La maladie de l’oreille du surfeur : l’imaginaire du soi naturalisé à partir d’une pathologie due à l’immersion en milieu aquatique

GoalsStarting from the example of the exostosis of the external auditory canal, a modification due to the impact of the sea on the body, this article considers how this pathology is experienced and interpreted by those who contract it. After defining “surfer's ear” from an anthropo-medical point of view, we will address the meaning that individuals give to it, such as the belief of becoming fish.MethodologyOver the course of several years of field observation and interviews, mainly on the beaches of the Atlantic Pyrenees, we were able to compare different individuals’ discourses about how the surfing body, immersed in nature, is perceived and experienced.ResultsThis helps to understand thoughts that can link people to the ocean, and more widely to nature, in our contemporary Western society. Thus, penetrating and being penetrated by this living water implies a sensual relationship with the environment, in a search both for erotic pleasure and an enveloping maternal security, lost from birth.DiscussionThis relationship to the environment implements a sensory ecology where the human becomes nature, and nature takes human form. This is an occasion for the reinvention of links, not in an opposition between human and non-human, but by reminding humans that they can find balance in abandoning themselves to nature.ConclusionPathologies of the ear define an imaginary clinic of the body. The body is thus rendered unfit by the physical sensations of marine pathology but, above all, by the belief in a psychic envelopment in water.     

Purification and characterization of the carbonic anhydrase enzyme from Black Sea trout (Salmo trutta Labrax Coruhensis) kidney and inhibition effects of some metal ions on enzyme activity

In this study, the carbonic anhydrase (CA) enzyme was purified from Black Sea trout (Salmo trutta Labrax Coruhensis) kidney with a specific activity of 603.77 EU/mg and a yield of 35.5% using Sepharose-4B-l-tyrosine- sulphanilamide affinity column chromatography. For determining the enzyme purity and subunit molecular mass, sodiumdodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) was performed and single band was observed. The molecular mass of subunit was found approximately 29.71 kDa. The optimum temperature, activation energy (E_a), activation enthalpy (ΔH) and Q₁₀ values were obtained from Arrhenius plot. K_m and V_max values for p-nitrophenyl acetate of the purified enzyme were calculated from Lineweaver-Burk graphs. In addition, the inhibitory effects of different heavy metal ions (Fe²⁺, Pb²⁺, Co²⁺, Ag⁺ and Cu²⁺) on Black Sea trout kidney tissue CA enzyme activities were investigated by using esterase method under in vitro conditions. The heavy metal concentrations inhibiting 50% of enzyme activity (IC₅₀) were obtained. Finally K_i values and inhibition types were calculated from Lineweaver-Burk graphs.     

Amino-functionalized mesoporous silica nanoparticles (NH2-MSiNPs) impair the embryonic development of the sea urchin Paracentrotus lividus

Nanoparticles have found use in a wide range of applications, mainly as carriers of active biomolecules. It is thus necessary to assess their toxicity for human health, as well as for the environment, on which there is still a gap of knowledge. In this work, sea urchin Paracentrotus lividus, a widely used model for embryotoxicity and spermiotoxicity, has been used to assess potential detrimental effects of amino-functionalized mesoporous silica nanoparticles (NH₂-MSiNPs) on embryonic development. Specifically, gametes quality, embryogenesis morphological and timing alterations, and cellular stress markers, such as mitochondrial functionality, were assessed in presence of different concentrations of NH₂-MSiNPs in filtered seawater (FSW). Furthermore, dorsal-ventral axis development and skeletogenesis were characterized by microscopy imaging and gene expression analysis. NH₂-MSiNPs determined a strong reduction in the egg fertilization rate. Consequently, the presence of NH₂-MSiNPs resulted detrimental in P. lividus embryonic development, with severe morphological alterations correlated with an increased embryos mortality. Finally, NH₂-MSiNPs treatment was responsible for other toxic effects, such as reduced mitochondrial function and skeletogenesis alterations, according to the reduced mineralization sites in the endoskeleton formation and the related genes altered expression. Taken together, these results suggest the potential toxic effects of NH₂-MSiNPs on the marine ecosystem, with consequences for the development and reproduction of its organisms. Despite their promising potential as carriers of biomolecules, it is pivotal to consider that their uncontrolled use may result harmful to the environment and, consequently, to living organisms.     

沙棘提取物促进大鼠肛周脓肿术后创面愈合效果及对 p38/MK2通路的影响

目的 探讨沙棘提取物对大鼠肛周脓肿术后创面愈合及p38/丝裂原活化蛋白激酶2(MK2)通路的影响。方法 2021年6—12月,选取SD大鼠60只,采用随机数表法分成假手术组、模型组、阳性对照组（左氧氟沙星,63 mg/kg）、沙棘提取物低（5 g/kg）、中（10 g/kg）、高（20 g/kg）剂量组,每组10只。构建肛周脓肿术后大鼠模型,测量大鼠术后0 d和观察期（7 d和14 d）的创面大小,计算创面愈合率;采用ELISA法检测大鼠血清中肿瘤坏死因子-α(TNF-α)、白细胞介素（IL）-1β和IL-6水平;观察大鼠创面组织病理改变;应用实时荧光定量PCR(RT-qPCR)法检测大鼠创面组织p38、MK2mRNA,蛋白质印迹法检测大鼠创面组织p38、MK2蛋白。结果 模型组大鼠创面组织表皮厚度最薄,细胞边界模糊,细胞排列紊乱,阳性对照组和沙棘提取物各剂量组表皮厚度明显增加,且随着沙棘提取物剂量的增加表皮厚度逐渐增厚。与假手术组比较,创面组织p38、MK2 mRNA(1.00±0.02比1.82±0.12,1.00±0.03比1.70±0.14)和创面组织p38、MK2蛋白（0.6...     

