Low-dose hexavalent chromium induces mitophagy in rat liver via the AMPK-related PINK1/Parkin signaling pathway.

Hexavalent chromium (Cr(VI)) is a hazardous metallic compound commonly used in industrial processes. The liver, responsible for metabolism and detoxification, is the main target organ of Cr(VI). Toxicity experiments were performed to investigate the impacts of low-dose exposure to Cr(VI) on rat livers. It was revealed that exposure of 0.05 mg/kg potassium dichromate (K2Cr2O7) and 0.25 mg/kg K2Cr2O7 notably increased malondialdehyde (MDA) levels and the expressions of P-AMPK, P-ULK, PINK1, P-Parkin, and LC3II/LC3I, and significantly reduced SOD activity and P-mTOR and P62 expression levels in liver. Electron microscopy showed that CR(VI) exposure significantly increased mitophagy and the destruction of mitochondrial structure. This study simulates the respiratory exposure mode of CR(VI) workers through intratracheal instillation of CR(VI) in rats. It confirms that autophagy in hepatocytes is induced by low concentrations of CR(VI) and suggest that the liver damage caused by CR(VI) may be associated with the AMPK-related PINK/Parkin signaling pathway.

Chlorogenic acid mitigates potassium dichromate-induced acute hepato-nephrotoxicity by attenuating the NF-κB signalling pathway.

BACKGROUND: Hexavalent chromium (CrVI) is known to be a potentially hepatotoxic and nephrotoxic contaminant in humans and other animals, whose toxicity is associated with oxidative stress and inflammation. The aim of this study was to evaluate the potential protective effect of chlorogenic acid (CGA), which has known anti-inflammatory and antioxidant effects, on potassium dichromate (PDC)-induced acute hepatotoxicity and nephrotoxicity in rats. METHODS AND RESULTS: Thirty-six Wistar albino rats were treated with CGA (10, 20, or 40 mg/kg, intraperitoneally) and/or PDC (15 mg/kg/day, intraperitoneally) as a single dose. Serum, liver, and kidney tissues were examined biochemically, histopathologically, and immunohistochemically. Compared to the control group, a significant increase in interleukin-6 (IL-6) levels and a significant decrease in serum and renal reduced glutathione (GSH) levels, liver catalase (CAT), tumour necrosis factor-alpha (TNF-α), and interleukin 1ß (IL-1ß) levels were observed in the PDC group. The administration of PDC led to histopathological and immunohistochemical changes in rat liver and kidney tissues. With the administration of CGA, especially at the 10 mg/kg dosage, the above-mentioned parameters approached normal levels. CONCLUSIONS: CGA had antioxidant and anti-inflammatory effects that alleviated PDC-induced acute hepato- and nephrotoxicity.

Potassium dichromate sensitivity presenting as tefillin dermatitis: A retrospective cohort study.

BACKGROUND: Tefillin are a religious article worn by Jewish men during daily prayer. Tefillin dermatitis secondary to potassium dichromate sensitivity is recognised, but data remain sparse. OBJECTIVE: To investigate the prevalence and clinical characteristics of tefillin dermatitis. METHODS: Patients who underwent patch testing with the European baseline series in a tertiary dermatology clinic in 2009-2023 and were diagnosed with tefillin dermatitis were identified by file review and their clinical data recorded. RESULTS: Of 1679 consecutive male patients tested, 25 (1.49%) were diagnosed with tefillin dermatitis, accounting for 15.34% of all potassium-dichromate-positive patients (163/1679). Mean pre-symptomatic duration of tefillin use was 38 ± 16.9 years, and mean follow-up time, 3.1 ± 2.9 years. Patients presented with an eczematous rash on body areas in direct contact with the leather box or straps of the tefillin. An id reaction was noted in 32%, and sensitivity to other leather accessories, in 44%. Fourteen patients (56%) switched to chromate-free tefillin: symptoms resolved completely in 11 (79%) and partially in 2. LIMITATIONS: Retrospective cohort design. CONCLUSION: This is the largest study to date of tefillin dermatitis caused by sensitivity to potassium dichromate used in leather production. Prognosis after switching to chromate-free tefillin was good-to-excellent. Tefillin dermatitis may be more prevalent than previously thought.

