RESUMEN
Global climate change intensifies the water cycle and makes freshest waters become fresher and vice-versa. But how this change impacts phytoplankton in coastal, particularly harmful algal blooms (HABs), remains poorly understood. Here, we monitored a coastal bay for a decade and found a significant correlation between salinity decline and the increase of Karenia mikimotoi blooms. To examine the physiological linkage between salinity decreases and K. mikimotoi blooms, we compare chemical, physiological and multi-omic profiles of this species in laboratory cultures under high (33) and low (25) salinities. Under low salinity, photosynthetic efficiency and capacity as well as growth rate and cellular protein content were significantly higher than that under high salinity. More strikingly, the omics data show that low salinity activated the glyoxylate shunt to bypass the decarboxylation reaction in the tricarboxylic acid cycle, hence redirecting carbon from CO2 release to biosynthesis. Furthermore, the enhanced glyoxylate cycle could promote hydrogen peroxide metabolism, consistent with the detected decrease in reactive oxygen species. These findings suggest that salinity declines can reprogram metabolism to enhance cell proliferation, thus promoting bloom formation in HAB species like K. mikimotoi, which has important ecological implications for future climate-driven salinity declines in the coastal ocean with respect to HAB outbreaks.
Asunto(s)
Cambio Climático , Floraciones de Algas Nocivas , Salinidad , Fotosíntesis , Fitoplancton/crecimiento & desarrollo , Fitoplancton/fisiología , Carbono/metabolismo , Carbono/análisisRESUMEN
Background: Kimura disease (KD) is a rare chronic inflammatory disease that affects mainly young Asian men and is characterized by painless subcutaneous masses, lymphadenopathy, and elevated serum IgE levels. Despite its benign nature, KD poses a diagnostic and therapeutic challenge due to its rarity and clinical variability. Objective: This study aimed to provide a comprehensive analysis of the clinical and radiological features of KD in a retrospective case series, to assess treatment outcomes, and to discuss the implications for diagnosis and management. Methods: We retrospectively analyzed four histologically confirmed cases of KD admitted to Zhejiang Provincial People's Hospital from January 2018 to October 2023. Clinical and radiological data were retrospectively analyzed, and imaging findings were analyzed by two neuroradiologists to determine lesion characteristics and contrast enhancement patterns. Results: Our findings showed that the patients were predominantly male, with a mean age of 43 years and an age range of 13-71 years. All patients presented with painless subcutaneous masses and three of them had peripheral blood eosinophilia and elevated serum IgE levels. Radiographically, the lesions were predominantly ill-defined with heterogeneous enhancement, accompanied by subcutaneous fat atrophy. Complete surgical excision and oral corticosteroids were effective treatments, and no recurrence was noted during follow-up. Conclusion: KD should be considered in the differential diagnosis of painless subcutaneous masses in the head and neck region, especially in the presence of eosinophilia and elevated IgE levels. Our findings contribute to the understanding of KD's clinical and radiological spectrum and highlight the need for long-term follow-up due to the risk of recurrence.
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ε-Caprolactone is an important non-toxic compound for polymer synthesis like polycaprolactone which has been widely used in drug delivery and degradable plastics. To meet the demand for a green economy, a bi-enzymatic cascade, consisting of an alcohol dehydrogenase (ADH) and a cyclohexanone monooxygenase (CHMO), was designed and introduced into Escherichia coli to synthesize ε-caprolactone from cyclohexanol with a self-sufficient NADPH-cofactor regeneration system. To further improve the catalytic efficiency, a carbonyl group-dependent colorimetric method using inexpensive 2,4-dinitrophenylhydrazine (DNPH) was developed for assay of cyclohexanone, an intermediate production of cascade reaction. It can be used to screen mutant strains with high catalytic efficiency from high-throughput library by detecting the absorbance value in microtiter plates (MTP) instead of gas chromatography (GC) analysis. Moreover, an RBS combinatorial library was constructed for balancing the expression of ADH and CHMO from two independent transcriptional units. After the high-throughput screening based on intermediate product control, an optimal variant with higher substrate tolerance and long-term stability was obtained from RBS combinatorial library. Through a fed-batch process, ε-caprolactone production reached 148.2 mM after 70 h of reaction under the optimized conditions, which was the highest yield achieved to date.
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Escherichia coli , Oxigenasas , Escherichia coli/genética , Escherichia coli/metabolismo , Caproatos/química , Lactonas/química , Alcohol Deshidrogenasa/metabolismoRESUMEN
ABSTRACT Macamides and Macaenes are the bioactive marker compounds in maca (Lepidium meyenii Walp., Brassicaceae) tuber. To simultaneously quantify these two types of compound, HPLC method was studied. To distinguish and group the growing regions of different maca samples, Hierarchical cluster analysis, a chemometric method, was applied to analyze the HPLC data. The calibration curves obtained using the HPLC method showed satisfactory linearity with determination coefficients >0.9998. The precision and repeatability relative standard deviation values were <4%, and the accuracy relative standard deviation value was <5%. The limits of detection was <0.1 µg/ml and the limit of quantification was <0.3 µg/ml. Our HPLC method was successfully used for the separation and determination of macamides and macaenes in Maca within 45 min, i.e., two macaenes (9-oxo-10E,12Z-octadecadienoic acid and 9-oxo-10E,12E-octadecadienoic acid) and five macamides (N-benzyl-9-oxo-10E,12Z-octadecadienamide, N-benzyl-9-oxo-10E,12E-octadecadienamide, N-benzyl-9Z,12Z,15Z-octadecatrienamide, N-benzyl-9Z,12Z-octadecadienamide and N-benzyl-hexadecanamide). The HPLC method was applied to analyze and quantify the seven compounds in thirty maca samples with different colors and origins. The origins of all the maca samples were distinguished and grouped using hierarchical cluster analysis of the HPLC data. Accordingly, the metabolism of macaenes and macamides in maca post-harvest processing has also been proposed. The HPLC method is efficient to simultaneously quantify the macamides and macaenes in maca. Analyzing the HPLC data using hierarchical cluster analysis can distinguish maca growing origins.