The potential health impacts of climate change: An overview

Climate change would have a range of impacts on human health. Health impacts would be caused by the direct effect of climatic factors on human health, such as heat stress, and possible changes in the frequency and intensity of extreme weather events such as storms, floods and droughts. Impacts on health would also be mediated by the indirect effects of climate change, such as changes in availability of food and water and the distribution of vector‐borne diseases. The majority of health impacts would be adverse and would depend greatly on the vulnerability of populations.     

Bio-accumulation and health risk assessment of heavy metals in different edible fish species from Hurghada City,Red Sea,Egypt

BackgroundHeavy metal contamination has become a serious issue in this century especially detected in fish organs. Due to the presence of radioactive compounds in agricultural and sewage effluent, which destroys aquatic ecosystems, threatening human livelihoods. Health hazards associated with low and high consumption consumers assessed in five commercial fish species collected from Hurghada City, Egypt, during winter and summer, 2020. Atomic absorption spectrophotometer technique used for determination heavy meals in different organs and expressed as μg/g wet weight.ResultsHeavy metal concentrations in muscle ranged between:(0.054–0.109), (0.260–1.043), (0.264–0.897), (5.895–11.898), (0.381–0.970), (13.582–29.133) and (0.332–0.589) µg/g for Cd, Pb, Mn, Zn, Cu, Fe and Ni respectively, which were lower than those of gills and liver. These concentrations were within WHO, FAO/WHO, and EU standards. Consumption of edible species was lower than the (TDIs) established by the (JECFA) and Egyptian Standards. Even though THQ and TTHQ values were < 1 while, in children with highly consumer were> 1.ConclusionThis study concluded that intake of Red Sea fish is safe for human health. It is critical for consumers to be aware of the consequences of excessive fish consumption, particularly children with highly consumer, which represent possible health risks.     

Cell mediated immune response of the Mediterranean sea urchin Paracentrotus lividus after PAMPs stimulation

The Mediterranean sea urchin (Paracentrotus lividus) is of great ecological and economic importance for the European aquaculture. Yet, most of the studies regarding echinoderm's immunological defense mechanisms reported so far have used the sea urchin Strongylocentrotus purpuratus as a model, and information on the immunological defense mechanisms of Paracentrotus lividus and other sea urchins, is scarce. To remedy this gap in information, in this study, flow cytometry was used to evaluate several cellular immune mechanisms, such as phagocytosis, cell cooperation, and ROS production in P. lividus coelomocytes after PAMP stimulation. Two cell populations were described. Of the two, the amoeboid-phagocytes were responsible for the phagocytosis and ROS production. Cooperation between amoeboid-phagocytes and non-adherent cells resulted in an increased phagocytic response. Stimulation with several PAMPs modified the phagocytic activity and the production of ROS. The premise that the coelomocytes were activated by the bacterial components was confirmed by the expression levels of two cell mediated immune genes: LPS-Induced TNF-alpha Factor (LITAF) and macrophage migration inhibitory factor (MIF). These results have helped us understand the cellular immune mechanisms in P. lividus and their modulation after PAMP stimulation.     

Role for urea in nitrification by polar marine Archaea

Despite the high abundance of Archaea in the global ocean, their metabolism and biogeochemical roles remain largely unresolved. We investigated the population dynamics and metabolic activity of Thaumarchaeota in polar environments, where these microorganisms are particularly abundant and exhibit seasonal growth. Thaumarchaeota were more abundant in deep Arctic and Antarctic waters and grew throughout the winter at surface and deeper Arctic halocline waters. However, in situ single-cell activity measurements revealed a low activity of this group in the uptake of both leucine and bicarbonate (<5% Thaumarchaeota cells active), which is inconsistent with known heterotrophic and autotrophic thaumarchaeal lifestyles. These results suggested the existence of alternative sources of carbon and energy. Our analysis of an environmental metagenome from the Arctic winter revealed that Thaumarchaeota had pathways for ammonia oxidation and, unexpectedly, an abundance of genes involved in urea transport and degradation. Quantitative PCR analysis confirmed that most polar Thaumarchaeota had the potential to oxidize ammonia, and a large fraction of them had urease genes, enabling the use of urea to fuel nitrification. Thaumarchaeota from Arctic deep waters had a higher abundance of urease genes than those near the surface suggesting genetic differences between closely related archaeal populations. In situ measurements of urea uptake and concentration in Arctic waters showed that small-sized prokaryotes incorporated the carbon from urea, and the availability of urea was often higher than that of ammonium. Therefore, the degradation of urea may be a relevant pathway for Thaumarchaeota and other microorganisms exposed to the low-energy conditions of dark polar waters.     

游泳池肉芽肿5例分析

报告5例游泳池肉芽肿,患者均有水源性接触史,皮损特点均为暗红色丘疹、结节,沿淋巴管扩散。组织病理示肉芽肿性炎,但微生物学感染证据常缺乏。治疗药物选用利福平、乙胺丁醇和克拉霉素。该文对患者临床表现、实验室检查及预后做出分析,并对微生物学感染证据的相关情况展开讨论,总结游泳池肉芽肿的诊断要点,即通过鱼或水源接触史、临床表现、组织病理及病原体查找确诊。