Reno-protective effect of nicorandil and pentoxifylline against potassium dichromate-induced acute renal injury via modulation p38MAPK/Nrf2/HO-1 and Notch1/TLR4/NF-κB signaling pathways.

BACKGROUND: Occupational and environmental exposure to chromium compounds such as potassium dichromate (PDC) (K2Cr2O7) has emerged as a potential aetiologic cause for renal disease through apoptotic, and inflammatory reactions. The known potent antioxidants such as nicorandil (NIC) and/or pentoxifylline (PTX) were studied for their possible nephroprotective effect in PDC-treated rats. METHODS: Forty male Wistar rats were divided into five groups; control, PDC group, NIC+PDC, PTX+PDC group, and combination+PDC group. Nephrotoxicity was evaluated histopathologically and biochemically. Invasive blood pressure, renal function parameters urea, creatinine, uric acid and albumin, glomerular filtration rate markers Cys-C, Kim-1 and NGAL, inflammatory markers IL-1ß, IL-6, TNF-α, TGF-ß, COX-II, p38MAPK, NF-κB and TLR4, oxidative stress SOD, GSH, MDA, MPO, HO-1 and Nrf2 and apoptotic mediators Notch1 and PCNA were evaluated. Besides, renal cortical histopathology was assayed as well. RESULTS: PDC led to a considerable increase in indicators for kidney injury, renal function parameters, invasive blood pressure, oxidative stress, and inflammatory markers. They were markedly reduced by coadministration of PDC with either/or NIC and PTX. The NIC and PTX combination regimen showed a more significant improvement than either medication used alone. Our results demonstrated the nephroprotective effect of NIC, PTX, and their combined regimen on PDC-induced kidney injury through suppression of oxidative stress, apoptosis, and inflammatory response. CONCLUSION: Renal recovery from PDC injury was achieved through enhanced MAPK/Nrf2/HO-1 and suppressed Notch1/TLR4/NF-κB signaling pathways. This study highlights the role of NIC and PTX as effective interventions to ameliorate nephrotoxicity in patients undergoing PDC toxicity.

The possible protective role of selenium on the visual cortex of adult albino rat on exposure to potassium dichromate.

The visual cortex is very important in mammals for processing of visual information. Exposure to heavy metals such as potassium dichromate poses serious health threat to human beings. The aim of this work is to study the effect of potassium dichromate on the visual cortex of adult albino rat and also to identify the possibility of selenium as protective agent against toxicity of potassium dichromate. A total number of 40 adult albino rats weighting (200-250) gm were used. They divided into four groups: control group, potassium dichromate received group, potassium dichromate and selenium received group and selenium received group. The rats received treatment for 6 weeks. After 6 weeks, they were sacrificed. The present study showed that potassium dichromate causes degeneration of granular neurons in layer IV and pyramidal neurons in layer V. Morphometric results revealed statistically significant decrease in the number of granule and pyramidal cells in potassium dichromate received group as compared with control group. Most of degenerative changes are improved by selenium.

الدور الوقائي المحتمل للسيلينيوم على القشرة المخية البصرية للفأر الابيض البالغ عند التعرضللدايكرومات البوتاسيومسالي سيد أنور-هالة محمد حسانينقسم التشريح الادمي وعلم الاجنة -كلية الطب البشرى- جامعة اسيوطالقشرة البصرية مهمة جدا في الثدييات لمعالجة المعلومات المرئية. يشكل التعرض للمعادنالثقيلة مثل ثنائي كرومات البوتاسيوم تهديداً صحياً خطيراً للإنسان. الهدف من هذا العمل هودراسة تأثير ثنائي كرومات البوتاسيوم على القشرة البصرية لجرذ ألبينو البالغ وكذلك التعرفعلى إمكانية استخدام السيلينيوم كعامل وقائي ضد سمية ثنائي كرومات البوتاسيوم. تم استخدامجرذ من الجرذان البالغة وزنها (200-250) جرام. تم تقسيمهم إلى 4 مجموعات: المجموعة40الضابطة ، المجموعة المستلمة ثنائي كرومات البوتاسيوم ، المجموعة المستلمة ثاني كروماتالبوتاسيوم والسيلينيوم المجموعة المستلمة سيلينيوم تلقتالفئران العلاج لمدة 6أسابيع. بعد ستة أسابيع تم التضحية بهم. أظهرت الدراسة الحالية أن ثنائي كرومات البوتاسيوميسبب تنكس الخلايا العصبية الحبيبية في الطبقة الرابعة والخلايا العصبية الهرمية في الطبقةالخامسة. أظهرت نتائج القياس المورفومتري انخفاضًا ذا دلالة إحصائية في عدد الخلايا الحبيبيةوالهرمية في المجموعة التي تم تلقيها من ثنائي كرومات البوتاسيوم مقارنة بمجموعة التحكم. يتمتحسين معظم التغييرات التنكسية بواسطة السيلينيوم.[Figure: see text].

