and sexual dysfunction from quantitative inquiries need be complemented with qualitative results. Such knowledge is essential in relation to treatment and communication with patients over the years and not only shortly after surgery. METHODS: A longitudinal study was formatted to investigate general and specific health quality and sense of coherence quantitative alterations over three years. A general health quality module (EORTC QLC-C30) and a disease-specific module (EORTC PR-25) were applied for the longitudinal study together with the Orientation to life questionnaire (SOC), measuring a persons' sense of coherence. In order to strengthen reliability and compensate for low participation we used the Directed content analysis for interviewing and analysis. The method allows using findings from earlier research when interviewing along with detecting new areas. Twenty-one men were followed over three years and six of them, in the third year, accepted to be interviewed. RESULTS: We found high quality of life ratings and extended the study with follow-up interviews in year three, to investigate whether questionnaire results were in line with interview findings. We found high life quality and functioning ratings that were in line with qualitative descriptions. Interview analysis showed retrieval of life as lived before, yet in a different way, the men never forgot the diagnosis event, had a unique illness history worth hearing, and had come to terms with most treatment-related shortcomings. Sense of coherence ratings were medium to high and confirmed stability over time in comprehensibility, manageability and meaningfulness after prostate cancer treatment. CONCLUSIONS: Over the years, the men's negative experiences from shifted into 'a good life' though in a different way than before. The interpretation is supported in the study by quantitative results showing a high degree of functioning. The men's sense of coherence seamed to support their handling of life three years after prostate cancer treatment.

7.
Dermatitis ; 34(4): 323-328, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37001151

RESUMO

Background: Allergic contact dermatitis (ACD) caused by hexavalent chromium (Cr(VI)) is often severe and difficult to treat. The content of Cr(VI) in cement can be reduced by, for example, addition of iron(II) sulfate. Since 2005 the content of Cr(VI) in cement is regulated in the EU Directive 2003/53/EC and must not exceed 2 ppm. Since this regulation came into force, ACD caused by cement has markedly been reduced. Objective: To investigate Cr(VI) and total chromium content in samples of cement from countries within and outside the EU. Methods: The members of the International Contact Dermatitis Research Group (ICDRG) were invited to participate in the study with the aim to collect cement samples from geographically different areas. The content of Cr(VI) in the samples was estimated by the diphenyl carbazide spot test, atomic absorption spectroscopy was used to assess the total chromium content. Results: Forty-five cement samples were analyzed, containing amounts of Cr(VI) from <0.1 to >70 ppm. Twenty-one samples contained >2 ppm Cr(VI), 24 contained less. Four of 17 samples from within the EU contained >2 ppm Cr(VI), that is, higher amounts than stipulated in the EU directive, as compared with 17 samples from countries outside the EU. Conclusion: In countries outside the EU, significantly more cement samples contained >2 ppm Cr(VI).


Assuntos
Cromo , Dermatite Alérgica de Contato , Humanos , Cromo/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Cimentos Ósseos
8.
Clin Chem ; 58(8): 1225-32, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22679180

RESUMO

BACKGROUND: Hepcidin-25 reduces iron absorption by binding to the intestinal iron transporter ferroportin and causing its degradation. Currently, little is known about the basal regulation of circulating hepcidin-25. In addition, although erythropoietin administration has been reported to decrease the circulating hepcidin concentration, information is limited regarding how other stimulators of erythropoiesis, such as growth hormone (GH), might alter hepcidin-25 concentrations. METHODS: We used a sensitive and specific hepcidin-25 dual-monoclonal antibody sandwich immunoassay to measure hepcidin-25 in healthy human volunteers at various time points throughout the day and during 3 days of fasting and subsequent refeeding. We also measured hepcidin-25 concentrations in healthy volunteers after GH administration. RESULTS: In healthy individuals, hepcidin-25 concentrations displayed a diurnal variation, with concentrations being lowest in the early morning and steadily increasing throughout the day before declining during the evening hours, a pattern that was not influenced by food intake. Prolonged fasting produced statistically significant increases in hepcidin-25 concentrations. Refeeding reversed this process, and GH administration markedly decreased hepcidin-25 concentrations. CONCLUSIONS: Our results indicate that in humans, hepcidin-25 exhibits diurnal changes that can be altered by prolonged fasting, which increases hepcidin-25 concentrations approximately 3-fold after 3 days of fasting, possibly owing to a suppression of erythropoiesis that may occur during the fasting state to preserve tissue iron concentrations. In contrast, GH administration decreased hepcidin-25 concentrations by approximately 65%, presumably by stimulating erythropoiesis. These results indicate that circulating hepcidin-25 concentrations display much more dynamic and rapid variation than might have been anticipated previously.


