Macropinocytosis in Gracilariopsis lemaneiformis (Rhodophyta)

Macropinocytosis is an endocytic process that plays an important role in animal development and disease occurrence but until now has been rarely reported in organisms with cell walls. We investigated the properties of endocytosis in a red alga, Gracilariopsis lemaneiformis. The cells non-selectively internalized extracellular fluid into large-scale endocytic vesicles (1.94 ± 0.51 μm), and this process could be inhibited by 5-(N-ethyl-N-isopropyl) amiloride, an macropinocytosis inhibitor. Moreover, endocytosis was driven by F-actin, which promotes formation of ruffles and cups from the cell surface and facilitates formation of endocytotic vesicles. After vesicle formation, endocytic vesicles could be acidified and acquire digestive function. These results indicated macropinocytosis in G. lemaneiformis. Abundant phosphatidylinositol kinase and small GTPase encoding genes were found in the genome of this alga, while PI3K, Ras, and Rab5, the important participators of traditional macropinocytosis, seem to be lacked. Such findings provide a new insight into endocytosis in organisms with cell walls and facilitate further research into the core regulatory mechanisms and evolution of macropinocytosis

Association Between Cerebral Hypoperfusion and Cognitive Impairment in Patients With Chronic Vertebra-Basilar Stenosis

Objective: This study aimed to investigate the association between cognitive impairment and cerebral haemodynamic changes in patients with chronic vertebra-basilar (VB) stenosis.Methods: Patients with severe posterior circulation VB stenosis and infarction or a history of infarction for more than 2 weeks from January 2014 to January 2015 were enrolled (n = 96). They were divided into three groups, namely, the computed tomography perfusion (CTP) normal group, the CTP compensated group, and the CTP decompensated group. Cognitive function was assessed using a validated Chinese version of the Mini-Mental State Examination (MMSE), the Frontal Assessment Battery (FAB), and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Regression models were used to identify independent risk factors for cognitive impairment.Results: The MMSE and FAB scores of patients in the CTP decompensated group were significantly lower than those of patients in the CTP normal and CTP compensated groups (all p < 0.05). The RBANS total and its domain scores, including immediate memory, visual acuity, and delayed memory, in the CTP compensated and CTP decompensated groups were significantly lower than those in the CTP normal group (all p < 0.05). Multiple regression analyses showed that CTP compensation, CTP decompensation, severe VB tandem stenosis, and multiple infarctions were independent risk factors for cognitive impairment.Conclusions: Low perfusion caused by severe VB stenosis can lead to extensive cognitive impairments in areas such as immediate memory, visual span, and delayed memory

Direct Z‑Scheme In₂O₃/In₂S₃ Heterojunction for Oxygen-Mediated Photocatalytic Hydrogen Production

We demonstrate the viability of the In2O3/In2S3 heterojunction for efficient photocatalytic H2 evolution from a formaldehyde aqueous solution, which is an alternative renewable hydrogen source, in a direct Z-scheme manner under visible light without any electron mediator and cocatalyst. The optimal In2O3/In2S3 heterojunction shows a fast hydrogen evolution rate of 6.16 mmol·g–1·h–1, which is approximately 166 times and 6 times higher than that of pure In2O3 and pure In2S3, respectively. The superior photocatalytic activity of the In2O3/In2S3 heterojunction compared to single-component In2O3 and In2S3 is attributed to its appropriate band gap, enhanced charge separation, and transfer abilities, as attested by various spectroscopic characterization and photoelectrochemistry experiments. Among the different fabrication approaches, the sequential hydrothermal–calcination technique, which produces a hydrangea-like morphology, affords the most active In2O3/In2S3 heterojunction photocatalyst. Molecular O2 is found to play a key role in instigating the photocatalytic H2 evolution from formaldehyde oxidation as a catalytic electron scavenger, which is not consumed throughout the reaction

Carbon-catalyzed oxygen-mediated dehydrogenation of formaldehyde in alkaline solution for efficient hydrogen production