Anti-inflammatory, anticholinesterase, antioxidant, and memory enhancement potential of Phyllanthus amarus in potassium-dichromate induced neurotoxicity of male Wistar rats.

This study investigated the protective effect of aqueous Phyllanthus amarus leaf extract (APALE) in Potassium dichromate (PDc)-induced neurotoxicity. Seventy young adult male, Wistar rats with a weight of 130-150 g, were randomised into seven groups (n = 10): Group 1; distilled water; Group 2: 300 mg/kg APALE; Group 3: 17 mg/kg PDc; Group 4: 5 mg/kg Donepezil (DPZ); Group 5: 17 mg/kg PDc + 400 mg/kg APALE; Group 6:17 mg/kg PDc + 200 mg/kg APALE; Group 7: 17 mg/kg PDc + 5 mg/kg DPZ. All administrations were given once daily via an orogastric cannula for 28 consecutive days. Cognitive assessment tests were employed to ascertain the treatments' effects on the rats' cognitive function. At the end of the experiment, the rats were sacrificed, morphometric analysis was done, and the brains were dissected for histology, enzyme, and other biochemical analysis. Findings from this study showed that APALE significantly improved locomotive activity, recognition memory sensitivity, protection against fear and anxiety, enhanced decision-making, and improved memory function in a dose-dependent manner comparably to DPZ. In addition, APALE significantly increased antioxidants level, reducing oxidative stress in PDc-induced neurotoxic rats and significantly reducing brain acetylcholinesterase (AchE) activity by regulating gamma amino butyric acid (GABA) levels in PDc-induced neurotoxic rats compared to DPZ. Furthermore, APALE alleviated neuroinflammatory responses via maintaining histoarchitecture and down-regulation of IBA1 and Tau in PDc-induced rats. In conclusion, APALE protected against PDc-induced neurotoxicity via a combination of anti-inflammatory, anticholinergic, and antioxidant effects on the prefrontal cortex of rats.

Beneficial effects of mate-herb, Ilex paraguariensis St. Hil. against potassium dichromate-induced oxidative stress and nephrotoxicity.

Chimarrão is a typical beverage made from the infusion of dried and ground leaves and stems of Ilex paraguariensis (popularly known as Yerba mate or mate herb) which is widely consumed in parts of South America. The aim of this study was to examine the effects of the chimarrão against nephrotoxicity and oxidative stress induced by the potassium dichromate (PD) salt in male Wistar rats. The experiment lasted 17 days, and in the first 15 days animals ingested a chimarrão infusion or control drinking water and then submitted to an intraperitoneal injection (15 mg/kg) of PD (or saline solution) and euthanized after 48 hr at which time animals still received infusion or drinking water. Blood plasma and 24 hr-urine samples were collected to measure creatinine levels as an estimate of glomerular filtration rate (GFR). Concomitantly oxidative stress was determined in the kidneys as evidenced by levels of carbonyl groups, malondialdehyde (MDA) and antioxidant capacity against peroxyl radicals. Potassium dichromate induced oxidative stress in the kidneys and reduced GFR. Treatment with chimarrão during the 15 days prior to PD injection reduced PD salt-mediated oxidative stress. Further, treatment with post-injection chimarrão to PD-administered rats improved the GFR. Our findings support that the use of the chimarrão beverage may be considered as an important nephroprotective substance.

