Pulse Feature-Enhanced Classification of Microalgae and Cyanobacteria Using Polarized Light Scattering and Fluorescence Signals.

Harmful algal blooms (HABs) pose a global threat to the biodiversity and stability of local aquatic ecosystems. Rapid and accurate classification of microalgae and cyanobacteria in water is increasingly desired for monitoring complex water environments. In this paper, we propose a pulse feature-enhanced classification (PFEC) method as a potential solution. Equipped with a rapid measurement prototype that simultaneously detects polarized light scattering and fluorescence signals of individual particles, PFEC allows for the extraction of 38 pulse features to improve the classification accuracy of microalgae, cyanobacteria, and other suspended particulate matter (SPM) to 89.03%. Compared with microscopic observation, PFEC reveals three phyla proportions in aquaculture samples with an average error of less than 14%. In this paper, PFEC is found to be more accurate than the pulse-average classification method, which is interpreted as pulse features carrying more detailed information about particles. The high consistency of the dominant and common species between PFEC and microscopy in all field samples also demonstrates the flexibility and robustness of the former. Moreover, the high Pearson correlation coefficient accounting for 0.958 between the cyanobacterial proportion obtained by PFEC and the cyanobacterial density given by microscopy implies that PFEC serves as a promising early warning tool for cyanobacterial blooms. The results of this work suggest that PFEC holds great potential for the rapid and accurate classification of microalgae and cyanobacteria in aquatic environment monitoring.

Thorectidiol A Isolated from the Marine Sponge Dactylospongia elegans Disrupts Interactions of the SARS-CoV-2 Spike Receptor Binding Domain with the Host ACE2 Receptor.

Thorectidiols isolated from the marine sponge Dactylospongia elegans (family Thorectidae, order Dictyoceratida) collected in Papua New Guinea are a family of symmetrical and unsymmetrical dimeric biphenyl meroterpenoid stereoisomers presumed to be products of oxidative phenol coupling of a co-occurring racemic monomer, thorectidol (3). One member of the family, thorectidiol A (1), has been isolated in its natural form, and its structure has been elucidated by analysis of NMR, MS, and ECD data. Acetylation of the sponge extract facilitated isolation of additional thorectidiol diacetate stereoisomers and the isolation of the racemic monomer thorectidol acetate (6). Racemic thorectidiol A (1) showed selective inhibition of the SARS-CoV-2 spike receptor binding domain (RBD) interaction with the host ACE2 receptor with an IC50 = 1.0 ± 0.7 µM.

Three new indole diterpenoids from Aspergillus aculeatus KKU-CT2.

Three new indole diterpenoids, aculeatupenes A-C (1-3), together with four known compounds (4-7), were isolated from the mycelium of Aspergillus aculeatus KKU-CT2. Their structures were established by spectroscopic evidence and absolute configurations of 1-3 were determined by comparison of their experimental and calculated ECD spectra. Compounds 1, 2, and emindole SB (4) showed weak cytotoxicity against HelaS3, KB, HepG2, MCF-7, and A549 cancer cell lines with IC50 values in the range of 11.12-67.81 µM. Compound 3 showed weak cytotoxicity against HelaS3 cell lines with an IC50 value of 17.48 µM but non-cytotoxicity against Vero cell line. In addition, compound 1 exhibited weak antibacterial activity against Bacillus cereus.[Formula: see text].

How Long Can A C-C σ-Single Bond Be?

In a specifically designed molecular structure, two sp2-hybridized carbon atoms align their unhybridized 2pz orbitals in the same orientation to form an extremely long C2pz-C2pz σ-single bond that goes beyond 3 Å in length. This new type of C-C σ-bond (coined as a fringe bond) can be made more than 1 Å longer than the current experimental world record (∼1.8 Å) and 300 kJ/mol weaker than the ordinary C-C σ-bond (∼330 kJ/mol). If such molecular monomers are polymerized into infinite chains, the extended long C-C saturated σ-bonding framework manifests band gaps similar to those of some conventional iconic organic-conducting polymers based on conjugated networks of unsaturated bonds.

Phloroglucinol Benzophenones and Xanthones from the Leaves of Garcinia cowa and Their Nitric Oxide Production and α-Glucosidase Inhibitory Activities.