Assuntos
Peptídeos Catiônicos Antimicrobianos/sangue , Ritmo Circadiano , Jejum , Hormônio do Crescimento Humano/uso terapêutico , Adulto , Idoso , Ensaio de Imunoadsorção Enzimática , Eritropoese , Hepcidinas , Humanos , Pessoa de Meia-Idade , Valores de Referência , Sensibilidade e Especificidade , Privação do Sono , Fatores de Tempo , Adulto Jovem
9.
Arterioscler Thromb Vasc Biol ; 30(12): 2666-72, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20884874

RESUMO

OBJECTIVE: To gain insight into the function of proprotein convertase subtilisin kexin type 9 (PCSK9) in humans by establishing whether circulating levels are influenced by diurnal, dietary, and hormonal changes. METHODS AND RESULTS: We monitored circulating PCSK9 in a set of dynamic human experiments and could show that serum PCSK9 levels display a diurnal rhythm that closely parallels that of cholesterol synthesis, measured as serum lathosterol. In contrast to these marked diurnal changes in cholesterol metabolism, serum low-density lipoprotein (LDL) cholesterol levels remained stable during the diurnal cycle. Depletion of liver cholesterol by treatment with the bile acid-binding resin, cholestyramine, abolished the diurnal rhythms of both PCSK9 and lathosterol. Fasting (>18 hours) strongly reduced circulating PCSK9 and lathosterol levels, whereas serum LDL levels remained unchanged. Growth hormone, known to be increased during fasting in humans, reduced circulating PCSK9 in parallel to LDL cholesterol levels. CONCLUSIONS: Throughout the day, and in response to fasting and cholesterol depletion, circulating PCSK9 displays marked variation, presumably related to oscillations in hepatic cholesterol that modify its activity in parallel with cholesterol synthesis. In addition to this sterol-mediated regulation, additional effects on LDL receptors may be mediated by hormones directly influencing PCSK9.


Assuntos
Colesterol/biossíntese , Ritmo Circadiano , Jejum/sangue , Serina Endopeptidases/sangue , Anticolesterolemiantes/administração & dosagem , Atorvastatina , Colesterol/sangue , LDL-Colesterol/sangue , Resina de Colestiramina/administração & dosagem , Estudos Cross-Over , Dieta Cetogênica , Regulação para Baixo , Ingestão de Energia , Feminino , Ácidos Heptanoicos/administração & dosagem , Hormônio do Crescimento Humano/administração & dosagem , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Pró-Proteína Convertase 9 , Pró-Proteína Convertases , Pirróis/administração & dosagem , Receptores de LDL/metabolismo , Suécia
10.
Thromb J ; 8: 4, 2010 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-20819203

RESUMO

BACKGROUND: Postoperative asymptomatic deep venous thromboses (ADVT) can give rise to posttthrombotic syndrome (PTS), but there are still many unresolved issues in this context. For example, there is a lack of knowledge regarding the fate of small ADVT following minor orthopedic surgery. This follow-up study evaluates postthrombotic changes and clinical manifestations of PTS in a group of patients with asymptomatic calf vein DVT after surgery for Achilles tendon rupture. METHODS: Forty-six consecutive patients with distal ADVT were contacted and enrolled in a follow-up consisting of a single visit at the hospital at a mean time of 5 years postoperatively, including clinical examination and scoring, ultrasonography and venous plethysmography. All patients had participated in DVT-screening with colour duplex ultrasound (CDU) 3 and 6 weeks postoperatively and 80% of them were treated with anticoagulation. RESULTS: With CDU postthrombotic changes and deep venous reflux were detected at follow-up in more than 50% of the patients, more commonly in somewhat larger calf DVT:s initially affecting more than one vessel. However, only about 10% of the patients had significant venous reflux according to venous plethysmography. No patient had plethysmographic evidence of remaining outflow obstruction, but presence of postthrombotic changes shown with CDU negatively influenced venous outflow capacity measured with plethysmography. A clinical entity of PTS was rarely found and occurred only in two patients (4%) and then classified by Villalta scoring as of mild degree with few clinical signs of disease. Distal ADVT:s detected in the early postoperative period (3 weeks) showed DVT-progression in 75% of the limbs that were still immobilized and without anticoagulation. CONCLUSIONS: Asymptomatic postoperative distal DVT:s following surgery for Achilles tendon rupture have a good prognosis and a favourable clinical outcome. In our material of 46 patients the general appearance of the clinical entity of PTS at 5 years follow-up was low (<5%). Morphological and functional abnormalities were mainly seen in those patients that initially had somewhat larger distal DVT:s involving more than one deep calf vein segment.