Combined ß-sitosterol and trimetazidine mitigate potassium dichromate-induced cardiotoxicity in rats through the interplay between NF-κB/AMPK/mTOR/TLR4 and HO-1/NADPH signaling pathways.

Hexavalent chromium salt, like potassium dichromate (PD), is chromium's most precarious valence state in industrial wastes. Recently, there has been increasing interest in ß-sitosterol (BSS), a bioactive phytosterol, as a dietary supplement. BSS is recommended in treating cardiovascular disorders due to its antioxidant effect. Trimetazidine (TMZ) was used traditionally for cardioprotection. Through the administration of BSS and TMZ, the cardiotoxic effects of PD were to be countered in this study, in addition to examining the precise mechanism of PD-induced cardiotoxicity. Thirty male albino rats were divided into five groups; the control group: administered normal saline daily (3 mL/kg); the PD group: administered normal saline daily (3 mL/kg); BSS group: administered BSS daily (20 mg/kg); TMZ group: administered TMZ daily (15 mg/kg); and the BSS + TMZ group: administered both BSS (20 mg/kg) and TMZ (15 mg/kg) daily. All experimental groups, except the control, received on the 19th day a single dose of PD (30 mg/kg/day, S.C.). Normal saline, BSS, and TMZ were received daily for 21 consecutive days p.o. The exposure to PD promoted different oxidative stresses, pro-inflammatory, and cardiotoxicity biomarkers. BSS or TMZ succeeded solely in reducing these deleterious effects; however, their combination notably returned measured biomarkers close to normal values. The histopathological investigations have supported the biochemical findings. The combination of BSS and TMZ protects against PD cardiotoxicity in rats by reducing oxidative stress and apoptotic and inflammatory biomarkers. It may be promising for alleviating and protecting against PD-induced cardiotoxicity in people at an early stage; however, these findings need further clinical studies to be confirmed. HIGHLIGHTS: • Potassium dichromate induces cardiotoxicity in rats through the upregulation of oxidative stress, proinflammatory, and apoptotic pathways biomarkers. • ß-Sitosterol possesses a possible cardioprotective effect by modulating several signaling pathways. • Trimetazidine, the antianginal agent, has a potential cardioprotective impact on PD-intoxicated rat model. • The combination of ß-Sitosterol and trimetazidine was the best in modulating different pathways involved in PD cardiotoxicity in rats via the interplay between NF-κB/AMPK/mTOR/TLR4 and HO-1/NADPH signaling pathways.

Appraisal of the Pre-Emptive Effect of Lactoferrin Against Chromium-Induced Testicular Toxicity in Male Rats.

Lactoferrin (LCF), a potent naturally occurring antioxidant, is a crucial component in preventing potassium dichromate (PDC) toxicity. The goal of the current work was to study the potential efficacy of LCF in preventing PDC(CrVI)-induced testicular toxicity and oxidative injury in rats. Six groups of male rats of Wistar stain were randomly categorized into: group 1, which served as the control; group 2 and 3 received LCF (200 and 300 mg/kg orally, respectively); group 4 received PDC (2 mg/kg i.p.); group 5 and 6 pretreated with LCF, followed by PDC as in group 4 with 90 min apart for 28 days. PDC-intoxicated rats showed a significantly altered spermogram with abnormal sperm morphology. PDC significantly upregulated serum FSH and downregulated testosterone levels. Additionally, PDC decreased the levels of testicular key antioxidant biomarkers (catalase (CAT), superoxide dismutase (SOD), and glutathione (GSH)) with elevated lipid peroxidation marker (TBARS) and testicular chromium content. Moreover, it upregulated testicular proinflammatory cytokines, IL-1, IL-6, IL-10, and TNF-α, induced histopathological changes in testes with significant immunohistochemical expression of FasL and moderate expression of Nrf2. Pretreatment with LCF significantly mitigated PDC-induced testicular toxicity by enhancing spermogram, improving hormonal levels, restoring testicular oxidant/antioxidant balance, and decreasing testicular IL-1, IL6, IL-10, and TNFα levels, and amending both FasL and Nrf2 immunohistochemical-expression. Additionally, LCF improved testicular histopathological picture and spermatogenesis. Our results highlight the importance of LCF as a superior protective modulator of PDC-induced testicular injury.

