Can the toxicity of polyethylene microplastics and engineered nanoclays on flatfish (Solea senegalensis) be influenced by the presence of each other?

Microplastics and nanomaterials are applied in a myriad of commercial and industrial applications. When leaked to natural environments, such small particles might threaten living organisms' health, particularly when considering their potential combination that remains poorly investigated. This study investigated the physiological and biochemical effects of polyethylene (PE; 64-125 µm in size, 0.1, 1.0, and 10.0 mg·L-1) single and combined with an engineered nanomaterial applied in antifouling coatings, the copper-aluminium layered double hydroxides (Cu-Al LDH; 0.33, 1.0, and 3.33 mg·L-1) in the flatfish Solea senegalensis larvae (8 dph) after 3 h exposure, in a full factorial design. Particles ingestion, histopathology, and biochemical biomarkers were assessed. Fish larvae presented <1 PE particles in their gut, independently of their concentration in the medium. The histological health index showed minimal pathological alterations at PE combined exposure, with a higher value observed at 1 mg LDH·L-1 × 0.1 mg PE·L-1. Gut deformity and increased antioxidant defences (catalase), neurotransmission (acetylcholinesterase), and aerobic energy production (electron transport system) were observed at PE ≥ 1.0 mg·L-1. No oxidative damage (lipid peroxidation) or alterations in the detoxification capacity (glutathione-S-transferase) was observed on single and combined exposures. PE, combined or not with Cu-Al LDH, does not seem to compromise larvae's homeostasis considering levels reported so far in the marine and aquaculture environments. However, harsh effects are expected with MP contamination rise, as projections suggest.

Knee osteoarthrosis secondary to ochronosis -clinical case / Osteoartrose do joelho secundária a ocronose -Caso clínico

Alkaptonuria is a rare metabolic disease in which a deficiency of the enzyme homogentisate dioxygenase causes an accumulation of homogentisic acid. Ochronosis consists of excessive deposition of homogentisic acid in the connective tissue and presents as a chestnut brown or black pigmentation. With aging, the accumulation of pigments from homogentisic acid in the joints causes osteoarthrosis. There is no specific treatment for the disease and the approach is symptomatic. Arthroplasty is the solution for severe cases of osteoarthrosis caused by this pathological condition and presents results comparable to those from patients with primary osteoarthrosis. Here, the case of a 67-year-old patient who underwent several arthroplasty procedures because of osteoarthrosis caused by this rare pathological condition is presented. The last surgical intervention consisted of total right knee arthroplasty...

A alcaptonúria é uma doença metabólica rara em que a deficiência da enzima ácido homogentísico-oxidase provoca uma acumulação de ácido homogentísico. A ocronose consiste na deposição excessiva de ácido homogentísico no tecido conjuntivo e apresenta-se como uma pigmentação acastanhada ou preta. Com o envelhecimento, a acumulação de pigmentos de ácido homogentísico nas articulações provoca osteoartrose. Não existe um tratamento específico para a doença e a abordagem é sintomática. A artroplastia é a solução para casos graves de osteoartrose causada poressa patologia e apresenta resultados compa-ráveis aos doentes com osteoartrose primária. Os autores apresentam o caso de um doente de 67 anos submetido a várias artroplastias, em virtude da osteoartrose causada por essa rara patologia. A última intervenção cirúrgica foi uma artroplastia total do joelho direito...

Knee osteoarthrosis secondary to ochronosis - clinical case.

Alkaptonuria is a rare metabolic disease in which a deficiency of the enzyme homogentisate dioxygenase causes an accumulation of homogentisic acid. Ochronosis consists of excessive deposition of homogentisic acid in the connective tissue and presents as a chestnut brown or black pigmentation. With aging, the accumulation of pigments from homogentisic acid in the joints causes osteoarthrosis. There is no specific treatment for the disease and the approach is symptomatic. Arthroplasty is the solution for severe cases of osteoarthrosis caused by this pathological condition and presents results comparable to those from patients with primary osteoarthrosis. Here, the case of a 67-year-old patient who underwent several arthroplasty procedures because of osteoarthrosis caused by this rare pathological condition is presented. The last surgical intervention consisted of total right knee arthroplasty.

A alcaptonúria é uma doença metabólica rara em que a deficiência da enzima ácido homogentísico-oxidase provoca uma acumulação de ácido homogentísico. A ocronose consiste na deposição excessiva de ácido homogentísico no tecido conjuntivo e apresenta-se como uma pigmentação acastanhada ou preta. Com o envelhecimento, a acumulação de pigmentos de ácido homogentísico nas articulações provoca osteoartrose. Não existe um tratamento específico para a doença e a abordagem é sintomática. A artroplastia é a solução para casos graves de osteoartrose causada por essa patologia e apresenta resultados comparáveis aos doentes com osteoartrose primária. Os autores apresentam o caso de um doente de 67 anos submetido a várias artroplastias, em virtude da osteoartrose causada por essa rara patologia. A última intervenção cirúrgica foi uma artroplastia total do joelho direito.