We report an efficient process to dehydrogenate formaldehyde in alkaline solution, catalyzed by carbon nanotubes (CNTs) via a unique reaction mechanism involving molecular O2. The superior catalytic performance of carbon nanotubes (CNTs) compared to the other carbon-based catalysts is attributed to their sp2-carbon-rich surface, hydrophilicity and abundant surface defects, which are the most plausible active sites. Peroxide species originating from the activation of adsorbed molecular oxygen on the CNTs is found to be a key to C–H activation, leading to efficient hydrogen production. The cost-effective carbon-based dehydrogenation catalysts offer new opportunities to the development of novel liquid organic hydrogen carrier technologies.National Research Foundation (NRF)Submitted/Accepted versionThe authors are grateful for financial supports from the National Natural Science Foundation of China (No. 21872123 and 22172143). H.L.Tan and W.Liu acknowledge funding from National Research Foundation of Singapore under its Campus for Research Excellence and Technological Enterprise (CREATE) programme

Sesquiterpene-neolignans from <i>Manglietia hookeri</i>

<p>The comet assay-guided fractionation of the twigs of <i>Manglietia hookeri</i> resulted in the isolation of three sesquiterpene-neolignans, including a new one 5-allyl-2-(4-allyl-phenoxy)-3-[7-(1-hydroxy-1-methyl-ethyl)-1, 4a-dimethyl-decahydro-naphthalen-1-yloxy]-phenol (<b>1</b>), and eudesobovatol A (<b>2</b>) and eudesobovatol B (<b>3</b>), together with three lignans, obovatol (<b>4</b>), honokiol (<b>5</b>) and magnolol (<b>6</b>). Their structures were elucidated on the basis of spectral analysis and by comparison with related literature data. Compounds <b>1</b>, <b>4</b>–<b>6</b> showed a protective effect on UV inductive DNA damage in mice lymphocyte cells, while compound <b>1</b> indicated the smallest Olive Tail Moment 7.34 ± 2.09 at 6 × 10⁻⁶ μM.</p

Table_1_Macropinocytosis in Gracilariopsis lemaneiformis (Rhodophyta).xlsx

Macropinocytosis is an endocytic process that plays an important role in animal development and disease occurrence but until now has been rarely reported in organisms with cell walls. We investigated the properties of endocytosis in a red alga, Gracilariopsis lemaneiformis. The cells non-selectively internalized extracellular fluid into large-scale endocytic vesicles (1.94 ± 0.51 μm), and this process could be inhibited by 5-(N-ethyl-N-isopropyl) amiloride, an macropinocytosis inhibitor. Moreover, endocytosis was driven by F-actin, which promotes formation of ruffles and cups from the cell surface and facilitates formation of endocytotic vesicles. After vesicle formation, endocytic vesicles could be acidified and acquire digestive function. These results indicated macropinocytosis in G. lemaneiformis. Abundant phosphatidylinositol kinase and small GTPase encoding genes were found in the genome of this alga, while PI3K, Ras, and Rab5, the important participators of traditional macropinocytosis, seem to be lacked. Such findings provide a new insight into endocytosis in organisms with cell walls and facilitate further research into the core regulatory mechanisms and evolution of macropinocytosis.</p

DataSheet_1_Macropinocytosis in Gracilariopsis lemaneiformis (Rhodophyta).pdf

Macropinocytosis is an endocytic process that plays an important role in animal development and disease occurrence but until now has been rarely reported in organisms with cell walls. We investigated the properties of endocytosis in a red alga, Gracilariopsis lemaneiformis. The cells non-selectively internalized extracellular fluid into large-scale endocytic vesicles (1.94 ± 0.51 μm), and this process could be inhibited by 5-(N-ethyl-N-isopropyl) amiloride, an macropinocytosis inhibitor. Moreover, endocytosis was driven by F-actin, which promotes formation of ruffles and cups from the cell surface and facilitates formation of endocytotic vesicles. After vesicle formation, endocytic vesicles could be acidified and acquire digestive function. These results indicated macropinocytosis in G. lemaneiformis. Abundant phosphatidylinositol kinase and small GTPase encoding genes were found in the genome of this alga, while PI3K, Ras, and Rab5, the important participators of traditional macropinocytosis, seem to be lacked. Such findings provide a new insight into endocytosis in organisms with cell walls and facilitate further research into the core regulatory mechanisms and evolution of macropinocytosis.</p