Modulation of quorum sensing activity by copper sulfate, potassium dichromate, and cadmium chloride in biosensor strains.

Beyond their biological roles, metals have a strong impact on the environment. It has been reported that metals are also inhibitory of Quorum Sensing (QS) mechanisms, ones of the best characterized signaling systems in bacteria and fungi. We analyzed the effect of CuSO4, CdCl2, and K2Cr2O7, on QS systems sharing or differing in the bacterial host or the QS signal. The results in this study show that CuSO4 can not only be inhibitory, but also stimulatory of QS activity: at 0.2 mM increased six fold the activity in Chromobacterium subtsugae CV026. This behavior is related to the concentration of the metal and the particular QS system: E. coli MT102 (pJBA132) was no affected, but CuSO4 decreased the QS activity of Pseudomonas putida F117 (pKR-C12) to half its control values. K2Cr2O7 increased four and three folds the QS activities of E. coli MT102 (pJBA132) and P. putida F117 (pAS-C8), respectively, but without effect when combined with CuSO4 or CdCl2. CdCl2 only showed a positive effect in CV026 when combined with CuSO4. Results suggest that factors related with the culture conditions impact on the influence of the metals, and reinforce the importance of the environment in the modulation of QS activity.

Chronic actinic dermatitis: A 5-year clinical analysis of 488 patients in China.

BACKGROUND/PURPOSE: Chronic actinic dermatitis (CAD) is a spectrum of diseases with chronic photosensitivity occurring mostly among middle-aged and older men. We seek to explore the characteristics and pathogenesis of CAD among the Chinese population. METHODS: The medical records of 488 CAD cases diagnosed by phototesting at Huashan Hospital, Fudan University from January 2014 to December 2018 were analyzed retrospectively. RESULTS: Among the 488 patients, 344 were male and 144 were female. 84.8% of the cases were over 40 years old at the age of onset, while the remaining with an early age of onset had a prevalence of atopic history of 21.6%. Up to 45.0% of the patients reported excessive sun exposure and outdoor activities before the initiation of symptoms. The typical skin lesions were erythema, papules and plaques laid predominantly in sun-exposed areas. 42.8% of the cases showed sensitivity to UVB only, 20.7% were both sensitive to UVA and UVB, and 18.2% had UVA sensitivity only. The most predominant photoallergens were chlorpromazine (80.1%), thimerosal (17.2%), potassium dichromate (12.7%), etc. The most prevalent patch test allergens were potassium dichromate (24.4%), thimerosal (20.5%), formaldehyde (16.8%), etc. CONCLUSIONS: CAD was more commonly seen in males over 40 years old. The action spectrum of Chinese patients is primarily in the UVB range. Exposure to excessive sunlight or contact allergens and photoallergens are important risk factors. Photobiology tests are essential in detecting photosensitivity and recognizing potential photosensitizers. Early avoidance of confirmed photoallergens and sun exposure may prevent photosensitive reactions from progressing into persistent photosensitivity.

The Penetration of Chromium: An Up-To-Date 0.5% Potassium Dichromate Vehicle Comparison.

BACKGROUND: Chromium (Cr) contact allergy is frequent in many industrialized countries. The knowledge of the factors that can influence percutaneous penetration is very important assessing the risk of human exposure. OBJECTIVE: The aim of the study was to compare the concentration of Cr in various skin layers using 2 different vehicles. METHODS: Full-thickness (approximately 1 mm) porcine ear skin was mounted in Franz-type diffusion cells. Duplicate potassium dichromate preparations in 0.5% petrolatum (pet) and 0.5% in aqua (aq) were applied to the donor compartment facing the epidermis for 24 hours. After the experiment, the porcine skin samples were cut with a microtome. All samples were analyzed for total Cr concentration by inductively coupled plasma sector field mass spectrometry. The limit of detection was 0.001 µg/cm3. RESULTS: Chromium was detected in both recipient phases. The distribution of Cr in the skin is similar for pet and aq preparations, but the concentration of Cr detected in the skin was almost 2 times lower for pet comparing aq preparations. CONCLUSIONS: Both vehicles were suitable for penetrating the skin. Less Cr is found in the skin when pet is used as a vehicle. Acid wipe sampling and finger immersion test results might be false-negative for Cr in occupations involving contact with Cr salts in aq solutions.