Five new compounds-two phloroglucinol benzophenones, garciniacowones F (1) and G (2), and three xanthones, garciniacowones H (3), I (4), and J (5)-together with seven known xanthones (6-12) were isolated from the fresh leaves of Garcinia cowa. Their structures were elucidated by detailed analysis of NMR and MS data. Compounds 1 and 2 are phloroglucinol benzophenones containing a polyprenylated bicyclo[3.3.1]nonane ring system, while compounds 3-5 are rare xanthones having farnesyl (3 and 5) and geranylgeranyl (5) units at C-8. Compounds 1, 3, 4, 7, 8, and 10 exhibited inhibitory effects on NO production in LPS-induced RAW264.7 macrophage cells with IC50 values ranging from 5.4 to 18.6 µM. Compounds 4 and 8 had α-glucosidase inhibitory activities with IC50 values of 15.4 and 11.4 µM, respectively, which were more potent than that of the acarbose control.

[Genetic diversity and volatile components of Asarum sieboldii in Qin-ba region].

OBJECTIVE: To analyze the genetic diversity and the volatile components of Asarum sieboldii from seven habitats in Qin-ba region. METHODS: The genetic diversity of the herb was analyzed by ISSR (inter simple sequence repeat) markers; The relative content volatile components of the herb were dectected by head space solid-phase microextraction gas chromatogrphy-mass spectrometry (HS-SPME-GC-MS). The contents of the 3 main components were analyzed by steam distillation gas chromatography-mass spectrometry (GC-MS). RESULTS: 57 bands were amplified from 7 populations by 6 reliable primers, 51 of which were polymorphic (89.47% of the total). The cluster analysis presented that these resources were divided into two main groups. There were differences in the chemical components and the contents of Asarum sieboldii from the 6 wild habitats. Except for some same components, many unique components were identified in them respectively. In addition, some components could be detected only in some populations which had smaller genetic distance. CONCLUSION: Cluster analysis shows no direct correlation between genetic distance and geographic distance of Asarum sieboldii in Qin-ba region. The accumulations of some volatile components of Asarum sieboldii are possibly related to genetic diversity.

Cardioprotective effect of SMND-309, a novel derivate of salvianolic acid B on acute myocardial infarction in rats.

(2E)-2-{6-[(E)-2-carboxyvinyl]-2,3-dihydroxyphenyl}-3-(3,4-dihydroxyphenyl) propenoic acid, a novel compound designated SMND-309, is a new derivate of salvianolic acid B. The present study was designed to investigate the cardioprotective potential of SMND-309 and to elucidate the possible mechanisms on the basis of biochemical, histopathological and immunohistochemical studies in a rat model of acute myocardial infarction induced by permanent ligation of the left coronary artery. The results showed that treatment with SMND-309 via tail vein at doses of 10 and 20 mg/kg significantly prevented the elevation in ST segment level and the increase in serum creatine kinase-MB, lactate dehydrogenase, alanine aminotransferase and cardiac troponin T content. Meanwhile, SMND-309 significantly increased the activities of superoxide dismutase, catalase and glutathione peroxidase, decreased the content of malondialdehyde in myocardium, and reduced the myocardium necrosis scores and the number of apoptosis cardiocytes in accordance with the up-regulated expression of anti-apoptotic protein, Bcl-2 and the down-regulated expression of proapoptotic protein, Bax. Moreover, SMND-309 exhibits significantly higher potency compared to salvianolic acid B at the same mg/kg but not the same mol/kg. These findings indicate that SMND-309 has a protective potential against myocardial infarction injury and the protective effects may be due to its scavenging lipid peroxidation products, increasing endogenous antioxidant defence enzymes and attenuating cardiocyte apoptosis.

[The volatile components of three radix et rhizoma asari].