13.
J Clin Periodontol ; 36(7): 541-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19538326

RESUMO

AIM: Studies have reported on an association between cardiovascular disease (CVD) and periodontitis. The purpose of this case-control study was to provide an insight into this association by determining the plasma levels of some risk markers for CVD in cases with periodontitis. MATERIALS AND METHODS: Sixty-eight cases with periodontitis, mean age 53.9 (SD 7.9) years, and 48 randomly selected healthy controls, mean age 53.1 (SD 7.9) years, were investigated. Fasting blood plasma was analysed for glucose, lipids, markers systemic inflammation, cytokines and antibodies against heat shock proteins (Hsp). The associations between periodontitis and the various substances analysed in plasma were calculated using a multivariate logistic regression model, which compensated for age, gender, smoking and body mass index. RESULTS: The regression analyses revealed a significant association between periodontitis and high levels of C-reactive protein (CRP) [odds ratio (OR) 4.0, confidence interval (CI) 1.4-11.4] and fibrinogen (OR 8.7, CI 2.6-28.4), IL-18 (OR 6.5, CI 2.2-19.5), and decreased levels of IL-4 (OR 0.12, CI 0.0-0.5). The study showed increased levels of antibodies against Hsp65 (OR 2.8, CI 1-7.6) and 70 (OR 2.9, CI 1.1-7.8) and decreased levels of antibodies against Hsp60 (OR 0.3, CI 0.1-0.8). CONCLUSIONS: Periodontitis was associated with increased levels of CRP, glucose, fibrinogen and IL-18, and with decreased levels of IL-4.


Assuntos
Aterosclerose/sangue , Proteína C-Reativa/análise , Fibrinogênio/análise , Periodontite/sangue , Adulto , Idoso , Aterosclerose/complicações , Aterosclerose/imunologia , Autoanticorpos/sangue , Glicemia/análise , Estudos de Casos e Controles , Feminino , Proteínas de Choque Térmico/imunologia , Humanos , Interleucina-18/sangue , Interleucina-4/sangue , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Periodontite/complicações , Periodontite/imunologia , Valores de Referência , Análise de Regressão , Fatores de Risco , Índice de Gravidade de Doença
15.
Contact Dermatitis ; 60(5): 270-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19397619

RESUMO

BACKGROUND: Former investigations have demonstrated that patch test preparations containing Disperse Blue (DB) 106 and DB 124 are impure. OBJECTIVE: To investigate the significance of impurities in preparations of disperse dyes with regard to contact allergy. MATERIALS/METHODS: 21 patients allergic to DB 106 and/or DB 124 were tested with dilution series of commercial and purified DB 106 and DB 124. All patients were additionally tested with thin-layer chromatography (TLC) strips made from the commercial preparations containing DB 106 and 18 of them also with TLC strips containing DB 124. RESULTS: 13 of 21 and 12/18 patients tested positively to the strips of DB 106 and DB 124, respectively. Among these patients, 4/13 and 5/12, respectively, did not react to the main spot but reacted to other spots. Dilution series of purified DB 106 and DB 124 were positive in 10 patients each, while 16 and 15 patients, respectively, tested positively to the dilution series of the corresponding commercial disperse dye. CONCLUSION: Approximately 25% of the patients, diagnosed as contact allergic to DB 106 and DB 124, only reacted to impurities in the patch test preparations. This has implications for diagnosis and prevention.


Assuntos
Compostos Azo/toxicidade , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/etiologia , Contaminação de Medicamentos , Testes do Emplastro/métodos , Adulto , Idoso , Cromatografia em Camada Fina , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro/normas , Padrões de Referência , Suécia
18.
Dermatitis ; 30(4): 259-263, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31261225

RESUMO

BACKGROUND: Nail polish is known to contain potentially hazardous chemicals that have been linked to adverse health effects after overexposure. Formaldehyde is used as an antimicrobial, preservative, and nail hardener in select nail products, yet it is a recognized carcinogen and potent allergen in allergic contact dermatitis. OBJECTIVE: The aim of this study was to investigate whether formaldehyde is present in nail polishes marketed as formaldehyde-free. METHODS: Twenty-nine cosmetic nail polishes were purchased for analysis; of these, 28 were advertised as formaldehyde-free and/or did not declare formaldehyde in their ingredient lists. Initial testing was pursued using the chromotropic acid method, which uses a red-purple color change to indicate the presence of formaldehyde. Products were subsequently analyzed at least twice using high-performance liquid chromatography, quantifying formaldehyde amount above the detection limit of 2 ppm. CONCLUSIONS: High-performance liquid chromatography analysis found 5 of 29 products containing formaldehyde, 4 of which were advertised as formaldehyde-free. All other products were negative for formaldehyde (<2 ppm). Further investigation is warranted among brands testing positive and whether multiple products within the same line contain formaldehyde. Nail products must be labeled appropriately to avoid adverse reactions among individuals with cutaneous sensitivities.


Assuntos
Alérgenos/análise , Cosméticos/química , Formaldeído/análise , Rotulagem de Produtos , Dermatite Alérgica de Contato/etiologia , Humanos , Naftalenossulfonatos/análise , Solventes/análise
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