Nephroprotective role of Echinacea purpurea against potassium dichromate-induced oxidative stress, inflammation, and apoptosis in rats.

Environmental and occupational exposure to chromium compounds, especially hexavalent chromium [Cr(VI)], is widely recognized as a potential nephrotoxic in humans and animals. Its toxicity is associated with the overproduction of free radicals, which induces oxidative damage. Echinacea purpurea (L.) Moench is an herbaceous perennial plant rich in phenolic components and frequently used for its medicinal benefits. The current work evaluated the effectiveness of E. purpurea (EP) against oxidative stress and nephrotoxicity induced by potassium dichromate in male rats. Male Wistar rats were divided into four groups: control, E. purpurea (EP; 50 mg/kg; once daily for 3 weeks), hexavalent chromium (Cr(VI); 15 mg/kg; single intraperitoneal dose), and EP + Cr(VI) where rats were pretreated with EP for 3 weeks before receiving CrVI, respectively. Results revealed that rats exposed to Cr(VI) showed a significant increase in PC, TBARS, and H2 O2 , kidney function biomarkers (Urea, creatinine, and uric acid), lactate dehydrogenase activity (LDH), TNF-α, IL-18, nuclear factor kappa B (NFκB), and IGF-1 (Insulin-like growth factor-1) levels as well as a considerable decline in metallothionein (MT), glutathione (GSH) content, enzymatic antioxidants (SOD, CAT, GPx, GR, and GST), alkaline phosphatase (ALP) activities, and protein content. Cr(VI) induced apoptosis in kidney tissues as revealed by upregulation of Bax and caspase 3 and downregulation of Bcl-2. Furthermore, EP treatment ameliorated the Cr(VI)-induced histopathological and ultrastructure variations of kidney tissue, which was confirmed by the biochemical and molecular data. It is clear from the results of this study that EP exerts nephroprotective effects by improving the redox state, suppressing inflammatory reaction and cell apoptosis as well as ameliorating the performance of kidney tissue architecture, which is eventually reflected by the improvement of kidney function in rats.

Comparison between patch test results of natural dyes and standard allergens in batik workers with occupational contact dermatitis.

BACKGROUND: Occupational contact dermatitis (OCD) is a skin disorder caused by contact with any substances found in the workplace. Occupational contact dermatitis is second most common occupational disease (15% of all cases of occupational disease). Occupational contact dermatitis is divided into allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD) which is 80% of cases that affects hands. Batik is an art that is painted on cloth, it is one of Indonesian cultural heritage. Batik workers have a higher risk of obtaining OCD due to exposure to chemicals and fluids used during work. Natural dyes used in the dyeing process are less likely to cause ACD than standard allergens. Some of the natural dyes used in the dyeing process in batik industries are Indigofera tinctoria, sappan wood (Caesalpinia sappan), and Mahagony (Swietenia mahagoni) cause skin sensitisation. OBJECTIVE: To compare the results of patch testing between natural dyes (Indigofera tinctoria, sappan wood (Caesalpinia sappan), and Mahagony (Swietenia mahagoni) with standard allergens (p-phneyldiamine 0.1%, potassium dichromate 0.5% and formaldehyde 0.1%) as a cause of ACD in batik workers in Surakarta, East Java, Indonesia. METHOD: A cross-sectional study was conducted on 63 subjects batik workers with OCD in Surakarta, East Java, Indonesia. Subjects were patch tested with three standard allergens (p-phenylenediamine 0.1%, potassium dichromate 0.5%, and formaldehyde 1%) and natural dyes (Indigofera tinctoria, sappan wood (Caesalpinia sappan), and Mahagony (Swietenia mahagoni). A closed patch test was evaluated 48 and 96 hour later. Screening of OCD in batik workers in Surakarta, East Java, Indonesia was based on Nordic Occupational Skin Questionnaire NOSQ-2002, and diagnosis of OCD was based on Mathias criteria (at least 4 out of 7 criteria were met). Data were analysed using a non-parametric Chi-square test with SPSS 21 with a significant difference if the p-value < 0.05. RESULT: Natural dyes significantly caused allergic contact dermatitis in batik workers in Surakarta, East Java, Indonesia than standard allergens (p = 0.016). A positive patch test was found in 11 patients, standard allergen p-phenylenediamine (PPD) 0.1% was seen on one patient, potassium dichromate 0.5% on two patients, and formaldehyde 1% on two patients. A positive patch test using Indigofera tinctoria was found at one patient, sappan wood (Caesalpinia sappan) in three patients, and Mahagony (Swietenia mahagoni) in five patients. CONCLUSION: Natural dyes cause more positive patch test results in batik workers.