OBJECTIVE: To analyze and compare the volatile components of Asarum sieboldii Miq, Asarum himalaicum Hook. F. et Thoms and Asarum. debile Franch in the same area. METHODS: The volatile components were extracted from three Radix et Rhizoma Asari by solid-phrase microextraction and their contents were analyzed by gas chromatography-mass spectrometry (GC-MS). RESULTS: 59, 99 and 85 volatile components were identified from Asarum sieboldii Miq, Asarum himalaicum Hook. F. et Thoms and Asarum debile Franch, representing the ralative content of 82.75% - 99.43% of the volatile oil. 16 of same components were identified in the three Radix et Rhizoma Asari, and the contents of the same components were different among them. In addition, some unique components were identified in them respectively. CONCLUSION: There were differences among the chemical components and the contents of the volatile oil of the three Radix et Rhizoma Asari. The results could give certain reference value for the medicine whether Asarum himalaicum Hook. F. et Thoms and Asarum debile Franch can replace Asarum sieboldii Miq.

The total flavones from Semen cuscutae reverse the reduction of testosterone level and the expression of androgen receptor gene in kidney-yang deficient mice.

OBJECTIVE: To discover the effect of the total flavones from Semen cuscutae (TFSC) on the kidney-yang deficiency male mouse, especially on hormone levels and the androgen receptor (AR) mRNA and protein level in the kidney and testicle. METHODS: ICR male mouse were separated into six groups, and, except for the normal group, hydrocortisone was injected intraperitoneally to make the kidney-yang deficiency. The groups were then treated with TFSC, methyltestosterone and Jinkui Shenqi Wan, except for the normal group and control group. 14 days after administering, testosterone levels in the total serum were analysed by radioimmunoassay, AR mRNA levels measured by real time RT-PCR and protein levels by immunohistochemistry. RESULTS: The control group had the lowest testosterone level, AR mRNA level and protein level, and the TFSC can reverse the reduction of testosterone level, AR mRNA level and protein level induced by the hydrocortisone. CONCLUSIONS: This is the first study to demonstrate that TFSC treatment may reverse kidney-yang deficiency symptoms by restoring the levels of testosterone and AR mRNA and protein expression in the kidney and testicle.

[Changes of cortex mitochondrial function in chronic traumatic brain injury rats].

This experimental study was aimed to evaluate the injurious effects of chronic traumatic brain injury on cortex mitochondrial function in rats. The head of rat was impacted by a metal sphere in a weight-drop device twice per day for 30 days, cortex mitochondria were isolated. Then the mitochondria membrane fluidity, swelling, respiratory function, the activities of mitochondria respiratory enzymes and superoxide dismutase (SOD), the levels of phospholipid, malondial dehyde (MDA) and Ca2+ were determined to analyze the function of mitochondria. The data indicated that chronic closed traumatic brain injury caused severe neuronal mitochondrial injuries. The swelling of mitochondria was aggravated, the decomposability of mitochondrial membrane phospholipid was increased, the membrane fluidity of mitochondria was decreased; the chronic closed traumatic brain injury also significantly depressed the activities of respiratory enzymes and SOD of mitochondria, increased the level of MDA and Ca2+. The chronic closed traumatic brain injury induced damage to rat cortex mitochondria. The mechanisms may be derived from the secondary increase of free radicals induced by mitochondrial membrane injury and the obstacle of rat brain energy metabolism.

Cardiac muscle sarcolemma chromatographic stationary phase and its potential application in drug screening.

A new bioactive packing material for liquid chromatography, sarcolemma chromatography stationary phase (SCSP), is presented. Its surface characteristics are investigated, and it is found that the acceptors embedded in sarcolemma remained bioactive for more than a week. The retention behavior of antagonists and activators related to cardiac muscle sarcolemma on the SCSP chromatographic column shows the screening function of the SCSP column, and the retention behavior of the active components in the aether extract from the Chinese herb Ligusticum chuanxiong Hort. on the SCSP column reveals, to a certain extent, the separation function of the SCSP column. These suggest that SCSP is a potentially useful material in drug screening.

[Effect of phillyrin on the anti-obesity in nutritive obesity mice].

OBJECTIVE: To study on the anti-obesity effect of phillyrin in nutritive obesity mice. METHOD: The alimentary obesity model was established by hyperalimentation. The wet weight of fat, fat index, number of fat cells per unit visual field, Lee's index, jejunum microvillus area, serum triglyceride and cholesterol were selected to observe the anti-obesity effect of phillyrin. RESULT: Phillyrin could lower wet weight of fat (P < 0.01), fat index (P < 0.05 or P < 0.01), diameter of fat cell and Lee's index (P < 0.05), decrease the jejunum microvillus area, lower the level of serum triglyceride and cholesterol. CONCLUSION: Phillyrin has anti-obesity effect in nutritive obesity mice.