Contact allergy in children with and without atopic dermatitis: An Italian multicentre study.

BACKGROUND: Contact allergy and atopic dermatitis (AD) are both common inflammatory T cell-mediated diseases and many factors may influence the prevalence of contact allergy in AD patients. In children, their possible correlation was debated with conflicting results. OBJECTIVES: The present study aimed to assess the prevalence of contact sensitivity in children and to investigate the association with AD. MATERIALS AND METHODS: A retrospective multicentre study on children aged from 0 to 14 years patch tested between January 2017 and December 2018 was performed. Children were consecutively patch tested with the SIDAPA (Società Italiana Dermatologia Allergologica Professionale Ambientale) baseline series. RESULTS: Among the 432 children investigated for contact allergy, 125 (28.9%) showed a positive reaction to at least one of the allergens tested, with a higher prevalence of positive patch test reactions in girls (32.3%) than in boys (25.0%). The most frequent contact allergens were nickel sulphate (10.2%), cobalt chloride (6.7%), methylisothiazolinone (3.7%), fragrance mix-2 (3.2%), potassium dichromate (2.8%), fragrance mix-1 (2.1%) and methylchloroisothiazolinone/methylisothiazolinone (2.1%). One-hundred-three children (23.8%) suffered from AD showing a higher prevalence of positive patch test (36.9%) compared to children without AD (26.4%). CONCLUSIONS: Despite the topic being still controversial, the present study suggests a consistent prevalence of contact allergy among children with higher sensitivity rate among children with AD than without AD.

Pattern of contact sensitization in patients with and without atopic dermatitis in an Asian dermatology center.

BACKGROUND: Although the traditional understanding is that contact sensitization is less frequent in patients with atopic dermatitis (AD), recent studies have shown similar or higher rates of positive patch-test results in AD patients. OBJECTIVES: We sought to characterise the pattern of contact sensitization in patients with and without AD and evaluate the association between AD and contact sensitization. METHOD: This was a single-center, 10-year retrospective review of patients who underwent patch testing between 2007 and 2017. RESULTS: There were 4903 patients (male-to-female ratio = 1:1.4; mean age 40.1 years) included. About half (2499, 51.0%) of all patients developed at least one positive reaction. The top five frequent reactions were to nickel sulfate (45.4%), potassium dichromate (16.0%), p-phenylenediamine (13.4%), Myroxylon pereirae (11.8%), and fragrance mix I (11.2%). The overall prevalence of contact sensitization was not significantly different between patients with or without AD. Patients with AD were less likely to develop contact allergies to budesonide and thiuram mix, and more likely to develop contact allergies to potassium dichromate. CONCLUSIONS: Contact sensitization was detected in 50% of patients who were patch tested. Nickel sulfate was the most frequently sensitizing allergen. The prevalence of contact allergies in atopic patients is comparable to that in non-atopic patients.

Nephroprotective Efficacy of Selenium and Zinc Against Potassium Dichromate-Induced Renal Toxicity in Pregnant Wistar Albino Rats.