[Study on the interactions between Ligusticum chuanxiong extract and cardiac muscle membrane receptors by CMSP chromatography].

OBJECTIVE: To study the interactions between Ligusticum chuanxiong Hort extract and cardiac muscle membrane receptors. METHOD: The cell membrane of rabbit cardiac muscle was fixed on silicon to make cell membrane stationary phase (CMSP), and then the interactions were studied by comparing the retention characteristics of the extracts from different solvents with those of the antagonists or activators corresponding to known receptors in cardiac muscle membrane, and by competition effect on the retention characteristics of extracts when adding the antagonists or activators into the mobile phase. RESULT: Water extract and ethanol extract both had retentions on CMSP; the retention characteristics of water extract could be affected when water extract was in competition with the antagonists for alpha receptor, and could not be affected when with the activator beta1 receptor. CONCLUSION: It is possible that some components in water extract may combine with alpha receptor and no component with beta1 receptor, and that some components in ethanol extract may combine with cardiac muscle cell membrane. The process between active components and receptors in vivo can be imitated through the interactions between drugs and CMSP. The method provides references for the resolution of two applications: to screen the active components from Chinese medicine, and to figure out the type of receptors involved.

Neuroprotective effect of 20(S)-ginsenoside Rg3 on cerebral ischemia in rats.

This study was conducted to investigate the neuroprotective effects of 20(S)-ginsenoside Rg3 on focal cerebral ischemia in rats. Middle cerebral artery occlusion (MCAO) model in male Wistar-Kyoto (WKY) rats was employed. The behavioral tests were used to evaluate the damage to central nervous system. The infarct area of brain was assessed in the brain slices stained with 2,3,5-triphenyltetrazolium chloride (TTC). Hydrogen clearance techniques were used to monitor regional cerebral blood flow (rCBF), spectrophotometric assay methods were used to determine the activities of superoxide dismutase (SOD) and glutathione-peroxidase (GSH-Px), contents of malondialdehyde (MDA) and adenosine triphosphate (ATP) of the brain. Furthermore, the respiratory control ratio (RCR=State 3/State 4) was assessed in the brain mitochondria. The results showed that sublingual vein injection of 20(S)-ginsenoside Rg3 at doses of 10 and 5 mg kg(-1), but not 2.5 mg kg(-1) exhibited significant neuroprotective effects on rats against focal cerebral ischemic injury by markedly decreasing neurological deficit scores, reducing the infarct area and enhancing the rCBF compared with the control group. At the same time, 20(S)-ginsenoside Rg3 significantly improved mitochondrial energy metabolism, antagonized decreases in SOD and GSH-Px activities and increase in MDA level induced by cerebral ischemia. All these findings suggest that 20(S)-ginsenoside Rg3 might provide neuroprotection against the cerebral ischemia-induced injury in rat brain through reducing lipid peroxides, scavenging free radicals and improving the energy metabolism.

[Effects of Pedicularis decora extract on anti-oxidation injury in mice].

OBJECTIVE: To study the protection effects of Pedicalaris decorm extract on oxidation lesion in mice and the effective components of Pedicalaris decorm. METHODS: The total extract, BuOH soluble components and water soluble components of Pedicalaris decorm were administered (ig) 15 g.kg-1.d-1 to mice, and the oxidation injury model in mice was induced by i.p. alloxan 180 mg.kg-1. SOD, GSH-Px and LPO in red blood cell and liver, ALT, AST, AKP and r-globulin in serum, LPO and MAO.B in brain, liver index and spleen index were measured. RESULTS: All the three Pedicalaris decorm extracts can obviously lower abnormal contents of SOD, GSH-Px, LPO, ALT, AST, AKP, MAO.B and r-globulin induced by alloxa, and obviously improve abnormal decrease of liver index and spleen index. CONCLUSION: Pedicalaris decorm extract can inhibit oxidation lesion in mice. The effects of total extract and BuOH soluble components were better than water soluble components.