Hexavalent chromium (CrVI) compounds are potent toxicants commonly used in numerous industries. Thus, potential toxic effects and health hazards are of high relevance. Selenium (Se) and zinc (Zn) are known for their antioxidant and chemoprotective properties. However, little is known about their protective effects against CrVI-induced renal damage during pregnancy. In this context, the present study aimed to investigate the protective efficacy of these two essential elements against potassium dichromate-induced nephrotoxicity in pregnant Wistar Albino rats. Female rats were divided into control and four treated groups of six each receiving subcutaneously on the 3rd day of pregnancy, K2Cr2O7 (10 mg/kg, s.c. single dose) alone, or in association with Se (0.3 mg/kg, s.c. single dose), ZnCl2 (20 mg/kg, s.c. single dose) or both of them simultaneously. The nephrotoxic effects were monitored by the evaluation of plasma renal parameters, oxidative stress biomarkers, DNA damage, and renal Cr content. The obtained results showed that K2Cr2O7 disturbed renal biochemical markers, induced oxidative stress and DNA fragmentation in kidney tissues, and altered renal histoarchitecture. The co-administration of Se and/or ZnCl2 has exhibited pronounced chelative, antioxidant, and genoprotective effects against K2Cr2O7-induced renal damage and attenuated partially the histopathological alterations. These results suggest that Se and Zn can be used as efficient nephroprotective agents against K2Cr2O7-induced toxicity in pregnant Wistar Albino rats.

Contact Dermatitis in Construction Workers in Northeastern Italian Patch Test Database Between 1996 and 2016.

BACKGROUND: Contact dermatitis in construction workers (CWs) is frequent due to the widespread exposure to sensitizing substances and irritating agents and the wet and cold working conditions. OBJECTIVE: Our objectives were to evaluate contact dermatitis characteristics among CWs who underwent patch test in northeastern Italy and to identify related allergens. METHODS: Seven hundred ninety-five CWs were studied and their data were compared to 2.099 male white-collar workers. The associations between patch test results and occupations were assessed by multivariate logistic regression analysis. Incidence data were calculated from 1996 to 2016. RESULTS: CWs with confirmed occupational dermatitis presented an increased risk to be sensitized to potassium dichromate [OR 3.1 (95%IC 2.0-4.8)], to thiurams [OR 8 .6 (95%IC 4.0-18.4)], and to epoxy resins [OR 12.7 (95%IC 6.1-26.4)]. Sensitization to chromate decreased significantly after 2004, following EU regulation of chromate content in concrete, while sensitization to epoxy resins and thiurams increased. The overall incidence of occupational contact dermatitis in CWs decreased significantly. CONCLUSION: Our study demonstrated the effectiveness of EU regulations in reducing chromate sensitization in CWs and the overall incidence of occupational contact dermatitis. However, sensitization to other haptens is increasing, though improvement of protective measures is compulsory.

L-carnitine and Co Q10 ameliorate potassium dichromate -induced acute brain injury in rats targeting AMPK/AKT/NF-κß.

Adenosine monophosphate-activated protein kinase (AMPK) has a crucial role in neuroprotection. It phosphorylates serine/threonine kinase (Akt) Substrate inhibiting the inflammatory responses induced by the nuclear factor-κB (NF-κB). Exposure to chromium VI dust among workers has been reported and induced brain injury, as the absorption of chromium through the nasal membrane has been found to deliver it directly to the brain. The study aimed to investigate the influence of administration of L-carnitine or/and Co Q10 as theraputic agents against potassium dichromate (PD)-induced brain injury via AMPK/AKT/NF-κß signaling pathway. Brain injury was induced by PD intranasally as a single dose of 2 mg/kg, 24 h latter rats received L-carnitine (100 mg/kg; orally), Co Q10 (50 mg/kg; orally) and L-carnitine (50 mg/kg; orally) + Co Q10 (25 mg/kg; orally) respectively for 3 days. Locomotor activity was assessed before and at the end of the experiment, then, biochemical and histopathological investigations were assessed in brain homogenate. The exposure of rats to PD promoted oxidative stress and inflammation via an increase in MDA and a decrease in GSH brain contents with an increase in brain contents of TNF-α, IL-6, and NF-kß and reduced AMPK and AKT brain contents as compared to the control group. Treatment with L-carnitine + Co Q10 ameliorated cognitive impairment and oxidative stress, decreased the brain contents of inflammatory mediators; TNF-α, IL-6, and NF-κß elevated AMPK and AKT, as compared to each drug. Also, L-carnitine + Co Q10 administration restored morphological changes as degenerated neurons and necrosis. L-carnitine + Co Q10 play important role in AMPK/AKT/NF-κß pathway that responsible for their antioxidant and anti-inflammatory effects against PD-induced brain injury in rats.